[deliverable/linux.git] / net / tipc / name_distr.c

/*
 * net/tipc/name_distr.c: TIPC name distribution code
 * 
 * Copyright (c) 2003-2005, Ericsson Research Canada
 * 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 "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;
}

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

void 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("named_withdraw: broadcasting publish msg\n");
	cluster_broadcast(buf);
}

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 * named_withdraw - tell other nodes about a withdrawn publication by this node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

void 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("named_withdraw: broadcasting withdraw msg\n");
	cluster_broadcast(buf);
}

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

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

	assert(in_own_cluster(node));
	read_lock_bh(&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("named_node_up: sending publish msg to "
			    "<%u.%u.%u>\n", tipc_zone(node), 
			    tipc_cluster(node), tipc_node(node));
			link_send(buf, node, node);
			buf = 0;
		}
	}
exit:
	read_unlock_bh(&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(&nametbl_lock);
	dbg("node_is_down: withdrawing %u, %u, %u\n", 
	    publ->type, publ->lower, publ->upper);
        publ->key += 1222345;
	p = nametbl_remove_publ(publ->type, publ->lower, 
				publ->node, publ->ref, publ->key);
        assert(p == publ);
	write_unlock_bh(&nametbl_lock);
	if (publ)
		kfree(publ);
}

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

void 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(&nametbl_lock); 
	while (count--) {
		if (msg_type(msg) == PUBLICATION) {
			dbg("named_recv: got publication for %u, %u, %u\n", 
			    ntohl(item->type), ntohl(item->lower),
			    ntohl(item->upper));
			publ = 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) {
				nodesub_subscribe(&publ->subscr, 
						  msg_orignode(msg), 
						  publ,
						  (net_ev_handler)node_is_down);
			}
		} else if (msg_type(msg) == WITHDRAWAL) {
			dbg("named_recv: got withdrawl for %u, %u, %u\n", 
			    ntohl(item->type), ntohl(item->lower),
			    ntohl(item->upper));
			publ = nametbl_remove_publ(ntohl(item->type),
						   ntohl(item->lower),
						   msg_orignode(msg),
						   ntohl(item->ref),
						   ntohl(item->key));

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

/**
 * 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 named_reinit(void)
{
	struct publication *publ;

	write_lock_bh(&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(&nametbl_lock); 
}
Commit	Line	Data
b97bf3fd PL	1	/*
	2	* net/tipc/name_distr.c: TIPC name distribution code
	3	*
	4	* Copyright (c) 2003-2005, Ericsson Research Canada
	5	* Copyright (c) 2005, Wind River Systems
	6	* Copyright (c) 2005-2006, Ericsson AB
	7	* All rights reserved.
	8	*
	9	* Redistribution and use in source and binary forms, with or without
	10	* modification, are permitted provided that the following conditions are met:
	11	*
	12	* Redistributions of source code must retain the above copyright notice, this
	13	* list of conditions and the following disclaimer.
	14	* Redistributions in binary form must reproduce the above copyright notice,
	15	* this list of conditions and the following disclaimer in the documentation
	16	* and/or other materials provided with the distribution.
	17	* Neither the names of the copyright holders nor the names of its
	18	* contributors may be used to endorse or promote products derived from this
	19	* software without specific prior written permission.
	20	*
	21	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
	22	* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	23	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	24	* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
	25	* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	26	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	27	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	28	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
	29	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	30	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
	31	* POSSIBILITY OF SUCH DAMAGE.
	32	*/
	33
	34	#include "core.h"
	35	#include "cluster.h"
	36	#include "dbg.h"
	37	#include "link.h"
	38	#include "msg.h"
	39	#include "name_distr.h"
	40
	41	#undef DBG_OUTPUT
	42	#define DBG_OUTPUT NULL
	43
	44	#define ITEM_SIZE sizeof(struct distr_item)
	45
	46	/**
	47	* struct distr_item - publication info distributed to other nodes
	48	* @type: name sequence type
	49	* @lower: name sequence lower bound
	50	* @upper: name sequence upper bound
	51	* @ref: publishing port reference
	52	* @key: publication key
	53	*
	54	* ===> All fields are stored in network byte order. <===
	55	*
	56	* First 3 fields identify (name or) name sequence being published.
	57	* Reference field uniquely identifies port that published name sequence.
	58	* Key field uniquely identifies publication, in the event a port has
	59	* multiple publications of the same name sequence.
	60	*
	61	* Note: There is no field that identifies the publishing node because it is
	62	* the same for all items contained within a publication message.
	63	*/
	64
65	struct distr_item {
66	u32 type;
67	u32 lower;
68	u32 upper;
69	u32 ref;
70	u32 key;
71	};
72
73	/**
74	* List of externally visible publications by this node --
75	* that is, all publications having scope > TIPC_NODE_SCOPE.
76	*/
77
78	static LIST_HEAD(publ_root);
79	static u32 publ_cnt = 0;
80
81	/**
82	* publ_to_item - add publication info to a publication message
83	*/
84
85	static void publ_to_item(struct distr_item i, struct publication p)
86	{
87	i->type = htonl(p->type);
88	i->lower = htonl(p->lower);
89	i->upper = htonl(p->upper);
90	i->ref = htonl(p->ref);
91	i->key = htonl(p->key);
92	dbg("publ_to_item: %u, %u, %u\n", p->type, p->lower, p->upper);
93	}
94
95	/**
96	* named_prepare_buf - allocate & initialize a publication message
97	*/
98
99	static struct sk_buff *named_prepare_buf(u32 type, u32 size, u32 dest)
100	{
101	struct sk_buff *buf = buf_acquire(LONG_H_SIZE + size);
102	struct tipc_msg *msg;
103
104	if (buf != NULL) {
105	msg = buf_msg(buf);
106	msg_init(msg, NAME_DISTRIBUTOR, type, TIPC_OK,
107	LONG_H_SIZE, dest);
108	msg_set_size(msg, LONG_H_SIZE + size);
109	}
110	return buf;
111	}
112
113	/**
114	* named_publish - tell other nodes about a new publication by this node
115	*/
116
117	void named_publish(struct publication *publ)
118	{
119	struct sk_buff *buf;
120	struct distr_item *item;
121
122	list_add(&publ->local_list, &publ_root);
123	publ_cnt++;
124
125	buf = named_prepare_buf(PUBLICATION, ITEM_SIZE, 0);
126	if (!buf) {
127	warn("Memory squeeze; failed to distribute publication\n");
128	return;
129	}
130
131	item = (struct distr_item *)msg_data(buf_msg(buf));
132	publ_to_item(item, publ);
133	dbg("named_withdraw: broadcasting publish msg\n");
134	cluster_broadcast(buf);
135	}
136
137	/**
138	* named_withdraw - tell other nodes about a withdrawn publication by this node
139	*/
140
141	void named_withdraw(struct publication *publ)
142	{
143	struct sk_buff *buf;
144	struct distr_item *item;
145
146	list_del(&publ->local_list);
147	publ_cnt--;
148
149	buf = named_prepare_buf(WITHDRAWAL, ITEM_SIZE, 0);
150	if (!buf) {
151	warn("Memory squeeze; failed to distribute withdrawal\n");
152	return;
153	}
154
155	item = (struct distr_item *)msg_data(buf_msg(buf));
156	publ_to_item(item, publ);
157	dbg("named_withdraw: broadcasting withdraw msg\n");
158	cluster_broadcast(buf);
159	}
160
161	/**
162	* named_node_up - tell specified node about all publications by this node
163	*/
164
165	void named_node_up(unsigned long node)
166	{
167	struct publication *publ;
168	struct distr_item *item = 0;
169	struct sk_buff *buf = 0;
170	u32 left = 0;
171	u32 rest;
172	u32 max_item_buf;
173
174	assert(in_own_cluster(node));
175	read_lock_bh(&nametbl_lock);
176	max_item_buf = TIPC_MAX_USER_MSG_SIZE / ITEM_SIZE;
177	max_item_buf *= ITEM_SIZE;
178	rest = publ_cnt * ITEM_SIZE;
179
180	list_for_each_entry(publ, &publ_root, local_list) {
181	if (!buf) {
182	left = (rest <= max_item_buf) ? rest : max_item_buf;
183	rest -= left;
184	buf = named_prepare_buf(PUBLICATION, left, node);
185	if (buf == NULL) {
186	warn("Memory Squeeze; could not send publication\n");
187	goto exit;
188	}
189	item = (struct distr_item *)msg_data(buf_msg(buf));
190	}
191	publ_to_item(item, publ);
192	item++;
193	left -= ITEM_SIZE;
194	if (!left) {
195	msg_set_link_selector(buf_msg(buf), node);
196	dbg("named_node_up: sending publish msg to "
197	"<%u.%u.%u>\n", tipc_zone(node),
198	tipc_cluster(node), tipc_node(node));
199	link_send(buf, node, node);
200	buf = 0;
201	}
202	}
203	exit:
204	read_unlock_bh(&nametbl_lock);
205	}
206
207	/**
208	* node_is_down - remove publication associated with a failed node
209	*
210	* Invoked for each publication issued by a newly failed node.
211	* Removes publication structure from name table & deletes it.
212	* In rare cases the link may have come back up again when this
213	* function is called, and we have two items representing the same
214	* publication. Nudge this item's key to distinguish it from the other.
215	* (Note: Publication's node subscription is already unsubscribed.)
216	*/
217
218	static void node_is_down(struct publication *publ)
219	{
220	struct publication *p;
221	write_lock_bh(&nametbl_lock);
222	dbg("node_is_down: withdrawing %u, %u, %u\n",
223	publ->type, publ->lower, publ->upper);
224	publ->key += 1222345;
225	p = nametbl_remove_publ(publ->type, publ->lower,
226	publ->node, publ->ref, publ->key);
227	assert(p == publ);
228	write_unlock_bh(&nametbl_lock);
229	if (publ)
230	kfree(publ);
231	}
232
233	/**
234	* named_recv - process name table update message sent by another node
235	*/
236
237	void named_recv(struct sk_buff *buf)
238	{
239	struct publication *publ;
240	struct tipc_msg *msg = buf_msg(buf);
241	struct distr_item item = (struct distr_item )msg_data(msg);
242	u32 count = msg_data_sz(msg) / ITEM_SIZE;
243
244	write_lock_bh(&nametbl_lock);
245	while (count--) {
246	if (msg_type(msg) == PUBLICATION) {
247	dbg("named_recv: got publication for %u, %u, %u\n",
248	ntohl(item->type), ntohl(item->lower),
249	ntohl(item->upper));
250	publ = nametbl_insert_publ(ntohl(item->type),
251	ntohl(item->lower),
252	ntohl(item->upper),
253	TIPC_CLUSTER_SCOPE,
254	msg_orignode(msg),
255	ntohl(item->ref),
256	ntohl(item->key));
257	if (publ) {
258	nodesub_subscribe(&publ->subscr,
259	msg_orignode(msg),
260	publ,
261	(net_ev_handler)node_is_down);
262	}
263	} else if (msg_type(msg) == WITHDRAWAL) {
264	dbg("named_recv: got withdrawl for %u, %u, %u\n",
265	ntohl(item->type), ntohl(item->lower),
266	ntohl(item->upper));
267	publ = nametbl_remove_publ(ntohl(item->type),
268	ntohl(item->lower),
269	msg_orignode(msg),
270	ntohl(item->ref),
271	ntohl(item->key));
272
273	if (publ) {
274	nodesub_unsubscribe(&publ->subscr);
275	kfree(publ);
276	}
277	} else {
278	warn("named_recv: unknown msg\n");
279	}
280	item++;
281	}
282	write_unlock_bh(&nametbl_lock);
283	buf_discard(buf);
284	}
285
286	/**
287	* named_reinit - re-initialize local publication list
288	*
289	* This routine is called whenever TIPC networking is (re)enabled.
290	* All existing publications by this node that have "cluster" or "zone" scope
291	* are updated to reflect the node's current network address.
292	* (If the node's address is unchanged, the update loop terminates immediately.)
293	*/
294
295	void named_reinit(void)
296	{
297	struct publication *publ;
298
299	write_lock_bh(&nametbl_lock);
300	list_for_each_entry(publ, &publ_root, local_list) {
301	if (publ->node == tipc_own_addr)
302	break;
303	publ->node = tipc_own_addr;
304	}
305	write_unlock_bh(&nametbl_lock);
306	}