IPVS: init and cleanup restructuring

DESCRIPTION
This patch tries to restore the initial init and cleanup
sequences that was before namspace patch.
Netns also requires action when net devices unregister
which has never been implemented. I.e this patch also
covers when a device moves into a network namespace,
and has to be released.

IMPLEMENTATION
The number of calls to register_pernet_device have been
reduced to one for the ip_vs.ko
Schedulers still have their own calls.

This patch adds a function __ip_vs_service_cleanup()
and an enable flag for the netfilter hooks.

The nf hooks will be enabled when the first service is loaded
and never disabled again, except when a namespace exit starts.

Signed-off-by: Hans Schillstrom <hans@schillstrom.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
[horms@verge.net.au: minor edit to changelog]
Signed-off-by: Simon Horman <horms@verge.net.au>

1 files changed, 92 insertions, 9 deletions

diff --git a/net/netfilter/ipvs/ip_vs_core.c b/net/netfilter/ipvs/ip_vs_core.c
index a0791dc05a2..a74dae6c5db 100644
--- a/net/netfilter/ipvs/ip_vs_core.c
+++ b/net/netfilter/ipvs/ip_vs_core.c
@@ -1113,6 +1113,9 @@ ip_vs_out(unsigned int hooknum, struct sk_buff *skb, int af)
 		return NF_ACCEPT;
 
 	net = skb_net(skb);
+	if (!net_ipvs(net)->enable)
+		return NF_ACCEPT;
+
 	ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
 #ifdef CONFIG_IP_VS_IPV6
 	if (af == AF_INET6) {
@@ -1343,6 +1346,7 @@ ip_vs_in_icmp(struct sk_buff *skb, int *related, unsigned int hooknum)
 		return NF_ACCEPT; /* The packet looks wrong, ignore */
 
 	net = skb_net(skb);
+
 	pd = ip_vs_proto_data_get(net, cih->protocol);
 	if (!pd)
 		return NF_ACCEPT;
@@ -1529,6 +1533,11 @@ ip_vs_in(unsigned int hooknum, struct sk_buff *skb, int af)
 			      IP_VS_DBG_ADDR(af, &iph.daddr), hooknum);
 		return NF_ACCEPT;
 	}
+	/* ipvs enabled in this netns ? */
+	net = skb_net(skb);
+	if (!net_ipvs(net)->enable)
+		return NF_ACCEPT;
+
 	ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
 
 	/* Bad... Do not break raw sockets */
@@ -1562,7 +1571,6 @@ ip_vs_in(unsigned int hooknum, struct sk_buff *skb, int af)
 			ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
 		}
 
-	net = skb_net(skb);
 	/* Protocol supported? */
 	pd = ip_vs_proto_data_get(net, iph.protocol);
 	if (unlikely(!pd))
@@ -1588,7 +1596,6 @@ ip_vs_in(unsigned int hooknum, struct sk_buff *skb, int af)
 	}
 
 	IP_VS_DBG_PKT(11, af, pp, skb, 0, "Incoming packet");
-	net = skb_net(skb);
 	ipvs = net_ipvs(net);
 	/* Check the server status */
 	if (cp->dest && !(cp->dest->flags & IP_VS_DEST_F_AVAILABLE)) {
@@ -1743,10 +1750,16 @@ ip_vs_forward_icmp(unsigned int hooknum, struct sk_buff *skb,
 		   int (*okfn)(struct sk_buff *))
 {
 	int r;
+	struct net *net;
 
 	if (ip_hdr(skb)->protocol != IPPROTO_ICMP)
 		return NF_ACCEPT;
 
+	/* ipvs enabled in this netns ? */
+	net = skb_net(skb);
+	if (!net_ipvs(net)->enable)
+		return NF_ACCEPT;
+
 	return ip_vs_in_icmp(skb, &r, hooknum);
 }
 
@@ -1757,10 +1770,16 @@ ip_vs_forward_icmp_v6(unsigned int hooknum, struct sk_buff *skb,
 		      int (*okfn)(struct sk_buff *))
 {
 	int r;
+	struct net *net;
 
 	if (ipv6_hdr(skb)->nexthdr != IPPROTO_ICMPV6)
 		return NF_ACCEPT;
 
+	/* ipvs enabled in this netns ? */
+	net = skb_net(skb);
+	if (!net_ipvs(net)->enable)
+		return NF_ACCEPT;
+
 	return ip_vs_in_icmp_v6(skb, &r, hooknum);
 }
 #endif
@@ -1884,21 +1903,72 @@ static int __net_init __ip_vs_init(struct net *net)
 		pr_err("%s(): no memory.\n", __func__);
 		return -ENOMEM;
 	}
+	/* Hold the beast until a service is registerd */
+	ipvs->enable = 0;
 	ipvs->net = net;
 	/* Counters used for creating unique names */
 	ipvs->gen = atomic_read(&ipvs_netns_cnt);
 	atomic_inc(&ipvs_netns_cnt);
 	net->ipvs = ipvs;
+
+	if (__ip_vs_estimator_init(net) < 0)
+		goto estimator_fail;
+
+	if (__ip_vs_control_init(net) < 0)
+		goto control_fail;
+
+	if (__ip_vs_protocol_init(net) < 0)
+		goto protocol_fail;
+
+	if (__ip_vs_app_init(net) < 0)
+		goto app_fail;
+
+	if (__ip_vs_conn_init(net) < 0)
+		goto conn_fail;
+
+	if (__ip_vs_sync_init(net) < 0)
+		goto sync_fail;
+
 	printk(KERN_INFO "IPVS: Creating netns size=%zu id=%d\n",
 			 sizeof(struct netns_ipvs), ipvs->gen);
 	return 0;
+/*
+ * Error handling
+ */
+
+sync_fail:
+	__ip_vs_conn_cleanup(net);
+conn_fail:
+	__ip_vs_app_cleanup(net);
+app_fail:
+	__ip_vs_protocol_cleanup(net);
+protocol_fail:
+	__ip_vs_control_cleanup(net);
+control_fail:
+	__ip_vs_estimator_cleanup(net);
+estimator_fail:
+	return -ENOMEM;
 }
 
 static void __net_exit __ip_vs_cleanup(struct net *net)
 {
+	__ip_vs_service_cleanup(net);	/* ip_vs_flush() with locks */
+	__ip_vs_conn_cleanup(net);
+	__ip_vs_app_cleanup(net);
+	__ip_vs_protocol_cleanup(net);
+	__ip_vs_control_cleanup(net);
+	__ip_vs_estimator_cleanup(net);
 	IP_VS_DBG(2, "ipvs netns %d released\n", net_ipvs(net)->gen);
 }
 
+static void __net_exit __ip_vs_dev_cleanup(struct net *net)
+{
+	EnterFunction(2);
+	net_ipvs(net)->enable = 0;	/* Disable packet reception */
+	__ip_vs_sync_cleanup(net);
+	LeaveFunction(2);
+}
+
 static struct pernet_operations ipvs_core_ops = {
 	.init = __ip_vs_init,
 	.exit = __ip_vs_cleanup,
@@ -1906,6 +1976,10 @@ static struct pernet_operations ipvs_core_ops = {
 	.size = sizeof(struct netns_ipvs),
 };
 
+static struct pernet_operations ipvs_core_dev_ops = {
+	.exit = __ip_vs_dev_cleanup,
+};
+
 /*
  *	Initialize IP Virtual Server
  */
@@ -1913,10 +1987,6 @@ static int __init ip_vs_init(void)
 {
 	int ret;
 
-	ret = register_pernet_subsys(&ipvs_core_ops);	/* Alloc ip_vs struct */
-	if (ret < 0)
-		return ret;
-
 	ip_vs_estimator_init();
 	ret = ip_vs_control_init();
 	if (ret < 0) {
@@ -1944,15 +2014,28 @@ static int __init ip_vs_init(void)
 		goto cleanup_conn;
 	}
 
+	ret = register_pernet_subsys(&ipvs_core_ops);	/* Alloc ip_vs struct */
+	if (ret < 0)
+		goto cleanup_sync;
+
+	ret = register_pernet_device(&ipvs_core_dev_ops);
+	if (ret < 0)
+		goto cleanup_sub;
+
 	ret = nf_register_hooks(ip_vs_ops, ARRAY_SIZE(ip_vs_ops));
 	if (ret < 0) {
 		pr_err("can't register hooks.\n");
-		goto cleanup_sync;
+		goto cleanup_dev;
 	}
 
 	pr_info("ipvs loaded.\n");
+
 	return ret;
 
+cleanup_dev:
+	unregister_pernet_device(&ipvs_core_dev_ops);
+cleanup_sub:
+	unregister_pernet_subsys(&ipvs_core_ops);
 cleanup_sync:
 	ip_vs_sync_cleanup();
   cleanup_conn:
@@ -1964,20 +2047,20 @@ cleanup_sync:
 	ip_vs_control_cleanup();
   cleanup_estimator:
 	ip_vs_estimator_cleanup();
-	unregister_pernet_subsys(&ipvs_core_ops);	/* free ip_vs struct */
 	return ret;
 }
 
 static void __exit ip_vs_cleanup(void)
 {
 	nf_unregister_hooks(ip_vs_ops, ARRAY_SIZE(ip_vs_ops));
+	unregister_pernet_device(&ipvs_core_dev_ops);
+	unregister_pernet_subsys(&ipvs_core_ops);	/* free ip_vs struct */
 	ip_vs_sync_cleanup();
 	ip_vs_conn_cleanup();
 	ip_vs_app_cleanup();
 	ip_vs_protocol_cleanup();
 	ip_vs_control_cleanup();
 	ip_vs_estimator_cleanup();
-	unregister_pernet_subsys(&ipvs_core_ops);	/* free ip_vs struct */
 	pr_info("ipvs unloaded.\n");
 }