bfq-iosched: Ensure bio->bi_blkg is valid before using it

[linux-2.6-block.git] / block / bfq-cgroup.c

diff --git a/block/bfq-cgroup.c b/block/bfq-cgroup.c
index cea0ae12f93783df801a2b85fc2d73cbea994f3c..e1419edde2ec5473f8c7b6868056019cc6df4c2c 100644 (file)
--- a/block/bfq-cgroup.c
+++ b/block/bfq-cgroup.c
@@ -351,6 +351,9 @@ void bfqg_stats_update_legacy_io(struct request_queue *q, struct request *rq)
 {
        struct bfq_group *bfqg = blkg_to_bfqg(rq->bio->bi_blkg);
 
+       if (!bfqg)
+               return;
+
        blkg_rwstat_add(&bfqg->stats.bytes, rq->cmd_flags, blk_rq_bytes(rq));
        blkg_rwstat_add(&bfqg->stats.ios, rq->cmd_flags, 1);
 }