net: ppp_generic - introduce net-namespace functionality v2

- Each namespace contains ppp channels and units separately
  with appropriate locks
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/ppp_channel.h

@@ -22,6 +22,7 @@
 #include <linux/list.h>
 #include <linux/skbuff.h>
 #include <linux/poll.h>
+#include <net/net_namespace.h>
 
 struct ppp_channel;
 
@@ -56,6 +57,9 @@ extern void ppp_input(struct ppp_channel *, struct sk_buff *);
    that we may have missed a packet. */
 extern void ppp_input_error(struct ppp_channel *, int code);
 
+/* Attach a channel to a given PPP unit in specified net. */
+extern int ppp_register_net_channel(struct net *, struct ppp_channel *);
+
 /* Attach a channel to a given PPP unit. */
 extern int ppp_register_channel(struct ppp_channel *);