[GENETLINK]: Add cmd dump completion.

Remove assumption that generic netlink commands cannot have dump
completion callbacks.
Signed-off-by: NJamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/net/genetlink.h

@@ -53,6 +53,7 @@ struct genl_info
  * @policy: attribute validation policy
  * @doit: standard command callback
  * @dumpit: callback for dumpers
+ * @done: completion callback for dumps
  * @ops_list: operations list
  */
 struct genl_ops
@@ -64,6 +65,7 @@ struct genl_ops
 				       struct genl_info *info);
 	int		       (*dumpit)(struct sk_buff *skb,
 					 struct netlink_callback *cb);
+	int		       (*done)(struct netlink_callback *cb);
 	struct list_head	ops_list;
 };
 

net/netlink/genetlink.c

@@ -331,7 +331,7 @@ static int genl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
 		}
 
 		*errp = err = netlink_dump_start(genl_sock, skb, nlh,
-						 ops->dumpit, NULL);
+						 ops->dumpit, ops->done);
 		if (err == 0)
 			skb_pull(skb, min(NLMSG_ALIGN(nlh->nlmsg_len),
 					  skb->len));