xref: /openbmc/linux/net/tipc/name_distr.c (revision 6c33a6f4)
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->port = htonl(p->port);
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 sk_buff *buf = tipc_buf_acquire(INT_H_SIZE + size, GFP_ATOMIC);
72 	u32 self = tipc_own_addr(net);
73 	struct tipc_msg *msg;
74 
75 	if (buf != NULL) {
76 		msg = buf_msg(buf);
77 		tipc_msg_init(self, msg, NAME_DISTRIBUTOR,
78 			      type, 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 name_table *nt = tipc_name_table(net);
90 	struct distr_item *item;
91 	struct sk_buff *skb;
92 
93 	if (publ->scope == TIPC_NODE_SCOPE) {
94 		list_add_tail_rcu(&publ->binding_node, &nt->node_scope);
95 		return NULL;
96 	}
97 	write_lock_bh(&nt->cluster_scope_lock);
98 	list_add_tail(&publ->binding_node, &nt->cluster_scope);
99 	write_unlock_bh(&nt->cluster_scope_lock);
100 	skb = named_prepare_buf(net, PUBLICATION, ITEM_SIZE, 0);
101 	if (!skb) {
102 		pr_warn("Publication distribution failure\n");
103 		return NULL;
104 	}
105 
106 	item = (struct distr_item *)msg_data(buf_msg(skb));
107 	publ_to_item(item, publ);
108 	return skb;
109 }
110 
111 /**
112  * tipc_named_withdraw - tell other nodes about a withdrawn publication by this node
113  */
114 struct sk_buff *tipc_named_withdraw(struct net *net, struct publication *publ)
115 {
116 	struct name_table *nt = tipc_name_table(net);
117 	struct sk_buff *buf;
118 	struct distr_item *item;
119 
120 	write_lock_bh(&nt->cluster_scope_lock);
121 	list_del(&publ->binding_node);
122 	write_unlock_bh(&nt->cluster_scope_lock);
123 	if (publ->scope == TIPC_NODE_SCOPE)
124 		return NULL;
125 
126 	buf = named_prepare_buf(net, WITHDRAWAL, ITEM_SIZE, 0);
127 	if (!buf) {
128 		pr_warn("Withdrawal distribution failure\n");
129 		return NULL;
130 	}
131 
132 	item = (struct distr_item *)msg_data(buf_msg(buf));
133 	publ_to_item(item, publ);
134 	return buf;
135 }
136 
137 /**
138  * named_distribute - prepare name info for bulk distribution to another node
139  * @list: list of messages (buffers) to be returned from this function
140  * @dnode: node to be updated
141  * @pls: linked list of publication items to be packed into buffer chain
142  */
143 static void named_distribute(struct net *net, struct sk_buff_head *list,
144 			     u32 dnode, struct list_head *pls)
145 {
146 	struct publication *publ;
147 	struct sk_buff *skb = NULL;
148 	struct distr_item *item = NULL;
149 	u32 msg_dsz = ((tipc_node_get_mtu(net, dnode, 0, false) - INT_H_SIZE) /
150 			ITEM_SIZE) * ITEM_SIZE;
151 	u32 msg_rem = msg_dsz;
152 
153 	list_for_each_entry(publ, pls, binding_node) {
154 		/* Prepare next buffer: */
155 		if (!skb) {
156 			skb = named_prepare_buf(net, PUBLICATION, msg_rem,
157 						dnode);
158 			if (!skb) {
159 				pr_warn("Bulk publication failure\n");
160 				return;
161 			}
162 			msg_set_bc_ack_invalid(buf_msg(skb), true);
163 			item = (struct distr_item *)msg_data(buf_msg(skb));
164 		}
165 
166 		/* Pack publication into message: */
167 		publ_to_item(item, publ);
168 		item++;
169 		msg_rem -= ITEM_SIZE;
170 
171 		/* Append full buffer to list: */
172 		if (!msg_rem) {
173 			__skb_queue_tail(list, skb);
174 			skb = NULL;
175 			msg_rem = msg_dsz;
176 		}
177 	}
178 	if (skb) {
179 		msg_set_size(buf_msg(skb), INT_H_SIZE + (msg_dsz - msg_rem));
180 		skb_trim(skb, INT_H_SIZE + (msg_dsz - msg_rem));
181 		__skb_queue_tail(list, skb);
182 	}
183 }
184 
185 /**
186  * tipc_named_node_up - tell specified node about all publications by this node
187  */
188 void tipc_named_node_up(struct net *net, u32 dnode)
189 {
190 	struct name_table *nt = tipc_name_table(net);
191 	struct sk_buff_head head;
192 
193 	__skb_queue_head_init(&head);
194 
195 	read_lock_bh(&nt->cluster_scope_lock);
196 	named_distribute(net, &head, dnode, &nt->cluster_scope);
197 	tipc_node_xmit(net, &head, dnode, 0);
198 	read_unlock_bh(&nt->cluster_scope_lock);
199 }
200 
201 /**
202  * tipc_publ_purge - remove publication associated with a failed node
203  *
204  * Invoked for each publication issued by a newly failed node.
205  * Removes publication structure from name table & deletes it.
206  */
207 static void tipc_publ_purge(struct net *net, struct publication *publ, u32 addr)
208 {
209 	struct tipc_net *tn = tipc_net(net);
210 	struct publication *p;
211 
212 	spin_lock_bh(&tn->nametbl_lock);
213 	p = tipc_nametbl_remove_publ(net, publ->type, publ->lower, publ->upper,
214 				     publ->node, publ->key);
215 	if (p)
216 		tipc_node_unsubscribe(net, &p->binding_node, addr);
217 	spin_unlock_bh(&tn->nametbl_lock);
218 
219 	if (p != publ) {
220 		pr_err("Unable to remove publication from failed node\n"
221 		       " (type=%u, lower=%u, node=0x%x, port=%u, key=%u)\n",
222 		       publ->type, publ->lower, publ->node, publ->port,
223 		       publ->key);
224 	}
225 
226 	if (p)
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, binding_node)
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 *p = NULL;
268 	u32 lower = ntohl(i->lower);
269 	u32 upper = ntohl(i->upper);
270 	u32 type = ntohl(i->type);
271 	u32 port = ntohl(i->port);
272 	u32 key = ntohl(i->key);
273 
274 	if (dtype == PUBLICATION) {
275 		p = tipc_nametbl_insert_publ(net, type, lower, upper,
276 					     TIPC_CLUSTER_SCOPE, node,
277 					     port, key);
278 		if (p) {
279 			tipc_node_subscribe(net, &p->binding_node, node);
280 			return true;
281 		}
282 	} else if (dtype == WITHDRAWAL) {
283 		p = tipc_nametbl_remove_publ(net, type, lower,
284 					     upper, node, key);
285 		if (p) {
286 			tipc_node_unsubscribe(net, &p->binding_node, node);
287 			kfree_rcu(p, rcu);
288 			return true;
289 		}
290 		pr_warn_ratelimited("Failed to remove binding %u,%u from %x\n",
291 				    type, lower, node);
292 	} else {
293 		pr_warn("Unrecognized name table message received\n");
294 	}
295 	return false;
296 }
297 
298 /**
299  * tipc_named_rcv - process name table update messages sent by another node
300  */
301 void tipc_named_rcv(struct net *net, struct sk_buff_head *inputq)
302 {
303 	struct tipc_net *tn = net_generic(net, tipc_net_id);
304 	struct tipc_msg *msg;
305 	struct distr_item *item;
306 	uint count;
307 	u32 node;
308 	struct sk_buff *skb;
309 	int mtype;
310 
311 	spin_lock_bh(&tn->nametbl_lock);
312 	for (skb = skb_dequeue(inputq); skb; skb = skb_dequeue(inputq)) {
313 		skb_linearize(skb);
314 		msg = buf_msg(skb);
315 		mtype = msg_type(msg);
316 		item = (struct distr_item *)msg_data(msg);
317 		count = msg_data_sz(msg) / ITEM_SIZE;
318 		node = msg_orignode(msg);
319 		while (count--) {
320 			tipc_update_nametbl(net, item, node, mtype);
321 			item++;
322 		}
323 		kfree_skb(skb);
324 	}
325 	spin_unlock_bh(&tn->nametbl_lock);
326 }
327 
328 /**
329  * tipc_named_reinit - re-initialize local publications
330  *
331  * This routine is called whenever TIPC networking is enabled.
332  * All name table entries published by this node are updated to reflect
333  * the node's new network address.
334  */
335 void tipc_named_reinit(struct net *net)
336 {
337 	struct name_table *nt = tipc_name_table(net);
338 	struct tipc_net *tn = tipc_net(net);
339 	struct publication *publ;
340 	u32 self = tipc_own_addr(net);
341 
342 	spin_lock_bh(&tn->nametbl_lock);
343 
344 	list_for_each_entry_rcu(publ, &nt->node_scope, binding_node)
345 		publ->node = self;
346 	list_for_each_entry_rcu(publ, &nt->cluster_scope, binding_node)
347 		publ->node = self;
348 
349 	spin_unlock_bh(&tn->nametbl_lock);
350 }
351