Commit 8ba61435 authored by Tejun Heo's avatar Tejun Heo Committed by Jens Axboe
Browse files

block: add missing blk_queue_dead() checks 



blk_insert_cloned_request(), blk_execute_rq_nowait() and
blk_flush_plug_list() either didn't check whether the queue was dead
or did it without holding queue_lock.  Update them so that dead state
is checked while holding queue_lock.

AFAICS, this plugs all holes (requeue doesn't matter as the request is
transitioning atomically from in_flight to queued).

Signed-off-by: default avatarTejun Heo <tj@kernel.org>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 481a7d64

block/blk-core.c

+21 −0
Original line number Diff line number Diff line
@@ -1731,6 +1731,10 @@ int blk_insert_cloned_request(struct request_queue *q, struct request *rq) 
		return -EIO;



	spin_lock_irqsave(q->queue_lock, flags);

	if (unlikely(blk_queue_dead(q))) {

		spin_unlock_irqrestore(q->queue_lock, flags);

		return -ENODEV;

	}



	/*

	 * Submitting request must be dequeued before calling this function
@@ -2704,6 +2708,14 @@ static void queue_unplugged(struct request_queue *q, unsigned int depth, 
{

	trace_block_unplug(q, depth, !from_schedule);



	/*

	 * Don't mess with dead queue.

	 */

	if (unlikely(blk_queue_dead(q))) {

		spin_unlock(q->queue_lock);

		return;

	}



	/*

	 * If we are punting this to kblockd, then we can safely drop

	 * the queue_lock before waking kblockd (which needs to take
@@ -2780,6 +2792,15 @@ void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule) 
			depth = 0;

			spin_lock(q->queue_lock);

		}



		/*

		 * Short-circuit if @q is dead

		 */

		if (unlikely(blk_queue_dead(q))) {

			__blk_end_request_all(rq, -ENODEV);

			continue;

		}



		/*

		 * rq is already accounted, so use raw insert

		 */

block/blk-exec.c

+4 −2
Original line number Diff line number Diff line
@@ -50,7 +50,11 @@ void blk_execute_rq_nowait(struct request_queue *q, struct gendisk *bd_disk, 
{

	int where = at_head ? ELEVATOR_INSERT_FRONT : ELEVATOR_INSERT_BACK;



	WARN_ON(irqs_disabled());

	spin_lock_irq(q->queue_lock);



	if (unlikely(blk_queue_dead(q))) {

		spin_unlock_irq(q->queue_lock);

		rq->errors = -ENXIO;

		if (rq->end_io)

			rq->end_io(rq, rq->errors);
@@ -59,8 +63,6 @@ void blk_execute_rq_nowait(struct request_queue *q, struct gendisk *bd_disk, 


	rq->rq_disk = bd_disk;

	rq->end_io = done;

	WARN_ON(irqs_disabled());

	spin_lock_irq(q->queue_lock);

	__elv_add_request(q, rq, where);

	__blk_run_queue(q);

	/* the queue is stopped so it won't be run */

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