[PATCH 03/13] loop: Enable context analysis

Let the compiler verify __must_hold(), __guarded_by() etc. Suppress the
warnings reported for loop_global_{,un}_lock*() by adding a
__context_unsafe() annotation. Both __context_unsafe() annotations will be
removed by a later patch.

Signed-off-by: Bart Van Assche <[email protected]>
---
 drivers/block/Makefile | 2 ++
 drivers/block/loop.c   | 4 ++++
 2 files changed, 6 insertions(+)

diff --git a/drivers/block/Makefile b/drivers/block/Makefile
index 2d8096eb8cdf..d4555949cc3c 100644
--- a/drivers/block/Makefile
+++ b/drivers/block/Makefile
@@ -6,6 +6,8 @@
 # Rewritten to use lists instead of if-statements.
 # 
 
+CONTEXT_ANALYSIS_loop.o := y
+
 # needed for trace events
 ccflags-y				+= -I$(src)
 
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 4315c36d4042..638d97293a79 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -108,6 +108,8 @@ static DEFINE_MUTEX(loop_validate_mutex);
  * loop_configure()/loop_change_fd()/__loop_clr_fd() calls.
  */
 static int loop_global_lock_killable(struct loop_device *lo, bool global)
+	__cond_acquires(0, &lo->lo_mutex)
+	__context_unsafe(conditional locking)
 {
 	int err;
 
@@ -129,6 +131,8 @@ static int loop_global_lock_killable(struct loop_device *lo, bool global)
  * @global: true if @lo was about to bind another "struct loop_device", false otherwise
  */
 static void loop_global_unlock(struct loop_device *lo, bool global)
+	__releases(&lo->lo_mutex)
+	__context_unsafe(conditional locking)
 {
 	mutex_unlock(&lo->lo_mutex);
 	if (global)