From 21efcfa0ff27776902a8a15e810147be4d937d69 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 19 Jul 2011 20:18:36 +0000 Subject: ipv6: unshare inetpeers We currently cow metrics a bit too soon in IPv6 case : All routes are tied to a single inetpeer entry. Change ip6_rt_copy() to get destination address as second argument, so that we fill rt6i_dst before the dst_copy_metrics() call. icmp6_dst_alloc() must set rt6i_dst before calling dst_metric_set(), or else the cow is done while rt6i_dst is still NULL. If orig route points to readonly metrics, we can share the pointer instead of performing the memory allocation and copy. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/ipv6/route.c | 33 ++++++++++++++++++++------------- 1 file changed, 20 insertions(+), 13 deletions(-) (limited to 'net') diff --git a/net/ipv6/route.c b/net/ipv6/route.c index ddef80f568b0..e8987da06667 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -72,7 +72,8 @@ #define RT6_TRACE(x...) do { ; } while (0) #endif -static struct rt6_info * ip6_rt_copy(struct rt6_info *ort); +static struct rt6_info *ip6_rt_copy(const struct rt6_info *ort, + const struct in6_addr *dest); static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie); static unsigned int ip6_default_advmss(const struct dst_entry *dst); static unsigned int ip6_default_mtu(const struct dst_entry *dst); @@ -690,7 +691,8 @@ int ip6_ins_rt(struct rt6_info *rt) return __ip6_ins_rt(rt, &info); } -static struct rt6_info *rt6_alloc_cow(struct rt6_info *ort, const struct in6_addr *daddr, +static struct rt6_info *rt6_alloc_cow(const struct rt6_info *ort, + const struct in6_addr *daddr, const struct in6_addr *saddr) { struct rt6_info *rt; @@ -699,7 +701,7 @@ static struct rt6_info *rt6_alloc_cow(struct rt6_info *ort, const struct in6_add * Clone the route. */ - rt = ip6_rt_copy(ort); + rt = ip6_rt_copy(ort, daddr); if (rt) { struct neighbour *neigh; @@ -707,12 +709,11 @@ static struct rt6_info *rt6_alloc_cow(struct rt6_info *ort, const struct in6_add if (!(rt->rt6i_flags&RTF_GATEWAY)) { if (rt->rt6i_dst.plen != 128 && - ipv6_addr_equal(&rt->rt6i_dst.addr, daddr)) + ipv6_addr_equal(&ort->rt6i_dst.addr, daddr)) rt->rt6i_flags |= RTF_ANYCAST; ipv6_addr_copy(&rt->rt6i_gateway, daddr); } - ipv6_addr_copy(&rt->rt6i_dst.addr, daddr); rt->rt6i_dst.plen = 128; rt->rt6i_flags |= RTF_CACHE; rt->dst.flags |= DST_HOST; @@ -759,11 +760,12 @@ static struct rt6_info *rt6_alloc_cow(struct rt6_info *ort, const struct in6_add return rt; } -static struct rt6_info *rt6_alloc_clone(struct rt6_info *ort, const struct in6_addr *daddr) +static struct rt6_info *rt6_alloc_clone(struct rt6_info *ort, + const struct in6_addr *daddr) { - struct rt6_info *rt = ip6_rt_copy(ort); + struct rt6_info *rt = ip6_rt_copy(ort, daddr); + if (rt) { - ipv6_addr_copy(&rt->rt6i_dst.addr, daddr); rt->rt6i_dst.plen = 128; rt->rt6i_flags |= RTF_CACHE; rt->dst.flags |= DST_HOST; @@ -907,7 +909,10 @@ struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_ori new->input = dst_discard; new->output = dst_discard; - dst_copy_metrics(new, &ort->dst); + if (dst_metrics_read_only(&ort->dst)) + new->_metrics = ort->dst._metrics; + else + dst_copy_metrics(new, &ort->dst); rt->rt6i_idev = ort->rt6i_idev; if (rt->rt6i_idev) in6_dev_hold(rt->rt6i_idev); @@ -1067,6 +1072,7 @@ struct dst_entry *icmp6_dst_alloc(struct net_device *dev, rt->rt6i_idev = idev; dst_set_neighbour(&rt->dst, neigh); atomic_set(&rt->dst.__refcnt, 1); + ipv6_addr_copy(&rt->rt6i_dst.addr, addr); dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 255); rt->dst.output = ip6_output; @@ -1584,7 +1590,7 @@ void rt6_redirect(const struct in6_addr *dest, const struct in6_addr *src, if (neigh == dst_get_neighbour(&rt->dst)) goto out; - nrt = ip6_rt_copy(rt); + nrt = ip6_rt_copy(rt, dest); if (nrt == NULL) goto out; @@ -1592,7 +1598,6 @@ void rt6_redirect(const struct in6_addr *dest, const struct in6_addr *src, if (on_link) nrt->rt6i_flags &= ~RTF_GATEWAY; - ipv6_addr_copy(&nrt->rt6i_dst.addr, dest); nrt->rt6i_dst.plen = 128; nrt->dst.flags |= DST_HOST; @@ -1730,7 +1735,8 @@ void rt6_pmtu_discovery(const struct in6_addr *daddr, const struct in6_addr *sad * Misc support functions */ -static struct rt6_info * ip6_rt_copy(struct rt6_info *ort) +static struct rt6_info *ip6_rt_copy(const struct rt6_info *ort, + const struct in6_addr *dest) { struct net *net = dev_net(ort->rt6i_dev); struct rt6_info *rt = ip6_dst_alloc(&net->ipv6.ip6_dst_ops, @@ -1740,6 +1746,8 @@ static struct rt6_info * ip6_rt_copy(struct rt6_info *ort) rt->dst.input = ort->dst.input; rt->dst.output = ort->dst.output; + ipv6_addr_copy(&rt->rt6i_dst.addr, dest); + rt->rt6i_dst.plen = ort->rt6i_dst.plen; dst_copy_metrics(&rt->dst, &ort->dst); rt->dst.error = ort->dst.error; rt->rt6i_idev = ort->rt6i_idev; @@ -1752,7 +1760,6 @@ static struct rt6_info * ip6_rt_copy(struct rt6_info *ort) rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES; rt->rt6i_metric = 0; - memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key)); #ifdef CONFIG_IPV6_SUBTREES memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key)); #endif -- cgit v1.2.3-59-g8ed1b