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Note that this is slightly tricky since both drivers store their
native objects in dma_buf->priv. But both also embed the base
drm_gem_object at the first position, so the implicit cast is ok.
To use the release helper we need to export it, too.
Change-Id: I37e9ffec79c90304d444ae9b6c47346f125feb49
Cc: Inki Dae <inki.dae@samsung.com>
Cc: Intel Graphics Development <intel-gfx@lists.freedesktop.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
[This patch is necessary for commit 7f663e197afa drm/prime: proper locking+refcounting for obj->dma_buf link]
Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
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task_cgroup_path_from_hierarchy() was added for the planned new users
and none of the currently planned users wants to know about multiple
hierarchies. This patch drops the multiple hierarchy part and makes
it always return the path in the first non-dummy hierarchy.
As unified hierarchy will always have id 1, this is guaranteed to
return the path for the unified hierarchy if mounted; otherwise, it
will return the path from the hierarchy which happens to occupy the
lowest hierarchy id, which will usually be the first hierarchy mounted
after boot.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Jan Kaluža <jkaluza@redhat.com>
Change-Id: Iaa199f7332f01a03f791def776b5403f6fa459b3
Origin: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=913ffdb54366f94eec65c656cae8c6e00e1ab1b0
Backported-by: Maciej Wereski <m.wereski@partner.samsung.com>
Signed-off-by: Maciej Wereski <m.wereski@partner.samsung.com>
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kdbus folks want a sane way to determine the cgroup path that a given
task belongs to on a given hierarchy, which is a reasonble thing to
expect from cgroup core.
Implement task_cgroup_path_from_hierarchy().
v2: Dropped unnecessary NULL check on the return value of
task_cgroup_from_root() as suggested by Li Zefan.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Greg Kroah-Hartman <greg@kroah.com>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Kay Sievers <kay@vrfy.org>
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Daniel Mack <daniel@zonque.org>
Change-Id: Ifd630e09163b8272627c2ef8be1866c5e9dc05f9
Origin: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=857a2beb09ab83e9a8185821ae16db7dfbe8b837
Backported-by: Maciej Wereski <m.wereski@partner.samsung.com>
Signed-off-by: Maciej Wereski <m.wereski@partner.samsung.com>
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The new header file memfd.h from commit 9183df25fe7b ("shm: add
memfd_create() syscall") should be exported.
Signed-off-by: David Drysdale <drysdale@google.com>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change-Id: Ibcd915aad320ddedcfcca0b7a098e03cc883fd88
Origin: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=b01d072065b6f36550f486fe77f05b092225ba1b
Backported-by: Maciej Wereski <m.wereski@partner.samsung.com>
Signed-off-by: Maciej Wereski <m.wereski@partner.samsung.com>
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Commit 9183df25fe7b ("shm: add memfd_create() syscall") added a new
system call (memfd_create) but didn't update the asm-generic unistd
header.
This patch adds the new system call to the asm-generic version of
unistd.h so that it can be used by architectures such as arm64.
Cc: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Change-Id: I7fff684716a86ad9f10e19755480c32ce9eeb861
Origin: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=503e6636b6f96056210062be703356f4253b6db9
Backported-by: Maciej Wereski <m.wereski@partner.samsung.com>
Signed-off-by: Maciej Wereski <m.wereski@partner.samsung.com>
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memfd_create() is similar to mmap(MAP_ANON), but returns a file-descriptor
that you can pass to mmap(). It can support sealing and avoids any
connection to user-visible mount-points. Thus, it's not subject to quotas
on mounted file-systems, but can be used like malloc()'ed memory, but with
a file-descriptor to it.
memfd_create() returns the raw shmem file, so calls like ftruncate() can
be used to modify the underlying inode. Also calls like fstat() will
return proper information and mark the file as regular file. If you want
sealing, you can specify MFD_ALLOW_SEALING. Otherwise, sealing is not
supported (like on all other regular files).
Compared to O_TMPFILE, it does not require a tmpfs mount-point and is not
subject to a filesystem size limit. It is still properly accounted to
memcg limits, though, and to the same overcommit or no-overcommit
accounting as all user memory.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Ryan Lortie <desrt@desrt.ca>
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Daniel Mack <zonque@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change-Id: I2ac7e2b47a1d68d4b83680f4527e5ed2aa9a420c
Origin: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=9183df25fe7b194563db3fec6dc3202a5855839c
Backported-by: Maciej Wereski <m.wereski@partner.samsung.com>
Signed-off-by: Maciej Wereski <m.wereski@partner.samsung.com>
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If two processes share a common memory region, they usually want some
guarantees to allow safe access. This often includes:
- one side cannot overwrite data while the other reads it
- one side cannot shrink the buffer while the other accesses it
- one side cannot grow the buffer beyond previously set boundaries
If there is a trust-relationship between both parties, there is no need
for policy enforcement. However, if there's no trust relationship (eg.,
for general-purpose IPC) sharing memory-regions is highly fragile and
often not possible without local copies. Look at the following two
use-cases:
1) A graphics client wants to share its rendering-buffer with a
graphics-server. The memory-region is allocated by the client for
read/write access and a second FD is passed to the server. While
scanning out from the memory region, the server has no guarantee that
the client doesn't shrink the buffer at any time, requiring rather
cumbersome SIGBUS handling.
2) A process wants to perform an RPC on another process. To avoid huge
bandwidth consumption, zero-copy is preferred. After a message is
assembled in-memory and a FD is passed to the remote side, both sides
want to be sure that neither modifies this shared copy, anymore. The
source may have put sensible data into the message without a separate
copy and the target may want to parse the message inline, to avoid a
local copy.
While SIGBUS handling, POSIX mandatory locking and MAP_DENYWRITE provide
ways to achieve most of this, the first one is unproportionally ugly to
use in libraries and the latter two are broken/racy or even disabled due
to denial of service attacks.
This patch introduces the concept of SEALING. If you seal a file, a
specific set of operations is blocked on that file forever. Unlike locks,
seals can only be set, never removed. Hence, once you verified a specific
set of seals is set, you're guaranteed that no-one can perform the blocked
operations on this file, anymore.
An initial set of SEALS is introduced by this patch:
- SHRINK: If SEAL_SHRINK is set, the file in question cannot be reduced
in size. This affects ftruncate() and open(O_TRUNC).
- GROW: If SEAL_GROW is set, the file in question cannot be increased
in size. This affects ftruncate(), fallocate() and write().
- WRITE: If SEAL_WRITE is set, no write operations (besides resizing)
are possible. This affects fallocate(PUNCH_HOLE), mmap() and
write().
- SEAL: If SEAL_SEAL is set, no further seals can be added to a file.
This basically prevents the F_ADD_SEAL operation on a file and
can be set to prevent others from adding further seals that you
don't want.
The described use-cases can easily use these seals to provide safe use
without any trust-relationship:
1) The graphics server can verify that a passed file-descriptor has
SEAL_SHRINK set. This allows safe scanout, while the client is
allowed to increase buffer size for window-resizing on-the-fly.
Concurrent writes are explicitly allowed.
2) For general-purpose IPC, both processes can verify that SEAL_SHRINK,
SEAL_GROW and SEAL_WRITE are set. This guarantees that neither
process can modify the data while the other side parses it.
Furthermore, it guarantees that even with writable FDs passed to the
peer, it cannot increase the size to hit memory-limits of the source
process (in case the file-storage is accounted to the source).
The new API is an extension to fcntl(), adding two new commands:
F_GET_SEALS: Return a bitset describing the seals on the file. This
can be called on any FD if the underlying file supports
sealing.
F_ADD_SEALS: Change the seals of a given file. This requires WRITE
access to the file and F_SEAL_SEAL may not already be set.
Furthermore, the underlying file must support sealing and
there may not be any existing shared mapping of that file.
Otherwise, EBADF/EPERM is returned.
The given seals are _added_ to the existing set of seals
on the file. You cannot remove seals again.
The fcntl() handler is currently specific to shmem and disabled on all
files. A file needs to explicitly support sealing for this interface to
work. A separate syscall is added in a follow-up, which creates files that
support sealing. There is no intention to support this on other
file-systems. Semantics are unclear for non-volatile files and we lack any
use-case right now. Therefore, the implementation is specific to shmem.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Ryan Lortie <desrt@desrt.ca>
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Daniel Mack <zonque@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change-Id: I58642ae2db7fef5d952b22beada3525526dd3a20
Origin: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=40e041a2c858b3caefc757e26cb85bfceae5062b
Backported-by: Maciej Wereski <m.wereski@partner.samsung.com>
Signed-off-by: Maciej Wereski <m.wereski@partner.samsung.com>
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This patch (of 6):
The i_mmap_writable field counts existing writable mappings of an
address_space. To allow drivers to prevent new writable mappings, make
this counter signed and prevent new writable mappings if it is negative.
This is modelled after i_writecount and DENYWRITE.
This will be required by the shmem-sealing infrastructure to prevent any
new writable mappings after the WRITE seal has been set. In case there
exists a writable mapping, this operation will fail with EBUSY.
Note that we rely on the fact that iff you already own a writable mapping,
you can increase the counter without using the helpers. This is the same
that we do for i_writecount.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Ryan Lortie <desrt@desrt.ca>
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Daniel Mack <zonque@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change-Id: If33fdcedbcf202ab177c4e21afc7eec261088a8b
Origin: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=4bb5f5d9395bc112d93a134d8f5b05611eddc9c0
Backported-by: Maciej Wereski <m.wereski@partner.samsung.com>
Signed-off-by: Maciej Wereski <m.wereski@partner.samsung.com>
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This is intended for use in loops which read data protected by RCU and may
have a large number of iterations. Such an example is dumping the list of
connections known to IPVS: ip_vs_conn_array() and ip_vs_conn_seq_next().
The benefits are for CONFIG_PREEMPT_RCU=y where we save CPU cycles
by moving rcu_read_lock and rcu_read_unlock out of large loops
but still allowing the current task to be preempted after every
loop iteration for the CONFIG_PREEMPT_RCU=n case.
The call to cond_resched() is not needed when CONFIG_PREEMPT_RCU=y.
Thanks to Paul E. McKenney for explaining this and for the
final version that checks the context with CONFIG_DEBUG_ATOMIC_SLEEP=y
for all possible configurations.
The function can be empty in the CONFIG_PREEMPT_RCU case,
rcu_read_lock and rcu_read_unlock are not needed in this case
because the task can be preempted on indication from scheduler.
Thanks to Peter Zijlstra for catching this and for his help
in trying a solution that changes __might_sleep.
Initial cond_resched_rcu_lock() function suggested by Eric Dumazet.
Tested-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Change-Id: I5f36f86484198f9064725d424c3d91d5fac8e1d4
Origin: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=f6f3c437d09e2f62533034e67bfb4385191e992c
Backported-by: Maciej Wereski <m.wereski@partner.samsung.com>
Signed-off-by: Maciej Wereski <m.wereski@partner.samsung.com>
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For the casual device driver writer, it is hard to remember when to use
init_completion (to init a completion structure) or INIT_COMPLETION (to
*reinit* a completion structure). Furthermore, while all other
completion functions exepct a pointer as a parameter, INIT_COMPLETION
does not. To make it easier to remember which function to use and to
make code more readable, introduce a new inline function with the proper
name and consistent argument type. Update the kernel-doc for
init_completion while we are here.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org> (personally at LCE13)
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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This patch adds notifying v4l2 subdevs upon capture
frame end event.
Signed-off-by: Beata Michalska <b.michalska@samsung.com>
Change-Id: Id3e81b4692a6f2cfc91ffde7050a3ae6db719971
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Change-Id: Ia7d3608d3ec033453147c1bb500aca144ee42902
Signed-off-by: Chanho Park <chanho61.park@samsung.com>
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The DMA Buffer synchronization API provides buffer synchronization
mechanism based on DMA buffer sharing machanism[1], dmafence and
reservation frameworks[2];
i.e., buffer access control to CPU and DMA, and easy-to-use interfaces
for device drivers and user application. And this API can be used
for all dma devices using system memory as dma buffer, especially
for most ARM based SoCs.
For more details, please refer to Documentation/dma-buf-syc.txt
[1] http://lwn.net/Articles/470339/
[2] https://lkml.org/lkml/2014/2/24/824
Change-Id: I3b2084a3c331fc06992fa8d2a4c71378e88b10b5
Signed-off-by: Inki Dae <inki.dae@samsung.com>
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The VMA offset manager uses a device-global address-space. Hence, any
user can currently map any offset-node they want. They only need to guess
the right offset. If we wanted per open-file offset spaces, we'd either
need VM_NONLINEAR mappings or multiple "struct address_space" trees. As
both doesn't really scale, we implement access management in the VMA
manager itself.
We use an rb-tree to store open-files for each VMA node. On each mmap
call, GEM, TTM or the drivers must check whether the current user is
allowed to map this file.
We add a separate lock for each node as there is no generic lock available
for the caller to protect the node easily.
As we currently don't know whether an object may be used for mmap(), we
have to do access management for all objects. If it turns out to slow down
handle creation/deletion significantly, we can optimize it in several
ways:
- Most times only a single filp is added per bo so we could use a static
"struct file *main_filp" which is checked/added/removed first before we
fall back to the rbtree+drm_vma_offset_file.
This could be even done lockless with rcu.
- Let user-space pass a hint whether mmap() should be supported on the
bo and avoid access-management if not.
- .. there are probably more ideas once we have benchmarks ..
v2: add drm_vma_node_verify_access() helper
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
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Add a "best_match" flag similar to the drm_mm_search_*() helpers so we
can convert TTM to use them in follow up patches. We can also inline the
non-generic helpers and move them into the header to allow compile-time
optimizations.
To make calls to drm_mm_{search,insert}_node() more readable, this
converts the boolean argument to a flagset. There are pending patches that
add additional flags for top-down allocators and more.
v2:
- use flag parameter instead of boolean "best_match"
- convert *_search_free() helpers to also use flags argument
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Conflicts:
drivers/gpu/drm/i915/i915_gem.c
Change-Id: I77640db74616de3c9ae874531f71bbd81b89d5fa
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Instead of unmapping the nodes in TTM and GEM users manually, we provide
a generic wrapper which does the correct thing for all vma-nodes.
v2: remove bdev->dev_mapping test in ttm_bo_unmap_virtual_unlocked() as
ttm_mem_io_free_vm() does nothing in that case (io_reserved_vm is 0).
v4: Fix docbook comments
v5: use drm_vma_node_size()
Cc: Dave Airlie <airlied@redhat.com>
Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@gmail.com>
Conflicts:
drivers/gpu/drm/ttm/ttm_bo.c
Change-Id: I4be1eeef8e5b4e81b5966449e2bf3691d8270aae
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If we want to map GPU memory into user-space, we need to linearize the
addresses to not confuse mm-core. Currently, GEM and TTM both implement
their own offset-managers to assign a pgoff to each object for user-space
CPU access. GEM uses a hash-table, TTM uses an rbtree.
This patch provides a unified implementation that can be used to replace
both. TTM allows partial mmaps with a given offset, so we cannot use
hashtables as the start address may not be known at mmap time. Hence, we
use the rbtree-implementation of TTM.
We could easily update drm_mm to use an rbtree instead of a linked list
for it's object list and thus drop the rbtree from the vma-manager.
However, this would slow down drm_mm object allocation for all other
use-cases (rbtree insertion) and add another 4-8 bytes to each mm node.
Hence, use the separate tree but allow for later migration.
This is a rewrite of the 2012-proposal by David Airlie <airlied@linux.ie>
v2:
- fix Docbook integration
- drop drm_mm_node_linked() and use drm_mm_node_allocated()
- remove unjustified likely/unlikely usage (but keep for rbtree paths)
- remove BUG_ON() as drm_mm already does that
- clarify page-based vs. byte-based addresses
- use drm_vma_node_reset() for initialization, too
v4:
- allow external locking via drm_vma_offset_un/lock_lookup()
- add locked lookup helper drm_vma_offset_lookup_locked()
v5:
- fix drm_vma_offset_lookup() to correctly validate range-mismatches
(fix (offset > start + pages))
- fix drm_vma_offset_exact_lookup() to actually do what it says
- remove redundant vm_pages member (add drm_vma_node_size() helper)
- remove unneeded goto
- fix documentation
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@gmail.com>
Conflicts:
Documentation/DocBook/drm.tmpl
drivers/gpu/drm/Makefile
Change-Id: If3427d06b0f9b24c65268912bb75c1b90fe9ad26
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The gem flink name holds a reference onto the object itself, and this
self-reference would prevent an flink'ed object from every being
freed. To break that loop we remove the flink name when the last
userspace handle disappears, i.e. when obj->handle_count reaches 0.
Now in gem_open we drop the dev->object_name_lock between the flink
name lookup and actually adding the handle. This means a concurrent
gem_close of the last handle could result in the flink name getting
reaped right inbetween, i.e.
Thread 1 Thread 2
gem_open gem_close
flink -> obj lookup
handle_count drops to 0
remove flink name
create_handle
handle_count++
If someone now flinks this object again, we'll get a new flink name.
We can close this race by removing the lock dropping and making the
entire lookup+handle_create sequence atomic. Unfortunately to still be
able to share the handle_create logic this requires a
handle_create_tail function which drops the lock - we can't hold the
object_name_lock while calling into a driver's ->gem_open callback.
Note that for flink fixing this race isn't really important, since
racing gem_open against gem_close is clearly a userspace bug. And no
matter how the race ends, we won't leak any references.
But with dma-buf where the userspace dma-buf fd itself is refcounted
this is a valid sequence and hence we should fix it. Therefore this
patch here is just a warm-up exercise (and for consistency between
flink buffer sharing and dma-buf buffer sharing with self-imports).
Also note that this extension of the critical section in gem_open
protected by dev->object_name_lock only works because it's now a
mutex: A spinlock would conflict with the potential memory allocation
in idr_preload().
This is exercises by igt/gem_flink_race/flink_name.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
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I want to wrap the creation of a dma-buf from a gem object in it,
so that the obj->export_dma_buf cache can be atomically filled in.
Instead of creating a new mutex just for that variable I've figured
I can reuse the existing dev->object_name_lock, especially since
the new semantics will exactly mirror the flink obj->name already
protected by that lock.
v2: idr_preload/idr_preload_end is now an atomic section, so need to
move the mutex locking outside.
[airlied: fix up conflict with patch to make debugfs use lock]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Conflicts:
drivers/gpu/drm/drm_info.c
Change-Id: Ic4ca630b9c6092c942208ee9a04409d4f6561fc0
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No one outside of drm should use this, the official interfaces are
drm_gem_handle_create and drm_gem_handle_delete. The handle refcounting
is purely an implementation detail of gem.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
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This is the 2nd attempt, I've always been a bit dissatisified with the
tricky nature of the first one:
http://lists.freedesktop.org/archives/dri-devel/2012-July/025451.html
The issue is that the flink ioctl can race with calling gem_close on
the last gem handle. In that case we'll end up with a zero handle
count, but an flink name (and it's corresponding reference). Which
results in a neat space leak.
In my first attempt I've solved this by rechecking the handle count.
But fundamentally the issue is that ->handle_count isn't your usual
refcount - it can be resurrected from 0 among other things.
For those special beasts atomic_t often suggest way more ordering that
it actually guarantees. To prevent being tricked by those hairy
semantics take the easy way out and simply protect the handle with the
existing dev->object_name_lock.
With that change implemented it's dead easy to fix the flink vs. gem
close reace: When we try to create the name we simply have to check
whether there's still officially a gem handle around and if not refuse
to create the flink name. Since the handle count decrement and flink
name destruction is now also protected by that lock the reace is gone
and we can't ever leak the flink reference again.
Outside of the drm core only the exynos driver looks at the handle
count, and tbh I have no idea why (it's just for debug dmesg output
luckily).
I've considered inlining the drm_gem_object_handle_free, but I plan to
add more name-like things (like the exported dma_buf) to this scheme,
so it's clearer to leave the handle freeing in its own function.
This is exercised by the new gem_flink_race i-g-t testcase, which on
my snb leaks gem objects at a rate of roughly 1k objects/s.
v2: Fix up the error path handling in handle_create and make it more
robust by simply calling object_handle_unreference.
v3: Fix up the handle_unreference logic bug - atomic_dec_and_test
retursn 1 for 0. Oops.
v4: Squash in inlining of drm_gem_object_handle_reference as suggested
by Dave Airlie and add a note that we now have a testcase.
Cc: Dave Airlie <airlied@gmail.com>
Cc: Inki Dae <inki.dae@samsung.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
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|
We have three callers of this function now and it's neither
performance critical nor really small. So an inline function feels
like overkill and unecessarily separates the different parts of the
code.
Since all callers of drm_gem_object_handle_free are now in drm_gem.c
we can make that static (and remove the unused EXPORT_SYMBOL). To
avoid a forward declaration move it (and drm_gem_object_free_bug) up a
bit.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
|
|
It's unused, everyone is using the _unlocked variant only.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Dave Airlie <airlied@gmail.com>
|
|
Basically just extracting some code duplicated in gma500, omapdrm, udl,
and upcoming msm driver.
Signed-off-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
|
|
Variant of drm_gem_create_mmap_offset() which doesn't make the
assumption that virtual size and physical size (obj->size) are the same.
This is needed in omapdrm to deal with tiled buffers. And lets us get
rid of a duplicated and slightly modified version of
drm_gem_create_mmap_offset() in omapdrm.
Signed-off-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
|
|
All the gem based kms drivers really want the same function to
destroy a dumb framebuffer backing storage object.
So give it to them and roll it out in all drivers.
This still leaves the option open for kms drivers which don't use GEM
for backing storage, but it does decently simplify matters for gem
drivers.
Acked-by: Inki Dae <inki.dae@samsung.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Intel Graphics Development <intel-gfx@lists.freedesktop.org>
Cc: Ben Skeggs <skeggsb@gmail.com>
Reviwed-by: Rob Clark <robdclark@gmail.com>
Cc: Alex Deucher <alexdeucher@gmail.com>
Acked-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Conflicts:
drivers/gpu/drm/rcar-du/rcar_du_drv.c
Change-Id: I991aad3f0745732f203a85ff8b5f43e328c045a6
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|
Use the new vma manager instead of the old hashtable. Also convert all
drivers to use the new convenience helpers. This drops all the
(map_list.hash.key << PAGE_SHIFT) non-sense.
Locking and access-management is exactly the same as before with an
additional lock inside of the vma-manager, which strictly wouldn't be
needed for gem.
v2:
- rebase on drm-next
- init nodes via drm_vma_node_reset() in drm_gem.c
v3:
- fix tegra
v4:
- remove duplicate if (drm_vma_node_has_offset()) checks
- inline now trivial drm_vma_node_offset_addr() calls
v5:
- skip node-reset on gem-init due to kzalloc()
- do not allow mapping gem-objects with offsets (backwards compat)
- remove unneccessary casts
Cc: Inki Dae <inki.dae@samsung.com>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@gmail.com>
|
|
drm_gem_object_init() and drm_gem_private_object_init() do exactly the
same (except for shmem alloc) so make the first use the latter to reduce
code duplication.
Also drop the return code from drm_gem_private_object_init(). It seems
unlikely that we will extend it any time soon so no reason to keep it
around. This simplifies code paths in drivers, too.
Last but not least, fix gma500 to call drm_gem_object_release() before
freeing objects that were allocated via drm_gem_private_object_init().
That isn't actually necessary for now, but might be in the future.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Acked-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Dave Airlie <airlied@gmail.com>
|
|
There is no reason to return "int" as this function never fails.
Furthermore, several drivers (ast, sis) already depend on this.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
|
|
The drm_gem_mmap() function first finds the GEM object to be mapped
based on the fake mmap offset and then maps the object. Split the object
mapping code into a standalone drm_gem_mmap_obj() function that can be
used to implement dma-buf mmap() operations.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
|
|
with the reworking semantics and locking of the obj->dma_buf pointer
this pointer is always set as long as there's still a gem handle
around and a dma_buf associated with this gem object.
Also, the per file-priv lookup-cache for dma-buf importing is also
unified between foreign and native objects.
Hence we don't need to special case the clean any more and can simply
drop the clause which only runs for foreing objects, i.e. with
obj->import_attach set.
Note that with this change (actually with the previous one to always
set up obj->dma_buf even for foreign objects) it is no longer required
to set obj->import_attach when importing a foreing object. So update
comments accordingly, too.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
|
|
Currently seqlocks and seqcounts don't support lockdep.
After running across a seqcount related deadlock in the timekeeping
code, I used a less-refined and more focused variant of this patch
to narrow down the cause of the issue.
This is a first-pass attempt to properly enable lockdep functionality
on seqlocks and seqcounts.
Since seqcounts are used in the vdso gettimeofday code, I've provided
non-lockdep accessors for those needs.
I've also handled one case where there were nested seqlock writers
and there may be more edge cases.
Comments and feedback would be appreciated!
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/1381186321-4906-3-git-send-email-john.stultz@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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|
The sequence lock (seqlock) was originally designed for the cases where
the readers do not need to block the writers by making the readers retry
the read operation when the data change.
Since then, the use cases have been expanded to include situations where
a thread does not need to change the data (effectively a reader) at all
but have to take the writer lock because it can't tolerate changes to
the protected structure. Some examples are the d_path() function and
the getcwd() syscall in fs/dcache.c where the functions take the writer
lock on rename_lock even though they don't need to change anything in
the protected data structure at all. This is inefficient as a reader is
now blocking other sequence number reading readers from moving forward
by pretending to be a writer.
This patch tries to eliminate this inefficiency by introducing a new
type of locking reader to the seqlock locking mechanism. This new
locking reader will try to take an exclusive lock preventing other
writers and locking readers from going forward. However, it won't
affect the progress of the other sequence number reading readers as the
sequence number won't be changed.
Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
In lockdep.h, the spinlock/mutex/rwsem/rwlock/lock_map acquire macros have
different definitions based on the value of CONFIG_PROVE_LOCKING. We have
separate ifdefs for each of these definitions, which seems redundant.
Introduce lock_acquire_{exclusive,shared,shared_recursive} helpers which
will have different definitions based on CONFIG_PROVE_LOCKING. Then all
other helper macros can be defined based on the above ones, which reduces
the amount of ifdefined code.
Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20130708212350.6DD1931C15E@corp2gmr1-1.hot.corp.google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
This adds some extra functions to deal with rcu.
reservation_object_get_fences_rcu() will obtain the list of shared
and exclusive fences without obtaining the ww_mutex.
reservation_object_wait_timeout_rcu() will wait on all fences of the
reservation_object, without obtaining the ww_mutex.
reservation_object_test_signaled_rcu() will test if all fences of the
reservation_object are signaled without using the ww_mutex.
reservation_object_get_excl and reservation_object_get_list require
the reservation object to be held, updating requires
write_seqcount_begin/end. If only the exclusive fence is needed,
rcu_dereference followed by fence_get_rcu can be used, if the shared
fences are needed it's recommended to use the supplied functions.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Reviewed-By: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
Move the list of shared fences to a struct, and return it in
reservation_object_get_list().
Add reservation_object_get_excl to get the exclusive fence.
Add reservation_object_reserve_shared(), which reserves space
in the reservation_object for 1 more shared fence.
reservation_object_add_shared_fence() and
reservation_object_add_excl_fence() are used to assign a new
fence to a reservation_object pointer, to complete a reservation.
Changes since v1:
- Add reservation_object_get_excl, reorder code a bit.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
Thanks to Fengguang Wu for spotting a missing static cast.
v2:
- Kill unused variable need_shared.
v3:
- Clarify the BUG() in dma_buf_release some more. (Rob Clark)
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Chanho Park <chanho61.park@samsung.com>
Conflicts:
drivers/dma-buf/dma-buf.c
Change-Id: I6c0d192dfd53809a16d3564e3863c1d1f0f348c7
|
|
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
Move the definitions for wound/wait mutexes out to a separate
header, ww_mutex.h. This reduces clutter in mutex.h, and
increases readability.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Cc: Dave Airlie <airlied@gmail.com>
Link: http://lkml.kernel.org/r/51D675DC.3000907@canonical.com
[ Tidied up the code a bit. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
This allows reservation objects to be used in dma-buf. it's required
for implementing polling support on the fences that belong to a dma-buf.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Acked-by: Mauro Carvalho Chehab <m.chehab@samsung.com> #drivers/media/v4l2-core/
Acked-by: Thomas Hellstrom <thellstrom@vmware.com> #drivers/gpu/drm/ttm
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Vincent Stehlé <vincent.stehle@laposte.net> #drivers/gpu/drm/armada/
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Chanho Park <chanho61.park@samsung.com>
Conflicts:
drivers/gpu/drm/armada/armada_gem.c
drivers/gpu/drm/drm_prime.c
drivers/gpu/drm/exynos/exynos_drm_dmabuf.c
drivers/gpu/drm/i915/i915_gem_dmabuf.c
drivers/gpu/drm/nouveau/nouveau_drm.c
drivers/gpu/drm/nouveau/nouveau_gem.h
drivers/gpu/drm/nouveau/nouveau_prime.c
drivers/gpu/drm/radeon/radeon_drv.c
drivers/gpu/drm/tegra/gem.c
drivers/gpu/drm/ttm/ttm_object.c
drivers/staging/android/ion/ion.c
Change-Id: I44fbb1f41500deaf9067eb5d7e1c6ed758231d69
|
|
... not only when the dma-buf is freshly created. In contrived
examples someone else could have exported/imported the dma-buf already
and handed us the gem object with a flink name. If such on object gets
reexported as a dma_buf we won't have it in the handle cache already,
which breaks the guarantee that for dma-buf imports we always hand
back an existing handle if there is one.
This is exercised by igt/prime_self_import/with_one_bo_two_files
Now if we extend the locked sections just a notch more we can also
plug th racy buf/handle cache setup in handle_to_fd:
If evil userspace races a concurrent gem close against a prime export
operation we can end up tearing down the gem handle before the dma buf
handle cache is set up. When handle_to_fd gets around to adding the
handle to the cache there will be no one left to clean it up,
effectily leaking the bo (and the dma-buf, since the handle cache
holds a ref on the dma-buf):
Thread A Thread B
handle_to_fd:
lookup gem object from handle
creates new dma_buf
gem_close on the same handle
obj->dma_buf is set, but file priv buf
handle cache has no entry
obj->handle_count drops to 0
drm_prime_add_buf_handle sets up the handle cache
-> We have a dma-buf reference in the handle cache, but since the
handle_count of the gem object already dropped to 0 no on will clean
it up. When closing the drm device fd we'll hit the WARN_ON in
drm_prime_destroy_file_private.
The important change is to extend the critical section of the
filp->prime.lock to cover the gem handle lookup. This serializes with
a concurrent gem handle close.
This leak is exercised by igt/prime_self_import/export-vs-gem_close-race
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
|
|
... and move it to the top of the function to avoid a forward
declaration.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
|
|
The export dma-buf cache is semantically similar to an flink name. So
semantically it makes sense to treat it the same and remove the name
(i.e. the dma_buf pointer) and its references when the last gem handle
disappears.
Again we need to be careful, but double so: Not just could someone
race and export with a gem close ioctl (so we need to recheck
obj->handle_count again when assigning the new name), but multiple
exports can also race against each another. This is prevented by
holding the dev->object_name_lock across the entire section which
touches obj->dma_buf.
With the new scheme we also need to reinstate the obj->dma_buf link at
import time (in case the only reference userspace has held in-between
was through the dma-buf fd and not through any native gem handle). For
simplicity we don't check whether it's a native object but
unconditionally set up that link - with the new scheme of removing the
obj->dma_buf reference when the last handle disappears we can do that.
To make it clear that this is not just for exported buffers anymore
als rename it from export_dma_buf to dma_buf.
To make sure that now one can race a fd_to_handle or handle_to_fd with
gem_close we use the same tricks as in flink of extending the
dev->object_name_locking critical section. With this change we finally
have a guaranteed 1:1 relationship (at least for native objects)
between gem objects and dma-bufs, even accounting for races (which can
happen since the dma-buf itself holds a reference while in-flight).
This prevent igt/prime_self_import/export-vs-gem_close-race from
Oopsing the kernel. There is still a leak though since the per-file
priv dma-buf/handle cache handling is racy. That will be fixed in a
later patch.
v2: Remove the bogus dma_buf_put from the export_and_register_object
failure path if we've raced with the handle count dropping to 0.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Chanho Park <chanho61.park@samsung.com>
Conflicts:
drivers/gpu/drm/drm_gem.c
Change-Id: I915b0e73cedffa0ba358cf00510e19dccfcb4703
|
|
This adds to call low-level mmap() from prime helpers.
Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
|
|
Prevents buffers from being pinned forever.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Chanho Park <chanho61.park@samsung.com>
Conflicts:
drivers/gpu/drm/drm_prime.c
Change-Id: I220c7924a9b08a13646fcc43c80cd9c031dd2d79
|
|
This type of fence can be used with hardware synchronization for simple
hardware that can block execution until the condition
(dma_buf[offset] - value) >= 0 has been met when WAIT_GEQUAL is used,
or (dma_buf[offset] != 0) has been met when WAIT_NONZERO is set.
A software fallback still has to be provided in case the fence is used
with a device that doesn't support this mechanism. It is useful to expose
this for graphics cards that have an op to support this.
Some cards like i915 can export those, but don't have an option to wait,
so they need the software fallback.
I extended the original patch by Rob Clark.
v1: Original
v2: Renamed from bikeshed to seqno, moved into dma-fence.c since
not much was left of the file. Lots of documentation added.
v3: Use fence_ops instead of custom callbacks. Moved to own file
to avoid circular dependency between dma-buf.h and fence.h
v4: Add spinlock pointer to seqno_fence_init
v5: Add condition member to allow wait for != 0.
Fix small style errors pointed out by checkpatch.
v6: Move to a separate file. Fix up api changes in fences.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Reviewed-by: Rob Clark <robdclark@gmail.com> #v4
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
A fence can be attached to a buffer which is being filled or consumed
by hw, to allow userspace to pass the buffer without waiting to another
device. For example, userspace can call page_flip ioctl to display the
next frame of graphics after kicking the GPU but while the GPU is still
rendering. The display device sharing the buffer with the GPU would
attach a callback to get notified when the GPU's rendering-complete IRQ
fires, to update the scan-out address of the display, without having to
wake up userspace.
A driver must allocate a fence context for each execution ring that can
run in parallel. The function for this takes an argument with how many
contexts to allocate:
+ fence_context_alloc()
A fence is transient, one-shot deal. It is allocated and attached
to one or more dma-buf's. When the one that attached it is done, with
the pending operation, it can signal the fence:
+ fence_signal()
To have a rough approximation whether a fence is fired, call:
+ fence_is_signaled()
The dma-buf-mgr handles tracking, and waiting on, the fences associated
with a dma-buf.
The one pending on the fence can add an async callback:
+ fence_add_callback()
The callback can optionally be cancelled with:
+ fence_remove_callback()
To wait synchronously, optionally with a timeout:
+ fence_wait()
+ fence_wait_timeout()
When emitting a fence, call:
+ trace_fence_emit()
To annotate that a fence is blocking on another fence, call:
+ trace_fence_annotate_wait_on(fence, on_fence)
A default software-only implementation is provided, which can be used
by drivers attaching a fence to a buffer when they have no other means
for hw sync. But a memory backed fence is also envisioned, because it
is common that GPU's can write to, or poll on some memory location for
synchronization. For example:
fence = custom_get_fence(...);
if ((seqno_fence = to_seqno_fence(fence)) != NULL) {
dma_buf *fence_buf = seqno_fence->sync_buf;
get_dma_buf(fence_buf);
... tell the hw the memory location to wait ...
custom_wait_on(fence_buf, seqno_fence->seqno_ofs, fence->seqno);
} else {
/* fall-back to sw sync * /
fence_add_callback(fence, my_cb);
}
On SoC platforms, if some other hw mechanism is provided for synchronizing
between IP blocks, it could be supported as an alternate implementation
with it's own fence ops in a similar way.
enable_signaling callback is used to provide sw signaling in case a cpu
waiter is requested or no compatible hardware signaling could be used.
The intention is to provide a userspace interface (presumably via eventfd)
later, to be used in conjunction with dma-buf's mmap support for sw access
to buffers (or for userspace apps that would prefer to do their own
synchronization).
v1: Original
v2: After discussion w/ danvet and mlankhorst on #dri-devel, we decided
that dma-fence didn't need to care about the sw->hw signaling path
(it can be handled same as sw->sw case), and therefore the fence->ops
can be simplified and more handled in the core. So remove the signal,
add_callback, cancel_callback, and wait ops, and replace with a simple
enable_signaling() op which can be used to inform a fence supporting
hw->hw signaling that one or more devices which do not support hw
signaling are waiting (and therefore it should enable an irq or do
whatever is necessary in order that the CPU is notified when the
fence is passed).
v3: Fix locking fail in attach_fence() and get_fence()
v4: Remove tie-in w/ dma-buf.. after discussion w/ danvet and mlankorst
we decided that we need to be able to attach one fence to N dma-buf's,
so using the list_head in dma-fence struct would be problematic.
v5: [ Maarten Lankhorst ] Updated for dma-bikeshed-fence and dma-buf-manager.
v6: [ Maarten Lankhorst ] I removed dma_fence_cancel_callback and some comments
about checking if fence fired or not. This is broken by design.
waitqueue_active during destruction is now fatal, since the signaller
should be holding a reference in enable_signalling until it signalled
the fence. Pass the original dma_fence_cb along, and call __remove_wait
in the dma_fence_callback handler, so that no cleanup needs to be
performed.
v7: [ Maarten Lankhorst ] Set cb->func and only enable sw signaling if
fence wasn't signaled yet, for example for hardware fences that may
choose to signal blindly.
v8: [ Maarten Lankhorst ] Tons of tiny fixes, moved __dma_fence_init to
header and fixed include mess. dma-fence.h now includes dma-buf.h
All members are now initialized, so kmalloc can be used for
allocating a dma-fence. More documentation added.
v9: Change compiler bitfields to flags, change return type of
enable_signaling to bool. Rework dma_fence_wait. Added
dma_fence_is_signaled and dma_fence_wait_timeout.
s/dma// and change exports to non GPL. Added fence_is_signaled and
fence_enable_sw_signaling calls, add ability to override default
wait operation.
v10: remove event_queue, use a custom list, export try_to_wake_up from
scheduler. Remove fence lock and use a global spinlock instead,
this should hopefully remove all the locking headaches I was having
on trying to implement this. enable_signaling is called with this
lock held.
v11:
Use atomic ops for flags, lifting the need for some spin_lock_irqsaves.
However I kept the guarantee that after fence_signal returns, it is
guaranteed that enable_signaling has either been called to completion,
or will not be called any more.
Add contexts and seqno to base fence implementation. This allows you
to wait for less fences, by testing for seqno + signaled, and then only
wait on the later fence.
Add FENCE_TRACE, FENCE_WARN, and FENCE_ERR. This makes debugging easier.
An CONFIG_DEBUG_FENCE will be added to turn off the FENCE_TRACE
spam, and another runtime option can turn it off at runtime.
v12:
Add CONFIG_FENCE_TRACE. Add missing documentation for the fence->context
and fence->seqno members.
v13:
Fixup CONFIG_FENCE_TRACE kconfig description.
Move fence_context_alloc to fence.
Simplify fence_later.
Kill priv member to fence_cb.
v14:
Remove priv argument from fence_add_callback, oops!
v15:
Remove priv from documentation.
Explicitly include linux/atomic.h.
v16:
Add trace events.
Import changes required by android syncpoints.
v17:
Use wake_up_state instead of try_to_wake_up. (Colin Cross)
Fix up commit description for seqno_fence. (Rob Clark)
v18:
Rename release_fence to fence_release.
Move to drivers/dma-buf/.
Rename __fence_is_signaled and __fence_signal to *_locked.
Rename __fence_init to fence_init.
Make fence_default_wait return a signed long, and fix wait ops too.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com> #use smp_mb__before_atomic()
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Chanho Park <chanho61.park@samsung.com>
Conflicts:
drivers/base/Kconfig
Change-Id: Ie62c8c33a0cb7ca3df596f47ef328c33c4468139
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Russell King observed 'wierd' looking output from debugfs, and also suggested
better ways of getting device names (use KBUILD_MODNAME, dev_name())
This patch addresses these issues to make the debugfs output correct and better
looking.
While at it, replace seq_printf with seq_puts to remove the checkpatch.pl
warnings.
Reported-by: Russell King - ARM Linux <linux@arm.linux.org.uk>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
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This adds support for a generic reservations framework that can be
hooked up to ttm and dma-buf and allows easy sharing of reservations
across devices.
The idea is that a dma-buf and ttm object both will get a pointer
to a struct reservation_object, which has to be reserved before
anything is done with the contents of the dma-buf.
Changes since v1:
- Fix locking issue in ticket_reserve, which could cause mutex_unlock
to be called too many times.
Changes since v2:
- All fence related calls and members have been taken out for now,
what's left is the bare minimum to be useful for ttm locking conversion.
Changes since v3:
- Removed helper functions too. The documentation has an example
implementation for locking. With the move to ww_mutex there is no
need to have much logic any more.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
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This reverts commit 7a9958fedb90ef4000b6461d77a5c6dfd795c1c1.
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