[NETNS][IPV6]: Add ipv6 structure for netns.

Like the ipv4 part, this patch adds an ipv6 structure in the net
structure to aggregate the different resources to make ipv6 per
namespace.

Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h
index d04ddf2..b0a5f90 100644
--- a/include/net/net_namespace.h
+++ b/include/net/net_namespace.h
@@ -11,6 +11,7 @@
 #include <net/netns/unix.h>
 #include <net/netns/packet.h>
 #include <net/netns/ipv4.h>
+#include <net/netns/ipv6.h>
 
 struct proc_dir_entry;
 struct net_device;
@@ -48,6 +49,9 @@
 	struct netns_packet	packet;
 	struct netns_unix	unx;
 	struct netns_ipv4	ipv4;
+#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+	struct netns_ipv6	ipv6;
+#endif
 };
 
 #ifdef CONFIG_NET
diff --git a/include/net/netns/ipv6.h b/include/net/netns/ipv6.h
new file mode 100644
index 0000000..6f82046
--- /dev/null
+++ b/include/net/netns/ipv6.h
@@ -0,0 +1,10 @@
+/*
+ * ipv6 in net namespaces
+ */
+
+#ifndef __NETNS_IPV6_H__
+#define __NETNS_IPV6_H__
+
+struct netns_ipv6 {
+};
+#endif