blkcg: make blkg_conf_prep() take @pol and return with queue lock held

Add @pol to blkg_conf_prep() and let it return with queue lock held
(to be released by blkg_conf_finish()).  Note that @pol isn't used
yet.

This is to prepare for per-queue policy activation and doesn't cause
any visible difference.

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

1 files changed, 2 insertions, 1 deletions

diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h
index be80d6eb6531..df1c7b290c22 100644
--- a/block/blk-cgroup.h
+++ b/block/blk-cgroup.h
@@ -128,7 +128,8 @@ struct blkg_conf_ctx {
         u64                     v;
 };
 
-int blkg_conf_prep(struct blkio_cgroup *blkcg, const char *input,
+int blkg_conf_prep(struct blkio_cgroup *blkcg,
+                   const struct blkio_policy_type *pol, const char *input,
                    struct blkg_conf_ctx *ctx);
 void blkg_conf_finish(struct blkg_conf_ctx *ctx);