From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753374Ab1JUD44 (ORCPT ); Thu, 20 Oct 2011 23:56:56 -0400 Received: from mail-yx0-f174.google.com ([209.85.213.174]:61184 "EHLO mail-yx0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753306Ab1JUD4z (ORCPT ); Thu, 20 Oct 2011 23:56:55 -0400 From: Tejun Heo To: axboe@kernel.dk, vgoyal@redhat.com, jgarzik@pobox.com, davem@davemloft.net Cc: linux-kernel@vger.kernel.org, ctalbott@google.com, rni@google.com, Tejun Heo Subject: [PATCH 6/6] block: add missing blk_queue_dead() checks Date: Thu, 20 Oct 2011 20:56:40 -0700 Message-Id: <1319169400-15706-7-git-send-email-tj@kernel.org> X-Mailer: git-send-email 1.7.3.1 In-Reply-To: <1319169400-15706-1-git-send-email-tj@kernel.org> References: <1319169400-15706-1-git-send-email-tj@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 Cc: Jens Axboe --- block/blk-core.c | 21 +++++++++++++++++++++ block/blk-exec.c | 5 ++++- 2 files changed, 25 insertions(+), 1 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index 53e36c6..c195298 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1724,6 +1724,10 @@ 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 @@ -2696,6 +2700,14 @@ 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 * this lock). @@ -2771,6 +2783,15 @@ 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 d11c0b8..727abb1 100644 --- a/block/blk-exec.c +++ b/block/blk-exec.c @@ -51,7 +51,10 @@ void blk_execute_rq_nowait(struct request_queue *q, struct gendisk *bd_disk, int where = at_head ? ELEVATOR_INSERT_FRONT : ELEVATOR_INSERT_BACK; unsigned long flags; + spin_lock_irqsave(q->queue_lock, flags); + if (unlikely(blk_queue_dead(q))) { + spin_unlock_irqrestore(q->queue_lock, flags); rq->errors = -ENXIO; if (rq->end_io) rq->end_io(rq, rq->errors); @@ -60,12 +63,12 @@ void blk_execute_rq_nowait(struct request_queue *q, struct gendisk *bd_disk, rq->rq_disk = bd_disk; rq->end_io = done; - spin_lock_irqsave(q->queue_lock, flags); elv_add_request(q, rq, where); blk_run_queue_async(q); /* the queue is stopped so it won't be run */ if (rq->cmd_type == REQ_TYPE_PM_RESUME) q->request_fn(q); + spin_unlock_irqrestore(q->queue_lock, flags); } EXPORT_SYMBOL_GPL(blk_execute_rq_nowait); -- 1.7.3.1