net: Move void devices dumping in a separate helper

To make it look symmetrical to over types dumping.
And for simpler further patching.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

net.c

@@ -143,13 +143,34 @@ unk:
 	return -1;
 }
 
+static int dump_one_voiddev(struct ifinfomsg *ifi,
+		struct rtattr **tb, struct cr_fdset *fds)
+{
+	char *kind;
+
+	kind = link_kind(ifi, tb);
+	if (!kind)
+		goto unk;
+
+	if (!strcmp(kind, "venet"))
+		/*
+		 * If we meet a link we know about, such as
+		 * OpenVZ's venet, save general parameters of
+		 * it as external link.
+		 */
+		return dump_one_netdev(ND_TYPE__EXTLINK, ifi, tb, fds, NULL);
+
+unk:
+	pr_err("Unknown VOID kind %s link %d\n", kind, ifi->ifi_index);
+	return -1;
+}
+
 static int dump_one_link(struct nlmsghdr *hdr, void *arg)
 {
 	struct cr_fdset *fds = arg;
 	struct ifinfomsg *ifi;
 	int ret = 0, len = hdr->nlmsg_len - NLMSG_LENGTH(sizeof(*ifi));
 	struct rtattr *tb[IFLA_MAX + 1];
-	char *kind;
 
 	ifi = NLMSG_DATA(hdr);
 
@@ -173,17 +194,8 @@ static int dump_one_link(struct nlmsghdr *hdr, void *arg)
 		ret = dump_one_gendev(ifi, tb, fds);
 		break;
 	case ARPHRD_VOID:
-		/*
-		 * If we meet a link we know about, such as
-		 * OpenVZ's venet, save general parameters of
-		 * it as external link.
-		 */
-		kind = link_kind(ifi, tb);
-		if (kind && !strcmp(kind, "venet")) {
-			ret = dump_one_netdev(ND_TYPE__EXTLINK, ifi, tb, fds, NULL);
-			break;
-		}
-		/* Fall through otherwise! */
+		ret = dump_one_voiddev(ifi, tb, fds);
+		break;
 	default:
 		pr_err("Unsupported link type %d, kind %s\n",
 				ifi->ifi_type, link_kind(ifi, tb));