xref: /openbmc/linux/net/tipc/name_distr.c (revision 82003e04)
1 /*
2  * net/tipc/name_distr.c: TIPC name distribution code
3  *
4  * Copyright (c) 2000-2006, 2014, 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 int sysctl_tipc_named_timeout __read_mostly = 2000;
42 
43 struct distr_queue_item {
44 	struct distr_item i;
45 	u32 dtype;
46 	u32 node;
47 	unsigned long expires;
48 	struct list_head next;
49 };
50 
51 /**
52  * publ_to_item - add publication info to a publication message
53  */
54 static void publ_to_item(struct distr_item *i, struct publication *p)
55 {
56 	i->type = htonl(p->type);
57 	i->lower = htonl(p->lower);
58 	i->upper = htonl(p->upper);
59 	i->ref = htonl(p->ref);
60 	i->key = htonl(p->key);
61 }
62 
63 /**
64  * named_prepare_buf - allocate & initialize a publication message
65  *
66  * The buffer returned is of size INT_H_SIZE + payload size
67  */
68 static struct sk_buff *named_prepare_buf(struct net *net, u32 type, u32 size,
69 					 u32 dest)
70 {
71 	struct tipc_net *tn = net_generic(net, tipc_net_id);
72 	struct sk_buff *buf = tipc_buf_acquire(INT_H_SIZE + size);
73 	struct tipc_msg *msg;
74 
75 	if (buf != NULL) {
76 		msg = buf_msg(buf);
77 		tipc_msg_init(tn->own_addr, msg, NAME_DISTRIBUTOR, type,
78 			      INT_H_SIZE, dest);
79 		msg_set_size(msg, INT_H_SIZE + size);
80 	}
81 	return buf;
82 }
83 
84 /**
85  * tipc_named_publish - tell other nodes about a new publication by this node
86  */
87 struct sk_buff *tipc_named_publish(struct net *net, struct publication *publ)
88 {
89 	struct tipc_net *tn = net_generic(net, tipc_net_id);
90 	struct sk_buff *buf;
91 	struct distr_item *item;
92 
93 	list_add_tail_rcu(&publ->local_list,
94 			  &tn->nametbl->publ_list[publ->scope]);
95 
96 	if (publ->scope == TIPC_NODE_SCOPE)
97 		return NULL;
98 
99 	buf = named_prepare_buf(net, PUBLICATION, ITEM_SIZE, 0);
100 	if (!buf) {
101 		pr_warn("Publication distribution failure\n");
102 		return NULL;
103 	}
104 
105 	item = (struct distr_item *)msg_data(buf_msg(buf));
106 	publ_to_item(item, publ);
107 	return buf;
108 }
109 
110 /**
111  * tipc_named_withdraw - tell other nodes about a withdrawn publication by this node
112  */
113 struct sk_buff *tipc_named_withdraw(struct net *net, struct publication *publ)
114 {
115 	struct sk_buff *buf;
116 	struct distr_item *item;
117 
118 	list_del(&publ->local_list);
119 
120 	if (publ->scope == TIPC_NODE_SCOPE)
121 		return NULL;
122 
123 	buf = named_prepare_buf(net, WITHDRAWAL, ITEM_SIZE, 0);
124 	if (!buf) {
125 		pr_warn("Withdrawal distribution failure\n");
126 		return NULL;
127 	}
128 
129 	item = (struct distr_item *)msg_data(buf_msg(buf));
130 	publ_to_item(item, publ);
131 	return buf;
132 }
133 
134 /**
135  * named_distribute - prepare name info for bulk distribution to another node
136  * @list: list of messages (buffers) to be returned from this function
137  * @dnode: node to be updated
138  * @pls: linked list of publication items to be packed into buffer chain
139  */
140 static void named_distribute(struct net *net, struct sk_buff_head *list,
141 			     u32 dnode, struct list_head *pls)
142 {
143 	struct publication *publ;
144 	struct sk_buff *skb = NULL;
145 	struct distr_item *item = NULL;
146 	u32 msg_dsz = ((tipc_node_get_mtu(net, dnode, 0) - INT_H_SIZE) /
147 			ITEM_SIZE) * ITEM_SIZE;
148 	u32 msg_rem = msg_dsz;
149 
150 	list_for_each_entry(publ, pls, local_list) {
151 		/* Prepare next buffer: */
152 		if (!skb) {
153 			skb = named_prepare_buf(net, PUBLICATION, msg_rem,
154 						dnode);
155 			if (!skb) {
156 				pr_warn("Bulk publication failure\n");
157 				return;
158 			}
159 			msg_set_bc_ack_invalid(buf_msg(skb), true);
160 			item = (struct distr_item *)msg_data(buf_msg(skb));
161 		}
162 
163 		/* Pack publication into message: */
164 		publ_to_item(item, publ);
165 		item++;
166 		msg_rem -= ITEM_SIZE;
167 
168 		/* Append full buffer to list: */
169 		if (!msg_rem) {
170 			__skb_queue_tail(list, skb);
171 			skb = NULL;
172 			msg_rem = msg_dsz;
173 		}
174 	}
175 	if (skb) {
176 		msg_set_size(buf_msg(skb), INT_H_SIZE + (msg_dsz - msg_rem));
177 		skb_trim(skb, INT_H_SIZE + (msg_dsz - msg_rem));
178 		__skb_queue_tail(list, skb);
179 	}
180 }
181 
182 /**
183  * tipc_named_node_up - tell specified node about all publications by this node
184  */
185 void tipc_named_node_up(struct net *net, u32 dnode)
186 {
187 	struct tipc_net *tn = net_generic(net, tipc_net_id);
188 	struct sk_buff_head head;
189 
190 	__skb_queue_head_init(&head);
191 
192 	rcu_read_lock();
193 	named_distribute(net, &head, dnode,
194 			 &tn->nametbl->publ_list[TIPC_CLUSTER_SCOPE]);
195 	named_distribute(net, &head, dnode,
196 			 &tn->nametbl->publ_list[TIPC_ZONE_SCOPE]);
197 	rcu_read_unlock();
198 
199 	tipc_node_xmit(net, &head, dnode, 0);
200 }
201 
202 /**
203  * tipc_publ_purge - remove publication associated with a failed node
204  *
205  * Invoked for each publication issued by a newly failed node.
206  * Removes publication structure from name table & deletes it.
207  */
208 static void tipc_publ_purge(struct net *net, struct publication *publ, u32 addr)
209 {
210 	struct tipc_net *tn = net_generic(net, tipc_net_id);
211 	struct publication *p;
212 
213 	spin_lock_bh(&tn->nametbl_lock);
214 	p = tipc_nametbl_remove_publ(net, publ->type, publ->lower,
215 				     publ->node, publ->ref, publ->key);
216 	if (p)
217 		tipc_node_unsubscribe(net, &p->nodesub_list, addr);
218 	spin_unlock_bh(&tn->nametbl_lock);
219 
220 	if (p != publ) {
221 		pr_err("Unable to remove publication from failed node\n"
222 		       " (type=%u, lower=%u, node=0x%x, ref=%u, key=%u)\n",
223 		       publ->type, publ->lower, publ->node, publ->ref,
224 		       publ->key);
225 	}
226 
227 	kfree_rcu(p, rcu);
228 }
229 
230 /**
231  * tipc_dist_queue_purge - remove deferred updates from a node that went down
232  */
233 static void tipc_dist_queue_purge(struct net *net, u32 addr)
234 {
235 	struct tipc_net *tn = net_generic(net, tipc_net_id);
236 	struct distr_queue_item *e, *tmp;
237 
238 	spin_lock_bh(&tn->nametbl_lock);
239 	list_for_each_entry_safe(e, tmp, &tn->dist_queue, next) {
240 		if (e->node != addr)
241 			continue;
242 		list_del(&e->next);
243 		kfree(e);
244 	}
245 	spin_unlock_bh(&tn->nametbl_lock);
246 }
247 
248 void tipc_publ_notify(struct net *net, struct list_head *nsub_list, u32 addr)
249 {
250 	struct publication *publ, *tmp;
251 
252 	list_for_each_entry_safe(publ, tmp, nsub_list, nodesub_list)
253 		tipc_publ_purge(net, publ, addr);
254 	tipc_dist_queue_purge(net, addr);
255 }
256 
257 /**
258  * tipc_update_nametbl - try to process a nametable update and notify
259  *			 subscribers
260  *
261  * tipc_nametbl_lock must be held.
262  * Returns the publication item if successful, otherwise NULL.
263  */
264 static bool tipc_update_nametbl(struct net *net, struct distr_item *i,
265 				u32 node, u32 dtype)
266 {
267 	struct publication *publ = NULL;
268 
269 	if (dtype == PUBLICATION) {
270 		publ = tipc_nametbl_insert_publ(net, ntohl(i->type),
271 						ntohl(i->lower),
272 						ntohl(i->upper),
273 						TIPC_CLUSTER_SCOPE, node,
274 						ntohl(i->ref), ntohl(i->key));
275 		if (publ) {
276 			tipc_node_subscribe(net, &publ->nodesub_list, node);
277 			return true;
278 		}
279 	} else if (dtype == WITHDRAWAL) {
280 		publ = tipc_nametbl_remove_publ(net, ntohl(i->type),
281 						ntohl(i->lower),
282 						node, ntohl(i->ref),
283 						ntohl(i->key));
284 		if (publ) {
285 			tipc_node_unsubscribe(net, &publ->nodesub_list, node);
286 			kfree_rcu(publ, rcu);
287 			return true;
288 		}
289 	} else {
290 		pr_warn("Unrecognized name table message received\n");
291 	}
292 	return false;
293 }
294 
295 /**
296  * tipc_named_add_backlog - add a failed name table update to the backlog
297  *
298  */
299 static void tipc_named_add_backlog(struct net *net, struct distr_item *i,
300 				   u32 type, u32 node)
301 {
302 	struct distr_queue_item *e;
303 	struct tipc_net *tn = net_generic(net, tipc_net_id);
304 	unsigned long now = get_jiffies_64();
305 
306 	e = kzalloc(sizeof(*e), GFP_ATOMIC);
307 	if (!e)
308 		return;
309 	e->dtype = type;
310 	e->node = node;
311 	e->expires = now + msecs_to_jiffies(sysctl_tipc_named_timeout);
312 	memcpy(e, i, sizeof(*i));
313 	list_add_tail(&e->next, &tn->dist_queue);
314 }
315 
316 /**
317  * tipc_named_process_backlog - try to process any pending name table updates
318  * from the network.
319  */
320 void tipc_named_process_backlog(struct net *net)
321 {
322 	struct distr_queue_item *e, *tmp;
323 	struct tipc_net *tn = net_generic(net, tipc_net_id);
324 	char addr[16];
325 	unsigned long now = get_jiffies_64();
326 
327 	list_for_each_entry_safe(e, tmp, &tn->dist_queue, next) {
328 		if (time_after(e->expires, now)) {
329 			if (!tipc_update_nametbl(net, &e->i, e->node, e->dtype))
330 				continue;
331 		} else {
332 			tipc_addr_string_fill(addr, e->node);
333 			pr_warn_ratelimited("Dropping name table update (%d) of {%u, %u, %u} from %s key=%u\n",
334 					    e->dtype, ntohl(e->i.type),
335 					    ntohl(e->i.lower),
336 					    ntohl(e->i.upper),
337 					    addr, ntohl(e->i.key));
338 		}
339 		list_del(&e->next);
340 		kfree(e);
341 	}
342 }
343 
344 /**
345  * tipc_named_rcv - process name table update messages sent by another node
346  */
347 void tipc_named_rcv(struct net *net, struct sk_buff_head *inputq)
348 {
349 	struct tipc_net *tn = net_generic(net, tipc_net_id);
350 	struct tipc_msg *msg;
351 	struct distr_item *item;
352 	uint count;
353 	u32 node;
354 	struct sk_buff *skb;
355 	int mtype;
356 
357 	spin_lock_bh(&tn->nametbl_lock);
358 	for (skb = skb_dequeue(inputq); skb; skb = skb_dequeue(inputq)) {
359 		skb_linearize(skb);
360 		msg = buf_msg(skb);
361 		mtype = msg_type(msg);
362 		item = (struct distr_item *)msg_data(msg);
363 		count = msg_data_sz(msg) / ITEM_SIZE;
364 		node = msg_orignode(msg);
365 		while (count--) {
366 			if (!tipc_update_nametbl(net, item, node, mtype))
367 				tipc_named_add_backlog(net, item, mtype, node);
368 			item++;
369 		}
370 		kfree_skb(skb);
371 		tipc_named_process_backlog(net);
372 	}
373 	spin_unlock_bh(&tn->nametbl_lock);
374 }
375 
376 /**
377  * tipc_named_reinit - re-initialize local publications
378  *
379  * This routine is called whenever TIPC networking is enabled.
380  * All name table entries published by this node are updated to reflect
381  * the node's new network address.
382  */
383 void tipc_named_reinit(struct net *net)
384 {
385 	struct tipc_net *tn = net_generic(net, tipc_net_id);
386 	struct publication *publ;
387 	int scope;
388 
389 	spin_lock_bh(&tn->nametbl_lock);
390 
391 	for (scope = TIPC_ZONE_SCOPE; scope <= TIPC_NODE_SCOPE; scope++)
392 		list_for_each_entry_rcu(publ, &tn->nametbl->publ_list[scope],
393 					local_list)
394 			publ->node = tn->own_addr;
395 
396 	spin_unlock_bh(&tn->nametbl_lock);
397 }
398