net/tipc/cluster.c - kernel/prism - Git at Google

 /*
  * net/tipc/cluster.c: TIPC cluster management routines
  *
  * Copyright (c) 2000-2006, Ericsson AB
  * Copyright (c) 2005, Wind River Systems
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. 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.
  * 3. 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.
  *
  * Alternatively, this software may be distributed under the terms of the
  * GNU General Public License ("GPL") version 2 as published by the Free
  * Software Foundation.
  *
  * 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 "cluster.h"
 #include "addr.h"
 #include "node_subscr.h"
 #include "link.h"
 #include "node.h"
 #include "net.h"
 #include "msg.h"
 #include "bearer.h"

 static void tipc_cltr_multicast(struct cluster *c_ptr, struct sk_buff *buf,
 				u32 lower, u32 upper);
 static struct sk_buff *tipc_cltr_prepare_routing_msg(u32 data_size, u32 dest);

 struct tipc_node **tipc_local_nodes = NULL;
 struct tipc_node_map tipc_cltr_bcast_nodes = {0,{0,}};
 u32 tipc_highest_allowed_slave = 0;

 struct cluster *tipc_cltr_create(u32 addr)
 {
 	struct _zone *z_ptr;
 	struct cluster *c_ptr;
 	int max_nodes;

 	c_ptr = kzalloc(sizeof(*c_ptr), GFP_ATOMIC);
 	if (c_ptr == NULL) {
 		warn("Cluster creation failure, no memory\n");
 		return NULL;
 	}

 	c_ptr->addr = tipc_addr(tipc_zone(addr), tipc_cluster(addr), 0);
 	if (in_own_cluster(addr))
 		max_nodes = LOWEST_SLAVE + tipc_max_slaves;
 	else
 		max_nodes = tipc_max_nodes + 1;

 	c_ptr->nodes = kcalloc(max_nodes + 1, sizeof(void*), GFP_ATOMIC);
 	if (c_ptr->nodes == NULL) {
 		warn("Cluster creation failure, no memory for node area\n");
 		kfree(c_ptr);
 		return NULL;
 	}

 	if (in_own_cluster(addr))
 		tipc_local_nodes = c_ptr->nodes;
 	c_ptr->highest_slave = LOWEST_SLAVE - 1;
 	c_ptr->highest_node = 0;

 	z_ptr = tipc_zone_find(tipc_zone(addr));
 	if (!z_ptr) {
 		z_ptr = tipc_zone_create(addr);
 	}
 	if (!z_ptr) {
 		kfree(c_ptr->nodes);
 		kfree(c_ptr);
 		return NULL;
 	}

 	tipc_zone_attach_cluster(z_ptr, c_ptr);
 	c_ptr->owner = z_ptr;
 	return c_ptr;
 }

 void tipc_cltr_delete(struct cluster *c_ptr)
 {
 	u32 n_num;

 	if (!c_ptr)
 		return;
 	for (n_num = 1; n_num <= c_ptr->highest_node; n_num++) {
 		tipc_node_delete(c_ptr->nodes[n_num]);
 	}
 	for (n_num = LOWEST_SLAVE; n_num <= c_ptr->highest_slave; n_num++) {
 		tipc_node_delete(c_ptr->nodes[n_num]);
 	}
 	kfree(c_ptr->nodes);
 	kfree(c_ptr);
 }

 u32 tipc_cltr_next_node(struct cluster *c_ptr, u32 addr)
 {
 	struct tipc_node *n_ptr;
 	u32 n_num = tipc_node(addr) + 1;

 	if (!c_ptr)
 		return addr;
 	for (; n_num <= c_ptr->highest_node; n_num++) {
 		n_ptr = c_ptr->nodes[n_num];
 		if (n_ptr && tipc_node_has_active_links(n_ptr))
 			return n_ptr->addr;
 	}
 	for (n_num = 1; n_num < tipc_node(addr); n_num++) {
 		n_ptr = c_ptr->nodes[n_num];
 		if (n_ptr && tipc_node_has_active_links(n_ptr))
 			return n_ptr->addr;
 	}
 	return 0;
 }

 void tipc_cltr_attach_node(struct cluster *c_ptr, struct tipc_node *n_ptr)
 {
 	u32 n_num = tipc_node(n_ptr->addr);
 	u32 max_n_num = tipc_max_nodes;

 	if (in_own_cluster(n_ptr->addr))
 		max_n_num = tipc_highest_allowed_slave;
 	assert(n_num > 0);
 	assert(n_num <= max_n_num);
 	assert(c_ptr->nodes[n_num] == NULL);
 	c_ptr->nodes[n_num] = n_ptr;
 	if (n_num > c_ptr->highest_node)
 		c_ptr->highest_node = n_num;
 }

 /**
  * tipc_cltr_select_router - select router to a cluster
  *
  * Uses deterministic and fair algorithm.
  */

 u32 tipc_cltr_select_router(struct cluster *c_ptr, u32 ref)
 {
 	u32 n_num;
 	u32 ulim = c_ptr->highest_node;
 	u32 mask;
 	u32 tstart;

 	assert(!in_own_cluster(c_ptr->addr));
 	if (!ulim)
 		return 0;

 	/* Start entry must be random */
 	mask = tipc_max_nodes;
 	while (mask > ulim)
 		mask >>= 1;
 	tstart = ref & mask;
 	n_num = tstart;

 	/* Lookup upwards with wrap-around */
 	do {
 		if (tipc_node_is_up(c_ptr->nodes[n_num]))
 			break;
 	} while (++n_num <= ulim);
 	if (n_num > ulim) {
 		n_num = 1;
 		do {
 			if (tipc_node_is_up(c_ptr->nodes[n_num]))
 				break;
 		} while (++n_num < tstart);
 		if (n_num == tstart)
 			return 0;
 	}
 	assert(n_num <= ulim);
 	return tipc_node_select_router(c_ptr->nodes[n_num], ref);
 }

 /**
  * tipc_cltr_select_node - select destination node within a remote cluster
  *
  * Uses deterministic and fair algorithm.
  */

 struct tipc_node *tipc_cltr_select_node(struct cluster *c_ptr, u32 selector)
 {
 	u32 n_num;
 	u32 mask = tipc_max_nodes;
 	u32 start_entry;

 	assert(!in_own_cluster(c_ptr->addr));
 	if (!c_ptr->highest_node)
 		return NULL;

 	/* Start entry must be random */
 	while (mask > c_ptr->highest_node) {
 		mask >>= 1;
 	}
 	start_entry = (selector & mask) ? selector & mask : 1u;
 	assert(start_entry <= c_ptr->highest_node);

 	/* Lookup upwards with wrap-around */
 	for (n_num = start_entry; n_num <= c_ptr->highest_node; n_num++) {
 		if (tipc_node_has_active_links(c_ptr->nodes[n_num]))
 			return c_ptr->nodes[n_num];
 	}
 	for (n_num = 1; n_num < start_entry; n_num++) {
 		if (tipc_node_has_active_links(c_ptr->nodes[n_num]))
 			return c_ptr->nodes[n_num];
 	}
 	return NULL;
 }

 /*
  *    Routing table management: See description in node.c
  */

 static struct sk_buff *tipc_cltr_prepare_routing_msg(u32 data_size, u32 dest)
 {
 	u32 size = INT_H_SIZE + data_size;
 	struct sk_buff *buf = buf_acquire(size);
 	struct tipc_msg *msg;

 	if (buf) {
 		msg = buf_msg(buf);
 		memset((char *)msg, 0, size);
 		msg_init(msg, ROUTE_DISTRIBUTOR, 0, INT_H_SIZE, dest);
 	}
 	return buf;
 }

 void tipc_cltr_bcast_new_route(struct cluster *c_ptr, u32 dest,
 			     u32 lower, u32 upper)
 {
 	struct sk_buff *buf = tipc_cltr_prepare_routing_msg(0, c_ptr->addr);
 	struct tipc_msg *msg;

 	if (buf) {
 		msg = buf_msg(buf);
 		msg_set_remote_node(msg, dest);
 		msg_set_type(msg, ROUTE_ADDITION);
 		tipc_cltr_multicast(c_ptr, buf, lower, upper);
 	} else {
 		warn("Memory squeeze: broadcast of new route failed\n");
 	}
 }

 void tipc_cltr_bcast_lost_route(struct cluster *c_ptr, u32 dest,
 				u32 lower, u32 upper)
 {
 	struct sk_buff *buf = tipc_cltr_prepare_routing_msg(0, c_ptr->addr);
 	struct tipc_msg *msg;

 	if (buf) {
 		msg = buf_msg(buf);
 		msg_set_remote_node(msg, dest);
 		msg_set_type(msg, ROUTE_REMOVAL);
 		tipc_cltr_multicast(c_ptr, buf, lower, upper);
 	} else {
 		warn("Memory squeeze: broadcast of lost route failed\n");
 	}
 }

 void tipc_cltr_send_slave_routes(struct cluster *c_ptr, u32 dest)
 {
 	struct sk_buff *buf;
 	struct tipc_msg *msg;
 	u32 highest = c_ptr->highest_slave;
 	u32 n_num;
 	int send = 0;

 	assert(!is_slave(dest));
 	assert(in_own_cluster(dest));
 	assert(in_own_cluster(c_ptr->addr));
 	if (highest <= LOWEST_SLAVE)
 		return;
 	buf = tipc_cltr_prepare_routing_msg(highest - LOWEST_SLAVE + 1,
 					    c_ptr->addr);
 	if (buf) {
 		msg = buf_msg(buf);
 		msg_set_remote_node(msg, c_ptr->addr);
 		msg_set_type(msg, SLAVE_ROUTING_TABLE);
 		for (n_num = LOWEST_SLAVE; n_num <= highest; n_num++) {
 			if (c_ptr->nodes[n_num] &&
 			    tipc_node_has_active_links(c_ptr->nodes[n_num])) {
 				send = 1;
 				msg_set_dataoctet(msg, n_num);
 			}
 		}
 		if (send)
 			tipc_link_send(buf, dest, dest);
 		else
 			buf_discard(buf);
 	} else {
 		warn("Memory squeeze: broadcast of lost route failed\n");
 	}
 }

 void tipc_cltr_send_ext_routes(struct cluster *c_ptr, u32 dest)
 {
 	struct sk_buff *buf;
 	struct tipc_msg *msg;
 	u32 highest = c_ptr->highest_node;
 	u32 n_num;
 	int send = 0;

 	if (in_own_cluster(c_ptr->addr))
 		return;
 	assert(!is_slave(dest));
 	assert(in_own_cluster(dest));
 	highest = c_ptr->highest_node;
 	buf = tipc_cltr_prepare_routing_msg(highest + 1, c_ptr->addr);
 	if (buf) {
 		msg = buf_msg(buf);
 		msg_set_remote_node(msg, c_ptr->addr);
 		msg_set_type(msg, EXT_ROUTING_TABLE);
 		for (n_num = 1; n_num <= highest; n_num++) {
 			if (c_ptr->nodes[n_num] &&
 			    tipc_node_has_active_links(c_ptr->nodes[n_num])) {
 				send = 1;
 				msg_set_dataoctet(msg, n_num);
 			}
 		}
 		if (send)
 			tipc_link_send(buf, dest, dest);
 		else
 			buf_discard(buf);
 	} else {
 		warn("Memory squeeze: broadcast of external route failed\n");
 	}
 }

 void tipc_cltr_send_local_routes(struct cluster *c_ptr, u32 dest)
 {
 	struct sk_buff *buf;
 	struct tipc_msg *msg;
 	u32 highest = c_ptr->highest_node;
 	u32 n_num;
 	int send = 0;

 	assert(is_slave(dest));
 	assert(in_own_cluster(c_ptr->addr));
 	buf = tipc_cltr_prepare_routing_msg(highest, c_ptr->addr);
 	if (buf) {
 		msg = buf_msg(buf);
 		msg_set_remote_node(msg, c_ptr->addr);
 		msg_set_type(msg, LOCAL_ROUTING_TABLE);
 		for (n_num = 1; n_num <= highest; n_num++) {
 			if (c_ptr->nodes[n_num] &&
 			    tipc_node_has_active_links(c_ptr->nodes[n_num])) {
 				send = 1;
 				msg_set_dataoctet(msg, n_num);
 			}
 		}
 		if (send)
 			tipc_link_send(buf, dest, dest);
 		else
 			buf_discard(buf);
 	} else {
 		warn("Memory squeeze: broadcast of local route failed\n");
 	}
 }

 void tipc_cltr_recv_routing_table(struct sk_buff *buf)
 {
 	struct tipc_msg *msg = buf_msg(buf);
 	struct cluster *c_ptr;
 	struct tipc_node *n_ptr;
 	unchar *node_table;
 	u32 table_size;
 	u32 router;
 	u32 rem_node = msg_remote_node(msg);
 	u32 z_num;
 	u32 c_num;
 	u32 n_num;

 	c_ptr = tipc_cltr_find(rem_node);
 	if (!c_ptr) {
 		c_ptr = tipc_cltr_create(rem_node);
 		if (!c_ptr) {
 			buf_discard(buf);
 			return;
 		}
 	}

 	node_table = buf->data + msg_hdr_sz(msg);
 	table_size = msg_size(msg) - msg_hdr_sz(msg);
 	router = msg_prevnode(msg);
 	z_num = tipc_zone(rem_node);
 	c_num = tipc_cluster(rem_node);

 	switch (msg_type(msg)) {
 	case LOCAL_ROUTING_TABLE:
 		assert(is_slave(tipc_own_addr));
 	case EXT_ROUTING_TABLE:
 		for (n_num = 1; n_num < table_size; n_num++) {
 			if (node_table[n_num]) {
 				u32 addr = tipc_addr(z_num, c_num, n_num);
 				n_ptr = c_ptr->nodes[n_num];
 				if (!n_ptr) {
 					n_ptr = tipc_node_create(addr);
 				}
 				if (n_ptr)
 					tipc_node_add_router(n_ptr, router);
 			}
 		}
 		break;
 	case SLAVE_ROUTING_TABLE:
 		assert(!is_slave(tipc_own_addr));
 		assert(in_own_cluster(c_ptr->addr));
 		for (n_num = 1; n_num < table_size; n_num++) {
 			if (node_table[n_num]) {
 				u32 slave_num = n_num + LOWEST_SLAVE;
 				u32 addr = tipc_addr(z_num, c_num, slave_num);
 				n_ptr = c_ptr->nodes[slave_num];
 				if (!n_ptr) {
 					n_ptr = tipc_node_create(addr);
 				}
 				if (n_ptr)
 					tipc_node_add_router(n_ptr, router);
 			}
 		}
 		break;
 	case ROUTE_ADDITION:
 		if (!is_slave(tipc_own_addr)) {
 			assert(!in_own_cluster(c_ptr->addr)
 			       || is_slave(rem_node));
 		} else {
 			assert(in_own_cluster(c_ptr->addr)
 			       && !is_slave(rem_node));
 		}
 		n_ptr = c_ptr->nodes[tipc_node(rem_node)];
 		if (!n_ptr)
 			n_ptr = tipc_node_create(rem_node);
 		if (n_ptr)
 			tipc_node_add_router(n_ptr, router);
 		break;
 	case ROUTE_REMOVAL:
 		if (!is_slave(tipc_own_addr)) {
 			assert(!in_own_cluster(c_ptr->addr)
 			       || is_slave(rem_node));
 		} else {
 			assert(in_own_cluster(c_ptr->addr)
 			       && !is_slave(rem_node));
 		}
 		n_ptr = c_ptr->nodes[tipc_node(rem_node)];
 		if (n_ptr)
 			tipc_node_remove_router(n_ptr, router);
 		break;
 	default:
 		assert(!"Illegal routing manager message received\n");
 	}
 	buf_discard(buf);
 }

 void tipc_cltr_remove_as_router(struct cluster *c_ptr, u32 router)
 {
 	u32 start_entry;
 	u32 tstop;
 	u32 n_num;

 	if (is_slave(router))
 		return;	/* Slave nodes can not be routers */

 	if (in_own_cluster(c_ptr->addr)) {
 		start_entry = LOWEST_SLAVE;
 		tstop = c_ptr->highest_slave;
 	} else {
 		start_entry = 1;
 		tstop = c_ptr->highest_node;
 	}

 	for (n_num = start_entry; n_num <= tstop; n_num++) {
 		if (c_ptr->nodes[n_num]) {
 			tipc_node_remove_router(c_ptr->nodes[n_num], router);
 		}
 	}
 }

 /**
  * tipc_cltr_multicast - multicast message to local nodes
  */

 static void tipc_cltr_multicast(struct cluster *c_ptr, struct sk_buff *buf,
 			 u32 lower, u32 upper)
 {
 	struct sk_buff *buf_copy;
 	struct tipc_node *n_ptr;
 	u32 n_num;
 	u32 tstop;

 	assert(lower <= upper);
 	assert(((lower >= 1) && (lower <= tipc_max_nodes)) ||
 	       ((lower >= LOWEST_SLAVE) && (lower <= tipc_highest_allowed_slave)));
 	assert(((upper >= 1) && (upper <= tipc_max_nodes)) ||
 	       ((upper >= LOWEST_SLAVE) && (upper <= tipc_highest_allowed_slave)));
 	assert(in_own_cluster(c_ptr->addr));

 	tstop = is_slave(upper) ? c_ptr->highest_slave : c_ptr->highest_node;
 	if (tstop > upper)
 		tstop = upper;
 	for (n_num = lower; n_num <= tstop; n_num++) {
 		n_ptr = c_ptr->nodes[n_num];
 		if (n_ptr && tipc_node_has_active_links(n_ptr)) {
 			buf_copy = skb_copy(buf, GFP_ATOMIC);
 			if (buf_copy == NULL)
 				break;
 			msg_set_destnode(buf_msg(buf_copy), n_ptr->addr);
 			tipc_link_send(buf_copy, n_ptr->addr, n_ptr->addr);
 		}
 	}
 	buf_discard(buf);
 }

 /**
  * tipc_cltr_broadcast - broadcast message to all nodes within cluster
  */

 void tipc_cltr_broadcast(struct sk_buff *buf)
 {
 	struct sk_buff *buf_copy;
 	struct cluster *c_ptr;
 	struct tipc_node *n_ptr;
 	u32 n_num;
 	u32 tstart;
 	u32 tstop;
 	u32 node_type;

 	if (tipc_mode == TIPC_NET_MODE) {
 		c_ptr = tipc_cltr_find(tipc_own_addr);
 		assert(in_own_cluster(c_ptr->addr));	/* For now */

 		/* Send to standard nodes, then repeat loop sending to slaves */
 		tstart = 1;
 		tstop = c_ptr->highest_node;
 		for (node_type = 1; node_type <= 2; node_type++) {
 			for (n_num = tstart; n_num <= tstop; n_num++) {
 				n_ptr = c_ptr->nodes[n_num];
 				if (n_ptr && tipc_node_has_active_links(n_ptr)) {
 					buf_copy = skb_copy(buf, GFP_ATOMIC);
 					if (buf_copy == NULL)
 						goto exit;
 					msg_set_destnode(buf_msg(buf_copy),
 							 n_ptr->addr);
 					tipc_link_send(buf_copy, n_ptr->addr,
 						       n_ptr->addr);
 				}
 			}
 			tstart = LOWEST_SLAVE;
 			tstop = c_ptr->highest_slave;
 		}
 	}
 exit:
 	buf_discard(buf);
 }

 int tipc_cltr_init(void)
 {
 	tipc_highest_allowed_slave = LOWEST_SLAVE + tipc_max_slaves;
 	return tipc_cltr_create(tipc_own_addr) ? 0 : -ENOMEM;
 }
	/*
	* net/tipc/cluster.c: TIPC cluster management routines
	*
	* Copyright (c) 2000-2006, Ericsson AB
	* Copyright (c) 2005, Wind River Systems
	* All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions are met:
	*
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* 2. 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.
	* 3. 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.
	*
	* Alternatively, this software may be distributed under the terms of the
	* GNU General Public License ("GPL") version 2 as published by the Free
	* Software Foundation.
	*
	* 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 "cluster.h"
	#include "addr.h"
	#include "node_subscr.h"
	#include "link.h"
	#include "node.h"
	#include "net.h"
	#include "msg.h"
	#include "bearer.h"

	static void tipc_cltr_multicast(struct cluster c_ptr, struct sk_buff buf,
	u32 lower, u32 upper);
	static struct sk_buff *tipc_cltr_prepare_routing_msg(u32 data_size, u32 dest);

	struct tipc_node **tipc_local_nodes = NULL;
	struct tipc_node_map tipc_cltr_bcast_nodes = {0,{0,}};
	u32 tipc_highest_allowed_slave = 0;

	struct cluster *tipc_cltr_create(u32 addr)
	{
	struct _zone *z_ptr;
	struct cluster *c_ptr;
	int max_nodes;

	c_ptr = kzalloc(sizeof(*c_ptr), GFP_ATOMIC);
	if (c_ptr == NULL) {
	warn("Cluster creation failure, no memory\n");
	return NULL;
	}

	c_ptr->addr = tipc_addr(tipc_zone(addr), tipc_cluster(addr), 0);
	if (in_own_cluster(addr))
	max_nodes = LOWEST_SLAVE + tipc_max_slaves;
	else
	max_nodes = tipc_max_nodes + 1;

	c_ptr->nodes = kcalloc(max_nodes + 1, sizeof(void*), GFP_ATOMIC);
	if (c_ptr->nodes == NULL) {
	warn("Cluster creation failure, no memory for node area\n");
	kfree(c_ptr);
	return NULL;
	}

	if (in_own_cluster(addr))
	tipc_local_nodes = c_ptr->nodes;
	c_ptr->highest_slave = LOWEST_SLAVE - 1;
	c_ptr->highest_node = 0;

	z_ptr = tipc_zone_find(tipc_zone(addr));
	if (!z_ptr) {
	z_ptr = tipc_zone_create(addr);
	}
	if (!z_ptr) {
	kfree(c_ptr->nodes);
	kfree(c_ptr);
	return NULL;
	}

	tipc_zone_attach_cluster(z_ptr, c_ptr);
	c_ptr->owner = z_ptr;
	return c_ptr;
	}

	void tipc_cltr_delete(struct cluster *c_ptr)
	{
	u32 n_num;

	if (!c_ptr)
	return;
	for (n_num = 1; n_num <= c_ptr->highest_node; n_num++) {
	tipc_node_delete(c_ptr->nodes[n_num]);
	}
	for (n_num = LOWEST_SLAVE; n_num <= c_ptr->highest_slave; n_num++) {
	tipc_node_delete(c_ptr->nodes[n_num]);
	}
	kfree(c_ptr->nodes);
	kfree(c_ptr);
	}

	u32 tipc_cltr_next_node(struct cluster *c_ptr, u32 addr)
	{
	struct tipc_node *n_ptr;
	u32 n_num = tipc_node(addr) + 1;

	if (!c_ptr)
	return addr;
	for (; n_num <= c_ptr->highest_node; n_num++) {
	n_ptr = c_ptr->nodes[n_num];
	if (n_ptr && tipc_node_has_active_links(n_ptr))
	return n_ptr->addr;
	}
	for (n_num = 1; n_num < tipc_node(addr); n_num++) {
	n_ptr = c_ptr->nodes[n_num];
	if (n_ptr && tipc_node_has_active_links(n_ptr))
	return n_ptr->addr;
	}
	return 0;
	}

	void tipc_cltr_attach_node(struct cluster c_ptr, struct tipc_node n_ptr)
	{
	u32 n_num = tipc_node(n_ptr->addr);
	u32 max_n_num = tipc_max_nodes;

	if (in_own_cluster(n_ptr->addr))
	max_n_num = tipc_highest_allowed_slave;
	assert(n_num > 0);
	assert(n_num <= max_n_num);
	assert(c_ptr->nodes[n_num] == NULL);
	c_ptr->nodes[n_num] = n_ptr;
	if (n_num > c_ptr->highest_node)
	c_ptr->highest_node = n_num;
	}

	/**
	* tipc_cltr_select_router - select router to a cluster
	*
	* Uses deterministic and fair algorithm.
	*/

	u32 tipc_cltr_select_router(struct cluster *c_ptr, u32 ref)
	{
	u32 n_num;
	u32 ulim = c_ptr->highest_node;
	u32 mask;
	u32 tstart;

	assert(!in_own_cluster(c_ptr->addr));
	if (!ulim)
	return 0;

	/* Start entry must be random */
	mask = tipc_max_nodes;
	while (mask > ulim)
	mask >>= 1;
	tstart = ref & mask;
	n_num = tstart;

	/* Lookup upwards with wrap-around */
	do {
	if (tipc_node_is_up(c_ptr->nodes[n_num]))
	break;
	} while (++n_num <= ulim);
	if (n_num > ulim) {
	n_num = 1;
	do {
	if (tipc_node_is_up(c_ptr->nodes[n_num]))
	break;
	} while (++n_num < tstart);
	if (n_num == tstart)
	return 0;
	}
	assert(n_num <= ulim);
	return tipc_node_select_router(c_ptr->nodes[n_num], ref);
	}

	/**
	* tipc_cltr_select_node - select destination node within a remote cluster
	*
	* Uses deterministic and fair algorithm.
	*/

	struct tipc_node tipc_cltr_select_node(struct cluster c_ptr, u32 selector)
	{
	u32 n_num;
	u32 mask = tipc_max_nodes;
	u32 start_entry;

	assert(!in_own_cluster(c_ptr->addr));
	if (!c_ptr->highest_node)
	return NULL;

	/* Start entry must be random */
	while (mask > c_ptr->highest_node) {
	mask >>= 1;
	}
	start_entry = (selector & mask) ? selector & mask : 1u;
	assert(start_entry <= c_ptr->highest_node);

	/* Lookup upwards with wrap-around */
	for (n_num = start_entry; n_num <= c_ptr->highest_node; n_num++) {
	if (tipc_node_has_active_links(c_ptr->nodes[n_num]))
	return c_ptr->nodes[n_num];
	}
	for (n_num = 1; n_num < start_entry; n_num++) {
	if (tipc_node_has_active_links(c_ptr->nodes[n_num]))
	return c_ptr->nodes[n_num];
	}
	return NULL;
	}

	/*
	* Routing table management: See description in node.c
	*/

	static struct sk_buff *tipc_cltr_prepare_routing_msg(u32 data_size, u32 dest)
	{
	u32 size = INT_H_SIZE + data_size;
	struct sk_buff *buf = buf_acquire(size);
	struct tipc_msg *msg;

	if (buf) {
	msg = buf_msg(buf);
	memset((char *)msg, 0, size);
	msg_init(msg, ROUTE_DISTRIBUTOR, 0, INT_H_SIZE, dest);
	}
	return buf;
	}

	void tipc_cltr_bcast_new_route(struct cluster *c_ptr, u32 dest,
	u32 lower, u32 upper)
	{
	struct sk_buff *buf = tipc_cltr_prepare_routing_msg(0, c_ptr->addr);
	struct tipc_msg *msg;

	if (buf) {
	msg = buf_msg(buf);
	msg_set_remote_node(msg, dest);
	msg_set_type(msg, ROUTE_ADDITION);
	tipc_cltr_multicast(c_ptr, buf, lower, upper);
	} else {
	warn("Memory squeeze: broadcast of new route failed\n");
	}
	}

	void tipc_cltr_bcast_lost_route(struct cluster *c_ptr, u32 dest,
	u32 lower, u32 upper)
	{
	struct sk_buff *buf = tipc_cltr_prepare_routing_msg(0, c_ptr->addr);
	struct tipc_msg *msg;

	if (buf) {
	msg = buf_msg(buf);
	msg_set_remote_node(msg, dest);
	msg_set_type(msg, ROUTE_REMOVAL);
	tipc_cltr_multicast(c_ptr, buf, lower, upper);
	} else {
	warn("Memory squeeze: broadcast of lost route failed\n");
	}
	}

	void tipc_cltr_send_slave_routes(struct cluster *c_ptr, u32 dest)
	{
	struct sk_buff *buf;
	struct tipc_msg *msg;
	u32 highest = c_ptr->highest_slave;
	u32 n_num;
	int send = 0;

	assert(!is_slave(dest));
	assert(in_own_cluster(dest));
	assert(in_own_cluster(c_ptr->addr));
	if (highest <= LOWEST_SLAVE)
	return;
	buf = tipc_cltr_prepare_routing_msg(highest - LOWEST_SLAVE + 1,
	c_ptr->addr);
	if (buf) {
	msg = buf_msg(buf);
	msg_set_remote_node(msg, c_ptr->addr);
	msg_set_type(msg, SLAVE_ROUTING_TABLE);
	for (n_num = LOWEST_SLAVE; n_num <= highest; n_num++) {
	if (c_ptr->nodes[n_num] &&
	tipc_node_has_active_links(c_ptr->nodes[n_num])) {
	send = 1;
	msg_set_dataoctet(msg, n_num);
	}
	}
	if (send)
	tipc_link_send(buf, dest, dest);
	else
	buf_discard(buf);
	} else {
	warn("Memory squeeze: broadcast of lost route failed\n");
	}
	}

	void tipc_cltr_send_ext_routes(struct cluster *c_ptr, u32 dest)
	{
	struct sk_buff *buf;
	struct tipc_msg *msg;
	u32 highest = c_ptr->highest_node;
	u32 n_num;
	int send = 0;

	if (in_own_cluster(c_ptr->addr))
	return;
	assert(!is_slave(dest));
	assert(in_own_cluster(dest));
	highest = c_ptr->highest_node;
	buf = tipc_cltr_prepare_routing_msg(highest + 1, c_ptr->addr);
	if (buf) {
	msg = buf_msg(buf);
	msg_set_remote_node(msg, c_ptr->addr);
	msg_set_type(msg, EXT_ROUTING_TABLE);
	for (n_num = 1; n_num <= highest; n_num++) {
	if (c_ptr->nodes[n_num] &&
	tipc_node_has_active_links(c_ptr->nodes[n_num])) {
	send = 1;
	msg_set_dataoctet(msg, n_num);
	}
	}
	if (send)
	tipc_link_send(buf, dest, dest);
	else
	buf_discard(buf);
	} else {
	warn("Memory squeeze: broadcast of external route failed\n");
	}
	}

	void tipc_cltr_send_local_routes(struct cluster *c_ptr, u32 dest)
	{
	struct sk_buff *buf;
	struct tipc_msg *msg;
	u32 highest = c_ptr->highest_node;
	u32 n_num;
	int send = 0;

	assert(is_slave(dest));
	assert(in_own_cluster(c_ptr->addr));
	buf = tipc_cltr_prepare_routing_msg(highest, c_ptr->addr);
	if (buf) {
	msg = buf_msg(buf);
	msg_set_remote_node(msg, c_ptr->addr);
	msg_set_type(msg, LOCAL_ROUTING_TABLE);
	for (n_num = 1; n_num <= highest; n_num++) {
	if (c_ptr->nodes[n_num] &&
	tipc_node_has_active_links(c_ptr->nodes[n_num])) {
	send = 1;
	msg_set_dataoctet(msg, n_num);
	}
	}
	if (send)
	tipc_link_send(buf, dest, dest);
	else
	buf_discard(buf);
	} else {
	warn("Memory squeeze: broadcast of local route failed\n");
	}
	}

	void tipc_cltr_recv_routing_table(struct sk_buff *buf)
	{
	struct tipc_msg *msg = buf_msg(buf);
	struct cluster *c_ptr;
	struct tipc_node *n_ptr;
	unchar *node_table;
	u32 table_size;
	u32 router;
	u32 rem_node = msg_remote_node(msg);
	u32 z_num;
	u32 c_num;
	u32 n_num;

	c_ptr = tipc_cltr_find(rem_node);
	if (!c_ptr) {
	c_ptr = tipc_cltr_create(rem_node);
	if (!c_ptr) {
	buf_discard(buf);
	return;
	}
	}

	node_table = buf->data + msg_hdr_sz(msg);
	table_size = msg_size(msg) - msg_hdr_sz(msg);
	router = msg_prevnode(msg);
	z_num = tipc_zone(rem_node);
	c_num = tipc_cluster(rem_node);

	switch (msg_type(msg)) {
	case LOCAL_ROUTING_TABLE:
	assert(is_slave(tipc_own_addr));
	case EXT_ROUTING_TABLE:
	for (n_num = 1; n_num < table_size; n_num++) {
	if (node_table[n_num]) {
	u32 addr = tipc_addr(z_num, c_num, n_num);
	n_ptr = c_ptr->nodes[n_num];
	if (!n_ptr) {
	n_ptr = tipc_node_create(addr);
	}
	if (n_ptr)
	tipc_node_add_router(n_ptr, router);
	}
	}
	break;
	case SLAVE_ROUTING_TABLE:
	assert(!is_slave(tipc_own_addr));
	assert(in_own_cluster(c_ptr->addr));
	for (n_num = 1; n_num < table_size; n_num++) {
	if (node_table[n_num]) {
	u32 slave_num = n_num + LOWEST_SLAVE;
	u32 addr = tipc_addr(z_num, c_num, slave_num);
	n_ptr = c_ptr->nodes[slave_num];
	if (!n_ptr) {
	n_ptr = tipc_node_create(addr);
	}
	if (n_ptr)
	tipc_node_add_router(n_ptr, router);
	}
	}
	break;
	case ROUTE_ADDITION:
	if (!is_slave(tipc_own_addr)) {
	assert(!in_own_cluster(c_ptr->addr)
	\|\| is_slave(rem_node));
	} else {
	assert(in_own_cluster(c_ptr->addr)
	&& !is_slave(rem_node));
	}
	n_ptr = c_ptr->nodes[tipc_node(rem_node)];
	if (!n_ptr)
	n_ptr = tipc_node_create(rem_node);
	if (n_ptr)
	tipc_node_add_router(n_ptr, router);
	break;
	case ROUTE_REMOVAL:
	if (!is_slave(tipc_own_addr)) {
	assert(!in_own_cluster(c_ptr->addr)
	\|\| is_slave(rem_node));
	} else {
	assert(in_own_cluster(c_ptr->addr)
	&& !is_slave(rem_node));
	}
	n_ptr = c_ptr->nodes[tipc_node(rem_node)];
	if (n_ptr)
	tipc_node_remove_router(n_ptr, router);
	break;
	default:
	assert(!"Illegal routing manager message received\n");
	}
	buf_discard(buf);
	}

	void tipc_cltr_remove_as_router(struct cluster *c_ptr, u32 router)
	{
	u32 start_entry;
	u32 tstop;
	u32 n_num;

	if (is_slave(router))
	return; /* Slave nodes can not be routers */

	if (in_own_cluster(c_ptr->addr)) {
	start_entry = LOWEST_SLAVE;
	tstop = c_ptr->highest_slave;
	} else {
	start_entry = 1;
	tstop = c_ptr->highest_node;
	}

	for (n_num = start_entry; n_num <= tstop; n_num++) {
	if (c_ptr->nodes[n_num]) {
	tipc_node_remove_router(c_ptr->nodes[n_num], router);
	}
	}
	}

	/**
	* tipc_cltr_multicast - multicast message to local nodes
	*/

	static void tipc_cltr_multicast(struct cluster c_ptr, struct sk_buff buf,
	u32 lower, u32 upper)
	{
	struct sk_buff *buf_copy;
	struct tipc_node *n_ptr;
	u32 n_num;
	u32 tstop;

	assert(lower <= upper);
	assert(((lower >= 1) && (lower <= tipc_max_nodes)) \|\|
	((lower >= LOWEST_SLAVE) && (lower <= tipc_highest_allowed_slave)));
	assert(((upper >= 1) && (upper <= tipc_max_nodes)) \|\|
	((upper >= LOWEST_SLAVE) && (upper <= tipc_highest_allowed_slave)));
	assert(in_own_cluster(c_ptr->addr));

	tstop = is_slave(upper) ? c_ptr->highest_slave : c_ptr->highest_node;
	if (tstop > upper)
	tstop = upper;
	for (n_num = lower; n_num <= tstop; n_num++) {
	n_ptr = c_ptr->nodes[n_num];
	if (n_ptr && tipc_node_has_active_links(n_ptr)) {
	buf_copy = skb_copy(buf, GFP_ATOMIC);
	if (buf_copy == NULL)
	break;
	msg_set_destnode(buf_msg(buf_copy), n_ptr->addr);
	tipc_link_send(buf_copy, n_ptr->addr, n_ptr->addr);
	}
	}
	buf_discard(buf);
	}

	/**
	* tipc_cltr_broadcast - broadcast message to all nodes within cluster
	*/

	void tipc_cltr_broadcast(struct sk_buff *buf)
	{
	struct sk_buff *buf_copy;
	struct cluster *c_ptr;
	struct tipc_node *n_ptr;
	u32 n_num;
	u32 tstart;
	u32 tstop;
	u32 node_type;

	if (tipc_mode == TIPC_NET_MODE) {
	c_ptr = tipc_cltr_find(tipc_own_addr);
	assert(in_own_cluster(c_ptr->addr)); /* For now */

	/* Send to standard nodes, then repeat loop sending to slaves */
	tstart = 1;
	tstop = c_ptr->highest_node;
	for (node_type = 1; node_type <= 2; node_type++) {
	for (n_num = tstart; n_num <= tstop; n_num++) {
	n_ptr = c_ptr->nodes[n_num];
	if (n_ptr && tipc_node_has_active_links(n_ptr)) {
	buf_copy = skb_copy(buf, GFP_ATOMIC);
	if (buf_copy == NULL)
	goto exit;
	msg_set_destnode(buf_msg(buf_copy),
	n_ptr->addr);
	tipc_link_send(buf_copy, n_ptr->addr,
	n_ptr->addr);
	}
	}
	tstart = LOWEST_SLAVE;
	tstop = c_ptr->highest_slave;
	}
	}
	exit:
	buf_discard(buf);
	}

	int tipc_cltr_init(void)
	{
	tipc_highest_allowed_slave = LOWEST_SLAVE + tipc_max_slaves;
	return tipc_cltr_create(tipc_own_addr) ? 0 : -ENOMEM;
	}