tipc: simplify bearer level broadcast

Until now, we have been keeping track of the exact set of broadcast
destinations though the help structure tipc_node_map. This leads us to
have to maintain a whole infrastructure for supporting this, including
a pseudo-bearer and a number of functions to manipulate both the bearers
and the node map correctly. Apart from the complexity, this approach is
also limiting, as struct tipc_node_map only can support cluster local
broadcast if we want to avoid it becoming excessively large. We want to
eliminate this limitation, in order to enable introduction of scoped
multicast in the future.

A closer analysis reveals that it is unnecessary maintaining this "full
set" overview; it is sufficient to keep a counter per bearer, indicating
how many nodes can be reached via this bearer at the moment. The protocol
is now robust enough to handle transitional discrepancies between the
nominal number of reachable destinations, as expected by the broadcast
protocol itself, and the number which is actually reachable at the
moment. The initial broadcast synchronization, in conjunction with the
retransmission mechanism, ensures that all packets will eventually be
acknowledged by the correct set of destinations.

This commit introduces these changes.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 4 deletions

diff --git a/net/tipc/bcast.h b/net/tipc/bcast.h
index 568a57cd89e6..76b747a73b0b 100644
--- a/net/tipc/bcast.h
+++ b/net/tipc/bcast.h
@@ -47,11 +47,11 @@ struct tipc_node_map;
 int tipc_bcast_init(struct net *net);
 void tipc_bcast_reinit(struct net *net);
 void tipc_bcast_stop(struct net *net);
-void tipc_bcast_add_peer(struct net *net, u32 addr,
-			 struct tipc_link *l,
+void tipc_bcast_add_peer(struct net *net, struct tipc_link *l,
 			 struct sk_buff_head *xmitq);
-void tipc_bcast_remove_peer(struct net *net, u32 addr,
-			    struct tipc_link *rcv_bcl);
+void tipc_bcast_remove_peer(struct net *net, struct tipc_link *rcv_bcl);
+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);
 struct tipc_node *tipc_bclink_retransmit_to(struct net *tn);
 void tipc_bclink_acknowledge(struct tipc_node *n_ptr, u32 acked);
 void tipc_bclink_rcv(struct net *net, struct sk_buff *buf);