[PATCH v2 1/2] virtio-blk: set req->state to MQ_RQ_COMPLETE after polling I/O is finished

[Suwan Kim <suwan.kim027@gmail.com>]

Driver should set req->state to MQ_RQ_COMPLETE after it finishes to process
req. But virtio-blk doesn't set MQ_RQ_COMPLETE after virtblk_poll() handles
req and req->state still remains MQ_RQ_IN_FLIGHT. Fortunately so far there
is no issue about it because blk_mq_end_request_batch() sets req->state to
MQ_RQ_IDLE.

In this patch, virblk_poll() calls blk_mq_complete_request_remote() to set
req->state to MQ_RQ_COMPLETE before it adds req to a batch completion list.
So it properly sets req->state after polling I/O is finished.

Fixes: 4e0400525691 ("virtio-blk: support polling I/O")
Signed-off-by: Suwan Kim <suwan.kim027@gmail.com>
---
 drivers/block/virtio_blk.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 19da5defd734..75ee51aba964 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -858,9 +858,10 @@ static int virtblk_poll(struct blk_mq_hw_ctx *hctx, struct io_comp_batch *iob)
 		struct request *req = blk_mq_rq_from_pdu(vbr);
 
 		found++;
-		if (!blk_mq_add_to_batch(req, iob, vbr->status,
+		if (!blk_mq_complete_request_remote(req) &&
+		    !blk_mq_add_to_batch(req, iob, vbr->status,
 						virtblk_complete_batch))
-			blk_mq_complete_request(req);
+			virtblk_request_done(req);
 	}
 
 	if (found)
-- 
2.26.3