name_distr.c 8.87 KB
Newer Older
Per Liden's avatar
Per Liden committed
1
2
/*
 * net/tipc/name_distr.c: TIPC name distribution code
3
 *
4
 * Copyright (c) 2000-2006, Ericsson AB
Per Liden's avatar
Per Liden committed
5
6
7
 * Copyright (c) 2005, Wind River Systems
 * All rights reserved.
 *
Per Liden's avatar
Per Liden committed
8
 * Redistribution and use in source and binary forms, with or without
Per Liden's avatar
Per Liden committed
9
10
 * modification, are permitted provided that the following conditions are met:
 *
Per Liden's avatar
Per Liden committed
11
12
13
14
15
16
17
18
 * 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.
Per Liden's avatar
Per Liden committed
19
 *
Per Liden's avatar
Per Liden committed
20
21
22
23
24
25
26
27
28
29
30
31
32
33
 * 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
Per Liden's avatar
Per Liden committed
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include "core.h"
#include "link.h"
#include "name_distr.h"

#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
50
 *
Per Liden's avatar
Per Liden committed
51
 * ===> All fields are stored in network byte order. <===
52
 *
Per Liden's avatar
Per Liden committed
53
54
55
56
 * 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.
57
58
 *
 * Note: There is no field that identifies the publishing node because it is
Per Liden's avatar
Per Liden committed
59
60
61
62
 * the same for all items contained within a publication message.
 */

struct distr_item {
Al Viro's avatar
Al Viro committed
63
64
65
66
67
	__be32 type;
	__be32 lower;
	__be32 upper;
	__be32 ref;
	__be32 key;
Per Liden's avatar
Per Liden committed
68
69
70
};

/**
71
 * List of externally visible publications by this node --
Per Liden's avatar
Per Liden committed
72
73
74
75
 * that is, all publications having scope > TIPC_NODE_SCOPE.
 */

static LIST_HEAD(publ_root);
76
static u32 publ_cnt;
Per Liden's avatar
Per Liden committed
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96

/**
 * 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);
}

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

static struct sk_buff *named_prepare_buf(u32 type, u32 size, u32 dest)
{
97
	struct sk_buff *buf = tipc_buf_acquire(LONG_H_SIZE + size);
Per Liden's avatar
Per Liden committed
98
99
100
101
	struct tipc_msg *msg;

	if (buf != NULL) {
		msg = buf_msg(buf);
102
		tipc_msg_init(msg, NAME_DISTRIBUTOR, type, LONG_H_SIZE, dest);
Per Liden's avatar
Per Liden committed
103
104
105
106
107
		msg_set_size(msg, LONG_H_SIZE + size);
	}
	return buf;
}

108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
static void named_cluster_distribute(struct sk_buff *buf)
{
	struct sk_buff *buf_copy;
	struct tipc_node *n_ptr;
	u32 n_num;

	for (n_num = 1; n_num <= tipc_net.highest_node; n_num++) {
		n_ptr = tipc_net.nodes[n_num];
		if (n_ptr && tipc_node_has_active_links(n_ptr)) {
			buf_copy = skb_copy(buf, GFP_ATOMIC);
			if (!buf_copy)
				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);
}

Per Liden's avatar
Per Liden committed
128
/**
129
 * tipc_named_publish - tell other nodes about a new publication by this node
Per Liden's avatar
Per Liden committed
130
131
 */

132
void tipc_named_publish(struct publication *publ)
Per Liden's avatar
Per Liden committed
133
134
135
136
{
	struct sk_buff *buf;
	struct distr_item *item;

137
	list_add_tail(&publ->local_list, &publ_root);
Per Liden's avatar
Per Liden committed
138
139
140
141
	publ_cnt++;

	buf = named_prepare_buf(PUBLICATION, ITEM_SIZE, 0);
	if (!buf) {
142
		warn("Publication distribution failure\n");
Per Liden's avatar
Per Liden committed
143
144
145
146
147
		return;
	}

	item = (struct distr_item *)msg_data(buf_msg(buf));
	publ_to_item(item, publ);
148
	named_cluster_distribute(buf);
Per Liden's avatar
Per Liden committed
149
150
151
}

/**
152
 * tipc_named_withdraw - tell other nodes about a withdrawn publication by this node
Per Liden's avatar
Per Liden committed
153
154
 */

155
void tipc_named_withdraw(struct publication *publ)
Per Liden's avatar
Per Liden committed
156
157
158
159
160
161
162
163
164
{
	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) {
165
		warn("Withdrawl distribution failure\n");
Per Liden's avatar
Per Liden committed
166
167
168
169
170
		return;
	}

	item = (struct distr_item *)msg_data(buf_msg(buf));
	publ_to_item(item, publ);
171
	named_cluster_distribute(buf);
Per Liden's avatar
Per Liden committed
172
173
174
}

/**
175
 * tipc_named_node_up - tell specified node about all publications by this node
Per Liden's avatar
Per Liden committed
176
177
 */

178
void tipc_named_node_up(unsigned long node)
Per Liden's avatar
Per Liden committed
179
180
{
	struct publication *publ;
181
182
	struct distr_item *item = NULL;
	struct sk_buff *buf = NULL;
Per Liden's avatar
Per Liden committed
183
184
185
186
	u32 left = 0;
	u32 rest;
	u32 max_item_buf;

187
	read_lock_bh(&tipc_nametbl_lock);
Per Liden's avatar
Per Liden committed
188
189
190
191
192
193
194
195
	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;
196
			buf = named_prepare_buf(PUBLICATION, left, node);
197
198
			if (!buf) {
				warn("Bulk publication distribution failure\n");
Per Liden's avatar
Per Liden committed
199
200
201
202
203
204
205
206
207
				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);
208
			tipc_link_send(buf, node, node);
209
			buf = NULL;
Per Liden's avatar
Per Liden committed
210
211
212
		}
	}
exit:
213
	read_unlock_bh(&tipc_nametbl_lock);
Per Liden's avatar
Per Liden committed
214
215
216
217
}

/**
 * node_is_down - remove publication associated with a failed node
218
219
 *
 * Invoked for each publication issued by a newly failed node.
Per Liden's avatar
Per Liden committed
220
221
222
223
224
225
226
227
228
229
 * 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;
230

231
232
233
	write_lock_bh(&tipc_nametbl_lock);
	publ->key += 1222345;
	p = tipc_nametbl_remove_publ(publ->type, publ->lower,
234
235
				     publ->node, publ->ref, publ->key);
	write_unlock_bh(&tipc_nametbl_lock);
236

237
	if (p != publ) {
238
239
240
241
242
		err("Unable to remove publication from failed node\n"
		    "(type=%u, lower=%u, node=0x%x, ref=%u, key=%u)\n",
		    publ->type, publ->lower, publ->node, publ->ref, publ->key);
	}

243
	kfree(p);
Per Liden's avatar
Per Liden committed
244
245
246
}

/**
247
 * tipc_named_recv - process name table update message sent by another node
Per Liden's avatar
Per Liden committed
248
249
 */

250
void tipc_named_recv(struct sk_buff *buf)
Per Liden's avatar
Per Liden committed
251
252
253
254
255
256
{
	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;

257
	write_lock_bh(&tipc_nametbl_lock);
Per Liden's avatar
Per Liden committed
258
259
	while (count--) {
		if (msg_type(msg) == PUBLICATION) {
260
			publ = tipc_nametbl_insert_publ(ntohl(item->type),
261
262
263
							ntohl(item->lower),
							ntohl(item->upper),
							TIPC_CLUSTER_SCOPE,
264
							msg_orignode(msg),
265
266
							ntohl(item->ref),
							ntohl(item->key));
Per Liden's avatar
Per Liden committed
267
			if (publ) {
268
269
				tipc_nodesub_subscribe(&publ->subscr,
						       msg_orignode(msg),
270
271
						       publ,
						       (net_ev_handler)node_is_down);
Per Liden's avatar
Per Liden committed
272
273
			}
		} else if (msg_type(msg) == WITHDRAWAL) {
274
275
276
277
278
			publ = tipc_nametbl_remove_publ(ntohl(item->type),
							ntohl(item->lower),
							msg_orignode(msg),
							ntohl(item->ref),
							ntohl(item->key));
Per Liden's avatar
Per Liden committed
279
280

			if (publ) {
281
				tipc_nodesub_unsubscribe(&publ->subscr);
282
				kfree(publ);
283
284
285
286
287
288
			} else {
				err("Unable to remove publication by node 0x%x\n"
				    "(type=%u, lower=%u, ref=%u, key=%u)\n",
				    msg_orignode(msg),
				    ntohl(item->type), ntohl(item->lower),
				    ntohl(item->ref), ntohl(item->key));
Per Liden's avatar
Per Liden committed
289
290
			}
		} else {
291
			warn("Unrecognized name table message received\n");
Per Liden's avatar
Per Liden committed
292
293
294
		}
		item++;
	}
295
	write_unlock_bh(&tipc_nametbl_lock);
Per Liden's avatar
Per Liden committed
296
297
298
299
	buf_discard(buf);
}

/**
300
 * tipc_named_reinit - re-initialize local publication list
301
 *
Per Liden's avatar
Per Liden committed
302
303
304
305
306
307
 * 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.)
 */

308
void tipc_named_reinit(void)
Per Liden's avatar
Per Liden committed
309
310
311
{
	struct publication *publ;

312
	write_lock_bh(&tipc_nametbl_lock);
Per Liden's avatar
Per Liden committed
313
314
315
316
317
	list_for_each_entry(publ, &publ_root, local_list) {
		if (publ->node == tipc_own_addr)
			break;
		publ->node = tipc_own_addr;
	}
318
	write_unlock_bh(&tipc_nametbl_lock);
Per Liden's avatar
Per Liden committed
319
}