xref: /openbmc/linux/net/tipc/name_distr.c (revision 275876e2)
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 /**
42  * struct publ_list - list of publications made by this node
43  * @list: circular list of publications
44  * @list_size: number of entries in list
45  */
46 struct publ_list {
47 	struct list_head list;
48 	u32 size;
49 };
50 
51 static struct publ_list publ_zone = {
52 	.list = LIST_HEAD_INIT(publ_zone.list),
53 	.size = 0,
54 };
55 
56 static struct publ_list publ_cluster = {
57 	.list = LIST_HEAD_INIT(publ_cluster.list),
58 	.size = 0,
59 };
60 
61 static struct publ_list publ_node = {
62 	.list = LIST_HEAD_INIT(publ_node.list),
63 	.size = 0,
64 };
65 
66 static struct publ_list *publ_lists[] = {
67 	NULL,
68 	&publ_zone,	/* publ_lists[TIPC_ZONE_SCOPE]		*/
69 	&publ_cluster,	/* publ_lists[TIPC_CLUSTER_SCOPE]	*/
70 	&publ_node	/* publ_lists[TIPC_NODE_SCOPE]		*/
71 };
72 
73 
74 /**
75  * publ_to_item - add publication info to a publication message
76  */
77 static void publ_to_item(struct distr_item *i, struct publication *p)
78 {
79 	i->type = htonl(p->type);
80 	i->lower = htonl(p->lower);
81 	i->upper = htonl(p->upper);
82 	i->ref = htonl(p->ref);
83 	i->key = htonl(p->key);
84 }
85 
86 /**
87  * named_prepare_buf - allocate & initialize a publication message
88  */
89 static struct sk_buff *named_prepare_buf(u32 type, u32 size, u32 dest)
90 {
91 	struct sk_buff *buf = tipc_buf_acquire(INT_H_SIZE + size);
92 	struct tipc_msg *msg;
93 
94 	if (buf != NULL) {
95 		msg = buf_msg(buf);
96 		tipc_msg_init(msg, NAME_DISTRIBUTOR, type, INT_H_SIZE, dest);
97 		msg_set_size(msg, INT_H_SIZE + size);
98 	}
99 	return buf;
100 }
101 
102 void named_cluster_distribute(struct sk_buff *buf)
103 {
104 	struct sk_buff *obuf;
105 	struct tipc_node *node;
106 	u32 dnode;
107 
108 	rcu_read_lock();
109 	list_for_each_entry_rcu(node, &tipc_node_list, list) {
110 		dnode = node->addr;
111 		if (in_own_node(dnode))
112 			continue;
113 		if (!tipc_node_active_links(node))
114 			continue;
115 		obuf = skb_copy(buf, GFP_ATOMIC);
116 		if (!obuf)
117 			break;
118 		msg_set_destnode(buf_msg(obuf), dnode);
119 		tipc_link_xmit(obuf, dnode, dnode);
120 	}
121 	rcu_read_unlock();
122 
123 	kfree_skb(buf);
124 }
125 
126 /**
127  * tipc_named_publish - tell other nodes about a new publication by this node
128  */
129 struct sk_buff *tipc_named_publish(struct publication *publ)
130 {
131 	struct sk_buff *buf;
132 	struct distr_item *item;
133 
134 	list_add_tail(&publ->local_list, &publ_lists[publ->scope]->list);
135 	publ_lists[publ->scope]->size++;
136 
137 	if (publ->scope == TIPC_NODE_SCOPE)
138 		return NULL;
139 
140 	buf = named_prepare_buf(PUBLICATION, ITEM_SIZE, 0);
141 	if (!buf) {
142 		pr_warn("Publication distribution failure\n");
143 		return NULL;
144 	}
145 
146 	item = (struct distr_item *)msg_data(buf_msg(buf));
147 	publ_to_item(item, publ);
148 	return buf;
149 }
150 
151 /**
152  * tipc_named_withdraw - tell other nodes about a withdrawn publication by this node
153  */
154 struct sk_buff *tipc_named_withdraw(struct publication *publ)
155 {
156 	struct sk_buff *buf;
157 	struct distr_item *item;
158 
159 	list_del(&publ->local_list);
160 	publ_lists[publ->scope]->size--;
161 
162 	if (publ->scope == TIPC_NODE_SCOPE)
163 		return NULL;
164 
165 	buf = named_prepare_buf(WITHDRAWAL, ITEM_SIZE, 0);
166 	if (!buf) {
167 		pr_warn("Withdrawal distribution failure\n");
168 		return NULL;
169 	}
170 
171 	item = (struct distr_item *)msg_data(buf_msg(buf));
172 	publ_to_item(item, publ);
173 	return buf;
174 }
175 
176 /**
177  * named_distribute - prepare name info for bulk distribution to another node
178  * @msg_list: list of messages (buffers) to be returned from this function
179  * @dnode: node to be updated
180  * @pls: linked list of publication items to be packed into buffer chain
181  */
182 static void named_distribute(struct list_head *msg_list, u32 dnode,
183 			     struct publ_list *pls)
184 {
185 	struct publication *publ;
186 	struct sk_buff *buf = NULL;
187 	struct distr_item *item = NULL;
188 	uint dsz = pls->size * ITEM_SIZE;
189 	uint msg_dsz = (tipc_node_get_mtu(dnode, 0) / ITEM_SIZE) * ITEM_SIZE;
190 	uint rem = dsz;
191 	uint msg_rem = 0;
192 
193 	list_for_each_entry(publ, &pls->list, local_list) {
194 		/* Prepare next buffer: */
195 		if (!buf) {
196 			msg_rem = min_t(uint, rem, msg_dsz);
197 			rem -= msg_rem;
198 			buf = named_prepare_buf(PUBLICATION, msg_rem, dnode);
199 			if (!buf) {
200 				pr_warn("Bulk publication failure\n");
201 				return;
202 			}
203 			item = (struct distr_item *)msg_data(buf_msg(buf));
204 		}
205 
206 		/* Pack publication into message: */
207 		publ_to_item(item, publ);
208 		item++;
209 		msg_rem -= ITEM_SIZE;
210 
211 		/* Append full buffer to list: */
212 		if (!msg_rem) {
213 			list_add_tail((struct list_head *)buf, msg_list);
214 			buf = NULL;
215 		}
216 	}
217 }
218 
219 /**
220  * tipc_named_node_up - tell specified node about all publications by this node
221  */
222 void tipc_named_node_up(u32 dnode)
223 {
224 	LIST_HEAD(msg_list);
225 	struct sk_buff *buf_chain;
226 
227 	read_lock_bh(&tipc_nametbl_lock);
228 	named_distribute(&msg_list, dnode, &publ_cluster);
229 	named_distribute(&msg_list, dnode, &publ_zone);
230 	read_unlock_bh(&tipc_nametbl_lock);
231 
232 	/* Convert circular list to linear list and send: */
233 	buf_chain = (struct sk_buff *)msg_list.next;
234 	((struct sk_buff *)msg_list.prev)->next = NULL;
235 	tipc_link_xmit(buf_chain, dnode, dnode);
236 }
237 
238 /**
239  * named_purge_publ - remove publication associated with a failed node
240  *
241  * Invoked for each publication issued by a newly failed node.
242  * Removes publication structure from name table & deletes it.
243  */
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 		pr_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,
259 		       publ->key);
260 	}
261 
262 	kfree(p);
263 }
264 
265 /**
266  * tipc_named_rcv - process name table update message sent by another node
267  */
268 void tipc_named_rcv(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 				pr_err("Unable to remove publication by node 0x%x\n"
304 				       " (type=%u, lower=%u, ref=%u, key=%u)\n",
305 				       msg_orignode(msg), ntohl(item->type),
306 				       ntohl(item->lower), ntohl(item->ref),
307 				       ntohl(item->key));
308 			}
309 		} else {
310 			pr_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 publications
320  *
321  * This routine is called whenever TIPC networking is enabled.
322  * All name table entries published by this node are updated to reflect
323  * the node's new network address.
324  */
325 void tipc_named_reinit(void)
326 {
327 	struct publication *publ;
328 	int scope;
329 
330 	write_lock_bh(&tipc_nametbl_lock);
331 
332 	for (scope = TIPC_ZONE_SCOPE; scope <= TIPC_NODE_SCOPE; scope++)
333 		list_for_each_entry(publ, &publ_lists[scope]->list, local_list)
334 			publ->node = tipc_own_addr;
335 
336 	write_unlock_bh(&tipc_nametbl_lock);
337 }
338