Commit f688012c authored by Keith Busch's avatar Keith Busch Committed by Yang Yingliang
Browse files

blk-mq: blk-mq: provide forced completion method 



mainline inclusion
from mainline-5.8-rc1
commit 7b11eab0
category: bugfix
bugzilla: 175150
CVE: NA

---------------------------

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: default avatarKeith Busch <kbusch@kernel.org>
Reviewed-by: default avatarDaniel Wagner <dwagner@suse.de>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>

Conflicts:
	block/blk-mq.c
	include/linux/blk-mq.h
	[ Non bugfix patch c7bb9ad1("block: get rid of
	  q->softirq_done_fn()") is not applied. ]

Signed-off-by: default avatarZhihao Cheng <chengzhihao1@huawei.com>
Reviewed-by: default avatarHou Tao <houtao1@huawei.com>
Signed-off-by: default avatarYang Yingliang <yangyingliang@huawei.com>
parent 0875a4c4

block/blk-mq.c

+13 −2
Original line number Diff line number Diff line
@@ -579,7 +579,17 @@ 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;
@@ -609,6 +619,7 @@ 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)
@@ -642,7 +653,7 @@ 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);

include/linux/blk-mq.h

+1 −0
Original line number Diff line number Diff line
@@ -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);