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| author | David Fries <David@Fries.net> | 2014-01-15 22:29:13 -0600 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-02-07 15:40:17 -0800 |
| commit | 421056987620fecb43c22c558e127085c406b7ba (patch) | |
| tree | 12b735281e22323f036b87f010d11ea8addb2af0 /drivers/w1 | |
| parent | 6b355b33a64fd6d8ead2b838ec16fb9b551f71e8 (diff) | |
| download | linux-rpi3-421056987620fecb43c22c558e127085c406b7ba.tar.gz linux-rpi3-421056987620fecb43c22c558e127085c406b7ba.tar.bz2 linux-rpi3-421056987620fecb43c22c558e127085c406b7ba.zip | |
w1: fixup search to support abort from netlink
Before 63706172f33 "rework kthread_stop()" kthread_should_stop()
always returned false when called from a non-kthread task, after it
would oops as a non-kthread didn't have that structure and netlink was
calling search from a thread which wasn't a kthread. 9d1817cab2f030
"w1: fix oops when w1_search is called from netlink connector",
modified the code to avoid calling kthread_stop from a netlink thread.
Introduce a w1_master flag and bit W1_ABORT_SEARCH to identify abort
to cleanly support both kthread and netlink search abort. A search
can take seconds to run, so it is important to abort early if the
hardware is removed in the middle of a search.
Signed-off-by: David Fries <David@Fries.net>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Marcin Jurkowski <marcin1j@gmail.com>
Cc: Josh Boyer <jwboyer@gmail.com>
Cc: Sven Geggus <lists@fuchsschwanzdomain.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/w1')
| -rw-r--r-- | drivers/w1/w1.c | 3 | ||||
| -rw-r--r-- | drivers/w1/w1.h | 10 | ||||
| -rw-r--r-- | drivers/w1/w1_int.c | 2 |
3 files changed, 13 insertions, 2 deletions
diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c index 66efa96c4603..67b6d5fb25bc 100644 --- a/drivers/w1/w1.c +++ b/drivers/w1/w1.c @@ -960,8 +960,7 @@ void w1_search(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb tmp64 = (triplet_ret >> 2); rn |= (tmp64 << i); - /* ensure we're called from kthread and not by netlink callback */ - if (!dev->priv && kthread_should_stop()) { + if (test_bit(W1_ABORT_SEARCH, &dev->flags)) { mutex_unlock(&dev->bus_mutex); dev_dbg(&dev->dev, "Abort w1_search\n"); return; diff --git a/drivers/w1/w1.h b/drivers/w1/w1.h index ca8081a101d6..bc329d2bba28 100644 --- a/drivers/w1/w1.h +++ b/drivers/w1/w1.h @@ -155,6 +155,14 @@ struct w1_bus_master u8, w1_slave_found_callback); }; +/** + * enum w1_master_flags - bitfields used in w1_master.flags + * @W1_ABORT_SEARCH: abort searching early on shutdown + */ +enum w1_master_flags { + W1_ABORT_SEARCH = 0, +}; + struct w1_master { struct list_head w1_master_entry; @@ -178,6 +186,8 @@ struct w1_master /** 5V strong pullup duration in milliseconds, zero disabled. */ int pullup_duration; + long flags; + struct task_struct *thread; struct mutex mutex; struct mutex bus_mutex; diff --git a/drivers/w1/w1_int.c b/drivers/w1/w1_int.c index 590bd8a7cd1b..423f3c2b9e7d 100644 --- a/drivers/w1/w1_int.c +++ b/drivers/w1/w1_int.c @@ -172,6 +172,7 @@ int w1_add_master_device(struct w1_bus_master *master) #if 0 /* Thread cleanup code, not required currently. */ err_out_kill_thread: + set_bit(W1_ABORT_SEARCH, &dev->flags); kthread_stop(dev->thread); #endif err_out_rm_attr: @@ -187,6 +188,7 @@ void __w1_remove_master_device(struct w1_master *dev) struct w1_netlink_msg msg; struct w1_slave *sl, *sln; + set_bit(W1_ABORT_SEARCH, &dev->flags); kthread_stop(dev->thread); mutex_lock(&w1_mlock); |