[NETNS]: Add the netns_ipv4 struct

The ipv4 will store its parameters inside this structure.
This one is empty now, but it will be eventually filled.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/net_namespace.h

@@ -10,6 +10,7 @@
 
 #include <net/netns/unix.h>
 #include <net/netns/packet.h>
+#include <net/netns/ipv4.h>
 
 struct proc_dir_entry;
 struct net_device;
@@ -46,6 +47,7 @@ struct net {
 
 	struct netns_packet	packet;
 	struct netns_unix	unx;
+	struct netns_ipv4	ipv4;
 };
 
 #ifdef CONFIG_NET

include/net/netns/ipv4.h

@@ -0,0 +1,9 @@
+/*
+ * ipv4 in net namespaces
+ */
+
+#ifndef __NETNS_IPV4_H__
+#define __NETNS_IPV4_H__
+struct netns_ipv4 {
+};
+#endif