commit 496d5e7560dbb84399dbd92316fc33857aa83900
author Tejun Heo <tj@kernel.org> Fri May 22 17:13:21 2015 -0400
committer Jens Axboe <axboe@fb.com> Tue Jun 02 08:33:33 2015 -0600
tree 1e60d21e0c680643251ee309382abd7d46d11e67
parent 56161634e4824380a67243a4cf3fa52eb1e5d836

blkcg: add blkcg_root_css

Add global constant blkcg_root_css which points to &blkcg_root.css.
This will be used by cgroup writeback support.  If blkcg is disabled,
it's defined as ERR_PTR(-EINVAL).

v2: The declarations moved to include/linux/blk-cgroup.h as suggested
    by Vivek.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jens Axboe <axboe@fb.com>