Commit 8a0ac14b authored by Bart Van Assche's avatar Bart Van Assche Committed by Jens Axboe
Browse files

block: Move the queue_flag_*() functions from a public into a private header file 



This patch helps to avoid that new code gets introduced in block drivers
that manipulates queue flags without holding the queue lock when that
lock should be held.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Ming Lei <ming.lei@redhat.com>
Reviewed-by: default avatarJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: default avatarBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 1db2008b

block/blk.h

+69 −0
Original line number Diff line number Diff line
@@ -41,6 +41,75 @@ extern struct kmem_cache *request_cachep; 
extern struct kobj_type blk_queue_ktype;

extern struct ida blk_queue_ida;



/*

 * @q->queue_lock is set while a queue is being initialized. Since we know

 * that no other threads access the queue object before @q->queue_lock has

 * been set, it is safe to manipulate queue flags without holding the

 * queue_lock if @q->queue_lock == NULL. See also blk_alloc_queue_node() and

 * blk_init_allocated_queue().

 */

static inline void queue_lockdep_assert_held(struct request_queue *q)

{

	if (q->queue_lock)

		lockdep_assert_held(q->queue_lock);

}



static inline void queue_flag_set_unlocked(unsigned int flag,

					   struct request_queue *q)

{

	if (test_bit(QUEUE_FLAG_INIT_DONE, &q->queue_flags) &&

	    kref_read(&q->kobj.kref))

		lockdep_assert_held(q->queue_lock);

	__set_bit(flag, &q->queue_flags);

}



static inline void queue_flag_clear_unlocked(unsigned int flag,

					     struct request_queue *q)

{

	if (test_bit(QUEUE_FLAG_INIT_DONE, &q->queue_flags) &&

	    kref_read(&q->kobj.kref))

		lockdep_assert_held(q->queue_lock);

	__clear_bit(flag, &q->queue_flags);

}



static inline int queue_flag_test_and_clear(unsigned int flag,

					    struct request_queue *q)

{

	queue_lockdep_assert_held(q);



	if (test_bit(flag, &q->queue_flags)) {

		__clear_bit(flag, &q->queue_flags);

		return 1;

	}



	return 0;

}



static inline int queue_flag_test_and_set(unsigned int flag,

					  struct request_queue *q)

{

	queue_lockdep_assert_held(q);



	if (!test_bit(flag, &q->queue_flags)) {

		__set_bit(flag, &q->queue_flags);

		return 0;

	}



	return 1;

}



static inline void queue_flag_set(unsigned int flag, struct request_queue *q)

{

	queue_lockdep_assert_held(q);

	__set_bit(flag, &q->queue_flags);

}



static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)

{

	queue_lockdep_assert_held(q);

	__clear_bit(flag, &q->queue_flags);

}



static inline struct blk_flush_queue *blk_get_flush_queue(

		struct request_queue *q, struct blk_mq_ctx *ctx)

{

include/linux/blkdev.h

+0 −69
Original line number Diff line number Diff line
@@ -712,75 +712,6 @@ void blk_queue_flag_clear(unsigned int flag, struct request_queue *q); 
bool blk_queue_flag_test_and_set(unsigned int flag, struct request_queue *q);

bool blk_queue_flag_test_and_clear(unsigned int flag, struct request_queue *q);



/*

 * @q->queue_lock is set while a queue is being initialized. Since we know

 * that no other threads access the queue object before @q->queue_lock has

 * been set, it is safe to manipulate queue flags without holding the

 * queue_lock if @q->queue_lock == NULL. See also blk_alloc_queue_node() and

 * blk_init_allocated_queue().

 */

static inline void queue_lockdep_assert_held(struct request_queue *q)

{

	if (q->queue_lock)

		lockdep_assert_held(q->queue_lock);

}



static inline void queue_flag_set_unlocked(unsigned int flag,

					   struct request_queue *q)

{

	if (test_bit(QUEUE_FLAG_INIT_DONE, &q->queue_flags) &&

	    kref_read(&q->kobj.kref))

		lockdep_assert_held(q->queue_lock);

	__set_bit(flag, &q->queue_flags);

}



static inline void queue_flag_clear_unlocked(unsigned int flag,

					     struct request_queue *q)

{

	if (test_bit(QUEUE_FLAG_INIT_DONE, &q->queue_flags) &&

	    kref_read(&q->kobj.kref))

		lockdep_assert_held(q->queue_lock);

	__clear_bit(flag, &q->queue_flags);

}



static inline int queue_flag_test_and_clear(unsigned int flag,

					    struct request_queue *q)

{

	queue_lockdep_assert_held(q);



	if (test_bit(flag, &q->queue_flags)) {

		__clear_bit(flag, &q->queue_flags);

		return 1;

	}



	return 0;

}



static inline int queue_flag_test_and_set(unsigned int flag,

					  struct request_queue *q)

{

	queue_lockdep_assert_held(q);



	if (!test_bit(flag, &q->queue_flags)) {

		__set_bit(flag, &q->queue_flags);

		return 0;

	}



	return 1;

}



static inline void queue_flag_set(unsigned int flag, struct request_queue *q)

{

	queue_lockdep_assert_held(q);

	__set_bit(flag, &q->queue_flags);

}



static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)

{

	queue_lockdep_assert_held(q);

	__clear_bit(flag, &q->queue_flags);

}



#define blk_queue_tagged(q)	test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)

#define blk_queue_stopped(q)	test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)

#define blk_queue_dying(q)	test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)