net_sched: move tc_action into tcf_common

struct tc_action is confusing, currently we use it for two purposes:
1) Pass in arguments and carry out results from helper functions
2) A generic representation for tc actions

The first one is error-prone, since we need to make sure we don't
miss anything. This patch aims to get rid of this use, by moving
tc_action into tcf_common, so that they are allocated together
in hashtable and can be cast'ed easily.

And together with the following patch, we could really make
tc_action a generic representation for all tc actions and each
type of action can inherit from it.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 26 insertions, 22 deletions

diff --git a/net/sched/act_ipt.c b/net/sched/act_ipt.c
index b8c50600697a..378c1c976058 100644
--- a/net/sched/act_ipt.c
+++ b/net/sched/act_ipt.c
@@ -31,8 +31,10 @@
 #define IPT_TAB_MASK     15
 
 static int ipt_net_id;
+static struct tc_action_ops act_ipt_ops;
 
 static int xt_net_id;
+static struct tc_action_ops act_xt_ops;
 
 static int ipt_init_target(struct xt_entry_target *t, char *table,
 			   unsigned int hook)
@@ -90,8 +92,8 @@ static const struct nla_policy ipt_policy[TCA_IPT_MAX + 1] = {
 };
 
 static int __tcf_ipt_init(struct tc_action_net *tn, struct nlattr *nla,
-			  struct nlattr *est, struct tc_action *a, int ovr,
-			  int bind)
+			  struct nlattr *est, struct tc_action **a,
+			  const struct tc_action_ops *ops, int ovr, int bind)
 {
 	struct nlattr *tb[TCA_IPT_MAX + 1];
 	struct tcf_ipt *ipt;
@@ -118,19 +120,19 @@ static int __tcf_ipt_init(struct tc_action_net *tn, struct nlattr *nla,
 
 	if (tb[TCA_IPT_HOOK] == NULL || tb[TCA_IPT_TARG] == NULL) {
 		if (exists)
-			tcf_hash_release(a, bind);
+			tcf_hash_release(*a, bind);
 		return -EINVAL;
 	}
 
 	td = (struct xt_entry_target *)nla_data(tb[TCA_IPT_TARG]);
 	if (nla_len(tb[TCA_IPT_TARG]) < td->u.target_size) {
 		if (exists)
-			tcf_hash_release(a, bind);
+			tcf_hash_release(*a, bind);
 		return -EINVAL;
 	}
 
 	if (!exists) {
-		ret = tcf_hash_create(tn, index, est, a, sizeof(*ipt), bind,
+		ret = tcf_hash_create(tn, index, est, a, ops, bind,
 				      false);
 		if (ret)
 			return ret;
@@ -138,13 +140,11 @@ static int __tcf_ipt_init(struct tc_action_net *tn, struct nlattr *nla,
 	} else {
 		if (bind)/* dont override defaults */
 			return 0;
-		tcf_hash_release(a, bind);
+		tcf_hash_release(*a, bind);
 
 		if (!ovr)
 			return -EEXIST;
 	}
-	ipt = to_ipt(a);
-
 	hook = nla_get_u32(tb[TCA_IPT_HOOK]);
 
 	err = -ENOMEM;
@@ -163,6 +163,8 @@ static int __tcf_ipt_init(struct tc_action_net *tn, struct nlattr *nla,
 	if (err < 0)
 		goto err3;
 
+	ipt = to_ipt(*a);
+
 	spin_lock_bh(&ipt->tcf_lock);
 	if (ret != ACT_P_CREATED) {
 		ipt_destroy_target(ipt->tcfi_t);
@@ -174,7 +176,7 @@ static int __tcf_ipt_init(struct tc_action_net *tn, struct nlattr *nla,
 	ipt->tcfi_hook  = hook;
 	spin_unlock_bh(&ipt->tcf_lock);
 	if (ret == ACT_P_CREATED)
-		tcf_hash_insert(tn, a);
+		tcf_hash_insert(tn, *a);
 	return ret;
 
 err3:
@@ -183,33 +185,33 @@ err2:
 	kfree(tname);
 err1:
 	if (ret == ACT_P_CREATED)
-		tcf_hash_cleanup(a, est);
+		tcf_hash_cleanup(*a, est);
 	return err;
 }
 
 static int tcf_ipt_init(struct net *net, struct nlattr *nla,
-			struct nlattr *est, struct tc_action *a, int ovr,
+			struct nlattr *est, struct tc_action **a, int ovr,
 			int bind)
 {
 	struct tc_action_net *tn = net_generic(net, ipt_net_id);
 
-	return __tcf_ipt_init(tn, nla, est, a, ovr, bind);
+	return __tcf_ipt_init(tn, nla, est, a, &act_ipt_ops, ovr, bind);
 }
 
 static int tcf_xt_init(struct net *net, struct nlattr *nla,
-		       struct nlattr *est, struct tc_action *a, int ovr,
+		       struct nlattr *est, struct tc_action **a, int ovr,
 		       int bind)
 {
 	struct tc_action_net *tn = net_generic(net, xt_net_id);
 
-	return __tcf_ipt_init(tn, nla, est, a, ovr, bind);
+	return __tcf_ipt_init(tn, nla, est, a, &act_xt_ops, ovr, bind);
 }
 
 static int tcf_ipt(struct sk_buff *skb, const struct tc_action *a,
 		   struct tcf_result *res)
 {
 	int ret = 0, result = 0;
-	struct tcf_ipt *ipt = a->priv;
+	struct tcf_ipt *ipt = to_ipt(a);
 	struct xt_action_param par;
 
 	if (skb_unclone(skb, GFP_ATOMIC))
@@ -259,7 +261,7 @@ static int tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind,
 			int ref)
 {
 	unsigned char *b = skb_tail_pointer(skb);
-	struct tcf_ipt *ipt = a->priv;
+	struct tcf_ipt *ipt = to_ipt(a);
 	struct xt_entry_target *t;
 	struct tcf_t tm;
 	struct tc_cnt c;
@@ -299,14 +301,14 @@ nla_put_failure:
 
 static int tcf_ipt_walker(struct net *net, struct sk_buff *skb,
 			  struct netlink_callback *cb, int type,
-			  struct tc_action *a)
+			  const struct tc_action_ops *ops)
 {
 	struct tc_action_net *tn = net_generic(net, ipt_net_id);
 
-	return tcf_generic_walker(tn, skb, cb, type, a);
+	return tcf_generic_walker(tn, skb, cb, type, ops);
 }
 
-static int tcf_ipt_search(struct net *net, struct tc_action *a, u32 index)
+static int tcf_ipt_search(struct net *net, struct tc_action **a, u32 index)
 {
 	struct tc_action_net *tn = net_generic(net, ipt_net_id);
 
@@ -323,6 +325,7 @@ static struct tc_action_ops act_ipt_ops = {
 	.init		=	tcf_ipt_init,
 	.walk		=	tcf_ipt_walker,
 	.lookup		=	tcf_ipt_search,
+	.size		=	sizeof(struct tcf_ipt),
 };
 
 static __net_init int ipt_init_net(struct net *net)
@@ -348,14 +351,14 @@ static struct pernet_operations ipt_net_ops = {
 
 static int tcf_xt_walker(struct net *net, struct sk_buff *skb,
 			 struct netlink_callback *cb, int type,
-			 struct tc_action *a)
+			 const struct tc_action_ops *ops)
 {
 	struct tc_action_net *tn = net_generic(net, xt_net_id);
 
-	return tcf_generic_walker(tn, skb, cb, type, a);
+	return tcf_generic_walker(tn, skb, cb, type, ops);
 }
 
-static int tcf_xt_search(struct net *net, struct tc_action *a, u32 index)
+static int tcf_xt_search(struct net *net, struct tc_action **a, u32 index)
 {
 	struct tc_action_net *tn = net_generic(net, xt_net_id);
 
@@ -372,6 +375,7 @@ static struct tc_action_ops act_xt_ops = {
 	.init		=	tcf_xt_init,
 	.walk		=	tcf_xt_walker,
 	.lookup		=	tcf_xt_search,
+	.size		=	sizeof(struct tcf_ipt),
 };
 
 static __net_init int xt_init_net(struct net *net)