block: blk-mq: support draining mq queue
blk_mq_drain_queue() is introduced so that we can drain
mq queue inside blk_cleanup_queue().
Also don't accept new requests any more if queue is marked
as dying.
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/block/blk-exec.c b/block/blk-exec.c
index c3edf9d..bbfc072 100644
--- a/block/blk-exec.c
+++ b/block/blk-exec.c
@@ -60,6 +60,10 @@
rq->rq_disk = bd_disk;
rq->end_io = done;
+ /*
+ * don't check dying flag for MQ because the request won't
+ * be resued after dying flag is set
+ */
if (q->mq_ops) {
blk_mq_insert_request(q, rq, true);
return;