[PATCH] block: set rq->cmd_flags with bio->opf instead of data->cmd_flags when bio is not Null

[chenxiang]

In function blk_mq_make_request(), though data->cmd_flags will be
initialized with bio->opf, later bio->opf may be set as REQ_INTEGRITY
if enabled DIX. So need to use bio->opf instead of data->cmd_flags in
function blk_mq_rq_ctx_init(), or  flags REQ_INTEGRITY will not be set
for rq->cmd_flags. It will cause dix=0 in function
sd_setup_read_write_cmnd() when enabled DIX, which will cause IO 
exception when enabled DIX.

For some IOs such as internal IO from SCSI layer, the parameter bio of
function blk_mq_get_request() is Null, so need to check bio to
decise rq->cmd_flags.

Fixes: f9afca4d367b ("blk-mq: pass in request/bio flags to queue mapping")

Signed-off-by: Xiang Chen <chenxiang66@xxxxxxxxxxxxx>
Reviewed-by: John Garry <john.garry@xxxxxxxxxx>
---
 block/blk-mq.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 3ba37b9..c4a1c63 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -394,7 +394,7 @@ static struct request *blk_mq_get_request(struct request_queue *q,
 		return NULL;
 	}
 
-	rq = blk_mq_rq_ctx_init(data, tag, data->cmd_flags);
+	rq = blk_mq_rq_ctx_init(data, tag, bio ? bio->bi_opf : data->cmd_flags);
 	if (!op_is_flush(data->cmd_flags)) {
 		rq->elv.icq = NULL;
 		if (e && e->type->ops.prepare_request) {
-- 
2.8.1