bsg: update check for rq based driver for blk-mq

bsg currently checks ->request_fn to check whether a queue can
handle struct request. But with blk-mq, we don't have a request_fn
yet are request based. Add a queue_is_rq_based() helper and use
that in bsg, I'm guessing this is not the last place we need to
update for this. Besides, it better explains what is being
checked.

Signed-off-by: Jens Axboe <axboe@fb.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/block/bsg.c b/block/bsg.c
index 420a5a9f1b23..e5214c148096 100644
--- a/block/bsg.c
+++ b/block/bsg.c
@@ -1008,7 +1008,7 @@ int bsg_register_queue(struct request_queue *q, struct device *parent,
         /*
          * we need a proper transport to send commands, not a stacked device
          */
-        if (!q->request_fn)
+        if (!queue_is_rq_based(q))
                 return 0;
 
         bcd = &q->bsg_dev;