diff options
Diffstat (limited to 'block')
| -rw-r--r-- | block/blk-cgroup.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 9a1c5839dd46..ebff1af402e5 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -633,6 +633,14 @@ int blkg_conf_prep(struct blkcg *blkcg, const struct blkcg_policy *pol, q = bdev->bd_disk->queue; + /* + * blkcg_deactivate_policy() requires queue to be frozen, we can grab + * q_usage_counter to prevent concurrent with blkcg_deactivate_policy(). + */ + ret = blk_queue_enter(q, 0); + if (ret) + return ret; + rcu_read_lock(); spin_lock_irq(&q->queue_lock); @@ -702,6 +710,7 @@ int blkg_conf_prep(struct blkcg *blkcg, const struct blkcg_policy *pol, goto success; } success: + blk_queue_exit(q); ctx->bdev = bdev; ctx->blkg = blkg; ctx->body = input; @@ -714,6 +723,7 @@ fail_unlock: rcu_read_unlock(); fail: blkdev_put_no_open(bdev); + blk_queue_exit(q); /* * If queue was bypassing, we should retry. Do so after a * short msleep(). It isn't strictly necessary but queue |