net_sched: add network namespace support for tc actions

Currently tc actions are stored in a per-module hashtable,
therefore are visible to all network namespaces. This is
probably the last part of the tc subsystem which is not
aware of netns now. This patch makes them per-netns,
several tc action API's need to be adjusted for this.

The tc action API code is ugly due to historical reasons,
we need to refactor that code in the future.

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

1 files changed, 47 insertions, 5 deletions

diff --git a/net/sched/act_bpf.c b/net/sched/act_bpf.c
index 0bc6f912f870..8c9f1f0459ab 100644
--- a/net/sched/act_bpf.c
+++ b/net/sched/act_bpf.c
@@ -33,6 +33,8 @@ struct tcf_bpf_cfg {
 	bool is_ebpf;
 };
 
+static int bpf_net_id;
+
 static int tcf_bpf(struct sk_buff *skb, const struct tc_action *act,
 		   struct tcf_result *res)
 {
@@ -275,6 +277,7 @@ static int tcf_bpf_init(struct net *net, struct nlattr *nla,
 			struct nlattr *est, struct tc_action *act,
 			int replace, int bind)
 {
+	struct tc_action_net *tn = net_generic(net, bpf_net_id);
 	struct nlattr *tb[TCA_ACT_BPF_MAX + 1];
 	struct tcf_bpf_cfg cfg, old;
 	struct tc_act_bpf *parm;
@@ -294,8 +297,8 @@ static int tcf_bpf_init(struct net *net, struct nlattr *nla,
 
 	parm = nla_data(tb[TCA_ACT_BPF_PARMS]);
 
-	if (!tcf_hash_check(parm->index, act, bind)) {
-		ret = tcf_hash_create(parm->index, est, act,
+	if (!tcf_hash_check(tn, parm->index, act, bind)) {
+		ret = tcf_hash_create(tn, parm->index, est, act,
 				      sizeof(*prog), bind, true);
 		if (ret < 0)
 			return ret;
@@ -344,7 +347,7 @@ static int tcf_bpf_init(struct net *net, struct nlattr *nla,
 	rcu_assign_pointer(prog->filter, cfg.filter);
 
 	if (res == ACT_P_CREATED) {
-		tcf_hash_insert(act);
+		tcf_hash_insert(tn, act);
 	} else {
 		/* make sure the program being replaced is no longer executing */
 		synchronize_rcu();
@@ -367,6 +370,22 @@ static void tcf_bpf_cleanup(struct tc_action *act, int bind)
 	tcf_bpf_cfg_cleanup(&tmp);
 }
 
+static int tcf_bpf_walker(struct net *net, struct sk_buff *skb,
+			  struct netlink_callback *cb, int type,
+			  struct tc_action *a)
+{
+	struct tc_action_net *tn = net_generic(net, bpf_net_id);
+
+	return tcf_generic_walker(tn, skb, cb, type, a);
+}
+
+static int tcf_bpf_search(struct net *net, struct tc_action *a, u32 index)
+{
+	struct tc_action_net *tn = net_generic(net, bpf_net_id);
+
+	return tcf_hash_search(tn, a, index);
+}
+
 static struct tc_action_ops act_bpf_ops __read_mostly = {
 	.kind		=	"bpf",
 	.type		=	TCA_ACT_BPF,
@@ -375,16 +394,39 @@ static struct tc_action_ops act_bpf_ops __read_mostly = {
 	.dump		=	tcf_bpf_dump,
 	.cleanup	=	tcf_bpf_cleanup,
 	.init		=	tcf_bpf_init,
+	.walk		=	tcf_bpf_walker,
+	.lookup		=	tcf_bpf_search,
+};
+
+static __net_init int bpf_init_net(struct net *net)
+{
+	struct tc_action_net *tn = net_generic(net, bpf_net_id);
+
+	return tc_action_net_init(tn, &act_bpf_ops, BPF_TAB_MASK);
+}
+
+static void __net_exit bpf_exit_net(struct net *net)
+{
+	struct tc_action_net *tn = net_generic(net, bpf_net_id);
+
+	tc_action_net_exit(tn);
+}
+
+static struct pernet_operations bpf_net_ops = {
+	.init = bpf_init_net,
+	.exit = bpf_exit_net,
+	.id   = &bpf_net_id,
+	.size = sizeof(struct tc_action_net),
 };
 
 static int __init bpf_init_module(void)
 {
-	return tcf_register_action(&act_bpf_ops, BPF_TAB_MASK);
+	return tcf_register_action(&act_bpf_ops, &bpf_net_ops);
 }
 
 static void __exit bpf_cleanup_module(void)
 {
-	tcf_unregister_action(&act_bpf_ops);
+	tcf_unregister_action(&act_bpf_ops, &bpf_net_ops);
 }
 
 module_init(bpf_init_module);