tipc: improve groupcast scope handling

When a member joins a group, it also indicates a binding scope. This
makes it possible to create both node local groups, invisible to other
nodes, as well as cluster global groups, visible everywhere.

In order to avoid that different members end up having permanently
differing views of group size and memberhip, we must inhibit locally
and globally bound members from joining the same group.

We do this by using the binding scope as an additional separator between
groups. I.e., a member must ignore all membership events from sockets
using a different scope than itself, and all lookups for message
destinations must require an exact match between the message's lookup
scope and the potential target's binding scope.

Apart from making it possible to create local groups using the same
identity on different nodes, a side effect of this is that it now also
becomes possible to create a cluster global group with the same identity
across the same nodes, without interfering with the local groups.

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

1 files changed, 2 insertions, 2 deletions

diff --git a/net/tipc/server.c b/net/tipc/server.c
index 950c54cbcf3a..8ee5e86b7870 100644
--- a/net/tipc/server.c
+++ b/net/tipc/server.c
@@ -489,8 +489,8 @@ void tipc_conn_terminate(struct tipc_server *s, int conid)
 	}
 }
 
-bool tipc_topsrv_kern_subscr(struct net *net, u32 port, u32 type,
-			     u32 filter, u32 lower, u32 upper, int *conid)
+bool tipc_topsrv_kern_subscr(struct net *net, u32 port, u32 type, u32 lower,
+			     u32 upper, u32 filter, int *conid)
 {
 	struct tipc_subscriber *scbr;
 	struct tipc_subscr sub;