[PATCH 01/12] blk-mq: Do not invoke .queue_rq() for a stopped queue

[Hannes Reinecke]

On 10/27/2016 12:50 AM, Bart Van Assche wrote:
> The meaning of the BLK_MQ_S_STOPPED flag is "do not call
> .queue_rq()". Hence modify blk_mq_make_request() such that requests
> are queued instead of issued if a queue has been stopped.
> 
> Reported-by: Ming Lei <tom.leiming at gmail.com>
> Signed-off-by: Bart Van Assche <bart.vanassche at sandisk.com>
> Reviewed-by: Christoph Hellwig <hch at lst.de>
> Reviewed-by: Ming Lei <tom.leiming at gmail.com>
> Cc: Hannes Reinecke <hare at suse.com>
> Cc: Sagi Grimberg <sagi at grimberg.me>
> Cc: Johannes Thumshirn <jthumshirn at suse.de>
> Cc: <stable at vger.kernel.org>
> ---
>  block/blk-mq.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/block/blk-mq.c b/block/blk-mq.c
> index ddc2eed..b5dcafb 100644
> --- a/block/blk-mq.c
> +++ b/block/blk-mq.c
> @@ -1332,9 +1332,9 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
>  		blk_mq_put_ctx(data.ctx);
>  		if (!old_rq)
>  			goto done;
> -		if (!blk_mq_direct_issue_request(old_rq, &cookie))
> -			goto done;
> -		blk_mq_insert_request(old_rq, false, true, true);
> +		if (test_bit(BLK_MQ_S_STOPPED, &data.hctx->state) ||
> +		    blk_mq_direct_issue_request(old_rq, &cookie) != 0)
> +			blk_mq_insert_request(old_rq, false, true, true);
>  		goto done;
>  	}
>  
> 
Reviewed-by: Hannes Reinecke <hare at suse.com>

Cheers,

Hannes
-- 
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