[PATCH v4 01/12] block: Annotate the queue limits functions

[Bart Van Assche <bvanassche@acm.org>]

Let the thread-safety checker verify whether every start of a queue
limits update is followed by a call to a function that finishes a queue
limits update.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
---
 include/linux/blkdev.h | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 890128cdea1c..8651af4fe9d7 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1093,15 +1093,17 @@ static inline unsigned int blk_boundary_sectors_left(sector_t offset,
  */
 static inline struct queue_limits
 queue_limits_start_update(struct request_queue *q)
+	__acquires(&q->limits_lock)
 {
 	mutex_lock(&q->limits_lock);
 	return q->limits;
 }
 int queue_limits_commit_update_frozen(struct request_queue *q,
-		struct queue_limits *lim);
+		struct queue_limits *lim) __releases(&q->limits_lock);
 int queue_limits_commit_update(struct request_queue *q,
-		struct queue_limits *lim);
-int queue_limits_set(struct request_queue *q, struct queue_limits *lim);
+		struct queue_limits *lim) __releases(&q->limits_lock);
+int queue_limits_set(struct request_queue *q, struct queue_limits *lim)
+	__must_not_hold(&q->limits_lock);
 int blk_validate_limits(struct queue_limits *lim);
 
 /**
@@ -1113,6 +1115,7 @@ int blk_validate_limits(struct queue_limits *lim);
  * starting update.
  */
 static inline void queue_limits_cancel_update(struct request_queue *q)
+	__releases(&q->limits_lock)
 {
 	mutex_unlock(&q->limits_lock);
 }