blk-mq: Do not invoke .queue_rq() for a stopped queue

commit bc27c01b5c46d3bfec42c96537c7a3fae0bb2cc4 upstream.

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@gmail.com>
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <tom.leiming@gmail.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/block/blk-mq.c b/block/blk-mq.c
index c3e461e..9f99a01 100644 (file)
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1313,9 +1313,9 @@ 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;
        }