1 /*
2 * net/tipc/name_distr.c: TIPC name distribution code
3 *
4 * Copyright (c) 2000-2006, Ericsson AB
5 * Copyright (c) 2005, 2010-2011, Wind River Systems
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
10 *
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.
19 *
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
34 * POSSIBILITY OF SUCH DAMAGE.
35 */
36
37 #include "core.h"
38 #include "link.h"
39 #include "name_distr.h"
40
41 #define ITEM_SIZE sizeof(struct distr_item)
42
43 /**
44 * struct distr_item - publication info distributed to other nodes
45 * @type: name sequence type
46 * @lower: name sequence lower bound
47 * @upper: name sequence upper bound
48 * @ref: publishing port reference
49 * @key: publication key
50 *
51 * ===> All fields are stored in network byte order. <===
52 *
53 * First 3 fields identify (name or) name sequence being published.
54 * Reference field uniquely identifies port that published name sequence.
55 * Key field uniquely identifies publication, in the event a port has
56 * multiple publications of the same name sequence.
57 *
58 * Note: There is no field that identifies the publishing node because it is
59 * the same for all items contained within a publication message.
60 */
61
62 struct distr_item {
63 __be32 type;
64 __be32 lower;
65 __be32 upper;
66 __be32 ref;
67 __be32 key;
68 };
69
70 /**
71 * List of externally visible publications by this node --
72 * that is, all publications having scope > TIPC_NODE_SCOPE.
73 */
74
75 static LIST_HEAD(publ_root);
76 static u32 publ_cnt;
77
78 /**
79 * publ_to_item - add publication info to a publication message
80 */
81
publ_to_item(struct distr_item * i,struct publication * p)82 static void publ_to_item(struct distr_item *i, struct publication *p)
83 {
84 i->type = htonl(p->type);
85 i->lower = htonl(p->lower);
86 i->upper = htonl(p->upper);
87 i->ref = htonl(p->ref);
88 i->key = htonl(p->key);
89 }
90
91 /**
92 * named_prepare_buf - allocate & initialize a publication message
93 */
94
named_prepare_buf(u32 type,u32 size,u32 dest)95 static struct sk_buff *named_prepare_buf(u32 type, u32 size, u32 dest)
96 {
97 struct sk_buff *buf = tipc_buf_acquire(INT_H_SIZE + size);
98 struct tipc_msg *msg;
99
100 if (buf != NULL) {
101 msg = buf_msg(buf);
102 tipc_msg_init(msg, NAME_DISTRIBUTOR, type, INT_H_SIZE, dest);
103 msg_set_size(msg, INT_H_SIZE + size);
104 }
105 return buf;
106 }
107
named_cluster_distribute(struct sk_buff * buf)108 static void named_cluster_distribute(struct sk_buff *buf)
109 {
110 struct sk_buff *buf_copy;
111 struct tipc_node *n_ptr;
112
113 list_for_each_entry(n_ptr, &tipc_node_list, list) {
114 if (tipc_node_active_links(n_ptr)) {
115 buf_copy = skb_copy(buf, GFP_ATOMIC);
116 if (!buf_copy)
117 break;
118 msg_set_destnode(buf_msg(buf_copy), n_ptr->addr);
119 tipc_link_send(buf_copy, n_ptr->addr, n_ptr->addr);
120 }
121 }
122
123 kfree_skb(buf);
124 }
125
126 /**
127 * tipc_named_publish - tell other nodes about a new publication by this node
128 */
129
tipc_named_publish(struct publication * publ)130 void tipc_named_publish(struct publication *publ)
131 {
132 struct sk_buff *buf;
133 struct distr_item *item;
134
135 list_add_tail(&publ->local_list, &publ_root);
136 publ_cnt++;
137
138 buf = named_prepare_buf(PUBLICATION, ITEM_SIZE, 0);
139 if (!buf) {
140 warn("Publication distribution failure\n");
141 return;
142 }
143
144 item = (struct distr_item *)msg_data(buf_msg(buf));
145 publ_to_item(item, publ);
146 named_cluster_distribute(buf);
147 }
148
149 /**
150 * tipc_named_withdraw - tell other nodes about a withdrawn publication by this node
151 */
152
tipc_named_withdraw(struct publication * publ)153 void tipc_named_withdraw(struct publication *publ)
154 {
155 struct sk_buff *buf;
156 struct distr_item *item;
157
158 list_del(&publ->local_list);
159 publ_cnt--;
160
161 buf = named_prepare_buf(WITHDRAWAL, ITEM_SIZE, 0);
162 if (!buf) {
163 warn("Withdrawal distribution failure\n");
164 return;
165 }
166
167 item = (struct distr_item *)msg_data(buf_msg(buf));
168 publ_to_item(item, publ);
169 named_cluster_distribute(buf);
170 }
171
172 /**
173 * tipc_named_node_up - tell specified node about all publications by this node
174 */
175
tipc_named_node_up(unsigned long nodearg)176 void tipc_named_node_up(unsigned long nodearg)
177 {
178 struct tipc_node *n_ptr;
179 struct tipc_link *l_ptr;
180 struct publication *publ;
181 struct distr_item *item = NULL;
182 struct sk_buff *buf = NULL;
183 struct list_head message_list;
184 u32 node = (u32)nodearg;
185 u32 left = 0;
186 u32 rest;
187 u32 max_item_buf = 0;
188
189 /* compute maximum amount of publication data to send per message */
190
191 read_lock_bh(&tipc_net_lock);
192 n_ptr = tipc_node_find(node);
193 if (n_ptr) {
194 tipc_node_lock(n_ptr);
195 l_ptr = n_ptr->active_links[0];
196 if (l_ptr)
197 max_item_buf = ((l_ptr->max_pkt - INT_H_SIZE) /
198 ITEM_SIZE) * ITEM_SIZE;
199 tipc_node_unlock(n_ptr);
200 }
201 read_unlock_bh(&tipc_net_lock);
202 if (!max_item_buf)
203 return;
204
205 /* create list of publication messages, then send them as a unit */
206
207 INIT_LIST_HEAD(&message_list);
208
209 read_lock_bh(&tipc_nametbl_lock);
210 rest = publ_cnt * ITEM_SIZE;
211
212 list_for_each_entry(publ, &publ_root, local_list) {
213 if (!buf) {
214 left = (rest <= max_item_buf) ? rest : max_item_buf;
215 rest -= left;
216 buf = named_prepare_buf(PUBLICATION, left, node);
217 if (!buf) {
218 warn("Bulk publication distribution failure\n");
219 goto exit;
220 }
221 item = (struct distr_item *)msg_data(buf_msg(buf));
222 }
223 publ_to_item(item, publ);
224 item++;
225 left -= ITEM_SIZE;
226 if (!left) {
227 list_add_tail((struct list_head *)buf, &message_list);
228 buf = NULL;
229 }
230 }
231 exit:
232 read_unlock_bh(&tipc_nametbl_lock);
233
234 tipc_link_send_names(&message_list, (u32)node);
235 }
236
237 /**
238 * named_purge_publ - remove publication associated with a failed node
239 *
240 * Invoked for each publication issued by a newly failed node.
241 * Removes publication structure from name table & deletes it.
242 */
243
named_purge_publ(struct publication * publ)244 static void named_purge_publ(struct publication *publ)
245 {
246 struct publication *p;
247
248 write_lock_bh(&tipc_nametbl_lock);
249 p = tipc_nametbl_remove_publ(publ->type, publ->lower,
250 publ->node, publ->ref, publ->key);
251 if (p)
252 tipc_nodesub_unsubscribe(&p->subscr);
253 write_unlock_bh(&tipc_nametbl_lock);
254
255 if (p != publ) {
256 err("Unable to remove publication from failed node\n"
257 "(type=%u, lower=%u, node=0x%x, ref=%u, key=%u)\n",
258 publ->type, publ->lower, publ->node, publ->ref, publ->key);
259 }
260
261 kfree(p);
262 }
263
264 /**
265 * tipc_named_recv - process name table update message sent by another node
266 */
267
tipc_named_recv(struct sk_buff * buf)268 void tipc_named_recv(struct sk_buff *buf)
269 {
270 struct publication *publ;
271 struct tipc_msg *msg = buf_msg(buf);
272 struct distr_item *item = (struct distr_item *)msg_data(msg);
273 u32 count = msg_data_sz(msg) / ITEM_SIZE;
274
275 write_lock_bh(&tipc_nametbl_lock);
276 while (count--) {
277 if (msg_type(msg) == PUBLICATION) {
278 publ = tipc_nametbl_insert_publ(ntohl(item->type),
279 ntohl(item->lower),
280 ntohl(item->upper),
281 TIPC_CLUSTER_SCOPE,
282 msg_orignode(msg),
283 ntohl(item->ref),
284 ntohl(item->key));
285 if (publ) {
286 tipc_nodesub_subscribe(&publ->subscr,
287 msg_orignode(msg),
288 publ,
289 (net_ev_handler)
290 named_purge_publ);
291 }
292 } else if (msg_type(msg) == WITHDRAWAL) {
293 publ = tipc_nametbl_remove_publ(ntohl(item->type),
294 ntohl(item->lower),
295 msg_orignode(msg),
296 ntohl(item->ref),
297 ntohl(item->key));
298
299 if (publ) {
300 tipc_nodesub_unsubscribe(&publ->subscr);
301 kfree(publ);
302 } else {
303 err("Unable to remove publication by node 0x%x\n"
304 "(type=%u, lower=%u, ref=%u, key=%u)\n",
305 msg_orignode(msg),
306 ntohl(item->type), ntohl(item->lower),
307 ntohl(item->ref), ntohl(item->key));
308 }
309 } else {
310 warn("Unrecognized name table message received\n");
311 }
312 item++;
313 }
314 write_unlock_bh(&tipc_nametbl_lock);
315 kfree_skb(buf);
316 }
317
318 /**
319 * tipc_named_reinit - re-initialize local publication list
320 *
321 * This routine is called whenever TIPC networking is enabled.
322 * All existing publications by this node that have "cluster" or "zone" scope
323 * are updated to reflect the node's new network address.
324 */
325
tipc_named_reinit(void)326 void tipc_named_reinit(void)
327 {
328 struct publication *publ;
329
330 write_lock_bh(&tipc_nametbl_lock);
331
332 list_for_each_entry(publ, &publ_root, local_list)
333 publ->node = tipc_own_addr;
334
335 write_unlock_bh(&tipc_nametbl_lock);
336 }
337