blk-flush: fix rq->flush.seq for post-flush requests

If the policy == (REQ_FSEQ_DATA | REQ_FSEQ_POSTFLUSH), it means that the
data sequence and post-flush sequence need to be done for this request.

The rq->flush.seq should record what sequences have been done (or don't
need to be done). So in this case, pre-flush doesn't need to be done,
we should init rq->flush.seq to REQ_FSEQ_PREFLUSH not REQ_FSEQ_POSTFLUSH.

Fixes: 615939a2ae73 ("blk-mq: defer to the normal submission path for post-flush requests")
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230717040058.3993930-3-chengming.zhou@linux.dev
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/block/blk-flush.c b/block/blk-flush.c
index 8220517c2d67dad4e09457b7dd1303e4015a6844..fdc489e0ea16257b1aa9a3d75265c3890e33f925 100644 (file)
--- a/block/blk-flush.c
+++ b/block/blk-flush.c
@@ -443,7 +443,7 @@ bool blk_insert_flush(struct request *rq)
                 * the post flush, and then just pass the command on.
                 */
                blk_rq_init_flush(rq);
-               rq->flush.seq |= REQ_FSEQ_POSTFLUSH;
+               rq->flush.seq |= REQ_FSEQ_PREFLUSH;
                spin_lock_irq(&fq->mq_flush_lock);
                list_move_tail(&rq->flush.list, &fq->flush_data_in_flight);
                spin_unlock_irq(&fq->mq_flush_lock);