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Merge tag 'pinctrl-v4.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw...
[mirror_ubuntu-zesty-kernel.git] / net / tipc / link.c
1 /*
2 * net/tipc/link.c: TIPC link code
3 *
4 * Copyright (c) 1996-2007, 2012-2014, Ericsson AB
5 * Copyright (c) 2004-2007, 2010-2013, 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 "bcast.h"
40 #include "socket.h"
41 #include "name_distr.h"
42 #include "discover.h"
43 #include "netlink.h"
44
45 #include <linux/pkt_sched.h>
46
47 /*
48 * Error message prefixes
49 */
50 static const char *link_co_err = "Link changeover error, ";
51 static const char *link_rst_msg = "Resetting link ";
52 static const char *link_unk_evt = "Unknown link event ";
53
54 static const struct nla_policy tipc_nl_link_policy[TIPC_NLA_LINK_MAX + 1] = {
55 [TIPC_NLA_LINK_UNSPEC] = { .type = NLA_UNSPEC },
56 [TIPC_NLA_LINK_NAME] = {
57 .type = NLA_STRING,
58 .len = TIPC_MAX_LINK_NAME
59 },
60 [TIPC_NLA_LINK_MTU] = { .type = NLA_U32 },
61 [TIPC_NLA_LINK_BROADCAST] = { .type = NLA_FLAG },
62 [TIPC_NLA_LINK_UP] = { .type = NLA_FLAG },
63 [TIPC_NLA_LINK_ACTIVE] = { .type = NLA_FLAG },
64 [TIPC_NLA_LINK_PROP] = { .type = NLA_NESTED },
65 [TIPC_NLA_LINK_STATS] = { .type = NLA_NESTED },
66 [TIPC_NLA_LINK_RX] = { .type = NLA_U32 },
67 [TIPC_NLA_LINK_TX] = { .type = NLA_U32 }
68 };
69
70 /* Properties valid for media, bearar and link */
71 static const struct nla_policy tipc_nl_prop_policy[TIPC_NLA_PROP_MAX + 1] = {
72 [TIPC_NLA_PROP_UNSPEC] = { .type = NLA_UNSPEC },
73 [TIPC_NLA_PROP_PRIO] = { .type = NLA_U32 },
74 [TIPC_NLA_PROP_TOL] = { .type = NLA_U32 },
75 [TIPC_NLA_PROP_WIN] = { .type = NLA_U32 }
76 };
77
78 /*
79 * Out-of-range value for link session numbers
80 */
81 #define INVALID_SESSION 0x10000
82
83 /*
84 * Link state events:
85 */
86 #define STARTING_EVT 856384768 /* link processing trigger */
87 #define TRAFFIC_MSG_EVT 560815u /* rx'd ??? */
88 #define TIMEOUT_EVT 560817u /* link timer expired */
89
90 /*
91 * The following two 'message types' is really just implementation
92 * data conveniently stored in the message header.
93 * They must not be considered part of the protocol
94 */
95 #define OPEN_MSG 0
96 #define CLOSED_MSG 1
97
98 /*
99 * State value stored in 'exp_msg_count'
100 */
101 #define START_CHANGEOVER 100000u
102
103 static void link_handle_out_of_seq_msg(struct tipc_link *link,
104 struct sk_buff *skb);
105 static void tipc_link_proto_rcv(struct tipc_link *link,
106 struct sk_buff *skb);
107 static int tipc_link_tunnel_rcv(struct tipc_node *node,
108 struct sk_buff **skb);
109 static void link_set_supervision_props(struct tipc_link *l_ptr, u32 tol);
110 static void link_state_event(struct tipc_link *l_ptr, u32 event);
111 static void link_reset_statistics(struct tipc_link *l_ptr);
112 static void link_print(struct tipc_link *l_ptr, const char *str);
113 static void tipc_link_sync_xmit(struct tipc_link *l);
114 static void tipc_link_sync_rcv(struct tipc_node *n, struct sk_buff *buf);
115 static void tipc_link_input(struct tipc_link *l, struct sk_buff *skb);
116 static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb);
117
118 /*
119 * Simple link routines
120 */
121 static unsigned int align(unsigned int i)
122 {
123 return (i + 3) & ~3u;
124 }
125
126 static void tipc_link_release(struct kref *kref)
127 {
128 kfree(container_of(kref, struct tipc_link, ref));
129 }
130
131 static void tipc_link_get(struct tipc_link *l_ptr)
132 {
133 kref_get(&l_ptr->ref);
134 }
135
136 static void tipc_link_put(struct tipc_link *l_ptr)
137 {
138 kref_put(&l_ptr->ref, tipc_link_release);
139 }
140
141 static void link_init_max_pkt(struct tipc_link *l_ptr)
142 {
143 struct tipc_node *node = l_ptr->owner;
144 struct tipc_net *tn = net_generic(node->net, tipc_net_id);
145 struct tipc_bearer *b_ptr;
146 u32 max_pkt;
147
148 rcu_read_lock();
149 b_ptr = rcu_dereference_rtnl(tn->bearer_list[l_ptr->bearer_id]);
150 if (!b_ptr) {
151 rcu_read_unlock();
152 return;
153 }
154 max_pkt = (b_ptr->mtu & ~3);
155 rcu_read_unlock();
156
157 if (max_pkt > MAX_MSG_SIZE)
158 max_pkt = MAX_MSG_SIZE;
159
160 l_ptr->max_pkt_target = max_pkt;
161 if (l_ptr->max_pkt_target < MAX_PKT_DEFAULT)
162 l_ptr->max_pkt = l_ptr->max_pkt_target;
163 else
164 l_ptr->max_pkt = MAX_PKT_DEFAULT;
165
166 l_ptr->max_pkt_probes = 0;
167 }
168
169 /*
170 * Simple non-static link routines (i.e. referenced outside this file)
171 */
172 int tipc_link_is_up(struct tipc_link *l_ptr)
173 {
174 if (!l_ptr)
175 return 0;
176 return link_working_working(l_ptr) || link_working_unknown(l_ptr);
177 }
178
179 int tipc_link_is_active(struct tipc_link *l_ptr)
180 {
181 return (l_ptr->owner->active_links[0] == l_ptr) ||
182 (l_ptr->owner->active_links[1] == l_ptr);
183 }
184
185 /**
186 * link_timeout - handle expiration of link timer
187 * @l_ptr: pointer to link
188 */
189 static void link_timeout(unsigned long data)
190 {
191 struct tipc_link *l_ptr = (struct tipc_link *)data;
192 struct sk_buff *skb;
193
194 tipc_node_lock(l_ptr->owner);
195
196 /* update counters used in statistical profiling of send traffic */
197 l_ptr->stats.accu_queue_sz += skb_queue_len(&l_ptr->outqueue);
198 l_ptr->stats.queue_sz_counts++;
199
200 skb = skb_peek(&l_ptr->outqueue);
201 if (skb) {
202 struct tipc_msg *msg = buf_msg(skb);
203 u32 length = msg_size(msg);
204
205 if ((msg_user(msg) == MSG_FRAGMENTER) &&
206 (msg_type(msg) == FIRST_FRAGMENT)) {
207 length = msg_size(msg_get_wrapped(msg));
208 }
209 if (length) {
210 l_ptr->stats.msg_lengths_total += length;
211 l_ptr->stats.msg_length_counts++;
212 if (length <= 64)
213 l_ptr->stats.msg_length_profile[0]++;
214 else if (length <= 256)
215 l_ptr->stats.msg_length_profile[1]++;
216 else if (length <= 1024)
217 l_ptr->stats.msg_length_profile[2]++;
218 else if (length <= 4096)
219 l_ptr->stats.msg_length_profile[3]++;
220 else if (length <= 16384)
221 l_ptr->stats.msg_length_profile[4]++;
222 else if (length <= 32768)
223 l_ptr->stats.msg_length_profile[5]++;
224 else
225 l_ptr->stats.msg_length_profile[6]++;
226 }
227 }
228
229 /* do all other link processing performed on a periodic basis */
230 link_state_event(l_ptr, TIMEOUT_EVT);
231
232 if (l_ptr->next_out)
233 tipc_link_push_packets(l_ptr);
234
235 tipc_node_unlock(l_ptr->owner);
236 tipc_link_put(l_ptr);
237 }
238
239 static void link_set_timer(struct tipc_link *link, unsigned long time)
240 {
241 if (!mod_timer(&link->timer, jiffies + time))
242 tipc_link_get(link);
243 }
244
245 /**
246 * tipc_link_create - create a new link
247 * @n_ptr: pointer to associated node
248 * @b_ptr: pointer to associated bearer
249 * @media_addr: media address to use when sending messages over link
250 *
251 * Returns pointer to link.
252 */
253 struct tipc_link *tipc_link_create(struct tipc_node *n_ptr,
254 struct tipc_bearer *b_ptr,
255 const struct tipc_media_addr *media_addr)
256 {
257 struct tipc_net *tn = net_generic(n_ptr->net, tipc_net_id);
258 struct tipc_link *l_ptr;
259 struct tipc_msg *msg;
260 char *if_name;
261 char addr_string[16];
262 u32 peer = n_ptr->addr;
263
264 if (n_ptr->link_cnt >= MAX_BEARERS) {
265 tipc_addr_string_fill(addr_string, n_ptr->addr);
266 pr_err("Attempt to establish %uth link to %s. Max %u allowed.\n",
267 n_ptr->link_cnt, addr_string, MAX_BEARERS);
268 return NULL;
269 }
270
271 if (n_ptr->links[b_ptr->identity]) {
272 tipc_addr_string_fill(addr_string, n_ptr->addr);
273 pr_err("Attempt to establish second link on <%s> to %s\n",
274 b_ptr->name, addr_string);
275 return NULL;
276 }
277
278 l_ptr = kzalloc(sizeof(*l_ptr), GFP_ATOMIC);
279 if (!l_ptr) {
280 pr_warn("Link creation failed, no memory\n");
281 return NULL;
282 }
283 kref_init(&l_ptr->ref);
284 l_ptr->addr = peer;
285 if_name = strchr(b_ptr->name, ':') + 1;
286 sprintf(l_ptr->name, "%u.%u.%u:%s-%u.%u.%u:unknown",
287 tipc_zone(tn->own_addr), tipc_cluster(tn->own_addr),
288 tipc_node(tn->own_addr),
289 if_name,
290 tipc_zone(peer), tipc_cluster(peer), tipc_node(peer));
291 /* note: peer i/f name is updated by reset/activate message */
292 memcpy(&l_ptr->media_addr, media_addr, sizeof(*media_addr));
293 l_ptr->owner = n_ptr;
294 l_ptr->checkpoint = 1;
295 l_ptr->peer_session = INVALID_SESSION;
296 l_ptr->bearer_id = b_ptr->identity;
297 link_set_supervision_props(l_ptr, b_ptr->tolerance);
298 l_ptr->state = RESET_UNKNOWN;
299
300 l_ptr->pmsg = (struct tipc_msg *)&l_ptr->proto_msg;
301 msg = l_ptr->pmsg;
302 tipc_msg_init(tn->own_addr, msg, LINK_PROTOCOL, RESET_MSG, INT_H_SIZE,
303 l_ptr->addr);
304 msg_set_size(msg, sizeof(l_ptr->proto_msg));
305 msg_set_session(msg, (tn->random & 0xffff));
306 msg_set_bearer_id(msg, b_ptr->identity);
307 strcpy((char *)msg_data(msg), if_name);
308
309 l_ptr->priority = b_ptr->priority;
310 tipc_link_set_queue_limits(l_ptr, b_ptr->window);
311
312 l_ptr->net_plane = b_ptr->net_plane;
313 link_init_max_pkt(l_ptr);
314
315 l_ptr->next_out_no = 1;
316 __skb_queue_head_init(&l_ptr->outqueue);
317 __skb_queue_head_init(&l_ptr->deferred_queue);
318 skb_queue_head_init(&l_ptr->wakeupq);
319 skb_queue_head_init(&l_ptr->inputq);
320 skb_queue_head_init(&l_ptr->namedq);
321 link_reset_statistics(l_ptr);
322 tipc_node_attach_link(n_ptr, l_ptr);
323 setup_timer(&l_ptr->timer, link_timeout, (unsigned long)l_ptr);
324 link_state_event(l_ptr, STARTING_EVT);
325
326 return l_ptr;
327 }
328
329 /**
330 * link_delete - Conditional deletion of link.
331 * If timer still running, real delete is done when it expires
332 * @link: link to be deleted
333 */
334 void tipc_link_delete(struct tipc_link *link)
335 {
336 tipc_link_reset_fragments(link);
337 tipc_node_detach_link(link->owner, link);
338 tipc_link_put(link);
339 }
340
341 void tipc_link_delete_list(struct net *net, unsigned int bearer_id,
342 bool shutting_down)
343 {
344 struct tipc_net *tn = net_generic(net, tipc_net_id);
345 struct tipc_link *link;
346 struct tipc_node *node;
347
348 rcu_read_lock();
349 list_for_each_entry_rcu(node, &tn->node_list, list) {
350 tipc_node_lock(node);
351 link = node->links[bearer_id];
352 if (!link) {
353 tipc_node_unlock(node);
354 continue;
355 }
356 tipc_link_reset(link);
357 if (del_timer(&link->timer))
358 tipc_link_put(link);
359 link->flags |= LINK_STOPPED;
360 /* Delete link now, or when failover is finished: */
361 if (shutting_down || !tipc_node_is_up(node))
362 tipc_link_delete(link);
363 tipc_node_unlock(node);
364 }
365 rcu_read_unlock();
366 }
367
368 /**
369 * link_schedule_user - schedule user for wakeup after congestion
370 * @link: congested link
371 * @oport: sending port
372 * @chain_sz: size of buffer chain that was attempted sent
373 * @imp: importance of message attempted sent
374 * Create pseudo msg to send back to user when congestion abates
375 */
376 static bool link_schedule_user(struct tipc_link *link, u32 oport,
377 uint chain_sz, uint imp)
378 {
379 struct sk_buff *buf;
380
381 buf = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0,
382 link_own_addr(link), link_own_addr(link),
383 oport, 0, 0);
384 if (!buf)
385 return false;
386 TIPC_SKB_CB(buf)->chain_sz = chain_sz;
387 TIPC_SKB_CB(buf)->chain_imp = imp;
388 skb_queue_tail(&link->wakeupq, buf);
389 link->stats.link_congs++;
390 return true;
391 }
392
393 /**
394 * link_prepare_wakeup - prepare users for wakeup after congestion
395 * @link: congested link
396 * Move a number of waiting users, as permitted by available space in
397 * the send queue, from link wait queue to node wait queue for wakeup
398 */
399 void link_prepare_wakeup(struct tipc_link *link)
400 {
401 uint pend_qsz = skb_queue_len(&link->outqueue);
402 struct sk_buff *skb, *tmp;
403
404 skb_queue_walk_safe(&link->wakeupq, skb, tmp) {
405 if (pend_qsz >= link->queue_limit[TIPC_SKB_CB(skb)->chain_imp])
406 break;
407 pend_qsz += TIPC_SKB_CB(skb)->chain_sz;
408 skb_unlink(skb, &link->wakeupq);
409 skb_queue_tail(&link->inputq, skb);
410 link->owner->inputq = &link->inputq;
411 link->owner->action_flags |= TIPC_MSG_EVT;
412 }
413 }
414
415 /**
416 * tipc_link_reset_fragments - purge link's inbound message fragments queue
417 * @l_ptr: pointer to link
418 */
419 void tipc_link_reset_fragments(struct tipc_link *l_ptr)
420 {
421 kfree_skb(l_ptr->reasm_buf);
422 l_ptr->reasm_buf = NULL;
423 }
424
425 /**
426 * tipc_link_purge_queues - purge all pkt queues associated with link
427 * @l_ptr: pointer to link
428 */
429 void tipc_link_purge_queues(struct tipc_link *l_ptr)
430 {
431 __skb_queue_purge(&l_ptr->deferred_queue);
432 __skb_queue_purge(&l_ptr->outqueue);
433 tipc_link_reset_fragments(l_ptr);
434 }
435
436 void tipc_link_reset(struct tipc_link *l_ptr)
437 {
438 u32 prev_state = l_ptr->state;
439 u32 checkpoint = l_ptr->next_in_no;
440 int was_active_link = tipc_link_is_active(l_ptr);
441 struct tipc_node *owner = l_ptr->owner;
442
443 msg_set_session(l_ptr->pmsg, ((msg_session(l_ptr->pmsg) + 1) & 0xffff));
444
445 /* Link is down, accept any session */
446 l_ptr->peer_session = INVALID_SESSION;
447
448 /* Prepare for max packet size negotiation */
449 link_init_max_pkt(l_ptr);
450
451 l_ptr->state = RESET_UNKNOWN;
452
453 if ((prev_state == RESET_UNKNOWN) || (prev_state == RESET_RESET))
454 return;
455
456 tipc_node_link_down(l_ptr->owner, l_ptr);
457 tipc_bearer_remove_dest(owner->net, l_ptr->bearer_id, l_ptr->addr);
458
459 if (was_active_link && tipc_node_active_links(l_ptr->owner)) {
460 l_ptr->reset_checkpoint = checkpoint;
461 l_ptr->exp_msg_count = START_CHANGEOVER;
462 }
463
464 /* Clean up all queues, except inputq: */
465 __skb_queue_purge(&l_ptr->outqueue);
466 __skb_queue_purge(&l_ptr->deferred_queue);
467 if (!owner->inputq)
468 owner->inputq = &l_ptr->inputq;
469 skb_queue_splice_init(&l_ptr->wakeupq, owner->inputq);
470 if (!skb_queue_empty(owner->inputq))
471 owner->action_flags |= TIPC_MSG_EVT;
472 l_ptr->next_out = NULL;
473 l_ptr->unacked_window = 0;
474 l_ptr->checkpoint = 1;
475 l_ptr->next_out_no = 1;
476 l_ptr->fsm_msg_cnt = 0;
477 l_ptr->stale_count = 0;
478 link_reset_statistics(l_ptr);
479 }
480
481 void tipc_link_reset_list(struct net *net, unsigned int bearer_id)
482 {
483 struct tipc_net *tn = net_generic(net, tipc_net_id);
484 struct tipc_link *l_ptr;
485 struct tipc_node *n_ptr;
486
487 rcu_read_lock();
488 list_for_each_entry_rcu(n_ptr, &tn->node_list, list) {
489 tipc_node_lock(n_ptr);
490 l_ptr = n_ptr->links[bearer_id];
491 if (l_ptr)
492 tipc_link_reset(l_ptr);
493 tipc_node_unlock(n_ptr);
494 }
495 rcu_read_unlock();
496 }
497
498 static void link_activate(struct tipc_link *link)
499 {
500 struct tipc_node *node = link->owner;
501
502 link->next_in_no = 1;
503 link->stats.recv_info = 1;
504 tipc_node_link_up(node, link);
505 tipc_bearer_add_dest(node->net, link->bearer_id, link->addr);
506 }
507
508 /**
509 * link_state_event - link finite state machine
510 * @l_ptr: pointer to link
511 * @event: state machine event to process
512 */
513 static void link_state_event(struct tipc_link *l_ptr, unsigned int event)
514 {
515 struct tipc_link *other;
516 unsigned long cont_intv = l_ptr->cont_intv;
517
518 if (l_ptr->flags & LINK_STOPPED)
519 return;
520
521 if (!(l_ptr->flags & LINK_STARTED) && (event != STARTING_EVT))
522 return; /* Not yet. */
523
524 /* Check whether changeover is going on */
525 if (l_ptr->exp_msg_count) {
526 if (event == TIMEOUT_EVT)
527 link_set_timer(l_ptr, cont_intv);
528 return;
529 }
530
531 switch (l_ptr->state) {
532 case WORKING_WORKING:
533 switch (event) {
534 case TRAFFIC_MSG_EVT:
535 case ACTIVATE_MSG:
536 break;
537 case TIMEOUT_EVT:
538 if (l_ptr->next_in_no != l_ptr->checkpoint) {
539 l_ptr->checkpoint = l_ptr->next_in_no;
540 if (tipc_bclink_acks_missing(l_ptr->owner)) {
541 tipc_link_proto_xmit(l_ptr, STATE_MSG,
542 0, 0, 0, 0, 0);
543 l_ptr->fsm_msg_cnt++;
544 } else if (l_ptr->max_pkt < l_ptr->max_pkt_target) {
545 tipc_link_proto_xmit(l_ptr, STATE_MSG,
546 1, 0, 0, 0, 0);
547 l_ptr->fsm_msg_cnt++;
548 }
549 link_set_timer(l_ptr, cont_intv);
550 break;
551 }
552 l_ptr->state = WORKING_UNKNOWN;
553 l_ptr->fsm_msg_cnt = 0;
554 tipc_link_proto_xmit(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
555 l_ptr->fsm_msg_cnt++;
556 link_set_timer(l_ptr, cont_intv / 4);
557 break;
558 case RESET_MSG:
559 pr_debug("%s<%s>, requested by peer\n",
560 link_rst_msg, l_ptr->name);
561 tipc_link_reset(l_ptr);
562 l_ptr->state = RESET_RESET;
563 l_ptr->fsm_msg_cnt = 0;
564 tipc_link_proto_xmit(l_ptr, ACTIVATE_MSG,
565 0, 0, 0, 0, 0);
566 l_ptr->fsm_msg_cnt++;
567 link_set_timer(l_ptr, cont_intv);
568 break;
569 default:
570 pr_debug("%s%u in WW state\n", link_unk_evt, event);
571 }
572 break;
573 case WORKING_UNKNOWN:
574 switch (event) {
575 case TRAFFIC_MSG_EVT:
576 case ACTIVATE_MSG:
577 l_ptr->state = WORKING_WORKING;
578 l_ptr->fsm_msg_cnt = 0;
579 link_set_timer(l_ptr, cont_intv);
580 break;
581 case RESET_MSG:
582 pr_debug("%s<%s>, requested by peer while probing\n",
583 link_rst_msg, l_ptr->name);
584 tipc_link_reset(l_ptr);
585 l_ptr->state = RESET_RESET;
586 l_ptr->fsm_msg_cnt = 0;
587 tipc_link_proto_xmit(l_ptr, ACTIVATE_MSG,
588 0, 0, 0, 0, 0);
589 l_ptr->fsm_msg_cnt++;
590 link_set_timer(l_ptr, cont_intv);
591 break;
592 case TIMEOUT_EVT:
593 if (l_ptr->next_in_no != l_ptr->checkpoint) {
594 l_ptr->state = WORKING_WORKING;
595 l_ptr->fsm_msg_cnt = 0;
596 l_ptr->checkpoint = l_ptr->next_in_no;
597 if (tipc_bclink_acks_missing(l_ptr->owner)) {
598 tipc_link_proto_xmit(l_ptr, STATE_MSG,
599 0, 0, 0, 0, 0);
600 l_ptr->fsm_msg_cnt++;
601 }
602 link_set_timer(l_ptr, cont_intv);
603 } else if (l_ptr->fsm_msg_cnt < l_ptr->abort_limit) {
604 tipc_link_proto_xmit(l_ptr, STATE_MSG,
605 1, 0, 0, 0, 0);
606 l_ptr->fsm_msg_cnt++;
607 link_set_timer(l_ptr, cont_intv / 4);
608 } else { /* Link has failed */
609 pr_debug("%s<%s>, peer not responding\n",
610 link_rst_msg, l_ptr->name);
611 tipc_link_reset(l_ptr);
612 l_ptr->state = RESET_UNKNOWN;
613 l_ptr->fsm_msg_cnt = 0;
614 tipc_link_proto_xmit(l_ptr, RESET_MSG,
615 0, 0, 0, 0, 0);
616 l_ptr->fsm_msg_cnt++;
617 link_set_timer(l_ptr, cont_intv);
618 }
619 break;
620 default:
621 pr_err("%s%u in WU state\n", link_unk_evt, event);
622 }
623 break;
624 case RESET_UNKNOWN:
625 switch (event) {
626 case TRAFFIC_MSG_EVT:
627 break;
628 case ACTIVATE_MSG:
629 other = l_ptr->owner->active_links[0];
630 if (other && link_working_unknown(other))
631 break;
632 l_ptr->state = WORKING_WORKING;
633 l_ptr->fsm_msg_cnt = 0;
634 link_activate(l_ptr);
635 tipc_link_proto_xmit(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
636 l_ptr->fsm_msg_cnt++;
637 if (l_ptr->owner->working_links == 1)
638 tipc_link_sync_xmit(l_ptr);
639 link_set_timer(l_ptr, cont_intv);
640 break;
641 case RESET_MSG:
642 l_ptr->state = RESET_RESET;
643 l_ptr->fsm_msg_cnt = 0;
644 tipc_link_proto_xmit(l_ptr, ACTIVATE_MSG,
645 1, 0, 0, 0, 0);
646 l_ptr->fsm_msg_cnt++;
647 link_set_timer(l_ptr, cont_intv);
648 break;
649 case STARTING_EVT:
650 l_ptr->flags |= LINK_STARTED;
651 l_ptr->fsm_msg_cnt++;
652 link_set_timer(l_ptr, cont_intv);
653 break;
654 case TIMEOUT_EVT:
655 tipc_link_proto_xmit(l_ptr, RESET_MSG, 0, 0, 0, 0, 0);
656 l_ptr->fsm_msg_cnt++;
657 link_set_timer(l_ptr, cont_intv);
658 break;
659 default:
660 pr_err("%s%u in RU state\n", link_unk_evt, event);
661 }
662 break;
663 case RESET_RESET:
664 switch (event) {
665 case TRAFFIC_MSG_EVT:
666 case ACTIVATE_MSG:
667 other = l_ptr->owner->active_links[0];
668 if (other && link_working_unknown(other))
669 break;
670 l_ptr->state = WORKING_WORKING;
671 l_ptr->fsm_msg_cnt = 0;
672 link_activate(l_ptr);
673 tipc_link_proto_xmit(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
674 l_ptr->fsm_msg_cnt++;
675 if (l_ptr->owner->working_links == 1)
676 tipc_link_sync_xmit(l_ptr);
677 link_set_timer(l_ptr, cont_intv);
678 break;
679 case RESET_MSG:
680 break;
681 case TIMEOUT_EVT:
682 tipc_link_proto_xmit(l_ptr, ACTIVATE_MSG,
683 0, 0, 0, 0, 0);
684 l_ptr->fsm_msg_cnt++;
685 link_set_timer(l_ptr, cont_intv);
686 break;
687 default:
688 pr_err("%s%u in RR state\n", link_unk_evt, event);
689 }
690 break;
691 default:
692 pr_err("Unknown link state %u/%u\n", l_ptr->state, event);
693 }
694 }
695
696 /* tipc_link_cong: determine return value and how to treat the
697 * sent buffer during link congestion.
698 * - For plain, errorless user data messages we keep the buffer and
699 * return -ELINKONG.
700 * - For all other messages we discard the buffer and return -EHOSTUNREACH
701 * - For TIPC internal messages we also reset the link
702 */
703 static int tipc_link_cong(struct tipc_link *link, struct sk_buff_head *list)
704 {
705 struct sk_buff *skb = skb_peek(list);
706 struct tipc_msg *msg = buf_msg(skb);
707 uint imp = tipc_msg_tot_importance(msg);
708 u32 oport = msg_tot_origport(msg);
709
710 if (unlikely(imp > TIPC_CRITICAL_IMPORTANCE)) {
711 pr_warn("%s<%s>, send queue full", link_rst_msg, link->name);
712 tipc_link_reset(link);
713 goto drop;
714 }
715 if (unlikely(msg_errcode(msg)))
716 goto drop;
717 if (unlikely(msg_reroute_cnt(msg)))
718 goto drop;
719 if (TIPC_SKB_CB(skb)->wakeup_pending)
720 return -ELINKCONG;
721 if (link_schedule_user(link, oport, skb_queue_len(list), imp))
722 return -ELINKCONG;
723 drop:
724 __skb_queue_purge(list);
725 return -EHOSTUNREACH;
726 }
727
728 /**
729 * __tipc_link_xmit(): same as tipc_link_xmit, but destlink is known & locked
730 * @link: link to use
731 * @list: chain of buffers containing message
732 *
733 * Consumes the buffer chain, except when returning -ELINKCONG
734 * Returns 0 if success, otherwise errno: -ELINKCONG, -EMSGSIZE (plain socket
735 * user data messages) or -EHOSTUNREACH (all other messages/senders)
736 * Only the socket functions tipc_send_stream() and tipc_send_packet() need
737 * to act on the return value, since they may need to do more send attempts.
738 */
739 int __tipc_link_xmit(struct net *net, struct tipc_link *link,
740 struct sk_buff_head *list)
741 {
742 struct tipc_msg *msg = buf_msg(skb_peek(list));
743 uint psz = msg_size(msg);
744 uint sndlim = link->queue_limit[0];
745 uint imp = tipc_msg_tot_importance(msg);
746 uint mtu = link->max_pkt;
747 uint ack = mod(link->next_in_no - 1);
748 uint seqno = link->next_out_no;
749 uint bc_last_in = link->owner->bclink.last_in;
750 struct tipc_media_addr *addr = &link->media_addr;
751 struct sk_buff_head *outqueue = &link->outqueue;
752 struct sk_buff *skb, *tmp;
753
754 /* Match queue limits against msg importance: */
755 if (unlikely(skb_queue_len(outqueue) >= link->queue_limit[imp]))
756 return tipc_link_cong(link, list);
757
758 /* Has valid packet limit been used ? */
759 if (unlikely(psz > mtu)) {
760 __skb_queue_purge(list);
761 return -EMSGSIZE;
762 }
763
764 /* Prepare each packet for sending, and add to outqueue: */
765 skb_queue_walk_safe(list, skb, tmp) {
766 __skb_unlink(skb, list);
767 msg = buf_msg(skb);
768 msg_set_word(msg, 2, ((ack << 16) | mod(seqno)));
769 msg_set_bcast_ack(msg, bc_last_in);
770
771 if (skb_queue_len(outqueue) < sndlim) {
772 __skb_queue_tail(outqueue, skb);
773 tipc_bearer_send(net, link->bearer_id,
774 skb, addr);
775 link->next_out = NULL;
776 link->unacked_window = 0;
777 } else if (tipc_msg_bundle(outqueue, skb, mtu)) {
778 link->stats.sent_bundled++;
779 continue;
780 } else if (tipc_msg_make_bundle(outqueue, skb, mtu,
781 link->addr)) {
782 link->stats.sent_bundled++;
783 link->stats.sent_bundles++;
784 if (!link->next_out)
785 link->next_out = skb_peek_tail(outqueue);
786 } else {
787 __skb_queue_tail(outqueue, skb);
788 if (!link->next_out)
789 link->next_out = skb;
790 }
791 seqno++;
792 }
793 link->next_out_no = seqno;
794 return 0;
795 }
796
797 static void skb2list(struct sk_buff *skb, struct sk_buff_head *list)
798 {
799 skb_queue_head_init(list);
800 __skb_queue_tail(list, skb);
801 }
802
803 static int __tipc_link_xmit_skb(struct tipc_link *link, struct sk_buff *skb)
804 {
805 struct sk_buff_head head;
806
807 skb2list(skb, &head);
808 return __tipc_link_xmit(link->owner->net, link, &head);
809 }
810
811 int tipc_link_xmit_skb(struct net *net, struct sk_buff *skb, u32 dnode,
812 u32 selector)
813 {
814 struct sk_buff_head head;
815
816 skb2list(skb, &head);
817 return tipc_link_xmit(net, &head, dnode, selector);
818 }
819
820 /**
821 * tipc_link_xmit() is the general link level function for message sending
822 * @net: the applicable net namespace
823 * @list: chain of buffers containing message
824 * @dsz: amount of user data to be sent
825 * @dnode: address of destination node
826 * @selector: a number used for deterministic link selection
827 * Consumes the buffer chain, except when returning -ELINKCONG
828 * Returns 0 if success, otherwise errno: -ELINKCONG,-EHOSTUNREACH,-EMSGSIZE
829 */
830 int tipc_link_xmit(struct net *net, struct sk_buff_head *list, u32 dnode,
831 u32 selector)
832 {
833 struct tipc_link *link = NULL;
834 struct tipc_node *node;
835 int rc = -EHOSTUNREACH;
836
837 node = tipc_node_find(net, dnode);
838 if (node) {
839 tipc_node_lock(node);
840 link = node->active_links[selector & 1];
841 if (link)
842 rc = __tipc_link_xmit(net, link, list);
843 tipc_node_unlock(node);
844 }
845 if (link)
846 return rc;
847
848 if (likely(in_own_node(net, dnode)))
849 return tipc_sk_rcv(net, list);
850
851 __skb_queue_purge(list);
852 return rc;
853 }
854
855 /*
856 * tipc_link_sync_xmit - synchronize broadcast link endpoints.
857 *
858 * Give a newly added peer node the sequence number where it should
859 * start receiving and acking broadcast packets.
860 *
861 * Called with node locked
862 */
863 static void tipc_link_sync_xmit(struct tipc_link *link)
864 {
865 struct sk_buff *skb;
866 struct tipc_msg *msg;
867
868 skb = tipc_buf_acquire(INT_H_SIZE);
869 if (!skb)
870 return;
871
872 msg = buf_msg(skb);
873 tipc_msg_init(link_own_addr(link), msg, BCAST_PROTOCOL, STATE_MSG,
874 INT_H_SIZE, link->addr);
875 msg_set_last_bcast(msg, link->owner->bclink.acked);
876 __tipc_link_xmit_skb(link, skb);
877 }
878
879 /*
880 * tipc_link_sync_rcv - synchronize broadcast link endpoints.
881 * Receive the sequence number where we should start receiving and
882 * acking broadcast packets from a newly added peer node, and open
883 * up for reception of such packets.
884 *
885 * Called with node locked
886 */
887 static void tipc_link_sync_rcv(struct tipc_node *n, struct sk_buff *buf)
888 {
889 struct tipc_msg *msg = buf_msg(buf);
890
891 n->bclink.last_sent = n->bclink.last_in = msg_last_bcast(msg);
892 n->bclink.recv_permitted = true;
893 kfree_skb(buf);
894 }
895
896 struct sk_buff *tipc_skb_queue_next(const struct sk_buff_head *list,
897 const struct sk_buff *skb)
898 {
899 if (skb_queue_is_last(list, skb))
900 return NULL;
901 return skb->next;
902 }
903
904 /*
905 * tipc_link_push_packets - push unsent packets to bearer
906 *
907 * Push out the unsent messages of a link where congestion
908 * has abated. Node is locked.
909 *
910 * Called with node locked
911 */
912 void tipc_link_push_packets(struct tipc_link *l_ptr)
913 {
914 struct sk_buff_head *outqueue = &l_ptr->outqueue;
915 struct sk_buff *skb = l_ptr->next_out;
916 struct tipc_msg *msg;
917 u32 next, first;
918
919 skb_queue_walk_from(outqueue, skb) {
920 msg = buf_msg(skb);
921 next = msg_seqno(msg);
922 first = buf_seqno(skb_peek(outqueue));
923
924 if (mod(next - first) < l_ptr->queue_limit[0]) {
925 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
926 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
927 if (msg_user(msg) == MSG_BUNDLER)
928 TIPC_SKB_CB(skb)->bundling = false;
929 tipc_bearer_send(l_ptr->owner->net,
930 l_ptr->bearer_id, skb,
931 &l_ptr->media_addr);
932 l_ptr->next_out = tipc_skb_queue_next(outqueue, skb);
933 } else {
934 break;
935 }
936 }
937 }
938
939 void tipc_link_reset_all(struct tipc_node *node)
940 {
941 char addr_string[16];
942 u32 i;
943
944 tipc_node_lock(node);
945
946 pr_warn("Resetting all links to %s\n",
947 tipc_addr_string_fill(addr_string, node->addr));
948
949 for (i = 0; i < MAX_BEARERS; i++) {
950 if (node->links[i]) {
951 link_print(node->links[i], "Resetting link\n");
952 tipc_link_reset(node->links[i]);
953 }
954 }
955
956 tipc_node_unlock(node);
957 }
958
959 static void link_retransmit_failure(struct tipc_link *l_ptr,
960 struct sk_buff *buf)
961 {
962 struct tipc_msg *msg = buf_msg(buf);
963 struct net *net = l_ptr->owner->net;
964
965 pr_warn("Retransmission failure on link <%s>\n", l_ptr->name);
966
967 if (l_ptr->addr) {
968 /* Handle failure on standard link */
969 link_print(l_ptr, "Resetting link\n");
970 tipc_link_reset(l_ptr);
971
972 } else {
973 /* Handle failure on broadcast link */
974 struct tipc_node *n_ptr;
975 char addr_string[16];
976
977 pr_info("Msg seq number: %u, ", msg_seqno(msg));
978 pr_cont("Outstanding acks: %lu\n",
979 (unsigned long) TIPC_SKB_CB(buf)->handle);
980
981 n_ptr = tipc_bclink_retransmit_to(net);
982 tipc_node_lock(n_ptr);
983
984 tipc_addr_string_fill(addr_string, n_ptr->addr);
985 pr_info("Broadcast link info for %s\n", addr_string);
986 pr_info("Reception permitted: %d, Acked: %u\n",
987 n_ptr->bclink.recv_permitted,
988 n_ptr->bclink.acked);
989 pr_info("Last in: %u, Oos state: %u, Last sent: %u\n",
990 n_ptr->bclink.last_in,
991 n_ptr->bclink.oos_state,
992 n_ptr->bclink.last_sent);
993
994 tipc_node_unlock(n_ptr);
995
996 tipc_bclink_set_flags(net, TIPC_BCLINK_RESET);
997 l_ptr->stale_count = 0;
998 }
999 }
1000
1001 void tipc_link_retransmit(struct tipc_link *l_ptr, struct sk_buff *skb,
1002 u32 retransmits)
1003 {
1004 struct tipc_msg *msg;
1005
1006 if (!skb)
1007 return;
1008
1009 msg = buf_msg(skb);
1010
1011 /* Detect repeated retransmit failures */
1012 if (l_ptr->last_retransmitted == msg_seqno(msg)) {
1013 if (++l_ptr->stale_count > 100) {
1014 link_retransmit_failure(l_ptr, skb);
1015 return;
1016 }
1017 } else {
1018 l_ptr->last_retransmitted = msg_seqno(msg);
1019 l_ptr->stale_count = 1;
1020 }
1021
1022 skb_queue_walk_from(&l_ptr->outqueue, skb) {
1023 if (!retransmits || skb == l_ptr->next_out)
1024 break;
1025 msg = buf_msg(skb);
1026 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
1027 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1028 tipc_bearer_send(l_ptr->owner->net, l_ptr->bearer_id, skb,
1029 &l_ptr->media_addr);
1030 retransmits--;
1031 l_ptr->stats.retransmitted++;
1032 }
1033 }
1034
1035 static void link_retrieve_defq(struct tipc_link *link,
1036 struct sk_buff_head *list)
1037 {
1038 u32 seq_no;
1039
1040 if (skb_queue_empty(&link->deferred_queue))
1041 return;
1042
1043 seq_no = buf_seqno(skb_peek(&link->deferred_queue));
1044 if (seq_no == mod(link->next_in_no))
1045 skb_queue_splice_tail_init(&link->deferred_queue, list);
1046 }
1047
1048 /**
1049 * link_recv_buf_validate - validate basic format of received message
1050 *
1051 * This routine ensures a TIPC message has an acceptable header, and at least
1052 * as much data as the header indicates it should. The routine also ensures
1053 * that the entire message header is stored in the main fragment of the message
1054 * buffer, to simplify future access to message header fields.
1055 *
1056 * Note: Having extra info present in the message header or data areas is OK.
1057 * TIPC will ignore the excess, under the assumption that it is optional info
1058 * introduced by a later release of the protocol.
1059 */
1060 static int link_recv_buf_validate(struct sk_buff *buf)
1061 {
1062 static u32 min_data_hdr_size[8] = {
1063 SHORT_H_SIZE, MCAST_H_SIZE, NAMED_H_SIZE, BASIC_H_SIZE,
1064 MAX_H_SIZE, MAX_H_SIZE, MAX_H_SIZE, MAX_H_SIZE
1065 };
1066
1067 struct tipc_msg *msg;
1068 u32 tipc_hdr[2];
1069 u32 size;
1070 u32 hdr_size;
1071 u32 min_hdr_size;
1072
1073 /* If this packet comes from the defer queue, the skb has already
1074 * been validated
1075 */
1076 if (unlikely(TIPC_SKB_CB(buf)->deferred))
1077 return 1;
1078
1079 if (unlikely(buf->len < MIN_H_SIZE))
1080 return 0;
1081
1082 msg = skb_header_pointer(buf, 0, sizeof(tipc_hdr), tipc_hdr);
1083 if (msg == NULL)
1084 return 0;
1085
1086 if (unlikely(msg_version(msg) != TIPC_VERSION))
1087 return 0;
1088
1089 size = msg_size(msg);
1090 hdr_size = msg_hdr_sz(msg);
1091 min_hdr_size = msg_isdata(msg) ?
1092 min_data_hdr_size[msg_type(msg)] : INT_H_SIZE;
1093
1094 if (unlikely((hdr_size < min_hdr_size) ||
1095 (size < hdr_size) ||
1096 (buf->len < size) ||
1097 (size - hdr_size > TIPC_MAX_USER_MSG_SIZE)))
1098 return 0;
1099
1100 return pskb_may_pull(buf, hdr_size);
1101 }
1102
1103 /**
1104 * tipc_rcv - process TIPC packets/messages arriving from off-node
1105 * @net: the applicable net namespace
1106 * @skb: TIPC packet
1107 * @b_ptr: pointer to bearer message arrived on
1108 *
1109 * Invoked with no locks held. Bearer pointer must point to a valid bearer
1110 * structure (i.e. cannot be NULL), but bearer can be inactive.
1111 */
1112 void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b_ptr)
1113 {
1114 struct tipc_net *tn = net_generic(net, tipc_net_id);
1115 struct sk_buff_head head;
1116 struct tipc_node *n_ptr;
1117 struct tipc_link *l_ptr;
1118 struct sk_buff *skb1, *tmp;
1119 struct tipc_msg *msg;
1120 u32 seq_no;
1121 u32 ackd;
1122 u32 released;
1123
1124 skb2list(skb, &head);
1125
1126 while ((skb = __skb_dequeue(&head))) {
1127 /* Ensure message is well-formed */
1128 if (unlikely(!link_recv_buf_validate(skb)))
1129 goto discard;
1130
1131 /* Ensure message data is a single contiguous unit */
1132 if (unlikely(skb_linearize(skb)))
1133 goto discard;
1134
1135 /* Handle arrival of a non-unicast link message */
1136 msg = buf_msg(skb);
1137
1138 if (unlikely(msg_non_seq(msg))) {
1139 if (msg_user(msg) == LINK_CONFIG)
1140 tipc_disc_rcv(net, skb, b_ptr);
1141 else
1142 tipc_bclink_rcv(net, skb);
1143 continue;
1144 }
1145
1146 /* Discard unicast link messages destined for another node */
1147 if (unlikely(!msg_short(msg) &&
1148 (msg_destnode(msg) != tn->own_addr)))
1149 goto discard;
1150
1151 /* Locate neighboring node that sent message */
1152 n_ptr = tipc_node_find(net, msg_prevnode(msg));
1153 if (unlikely(!n_ptr))
1154 goto discard;
1155 tipc_node_lock(n_ptr);
1156
1157 /* Locate unicast link endpoint that should handle message */
1158 l_ptr = n_ptr->links[b_ptr->identity];
1159 if (unlikely(!l_ptr))
1160 goto unlock;
1161
1162 /* Verify that communication with node is currently allowed */
1163 if ((n_ptr->action_flags & TIPC_WAIT_PEER_LINKS_DOWN) &&
1164 msg_user(msg) == LINK_PROTOCOL &&
1165 (msg_type(msg) == RESET_MSG ||
1166 msg_type(msg) == ACTIVATE_MSG) &&
1167 !msg_redundant_link(msg))
1168 n_ptr->action_flags &= ~TIPC_WAIT_PEER_LINKS_DOWN;
1169
1170 if (tipc_node_blocked(n_ptr))
1171 goto unlock;
1172
1173 /* Validate message sequence number info */
1174 seq_no = msg_seqno(msg);
1175 ackd = msg_ack(msg);
1176
1177 /* Release acked messages */
1178 if (n_ptr->bclink.recv_permitted)
1179 tipc_bclink_acknowledge(n_ptr, msg_bcast_ack(msg));
1180
1181 released = 0;
1182 skb_queue_walk_safe(&l_ptr->outqueue, skb1, tmp) {
1183 if (skb1 == l_ptr->next_out ||
1184 more(buf_seqno(skb1), ackd))
1185 break;
1186 __skb_unlink(skb1, &l_ptr->outqueue);
1187 kfree_skb(skb1);
1188 released = 1;
1189 }
1190
1191 /* Try sending any messages link endpoint has pending */
1192 if (unlikely(l_ptr->next_out))
1193 tipc_link_push_packets(l_ptr);
1194
1195 if (released && !skb_queue_empty(&l_ptr->wakeupq))
1196 link_prepare_wakeup(l_ptr);
1197
1198 /* Process the incoming packet */
1199 if (unlikely(!link_working_working(l_ptr))) {
1200 if (msg_user(msg) == LINK_PROTOCOL) {
1201 tipc_link_proto_rcv(l_ptr, skb);
1202 link_retrieve_defq(l_ptr, &head);
1203 skb = NULL;
1204 goto unlock;
1205 }
1206
1207 /* Traffic message. Conditionally activate link */
1208 link_state_event(l_ptr, TRAFFIC_MSG_EVT);
1209
1210 if (link_working_working(l_ptr)) {
1211 /* Re-insert buffer in front of queue */
1212 __skb_queue_head(&head, skb);
1213 skb = NULL;
1214 goto unlock;
1215 }
1216 goto unlock;
1217 }
1218
1219 /* Link is now in state WORKING_WORKING */
1220 if (unlikely(seq_no != mod(l_ptr->next_in_no))) {
1221 link_handle_out_of_seq_msg(l_ptr, skb);
1222 link_retrieve_defq(l_ptr, &head);
1223 skb = NULL;
1224 goto unlock;
1225 }
1226 l_ptr->next_in_no++;
1227 if (unlikely(!skb_queue_empty(&l_ptr->deferred_queue)))
1228 link_retrieve_defq(l_ptr, &head);
1229
1230 if (unlikely(++l_ptr->unacked_window >= TIPC_MIN_LINK_WIN)) {
1231 l_ptr->stats.sent_acks++;
1232 tipc_link_proto_xmit(l_ptr, STATE_MSG, 0, 0, 0, 0, 0);
1233 }
1234 tipc_link_input(l_ptr, skb);
1235 skb = NULL;
1236 unlock:
1237 tipc_node_unlock(n_ptr);
1238 discard:
1239 if (unlikely(skb))
1240 kfree_skb(skb);
1241 }
1242 }
1243
1244 /* tipc_data_input - deliver data and name distr msgs to upper layer
1245 *
1246 * Consumes buffer if message is of right type
1247 * Node lock must be held
1248 */
1249 static bool tipc_data_input(struct tipc_link *link, struct sk_buff *skb)
1250 {
1251 struct tipc_node *node = link->owner;
1252 struct tipc_msg *msg = buf_msg(skb);
1253 u32 dport = msg_destport(msg);
1254
1255 switch (msg_user(msg)) {
1256 case TIPC_LOW_IMPORTANCE:
1257 case TIPC_MEDIUM_IMPORTANCE:
1258 case TIPC_HIGH_IMPORTANCE:
1259 case TIPC_CRITICAL_IMPORTANCE:
1260 case CONN_MANAGER:
1261 if (tipc_skb_queue_tail(&link->inputq, skb, dport)) {
1262 node->inputq = &link->inputq;
1263 node->action_flags |= TIPC_MSG_EVT;
1264 }
1265 return true;
1266 case NAME_DISTRIBUTOR:
1267 node->bclink.recv_permitted = true;
1268 node->namedq = &link->namedq;
1269 skb_queue_tail(&link->namedq, skb);
1270 if (skb_queue_len(&link->namedq) == 1)
1271 node->action_flags |= TIPC_NAMED_MSG_EVT;
1272 return true;
1273 case MSG_BUNDLER:
1274 case CHANGEOVER_PROTOCOL:
1275 case MSG_FRAGMENTER:
1276 case BCAST_PROTOCOL:
1277 return false;
1278 default:
1279 pr_warn("Dropping received illegal msg type\n");
1280 kfree_skb(skb);
1281 return false;
1282 };
1283 }
1284
1285 /* tipc_link_input - process packet that has passed link protocol check
1286 *
1287 * Consumes buffer
1288 * Node lock must be held
1289 */
1290 static void tipc_link_input(struct tipc_link *link, struct sk_buff *skb)
1291 {
1292 struct tipc_node *node = link->owner;
1293 struct tipc_msg *msg = buf_msg(skb);
1294 struct sk_buff *iskb;
1295 int pos = 0;
1296
1297 if (likely(tipc_data_input(link, skb)))
1298 return;
1299
1300 switch (msg_user(msg)) {
1301 case CHANGEOVER_PROTOCOL:
1302 if (!tipc_link_tunnel_rcv(node, &skb))
1303 break;
1304 if (msg_user(buf_msg(skb)) != MSG_BUNDLER) {
1305 tipc_data_input(link, skb);
1306 break;
1307 }
1308 case MSG_BUNDLER:
1309 link->stats.recv_bundles++;
1310 link->stats.recv_bundled += msg_msgcnt(msg);
1311
1312 while (tipc_msg_extract(skb, &iskb, &pos))
1313 tipc_data_input(link, iskb);
1314 break;
1315 case MSG_FRAGMENTER:
1316 link->stats.recv_fragments++;
1317 if (tipc_buf_append(&link->reasm_buf, &skb)) {
1318 link->stats.recv_fragmented++;
1319 tipc_data_input(link, skb);
1320 } else if (!link->reasm_buf) {
1321 tipc_link_reset(link);
1322 }
1323 break;
1324 case BCAST_PROTOCOL:
1325 tipc_link_sync_rcv(node, skb);
1326 break;
1327 default:
1328 break;
1329 };
1330 }
1331
1332 /**
1333 * tipc_link_defer_pkt - Add out-of-sequence message to deferred reception queue
1334 *
1335 * Returns increase in queue length (i.e. 0 or 1)
1336 */
1337 u32 tipc_link_defer_pkt(struct sk_buff_head *list, struct sk_buff *skb)
1338 {
1339 struct sk_buff *skb1;
1340 u32 seq_no = buf_seqno(skb);
1341
1342 /* Empty queue ? */
1343 if (skb_queue_empty(list)) {
1344 __skb_queue_tail(list, skb);
1345 return 1;
1346 }
1347
1348 /* Last ? */
1349 if (less(buf_seqno(skb_peek_tail(list)), seq_no)) {
1350 __skb_queue_tail(list, skb);
1351 return 1;
1352 }
1353
1354 /* Locate insertion point in queue, then insert; discard if duplicate */
1355 skb_queue_walk(list, skb1) {
1356 u32 curr_seqno = buf_seqno(skb1);
1357
1358 if (seq_no == curr_seqno) {
1359 kfree_skb(skb);
1360 return 0;
1361 }
1362
1363 if (less(seq_no, curr_seqno))
1364 break;
1365 }
1366
1367 __skb_queue_before(list, skb1, skb);
1368 return 1;
1369 }
1370
1371 /*
1372 * link_handle_out_of_seq_msg - handle arrival of out-of-sequence packet
1373 */
1374 static void link_handle_out_of_seq_msg(struct tipc_link *l_ptr,
1375 struct sk_buff *buf)
1376 {
1377 u32 seq_no = buf_seqno(buf);
1378
1379 if (likely(msg_user(buf_msg(buf)) == LINK_PROTOCOL)) {
1380 tipc_link_proto_rcv(l_ptr, buf);
1381 return;
1382 }
1383
1384 /* Record OOS packet arrival (force mismatch on next timeout) */
1385 l_ptr->checkpoint--;
1386
1387 /*
1388 * Discard packet if a duplicate; otherwise add it to deferred queue
1389 * and notify peer of gap as per protocol specification
1390 */
1391 if (less(seq_no, mod(l_ptr->next_in_no))) {
1392 l_ptr->stats.duplicates++;
1393 kfree_skb(buf);
1394 return;
1395 }
1396
1397 if (tipc_link_defer_pkt(&l_ptr->deferred_queue, buf)) {
1398 l_ptr->stats.deferred_recv++;
1399 TIPC_SKB_CB(buf)->deferred = true;
1400 if ((skb_queue_len(&l_ptr->deferred_queue) % 16) == 1)
1401 tipc_link_proto_xmit(l_ptr, STATE_MSG, 0, 0, 0, 0, 0);
1402 } else {
1403 l_ptr->stats.duplicates++;
1404 }
1405 }
1406
1407 /*
1408 * Send protocol message to the other endpoint.
1409 */
1410 void tipc_link_proto_xmit(struct tipc_link *l_ptr, u32 msg_typ, int probe_msg,
1411 u32 gap, u32 tolerance, u32 priority, u32 ack_mtu)
1412 {
1413 struct sk_buff *buf = NULL;
1414 struct tipc_msg *msg = l_ptr->pmsg;
1415 u32 msg_size = sizeof(l_ptr->proto_msg);
1416 int r_flag;
1417
1418 /* Don't send protocol message during link changeover */
1419 if (l_ptr->exp_msg_count)
1420 return;
1421
1422 /* Abort non-RESET send if communication with node is prohibited */
1423 if ((tipc_node_blocked(l_ptr->owner)) && (msg_typ != RESET_MSG))
1424 return;
1425
1426 /* Create protocol message with "out-of-sequence" sequence number */
1427 msg_set_type(msg, msg_typ);
1428 msg_set_net_plane(msg, l_ptr->net_plane);
1429 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1430 msg_set_last_bcast(msg, tipc_bclink_get_last_sent(l_ptr->owner->net));
1431
1432 if (msg_typ == STATE_MSG) {
1433 u32 next_sent = mod(l_ptr->next_out_no);
1434
1435 if (!tipc_link_is_up(l_ptr))
1436 return;
1437 if (l_ptr->next_out)
1438 next_sent = buf_seqno(l_ptr->next_out);
1439 msg_set_next_sent(msg, next_sent);
1440 if (!skb_queue_empty(&l_ptr->deferred_queue)) {
1441 u32 rec = buf_seqno(skb_peek(&l_ptr->deferred_queue));
1442 gap = mod(rec - mod(l_ptr->next_in_no));
1443 }
1444 msg_set_seq_gap(msg, gap);
1445 if (gap)
1446 l_ptr->stats.sent_nacks++;
1447 msg_set_link_tolerance(msg, tolerance);
1448 msg_set_linkprio(msg, priority);
1449 msg_set_max_pkt(msg, ack_mtu);
1450 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
1451 msg_set_probe(msg, probe_msg != 0);
1452 if (probe_msg) {
1453 u32 mtu = l_ptr->max_pkt;
1454
1455 if ((mtu < l_ptr->max_pkt_target) &&
1456 link_working_working(l_ptr) &&
1457 l_ptr->fsm_msg_cnt) {
1458 msg_size = (mtu + (l_ptr->max_pkt_target - mtu)/2 + 2) & ~3;
1459 if (l_ptr->max_pkt_probes == 10) {
1460 l_ptr->max_pkt_target = (msg_size - 4);
1461 l_ptr->max_pkt_probes = 0;
1462 msg_size = (mtu + (l_ptr->max_pkt_target - mtu)/2 + 2) & ~3;
1463 }
1464 l_ptr->max_pkt_probes++;
1465 }
1466
1467 l_ptr->stats.sent_probes++;
1468 }
1469 l_ptr->stats.sent_states++;
1470 } else { /* RESET_MSG or ACTIVATE_MSG */
1471 msg_set_ack(msg, mod(l_ptr->reset_checkpoint - 1));
1472 msg_set_seq_gap(msg, 0);
1473 msg_set_next_sent(msg, 1);
1474 msg_set_probe(msg, 0);
1475 msg_set_link_tolerance(msg, l_ptr->tolerance);
1476 msg_set_linkprio(msg, l_ptr->priority);
1477 msg_set_max_pkt(msg, l_ptr->max_pkt_target);
1478 }
1479
1480 r_flag = (l_ptr->owner->working_links > tipc_link_is_up(l_ptr));
1481 msg_set_redundant_link(msg, r_flag);
1482 msg_set_linkprio(msg, l_ptr->priority);
1483 msg_set_size(msg, msg_size);
1484
1485 msg_set_seqno(msg, mod(l_ptr->next_out_no + (0xffff/2)));
1486
1487 buf = tipc_buf_acquire(msg_size);
1488 if (!buf)
1489 return;
1490
1491 skb_copy_to_linear_data(buf, msg, sizeof(l_ptr->proto_msg));
1492 buf->priority = TC_PRIO_CONTROL;
1493
1494 tipc_bearer_send(l_ptr->owner->net, l_ptr->bearer_id, buf,
1495 &l_ptr->media_addr);
1496 l_ptr->unacked_window = 0;
1497 kfree_skb(buf);
1498 }
1499
1500 /*
1501 * Receive protocol message :
1502 * Note that network plane id propagates through the network, and may
1503 * change at any time. The node with lowest address rules
1504 */
1505 static void tipc_link_proto_rcv(struct tipc_link *l_ptr,
1506 struct sk_buff *buf)
1507 {
1508 u32 rec_gap = 0;
1509 u32 max_pkt_info;
1510 u32 max_pkt_ack;
1511 u32 msg_tol;
1512 struct tipc_msg *msg = buf_msg(buf);
1513
1514 /* Discard protocol message during link changeover */
1515 if (l_ptr->exp_msg_count)
1516 goto exit;
1517
1518 if (l_ptr->net_plane != msg_net_plane(msg))
1519 if (link_own_addr(l_ptr) > msg_prevnode(msg))
1520 l_ptr->net_plane = msg_net_plane(msg);
1521
1522 switch (msg_type(msg)) {
1523
1524 case RESET_MSG:
1525 if (!link_working_unknown(l_ptr) &&
1526 (l_ptr->peer_session != INVALID_SESSION)) {
1527 if (less_eq(msg_session(msg), l_ptr->peer_session))
1528 break; /* duplicate or old reset: ignore */
1529 }
1530
1531 if (!msg_redundant_link(msg) && (link_working_working(l_ptr) ||
1532 link_working_unknown(l_ptr))) {
1533 /*
1534 * peer has lost contact -- don't allow peer's links
1535 * to reactivate before we recognize loss & clean up
1536 */
1537 l_ptr->owner->action_flags |= TIPC_WAIT_OWN_LINKS_DOWN;
1538 }
1539
1540 link_state_event(l_ptr, RESET_MSG);
1541
1542 /* fall thru' */
1543 case ACTIVATE_MSG:
1544 /* Update link settings according other endpoint's values */
1545 strcpy((strrchr(l_ptr->name, ':') + 1), (char *)msg_data(msg));
1546
1547 msg_tol = msg_link_tolerance(msg);
1548 if (msg_tol > l_ptr->tolerance)
1549 link_set_supervision_props(l_ptr, msg_tol);
1550
1551 if (msg_linkprio(msg) > l_ptr->priority)
1552 l_ptr->priority = msg_linkprio(msg);
1553
1554 max_pkt_info = msg_max_pkt(msg);
1555 if (max_pkt_info) {
1556 if (max_pkt_info < l_ptr->max_pkt_target)
1557 l_ptr->max_pkt_target = max_pkt_info;
1558 if (l_ptr->max_pkt > l_ptr->max_pkt_target)
1559 l_ptr->max_pkt = l_ptr->max_pkt_target;
1560 } else {
1561 l_ptr->max_pkt = l_ptr->max_pkt_target;
1562 }
1563
1564 /* Synchronize broadcast link info, if not done previously */
1565 if (!tipc_node_is_up(l_ptr->owner)) {
1566 l_ptr->owner->bclink.last_sent =
1567 l_ptr->owner->bclink.last_in =
1568 msg_last_bcast(msg);
1569 l_ptr->owner->bclink.oos_state = 0;
1570 }
1571
1572 l_ptr->peer_session = msg_session(msg);
1573 l_ptr->peer_bearer_id = msg_bearer_id(msg);
1574
1575 if (msg_type(msg) == ACTIVATE_MSG)
1576 link_state_event(l_ptr, ACTIVATE_MSG);
1577 break;
1578 case STATE_MSG:
1579
1580 msg_tol = msg_link_tolerance(msg);
1581 if (msg_tol)
1582 link_set_supervision_props(l_ptr, msg_tol);
1583
1584 if (msg_linkprio(msg) &&
1585 (msg_linkprio(msg) != l_ptr->priority)) {
1586 pr_debug("%s<%s>, priority change %u->%u\n",
1587 link_rst_msg, l_ptr->name,
1588 l_ptr->priority, msg_linkprio(msg));
1589 l_ptr->priority = msg_linkprio(msg);
1590 tipc_link_reset(l_ptr); /* Enforce change to take effect */
1591 break;
1592 }
1593
1594 /* Record reception; force mismatch at next timeout: */
1595 l_ptr->checkpoint--;
1596
1597 link_state_event(l_ptr, TRAFFIC_MSG_EVT);
1598 l_ptr->stats.recv_states++;
1599 if (link_reset_unknown(l_ptr))
1600 break;
1601
1602 if (less_eq(mod(l_ptr->next_in_no), msg_next_sent(msg))) {
1603 rec_gap = mod(msg_next_sent(msg) -
1604 mod(l_ptr->next_in_no));
1605 }
1606
1607 max_pkt_ack = msg_max_pkt(msg);
1608 if (max_pkt_ack > l_ptr->max_pkt) {
1609 l_ptr->max_pkt = max_pkt_ack;
1610 l_ptr->max_pkt_probes = 0;
1611 }
1612
1613 max_pkt_ack = 0;
1614 if (msg_probe(msg)) {
1615 l_ptr->stats.recv_probes++;
1616 if (msg_size(msg) > sizeof(l_ptr->proto_msg))
1617 max_pkt_ack = msg_size(msg);
1618 }
1619
1620 /* Protocol message before retransmits, reduce loss risk */
1621 if (l_ptr->owner->bclink.recv_permitted)
1622 tipc_bclink_update_link_state(l_ptr->owner,
1623 msg_last_bcast(msg));
1624
1625 if (rec_gap || (msg_probe(msg))) {
1626 tipc_link_proto_xmit(l_ptr, STATE_MSG, 0, rec_gap, 0,
1627 0, max_pkt_ack);
1628 }
1629 if (msg_seq_gap(msg)) {
1630 l_ptr->stats.recv_nacks++;
1631 tipc_link_retransmit(l_ptr, skb_peek(&l_ptr->outqueue),
1632 msg_seq_gap(msg));
1633 }
1634 break;
1635 }
1636 exit:
1637 kfree_skb(buf);
1638 }
1639
1640
1641 /* tipc_link_tunnel_xmit(): Tunnel one packet via a link belonging to
1642 * a different bearer. Owner node is locked.
1643 */
1644 static void tipc_link_tunnel_xmit(struct tipc_link *l_ptr,
1645 struct tipc_msg *tunnel_hdr,
1646 struct tipc_msg *msg,
1647 u32 selector)
1648 {
1649 struct tipc_link *tunnel;
1650 struct sk_buff *skb;
1651 u32 length = msg_size(msg);
1652
1653 tunnel = l_ptr->owner->active_links[selector & 1];
1654 if (!tipc_link_is_up(tunnel)) {
1655 pr_warn("%stunnel link no longer available\n", link_co_err);
1656 return;
1657 }
1658 msg_set_size(tunnel_hdr, length + INT_H_SIZE);
1659 skb = tipc_buf_acquire(length + INT_H_SIZE);
1660 if (!skb) {
1661 pr_warn("%sunable to send tunnel msg\n", link_co_err);
1662 return;
1663 }
1664 skb_copy_to_linear_data(skb, tunnel_hdr, INT_H_SIZE);
1665 skb_copy_to_linear_data_offset(skb, INT_H_SIZE, msg, length);
1666 __tipc_link_xmit_skb(tunnel, skb);
1667 }
1668
1669
1670 /* tipc_link_failover_send_queue(): A link has gone down, but a second
1671 * link is still active. We can do failover. Tunnel the failing link's
1672 * whole send queue via the remaining link. This way, we don't lose
1673 * any packets, and sequence order is preserved for subsequent traffic
1674 * sent over the remaining link. Owner node is locked.
1675 */
1676 void tipc_link_failover_send_queue(struct tipc_link *l_ptr)
1677 {
1678 u32 msgcount = skb_queue_len(&l_ptr->outqueue);
1679 struct tipc_link *tunnel = l_ptr->owner->active_links[0];
1680 struct tipc_msg tunnel_hdr;
1681 struct sk_buff *skb;
1682 int split_bundles;
1683
1684 if (!tunnel)
1685 return;
1686
1687 tipc_msg_init(link_own_addr(l_ptr), &tunnel_hdr, CHANGEOVER_PROTOCOL,
1688 ORIGINAL_MSG, INT_H_SIZE, l_ptr->addr);
1689 msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id);
1690 msg_set_msgcnt(&tunnel_hdr, msgcount);
1691
1692 if (skb_queue_empty(&l_ptr->outqueue)) {
1693 skb = tipc_buf_acquire(INT_H_SIZE);
1694 if (skb) {
1695 skb_copy_to_linear_data(skb, &tunnel_hdr, INT_H_SIZE);
1696 msg_set_size(&tunnel_hdr, INT_H_SIZE);
1697 __tipc_link_xmit_skb(tunnel, skb);
1698 } else {
1699 pr_warn("%sunable to send changeover msg\n",
1700 link_co_err);
1701 }
1702 return;
1703 }
1704
1705 split_bundles = (l_ptr->owner->active_links[0] !=
1706 l_ptr->owner->active_links[1]);
1707
1708 skb_queue_walk(&l_ptr->outqueue, skb) {
1709 struct tipc_msg *msg = buf_msg(skb);
1710
1711 if ((msg_user(msg) == MSG_BUNDLER) && split_bundles) {
1712 struct tipc_msg *m = msg_get_wrapped(msg);
1713 unchar *pos = (unchar *)m;
1714
1715 msgcount = msg_msgcnt(msg);
1716 while (msgcount--) {
1717 msg_set_seqno(m, msg_seqno(msg));
1718 tipc_link_tunnel_xmit(l_ptr, &tunnel_hdr, m,
1719 msg_link_selector(m));
1720 pos += align(msg_size(m));
1721 m = (struct tipc_msg *)pos;
1722 }
1723 } else {
1724 tipc_link_tunnel_xmit(l_ptr, &tunnel_hdr, msg,
1725 msg_link_selector(msg));
1726 }
1727 }
1728 }
1729
1730 /* tipc_link_dup_queue_xmit(): A second link has become active. Tunnel a
1731 * duplicate of the first link's send queue via the new link. This way, we
1732 * are guaranteed that currently queued packets from a socket are delivered
1733 * before future traffic from the same socket, even if this is using the
1734 * new link. The last arriving copy of each duplicate packet is dropped at
1735 * the receiving end by the regular protocol check, so packet cardinality
1736 * and sequence order is preserved per sender/receiver socket pair.
1737 * Owner node is locked.
1738 */
1739 void tipc_link_dup_queue_xmit(struct tipc_link *l_ptr,
1740 struct tipc_link *tunnel)
1741 {
1742 struct sk_buff *skb;
1743 struct tipc_msg tunnel_hdr;
1744
1745 tipc_msg_init(link_own_addr(l_ptr), &tunnel_hdr, CHANGEOVER_PROTOCOL,
1746 DUPLICATE_MSG, INT_H_SIZE, l_ptr->addr);
1747 msg_set_msgcnt(&tunnel_hdr, skb_queue_len(&l_ptr->outqueue));
1748 msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id);
1749 skb_queue_walk(&l_ptr->outqueue, skb) {
1750 struct sk_buff *outskb;
1751 struct tipc_msg *msg = buf_msg(skb);
1752 u32 length = msg_size(msg);
1753
1754 if (msg_user(msg) == MSG_BUNDLER)
1755 msg_set_type(msg, CLOSED_MSG);
1756 msg_set_ack(msg, mod(l_ptr->next_in_no - 1)); /* Update */
1757 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1758 msg_set_size(&tunnel_hdr, length + INT_H_SIZE);
1759 outskb = tipc_buf_acquire(length + INT_H_SIZE);
1760 if (outskb == NULL) {
1761 pr_warn("%sunable to send duplicate msg\n",
1762 link_co_err);
1763 return;
1764 }
1765 skb_copy_to_linear_data(outskb, &tunnel_hdr, INT_H_SIZE);
1766 skb_copy_to_linear_data_offset(outskb, INT_H_SIZE, skb->data,
1767 length);
1768 __tipc_link_xmit_skb(tunnel, outskb);
1769 if (!tipc_link_is_up(l_ptr))
1770 return;
1771 }
1772 }
1773
1774 /**
1775 * buf_extract - extracts embedded TIPC message from another message
1776 * @skb: encapsulating message buffer
1777 * @from_pos: offset to extract from
1778 *
1779 * Returns a new message buffer containing an embedded message. The
1780 * encapsulating buffer is left unchanged.
1781 */
1782 static struct sk_buff *buf_extract(struct sk_buff *skb, u32 from_pos)
1783 {
1784 struct tipc_msg *msg = (struct tipc_msg *)(skb->data + from_pos);
1785 u32 size = msg_size(msg);
1786 struct sk_buff *eb;
1787
1788 eb = tipc_buf_acquire(size);
1789 if (eb)
1790 skb_copy_to_linear_data(eb, msg, size);
1791 return eb;
1792 }
1793
1794 /* tipc_link_dup_rcv(): Receive a tunnelled DUPLICATE_MSG packet.
1795 * Owner node is locked.
1796 */
1797 static void tipc_link_dup_rcv(struct tipc_link *l_ptr,
1798 struct sk_buff *t_buf)
1799 {
1800 struct sk_buff *buf;
1801
1802 if (!tipc_link_is_up(l_ptr))
1803 return;
1804
1805 buf = buf_extract(t_buf, INT_H_SIZE);
1806 if (buf == NULL) {
1807 pr_warn("%sfailed to extract inner dup pkt\n", link_co_err);
1808 return;
1809 }
1810
1811 /* Add buffer to deferred queue, if applicable: */
1812 link_handle_out_of_seq_msg(l_ptr, buf);
1813 }
1814
1815 /* tipc_link_failover_rcv(): Receive a tunnelled ORIGINAL_MSG packet
1816 * Owner node is locked.
1817 */
1818 static struct sk_buff *tipc_link_failover_rcv(struct tipc_link *l_ptr,
1819 struct sk_buff *t_buf)
1820 {
1821 struct tipc_msg *t_msg = buf_msg(t_buf);
1822 struct sk_buff *buf = NULL;
1823 struct tipc_msg *msg;
1824
1825 if (tipc_link_is_up(l_ptr))
1826 tipc_link_reset(l_ptr);
1827
1828 /* First failover packet? */
1829 if (l_ptr->exp_msg_count == START_CHANGEOVER)
1830 l_ptr->exp_msg_count = msg_msgcnt(t_msg);
1831
1832 /* Should there be an inner packet? */
1833 if (l_ptr->exp_msg_count) {
1834 l_ptr->exp_msg_count--;
1835 buf = buf_extract(t_buf, INT_H_SIZE);
1836 if (buf == NULL) {
1837 pr_warn("%sno inner failover pkt\n", link_co_err);
1838 goto exit;
1839 }
1840 msg = buf_msg(buf);
1841
1842 if (less(msg_seqno(msg), l_ptr->reset_checkpoint)) {
1843 kfree_skb(buf);
1844 buf = NULL;
1845 goto exit;
1846 }
1847 if (msg_user(msg) == MSG_FRAGMENTER) {
1848 l_ptr->stats.recv_fragments++;
1849 tipc_buf_append(&l_ptr->reasm_buf, &buf);
1850 }
1851 }
1852 exit:
1853 if ((!l_ptr->exp_msg_count) && (l_ptr->flags & LINK_STOPPED))
1854 tipc_link_delete(l_ptr);
1855 return buf;
1856 }
1857
1858 /* tipc_link_tunnel_rcv(): Receive a tunnelled packet, sent
1859 * via other link as result of a failover (ORIGINAL_MSG) or
1860 * a new active link (DUPLICATE_MSG). Failover packets are
1861 * returned to the active link for delivery upwards.
1862 * Owner node is locked.
1863 */
1864 static int tipc_link_tunnel_rcv(struct tipc_node *n_ptr,
1865 struct sk_buff **buf)
1866 {
1867 struct sk_buff *t_buf = *buf;
1868 struct tipc_link *l_ptr;
1869 struct tipc_msg *t_msg = buf_msg(t_buf);
1870 u32 bearer_id = msg_bearer_id(t_msg);
1871
1872 *buf = NULL;
1873
1874 if (bearer_id >= MAX_BEARERS)
1875 goto exit;
1876
1877 l_ptr = n_ptr->links[bearer_id];
1878 if (!l_ptr)
1879 goto exit;
1880
1881 if (msg_type(t_msg) == DUPLICATE_MSG)
1882 tipc_link_dup_rcv(l_ptr, t_buf);
1883 else if (msg_type(t_msg) == ORIGINAL_MSG)
1884 *buf = tipc_link_failover_rcv(l_ptr, t_buf);
1885 else
1886 pr_warn("%sunknown tunnel pkt received\n", link_co_err);
1887 exit:
1888 kfree_skb(t_buf);
1889 return *buf != NULL;
1890 }
1891
1892 static void link_set_supervision_props(struct tipc_link *l_ptr, u32 tol)
1893 {
1894 unsigned long intv = ((tol / 4) > 500) ? 500 : tol / 4;
1895
1896 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
1897 return;
1898
1899 l_ptr->tolerance = tol;
1900 l_ptr->cont_intv = msecs_to_jiffies(intv);
1901 l_ptr->abort_limit = tol / (jiffies_to_msecs(l_ptr->cont_intv) / 4);
1902 }
1903
1904 void tipc_link_set_queue_limits(struct tipc_link *l_ptr, u32 window)
1905 {
1906 /* Data messages from this node, inclusive FIRST_FRAGM */
1907 l_ptr->queue_limit[TIPC_LOW_IMPORTANCE] = window;
1908 l_ptr->queue_limit[TIPC_MEDIUM_IMPORTANCE] = (window / 3) * 4;
1909 l_ptr->queue_limit[TIPC_HIGH_IMPORTANCE] = (window / 3) * 5;
1910 l_ptr->queue_limit[TIPC_CRITICAL_IMPORTANCE] = (window / 3) * 6;
1911 /* Transiting data messages,inclusive FIRST_FRAGM */
1912 l_ptr->queue_limit[TIPC_LOW_IMPORTANCE + 4] = 300;
1913 l_ptr->queue_limit[TIPC_MEDIUM_IMPORTANCE + 4] = 600;
1914 l_ptr->queue_limit[TIPC_HIGH_IMPORTANCE + 4] = 900;
1915 l_ptr->queue_limit[TIPC_CRITICAL_IMPORTANCE + 4] = 1200;
1916 l_ptr->queue_limit[CONN_MANAGER] = 1200;
1917 l_ptr->queue_limit[CHANGEOVER_PROTOCOL] = 2500;
1918 l_ptr->queue_limit[NAME_DISTRIBUTOR] = 3000;
1919 /* FRAGMENT and LAST_FRAGMENT packets */
1920 l_ptr->queue_limit[MSG_FRAGMENTER] = 4000;
1921 }
1922
1923 /* tipc_link_find_owner - locate owner node of link by link's name
1924 * @net: the applicable net namespace
1925 * @name: pointer to link name string
1926 * @bearer_id: pointer to index in 'node->links' array where the link was found.
1927 *
1928 * Returns pointer to node owning the link, or 0 if no matching link is found.
1929 */
1930 static struct tipc_node *tipc_link_find_owner(struct net *net,
1931 const char *link_name,
1932 unsigned int *bearer_id)
1933 {
1934 struct tipc_net *tn = net_generic(net, tipc_net_id);
1935 struct tipc_link *l_ptr;
1936 struct tipc_node *n_ptr;
1937 struct tipc_node *found_node = NULL;
1938 int i;
1939
1940 *bearer_id = 0;
1941 rcu_read_lock();
1942 list_for_each_entry_rcu(n_ptr, &tn->node_list, list) {
1943 tipc_node_lock(n_ptr);
1944 for (i = 0; i < MAX_BEARERS; i++) {
1945 l_ptr = n_ptr->links[i];
1946 if (l_ptr && !strcmp(l_ptr->name, link_name)) {
1947 *bearer_id = i;
1948 found_node = n_ptr;
1949 break;
1950 }
1951 }
1952 tipc_node_unlock(n_ptr);
1953 if (found_node)
1954 break;
1955 }
1956 rcu_read_unlock();
1957
1958 return found_node;
1959 }
1960
1961 /**
1962 * link_reset_statistics - reset link statistics
1963 * @l_ptr: pointer to link
1964 */
1965 static void link_reset_statistics(struct tipc_link *l_ptr)
1966 {
1967 memset(&l_ptr->stats, 0, sizeof(l_ptr->stats));
1968 l_ptr->stats.sent_info = l_ptr->next_out_no;
1969 l_ptr->stats.recv_info = l_ptr->next_in_no;
1970 }
1971
1972 static void link_print(struct tipc_link *l_ptr, const char *str)
1973 {
1974 struct tipc_net *tn = net_generic(l_ptr->owner->net, tipc_net_id);
1975 struct tipc_bearer *b_ptr;
1976
1977 rcu_read_lock();
1978 b_ptr = rcu_dereference_rtnl(tn->bearer_list[l_ptr->bearer_id]);
1979 if (b_ptr)
1980 pr_info("%s Link %x<%s>:", str, l_ptr->addr, b_ptr->name);
1981 rcu_read_unlock();
1982
1983 if (link_working_unknown(l_ptr))
1984 pr_cont(":WU\n");
1985 else if (link_reset_reset(l_ptr))
1986 pr_cont(":RR\n");
1987 else if (link_reset_unknown(l_ptr))
1988 pr_cont(":RU\n");
1989 else if (link_working_working(l_ptr))
1990 pr_cont(":WW\n");
1991 else
1992 pr_cont("\n");
1993 }
1994
1995 /* Parse and validate nested (link) properties valid for media, bearer and link
1996 */
1997 int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
1998 {
1999 int err;
2000
2001 err = nla_parse_nested(props, TIPC_NLA_PROP_MAX, prop,
2002 tipc_nl_prop_policy);
2003 if (err)
2004 return err;
2005
2006 if (props[TIPC_NLA_PROP_PRIO]) {
2007 u32 prio;
2008
2009 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
2010 if (prio > TIPC_MAX_LINK_PRI)
2011 return -EINVAL;
2012 }
2013
2014 if (props[TIPC_NLA_PROP_TOL]) {
2015 u32 tol;
2016
2017 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
2018 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
2019 return -EINVAL;
2020 }
2021
2022 if (props[TIPC_NLA_PROP_WIN]) {
2023 u32 win;
2024
2025 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
2026 if ((win < TIPC_MIN_LINK_WIN) || (win > TIPC_MAX_LINK_WIN))
2027 return -EINVAL;
2028 }
2029
2030 return 0;
2031 }
2032
2033 int tipc_nl_link_set(struct sk_buff *skb, struct genl_info *info)
2034 {
2035 int err;
2036 int res = 0;
2037 int bearer_id;
2038 char *name;
2039 struct tipc_link *link;
2040 struct tipc_node *node;
2041 struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2042 struct net *net = sock_net(skb->sk);
2043
2044 if (!info->attrs[TIPC_NLA_LINK])
2045 return -EINVAL;
2046
2047 err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX,
2048 info->attrs[TIPC_NLA_LINK],
2049 tipc_nl_link_policy);
2050 if (err)
2051 return err;
2052
2053 if (!attrs[TIPC_NLA_LINK_NAME])
2054 return -EINVAL;
2055
2056 name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2057
2058 node = tipc_link_find_owner(net, name, &bearer_id);
2059 if (!node)
2060 return -EINVAL;
2061
2062 tipc_node_lock(node);
2063
2064 link = node->links[bearer_id];
2065 if (!link) {
2066 res = -EINVAL;
2067 goto out;
2068 }
2069
2070 if (attrs[TIPC_NLA_LINK_PROP]) {
2071 struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
2072
2073 err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP],
2074 props);
2075 if (err) {
2076 res = err;
2077 goto out;
2078 }
2079
2080 if (props[TIPC_NLA_PROP_TOL]) {
2081 u32 tol;
2082
2083 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
2084 link_set_supervision_props(link, tol);
2085 tipc_link_proto_xmit(link, STATE_MSG, 0, 0, tol, 0, 0);
2086 }
2087 if (props[TIPC_NLA_PROP_PRIO]) {
2088 u32 prio;
2089
2090 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
2091 link->priority = prio;
2092 tipc_link_proto_xmit(link, STATE_MSG, 0, 0, 0, prio, 0);
2093 }
2094 if (props[TIPC_NLA_PROP_WIN]) {
2095 u32 win;
2096
2097 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
2098 tipc_link_set_queue_limits(link, win);
2099 }
2100 }
2101
2102 out:
2103 tipc_node_unlock(node);
2104
2105 return res;
2106 }
2107
2108 static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
2109 {
2110 int i;
2111 struct nlattr *stats;
2112
2113 struct nla_map {
2114 u32 key;
2115 u32 val;
2116 };
2117
2118 struct nla_map map[] = {
2119 {TIPC_NLA_STATS_RX_INFO, s->recv_info},
2120 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
2121 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
2122 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
2123 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
2124 {TIPC_NLA_STATS_TX_INFO, s->sent_info},
2125 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
2126 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
2127 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
2128 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
2129 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
2130 s->msg_length_counts : 1},
2131 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
2132 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
2133 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
2134 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
2135 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
2136 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
2137 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
2138 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
2139 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
2140 {TIPC_NLA_STATS_RX_STATES, s->recv_states},
2141 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
2142 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
2143 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
2144 {TIPC_NLA_STATS_TX_STATES, s->sent_states},
2145 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
2146 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
2147 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
2148 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
2149 {TIPC_NLA_STATS_DUPLICATES, s->duplicates},
2150 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
2151 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
2152 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
2153 (s->accu_queue_sz / s->queue_sz_counts) : 0}
2154 };
2155
2156 stats = nla_nest_start(skb, TIPC_NLA_LINK_STATS);
2157 if (!stats)
2158 return -EMSGSIZE;
2159
2160 for (i = 0; i < ARRAY_SIZE(map); i++)
2161 if (nla_put_u32(skb, map[i].key, map[i].val))
2162 goto msg_full;
2163
2164 nla_nest_end(skb, stats);
2165
2166 return 0;
2167 msg_full:
2168 nla_nest_cancel(skb, stats);
2169
2170 return -EMSGSIZE;
2171 }
2172
2173 /* Caller should hold appropriate locks to protect the link */
2174 static int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
2175 struct tipc_link *link)
2176 {
2177 int err;
2178 void *hdr;
2179 struct nlattr *attrs;
2180 struct nlattr *prop;
2181 struct tipc_net *tn = net_generic(net, tipc_net_id);
2182
2183 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2184 NLM_F_MULTI, TIPC_NL_LINK_GET);
2185 if (!hdr)
2186 return -EMSGSIZE;
2187
2188 attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK);
2189 if (!attrs)
2190 goto msg_full;
2191
2192 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
2193 goto attr_msg_full;
2194 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST,
2195 tipc_cluster_mask(tn->own_addr)))
2196 goto attr_msg_full;
2197 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->max_pkt))
2198 goto attr_msg_full;
2199 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->next_in_no))
2200 goto attr_msg_full;
2201 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->next_out_no))
2202 goto attr_msg_full;
2203
2204 if (tipc_link_is_up(link))
2205 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2206 goto attr_msg_full;
2207 if (tipc_link_is_active(link))
2208 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
2209 goto attr_msg_full;
2210
2211 prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP);
2212 if (!prop)
2213 goto attr_msg_full;
2214 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2215 goto prop_msg_full;
2216 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
2217 goto prop_msg_full;
2218 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
2219 link->queue_limit[TIPC_LOW_IMPORTANCE]))
2220 goto prop_msg_full;
2221 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2222 goto prop_msg_full;
2223 nla_nest_end(msg->skb, prop);
2224
2225 err = __tipc_nl_add_stats(msg->skb, &link->stats);
2226 if (err)
2227 goto attr_msg_full;
2228
2229 nla_nest_end(msg->skb, attrs);
2230 genlmsg_end(msg->skb, hdr);
2231
2232 return 0;
2233
2234 prop_msg_full:
2235 nla_nest_cancel(msg->skb, prop);
2236 attr_msg_full:
2237 nla_nest_cancel(msg->skb, attrs);
2238 msg_full:
2239 genlmsg_cancel(msg->skb, hdr);
2240
2241 return -EMSGSIZE;
2242 }
2243
2244 /* Caller should hold node lock */
2245 static int __tipc_nl_add_node_links(struct net *net, struct tipc_nl_msg *msg,
2246 struct tipc_node *node, u32 *prev_link)
2247 {
2248 u32 i;
2249 int err;
2250
2251 for (i = *prev_link; i < MAX_BEARERS; i++) {
2252 *prev_link = i;
2253
2254 if (!node->links[i])
2255 continue;
2256
2257 err = __tipc_nl_add_link(net, msg, node->links[i]);
2258 if (err)
2259 return err;
2260 }
2261 *prev_link = 0;
2262
2263 return 0;
2264 }
2265
2266 int tipc_nl_link_dump(struct sk_buff *skb, struct netlink_callback *cb)
2267 {
2268 struct net *net = sock_net(skb->sk);
2269 struct tipc_net *tn = net_generic(net, tipc_net_id);
2270 struct tipc_node *node;
2271 struct tipc_nl_msg msg;
2272 u32 prev_node = cb->args[0];
2273 u32 prev_link = cb->args[1];
2274 int done = cb->args[2];
2275 int err;
2276
2277 if (done)
2278 return 0;
2279
2280 msg.skb = skb;
2281 msg.portid = NETLINK_CB(cb->skb).portid;
2282 msg.seq = cb->nlh->nlmsg_seq;
2283
2284 rcu_read_lock();
2285
2286 if (prev_node) {
2287 node = tipc_node_find(net, prev_node);
2288 if (!node) {
2289 /* We never set seq or call nl_dump_check_consistent()
2290 * this means that setting prev_seq here will cause the
2291 * consistence check to fail in the netlink callback
2292 * handler. Resulting in the last NLMSG_DONE message
2293 * having the NLM_F_DUMP_INTR flag set.
2294 */
2295 cb->prev_seq = 1;
2296 goto out;
2297 }
2298
2299 list_for_each_entry_continue_rcu(node, &tn->node_list,
2300 list) {
2301 tipc_node_lock(node);
2302 err = __tipc_nl_add_node_links(net, &msg, node,
2303 &prev_link);
2304 tipc_node_unlock(node);
2305 if (err)
2306 goto out;
2307
2308 prev_node = node->addr;
2309 }
2310 } else {
2311 err = tipc_nl_add_bc_link(net, &msg);
2312 if (err)
2313 goto out;
2314
2315 list_for_each_entry_rcu(node, &tn->node_list, list) {
2316 tipc_node_lock(node);
2317 err = __tipc_nl_add_node_links(net, &msg, node,
2318 &prev_link);
2319 tipc_node_unlock(node);
2320 if (err)
2321 goto out;
2322
2323 prev_node = node->addr;
2324 }
2325 }
2326 done = 1;
2327 out:
2328 rcu_read_unlock();
2329
2330 cb->args[0] = prev_node;
2331 cb->args[1] = prev_link;
2332 cb->args[2] = done;
2333
2334 return skb->len;
2335 }
2336
2337 int tipc_nl_link_get(struct sk_buff *skb, struct genl_info *info)
2338 {
2339 struct net *net = genl_info_net(info);
2340 struct sk_buff *ans_skb;
2341 struct tipc_nl_msg msg;
2342 struct tipc_link *link;
2343 struct tipc_node *node;
2344 char *name;
2345 int bearer_id;
2346 int err;
2347
2348 if (!info->attrs[TIPC_NLA_LINK_NAME])
2349 return -EINVAL;
2350
2351 name = nla_data(info->attrs[TIPC_NLA_LINK_NAME]);
2352 node = tipc_link_find_owner(net, name, &bearer_id);
2353 if (!node)
2354 return -EINVAL;
2355
2356 ans_skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
2357 if (!ans_skb)
2358 return -ENOMEM;
2359
2360 msg.skb = ans_skb;
2361 msg.portid = info->snd_portid;
2362 msg.seq = info->snd_seq;
2363
2364 tipc_node_lock(node);
2365 link = node->links[bearer_id];
2366 if (!link) {
2367 err = -EINVAL;
2368 goto err_out;
2369 }
2370
2371 err = __tipc_nl_add_link(net, &msg, link);
2372 if (err)
2373 goto err_out;
2374
2375 tipc_node_unlock(node);
2376
2377 return genlmsg_reply(ans_skb, info);
2378
2379 err_out:
2380 tipc_node_unlock(node);
2381 nlmsg_free(ans_skb);
2382
2383 return err;
2384 }
2385
2386 int tipc_nl_link_reset_stats(struct sk_buff *skb, struct genl_info *info)
2387 {
2388 int err;
2389 char *link_name;
2390 unsigned int bearer_id;
2391 struct tipc_link *link;
2392 struct tipc_node *node;
2393 struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2394 struct net *net = sock_net(skb->sk);
2395
2396 if (!info->attrs[TIPC_NLA_LINK])
2397 return -EINVAL;
2398
2399 err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX,
2400 info->attrs[TIPC_NLA_LINK],
2401 tipc_nl_link_policy);
2402 if (err)
2403 return err;
2404
2405 if (!attrs[TIPC_NLA_LINK_NAME])
2406 return -EINVAL;
2407
2408 link_name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2409
2410 if (strcmp(link_name, tipc_bclink_name) == 0) {
2411 err = tipc_bclink_reset_stats(net);
2412 if (err)
2413 return err;
2414 return 0;
2415 }
2416
2417 node = tipc_link_find_owner(net, link_name, &bearer_id);
2418 if (!node)
2419 return -EINVAL;
2420
2421 tipc_node_lock(node);
2422
2423 link = node->links[bearer_id];
2424 if (!link) {
2425 tipc_node_unlock(node);
2426 return -EINVAL;
2427 }
2428
2429 link_reset_statistics(link);
2430
2431 tipc_node_unlock(node);
2432
2433 return 0;
2434 }
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