block: set REQ_TYPE_FS on flush requests

the block layer doesn't set rq->cmd_type on flush requests. By
definition, it should be REQ_TYPE_FS (the lower layers build a command
and interpret the result of it, that is, the block layer doesn't know
the details).

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
diff --git a/block/blk-barrier.c b/block/blk-barrier.c
index 557f693..d95a144 100644
--- a/block/blk-barrier.c
+++ b/block/blk-barrier.c
@@ -134,6 +134,7 @@
 	}
 
 	blk_rq_init(q, rq);
+	rq->cmd_type = REQ_TYPE_FS;
 	rq->cmd_flags = REQ_HARDBARRIER | REQ_FLUSH;
 	rq->rq_disk = q->bar_rq.rq_disk;
 	rq->end_io = end_io;