[TIPC] Initial merge

TIPC (Transparent Inter Process Communication) is a protocol designed for
intra cluster communication. For more information see
http://tipc.sourceforge.net

Signed-off-by: Per Liden <per.liden@nospam.ericsson.com>

48 files changed, 18191 insertions, 0 deletions

diff --git a/net/Kconfig b/net/Kconfig
index 60f6f321bd7..9296b269d67 100644
--- a/net/Kconfig
+++ b/net/Kconfig
@@ -159,6 +159,7 @@ source "net/ipx/Kconfig"
 source "drivers/net/appletalk/Kconfig"
 source "net/x25/Kconfig"
 source "net/lapb/Kconfig"
+source "net/tipc/Kconfig"
 
 config NET_DIVERT
 	bool "Frame Diverter (EXPERIMENTAL)"
diff --git a/net/Makefile b/net/Makefile
index f5141b9d4f3..065796f5fb1 100644
--- a/net/Makefile
+++ b/net/Makefile
@@ -45,6 +45,7 @@ obj-$(CONFIG_VLAN_8021Q)	+= 8021q/
 obj-$(CONFIG_IP_DCCP)		+= dccp/
 obj-$(CONFIG_IP_SCTP)		+= sctp/
 obj-$(CONFIG_IEEE80211)		+= ieee80211/
+obj-$(CONFIG_TIPC)		+= tipc/
 
 ifeq ($(CONFIG_NET),y)
 obj-$(CONFIG_SYSCTL)		+= sysctl_net.o
diff --git a/net/tipc/Kconfig b/net/tipc/Kconfig
new file mode 100644
index 00000000000..05ab18e62de
--- /dev/null
+++ b/net/tipc/Kconfig
@@ -0,0 +1,112 @@
+#
+# TIPC configuration
+#
+
+menu "TIPC Configuration (EXPERIMENTAL)"
+	depends on INET && EXPERIMENTAL
+
+config TIPC
+	tristate "The TIPC Protocol (EXPERIMENTAL)"
+	---help---
+	  TBD.
+
+	  This protocol support is also available as a module ( = code which
+	  can be inserted in and removed from the running kernel whenever you
+	  want). The module will be called tipc. If you want to compile it
+	  as a module, say M here and read <file:Documentation/modules.txt>.
+
+	  If in doubt, say N.
+
+config TIPC_ADVANCED
+	bool "TIPC: Advanced configuration"
+	depends on TIPC
+	default n
+	help
+	  Saying Y here will open some advanced configuration
+          for TIPC. Most users do not need to bother, so if
+          unsure, just say N.
+
+config TIPC_ZONES
+	int "Maximum number of zones in network"
+	depends on TIPC && TIPC_ADVANCED
+	default "3"
+	help
+	 Max number of zones inside TIPC network. Max supported value 
+         is 255 zones, minimum is 1
+
+	 Default is 3 zones in a network; setting this to higher
+	 allows more zones but might use more memory.
+
+config TIPC_CLUSTERS
+	int "Maximum number of clusters in a zone"
+	depends on TIPC && TIPC_ADVANCED
+	default "1"
+	help
+          ***Only 1 (one cluster in a zone) is supported by current code.
+          Any value set here will be overridden.***
+
+          (Max number of clusters inside TIPC zone. Max supported 
+          value is 4095 clusters, minimum is 1.
+
+	  Default is 1; setting this to smaller value might save 
+          some memory, setting it to higher
+	  allows more clusters and might consume more memory.)
+
+config TIPC_NODES
+	int "Maximum number of nodes in cluster"
+	depends on TIPC && TIPC_ADVANCED
+	default "255"
+	help
+	  Maximum number of nodes inside a TIPC cluster. Maximum 
+          supported value is 2047 nodes, minimum is 8. 
+
+	  Setting this to a smaller value saves some memory, 
+	  setting it to higher allows more nodes.
+
+config TIPC_SLAVE_NODES
+	int "Maximum number of slave nodes in cluster"
+	depends on TIPC && TIPC_ADVANCED
+	default "0"
+	help
+          ***This capability is not supported by current code.***
+	  
+	  Maximum number of slave nodes inside a TIPC cluster. Maximum 
+          supported value is 2047 nodes, minimum is 0. 
+
+	  Setting this to a smaller value saves some memory, 
+	  setting it to higher allows more nodes.
+
+config TIPC_PORTS
+	int "Maximum number of ports in a node"
+	depends on TIPC && TIPC_ADVANCED
+	default "8191"
+	help
+	  Maximum number of ports within a node. Maximum 
+          supported value is 64535 nodes, minimum is 127. 
+
+	  Setting this to a smaller value saves some memory, 
+	  setting it to higher allows more ports.
+
+config TIPC_LOG
+	int "Size of log buffer"
+	depends on TIPC && TIPC_ADVANCED
+	default 0
+	help
+ 	  Size (in bytes) of TIPC's internal log buffer, which records the
+	  occurrence of significant events.  Maximum supported value
+	  is 32768 bytes, minimum is 0.
+
+	  There is no need to enable the log buffer unless the node will be
+	  managed remotely via TIPC.
+
+config TIPC_DEBUG
+	bool "Enable debugging support"
+	depends on TIPC
+	default n
+	help
+ 	  This will enable debugging of TIPC.
+
+	  Only say Y here if you are having trouble with TIPC.  It will
+	  enable the display of detailed information about what is going on.
+
+endmenu
diff --git a/net/tipc/Makefile b/net/tipc/Makefile
new file mode 100644
index 00000000000..dceb7027946
--- /dev/null
+++ b/net/tipc/Makefile
@@ -0,0 +1,13 @@
+#
+# Makefile for the Linux TIPC layer
+#
+
+obj-$(CONFIG_TIPC) := tipc.o
+
+tipc-y	+= addr.o bcast.o bearer.o config.o cluster.o \
+	   core.o handler.o link.o discover.o msg.o  \
+	   name_distr.o  subscr.o name_table.o net.o  \
+	   netlink.o node.o node_subscr.o port.o ref.o  \
+	   socket.o user_reg.o zone.o dbg.o eth_media.o
+
+# End of file
diff --git a/net/tipc/addr.c b/net/tipc/addr.c
new file mode 100644
index 00000000000..bc353639562
--- /dev/null
+++ b/net/tipc/addr.c
@@ -0,0 +1,91 @@
+/*
+ * net/tipc/addr.c: TIPC address utility routines
+ *     
+ * Copyright (c) 2003-2005, Ericsson Research Canada
+ * Copyright (c) 2004-2005, Wind River Systems
+ * Copyright (c) 2005-2006, Ericsson AB
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without 
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this 
+ * list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright notice, 
+ * this list of conditions and the following disclaimer in the documentation 
+ * and/or other materials provided with the distribution.
+ * Neither the names of the copyright holders nor the names of its 
+ * contributors may be used to endorse or promote products derived from this 
+ * software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "core.h"
+#include "dbg.h"
+#include "addr.h"
+#include "zone.h"
+#include "cluster.h"
+#include "net.h"
+
+u32 tipc_get_addr(void)
+{
+	return tipc_own_addr;
+}
+
+/**
+ * addr_domain_valid - validates a network domain address
+ * 
+ * Accepts <Z.C.N>, <Z.C.0>, <Z.0.0>, and <0.0.0>, 
+ * where Z, C, and N are non-zero and do not exceed the configured limits.
+ * 
+ * Returns 1 if domain address is valid, otherwise 0
+ */
+
+int addr_domain_valid(u32 addr)
+{
+	u32 n = tipc_node(addr);
+	u32 c = tipc_cluster(addr);
+	u32 z = tipc_zone(addr);
+	u32 max_nodes = tipc_max_nodes;
+
+	if (is_slave(addr))
+		max_nodes = LOWEST_SLAVE + tipc_max_slaves;
+	if (n > max_nodes)
+		return 0;
+	if (c > tipc_max_clusters)
+		return 0;
+	if (z > tipc_max_zones)
+		return 0;
+
+	if (n && (!z || !c))
+		return 0;
+	if (c && !z)
+		return 0;
+	return 1;
+}
+
+/**
+ * addr_node_valid - validates a proposed network address for this node
+ * 
+ * Accepts <Z.C.N>, where Z, C, and N are non-zero and do not exceed 
+ * the configured limits.
+ * 
+ * Returns 1 if address can be used, otherwise 0
+ */
+
+int addr_node_valid(u32 addr)
+{
+	return (addr_domain_valid(addr) && tipc_node(addr));
+}
+
diff --git a/net/tipc/addr.h b/net/tipc/addr.h
new file mode 100644
index 00000000000..9dabebcba6d
--- /dev/null
+++ b/net/tipc/addr.h
@@ -0,0 +1,125 @@
+/*
+ * net/tipc/addr.h: Include file for TIPC address utility routines
+ * 
+ * Copyright (c) 2003-2005, Ericsson Research Canada
+ * Copyright (c) 2004-2005, Wind River Systems
+ * Copyright (c) 2005-2006, Ericsson AB
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without 
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this 
+ * list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright notice, 
+ * this list of conditions and the following disclaimer in the documentation 
+ * and/or other materials provided with the distribution.
+ * Neither the names of the copyright holders nor the names of its 
+ * contributors may be used to endorse or promote products derived from this 
+ * software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _TIPC_ADDR_H
+#define _TIPC_ADDR_H
+
+static inline u32 own_node(void)
+{
+	return tipc_node(tipc_own_addr);
+}
+
+static inline u32 own_cluster(void)
+{
+	return tipc_cluster(tipc_own_addr);
+}
+
+static inline u32 own_zone(void)
+{
+	return tipc_zone(tipc_own_addr);
+}
+
+static inline int in_own_cluster(u32 addr)
+{
+	return !((addr ^ tipc_own_addr) >> 12);
+}
+
+static inline int in_own_zone(u32 addr)
+{
+	return !((addr ^ tipc_own_addr) >> 24);
+}
+
+static inline int is_slave(u32 addr)
+{
+	return addr & 0x800;
+}
+
+static inline int may_route(u32 addr)
+{
+	return(addr ^ tipc_own_addr) >> 11;
+}
+
+static inline int in_scope(u32 domain, u32 addr)
+{
+	if (!domain || (domain == addr))
+		return 1;
+	if (domain == (addr & 0xfffff000u)) /* domain <Z.C.0> */
+		return 1;
+	if (domain == (addr & 0xff000000u)) /* domain <Z.0.0> */
+		return 1;
+	return 0;
+}
+
+/**
+ * addr_scope - convert message lookup domain to equivalent 2-bit scope value
+ */
+
+static inline int addr_scope(u32 domain)
+{
+	if (likely(!domain))
+		return TIPC_ZONE_SCOPE;
+	if (tipc_node(domain))
+		return TIPC_NODE_SCOPE;
+	if (tipc_cluster(domain))
+		return TIPC_CLUSTER_SCOPE;
+	return TIPC_ZONE_SCOPE;
+}
+
+/**
+ * addr_domain - convert 2-bit scope value to equivalent message lookup domain
+ *  
+ * Needed when address of a named message must be looked up a second time 
+ * after a network hop.
+ */
+
+static inline int addr_domain(int sc)
+{
+	if (likely(sc == TIPC_NODE_SCOPE))
+		return tipc_own_addr;
+	if (sc == TIPC_CLUSTER_SCOPE)
+		return tipc_addr(tipc_zone(tipc_own_addr),
+				 tipc_cluster(tipc_own_addr), 0);
+	return tipc_addr(tipc_zone(tipc_own_addr), 0, 0);
+}
+
+static inline char *addr_string_fill(char *string, u32 addr)
+{
+	snprintf(string, 16, "<%u.%u.%u>",
+		 tipc_zone(addr), tipc_cluster(addr), tipc_node(addr));
+	return string;
+}
+
+int addr_domain_valid(u32);
+int addr_node_valid(u32 addr);
+
+#endif
diff --git a/net/tipc/bcast.c b/net/tipc/bcast.c
new file mode 100644
index 00000000000..35ca90667a5
--- /dev/null
+++ b/net/tipc/bcast.c
@@ -0,0 +1,803 @@
+/*
+ * net/tipc/bcast.c: TIPC broadcast code
+ *     
+ * Copyright (c) 2003-2005, Ericsson Research Canada
+ * Copyright (c) 2004, Intel Corporation.
+ * Copyright (c) 2005, Wind River Systems
+ * Copyright (c) 2005-2006, Ericsson AB
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without 
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this 
+ * list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright notice, 
+ * this list of conditions and the following disclaimer in the documentation 
+ * and/or other materials provided with the distribution.
+ * Neither the names of the copyright holders nor the names of its 
+ * contributors may be used to endorse or promote products derived from this 
+ * software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "core.h"
+#include "msg.h"
+#include "dbg.h"
+#include "link.h"
+#include "net.h"
+#include "node.h"
+#include "port.h"
+#include "addr.h"
+#include "node_subscr.h"
+#include "name_distr.h"
+#include "bearer.h"
+#include "name_table.h"
+#include "bcast.h"
+
+
+#define MAX_PKT_DEFAULT_MCAST 1500	/* bcast link max packet size (fixed) */
+
+#define BCLINK_WIN_DEFAULT 20		/* bcast link window size (default) */
+
+#define BCLINK_LOG_BUF_SIZE 0
+
+/**
+ * struct bcbearer_pair - a pair of bearers used by broadcast link
+ * @primary: pointer to primary bearer
+ * @secondary: pointer to secondary bearer
+ * 
+ * Bearers must have same priority and same set of reachable destinations 
+ * to be paired.
+ */
+
+struct bcbearer_pair {
+	struct bearer *primary;
+	struct bearer *secondary;
+};
+
+/**
+ * struct bcbearer - bearer used by broadcast link
+ * @bearer: (non-standard) broadcast bearer structure
+ * @media: (non-standard) broadcast media structure
+ * @bpairs: array of bearer pairs
+ * @bpairs_temp: array of bearer pairs used during creation of "bpairs"
+ */
+
+struct bcbearer {
+	struct bearer bearer;
+	struct media media;
+	struct bcbearer_pair bpairs[MAX_BEARERS];
+	struct bcbearer_pair bpairs_temp[TIPC_NUM_LINK_PRI];
+};
+
+/**
+ * struct bclink - link used for broadcast messages
+ * @link: (non-standard) broadcast link structure
+ * @node: (non-standard) node structure representing b'cast link's peer node
+ * 
+ * Handles sequence numbering, fragmentation, bundling, etc.
+ */
+
+struct bclink {
+	struct link link;
+	struct node node;
+};
+
+
+static struct bcbearer *bcbearer = NULL;
+static struct bclink *bclink = NULL;
+static struct link *bcl = NULL;
+static spinlock_t bc_lock = SPIN_LOCK_UNLOCKED;
+
+char bc_link_name[] = "multicast-link";
+
+
+static inline u32 buf_seqno(struct sk_buff *buf)
+{
+	return msg_seqno(buf_msg(buf));
+} 
+
+static inline u32 bcbuf_acks(struct sk_buff *buf)
+{
+	return (u32)TIPC_SKB_CB(buf)->handle;
+}
+
+static inline void bcbuf_set_acks(struct sk_buff *buf, u32 acks)
+{
+	TIPC_SKB_CB(buf)->handle = (void *)acks;
+}
+
+static inline void bcbuf_decr_acks(struct sk_buff *buf)
+{
+	bcbuf_set_acks(buf, bcbuf_acks(buf) - 1);
+}
+
+
+/** 
+ * bclink_set_gap - set gap according to contents of current deferred pkt queue
+ * 
+ * Called with 'node' locked, bc_lock unlocked
+ */
+
+static inline void bclink_set_gap(struct node *n_ptr)
+{
+	struct sk_buff *buf = n_ptr->bclink.deferred_head;
+
+	n_ptr->bclink.gap_after = n_ptr->bclink.gap_to =
+		mod(n_ptr->bclink.last_in);
+	if (unlikely(buf != NULL))
+		n_ptr->bclink.gap_to = mod(buf_seqno(buf) - 1);
+}
+
+/** 
+ * bclink_ack_allowed - test if ACK or NACK message can be sent at this moment
+ * 
+ * This mechanism endeavours to prevent all nodes in network from trying
+ * to ACK or NACK at the same time.
+ * 
+ * Note: TIPC uses a different trigger to distribute ACKs than it does to
+ *       distribute NACKs, but tries to use the same spacing (divide by 16). 
+ */
+
+static inline int bclink_ack_allowed(u32 n)
+{
+	return((n % TIPC_MIN_LINK_WIN) == tipc_own_tag);
+}
+
+
+/** 
+ * bclink_retransmit_pkt - retransmit broadcast packets
+ * @after: sequence number of last packet to *not* retransmit
+ * @to: sequence number of last packet to retransmit
+ * 
+ * Called with 'node' locked, bc_lock unlocked
+ */
+
+static void bclink_retransmit_pkt(u32 after, u32 to)
+{
+	struct sk_buff *buf;
+
+	spin_lock_bh(&bc_lock);
+	buf = bcl->first_out;
+	while (buf && less_eq(buf_seqno(buf), after)) {
+		buf = buf->next;                
+	}
+	if (buf != NULL)
+		link_retransmit(bcl, buf, mod(to - after));
+	spin_unlock_bh(&bc_lock);              
+}
+
+/** 
+ * bclink_acknowledge - handle acknowledgement of broadcast packets
+ * @n_ptr: node that sent acknowledgement info
+ * @acked: broadcast sequence # that has been acknowledged
+ * 
+ * Node is locked, bc_lock unlocked.
+ */
+
+void bclink_acknowledge(struct node *n_ptr, u32 acked)
+{
+	struct sk_buff *crs;
+	struct sk_buff *next;
+	unsigned int released = 0;
+
+	if (less_eq(acked, n_ptr->bclink.acked))
+		return;
+
+	spin_lock_bh(&bc_lock);
+
+	/* Skip over packets that node has previously acknowledged */
+
+	crs = bcl->first_out;
+	while (crs && less_eq(buf_seqno(crs), n_ptr->bclink.acked)) {
+		crs = crs->next;
+	}
+
+	/* Update packets that node is now acknowledging */
+
+	while (crs && less_eq(buf_seqno(crs), acked)) {
+		next = crs->next;
+		bcbuf_decr_acks(crs);
+		if (bcbuf_acks(crs) == 0) {
+			bcl->first_out = next;
+			bcl->out_queue_size--;
+			buf_discard(crs);
+			released = 1;
+		}
+		crs = next;
+	}
+	n_ptr->bclink.acked = acked;
+
+	/* Try resolving broadcast link congestion, if necessary */
+
+	if (unlikely(bcl->next_out))
+		link_push_queue(bcl);
+	if (unlikely(released && !list_empty(&bcl->waiting_ports)))
+		link_wakeup_ports(bcl, 0);
+	spin_unlock_bh(&bc_lock);
+}
+
+/** 
+ * bclink_send_ack - unicast an ACK msg
+ * 
+ * net_lock and node lock set
+ */
+
+static void bclink_send_ack(struct node *n_ptr)
+{
+	struct link *l_ptr = n_ptr->active_links[n_ptr->addr & 1];
+
+	if (l_ptr != NULL)
+		link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, 0, 0);
+}
+
+/** 
+ * bclink_send_nack- broadcast a NACK msg
+ * 
+ * net_lock and node lock set
+ */
+
+static void bclink_send_nack(struct node *n_ptr)
+{
+	struct sk_buff *buf;
+	struct tipc_msg *msg;
+
+	if (!less(n_ptr->bclink.gap_after, n_ptr->bclink.gap_to))
+		return;
+
+	buf = buf_acquire(INT_H_SIZE);
+	if (buf) {
+		msg = buf_msg(buf);
+		msg_init(msg, BCAST_PROTOCOL, STATE_MSG,
+			 TIPC_OK, INT_H_SIZE, n_ptr->addr);
+		msg_set_mc_netid(msg, tipc_net_id);
+		msg_set_bcast_ack(msg, mod(n_ptr->bclink.last_in)); 
+		msg_set_bcgap_after(msg, n_ptr->bclink.gap_after);
+		msg_set_bcgap_to(msg, n_ptr->bclink.gap_to);
+		msg_set_bcast_tag(msg, tipc_own_tag);
+
+		if (bearer_send(&bcbearer->bearer, buf, 0)) {
+			bcl->stats.sent_nacks++;
+			buf_discard(buf);
+		} else {
+			bearer_schedule(bcl->b_ptr, bcl);
+			bcl->proto_msg_queue = buf;
+			bcl->stats.bearer_congs++;
+		}
+
+		/* 
+		 * Ensure we doesn't send another NACK msg to the node
+		 * until 16 more deferred messages arrive from it
+		 * (i.e. helps prevent all nodes from NACK'ing at same time)
+		 */
+		
+		n_ptr->bclink.nack_sync = tipc_own_tag;
+	}
+}
+
+/** 
+ * bclink_check_gap - send a NACK if a sequence gap exists
+ *
+ * net_lock and node lock set
+ */
+
+void bclink_check_gap(struct node *n_ptr, u32 last_sent)
+{
+	if (!n_ptr->bclink.supported ||
+	    less_eq(last_sent, mod(n_ptr->bclink.last_in)))
+		return;
+
+	bclink_set_gap(n_ptr);
+	if (n_ptr->bclink.gap_after == n_ptr->bclink.gap_to)
+		n_ptr->bclink.gap_to = last_sent;
+	bclink_send_nack(n_ptr);
+}
+
+/** 
+ * bclink_peek_nack - process a NACK msg meant for another node
+ * 
+ * Only net_lock set.
+ */
+
+void bclink_peek_nack(u32 dest, u32 sender_tag, u32 gap_after, u32 gap_to)
+{
+	struct node *n_ptr = node_find(dest);
+	u32 my_after, my_to;
+
+	if (unlikely(!n_ptr || !node_is_up(n_ptr)))
+		return;
+	node_lock(n_ptr);
+	/*
+	 * Modify gap to suppress unnecessary NACKs from this node
+	 */
+	my_after = n_ptr->bclink.gap_after;
+	my_to = n_ptr->bclink.gap_to;
+
+	if (less_eq(gap_after, my_after)) {
+		if (less(my_after, gap_to) && less(gap_to, my_to))
+			n_ptr->bclink.gap_after = gap_to;
+		else if (less_eq(my_to, gap_to))
+			n_ptr->bclink.gap_to = n_ptr->bclink.gap_after;
+	} else if (less_eq(gap_after, my_to)) {
+		if (less_eq(my_to, gap_to))
+			n_ptr->bclink.gap_to = gap_after;
+	} else {
+		/* 
+		 * Expand gap if missing bufs not in deferred queue:
+		 */
+		struct sk_buff *buf = n_ptr->bclink.deferred_head;
+		u32 prev = n_ptr->bclink.gap_to;
+
+		for (; buf; buf = buf->next) {
+			u32 seqno = buf_seqno(buf);
+
+			if (mod(seqno - prev) != 1)
+				buf = NULL;
+			if (seqno == gap_after)
+				break;
+			prev = seqno;
+		}
+		if (buf == NULL)
+			n_ptr->bclink.gap_to = gap_after;
+	}
+	/*
+	 * Some nodes may send a complementary NACK now:
+	 */ 
+	if (bclink_ack_allowed(sender_tag + 1)) {
+		if (n_ptr->bclink.gap_to != n_ptr->bclink.gap_after) {
+			bclink_send_nack(n_ptr);
+			bclink_set_gap(n_ptr);
+		}
+	}
+	node_unlock(n_ptr);
+}
+
+/**
+ * bclink_send_msg - broadcast a packet to all nodes in cluster
+ */
+
+int bclink_send_msg(struct sk_buff *buf)
+{
+	int res;
+
+	spin_lock_bh(&bc_lock);
+
+	res = link_sen