ipv4: Move IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN to helper

in_dev lookup followed by IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN check
is called in several places, some with the rcu lock and others with the
rtnl held.

Move the check to a helper similar to what IPv6 has. Since the helper
can be invoked from either context use rcu_dereference_rtnl to
dereference ip_ptr.

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

diff --git a/include/linux/inetdevice.h b/include/linux/inetdevice.h
index a64f21a..367dc2a 100644 (file)
--- a/include/linux/inetdevice.h
+++ b/include/linux/inetdevice.h
@@ -237,6 +237,20 @@ static inline struct in_device *__in_dev_get_rtnl(const struct net_device *dev)
        return rtnl_dereference(dev->ip_ptr);
 }
 
+/* called with rcu_read_lock or rtnl held */
+static inline bool ip_ignore_linkdown(const struct net_device *dev)
+{
+       struct in_device *in_dev;
+       bool rc = false;
+
+       in_dev = rcu_dereference_rtnl(dev->ip_ptr);
+       if (in_dev &&
+           IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN(in_dev))
+               rc = true;
+
+       return rc;
+}
+
 static inline struct neigh_parms *__in_dev_arp_parms_get_rcu(const struct net_device *dev)
 {
        struct in_device *in_dev = __in_dev_get_rcu(dev);

diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
index b5dbbdf..78631eb 100644 (file)
--- a/net/ipv4/fib_semantics.c
+++ b/net/ipv4/fib_semantics.c
@@ -558,7 +558,6 @@ static void fib_rebalance(struct fib_info *fi)
 {
        int total;
        int w;
-       struct in_device *in_dev;
 
        if (fi->fib_nhs < 2)
                return;
@@ -568,10 +567,7 @@ static void fib_rebalance(struct fib_info *fi)
                if (nh->nh_flags & RTNH_F_DEAD)
                        continue;
 
-               in_dev = __in_dev_get_rtnl(nh->nh_dev);
-
-               if (in_dev &&
-                   IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN(in_dev) &&
+               if (ip_ignore_linkdown(nh->nh_dev) &&
                    nh->nh_flags & RTNH_F_LINKDOWN)
                        continue;
 
@@ -582,12 +578,9 @@ static void fib_rebalance(struct fib_info *fi)
        change_nexthops(fi) {
                int upper_bound;
 
-               in_dev = __in_dev_get_rtnl(nexthop_nh->nh_dev);
-
                if (nexthop_nh->nh_flags & RTNH_F_DEAD) {
                        upper_bound = -1;
-               } else if (in_dev &&
-                          IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN(in_dev) &&
+               } else if (ip_ignore_linkdown(nexthop_nh->nh_dev) &&
                           nexthop_nh->nh_flags & RTNH_F_LINKDOWN) {
                        upper_bound = -1;
                } else {
@@ -1325,12 +1318,8 @@ int fib_dump_info(struct sk_buff *skb, u32 portid, u32 seq, int event,
                    nla_put_u32(skb, RTA_OIF, fi->fib_nh->nh_oif))
                        goto nla_put_failure;
                if (fi->fib_nh->nh_flags & RTNH_F_LINKDOWN) {
-                       struct in_device *in_dev;
-
                        rcu_read_lock();
-                       in_dev = __in_dev_get_rcu(fi->fib_nh->nh_dev);
-                       if (in_dev &&
-                           IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN(in_dev))
+                       if (ip_ignore_linkdown(fi->fib_nh->nh_dev))
                                rtm->rtm_flags |= RTNH_F_DEAD;
                        rcu_read_unlock();
                }
@@ -1361,12 +1350,8 @@ int fib_dump_info(struct sk_buff *skb, u32 portid, u32 seq, int event,
 
                        rtnh->rtnh_flags = nh->nh_flags & 0xFF;
                        if (nh->nh_flags & RTNH_F_LINKDOWN) {
-                               struct in_device *in_dev;
-
                                rcu_read_lock();
-                               in_dev = __in_dev_get_rcu(nh->nh_dev);
-                               if (in_dev &&
-                                   IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN(in_dev))
+                               if (ip_ignore_linkdown(nh->nh_dev))
                                        rtnh->rtnh_flags |= RTNH_F_DEAD;
                                rcu_read_unlock();
                        }
@@ -1433,7 +1418,7 @@ int fib_sync_down_addr(struct net_device *dev, __be32 local)
 static int call_fib_nh_notifiers(struct fib_nh *fib_nh,
                                 enum fib_event_type event_type)
 {
-       struct in_device *in_dev = __in_dev_get_rtnl(fib_nh->nh_dev);
+       bool ignore_link_down = ip_ignore_linkdown(fib_nh->nh_dev);
        struct fib_nh_notifier_info info = {
                .fib_nh = fib_nh,
        };
@@ -1442,14 +1427,12 @@ static int call_fib_nh_notifiers(struct fib_nh *fib_nh,
        case FIB_EVENT_NH_ADD:
                if (fib_nh->nh_flags & RTNH_F_DEAD)
                        break;
-               if (IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN(in_dev) &&
-                   fib_nh->nh_flags & RTNH_F_LINKDOWN)
+               if (ignore_link_down && fib_nh->nh_flags & RTNH_F_LINKDOWN)
                        break;
                return call_fib4_notifiers(dev_net(fib_nh->nh_dev), event_type,
                                           &info.info);
        case FIB_EVENT_NH_DEL:
-               if ((in_dev && IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN(in_dev) &&
-                    fib_nh->nh_flags & RTNH_F_LINKDOWN) ||
+               if ((ignore_link_down && fib_nh->nh_flags & RTNH_F_LINKDOWN) ||
                    (fib_nh->nh_flags & RTNH_F_DEAD))
                        return call_fib4_notifiers(dev_net(fib_nh->nh_dev),
                                                   event_type, &info.info);

diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c
index 1704f43..656d3d1 100644 (file)
--- a/net/ipv4/fib_trie.c
+++ b/net/ipv4/fib_trie.c
@@ -1471,12 +1471,10 @@ found:
                        continue;
                for (nhsel = 0; nhsel < fi->fib_nhs; nhsel++) {
                        const struct fib_nh *nh = &fi->fib_nh[nhsel];
-                       struct in_device *in_dev = __in_dev_get_rcu(nh->nh_dev);
 
                        if (nh->nh_flags & RTNH_F_DEAD)
                                continue;
-                       if (in_dev &&
-                           IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN(in_dev) &&
+                       if (ip_ignore_linkdown(nh->nh_dev) &&
                            nh->nh_flags & RTNH_F_LINKDOWN &&
                            !(fib_flags & FIB_LOOKUP_IGNORE_LINKSTATE))
                                continue;