cgroup: remove css_parent()
cgroup in general is moving towards using cgroup_subsys_state as the
fundamental structural component and css_parent() was introduced to
convert from using cgroup->parent to css->parent. It was quite some
time ago and we're moving forward with making css more prominent.
This patch drops the trivial wrapper css_parent() and let the users
dereference css->parent. While at it, explicitly mark fields of css
which are public and immutable.
v2: New usage from device_cgroup.c converted.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: "David S. Miller" <davem@davemloft.net>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Johannes Weiner <hannes@cmpxchg.org>
diff --git a/security/device_cgroup.c b/security/device_cgroup.c
index 7dbac40..ce14a31 100644
--- a/security/device_cgroup.c
+++ b/security/device_cgroup.c
@@ -182,7 +182,7 @@
static int devcgroup_online(struct cgroup_subsys_state *css)
{
struct dev_cgroup *dev_cgroup = css_to_devcgroup(css);
- struct dev_cgroup *parent_dev_cgroup = css_to_devcgroup(css_parent(css));
+ struct dev_cgroup *parent_dev_cgroup = css_to_devcgroup(css->parent);
int ret = 0;
mutex_lock(&devcgroup_mutex);
@@ -455,7 +455,7 @@
static int parent_has_perm(struct dev_cgroup *childcg,
struct dev_exception_item *ex)
{
- struct dev_cgroup *parent = css_to_devcgroup(css_parent(&childcg->css));
+ struct dev_cgroup *parent = css_to_devcgroup(childcg->css.parent);
if (!parent)
return 1;
@@ -476,7 +476,7 @@
static bool parent_allows_removal(struct dev_cgroup *childcg,
struct dev_exception_item *ex)
{
- struct dev_cgroup *parent = css_to_devcgroup(css_parent(&childcg->css));
+ struct dev_cgroup *parent = css_to_devcgroup(childcg->css.parent);
if (!parent)
return true;
@@ -614,7 +614,7 @@
char temp[12]; /* 11 + 1 characters needed for a u32 */
int count, rc = 0;
struct dev_exception_item ex;
- struct dev_cgroup *parent = css_to_devcgroup(css_parent(&devcgroup->css));
+ struct dev_cgroup *parent = css_to_devcgroup(devcgroup->css.parent);
if (!capable(CAP_SYS_ADMIN))
return -EPERM;