[PATCH net-next 8/9] netns: place rt_genid into struct net

["Denis V. Lunev" <den@openvz.org>]

Signed-off-by: Denis V. Lunev <den@openvz.org>
---
 include/net/netns/ipv4.h |    1 +
 net/ipv4/route.c         |   76 ++++++++++++++++++++++++++--------------------
 2 files changed, 44 insertions(+), 33 deletions(-)

diff --git a/include/net/netns/ipv4.h b/include/net/netns/ipv4.h
index 356617f..a6ed838 100644
--- a/include/net/netns/ipv4.h
+++ b/include/net/netns/ipv4.h
@@ -48,5 +48,6 @@ struct netns_ipv4 {
 	int sysctl_icmp_errors_use_inbound_ifaddr;
 
 	struct timer_list rt_secret_timer;
+	atomic_t rt_genid;
 };
 #endif
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index e4e37ed..67c3ed7 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -250,7 +250,6 @@ static inline void rt_hash_lock_init(void)
 static struct rt_hash_bucket 	*rt_hash_table __read_mostly;
 static unsigned			rt_hash_mask __read_mostly;
 static unsigned int		rt_hash_log  __read_mostly;
-static atomic_t			rt_genid __read_mostly;
 
 static DEFINE_PER_CPU(struct rt_cache_stat, rt_cache_stat);
 #define RT_CACHE_STAT_INC(field) \
@@ -265,6 +264,11 @@ static inline unsigned int rt_hash(__be32 daddr, __be32 saddr, int idx,
 		& rt_hash_mask;
 }
 
+static inline int rt_genid(struct net *net)
+{
+	return atomic_read(&net->ipv4.rt_genid);
+}
+
 #ifdef CONFIG_PROC_FS
 struct rt_cache_iter_state {
 	struct seq_net_private p;
@@ -334,7 +338,7 @@ static void *rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
 	struct rt_cache_iter_state *st = seq->private;
 	if (*pos)
 		return rt_cache_get_idx(seq, *pos - 1);
-	st->genid = atomic_read(&rt_genid);
+	st->genid = rt_genid(seq_file_net(seq));
 	return SEQ_START_TOKEN;
 }
 
@@ -681,6 +685,11 @@ static inline int compare_netns(struct rtable *rt1, struct rtable *rt2)
 	return dev_net(rt1->u.dst.dev) == dev_net(rt2->u.dst.dev);
 }
 
+static inline int rt_is_expired(struct rtable *rth)
+{
+	return rth->rt_genid != rt_genid(dev_net(rth->u.dst.dev));
+}
+
 /*
  * Perform a full scan of hash table and free all entries.
  * Can be called by a softirq or a process.
@@ -736,7 +745,7 @@ static void rt_check_expire(void)
 			continue;
 		spin_lock_bh(rt_hash_lock_addr(i));
 		while ((rth = *rthp) != NULL) {
-			if (rth->rt_genid != atomic_read(&rt_genid)) {
+			if (rt_is_expired(rth)) {
 				*rthp = rth->u.dst.rt_next;
 				rt_free(rth);
 				continue;
@@ -784,7 +793,7 @@ static void rt_cache_invalidate(struct net *net)
 	unsigned char shuffle;
 
 	get_random_bytes(&shuffle, sizeof(shuffle));
-	atomic_add(shuffle + 1U, &rt_genid);
+	atomic_add(shuffle + 1U, &net->ipv4.rt_genid);
 }
 
 /*
@@ -881,7 +890,7 @@ static int rt_garbage_collect(struct dst_ops *ops)
 			rthp = &rt_hash_table[k].chain;
 			spin_lock_bh(rt_hash_lock_addr(k));
 			while ((rth = *rthp) != NULL) {
-				if (rth->rt_genid == atomic_read(&rt_genid) &&
+				if (!rt_is_expired(rth) &&
 					!rt_may_expire(rth, tmo, expire)) {
 					tmo >>= 1;
 					rthp = &rth->u.dst.rt_next;
@@ -963,7 +972,7 @@ restart:
 
 	spin_lock_bh(rt_hash_lock_addr(hash));
 	while ((rth = *rthp) != NULL) {
-		if (rth->rt_genid != atomic_read(&rt_genid)) {
+		if (rt_is_expired(rth)) {
 			*rthp = rth->u.dst.rt_next;
 			rt_free(rth);
 			continue;
@@ -1139,7 +1148,7 @@ static void rt_del(unsigned hash, struct rtable *rt)
 	spin_lock_bh(rt_hash_lock_addr(hash));
 	ip_rt_put(rt);
 	while ((aux = *rthp) != NULL) {
-		if (aux == rt || (aux->rt_genid != atomic_read(&rt_genid))) {
+		if (aux == rt || rt_is_expired(aux)) {
 			*rthp = aux->u.dst.rt_next;
 			rt_free(aux);
 			continue;
@@ -1182,7 +1191,7 @@ void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw,
 	for (i = 0; i < 2; i++) {
 		for (k = 0; k < 2; k++) {
 			unsigned hash = rt_hash(daddr, skeys[i], ikeys[k],
-						atomic_read(&rt_genid));
+						rt_genid(net));
 
 			rthp=&rt_hash_table[hash].chain;
 
@@ -1194,7 +1203,7 @@ void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw,
 				    rth->fl.fl4_src != skeys[i] ||
 				    rth->fl.oif != ikeys[k] ||
 				    rth->fl.iif != 0 ||
-				    rth->rt_genid != atomic_read(&rt_genid) ||
+				    rt_is_expired(rth) ||
 				    !net_eq(dev_net(rth->u.dst.dev), net)) {
 					rthp = &rth->u.dst.rt_next;
 					continue;
@@ -1233,7 +1242,7 @@ void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw,
 				rt->u.dst.neighbour	= NULL;
 				rt->u.dst.hh		= NULL;
 				rt->u.dst.xfrm		= NULL;
-				rt->rt_genid		= atomic_read(&rt_genid);
+				rt->rt_genid		= rt_genid(net);
 				rt->rt_flags		|= RTCF_REDIRECTED;
 
 				/* Gateway is different ... */
@@ -1298,7 +1307,7 @@ static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst)
 			   rt->u.dst.expires) {
 			unsigned hash = rt_hash(rt->fl.fl4_dst, rt->fl.fl4_src,
 						rt->fl.oif,
-						atomic_read(&rt_genid));
+						rt_genid(dev_net(dst->dev)));
 #if RT_CACHE_DEBUG >= 1
 			printk(KERN_DEBUG "ipv4_negative_advice: redirect to "
 					  NIPQUAD_FMT "/%02x dropped\n",
@@ -1448,7 +1457,7 @@ unsigned short ip_rt_frag_needed(struct net *net, struct iphdr *iph,
 	for (k = 0; k < 2; k++) {
 		for (i = 0; i < 2; i++) {
 			unsigned hash = rt_hash(daddr, skeys[i], ikeys[k],
-						atomic_read(&rt_genid));
+						rt_genid(net));
 
 			rcu_read_lock();
 			for (rth = rcu_dereference(rt_hash_table[hash].chain); rth;
@@ -1463,7 +1472,7 @@ unsigned short ip_rt_frag_needed(struct net *net, struct iphdr *iph,
 				    rth->fl.iif != 0 ||
 				    dst_metric_locked(&rth->u.dst, RTAX_MTU) ||
 				    !net_eq(dev_net(rth->u.dst.dev), net) ||
-				    rth->rt_genid != atomic_read(&rt_genid))
+				    !rt_is_expired(rth))
 					continue;
 
 				if (new_mtu < 68 || new_mtu >= old_mtu) {
@@ -1698,7 +1707,7 @@ static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr,
 	rth->fl.oif	= 0;
 	rth->rt_gateway	= daddr;
 	rth->rt_spec_dst= spec_dst;
-	rth->rt_genid	= atomic_read(&rt_genid);
+	rth->rt_genid	= rt_genid(dev_net(dev));
 	rth->rt_flags	= RTCF_MULTICAST;
 	rth->rt_type	= RTN_MULTICAST;
 	if (our) {
@@ -1713,7 +1722,7 @@ static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr,
 	RT_CACHE_STAT_INC(in_slow_mc);
 
 	in_dev_put(in_dev);
-	hash = rt_hash(daddr, saddr, dev->ifindex, atomic_read(&rt_genid));
+	hash = rt_hash(daddr, saddr, dev->ifindex, rt_genid(dev_net(dev)));
 	return rt_intern_hash(hash, rth, &skb->rtable);
 
 e_nobufs:
@@ -1839,7 +1848,7 @@ static int __mkroute_input(struct sk_buff *skb,
 
 	rth->u.dst.input = ip_forward;
 	rth->u.dst.output = ip_output;
-	rth->rt_genid = atomic_read(&rt_genid);
+	rth->rt_genid = rt_genid(dev_net(rth->u.dst.dev));
 
 	rt_set_nexthop(rth, res, itag);
 
@@ -1874,7 +1883,8 @@ static int ip_mkroute_input(struct sk_buff *skb,
 		return err;
 
 	/* put it into the cache */
-	hash = rt_hash(daddr, saddr, fl->iif, atomic_read(&rt_genid));
+	hash = rt_hash(daddr, saddr, fl->iif,
+		       rt_genid(dev_net(rth->u.dst.dev)));
 	return rt_intern_hash(hash, rth, &skb->rtable);
 }
 
@@ -2000,7 +2010,7 @@ local_input:
 		goto e_nobufs;
 
 	rth->u.dst.output= ip_rt_bug;
-	rth->rt_genid = atomic_read(&rt_genid);
+	rth->rt_genid = rt_genid(net);
 
 	atomic_set(&rth->u.dst.__refcnt, 1);
 	rth->u.dst.flags= DST_HOST;
@@ -2030,7 +2040,7 @@ local_input:
 		rth->rt_flags 	&= ~RTCF_LOCAL;
 	}
 	rth->rt_type	= res.type;
-	hash = rt_hash(daddr, saddr, fl.iif, atomic_read(&rt_genid));
+	hash = rt_hash(daddr, saddr, fl.iif, rt_genid(net));
 	err = rt_intern_hash(hash, rth, &skb->rtable);
 	goto done;
 
@@ -2081,7 +2091,7 @@ int ip_route_input(struct sk_buff *skb, __be32 daddr, __be32 saddr,
 
 	net = dev_net(dev);
 	tos &= IPTOS_RT_MASK;
-	hash = rt_hash(daddr, saddr, iif, atomic_read(&rt_genid));
+	hash = rt_hash(daddr, saddr, iif, rt_genid(net));
 
 	rcu_read_lock();
 	for (rth = rcu_dereference(rt_hash_table[hash].chain); rth;
@@ -2093,7 +2103,7 @@ int ip_route_input(struct sk_buff *skb, __be32 daddr, __be32 saddr,
 		     (rth->fl.fl4_tos ^ tos)) == 0 &&
 		    rth->fl.mark == skb->mark &&
 		    net_eq(dev_net(rth->u.dst.dev), net) &&
-		    rth->rt_genid == atomic_read(&rt_genid)) {
+		    !rt_is_expired(rth)) {
 			dst_use(&rth->u.dst, jiffies);
 			RT_CACHE_STAT_INC(in_hit);
 			rcu_read_unlock();
@@ -2221,7 +2231,7 @@ static int __mkroute_output(struct rtable **result,
 	rth->rt_spec_dst= fl->fl4_src;
 
 	rth->u.dst.output=ip_output;
-	rth->rt_genid = atomic_read(&rt_genid);
+	rth->rt_genid = rt_genid(dev_net(dev_out));
 
 	RT_CACHE_STAT_INC(out_slow_tot);
 
@@ -2271,7 +2281,7 @@ static int ip_mkroute_output(struct rtable **rp,
 	unsigned hash;
 	if (err == 0) {
 		hash = rt_hash(oldflp->fl4_dst, oldflp->fl4_src, oldflp->oif,
-			       atomic_read(&rt_genid));
+			       rt_genid(dev_net(dev_out)));
 		err = rt_intern_hash(hash, rth, rp);
 	}
 
@@ -2483,8 +2493,7 @@ int __ip_route_output_key(struct net *net, struct rtable **rp,
 	unsigned hash;
 	struct rtable *rth;
 
-	hash = rt_hash(flp->fl4_dst, flp->fl4_src, flp->oif,
-		       atomic_read(&rt_genid));
+	hash = rt_hash(flp->fl4_dst, flp->fl4_src, flp->oif, rt_genid(net));
 
 	rcu_read_lock_bh();
 	for (rth = rcu_dereference(rt_hash_table[hash].chain); rth;
@@ -2497,7 +2506,7 @@ int __ip_route_output_key(struct net *net, struct rtable **rp,
 		    !((rth->fl.fl4_tos ^ flp->fl4_tos) &
 			    (IPTOS_RT_MASK | RTO_ONLINK)) &&
 		    net_eq(dev_net(rth->u.dst.dev), net) &&
-		    rth->rt_genid == atomic_read(&rt_genid)) {
+		    !rt_is_expired(rth)) {
 			dst_use(&rth->u.dst, jiffies);
 			RT_CACHE_STAT_INC(out_hit);
 			rcu_read_unlock_bh();
@@ -2528,7 +2537,7 @@ static struct dst_ops ipv4_dst_blackhole_ops = {
 };
 
 
-static int ipv4_dst_blackhole(struct rtable **rp, struct flowi *flp)
+static int ipv4_dst_blackhole(struct net *net, struct rtable **rp, struct flowi *flp)
 {
 	struct rtable *ort = *rp;
 	struct rtable *rt = (struct rtable *)
@@ -2552,7 +2561,7 @@ static int ipv4_dst_blackhole(struct rtable **rp, struct flowi *flp)
 		rt->idev = ort->idev;
 		if (rt->idev)
 			in_dev_hold(rt->idev);
-		rt->rt_genid = atomic_read(&rt_genid);
+		rt->rt_genid = rt_genid(net);
 		rt->rt_flags = ort->rt_flags;
 		rt->rt_type = ort->rt_type;
 		rt->rt_dst = ort->rt_dst;
@@ -2588,7 +2597,7 @@ int ip_route_output_flow(struct net *net, struct rtable **rp, struct flowi *flp,
 		err = __xfrm_lookup((struct dst_entry **)rp, flp, sk,
 				    flags ? XFRM_LOOKUP_WAIT : 0);
 		if (err == -EREMOTE)
-			err = ipv4_dst_blackhole(rp, flp);
+			err = ipv4_dst_blackhole(net, rp, flp);
 
 		return err;
 	}
@@ -2807,7 +2816,7 @@ int ip_rt_dump(struct sk_buff *skb,  struct netlink_callback *cb)
 		     rt = rcu_dereference(rt->u.dst.rt_next), idx++) {
 			if (!net_eq(dev_net(rt->u.dst.dev), net) || idx < s_idx)
 				continue;
-			if (rt->rt_genid != atomic_read(&rt_genid))
+			if (rt_is_expired(rt))
 				continue;
 			skb->dst = dst_clone(&rt->u.dst);
 			if (rt_fill_info(skb, NETLINK_CB(cb->skb).pid,
@@ -3081,6 +3090,10 @@ static __net_initdata struct pernet_operations sysctl_route_ops = {
 
 static __net_init int rt_secret_timer_init(struct net *net)
 {
+	atomic_set(&net->ipv4.rt_genid,
+			(int) ((num_physpages ^ (num_physpages>>8)) ^
+			(jiffies ^ (jiffies >> 7))));
+
 	net->ipv4.rt_secret_timer.function = rt_secret_rebuild;
 	net->ipv4.rt_secret_timer.data = (unsigned long)net;
 	init_timer_deferrable(&net->ipv4.rt_secret_timer);
@@ -3121,9 +3134,6 @@ int __init ip_rt_init(void)
 {
 	int rc = 0;
 
-	atomic_set(&rt_genid, (int) ((num_physpages ^ (num_physpages>>8)) ^
-			     (jiffies ^ (jiffies >> 7))));
-
 #ifdef CONFIG_NET_CLS_ROUTE
 	ip_rt_acct = __alloc_percpu(256 * sizeof(struct ip_rt_acct));
 	if (!ip_rt_acct)
-- 
1.5.3.rc5