[PATCH AUTOSEL 6.6 16/39] driver core: Add a guard() definition for the device_lock()

[Sasha Levin]

From: Dan Williams <dan.j.williams@xxxxxxxxx>

[ Upstream commit 134c6eaa6087d78c0e289931ca15ae7a5007670d ]

At present there are ~200 usages of device_lock() in the kernel. Some of
those usages lead to "goto unlock;" patterns which have proven to be
error prone. Define a "device" guard() definition to allow for those to
be cleaned up and prevent new ones from appearing.

Link: http://lore.kernel.org/r/657897453dda8_269bd29492@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx.notmuch
Link: http://lore.kernel.org/r/6577b0c2a02df_a04c5294bb@xxxxxxxxxxxxxxxxxxxxxxxxx.notmuch
Cc: Vishal Verma <vishal.l.verma@xxxxxxxxx>
Cc: Ira Weiny <ira.weiny@xxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Reviewed-by: Ira Weiny <ira.weiny@xxxxxxxxx>
Reviewed-by: Dave Jiang <dave.jiang@xxxxxxxxx>
Reviewed-by: Vishal Verma <vishal.l.verma@xxxxxxxxx>
Link: https://lore.kernel.org/r/170250854466.1522182.17555361077409628655.stgit@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 include/linux/device.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/include/linux/device.h b/include/linux/device.h
index 56d93a1ffb7b6..99496a0a5ddb3 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -1007,6 +1007,8 @@ static inline void device_unlock(struct device *dev)
 	mutex_unlock(&dev->mutex);
 }
 
+DEFINE_GUARD(device, struct device *, device_lock(_T), device_unlock(_T))
+
 static inline void device_lock_assert(struct device *dev)
 {
 	lockdep_assert_held(&dev->mutex);
-- 
2.43.0