tipc: update replicast capability for broadcast send link

When setting up a cluster with non-replicast/replicast capability
supported. This capability will be disabled for broadcast send link
in order to be backwards compatible.

However, when these non-support nodes left and be removed out the cluster.
We don't update this capability on broadcast send link. Then, some of
features that based on this capability will also disabling as unexpected.

In this commit, we make sure the broadcast send link capabilities will
be re-calculated as soon as a node removed/rejoined a cluster.

Acked-by: Jon Maloy <[e-mail]>
Signed-off-by: Hoang Le <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

net/tipc/bcast.c

···
 	return tipc_link_mss(tipc_bc_sndlink(net));
 }
 
-void tipc_bcast_disable_rcast(struct net *net)
+void tipc_bcast_toggle_rcast(struct net *net, bool supp)
 {
-	tipc_bc_base(net)->rcast_support = false;
+	tipc_bc_base(net)->rcast_support = supp;
 }
 
 static void tipc_bcbase_calc_bc_threshold(struct net *net)

net/tipc/bcast.h

···
 void tipc_bcast_inc_bearer_dst_cnt(struct net *net, int bearer_id);
 void tipc_bcast_dec_bearer_dst_cnt(struct net *net, int bearer_id);
 int  tipc_bcast_get_mtu(struct net *net);
-void tipc_bcast_disable_rcast(struct net *net);
+void tipc_bcast_toggle_rcast(struct net *net, bool supp);
 int tipc_mcast_xmit(struct net *net, struct sk_buff_head *pkts,
 		    struct tipc_mc_method *method, struct tipc_nlist *dests,
 		    u16 *cong_link_cnt);

net/tipc/link.c

···
 
 	/* Disable replicast if even a single peer doesn't support it */
 	if (link_is_bc_rcvlink(l) && !(peer_caps & TIPC_BCAST_RCAST))
-		tipc_bcast_disable_rcast(net);
+		tipc_bcast_toggle_rcast(net, false);
 
 	return true;
 }

net/tipc/node.c

···
 			tn->capabilities &= temp_node->capabilities;
 		}
 
+		tipc_bcast_toggle_rcast(net,
+					(tn->capabilities & TIPC_BCAST_RCAST));
+
 		goto exit;
 	}
 	n = kzalloc(sizeof(*n), GFP_ATOMIC);
···
 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
 		tn->capabilities &= temp_node->capabilities;
 	}
+	tipc_bcast_toggle_rcast(net, (tn->capabilities & TIPC_BCAST_RCAST));
 	trace_tipc_node_create(n, true, " ");
 exit:
 	spin_unlock_bh(&tn->node_list_lock);
···
 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
 		tn->capabilities &= temp_node->capabilities;
 	}
-
+	tipc_bcast_toggle_rcast(peer->net,
+				(tn->capabilities & TIPC_BCAST_RCAST));
 	spin_unlock_bh(&tn->node_list_lock);
 	return deleted;
 }
···
 	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
 		tn->capabilities &= temp_node->capabilities;
 	}
+	tipc_bcast_toggle_rcast(net, (tn->capabilities & TIPC_BCAST_RCAST));
 	err = 0;
 err_out:
 	tipc_node_put(peer);