[PATCH 00/17] netfilter: netfilter update

[PATCH 00/17] netfilter: netfilter update

[kaber]

following is a first netfilter update for net-next, containing:

- RCU conversions for nfnetlink_log, nfnetlink_queue, ip_queue, ip6_queue
  and ipt_CLUSTERIP from Eric

- conversion of the untracked conntrack structure to per-cpu data, from Eric

- removal of the nth_lock spinlock, from Eric

- conversion of bridge netfilter to skb_set_noref, from Eric

- a new IDLETIMER target, which can be used to trigger sysfs notifications
  when a certain xtables rule hasn't been hit for a specific time, from
  Luciano Coelho

- removal of some atomic ops in netfilter IPv6 defragmentation, from Shan Wei

- minor cleanups in xt_sctp and the netfilter checksumming function, from
  Shan Wei

Please pull from:

git://git.kernel.org/pub/scm/linux/kernel/git/kaber/nf-next-2.6.git master

Thanks!

[PATCH 01/17] netfilter: br_netfilter: use skb_set_noref()

[kaber]

From: Eric Dumazet <eric.dumazet@gmail.com>

Avoid dirtying bridge_parent_rtable refcount, using new dst noref
infrastructure.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
---
 net/bridge/br_netfilter.c |    6 ++----
 1 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/net/bridge/br_netfilter.c b/net/bridge/br_netfilter.c
index 4442099..cbea5af 100644
--- a/net/bridge/br_netfilter.c
+++ b/net/bridge/br_netfilter.c
@@ -244,8 +244,7 @@ static int br_nf_pre_routing_finish_ipv6(struct sk_buff *skb)
 		kfree_skb(skb);
 		return 0;
 	}
-	dst_hold(&rt->u.dst);
-	skb_dst_set(skb, &rt->u.dst);
+	skb_dst_set_noref(skb, &rt->u.dst);
 
 	skb->dev = nf_bridge->physindev;
 	nf_bridge_update_protocol(skb);
@@ -396,8 +395,7 @@ bridged_dnat:
 			kfree_skb(skb);
 			return 0;
 		}
-		dst_hold(&rt->u.dst);
-		skb_dst_set(skb, &rt->u.dst);
+		skb_dst_set_noref(skb, &rt->u.dst);
 	}
 
 	skb->dev = nf_bridge->physindev;
-- 
1.7.0.4

[PATCH 02/17] netfilter: xt_statistic: remove nth_lock spinlock

[kaber]

From: Eric Dumazet <eric.dumazet@gmail.com>

Use atomic_cmpxchg() to avoid dirtying a shared location.

xt_statistic_priv smp aligned to avoid sharing same cache line with
other stuff.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
---
 net/netfilter/xt_statistic.c |   19 +++++++++----------
 1 files changed, 9 insertions(+), 10 deletions(-)

diff --git a/net/netfilter/xt_statistic.c b/net/netfilter/xt_statistic.c
index 96e62b8..42ecb71 100644
--- a/net/netfilter/xt_statistic.c
+++ b/net/netfilter/xt_statistic.c
@@ -18,8 +18,8 @@
 #include <linux/netfilter/x_tables.h>
 
 struct xt_statistic_priv {
-	uint32_t count;
-};
+	atomic_t count;
+} ____cacheline_aligned_in_smp;
 
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
@@ -27,13 +27,12 @@ MODULE_DESCRIPTION("Xtables: statistics-based matching (\"Nth\", random)");
 MODULE_ALIAS("ipt_statistic");
 MODULE_ALIAS("ip6t_statistic");
 
-static DEFINE_SPINLOCK(nth_lock);
-
 static bool
 statistic_mt(const struct sk_buff *skb, struct xt_action_param *par)
 {
 	const struct xt_statistic_info *info = par->matchinfo;
 	bool ret = info->flags & XT_STATISTIC_INVERT;
+	int nval, oval;
 
 	switch (info->mode) {
 	case XT_STATISTIC_MODE_RANDOM:
@@ -41,12 +40,12 @@ statistic_mt(const struct sk_buff *skb, struct xt_action_param *par)
 			ret = !ret;
 		break;
 	case XT_STATISTIC_MODE_NTH:
-		spin_lock_bh(&nth_lock);
-		if (info->master->count++ == info->u.nth.every) {
-			info->master->count = 0;
+		do {
+			oval = atomic_read(&info->master->count);
+			nval = (oval == info->u.nth.every) ? 0 : oval + 1;
+		} while (atomic_cmpxchg(&info->master->count, oval, nval) != oval);
+		if (nval == 0)
 			ret = !ret;
-		}
-		spin_unlock_bh(&nth_lock);
 		break;
 	}
 
@@ -64,7 +63,7 @@ static int statistic_mt_check(const struct xt_mtchk_param *par)
 	info->master = kzalloc(sizeof(*info->master), GFP_KERNEL);
 	if (info->master == NULL)
 		return -ENOMEM;
-	info->master->count = info->u.nth.count;
+	atomic_set(&info->master->count, info->u.nth.count);
 
 	return 0;
 }
-- 
1.7.0.4

[PATCH 03/17] netfilter: vmalloc_node cleanup

[kaber]

From: Eric Dumazet <eric.dumazet@gmail.com>

Using vmalloc_node(size, numa_node_id()) for temporary storage is not
needed. vmalloc(size) is more respectful of user NUMA policy.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
---
 net/ipv4/netfilter/arp_tables.c |    7 +++----
 net/ipv4/netfilter/ip_tables.c  |    4 ++--
 net/ipv6/netfilter/ip6_tables.c |    7 +++----
 3 files changed, 8 insertions(+), 10 deletions(-)

diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c
index 1ac01b1..16c0ba0 100644
--- a/net/ipv4/netfilter/arp_tables.c
+++ b/net/ipv4/netfilter/arp_tables.c
@@ -758,7 +758,7 @@ static struct xt_counters *alloc_counters(const struct xt_table *table)
 	 * about).
 	 */
 	countersize = sizeof(struct xt_counters) * private->number;
-	counters = vmalloc_node(countersize, numa_node_id());
+	counters = vmalloc(countersize);
 
 	if (counters == NULL)
 		return ERR_PTR(-ENOMEM);
@@ -1005,8 +1005,7 @@ static int __do_replace(struct net *net, const char *name,
 	struct arpt_entry *iter;
 
 	ret = 0;
-	counters = vmalloc_node(num_counters * sizeof(struct xt_counters),
-				numa_node_id());
+	counters = vmalloc(num_counters * sizeof(struct xt_counters));
 	if (!counters) {
 		ret = -ENOMEM;
 		goto out;
@@ -1159,7 +1158,7 @@ static int do_add_counters(struct net *net, const void __user *user,
 	if (len != size + num_counters * sizeof(struct xt_counters))
 		return -EINVAL;
 
-	paddc = vmalloc_node(len - size, numa_node_id());
+	paddc = vmalloc(len - size);
 	if (!paddc)
 		return -ENOMEM;
 
diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c
index 63958f3..7c0b8ad 100644
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -928,7 +928,7 @@ static struct xt_counters *alloc_counters(const struct xt_table *table)
 	   (other than comefrom, which userspace doesn't care
 	   about). */
 	countersize = sizeof(struct xt_counters) * private->number;
-	counters = vmalloc_node(countersize, numa_node_id());
+	counters = vmalloc(countersize);
 
 	if (counters == NULL)
 		return ERR_PTR(-ENOMEM);
@@ -1352,7 +1352,7 @@ do_add_counters(struct net *net, const void __user *user,
 	if (len != size + num_counters * sizeof(struct xt_counters))
 		return -EINVAL;
 
-	paddc = vmalloc_node(len - size, numa_node_id());
+	paddc = vmalloc(len - size);
 	if (!paddc)
 		return -ENOMEM;
 
diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c
index 6f517bd..82945ef 100644
--- a/net/ipv6/netfilter/ip6_tables.c
+++ b/net/ipv6/netfilter/ip6_tables.c
@@ -943,7 +943,7 @@ static struct xt_counters *alloc_counters(const struct xt_table *table)
 	   (other than comefrom, which userspace doesn't care
 	   about). */
 	countersize = sizeof(struct xt_counters) * private->number;
-	counters = vmalloc_node(countersize, numa_node_id());
+	counters = vmalloc(countersize);
 
 	if (counters == NULL)
 		return ERR_PTR(-ENOMEM);
@@ -1213,8 +1213,7 @@ __do_replace(struct net *net, const char *name, unsigned int valid_hooks,
 	struct ip6t_entry *iter;
 
 	ret = 0;
-	counters = vmalloc_node(num_counters * sizeof(struct xt_counters),
-				numa_node_id());
+	counters = vmalloc(num_counters * sizeof(struct xt_counters));
 	if (!counters) {
 		ret = -ENOMEM;
 		goto out;
@@ -1368,7 +1367,7 @@ do_add_counters(struct net *net, const void __user *user, unsigned int len,
 	if (len != size + num_counters * sizeof(struct xt_counters))
 		return -EINVAL;
 
-	paddc = vmalloc_node(len - size, numa_node_id());
+	paddc = vmalloc(len - size);
 	if (!paddc)
 		return -ENOMEM;
 
-- 
1.7.0.4

[PATCH 04/17] netfilter: xt_rateest: Better struct xt_rateest layout

[kaber]

From: Eric Dumazet <eric.dumazet@gmail.com>

We currently dirty two cache lines in struct xt_rateest, this hurts SMP
performance.

This patch moves lock/bstats/rstats at beginning of structure so that
they share a single cache line.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
---
 include/net/netfilter/xt_rateest.h |   10 +++++++---
 1 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/include/net/netfilter/xt_rateest.h b/include/net/netfilter/xt_rateest.h
index ddbf37e..b1d780e 100644
--- a/include/net/netfilter/xt_rateest.h
+++ b/include/net/netfilter/xt_rateest.h
@@ -2,13 +2,17 @@
 #define _XT_RATEEST_H
 
 struct xt_rateest {
+	/* keep lock and bstats on same cache line to speedup xt_rateest_tg() */
+	struct gnet_stats_basic_packed	bstats;
+	spinlock_t			lock;
+	/* keep rstats and lock on same cache line to speedup xt_rateest_mt() */
+	struct gnet_stats_rate_est	rstats;
+
+	/* following fields not accessed in hot path */
 	struct hlist_node		list;
 	char				name[IFNAMSIZ];
 	unsigned int			refcnt;
-	spinlock_t			lock;
 	struct gnet_estimator		params;
-	struct gnet_stats_rate_est	rstats;
-	struct gnet_stats_basic_packed	bstats;
 };
 
 extern struct xt_rateest *xt_rateest_lookup(const char *name);
-- 
1.7.0.4

[PATCH 05/17] netfilter: nf_conntrack: IPS_UNTRACKED bit

[kaber]

From: Eric Dumazet <eric.dumazet@gmail.com>

NOTRACK makes all cpus share a cache line on nf_conntrack_untracked
twice per packet. This is bad for performance.
__read_mostly annotation is also a bad choice.

This patch introduces IPS_UNTRACKED bit so that we can use later a
per_cpu untrack structure more easily.

A new helper, nf_ct_untracked_get() returns a pointer to
nf_conntrack_untracked.

Another one, nf_ct_untracked_status_or() is used by nf_nat_init() to add
IPS_NAT_DONE_MASK bits to untracked status.

nf_ct_is_untracked() prototype is changed to work on a nf_conn pointer.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
---
 include/linux/netfilter/nf_conntrack_common.h  |    4 ++++
 include/net/netfilter/nf_conntrack.h           |   12 +++++++++---
 include/net/netfilter/nf_conntrack_core.h      |    2 +-
 net/ipv4/netfilter/nf_nat_core.c               |    2 +-
 net/ipv4/netfilter/nf_nat_standalone.c         |    2 +-
 net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c |    2 +-
 net/netfilter/nf_conntrack_core.c              |   11 ++++++++---
 net/netfilter/nf_conntrack_netlink.c           |    2 +-
 net/netfilter/xt_CT.c                          |    4 ++--
 net/netfilter/xt_NOTRACK.c                     |    2 +-
 net/netfilter/xt_TEE.c                         |    4 ++--
 net/netfilter/xt_cluster.c                     |    2 +-
 net/netfilter/xt_conntrack.c                   |   11 ++++++-----
 net/netfilter/xt_socket.c                      |    2 +-
 net/netfilter/xt_state.c                       |   14 ++++++++------
 15 files changed, 47 insertions(+), 29 deletions(-)

diff --git a/include/linux/netfilter/nf_conntrack_common.h b/include/linux/netfilter/nf_conntrack_common.h
index 14e6d32..1afd18c 100644
--- a/include/linux/netfilter/nf_conntrack_common.h
+++ b/include/linux/netfilter/nf_conntrack_common.h
@@ -76,6 +76,10 @@ enum ip_conntrack_status {
 	/* Conntrack is a template */
 	IPS_TEMPLATE_BIT = 11,
 	IPS_TEMPLATE = (1 << IPS_TEMPLATE_BIT),
+
+	/* Conntrack is a fake untracked entry */
+	IPS_UNTRACKED_BIT = 12,
+	IPS_UNTRACKED = (1 << IPS_UNTRACKED_BIT),
 };
 
 /* Connection tracking event types */
diff --git a/include/net/netfilter/nf_conntrack.h b/include/net/netfilter/nf_conntrack.h
index bde095f..3bc38c7 100644
--- a/include/net/netfilter/nf_conntrack.h
+++ b/include/net/netfilter/nf_conntrack.h
@@ -261,7 +261,13 @@ extern s16 (*nf_ct_nat_offset)(const struct nf_conn *ct,
 			       u32 seq);
 
 /* Fake conntrack entry for untracked connections */
-extern struct nf_conn nf_conntrack_untracked;
+static inline struct nf_conn *nf_ct_untracked_get(void)
+{
+	extern struct nf_conn nf_conntrack_untracked;
+
+	return &nf_conntrack_untracked;
+}
+extern void nf_ct_untracked_status_or(unsigned long bits);
 
 /* Iterate over all conntracks: if iter returns true, it's deleted. */
 extern void
@@ -289,9 +295,9 @@ static inline int nf_ct_is_dying(struct nf_conn *ct)
 	return test_bit(IPS_DYING_BIT, &ct->status);
 }
 
-static inline int nf_ct_is_untracked(const struct sk_buff *skb)
+static inline int nf_ct_is_untracked(const struct nf_conn *ct)
 {
-	return (skb->nfct == &nf_conntrack_untracked.ct_general);
+	return test_bit(IPS_UNTRACKED_BIT, &ct->status);
 }
 
 extern int nf_conntrack_set_hashsize(const char *val, struct kernel_param *kp);
diff --git a/include/net/netfilter/nf_conntrack_core.h b/include/net/netfilter/nf_conntrack_core.h
index 3d7524f..aced085 100644
--- a/include/net/netfilter/nf_conntrack_core.h
+++ b/include/net/netfilter/nf_conntrack_core.h
@@ -60,7 +60,7 @@ static inline int nf_conntrack_confirm(struct sk_buff *skb)
 	struct nf_conn *ct = (struct nf_conn *)skb->nfct;
 	int ret = NF_ACCEPT;
 
-	if (ct && ct != &nf_conntrack_untracked) {
+	if (ct && !nf_ct_is_untracked(ct)) {
 		if (!nf_ct_is_confirmed(ct))
 			ret = __nf_conntrack_confirm(skb);
 		if (likely(ret == NF_ACCEPT))
diff --git a/net/ipv4/netfilter/nf_nat_core.c b/net/ipv4/netfilter/nf_nat_core.c
index 4f8bddb..c7719b2 100644
--- a/net/ipv4/netfilter/nf_nat_core.c
+++ b/net/ipv4/netfilter/nf_nat_core.c
@@ -742,7 +742,7 @@ static int __init nf_nat_init(void)
 	spin_unlock_bh(&nf_nat_lock);
 
 	/* Initialize fake conntrack so that NAT will skip it */
-	nf_conntrack_untracked.status |= IPS_NAT_DONE_MASK;
+	nf_ct_untracked_status_or(IPS_NAT_DONE_MASK);
 
 	l3proto = nf_ct_l3proto_find_get((u_int16_t)AF_INET);
 
diff --git a/net/ipv4/netfilter/nf_nat_standalone.c b/net/ipv4/netfilter/nf_nat_standalone.c
index beb2581..6723c68 100644
--- a/net/ipv4/netfilter/nf_nat_standalone.c
+++ b/net/ipv4/netfilter/nf_nat_standalone.c
@@ -98,7 +98,7 @@ nf_nat_fn(unsigned int hooknum,
 		return NF_ACCEPT;
 
 	/* Don't try to NAT if this packet is not conntracked */
-	if (ct == &nf_conntrack_untracked)
+	if (nf_ct_is_untracked(ct))
 		return NF_ACCEPT;
 
 	nat = nfct_nat(ct);
diff --git a/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c b/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c
index 9be8177..1df3c8b 100644
--- a/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c
+++ b/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c
@@ -208,7 +208,7 @@ icmpv6_error(struct net *net, struct nf_conn *tmpl,
 	type = icmp6h->icmp6_type - 130;
 	if (type >= 0 && type < sizeof(noct_valid_new) &&
 	    noct_valid_new[type]) {
-		skb->nfct = &nf_conntrack_untracked.ct_general;
+		skb->nfct = &nf_ct_untracked_get()->ct_general;
 		skb->nfctinfo = IP_CT_NEW;
 		nf_conntrack_get(skb->nfct);
 		return NF_ACCEPT;
diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c
index eeeb8bc..6c1da21 100644
--- a/net/netfilter/nf_conntrack_core.c
+++ b/net/netfilter/nf_conntrack_core.c
@@ -62,7 +62,7 @@ EXPORT_SYMBOL_GPL(nf_conntrack_htable_size);
 unsigned int nf_conntrack_max __read_mostly;
 EXPORT_SYMBOL_GPL(nf_conntrack_max);
 
-struct nf_conn nf_conntrack_untracked __read_mostly;
+struct nf_conn nf_conntrack_untracked;
 EXPORT_SYMBOL_GPL(nf_conntrack_untracked);
 
 static int nf_conntrack_hash_rnd_initted;
@@ -1321,6 +1321,12 @@ EXPORT_SYMBOL_GPL(nf_conntrack_set_hashsize);
 module_param_call(hashsize, nf_conntrack_set_hashsize, param_get_uint,
 		  &nf_conntrack_htable_size, 0600);
 
+void nf_ct_untracked_status_or(unsigned long bits)
+{
+	nf_conntrack_untracked.status |= bits;
+}
+EXPORT_SYMBOL_GPL(nf_ct_untracked_status_or);
+
 static int nf_conntrack_init_init_net(void)
 {
 	int max_factor = 8;
@@ -1368,8 +1374,7 @@ static int nf_conntrack_init_init_net(void)
 #endif
 	atomic_set(&nf_conntrack_untracked.ct_general.use, 1);
 	/*  - and look it like as a confirmed connection */
-	set_bit(IPS_CONFIRMED_BIT, &nf_conntrack_untracked.status);
-
+	nf_ct_untracked_status_or(IPS_CONFIRMED | IPS_UNTRACKED);
 	return 0;
 
 #ifdef CONFIG_NF_CONNTRACK_ZONES
diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
index c42ff6a..5bae1cd 100644
--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c
@@ -480,7 +480,7 @@ ctnetlink_conntrack_event(unsigned int events, struct nf_ct_event *item)
 	int err;
 
 	/* ignore our fake conntrack entry */
-	if (ct == &nf_conntrack_untracked)
+	if (nf_ct_is_untracked(ct))
 		return 0;
 
 	if (events & (1 << IPCT_DESTROY)) {
diff --git a/net/netfilter/xt_CT.c b/net/netfilter/xt_CT.c
index 562bf32..0cb6053 100644
--- a/net/netfilter/xt_CT.c
+++ b/net/netfilter/xt_CT.c
@@ -67,7 +67,7 @@ static int xt_ct_tg_check(const struct xt_tgchk_param *par)
 		return -EINVAL;
 
 	if (info->flags & XT_CT_NOTRACK) {
-		ct = &nf_conntrack_untracked;
+		ct = nf_ct_untracked_get();
 		atomic_inc(&ct->ct_general.use);
 		goto out;
 	}
@@ -132,7 +132,7 @@ static void xt_ct_tg_destroy(const struct xt_tgdtor_param *par)
 	struct nf_conn *ct = info->ct;
 	struct nf_conn_help *help;
 
-	if (ct != &nf_conntrack_untracked) {
+	if (!nf_ct_is_untracked(ct)) {
 		help = nfct_help(ct);
 		if (help)
 			module_put(help->helper->me);
diff --git a/net/netfilter/xt_NOTRACK.c b/net/netfilter/xt_NOTRACK.c
index 512b912..9d78218 100644
--- a/net/netfilter/xt_NOTRACK.c
+++ b/net/netfilter/xt_NOTRACK.c
@@ -23,7 +23,7 @@ notrack_tg(struct sk_buff *skb, const struct xt_action_param *par)
 	   If there is a real ct entry correspondig to this packet,
 	   it'll hang aroun till timing out. We don't deal with it
 	   for performance reasons. JK */
-	skb->nfct = &nf_conntrack_untracked.ct_general;
+	skb->nfct = &nf_ct_untracked_get()->ct_general;
 	skb->nfctinfo = IP_CT_NEW;
 	nf_conntrack_get(skb->nfct);
 
diff --git a/net/netfilter/xt_TEE.c b/net/netfilter/xt_TEE.c
index 859d9fd..7a11826 100644
--- a/net/netfilter/xt_TEE.c
+++ b/net/netfilter/xt_TEE.c
@@ -104,7 +104,7 @@ tee_tg4(struct sk_buff *skb, const struct xt_action_param *par)
 #ifdef WITH_CONNTRACK
 	/* Avoid counting cloned packets towards the original connection. */
 	nf_conntrack_put(skb->nfct);
-	skb->nfct     = &nf_conntrack_untracked.ct_general;
+	skb->nfct     = &nf_ct_untracked_get()->ct_general;
 	skb->nfctinfo = IP_CT_NEW;
 	nf_conntrack_get(skb->nfct);
 #endif
@@ -177,7 +177,7 @@ tee_tg6(struct sk_buff *skb, const struct xt_action_param *par)
 
 #ifdef WITH_CONNTRACK
 	nf_conntrack_put(skb->nfct);
-	skb->nfct     = &nf_conntrack_untracked.ct_general;
+	skb->nfct     = &nf_ct_untracked_get()->ct_general;
 	skb->nfctinfo = IP_CT_NEW;
 	nf_conntrack_get(skb->nfct);
 #endif
diff --git a/net/netfilter/xt_cluster.c b/net/netfilter/xt_cluster.c
index 30b95a1..f4af1bf 100644
--- a/net/netfilter/xt_cluster.c
+++ b/net/netfilter/xt_cluster.c
@@ -120,7 +120,7 @@ xt_cluster_mt(const struct sk_buff *skb, struct xt_action_param *par)
 	if (ct == NULL)
 		return false;
 
-	if (ct == &nf_conntrack_untracked)
+	if (nf_ct_is_untracked(ct))
 		return false;
 
 	if (ct->master)
diff --git a/net/netfilter/xt_conntrack.c b/net/netfilter/xt_conntrack.c
index 39681f1..e536710 100644
--- a/net/netfilter/xt_conntrack.c
+++ b/net/netfilter/xt_conntrack.c
@@ -123,11 +123,12 @@ conntrack_mt(const struct sk_buff *skb, struct xt_action_param *par,
 
 	ct = nf_ct_get(skb, &ctinfo);
 
-	if (ct == &nf_conntrack_untracked)
-		statebit = XT_CONNTRACK_STATE_UNTRACKED;
-	else if (ct != NULL)
-		statebit = XT_CONNTRACK_STATE_BIT(ctinfo);
-	else
+	if (ct) {
+		if (nf_ct_is_untracked(ct))
+			statebit = XT_CONNTRACK_STATE_UNTRACKED;
+		else
+			statebit = XT_CONNTRACK_STATE_BIT(ctinfo);
+	} else
 		statebit = XT_CONNTRACK_STATE_INVALID;
 
 	if (info->match_flags & XT_CONNTRACK_STATE) {
diff --git a/net/netfilter/xt_socket.c b/net/netfilter/xt_socket.c
index 3d54c23..1ca8990 100644
--- a/net/netfilter/xt_socket.c
+++ b/net/netfilter/xt_socket.c
@@ -127,7 +127,7 @@ socket_match(const struct sk_buff *skb, struct xt_action_param *par,
 	 * reply packet of an established SNAT-ted connection. */
 
 	ct = nf_ct_get(skb, &ctinfo);
-	if (ct && (ct != &nf_conntrack_untracked) &&
+	if (ct && !nf_ct_is_untracked(ct) &&
 	    ((iph->protocol != IPPROTO_ICMP &&
 	      ctinfo == IP_CT_IS_REPLY + IP_CT_ESTABLISHED) ||
 	     (iph->protocol == IPPROTO_ICMP &&
diff --git a/net/netfilter/xt_state.c b/net/netfilter/xt_state.c
index e12e053..a507922 100644
--- a/net/netfilter/xt_state.c
+++ b/net/netfilter/xt_state.c
@@ -26,14 +26,16 @@ state_mt(const struct sk_buff *skb, struct xt_action_param *par)
 	const struct xt_state_info *sinfo = par->matchinfo;
 	enum ip_conntrack_info ctinfo;
 	unsigned int statebit;
+	struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
 
-	if (nf_ct_is_untracked(skb))
-		statebit = XT_STATE_UNTRACKED;
-	else if (!nf_ct_get(skb, &ctinfo))
+	if (!ct)
 		statebit = XT_STATE_INVALID;
-	else
-		statebit = XT_STATE_BIT(ctinfo);
-
+	else {
+		if (nf_ct_is_untracked(ct))
+			statebit = XT_STATE_UNTRACKED;
+		else
+			statebit = XT_STATE_BIT(ctinfo);
+	}
 	return (sinfo->statemask & statebit);
 }
 
-- 
1.7.0.4

[PATCH 06/17] netfilter: nf_conntrack: per_cpu untracking

[kaber]

From: Eric Dumazet <eric.dumazet@gmail.com>

NOTRACK makes all cpus share a cache line on nf_conntrack_untracked
twice per packet, slowing down performance.

This patch converts it to a per_cpu variable.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
---
 include/net/netfilter/nf_conntrack.h |    5 +--
 net/netfilter/nf_conntrack_core.c    |   36 ++++++++++++++++++++++++---------
 2 files changed, 28 insertions(+), 13 deletions(-)

diff --git a/include/net/netfilter/nf_conntrack.h b/include/net/netfilter/nf_conntrack.h
index 3bc38c7..84a4b6f 100644
--- a/include/net/netfilter/nf_conntrack.h
+++ b/include/net/netfilter/nf_conntrack.h
@@ -261,11 +261,10 @@ extern s16 (*nf_ct_nat_offset)(const struct nf_conn *ct,
 			       u32 seq);
 
 /* Fake conntrack entry for untracked connections */
+DECLARE_PER_CPU(struct nf_conn, nf_conntrack_untracked);
 static inline struct nf_conn *nf_ct_untracked_get(void)
 {
-	extern struct nf_conn nf_conntrack_untracked;
-
-	return &nf_conntrack_untracked;
+	return &__raw_get_cpu_var(nf_conntrack_untracked);
 }
 extern void nf_ct_untracked_status_or(unsigned long bits);
 
diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c
index 6c1da21..9c66141 100644
--- a/net/netfilter/nf_conntrack_core.c
+++ b/net/netfilter/nf_conntrack_core.c
@@ -62,8 +62,8 @@ EXPORT_SYMBOL_GPL(nf_conntrack_htable_size);
 unsigned int nf_conntrack_max __read_mostly;
 EXPORT_SYMBOL_GPL(nf_conntrack_max);
 
-struct nf_conn nf_conntrack_untracked;
-EXPORT_SYMBOL_GPL(nf_conntrack_untracked);
+DEFINE_PER_CPU(struct nf_conn, nf_conntrack_untracked);
+EXPORT_PER_CPU_SYMBOL(nf_conntrack_untracked);
 
 static int nf_conntrack_hash_rnd_initted;
 static unsigned int nf_conntrack_hash_rnd;
@@ -1183,10 +1183,21 @@ static void nf_ct_release_dying_list(struct net *net)
 	spin_unlock_bh(&nf_conntrack_lock);
 }
 
+static int untrack_refs(void)
+{
+	int cnt = 0, cpu;
+
+	for_each_possible_cpu(cpu) {
+		struct nf_conn *ct = &per_cpu(nf_conntrack_untracked, cpu);
+
+		cnt += atomic_read(&ct->ct_general.use) - 1;
+	}
+	return cnt;
+}
+
 static void nf_conntrack_cleanup_init_net(void)
 {
-	/* wait until all references to nf_conntrack_untracked are dropped */
-	while (atomic_read(&nf_conntrack_untracked.ct_general.use) > 1)
+	while (untrack_refs() > 0)
 		schedule();
 
 	nf_conntrack_helper_fini();
@@ -1323,14 +1334,17 @@ module_param_call(hashsize, nf_conntrack_set_hashsize, param_get_uint,
 
 void nf_ct_untracked_status_or(unsigned long bits)
 {
-	nf_conntrack_untracked.status |= bits;
+	int cpu;
+
+	for_each_possible_cpu(cpu)
+		per_cpu(nf_conntrack_untracked, cpu).status |= bits;
 }
 EXPORT_SYMBOL_GPL(nf_ct_untracked_status_or);
 
 static int nf_conntrack_init_init_net(void)
 {
 	int max_factor = 8;
-	int ret;
+	int ret, cpu;
 
 	/* Idea from tcp.c: use 1/16384 of memory.  On i386: 32MB
 	 * machine has 512 buckets. >= 1GB machines have 16384 buckets. */
@@ -1369,10 +1383,12 @@ static int nf_conntrack_init_init_net(void)
 		goto err_extend;
 #endif
 	/* Set up fake conntrack: to never be deleted, not in any hashes */
-#ifdef CONFIG_NET_NS
-	nf_conntrack_untracked.ct_net = &init_net;
-#endif
-	atomic_set(&nf_conntrack_untracked.ct_general.use, 1);
+	for_each_possible_cpu(cpu) {
+		struct nf_conn *ct = &per_cpu(nf_conntrack_untracked, cpu);
+
+		write_pnet(&ct->ct_net, &init_net);
+		atomic_set(&ct->ct_general.use, 1);
+	}
 	/*  - and look it like as a confirmed connection */
 	nf_ct_untracked_status_or(IPS_CONFIRMED | IPS_UNTRACKED);
 	return 0;
-- 
1.7.0.4

[PATCH 07/17] netfilter: xt_sctp: use WORD_ROUND macro to calculate length of multiple of 4 bytes

[kaber]

From: Shan Wei <shanwei@cn.fujitsu.com>

Use  WORD_ROUND to round an int up to the next multiple of 4.

Signed-off-by: Shan Wei <shanwei@cn.fujitsu.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
---
 net/netfilter/xt_sctp.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/net/netfilter/xt_sctp.c b/net/netfilter/xt_sctp.c
index c04fcf3..ef36a56 100644
--- a/net/netfilter/xt_sctp.c
+++ b/net/netfilter/xt_sctp.c
@@ -3,6 +3,7 @@
 #include <linux/skbuff.h>
 #include <net/ip.h>
 #include <net/ipv6.h>
+#include <net/sctp/sctp.h>
 #include <linux/sctp.h>
 
 #include <linux/netfilter/x_tables.h>
@@ -67,7 +68,7 @@ match_packet(const struct sk_buff *skb,
 			 ++i, offset, sch->type, htons(sch->length),
 			 sch->flags);
 #endif
-		offset += (ntohs(sch->length) + 3) & ~3;
+		offset += WORD_ROUND(ntohs(sch->length));
 
 		pr_debug("skb->len: %d\toffset: %d\n", skb->len, offset);
 
-- 
1.7.0.4

[PATCH 08/17] netfilter: ip_queue: rwlock to spinlock conversion

[kaber]

From: Eric Dumazet <eric.dumazet@gmail.com>

Converts queue_lock rwlock to a spinlock.

(readlocked part can be changed by reads of integer values)

One atomic operation instead of four per ipq_enqueue_packet() call.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
---
 net/ipv4/netfilter/ip_queue.c |   57 ++++++++++++++++++-----------------------
 1 files changed, 25 insertions(+), 32 deletions(-)

diff --git a/net/ipv4/netfilter/ip_queue.c b/net/ipv4/netfilter/ip_queue.c
index a4e5fc5..d2c1311 100644
--- a/net/ipv4/netfilter/ip_queue.c
+++ b/net/ipv4/netfilter/ip_queue.c
@@ -42,7 +42,7 @@ typedef int (*ipq_cmpfn)(struct nf_queue_entry *, unsigned long);
 
 static unsigned char copy_mode __read_mostly = IPQ_COPY_NONE;
 static unsigned int queue_maxlen __read_mostly = IPQ_QMAX_DEFAULT;
-static DEFINE_RWLOCK(queue_lock);
+static DEFINE_SPINLOCK(queue_lock);
 static int peer_pid __read_mostly;
 static unsigned int copy_range __read_mostly;
 static unsigned int queue_total;
@@ -72,10 +72,10 @@ __ipq_set_mode(unsigned char mode, unsigned int range)
 		break;
 
 	case IPQ_COPY_PACKET:
-		copy_mode = mode;
+		if (range > 0xFFFF)
+			range = 0xFFFF;
 		copy_range = range;
-		if (copy_range > 0xFFFF)
-			copy_range = 0xFFFF;
+		copy_mode = mode;
 		break;
 
 	default:
@@ -101,7 +101,7 @@ ipq_find_dequeue_entry(unsigned long id)
 {
 	struct nf_queue_entry *entry = NULL, *i;
 
-	write_lock_bh(&queue_lock);
+	spin_lock_bh(&queue_lock);
 
 	list_for_each_entry(i, &queue_list, list) {
 		if ((unsigned long)i == id) {
@@ -115,7 +115,7 @@ ipq_find_dequeue_entry(unsigned long id)
 		queue_total--;
 	}
 
-	write_unlock_bh(&queue_lock);
+	spin_unlock_bh(&queue_lock);
 	return entry;
 }
 
@@ -136,9 +136,9 @@ __ipq_flush(ipq_cmpfn cmpfn, unsigned long data)
 static void
 ipq_flush(ipq_cmpfn cmpfn, unsigned long data)
 {
-	write_lock_bh(&queue_lock);
+	spin_lock_bh(&queue_lock);
 	__ipq_flush(cmpfn, data);
-	write_unlock_bh(&queue_lock);
+	spin_unlock_bh(&queue_lock);
 }
 
 static struct sk_buff *
@@ -152,9 +152,7 @@ ipq_build_packet_message(struct nf_queue_entry *entry, int *errp)
 	struct nlmsghdr *nlh;
 	struct timeval tv;
 
-	read_lock_bh(&queue_lock);
-
-	switch (copy_mode) {
+	switch (ACCESS_ONCE(copy_mode)) {
 	case IPQ_COPY_META:
 	case IPQ_COPY_NONE:
 		size = NLMSG_SPACE(sizeof(*pmsg));
@@ -162,26 +160,21 @@ ipq_build_packet_message(struct nf_queue_entry *entry, int *errp)
 
 	case IPQ_COPY_PACKET:
 		if (entry->skb->ip_summed == CHECKSUM_PARTIAL &&
-		    (*errp = skb_checksum_help(entry->skb))) {
-			read_unlock_bh(&queue_lock);
+		    (*errp = skb_checksum_help(entry->skb)))
 			return NULL;
-		}
-		if (copy_range == 0 || copy_range > entry->skb->len)
+
+		data_len = ACCESS_ONCE(copy_range);
+		if (data_len == 0 || data_len > entry->skb->len)
 			data_len = entry->skb->len;
-		else
-			data_len = copy_range;
 
 		size = NLMSG_SPACE(sizeof(*pmsg) + data_len);
 		break;
 
 	default:
 		*errp = -EINVAL;
-		read_unlock_bh(&queue_lock);
 		return NULL;
 	}
 
-	read_unlock_bh(&queue_lock);
-
 	skb = alloc_skb(size, GFP_ATOMIC);
 	if (!skb)
 		goto nlmsg_failure;
@@ -242,7 +235,7 @@ ipq_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum)
 	if (nskb == NULL)
 		return status;
 
-	write_lock_bh(&queue_lock);
+	spin_lock_bh(&queue_lock);
 
 	if (!peer_pid)
 		goto err_out_free_nskb;
@@ -266,14 +259,14 @@ ipq_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum)
 
 	__ipq_enqueue_entry(entry);
 
-	write_unlock_bh(&queue_lock);
+	spin_unlock_bh(&queue_lock);
 	return status;
 
 err_out_free_nskb:
 	kfree_skb(nskb);
 
 err_out_unlock:
-	write_unlock_bh(&queue_lock);
+	spin_unlock_bh(&queue_lock);
 	return status;
 }
 
@@ -342,9 +335,9 @@ ipq_set_mode(unsigned char mode, unsigned int range)
 {
 	int status;
 
-	write_lock_bh(&queue_lock);
+	spin_lock_bh(&queue_lock);
 	status = __ipq_set_mode(mode, range);
-	write_unlock_bh(&queue_lock);
+	spin_unlock_bh(&queue_lock);
 	return status;
 }
 
@@ -440,11 +433,11 @@ __ipq_rcv_skb(struct sk_buff *skb)
 	if (security_netlink_recv(skb, CAP_NET_ADMIN))
 		RCV_SKB_FAIL(-EPERM);
 
-	write_lock_bh(&queue_lock);
+	spin_lock_bh(&queue_lock);
 
 	if (peer_pid) {
 		if (peer_pid != pid) {
-			write_unlock_bh(&queue_lock);
+			spin_unlock_bh(&queue_lock);
 			RCV_SKB_FAIL(-EBUSY);
 		}
 	} else {
@@ -452,7 +445,7 @@ __ipq_rcv_skb(struct sk_buff *skb)
 		peer_pid = pid;
 	}
 
-	write_unlock_bh(&queue_lock);
+	spin_unlock_bh(&queue_lock);
 
 	status = ipq_receive_peer(NLMSG_DATA(nlh), type,
 				  nlmsglen - NLMSG_LENGTH(0));
@@ -497,10 +490,10 @@ ipq_rcv_nl_event(struct notifier_block *this,
 	struct netlink_notify *n = ptr;
 
 	if (event == NETLINK_URELEASE && n->protocol == NETLINK_FIREWALL) {
-		write_lock_bh(&queue_lock);
+		spin_lock_bh(&queue_lock);
 		if ((net_eq(n->net, &init_net)) && (n->pid == peer_pid))
 			__ipq_reset();
-		write_unlock_bh(&queue_lock);
+		spin_unlock_bh(&queue_lock);
 	}
 	return NOTIFY_DONE;
 }
@@ -527,7 +520,7 @@ static ctl_table ipq_table[] = {
 #ifdef CONFIG_PROC_FS
 static int ip_queue_show(struct seq_file *m, void *v)
 {
-	read_lock_bh(&queue_lock);
+	spin_lock_bh(&queue_lock);
 
 	seq_printf(m,
 		      "Peer PID          : %d\n"
@@ -545,7 +538,7 @@ static int ip_queue_show(struct seq_file *m, void *v)
 		      queue_dropped,
 		      queue_user_dropped);
 
-	read_unlock_bh(&queue_lock);
+	spin_unlock_bh(&queue_lock);
 	return 0;
 }
 
-- 
1.7.0.4

[PATCH 09/17] netfilter: ip6_queue: rwlock to spinlock conversion

[kaber]

From: Eric Dumazet <eric.dumazet@gmail.com>

Converts queue_lock rwlock to a spinlock.

(readlocked part can be changed by reads of integer values)

One atomic operation instead of four per ipq_enqueue_packet() call.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
---
 net/ipv6/netfilter/ip6_queue.c |   57 +++++++++++++++++----------------------
 1 files changed, 25 insertions(+), 32 deletions(-)

diff --git a/net/ipv6/netfilter/ip6_queue.c b/net/ipv6/netfilter/ip6_queue.c
index 8c20174..413ab07 100644
--- a/net/ipv6/netfilter/ip6_queue.c
+++ b/net/ipv6/netfilter/ip6_queue.c
@@ -43,7 +43,7 @@ typedef int (*ipq_cmpfn)(struct nf_queue_entry *, unsigned long);
 
 static unsigned char copy_mode __read_mostly = IPQ_COPY_NONE;
 static unsigned int queue_maxlen __read_mostly = IPQ_QMAX_DEFAULT;
-static DEFINE_RWLOCK(queue_lock);
+static DEFINE_SPINLOCK(queue_lock);
 static int peer_pid __read_mostly;
 static unsigned int copy_range __read_mostly;
 static unsigned int queue_total;
@@ -73,10 +73,10 @@ __ipq_set_mode(unsigned char mode, unsigned int range)
 		break;
 
 	case IPQ_COPY_PACKET:
-		copy_mode = mode;
+		if (range > 0xFFFF)
+			range = 0xFFFF;
 		copy_range = range;
-		if (copy_range > 0xFFFF)
-			copy_range = 0xFFFF;
+		copy_mode = mode;
 		break;
 
 	default:
@@ -102,7 +102,7 @@ ipq_find_dequeue_entry(unsigned long id)
 {
 	struct nf_queue_entry *entry = NULL, *i;
 
-	write_lock_bh(&queue_lock);
+	spin_lock_bh(&queue_lock);
 
 	list_for_each_entry(i, &queue_list, list) {
 		if ((unsigned long)i == id) {
@@ -116,7 +116,7 @@ ipq_find_dequeue_entry(unsigned long id)
 		queue_total--;
 	}
 
-	write_unlock_bh(&queue_lock);
+	spin_unlock_bh(&queue_lock);
 	return entry;
 }
 
@@ -137,9 +137,9 @@ __ipq_flush(ipq_cmpfn cmpfn, unsigned long data)
 static void
 ipq_flush(ipq_cmpfn cmpfn, unsigned long data)
 {
-	write_lock_bh(&queue_lock);
+	spin_lock_bh(&queue_lock);
 	__ipq_flush(cmpfn, data);
-	write_unlock_bh(&queue_lock);
+	spin_unlock_bh(&queue_lock);
 }
 
 static struct sk_buff *
@@ -153,9 +153,7 @@ ipq_build_packet_message(struct nf_queue_entry *entry, int *errp)
 	struct nlmsghdr *nlh;
 	struct timeval tv;
 
-	read_lock_bh(&queue_lock);
-
-	switch (copy_mode) {
+	switch (ACCESS_ONCE(copy_mode)) {
 	case IPQ_COPY_META:
 	case IPQ_COPY_NONE:
 		size = NLMSG_SPACE(sizeof(*pmsg));
@@ -163,26 +161,21 @@ ipq_build_packet_message(struct nf_queue_entry *entry, int *errp)
 
 	case IPQ_COPY_PACKET:
 		if (entry->skb->ip_summed == CHECKSUM_PARTIAL &&
-		    (*errp = skb_checksum_help(entry->skb))) {
-			read_unlock_bh(&queue_lock);
+		    (*errp = skb_checksum_help(entry->skb)))
 			return NULL;
-		}
-		if (copy_range == 0 || copy_range > entry->skb->len)
+
+		data_len = ACCESS_ONCE(copy_range);
+		if (data_len == 0 || data_len > entry->skb->len)
 			data_len = entry->skb->len;
-		else
-			data_len = copy_range;
 
 		size = NLMSG_SPACE(sizeof(*pmsg) + data_len);
 		break;
 
 	default:
 		*errp = -EINVAL;
-		read_unlock_bh(&queue_lock);
 		return NULL;
 	}
 
-	read_unlock_bh(&queue_lock);
-
 	skb = alloc_skb(size, GFP_ATOMIC);
 	if (!skb)
 		goto nlmsg_failure;
@@ -242,7 +235,7 @@ ipq_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum)
 	if (nskb == NULL)
 		return status;
 
-	write_lock_bh(&queue_lock);
+	spin_lock_bh(&queue_lock);
 
 	if (!peer_pid)
 		goto err_out_free_nskb;
@@ -266,14 +259,14 @@ ipq_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum)
 
 	__ipq_enqueue_entry(entry);
 
-	write_unlock_bh(&queue_lock);
+	spin_unlock_bh(&queue_lock);
 	return status;
 
 err_out_free_nskb:
 	kfree_skb(nskb);
 
 err_out_unlock:
-	write_unlock_bh(&queue_lock);
+	spin_unlock_bh(&queue_lock);
 	return status;
 }
 
@@ -342,9 +335,9 @@ ipq_set_mode(unsigned char mode, unsigned int range)
 {
 	int status;
 
-	write_lock_bh(&queue_lock);
+	spin_lock_bh(&queue_lock);
 	status = __ipq_set_mode(mode, range);
-	write_unlock_bh(&queue_lock);
+	spin_unlock_bh(&queue_lock);
 	return status;
 }
 
@@ -441,11 +434,11 @@ __ipq_rcv_skb(struct sk_buff *skb)
 	if (security_netlink_recv(skb, CAP_NET_ADMIN))
 		RCV_SKB_FAIL(-EPERM);
 
-	write_lock_bh(&queue_lock);
+	spin_lock_bh(&queue_lock);
 
 	if (peer_pid) {
 		if (peer_pid != pid) {
-			write_unlock_bh(&queue_lock);
+			spin_unlock_bh(&queue_lock);
 			RCV_SKB_FAIL(-EBUSY);
 		}
 	} else {
@@ -453,7 +446,7 @@ __ipq_rcv_skb(struct sk_buff *skb)
 		peer_pid = pid;
 	}
 
-	write_unlock_bh(&queue_lock);
+	spin_unlock_bh(&queue_lock);
 
 	status = ipq_receive_peer(NLMSG_DATA(nlh), type,
 				  nlmsglen - NLMSG_LENGTH(0));
@@ -498,10 +491,10 @@ ipq_rcv_nl_event(struct notifier_block *this,
 	struct netlink_notify *n = ptr;
 
 	if (event == NETLINK_URELEASE && n->protocol == NETLINK_IP6_FW) {
-		write_lock_bh(&queue_lock);
+		spin_lock_bh(&queue_lock);
 		if ((net_eq(n->net, &init_net)) && (n->pid == peer_pid))
 			__ipq_reset();
-		write_unlock_bh(&queue_lock);
+		spin_unlock_bh(&queue_lock);
 	}
 	return NOTIFY_DONE;
 }
@@ -528,7 +521,7 @@ static ctl_table ipq_table[] = {
 #ifdef CONFIG_PROC_FS
 static int ip6_queue_show(struct seq_file *m, void *v)
 {
-	read_lock_bh(&queue_lock);
+	spin_lock_bh(&queue_lock);
 
 	seq_printf(m,
 		      "Peer PID          : %d\n"
@@ -546,7 +539,7 @@ static int ip6_queue_show(struct seq_file *m, void *v)
 		      queue_dropped,
 		      queue_user_dropped);
 
-	read_unlock_bh(&queue_lock);
+	spin_unlock_bh(&queue_lock);
 	return 0;
 }
 
-- 
1.7.0.4

[PATCH 10/17] netfilter: nfnetlink_queue: some optimizations

[kaber]

From: Eric Dumazet <eric.dumazet@gmail.com>

- Use an atomic_t for id_sequence to avoid a spin_lock/spin_unlock pair

- Group highly modified struct nfqnl_instance fields together

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
---
 net/netfilter/nfnetlink_queue.c |   33 ++++++++++++++-------------------
 1 files changed, 14 insertions(+), 19 deletions(-)

diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
index 12e1ab3..d05605b 100644
--- a/net/netfilter/nfnetlink_queue.c
+++ b/net/netfilter/nfnetlink_queue.c
@@ -46,17 +46,19 @@ struct nfqnl_instance {
 	int peer_pid;
 	unsigned int queue_maxlen;
 	unsigned int copy_range;
-	unsigned int queue_total;
 	unsigned int queue_dropped;
 	unsigned int queue_user_dropped;
 
-	unsigned int id_sequence;		/* 'sequence' of pkt ids */
 
 	u_int16_t queue_num;			/* number of this queue */
 	u_int8_t copy_mode;
-
-	spinlock_t lock;
-
+/*
+ * Following fields are dirtied for each queued packet,
+ * keep them in same cache line if possible.
+ */
+	spinlock_t	lock;
+	unsigned int	queue_total;
+	atomic_t	id_sequence;		/* 'sequence' of pkt ids */
 	struct list_head queue_list;		/* packets in queue */
 };
 
@@ -238,32 +240,24 @@ nfqnl_build_packet_message(struct nfqnl_instance *queue,
 
 	outdev = entry->outdev;
 
-	spin_lock_bh(&queue->lock);
-
-	switch ((enum nfqnl_config_mode)queue->copy_mode) {
+	switch ((enum nfqnl_config_mode)ACCESS_ONCE(queue->copy_mode)) {
 	case NFQNL_COPY_META:
 	case NFQNL_COPY_NONE:
 		break;
 
 	case NFQNL_COPY_PACKET:
 		if (entskb->ip_summed == CHECKSUM_PARTIAL &&
-		    skb_checksum_help(entskb)) {
-			spin_unlock_bh(&queue->lock);
+		    skb_checksum_help(entskb))
 			return NULL;
-		}
-		if (queue->copy_range == 0
-		    || queue->copy_range > entskb->len)
+
+		data_len = ACCESS_ONCE(queue->copy_range);
+		if (data_len == 0 || data_len > entskb->len)
 			data_len = entskb->len;
-		else
-			data_len = queue->copy_range;
 
 		size += nla_total_size(data_len);
 		break;
 	}
 
-	entry->id = queue->id_sequence++;
-
-	spin_unlock_bh(&queue->lock);
 
 	skb = alloc_skb(size, GFP_ATOMIC);
 	if (!skb)
@@ -278,6 +272,7 @@ nfqnl_build_packet_message(struct nfqnl_instance *queue,
 	nfmsg->version = NFNETLINK_V0;
 	nfmsg->res_id = htons(queue->queue_num);
 
+	entry->id = atomic_inc_return(&queue->id_sequence);
 	pmsg.packet_id 		= htonl(entry->id);
 	pmsg.hw_protocol	= entskb->protocol;
 	pmsg.hook		= entry->hook;
@@ -866,7 +861,7 @@ static int seq_show(struct seq_file *s, void *v)
 			  inst->peer_pid, inst->queue_total,
 			  inst->copy_mode, inst->copy_range,
 			  inst->queue_dropped, inst->queue_user_dropped,
-			  inst->id_sequence, 1);
+			  atomic_read(&inst->id_sequence), 1);
 }
 
 static const struct seq_operations nfqnl_seq_ops = {
-- 
1.7.0.4

[PATCH 11/17] netfilter: nfnetlink_log: RCU conversion

[kaber]

From: Eric Dumazet <eric.dumazet@gmail.com>

- instances_lock becomes a spinlock
- lockless lookups

While nfnetlink_log probably not performance critical, using less
rwlocks in our code is always welcomed...

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
---
 net/netfilter/nfnetlink_log.c |   49 ++++++++++++++++++++++------------------
 1 files changed, 27 insertions(+), 22 deletions(-)

diff --git a/net/netfilter/nfnetlink_log.c b/net/netfilter/nfnetlink_log.c
index fc9a211..8ec23ec 100644
--- a/net/netfilter/nfnetlink_log.c
+++ b/net/netfilter/nfnetlink_log.c
@@ -66,9 +66,10 @@ struct nfulnl_instance {
 	u_int16_t group_num;		/* number of this queue */
 	u_int16_t flags;
 	u_int8_t copy_mode;
+	struct rcu_head rcu;
 };
 
-static DEFINE_RWLOCK(instances_lock);
+static DEFINE_SPINLOCK(instances_lock);
 static atomic_t global_seq;
 
 #define INSTANCE_BUCKETS	16
@@ -88,7 +89,7 @@ __instance_lookup(u_int16_t group_num)
 	struct nfulnl_instance *inst;
 
 	head = &instance_table[instance_hashfn(group_num)];
-	hlist_for_each_entry(inst, pos, head, hlist) {
+	hlist_for_each_entry_rcu(inst, pos, head, hlist) {
 		if (inst->group_num == group_num)
 			return inst;
 	}
@@ -106,22 +107,26 @@ instance_lookup_get(u_int16_t group_num)
 {
 	struct nfulnl_instance *inst;
 
-	read_lock_bh(&instances_lock);
+	rcu_read_lock_bh();
 	inst = __instance_lookup(group_num);
 	if (inst)
 		instance_get(inst);
-	read_unlock_bh(&instances_lock);
+	rcu_read_unlock_bh();
 
 	return inst;
 }
 
+static void nfulnl_instance_free_rcu(struct rcu_head *head)
+{
+	kfree(container_of(head, struct nfulnl_instance, rcu));
+	module_put(THIS_MODULE);
+}
+
 static void
 instance_put(struct nfulnl_instance *inst)
 {
-	if (inst && atomic_dec_and_test(&inst->use)) {
-		kfree(inst);
-		module_put(THIS_MODULE);
-	}
+	if (inst && atomic_dec_and_test(&inst->use))
+		call_rcu_bh(&inst->rcu, nfulnl_instance_free_rcu);
 }
 
 static void nfulnl_timer(unsigned long data);
@@ -132,7 +137,7 @@ instance_create(u_int16_t group_num, int pid)
 	struct nfulnl_instance *inst;
 	int err;
 
-	write_lock_bh(&instances_lock);
+	spin_lock_bh(&instances_lock);
 	if (__instance_lookup(group_num)) {
 		err = -EEXIST;
 		goto out_unlock;
@@ -169,12 +174,12 @@ instance_create(u_int16_t group_num, int pid)
 	hlist_add_head(&inst->hlist,
 		       &instance_table[instance_hashfn(group_num)]);
 
-	write_unlock_bh(&instances_lock);
+	spin_unlock_bh(&instances_lock);
 
 	return inst;
 
 out_unlock:
-	write_unlock_bh(&instances_lock);
+	spin_unlock_bh(&instances_lock);
 	return ERR_PTR(err);
 }
 
@@ -200,9 +205,9 @@ __instance_destroy(struct nfulnl_instance *inst)
 static inline void
 instance_destroy(struct nfulnl_instance *inst)
 {
-	write_lock_bh(&instances_lock);
+	spin_lock_bh(&instances_lock);
 	__instance_destroy(inst);
-	write_unlock_bh(&instances_lock);
+	spin_unlock_bh(&instances_lock);
 }
 
 static int
@@ -672,7 +677,7 @@ nfulnl_rcv_nl_event(struct notifier_block *this,
 		int i;
 
 		/* destroy all instances for this pid */
-		write_lock_bh(&instances_lock);
+		spin_lock_bh(&instances_lock);
 		for  (i = 0; i < INSTANCE_BUCKETS; i++) {
 			struct hlist_node *tmp, *t2;
 			struct nfulnl_instance *inst;
@@ -684,7 +689,7 @@ nfulnl_rcv_nl_event(struct notifier_block *this,
 					__instance_destroy(inst);
 			}
 		}
-		write_unlock_bh(&instances_lock);
+		spin_unlock_bh(&instances_lock);
 	}
 	return NOTIFY_DONE;
 }
@@ -861,19 +866,19 @@ static struct hlist_node *get_first(struct iter_state *st)
 
 	for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) {
 		if (!hlist_empty(&instance_table[st->bucket]))
-			return instance_table[st->bucket].first;
+			return rcu_dereference_bh(instance_table[st->bucket].first);
 	}
 	return NULL;
 }
 
 static struct hlist_node *get_next(struct iter_state *st, struct hlist_node *h)
 {
-	h = h->next;
+	h = rcu_dereference_bh(h->next);
 	while (!h) {
 		if (++st->bucket >= INSTANCE_BUCKETS)
 			return NULL;
 
-		h = instance_table[st->bucket].first;
+		h = rcu_dereference_bh(instance_table[st->bucket].first);
 	}
 	return h;
 }
@@ -890,9 +895,9 @@ static struct hlist_node *get_idx(struct iter_state *st, loff_t pos)
 }
 
 static void *seq_start(struct seq_file *seq, loff_t *pos)
-	__acquires(instances_lock)
+	__acquires(rcu_bh)
 {
-	read_lock_bh(&instances_lock);
+	rcu_read_lock_bh();
 	return get_idx(seq->private, *pos);
 }
 
@@ -903,9 +908,9 @@ static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
 }
 
 static void seq_stop(struct seq_file *s, void *v)
-	__releases(instances_lock)
+	__releases(rcu_bh)
 {
-	read_unlock_bh(&instances_lock);
+	rcu_read_unlock_bh();
 }
 
 static int seq_show(struct seq_file *s, void *v)
-- 
1.7.0.4

[PATCH 12/17] netfilter: nfnetlink_log: RCU conversion, part 2

[kaber]

From: Eric Dumazet <eric.dumazet@gmail.com>

- must use atomic_inc_not_zero() in instance_lookup_get()

- must use hlist_add_head_rcu() instead of hlist_add_head()

- must use hlist_del_rcu() instead of hlist_del()

- Introduce NFULNL_COPY_DISABLED to stop lockless reader from using an
instance, before we do final instance_put() on it.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
---
 include/linux/netfilter/nfnetlink_log.h |    1 +
 net/netfilter/nfnetlink_log.c           |   18 ++++++++++++------
 2 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/include/linux/netfilter/nfnetlink_log.h b/include/linux/netfilter/nfnetlink_log.h
index d3bab7a..1d0b84a 100644
--- a/include/linux/netfilter/nfnetlink_log.h
+++ b/include/linux/netfilter/nfnetlink_log.h
@@ -89,6 +89,7 @@ enum nfulnl_attr_config {
 #define NFULNL_COPY_NONE	0x00
 #define NFULNL_COPY_META	0x01
 #define NFULNL_COPY_PACKET	0x02
+#define NFULNL_COPY_DISABLED	0x03
 
 #define NFULNL_CFG_F_SEQ	0x0001
 #define NFULNL_CFG_F_SEQ_GLOBAL	0x0002
diff --git a/net/netfilter/nfnetlink_log.c b/net/netfilter/nfnetlink_log.c
index 8ec23ec..fb86a51 100644
--- a/net/netfilter/nfnetlink_log.c
+++ b/net/netfilter/nfnetlink_log.c
@@ -109,8 +109,8 @@ instance_lookup_get(u_int16_t group_num)
 
 	rcu_read_lock_bh();
 	inst = __instance_lookup(group_num);
-	if (inst)
-		instance_get(inst);
+	if (inst && !atomic_inc_not_zero(&inst->use))
+		inst = NULL;
 	rcu_read_unlock_bh();
 
 	return inst;
@@ -171,7 +171,7 @@ instance_create(u_int16_t group_num, int pid)
 	inst->copy_mode 	= NFULNL_COPY_PACKET;
 	inst->copy_range 	= NFULNL_COPY_RANGE_MAX;
 
-	hlist_add_head(&inst->hlist,
+	hlist_add_head_rcu(&inst->hlist,
 		       &instance_table[instance_hashfn(group_num)]);
 
 	spin_unlock_bh(&instances_lock);
@@ -185,18 +185,23 @@ out_unlock:
 
 static void __nfulnl_flush(struct nfulnl_instance *inst);
 
+/* called with BH disabled */
 static void
 __instance_destroy(struct nfulnl_instance *inst)
 {
 	/* first pull it out of the global list */
-	hlist_del(&inst->hlist);
+	hlist_del_rcu(&inst->hlist);
 
 	/* then flush all pending packets from skb */
 
-	spin_lock_bh(&inst->lock);
+	spin_lock(&inst->lock);
+
+	/* lockless readers wont be able to use us */
+	inst->copy_mode = NFULNL_COPY_DISABLED;
+
 	if (inst->skb)
 		__nfulnl_flush(inst);
-	spin_unlock_bh(&inst->lock);
+	spin_unlock(&inst->lock);
 
 	/* and finally put the refcount */
 	instance_put(inst);
@@ -624,6 +629,7 @@ nfulnl_log_packet(u_int8_t pf,
 		size += nla_total_size(data_len);
 		break;
 
+	case NFULNL_COPY_DISABLED:
 	default:
 		goto unlock_and_release;
 	}
-- 
1.7.0.4

[PATCH 13/17] netfilter: kill redundant check code in which setting ip_summed value

[kaber]

From: Shan Wei <shanwei@cn.fujitsu.com>

If the returned csum value is 0, We has set ip_summed with
CHECKSUM_UNNECESSARY flag in __skb_checksum_complete_head().

So this patch kills the check and changes to return to upper
caller directly.

Signed-off-by: Shan Wei <shanwei@cn.fujitsu.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
---
 net/ipv4/netfilter.c |    4 +---
 net/ipv6/netfilter.c |    4 +---
 2 files changed, 2 insertions(+), 6 deletions(-)

diff --git a/net/ipv4/netfilter.c b/net/ipv4/netfilter.c
index 07de855..acd1ea8 100644
--- a/net/ipv4/netfilter.c
+++ b/net/ipv4/netfilter.c
@@ -212,9 +212,7 @@ static __sum16 nf_ip_checksum_partial(struct sk_buff *skb, unsigned int hook,
 		skb->csum = csum_tcpudp_nofold(iph->saddr, iph->daddr, protocol,
 					       skb->len - dataoff, 0);
 		skb->ip_summed = CHECKSUM_NONE;
-		csum = __skb_checksum_complete_head(skb, dataoff + len);
-		if (!csum)
-			skb->ip_summed = CHECKSUM_UNNECESSARY;
+		return __skb_checksum_complete_head(skb, dataoff + len);
 	}
 	return csum;
 }
diff --git a/net/ipv6/netfilter.c b/net/ipv6/netfilter.c
index a74951c..7155b24 100644
--- a/net/ipv6/netfilter.c
+++ b/net/ipv6/netfilter.c
@@ -151,9 +151,7 @@ static __sum16 nf_ip6_checksum_partial(struct sk_buff *skb, unsigned int hook,
 							 protocol,
 							 csum_sub(0, hsum)));
 		skb->ip_summed = CHECKSUM_NONE;
-		csum = __skb_checksum_complete_head(skb, dataoff + len);
-		if (!csum)
-			skb->ip_summed = CHECKSUM_UNNECESSARY;
+		return __skb_checksum_complete_head(skb, dataoff + len);
 	}
 	return csum;
 };
-- 
1.7.0.4

[PATCH 14/17] netfilter: defrag: remove one redundant atomic ops

[kaber]

From: Shan Wei <shanwei@cn.fujitsu.com>

Instead of doing one atomic operation per frag, we can factorize them.
Reported from Eric Dumazet.

Signed-off-by: Shan Wei <shanwei@cn.fujitsu.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
---
 net/ipv6/netfilter/nf_conntrack_reasm.c |    3 +--
 1 files changed, 1 insertions(+), 2 deletions(-)

diff --git a/net/ipv6/netfilter/nf_conntrack_reasm.c b/net/ipv6/netfilter/nf_conntrack_reasm.c
index 6fb8901..bc5b86d 100644
--- a/net/ipv6/netfilter/nf_conntrack_reasm.c
+++ b/net/ipv6/netfilter/nf_conntrack_reasm.c
@@ -442,7 +442,6 @@ nf_ct_frag6_reasm(struct nf_ct_frag6_queue *fq, struct net_device *dev)
 	skb_shinfo(head)->frag_list = head->next;
 	skb_reset_transport_header(head);
 	skb_push(head, head->data - skb_network_header(head));
-	atomic_sub(head->truesize, &nf_init_frags.mem);
 
 	for (fp=head->next; fp; fp = fp->next) {
 		head->data_len += fp->len;
@@ -452,8 +451,8 @@ nf_ct_frag6_reasm(struct nf_ct_frag6_queue *fq, struct net_device *dev)
 		else if (head->ip_summed == CHECKSUM_COMPLETE)
 			head->csum = csum_add(head->csum, fp->csum);
 		head->truesize += fp->truesize;
-		atomic_sub(fp->truesize, &nf_init_frags.mem);
 	}
+	atomic_sub(head->truesize, &nf_init_frags.mem);
 
 	head->next = NULL;
 	head->dev = dev;
-- 
1.7.0.4

[PATCH 15/17] netfilter: defrag: kill unused work parameter of frag_kfree_skb()

[kaber]

From: Shan Wei <shanwei@cn.fujitsu.com>

The parameter (work) is unused, remove it.
Reported from Eric Dumazet.

Signed-off-by: Shan Wei <shanwei@cn.fujitsu.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
---
 net/ipv6/netfilter/nf_conntrack_reasm.c |    6 ++----
 1 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/net/ipv6/netfilter/nf_conntrack_reasm.c b/net/ipv6/netfilter/nf_conntrack_reasm.c
index bc5b86d..9254008 100644
--- a/net/ipv6/netfilter/nf_conntrack_reasm.c
+++ b/net/ipv6/netfilter/nf_conntrack_reasm.c
@@ -114,10 +114,8 @@ static void nf_skb_free(struct sk_buff *skb)
 }
 
 /* Memory Tracking Functions. */
-static inline void frag_kfree_skb(struct sk_buff *skb, unsigned int *work)
+static void frag_kfree_skb(struct sk_buff *skb)
 {
-	if (work)
-		*work -= skb->truesize;
 	atomic_sub(skb->truesize, &nf_init_frags.mem);
 	nf_skb_free(skb);
 	kfree_skb(skb);
@@ -335,7 +333,7 @@ static int nf_ct_frag6_queue(struct nf_ct_frag6_queue *fq, struct sk_buff *skb,
 				fq->q.fragments = next;
 
 			fq->q.meat -= free_it->len;
-			frag_kfree_skb(free_it, NULL);
+			frag_kfree_skb(free_it);
 		}
 	}
 
-- 
1.7.0.4

[PATCH 16/17] netfilter: CLUSTERIP: RCU conversion

[kaber]

From: Eric Dumazet <eric.dumazet@gmail.com>

- clusterip_lock becomes a spinlock
- lockless lookups
- kfree() deferred after RCU grace period
- rcu_barrier_bh() inserted in clusterip_tg_exit()

v2)
- As Patrick pointed out, we use atomic_inc_not_zero() in
clusterip_config_find_get().
- list_add_rcu() and list_del_rcu() variants are used.
- atomic_dec_and_lock() used in clusterip_config_entry_put()

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
---
 net/ipv4/netfilter/ipt_CLUSTERIP.c |   48 +++++++++++++++++++++--------------
 1 files changed, 29 insertions(+), 19 deletions(-)

diff --git a/net/ipv4/netfilter/ipt_CLUSTERIP.c b/net/ipv4/netfilter/ipt_CLUSTERIP.c
index f91c94b..64d0875 100644
--- a/net/ipv4/netfilter/ipt_CLUSTERIP.c
+++ b/net/ipv4/netfilter/ipt_CLUSTERIP.c
@@ -53,12 +53,13 @@ struct clusterip_config {
 #endif
 	enum clusterip_hashmode hash_mode;	/* which hashing mode */
 	u_int32_t hash_initval;			/* hash initialization */
+	struct rcu_head rcu;
 };
 
 static LIST_HEAD(clusterip_configs);
 
 /* clusterip_lock protects the clusterip_configs list */
-static DEFINE_RWLOCK(clusterip_lock);
+static DEFINE_SPINLOCK(clusterip_lock);
 
 #ifdef CONFIG_PROC_FS
 static const struct file_operations clusterip_proc_fops;
@@ -71,11 +72,17 @@ clusterip_config_get(struct clusterip_config *c)
 	atomic_inc(&c->refcount);
 }
 
+
+static void clusterip_config_rcu_free(struct rcu_head *head)
+{
+	kfree(container_of(head, struct clusterip_config, rcu));
+}
+
 static inline void
 clusterip_config_put(struct clusterip_config *c)
 {
 	if (atomic_dec_and_test(&c->refcount))
-		kfree(c);
+		call_rcu_bh(&c->rcu, clusterip_config_rcu_free);
 }
 
 /* decrease the count of entries using/referencing this config.  If last
@@ -84,10 +91,11 @@ clusterip_config_put(struct clusterip_config *c)
 static inline void
 clusterip_config_entry_put(struct clusterip_config *c)
 {
-	write_lock_bh(&clusterip_lock);
-	if (atomic_dec_and_test(&c->entries)) {
-		list_del(&c->list);
-		write_unlock_bh(&clusterip_lock);
+	local_bh_disable();
+	if (atomic_dec_and_lock(&c->entries, &clusterip_lock)) {
+		list_del_rcu(&c->list);
+		spin_unlock(&clusterip_lock);
+		local_bh_enable();
 
 		dev_mc_del(c->dev, c->clustermac);
 		dev_put(c->dev);
@@ -100,7 +108,7 @@ clusterip_config_entry_put(struct clusterip_config *c)
 #endif
 		return;
 	}
-	write_unlock_bh(&clusterip_lock);
+	local_bh_enable();
 }
 
 static struct clusterip_config *
@@ -108,7 +116,7 @@ __clusterip_config_find(__be32 clusterip)
 {
 	struct clusterip_config *c;
 
-	list_for_each_entry(c, &clusterip_configs, list) {
+	list_for_each_entry_rcu(c, &clusterip_configs, list) {
 		if (c->clusterip == clusterip)
 			return c;
 	}
@@ -121,16 +129,15 @@ clusterip_config_find_get(__be32 clusterip, int entry)
 {
 	struct clusterip_config *c;
 
-	read_lock_bh(&clusterip_lock);
+	rcu_read_lock_bh();
 	c = __clusterip_config_find(clusterip);
-	if (!c) {
-		read_unlock_bh(&clusterip_lock);
-		return NULL;
+	if (c) {
+		if (unlikely(!atomic_inc_not_zero(&c->refcount)))
+			c = NULL;
+		else if (entry)
+			atomic_inc(&c->entries);
 	}
-	atomic_inc(&c->refcount);
-	if (entry)
-		atomic_inc(&c->entries);
-	read_unlock_bh(&clusterip_lock);
+	rcu_read_unlock_bh();
 
 	return c;
 }
@@ -181,9 +188,9 @@ clusterip_config_init(const struct ipt_clusterip_tgt_info *i, __be32 ip,
 	}
 #endif
 
-	write_lock_bh(&clusterip_lock);
-	list_add(&c->list, &clusterip_configs);
-	write_unlock_bh(&clusterip_lock);
+	spin_lock_bh(&clusterip_lock);
+	list_add_rcu(&c->list, &clusterip_configs);
+	spin_unlock_bh(&clusterip_lock);
 
 	return c;
 }
@@ -733,6 +740,9 @@ static void __exit clusterip_tg_exit(void)
 #endif
 	nf_unregister_hook(&cip_arp_ops);
 	xt_unregister_target(&clusterip_tg_reg);
+
+	/* Wait for completion of call_rcu_bh()'s (clusterip_config_rcu_free) */
+	rcu_barrier_bh();
 }
 
 module_init(clusterip_tg_init);
-- 
1.7.0.4

[PATCH 17/17] netfilter: xtables: idletimer target implementation

[kaber]

From: Luciano Coelho <luciano.coelho@nokia.com>

This patch implements an idletimer Xtables target that can be used to
identify when interfaces have been idle for a certain period of time.

Timers are identified by labels and are created when a rule is set with a new
label.  The rules also take a timeout value (in seconds) as an option.  If
more than one rule uses the same timer label, the timer will be restarted
whenever any of the rules get a hit.

One entry for each timer is created in sysfs.  This attribute contains the
timer remaining for the timer to expire.  The attributes are located under
the xt_idletimer class:

/sys/class/xt_idletimer/timers/<label>

When the timer expires, the target module sends a sysfs notification to the
userspace, which can then decide what to do (eg. disconnect to save power).

Cc: Timo Teras <timo.teras@iki.fi>
Signed-off-by: Luciano Coelho <luciano.coelho@nokia.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
---
 include/linux/netfilter/Kbuild         |    1 +
 include/linux/netfilter/xt_IDLETIMER.h |   45 +++++
 net/netfilter/Kconfig                  |   12 ++
 net/netfilter/Makefile                 |    1 +
 net/netfilter/xt_IDLETIMER.c           |  314 ++++++++++++++++++++++++++++++++
 5 files changed, 373 insertions(+), 0 deletions(-)
 create mode 100644 include/linux/netfilter/xt_IDLETIMER.h
 create mode 100644 net/netfilter/xt_IDLETIMER.c

diff --git a/include/linux/netfilter/Kbuild b/include/linux/netfilter/Kbuild
index 48767cd..bb103f4 100644
--- a/include/linux/netfilter/Kbuild
+++ b/include/linux/netfilter/Kbuild
@@ -8,6 +8,7 @@ header-y += xt_CONNMARK.h
 header-y += xt_CONNSECMARK.h
 header-y += xt_CT.h
 header-y += xt_DSCP.h
+header-y += xt_IDLETIMER.h
 header-y += xt_LED.h
 header-y += xt_MARK.h
 header-y += xt_NFLOG.h
diff --git a/include/linux/netfilter/xt_IDLETIMER.h b/include/linux/netfilter/xt_IDLETIMER.h
new file mode 100644
index 0000000..3e1aa1b
--- /dev/null
+++ b/include/linux/netfilter/xt_IDLETIMER.h
@@ -0,0 +1,45 @@
+/*
+ * linux/include/linux/netfilter/xt_IDLETIMER.h
+ *
+ * Header file for Xtables timer target module.
+ *
+ * Copyright (C) 2004, 2010 Nokia Corporation
+ * Written by Timo Teras <ext-timo.teras@nokia.com>
+ *
+ * Converted to x_tables and forward-ported to 2.6.34
+ * by Luciano Coelho <luciano.coelho@nokia.com>
+ *
+ * Contact: Luciano Coelho <luciano.coelho@nokia.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#ifndef _XT_IDLETIMER_H
+#define _XT_IDLETIMER_H
+
+#include <linux/types.h>
+
+#define MAX_IDLETIMER_LABEL_SIZE 28
+
+struct idletimer_tg_info {
+	__u32 timeout;
+
+	char label[MAX_IDLETIMER_LABEL_SIZE];
+
+	/* for kernel module internal use only */
+	struct idletimer_tg *timer __attribute((aligned(8)));
+};
+
+#endif
diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig
index 8593a77..413ed24 100644
--- a/net/netfilter/Kconfig
+++ b/net/netfilter/Kconfig
@@ -424,6 +424,18 @@ config NETFILTER_XT_TARGET_HL
 	since you can easily create immortal packets that loop
 	forever on the network.
 
+config NETFILTER_XT_TARGET_IDLETIMER
+	tristate  "IDLETIMER target support"
+	depends on NETFILTER_ADVANCED
+	help
+
+	  This option adds the `IDLETIMER' target.  Each matching packet
+	  resets the timer associated with label specified when the rule is
+	  added.  When the timer expires, it triggers a sysfs notification.
+	  The remaining time for expiration can be read via sysfs.
+
+	  To compile it as a module, choose M here.  If unsure, say N.
+
 config NETFILTER_XT_TARGET_LED
 	tristate '"LED" target support'
 	depends on LEDS_CLASS && LEDS_TRIGGERS
diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile
index 14e3a8f..e28420a 100644
--- a/net/netfilter/Makefile
+++ b/net/netfilter/Makefile
@@ -61,6 +61,7 @@ obj-$(CONFIG_NETFILTER_XT_TARGET_TCPMSS) += xt_TCPMSS.o
 obj-$(CONFIG_NETFILTER_XT_TARGET_TCPOPTSTRIP) += xt_TCPOPTSTRIP.o
 obj-$(CONFIG_NETFILTER_XT_TARGET_TEE) += xt_TEE.o
 obj-$(CONFIG_NETFILTER_XT_TARGET_TRACE) += xt_TRACE.o
+obj-$(CONFIG_NETFILTER_XT_TARGET_IDLETIMER) += xt_IDLETIMER.o
 
 # matches
 obj-$(CONFIG_NETFILTER_XT_MATCH_CLUSTER) += xt_cluster.o
diff --git a/net/netfilter/xt_IDLETIMER.c b/net/netfilter/xt_IDLETIMER.c
new file mode 100644
index 0000000..e11090a
--- /dev/null
+++ b/net/netfilter/xt_IDLETIMER.c
@@ -0,0 +1,314 @@
+/*
+ * linux/net/netfilter/xt_IDLETIMER.c
+ *
+ * Netfilter module to trigger a timer when packet matches.
+ * After timer expires a kevent will be sent.
+ *
+ * Copyright (C) 2004, 2010 Nokia Corporation
+ * Written by Timo Teras <ext-timo.teras@nokia.com>
+ *
+ * Converted to x_tables and reworked for upstream inclusion
+ * by Luciano Coelho <luciano.coelho@nokia.com>
+ *
+ * Contact: Luciano Coelho <luciano.coelho@nokia.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/timer.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/netfilter.h>
+#include <linux/netfilter/x_tables.h>
+#include <linux/netfilter/xt_IDLETIMER.h>
+#include <linux/kobject.h>
+#include <linux/workqueue.h>
+#include <linux/sysfs.h>
+
+struct idletimer_tg_attr {
+	struct attribute attr;
+	ssize_t	(*show)(struct kobject *kobj,
+			struct attribute *attr, char *buf);
+};
+
+struct idletimer_tg {
+	struct list_head entry;
+	struct timer_list timer;
+	struct work_struct work;
+
+	struct kobject *kobj;
+	struct idletimer_tg_attr attr;
+
+	unsigned int refcnt;
+};
+
+static LIST_HEAD(idletimer_tg_list);
+static DEFINE_MUTEX(list_mutex);
+
+static struct kobject *idletimer_tg_kobj;
+
+static
+struct idletimer_tg *__idletimer_tg_find_by_label(const char *label)
+{
+	struct idletimer_tg *entry;
+
+	BUG_ON(!label);
+
+	list_for_each_entry(entry, &idletimer_tg_list, entry) {
+		if (!strcmp(label, entry->attr.attr.name))
+			return entry;
+	}
+
+	return NULL;
+}
+
+static ssize_t idletimer_tg_show(struct kobject *kobj, struct attribute *attr,
+				 char *buf)
+{
+	struct idletimer_tg *timer;
+	unsigned long expires = 0;
+
+	mutex_lock(&list_mutex);
+
+	timer =	__idletimer_tg_find_by_label(attr->name);
+	if (timer)
+		expires = timer->timer.expires;
+
+	mutex_unlock(&list_mutex);
+
+	if (time_after(expires, jiffies))
+		return sprintf(buf, "%u\n",
+			       jiffies_to_msecs(expires - jiffies) / 1000);
+
+	return sprintf(buf, "0\n");
+}
+
+static void idletimer_tg_work(struct work_struct *work)
+{
+	struct idletimer_tg *timer = container_of(work, struct idletimer_tg,
+						  work);
+
+	sysfs_notify(idletimer_tg_kobj, NULL, timer->attr.attr.name);
+}
+
+static void idletimer_tg_expired(unsigned long data)
+{
+	struct idletimer_tg *timer = (struct idletimer_tg *) data;
+
+	pr_debug("timer %s expired\n", timer->attr.attr.name);
+
+	schedule_work(&timer->work);
+}
+
+static int idletimer_tg_create(struct idletimer_tg_info *info)
+{
+	int ret;
+
+	info->timer = kmalloc(sizeof(*info->timer), GFP_KERNEL);
+	if (!info->timer) {
+		pr_debug("couldn't alloc timer\n");
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	info->timer->attr.attr.name = kstrdup(info->label, GFP_KERNEL);
+	if (!info->timer->attr.attr.name) {
+		pr_debug("couldn't alloc attribute name\n");
+		ret = -ENOMEM;
+		goto out_free_timer;
+	}
+	info->timer->attr.attr.mode = S_IRUGO;
+	info->timer->attr.show = idletimer_tg_show;
+
+	ret = sysfs_create_file(idletimer_tg_kobj, &info->timer->attr.attr);
+	if (ret < 0) {
+		pr_debug("couldn't add file to sysfs");
+		goto out_free_attr;
+	}
+
+	list_add(&info->timer->entry, &idletimer_tg_list);
+
+	setup_timer(&info->timer->timer, idletimer_tg_expired,
+		    (unsigned long) info->timer);
+	info->timer->refcnt = 1;
+
+	mod_timer(&info->timer->timer,
+		  msecs_to_jiffies(info->timeout * 1000) + jiffies);
+
+	INIT_WORK(&info->timer->work, idletimer_tg_work);
+
+	return 0;
+
+out_free_attr:
+	kfree(info->timer->attr.attr.name);
+out_free_timer:
+	kfree(info->timer);
+out:
+	return ret;
+}
+
+/*
+ * The actual xt_tables plugin.
+ */
+static unsigned int idletimer_tg_target(struct sk_buff *skb,
+					 const struct xt_action_param *par)
+{
+	const struct idletimer_tg_info *info = par->targinfo;
+
+	pr_debug("resetting timer %s, timeout period %u\n",
+		 info->label, info->timeout);
+
+	BUG_ON(!info->timer);
+
+	mod_timer(&info->timer->timer,
+		  msecs_to_jiffies(info->timeout * 1000) + jiffies);
+
+	return XT_CONTINUE;
+}
+
+static int idletimer_tg_checkentry(const struct xt_tgchk_param *par)
+{
+	struct idletimer_tg_info *info = par->targinfo;
+	int ret;
+
+	pr_debug("checkentry targinfo%s\n", info->label);
+
+	if (info->timeout == 0) {
+		pr_debug("timeout value is zero\n");
+		return -EINVAL;
+	}
+
+	if (info->label[0] == '\0' ||
+	    strnlen(info->label,
+		    MAX_IDLETIMER_LABEL_SIZE) == MAX_IDLETIMER_LABEL_SIZE) {
+		pr_debug("label is empty or not nul-terminated\n");
+		return -EINVAL;
+	}
+
+	mutex_lock(&list_mutex);
+
+	info->timer = __idletimer_tg_find_by_label(info->label);
+	if (info->timer) {
+		info->timer->refcnt++;
+		mod_timer(&info->timer->timer,
+			  msecs_to_jiffies(info->timeout * 1000) + jiffies);
+
+		pr_debug("increased refcnt of timer %s to %u\n",
+			 info->label, info->timer->refcnt);
+	} else {
+		ret = idletimer_tg_create(info);
+		if (ret < 0) {
+			pr_debug("failed to create timer\n");
+			mutex_unlock(&list_mutex);
+			return ret;
+		}
+	}
+
+	mutex_unlock(&list_mutex);
+	return 0;
+}
+
+static void idletimer_tg_destroy(const struct xt_tgdtor_param *par)
+{
+	const struct idletimer_tg_info *info = par->targinfo;
+
+	pr_debug("destroy targinfo %s\n", info->label);
+
+	mutex_lock(&list_mutex);
+
+	if (--info->timer->refcnt == 0) {
+		pr_debug("deleting timer %s\n", info->label);
+
+		list_del(&info->timer->entry);
+		del_timer_sync(&info->timer->timer);
+		sysfs_remove_file(idletimer_tg_kobj, &info->timer->attr.attr);
+		kfree(info->timer->attr.attr.name);
+		kfree(info->timer);
+	} else {
+		pr_debug("decreased refcnt of timer %s to %u\n",
+			 info->label, info->timer->refcnt);
+	}
+
+	mutex_unlock(&list_mutex);
+}
+
+static struct xt_target idletimer_tg __read_mostly = {
+	.name		= "IDLETIMER",
+	.family		= NFPROTO_UNSPEC,
+	.target		= idletimer_tg_target,
+	.targetsize     = sizeof(struct idletimer_tg_info),
+	.checkentry	= idletimer_tg_checkentry,
+	.destroy        = idletimer_tg_destroy,
+	.me		= THIS_MODULE,
+};
+
+static struct class *idletimer_tg_class;
+
+static struct device *idletimer_tg_device;
+
+static int __init idletimer_tg_init(void)
+{
+	int err;
+
+	idletimer_tg_class = class_create(THIS_MODULE, "xt_idletimer");
+	err = PTR_ERR(idletimer_tg_class);
+	if (IS_ERR(idletimer_tg_class)) {
+		pr_debug("couldn't register device class\n");
+		goto out;
+	}
+
+	idletimer_tg_device = device_create(idletimer_tg_class, NULL,
+					    MKDEV(0, 0), NULL, "timers");
+	err = PTR_ERR(idletimer_tg_device);
+	if (IS_ERR(idletimer_tg_device)) {
+		pr_debug("couldn't register system device\n");
+		goto out_class;
+	}
+
+	idletimer_tg_kobj = &idletimer_tg_device->kobj;
+
+	err =  xt_register_target(&idletimer_tg);
+	if (err < 0) {
+		pr_debug("couldn't register xt target\n");
+		goto out_dev;
+	}
+
+	return 0;
+out_dev:
+	device_destroy(idletimer_tg_class, MKDEV(0, 0));
+out_class:
+	class_destroy(idletimer_tg_class);
+out:
+	return err;
+}
+
+static void __exit idletimer_tg_exit(void)
+{
+	xt_unregister_target(&idletimer_tg);
+
+	device_destroy(idletimer_tg_class, MKDEV(0, 0));
+	class_destroy(idletimer_tg_class);
+}
+
+module_init(idletimer_tg_init);
+module_exit(idletimer_tg_exit);
+
+MODULE_AUTHOR("Timo Teras <ext-timo.teras@nokia.com>");
+MODULE_AUTHOR("Luciano Coelho <luciano.coelho@nokia.com>");
+MODULE_DESCRIPTION("Xtables: idle time monitor");
+MODULE_LICENSE("GPL v2");
-- 
1.7.0.4

Re: [PATCH 00/17] netfilter: netfilter update

[David Miller]

From: kaber@trash.net
Date: Tue, 15 Jun 2010 17:38:26 +0200

> Please pull from:
> 
> git://git.kernel.org/pub/scm/linux/kernel/git/kaber/nf-next-2.6.git master

Pulled, thanks Patrick.