From 8ba61435d73f2274e12d4d823fde06735e8f6a54 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 14 Dec 2011 00:33:37 +0100 Subject: [PATCH] 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: Tejun Heo Signed-off-by: Jens Axboe --- block/blk-core.c | 21 +++++++++++++++++++++ block/blk-exec.c | 6 ++++-- 2 files changed, 25 insertions(+), 2 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index c37e9e7c9d07..30add45a87ef 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -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 */ diff --git a/block/blk-exec.c b/block/blk-exec.c index 60532852b3ab..fb2cbd551621 100644 --- a/block/blk-exec.c +++ b/block/blk-exec.c @@ -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 */ -- 2.30.2