From fd42df305f804ddc0d5ac028e944784283b2f92d Mon Sep 17 00:00:00 2001 From: Dennis Zhou Date: Wed, 5 Dec 2018 12:10:34 -0500 Subject: blkcg: associate writeback bios with a blkg One of the goals of this series is to remove a separate reference to the css of the bio. This can and should be accessed via bio_blkcg(). In this patch, wbc_init_bio() now requires a bio to have a device associated with it. Signed-off-by: Dennis Zhou Reviewed-by: Josef Bacik Acked-by: Tejun Heo Signed-off-by: Jens Axboe --- block/bio.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'block') diff --git a/block/bio.c b/block/bio.c index f0f069c1823c..b42477b6a225 100644 --- a/block/bio.c +++ b/block/bio.c @@ -2034,6 +2034,24 @@ static void __bio_associate_blkg_from_css(struct bio *bio, rcu_read_unlock(); } +/** + * bio_associate_blkg_from_css - associate a bio with a specified css + * @bio: target bio + * @css: target css + * + * Associate @bio with the blkg found by combining the css's blkg and the + * request_queue of the @bio. This takes a reference on the css that will + * be put upon freeing of @bio. + */ +void bio_associate_blkg_from_css(struct bio *bio, + struct cgroup_subsys_state *css) +{ + css_get(css); + bio->bi_css = css; + __bio_associate_blkg_from_css(bio, css); +} +EXPORT_SYMBOL_GPL(bio_associate_blkg_from_css); + #ifdef CONFIG_MEMCG /** * bio_associate_blkg_from_page - associate a bio with the page's blkg -- cgit v1.2.1