[NETNS][DST] dst: pass the dst_ops as parameter to the gc functions

The garbage collection function receive the dst_ops structure as
parameter. This is useful for the next incoming patchset because it
will need the dst_ops (there will be several instances) and the
network namespace pointer (contained in the dst_ops).

The protocols which do not take care of the namespaces will not be
impacted by this change (expect for the function signature), they do
just ignore the parameter.

Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index a429900..4004c5f 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -79,7 +79,7 @@
 static void		ip6_dst_destroy(struct dst_entry *);
 static void		ip6_dst_ifdown(struct dst_entry *,
 				       struct net_device *dev, int how);
-static int		 ip6_dst_gc(void);
+static int		 ip6_dst_gc(struct dst_ops *ops);
 
 static int		ip6_pkt_discard(struct sk_buff *skb);
 static int		ip6_pkt_discard_out(struct sk_buff *skb);
@@ -983,7 +983,7 @@
 	return freed;
 }
 
-static int ip6_dst_gc(void)
+static int ip6_dst_gc(struct dst_ops *ops)
 {
 	static unsigned expire = 30*HZ;
 	static unsigned long last_gc;