[PATCH nf-next RFC 6/8] netfilter: nf_tables: get rid of pernet families

[Pablo Neira Ayuso <pablo@netfilter.org>]

Now that we have a single table list for each netns, we can get rid of
one pointer per family, thus, shrinking struct netns for nftables.

Call __nft_release_afinfo() from __net_exit path.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 include/net/netfilter/nf_tables.h       |  4 +--
 include/net/netns/nftables.h            |  6 -----
 net/bridge/netfilter/nf_tables_bridge.c | 38 ++++-----------------------
 net/ipv4/netfilter/nf_tables_arp.c      | 41 +++++++----------------------
 net/ipv4/netfilter/nf_tables_ipv4.c     | 40 ++++++----------------------
 net/ipv6/netfilter/nf_tables_ipv6.c     | 40 ++++++----------------------
 net/netfilter/nf_tables_api.c           | 40 +++++++++++++++-------------
 net/netfilter/nf_tables_inet.c          | 41 ++++++-----------------------
 net/netfilter/nf_tables_netdev.c        | 46 +++++++--------------------------
 9 files changed, 71 insertions(+), 225 deletions(-)

diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h
index fb7b560806f0..928d50bb3302 100644
--- a/include/net/netfilter/nf_tables.h
+++ b/include/net/netfilter/nf_tables.h
@@ -976,8 +976,8 @@ struct nft_af_info {
 	struct module			*owner;
 };
 
-int nft_register_afinfo(struct net *, struct nft_af_info *);
-void nft_unregister_afinfo(struct net *, struct nft_af_info *);
+int nft_register_afinfo(struct nft_af_info *);
+void nft_unregister_afinfo(struct nft_af_info *);
 
 int nft_register_chain_type(const struct nf_chain_type *);
 void nft_unregister_chain_type(const struct nf_chain_type *);
diff --git a/include/net/netns/nftables.h b/include/net/netns/nftables.h
index 7f86a63ac21f..44e4de0bb59b 100644
--- a/include/net/netns/nftables.h
+++ b/include/net/netns/nftables.h
@@ -10,12 +10,6 @@ struct netns_nftables {
 	struct list_head	af_info;
 	struct list_head	tables;
 	struct list_head	commit_list;
-	struct nft_af_info	*ipv4;
-	struct nft_af_info	*ipv6;
-	struct nft_af_info	*inet;
-	struct nft_af_info	*arp;
-	struct nft_af_info	*bridge;
-	struct nft_af_info	*netdev;
 	unsigned int		base_seq;
 	u8			gencursor;
 };
diff --git a/net/bridge/netfilter/nf_tables_bridge.c b/net/bridge/netfilter/nf_tables_bridge.c
index 66c97b1e3303..dbf7195f059c 100644
--- a/net/bridge/netfilter/nf_tables_bridge.c
+++ b/net/bridge/netfilter/nf_tables_bridge.c
@@ -47,34 +47,6 @@ static struct nft_af_info nft_af_bridge __read_mostly = {
 	.owner		= THIS_MODULE,
 };
 
-static int nf_tables_bridge_init_net(struct net *net)
-{
-	net->nft.bridge = kmalloc(sizeof(struct nft_af_info), GFP_KERNEL);
-	if (net->nft.bridge == NULL)
-		return -ENOMEM;
-
-	memcpy(net->nft.bridge, &nft_af_bridge, sizeof(nft_af_bridge));
-
-	if (nft_register_afinfo(net, net->nft.bridge) < 0)
-		goto err;
-
-	return 0;
-err:
-	kfree(net->nft.bridge);
-	return -ENOMEM;
-}
-
-static void nf_tables_bridge_exit_net(struct net *net)
-{
-	nft_unregister_afinfo(net, net->nft.bridge);
-	kfree(net->nft.bridge);
-}
-
-static struct pernet_operations nf_tables_bridge_net_ops = {
-	.init	= nf_tables_bridge_init_net,
-	.exit	= nf_tables_bridge_exit_net,
-};
-
 static const struct nf_chain_type filter_bridge = {
 	.name		= "filter",
 	.type		= NFT_CHAIN_T_DEFAULT,
@@ -98,17 +70,17 @@ static int __init nf_tables_bridge_init(void)
 {
 	int ret;
 
-	ret = nft_register_chain_type(&filter_bridge);
+	ret = nft_register_afinfo(&nft_af_bridge);
 	if (ret < 0)
 		return ret;
 
-	ret = register_pernet_subsys(&nf_tables_bridge_net_ops);
+	ret = nft_register_chain_type(&filter_bridge);
 	if (ret < 0)
-		goto err_register_subsys;
+		goto err_register_chain;
 
 	return ret;
 
-err_register_subsys:
+err_register_chain:
 	nft_unregister_chain_type(&filter_bridge);
 
 	return ret;
@@ -116,8 +88,8 @@ static int __init nf_tables_bridge_init(void)
 
 static void __exit nf_tables_bridge_exit(void)
 {
-	unregister_pernet_subsys(&nf_tables_bridge_net_ops);
 	nft_unregister_chain_type(&filter_bridge);
+	nft_unregister_afinfo(&nft_af_bridge);
 }
 
 module_init(nf_tables_bridge_init);
diff --git a/net/ipv4/netfilter/nf_tables_arp.c b/net/ipv4/netfilter/nf_tables_arp.c
index f9089b2ad905..07667388ceb5 100644
--- a/net/ipv4/netfilter/nf_tables_arp.c
+++ b/net/ipv4/netfilter/nf_tables_arp.c
@@ -32,34 +32,6 @@ static struct nft_af_info nft_af_arp __read_mostly = {
 	.owner		= THIS_MODULE,
 };
 
-static int nf_tables_arp_init_net(struct net *net)
-{
-	net->nft.arp = kmalloc(sizeof(struct nft_af_info), GFP_KERNEL);
-	if (net->nft.arp== NULL)
-		return -ENOMEM;
-
-	memcpy(net->nft.arp, &nft_af_arp, sizeof(nft_af_arp));
-
-	if (nft_register_afinfo(net, net->nft.arp) < 0)
-		goto err;
-
-	return 0;
-err:
-	kfree(net->nft.arp);
-	return -ENOMEM;
-}
-
-static void nf_tables_arp_exit_net(struct net *net)
-{
-	nft_unregister_afinfo(net, net->nft.arp);
-	kfree(net->nft.arp);
-}
-
-static struct pernet_operations nf_tables_arp_net_ops = {
-	.init   = nf_tables_arp_init_net,
-	.exit   = nf_tables_arp_exit_net,
-};
-
 static const struct nf_chain_type filter_arp = {
 	.name		= "filter",
 	.type		= NFT_CHAIN_T_DEFAULT,
@@ -77,21 +49,26 @@ static int __init nf_tables_arp_init(void)
 {
 	int ret;
 
-	ret = nft_register_chain_type(&filter_arp);
+	ret = nft_register_afinfo(&nft_af_arp);
 	if (ret < 0)
 		return ret;
 
-	ret = register_pernet_subsys(&nf_tables_arp_net_ops);
+	ret = nft_register_chain_type(&filter_arp);
 	if (ret < 0)
-		nft_unregister_chain_type(&filter_arp);
+		goto err_register_chain;
+
+	return 0;
+
+err_register_chain:
+	nft_unregister_chain_type(&filter_arp);
 
 	return ret;
 }
 
 static void __exit nf_tables_arp_exit(void)
 {
-	unregister_pernet_subsys(&nf_tables_arp_net_ops);
 	nft_unregister_chain_type(&filter_arp);
+	nft_unregister_afinfo(&nft_af_arp);
 }
 
 module_init(nf_tables_arp_init);
diff --git a/net/ipv4/netfilter/nf_tables_ipv4.c b/net/ipv4/netfilter/nf_tables_ipv4.c
index a98f2de63771..e1441738acb4 100644
--- a/net/ipv4/netfilter/nf_tables_ipv4.c
+++ b/net/ipv4/netfilter/nf_tables_ipv4.c
@@ -35,34 +35,6 @@ static struct nft_af_info nft_af_ipv4 __read_mostly = {
 	.owner		= THIS_MODULE,
 };
 
-static int nf_tables_ipv4_init_net(struct net *net)
-{
-	net->nft.ipv4 = kmalloc(sizeof(struct nft_af_info), GFP_KERNEL);
-	if (net->nft.ipv4 == NULL)
-		return -ENOMEM;
-
-	memcpy(net->nft.ipv4, &nft_af_ipv4, sizeof(nft_af_ipv4));
-
-	if (nft_register_afinfo(net, net->nft.ipv4) < 0)
-		goto err;
-
-	return 0;
-err:
-	kfree(net->nft.ipv4);
-	return -ENOMEM;
-}
-
-static void nf_tables_ipv4_exit_net(struct net *net)
-{
-	nft_unregister_afinfo(net, net->nft.ipv4);
-	kfree(net->nft.ipv4);
-}
-
-static struct pernet_operations nf_tables_ipv4_net_ops = {
-	.init	= nf_tables_ipv4_init_net,
-	.exit	= nf_tables_ipv4_exit_net,
-};
-
 static const struct nf_chain_type filter_ipv4 = {
 	.name		= "filter",
 	.type		= NFT_CHAIN_T_DEFAULT,
@@ -86,21 +58,25 @@ static int __init nf_tables_ipv4_init(void)
 {
 	int ret;
 
-	ret = nft_register_chain_type(&filter_ipv4);
+	ret = nft_register_afinfo(&nft_af_ipv4);
 	if (ret < 0)
 		return ret;
 
-	ret = register_pernet_subsys(&nf_tables_ipv4_net_ops);
+	ret = nft_register_chain_type(&filter_ipv4);
 	if (ret < 0)
-		nft_unregister_chain_type(&filter_ipv4);
+		goto err_register_chain;
+
+	return 0;
 
+err_register_chain:
+	nft_unregister_afinfo(&nft_af_ipv4);
 	return ret;
 }
 
 static void __exit nf_tables_ipv4_exit(void)
 {
-	unregister_pernet_subsys(&nf_tables_ipv4_net_ops);
 	nft_unregister_chain_type(&filter_ipv4);
+	nft_unregister_afinfo(&nft_af_ipv4);
 }
 
 module_init(nf_tables_ipv4_init);
diff --git a/net/ipv6/netfilter/nf_tables_ipv6.c b/net/ipv6/netfilter/nf_tables_ipv6.c
index bddd39dc1cf3..912d0e5516b0 100644
--- a/net/ipv6/netfilter/nf_tables_ipv6.c
+++ b/net/ipv6/netfilter/nf_tables_ipv6.c
@@ -33,34 +33,6 @@ static struct nft_af_info nft_af_ipv6 __read_mostly = {
 	.owner		= THIS_MODULE,
 };
 
-static int nf_tables_ipv6_init_net(struct net *net)
-{
-	net->nft.ipv6 = kmalloc(sizeof(struct nft_af_info), GFP_KERNEL);
-	if (net->nft.ipv6 == NULL)
-		return -ENOMEM;
-
-	memcpy(net->nft.ipv6, &nft_af_ipv6, sizeof(nft_af_ipv6));
-
-	if (nft_register_afinfo(net, net->nft.ipv6) < 0)
-		goto err;
-
-	return 0;
-err:
-	kfree(net->nft.ipv6);
-	return -ENOMEM;
-}
-
-static void nf_tables_ipv6_exit_net(struct net *net)
-{
-	nft_unregister_afinfo(net, net->nft.ipv6);
-	kfree(net->nft.ipv6);
-}
-
-static struct pernet_operations nf_tables_ipv6_net_ops = {
-	.init	= nf_tables_ipv6_init_net,
-	.exit	= nf_tables_ipv6_exit_net,
-};
-
 static const struct nf_chain_type filter_ipv6 = {
 	.name		= "filter",
 	.type		= NFT_CHAIN_T_DEFAULT,
@@ -84,20 +56,24 @@ static int __init nf_tables_ipv6_init(void)
 {
 	int ret;
 
-	ret = nft_register_chain_type(&filter_ipv6);
+	ret = nft_register_afinfo(&nft_af_ipv6);
 	if (ret < 0)
 		return ret;
 
-	ret = register_pernet_subsys(&nf_tables_ipv6_net_ops);
+	ret = nft_register_chain_type(&filter_ipv6);
 	if (ret < 0)
-		nft_unregister_chain_type(&filter_ipv6);
+		goto err_register_chain;
+
+	return 0;
 
+err_register_chain:
+	nft_unregister_afinfo(&nft_af_ipv6);
 	return ret;
 }
 
 static void __exit nf_tables_ipv6_exit(void)
 {
-	unregister_pernet_subsys(&nf_tables_ipv6_net_ops);
+	nft_unregister_afinfo(&nft_af_ipv6);
 	nft_unregister_chain_type(&filter_ipv6);
 }
 
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 3505cca8262f..0e5e0f76a664 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -24,6 +24,7 @@
 
 static LIST_HEAD(nf_tables_expressions);
 static LIST_HEAD(nf_tables_objects);
+static LIST_HEAD(nf_tables_af_info);
 
 /**
  *	nft_register_afinfo - register nf_tables address family info
@@ -33,17 +34,15 @@ static LIST_HEAD(nf_tables_objects);
  *	Register the address family for use with nf_tables. Returns zero on
  *	success or a negative errno code otherwise.
  */
-int nft_register_afinfo(struct net *net, struct nft_af_info *afi)
+int nft_register_afinfo(struct nft_af_info *afi)
 {
 	nfnl_lock(NFNL_SUBSYS_NFTABLES);
-	list_add_tail_rcu(&afi->list, &net->nft.af_info);
+	list_add_tail_rcu(&afi->list, &nf_tables_af_info);
 	nfnl_unlock(NFNL_SUBSYS_NFTABLES);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(nft_register_afinfo);
 
-static void __nft_release_afinfo(struct net *net, struct nft_af_info *afi);
-
 /**
  *	nft_unregister_afinfo - unregister nf_tables address family info
  *
@@ -51,10 +50,9 @@ static void __nft_release_afinfo(struct net *net, struct nft_af_info *afi);
  *
  *	Unregister the address family for use with nf_tables.
  */
-void nft_unregister_afinfo(struct net *net, struct nft_af_info *afi)
+void nft_unregister_afinfo(struct nft_af_info *afi)
 {
 	nfnl_lock(NFNL_SUBSYS_NFTABLES);
-	__nft_release_afinfo(net, afi);
 	list_del_rcu(&afi->list);
 	nfnl_unlock(NFNL_SUBSYS_NFTABLES);
 }
@@ -5800,15 +5798,6 @@ int nft_data_dump(struct sk_buff *skb, int attr, const struct nft_data *data,
 }
 EXPORT_SYMBOL_GPL(nft_data_dump);
 
-static int __net_init nf_tables_init_net(struct net *net)
-{
-	INIT_LIST_HEAD(&net->nft.af_info);
-	INIT_LIST_HEAD(&net->nft.tables);
-	INIT_LIST_HEAD(&net->nft.commit_list);
-	net->nft.base_seq = 1;
-	return 0;
-}
-
 int __nft_release_basechain(struct nft_ctx *ctx)
 {
 	struct nft_rule *rule, *nr;
@@ -5829,8 +5818,7 @@ int __nft_release_basechain(struct nft_ctx *ctx)
 }
 EXPORT_SYMBOL_GPL(__nft_release_basechain);
 
-/* Called by nft_unregister_afinfo() from __net_exit path, nfnl_lock is held. */
-static void __nft_release_afinfo(struct net *net, struct nft_af_info *afi)
+static void __nft_release_afinfo(struct net *net)
 {
 	struct nft_table *table, *nt;
 	struct nft_chain *chain, *nc;
@@ -5839,10 +5827,11 @@ static void __nft_release_afinfo(struct net *net, struct nft_af_info *afi)
 	struct nft_set *set, *ns;
 	struct nft_ctx ctx = {
 		.net	= net,
-		.family	= afi->family,
 	};
 
 	list_for_each_entry_safe(table, nt, &net->nft.tables, list) {
+		ctx.family = table->afi->family;
+
 		list_for_each_entry(chain, &table->chains, list)
 			nf_tables_unregister_hook(net, table, chain);
 		/* No packets are walking on these chains anymore. */
@@ -5875,8 +5864,23 @@ static void __nft_release_afinfo(struct net *net, struct nft_af_info *afi)
 	}
 }
 
+static int __net_init nf_tables_init_net(struct net *net)
+{
+	INIT_LIST_HEAD(&net->nft.af_info);
+	INIT_LIST_HEAD(&net->nft.tables);
+	INIT_LIST_HEAD(&net->nft.commit_list);
+	net->nft.base_seq = 1;
+	return 0;
+}
+
+static void __net_exit nf_tables_exit_net(struct net *net)
+{
+	__nft_release_afinfo(net);
+}
+
 static struct pernet_operations nf_tables_net_ops = {
 	.init	= nf_tables_init_net,
+	.exit	= nf_tables_exit_net,
 };
 
 static int __init nf_tables_module_init(void)
diff --git a/net/netfilter/nf_tables_inet.c b/net/netfilter/nf_tables_inet.c
index 5128ffd053df..c77b27b501c7 100644
--- a/net/netfilter/nf_tables_inet.c
+++ b/net/netfilter/nf_tables_inet.c
@@ -64,34 +64,6 @@ static struct nft_af_info nft_af_inet __read_mostly = {
 	.owner		= THIS_MODULE,
 };
 
-static int __net_init nf_tables_inet_init_net(struct net *net)
-{
-	net->nft.inet = kmalloc(sizeof(struct nft_af_info), GFP_KERNEL);
-	if (net->nft.inet == NULL)
-		return -ENOMEM;
-	memcpy(net->nft.inet, &nft_af_inet, sizeof(nft_af_inet));
-
-	if (nft_register_afinfo(net, net->nft.inet) < 0)
-		goto err;
-
-	return 0;
-
-err:
-	kfree(net->nft.inet);
-	return -ENOMEM;
-}
-
-static void __net_exit nf_tables_inet_exit_net(struct net *net)
-{
-	nft_unregister_afinfo(net, net->nft.inet);
-	kfree(net->nft.inet);
-}
-
-static struct pernet_operations nf_tables_inet_net_ops = {
-	.init	= nf_tables_inet_init_net,
-	.exit	= nf_tables_inet_exit_net,
-};
-
 static const struct nf_chain_type filter_inet = {
 	.name		= "filter",
 	.type		= NFT_CHAIN_T_DEFAULT,
@@ -115,21 +87,24 @@ static int __init nf_tables_inet_init(void)
 {
 	int ret;
 
-	ret = nft_register_chain_type(&filter_inet);
-	if (ret < 0)
+	if (nft_register_afinfo(&nft_af_inet) < 0)
 		return ret;
 
-	ret = register_pernet_subsys(&nf_tables_inet_net_ops);
+	ret = nft_register_chain_type(&filter_inet);
 	if (ret < 0)
-		nft_unregister_chain_type(&filter_inet);
+		goto err_register_chain;
+
+	return ret;
 
+err_register_chain:
+	nft_unregister_afinfo(&nft_af_inet);
 	return ret;
 }
 
 static void __exit nf_tables_inet_exit(void)
 {
-	unregister_pernet_subsys(&nf_tables_inet_net_ops);
 	nft_unregister_chain_type(&filter_inet);
+	nft_unregister_afinfo(&nft_af_inet);
 }
 
 module_init(nf_tables_inet_init);
diff --git a/net/netfilter/nf_tables_netdev.c b/net/netfilter/nf_tables_netdev.c
index 01b61a67a2ac..404b49acb125 100644
--- a/net/netfilter/nf_tables_netdev.c
+++ b/net/netfilter/nf_tables_netdev.c
@@ -43,34 +43,6 @@ static struct nft_af_info nft_af_netdev __read_mostly = {
 	.owner		= THIS_MODULE,
 };
 
-static int nf_tables_netdev_init_net(struct net *net)
-{
-	net->nft.netdev = kmalloc(sizeof(struct nft_af_info), GFP_KERNEL);
-	if (net->nft.netdev == NULL)
-		return -ENOMEM;
-
-	memcpy(net->nft.netdev, &nft_af_netdev, sizeof(nft_af_netdev));
-
-	if (nft_register_afinfo(net, net->nft.netdev) < 0)
-		goto err;
-
-	return 0;
-err:
-	kfree(net->nft.netdev);
-	return -ENOMEM;
-}
-
-static void nf_tables_netdev_exit_net(struct net *net)
-{
-	nft_unregister_afinfo(net, net->nft.netdev);
-	kfree(net->nft.netdev);
-}
-
-static struct pernet_operations nf_tables_netdev_net_ops = {
-	.init	= nf_tables_netdev_init_net,
-	.exit	= nf_tables_netdev_exit_net,
-};
-
 static const struct nf_chain_type nft_filter_chain_netdev = {
 	.name		= "filter",
 	.type		= NFT_CHAIN_T_DEFAULT,
@@ -145,32 +117,32 @@ static int __init nf_tables_netdev_init(void)
 {
 	int ret;
 
-	ret = nft_register_chain_type(&nft_filter_chain_netdev);
-	if (ret)
+	if (nft_register_afinfo(&nft_af_netdev) < 0)
 		return ret;
 
-	ret = register_pernet_subsys(&nf_tables_netdev_net_ops);
+	ret = nft_register_chain_type(&nft_filter_chain_netdev);
 	if (ret)
-		goto err1;
+		goto err_register_chain_type;
 
 	ret = register_netdevice_notifier(&nf_tables_netdev_notifier);
 	if (ret)
-		goto err2;
+		goto err_register_netdevice_notifier;
 
 	return 0;
 
-err2:
-	unregister_pernet_subsys(&nf_tables_netdev_net_ops);
-err1:
+err_register_netdevice_notifier:
 	nft_unregister_chain_type(&nft_filter_chain_netdev);
+err_register_chain_type:
+	nft_unregister_afinfo(&nft_af_netdev);
+
 	return ret;
 }
 
 static void __exit nf_tables_netdev_exit(void)
 {
 	unregister_netdevice_notifier(&nf_tables_netdev_notifier);
-	unregister_pernet_subsys(&nf_tables_netdev_net_ops);
 	nft_unregister_chain_type(&nft_filter_chain_netdev);
+	nft_unregister_afinfo(&nft_af_netdev);
 }
 
 module_init(nf_tables_netdev_init);
-- 
2.11.0