block: Initial support for data-less (or empty) barrier support

[mirror_ubuntu-bionic-kernel.git] / include / linux / blkdev.h

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 610967992ddb48c24635749cd66ded0c84eceea3..fb2ff749dc1f3edc2e5aaaaf0c7abf3dab807268 100644 (file)
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -540,6 +540,7 @@ enum {
 #define blk_barrier_rq(rq)     ((rq)->cmd_flags & REQ_HARDBARRIER)
 #define blk_fua_rq(rq)         ((rq)->cmd_flags & REQ_FUA)
 #define blk_bidi_rq(rq)                ((rq)->next_rq != NULL)
+#define blk_empty_barrier(rq)  (blk_barrier_rq(rq) && blk_fs_request(rq) && !(rq)->hard_nr_sectors)
 
 #define list_entry_rq(ptr)     list_entry((ptr), struct request, queuelist)