2 files changed, 31 insertions, 10 deletions

diff --git a/net/sched/Kconfig b/net/sched/Kconfig
index 21f9c76..2f691fb 100644
--- a/net/sched/Kconfig
+++ b/net/sched/Kconfig
@@ -328,13 +328,16 @@ config NET_CLS_FLOW
 	  module will be called cls_flow.
 
 config NET_CLS_CGROUP
-	bool "Control Group Classifier"
+	tristate "Control Group Classifier"
 	select NET_CLS
 	depends on CGROUPS
 	---help---
 	  Say Y here if you want to classify packets based on the control
 	  cgroup of their process.
 
+	  To compile this code as a module, choose M here: the
+	  module will be called cls_cgroup.
+
 config NET_EMATCH
 	bool "Extended Matches"
 	select NET_CLS
diff --git a/net/sched/cls_cgroup.c b/net/sched/cls_cgroup.c
index e4877ca..7f27d2c 100644
--- a/net/sched/cls_cgroup.c
+++ b/net/sched/cls_cgroup.c
@@ -24,6 +24,25 @@ struct cgroup_cls_state
 	u32 classid;
 };
 
+static struct cgroup_subsys_state *cgrp_create(struct cgroup_subsys *ss,
+					       struct cgroup *cgrp);
+static void cgrp_destroy(struct cgroup_subsys *ss, struct cgroup *cgrp);
+static int cgrp_populate(struct cgroup_subsys *ss, struct cgroup *cgrp);
+
+struct cgroup_subsys net_cls_subsys = {
+	.name		= "net_cls",
+	.create		= cgrp_create,
+	.destroy	= cgrp_destroy,
+	.populate	= cgrp_populate,
+#ifdef CONFIG_NET_CLS_CGROUP
+	.subsys_id	= net_cls_subsys_id,
+#else
+#define net_cls_subsys_id net_cls_subsys.subsys_id
+#endif
+	.module		= THIS_MODULE,
+};
+
+
 static inline struct cgroup_cls_state *cgrp_cls_state(struct cgroup *cgrp)
 {
 	return container_of(cgroup_subsys_state(cgrp, net_cls_subsys_id),
@@ -79,14 +98,6 @@ static int cgrp_populate(struct cgroup_subsys *ss, struct cgroup *cgrp)
 	return cgroup_add_files(cgrp, ss, ss_files, ARRAY_SIZE(ss_files));
 }
 
-struct cgroup_subsys net_cls_subsys = {
-	.name		= "net_cls",
-	.create		= cgrp_create,
-	.destroy	= cgrp_destroy,
-	.populate	= cgrp_populate,
-	.subsys_id	= net_cls_subsys_id,
-};
-
 struct cls_cgroup_head
 {
 	u32			handle;
@@ -277,12 +288,19 @@ static struct tcf_proto_ops cls_cgroup_ops __read_mostly = {
 
 static int __init init_cgroup_cls(void)
 {
-	return register_tcf_proto_ops(&cls_cgroup_ops);
+	int ret = register_tcf_proto_ops(&cls_cgroup_ops);
+	if (ret)
+		return ret;
+	ret = cgroup_load_subsys(&net_cls_subsys);
+	if (ret)
+		unregister_tcf_proto_ops(&cls_cgroup_ops);
+	return ret;
 }
 
 static void __exit exit_cgroup_cls(void)
 {
 	unregister_tcf_proto_ops(&cls_cgroup_ops);
+	cgroup_unload_subsys(&net_cls_subsys);
 }
 
 module_init(init_cgroup_cls);