block: return just one value from part_in_flight

The previous patches deleted all the code that needed the second value
returned from part_in_flight - now the kernel only uses the first value.

Consequently, part_in_flight (and blk_mq_in_flight) may be changed so that
it only returns one value.

This patch just refactors the code, there's no functional change.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/block/blk-mq.c b/block/blk-mq.c
index b645275..9690f4f 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -100,25 +100,23 @@ static bool blk_mq_check_inflight(struct blk_mq_hw_ctx *hctx,
 	struct mq_inflight *mi = priv;
 
 	/*
-	 * index[0] counts the specific partition that was asked for. index[1]
-	 * counts the ones that are active on the whole device, so increment
-	 * that if mi->part is indeed a partition, and not a whole device.
+	 * index[0] counts the specific partition that was asked for.
 	 */
 	if (rq->part == mi->part)
 		mi->inflight[0]++;
-	if (mi->part->partno)
-		mi->inflight[1]++;
 
 	return true;
 }
 
-void blk_mq_in_flight(struct request_queue *q, struct hd_struct *part,
-		      unsigned int inflight[2])
+unsigned int blk_mq_in_flight(struct request_queue *q, struct hd_struct *part)
 {
+	unsigned inflight[2];
 	struct mq_inflight mi = { .part = part, .inflight = inflight, };
 
 	inflight[0] = inflight[1] = 0;
 	blk_mq_queue_tag_busy_iter(q, blk_mq_check_inflight, &mi);
+
+	return inflight[0];
 }
 
 static bool blk_mq_check_inflight_rw(struct blk_mq_hw_ctx *hctx,