[net-next,v3,10/10] net: sched: add termination action to allow goto chain

diff --git a/include/net/act_api.h b/include/net/act_api.h
index b22c6f3..26ffd83 100644
--- a/include/net/act_api.h
+++ b/include/net/act_api.h
@@ -42,6 +42,7 @@  struct tc_action {
 	struct gnet_stats_basic_cpu __percpu *cpu_bstats;
 	struct gnet_stats_queue __percpu *cpu_qstats;
 	struct tc_cookie	*act_cookie;
+	struct tcf_chain	*goto_chain;
 };
 #define tcf_head	common.tcfa_head
 #define tcf_index	common.tcfa_index
diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index 569b565..3688501 100644
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -193,8 +193,13 @@  struct Qdisc_ops {
 
 
 struct tcf_result {
-	unsigned long	class;
-	u32		classid;
+	union {
+		struct {
+			unsigned long	class;
+			u32		classid;
+		};
+		const struct tcf_proto *goto_tp;
+	};
 };
 
 struct tcf_proto_ops {
diff --git a/include/uapi/linux/pkt_cls.h b/include/uapi/linux/pkt_cls.h
index d613be3..1b9aa9e 100644
--- a/include/uapi/linux/pkt_cls.h
+++ b/include/uapi/linux/pkt_cls.h
@@ -51,6 +51,7 @@  enum {
 	(((combined) & (~TC_ACT_EXT_VAL_MASK)) == opcode)
 
 #define TC_ACT_JUMP __TC_ACT_EXT(1)
+#define TC_ACT_GOTO_CHAIN __TC_ACT_EXT(2)
 
 /* Action type identifiers*/
 enum {
diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index e389eb4..0ecf2a8 100644
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -28,6 +28,31 @@ 
 #include <net/act_api.h>
 #include <net/netlink.h>
 
+static int tcf_action_goto_chain_init(struct tc_action *a, struct tcf_proto *tp)
+{
+	u32 chain_index = a->tcfa_action & TC_ACT_EXT_VAL_MASK;
+
+	if (!tp)
+		return -EINVAL;
+	a->goto_chain = tcf_chain_get(tp->chain->block, chain_index);
+	if (!a->goto_chain)
+		return -ENOMEM;
+	return 0;
+}
+
+static void tcf_action_goto_chain_fini(struct tc_action *a)
+{
+	tcf_chain_put(a->goto_chain);
+}
+
+static void tcf_action_goto_chain_exec(const struct tc_action *a,
+				       struct tcf_result *res)
+{
+	const struct tcf_chain *chain = a->goto_chain;
+
+	res->goto_tp = rcu_dereference_bh(chain->filter_chain);
+}
+
 static void free_tcf(struct rcu_head *head)
 {
 	struct tc_action *p = container_of(head, struct tc_action, tcfa_rcu);
@@ -39,6 +64,8 @@  static void free_tcf(struct rcu_head *head)
 		kfree(p->act_cookie->data);
 		kfree(p->act_cookie);
 	}
+	if (p->goto_chain)
+		tcf_action_goto_chain_fini(p);
 
 	kfree(p);
 }
@@ -465,6 +492,8 @@  int tcf_action_exec(struct sk_buff *skb, struct tc_action **actions,
 				else /* faulty graph, stop pipeline */
 					return TC_ACT_OK;
 			}
+		} else if (TC_ACT_EXT_CMP(ret, TC_ACT_GOTO_CHAIN)) {
+			tcf_action_goto_chain_exec(a, res);
 		}
 
 		if (ret != TC_ACT_PIPE)
@@ -657,6 +686,17 @@  struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
 	if (err != ACT_P_CREATED)
 		module_put(a_o->owner);
 
+	if (TC_ACT_EXT_CMP(a->tcfa_action, TC_ACT_GOTO_CHAIN)) {
+		err = tcf_action_goto_chain_init(a, tp);
+		if (err) {
+			LIST_HEAD(actions);
+
+			list_add_tail(&a->list, &actions);
+			tcf_action_destroy(&actions, bind);
+			return ERR_PTR(err);
+		}
+	}
+
 	return a;
 
 err_mod:
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index 1112a2b..f8f2ca6 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -304,10 +304,14 @@  int tcf_classify(struct sk_buff *skb, const struct tcf_proto *tp,
 			continue;
 
 		err = tp->classify(skb, tp, res);
-		if (unlikely(err == TC_ACT_RECLASSIFY && !compat_mode))
+		if (unlikely(err == TC_ACT_RECLASSIFY && !compat_mode)) {
 			goto reset;
-		if (err >= 0)
+		} else if (unlikely(TC_ACT_EXT_CMP(err, TC_ACT_GOTO_CHAIN))) {
+			old_tp = res->goto_tp;
+			goto reset;
+		} else if (err >= 0) {
 			return err;
+		}
 	}
 
 	return TC_ACT_UNSPEC; /* signal: continue lookup */