xref: /openbmc/linux/net/tipc/name_distr.c (revision 54cbac81)
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 struct distr_item {
62 	__be32 type;
63 	__be32 lower;
64 	__be32 upper;
65 	__be32 ref;
66 	__be32 key;
67 };
68 
69 /**
70  * struct publ_list - list of publications made by this node
71  * @list: circular list of publications
72  * @list_size: number of entries in list
73  */
74 struct publ_list {
75 	struct list_head list;
76 	u32 size;
77 };
78 
79 static struct publ_list publ_zone = {
80 	.list = LIST_HEAD_INIT(publ_zone.list),
81 	.size = 0,
82 };
83 
84 static struct publ_list publ_cluster = {
85 	.list = LIST_HEAD_INIT(publ_cluster.list),
86 	.size = 0,
87 };
88 
89 static struct publ_list publ_node = {
90 	.list = LIST_HEAD_INIT(publ_node.list),
91 	.size = 0,
92 };
93 
94 static struct publ_list *publ_lists[] = {
95 	NULL,
96 	&publ_zone,	/* publ_lists[TIPC_ZONE_SCOPE]		*/
97 	&publ_cluster,	/* publ_lists[TIPC_CLUSTER_SCOPE]	*/
98 	&publ_node	/* publ_lists[TIPC_NODE_SCOPE]		*/
99 };
100 
101 
102 /**
103  * publ_to_item - add publication info to a publication message
104  */
105 static void publ_to_item(struct distr_item *i, struct publication *p)
106 {
107 	i->type = htonl(p->type);
108 	i->lower = htonl(p->lower);
109 	i->upper = htonl(p->upper);
110 	i->ref = htonl(p->ref);
111 	i->key = htonl(p->key);
112 }
113 
114 /**
115  * named_prepare_buf - allocate & initialize a publication message
116  */
117 static struct sk_buff *named_prepare_buf(u32 type, u32 size, u32 dest)
118 {
119 	struct sk_buff *buf = tipc_buf_acquire(INT_H_SIZE + size);
120 	struct tipc_msg *msg;
121 
122 	if (buf != NULL) {
123 		msg = buf_msg(buf);
124 		tipc_msg_init(msg, NAME_DISTRIBUTOR, type, INT_H_SIZE, dest);
125 		msg_set_size(msg, INT_H_SIZE + size);
126 	}
127 	return buf;
128 }
129 
130 static void named_cluster_distribute(struct sk_buff *buf)
131 {
132 	struct sk_buff *buf_copy;
133 	struct tipc_node *n_ptr;
134 
135 	list_for_each_entry(n_ptr, &tipc_node_list, list) {
136 		if (tipc_node_active_links(n_ptr)) {
137 			buf_copy = skb_copy(buf, GFP_ATOMIC);
138 			if (!buf_copy)
139 				break;
140 			msg_set_destnode(buf_msg(buf_copy), n_ptr->addr);
141 			tipc_link_send(buf_copy, n_ptr->addr, n_ptr->addr);
142 		}
143 	}
144 
145 	kfree_skb(buf);
146 }
147 
148 /**
149  * tipc_named_publish - tell other nodes about a new publication by this node
150  */
151 void tipc_named_publish(struct publication *publ)
152 {
153 	struct sk_buff *buf;
154 	struct distr_item *item;
155 
156 	list_add_tail(&publ->local_list, &publ_lists[publ->scope]->list);
157 	publ_lists[publ->scope]->size++;
158 
159 	if (publ->scope == TIPC_NODE_SCOPE)
160 		return;
161 
162 	buf = named_prepare_buf(PUBLICATION, ITEM_SIZE, 0);
163 	if (!buf) {
164 		pr_warn("Publication distribution failure\n");
165 		return;
166 	}
167 
168 	item = (struct distr_item *)msg_data(buf_msg(buf));
169 	publ_to_item(item, publ);
170 	named_cluster_distribute(buf);
171 }
172 
173 /**
174  * tipc_named_withdraw - tell other nodes about a withdrawn publication by this node
175  */
176 void tipc_named_withdraw(struct publication *publ)
177 {
178 	struct sk_buff *buf;
179 	struct distr_item *item;
180 
181 	list_del(&publ->local_list);
182 	publ_lists[publ->scope]->size--;
183 
184 	if (publ->scope == TIPC_NODE_SCOPE)
185 		return;
186 
187 	buf = named_prepare_buf(WITHDRAWAL, ITEM_SIZE, 0);
188 	if (!buf) {
189 		pr_warn("Withdrawal distribution failure\n");
190 		return;
191 	}
192 
193 	item = (struct distr_item *)msg_data(buf_msg(buf));
194 	publ_to_item(item, publ);
195 	named_cluster_distribute(buf);
196 }
197 
198 /*
199  * named_distribute - prepare name info for bulk distribution to another node
200  */
201 static void named_distribute(struct list_head *message_list, u32 node,
202 			     struct publ_list *pls, u32 max_item_buf)
203 {
204 	struct publication *publ;
205 	struct sk_buff *buf = NULL;
206 	struct distr_item *item = NULL;
207 	u32 left = 0;
208 	u32 rest = pls->size * ITEM_SIZE;
209 
210 	list_for_each_entry(publ, &pls->list, local_list) {
211 		if (!buf) {
212 			left = (rest <= max_item_buf) ? rest : max_item_buf;
213 			rest -= left;
214 			buf = named_prepare_buf(PUBLICATION, left, node);
215 			if (!buf) {
216 				pr_warn("Bulk publication failure\n");
217 				return;
218 			}
219 			item = (struct distr_item *)msg_data(buf_msg(buf));
220 		}
221 		publ_to_item(item, publ);
222 		item++;
223 		left -= ITEM_SIZE;
224 		if (!left) {
225 			list_add_tail((struct list_head *)buf, message_list);
226 			buf = NULL;
227 		}
228 	}
229 }
230 
231 /**
232  * tipc_named_node_up - tell specified node about all publications by this node
233  */
234 void tipc_named_node_up(unsigned long nodearg)
235 {
236 	struct tipc_node *n_ptr;
237 	struct tipc_link *l_ptr;
238 	struct list_head message_list;
239 	u32 node = (u32)nodearg;
240 	u32 max_item_buf = 0;
241 
242 	/* compute maximum amount of publication data to send per message */
243 	read_lock_bh(&tipc_net_lock);
244 	n_ptr = tipc_node_find(node);
245 	if (n_ptr) {
246 		tipc_node_lock(n_ptr);
247 		l_ptr = n_ptr->active_links[0];
248 		if (l_ptr)
249 			max_item_buf = ((l_ptr->max_pkt - INT_H_SIZE) /
250 				ITEM_SIZE) * ITEM_SIZE;
251 		tipc_node_unlock(n_ptr);
252 	}
253 	read_unlock_bh(&tipc_net_lock);
254 	if (!max_item_buf)
255 		return;
256 
257 	/* create list of publication messages, then send them as a unit */
258 	INIT_LIST_HEAD(&message_list);
259 
260 	read_lock_bh(&tipc_nametbl_lock);
261 	named_distribute(&message_list, node, &publ_cluster, max_item_buf);
262 	named_distribute(&message_list, node, &publ_zone, max_item_buf);
263 	read_unlock_bh(&tipc_nametbl_lock);
264 
265 	tipc_link_send_names(&message_list, node);
266 }
267 
268 /**
269  * named_purge_publ - remove publication associated with a failed node
270  *
271  * Invoked for each publication issued by a newly failed node.
272  * Removes publication structure from name table & deletes it.
273  */
274 static void named_purge_publ(struct publication *publ)
275 {
276 	struct publication *p;
277 
278 	write_lock_bh(&tipc_nametbl_lock);
279 	p = tipc_nametbl_remove_publ(publ->type, publ->lower,
280 				     publ->node, publ->ref, publ->key);
281 	if (p)
282 		tipc_nodesub_unsubscribe(&p->subscr);
283 	write_unlock_bh(&tipc_nametbl_lock);
284 
285 	if (p != publ) {
286 		pr_err("Unable to remove publication from failed node\n"
287 		       " (type=%u, lower=%u, node=0x%x, ref=%u, key=%u)\n",
288 		       publ->type, publ->lower, publ->node, publ->ref,
289 		       publ->key);
290 	}
291 
292 	kfree(p);
293 }
294 
295 /**
296  * tipc_named_recv - process name table update message sent by another node
297  */
298 void tipc_named_recv(struct sk_buff *buf)
299 {
300 	struct publication *publ;
301 	struct tipc_msg *msg = buf_msg(buf);
302 	struct distr_item *item = (struct distr_item *)msg_data(msg);
303 	u32 count = msg_data_sz(msg) / ITEM_SIZE;
304 
305 	write_lock_bh(&tipc_nametbl_lock);
306 	while (count--) {
307 		if (msg_type(msg) == PUBLICATION) {
308 			publ = tipc_nametbl_insert_publ(ntohl(item->type),
309 							ntohl(item->lower),
310 							ntohl(item->upper),
311 							TIPC_CLUSTER_SCOPE,
312 							msg_orignode(msg),
313 							ntohl(item->ref),
314 							ntohl(item->key));
315 			if (publ) {
316 				tipc_nodesub_subscribe(&publ->subscr,
317 						       msg_orignode(msg),
318 						       publ,
319 						       (net_ev_handler)
320 						       named_purge_publ);
321 			}
322 		} else if (msg_type(msg) == WITHDRAWAL) {
323 			publ = tipc_nametbl_remove_publ(ntohl(item->type),
324 							ntohl(item->lower),
325 							msg_orignode(msg),
326 							ntohl(item->ref),
327 							ntohl(item->key));
328 
329 			if (publ) {
330 				tipc_nodesub_unsubscribe(&publ->subscr);
331 				kfree(publ);
332 			} else {
333 				pr_err("Unable to remove publication by node 0x%x\n"
334 				       " (type=%u, lower=%u, ref=%u, key=%u)\n",
335 				       msg_orignode(msg), ntohl(item->type),
336 				       ntohl(item->lower), ntohl(item->ref),
337 				       ntohl(item->key));
338 			}
339 		} else {
340 			pr_warn("Unrecognized name table message received\n");
341 		}
342 		item++;
343 	}
344 	write_unlock_bh(&tipc_nametbl_lock);
345 	kfree_skb(buf);
346 }
347 
348 /**
349  * tipc_named_reinit - re-initialize local publications
350  *
351  * This routine is called whenever TIPC networking is enabled.
352  * All name table entries published by this node are updated to reflect
353  * the node's new network address.
354  */
355 void tipc_named_reinit(void)
356 {
357 	struct publication *publ;
358 	int scope;
359 
360 	write_lock_bh(&tipc_nametbl_lock);
361 
362 	for (scope = TIPC_ZONE_SCOPE; scope <= TIPC_NODE_SCOPE; scope++)
363 		list_for_each_entry(publ, &publ_lists[scope]->list, local_list)
364 			publ->node = tipc_own_addr;
365 
366 	write_unlock_bh(&tipc_nametbl_lock);
367 }
368