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Per Lidenb97bf3f2006-01-02 19:04:38 +01001/*
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 *
Per Liden9ea1fd32006-01-11 13:30:43 +01009 * Redistribution and use in source and binary forms, with or without
Per Lidenb97bf3f2006-01-02 19:04:38 +010010 * modification, are permitted provided that the following conditions are met:
11 *
Per Liden9ea1fd32006-01-11 13:30:43 +010012 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. Neither the names of the copyright holders nor the names of its
18 * contributors may be used to endorse or promote products derived from
19 * this software without specific prior written permission.
Per Lidenb97bf3f2006-01-02 19:04:38 +010020 *
Per Liden9ea1fd32006-01-11 13:30:43 +010021 * Alternatively, this software may be distributed under the terms of the
22 * GNU General Public License ("GPL") version 2 as published by the Free
23 * Software Foundation.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
26 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
29 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
Per Lidenb97bf3f2006-01-02 19:04:38 +010035 * POSSIBILITY OF SUCH DAMAGE.
36 */
37
38#include "core.h"
39#include "cluster.h"
40#include "dbg.h"
41#include "link.h"
42#include "msg.h"
43#include "name_distr.h"
44
45#undef DBG_OUTPUT
46#define DBG_OUTPUT NULL
47
48#define ITEM_SIZE sizeof(struct distr_item)
49
50/**
51 * struct distr_item - publication info distributed to other nodes
52 * @type: name sequence type
53 * @lower: name sequence lower bound
54 * @upper: name sequence upper bound
55 * @ref: publishing port reference
56 * @key: publication key
57 *
58 * ===> All fields are stored in network byte order. <===
59 *
60 * First 3 fields identify (name or) name sequence being published.
61 * Reference field uniquely identifies port that published name sequence.
62 * Key field uniquely identifies publication, in the event a port has
63 * multiple publications of the same name sequence.
64 *
65 * Note: There is no field that identifies the publishing node because it is
66 * the same for all items contained within a publication message.
67 */
68
69struct distr_item {
70 u32 type;
71 u32 lower;
72 u32 upper;
73 u32 ref;
74 u32 key;
75};
76
77/**
78 * List of externally visible publications by this node --
79 * that is, all publications having scope > TIPC_NODE_SCOPE.
80 */
81
82static LIST_HEAD(publ_root);
83static u32 publ_cnt = 0;
84
85/**
86 * publ_to_item - add publication info to a publication message
87 */
88
89static void publ_to_item(struct distr_item *i, struct publication *p)
90{
91 i->type = htonl(p->type);
92 i->lower = htonl(p->lower);
93 i->upper = htonl(p->upper);
94 i->ref = htonl(p->ref);
95 i->key = htonl(p->key);
96 dbg("publ_to_item: %u, %u, %u\n", p->type, p->lower, p->upper);
97}
98
99/**
100 * named_prepare_buf - allocate & initialize a publication message
101 */
102
103static struct sk_buff *named_prepare_buf(u32 type, u32 size, u32 dest)
104{
105 struct sk_buff *buf = buf_acquire(LONG_H_SIZE + size);
106 struct tipc_msg *msg;
107
108 if (buf != NULL) {
109 msg = buf_msg(buf);
110 msg_init(msg, NAME_DISTRIBUTOR, type, TIPC_OK,
111 LONG_H_SIZE, dest);
112 msg_set_size(msg, LONG_H_SIZE + size);
113 }
114 return buf;
115}
116
117/**
118 * named_publish - tell other nodes about a new publication by this node
119 */
120
121void named_publish(struct publication *publ)
122{
123 struct sk_buff *buf;
124 struct distr_item *item;
125
126 list_add(&publ->local_list, &publ_root);
127 publ_cnt++;
128
129 buf = named_prepare_buf(PUBLICATION, ITEM_SIZE, 0);
130 if (!buf) {
131 warn("Memory squeeze; failed to distribute publication\n");
132 return;
133 }
134
135 item = (struct distr_item *)msg_data(buf_msg(buf));
136 publ_to_item(item, publ);
137 dbg("named_withdraw: broadcasting publish msg\n");
138 cluster_broadcast(buf);
139}
140
141/**
142 * named_withdraw - tell other nodes about a withdrawn publication by this node
143 */
144
145void named_withdraw(struct publication *publ)
146{
147 struct sk_buff *buf;
148 struct distr_item *item;
149
150 list_del(&publ->local_list);
151 publ_cnt--;
152
153 buf = named_prepare_buf(WITHDRAWAL, ITEM_SIZE, 0);
154 if (!buf) {
155 warn("Memory squeeze; failed to distribute withdrawal\n");
156 return;
157 }
158
159 item = (struct distr_item *)msg_data(buf_msg(buf));
160 publ_to_item(item, publ);
161 dbg("named_withdraw: broadcasting withdraw msg\n");
162 cluster_broadcast(buf);
163}
164
165/**
166 * named_node_up - tell specified node about all publications by this node
167 */
168
169void named_node_up(unsigned long node)
170{
171 struct publication *publ;
172 struct distr_item *item = 0;
173 struct sk_buff *buf = 0;
174 u32 left = 0;
175 u32 rest;
176 u32 max_item_buf;
177
178 assert(in_own_cluster(node));
179 read_lock_bh(&nametbl_lock);
180 max_item_buf = TIPC_MAX_USER_MSG_SIZE / ITEM_SIZE;
181 max_item_buf *= ITEM_SIZE;
182 rest = publ_cnt * ITEM_SIZE;
183
184 list_for_each_entry(publ, &publ_root, local_list) {
185 if (!buf) {
186 left = (rest <= max_item_buf) ? rest : max_item_buf;
187 rest -= left;
188 buf = named_prepare_buf(PUBLICATION, left, node);
189 if (buf == NULL) {
190 warn("Memory Squeeze; could not send publication\n");
191 goto exit;
192 }
193 item = (struct distr_item *)msg_data(buf_msg(buf));
194 }
195 publ_to_item(item, publ);
196 item++;
197 left -= ITEM_SIZE;
198 if (!left) {
199 msg_set_link_selector(buf_msg(buf), node);
200 dbg("named_node_up: sending publish msg to "
201 "<%u.%u.%u>\n", tipc_zone(node),
202 tipc_cluster(node), tipc_node(node));
203 link_send(buf, node, node);
204 buf = 0;
205 }
206 }
207exit:
208 read_unlock_bh(&nametbl_lock);
209}
210
211/**
212 * node_is_down - remove publication associated with a failed node
213 *
214 * Invoked for each publication issued by a newly failed node.
215 * Removes publication structure from name table & deletes it.
216 * In rare cases the link may have come back up again when this
217 * function is called, and we have two items representing the same
218 * publication. Nudge this item's key to distinguish it from the other.
219 * (Note: Publication's node subscription is already unsubscribed.)
220 */
221
222static void node_is_down(struct publication *publ)
223{
224 struct publication *p;
225 write_lock_bh(&nametbl_lock);
226 dbg("node_is_down: withdrawing %u, %u, %u\n",
227 publ->type, publ->lower, publ->upper);
228 publ->key += 1222345;
229 p = nametbl_remove_publ(publ->type, publ->lower,
230 publ->node, publ->ref, publ->key);
231 assert(p == publ);
232 write_unlock_bh(&nametbl_lock);
233 if (publ)
234 kfree(publ);
235}
236
237/**
238 * named_recv - process name table update message sent by another node
239 */
240
241void named_recv(struct sk_buff *buf)
242{
243 struct publication *publ;
244 struct tipc_msg *msg = buf_msg(buf);
245 struct distr_item *item = (struct distr_item *)msg_data(msg);
246 u32 count = msg_data_sz(msg) / ITEM_SIZE;
247
248 write_lock_bh(&nametbl_lock);
249 while (count--) {
250 if (msg_type(msg) == PUBLICATION) {
251 dbg("named_recv: got publication for %u, %u, %u\n",
252 ntohl(item->type), ntohl(item->lower),
253 ntohl(item->upper));
254 publ = nametbl_insert_publ(ntohl(item->type),
255 ntohl(item->lower),
256 ntohl(item->upper),
257 TIPC_CLUSTER_SCOPE,
258 msg_orignode(msg),
259 ntohl(item->ref),
260 ntohl(item->key));
261 if (publ) {
262 nodesub_subscribe(&publ->subscr,
263 msg_orignode(msg),
264 publ,
265 (net_ev_handler)node_is_down);
266 }
267 } else if (msg_type(msg) == WITHDRAWAL) {
268 dbg("named_recv: got withdrawl for %u, %u, %u\n",
269 ntohl(item->type), ntohl(item->lower),
270 ntohl(item->upper));
271 publ = nametbl_remove_publ(ntohl(item->type),
272 ntohl(item->lower),
273 msg_orignode(msg),
274 ntohl(item->ref),
275 ntohl(item->key));
276
277 if (publ) {
278 nodesub_unsubscribe(&publ->subscr);
279 kfree(publ);
280 }
281 } else {
282 warn("named_recv: unknown msg\n");
283 }
284 item++;
285 }
286 write_unlock_bh(&nametbl_lock);
287 buf_discard(buf);
288}
289
290/**
291 * named_reinit - re-initialize local publication list
292 *
293 * This routine is called whenever TIPC networking is (re)enabled.
294 * All existing publications by this node that have "cluster" or "zone" scope
295 * are updated to reflect the node's current network address.
296 * (If the node's address is unchanged, the update loop terminates immediately.)
297 */
298
299void named_reinit(void)
300{
301 struct publication *publ;
302
303 write_lock_bh(&nametbl_lock);
304 list_for_each_entry(publ, &publ_root, local_list) {
305 if (publ->node == tipc_own_addr)
306 break;
307 publ->node = tipc_own_addr;
308 }
309 write_unlock_bh(&nametbl_lock);
310}