diff options
Diffstat (limited to 'block/blk-cgroup.c')
| -rw-r--r-- | block/blk-cgroup.c | 18 |
1 files changed, 17 insertions, 1 deletions
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index bb52797c02bd..8e32cc494808 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -156,6 +156,22 @@ static void blkg_async_bio_workfn(struct work_struct *work) } /** + * bio_blkcg_css - return the blkcg CSS associated with a bio + * @bio: target bio + * + * This returns the CSS for the blkcg associated with a bio, or %NULL if not + * associated. Callers are expected to either handle %NULL or know association + * has been done prior to calling this. + */ +struct cgroup_subsys_state *bio_blkcg_css(struct bio *bio) +{ + if (!bio || !bio->bi_blkg) + return NULL; + return &bio->bi_blkg->blkcg->css; +} +EXPORT_SYMBOL_GPL(bio_blkcg_css); + +/** * blkcg_parent - get the parent of a blkcg * @blkcg: blkcg of interest * @@ -1938,7 +1954,7 @@ void bio_associate_blkg(struct bio *bio) rcu_read_lock(); if (bio->bi_blkg) - css = &bio_blkcg(bio)->css; + css = bio_blkcg_css(bio); else css = blkcg_css(); |