tipc: use explicit allocation of broadcast send link The broadcast link instance (struct tipc_link) used for sending is currently aggregated into struct tipc_bclink. This means that we cannot use the regular tipc_link_create() function for initiating the link, but do instead have to initiate numerous fields directly from the bcast_init() function. We want to reduce dependencies between the broadcast functionality and the inner workings of tipc_link. In this commit, we introduce a new function tipc_bclink_create() to link.c, and allocate the instance of the link separately using this function. Signed-off-by: Jon Maloy <[email protected]> Reviewed-by: Ying Xue <[email protected]> Signed-off-by: David S. Miller <[email protected]>

diff --git a/net/tipc/link.c b/net/tipc/link.c
index 0d8fdc8..f0cf768 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c

@@ -50,6 +50,7 @@
  */
 static const char *link_co_err = "Link tunneling error, ";
 static const char *link_rst_msg = "Resetting link ";
+static const char tipc_bclink_name[] = "broadcast-link";
 
 static const struct nla_policy tipc_nl_link_policy[TIPC_NLA_LINK_MAX + 1] = {
 	[TIPC_NLA_LINK_UNSPEC]		= { .type = NLA_UNSPEC },
@@ -231,6 +232,34 @@
 	return true;
 }
 
+/**
+ * tipc_link_bc_create - create new link to be used for broadcast
+ * @n: pointer to associated node
+ * @mtu: mtu to be used
+ * @window: send window to be used
+ * @inputq: queue to put messages ready for delivery
+ * @namedq: queue to put binding table update messages ready for delivery
+ * @link: return value, pointer to put the created link
+ *
+ * Returns true if link was created, otherwise false
+ */
+bool tipc_link_bc_create(struct tipc_node *n, int mtu, int window,
+			 struct sk_buff_head *inputq,
+			 struct sk_buff_head *namedq,
+			 struct tipc_link **link)
+{
+	struct tipc_link *l;
+
+	if (!tipc_link_create(n, "", MAX_BEARERS, 0, 'Z', mtu, 0, window,
+			      0, 0, 0, NULL, inputq, namedq, link))
+		return false;
+
+	l = *link;
+	strcpy(l->name, tipc_bclink_name);
+	tipc_link_reset(l);
+	return true;
+}
+
 /* tipc_link_build_bcast_sync_msg() - synchronize broadcast link endpoints.
  *
  * Give a newly added peer node the sequence number where it should