[PKT_ACT]: Fixup tcf_result updating wrt. tcf_action_exec() calls.

- Pass tcf_result into tcf_action_exec()
- Update res->classid and res->class on non-zero
  skb->tc_classid, then reset skb->tc_classid
- Update tcf_action_exec() callers in cls_u32.c
  and cls_fw.c

Based upon a patch by Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/pkt_sched.h

@@ -376,7 +376,7 @@ struct tc_action_ops
 extern int tcf_register_action(struct tc_action_ops *a);
 extern int tcf_unregister_action(struct tc_action_ops *a);
 extern void tcf_action_destroy(struct tc_action *a, int bind);
-extern int tcf_action_exec(struct sk_buff *skb, struct tc_action *a);
+extern int tcf_action_exec(struct sk_buff *skb, struct tc_action *a, struct tcf_result *res);
 extern int tcf_action_init(struct rtattr *rta, struct rtattr *est, struct tc_action *a,char *n, int ovr, int bind);
 extern int tcf_action_init_1(struct rtattr *rta, struct rtattr *est, struct tc_action *a,char *n, int ovr, int bind);
 extern int tcf_action_dump(struct sk_buff *skb, struct tc_action *a, int, int);

net/sched/act_api.c

@@ -155,7 +155,7 @@ struct tc_action_ops *tc_lookup_action_id(u32 type)
 	return a;
 }
 
-int tcf_action_exec(struct sk_buff *skb,struct tc_action *act)
+int tcf_action_exec(struct sk_buff *skb,struct tc_action *act, struct tcf_result *res)
 {
 
 	struct tc_action *a;
@@ -164,7 +164,8 @@ int tcf_action_exec(struct sk_buff *skb,struct tc_action *act)
 	if (skb->tc_verd & TC_NCLS) {
 		skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
 		D2PRINTK("(%p)tcf_action_exec: cleared TC_NCLS in %s out %s\n",skb,skb->input_dev?skb->input_dev->name:"xxx",skb->dev->name);
-		return TC_ACT_OK;
+		ret = TC_ACT_OK;
+		goto exec_done;
 	}
 	while ((a = act) != NULL) {
 repeat:
@@ -186,6 +187,11 @@ int tcf_action_exec(struct sk_buff *skb,struct tc_action *act)
 	}
 
 exec_done:
+	if (skb->tc_classid > 0) {
+		res->classid = skb->tc_classid;
+		res->class = 0;
+		skb->tc_classid = 0;
+	}
 
 	return ret;
 }

net/sched/cls_fw.c

@@ -102,7 +102,7 @@ static int fw_classify(struct sk_buff *skb, struct tcf_proto *tp,
 			}
 #endif
                                if (f->action) {
-                                       int pol_res = tcf_action_exec(skb, f->action);
+                                       int pol_res = tcf_action_exec(skb, f->action, res);
                                        if (pol_res >= 0)
                                                return pol_res;
                                } else

net/sched/cls_u32.c

@@ -175,12 +175,7 @@ static int u32_classify(struct sk_buff *skb, struct tcf_proto *tp, struct tcf_re
 #endif
 #ifdef CONFIG_NET_CLS_ACT
 				if (n->action) {
-					int pol_res = tcf_action_exec(skb, n->action);
-					if (skb->tc_classid > 0) {
-						res->classid = skb->tc_classid;
-						skb->tc_classid = 0;
-					}
-
+					int pol_res = tcf_action_exec(skb, n->action, res);
 					if (pol_res >= 0)
 						return pol_res;
 				} else