summaryrefslogtreecommitdiffstats
path: root/net/tipc/name_distr.c
blob: 2f9c148f17e27e1d838773a0029188b21a6ed4fa (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
/*
 * net/tipc/name_distr.c: TIPC name distribution code
 *
 * Copyright (c) 2000-2006, 2014, Ericsson AB
 * Copyright (c) 2005, 2010-2011, Wind River Systems
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the names of the copyright holders nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include "core.h"
#include "link.h"
#include "name_distr.h"

int sysctl_tipc_named_timeout __read_mostly = 2000;

struct distr_queue_item {
	struct distr_item i;
	u32 dtype;
	u32 node;
	unsigned long expires;
	struct list_head next;
};

/**
 * publ_to_item - add publication info to a publication message
 */
static void publ_to_item(struct distr_item *i, struct publication *p)
{
	i->type = htonl(p->type);
	i->lower = htonl(p->lower);
	i->upper = htonl(p->upper);
	i->port = htonl(p->port);
	i->key = htonl(p->key);
}

/**
 * named_prepare_buf - allocate & initialize a publication message
 *
 * The buffer returned is of size INT_H_SIZE + payload size
 */
static struct sk_buff *named_prepare_buf(struct net *net, u32 type, u32 size,
					 u32 dest)
{
	struct sk_buff *buf = tipc_buf_acquire(INT_H_SIZE + size, GFP_ATOMIC);
	u32 self = tipc_own_addr(net);
	struct tipc_msg *msg;

	if (buf != NULL) {
		msg = buf_msg(buf);
		tipc_msg_init(self, msg, NAME_DISTRIBUTOR,
			      type, INT_H_SIZE, dest);
		msg_set_size(msg, INT_H_SIZE + size);
	}
	return buf;
}

/**
 * tipc_named_publish - tell other nodes about a new publication by this node
 */
struct sk_buff *tipc_named_publish(struct net *net, struct publication *publ)
{
	struct name_table *nt = tipc_name_table(net);
	struct distr_item *item;
	struct sk_buff *skb;

	if (publ->scope == TIPC_NODE_SCOPE) {
		list_add_tail_rcu(&publ->binding_node, &nt->node_scope);
		return NULL;
	}
	write_lock_bh(&nt->cluster_scope_lock);
	list_add_tail(&publ->binding_node, &nt->cluster_scope);
	write_unlock_bh(&nt->cluster_scope_lock);
	skb = named_prepare_buf(net, PUBLICATION, ITEM_SIZE, 0);
	if (!skb) {
		pr_warn("Publication distribution failure\n");
		return NULL;
	}
	msg_set_named_seqno(buf_msg(skb), nt->snd_nxt++);
	msg_set_non_legacy(buf_msg(skb));
	item = (struct distr_item *)msg_data(buf_msg(skb));
	publ_to_item(item, publ);
	return skb;
}

/**
 * tipc_named_withdraw - tell other nodes about a withdrawn publication by this node
 */
struct sk_buff *tipc_named_withdraw(struct net *net, struct publication *publ)
{
	struct name_table *nt = tipc_name_table(net);
	struct distr_item *item;
	struct sk_buff *skb;

	write_lock_bh(&nt->cluster_scope_lock);
	list_del(&publ->binding_node);
	write_unlock_bh(&nt->cluster_scope_lock);
	if (publ->scope == TIPC_NODE_SCOPE)
		return NULL;

	skb = named_prepare_buf(net, WITHDRAWAL, ITEM_SIZE, 0);
	if (!skb) {
		pr_warn("Withdrawal distribution failure\n");
		return NULL;
	}
	msg_set_named_seqno(buf_msg(skb), nt->snd_nxt++);
	msg_set_non_legacy(buf_msg(skb));
	item = (struct distr_item *)msg_data(buf_msg(skb));
	publ_to_item(item, publ);
	return skb;
}

/**
 * named_distribute - prepare name info for bulk distribution to another node
 * @list: list of messages (buffers) to be returned from this function
 * @dnode: node to be updated
 * @pls: linked list of publication items to be packed into buffer chain
 */
static void named_distribute(struct net *net, struct sk_buff_head *list,
			     u32 dnode, struct list_head *pls, u16 seqno)
{
	struct publication *publ;
	struct sk_buff *skb = NULL;
	struct distr_item *item = NULL;
	u32 msg_dsz = ((tipc_node_get_mtu(net, dnode, 0, false) - INT_H_SIZE) /
			ITEM_SIZE) * ITEM_SIZE;
	u32 msg_rem = msg_dsz;
	struct tipc_msg *hdr;

	list_for_each_entry(publ, pls, binding_node) {
		/* Prepare next buffer: */
		if (!skb) {
			skb = named_prepare_buf(net, PUBLICATION, msg_rem,
						dnode);
			if (!skb) {
				pr_warn("Bulk publication failure\n");
				return;
			}
			hdr = buf_msg(skb);
			msg_set_bc_ack_invalid(hdr, true);
			msg_set_bulk(hdr);
			msg_set_non_legacy(hdr);
			item = (struct distr_item *)msg_data(hdr);
		}

		/* Pack publication into message: */
		publ_to_item(item, publ);
		item++;
		msg_rem -= ITEM_SIZE;

		/* Append full buffer to list: */
		if (!msg_rem) {
			__skb_queue_tail(list, skb);
			skb = NULL;
			msg_rem = msg_dsz;
		}
	}
	if (skb) {
		hdr = buf_msg(skb);
		msg_set_size(hdr, INT_H_SIZE + (msg_dsz - msg_rem));
		skb_trim(skb, INT_H_SIZE + (msg_dsz - msg_rem));
		__skb_queue_tail(list, skb);
	}
	hdr = buf_msg(skb_peek_tail(list));
	msg_set_last_bulk(hdr);
	msg_set_named_seqno(hdr, seqno);
}

/**
 * tipc_named_node_up - tell specified node about all publications by this node
 */
void tipc_named_node_up(struct net *net, u32 dnode, u16 capabilities)
{
	struct name_table *nt = tipc_name_table(net);
	struct tipc_net *tn = tipc_net(net);
	struct sk_buff_head head;
	u16 seqno;

	__skb_queue_head_init(&head);
	spin_lock_bh(&tn->nametbl_lock);
	if (!(capabilities & TIPC_NAMED_BCAST))
		nt->rc_dests++;
	seqno = nt->snd_nxt;
	spin_unlock_bh(&tn->nametbl_lock);

	read_lock_bh(&nt->cluster_scope_lock);
	named_distribute(net, &head, dnode, &nt->cluster_scope, seqno);
	tipc_node_xmit(net, &head, dnode, 0);
	read_unlock_bh(&nt->cluster_scope_lock);
}

/**
 * tipc_publ_purge - remove publication associated with a failed node
 *
 * Invoked for each publication issued by a newly failed node.
 * Removes publication structure from name table & deletes it.
 */
static void tipc_publ_purge(struct net *net, struct publication *publ, u32 addr)
{
	struct tipc_net *tn = tipc_net(net);
	struct publication *p;

	spin_lock_bh(&tn->nametbl_lock);
	p = tipc_nametbl_remove_publ(net, publ->type, publ->lower, publ->upper,
				     publ->node, publ->key);
	if (p)
		tipc_node_unsubscribe(net, &p->binding_node, addr);
	spin_unlock_bh(&tn->nametbl_lock);

	if (p != publ) {
		pr_err("Unable to remove publication from failed node\n"
		       " (type=%u, lower=%u, node=0x%x, port=%u, key=%u)\n",
		       publ->type, publ->lower, publ->node, publ->port,
		       publ->key);
	}

	if (p)
		kfree_rcu(p, rcu);
}

/**
 * tipc_dist_queue_purge - remove deferred updates from a node that went down
 */
static void tipc_dist_queue_purge(struct net *net, u32 addr)
{
	struct tipc_net *tn = net_generic(net, tipc_net_id);
	struct distr_queue_item *e, *tmp;

	spin_lock_bh(&tn->nametbl_lock);
	list_for_each_entry_safe(e, tmp, &tn->dist_queue, next) {
		if (e->node != addr)
			continue;
		list_del(&e->next);
		kfree(e);
	}
	spin_unlock_bh(&tn->nametbl_lock);
}

void tipc_publ_notify(struct net *net, struct list_head *nsub_list,
		      u32 addr, u16 capabilities)
{
	struct name_table *nt = tipc_name_table(net);
	struct tipc_net *tn = tipc_net(net);

	struct publication *publ, *tmp;

	list_for_each_entry_safe(publ, tmp, nsub_list, binding_node)
		tipc_publ_purge(net, publ, addr);
	tipc_dist_queue_purge(net, addr);
	spin_lock_bh(&tn->nametbl_lock);
	if (!(capabilities & TIPC_NAMED_BCAST))
		nt->rc_dests--;
	spin_unlock_bh(&tn->nametbl_lock);
}

/**
 * tipc_update_nametbl - try to process a nametable update and notify
 *			 subscribers
 *
 * tipc_nametbl_lock must be held.
 * Returns the publication item if successful, otherwise NULL.
 */
static bool tipc_update_nametbl(struct net *net, struct distr_item *i,
				u32 node, u32 dtype)
{
	struct publication *p = NULL;
	u32 lower = ntohl(i->lower);
	u32 upper = ntohl(i->upper);
	u32 type = ntohl(i->type);
	u32 port = ntohl(i->port);
	u32 key = ntohl(i->key);

	if (dtype == PUBLICATION) {
		p = tipc_nametbl_insert_publ(net, type, lower, upper,
					     TIPC_CLUSTER_SCOPE, node,
					     port, key);
		if (p) {
			tipc_node_subscribe(net, &p->binding_node, node);
			return true;
		}
	} else if (dtype == WITHDRAWAL) {
		p = tipc_nametbl_remove_publ(net, type, lower,
					     upper, node, key);
		if (p) {
			tipc_node_unsubscribe(net, &p->binding_node, node);
			kfree_rcu(p, rcu);
			return true;
		}
		pr_warn_ratelimited("Failed to remove binding %u,%u from %x\n",
				    type, lower, node);
	} else {
		pr_warn("Unrecognized name table message received\n");
	}
	return false;
}

static struct sk_buff *tipc_named_dequeue(struct sk_buff_head *namedq,
					  u16 *rcv_nxt, bool *open)
{
	struct sk_buff *skb, *tmp;
	struct tipc_msg *hdr;
	u16 seqno;

	skb_queue_walk_safe(namedq, skb, tmp) {
		skb_linearize(skb);
		hdr = buf_msg(skb);
		seqno = msg_named_seqno(hdr);
		if (msg_is_last_bulk(hdr)) {
			*rcv_nxt = seqno;
			*open = true;
		}

		if (msg_is_bulk(hdr) || msg_is_legacy(hdr)) {
			__skb_unlink(skb, namedq);
			return skb;
		}

		if (*open && (*rcv_nxt == seqno)) {
			(*rcv_nxt)++;
			__skb_unlink(skb, namedq);
			return skb;
		}

		if (less(seqno, *rcv_nxt)) {
			__skb_unlink(skb, namedq);
			kfree_skb(skb);
			continue;
		}
	}
	return NULL;
}

/**
 * tipc_named_rcv - process name table update messages sent by another node
 */
void tipc_named_rcv(struct net *net, struct sk_buff_head *namedq,
		    u16 *rcv_nxt, bool *open)
{
	struct tipc_net *tn = tipc_net(net);
	struct distr_item *item;
	struct tipc_msg *hdr;
	struct sk_buff *skb;
	u32 count, node;

	spin_lock_bh(&tn->nametbl_lock);
	while ((skb = tipc_named_dequeue(namedq, rcv_nxt, open))) {
		hdr = buf_msg(skb);
		node = msg_orignode(hdr);
		item = (struct distr_item *)msg_data(hdr);
		count = msg_data_sz(hdr) / ITEM_SIZE;
		while (count--) {
			tipc_update_nametbl(net, item, node, msg_type(hdr));
			item++;
		}
		kfree_skb(skb);
	}
	spin_unlock_bh(&tn->nametbl_lock);
}

/**
 * tipc_named_reinit - re-initialize local publications
 *
 * This routine is called whenever TIPC networking is enabled.
 * All name table entries published by this node are updated to reflect
 * the node's new network address.
 */
void tipc_named_reinit(struct net *net)
{
	struct name_table *nt = tipc_name_table(net);
	struct tipc_net *tn = tipc_net(net);
	struct publication *publ;
	u32 self = tipc_own_addr(net);

	spin_lock_bh(&tn->nametbl_lock);

	list_for_each_entry_rcu(publ, &nt->node_scope, binding_node)
		publ->node = self;
	list_for_each_entry_rcu(publ, &nt->cluster_scope, binding_node)
		publ->node = self;
	nt->rc_dests = 0;
	spin_unlock_bh(&tn->nametbl_lock);
}