ipv4: Rename and export nh_update_mtu

Rename nh_update_mtu to fib_nhc_update_mtu and export for use by the
nexthop code.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/ip_fib.h

@@ -432,6 +432,7 @@ int fib_sync_down_dev(struct net_device *dev, unsigned long event, bool force);
 int fib_sync_down_addr(struct net_device *dev, __be32 local);
 int fib_sync_up(struct net_device *dev, unsigned char nh_flags);
 void fib_sync_mtu(struct net_device *dev, u32 orig_mtu);
+void fib_nhc_update_mtu(struct fib_nh_common *nhc, u32 new, u32 orig);
 
 #ifdef CONFIG_IP_ROUTE_MULTIPATH
 int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4,

net/ipv4/fib_semantics.c

@@ -1712,7 +1712,7 @@ static int call_fib_nh_notifiers(struct fib_nh *nh,
  * - if the new MTU is greater than the PMTU, don't make any change
  * - otherwise, unlock and set PMTU
  */
-static void nh_update_mtu(struct fib_nh_common *nhc, u32 new, u32 orig)
+void fib_nhc_update_mtu(struct fib_nh_common *nhc, u32 new, u32 orig)
 {
 	struct fnhe_hash_bucket *bucket;
 	int i;
@@ -1748,7 +1748,7 @@ void fib_sync_mtu(struct net_device *dev, u32 orig_mtu)
 
 	hlist_for_each_entry(nh, head, nh_hash) {
 		if (nh->fib_nh_dev == dev)
-			nh_update_mtu(&nh->nh_common, dev->mtu, orig_mtu);
+			fib_nhc_update_mtu(&nh->nh_common, dev->mtu, orig_mtu);
 	}
 }