block: change flush sequence list addition back to front add

Commit 18741986 inadvertently changed the rq flush insertion
from a head to a tail insertion. Fix that back up.

Signed-off-by: Mike Snitzer <msnitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/block/blk-flush.c b/block/blk-flush.c
index f598f794c3c679e8c7904bb88284c96434123d66..43e6b4755e9a7e74e05479a83d42fbd88762e9f4 100644 (file)
--- a/block/blk-flush.c
+++ b/block/blk-flush.c
@@ -140,14 +140,17 @@ static void mq_flush_run(struct work_struct *work)
        blk_mq_insert_request(rq, false, true, false);
 }
 
-static bool blk_flush_queue_rq(struct request *rq)
+static bool blk_flush_queue_rq(struct request *rq, bool add_front)
 {
        if (rq->q->mq_ops) {
                INIT_WORK(&rq->mq_flush_work, mq_flush_run);
                kblockd_schedule_work(rq->q, &rq->mq_flush_work);
                return false;
        } else {
-               list_add_tail(&rq->queuelist, &rq->q->queue_head);
+               if (add_front)
+                       list_add(&rq->queuelist, &rq->q->queue_head);
+               else
+                       list_add_tail(&rq->queuelist, &rq->q->queue_head);
                return true;
        }
 }
@@ -193,7 +196,7 @@ static bool blk_flush_complete_seq(struct request *rq, unsigned int seq,
 
        case REQ_FSEQ_DATA:
                list_move_tail(&rq->flush.list, &q->flush_data_in_flight);
-               queued = blk_flush_queue_rq(rq);
+               queued = blk_flush_queue_rq(rq, true);
                break;
 
        case REQ_FSEQ_DONE:
@@ -326,7 +329,7 @@ static bool blk_kick_flush(struct request_queue *q)
        q->flush_rq->rq_disk = first_rq->rq_disk;
        q->flush_rq->end_io = flush_end_io;
 
-       return blk_flush_queue_rq(q->flush_rq);
+       return blk_flush_queue_rq(q->flush_rq, false);
 }
 
 static void flush_data_end_io(struct request *rq, int error)