block, drivers, cgroup: use op_is_write helper instead of checking for REQ_WRITE

We currently set REQ_WRITE/WRITE for all non READ IOs
like discard, flush, writesame, etc. In the next patches where we
no longer set up the op as a bitmap, we will not be able to
detect a operation direction like writesame by testing if REQ_WRITE is
set.

This patch converts the drivers and cgroup to use the
op_is_write helper. This should just cover the simple
cases. I did dm, md and bcache in their own patches
because they were more involved.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index bfec66fb26e2..4c6eb22cc85d 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -1190,7 +1190,7 @@ static int atapi_drain_needed(struct request *rq)
         if (likely(rq->cmd_type != REQ_TYPE_BLOCK_PC))
                 return 0;
 
-        if (!blk_rq_bytes(rq) || (rq->cmd_flags & REQ_WRITE))
+        if (!blk_rq_bytes(rq) || op_is_write(req_op(rq)))
                 return 0;
 
         return atapi_cmd_type(rq->cmd[0]) == ATAPI_MISC;