devcgroup: make a helper to convert cgroup_subsys_state to devs_cgroup

This is just picking the container_of out of cgroup_to_devcgroup into a
separate function.

This new css_to_devcgroup will be used in the 2nd patch.

Signed-off-by: Pavel Emelyanov <[email protected]>
Acked-by: Serge Hallyn <[email protected]>
Cc: Paul Menage <[email protected]>
Cc: Balbir Singh <[email protected]>
Cc: James Morris <[email protected]>
Cc: Chris Wright <[email protected]>
Cc: Stephen Smalley <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

diff --git a/security/device_cgroup.c b/security/device_cgroup.c
index 4ea583689eec0ae6cdb638d7ed025f25e9bac025..15f2f8003ba38844a5209d6e76cfe4a15dc28881 100644 (file)
--- a/security/device_cgroup.c
+++ b/security/device_cgroup.c
@@ -49,10 +49,14 @@ struct dev_cgroup {
        spinlock_t lock;
 };
 
+static inline struct dev_cgroup *css_to_devcgroup(struct cgroup_subsys_state *s)
+{
+       return container_of(s, struct dev_cgroup, css);
+}
+
 static inline struct dev_cgroup *cgroup_to_devcgroup(struct cgroup *cgroup)
 {
-       return container_of(cgroup_subsys_state(cgroup, devices_subsys_id),
-                           struct dev_cgroup, css);
+       return css_to_devcgroup(cgroup_subsys_state(cgroup, devices_subsys_id));
 }
 
 struct cgroup_subsys devices_subsys;