tipc: add new functions for multicast and broadcast distribution

We add a new broadcast link transmit function in bclink.c and a new
receive function in socket.c. The purpose is to move the branching
between external and internal destination down to the link layer,
just as we have done with unicast in earlier commits. We also make
use of the new link-independent fragmentation support that was
introduced in an earlier commit series.

This gives a shorter and simpler code path, and makes it possible
to obtain copy-free buffer delivery to all node local destination
sockets.

The new transmission code is added in parallel with the existing one,
and will be used by the socket multicast send function in the next
commit in this series.

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

1 files changed, 54 insertions, 1 deletions

diff --git a/net/tipc/bcast.c b/net/tipc/bcast.c
index 55c6c9d3e1ce..ac947251dd37 100644
--- a/net/tipc/bcast.c
+++ b/net/tipc/bcast.c
@@ -1,7 +1,7 @@
 /*
  * net/tipc/bcast.c: TIPC broadcast code
  *
- * Copyright (c) 2004-2006, Ericsson AB
+ * Copyright (c) 2004-2006, 2014, Ericsson AB
  * Copyright (c) 2004, Intel Corporation.
  * Copyright (c) 2005, 2010-2011, Wind River Systems
  * All rights reserved.
@@ -38,6 +38,8 @@
 #include "core.h"
 #include "link.h"
 #include "port.h"
+#include "socket.h"
+#include "msg.h"
 #include "bcast.h"
 #include "name_distr.h"
 
@@ -138,6 +140,11 @@ static void tipc_bclink_unlock(void)
 		tipc_link_reset_all(node);
 }
 
+uint  tipc_bclink_get_mtu(void)
+{
+	return MAX_PKT_DEFAULT_MCAST;
+}
+
 void tipc_bclink_set_flags(unsigned int flags)
 {
 	bclink->flags |= flags;
@@ -408,6 +415,52 @@ exit:
 	return res;
 }
 
+/* tipc_bclink_xmit2 - broadcast buffer chain to all nodes in cluster
+ *                     and to identified node local sockets
+ * @buf: chain of buffers containing message
+ * Consumes the buffer chain, except when returning -ELINKCONG
+ * Returns 0 if success, otherwise errno: -ELINKCONG,-EHOSTUNREACH,-EMSGSIZE
+ */
+int tipc_bclink_xmit2(struct sk_buff *buf)
+{
+	int rc = 0;
+	int bc = 0;
+	struct sk_buff *clbuf;
+
+	/* Prepare clone of message for local node */
+	clbuf = tipc_msg_reassemble(buf);
+	if (unlikely(!clbuf)) {
+		kfree_skb_list(buf);
+		return -EHOSTUNREACH;
+	}
+
+	/* Broadcast to all other nodes */
+	if (likely(bclink)) {
+		tipc_bclink_lock();
+		if (likely(bclink->bcast_nodes.count)) {
+			rc = __tipc_link_xmit(bcl, buf);
+			if (likely(!rc)) {
+				bclink_set_last_sent();
+				bcl->stats.queue_sz_counts++;
+				bcl->stats.accu_queue_sz += bcl->out_queue_size;
+			}
+			bc = 1;
+		}
+		tipc_bclink_unlock();
+	}
+
+	if (unlikely(!bc))
+		kfree_skb_list(buf);
+
+	/* Deliver message clone */
+	if (likely(!rc))
+		tipc_sk_mcast_rcv(clbuf);
+	else
+		kfree_skb(clbuf);
+
+	return rc;
+}
+
 /**
  * bclink_accept_pkt - accept an incoming, in-sequence broadcast packet
  *