[NETNS][FRAGS]: Make the pernet subsystem for fragments.

On namespace start we mainly prepare the ctl variables.

When the namespace is stopped we have to kill all the fragments that
point to this namespace.  The inet_frags_exit_net() handles it.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 33 insertions, 2 deletions

diff --git a/include/net/inet_frag.h b/include/net/inet_frag.h
index 3695ff4..7374251 100644
--- a/include/net/inet_frag.h
+++ b/include/net/inet_frag.h
@@ -54,6 +54,7 @@ void inet_frags_init(struct inet_frags *);
 void inet_frags_fini(struct inet_frags *);
 
 void inet_frags_init_net(struct netns_frags *nf);
+void inet_frags_exit_net(struct netns_frags *nf, struct inet_frags *f);
 
 void inet_frag_kill(struct inet_frag_queue *q, struct inet_frags *f);
 void inet_frag_destroy(struct inet_frag_queue *q,
diff --git a/net/ipv4/inet_fragment.c b/net/ipv4/inet_fragment.c
index f1b95e1..724d69a 100644
--- a/net/ipv4/inet_fragment.c
+++ b/net/ipv4/inet_fragment.c
@@ -83,6 +83,13 @@ void inet_frags_fini(struct inet_frags *f)
 }
 EXPORT_SYMBOL(inet_frags_fini);
 
+void inet_frags_exit_net(struct netns_frags *nf, struct inet_frags *f)
+{
+	nf->low_thresh = 0;
+	inet_frag_evictor(nf, f);
+}
+EXPORT_SYMBOL(inet_frags_exit_net);
+
 static inline void fq_unlink(struct inet_frag_queue *fq, struct inet_frags *f)
 {
 	write_lock(&f->lock);
diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c
index 29b4b09..a2e92f9 100644
--- a/net/ipv4/ip_fragment.c
+++ b/net/ipv4/ip_fragment.c
@@ -713,9 +713,20 @@ static int ipv4_frags_init_net(struct net *net)
 	return ip4_frags_ctl_register(net);
 }
 
+static void ipv4_frags_exit_net(struct net *net)
+{
+	ip4_frags_ctl_unregister(net);
+	inet_frags_exit_net(&net->ipv4.frags, &ip4_frags);
+}
+
+static struct pernet_operations ip4_frags_ops = {
+	.init = ipv4_frags_init_net,
+	.exit = ipv4_frags_exit_net,
+};
+
 void __init ipfrag_init(void)
 {
-	ipv4_frags_init_net(&init_net);
+	register_pernet_subsys(&ip4_frags_ops);
 	ip4_frags.hashfn = ip4_hashfn;
 	ip4_frags.constructor = ip4_frag_init;
 	ip4_frags.destructor = ip4_frag_free;
diff --git a/net/ipv6/reassembly.c b/net/ipv6/reassembly.c
index 0c4bc46..f936d04 100644
--- a/net/ipv6/reassembly.c
+++ b/net/ipv6/reassembly.c
@@ -728,6 +728,17 @@ static int ipv6_frags_init_net(struct net *net)
 	return ip6_frags_sysctl_register(net);
 }
 
+static void ipv6_frags_exit_net(struct net *net)
+{
+	ip6_frags_sysctl_unregister(net);
+	inet_frags_exit_net(&net->ipv6.frags, &ip6_frags);
+}
+
+static struct pernet_operations ip6_frags_ops = {
+	.init = ipv6_frags_init_net,
+	.exit = ipv6_frags_exit_net,
+};
+
 int __init ipv6_frag_init(void)
 {
 	int ret;
@@ -736,7 +747,7 @@ int __init ipv6_frag_init(void)
 	if (ret)
 		goto out;
 
-	ipv6_frags_init_net(&init_net);
+	register_pernet_subsys(&ip6_frags_ops);
 
 	ip6_frags.hashfn = ip6_hashfn;
 	ip6_frags.constructor = ip6_frag_init;
@@ -754,5 +765,6 @@ out:
 void ipv6_frag_exit(void)
 {
 	inet_frags_fini(&ip6_frags);
+	unregister_pernet_subsys(&ip6_frags_ops);
 	inet6_del_protocol(&frag_protocol, IPPROTO_FRAGMENT);
 }