xref: /openbmc/linux/net/tipc/name_distr.c (revision afb46f79)
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 	struct tipc_link *l_ptr;
135 
136 	rcu_read_lock();
137 	list_for_each_entry_rcu(n_ptr, &tipc_node_list, list) {
138 		spin_lock_bh(&n_ptr->lock);
139 		l_ptr = n_ptr->active_links[n_ptr->addr & 1];
140 		if (l_ptr) {
141 			buf_copy = skb_copy(buf, GFP_ATOMIC);
142 			if (!buf_copy) {
143 				spin_unlock_bh(&n_ptr->lock);
144 				break;
145 			}
146 			msg_set_destnode(buf_msg(buf_copy), n_ptr->addr);
147 			__tipc_link_xmit(l_ptr, buf_copy);
148 		}
149 		spin_unlock_bh(&n_ptr->lock);
150 	}
151 	rcu_read_unlock();
152 
153 	kfree_skb(buf);
154 }
155 
156 /**
157  * tipc_named_publish - tell other nodes about a new publication by this node
158  */
159 void tipc_named_publish(struct publication *publ)
160 {
161 	struct sk_buff *buf;
162 	struct distr_item *item;
163 
164 	list_add_tail(&publ->local_list, &publ_lists[publ->scope]->list);
165 	publ_lists[publ->scope]->size++;
166 
167 	if (publ->scope == TIPC_NODE_SCOPE)
168 		return;
169 
170 	buf = named_prepare_buf(PUBLICATION, ITEM_SIZE, 0);
171 	if (!buf) {
172 		pr_warn("Publication distribution failure\n");
173 		return;
174 	}
175 
176 	item = (struct distr_item *)msg_data(buf_msg(buf));
177 	publ_to_item(item, publ);
178 	named_cluster_distribute(buf);
179 }
180 
181 /**
182  * tipc_named_withdraw - tell other nodes about a withdrawn publication by this node
183  */
184 void tipc_named_withdraw(struct publication *publ)
185 {
186 	struct sk_buff *buf;
187 	struct distr_item *item;
188 
189 	list_del(&publ->local_list);
190 	publ_lists[publ->scope]->size--;
191 
192 	if (publ->scope == TIPC_NODE_SCOPE)
193 		return;
194 
195 	buf = named_prepare_buf(WITHDRAWAL, ITEM_SIZE, 0);
196 	if (!buf) {
197 		pr_warn("Withdrawal distribution failure\n");
198 		return;
199 	}
200 
201 	item = (struct distr_item *)msg_data(buf_msg(buf));
202 	publ_to_item(item, publ);
203 	named_cluster_distribute(buf);
204 }
205 
206 /*
207  * named_distribute - prepare name info for bulk distribution to another node
208  */
209 static void named_distribute(struct list_head *message_list, u32 node,
210 			     struct publ_list *pls, u32 max_item_buf)
211 {
212 	struct publication *publ;
213 	struct sk_buff *buf = NULL;
214 	struct distr_item *item = NULL;
215 	u32 left = 0;
216 	u32 rest = pls->size * ITEM_SIZE;
217 
218 	list_for_each_entry(publ, &pls->list, local_list) {
219 		if (!buf) {
220 			left = (rest <= max_item_buf) ? rest : max_item_buf;
221 			rest -= left;
222 			buf = named_prepare_buf(PUBLICATION, left, node);
223 			if (!buf) {
224 				pr_warn("Bulk publication failure\n");
225 				return;
226 			}
227 			item = (struct distr_item *)msg_data(buf_msg(buf));
228 		}
229 		publ_to_item(item, publ);
230 		item++;
231 		left -= ITEM_SIZE;
232 		if (!left) {
233 			list_add_tail((struct list_head *)buf, message_list);
234 			buf = NULL;
235 		}
236 	}
237 }
238 
239 /**
240  * tipc_named_node_up - tell specified node about all publications by this node
241  */
242 void tipc_named_node_up(unsigned long nodearg)
243 {
244 	struct tipc_node *n_ptr;
245 	struct tipc_link *l_ptr;
246 	struct list_head message_list;
247 	u32 node = (u32)nodearg;
248 	u32 max_item_buf = 0;
249 
250 	/* compute maximum amount of publication data to send per message */
251 	read_lock_bh(&tipc_net_lock);
252 	n_ptr = tipc_node_find(node);
253 	if (n_ptr) {
254 		tipc_node_lock(n_ptr);
255 		l_ptr = n_ptr->active_links[0];
256 		if (l_ptr)
257 			max_item_buf = ((l_ptr->max_pkt - INT_H_SIZE) /
258 				ITEM_SIZE) * ITEM_SIZE;
259 		tipc_node_unlock(n_ptr);
260 	}
261 	read_unlock_bh(&tipc_net_lock);
262 	if (!max_item_buf)
263 		return;
264 
265 	/* create list of publication messages, then send them as a unit */
266 	INIT_LIST_HEAD(&message_list);
267 
268 	read_lock_bh(&tipc_nametbl_lock);
269 	named_distribute(&message_list, node, &publ_cluster, max_item_buf);
270 	named_distribute(&message_list, node, &publ_zone, max_item_buf);
271 	read_unlock_bh(&tipc_nametbl_lock);
272 
273 	tipc_link_names_xmit(&message_list, node);
274 }
275 
276 /**
277  * named_purge_publ - remove publication associated with a failed node
278  *
279  * Invoked for each publication issued by a newly failed node.
280  * Removes publication structure from name table & deletes it.
281  */
282 static void named_purge_publ(struct publication *publ)
283 {
284 	struct publication *p;
285 
286 	write_lock_bh(&tipc_nametbl_lock);
287 	p = tipc_nametbl_remove_publ(publ->type, publ->lower,
288 				     publ->node, publ->ref, publ->key);
289 	if (p)
290 		tipc_nodesub_unsubscribe(&p->subscr);
291 	write_unlock_bh(&tipc_nametbl_lock);
292 
293 	if (p != publ) {
294 		pr_err("Unable to remove publication from failed node\n"
295 		       " (type=%u, lower=%u, node=0x%x, ref=%u, key=%u)\n",
296 		       publ->type, publ->lower, publ->node, publ->ref,
297 		       publ->key);
298 	}
299 
300 	kfree(p);
301 }
302 
303 /**
304  * tipc_named_rcv - process name table update message sent by another node
305  */
306 void tipc_named_rcv(struct sk_buff *buf)
307 {
308 	struct publication *publ;
309 	struct tipc_msg *msg = buf_msg(buf);
310 	struct distr_item *item = (struct distr_item *)msg_data(msg);
311 	u32 count = msg_data_sz(msg) / ITEM_SIZE;
312 
313 	write_lock_bh(&tipc_nametbl_lock);
314 	while (count--) {
315 		if (msg_type(msg) == PUBLICATION) {
316 			publ = tipc_nametbl_insert_publ(ntohl(item->type),
317 							ntohl(item->lower),
318 							ntohl(item->upper),
319 							TIPC_CLUSTER_SCOPE,
320 							msg_orignode(msg),
321 							ntohl(item->ref),
322 							ntohl(item->key));
323 			if (publ) {
324 				tipc_nodesub_subscribe(&publ->subscr,
325 						       msg_orignode(msg),
326 						       publ,
327 						       (net_ev_handler)
328 						       named_purge_publ);
329 			}
330 		} else if (msg_type(msg) == WITHDRAWAL) {
331 			publ = tipc_nametbl_remove_publ(ntohl(item->type),
332 							ntohl(item->lower),
333 							msg_orignode(msg),
334 							ntohl(item->ref),
335 							ntohl(item->key));
336 
337 			if (publ) {
338 				tipc_nodesub_unsubscribe(&publ->subscr);
339 				kfree(publ);
340 			} else {
341 				pr_err("Unable to remove publication by node 0x%x\n"
342 				       " (type=%u, lower=%u, ref=%u, key=%u)\n",
343 				       msg_orignode(msg), ntohl(item->type),
344 				       ntohl(item->lower), ntohl(item->ref),
345 				       ntohl(item->key));
346 			}
347 		} else {
348 			pr_warn("Unrecognized name table message received\n");
349 		}
350 		item++;
351 	}
352 	write_unlock_bh(&tipc_nametbl_lock);
353 	kfree_skb(buf);
354 }
355 
356 /**
357  * tipc_named_reinit - re-initialize local publications
358  *
359  * This routine is called whenever TIPC networking is enabled.
360  * All name table entries published by this node are updated to reflect
361  * the node's new network address.
362  */
363 void tipc_named_reinit(void)
364 {
365 	struct publication *publ;
366 	int scope;
367 
368 	write_lock_bh(&tipc_nametbl_lock);
369 
370 	for (scope = TIPC_ZONE_SCOPE; scope <= TIPC_NODE_SCOPE; scope++)
371 		list_for_each_entry(publ, &publ_lists[scope]->list, local_list)
372 			publ->node = tipc_own_addr;
373 
374 	write_unlock_bh(&tipc_nametbl_lock);
375 }
376