From 5943634fc5592037db0693b261f7f4bea6bb9457 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Tue, 10 Jul 2012 06:58:42 -0700 Subject: [PATCH] ipv4: Maintain redirect and PMTU info in struct rtable again. Maintaining this in the inetpeer entries was not the right way to do this at all. Signed-off-by: David S. Miller --- include/net/inetpeer.h | 4 - include/net/route.h | 2 +- net/ipv4/inetpeer.c | 3 - net/ipv4/route.c | 185 +++++++++------------------------------- net/ipv4/xfrm4_policy.c | 1 + 5 files changed, 41 insertions(+), 154 deletions(-) diff --git a/include/net/inetpeer.h b/include/net/inetpeer.h index 1119f6f6cdb4..53f464d7cddc 100644 --- a/include/net/inetpeer.h +++ b/include/net/inetpeer.h @@ -36,10 +36,6 @@ struct inet_peer { u32 metrics[RTAX_MAX]; u32 rate_tokens; /* rate limiting for ICMP */ unsigned long rate_last; - unsigned long pmtu_expires; - u32 pmtu_orig; - u32 pmtu_learned; - struct inetpeer_addr_base redirect_learned; union { struct list_head gc_list; struct rcu_head gc_rcu; diff --git a/include/net/route.h b/include/net/route.h index 635d7a99d199..c27449466d18 100644 --- a/include/net/route.h +++ b/include/net/route.h @@ -65,7 +65,7 @@ struct rtable { __be32 rt_gateway; /* Miscellaneous cached information */ - u32 rt_peer_genid; + u32 rt_pmtu; unsigned long _peer; /* long-living peer info */ struct fib_info *fi; /* for client ref to shared metrics */ }; diff --git a/net/ipv4/inetpeer.c b/net/ipv4/inetpeer.c index f457bcb41350..e1e0a4e8fd34 100644 --- a/net/ipv4/inetpeer.c +++ b/net/ipv4/inetpeer.c @@ -511,9 +511,6 @@ relookup: p->metrics[RTAX_LOCK-1] = INETPEER_METRICS_NEW; p->rate_tokens = 0; p->rate_last = 0; - p->pmtu_expires = 0; - p->pmtu_orig = 0; - memset(&p->redirect_learned, 0, sizeof(p->redirect_learned)); INIT_LIST_HEAD(&p->gc_list); /* Link the node. */ diff --git a/net/ipv4/route.c b/net/ipv4/route.c index 67b08745daf9..677d65253e4c 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -669,7 +669,7 @@ static inline int rt_fast_clean(struct rtable *rth) static inline int rt_valuable(struct rtable *rth) { return (rth->rt_flags & (RTCF_REDIRECTED | RTCF_NOTIFY)) || - (rt_has_peer(rth) && rt_peer_ptr(rth)->pmtu_expires); + rth->dst.expires; } static int rt_may_expire(struct rtable *rth, unsigned long tmo1, unsigned long tmo2) @@ -1242,13 +1242,6 @@ skip_hashing: return rt; } -static atomic_t __rt_peer_genid = ATOMIC_INIT(0); - -static u32 rt_peer_genid(void) -{ - return atomic_read(&__rt_peer_genid); -} - void rt_bind_peer(struct rtable *rt, __be32 daddr, int create) { struct inet_peer_base *base; @@ -1262,8 +1255,6 @@ void rt_bind_peer(struct rtable *rt, __be32 daddr, int create) if (peer) { if (!rt_set_peer(rt, peer)) inet_putpeer(peer); - else - rt->rt_peer_genid = rt_peer_genid(); } } @@ -1323,30 +1314,6 @@ static void rt_del(unsigned int hash, struct rtable *rt) spin_unlock_bh(rt_hash_lock_addr(hash)); } -static void check_peer_redir(struct dst_entry *dst, struct inet_peer *peer) -{ - struct rtable *rt = (struct rtable *) dst; - __be32 orig_gw = rt->rt_gateway; - struct neighbour *n; - - dst_confirm(&rt->dst); - - rt->rt_gateway = peer->redirect_learned.a4; - - n = ipv4_neigh_lookup(&rt->dst, NULL, &rt->rt_gateway); - if (!n) { - rt->rt_gateway = orig_gw; - return; - } - if (!(n->nud_state & NUD_VALID)) { - neigh_event_send(n, NULL); - } else { - rt->rt_flags |= RTCF_REDIRECTED; - call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, n); - } - neigh_release(n); -} - /* called in rcu_read_lock() section */ void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw, __be32 saddr, struct net_device *dev) @@ -1355,7 +1322,6 @@ void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw, struct in_device *in_dev = __in_dev_get_rcu(dev); __be32 skeys[2] = { saddr, 0 }; int ikeys[2] = { dev->ifindex, 0 }; - struct inet_peer *peer; struct net *net; if (!in_dev) @@ -1388,6 +1354,8 @@ void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw, rthp = &rt_hash_table[hash].chain; while ((rt = rcu_dereference(*rthp)) != NULL) { + struct neighbour *n; + rthp = &rt->dst.rt_next; if (rt->rt_key_dst != daddr || @@ -1401,13 +1369,16 @@ void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw, rt->rt_gateway != old_gw) continue; - peer = rt_get_peer_create(rt, rt->rt_dst); - if (peer) { - if (peer->redirect_learned.a4 != new_gw) { - peer->redirect_learned.a4 = new_gw; - atomic_inc(&__rt_peer_genid); + n = ipv4_neigh_lookup(&rt->dst, NULL, &new_gw); + if (n) { + if (!(n->nud_state & NUD_VALID)) { + neigh_event_send(n, NULL); + } else { + rt->rt_gateway = new_gw; + rt->rt_flags |= RTCF_REDIRECTED; + call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, n); } - check_peer_redir(&rt->dst, peer); + neigh_release(n); } } } @@ -1425,23 +1396,6 @@ reject_redirect: ; } -static bool peer_pmtu_expired(struct inet_peer *peer) -{ - unsigned long orig = ACCESS_ONCE(peer->pmtu_expires); - - return orig && - time_after_eq(jiffies, orig) && - cmpxchg(&peer->pmtu_expires, orig, 0) == orig; -} - -static bool peer_pmtu_cleaned(struct inet_peer *peer) -{ - unsigned long orig = ACCESS_ONCE(peer->pmtu_expires); - - return orig && - cmpxchg(&peer->pmtu_expires, orig, 0) == orig; -} - static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst) { struct rtable *rt = (struct rtable *)dst; @@ -1451,16 +1405,13 @@ static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst) if (dst->obsolete > 0) { ip_rt_put(rt); ret = NULL; - } else if (rt->rt_flags & RTCF_REDIRECTED) { + } else if ((rt->rt_flags & RTCF_REDIRECTED) || + rt->dst.expires) { unsigned int hash = rt_hash(rt->rt_key_dst, rt->rt_key_src, rt->rt_oif, rt_genid(dev_net(dst->dev))); rt_del(hash, rt); ret = NULL; - } else if (rt_has_peer(rt)) { - struct inet_peer *peer = rt_peer_ptr(rt); - if (peer_pmtu_expired(peer)) - dst_metric_set(dst, RTAX_MTU, peer->pmtu_orig); } } return ret; @@ -1604,50 +1555,17 @@ out: kfree_skb(skb); return 0; } -static void check_peer_pmtu(struct dst_entry *dst, struct inet_peer *peer) -{ - unsigned long expires = ACCESS_ONCE(peer->pmtu_expires); - - if (!expires) - return; - if (time_before(jiffies, expires)) { - u32 orig_dst_mtu = dst_mtu(dst); - if (peer->pmtu_learned < orig_dst_mtu) { - if (!peer->pmtu_orig) - peer->pmtu_orig = dst_metric_raw(dst, RTAX_MTU); - dst_metric_set(dst, RTAX_MTU, peer->pmtu_learned); - } - } else if (cmpxchg(&peer->pmtu_expires, expires, 0) == expires) - dst_metric_set(dst, RTAX_MTU, peer->pmtu_orig); -} - static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu) { struct rtable *rt = (struct rtable *) dst; - struct inet_peer *peer; dst_confirm(dst); - peer = rt_get_peer_create(rt, rt->rt_dst); - if (peer) { - unsigned long pmtu_expires = ACCESS_ONCE(peer->pmtu_expires); - - if (mtu < ip_rt_min_pmtu) - mtu = ip_rt_min_pmtu; - if (!pmtu_expires || mtu < peer->pmtu_learned) { - - pmtu_expires = jiffies + ip_rt_mtu_expires; - if (!pmtu_expires) - pmtu_expires = 1UL; - - peer->pmtu_learned = mtu; - peer->pmtu_expires = pmtu_expires; + if (mtu < ip_rt_min_pmtu) + mtu = ip_rt_min_pmtu; - atomic_inc(&__rt_peer_genid); - rt->rt_peer_genid = rt_peer_genid(); - } - check_peer_pmtu(dst, peer); - } + rt->rt_pmtu = mtu; + dst_set_expires(&rt->dst, ip_rt_mtu_expires); } void ipv4_update_pmtu(struct sk_buff *skb, struct net *net, u32 mtu, @@ -1679,30 +1597,12 @@ void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu) } EXPORT_SYMBOL_GPL(ipv4_sk_update_pmtu); -static void ipv4_validate_peer(struct rtable *rt) -{ - if (rt->rt_peer_genid != rt_peer_genid()) { - struct inet_peer *peer = rt_get_peer(rt, rt->rt_dst); - - if (peer) { - check_peer_pmtu(&rt->dst, peer); - - if (peer->redirect_learned.a4 && - peer->redirect_learned.a4 != rt->rt_gateway) - check_peer_redir(&rt->dst, peer); - } - - rt->rt_peer_genid = rt_peer_genid(); - } -} - static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie) { struct rtable *rt = (struct rtable *) dst; if (rt_is_expired(rt)) return NULL; - ipv4_validate_peer(rt); return dst; } @@ -1728,11 +1628,8 @@ static void ipv4_link_failure(struct sk_buff *skb) icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0); rt = skb_rtable(skb); - if (rt && rt_has_peer(rt)) { - struct inet_peer *peer = rt_peer_ptr(rt); - if (peer_pmtu_cleaned(peer)) - dst_metric_set(&rt->dst, RTAX_MTU, peer->pmtu_orig); - } + if (rt) + dst_set_expires(&rt->dst, 0); } static int ip_rt_bug(struct sk_buff *skb) @@ -1812,7 +1709,13 @@ static unsigned int ipv4_default_advmss(const struct dst_entry *dst) static unsigned int ipv4_mtu(const struct dst_entry *dst) { const struct rtable *rt = (const struct rtable *) dst; - unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); + unsigned int mtu = rt->rt_pmtu; + + if (mtu && time_after_eq(jiffies, rt->dst.expires)) + mtu = 0; + + if (!mtu) + mtu = dst_metric_raw(dst, RTAX_MTU); if (mtu && rt_is_output_route(rt)) return mtu; @@ -1843,19 +1746,10 @@ static void rt_init_metrics(struct rtable *rt, const struct flowi4 *fl4, peer = inet_getpeer_v4(base, rt->rt_dst, 0); if (peer) { __rt_set_peer(rt, peer); - rt->rt_peer_genid = rt_peer_genid(); if (inet_metrics_new(peer)) memcpy(peer->metrics, fi->fib_metrics, sizeof(u32) * RTAX_MAX); dst_init_metrics(&rt->dst, peer->metrics, false); - - check_peer_pmtu(&rt->dst, peer); - - if (peer->redirect_learned.a4 && - peer->redirect_learned.a4 != rt->rt_gateway) { - rt->rt_gateway = peer->redirect_learned.a4; - rt->rt_flags |= RTCF_REDIRECTED; - } } else { if (fi->fib_metrics != (u32 *) dst_default_metrics) { rt->fi = fi; @@ -1955,8 +1849,8 @@ static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr, rth->rt_iif = dev->ifindex; rth->rt_oif = 0; rth->rt_mark = skb->mark; + rth->rt_pmtu = 0; rth->rt_gateway = daddr; - rth->rt_peer_genid = 0; rt_init_peer(rth, dev_net(dev)->ipv4.peers); rth->fi = NULL; if (our) { @@ -2081,8 +1975,8 @@ static int __mkroute_input(struct sk_buff *skb, rth->rt_iif = in_dev->dev->ifindex; rth->rt_oif = 0; rth->rt_mark = skb->mark; + rth->rt_pmtu = 0; rth->rt_gateway = daddr; - rth->rt_peer_genid = 0; rt_init_peer(rth, &res->table->tb_peers); rth->fi = NULL; @@ -2260,8 +2154,8 @@ local_input: rth->rt_iif = dev->ifindex; rth->rt_oif = 0; rth->rt_mark = skb->mark; + rth->rt_pmtu = 0; rth->rt_gateway = daddr; - rth->rt_peer_genid = 0; rt_init_peer(rth, net->ipv4.peers); rth->fi = NULL; if (res.type == RTN_UNREACHABLE) { @@ -2337,7 +2231,6 @@ int ip_route_input_common(struct sk_buff *skb, __be32 daddr, __be32 saddr, rth->rt_mark == skb->mark && net_eq(dev_net(rth->dst.dev), net) && !rt_is_expired(rth)) { - ipv4_validate_peer(rth); if (noref) { dst_use_noref(&rth->dst, jiffies); skb_dst_set_noref(skb, &rth->dst); @@ -2459,8 +2352,8 @@ static struct rtable *__mkroute_output(const struct fib_result *res, rth->rt_iif = orig_oif ? : dev_out->ifindex; rth->rt_oif = orig_oif; rth->rt_mark = fl4->flowi4_mark; + rth->rt_pmtu = 0; rth->rt_gateway = fl4->daddr; - rth->rt_peer_genid = 0; rt_init_peer(rth, (res->table ? &res->table->tb_peers : dev_net(dev_out)->ipv4.peers)); @@ -2717,7 +2610,6 @@ struct rtable *__ip_route_output_key(struct net *net, struct flowi4 *flp4) (IPTOS_RT_MASK | RTO_ONLINK)) && net_eq(dev_net(rth->dst.dev), net) && !rt_is_expired(rth)) { - ipv4_validate_peer(rth); dst_use(&rth->dst, jiffies); RT_CACHE_STAT_INC(out_hit); rcu_read_unlock_bh(); @@ -2794,6 +2686,7 @@ struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_or rt->rt_iif = ort->rt_iif; rt->rt_oif = ort->rt_oif; rt->rt_mark = ort->rt_mark; + rt->rt_pmtu = ort->rt_pmtu; rt->rt_genid = rt_genid(net); rt->rt_flags = ort->rt_flags; @@ -2896,13 +2789,13 @@ static int rt_fill_info(struct net *net, const struct inet_peer *peer = rt_peer_ptr(rt); inet_peer_refcheck(peer); id = atomic_read(&peer->ip_id_count) & 0xffff; - expires = ACCESS_ONCE(peer->pmtu_expires); - if (expires) { - if (time_before(jiffies, expires)) - expires -= jiffies; - else - expires = 0; - } + } + expires = rt->dst.expires; + if (expires) { + if (time_before(jiffies, expires)) + expires -= jiffies; + else + expires = 0; } if (rt_is_input_route(rt)) { diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c index 9815ea0bca7f..951bcf35b21c 100644 --- a/net/ipv4/xfrm4_policy.c +++ b/net/ipv4/xfrm4_policy.c @@ -100,6 +100,7 @@ static int xfrm4_fill_dst(struct xfrm_dst *xdst, struct net_device *dev, xdst->u.rt.rt_src = rt->rt_src; xdst->u.rt.rt_dst = rt->rt_dst; xdst->u.rt.rt_gateway = rt->rt_gateway; + xdst->u.rt.rt_pmtu = rt->rt_pmtu; return 0; } -- 2.30.2