diff options
Diffstat (limited to 'block/bio.c')
| -rw-r--r-- | block/bio.c | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/block/bio.c b/block/bio.c index bfd41e8b53a8..748d7132f172 100644 --- a/block/bio.c +++ b/block/bio.c @@ -2029,6 +2029,41 @@ int bio_associate_blkg(struct bio *bio, struct blkcg_gq *blkg) } /** + * bio_associate_create_blkg - associate a bio with a blkg from q + * @q: request_queue where bio is going + * @bio: target bio + * + * Associate @bio with the blkg found from the bio's css and the request_queue. + * If one is not found, bio_lookup_blkg creates the blkg. + */ +int bio_associate_create_blkg(struct request_queue *q, struct bio *bio) +{ + struct blkcg *blkcg; + struct blkcg_gq *blkg; + int ret = 0; + + /* someone has already associated this bio with a blkg */ + if (bio->bi_blkg) + return ret; + + rcu_read_lock(); + + bio_associate_blkcg(bio, NULL); + blkcg = bio_blkcg(bio); + + if (!blkcg->css.parent) { + ret = bio_associate_blkg(bio, q->root_blkg); + } else { + blkg = blkg_lookup_create(blkcg, q); + + ret = bio_associate_blkg(bio, blkg); + } + + rcu_read_unlock(); + return ret; +} + +/** * bio_disassociate_task - undo bio_associate_current() * @bio: target bio */ @@ -2057,6 +2092,9 @@ void bio_clone_blkcg_association(struct bio *dst, struct bio *src) { if (src->bi_css) WARN_ON(bio_associate_blkcg(dst, src->bi_css)); + + if (src->bi_blkg) + bio_associate_blkg(dst, src->bi_blkg); } EXPORT_SYMBOL_GPL(bio_clone_blkcg_association); #endif /* CONFIG_BLK_CGROUP */ |