ipv6: Move gateway checks to a fib6_nh setting

The gateway setting is not per fib6_info entry but per-fib6_nh. Add a new
fib_nh_has_gw flag to fib6_nh and convert references to RTF_GATEWAY to
the new flag. For IPv6 address the flag is cheaper than checking that
nh_gw is non-0 like IPv4 does.

While this increases fib6_nh by 8-bytes, the effective allocation size of
a fib6_info is unchanged. The 8 bytes is recovered later with a
fib_nh_common change.

Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 13 insertions, 12 deletions

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 4ae17a966ae3..c5ac08fc6cc9 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -173,7 +173,8 @@ static int addrconf_ifdown(struct net_device *dev, int how);
 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
 						  int plen,
 						  const struct net_device *dev,
-						  u32 flags, u32 noflags);
+						  u32 flags, u32 noflags,
+						  bool no_gw);
 
 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
 static void addrconf_dad_work(struct work_struct *w);
@@ -1230,10 +1231,8 @@ cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires, bool del_r
 {
 	struct fib6_info *f6i;
 
-	f6i = addrconf_get_prefix_route(&ifp->addr,
-				       ifp->prefix_len,
-				       ifp->idev->dev,
-				       0, RTF_GATEWAY | RTF_DEFAULT);
+	f6i = addrconf_get_prefix_route(&ifp->addr, ifp->prefix_len,
+					ifp->idev->dev, 0, RTF_DEFAULT, true);
 	if (f6i) {
 		if (del_rt)
 			ip6_del_rt(dev_net(ifp->idev->dev), f6i);
@@ -2402,7 +2401,8 @@ addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
 						  int plen,
 						  const struct net_device *dev,
-						  u32 flags, u32 noflags)
+						  u32 flags, u32 noflags,
+						  bool no_gw)
 {
 	struct fib6_node *fn;
 	struct fib6_info *rt = NULL;
@@ -2421,6 +2421,8 @@ static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
 	for_each_fib6_node_rt_rcu(fn) {
 		if (rt->fib6_nh.nh_dev->ifindex != dev->ifindex)
 			continue;
+		if (no_gw && rt->fib6_nh.fib_nh_has_gw)
+			continue;
 		if ((rt->fib6_flags & flags) != flags)
 			continue;
 		if ((rt->fib6_flags & noflags) != 0)
@@ -2717,7 +2719,7 @@ void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
 					       pinfo->prefix_len,
 					       dev,
 					       RTF_ADDRCONF | RTF_PREFIX_RT,
-					       RTF_GATEWAY | RTF_DEFAULT);
+					       RTF_DEFAULT, true);
 
 		if (rt) {
 			/* Autoconf prefix route */
@@ -4588,10 +4590,8 @@ static int modify_prefix_route(struct inet6_ifaddr *ifp,
 	struct fib6_info *f6i;
 	u32 prio;
 
-	f6i = addrconf_get_prefix_route(&ifp->addr,
-					ifp->prefix_len,
-					ifp->idev->dev,
-					0, RTF_GATEWAY | RTF_DEFAULT);
+	f6i = addrconf_get_prefix_route(&ifp->addr, ifp->prefix_len,
+					ifp->idev->dev, 0, RTF_DEFAULT, true);
 	if (!f6i)
 		return -ENOENT;
 
@@ -5972,7 +5972,8 @@ static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
 			struct fib6_info *rt;
 
 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
-						       ifp->idev->dev, 0, 0);
+						       ifp->idev->dev, 0, 0,
+						       false);
 			if (rt)
 				ip6_del_rt(net, rt);
 		}