diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h
index 1b5b2fe..33a0043 100644
--- a/include/linux/cgroup.h
+++ b/include/linux/cgroup.h
@@ -188,6 +188,15 @@
 	struct list_head cset_links;
 
 	/*
+	 * On the default hierarchy, a css_set for a cgroup with some
+	 * susbsys disabled will point to css's which are associated with
+	 * the closest ancestor which has the subsys enabled.  The
+	 * following lists all css_sets which point to this cgroup's css
+	 * for the given subsystem.
+	 */
+	struct list_head e_csets[CGROUP_SUBSYS_COUNT];
+
+	/*
 	 * Linked list running through all cgroups that can
 	 * potentially be reaped by the release agent. Protected by
 	 * release_list_lock
@@ -369,6 +378,15 @@
 	struct cgroup *mg_src_cgrp;
 	struct css_set *mg_dst_cset;
 
+	/*
+	 * On the default hierarhcy, ->subsys[ssid] may point to a css
+	 * attached to an ancestor instead of the cgroup this css_set is
+	 * associated with.  The following node is anchored at
+	 * ->subsys[ssid]->cgroup->e_csets[ssid] and provides a way to
+	 * iterate through all css's attached to a given cgroup.
+	 */
+	struct list_head e_cset_node[CGROUP_SUBSYS_COUNT];
+
 	/* For RCU-protected deletion */
 	struct rcu_head rcu_head;
 };