From ca9c1aaec4187fc9922cfb6b283fffef89286943 Mon Sep 17 00:00:00 2001 From: Ian Molton Date: Tue, 6 Jan 2009 20:11:51 +0000 Subject: ASoC: dapm: Allow explictly named mixer controls This patch allows you to define the mixer paths as having the same name as the paths they represent. This is required to support codecs such as the wm9705 neatly without extra controls in the alsa mixer. Signed-off-by: Ian Molton --- Documentation/sound/alsa/soc/dapm.txt | 3 +++ 1 file changed, 3 insertions(+) (limited to 'Documentation') diff --git a/Documentation/sound/alsa/soc/dapm.txt b/Documentation/sound/alsa/soc/dapm.txt index 46f9684d0b2..9e6763264a2 100644 --- a/Documentation/sound/alsa/soc/dapm.txt +++ b/Documentation/sound/alsa/soc/dapm.txt @@ -116,6 +116,9 @@ SOC_DAPM_SINGLE("HiFi Playback Switch", WM8731_APANA, 4, 1, 0), SND_SOC_DAPM_MIXER("Output Mixer", WM8731_PWR, 4, 1, wm8731_output_mixer_controls, ARRAY_SIZE(wm8731_output_mixer_controls)), +If you dont want the mixer elements prefixed with the name of the mixer widget, +you can use SND_SOC_DAPM_MIXER_NAMED_CTL instead. the parameters are the same +as for SND_SOC_DAPM_MIXER. 2.3 Platform/Machine domain Widgets ----------------------------------- -- cgit v1.2.3 From fbd59a8d1f7cf325fdb6828659f1fb76631e87b3 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Sat, 10 Jan 2009 21:58:08 -0800 Subject: cpumask: Use topology_core_cpumask()/topology_thread_cpumask() Impact: reduce stack usage, use new cpumask API. This actually uses topology_core_cpumask() and topology_thread_cpumask(), removing the only users of topology_core_siblings() and topology_thread_siblings() Signed-off-by: Rusty Russell Signed-off-by: Mike Travis Cc: linux-net-drivers@solarflare.com --- Documentation/cputopology.txt | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'Documentation') diff --git a/Documentation/cputopology.txt b/Documentation/cputopology.txt index 45932ec21ce..b41f3e58aef 100644 --- a/Documentation/cputopology.txt +++ b/Documentation/cputopology.txt @@ -18,11 +18,11 @@ For an architecture to support this feature, it must define some of these macros in include/asm-XXX/topology.h: #define topology_physical_package_id(cpu) #define topology_core_id(cpu) -#define topology_thread_siblings(cpu) -#define topology_core_siblings(cpu) +#define topology_thread_cpumask(cpu) +#define topology_core_cpumask(cpu) The type of **_id is int. -The type of siblings is cpumask_t. +The type of siblings is (const) struct cpumask *. To be consistent on all architectures, include/linux/topology.h provides default definitions for any of the above macros that are -- cgit v1.2.3 From d453379bc5d34d7f55b55931245de5ac1896fd8d Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Sun, 28 Dec 2008 16:45:34 +0100 Subject: ALSA: Update description of snd_card_create() in documents Signed-off-by: Takashi Iwai --- .../sound/alsa/DocBook/writing-an-alsa-driver.tmpl | 44 ++++++++++++---------- 1 file changed, 25 insertions(+), 19 deletions(-) (limited to 'Documentation') diff --git a/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl b/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl index 87a7c07ab65..320384c1791 100644 --- a/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl +++ b/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl @@ -492,9 +492,9 @@ } /* (2) */ - card = snd_card_new(index[dev], id[dev], THIS_MODULE, 0); - if (card == NULL) - return -ENOMEM; + err = snd_card_create(index[dev], id[dev], THIS_MODULE, 0, &card); + if (err < 0) + return err; /* (3) */ err = snd_mychip_create(card, pci, &chip); @@ -590,8 +590,9 @@ @@ -809,26 +810,28 @@ As mentioned above, to create a card instance, call - snd_card_new(). + snd_card_create(). - The function takes four arguments, the card-index number, the + The function takes five arguments, the card-index number, the id string, the module pointer (usually THIS_MODULE), - and the size of extra-data space. The last argument is used to + the size of extra-data space, and the pointer to return the + card instance. The extra_size argument is used to allocate card->private_data for the chip-specific data. Note that these data - are allocated by snd_card_new(). + are allocated by snd_card_create(). @@ -915,15 +918,16 @@
- 1. Allocating via <function>snd_card_new()</function>. + 1. Allocating via <function>snd_card_create()</function>. As mentioned above, you can pass the extra-data-length - to the 4th argument of snd_card_new(), i.e. + to the 4th argument of snd_card_create(), i.e. @@ -952,8 +956,8 @@ After allocating a card instance via - snd_card_new() (with - NULL on the 4th arg), call + snd_card_create() (with + 0 on the 4th arg), call kzalloc(). @@ -961,7 +965,7 @@ @@ -5750,8 +5754,9 @@ struct _snd_pcm_runtime { .... struct snd_card *card; struct mychip *chip; + int err; .... - card = snd_card_new(index[dev], id[dev], THIS_MODULE, NULL); + err = snd_card_create(index[dev], id[dev], THIS_MODULE, 0, &card); .... chip = kzalloc(sizeof(*chip), GFP_KERNEL); .... @@ -5763,7 +5768,7 @@ struct _snd_pcm_runtime { When you created the chip data with - snd_card_new(), it's anyway accessible + snd_card_create(), it's anyway accessible via private_data field. @@ -5775,9 +5780,10 @@ struct _snd_pcm_runtime { .... struct snd_card *card; struct mychip *chip; + int err; .... - card = snd_card_new(index[dev], id[dev], THIS_MODULE, - sizeof(struct mychip)); + err = snd_card_create(index[dev], id[dev], THIS_MODULE, + sizeof(struct mychip), &card); .... chip = card->private_data; .... -- cgit v1.2.3 From ee287587dafd77fd211e50637561224605c214b4 Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Wed, 14 Jan 2009 16:07:38 -0800 Subject: bzip2/lzma: update boot protocol specification Impact: documentation Update the boot protocol specification to include the currently supported file formats and their magic numbers. Signed-off-by: H. Peter Anvin --- Documentation/x86/boot.txt | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/x86/boot.txt b/Documentation/x86/boot.txt index fcdc62b3c3d..9ac70ffe2b7 100644 --- a/Documentation/x86/boot.txt +++ b/Documentation/x86/boot.txt @@ -542,7 +542,10 @@ Protocol: 2.08+ The payload may be compressed. The format of both the compressed and uncompressed data should be determined using the standard magic - numbers. Currently only gzip compressed ELF is used. + numbers. The currently supported compression formats are gzip + (magic numbers 1F 8B or 1F 9E), bzip2 (magic number 42 5A) and LZMA + (magic number 5D 00). The uncompressed payload is currently always ELF + (magic number 7F 45 4C 46). Field name: payload_length Type: read -- cgit v1.2.3 From e56d0cfe7790fd3218ae4f6aae1335547fea8763 Mon Sep 17 00:00:00 2001 From: Baodong Chen Date: Thu, 8 Jan 2009 19:24:29 +0800 Subject: Documentation/x86/boot.txt: modify fieldname Modify field names to the right ones: - start_sys was changed to start_sys_seg - iinitrd_addr_max was changed to ramdisk_max - pad2 was changed to pad2 and pad3 - readmode_swtch was changed to realmode_swtch Signed-off-by: Baodong Chen <[email]chenbdchenbd@gmail.com[email]> Acked-by: Jiri Kosina Signed-off-by: Ingo Molnar --- Documentation/x86/boot.txt | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) (limited to 'Documentation') diff --git a/Documentation/x86/boot.txt b/Documentation/x86/boot.txt index 7b4596ac412..12299697b7c 100644 --- a/Documentation/x86/boot.txt +++ b/Documentation/x86/boot.txt @@ -158,7 +158,7 @@ Offset Proto Name Meaning 0202/4 2.00+ header Magic signature "HdrS" 0206/2 2.00+ version Boot protocol version supported 0208/4 2.00+ realmode_swtch Boot loader hook (see below) -020C/2 2.00+ start_sys The load-low segment (0x1000) (obsolete) +020C/2 2.00+ start_sys_seg The load-low segment (0x1000) (obsolete) 020E/2 2.00+ kernel_version Pointer to kernel version string 0210/1 2.00+ type_of_loader Boot loader identifier 0211/1 2.00+ loadflags Boot protocol option flags @@ -170,10 +170,11 @@ Offset Proto Name Meaning 0224/2 2.01+ heap_end_ptr Free memory after setup end 0226/2 N/A pad1 Unused 0228/4 2.02+ cmd_line_ptr 32-bit pointer to the kernel command line -022C/4 2.03+ initrd_addr_max Highest legal initrd address +022C/4 2.03+ ramdisk_max Highest legal initrd address 0230/4 2.05+ kernel_alignment Physical addr alignment required for kernel 0234/1 2.05+ relocatable_kernel Whether kernel is relocatable or not -0235/3 N/A pad2 Unused +0235/1 N/A pad2 Unused +0236/2 N/A pad3 Unused 0238/4 2.06+ cmdline_size Maximum size of the kernel command line 023C/4 2.07+ hardware_subarch Hardware subarchitecture 0240/8 2.07+ hardware_subarch_data Subarchitecture-specific data @@ -299,14 +300,14 @@ Protocol: 2.00+ e.g. 0x0204 for version 2.04, and 0x0a11 for a hypothetical version 10.17. -Field name: readmode_swtch +Field name: realmode_swtch Type: modify (optional) Offset/size: 0x208/4 Protocol: 2.00+ Boot loader hook (see ADVANCED BOOT LOADER HOOKS below.) -Field name: start_sys +Field name: start_sys_seg Type: read Offset/size: 0x20c/2 Protocol: 2.00+ @@ -468,7 +469,7 @@ Protocol: 2.02+ zero, the kernel will assume that your boot loader does not support the 2.02+ protocol. -Field name: initrd_addr_max +Field name: ramdisk_max Type: read Offset/size: 0x22c/4 Protocol: 2.03+ -- cgit v1.2.3 From 08989930f91e4802b94e03eb54e5385bac112811 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Wed, 21 Jan 2009 07:43:23 +0100 Subject: ALSA: hda - Remove old models for STAC9872 from the document Signed-off-by: Takashi Iwai --- Documentation/sound/alsa/HD-Audio-Models.txt | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'Documentation') diff --git a/Documentation/sound/alsa/HD-Audio-Models.txt b/Documentation/sound/alsa/HD-Audio-Models.txt index 64eb1100eec..75914bcdce7 100644 --- a/Documentation/sound/alsa/HD-Audio-Models.txt +++ b/Documentation/sound/alsa/HD-Audio-Models.txt @@ -352,5 +352,4 @@ STAC92HD83* STAC9872 ======== - vaio Setup for VAIO FE550G/SZ110 - vaio-ar Setup for VAIO AR + N/A -- cgit v1.2.3 From 792b48780e8b6435d017cef4b5c304876a48653e Mon Sep 17 00:00:00 2001 From: Gerrit Renker Date: Fri, 16 Jan 2009 23:36:31 +0000 Subject: dccp: Implement both feature-local and feature-remote Sequence Window feature This adds full support for local/remote Sequence Window feature, from which the * sequence-number-validity (W) and * acknowledgment-number-validity (W') windows derive as specified in RFC 4340, 7.5.3. Specifically, the following is contained in this patch: * integrated new socket fields into dccp_sk; * updated the update_gsr/gss routines with regard to these fields; * updated handler code: the Sequence Window feature is located at the TX side, so the local feature is meant if the handler-rx flag is false; * the initialisation of `rcv_wnd' in reqsk is removed, since - rcv_wnd is not used by the code anywhere; - sequence number checks are not done in the LISTEN state (cf. 7.5.3); - dccp_check_req checks the Ack number validity more rigorously; * the `struct dccp_minisock' became empty and is now removed. Signed-off-by: Gerrit Renker Acked-by: Ian McDonald Signed-off-by: David S. Miller --- Documentation/networking/dccp.txt | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/networking/dccp.txt b/Documentation/networking/dccp.txt index 7a3bb1abb83..b132e4a3cf0 100644 --- a/Documentation/networking/dccp.txt +++ b/Documentation/networking/dccp.txt @@ -141,7 +141,8 @@ rx_ccid = 2 Default CCID for the receiver-sender half-connection; see tx_ccid. seq_window = 100 - The initial sequence window (sec. 7.5.2). + The initial sequence window (sec. 7.5.2) of the sender. This influences + the local ackno validity and the remote seqno validity windows (7.5.1). tx_qlen = 5 The size of the transmit buffer in packets. A value of 0 corresponds -- cgit v1.2.3 From d9a4268ee92ba1a2355c892a3add1fa66856b510 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Thu, 22 Jan 2009 17:40:18 +0100 Subject: ALSA: hda - Add quirk for Gateway %1616 laptop Gateway T1616 laptop needs EAPD always on while the current STAC9205 code turns off per HP plug. Added a new model "eapd" to keep it on. Reference: Novell bnc#467597 https://bugzilla.novell.com/show_bug.cgi?id=467597 Signed-off-by: Takashi Iwai --- Documentation/sound/alsa/HD-Audio-Models.txt | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/sound/alsa/HD-Audio-Models.txt b/Documentation/sound/alsa/HD-Audio-Models.txt index 75914bcdce7..ef6b22e2541 100644 --- a/Documentation/sound/alsa/HD-Audio-Models.txt +++ b/Documentation/sound/alsa/HD-Audio-Models.txt @@ -285,6 +285,7 @@ STAC9205/9254 dell-m42 Dell (unknown) dell-m43 Dell Precision dell-m44 Dell Inspiron + eapd Keep EAPD on (e.g. Gateway T1616) STAC9220/9221 ============= -- cgit v1.2.3 From c96330b083ce88b9fea428df99b4631f1b6410ef Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Wed, 28 Jan 2009 08:23:03 +0100 Subject: ALSA: Add description of new snd-msnd-* drivers Signed-off-by: Takashi Iwai --- Documentation/sound/alsa/ALSA-Configuration.txt | 48 +++++++++++++++++++++++++ 1 file changed, 48 insertions(+) (limited to 'Documentation') diff --git a/Documentation/sound/alsa/ALSA-Configuration.txt b/Documentation/sound/alsa/ALSA-Configuration.txt index 841a9365d5f..ba7b14a13ab 100644 --- a/Documentation/sound/alsa/ALSA-Configuration.txt +++ b/Documentation/sound/alsa/ALSA-Configuration.txt @@ -1185,6 +1185,54 @@ Prior to version 0.9.0rc4 options had a 'snd_' prefix. This was removed. This module supports multiple devices and PnP. + Module snd-msnd-classic + ----------------------- + + Module for Turtle Beach MultiSound Classic, Tahiti or Monterey + soundcards. + + io - Port # for msnd-classic card + irq - IRQ # for msnd-classic card + mem - Memory address (0xb0000, 0xc8000, 0xd0000, 0xd8000, + 0xe0000 or 0xe8000) + write_ndelay - enable write ndelay (default = 1) + calibrate_signal - calibrate signal (default = 0) + isapnp - ISA PnP detection - 0 = disable, 1 = enable (default) + digital - Digital daughterboard present (default = 0) + cfg - Config port (0x250, 0x260 or 0x270) default = PnP + reset - Reset all devices + mpu_io - MPU401 I/O port + mpu_irq - MPU401 irq# + ide_io0 - IDE port #0 + ide_io1 - IDE port #1 + ide_irq - IDE irq# + joystick_io - Joystick I/O port + + The driver requires firmware files "turtlebeach/msndinit.bin" and + "turtlebeach/msndperm.bin" in the proper firmware directory. + + See Documentation/sound/oss/MultiSound for important information + about this driver. Note that it has been discontinued, but the + Voyetra Turtle Beach knowledge base entry for it is still available + at + http://www.turtlebeach.com/site/kb_ftp/790.asp + + Module snd-msnd-pinnacle + ------------------------ + + Module for Turtle Beach MultiSound Pinnacle/Fiji soundcards. + + io - Port # for pinnacle/fiji card + irq - IRQ # for pinnalce/fiji card + mem - Memory address (0xb0000, 0xc8000, 0xd0000, 0xd8000, + 0xe0000 or 0xe8000) + write_ndelay - enable write ndelay (default = 1) + calibrate_signal - calibrate signal (default = 0) + isapnp - ISA PnP detection - 0 = disable, 1 = enable (default) + + The driver requires firmware files "turtlebeach/pndspini.bin" and + "turtlebeach/pndsperm.bin" in the proper firmware directory. + Module snd-mtpav ---------------- -- cgit v1.2.3 From b4f7ec46b6c151d31c068e46278efef7e43b5043 Mon Sep 17 00:00:00 2001 From: Peter Korsgaard Date: Wed, 14 Jan 2009 15:52:41 +0100 Subject: powerpc: convert dts-bindings/fsl/dma.txt to dts-v1 syntax Signed-off-by: Peter Korsgaard Signed-off-by: Kumar Gala --- Documentation/powerpc/dts-bindings/fsl/dma.txt | 34 +++++++++++++------------- 1 file changed, 17 insertions(+), 17 deletions(-) (limited to 'Documentation') diff --git a/Documentation/powerpc/dts-bindings/fsl/dma.txt b/Documentation/powerpc/dts-bindings/fsl/dma.txt index cc453110fc4..0732cdd05ba 100644 --- a/Documentation/powerpc/dts-bindings/fsl/dma.txt +++ b/Documentation/powerpc/dts-bindings/fsl/dma.txt @@ -35,30 +35,30 @@ Example: #address-cells = <1>; #size-cells = <1>; compatible = "fsl,mpc8349-dma", "fsl,elo-dma"; - reg = <82a8 4>; - ranges = <0 8100 1a4>; + reg = <0x82a8 4>; + ranges = <0 0x8100 0x1a4>; interrupt-parent = <&ipic>; - interrupts = <47 8>; + interrupts = <71 8>; cell-index = <0>; dma-channel@0 { compatible = "fsl,mpc8349-dma-channel", "fsl,elo-dma-channel"; cell-index = <0>; - reg = <0 80>; + reg = <0 0x80>; }; dma-channel@80 { compatible = "fsl,mpc8349-dma-channel", "fsl,elo-dma-channel"; cell-index = <1>; - reg = <80 80>; + reg = <0x80 0x80>; }; dma-channel@100 { compatible = "fsl,mpc8349-dma-channel", "fsl,elo-dma-channel"; cell-index = <2>; - reg = <100 80>; + reg = <0x100 0x80>; }; dma-channel@180 { compatible = "fsl,mpc8349-dma-channel", "fsl,elo-dma-channel"; cell-index = <3>; - reg = <180 80>; + reg = <0x180 0x80>; }; }; @@ -93,36 +93,36 @@ Example: #address-cells = <1>; #size-cells = <1>; compatible = "fsl,mpc8540-dma", "fsl,eloplus-dma"; - reg = <21300 4>; - ranges = <0 21100 200>; + reg = <0x21300 4>; + ranges = <0 0x21100 0x200>; cell-index = <0>; dma-channel@0 { compatible = "fsl,mpc8540-dma-channel", "fsl,eloplus-dma-channel"; - reg = <0 80>; + reg = <0 0x80>; cell-index = <0>; interrupt-parent = <&mpic>; - interrupts = <14 2>; + interrupts = <20 2>; }; dma-channel@80 { compatible = "fsl,mpc8540-dma-channel", "fsl,eloplus-dma-channel"; - reg = <80 80>; + reg = <0x80 0x80>; cell-index = <1>; interrupt-parent = <&mpic>; - interrupts = <15 2>; + interrupts = <21 2>; }; dma-channel@100 { compatible = "fsl,mpc8540-dma-channel", "fsl,eloplus-dma-channel"; - reg = <100 80>; + reg = <0x100 0x80>; cell-index = <2>; interrupt-parent = <&mpic>; - interrupts = <16 2>; + interrupts = <22 2>; }; dma-channel@180 { compatible = "fsl,mpc8540-dma-channel", "fsl,eloplus-dma-channel"; - reg = <180 80>; + reg = <0x180 0x80>; cell-index = <3>; interrupt-parent = <&mpic>; - interrupts = <17 2>; + interrupts = <23 2>; }; }; -- cgit v1.2.3 From 9e128fddcc589db4e7d9e8328f656ae4a21a2808 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Thu, 29 Jan 2009 11:49:10 +0100 Subject: ALSA: Add missing description of snd-cmi8330 module parameters Signed-off-by: Takashi Iwai --- Documentation/sound/alsa/ALSA-Configuration.txt | 3 +++ 1 file changed, 3 insertions(+) (limited to 'Documentation') diff --git a/Documentation/sound/alsa/ALSA-Configuration.txt b/Documentation/sound/alsa/ALSA-Configuration.txt index 841a9365d5f..7134a8f7044 100644 --- a/Documentation/sound/alsa/ALSA-Configuration.txt +++ b/Documentation/sound/alsa/ALSA-Configuration.txt @@ -346,6 +346,9 @@ Prior to version 0.9.0rc4 options had a 'snd_' prefix. This was removed. sbirq - IRQ # for CMI8330 chip (SB16) sbdma8 - 8bit DMA # for CMI8330 chip (SB16) sbdma16 - 16bit DMA # for CMI8330 chip (SB16) + fmport - (optional) OPL3 I/O port + mpuport - (optional) MPU401 I/O port + mpuirq - (optional) MPU401 irq # This module supports multiple cards and autoprobe. -- cgit v1.2.3 From c557289cb8ea063bd09db88f8a687a841556e291 Mon Sep 17 00:00:00 2001 From: Michael Buesch Date: Sat, 27 Dec 2008 18:26:39 +0100 Subject: b43: Change schedule for old-fw support removal The scheduled date for the removal of old fw support was in July 2008. However, we're not going to remove the support unless it causes a major headache. So change the schedule from "July 2008" to "when it causes headaches". Signed-off-by: Michael Buesch Signed-off-by: John W. Linville --- Documentation/feature-removal-schedule.txt | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 5ddbe350487..ac98851f7a0 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -229,7 +229,9 @@ Who: Jan Engelhardt --------------------------- What: b43 support for firmware revision < 410 -When: July 2008 +When: The schedule was July 2008, but it was decided that we are going to keep the + code as long as there are no major maintanance headaches. + So it _could_ be removed _any_ time now, if it conflicts with something new. Why: The support code for the old firmware hurts code readability/maintainability and slightly hurts runtime performance. Bugfixes for the old firmware are not provided by Broadcom anymore. -- cgit v1.2.3 From d1c3a37ceeb1a5ea02991a0476355f1a1d3b3e83 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Wed, 7 Jan 2009 00:26:10 +0100 Subject: mac80211: clarify alignment docs, fix up alignment Not all drivers are capable of passing properly aligned frames, in particular with mesh networking no hardware will support completely aligning it correctly. This patch adds code to align the data payload to a 4-byte boundary in memory for those platforms that require this, or when CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT is set. Signed-off-by: Johannes Berg Signed-off-by: John W. Linville --- Documentation/DocBook/mac80211.tmpl | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'Documentation') diff --git a/Documentation/DocBook/mac80211.tmpl b/Documentation/DocBook/mac80211.tmpl index 77c3c202991..bdf908a6e54 100644 --- a/Documentation/DocBook/mac80211.tmpl +++ b/Documentation/DocBook/mac80211.tmpl @@ -165,8 +165,8 @@ usage should require reading the full document. !Pinclude/net/mac80211.h Frame format - Alignment issues - TBD + Packet alignment +!Pnet/mac80211/rx.c Packet alignment Calling into mac80211 from interrupts -- cgit v1.2.3 From 4be8c3873e0b88397866d3ede578503e188f9ad2 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Wed, 7 Jan 2009 18:28:20 +0100 Subject: mac80211: extend/document powersave API This modifies hardware flags for powersave to support three different flags: * IEEE80211_HW_SUPPORTS_PS - indicates general PS support * IEEE80211_HW_PS_NULLFUNC_STACK - indicates nullfunc sending in software * IEEE80211_HW_SUPPORTS_DYNAMIC_PS - indicates dynamic PS on the device It also adds documentation for all this which explains how to set the various flags. Additionally, it fixes a few things: * a spot where && was used to test flags * enable CONF_PS only when associated again Signed-off-by: Johannes Berg Signed-off-by: John W. Linville --- Documentation/DocBook/mac80211.tmpl | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'Documentation') diff --git a/Documentation/DocBook/mac80211.tmpl b/Documentation/DocBook/mac80211.tmpl index bdf908a6e54..8af6d962687 100644 --- a/Documentation/DocBook/mac80211.tmpl +++ b/Documentation/DocBook/mac80211.tmpl @@ -17,8 +17,7 @@ - 2007 - 2008 + 2007-2009 Johannes Berg @@ -223,6 +222,11 @@ usage should require reading the full document. !Finclude/net/mac80211.h ieee80211_key_flags + + Powersave support +!Pinclude/net/mac80211.h Powersave support + + Multiple queues and QoS support TBD -- cgit v1.2.3 From 504a06d8b05cb5b214c9b97752d8451e88d9ef81 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Fri, 30 Jan 2009 19:59:10 +0100 Subject: ALSA: Add description of new fm_port option for snd-es1688 driver Signed-off-by: Takashi Iwai --- Documentation/sound/alsa/ALSA-Configuration.txt | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/sound/alsa/ALSA-Configuration.txt b/Documentation/sound/alsa/ALSA-Configuration.txt index 7134a8f7044..a763b76afe5 100644 --- a/Documentation/sound/alsa/ALSA-Configuration.txt +++ b/Documentation/sound/alsa/ALSA-Configuration.txt @@ -609,6 +609,7 @@ Prior to version 0.9.0rc4 options had a 'snd_' prefix. This was removed. Module for ESS AudioDrive ES-1688 and ES-688 sound cards. port - port # for ES-1688 chip (0x220,0x240,0x260) + fm_port - port # for OPL3 (option; share the same port as default) mpu_port - port # for MPU-401 port (0x300,0x310,0x320,0x330), -1 = disable (default) irq - IRQ # for ES-1688 chip (5,7,9,10) mpu_irq - IRQ # for MPU-401 port (5,7,9,10) -- cgit v1.2.3 From eefef1cf7653cd4e0aaf743c00ae8345086cdc01 Mon Sep 17 00:00:00 2001 From: Stephen Hemminger Date: Sun, 1 Feb 2009 01:04:33 -0800 Subject: net: add ARP notify option for devices This adds another inet device option to enable gratuitous ARP when device is brought up or address change. This is handy for clusters or virtualization. Signed-off-by: Stephen Hemminger Signed-off-by: Jeremy Fitzhardinge Signed-off-by: David S. Miller --- Documentation/networking/ip-sysctl.txt | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'Documentation') diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index c7712787933..ff3f219ee4d 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -782,6 +782,12 @@ arp_ignore - INTEGER The max value from conf/{all,interface}/arp_ignore is used when ARP request is received on the {interface} +arp_notify - BOOLEAN + Define mode for notification of address and device changes. + 0 - (default): do nothing + 1 - Generate gratuitous arp replies when device is brought up + or hardware address changes. + arp_accept - BOOLEAN Define behavior when gratuitous arp replies are received: 0 - drop gratuitous arp frames -- cgit v1.2.3 From 123848e77623b9996288e85433985439c157fcd0 Mon Sep 17 00:00:00 2001 From: Tony Vroon Date: Tue, 3 Feb 2009 11:13:34 +0000 Subject: ALSA: Document tyan model for Realtek ALC262 As just pointed out to me, the new tyan model for ALC262 was implemented but not documented. This adds the board to the list, using both its marketing name (Thunder n6650W) and its model number (S2915-E). Signed-off-by: Tony Vroon Signed-off-by: Takashi Iwai --- Documentation/sound/alsa/HD-Audio-Models.txt | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/sound/alsa/HD-Audio-Models.txt b/Documentation/sound/alsa/HD-Audio-Models.txt index c9df9db5835..8f40999a456 100644 --- a/Documentation/sound/alsa/HD-Audio-Models.txt +++ b/Documentation/sound/alsa/HD-Audio-Models.txt @@ -56,6 +56,7 @@ ALC262 sony-assamd Sony ASSAMD toshiba-s06 Toshiba S06 toshiba-rx1 Toshiba RX1 + tyan Tyan Thunder n6650W (S2915-E) ultra Samsung Q1 Ultra Vista model lenovo-3000 Lenovo 3000 y410 nec NEC Versa S9100 -- cgit v1.2.3 From 4d7902f22b0804730b80f7a4147f676430248a3a Mon Sep 17 00:00:00 2001 From: Andy Fleming Date: Wed, 4 Feb 2009 16:43:44 -0800 Subject: gianfar: Fix stashing support Stashing is only supported on the 85xx (e500-based) SoCs. The 83xx and 86xx chips don't have a proper cache for this. U-Boot has been updated to add stashing properties to the device tree nodes of gianfar devices on 85xx. So now we modify Linux to keep stashing off unless those properties are there. Signed-off-by: Andy Fleming Signed-off-by: David S. Miller --- Documentation/powerpc/dts-bindings/fsl/tsec.txt | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'Documentation') diff --git a/Documentation/powerpc/dts-bindings/fsl/tsec.txt b/Documentation/powerpc/dts-bindings/fsl/tsec.txt index 7fa4b27574b..edb7ae19e86 100644 --- a/Documentation/powerpc/dts-bindings/fsl/tsec.txt +++ b/Documentation/powerpc/dts-bindings/fsl/tsec.txt @@ -56,6 +56,12 @@ Properties: hardware. - fsl,magic-packet : If present, indicates that the hardware supports waking up via magic packet. + - bd-stash : If present, indicates that the hardware supports stashing + buffer descriptors in the L2. + - rx-stash-len : Denotes the number of bytes of a received buffer to stash + in the L2. + - rx-stash-idx : Denotes the index of the first byte from the received + buffer to stash in the L2. Example: ethernet@24000 { -- cgit v1.2.3 From 6146f0d5e47ca4047ffded0fb79b6c25359b386c Mon Sep 17 00:00:00 2001 From: Mimi Zohar Date: Wed, 4 Feb 2009 09:06:57 -0500 Subject: integrity: IMA hooks This patch replaces the generic integrity hooks, for which IMA registered itself, with IMA integrity hooks in the appropriate places directly in the fs directory. Signed-off-by: Mimi Zohar Acked-by: Serge Hallyn Signed-off-by: James Morris --- Documentation/kernel-parameters.txt | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index a2d8805c03d..7c67b94d182 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -44,6 +44,7 @@ parameter is applicable: FB The frame buffer device is enabled. HW Appropriate hardware is enabled. IA-64 IA-64 architecture is enabled. + IMA Integrity measurement architecture is enabled. IOSCHED More than one I/O scheduler is enabled. IP_PNP IP DHCP, BOOTP, or RARP is enabled. ISAPNP ISA PnP code is enabled. -- cgit v1.2.3 From 3323eec921efd815178a23107ab63588c605c0b2 Mon Sep 17 00:00:00 2001 From: Mimi Zohar Date: Wed, 4 Feb 2009 09:06:58 -0500 Subject: integrity: IMA as an integrity service provider IMA provides hardware (TPM) based measurement and attestation for file measurements. As the Trusted Computing (TPM) model requires, IMA measures all files before they are accessed in any way (on the integrity_bprm_check, integrity_path_check and integrity_file_mmap hooks), and commits the measurements to the TPM. Once added to the TPM, measurements can not be removed. In addition, IMA maintains a list of these file measurements, which can be used to validate the aggregate value stored in the TPM. The TPM can sign these measurements, and thus the system can prove, to itself and to a third party, the system's integrity in a way that cannot be circumvented by malicious or compromised software. - alloc ima_template_entry before calling ima_store_template() - log ima_add_boot_aggregate() failure - removed unused IMA_TEMPLATE_NAME_LEN - replaced hard coded string length with #define name Signed-off-by: Mimi Zohar Signed-off-by: James Morris --- Documentation/kernel-parameters.txt | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'Documentation') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 7c67b94d182..31e0c2c3c6e 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -895,6 +895,15 @@ and is between 256 and 4096 characters. It is defined in the file ihash_entries= [KNL] Set number of hash buckets for inode cache. + ima_audit= [IMA] + Format: { "0" | "1" } + 0 -- integrity auditing messages. (Default) + 1 -- enable informational integrity auditing messages. + + ima_hash= [IMA] + Formt: { "sha1" | "md5" } + default: "sha1" + in2000= [HW,SCSI] See header of drivers/scsi/in2000.c. -- cgit v1.2.3 From 4af4662fa4a9dc62289c580337ae2506339c4729 Mon Sep 17 00:00:00 2001 From: Mimi Zohar Date: Wed, 4 Feb 2009 09:07:00 -0500 Subject: integrity: IMA policy Support for a user loadable policy through securityfs with support for LSM specific policy data. - free invalid rule in ima_parse_add_rule() Signed-off-by: Mimi Zohar Acked-by: Serge Hallyn Signed-off-by: James Morris --- Documentation/ABI/testing/ima_policy | 61 ++++++++++++++++++++++++++++++++++++ 1 file changed, 61 insertions(+) create mode 100644 Documentation/ABI/testing/ima_policy (limited to 'Documentation') diff --git a/Documentation/ABI/testing/ima_policy b/Documentation/ABI/testing/ima_policy new file mode 100644 index 00000000000..6434f0df012 --- /dev/null +++ b/Documentation/ABI/testing/ima_policy @@ -0,0 +1,61 @@ +What: security/ima/policy +Date: May 2008 +Contact: Mimi Zohar +Description: + The Trusted Computing Group(TCG) runtime Integrity + Measurement Architecture(IMA) maintains a list of hash + values of executables and other sensitive system files + loaded into the run-time of this system. At runtime, + the policy can be constrained based on LSM specific data. + Policies are loaded into the securityfs file ima/policy + by opening the file, writing the rules one at a time and + then closing the file. The new policy takes effect after + the file ima/policy is closed. + + rule format: action [condition ...] + + action: measure | dont_measure + condition:= base | lsm + base: [[func=] [mask=] [fsmagic=] [uid=]] + lsm: [[subj_user=] [subj_role=] [subj_type=] + [obj_user=] [obj_role=] [obj_type=]] + + base: func:= [BPRM_CHECK][FILE_MMAP][INODE_PERMISSION] + mask:= [MAY_READ] [MAY_WRITE] [MAY_APPEND] [MAY_EXEC] + fsmagic:= hex value + uid:= decimal value + lsm: are LSM specific + + default policy: + # PROC_SUPER_MAGIC + dont_measure fsmagic=0x9fa0 + # SYSFS_MAGIC + dont_measure fsmagic=0x62656572 + # DEBUGFS_MAGIC + dont_measure fsmagic=0x64626720 + # TMPFS_MAGIC + dont_measure fsmagic=0x01021994 + # SECURITYFS_MAGIC + dont_measure fsmagic=0x73636673 + + measure func=BPRM_CHECK + measure func=FILE_MMAP mask=MAY_EXEC + measure func=INODE_PERM mask=MAY_READ uid=0 + + The default policy measures all executables in bprm_check, + all files mmapped executable in file_mmap, and all files + open for read by root in inode_permission. + + Examples of LSM specific definitions: + + SELinux: + # SELINUX_MAGIC + dont_measure fsmagic=0xF97CFF8C + + dont_measure obj_type=var_log_t + dont_measure obj_type=auditd_log_t + measure subj_user=system_u func=INODE_PERM mask=MAY_READ + measure subj_role=system_r func=INODE_PERM mask=MAY_READ + + Smack: + measure subj_user=_ func=INODE_PERM mask=MAY_READ -- cgit v1.2.3 From 34bcda616e5308a0633d5bfabcc090d7aa09b494 Mon Sep 17 00:00:00 2001 From: Anton Vorontsov Date: Thu, 5 Feb 2009 22:04:47 +0300 Subject: powerpc: Document FSL eSDHC bindings This patch documents OF bindings for the Freescale Enhanced Secure Digital Host Controller. Signed-off-by: Anton Vorontsov Signed-off-by: Kumar Gala --- Documentation/powerpc/dts-bindings/fsl/esdhc.txt | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) create mode 100644 Documentation/powerpc/dts-bindings/fsl/esdhc.txt (limited to 'Documentation') diff --git a/Documentation/powerpc/dts-bindings/fsl/esdhc.txt b/Documentation/powerpc/dts-bindings/fsl/esdhc.txt new file mode 100644 index 00000000000..60084655776 --- /dev/null +++ b/Documentation/powerpc/dts-bindings/fsl/esdhc.txt @@ -0,0 +1,24 @@ +* Freescale Enhanced Secure Digital Host Controller (eSDHC) + +The Enhanced Secure Digital Host Controller provides an interface +for MMC, SD, and SDIO types of memory cards. + +Required properties: + - compatible : should be + "fsl,-esdhc", "fsl,mpc8379-esdhc" for MPC83xx processors. + "fsl,-esdhc", "fsl,mpc8536-esdhc" for MPC85xx processors. + - reg : should contain eSDHC registers location and length. + - interrupts : should contain eSDHC interrupt. + - interrupt-parent : interrupt source phandle. + - clock-frequency : specifies eSDHC base clock frequency. + +Example: + +sdhci@2e000 { + compatible = "fsl,mpc8378-esdhc", "fsl,mpc8379-esdhc"; + reg = <0x2e000 0x1000>; + interrupts = <42 0x8>; + interrupt-parent = <&ipic>; + /* Filled in by U-Boot */ + clock-frequency = <0>; +}; -- cgit v1.2.3 From ae374d667a54fb5e2c9c0c4e87b206bd665f3ad6 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Fri, 13 Feb 2009 08:33:55 +0100 Subject: ALSA: hda - Update documentation Update documentation regarding codec probing; the new probe_only option and the new probe_mask usage. Signed-off-by: Takashi Iwai --- Documentation/sound/alsa/ALSA-Configuration.txt | 3 +++ Documentation/sound/alsa/HD-Audio.txt | 17 +++++++++++++++++ 2 files changed, 20 insertions(+) (limited to 'Documentation') diff --git a/Documentation/sound/alsa/ALSA-Configuration.txt b/Documentation/sound/alsa/ALSA-Configuration.txt index 841a9365d5f..012afd7afb1 100644 --- a/Documentation/sound/alsa/ALSA-Configuration.txt +++ b/Documentation/sound/alsa/ALSA-Configuration.txt @@ -757,6 +757,9 @@ Prior to version 0.9.0rc4 options had a 'snd_' prefix. This was removed. model - force the model name position_fix - Fix DMA pointer (0 = auto, 1 = use LPIB, 2 = POSBUF) probe_mask - Bitmask to probe codecs (default = -1, meaning all slots) + When the bit 8 (0x100) is set, the lower 8 bits are used + as the "fixed" codec slots; i.e. the driver probes the + slots regardless what hardware reports back probe_only - Only probing and no codec initialization (default=off); Useful to check the initial codec status for debugging bdl_pos_adj - Specifies the DMA IRQ timing delay in samples. diff --git a/Documentation/sound/alsa/HD-Audio.txt b/Documentation/sound/alsa/HD-Audio.txt index 8d68fff7183..99f7fbbe3e6 100644 --- a/Documentation/sound/alsa/HD-Audio.txt +++ b/Documentation/sound/alsa/HD-Audio.txt @@ -109,6 +109,13 @@ slot, pass `probe_mask=1`. For the first and the third slots, pass Since 2.6.29 kernel, the driver has a more robust probing method, so this error might happen rarely, though. +On a machine with a broken BIOS, sometimes you need to force the +driver to probe the codec slots the hardware doesn't report for use. +In such a case, turn the bit 8 (0x100) of `probe_mask` option on. +Then the rest 8 bits are passed as the codec slots to probe +unconditionally. For example, `probe_mask=0x103` will force to probe +the codec slots 0 and 1 no matter what the hardware reports. + Interrupt Handling ~~~~~~~~~~~~~~~~~~ @@ -461,6 +468,16 @@ run with `--no-upload` option, and attach the generated file. There are some other useful options. See `--help` option output for details. +When a probe error occurs or when the driver obviously assigns a +mismatched model, it'd be helpful to load the driver with +`probe_only=1` option (at best after the cold reboot) and run +alsa-info at this state. With this option, the driver won't configure +the mixer and PCM but just tries to probe the codec slot. After +probing, the proc file is available, so you can get the raw codec +information before modified by the driver. Of course, the driver +isn't usable with `probe_only=1`. But you can continue the +configuration via hwdep sysfs file if hda-reconfig option is enabled. + hda-verb ~~~~~~~~ -- cgit v1.2.3 From 27e089888fb1a3d1d13892262f9d522b03985044 Mon Sep 17 00:00:00 2001 From: Aristeu Sergio Rozanski Filho Date: Thu, 12 Feb 2009 17:50:37 -0500 Subject: ALSA: hda: add quirk for Lenovo X200 laptop dock Currently the HP connector on X200 dock doesn't detect when a HP is connected nor allows sound to be played using it. This patch fixes the problem by adding a quirk for this specific model. It's possible that others have the same NID (0x19) to report when dock HP is connected, but I don't have access to any. Please Cc me in the reply since I'm not subscribed to alsa-devel@. Signed-off-by: Aristeu Rozanski Signed-off-by: Takashi Iwai --- Documentation/sound/alsa/HD-Audio-Models.txt | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/sound/alsa/HD-Audio-Models.txt b/Documentation/sound/alsa/HD-Audio-Models.txt index 8f40999a456..0e52d273ce9 100644 --- a/Documentation/sound/alsa/HD-Audio-Models.txt +++ b/Documentation/sound/alsa/HD-Audio-Models.txt @@ -262,6 +262,7 @@ Conexant 5051 ============= laptop Basic Laptop config (default) hp HP Spartan laptop + lenovo-x200 Lenovo X200 laptop STAC9200 ======== -- cgit v1.2.3 From f510b233cfc7bfd57b6007071c52aa42e3d16b06 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Thu, 22 Jan 2009 17:53:47 +0100 Subject: lockdep: get_user_chars() redo Generic, states independent, get_user_chars(). Signed-off-by: Peter Zijlstra Signed-off-by: Ingo Molnar --- Documentation/lockdep-design.txt | 30 +++++++++++++++++------------- 1 file changed, 17 insertions(+), 13 deletions(-) (limited to 'Documentation') diff --git a/Documentation/lockdep-design.txt b/Documentation/lockdep-design.txt index 48877301815..938ea22f2cc 100644 --- a/Documentation/lockdep-design.txt +++ b/Documentation/lockdep-design.txt @@ -27,33 +27,37 @@ lock-class. State ----- -The validator tracks lock-class usage history into 5 separate state bits: +The validator tracks lock-class usage history into 4n + 1 separate state bits: -- 'ever held in hardirq context' [ == hardirq-safe ] -- 'ever held in softirq context' [ == softirq-safe ] -- 'ever held with hardirqs enabled' [ == hardirq-unsafe ] -- 'ever held with softirqs and hardirqs enabled' [ == softirq-unsafe ] +- 'ever held in STATE context' +- 'ever head as readlock in STATE context' +- 'ever head with STATE enabled' +- 'ever head as readlock with STATE enabled' + +Where STATE can be either one of (kernel/lockdep_states.h) + - hardirq + - softirq + - reclaim_fs - 'ever used' [ == !unused ] -When locking rules are violated, these 4 state bits are presented in the -locking error messages, inside curlies. A contrived example: +When locking rules are violated, these state bits are presented in the +locking error messages, inside curlies. A contrived example: modprobe/2287 is trying to acquire lock: - (&sio_locks[i].lock){--..}, at: [] mutex_lock+0x21/0x24 + (&sio_locks[i].lock){-.-...}, at: [] mutex_lock+0x21/0x24 but task is already holding lock: - (&sio_locks[i].lock){--..}, at: [] mutex_lock+0x21/0x24 + (&sio_locks[i].lock){-.-...}, at: [] mutex_lock+0x21/0x24 -The bit position indicates hardirq, softirq, hardirq-read, -softirq-read respectively, and the character displayed in each -indicates: +The bit position indicates STATE, STATE-read, for each of the states listed +above, and the character displayed in each indicates: '.' acquired while irqs disabled '+' acquired in irq context '-' acquired with irqs enabled - '?' read acquired in irq context with irqs enabled. + '?' acquired in irq context with irqs enabled. Unused mutexes cannot be part of the cause of an error. -- cgit v1.2.3 From cb9eff097831007afb30d64373f29d99825d0068 Mon Sep 17 00:00:00 2001 From: Patrick Ohly Date: Thu, 12 Feb 2009 05:03:36 +0000 Subject: net: new user space API for time stamping of incoming and outgoing packets User space can request hardware and/or software time stamping. Reporting of the result(s) via a new control message is enabled separately for each field in the message because some of the fields may require additional computation and thus cause overhead. User space can tell the different kinds of time stamps apart and choose what suits its needs. When a TX timestamp operation is requested, the TX skb will be cloned and the clone will be time stamped (in hardware or software) and added to the socket error queue of the skb, if the skb has a socket associated with it. The actual TX timestamp will reach userspace as a RX timestamp on the cloned packet. If timestamping is requested and no timestamping is done in the device driver (potentially this may use hardware timestamping), it will be done in software after the device's start_hard_xmit routine. Signed-off-by: Patrick Ohly Signed-off-by: David S. Miller --- Documentation/networking/timestamping.txt | 178 +++++++ Documentation/networking/timestamping/.gitignore | 1 + Documentation/networking/timestamping/Makefile | 6 + .../networking/timestamping/timestamping.c | 533 +++++++++++++++++++++ 4 files changed, 718 insertions(+) create mode 100644 Documentation/networking/timestamping.txt create mode 100644 Documentation/networking/timestamping/.gitignore create mode 100644 Documentation/networking/timestamping/Makefile create mode 100644 Documentation/networking/timestamping/timestamping.c (limited to 'Documentation') diff --git a/Documentation/networking/timestamping.txt b/Documentation/networking/timestamping.txt new file mode 100644 index 00000000000..a681a65b5bc --- /dev/null +++ b/Documentation/networking/timestamping.txt @@ -0,0 +1,178 @@ +The existing interfaces for getting network packages time stamped are: + +* SO_TIMESTAMP + Generate time stamp for each incoming packet using the (not necessarily + monotonous!) system time. Result is returned via recv_msg() in a + control message as timeval (usec resolution). + +* SO_TIMESTAMPNS + Same time stamping mechanism as SO_TIMESTAMP, but returns result as + timespec (nsec resolution). + +* IP_MULTICAST_LOOP + SO_TIMESTAMP[NS] + Only for multicasts: approximate send time stamp by receiving the looped + packet and using its receive time stamp. + +The following interface complements the existing ones: receive time +stamps can be generated and returned for arbitrary packets and much +closer to the point where the packet is really sent. Time stamps can +be generated in software (as before) or in hardware (if the hardware +has such a feature). + +SO_TIMESTAMPING: + +Instructs the socket layer which kind of information is wanted. The +parameter is an integer with some of the following bits set. Setting +other bits is an error and doesn't change the current state. + +SOF_TIMESTAMPING_TX_HARDWARE: try to obtain send time stamp in hardware +SOF_TIMESTAMPING_TX_SOFTWARE: if SOF_TIMESTAMPING_TX_HARDWARE is off or + fails, then do it in software +SOF_TIMESTAMPING_RX_HARDWARE: return the original, unmodified time stamp + as generated by the hardware +SOF_TIMESTAMPING_RX_SOFTWARE: if SOF_TIMESTAMPING_RX_HARDWARE is off or + fails, then do it in software +SOF_TIMESTAMPING_RAW_HARDWARE: return original raw hardware time stamp +SOF_TIMESTAMPING_SYS_HARDWARE: return hardware time stamp transformed to + the system time base +SOF_TIMESTAMPING_SOFTWARE: return system time stamp generated in + software + +SOF_TIMESTAMPING_TX/RX determine how time stamps are generated. +SOF_TIMESTAMPING_RAW/SYS determine how they are reported in the +following control message: + struct scm_timestamping { + struct timespec systime; + struct timespec hwtimetrans; + struct timespec hwtimeraw; + }; + +recvmsg() can be used to get this control message for regular incoming +packets. For send time stamps the outgoing packet is looped back to +the socket's error queue with the send time stamp(s) attached. It can +be received with recvmsg(flags=MSG_ERRQUEUE). The call returns the +original outgoing packet data including all headers preprended down to +and including the link layer, the scm_timestamping control message and +a sock_extended_err control message with ee_errno==ENOMSG and +ee_origin==SO_EE_ORIGIN_TIMESTAMPING. A socket with such a pending +bounced packet is ready for reading as far as select() is concerned. + +All three values correspond to the same event in time, but were +generated in different ways. Each of these values may be empty (= all +zero), in which case no such value was available. If the application +is not interested in some of these values, they can be left blank to +avoid the potential overhead of calculating them. + +systime is the value of the system time at that moment. This +corresponds to the value also returned via SO_TIMESTAMP[NS]. If the +time stamp was generated by hardware, then this field is +empty. Otherwise it is filled in if SOF_TIMESTAMPING_SOFTWARE is +set. + +hwtimeraw is the original hardware time stamp. Filled in if +SOF_TIMESTAMPING_RAW_HARDWARE is set. No assumptions about its +relation to system time should be made. + +hwtimetrans is the hardware time stamp transformed so that it +corresponds as good as possible to system time. This correlation is +not perfect; as a consequence, sorting packets received via different +NICs by their hwtimetrans may differ from the order in which they were +received. hwtimetrans may be non-monotonic even for the same NIC. +Filled in if SOF_TIMESTAMPING_SYS_HARDWARE is set. Requires support +by the network device and will be empty without that support. + + +SIOCSHWTSTAMP: + +Hardware time stamping must also be initialized for each device driver +that is expected to do hardware time stamping. The parameter is: + +struct hwtstamp_config { + int flags; /* no flags defined right now, must be zero */ + int tx_type; /* HWTSTAMP_TX_* */ + int rx_filter; /* HWTSTAMP_FILTER_* */ +}; + +Desired behavior is passed into the kernel and to a specific device by +calling ioctl(SIOCSHWTSTAMP) with a pointer to a struct ifreq whose +ifr_data points to a struct hwtstamp_config. The tx_type and +rx_filter are hints to the driver what it is expected to do. If +the requested fine-grained filtering for incoming packets is not +supported, the driver may time stamp more than just the requested types +of packets. + +A driver which supports hardware time stamping shall update the struct +with the actual, possibly more permissive configuration. If the +requested packets cannot be time stamped, then nothing should be +changed and ERANGE shall be returned (in contrast to EINVAL, which +indicates that SIOCSHWTSTAMP is not supported at all). + +Only a processes with admin rights may change the configuration. User +space is responsible to ensure that multiple processes don't interfere +with each other and that the settings are reset. + +/* possible values for hwtstamp_config->tx_type */ +enum { + /* + * no outgoing packet will need hardware time stamping; + * should a packet arrive which asks for it, no hardware + * time stamping will be done + */ + HWTSTAMP_TX_OFF, + + /* + * enables hardware time stamping for outgoing packets; + * the sender of the packet decides which are to be + * time stamped by setting SOF_TIMESTAMPING_TX_SOFTWARE + * before sending the packet + */ + HWTSTAMP_TX_ON, +}; + +/* possible values for hwtstamp_config->rx_filter */ +enum { + /* time stamp no incoming packet at all */ + HWTSTAMP_FILTER_NONE, + + /* time stamp any incoming packet */ + HWTSTAMP_FILTER_ALL, + + /* return value: time stamp all packets requested plus some others */ + HWTSTAMP_FILTER_SOME, + + /* PTP v1, UDP, any kind of event packet */ + HWTSTAMP_FILTER_PTP_V1_L4_EVENT, + + ... +}; + + +DEVICE IMPLEMENTATION + +A driver which supports hardware time stamping must support the +SIOCSHWTSTAMP ioctl. Time stamps for received packets must be stored +in the skb with skb_hwtstamp_set(). + +Time stamps for outgoing packets are to be generated as follows: +- In hard_start_xmit(), check if skb_hwtstamp_check_tx_hardware() + returns non-zero. If yes, then the driver is expected + to do hardware time stamping. +- If this is possible for the skb and requested, then declare + that the driver is doing the time stamping by calling + skb_hwtstamp_tx_in_progress(). A driver not supporting + hardware time stamping doesn't do that. A driver must never + touch sk_buff::tstamp! It is used to store how time stamping + for an outgoing packets is to be done. +- As soon as the driver has sent the packet and/or obtained a + hardware time stamp for it, it passes the time stamp back by + calling skb_hwtstamp_tx() with the original skb, the raw + hardware time stamp and a handle to the device (necessary + to convert the hardware time stamp to system time). If obtaining + the hardware time stamp somehow fails, then the driver should + not fall back to software time stamping. The rationale is that + this would occur at a later time in the processing pipeline + than other software time stamping and therefore could lead + to unexpected deltas between time stamps. +- If the driver did not call skb_hwtstamp_tx_in_progress(), then + dev_hard_start_xmit() checks whether software time stamping + is wanted as fallback and potentially generates the time stamp. diff --git a/Documentation/networking/timestamping/.gitignore b/Documentation/networking/timestamping/.gitignore new file mode 100644 index 00000000000..71e81eb2e22 --- /dev/null +++ b/Documentation/networking/timestamping/.gitignore @@ -0,0 +1 @@ +timestamping diff --git a/Documentation/networking/timestamping/Makefile b/Documentation/networking/timestamping/Makefile new file mode 100644 index 00000000000..2a1489fdc03 --- /dev/null +++ b/Documentation/networking/timestamping/Makefile @@ -0,0 +1,6 @@ +CPPFLAGS = -I../../../include + +timestamping: timestamping.c + +clean: + rm -f timestamping diff --git a/Documentation/networking/timestamping/timestamping.c b/Documentation/networking/timestamping/timestamping.c new file mode 100644 index 00000000000..43d14310421 --- /dev/null +++ b/Documentation/networking/timestamping/timestamping.c @@ -0,0 +1,533 @@ +/* + * This program demonstrates how the various time stamping features in + * the Linux kernel work. It emulates the behavior of a PTP + * implementation in stand-alone master mode by sending PTPv1 Sync + * multicasts once every second. It looks for similar packets, but + * beyond that doesn't actually implement PTP. + * + * Outgoing packets are time stamped with SO_TIMESTAMPING with or + * without hardware support. + * + * Incoming packets are time stamped with SO_TIMESTAMPING with or + * without hardware support, SIOCGSTAMP[NS] (per-socket time stamp) and + * SO_TIMESTAMP[NS]. + * + * Copyright (C) 2009 Intel Corporation. + * Author: Patrick Ohly + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. * See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include + +#include "asm/types.h" +#include "linux/net_tstamp.h" +#include "linux/errqueue.h" + +#ifndef SO_TIMESTAMPING +# define SO_TIMESTAMPING 37 +# define SCM_TIMESTAMPING SO_TIMESTAMPING +#endif + +#ifndef SO_TIMESTAMPNS +# define SO_TIMESTAMPNS 35 +#endif + +#ifndef SIOCGSTAMPNS +# define SIOCGSTAMPNS 0x8907 +#endif + +#ifndef SIOCSHWTSTAMP +# define SIOCSHWTSTAMP 0x89b0 +#endif + +static void usage(const char *error) +{ + if (error) + printf("invalid option: %s\n", error); + printf("timestamping interface option*\n\n" + "Options:\n" + " IP_MULTICAST_LOOP - looping outgoing multicasts\n" + " SO_TIMESTAMP - normal software time stamping, ms resolution\n" + " SO_TIMESTAMPNS - more accurate software time stamping\n" + " SOF_TIMESTAMPING_TX_HARDWARE - hardware time stamping of outgoing packets\n" + " SOF_TIMESTAMPING_TX_SOFTWARE - software fallback for outgoing packets\n" + " SOF_TIMESTAMPING_RX_HARDWARE - hardware time stamping of incoming packets\n" + " SOF_TIMESTAMPING_RX_SOFTWARE - software fallback for incoming packets\n" + " SOF_TIMESTAMPING_SOFTWARE - request reporting of software time stamps\n" + " SOF_TIMESTAMPING_SYS_HARDWARE - request reporting of transformed HW time stamps\n" + " SOF_TIMESTAMPING_RAW_HARDWARE - request reporting of raw HW time stamps\n" + " SIOCGSTAMP - check last socket time stamp\n" + " SIOCGSTAMPNS - more accurate socket time stamp\n"); + exit(1); +} + +static void bail(const char *error) +{ + printf("%s: %s\n", error, strerror(errno)); + exit(1); +} + +static const unsigned char sync[] = { + 0x00, 0x01, 0x00, 0x01, + 0x5f, 0x44, 0x46, 0x4c, + 0x54, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, + 0x01, 0x01, + + /* fake uuid */ + 0x00, 0x01, + 0x02, 0x03, 0x04, 0x05, + + 0x00, 0x01, 0x00, 0x37, + 0x00, 0x00, 0x00, 0x08, + 0x00, 0x00, 0x00, 0x00, + 0x49, 0x05, 0xcd, 0x01, + 0x29, 0xb1, 0x8d, 0xb0, + 0x00, 0x00, 0x00, 0x00, + 0x00, 0x01, + + /* fake uuid */ + 0x00, 0x01, + 0x02, 0x03, 0x04, 0x05, + + 0x00, 0x00, 0x00, 0x37, + 0x00, 0x00, 0x00, 0x04, + 0x44, 0x46, 0x4c, 0x54, + 0x00, 0x00, 0xf0, 0x60, + 0x00, 0x01, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x01, + 0x00, 0x00, 0xf0, 0x60, + 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x04, + 0x44, 0x46, 0x4c, 0x54, + 0x00, 0x01, + + /* fake uuid */ + 0x00, 0x01, + 0x02, 0x03, 0x04, 0x05, + + 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00 +}; + +static void sendpacket(int sock, struct sockaddr *addr, socklen_t addr_len) +{ + struct timeval now; + int res; + + res = sendto(sock, sync, sizeof(sync), 0, + addr, addr_len); + gettimeofday(&now, 0); + if (res < 0) + printf("%s: %s\n", "send", strerror(errno)); + else + printf("%ld.%06ld: sent %d bytes\n", + (long)now.tv_sec, (long)now.tv_usec, + res); +} + +static void printpacket(struct msghdr *msg, int res, + char *data, + int sock, int recvmsg_flags, + int siocgstamp, int siocgstampns) +{ + struct sockaddr_in *from_addr = (struct sockaddr_in *)msg->msg_name; + struct cmsghdr *cmsg; + struct timeval tv; + struct timespec ts; + struct timeval now; + + gettimeofday(&now, 0); + + printf("%ld.%06ld: received %s data, %d bytes from %s, %d bytes control messages\n", + (long)now.tv_sec, (long)now.tv_usec, + (recvmsg_flags & MSG_ERRQUEUE) ? "error" : "regular", + res, + inet_ntoa(from_addr->sin_addr), + msg->msg_controllen); + for (cmsg = CMSG_FIRSTHDR(msg); + cmsg; + cmsg = CMSG_NXTHDR(msg, cmsg)) { + printf(" cmsg len %d: ", cmsg->cmsg_len); + switch (cmsg->cmsg_level) { + case SOL_SOCKET: + printf("SOL_SOCKET "); + switch (cmsg->cmsg_type) { + case SO_TIMESTAMP: { + struct timeval *stamp = + (struct timeval *)CMSG_DATA(cmsg); + printf("SO_TIMESTAMP %ld.%06ld", + (long)stamp->tv_sec, + (long)stamp->tv_usec); + break; + } + case SO_TIMESTAMPNS: { + struct timespec *stamp = + (struct timespec *)CMSG_DATA(cmsg); + printf("SO_TIMESTAMPNS %ld.%09ld", + (long)stamp->tv_sec, + (long)stamp->tv_nsec); + break; + } + case SO_TIMESTAMPING: { + struct timespec *stamp = + (struct timespec *)CMSG_DATA(cmsg); + printf("SO_TIMESTAMPING "); + printf("SW %ld.%09ld ", + (long)stamp->tv_sec, + (long)stamp->tv_nsec); + stamp++; + printf("HW transformed %ld.%09ld ", + (long)stamp->tv_sec, + (long)stamp->tv_nsec); + stamp++; + printf("HW raw %ld.%09ld", + (long)stamp->tv_sec, + (long)stamp->tv_nsec); + break; + } + default: + printf("type %d", cmsg->cmsg_type); + break; + } + break; + case IPPROTO_IP: + printf("IPPROTO_IP "); + switch (cmsg->cmsg_type) { + case IP_RECVERR: { + struct sock_extended_err *err = + (struct sock_extended_err *)CMSG_DATA(cmsg); + printf("IP_RECVERR ee_errno '%s' ee_origin %d => %s", + strerror(err->ee_errno), + err->ee_origin, +#ifdef SO_EE_ORIGIN_TIMESTAMPING + err->ee_origin == SO_EE_ORIGIN_TIMESTAMPING ? + "bounced packet" : "unexpected origin" +#else + "probably SO_EE_ORIGIN_TIMESTAMPING" +#endif + ); + if (res < sizeof(sync)) + printf(" => truncated data?!"); + else if (!memcmp(sync, data + res - sizeof(sync), + sizeof(sync))) + printf(" => GOT OUR DATA BACK (HURRAY!)"); + break; + } + case IP_PKTINFO: { + struct in_pktinfo *pktinfo = + (struct in_pktinfo *)CMSG_DATA(cmsg); + printf("IP_PKTINFO interface index %u", + pktinfo->ipi_ifindex); + break; + } + default: + printf("type %d", cmsg->cmsg_type); + break; + } + break; + default: + printf("level %d type %d", + cmsg->cmsg_level, + cmsg->cmsg_type); + break; + } + printf("\n"); + } + + if (siocgstamp) { + if (ioctl(sock, SIOCGSTAMP, &tv)) + printf(" %s: %s\n", "SIOCGSTAMP", strerror(errno)); + else + printf("SIOCGSTAMP %ld.%06ld\n", + (long)tv.tv_sec, + (long)tv.tv_usec); + } + if (siocgstampns) { + if (ioctl(sock, SIOCGSTAMPNS, &ts)) + printf(" %s: %s\n", "SIOCGSTAMPNS", strerror(errno)); + else + printf("SIOCGSTAMPNS %ld.%09ld\n", + (long)ts.tv_sec, + (long)ts.tv_nsec); + } +} + +static void recvpacket(int sock, int recvmsg_flags, + int siocgstamp, int siocgstampns) +{ + char data[256]; + struct msghdr msg; + struct iovec entry; + struct sockaddr_in from_addr; + struct { + struct cmsghdr cm; + char control[512]; + } control; + int res; + + memset(&msg, 0, sizeof(msg)); + msg.msg_iov = &entry; + msg.msg_iovlen = 1; + entry.iov_base = data; + entry.iov_len = sizeof(data); + msg.msg_name = (caddr_t)&from_addr; + msg.msg_namelen = sizeof(from_addr); + msg.msg_control = &control; + msg.msg_controllen = sizeof(control); + + res = recvmsg(sock, &msg, recvmsg_flags|MSG_DONTWAIT); + if (res < 0) { + printf("%s %s: %s\n", + "recvmsg", + (recvmsg_flags & MSG_ERRQUEUE) ? "error" : "regular", + strerror(errno)); + } else { + printpacket(&msg, res, data, + sock, recvmsg_flags, + siocgstamp, siocgstampns); + } +} + +int main(int argc, char **argv) +{ + int so_timestamping_flags = 0; + int so_timestamp = 0; + int so_timestampns = 0; + int siocgstamp = 0; + int siocgstampns = 0; + int ip_multicast_loop = 0; + char *interface; + int i; + int enabled = 1; + int sock; + struct ifreq device; + struct ifreq hwtstamp; + struct hwtstamp_config hwconfig, hwconfig_requested; + struct sockaddr_in addr; + struct ip_mreq imr; + struct in_addr iaddr; + int val; + socklen_t len; + struct timeval next; + + if (argc < 2) + usage(0); + interface = argv[1]; + + for (i = 2; i < argc; i++) { + if (!strcasecmp(argv[i], "SO_TIMESTAMP")) + so_timestamp = 1; + else if (!strcasecmp(argv[i], "SO_TIMESTAMPNS")) + so_timestampns = 1; + else if (!strcasecmp(argv[i], "SIOCGSTAMP")) + siocgstamp = 1; + else if (!strcasecmp(argv[i], "SIOCGSTAMPNS")) + siocgstampns = 1; + else if (!strcasecmp(argv[i], "IP_MULTICAST_LOOP")) + ip_multicast_loop = 1; + else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_TX_HARDWARE")) + so_timestamping_flags |= SOF_TIMESTAMPING_TX_HARDWARE; + else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_TX_SOFTWARE")) + so_timestamping_flags |= SOF_TIMESTAMPING_TX_SOFTWARE; + else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_RX_HARDWARE")) + so_timestamping_flags |= SOF_TIMESTAMPING_RX_HARDWARE; + else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_RX_SOFTWARE")) + so_timestamping_flags |= SOF_TIMESTAMPING_RX_SOFTWARE; + else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_SOFTWARE")) + so_timestamping_flags |= SOF_TIMESTAMPING_SOFTWARE; + else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_SYS_HARDWARE")) + so_timestamping_flags |= SOF_TIMESTAMPING_SYS_HARDWARE; + else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_RAW_HARDWARE")) + so_timestamping_flags |= SOF_TIMESTAMPING_RAW_HARDWARE; + else + usage(argv[i]); + } + + sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP); + if (socket < 0) + bail("socket"); + + memset(&device, 0, sizeof(device)); + strncpy(device.ifr_name, interface, sizeof(device.ifr_name)); + if (ioctl(sock, SIOCGIFADDR, &device) < 0) + bail("getting interface IP address"); + + memset(&hwtstamp, 0, sizeof(hwtstamp)); + strncpy(hwtstamp.ifr_name, interface, sizeof(hwtstamp.ifr_name)); + hwtstamp.ifr_data = (void *)&hwconfig; + memset(&hwconfig, 0, sizeof(&hwconfig)); + hwconfig.tx_type = + (so_timestamping_flags & SOF_TIMESTAMPING_TX_HARDWARE) ? + HWTSTAMP_TX_ON : HWTSTAMP_TX_OFF; + hwconfig.rx_filter = + (so_timestamping_flags & SOF_TIMESTAMPING_RX_HARDWARE) ? + HWTSTAMP_FILTER_PTP_V1_L4_SYNC : HWTSTAMP_FILTER_NONE; + hwconfig_requested = hwconfig; + if (ioctl(sock, SIOCSHWTSTAMP, &hwtstamp) < 0) { + if ((errno == EINVAL || errno == ENOTSUP) && + hwconfig_requested.tx_type == HWTSTAMP_TX_OFF && + hwconfig_requested.rx_filter == HWTSTAMP_FILTER_NONE) + printf("SIOCSHWTSTAMP: disabling hardware time stamping not possible\n"); + else + bail("SIOCSHWTSTAMP"); + } + printf("SIOCSHWTSTAMP: tx_type %d requested, got %d; rx_filter %d requested, got %d\n", + hwconfig_requested.tx_type, hwconfig.tx_type, + hwconfig_requested.rx_filter, hwconfig.rx_filter); + + /* bind to PTP port */ + addr.sin_family = AF_INET; + addr.sin_addr.s_addr = htonl(INADDR_ANY); + addr.sin_port = htons(319 /* PTP event port */); + if (bind(sock, + (struct sockaddr *)&addr, + sizeof(struct sockaddr_in)) < 0) + bail("bind"); + + /* set multicast group for outgoing packets */ + inet_aton("224.0.1.130", &iaddr); /* alternate PTP domain 1 */ + addr.sin_addr = iaddr; + imr.imr_multiaddr.s_addr = iaddr.s_addr; + imr.imr_interface.s_addr = + ((struct sockaddr_in *)&device.ifr_addr)->sin_addr.s_addr; + if (setsockopt(sock, IPPROTO_IP, IP_MULTICAST_IF, + &imr.imr_interface.s_addr, sizeof(struct in_addr)) < 0) + bail("set multicast"); + + /* join multicast group, loop our own packet */ + if (setsockopt(sock, IPPROTO_IP, IP_ADD_MEMBERSHIP, + &imr, sizeof(struct ip_mreq)) < 0) + bail("join multicast group"); + + if (setsockopt(sock, IPPROTO_IP, IP_MULTICAST_LOOP, + &ip_multicast_loop, sizeof(enabled)) < 0) { + bail("loop multicast"); + } + + /* set socket options for time stamping */ + if (so_timestamp && + setsockopt(sock, SOL_SOCKET, SO_TIMESTAMP, + &enabled, sizeof(enabled)) < 0) + bail("setsockopt SO_TIMESTAMP"); + + if (so_timestampns && + setsockopt(sock, SOL_SOCKET, SO_TIMESTAMPNS, + &enabled, sizeof(enabled)) < 0) + bail("setsockopt SO_TIMESTAMPNS"); + + if (so_timestamping_flags && + setsockopt(sock, SOL_SOCKET, SO_TIMESTAMPING, + &so_timestamping_flags, + sizeof(so_timestamping_flags)) < 0) + bail("setsockopt SO_TIMESTAMPING"); + + /* request IP_PKTINFO for debugging purposes */ + if (setsockopt(sock, SOL_IP, IP_PKTINFO, + &enabled, sizeof(enabled)) < 0) + printf("%s: %s\n", "setsockopt IP_PKTINFO", strerror(errno)); + + /* verify socket options */ + len = sizeof(val); + if (getsockopt(sock, SOL_SOCKET, SO_TIMESTAMP, &val, &len) < 0) + printf("%s: %s\n", "getsockopt SO_TIMESTAMP", strerror(errno)); + else + printf("SO_TIMESTAMP %d\n", val); + + if (getsockopt(sock, SOL_SOCKET, SO_TIMESTAMPNS, &val, &len) < 0) + printf("%s: %s\n", "getsockopt SO_TIMESTAMPNS", + strerror(errno)); + else + printf("SO_TIMESTAMPNS %d\n", val); + + if (getsockopt(sock, SOL_SOCKET, SO_TIMESTAMPING, &val, &len) < 0) { + printf("%s: %s\n", "getsockopt SO_TIMESTAMPING", + strerror(errno)); + } else { + printf("SO_TIMESTAMPING %d\n", val); + if (val != so_timestamping_flags) + printf(" not the expected value %d\n", + so_timestamping_flags); + } + + /* send packets forever every five seconds */ + gettimeofday(&next, 0); + next.tv_sec = (next.tv_sec + 1) / 5 * 5; + next.tv_usec = 0; + while (1) { + struct timeval now; + struct timeval delta; + long delta_us; + int res; + fd_set readfs, errorfs; + + gettimeofday(&now, 0); + delta_us = (long)(next.tv_sec - now.tv_sec) * 1000000 + + (long)(next.tv_usec - now.tv_usec); + if (delta_us > 0) { + /* continue waiting for timeout or data */ + delta.tv_sec = delta_us / 1000000; + delta.tv_usec = delta_us % 1000000; + + FD_ZERO(&readfs); + FD_ZERO(&errorfs); + FD_SET(sock, &readfs); + FD_SET(sock, &errorfs); + printf("%ld.%06ld: select %ldus\n", + (long)now.tv_sec, (long)now.tv_usec, + delta_us); + res = select(sock + 1, &readfs, 0, &errorfs, &delta); + gettimeofday(&now, 0); + printf("%ld.%06ld: select returned: %d, %s\n", + (long)now.tv_sec, (long)now.tv_usec, + res, + res < 0 ? strerror(errno) : "success"); + if (res > 0) { + if (FD_ISSET(sock, &readfs)) + printf("ready for reading\n"); + if (FD_ISSET(sock, &errorfs)) + printf("has error\n"); + recvpacket(sock, 0, + siocgstamp, + siocgstampns); + recvpacket(sock, MSG_ERRQUEUE, + siocgstamp, + siocgstampns); + } + } else { + /* write one packet */ + sendpacket(sock, + (struct sockaddr *)&addr, + sizeof(addr)); + next.tv_sec += 5; + continue; + } + } + + return 0; +} -- cgit v1.2.3 From 51f31cabe3ce5345b51e4a4f82138b38c4d5dc91 Mon Sep 17 00:00:00 2001 From: Patrick Ohly Date: Thu, 12 Feb 2009 05:03:39 +0000 Subject: ip: support for TX timestamps on UDP and RAW sockets Instructions for time stamping outgoing packets are take from the socket layer and later copied into the new skb. Signed-off-by: Patrick Ohly Signed-off-by: David S. Miller --- Documentation/networking/timestamping.txt | 2 ++ 1 file changed, 2 insertions(+) (limited to 'Documentation') diff --git a/Documentation/networking/timestamping.txt b/Documentation/networking/timestamping.txt index a681a65b5bc..0e58b453917 100644 --- a/Documentation/networking/timestamping.txt +++ b/Documentation/networking/timestamping.txt @@ -56,6 +56,8 @@ and including the link layer, the scm_timestamping control message and a sock_extended_err control message with ee_errno==ENOMSG and ee_origin==SO_EE_ORIGIN_TIMESTAMPING. A socket with such a pending bounced packet is ready for reading as far as select() is concerned. +If the outgoing packet has to be fragmented, then only the first +fragment is time stamped and returned to the sending socket. All three values correspond to the same event in time, but were generated in different ways. Each of these values may be empty (= all -- cgit v1.2.3 From c844a5d38e4247fc71e371221cf762a2a44d565b Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Mon, 16 Feb 2009 23:17:33 +0100 Subject: ALSA: Fix documentation for snd-cs4236 driver Updated; removal of snd-cs4232 entry. Signed-off-by: Takashi Iwai --- Documentation/sound/alsa/ALSA-Configuration.txt | 30 +++++-------------------- 1 file changed, 5 insertions(+), 25 deletions(-) (limited to 'Documentation') diff --git a/Documentation/sound/alsa/ALSA-Configuration.txt b/Documentation/sound/alsa/ALSA-Configuration.txt index a763b76afe5..57fe4f3ca2c 100644 --- a/Documentation/sound/alsa/ALSA-Configuration.txt +++ b/Documentation/sound/alsa/ALSA-Configuration.txt @@ -391,34 +391,11 @@ Prior to version 0.9.0rc4 options had a 'snd_' prefix. This was removed. The power-management is supported. - Module snd-cs4232 - ----------------- - - Module for sound cards based on CS4232/CS4232A ISA chips. - - isapnp - ISA PnP detection - 0 = disable, 1 = enable (default) - - with isapnp=0, the following options are available: - - port - port # for CS4232 chip (PnP setup - 0x534) - cport - control port # for CS4232 chip (PnP setup - 0x120,0x210,0xf00) - mpu_port - port # for MPU-401 UART (PnP setup - 0x300), -1 = disable - fm_port - FM port # for CS4232 chip (PnP setup - 0x388), -1 = disable - irq - IRQ # for CS4232 chip (5,7,9,11,12,15) - mpu_irq - IRQ # for MPU-401 UART (9,11,12,15) - dma1 - first DMA # for CS4232 chip (0,1,3) - dma2 - second DMA # for Yamaha CS4232 chip (0,1,3), -1 = disable - - This module supports multiple cards. This module does not support autoprobe - (if ISA PnP is not used) thus main port must be specified!!! Other ports are - optional. - - The power-management is supported. - Module snd-cs4236 ----------------- - Module for sound cards based on CS4235/CS4236/CS4236B/CS4237B/ + Module for sound cards based on CS4232/CS4232A, + CS4235/CS4236/CS4236B/CS4237B/ CS4238B/CS4239 ISA chips. isapnp - ISA PnP detection - 0 = disable, 1 = enable (default) @@ -440,6 +417,9 @@ Prior to version 0.9.0rc4 options had a 'snd_' prefix. This was removed. The power-management is supported. + This module is aliased as snd-cs4232 since it provides the old + snd-cs4232 functionality, too. + Module snd-cs4281 ----------------- -- cgit v1.2.3 From 4dd3a29f295799295eac819bbf540690fbe30c16 Mon Sep 17 00:00:00 2001 From: Yoichi Yuasa Date: Wed, 18 Feb 2009 19:09:23 +0900 Subject: sound: fix opensound URL in oss Introduction Signed-off-by: Yoichi Yuasa Signed-off-by: Takashi Iwai --- Documentation/sound/oss/Introduction | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/sound/oss/Introduction b/Documentation/sound/oss/Introduction index f04ba6bb739..75d967ff926 100644 --- a/Documentation/sound/oss/Introduction +++ b/Documentation/sound/oss/Introduction @@ -80,7 +80,7 @@ Notes: additional features. 2. The commercial OSS driver may be obtained from the site: - http://www/opensound.com. This may be used for cards that + http://www.opensound.com. This may be used for cards that are unsupported by the kernel driver, or may be used by other operating systems. -- cgit v1.2.3 From eca985d28e1a8092ba2686ec5485fd688df5cfb3 Mon Sep 17 00:00:00 2001 From: Krzysztof Helt Date: Wed, 18 Feb 2009 19:07:18 +0100 Subject: sound: Remove documentation for OSS CS4232 driver There is no OSS cs4232 driver in the kernel any more and this documentation does not contain any info useful for ALSA driver. Signed-off-by: Krzysztof Helt Signed-off-by: Takashi Iwai --- Documentation/sound/oss/CS4232 | 23 ----------------------- 1 file changed, 23 deletions(-) delete mode 100644 Documentation/sound/oss/CS4232 (limited to 'Documentation') diff --git a/Documentation/sound/oss/CS4232 b/Documentation/sound/oss/CS4232 deleted file mode 100644 index 7d6af7a5c1c..00000000000 --- a/Documentation/sound/oss/CS4232 +++ /dev/null @@ -1,23 +0,0 @@ -To configure the Crystal CS423x sound chip and activate its DSP functions, -modules may be loaded in this order: - - modprobe sound - insmod ad1848 - insmod uart401 - insmod cs4232 io=* irq=* dma=* dma2=* - -This is the meaning of the parameters: - - io--I/O address of the Windows Sound System (normally 0x534) - irq--IRQ of this device - dma and dma2--DMA channels (DMA2 may be 0) - -On some cards, the board attempts to do non-PnP setup, and fails. If you -have problems, use Linux' PnP facilities. - -To get MIDI facilities add - - insmod opl3 io=* - -where "io" is the I/O address of the OPL3 synthesizer. This will be shown -in /proc/sys/pnp and is normally 0x388. -- cgit v1.2.3 From f1085c4f319f1e43c95718045a235f276cc4b615 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Fri, 20 Feb 2009 14:50:35 +0100 Subject: ALSA: hda - Update documentation for pincfg sysfs entries Added the brief descriptions of new sysfs entries for pint default config values. Signed-off-by: Takashi Iwai --- Documentation/sound/alsa/HD-Audio.txt | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/sound/alsa/HD-Audio.txt b/Documentation/sound/alsa/HD-Audio.txt index 99f7fbbe3e6..9c51e104546 100644 --- a/Documentation/sound/alsa/HD-Audio.txt +++ b/Documentation/sound/alsa/HD-Audio.txt @@ -365,10 +365,22 @@ modelname:: to this file. init_verbs:: The extra verbs to execute at initialization. You can add a verb by - writing to this file. Pass tree numbers, nid, verb and parameter. + writing to this file. Pass three numbers: nid, verb and parameter. hints:: Shows hint strings for codec parsers for any use. Right now it's not used. +init_pin_configs:: + Shows the initial pin default config values set by BIOS. +override_pin_configs:: + Shows the pin default config values to override the BIOS setup. + Writing this (with two numbers, NID and value) appends the new + value. The given will be used instead of the initial BIOS value at + the next reconfiguration time. +cur_pin_configs:: + Shows the pin default values set by the codec parser explicitly. + This doesn't show all pin values but only the changed values by + the parser. That is, if the parser doesn't change the pin default + config values by itself, this will contain nothing. reconfig:: Triggers the codec re-configuration. When any value is written to this file, the driver re-initialize and parses the codec tree -- cgit v1.2.3 From b98103a5597b87211a1c74077b06faeac554bedc Mon Sep 17 00:00:00 2001 From: Andreas Herrmann Date: Sat, 21 Feb 2009 00:09:47 +0100 Subject: x86: hpet: print HPET registers during setup (if hpet=verbose is used) Signed-off-by: Andreas Herrmann Cc: Mark Hounschell Cc: Borislav Petkov Signed-off-by: Ingo Molnar --- Documentation/kernel-parameters.txt | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index b182626739e..01379a82264 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -492,10 +492,12 @@ and is between 256 and 4096 characters. It is defined in the file Default: 64 hpet= [X86-32,HPET] option to control HPET usage - Format: { enable (default) | disable | force } + Format: { enable (default) | disable | force | + verbose } disable: disable HPET and use PIT instead force: allow force enabled of undocumented chips (ICH4, VIA, nVidia) + verbose: show contents of HPET registers during setup com20020= [HW,NET] ARCnet - COM20020 chipset Format: -- cgit v1.2.3 From c1cf8422f0512c2b14f0d66bce34abb0645c888a Mon Sep 17 00:00:00 2001 From: Stephen Hemminger Date: Fri, 20 Feb 2009 08:25:36 +0000 Subject: ip: add loose reverse path filtering Extend existing reverse path filter option to allow strict or loose filtering. (See http://en.wikipedia.org/wiki/Reverse_path_filtering). For compatibility with existing usage, the value 1 is chosen for strict mode and 2 for loose mode. Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller --- Documentation/networking/ip-sysctl.txt | 24 +++++++++++++++--------- 1 file changed, 15 insertions(+), 9 deletions(-) (limited to 'Documentation') diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index ff3f219ee4d..71041c21af9 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -699,16 +699,22 @@ accept_source_route - BOOLEAN default TRUE (router) FALSE (host) -rp_filter - BOOLEAN - 1 - do source validation by reversed path, as specified in RFC1812 - Recommended option for single homed hosts and stub network - routers. Could cause troubles for complicated (not loop free) - networks running a slow unreliable protocol (sort of RIP), - or using static routes. - +rp_filter - INTEGER 0 - No source validation. - - conf/all/rp_filter must also be set to TRUE to do source validation + 1 - Strict mode as defined in RFC3704 Strict Reverse Path + Each incoming packet is tested against the FIB and if the interface + is not the best reverse path the packet check will fail. + By default failed packets are discarded. + 2 - Loose mode as defined in RFC3704 Loose Reverse Path + Each incoming packet's source address is also tested against the FIB + and if the source address is not reachable via any interface + the packet check will fail. + + Current recommended practice in RFC3704 is to enable strict mode + to prevent IP spoofin from DDos attacks. If using asymmetric routing + or other complicated routing,t hen loose mode is recommended. + + conf/all/rp_filter must also be set to non-zero to do source validation on the interface Default value is 0. Note that some distributions enable it -- cgit v1.2.3 From 722bde6875bfb49a0c84e5601eb82dd7ac02d27c Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Mon, 23 Feb 2009 00:51:57 -0500 Subject: ext4: Add fine print for the 32000 subdirectory limit Some poeple are reading the ext4 feature list too literally and create dubious test cases involving very long filenames and 1k blocksize and then complain when they run into an htree-imposed limit. So add fine print to the "fix 32000 subdirectory limit" ext4 feature. Signed-off-by: "Theodore Ts'o" --- Documentation/filesystems/ext4.txt | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/filesystems/ext4.txt b/Documentation/filesystems/ext4.txt index cec829bc729..5c484aec2ba 100644 --- a/Documentation/filesystems/ext4.txt +++ b/Documentation/filesystems/ext4.txt @@ -85,7 +85,7 @@ Note: More extensive information for getting started with ext4 can be * extent format more robust in face of on-disk corruption due to magics, * internal redundancy in tree * improved file allocation (multi-block alloc) -* fix 32000 subdirectory limit +* lift 32000 subdirectory limit imposed by i_links_count[1] * nsec timestamps for mtime, atime, ctime, create time * inode version field on disk (NFSv4, Lustre) * reduced e2fsck time via uninit_bg feature @@ -100,6 +100,9 @@ Note: More extensive information for getting started with ext4 can be * efficent new ordered mode in JBD2 and ext4(avoid using buffer head to force the ordering) +[1] Filesystems with a block size of 1k may see a limit imposed by the +directory hash tree having a maximum depth of two. + 2.2 Candidate features for future inclusion * Online defrag (patches available but not well tested) -- cgit v1.2.3 From 346ff70fdbe9093947b9494fe714c89cafcceade Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Mon, 23 Feb 2009 09:42:57 +0100 Subject: ALSA: hda - Rename {override,cur}_pin with {user,driver}_pin Rename from override_pin and cur_pin with user_pin and driver_pin, respectively, to be a bit more intuitive. Signed-off-by: Takashi Iwai --- Documentation/sound/alsa/HD-Audio.txt | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'Documentation') diff --git a/Documentation/sound/alsa/HD-Audio.txt b/Documentation/sound/alsa/HD-Audio.txt index 9c51e104546..f590850c149 100644 --- a/Documentation/sound/alsa/HD-Audio.txt +++ b/Documentation/sound/alsa/HD-Audio.txt @@ -371,16 +371,16 @@ hints:: not used. init_pin_configs:: Shows the initial pin default config values set by BIOS. -override_pin_configs:: - Shows the pin default config values to override the BIOS setup. - Writing this (with two numbers, NID and value) appends the new - value. The given will be used instead of the initial BIOS value at - the next reconfiguration time. -cur_pin_configs:: +driver_pin_configs:: Shows the pin default values set by the codec parser explicitly. This doesn't show all pin values but only the changed values by the parser. That is, if the parser doesn't change the pin default config values by itself, this will contain nothing. +user_pin_configs:: + Shows the pin default config values to override the BIOS setup. + Writing this (with two numbers, NID and value) appends the new + value. The given will be used instead of the initial BIOS value at + the next reconfiguration time. reconfig:: Triggers the codec re-configuration. When any value is written to this file, the driver re-initialize and parses the codec tree -- cgit v1.2.3 From 5e7b8e0d87091ae21b291588817b5359a5e00795 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Mon, 23 Feb 2009 09:45:59 +0100 Subject: ALSA: hda - Make user_pin overriding the driver setup Make user_pin overriding even the driver pincfg, e.g. the static / fixed pin config table in patch_sigmatel.c. Signed-off-by: Takashi Iwai --- Documentation/sound/alsa/HD-Audio.txt | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/sound/alsa/HD-Audio.txt b/Documentation/sound/alsa/HD-Audio.txt index f590850c149..a4e5ef87af6 100644 --- a/Documentation/sound/alsa/HD-Audio.txt +++ b/Documentation/sound/alsa/HD-Audio.txt @@ -380,7 +380,8 @@ user_pin_configs:: Shows the pin default config values to override the BIOS setup. Writing this (with two numbers, NID and value) appends the new value. The given will be used instead of the initial BIOS value at - the next reconfiguration time. + the next reconfiguration time. Note that this config will override + even the driver pin configs, too. reconfig:: Triggers the codec re-configuration. When any value is written to this file, the driver re-initialize and parses the codec tree -- cgit v1.2.3 From 39c2871eeaeeddcbecee29ec905ec528a057ca52 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Mon, 23 Feb 2009 14:14:51 +0100 Subject: ALSA: hda - Add an example about pin reconfiguration Signed-off-by: Takashi Iwai --- Documentation/sound/alsa/HD-Audio.txt | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'Documentation') diff --git a/Documentation/sound/alsa/HD-Audio.txt b/Documentation/sound/alsa/HD-Audio.txt index a4e5ef87af6..99958be7b45 100644 --- a/Documentation/sound/alsa/HD-Audio.txt +++ b/Documentation/sound/alsa/HD-Audio.txt @@ -391,6 +391,14 @@ clear:: Resets the codec, removes the mixer elements and PCM stuff of the specified codec, and clear all init verbs and hints. +For example, when you want to change the pin default configuration +value of the pin widget 0x14 to 0x9993013f, and let the driver +re-configure based on that state, run like below: +------------------------------------------------------------------------ + # echo 0x14 0x9993013f > /sys/class/sound/hwC0D0/user_pin_configs + # echo 1 > /sys/class/sound/hwC0D0/reconfig +------------------------------------------------------------------------ + Power-Saving ~~~~~~~~~~~~ -- cgit v1.2.3 From bf869c30628cc02295fb919f0d0074f296d5f129 Mon Sep 17 00:00:00 2001 From: Jesper Dangaard Brouer Date: Mon, 23 Feb 2009 04:37:55 +0000 Subject: Doc: Fix typos in ip-sysctl.txt about rp_filter. First fix a typo in Stephens patch ;-) Signed-off-by: Jesper Dangaard Brouer Signed-off-by: David S. Miller --- Documentation/networking/ip-sysctl.txt | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'Documentation') diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index 71041c21af9..e0b8c2c6171 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -711,8 +711,8 @@ rp_filter - INTEGER the packet check will fail. Current recommended practice in RFC3704 is to enable strict mode - to prevent IP spoofin from DDos attacks. If using asymmetric routing - or other complicated routing,t hen loose mode is recommended. + to prevent IP spoofing from DDos attacks. If using asymmetric routing + or other complicated routing, then loose mode is recommended. conf/all/rp_filter must also be set to non-zero to do source validation on the interface -- cgit v1.2.3 From e18f5feb0c851a0e77e315b3d9ef1c432b1a50ec Mon Sep 17 00:00:00 2001 From: Jesper Dangaard Brouer Date: Mon, 23 Feb 2009 04:39:04 +0000 Subject: Doc: Cleanup whitespaces in ip-sysctl.txt Fix up whitespaces while going though ip-sysctl.txt anyway. Signed-off-by: Jesper Dangaard Brouer Signed-off-by: David S. Miller --- Documentation/networking/ip-sysctl.txt | 118 ++++++++++++++++----------------- 1 file changed, 59 insertions(+), 59 deletions(-) (limited to 'Documentation') diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index e0b8c2c6171..7185e4c41e5 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -2,7 +2,7 @@ ip_forward - BOOLEAN 0 - disabled (default) - not 0 - enabled + not 0 - enabled Forward Packets between interfaces. @@ -36,49 +36,49 @@ rt_cache_rebuild_count - INTEGER IP Fragmentation: ipfrag_high_thresh - INTEGER - Maximum memory used to reassemble IP fragments. When + Maximum memory used to reassemble IP fragments. When ipfrag_high_thresh bytes of memory is allocated for this purpose, the fragment handler will toss packets until ipfrag_low_thresh is reached. - + ipfrag_low_thresh - INTEGER - See ipfrag_high_thresh + See ipfrag_high_thresh ipfrag_time - INTEGER - Time in seconds to keep an IP fragment in memory. + Time in seconds to keep an IP fragment in memory. ipfrag_secret_interval - INTEGER - Regeneration interval (in seconds) of the hash secret (or lifetime + Regeneration interval (in seconds) of the hash secret (or lifetime for the hash secret) for IP fragments. Default: 600 ipfrag_max_dist - INTEGER - ipfrag_max_dist is a non-negative integer value which defines the - maximum "disorder" which is allowed among fragments which share a - common IP source address. Note that reordering of packets is - not unusual, but if a large number of fragments arrive from a source - IP address while a particular fragment queue remains incomplete, it - probably indicates that one or more fragments belonging to that queue - have been lost. When ipfrag_max_dist is positive, an additional check - is done on fragments before they are added to a reassembly queue - if - ipfrag_max_dist (or more) fragments have arrived from a particular IP - address between additions to any IP fragment queue using that source - address, it's presumed that one or more fragments in the queue are - lost. The existing fragment queue will be dropped, and a new one + ipfrag_max_dist is a non-negative integer value which defines the + maximum "disorder" which is allowed among fragments which share a + common IP source address. Note that reordering of packets is + not unusual, but if a large number of fragments arrive from a source + IP address while a particular fragment queue remains incomplete, it + probably indicates that one or more fragments belonging to that queue + have been lost. When ipfrag_max_dist is positive, an additional check + is done on fragments before they are added to a reassembly queue - if + ipfrag_max_dist (or more) fragments have arrived from a particular IP + address between additions to any IP fragment queue using that source + address, it's presumed that one or more fragments in the queue are + lost. The existing fragment queue will be dropped, and a new one started. An ipfrag_max_dist value of zero disables this check. Using a very small value, e.g. 1 or 2, for ipfrag_max_dist can result in unnecessarily dropping fragment queues when normal - reordering of packets occurs, which could lead to poor application - performance. Using a very large value, e.g. 50000, increases the - likelihood of incorrectly reassembling IP fragments that originate + reordering of packets occurs, which could lead to poor application + performance. Using a very large value, e.g. 50000, increases the + likelihood of incorrectly reassembling IP fragments that originate from different IP datagrams, which could result in data corruption. Default: 64 INET peer storage: inet_peer_threshold - INTEGER - The approximate size of the storage. Starting from this threshold + The approximate size of the storage. Starting from this threshold entries will be thrown aggressively. This threshold also determines entries' time-to-live and time intervals between garbage collection passes. More entries, less time-to-live, less GC interval. @@ -105,7 +105,7 @@ inet_peer_gc_maxtime - INTEGER in effect under low (or absent) memory pressure on the pool. Measured in seconds. -TCP variables: +TCP variables: somaxconn - INTEGER Limit of socket listen() backlog, known in userspace as SOMAXCONN. @@ -310,7 +310,7 @@ tcp_orphan_retries - INTEGER tcp_reordering - INTEGER Maximal reordering of packets in a TCP stream. - Default: 3 + Default: 3 tcp_retrans_collapse - BOOLEAN Bug-to-bug compatibility with some broken printers. @@ -521,7 +521,7 @@ IP Variables: ip_local_port_range - 2 INTEGERS Defines the local port range that is used by TCP and UDP to - choose the local port. The first number is the first, the + choose the local port. The first number is the first, the second the last local port number. Default value depends on amount of memory available on the system: > 128Mb 32768-61000 @@ -594,12 +594,12 @@ icmp_errors_use_inbound_ifaddr - BOOLEAN If zero, icmp error messages are sent with the primary address of the exiting interface. - + If non-zero, the message will be sent with the primary address of the interface that received the packet that caused the icmp error. This is the behaviour network many administrators will expect from a router. And it can make debugging complicated network layouts - much easier. + much easier. Note that if no primary address exists for the interface selected, then the primary address of the first non-loopback interface that @@ -611,7 +611,7 @@ igmp_max_memberships - INTEGER Change the maximum number of multicast groups we can subscribe to. Default: 20 -conf/interface/* changes special settings per interface (where "interface" is +conf/interface/* changes special settings per interface (where "interface" is the name of your network interface) conf/all/* is special, changes the settings for all interfaces @@ -625,11 +625,11 @@ log_martians - BOOLEAN accept_redirects - BOOLEAN Accept ICMP redirect messages. accept_redirects for the interface will be enabled if: - - both conf/{all,interface}/accept_redirects are TRUE in the case forwarding - for the interface is enabled + - both conf/{all,interface}/accept_redirects are TRUE in the case + forwarding for the interface is enabled or - - at least one of conf/{all,interface}/accept_redirects is TRUE in the case - forwarding for the interface is disabled + - at least one of conf/{all,interface}/accept_redirects is TRUE in the + case forwarding for the interface is disabled accept_redirects for the interface will be disabled otherwise default TRUE (host) FALSE (router) @@ -640,8 +640,8 @@ forwarding - BOOLEAN mc_forwarding - BOOLEAN Do multicast routing. The kernel needs to be compiled with CONFIG_MROUTE and a multicast routing daemon is required. - conf/all/mc_forwarding must also be set to TRUE to enable multicast routing - for the interface + conf/all/mc_forwarding must also be set to TRUE to enable multicast + routing for the interface medium_id - INTEGER Integer value used to differentiate the devices by the medium they @@ -649,7 +649,7 @@ medium_id - INTEGER the broadcast packets are received only on one of them. The default value 0 means that the device is the only interface to its medium, value of -1 means that medium is not known. - + Currently, it is used to change the proxy_arp behavior: the proxy_arp feature is enabled for packets forwarded between two devices attached to different media. @@ -710,9 +710,9 @@ rp_filter - INTEGER and if the source address is not reachable via any interface the packet check will fail. - Current recommended practice in RFC3704 is to enable strict mode + Current recommended practice in RFC3704 is to enable strict mode to prevent IP spoofing from DDos attacks. If using asymmetric routing - or other complicated routing, then loose mode is recommended. + or other complicated routing, then loose mode is recommended. conf/all/rp_filter must also be set to non-zero to do source validation on the interface @@ -835,7 +835,7 @@ apply to IPv6 [XXX?]. bindv6only - BOOLEAN Default value for IPV6_V6ONLY socket option, - which restricts use of the IPv6 socket to IPv6 communication + which restricts use of the IPv6 socket to IPv6 communication only. TRUE: disable IPv4-mapped address feature FALSE: enable IPv4-mapped address feature @@ -845,19 +845,19 @@ bindv6only - BOOLEAN IPv6 Fragmentation: ip6frag_high_thresh - INTEGER - Maximum memory used to reassemble IPv6 fragments. When + Maximum memory used to reassemble IPv6 fragments. When ip6frag_high_thresh bytes of memory is allocated for this purpose, the fragment handler will toss packets until ip6frag_low_thresh is reached. - + ip6frag_low_thresh - INTEGER - See ip6frag_high_thresh + See ip6frag_high_thresh ip6frag_time - INTEGER Time in seconds to keep an IPv6 fragment in memory. ip6frag_secret_interval - INTEGER - Regeneration interval (in seconds) of the hash secret (or lifetime + Regeneration interval (in seconds) of the hash secret (or lifetime for the hash secret) for IPv6 fragments. Default: 600 @@ -866,17 +866,17 @@ conf/default/*: conf/all/*: - Change all the interface-specific settings. + Change all the interface-specific settings. [XXX: Other special features than forwarding?] conf/all/forwarding - BOOLEAN - Enable global IPv6 forwarding between all interfaces. + Enable global IPv6 forwarding between all interfaces. - IPv4 and IPv6 work differently here; e.g. netfilter must be used + IPv4 and IPv6 work differently here; e.g. netfilter must be used to control which interfaces may forward packets and which not. - This also sets all interfaces' Host/Router setting + This also sets all interfaces' Host/Router setting 'forwarding' to the specified value. See below for details. This referred to as global forwarding. @@ -887,12 +887,12 @@ proxy_ndp - BOOLEAN conf/interface/*: Change special settings per interface. - The functional behaviour for certain settings is different + The functional behaviour for certain settings is different depending on whether local forwarding is enabled or not. accept_ra - BOOLEAN Accept Router Advertisements; autoconfigure using them. - + Functional default: enabled if local forwarding is disabled. disabled if local forwarding is enabled. @@ -938,7 +938,7 @@ accept_source_route - INTEGER Default: 0 autoconf - BOOLEAN - Autoconfigure addresses using Prefix Information in Router + Autoconfigure addresses using Prefix Information in Router Advertisements. Functional default: enabled if accept_ra_pinfo is enabled. @@ -947,11 +947,11 @@ autoconf - BOOLEAN dad_transmits - INTEGER The amount of Duplicate Address Detection probes to send. Default: 1 - + forwarding - BOOLEAN - Configure interface-specific Host/Router behaviour. + Configure interface-specific Host/Router behaviour. - Note: It is recommended to have the same setting on all + Note: It is recommended to have the same setting on all interfaces; mixed router/host scenarios are rather uncommon. FALSE: @@ -960,13 +960,13 @@ forwarding - BOOLEAN 1. IsRouter flag is not set in Neighbour Advertisements. 2. Router Solicitations are being sent when necessary. - 3. If accept_ra is TRUE (default), accept Router + 3. If accept_ra is TRUE (default), accept Router Advertisements (and do autoconfiguration). 4. If accept_redirects is TRUE (default), accept Redirects. TRUE: - If local forwarding is enabled, Router behaviour is assumed. + If local forwarding is enabled, Router behaviour is assumed. This means exactly the reverse from the above: 1. IsRouter flag is set in Neighbour Advertisements. @@ -1001,7 +1001,7 @@ router_solicitation_interval - INTEGER Default: 4 router_solicitations - INTEGER - Number of Router Solicitations to send until assuming no + Number of Router Solicitations to send until assuming no routers are present. Default: 3 @@ -1025,11 +1025,11 @@ temp_prefered_lft - INTEGER max_desync_factor - INTEGER Maximum value for DESYNC_FACTOR, which is a random value - that ensures that clients don't synchronize with each + that ensures that clients don't synchronize with each other and generate new addresses at exactly the same time. value is in seconds. Default: 600 - + regen_max_retry - INTEGER Number of attempts before give up attempting to generate valid temporary addresses. @@ -1037,8 +1037,8 @@ regen_max_retry - INTEGER max_addresses - INTEGER Number of maximum addresses per interface. 0 disables limitation. - It is recommended not set too large value (or 0) because it would - be too easy way to crash kernel to allow to create too much of + It is recommended not set too large value (or 0) because it would + be too easy way to crash kernel to allow to create too much of autoconfigured addresses. Default: 16 -- cgit v1.2.3 From ed12978453a3845c947695e7ad32bb3ede444813 Mon Sep 17 00:00:00 2001 From: Thomas Renninger Date: Wed, 4 Feb 2009 01:17:41 +0100 Subject: [CPUFREQ] Introduce /sys/devices/system/cpu/cpu*/cpufreq/cpuinfo_transition_latency It's not only useful for the ondemand and conservative governors, but also for userspace daemons to know about the HW transition latency of the CPU. It is especially useful for userspace to know about this value when the ondemand or conservative governors are run. The sampling rate control value depends on it and for userspace being able to set sane tuning values there it has to know about the transition latency. Signed-off-by: Thomas Renninger Signed-off-by: Dave Jones --- Documentation/cpu-freq/user-guide.txt | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'Documentation') diff --git a/Documentation/cpu-freq/user-guide.txt b/Documentation/cpu-freq/user-guide.txt index 917918f84fc..75f41193f3e 100644 --- a/Documentation/cpu-freq/user-guide.txt +++ b/Documentation/cpu-freq/user-guide.txt @@ -152,6 +152,18 @@ cpuinfo_min_freq : this file shows the minimum operating frequency the processor can run at(in kHz) cpuinfo_max_freq : this file shows the maximum operating frequency the processor can run at(in kHz) +cpuinfo_transition_latency The time it takes on this CPU to + switch between two frequencies in nano + seconds. If unknown or known to be + that high that the driver does not + work with the ondemand governor, -1 + (CPUFREQ_ETERNAL) will be returned. + Using this information can be useful + to choose an appropriate polling + frequency for a kernel governor or + userspace daemon. Make sure to not + switch the frequency too often + resulting in performance loss. scaling_driver : this file shows what cpufreq driver is used to set the frequency on this CPU -- cgit v1.2.3 From 9411b4ef7fcb534fe1582fe02738254e398dd931 Mon Sep 17 00:00:00 2001 From: Thomas Renninger Date: Wed, 4 Feb 2009 11:54:04 +0100 Subject: [CPUFREQ] ondemand/conservative: deprecate sampling_rate{min,max} The same info can be obtained via the transition_latency sysfs file Signed-off-by: Thomas Renninger Signed-off-by: Dave Jones --- Documentation/cpu-freq/governors.txt | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'Documentation') diff --git a/Documentation/cpu-freq/governors.txt b/Documentation/cpu-freq/governors.txt index 5b0cfa67aff..9b1851297d4 100644 --- a/Documentation/cpu-freq/governors.txt +++ b/Documentation/cpu-freq/governors.txt @@ -119,8 +119,14 @@ want the kernel to look at the CPU usage and to make decisions on what to do about the frequency. Typically this is set to values of around '10000' or more. -show_sampling_rate_(min|max): the minimum and maximum sampling rates -available that you may set 'sampling_rate' to. +show_sampling_rate_(min|max): THIS INTERFACE IS DEPRECATED, DON'T USE IT. +You can use wider ranges now and the general +cpuinfo_transition_latency variable (cmp. with user-guide.txt) can be +used to obtain exactly the same info: +show_sampling_rate_min = transtition_latency * 500 / 1000 +show_sampling_rate_max = transtition_latency * 500000 / 1000 +(divided by 1000 is to illustrate that sampling rate is in us and +transition latency is exported ns). up_threshold: defines what the average CPU usage between the samplings of 'sampling_rate' needs to be for the kernel to make a decision on -- cgit v1.2.3 From 112124ab0a9f507a0d7fdbb1e1ed2b9a24f8c4ea Mon Sep 17 00:00:00 2001 From: Thomas Renninger Date: Wed, 4 Feb 2009 11:55:12 +0100 Subject: [CPUFREQ] ondemand/conservative: sanitize sampling_rate restrictions Limit sampling rate to transition_latency * 100 or kernel limits. If sampling_rate is tried to be set too low, set the lowest allowed value. Signed-off-by: Thomas Renninger Signed-off-by: Dave Jones --- Documentation/cpu-freq/governors.txt | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/cpu-freq/governors.txt b/Documentation/cpu-freq/governors.txt index 9b1851297d4..ce73f3eb5dd 100644 --- a/Documentation/cpu-freq/governors.txt +++ b/Documentation/cpu-freq/governors.txt @@ -117,7 +117,19 @@ accessible parameters: sampling_rate: measured in uS (10^-6 seconds), this is how often you want the kernel to look at the CPU usage and to make decisions on what to do about the frequency. Typically this is set to values of -around '10000' or more. +around '10000' or more. It's default value is (cmp. with users-guide.txt): +transition_latency * 1000 +The lowest value you can set is: +transition_latency * 100 or it may get restricted to a value where it +makes not sense for the kernel anymore to poll that often which depends +on your HZ config variable (HZ=1000: max=20000us, HZ=250: max=5000). +Be aware that transition latency is in ns and sampling_rate is in us, so you +get the same sysfs value by default. +Sampling rate should always get adjusted considering the transition latency +To set the sampling rate 750 times as high as the transition latency +in the bash (as said, 1000 is default), do: +echo `$(($(cat cpuinfo_transition_latency) * 750 / 1000)) \ + >ondemand/sampling_rate show_sampling_rate_(min|max): THIS INTERFACE IS DEPRECATED, DON'T USE IT. You can use wider ranges now and the general -- cgit v1.2.3 From 9e5f6cf5f755ca5c52071c317421fae19966a658 Mon Sep 17 00:00:00 2001 From: Andreas Herrmann Date: Wed, 25 Feb 2009 11:30:45 +0100 Subject: x86: update description for memtest boot parameter Signed-off-by: Andreas Herrmann Signed-off-by: Ingo Molnar --- Documentation/kernel-parameters.txt | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index f6d5d5b9b2b..10c4b8b75c9 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1308,8 +1308,13 @@ and is between 256 and 4096 characters. It is defined in the file memtest= [KNL,X86] Enable memtest Format: - range: 0,4 : pattern number default : 0 + Specifies the number of memtest passes to be + performed. Each pass selects another test + pattern from a given set of patterns. Memtest + fills the memory with this pattern, validates + memory contents and reserves bad memory + regions that are detected. meye.*= [HW] Set MotionEye Camera parameters See Documentation/video4linux/meye.txt. -- cgit v1.2.3 From 930738de602d2ceb0d1c1b368fe2a8d2a974ab72 Mon Sep 17 00:00:00 2001 From: Clemens Ladisch Date: Thu, 26 Feb 2009 09:27:20 +0100 Subject: sound: virtuoso: add Xonar Essence STX support Add support for the Asus Xonar Essence STX sound card. Signed-off-by: Clemens Ladisch Signed-off-by: Takashi Iwai --- Documentation/sound/alsa/ALSA-Configuration.txt | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/sound/alsa/ALSA-Configuration.txt b/Documentation/sound/alsa/ALSA-Configuration.txt index 841a9365d5f..1356d2a6772 100644 --- a/Documentation/sound/alsa/ALSA-Configuration.txt +++ b/Documentation/sound/alsa/ALSA-Configuration.txt @@ -1824,7 +1824,7 @@ Prior to version 0.9.0rc4 options had a 'snd_' prefix. This was removed. ------------------- Module for sound cards based on the Asus AV100/AV200 chips, - i.e., Xonar D1, DX, D2, D2X and HDAV1.3 (Deluxe). + i.e., Xonar D1, DX, D2, D2X, HDAV1.3 (Deluxe), and Essence STX. This module supports autoprobe and multiple cards. -- cgit v1.2.3 From 1607b8ea0a4cc20752978fadb027daafc8a2d93c Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Thu, 26 Feb 2009 16:50:43 +0100 Subject: ALSA: hda - Add model=auto for STAC/IDT codecs Added the model=auto to STAC/IDT codecs to use the BIOS default setup explicitly. It can be used to disable the device-specific model quirk in the driver. Signed-off-by: Takashi Iwai --- Documentation/sound/alsa/HD-Audio-Models.txt | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'Documentation') diff --git a/Documentation/sound/alsa/HD-Audio-Models.txt b/Documentation/sound/alsa/HD-Audio-Models.txt index 0e52d273ce9..a448bbefd48 100644 --- a/Documentation/sound/alsa/HD-Audio-Models.txt +++ b/Documentation/sound/alsa/HD-Audio-Models.txt @@ -280,6 +280,7 @@ STAC9200 gateway-m4 Gateway laptops with EAPD control gateway-m4-2 Gateway laptops with EAPD control panasonic Panasonic CF-74 + auto BIOS setup (default) STAC9205/9254 ============= @@ -288,6 +289,7 @@ STAC9205/9254 dell-m43 Dell Precision dell-m44 Dell Inspiron eapd Keep EAPD on (e.g. Gateway T1616) + auto BIOS setup (default) STAC9220/9221 ============= @@ -311,6 +313,7 @@ STAC9220/9221 dell-d82 Dell (unknown) dell-m81 Dell (unknown) dell-m82 Dell XPS M1210 + auto BIOS setup (default) STAC9202/9250/9251 ================== @@ -322,6 +325,7 @@ STAC9202/9250/9251 m3 Some Gateway MX series laptops m5 Some Gateway MX series laptops (MP6954) m6 Some Gateway NX series laptops + auto BIOS setup (default) STAC9227/9228/9229/927x ======================= @@ -331,6 +335,7 @@ STAC9227/9228/9229/927x 5stack D965 5stack + SPDIF dell-3stack Dell Dimension E520 dell-bios Fixes with Dell BIOS setup + auto BIOS setup (default) STAC92HD71B* ============ @@ -339,6 +344,7 @@ STAC92HD71B* dell-m4-2 Dell desktops dell-m4-3 Dell desktops hp-m4 HP dv laptops + auto BIOS setup (default) STAC92HD73* =========== @@ -348,11 +354,13 @@ STAC92HD73* dell-m6-dmic Dell desktops/laptops with digital mics dell-m6 Dell desktops/laptops with both type of mics dell-eq Dell desktops/laptops + auto BIOS setup (default) STAC92HD83* =========== ref Reference board mic-ref Reference board with power managment for ports + auto BIOS setup (default) STAC9872 ======== -- cgit v1.2.3 From 0c5f9b8830aa0ff8f97e4efdfe1e1c4fe08ec71c Mon Sep 17 00:00:00 2001 From: Andy Grover Date: Tue, 24 Feb 2009 15:30:38 +0000 Subject: RDS: Documentation This file documents the specifics of the RDS sockets API, as well as covering some of the details of its internal implementation. Signed-off-by: Andy Grover Signed-off-by: David S. Miller --- Documentation/networking/rds.txt | 356 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 356 insertions(+) create mode 100644 Documentation/networking/rds.txt (limited to 'Documentation') diff --git a/Documentation/networking/rds.txt b/Documentation/networking/rds.txt new file mode 100644 index 00000000000..c67077cbeb8 --- /dev/null +++ b/Documentation/networking/rds.txt @@ -0,0 +1,356 @@ + +Overview +======== + +This readme tries to provide some background on the hows and whys of RDS, +and will hopefully help you find your way around the code. + +In addition, please see this email about RDS origins: +http://oss.oracle.com/pipermail/rds-devel/2007-November/000228.html + +RDS Architecture +================ + +RDS provides reliable, ordered datagram delivery by using a single +reliable connection between any two nodes in the cluster. This allows +applications to use a single socket to talk to any other process in the +cluster - so in a cluster with N processes you need N sockets, in contrast +to N*N if you use a connection-oriented socket transport like TCP. + +RDS is not Infiniband-specific; it was designed to support different +transports. The current implementation used to support RDS over TCP as well +as IB. Work is in progress to support RDS over iWARP, and using DCE to +guarantee no dropped packets on Ethernet, it may be possible to use RDS over +UDP in the future. + +The high-level semantics of RDS from the application's point of view are + + * Addressing + RDS uses IPv4 addresses and 16bit port numbers to identify + the end point of a connection. All socket operations that involve + passing addresses between kernel and user space generally + use a struct sockaddr_in. + + The fact that IPv4 addresses are used does not mean the underlying + transport has to be IP-based. In fact, RDS over IB uses a + reliable IB connection; the IP address is used exclusively to + locate the remote node's GID (by ARPing for the given IP). + + The port space is entirely independent of UDP, TCP or any other + protocol. + + * Socket interface + RDS sockets work *mostly* as you would expect from a BSD + socket. The next section will cover the details. At any rate, + all I/O is performed through the standard BSD socket API. + Some additions like zerocopy support are implemented through + control messages, while other extensions use the getsockopt/ + setsockopt calls. + + Sockets must be bound before you can send or receive data. + This is needed because binding also selects a transport and + attaches it to the socket. Once bound, the transport assignment + does not change. RDS will tolerate IPs moving around (eg in + a active-active HA scenario), but only as long as the address + doesn't move to a different transport. + + * sysctls + RDS supports a number of sysctls in /proc/sys/net/rds + + +Socket Interface +================ + + AF_RDS, PF_RDS, SOL_RDS + These constants haven't been assigned yet, because RDS isn't in + mainline yet. Currently, the kernel module assigns some constant + and publishes it to user space through two sysctl files + /proc/sys/net/rds/pf_rds + /proc/sys/net/rds/sol_rds + + fd = socket(PF_RDS, SOCK_SEQPACKET, 0); + This creates a new, unbound RDS socket. + + setsockopt(SOL_SOCKET): send and receive buffer size + RDS honors the send and receive buffer size socket options. + You are not allowed to queue more than SO_SNDSIZE bytes to + a socket. A message is queued when sendmsg is called, and + it leaves the queue when the remote system acknowledges + its arrival. + + The SO_RCVSIZE option controls the maximum receive queue length. + This is a soft limit rather than a hard limit - RDS will + continue to accept and queue incoming messages, even if that + takes the queue length over the limit. However, it will also + mark the port as "congested" and send a congestion update to + the source node. The source node is supposed to throttle any + processes sending to this congested port. + + bind(fd, &sockaddr_in, ...) + This binds the socket to a local IP address and port, and a + transport. + + sendmsg(fd, ...) + Sends a message to the indicated recipient. The kernel will + transparently establish the underlying reliable connection + if it isn't up yet. + + An attempt to send a message that exceeds SO_SNDSIZE will + return with -EMSGSIZE + + An attempt to send a message that would take the total number + of queued bytes over the SO_SNDSIZE threshold will return + EAGAIN. + + An attempt to send a message to a destination that is marked + as "congested" will return ENOBUFS. + + recvmsg(fd, ...) + Receives a message that was queued to this socket. The sockets + recv queue accounting is adjusted, and if the queue length + drops below SO_SNDSIZE, the port is marked uncongested, and + a congestion update is sent to all peers. + + Applications can ask the RDS kernel module to receive + notifications via control messages (for instance, there is a + notification when a congestion update arrived, or when a RDMA + operation completes). These notifications are received through + the msg.msg_control buffer of struct msghdr. The format of the + messages is described in manpages. + + poll(fd) + RDS supports the poll interface to allow the application + to implement async I/O. + + POLLIN handling is pretty straightforward. When there's an + incoming message queued to the socket, or a pending notification, + we signal POLLIN. + + POLLOUT is a little harder. Since you can essentially send + to any destination, RDS will always signal POLLOUT as long as + there's room on the send queue (ie the number of bytes queued + is less than the sendbuf size). + + However, the kernel will refuse to accept messages to + a destination marked congested - in this case you will loop + forever if you rely on poll to tell you what to do. + This isn't a trivial problem, but applications can deal with + this - by using congestion notifications, and by checking for + ENOBUFS errors returned by sendmsg. + + setsockopt(SOL_RDS, RDS_CANCEL_SENT_TO, &sockaddr_in) + This allows the application to discard all messages queued to a + specific destination on this particular socket. + + This allows the application to cancel outstanding messages if + it detects a timeout. For instance, if it tried to send a message, + and the remote host is unreachable, RDS will keep trying forever. + The application may decide it's not worth it, and cancel the + operation. In this case, it would use RDS_CANCEL_SENT_TO to + nuke any pending messages. + + +RDMA for RDS +============ + + see rds-rdma(7) manpage (available in rds-tools) + + +Congestion Notifications +======================== + + see rds(7) manpage + + +RDS Protocol +============ + + Message header + + The message header is a 'struct rds_header' (see rds.h): + Fields: + h_sequence: + per-packet sequence number + h_ack: + piggybacked acknowledgment of last packet received + h_len: + length of data, not including header + h_sport: + source port + h_dport: + destination port + h_flags: + CONG_BITMAP - this is a congestion update bitmap + ACK_REQUIRED - receiver must ack this packet + RETRANSMITTED - packet has previously been sent + h_credit: + indicate to other end of connection that + it has more credits available (i.e. there is + more send room) + h_padding[4]: + unused, for future use + h_csum: + header checksum + h_exthdr: + optional data can be passed here. This is currently used for + passing RDMA-related information. + + ACK and retransmit handling + + One might think that with reliable IB connections you wouldn't need + to ack messages that have been received. The problem is that IB + hardware generates an ack message before it has DMAed the message + into memory. This creates a potential message loss if the HCA is + disabled for any reason between when it sends the ack and before + the message is DMAed and processed. This is only a potential issue + if another HCA is available for fail-over. + + Sending an ack immediately would allow the sender to free the sent + message from their send queue quickly, but could cause excessive + traffic to be used for acks. RDS piggybacks acks on sent data + packets. Ack-only packets are reduced by only allowing one to be + in flight at a time, and by the sender only asking for acks when + its send buffers start to fill up. All retransmissions are also + acked. + + Flow Control + + RDS's IB transport uses a credit-based mechanism to verify that + there is space in the peer's receive buffers for more data. This + eliminates the need for hardware retries on the connection. + + Congestion + + Messages waiting in the receive queue on the receiving socket + are accounted against the sockets SO_RCVBUF option value. Only + the payload bytes in the message are accounted for. If the + number of bytes queued equals or exceeds rcvbuf then the socket + is congested. All sends attempted to this socket's address + should return block or return -EWOULDBLOCK. + + Applications are expected to be reasonably tuned such that this + situation very rarely occurs. An application encountering this + "back-pressure" is considered a bug. + + This is implemented by having each node maintain bitmaps which + indicate which ports on bound addresses are congested. As the + bitmap changes it is sent through all the connections which + terminate in the local address of the bitmap which changed. + + The bitmaps are allocated as connections are brought up. This + avoids allocation in the interrupt handling path which queues + sages on sockets. The dense bitmaps let transports send the + entire bitmap on any bitmap change reasonably efficiently. This + is much easier to implement than some finer-grained + communication of per-port congestion. The sender does a very + inexpensive bit test to test if the port it's about to send to + is congested or not. + + +RDS Transport Layer +================== + + As mentioned above, RDS is not IB-specific. Its code is divided + into a general RDS layer and a transport layer. + + The general layer handles the socket API, congestion handling, + loopback, stats, usermem pinning, and the connection state machine. + + The transport layer handles the details of the transport. The IB + transport, for example, handles all the queue pairs, work requests, + CM event handlers, and other Infiniband details. + + +RDS Kernel Structures +===================== + + struct rds_message + aka possibly "rds_outgoing", the generic RDS layer copies data to + be sent and sets header fields as needed, based on the socket API. + This is then queued for the individual connection and sent by the + connection's transport. + struct rds_incoming + a generic struct referring to incoming data that can be handed from + the transport to the general code and queued by the general code + while the socket is awoken. It is then passed back to the transport + code to handle the actual copy-to-user. + struct rds_socket + per-socket information + struct rds_connection + per-connection information + struct rds_transport + pointers to transport-specific functions + struct rds_statistics + non-transport-specific statistics + struct rds_cong_map + wraps the raw congestion bitmap, contains rbnode, waitq, etc. + +Connection management +===================== + + Connections may be in UP, DOWN, CONNECTING, DISCONNECTING, and + ERROR states. + + The first time an attempt is made by an RDS socket to send data to + a node, a connection is allocated and connected. That connection is + then maintained forever -- if there are transport errors, the + connection will be dropped and re-established. + + Dropping a connection while packets are queued will cause queued or + partially-sent datagrams to be retransmitted when the connection is + re-established. + + +The send path +============= + + rds_sendmsg() + struct rds_message built from incoming data + CMSGs parsed (e.g. RDMA ops) + transport connection alloced and connected if not already + rds_message placed on send queue + send worker awoken + rds_send_worker() + calls rds_send_xmit() until queue is empty + rds_send_xmit() + transmits congestion map if one is pending + may set ACK_REQUIRED + calls transport to send either non-RDMA or RDMA message + (RDMA ops never retransmitted) + rds_ib_xmit() + allocs work requests from send ring + adds any new send credits available to peer (h_credits) + maps the rds_message's sg list + piggybacks ack + populates work requests + post send to connection's queue pair + +The recv path +============= + + rds_ib_recv_cq_comp_handler() + looks at write completions + unmaps recv buffer from device + no errors, call rds_ib_process_recv() + refill recv ring + rds_ib_process_recv() + validate header checksum + copy header to rds_ib_incoming struct if start of a new datagram + add to ibinc's fraglist + if competed datagram: + update cong map if datagram was cong update + call rds_recv_incoming() otherwise + note if ack is required + rds_recv_incoming() + drop duplicate packets + respond to pings + find the sock associated with this datagram + add to sock queue + wake up sock + do some congestion calculations + rds_recvmsg + copy data into user iovec + handle CMSGs + return to application + + -- cgit v1.2.3 From 72fd455ba54b5a02b9c74221b9ded8b1845b464a Mon Sep 17 00:00:00 2001 From: Wang Chen Date: Mon, 2 Mar 2009 13:55:14 +0800 Subject: sched, documentation: remove old O(1) scheduler document Since we don't have O(1) scheduler implementation anymore, remove the legacy doc. Signed-off-by: Wang Chen Signed-off-by: Ingo Molnar --- Documentation/scheduler/00-INDEX | 2 - Documentation/scheduler/sched-coding.txt | 126 ------------------------------- 2 files changed, 128 deletions(-) delete mode 100644 Documentation/scheduler/sched-coding.txt (limited to 'Documentation') diff --git a/Documentation/scheduler/00-INDEX b/Documentation/scheduler/00-INDEX index aabcc3a089b..3c00c9c3219 100644 --- a/Documentation/scheduler/00-INDEX +++ b/Documentation/scheduler/00-INDEX @@ -2,8 +2,6 @@ - this file. sched-arch.txt - CPU Scheduler implementation hints for architecture specific code. -sched-coding.txt - - reference for various scheduler-related methods in the O(1) scheduler. sched-design-CFS.txt - goals, design and implementation of the Complete Fair Scheduler. sched-domains.txt diff --git a/Documentation/scheduler/sched-coding.txt b/Documentation/scheduler/sched-coding.txt deleted file mode 100644 index cbd8db752ac..00000000000 --- a/Documentation/scheduler/sched-coding.txt +++ /dev/null @@ -1,126 +0,0 @@ - Reference for various scheduler-related methods in the O(1) scheduler - Robert Love , MontaVista Software - - -Note most of these methods are local to kernel/sched.c - this is by design. -The scheduler is meant to be self-contained and abstracted away. This document -is primarily for understanding the scheduler, not interfacing to it. Some of -the discussed interfaces, however, are general process/scheduling methods. -They are typically defined in include/linux/sched.h. - - -Main Scheduling Methods ------------------------ - -void load_balance(runqueue_t *this_rq, int idle) - Attempts to pull tasks from one cpu to another to balance cpu usage, - if needed. This method is called explicitly if the runqueues are - imbalanced or periodically by the timer tick. Prior to calling, - the current runqueue must be locked and interrupts disabled. - -void schedule() - The main scheduling function. Upon return, the highest priority - process will be active. - - -Locking -------- - -Each runqueue has its own lock, rq->lock. When multiple runqueues need -to be locked, lock acquires must be ordered by ascending &runqueue value. - -A specific runqueue is locked via - - task_rq_lock(task_t pid, unsigned long *flags) - -which disables preemption, disables interrupts, and locks the runqueue pid is -running on. Likewise, - - task_rq_unlock(task_t pid, unsigned long *flags) - -unlocks the runqueue pid is running on, restores interrupts to their previous -state, and reenables preemption. - -The routines - - double_rq_lock(runqueue_t *rq1, runqueue_t *rq2) - -and - - double_rq_unlock(runqueue_t *rq1, runqueue_t *rq2) - -safely lock and unlock, respectively, the two specified runqueues. They do -not, however, disable and restore interrupts. Users are required to do so -manually before and after calls. - - -Values ------- - -MAX_PRIO - The maximum priority of the system, stored in the task as task->prio. - Lower priorities are higher. Normal (non-RT) priorities range from - MAX_RT_PRIO to (MAX_PRIO - 1). -MAX_RT_PRIO - The maximum real-time priority of the system. Valid RT priorities - range from 0 to (MAX_RT_PRIO - 1). -MAX_USER_RT_PRIO - The maximum real-time priority that is exported to user-space. Should - always be equal to or less than MAX_RT_PRIO. Setting it less allows - kernel threads to have higher priorities than any user-space task. -MIN_TIMESLICE -MAX_TIMESLICE - Respectively, the minimum and maximum timeslices (quanta) of a process. - -Data ----- - -struct runqueue - The main per-CPU runqueue data structure. -struct task_struct - The main per-process data structure. - - -General Methods ---------------- - -cpu_rq(cpu) - Returns the runqueue of the specified cpu. -this_rq() - Returns the runqueue of the current cpu. -task_rq(pid) - Returns the runqueue which holds the specified pid. -cpu_curr(cpu) - Returns the task currently running on the given cpu. -rt_task(pid) - Returns true if pid is real-time, false if not. - - -Process Control Methods ------------------------ - -void set_user_nice(task_t *p, long nice) - Sets the "nice" value of task p to the given value. -int setscheduler(pid_t pid, int policy, struct sched_param *param) - Sets the scheduling policy and parameters for the given pid. -int set_cpus_allowed(task_t *p, unsigned long new_mask) - Sets a given task's CPU affinity and migrates it to a proper cpu. - Callers must have a valid reference to the task and assure the - task not exit prematurely. No locks can be held during the call. -set_task_state(tsk, state_value) - Sets the given task's state to the given value. -set_current_state(state_value) - Sets the current task's state to the given value. -void set_tsk_need_resched(struct task_struct *tsk) - Sets need_resched in the given task. -void clear_tsk_need_resched(struct task_struct *tsk) - Clears need_resched in the given task. -void set_need_resched() - Sets need_resched in the current task. -void clear_need_resched() - Clears need_resched in the current task. -int need_resched() - Returns true if need_resched is set in the current task, false - otherwise. -yield() - Place the current process at the end of the runqueue and call schedule. -- cgit v1.2.3 From d02b1f3910f12cfe377a31afebcbbde4f5664b74 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Mon, 2 Mar 2009 17:34:51 +0100 Subject: ALSA: hda - Update documetation for hints sysfs entry Signed-off-by: Takashi Iwai --- Documentation/sound/alsa/HD-Audio.txt | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) (limited to 'Documentation') diff --git a/Documentation/sound/alsa/HD-Audio.txt b/Documentation/sound/alsa/HD-Audio.txt index 99958be7b45..c5948f2f9a2 100644 --- a/Documentation/sound/alsa/HD-Audio.txt +++ b/Documentation/sound/alsa/HD-Audio.txt @@ -365,10 +365,13 @@ modelname:: to this file. init_verbs:: The extra verbs to execute at initialization. You can add a verb by - writing to this file. Pass three numbers: nid, verb and parameter. + writing to this file. Pass three numbers: nid, verb and parameter + (separated with a space). hints:: - Shows hint strings for codec parsers for any use. Right now it's - not used. + Shows / stores hint strings for codec parsers for any use. + Its format is `key = value`. For example, passing `hp_detect = yes` + to IDT/STAC codec parser will result in the disablement of the + headphone detection. init_pin_configs:: Shows the initial pin default config values set by BIOS. driver_pin_configs:: -- cgit v1.2.3 From 79d7d5333b598e9a559bf27833f0ad2b8bf6ad2c Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Wed, 4 Mar 2009 09:03:50 +0100 Subject: ALSA: hda - Fix HP dv6736 mic input Fix the mic input of HP dv6736 with Conexant 5051 codec chip. This laptop seems have no mic-switching per jack connection. A new model hp-dv6736 is introduced to match with the h/w implementation. Reference: Novell bnc#480753 https://bugzilla.novell.com/show_bug.cgi?id=480753 Signed-off-by: Takashi Iwai --- Documentation/sound/alsa/HD-Audio-Models.txt | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/sound/alsa/HD-Audio-Models.txt b/Documentation/sound/alsa/HD-Audio-Models.txt index a448bbefd48..80b796e4a80 100644 --- a/Documentation/sound/alsa/HD-Audio-Models.txt +++ b/Documentation/sound/alsa/HD-Audio-Models.txt @@ -262,6 +262,7 @@ Conexant 5051 ============= laptop Basic Laptop config (default) hp HP Spartan laptop + hp-dv6736 HP dv6736 lenovo-x200 Lenovo X200 laptop STAC9200 -- cgit v1.2.3 From 3197ebdb130473a92760100cbfe0d7e671838f48 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Tue, 31 Mar 2009 09:10:09 -0400 Subject: ext4: Add sysfs support Add basic sysfs support so that information about the mounted filesystem and various tuning parameters can be accessed via /sys/fs/ext4//*. Signed-off-by: "Theodore Ts'o" --- Documentation/ABI/testing/sysfs-fs-ext4 | 81 +++++++++++++++++++++++++++++++++ 1 file changed, 81 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-fs-ext4 (limited to 'Documentation') diff --git a/Documentation/ABI/testing/sysfs-fs-ext4 b/Documentation/ABI/testing/sysfs-fs-ext4 new file mode 100644 index 00000000000..4e79074de28 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-fs-ext4 @@ -0,0 +1,81 @@ +What: /sys/fs/ext4//mb_stats +Date: March 2008 +Contact: "Theodore Ts'o" +Description: + Controls whether the multiblock allocator should + collect statistics, which are shown during the unmount. + 1 means to collect statistics, 0 means not to collect + statistics + +What: /sys/fs/ext4//mb_group_prealloc +Date: March 2008 +Contact: "Theodore Ts'o" +Description: + The multiblock allocator will round up allocation + requests to a multiple of this tuning parameter if the + stripe size is not set in the ext4 superblock + +What: /sys/fs/ext4//mb_max_to_scan +Date: March 2008 +Contact: "Theodore Ts'o" +Description: + The maximum number of extents the multiblock allocator + will search to find the best extent + +What: /sys/fs/ext4//mb_min_to_scan +Date: March 2008 +Contact: "Theodore Ts'o" +Description: + The minimum number of extents the multiblock allocator + will search to find the best extent + +What: /sys/fs/ext4//mb_order2_req +Date: March 2008 +Contact: "Theodore Ts'o" +Description: + Tuning parameter which controls the minimum size for + requests (as a power of 2) where the buddy cache is + used + +What: /sys/fs/ext4//mb_stream_req +Date: March 2008 +Contact: "Theodore Ts'o" +Description: + Files which have fewer blocks than this tunable + parameter will have their blocks allocated out of a + block group specific preallocation pool, so that small + files are packed closely together. Each large file + will have its blocks allocated out of its own unique + preallocation pool. + +What: /sys/fs/ext4//inode_readahead +Date: March 2008 +Contact: "Theodore Ts'o" +Description: + Tuning parameter which controls the maximum number of + inode table blocks that ext4's inode table readahead + algorithm will pre-read into the buffer cache + +What: /sys/fs/ext4//delayed_allocation_blocks +Date: March 2008 +Contact: "Theodore Ts'o" +Description: + This file is read-only and shows the number of blocks + that are dirty in the page cache, but which do not + have their location in the filesystem allocated yet. + +What: /sys/fs/ext4//lifetime_write_kbytes +Date: March 2008 +Contact: "Theodore Ts'o" +Description: + This file is read-only and shows the number of kilobytes + of data that have been written to this filesystem since it was + created. + +What: /sys/fs/ext4//session_write_kbytes +Date: March 2008 +Contact: "Theodore Ts'o" +Description: + This file is read-only and shows the number of + kilobytes of data that have been written to this + filesystem since it was mounted. -- cgit v1.2.3 From b713a5ec55bf73c833f9883cdd761b20ee61a1ab Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Tue, 31 Mar 2009 09:11:14 -0400 Subject: ext4: remove /proc tuning knobs Remove tuning knobs in /proc/fs/ext4//*. Signed-off-by: "Theodore Ts'o" --- Documentation/filesystems/proc.txt | 21 --------------------- 1 file changed, 21 deletions(-) (limited to 'Documentation') diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index 830bad7cce0..efc4fd9f40c 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -940,27 +940,6 @@ Table 1-10: Files in /proc/fs/ext4/ File Content mb_groups details of multiblock allocator buddy cache of free blocks mb_history multiblock allocation history - stats controls whether the multiblock allocator should start - collecting statistics, which are shown during the unmount - group_prealloc the multiblock allocator will round up allocation - requests to a multiple of this tuning parameter if the - stripe size is not set in the ext4 superblock - max_to_scan The maximum number of extents the multiblock allocator - will search to find the best extent - min_to_scan The minimum number of extents the multiblock allocator - will search to find the best extent - order2_req Tuning parameter which controls the minimum size for - requests (as a power of 2) where the buddy cache is - used - stream_req Files which have fewer blocks than this tunable - parameter will have their blocks allocated out of a - block group specific preallocation pool, so that small - files are packed closely together. Each large file - will have its blocks allocated out of its own unique - preallocation pool. -inode_readahead Tuning parameter which controls the maximum number of - inode table blocks that ext4's inode table readahead - algorithm will pre-read into the buffer cache .............................................................................. -- cgit v1.2.3 From a1aade478862fca8710904532cbc6efed97fd05a Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Wed, 4 Mar 2009 16:11:35 -0800 Subject: x86/doc: mini-howto for using earlyprintk=dbgp [ mingo: small edits and extensions. ] Signed-off-by: Yinghai Lu Cc: "Eric W. Biederman" Cc: Greg KH Cc: Randy Dunlap Cc: Alan Stern Cc: Sarah Sharp Cc: Andrew Morton LKML-Reference: <49AF18B7.4050305@kernel.org> Signed-off-by: Ingo Molnar --- Documentation/x86/earlyprintk.txt | 101 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 101 insertions(+) create mode 100644 Documentation/x86/earlyprintk.txt (limited to 'Documentation') diff --git a/Documentation/x86/earlyprintk.txt b/Documentation/x86/earlyprintk.txt new file mode 100644 index 00000000000..607b1a01606 --- /dev/null +++ b/Documentation/x86/earlyprintk.txt @@ -0,0 +1,101 @@ + +Mini-HOWTO for using the earlyprintk=dbgp boot option with a +USB2 Debug port key and a debug cable, on x86 systems. + +You need two computers, the 'USB debug key' special gadget and +and two USB cables, connected like this: + + [host/target] <-------> [USB debug key] <-------> [client/console] + +1. There are three specific hardware requirements: + + a.) Host/target system needs to have USB debug port capability. + + You can check this capability by looking at a 'Debug port' bit in + the lspci -vvv output: + + # lspci -vvv + ... + 00:1d.7 USB Controller: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #1 (rev 03) (prog-if 20 [EHCI]) + Subsystem: Lenovo ThinkPad T61 + Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR+ FastB2B- DisINTx- + Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- SERR- /proc/sysrq-trigger + + On the host/target system you should see this help line in "dmesg" output: + + SysRq : HELP : loglevel(0-9) reBoot Crashdump terminate-all-tasks(E) memory-full-oom-kill(F) kill-all-tasks(I) saK show-backtrace-all-active-cpus(L) show-memory-usage(M) nice-all-RT-tasks(N) powerOff show-registers(P) show-all-timers(Q) unRaw Sync show-task-states(T) Unmount show-blocked-tasks(W) dump-ftrace-buffer(Z) + + On the client/console system do: + + cat /dev/ttyUSB0 + + And you should see the help line above displayed shortly after you've + provoked it on the host system. + +If it does not work then please ask about it on the linux-kernel@vger.kernel.org +mailing list or contact the x86 maintainers. -- cgit v1.2.3 From 59d3daafa17265f01149df8eab3fb69b9b42cb2e Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Fri, 9 Jan 2009 13:01:56 +0100 Subject: dma-debug: add kernel command line parameters Impact: add dma_debug= and dma_debug_entries= kernel parameters Signed-off-by: Joerg Roedel --- Documentation/kernel-parameters.txt | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'Documentation') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 54f21a5c262..0fa3c054599 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -491,6 +491,16 @@ and is between 256 and 4096 characters. It is defined in the file Range: 0 - 8192 Default: 64 + dma_debug=off If the kernel is compiled with DMA_API_DEBUG support + this option disables the debugging code at boot. + + dma_debug_entries= + This option allows to tune the number of preallocated + entries for DMA-API debugging code. One entry is + required per DMA-API allocation. Use this if the + DMA-API debugging code disables itself because the + architectural default is too low. + hpet= [X86-32,HPET] option to control HPET usage Format: { enable (default) | disable | force } disable: disable HPET and use PIT instead -- cgit v1.2.3 From 4e59c25dcbc1f033d043f1009a7f6aaa1f2aef26 Mon Sep 17 00:00:00 2001 From: Ben Dooks Date: Fri, 12 Dec 2008 00:24:18 +0000 Subject: [ARM] S3C: Rename s3c2410_pm_init to s3c_pm_init. Since we have moved a large proportion of the PM code to the common support area, remove the cpu specific name from the initialisation function. Signed-off-by: Ben Dooks --- Documentation/arm/Samsung-S3C24XX/Suspend.txt | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'Documentation') diff --git a/Documentation/arm/Samsung-S3C24XX/Suspend.txt b/Documentation/arm/Samsung-S3C24XX/Suspend.txt index 0dab6e32c13..a30fe510572 100644 --- a/Documentation/arm/Samsung-S3C24XX/Suspend.txt +++ b/Documentation/arm/Samsung-S3C24XX/Suspend.txt @@ -40,13 +40,13 @@ Resuming Machine Support --------------- - The machine specific functions must call the s3c2410_pm_init() function + The machine specific functions must call the s3c_pm_init() function to say that its bootloader is capable of resuming. This can be as simple as adding the following to the machine's definition: - INITMACHINE(s3c2410_pm_init) + INITMACHINE(s3c_pm_init) - A board can do its own setup before calling s3c2410_pm_init, if it + A board can do its own setup before calling s3c_pm_init, if it needs to setup anything else for power management support. There is currently no support for over-riding the default method of @@ -74,7 +74,7 @@ statuc void __init machine_init(void) enable_irq_wake(IRQ_EINT0); - s3c2410_pm_init(); + s3c_pm_init(); } -- cgit v1.2.3 From 79c7cdd5441f5d3900c1632adcc8cd2bee35c8da Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Mon, 9 Feb 2009 14:47:19 +0100 Subject: ALSA: Add kernel-doc comments to vmaster stuff Signed-off-by: Takashi Iwai --- Documentation/sound/alsa/DocBook/alsa-driver-api.tmpl | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'Documentation') diff --git a/Documentation/sound/alsa/DocBook/alsa-driver-api.tmpl b/Documentation/sound/alsa/DocBook/alsa-driver-api.tmpl index 9d644f7e241..115962827c8 100644 --- a/Documentation/sound/alsa/DocBook/alsa-driver-api.tmpl +++ b/Documentation/sound/alsa/DocBook/alsa-driver-api.tmpl @@ -71,6 +71,10 @@ !Esound/pci/ac97/ac97_codec.c !Esound/pci/ac97/ac97_pcm.c + Virtual Master Control API +!Esound/core/vmaster.c +!Iinclude/sound/control.h + MIDI API Raw MIDI API -- cgit v1.2.3 From 662c319ae4b4fb60001816dfe1dde5fdfc7a2af9 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Mon, 9 Feb 2009 08:53:50 +0100 Subject: ALSA: Add sound/core/jack.c to driver-API docbook entry Signed-off-by: Takashi Iwai --- Documentation/sound/alsa/DocBook/alsa-driver-api.tmpl | 3 +++ 1 file changed, 3 insertions(+) (limited to 'Documentation') diff --git a/Documentation/sound/alsa/DocBook/alsa-driver-api.tmpl b/Documentation/sound/alsa/DocBook/alsa-driver-api.tmpl index 9d644f7e241..37b006cdf2f 100644 --- a/Documentation/sound/alsa/DocBook/alsa-driver-api.tmpl +++ b/Documentation/sound/alsa/DocBook/alsa-driver-api.tmpl @@ -88,6 +88,9 @@ Miscellaneous Functions Hardware-Dependent Devices API !Esound/core/hwdep.c + + Jack Abstraction Layer API +!Esound/core/jack.c ISA DMA Helpers !Esound/core/isadma.c -- cgit v1.2.3 From 5f8206c04857965cc2ff6c395633c4fdd977dd77 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Mon, 9 Feb 2009 08:50:43 +0100 Subject: ALSA: Fix DocBook headers Signed-off-by: Takashi Iwai --- Documentation/sound/alsa/DocBook/alsa-driver-api.tmpl | 10 ++++++---- Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl | 8 ++++---- 2 files changed, 10 insertions(+), 8 deletions(-) (limited to 'Documentation') diff --git a/Documentation/sound/alsa/DocBook/alsa-driver-api.tmpl b/Documentation/sound/alsa/DocBook/alsa-driver-api.tmpl index 90f163c4bde..0230a96f056 100644 --- a/Documentation/sound/alsa/DocBook/alsa-driver-api.tmpl +++ b/Documentation/sound/alsa/DocBook/alsa-driver-api.tmpl @@ -1,11 +1,11 @@ - - - - + + + The ALSA Driver API @@ -35,6 +35,8 @@ + + Management of Cards and Devices Card Management !Esound/core/init.c diff --git a/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl b/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl index 320384c1791..46b08fef374 100644 --- a/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl +++ b/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl @@ -1,11 +1,11 @@ - - - - + + + Writing an ALSA Driver -- cgit v1.2.3 From e776ec19a47a325ee1d9ece2d983526dcd626c53 Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Sat, 28 Feb 2009 17:40:18 +0100 Subject: ALSA: Move ALSA docbooks to be with the rest of the kernel docbooks Move ALSA docbooks to be with the rest of the kernel docbooks and add them to the Makefile so that they build. Latter required a few minor changes to alsa .tmpl files. (I did not remove all of the trailing whitespace in the .tmpl files.) Fixes kernel bugzilla #12726: http://bugzilla.kernel.org/show_bug.cgi?id=12726 Signed-off-by: Randy Dunlap Cc: documentation_man-pages@kernel-bugs.osdl.org Cc: Nicola Soranzo Signed-off-by: Takashi Iwai --- Documentation/DocBook/Makefile | 3 +- Documentation/DocBook/alsa-driver-api.tmpl | 109 + Documentation/DocBook/writing-an-alsa-driver.tmpl | 6216 ++++++++++++++++++++ .../sound/alsa/DocBook/alsa-driver-api.tmpl | 109 - .../sound/alsa/DocBook/writing-an-alsa-driver.tmpl | 6216 -------------------- 5 files changed, 6327 insertions(+), 6326 deletions(-) create mode 100644 Documentation/DocBook/alsa-driver-api.tmpl create mode 100644 Documentation/DocBook/writing-an-alsa-driver.tmpl delete mode 100644 Documentation/sound/alsa/DocBook/alsa-driver-api.tmpl delete mode 100644 Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl (limited to 'Documentation') diff --git a/Documentation/DocBook/Makefile b/Documentation/DocBook/Makefile index 1462ed86d40..a3a83d38f96 100644 --- a/Documentation/DocBook/Makefile +++ b/Documentation/DocBook/Makefile @@ -12,7 +12,8 @@ DOCBOOKS := z8530book.xml mcabook.xml device-drivers.xml \ kernel-api.xml filesystems.xml lsm.xml usb.xml kgdb.xml \ gadget.xml libata.xml mtdnand.xml librs.xml rapidio.xml \ genericirq.xml s390-drivers.xml uio-howto.xml scsi.xml \ - mac80211.xml debugobjects.xml sh.xml regulator.xml + mac80211.xml debugobjects.xml sh.xml regulator.xml \ + alsa-driver-api.xml writing-an-alsa-driver.xml ### # The build process is as follows (targets): diff --git a/Documentation/DocBook/alsa-driver-api.tmpl b/Documentation/DocBook/alsa-driver-api.tmpl new file mode 100644 index 00000000000..0230a96f056 --- /dev/null +++ b/Documentation/DocBook/alsa-driver-api.tmpl @@ -0,0 +1,109 @@ + + + + + + + + + The ALSA Driver API + + + + This document is free; you can redistribute it and/or modify it + under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + + + This document is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the + implied warranty of MERCHANTABILITY or FITNESS FOR A + PARTICULAR PURPOSE. See the GNU General Public License + for more details. + + + + You should have received a copy of the GNU General Public + License along with this program; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, + MA 02111-1307 USA + + + + + + + + Management of Cards and Devices + Card Management +!Esound/core/init.c + + Device Components +!Esound/core/device.c + + Module requests and Device File Entries +!Esound/core/sound.c + + Memory Management Helpers +!Esound/core/memory.c +!Esound/core/memalloc.c + + + PCM API + PCM Core +!Esound/core/pcm.c +!Esound/core/pcm_lib.c +!Esound/core/pcm_native.c + + PCM Format Helpers +!Esound/core/pcm_misc.c + + PCM Memory Management +!Esound/core/pcm_memory.c + + + Control/Mixer API + General Control Interface +!Esound/core/control.c + + AC97 Codec API +!Esound/pci/ac97/ac97_codec.c +!Esound/pci/ac97/ac97_pcm.c + + Virtual Master Control API +!Esound/core/vmaster.c +!Iinclude/sound/control.h + + + MIDI API + Raw MIDI API +!Esound/core/rawmidi.c + + MPU401-UART API +!Esound/drivers/mpu401/mpu401_uart.c + + + Proc Info API + Proc Info Interface +!Esound/core/info.c + + + Miscellaneous Functions + Hardware-Dependent Devices API +!Esound/core/hwdep.c + + Jack Abstraction Layer API +!Esound/core/jack.c + + ISA DMA Helpers +!Esound/core/isadma.c + + Other Helper Macros +!Iinclude/sound/core.h + + + + diff --git a/Documentation/DocBook/writing-an-alsa-driver.tmpl b/Documentation/DocBook/writing-an-alsa-driver.tmpl new file mode 100644 index 00000000000..46b08fef374 --- /dev/null +++ b/Documentation/DocBook/writing-an-alsa-driver.tmpl @@ -0,0 +1,6216 @@ + + + + + + + + + Writing an ALSA Driver + + Takashi + Iwai + +
+ tiwai@suse.de +
+ + + + Oct 15, 2007 + 0.3.7 + + + + This document describes how to write an ALSA (Advanced Linux + Sound Architecture) driver. + + + + + + Copyright (c) 2002-2005 Takashi Iwai tiwai@suse.de + + + + This document is free; you can redistribute it and/or modify it + under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + + + This document is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the + implied warranty of MERCHANTABILITY or FITNESS FOR A + PARTICULAR PURPOSE. See the GNU General Public License + for more details. + + + + You should have received a copy of the GNU General Public + License along with this program; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, + MA 02111-1307 USA + + + + + + + + + + Preface + + This document describes how to write an + + ALSA (Advanced Linux Sound Architecture) + driver. The document focuses mainly on PCI soundcards. + In the case of other device types, the API might + be different, too. However, at least the ALSA kernel API is + consistent, and therefore it would be still a bit help for + writing them. + + + + This document targets people who already have enough + C language skills and have basic linux kernel programming + knowledge. This document doesn't explain the general + topic of linux kernel coding and doesn't cover low-level + driver implementation details. It only describes + the standard way to write a PCI sound driver on ALSA. + + + + If you are already familiar with the older ALSA ver.0.5.x API, you + can check the drivers such as sound/pci/es1938.c or + sound/pci/maestro3.c which have also almost the same + code-base in the ALSA 0.5.x tree, so you can compare the differences. + + + + This document is still a draft version. Any feedback and + corrections, please!! + + + + + + + + + File Tree Structure + +
+ General + + The ALSA drivers are provided in two ways. + + + + One is the trees provided as a tarball or via cvs from the + ALSA's ftp site, and another is the 2.6 (or later) Linux kernel + tree. To synchronize both, the ALSA driver tree is split into + two different trees: alsa-kernel and alsa-driver. The former + contains purely the source code for the Linux 2.6 (or later) + tree. This tree is designed only for compilation on 2.6 or + later environment. The latter, alsa-driver, contains many subtle + files for compiling ALSA drivers outside of the Linux kernel tree, + wrapper functions for older 2.2 and 2.4 kernels, to adapt the latest kernel API, + and additional drivers which are still in development or in + tests. The drivers in alsa-driver tree will be moved to + alsa-kernel (and eventually to the 2.6 kernel tree) when they are + finished and confirmed to work fine. + + + + The file tree structure of ALSA driver is depicted below. Both + alsa-kernel and alsa-driver have almost the same file + structure, except for core directory. It's + named as acore in alsa-driver tree. + + + ALSA File Tree Structure + + sound + /core + /oss + /seq + /oss + /instr + /ioctl32 + /include + /drivers + /mpu401 + /opl3 + /i2c + /l3 + /synth + /emux + /pci + /(cards) + /isa + /(cards) + /arm + /ppc + /sparc + /usb + /pcmcia /(cards) + /oss + + + +
+ +
+ core directory + + This directory contains the middle layer which is the heart + of ALSA drivers. In this directory, the native ALSA modules are + stored. The sub-directories contain different modules and are + dependent upon the kernel config. + + +
+ core/oss + + + The codes for PCM and mixer OSS emulation modules are stored + in this directory. The rawmidi OSS emulation is included in + the ALSA rawmidi code since it's quite small. The sequencer + code is stored in core/seq/oss directory (see + + below). + +
+ +
+ core/ioctl32 + + + This directory contains the 32bit-ioctl wrappers for 64bit + architectures such like x86-64, ppc64 and sparc64. For 32bit + and alpha architectures, these are not compiled. + +
+ +
+ core/seq + + This directory and its sub-directories are for the ALSA + sequencer. This directory contains the sequencer core and + primary sequencer modules such like snd-seq-midi, + snd-seq-virmidi, etc. They are compiled only when + CONFIG_SND_SEQUENCER is set in the kernel + config. + +
+ +
+ core/seq/oss + + This contains the OSS sequencer emulation codes. + +
+ +
+ core/seq/instr + + This directory contains the modules for the sequencer + instrument layer. + +
+
+ +
+ include directory + + This is the place for the public header files of ALSA drivers, + which are to be exported to user-space, or included by + several files at different directories. Basically, the private + header files should not be placed in this directory, but you may + still find files there, due to historical reasons :) + +
+ +
+ drivers directory + + This directory contains code shared among different drivers + on different architectures. They are hence supposed not to be + architecture-specific. + For example, the dummy pcm driver and the serial MIDI + driver are found in this directory. In the sub-directories, + there is code for components which are independent from + bus and cpu architectures. + + +
+ drivers/mpu401 + + The MPU401 and MPU401-UART modules are stored here. + +
+ +
+ drivers/opl3 and opl4 + + The OPL3 and OPL4 FM-synth stuff is found here. + +
+
+ +
+ i2c directory + + This contains the ALSA i2c components. + + + + Although there is a standard i2c layer on Linux, ALSA has its + own i2c code for some cards, because the soundcard needs only a + simple operation and the standard i2c API is too complicated for + such a purpose. + + +
+ i2c/l3 + + This is a sub-directory for ARM L3 i2c. + +
+
+ +
+ synth directory + + This contains the synth middle-level modules. + + + + So far, there is only Emu8000/Emu10k1 synth driver under + the synth/emux sub-directory. + +
+ +
+ pci directory + + This directory and its sub-directories hold the top-level card modules + for PCI soundcards and the code specific to the PCI BUS. + + + + The drivers compiled from a single file are stored directly + in the pci directory, while the drivers with several source files are + stored on their own sub-directory (e.g. emu10k1, ice1712). + +
+ +
+ isa directory + + This directory and its sub-directories hold the top-level card modules + for ISA soundcards. + +
+ +
+ arm, ppc, and sparc directories + + They are used for top-level card modules which are + specific to one of these architectures. + +
+ +
+ usb directory + + This directory contains the USB-audio driver. In the latest version, the + USB MIDI driver is integrated in the usb-audio driver. + +
+ +
+ pcmcia directory + + The PCMCIA, especially PCCard drivers will go here. CardBus + drivers will be in the pci directory, because their API is identical + to that of standard PCI cards. + +
+ +
+ oss directory + + The OSS/Lite source files are stored here in Linux 2.6 (or + later) tree. In the ALSA driver tarball, this directory is empty, + of course :) + +
+ + + + + + + + Basic Flow for PCI Drivers + +
+ Outline + + The minimum flow for PCI soundcards is as follows: + + + define the PCI ID table (see the section + PCI Entries + ). + create probe() callback. + create remove() callback. + create a pci_driver structure + containing the three pointers above. + create an init() function just calling + the pci_register_driver() to register the pci_driver table + defined above. + create an exit() function to call + the pci_unregister_driver() function. + + +
+ +
+ Full Code Example + + The code example is shown below. Some parts are kept + unimplemented at this moment but will be filled in the + next sections. The numbers in the comment lines of the + snd_mychip_probe() function + refer to details explained in the following section. + + + Basic Flow for PCI Drivers - Example + + + #include + #include + #include + #include + + /* module parameters (see "Module Parameters") */ + /* SNDRV_CARDS: maximum number of cards supported by this module */ + static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX; + static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR; + static int enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE_PNP; + + /* definition of the chip-specific record */ + struct mychip { + struct snd_card *card; + /* the rest of the implementation will be in section + * "PCI Resource Management" + */ + }; + + /* chip-specific destructor + * (see "PCI Resource Management") + */ + static int snd_mychip_free(struct mychip *chip) + { + .... /* will be implemented later... */ + } + + /* component-destructor + * (see "Management of Cards and Components") + */ + static int snd_mychip_dev_free(struct snd_device *device) + { + return snd_mychip_free(device->device_data); + } + + /* chip-specific constructor + * (see "Management of Cards and Components") + */ + static int __devinit snd_mychip_create(struct snd_card *card, + struct pci_dev *pci, + struct mychip **rchip) + { + struct mychip *chip; + int err; + static struct snd_device_ops ops = { + .dev_free = snd_mychip_dev_free, + }; + + *rchip = NULL; + + /* check PCI availability here + * (see "PCI Resource Management") + */ + .... + + /* allocate a chip-specific data with zero filled */ + chip = kzalloc(sizeof(*chip), GFP_KERNEL); + if (chip == NULL) + return -ENOMEM; + + chip->card = card; + + /* rest of initialization here; will be implemented + * later, see "PCI Resource Management" + */ + .... + + err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops); + if (err < 0) { + snd_mychip_free(chip); + return err; + } + + snd_card_set_dev(card, &pci->dev); + + *rchip = chip; + return 0; + } + + /* constructor -- see "Constructor" sub-section */ + static int __devinit snd_mychip_probe(struct pci_dev *pci, + const struct pci_device_id *pci_id) + { + static int dev; + struct snd_card *card; + struct mychip *chip; + int err; + + /* (1) */ + if (dev >= SNDRV_CARDS) + return -ENODEV; + if (!enable[dev]) { + dev++; + return -ENOENT; + } + + /* (2) */ + err = snd_card_create(index[dev], id[dev], THIS_MODULE, 0, &card); + if (err < 0) + return err; + + /* (3) */ + err = snd_mychip_create(card, pci, &chip); + if (err < 0) { + snd_card_free(card); + return err; + } + + /* (4) */ + strcpy(card->driver, "My Chip"); + strcpy(card->shortname, "My Own Chip 123"); + sprintf(card->longname, "%s at 0x%lx irq %i", + card->shortname, chip->ioport, chip->irq); + + /* (5) */ + .... /* implemented later */ + + /* (6) */ + err = snd_card_register(card); + if (err < 0) { + snd_card_free(card); + return err; + } + + /* (7) */ + pci_set_drvdata(pci, card); + dev++; + return 0; + } + + /* destructor -- see the "Destructor" sub-section */ + static void __devexit snd_mychip_remove(struct pci_dev *pci) + { + snd_card_free(pci_get_drvdata(pci)); + pci_set_drvdata(pci, NULL); + } +]]> + + + +
+ +
+ Constructor + + The real constructor of PCI drivers is the probe callback. + The probe callback and other component-constructors which are called + from the probe callback should be defined with + the __devinit prefix. You + cannot use the __init prefix for them, + because any PCI device could be a hotplug device. + + + + In the probe callback, the following scheme is often used. + + +
+ 1) Check and increment the device index. + + + += SNDRV_CARDS) + return -ENODEV; + if (!enable[dev]) { + dev++; + return -ENOENT; + } +]]> + + + + where enable[dev] is the module option. + + + + Each time the probe callback is called, check the + availability of the device. If not available, simply increment + the device index and returns. dev will be incremented also + later (step + 7). + +
+ +
+ 2) Create a card instance + + + + + + + + + + The details will be explained in the section + + Management of Cards and Components. + +
+ +
+ 3) Create a main component + + In this part, the PCI resources are allocated. + + + + + + + + The details will be explained in the section PCI Resource + Management. + +
+ +
+ 4) Set the driver ID and name strings. + + + +driver, "My Chip"); + strcpy(card->shortname, "My Own Chip 123"); + sprintf(card->longname, "%s at 0x%lx irq %i", + card->shortname, chip->ioport, chip->irq); +]]> + + + + The driver field holds the minimal ID string of the + chip. This is used by alsa-lib's configurator, so keep it + simple but unique. + Even the same driver can have different driver IDs to + distinguish the functionality of each chip type. + + + + The shortname field is a string shown as more verbose + name. The longname field contains the information + shown in /proc/asound/cards. + +
+ +
+ 5) Create other components, such as mixer, MIDI, etc. + + Here you define the basic components such as + PCM, + mixer (e.g. AC97), + MIDI (e.g. MPU-401), + and other interfaces. + Also, if you want a proc + file, define it here, too. + +
+ +
+ 6) Register the card instance. + + + + + + + + + + Will be explained in the section Management + of Cards and Components, too. + +
+ +
+ 7) Set the PCI driver data and return zero. + + + + + + + + In the above, the card record is stored. This pointer is + used in the remove callback and power-management + callbacks, too. + +
+
+ +
+ Destructor + + The destructor, remove callback, simply releases the card + instance. Then the ALSA middle layer will release all the + attached components automatically. + + + + It would be typically like the following: + + + + + + + + The above code assumes that the card pointer is set to the PCI + driver data. + +
+ +
+ Header Files + + For the above example, at least the following include files + are necessary. + + + + + #include + #include + #include + #include +]]> + + + + where the last one is necessary only when module options are + defined in the source file. If the code is split into several + files, the files without module options don't need them. + + + + In addition to these headers, you'll need + <linux/interrupt.h> for interrupt + handling, and <asm/io.h> for I/O + access. If you use the mdelay() or + udelay() functions, you'll need to include + <linux/delay.h> too. + + + + The ALSA interfaces like the PCM and control APIs are defined in other + <sound/xxx.h> header files. + They have to be included after + <sound/core.h>. + + +
+ + + + + + + + Management of Cards and Components + +
+ Card Instance + + For each soundcard, a card record must be allocated. + + + + A card record is the headquarters of the soundcard. It manages + the whole list of devices (components) on the soundcard, such as + PCM, mixers, MIDI, synthesizer, and so on. Also, the card + record holds the ID and the name strings of the card, manages + the root of proc files, and controls the power-management states + and hotplug disconnections. The component list on the card + record is used to manage the correct release of resources at + destruction. + + + + As mentioned above, to create a card instance, call + snd_card_create(). + + + + + + + + + + The function takes five arguments, the card-index number, the + id string, the module pointer (usually + THIS_MODULE), + the size of extra-data space, and the pointer to return the + card instance. The extra_size argument is used to + allocate card->private_data for the + chip-specific data. Note that these data + are allocated by snd_card_create(). + +
+ +
+ Components + + After the card is created, you can attach the components + (devices) to the card instance. In an ALSA driver, a component is + represented as a struct snd_device object. + A component can be a PCM instance, a control interface, a raw + MIDI interface, etc. Each such instance has one component + entry. + + + + A component can be created via + snd_device_new() function. + + + + + + + + + + This takes the card pointer, the device-level + (SNDRV_DEV_XXX), the data pointer, and the + callback pointers (&ops). The + device-level defines the type of components and the order of + registration and de-registration. For most components, the + device-level is already defined. For a user-defined component, + you can use SNDRV_DEV_LOWLEVEL. + + + + This function itself doesn't allocate the data space. The data + must be allocated manually beforehand, and its pointer is passed + as the argument. This pointer is used as the + (chip identifier in the above example) + for the instance. + + + + Each pre-defined ALSA component such as ac97 and pcm calls + snd_device_new() inside its + constructor. The destructor for each component is defined in the + callback pointers. Hence, you don't need to take care of + calling a destructor for such a component. + + + + If you wish to create your own component, you need to + set the destructor function to the dev_free callback in + the ops, so that it can be released + automatically via snd_card_free(). + The next example will show an implementation of chip-specific + data. + +
+ +
+ Chip-Specific Data + + Chip-specific information, e.g. the I/O port address, its + resource pointer, or the irq number, is stored in the + chip-specific record. + + + + + + + + + + In general, there are two ways of allocating the chip record. + + +
+ 1. Allocating via <function>snd_card_create()</function>. + + As mentioned above, you can pass the extra-data-length + to the 4th argument of snd_card_create(), i.e. + + + + + + + + struct mychip is the type of the chip record. + + + + In return, the allocated record can be accessed as + + + +private_data; +]]> + + + + With this method, you don't have to allocate twice. + The record is released together with the card instance. + +
+ +
+ 2. Allocating an extra device. + + + After allocating a card instance via + snd_card_create() (with + 0 on the 4th arg), call + kzalloc(). + + + + + + + + + + The chip record should have the field to hold the card + pointer at least, + + + + + + + + + + Then, set the card pointer in the returned chip instance. + + + +card = card; +]]> + + + + + + Next, initialize the fields, and register this chip + record as a low-level device with a specified + ops, + + + + + + + + snd_mychip_dev_free() is the + device-destructor function, which will call the real + destructor. + + + + + +device_data); + } +]]> + + + + where snd_mychip_free() is the real destructor. + +
+
+ +
+ Registration and Release + + After all components are assigned, register the card instance + by calling snd_card_register(). Access + to the device files is enabled at this point. That is, before + snd_card_register() is called, the + components are safely inaccessible from external side. If this + call fails, exit the probe function after releasing the card via + snd_card_free(). + + + + For releasing the card instance, you can call simply + snd_card_free(). As mentioned earlier, all + components are released automatically by this call. + + + + As further notes, the destructors (both + snd_mychip_dev_free and + snd_mychip_free) cannot be defined with + the __devexit prefix, because they may be + called from the constructor, too, at the false path. + + + + For a device which allows hotplugging, you can use + snd_card_free_when_closed. This one will + postpone the destruction until all devices are closed. + + +
+ + + + + + + + + PCI Resource Management + +
+ Full Code Example + + In this section, we'll complete the chip-specific constructor, + destructor and PCI entries. Example code is shown first, + below. + + + PCI Resource Management Example + +irq >= 0) + free_irq(chip->irq, chip); + /* release the I/O ports & memory */ + pci_release_regions(chip->pci); + /* disable the PCI entry */ + pci_disable_device(chip->pci); + /* release the data */ + kfree(chip); + return 0; + } + + /* chip-specific constructor */ + static int __devinit snd_mychip_create(struct snd_card *card, + struct pci_dev *pci, + struct mychip **rchip) + { + struct mychip *chip; + int err; + static struct snd_device_ops ops = { + .dev_free = snd_mychip_dev_free, + }; + + *rchip = NULL; + + /* initialize the PCI entry */ + err = pci_enable_device(pci); + if (err < 0) + return err; + /* check PCI availability (28bit DMA) */ + if (pci_set_dma_mask(pci, DMA_28BIT_MASK) < 0 || + pci_set_consistent_dma_mask(pci, DMA_28BIT_MASK) < 0) { + printk(KERN_ERR "error to set 28bit mask DMA\n"); + pci_disable_device(pci); + return -ENXIO; + } + + chip = kzalloc(sizeof(*chip), GFP_KERNEL); + if (chip == NULL) { + pci_disable_device(pci); + return -ENOMEM; + } + + /* initialize the stuff */ + chip->card = card; + chip->pci = pci; + chip->irq = -1; + + /* (1) PCI resource allocation */ + err = pci_request_regions(pci, "My Chip"); + if (err < 0) { + kfree(chip); + pci_disable_device(pci); + return err; + } + chip->port = pci_resource_start(pci, 0); + if (request_irq(pci->irq, snd_mychip_interrupt, + IRQF_SHARED, "My Chip", chip)) { + printk(KERN_ERR "cannot grab irq %d\n", pci->irq); + snd_mychip_free(chip); + return -EBUSY; + } + chip->irq = pci->irq; + + /* (2) initialization of the chip hardware */ + .... /* (not implemented in this document) */ + + err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops); + if (err < 0) { + snd_mychip_free(chip); + return err; + } + + snd_card_set_dev(card, &pci->dev); + + *rchip = chip; + return 0; + } + + /* PCI IDs */ + static struct pci_device_id snd_mychip_ids[] = { + { PCI_VENDOR_ID_FOO, PCI_DEVICE_ID_BAR, + PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, + .... + { 0, } + }; + MODULE_DEVICE_TABLE(pci, snd_mychip_ids); + + /* pci_driver definition */ + static struct pci_driver driver = { + .name = "My Own Chip", + .id_table = snd_mychip_ids, + .probe = snd_mychip_probe, + .remove = __devexit_p(snd_mychip_remove), + }; + + /* module initialization */ + static int __init alsa_card_mychip_init(void) + { + return pci_register_driver(&driver); + } + + /* module clean up */ + static void __exit alsa_card_mychip_exit(void) + { + pci_unregister_driver(&driver); + } + + module_init(alsa_card_mychip_init) + module_exit(alsa_card_mychip_exit) + + EXPORT_NO_SYMBOLS; /* for old kernels only */ +]]> + + + +
+ +
+ Some Hafta's + + The allocation of PCI resources is done in the + probe() function, and usually an extra + xxx_create() function is written for this + purpose. + + + + In the case of PCI devices, you first have to call + the pci_enable_device() function before + allocating resources. Also, you need to set the proper PCI DMA + mask to limit the accessed I/O range. In some cases, you might + need to call pci_set_master() function, + too. + + + + Suppose the 28bit mask, and the code to be added would be like: + + + + + + + +
+ +
+ Resource Allocation + + The allocation of I/O ports and irqs is done via standard kernel + functions. Unlike ALSA ver.0.5.x., there are no helpers for + that. And these resources must be released in the destructor + function (see below). Also, on ALSA 0.9.x, you don't need to + allocate (pseudo-)DMA for PCI like in ALSA 0.5.x. + + + + Now assume that the PCI device has an I/O port with 8 bytes + and an interrupt. Then struct mychip will have the + following fields: + + + + + + + + + + For an I/O port (and also a memory region), you need to have + the resource pointer for the standard resource management. For + an irq, you have to keep only the irq number (integer). But you + need to initialize this number as -1 before actual allocation, + since irq 0 is valid. The port address and its resource pointer + can be initialized as null by + kzalloc() automatically, so you + don't have to take care of resetting them. + + + + The allocation of an I/O port is done like this: + + + +port = pci_resource_start(pci, 0); +]]> + + + + + + + It will reserve the I/O port region of 8 bytes of the given + PCI device. The returned value, chip->res_port, is allocated + via kmalloc() by + request_region(). The pointer must be + released via kfree(), but there is a + problem with this. This issue will be explained later. + + + + The allocation of an interrupt source is done like this: + + + +irq, snd_mychip_interrupt, + IRQF_SHARED, "My Chip", chip)) { + printk(KERN_ERR "cannot grab irq %d\n", pci->irq); + snd_mychip_free(chip); + return -EBUSY; + } + chip->irq = pci->irq; +]]> + + + + where snd_mychip_interrupt() is the + interrupt handler defined later. + Note that chip->irq should be defined + only when request_irq() succeeded. + + + + On the PCI bus, interrupts can be shared. Thus, + IRQF_SHARED is used as the interrupt flag of + request_irq(). + + + + The last argument of request_irq() is the + data pointer passed to the interrupt handler. Usually, the + chip-specific record is used for that, but you can use what you + like, too. + + + + I won't give details about the interrupt handler at this + point, but at least its appearance can be explained now. The + interrupt handler looks usually like the following: + + + + + + + + + + Now let's write the corresponding destructor for the resources + above. The role of destructor is simple: disable the hardware + (if already activated) and release the resources. So far, we + have no hardware part, so the disabling code is not written here. + + + + To release the resources, the check-and-release + method is a safer way. For the interrupt, do like this: + + + +irq >= 0) + free_irq(chip->irq, chip); +]]> + + + + Since the irq number can start from 0, you should initialize + chip->irq with a negative value (e.g. -1), so that you can + check the validity of the irq number as above. + + + + When you requested I/O ports or memory regions via + pci_request_region() or + pci_request_regions() like in this example, + release the resource(s) using the corresponding function, + pci_release_region() or + pci_release_regions(). + + + +pci); +]]> + + + + + + When you requested manually via request_region() + or request_mem_region, you can release it via + release_resource(). Suppose that you keep + the resource pointer returned from request_region() + in chip->res_port, the release procedure looks like: + + + +res_port); +]]> + + + + + + Don't forget to call pci_disable_device() + before the end. + + + + And finally, release the chip-specific record. + + + + + + + + + + Again, remember that you cannot + use the __devexit prefix for this destructor. + + + + We didn't implement the hardware disabling part in the above. + If you need to do this, please note that the destructor may be + called even before the initialization of the chip is completed. + It would be better to have a flag to skip hardware disabling + if the hardware was not initialized yet. + + + + When the chip-data is assigned to the card using + snd_device_new() with + SNDRV_DEV_LOWLELVEL , its destructor is + called at the last. That is, it is assured that all other + components like PCMs and controls have already been released. + You don't have to stop PCMs, etc. explicitly, but just + call low-level hardware stopping. + + + + The management of a memory-mapped region is almost as same as + the management of an I/O port. You'll need three fields like + the following: + + + + + + + + and the allocation would be like below: + + + +iobase_phys = pci_resource_start(pci, 0); + chip->iobase_virt = ioremap_nocache(chip->iobase_phys, + pci_resource_len(pci, 0)); +]]> + + + + and the corresponding destructor would be: + + + +iobase_virt) + iounmap(chip->iobase_virt); + .... + pci_release_regions(chip->pci); + .... + } +]]> + + + + +
+ +
+ Registration of Device Struct + + At some point, typically after calling snd_device_new(), + you need to register the struct device of the chip + you're handling for udev and co. ALSA provides a macro for compatibility with + older kernels. Simply call like the following: + + +dev); +]]> + + + so that it stores the PCI's device pointer to the card. This will be + referred by ALSA core functions later when the devices are registered. + + + In the case of non-PCI, pass the proper device struct pointer of the BUS + instead. (In the case of legacy ISA without PnP, you don't have to do + anything.) + +
+ +
+ PCI Entries + + So far, so good. Let's finish the missing PCI + stuff. At first, we need a + pci_device_id table for this + chipset. It's a table of PCI vendor/device ID number, and some + masks. + + + + For example, + + + + + + + + + + The first and second fields of + the pci_device_id structure are the vendor and + device IDs. If you have no reason to filter the matching + devices, you can leave the remaining fields as above. The last + field of the pci_device_id struct contains + private data for this entry. You can specify any value here, for + example, to define specific operations for supported device IDs. + Such an example is found in the intel8x0 driver. + + + + The last entry of this list is the terminator. You must + specify this all-zero entry. + + + + Then, prepare the pci_driver record: + + + + + + + + + + The probe and + remove functions have already + been defined in the previous sections. + The remove function should + be defined with the + __devexit_p() macro, so that it's not + defined for built-in (and non-hot-pluggable) case. The + name + field is the name string of this device. Note that you must not + use a slash / in this string. + + + + And at last, the module entries: + + + + + + + + + + Note that these module entries are tagged with + __init and + __exit prefixes, not + __devinit nor + __devexit. + + + + Oh, one thing was forgotten. If you have no exported symbols, + you need to declare it in 2.2 or 2.4 kernels (it's not necessary in 2.6 kernels). + + + + + + + + That's all! + +
+ + + + + + + + PCM Interface + +
+ General + + The PCM middle layer of ALSA is quite powerful and it is only + necessary for each driver to implement the low-level functions + to access its hardware. + + + + For accessing to the PCM layer, you need to include + <sound/pcm.h> first. In addition, + <sound/pcm_params.h> might be needed + if you access to some functions related with hw_param. + + + + Each card device can have up to four pcm instances. A pcm + instance corresponds to a pcm device file. The limitation of + number of instances comes only from the available bit size of + the Linux's device numbers. Once when 64bit device number is + used, we'll have more pcm instances available. + + + + A pcm instance consists of pcm playback and capture streams, + and each pcm stream consists of one or more pcm substreams. Some + soundcards support multiple playback functions. For example, + emu10k1 has a PCM playback of 32 stereo substreams. In this case, at + each open, a free substream is (usually) automatically chosen + and opened. Meanwhile, when only one substream exists and it was + already opened, the successful open will either block + or error with EAGAIN according to the + file open mode. But you don't have to care about such details in your + driver. The PCM middle layer will take care of such work. + +
+ +
+ Full Code Example + + The example code below does not include any hardware access + routines but shows only the skeleton, how to build up the PCM + interfaces. + + + PCM Example Code + + + .... + + /* hardware definition */ + static struct snd_pcm_hardware snd_mychip_playback_hw = { + .info = (SNDRV_PCM_INFO_MMAP | + SNDRV_PCM_INFO_INTERLEAVED | + SNDRV_PCM_INFO_BLOCK_TRANSFER | + SNDRV_PCM_INFO_MMAP_VALID), + .formats = SNDRV_PCM_FMTBIT_S16_LE, + .rates = SNDRV_PCM_RATE_8000_48000, + .rate_min = 8000, + .rate_max = 48000, + .channels_min = 2, + .channels_max = 2, + .buffer_bytes_max = 32768, + .period_bytes_min = 4096, + .period_bytes_max = 32768, + .periods_min = 1, + .periods_max = 1024, + }; + + /* hardware definition */ + static struct snd_pcm_hardware snd_mychip_capture_hw = { + .info = (SNDRV_PCM_INFO_MMAP | + SNDRV_PCM_INFO_INTERLEAVED | + SNDRV_PCM_INFO_BLOCK_TRANSFER | + SNDRV_PCM_INFO_MMAP_VALID), + .formats = SNDRV_PCM_FMTBIT_S16_LE, + .rates = SNDRV_PCM_RATE_8000_48000, + .rate_min = 8000, + .rate_max = 48000, + .channels_min = 2, + .channels_max = 2, + .buffer_bytes_max = 32768, + .period_bytes_min = 4096, + .period_bytes_max = 32768, + .periods_min = 1, + .periods_max = 1024, + }; + + /* open callback */ + static int snd_mychip_playback_open(struct snd_pcm_substream *substream) + { + struct mychip *chip = snd_pcm_substream_chip(substream); + struct snd_pcm_runtime *runtime = substream->runtime; + + runtime->hw = snd_mychip_playback_hw; + /* more hardware-initialization will be done here */ + .... + return 0; + } + + /* close callback */ + static int snd_mychip_playback_close(struct snd_pcm_substream *substream) + { + struct mychip *chip = snd_pcm_substream_chip(substream); + /* the hardware-specific codes will be here */ + .... + return 0; + + } + + /* open callback */ + static int snd_mychip_capture_open(struct snd_pcm_substream *substream) + { + struct mychip *chip = snd_pcm_substream_chip(substream); + struct snd_pcm_runtime *runtime = substream->runtime; + + runtime->hw = snd_mychip_capture_hw; + /* more hardware-initialization will be done here */ + .... + return 0; + } + + /* close callback */ + static int snd_mychip_capture_close(struct snd_pcm_substream *substream) + { + struct mychip *chip = snd_pcm_substream_chip(substream); + /* the hardware-specific codes will be here */ + .... + return 0; + + } + + /* hw_params callback */ + static int snd_mychip_pcm_hw_params(struct snd_pcm_substream *substream, + struct snd_pcm_hw_params *hw_params) + { + return snd_pcm_lib_malloc_pages(substream, + params_buffer_bytes(hw_params)); + } + + /* hw_free callback */ + static int snd_mychip_pcm_hw_free(struct snd_pcm_substream *substream) + { + return snd_pcm_lib_free_pages(substream); + } + + /* prepare callback */ + static int snd_mychip_pcm_prepare(struct snd_pcm_substream *substream) + { + struct mychip *chip = snd_pcm_substream_chip(substream); + struct snd_pcm_runtime *runtime = substream->runtime; + + /* set up the hardware with the current configuration + * for example... + */ + mychip_set_sample_format(chip, runtime->format); + mychip_set_sample_rate(chip, runtime->rate); + mychip_set_channels(chip, runtime->channels); + mychip_set_dma_setup(chip, runtime->dma_addr, + chip->buffer_size, + chip->period_size); + return 0; + } + + /* trigger callback */ + static int snd_mychip_pcm_trigger(struct snd_pcm_substream *substream, + int cmd) + { + switch (cmd) { + case SNDRV_PCM_TRIGGER_START: + /* do something to start the PCM engine */ + .... + break; + case SNDRV_PCM_TRIGGER_STOP: + /* do something to stop the PCM engine */ + .... + break; + default: + return -EINVAL; + } + } + + /* pointer callback */ + static snd_pcm_uframes_t + snd_mychip_pcm_pointer(struct snd_pcm_substream *substream) + { + struct mychip *chip = snd_pcm_substream_chip(substream); + unsigned int current_ptr; + + /* get the current hardware pointer */ + current_ptr = mychip_get_hw_pointer(chip); + return current_ptr; + } + + /* operators */ + static struct snd_pcm_ops snd_mychip_playback_ops = { + .open = snd_mychip_playback_open, + .close = snd_mychip_playback_close, + .ioctl = snd_pcm_lib_ioctl, + .hw_params = snd_mychip_pcm_hw_params, + .hw_free = snd_mychip_pcm_hw_free, + .prepare = snd_mychip_pcm_prepare, + .trigger = snd_mychip_pcm_trigger, + .pointer = snd_mychip_pcm_pointer, + }; + + /* operators */ + static struct snd_pcm_ops snd_mychip_capture_ops = { + .open = snd_mychip_capture_open, + .close = snd_mychip_capture_close, + .ioctl = snd_pcm_lib_ioctl, + .hw_params = snd_mychip_pcm_hw_params, + .hw_free = snd_mychip_pcm_hw_free, + .prepare = snd_mychip_pcm_prepare, + .trigger = snd_mychip_pcm_trigger, + .pointer = snd_mychip_pcm_pointer, + }; + + /* + * definitions of capture are omitted here... + */ + + /* create a pcm device */ + static int __devinit snd_mychip_new_pcm(struct mychip *chip) + { + struct snd_pcm *pcm; + int err; + + err = snd_pcm_new(chip->card, "My Chip", 0, 1, 1, &pcm); + if (err < 0) + return err; + pcm->private_data = chip; + strcpy(pcm->name, "My Chip"); + chip->pcm = pcm; + /* set operators */ + snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, + &snd_mychip_playback_ops); + snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, + &snd_mychip_capture_ops); + /* pre-allocation of buffers */ + /* NOTE: this may fail */ + snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV, + snd_dma_pci_data(chip->pci), + 64*1024, 64*1024); + return 0; + } +]]> + + + +
+ +
+ Constructor + + A pcm instance is allocated by the snd_pcm_new() + function. It would be better to create a constructor for pcm, + namely, + + + +card, "My Chip", 0, 1, 1, &pcm); + if (err < 0) + return err; + pcm->private_data = chip; + strcpy(pcm->name, "My Chip"); + chip->pcm = pcm; + .... + return 0; + } +]]> + + + + + + The snd_pcm_new() function takes four + arguments. The first argument is the card pointer to which this + pcm is assigned, and the second is the ID string. + + + + The third argument (index, 0 in the + above) is the index of this new pcm. It begins from zero. If + you create more than one pcm instances, specify the + different numbers in this argument. For example, + index = 1 for the second PCM device. + + + + The fourth and fifth arguments are the number of substreams + for playback and capture, respectively. Here 1 is used for + both arguments. When no playback or capture substreams are available, + pass 0 to the corresponding argument. + + + + If a chip supports multiple playbacks or captures, you can + specify more numbers, but they must be handled properly in + open/close, etc. callbacks. When you need to know which + substream you are referring to, then it can be obtained from + struct snd_pcm_substream data passed to each callback + as follows: + + + +number; +]]> + + + + + + After the pcm is created, you need to set operators for each + pcm stream. + + + + + + + + + + The operators are defined typically like this: + + + + + + + + All the callbacks are described in the + + Operators subsection. + + + + After setting the operators, you probably will want to + pre-allocate the buffer. For the pre-allocation, simply call + the following: + + + +pci), + 64*1024, 64*1024); +]]> + + + + It will allocate a buffer up to 64kB as default. + Buffer management details will be described in the later section Buffer and Memory + Management. + + + + Additionally, you can set some extra information for this pcm + in pcm->info_flags. + The available values are defined as + SNDRV_PCM_INFO_XXX in + <sound/asound.h>, which is used for + the hardware definition (described later). When your soundchip + supports only half-duplex, specify like this: + + + +info_flags = SNDRV_PCM_INFO_HALF_DUPLEX; +]]> + + + +
+ +
+ ... And the Destructor? + + The destructor for a pcm instance is not always + necessary. Since the pcm device will be released by the middle + layer code automatically, you don't have to call the destructor + explicitly. + + + + The destructor would be necessary if you created + special records internally and needed to release them. In such a + case, set the destructor function to + pcm->private_free: + + + PCM Instance with a Destructor + +my_private_pcm_data); + /* do what you like else */ + .... + } + + static int __devinit snd_mychip_new_pcm(struct mychip *chip) + { + struct snd_pcm *pcm; + .... + /* allocate your own data */ + chip->my_private_pcm_data = kmalloc(...); + /* set the destructor */ + pcm->private_data = chip; + pcm->private_free = mychip_pcm_free; + .... + } +]]> + + + +
+ +
+ Runtime Pointer - The Chest of PCM Information + + When the PCM substream is opened, a PCM runtime instance is + allocated and assigned to the substream. This pointer is + accessible via substream->runtime. + This runtime pointer holds most information you need + to control the PCM: the copy of hw_params and sw_params configurations, the buffer + pointers, mmap records, spinlocks, etc. + + + + The definition of runtime instance is found in + <sound/pcm.h>. Here are + the contents of this file: + + + + + + + + + For the operators (callbacks) of each sound driver, most of + these records are supposed to be read-only. Only the PCM + middle-layer changes / updates them. The exceptions are + the hardware description (hw), interrupt callbacks + (transfer_ack_xxx), DMA buffer information, and the private + data. Besides, if you use the standard buffer allocation + method via snd_pcm_lib_malloc_pages(), + you don't need to set the DMA buffer information by yourself. + + + + In the sections below, important records are explained. + + +
+ Hardware Description + + The hardware descriptor (struct snd_pcm_hardware) + contains the definitions of the fundamental hardware + configuration. Above all, you'll need to define this in + + the open callback. + Note that the runtime instance holds the copy of the + descriptor, not the pointer to the existing descriptor. That + is, in the open callback, you can modify the copied descriptor + (runtime->hw) as you need. For example, if the maximum + number of channels is 1 only on some chip models, you can + still use the same hardware descriptor and change the + channels_max later: + + +runtime; + ... + runtime->hw = snd_mychip_playback_hw; /* common definition */ + if (chip->model == VERY_OLD_ONE) + runtime->hw.channels_max = 1; +]]> + + + + + + Typically, you'll have a hardware descriptor as below: + + + + + + + + + + + The info field contains the type and + capabilities of this pcm. The bit flags are defined in + <sound/asound.h> as + SNDRV_PCM_INFO_XXX. Here, at least, you + have to specify whether the mmap is supported and which + interleaved format is supported. + When the is supported, add the + SNDRV_PCM_INFO_MMAP flag here. When the + hardware supports the interleaved or the non-interleaved + formats, SNDRV_PCM_INFO_INTERLEAVED or + SNDRV_PCM_INFO_NONINTERLEAVED flag must + be set, respectively. If both are supported, you can set both, + too. + + + + In the above example, MMAP_VALID and + BLOCK_TRANSFER are specified for the OSS mmap + mode. Usually both are set. Of course, + MMAP_VALID is set only if the mmap is + really supported. + + + + The other possible flags are + SNDRV_PCM_INFO_PAUSE and + SNDRV_PCM_INFO_RESUME. The + PAUSE bit means that the pcm supports the + pause operation, while the + RESUME bit means that the pcm supports + the full suspend/resume operation. + If the PAUSE flag is set, + the trigger callback below + must handle the corresponding (pause push/release) commands. + The suspend/resume trigger commands can be defined even without + the RESUME flag. See + Power Management section for details. + + + + When the PCM substreams can be synchronized (typically, + synchronized start/stop of a playback and a capture streams), + you can give SNDRV_PCM_INFO_SYNC_START, + too. In this case, you'll need to check the linked-list of + PCM substreams in the trigger callback. This will be + described in the later section. + + + + + + formats field contains the bit-flags + of supported formats (SNDRV_PCM_FMTBIT_XXX). + If the hardware supports more than one format, give all or'ed + bits. In the example above, the signed 16bit little-endian + format is specified. + + + + + + rates field contains the bit-flags of + supported rates (SNDRV_PCM_RATE_XXX). + When the chip supports continuous rates, pass + CONTINUOUS bit additionally. + The pre-defined rate bits are provided only for typical + rates. If your chip supports unconventional rates, you need to add + the KNOT bit and set up the hardware + constraint manually (explained later). + + + + + + rate_min and + rate_max define the minimum and + maximum sample rate. This should correspond somehow to + rates bits. + + + + + + channel_min and + channel_max + define, as you might already expected, the minimum and maximum + number of channels. + + + + + + buffer_bytes_max defines the + maximum buffer size in bytes. There is no + buffer_bytes_min field, since + it can be calculated from the minimum period size and the + minimum number of periods. + Meanwhile, period_bytes_min and + define the minimum and maximum size of the period in bytes. + periods_max and + periods_min define the maximum and + minimum number of periods in the buffer. + + + + The period is a term that corresponds to + a fragment in the OSS world. The period defines the size at + which a PCM interrupt is generated. This size strongly + depends on the hardware. + Generally, the smaller period size will give you more + interrupts, that is, more controls. + In the case of capture, this size defines the input latency. + On the other hand, the whole buffer size defines the + output latency for the playback direction. + + + + + + There is also a field fifo_size. + This specifies the size of the hardware FIFO, but currently it + is neither used in the driver nor in the alsa-lib. So, you + can ignore this field. + + + + +
+ +
+ PCM Configurations + + Ok, let's go back again to the PCM runtime records. + The most frequently referred records in the runtime instance are + the PCM configurations. + The PCM configurations are stored in the runtime instance + after the application sends hw_params data via + alsa-lib. There are many fields copied from hw_params and + sw_params structs. For example, + format holds the format type + chosen by the application. This field contains the enum value + SNDRV_PCM_FORMAT_XXX. + + + + One thing to be noted is that the configured buffer and period + sizes are stored in frames in the runtime. + In the ALSA world, 1 frame = channels * samples-size. + For conversion between frames and bytes, you can use the + frames_to_bytes() and + bytes_to_frames() helper functions. + + +period_size); +]]> + + + + + + Also, many software parameters (sw_params) are + stored in frames, too. Please check the type of the field. + snd_pcm_uframes_t is for the frames as unsigned + integer while snd_pcm_sframes_t is for the frames + as signed integer. + +
+ +
+ DMA Buffer Information + + The DMA buffer is defined by the following four fields, + dma_area, + dma_addr, + dma_bytes and + dma_private. + The dma_area holds the buffer + pointer (the logical address). You can call + memcpy from/to + this pointer. Meanwhile, dma_addr + holds the physical address of the buffer. This field is + specified only when the buffer is a linear buffer. + dma_bytes holds the size of buffer + in bytes. dma_private is used for + the ALSA DMA allocator. + + + + If you use a standard ALSA function, + snd_pcm_lib_malloc_pages(), for + allocating the buffer, these fields are set by the ALSA middle + layer, and you should not change them by + yourself. You can read them but not write them. + On the other hand, if you want to allocate the buffer by + yourself, you'll need to manage it in hw_params callback. + At least, dma_bytes is mandatory. + dma_area is necessary when the + buffer is mmapped. If your driver doesn't support mmap, this + field is not necessary. dma_addr + is also optional. You can use + dma_private as you like, too. + +
+ +
+ Running Status + + The running status can be referred via runtime->status. + This is the pointer to the struct snd_pcm_mmap_status + record. For example, you can get the current DMA hardware + pointer via runtime->status->hw_ptr. + + + + The DMA application pointer can be referred via + runtime->control, which points to the + struct snd_pcm_mmap_control record. + However, accessing directly to this value is not recommended. + +
+ +
+ Private Data + + You can allocate a record for the substream and store it in + runtime->private_data. Usually, this + is done in + + the open callback. + Don't mix this with pcm->private_data. + The pcm->private_data usually points to the + chip instance assigned statically at the creation of PCM, while the + runtime->private_data points to a dynamic + data structure created at the PCM open callback. + + + +runtime->private_data = data; + .... + } +]]> + + + + + + The allocated object must be released in + + the close callback. + +
+ +
+ Interrupt Callbacks + + The field transfer_ack_begin and + transfer_ack_end are called at + the beginning and at the end of + snd_pcm_period_elapsed(), respectively. + +
+ +
+ +
+ Operators + + OK, now let me give details about each pcm callback + (ops). In general, every callback must + return 0 if successful, or a negative error number + such as -EINVAL. To choose an appropriate + error number, it is advised to check what value other parts of + the kernel return when the same kind of request fails. + + + + The callback function takes at least the argument with + snd_pcm_substream pointer. To retrieve + the chip record from the given substream instance, you can use the + following macro. + + + + + + + + The macro reads substream->private_data, + which is a copy of pcm->private_data. + You can override the former if you need to assign different data + records per PCM substream. For example, the cmi8330 driver assigns + different private_data for playback and capture directions, + because it uses two different codecs (SB- and AD-compatible) for + different directions. + + +
+ open callback + + + + + + + + This is called when a pcm substream is opened. + + + + At least, here you have to initialize the runtime->hw + record. Typically, this is done by like this: + + + +runtime; + + runtime->hw = snd_mychip_playback_hw; + return 0; + } +]]> + + + + where snd_mychip_playback_hw is the + pre-defined hardware description. + + + + You can allocate a private data in this callback, as described + in + Private Data section. + + + + If the hardware configuration needs more constraints, set the + hardware constraints here, too. + See + Constraints for more details. + +
+ +
+ close callback + + + + + + + + Obviously, this is called when a pcm substream is closed. + + + + Any private instance for a pcm substream allocated in the + open callback will be released here. + + + +runtime->private_data); + .... + } +]]> + + + +
+ +
+ ioctl callback + + This is used for any special call to pcm ioctls. But + usually you can pass a generic ioctl callback, + snd_pcm_lib_ioctl. + +
+ +
+ hw_params callback + + + + + + + + + + This is called when the hardware parameter + (hw_params) is set + up by the application, + that is, once when the buffer size, the period size, the + format, etc. are defined for the pcm substream. + + + + Many hardware setups should be done in this callback, + including the allocation of buffers. + + + + Parameters to be initialized are retrieved by + params_xxx() macros. To allocate + buffer, you can call a helper function, + + + + + + + + snd_pcm_lib_malloc_pages() is available + only when the DMA buffers have been pre-allocated. + See the section + Buffer Types for more details. + + + + Note that this and prepare callbacks + may be called multiple times per initialization. + For example, the OSS emulation may + call these callbacks at each change via its ioctl. + + + + Thus, you need to be careful not to allocate the same buffers + many times, which will lead to memory leaks! Calling the + helper function above many times is OK. It will release the + previous buffer automatically when it was already allocated. + + + + Another note is that this callback is non-atomic + (schedulable). This is important, because the + trigger callback + is atomic (non-schedulable). That is, mutexes or any + schedule-related functions are not available in + trigger callback. + Please see the subsection + + Atomicity for details. + +
+ +
+ hw_free callback + + + + + + + + + + This is called to release the resources allocated via + hw_params. For example, releasing the + buffer via + snd_pcm_lib_malloc_pages() is done by + calling the following: + + + + + + + + + + This function is always called before the close callback is called. + Also, the callback may be called multiple times, too. + Keep track whether the resource was already released. + +
+ +
+ prepare callback + + + + + + + + + + This callback is called when the pcm is + prepared. You can set the format type, sample + rate, etc. here. The difference from + hw_params is that the + prepare callback will be called each + time + snd_pcm_prepare() is called, i.e. when + recovering after underruns, etc. + + + + Note that this callback is now non-atomic. + You can use schedule-related functions safely in this callback. + + + + In this and the following callbacks, you can refer to the + values via the runtime record, + substream->runtime. + For example, to get the current + rate, format or channels, access to + runtime->rate, + runtime->format or + runtime->channels, respectively. + The physical address of the allocated buffer is set to + runtime->dma_area. The buffer and period sizes are + in runtime->buffer_size and runtime->period_size, + respectively. + + + + Be careful that this callback will be called many times at + each setup, too. + +
+ +
+ trigger callback + + + + + + + + This is called when the pcm is started, stopped or paused. + + + + Which action is specified in the second argument, + SNDRV_PCM_TRIGGER_XXX in + <sound/pcm.h>. At least, + the START and STOP + commands must be defined in this callback. + + + + + + + + + + When the pcm supports the pause operation (given in the info + field of the hardware table), the PAUSE_PUSE + and PAUSE_RELEASE commands must be + handled here, too. The former is the command to pause the pcm, + and the latter to restart the pcm again. + + + + When the pcm supports the suspend/resume operation, + regardless of full or partial suspend/resume support, + the SUSPEND and RESUME + commands must be handled, too. + These commands are issued when the power-management status is + changed. Obviously, the SUSPEND and + RESUME commands + suspend and resume the pcm substream, and usually, they + are identical to the STOP and + START commands, respectively. + See the + Power Management section for details. + + + + As mentioned, this callback is atomic. You cannot call + functions which may sleep. + The trigger callback should be as minimal as possible, + just really triggering the DMA. The other stuff should be + initialized hw_params and prepare callbacks properly + beforehand. + +
+ +
+ pointer callback + + + + + + + + This callback is called when the PCM middle layer inquires + the current hardware position on the buffer. The position must + be returned in frames, + ranging from 0 to buffer_size - 1. + + + + This is called usually from the buffer-update routine in the + pcm middle layer, which is invoked when + snd_pcm_period_elapsed() is called in the + interrupt routine. Then the pcm middle layer updates the + position and calculates the available space, and wakes up the + sleeping poll threads, etc. + + + + This callback is also atomic. + +
+ +
+ copy and silence callbacks + + These callbacks are not mandatory, and can be omitted in + most cases. These callbacks are used when the hardware buffer + cannot be in the normal memory space. Some chips have their + own buffer on the hardware which is not mappable. In such a + case, you have to transfer the data manually from the memory + buffer to the hardware buffer. Or, if the buffer is + non-contiguous on both physical and virtual memory spaces, + these callbacks must be defined, too. + + + + If these two callbacks are defined, copy and set-silence + operations are done by them. The detailed will be described in + the later section Buffer and Memory + Management. + +
+ +
+ ack callback + + This callback is also not mandatory. This callback is called + when the appl_ptr is updated in read or write operations. + Some drivers like emu10k1-fx and cs46xx need to track the + current appl_ptr for the internal buffer, and this callback + is useful only for such a purpose. + + + This callback is atomic. + +
+ +
+ page callback + + + This callback is optional too. This callback is used + mainly for non-contiguous buffers. The mmap calls this + callback to get the page address. Some examples will be + explained in the later section Buffer and Memory + Management, too. + +
+
+ +
+ Interrupt Handler + + The rest of pcm stuff is the PCM interrupt handler. The + role of PCM interrupt handler in the sound driver is to update + the buffer position and to tell the PCM middle layer when the + buffer position goes across the prescribed period size. To + inform this, call the snd_pcm_period_elapsed() + function. + + + + There are several types of sound chips to generate the interrupts. + + +
+ Interrupts at the period (fragment) boundary + + This is the most frequently found type: the hardware + generates an interrupt at each period boundary. + In this case, you can call + snd_pcm_period_elapsed() at each + interrupt. + + + + snd_pcm_period_elapsed() takes the + substream pointer as its argument. Thus, you need to keep the + substream pointer accessible from the chip instance. For + example, define substream field in the chip record to hold the + current running substream pointer, and set the pointer value + at open callback (and reset at close callback). + + + + If you acquire a spinlock in the interrupt handler, and the + lock is used in other pcm callbacks, too, then you have to + release the lock before calling + snd_pcm_period_elapsed(), because + snd_pcm_period_elapsed() calls other pcm + callbacks inside. + + + + Typical code would be like: + + + Interrupt Handler Case #1 + +lock); + .... + if (pcm_irq_invoked(chip)) { + /* call updater, unlock before it */ + spin_unlock(&chip->lock); + snd_pcm_period_elapsed(chip->substream); + spin_lock(&chip->lock); + /* acknowledge the interrupt if necessary */ + } + .... + spin_unlock(&chip->lock); + return IRQ_HANDLED; + } +]]> + + + +
+ +
+ High frequency timer interrupts + + This happense when the hardware doesn't generate interrupts + at the period boundary but issues timer interrupts at a fixed + timer rate (e.g. es1968 or ymfpci drivers). + In this case, you need to check the current hardware + position and accumulate the processed sample length at each + interrupt. When the accumulated size exceeds the period + size, call + snd_pcm_period_elapsed() and reset the + accumulator. + + + + Typical code would be like the following. + + + Interrupt Handler Case #2 + +lock); + .... + if (pcm_irq_invoked(chip)) { + unsigned int last_ptr, size; + /* get the current hardware pointer (in frames) */ + last_ptr = get_hw_ptr(chip); + /* calculate the processed frames since the + * last update + */ + if (last_ptr < chip->last_ptr) + size = runtime->buffer_size + last_ptr + - chip->last_ptr; + else + size = last_ptr - chip->last_ptr; + /* remember the last updated point */ + chip->last_ptr = last_ptr; + /* accumulate the size */ + chip->size += size; + /* over the period boundary? */ + if (chip->size >= runtime->period_size) { + /* reset the accumulator */ + chip->size %= runtime->period_size; + /* call updater */ + spin_unlock(&chip->lock); + snd_pcm_period_elapsed(substream); + spin_lock(&chip->lock); + } + /* acknowledge the interrupt if necessary */ + } + .... + spin_unlock(&chip->lock); + return IRQ_HANDLED; + } +]]> + + + +
+ +
+ On calling <function>snd_pcm_period_elapsed()</function> + + In both cases, even if more than one period are elapsed, you + don't have to call + snd_pcm_period_elapsed() many times. Call + only once. And the pcm layer will check the current hardware + pointer and update to the latest status. + +
+
+ +
+ Atomicity + + One of the most important (and thus difficult to debug) problems + in kernel programming are race conditions. + In the Linux kernel, they are usually avoided via spin-locks, mutexes + or semaphores. In general, if a race condition can happen + in an interrupt handler, it has to be managed atomically, and you + have to use a spinlock to protect the critical session. If the + critical section is not in interrupt handler code and + if taking a relatively long time to execute is acceptable, you + should use mutexes or semaphores instead. + + + + As already seen, some pcm callbacks are atomic and some are + not. For example, the hw_params callback is + non-atomic, while trigger callback is + atomic. This means, the latter is called already in a spinlock + held by the PCM middle layer. Please take this atomicity into + account when you choose a locking scheme in the callbacks. + + + + In the atomic callbacks, you cannot use functions which may call + schedule or go to + sleep. Semaphores and mutexes can sleep, + and hence they cannot be used inside the atomic callbacks + (e.g. trigger callback). + To implement some delay in such a callback, please use + udelay() or mdelay(). + + + + All three atomic callbacks (trigger, pointer, and ack) are + called with local interrupts disabled. + + +
+
+ Constraints + + If your chip supports unconventional sample rates, or only the + limited samples, you need to set a constraint for the + condition. + + + + For example, in order to restrict the sample rates in the some + supported values, use + snd_pcm_hw_constraint_list(). + You need to call this function in the open callback. + + + Example of Hardware Constraints + +runtime, 0, + SNDRV_PCM_HW_PARAM_RATE, + &constraints_rates); + if (err < 0) + return err; + .... + } +]]> + + + + + + There are many different constraints. + Look at sound/pcm.h for a complete list. + You can even define your own constraint rules. + For example, let's suppose my_chip can manage a substream of 1 channel + if and only if the format is S16_LE, otherwise it supports any format + specified in the snd_pcm_hardware structure (or in any + other constraint_list). You can build a rule like this: + + + Example of Hardware Constraints for Channels + +min < 2) { + fmt.bits[0] &= SNDRV_PCM_FMTBIT_S16_LE; + return snd_mask_refine(f, &fmt); + } + return 0; + } +]]> + + + + + + Then you need to call this function to add your rule: + + + +runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS, + hw_rule_channels_by_format, 0, SNDRV_PCM_HW_PARAM_FORMAT, + -1); +]]> + + + + + + The rule function is called when an application sets the number of + channels. But an application can set the format before the number of + channels. Thus you also need to define the inverse rule: + + + Example of Hardware Constraints for Channels + +bits[0] == SNDRV_PCM_FMTBIT_S16_LE) { + ch.min = ch.max = 1; + ch.integer = 1; + return snd_interval_refine(c, &ch); + } + return 0; + } +]]> + + + + + + ...and in the open callback: + + +runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT, + hw_rule_format_by_channels, 0, SNDRV_PCM_HW_PARAM_CHANNELS, + -1); +]]> + + + + + + I won't give more details here, rather I + would like to say, Luke, use the source. + +
+ + + + + + + + + Control Interface + +
+ General + + The control interface is used widely for many switches, + sliders, etc. which are accessed from user-space. Its most + important use is the mixer interface. In other words, since ALSA + 0.9.x, all the mixer stuff is implemented on the control kernel API. + + + + ALSA has a well-defined AC97 control module. If your chip + supports only the AC97 and nothing else, you can skip this + section. + + + + The control API is defined in + <sound/control.h>. + Include this file if you want to add your own controls. + +
+ +
+ Definition of Controls + + To create a new control, you need to define the + following three + callbacks: info, + get and + put. Then, define a + struct snd_kcontrol_new record, such as: + + + Definition of a Control + + + + + + + + Most likely the control is created via + snd_ctl_new1(), and in such a case, you can + add the __devinitdata prefix to the + definition as above. + + + + The iface field specifies the control + type, SNDRV_CTL_ELEM_IFACE_XXX, which + is usually MIXER. + Use CARD for global controls that are not + logically part of the mixer. + If the control is closely associated with some specific device on + the sound card, use HWDEP, + PCM, RAWMIDI, + TIMER, or SEQUENCER, and + specify the device number with the + device and + subdevice fields. + + + + The name is the name identifier + string. Since ALSA 0.9.x, the control name is very important, + because its role is classified from its name. There are + pre-defined standard control names. The details are described in + the + Control Names subsection. + + + + The index field holds the index number + of this control. If there are several different controls with + the same name, they can be distinguished by the index + number. This is the case when + several codecs exist on the card. If the index is zero, you can + omit the definition above. + + + + The access field contains the access + type of this control. Give the combination of bit masks, + SNDRV_CTL_ELEM_ACCESS_XXX, there. + The details will be explained in + the + Access Flags subsection. + + + + The private_value field contains + an arbitrary long integer value for this record. When using + the generic info, + get and + put callbacks, you can pass a value + through this field. If several small numbers are necessary, you can + combine them in bitwise. Or, it's possible to give a pointer + (casted to unsigned long) of some record to this field, too. + + + + The tlv field can be used to provide + metadata about the control; see the + + Metadata subsection. + + + + The other three are + + callback functions. + +
+ +
+ Control Names + + There are some standards to define the control names. A + control is usually defined from the three parts as + SOURCE DIRECTION FUNCTION. + + + + The first, SOURCE, specifies the source + of the control, and is a string such as Master, + PCM, CD and + Line. There are many pre-defined sources. + + + + The second, DIRECTION, is one of the + following strings according to the direction of the control: + Playback, Capture, Bypass + Playback and Bypass Capture. Or, it can + be omitted, meaning both playback and capture directions. + + + + The third, FUNCTION, is one of the + following strings according to the function of the control: + Switch, Volume and + Route. + + + + The example of control names are, thus, Master Capture + Switch or PCM Playback Volume. + + + + There are some exceptions: + + +
+ Global capture and playback + + Capture Source, Capture Switch + and Capture Volume are used for the global + capture (input) source, switch and volume. Similarly, + Playback Switch and Playback + Volume are used for the global output gain switch and + volume. + +
+ +
+ Tone-controls + + tone-control switch and volumes are specified like + Tone Control - XXX, e.g. Tone Control - + Switch, Tone Control - Bass, + Tone Control - Center. + +
+ +
+ 3D controls + + 3D-control switches and volumes are specified like 3D + Control - XXX, e.g. 3D Control - + Switch, 3D Control - Center, 3D + Control - Space. + +
+ +
+ Mic boost + + Mic-boost switch is set as Mic Boost or + Mic Boost (6dB). + + + + More precise information can be found in + Documentation/sound/alsa/ControlNames.txt. + +
+
+ +
+ Access Flags + + + The access flag is the bitmask which specifies the access type + of the given control. The default access type is + SNDRV_CTL_ELEM_ACCESS_READWRITE, + which means both read and write are allowed to this control. + When the access flag is omitted (i.e. = 0), it is + considered as READWRITE access as default. + + + + When the control is read-only, pass + SNDRV_CTL_ELEM_ACCESS_READ instead. + In this case, you don't have to define + the put callback. + Similarly, when the control is write-only (although it's a rare + case), you can use the WRITE flag instead, and + you don't need the get callback. + + + + If the control value changes frequently (e.g. the VU meter), + VOLATILE flag should be given. This means + that the control may be changed without + + notification. Applications should poll such + a control constantly. + + + + When the control is inactive, set + the INACTIVE flag, too. + There are LOCK and + OWNER flags to change the write + permissions. + + +
+ +
+ Callbacks + +
+ info callback + + The info callback is used to get + detailed information on this control. This must store the + values of the given struct snd_ctl_elem_info + object. For example, for a boolean control with a single + element: + + + Example of info callback + +type = SNDRV_CTL_ELEM_TYPE_BOOLEAN; + uinfo->count = 1; + uinfo->value.integer.min = 0; + uinfo->value.integer.max = 1; + return 0; + } +]]> + + + + + + The type field specifies the type + of the control. There are BOOLEAN, + INTEGER, ENUMERATED, + BYTES, IEC958 and + INTEGER64. The + count field specifies the + number of elements in this control. For example, a stereo + volume would have count = 2. The + value field is a union, and + the values stored are depending on the type. The boolean and + integer types are identical. + + + + The enumerated type is a bit different from others. You'll + need to set the string for the currently given item index. + + + +type = SNDRV_CTL_ELEM_TYPE_ENUMERATED; + uinfo->count = 1; + uinfo->value.enumerated.items = 4; + if (uinfo->value.enumerated.item > 3) + uinfo->value.enumerated.item = 3; + strcpy(uinfo->value.enumerated.name, + texts[uinfo->value.enumerated.item]); + return 0; + } +]]> + + + + + + Some common info callbacks are available for your convenience: + snd_ctl_boolean_mono_info() and + snd_ctl_boolean_stereo_info(). + Obviously, the former is an info callback for a mono channel + boolean item, just like snd_myctl_mono_info + above, and the latter is for a stereo channel boolean item. + + +
+ +
+ get callback + + + This callback is used to read the current value of the + control and to return to user-space. + + + + For example, + + + Example of get callback + +value.integer.value[0] = get_some_value(chip); + return 0; + } +]]> + + + + + + The value field depends on + the type of control as well as on the info callback. For example, + the sb driver uses this field to store the register offset, + the bit-shift and the bit-mask. The + private_value field is set as follows: + + + + + + and is retrieved in callbacks like + + +private_value & 0xff; + int shift = (kcontrol->private_value >> 16) & 0xff; + int mask = (kcontrol->private_value >> 24) & 0xff; + .... + } +]]> + + + + + + In the get callback, + you have to fill all the elements if the + control has more than one elements, + i.e. count > 1. + In the example above, we filled only one element + (value.integer.value[0]) since it's + assumed as count = 1. + +
+ +
+ put callback + + + This callback is used to write a value from user-space. + + + + For example, + + + Example of put callback + +current_value != + ucontrol->value.integer.value[0]) { + change_current_value(chip, + ucontrol->value.integer.value[0]); + changed = 1; + } + return changed; + } +]]> + + + + As seen above, you have to return 1 if the value is + changed. If the value is not changed, return 0 instead. + If any fatal error happens, return a negative error code as + usual. + + + + As in the get callback, + when the control has more than one elements, + all elements must be evaluated in this callback, too. + +
+ +
+ Callbacks are not atomic + + All these three callbacks are basically not atomic. + +
+
+ +
+ Constructor + + When everything is ready, finally we can create a new + control. To create a control, there are two functions to be + called, snd_ctl_new1() and + snd_ctl_add(). + + + + In the simplest way, you can do like this: + + + + + + + + where my_control is the + struct snd_kcontrol_new object defined above, and chip + is the object pointer to be passed to + kcontrol->private_data + which can be referred to in callbacks. + + + + snd_ctl_new1() allocates a new + snd_kcontrol instance (that's why the definition + of my_control can be with + the __devinitdata + prefix), and snd_ctl_add assigns the given + control component to the card. + +
+ +
+ Change Notification + + If you need to change and update a control in the interrupt + routine, you can call snd_ctl_notify(). For + example, + + + + + + + + This function takes the card pointer, the event-mask, and the + control id pointer for the notification. The event-mask + specifies the types of notification, for example, in the above + example, the change of control values is notified. + The id pointer is the pointer of struct snd_ctl_elem_id + to be notified. + You can find some examples in es1938.c or + es1968.c for hardware volume interrupts. + +
+ +
+ Metadata + + To provide information about the dB values of a mixer control, use + on of the DECLARE_TLV_xxx macros from + <sound/tlv.h> to define a variable + containing this information, set thetlv.p + field to point to this variable, and include the + SNDRV_CTL_ELEM_ACCESS_TLV_READ flag in the + access field; like this: + + + + + + + + + The DECLARE_TLV_DB_SCALE macro defines + information about a mixer control where each step in the control's + value changes the dB value by a constant dB amount. + The first parameter is the name of the variable to be defined. + The second parameter is the minimum value, in units of 0.01 dB. + The third parameter is the step size, in units of 0.01 dB. + Set the fourth parameter to 1 if the minimum value actually mutes + the control. + + + + The DECLARE_TLV_DB_LINEAR macro defines + information about a mixer control where the control's value affects + the output linearly. + The first parameter is the name of the variable to be defined. + The second parameter is the minimum value, in units of 0.01 dB. + The third parameter is the maximum value, in units of 0.01 dB. + If the minimum value mutes the control, set the second parameter to + TLV_DB_GAIN_MUTE. + +
+ + + + + + + + + API for AC97 Codec + +
+ General + + The ALSA AC97 codec layer is a well-defined one, and you don't + have to write much code to control it. Only low-level control + routines are necessary. The AC97 codec API is defined in + <sound/ac97_codec.h>. + +
+ +
+ Full Code Example + + + Example of AC97 Interface + +private_data; + .... + /* read a register value here from the codec */ + return the_register_value; + } + + static void snd_mychip_ac97_write(struct snd_ac97 *ac97, + unsigned short reg, unsigned short val) + { + struct mychip *chip = ac97->private_data; + .... + /* write the given register value to the codec */ + } + + static int snd_mychip_ac97(struct mychip *chip) + { + struct snd_ac97_bus *bus; + struct snd_ac97_template ac97; + int err; + static struct snd_ac97_bus_ops ops = { + .write = snd_mychip_ac97_write, + .read = snd_mychip_ac97_read, + }; + + err = snd_ac97_bus(chip->card, 0, &ops, NULL, &bus); + if (err < 0) + return err; + memset(&ac97, 0, sizeof(ac97)); + ac97.private_data = chip; + return snd_ac97_mixer(bus, &ac97, &chip->ac97); + } + +]]> + + + +
+ +
+ Constructor + + To create an ac97 instance, first call snd_ac97_bus + with an ac97_bus_ops_t record with callback functions. + + + + + + + + The bus record is shared among all belonging ac97 instances. + + + + And then call snd_ac97_mixer() with an + struct snd_ac97_template + record together with the bus pointer created above. + + + +ac97); +]]> + + + + where chip->ac97 is a pointer to a newly created + ac97_t instance. + In this case, the chip pointer is set as the private data, so that + the read/write callback functions can refer to this chip instance. + This instance is not necessarily stored in the chip + record. If you need to change the register values from the + driver, or need the suspend/resume of ac97 codecs, keep this + pointer to pass to the corresponding functions. + +
+ +
+ Callbacks + + The standard callbacks are read and + write. Obviously they + correspond to the functions for read and write accesses to the + hardware low-level codes. + + + + The read callback returns the + register value specified in the argument. + + + +private_data; + .... + return the_register_value; + } +]]> + + + + Here, the chip can be cast from ac97->private_data. + + + + Meanwhile, the write callback is + used to set the register value. + + + + + + + + + + These callbacks are non-atomic like the control API callbacks. + + + + There are also other callbacks: + reset, + wait and + init. + + + + The reset callback is used to reset + the codec. If the chip requires a special kind of reset, you can + define this callback. + + + + The wait callback is used to + add some waiting time in the standard initialization of the codec. If the + chip requires the extra waiting time, define this callback. + + + + The init callback is used for + additional initialization of the codec. + +
+ +
+ Updating Registers in The Driver + + If you need to access to the codec from the driver, you can + call the following functions: + snd_ac97_write(), + snd_ac97_read(), + snd_ac97_update() and + snd_ac97_update_bits(). + + + + Both snd_ac97_write() and + snd_ac97_update() functions are used to + set a value to the given register + (AC97_XXX). The difference between them is + that snd_ac97_update() doesn't write a + value if the given value has been already set, while + snd_ac97_write() always rewrites the + value. + + + + + + + + + + snd_ac97_read() is used to read the value + of the given register. For example, + + + + + + + + + + snd_ac97_update_bits() is used to update + some bits in the given register. + + + + + + + + + + Also, there is a function to change the sample rate (of a + given register such as + AC97_PCM_FRONT_DAC_RATE) when VRA or + DRA is supported by the codec: + snd_ac97_set_rate(). + + + + + + + + + + The following registers are available to set the rate: + AC97_PCM_MIC_ADC_RATE, + AC97_PCM_FRONT_DAC_RATE, + AC97_PCM_LR_ADC_RATE, + AC97_SPDIF. When + AC97_SPDIF is specified, the register is + not really changed but the corresponding IEC958 status bits will + be updated. + +
+ +
+ Clock Adjustment + + In some chips, the clock of the codec isn't 48000 but using a + PCI clock (to save a quartz!). In this case, change the field + bus->clock to the corresponding + value. For example, intel8x0 + and es1968 drivers have their own function to read from the clock. + +
+ +
+ Proc Files + + The ALSA AC97 interface will create a proc file such as + /proc/asound/card0/codec97#0/ac97#0-0 and + ac97#0-0+regs. You can refer to these files to + see the current status and registers of the codec. + +
+ +
+ Multiple Codecs + + When there are several codecs on the same card, you need to + call snd_ac97_mixer() multiple times with + ac97.num=1 or greater. The num field + specifies the codec number. + + + + If you set up multiple codecs, you either need to write + different callbacks for each codec or check + ac97->num in the callback routines. + +
+ + + + + + + + + MIDI (MPU401-UART) Interface + +
+ General + + Many soundcards have built-in MIDI (MPU401-UART) + interfaces. When the soundcard supports the standard MPU401-UART + interface, most likely you can use the ALSA MPU401-UART API. The + MPU401-UART API is defined in + <sound/mpu401.h>. + + + + Some soundchips have a similar but slightly different + implementation of mpu401 stuff. For example, emu10k1 has its own + mpu401 routines. + +
+ +
+ Constructor + + To create a rawmidi object, call + snd_mpu401_uart_new(). + + + + + + + + + + The first argument is the card pointer, and the second is the + index of this component. You can create up to 8 rawmidi + devices. + + + + The third argument is the type of the hardware, + MPU401_HW_XXX. If it's not a special one, + you can use MPU401_HW_MPU401. + + + + The 4th argument is the I/O port address. Many + backward-compatible MPU401 have an I/O port such as 0x330. Or, it + might be a part of its own PCI I/O region. It depends on the + chip design. + + + + The 5th argument is a bitflag for additional information. + When the I/O port address above is part of the PCI I/O + region, the MPU401 I/O port might have been already allocated + (reserved) by the driver itself. In such a case, pass a bit flag + MPU401_INFO_INTEGRATED, + and the mpu401-uart layer will allocate the I/O ports by itself. + + + + When the controller supports only the input or output MIDI stream, + pass the MPU401_INFO_INPUT or + MPU401_INFO_OUTPUT bitflag, respectively. + Then the rawmidi instance is created as a single stream. + + + + MPU401_INFO_MMIO bitflag is used to change + the access method to MMIO (via readb and writeb) instead of + iob and outb. In this case, you have to pass the iomapped address + to snd_mpu401_uart_new(). + + + + When MPU401_INFO_TX_IRQ is set, the output + stream isn't checked in the default interrupt handler. The driver + needs to call snd_mpu401_uart_interrupt_tx() + by itself to start processing the output stream in the irq handler. + + + + Usually, the port address corresponds to the command port and + port + 1 corresponds to the data port. If not, you may change + the cport field of + struct snd_mpu401 manually + afterward. However, snd_mpu401 pointer is not + returned explicitly by + snd_mpu401_uart_new(). You need to cast + rmidi->private_data to + snd_mpu401 explicitly, + + + +private_data; +]]> + + + + and reset the cport as you like: + + + +cport = my_own_control_port; +]]> + + + + + + The 6th argument specifies the irq number for UART. If the irq + is already allocated, pass 0 to the 7th argument + (irq_flags). Otherwise, pass the flags + for irq allocation + (SA_XXX bits) to it, and the irq will be + reserved by the mpu401-uart layer. If the card doesn't generate + UART interrupts, pass -1 as the irq number. Then a timer + interrupt will be invoked for polling. + +
+ +
+ Interrupt Handler + + When the interrupt is allocated in + snd_mpu401_uart_new(), the private + interrupt handler is used, hence you don't have anything else to do + than creating the mpu401 stuff. Otherwise, you have to call + snd_mpu401_uart_interrupt() explicitly when + a UART interrupt is invoked and checked in your own interrupt + handler. + + + + In this case, you need to pass the private_data of the + returned rawmidi object from + snd_mpu401_uart_new() as the second + argument of snd_mpu401_uart_interrupt(). + + + +private_data, regs); +]]> + + + +
+ + + + + + + + + RawMIDI Interface + +
+ Overview + + + The raw MIDI interface is used for hardware MIDI ports that can + be accessed as a byte stream. It is not used for synthesizer + chips that do not directly understand MIDI. + + + + ALSA handles file and buffer management. All you have to do is + to write some code to move data between the buffer and the + hardware. + + + + The rawmidi API is defined in + <sound/rawmidi.h>. + +
+ +
+ Constructor + + + To create a rawmidi device, call the + snd_rawmidi_new function: + + +card, "MyMIDI", 0, outs, ins, &rmidi); + if (err < 0) + return err; + rmidi->private_data = chip; + strcpy(rmidi->name, "My MIDI"); + rmidi->info_flags = SNDRV_RAWMIDI_INFO_OUTPUT | + SNDRV_RAWMIDI_INFO_INPUT | + SNDRV_RAWMIDI_INFO_DUPLEX; +]]> + + + + + + The first argument is the card pointer, the second argument is + the ID string. + + + + The third argument is the index of this component. You can + create up to 8 rawmidi devices. + + + + The fourth and fifth arguments are the number of output and + input substreams, respectively, of this device (a substream is + the equivalent of a MIDI port). + + + + Set the info_flags field to specify + the capabilities of the device. + Set SNDRV_RAWMIDI_INFO_OUTPUT if there is + at least one output port, + SNDRV_RAWMIDI_INFO_INPUT if there is at + least one input port, + and SNDRV_RAWMIDI_INFO_DUPLEX if the device + can handle output and input at the same time. + + + + After the rawmidi device is created, you need to set the + operators (callbacks) for each substream. There are helper + functions to set the operators for all the substreams of a device: + + + + + + + + + The operators are usually defined like this: + + + + + + These callbacks are explained in the Callbacks + section. + + + + If there are more than one substream, you should give a + unique name to each of them: + + +streams[SNDRV_RAWMIDI_STREAM_OUTPUT].substreams, + list { + sprintf(substream->name, "My MIDI Port %d", substream->number + 1); + } + /* same for SNDRV_RAWMIDI_STREAM_INPUT */ +]]> + + + +
+ +
+ Callbacks + + + In all the callbacks, the private data that you've set for the + rawmidi device can be accessed as + substream->rmidi->private_data. + + + + + If there is more than one port, your callbacks can determine the + port index from the struct snd_rawmidi_substream data passed to each + callback: + + +number; +]]> + + + + +
+ <function>open</function> callback + + + + + + + + + This is called when a substream is opened. + You can initialize the hardware here, but you shouldn't + start transmitting/receiving data yet. + +
+ +
+ <function>close</function> callback + + + + + + + + + Guess what. + + + + The open and close + callbacks of a rawmidi device are serialized with a mutex, + and can sleep. + +
+ +
+ <function>trigger</function> callback for output + substreams + + + + + + + + + This is called with a nonzero up + parameter when there is some data in the substream buffer that + must be transmitted. + + + + To read data from the buffer, call + snd_rawmidi_transmit_peek. It will + return the number of bytes that have been read; this will be + less than the number of bytes requested when there are no more + data in the buffer. + After the data have been transmitted successfully, call + snd_rawmidi_transmit_ack to remove the + data from the substream buffer: + + + + + + + + + If you know beforehand that the hardware will accept data, you + can use the snd_rawmidi_transmit function + which reads some data and removes them from the buffer at once: + + + + + + + + + If you know beforehand how many bytes you can accept, you can + use a buffer size greater than one with the + snd_rawmidi_transmit* functions. + + + + The trigger callback must not sleep. If + the hardware FIFO is full before the substream buffer has been + emptied, you have to continue transmitting data later, either + in an interrupt handler, or with a timer if the hardware + doesn't have a MIDI transmit interrupt. + + + + The trigger callback is called with a + zero up parameter when the transmission + of data should be aborted. + +
+ +
+ <function>trigger</function> callback for input + substreams + + + + + + + + + This is called with a nonzero up + parameter to enable receiving data, or with a zero + up parameter do disable receiving data. + + + + The trigger callback must not sleep; the + actual reading of data from the device is usually done in an + interrupt handler. + + + + When data reception is enabled, your interrupt handler should + call snd_rawmidi_receive for all received + data: + + + + + + +
+ +
+ <function>drain</function> callback + + + + + + + + + This is only used with output substreams. This function should wait + until all data read from the substream buffer have been transmitted. + This ensures that the device can be closed and the driver unloaded + without losing data. + + + + This callback is optional. If you do not set + drain in the struct snd_rawmidi_ops + structure, ALSA will simply wait for 50 milliseconds + instead. + +
+
+ + + + + + + + + Miscellaneous Devices + +
+ FM OPL3 + + The FM OPL3 is still used in many chips (mainly for backward + compatibility). ALSA has a nice OPL3 FM control layer, too. The + OPL3 API is defined in + <sound/opl3.h>. + + + + FM registers can be directly accessed through the direct-FM API, + defined in <sound/asound_fm.h>. In + ALSA native mode, FM registers are accessed through + the Hardware-Dependant Device direct-FM extension API, whereas in + OSS compatible mode, FM registers can be accessed with the OSS + direct-FM compatible API in /dev/dmfmX device. + + + + To create the OPL3 component, you have two functions to + call. The first one is a constructor for the opl3_t + instance. + + + + + + + + + + The first argument is the card pointer, the second one is the + left port address, and the third is the right port address. In + most cases, the right port is placed at the left port + 2. + + + + The fourth argument is the hardware type. + + + + When the left and right ports have been already allocated by + the card driver, pass non-zero to the fifth argument + (integrated). Otherwise, the opl3 module will + allocate the specified ports by itself. + + + + When the accessing the hardware requires special method + instead of the standard I/O access, you can create opl3 instance + separately with snd_opl3_new(). + + + + + + + + + + Then set command, + private_data and + private_free for the private + access function, the private data and the destructor. + The l_port and r_port are not necessarily set. Only the + command must be set properly. You can retrieve the data + from the opl3->private_data field. + + + + After creating the opl3 instance via snd_opl3_new(), + call snd_opl3_init() to initialize the chip to the + proper state. Note that snd_opl3_create() always + calls it internally. + + + + If the opl3 instance is created successfully, then create a + hwdep device for this opl3. + + + + + + + + + + The first argument is the opl3_t instance you + created, and the second is the index number, usually 0. + + + + The third argument is the index-offset for the sequencer + client assigned to the OPL3 port. When there is an MPU401-UART, + give 1 for here (UART always takes 0). + +
+ +
+ Hardware-Dependent Devices + + Some chips need user-space access for special + controls or for loading the micro code. In such a case, you can + create a hwdep (hardware-dependent) device. The hwdep API is + defined in <sound/hwdep.h>. You can + find examples in opl3 driver or + isa/sb/sb16_csp.c. + + + + The creation of the hwdep instance is done via + snd_hwdep_new(). + + + + + + + + where the third argument is the index number. + + + + You can then pass any pointer value to the + private_data. + If you assign a private data, you should define the + destructor, too. The destructor function is set in + the private_free field. + + + +private_data = p; + hw->private_free = mydata_free; +]]> + + + + and the implementation of the destructor would be: + + + +private_data; + kfree(p); + } +]]> + + + + + + The arbitrary file operations can be defined for this + instance. The file operators are defined in + the ops table. For example, assume that + this chip needs an ioctl. + + + +ops.open = mydata_open; + hw->ops.ioctl = mydata_ioctl; + hw->ops.release = mydata_release; +]]> + + + + And implement the callback functions as you like. + +
+ +
+ IEC958 (S/PDIF) + + Usually the controls for IEC958 devices are implemented via + the control interface. There is a macro to compose a name string for + IEC958 controls, SNDRV_CTL_NAME_IEC958() + defined in <include/asound.h>. + + + + There are some standard controls for IEC958 status bits. These + controls use the type SNDRV_CTL_ELEM_TYPE_IEC958, + and the size of element is fixed as 4 bytes array + (value.iec958.status[x]). For the info + callback, you don't specify + the value field for this type (the count field must be set, + though). + + + + IEC958 Playback Con Mask is used to return the + bit-mask for the IEC958 status bits of consumer mode. Similarly, + IEC958 Playback Pro Mask returns the bitmask for + professional mode. They are read-only controls, and are defined + as MIXER controls (iface = + SNDRV_CTL_ELEM_IFACE_MIXER). + + + + Meanwhile, IEC958 Playback Default control is + defined for getting and setting the current default IEC958 + bits. Note that this one is usually defined as a PCM control + (iface = SNDRV_CTL_ELEM_IFACE_PCM), + although in some places it's defined as a MIXER control. + + + + In addition, you can define the control switches to + enable/disable or to set the raw bit mode. The implementation + will depend on the chip, but the control should be named as + IEC958 xxx, preferably using + the SNDRV_CTL_NAME_IEC958() macro. + + + + You can find several cases, for example, + pci/emu10k1, + pci/ice1712, or + pci/cmipci.c. + +
+ + + + + + + + + Buffer and Memory Management + +
+ Buffer Types + + ALSA provides several different buffer allocation functions + depending on the bus and the architecture. All these have a + consistent API. The allocation of physically-contiguous pages is + done via + snd_malloc_xxx_pages() function, where xxx + is the bus type. + + + + The allocation of pages with fallback is + snd_malloc_xxx_pages_fallback(). This + function tries to allocate the specified pages but if the pages + are not available, it tries to reduce the page sizes until + enough space is found. + + + + The release the pages, call + snd_free_xxx_pages() function. + + + + Usually, ALSA drivers try to allocate and reserve + a large contiguous physical space + at the time the module is loaded for the later use. + This is called pre-allocation. + As already written, you can call the following function at + pcm instance construction time (in the case of PCI bus). + + + + + + + + where size is the byte size to be + pre-allocated and the max is the maximum + size to be changed via the prealloc proc file. + The allocator will try to get an area as large as possible + within the given size. + + + + The second argument (type) and the third argument (device pointer) + are dependent on the bus. + In the case of the ISA bus, pass snd_dma_isa_data() + as the third argument with SNDRV_DMA_TYPE_DEV type. + For the continuous buffer unrelated to the bus can be pre-allocated + with SNDRV_DMA_TYPE_CONTINUOUS type and the + snd_dma_continuous_data(GFP_KERNEL) device pointer, + where GFP_KERNEL is the kernel allocation flag to + use. + For the PCI scatter-gather buffers, use + SNDRV_DMA_TYPE_DEV_SG with + snd_dma_pci_data(pci) + (see the + Non-Contiguous Buffers + section). + + + + Once the buffer is pre-allocated, you can use the + allocator in the hw_params callback: + + + + + + + + Note that you have to pre-allocate to use this function. + +
+ +
+ External Hardware Buffers + + Some chips have their own hardware buffers and the DMA + transfer from the host memory is not available. In such a case, + you need to either 1) copy/set the audio data directly to the + external hardware buffer, or 2) make an intermediate buffer and + copy/set the data from it to the external hardware buffer in + interrupts (or in tasklets, preferably). + + + + The first case works fine if the external hardware buffer is large + enough. This method doesn't need any extra buffers and thus is + more effective. You need to define the + copy and + silence callbacks for + the data transfer. However, there is a drawback: it cannot + be mmapped. The examples are GUS's GF1 PCM or emu8000's + wavetable PCM. + + + + The second case allows for mmap on the buffer, although you have + to handle an interrupt or a tasklet to transfer the data + from the intermediate buffer to the hardware buffer. You can find an + example in the vxpocket driver. + + + + Another case is when the chip uses a PCI memory-map + region for the buffer instead of the host memory. In this case, + mmap is available only on certain architectures like the Intel one. + In non-mmap mode, the data cannot be transferred as in the normal + way. Thus you need to define the copy and + silence callbacks as well, + as in the cases above. The examples are found in + rme32.c and rme96.c. + + + + The implementation of the copy and + silence callbacks depends upon + whether the hardware supports interleaved or non-interleaved + samples. The copy callback is + defined like below, a bit + differently depending whether the direction is playback or + capture: + + + + + + + + + + In the case of interleaved samples, the second argument + (channel) is not used. The third argument + (pos) points the + current position offset in frames. + + + + The meaning of the fourth argument is different between + playback and capture. For playback, it holds the source data + pointer, and for capture, it's the destination data pointer. + + + + The last argument is the number of frames to be copied. + + + + What you have to do in this callback is again different + between playback and capture directions. In the + playback case, you copy the given amount of data + (count) at the specified pointer + (src) to the specified offset + (pos) on the hardware buffer. When + coded like memcpy-like way, the copy would be like: + + + + + + + + + + For the capture direction, you copy the given amount of + data (count) at the specified offset + (pos) on the hardware buffer to the + specified pointer (dst). + + + + + + + + Note that both the position and the amount of data are given + in frames. + + + + In the case of non-interleaved samples, the implementation + will be a bit more complicated. + + + + You need to check the channel argument, and if it's -1, copy + the whole channels. Otherwise, you have to copy only the + specified channel. Please check + isa/gus/gus_pcm.c as an example. + + + + The silence callback is also + implemented in a similar way. + + + + + + + + + + The meanings of arguments are the same as in the + copy + callback, although there is no src/dst + argument. In the case of interleaved samples, the channel + argument has no meaning, as well as on + copy callback. + + + + The role of silence callback is to + set the given amount + (count) of silence data at the + specified offset (pos) on the hardware + buffer. Suppose that the data format is signed (that is, the + silent-data is 0), and the implementation using a memset-like + function would be like: + + + + + + + + + + In the case of non-interleaved samples, again, the + implementation becomes a bit more complicated. See, for example, + isa/gus/gus_pcm.c. + +
+ +
+ Non-Contiguous Buffers + + If your hardware supports the page table as in emu10k1 or the + buffer descriptors as in via82xx, you can use the scatter-gather + (SG) DMA. ALSA provides an interface for handling SG-buffers. + The API is provided in <sound/pcm.h>. + + + + For creating the SG-buffer handler, call + snd_pcm_lib_preallocate_pages() or + snd_pcm_lib_preallocate_pages_for_all() + with SNDRV_DMA_TYPE_DEV_SG + in the PCM constructor like other PCI pre-allocator. + You need to pass snd_dma_pci_data(pci), + where pci is the struct pci_dev pointer + of the chip as well. + The struct snd_sg_buf instance is created as + substream->dma_private. You can cast + the pointer like: + + + +dma_private; +]]> + + + + + + Then call snd_pcm_lib_malloc_pages() + in the hw_params callback + as well as in the case of normal PCI buffer. + The SG-buffer handler will allocate the non-contiguous kernel + pages of the given size and map them onto the virtually contiguous + memory. The virtual pointer is addressed in runtime->dma_area. + The physical address (runtime->dma_addr) is set to zero, + because the buffer is physically non-contigous. + The physical address table is set up in sgbuf->table. + You can get the physical address at a certain offset via + snd_pcm_sgbuf_get_addr(). + + + + When a SG-handler is used, you need to set + snd_pcm_sgbuf_ops_page as + the page callback. + (See + page callback section.) + + + + To release the data, call + snd_pcm_lib_free_pages() in the + hw_free callback as usual. + +
+ +
+ Vmalloc'ed Buffers + + It's possible to use a buffer allocated via + vmalloc, for example, for an intermediate + buffer. Since the allocated pages are not contiguous, you need + to set the page callback to obtain + the physical address at every offset. + + + + The implementation of page callback + would be like this: + + + + + + /* get the physical page pointer on the given offset */ + static struct page *mychip_page(struct snd_pcm_substream *substream, + unsigned long offset) + { + void *pageptr = substream->runtime->dma_area + offset; + return vmalloc_to_page(pageptr); + } +]]> + + + +
+ + + + + + + + + Proc Interface + + ALSA provides an easy interface for procfs. The proc files are + very useful for debugging. I recommend you set up proc files if + you write a driver and want to get a running status or register + dumps. The API is found in + <sound/info.h>. + + + + To create a proc file, call + snd_card_proc_new(). + + + + + + + + where the second argument specifies the name of the proc file to be + created. The above example will create a file + my-file under the card directory, + e.g. /proc/asound/card0/my-file. + + + + Like other components, the proc entry created via + snd_card_proc_new() will be registered and + released automatically in the card registration and release + functions. + + + + When the creation is successful, the function stores a new + instance in the pointer given in the third argument. + It is initialized as a text proc file for read only. To use + this proc file as a read-only text file as it is, set the read + callback with a private data via + snd_info_set_text_ops(). + + + + + + + + where the second argument (chip) is the + private data to be used in the callbacks. The third parameter + specifies the read buffer size and the fourth + (my_proc_read) is the callback function, which + is defined like + + + + + + + + + + + In the read callback, use snd_iprintf() for + output strings, which works just like normal + printf(). For example, + + + +private_data; + + snd_iprintf(buffer, "This is my chip!\n"); + snd_iprintf(buffer, "Port = %ld\n", chip->port); + } +]]> + + + + + + The file permissions can be changed afterwards. As default, it's + set as read only for all users. If you want to add write + permission for the user (root as default), do as follows: + + + +mode = S_IFREG | S_IRUGO | S_IWUSR; +]]> + + + + and set the write buffer size and the callback + + + +c.text.write = my_proc_write; +]]> + + + + + + For the write callback, you can use + snd_info_get_line() to get a text line, and + snd_info_get_str() to retrieve a string from + the line. Some examples are found in + core/oss/mixer_oss.c, core/oss/and + pcm_oss.c. + + + + For a raw-data proc-file, set the attributes as follows: + + + +content = SNDRV_INFO_CONTENT_DATA; + entry->private_data = chip; + entry->c.ops = &my_file_io_ops; + entry->size = 4096; + entry->mode = S_IFREG | S_IRUGO; +]]> + + + + + + The callback is much more complicated than the text-file + version. You need to use a low-level I/O functions such as + copy_from/to_user() to transfer the + data. + + + + local_max_size) + size = local_max_size - pos; + if (copy_to_user(buf, local_data + pos, size)) + return -EFAULT; + return size; + } +]]> + + + + + + + + + + + + Power Management + + If the chip is supposed to work with suspend/resume + functions, you need to add power-management code to the + driver. The additional code for power-management should be + ifdef'ed with + CONFIG_PM. + + + + If the driver fully supports suspend/resume + that is, the device can be + properly resumed to its state when suspend was called, + you can set the SNDRV_PCM_INFO_RESUME flag + in the pcm info field. Usually, this is possible when the + registers of the chip can be safely saved and restored to + RAM. If this is set, the trigger callback is called with + SNDRV_PCM_TRIGGER_RESUME after the resume + callback completes. + + + + Even if the driver doesn't support PM fully but + partial suspend/resume is still possible, it's still worthy to + implement suspend/resume callbacks. In such a case, applications + would reset the status by calling + snd_pcm_prepare() and restart the stream + appropriately. Hence, you can define suspend/resume callbacks + below but don't set SNDRV_PCM_INFO_RESUME + info flag to the PCM. + + + + Note that the trigger with SUSPEND can always be called when + snd_pcm_suspend_all is called, + regardless of the SNDRV_PCM_INFO_RESUME flag. + The RESUME flag affects only the behavior + of snd_pcm_resume(). + (Thus, in theory, + SNDRV_PCM_TRIGGER_RESUME isn't needed + to be handled in the trigger callback when no + SNDRV_PCM_INFO_RESUME flag is set. But, + it's better to keep it for compatibility reasons.) + + + In the earlier version of ALSA drivers, a common + power-management layer was provided, but it has been removed. + The driver needs to define the suspend/resume hooks according to + the bus the device is connected to. In the case of PCI drivers, the + callbacks look like below: + + + + + + + + + + The scheme of the real suspend job is as follows. + + + Retrieve the card and the chip data. + Call snd_power_change_state() with + SNDRV_CTL_POWER_D3hot to change the + power status. + Call snd_pcm_suspend_all() to suspend the running PCM streams. + If AC97 codecs are used, call + snd_ac97_suspend() for each codec. + Save the register values if necessary. + Stop the hardware if necessary. + Disable the PCI device by calling + pci_disable_device(). Then, call + pci_save_state() at last. + + + + + A typical code would be like: + + + +private_data; + /* (2) */ + snd_power_change_state(card, SNDRV_CTL_POWER_D3hot); + /* (3) */ + snd_pcm_suspend_all(chip->pcm); + /* (4) */ + snd_ac97_suspend(chip->ac97); + /* (5) */ + snd_mychip_save_registers(chip); + /* (6) */ + snd_mychip_stop_hardware(chip); + /* (7) */ + pci_disable_device(pci); + pci_save_state(pci); + return 0; + } +]]> + + + + + + The scheme of the real resume job is as follows. + + + Retrieve the card and the chip data. + Set up PCI. First, call pci_restore_state(). + Then enable the pci device again by calling pci_enable_device(). + Call pci_set_master() if necessary, too. + Re-initialize the chip. + Restore the saved registers if necessary. + Resume the mixer, e.g. calling + snd_ac97_resume(). + Restart the hardware (if any). + Call snd_power_change_state() with + SNDRV_CTL_POWER_D0 to notify the processes. + + + + + A typical code would be like: + + + +private_data; + /* (2) */ + pci_restore_state(pci); + pci_enable_device(pci); + pci_set_master(pci); + /* (3) */ + snd_mychip_reinit_chip(chip); + /* (4) */ + snd_mychip_restore_registers(chip); + /* (5) */ + snd_ac97_resume(chip->ac97); + /* (6) */ + snd_mychip_restart_chip(chip); + /* (7) */ + snd_power_change_state(card, SNDRV_CTL_POWER_D0); + return 0; + } +]]> + + + + + + As shown in the above, it's better to save registers after + suspending the PCM operations via + snd_pcm_suspend_all() or + snd_pcm_suspend(). It means that the PCM + streams are already stoppped when the register snapshot is + taken. But, remember that you don't have to restart the PCM + stream in the resume callback. It'll be restarted via + trigger call with SNDRV_PCM_TRIGGER_RESUME + when necessary. + + + + OK, we have all callbacks now. Let's set them up. In the + initialization of the card, make sure that you can get the chip + data from the card instance, typically via + private_data field, in case you + created the chip data individually. + + + +private_data = chip; + .... + } +]]> + + + + When you created the chip data with + snd_card_create(), it's anyway accessible + via private_data field. + + + +private_data; + .... + } +]]> + + + + + + + If you need a space to save the registers, allocate the + buffer for it here, too, since it would be fatal + if you cannot allocate a memory in the suspend phase. + The allocated buffer should be released in the corresponding + destructor. + + + + And next, set suspend/resume callbacks to the pci_driver. + + + + + + + + + + + + + + + + Module Parameters + + There are standard module options for ALSA. At least, each + module should have the index, + id and enable + options. + + + + If the module supports multiple cards (usually up to + 8 = SNDRV_CARDS cards), they should be + arrays. The default initial values are defined already as + constants for easier programming: + + + + + + + + + + If the module supports only a single card, they could be single + variables, instead. enable option is not + always necessary in this case, but it would be better to have a + dummy option for compatibility. + + + + The module parameters must be declared with the standard + module_param()(), + module_param_array()() and + MODULE_PARM_DESC() macros. + + + + The typical coding would be like below: + + + + + + + + + + Also, don't forget to define the module description, classes, + license and devices. Especially, the recent modprobe requires to + define the module license as GPL, etc., otherwise the system is + shown as tainted. + + + + + + + + + + + + + + + + How To Put Your Driver Into ALSA Tree +
+ General + + So far, you've learned how to write the driver codes. + And you might have a question now: how to put my own + driver into the ALSA driver tree? + Here (finally :) the standard procedure is described briefly. + + + + Suppose that you create a new PCI driver for the card + xyz. The card module name would be + snd-xyz. The new driver is usually put into the alsa-driver + tree, alsa-driver/pci directory in + the case of PCI cards. + Then the driver is evaluated, audited and tested + by developers and users. After a certain time, the driver + will go to the alsa-kernel tree (to the corresponding directory, + such as alsa-kernel/pci) and eventually + will be integrated into the Linux 2.6 tree (the directory would be + linux/sound/pci). + + + + In the following sections, the driver code is supposed + to be put into alsa-driver tree. The two cases are covered: + a driver consisting of a single source file and one consisting + of several source files. + +
+ +
+ Driver with A Single Source File + + + + + Modify alsa-driver/pci/Makefile + + + + Suppose you have a file xyz.c. Add the following + two lines + + + + + + + + + + + Create the Kconfig entry + + + + Add the new entry of Kconfig for your xyz driver. + + + + + + + the line, select SND_PCM, specifies that the driver xyz supports + PCM. In addition to SND_PCM, the following components are + supported for select command: + SND_RAWMIDI, SND_TIMER, SND_HWDEP, SND_MPU401_UART, + SND_OPL3_LIB, SND_OPL4_LIB, SND_VX_LIB, SND_AC97_CODEC. + Add the select command for each supported component. + + + + Note that some selections imply the lowlevel selections. + For example, PCM includes TIMER, MPU401_UART includes RAWMIDI, + AC97_CODEC includes PCM, and OPL3_LIB includes HWDEP. + You don't need to give the lowlevel selections again. + + + + For the details of Kconfig script, refer to the kbuild + documentation. + + + + + + + Run cvscompile script to re-generate the configure script and + build the whole stuff again. + + + + +
+ +
+ Drivers with Several Source Files + + Suppose that the driver snd-xyz have several source files. + They are located in the new subdirectory, + pci/xyz. + + + + + Add a new directory (xyz) in + alsa-driver/pci/Makefile as below + + + + + + + + + + + + Under the directory xyz, create a Makefile + + + Sample Makefile for a driver xyz + + + + + + + + + + Create the Kconfig entry + + + + This procedure is as same as in the last section. + + + + + + Run cvscompile script to re-generate the configure script and + build the whole stuff again. + + + + +
+ + + + + + + + Useful Functions + +
+ <function>snd_printk()</function> and friends + + ALSA provides a verbose version of the + printk() function. If a kernel config + CONFIG_SND_VERBOSE_PRINTK is set, this + function prints the given message together with the file name + and the line of the caller. The KERN_XXX + prefix is processed as + well as the original printk() does, so it's + recommended to add this prefix, e.g. + + + + + + + + + + There are also printk()'s for + debugging. snd_printd() can be used for + general debugging purposes. If + CONFIG_SND_DEBUG is set, this function is + compiled, and works just like + snd_printk(). If the ALSA is compiled + without the debugging flag, it's ignored. + + + + snd_printdd() is compiled in only when + CONFIG_SND_DEBUG_VERBOSE is set. Please note + that CONFIG_SND_DEBUG_VERBOSE is not set as default + even if you configure the alsa-driver with + option. You need to give + explicitly option instead. + +
+ +
+ <function>snd_BUG()</function> + + It shows the BUG? message and + stack trace as well as snd_BUG_ON at the point. + It's useful to show that a fatal error happens there. + + + When no debug flag is set, this macro is ignored. + +
+ +
+ <function>snd_BUG_ON()</function> + + snd_BUG_ON() macro is similar with + WARN_ON() macro. For example, + + + + + + + + or it can be used as the condition, + + + + + + + + + + The macro takes an conditional expression to evaluate. + When CONFIG_SND_DEBUG, is set, the + expression is actually evaluated. If it's non-zero, it shows + the warning message such as + BUG? (xxx) + normally followed by stack trace. It returns the evaluated + value. + When no CONFIG_SND_DEBUG is set, this + macro always returns zero. + + +
+ + + + + + + + + Acknowledgments + + I would like to thank Phil Kerr for his help for improvement and + corrections of this document. + + + Kevin Conder reformatted the original plain-text to the + DocBook format. + + + Giuliano Pochini corrected typos and contributed the example codes + in the hardware constraints section. + + + diff --git a/Documentation/sound/alsa/DocBook/alsa-driver-api.tmpl b/Documentation/sound/alsa/DocBook/alsa-driver-api.tmpl deleted file mode 100644 index 0230a96f056..00000000000 --- a/Documentation/sound/alsa/DocBook/alsa-driver-api.tmpl +++ /dev/null @@ -1,109 +0,0 @@ - - - - - - - - - The ALSA Driver API - - - - This document is free; you can redistribute it and/or modify it - under the terms of the GNU General Public License as published by - the Free Software Foundation; either version 2 of the License, or - (at your option) any later version. - - - - This document is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the - implied warranty of MERCHANTABILITY or FITNESS FOR A - PARTICULAR PURPOSE. See the GNU General Public License - for more details. - - - - You should have received a copy of the GNU General Public - License along with this program; if not, write to the Free - Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, - MA 02111-1307 USA - - - - - - - - Management of Cards and Devices - Card Management -!Esound/core/init.c - - Device Components -!Esound/core/device.c - - Module requests and Device File Entries -!Esound/core/sound.c - - Memory Management Helpers -!Esound/core/memory.c -!Esound/core/memalloc.c - - - PCM API - PCM Core -!Esound/core/pcm.c -!Esound/core/pcm_lib.c -!Esound/core/pcm_native.c - - PCM Format Helpers -!Esound/core/pcm_misc.c - - PCM Memory Management -!Esound/core/pcm_memory.c - - - Control/Mixer API - General Control Interface -!Esound/core/control.c - - AC97 Codec API -!Esound/pci/ac97/ac97_codec.c -!Esound/pci/ac97/ac97_pcm.c - - Virtual Master Control API -!Esound/core/vmaster.c -!Iinclude/sound/control.h - - - MIDI API - Raw MIDI API -!Esound/core/rawmidi.c - - MPU401-UART API -!Esound/drivers/mpu401/mpu401_uart.c - - - Proc Info API - Proc Info Interface -!Esound/core/info.c - - - Miscellaneous Functions - Hardware-Dependent Devices API -!Esound/core/hwdep.c - - Jack Abstraction Layer API -!Esound/core/jack.c - - ISA DMA Helpers -!Esound/core/isadma.c - - Other Helper Macros -!Iinclude/sound/core.h - - - - diff --git a/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl b/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl deleted file mode 100644 index 46b08fef374..00000000000 --- a/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl +++ /dev/null @@ -1,6216 +0,0 @@ - - - - - - - - - Writing an ALSA Driver - - Takashi - Iwai - -
- tiwai@suse.de -
- - - - Oct 15, 2007 - 0.3.7 - - - - This document describes how to write an ALSA (Advanced Linux - Sound Architecture) driver. - - - - - - Copyright (c) 2002-2005 Takashi Iwai tiwai@suse.de - - - - This document is free; you can redistribute it and/or modify it - under the terms of the GNU General Public License as published by - the Free Software Foundation; either version 2 of the License, or - (at your option) any later version. - - - - This document is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the - implied warranty of MERCHANTABILITY or FITNESS FOR A - PARTICULAR PURPOSE. See the GNU General Public License - for more details. - - - - You should have received a copy of the GNU General Public - License along with this program; if not, write to the Free - Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, - MA 02111-1307 USA - - - - - - - - - - Preface - - This document describes how to write an - - ALSA (Advanced Linux Sound Architecture) - driver. The document focuses mainly on PCI soundcards. - In the case of other device types, the API might - be different, too. However, at least the ALSA kernel API is - consistent, and therefore it would be still a bit help for - writing them. - - - - This document targets people who already have enough - C language skills and have basic linux kernel programming - knowledge. This document doesn't explain the general - topic of linux kernel coding and doesn't cover low-level - driver implementation details. It only describes - the standard way to write a PCI sound driver on ALSA. - - - - If you are already familiar with the older ALSA ver.0.5.x API, you - can check the drivers such as sound/pci/es1938.c or - sound/pci/maestro3.c which have also almost the same - code-base in the ALSA 0.5.x tree, so you can compare the differences. - - - - This document is still a draft version. Any feedback and - corrections, please!! - - - - - - - - - File Tree Structure - -
- General - - The ALSA drivers are provided in two ways. - - - - One is the trees provided as a tarball or via cvs from the - ALSA's ftp site, and another is the 2.6 (or later) Linux kernel - tree. To synchronize both, the ALSA driver tree is split into - two different trees: alsa-kernel and alsa-driver. The former - contains purely the source code for the Linux 2.6 (or later) - tree. This tree is designed only for compilation on 2.6 or - later environment. The latter, alsa-driver, contains many subtle - files for compiling ALSA drivers outside of the Linux kernel tree, - wrapper functions for older 2.2 and 2.4 kernels, to adapt the latest kernel API, - and additional drivers which are still in development or in - tests. The drivers in alsa-driver tree will be moved to - alsa-kernel (and eventually to the 2.6 kernel tree) when they are - finished and confirmed to work fine. - - - - The file tree structure of ALSA driver is depicted below. Both - alsa-kernel and alsa-driver have almost the same file - structure, except for core directory. It's - named as acore in alsa-driver tree. - - - ALSA File Tree Structure - - sound - /core - /oss - /seq - /oss - /instr - /ioctl32 - /include - /drivers - /mpu401 - /opl3 - /i2c - /l3 - /synth - /emux - /pci - /(cards) - /isa - /(cards) - /arm - /ppc - /sparc - /usb - /pcmcia /(cards) - /oss - - - -
- -
- core directory - - This directory contains the middle layer which is the heart - of ALSA drivers. In this directory, the native ALSA modules are - stored. The sub-directories contain different modules and are - dependent upon the kernel config. - - -
- core/oss - - - The codes for PCM and mixer OSS emulation modules are stored - in this directory. The rawmidi OSS emulation is included in - the ALSA rawmidi code since it's quite small. The sequencer - code is stored in core/seq/oss directory (see - - below). - -
- -
- core/ioctl32 - - - This directory contains the 32bit-ioctl wrappers for 64bit - architectures such like x86-64, ppc64 and sparc64. For 32bit - and alpha architectures, these are not compiled. - -
- -
- core/seq - - This directory and its sub-directories are for the ALSA - sequencer. This directory contains the sequencer core and - primary sequencer modules such like snd-seq-midi, - snd-seq-virmidi, etc. They are compiled only when - CONFIG_SND_SEQUENCER is set in the kernel - config. - -
- -
- core/seq/oss - - This contains the OSS sequencer emulation codes. - -
- -
- core/seq/instr - - This directory contains the modules for the sequencer - instrument layer. - -
-
- -
- include directory - - This is the place for the public header files of ALSA drivers, - which are to be exported to user-space, or included by - several files at different directories. Basically, the private - header files should not be placed in this directory, but you may - still find files there, due to historical reasons :) - -
- -
- drivers directory - - This directory contains code shared among different drivers - on different architectures. They are hence supposed not to be - architecture-specific. - For example, the dummy pcm driver and the serial MIDI - driver are found in this directory. In the sub-directories, - there is code for components which are independent from - bus and cpu architectures. - - -
- drivers/mpu401 - - The MPU401 and MPU401-UART modules are stored here. - -
- -
- drivers/opl3 and opl4 - - The OPL3 and OPL4 FM-synth stuff is found here. - -
-
- -
- i2c directory - - This contains the ALSA i2c components. - - - - Although there is a standard i2c layer on Linux, ALSA has its - own i2c code for some cards, because the soundcard needs only a - simple operation and the standard i2c API is too complicated for - such a purpose. - - -
- i2c/l3 - - This is a sub-directory for ARM L3 i2c. - -
-
- -
- synth directory - - This contains the synth middle-level modules. - - - - So far, there is only Emu8000/Emu10k1 synth driver under - the synth/emux sub-directory. - -
- -
- pci directory - - This directory and its sub-directories hold the top-level card modules - for PCI soundcards and the code specific to the PCI BUS. - - - - The drivers compiled from a single file are stored directly - in the pci directory, while the drivers with several source files are - stored on their own sub-directory (e.g. emu10k1, ice1712). - -
- -
- isa directory - - This directory and its sub-directories hold the top-level card modules - for ISA soundcards. - -
- -
- arm, ppc, and sparc directories - - They are used for top-level card modules which are - specific to one of these architectures. - -
- -
- usb directory - - This directory contains the USB-audio driver. In the latest version, the - USB MIDI driver is integrated in the usb-audio driver. - -
- -
- pcmcia directory - - The PCMCIA, especially PCCard drivers will go here. CardBus - drivers will be in the pci directory, because their API is identical - to that of standard PCI cards. - -
- -
- oss directory - - The OSS/Lite source files are stored here in Linux 2.6 (or - later) tree. In the ALSA driver tarball, this directory is empty, - of course :) - -
- - - - - - - - Basic Flow for PCI Drivers - -
- Outline - - The minimum flow for PCI soundcards is as follows: - - - define the PCI ID table (see the section - PCI Entries - ). - create probe() callback. - create remove() callback. - create a pci_driver structure - containing the three pointers above. - create an init() function just calling - the pci_register_driver() to register the pci_driver table - defined above. - create an exit() function to call - the pci_unregister_driver() function. - - -
- -
- Full Code Example - - The code example is shown below. Some parts are kept - unimplemented at this moment but will be filled in the - next sections. The numbers in the comment lines of the - snd_mychip_probe() function - refer to details explained in the following section. - - - Basic Flow for PCI Drivers - Example - - - #include - #include - #include - #include - - /* module parameters (see "Module Parameters") */ - /* SNDRV_CARDS: maximum number of cards supported by this module */ - static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX; - static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR; - static int enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE_PNP; - - /* definition of the chip-specific record */ - struct mychip { - struct snd_card *card; - /* the rest of the implementation will be in section - * "PCI Resource Management" - */ - }; - - /* chip-specific destructor - * (see "PCI Resource Management") - */ - static int snd_mychip_free(struct mychip *chip) - { - .... /* will be implemented later... */ - } - - /* component-destructor - * (see "Management of Cards and Components") - */ - static int snd_mychip_dev_free(struct snd_device *device) - { - return snd_mychip_free(device->device_data); - } - - /* chip-specific constructor - * (see "Management of Cards and Components") - */ - static int __devinit snd_mychip_create(struct snd_card *card, - struct pci_dev *pci, - struct mychip **rchip) - { - struct mychip *chip; - int err; - static struct snd_device_ops ops = { - .dev_free = snd_mychip_dev_free, - }; - - *rchip = NULL; - - /* check PCI availability here - * (see "PCI Resource Management") - */ - .... - - /* allocate a chip-specific data with zero filled */ - chip = kzalloc(sizeof(*chip), GFP_KERNEL); - if (chip == NULL) - return -ENOMEM; - - chip->card = card; - - /* rest of initialization here; will be implemented - * later, see "PCI Resource Management" - */ - .... - - err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops); - if (err < 0) { - snd_mychip_free(chip); - return err; - } - - snd_card_set_dev(card, &pci->dev); - - *rchip = chip; - return 0; - } - - /* constructor -- see "Constructor" sub-section */ - static int __devinit snd_mychip_probe(struct pci_dev *pci, - const struct pci_device_id *pci_id) - { - static int dev; - struct snd_card *card; - struct mychip *chip; - int err; - - /* (1) */ - if (dev >= SNDRV_CARDS) - return -ENODEV; - if (!enable[dev]) { - dev++; - return -ENOENT; - } - - /* (2) */ - err = snd_card_create(index[dev], id[dev], THIS_MODULE, 0, &card); - if (err < 0) - return err; - - /* (3) */ - err = snd_mychip_create(card, pci, &chip); - if (err < 0) { - snd_card_free(card); - return err; - } - - /* (4) */ - strcpy(card->driver, "My Chip"); - strcpy(card->shortname, "My Own Chip 123"); - sprintf(card->longname, "%s at 0x%lx irq %i", - card->shortname, chip->ioport, chip->irq); - - /* (5) */ - .... /* implemented later */ - - /* (6) */ - err = snd_card_register(card); - if (err < 0) { - snd_card_free(card); - return err; - } - - /* (7) */ - pci_set_drvdata(pci, card); - dev++; - return 0; - } - - /* destructor -- see the "Destructor" sub-section */ - static void __devexit snd_mychip_remove(struct pci_dev *pci) - { - snd_card_free(pci_get_drvdata(pci)); - pci_set_drvdata(pci, NULL); - } -]]> - - - -
- -
- Constructor - - The real constructor of PCI drivers is the probe callback. - The probe callback and other component-constructors which are called - from the probe callback should be defined with - the __devinit prefix. You - cannot use the __init prefix for them, - because any PCI device could be a hotplug device. - - - - In the probe callback, the following scheme is often used. - - -
- 1) Check and increment the device index. - - - -= SNDRV_CARDS) - return -ENODEV; - if (!enable[dev]) { - dev++; - return -ENOENT; - } -]]> - - - - where enable[dev] is the module option. - - - - Each time the probe callback is called, check the - availability of the device. If not available, simply increment - the device index and returns. dev will be incremented also - later (step - 7). - -
- -
- 2) Create a card instance - - - - - - - - - - The details will be explained in the section - - Management of Cards and Components. - -
- -
- 3) Create a main component - - In this part, the PCI resources are allocated. - - - - - - - - The details will be explained in the section PCI Resource - Management. - -
- -
- 4) Set the driver ID and name strings. - - - -driver, "My Chip"); - strcpy(card->shortname, "My Own Chip 123"); - sprintf(card->longname, "%s at 0x%lx irq %i", - card->shortname, chip->ioport, chip->irq); -]]> - - - - The driver field holds the minimal ID string of the - chip. This is used by alsa-lib's configurator, so keep it - simple but unique. - Even the same driver can have different driver IDs to - distinguish the functionality of each chip type. - - - - The shortname field is a string shown as more verbose - name. The longname field contains the information - shown in /proc/asound/cards. - -
- -
- 5) Create other components, such as mixer, MIDI, etc. - - Here you define the basic components such as - PCM, - mixer (e.g. AC97), - MIDI (e.g. MPU-401), - and other interfaces. - Also, if you want a proc - file, define it here, too. - -
- -
- 6) Register the card instance. - - - - - - - - - - Will be explained in the section Management - of Cards and Components, too. - -
- -
- 7) Set the PCI driver data and return zero. - - - - - - - - In the above, the card record is stored. This pointer is - used in the remove callback and power-management - callbacks, too. - -
-
- -
- Destructor - - The destructor, remove callback, simply releases the card - instance. Then the ALSA middle layer will release all the - attached components automatically. - - - - It would be typically like the following: - - - - - - - - The above code assumes that the card pointer is set to the PCI - driver data. - -
- -
- Header Files - - For the above example, at least the following include files - are necessary. - - - - - #include - #include - #include - #include -]]> - - - - where the last one is necessary only when module options are - defined in the source file. If the code is split into several - files, the files without module options don't need them. - - - - In addition to these headers, you'll need - <linux/interrupt.h> for interrupt - handling, and <asm/io.h> for I/O - access. If you use the mdelay() or - udelay() functions, you'll need to include - <linux/delay.h> too. - - - - The ALSA interfaces like the PCM and control APIs are defined in other - <sound/xxx.h> header files. - They have to be included after - <sound/core.h>. - - -
- - - - - - - - Management of Cards and Components - -
- Card Instance - - For each soundcard, a card record must be allocated. - - - - A card record is the headquarters of the soundcard. It manages - the whole list of devices (components) on the soundcard, such as - PCM, mixers, MIDI, synthesizer, and so on. Also, the card - record holds the ID and the name strings of the card, manages - the root of proc files, and controls the power-management states - and hotplug disconnections. The component list on the card - record is used to manage the correct release of resources at - destruction. - - - - As mentioned above, to create a card instance, call - snd_card_create(). - - - - - - - - - - The function takes five arguments, the card-index number, the - id string, the module pointer (usually - THIS_MODULE), - the size of extra-data space, and the pointer to return the - card instance. The extra_size argument is used to - allocate card->private_data for the - chip-specific data. Note that these data - are allocated by snd_card_create(). - -
- -
- Components - - After the card is created, you can attach the components - (devices) to the card instance. In an ALSA driver, a component is - represented as a struct snd_device object. - A component can be a PCM instance, a control interface, a raw - MIDI interface, etc. Each such instance has one component - entry. - - - - A component can be created via - snd_device_new() function. - - - - - - - - - - This takes the card pointer, the device-level - (SNDRV_DEV_XXX), the data pointer, and the - callback pointers (&ops). The - device-level defines the type of components and the order of - registration and de-registration. For most components, the - device-level is already defined. For a user-defined component, - you can use SNDRV_DEV_LOWLEVEL. - - - - This function itself doesn't allocate the data space. The data - must be allocated manually beforehand, and its pointer is passed - as the argument. This pointer is used as the - (chip identifier in the above example) - for the instance. - - - - Each pre-defined ALSA component such as ac97 and pcm calls - snd_device_new() inside its - constructor. The destructor for each component is defined in the - callback pointers. Hence, you don't need to take care of - calling a destructor for such a component. - - - - If you wish to create your own component, you need to - set the destructor function to the dev_free callback in - the ops, so that it can be released - automatically via snd_card_free(). - The next example will show an implementation of chip-specific - data. - -
- -
- Chip-Specific Data - - Chip-specific information, e.g. the I/O port address, its - resource pointer, or the irq number, is stored in the - chip-specific record. - - - - - - - - - - In general, there are two ways of allocating the chip record. - - -
- 1. Allocating via <function>snd_card_create()</function>. - - As mentioned above, you can pass the extra-data-length - to the 4th argument of snd_card_create(), i.e. - - - - - - - - struct mychip is the type of the chip record. - - - - In return, the allocated record can be accessed as - - - -private_data; -]]> - - - - With this method, you don't have to allocate twice. - The record is released together with the card instance. - -
- -
- 2. Allocating an extra device. - - - After allocating a card instance via - snd_card_create() (with - 0 on the 4th arg), call - kzalloc(). - - - - - - - - - - The chip record should have the field to hold the card - pointer at least, - - - - - - - - - - Then, set the card pointer in the returned chip instance. - - - -card = card; -]]> - - - - - - Next, initialize the fields, and register this chip - record as a low-level device with a specified - ops, - - - - - - - - snd_mychip_dev_free() is the - device-destructor function, which will call the real - destructor. - - - - - -device_data); - } -]]> - - - - where snd_mychip_free() is the real destructor. - -
-
- -
- Registration and Release - - After all components are assigned, register the card instance - by calling snd_card_register(). Access - to the device files is enabled at this point. That is, before - snd_card_register() is called, the - components are safely inaccessible from external side. If this - call fails, exit the probe function after releasing the card via - snd_card_free(). - - - - For releasing the card instance, you can call simply - snd_card_free(). As mentioned earlier, all - components are released automatically by this call. - - - - As further notes, the destructors (both - snd_mychip_dev_free and - snd_mychip_free) cannot be defined with - the __devexit prefix, because they may be - called from the constructor, too, at the false path. - - - - For a device which allows hotplugging, you can use - snd_card_free_when_closed. This one will - postpone the destruction until all devices are closed. - - -
- - - - - - - - - PCI Resource Management - -
- Full Code Example - - In this section, we'll complete the chip-specific constructor, - destructor and PCI entries. Example code is shown first, - below. - - - PCI Resource Management Example - -irq >= 0) - free_irq(chip->irq, chip); - /* release the I/O ports & memory */ - pci_release_regions(chip->pci); - /* disable the PCI entry */ - pci_disable_device(chip->pci); - /* release the data */ - kfree(chip); - return 0; - } - - /* chip-specific constructor */ - static int __devinit snd_mychip_create(struct snd_card *card, - struct pci_dev *pci, - struct mychip **rchip) - { - struct mychip *chip; - int err; - static struct snd_device_ops ops = { - .dev_free = snd_mychip_dev_free, - }; - - *rchip = NULL; - - /* initialize the PCI entry */ - err = pci_enable_device(pci); - if (err < 0) - return err; - /* check PCI availability (28bit DMA) */ - if (pci_set_dma_mask(pci, DMA_28BIT_MASK) < 0 || - pci_set_consistent_dma_mask(pci, DMA_28BIT_MASK) < 0) { - printk(KERN_ERR "error to set 28bit mask DMA\n"); - pci_disable_device(pci); - return -ENXIO; - } - - chip = kzalloc(sizeof(*chip), GFP_KERNEL); - if (chip == NULL) { - pci_disable_device(pci); - return -ENOMEM; - } - - /* initialize the stuff */ - chip->card = card; - chip->pci = pci; - chip->irq = -1; - - /* (1) PCI resource allocation */ - err = pci_request_regions(pci, "My Chip"); - if (err < 0) { - kfree(chip); - pci_disable_device(pci); - return err; - } - chip->port = pci_resource_start(pci, 0); - if (request_irq(pci->irq, snd_mychip_interrupt, - IRQF_SHARED, "My Chip", chip)) { - printk(KERN_ERR "cannot grab irq %d\n", pci->irq); - snd_mychip_free(chip); - return -EBUSY; - } - chip->irq = pci->irq; - - /* (2) initialization of the chip hardware */ - .... /* (not implemented in this document) */ - - err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops); - if (err < 0) { - snd_mychip_free(chip); - return err; - } - - snd_card_set_dev(card, &pci->dev); - - *rchip = chip; - return 0; - } - - /* PCI IDs */ - static struct pci_device_id snd_mychip_ids[] = { - { PCI_VENDOR_ID_FOO, PCI_DEVICE_ID_BAR, - PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, }, - .... - { 0, } - }; - MODULE_DEVICE_TABLE(pci, snd_mychip_ids); - - /* pci_driver definition */ - static struct pci_driver driver = { - .name = "My Own Chip", - .id_table = snd_mychip_ids, - .probe = snd_mychip_probe, - .remove = __devexit_p(snd_mychip_remove), - }; - - /* module initialization */ - static int __init alsa_card_mychip_init(void) - { - return pci_register_driver(&driver); - } - - /* module clean up */ - static void __exit alsa_card_mychip_exit(void) - { - pci_unregister_driver(&driver); - } - - module_init(alsa_card_mychip_init) - module_exit(alsa_card_mychip_exit) - - EXPORT_NO_SYMBOLS; /* for old kernels only */ -]]> - - - -
- -
- Some Hafta's - - The allocation of PCI resources is done in the - probe() function, and usually an extra - xxx_create() function is written for this - purpose. - - - - In the case of PCI devices, you first have to call - the pci_enable_device() function before - allocating resources. Also, you need to set the proper PCI DMA - mask to limit the accessed I/O range. In some cases, you might - need to call pci_set_master() function, - too. - - - - Suppose the 28bit mask, and the code to be added would be like: - - - - - - - -
- -
- Resource Allocation - - The allocation of I/O ports and irqs is done via standard kernel - functions. Unlike ALSA ver.0.5.x., there are no helpers for - that. And these resources must be released in the destructor - function (see below). Also, on ALSA 0.9.x, you don't need to - allocate (pseudo-)DMA for PCI like in ALSA 0.5.x. - - - - Now assume that the PCI device has an I/O port with 8 bytes - and an interrupt. Then struct mychip will have the - following fields: - - - - - - - - - - For an I/O port (and also a memory region), you need to have - the resource pointer for the standard resource management. For - an irq, you have to keep only the irq number (integer). But you - need to initialize this number as -1 before actual allocation, - since irq 0 is valid. The port address and its resource pointer - can be initialized as null by - kzalloc() automatically, so you - don't have to take care of resetting them. - - - - The allocation of an I/O port is done like this: - - - -port = pci_resource_start(pci, 0); -]]> - - - - - - - It will reserve the I/O port region of 8 bytes of the given - PCI device. The returned value, chip->res_port, is allocated - via kmalloc() by - request_region(). The pointer must be - released via kfree(), but there is a - problem with this. This issue will be explained later. - - - - The allocation of an interrupt source is done like this: - - - -irq, snd_mychip_interrupt, - IRQF_SHARED, "My Chip", chip)) { - printk(KERN_ERR "cannot grab irq %d\n", pci->irq); - snd_mychip_free(chip); - return -EBUSY; - } - chip->irq = pci->irq; -]]> - - - - where snd_mychip_interrupt() is the - interrupt handler defined later. - Note that chip->irq should be defined - only when request_irq() succeeded. - - - - On the PCI bus, interrupts can be shared. Thus, - IRQF_SHARED is used as the interrupt flag of - request_irq(). - - - - The last argument of request_irq() is the - data pointer passed to the interrupt handler. Usually, the - chip-specific record is used for that, but you can use what you - like, too. - - - - I won't give details about the interrupt handler at this - point, but at least its appearance can be explained now. The - interrupt handler looks usually like the following: - - - - - - - - - - Now let's write the corresponding destructor for the resources - above. The role of destructor is simple: disable the hardware - (if already activated) and release the resources. So far, we - have no hardware part, so the disabling code is not written here. - - - - To release the resources, the check-and-release - method is a safer way. For the interrupt, do like this: - - - -irq >= 0) - free_irq(chip->irq, chip); -]]> - - - - Since the irq number can start from 0, you should initialize - chip->irq with a negative value (e.g. -1), so that you can - check the validity of the irq number as above. - - - - When you requested I/O ports or memory regions via - pci_request_region() or - pci_request_regions() like in this example, - release the resource(s) using the corresponding function, - pci_release_region() or - pci_release_regions(). - - - -pci); -]]> - - - - - - When you requested manually via request_region() - or request_mem_region, you can release it via - release_resource(). Suppose that you keep - the resource pointer returned from request_region() - in chip->res_port, the release procedure looks like: - - - -res_port); -]]> - - - - - - Don't forget to call pci_disable_device() - before the end. - - - - And finally, release the chip-specific record. - - - - - - - - - - Again, remember that you cannot - use the __devexit prefix for this destructor. - - - - We didn't implement the hardware disabling part in the above. - If you need to do this, please note that the destructor may be - called even before the initialization of the chip is completed. - It would be better to have a flag to skip hardware disabling - if the hardware was not initialized yet. - - - - When the chip-data is assigned to the card using - snd_device_new() with - SNDRV_DEV_LOWLELVEL , its destructor is - called at the last. That is, it is assured that all other - components like PCMs and controls have already been released. - You don't have to stop PCMs, etc. explicitly, but just - call low-level hardware stopping. - - - - The management of a memory-mapped region is almost as same as - the management of an I/O port. You'll need three fields like - the following: - - - - - - - - and the allocation would be like below: - - - -iobase_phys = pci_resource_start(pci, 0); - chip->iobase_virt = ioremap_nocache(chip->iobase_phys, - pci_resource_len(pci, 0)); -]]> - - - - and the corresponding destructor would be: - - - -iobase_virt) - iounmap(chip->iobase_virt); - .... - pci_release_regions(chip->pci); - .... - } -]]> - - - - -
- -
- Registration of Device Struct - - At some point, typically after calling snd_device_new(), - you need to register the struct device of the chip - you're handling for udev and co. ALSA provides a macro for compatibility with - older kernels. Simply call like the following: - - -dev); -]]> - - - so that it stores the PCI's device pointer to the card. This will be - referred by ALSA core functions later when the devices are registered. - - - In the case of non-PCI, pass the proper device struct pointer of the BUS - instead. (In the case of legacy ISA without PnP, you don't have to do - anything.) - -
- -
- PCI Entries - - So far, so good. Let's finish the missing PCI - stuff. At first, we need a - pci_device_id table for this - chipset. It's a table of PCI vendor/device ID number, and some - masks. - - - - For example, - - - - - - - - - - The first and second fields of - the pci_device_id structure are the vendor and - device IDs. If you have no reason to filter the matching - devices, you can leave the remaining fields as above. The last - field of the pci_device_id struct contains - private data for this entry. You can specify any value here, for - example, to define specific operations for supported device IDs. - Such an example is found in the intel8x0 driver. - - - - The last entry of this list is the terminator. You must - specify this all-zero entry. - - - - Then, prepare the pci_driver record: - - - - - - - - - - The probe and - remove functions have already - been defined in the previous sections. - The remove function should - be defined with the - __devexit_p() macro, so that it's not - defined for built-in (and non-hot-pluggable) case. The - name - field is the name string of this device. Note that you must not - use a slash / in this string. - - - - And at last, the module entries: - - - - - - - - - - Note that these module entries are tagged with - __init and - __exit prefixes, not - __devinit nor - __devexit. - - - - Oh, one thing was forgotten. If you have no exported symbols, - you need to declare it in 2.2 or 2.4 kernels (it's not necessary in 2.6 kernels). - - - - - - - - That's all! - -
- - - - - - - - PCM Interface - -
- General - - The PCM middle layer of ALSA is quite powerful and it is only - necessary for each driver to implement the low-level functions - to access its hardware. - - - - For accessing to the PCM layer, you need to include - <sound/pcm.h> first. In addition, - <sound/pcm_params.h> might be needed - if you access to some functions related with hw_param. - - - - Each card device can have up to four pcm instances. A pcm - instance corresponds to a pcm device file. The limitation of - number of instances comes only from the available bit size of - the Linux's device numbers. Once when 64bit device number is - used, we'll have more pcm instances available. - - - - A pcm instance consists of pcm playback and capture streams, - and each pcm stream consists of one or more pcm substreams. Some - soundcards support multiple playback functions. For example, - emu10k1 has a PCM playback of 32 stereo substreams. In this case, at - each open, a free substream is (usually) automatically chosen - and opened. Meanwhile, when only one substream exists and it was - already opened, the successful open will either block - or error with EAGAIN according to the - file open mode. But you don't have to care about such details in your - driver. The PCM middle layer will take care of such work. - -
- -
- Full Code Example - - The example code below does not include any hardware access - routines but shows only the skeleton, how to build up the PCM - interfaces. - - - PCM Example Code - - - .... - - /* hardware definition */ - static struct snd_pcm_hardware snd_mychip_playback_hw = { - .info = (SNDRV_PCM_INFO_MMAP | - SNDRV_PCM_INFO_INTERLEAVED | - SNDRV_PCM_INFO_BLOCK_TRANSFER | - SNDRV_PCM_INFO_MMAP_VALID), - .formats = SNDRV_PCM_FMTBIT_S16_LE, - .rates = SNDRV_PCM_RATE_8000_48000, - .rate_min = 8000, - .rate_max = 48000, - .channels_min = 2, - .channels_max = 2, - .buffer_bytes_max = 32768, - .period_bytes_min = 4096, - .period_bytes_max = 32768, - .periods_min = 1, - .periods_max = 1024, - }; - - /* hardware definition */ - static struct snd_pcm_hardware snd_mychip_capture_hw = { - .info = (SNDRV_PCM_INFO_MMAP | - SNDRV_PCM_INFO_INTERLEAVED | - SNDRV_PCM_INFO_BLOCK_TRANSFER | - SNDRV_PCM_INFO_MMAP_VALID), - .formats = SNDRV_PCM_FMTBIT_S16_LE, - .rates = SNDRV_PCM_RATE_8000_48000, - .rate_min = 8000, - .rate_max = 48000, - .channels_min = 2, - .channels_max = 2, - .buffer_bytes_max = 32768, - .period_bytes_min = 4096, - .period_bytes_max = 32768, - .periods_min = 1, - .periods_max = 1024, - }; - - /* open callback */ - static int snd_mychip_playback_open(struct snd_pcm_substream *substream) - { - struct mychip *chip = snd_pcm_substream_chip(substream); - struct snd_pcm_runtime *runtime = substream->runtime; - - runtime->hw = snd_mychip_playback_hw; - /* more hardware-initialization will be done here */ - .... - return 0; - } - - /* close callback */ - static int snd_mychip_playback_close(struct snd_pcm_substream *substream) - { - struct mychip *chip = snd_pcm_substream_chip(substream); - /* the hardware-specific codes will be here */ - .... - return 0; - - } - - /* open callback */ - static int snd_mychip_capture_open(struct snd_pcm_substream *substream) - { - struct mychip *chip = snd_pcm_substream_chip(substream); - struct snd_pcm_runtime *runtime = substream->runtime; - - runtime->hw = snd_mychip_capture_hw; - /* more hardware-initialization will be done here */ - .... - return 0; - } - - /* close callback */ - static int snd_mychip_capture_close(struct snd_pcm_substream *substream) - { - struct mychip *chip = snd_pcm_substream_chip(substream); - /* the hardware-specific codes will be here */ - .... - return 0; - - } - - /* hw_params callback */ - static int snd_mychip_pcm_hw_params(struct snd_pcm_substream *substream, - struct snd_pcm_hw_params *hw_params) - { - return snd_pcm_lib_malloc_pages(substream, - params_buffer_bytes(hw_params)); - } - - /* hw_free callback */ - static int snd_mychip_pcm_hw_free(struct snd_pcm_substream *substream) - { - return snd_pcm_lib_free_pages(substream); - } - - /* prepare callback */ - static int snd_mychip_pcm_prepare(struct snd_pcm_substream *substream) - { - struct mychip *chip = snd_pcm_substream_chip(substream); - struct snd_pcm_runtime *runtime = substream->runtime; - - /* set up the hardware with the current configuration - * for example... - */ - mychip_set_sample_format(chip, runtime->format); - mychip_set_sample_rate(chip, runtime->rate); - mychip_set_channels(chip, runtime->channels); - mychip_set_dma_setup(chip, runtime->dma_addr, - chip->buffer_size, - chip->period_size); - return 0; - } - - /* trigger callback */ - static int snd_mychip_pcm_trigger(struct snd_pcm_substream *substream, - int cmd) - { - switch (cmd) { - case SNDRV_PCM_TRIGGER_START: - /* do something to start the PCM engine */ - .... - break; - case SNDRV_PCM_TRIGGER_STOP: - /* do something to stop the PCM engine */ - .... - break; - default: - return -EINVAL; - } - } - - /* pointer callback */ - static snd_pcm_uframes_t - snd_mychip_pcm_pointer(struct snd_pcm_substream *substream) - { - struct mychip *chip = snd_pcm_substream_chip(substream); - unsigned int current_ptr; - - /* get the current hardware pointer */ - current_ptr = mychip_get_hw_pointer(chip); - return current_ptr; - } - - /* operators */ - static struct snd_pcm_ops snd_mychip_playback_ops = { - .open = snd_mychip_playback_open, - .close = snd_mychip_playback_close, - .ioctl = snd_pcm_lib_ioctl, - .hw_params = snd_mychip_pcm_hw_params, - .hw_free = snd_mychip_pcm_hw_free, - .prepare = snd_mychip_pcm_prepare, - .trigger = snd_mychip_pcm_trigger, - .pointer = snd_mychip_pcm_pointer, - }; - - /* operators */ - static struct snd_pcm_ops snd_mychip_capture_ops = { - .open = snd_mychip_capture_open, - .close = snd_mychip_capture_close, - .ioctl = snd_pcm_lib_ioctl, - .hw_params = snd_mychip_pcm_hw_params, - .hw_free = snd_mychip_pcm_hw_free, - .prepare = snd_mychip_pcm_prepare, - .trigger = snd_mychip_pcm_trigger, - .pointer = snd_mychip_pcm_pointer, - }; - - /* - * definitions of capture are omitted here... - */ - - /* create a pcm device */ - static int __devinit snd_mychip_new_pcm(struct mychip *chip) - { - struct snd_pcm *pcm; - int err; - - err = snd_pcm_new(chip->card, "My Chip", 0, 1, 1, &pcm); - if (err < 0) - return err; - pcm->private_data = chip; - strcpy(pcm->name, "My Chip"); - chip->pcm = pcm; - /* set operators */ - snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, - &snd_mychip_playback_ops); - snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, - &snd_mychip_capture_ops); - /* pre-allocation of buffers */ - /* NOTE: this may fail */ - snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV, - snd_dma_pci_data(chip->pci), - 64*1024, 64*1024); - return 0; - } -]]> - - - -
- -
- Constructor - - A pcm instance is allocated by the snd_pcm_new() - function. It would be better to create a constructor for pcm, - namely, - - - -card, "My Chip", 0, 1, 1, &pcm); - if (err < 0) - return err; - pcm->private_data = chip; - strcpy(pcm->name, "My Chip"); - chip->pcm = pcm; - .... - return 0; - } -]]> - - - - - - The snd_pcm_new() function takes four - arguments. The first argument is the card pointer to which this - pcm is assigned, and the second is the ID string. - - - - The third argument (index, 0 in the - above) is the index of this new pcm. It begins from zero. If - you create more than one pcm instances, specify the - different numbers in this argument. For example, - index = 1 for the second PCM device. - - - - The fourth and fifth arguments are the number of substreams - for playback and capture, respectively. Here 1 is used for - both arguments. When no playback or capture substreams are available, - pass 0 to the corresponding argument. - - - - If a chip supports multiple playbacks or captures, you can - specify more numbers, but they must be handled properly in - open/close, etc. callbacks. When you need to know which - substream you are referring to, then it can be obtained from - struct snd_pcm_substream data passed to each callback - as follows: - - - -number; -]]> - - - - - - After the pcm is created, you need to set operators for each - pcm stream. - - - - - - - - - - The operators are defined typically like this: - - - - - - - - All the callbacks are described in the - - Operators subsection. - - - - After setting the operators, you probably will want to - pre-allocate the buffer. For the pre-allocation, simply call - the following: - - - -pci), - 64*1024, 64*1024); -]]> - - - - It will allocate a buffer up to 64kB as default. - Buffer management details will be described in the later section Buffer and Memory - Management. - - - - Additionally, you can set some extra information for this pcm - in pcm->info_flags. - The available values are defined as - SNDRV_PCM_INFO_XXX in - <sound/asound.h>, which is used for - the hardware definition (described later). When your soundchip - supports only half-duplex, specify like this: - - - -info_flags = SNDRV_PCM_INFO_HALF_DUPLEX; -]]> - - - -
- -
- ... And the Destructor? - - The destructor for a pcm instance is not always - necessary. Since the pcm device will be released by the middle - layer code automatically, you don't have to call the destructor - explicitly. - - - - The destructor would be necessary if you created - special records internally and needed to release them. In such a - case, set the destructor function to - pcm->private_free: - - - PCM Instance with a Destructor - -my_private_pcm_data); - /* do what you like else */ - .... - } - - static int __devinit snd_mychip_new_pcm(struct mychip *chip) - { - struct snd_pcm *pcm; - .... - /* allocate your own data */ - chip->my_private_pcm_data = kmalloc(...); - /* set the destructor */ - pcm->private_data = chip; - pcm->private_free = mychip_pcm_free; - .... - } -]]> - - - -
- -
- Runtime Pointer - The Chest of PCM Information - - When the PCM substream is opened, a PCM runtime instance is - allocated and assigned to the substream. This pointer is - accessible via substream->runtime. - This runtime pointer holds most information you need - to control the PCM: the copy of hw_params and sw_params configurations, the buffer - pointers, mmap records, spinlocks, etc. - - - - The definition of runtime instance is found in - <sound/pcm.h>. Here are - the contents of this file: - - - - - - - - - For the operators (callbacks) of each sound driver, most of - these records are supposed to be read-only. Only the PCM - middle-layer changes / updates them. The exceptions are - the hardware description (hw), interrupt callbacks - (transfer_ack_xxx), DMA buffer information, and the private - data. Besides, if you use the standard buffer allocation - method via snd_pcm_lib_malloc_pages(), - you don't need to set the DMA buffer information by yourself. - - - - In the sections below, important records are explained. - - -
- Hardware Description - - The hardware descriptor (struct snd_pcm_hardware) - contains the definitions of the fundamental hardware - configuration. Above all, you'll need to define this in - - the open callback. - Note that the runtime instance holds the copy of the - descriptor, not the pointer to the existing descriptor. That - is, in the open callback, you can modify the copied descriptor - (runtime->hw) as you need. For example, if the maximum - number of channels is 1 only on some chip models, you can - still use the same hardware descriptor and change the - channels_max later: - - -runtime; - ... - runtime->hw = snd_mychip_playback_hw; /* common definition */ - if (chip->model == VERY_OLD_ONE) - runtime->hw.channels_max = 1; -]]> - - - - - - Typically, you'll have a hardware descriptor as below: - - - - - - - - - - - The info field contains the type and - capabilities of this pcm. The bit flags are defined in - <sound/asound.h> as - SNDRV_PCM_INFO_XXX. Here, at least, you - have to specify whether the mmap is supported and which - interleaved format is supported. - When the is supported, add the - SNDRV_PCM_INFO_MMAP flag here. When the - hardware supports the interleaved or the non-interleaved - formats, SNDRV_PCM_INFO_INTERLEAVED or - SNDRV_PCM_INFO_NONINTERLEAVED flag must - be set, respectively. If both are supported, you can set both, - too. - - - - In the above example, MMAP_VALID and - BLOCK_TRANSFER are specified for the OSS mmap - mode. Usually both are set. Of course, - MMAP_VALID is set only if the mmap is - really supported. - - - - The other possible flags are - SNDRV_PCM_INFO_PAUSE and - SNDRV_PCM_INFO_RESUME. The - PAUSE bit means that the pcm supports the - pause operation, while the - RESUME bit means that the pcm supports - the full suspend/resume operation. - If the PAUSE flag is set, - the trigger callback below - must handle the corresponding (pause push/release) commands. - The suspend/resume trigger commands can be defined even without - the RESUME flag. See - Power Management section for details. - - - - When the PCM substreams can be synchronized (typically, - synchronized start/stop of a playback and a capture streams), - you can give SNDRV_PCM_INFO_SYNC_START, - too. In this case, you'll need to check the linked-list of - PCM substreams in the trigger callback. This will be - described in the later section. - - - - - - formats field contains the bit-flags - of supported formats (SNDRV_PCM_FMTBIT_XXX). - If the hardware supports more than one format, give all or'ed - bits. In the example above, the signed 16bit little-endian - format is specified. - - - - - - rates field contains the bit-flags of - supported rates (SNDRV_PCM_RATE_XXX). - When the chip supports continuous rates, pass - CONTINUOUS bit additionally. - The pre-defined rate bits are provided only for typical - rates. If your chip supports unconventional rates, you need to add - the KNOT bit and set up the hardware - constraint manually (explained later). - - - - - - rate_min and - rate_max define the minimum and - maximum sample rate. This should correspond somehow to - rates bits. - - - - - - channel_min and - channel_max - define, as you might already expected, the minimum and maximum - number of channels. - - - - - - buffer_bytes_max defines the - maximum buffer size in bytes. There is no - buffer_bytes_min field, since - it can be calculated from the minimum period size and the - minimum number of periods. - Meanwhile, period_bytes_min and - define the minimum and maximum size of the period in bytes. - periods_max and - periods_min define the maximum and - minimum number of periods in the buffer. - - - - The period is a term that corresponds to - a fragment in the OSS world. The period defines the size at - which a PCM interrupt is generated. This size strongly - depends on the hardware. - Generally, the smaller period size will give you more - interrupts, that is, more controls. - In the case of capture, this size defines the input latency. - On the other hand, the whole buffer size defines the - output latency for the playback direction. - - - - - - There is also a field fifo_size. - This specifies the size of the hardware FIFO, but currently it - is neither used in the driver nor in the alsa-lib. So, you - can ignore this field. - - - - -
- -
- PCM Configurations - - Ok, let's go back again to the PCM runtime records. - The most frequently referred records in the runtime instance are - the PCM configurations. - The PCM configurations are stored in the runtime instance - after the application sends hw_params data via - alsa-lib. There are many fields copied from hw_params and - sw_params structs. For example, - format holds the format type - chosen by the application. This field contains the enum value - SNDRV_PCM_FORMAT_XXX. - - - - One thing to be noted is that the configured buffer and period - sizes are stored in frames in the runtime. - In the ALSA world, 1 frame = channels * samples-size. - For conversion between frames and bytes, you can use the - frames_to_bytes() and - bytes_to_frames() helper functions. - - -period_size); -]]> - - - - - - Also, many software parameters (sw_params) are - stored in frames, too. Please check the type of the field. - snd_pcm_uframes_t is for the frames as unsigned - integer while snd_pcm_sframes_t is for the frames - as signed integer. - -
- -
- DMA Buffer Information - - The DMA buffer is defined by the following four fields, - dma_area, - dma_addr, - dma_bytes and - dma_private. - The dma_area holds the buffer - pointer (the logical address). You can call - memcpy from/to - this pointer. Meanwhile, dma_addr - holds the physical address of the buffer. This field is - specified only when the buffer is a linear buffer. - dma_bytes holds the size of buffer - in bytes. dma_private is used for - the ALSA DMA allocator. - - - - If you use a standard ALSA function, - snd_pcm_lib_malloc_pages(), for - allocating the buffer, these fields are set by the ALSA middle - layer, and you should not change them by - yourself. You can read them but not write them. - On the other hand, if you want to allocate the buffer by - yourself, you'll need to manage it in hw_params callback. - At least, dma_bytes is mandatory. - dma_area is necessary when the - buffer is mmapped. If your driver doesn't support mmap, this - field is not necessary. dma_addr - is also optional. You can use - dma_private as you like, too. - -
- -
- Running Status - - The running status can be referred via runtime->status. - This is the pointer to the struct snd_pcm_mmap_status - record. For example, you can get the current DMA hardware - pointer via runtime->status->hw_ptr. - - - - The DMA application pointer can be referred via - runtime->control, which points to the - struct snd_pcm_mmap_control record. - However, accessing directly to this value is not recommended. - -
- -
- Private Data - - You can allocate a record for the substream and store it in - runtime->private_data. Usually, this - is done in - - the open callback. - Don't mix this with pcm->private_data. - The pcm->private_data usually points to the - chip instance assigned statically at the creation of PCM, while the - runtime->private_data points to a dynamic - data structure created at the PCM open callback. - - - -runtime->private_data = data; - .... - } -]]> - - - - - - The allocated object must be released in - - the close callback. - -
- -
- Interrupt Callbacks - - The field transfer_ack_begin and - transfer_ack_end are called at - the beginning and at the end of - snd_pcm_period_elapsed(), respectively. - -
- -
- -
- Operators - - OK, now let me give details about each pcm callback - (ops). In general, every callback must - return 0 if successful, or a negative error number - such as -EINVAL. To choose an appropriate - error number, it is advised to check what value other parts of - the kernel return when the same kind of request fails. - - - - The callback function takes at least the argument with - snd_pcm_substream pointer. To retrieve - the chip record from the given substream instance, you can use the - following macro. - - - - - - - - The macro reads substream->private_data, - which is a copy of pcm->private_data. - You can override the former if you need to assign different data - records per PCM substream. For example, the cmi8330 driver assigns - different private_data for playback and capture directions, - because it uses two different codecs (SB- and AD-compatible) for - different directions. - - -
- open callback - - - - - - - - This is called when a pcm substream is opened. - - - - At least, here you have to initialize the runtime->hw - record. Typically, this is done by like this: - - - -runtime; - - runtime->hw = snd_mychip_playback_hw; - return 0; - } -]]> - - - - where snd_mychip_playback_hw is the - pre-defined hardware description. - - - - You can allocate a private data in this callback, as described - in - Private Data section. - - - - If the hardware configuration needs more constraints, set the - hardware constraints here, too. - See - Constraints for more details. - -
- -
- close callback - - - - - - - - Obviously, this is called when a pcm substream is closed. - - - - Any private instance for a pcm substream allocated in the - open callback will be released here. - - - -runtime->private_data); - .... - } -]]> - - - -
- -
- ioctl callback - - This is used for any special call to pcm ioctls. But - usually you can pass a generic ioctl callback, - snd_pcm_lib_ioctl. - -
- -
- hw_params callback - - - - - - - - - - This is called when the hardware parameter - (hw_params) is set - up by the application, - that is, once when the buffer size, the period size, the - format, etc. are defined for the pcm substream. - - - - Many hardware setups should be done in this callback, - including the allocation of buffers. - - - - Parameters to be initialized are retrieved by - params_xxx() macros. To allocate - buffer, you can call a helper function, - - - - - - - - snd_pcm_lib_malloc_pages() is available - only when the DMA buffers have been pre-allocated. - See the section - Buffer Types for more details. - - - - Note that this and prepare callbacks - may be called multiple times per initialization. - For example, the OSS emulation may - call these callbacks at each change via its ioctl. - - - - Thus, you need to be careful not to allocate the same buffers - many times, which will lead to memory leaks! Calling the - helper function above many times is OK. It will release the - previous buffer automatically when it was already allocated. - - - - Another note is that this callback is non-atomic - (schedulable). This is important, because the - trigger callback - is atomic (non-schedulable). That is, mutexes or any - schedule-related functions are not available in - trigger callback. - Please see the subsection - - Atomicity for details. - -
- -
- hw_free callback - - - - - - - - - - This is called to release the resources allocated via - hw_params. For example, releasing the - buffer via - snd_pcm_lib_malloc_pages() is done by - calling the following: - - - - - - - - - - This function is always called before the close callback is called. - Also, the callback may be called multiple times, too. - Keep track whether the resource was already released. - -
- -
- prepare callback - - - - - - - - - - This callback is called when the pcm is - prepared. You can set the format type, sample - rate, etc. here. The difference from - hw_params is that the - prepare callback will be called each - time - snd_pcm_prepare() is called, i.e. when - recovering after underruns, etc. - - - - Note that this callback is now non-atomic. - You can use schedule-related functions safely in this callback. - - - - In this and the following callbacks, you can refer to the - values via the runtime record, - substream->runtime. - For example, to get the current - rate, format or channels, access to - runtime->rate, - runtime->format or - runtime->channels, respectively. - The physical address of the allocated buffer is set to - runtime->dma_area. The buffer and period sizes are - in runtime->buffer_size and runtime->period_size, - respectively. - - - - Be careful that this callback will be called many times at - each setup, too. - -
- -
- trigger callback - - - - - - - - This is called when the pcm is started, stopped or paused. - - - - Which action is specified in the second argument, - SNDRV_PCM_TRIGGER_XXX in - <sound/pcm.h>. At least, - the START and STOP - commands must be defined in this callback. - - - - - - - - - - When the pcm supports the pause operation (given in the info - field of the hardware table), the PAUSE_PUSE - and PAUSE_RELEASE commands must be - handled here, too. The former is the command to pause the pcm, - and the latter to restart the pcm again. - - - - When the pcm supports the suspend/resume operation, - regardless of full or partial suspend/resume support, - the SUSPEND and RESUME - commands must be handled, too. - These commands are issued when the power-management status is - changed. Obviously, the SUSPEND and - RESUME commands - suspend and resume the pcm substream, and usually, they - are identical to the STOP and - START commands, respectively. - See the - Power Management section for details. - - - - As mentioned, this callback is atomic. You cannot call - functions which may sleep. - The trigger callback should be as minimal as possible, - just really triggering the DMA. The other stuff should be - initialized hw_params and prepare callbacks properly - beforehand. - -
- -
- pointer callback - - - - - - - - This callback is called when the PCM middle layer inquires - the current hardware position on the buffer. The position must - be returned in frames, - ranging from 0 to buffer_size - 1. - - - - This is called usually from the buffer-update routine in the - pcm middle layer, which is invoked when - snd_pcm_period_elapsed() is called in the - interrupt routine. Then the pcm middle layer updates the - position and calculates the available space, and wakes up the - sleeping poll threads, etc. - - - - This callback is also atomic. - -
- -
- copy and silence callbacks - - These callbacks are not mandatory, and can be omitted in - most cases. These callbacks are used when the hardware buffer - cannot be in the normal memory space. Some chips have their - own buffer on the hardware which is not mappable. In such a - case, you have to transfer the data manually from the memory - buffer to the hardware buffer. Or, if the buffer is - non-contiguous on both physical and virtual memory spaces, - these callbacks must be defined, too. - - - - If these two callbacks are defined, copy and set-silence - operations are done by them. The detailed will be described in - the later section Buffer and Memory - Management. - -
- -
- ack callback - - This callback is also not mandatory. This callback is called - when the appl_ptr is updated in read or write operations. - Some drivers like emu10k1-fx and cs46xx need to track the - current appl_ptr for the internal buffer, and this callback - is useful only for such a purpose. - - - This callback is atomic. - -
- -
- page callback - - - This callback is optional too. This callback is used - mainly for non-contiguous buffers. The mmap calls this - callback to get the page address. Some examples will be - explained in the later section Buffer and Memory - Management, too. - -
-
- -
- Interrupt Handler - - The rest of pcm stuff is the PCM interrupt handler. The - role of PCM interrupt handler in the sound driver is to update - the buffer position and to tell the PCM middle layer when the - buffer position goes across the prescribed period size. To - inform this, call the snd_pcm_period_elapsed() - function. - - - - There are several types of sound chips to generate the interrupts. - - -
- Interrupts at the period (fragment) boundary - - This is the most frequently found type: the hardware - generates an interrupt at each period boundary. - In this case, you can call - snd_pcm_period_elapsed() at each - interrupt. - - - - snd_pcm_period_elapsed() takes the - substream pointer as its argument. Thus, you need to keep the - substream pointer accessible from the chip instance. For - example, define substream field in the chip record to hold the - current running substream pointer, and set the pointer value - at open callback (and reset at close callback). - - - - If you acquire a spinlock in the interrupt handler, and the - lock is used in other pcm callbacks, too, then you have to - release the lock before calling - snd_pcm_period_elapsed(), because - snd_pcm_period_elapsed() calls other pcm - callbacks inside. - - - - Typical code would be like: - - - Interrupt Handler Case #1 - -lock); - .... - if (pcm_irq_invoked(chip)) { - /* call updater, unlock before it */ - spin_unlock(&chip->lock); - snd_pcm_period_elapsed(chip->substream); - spin_lock(&chip->lock); - /* acknowledge the interrupt if necessary */ - } - .... - spin_unlock(&chip->lock); - return IRQ_HANDLED; - } -]]> - - - -
- -
- High frequency timer interrupts - - This happense when the hardware doesn't generate interrupts - at the period boundary but issues timer interrupts at a fixed - timer rate (e.g. es1968 or ymfpci drivers). - In this case, you need to check the current hardware - position and accumulate the processed sample length at each - interrupt. When the accumulated size exceeds the period - size, call - snd_pcm_period_elapsed() and reset the - accumulator. - - - - Typical code would be like the following. - - - Interrupt Handler Case #2 - -lock); - .... - if (pcm_irq_invoked(chip)) { - unsigned int last_ptr, size; - /* get the current hardware pointer (in frames) */ - last_ptr = get_hw_ptr(chip); - /* calculate the processed frames since the - * last update - */ - if (last_ptr < chip->last_ptr) - size = runtime->buffer_size + last_ptr - - chip->last_ptr; - else - size = last_ptr - chip->last_ptr; - /* remember the last updated point */ - chip->last_ptr = last_ptr; - /* accumulate the size */ - chip->size += size; - /* over the period boundary? */ - if (chip->size >= runtime->period_size) { - /* reset the accumulator */ - chip->size %= runtime->period_size; - /* call updater */ - spin_unlock(&chip->lock); - snd_pcm_period_elapsed(substream); - spin_lock(&chip->lock); - } - /* acknowledge the interrupt if necessary */ - } - .... - spin_unlock(&chip->lock); - return IRQ_HANDLED; - } -]]> - - - -
- -
- On calling <function>snd_pcm_period_elapsed()</function> - - In both cases, even if more than one period are elapsed, you - don't have to call - snd_pcm_period_elapsed() many times. Call - only once. And the pcm layer will check the current hardware - pointer and update to the latest status. - -
-
- -
- Atomicity - - One of the most important (and thus difficult to debug) problems - in kernel programming are race conditions. - In the Linux kernel, they are usually avoided via spin-locks, mutexes - or semaphores. In general, if a race condition can happen - in an interrupt handler, it has to be managed atomically, and you - have to use a spinlock to protect the critical session. If the - critical section is not in interrupt handler code and - if taking a relatively long time to execute is acceptable, you - should use mutexes or semaphores instead. - - - - As already seen, some pcm callbacks are atomic and some are - not. For example, the hw_params callback is - non-atomic, while trigger callback is - atomic. This means, the latter is called already in a spinlock - held by the PCM middle layer. Please take this atomicity into - account when you choose a locking scheme in the callbacks. - - - - In the atomic callbacks, you cannot use functions which may call - schedule or go to - sleep. Semaphores and mutexes can sleep, - and hence they cannot be used inside the atomic callbacks - (e.g. trigger callback). - To implement some delay in such a callback, please use - udelay() or mdelay(). - - - - All three atomic callbacks (trigger, pointer, and ack) are - called with local interrupts disabled. - - -
-
- Constraints - - If your chip supports unconventional sample rates, or only the - limited samples, you need to set a constraint for the - condition. - - - - For example, in order to restrict the sample rates in the some - supported values, use - snd_pcm_hw_constraint_list(). - You need to call this function in the open callback. - - - Example of Hardware Constraints - -runtime, 0, - SNDRV_PCM_HW_PARAM_RATE, - &constraints_rates); - if (err < 0) - return err; - .... - } -]]> - - - - - - There are many different constraints. - Look at sound/pcm.h for a complete list. - You can even define your own constraint rules. - For example, let's suppose my_chip can manage a substream of 1 channel - if and only if the format is S16_LE, otherwise it supports any format - specified in the snd_pcm_hardware structure (or in any - other constraint_list). You can build a rule like this: - - - Example of Hardware Constraints for Channels - -min < 2) { - fmt.bits[0] &= SNDRV_PCM_FMTBIT_S16_LE; - return snd_mask_refine(f, &fmt); - } - return 0; - } -]]> - - - - - - Then you need to call this function to add your rule: - - - -runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS, - hw_rule_channels_by_format, 0, SNDRV_PCM_HW_PARAM_FORMAT, - -1); -]]> - - - - - - The rule function is called when an application sets the number of - channels. But an application can set the format before the number of - channels. Thus you also need to define the inverse rule: - - - Example of Hardware Constraints for Channels - -bits[0] == SNDRV_PCM_FMTBIT_S16_LE) { - ch.min = ch.max = 1; - ch.integer = 1; - return snd_interval_refine(c, &ch); - } - return 0; - } -]]> - - - - - - ...and in the open callback: - - -runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT, - hw_rule_format_by_channels, 0, SNDRV_PCM_HW_PARAM_CHANNELS, - -1); -]]> - - - - - - I won't give more details here, rather I - would like to say, Luke, use the source. - -
- - - - - - - - - Control Interface - -
- General - - The control interface is used widely for many switches, - sliders, etc. which are accessed from user-space. Its most - important use is the mixer interface. In other words, since ALSA - 0.9.x, all the mixer stuff is implemented on the control kernel API. - - - - ALSA has a well-defined AC97 control module. If your chip - supports only the AC97 and nothing else, you can skip this - section. - - - - The control API is defined in - <sound/control.h>. - Include this file if you want to add your own controls. - -
- -
- Definition of Controls - - To create a new control, you need to define the - following three - callbacks: info, - get and - put. Then, define a - struct snd_kcontrol_new record, such as: - - - Definition of a Control - - - - - - - - Most likely the control is created via - snd_ctl_new1(), and in such a case, you can - add the __devinitdata prefix to the - definition as above. - - - - The iface field specifies the control - type, SNDRV_CTL_ELEM_IFACE_XXX, which - is usually MIXER. - Use CARD for global controls that are not - logically part of the mixer. - If the control is closely associated with some specific device on - the sound card, use HWDEP, - PCM, RAWMIDI, - TIMER, or SEQUENCER, and - specify the device number with the - device and - subdevice fields. - - - - The name is the name identifier - string. Since ALSA 0.9.x, the control name is very important, - because its role is classified from its name. There are - pre-defined standard control names. The details are described in - the - Control Names subsection. - - - - The index field holds the index number - of this control. If there are several different controls with - the same name, they can be distinguished by the index - number. This is the case when - several codecs exist on the card. If the index is zero, you can - omit the definition above. - - - - The access field contains the access - type of this control. Give the combination of bit masks, - SNDRV_CTL_ELEM_ACCESS_XXX, there. - The details will be explained in - the - Access Flags subsection. - - - - The private_value field contains - an arbitrary long integer value for this record. When using - the generic info, - get and - put callbacks, you can pass a value - through this field. If several small numbers are necessary, you can - combine them in bitwise. Or, it's possible to give a pointer - (casted to unsigned long) of some record to this field, too. - - - - The tlv field can be used to provide - metadata about the control; see the - - Metadata subsection. - - - - The other three are - - callback functions. - -
- -
- Control Names - - There are some standards to define the control names. A - control is usually defined from the three parts as - SOURCE DIRECTION FUNCTION. - - - - The first, SOURCE, specifies the source - of the control, and is a string such as Master, - PCM, CD and - Line. There are many pre-defined sources. - - - - The second, DIRECTION, is one of the - following strings according to the direction of the control: - Playback, Capture, Bypass - Playback and Bypass Capture. Or, it can - be omitted, meaning both playback and capture directions. - - - - The third, FUNCTION, is one of the - following strings according to the function of the control: - Switch, Volume and - Route. - - - - The example of control names are, thus, Master Capture - Switch or PCM Playback Volume. - - - - There are some exceptions: - - -
- Global capture and playback - - Capture Source, Capture Switch - and Capture Volume are used for the global - capture (input) source, switch and volume. Similarly, - Playback Switch and Playback - Volume are used for the global output gain switch and - volume. - -
- -
- Tone-controls - - tone-control switch and volumes are specified like - Tone Control - XXX, e.g. Tone Control - - Switch, Tone Control - Bass, - Tone Control - Center. - -
- -
- 3D controls - - 3D-control switches and volumes are specified like 3D - Control - XXX, e.g. 3D Control - - Switch, 3D Control - Center, 3D - Control - Space. - -
- -
- Mic boost - - Mic-boost switch is set as Mic Boost or - Mic Boost (6dB). - - - - More precise information can be found in - Documentation/sound/alsa/ControlNames.txt. - -
-
- -
- Access Flags - - - The access flag is the bitmask which specifies the access type - of the given control. The default access type is - SNDRV_CTL_ELEM_ACCESS_READWRITE, - which means both read and write are allowed to this control. - When the access flag is omitted (i.e. = 0), it is - considered as READWRITE access as default. - - - - When the control is read-only, pass - SNDRV_CTL_ELEM_ACCESS_READ instead. - In this case, you don't have to define - the put callback. - Similarly, when the control is write-only (although it's a rare - case), you can use the WRITE flag instead, and - you don't need the get callback. - - - - If the control value changes frequently (e.g. the VU meter), - VOLATILE flag should be given. This means - that the control may be changed without - - notification. Applications should poll such - a control constantly. - - - - When the control is inactive, set - the INACTIVE flag, too. - There are LOCK and - OWNER flags to change the write - permissions. - - -
- -
- Callbacks - -
- info callback - - The info callback is used to get - detailed information on this control. This must store the - values of the given struct snd_ctl_elem_info - object. For example, for a boolean control with a single - element: - - - Example of info callback - -type = SNDRV_CTL_ELEM_TYPE_BOOLEAN; - uinfo->count = 1; - uinfo->value.integer.min = 0; - uinfo->value.integer.max = 1; - return 0; - } -]]> - - - - - - The type field specifies the type - of the control. There are BOOLEAN, - INTEGER, ENUMERATED, - BYTES, IEC958 and - INTEGER64. The - count field specifies the - number of elements in this control. For example, a stereo - volume would have count = 2. The - value field is a union, and - the values stored are depending on the type. The boolean and - integer types are identical. - - - - The enumerated type is a bit different from others. You'll - need to set the string for the currently given item index. - - - -type = SNDRV_CTL_ELEM_TYPE_ENUMERATED; - uinfo->count = 1; - uinfo->value.enumerated.items = 4; - if (uinfo->value.enumerated.item > 3) - uinfo->value.enumerated.item = 3; - strcpy(uinfo->value.enumerated.name, - texts[uinfo->value.enumerated.item]); - return 0; - } -]]> - - - - - - Some common info callbacks are available for your convenience: - snd_ctl_boolean_mono_info() and - snd_ctl_boolean_stereo_info(). - Obviously, the former is an info callback for a mono channel - boolean item, just like snd_myctl_mono_info - above, and the latter is for a stereo channel boolean item. - - -
- -
- get callback - - - This callback is used to read the current value of the - control and to return to user-space. - - - - For example, - - - Example of get callback - -value.integer.value[0] = get_some_value(chip); - return 0; - } -]]> - - - - - - The value field depends on - the type of control as well as on the info callback. For example, - the sb driver uses this field to store the register offset, - the bit-shift and the bit-mask. The - private_value field is set as follows: - - - - - - and is retrieved in callbacks like - - -private_value & 0xff; - int shift = (kcontrol->private_value >> 16) & 0xff; - int mask = (kcontrol->private_value >> 24) & 0xff; - .... - } -]]> - - - - - - In the get callback, - you have to fill all the elements if the - control has more than one elements, - i.e. count > 1. - In the example above, we filled only one element - (value.integer.value[0]) since it's - assumed as count = 1. - -
- -
- put callback - - - This callback is used to write a value from user-space. - - - - For example, - - - Example of put callback - -current_value != - ucontrol->value.integer.value[0]) { - change_current_value(chip, - ucontrol->value.integer.value[0]); - changed = 1; - } - return changed; - } -]]> - - - - As seen above, you have to return 1 if the value is - changed. If the value is not changed, return 0 instead. - If any fatal error happens, return a negative error code as - usual. - - - - As in the get callback, - when the control has more than one elements, - all elements must be evaluated in this callback, too. - -
- -
- Callbacks are not atomic - - All these three callbacks are basically not atomic. - -
-
- -
- Constructor - - When everything is ready, finally we can create a new - control. To create a control, there are two functions to be - called, snd_ctl_new1() and - snd_ctl_add(). - - - - In the simplest way, you can do like this: - - - - - - - - where my_control is the - struct snd_kcontrol_new object defined above, and chip - is the object pointer to be passed to - kcontrol->private_data - which can be referred to in callbacks. - - - - snd_ctl_new1() allocates a new - snd_kcontrol instance (that's why the definition - of my_control can be with - the __devinitdata - prefix), and snd_ctl_add assigns the given - control component to the card. - -
- -
- Change Notification - - If you need to change and update a control in the interrupt - routine, you can call snd_ctl_notify(). For - example, - - - - - - - - This function takes the card pointer, the event-mask, and the - control id pointer for the notification. The event-mask - specifies the types of notification, for example, in the above - example, the change of control values is notified. - The id pointer is the pointer of struct snd_ctl_elem_id - to be notified. - You can find some examples in es1938.c or - es1968.c for hardware volume interrupts. - -
- -
- Metadata - - To provide information about the dB values of a mixer control, use - on of the DECLARE_TLV_xxx macros from - <sound/tlv.h> to define a variable - containing this information, set thetlv.p - field to point to this variable, and include the - SNDRV_CTL_ELEM_ACCESS_TLV_READ flag in the - access field; like this: - - - - - - - - - The DECLARE_TLV_DB_SCALE macro defines - information about a mixer control where each step in the control's - value changes the dB value by a constant dB amount. - The first parameter is the name of the variable to be defined. - The second parameter is the minimum value, in units of 0.01 dB. - The third parameter is the step size, in units of 0.01 dB. - Set the fourth parameter to 1 if the minimum value actually mutes - the control. - - - - The DECLARE_TLV_DB_LINEAR macro defines - information about a mixer control where the control's value affects - the output linearly. - The first parameter is the name of the variable to be defined. - The second parameter is the minimum value, in units of 0.01 dB. - The third parameter is the maximum value, in units of 0.01 dB. - If the minimum value mutes the control, set the second parameter to - TLV_DB_GAIN_MUTE. - -
- - - - - - - - - API for AC97 Codec - -
- General - - The ALSA AC97 codec layer is a well-defined one, and you don't - have to write much code to control it. Only low-level control - routines are necessary. The AC97 codec API is defined in - <sound/ac97_codec.h>. - -
- -
- Full Code Example - - - Example of AC97 Interface - -private_data; - .... - /* read a register value here from the codec */ - return the_register_value; - } - - static void snd_mychip_ac97_write(struct snd_ac97 *ac97, - unsigned short reg, unsigned short val) - { - struct mychip *chip = ac97->private_data; - .... - /* write the given register value to the codec */ - } - - static int snd_mychip_ac97(struct mychip *chip) - { - struct snd_ac97_bus *bus; - struct snd_ac97_template ac97; - int err; - static struct snd_ac97_bus_ops ops = { - .write = snd_mychip_ac97_write, - .read = snd_mychip_ac97_read, - }; - - err = snd_ac97_bus(chip->card, 0, &ops, NULL, &bus); - if (err < 0) - return err; - memset(&ac97, 0, sizeof(ac97)); - ac97.private_data = chip; - return snd_ac97_mixer(bus, &ac97, &chip->ac97); - } - -]]> - - - -
- -
- Constructor - - To create an ac97 instance, first call snd_ac97_bus - with an ac97_bus_ops_t record with callback functions. - - - - - - - - The bus record is shared among all belonging ac97 instances. - - - - And then call snd_ac97_mixer() with an - struct snd_ac97_template - record together with the bus pointer created above. - - - -ac97); -]]> - - - - where chip->ac97 is a pointer to a newly created - ac97_t instance. - In this case, the chip pointer is set as the private data, so that - the read/write callback functions can refer to this chip instance. - This instance is not necessarily stored in the chip - record. If you need to change the register values from the - driver, or need the suspend/resume of ac97 codecs, keep this - pointer to pass to the corresponding functions. - -
- -
- Callbacks - - The standard callbacks are read and - write. Obviously they - correspond to the functions for read and write accesses to the - hardware low-level codes. - - - - The read callback returns the - register value specified in the argument. - - - -private_data; - .... - return the_register_value; - } -]]> - - - - Here, the chip can be cast from ac97->private_data. - - - - Meanwhile, the write callback is - used to set the register value. - - - - - - - - - - These callbacks are non-atomic like the control API callbacks. - - - - There are also other callbacks: - reset, - wait and - init. - - - - The reset callback is used to reset - the codec. If the chip requires a special kind of reset, you can - define this callback. - - - - The wait callback is used to - add some waiting time in the standard initialization of the codec. If the - chip requires the extra waiting time, define this callback. - - - - The init callback is used for - additional initialization of the codec. - -
- -
- Updating Registers in The Driver - - If you need to access to the codec from the driver, you can - call the following functions: - snd_ac97_write(), - snd_ac97_read(), - snd_ac97_update() and - snd_ac97_update_bits(). - - - - Both snd_ac97_write() and - snd_ac97_update() functions are used to - set a value to the given register - (AC97_XXX). The difference between them is - that snd_ac97_update() doesn't write a - value if the given value has been already set, while - snd_ac97_write() always rewrites the - value. - - - - - - - - - - snd_ac97_read() is used to read the value - of the given register. For example, - - - - - - - - - - snd_ac97_update_bits() is used to update - some bits in the given register. - - - - - - - - - - Also, there is a function to change the sample rate (of a - given register such as - AC97_PCM_FRONT_DAC_RATE) when VRA or - DRA is supported by the codec: - snd_ac97_set_rate(). - - - - - - - - - - The following registers are available to set the rate: - AC97_PCM_MIC_ADC_RATE, - AC97_PCM_FRONT_DAC_RATE, - AC97_PCM_LR_ADC_RATE, - AC97_SPDIF. When - AC97_SPDIF is specified, the register is - not really changed but the corresponding IEC958 status bits will - be updated. - -
- -
- Clock Adjustment - - In some chips, the clock of the codec isn't 48000 but using a - PCI clock (to save a quartz!). In this case, change the field - bus->clock to the corresponding - value. For example, intel8x0 - and es1968 drivers have their own function to read from the clock. - -
- -
- Proc Files - - The ALSA AC97 interface will create a proc file such as - /proc/asound/card0/codec97#0/ac97#0-0 and - ac97#0-0+regs. You can refer to these files to - see the current status and registers of the codec. - -
- -
- Multiple Codecs - - When there are several codecs on the same card, you need to - call snd_ac97_mixer() multiple times with - ac97.num=1 or greater. The num field - specifies the codec number. - - - - If you set up multiple codecs, you either need to write - different callbacks for each codec or check - ac97->num in the callback routines. - -
- - - - - - - - - MIDI (MPU401-UART) Interface - -
- General - - Many soundcards have built-in MIDI (MPU401-UART) - interfaces. When the soundcard supports the standard MPU401-UART - interface, most likely you can use the ALSA MPU401-UART API. The - MPU401-UART API is defined in - <sound/mpu401.h>. - - - - Some soundchips have a similar but slightly different - implementation of mpu401 stuff. For example, emu10k1 has its own - mpu401 routines. - -
- -
- Constructor - - To create a rawmidi object, call - snd_mpu401_uart_new(). - - - - - - - - - - The first argument is the card pointer, and the second is the - index of this component. You can create up to 8 rawmidi - devices. - - - - The third argument is the type of the hardware, - MPU401_HW_XXX. If it's not a special one, - you can use MPU401_HW_MPU401. - - - - The 4th argument is the I/O port address. Many - backward-compatible MPU401 have an I/O port such as 0x330. Or, it - might be a part of its own PCI I/O region. It depends on the - chip design. - - - - The 5th argument is a bitflag for additional information. - When the I/O port address above is part of the PCI I/O - region, the MPU401 I/O port might have been already allocated - (reserved) by the driver itself. In such a case, pass a bit flag - MPU401_INFO_INTEGRATED, - and the mpu401-uart layer will allocate the I/O ports by itself. - - - - When the controller supports only the input or output MIDI stream, - pass the MPU401_INFO_INPUT or - MPU401_INFO_OUTPUT bitflag, respectively. - Then the rawmidi instance is created as a single stream. - - - - MPU401_INFO_MMIO bitflag is used to change - the access method to MMIO (via readb and writeb) instead of - iob and outb. In this case, you have to pass the iomapped address - to snd_mpu401_uart_new(). - - - - When MPU401_INFO_TX_IRQ is set, the output - stream isn't checked in the default interrupt handler. The driver - needs to call snd_mpu401_uart_interrupt_tx() - by itself to start processing the output stream in the irq handler. - - - - Usually, the port address corresponds to the command port and - port + 1 corresponds to the data port. If not, you may change - the cport field of - struct snd_mpu401 manually - afterward. However, snd_mpu401 pointer is not - returned explicitly by - snd_mpu401_uart_new(). You need to cast - rmidi->private_data to - snd_mpu401 explicitly, - - - -private_data; -]]> - - - - and reset the cport as you like: - - - -cport = my_own_control_port; -]]> - - - - - - The 6th argument specifies the irq number for UART. If the irq - is already allocated, pass 0 to the 7th argument - (irq_flags). Otherwise, pass the flags - for irq allocation - (SA_XXX bits) to it, and the irq will be - reserved by the mpu401-uart layer. If the card doesn't generate - UART interrupts, pass -1 as the irq number. Then a timer - interrupt will be invoked for polling. - -
- -
- Interrupt Handler - - When the interrupt is allocated in - snd_mpu401_uart_new(), the private - interrupt handler is used, hence you don't have anything else to do - than creating the mpu401 stuff. Otherwise, you have to call - snd_mpu401_uart_interrupt() explicitly when - a UART interrupt is invoked and checked in your own interrupt - handler. - - - - In this case, you need to pass the private_data of the - returned rawmidi object from - snd_mpu401_uart_new() as the second - argument of snd_mpu401_uart_interrupt(). - - - -private_data, regs); -]]> - - - -
- - - - - - - - - RawMIDI Interface - -
- Overview - - - The raw MIDI interface is used for hardware MIDI ports that can - be accessed as a byte stream. It is not used for synthesizer - chips that do not directly understand MIDI. - - - - ALSA handles file and buffer management. All you have to do is - to write some code to move data between the buffer and the - hardware. - - - - The rawmidi API is defined in - <sound/rawmidi.h>. - -
- -
- Constructor - - - To create a rawmidi device, call the - snd_rawmidi_new function: - - -card, "MyMIDI", 0, outs, ins, &rmidi); - if (err < 0) - return err; - rmidi->private_data = chip; - strcpy(rmidi->name, "My MIDI"); - rmidi->info_flags = SNDRV_RAWMIDI_INFO_OUTPUT | - SNDRV_RAWMIDI_INFO_INPUT | - SNDRV_RAWMIDI_INFO_DUPLEX; -]]> - - - - - - The first argument is the card pointer, the second argument is - the ID string. - - - - The third argument is the index of this component. You can - create up to 8 rawmidi devices. - - - - The fourth and fifth arguments are the number of output and - input substreams, respectively, of this device (a substream is - the equivalent of a MIDI port). - - - - Set the info_flags field to specify - the capabilities of the device. - Set SNDRV_RAWMIDI_INFO_OUTPUT if there is - at least one output port, - SNDRV_RAWMIDI_INFO_INPUT if there is at - least one input port, - and SNDRV_RAWMIDI_INFO_DUPLEX if the device - can handle output and input at the same time. - - - - After the rawmidi device is created, you need to set the - operators (callbacks) for each substream. There are helper - functions to set the operators for all the substreams of a device: - - - - - - - - - The operators are usually defined like this: - - - - - - These callbacks are explained in the Callbacks - section. - - - - If there are more than one substream, you should give a - unique name to each of them: - - -streams[SNDRV_RAWMIDI_STREAM_OUTPUT].substreams, - list { - sprintf(substream->name, "My MIDI Port %d", substream->number + 1); - } - /* same for SNDRV_RAWMIDI_STREAM_INPUT */ -]]> - - - -
- -
- Callbacks - - - In all the callbacks, the private data that you've set for the - rawmidi device can be accessed as - substream->rmidi->private_data. - - - - - If there is more than one port, your callbacks can determine the - port index from the struct snd_rawmidi_substream data passed to each - callback: - - -number; -]]> - - - - -
- <function>open</function> callback - - - - - - - - - This is called when a substream is opened. - You can initialize the hardware here, but you shouldn't - start transmitting/receiving data yet. - -
- -
- <function>close</function> callback - - - - - - - - - Guess what. - - - - The open and close - callbacks of a rawmidi device are serialized with a mutex, - and can sleep. - -
- -
- <function>trigger</function> callback for output - substreams - - - - - - - - - This is called with a nonzero up - parameter when there is some data in the substream buffer that - must be transmitted. - - - - To read data from the buffer, call - snd_rawmidi_transmit_peek. It will - return the number of bytes that have been read; this will be - less than the number of bytes requested when there are no more - data in the buffer. - After the data have been transmitted successfully, call - snd_rawmidi_transmit_ack to remove the - data from the substream buffer: - - - - - - - - - If you know beforehand that the hardware will accept data, you - can use the snd_rawmidi_transmit function - which reads some data and removes them from the buffer at once: - - - - - - - - - If you know beforehand how many bytes you can accept, you can - use a buffer size greater than one with the - snd_rawmidi_transmit* functions. - - - - The trigger callback must not sleep. If - the hardware FIFO is full before the substream buffer has been - emptied, you have to continue transmitting data later, either - in an interrupt handler, or with a timer if the hardware - doesn't have a MIDI transmit interrupt. - - - - The trigger callback is called with a - zero up parameter when the transmission - of data should be aborted. - -
- -
- <function>trigger</function> callback for input - substreams - - - - - - - - - This is called with a nonzero up - parameter to enable receiving data, or with a zero - up parameter do disable receiving data. - - - - The trigger callback must not sleep; the - actual reading of data from the device is usually done in an - interrupt handler. - - - - When data reception is enabled, your interrupt handler should - call snd_rawmidi_receive for all received - data: - - - - - - -
- -
- <function>drain</function> callback - - - - - - - - - This is only used with output substreams. This function should wait - until all data read from the substream buffer have been transmitted. - This ensures that the device can be closed and the driver unloaded - without losing data. - - - - This callback is optional. If you do not set - drain in the struct snd_rawmidi_ops - structure, ALSA will simply wait for 50 milliseconds - instead. - -
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- - - - - - - - - Miscellaneous Devices - -
- FM OPL3 - - The FM OPL3 is still used in many chips (mainly for backward - compatibility). ALSA has a nice OPL3 FM control layer, too. The - OPL3 API is defined in - <sound/opl3.h>. - - - - FM registers can be directly accessed through the direct-FM API, - defined in <sound/asound_fm.h>. In - ALSA native mode, FM registers are accessed through - the Hardware-Dependant Device direct-FM extension API, whereas in - OSS compatible mode, FM registers can be accessed with the OSS - direct-FM compatible API in /dev/dmfmX device. - - - - To create the OPL3 component, you have two functions to - call. The first one is a constructor for the opl3_t - instance. - - - - - - - - - - The first argument is the card pointer, the second one is the - left port address, and the third is the right port address. In - most cases, the right port is placed at the left port + 2. - - - - The fourth argument is the hardware type. - - - - When the left and right ports have been already allocated by - the card driver, pass non-zero to the fifth argument - (integrated). Otherwise, the opl3 module will - allocate the specified ports by itself. - - - - When the accessing the hardware requires special method - instead of the standard I/O access, you can create opl3 instance - separately with snd_opl3_new(). - - - - - - - - - - Then set command, - private_data and - private_free for the private - access function, the private data and the destructor. - The l_port and r_port are not necessarily set. Only the - command must be set properly. You can retrieve the data - from the opl3->private_data field. - - - - After creating the opl3 instance via snd_opl3_new(), - call snd_opl3_init() to initialize the chip to the - proper state. Note that snd_opl3_create() always - calls it internally. - - - - If the opl3 instance is created successfully, then create a - hwdep device for this opl3. - - - - - - - - - - The first argument is the opl3_t instance you - created, and the second is the index number, usually 0. - - - - The third argument is the index-offset for the sequencer - client assigned to the OPL3 port. When there is an MPU401-UART, - give 1 for here (UART always takes 0). - -
- -
- Hardware-Dependent Devices - - Some chips need user-space access for special - controls or for loading the micro code. In such a case, you can - create a hwdep (hardware-dependent) device. The hwdep API is - defined in <sound/hwdep.h>. You can - find examples in opl3 driver or - isa/sb/sb16_csp.c. - - - - The creation of the hwdep instance is done via - snd_hwdep_new(). - - - - - - - - where the third argument is the index number. - - - - You can then pass any pointer value to the - private_data. - If you assign a private data, you should define the - destructor, too. The destructor function is set in - the private_free field. - - - -private_data = p; - hw->private_free = mydata_free; -]]> - - - - and the implementation of the destructor would be: - - - -private_data; - kfree(p); - } -]]> - - - - - - The arbitrary file operations can be defined for this - instance. The file operators are defined in - the ops table. For example, assume that - this chip needs an ioctl. - - - -ops.open = mydata_open; - hw->ops.ioctl = mydata_ioctl; - hw->ops.release = mydata_release; -]]> - - - - And implement the callback functions as you like. - -
- -
- IEC958 (S/PDIF) - - Usually the controls for IEC958 devices are implemented via - the control interface. There is a macro to compose a name string for - IEC958 controls, SNDRV_CTL_NAME_IEC958() - defined in <include/asound.h>. - - - - There are some standard controls for IEC958 status bits. These - controls use the type SNDRV_CTL_ELEM_TYPE_IEC958, - and the size of element is fixed as 4 bytes array - (value.iec958.status[x]). For the info - callback, you don't specify - the value field for this type (the count field must be set, - though). - - - - IEC958 Playback Con Mask is used to return the - bit-mask for the IEC958 status bits of consumer mode. Similarly, - IEC958 Playback Pro Mask returns the bitmask for - professional mode. They are read-only controls, and are defined - as MIXER controls (iface = - SNDRV_CTL_ELEM_IFACE_MIXER). - - - - Meanwhile, IEC958 Playback Default control is - defined for getting and setting the current default IEC958 - bits. Note that this one is usually defined as a PCM control - (iface = SNDRV_CTL_ELEM_IFACE_PCM), - although in some places it's defined as a MIXER control. - - - - In addition, you can define the control switches to - enable/disable or to set the raw bit mode. The implementation - will depend on the chip, but the control should be named as - IEC958 xxx, preferably using - the SNDRV_CTL_NAME_IEC958() macro. - - - - You can find several cases, for example, - pci/emu10k1, - pci/ice1712, or - pci/cmipci.c. - -
- - - - - - - - - Buffer and Memory Management - -
- Buffer Types - - ALSA provides several different buffer allocation functions - depending on the bus and the architecture. All these have a - consistent API. The allocation of physically-contiguous pages is - done via - snd_malloc_xxx_pages() function, where xxx - is the bus type. - - - - The allocation of pages with fallback is - snd_malloc_xxx_pages_fallback(). This - function tries to allocate the specified pages but if the pages - are not available, it tries to reduce the page sizes until - enough space is found. - - - - The release the pages, call - snd_free_xxx_pages() function. - - - - Usually, ALSA drivers try to allocate and reserve - a large contiguous physical space - at the time the module is loaded for the later use. - This is called pre-allocation. - As already written, you can call the following function at - pcm instance construction time (in the case of PCI bus). - - - - - - - - where size is the byte size to be - pre-allocated and the max is the maximum - size to be changed via the prealloc proc file. - The allocator will try to get an area as large as possible - within the given size. - - - - The second argument (type) and the third argument (device pointer) - are dependent on the bus. - In the case of the ISA bus, pass snd_dma_isa_data() - as the third argument with SNDRV_DMA_TYPE_DEV type. - For the continuous buffer unrelated to the bus can be pre-allocated - with SNDRV_DMA_TYPE_CONTINUOUS type and the - snd_dma_continuous_data(GFP_KERNEL) device pointer, - where GFP_KERNEL is the kernel allocation flag to - use. - For the PCI scatter-gather buffers, use - SNDRV_DMA_TYPE_DEV_SG with - snd_dma_pci_data(pci) - (see the - Non-Contiguous Buffers - section). - - - - Once the buffer is pre-allocated, you can use the - allocator in the hw_params callback: - - - - - - - - Note that you have to pre-allocate to use this function. - -
- -
- External Hardware Buffers - - Some chips have their own hardware buffers and the DMA - transfer from the host memory is not available. In such a case, - you need to either 1) copy/set the audio data directly to the - external hardware buffer, or 2) make an intermediate buffer and - copy/set the data from it to the external hardware buffer in - interrupts (or in tasklets, preferably). - - - - The first case works fine if the external hardware buffer is large - enough. This method doesn't need any extra buffers and thus is - more effective. You need to define the - copy and - silence callbacks for - the data transfer. However, there is a drawback: it cannot - be mmapped. The examples are GUS's GF1 PCM or emu8000's - wavetable PCM. - - - - The second case allows for mmap on the buffer, although you have - to handle an interrupt or a tasklet to transfer the data - from the intermediate buffer to the hardware buffer. You can find an - example in the vxpocket driver. - - - - Another case is when the chip uses a PCI memory-map - region for the buffer instead of the host memory. In this case, - mmap is available only on certain architectures like the Intel one. - In non-mmap mode, the data cannot be transferred as in the normal - way. Thus you need to define the copy and - silence callbacks as well, - as in the cases above. The examples are found in - rme32.c and rme96.c. - - - - The implementation of the copy and - silence callbacks depends upon - whether the hardware supports interleaved or non-interleaved - samples. The copy callback is - defined like below, a bit - differently depending whether the direction is playback or - capture: - - - - - - - - - - In the case of interleaved samples, the second argument - (channel) is not used. The third argument - (pos) points the - current position offset in frames. - - - - The meaning of the fourth argument is different between - playback and capture. For playback, it holds the source data - pointer, and for capture, it's the destination data pointer. - - - - The last argument is the number of frames to be copied. - - - - What you have to do in this callback is again different - between playback and capture directions. In the - playback case, you copy the given amount of data - (count) at the specified pointer - (src) to the specified offset - (pos) on the hardware buffer. When - coded like memcpy-like way, the copy would be like: - - - - - - - - - - For the capture direction, you copy the given amount of - data (count) at the specified offset - (pos) on the hardware buffer to the - specified pointer (dst). - - - - - - - - Note that both the position and the amount of data are given - in frames. - - - - In the case of non-interleaved samples, the implementation - will be a bit more complicated. - - - - You need to check the channel argument, and if it's -1, copy - the whole channels. Otherwise, you have to copy only the - specified channel. Please check - isa/gus/gus_pcm.c as an example. - - - - The silence callback is also - implemented in a similar way. - - - - - - - - - - The meanings of arguments are the same as in the - copy - callback, although there is no src/dst - argument. In the case of interleaved samples, the channel - argument has no meaning, as well as on - copy callback. - - - - The role of silence callback is to - set the given amount - (count) of silence data at the - specified offset (pos) on the hardware - buffer. Suppose that the data format is signed (that is, the - silent-data is 0), and the implementation using a memset-like - function would be like: - - - - - - - - - - In the case of non-interleaved samples, again, the - implementation becomes a bit more complicated. See, for example, - isa/gus/gus_pcm.c. - -
- -
- Non-Contiguous Buffers - - If your hardware supports the page table as in emu10k1 or the - buffer descriptors as in via82xx, you can use the scatter-gather - (SG) DMA. ALSA provides an interface for handling SG-buffers. - The API is provided in <sound/pcm.h>. - - - - For creating the SG-buffer handler, call - snd_pcm_lib_preallocate_pages() or - snd_pcm_lib_preallocate_pages_for_all() - with SNDRV_DMA_TYPE_DEV_SG - in the PCM constructor like other PCI pre-allocator. - You need to pass snd_dma_pci_data(pci), - where pci is the struct pci_dev pointer - of the chip as well. - The struct snd_sg_buf instance is created as - substream->dma_private. You can cast - the pointer like: - - - -dma_private; -]]> - - - - - - Then call snd_pcm_lib_malloc_pages() - in the hw_params callback - as well as in the case of normal PCI buffer. - The SG-buffer handler will allocate the non-contiguous kernel - pages of the given size and map them onto the virtually contiguous - memory. The virtual pointer is addressed in runtime->dma_area. - The physical address (runtime->dma_addr) is set to zero, - because the buffer is physically non-contigous. - The physical address table is set up in sgbuf->table. - You can get the physical address at a certain offset via - snd_pcm_sgbuf_get_addr(). - - - - When a SG-handler is used, you need to set - snd_pcm_sgbuf_ops_page as - the page callback. - (See - page callback section.) - - - - To release the data, call - snd_pcm_lib_free_pages() in the - hw_free callback as usual. - -
- -
- Vmalloc'ed Buffers - - It's possible to use a buffer allocated via - vmalloc, for example, for an intermediate - buffer. Since the allocated pages are not contiguous, you need - to set the page callback to obtain - the physical address at every offset. - - - - The implementation of page callback - would be like this: - - - - - - /* get the physical page pointer on the given offset */ - static struct page *mychip_page(struct snd_pcm_substream *substream, - unsigned long offset) - { - void *pageptr = substream->runtime->dma_area + offset; - return vmalloc_to_page(pageptr); - } -]]> - - - -
- - - - - - - - - Proc Interface - - ALSA provides an easy interface for procfs. The proc files are - very useful for debugging. I recommend you set up proc files if - you write a driver and want to get a running status or register - dumps. The API is found in - <sound/info.h>. - - - - To create a proc file, call - snd_card_proc_new(). - - - - - - - - where the second argument specifies the name of the proc file to be - created. The above example will create a file - my-file under the card directory, - e.g. /proc/asound/card0/my-file. - - - - Like other components, the proc entry created via - snd_card_proc_new() will be registered and - released automatically in the card registration and release - functions. - - - - When the creation is successful, the function stores a new - instance in the pointer given in the third argument. - It is initialized as a text proc file for read only. To use - this proc file as a read-only text file as it is, set the read - callback with a private data via - snd_info_set_text_ops(). - - - - - - - - where the second argument (chip) is the - private data to be used in the callbacks. The third parameter - specifies the read buffer size and the fourth - (my_proc_read) is the callback function, which - is defined like - - - - - - - - - - - In the read callback, use snd_iprintf() for - output strings, which works just like normal - printf(). For example, - - - -private_data; - - snd_iprintf(buffer, "This is my chip!\n"); - snd_iprintf(buffer, "Port = %ld\n", chip->port); - } -]]> - - - - - - The file permissions can be changed afterwards. As default, it's - set as read only for all users. If you want to add write - permission for the user (root as default), do as follows: - - - -mode = S_IFREG | S_IRUGO | S_IWUSR; -]]> - - - - and set the write buffer size and the callback - - - -c.text.write = my_proc_write; -]]> - - - - - - For the write callback, you can use - snd_info_get_line() to get a text line, and - snd_info_get_str() to retrieve a string from - the line. Some examples are found in - core/oss/mixer_oss.c, core/oss/and - pcm_oss.c. - - - - For a raw-data proc-file, set the attributes as follows: - - - -content = SNDRV_INFO_CONTENT_DATA; - entry->private_data = chip; - entry->c.ops = &my_file_io_ops; - entry->size = 4096; - entry->mode = S_IFREG | S_IRUGO; -]]> - - - - - - The callback is much more complicated than the text-file - version. You need to use a low-level I/O functions such as - copy_from/to_user() to transfer the - data. - - - - local_max_size) - size = local_max_size - pos; - if (copy_to_user(buf, local_data + pos, size)) - return -EFAULT; - return size; - } -]]> - - - - - - - - - - - - Power Management - - If the chip is supposed to work with suspend/resume - functions, you need to add power-management code to the - driver. The additional code for power-management should be - ifdef'ed with - CONFIG_PM. - - - - If the driver fully supports suspend/resume - that is, the device can be - properly resumed to its state when suspend was called, - you can set the SNDRV_PCM_INFO_RESUME flag - in the pcm info field. Usually, this is possible when the - registers of the chip can be safely saved and restored to - RAM. If this is set, the trigger callback is called with - SNDRV_PCM_TRIGGER_RESUME after the resume - callback completes. - - - - Even if the driver doesn't support PM fully but - partial suspend/resume is still possible, it's still worthy to - implement suspend/resume callbacks. In such a case, applications - would reset the status by calling - snd_pcm_prepare() and restart the stream - appropriately. Hence, you can define suspend/resume callbacks - below but don't set SNDRV_PCM_INFO_RESUME - info flag to the PCM. - - - - Note that the trigger with SUSPEND can always be called when - snd_pcm_suspend_all is called, - regardless of the SNDRV_PCM_INFO_RESUME flag. - The RESUME flag affects only the behavior - of snd_pcm_resume(). - (Thus, in theory, - SNDRV_PCM_TRIGGER_RESUME isn't needed - to be handled in the trigger callback when no - SNDRV_PCM_INFO_RESUME flag is set. But, - it's better to keep it for compatibility reasons.) - - - In the earlier version of ALSA drivers, a common - power-management layer was provided, but it has been removed. - The driver needs to define the suspend/resume hooks according to - the bus the device is connected to. In the case of PCI drivers, the - callbacks look like below: - - - - - - - - - - The scheme of the real suspend job is as follows. - - - Retrieve the card and the chip data. - Call snd_power_change_state() with - SNDRV_CTL_POWER_D3hot to change the - power status. - Call snd_pcm_suspend_all() to suspend the running PCM streams. - If AC97 codecs are used, call - snd_ac97_suspend() for each codec. - Save the register values if necessary. - Stop the hardware if necessary. - Disable the PCI device by calling - pci_disable_device(). Then, call - pci_save_state() at last. - - - - - A typical code would be like: - - - -private_data; - /* (2) */ - snd_power_change_state(card, SNDRV_CTL_POWER_D3hot); - /* (3) */ - snd_pcm_suspend_all(chip->pcm); - /* (4) */ - snd_ac97_suspend(chip->ac97); - /* (5) */ - snd_mychip_save_registers(chip); - /* (6) */ - snd_mychip_stop_hardware(chip); - /* (7) */ - pci_disable_device(pci); - pci_save_state(pci); - return 0; - } -]]> - - - - - - The scheme of the real resume job is as follows. - - - Retrieve the card and the chip data. - Set up PCI. First, call pci_restore_state(). - Then enable the pci device again by calling pci_enable_device(). - Call pci_set_master() if necessary, too. - Re-initialize the chip. - Restore the saved registers if necessary. - Resume the mixer, e.g. calling - snd_ac97_resume(). - Restart the hardware (if any). - Call snd_power_change_state() with - SNDRV_CTL_POWER_D0 to notify the processes. - - - - - A typical code would be like: - - - -private_data; - /* (2) */ - pci_restore_state(pci); - pci_enable_device(pci); - pci_set_master(pci); - /* (3) */ - snd_mychip_reinit_chip(chip); - /* (4) */ - snd_mychip_restore_registers(chip); - /* (5) */ - snd_ac97_resume(chip->ac97); - /* (6) */ - snd_mychip_restart_chip(chip); - /* (7) */ - snd_power_change_state(card, SNDRV_CTL_POWER_D0); - return 0; - } -]]> - - - - - - As shown in the above, it's better to save registers after - suspending the PCM operations via - snd_pcm_suspend_all() or - snd_pcm_suspend(). It means that the PCM - streams are already stoppped when the register snapshot is - taken. But, remember that you don't have to restart the PCM - stream in the resume callback. It'll be restarted via - trigger call with SNDRV_PCM_TRIGGER_RESUME - when necessary. - - - - OK, we have all callbacks now. Let's set them up. In the - initialization of the card, make sure that you can get the chip - data from the card instance, typically via - private_data field, in case you - created the chip data individually. - - - -private_data = chip; - .... - } -]]> - - - - When you created the chip data with - snd_card_create(), it's anyway accessible - via private_data field. - - - -private_data; - .... - } -]]> - - - - - - - If you need a space to save the registers, allocate the - buffer for it here, too, since it would be fatal - if you cannot allocate a memory in the suspend phase. - The allocated buffer should be released in the corresponding - destructor. - - - - And next, set suspend/resume callbacks to the pci_driver. - - - - - - - - - - - - - - - - Module Parameters - - There are standard module options for ALSA. At least, each - module should have the index, - id and enable - options. - - - - If the module supports multiple cards (usually up to - 8 = SNDRV_CARDS cards), they should be - arrays. The default initial values are defined already as - constants for easier programming: - - - - - - - - - - If the module supports only a single card, they could be single - variables, instead. enable option is not - always necessary in this case, but it would be better to have a - dummy option for compatibility. - - - - The module parameters must be declared with the standard - module_param()(), - module_param_array()() and - MODULE_PARM_DESC() macros. - - - - The typical coding would be like below: - - - - - - - - - - Also, don't forget to define the module description, classes, - license and devices. Especially, the recent modprobe requires to - define the module license as GPL, etc., otherwise the system is - shown as tainted. - - - - - - - - - - - - - - - - How To Put Your Driver Into ALSA Tree -
- General - - So far, you've learned how to write the driver codes. - And you might have a question now: how to put my own - driver into the ALSA driver tree? - Here (finally :) the standard procedure is described briefly. - - - - Suppose that you create a new PCI driver for the card - xyz. The card module name would be - snd-xyz. The new driver is usually put into the alsa-driver - tree, alsa-driver/pci directory in - the case of PCI cards. - Then the driver is evaluated, audited and tested - by developers and users. After a certain time, the driver - will go to the alsa-kernel tree (to the corresponding directory, - such as alsa-kernel/pci) and eventually - will be integrated into the Linux 2.6 tree (the directory would be - linux/sound/pci). - - - - In the following sections, the driver code is supposed - to be put into alsa-driver tree. The two cases are covered: - a driver consisting of a single source file and one consisting - of several source files. - -
- -
- Driver with A Single Source File - - - - - Modify alsa-driver/pci/Makefile - - - - Suppose you have a file xyz.c. Add the following - two lines - - - - - - - - - - - Create the Kconfig entry - - - - Add the new entry of Kconfig for your xyz driver. - - - - - - - the line, select SND_PCM, specifies that the driver xyz supports - PCM. In addition to SND_PCM, the following components are - supported for select command: - SND_RAWMIDI, SND_TIMER, SND_HWDEP, SND_MPU401_UART, - SND_OPL3_LIB, SND_OPL4_LIB, SND_VX_LIB, SND_AC97_CODEC. - Add the select command for each supported component. - - - - Note that some selections imply the lowlevel selections. - For example, PCM includes TIMER, MPU401_UART includes RAWMIDI, - AC97_CODEC includes PCM, and OPL3_LIB includes HWDEP. - You don't need to give the lowlevel selections again. - - - - For the details of Kconfig script, refer to the kbuild - documentation. - - - - - - - Run cvscompile script to re-generate the configure script and - build the whole stuff again. - - - - -
- -
- Drivers with Several Source Files - - Suppose that the driver snd-xyz have several source files. - They are located in the new subdirectory, - pci/xyz. - - - - - Add a new directory (xyz) in - alsa-driver/pci/Makefile as below - - - - - - - - - - - - Under the directory xyz, create a Makefile - - - Sample Makefile for a driver xyz - - - - - - - - - - Create the Kconfig entry - - - - This procedure is as same as in the last section. - - - - - - Run cvscompile script to re-generate the configure script and - build the whole stuff again. - - - - -
- - - - - - - - Useful Functions - -
- <function>snd_printk()</function> and friends - - ALSA provides a verbose version of the - printk() function. If a kernel config - CONFIG_SND_VERBOSE_PRINTK is set, this - function prints the given message together with the file name - and the line of the caller. The KERN_XXX - prefix is processed as - well as the original printk() does, so it's - recommended to add this prefix, e.g. - - - - - - - - - - There are also printk()'s for - debugging. snd_printd() can be used for - general debugging purposes. If - CONFIG_SND_DEBUG is set, this function is - compiled, and works just like - snd_printk(). If the ALSA is compiled - without the debugging flag, it's ignored. - - - - snd_printdd() is compiled in only when - CONFIG_SND_DEBUG_VERBOSE is set. Please note - that CONFIG_SND_DEBUG_VERBOSE is not set as default - even if you configure the alsa-driver with - option. You need to give - explicitly option instead. - -
- -
- <function>snd_BUG()</function> - - It shows the BUG? message and - stack trace as well as snd_BUG_ON at the point. - It's useful to show that a fatal error happens there. - - - When no debug flag is set, this macro is ignored. - -
- -
- <function>snd_BUG_ON()</function> - - snd_BUG_ON() macro is similar with - WARN_ON() macro. For example, - - - - - - - - or it can be used as the condition, - - - - - - - - - - The macro takes an conditional expression to evaluate. - When CONFIG_SND_DEBUG, is set, the - expression is actually evaluated. If it's non-zero, it shows - the warning message such as - BUG? (xxx) - normally followed by stack trace. It returns the evaluated - value. - When no CONFIG_SND_DEBUG is set, this - macro always returns zero. - - -
- - - - - - - - - Acknowledgments - - I would like to thank Phil Kerr for his help for improvement and - corrections of this document. - - - Kevin Conder reformatted the original plain-text to the - DocBook format. - - - Giuliano Pochini corrected typos and contributed the example codes - in the hardware constraints section. - - - -- cgit v1.2.3 From 0bcd783c1f0396b68410fdb41fbe196fbc1947af Mon Sep 17 00:00:00 2001 From: Timur Tabi Date: Wed, 4 Mar 2009 14:55:30 -0600 Subject: powerpc: add fsl,fifo-depth property to Freescale SSI device nodes The Freescale Serial Synchronous Interface (SSI) is an audio device present on some Freescale SOCs. Various implementations of the SSI have a different transmit and receive FIFO depth, but are otherwise identical. To support these variations, add a new property fsl,fifo-depth to the SSI node that specifies the depth of the FIFOs. Also update the MPC8610 HPCD device tree with this property. Signed-off-by: Timur Tabi Signed-off-by: Kumar Gala --- Documentation/powerpc/dts-bindings/fsl/ssi.txt | 2 ++ 1 file changed, 2 insertions(+) (limited to 'Documentation') diff --git a/Documentation/powerpc/dts-bindings/fsl/ssi.txt b/Documentation/powerpc/dts-bindings/fsl/ssi.txt index a2d963998a6..73133228893 100644 --- a/Documentation/powerpc/dts-bindings/fsl/ssi.txt +++ b/Documentation/powerpc/dts-bindings/fsl/ssi.txt @@ -30,6 +30,8 @@ Required properties: - fsl,capture-dma: phandle to a node for the DMA channel to use for capture (recording) of audio. This is typically dictated by SOC design. See the notes below. +- fsl,fifo-depth: the number of elements in the transmit and receive FIFOs. + This number is the maximum allowed value for SFCSR[TFWM0]. Optional properties: - codec-handle : phandle to a 'codec' node that defines an audio -- cgit v1.2.3 From 6dfc0d2c4b9a5455c60e0b9ee95bbf22fc516cef Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Tue, 10 Mar 2009 07:54:20 +0100 Subject: ALSA: hda - Add missing models to documentation Signed-off-by: Takashi Iwai --- Documentation/sound/alsa/HD-Audio-Models.txt | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/sound/alsa/HD-Audio-Models.txt b/Documentation/sound/alsa/HD-Audio-Models.txt index 80b796e4a80..f9253ea3c19 100644 --- a/Documentation/sound/alsa/HD-Audio-Models.txt +++ b/Documentation/sound/alsa/HD-Audio-Models.txt @@ -344,7 +344,9 @@ STAC92HD71B* dell-m4-1 Dell desktops dell-m4-2 Dell desktops dell-m4-3 Dell desktops - hp-m4 HP dv laptops + hp-m4 HP mini 1000 + hp-dv5 HP dv series + hp-hdx HP HDX series auto BIOS setup (default) STAC92HD73* @@ -361,6 +363,7 @@ STAC92HD83* =========== ref Reference board mic-ref Reference board with power managment for ports + dell-s14 Dell laptop auto BIOS setup (default) STAC9872 -- cgit v1.2.3 From 307282c8990c5658604b9fda8a64a9a07079b850 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Thu, 12 Mar 2009 18:17:58 +0100 Subject: ALSA: hda - Add model=vaio for STAC9872 Add the default pin config for model=vaio (in case of broken BIOS). Signed-off-by: Takashi Iwai --- Documentation/sound/alsa/HD-Audio-Models.txt | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/sound/alsa/HD-Audio-Models.txt b/Documentation/sound/alsa/HD-Audio-Models.txt index f9253ea3c19..8eec05bc079 100644 --- a/Documentation/sound/alsa/HD-Audio-Models.txt +++ b/Documentation/sound/alsa/HD-Audio-Models.txt @@ -368,4 +368,5 @@ STAC92HD83* STAC9872 ======== - N/A + vaio VAIO laptop without SPDIF + auto BIOS setup (default) -- cgit v1.2.3 From 71969fd9e2c523d22bf1742eb31f1562247710eb Mon Sep 17 00:00:00 2001 From: Boaz Harrosh Date: Sun, 25 Jan 2009 16:50:02 +0200 Subject: [SCSI] major.h: char-major number for OSD device driver Allocate major 260 for osd. Signed-off-by: Boaz Harrosh CC: Torben Mathiasen Signed-off-by: James Bottomley --- Documentation/devices.txt | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'Documentation') diff --git a/Documentation/devices.txt b/Documentation/devices.txt index 2be08240ee8..62254d4510c 100644 --- a/Documentation/devices.txt +++ b/Documentation/devices.txt @@ -3145,6 +3145,12 @@ Your cooperation is appreciated. 1 = /dev/blockrom1 Second ROM card's translation layer interface ... +260 char OSD (Object-based-device) SCSI Device + 0 = /dev/osd0 First OSD Device + 1 = /dev/osd1 Second OSD Device + ... + 255 = /dev/osd255 256th OSD Device + **** ADDITIONAL /dev DIRECTORY ENTRIES This section details additional entries that should or may exist in -- cgit v1.2.3 From 78e0c621deca08e5f802383dbe75fd20b258ea4e Mon Sep 17 00:00:00 2001 From: Boaz Harrosh Date: Sun, 25 Jan 2009 17:21:40 +0200 Subject: [SCSI] osd: Documentation for OSD library Add osd.txt to Documentation/scsi/ Signed-off-by: Boaz Harrosh Reviewed-by: Benny Halevy Signed-off-by: James Bottomley --- Documentation/scsi/osd.txt | 198 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 198 insertions(+) create mode 100644 Documentation/scsi/osd.txt (limited to 'Documentation') diff --git a/Documentation/scsi/osd.txt b/Documentation/scsi/osd.txt new file mode 100644 index 00000000000..da162f7fd5f --- /dev/null +++ b/Documentation/scsi/osd.txt @@ -0,0 +1,198 @@ +The OSD Standard +================ +OSD (Object-Based Storage Device) is a T10 SCSI command set that is designed +to provide efficient operation of input/output logical units that manage the +allocation, placement, and accessing of variable-size data-storage containers, +called objects. Objects are intended to contain operating system and application +constructs. Each object has associated attributes attached to it, which are +integral part of the object and provide metadata about the object. The standard +defines some common obligatory attributes, but user attributes can be added as +needed. + +See: http://www.t10.org/ftp/t10/drafts/osd2/ for the latest draft for OSD 2 +or search the web for "OSD SCSI" + +OSD in the Linux Kernel +======================= +osd-initiator: + The main component of OSD in Kernel is the osd-initiator library. Its main +user is intended to be the pNFS-over-objects layout driver, which uses objects +as its back-end data storage. Other clients are the other osd parts listed below. + +osd-uld: + This is a SCSI ULD that registers for OSD type devices and provides a testing +platform, both for the in-kernel initiator as well as connected targets. It +currently has no useful user-mode API, though it could have if need be. + +exofs: + Is an OSD based Linux file system. It uses the osd-initiator and osd-uld, +to export a usable file system for users. +See Documentation/filesystems/exofs.txt for more details + +osd target: + There are no current plans for an OSD target implementation in kernel. For all +needs, a user-mode target that is based on the scsi tgt target framework is +available from Ohio Supercomputer Center (OSC) at: +http://www.open-osd.org/bin/view/Main/OscOsdProject +There are several other target implementations. See http://open-osd.org for more +links. + +Files and Folders +================= +This is the complete list of files included in this work: +include/scsi/ + osd_initiator.h Main API for the initiator library + osd_types.h Common OSD types + osd_sec.h Security Manager API + osd_protocol.h Wire definitions of the OSD standard protocol + osd_attributes.h Wire definitions of OSD attributes + +drivers/scsi/osd/ + osd_initiator.c OSD-Initiator library implementation + osd_uld.c The OSD scsi ULD + osd_ktest.{h,c} In-kernel test suite (called by osd_uld) + osd_debug.h Some printk macros + Makefile For both in-tree and out-of-tree compilation + Kconfig Enables inclusion of the different pieces + osd_test.c User-mode application to call the kernel tests + +The OSD-Initiator Library +========================= +osd_initiator is a low level implementation of an osd initiator encoder. +But even though, it should be intuitive and easy to use. Perhaps over time an +higher lever will form that automates some of the more common recipes. + +init/fini: +- osd_dev_init() associates a scsi_device with an osd_dev structure + and initializes some global pools. This should be done once per scsi_device + (OSD LUN). The osd_dev structure is needed for calling osd_start_request(). + +- osd_dev_fini() cleans up before a osd_dev/scsi_device destruction. + +OSD commands encoding, execution, and decoding of results: + +struct osd_request's is used to iteratively encode an OSD command and carry +its state throughout execution. Each request goes through these stages: + +a. osd_start_request() allocates the request. + +b. Any of the osd_req_* methods is used to encode a request of the specified + type. + +c. osd_req_add_{get,set}_attr_* may be called to add get/set attributes to the + CDB. "List" or "Page" mode can be used exclusively. The attribute-list API + can be called multiple times on the same request. However, only one + attribute-page can be read, as mandated by the OSD standard. + +d. osd_finalize_request() computes offsets into the data-in and data-out buffers + and signs the request using the provided capability key and integrity- + check parameters. + +e. osd_execute_request() may be called to execute the request via the block + layer and wait for its completion. The request can be executed + asynchronously by calling the block layer API directly. + +f. After execution, osd_req_decode_sense() can be called to decode the request's + sense information. + +g. osd_req_decode_get_attr() may be called to retrieve osd_add_get_attr_list() + values. + +h. osd_end_request() must be called to deallocate the request and any resource + associated with it. Note that osd_end_request cleans up the request at any + stage and it must always be called after a successful osd_start_request(). + +osd_request's structure: + +The OSD standard defines a complex structure of IO segments pointed to by +members in the CDB. Up to 3 segments can be deployed in the IN-Buffer and up to +4 in the OUT-Buffer. The ASCII illustration below depicts a secure-read with +associated get+set of attributes-lists. Other combinations very on the same +basic theme. From no-segments-used up to all-segments-used. + +|________OSD-CDB__________| +| | +|read_len (offset=0) -|---------\ +| | | +|get_attrs_list_length | | +|get_attrs_list_offset -|----\ | +| | | | +|retrieved_attrs_alloc_len| | | +|retrieved_attrs_offset -|----|----|-\ +| | | | | +|set_attrs_list_length | | | | +|set_attrs_list_offset -|-\ | | | +| | | | | | +|in_data_integ_offset -|-|--|----|-|-\ +|out_data_integ_offset -|-|--|--\ | | | +\_________________________/ | | | | | | + | | | | | | +|_______OUT-BUFFER________| | | | | | | +| Set attr list | + +More up-to-date information can be found on: +http://open-osd.org + +Boaz Harrosh +Benny Halevy + +References +========== +Weber, R., "SCSI Object-Based Storage Device Commands", +T10/1355-D ANSI/INCITS 400-2004, +http://www.t10.org/ftp/t10/drafts/osd/osd-r10.pdf + +Weber, R., "SCSI Object-Based Storage Device Commands -2 (OSD-2)" +T10/1729-D, Working Draft, rev. 3 +http://www.t10.org/ftp/t10/drafts/osd2/osd2r03.pdf -- cgit v1.2.3 From a9d0a1a38352c4fb8946e73b3e42ba4ada29e733 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Tue, 3 Mar 2009 16:58:16 +0100 Subject: genirq: add doc to struct irqaction Impact: documentation struct irqaction is not documented. Add kernel doc comments and add interrupt.h to the genirq docbook. Signed-off-by: Thomas Gleixner --- Documentation/DocBook/genericirq.tmpl | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/DocBook/genericirq.tmpl b/Documentation/DocBook/genericirq.tmpl index 3a882d9a90a..c671a016809 100644 --- a/Documentation/DocBook/genericirq.tmpl +++ b/Documentation/DocBook/genericirq.tmpl @@ -440,6 +440,7 @@ desc->chip->end(); used in the generic IRQ layer. !Iinclude/linux/irq.h +!Iinclude/linux/interrupt.h -- cgit v1.2.3 From 0e57aa11abb15b70db53d1f95ae70b3c980ac885 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Fri, 13 Mar 2009 14:34:05 +0100 Subject: genirq: deprecate __do_IRQ Two years migration time is enough. Remove the compability cruft. Add the deprecated warning in kernel/irq/handle.c because marking __do_IRQ itself is way too noisy. Signed-off-by: Thomas Gleixner --- Documentation/feature-removal-schedule.txt | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'Documentation') diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 20d3b94703a..63b4550411b 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -344,3 +344,11 @@ Why: See commits 129f8ae9b1b5be94517da76009ea956e89104ce8 and Removal is subject to fixing any remaining bugs in ACPI which may cause the thermal throttling not to happen at the right time. Who: Dave Jones , Matthew Garrett + +----------------------------- + +What: __do_IRQ all in one fits nothing interrupt handler +When: 2.6.32 +Why: __do_IRQ was kept for easy migration to the type flow handlers. + More than two years of migration time is enough. +Who: Thomas Gleixner -- cgit v1.2.3 From cb065c06b6cc615a58860d619d7fa7952cd6a18b Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Fri, 13 Mar 2009 14:40:27 +0100 Subject: genirq: deprecate obsolete typedefs and defines More than two years is enough migration time. Remove the compability cruft. Signed-off-by: Thomas Gleixner --- Documentation/feature-removal-schedule.txt | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'Documentation') diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 63b4550411b..9aa1dda5d38 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -352,3 +352,12 @@ When: 2.6.32 Why: __do_IRQ was kept for easy migration to the type flow handlers. More than two years of migration time is enough. Who: Thomas Gleixner + +----------------------------- + +What: obsolete generic irq defines and typedefs +When: 2.6.30 +Why: The defines and typedefs (hw_interrupt_type, no_irq_type, irq_desc_t) + have been kept around for migration reasons. After more than two years + it's time to remove them finally +Who: Thomas Gleixner -- cgit v1.2.3 From 09e1c061484005aa26264c3f82f2c83a273c4094 Mon Sep 17 00:00:00 2001 From: PJ Waskiewicz Date: Fri, 13 Mar 2009 22:15:54 +0000 Subject: ixgbe: Add documentation for the driver Documentation for the ixgbe driver in the kernel docs area is missing. This adds that documentation. Signed-off-by: Peter P Waskiewicz Jr Signed-off-by: Jeff Kirsher Signed-off-by: David S. Miller --- Documentation/networking/ixgbe.txt | 199 +++++++++++++++++++++++++++++++++++++ 1 file changed, 199 insertions(+) create mode 100644 Documentation/networking/ixgbe.txt (limited to 'Documentation') diff --git a/Documentation/networking/ixgbe.txt b/Documentation/networking/ixgbe.txt new file mode 100644 index 00000000000..eeb68685c78 --- /dev/null +++ b/Documentation/networking/ixgbe.txt @@ -0,0 +1,199 @@ +Linux Base Driver for 10 Gigabit PCI Express Intel(R) Network Connection +======================================================================== + +March 10, 2009 + + +Contents +======== + +- In This Release +- Identifying Your Adapter +- Building and Installation +- Additional Configurations +- Support + + + +In This Release +=============== + +This file describes the ixgbe Linux Base Driver for the 10 Gigabit PCI +Express Intel(R) Network Connection. This driver includes support for +Itanium(R)2-based systems. + +For questions related to hardware requirements, refer to the documentation +supplied with your 10 Gigabit adapter. All hardware requirements listed apply +to use with Linux. + +The following features are available in this kernel: + - Native VLANs + - Channel Bonding (teaming) + - SNMP + - Generic Receive Offload + - Data Center Bridging + +Channel Bonding documentation can be found in the Linux kernel source: +/Documentation/networking/bonding.txt + +Ethtool, lspci, and ifconfig can be used to display device and driver +specific information. + + +Identifying Your Adapter +======================== + +This driver supports devices based on the 82598 controller and the 82599 +controller. + +For specific information on identifying which adapter you have, please visit: + + http://support.intel.com/support/network/sb/CS-008441.htm + + +Building and Installation +========================= + +select m for "Intel(R) 10GbE PCI Express adapters support" located at: + Location: + -> Device Drivers + -> Network device support (NETDEVICES [=y]) + -> Ethernet (10000 Mbit) (NETDEV_10000 [=y]) + +1. make modules & make modules_install + +2. Load the module: + +# modprobe ixgbe + + The insmod command can be used if the full + path to the driver module is specified. For example: + + insmod /lib/modules//kernel/drivers/net/ixgbe/ixgbe.ko + + With 2.6 based kernels also make sure that older ixgbe drivers are + removed from the kernel, before loading the new module: + + rmmod ixgbe; modprobe ixgbe + +3. Assign an IP address to the interface by entering the following, where + x is the interface number: + + ifconfig ethx + +4. Verify that the interface works. Enter the following, where + is the IP address for another machine on the same subnet as the interface + that is being tested: + + ping + + +Additional Configurations +========================= + + Viewing Link Messages + --------------------- + Link messages will not be displayed to the console if the distribution is + restricting system messages. In order to see network driver link messages on + your console, set dmesg to eight by entering the following: + + dmesg -n 8 + + NOTE: This setting is not saved across reboots. + + + Jumbo Frames + ------------ + The driver supports Jumbo Frames for all adapters. Jumbo Frames support is + enabled by changing the MTU to a value larger than the default of 1500. + The maximum value for the MTU is 16110. Use the ifconfig command to + increase the MTU size. For example: + + ifconfig ethx mtu 9000 up + + The maximum MTU setting for Jumbo Frames is 16110. This value coincides + with the maximum Jumbo Frames size of 16128. + + Generic Receive Offload, aka GRO + -------------------------------- + The driver supports the in-kernel software implementation of GRO. GRO has + shown that by coalescing Rx traffic into larger chunks of data, CPU + utilization can be significantly reduced when under large Rx load. GRO is an + evolution of the previously-used LRO interface. GRO is able to coalesce + other protocols besides TCP. It's also safe to use with configurations that + are problematic for LRO, namely bridging and iSCSI. + + GRO is enabled by default in the driver. Future versions of ethtool will + support disabling and re-enabling GRO on the fly. + + + Data Center Bridging, aka DCB + ----------------------------- + + DCB is a configuration Quality of Service implementation in hardware. + It uses the VLAN priority tag (802.1p) to filter traffic. That means + that there are 8 different priorities that traffic can be filtered into. + It also enables priority flow control which can limit or eliminate the + number of dropped packets during network stress. Bandwidth can be + allocated to each of these priorities, which is enforced at the hardware + level. + + To enable DCB support in ixgbe, you must enable the DCB netlink layer to + allow the userspace tools (see below) to communicate with the driver. + This can be found in the kernel configuration here: + + -> Networking support + -> Networking options + -> Data Center Bridging support + + Once this is selected, DCB support must be selected for ixgbe. This can + be found here: + + -> Device Drivers + -> Network device support (NETDEVICES [=y]) + -> Ethernet (10000 Mbit) (NETDEV_10000 [=y]) + -> Intel(R) 10GbE PCI Express adapters support + -> Data Center Bridging (DCB) Support + + After these options are selected, you must rebuild your kernel and your + modules. + + In order to use DCB, userspace tools must be downloaded and installed. + The dcbd tools can be found at: + + http://e1000.sf.net + + + Ethtool + ------- + The driver utilizes the ethtool interface for driver configuration and + diagnostics, as well as displaying statistical information. Ethtool + version 3.0 or later is required for this functionality. + + The latest release of ethtool can be found from + http://sourceforge.net/projects/gkernel. + + + NAPI + ---- + + NAPI (Rx polling mode) is supported in the ixgbe driver. NAPI is enabled + by default in the driver. + + See www.cyberus.ca/~hadi/usenix-paper.tgz for more information on NAPI. + + +Support +======= + +For general information, go to the Intel support website at: + + http://support.intel.com + +or the Intel Wired Networking project hosted by Sourceforge at: + + http://e1000.sourceforge.net + +If an issue is identified with the released source code on the supported +kernel with a supported adapter, email the specific information related +to the issue to e1000-devel@lists.sf.net -- cgit v1.2.3 From 5f0fbf9ecaf354fa4bbf266fffdea2ea3d14a0ed Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Tue, 16 Sep 2008 13:05:53 -0400 Subject: [ARM] fixmap support This is the minimum fixmap interface expected to be implemented by architectures supporting highmem. We have a second level page table already allocated and covering 0xfff00000-0xffffffff because the exception vector page is located at 0xffff0000, and various cache tricks already use some entries above 0xffff0000. Therefore the PTEs covering 0xfff00000-0xfffeffff are free to be used. However the XScale cache flushing code already uses virtual addresses between 0xfffe0000 and 0xfffeffff. So this reserves the 0xfff00000-0xfffdffff range for fixmap stuff. The Documentation/arm/memory.txt information is updated accordingly, including the information about the actual top of DMA memory mapping region which didn't match the code. Signed-off-by: Nicolas Pitre --- Documentation/arm/memory.txt | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/arm/memory.txt b/Documentation/arm/memory.txt index dc6045577a8..43cb1004d35 100644 --- a/Documentation/arm/memory.txt +++ b/Documentation/arm/memory.txt @@ -29,7 +29,14 @@ ffff0000 ffff0fff CPU vector page. CPU supports vector relocation (control register V bit.) -ffc00000 fffeffff DMA memory mapping region. Memory returned +fffe0000 fffeffff XScale cache flush area. This is used + in proc-xscale.S to flush the whole data + cache. Free for other usage on non-XScale. + +fff00000 fffdffff Fixmap mapping region. Addresses provided + by fix_to_virt() will be located here. + +ffc00000 ffefffff DMA memory mapping region. Memory returned by the dma_alloc_xxx functions will be dynamically mapped here. -- cgit v1.2.3 From 76398425bb06b07cc3a3b1ce169c67dc9d6874ed Mon Sep 17 00:00:00 2001 From: Jonathan Corbet Date: Sun, 1 Feb 2009 14:26:59 -0700 Subject: Move FASYNC bit handling to f_op->fasync() Removing the BKL from FASYNC handling ran into the challenge of keeping the setting of the FASYNC bit in filp->f_flags atomic with regard to calls to the underlying fasync() function. Andi Kleen suggested moving the handling of that bit into fasync(); this patch does exactly that. As a result, we have a couple of internal API changes: fasync() must now manage the FASYNC bit, and it will be called without the BKL held. As it happens, every fasync() implementation in the kernel with one exception calls fasync_helper(). So, if we make fasync_helper() set the FASYNC bit, we can avoid making any changes to the other fasync() functions - as long as those functions, themselves, have proper locking. Most fasync() implementations do nothing but call fasync_helper() - which has its own lock - so they are easily verified as correct. The BKL had already been pushed down into the rest. The networking code has its own version of fasync_helper(), so that code has been augmented with explicit FASYNC bit handling. Cc: Al Viro Cc: David Miller Reviewed-by: Christoph Hellwig Signed-off-by: Jonathan Corbet --- Documentation/filesystems/Locking | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'Documentation') diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index ec6a9392a17..4e78ce67784 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -437,8 +437,11 @@ grab BKL for cases when we close a file that had been opened r/w, but that can and should be done using the internal locking with smaller critical areas). Current worst offender is ext2_get_block()... -->fasync() is a mess. This area needs a big cleanup and that will probably -affect locking. +->fasync() is called without BKL protection, and is responsible for +maintaining the FASYNC bit in filp->f_flags. Most instances call +fasync_helper(), which does that maintenance, so it's not normally +something one needs to worry about. Return values > 0 will be mapped to +zero in the VFS layer. ->readdir() and ->ioctl() on directories must be changed. Ideally we would move ->readdir() to inode_operations and use a separate method for directory -- cgit v1.2.3 From 187f9c3f05373df4f7cbae2e656450acdbba7558 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Fri, 9 Jan 2009 16:28:07 +0100 Subject: dma-debug: Documentation update Impact: add documentation about DMA-API debugging to DMA-API.txt Signed-off-by: Joerg Roedel --- Documentation/DMA-API.txt | 106 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 106 insertions(+) (limited to 'Documentation') diff --git a/Documentation/DMA-API.txt b/Documentation/DMA-API.txt index 2a3fcc55e98..d9aa43d78bc 100644 --- a/Documentation/DMA-API.txt +++ b/Documentation/DMA-API.txt @@ -609,3 +609,109 @@ size is the size (and should be a page-sized multiple). The return value will be either a pointer to the processor virtual address of the memory, or an error (via PTR_ERR()) if any part of the region is occupied. + +Part III - Debug drivers use of the DMA-API +------------------------------------------- + +The DMA-API as described above as some constraints. DMA addresses must be +released with the corresponding function with the same size for example. With +the advent of hardware IOMMUs it becomes more and more important that drivers +do not violate those constraints. In the worst case such a violation can +result in data corruption up to destroyed filesystems. + +To debug drivers and find bugs in the usage of the DMA-API checking code can +be compiled into the kernel which will tell the developer about those +violations. If your architecture supports it you can select the "Enable +debugging of DMA-API usage" option in your kernel configuration. Enabling this +option has a performance impact. Do not enable it in production kernels. + +If you boot the resulting kernel will contain code which does some bookkeeping +about what DMA memory was allocated for which device. If this code detects an +error it prints a warning message with some details into your kernel log. An +example warning message may look like this: + +------------[ cut here ]------------ +WARNING: at /data2/repos/linux-2.6-iommu/lib/dma-debug.c:448 + check_unmap+0x203/0x490() +Hardware name: +forcedeth 0000:00:08.0: DMA-API: device driver frees DMA memory with wrong + function [device address=0x00000000640444be] [size=66 bytes] [mapped as +single] [unmapped as page] +Modules linked in: nfsd exportfs bridge stp llc r8169 +Pid: 0, comm: swapper Tainted: G W 2.6.28-dmatest-09289-g8bb99c0 #1 +Call Trace: + [] warn_slowpath+0xf2/0x130 + [] _spin_unlock+0x10/0x30 + [] usb_hcd_link_urb_to_ep+0x75/0xc0 + [] _spin_unlock_irqrestore+0x12/0x40 + [] ohci_urb_enqueue+0x19f/0x7c0 + [] queue_work+0x56/0x60 + [] enqueue_task_fair+0x20/0x50 + [] usb_hcd_submit_urb+0x379/0xbc0 + [] cpumask_next_and+0x23/0x40 + [] find_busiest_group+0x207/0x8a0 + [] _spin_lock_irqsave+0x1f/0x50 + [] check_unmap+0x203/0x490 + [] debug_dma_unmap_page+0x49/0x50 + [] nv_tx_done_optimized+0xc6/0x2c0 + [] nv_nic_irq_optimized+0x73/0x2b0 + [] handle_IRQ_event+0x34/0x70 + [] handle_edge_irq+0xc9/0x150 + [] do_IRQ+0xcb/0x1c0 + [] ret_from_intr+0x0/0xa + <4>---[ end trace f6435a98e2a38c0e ]--- + +The driver developer can find the driver and the device including a stacktrace +of the DMA-API call which caused this warning. + +Per default only the first error will result in a warning message. All other +errors will only silently counted. This limitation exist to prevent the code +from flooding your kernel log. To support debugging a device driver this can +be disabled via debugfs. See the debugfs interface documentation below for +details. + +The debugfs directory for the DMA-API debugging code is called dma-api/. In +this directory the following files can currently be found: + + dma-api/all_errors This file contains a numeric value. If this + value is not equal to zero the debugging code + will print a warning for every error it finds + into the kernel log. Be carefull with this + option. It can easily flood your logs. + + dma-api/disabled This read-only file contains the character 'Y' + if the debugging code is disabled. This can + happen when it runs out of memory or if it was + disabled at boot time + + dma-api/error_count This file is read-only and shows the total + numbers of errors found. + + dma-api/num_errors The number in this file shows how many + warnings will be printed to the kernel log + before it stops. This number is initialized to + one at system boot and be set by writing into + this file + + dma-api/min_free_entries + This read-only file can be read to get the + minimum number of free dma_debug_entries the + allocator has ever seen. If this value goes + down to zero the code will disable itself + because it is not longer reliable. + + dma-api/num_free_entries + The current number of free dma_debug_entries + in the allocator. + +If you have this code compiled into your kernel it will be enabled by default. +If you want to boot without the bookkeeping anyway you can provide +'dma_debug=off' as a boot parameter. This will disable DMA-API debugging. +Notice that you can not enable it again at runtime. You have to reboot to do +so. + +When the code disables itself at runtime this is most likely because it ran +out of dma_debug_entries. These entries are preallocated at boot. The number +of preallocated entries is defined per architecture. If it is too low for you +boot with 'dma_debug_entries=' to overwrite the +architectural default. -- cgit v1.2.3 From 9bdd8d40c8c59435664af6049dabe24b7779b203 Mon Sep 17 00:00:00 2001 From: Brian Haley Date: Wed, 18 Mar 2009 18:22:48 -0700 Subject: ipv6: Fix incorrect disable_ipv6 behavior Fix the behavior of allowing both sysctl and addrconf_dad_failure() to set the disable_ipv6 parameter without any bad side-effects. If DAD fails and accept_dad > 1, we will still set disable_ipv6=1, but then instead of allowing an RA to add an address then immediately fail DAD, we simply don't allow the address to be added in the first place. This also lets the user set this flag and disable all IPv6 addresses on the interface, or on the entire system. Signed-off-by: Brian Haley Signed-off-by: David S. Miller --- Documentation/networking/ip-sysctl.txt | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index 7185e4c41e5..ec5de02f543 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -1043,7 +1043,9 @@ max_addresses - INTEGER Default: 16 disable_ipv6 - BOOLEAN - Disable IPv6 operation. + Disable IPv6 operation. If accept_dad is set to 2, this value + will be dynamically set to TRUE if DAD fails for the link-local + address. Default: FALSE (enable IPv6 operation) accept_dad - INTEGER -- cgit v1.2.3 From 1cc0ca26c57221f5aa0f49a311a8fc83413dfe97 Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Wed, 14 Jan 2009 10:04:36 -0700 Subject: PCI/x86: document pci=earlydump argument Document the "pci=earlydump" argument. This currently only works on x86. Signed-off-by: Bjorn Helgaas Signed-off-by: Jesse Barnes --- Documentation/kernel-parameters.txt | 2 ++ 1 file changed, 2 insertions(+) (limited to 'Documentation') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 54f21a5c262..c7c441e7930 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1659,6 +1659,8 @@ and is between 256 and 4096 characters. It is defined in the file See also Documentation/blockdev/paride.txt. pci=option[,option...] [PCI] various PCI subsystem options: + earlydump [X86] dump PCI config space before the kernel + changes anything off [X86] don't probe for the PCI bus bios [X86-32] force use of PCI BIOS, don't access the hardware directly. Use this if your machine -- cgit v1.2.3 From 0994375e9614f78657031e04e30019b9cdb62795 Mon Sep 17 00:00:00 2001 From: Chris Wright Date: Mon, 23 Feb 2009 21:52:23 -0800 Subject: PCI: add remove_id sysfs entry This adds a remove_id sysfs entry to allow users of new_id to later remove the added dynid. One use case is management tools that want to dynamically bind/unbind devices to pci-stub driver while devices are assigned to KVM guests. Rather than having to track which driver was originally bound to the driver, a mangement tool can simply: Guest uses device Signed-off-by: Chris Wright Signed-off-by: Jesse Barnes --- Documentation/ABI/testing/sysfs-bus-pci | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) (limited to 'Documentation') diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci index e638e15a889..3d29793a0ea 100644 --- a/Documentation/ABI/testing/sysfs-bus-pci +++ b/Documentation/ABI/testing/sysfs-bus-pci @@ -41,6 +41,22 @@ Description: for the device and attempt to bind to it. For example: # echo "8086 10f5" > /sys/bus/pci/drivers/foo/new_id +What: /sys/bus/pci/drivers/.../remove_id +Date: February 2009 +Contact: Chris Wright +Description: + Writing a device ID to this file will remove an ID + that was dynamically added via the new_id sysfs entry. + The format for the device ID is: + VVVV DDDD SVVV SDDD CCCC MMMM. That is Vendor ID, Device + ID, Subsystem Vendor ID, Subsystem Device ID, Class, + and Class Mask. The Vendor ID and Device ID fields are + required, the rest are optional. After successfully + removing an ID, the driver will no longer support the + device. This is useful to ensure auto probing won't + match the driver to the device. For example: + # echo "8086 10f5" > /sys/bus/pci/drivers/foo/remove_id + What: /sys/bus/pci/devices/.../vpd Date: February 2008 Contact: Ben Hutchings -- cgit v1.2.3 From c41ade2ee1dc146d2de2ee470a87cd6b878a08f4 Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Tue, 17 Mar 2009 08:54:05 -0400 Subject: Rewrite MSI-HOWTO I didn't find the previous version very useful, so I rewrote it. Signed-off-by: Matthew Wilcox Reviewed-by: Randy Dunlap Reviewed-by: Grant Grundler Signed-off-by: Jesse Barnes --- Documentation/PCI/MSI-HOWTO.txt | 758 +++++++++++++++------------------------- 1 file changed, 277 insertions(+), 481 deletions(-) (limited to 'Documentation') diff --git a/Documentation/PCI/MSI-HOWTO.txt b/Documentation/PCI/MSI-HOWTO.txt index 256defd7e17..1c02431f1d1 100644 --- a/Documentation/PCI/MSI-HOWTO.txt +++ b/Documentation/PCI/MSI-HOWTO.txt @@ -4,506 +4,302 @@ Revised Feb 12, 2004 by Martine Silbermann email: Martine.Silbermann@hp.com Revised Jun 25, 2004 by Tom L Nguyen + Revised Jul 9, 2008 by Matthew Wilcox + Copyright 2003, 2008 Intel Corporation 1. About this guide -This guide describes the basics of Message Signaled Interrupts (MSI), -the advantages of using MSI over traditional interrupt mechanisms, -and how to enable your driver to use MSI or MSI-X. Also included is -a Frequently Asked Questions (FAQ) section. - -1.1 Terminology - -PCI devices can be single-function or multi-function. In either case, -when this text talks about enabling or disabling MSI on a "device -function," it is referring to one specific PCI device and function and -not to all functions on a PCI device (unless the PCI device has only -one function). - -2. Copyright 2003 Intel Corporation - -3. What is MSI/MSI-X? - -Message Signaled Interrupt (MSI), as described in the PCI Local Bus -Specification Revision 2.3 or later, is an optional feature, and a -required feature for PCI Express devices. MSI enables a device function -to request service by sending an Inbound Memory Write on its PCI bus to -the FSB as a Message Signal Interrupt transaction. Because MSI is -generated in the form of a Memory Write, all transaction conditions, -such as a Retry, Master-Abort, Target-Abort or normal completion, are -supported. - -A PCI device that supports MSI must also support pin IRQ assertion -interrupt mechanism to provide backward compatibility for systems that -do not support MSI. In systems which support MSI, the bus driver is -responsible for initializing the message address and message data of -the device function's MSI/MSI-X capability structure during device -initial configuration. - -An MSI capable device function indicates MSI support by implementing -the MSI/MSI-X capability structure in its PCI capability list. The -device function may implement both the MSI capability structure and -the MSI-X capability structure; however, the bus driver should not -enable both. - -The MSI capability structure contains Message Control register, -Message Address register and Message Data register. These registers -provide the bus driver control over MSI. The Message Control register -indicates the MSI capability supported by the device. The Message -Address register specifies the target address and the Message Data -register specifies the characteristics of the message. To request -service, the device function writes the content of the Message Data -register to the target address. The device and its software driver -are prohibited from writing to these registers. - -The MSI-X capability structure is an optional extension to MSI. It -uses an independent and separate capability structure. There are -some key advantages to implementing the MSI-X capability structure -over the MSI capability structure as described below. - - - Support a larger maximum number of vectors per function. - - - Provide the ability for system software to configure - each vector with an independent message address and message - data, specified by a table that resides in Memory Space. - - - MSI and MSI-X both support per-vector masking. Per-vector - masking is an optional extension of MSI but a required - feature for MSI-X. Per-vector masking provides the kernel the - ability to mask/unmask a single MSI while running its - interrupt service routine. If per-vector masking is - not supported, then the device driver should provide the - hardware/software synchronization to ensure that the device - generates MSI when the driver wants it to do so. - -4. Why use MSI? - -As a benefit to the simplification of board design, MSI allows board -designers to remove out-of-band interrupt routing. MSI is another -step towards a legacy-free environment. - -Due to increasing pressure on chipset and processor packages to -reduce pin count, the need for interrupt pins is expected to -diminish over time. Devices, due to pin constraints, may implement -messages to increase performance. - -PCI Express endpoints uses INTx emulation (in-band messages) instead -of IRQ pin assertion. Using INTx emulation requires interrupt -sharing among devices connected to the same node (PCI bridge) while -MSI is unique (non-shared) and does not require BIOS configuration -support. As a result, the PCI Express technology requires MSI -support for better interrupt performance. - -Using MSI enables the device functions to support two or more -vectors, which can be configured to target different CPUs to -increase scalability. - -5. Configuring a driver to use MSI/MSI-X - -By default, the kernel will not enable MSI/MSI-X on all devices that -support this capability. The CONFIG_PCI_MSI kernel option -must be selected to enable MSI/MSI-X support. - -5.1 Including MSI/MSI-X support into the kernel - -To allow MSI/MSI-X capable device drivers to selectively enable -MSI/MSI-X (using pci_enable_msi()/pci_enable_msix() as described -below), the VECTOR based scheme needs to be enabled by setting -CONFIG_PCI_MSI during kernel config. - -Since the target of the inbound message is the local APIC, providing -CONFIG_X86_LOCAL_APIC must be enabled as well as CONFIG_PCI_MSI. - -5.2 Configuring for MSI support - -Due to the non-contiguous fashion in vector assignment of the -existing Linux kernel, this version does not support multiple -messages regardless of a device function is capable of supporting -more than one vector. To enable MSI on a device function's MSI -capability structure requires a device driver to call the function -pci_enable_msi() explicitly. - -5.2.1 API pci_enable_msi +This guide describes the basics of Message Signaled Interrupts (MSIs), +the advantages of using MSI over traditional interrupt mechanisms, how +to change your driver to use MSI or MSI-X and some basic diagnostics to +try if a device doesn't support MSIs. + + +2. What are MSIs? + +A Message Signaled Interrupt is a write from the device to a special +address which causes an interrupt to be received by the CPU. + +The MSI capability was first specified in PCI 2.2 and was later enhanced +in PCI 3.0 to allow each interrupt to be masked individually. The MSI-X +capability was also introduced with PCI 3.0. It supports more interrupts +per device than MSI and allows interrupts to be independently configured. + +Devices may support both MSI and MSI-X, but only one can be enabled at +a time. + + +3. Why use MSIs? + +There are three reasons why using MSIs can give an advantage over +traditional pin-based interrupts. + +Pin-based PCI interrupts are often shared amongst several devices. +To support this, the kernel must call each interrupt handler associated +with an interrupt, which leads to reduced performance for the system as +a whole. MSIs are never shared, so this problem cannot arise. + +When a device writes data to memory, then raises a pin-based interrupt, +it is possible that the interrupt may arrive before all the data has +arrived in memory (this becomes more likely with devices behind PCI-PCI +bridges). In order to ensure that all the data has arrived in memory, +the interrupt handler must read a register on the device which raised +the interrupt. PCI transaction ordering rules require that all the data +arrives in memory before the value can be returned from the register. +Using MSIs avoids this problem as the interrupt-generating write cannot +pass the data writes, so by the time the interrupt is raised, the driver +knows that all the data has arrived in memory. + +PCI devices can only support a single pin-based interrupt per function. +Often drivers have to query the device to find out what event has +occurred, slowing down interrupt handling for the common case. With +MSIs, a device can support more interrupts, allowing each interrupt +to be specialised to a different purpose. One possible design gives +infrequent conditions (such as errors) their own interrupt which allows +the driver to handle the normal interrupt handling path more efficiently. +Other possible designs include giving one interrupt to each packet queue +in a network card or each port in a storage controller. + + +4. How to use MSIs + +PCI devices are initialised to use pin-based interrupts. The device +driver has to set up the device to use MSI or MSI-X. Not all machines +support MSIs correctly, and for those machines, the APIs described below +will simply fail and the device will continue to use pin-based interrupts. + +4.1 Include kernel support for MSIs + +To support MSI or MSI-X, the kernel must be built with the CONFIG_PCI_MSI +option enabled. This option is only available on some architectures, +and it may depend on some other options also being set. For example, +on x86, you must also enable X86_UP_APIC or SMP in order to see the +CONFIG_PCI_MSI option. + +4.2 Using MSI + +Most of the hard work is done for the driver in the PCI layer. It simply +has to request that the PCI layer set up the MSI capability for this +device. + +4.2.1 pci_enable_msi int pci_enable_msi(struct pci_dev *dev) -With this new API, a device driver that wants to have MSI -enabled on its device function must call this API to enable MSI. -A successful call will initialize the MSI capability structure -with ONE vector, regardless of whether a device function is -capable of supporting multiple messages. This vector replaces the -pre-assigned dev->irq with a new MSI vector. To avoid a conflict -of the new assigned vector with existing pre-assigned vector requires -a device driver to call this API before calling request_irq(). +A successful call will allocate ONE interrupt to the device, regardless +of how many MSIs the device supports. The device will be switched from +pin-based interrupt mode to MSI mode. The dev->irq number is changed +to a new number which represents the message signaled interrupt. +This function should be called before the driver calls request_irq() +since enabling MSIs disables the pin-based IRQ and the driver will not +receive interrupts on the old interrupt. -5.2.2 API pci_disable_msi +4.2.2 pci_disable_msi void pci_disable_msi(struct pci_dev *dev) -This API should always be used to undo the effect of pci_enable_msi() -when a device driver is unloading. This API restores dev->irq with -the pre-assigned IOAPIC vector and switches a device's interrupt -mode to PCI pin-irq assertion/INTx emulation mode. - -Note that a device driver should always call free_irq() on the MSI vector -that it has done request_irq() on before calling this API. Failure to do -so results in a BUG_ON() and a device will be left with MSI enabled and -leaks its vector. - -5.2.3 MSI mode vs. legacy mode diagram - -The below diagram shows the events which switch the interrupt -mode on the MSI-capable device function between MSI mode and -PIN-IRQ assertion mode. - - ------------ pci_enable_msi ------------------------ - | | <=============== | | - | MSI MODE | | PIN-IRQ ASSERTION MODE | - | | ===============> | | - ------------ pci_disable_msi ------------------------ - - -Figure 1. MSI Mode vs. Legacy Mode - -In Figure 1, a device operates by default in legacy mode. Legacy -in this context means PCI pin-irq assertion or PCI-Express INTx -emulation. A successful MSI request (using pci_enable_msi()) switches -a device's interrupt mode to MSI mode. A pre-assigned IOAPIC vector -stored in dev->irq will be saved by the PCI subsystem and a new -assigned MSI vector will replace dev->irq. - -To return back to its default mode, a device driver should always call -pci_disable_msi() to undo the effect of pci_enable_msi(). Note that a -device driver should always call free_irq() on the MSI vector it has -done request_irq() on before calling pci_disable_msi(). Failure to do -so results in a BUG_ON() and a device will be left with MSI enabled and -leaks its vector. Otherwise, the PCI subsystem restores a device's -dev->irq with a pre-assigned IOAPIC vector and marks the released -MSI vector as unused. - -Once being marked as unused, there is no guarantee that the PCI -subsystem will reserve this MSI vector for a device. Depending on -the availability of current PCI vector resources and the number of -MSI/MSI-X requests from other drivers, this MSI may be re-assigned. - -For the case where the PCI subsystem re-assigns this MSI vector to -another driver, a request to switch back to MSI mode may result -in being assigned a different MSI vector or a failure if no more -vectors are available. - -5.3 Configuring for MSI-X support - -Due to the ability of the system software to configure each vector of -the MSI-X capability structure with an independent message address -and message data, the non-contiguous fashion in vector assignment of -the existing Linux kernel has no impact on supporting multiple -messages on an MSI-X capable device functions. To enable MSI-X on -a device function's MSI-X capability structure requires its device -driver to call the function pci_enable_msix() explicitly. - -The function pci_enable_msix(), once invoked, enables either -all or nothing, depending on the current availability of PCI vector -resources. If the PCI vector resources are available for the number -of vectors requested by a device driver, this function will configure -the MSI-X table of the MSI-X capability structure of a device with -requested messages. To emphasize this reason, for example, a device -may be capable for supporting the maximum of 32 vectors while its -software driver usually may request 4 vectors. It is recommended -that the device driver should call this function once during the -initialization phase of the device driver. - -Unlike the function pci_enable_msi(), the function pci_enable_msix() -does not replace the pre-assigned IOAPIC dev->irq with a new MSI -vector because the PCI subsystem writes the 1:1 vector-to-entry mapping -into the field vector of each element contained in a second argument. -Note that the pre-assigned IOAPIC dev->irq is valid only if the device -operates in PIN-IRQ assertion mode. In MSI-X mode, any attempt at -using dev->irq by the device driver to request for interrupt service -may result in unpredictable behavior. - -For each MSI-X vector granted, a device driver is responsible for calling -other functions like request_irq(), enable_irq(), etc. to enable -this vector with its corresponding interrupt service handler. It is -a device driver's choice to assign all vectors with the same -interrupt service handler or each vector with a unique interrupt -service handler. - -5.3.1 Handling MMIO address space of MSI-X Table - -The PCI 3.0 specification has implementation notes that MMIO address -space for a device's MSI-X structure should be isolated so that the -software system can set different pages for controlling accesses to the -MSI-X structure. The implementation of MSI support requires the PCI -subsystem, not a device driver, to maintain full control of the MSI-X -table/MSI-X PBA (Pending Bit Array) and MMIO address space of the MSI-X -table/MSI-X PBA. A device driver should not access the MMIO address -space of the MSI-X table/MSI-X PBA. - -5.3.2 API pci_enable_msix - -int pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries, int nvec) +This function should be used to undo the effect of pci_enable_msi(). +Calling it restores dev->irq to the pin-based interrupt number and frees +the previously allocated message signaled interrupt(s). The interrupt +may subsequently be assigned to another device, so drivers should not +cache the value of dev->irq. -This API enables a device driver to request the PCI subsystem -to enable MSI-X messages on its hardware device. Depending on -the availability of PCI vectors resources, the PCI subsystem enables -either all or none of the requested vectors. +A device driver must always call free_irq() on the interrupt(s) +for which it has called request_irq() before calling this function. +Failure to do so will result in a BUG_ON(), the device will be left with +MSI enabled and will leak its vector. -Argument 'dev' points to the device (pci_dev) structure. +4.3 Using MSI-X -Argument 'entries' is a pointer to an array of msix_entry structs. -The number of entries is indicated in argument 'nvec'. -struct msix_entry is defined in /driver/pci/msi.h: +The MSI-X capability is much more flexible than the MSI capability. +It supports up to 2048 interrupts, each of which can be controlled +independently. To support this flexibility, drivers must use an array of +`struct msix_entry': struct msix_entry { u16 vector; /* kernel uses to write alloc vector */ u16 entry; /* driver uses to specify entry */ }; -A device driver is responsible for initializing the field 'entry' of -each element with a unique entry supported by MSI-X table. Otherwise, --EINVAL will be returned as a result. A successful return of zero -indicates the PCI subsystem completed initializing each of the requested -entries of the MSI-X table with message address and message data. -Last but not least, the PCI subsystem will write the 1:1 -vector-to-entry mapping into the field 'vector' of each element. A -device driver is responsible for keeping track of allocated MSI-X -vectors in its internal data structure. - -A return of zero indicates that the number of MSI-X vectors was -successfully allocated. A return of greater than zero indicates -MSI-X vector shortage. Or a return of less than zero indicates -a failure. This failure may be a result of duplicate entries -specified in second argument, or a result of no available vector, -or a result of failing to initialize MSI-X table entries. - -5.3.3 API pci_disable_msix +This allows for the device to use these interrupts in a sparse fashion; +for example it could use interrupts 3 and 1027 and allocate only a +two-element array. The driver is expected to fill in the 'entry' value +in each element of the array to indicate which entries it wants the kernel +to assign interrupts for. It is invalid to fill in two entries with the +same number. + +4.3.1 pci_enable_msix + +int pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries, int nvec) + +Calling this function asks the PCI subsystem to allocate 'nvec' MSIs. +The 'entries' argument is a pointer to an array of msix_entry structs +which should be at least 'nvec' entries in size. On success, the +function will return 0 and the device will have been switched into +MSI-X interrupt mode. The 'vector' elements in each entry will have +been filled in with the interrupt number. The driver should then call +request_irq() for each 'vector' that it decides to use. + +If this function returns a negative number, it indicates an error and +the driver should not attempt to allocate any more MSI-X interrupts for +this device. If it returns a positive number, it indicates the maximum +number of interrupt vectors that could have been allocated. + +This function, in contrast with pci_enable_msi(), does not adjust +dev->irq. The device will not generate interrupts for this interrupt +number once MSI-X is enabled. The device driver is responsible for +keeping track of the interrupts assigned to the MSI-X vectors so it can +free them again later. + +Device drivers should normally call this function once per device +during the initialization phase. + +4.3.2 pci_disable_msix void pci_disable_msix(struct pci_dev *dev) -This API should always be used to undo the effect of pci_enable_msix() -when a device driver is unloading. Note that a device driver should -always call free_irq() on all MSI-X vectors it has done request_irq() -on before calling this API. Failure to do so results in a BUG_ON() and -a device will be left with MSI-X enabled and leaks its vectors. - -5.3.4 MSI-X mode vs. legacy mode diagram - -The below diagram shows the events which switch the interrupt -mode on the MSI-X capable device function between MSI-X mode and -PIN-IRQ assertion mode (legacy). - - ------------ pci_enable_msix(,,n) ------------------------ - | | <=============== | | - | MSI-X MODE | | PIN-IRQ ASSERTION MODE | - | | ===============> | | - ------------ pci_disable_msix ------------------------ - -Figure 2. MSI-X Mode vs. Legacy Mode - -In Figure 2, a device operates by default in legacy mode. A -successful MSI-X request (using pci_enable_msix()) switches a -device's interrupt mode to MSI-X mode. A pre-assigned IOAPIC vector -stored in dev->irq will be saved by the PCI subsystem; however, -unlike MSI mode, the PCI subsystem will not replace dev->irq with -assigned MSI-X vector because the PCI subsystem already writes the 1:1 -vector-to-entry mapping into the field 'vector' of each element -specified in second argument. - -To return back to its default mode, a device driver should always call -pci_disable_msix() to undo the effect of pci_enable_msix(). Note that -a device driver should always call free_irq() on all MSI-X vectors it -has done request_irq() on before calling pci_disable_msix(). Failure -to do so results in a BUG_ON() and a device will be left with MSI-X -enabled and leaks its vectors. Otherwise, the PCI subsystem switches a -device function's interrupt mode from MSI-X mode to legacy mode and -marks all allocated MSI-X vectors as unused. - -Once being marked as unused, there is no guarantee that the PCI -subsystem will reserve these MSI-X vectors for a device. Depending on -the availability of current PCI vector resources and the number of -MSI/MSI-X requests from other drivers, these MSI-X vectors may be -re-assigned. - -For the case where the PCI subsystem re-assigned these MSI-X vectors -to other drivers, a request to switch back to MSI-X mode may result -being assigned with another set of MSI-X vectors or a failure if no -more vectors are available. - -5.4 Handling function implementing both MSI and MSI-X capabilities - -For the case where a function implements both MSI and MSI-X -capabilities, the PCI subsystem enables a device to run either in MSI -mode or MSI-X mode but not both. A device driver determines whether it -wants MSI or MSI-X enabled on its hardware device. Once a device -driver requests for MSI, for example, it is prohibited from requesting -MSI-X; in other words, a device driver is not permitted to ping-pong -between MSI mod MSI-X mode during a run-time. - -5.5 Hardware requirements for MSI/MSI-X support - -MSI/MSI-X support requires support from both system hardware and -individual hardware device functions. - -5.5.1 Required x86 hardware support - -Since the target of MSI address is the local APIC CPU, enabling -MSI/MSI-X support in the Linux kernel is dependent on whether existing -system hardware supports local APIC. Users should verify that their -system supports local APIC operation by testing that it runs when -CONFIG_X86_LOCAL_APIC=y. - -In SMP environment, CONFIG_X86_LOCAL_APIC is automatically set; -however, in UP environment, users must manually set -CONFIG_X86_LOCAL_APIC. Once CONFIG_X86_LOCAL_APIC=y, setting -CONFIG_PCI_MSI enables the VECTOR based scheme and the option for -MSI-capable device drivers to selectively enable MSI/MSI-X. - -Note that CONFIG_X86_IO_APIC setting is irrelevant because MSI/MSI-X -vector is allocated new during runtime and MSI/MSI-X support does not -depend on BIOS support. This key independency enables MSI/MSI-X -support on future IOxAPIC free platforms. - -5.5.2 Device hardware support - -The hardware device function supports MSI by indicating the -MSI/MSI-X capability structure on its PCI capability list. By -default, this capability structure will not be initialized by -the kernel to enable MSI during the system boot. In other words, -the device function is running on its default pin assertion mode. -Note that in many cases the hardware supporting MSI have bugs, -which may result in system hangs. The software driver of specific -MSI-capable hardware is responsible for deciding whether to call -pci_enable_msi or not. A return of zero indicates the kernel -successfully initialized the MSI/MSI-X capability structure of the -device function. The device function is now running on MSI/MSI-X mode. - -5.6 How to tell whether MSI/MSI-X is enabled on device function - -At the driver level, a return of zero from the function call of -pci_enable_msi()/pci_enable_msix() indicates to a device driver that -its device function is initialized successfully and ready to run in -MSI/MSI-X mode. - -At the user level, users can use the command 'cat /proc/interrupts' -to display the vectors allocated for devices and their interrupt -MSI/MSI-X modes ("PCI-MSI"/"PCI-MSI-X"). Below shows MSI mode is -enabled on a SCSI Adaptec 39320D Ultra320 controller. - - CPU0 CPU1 - 0: 324639 0 IO-APIC-edge timer - 1: 1186 0 IO-APIC-edge i8042 - 2: 0 0 XT-PIC cascade - 12: 2797 0 IO-APIC-edge i8042 - 14: 6543 0 IO-APIC-edge ide0 - 15: 1 0 IO-APIC-edge ide1 -169: 0 0 IO-APIC-level uhci-hcd -185: 0 0 IO-APIC-level uhci-hcd -193: 138 10 PCI-MSI aic79xx -201: 30 0 PCI-MSI aic79xx -225: 30 0 IO-APIC-level aic7xxx -233: 30 0 IO-APIC-level aic7xxx -NMI: 0 0 -LOC: 324553 325068 -ERR: 0 -MIS: 0 - -6. MSI quirks - -Several PCI chipsets or devices are known to not support MSI. -The PCI stack provides 3 possible levels of MSI disabling: -* on a single device -* on all devices behind a specific bridge -* globally - -6.1. Disabling MSI on a single device - -Under some circumstances it might be required to disable MSI on a -single device. This may be achieved by either not calling pci_enable_msi() -or all, or setting the pci_dev->no_msi flag before (most of the time -in a quirk). - -6.2. Disabling MSI below a bridge - -The vast majority of MSI quirks are required by PCI bridges not -being able to route MSI between busses. In this case, MSI have to be -disabled on all devices behind this bridge. It is achieves by setting -the PCI_BUS_FLAGS_NO_MSI flag in the pci_bus->bus_flags of the bridge -subordinate bus. There is no need to set the same flag on bridges that -are below the broken bridge. When pci_enable_msi() is called to enable -MSI on a device, pci_msi_supported() takes care of checking the NO_MSI -flag in all parent busses of the device. - -Some bridges actually support dynamic MSI support enabling/disabling -by changing some bits in their PCI configuration space (especially -the Hypertransport chipsets such as the nVidia nForce and Serverworks -HT2000). It may then be required to update the NO_MSI flag on the -corresponding devices in the sysfs hierarchy. To enable MSI support -on device "0000:00:0e", do: - - echo 1 > /sys/bus/pci/devices/0000:00:0e/msi_bus - -To disable MSI support, echo 0 instead of 1. Note that it should be -used with caution since changing this value might break interrupts. - -6.3. Disabling MSI globally - -Some extreme cases may require to disable MSI globally on the system. -For now, the only known case is a Serverworks PCI-X chipsets (MSI are -not supported on several busses that are not all connected to the -chipset in the Linux PCI hierarchy). In the vast majority of other -cases, disabling only behind a specific bridge is enough. - -For debugging purpose, the user may also pass pci=nomsi on the kernel -command-line to explicitly disable MSI globally. But, once the appro- -priate quirks are added to the kernel, this option should not be -required anymore. - -6.4. Finding why MSI cannot be enabled on a device - -Assuming that MSI are not enabled on a device, you should look at -dmesg to find messages that quirks may output when disabling MSI -on some devices, some bridges or even globally. -Then, lspci -t gives the list of bridges above a device. Reading -/sys/bus/pci/devices/0000:00:0e/msi_bus will tell you whether MSI -are enabled (1) or disabled (0). In 0 is found in a single bridge -msi_bus file above the device, MSI cannot be enabled. - -7. FAQ - -Q1. Are there any limitations on using the MSI? - -A1. If the PCI device supports MSI and conforms to the -specification and the platform supports the APIC local bus, -then using MSI should work. - -Q2. Will it work on all the Pentium processors (P3, P4, Xeon, -AMD processors)? In P3 IPI's are transmitted on the APIC local -bus and in P4 and Xeon they are transmitted on the system -bus. Are there any implications with this? - -A2. MSI support enables a PCI device sending an inbound -memory write (0xfeexxxxx as target address) on its PCI bus -directly to the FSB. Since the message address has a -redirection hint bit cleared, it should work. - -Q3. The target address 0xfeexxxxx will be translated by the -Host Bridge into an interrupt message. Are there any -limitations on the chipsets such as Intel 8xx, Intel e7xxx, -or VIA? - -A3. If these chipsets support an inbound memory write with -target address set as 0xfeexxxxx, as conformed to PCI -specification 2.3 or latest, then it should work. - -Q4. From the driver point of view, if the MSI is lost because -of errors occurring during inbound memory write, then it may -wait forever. Is there a mechanism for it to recover? - -A4. Since the target of the transaction is an inbound memory -write, all transaction termination conditions (Retry, -Master-Abort, Target-Abort, or normal completion) are -supported. A device sending an MSI must abide by all the PCI -rules and conditions regarding that inbound memory write. So, -if a retry is signaled it must retry, etc... We believe that -the recommendation for Abort is also a retry (refer to PCI -specification 2.3 or latest). +This API should be used to undo the effect of pci_enable_msix(). It frees +the previously allocated message signaled interrupts. The interrupts may +subsequently be assigned to another device, so drivers should not cache +the value of the 'vector' elements over a call to pci_disable_msix(). + +A device driver must always call free_irq() on the interrupt(s) +for which it has called request_irq() before calling this function. +Failure to do so will result in a BUG_ON(), the device will be left with +MSI enabled and will leak its vector. + +4.3.3 The MSI-X Table + +The MSI-X capability specifies a BAR and offset within that BAR for the +MSI-X Table. This address is mapped by the PCI subsystem, and should not +be accessed directly by the device driver. If the driver wishes to +mask or unmask an interrupt, it should call disable_irq() / enable_irq(). + +4.4 Handling devices implementing both MSI and MSI-X capabilities + +If a device implements both MSI and MSI-X capabilities, it can +run in either MSI mode or MSI-X mode but not both simultaneously. +This is a requirement of the PCI spec, and it is enforced by the +PCI layer. Calling pci_enable_msi() when MSI-X is already enabled or +pci_enable_msix() when MSI is already enabled will result in an error. +If a device driver wishes to switch between MSI and MSI-X at runtime, +it must first quiesce the device, then switch it back to pin-interrupt +mode, before calling pci_enable_msi() or pci_enable_msix() and resuming +operation. This is not expected to be a common operation but may be +useful for debugging or testing during development. + +4.5 Considerations when using MSIs + +4.5.1 Choosing between MSI-X and MSI + +If your device supports both MSI-X and MSI capabilities, you should use +the MSI-X facilities in preference to the MSI facilities. As mentioned +above, MSI-X supports any number of interrupts between 1 and 2048. +In constrast, MSI is restricted to a maximum of 32 interrupts (and +must be a power of two). In addition, the MSI interrupt vectors must +be allocated consecutively, so the system may not be able to allocate +as many vectors for MSI as it could for MSI-X. On some platforms, MSI +interrupts must all be targetted at the same set of CPUs whereas MSI-X +interrupts can all be targetted at different CPUs. + +4.5.2 Spinlocks + +Most device drivers have a per-device spinlock which is taken in the +interrupt handler. With pin-based interrupts or a single MSI, it is not +necessary to disable interrupts (Linux guarantees the same interrupt will +not be re-entered). If a device uses multiple interrupts, the driver +must disable interrupts while the lock is held. If the device sends +a different interrupt, the driver will deadlock trying to recursively +acquire the spinlock. + +There are two solutions. The first is to take the lock with +spin_lock_irqsave() or spin_lock_irq() (see +Documentation/DocBook/kernel-locking). The second is to specify +IRQF_DISABLED to request_irq() so that the kernel runs the entire +interrupt routine with interrupts disabled. + +If your MSI interrupt routine does not hold the lock for the whole time +it is running, the first solution may be best. The second solution is +normally preferred as it avoids making two transitions from interrupt +disabled to enabled and back again. + +4.6 How to tell whether MSI/MSI-X is enabled on a device + +Using 'lspci -v' (as root) may show some devices with "MSI", "Message +Signalled Interrupts" or "MSI-X" capabilities. Each of these capabilities +has an 'Enable' flag which will be followed with either "+" (enabled) +or "-" (disabled). + + +5. MSI quirks + +Several PCI chipsets or devices are known not to support MSIs. +The PCI stack provides three ways to disable MSIs: + +1. globally +2. on all devices behind a specific bridge +3. on a single device + +5.1. Disabling MSIs globally + +Some host chipsets simply don't support MSIs properly. If we're +lucky, the manufacturer knows this and has indicated it in the ACPI +FADT table. In this case, Linux will automatically disable MSIs. +Some boards don't include this information in the table and so we have +to detect them ourselves. The complete list of these is found near the +quirk_disable_all_msi() function in drivers/pci/quirks.c. + +If you have a board which has problems with MSIs, you can pass pci=nomsi +on the kernel command line to disable MSIs on all devices. It would be +in your best interests to report the problem to linux-pci@vger.kernel.org +including a full 'lspci -v' so we can add the quirks to the kernel. + +5.2. Disabling MSIs below a bridge + +Some PCI bridges are not able to route MSIs between busses properly. +In this case, MSIs must be disabled on all devices behind the bridge. + +Some bridges allow you to enable MSIs by changing some bits in their +PCI configuration space (especially the Hypertransport chipsets such +as the nVidia nForce and Serverworks HT2000). As with host chipsets, +Linux mostly knows about them and automatically enables MSIs if it can. +If you have a bridge which Linux doesn't yet know about, you can enable +MSIs in configuration space using whatever method you know works, then +enable MSIs on that bridge by doing: + + echo 1 > /sys/bus/pci/devices/$bridge/msi_bus + +where $bridge is the PCI address of the bridge you've enabled (eg +0000:00:0e.0). + +To disable MSIs, echo 0 instead of 1. Changing this value should be +done with caution as it can break interrupt handling for all devices +below this bridge. + +Again, please notify linux-pci@vger.kernel.org of any bridges that need +special handling. + +5.3. Disabling MSIs on a single device + +Some devices are known to have faulty MSI implementations. Usually this +is handled in the individual device driver but occasionally it's necessary +to handle this with a quirk. Some drivers have an option to disable use +of MSI. While this is a convenient workaround for the driver author, +it is not good practise, and should not be emulated. + +5.4. Finding why MSIs are disabled on a device + +From the above three sections, you can see that there are many reasons +why MSIs may not be enabled for a given device. Your first step should +be to examine your dmesg carefully to determine whether MSIs are enabled +for your machine. You should also check your .config to be sure you +have enabled CONFIG_PCI_MSI. + +Then, 'lspci -t' gives the list of bridges above a device. Reading +/sys/bus/pci/devices/*/msi_bus will tell you whether MSI are enabled (1) +or disabled (0). If 0 is found in any of the msi_bus files belonging +to bridges between the PCI root and the device, MSIs are disabled. + +It is also worth checking the device driver to see whether it supports MSIs. +For example, it may contain calls to pci_enable_msi(), pci_enable_msix() or +pci_enable_msi_block(). -- cgit v1.2.3 From 1c8d7b0a562da06d3ebe83f01b1ed553205d1ae4 Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Tue, 17 Mar 2009 08:54:10 -0400 Subject: PCI MSI: Add support for multiple MSI Add the new API pci_enable_msi_block() to allow drivers to request multiple MSI and reimplement pci_enable_msi in terms of pci_enable_msi_block. Ensure that the architecture back ends don't have to know about multiple MSI. Signed-off-by: Matthew Wilcox Signed-off-by: Jesse Barnes --- Documentation/PCI/MSI-HOWTO.txt | 45 +++++++++++++++++++++++++++++++++++------ 1 file changed, 39 insertions(+), 6 deletions(-) (limited to 'Documentation') diff --git a/Documentation/PCI/MSI-HOWTO.txt b/Documentation/PCI/MSI-HOWTO.txt index 1c02431f1d1..9494f6dc38e 100644 --- a/Documentation/PCI/MSI-HOWTO.txt +++ b/Documentation/PCI/MSI-HOWTO.txt @@ -94,15 +94,48 @@ This function should be called before the driver calls request_irq() since enabling MSIs disables the pin-based IRQ and the driver will not receive interrupts on the old interrupt. -4.2.2 pci_disable_msi +4.2.2 pci_enable_msi_block + +int pci_enable_msi_block(struct pci_dev *dev, int count) + +This variation on the above call allows a device driver to request multiple +MSIs. The MSI specification only allows interrupts to be allocated in +powers of two, up to a maximum of 2^5 (32). + +If this function returns 0, it has succeeded in allocating at least as many +interrupts as the driver requested (it may have allocated more in order +to satisfy the power-of-two requirement). In this case, the function +enables MSI on this device and updates dev->irq to be the lowest of +the new interrupts assigned to it. The other interrupts assigned to +the device are in the range dev->irq to dev->irq + count - 1. + +If this function returns a negative number, it indicates an error and +the driver should not attempt to request any more MSI interrupts for +this device. If this function returns a positive number, it will be +less than 'count' and indicate the number of interrupts that could have +been allocated. In neither case will the irq value have been +updated, nor will the device have been switched into MSI mode. + +The device driver must decide what action to take if +pci_enable_msi_block() returns a value less than the number asked for. +Some devices can make use of fewer interrupts than the maximum they +request; in this case the driver should call pci_enable_msi_block() +again. Note that it is not guaranteed to succeed, even when the +'count' has been reduced to the value returned from a previous call to +pci_enable_msi_block(). This is because there are multiple constraints +on the number of vectors that can be allocated; pci_enable_msi_block() +will return as soon as it finds any constraint that doesn't allow the +call to succeed. + +4.2.3 pci_disable_msi void pci_disable_msi(struct pci_dev *dev) -This function should be used to undo the effect of pci_enable_msi(). -Calling it restores dev->irq to the pin-based interrupt number and frees -the previously allocated message signaled interrupt(s). The interrupt -may subsequently be assigned to another device, so drivers should not -cache the value of dev->irq. +This function should be used to undo the effect of pci_enable_msi() or +pci_enable_msi_block(). Calling it restores dev->irq to the pin-based +interrupt number and frees the previously allocated message signaled +interrupt(s). The interrupt may subsequently be assigned to another +device, so drivers should not cache the value of dev->irq. A device driver must always call free_irq() on the interrupt(s) for which it has called request_irq() before calling this function. -- cgit v1.2.3 From 32a9a682bef2f6fce7026bd94d1ce20028b0e52d Mon Sep 17 00:00:00 2001 From: Yuji Shimada Date: Mon, 16 Mar 2009 17:13:39 +0900 Subject: PCI: allow assignment of memory resources with a specified alignment This patch allows memory resources to be assigned with a specified alignment at boot-time or run-time. The patch is useful when we use PCI pass-through, because page-aligned memory resources are required to securely share PCI resources with guest drivers. If you want to assign the resource at boot time, please set "pci=resource_alignment=" boot parameter. This is format of "pci=resource_alignment=" boot parameter: [@][:]:.[; ...] Specifies alignment and device to reassign aligned memory resources. If is not specified, PAGE_SIZE is used as alignment. PCI-PCI bridge can be specified, if resource windows need to be expanded. This is example: pci=resource_alignment=20@07:00.0;18@0f:00.0;00:1d.7 If you want to assign the resource at run-time, please set "/sys/bus/pci/resource_alignment" file, and hot-remove the device and hot-add the device. For this purpose, fakephp or PCI hotplug interfaces can be used. The format of "/sys/bus/pci/resource_alignment" file is the same with boot parameter. You can use "," instead of ";". For example: # cd /sys/bus/pci # echo -n 20@12:00.0 > resource_alignment # echo 1 > devices/0000:12:00.0/remove # echo 1 > rescan Reviewed-by: Alex Chiang Reviewed-by: Yu Zhao Signed-off-by: Yuji Shimada Signed-off-by: Jesse Barnes --- Documentation/kernel-parameters.txt | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'Documentation') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index c7c441e7930..1754fedc531 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1760,6 +1760,15 @@ and is between 256 and 4096 characters. It is defined in the file cbmemsize=nn[KMG] The fixed amount of bus space which is reserved for the CardBus bridge's memory window. The default value is 64 megabytes. + resource_alignment= + Format: + [@][:]:.[; ...] + Specifies alignment and device to reassign + aligned memory resources. + If is not specified, + PAGE_SIZE is used as alignment. + PCI-PCI bridge can be specified, if resource + windows need to be expanded. pcie_aspm= [PCIE] Forcibly enable or disable PCIe Active State Power Management. -- cgit v1.2.3 From 01db4957179c92fda7d9a06e49b7ae56fb7c925b Mon Sep 17 00:00:00 2001 From: Yu Zhao Date: Fri, 20 Mar 2009 11:25:17 +0800 Subject: PCI: document SR-IOV sysfs entries Reviewed-by: Randy Dunlap Reviewed-by: Matthew Wilcox Signed-off-by: Yu Zhao Signed-off-by: Jesse Barnes --- Documentation/ABI/testing/sysfs-bus-pci | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) (limited to 'Documentation') diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci index 3d29793a0ea..d175a2a5fac 100644 --- a/Documentation/ABI/testing/sysfs-bus-pci +++ b/Documentation/ABI/testing/sysfs-bus-pci @@ -68,3 +68,30 @@ Description: that some devices may have malformatted data. If the underlying VPD has a writable section then the corresponding section of this file will be writable. + +What: /sys/bus/pci/devices/.../virtfnN +Date: March 2009 +Contact: Yu Zhao +Description: + This symbolic link appears when hardware supports the SR-IOV + capability and the Physical Function driver has enabled it. + The symbolic link points to the PCI device sysfs entry of the + Virtual Function whose index is N (0...MaxVFs-1). + +What: /sys/bus/pci/devices/.../dep_link +Date: March 2009 +Contact: Yu Zhao +Description: + This symbolic link appears when hardware supports the SR-IOV + capability and the Physical Function driver has enabled it, + and this device has vendor specific dependencies with others. + The symbolic link points to the PCI device sysfs entry of + Physical Function this device depends on. + +What: /sys/bus/pci/devices/.../physfn +Date: March 2009 +Contact: Yu Zhao +Description: + This symbolic link appears when a device is a Virtual Function. + The symbolic link points to the PCI device sysfs entry of the + Physical Function this device associates with. -- cgit v1.2.3 From 15b49bee3a2b228370194f1b3ebc3db427cc9c94 Mon Sep 17 00:00:00 2001 From: Yu Zhao Date: Fri, 20 Mar 2009 11:25:18 +0800 Subject: PCI: manual for SR-IOV user and driver developer Reviewed-by: Randy Dunlap Reviewed-by: Matthew Wilcox Signed-off-by: Yu Zhao Signed-off-by: Jesse Barnes --- Documentation/DocBook/kernel-api.tmpl | 1 + Documentation/PCI/pci-iov-howto.txt | 99 +++++++++++++++++++++++++++++++++++ 2 files changed, 100 insertions(+) create mode 100644 Documentation/PCI/pci-iov-howto.txt (limited to 'Documentation') diff --git a/Documentation/DocBook/kernel-api.tmpl b/Documentation/DocBook/kernel-api.tmpl index bc962cda650..58c194572c7 100644 --- a/Documentation/DocBook/kernel-api.tmpl +++ b/Documentation/DocBook/kernel-api.tmpl @@ -199,6 +199,7 @@ X!Edrivers/pci/hotplug.c --> !Edrivers/pci/probe.c !Edrivers/pci/rom.c +!Edrivers/pci/iov.c PCI Hotplug Support Library !Edrivers/pci/hotplug/pci_hotplug_core.c diff --git a/Documentation/PCI/pci-iov-howto.txt b/Documentation/PCI/pci-iov-howto.txt new file mode 100644 index 00000000000..fc73ef5d65b --- /dev/null +++ b/Documentation/PCI/pci-iov-howto.txt @@ -0,0 +1,99 @@ + PCI Express I/O Virtualization Howto + Copyright (C) 2009 Intel Corporation + Yu Zhao + + +1. Overview + +1.1 What is SR-IOV + +Single Root I/O Virtualization (SR-IOV) is a PCI Express Extended +capability which makes one physical device appear as multiple virtual +devices. The physical device is referred to as Physical Function (PF) +while the virtual devices are referred to as Virtual Functions (VF). +Allocation of the VF can be dynamically controlled by the PF via +registers encapsulated in the capability. By default, this feature is +not enabled and the PF behaves as traditional PCIe device. Once it's +turned on, each VF's PCI configuration space can be accessed by its own +Bus, Device and Function Number (Routing ID). And each VF also has PCI +Memory Space, which is used to map its register set. VF device driver +operates on the register set so it can be functional and appear as a +real existing PCI device. + +2. User Guide + +2.1 How can I enable SR-IOV capability + +The device driver (PF driver) will control the enabling and disabling +of the capability via API provided by SR-IOV core. If the hardware +has SR-IOV capability, loading its PF driver would enable it and all +VFs associated with the PF. + +2.2 How can I use the Virtual Functions + +The VF is treated as hot-plugged PCI devices in the kernel, so they +should be able to work in the same way as real PCI devices. The VF +requires device driver that is same as a normal PCI device's. + +3. Developer Guide + +3.1 SR-IOV API + +To enable SR-IOV capability: + int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn); + 'nr_virtfn' is number of VFs to be enabled. + +To disable SR-IOV capability: + void pci_disable_sriov(struct pci_dev *dev); + +To notify SR-IOV core of Virtual Function Migration: + irqreturn_t pci_sriov_migration(struct pci_dev *dev); + +3.2 Usage example + +Following piece of code illustrates the usage of the SR-IOV API. + +static int __devinit dev_probe(struct pci_dev *dev, const struct pci_device_id *id) +{ + pci_enable_sriov(dev, NR_VIRTFN); + + ... + + return 0; +} + +static void __devexit dev_remove(struct pci_dev *dev) +{ + pci_disable_sriov(dev); + + ... +} + +static int dev_suspend(struct pci_dev *dev, pm_message_t state) +{ + ... + + return 0; +} + +static int dev_resume(struct pci_dev *dev) +{ + ... + + return 0; +} + +static void dev_shutdown(struct pci_dev *dev) +{ + ... +} + +static struct pci_driver dev_driver = { + .name = "SR-IOV Physical Function driver", + .id_table = dev_id_table, + .probe = dev_probe, + .remove = __devexit_p(dev_remove), + .suspend = dev_suspend, + .resume = dev_resume, + .shutdown = dev_shutdown, +}; -- cgit v1.2.3 From fafad5bf06c3a3bb8b24b28b6f065367e7411872 Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Fri, 20 Mar 2009 15:22:12 +1100 Subject: PCI MSI: Add example request loop to MSI-HOWTO.txt Encourage driver writers to think about supporting a variable number of MSI-X interrupts, and give an example of how to do such a request. Acked-by: Matthew Wilcox Signed-off-by: Michael Ellerman Signed-off-by: Jesse Barnes --- Documentation/PCI/MSI-HOWTO.txt | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/PCI/MSI-HOWTO.txt b/Documentation/PCI/MSI-HOWTO.txt index 9494f6dc38e..dcf7acc720e 100644 --- a/Documentation/PCI/MSI-HOWTO.txt +++ b/Documentation/PCI/MSI-HOWTO.txt @@ -176,7 +176,8 @@ request_irq() for each 'vector' that it decides to use. If this function returns a negative number, it indicates an error and the driver should not attempt to allocate any more MSI-X interrupts for this device. If it returns a positive number, it indicates the maximum -number of interrupt vectors that could have been allocated. +number of interrupt vectors that could have been allocated. See example +below. This function, in contrast with pci_enable_msi(), does not adjust dev->irq. The device will not generate interrupts for this interrupt @@ -187,6 +188,26 @@ free them again later. Device drivers should normally call this function once per device during the initialization phase. +It is ideal if drivers can cope with a variable number of MSI-X interrupts, +there are many reasons why the platform may not be able to provide the +exact number a driver asks for. + +A request loop to achieve that might look like: + +static int foo_driver_enable_msix(struct foo_adapter *adapter, int nvec) +{ + while (nvec >= FOO_DRIVER_MINIMUM_NVEC) { + rc = pci_enable_msix(adapter->pdev, + adapter->msix_entries, nvec); + if (rc > 0) + nvec = rc; + else + return rc; + } + + return -ENOSPC; +} + 4.3.2 pci_disable_msix void pci_disable_msix(struct pci_dev *dev) -- cgit v1.2.3 From 705b1aaa823e800490f157cd9366ad8cff385f5f Mon Sep 17 00:00:00 2001 From: Alex Chiang Date: Fri, 20 Mar 2009 14:56:31 -0600 Subject: PCI: Introduce /sys/bus/pci/rescan This interface allows the user to force a rescan of all PCI buses in system, and rediscover devices that have been removed earlier. pci_bus_attrs implementation from Trent Piepho. Thanks to Vegard Nossum for discovering locking issues with the sysfs interface. Cc: Trent Piepho Signed-off-by: Alex Chiang Signed-off-by: Jesse Barnes --- Documentation/ABI/testing/sysfs-bus-pci | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'Documentation') diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci index d175a2a5fac..e6ad047cb3c 100644 --- a/Documentation/ABI/testing/sysfs-bus-pci +++ b/Documentation/ABI/testing/sysfs-bus-pci @@ -57,6 +57,15 @@ Description: match the driver to the device. For example: # echo "8086 10f5" > /sys/bus/pci/drivers/foo/remove_id +What: /sys/bus/pci/rescan +Date: January 2009 +Contact: Linux PCI developers +Description: + Writing a non-zero value to this attribute will + force a rescan of all PCI buses in the system, and + re-discover previously removed devices. + Depends on CONFIG_HOTPLUG. + What: /sys/bus/pci/devices/.../vpd Date: February 2008 Contact: Ben Hutchings -- cgit v1.2.3 From 77c27c7b49d69d45ccb94e481653f024f1ac6650 Mon Sep 17 00:00:00 2001 From: Alex Chiang Date: Fri, 20 Mar 2009 14:56:36 -0600 Subject: PCI: Introduce /sys/bus/pci/devices/.../remove This patch adds an attribute named "remove" to a PCI device's sysfs directory. Writing a non-zero value to this attribute will remove the PCI device and any children of it. Trent Piepho wrote the original implementation and documentation. Thanks to Vegard Nossum for testing under kmemcheck and finding locking issues with the sysfs interface. Cc: Trent Piepho Tested-by: Vegard Nossum Signed-off-by: Alex Chiang Signed-off-by: Jesse Barnes --- Documentation/ABI/testing/sysfs-bus-pci | 8 ++++++++ Documentation/filesystems/sysfs-pci.txt | 10 ++++++++++ 2 files changed, 18 insertions(+) (limited to 'Documentation') diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci index e6ad047cb3c..daa791a9e85 100644 --- a/Documentation/ABI/testing/sysfs-bus-pci +++ b/Documentation/ABI/testing/sysfs-bus-pci @@ -66,6 +66,14 @@ Description: re-discover previously removed devices. Depends on CONFIG_HOTPLUG. +What: /sys/bus/pci/devices/.../remove +Date: January 2009 +Contact: Linux PCI developers +Description: + Writing a non-zero value to this attribute will + hot-remove the PCI device and any of its children. + Depends on CONFIG_HOTPLUG. + What: /sys/bus/pci/devices/.../vpd Date: February 2008 Contact: Ben Hutchings diff --git a/Documentation/filesystems/sysfs-pci.txt b/Documentation/filesystems/sysfs-pci.txt index 9f8740ca3f3..26e4b8bc53e 100644 --- a/Documentation/filesystems/sysfs-pci.txt +++ b/Documentation/filesystems/sysfs-pci.txt @@ -12,6 +12,7 @@ that support it. For example, a given bus might look like this: | |-- enable | |-- irq | |-- local_cpus + | |-- remove | |-- resource | |-- resource0 | |-- resource1 @@ -36,6 +37,7 @@ files, each with their own function. enable Whether the device is enabled (ascii, rw) irq IRQ number (ascii, ro) local_cpus nearby CPU mask (cpumask, ro) + remove remove device from kernel's list (ascii, wo) resource PCI resource host addresses (ascii, ro) resource0..N PCI resource N, if present (binary, mmap) resource0_wc..N_wc PCI WC map resource N, if prefetchable (binary, mmap) @@ -46,6 +48,7 @@ files, each with their own function. ro - read only file rw - file is readable and writable + wo - write only file mmap - file is mmapable ascii - file contains ascii text binary - file contains binary data @@ -73,6 +76,13 @@ that the device must be enabled for a rom read to return data succesfully. In the event a driver is not bound to the device, it can be enabled using the 'enable' file, documented above. +The 'remove' file is used to remove the PCI device, by writing a non-zero +integer to the file. This does not involve any kind of hot-plug functionality, +e.g. powering off the device. The device is removed from the kernel's list of +PCI devices, the sysfs directory for it is removed, and the device will be +removed from any drivers attached to it. Removal of PCI root buses is +disallowed. + Accessing legacy resources through sysfs ---------------------------------------- -- cgit v1.2.3 From 738a6396c223b486304dda778119dbbca563f019 Mon Sep 17 00:00:00 2001 From: Alex Chiang Date: Fri, 20 Mar 2009 14:56:41 -0600 Subject: PCI: Introduce /sys/bus/pci/devices/.../rescan This interface allows the user to force a rescan of the device's parent bus and all subordinate buses, and rediscover devices removed earlier from this part of the device tree. Cc: Trent Piepho Signed-off-by: Alex Chiang Signed-off-by: Jesse Barnes --- Documentation/ABI/testing/sysfs-bus-pci | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'Documentation') diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci index daa791a9e85..97ad190e13a 100644 --- a/Documentation/ABI/testing/sysfs-bus-pci +++ b/Documentation/ABI/testing/sysfs-bus-pci @@ -74,6 +74,16 @@ Description: hot-remove the PCI device and any of its children. Depends on CONFIG_HOTPLUG. +What: /sys/bus/pci/devices/.../rescan +Date: January 2009 +Contact: Linux PCI developers +Description: + Writing a non-zero value to this attribute will + force a rescan of the device's parent bus and all + child buses, and re-discover devices removed earlier + from this part of the device tree. + Depends on CONFIG_HOTPLUG. + What: /sys/bus/pci/devices/.../vpd Date: February 2008 Contact: Ben Hutchings -- cgit v1.2.3 From f110ca489c9b7cf3f6c9656e383e787f3aee217f Mon Sep 17 00:00:00 2001 From: Alex Chiang Date: Fri, 20 Mar 2009 14:56:56 -0600 Subject: PCI Hotplug: schedule fakephp for feature removal Now that the PCI core is capable of function-level remove and rescan as well as bus-level rescan, there's no functional need to keep fakephp anymore. We keep it around for userspace compatibility reasons, schedule removal in three years. Signed-off-by: Alex Chiang Signed-off-by: Jesse Barnes --- Documentation/feature-removal-schedule.txt | 33 ++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) (limited to 'Documentation') diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 20d3b94703a..8851eea06a0 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -335,6 +335,7 @@ Why: In 2.6.18 the Secmark concept was introduced to replace the "compat_net" Secmark, it is time to deprecate the older mechanism and start the process of removing the old code. Who: Paul Moore + --------------------------- What: sysfs ui for changing p4-clockmod parameters @@ -344,3 +345,35 @@ Why: See commits 129f8ae9b1b5be94517da76009ea956e89104ce8 and Removal is subject to fixing any remaining bugs in ACPI which may cause the thermal throttling not to happen at the right time. Who: Dave Jones , Matthew Garrett + +--------------------------- + +What: fakephp and associated sysfs files in /sys/bus/pci/slots/ +When: 2011 +Why: In 2.6.27, the semantics of /sys/bus/pci/slots was redefined to + represent a machine's physical PCI slots. The change in semantics + had userspace implications, as the hotplug core no longer allowed + drivers to create multiple sysfs files per physical slot (required + for multi-function devices, e.g.). fakephp was seen as a developer's + tool only, and its interface changed. Too late, we learned that + there were some users of the fakephp interface. + + In 2.6.30, the original fakephp interface was restored. At the same + time, the PCI core gained the ability that fakephp provided, namely + function-level hot-remove and hot-add. + + Since the PCI core now provides the same functionality, exposed in: + + /sys/bus/pci/rescan + /sys/bus/pci/devices/.../remove + /sys/bus/pci/devices/.../rescan + + there is no functional reason to maintain fakephp as well. + + We will keep the existing module so that 'modprobe fakephp' will + present the old /sys/bus/pci/slots/... interface for compatibility, + but users are urged to migrate their applications to the API above. + + After a reasonable transition period, we will remove the legacy + fakephp interface. +Who: Alex Chiang -- cgit v1.2.3 From 3a853fb933ddf9c5ea8c9f7c665dd8def26bceae Mon Sep 17 00:00:00 2001 From: Jarkko Nikula Date: Mon, 23 Mar 2009 18:07:47 -0700 Subject: ARM: OMAP: Add command line option for I2C bus speed, v2 This patch adds a new command line option "i2c_bus=bus_id,clkrate" into I2C bus registration helper. Purpose of the option is to override the default board specific bus speed which is supplied by the omap_register_i2c_bus. The default bus speed is typically set to speed of slowest I2C chip on the bus and overriding allow to use some experimental configurations or updated chip versions without any kernel modifications. Cc: linux-i2c@vger.kernel.org Signed-off-by: Jarkko Nikula Signed-off-by: Tony Lindgren --- Documentation/kernel-parameters.txt | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'Documentation') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 54f21a5c262..d775076d156 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -830,6 +830,10 @@ and is between 256 and 4096 characters. It is defined in the file hvc_iucv= [S390] Number of z/VM IUCV hypervisor console (HVC) terminal devices. Valid values: 0..8 + i2c_bus= [HW] Override the default board specific I2C bus speed + Format: + , + i8042.debug [HW] Toggle i8042 debug mode i8042.direct [HW] Put keyboard port into non-translated mode i8042.dumbkbd [HW] Pretend that controller can only read data from -- cgit v1.2.3 From 7954763bb95fd484a76d1151b40956fe331d23b9 Mon Sep 17 00:00:00 2001 From: Jarkko Nikula Date: Mon, 23 Mar 2009 18:07:48 -0700 Subject: ARM: OMAP: Add method to register additional I2C busses on the command line, v2 This patch extends command line option "i2c_bus=bus_id,clkrate" so that it allow to register additional I2C busses that are not registered with omap_register_i2c_bus from board initialization code. Purpose of this is to register additional board busses which are routed to external connectors only without any on board I2C devices. Cc: linux-i2c@vger.kernel.org Signed-off-by: Jarkko Nikula Signed-off-by: Tony Lindgren --- Documentation/kernel-parameters.txt | 2 ++ 1 file changed, 2 insertions(+) (limited to 'Documentation') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index d775076d156..ef9827f7c84 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -831,6 +831,8 @@ and is between 256 and 4096 characters. It is defined in the file terminal devices. Valid values: 0..8 i2c_bus= [HW] Override the default board specific I2C bus speed + or register an additional I2C bus that is not + registered from board initialization code. Format: , -- cgit v1.2.3 From 471c604daf73ff549d374ee54f9e6bfd5a54d4e8 Mon Sep 17 00:00:00 2001 From: Pete Zaitcev Date: Thu, 19 Feb 2009 22:54:45 -0700 Subject: USB: usbmon: Add binary API v1 This patch adds an extension to the binary API so it reaches parity with existing text API (so-called "1u"). The extension delivers additional data, such as ISO descriptors and the interrupt interval. Signed-Off-By: Pete Zaitcev Signed-off-by: Greg Kroah-Hartman --- Documentation/usb/usbmon.txt | 27 ++++++++++++++++++++------- 1 file changed, 20 insertions(+), 7 deletions(-) (limited to 'Documentation') diff --git a/Documentation/usb/usbmon.txt b/Documentation/usb/usbmon.txt index 270481906dc..6c3c625b7f3 100644 --- a/Documentation/usb/usbmon.txt +++ b/Documentation/usb/usbmon.txt @@ -229,16 +229,26 @@ struct usbmon_packet { int status; /* 28: */ unsigned int length; /* 32: Length of data (submitted or actual) */ unsigned int len_cap; /* 36: Delivered length */ - unsigned char setup[8]; /* 40: Only for Control 'S' */ -}; /* 48 bytes total */ + union { /* 40: */ + unsigned char setup[SETUP_LEN]; /* Only for Control S-type */ + struct iso_rec { /* Only for ISO */ + int error_count; + int numdesc; + } iso; + } s; + int interval; /* 48: Only for Interrupt and ISO */ + int start_frame; /* 52: For ISO */ + unsigned int xfer_flags; /* 56: copy of URB's transfer_flags */ + unsigned int ndesc; /* 60: Actual number of ISO descriptors */ +}; /* 64 total length */ These events can be received from a character device by reading with read(2), -with an ioctl(2), or by accessing the buffer with mmap. +with an ioctl(2), or by accessing the buffer with mmap. However, read(2) +only returns first 48 bytes for compatibility reasons. The character device is usually called /dev/usbmonN, where N is the USB bus number. Number zero (/dev/usbmon0) is special and means "all buses". -However, this feature is not implemented yet. Note that specific naming -policy is set by your Linux distribution. +Note that specific naming policy is set by your Linux distribution. If you create /dev/usbmon0 by hand, make sure that it is owned by root and has mode 0600. Otherwise, unpriviledged users will be able to snoop @@ -279,9 +289,10 @@ size is out of [unspecified] bounds for this kernel, the call fails with This call returns the current size of the buffer in bytes. MON_IOCX_GET, defined as _IOW(MON_IOC_MAGIC, 6, struct mon_get_arg) + MON_IOCX_GETX, defined as _IOW(MON_IOC_MAGIC, 10, struct mon_get_arg) -This call waits for events to arrive if none were in the kernel buffer, -then returns the first event. Its argument is a pointer to the following +These calls wait for events to arrive if none were in the kernel buffer, +then return the first event. The argument is a pointer to the following structure: struct mon_get_arg { @@ -294,6 +305,8 @@ Before the call, hdr, data, and alloc should be filled. Upon return, the area pointed by hdr contains the next event structure, and the data buffer contains the data, if any. The event is removed from the kernel buffer. +The MON_IOCX_GET copies 48 bytes, MON_IOCX_GETX copies 64 bytes. + MON_IOCX_MFETCH, defined as _IOWR(MON_IOC_MAGIC, 7, struct mon_mfetch_arg) This ioctl is primarily used when the application accesses the buffer -- cgit v1.2.3 From 8205779114e8f612549d191f8e151526a74ab9f2 Mon Sep 17 00:00:00 2001 From: "Hans J. Koch" Date: Wed, 7 Jan 2009 00:15:39 +0100 Subject: UIO: Add name attributes for mappings and port regions If a UIO device has several memory mappings, it can be difficult for userspace to find the right one. The situation becomes even worse if the UIO driver can handle different versions of a card that have different numbers of mappings. Benedikt Spranger has such cards and pointed this out to me. Thanks, Bene! To address this problem, this patch adds "name" sysfs attributes for each mapping. Userspace can use these to clearly identify each mapping. The name string is optional. If a driver doesn't set it, an empty string will be returned, so this patch won't break existing drivers. The same problem exists for port region information, so a "name" attribute is added there, too. Signed-off-by: Hans J. Koch Signed-off-by: Greg Kroah-Hartman --- Documentation/DocBook/uio-howto.tmpl | 29 +++++++++++++++++++++++++---- 1 file changed, 25 insertions(+), 4 deletions(-) (limited to 'Documentation') diff --git a/Documentation/DocBook/uio-howto.tmpl b/Documentation/DocBook/uio-howto.tmpl index 52e1b79ce0e..8f6e3b2403c 100644 --- a/Documentation/DocBook/uio-howto.tmpl +++ b/Documentation/DocBook/uio-howto.tmpl @@ -41,6 +41,13 @@ GPL version 2. + + 0.8 + 2008-12-24 + hjk + Added name attributes in mem and portio sysfs directories. + + 0.7 2008-12-23 @@ -303,10 +310,17 @@ interested in translating it, please email me appear if the size of the mapping is not 0. - Each mapX/ directory contains two read-only files - that show start address and size of the memory: + Each mapX/ directory contains four read-only files + that show attributes of the memory: + + + name: A string identifier for this mapping. This + is optional, the string can be empty. Drivers can set this to make it + easier for userspace to find the correct mapping. + + addr: The address of memory that can be mapped. @@ -366,10 +380,17 @@ offset = N * getpagesize(); /sys/class/uio/uioX/portio/. - Each portX/ directory contains three read-only - files that show start, size, and type of the port region: + Each portX/ directory contains four read-only + files that show name, start, size, and type of the port region: + + + name: A string identifier for this port region. + The string is optional and can be empty. Drivers can set it to make it + easier for userspace to find a certain port region. + + start: The first port of this region. -- cgit v1.2.3 From e9d376f0fa66bd630fe27403669c6ae6c22a868f Mon Sep 17 00:00:00 2001 From: Jason Baron Date: Thu, 5 Feb 2009 11:51:38 -0500 Subject: dynamic debug: combine dprintk and dynamic printk This patch combines Greg Bank's dprintk() work with the existing dynamic printk patchset, we are now calling it 'dynamic debug'. The new feature of this patchset is a richer /debugfs control file interface, (an example output from my system is at the bottom), which allows fined grained control over the the debug output. The output can be controlled by function, file, module, format string, and line number. for example, enabled all debug messages in module 'nf_conntrack': echo -n 'module nf_conntrack +p' > /mnt/debugfs/dynamic_debug/control to disable them: echo -n 'module nf_conntrack -p' > /mnt/debugfs/dynamic_debug/control A further explanation can be found in the documentation patch. Signed-off-by: Greg Banks Signed-off-by: Jason Baron Signed-off-by: Greg Kroah-Hartman --- Documentation/kernel-parameters.txt | 5 ----- 1 file changed, 5 deletions(-) (limited to 'Documentation') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 54f21a5c262..3a1aa8a4aff 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1816,11 +1816,6 @@ and is between 256 and 4096 characters. It is defined in the file autoconfiguration. Ranges are in pairs (memory base and size). - dynamic_printk Enables pr_debug()/dev_dbg() calls if - CONFIG_DYNAMIC_PRINTK_DEBUG has been enabled. - These can also be switched on/off via - /dynamic_printk/modules - print-fatal-signals= [KNL] debug: print fatal signals print-fatal-signals=1: print segfault info to -- cgit v1.2.3 From 86151fdf38b3795f292b39defbff39d2684b9c8c Mon Sep 17 00:00:00 2001 From: Jason Baron Date: Thu, 5 Feb 2009 11:53:15 -0500 Subject: dynamic debug: update docs updates the documentation for 'dynamic debug' feature. Signed-off-by: Greg Banks Signed-off-by: Jason Baron Signed-off-by: Greg Kroah-Hartman --- Documentation/dynamic-debug-howto.txt | 232 ++++++++++++++++++++++++++++++++++ 1 file changed, 232 insertions(+) create mode 100644 Documentation/dynamic-debug-howto.txt (limited to 'Documentation') diff --git a/Documentation/dynamic-debug-howto.txt b/Documentation/dynamic-debug-howto.txt new file mode 100644 index 00000000000..68394825e86 --- /dev/null +++ b/Documentation/dynamic-debug-howto.txt @@ -0,0 +1,232 @@ + +Introduction +============ + +This document describes how to use the dynamic debug (ddebug) feature. + +Dynamic debug is designed to allow you to dynamically enable/disable kernel +code to obtain additional kernel information. Currently, if +CONFIG_DYNAMIC_DEBUG is set, then all pr_debug()/dev_debug() calls can be +dynamically enabled per-callsite. + +Dynamic debug has even more useful features: + + * Simple query language allows turning on and off debugging statements by + matching any combination of: + + - source filename + - function name + - line number (including ranges of line numbers) + - module name + - format string + + * Provides a debugfs control file: /dynamic_debug/control which can be + read to display the complete list of known debug statements, to help guide you + +Controlling dynamic debug Behaviour +=============================== + +The behaviour of pr_debug()/dev_debug()s are controlled via writing to a +control file in the 'debugfs' filesystem. Thus, you must first mount the debugfs +filesystem, in order to make use of this feature. Subsequently, we refer to the +control file as: /dynamic_debug/control. For example, if you want to +enable printing from source file 'svcsock.c', line 1603 you simply do: + +nullarbor:~ # echo 'file svcsock.c line 1603 +p' > + /dynamic_debug/control + +If you make a mistake with the syntax, the write will fail thus: + +nullarbor:~ # echo 'file svcsock.c wtf 1 +p' > + /dynamic_debug/control +-bash: echo: write error: Invalid argument + +Viewing Dynamic Debug Behaviour +=========================== + +You can view the currently configured behaviour of all the debug statements +via: + +nullarbor:~ # cat /dynamic_debug/control +# filename:lineno [module]function flags format +/usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svc_rdma.c:323 [svcxprt_rdma]svc_rdma_cleanup - "SVCRDMA\040Module\040Removed,\040deregister\040RPC\040RDMA\040transport\012" +/usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svc_rdma.c:341 [svcxprt_rdma]svc_rdma_init - "\011max_inline\040\040\040\040\040\040\040:\040%d\012" +/usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svc_rdma.c:340 [svcxprt_rdma]svc_rdma_init - "\011sq_depth\040\040\040\040\040\040\040\040\040:\040%d\012" +/usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svc_rdma.c:338 [svcxprt_rdma]svc_rdma_init - "\011max_requests\040\040\040\040\040:\040%d\012" +... + + +You can also apply standard Unix text manipulation filters to this +data, e.g. + +nullarbor:~ # grep -i rdma /dynamic_debug/control | wc -l +62 + +nullarbor:~ # grep -i tcp /dynamic_debug/control | wc -l +42 + +Note in particular that the third column shows the enabled behaviour +flags for each debug statement callsite (see below for definitions of the +flags). The default value, no extra behaviour enabled, is "-". So +you can view all the debug statement callsites with any non-default flags: + +nullarbor:~ # awk '$3 != "-"' /dynamic_debug/control +# filename:lineno [module]function flags format +/usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svcsock.c:1603 [sunrpc]svc_send p "svc_process:\040st_sendto\040returned\040%d\012" + + +Command Language Reference +========================== + +At the lexical level, a command comprises a sequence of words separated +by whitespace characters. Note that newlines are treated as word +separators and do *not* end a command or allow multiple commands to +be done together. So these are all equivalent: + +nullarbor:~ # echo -c 'file svcsock.c line 1603 +p' > + /dynamic_debug/control +nullarbor:~ # echo -c ' file svcsock.c line 1603 +p ' > + /dynamic_debug/control +nullarbor:~ # echo -c 'file svcsock.c\nline 1603 +p' > + /dynamic_debug/control +nullarbor:~ # echo -n 'file svcsock.c line 1603 +p' > + /dynamic_debug/control + +Commands are bounded by a write() system call. If you want to do +multiple commands you need to do a separate "echo" for each, like: + +nullarbor:~ # echo 'file svcsock.c line 1603 +p' > /proc/dprintk ;\ +> echo 'file svcsock.c line 1563 +p' > /proc/dprintk + +or even like: + +nullarbor:~ # ( +> echo 'file svcsock.c line 1603 +p' ;\ +> echo 'file svcsock.c line 1563 +p' ;\ +> ) > /proc/dprintk + +At the syntactical level, a command comprises a sequence of match +specifications, followed by a flags change specification. + +command ::= match-spec* flags-spec + +The match-spec's are used to choose a subset of the known dprintk() +callsites to which to apply the flags-spec. Think of them as a query +with implicit ANDs between each pair. Note that an empty list of +match-specs is possible, but is not very useful because it will not +match any debug statement callsites. + +A match specification comprises a keyword, which controls the attribute +of the callsite to be compared, and a value to compare against. Possible +keywords are: + +match-spec ::= 'func' string | + 'file' string | + 'module' string | + 'format' string | + 'line' line-range + +line-range ::= lineno | + '-'lineno | + lineno'-' | + lineno'-'lineno +// Note: line-range cannot contain space, e.g. +// "1-30" is valid range but "1 - 30" is not. + +lineno ::= unsigned-int + +The meanings of each keyword are: + +func + The given string is compared against the function name + of each callsite. Example: + + func svc_tcp_accept + +file + The given string is compared against either the full + pathname or the basename of the source file of each + callsite. Examples: + + file svcsock.c + file /usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svcsock.c + +module + The given string is compared against the module name + of each callsite. The module name is the string as + seen in "lsmod", i.e. without the directory or the .ko + suffix and with '-' changed to '_'. Examples: + + module sunrpc + module nfsd + +format + The given string is searched for in the dynamic debug format + string. Note that the string does not need to match the + entire format, only some part. Whitespace and other + special characters can be escaped using C octal character + escape \ooo notation, e.g. the space character is \040. + Examples: + + format svcrdma: // many of the NFS/RDMA server dprintks + format readahead // some dprintks in the readahead cache + format nfsd:\040SETATTR // how to match a format with whitespace + +line + The given line number or range of line numbers is compared + against the line number of each dprintk() callsite. A single + line number matches the callsite line number exactly. A + range of line numbers matches any callsite between the first + and last line number inclusive. An empty first number means + the first line in the file, an empty line number means the + last number in the file. Examples: + + line 1603 // exactly line 1603 + line 1600-1605 // the six lines from line 1600 to line 1605 + line -1605 // the 1605 lines from line 1 to line 1605 + line 1600- // all lines from line 1600 to the end of the file + +The flags specification comprises a change operation followed +by one or more flag characters. The change operation is one +of the characters: + +- + remove the given flags + ++ + add the given flags + += + set the flags to the given flags + +The flags are: + +p + Causes a printk() message to be emitted to dmesg + +Note the regexp ^[-+=][scp]+$ matches a flags specification. +Note also that there is no convenient syntax to remove all +the flags at once, you need to use "-psc". + +Examples +======== + +// enable the message at line 1603 of file svcsock.c +nullarbor:~ # echo -n 'file svcsock.c line 1603 +p' > + /dynamic_debug/control + +// enable all the messages in file svcsock.c +nullarbor:~ # echo -n 'file svcsock.c +p' > + /dynamic_debug/control + +// enable all the messages in the NFS server module +nullarbor:~ # echo -n 'module nfsd +p' > + /dynamic_debug/control + +// enable all 12 messages in the function svc_process() +nullarbor:~ # echo -n 'func svc_process +p' > + /dynamic_debug/control + +// disable all 12 messages in the function svc_process() +nullarbor:~ # echo -n 'func svc_process -p' > + /dynamic_debug/control -- cgit v1.2.3 From 9898abb3d23311fa227a7f46bf4e40fd2954057f Mon Sep 17 00:00:00 2001 From: Greg Banks Date: Fri, 6 Feb 2009 12:54:26 +1100 Subject: Dynamic debug: allow simple quoting of words Allow simple quoting of words in the dynamic debug control language. This allows more natural specification when using the control language to match against printk formats, e.g #echo -n 'format "Setting node for non-present cpu" +p' > /mnt/debugfs/dynamic_debug/control instead of #echo -n 'format Setting\040node\040for\040non-present\040cpu +p' > /mnt/debugfs/dynamic_debug/control Adjust the dynamic debug documention to describe that and provide a new example. Adjust the existing examples in the documentation to reflect the current whitespace escaping behaviour when reading the control file. Fix some minor documentation trailing whitespace. Signed-off-by: Greg Banks Acked-by: Jason Baron Signed-off-by: Greg Kroah-Hartman --- Documentation/dynamic-debug-howto.txt | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) (limited to 'Documentation') diff --git a/Documentation/dynamic-debug-howto.txt b/Documentation/dynamic-debug-howto.txt index 68394825e86..674c5663d34 100644 --- a/Documentation/dynamic-debug-howto.txt +++ b/Documentation/dynamic-debug-howto.txt @@ -49,10 +49,10 @@ via: nullarbor:~ # cat /dynamic_debug/control # filename:lineno [module]function flags format -/usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svc_rdma.c:323 [svcxprt_rdma]svc_rdma_cleanup - "SVCRDMA\040Module\040Removed,\040deregister\040RPC\040RDMA\040transport\012" -/usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svc_rdma.c:341 [svcxprt_rdma]svc_rdma_init - "\011max_inline\040\040\040\040\040\040\040:\040%d\012" -/usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svc_rdma.c:340 [svcxprt_rdma]svc_rdma_init - "\011sq_depth\040\040\040\040\040\040\040\040\040:\040%d\012" -/usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svc_rdma.c:338 [svcxprt_rdma]svc_rdma_init - "\011max_requests\040\040\040\040\040:\040%d\012" +/usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svc_rdma.c:323 [svcxprt_rdma]svc_rdma_cleanup - "SVCRDMA Module Removed, deregister RPC RDMA transport\012" +/usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svc_rdma.c:341 [svcxprt_rdma]svc_rdma_init - "\011max_inline : %d\012" +/usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svc_rdma.c:340 [svcxprt_rdma]svc_rdma_init - "\011sq_depth : %d\012" +/usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svc_rdma.c:338 [svcxprt_rdma]svc_rdma_init - "\011max_requests : %d\012" ... @@ -72,7 +72,7 @@ you can view all the debug statement callsites with any non-default flags: nullarbor:~ # awk '$3 != "-"' /dynamic_debug/control # filename:lineno [module]function flags format -/usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svcsock.c:1603 [sunrpc]svc_send p "svc_process:\040st_sendto\040returned\040%d\012" +/usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svcsock.c:1603 [sunrpc]svc_send p "svc_process: st_sendto returned %d\012" Command Language Reference @@ -166,11 +166,15 @@ format entire format, only some part. Whitespace and other special characters can be escaped using C octal character escape \ooo notation, e.g. the space character is \040. + Alternatively, the string can be enclosed in double quote + characters (") or single quote characters ('). Examples: format svcrdma: // many of the NFS/RDMA server dprintks format readahead // some dprintks in the readahead cache - format nfsd:\040SETATTR // how to match a format with whitespace + format nfsd:\040SETATTR // one way to match a format with whitespace + format "nfsd: SETATTR" // a neater way to match a format with whitespace + format 'nfsd: SETATTR' // yet another way to match a format with whitespace line The given line number or range of line numbers is compared @@ -230,3 +234,7 @@ nullarbor:~ # echo -n 'func svc_process +p' > // disable all 12 messages in the function svc_process() nullarbor:~ # echo -n 'func svc_process -p' > /dynamic_debug/control + +// enable messages for NFS calls READ, READLINK, READDIR and READDIR+. +nullarbor:~ # echo -n 'format "nfsd: READ" +p' > + /dynamic_debug/control -- cgit v1.2.3 From 07e86f405addc6436eb969b8279bb14a6dcacce4 Mon Sep 17 00:00:00 2001 From: Avishay Traeger Date: Tue, 24 Mar 2009 12:40:18 +0100 Subject: block: Repeated lines in switching-sched.txt These lines appear in this file twice - removed one occurrence. Signed-off-by: Avishay Traeger Signed-off-by: Jens Axboe --- Documentation/block/switching-sched.txt | 6 ------ 1 file changed, 6 deletions(-) (limited to 'Documentation') diff --git a/Documentation/block/switching-sched.txt b/Documentation/block/switching-sched.txt index 634c952e196..d5af3f63081 100644 --- a/Documentation/block/switching-sched.txt +++ b/Documentation/block/switching-sched.txt @@ -35,9 +35,3 @@ noop anticipatory deadline [cfq] # echo anticipatory > /sys/block/hda/queue/scheduler # cat /sys/block/hda/queue/scheduler noop [anticipatory] deadline cfq - -Each io queue has a set of io scheduler tunables associated with it. These -tunables control how the io scheduler works. You can find these entries -in: - -/sys/block//queue/iosched -- cgit v1.2.3 From 431429ff788598a19c1a193b9fca3961b7f55916 Mon Sep 17 00:00:00 2001 From: Hendrik Brueckner Date: Thu, 26 Mar 2009 15:23:55 +0100 Subject: [S390] hvc_iucv: Provide IUCV z/VM user ID filtering This patch introduces the kernel parameter hvc_iucv_allow= that specifies a comma-separated list of z/VM user IDs. If specified, the z/VM IUCV hypervisor console device driver accepts IUCV connections from listed z/VM user IDs only. Signed-off-by: Hendrik Brueckner Signed-off-by: Martin Schwidefsky --- Documentation/kernel-parameters.txt | 3 +++ 1 file changed, 3 insertions(+) (limited to 'Documentation') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 54f21a5c262..9f932a76a94 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -829,6 +829,9 @@ and is between 256 and 4096 characters. It is defined in the file hvc_iucv= [S390] Number of z/VM IUCV hypervisor console (HVC) terminal devices. Valid values: 0..8 + hvc_iucv_allow= [S390] Comma-separated list of z/VM user IDs. + If specified, z/VM IUCV HVC accepts connections + from listed z/VM user IDs only. i8042.debug [HW] Toggle i8042 debug mode i8042.direct [HW] Put keyboard port into non-translated mode -- cgit v1.2.3 From 7676b8fd701beb47cc1b4cc291acaa07287ea69a Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Thu, 26 Mar 2009 20:47:00 +0000 Subject: dontdiff: Fix asm exclude Now that the headers are in arch/foo/include/asm we don't want to exclude them when preparing diff files. Closes-bug: 12921 Signed-off-by: Alan Cox Signed-off-by: Linus Torvalds --- Documentation/dontdiff | 1 - 1 file changed, 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/dontdiff b/Documentation/dontdiff index 1e89a51ea49..88519daab6e 100644 --- a/Documentation/dontdiff +++ b/Documentation/dontdiff @@ -62,7 +62,6 @@ aic7*reg_print.c* aic7*seq.h* aicasm aicdb.h* -asm asm-offsets.h asm_offsets.h autoconf.h* -- cgit v1.2.3 From df4b6806d35ca6adedd5c0a7e36ac74af1c32d7a Mon Sep 17 00:00:00 2001 From: Timur Tabi Date: Wed, 11 Mar 2009 19:22:04 -0500 Subject: powerpc: clean up ssi.txt, add definition for fsl,ssi-asynchronous Add the definition of the fsl,ssi-asynchronous property to ssi.txt (documentation of the device tree bindings for the Freescale SSI device). Also tidy up the layout of ssi.txt. Signed-off-by: Timur Tabi Signed-off-by: Kumar Gala --- Documentation/powerpc/dts-bindings/fsl/ssi.txt | 68 +++++++++++++++----------- 1 file changed, 39 insertions(+), 29 deletions(-) (limited to 'Documentation') diff --git a/Documentation/powerpc/dts-bindings/fsl/ssi.txt b/Documentation/powerpc/dts-bindings/fsl/ssi.txt index 73133228893..5ff76c9c57d 100644 --- a/Documentation/powerpc/dts-bindings/fsl/ssi.txt +++ b/Documentation/powerpc/dts-bindings/fsl/ssi.txt @@ -4,46 +4,56 @@ The SSI is a serial device that communicates with audio codecs. It can be programmed in AC97, I2S, left-justified, or right-justified modes. Required properties: -- compatible : compatible list, containing "fsl,ssi" -- cell-index : the SSI, <0> = SSI1, <1> = SSI2, and so on -- reg : offset and length of the register set for the device -- interrupts : where a is the interrupt number and b is a - field that represents an encoding of the sense and - level information for the interrupt. This should be - encoded based on the information in section 2) - depending on the type of interrupt controller you - have. -- interrupt-parent : the phandle for the interrupt controller that - services interrupts for this device. -- fsl,mode : the operating mode for the SSI interface - "i2s-slave" - I2S mode, SSI is clock slave - "i2s-master" - I2S mode, SSI is clock master - "lj-slave" - left-justified mode, SSI is clock slave - "lj-master" - l.j. mode, SSI is clock master - "rj-slave" - right-justified mode, SSI is clock slave - "rj-master" - r.j., SSI is clock master - "ac97-slave" - AC97 mode, SSI is clock slave - "ac97-master" - AC97 mode, SSI is clock master -- fsl,playback-dma: phandle to a node for the DMA channel to use for +- compatible: Compatible list, contains "fsl,ssi". +- cell-index: The SSI, <0> = SSI1, <1> = SSI2, and so on. +- reg: Offset and length of the register set for the device. +- interrupts: where a is the interrupt number and b is a + field that represents an encoding of the sense and + level information for the interrupt. This should be + encoded based on the information in section 2) + depending on the type of interrupt controller you + have. +- interrupt-parent: The phandle for the interrupt controller that + services interrupts for this device. +- fsl,mode: The operating mode for the SSI interface. + "i2s-slave" - I2S mode, SSI is clock slave + "i2s-master" - I2S mode, SSI is clock master + "lj-slave" - left-justified mode, SSI is clock slave + "lj-master" - l.j. mode, SSI is clock master + "rj-slave" - right-justified mode, SSI is clock slave + "rj-master" - r.j., SSI is clock master + "ac97-slave" - AC97 mode, SSI is clock slave + "ac97-master" - AC97 mode, SSI is clock master +- fsl,playback-dma: Phandle to a node for the DMA channel to use for playback of audio. This is typically dictated by SOC design. See the notes below. -- fsl,capture-dma: phandle to a node for the DMA channel to use for +- fsl,capture-dma: Phandle to a node for the DMA channel to use for capture (recording) of audio. This is typically dictated by SOC design. See the notes below. -- fsl,fifo-depth: the number of elements in the transmit and receive FIFOs. +- fsl,fifo-depth: The number of elements in the transmit and receive FIFOs. This number is the maximum allowed value for SFCSR[TFWM0]. +- fsl,ssi-asynchronous: + If specified, the SSI is to be programmed in asynchronous + mode. In this mode, pins SRCK, STCK, SRFS, and STFS must + all be connected to valid signals. In synchronous mode, + SRCK and SRFS are ignored. Asynchronous mode allows + playback and capture to use different sample sizes and + sample rates. Some drivers may require that SRCK and STCK + be connected together, and SRFS and STFS be connected + together. This would still allow different sample sizes, + but not different sample rates. Optional properties: -- codec-handle : phandle to a 'codec' node that defines an audio - codec connected to this SSI. This node is typically - a child of an I2C or other control node. +- codec-handle: Phandle to a 'codec' node that defines an audio + codec connected to this SSI. This node is typically + a child of an I2C or other control node. Child 'codec' node required properties: -- compatible : compatible list, contains the name of the codec +- compatible: Compatible list, contains the name of the codec Child 'codec' node optional properties: -- clock-frequency : The frequency of the input clock, which typically - comes from an on-board dedicated oscillator. +- clock-frequency: The frequency of the input clock, which typically comes + from an on-board dedicated oscillator. Notes on fsl,playback-dma and fsl,capture-dma: -- cgit v1.2.3 From 6ee7d33056f6e6fc7437d980dcc741816deedd0f Mon Sep 17 00:00:00 2001 From: "Luis R. Rodriguez" Date: Fri, 20 Mar 2009 23:53:06 -0400 Subject: cfg80211: make regdom module parameter available oustide of OLD_REG It seems a few users are using this module parameter although its not recommended. People are finding it useful despite there being utilities for setting this in userspace. I'm not aware of any distribution using this though. Until userspace and distributions catch up with a default userspace automatic replacement (GeoClue integration would be nirvana) we copy the ieee80211_regdom module parameter from OLD_REG to the new reg code to help these users migrate. Users who are using the non-valid ISO / IEC 3166 alpha "EU" in their ieee80211_regdom module parameter and migrate to non-OLD_REG enabled system will world roam. This also schedules removal of this same ieee80211_regdom module parameter circa March 2010. Hope is by then nirvana is reached and users will abandoned the module parameter completely. Signed-off-by: Luis R. Rodriguez Signed-off-by: John W. Linville --- Documentation/feature-removal-schedule.txt | 30 ++++++++++++++++++++++++++---- 1 file changed, 26 insertions(+), 4 deletions(-) (limited to 'Documentation') diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index e47c0ff8ba7..8365f52a354 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -6,7 +6,31 @@ be removed from this file. --------------------------- -What: old static regulatory information and ieee80211_regdom module parameter +What: The ieee80211_regdom module parameter +When: March 2010 + +Why: This was inherited by the CONFIG_WIRELESS_OLD_REGULATORY code, + and currently serves as an option for users to define an + ISO / IEC 3166 alpha2 code for the country they are currently + present in. Although there are userspace API replacements for this + through nl80211 distributions haven't yet caught up with implementing + decent alternatives through standard GUIs. Although available as an + option through iw or wpa_supplicant its just a matter of time before + distributions pick up good GUI options for this. The ideal solution + would actually consist of intelligent designs which would do this for + the user automatically even when travelling through different countries. + Until then we leave this module parameter as a compromise. + + When userspace improves with reasonable widely-available alternatives for + this we will no longer need this module parameter. This entry hopes that + by the super-futuristically looking date of "March 2010" we will have + such replacements widely available. + +Who: Luis R. Rodriguez + +--------------------------- + +What: old static regulatory information When: 2.6.29 Why: The old regulatory infrastructure has been replaced with a new one which does not require statically defined regulatory domains. We do @@ -17,9 +41,7 @@ Why: The old regulatory infrastructure has been replaced with a new one * JP * EU and used by default the US when CONFIG_WIRELESS_OLD_REGULATORY was - set. We also kept around the ieee80211_regdom module parameter in case - some applications were relying on it. Changing regulatory domains - can now be done instead by using nl80211, as is done with iw. + set. Who: Luis R. Rodriguez --------------------------- -- cgit v1.2.3 From 04de83815993714a7ba2618f637fa1092a5f664b Mon Sep 17 00:00:00 2001 From: Kalle Valo Date: Sun, 22 Mar 2009 21:57:35 +0200 Subject: mac80211: add beacon filtering support Add IEEE80211_HW_BEACON_FILTERING flag so that driver inform that it supports beacon filtering. Drivers need to call the new function ieee80211_beacon_loss() to notify about beacon loss. Signed-off-by: Kalle Valo Signed-off-by: John W. Linville --- Documentation/DocBook/mac80211.tmpl | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'Documentation') diff --git a/Documentation/DocBook/mac80211.tmpl b/Documentation/DocBook/mac80211.tmpl index 8af6d962687..fbeaffc1dcc 100644 --- a/Documentation/DocBook/mac80211.tmpl +++ b/Documentation/DocBook/mac80211.tmpl @@ -227,6 +227,12 @@ usage should require reading the full document. !Pinclude/net/mac80211.h Powersave support + + Beacon filter support +!Pinclude/net/mac80211.h Beacon filter support +!Finclude/net/mac80211.h ieee80211_beacon_loss + + Multiple queues and QoS support TBD -- cgit v1.2.3 From 8a5117d80fe93de5df5b56480054f7df1fd20755 Mon Sep 17 00:00:00 2001 From: "Luis R. Rodriguez" Date: Tue, 24 Mar 2009 21:21:07 -0400 Subject: cfg80211: default CONFIG_WIRELESS_OLD_REGULATORY to n And update description and feature-removal schedule according to the new plan. Signed-off-by: Luis R. Rodriguez Signed-off-by: John W. Linville --- Documentation/feature-removal-schedule.txt | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) (limited to 'Documentation') diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 8365f52a354..02ea3773535 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -7,7 +7,7 @@ be removed from this file. --------------------------- What: The ieee80211_regdom module parameter -When: March 2010 +When: March 2010 / desktop catchup Why: This was inherited by the CONFIG_WIRELESS_OLD_REGULATORY code, and currently serves as an option for users to define an @@ -30,18 +30,23 @@ Who: Luis R. Rodriguez --------------------------- -What: old static regulatory information -When: 2.6.29 +What: CONFIG_WIRELESS_OLD_REGULATORY - old static regulatory information +When: March 2010 / desktop catchup + Why: The old regulatory infrastructure has been replaced with a new one which does not require statically defined regulatory domains. We do not want to keep static regulatory domains in the kernel due to the the dynamic nature of regulatory law and localization. We kept around the old static definitions for the regulatory domains of: + * US * JP * EU + and used by default the US when CONFIG_WIRELESS_OLD_REGULATORY was - set. + set. We will remove this option once the standard Linux desktop catches + up with the new userspace APIs we have implemented. + Who: Luis R. Rodriguez --------------------------- -- cgit v1.2.3 From 58bfbb51ff2b0fdc6c732ff3d72f50aa632b67a2 Mon Sep 17 00:00:00 2001 From: Paul Moore Date: Fri, 27 Mar 2009 17:10:41 -0400 Subject: selinux: Remove the "compat_net" compatibility code The SELinux "compat_net" is marked as deprecated, the time has come to finally remove it from the kernel. Further code simplifications are likely in the future, but this patch was intended to be a simple, straight-up removal of the compat_net code. Signed-off-by: Paul Moore Signed-off-by: James Morris --- Documentation/feature-removal-schedule.txt | 11 ----------- Documentation/kernel-parameters.txt | 9 --------- 2 files changed, 20 deletions(-) (limited to 'Documentation') diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 02ea3773535..049a96247f5 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -355,17 +355,6 @@ Who: Hans de Goede --------------------------- -What: SELinux "compat_net" functionality -When: 2.6.30 at the earliest -Why: In 2.6.18 the Secmark concept was introduced to replace the "compat_net" - network access control functionality of SELinux. Secmark offers both - better performance and greater flexibility than the "compat_net" - mechanism. Now that the major Linux distributions have moved to - Secmark, it is time to deprecate the older mechanism and start the - process of removing the old code. -Who: Paul Moore ---------------------------- - What: sysfs ui for changing p4-clockmod parameters When: September 2009 Why: See commits 129f8ae9b1b5be94517da76009ea956e89104ce8 and diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index fa4e1239a8f..d1b082772e3 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -2019,15 +2019,6 @@ and is between 256 and 4096 characters. It is defined in the file If enabled at boot time, /selinux/disable can be used later to disable prior to initial policy load. - selinux_compat_net = - [SELINUX] Set initial selinux_compat_net flag value. - Format: { "0" | "1" } - 0 -- use new secmark-based packet controls - 1 -- use legacy packet controls - Default value is 0 (preferred). - Value can be changed at runtime via - /selinux/compat_net. - serialnumber [BUGS=X86-32] shapers= [NET] -- cgit v1.2.3 From 4303154e86597885bc3cbc178a48ccbc8213875f Mon Sep 17 00:00:00 2001 From: Etienne Basset Date: Fri, 27 Mar 2009 17:11:01 -0400 Subject: smack: Add a new '-CIPSO' option to the network address label configuration This patch adds a new special option '-CIPSO' to the Smack subsystem. When used in the netlabel list, it means "use CIPSO networking". A use case is when your local network speaks CIPSO and you want also to connect to the unlabeled Internet. This patch also add some documentation describing that. The patch also corrects an oops when setting a '' SMACK64 xattr to a file. Signed-off-by: Etienne Basset Signed-off-by: Paul Moore Acked-by: Casey Schaufler Signed-off-by: James Morris --- Documentation/Smack.txt | 42 +++++++++++++++++++++++++++++++++++++----- 1 file changed, 37 insertions(+), 5 deletions(-) (limited to 'Documentation') diff --git a/Documentation/Smack.txt b/Documentation/Smack.txt index 989c2fcd811..629c92e9978 100644 --- a/Documentation/Smack.txt +++ b/Documentation/Smack.txt @@ -184,14 +184,16 @@ length. Single character labels using special characters, that being anything other than a letter or digit, are reserved for use by the Smack development team. Smack labels are unstructured, case sensitive, and the only operation ever performed on them is comparison for equality. Smack labels cannot -contain unprintable characters or the "/" (slash) character. +contain unprintable characters or the "/" (slash) character. Smack labels +cannot begin with a '-', which is reserved for special options. There are some predefined labels: - _ Pronounced "floor", a single underscore character. - ^ Pronounced "hat", a single circumflex character. - * Pronounced "star", a single asterisk character. - ? Pronounced "huh", a single question mark character. + _ Pronounced "floor", a single underscore character. + ^ Pronounced "hat", a single circumflex character. + * Pronounced "star", a single asterisk character. + ? Pronounced "huh", a single question mark character. + @ Pronounced "Internet", a single at sign character. Every task on a Smack system is assigned a label. System tasks, such as init(8) and systems daemons, are run with the floor ("_") label. User tasks @@ -412,6 +414,36 @@ sockets. A privileged program may set this to match the label of another task with which it hopes to communicate. +Smack Netlabel Exceptions + +You will often find that your labeled application has to talk to the outside, +unlabeled world. To do this there's a special file /smack/netlabel where you can +add some exceptions in the form of : +@IP1 LABEL1 or +@IP2/MASK LABEL2 + +It means that your application will have unlabeled access to @IP1 if it has +write access on LABEL1, and access to the subnet @IP2/MASK if it has write +access on LABEL2. + +Entries in the /smack/netlabel file are matched by longest mask first, like in +classless IPv4 routing. + +A special label '@' and an option '-CIPSO' can be used there : +@ means Internet, any application with any label has access to it +-CIPSO means standard CIPSO networking + +If you don't know what CIPSO is and don't plan to use it, you can just do : +echo 127.0.0.1 -CIPSO > /smack/netlabel +echo 0.0.0.0/0 @ > /smack/netlabel + +If you use CIPSO on your 192.168.0.0/16 local network and need also unlabeled +Internet access, you can have : +echo 127.0.0.1 -CIPSO > /smack/netlabel +echo 192.168.0.0/16 -CIPSO > /smack/netlabel +echo 0.0.0.0/0 @ > /smack/netlabel + + Writing Applications for Smack There are three sorts of applications that will run on a Smack system. How an -- cgit v1.2.3 From 06705bff9114531a997a7d0c2520bea0f2927410 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Sat, 28 Mar 2009 10:59:57 -0400 Subject: ext4: Regularize mount options Add support for using the mount options "barrier" and "nobarrier", and "auto_da_alloc" and "noauto_da_alloc", which is more consistent than "barrier=<0|1>" or "auto_da_alloc=<0|1>". Most other ext3/ext4 mount options use the foo/nofoo naming convention. We allow the old forms of these mount options for backwards compatibility. Signed-off-by: "Theodore Ts'o" --- Documentation/filesystems/ext4.txt | 25 +++++++++++++++++++++++-- 1 file changed, 23 insertions(+), 2 deletions(-) (limited to 'Documentation') diff --git a/Documentation/filesystems/ext4.txt b/Documentation/filesystems/ext4.txt index 5c484aec2ba..97882df0486 100644 --- a/Documentation/filesystems/ext4.txt +++ b/Documentation/filesystems/ext4.txt @@ -183,8 +183,8 @@ commit=nrsec (*) Ext4 can be told to sync all its data and metadata performance. barrier=<0|1(*)> This enables/disables the use of write barriers in - the jbd code. barrier=0 disables, barrier=1 enables. - This also requires an IO stack which can support +barrier(*) the jbd code. barrier=0 disables, barrier=1 enables. +nobarrier This also requires an IO stack which can support barriers, and if jbd gets an error on a barrier write, it will disable again with a warning. Write barriers enforce proper on-disk ordering @@ -192,6 +192,9 @@ barrier=<0|1(*)> This enables/disables the use of write barriers in safe to use, at some performance penalty. If your disks are battery-backed in one way or another, disabling barriers may safely improve performance. + The mount options "barrier" and "nobarrier" can + also be used to enable or disable barriers, for + consistency with other ext4 mount options. inode_readahead=n This tuning parameter controls the maximum number of inode table blocks that ext4's inode @@ -313,6 +316,24 @@ journal_ioprio=prio The I/O priority (from 0 to 7, where 0 is the a slightly higher priority than the default I/O priority. +auto_da_alloc(*) Many broken applications don't use fsync() when +noauto_da_alloc replacing existing files via patterns such as + fd = open("foo.new")/write(fd,..)/close(fd)/ + rename("foo.new", "foo"), or worse yet, + fd = open("foo", O_TRUNC)/write(fd,..)/close(fd). + If auto_da_alloc is enabled, ext4 will detect + the replace-via-rename and replace-via-truncate + patterns and force that any delayed allocation + blocks are allocated such that at the next + journal commit, in the default data=ordered + mode, the data blocks of the new file are forced + to disk before the rename() operation is + commited. This provides roughly the same level + of guarantees as ext3, and avoids the + "zero-length" problem that can happen when a + system crashes before the delayed allocation + blocks are forced to disk. + Data Mode ========= There are 3 different data modes: -- cgit v1.2.3 From 764c16918fb2347b3cbc8f6030b2b6561911bc32 Mon Sep 17 00:00:00 2001 From: Jean Delvare Date: Sat, 28 Mar 2009 21:34:40 +0100 Subject: i2c: Document the different ways to instantiate i2c devices On popular demand, here comes some documentation about how to instantiate i2c devices in the new (standard) i2c device driver binding model. I have also clarified how the class bitfield lets driver authors control which buses are probed in the auto-detect case, and warned more loudly against the abuse of this method. Signed-off-by: Jean Delvare Acked-by: Michael Lawnick Acked-by: Hans Verkuil --- Documentation/i2c/instantiating-devices | 167 ++++++++++++++++++++++++++++++++ Documentation/i2c/writing-clients | 19 +++- 2 files changed, 182 insertions(+), 4 deletions(-) create mode 100644 Documentation/i2c/instantiating-devices (limited to 'Documentation') diff --git a/Documentation/i2c/instantiating-devices b/Documentation/i2c/instantiating-devices new file mode 100644 index 00000000000..b55ce57a84d --- /dev/null +++ b/Documentation/i2c/instantiating-devices @@ -0,0 +1,167 @@ +How to instantiate I2C devices +============================== + +Unlike PCI or USB devices, I2C devices are not enumerated at the hardware +level. Instead, the software must know which devices are connected on each +I2C bus segment, and what address these devices are using. For this +reason, the kernel code must instantiate I2C devices explicitly. There are +several ways to achieve this, depending on the context and requirements. + + +Method 1: Declare the I2C devices by bus number +----------------------------------------------- + +This method is appropriate when the I2C bus is a system bus as is the case +for many embedded systems. On such systems, each I2C bus has a number +which is known in advance. It is thus possible to pre-declare the I2C +devices which live on this bus. This is done with an array of struct +i2c_board_info which is registered by calling i2c_register_board_info(). + +Example (from omap2 h4): + +static struct i2c_board_info __initdata h4_i2c_board_info[] = { + { + I2C_BOARD_INFO("isp1301_omap", 0x2d), + .irq = OMAP_GPIO_IRQ(125), + }, + { /* EEPROM on mainboard */ + I2C_BOARD_INFO("24c01", 0x52), + .platform_data = &m24c01, + }, + { /* EEPROM on cpu card */ + I2C_BOARD_INFO("24c01", 0x57), + .platform_data = &m24c01, + }, +}; + +static void __init omap_h4_init(void) +{ + (...) + i2c_register_board_info(1, h4_i2c_board_info, + ARRAY_SIZE(h4_i2c_board_info)); + (...) +} + +The above code declares 3 devices on I2C bus 1, including their respective +addresses and custom data needed by their drivers. When the I2C bus in +question is registered, the I2C devices will be instantiated automatically +by i2c-core. + +The devices will be automatically unbound and destroyed when the I2C bus +they sit on goes away (if ever.) + + +Method 2: Instantiate the devices explicitly +-------------------------------------------- + +This method is appropriate when a larger device uses an I2C bus for +internal communication. A typical case is TV adapters. These can have a +tuner, a video decoder, an audio decoder, etc. usually connected to the +main chip by the means of an I2C bus. You won't know the number of the I2C +bus in advance, so the method 1 described above can't be used. Instead, +you can instantiate your I2C devices explicitly. This is done by filling +a struct i2c_board_info and calling i2c_new_device(). + +Example (from the sfe4001 network driver): + +static struct i2c_board_info sfe4001_hwmon_info = { + I2C_BOARD_INFO("max6647", 0x4e), +}; + +int sfe4001_init(struct efx_nic *efx) +{ + (...) + efx->board_info.hwmon_client = + i2c_new_device(&efx->i2c_adap, &sfe4001_hwmon_info); + + (...) +} + +The above code instantiates 1 I2C device on the I2C bus which is on the +network adapter in question. + +A variant of this is when you don't know for sure if an I2C device is +present or not (for example for an optional feature which is not present +on cheap variants of a board but you have no way to tell them apart), or +it may have different addresses from one board to the next (manufacturer +changing its design without notice). In this case, you can call +i2c_new_probed_device() instead of i2c_new_device(). + +Example (from the pnx4008 OHCI driver): + +static const unsigned short normal_i2c[] = { 0x2c, 0x2d, I2C_CLIENT_END }; + +static int __devinit usb_hcd_pnx4008_probe(struct platform_device *pdev) +{ + (...) + struct i2c_adapter *i2c_adap; + struct i2c_board_info i2c_info; + + (...) + i2c_adap = i2c_get_adapter(2); + memset(&i2c_info, 0, sizeof(struct i2c_board_info)); + strlcpy(i2c_info.name, "isp1301_pnx", I2C_NAME_SIZE); + isp1301_i2c_client = i2c_new_probed_device(i2c_adap, &i2c_info, + normal_i2c); + i2c_put_adapter(i2c_adap); + (...) +} + +The above code instantiates up to 1 I2C device on the I2C bus which is on +the OHCI adapter in question. It first tries at address 0x2c, if nothing +is found there it tries address 0x2d, and if still nothing is found, it +simply gives up. + +The driver which instantiated the I2C device is responsible for destroying +it on cleanup. This is done by calling i2c_unregister_device() on the +pointer that was earlier returned by i2c_new_device() or +i2c_new_probed_device(). + + +Method 3: Probe an I2C bus for certain devices +---------------------------------------------- + +Sometimes you do not have enough information about an I2C device, not even +to call i2c_new_probed_device(). The typical case is hardware monitoring +chips on PC mainboards. There are several dozen models, which can live +at 25 different addresses. Given the huge number of mainboards out there, +it is next to impossible to build an exhaustive list of the hardware +monitoring chips being used. Fortunately, most of these chips have +manufacturer and device ID registers, so they can be identified by +probing. + +In that case, I2C devices are neither declared nor instantiated +explicitly. Instead, i2c-core will probe for such devices as soon as their +drivers are loaded, and if any is found, an I2C device will be +instantiated automatically. In order to prevent any misbehavior of this +mechanism, the following restrictions apply: +* The I2C device driver must implement the detect() method, which + identifies a supported device by reading from arbitrary registers. +* Only buses which are likely to have a supported device and agree to be + probed, will be probed. For example this avoids probing for hardware + monitoring chips on a TV adapter. + +Example: +See lm90_driver and lm90_detect() in drivers/hwmon/lm90.c + +I2C devices instantiated as a result of such a successful probe will be +destroyed automatically when the driver which detected them is removed, +or when the underlying I2C bus is itself destroyed, whichever happens +first. + +Those of you familiar with the i2c subsystem of 2.4 kernels and early 2.6 +kernels will find out that this method 3 is essentially similar to what +was done there. Two significant differences are: +* Probing is only one way to instantiate I2C devices now, while it was the + only way back then. Where possible, methods 1 and 2 should be preferred. + Method 3 should only be used when there is no other way, as it can have + undesirable side effects. +* I2C buses must now explicitly say which I2C driver classes can probe + them (by the means of the class bitfield), while all I2C buses were + probed by default back then. The default is an empty class which means + that no probing happens. The purpose of the class bitfield is to limit + the aforementioned undesirable side effects. + +Once again, method 3 should be avoided wherever possible. Explicit device +instantiation (methods 1 and 2) is much preferred for it is safer and +faster. diff --git a/Documentation/i2c/writing-clients b/Documentation/i2c/writing-clients index 6b9af7d479c..c1a06f989cf 100644 --- a/Documentation/i2c/writing-clients +++ b/Documentation/i2c/writing-clients @@ -207,15 +207,26 @@ You simply have to define a detect callback which will attempt to identify supported devices (returning 0 for supported ones and -ENODEV for unsupported ones), a list of addresses to probe, and a device type (or class) so that only I2C buses which may have that type of device -connected (and not otherwise enumerated) will be probed. The i2c -core will then call you back as needed and will instantiate a device -for you for every successful detection. +connected (and not otherwise enumerated) will be probed. For example, +a driver for a hardware monitoring chip for which auto-detection is +needed would set its class to I2C_CLASS_HWMON, and only I2C adapters +with a class including I2C_CLASS_HWMON would be probed by this driver. +Note that the absence of matching classes does not prevent the use of +a device of that type on the given I2C adapter. All it prevents is +auto-detection; explicit instantiation of devices is still possible. Note that this mechanism is purely optional and not suitable for all devices. You need some reliable way to identify the supported devices (typically using device-specific, dedicated identification registers), otherwise misdetections are likely to occur and things can get wrong -quickly. +quickly. Keep in mind that the I2C protocol doesn't include any +standard way to detect the presence of a chip at a given address, let +alone a standard way to identify devices. Even worse is the lack of +semantics associated to bus transfers, which means that the same +transfer can be seen as a read operation by a chip and as a write +operation by another chip. For these reasons, explicit device +instantiation should always be preferred to auto-detection where +possible. Device Deletion -- cgit v1.2.3 From f02e3d74e9f89e3d49284e7c99217993b657f5b7 Mon Sep 17 00:00:00 2001 From: Jean Delvare Date: Sat, 28 Mar 2009 21:34:40 +0100 Subject: i2c: Let checkpatch shout on users of the legacy model As suggested by Mauro Carvalho Chehab. Signed-off-by: Jean Delvare Cc: Mauro Carvalho Chehab --- Documentation/feature-removal-schedule.txt | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 02ea3773535..7907586c6e0 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -340,7 +340,8 @@ Who: Krzysztof Piotr Oledzki --------------------------- What: i2c_attach_client(), i2c_detach_client(), i2c_driver->detach_client() -When: 2.6.29 (ideally) or 2.6.30 (more likely) +When: 2.6.30 +Check: i2c_attach_client i2c_detach_client Why: Deprecated by the new (standard) device driver binding model. Use i2c_driver->probe() and ->remove() instead. Who: Jean Delvare -- cgit v1.2.3 From d2dd14ac1847082d4bb955619e86ed315c0ecd20 Mon Sep 17 00:00:00 2001 From: Jean Delvare Date: Sat, 28 Mar 2009 21:34:41 +0100 Subject: i2c-nforce2: Add support for MCP67, MCP73, MCP78S and MCP79 The MCP78S and MCP79 appear to be compatible with the previous nForce chips as far as the SMBus controller is concerned. The MCP67 and MCP73 were not tested yet but I'd be very surprised if they weren't compatible too. Signed-off-by: Jean Delvare Cc: Oleg Ryjkov Cc: Malcolm Lalkaka Cc: Zbigniew Luszpinski --- Documentation/i2c/busses/i2c-nforce2 | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) (limited to 'Documentation') diff --git a/Documentation/i2c/busses/i2c-nforce2 b/Documentation/i2c/busses/i2c-nforce2 index fae3495bcba..9698c396b83 100644 --- a/Documentation/i2c/busses/i2c-nforce2 +++ b/Documentation/i2c/busses/i2c-nforce2 @@ -7,10 +7,14 @@ Supported adapters: * nForce3 250Gb MCP 10de:00E4 * nForce4 MCP 10de:0052 * nForce4 MCP-04 10de:0034 - * nForce4 MCP51 10de:0264 - * nForce4 MCP55 10de:0368 - * nForce4 MCP61 10de:03EB - * nForce4 MCP65 10de:0446 + * nForce MCP51 10de:0264 + * nForce MCP55 10de:0368 + * nForce MCP61 10de:03EB + * nForce MCP65 10de:0446 + * nForce MCP67 10de:0542 + * nForce MCP73 10de:07D8 + * nForce MCP78S 10de:0752 + * nForce MCP79 10de:0AA2 Datasheet: not publicly available, but seems to be similar to the AMD-8111 SMBus 2.0 adapter. -- cgit v1.2.3 From 506a8b6c27cb08998dc13069fbdf6eb7ec748b99 Mon Sep 17 00:00:00 2001 From: Flavio Leitner Date: Sat, 28 Mar 2009 21:34:46 +0100 Subject: i2c-piix4: Add support for the Broadcom HT1100 chipset Add support for the Broadcom HT1100 LD chipset (SMBus function.) Signed-off-by: Flavio Leitner Signed-off-by: Jean Delvare --- Documentation/i2c/busses/i2c-piix4 | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/i2c/busses/i2c-piix4 b/Documentation/i2c/busses/i2c-piix4 index ef1efa79b1d..f889481762b 100644 --- a/Documentation/i2c/busses/i2c-piix4 +++ b/Documentation/i2c/busses/i2c-piix4 @@ -4,7 +4,7 @@ Supported adapters: * Intel 82371AB PIIX4 and PIIX4E * Intel 82443MX (440MX) Datasheet: Publicly available at the Intel website - * ServerWorks OSB4, CSB5, CSB6 and HT-1000 southbridges + * ServerWorks OSB4, CSB5, CSB6, HT-1000 and HT-1100 southbridges Datasheet: Only available via NDA from ServerWorks * ATI IXP200, IXP300, IXP400, SB600, SB700 and SB800 southbridges Datasheet: Not publicly available -- cgit v1.2.3 From d1881d3192a3d3e8dc4f255b03187f4c36cb0617 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Mon, 30 Mar 2009 21:55:25 -0600 Subject: lguest: barrier me harder Impact: barrier correctness in example launcher I doubt either lguest user will complain about performance. Reported-by: Christoph Hellwig Cc: Jens Axboe Signed-off-by: Rusty Russell --- Documentation/lguest/lguest.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'Documentation') diff --git a/Documentation/lguest/lguest.c b/Documentation/lguest/lguest.c index f2dbbf3bdea..d36fcc0f271 100644 --- a/Documentation/lguest/lguest.c +++ b/Documentation/lguest/lguest.c @@ -1630,6 +1630,13 @@ static bool service_io(struct device *dev) } } + /* OK, so we noted that it was pretty poor to use an fdatasync as a + * barrier. But Christoph Hellwig points out that we need a sync + * *afterwards* as well: "Barriers specify no reordering to the front + * or the back." And Jens Axboe confirmed it, so here we are: */ + if (out->type & VIRTIO_BLK_T_BARRIER) + fdatasync(vblk->fd); + /* We can't trigger an IRQ, because we're not the Launcher. It does * that when we tell it we're done. */ add_used(dev->vq, head, wlen); -- cgit v1.2.3 From afa5eb7c68689ced4284f01c96feed44a2d0a127 Mon Sep 17 00:00:00 2001 From: Jiri Slaby Date: Wed, 18 Mar 2009 09:13:37 +0100 Subject: HID: remove compat stuff This removal was scheduled and there is no problem with later distros to adapt for the new bus, thanks to aliases. module-init-tools map files are deprecated nowadays, so that the patch which introduced hid ones into the m-i-t won't be accepted and hence there is no reason for leaving compat stuff in. Signed-off-by: Jiri Slaby Cc: Jiri Kosina Signed-off-by: Jiri Kosina --- Documentation/feature-removal-schedule.txt | 7 ------- 1 file changed, 7 deletions(-) (limited to 'Documentation') diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 1135996bec8..fc5e85a5901 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -273,13 +273,6 @@ Who: Glauber Costa --------------------------- -What: remove HID compat support -When: 2.6.29 -Why: needed only as a temporary solution until distros fix themselves up -Who: Jiri Slaby - ---------------------------- - What: print_fn_descriptor_symbol() When: October 2009 Why: The %pF vsprintf format provides the same functionality in a -- cgit v1.2.3 From e3375ac767b847127df57d186a26abf83d055982 Mon Sep 17 00:00:00 2001 From: Pavel Machek Date: Sat, 10 Jan 2009 00:47:21 +0100 Subject: trivial: document ext3 semantics of 'ro' option a bit better ext3 has quite unexpected semantics or "ro" and defaults are not what they are documented to be, due to mkfs override. Signed-off-by: Pavel Machek Signed-off-by: "Theodore Ts'o" Signed-off-by: Jiri Kosina --- Documentation/filesystems/ext3.txt | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) (limited to 'Documentation') diff --git a/Documentation/filesystems/ext3.txt b/Documentation/filesystems/ext3.txt index e5f3833a6ef..570f9bd9be2 100644 --- a/Documentation/filesystems/ext3.txt +++ b/Documentation/filesystems/ext3.txt @@ -14,6 +14,11 @@ Options When mounting an ext3 filesystem, the following option are accepted: (*) == default +ro Mount filesystem read only. Note that ext3 will replay + the journal (and thus write to the partition) even when + mounted "read only". Mount options "ro,noload" can be + used to prevent writes to the filesystem. + journal=update Update the ext3 file system's journal to the current format. @@ -27,7 +32,9 @@ journal_dev=devnum When the external journal device's major/minor numbers identified through its new major/minor numbers encoded in devnum. -noload Don't load the journal on mounting. +noload Don't load the journal on mounting. Note that this forces + mount of inconsistent filesystem, which can lead to + various problems. data=journal All data are committed into the journal prior to being written into the main file system. @@ -92,9 +99,12 @@ nocheck debug Extra debugging information is sent to syslog. -errors=remount-ro(*) Remount the filesystem read-only on an error. +errors=remount-ro Remount the filesystem read-only on an error. errors=continue Keep going on a filesystem error. errors=panic Panic and halt the machine if an error occurs. + (These mount options override the errors behavior + specified in the superblock, which can be + configured using tune2fs.) data_err=ignore(*) Just print an error message if an error occurs in a file data buffer in ordered mode. -- cgit v1.2.3 From caa790ba6cb88dccfab356960d93e2f4e0bd8704 Mon Sep 17 00:00:00 2001 From: Chris Samuel Date: Sat, 17 Jan 2009 00:01:18 +1100 Subject: trivial: cgroups: documentation typo and spelling corrections Minor typo and spelling corrections fixed whilst reading to learn about cgroups capabilities. Signed-off-by: Chris Samuel Acked-by: Paul Menage Signed-off-by: Jiri Kosina --- Documentation/cgroups/cgroups.txt | 10 +++++----- Documentation/cgroups/cpusets.txt | 12 ++++++------ Documentation/cgroups/devices.txt | 2 +- Documentation/cgroups/memory.txt | 2 +- 4 files changed, 13 insertions(+), 13 deletions(-) (limited to 'Documentation') diff --git a/Documentation/cgroups/cgroups.txt b/Documentation/cgroups/cgroups.txt index 93feb844448..f4f5ee97d4d 100644 --- a/Documentation/cgroups/cgroups.txt +++ b/Documentation/cgroups/cgroups.txt @@ -56,7 +56,7 @@ hierarchy, and a set of subsystems; each subsystem has system-specific state attached to each cgroup in the hierarchy. Each hierarchy has an instance of the cgroup virtual filesystem associated with it. -At any one time there may be multiple active hierachies of task +At any one time there may be multiple active hierarchies of task cgroups. Each hierarchy is a partition of all tasks in the system. User level code may create and destroy cgroups by name in an @@ -124,10 +124,10 @@ following lines: / \ Prof (15%) students (5%) -Browsers like firefox/lynx go into the WWW network class, while (k)nfsd go +Browsers like Firefox/Lynx go into the WWW network class, while (k)nfsd go into NFS network class. -At the same time firefox/lynx will share an appropriate CPU/Memory class +At the same time Firefox/Lynx will share an appropriate CPU/Memory class depending on who launched it (prof/student). With the ability to classify tasks differently for different resources @@ -325,7 +325,7 @@ and then start a subshell 'sh' in that cgroup: Creating, modifying, using the cgroups can be done through the cgroup virtual filesystem. -To mount a cgroup hierarchy will all available subsystems, type: +To mount a cgroup hierarchy with all available subsystems, type: # mount -t cgroup xxx /dev/cgroup The "xxx" is not interpreted by the cgroup code, but will appear in @@ -521,7 +521,7 @@ always handled well. void post_clone(struct cgroup_subsys *ss, struct cgroup *cgrp) (cgroup_mutex held by caller) -Called at the end of cgroup_clone() to do any paramater +Called at the end of cgroup_clone() to do any parameter initialization which might be required before a task could attach. For example in cpusets, no task may attach before 'cpus' and 'mems' are set up. diff --git a/Documentation/cgroups/cpusets.txt b/Documentation/cgroups/cpusets.txt index 0611e9528c7..f9ca389dddf 100644 --- a/Documentation/cgroups/cpusets.txt +++ b/Documentation/cgroups/cpusets.txt @@ -131,7 +131,7 @@ Cpusets extends these two mechanisms as follows: - The hierarchy of cpusets can be mounted at /dev/cpuset, for browsing and manipulation from user space. - A cpuset may be marked exclusive, which ensures that no other - cpuset (except direct ancestors and descendents) may contain + cpuset (except direct ancestors and descendants) may contain any overlapping CPUs or Memory Nodes. - You can list all the tasks (by pid) attached to any cpuset. @@ -226,7 +226,7 @@ nodes with memory--using the cpuset_track_online_nodes() hook. -------------------------------- If a cpuset is cpu or mem exclusive, no other cpuset, other than -a direct ancestor or descendent, may share any of the same CPUs or +a direct ancestor or descendant, may share any of the same CPUs or Memory Nodes. A cpuset that is mem_exclusive *or* mem_hardwall is "hardwalled", @@ -427,7 +427,7 @@ child cpusets have this flag enabled. When doing this, you don't usually want to leave any unpinned tasks in the top cpuset that might use non-trivial amounts of CPU, as such tasks may be artificially constrained to some subset of CPUs, depending on -the particulars of this flag setting in descendent cpusets. Even if +the particulars of this flag setting in descendant cpusets. Even if such a task could use spare CPU cycles in some other CPUs, the kernel scheduler might not consider the possibility of load balancing that task to that underused CPU. @@ -531,9 +531,9 @@ be idle. Of course it takes some searching cost to find movable tasks and/or idle CPUs, the scheduler might not search all CPUs in the domain -everytime. In fact, in some architectures, the searching ranges on +every time. In fact, in some architectures, the searching ranges on events are limited in the same socket or node where the CPU locates, -while the load balance on tick searchs all. +while the load balance on tick searches all. For example, assume CPU Z is relatively far from CPU X. Even if CPU Z is idle while CPU X and the siblings are busy, scheduler can't migrate @@ -601,7 +601,7 @@ its new cpuset, then the task will continue to use whatever subset of MPOL_BIND nodes are still allowed in the new cpuset. If the task was using MPOL_BIND and now none of its MPOL_BIND nodes are allowed in the new cpuset, then the task will be essentially treated as if it -was MPOL_BIND bound to the new cpuset (even though its numa placement, +was MPOL_BIND bound to the new cpuset (even though its NUMA placement, as queried by get_mempolicy(), doesn't change). If a task is moved from one cpuset to another, then the kernel will adjust the tasks memory placement, as above, the next time that the kernel attempts diff --git a/Documentation/cgroups/devices.txt b/Documentation/cgroups/devices.txt index 7cc6e6a6067..57ca4c89fe5 100644 --- a/Documentation/cgroups/devices.txt +++ b/Documentation/cgroups/devices.txt @@ -42,7 +42,7 @@ suffice, but we can decide the best way to adequately restrict movement as people get some experience with this. We may just want to require CAP_SYS_ADMIN, which at least is a separate bit from CAP_MKNOD. We may want to just refuse moving to a cgroup which -isn't a descendent of the current one. Or we may want to use +isn't a descendant of the current one. Or we may want to use CAP_MAC_ADMIN, since we really are trying to lock down root. CAP_SYS_ADMIN is needed to modify the whitelist or move another diff --git a/Documentation/cgroups/memory.txt b/Documentation/cgroups/memory.txt index e1501964df1..a98a7fe7aab 100644 --- a/Documentation/cgroups/memory.txt +++ b/Documentation/cgroups/memory.txt @@ -302,7 +302,7 @@ will be charged as a new owner of it. unevictable - # of pages cannot be reclaimed.(mlocked etc) Below is depend on CONFIG_DEBUG_VM. - inactive_ratio - VM inernal parameter. (see mm/page_alloc.c) + inactive_ratio - VM internal parameter. (see mm/page_alloc.c) recent_rotated_anon - VM internal parameter. (see mm/vmscan.c) recent_rotated_file - VM internal parameter. (see mm/vmscan.c) recent_scanned_anon - VM internal parameter. (see mm/vmscan.c) -- cgit v1.2.3 From 877d03105d04b2c13e241130277fa69c8d2564f0 Mon Sep 17 00:00:00 2001 From: Nick Andrew Date: Mon, 26 Jan 2009 11:06:57 +0100 Subject: trivial: Fix misspelling of firmware Fix misspelling of firmware. Signed-off-by: Nick Andrew Signed-off-by: Jiri Kosina --- Documentation/ia64/kvm.txt | 2 +- Documentation/powerpc/dts-bindings/fsl/cpm_qe/qe/firmware.txt | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'Documentation') diff --git a/Documentation/ia64/kvm.txt b/Documentation/ia64/kvm.txt index 84f7cb3d5be..ffb5c80bec3 100644 --- a/Documentation/ia64/kvm.txt +++ b/Documentation/ia64/kvm.txt @@ -42,7 +42,7 @@ Note: For step 2, please make sure that host page size == TARGET_PAGE_SIZE of qe hg clone http://xenbits.xensource.com/ext/efi-vfirmware.hg you can get the firmware's binary in the directory of efi-vfirmware.hg/binaries. - (3) Rename the firware you owned to Flash.fd, and copy it to /usr/local/share/qemu + (3) Rename the firmware you owned to Flash.fd, and copy it to /usr/local/share/qemu 4. Boot up Linux or Windows guests: 4.1 Create or install a image for guest boot. If you have xen experience, it should be easy. diff --git a/Documentation/powerpc/dts-bindings/fsl/cpm_qe/qe/firmware.txt b/Documentation/powerpc/dts-bindings/fsl/cpm_qe/qe/firmware.txt index 6c238f59b2a..249db3a15d1 100644 --- a/Documentation/powerpc/dts-bindings/fsl/cpm_qe/qe/firmware.txt +++ b/Documentation/powerpc/dts-bindings/fsl/cpm_qe/qe/firmware.txt @@ -1,6 +1,6 @@ * Uploaded QE firmware - If a new firwmare has been uploaded to the QE (usually by the + If a new firmware has been uploaded to the QE (usually by the boot loader), then a 'firmware' child node should be added to the QE node. This node provides information on the uploaded firmware that device drivers may need. -- cgit v1.2.3 From 6d5e147dd034d9ceedc89fe39f4284700944f0c8 Mon Sep 17 00:00:00 2001 From: Thadeu Lima de Souza Cascardo Date: Tue, 3 Feb 2009 11:57:13 +0100 Subject: trivial: Give the right path in Documentation example While the Documentation example creates /cgroup/test, it removes /test/cgroup, which is clearly not the intended path. Change that to /cgroup/test. Acked-by: KAMEZAWA Hiroyuki Signed-off-by: Thadeu Lima de Souza Cascardo Signed-off-by: Jiri Kosina --- Documentation/cgroups/memcg_test.txt | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/cgroups/memcg_test.txt b/Documentation/cgroups/memcg_test.txt index 523a9c16c40..a9263596f8d 100644 --- a/Documentation/cgroups/memcg_test.txt +++ b/Documentation/cgroups/memcg_test.txt @@ -356,7 +356,7 @@ Under below explanation, we assume CONFIG_MEM_RES_CTRL_SWAP=y. (Shell-B) # move all tasks in /cgroup/test to /cgroup # /sbin/swapoff -a - # rmdir /test/cgroup + # rmdir /cgroup/test # kill malloc task. Of course, tmpfs v.s. swapoff test should be tested, too. -- cgit v1.2.3 From 21acb9caa2e30b100e9a1943d995bb99d40f4035 Mon Sep 17 00:00:00 2001 From: Thadeu Lima de Souza Cascardo Date: Wed, 4 Feb 2009 10:12:08 +0100 Subject: trivial: fix where cgroup documentation is not correctly referred to cgroup documentation was moved to Documentation/cgroups/. There are some places that still refer to Documentation/controllers/, Documentation/cgroups.txt and Documentation/cpusets.txt. Fix those. Signed-off-by: Thadeu Lima de Souza Cascardo Reviewed-by: Li Zefan Acked-by: Paul Menage Signed-off-by: Jiri Kosina --- Documentation/00-INDEX | 4 ++-- Documentation/cgroups/00-INDEX | 18 ++++++++++++++++++ Documentation/kernel-parameters.txt | 4 ++-- Documentation/scheduler/sched-rt-group.txt | 2 +- Documentation/vm/numa_memory_policy.txt | 3 ++- Documentation/vm/page_migration | 3 ++- Documentation/x86/x86_64/fake-numa-for-cpusets | 5 +++-- 7 files changed, 30 insertions(+), 9 deletions(-) create mode 100644 Documentation/cgroups/00-INDEX (limited to 'Documentation') diff --git a/Documentation/00-INDEX b/Documentation/00-INDEX index 2a39aeba146..d05737aaa84 100644 --- a/Documentation/00-INDEX +++ b/Documentation/00-INDEX @@ -86,6 +86,8 @@ cachetlb.txt - describes the cache/TLB flushing interfaces Linux uses. cdrom/ - directory with information on the CD-ROM drivers that Linux has. +cgroups/ + - cgroups features, including cpusets and memory controller. connector/ - docs on the netlink based userspace<->kernel space communication mod. console/ @@ -98,8 +100,6 @@ cpu-load.txt - document describing how CPU load statistics are collected. cpuidle/ - info on CPU_IDLE, CPU idle state management subsystem. -cpusets.txt - - documents the cpusets feature; assign CPUs and Mem to a set of tasks. cputopology.txt - documentation on how CPU topology info is exported via sysfs. cris/ diff --git a/Documentation/cgroups/00-INDEX b/Documentation/cgroups/00-INDEX new file mode 100644 index 00000000000..3f58fa3d6d0 --- /dev/null +++ b/Documentation/cgroups/00-INDEX @@ -0,0 +1,18 @@ +00-INDEX + - this file +cgroups.txt + - Control Groups definition, implementation details, examples and API. +cpuacct.txt + - CPU Accounting Controller; account CPU usage for groups of tasks. +cpusets.txt + - documents the cpusets feature; assign CPUs and Mem to a set of tasks. +devices.txt + - Device Whitelist Controller; description, interface and security. +freezer-subsystem.txt + - checkpointing; rationale to not use signals, interface. +memcg_test.txt + - Memory Resource Controller; implementation details. +memory.txt + - Memory Resource Controller; design, accounting, interface, testing. +resource_counter.txt + - Resource Counter API. diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index be3bde51b56..755def2cb07 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1593,7 +1593,7 @@ and is between 256 and 4096 characters. It is defined in the file nosoftlockup [KNL] Disable the soft-lockup detector. noswapaccount [KNL] Disable accounting of swap in memory resource - controller. (See Documentation/controllers/memory.txt) + controller. (See Documentation/cgroups/memory.txt) nosync [HW,M68K] Disables sync negotiation for all devices. @@ -1932,7 +1932,7 @@ and is between 256 and 4096 characters. It is defined in the file relax_domain_level= [KNL, SMP] Set scheduler's default relax_domain_level. - See Documentation/cpusets.txt. + See Documentation/cgroups/cpusets.txt. reserve= [KNL,BUGS] Force the kernel to ignore some iomem area diff --git a/Documentation/scheduler/sched-rt-group.txt b/Documentation/scheduler/sched-rt-group.txt index 3ef339f491e..5ba4d3fc625 100644 --- a/Documentation/scheduler/sched-rt-group.txt +++ b/Documentation/scheduler/sched-rt-group.txt @@ -126,7 +126,7 @@ This uses the /cgroup virtual file system and "/cgroup//cpu.rt_runtime_u to control the CPU time reserved for each control group instead. For more information on working with control groups, you should read -Documentation/cgroups.txt as well. +Documentation/cgroups/cgroups.txt as well. Group settings are checked against the following limits in order to keep the configuration schedulable: diff --git a/Documentation/vm/numa_memory_policy.txt b/Documentation/vm/numa_memory_policy.txt index 6aaaeb38730..be45dbb9d7f 100644 --- a/Documentation/vm/numa_memory_policy.txt +++ b/Documentation/vm/numa_memory_policy.txt @@ -8,7 +8,8 @@ The current memory policy support was added to Linux 2.6 around May 2004. This document attempts to describe the concepts and APIs of the 2.6 memory policy support. -Memory policies should not be confused with cpusets (Documentation/cpusets.txt) +Memory policies should not be confused with cpusets +(Documentation/cgroups/cpusets.txt) which is an administrative mechanism for restricting the nodes from which memory may be allocated by a set of processes. Memory policies are a programming interface that a NUMA-aware application can take advantage of. When diff --git a/Documentation/vm/page_migration b/Documentation/vm/page_migration index d5fdfd34bba..6513fe2d90b 100644 --- a/Documentation/vm/page_migration +++ b/Documentation/vm/page_migration @@ -37,7 +37,8 @@ locations. Larger installations usually partition the system using cpusets into sections of nodes. Paul Jackson has equipped cpusets with the ability to -move pages when a task is moved to another cpuset (See ../cpusets.txt). +move pages when a task is moved to another cpuset (See +Documentation/cgroups/cpusets.txt). Cpusets allows the automation of process locality. If a task is moved to a new cpuset then also all its pages are moved with it so that the performance of the process does not sink dramatically. Also the pages diff --git a/Documentation/x86/x86_64/fake-numa-for-cpusets b/Documentation/x86/x86_64/fake-numa-for-cpusets index 33bb5665599..0f11d9becb0 100644 --- a/Documentation/x86/x86_64/fake-numa-for-cpusets +++ b/Documentation/x86/x86_64/fake-numa-for-cpusets @@ -7,7 +7,8 @@ you can create fake NUMA nodes that represent contiguous chunks of memory and assign them to cpusets and their attached tasks. This is a way of limiting the amount of system memory that are available to a certain class of tasks. -For more information on the features of cpusets, see Documentation/cpusets.txt. +For more information on the features of cpusets, see +Documentation/cgroups/cpusets.txt. There are a number of different configurations you can use for your needs. For more information on the numa=fake command line option and its various ways of configuring fake nodes, see Documentation/x86/x86_64/boot-options.txt. @@ -32,7 +33,7 @@ A machine may be split as follows with "numa=fake=4*512," as reported by dmesg: On node 3 totalpages: 131072 Now following the instructions for mounting the cpusets filesystem from -Documentation/cpusets.txt, you can assign fake nodes (i.e. contiguous memory +Documentation/cgroups/cpusets.txt, you can assign fake nodes (i.e. contiguous memory address spaces) to individual cpusets: [root@xroads /]# mkdir exampleset -- cgit v1.2.3 From f5360bdc5539ccd7644df7acf27e8c740ba8cf6e Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Thu, 15 Jan 2009 06:09:05 -0300 Subject: V4L/DVB (10252): v4l2 doc: explain why v4l2_device_unregister_subdev() has to be called. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/v4l2-framework.txt | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'Documentation') diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt index ff124374e9b..cc350624237 100644 --- a/Documentation/video4linux/v4l2-framework.txt +++ b/Documentation/video4linux/v4l2-framework.txt @@ -340,6 +340,12 @@ Make sure to call v4l2_device_unregister_subdev(sd) when the remove() callback is called. This will unregister the sub-device from the bridge driver. It is safe to call this even if the sub-device was never registered. +You need to do this because when the bridge driver destroys the i2c adapter +the remove() callbacks are called of the i2c devices on that adapter. +After that the corresponding v4l2_subdev structures are invalid, so they +have to be unregistered first. Calling v4l2_device_unregister_subdev(sd) +from the remove() callback ensures that this is always done correctly. + The bridge driver also has some helper functions it can use: -- cgit v1.2.3 From c76b638ca20d6cbf91ee017c6f2afd7d3fcd57ff Mon Sep 17 00:00:00 2001 From: Antoine Jacquet Date: Sat, 17 Jan 2009 22:49:08 -0300 Subject: V4L/DVB (10263): zr364xx: add support for Aiptek DV T300 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Tested-by: Hámorszky Balázs Signed-off-by: Antoine Jacquet Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/zr364xx.txt | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/video4linux/zr364xx.txt b/Documentation/video4linux/zr364xx.txt index 5c81e3ae645..7f3d1955d21 100644 --- a/Documentation/video4linux/zr364xx.txt +++ b/Documentation/video4linux/zr364xx.txt @@ -65,3 +65,4 @@ Vendor Product Distributor Model 0x06d6 0x003b Trust Powerc@m 970Z 0x0a17 0x004e Pentax Optio 50 0x041e 0x405d Creative DiVi CAM 516 +0x08ca 0x2102 Aiptek DV T300 -- cgit v1.2.3 From 96318d0cca02a91b22a2e1a1097ffeea0b3becae Mon Sep 17 00:00:00 2001 From: "Igor M. Liplianin" Date: Sat, 17 Jan 2009 12:11:20 -0300 Subject: V4L/DVB (10266): Add support for TurboSight TBS6920 DVB-S2 PCI-e card. TurboSight TBS6920 DVB-S2 PCI-e card contains cx23885 PCI-e bridge and cx24116 demodulator. http://www.linuxtv.org/wiki/index.php/TBS_6920 The card tested by me (Igor). Signed-off-by: Igor M. Liplianin Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/CARDLIST.cx23885 | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/video4linux/CARDLIST.cx23885 b/Documentation/video4linux/CARDLIST.cx23885 index 35ea130e989..3af13a06ee6 100644 --- a/Documentation/video4linux/CARDLIST.cx23885 +++ b/Documentation/video4linux/CARDLIST.cx23885 @@ -12,3 +12,4 @@ 11 -> DViCO FusionHDTV DVB-T Dual Express [18ac:db78] 12 -> Leadtek Winfast PxDVR3200 H [107d:6681] 13 -> Compro VideoMate E650F [185b:e800] + 14 -> TurboSight TBS 6920 [6920:8888] -- cgit v1.2.3 From 579943f5487baa7f9fd8e3189a4f357d6b06c76d Mon Sep 17 00:00:00 2001 From: "Igor M. Liplianin" Date: Sat, 17 Jan 2009 12:18:26 -0300 Subject: V4L/DVB (10267): Add support for TeVii S470 DVB-S2 PCI-e card. TeVii S470 DVB-S2 PCI-e card contains cx23885 PCI-e bridge and cx24116 demodulator. http://www.linuxtv.org/wiki/index.php/TeVii_S470 The card tested by me (Igor). Signed-off-by: Igor M. Liplianin Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/CARDLIST.cx23885 | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/video4linux/CARDLIST.cx23885 b/Documentation/video4linux/CARDLIST.cx23885 index 3af13a06ee6..43d290ea75b 100644 --- a/Documentation/video4linux/CARDLIST.cx23885 +++ b/Documentation/video4linux/CARDLIST.cx23885 @@ -13,3 +13,4 @@ 12 -> Leadtek Winfast PxDVR3200 H [107d:6681] 13 -> Compro VideoMate E650F [185b:e800] 14 -> TurboSight TBS 6920 [6920:8888] + 15 -> TeVii S470 [d470:9022] -- cgit v1.2.3 From c9b8b04b267f9a7e472daa06cdf6d4963d503d1f Mon Sep 17 00:00:00 2001 From: "Igor M. Liplianin" Date: Sat, 17 Jan 2009 12:23:31 -0300 Subject: V4L/DVB (10269): Add support for DVBWorld DVBS2 PCI-e 2005. DVBWorld DVBS2 PCI-e 2005 card contains cx23885 PCI-e bridge and cx24116 demodulator. http://www.linuxtv.org/wiki/index.php/DVBWorld_DVB-S2_2005_PCI-Express_Card The card tested by me (Igor). Signed-off-by: Igor M. Liplianin Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/CARDLIST.cx23885 | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/video4linux/CARDLIST.cx23885 b/Documentation/video4linux/CARDLIST.cx23885 index 43d290ea75b..5937ff958f0 100644 --- a/Documentation/video4linux/CARDLIST.cx23885 +++ b/Documentation/video4linux/CARDLIST.cx23885 @@ -14,3 +14,4 @@ 13 -> Compro VideoMate E650F [185b:e800] 14 -> TurboSight TBS 6920 [6920:8888] 15 -> TeVii S470 [d470:9022] + 16 -> DVBWorld DVB-S2 2005 [0001:2005] -- cgit v1.2.3 From ade0815c16734e8c25dbac9faf5b5d63bcccd533 Mon Sep 17 00:00:00 2001 From: Douglas Kosovic Date: Thu, 22 Jan 2009 23:07:26 -0300 Subject: V4L/DVB (10299): bttv: Add support for IVCE-8784 support for V4L2 bttv driver It's a quad Bt878 PCI-e x1 capture board that's basically the same as the IVC-200 (quad Bt878 PCI) capture board that's currently supported in the V4L2 bttv driver. Manufacturer's web page for IVCE-8784 with photo and info: http://www.iei.com.tw/en/product_IPC.asp?model=IVCE-8784 Signed-off-by: Douglas Kosovic Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/CARDLIST.bttv | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/video4linux/CARDLIST.bttv b/Documentation/video4linux/CARDLIST.bttv index 0d93fa1ac25..4dfe6264137 100644 --- a/Documentation/video4linux/CARDLIST.bttv +++ b/Documentation/video4linux/CARDLIST.bttv @@ -154,3 +154,4 @@ 153 -> PHYTEC VD-012 (bt878) 154 -> PHYTEC VD-012-X1 (bt878) 155 -> PHYTEC VD-012-X2 (bt878) +156 -> IVCE-8784 [0000:f050,0001:f050,0002:f050,0003:f050] -- cgit v1.2.3 From f7fe3e6f3c3e9ef6ba5ca187b514d225296d18dd Mon Sep 17 00:00:00 2001 From: Douglas Schilling Landgraf Date: Mon, 19 Jan 2009 09:31:55 -0300 Subject: V4L/DVB (10323): em28xx: Add entry for GADMEI TVR200 Added entry for GADMEI TVR200. Thanks to Yohanes Nugroho for testing and data collection. Signed-off-by: Douglas Schilling Landgraf Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/CARDLIST.em28xx | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/video4linux/CARDLIST.em28xx b/Documentation/video4linux/CARDLIST.em28xx index 75bded8a4aa..f7a7f48f4d7 100644 --- a/Documentation/video4linux/CARDLIST.em28xx +++ b/Documentation/video4linux/CARDLIST.em28xx @@ -58,3 +58,4 @@ 58 -> Compro VideoMate ForYou/Stereo (em2820/em2840) [185b:2041] 60 -> Hauppauge WinTV HVR 850 (em2883) [2040:651f] 61 -> Pixelview PlayTV Box 4 USB 2.0 (em2820/em2840) + 62 -> Gadmei TVR200 (em2820/em2840) -- cgit v1.2.3 From d661e62205498ce6518b9859bc30444e59737d8b Mon Sep 17 00:00:00 2001 From: Kyle Guinn Date: Fri, 16 Jan 2009 05:36:14 -0300 Subject: V4L/DVB (10366): gspca - mr97310a: New subdriver. This patch adds support for USB webcams based on the MR97310A chip. It was tested with an Aiptek PenCam VGA+ webcam. Signed-off-by: Kyle Guinn Signed-off-by: Jean-Francois Moine Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/gspca.txt | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/video4linux/gspca.txt b/Documentation/video4linux/gspca.txt index 1c58a763014..af80c334456 100644 --- a/Documentation/video4linux/gspca.txt +++ b/Documentation/video4linux/gspca.txt @@ -193,6 +193,7 @@ spca500 084d:0003 D-Link DSC-350 spca500 08ca:0103 Aiptek PocketDV sunplus 08ca:0104 Aiptek PocketDVII 1.3 sunplus 08ca:0106 Aiptek Pocket DV3100+ +mr97310a 08ca:0111 Aiptek PenCam VGA+ sunplus 08ca:2008 Aiptek Mini PenCam 2 M sunplus 08ca:2010 Aiptek PocketCam 3M sunplus 08ca:2016 Aiptek PocketCam 2 Mega -- cgit v1.2.3 From db91235ee8350149213435c4cf178a7627c968b9 Mon Sep 17 00:00:00 2001 From: Lierdakil Date: Sun, 25 Jan 2009 14:37:26 -0300 Subject: V4L/DVB (10388): gspca - pac207: Webcam 093a:2474 added. Signed-off-by: Lierdakil Signed-off-by: Jean-Francois Moine Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/gspca.txt | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/video4linux/gspca.txt b/Documentation/video4linux/gspca.txt index af80c334456..3136c80280b 100644 --- a/Documentation/video4linux/gspca.txt +++ b/Documentation/video4linux/gspca.txt @@ -216,6 +216,7 @@ pac207 093a:2468 PAC207 pac207 093a:2470 Genius GF112 pac207 093a:2471 Genius VideoCam ge111 pac207 093a:2472 Genius VideoCam ge110 +pac207 093a:2474 Genius iLook 111 pac207 093a:2476 Genius e-Messenger 112 pac7311 093a:2600 PAC7311 Typhoon pac7311 093a:2601 Philips SPC 610 NC -- cgit v1.2.3 From de43cd37b88408280cb4e533c9fee820fb8d5c73 Mon Sep 17 00:00:00 2001 From: Jean-Francois Moine Date: Thu, 29 Jan 2009 06:02:37 -0300 Subject: V4L/DVB (10421): gspca - documentation: Add the webcam 041e:405b. Signed-off-by: Jean-Francois Moine Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/gspca.txt | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/video4linux/gspca.txt b/Documentation/video4linux/gspca.txt index 3136c80280b..12c8ff7058b 100644 --- a/Documentation/video4linux/gspca.txt +++ b/Documentation/video4linux/gspca.txt @@ -32,6 +32,7 @@ spca561 041e:403b Creative Webcam Vista (VF0010) zc3xx 041e:4051 Creative Live!Cam Notebook Pro (VF0250) ov519 041e:4052 Creative Live! VISTA IM zc3xx 041e:4053 Creative Live!Cam Video IM +vc032x 041e:405b Creative Live! Cam Notebook Ultra (VC0130) ov519 041e:405f Creative Live! VISTA VF0330 ov519 041e:4060 Creative Live! VISTA VF0350 ov519 041e:4061 Creative Live! VISTA VF0400 -- cgit v1.2.3 From d7493e518fa98d2c30c545c518df075903bae513 Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Fri, 6 Feb 2009 15:35:22 -0300 Subject: V4L/DVB (10487): doc: update hm12 documentation. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/cx2341x/README.hm12 | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'Documentation') diff --git a/Documentation/video4linux/cx2341x/README.hm12 b/Documentation/video4linux/cx2341x/README.hm12 index 0e213ed095e..b36148ea075 100644 --- a/Documentation/video4linux/cx2341x/README.hm12 +++ b/Documentation/video4linux/cx2341x/README.hm12 @@ -32,6 +32,10 @@ Y, U and V planes. This code assumes frames of 720x576 (PAL) pixels. The width of a frame is always 720 pixels, regardless of the actual specified width. +If the height is not a multiple of 32 lines, then the captured video is +missing macroblocks at the end and is unusable. So the height must be a +multiple of 32. + -------------------------------------------------------------------------- #include -- cgit v1.2.3 From 89aec3e1baaddeaa5636487f0e23f807eb758168 Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Sat, 7 Feb 2009 07:07:04 -0300 Subject: V4L/DVB (10489): doc: use consistent naming conventions for vdev and v4l2_dev. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/v4l2-framework.txt | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) (limited to 'Documentation') diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt index cc350624237..73f9b642392 100644 --- a/Documentation/video4linux/v4l2-framework.txt +++ b/Documentation/video4linux/v4l2-framework.txt @@ -134,7 +134,7 @@ The recommended approach is as follows: static atomic_t drv_instance = ATOMIC_INIT(0); -static int __devinit drv_probe(struct pci_dev *dev, +static int __devinit drv_probe(struct pci_dev *pdev, const struct pci_device_id *pci_id) { ... @@ -218,7 +218,7 @@ to add new ops and categories. A sub-device driver initializes the v4l2_subdev struct using: - v4l2_subdev_init(subdev, &ops); + v4l2_subdev_init(sd, &ops); Afterwards you need to initialize subdev->name with a unique name and set the module owner. This is done for you if you use the i2c helper functions. @@ -226,7 +226,7 @@ module owner. This is done for you if you use the i2c helper functions. A device (bridge) driver needs to register the v4l2_subdev with the v4l2_device: - int err = v4l2_device_register_subdev(device, subdev); + int err = v4l2_device_register_subdev(v4l2_dev, sd); This can fail if the subdev module disappeared before it could be registered. After this function was called successfully the subdev->dev field points to @@ -234,17 +234,17 @@ the v4l2_device. You can unregister a sub-device using: - v4l2_device_unregister_subdev(subdev); + v4l2_device_unregister_subdev(sd); -Afterwards the subdev module can be unloaded and subdev->dev == NULL. +Afterwards the subdev module can be unloaded and sd->dev == NULL. You can call an ops function either directly: - err = subdev->ops->core->g_chip_ident(subdev, &chip); + err = sd->ops->core->g_chip_ident(sd, &chip); but it is better and easier to use this macro: - err = v4l2_subdev_call(subdev, core, g_chip_ident, &chip); + err = v4l2_subdev_call(sd, core, g_chip_ident, &chip); The macro will to the right NULL pointer checks and returns -ENODEV if subdev is NULL, -ENOIOCTLCMD if either subdev->core or subdev->core->g_chip_ident is @@ -252,12 +252,12 @@ NULL, or the actual result of the subdev->ops->core->g_chip_ident ops. It is also possible to call all or a subset of the sub-devices: - v4l2_device_call_all(dev, 0, core, g_chip_ident, &chip); + v4l2_device_call_all(v4l2_dev, 0, core, g_chip_ident, &chip); Any subdev that does not support this ops is skipped and error results are ignored. If you want to check for errors use this: - err = v4l2_device_call_until_err(dev, 0, core, g_chip_ident, &chip); + err = v4l2_device_call_until_err(v4l2_dev, 0, core, g_chip_ident, &chip); Any error except -ENOIOCTLCMD will exit the loop with that error. If no errors (except -ENOIOCTLCMD) occured, then 0 is returned. @@ -505,8 +505,8 @@ There are a few useful helper functions: You can set/get driver private data in the video_device struct using: -void *video_get_drvdata(struct video_device *dev); -void video_set_drvdata(struct video_device *dev, void *data); +void *video_get_drvdata(struct video_device *vdev); +void video_set_drvdata(struct video_device *vdev, void *data); Note that you can safely call video_set_drvdata() before calling video_register_device(). -- cgit v1.2.3 From 0bf4f6ce6d43b135867a78fa1b4ac58e22d2e329 Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Wed, 11 Feb 2009 14:13:20 -0300 Subject: V4L/DVB (10514): em28xx: Add support for Kaiomy TVnPC U2 stick Thanks to Peter Senna Tschudin for borrow me one of those devices. Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/CARDLIST.em28xx | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/video4linux/CARDLIST.em28xx b/Documentation/video4linux/CARDLIST.em28xx index f7a7f48f4d7..e914b137434 100644 --- a/Documentation/video4linux/CARDLIST.em28xx +++ b/Documentation/video4linux/CARDLIST.em28xx @@ -57,5 +57,6 @@ 57 -> Kworld PlusTV HD Hybrid 330 (em2883) [eb1a:a316] 58 -> Compro VideoMate ForYou/Stereo (em2820/em2840) [185b:2041] 60 -> Hauppauge WinTV HVR 850 (em2883) [2040:651f] + 61 -> Kaiomy TVnPC U2 (em2860) [eb1a:e303] 61 -> Pixelview PlayTV Box 4 USB 2.0 (em2820/em2840) 62 -> Gadmei TVR200 (em2820/em2840) -- cgit v1.2.3 From 56ee38071fe0cf1746d53c5b40a46a835b24fbe4 Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Wed, 11 Feb 2009 14:18:36 -0300 Subject: V4L/DVB (10516): em28xx: Add support for Easy Cap Capture DC-60 Thanks to Peter Senna Tschudin for borrow me one of those devices. Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/CARDLIST.em28xx | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/video4linux/CARDLIST.em28xx b/Documentation/video4linux/CARDLIST.em28xx index e914b137434..b336dcab139 100644 --- a/Documentation/video4linux/CARDLIST.em28xx +++ b/Documentation/video4linux/CARDLIST.em28xx @@ -57,6 +57,7 @@ 57 -> Kworld PlusTV HD Hybrid 330 (em2883) [eb1a:a316] 58 -> Compro VideoMate ForYou/Stereo (em2820/em2840) [185b:2041] 60 -> Hauppauge WinTV HVR 850 (em2883) [2040:651f] - 61 -> Kaiomy TVnPC U2 (em2860) [eb1a:e303] 61 -> Pixelview PlayTV Box 4 USB 2.0 (em2820/em2840) 62 -> Gadmei TVR200 (em2820/em2840) + 63 -> Kaiomy TVnPC U2 (em2860) [eb1a:e303] + 64 -> Easy Cap Capture DC-60 (em2860) -- cgit v1.2.3 From 7aa0eabde08259c47586df934921c67cff36e7dc Mon Sep 17 00:00:00 2001 From: Douglas Schilling Landgraf Date: Tue, 10 Feb 2009 22:00:06 -0300 Subject: V4L/DVB (10524): em28xx: Add DVC 101 model to Pinnacle Dazzle description Added DVC 101 model to Pinnacle Dazzle description Signed-off-by: Douglas Schilling Landgraf Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/CARDLIST.em28xx | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/video4linux/CARDLIST.em28xx b/Documentation/video4linux/CARDLIST.em28xx index b336dcab139..69601089f0a 100644 --- a/Documentation/video4linux/CARDLIST.em28xx +++ b/Documentation/video4linux/CARDLIST.em28xx @@ -7,7 +7,7 @@ 6 -> Terratec Cinergy 200 USB (em2800) 7 -> Leadtek Winfast USB II (em2800) [0413:6023] 8 -> Kworld USB2800 (em2800) - 9 -> Pinnacle Dazzle DVC 90/DVC 100 (em2820/em2840) [2304:0207,2304:021a] + 9 -> Pinnacle Dazzle DVC 90/DVC 100/DVC 101 (em2820/em2840) [2304:0207,2304:021a] 10 -> Hauppauge WinTV HVR 900 (em2880) [2040:6500] 11 -> Terratec Hybrid XS (em2880) [0ccd:0042] 12 -> Kworld PVR TV 2800 RF (em2820/em2840) -- cgit v1.2.3 From f74a61e3c6f218053742c2caf3e247fb41bf395e Mon Sep 17 00:00:00 2001 From: Indika Katugampala Date: Wed, 11 Feb 2009 11:13:05 -0300 Subject: V4L/DVB (10528): em28xx: support added for IO-DATA GV/MVP SZ - EMPIA-2820 chipset [dougsland@redhat.com: Fixed CodingStyle] Signed-off-by: Indika Katugampala Signed-off-by: Douglas Schilling Landgraf Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/CARDLIST.em28xx | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/video4linux/CARDLIST.em28xx b/Documentation/video4linux/CARDLIST.em28xx index 69601089f0a..f97c8533d01 100644 --- a/Documentation/video4linux/CARDLIST.em28xx +++ b/Documentation/video4linux/CARDLIST.em28xx @@ -61,3 +61,4 @@ 62 -> Gadmei TVR200 (em2820/em2840) 63 -> Kaiomy TVnPC U2 (em2860) [eb1a:e303] 64 -> Easy Cap Capture DC-60 (em2860) + 65 -> IO-DATA GV-MVP/SZ (em2820/em2840) [04bb:0515] -- cgit v1.2.3 From 00ec8d0799d56448525b51abbf2075951f637b37 Mon Sep 17 00:00:00 2001 From: Tobias Lorenz Date: Thu, 12 Feb 2009 14:55:45 -0300 Subject: V4L/DVB (10530): Documentation and code cleanups - "DealExtreme" sells the "PCear" radio and that comes from "Sanei Electric". - MPlayer is also usable as radio application. - Consistent usage of tabulators and blanks in the code. Signed-off-by: Tobias Lorenz Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/si470x.txt | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) (limited to 'Documentation') diff --git a/Documentation/video4linux/si470x.txt b/Documentation/video4linux/si470x.txt index 49679e6aaa7..3a7823e01b4 100644 --- a/Documentation/video4linux/si470x.txt +++ b/Documentation/video4linux/si470x.txt @@ -1,6 +1,6 @@ Driver for USB radios for the Silicon Labs Si470x FM Radio Receivers -Copyright (c) 2008 Tobias Lorenz +Copyright (c) 2009 Tobias Lorenz Information from Silicon Labs @@ -41,7 +41,7 @@ chips are known to work: - 10c4:818a: Silicon Labs USB FM Radio Reference Design - 06e1:a155: ADS/Tech FM Radio Receiver (formerly Instant FM Music) (RDX-155-EF) - 1b80:d700: KWorld USB FM Radio SnapMusic Mobile 700 (FM700) -- 10c5:819a: DealExtreme USB Radio +- 10c5:819a: Sanei Electric, Inc. FM USB Radio (sold as DealExtreme.com PCear) Software @@ -52,6 +52,7 @@ Testing is usually done with most application under Debian/testing: - gradio - GTK FM radio tuner - kradio - Comfortable Radio Application for KDE - radio - ncurses-based radio application +- mplayer - The Ultimate Movie Player For Linux There is also a library libv4l, which can be used. It's going to have a function for frequency seeking, either by using hardware functionality as in radio-si470x @@ -69,7 +70,7 @@ Audio Listing USB Audio is provided by the ALSA snd_usb_audio module. It is recommended to also select SND_USB_AUDIO, as this is required to get sound from the radio. For listing you have to redirect the sound, for example using one of the following -commands. +commands. Please adjust the audio devices to your needs (/dev/dsp* and hw:x,x). If you just want to test audio (very poor quality): cat /dev/dsp1 > /dev/dsp @@ -80,6 +81,10 @@ sox -2 --endian little -r 96000 -t oss /dev/dsp1 -t oss /dev/dsp If you use arts try: arecord -D hw:1,0 -r96000 -c2 -f S16_LE | artsdsp aplay -B - +If you use mplayer try: +mplayer -radio adevice=hw=1.0:arate=96000 \ + -rawaudio rate=96000 \ + radio:///capture Module Parameters ================= -- cgit v1.2.3 From 1d6af821a91df15e3fc2720c223ec514ae83dc86 Mon Sep 17 00:00:00 2001 From: Douglas Schilling Landgraf Date: Thu, 12 Feb 2009 14:22:42 -0300 Subject: V4L/DVB (10556): em28xx-cards: Add Pinnacle Dazzle Video Creator Plus DVC107 description Added board Pinnacle Dazzle Video Creator Plus DVC107 to name description field. Signed-off-by: Douglas Schilling Landgraf Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/CARDLIST.em28xx | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/video4linux/CARDLIST.em28xx b/Documentation/video4linux/CARDLIST.em28xx index f97c8533d01..77874bd2055 100644 --- a/Documentation/video4linux/CARDLIST.em28xx +++ b/Documentation/video4linux/CARDLIST.em28xx @@ -7,7 +7,7 @@ 6 -> Terratec Cinergy 200 USB (em2800) 7 -> Leadtek Winfast USB II (em2800) [0413:6023] 8 -> Kworld USB2800 (em2800) - 9 -> Pinnacle Dazzle DVC 90/DVC 100/DVC 101 (em2820/em2840) [2304:0207,2304:021a] + 9 -> Pinnacle Dazzle DVC 90/DVC 100/DVC 101/DVC 107 (em2820/em2840) [2304:0207,2304:021a] 10 -> Hauppauge WinTV HVR 900 (em2880) [2040:6500] 11 -> Terratec Hybrid XS (em2880) [0ccd:0042] 12 -> Kworld PVR TV 2800 RF (em2820/em2840) -- cgit v1.2.3 From 44061c05ac8dedcc45c439e871f654c9521cc726 Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Sat, 14 Feb 2009 07:29:07 -0300 Subject: V4L/DVB (10570): v4l2-framework: documments videobuf usage on drivers Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/v4l2-framework.txt | 92 +++++++++++++++++++++++++++- 1 file changed, 91 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt index 73f9b642392..8d2db7e09e8 100644 --- a/Documentation/video4linux/v4l2-framework.txt +++ b/Documentation/video4linux/v4l2-framework.txt @@ -47,7 +47,9 @@ All drivers have the following structure: 3) Creating V4L2 device nodes (/dev/videoX, /dev/vbiX, /dev/radioX and /dev/vtxX) and keeping track of device-node specific data. -4) Filehandle-specific structs containing per-filehandle data. +4) Filehandle-specific structs containing per-filehandle data; + +5) video buffer handling. This is a rough schematic of how it all relates: @@ -525,3 +527,91 @@ void *video_drvdata(struct file *file); You can go from a video_device struct to the v4l2_device struct using: struct v4l2_device *v4l2_dev = vdev->v4l2_dev; + +video buffer helper functions +----------------------------- + +The v4l2 core API provides a standard method for dealing with video +buffers. Those methods allow a driver to implement read(), mmap() and +overlay() on a consistent way. + +There are currently methods for using video buffers on devices that +supports DMA with scatter/gather method (videobuf-dma-sg), DMA with +linear access (videobuf-dma-contig), and vmalloced buffers, mostly +used on USB drivers (videobuf-vmalloc). + +Any driver using videobuf should provide operations (callbacks) for +four handlers: + +ops->buf_setup - calculates the size of the video buffers and avoid they + to waste more than some maximum limit of RAM; +ops->buf_prepare - fills the video buffer structs and calls + videobuf_iolock() to alloc and prepare mmaped memory; +ops->buf_queue - advices the driver that another buffer were + requested (by read() or by QBUF); +ops->buf_release - frees any buffer that were allocated. + +In order to use it, the driver need to have a code (generally called at +interrupt context) that will properly handle the buffer request lists, +announcing that a new buffer were filled. + +The irq handling code should handle the videobuf task lists, in order +to advice videobuf that a new frame were filled, in order to honor to a +request. The code is generally like this one: + if (list_empty(&dma_q->active)) + return; + + buf = list_entry(dma_q->active.next, struct vbuffer, vb.queue); + + if (!waitqueue_active(&buf->vb.done)) + return; + + /* Some logic to handle the buf may be needed here */ + + list_del(&buf->vb.queue); + do_gettimeofday(&buf->vb.ts); + wake_up(&buf->vb.done); + +Those are the videobuffer functions used on drivers, implemented on +videobuf-core: + +- videobuf_queue_core_init() + Initializes the videobuf infrastructure. This function should be + called before any other videobuf function. + +- videobuf_iolock() + Prepares the videobuf memory for the proper method (read, mmap, overlay). + +- videobuf_queue_is_busy() + Checks if a videobuf is streaming. + +- videobuf_queue_cancel() + Stops video handling. + +- videobuf_mmap_free() + frees mmap buffers. + +- videobuf_stop() + Stops video handling, ends mmap and frees mmap and other buffers. + +- V4L2 api functions. Those functions correspond to VIDIOC_foo ioctls: + videobuf_reqbufs(), videobuf_querybuf(), videobuf_qbuf(), + videobuf_dqbuf(), videobuf_streamon(), videobuf_streamoff(). + +- V4L1 api function (corresponds to VIDIOCMBUF ioctl): + videobuf_cgmbuf() + This function is used to provide backward compatibility with V4L1 + API. + +- Some help functions for read()/poll() operations: + videobuf_read_stream() + For continuous stream read() + videobuf_read_one() + For snapshot read() + videobuf_poll_stream() + polling help function + +The better way to understand it is to take a look at vivi driver. One +of the main reasons for vivi is to be a videobuf usage example. the +vivi_thread_tick() does the task that the IRQ callback would do on PCI +drivers (or the irq callback on USB). -- cgit v1.2.3 From a7a1c0e60c706fc04c42c020cd9c45b8bfe14e8b Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Sat, 14 Feb 2009 07:51:28 -0300 Subject: V4L/DVB (10571): v4l2-framework.txt: Fixes the videobuf init functions Documents the driver usage functions, instead of the generic one used by the videobuf specific handlers. Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/v4l2-framework.txt | 30 +++++++++++++++++++--------- 1 file changed, 21 insertions(+), 9 deletions(-) (limited to 'Documentation') diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt index 8d2db7e09e8..48cdf86248c 100644 --- a/Documentation/video4linux/v4l2-framework.txt +++ b/Documentation/video4linux/v4l2-framework.txt @@ -558,26 +558,38 @@ announcing that a new buffer were filled. The irq handling code should handle the videobuf task lists, in order to advice videobuf that a new frame were filled, in order to honor to a request. The code is generally like this one: - if (list_empty(&dma_q->active)) + if (list_empty(&dma_q->active)) return; - buf = list_entry(dma_q->active.next, struct vbuffer, vb.queue); + buf = list_entry(dma_q->active.next, struct vbuffer, vb.queue); - if (!waitqueue_active(&buf->vb.done)) + if (!waitqueue_active(&buf->vb.done)) return; /* Some logic to handle the buf may be needed here */ - list_del(&buf->vb.queue); - do_gettimeofday(&buf->vb.ts); - wake_up(&buf->vb.done); + list_del(&buf->vb.queue); + do_gettimeofday(&buf->vb.ts); + wake_up(&buf->vb.done); Those are the videobuffer functions used on drivers, implemented on videobuf-core: -- videobuf_queue_core_init() - Initializes the videobuf infrastructure. This function should be - called before any other videobuf function. +- Videobuf init functions + videobuf_queue_sg_init() + Initializes the videobuf infrastructure. This function should be + called before any other videobuf function on drivers that uses DMA + Scatter/Gather buffers. + + videobuf_queue_dma_contig_init + Initializes the videobuf infrastructure. This function should be + called before any other videobuf function on drivers that need DMA + contiguous buffers. + + videobuf_queue_vmalloc_init() + Initializes the videobuf infrastructure. This function should be + called before any other videobuf function on USB (and other drivers) + that need a vmalloced type of videobuf. - videobuf_iolock() Prepares the videobuf memory for the proper method (read, mmap, overlay). -- cgit v1.2.3 From 3a63e4492fbc7aa7f99d4368822da1382ec6fe03 Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Sat, 14 Feb 2009 11:54:23 -0300 Subject: V4L/DVB (10643): v4l2-device: allow a NULL parent device when registering. Some drivers (e.g. for ISA devices) have no parent device because there is no associated bus driver. Allow the parent device to be NULL in those cases when registering v4l2_device. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/v4l2-framework.txt | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) (limited to 'Documentation') diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt index 48cdf86248c..e1620e2a38f 100644 --- a/Documentation/video4linux/v4l2-framework.txt +++ b/Documentation/video4linux/v4l2-framework.txt @@ -84,12 +84,14 @@ You must register the device instance: v4l2_device_register(struct device *dev, struct v4l2_device *v4l2_dev); Registration will initialize the v4l2_device struct and link dev->driver_data -to v4l2_dev. Registration will also set v4l2_dev->name to a value derived from -dev (driver name followed by the bus_id, to be precise). You may change the -name after registration if you want. +to v4l2_dev. If v4l2_dev->name is empty then it will be set to a value derived +from dev (driver name followed by the bus_id, to be precise). If you set it +up before calling v4l2_device_register then it will be untouched. If dev is +NULL, then you *must* setup v4l2_dev->name before calling v4l2_device_register. The first 'dev' argument is normally the struct device pointer of a pci_dev, -usb_device or platform_device. +usb_device or platform_device. It is rare for dev to be NULL, but it happens +with ISA devices, for example. You unregister with: -- cgit v1.2.3 From b01676005446ad51a32bb00577647c7aae7d2624 Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Sat, 14 Feb 2009 12:00:53 -0300 Subject: V4L/DVB (10644): v4l2-subdev: rename dev field to v4l2_dev Remain consistent in the naming: fields pointing to v4l2_device should be called v4l2_dev. There are too many device-like entities without adding to the confusion by mixing naming conventions. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/v4l2-framework.txt | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt index e1620e2a38f..accc376e93c 100644 --- a/Documentation/video4linux/v4l2-framework.txt +++ b/Documentation/video4linux/v4l2-framework.txt @@ -268,7 +268,7 @@ errors (except -ENOIOCTLCMD) occured, then 0 is returned. The second argument to both calls is a group ID. If 0, then all subdevs are called. If non-zero, then only those whose group ID match that value will -be called. Before a bridge driver registers a subdev it can set subdev->grp_id +be called. Before a bridge driver registers a subdev it can set sd->grp_id to whatever value it wants (it's 0 by default). This value is owned by the bridge driver and the sub-device driver will never modify or use it. -- cgit v1.2.3 From cc1139c7cdc1455fdf460c33fe63a36524753834 Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Thu, 26 Feb 2009 23:08:22 -0300 Subject: V4L/DVB(10738a): remove include/linux/video_encoder.h include/linux/video_encoder.h is not used anymore by a v4l driver. Let's remove it and its occurences. Signed-off-by: Mauro Carvalho Chehab --- Documentation/ioctl/ioctl-number.txt | 1 - 1 file changed, 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/ioctl/ioctl-number.txt b/Documentation/ioctl/ioctl-number.txt index f1d63990332..3a311fe952e 100644 --- a/Documentation/ioctl/ioctl-number.txt +++ b/Documentation/ioctl/ioctl-number.txt @@ -125,7 +125,6 @@ Code Seq# Include File Comments 'd' 00-DF linux/video_decoder.h conflict! 'd' F0-FF linux/digi1.h 'e' all linux/digi1.h conflict! -'e' 00-1F linux/video_encoder.h conflict! 'e' 00-1F net/irda/irtty.h conflict! 'f' 00-1F linux/ext2_fs.h 'h' 00-7F Charon filesystem -- cgit v1.2.3 From 812c582390f2c6b81c0400d1286a7bce39d161d0 Mon Sep 17 00:00:00 2001 From: Douglas Schilling Landgraf Date: Wed, 25 Feb 2009 16:52:31 -0300 Subject: V4L/DVB (10739): em28xx-cards: remove incorrect entry Removed EM2821_BOARD_PROLINK_PLAYTV_USB2 entry. This entry has a incorrect tuner set. Signed-off-by: Douglas Schilling Landgraf Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/CARDLIST.em28xx | 1 - 1 file changed, 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/video4linux/CARDLIST.em28xx b/Documentation/video4linux/CARDLIST.em28xx index 77874bd2055..dafbd955ee1 100644 --- a/Documentation/video4linux/CARDLIST.em28xx +++ b/Documentation/video4linux/CARDLIST.em28xx @@ -30,7 +30,6 @@ 30 -> Videology 20K14XUSB USB2.0 (em2820/em2840) 31 -> Usbgear VD204v9 (em2821) 32 -> Supercomp USB 2.0 TV (em2821) - 33 -> SIIG AVTuner-PVR/Prolink PlayTV USB 2.0 (em2821) 34 -> Terratec Cinergy A Hybrid XS (em2860) [0ccd:004f] 35 -> Typhoon DVD Maker (em2860) 36 -> NetGMBH Cam (em2860) -- cgit v1.2.3 From 1f372a930c85270b4435b508b3e029021b1c5b62 Mon Sep 17 00:00:00 2001 From: Douglas Schilling Landgraf Date: Wed, 25 Feb 2009 16:54:31 -0300 Subject: V4L/DVB (10740): em28xx-cards: Add SIIG AVTuner-PVR board Added SIIG AVTuner-PVR to the right entry. Signed-off-by: Douglas Schilling Landgraf Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/CARDLIST.em28xx | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/video4linux/CARDLIST.em28xx b/Documentation/video4linux/CARDLIST.em28xx index dafbd955ee1..5707c6fbf89 100644 --- a/Documentation/video4linux/CARDLIST.em28xx +++ b/Documentation/video4linux/CARDLIST.em28xx @@ -12,7 +12,7 @@ 11 -> Terratec Hybrid XS (em2880) [0ccd:0042] 12 -> Kworld PVR TV 2800 RF (em2820/em2840) 13 -> Terratec Prodigy XS (em2880) [0ccd:0047] - 14 -> Pixelview Prolink PlayTV USB 2.0 (em2820/em2840) + 14 -> SIIG AVTuner-PVR / Pixelview Prolink PlayTV USB 2.0 (em2820/em2840) 15 -> V-Gear PocketTV (em2800) 16 -> Hauppauge WinTV HVR 950 (em2883) [2040:6513,2040:6517,2040:651b] 17 -> Pinnacle PCTV HD Pro Stick (em2880) [2304:0227] -- cgit v1.2.3 From ac40d9e09825c62b77e8b11b3ed201f390550351 Mon Sep 17 00:00:00 2001 From: Douglas Schilling Landgraf Date: Wed, 25 Feb 2009 16:55:48 -0300 Subject: V4L/DVB (10741): em28xx: Add Kaiser Baas Video to DVD maker support Added usb vendor/product id for Kaiser Baas Video to DVD maker. Thanks to Trevor Campbell for providing all data and tests needed to add this card to em28xx driver. Signed-off-by: Douglas Schilling Landgraf Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/CARDLIST.em28xx | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/video4linux/CARDLIST.em28xx b/Documentation/video4linux/CARDLIST.em28xx index 5707c6fbf89..78d0a6eed57 100644 --- a/Documentation/video4linux/CARDLIST.em28xx +++ b/Documentation/video4linux/CARDLIST.em28xx @@ -7,7 +7,7 @@ 6 -> Terratec Cinergy 200 USB (em2800) 7 -> Leadtek Winfast USB II (em2800) [0413:6023] 8 -> Kworld USB2800 (em2800) - 9 -> Pinnacle Dazzle DVC 90/DVC 100/DVC 101/DVC 107 (em2820/em2840) [2304:0207,2304:021a] + 9 -> Pinnacle Dazzle DVC 90/100/101/107 / Kaiser Baas Video to DVD maker (em2820/em2840) [1b80:e302,2304:0207,2304:021a] 10 -> Hauppauge WinTV HVR 900 (em2880) [2040:6500] 11 -> Terratec Hybrid XS (em2880) [0ccd:0042] 12 -> Kworld PVR TV 2800 RF (em2820/em2840) -- cgit v1.2.3 From 5a23b0762c9095e137ce9a559cc7c37b2f8fd083 Mon Sep 17 00:00:00 2001 From: "Igor M. Liplianin" Date: Tue, 3 Mar 2009 12:06:09 -0300 Subject: V4L/DVB (10805): Add support for NetUP Dual DVB-S2 CI card Add support for NetUP Dual DVB-S2 CI card The card based on cx23885 PCI-e bridge, CiMax SP2 Common Interface chips, STM lnbh24 LNB power chip, stv6110 tuners and stv0900 demodulator. http://www.linuxtv.org/wiki/index.php/NetUP_Dual_DVB_S2_CI Signed-off-by: Igor M. Liplianin Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/CARDLIST.cx23885 | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/video4linux/CARDLIST.cx23885 b/Documentation/video4linux/CARDLIST.cx23885 index 5937ff958f0..91aa3c0f0dd 100644 --- a/Documentation/video4linux/CARDLIST.cx23885 +++ b/Documentation/video4linux/CARDLIST.cx23885 @@ -15,3 +15,4 @@ 14 -> TurboSight TBS 6920 [6920:8888] 15 -> TeVii S470 [d470:9022] 16 -> DVBWorld DVB-S2 2005 [0001:2005] + 17 -> NetUP Dual DVB-S2 CI [1b55:2a2c] -- cgit v1.2.3 From 0c5db425519487d06a5a14eb369268f4a2b32677 Mon Sep 17 00:00:00 2001 From: Bruno Christo Date: Mon, 2 Mar 2009 22:38:59 -0300 Subject: V4L/DVB (10827): Add support for GeoVision GV-800(S) I have a GeoVision GV-800(S) card, it has 4 CONEXANT BT878A chips. It has 16 video inputs and 4 audio inputs, and it is almost identical to the GV-800, as seen on http://bttv-gallery.de . The only difference appears to be the analog mux, it has a CD22M3494 in place of the MT8816AP. The card has a blue PCB, as seen in this picture: http://www.gsbr.com.br/imagem/kits/GeoVision%20GV%20800.jpg . This card wasn't originally supported, and it was detected as UNKNOWN/GENERIC. The video inputs weren't working, so I tried "forcing" a few cards like the GeoVision GV-600, but there was still no video. So I made a patch to support this card, based on the Kodicom 4400r. The GV-800(S) is identified as follows: ... 02:00.0 Multimedia video controller: Brooktree Corporation Bt878 Video Capture (rev 11) 02:00.1 Multimedia controller: Brooktree Corporation Bt878 Audio Capture (rev 11) 02:04.0 Multimedia video controller: Brooktree Corporation Bt878 Video Capture (rev 11) 02:04.1 Multimedia controller: Brooktree Corporation Bt878 Audio Capture (rev 11) 02:08.0 Multimedia video controller: Brooktree Corporation Bt878 Video Capture (rev 11) 02:08.1 Multimedia controller: Brooktree Corporation Bt878 Audio Capture (rev 11) 02:0c.0 Multimedia video controller: Brooktree Corporation Bt878 Video Capture (rev 11) 02:0c.1 Multimedia controller: Brooktree Corporation Bt878 Audio Capture (rev 11) ... 02:00.0 0400: 109e:036e (rev 11) Subsystem: 800a:763d Flags: bus master, medium devsel, latency 32, IRQ 10 Memory at cdfff000 (32-bit, prefetchable) [size=4K] Capabilities: [44] Vital Product Data Capabilities: [4c] Power Management version 2 Kernel modules: bttv 02:00.1 0480: 109e:0878 (rev 11) Subsystem: 800a:763d Flags: bus master, medium devsel, latency 32, IRQ 10 Memory at cdffe000 (32-bit, prefetchable) [size=4K] Capabilities: [44] Vital Product Data Capabilities: [4c] Power Management version 2 02:04.0 0400: 109e:036e (rev 11) Subsystem: 800b:763d Flags: bus master, medium devsel, latency 32, IRQ 10 Memory at cdffd000 (32-bit, prefetchable) [size=4K] Capabilities: [44] Vital Product Data Capabilities: [4c] Power Management version 2 Kernel modules: bttv 02:04.1 0480: 109e:0878 (rev 11) Subsystem: 800b:763d Flags: bus master, medium devsel, latency 32, IRQ 10 Memory at cdffc000 (32-bit, prefetchable) [size=4K] Capabilities: [44] Vital Product Data Capabilities: [4c] Power Management version 2 02:08.0 0400: 109e:036e (rev 11) Subsystem: 800c:763d Flags: bus master, medium devsel, latency 32, IRQ 10 Memory at cdffb000 (32-bit, prefetchable) [size=4K] Capabilities: [44] Vital Product Data Capabilities: [4c] Power Management version 2 Kernel modules: bttv 02:08.1 0480: 109e:0878 (rev 11) Subsystem: 800c:763d Flags: bus master, medium devsel, latency 32, IRQ 10 Memory at cdffa000 (32-bit, prefetchable) [size=4K] Capabilities: [44] Vital Product Data Capabilities: [4c] Power Management version 2 02:0c.0 0400: 109e:036e (rev 11) Subsystem: 800d:763d Flags: bus master, medium devsel, latency 32, IRQ 10 Memory at cdff9000 (32-bit, prefetchable) [size=4K] Capabilities: [44] Vital Product Data Capabilities: [4c] Power Management version 2 Kernel modules: bttv 02:0c.1 0480: 109e:0878 (rev 11) Subsystem: 800d:763d Flags: bus master, medium devsel, latency 32, IRQ 10 Memory at cdff8000 (32-bit, prefetchable) [size=4K] Capabilities: [44] Vital Product Data Capabilities: [4c] Power Management version 2 As you can see, the GV-800(S) card is almost identical to the GV-800 on bttv-gallery, so this patch might also work for that card. If not, only a few changes should be required on the gv800s_write() function. After this patch, the video inputs work correctly on linux 2.6.24 and 2.6.27 using the software 'motion'. The input order may seem a little odd, but it's the order the original software/driver uses, and I decided to keep that order to get the most out of the card. I tried to get the audio working with the snd-bt87x module, but I only get noise from every audio input, even after selecting a different mux with alsamixer. Also, after trying to play sound from those sources, I randomly get a RISC error about an invalid RISC opcode, and then that output stops working. I also can't change the sampling rate when recording. Any pointers to adding audio support are welcome. Signed-off-by: Bruno Christo Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/CARDLIST.bttv | 2 ++ 1 file changed, 2 insertions(+) (limited to 'Documentation') diff --git a/Documentation/video4linux/CARDLIST.bttv b/Documentation/video4linux/CARDLIST.bttv index 4dfe6264137..1da2c62715a 100644 --- a/Documentation/video4linux/CARDLIST.bttv +++ b/Documentation/video4linux/CARDLIST.bttv @@ -155,3 +155,5 @@ 154 -> PHYTEC VD-012-X1 (bt878) 155 -> PHYTEC VD-012-X2 (bt878) 156 -> IVCE-8784 [0000:f050,0001:f050,0002:f050,0003:f050] +157 -> Geovision GV-800(S) (master) [800a:763d] +158 -> Geovision GV-800(S) (slave) [800b:763d,800c:763d,800d:763d] -- cgit v1.2.3 From f9996c95623d63de6f5957512976137bbac729f0 Mon Sep 17 00:00:00 2001 From: Michael Krufky Date: Sat, 28 Feb 2009 17:45:17 -0300 Subject: V4L/DVB (10877): saa7134: add analog support for Hauppauge HVR1110r3 boards Signed-off-by: Michael Krufky Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/CARDLIST.saa7134 | 2 ++ 1 file changed, 2 insertions(+) (limited to 'Documentation') diff --git a/Documentation/video4linux/CARDLIST.saa7134 b/Documentation/video4linux/CARDLIST.saa7134 index b8d470596b0..325c69fe91f 100644 --- a/Documentation/video4linux/CARDLIST.saa7134 +++ b/Documentation/video4linux/CARDLIST.saa7134 @@ -153,3 +153,5 @@ 152 -> Asus Tiger Rev:1.00 [1043:4857] 153 -> Kworld Plus TV Analog Lite PCI [17de:7128] 154 -> Avermedia AVerTV GO 007 FM Plus [1461:f31d] +155 -> Hauppauge WinTV-HVR1150 [0070:6706,0070:6708] +156 -> Hauppauge WinTV-HVR1110r3 [0070:6707,0070:6709,0070:670a] -- cgit v1.2.3 From 42d12f5aa105af08bc0ed0580e32156a1a325c6b Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Tue, 10 Mar 2009 05:02:28 -0300 Subject: V4L/DVB (10870a): remove all references for video_decoder.h changeset 04934e44e3784a1b969582e2d59afcec278470c6 removed the last implementation that were still using the V4L1 obsoleted header. Now, video_decoder.h is not used anymore by any driver. Let's remove it and all references for it in Kernel. Signed-off-by: Mauro Carvalho Chehab --- Documentation/feature-removal-schedule.txt | 8 ++++---- Documentation/ioctl/ioctl-number.txt | 1 - 2 files changed, 4 insertions(+), 5 deletions(-) (limited to 'Documentation') diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 1135996bec8..5e02b83ac12 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -64,10 +64,10 @@ Who: Pavel Machek --------------------------- -What: Video4Linux API 1 ioctls and video_decoder.h from Video devices. -When: December 2008 -Files: include/linux/video_decoder.h include/linux/videodev.h -Check: include/linux/video_decoder.h include/linux/videodev.h +What: Video4Linux API 1 ioctls and from Video devices. +When: July 2009 +Files: include/linux/videodev.h +Check: include/linux/videodev.h Why: V4L1 AP1 was replaced by V4L2 API during migration from 2.4 to 2.6 series. The old API have lots of drawbacks and don't provide enough means to work with all video and audio standards. The newer API is diff --git a/Documentation/ioctl/ioctl-number.txt b/Documentation/ioctl/ioctl-number.txt index 3a311fe952e..1f779a25c70 100644 --- a/Documentation/ioctl/ioctl-number.txt +++ b/Documentation/ioctl/ioctl-number.txt @@ -122,7 +122,6 @@ Code Seq# Include File Comments 'c' 00-7F linux/coda.h conflict! 'c' 80-9F arch/s390/include/asm/chsc.h 'd' 00-FF linux/char/drm/drm/h conflict! -'d' 00-DF linux/video_decoder.h conflict! 'd' F0-FF linux/digi1.h 'e' all linux/digi1.h conflict! 'e' 00-1F net/irda/irtty.h conflict! -- cgit v1.2.3 From cf5193c74009e33428daefbf74f4770733c8ee36 Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Fri, 6 Mar 2009 09:29:09 -0300 Subject: V4L/DVB (10909): tvmixer: remove last remaining references to this deleted module. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/bttv/Insmod-options | 10 ---------- 1 file changed, 10 deletions(-) (limited to 'Documentation') diff --git a/Documentation/video4linux/bttv/Insmod-options b/Documentation/video4linux/bttv/Insmod-options index 5ef75787f83..bbe3ed667d9 100644 --- a/Documentation/video4linux/bttv/Insmod-options +++ b/Documentation/video4linux/bttv/Insmod-options @@ -81,16 +81,6 @@ tuner.o pal=[bdgil] select PAL variant (used for some tuners only, important for the audio carrier). -tvmixer.o - registers a mixer device for the TV card's volume/bass/treble - controls (requires a i2c audio control chip like the msp3400). - - insmod args: - debug=1 print some debug info to the syslog. - devnr=n allocate device #n (0 == /dev/mixer, - 1 = /dev/mixer1, ...), default is to - use the first free one. - tvaudio.o new, experimental module which is supported to provide a single driver for all simple i2c audio control chips (tda/tea*). -- cgit v1.2.3 From e8944282a76f94bcf84ae3b7a91328bd03835ea1 Mon Sep 17 00:00:00 2001 From: Michael Krufky Date: Tue, 10 Mar 2009 17:02:07 -0300 Subject: V4L/DVB (10923): saa7134: fix typo in product name replace occurances of "HVR1150" with "HVR1120" - this was a typo. Signed-off-by: Michael Krufky Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/CARDLIST.saa7134 | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/video4linux/CARDLIST.saa7134 b/Documentation/video4linux/CARDLIST.saa7134 index 325c69fe91f..626820e519e 100644 --- a/Documentation/video4linux/CARDLIST.saa7134 +++ b/Documentation/video4linux/CARDLIST.saa7134 @@ -153,5 +153,5 @@ 152 -> Asus Tiger Rev:1.00 [1043:4857] 153 -> Kworld Plus TV Analog Lite PCI [17de:7128] 154 -> Avermedia AVerTV GO 007 FM Plus [1461:f31d] -155 -> Hauppauge WinTV-HVR1150 [0070:6706,0070:6708] +155 -> Hauppauge WinTV-HVR1120 [0070:6706,0070:6708] 156 -> Hauppauge WinTV-HVR1110r3 [0070:6707,0070:6709,0070:670a] -- cgit v1.2.3 From 3abdedd8a4e3b1a0ad164c67929b3e798c85cd11 Mon Sep 17 00:00:00 2001 From: Michael Krufky Date: Mon, 19 Jan 2009 01:10:49 -0300 Subject: V4L/DVB (10926): saa7134: enable digital tv support for Hauppauge WinTV-HVR1120 Signed-off-by: Michael Krufky Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/CARDLIST.saa7134 | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/video4linux/CARDLIST.saa7134 b/Documentation/video4linux/CARDLIST.saa7134 index 626820e519e..6dacf282525 100644 --- a/Documentation/video4linux/CARDLIST.saa7134 +++ b/Documentation/video4linux/CARDLIST.saa7134 @@ -153,5 +153,5 @@ 152 -> Asus Tiger Rev:1.00 [1043:4857] 153 -> Kworld Plus TV Analog Lite PCI [17de:7128] 154 -> Avermedia AVerTV GO 007 FM Plus [1461:f31d] -155 -> Hauppauge WinTV-HVR1120 [0070:6706,0070:6708] +155 -> Hauppauge WinTV-HVR1120 ATSC/QAM-Hybrid [0070:6706,0070:6708] 156 -> Hauppauge WinTV-HVR1110r3 [0070:6707,0070:6709,0070:670a] -- cgit v1.2.3 From 4dbf46a0485a5b0704e1c4b55a173128fbaedec9 Mon Sep 17 00:00:00 2001 From: Jean Delvare Date: Tue, 10 Mar 2009 23:28:17 -0300 Subject: V4L/DVB (10931): zoran: Drop the lock_norm module parameter The lock_norm module parameter doesn't look terribly useful. If you don't want to change the norm, just don't change it. As a matter of fact, no other v4l driver has such a parameter. Cc: Hans Verkuil Signed-off-by: Jean Delvare Signed-off-by: Trent Piepho Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/Zoran | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'Documentation') diff --git a/Documentation/video4linux/Zoran b/Documentation/video4linux/Zoran index 295462b2317..0e89e767629 100644 --- a/Documentation/video4linux/Zoran +++ b/Documentation/video4linux/Zoran @@ -401,8 +401,7 @@ Additional notes for software developers: first set the correct norm. Well, it seems logically correct: TV standard is "more constant" for current country than geometry settings of a variety of TV capture cards which may work in ITU or - square pixel format. Remember that users now can lock the norm to - avoid any ambiguity. + square pixel format. -- Please note that lavplay/lavrec are also included in the MJPEG-tools (http://mjpeg.sf.net/). -- cgit v1.2.3 From 76ecf4599e55fd16bdb333a737c6243105c916e6 Mon Sep 17 00:00:00 2001 From: Robert Millan Date: Wed, 11 Mar 2009 08:18:53 -0300 Subject: V4L/DVB (10944): Conceptronic CTVFMI2 PCI Id My BTTV_BOARD_CONCEPTRONIC_CTVFMI2 card wasn't auto-detected, here's a patch that adds its PCI id. lspci -nnv output: 05:06.0 Multimedia video controller [0400]: Brooktree Corporation Bt878 Video Capture [109e:036e] (rev 11) 05:06.1 Multimedia controller [0480]: Brooktree Corporation Bt878 Audio Capture [109e:0878] (rev 11) Press within 3 seconds if this is wrong. Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/CARDLIST.bttv | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/video4linux/CARDLIST.bttv b/Documentation/video4linux/CARDLIST.bttv index 1da2c62715a..e17750473e0 100644 --- a/Documentation/video4linux/CARDLIST.bttv +++ b/Documentation/video4linux/CARDLIST.bttv @@ -135,7 +135,7 @@ 134 -> Adlink RTV24 135 -> DViCO FusionHDTV 5 Lite [18ac:d500] 136 -> Acorp Y878F [9511:1540] -137 -> Conceptronic CTVFMi v2 +137 -> Conceptronic CTVFMi v2 [036e:109e] 138 -> Prolink Pixelview PV-BT878P+ (Rev.2E) 139 -> Prolink PixelView PlayTV MPEG2 PV-M4900 140 -> Osprey 440 [0070:ff07] -- cgit v1.2.3 From 70101a2785598f1a743c1e0fb65264c55bf5a29f Mon Sep 17 00:00:00 2001 From: Stephan Wienczny Date: Tue, 10 Mar 2009 19:08:06 -0300 Subject: V4L/DVB (10949): Add support for Terratec Cinergy HT PCI MKII This patch adds support for Terratec Cinergy HT PCI MKII with card id 79. Its more or less a copy of Pinnacle Hybrid PCTV. Thanks to k1ngf1sher on forum.ubuntuusers.de for the idea to copy that card. Signed-off-by: Stephan Wienczny Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/CARDLIST.cx88 | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/video4linux/CARDLIST.cx88 b/Documentation/video4linux/CARDLIST.cx88 index 0d08f1edcf6..71e9db0b26f 100644 --- a/Documentation/video4linux/CARDLIST.cx88 +++ b/Documentation/video4linux/CARDLIST.cx88 @@ -77,3 +77,4 @@ 76 -> SATTRADE ST4200 DVB-S/S2 [b200:4200] 77 -> TBS 8910 DVB-S [8910:8888] 78 -> Prof 6200 DVB-S [b022:3022] + 79 -> Terratec Cinergy HT PCI MKII [153b:1177] -- cgit v1.2.3 From 2c79252326421dd49c059aceec0880d2cf15b17a Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Thu, 12 Mar 2009 18:34:19 -0300 Subject: V4L/DVB (10980): doc: improve the v4l2-framework documentation. Emphasize the need to call i2c_set_adapdata and clarify the use of the chipid in v4l2_i2c_new_(probed_)device(). Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/v4l2-framework.txt | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) (limited to 'Documentation') diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt index accc376e93c..51a7b6db118 100644 --- a/Documentation/video4linux/v4l2-framework.txt +++ b/Documentation/video4linux/v4l2-framework.txt @@ -359,8 +359,8 @@ This loads the given module (can be NULL if no module needs to be loaded) and calls i2c_new_device() with the given i2c_adapter and chip/address arguments. If all goes well, then it registers the subdev with the v4l2_device. It gets the v4l2_device by calling i2c_get_adapdata(adapter), so you should make sure -that adapdata is set to v4l2_device when you setup the i2c_adapter in your -driver. +to call i2c_set_adapdata(adapter, v4l2_device) when you setup the i2c_adapter +in your driver. You can also use v4l2_i2c_new_probed_subdev() which is very similar to v4l2_i2c_new_subdev(), except that it has an array of possible I2C addresses @@ -368,6 +368,14 @@ that it should probe. Internally it calls i2c_new_probed_device(). Both functions return NULL if something went wrong. +Note that the chipid you pass to v4l2_i2c_new_(probed_)subdev() is usually +the same as the module name. It allows you to specify a chip variant, e.g. +"saa7114" or "saa7115". In general though the i2c driver autodetects this. +The use of chipid is something that needs to be looked at more closely at a +later date. It differs between i2c drivers and as such can be confusing. +To see which chip variants are supported you can look in the i2c driver code +for the i2c_device_id table. This lists all the possibilities. + struct video_device ------------------- -- cgit v1.2.3 From 005759613b95264fba9138010f112bc138c857c2 Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Fri, 13 Mar 2009 10:03:04 -0300 Subject: V4L/DVB (10988): v4l2-dev: use parent field if the v4l2_device has no parent set. Normally the parent device of v4l2_device is used as the video device node's parent. But if it was not set, then use the parent field in the video_device struct. This is needed in the cx88 driver, which has one core v4l2_device but creates multiple pci devices (one each for raw and mpeg video). So you cannot associate the core v4l2_device with a particular PCI device, but you can do that for each video_device. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/v4l2-framework.txt | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt index 51a7b6db118..df0247ed13d 100644 --- a/Documentation/video4linux/v4l2-framework.txt +++ b/Documentation/video4linux/v4l2-framework.txt @@ -91,7 +91,8 @@ NULL, then you *must* setup v4l2_dev->name before calling v4l2_device_register. The first 'dev' argument is normally the struct device pointer of a pci_dev, usb_device or platform_device. It is rare for dev to be NULL, but it happens -with ISA devices, for example. +with ISA devices or when one device creates multiple PCI devices, thus making +it impossible to associate v4l2_dev with a particular parent. You unregister with: @@ -414,6 +415,15 @@ You should also set these fields: - ioctl_ops: if you use the v4l2_ioctl_ops to simplify ioctl maintenance (highly recommended to use this and it might become compulsory in the future!), then set this to your v4l2_ioctl_ops struct. +- parent: you only set this if v4l2_device was registered with NULL as + the parent device struct. This only happens in cases where one hardware + device has multiple PCI devices that all share the same v4l2_device core. + + The cx88 driver is an example of this: one core v4l2_device struct, but + it is used by both an raw video PCI device (cx8800) and a MPEG PCI device + (cx8802). Since the v4l2_device cannot be associated with a particular + PCI device it is setup without a parent device. But when the struct + video_device is setup you do know which parent PCI device to use. If you use v4l2_ioctl_ops, then you should set either .unlocked_ioctl or .ioctl to video_ioctl2 in your v4l2_file_operations struct. -- cgit v1.2.3 From 98ec633972a70cf71d71bc8762804f0af4792d08 Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Sun, 8 Mar 2009 17:02:10 -0300 Subject: V4L/DVB (11021): v4l2-device: add a notify callback. Add a notify callback to v4l2_device to let sub-devices notify their parent of special events. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/v4l2-framework.txt | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'Documentation') diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt index df0247ed13d..4207590b2ac 100644 --- a/Documentation/video4linux/v4l2-framework.txt +++ b/Documentation/video4linux/v4l2-framework.txt @@ -94,6 +94,11 @@ usb_device or platform_device. It is rare for dev to be NULL, but it happens with ISA devices or when one device creates multiple PCI devices, thus making it impossible to associate v4l2_dev with a particular parent. +You can also supply a notify() callback that can be called by sub-devices to +notify you of events. Whether you need to set this depends on the sub-device. +Any notifications a sub-device supports must be defined in a header in +include/media/.h. + You unregister with: v4l2_device_unregister(struct v4l2_device *v4l2_dev); @@ -281,6 +286,11 @@ e.g. AUDIO_CONTROLLER and specify that as the group ID value when calling v4l2_device_call_all(). That ensures that it will only go to the subdev that needs it. +If the sub-device needs to notify its v4l2_device parent of an event, then +it can call v4l2_subdev_notify(sd, notification, arg). This macro checks +whether there is a notify() callback defined and returns -ENODEV if not. +Otherwise the result of the notify() call is returned. + The advantage of using v4l2_subdev is that it is a generic struct and does not contain any knowledge about the underlying hardware. So a driver might contain several subdevs that use an I2C bus, but also a subdev that is -- cgit v1.2.3 From 71cb2764fcc51bd9e1b95be5b0f2da6f026634c7 Mon Sep 17 00:00:00 2001 From: Jean-Francois Moine Date: Tue, 3 Mar 2009 05:33:41 -0300 Subject: V4L/DVB (11039): gspca - most jpeg subdrivers: Change the JPEG header creation. Signed-off-by: Jean-Francois Moine Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/CARDLIST.bttv | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/video4linux/CARDLIST.bttv b/Documentation/video4linux/CARDLIST.bttv index e17750473e0..f11c583295e 100644 --- a/Documentation/video4linux/CARDLIST.bttv +++ b/Documentation/video4linux/CARDLIST.bttv @@ -157,3 +157,4 @@ 156 -> IVCE-8784 [0000:f050,0001:f050,0002:f050,0003:f050] 157 -> Geovision GV-800(S) (master) [800a:763d] 158 -> Geovision GV-800(S) (slave) [800b:763d,800c:763d,800d:763d] +159 -> ProVideo PV183 [1830:1540,1831:1540,1832:1540,1833:1540,1834:1540,1835:1540,1836:1540,1837:1540] -- cgit v1.2.3 From ae6cfaace120f4330715b56265ce0e4a710e1276 Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Sat, 14 Mar 2009 08:28:45 -0300 Subject: V4L/DVB (11044): v4l2-device: add v4l2_device_disconnect Call v4l2_device_disconnect when the parent of a hotpluggable device disconnects. This ensures that you do not have a pointer to a device that is no longer present. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/CARDLIST.bttv | 1 - Documentation/video4linux/v4l2-framework.txt | 11 +++++++++++ 2 files changed, 11 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/video4linux/CARDLIST.bttv b/Documentation/video4linux/CARDLIST.bttv index f11c583295e..e17750473e0 100644 --- a/Documentation/video4linux/CARDLIST.bttv +++ b/Documentation/video4linux/CARDLIST.bttv @@ -157,4 +157,3 @@ 156 -> IVCE-8784 [0000:f050,0001:f050,0002:f050,0003:f050] 157 -> Geovision GV-800(S) (master) [800a:763d] 158 -> Geovision GV-800(S) (slave) [800b:763d,800c:763d,800d:763d] -159 -> ProVideo PV183 [1830:1540,1831:1540,1832:1540,1833:1540,1834:1540,1835:1540,1836:1540,1837:1540] diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt index 4207590b2ac..a31177390e5 100644 --- a/Documentation/video4linux/v4l2-framework.txt +++ b/Documentation/video4linux/v4l2-framework.txt @@ -105,6 +105,17 @@ You unregister with: Unregistering will also automatically unregister all subdevs from the device. +If you have a hotpluggable device (e.g. a USB device), then when a disconnect +happens the parent device becomes invalid. Since v4l2_device has a pointer to +that parent device it has to be cleared as well to mark that the parent is +gone. To do this call: + + v4l2_device_disconnect(struct v4l2_device *v4l2_dev); + +This does *not* unregister the subdevs, so you still need to call the +v4l2_device_unregister() function for that. If your driver is not hotpluggable, +then there is no need to call v4l2_device_disconnect(). + Sometimes you need to iterate over all devices registered by a specific driver. This is usually the case if multiple device drivers use the same hardware. E.g. the ivtvfb driver is a framebuffer driver that uses the ivtv -- cgit v1.2.3 From 15965f063d6d42bd451415923c4cccbdb4a61bdd Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Sat, 14 Mar 2009 15:06:08 -0300 Subject: V4L/DVB (11051): v4l-dvb: replace remaining references to the old mailinglist. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/bttv/README | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'Documentation') diff --git a/Documentation/video4linux/bttv/README b/Documentation/video4linux/bttv/README index 7ca2154c2bf..3a367cdb664 100644 --- a/Documentation/video4linux/bttv/README +++ b/Documentation/video4linux/bttv/README @@ -63,8 +63,8 @@ If you have some knowledge and spare time, please try to fix this yourself (patches very welcome of course...) You know: The linux slogan is "Do it yourself". -There is a mailing list: video4linux-list@redhat.com. -https://listman.redhat.com/mailman/listinfo/video4linux-list +There is a mailing list: linux-media@vger.kernel.org +http://vger.kernel.org/vger-lists.html#linux-media If you have trouble with some specific TV card, try to ask there instead of mailing me directly. The chance that someone with the -- cgit v1.2.3 From 06e9509ff3484578c111bbc6f9e0e97c086a1131 Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Thu, 19 Mar 2009 12:10:00 -0300 Subject: V4L/DVB (11108): get_dvb_firmware: Add option to download firmware for cx231xx Signed-off-by: Mauro Carvalho Chehab --- Documentation/dvb/get_dvb_firmware | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/dvb/get_dvb_firmware b/Documentation/dvb/get_dvb_firmware index f2e908d7f90..72455b6d900 100644 --- a/Documentation/dvb/get_dvb_firmware +++ b/Documentation/dvb/get_dvb_firmware @@ -25,7 +25,7 @@ use IO::Handle; "tda10046lifeview", "av7110", "dec2000t", "dec2540t", "dec3000s", "vp7041", "dibusb", "nxt2002", "nxt2004", "or51211", "or51132_qam", "or51132_vsb", "bluebird", - "opera1"); + "opera1", "cx231xx"); # Check args syntax() if (scalar(@ARGV) != 1); @@ -345,6 +345,19 @@ sub or51211 { $fwfile; } +sub cx231xx { + my $fwfile = "v4l-cx231xx-avcore-01.fw"; + my $url = "http://linuxtv.org/downloads/firmware/$fwfile"; + my $hash = "7d3bb956dc9df0eafded2b56ba57cc42"; + + checkstandard(); + + wgetfile($fwfile, $url); + verify($fwfile, $hash); + + $fwfile; +} + sub or51132_qam { my $fwfile = "dvb-fe-or51132-qam.fw"; my $url = "http://linuxtv.org/downloads/firmware/$fwfile"; -- cgit v1.2.3 From dceaddb978a7fcd2efbdf6775a509529757327c3 Mon Sep 17 00:00:00 2001 From: Alan McIvor Date: Thu, 12 Mar 2009 21:43:34 -0300 Subject: V4L/DVB (11124): Add support for ProVideo PV-183 to bttv Add support for ProVideo PV-183 to bttv This patch adds support for the ProVideo PV-183 card to the bttv device driver. The PV-183 is a PCI card with 8 BT878 devices plus a Hint Corp HiNT HB4 PCI-PCI Bridge. Each BT878 has two composite input channels available. There are no tuners on this card. Signed-off-by: Alan McIvor Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/CARDLIST.bttv | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/video4linux/CARDLIST.bttv b/Documentation/video4linux/CARDLIST.bttv index e17750473e0..f11c583295e 100644 --- a/Documentation/video4linux/CARDLIST.bttv +++ b/Documentation/video4linux/CARDLIST.bttv @@ -157,3 +157,4 @@ 156 -> IVCE-8784 [0000:f050,0001:f050,0002:f050,0003:f050] 157 -> Geovision GV-800(S) (master) [800a:763d] 158 -> Geovision GV-800(S) (slave) [800b:763d,800c:763d,800d:763d] +159 -> ProVideo PV183 [1830:1540,1831:1540,1832:1540,1833:1540,1834:1540,1835:1540,1836:1540,1837:1540] -- cgit v1.2.3 From b888c5dadb4ae409964bd7b9bedfac507ab10972 Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Mon, 23 Mar 2009 10:57:15 -0300 Subject: V4L/DVB (11136): get_dvb_firmware: Add download code for cx18 firmwares Signed-off-by: Mauro Carvalho Chehab --- Documentation/dvb/get_dvb_firmware | 29 ++++++++++++++++++++++++++--- 1 file changed, 26 insertions(+), 3 deletions(-) (limited to 'Documentation') diff --git a/Documentation/dvb/get_dvb_firmware b/Documentation/dvb/get_dvb_firmware index 72455b6d900..2d32590a1f6 100644 --- a/Documentation/dvb/get_dvb_firmware +++ b/Documentation/dvb/get_dvb_firmware @@ -25,7 +25,7 @@ use IO::Handle; "tda10046lifeview", "av7110", "dec2000t", "dec2540t", "dec3000s", "vp7041", "dibusb", "nxt2002", "nxt2004", "or51211", "or51132_qam", "or51132_vsb", "bluebird", - "opera1", "cx231xx"); + "opera1", "cx231xx", "cx18", "cx23885" ); # Check args syntax() if (scalar(@ARGV) != 1); @@ -37,8 +37,8 @@ for ($i=0; $i < scalar(@components); $i++) { $outfile = eval($cid); die $@ if $@; print STDERR < '588f081b562f5c653a3db1ad8f65939a', + 'v4l-cx23418-cpu.fw' => 'b6c7ed64bc44b1a6e0840adaeac39d79', + 'v4l-cx23418-dig.fw' => '95bc688d3e7599fd5800161e9971cc55', + ); + + checkstandard(); + + my $allfiles; + foreach my $fwfile (keys %files) { + wgetfile($fwfile, "$url/$fwfile"); + verify($fwfile, $files{$fwfile}); + $allfiles .= " $fwfile"; + } + + $allfiles =~ s/^\s//; + + $allfiles; +} + sub or51132_qam { my $fwfile = "dvb-fe-or51132-qam.fw"; my $url = "http://linuxtv.org/downloads/firmware/$fwfile"; -- cgit v1.2.3 From 5297e6f7e9818a43228f6b4131c4630f08075093 Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Mon, 23 Mar 2009 11:46:19 -0300 Subject: V4L/DVB (11137): get_dvb_firmware: add cx23885 firmwares Signed-off-by: Mauro Carvalho Chehab --- Documentation/dvb/get_dvb_firmware | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) (limited to 'Documentation') diff --git a/Documentation/dvb/get_dvb_firmware b/Documentation/dvb/get_dvb_firmware index 2d32590a1f6..7e485eabda7 100644 --- a/Documentation/dvb/get_dvb_firmware +++ b/Documentation/dvb/get_dvb_firmware @@ -381,6 +381,29 @@ sub cx18 { $allfiles; } +sub cx23885 { + my $url = "http://linuxtv.org/downloads/firmware/"; + + my %files = ( + 'v4l-cx23885-avcore-01.fw' => 'a9f8f5d901a7fb42f552e1ee6384f3bb', + 'v4l-cx23885-enc.fw' => 'a9f8f5d901a7fb42f552e1ee6384f3bb', + 'v4l-cx25840.fw' => 'dadb79e9904fc8af96e8111d9cb59320', + ); + + checkstandard(); + + my $allfiles; + foreach my $fwfile (keys %files) { + wgetfile($fwfile, "$url/$fwfile"); + verify($fwfile, $files{$fwfile}); + $allfiles .= " $fwfile"; + } + + $allfiles =~ s/^\s//; + + $allfiles; +} + sub or51132_qam { my $fwfile = "dvb-fe-or51132-qam.fw"; my $url = "http://linuxtv.org/downloads/firmware/$fwfile"; -- cgit v1.2.3 From f65a95bbf4f23dd83596e7c2dd78f4e1cc268c4f Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Mon, 23 Mar 2009 12:35:03 -0300 Subject: V4L/DVB (11138): get_dvb_firmware: add support for downloading the cx2584x firmware for pvrusb2 Signed-off-by: Mauro Carvalho Chehab --- Documentation/dvb/get_dvb_firmware | 22 +++++++++++++++++++++- 1 file changed, 21 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/dvb/get_dvb_firmware b/Documentation/dvb/get_dvb_firmware index 7e485eabda7..2f21ecd4c20 100644 --- a/Documentation/dvb/get_dvb_firmware +++ b/Documentation/dvb/get_dvb_firmware @@ -25,7 +25,7 @@ use IO::Handle; "tda10046lifeview", "av7110", "dec2000t", "dec2540t", "dec3000s", "vp7041", "dibusb", "nxt2002", "nxt2004", "or51211", "or51132_qam", "or51132_vsb", "bluebird", - "opera1", "cx231xx", "cx18", "cx23885" ); + "opera1", "cx231xx", "cx18", "cx23885", "pvrusb2" ); # Check args syntax() if (scalar(@ARGV) != 1); @@ -387,6 +387,26 @@ sub cx23885 { my %files = ( 'v4l-cx23885-avcore-01.fw' => 'a9f8f5d901a7fb42f552e1ee6384f3bb', 'v4l-cx23885-enc.fw' => 'a9f8f5d901a7fb42f552e1ee6384f3bb', + ); + + checkstandard(); + + my $allfiles; + foreach my $fwfile (keys %files) { + wgetfile($fwfile, "$url/$fwfile"); + verify($fwfile, $files{$fwfile}); + $allfiles .= " $fwfile"; + } + + $allfiles =~ s/^\s//; + + $allfiles; +} + +sub pvrusb2 { + my $url = "http://linuxtv.org/downloads/firmware/"; + + my %files = ( 'v4l-cx25840.fw' => 'dadb79e9904fc8af96e8111d9cb59320', ); -- cgit v1.2.3 From 7ddfda9aa6a735c2b883b8cf677099bce27bf708 Mon Sep 17 00:00:00 2001 From: Jean-Francois Moine Date: Thu, 26 Mar 2009 05:13:40 -0300 Subject: V4L/DVB (11223): gspca - doc: Add the 15b8:6001 webcam to the Documentation. Signed-off-by: Jean-Francois Moine Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/gspca.txt | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/video4linux/gspca.txt b/Documentation/video4linux/gspca.txt index 12c8ff7058b..98529e03a46 100644 --- a/Documentation/video4linux/gspca.txt +++ b/Documentation/video4linux/gspca.txt @@ -282,6 +282,7 @@ spca561 10fd:7e50 FlyCam Usb 100 zc3xx 10fd:8050 Typhoon Webshot II USB 300k ov534 1415:2000 Sony HD Eye for PS3 (SLEH 00201) pac207 145f:013a Trust WB-1300N +vc032x 15b8:6001 HP 2.0 Megapixel vc032x 15b8:6002 HP 2.0 Megapixel rz406aa spca501 1776:501c Arowana 300K CMOS Camera t613 17a1:0128 TASCORP JPEG Webcam, NGS Cyclops -- cgit v1.2.3 From aeecea26234011c3fbf65ffa7d9c9525b486acab Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Thu, 26 Mar 2009 12:07:36 -0300 Subject: V4L/DVB (11225): v4lgrab: fix compilation warnings MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Documentation/video4linux/v4lgrab.c: In function ‘main’: Documentation/video4linux/v4lgrab.c:193: warning: ‘src_depth’ is used uninitialized in this function Documentation/video4linux/v4lgrab.c:108: warning: ‘b’ may be used uninitialized in this function Documentation/video4linux/v4lgrab.c:108: warning: ‘g’ may be used uninitialized in this function Documentation/video4linux/v4lgrab.c:108: warning: ‘r’ may be used uninitialized in this function Signed-off-by: Mauro Carvalho Chehab --- Documentation/video4linux/v4lgrab.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'Documentation') diff --git a/Documentation/video4linux/v4lgrab.c b/Documentation/video4linux/v4lgrab.c index d6e70bef8ad..05769cff100 100644 --- a/Documentation/video4linux/v4lgrab.c +++ b/Documentation/video4linux/v4lgrab.c @@ -105,8 +105,8 @@ int main(int argc, char ** argv) struct video_picture vpic; unsigned char *buffer, *src; - int bpp = 24, r, g, b; - unsigned int i, src_depth; + int bpp = 24, r = 0, g = 0, b = 0; + unsigned int i, src_depth = 16; if (fd < 0) { perror(VIDEO_DEV); -- cgit v1.2.3 From 25f3311acc3405dd0dace3571a41f450e6cc6a65 Mon Sep 17 00:00:00 2001 From: Jean Delvare Date: Mon, 30 Mar 2009 21:46:41 +0200 Subject: hwmon: (ds1621) Clean up documentation * The alarms sysfs file is deprecated, and individual alarm files are self-explanatory. * The driver doesn't implement high-reslution temperature readings so don't document that. Signed-off-by: Jean Delvare Cc: Aurelien Jarno --- Documentation/hwmon/ds1621 | 51 +++------------------------------------------- 1 file changed, 3 insertions(+), 48 deletions(-) (limited to 'Documentation') diff --git a/Documentation/hwmon/ds1621 b/Documentation/hwmon/ds1621 index 1fee6f1e6bc..5e97f333c4d 100644 --- a/Documentation/hwmon/ds1621 +++ b/Documentation/hwmon/ds1621 @@ -49,12 +49,9 @@ of up to +/- 0.5 degrees even when compared against precise temperature readings. Be sure to have a high vs. low temperature limit gap of al least 1.0 degree Celsius to avoid Tout "bouncing", though! -As for alarms, you can read the alarm status of the DS1621 via the 'alarms' -/sys file interface. The result consists mainly of bit 6 and 5 of the -configuration register of the chip; bit 6 (0x40 or 64) is the high alarm -bit and bit 5 (0x20 or 32) the low one. These bits are set when the high or -low limits are met or exceeded and are reset by the module as soon as the -respective temperature ranges are left. +The alarm bits are set when the high or low limits are met or exceeded and +are reset by the module as soon as the respective temperature ranges are +left. The alarm registers are in no way suitable to find out about the actual status of Tout. They will only tell you about its history, whether or not @@ -64,45 +61,3 @@ with neither of the alarms set. Temperature conversion of the DS1621 takes up to 1000ms; internal access to non-volatile registers may last for 10ms or below. - -High Accuracy Temperature Reading ---------------------------------- - -As said before, the temperature issued via the 9-bit i2c-bus data is -somewhat arbitrary. Internally, the temperature conversion is of a -different kind that is explained (not so...) well in the DS1621 data sheet. -To cut the long story short: Inside the DS1621 there are two oscillators, -both of them biassed by a temperature coefficient. - -Higher resolution of the temperature reading can be achieved using the -internal projection, which means taking account of REG_COUNT and REG_SLOPE -(the driver manages them): - -Taken from Dallas Semiconductors App Note 068: 'Increasing Temperature -Resolution on the DS1620' and App Note 105: 'High Resolution Temperature -Measurement with Dallas Direct-to-Digital Temperature Sensors' - -- Read the 9-bit temperature and strip the LSB (Truncate the .5 degs) -- The resulting value is TEMP_READ. -- Then, read REG_COUNT. -- And then, REG_SLOPE. - - TEMP = TEMP_READ - 0.25 + ((REG_SLOPE - REG_COUNT) / REG_SLOPE) - -Note that this is what the DONE bit in the DS1621 configuration register is -good for: Internally, one temperature conversion takes up to 1000ms. Before -that conversion is complete you will not be able to read valid things out -of REG_COUNT and REG_SLOPE. The DONE bit, as you may have guessed by now, -tells you whether the conversion is complete ("done", in plain English) and -thus, whether the values you read are good or not. - -The DS1621 has two modes of operation: "Continuous" conversion, which can -be understood as the default stand-alone mode where the chip gets the -temperature and controls external devices via its Tout pin or tells other -i2c's about it if they care. The other mode is called "1SHOT", that means -that it only figures out about the temperature when it is explicitly told -to do so; this can be seen as power saving mode. - -Now if you want to read REG_COUNT and REG_SLOPE, you have to either stop -the continuous conversions until the contents of these registers are valid, -or, in 1SHOT mode, you have to have one conversion made. -- cgit v1.2.3 From 237c8d2f54ff12bd4fea1a9d18a94ae5810271d3 Mon Sep 17 00:00:00 2001 From: Gong Jun Date: Mon, 30 Mar 2009 21:46:42 +0200 Subject: hwmon: (w83627ehf) Add support for W83667HG Add initial support for the Nuvoton W83667HG chip to the w83627ehf driver. It has been tested on ASUS P5QL PRO by Gong Jun. At the moment there is still a usability issue which is that only in6 or temp3 can be present on the W83667HG, so the driver shouldn't expose both. This will be addressed later. Signed-off-by: Gong Jun Acked-by: David Hubbard Signed-off-by: Jean Delvare --- Documentation/hwmon/w83627ehf | 29 ++++++++++++++++++++--------- 1 file changed, 20 insertions(+), 9 deletions(-) (limited to 'Documentation') diff --git a/Documentation/hwmon/w83627ehf b/Documentation/hwmon/w83627ehf index d6e1ae30fa6..b6eb59384bb 100644 --- a/Documentation/hwmon/w83627ehf +++ b/Documentation/hwmon/w83627ehf @@ -2,30 +2,40 @@ Kernel driver w83627ehf ======================= Supported chips: - * Winbond W83627EHF/EHG/DHG (ISA access ONLY) + * Winbond W83627EHF/EHG (ISA access ONLY) Prefix: 'w83627ehf' Addresses scanned: ISA address retrieved from Super I/O registers Datasheet: - http://www.winbond-usa.com/products/winbond_products/pdfs/PCIC/W83627EHF_%20W83627EHGb.pdf - DHG datasheet confidential. + http://www.nuvoton.com.tw/NR/rdonlyres/A6A258F0-F0C9-4F97-81C0-C4D29E7E943E/0/W83627EHF.pdf + * Winbond W83627DHG + Prefix: 'w83627dhg' + Addresses scanned: ISA address retrieved from Super I/O registers + Datasheet: + http://www.nuvoton.com.tw/NR/rdonlyres/7885623D-A487-4CF9-A47F-30C5F73D6FE6/0/W83627DHG.pdf + * Winbond W83667HG + Prefix: 'w83667hg' + Addresses scanned: ISA address retrieved from Super I/O registers + Datasheet: not available Authors: Jean Delvare Yuan Mu (Winbond) Rudolf Marek David Hubbard + Gong Jun Description ----------- -This driver implements support for the Winbond W83627EHF, W83627EHG, and -W83627DHG super I/O chips. We will refer to them collectively as Winbond chips. +This driver implements support for the Winbond W83627EHF, W83627EHG, +W83627DHG and W83667HG super I/O chips. We will refer to them collectively +as Winbond chips. The chips implement three temperature sensors, five fan rotation speed sensors, ten analog voltage sensors (only nine for the 627DHG), one -VID (6 pins for the 627EHF/EHG, 8 pins for the 627DHG), alarms with beep -warnings (control unimplemented), and some automatic fan regulation -strategies (plus manual fan control mode). +VID (6 pins for the 627EHF/EHG, 8 pins for the 627DHG and 667HG), alarms +with beep warnings (control unimplemented), and some automatic fan +regulation strategies (plus manual fan control mode). Temperatures are measured in degrees Celsius and measurement resolution is 1 degC for temp1 and 0.5 degC for temp2 and temp3. An alarm is triggered when @@ -54,7 +64,8 @@ follows: temp1 -> pwm1 temp2 -> pwm2 temp3 -> pwm3 -prog -> pwm4 (the programmable setting is not supported by the driver) +prog -> pwm4 (not on 667HG; the programmable setting is not supported by + the driver) /sys files ---------- -- cgit v1.2.3 From fb4504fe84b09cbf49fda19e6630a1003d79656a Mon Sep 17 00:00:00 2001 From: Jean Delvare Date: Mon, 30 Mar 2009 21:46:43 +0200 Subject: Move the pcf8591 driver to hwmon Directory drivers/i2c/chips is going away, so drivers there must find new homes. For the pcf8591 driver, the best choice seems to be the hwmon subsystem. While the Philips PCF8591 device isn't a typical hardware monitoring chip, its DAC interface is compatible with the hwmon one, so it fits somewhat. If a better subsystem is ever created for ADC/DAC chips, the driver could be moved there. Signed-off-by: Jean Delvare Cc: Aurelien Jarno --- Documentation/hwmon/pcf8591 | 90 +++++++++++++++++++++++++++++++++++++++++ Documentation/i2c/chips/pcf8591 | 90 ----------------------------------------- 2 files changed, 90 insertions(+), 90 deletions(-) create mode 100644 Documentation/hwmon/pcf8591 delete mode 100644 Documentation/i2c/chips/pcf8591 (limited to 'Documentation') diff --git a/Documentation/hwmon/pcf8591 b/Documentation/hwmon/pcf8591 new file mode 100644 index 00000000000..5628fcf4207 --- /dev/null +++ b/Documentation/hwmon/pcf8591 @@ -0,0 +1,90 @@ +Kernel driver pcf8591 +===================== + +Supported chips: + * Philips PCF8591 + Prefix: 'pcf8591' + Addresses scanned: I2C 0x48 - 0x4f + Datasheet: Publicly available at the Philips Semiconductor website + http://www.semiconductors.philips.com/pip/PCF8591P.html + +Authors: + Aurelien Jarno + valuable contributions by Jan M. Sendler , + Jean Delvare + + +Description +----------- +The PCF8591 is an 8-bit A/D and D/A converter (4 analog inputs and one +analog output) for the I2C bus produced by Philips Semiconductors. It +is designed to provide a byte I2C interface to up to 4 separate devices. + +The PCF8591 has 4 analog inputs programmable as single-ended or +differential inputs : +- mode 0 : four single ended inputs + Pins AIN0 to AIN3 are single ended inputs for channels 0 to 3 + +- mode 1 : three differential inputs + Pins AIN3 is the common negative differential input + Pins AIN0 to AIN2 are positive differential inputs for channels 0 to 2 + +- mode 2 : single ended and differential mixed + Pins AIN0 and AIN1 are single ended inputs for channels 0 and 1 + Pins AIN2 is the positive differential input for channel 3 + Pins AIN3 is the negative differential input for channel 3 + +- mode 3 : two differential inputs + Pins AIN0 is the positive differential input for channel 0 + Pins AIN1 is the negative differential input for channel 0 + Pins AIN2 is the positive differential input for channel 1 + Pins AIN3 is the negative differential input for channel 1 + +See the datasheet for details. + +Module parameters +----------------- + +* input_mode int + + Analog input mode: + 0 = four single ended inputs + 1 = three differential inputs + 2 = single ended and differential mixed + 3 = two differential inputs + + +Accessing PCF8591 via /sys interface +------------------------------------- + +! Be careful ! +The PCF8591 is plainly impossible to detect ! Stupid chip. +So every chip with address in the interval [48..4f] is +detected as PCF8591. If you have other chips in this address +range, the workaround is to load this module after the one +for your others chips. + +On detection (i.e. insmod, modprobe et al.), directories are being +created for each detected PCF8591: + +/sys/bus/devices/<0>-<1>/ +where <0> is the bus the chip was detected on (e. g. i2c-0) +and <1> the chip address ([48..4f]) + +Inside these directories, there are such files: +in0, in1, in2, in3, out0_enable, out0_output, name + +Name contains chip name. + +The in0, in1, in2 and in3 files are RO. Reading gives the value of the +corresponding channel. Depending on the current analog inputs configuration, +files in2 and/or in3 do not exist. Values range are from 0 to 255 for single +ended inputs and -128 to +127 for differential inputs (8-bit ADC). + +The out0_enable file is RW. Reading gives "1" for analog output enabled and +"0" for analog output disabled. Writing accepts "0" and "1" accordingly. + +The out0_output file is RW. Writing a number between 0 and 255 (8-bit DAC), send +the value to the digital-to-analog converter. Note that a voltage will +only appears on AOUT pin if aout0_enable equals 1. Reading returns the last +value written. diff --git a/Documentation/i2c/chips/pcf8591 b/Documentation/i2c/chips/pcf8591 deleted file mode 100644 index 5628fcf4207..00000000000 --- a/Documentation/i2c/chips/pcf8591 +++ /dev/null @@ -1,90 +0,0 @@ -Kernel driver pcf8591 -===================== - -Supported chips: - * Philips PCF8591 - Prefix: 'pcf8591' - Addresses scanned: I2C 0x48 - 0x4f - Datasheet: Publicly available at the Philips Semiconductor website - http://www.semiconductors.philips.com/pip/PCF8591P.html - -Authors: - Aurelien Jarno - valuable contributions by Jan M. Sendler , - Jean Delvare - - -Description ------------ -The PCF8591 is an 8-bit A/D and D/A converter (4 analog inputs and one -analog output) for the I2C bus produced by Philips Semiconductors. It -is designed to provide a byte I2C interface to up to 4 separate devices. - -The PCF8591 has 4 analog inputs programmable as single-ended or -differential inputs : -- mode 0 : four single ended inputs - Pins AIN0 to AIN3 are single ended inputs for channels 0 to 3 - -- mode 1 : three differential inputs - Pins AIN3 is the common negative differential input - Pins AIN0 to AIN2 are positive differential inputs for channels 0 to 2 - -- mode 2 : single ended and differential mixed - Pins AIN0 and AIN1 are single ended inputs for channels 0 and 1 - Pins AIN2 is the positive differential input for channel 3 - Pins AIN3 is the negative differential input for channel 3 - -- mode 3 : two differential inputs - Pins AIN0 is the positive differential input for channel 0 - Pins AIN1 is the negative differential input for channel 0 - Pins AIN2 is the positive differential input for channel 1 - Pins AIN3 is the negative differential input for channel 1 - -See the datasheet for details. - -Module parameters ------------------ - -* input_mode int - - Analog input mode: - 0 = four single ended inputs - 1 = three differential inputs - 2 = single ended and differential mixed - 3 = two differential inputs - - -Accessing PCF8591 via /sys interface -------------------------------------- - -! Be careful ! -The PCF8591 is plainly impossible to detect ! Stupid chip. -So every chip with address in the interval [48..4f] is -detected as PCF8591. If you have other chips in this address -range, the workaround is to load this module after the one -for your others chips. - -On detection (i.e. insmod, modprobe et al.), directories are being -created for each detected PCF8591: - -/sys/bus/devices/<0>-<1>/ -where <0> is the bus the chip was detected on (e. g. i2c-0) -and <1> the chip address ([48..4f]) - -Inside these directories, there are such files: -in0, in1, in2, in3, out0_enable, out0_output, name - -Name contains chip name. - -The in0, in1, in2 and in3 files are RO. Reading gives the value of the -corresponding channel. Depending on the current analog inputs configuration, -files in2 and/or in3 do not exist. Values range are from 0 to 255 for single -ended inputs and -128 to +127 for differential inputs (8-bit ADC). - -The out0_enable file is RW. Reading gives "1" for analog output enabled and -"0" for analog output disabled. Writing accepts "0" and "1" accordingly. - -The out0_output file is RW. Writing a number between 0 and 255 (8-bit DAC), send -the value to the digital-to-analog converter. Note that a voltage will -only appears on AOUT pin if aout0_enable equals 1. Reading returns the last -value written. -- cgit v1.2.3 From ec19920944246b4686c7772a58507a20c361dc9d Mon Sep 17 00:00:00 2001 From: Jean Delvare Date: Mon, 30 Mar 2009 21:46:44 +0200 Subject: hwmon: Define a standard interface for chassis intrusion detection Define a standard interface for the chassis intrusion detection feature some hardware monitoring chips have. Some drivers have custom sysfs entries for it, but a standard interface would allow integration with user-space (namely libsensors.) Signed-off-by: Jean Delvare Acked-by: Hans de Goede Acked-by: Matt Roberds --- Documentation/hwmon/sysfs-interface | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) (limited to 'Documentation') diff --git a/Documentation/hwmon/sysfs-interface b/Documentation/hwmon/sysfs-interface index 6dbfd5efd99..2f10ce6a879 100644 --- a/Documentation/hwmon/sysfs-interface +++ b/Documentation/hwmon/sysfs-interface @@ -365,6 +365,7 @@ energy[1-*]_input Cumulative energy use Unit: microJoule RO + ********** * Alarms * ********** @@ -453,6 +454,27 @@ beep_mask Bitmask for beep. RW +*********************** +* Intrusion detection * +*********************** + +intrusion[0-*]_alarm + Chassis intrusion detection + 0: OK + 1: intrusion detected + RW + Contrary to regular alarm flags which clear themselves + automatically when read, this one sticks until cleared by + the user. This is done by writing 0 to the file. Writing + other values is unsupported. + +intrusion[0-*]_beep + Chassis intrusion beep + 0: disable + 1: enable + RW + + sysfs attribute writes interpretation ------------------------------------- -- cgit v1.2.3 From 99b76233803beab302123d243eea9e41149804f3 Mon Sep 17 00:00:00 2001 From: Alexey Dobriyan Date: Wed, 25 Mar 2009 22:48:06 +0300 Subject: proc 2/2: remove struct proc_dir_entry::owner Setting ->owner as done currently (pde->owner = THIS_MODULE) is racy as correctly noted at bug #12454. Someone can lookup entry with NULL ->owner, thus not pinning enything, and release it later resulting in module refcount underflow. We can keep ->owner and supply it at registration time like ->proc_fops and ->data. But this leaves ->owner as easy-manipulative field (just one C assignment) and somebody will forget to unpin previous/pin current module when switching ->owner. ->proc_fops is declared as "const" which should give some thoughts. ->read_proc/->write_proc were just fixed to not require ->owner for protection. rmmod'ed directories will be empty and return "." and ".." -- no harm. And directories with tricky enough readdir and lookup shouldn't be modular. We definitely don't want such modular code. Removing ->owner will also make PDE smaller. So, let's nuke it. Kudos to Jeff Layton for reminding about this, let's say, oversight. http://bugzilla.kernel.org/show_bug.cgi?id=12454 Signed-off-by: Alexey Dobriyan --- Documentation/DocBook/procfs_example.c | 9 --------- 1 file changed, 9 deletions(-) (limited to 'Documentation') diff --git a/Documentation/DocBook/procfs_example.c b/Documentation/DocBook/procfs_example.c index 8c6396e4bf3..a5b11793b1e 100644 --- a/Documentation/DocBook/procfs_example.c +++ b/Documentation/DocBook/procfs_example.c @@ -117,9 +117,6 @@ static int __init init_procfs_example(void) rv = -ENOMEM; goto out; } - - example_dir->owner = THIS_MODULE; - /* create jiffies using convenience function */ jiffies_file = create_proc_read_entry("jiffies", 0444, example_dir, @@ -130,8 +127,6 @@ static int __init init_procfs_example(void) goto no_jiffies; } - jiffies_file->owner = THIS_MODULE; - /* create foo and bar files using same callback * functions */ @@ -146,7 +141,6 @@ static int __init init_procfs_example(void) foo_file->data = &foo_data; foo_file->read_proc = proc_read_foobar; foo_file->write_proc = proc_write_foobar; - foo_file->owner = THIS_MODULE; bar_file = create_proc_entry("bar", 0644, example_dir); if(bar_file == NULL) { @@ -159,7 +153,6 @@ static int __init init_procfs_example(void) bar_file->data = &bar_data; bar_file->read_proc = proc_read_foobar; bar_file->write_proc = proc_write_foobar; - bar_file->owner = THIS_MODULE; /* create symlink */ symlink = proc_symlink("jiffies_too", example_dir, @@ -169,8 +162,6 @@ static int __init init_procfs_example(void) goto no_symlink; } - symlink->owner = THIS_MODULE; - /* everything OK */ printk(KERN_INFO "%s %s initialised\n", MODULE_NAME, MODULE_VERS); -- cgit v1.2.3 From 11373542344bdc35be1e6e68b0baadd1b6f7acbb Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Tue, 31 Mar 2009 15:18:37 +1100 Subject: Documentation/md.txt update Update md.txt to reflect recent changes in a number of sysfs attributes. Signed-off-by: NeilBrown --- Documentation/md.txt | 37 ++++++++++++++++++++++++++++++------- 1 file changed, 30 insertions(+), 7 deletions(-) (limited to 'Documentation') diff --git a/Documentation/md.txt b/Documentation/md.txt index 1da9d1b1793..4edd39ec7db 100644 --- a/Documentation/md.txt +++ b/Documentation/md.txt @@ -164,15 +164,19 @@ All md devices contain: raid_disks a text file with a simple number indicating the number of devices in a fully functional array. If this is not yet known, the file - will be empty. If an array is being resized (not currently - possible) this will contain the larger of the old and new sizes. - Some raid level (RAID1) allow this value to be set while the - array is active. This will reconfigure the array. Otherwise - it can only be set while assembling an array. + will be empty. If an array is being resized this will contain + the new number of devices. + Some raid levels allow this value to be set while the array is + active. This will reconfigure the array. Otherwise it can only + be set while assembling an array. + A change to this attribute will not be permitted if it would + reduce the size of the array. To reduce the number of drives + in an e.g. raid5, the array size must first be reduced by + setting the 'array_size' attribute. chunk_size - This is the size if bytes for 'chunks' and is only relevant to - raid levels that involve striping (1,4,5,6,10). The address space + This is the size in bytes for 'chunks' and is only relevant to + raid levels that involve striping (0,4,5,6,10). The address space of the array is conceptually divided into chunks and consecutive chunks are striped onto neighbouring devices. The size should be at least PAGE_SIZE (4k) and should be a power @@ -183,6 +187,20 @@ All md devices contain: simply a number that is interpretted differently by different levels. It can be written while assembling an array. + array_size + This can be used to artificially constrain the available space in + the array to be less than is actually available on the combined + devices. Writing a number (in Kilobytes) which is less than + the available size will set the size. Any reconfiguration of the + array (e.g. adding devices) will not cause the size to change. + Writing the word 'default' will cause the effective size of the + array to be whatever size is actually available based on + 'level', 'chunk_size' and 'component_size'. + + This can be used to reduce the size of the array before reducing + the number of devices in a raid4/5/6, or to support external + metadata formats which mandate such clipping. + reshape_position This is either "none" or a sector number within the devices of the array where "reshape" is up to. If this is set, the three @@ -207,6 +225,11 @@ All md devices contain: about the array. It can be 0.90 (traditional format), 1.0, 1.1, 1.2 (newer format in varying locations) or "none" indicating that the kernel isn't managing metadata at all. + Alternately it can be "external:" followed by a string which + is set by user-space. This indicates that metadata is managed + by a user-space program. Any device failure or other event that + requires a metadata update will cause array activity to be + suspended until the event is acknowledged. resync_start The point at which resync should start. If no resync is needed, -- cgit v1.2.3 From 853116a10544206b6b2cf42ebc9d78fba2668888 Mon Sep 17 00:00:00 2001 From: David Brownell Date: Wed, 14 Jan 2009 23:03:17 -0800 Subject: regulator: add get_status() Based on previous LKML discussions: * Update docs for regulator sysfs class attributes to highlight the fact that all current attributes are intended to be control inputs, including notably "state" and "opmode" which previously implied otherwise. * Define a new regulator driver get_status() method, which is the first method reporting regulator outputs instead of inputs. It can report on/off and error status; or instead of simply "on", report the actual operating mode. For the moment, this is a sysfs-only interface, not accessible to regulator clients. Such clients can use the current notification interfaces to detect errors, if the regulator reports them. Signed-off-by: David Brownell Signed-off-by: Liam Girdwood --- Documentation/ABI/testing/sysfs-class-regulator | 57 +++++++++++++++++++++---- 1 file changed, 48 insertions(+), 9 deletions(-) (limited to 'Documentation') diff --git a/Documentation/ABI/testing/sysfs-class-regulator b/Documentation/ABI/testing/sysfs-class-regulator index 873ef1fc156..e091fa87379 100644 --- a/Documentation/ABI/testing/sysfs-class-regulator +++ b/Documentation/ABI/testing/sysfs-class-regulator @@ -4,8 +4,8 @@ KernelVersion: 2.6.26 Contact: Liam Girdwood Description: Some regulator directories will contain a field called - state. This reports the regulator enable status, for - regulators which can report that value. + state. This reports the regulator enable control, for + regulators which can report that input value. This will be one of the following strings: @@ -14,16 +14,54 @@ Description: 'unknown' 'enabled' means the regulator output is ON and is supplying - power to the system. + power to the system (assuming no error prevents it). 'disabled' means the regulator output is OFF and is not - supplying power to the system.. + supplying power to the system (unless some non-Linux + control has enabled it). 'unknown' means software cannot determine the state, or the reported state is invalid. NOTE: this field can be used in conjunction with microvolts - and microamps to determine regulator output levels. + or microamps to determine configured regulator output levels. + + +What: /sys/class/regulator/.../status +Description: + Some regulator directories will contain a field called + "status". This reports the current regulator status, for + regulators which can report that output value. + + This will be one of the following strings: + + off + on + error + fast + normal + idle + standby + + "off" means the regulator is not supplying power to the + system. + + "on" means the regulator is supplying power to the system, + and the regulator can't report a detailed operation mode. + + "error" indicates an out-of-regulation status such as being + disabled due to thermal shutdown, or voltage being unstable + because of problems with the input power supply. + + "fast", "normal", "idle", and "standby" are all detailed + regulator operation modes (described elsewhere). They + imply "on", but provide more detail. + + Note that regulator status is a function of many inputs, + not limited to control inputs from Linux. For example, + the actual load presented may trigger "error" status; or + a regulator may be enabled by another user, even though + Linux did not enable it. What: /sys/class/regulator/.../type @@ -58,7 +96,7 @@ Description: Some regulator directories will contain a field called microvolts. This holds the regulator output voltage setting measured in microvolts (i.e. E-6 Volts), for regulators - which can report that voltage. + which can report the control input for voltage. NOTE: This value should not be used to determine the regulator output voltage level as this value is the same regardless of @@ -73,7 +111,7 @@ Description: Some regulator directories will contain a field called microamps. This holds the regulator output current limit setting measured in microamps (i.e. E-6 Amps), for regulators - which can report that current. + which can report the control input for a current limit. NOTE: This value should not be used to determine the regulator output current level as this value is the same regardless of @@ -87,7 +125,7 @@ Contact: Liam Girdwood Description: Some regulator directories will contain a field called opmode. This holds the current regulator operating mode, - for regulators which can report it. + for regulators which can report that control input value. The opmode value can be one of the following strings: @@ -101,7 +139,8 @@ Description: NOTE: This value should not be used to determine the regulator output operating mode as this value is the same regardless of - whether the regulator is enabled or disabled. + whether the regulator is enabled or disabled. A "status" + attribute may be available to determine the actual mode. What: /sys/class/regulator/.../min_microvolts -- cgit v1.2.3 From 214c8adb87b880690b103e86baffc46f8288fa62 Mon Sep 17 00:00:00 2001 From: Boaz Harrosh Date: Tue, 28 Oct 2008 17:22:01 +0200 Subject: exofs: Documentation Added some documentation in exofs.txt, as well as a BUGS file. For further reading, operation instructions, example scripts and up to date infomation and code please see: http://open-osd.org Signed-off-by: Boaz Harrosh --- Documentation/filesystems/exofs.txt | 176 ++++++++++++++++++++++++++++++++++++ 1 file changed, 176 insertions(+) create mode 100644 Documentation/filesystems/exofs.txt (limited to 'Documentation') diff --git a/Documentation/filesystems/exofs.txt b/Documentation/filesystems/exofs.txt new file mode 100644 index 00000000000..0ced74c2f73 --- /dev/null +++ b/Documentation/filesystems/exofs.txt @@ -0,0 +1,176 @@ +=============================================================================== +WHAT IS EXOFS? +=============================================================================== + +exofs is a file system that uses an OSD and exports the API of a normal Linux +file system. Users access exofs like any other local file system, and exofs +will in turn issue commands to the local OSD initiator. + +OSD is a new T10 command set that views storage devices not as a large/flat +array of sectors but as a container of objects, each having a length, quota, +time attributes and more. Each object is addressed by a 64bit ID, and is +contained in a 64bit ID partition. Each object has associated attributes +attached to it, which are integral part of the object and provide metadata about +the object. The standard defines some common obligatory attributes, but user +attributes can be added as needed. + +=============================================================================== +ENVIRONMENT +=============================================================================== + +To use this file system, you need to have an object store to run it on. You +may download a target from: +http://open-osd.org + +See Documentation/scsi/osd.txt for how to setup a working osd environment. + +=============================================================================== +USAGE +=============================================================================== + +1. Download and compile exofs and open-osd initiator: + You need an external Kernel source tree or kernel headers from your + distribution. (anything based on 2.6.26 or later). + + a. download open-osd including exofs source using: + [parent-directory]$ git clone git://git.open-osd.org/open-osd.git + + b. Build the library module like this: + [parent-directory]$ make -C KSRC=$(KER_DIR) open-osd + + This will build both the open-osd initiator as well as the exofs kernel + module. Use whatever parameters you compiled your Kernel with and + $(KER_DIR) above pointing to the Kernel you compile against. See the file + open-osd/top-level-Makefile for an example. + +2. Get the OSD initiator and target set up properly, and login to the target. + See Documentation/scsi/osd.txt for farther instructions. Also see ./do-osd + for example script that does all these steps. + +3. Insmod the exofs.ko module: + [exofs]$ insmod exofs.ko + +4. Make sure the directory where you want to mount exists. If not, create it. + (For example, mkdir /mnt/exofs) + +5. At first run you will need to invoke the mkfs.exofs application + + As an example, this will create the file system on: + /dev/osd0 partition ID 65536 + + mkfs.exofs --pid=65536 --format /dev/osd0 + + The --format is optional if not specified no OSD_FORMAT will be + preformed and a clean file system will be created in the specified pid, + in the available space of the target. (Use --format=size_in_meg to limit + the total LUN space available) + + If pid already exist it will be deleted and a new one will be created in it's + place. Be careful. + + An exofs lives inside a single OSD partition. You can create multiple exofs + filesystems on the same device using multiple pids. + + (run mkfs.exofs without any parameters for usage help message) + +6. Mount the file system. + + For example, to mount /dev/osd0, partition ID 0x10000 on /mnt/exofs: + + mount -t exofs -o pid=65536 /dev/osd0 /mnt/exofs/ + +7. For reference (See do-exofs example script): + do-exofs start - an example of how to perform the above steps. + do-exofs stop - an example of how to unmount the file system. + do-exofs format - an example of how to format and mkfs a new exofs. + +8. Extra compilation flags (uncomment in fs/exofs/Kbuild): + CONFIG_EXOFS_DEBUG - for debug messages and extra checks. + +=============================================================================== +exofs mount options +=============================================================================== +Similar to any mount command: + mount -t exofs -o exofs_options /dev/osdX mount_exofs_directory + +Where: + -t exofs: specifies the exofs file system + + /dev/osdX: X is a decimal number. /dev/osdX was created after a successful + login into an OSD target. + + mount_exofs_directory: The directory to mount the file system on + + exofs specific options: Options are separated by commas (,) + pid= - The partition number to mount/create as + container of the filesystem. + This option is mandatory + to= - Timeout in ticks for a single command + default is (60 * HZ) [for debugging only] + +=============================================================================== +DESIGN +=============================================================================== + +* The file system control block (AKA on-disk superblock) resides in an object + with a special ID (defined in common.h). + Information included in the file system control block is used to fill the + in-memory superblock structure at mount time. This object is created before + the file system is used by mkexofs.c It contains information such as: + - The file system's magic number + - The next inode number to be allocated + +* Each file resides in its own object and contains the data (and it will be + possible to extend the file over multiple objects, though this has not been + implemented yet). + +* A directory is treated as a file, and essentially contains a list of pairs for files that are found in that directory. The object + IDs correspond to the files' inode numbers and will be allocated according to + a bitmap (stored in a separate object). Now they are allocated using a + counter. + +* Each file's control block (AKA on-disk inode) is stored in its object's + attributes. This applies to both regular files and other types (directories, + device files, symlinks, etc.). + +* Credentials are generated per object (inode and superblock) when they is + created in memory (read off disk or created). The credential works for all + operations and is used as long as the object remains in memory. + +* Async OSD operations are used whenever possible, but the target may execute + them out of order. The operations that concern us are create, delete, + readpage, writepage, update_inode, and truncate. The following pairs of + operations should execute in the order written, and we need to prevent them + from executing in reverse order: + - The following are handled with the OBJ_CREATED and OBJ_2BCREATED + flags. OBJ_CREATED is set when we know the object exists on the OSD - + in create's callback function, and when we successfully do a read_inode. + OBJ_2BCREATED is set in the beginning of the create function, so we + know that we should wait. + - create/delete: delete should wait until the object is created + on the OSD. + - create/readpage: readpage should be able to return a page + full of zeroes in this case. If there was a write already + en-route (i.e. create, writepage, readpage) then the page + would be locked, and so it would really be the same as + create/writepage. + - create/writepage: if writepage is called for a sync write, it + should wait until the object is created on the OSD. + Otherwise, it should just return. + - create/truncate: truncate should wait until the object is + created on the OSD. + - create/update_inode: update_inode should wait until the + object is created on the OSD. + - Handled by VFS locks: + - readpage/delete: shouldn't happen because of page lock. + - writepage/delete: shouldn't happen because of page lock. + - readpage/writepage: shouldn't happen because of page lock. + +=============================================================================== +LICENSE/COPYRIGHT +=============================================================================== +The exofs file system is based on ext2 v0.5b (distributed with the Linux kernel +version 2.6.10). All files include the original copyrights, and the license +is GPL version 2 (only version 2, as is true for the Linux kernel). The +Linux kernel can be downloaded from www.kernel.org. -- cgit v1.2.3 From 2584e517320bd48dc8d20e38a2621a2dbe58fade Mon Sep 17 00:00:00 2001 From: Ravikiran G Thirumalai Date: Tue, 31 Mar 2009 15:21:26 -0700 Subject: mm: reintroduce and deprecate rlimit based access for SHM_HUGETLB Allow non root users with sufficient mlock rlimits to be able to allocate hugetlb backed shm for now. Deprecate this though. This is being deprecated because the mlock based rlimit checks for SHM_HUGETLB is not consistent with mmap based huge page allocations. Signed-off-by: Ravikiran Thirumalai Reviewed-by: Mel Gorman Cc: William Lee Irwin III Cc: Adam Litke Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/feature-removal-schedule.txt | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'Documentation') diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 5e02b83ac12..ea7d1bdad34 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -311,6 +311,18 @@ Who: Vlad Yasevich --------------------------- +What: Ability for non root users to shm_get hugetlb pages based on mlock + resource limits +When: 2.6.31 +Why: Non root users need to be part of /proc/sys/vm/hugetlb_shm_group or + have CAP_IPC_LOCK to be able to allocate shm segments backed by + huge pages. The mlock based rlimit check to allow shm hugetlb is + inconsistent with mmap based allocations. Hence it is being + deprecated. +Who: Ravikiran Thirumalai + +--------------------------- + What: CONFIG_THERMAL_HWMON When: January 2009 Why: This option was introduced just to allow older lm-sensors userspace -- cgit v1.2.3 From c2ec175c39f62949438354f603f4aa170846aabb Mon Sep 17 00:00:00 2001 From: Nick Piggin Date: Tue, 31 Mar 2009 15:23:21 -0700 Subject: mm: page_mkwrite change prototype to match fault Change the page_mkwrite prototype to take a struct vm_fault, and return VM_FAULT_xxx flags. There should be no functional change. This makes it possible to return much more detailed error information to the VM (and also can provide more information eg. virtual_address to the driver, which might be important in some special cases). This is required for a subsequent fix. And will also make it easier to merge page_mkwrite() with fault() in future. Signed-off-by: Nick Piggin Cc: Chris Mason Cc: Trond Myklebust Cc: Miklos Szeredi Cc: Steven Whitehouse Cc: Mark Fasheh Cc: Joel Becker Cc: Artem Bityutskiy Cc: Felix Blyakher Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/filesystems/Locking | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index 4e78ce67784..76efe5b71d7 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -505,7 +505,7 @@ prototypes: void (*open)(struct vm_area_struct*); void (*close)(struct vm_area_struct*); int (*fault)(struct vm_area_struct*, struct vm_fault *); - int (*page_mkwrite)(struct vm_area_struct *, struct page *); + int (*page_mkwrite)(struct vm_area_struct *, struct vm_fault *); int (*access)(struct vm_area_struct *, unsigned long, void*, int, int); locking rules: -- cgit v1.2.3 From c2d7543851849a6923680cdd7e1047ed1a84a1c5 Mon Sep 17 00:00:00 2001 From: Eric Sandeen Date: Tue, 31 Mar 2009 15:23:46 -0700 Subject: filesystem freeze: allow SysRq emergency thaw to thaw frozen filesystems Now that the filesystem freeze operation has been elevated to the VFS, and is just an ioctl away, some sort of safety net for unintentionally frozen root filesystems may be in order. The timeout thaw originally proposed did not get merged, but perhaps something like this would be useful in emergencies. For example, freeze /path/to/mountpoint may freeze your root filesystem if you forgot that you had that unmounted. I chose 'j' as the last remaining character other than 'h' which is sort of reserved for help (because help is generated on any unknown character). I've tested this on a non-root fs with multiple (nested) freezers, as well as on a system rendered unresponsive due to a frozen root fs. [randy.dunlap@oracle.com: emergency thaw only if CONFIG_BLOCK enabled] Signed-off-by: Eric Sandeen Cc: Takashi Sato Signed-off-by: Randy Dunlap Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/sysrq.txt | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'Documentation') diff --git a/Documentation/sysrq.txt b/Documentation/sysrq.txt index 9e592c718af..afa2946892d 100644 --- a/Documentation/sysrq.txt +++ b/Documentation/sysrq.txt @@ -81,6 +81,8 @@ On all - write a character to /proc/sysrq-trigger. e.g.: 'i' - Send a SIGKILL to all processes, except for init. +'j' - Forcibly "Just thaw it" - filesystems frozen by the FIFREEZE ioctl. + 'k' - Secure Access Key (SAK) Kills all programs on the current virtual console. NOTE: See important comments below in SAK section. @@ -160,6 +162,9 @@ t'E'rm and k'I'll are useful if you have some sort of runaway process you are unable to kill any other way, especially if it's spawning other processes. +"'J'ust thaw it" is useful if your system becomes unresponsive due to a frozen +(probably root) filesystem via the FIFREEZE ioctl. + * Sometimes SysRq seems to get 'stuck' after using it, what can I do? ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ That happens to me, also. I've found that tapping shift, alt, and control -- cgit v1.2.3 From 3cdbbeebb77348176bd6a03fd86e11bc281c529e Mon Sep 17 00:00:00 2001 From: Daniel Mack Date: Tue, 31 Mar 2009 15:23:53 -0700 Subject: drivers/misc/isl29003.c: driver for the ISL29003 ambient light sensor Add a driver for Intersil's ISL29003 ambient light sensor device plus some documentation. Inspired by tsl2550.c, a driver for a similar device. It is put in drivers/misc for now until the industrial I/O framework gets merged. Signed-off-by: Daniel Mack Acked-by: Jonathan Cameron Cc: Jean Delvare Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/misc-devices/isl29003 | 62 +++++++++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) create mode 100644 Documentation/misc-devices/isl29003 (limited to 'Documentation') diff --git a/Documentation/misc-devices/isl29003 b/Documentation/misc-devices/isl29003 new file mode 100644 index 00000000000..c4ff5f38e01 --- /dev/null +++ b/Documentation/misc-devices/isl29003 @@ -0,0 +1,62 @@ +Kernel driver isl29003 +===================== + +Supported chips: +* Intersil ISL29003 +Prefix: 'isl29003' +Addresses scanned: none +Datasheet: +http://www.intersil.com/data/fn/fn7464.pdf + +Author: Daniel Mack + + +Description +----------- +The ISL29003 is an integrated light sensor with a 16-bit integrating type +ADC, I2C user programmable lux range select for optimized counts/lux, and +I2C multi-function control and monitoring capabilities. The internal ADC +provides 16-bit resolution while rejecting 50Hz and 60Hz flicker caused by +artificial light sources. + +The driver allows to set the lux range, the bit resolution, the operational +mode (see below) and the power state of device and can read the current lux +value, of course. + + +Detection +--------- + +The ISL29003 does not have an ID register which could be used to identify +it, so the detection routine will just try to read from the configured I2C +addess and consider the device to be present as soon as it ACKs the +transfer. + + +Sysfs entries +------------- + +range: + 0: 0 lux to 1000 lux (default) + 1: 0 lux to 4000 lux + 2: 0 lux to 16,000 lux + 3: 0 lux to 64,000 lux + +resolution: + 0: 2^16 cycles (default) + 1: 2^12 cycles + 2: 2^8 cycles + 3: 2^4 cycles + +mode: + 0: diode1's current (unsigned 16bit) (default) + 1: diode1's current (unsigned 16bit) + 2: difference between diodes (l1 - l2, signed 15bit) + +power_state: + 0: device is disabled (default) + 1: device is enabled + +lux (read only): + returns the value from the last sensor reading + -- cgit v1.2.3 From 2b872903c5d66bccdf4306a35e3e94d4da8555d3 Mon Sep 17 00:00:00 2001 From: Pavel Machek Date: Tue, 31 Mar 2009 15:24:25 -0700 Subject: hp_accel: small documentation updates Fix english in Documentation, add "how to test" description. Signed-off-by: Pavel Machek Cc: Eric Piel Cc: Vladimir Botka Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/hwmon/lis3lv02d | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-) (limited to 'Documentation') diff --git a/Documentation/hwmon/lis3lv02d b/Documentation/hwmon/lis3lv02d index 287f8c90265..effe949a728 100644 --- a/Documentation/hwmon/lis3lv02d +++ b/Documentation/hwmon/lis3lv02d @@ -1,11 +1,11 @@ Kernel driver lis3lv02d -================== +======================= Supported chips: * STMicroelectronics LIS3LV02DL and LIS3LV02DQ -Author: +Authors: Yan Burman Eric Piel @@ -15,7 +15,7 @@ Description This driver provides support for the accelerometer found in various HP laptops sporting the feature officially called "HP Mobile Data -Protection System 3D" or "HP 3D DriveGuard". It detect automatically +Protection System 3D" or "HP 3D DriveGuard". It detects automatically laptops with this sensor. Known models (for now the HP 2133, nc6420, nc2510, nc8510, nc84x0, nw9440 and nx9420) will have their axis automatically oriented on standard way (eg: you can directly play @@ -27,7 +27,7 @@ position - 3D position that the accelerometer reports. Format: "(x,y,z)" calibrate - read: values (x, y, z) that are used as the base for input class device operation. write: forces the base to be recalibrated with the current - position. + position. rate - reports the sampling rate of the accelerometer device in HZ This driver also provides an absolute input class device, allowing @@ -48,7 +48,7 @@ For better compatibility between the various laptops. The values reported by the accelerometer are converted into a "standard" organisation of the axes (aka "can play neverball out of the box"): * When the laptop is horizontal the position reported is about 0 for X and Y -and a positive value for Z + and a positive value for Z * If the left side is elevated, X increases (becomes positive) * If the front side (where the touchpad is) is elevated, Y decreases (becomes negative) @@ -59,3 +59,13 @@ email to the authors to add it to the database. When reporting a new laptop, please include the output of "dmidecode" plus the value of /sys/devices/platform/lis3lv02d/position in these four cases. +Q&A +--- + +Q: How do I safely simulate freefall? I have an HP "portable +workstation" which has about 3.5kg and a plastic case, so letting it +fall to the ground is out of question... + +A: The sensor is pretty sensitive, so your hands can do it. Lift it +into free space, follow the fall with your hands for like 10 +centimeters. That should be enough to trigger the detection. -- cgit v1.2.3 From 72f5de92e199f96cfcea125aefc76c138d8c553c Mon Sep 17 00:00:00 2001 From: Ira Snyder Date: Tue, 31 Mar 2009 15:24:29 -0700 Subject: hwmon: Add LTC4215 driver Add Linux support for the Linear Technology LTC4215 Hot Swap controller I2C monitoring interface. I have tested the driver with my board, and it appears to work fine. With the power supplies disabled, it reads 11.93V input, 1.93V output, no current and no power. With the supplies enabled, it reads 11.93V input, 11.98V output, no current, no power. I'm not drawing any current at the moment, so this is reasonable. The value in the sense register never reads anything except 0, so I expect to get zero from the current and power calculations. I didn't attempt to support changing any of the chip's settings or enabling the FET. I'm not sure even how to do that and still fit within the hwmon framework. :) Signed-off-by: Ira W. Snyder Cc: Jean Delvare Cc: "Mark M. Hoffman" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/hwmon/ltc4215 | 50 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+) create mode 100644 Documentation/hwmon/ltc4215 (limited to 'Documentation') diff --git a/Documentation/hwmon/ltc4215 b/Documentation/hwmon/ltc4215 new file mode 100644 index 00000000000..2e6a21eb656 --- /dev/null +++ b/Documentation/hwmon/ltc4215 @@ -0,0 +1,50 @@ +Kernel driver ltc4215 +===================== + +Supported chips: + * Linear Technology LTC4215 + Prefix: 'ltc4215' + Addresses scanned: 0x44 + Datasheet: + http://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1003,C1006,C1163,P17572,D12697 + +Author: Ira W. Snyder + + +Description +----------- + +The LTC4215 controller allows a board to be safely inserted and removed +from a live backplane. + + +Usage Notes +----------- + +This driver does not probe for LTC4215 devices, due to the fact that some +of the possible addresses are unfriendly to probing. You will need to use +the "force" parameter to tell the driver where to find the device. + +Example: the following will load the driver for an LTC4215 at address 0x44 +on I2C bus #0: +$ modprobe ltc4215 force=0,0x44 + + +Sysfs entries +------------- + +The LTC4215 has built-in limits for overvoltage, undervoltage, and +undercurrent warnings. This makes it very likely that the reference +circuit will be used. + +in1_input input voltage +in2_input output voltage + +in1_min_alarm input undervoltage alarm +in1_max_alarm input overvoltage alarm + +curr1_input current +curr1_max_alarm overcurrent alarm + +power1_input power usage +power1_alarm power bad alarm -- cgit v1.2.3 From 3f1c6ebf57b815ad709e89291e446935fee78f75 Mon Sep 17 00:00:00 2001 From: Anton Vorontsov Date: Tue, 31 Mar 2009 15:24:38 -0700 Subject: powerpc: add mmc-spi-slot bindings The bindings describes a case where MMC/SD/SDIO slot directly connected to a SPI bus. Such setups are widely used on embedded PowerPC boards. The patch also adds the mmc-spi-slot entry to the OpenFirmware modalias table. Signed-off-by: Anton Vorontsov Cc: David Brownell Cc: Benjamin Herrenschmidt Cc: Kumar Gala Cc: Grant Likely Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- .../powerpc/dts-bindings/mmc-spi-slot.txt | 23 ++++++++++++++++++++++ 1 file changed, 23 insertions(+) create mode 100644 Documentation/powerpc/dts-bindings/mmc-spi-slot.txt (limited to 'Documentation') diff --git a/Documentation/powerpc/dts-bindings/mmc-spi-slot.txt b/Documentation/powerpc/dts-bindings/mmc-spi-slot.txt new file mode 100644 index 00000000000..c39ac289195 --- /dev/null +++ b/Documentation/powerpc/dts-bindings/mmc-spi-slot.txt @@ -0,0 +1,23 @@ +MMC/SD/SDIO slot directly connected to a SPI bus + +Required properties: +- compatible : should be "mmc-spi-slot". +- reg : should specify SPI address (chip-select number). +- spi-max-frequency : maximum frequency for this device (Hz). +- voltage-ranges : two cells are required, first cell specifies minimum + slot voltage (mV), second cell specifies maximum slot voltage (mV). + Several ranges could be specified. +- gpios : (optional) may specify GPIOs in this order: Card-Detect GPIO, + Write-Protect GPIO. + +Example: + + mmc-slot@0 { + compatible = "fsl,mpc8323rdb-mmc-slot", + "mmc-spi-slot"; + reg = <0>; + gpios = <&qe_pio_d 14 1 + &qe_pio_d 15 0>; + voltage-ranges = <3300 3300>; + spi-max-frequency = <50000000>; + }; -- cgit v1.2.3 From ddb53d48da5b0e691f35e703ac29118747f86c99 Mon Sep 17 00:00:00 2001 From: Krzysztof Helt Date: Tue, 31 Mar 2009 15:25:40 -0700 Subject: fbdev: remove cyblafb driver A tridentfb driver has all the functionality of the cyblafb driver without the bugs of the latter. Changes to the tridentfb driver: - FBINFO_READS_FAST added to the tridentfb. The cyblafb used a blitter for scrolling which is faster than color expansion on Cyberblade chipsets. The blitter is slower on a discrete Blade3D core. Use the blitter for scrolling in the tridentfb only for integrated Blade3D cores. Now, scrolling speed is about equal for the tridentfb and the cyblafb. - a copyright notice addition is done on request of Jani Monoses (the first author of the tridentfb). Tested on AGP Blade3D card and PCChips M787CLR motherboard: VIA C3 cpu + VT8601 north bridge (aka Cyberblade/i1). Signed-off-by: Krzysztof Helt Cc: "Jani Monoses" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/fb/00-INDEX | 2 - Documentation/fb/cyblafb/bugs | 13 -- Documentation/fb/cyblafb/credits | 7 -- Documentation/fb/cyblafb/documentation | 17 --- Documentation/fb/cyblafb/fb.modes | 154 ----------------------- Documentation/fb/cyblafb/performance | 79 ------------ Documentation/fb/cyblafb/todo | 31 ----- Documentation/fb/cyblafb/usage | 217 --------------------------------- Documentation/fb/cyblafb/whatsnew | 29 ----- Documentation/fb/cyblafb/whycyblafb | 85 ------------- 10 files changed, 634 deletions(-) delete mode 100644 Documentation/fb/cyblafb/bugs delete mode 100644 Documentation/fb/cyblafb/credits delete mode 100644 Documentation/fb/cyblafb/documentation delete mode 100644 Documentation/fb/cyblafb/fb.modes delete mode 100644 Documentation/fb/cyblafb/performance delete mode 100644 Documentation/fb/cyblafb/todo delete mode 100644 Documentation/fb/cyblafb/usage delete mode 100644 Documentation/fb/cyblafb/whatsnew delete mode 100644 Documentation/fb/cyblafb/whycyblafb (limited to 'Documentation') diff --git a/Documentation/fb/00-INDEX b/Documentation/fb/00-INDEX index caabbd395e6..a618fd99c9f 100644 --- a/Documentation/fb/00-INDEX +++ b/Documentation/fb/00-INDEX @@ -11,8 +11,6 @@ aty128fb.txt - info on the ATI Rage128 frame buffer driver. cirrusfb.txt - info on the driver for Cirrus Logic chipsets. -cyblafb/ - - directory with documentation files related to the cyblafb driver. deferred_io.txt - an introduction to deferred IO. fbcon.txt diff --git a/Documentation/fb/cyblafb/bugs b/Documentation/fb/cyblafb/bugs deleted file mode 100644 index 9443a6d72cd..00000000000 --- a/Documentation/fb/cyblafb/bugs +++ /dev/null @@ -1,13 +0,0 @@ -Bugs -==== - -I currently don't know of any bug. Please do send reports to: - - linux-fbdev-devel@lists.sourceforge.net - - Knut_Petersen@t-online.de. - - -Untested features -================= - -All LCD stuff is untested. If it worked in tridentfb, it should work in -cyblafb. Please test and report the results to Knut_Petersen@t-online.de. diff --git a/Documentation/fb/cyblafb/credits b/Documentation/fb/cyblafb/credits deleted file mode 100644 index 0eb3b443dc2..00000000000 --- a/Documentation/fb/cyblafb/credits +++ /dev/null @@ -1,7 +0,0 @@ -Thanks to -========= - * Alan Hourihane, for writing the X trident driver - * Jani Monoses, for writing the tridentfb driver - * Antonino A. Daplas, for review of the first published - version of cyblafb and some code - * Jochen Hein, for testing and a helpfull bug report diff --git a/Documentation/fb/cyblafb/documentation b/Documentation/fb/cyblafb/documentation deleted file mode 100644 index bb1aac04842..00000000000 --- a/Documentation/fb/cyblafb/documentation +++ /dev/null @@ -1,17 +0,0 @@ -Available Documentation -======================= - -Apollo PLE 133 Chipset VT8601A North Bridge Datasheet, Rev. 1.82, October 22, -2001, available from VIA: - - http://www.viavpsd.com/product/6/15/DS8601A182.pdf - -The datasheet is incomplete, some registers that need to be programmed are not -explained at all and important bits are listed as "reserved". But you really -need the datasheet to understand the code. "p. xxx" comments refer to page -numbers of this document. - -XFree/XOrg drivers are available and of good quality, looking at the code -there is a good idea if the datasheet does not provide enough information -or if the datasheet seems to be wrong. - diff --git a/Documentation/fb/cyblafb/fb.modes b/Documentation/fb/cyblafb/fb.modes deleted file mode 100644 index fe0e5223ba8..00000000000 --- a/Documentation/fb/cyblafb/fb.modes +++ /dev/null @@ -1,154 +0,0 @@ -# -# Sample fb.modes file -# -# Provides an incomplete list of working modes for -# the cyberblade/i1 graphics core. -# -# The value 4294967256 is used instead of -40. Of course, -40 is not -# a really reasonable value, but chip design does not always follow -# logic. Believe me, it's ok, and it's the way the BIOS does it. -# -# fbset requires 4294967256 in fb.modes and -40 as an argument to -# the -t parameter. That's also not too reasonable, and it might change -# in the future or might even be differt for your current version. -# - -mode "640x480-50" - geometry 640 480 2048 4096 8 - timings 47619 4294967256 24 17 0 216 3 -endmode - -mode "640x480-60" - geometry 640 480 2048 4096 8 - timings 39682 4294967256 24 17 0 216 3 -endmode - -mode "640x480-70" - geometry 640 480 2048 4096 8 - timings 34013 4294967256 24 17 0 216 3 -endmode - -mode "640x480-72" - geometry 640 480 2048 4096 8 - timings 33068 4294967256 24 17 0 216 3 -endmode - -mode "640x480-75" - geometry 640 480 2048 4096 8 - timings 31746 4294967256 24 17 0 216 3 -endmode - -mode "640x480-80" - geometry 640 480 2048 4096 8 - timings 29761 4294967256 24 17 0 216 3 -endmode - -mode "640x480-85" - geometry 640 480 2048 4096 8 - timings 28011 4294967256 24 17 0 216 3 -endmode - -mode "800x600-50" - geometry 800 600 2048 4096 8 - timings 30303 96 24 14 0 136 11 -endmode - -mode "800x600-60" - geometry 800 600 2048 4096 8 - timings 25252 96 24 14 0 136 11 -endmode - -mode "800x600-70" - geometry 800 600 2048 4096 8 - timings 21645 96 24 14 0 136 11 -endmode - -mode "800x600-72" - geometry 800 600 2048 4096 8 - timings 21043 96 24 14 0 136 11 -endmode - -mode "800x600-75" - geometry 800 600 2048 4096 8 - timings 20202 96 24 14 0 136 11 -endmode - -mode "800x600-80" - geometry 800 600 2048 4096 8 - timings 18939 96 24 14 0 136 11 -endmode - -mode "800x600-85" - geometry 800 600 2048 4096 8 - timings 17825 96 24 14 0 136 11 -endmode - -mode "1024x768-50" - geometry 1024 768 2048 4096 8 - timings 19054 144 24 29 0 120 3 -endmode - -mode "1024x768-60" - geometry 1024 768 2048 4096 8 - timings 15880 144 24 29 0 120 3 -endmode - -mode "1024x768-70" - geometry 1024 768 2048 4096 8 - timings 13610 144 24 29 0 120 3 -endmode - -mode "1024x768-72" - geometry 1024 768 2048 4096 8 - timings 13232 144 24 29 0 120 3 -endmode - -mode "1024x768-75" - geometry 1024 768 2048 4096 8 - timings 12703 144 24 29 0 120 3 -endmode - -mode "1024x768-80" - geometry 1024 768 2048 4096 8 - timings 11910 144 24 29 0 120 3 -endmode - -mode "1024x768-85" - geometry 1024 768 2048 4096 8 - timings 11209 144 24 29 0 120 3 -endmode - -mode "1280x1024-50" - geometry 1280 1024 2048 4096 8 - timings 11114 232 16 39 0 160 3 -endmode - -mode "1280x1024-60" - geometry 1280 1024 2048 4096 8 - timings 9262 232 16 39 0 160 3 -endmode - -mode "1280x1024-70" - geometry 1280 1024 2048 4096 8 - timings 7939 232 16 39 0 160 3 -endmode - -mode "1280x1024-72" - geometry 1280 1024 2048 4096 8 - timings 7719 232 16 39 0 160 3 -endmode - -mode "1280x1024-75" - geometry 1280 1024 2048 4096 8 - timings 7410 232 16 39 0 160 3 -endmode - -mode "1280x1024-80" - geometry 1280 1024 2048 4096 8 - timings 6946 232 16 39 0 160 3 -endmode - -mode "1280x1024-85" - geometry 1280 1024 2048 4096 8 - timings 6538 232 16 39 0 160 3 -endmode diff --git a/Documentation/fb/cyblafb/performance b/Documentation/fb/cyblafb/performance deleted file mode 100644 index 8d15d5dfc6b..00000000000 --- a/Documentation/fb/cyblafb/performance +++ /dev/null @@ -1,79 +0,0 @@ -Speed -===== - -CyBlaFB is much faster than tridentfb and vesafb. Compare the performance data -for mode 1280x1024-[8,16,32]@61 Hz. - -Test 1: Cat a file with 2000 lines of 0 characters. -Test 2: Cat a file with 2000 lines of 80 characters. -Test 3: Cat a file with 2000 lines of 160 characters. - -All values show system time use in seconds, kernel 2.6.12 was used for -the measurements. 2.6.13 is a bit slower, 2.6.14 hopefully will include a -patch that speeds up kernel bitblitting a lot ( > 20%). - -+-----------+-----------------------------------------------------+ -| | not accelerated | -| TRIDENTFB +-----------------+-----------------+-----------------+ -| of 2.6.12 | 8 bpp | 16 bpp | 32 bpp | -| | noypan | ypan | noypan | ypan | noypan | ypan | -+-----------+--------+--------+--------+--------+--------+--------+ -| Test 1 | 4.31 | 4.33 | 6.05 | 12.81 | ---- | ---- | -| Test 2 | 67.94 | 5.44 | 123.16 | 14.79 | ---- | ---- | -| Test 3 | 131.36 | 6.55 | 240.12 | 16.76 | ---- | ---- | -+-----------+--------+--------+--------+--------+--------+--------+ -| Comments | | | completely bro- | -| | | | ken, monitor | -| | | | switches off | -+-----------+-----------------+-----------------+-----------------+ - - -+-----------+-----------------------------------------------------+ -| | accelerated | -| TRIDENTFB +-----------------+-----------------+-----------------+ -| of 2.6.12 | 8 bpp | 16 bpp | 32 bpp | -| | noypan | ypan | noypan | ypan | noypan | ypan | -+-----------+--------+--------+--------+--------+--------+--------+ -| Test 1 | ---- | ---- | 20.62 | 1.22 | ---- | ---- | -| Test 2 | ---- | ---- | 22.61 | 3.19 | ---- | ---- | -| Test 3 | ---- | ---- | 24.59 | 5.16 | ---- | ---- | -+-----------+--------+--------+--------+--------+--------+--------+ -| Comments | broken, writing | broken, ok only | completely bro- | -| | to wrong places | if bgcolor is | ken, monitor | -| | on screen + bug | black, bug in | switches off | -| | in fillrect() | fillrect() | | -+-----------+-----------------+-----------------+-----------------+ - - -+-----------+-----------------------------------------------------+ -| | not accelerated | -| VESAFB +-----------------+-----------------+-----------------+ -| of 2.6.12 | 8 bpp | 16 bpp | 32 bpp | -| | noypan | ypan | noypan | ypan | noypan | ypan | -+-----------+--------+--------+--------+--------+--------+--------+ -| Test 1 | 4.26 | 3.76 | 5.99 | 7.23 | ---- | ---- | -| Test 2 | 65.65 | 4.89 | 120.88 | 9.08 | ---- | ---- | -| Test 3 | 126.91 | 5.94 | 235.77 | 11.03 | ---- | ---- | -+-----------+--------+--------+--------+--------+--------+--------+ -| Comments | vga=0x307 | vga=0x31a | vga=0x31b not | -| | fh=80kHz | fh=80kHz | supported by | -| | fv=75kHz | fv=75kHz | video BIOS and | -| | | | hardware | -+-----------+-----------------+-----------------+-----------------+ - - -+-----------+-----------------------------------------------------+ -| | accelerated | -| CYBLAFB +-----------------+-----------------+-----------------+ -| | 8 bpp | 16 bpp | 32 bpp | -| | noypan | ypan | noypan | ypan | noypan | ypan | -+-----------+--------+--------+--------+--------+--------+--------+ -| Test 1 | 8.02 | 0.23 | 19.04 | 0.61 | 57.12 | 2.74 | -| Test 2 | 8.38 | 0.55 | 19.39 | 0.92 | 57.54 | 3.13 | -| Test 3 | 8.73 | 0.86 | 19.74 | 1.24 | 57.95 | 3.51 | -+-----------+--------+--------+--------+--------+--------+--------+ -| Comments | | | | -| | | | | -| | | | | -| | | | | -+-----------+-----------------+-----------------+-----------------+ diff --git a/Documentation/fb/cyblafb/todo b/Documentation/fb/cyblafb/todo deleted file mode 100644 index c5f6d0eae54..00000000000 --- a/Documentation/fb/cyblafb/todo +++ /dev/null @@ -1,31 +0,0 @@ -TODO / Missing features -======================= - -Verify LCD stuff "stretch" and "center" options are - completely untested ... this code needs to be - verified. As I don't have access to such - hardware, please contact me if you are - willing run some tests. - -Interlaced video modes The reason that interleaved - modes are disabled is that I do not know - the meaning of the vertical interlace - parameter. Also the datasheet mentions a - bit d8 of a horizontal interlace parameter, - but nowhere the lower 8 bits. Please help - if you can. - -low-res double scan modes Who needs it? - -accelerated color blitting Who needs it? The console driver does use color - blitting for nothing but drawing the penguine, - everything else is done using color expanding - blitting of 1bpp character bitmaps. - -ioctls Who needs it? - -TV-out Will be done later. Use "vga= " at boot time - to set a suitable video mode. - -??? Feel free to contact me if you have any - feature requests diff --git a/Documentation/fb/cyblafb/usage b/Documentation/fb/cyblafb/usage deleted file mode 100644 index a39bb3d402a..00000000000 --- a/Documentation/fb/cyblafb/usage +++ /dev/null @@ -1,217 +0,0 @@ -CyBlaFB is a framebuffer driver for the Cyberblade/i1 graphics core integrated -into the VIA Apollo PLE133 (aka vt8601) south bridge. It is developed and -tested using a VIA EPIA 5000 board. - -Cyblafb - compiled into the kernel or as a module? -================================================== - -You might compile cyblafb either as a module or compile it permanently into the -kernel. - -Unless you have a real reason to do so you should not compile both vesafb and -cyblafb permanently into the kernel. It's possible and it helps during the -developement cycle, but it's useless and will at least block some otherwise -usefull memory for ordinary users. - -Selecting Modes -=============== - - Startup Mode - ============ - - First of all, you might use the "vga=???" boot parameter as it is - documented in vesafb.txt and svga.txt. Cyblafb will detect the video - mode selected and will use the geometry and timings found by - inspecting the hardware registers. - - video=cyblafb vga=0x317 - - Alternatively you might use a combination of the mode, ref and bpp - parameters. If you compiled the driver into the kernel, add something - like this to the kernel command line: - - video=cyblafb:1280x1024,bpp=16,ref=50 ... - - If you compiled the driver as a module, the same mode would be - selected by the following command: - - modprobe cyblafb mode=1280x1024 bpp=16 ref=50 ... - - None of the modes possible to select as startup modes are affected by - the problems described at the end of the next subsection. - - For all startup modes cyblafb chooses a virtual x resolution of 2048, - the only exception is mode 1280x1024 in combination with 32 bpp. This - allows ywrap scrolling for all those modes if rotation is 0 or 2, and - also fast scrolling if rotation is 1 or 3. The default virtual y reso- - lution is 4096 for bpp == 8, 2048 for bpp==16 and 1024 for bpp == 32, - again with the only exception of 1280x1024 at 32 bpp. - - Please do set your video memory size to 8 Mb in the Bios setup. Other - values will work, but performace is decreased for a lot of modes. - - Mode changes using fbset - ======================== - - You might use fbset to change the video mode, see "man fbset". Cyblafb - generally does assume that you know what you are doing. But it does - some checks, especially those that are needed to prevent you from - damaging your hardware. - - - only 8, 16, 24 and 32 bpp video modes are accepted - - interlaced video modes are not accepted - - double scan video modes are not accepted - - if a flat panel is found, cyblafb does not allow you - to program a resolution higher than the physical - resolution of the flat panel monitor - - cyblafb does not allow vclk to exceed 230 MHz. As 32 bpp - and (currently) 24 bit modes use a doubled vclk internally, - the dotclock limit as seen by fbset is 115 MHz for those - modes and 230 MHz for 8 and 16 bpp modes. - - cyblafb will allow you to select very high resolutions as - long as the hardware can be programmed to these modes. The - documented limit 1600x1200 is not enforced, but don't expect - perfect signal quality. - - Any request that violates the rules given above will be either changed - to something the hardware supports or an error value will be returned. - - If you program a virtual y resolution higher than the hardware limit, - cyblafb will silently decrease that value to the highest possible - value. The same is true for a virtual x resolution that is not - supported by the hardware. Cyblafb tries to adapt vyres first because - vxres decides if ywrap scrolling is possible or not. - - Attempts to disable acceleration are ignored, I believe that this is - safe. - - Some video modes that should work do not work as expected. If you use - the standard fb.modes, fbset 640x480-60 will program that mode, but - you will see a vertical area, about two characters wide, with only - much darker characters than the other characters on the screen. - Cyblafb does allow that mode to be set, as it does not violate the - official specifications. It would need a lot of code to reliably sort - out all invalid modes, playing around with the margin values will - give a valid mode quickly. And if cyblafb would detect such an invalid - mode, should it silently alter the requested values or should it - report an error? Both options have some pros and cons. As stated - above, none of the startup modes are affected, and if you set - verbosity to 1 or higher, cyblafb will print the fbset command that - would be needed to program that mode using fbset. - - -Other Parameters -================ - - -crt don't autodetect, assume monitor connected to - standard VGA connector - -fp don't autodetect, assume flat panel display - connected to flat panel monitor interface - -nativex inform driver about native x resolution of - flat panel monitor connected to special - interface (should be autodetected) - -stretch stretch image to adapt low resolution modes to - higer resolutions of flat panel monitors - connected to special interface - -center center image to adapt low resolution modes to - higer resolutions of flat panel monitors - connected to special interface - -memsize use if autodetected memsize is wrong ... - should never be necessary - -nopcirr disable PCI read retry -nopciwr disable PCI write retry -nopcirb disable PCI read bursts -nopciwb disable PCI write bursts - -bpp bpp for specified modes - valid values: 8 || 16 || 24 || 32 - -ref refresh rate for specified mode - valid values: 50 <= ref <= 85 - -mode 640x480 or 800x600 or 1024x768 or 1280x1024 - if not specified, the startup mode will be detected - and used, so you might also use the vga=??? parameter - described in vesafb.txt. If you do not specify a mode, - bpp and ref parameters are ignored. - -verbosity 0 is the default, increase to at least 2 for every - bug report! - -Development hints -================= - -It's much faster do compile a module and to load the new version after -unloading the old module than to compile a new kernel and to reboot. So if you -try to work on cyblafb, it might be a good idea to use cyblafb as a module. -In real life, fast often means dangerous, and that's also the case here. If -you introduce a serious bug when cyblafb is compiled into the kernel, the -kernel will lock or oops with a high probability before the file system is -mounted, and the danger for your data is low. If you load a broken own version -of cyblafb on a running system, the danger for the integrity of the file -system is much higher as you might need a hard reset afterwards. Decide -yourself. - -Module unloading, the vfb method -================================ - -If you want to unload/reload cyblafb using the virtual framebuffer, you need -to enable vfb support in the kernel first. After that, load the modules as -shown below: - - modprobe vfb vfb_enable=1 - modprobe fbcon - modprobe cyblafb - fbset -fb /dev/fb1 1280x1024-60 -vyres 2662 - con2fb /dev/fb1 /dev/tty1 - ... - -If you now made some changes to cyblafb and want to reload it, you might do it -as show below: - - con2fb /dev/fb0 /dev/tty1 - ... - rmmod cyblafb - modprobe cyblafb - con2fb /dev/fb1 /dev/tty1 - ... - -Of course, you might choose another mode, and most certainly you also want to -map some other /dev/tty* to the real framebuffer device. You might also choose -to compile fbcon as a kernel module or place it permanently in the kernel. - -I do not know of any way to unload fbcon, and fbcon will prevent the -framebuffer device loaded first from unloading. [If there is a way, then -please add a description here!] - -Module unloading, the vesafb method -=================================== - -Configure the kernel: - - <*> Support for frame buffer devices - [*] VESA VGA graphics support - Cyberblade/i1 support - -Add e.g. "video=vesafb:ypan vga=0x307" to the kernel parameters. The ypan -parameter is important, choose any vga parameter you like as long as it is -a graphics mode. - -After booting, load cyblafb without any mode and bpp parameter and assign -cyblafb to individual ttys using con2fb, e.g.: - - modprobe cyblafb - con2fb /dev/fb1 /dev/tty1 - -Unloading cyblafb works without problems after you assign vesafb to all -ttys again, e.g.: - - con2fb /dev/fb0 /dev/tty1 - rmmod cyblafb diff --git a/Documentation/fb/cyblafb/whatsnew b/Documentation/fb/cyblafb/whatsnew deleted file mode 100644 index 76c07a26e04..00000000000 --- a/Documentation/fb/cyblafb/whatsnew +++ /dev/null @@ -1,29 +0,0 @@ -0.62 -==== - - - the vesafb parameter has been removed as I decided to allow the - feature without any special parameter. - - - Cyblafb does not use the vga style of panning any longer, now the - "right view" register in the graphics engine IO space is used. Without - that change it was impossible to use all available memory, and without - access to all available memory it is impossible to ywrap. - - - The imageblit function now uses hardware acceleration for all font - widths. Hardware blitting across pixel column 2048 is broken in the - cyberblade/i1 graphics core, but we work around that hardware bug. - - - modes with vxres != xres are supported now. - - - ywrap scrolling is supported now and the default. This is a big - performance gain. - - - default video modes use vyres > yres and vxres > xres to allow - almost optimal scrolling speed for normal and rotated screens - - - some features mainly usefull for debugging the upper layers of the - framebuffer system have been added, have a look at the code - - - fixed: Oops after unloading cyblafb when reading /proc/io* - - - we work around some bugs of the higher framebuffer layers. diff --git a/Documentation/fb/cyblafb/whycyblafb b/Documentation/fb/cyblafb/whycyblafb deleted file mode 100644 index a123bc11e69..00000000000 --- a/Documentation/fb/cyblafb/whycyblafb +++ /dev/null @@ -1,85 +0,0 @@ -I tried the following framebuffer drivers: - - - TRIDENTFB is full of bugs. Acceleration is broken for Blade3D - graphics cores like the cyberblade/i1. It claims to support a great - number of devices, but documentation for most of these devices is - unfortunately not available. There is _no_ reason to use tridentfb - for cyberblade/i1 + CRT users. VESAFB is faster, and the one - advantage, mode switching, is broken in tridentfb. - - - VESAFB is used by many distributions as a standard. Vesafb does - not support mode switching. VESAFB is a bit faster than the working - configurations of TRIDENTFB, but it is still too slow, even if you - use ypan. - - - EPIAFB (you'll find it on sourceforge) supports the Cyberblade/i1 - graphics core, but it still has serious bugs and developement seems - to have stopped. This is the one driver with TV-out support. If you - do need this feature, try epiafb. - -None of these drivers was a real option for me. - -I believe that is unreasonable to change code that announces to support 20 -devices if I only have more or less sufficient documentation for exactly one -of these. The risk of breaking device foo while fixing device bar is too high. - -So I decided to start CyBlaFB as a stripped down tridentfb. - -All code specific to other Trident chips has been removed. After that there -were a lot of cosmetic changes to increase the readability of the code. All -register names were changed to those mnemonics used in the datasheet. Function -and macro names were changed if they hindered easy understanding of the code. - -After that I debugged the code and implemented some new features. I'll try to -give a little summary of the main changes: - - - calculation of vertical and horizontal timings was fixed - - - video signal quality has been improved dramatically - - - acceleration: - - - fillrect and copyarea were fixed and reenabled - - - color expanding imageblit was newly implemented, color - imageblit (only used to draw the penguine) still uses the - generic code. - - - init of the acceleration engine was improved and moved to a - place where it really works ... - - - sync function has a timeout now and tries to reset and - reinit the accel engine if necessary - - - fewer slow copyarea calls when doing ypan scrolling by using - undocumented bit d21 of screen start address stored in - CR2B[5]. BIOS does use it also, so this should be safe. - - - cyblafb rejects any attempt to set modes that would cause vclk - values above reasonable 230 MHz. 32bit modes use a clock - multiplicator of 2, so fbset does show the correct values for - pixclock but not for vclk in this case. The fbset limit is 115 MHz - for 32 bpp modes. - - - cyblafb rejects modes known to be broken or unimplemented (all - interlaced modes, all doublescan modes for now) - - - cyblafb now works independant of the video mode in effect at startup - time (tridentfb does not init all needed registers to reasonable - values) - - - switching between video modes does work reliably now - - - the first video mode now is the one selected on startup using the - vga=???? mechanism or any of - - 640x480, 800x600, 1024x768, 1280x1024 - - 8, 16, 24 or 32 bpp - - refresh between 50 Hz and 85 Hz, 1 Hz steps (1280x1024-32 - is limited to 63Hz) - - - pci retry and pci burst mode are settable (try to disable if you - experience latency problems) - - - built as a module cyblafb might be unloaded and reloaded using - the vfb module and con2vt or might be used together with vesafb - -- cgit v1.2.3 From 01a24d2b9309676ec2e7069cd19f5b1c4a1505e0 Mon Sep 17 00:00:00 2001 From: Paulius Zaleckas Date: Tue, 31 Mar 2009 13:55:44 +0100 Subject: [ARM] 5437/1: Add documentation for "nohlt" kernel parameter As per discussion in: http://marc.info/?l=linux-arm-kernel&m=123633652517391&w=2 Signed-off-by: Paulius Zaleckas Acked-by: Paul Mundt Signed-off-by: Russell King --- Documentation/kernel-parameters.txt | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index be3bde51b56..73fa52c0df2 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1513,7 +1513,9 @@ and is between 256 and 4096 characters. It is defined in the file noclflush [BUGS=X86] Don't use the CLFLUSH instruction - nohlt [BUGS=ARM,SH] + nohlt [BUGS=ARM,SH] Tells the kernel that the sleep(SH) or + wfi(ARM) instruction doesn't work correctly and not to + use it. This is also useful when using JTAG debugger. no-hlt [BUGS=X86-32] Tells the kernel that the hlt instruction doesn't work correctly and not to -- cgit v1.2.3 From 5adfb64bdd4eee07e0677cbad12a2f80fecc6715 Mon Sep 17 00:00:00 2001 From: Ramkrishna Vepa Date: Wed, 1 Apr 2009 18:14:23 +0000 Subject: Neterion: Driver help file - vxge driver help text file. - No change from previous submission. - Changes in previous submissions - Removed the performance tuning section with instructions to disable time stamps and change sysctl settings - Reported by Dave Miller General clean up. - Removed tx/rx_pause, exec_mode, tx_steering_type, rx_steering_type, gro, intr_type, rx & tx max_indicate_pkts and exec_mode loadable parameters. The driver default settings work well in most if not all cases. Another patch to configure these parameters with ethtool will be released in the future - Reported by Stephen Hemminger. - Incorporated following fixes based on comments from Ben Hutchings Removed references to earlier kernel versions. Removed sections that are similar for all drivers - Load/Unload Identifying the adapter/interface Boot time configuration Removed loadable parameter - NAPI - Napi is always enabled. rx_steering_type & ring_blocks - The driver default settings work well in most if not all cases. Another patch to configure these parameters with ethtool will be released in the future. Removed ethtool support section - No need to duplicate ethtool docs here. Removed Known Issue on SUSE 9 - Doesn't apply when using a current kernel. Removed Common Problems section - These don't apply to in-tree modules. Removed Available Downloads section - Not sure this belongs in-tree. Removed Copyright information - This notice doesn't belong in the kernel. Signed-off-by: Sivakumar Subramani Signed-off-by: Rastapur Santosh Signed-off-by: Ramkrishna Vepa Signed-off-by: David S. Miller --- Documentation/networking/vxge.txt | 100 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 100 insertions(+) create mode 100644 Documentation/networking/vxge.txt (limited to 'Documentation') diff --git a/Documentation/networking/vxge.txt b/Documentation/networking/vxge.txt new file mode 100644 index 00000000000..d2e2997e6fa --- /dev/null +++ b/Documentation/networking/vxge.txt @@ -0,0 +1,100 @@ +Neterion's (Formerly S2io) X3100 Series 10GbE PCIe Server Adapter Linux driver +============================================================================== + +Contents +-------- + +1) Introduction +2) Features supported +3) Configurable driver parameters +4) Troubleshooting + +1) Introduction: +---------------- +This Linux driver supports all Neterion's X3100 series 10 GbE PCIe I/O +Virtualized Server adapters. +The X3100 series supports four modes of operation, configurable via +firmware - + Single function mode + Multi function mode + SRIOV mode + MRIOV mode +The functions share a 10GbE link and the pci-e bus, but hardly anything else +inside the ASIC. Features like independent hw reset, statistics, bandwidth/ +priority allocation and guarantees, GRO, TSO, interrupt moderation etc are +supported independently on each function. + +(See below for a complete list of features supported for both IPv4 and IPv6) + +2) Features supported: +---------------------- + +i) Single function mode (up to 17 queues) + +ii) Multi function mode (up to 17 functions) + +iii) PCI-SIG's I/O Virtualization + - Single Root mode: v1.0 (up to 17 functions) + - Multi-Root mode: v1.0 (up to 17 functions) + +iv) Jumbo frames + X3100 Series supports MTU up to 9600 bytes, modifiable using + ifconfig command. + +v) Offloads supported: (Enabled by default) + Checksum offload (TCP/UDP/IP) on transmit and receive paths + TCP Segmentation Offload (TSO) on transmit path + Generic Receive Offload (GRO) on receive path + +vi) MSI-X: (Enabled by default) + Resulting in noticeable performance improvement (up to 7% on certain + platforms). + +vii) NAPI: (Enabled by default) + For better Rx interrupt moderation. + +viii)RTH (Receive Traffic Hash): (Enabled by default) + Receive side steering for better scaling. + +ix) Statistics + Comprehensive MAC-level and software statistics displayed using + "ethtool -S" option. + +x) Multiple hardware queues: (Enabled by default) + Up to 17 hardware based transmit and receive data channels, with + multiple steering options (transmit multiqueue enabled by default). + +3) Configurable driver parameters: +---------------------------------- + +i) max_config_dev + Specifies maximum device functions to be enabled. + Valid range: 1-8 + +ii) max_config_port + Specifies number of ports to be enabled. + Valid range: 1,2 + Default: 1 + +iii)max_config_vpath + Specifies maximum VPATH(s) configured for each device function. + Valid range: 1-17 + +iv) vlan_tag_strip + Enables/disables vlan tag stripping from all received tagged frames that + are not replicated at the internal L2 switch. + Valid range: 0,1 (disabled, enabled respectively) + Default: 1 + +v) addr_learn_en + Enable learning the mac address of the guest OS interface in + virtualization environment. + Valid range: 0,1 (disabled, enabled respectively) + Default: 0 + +4) Troubleshooting: +------------------- + +To resolve an issue with the source code or X3100 series adapter, please collect +the statistics, register dumps using ethool, relevant logs and email them to +support@neterion.com. -- cgit v1.2.3 From 9ba30d74446dd0629d797ecd038379725d351bc6 Mon Sep 17 00:00:00 2001 From: Jesper Dangaard Brouer Date: Sun, 29 Mar 2009 23:02:56 +0000 Subject: Doc: Fix missing whitespaces in RCU documentation. Trivial fix while reading through the RCU docs. Reviewed-by: Paul E. McKenney Signed-off-by: Jesper Dangaard Brouer Signed-off-by: David S. Miller --- Documentation/RCU/rcu.txt | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/RCU/rcu.txt b/Documentation/RCU/rcu.txt index 95821a29ae4..7aa2002ade7 100644 --- a/Documentation/RCU/rcu.txt +++ b/Documentation/RCU/rcu.txt @@ -81,7 +81,7 @@ o I hear that RCU needs work in order to support realtime kernels? This work is largely completed. Realtime-friendly RCU can be enabled via the CONFIG_PREEMPT_RCU kernel configuration parameter. However, work is in progress for enabling priority boosting of - preempted RCU read-side critical sections.This is needed if you + preempted RCU read-side critical sections. This is needed if you have CPU-bound realtime threads. o Where can I find more information on RCU? -- cgit v1.2.3 From 3943ac5d99ec024f97442e5f3def1034bb0b1bb0 Mon Sep 17 00:00:00 2001 From: Jesper Dangaard Brouer Date: Sun, 29 Mar 2009 23:03:01 +0000 Subject: Doc: Fix wrong API example usage of call_rcu(). At some point the API of call_rcu() changed from three parameters to two parameters, correct the documentation. One confusing thing in RCU/listRCU.txt, which is NOT fixed in this patch, is that no reason or explaination is given for using call_rcu() instead of the normal synchronize_rcu() call. Reviewed-by: Paul E. McKenney Signed-off-by: Jesper Dangaard Brouer Signed-off-by: David S. Miller --- Documentation/RCU/listRCU.txt | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'Documentation') diff --git a/Documentation/RCU/listRCU.txt b/Documentation/RCU/listRCU.txt index 1fd175368a8..4349c1487e9 100644 --- a/Documentation/RCU/listRCU.txt +++ b/Documentation/RCU/listRCU.txt @@ -118,7 +118,7 @@ Following are the RCU equivalents for these two functions: list_for_each_entry(e, list, list) { if (!audit_compare_rule(rule, &e->rule)) { list_del_rcu(&e->list); - call_rcu(&e->rcu, audit_free_rule, e); + call_rcu(&e->rcu, audit_free_rule); return 0; } } @@ -206,7 +206,7 @@ RCU ("read-copy update") its name. The RCU code is as follows: ne->rule.action = newaction; ne->rule.file_count = newfield_count; list_replace_rcu(e, ne); - call_rcu(&e->rcu, audit_free_rule, e); + call_rcu(&e->rcu, audit_free_rule); return 0; } } @@ -283,7 +283,7 @@ flag under the spinlock as follows: list_del_rcu(&e->list); e->deleted = 1; spin_unlock(&e->lock); - call_rcu(&e->rcu, audit_free_rule, e); + call_rcu(&e->rcu, audit_free_rule); return 0; } } -- cgit v1.2.3 From edd4070f5d943b35e3e1a2e5e95e4a2eebb11d53 Mon Sep 17 00:00:00 2001 From: Jesper Dangaard Brouer Date: Tue, 31 Mar 2009 09:36:48 +0000 Subject: Doc: Fix spelling in RCU/rculist_nulls.txt. Doc: Fix spelling in RCU/rculist_nulls.txt. Trival spelling fixes in RCU/rculist_nulls.txt. Reviewed-by: Paul E. McKenney Signed-off-by: Jesper Dangaard Brouer Tested-by: Jarek Poplawski Signed-off-by: David S. Miller --- Documentation/RCU/rculist_nulls.txt | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'Documentation') diff --git a/Documentation/RCU/rculist_nulls.txt b/Documentation/RCU/rculist_nulls.txt index 239f542d48b..6389dec3345 100644 --- a/Documentation/RCU/rculist_nulls.txt +++ b/Documentation/RCU/rculist_nulls.txt @@ -21,7 +21,7 @@ if (obj) { /* * Because a writer could delete object, and a writer could * reuse these object before the RCU grace period, we - * must check key after geting the reference on object + * must check key after getting the reference on object */ if (obj->key != key) { // not the object we expected put_ref(obj); @@ -117,7 +117,7 @@ a race (some writer did a delete and/or a move of an object to another chain) checking the final 'nulls' value if the lookup met the end of chain. If final 'nulls' value is not the slot number, then we must restart the lookup at -the begining. If the object was moved to same chain, +the beginning. If the object was moved to the same chain, then the reader doesnt care : It might eventually scan the list again without harm. -- cgit v1.2.3 From 7ac9bcd5da59dd96eb1153d3fc04c3471fa5c09d Mon Sep 17 00:00:00 2001 From: Marcin Slusarz Date: Sun, 16 Nov 2008 20:52:19 +0100 Subject: udf: implement mode and dmode mounting options "dmode" allows overriding permissions of directories and "mode" allows overriding permissions of files. Signed-off-by: Marcin Slusarz Cc: Jan Kara Signed-off-by: Jan Kara --- Documentation/filesystems/udf.txt | 2 ++ 1 file changed, 2 insertions(+) (limited to 'Documentation') diff --git a/Documentation/filesystems/udf.txt b/Documentation/filesystems/udf.txt index fde829a756e..902b95d0ee5 100644 --- a/Documentation/filesystems/udf.txt +++ b/Documentation/filesystems/udf.txt @@ -24,6 +24,8 @@ The following mount options are supported: gid= Set the default group. umask= Set the default umask. + mode= Set the default file permissions. + dmode= Set the default directory permissions. uid= Set the default user. bs= Set the block size. unhide Show otherwise hidden files. -- cgit v1.2.3 From 8a0cecffeb52363a57257bbbbd58f4c4537a75bb Mon Sep 17 00:00:00 2001 From: David Brownell Date: Thu, 2 Apr 2009 16:57:06 -0700 Subject: gpio: gpio_{request,free}() now required (feature removal) We want to phase out the GPIO "autorequest" mechanism in gpiolib and require all callers to use gpio_request(). - Update feature-removal-schedule - Update the documentation now - Convert the relevant pr_warning() in gpiolib to a WARN() so folk using this mechanism get a noisy stack dump Some drivers and board init code will probably need to change. Implementations not using gpiolib will still be fine; they are already required to implement gpio_{request,free}() stubs. Signed-off-by: David Brownell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/feature-removal-schedule.txt | 10 ++++++++++ Documentation/gpio.txt | 23 +++++++++-------------- 2 files changed, 19 insertions(+), 14 deletions(-) (limited to 'Documentation') diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index d0f35467064..a23361e80c6 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -255,6 +255,16 @@ Who: Jan Engelhardt --------------------------- +What: GPIO autorequest on gpio_direction_{input,output}() in gpiolib +When: February 2010 +Why: All callers should use explicit gpio_request()/gpio_free(). + The autorequest mechanism in gpiolib was provided mostly as a + migration aid for legacy GPIO interfaces (for SOC based GPIOs). + Those users have now largely migrated. Platforms implementing + the GPIO interfaces without using gpiolib will see no changes. +Who: David Brownell +--------------------------- + What: b43 support for firmware revision < 410 When: The schedule was July 2008, but it was decided that we are going to keep the code as long as there are no major maintanance headaches. diff --git a/Documentation/gpio.txt b/Documentation/gpio.txt index b1b98870124..145c25a170c 100644 --- a/Documentation/gpio.txt +++ b/Documentation/gpio.txt @@ -123,7 +123,10 @@ platform-specific implementation issue. Using GPIOs ----------- -One of the first things to do with a GPIO, often in board setup code when +The first thing a system should do with a GPIO is allocate it, using +the gpio_request() call; see later. + +One of the next things to do with a GPIO, often in board setup code when setting up a platform_device using the GPIO, is mark its direction: /* set as input or output, returning 0 or negative errno */ @@ -141,8 +144,8 @@ This helps avoid signal glitching during system startup. For compatibility with legacy interfaces to GPIOs, setting the direction of a GPIO implicitly requests that GPIO (see below) if it has not been -requested already. That compatibility may be removed in the future; -explicitly requesting GPIOs is strongly preferred. +requested already. That compatibility is being removed from the optional +gpiolib framework. Setting the direction can fail if the GPIO number is invalid, or when that particular GPIO can't be used in that mode. It's generally a bad @@ -195,7 +198,7 @@ This requires sleeping, which can't be done from inside IRQ handlers. Platforms that support this type of GPIO distinguish them from other GPIOs by returning nonzero from this call (which requires a valid GPIO number, -either explicitly or implicitly requested): +which should have been previously allocated with gpio_request): int gpio_cansleep(unsigned gpio); @@ -212,10 +215,9 @@ for GPIOs that can't be accessed from IRQ handlers, these calls act the same as the spinlock-safe calls. -Claiming and Releasing GPIOs (OPTIONAL) ---------------------------------------- +Claiming and Releasing GPIOs +---------------------------- To help catch system configuration errors, two calls are defined. -However, many platforms don't currently support this mechanism. /* request GPIO, returning 0 or negative errno. * non-null labels may be useful for diagnostics. @@ -244,13 +246,6 @@ Some platforms may also use knowledge about what GPIOs are active for power management, such as by powering down unused chip sectors and, more easily, gating off unused clocks. -These two calls are optional because not not all current Linux platforms -offer such functionality in their GPIO support; a valid implementation -could return success for all gpio_request() calls. Unlike the other calls, -the state they represent doesn't normally match anything from a hardware -register; it's just a software bitmap which clearly is not necessary for -correct operation of hardware or (bug free) drivers. - Note that requesting a GPIO does NOT cause it to be configured in any way; it just marks that GPIO as in use. Separate code must handle any pin setup (e.g. controlling which pin the GPIO uses, pullup/pulldown). -- cgit v1.2.3 From 70eed8d06601ca3810a0e56035eae6496d57856b Mon Sep 17 00:00:00 2001 From: Henrik Austad Date: Thu, 2 Apr 2009 16:57:18 -0700 Subject: documentation: ignore byproducts from latex When using 'make pdfdocs', auto-generated files should be ignored Signed-off-by: Henrik Austad Cc: Randy Dunlap Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/DocBook/.gitignore | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'Documentation') diff --git a/Documentation/DocBook/.gitignore b/Documentation/DocBook/.gitignore index c102c02ecf8..c6def352fe3 100644 --- a/Documentation/DocBook/.gitignore +++ b/Documentation/DocBook/.gitignore @@ -4,3 +4,7 @@ *.html *.9.gz *.9 +*.aux +*.dvi +*.log +*.out -- cgit v1.2.3 From 760df93ecdd59fc1c213a491b5adee79f53606da Mon Sep 17 00:00:00 2001 From: Shen Feng Date: Thu, 2 Apr 2009 16:57:20 -0700 Subject: documentation: update Documentation/filesystem/proc.txt and Documentation/sysctls Now /proc/sys is described in many places and much information is redundant. This patch updates the proc.txt and move the /proc/sys desciption out to the files in Documentation/sysctls. Details are: merge - 2.1 /proc/sys/fs - File system data - 2.11 /proc/sys/fs/mqueue - POSIX message queues filesystem - 2.17 /proc/sys/fs/epoll - Configuration options for the epoll interface with Documentation/sysctls/fs.txt. remove - 2.2 /proc/sys/fs/binfmt_misc - Miscellaneous binary formats since it's not better then the Documentation/binfmt_misc.txt. merge - 2.3 /proc/sys/kernel - general kernel parameters with Documentation/sysctls/kernel.txt remove - 2.5 /proc/sys/dev - Device specific parameters since it's obsolete the sysfs is used now. remove - 2.6 /proc/sys/sunrpc - Remote procedure calls since it's not better then the Documentation/sysctls/sunrpc.txt move - 2.7 /proc/sys/net - Networking stuff - 2.9 Appletalk - 2.10 IPX to newly created Documentation/sysctls/net.txt. remove - 2.8 /proc/sys/net/ipv4 - IPV4 settings since it's not better then the Documentation/networking/ip-sysctl.txt. add - Chapter 3 Per-Process Parameters to descibe /proc//xxx parameters. Signed-off-by: Shen Feng Cc: Randy Dunlap Cc: "David S. Miller" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/filesystems/proc.txt | 1097 +----------------------------------- Documentation/sysctl/00-INDEX | 2 + Documentation/sysctl/fs.txt | 74 ++- Documentation/sysctl/kernel.txt | 53 ++ Documentation/sysctl/net.txt | 174 ++++++ 5 files changed, 329 insertions(+), 1071 deletions(-) create mode 100644 Documentation/sysctl/net.txt (limited to 'Documentation') diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index efc4fd9f40c..ce84cfc9eae 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -5,6 +5,7 @@ Bodo Bauer 2.4.x update Jorge Nerin November 14 2000 +move /proc/sys Shen Feng April 1 2009 ------------------------------------------------------------------------------ Version 1.3 Kernel version 2.2.12 Kernel version 2.4.0-test11-pre4 @@ -26,25 +27,17 @@ Table of Contents 1.6 Parallel port info in /proc/parport 1.7 TTY info in /proc/tty 1.8 Miscellaneous kernel statistics in /proc/stat + 1.9 Ext4 file system parameters 2 Modifying System Parameters - 2.1 /proc/sys/fs - File system data - 2.2 /proc/sys/fs/binfmt_misc - Miscellaneous binary formats - 2.3 /proc/sys/kernel - general kernel parameters - 2.4 /proc/sys/vm - The virtual memory subsystem - 2.5 /proc/sys/dev - Device specific parameters - 2.6 /proc/sys/sunrpc - Remote procedure calls - 2.7 /proc/sys/net - Networking stuff - 2.8 /proc/sys/net/ipv4 - IPV4 settings - 2.9 Appletalk - 2.10 IPX - 2.11 /proc/sys/fs/mqueue - POSIX message queues filesystem - 2.12 /proc//oom_adj - Adjust the oom-killer score - 2.13 /proc//oom_score - Display current oom-killer score - 2.14 /proc//io - Display the IO accounting fields - 2.15 /proc//coredump_filter - Core dump filtering settings - 2.16 /proc//mountinfo - Information about mounts - 2.17 /proc/sys/fs/epoll - Configuration options for the epoll interface + + 3 Per-Process Parameters + 3.1 /proc//oom_adj - Adjust the oom-killer score + 3.2 /proc//oom_score - Display current oom-killer score + 3.3 /proc//io - Display the IO accounting fields + 3.4 /proc//coredump_filter - Core dump filtering settings + 3.5 /proc//mountinfo - Information about mounts + ------------------------------------------------------------------------------ Preface @@ -990,1021 +983,24 @@ review the kernel documentation in the directory /usr/src/linux/Documentation. This chapter is heavily based on the documentation included in the pre 2.2 kernels, and became part of it in version 2.2.1 of the Linux kernel. -2.1 /proc/sys/fs - File system data ------------------------------------ - -This subdirectory contains specific file system, file handle, inode, dentry -and quota information. - -Currently, these files are in /proc/sys/fs: - -dentry-state ------------- - -Status of the directory cache. Since directory entries are dynamically -allocated and deallocated, this file indicates the current status. It holds -six values, in which the last two are not used and are always zero. The others -are listed in table 2-1. - - -Table 2-1: Status files of the directory cache -.............................................................................. - File Content - nr_dentry Almost always zero - nr_unused Number of unused cache entries - age_limit - in seconds after the entry may be reclaimed, when memory is short - want_pages internally -.............................................................................. - -dquot-nr and dquot-max ----------------------- - -The file dquot-max shows the maximum number of cached disk quota entries. - -The file dquot-nr shows the number of allocated disk quota entries and the -number of free disk quota entries. - -If the number of available cached disk quotas is very low and you have a large -number of simultaneous system users, you might want to raise the limit. - -file-nr and file-max --------------------- - -The kernel allocates file handles dynamically, but doesn't free them again at -this time. - -The value in file-max denotes the maximum number of file handles that the -Linux kernel will allocate. When you get a lot of error messages about running -out of file handles, you might want to raise this limit. The default value is -10% of RAM in kilobytes. To change it, just write the new number into the -file: - - # cat /proc/sys/fs/file-max - 4096 - # echo 8192 > /proc/sys/fs/file-max - # cat /proc/sys/fs/file-max - 8192 - - -This method of revision is useful for all customizable parameters of the -kernel - simply echo the new value to the corresponding file. - -Historically, the three values in file-nr denoted the number of allocated file -handles, the number of allocated but unused file handles, and the maximum -number of file handles. Linux 2.6 always reports 0 as the number of free file -handles -- this is not an error, it just means that the number of allocated -file handles exactly matches the number of used file handles. - -Attempts to allocate more file descriptors than file-max are reported with -printk, look for "VFS: file-max limit reached". - -inode-state and inode-nr ------------------------- - -The file inode-nr contains the first two items from inode-state, so we'll skip -to that file... - -inode-state contains two actual numbers and five dummy values. The numbers -are nr_inodes and nr_free_inodes (in order of appearance). - -nr_inodes -~~~~~~~~~ - -Denotes the number of inodes the system has allocated. This number will -grow and shrink dynamically. - -nr_open -------- - -Denotes the maximum number of file-handles a process can -allocate. Default value is 1024*1024 (1048576) which should be -enough for most machines. Actual limit depends on RLIMIT_NOFILE -resource limit. - -nr_free_inodes --------------- - -Represents the number of free inodes. Ie. The number of inuse inodes is -(nr_inodes - nr_free_inodes). - -aio-nr and aio-max-nr ---------------------- - -aio-nr is the running total of the number of events specified on the -io_setup system call for all currently active aio contexts. If aio-nr -reaches aio-max-nr then io_setup will fail with EAGAIN. Note that -raising aio-max-nr does not result in the pre-allocation or re-sizing -of any kernel data structures. - -2.2 /proc/sys/fs/binfmt_misc - Miscellaneous binary formats ------------------------------------------------------------ - -Besides these files, there is the subdirectory /proc/sys/fs/binfmt_misc. This -handles the kernel support for miscellaneous binary formats. - -Binfmt_misc provides the ability to register additional binary formats to the -Kernel without compiling an additional module/kernel. Therefore, binfmt_misc -needs to know magic numbers at the beginning or the filename extension of the -binary. - -It works by maintaining a linked list of structs that contain a description of -a binary format, including a magic with size (or the filename extension), -offset and mask, and the interpreter name. On request it invokes the given -interpreter with the original program as argument, as binfmt_java and -binfmt_em86 and binfmt_mz do. Since binfmt_misc does not define any default -binary-formats, you have to register an additional binary-format. - -There are two general files in binfmt_misc and one file per registered format. -The two general files are register and status. - -Registering a new binary format -------------------------------- - -To register a new binary format you have to issue the command - - echo :name:type:offset:magic:mask:interpreter: > /proc/sys/fs/binfmt_misc/register - - - -with appropriate name (the name for the /proc-dir entry), offset (defaults to -0, if omitted), magic, mask (which can be omitted, defaults to all 0xff) and -last but not least, the interpreter that is to be invoked (for example and -testing /bin/echo). Type can be M for usual magic matching or E for filename -extension matching (give extension in place of magic). - -Check or reset the status of the binary format handler ------------------------------------------------------- - -If you do a cat on the file /proc/sys/fs/binfmt_misc/status, you will get the -current status (enabled/disabled) of binfmt_misc. Change the status by echoing -0 (disables) or 1 (enables) or -1 (caution: this clears all previously -registered binary formats) to status. For example echo 0 > status to disable -binfmt_misc (temporarily). - -Status of a single handler --------------------------- - -Each registered handler has an entry in /proc/sys/fs/binfmt_misc. These files -perform the same function as status, but their scope is limited to the actual -binary format. By cating this file, you also receive all related information -about the interpreter/magic of the binfmt. - -Example usage of binfmt_misc (emulate binfmt_java) --------------------------------------------------- - - cd /proc/sys/fs/binfmt_misc - echo ':Java:M::\xca\xfe\xba\xbe::/usr/local/java/bin/javawrapper:' > register - echo ':HTML:E::html::/usr/local/java/bin/appletviewer:' > register - echo ':Applet:M::| CacheFS | +---------+ | +----------+ | | /dev/hda5 | | | | | +--------------+ +---------+ +-->| | | | | | |--+ | AFS |----->| FS-Cache | | | | |--+ +---------+ +-->| | | | | | | +--------------+ +---------+ | +----------+ | | | | | | +-->| CacheFiles | | ISOFS |--+ | /var/cache | | | +--------------+ +---------+ General documentation and documentation of the netfs specific API are provided in addition to the header files. As this patch stands, it is possible to build a filesystem against the facility and attempt to use it. All that will happen is that all requests will be immediately denied as if no cache is present. Further patches will implement the core of the facility. The facility will transfer requests from networking filesystems to appropriate caches if possible, or else gracefully deny them. If this facility is disabled in the kernel configuration, then all its operations will trivially reduce to nothing during compilation. WHY NOT I_MAPPING? ================== I have added my own API to implement caching rather than using i_mapping to do this for a number of reasons. These have been discussed a lot on the LKML and CacheFS mailing lists, but to summarise the basics: (1) Most filesystems don't do hole reportage. Holes in files are treated as blocks of zeros and can't be distinguished otherwise, making it difficult to distinguish blocks that have been read from the network and cached from those that haven't. (2) The backing inode must be fully populated before being exposed to userspace through the main inode because the VM/VFS goes directly to the backing inode and does not interrogate the front inode's VM ops. Therefore: (a) The backing inode must fit entirely within the cache. (b) All backed files currently open must fit entirely within the cache at the same time. (c) A working set of files in total larger than the cache may not be cached. (d) A file may not grow larger than the available space in the cache. (e) A file that's open and cached, and remotely grows larger than the cache is potentially stuffed. (3) Writes go to the backing filesystem, and can only be transferred to the network when the file is closed. (4) There's no record of what changes have been made, so the whole file must be written back. (5) The pages belong to the backing filesystem, and all metadata associated with that page are relevant only to the backing filesystem, and not anything stacked atop it. OVERVIEW ======== FS-Cache provides (or will provide) the following facilities: (1) Caches can be added / removed at any time, even whilst in use. (2) Adds a facility by which tags can be used to refer to caches, even if they're not available yet. (3) More than one cache can be used at once. Caches can be selected explicitly by use of tags. (4) The netfs is provided with an interface that allows either party to withdraw caching facilities from a file (required for (1)). (5) A netfs may annotate cache objects that belongs to it. This permits the storage of coherency maintenance data. (6) Cache objects will be pinnable and space reservations will be possible. (7) The interface to the netfs returns as few errors as possible, preferring rather to let the netfs remain oblivious. (8) Cookies are used to represent indices, files and other objects to the netfs. The simplest cookie is just a NULL pointer - indicating nothing cached there. (9) The netfs is allowed to propose - dynamically - any index hierarchy it desires, though it must be aware that the index search function is recursive, stack space is limited, and indices can only be children of indices. (10) Indices can be used to group files together to reduce key size and to make group invalidation easier. The use of indices may make lookup quicker, but that's cache dependent. (11) Data I/O is effectively done directly to and from the netfs's pages. The netfs indicates that page A is at index B of the data-file represented by cookie C, and that it should be read or written. The cache backend may or may not start I/O on that page, but if it does, a netfs callback will be invoked to indicate completion. The I/O may be either synchronous or asynchronous. (12) Cookies can be "retired" upon release. At this point FS-Cache will mark them as obsolete and the index hierarchy rooted at that point will get recycled. (13) The netfs provides a "match" function for index searches. In addition to saying whether a match was made or not, this can also specify that an entry should be updated or deleted. FS-Cache maintains a virtual index tree in which all indices, files, objects and pages are kept. Bits of this tree may actually reside in one or more caches. FSDEF | +------------------------------------+ | | NFS AFS | | +--------------------------+ +-----------+ | | | | homedir mirror afs.org redhat.com | | | +------------+ +---------------+ +----------+ | | | | | | 00001 00002 00007 00125 vol00001 vol00002 | | | | | +---+---+ +-----+ +---+ +------+------+ +-----+----+ | | | | | | | | | | | | | PG0 PG1 PG2 PG0 XATTR PG0 PG1 DIRENT DIRENT DIRENT R/W R/O Bak | | PG0 +-------+ | | 00001 00003 | +---+---+ | | | PG0 PG1 PG2 In the example above, two netfs's can be seen to be backed: NFS and AFS. These have different index hierarchies: (*) The NFS primary index will probably contain per-server indices. Each server index is indexed by NFS file handles to get data file objects. Each data file objects can have an array of pages, but may also have further child objects, such as extended attributes and directory entries. Extended attribute objects themselves have page-array contents. (*) The AFS primary index contains per-cell indices. Each cell index contains per-logical-volume indices. Each of volume index contains up to three indices for the read-write, read-only and backup mirrors of those volumes. Each of these contains vnode data file objects, each of which contains an array of pages. The very top index is the FS-Cache master index in which individual netfs's have entries. Any index object may reside in more than one cache, provided it only has index children. Any index with non-index object children will be assumed to only reside in one cache. The FS-Cache overview can be found in: Documentation/filesystems/caching/fscache.txt The netfs API to FS-Cache can be found in: Documentation/filesystems/caching/netfs-api.txt Signed-off-by: David Howells Acked-by: Steve Dickson Acked-by: Trond Myklebust Acked-by: Al Viro Tested-by: Daire Byrne --- Documentation/filesystems/caching/fscache.txt | 330 ++++++++++ Documentation/filesystems/caching/netfs-api.txt | 778 ++++++++++++++++++++++++ 2 files changed, 1108 insertions(+) create mode 100644 Documentation/filesystems/caching/fscache.txt create mode 100644 Documentation/filesystems/caching/netfs-api.txt (limited to 'Documentation') diff --git a/Documentation/filesystems/caching/fscache.txt b/Documentation/filesystems/caching/fscache.txt new file mode 100644 index 00000000000..a759d916273 --- /dev/null +++ b/Documentation/filesystems/caching/fscache.txt @@ -0,0 +1,330 @@ + ========================== + General Filesystem Caching + ========================== + +======== +OVERVIEW +======== + +This facility is a general purpose cache for network filesystems, though it +could be used for caching other things such as ISO9660 filesystems too. + +FS-Cache mediates between cache backends (such as CacheFS) and network +filesystems: + + +---------+ + | | +--------------+ + | NFS |--+ | | + | | | +-->| CacheFS | + +---------+ | +----------+ | | /dev/hda5 | + | | | | +--------------+ + +---------+ +-->| | | + | | | |--+ + | AFS |----->| FS-Cache | + | | | |--+ + +---------+ +-->| | | + | | | | +--------------+ + +---------+ | +----------+ | | | + | | | +-->| CacheFiles | + | ISOFS |--+ | /var/cache | + | | +--------------+ + +---------+ + +Or to look at it another way, FS-Cache is a module that provides a caching +facility to a network filesystem such that the cache is transparent to the +user: + + +---------+ + | | + | Server | + | | + +---------+ + | NETWORK + ~~~~~|~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + | + | +----------+ + V | | + +---------+ | | + | | | | + | NFS |----->| FS-Cache | + | | | |--+ + +---------+ | | | +--------------+ +--------------+ + | | | | | | | | + V +----------+ +-->| CacheFiles |-->| Ext3 | + +---------+ | /var/cache | | /dev/sda6 | + | | +--------------+ +--------------+ + | VFS | ^ ^ + | | | | + +---------+ +--------------+ | + | KERNEL SPACE | | + ~~~~~|~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~|~~~~~~|~~~~ + | USER SPACE | | + V | | + +---------+ +--------------+ + | | | | + | Process | | cachefilesd | + | | | | + +---------+ +--------------+ + + +FS-Cache does not follow the idea of completely loading every netfs file +opened in its entirety into a cache before permitting it to be accessed and +then serving the pages out of that cache rather than the netfs inode because: + + (1) It must be practical to operate without a cache. + + (2) The size of any accessible file must not be limited to the size of the + cache. + + (3) The combined size of all opened files (this includes mapped libraries) + must not be limited to the size of the cache. + + (4) The user should not be forced to download an entire file just to do a + one-off access of a small portion of it (such as might be done with the + "file" program). + +It instead serves the cache out in PAGE_SIZE chunks as and when requested by +the netfs('s) using it. + + +FS-Cache provides the following facilities: + + (1) More than one cache can be used at once. Caches can be selected + explicitly by use of tags. + + (2) Caches can be added / removed at any time. + + (3) The netfs is provided with an interface that allows either party to + withdraw caching facilities from a file (required for (2)). + + (4) The interface to the netfs returns as few errors as possible, preferring + rather to let the netfs remain oblivious. + + (5) Cookies are used to represent indices, files and other objects to the + netfs. The simplest cookie is just a NULL pointer - indicating nothing + cached there. + + (6) The netfs is allowed to propose - dynamically - any index hierarchy it + desires, though it must be aware that the index search function is + recursive, stack space is limited, and indices can only be children of + indices. + + (7) Data I/O is done direct to and from the netfs's pages. The netfs + indicates that page A is at index B of the data-file represented by cookie + C, and that it should be read or written. The cache backend may or may + not start I/O on that page, but if it does, a netfs callback will be + invoked to indicate completion. The I/O may be either synchronous or + asynchronous. + + (8) Cookies can be "retired" upon release. At this point FS-Cache will mark + them as obsolete and the index hierarchy rooted at that point will get + recycled. + + (9) The netfs provides a "match" function for index searches. In addition to + saying whether a match was made or not, this can also specify that an + entry should be updated or deleted. + +(10) As much as possible is done asynchronously. + + +FS-Cache maintains a virtual indexing tree in which all indices, files, objects +and pages are kept. Bits of this tree may actually reside in one or more +caches. + + FSDEF + | + +------------------------------------+ + | | + NFS AFS + | | + +--------------------------+ +-----------+ + | | | | + homedir mirror afs.org redhat.com + | | | + +------------+ +---------------+ +----------+ + | | | | | | + 00001 00002 00007 00125 vol00001 vol00002 + | | | | | + +---+---+ +-----+ +---+ +------+------+ +-----+----+ + | | | | | | | | | | | | | +PG0 PG1 PG2 PG0 XATTR PG0 PG1 DIRENT DIRENT DIRENT R/W R/O Bak + | | + PG0 +-------+ + | | + 00001 00003 + | + +---+---+ + | | | + PG0 PG1 PG2 + +In the example above, you can see two netfs's being backed: NFS and AFS. These +have different index hierarchies: + + (*) The NFS primary index contains per-server indices. Each server index is + indexed by NFS file handles to get data file objects. Each data file + objects can have an array of pages, but may also have further child + objects, such as extended attributes and directory entries. Extended + attribute objects themselves have page-array contents. + + (*) The AFS primary index contains per-cell indices. Each cell index contains + per-logical-volume indices. Each of volume index contains up to three + indices for the read-write, read-only and backup mirrors of those volumes. + Each of these contains vnode data file objects, each of which contains an + array of pages. + +The very top index is the FS-Cache master index in which individual netfs's +have entries. + +Any index object may reside in more than one cache, provided it only has index +children. Any index with non-index object children will be assumed to only +reside in one cache. + + +The netfs API to FS-Cache can be found in: + + Documentation/filesystems/caching/netfs-api.txt + +The cache backend API to FS-Cache can be found in: + + Documentation/filesystems/caching/backend-api.txt + + +======================= +STATISTICAL INFORMATION +======================= + +If FS-Cache is compiled with the following options enabled: + + CONFIG_FSCACHE_PROC=y (implied by the following two) + CONFIG_FSCACHE_STATS=y + CONFIG_FSCACHE_HISTOGRAM=y + +then it will gather certain statistics and display them through a number of +proc files. + + (*) /proc/fs/fscache/stats + + This shows counts of a number of events that can happen in FS-Cache: + + CLASS EVENT MEANING + ======= ======= ======================================================= + Cookies idx=N Number of index cookies allocated + dat=N Number of data storage cookies allocated + spc=N Number of special cookies allocated + Objects alc=N Number of objects allocated + nal=N Number of object allocation failures + avl=N Number of objects that reached the available state + ded=N Number of objects that reached the dead state + ChkAux non=N Number of objects that didn't have a coherency check + ok=N Number of objects that passed a coherency check + upd=N Number of objects that needed a coherency data update + obs=N Number of objects that were declared obsolete + Pages mrk=N Number of pages marked as being cached + unc=N Number of uncache page requests seen + Acquire n=N Number of acquire cookie requests seen + nul=N Number of acq reqs given a NULL parent + noc=N Number of acq reqs rejected due to no cache available + ok=N Number of acq reqs succeeded + nbf=N Number of acq reqs rejected due to error + oom=N Number of acq reqs failed on ENOMEM + Lookups n=N Number of lookup calls made on cache backends + neg=N Number of negative lookups made + pos=N Number of positive lookups made + crt=N Number of objects created by lookup + Updates n=N Number of update cookie requests seen + nul=N Number of upd reqs given a NULL parent + run=N Number of upd reqs granted CPU time + Relinqs n=N Number of relinquish cookie requests seen + nul=N Number of rlq reqs given a NULL parent + wcr=N Number of rlq reqs waited on completion of creation + AttrChg n=N Number of attribute changed requests seen + ok=N Number of attr changed requests queued + nbf=N Number of attr changed rejected -ENOBUFS + oom=N Number of attr changed failed -ENOMEM + run=N Number of attr changed ops given CPU time + Allocs n=N Number of allocation requests seen + ok=N Number of successful alloc reqs + wt=N Number of alloc reqs that waited on lookup completion + nbf=N Number of alloc reqs rejected -ENOBUFS + ops=N Number of alloc reqs submitted + owt=N Number of alloc reqs waited for CPU time + Retrvls n=N Number of retrieval (read) requests seen + ok=N Number of successful retr reqs + wt=N Number of retr reqs that waited on lookup completion + nod=N Number of retr reqs returned -ENODATA + nbf=N Number of retr reqs rejected -ENOBUFS + int=N Number of retr reqs aborted -ERESTARTSYS + oom=N Number of retr reqs failed -ENOMEM + ops=N Number of retr reqs submitted + owt=N Number of retr reqs waited for CPU time + Stores n=N Number of storage (write) requests seen + ok=N Number of successful store reqs + agn=N Number of store reqs on a page already pending storage + nbf=N Number of store reqs rejected -ENOBUFS + oom=N Number of store reqs failed -ENOMEM + ops=N Number of store reqs submitted + run=N Number of store reqs granted CPU time + Ops pend=N Number of times async ops added to pending queues + run=N Number of times async ops given CPU time + enq=N Number of times async ops queued for processing + dfr=N Number of async ops queued for deferred release + rel=N Number of async ops released + gc=N Number of deferred-release async ops garbage collected + + + (*) /proc/fs/fscache/histogram + + cat /proc/fs/fscache/histogram + +HZ +TIME OBJ INST OP RUNS OBJ RUNS RETRV DLY RETRIEVLS + ===== ===== ========= ========= ========= ========= ========= + + This shows the breakdown of the number of times each amount of time + between 0 jiffies and HZ-1 jiffies a variety of tasks took to run. The + columns are as follows: + + COLUMN TIME MEASUREMENT + ======= ======================================================= + OBJ INST Length of time to instantiate an object + OP RUNS Length of time a call to process an operation took + OBJ RUNS Length of time a call to process an object event took + RETRV DLY Time between an requesting a read and lookup completing + RETRIEVLS Time between beginning and end of a retrieval + + Each row shows the number of events that took a particular range of times. + Each step is 1 jiffy in size. The +HZ column indicates the particular + jiffy range covered, and the +TIME field the equivalent number of seconds. + + +========= +DEBUGGING +========= + +The FS-Cache facility can have runtime debugging enabled by adjusting the value +in: + + /sys/module/fscache/parameters/debug + +This is a bitmask of debugging streams to enable: + + BIT VALUE STREAM POINT + ======= ======= =============================== ======================= + 0 1 Cache management Function entry trace + 1 2 Function exit trace + 2 4 General + 3 8 Cookie management Function entry trace + 4 16 Function exit trace + 5 32 General + 6 64 Page handling Function entry trace + 7 128 Function exit trace + 8 256 General + 9 512 Operation management Function entry trace + 10 1024 Function exit trace + 11 2048 General + +The appropriate set of values should be OR'd together and the result written to +the control file. For example: + + echo $((1|8|64)) >/sys/module/fscache/parameters/debug + +will turn on all function entry debugging. + diff --git a/Documentation/filesystems/caching/netfs-api.txt b/Documentation/filesystems/caching/netfs-api.txt new file mode 100644 index 00000000000..4db125b3a5c --- /dev/null +++ b/Documentation/filesystems/caching/netfs-api.txt @@ -0,0 +1,778 @@ + =============================== + FS-CACHE NETWORK FILESYSTEM API + =============================== + +There's an API by which a network filesystem can make use of the FS-Cache +facilities. This is based around a number of principles: + + (1) Caches can store a number of different object types. There are two main + object types: indices and files. The first is a special type used by + FS-Cache to make finding objects faster and to make retiring of groups of + objects easier. + + (2) Every index, file or other object is represented by a cookie. This cookie + may or may not have anything associated with it, but the netfs doesn't + need to care. + + (3) Barring the top-level index (one entry per cached netfs), the index + hierarchy for each netfs is structured according the whim of the netfs. + +This API is declared in . + +This document contains the following sections: + + (1) Network filesystem definition + (2) Index definition + (3) Object definition + (4) Network filesystem (un)registration + (5) Cache tag lookup + (6) Index registration + (7) Data file registration + (8) Miscellaneous object registration + (9) Setting the data file size + (10) Page alloc/read/write + (11) Page uncaching + (12) Index and data file update + (13) Miscellaneous cookie operations + (14) Cookie unregistration + (15) Index and data file invalidation + (16) FS-Cache specific page flags. + + +============================= +NETWORK FILESYSTEM DEFINITION +============================= + +FS-Cache needs a description of the network filesystem. This is specified +using a record of the following structure: + + struct fscache_netfs { + uint32_t version; + const char *name; + struct fscache_cookie *primary_index; + ... + }; + +This first two fields should be filled in before registration, and the third +will be filled in by the registration function; any other fields should just be +ignored and are for internal use only. + +The fields are: + + (1) The name of the netfs (used as the key in the toplevel index). + + (2) The version of the netfs (if the name matches but the version doesn't, the + entire in-cache hierarchy for this netfs will be scrapped and begun + afresh). + + (3) The cookie representing the primary index will be allocated according to + another parameter passed into the registration function. + +For example, kAFS (linux/fs/afs/) uses the following definitions to describe +itself: + + struct fscache_netfs afs_cache_netfs = { + .version = 0, + .name = "afs", + }; + + +================ +INDEX DEFINITION +================ + +Indices are used for two purposes: + + (1) To aid the finding of a file based on a series of keys (such as AFS's + "cell", "volume ID", "vnode ID"). + + (2) To make it easier to discard a subset of all the files cached based around + a particular key - for instance to mirror the removal of an AFS volume. + +However, since it's unlikely that any two netfs's are going to want to define +their index hierarchies in quite the same way, FS-Cache tries to impose as few +restraints as possible on how an index is structured and where it is placed in +the tree. The netfs can even mix indices and data files at the same level, but +it's not recommended. + +Each index entry consists of a key of indeterminate length plus some auxilliary +data, also of indeterminate length. + +There are some limits on indices: + + (1) Any index containing non-index objects should be restricted to a single + cache. Any such objects created within an index will be created in the + first cache only. The cache in which an index is created can be + controlled by cache tags (see below). + + (2) The entry data must be atomically journallable, so it is limited to about + 400 bytes at present. At least 400 bytes will be available. + + (3) The depth of the index tree should be judged with care as the search + function is recursive. Too many layers will run the kernel out of stack. + + +================= +OBJECT DEFINITION +================= + +To define an object, a structure of the following type should be filled out: + + struct fscache_cookie_def + { + uint8_t name[16]; + uint8_t type; + + struct fscache_cache_tag *(*select_cache)( + const void *parent_netfs_data, + const void *cookie_netfs_data); + + uint16_t (*get_key)(const void *cookie_netfs_data, + void *buffer, + uint16_t bufmax); + + void (*get_attr)(const void *cookie_netfs_data, + uint64_t *size); + + uint16_t (*get_aux)(const void *cookie_netfs_data, + void *buffer, + uint16_t bufmax); + + enum fscache_checkaux (*check_aux)(void *cookie_netfs_data, + const void *data, + uint16_t datalen); + + void (*get_context)(void *cookie_netfs_data, void *context); + + void (*put_context)(void *cookie_netfs_data, void *context); + + void (*mark_pages_cached)(void *cookie_netfs_data, + struct address_space *mapping, + struct pagevec *cached_pvec); + + void (*now_uncached)(void *cookie_netfs_data); + }; + +This has the following fields: + + (1) The type of the object [mandatory]. + + This is one of the following values: + + (*) FSCACHE_COOKIE_TYPE_INDEX + + This defines an index, which is a special FS-Cache type. + + (*) FSCACHE_COOKIE_TYPE_DATAFILE + + This defines an ordinary data file. + + (*) Any other value between 2 and 255 + + This defines an extraordinary object such as an XATTR. + + (2) The name of the object type (NUL terminated unless all 16 chars are used) + [optional]. + + (3) A function to select the cache in which to store an index [optional]. + + This function is invoked when an index needs to be instantiated in a cache + during the instantiation of a non-index object. Only the immediate index + parent for the non-index object will be queried. Any indices above that + in the hierarchy may be stored in multiple caches. This function does not + need to be supplied for any non-index object or any index that will only + have index children. + + If this function is not supplied or if it returns NULL then the first + cache in the parent's list will be chosed, or failing that, the first + cache in the master list. + + (4) A function to retrieve an object's key from the netfs [mandatory]. + + This function will be called with the netfs data that was passed to the + cookie acquisition function and the maximum length of key data that it may + provide. It should write the required key data into the given buffer and + return the quantity it wrote. + + (5) A function to retrieve attribute data from the netfs [optional]. + + This function will be called with the netfs data that was passed to the + cookie acquisition function. It should return the size of the file if + this is a data file. The size may be used to govern how much cache must + be reserved for this file in the cache. + + If the function is absent, a file size of 0 is assumed. + + (6) A function to retrieve auxilliary data from the netfs [optional]. + + This function will be called with the netfs data that was passed to the + cookie acquisition function and the maximum length of auxilliary data that + it may provide. It should write the auxilliary data into the given buffer + and return the quantity it wrote. + + If this function is absent, the auxilliary data length will be set to 0. + + The length of the auxilliary data buffer may be dependent on the key + length. A netfs mustn't rely on being able to provide more than 400 bytes + for both. + + (7) A function to check the auxilliary data [optional]. + + This function will be called to check that a match found in the cache for + this object is valid. For instance with AFS it could check the auxilliary + data against the data version number returned by the server to determine + whether the index entry in a cache is still valid. + + If this function is absent, it will be assumed that matching objects in a + cache are always valid. + + If present, the function should return one of the following values: + + (*) FSCACHE_CHECKAUX_OKAY - the entry is okay as is + (*) FSCACHE_CHECKAUX_NEEDS_UPDATE - the entry requires update + (*) FSCACHE_CHECKAUX_OBSOLETE - the entry should be deleted + + This function can also be used to extract data from the auxilliary data in + the cache and copy it into the netfs's structures. + + (8) A pair of functions to manage contexts for the completion callback + [optional]. + + The cache read/write functions are passed a context which is then passed + to the I/O completion callback function. To ensure this context remains + valid until after the I/O completion is called, two functions may be + provided: one to get an extra reference on the context, and one to drop a + reference to it. + + If the context is not used or is a type of object that won't go out of + scope, then these functions are not required. These functions are not + required for indices as indices may not contain data. These functions may + be called in interrupt context and so may not sleep. + + (9) A function to mark a page as retaining cache metadata [optional]. + + This is called by the cache to indicate that it is retaining in-memory + information for this page and that the netfs should uncache the page when + it has finished. This does not indicate whether there's data on the disk + or not. Note that several pages at once may be presented for marking. + + The PG_fscache bit is set on the pages before this function would be + called, so the function need not be provided if this is sufficient. + + This function is not required for indices as they're not permitted data. + +(10) A function to unmark all the pages retaining cache metadata [mandatory]. + + This is called by FS-Cache to indicate that a backing store is being + unbound from a cookie and that all the marks on the pages should be + cleared to prevent confusion. Note that the cache will have torn down all + its tracking information so that the pages don't need to be explicitly + uncached. + + This function is not required for indices as they're not permitted data. + + +=================================== +NETWORK FILESYSTEM (UN)REGISTRATION +=================================== + +The first step is to declare the network filesystem to the cache. This also +involves specifying the layout of the primary index (for AFS, this would be the +"cell" level). + +The registration function is: + + int fscache_register_netfs(struct fscache_netfs *netfs); + +It just takes a pointer to the netfs definition. It returns 0 or an error as +appropriate. + +For kAFS, registration is done as follows: + + ret = fscache_register_netfs(&afs_cache_netfs); + +The last step is, of course, unregistration: + + void fscache_unregister_netfs(struct fscache_netfs *netfs); + + +================ +CACHE TAG LOOKUP +================ + +FS-Cache permits the use of more than one cache. To permit particular index +subtrees to be bound to particular caches, the second step is to look up cache +representation tags. This step is optional; it can be left entirely up to +FS-Cache as to which cache should be used. The problem with doing that is that +FS-Cache will always pick the first cache that was registered. + +To get the representation for a named tag: + + struct fscache_cache_tag *fscache_lookup_cache_tag(const char *name); + +This takes a text string as the name and returns a representation of a tag. It +will never return an error. It may return a dummy tag, however, if it runs out +of memory; this will inhibit caching with this tag. + +Any representation so obtained must be released by passing it to this function: + + void fscache_release_cache_tag(struct fscache_cache_tag *tag); + +The tag will be retrieved by FS-Cache when it calls the object definition +operation select_cache(). + + +================== +INDEX REGISTRATION +================== + +The third step is to inform FS-Cache about part of an index hierarchy that can +be used to locate files. This is done by requesting a cookie for each index in +the path to the file: + + struct fscache_cookie * + fscache_acquire_cookie(struct fscache_cookie *parent, + const struct fscache_object_def *def, + void *netfs_data); + +This function creates an index entry in the index represented by parent, +filling in the index entry by calling the operations pointed to by def. + +Note that this function never returns an error - all errors are handled +internally. It may, however, return NULL to indicate no cookie. It is quite +acceptable to pass this token back to this function as the parent to another +acquisition (or even to the relinquish cookie, read page and write page +functions - see below). + +Note also that no indices are actually created in a cache until a non-index +object needs to be created somewhere down the hierarchy. Furthermore, an index +may be created in several different caches independently at different times. +This is all handled transparently, and the netfs doesn't see any of it. + +For example, with AFS, a cell would be added to the primary index. This index +entry would have a dependent inode containing a volume location index for the +volume mappings within this cell: + + cell->cache = + fscache_acquire_cookie(afs_cache_netfs.primary_index, + &afs_cell_cache_index_def, + cell); + +Then when a volume location was accessed, it would be entered into the cell's +index and an inode would be allocated that acts as a volume type and hash chain +combination: + + vlocation->cache = + fscache_acquire_cookie(cell->cache, + &afs_vlocation_cache_index_def, + vlocation); + +And then a particular flavour of volume (R/O for example) could be added to +that index, creating another index for vnodes (AFS inode equivalents): + + volume->cache = + fscache_acquire_cookie(vlocation->cache, + &afs_volume_cache_index_def, + volume); + + +====================== +DATA FILE REGISTRATION +====================== + +The fourth step is to request a data file be created in the cache. This is +identical to index cookie acquisition. The only difference is that the type in +the object definition should be something other than index type. + + vnode->cache = + fscache_acquire_cookie(volume->cache, + &afs_vnode_cache_object_def, + vnode); + + +================================= +MISCELLANEOUS OBJECT REGISTRATION +================================= + +An optional step is to request an object of miscellaneous type be created in +the cache. This is almost identical to index cookie acquisition. The only +difference is that the type in the object definition should be something other +than index type. Whilst the parent object could be an index, it's more likely +it would be some other type of object such as a data file. + + xattr->cache = + fscache_acquire_cookie(vnode->cache, + &afs_xattr_cache_object_def, + xattr); + +Miscellaneous objects might be used to store extended attributes or directory +entries for example. + + +========================== +SETTING THE DATA FILE SIZE +========================== + +The fifth step is to set the physical attributes of the file, such as its size. +This doesn't automatically reserve any space in the cache, but permits the +cache to adjust its metadata for data tracking appropriately: + + int fscache_attr_changed(struct fscache_cookie *cookie); + +The cache will return -ENOBUFS if there is no backing cache or if there is no +space to allocate any extra metadata required in the cache. The attributes +will be accessed with the get_attr() cookie definition operation. + +Note that attempts to read or write data pages in the cache over this size may +be rebuffed with -ENOBUFS. + +This operation schedules an attribute adjustment to happen asynchronously at +some point in the future, and as such, it may happen after the function returns +to the caller. The attribute adjustment excludes read and write operations. + + +===================== +PAGE READ/ALLOC/WRITE +===================== + +And the sixth step is to store and retrieve pages in the cache. There are +three functions that are used to do this. + +Note: + + (1) A page should not be re-read or re-allocated without uncaching it first. + + (2) A read or allocated page must be uncached when the netfs page is released + from the pagecache. + + (3) A page should only be written to the cache if previous read or allocated. + +This permits the cache to maintain its page tracking in proper order. + + +PAGE READ +--------- + +Firstly, the netfs should ask FS-Cache to examine the caches and read the +contents cached for a particular page of a particular file if present, or else +allocate space to store the contents if not: + + typedef + void (*fscache_rw_complete_t)(struct page *page, + void *context, + int error); + + int fscache_read_or_alloc_page(struct fscache_cookie *cookie, + struct page *page, + fscache_rw_complete_t end_io_func, + void *context, + gfp_t gfp); + +The cookie argument must specify a cookie for an object that isn't an index, +the page specified will have the data loaded into it (and is also used to +specify the page number), and the gfp argument is used to control how any +memory allocations made are satisfied. + +If the cookie indicates the inode is not cached: + + (1) The function will return -ENOBUFS. + +Else if there's a copy of the page resident in the cache: + + (1) The mark_pages_cached() cookie operation will be called on that page. + + (2) The function will submit a request to read the data from the cache's + backing device directly into the page specified. + + (3) The function will return 0. + + (4) When the read is complete, end_io_func() will be invoked with: + + (*) The netfs data supplied when the cookie was created. + + (*) The page descriptor. + + (*) The context argument passed to the above function. This will be + maintained with the get_context/put_context functions mentioned above. + + (*) An argument that's 0 on success or negative for an error code. + + If an error occurs, it should be assumed that the page contains no usable + data. + + end_io_func() will be called in process context if the read is results in + an error, but it might be called in interrupt context if the read is + successful. + +Otherwise, if there's not a copy available in cache, but the cache may be able +to store the page: + + (1) The mark_pages_cached() cookie operation will be called on that page. + + (2) A block may be reserved in the cache and attached to the object at the + appropriate place. + + (3) The function will return -ENODATA. + +This function may also return -ENOMEM or -EINTR, in which case it won't have +read any data from the cache. + + +PAGE ALLOCATE +------------- + +Alternatively, if there's not expected to be any data in the cache for a page +because the file has been extended, a block can simply be allocated instead: + + int fscache_alloc_page(struct fscache_cookie *cookie, + struct page *page, + gfp_t gfp); + +This is similar to the fscache_read_or_alloc_page() function, except that it +never reads from the cache. It will return 0 if a block has been allocated, +rather than -ENODATA as the other would. One or the other must be performed +before writing to the cache. + +The mark_pages_cached() cookie operation will be called on the page if +successful. + + +PAGE WRITE +---------- + +Secondly, if the netfs changes the contents of the page (either due to an +initial download or if a user performs a write), then the page should be +written back to the cache: + + int fscache_write_page(struct fscache_cookie *cookie, + struct page *page, + gfp_t gfp); + +The cookie argument must specify a data file cookie, the page specified should +contain the data to be written (and is also used to specify the page number), +and the gfp argument is used to control how any memory allocations made are +satisfied. + +The page must have first been read or allocated successfully and must not have +been uncached before writing is performed. + +If the cookie indicates the inode is not cached then: + + (1) The function will return -ENOBUFS. + +Else if space can be allocated in the cache to hold this page: + + (1) PG_fscache_write will be set on the page. + + (2) The function will submit a request to write the data to cache's backing + device directly from the page specified. + + (3) The function will return 0. + + (4) When the write is complete PG_fscache_write is cleared on the page and + anyone waiting for that bit will be woken up. + +Else if there's no space available in the cache, -ENOBUFS will be returned. It +is also possible for the PG_fscache_write bit to be cleared when no write took +place if unforeseen circumstances arose (such as a disk error). + +Writing takes place asynchronously. + + +MULTIPLE PAGE READ +------------------ + +A facility is provided to read several pages at once, as requested by the +readpages() address space operation: + + int fscache_read_or_alloc_pages(struct fscache_cookie *cookie, + struct address_space *mapping, + struct list_head *pages, + int *nr_pages, + fscache_rw_complete_t end_io_func, + void *context, + gfp_t gfp); + +This works in a similar way to fscache_read_or_alloc_page(), except: + + (1) Any page it can retrieve data for is removed from pages and nr_pages and + dispatched for reading to the disk. Reads of adjacent pages on disk may + be merged for greater efficiency. + + (2) The mark_pages_cached() cookie operation will be called on several pages + at once if they're being read or allocated. + + (3) If there was an general error, then that error will be returned. + + Else if some pages couldn't be allocated or read, then -ENOBUFS will be + returned. + + Else if some pages couldn't be read but were allocated, then -ENODATA will + be returned. + + Otherwise, if all pages had reads dispatched, then 0 will be returned, the + list will be empty and *nr_pages will be 0. + + (4) end_io_func will be called once for each page being read as the reads + complete. It will be called in process context if error != 0, but it may + be called in interrupt context if there is no error. + +Note that a return of -ENODATA, -ENOBUFS or any other error does not preclude +some of the pages being read and some being allocated. Those pages will have +been marked appropriately and will need uncaching. + + +============== +PAGE UNCACHING +============== + +To uncache a page, this function should be called: + + void fscache_uncache_page(struct fscache_cookie *cookie, + struct page *page); + +This function permits the cache to release any in-memory representation it +might be holding for this netfs page. This function must be called once for +each page on which the read or write page functions above have been called to +make sure the cache's in-memory tracking information gets torn down. + +Note that pages can't be explicitly deleted from the a data file. The whole +data file must be retired (see the relinquish cookie function below). + +Furthermore, note that this does not cancel the asynchronous read or write +operation started by the read/alloc and write functions, so the page +invalidation and release functions must use: + + bool fscache_check_page_write(struct fscache_cookie *cookie, + struct page *page); + +to see if a page is being written to the cache, and: + + void fscache_wait_on_page_write(struct fscache_cookie *cookie, + struct page *page); + +to wait for it to finish if it is. + + +========================== +INDEX AND DATA FILE UPDATE +========================== + +To request an update of the index data for an index or other object, the +following function should be called: + + void fscache_update_cookie(struct fscache_cookie *cookie); + +This function will refer back to the netfs_data pointer stored in the cookie by +the acquisition function to obtain the data to write into each revised index +entry. The update method in the parent index definition will be called to +transfer the data. + +Note that partial updates may happen automatically at other times, such as when +data blocks are added to a data file object. + + +=============================== +MISCELLANEOUS COOKIE OPERATIONS +=============================== + +There are a number of operations that can be used to control cookies: + + (*) Cookie pinning: + + int fscache_pin_cookie(struct fscache_cookie *cookie); + void fscache_unpin_cookie(struct fscache_cookie *cookie); + + These operations permit data cookies to be pinned into the cache and to + have the pinning removed. They are not permitted on index cookies. + + The pinning function will return 0 if successful, -ENOBUFS in the cookie + isn't backed by a cache, -EOPNOTSUPP if the cache doesn't support pinning, + -ENOSPC if there isn't enough space to honour the operation, -ENOMEM or + -EIO if there's any other problem. + + (*) Data space reservation: + + int fscache_reserve_space(struct fscache_cookie *cookie, loff_t size); + + This permits a netfs to request cache space be reserved to store up to the + given amount of a file. It is permitted to ask for more than the current + size of the file to allow for future file expansion. + + If size is given as zero then the reservation will be cancelled. + + The function will return 0 if successful, -ENOBUFS in the cookie isn't + backed by a cache, -EOPNOTSUPP if the cache doesn't support reservations, + -ENOSPC if there isn't enough space to honour the operation, -ENOMEM or + -EIO if there's any other problem. + + Note that this doesn't pin an object in a cache; it can still be culled to + make space if it's not in use. + + +===================== +COOKIE UNREGISTRATION +===================== + +To get rid of a cookie, this function should be called. + + void fscache_relinquish_cookie(struct fscache_cookie *cookie, + int retire); + +If retire is non-zero, then the object will be marked for recycling, and all +copies of it will be removed from all active caches in which it is present. +Not only that but all child objects will also be retired. + +If retire is zero, then the object may be available again when next the +acquisition function is called. Retirement here will overrule the pinning on a +cookie. + +One very important note - relinquish must NOT be called for a cookie unless all +the cookies for "child" indices, objects and pages have been relinquished +first. + + +================================ +INDEX AND DATA FILE INVALIDATION +================================ + +There is no direct way to invalidate an index subtree or a data file. To do +this, the caller should relinquish and retire the cookie they have, and then +acquire a new one. + + +=========================== +FS-CACHE SPECIFIC PAGE FLAG +=========================== + +FS-Cache makes use of a page flag, PG_private_2, for its own purpose. This is +given the alternative name PG_fscache. + +PG_fscache is used to indicate that the page is known by the cache, and that +the cache must be informed if the page is going to go away. It's an indication +to the netfs that the cache has an interest in this page, where an interest may +be a pointer to it, resources allocated or reserved for it, or I/O in progress +upon it. + +The netfs can use this information in methods such as releasepage() to +determine whether it needs to uncache a page or update it. + +Furthermore, if this bit is set, releasepage() and invalidatepage() operations +will be called on a page to get rid of it, even if PG_private is not set. This +allows caching to attempted on a page before read_cache_pages() to be called +after fscache_read_or_alloc_pages() as the former will try and release pages it +was given under certain circumstances. + +This bit does not overlap with such as PG_private. This means that FS-Cache +can be used with a filesystem that uses the block buffering code. + +There are a number of operations defined on this flag: + + int PageFsCache(struct page *page); + void SetPageFsCache(struct page *page) + void ClearPageFsCache(struct page *page) + int TestSetPageFsCache(struct page *page) + int TestClearPageFsCache(struct page *page) + +These functions are bit test, bit set, bit clear, bit test and set and bit +test and clear operations on PG_fscache. -- cgit v1.2.3 From 0dfc41d1efcc4180abfd32f68f0ade540e636ff6 Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 3 Apr 2009 16:42:36 +0100 Subject: FS-Cache: Add the FS-Cache cache backend API and documentation Add the API for a generic facility (FS-Cache) by which caches may declare them selves open for business, and may obtain work to be done from network filesystems. The header file is included by: #include Documentation for the API is also added to: Documentation/filesystems/caching/backend-api.txt This API is not usable without the implementation of the utility functions which will be added in further patches. Signed-off-by: David Howells Acked-by: Steve Dickson Acked-by: Trond Myklebust Acked-by: Al Viro Tested-by: Daire Byrne --- Documentation/filesystems/caching/backend-api.txt | 664 ++++++++++++++++++++++ 1 file changed, 664 insertions(+) create mode 100644 Documentation/filesystems/caching/backend-api.txt (limited to 'Documentation') diff --git a/Documentation/filesystems/caching/backend-api.txt b/Documentation/filesystems/caching/backend-api.txt new file mode 100644 index 00000000000..17723053aa9 --- /dev/null +++ b/Documentation/filesystems/caching/backend-api.txt @@ -0,0 +1,664 @@ + ========================== + FS-CACHE CACHE BACKEND API + ========================== + +The FS-Cache system provides an API by which actual caches can be supplied to +FS-Cache for it to then serve out to network filesystems and other interested +parties. + +This API is declared in . + + +==================================== +INITIALISING AND REGISTERING A CACHE +==================================== + +To start off, a cache definition must be initialised and registered for each +cache the backend wants to make available. For instance, CacheFS does this in +the fill_super() operation on mounting. + +The cache definition (struct fscache_cache) should be initialised by calling: + + void fscache_init_cache(struct fscache_cache *cache, + struct fscache_cache_ops *ops, + const char *idfmt, + ...); + +Where: + + (*) "cache" is a pointer to the cache definition; + + (*) "ops" is a pointer to the table of operations that the backend supports on + this cache; and + + (*) "idfmt" is a format and printf-style arguments for constructing a label + for the cache. + + +The cache should then be registered with FS-Cache by passing a pointer to the +previously initialised cache definition to: + + int fscache_add_cache(struct fscache_cache *cache, + struct fscache_object *fsdef, + const char *tagname); + +Two extra arguments should also be supplied: + + (*) "fsdef" which should point to the object representation for the FS-Cache + master index in this cache. Netfs primary index entries will be created + here. FS-Cache keeps the caller's reference to the index object if + successful and will release it upon withdrawal of the cache. + + (*) "tagname" which, if given, should be a text string naming this cache. If + this is NULL, the identifier will be used instead. For CacheFS, the + identifier is set to name the underlying block device and the tag can be + supplied by mount. + +This function may return -ENOMEM if it ran out of memory or -EEXIST if the tag +is already in use. 0 will be returned on success. + + +===================== +UNREGISTERING A CACHE +===================== + +A cache can be withdrawn from the system by calling this function with a +pointer to the cache definition: + + void fscache_withdraw_cache(struct fscache_cache *cache); + +In CacheFS's case, this is called by put_super(). + + +======== +SECURITY +======== + +The cache methods are executed one of two contexts: + + (1) that of the userspace process that issued the netfs operation that caused + the cache method to be invoked, or + + (2) that of one of the processes in the FS-Cache thread pool. + +In either case, this may not be an appropriate context in which to access the +cache. + +The calling process's fsuid, fsgid and SELinux security identities may need to +be masqueraded for the duration of the cache driver's access to the cache. +This is left to the cache to handle; FS-Cache makes no effort in this regard. + + +=================================== +CONTROL AND STATISTICS PRESENTATION +=================================== + +The cache may present data to the outside world through FS-Cache's interfaces +in sysfs and procfs - the former for control and the latter for statistics. + +A sysfs directory called /sys/fs/fscache// is created if CONFIG_SYSFS +is enabled. This is accessible through the kobject struct fscache_cache::kobj +and is for use by the cache as it sees fit. + +The cache driver may create itself a directory named for the cache type in the +/proc/fs/fscache/ directory. This is available if CONFIG_FSCACHE_PROC is +enabled and is accessible through: + + struct proc_dir_entry *proc_fscache; + + +======================== +RELEVANT DATA STRUCTURES +======================== + + (*) Index/Data file FS-Cache representation cookie: + + struct fscache_cookie { + struct fscache_object_def *def; + struct fscache_netfs *netfs; + void *netfs_data; + ... + }; + + The fields that might be of use to the backend describe the object + definition, the netfs definition and the netfs's data for this cookie. + The object definition contain functions supplied by the netfs for loading + and matching index entries; these are required to provide some of the + cache operations. + + + (*) In-cache object representation: + + struct fscache_object { + int debug_id; + enum { + FSCACHE_OBJECT_RECYCLING, + ... + } state; + spinlock_t lock + struct fscache_cache *cache; + struct fscache_cookie *cookie; + ... + }; + + Structures of this type should be allocated by the cache backend and + passed to FS-Cache when requested by the appropriate cache operation. In + the case of CacheFS, they're embedded in CacheFS's internal object + structures. + + The debug_id is a simple integer that can be used in debugging messages + that refer to a particular object. In such a case it should be printed + using "OBJ%x" to be consistent with FS-Cache. + + Each object contains a pointer to the cookie that represents the object it + is backing. An object should retired when put_object() is called if it is + in state FSCACHE_OBJECT_RECYCLING. The fscache_object struct should be + initialised by calling fscache_object_init(object). + + + (*) FS-Cache operation record: + + struct fscache_operation { + atomic_t usage; + struct fscache_object *object; + unsigned long flags; + #define FSCACHE_OP_EXCLUSIVE + void (*processor)(struct fscache_operation *op); + void (*release)(struct fscache_operation *op); + ... + }; + + FS-Cache has a pool of threads that it uses to give CPU time to the + various asynchronous operations that need to be done as part of driving + the cache. These are represented by the above structure. The processor + method is called to give the op CPU time, and the release method to get + rid of it when its usage count reaches 0. + + An operation can be made exclusive upon an object by setting the + appropriate flag before enqueuing it with fscache_enqueue_operation(). If + an operation needs more processing time, it should be enqueued again. + + + (*) FS-Cache retrieval operation record: + + struct fscache_retrieval { + struct fscache_operation op; + struct address_space *mapping; + struct list_head *to_do; + ... + }; + + A structure of this type is allocated by FS-Cache to record retrieval and + allocation requests made by the netfs. This struct is then passed to the + backend to do the operation. The backend may get extra refs to it by + calling fscache_get_retrieval() and refs may be discarded by calling + fscache_put_retrieval(). + + A retrieval operation can be used by the backend to do retrieval work. To + do this, the retrieval->op.processor method pointer should be set + appropriately by the backend and fscache_enqueue_retrieval() called to + submit it to the thread pool. CacheFiles, for example, uses this to queue + page examination when it detects PG_lock being cleared. + + The to_do field is an empty list available for the cache backend to use as + it sees fit. + + + (*) FS-Cache storage operation record: + + struct fscache_storage { + struct fscache_operation op; + pgoff_t store_limit; + ... + }; + + A structure of this type is allocated by FS-Cache to record outstanding + writes to be made. FS-Cache itself enqueues this operation and invokes + the write_page() method on the object at appropriate times to effect + storage. + + +================ +CACHE OPERATIONS +================ + +The cache backend provides FS-Cache with a table of operations that can be +performed on the denizens of the cache. These are held in a structure of type: + + struct fscache_cache_ops + + (*) Name of cache provider [mandatory]: + + const char *name + + This isn't strictly an operation, but should be pointed at a string naming + the backend. + + + (*) Allocate a new object [mandatory]: + + struct fscache_object *(*alloc_object)(struct fscache_cache *cache, + struct fscache_cookie *cookie) + + This method is used to allocate a cache object representation to back a + cookie in a particular cache. fscache_object_init() should be called on + the object to initialise it prior to returning. + + This function may also be used to parse the index key to be used for + multiple lookup calls to turn it into a more convenient form. FS-Cache + will call the lookup_complete() method to allow the cache to release the + form once lookup is complete or aborted. + + + (*) Look up and create object [mandatory]: + + void (*lookup_object)(struct fscache_object *object) + + This method is used to look up an object, given that the object is already + allocated and attached to the cookie. This should instantiate that object + in the cache if it can. + + The method should call fscache_object_lookup_negative() as soon as + possible if it determines the object doesn't exist in the cache. If the + object is found to exist and the netfs indicates that it is valid then + fscache_obtained_object() should be called once the object is in a + position to have data stored in it. Similarly, fscache_obtained_object() + should also be called once a non-present object has been created. + + If a lookup error occurs, fscache_object_lookup_error() should be called + to abort the lookup of that object. + + + (*) Release lookup data [mandatory]: + + void (*lookup_complete)(struct fscache_object *object) + + This method is called to ask the cache to release any resources it was + using to perform a lookup. + + + (*) Increment object refcount [mandatory]: + + struct fscache_object *(*grab_object)(struct fscache_object *object) + + This method is called to increment the reference count on an object. It + may fail (for instance if the cache is being withdrawn) by returning NULL. + It should return the object pointer if successful. + + + (*) Lock/Unlock object [mandatory]: + + void (*lock_object)(struct fscache_object *object) + void (*unlock_object)(struct fscache_object *object) + + These methods are used to exclusively lock an object. It must be possible + to schedule with the lock held, so a spinlock isn't sufficient. + + + (*) Pin/Unpin object [optional]: + + int (*pin_object)(struct fscache_object *object) + void (*unpin_object)(struct fscache_object *object) + + These methods are used to pin an object into the cache. Once pinned an + object cannot be reclaimed to make space. Return -ENOSPC if there's not + enough space in the cache to permit this. + + + (*) Update object [mandatory]: + + int (*update_object)(struct fscache_object *object) + + This is called to update the index entry for the specified object. The + new information should be in object->cookie->netfs_data. This can be + obtained by calling object->cookie->def->get_aux()/get_attr(). + + + (*) Discard object [mandatory]: + + void (*drop_object)(struct fscache_object *object) + + This method is called to indicate that an object has been unbound from its + cookie, and that the cache should release the object's resources and + retire it if it's in state FSCACHE_OBJECT_RECYCLING. + + This method should not attempt to release any references held by the + caller. The caller will invoke the put_object() method as appropriate. + + + (*) Release object reference [mandatory]: + + void (*put_object)(struct fscache_object *object) + + This method is used to discard a reference to an object. The object may + be freed when all the references to it are released. + + + (*) Synchronise a cache [mandatory]: + + void (*sync)(struct fscache_cache *cache) + + This is called to ask the backend to synchronise a cache with its backing + device. + + + (*) Dissociate a cache [mandatory]: + + void (*dissociate_pages)(struct fscache_cache *cache) + + This is called to ask a cache to perform any page dissociations as part of + cache withdrawal. + + + (*) Notification that the attributes on a netfs file changed [mandatory]: + + int (*attr_changed)(struct fscache_object *object); + + This is called to indicate to the cache that certain attributes on a netfs + file have changed (for example the maximum size a file may reach). The + cache can read these from the netfs by calling the cookie's get_attr() + method. + + The cache may use the file size information to reserve space on the cache. + It should also call fscache_set_store_limit() to indicate to FS-Cache the + highest byte it's willing to store for an object. + + This method may return -ve if an error occurred or the cache object cannot + be expanded. In such a case, the object will be withdrawn from service. + + This operation is run asynchronously from FS-Cache's thread pool, and + storage and retrieval operations from the netfs are excluded during the + execution of this operation. + + + (*) Reserve cache space for an object's data [optional]: + + int (*reserve_space)(struct fscache_object *object, loff_t size); + + This is called to request that cache space be reserved to hold the data + for an object and the metadata used to track it. Zero size should be + taken as request to cancel a reservation. + + This should return 0 if successful, -ENOSPC if there isn't enough space + available, or -ENOMEM or -EIO on other errors. + + The reservation may exceed the current size of the object, thus permitting + future expansion. If the amount of space consumed by an object would + exceed the reservation, it's permitted to refuse requests to allocate + pages, but not required. An object may be pruned down to its reservation + size if larger than that already. + + + (*) Request page be read from cache [mandatory]: + + int (*read_or_alloc_page)(struct fscache_retrieval *op, + struct page *page, + gfp_t gfp) + + This is called to attempt to read a netfs page from the cache, or to + reserve a backing block if not. FS-Cache will have done as much checking + as it can before calling, but most of the work belongs to the backend. + + If there's no page in the cache, then -ENODATA should be returned if the + backend managed to reserve a backing block; -ENOBUFS or -ENOMEM if it + didn't. + + If there is suitable data in the cache, then a read operation should be + queued and 0 returned. When the read finishes, fscache_end_io() should be + called. + + The fscache_mark_pages_cached() should be called for the page if any cache + metadata is retained. This will indicate to the netfs that the page needs + explicit uncaching. This operation takes a pagevec, thus allowing several + pages to be marked at once. + + The retrieval record pointed to by op should be retained for each page + queued and released when I/O on the page has been formally ended. + fscache_get/put_retrieval() are available for this purpose. + + The retrieval record may be used to get CPU time via the FS-Cache thread + pool. If this is desired, the op->op.processor should be set to point to + the appropriate processing routine, and fscache_enqueue_retrieval() should + be called at an appropriate point to request CPU time. For instance, the + retrieval routine could be enqueued upon the completion of a disk read. + The to_do field in the retrieval record is provided to aid in this. + + If an I/O error occurs, fscache_io_error() should be called and -ENOBUFS + returned if possible or fscache_end_io() called with a suitable error + code.. + + + (*) Request pages be read from cache [mandatory]: + + int (*read_or_alloc_pages)(struct fscache_retrieval *op, + struct list_head *pages, + unsigned *nr_pages, + gfp_t gfp) + + This is like the read_or_alloc_page() method, except it is handed a list + of pages instead of one page. Any pages on which a read operation is + started must be added to the page cache for the specified mapping and also + to the LRU. Such pages must also be removed from the pages list and + *nr_pages decremented per page. + + If there was an error such as -ENOMEM, then that should be returned; else + if one or more pages couldn't be read or allocated, then -ENOBUFS should + be returned; else if one or more pages couldn't be read, then -ENODATA + should be returned. If all the pages are dispatched then 0 should be + returned. + + + (*) Request page be allocated in the cache [mandatory]: + + int (*allocate_page)(struct fscache_retrieval *op, + struct page *page, + gfp_t gfp) + + This is like the read_or_alloc_page() method, except that it shouldn't + read from the cache, even if there's data there that could be retrieved. + It should, however, set up any internal metadata required such that + the write_page() method can write to the cache. + + If there's no backing block available, then -ENOBUFS should be returned + (or -ENOMEM if there were other problems). If a block is successfully + allocated, then the netfs page should be marked and 0 returned. + + + (*) Request pages be allocated in the cache [mandatory]: + + int (*allocate_pages)(struct fscache_retrieval *op, + struct list_head *pages, + unsigned *nr_pages, + gfp_t gfp) + + This is an multiple page version of the allocate_page() method. pages and + nr_pages should be treated as for the read_or_alloc_pages() method. + + + (*) Request page be written to cache [mandatory]: + + int (*write_page)(struct fscache_storage *op, + struct page *page); + + This is called to write from a page on which there was a previously + successful read_or_alloc_page() call or similar. FS-Cache filters out + pages that don't have mappings. + + This method is called asynchronously from the FS-Cache thread pool. It is + not required to actually store anything, provided -ENODATA is then + returned to the next read of this page. + + If an error occurred, then a negative error code should be returned, + otherwise zero should be returned. FS-Cache will take appropriate action + in response to an error, such as withdrawing this object. + + If this method returns success then FS-Cache will inform the netfs + appropriately. + + + (*) Discard retained per-page metadata [mandatory]: + + void (*uncache_page)(struct fscache_object *object, struct page *page) + + This is called when a netfs page is being evicted from the pagecache. The + cache backend should tear down any internal representation or tracking it + maintains for this page. + + +================== +FS-CACHE UTILITIES +================== + +FS-Cache provides some utilities that a cache backend may make use of: + + (*) Note occurrence of an I/O error in a cache: + + void fscache_io_error(struct fscache_cache *cache) + + This tells FS-Cache that an I/O error occurred in the cache. After this + has been called, only resource dissociation operations (object and page + release) will be passed from the netfs to the cache backend for the + specified cache. + + This does not actually withdraw the cache. That must be done separately. + + + (*) Invoke the retrieval I/O completion function: + + void fscache_end_io(struct fscache_retrieval *op, struct page *page, + int error); + + This is called to note the end of an attempt to retrieve a page. The + error value should be 0 if successful and an error otherwise. + + + (*) Set highest store limit: + + void fscache_set_store_limit(struct fscache_object *object, + loff_t i_size); + + This sets the limit FS-Cache imposes on the highest byte it's willing to + try and store for a netfs. Any page over this limit is automatically + rejected by fscache_read_alloc_page() and co with -ENOBUFS. + + + (*) Mark pages as being cached: + + void fscache_mark_pages_cached(struct fscache_retrieval *op, + struct pagevec *pagevec); + + This marks a set of pages as being cached. After this has been called, + the netfs must call fscache_uncache_page() to unmark the pages. + + + (*) Perform coherency check on an object: + + enum fscache_checkaux fscache_check_aux(struct fscache_object *object, + const void *data, + uint16_t datalen); + + This asks the netfs to perform a coherency check on an object that has + just been looked up. The cookie attached to the object will determine the + netfs to use. data and datalen should specify where the auxiliary data + retrieved from the cache can be found. + + One of three values will be returned: + + (*) FSCACHE_CHECKAUX_OKAY + + The coherency data indicates the object is valid as is. + + (*) FSCACHE_CHECKAUX_NEEDS_UPDATE + + The coherency data needs updating, but otherwise the object is + valid. + + (*) FSCACHE_CHECKAUX_OBSOLETE + + The coherency data indicates that the object is obsolete and should + be discarded. + + + (*) Initialise a freshly allocated object: + + void fscache_object_init(struct fscache_object *object); + + This initialises all the fields in an object representation. + + + (*) Indicate the destruction of an object: + + void fscache_object_destroyed(struct fscache_cache *cache); + + This must be called to inform FS-Cache that an object that belonged to a + cache has been destroyed and deallocated. This will allow continuation + of the cache withdrawal process when it is stopped pending destruction of + all the objects. + + + (*) Indicate negative lookup on an object: + + void fscache_object_lookup_negative(struct fscache_object *object); + + This is called to indicate to FS-Cache that a lookup process for an object + found a negative result. + + This changes the state of an object to permit reads pending on lookup + completion to go off and start fetching data from the netfs server as it's + known at this point that there can't be any data in the cache. + + This may be called multiple times on an object. Only the first call is + significant - all subsequent calls are ignored. + + + (*) Indicate an object has been obtained: + + void fscache_obtained_object(struct fscache_object *object); + + This is called to indicate to FS-Cache that a lookup process for an object + produced a positive result, or that an object was created. This should + only be called once for any particular object. + + This changes the state of an object to indicate: + + (1) if no call to fscache_object_lookup_negative() has been made on + this object, that there may be data available, and that reads can + now go and look for it; and + + (2) that writes may now proceed against this object. + + + (*) Indicate that object lookup failed: + + void fscache_object_lookup_error(struct fscache_object *object); + + This marks an object as having encountered a fatal error (usually EIO) + and causes it to move into a state whereby it will be withdrawn as soon + as possible. + + + (*) Get and release references on a retrieval record: + + void fscache_get_retrieval(struct fscache_retrieval *op); + void fscache_put_retrieval(struct fscache_retrieval *op); + + These two functions are used to retain a retrieval record whilst doing + asynchronous data retrieval and block allocation. + + + (*) Enqueue a retrieval record for processing. + + void fscache_enqueue_retrieval(struct fscache_retrieval *op); + + This enqueues a retrieval record for processing by the FS-Cache thread + pool. One of the threads in the pool will invoke the retrieval record's + op->op.processor callback function. This function may be called from + within the callback function. + + + (*) List of object state names: + + const char *fscache_object_states[]; + + For debugging purposes, this may be used to turn the state that an object + is in into a text string for display purposes. -- cgit v1.2.3 From 7394daa8c61dfda4baa687f133748fa0b599b017 Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 3 Apr 2009 16:42:37 +0100 Subject: FS-Cache: Add use of /proc and presentation of statistics Make FS-Cache create its /proc interface and present various statistical information through it. Also provide the functions for updating this information. These features are enabled by: CONFIG_FSCACHE_PROC CONFIG_FSCACHE_STATS CONFIG_FSCACHE_HISTOGRAM The /proc directory for FS-Cache is also exported so that caching modules can add their own statistics there too. The FS-Cache module is loadable at this point, and the statistics files can be examined by userspace: cat /proc/fs/fscache/stats cat /proc/fs/fscache/histogram Signed-off-by: David Howells Acked-by: Steve Dickson Acked-by: Trond Myklebust Acked-by: Al Viro Tested-by: Daire Byrne --- Documentation/filesystems/caching/backend-api.txt | 6 ------ Documentation/filesystems/caching/fscache.txt | 12 +++++------- 2 files changed, 5 insertions(+), 13 deletions(-) (limited to 'Documentation') diff --git a/Documentation/filesystems/caching/backend-api.txt b/Documentation/filesystems/caching/backend-api.txt index 17723053aa9..382d52cdaf2 100644 --- a/Documentation/filesystems/caching/backend-api.txt +++ b/Documentation/filesystems/caching/backend-api.txt @@ -100,12 +100,6 @@ A sysfs directory called /sys/fs/fscache// is created if CONFIG_SYSFS is enabled. This is accessible through the kobject struct fscache_cache::kobj and is for use by the cache as it sees fit. -The cache driver may create itself a directory named for the cache type in the -/proc/fs/fscache/ directory. This is available if CONFIG_FSCACHE_PROC is -enabled and is accessible through: - - struct proc_dir_entry *proc_fscache; - ======================== RELEVANT DATA STRUCTURES diff --git a/Documentation/filesystems/caching/fscache.txt b/Documentation/filesystems/caching/fscache.txt index a759d916273..0a751f3c2c7 100644 --- a/Documentation/filesystems/caching/fscache.txt +++ b/Documentation/filesystems/caching/fscache.txt @@ -195,7 +195,6 @@ STATISTICAL INFORMATION If FS-Cache is compiled with the following options enabled: - CONFIG_FSCACHE_PROC=y (implied by the following two) CONFIG_FSCACHE_STATS=y CONFIG_FSCACHE_HISTOGRAM=y @@ -275,7 +274,7 @@ proc files. (*) /proc/fs/fscache/histogram cat /proc/fs/fscache/histogram - +HZ +TIME OBJ INST OP RUNS OBJ RUNS RETRV DLY RETRIEVLS + JIFS SECS OBJ INST OP RUNS OBJ RUNS RETRV DLY RETRIEVLS ===== ===== ========= ========= ========= ========= ========= This shows the breakdown of the number of times each amount of time @@ -291,16 +290,16 @@ proc files. RETRIEVLS Time between beginning and end of a retrieval Each row shows the number of events that took a particular range of times. - Each step is 1 jiffy in size. The +HZ column indicates the particular - jiffy range covered, and the +TIME field the equivalent number of seconds. + Each step is 1 jiffy in size. The JIFS column indicates the particular + jiffy range covered, and the SECS field the equivalent number of seconds. ========= DEBUGGING ========= -The FS-Cache facility can have runtime debugging enabled by adjusting the value -in: +If CONFIG_FSCACHE_DEBUG is enabled, the FS-Cache facility can have runtime +debugging enabled by adjusting the value in: /sys/module/fscache/parameters/debug @@ -327,4 +326,3 @@ the control file. For example: echo $((1|8|64)) >/sys/module/fscache/parameters/debug will turn on all function entry debugging. - -- cgit v1.2.3 From 36c9559022850f919269564a74bf17fdabf4bb30 Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 3 Apr 2009 16:42:38 +0100 Subject: FS-Cache: Object management state machine Implement the cache object management state machine. The following documentation is added to illuminate the working of this state machine. It will also be added as: Documentation/filesystems/caching/object.txt ==================================================== IN-KERNEL CACHE OBJECT REPRESENTATION AND MANAGEMENT ==================================================== ============== REPRESENTATION ============== FS-Cache maintains an in-kernel representation of each object that a netfs is currently interested in. Such objects are represented by the fscache_cookie struct and are referred to as cookies. FS-Cache also maintains a separate in-kernel representation of the objects that a cache backend is currently actively caching. Such objects are represented by the fscache_object struct. The cache backends allocate these upon request, and are expected to embed them in their own representations. These are referred to as objects. There is a 1:N relationship between cookies and objects. A cookie may be represented by multiple objects - an index may exist in more than one cache - or even by no objects (it may not be cached). Furthermore, both cookies and objects are hierarchical. The two hierarchies correspond, but the cookies tree is a superset of the union of the object trees of multiple caches: NETFS INDEX TREE : CACHE 1 : CACHE 2 : : : +-----------+ : +----------->| IObject | : +-----------+ | : +-----------+ : | ICookie |-------+ : | : +-----------+ | : | : +-----------+ | +------------------------------>| IObject | | : | : +-----------+ | : V : | | : +-----------+ : | V +----------->| IObject | : | +-----------+ | : +-----------+ : | | ICookie |-------+ : | : V +-----------+ | : | : +-----------+ | +------------------------------>| IObject | +-----+-----+ : | : +-----------+ | | : | : | V | : V : | +-----------+ | : +-----------+ : | | ICookie |------------------------->| IObject | : | +-----------+ | : +-----------+ : | | V : | : V | +-----------+ : | : +-----------+ | | ICookie |-------------------------------->| IObject | | +-----------+ : | : +-----------+ V | : V : | +-----------+ | : +-----------+ : | | DCookie |------------------------->| DObject | : | +-----------+ | : +-----------+ : | | : : | +-------+-------+ : : | | | : : | V V : : V +-----------+ +-----------+ : : +-----------+ | DCookie | | DCookie |------------------------>| DObject | +-----------+ +-----------+ : : +-----------+ : : In the above illustration, ICookie and IObject represent indices and DCookie and DObject represent data storage objects. Indices may have representation in multiple caches, but currently, non-index objects may not. Objects of any type may also be entirely unrepresented. As far as the netfs API goes, the netfs is only actually permitted to see pointers to the cookies. The cookies themselves and any objects attached to those cookies are hidden from it. =============================== OBJECT MANAGEMENT STATE MACHINE =============================== Within FS-Cache, each active object is managed by its own individual state machine. The state for an object is kept in the fscache_object struct, in object->state. A cookie may point to a set of objects that are in different states. Each state has an action associated with it that is invoked when the machine wakes up in that state. There are four logical sets of states: (1) Preparation: states that wait for the parent objects to become ready. The representations are hierarchical, and it is expected that an object must be created or accessed with respect to its parent object. (2) Initialisation: states that perform lookups in the cache and validate what's found and that create on disk any missing metadata. (3) Normal running: states that allow netfs operations on objects to proceed and that update the state of objects. (4) Termination: states that detach objects from their netfs cookies, that delete objects from disk, that handle disk and system errors and that free up in-memory resources. In most cases, transitioning between states is in response to signalled events. When a state has finished processing, it will usually set the mask of events in which it is interested (object->event_mask) and relinquish the worker thread. Then when an event is raised (by calling fscache_raise_event()), if the event is not masked, the object will be queued for processing (by calling fscache_enqueue_object()). PROVISION OF CPU TIME --------------------- The work to be done by the various states is given CPU time by the threads of the slow work facility (see Documentation/slow-work.txt). This is used in preference to the workqueue facility because: (1) Threads may be completely occupied for very long periods of time by a particular work item. These state actions may be doing sequences of synchronous, journalled disk accesses (lookup, mkdir, create, setxattr, getxattr, truncate, unlink, rmdir, rename). (2) Threads may do little actual work, but may rather spend a lot of time sleeping on I/O. This means that single-threaded and 1-per-CPU-threaded workqueues don't necessarily have the right numbers of threads. LOCKING SIMPLIFICATION ---------------------- Because only one worker thread may be operating on any particular object's state machine at once, this simplifies the locking, particularly with respect to disconnecting the netfs's representation of a cache object (fscache_cookie) from the cache backend's representation (fscache_object) - which may be requested from either end. ================= THE SET OF STATES ================= The object state machine has a set of states that it can be in. There are preparation states in which the object sets itself up and waits for its parent object to transit to a state that allows access to its children: (1) State FSCACHE_OBJECT_INIT. Initialise the object and wait for the parent object to become active. In the cache, it is expected that it will not be possible to look an object up from the parent object, until that parent object itself has been looked up. There are initialisation states in which the object sets itself up and accesses disk for the object metadata: (2) State FSCACHE_OBJECT_LOOKING_UP. Look up the object on disk, using the parent as a starting point. FS-Cache expects the cache backend to probe the cache to see whether this object is represented there, and if it is, to see if it's valid (coherency management). The cache should call fscache_object_lookup_negative() to indicate lookup failure for whatever reason, and should call fscache_obtained_object() to indicate success. At the completion of lookup, FS-Cache will let the netfs go ahead with read operations, no matter whether the file is yet cached. If not yet cached, read operations will be immediately rejected with ENODATA until the first known page is uncached - as to that point there can be no data to be read out of the cache for that file that isn't currently also held in the pagecache. (3) State FSCACHE_OBJECT_CREATING. Create an object on disk, using the parent as a starting point. This happens if the lookup failed to find the object, or if the object's coherency data indicated what's on disk is out of date. In this state, FS-Cache expects the cache to create The cache should call fscache_obtained_object() if creation completes successfully, fscache_object_lookup_negative() otherwise. At the completion of creation, FS-Cache will start processing write operations the netfs has queued for an object. If creation failed, the write ops will be transparently discarded, and nothing recorded in the cache. There are some normal running states in which the object spends its time servicing netfs requests: (4) State FSCACHE_OBJECT_AVAILABLE. A transient state in which pending operations are started, child objects are permitted to advance from FSCACHE_OBJECT_INIT state, and temporary lookup data is freed. (5) State FSCACHE_OBJECT_ACTIVE. The normal running state. In this state, requests the netfs makes will be passed on to the cache. (6) State FSCACHE_OBJECT_UPDATING. The state machine comes here to update the object in the cache from the netfs's records. This involves updating the auxiliary data that is used to maintain coherency. And there are terminal states in which an object cleans itself up, deallocates memory and potentially deletes stuff from disk: (7) State FSCACHE_OBJECT_LC_DYING. The object comes here if it is dying because of a lookup or creation error. This would be due to a disk error or system error of some sort. Temporary data is cleaned up, and the parent is released. (8) State FSCACHE_OBJECT_DYING. The object comes here if it is dying due to an error, because its parent cookie has been relinquished by the netfs or because the cache is being withdrawn. Any child objects waiting on this one are given CPU time so that they too can destroy themselves. This object waits for all its children to go away before advancing to the next state. (9) State FSCACHE_OBJECT_ABORT_INIT. The object comes to this state if it was waiting on its parent in FSCACHE_OBJECT_INIT, but its parent died. The object will destroy itself so that the parent may proceed from the FSCACHE_OBJECT_DYING state. (10) State FSCACHE_OBJECT_RELEASING. (11) State FSCACHE_OBJECT_RECYCLING. The object comes to one of these two states when dying once it is rid of all its children, if it is dying because the netfs relinquished its cookie. In the first state, the cached data is expected to persist, and in the second it will be deleted. (12) State FSCACHE_OBJECT_WITHDRAWING. The object transits to this state if the cache decides it wants to withdraw the object from service, perhaps to make space, but also due to error or just because the whole cache is being withdrawn. (13) State FSCACHE_OBJECT_DEAD. The object transits to this state when the in-memory object record is ready to be deleted. The object processor shouldn't ever see an object in this state. THE SET OF EVENTS ----------------- There are a number of events that can be raised to an object state machine: (*) FSCACHE_OBJECT_EV_UPDATE The netfs requested that an object be updated. The state machine will ask the cache backend to update the object, and the cache backend will ask the netfs for details of the change through its cookie definition ops. (*) FSCACHE_OBJECT_EV_CLEARED This is signalled in two circumstances: (a) when an object's last child object is dropped and (b) when the last operation outstanding on an object is completed. This is used to proceed from the dying state. (*) FSCACHE_OBJECT_EV_ERROR This is signalled when an I/O error occurs during the processing of some object. (*) FSCACHE_OBJECT_EV_RELEASE (*) FSCACHE_OBJECT_EV_RETIRE These are signalled when the netfs relinquishes a cookie it was using. The event selected depends on whether the netfs asks for the backing object to be retired (deleted) or retained. (*) FSCACHE_OBJECT_EV_WITHDRAW This is signalled when the cache backend wants to withdraw an object. This means that the object will have to be detached from the netfs's cookie. Because the withdrawing releasing/retiring events are all handled by the object state machine, it doesn't matter if there's a collision with both ends trying to sever the connection at the same time. The state machine can just pick which one it wants to honour, and that effects the other. Signed-off-by: David Howells Acked-by: Steve Dickson Acked-by: Trond Myklebust Acked-by: Al Viro Tested-by: Daire Byrne --- Documentation/filesystems/caching/fscache.txt | 5 + Documentation/filesystems/caching/object.txt | 313 ++++++++++++++++++++++++++ 2 files changed, 318 insertions(+) create mode 100644 Documentation/filesystems/caching/object.txt (limited to 'Documentation') diff --git a/Documentation/filesystems/caching/fscache.txt b/Documentation/filesystems/caching/fscache.txt index 0a751f3c2c7..9e94b9491d8 100644 --- a/Documentation/filesystems/caching/fscache.txt +++ b/Documentation/filesystems/caching/fscache.txt @@ -188,6 +188,11 @@ The cache backend API to FS-Cache can be found in: Documentation/filesystems/caching/backend-api.txt +A description of the internal representations and object state machine can be +found in: + + Documentation/filesystems/caching/object.txt + ======================= STATISTICAL INFORMATION diff --git a/Documentation/filesystems/caching/object.txt b/Documentation/filesystems/caching/object.txt new file mode 100644 index 00000000000..e8b0a35d8fe --- /dev/null +++ b/Documentation/filesystems/caching/object.txt @@ -0,0 +1,313 @@ + ==================================================== + IN-KERNEL CACHE OBJECT REPRESENTATION AND MANAGEMENT + ==================================================== + +By: David Howells + +Contents: + + (*) Representation + + (*) Object management state machine. + + - Provision of cpu time. + - Locking simplification. + + (*) The set of states. + + (*) The set of events. + + +============== +REPRESENTATION +============== + +FS-Cache maintains an in-kernel representation of each object that a netfs is +currently interested in. Such objects are represented by the fscache_cookie +struct and are referred to as cookies. + +FS-Cache also maintains a separate in-kernel representation of the objects that +a cache backend is currently actively caching. Such objects are represented by +the fscache_object struct. The cache backends allocate these upon request, and +are expected to embed them in their own representations. These are referred to +as objects. + +There is a 1:N relationship between cookies and objects. A cookie may be +represented by multiple objects - an index may exist in more than one cache - +or even by no objects (it may not be cached). + +Furthermore, both cookies and objects are hierarchical. The two hierarchies +correspond, but the cookies tree is a superset of the union of the object trees +of multiple caches: + + NETFS INDEX TREE : CACHE 1 : CACHE 2 + : : + : +-----------+ : + +----------->| IObject | : + +-----------+ | : +-----------+ : + | ICookie |-------+ : | : + +-----------+ | : | : +-----------+ + | +------------------------------>| IObject | + | : | : +-----------+ + | : V : | + | : +-----------+ : | + V +----------->| IObject | : | + +-----------+ | : +-----------+ : | + | ICookie |-------+ : | : V + +-----------+ | : | : +-----------+ + | +------------------------------>| IObject | + +-----+-----+ : | : +-----------+ + | | : | : | + V | : V : | + +-----------+ | : +-----------+ : | + | ICookie |------------------------->| IObject | : | + +-----------+ | : +-----------+ : | + | V : | : V + | +-----------+ : | : +-----------+ + | | ICookie |-------------------------------->| IObject | + | +-----------+ : | : +-----------+ + V | : V : | + +-----------+ | : +-----------+ : | + | DCookie |------------------------->| DObject | : | + +-----------+ | : +-----------+ : | + | : : | + +-------+-------+ : : | + | | : : | + V V : : V + +-----------+ +-----------+ : : +-----------+ + | DCookie | | DCookie |------------------------>| DObject | + +-----------+ +-----------+ : : +-----------+ + : : + +In the above illustration, ICookie and IObject represent indices and DCookie +and DObject represent data storage objects. Indices may have representation in +multiple caches, but currently, non-index objects may not. Objects of any type +may also be entirely unrepresented. + +As far as the netfs API goes, the netfs is only actually permitted to see +pointers to the cookies. The cookies themselves and any objects attached to +those cookies are hidden from it. + + +=============================== +OBJECT MANAGEMENT STATE MACHINE +=============================== + +Within FS-Cache, each active object is managed by its own individual state +machine. The state for an object is kept in the fscache_object struct, in +object->state. A cookie may point to a set of objects that are in different +states. + +Each state has an action associated with it that is invoked when the machine +wakes up in that state. There are four logical sets of states: + + (1) Preparation: states that wait for the parent objects to become ready. The + representations are hierarchical, and it is expected that an object must + be created or accessed with respect to its parent object. + + (2) Initialisation: states that perform lookups in the cache and validate + what's found and that create on disk any missing metadata. + + (3) Normal running: states that allow netfs operations on objects to proceed + and that update the state of objects. + + (4) Termination: states that detach objects from their netfs cookies, that + delete objects from disk, that handle disk and system errors and that free + up in-memory resources. + + +In most cases, transitioning between states is in response to signalled events. +When a state has finished processing, it will usually set the mask of events in +which it is interested (object->event_mask) and relinquish the worker thread. +Then when an event is raised (by calling fscache_raise_event()), if the event +is not masked, the object will be queued for processing (by calling +fscache_enqueue_object()). + + +PROVISION OF CPU TIME +--------------------- + +The work to be done by the various states is given CPU time by the threads of +the slow work facility (see Documentation/slow-work.txt). This is used in +preference to the workqueue facility because: + + (1) Threads may be completely occupied for very long periods of time by a + particular work item. These state actions may be doing sequences of + synchronous, journalled disk accesses (lookup, mkdir, create, setxattr, + getxattr, truncate, unlink, rmdir, rename). + + (2) Threads may do little actual work, but may rather spend a lot of time + sleeping on I/O. This means that single-threaded and 1-per-CPU-threaded + workqueues don't necessarily have the right numbers of threads. + + +LOCKING SIMPLIFICATION +---------------------- + +Because only one worker thread may be operating on any particular object's +state machine at once, this simplifies the locking, particularly with respect +to disconnecting the netfs's representation of a cache object (fscache_cookie) +from the cache backend's representation (fscache_object) - which may be +requested from either end. + + +================= +THE SET OF STATES +================= + +The object state machine has a set of states that it can be in. There are +preparation states in which the object sets itself up and waits for its parent +object to transit to a state that allows access to its children: + + (1) State FSCACHE_OBJECT_INIT. + + Initialise the object and wait for the parent object to become active. In + the cache, it is expected that it will not be possible to look an object + up from the parent object, until that parent object itself has been looked + up. + +There are initialisation states in which the object sets itself up and accesses +disk for the object metadata: + + (2) State FSCACHE_OBJECT_LOOKING_UP. + + Look up the object on disk, using the parent as a starting point. + FS-Cache expects the cache backend to probe the cache to see whether this + object is represented there, and if it is, to see if it's valid (coherency + management). + + The cache should call fscache_object_lookup_negative() to indicate lookup + failure for whatever reason, and should call fscache_obtained_object() to + indicate success. + + At the completion of lookup, FS-Cache will let the netfs go ahead with + read operations, no matter whether the file is yet cached. If not yet + cached, read operations will be immediately rejected with ENODATA until + the first known page is uncached - as to that point there can be no data + to be read out of the cache for that file that isn't currently also held + in the pagecache. + + (3) State FSCACHE_OBJECT_CREATING. + + Create an object on disk, using the parent as a starting point. This + happens if the lookup failed to find the object, or if the object's + coherency data indicated what's on disk is out of date. In this state, + FS-Cache expects the cache to create + + The cache should call fscache_obtained_object() if creation completes + successfully, fscache_object_lookup_negative() otherwise. + + At the completion of creation, FS-Cache will start processing write + operations the netfs has queued for an object. If creation failed, the + write ops will be transparently discarded, and nothing recorded in the + cache. + +There are some normal running states in which the object spends its time +servicing netfs requests: + + (4) State FSCACHE_OBJECT_AVAILABLE. + + A transient state in which pending operations are started, child objects + are permitted to advance from FSCACHE_OBJECT_INIT state, and temporary + lookup data is freed. + + (5) State FSCACHE_OBJECT_ACTIVE. + + The normal running state. In this state, requests the netfs makes will be + passed on to the cache. + + (6) State FSCACHE_OBJECT_UPDATING. + + The state machine comes here to update the object in the cache from the + netfs's records. This involves updating the auxiliary data that is used + to maintain coherency. + +And there are terminal states in which an object cleans itself up, deallocates +memory and potentially deletes stuff from disk: + + (7) State FSCACHE_OBJECT_LC_DYING. + + The object comes here if it is dying because of a lookup or creation + error. This would be due to a disk error or system error of some sort. + Temporary data is cleaned up, and the parent is released. + + (8) State FSCACHE_OBJECT_DYING. + + The object comes here if it is dying due to an error, because its parent + cookie has been relinquished by the netfs or because the cache is being + withdrawn. + + Any child objects waiting on this one are given CPU time so that they too + can destroy themselves. This object waits for all its children to go away + before advancing to the next state. + + (9) State FSCACHE_OBJECT_ABORT_INIT. + + The object comes to this state if it was waiting on its parent in + FSCACHE_OBJECT_INIT, but its parent died. The object will destroy itself + so that the parent may proceed from the FSCACHE_OBJECT_DYING state. + +(10) State FSCACHE_OBJECT_RELEASING. +(11) State FSCACHE_OBJECT_RECYCLING. + + The object comes to one of these two states when dying once it is rid of + all its children, if it is dying because the netfs relinquished its + cookie. In the first state, the cached data is expected to persist, and + in the second it will be deleted. + +(12) State FSCACHE_OBJECT_WITHDRAWING. + + The object transits to this state if the cache decides it wants to + withdraw the object from service, perhaps to make space, but also due to + error or just because the whole cache is being withdrawn. + +(13) State FSCACHE_OBJECT_DEAD. + + The object transits to this state when the in-memory object record is + ready to be deleted. The object processor shouldn't ever see an object in + this state. + + +THE SET OF EVENTS +----------------- + +There are a number of events that can be raised to an object state machine: + + (*) FSCACHE_OBJECT_EV_UPDATE + + The netfs requested that an object be updated. The state machine will ask + the cache backend to update the object, and the cache backend will ask the + netfs for details of the change through its cookie definition ops. + + (*) FSCACHE_OBJECT_EV_CLEARED + + This is signalled in two circumstances: + + (a) when an object's last child object is dropped and + + (b) when the last operation outstanding on an object is completed. + + This is used to proceed from the dying state. + + (*) FSCACHE_OBJECT_EV_ERROR + + This is signalled when an I/O error occurs during the processing of some + object. + + (*) FSCACHE_OBJECT_EV_RELEASE + (*) FSCACHE_OBJECT_EV_RETIRE + + These are signalled when the netfs relinquishes a cookie it was using. + The event selected depends on whether the netfs asks for the backing + object to be retired (deleted) or retained. + + (*) FSCACHE_OBJECT_EV_WITHDRAW + + This is signalled when the cache backend wants to withdraw an object. + This means that the object will have to be detached from the netfs's + cookie. + +Because the withdrawing releasing/retiring events are all handled by the object +state machine, it doesn't matter if there's a collision with both ends trying +to sever the connection at the same time. The state machine can just pick +which one it wants to honour, and that effects the other. -- cgit v1.2.3 From 952efe7b7840e1c726ae88222245e4efe6bd88f3 Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 3 Apr 2009 16:42:39 +0100 Subject: FS-Cache: Add and document asynchronous operation handling Add and document asynchronous operation handling for use by FS-Cache's data storage and retrieval routines. The following documentation is added to: Documentation/filesystems/caching/operations.txt ================================ ASYNCHRONOUS OPERATIONS HANDLING ================================ ======== OVERVIEW ======== FS-Cache has an asynchronous operations handling facility that it uses for its data storage and retrieval routines. Its operations are represented by fscache_operation structs, though these are usually embedded into some other structure. This facility is available to and expected to be be used by the cache backends, and FS-Cache will create operations and pass them off to the appropriate cache backend for completion. To make use of this facility, should be #included. =============================== OPERATION RECORD INITIALISATION =============================== An operation is recorded in an fscache_operation struct: struct fscache_operation { union { struct work_struct fast_work; struct slow_work slow_work; }; unsigned long flags; fscache_operation_processor_t processor; ... }; Someone wanting to issue an operation should allocate something with this struct embedded in it. They should initialise it by calling: void fscache_operation_init(struct fscache_operation *op, fscache_operation_release_t release); with the operation to be initialised and the release function to use. The op->flags parameter should be set to indicate the CPU time provision and the exclusivity (see the Parameters section). The op->fast_work, op->slow_work and op->processor flags should be set as appropriate for the CPU time provision (see the Parameters section). FSCACHE_OP_WAITING may be set in op->flags prior to each submission of the operation and waited for afterwards. ========== PARAMETERS ========== There are a number of parameters that can be set in the operation record's flag parameter. There are three options for the provision of CPU time in these operations: (1) The operation may be done synchronously (FSCACHE_OP_MYTHREAD). A thread may decide it wants to handle an operation itself without deferring it to another thread. This is, for example, used in read operations for calling readpages() on the backing filesystem in CacheFiles. Although readpages() does an asynchronous data fetch, the determination of whether pages exist is done synchronously - and the netfs does not proceed until this has been determined. If this option is to be used, FSCACHE_OP_WAITING must be set in op->flags before submitting the operation, and the operating thread must wait for it to be cleared before proceeding: wait_on_bit(&op->flags, FSCACHE_OP_WAITING, fscache_wait_bit, TASK_UNINTERRUPTIBLE); (2) The operation may be fast asynchronous (FSCACHE_OP_FAST), in which case it will be given to keventd to process. Such an operation is not permitted to sleep on I/O. This is, for example, used by CacheFiles to copy data from a backing fs page to a netfs page after the backing fs has read the page in. If this option is used, op->fast_work and op->processor must be initialised before submitting the operation: INIT_WORK(&op->fast_work, do_some_work); (3) The operation may be slow asynchronous (FSCACHE_OP_SLOW), in which case it will be given to the slow work facility to process. Such an operation is permitted to sleep on I/O. This is, for example, used by FS-Cache to handle background writes of pages that have just been fetched from a remote server. If this option is used, op->slow_work and op->processor must be initialised before submitting the operation: fscache_operation_init_slow(op, processor) Furthermore, operations may be one of two types: (1) Exclusive (FSCACHE_OP_EXCLUSIVE). Operations of this type may not run in conjunction with any other operation on the object being operated upon. An example of this is the attribute change operation, in which the file being written to may need truncation. (2) Shareable. Operations of this type may be running simultaneously. It's up to the operation implementation to prevent interference between other operations running at the same time. ========= PROCEDURE ========= Operations are used through the following procedure: (1) The submitting thread must allocate the operation and initialise it itself. Normally this would be part of a more specific structure with the generic op embedded within. (2) The submitting thread must then submit the operation for processing using one of the following two functions: int fscache_submit_op(struct fscache_object *object, struct fscache_operation *op); int fscache_submit_exclusive_op(struct fscache_object *object, struct fscache_operation *op); The first function should be used to submit non-exclusive ops and the second to submit exclusive ones. The caller must still set the FSCACHE_OP_EXCLUSIVE flag. If successful, both functions will assign the operation to the specified object and return 0. -ENOBUFS will be returned if the object specified is permanently unavailable. The operation manager will defer operations on an object that is still undergoing lookup or creation. The operation will also be deferred if an operation of conflicting exclusivity is in progress on the object. If the operation is asynchronous, the manager will retain a reference to it, so the caller should put their reference to it by passing it to: void fscache_put_operation(struct fscache_operation *op); (3) If the submitting thread wants to do the work itself, and has marked the operation with FSCACHE_OP_MYTHREAD, then it should monitor FSCACHE_OP_WAITING as described above and check the state of the object if necessary (the object might have died whilst the thread was waiting). When it has finished doing its processing, it should call fscache_put_operation() on it. (4) The operation holds an effective lock upon the object, preventing other exclusive ops conflicting until it is released. The operation can be enqueued for further immediate asynchronous processing by adjusting the CPU time provisioning option if necessary, eg: op->flags &= ~FSCACHE_OP_TYPE; op->flags |= ~FSCACHE_OP_FAST; and calling: void fscache_enqueue_operation(struct fscache_operation *op) This can be used to allow other things to have use of the worker thread pools. ===================== ASYNCHRONOUS CALLBACK ===================== When used in asynchronous mode, the worker thread pool will invoke the processor method with a pointer to the operation. This should then get at the container struct by using container_of(): static void fscache_write_op(struct fscache_operation *_op) { struct fscache_storage *op = container_of(_op, struct fscache_storage, op); ... } The caller holds a reference on the operation, and will invoke fscache_put_operation() when the processor function returns. The processor function is at liberty to call fscache_enqueue_operation() or to take extra references. Signed-off-by: David Howells Acked-by: Steve Dickson Acked-by: Trond Myklebust Acked-by: Al Viro Tested-by: Daire Byrne --- Documentation/filesystems/caching/operations.txt | 213 +++++++++++++++++++++++ 1 file changed, 213 insertions(+) create mode 100644 Documentation/filesystems/caching/operations.txt (limited to 'Documentation') diff --git a/Documentation/filesystems/caching/operations.txt b/Documentation/filesystems/caching/operations.txt new file mode 100644 index 00000000000..b6b070c57cb --- /dev/null +++ b/Documentation/filesystems/caching/operations.txt @@ -0,0 +1,213 @@ + ================================ + ASYNCHRONOUS OPERATIONS HANDLING + ================================ + +By: David Howells + +Contents: + + (*) Overview. + + (*) Operation record initialisation. + + (*) Parameters. + + (*) Procedure. + + (*) Asynchronous callback. + + +======== +OVERVIEW +======== + +FS-Cache has an asynchronous operations handling facility that it uses for its +data storage and retrieval routines. Its operations are represented by +fscache_operation structs, though these are usually embedded into some other +structure. + +This facility is available to and expected to be be used by the cache backends, +and FS-Cache will create operations and pass them off to the appropriate cache +backend for completion. + +To make use of this facility, should be #included. + + +=============================== +OPERATION RECORD INITIALISATION +=============================== + +An operation is recorded in an fscache_operation struct: + + struct fscache_operation { + union { + struct work_struct fast_work; + struct slow_work slow_work; + }; + unsigned long flags; + fscache_operation_processor_t processor; + ... + }; + +Someone wanting to issue an operation should allocate something with this +struct embedded in it. They should initialise it by calling: + + void fscache_operation_init(struct fscache_operation *op, + fscache_operation_release_t release); + +with the operation to be initialised and the release function to use. + +The op->flags parameter should be set to indicate the CPU time provision and +the exclusivity (see the Parameters section). + +The op->fast_work, op->slow_work and op->processor flags should be set as +appropriate for the CPU time provision (see the Parameters section). + +FSCACHE_OP_WAITING may be set in op->flags prior to each submission of the +operation and waited for afterwards. + + +========== +PARAMETERS +========== + +There are a number of parameters that can be set in the operation record's flag +parameter. There are three options for the provision of CPU time in these +operations: + + (1) The operation may be done synchronously (FSCACHE_OP_MYTHREAD). A thread + may decide it wants to handle an operation itself without deferring it to + another thread. + + This is, for example, used in read operations for calling readpages() on + the backing filesystem in CacheFiles. Although readpages() does an + asynchronous data fetch, the determination of whether pages exist is done + synchronously - and the netfs does not proceed until this has been + determined. + + If this option is to be used, FSCACHE_OP_WAITING must be set in op->flags + before submitting the operation, and the operating thread must wait for it + to be cleared before proceeding: + + wait_on_bit(&op->flags, FSCACHE_OP_WAITING, + fscache_wait_bit, TASK_UNINTERRUPTIBLE); + + + (2) The operation may be fast asynchronous (FSCACHE_OP_FAST), in which case it + will be given to keventd to process. Such an operation is not permitted + to sleep on I/O. + + This is, for example, used by CacheFiles to copy data from a backing fs + page to a netfs page after the backing fs has read the page in. + + If this option is used, op->fast_work and op->processor must be + initialised before submitting the operation: + + INIT_WORK(&op->fast_work, do_some_work); + + + (3) The operation may be slow asynchronous (FSCACHE_OP_SLOW), in which case it + will be given to the slow work facility to process. Such an operation is + permitted to sleep on I/O. + + This is, for example, used by FS-Cache to handle background writes of + pages that have just been fetched from a remote server. + + If this option is used, op->slow_work and op->processor must be + initialised before submitting the operation: + + fscache_operation_init_slow(op, processor) + + +Furthermore, operations may be one of two types: + + (1) Exclusive (FSCACHE_OP_EXCLUSIVE). Operations of this type may not run in + conjunction with any other operation on the object being operated upon. + + An example of this is the attribute change operation, in which the file + being written to may need truncation. + + (2) Shareable. Operations of this type may be running simultaneously. It's + up to the operation implementation to prevent interference between other + operations running at the same time. + + +========= +PROCEDURE +========= + +Operations are used through the following procedure: + + (1) The submitting thread must allocate the operation and initialise it + itself. Normally this would be part of a more specific structure with the + generic op embedded within. + + (2) The submitting thread must then submit the operation for processing using + one of the following two functions: + + int fscache_submit_op(struct fscache_object *object, + struct fscache_operation *op); + + int fscache_submit_exclusive_op(struct fscache_object *object, + struct fscache_operation *op); + + The first function should be used to submit non-exclusive ops and the + second to submit exclusive ones. The caller must still set the + FSCACHE_OP_EXCLUSIVE flag. + + If successful, both functions will assign the operation to the specified + object and return 0. -ENOBUFS will be returned if the object specified is + permanently unavailable. + + The operation manager will defer operations on an object that is still + undergoing lookup or creation. The operation will also be deferred if an + operation of conflicting exclusivity is in progress on the object. + + If the operation is asynchronous, the manager will retain a reference to + it, so the caller should put their reference to it by passing it to: + + void fscache_put_operation(struct fscache_operation *op); + + (3) If the submitting thread wants to do the work itself, and has marked the + operation with FSCACHE_OP_MYTHREAD, then it should monitor + FSCACHE_OP_WAITING as described above and check the state of the object if + necessary (the object might have died whilst the thread was waiting). + + When it has finished doing its processing, it should call + fscache_put_operation() on it. + + (4) The operation holds an effective lock upon the object, preventing other + exclusive ops conflicting until it is released. The operation can be + enqueued for further immediate asynchronous processing by adjusting the + CPU time provisioning option if necessary, eg: + + op->flags &= ~FSCACHE_OP_TYPE; + op->flags |= ~FSCACHE_OP_FAST; + + and calling: + + void fscache_enqueue_operation(struct fscache_operation *op) + + This can be used to allow other things to have use of the worker thread + pools. + + +===================== +ASYNCHRONOUS CALLBACK +===================== + +When used in asynchronous mode, the worker thread pool will invoke the +processor method with a pointer to the operation. This should then get at the +container struct by using container_of(): + + static void fscache_write_op(struct fscache_operation *_op) + { + struct fscache_storage *op = + container_of(_op, struct fscache_storage, op); + ... + } + +The caller holds a reference on the operation, and will invoke +fscache_put_operation() when the processor function returns. The processor +function is at liberty to call fscache_enqueue_operation() or to take extra +references. -- cgit v1.2.3 From 9ae326a69004dea8af2dae4fde58de27db700a8d Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 3 Apr 2009 16:42:41 +0100 Subject: CacheFiles: A cache that backs onto a mounted filesystem Add an FS-Cache cache-backend that permits a mounted filesystem to be used as a backing store for the cache. CacheFiles uses a userspace daemon to do some of the cache management - such as reaping stale nodes and culling. This is called cachefilesd and lives in /sbin. The source for the daemon can be downloaded from: http://people.redhat.com/~dhowells/cachefs/cachefilesd.c And an example configuration from: http://people.redhat.com/~dhowells/cachefs/cachefilesd.conf The filesystem and data integrity of the cache are only as good as those of the filesystem providing the backing services. Note that CacheFiles does not attempt to journal anything since the journalling interfaces of the various filesystems are very specific in nature. CacheFiles creates a misc character device - "/dev/cachefiles" - that is used to communication with the daemon. Only one thing may have this open at once, and whilst it is open, a cache is at least partially in existence. The daemon opens this and sends commands down it to control the cache. CacheFiles is currently limited to a single cache. CacheFiles attempts to maintain at least a certain percentage of free space on the filesystem, shrinking the cache by culling the objects it contains to make space if necessary - see the "Cache Culling" section. This means it can be placed on the same medium as a live set of data, and will expand to make use of spare space and automatically contract when the set of data requires more space. ============ REQUIREMENTS ============ The use of CacheFiles and its daemon requires the following features to be available in the system and in the cache filesystem: - dnotify. - extended attributes (xattrs). - openat() and friends. - bmap() support on files in the filesystem (FIBMAP ioctl). - The use of bmap() to detect a partial page at the end of the file. It is strongly recommended that the "dir_index" option is enabled on Ext3 filesystems being used as a cache. ============= CONFIGURATION ============= The cache is configured by a script in /etc/cachefilesd.conf. These commands set up cache ready for use. The following script commands are available: (*) brun % (*) bcull % (*) bstop % (*) frun % (*) fcull % (*) fstop % Configure the culling limits. Optional. See the section on culling The defaults are 7% (run), 5% (cull) and 1% (stop) respectively. The commands beginning with a 'b' are file space (block) limits, those beginning with an 'f' are file count limits. (*) dir Specify the directory containing the root of the cache. Mandatory. (*) tag Specify a tag to FS-Cache to use in distinguishing multiple caches. Optional. The default is "CacheFiles". (*) debug Specify a numeric bitmask to control debugging in the kernel module. Optional. The default is zero (all off). The following values can be OR'd into the mask to collect various information: 1 Turn on trace of function entry (_enter() macros) 2 Turn on trace of function exit (_leave() macros) 4 Turn on trace of internal debug points (_debug()) This mask can also be set through sysfs, eg: echo 5 >/sys/modules/cachefiles/parameters/debug ================== STARTING THE CACHE ================== The cache is started by running the daemon. The daemon opens the cache device, configures the cache and tells it to begin caching. At that point the cache binds to fscache and the cache becomes live. The daemon is run as follows: /sbin/cachefilesd [-d]* [-s] [-n] [-f ] The flags are: (*) -d Increase the debugging level. This can be specified multiple times and is cumulative with itself. (*) -s Send messages to stderr instead of syslog. (*) -n Don't daemonise and go into background. (*) -f Use an alternative configuration file rather than the default one. =============== THINGS TO AVOID =============== Do not mount other things within the cache as this will cause problems. The kernel module contains its own very cut-down path walking facility that ignores mountpoints, but the daemon can't avoid them. Do not create, rename or unlink files and directories in the cache whilst the cache is active, as this may cause the state to become uncertain. Renaming files in the cache might make objects appear to be other objects (the filename is part of the lookup key). Do not change or remove the extended attributes attached to cache files by the cache as this will cause the cache state management to get confused. Do not create files or directories in the cache, lest the cache get confused or serve incorrect data. Do not chmod files in the cache. The module creates things with minimal permissions to prevent random users being able to access them directly. ============= CACHE CULLING ============= The cache may need culling occasionally to make space. This involves discarding objects from the cache that have been used less recently than anything else. Culling is based on the access time of data objects. Empty directories are culled if not in use. Cache culling is done on the basis of the percentage of blocks and the percentage of files available in the underlying filesystem. There are six "limits": (*) brun (*) frun If the amount of free space and the number of available files in the cache rises above both these limits, then culling is turned off. (*) bcull (*) fcull If the amount of available space or the number of available files in the cache falls below either of these limits, then culling is started. (*) bstop (*) fstop If the amount of available space or the number of available files in the cache falls below either of these limits, then no further allocation of disk space or files is permitted until culling has raised things above these limits again. These must be configured thusly: 0 <= bstop < bcull < brun < 100 0 <= fstop < fcull < frun < 100 Note that these are percentages of available space and available files, and do _not_ appear as 100 minus the percentage displayed by the "df" program. The userspace daemon scans the cache to build up a table of cullable objects. These are then culled in least recently used order. A new scan of the cache is started as soon as space is made in the table. Objects will be skipped if their atimes have changed or if the kernel module says it is still using them. =============== CACHE STRUCTURE =============== The CacheFiles module will create two directories in the directory it was given: (*) cache/ (*) graveyard/ The active cache objects all reside in the first directory. The CacheFiles kernel module moves any retired or culled objects that it can't simply unlink to the graveyard from which the daemon will actually delete them. The daemon uses dnotify to monitor the graveyard directory, and will delete anything that appears therein. The module represents index objects as directories with the filename "I..." or "J...". Note that the "cache/" directory is itself a special index. Data objects are represented as files if they have no children, or directories if they do. Their filenames all begin "D..." or "E...". If represented as a directory, data objects will have a file in the directory called "data" that actually holds the data. Special objects are similar to data objects, except their filenames begin "S..." or "T...". If an object has children, then it will be represented as a directory. Immediately in the representative directory are a collection of directories named for hash values of the child object keys with an '@' prepended. Into this directory, if possible, will be placed the representations of the child objects: INDEX INDEX INDEX DATA FILES ========= ========== ================================= ================ cache/@4a/I03nfs/@30/Ji000000000000000--fHg8hi8400 cache/@4a/I03nfs/@30/Ji000000000000000--fHg8hi8400/@75/Es0g000w...DB1ry cache/@4a/I03nfs/@30/Ji000000000000000--fHg8hi8400/@75/Es0g000w...N22ry cache/@4a/I03nfs/@30/Ji000000000000000--fHg8hi8400/@75/Es0g000w...FP1ry If the key is so long that it exceeds NAME_MAX with the decorations added on to it, then it will be cut into pieces, the first few of which will be used to make a nest of directories, and the last one of which will be the objects inside the last directory. The names of the intermediate directories will have '+' prepended: J1223/@23/+xy...z/+kl...m/Epqr Note that keys are raw data, and not only may they exceed NAME_MAX in size, they may also contain things like '/' and NUL characters, and so they may not be suitable for turning directly into a filename. To handle this, CacheFiles will use a suitably printable filename directly and "base-64" encode ones that aren't directly suitable. The two versions of object filenames indicate the encoding: OBJECT TYPE PRINTABLE ENCODED =============== =============== =============== Index "I..." "J..." Data "D..." "E..." Special "S..." "T..." Intermediate directories are always "@" or "+" as appropriate. Each object in the cache has an extended attribute label that holds the object type ID (required to distinguish special objects) and the auxiliary data from the netfs. The latter is used to detect stale objects in the cache and update or retire them. Note that CacheFiles will erase from the cache any file it doesn't recognise or any file of an incorrect type (such as a FIFO file or a device file). ========================== SECURITY MODEL AND SELINUX ========================== CacheFiles is implemented to deal properly with the LSM security features of the Linux kernel and the SELinux facility. One of the problems that CacheFiles faces is that it is generally acting on behalf of a process, and running in that process's context, and that includes a security context that is not appropriate for accessing the cache - either because the files in the cache are inaccessible to that process, or because if the process creates a file in the cache, that file may be inaccessible to other processes. The way CacheFiles works is to temporarily change the security context (fsuid, fsgid and actor security label) that the process acts as - without changing the security context of the process when it the target of an operation performed by some other process (so signalling and suchlike still work correctly). When the CacheFiles module is asked to bind to its cache, it: (1) Finds the security label attached to the root cache directory and uses that as the security label with which it will create files. By default, this is: cachefiles_var_t (2) Finds the security label of the process which issued the bind request (presumed to be the cachefilesd daemon), which by default will be: cachefilesd_t and asks LSM to supply a security ID as which it should act given the daemon's label. By default, this will be: cachefiles_kernel_t SELinux transitions the daemon's security ID to the module's security ID based on a rule of this form in the policy. type_transition kernel_t : process ; For instance: type_transition cachefilesd_t kernel_t : process cachefiles_kernel_t; The module's security ID gives it permission to create, move and remove files and directories in the cache, to find and access directories and files in the cache, to set and access extended attributes on cache objects, and to read and write files in the cache. The daemon's security ID gives it only a very restricted set of permissions: it may scan directories, stat files and erase files and directories. It may not read or write files in the cache, and so it is precluded from accessing the data cached therein; nor is it permitted to create new files in the cache. There are policy source files available in: http://people.redhat.com/~dhowells/fscache/cachefilesd-0.8.tar.bz2 and later versions. In that tarball, see the files: cachefilesd.te cachefilesd.fc cachefilesd.if They are built and installed directly by the RPM. If a non-RPM based system is being used, then copy the above files to their own directory and run: make -f /usr/share/selinux/devel/Makefile semodule -i cachefilesd.pp You will need checkpolicy and selinux-policy-devel installed prior to the build. By default, the cache is located in /var/fscache, but if it is desirable that it should be elsewhere, than either the above policy files must be altered, or an auxiliary policy must be installed to label the alternate location of the cache. For instructions on how to add an auxiliary policy to enable the cache to be located elsewhere when SELinux is in enforcing mode, please see: /usr/share/doc/cachefilesd-*/move-cache.txt When the cachefilesd rpm is installed; alternatively, the document can be found in the sources. ================== A NOTE ON SECURITY ================== CacheFiles makes use of the split security in the task_struct. It allocates its own task_security structure, and redirects current->act_as to point to it when it acts on behalf of another process, in that process's context. The reason it does this is that it calls vfs_mkdir() and suchlike rather than bypassing security and calling inode ops directly. Therefore the VFS and LSM may deny the CacheFiles access to the cache data because under some circumstances the caching code is running in the security context of whatever process issued the original syscall on the netfs. Furthermore, should CacheFiles create a file or directory, the security parameters with that object is created (UID, GID, security label) would be derived from that process that issued the system call, thus potentially preventing other processes from accessing the cache - including CacheFiles's cache management daemon (cachefilesd). What is required is to temporarily override the security of the process that issued the system call. We can't, however, just do an in-place change of the security data as that affects the process as an object, not just as a subject. This means it may lose signals or ptrace events for example, and affects what the process looks like in /proc. So CacheFiles makes use of a logical split in the security between the objective security (task->sec) and the subjective security (task->act_as). The objective security holds the intrinsic security properties of a process and is never overridden. This is what appears in /proc, and is what is used when a process is the target of an operation by some other process (SIGKILL for example). The subjective security holds the active security properties of a process, and may be overridden. This is not seen externally, and is used whan a process acts upon another object, for example SIGKILLing another process or opening a file. LSM hooks exist that allow SELinux (or Smack or whatever) to reject a request for CacheFiles to run in a context of a specific security label, or to create files and directories with another security label. This documentation is added by the patch to: Documentation/filesystems/caching/cachefiles.txt Signed-Off-By: David Howells Acked-by: Steve Dickson Acked-by: Trond Myklebust Acked-by: Al Viro Tested-by: Daire Byrne --- Documentation/filesystems/caching/cachefiles.txt | 501 +++++++++++++++++++++++ 1 file changed, 501 insertions(+) create mode 100644 Documentation/filesystems/caching/cachefiles.txt (limited to 'Documentation') diff --git a/Documentation/filesystems/caching/cachefiles.txt b/Documentation/filesystems/caching/cachefiles.txt new file mode 100644 index 00000000000..c78a49b7bba --- /dev/null +++ b/Documentation/filesystems/caching/cachefiles.txt @@ -0,0 +1,501 @@ + =============================================== + CacheFiles: CACHE ON ALREADY MOUNTED FILESYSTEM + =============================================== + +Contents: + + (*) Overview. + + (*) Requirements. + + (*) Configuration. + + (*) Starting the cache. + + (*) Things to avoid. + + (*) Cache culling. + + (*) Cache structure. + + (*) Security model and SELinux. + + (*) A note on security. + + (*) Statistical information. + + (*) Debugging. + + +======== +OVERVIEW +======== + +CacheFiles is a caching backend that's meant to use as a cache a directory on +an already mounted filesystem of a local type (such as Ext3). + +CacheFiles uses a userspace daemon to do some of the cache management - such as +reaping stale nodes and culling. This is called cachefilesd and lives in +/sbin. + +The filesystem and data integrity of the cache are only as good as those of the +filesystem providing the backing services. Note that CacheFiles does not +attempt to journal anything since the journalling interfaces of the various +filesystems are very specific in nature. + +CacheFiles creates a misc character device - "/dev/cachefiles" - that is used +to communication with the daemon. Only one thing may have this open at once, +and whilst it is open, a cache is at least partially in existence. The daemon +opens this and sends commands down it to control the cache. + +CacheFiles is currently limited to a single cache. + +CacheFiles attempts to maintain at least a certain percentage of free space on +the filesystem, shrinking the cache by culling the objects it contains to make +space if necessary - see the "Cache Culling" section. This means it can be +placed on the same medium as a live set of data, and will expand to make use of +spare space and automatically contract when the set of data requires more +space. + + +============ +REQUIREMENTS +============ + +The use of CacheFiles and its daemon requires the following features to be +available in the system and in the cache filesystem: + + - dnotify. + + - extended attributes (xattrs). + + - openat() and friends. + + - bmap() support on files in the filesystem (FIBMAP ioctl). + + - The use of bmap() to detect a partial page at the end of the file. + +It is strongly recommended that the "dir_index" option is enabled on Ext3 +filesystems being used as a cache. + + +============= +CONFIGURATION +============= + +The cache is configured by a script in /etc/cachefilesd.conf. These commands +set up cache ready for use. The following script commands are available: + + (*) brun % + (*) bcull % + (*) bstop % + (*) frun % + (*) fcull % + (*) fstop % + + Configure the culling limits. Optional. See the section on culling + The defaults are 7% (run), 5% (cull) and 1% (stop) respectively. + + The commands beginning with a 'b' are file space (block) limits, those + beginning with an 'f' are file count limits. + + (*) dir + + Specify the directory containing the root of the cache. Mandatory. + + (*) tag + + Specify a tag to FS-Cache to use in distinguishing multiple caches. + Optional. The default is "CacheFiles". + + (*) debug + + Specify a numeric bitmask to control debugging in the kernel module. + Optional. The default is zero (all off). The following values can be + OR'd into the mask to collect various information: + + 1 Turn on trace of function entry (_enter() macros) + 2 Turn on trace of function exit (_leave() macros) + 4 Turn on trace of internal debug points (_debug()) + + This mask can also be set through sysfs, eg: + + echo 5 >/sys/modules/cachefiles/parameters/debug + + +================== +STARTING THE CACHE +================== + +The cache is started by running the daemon. The daemon opens the cache device, +configures the cache and tells it to begin caching. At that point the cache +binds to fscache and the cache becomes live. + +The daemon is run as follows: + + /sbin/cachefilesd [-d]* [-s] [-n] [-f ] + +The flags are: + + (*) -d + + Increase the debugging level. This can be specified multiple times and + is cumulative with itself. + + (*) -s + + Send messages to stderr instead of syslog. + + (*) -n + + Don't daemonise and go into background. + + (*) -f + + Use an alternative configuration file rather than the default one. + + +=============== +THINGS TO AVOID +=============== + +Do not mount other things within the cache as this will cause problems. The +kernel module contains its own very cut-down path walking facility that ignores +mountpoints, but the daemon can't avoid them. + +Do not create, rename or unlink files and directories in the cache whilst the +cache is active, as this may cause the state to become uncertain. + +Renaming files in the cache might make objects appear to be other objects (the +filename is part of the lookup key). + +Do not change or remove the extended attributes attached to cache files by the +cache as this will cause the cache state management to get confused. + +Do not create files or directories in the cache, lest the cache get confused or +serve incorrect data. + +Do not chmod files in the cache. The module creates things with minimal +permissions to prevent random users being able to access them directly. + + +============= +CACHE CULLING +============= + +The cache may need culling occasionally to make space. This involves +discarding objects from the cache that have been used less recently than +anything else. Culling is based on the access time of data objects. Empty +directories are culled if not in use. + +Cache culling is done on the basis of the percentage of blocks and the +percentage of files available in the underlying filesystem. There are six +"limits": + + (*) brun + (*) frun + + If the amount of free space and the number of available files in the cache + rises above both these limits, then culling is turned off. + + (*) bcull + (*) fcull + + If the amount of available space or the number of available files in the + cache falls below either of these limits, then culling is started. + + (*) bstop + (*) fstop + + If the amount of available space or the number of available files in the + cache falls below either of these limits, then no further allocation of + disk space or files is permitted until culling has raised things above + these limits again. + +These must be configured thusly: + + 0 <= bstop < bcull < brun < 100 + 0 <= fstop < fcull < frun < 100 + +Note that these are percentages of available space and available files, and do +_not_ appear as 100 minus the percentage displayed by the "df" program. + +The userspace daemon scans the cache to build up a table of cullable objects. +These are then culled in least recently used order. A new scan of the cache is +started as soon as space is made in the table. Objects will be skipped if +their atimes have changed or if the kernel module says it is still using them. + + +=============== +CACHE STRUCTURE +=============== + +The CacheFiles module will create two directories in the directory it was +given: + + (*) cache/ + + (*) graveyard/ + +The active cache objects all reside in the first directory. The CacheFiles +kernel module moves any retired or culled objects that it can't simply unlink +to the graveyard from which the daemon will actually delete them. + +The daemon uses dnotify to monitor the graveyard directory, and will delete +anything that appears therein. + + +The module represents index objects as directories with the filename "I..." or +"J...". Note that the "cache/" directory is itself a special index. + +Data objects are represented as files if they have no children, or directories +if they do. Their filenames all begin "D..." or "E...". If represented as a +directory, data objects will have a file in the directory called "data" that +actually holds the data. + +Special objects are similar to data objects, except their filenames begin +"S..." or "T...". + + +If an object has children, then it will be represented as a directory. +Immediately in the representative directory are a collection of directories +named for hash values of the child object keys with an '@' prepended. Into +this directory, if possible, will be placed the representations of the child +objects: + + INDEX INDEX INDEX DATA FILES + ========= ========== ================================= ================ + cache/@4a/I03nfs/@30/Ji000000000000000--fHg8hi8400 + cache/@4a/I03nfs/@30/Ji000000000000000--fHg8hi8400/@75/Es0g000w...DB1ry + cache/@4a/I03nfs/@30/Ji000000000000000--fHg8hi8400/@75/Es0g000w...N22ry + cache/@4a/I03nfs/@30/Ji000000000000000--fHg8hi8400/@75/Es0g000w...FP1ry + + +If the key is so long that it exceeds NAME_MAX with the decorations added on to +it, then it will be cut into pieces, the first few of which will be used to +make a nest of directories, and the last one of which will be the objects +inside the last directory. The names of the intermediate directories will have +'+' prepended: + + J1223/@23/+xy...z/+kl...m/Epqr + + +Note that keys are raw data, and not only may they exceed NAME_MAX in size, +they may also contain things like '/' and NUL characters, and so they may not +be suitable for turning directly into a filename. + +To handle this, CacheFiles will use a suitably printable filename directly and +"base-64" encode ones that aren't directly suitable. The two versions of +object filenames indicate the encoding: + + OBJECT TYPE PRINTABLE ENCODED + =============== =============== =============== + Index "I..." "J..." + Data "D..." "E..." + Special "S..." "T..." + +Intermediate directories are always "@" or "+" as appropriate. + + +Each object in the cache has an extended attribute label that holds the object +type ID (required to distinguish special objects) and the auxiliary data from +the netfs. The latter is used to detect stale objects in the cache and update +or retire them. + + +Note that CacheFiles will erase from the cache any file it doesn't recognise or +any file of an incorrect type (such as a FIFO file or a device file). + + +========================== +SECURITY MODEL AND SELINUX +========================== + +CacheFiles is implemented to deal properly with the LSM security features of +the Linux kernel and the SELinux facility. + +One of the problems that CacheFiles faces is that it is generally acting on +behalf of a process, and running in that process's context, and that includes a +security context that is not appropriate for accessing the cache - either +because the files in the cache are inaccessible to that process, or because if +the process creates a file in the cache, that file may be inaccessible to other +processes. + +The way CacheFiles works is to temporarily change the security context (fsuid, +fsgid and actor security label) that the process acts as - without changing the +security context of the process when it the target of an operation performed by +some other process (so signalling and suchlike still work correctly). + + +When the CacheFiles module is asked to bind to its cache, it: + + (1) Finds the security label attached to the root cache directory and uses + that as the security label with which it will create files. By default, + this is: + + cachefiles_var_t + + (2) Finds the security label of the process which issued the bind request + (presumed to be the cachefilesd daemon), which by default will be: + + cachefilesd_t + + and asks LSM to supply a security ID as which it should act given the + daemon's label. By default, this will be: + + cachefiles_kernel_t + + SELinux transitions the daemon's security ID to the module's security ID + based on a rule of this form in the policy. + + type_transition kernel_t : process ; + + For instance: + + type_transition cachefilesd_t kernel_t : process cachefiles_kernel_t; + + +The module's security ID gives it permission to create, move and remove files +and directories in the cache, to find and access directories and files in the +cache, to set and access extended attributes on cache objects, and to read and +write files in the cache. + +The daemon's security ID gives it only a very restricted set of permissions: it +may scan directories, stat files and erase files and directories. It may +not read or write files in the cache, and so it is precluded from accessing the +data cached therein; nor is it permitted to create new files in the cache. + + +There are policy source files available in: + + http://people.redhat.com/~dhowells/fscache/cachefilesd-0.8.tar.bz2 + +and later versions. In that tarball, see the files: + + cachefilesd.te + cachefilesd.fc + cachefilesd.if + +They are built and installed directly by the RPM. + +If a non-RPM based system is being used, then copy the above files to their own +directory and run: + + make -f /usr/share/selinux/devel/Makefile + semodule -i cachefilesd.pp + +You will need checkpolicy and selinux-policy-devel installed prior to the +build. + + +By default, the cache is located in /var/fscache, but if it is desirable that +it should be elsewhere, than either the above policy files must be altered, or +an auxiliary policy must be installed to label the alternate location of the +cache. + +For instructions on how to add an auxiliary policy to enable the cache to be +located elsewhere when SELinux is in enforcing mode, please see: + + /usr/share/doc/cachefilesd-*/move-cache.txt + +When the cachefilesd rpm is installed; alternatively, the document can be found +in the sources. + + +================== +A NOTE ON SECURITY +================== + +CacheFiles makes use of the split security in the task_struct. It allocates +its own task_security structure, and redirects current->act_as to point to it +when it acts on behalf of another process, in that process's context. + +The reason it does this is that it calls vfs_mkdir() and suchlike rather than +bypassing security and calling inode ops directly. Therefore the VFS and LSM +may deny the CacheFiles access to the cache data because under some +circumstances the caching code is running in the security context of whatever +process issued the original syscall on the netfs. + +Furthermore, should CacheFiles create a file or directory, the security +parameters with that object is created (UID, GID, security label) would be +derived from that process that issued the system call, thus potentially +preventing other processes from accessing the cache - including CacheFiles's +cache management daemon (cachefilesd). + +What is required is to temporarily override the security of the process that +issued the system call. We can't, however, just do an in-place change of the +security data as that affects the process as an object, not just as a subject. +This means it may lose signals or ptrace events for example, and affects what +the process looks like in /proc. + +So CacheFiles makes use of a logical split in the security between the +objective security (task->sec) and the subjective security (task->act_as). The +objective security holds the intrinsic security properties of a process and is +never overridden. This is what appears in /proc, and is what is used when a +process is the target of an operation by some other process (SIGKILL for +example). + +The subjective security holds the active security properties of a process, and +may be overridden. This is not seen externally, and is used whan a process +acts upon another object, for example SIGKILLing another process or opening a +file. + +LSM hooks exist that allow SELinux (or Smack or whatever) to reject a request +for CacheFiles to run in a context of a specific security label, or to create +files and directories with another security label. + + +======================= +STATISTICAL INFORMATION +======================= + +If FS-Cache is compiled with the following option enabled: + + CONFIG_CACHEFILES_HISTOGRAM=y + +then it will gather certain statistics and display them through a proc file. + + (*) /proc/fs/cachefiles/histogram + + cat /proc/fs/cachefiles/histogram + JIFS SECS LOOKUPS MKDIRS CREATES + ===== ===== ========= ========= ========= + + This shows the breakdown of the number of times each amount of time + between 0 jiffies and HZ-1 jiffies a variety of tasks took to run. The + columns are as follows: + + COLUMN TIME MEASUREMENT + ======= ======================================================= + LOOKUPS Length of time to perform a lookup on the backing fs + MKDIRS Length of time to perform a mkdir on the backing fs + CREATES Length of time to perform a create on the backing fs + + Each row shows the number of events that took a particular range of times. + Each step is 1 jiffy in size. The JIFS column indicates the particular + jiffy range covered, and the SECS field the equivalent number of seconds. + + +========= +DEBUGGING +========= + +If CONFIG_CACHEFILES_DEBUG is enabled, the CacheFiles facility can have runtime +debugging enabled by adjusting the value in: + + /sys/module/cachefiles/parameters/debug + +This is a bitmask of debugging streams to enable: + + BIT VALUE STREAM POINT + ======= ======= =============================== ======================= + 0 1 General Function entry trace + 1 2 Function exit trace + 2 4 General + +The appropriate set of values should be OR'd together and the result written to +the control file. For example: + + echo $((1|4|8)) >/sys/module/cachefiles/parameters/debug + +will turn on all function entry debugging. -- cgit v1.2.3 From 04c860c188ebdcf396fd50751592fb5a9f51287a Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Fri, 3 Apr 2009 14:50:52 +0100 Subject: LANANA: Change of management and resync Bring the devices.txt back into some relationship with reality. Update the documentation a bit. Signed-off-by: Alan Cox Signed-off-by: Linus Torvalds --- Documentation/devices.txt | 121 ++++++++++++++++++++++------------------------ 1 file changed, 58 insertions(+), 63 deletions(-) (limited to 'Documentation') diff --git a/Documentation/devices.txt b/Documentation/devices.txt index 62254d4510c..327de162475 100644 --- a/Documentation/devices.txt +++ b/Documentation/devices.txt @@ -1,7 +1,7 @@ LINUX ALLOCATED DEVICES (2.6+ version) - Maintained by Torben Mathiasen + Maintained by Alan Cox Last revised: 29 November 2006 @@ -67,6 +67,11 @@ up to date. Due to the number of registrations I have to maintain it in "batch mode", so there is likely additional registrations that haven't been listed yet. +Fourth, remember that Linux now has extensive support for dynamic allocation +of device numbering and can use sysfs and udev to handle the naming needs. +There are still some exceptions in the serial and boot device area. Before +asking for a device number make sure you actually need one. + Finally, sometimes I have to play "namespace police." Please don't be offended. I often get submissions for /dev names that would be bound to cause conflicts down the road. I am trying to avoid getting in a @@ -101,7 +106,7 @@ Your cooperation is appreciated. 0 = /dev/ram0 First RAM disk 1 = /dev/ram1 Second RAM disk ... - 250 = /dev/initrd Initial RAM disk {2.6} + 250 = /dev/initrd Initial RAM disk Older kernels had /dev/ramdisk (1, 1) here. /dev/initrd refers to a RAM disk which was preloaded @@ -340,7 +345,7 @@ Your cooperation is appreciated. 14 = /dev/touchscreen/ucb1x00 UCB 1x00 touchscreen 15 = /dev/touchscreen/mk712 MK712 touchscreen 128 = /dev/beep Fancy beep device - 129 = /dev/modreq Kernel module load request {2.6} + 129 = 130 = /dev/watchdog Watchdog timer port 131 = /dev/temperature Machine internal temperature 132 = /dev/hwtrap Hardware fault trap @@ -350,10 +355,10 @@ Your cooperation is appreciated. 139 = /dev/openprom SPARC OpenBoot PROM 140 = /dev/relay8 Berkshire Products Octal relay card 141 = /dev/relay16 Berkshire Products ISO-16 relay card - 142 = /dev/msr x86 model-specific registers {2.6} + 142 = 143 = /dev/pciconf PCI configuration space 144 = /dev/nvram Non-volatile configuration RAM - 145 = /dev/hfmodem Soundcard shortwave modem control {2.6} + 145 = /dev/hfmodem Soundcard shortwave modem control 146 = /dev/graphics Linux/SGI graphics device 147 = /dev/opengl Linux/SGI OpenGL pipe 148 = /dev/gfx Linux/SGI graphics effects device @@ -435,6 +440,9 @@ Your cooperation is appreciated. 228 = /dev/hpet HPET driver 229 = /dev/fuse Fuse (virtual filesystem in user-space) 230 = /dev/midishare MidiShare driver + 231 = /dev/snapshot System memory snapshot device + 232 = /dev/kvm Kernel-based virtual machine (hardware virtualization extensions) + 233 = /dev/kmview View-OS A process with a view 240-254 Reserved for local use 255 Reserved for MISC_DYNAMIC_MINOR @@ -466,10 +474,7 @@ Your cooperation is appreciated. The device names specified are proposed -- if there are "standard" names for these devices, please let me know. - 12 block MSCDEX CD-ROM callback support {2.6} - 0 = /dev/dos_cd0 First MSCDEX CD-ROM - 1 = /dev/dos_cd1 Second MSCDEX CD-ROM - ... + 12 block 13 char Input core 0 = /dev/input/js0 First joystick @@ -498,7 +503,7 @@ Your cooperation is appreciated. 2 = /dev/midi00 First MIDI port 3 = /dev/dsp Digital audio 4 = /dev/audio Sun-compatible digital audio - 6 = /dev/sndstat Sound card status information {2.6} + 6 = 7 = /dev/audioctl SPARC audio control device 8 = /dev/sequencer2 Sequencer -- alternate device 16 = /dev/mixer1 Second soundcard mixer control @@ -510,14 +515,7 @@ Your cooperation is appreciated. 34 = /dev/midi02 Third MIDI port 50 = /dev/midi03 Fourth MIDI port - 14 block BIOS harddrive callback support {2.6} - 0 = /dev/dos_hda First BIOS harddrive whole disk - 64 = /dev/dos_hdb Second BIOS harddrive whole disk - 128 = /dev/dos_hdc Third BIOS harddrive whole disk - 192 = /dev/dos_hdd Fourth BIOS harddrive whole disk - - Partitions are handled in the same way as IDE disks - (see major number 3). + 14 block 15 char Joystick 0 = /dev/js0 First analog joystick @@ -535,14 +533,14 @@ Your cooperation is appreciated. 16 block GoldStar CD-ROM 0 = /dev/gscd GoldStar CD-ROM - 17 char Chase serial card + 17 char OBSOLETE (was Chase serial card) 0 = /dev/ttyH0 First Chase port 1 = /dev/ttyH1 Second Chase port ... 17 block Optics Storage CD-ROM 0 = /dev/optcd Optics Storage CD-ROM - 18 char Chase serial card - alternate devices + 18 char OBSOLETE (was Chase serial card - alternate devices) 0 = /dev/cuh0 Callout device for ttyH0 1 = /dev/cuh1 Callout device for ttyH1 ... @@ -644,8 +642,7 @@ Your cooperation is appreciated. 2 = /dev/sbpcd2 Panasonic CD-ROM controller 0 unit 2 3 = /dev/sbpcd3 Panasonic CD-ROM controller 0 unit 3 - 26 char Quanta WinVision frame grabber {2.6} - 0 = /dev/wvisfgrab Quanta WinVision frame grabber + 26 char 26 block Second Matsushita (Panasonic/SoundBlaster) CD-ROM 0 = /dev/sbpcd4 Panasonic CD-ROM controller 1 unit 0 @@ -872,7 +869,7 @@ Your cooperation is appreciated. and "user level packet I/O." This board is also accessible as a standard networking "eth" device. - 38 block Reserved for Linux/AP+ + 38 block OBSOLETE (was Linux/AP+) 39 char ML-16P experimental I/O board 0 = /dev/ml16pa-a0 First card, first analog channel @@ -892,29 +889,16 @@ Your cooperation is appreciated. 50 = /dev/ml16pb-c1 Second card, second counter/timer 51 = /dev/ml16pb-c2 Second card, third counter/timer ... - 39 block Reserved for Linux/AP+ + 39 block - 40 char Matrox Meteor frame grabber {2.6} - 0 = /dev/mmetfgrab Matrox Meteor frame grabber + 40 char - 40 block Syquest EZ135 parallel port removable drive - 0 = /dev/eza Parallel EZ135 drive, whole disk - - This device is obsolete and will be removed in a - future version of Linux. It has been replaced with - the parallel port IDE disk driver at major number 45. - Partitions are handled in the same way as IDE disks - (see major number 3). + 40 block 41 char Yet Another Micro Monitor 0 = /dev/yamm Yet Another Micro Monitor - 41 block MicroSolutions BackPack parallel port CD-ROM - 0 = /dev/bpcd BackPack CD-ROM - - This device is obsolete and will be removed in a - future version of Linux. It has been replaced with - the parallel port ATAPI CD-ROM driver at major number 46. + 41 block 42 char Demo/sample use @@ -1681,13 +1665,7 @@ Your cooperation is appreciated. disks (see major number 3) except that the limit on partitions is 15. - 93 char IBM Smart Capture Card frame grabber {2.6} - 0 = /dev/iscc0 First Smart Capture Card - 1 = /dev/iscc1 Second Smart Capture Card - ... - 128 = /dev/isccctl0 First Smart Capture Card control - 129 = /dev/isccctl1 Second Smart Capture Card control - ... + 93 char 93 block NAND Flash Translation Layer filesystem 0 = /dev/nftla First NFTL layer @@ -1695,10 +1673,7 @@ Your cooperation is appreciated. ... 240 = /dev/nftlp 16th NTFL layer - 94 char miroVIDEO DC10/30 capture/playback device {2.6} - 0 = /dev/dcxx0 First capture card - 1 = /dev/dcxx1 Second capture card - ... + 94 char 94 block IBM S/390 DASD block storage 0 = /dev/dasda First DASD device, major @@ -1791,11 +1766,7 @@ Your cooperation is appreciated. ... 15 = /dev/amiraid/ar?p15 15th partition -102 char Philips SAA5249 Teletext signal decoder {2.6} - 0 = /dev/tlk0 First Teletext decoder - 1 = /dev/tlk1 Second Teletext decoder - 2 = /dev/tlk2 Third Teletext decoder - 3 = /dev/tlk3 Fourth Teletext decoder +102 char 102 block Compressed block device 0 = /dev/cbd/a First compressed block device, whole device @@ -1916,10 +1887,7 @@ Your cooperation is appreciated. DAC960 (see major number 48) except that the limit on partitions is 15. -111 char Philips SAA7146-based audio/video card {2.6} - 0 = /dev/av0 First A/V card - 1 = /dev/av1 Second A/V card - ... +111 char 111 block Compaq Next Generation Drive Array, eighth controller 0 = /dev/cciss/c7d0 First logical drive, whole disk @@ -2079,8 +2047,8 @@ Your cooperation is appreciated. ... 119 char VMware virtual network control - 0 = /dev/vmnet0 1st virtual network - 1 = /dev/vmnet1 2nd virtual network + 0 = /dev/vnet0 1st virtual network + 1 = /dev/vnet1 2nd virtual network ... 120-127 char LOCAL/EXPERIMENTAL USE @@ -2450,7 +2418,7 @@ Your cooperation is appreciated. 2 = /dev/raw/raw2 Second raw I/O device ... -163 char UNASSIGNED (was Radio Tech BIM-XXX-RS232 radio modem - see 51) +163 char 164 char Chase Research AT/PCI-Fast serial card 0 = /dev/ttyCH0 AT/PCI-Fast board 0, port 0 @@ -2542,6 +2510,12 @@ Your cooperation is appreciated. 1 = /dev/clanvi1 Second cLAN adapter ... +179 block MMC block devices + 0 = /dev/mmcblk0 First SD/MMC card + 1 = /dev/mmcblk0p1 First partition on first MMC card + 8 = /dev/mmcblk1 Second SD/MMC card + ... + 179 char CCube DVXChip-based PCI products 0 = /dev/dvxirq0 First DVX device 1 = /dev/dvxirq1 Second DVX device @@ -2560,6 +2534,9 @@ Your cooperation is appreciated. 96 = /dev/usb/hiddev0 1st USB HID device ... 111 = /dev/usb/hiddev15 16th USB HID device + 112 = /dev/usb/auer0 1st auerswald ISDN device + ... + 127 = /dev/usb/auer15 16th auerswald ISDN device 128 = /dev/usb/brlvgr0 First Braille Voyager device ... 131 = /dev/usb/brlvgr3 Fourth Braille Voyager device @@ -2810,6 +2787,16 @@ Your cooperation is appreciated. ... 190 = /dev/ttyUL3 Xilinx uartlite - port 3 191 = /dev/xvc0 Xen virtual console - port 0 + 192 = /dev/ttyPZ0 pmac_zilog - port 0 + ... + 195 = /dev/ttyPZ3 pmac_zilog - port 3 + 196 = /dev/ttyTX0 TX39/49 serial port 0 + ... + 204 = /dev/ttyTX7 TX39/49 serial port 7 + 205 = /dev/ttySC0 SC26xx serial port 0 + 206 = /dev/ttySC1 SC26xx serial port 1 + 207 = /dev/ttySC2 SC26xx serial port 2 + 208 = /dev/ttySC3 SC26xx serial port 3 205 char Low-density serial ports (alternate device) 0 = /dev/culu0 Callout device for ttyLU0 @@ -3145,6 +3132,14 @@ Your cooperation is appreciated. 1 = /dev/blockrom1 Second ROM card's translation layer interface ... +259 block Block Extended Major + Used dynamically to hold additional partition minor + numbers and allow large numbers of partitions per device + +259 char FPGA configuration interfaces + 0 = /dev/icap0 First Xilinx internal configuration + 1 = /dev/icap1 Second Xilinx internal configuration + 260 char OSD (Object-based-device) SCSI Device 0 = /dev/osd0 First OSD Device 1 = /dev/osd1 Second OSD Device -- cgit v1.2.3