[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / tipc / name_distr.c

/*
 * net/tipc/name_distr.c: TIPC name distribution code
 * 
 * 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 "dbg.h"
#include "link.h"
#include "msg.h"
#include "name_distr.h"

#undef  DBG_OUTPUT
#define DBG_OUTPUT NULL

#define ITEM_SIZE sizeof(struct distr_item)

/**
 * struct distr_item - publication info distributed to other nodes
 * @type: name sequence type
 * @lower: name sequence lower bound
 * @upper: name sequence upper bound
 * @ref: publishing port reference
 * @key: publication key
 * 
 * ===> All fields are stored in network byte order. <===
 * 
 * First 3 fields identify (name or) name sequence being published.
 * Reference field uniquely identifies port that published name sequence.
 * Key field uniquely identifies publication, in the event a port has
 * multiple publications of the same name sequence.
 * 
 * Note: There is no field that identifies the publishing node because it is 
 * the same for all items contained within a publication message.
 */

struct distr_item {
	u32 type;
	u32 lower;
	u32 upper;
	u32 ref;
	u32 key;
};

/**
 * List of externally visible publications by this node -- 
 * that is, all publications having scope > TIPC_NODE_SCOPE.
 */

static LIST_HEAD(publ_root);
static u32 publ_cnt = 0;		

/**
 * publ_to_item - add publication info to a publication message
 */

static void publ_to_item(struct distr_item *i, struct publication *p)
{
	i->type = htonl(p->type);
	i->lower = htonl(p->lower);
	i->upper = htonl(p->upper);
	i->ref = htonl(p->ref);
	i->key = htonl(p->key);
	dbg("publ_to_item: %u, %u, %u\n", p->type, p->lower, p->upper);
}

/**
 * named_prepare_buf - allocate & initialize a publication message
 */

static struct sk_buff *named_prepare_buf(u32 type, u32 size, u32 dest)
{
	struct sk_buff *buf = buf_acquire(LONG_H_SIZE + size);  
	struct tipc_msg *msg;

	if (buf != NULL) {
		msg = buf_msg(buf);
		msg_init(msg, NAME_DISTRIBUTOR, type, TIPC_OK, 
			 LONG_H_SIZE, dest);
		msg_set_size(msg, LONG_H_SIZE + size);
	}
	return buf;
}

/**
 * tipc_named_publish - tell other nodes about a new publication by this node
 */

void tipc_named_publish(struct publication *publ)
{
	struct sk_buff *buf;
	struct distr_item *item;

	list_add(&publ->local_list, &publ_root);
	publ_cnt++;

	buf = named_prepare_buf(PUBLICATION, ITEM_SIZE, 0);
	if (!buf) {
		warn("Memory squeeze; failed to distribute publication\n");
		return;
	}

	item = (struct distr_item *)msg_data(buf_msg(buf));
	publ_to_item(item, publ);
	dbg("tipc_named_withdraw: broadcasting publish msg\n");
	tipc_cltr_broadcast(buf);
}

/**
 * tipc_named_withdraw - tell other nodes about a withdrawn publication by this node
 */

void tipc_named_withdraw(struct publication *publ)
{
	struct sk_buff *buf;
	struct distr_item *item;

	list_del(&publ->local_list);
	publ_cnt--;

	buf = named_prepare_buf(WITHDRAWAL, ITEM_SIZE, 0);
	if (!buf) {
		warn("Memory squeeze; failed to distribute withdrawal\n");
		return;
	}

	item = (struct distr_item *)msg_data(buf_msg(buf));
	publ_to_item(item, publ);
	dbg("tipc_named_withdraw: broadcasting withdraw msg\n");
	tipc_cltr_broadcast(buf);
}

/**
 * tipc_named_node_up - tell specified node about all publications by this node
 */

void tipc_named_node_up(unsigned long node)
{
	struct publication *publ;
	struct distr_item *item = NULL;
	struct sk_buff *buf = NULL;
	u32 left = 0;
	u32 rest;
	u32 max_item_buf;

	assert(in_own_cluster(node));
	read_lock_bh(&tipc_nametbl_lock); 
	max_item_buf = TIPC_MAX_USER_MSG_SIZE / ITEM_SIZE;
	max_item_buf *= ITEM_SIZE;
	rest = publ_cnt * ITEM_SIZE;

	list_for_each_entry(publ, &publ_root, local_list) {
		if (!buf) {
			left = (rest <= max_item_buf) ? rest : max_item_buf;
			rest -= left;
			buf = named_prepare_buf(PUBLICATION, left, node);       
			if (buf == NULL) {
				warn("Memory Squeeze; could not send publication\n");
				goto exit;
			}
			item = (struct distr_item *)msg_data(buf_msg(buf));
		}
		publ_to_item(item, publ);
		item++;
		left -= ITEM_SIZE;
		if (!left) {
			msg_set_link_selector(buf_msg(buf), node);
			dbg("tipc_named_node_up: sending publish msg to "
			    "<%u.%u.%u>\n", tipc_zone(node), 
			    tipc_cluster(node), tipc_node(node));
			tipc_link_send(buf, node, node);
			buf = NULL;
		}
	}
exit:
	read_unlock_bh(&tipc_nametbl_lock); 
}

/**
 * node_is_down - remove publication associated with a failed node
 * 
 * Invoked for each publication issued by a newly failed node.  
 * Removes publication structure from name table & deletes it.
 * In rare cases the link may have come back up again when this
 * function is called, and we have two items representing the same
 * publication. Nudge this item's key to distinguish it from the other.
 * (Note: Publication's node subscription is already unsubscribed.)
 */

static void node_is_down(struct publication *publ)
{
	struct publication *p;
        write_lock_bh(&tipc_nametbl_lock);
	dbg("node_is_down: withdrawing %u, %u, %u\n", 
	    publ->type, publ->lower, publ->upper);
        publ->key += 1222345;
	p = tipc_nametbl_remove_publ(publ->type, publ->lower, 
				     publ->node, publ->ref, publ->key);
        assert(p == publ);
	write_unlock_bh(&tipc_nametbl_lock);
	kfree(publ);
}

/**
 * tipc_named_recv - process name table update message sent by another node
 */

void tipc_named_recv(struct sk_buff *buf)
{
	struct publication *publ;
	struct tipc_msg *msg = buf_msg(buf);
	struct distr_item *item = (struct distr_item *)msg_data(msg);
	u32 count = msg_data_sz(msg) / ITEM_SIZE;

	write_lock_bh(&tipc_nametbl_lock); 
	while (count--) {
		if (msg_type(msg) == PUBLICATION) {
			dbg("tipc_named_recv: got publication for %u, %u, %u\n", 
			    ntohl(item->type), ntohl(item->lower),
			    ntohl(item->upper));
			publ = tipc_nametbl_insert_publ(ntohl(item->type), 
							ntohl(item->lower),
							ntohl(item->upper),
							TIPC_CLUSTER_SCOPE,
							msg_orignode(msg), 
							ntohl(item->ref),
							ntohl(item->key));
			if (publ) {
				tipc_nodesub_subscribe(&publ->subscr, 
						       msg_orignode(msg), 
						       publ,
						       (net_ev_handler)node_is_down);
			}
		} else if (msg_type(msg) == WITHDRAWAL) {
			dbg("tipc_named_recv: got withdrawl for %u, %u, %u\n", 
			    ntohl(item->type), ntohl(item->lower),
			    ntohl(item->upper));
			publ = tipc_nametbl_remove_publ(ntohl(item->type),
							ntohl(item->lower),
							msg_orignode(msg),
							ntohl(item->ref),
							ntohl(item->key));

			if (publ) {
				tipc_nodesub_unsubscribe(&publ->subscr);
        			kfree(publ);
			}
		} else {
			warn("tipc_named_recv: unknown msg\n");
		}
		item++;
	}
	write_unlock_bh(&tipc_nametbl_lock); 
	buf_discard(buf);
}

/**
 * tipc_named_reinit - re-initialize local publication list
 * 
 * This routine is called whenever TIPC networking is (re)enabled.
 * All existing publications by this node that have "cluster" or "zone" scope
 * are updated to reflect the node's current network address.
 * (If the node's address is unchanged, the update loop terminates immediately.)
 */

void tipc_named_reinit(void)
{
	struct publication *publ;

	write_lock_bh(&tipc_nametbl_lock); 
	list_for_each_entry(publ, &publ_root, local_list) {
		if (publ->node == tipc_own_addr)
			break;
		publ->node = tipc_own_addr;
	}
	write_unlock_bh(&tipc_nametbl_lock); 
}
Commit	Line	Data
b97bf3fd PL	1	/*
	2	* net/tipc/name_distr.c: TIPC name distribution code
	3	*
593a5f22	4	* Copyright (c) 2000-2006, Ericsson AB
b97bf3fd	5	* Copyright (c) 2005, Wind River Systems
b97bf3fd PL	6	* All rights reserved.
b97bf3fd PL	7	*
9ea1fd3c	8	* Redistribution and use in source and binary forms, with or without
b97bf3fd PL	9	* modification, are permitted provided that the following conditions are met:
b97bf3fd PL	10	*
9ea1fd3c PL	11	* 1. Redistributions of source code must retain the above copyright
	12	* notice, this list of conditions and the following disclaimer.
	13	* 2. Redistributions in binary form must reproduce the above copyright
	14	* notice, this list of conditions and the following disclaimer in the
	15	* documentation and/or other materials provided with the distribution.
	16	* 3. Neither the names of the copyright holders nor the names of its
	17	* contributors may be used to endorse or promote products derived from
	18	* this software without specific prior written permission.
b97bf3fd	19	*
9ea1fd3c PL	20	* Alternatively, this software may be distributed under the terms of the
	21	* GNU General Public License ("GPL") version 2 as published by the Free
	22	* Software Foundation.
	23	*
	24	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
	25	* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	26	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	27	* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
	28	* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	29	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	30	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	31	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
	32	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	33	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
b97bf3fd PL	34	* POSSIBILITY OF SUCH DAMAGE.
	35	*/
	36
	37	#include "core.h"
	38	#include "cluster.h"
	39	#include "dbg.h"
	40	#include "link.h"
	41	#include "msg.h"
	42	#include "name_distr.h"
	43
	44	#undef DBG_OUTPUT
	45	#define DBG_OUTPUT NULL
	46
	47	#define ITEM_SIZE sizeof(struct distr_item)
	48
	49	/**
	50	* struct distr_item - publication info distributed to other nodes
	51	* @type: name sequence type
	52	* @lower: name sequence lower bound
	53	* @upper: name sequence upper bound
	54	* @ref: publishing port reference
	55	* @key: publication key
	56	*
	57	* ===> All fields are stored in network byte order. <===
	58	*
	59	* First 3 fields identify (name or) name sequence being published.
	60	* Reference field uniquely identifies port that published name sequence.
	61	* Key field uniquely identifies publication, in the event a port has
	62	* multiple publications of the same name sequence.
	63	*
	64	* Note: There is no field that identifies the publishing node because it is
	65	* the same for all items contained within a publication message.
	66	*/
	67
	68	struct distr_item {
	69	u32 type;
	70	u32 lower;
	71	u32 upper;
	72	u32 ref;
	73	u32 key;
	74	};
	75
	76	/**
	77	* List of externally visible publications by this node --
	78	* that is, all publications having scope > TIPC_NODE_SCOPE.
	79	*/
	80
	81	static LIST_HEAD(publ_root);
	82	static u32 publ_cnt = 0;
	83
	84	/**
	85	* publ_to_item - add publication info to a publication message
	86	*/
	87
	88	static void publ_to_item(struct distr_item i, struct publication p)
	89	{
	90	i->type = htonl(p->type);
	91	i->lower = htonl(p->lower);
	92	i->upper = htonl(p->upper);
	93	i->ref = htonl(p->ref);
	94	i->key = htonl(p->key);
	95	dbg("publ_to_item: %u, %u, %u\n", p->type, p->lower, p->upper);
	96	}
	97
98	/**
99	* named_prepare_buf - allocate & initialize a publication message
100	*/
101
102	static struct sk_buff *named_prepare_buf(u32 type, u32 size, u32 dest)
103	{
104	struct sk_buff *buf = buf_acquire(LONG_H_SIZE + size);
105	struct tipc_msg *msg;
106
107	if (buf != NULL) {
108	msg = buf_msg(buf);
109	msg_init(msg, NAME_DISTRIBUTOR, type, TIPC_OK,
110	LONG_H_SIZE, dest);
111	msg_set_size(msg, LONG_H_SIZE + size);
112	}
113	return buf;
114	}
115
116	/**
4323add6	117	* tipc_named_publish - tell other nodes about a new publication by this node
b97bf3fd PL	118	*/
b97bf3fd PL	119
4323add6	120	void tipc_named_publish(struct publication *publ)
b97bf3fd PL	121	{
	122	struct sk_buff *buf;
	123	struct distr_item *item;
	124
	125	list_add(&publ->local_list, &publ_root);
	126	publ_cnt++;
	127
	128	buf = named_prepare_buf(PUBLICATION, ITEM_SIZE, 0);
	129	if (!buf) {
	130	warn("Memory squeeze; failed to distribute publication\n");
	131	return;
	132	}
	133
	134	item = (struct distr_item *)msg_data(buf_msg(buf));
	135	publ_to_item(item, publ);
4323add6 PL	136	dbg("tipc_named_withdraw: broadcasting publish msg\n");
4323add6 PL	137	tipc_cltr_broadcast(buf);
b97bf3fd PL	138	}
	139
	140	/**
4323add6	141	* tipc_named_withdraw - tell other nodes about a withdrawn publication by this node
b97bf3fd PL	142	*/
b97bf3fd PL	143
4323add6	144	void tipc_named_withdraw(struct publication *publ)
b97bf3fd PL	145	{
	146	struct sk_buff *buf;
	147	struct distr_item *item;
	148
	149	list_del(&publ->local_list);
	150	publ_cnt--;
	151
	152	buf = named_prepare_buf(WITHDRAWAL, ITEM_SIZE, 0);
	153	if (!buf) {
	154	warn("Memory squeeze; failed to distribute withdrawal\n");
	155	return;
	156	}
	157
	158	item = (struct distr_item *)msg_data(buf_msg(buf));
	159	publ_to_item(item, publ);
4323add6 PL	160	dbg("tipc_named_withdraw: broadcasting withdraw msg\n");
4323add6 PL	161	tipc_cltr_broadcast(buf);
b97bf3fd PL	162	}
	163
	164	/**
4323add6	165	* tipc_named_node_up - tell specified node about all publications by this node
b97bf3fd PL	166	*/
b97bf3fd PL	167
4323add6	168	void tipc_named_node_up(unsigned long node)
b97bf3fd PL	169	{
b97bf3fd PL	170	struct publication *publ;
1fc54d8f SR	171	struct distr_item *item = NULL;
1fc54d8f SR	172	struct sk_buff *buf = NULL;
b97bf3fd PL	173	u32 left = 0;
	174	u32 rest;
	175	u32 max_item_buf;
	176
	177	assert(in_own_cluster(node));
4323add6	178	read_lock_bh(&tipc_nametbl_lock);
b97bf3fd PL	179	max_item_buf = TIPC_MAX_USER_MSG_SIZE / ITEM_SIZE;
	180	max_item_buf *= ITEM_SIZE;
	181	rest = publ_cnt * ITEM_SIZE;
	182
	183	list_for_each_entry(publ, &publ_root, local_list) {
	184	if (!buf) {
	185	left = (rest <= max_item_buf) ? rest : max_item_buf;
	186	rest -= left;
	187	buf = named_prepare_buf(PUBLICATION, left, node);
	188	if (buf == NULL) {
	189	warn("Memory Squeeze; could not send publication\n");
	190	goto exit;
	191	}
	192	item = (struct distr_item *)msg_data(buf_msg(buf));
	193	}
	194	publ_to_item(item, publ);
	195	item++;
	196	left -= ITEM_SIZE;
	197	if (!left) {
	198	msg_set_link_selector(buf_msg(buf), node);
4323add6	199	dbg("tipc_named_node_up: sending publish msg to "
b97bf3fd PL	200	"<%u.%u.%u>\n", tipc_zone(node),
b97bf3fd PL	201	tipc_cluster(node), tipc_node(node));
4323add6	202	tipc_link_send(buf, node, node);
1fc54d8f	203	buf = NULL;
b97bf3fd PL	204	}
	205	}
	206	exit:
4323add6	207	read_unlock_bh(&tipc_nametbl_lock);
b97bf3fd PL	208	}
	209
	210	/**
	211	* node_is_down - remove publication associated with a failed node
	212	*
	213	* Invoked for each publication issued by a newly failed node.
	214	* Removes publication structure from name table & deletes it.
	215	* In rare cases the link may have come back up again when this
	216	* function is called, and we have two items representing the same
	217	* publication. Nudge this item's key to distinguish it from the other.
	218	* (Note: Publication's node subscription is already unsubscribed.)
	219	*/
	220
	221	static void node_is_down(struct publication *publ)
	222	{
	223	struct publication *p;
4323add6	224	write_lock_bh(&tipc_nametbl_lock);
b97bf3fd PL	225	dbg("node_is_down: withdrawing %u, %u, %u\n",
	226	publ->type, publ->lower, publ->upper);
	227	publ->key += 1222345;
4323add6 PL	228	p = tipc_nametbl_remove_publ(publ->type, publ->lower,
4323add6 PL	229	publ->node, publ->ref, publ->key);
b97bf3fd	230	assert(p == publ);
4323add6	231	write_unlock_bh(&tipc_nametbl_lock);
63903ca6	232	kfree(publ);
b97bf3fd PL	233	}
	234
	235	/**
4323add6	236	* tipc_named_recv - process name table update message sent by another node
b97bf3fd PL	237	*/
b97bf3fd PL	238
4323add6	239	void tipc_named_recv(struct sk_buff *buf)
b97bf3fd PL	240	{
	241	struct publication *publ;
	242	struct tipc_msg *msg = buf_msg(buf);
	243	struct distr_item item = (struct distr_item )msg_data(msg);
	244	u32 count = msg_data_sz(msg) / ITEM_SIZE;
	245
4323add6	246	write_lock_bh(&tipc_nametbl_lock);
b97bf3fd PL	247	while (count--) {
b97bf3fd PL	248	if (msg_type(msg) == PUBLICATION) {
4323add6	249	dbg("tipc_named_recv: got publication for %u, %u, %u\n",
b97bf3fd PL	250	ntohl(item->type), ntohl(item->lower),
b97bf3fd PL	251	ntohl(item->upper));
4323add6 PL	252	publ = tipc_nametbl_insert_publ(ntohl(item->type),
	253	ntohl(item->lower),
	254	ntohl(item->upper),
	255	TIPC_CLUSTER_SCOPE,
	256	msg_orignode(msg),
	257	ntohl(item->ref),
	258	ntohl(item->key));
b97bf3fd	259	if (publ) {
4323add6 PL	260	tipc_nodesub_subscribe(&publ->subscr,
	261	msg_orignode(msg),
	262	publ,
	263	(net_ev_handler)node_is_down);
b97bf3fd PL	264	}
b97bf3fd PL	265	} else if (msg_type(msg) == WITHDRAWAL) {
4323add6	266	dbg("tipc_named_recv: got withdrawl for %u, %u, %u\n",
b97bf3fd PL	267	ntohl(item->type), ntohl(item->lower),
b97bf3fd PL	268	ntohl(item->upper));
4323add6 PL	269	publ = tipc_nametbl_remove_publ(ntohl(item->type),
	270	ntohl(item->lower),
	271	msg_orignode(msg),
	272	ntohl(item->ref),
	273	ntohl(item->key));
b97bf3fd PL	274
b97bf3fd PL	275	if (publ) {
4323add6	276	tipc_nodesub_unsubscribe(&publ->subscr);
b97bf3fd PL	277	kfree(publ);
	278	}
	279	} else {
4323add6	280	warn("tipc_named_recv: unknown msg\n");
b97bf3fd PL	281	}
	282	item++;
	283	}
4323add6	284	write_unlock_bh(&tipc_nametbl_lock);
b97bf3fd PL	285	buf_discard(buf);
	286	}
	287
	288	/**
4323add6	289	* tipc_named_reinit - re-initialize local publication list
b97bf3fd PL	290	*
	291	* This routine is called whenever TIPC networking is (re)enabled.
	292	* All existing publications by this node that have "cluster" or "zone" scope
	293	* are updated to reflect the node's current network address.
	294	* (If the node's address is unchanged, the update loop terminates immediately.)
	295	*/
	296
4323add6	297	void tipc_named_reinit(void)
b97bf3fd PL	298	{
	299	struct publication *publ;
	300
4323add6	301	write_lock_bh(&tipc_nametbl_lock);
b97bf3fd PL	302	list_for_each_entry(publ, &publ_root, local_list) {
	303	if (publ->node == tipc_own_addr)
	304	break;
	305	publ->node = tipc_own_addr;
	306	}
4323add6	307	write_unlock_bh(&tipc_nametbl_lock);
b97bf3fd	308	}