From: Keith Busch kbusch@kernel.org

mainline inclusion from mainline-5.8-rc1 commit 7b11eab041dacfeaaa6d27d9183b247a995bc16d category: bugfix bugzilla: 175150 CVE: NA

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Drivers may need to bypass error injection for error recovery. Rename __blk_mq_complete_request() to blk_mq_force_complete_rq() and export that function so drivers may skip potential fake timeouts after they've reclaimed lost requests.

Signed-off-by: Keith Busch kbusch@kernel.org Reviewed-by: Daniel Wagner dwagner@suse.de Signed-off-by: Jens Axboe axboe@kernel.dk

Conflicts: block/blk-mq.c include/linux/blk-mq.h [ Non bugfix patch c7bb9ad1744ea14e6("block: get rid of q->softirq_done_fn()") is not applied. ]

Signed-off-by: Zhihao Cheng chengzhihao1@huawei.com Reviewed-by: Hou Tao houtao1@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- block/blk-mq.c | 15 +++++++++++++-- include/linux/blk-mq.h | 1 + 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/block/blk-mq.c b/block/blk-mq.c index dc96754abc2cd..b5b41b9a72294 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -582,7 +582,17 @@ static void __blk_mq_complete_request_remote(void *data) rq->q->softirq_done_fn(rq); }

-static void __blk_mq_complete_request(struct request *rq) +/** + * blk_mq_force_complete_rq() - Force complete the request, bypassing any error + * injection that could drop the completion. + * @rq: Request to be force completed + * + * Drivers should use blk_mq_complete_request() to complete requests in their + * normal IO path. For timeout error recovery, drivers may call this forced + * completion routine after they've reclaimed timed out requests to bypass + * potentially subsequent fake timeouts. + */ +void blk_mq_force_complete_rq(struct request *rq) { struct blk_mq_ctx *ctx = rq->mq_ctx; bool shared = false; @@ -612,6 +622,7 @@ static void __blk_mq_complete_request(struct request *rq) } put_cpu(); } +EXPORT_SYMBOL_GPL(blk_mq_force_complete_rq);

static void hctx_unlock(struct blk_mq_hw_ctx *hctx, int srcu_idx) __releases(hctx->srcu) @@ -645,7 +656,7 @@ void blk_mq_complete_request(struct request *rq) { if (unlikely(blk_should_fake_timeout(rq->q))) return; - __blk_mq_complete_request(rq); + blk_mq_force_complete_rq(rq); } EXPORT_SYMBOL(blk_mq_complete_request);

diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index 730de600075b5..f81bbcdbce0f8 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -299,6 +299,7 @@ void blk_mq_add_to_requeue_list(struct request *rq, bool at_head, void blk_mq_kick_requeue_list(struct request_queue *q); void blk_mq_delay_kick_requeue_list(struct request_queue *q, unsigned long msecs); void blk_mq_complete_request(struct request *rq); +void blk_mq_force_complete_rq(struct request *rq); bool blk_mq_bio_list_merge(struct request_queue *q, struct list_head *list, struct bio *bio); bool blk_mq_queue_stopped(struct request_queue *q);