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Merge remote-tracking branches 'regulator/fix/da9211', 'regulator/fix/ltc3589' and...
[deliverable/linux.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 "port.h"
40 #include "socket.h"
41 #include "name_distr.h"
42 #include "discover.h"
43 #include "config.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 /*
55 * Out-of-range value for link session numbers
56 */
57 #define INVALID_SESSION 0x10000
58
59 /*
60 * Link state events:
61 */
62 #define STARTING_EVT 856384768 /* link processing trigger */
63 #define TRAFFIC_MSG_EVT 560815u /* rx'd ??? */
64 #define TIMEOUT_EVT 560817u /* link timer expired */
65
66 /*
67 * The following two 'message types' is really just implementation
68 * data conveniently stored in the message header.
69 * They must not be considered part of the protocol
70 */
71 #define OPEN_MSG 0
72 #define CLOSED_MSG 1
73
74 /*
75 * State value stored in 'exp_msg_count'
76 */
77 #define START_CHANGEOVER 100000u
78
79 static void link_handle_out_of_seq_msg(struct tipc_link *l_ptr,
80 struct sk_buff *buf);
81 static void tipc_link_proto_rcv(struct tipc_link *l_ptr, struct sk_buff *buf);
82 static int tipc_link_tunnel_rcv(struct tipc_node *n_ptr,
83 struct sk_buff **buf);
84 static void link_set_supervision_props(struct tipc_link *l_ptr, u32 tolerance);
85 static void link_state_event(struct tipc_link *l_ptr, u32 event);
86 static void link_reset_statistics(struct tipc_link *l_ptr);
87 static void link_print(struct tipc_link *l_ptr, const char *str);
88 static void tipc_link_sync_xmit(struct tipc_link *l);
89 static void tipc_link_sync_rcv(struct tipc_node *n, struct sk_buff *buf);
90 static int tipc_link_input(struct tipc_link *l, struct sk_buff *buf);
91 static int tipc_link_prepare_input(struct tipc_link *l, struct sk_buff **buf);
92
93 /*
94 * Simple link routines
95 */
96 static unsigned int align(unsigned int i)
97 {
98 return (i + 3) & ~3u;
99 }
100
101 static void link_init_max_pkt(struct tipc_link *l_ptr)
102 {
103 struct tipc_bearer *b_ptr;
104 u32 max_pkt;
105
106 rcu_read_lock();
107 b_ptr = rcu_dereference_rtnl(bearer_list[l_ptr->bearer_id]);
108 if (!b_ptr) {
109 rcu_read_unlock();
110 return;
111 }
112 max_pkt = (b_ptr->mtu & ~3);
113 rcu_read_unlock();
114
115 if (max_pkt > MAX_MSG_SIZE)
116 max_pkt = MAX_MSG_SIZE;
117
118 l_ptr->max_pkt_target = max_pkt;
119 if (l_ptr->max_pkt_target < MAX_PKT_DEFAULT)
120 l_ptr->max_pkt = l_ptr->max_pkt_target;
121 else
122 l_ptr->max_pkt = MAX_PKT_DEFAULT;
123
124 l_ptr->max_pkt_probes = 0;
125 }
126
127 static u32 link_next_sent(struct tipc_link *l_ptr)
128 {
129 if (l_ptr->next_out)
130 return buf_seqno(l_ptr->next_out);
131 return mod(l_ptr->next_out_no);
132 }
133
134 static u32 link_last_sent(struct tipc_link *l_ptr)
135 {
136 return mod(link_next_sent(l_ptr) - 1);
137 }
138
139 /*
140 * Simple non-static link routines (i.e. referenced outside this file)
141 */
142 int tipc_link_is_up(struct tipc_link *l_ptr)
143 {
144 if (!l_ptr)
145 return 0;
146 return link_working_working(l_ptr) || link_working_unknown(l_ptr);
147 }
148
149 int tipc_link_is_active(struct tipc_link *l_ptr)
150 {
151 return (l_ptr->owner->active_links[0] == l_ptr) ||
152 (l_ptr->owner->active_links[1] == l_ptr);
153 }
154
155 /**
156 * link_timeout - handle expiration of link timer
157 * @l_ptr: pointer to link
158 */
159 static void link_timeout(struct tipc_link *l_ptr)
160 {
161 tipc_node_lock(l_ptr->owner);
162
163 /* update counters used in statistical profiling of send traffic */
164 l_ptr->stats.accu_queue_sz += l_ptr->out_queue_size;
165 l_ptr->stats.queue_sz_counts++;
166
167 if (l_ptr->first_out) {
168 struct tipc_msg *msg = buf_msg(l_ptr->first_out);
169 u32 length = msg_size(msg);
170
171 if ((msg_user(msg) == MSG_FRAGMENTER) &&
172 (msg_type(msg) == FIRST_FRAGMENT)) {
173 length = msg_size(msg_get_wrapped(msg));
174 }
175 if (length) {
176 l_ptr->stats.msg_lengths_total += length;
177 l_ptr->stats.msg_length_counts++;
178 if (length <= 64)
179 l_ptr->stats.msg_length_profile[0]++;
180 else if (length <= 256)
181 l_ptr->stats.msg_length_profile[1]++;
182 else if (length <= 1024)
183 l_ptr->stats.msg_length_profile[2]++;
184 else if (length <= 4096)
185 l_ptr->stats.msg_length_profile[3]++;
186 else if (length <= 16384)
187 l_ptr->stats.msg_length_profile[4]++;
188 else if (length <= 32768)
189 l_ptr->stats.msg_length_profile[5]++;
190 else
191 l_ptr->stats.msg_length_profile[6]++;
192 }
193 }
194
195 /* do all other link processing performed on a periodic basis */
196
197 link_state_event(l_ptr, TIMEOUT_EVT);
198
199 if (l_ptr->next_out)
200 tipc_link_push_queue(l_ptr);
201
202 tipc_node_unlock(l_ptr->owner);
203 }
204
205 static void link_set_timer(struct tipc_link *l_ptr, u32 time)
206 {
207 k_start_timer(&l_ptr->timer, time);
208 }
209
210 /**
211 * tipc_link_create - create a new link
212 * @n_ptr: pointer to associated node
213 * @b_ptr: pointer to associated bearer
214 * @media_addr: media address to use when sending messages over link
215 *
216 * Returns pointer to link.
217 */
218 struct tipc_link *tipc_link_create(struct tipc_node *n_ptr,
219 struct tipc_bearer *b_ptr,
220 const struct tipc_media_addr *media_addr)
221 {
222 struct tipc_link *l_ptr;
223 struct tipc_msg *msg;
224 char *if_name;
225 char addr_string[16];
226 u32 peer = n_ptr->addr;
227
228 if (n_ptr->link_cnt >= 2) {
229 tipc_addr_string_fill(addr_string, n_ptr->addr);
230 pr_err("Attempt to establish third link to %s\n", addr_string);
231 return NULL;
232 }
233
234 if (n_ptr->links[b_ptr->identity]) {
235 tipc_addr_string_fill(addr_string, n_ptr->addr);
236 pr_err("Attempt to establish second link on <%s> to %s\n",
237 b_ptr->name, addr_string);
238 return NULL;
239 }
240
241 l_ptr = kzalloc(sizeof(*l_ptr), GFP_ATOMIC);
242 if (!l_ptr) {
243 pr_warn("Link creation failed, no memory\n");
244 return NULL;
245 }
246
247 l_ptr->addr = peer;
248 if_name = strchr(b_ptr->name, ':') + 1;
249 sprintf(l_ptr->name, "%u.%u.%u:%s-%u.%u.%u:unknown",
250 tipc_zone(tipc_own_addr), tipc_cluster(tipc_own_addr),
251 tipc_node(tipc_own_addr),
252 if_name,
253 tipc_zone(peer), tipc_cluster(peer), tipc_node(peer));
254 /* note: peer i/f name is updated by reset/activate message */
255 memcpy(&l_ptr->media_addr, media_addr, sizeof(*media_addr));
256 l_ptr->owner = n_ptr;
257 l_ptr->checkpoint = 1;
258 l_ptr->peer_session = INVALID_SESSION;
259 l_ptr->bearer_id = b_ptr->identity;
260 link_set_supervision_props(l_ptr, b_ptr->tolerance);
261 l_ptr->state = RESET_UNKNOWN;
262
263 l_ptr->pmsg = (struct tipc_msg *)&l_ptr->proto_msg;
264 msg = l_ptr->pmsg;
265 tipc_msg_init(msg, LINK_PROTOCOL, RESET_MSG, INT_H_SIZE, l_ptr->addr);
266 msg_set_size(msg, sizeof(l_ptr->proto_msg));
267 msg_set_session(msg, (tipc_random & 0xffff));
268 msg_set_bearer_id(msg, b_ptr->identity);
269 strcpy((char *)msg_data(msg), if_name);
270
271 l_ptr->priority = b_ptr->priority;
272 tipc_link_set_queue_limits(l_ptr, b_ptr->window);
273
274 l_ptr->net_plane = b_ptr->net_plane;
275 link_init_max_pkt(l_ptr);
276
277 l_ptr->next_out_no = 1;
278 INIT_LIST_HEAD(&l_ptr->waiting_ports);
279
280 link_reset_statistics(l_ptr);
281
282 tipc_node_attach_link(n_ptr, l_ptr);
283
284 k_init_timer(&l_ptr->timer, (Handler)link_timeout,
285 (unsigned long)l_ptr);
286
287 link_state_event(l_ptr, STARTING_EVT);
288
289 return l_ptr;
290 }
291
292 void tipc_link_delete_list(unsigned int bearer_id, bool shutting_down)
293 {
294 struct tipc_link *l_ptr;
295 struct tipc_node *n_ptr;
296
297 rcu_read_lock();
298 list_for_each_entry_rcu(n_ptr, &tipc_node_list, list) {
299 tipc_node_lock(n_ptr);
300 l_ptr = n_ptr->links[bearer_id];
301 if (l_ptr) {
302 tipc_link_reset(l_ptr);
303 if (shutting_down || !tipc_node_is_up(n_ptr)) {
304 tipc_node_detach_link(l_ptr->owner, l_ptr);
305 tipc_link_reset_fragments(l_ptr);
306 tipc_node_unlock(n_ptr);
307
308 /* Nobody else can access this link now: */
309 del_timer_sync(&l_ptr->timer);
310 kfree(l_ptr);
311 } else {
312 /* Detach/delete when failover is finished: */
313 l_ptr->flags |= LINK_STOPPED;
314 tipc_node_unlock(n_ptr);
315 del_timer_sync(&l_ptr->timer);
316 }
317 continue;
318 }
319 tipc_node_unlock(n_ptr);
320 }
321 rcu_read_unlock();
322 }
323
324 /**
325 * link_schedule_port - schedule port for deferred sending
326 * @l_ptr: pointer to link
327 * @origport: reference to sending port
328 * @sz: amount of data to be sent
329 *
330 * Schedules port for renewed sending of messages after link congestion
331 * has abated.
332 */
333 static int link_schedule_port(struct tipc_link *l_ptr, u32 origport, u32 sz)
334 {
335 struct tipc_port *p_ptr;
336 struct tipc_sock *tsk;
337
338 spin_lock_bh(&tipc_port_list_lock);
339 p_ptr = tipc_port_lock(origport);
340 if (p_ptr) {
341 if (!list_empty(&p_ptr->wait_list))
342 goto exit;
343 tsk = tipc_port_to_sock(p_ptr);
344 tsk->link_cong = 1;
345 p_ptr->waiting_pkts = 1 + ((sz - 1) / l_ptr->max_pkt);
346 list_add_tail(&p_ptr->wait_list, &l_ptr->waiting_ports);
347 l_ptr->stats.link_congs++;
348 exit:
349 tipc_port_unlock(p_ptr);
350 }
351 spin_unlock_bh(&tipc_port_list_lock);
352 return -ELINKCONG;
353 }
354
355 void tipc_link_wakeup_ports(struct tipc_link *l_ptr, int all)
356 {
357 struct tipc_port *p_ptr;
358 struct tipc_sock *tsk;
359 struct tipc_port *temp_p_ptr;
360 int win = l_ptr->queue_limit[0] - l_ptr->out_queue_size;
361
362 if (all)
363 win = 100000;
364 if (win <= 0)
365 return;
366 if (!spin_trylock_bh(&tipc_port_list_lock))
367 return;
368 if (link_congested(l_ptr))
369 goto exit;
370 list_for_each_entry_safe(p_ptr, temp_p_ptr, &l_ptr->waiting_ports,
371 wait_list) {
372 if (win <= 0)
373 break;
374 tsk = tipc_port_to_sock(p_ptr);
375 list_del_init(&p_ptr->wait_list);
376 spin_lock_bh(p_ptr->lock);
377 tsk->link_cong = 0;
378 tipc_sock_wakeup(tsk);
379 win -= p_ptr->waiting_pkts;
380 spin_unlock_bh(p_ptr->lock);
381 }
382
383 exit:
384 spin_unlock_bh(&tipc_port_list_lock);
385 }
386
387 /**
388 * link_release_outqueue - purge link's outbound message queue
389 * @l_ptr: pointer to link
390 */
391 static void link_release_outqueue(struct tipc_link *l_ptr)
392 {
393 kfree_skb_list(l_ptr->first_out);
394 l_ptr->first_out = NULL;
395 l_ptr->out_queue_size = 0;
396 }
397
398 /**
399 * tipc_link_reset_fragments - purge link's inbound message fragments queue
400 * @l_ptr: pointer to link
401 */
402 void tipc_link_reset_fragments(struct tipc_link *l_ptr)
403 {
404 kfree_skb(l_ptr->reasm_buf);
405 l_ptr->reasm_buf = NULL;
406 }
407
408 /**
409 * tipc_link_purge_queues - purge all pkt queues associated with link
410 * @l_ptr: pointer to link
411 */
412 void tipc_link_purge_queues(struct tipc_link *l_ptr)
413 {
414 kfree_skb_list(l_ptr->oldest_deferred_in);
415 kfree_skb_list(l_ptr->first_out);
416 tipc_link_reset_fragments(l_ptr);
417 kfree_skb(l_ptr->proto_msg_queue);
418 l_ptr->proto_msg_queue = NULL;
419 }
420
421 void tipc_link_reset(struct tipc_link *l_ptr)
422 {
423 u32 prev_state = l_ptr->state;
424 u32 checkpoint = l_ptr->next_in_no;
425 int was_active_link = tipc_link_is_active(l_ptr);
426
427 msg_set_session(l_ptr->pmsg, ((msg_session(l_ptr->pmsg) + 1) & 0xffff));
428
429 /* Link is down, accept any session */
430 l_ptr->peer_session = INVALID_SESSION;
431
432 /* Prepare for max packet size negotiation */
433 link_init_max_pkt(l_ptr);
434
435 l_ptr->state = RESET_UNKNOWN;
436
437 if ((prev_state == RESET_UNKNOWN) || (prev_state == RESET_RESET))
438 return;
439
440 tipc_node_link_down(l_ptr->owner, l_ptr);
441 tipc_bearer_remove_dest(l_ptr->bearer_id, l_ptr->addr);
442
443 if (was_active_link && tipc_node_active_links(l_ptr->owner)) {
444 l_ptr->reset_checkpoint = checkpoint;
445 l_ptr->exp_msg_count = START_CHANGEOVER;
446 }
447
448 /* Clean up all queues: */
449 link_release_outqueue(l_ptr);
450 kfree_skb(l_ptr->proto_msg_queue);
451 l_ptr->proto_msg_queue = NULL;
452 kfree_skb_list(l_ptr->oldest_deferred_in);
453 if (!list_empty(&l_ptr->waiting_ports))
454 tipc_link_wakeup_ports(l_ptr, 1);
455
456 l_ptr->retransm_queue_head = 0;
457 l_ptr->retransm_queue_size = 0;
458 l_ptr->last_out = NULL;
459 l_ptr->first_out = NULL;
460 l_ptr->next_out = NULL;
461 l_ptr->unacked_window = 0;
462 l_ptr->checkpoint = 1;
463 l_ptr->next_out_no = 1;
464 l_ptr->deferred_inqueue_sz = 0;
465 l_ptr->oldest_deferred_in = NULL;
466 l_ptr->newest_deferred_in = NULL;
467 l_ptr->fsm_msg_cnt = 0;
468 l_ptr->stale_count = 0;
469 link_reset_statistics(l_ptr);
470 }
471
472 void tipc_link_reset_list(unsigned int bearer_id)
473 {
474 struct tipc_link *l_ptr;
475 struct tipc_node *n_ptr;
476
477 rcu_read_lock();
478 list_for_each_entry_rcu(n_ptr, &tipc_node_list, list) {
479 tipc_node_lock(n_ptr);
480 l_ptr = n_ptr->links[bearer_id];
481 if (l_ptr)
482 tipc_link_reset(l_ptr);
483 tipc_node_unlock(n_ptr);
484 }
485 rcu_read_unlock();
486 }
487
488 static void link_activate(struct tipc_link *l_ptr)
489 {
490 l_ptr->next_in_no = l_ptr->stats.recv_info = 1;
491 tipc_node_link_up(l_ptr->owner, l_ptr);
492 tipc_bearer_add_dest(l_ptr->bearer_id, l_ptr->addr);
493 }
494
495 /**
496 * link_state_event - link finite state machine
497 * @l_ptr: pointer to link
498 * @event: state machine event to process
499 */
500 static void link_state_event(struct tipc_link *l_ptr, unsigned int event)
501 {
502 struct tipc_link *other;
503 u32 cont_intv = l_ptr->continuity_interval;
504
505 if (l_ptr->flags & LINK_STOPPED)
506 return;
507
508 if (!(l_ptr->flags & LINK_STARTED) && (event != STARTING_EVT))
509 return; /* Not yet. */
510
511 /* Check whether changeover is going on */
512 if (l_ptr->exp_msg_count) {
513 if (event == TIMEOUT_EVT)
514 link_set_timer(l_ptr, cont_intv);
515 return;
516 }
517
518 switch (l_ptr->state) {
519 case WORKING_WORKING:
520 switch (event) {
521 case TRAFFIC_MSG_EVT:
522 case ACTIVATE_MSG:
523 break;
524 case TIMEOUT_EVT:
525 if (l_ptr->next_in_no != l_ptr->checkpoint) {
526 l_ptr->checkpoint = l_ptr->next_in_no;
527 if (tipc_bclink_acks_missing(l_ptr->owner)) {
528 tipc_link_proto_xmit(l_ptr, STATE_MSG,
529 0, 0, 0, 0, 0);
530 l_ptr->fsm_msg_cnt++;
531 } else if (l_ptr->max_pkt < l_ptr->max_pkt_target) {
532 tipc_link_proto_xmit(l_ptr, STATE_MSG,
533 1, 0, 0, 0, 0);
534 l_ptr->fsm_msg_cnt++;
535 }
536 link_set_timer(l_ptr, cont_intv);
537 break;
538 }
539 l_ptr->state = WORKING_UNKNOWN;
540 l_ptr->fsm_msg_cnt = 0;
541 tipc_link_proto_xmit(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
542 l_ptr->fsm_msg_cnt++;
543 link_set_timer(l_ptr, cont_intv / 4);
544 break;
545 case RESET_MSG:
546 pr_info("%s<%s>, requested by peer\n", link_rst_msg,
547 l_ptr->name);
548 tipc_link_reset(l_ptr);
549 l_ptr->state = RESET_RESET;
550 l_ptr->fsm_msg_cnt = 0;
551 tipc_link_proto_xmit(l_ptr, ACTIVATE_MSG,
552 0, 0, 0, 0, 0);
553 l_ptr->fsm_msg_cnt++;
554 link_set_timer(l_ptr, cont_intv);
555 break;
556 default:
557 pr_err("%s%u in WW state\n", link_unk_evt, event);
558 }
559 break;
560 case WORKING_UNKNOWN:
561 switch (event) {
562 case TRAFFIC_MSG_EVT:
563 case ACTIVATE_MSG:
564 l_ptr->state = WORKING_WORKING;
565 l_ptr->fsm_msg_cnt = 0;
566 link_set_timer(l_ptr, cont_intv);
567 break;
568 case RESET_MSG:
569 pr_info("%s<%s>, requested by peer while probing\n",
570 link_rst_msg, l_ptr->name);
571 tipc_link_reset(l_ptr);
572 l_ptr->state = RESET_RESET;
573 l_ptr->fsm_msg_cnt = 0;
574 tipc_link_proto_xmit(l_ptr, ACTIVATE_MSG,
575 0, 0, 0, 0, 0);
576 l_ptr->fsm_msg_cnt++;
577 link_set_timer(l_ptr, cont_intv);
578 break;
579 case TIMEOUT_EVT:
580 if (l_ptr->next_in_no != l_ptr->checkpoint) {
581 l_ptr->state = WORKING_WORKING;
582 l_ptr->fsm_msg_cnt = 0;
583 l_ptr->checkpoint = l_ptr->next_in_no;
584 if (tipc_bclink_acks_missing(l_ptr->owner)) {
585 tipc_link_proto_xmit(l_ptr, STATE_MSG,
586 0, 0, 0, 0, 0);
587 l_ptr->fsm_msg_cnt++;
588 }
589 link_set_timer(l_ptr, cont_intv);
590 } else if (l_ptr->fsm_msg_cnt < l_ptr->abort_limit) {
591 tipc_link_proto_xmit(l_ptr, STATE_MSG,
592 1, 0, 0, 0, 0);
593 l_ptr->fsm_msg_cnt++;
594 link_set_timer(l_ptr, cont_intv / 4);
595 } else { /* Link has failed */
596 pr_warn("%s<%s>, peer not responding\n",
597 link_rst_msg, l_ptr->name);
598 tipc_link_reset(l_ptr);
599 l_ptr->state = RESET_UNKNOWN;
600 l_ptr->fsm_msg_cnt = 0;
601 tipc_link_proto_xmit(l_ptr, RESET_MSG,
602 0, 0, 0, 0, 0);
603 l_ptr->fsm_msg_cnt++;
604 link_set_timer(l_ptr, cont_intv);
605 }
606 break;
607 default:
608 pr_err("%s%u in WU state\n", link_unk_evt, event);
609 }
610 break;
611 case RESET_UNKNOWN:
612 switch (event) {
613 case TRAFFIC_MSG_EVT:
614 break;
615 case ACTIVATE_MSG:
616 other = l_ptr->owner->active_links[0];
617 if (other && link_working_unknown(other))
618 break;
619 l_ptr->state = WORKING_WORKING;
620 l_ptr->fsm_msg_cnt = 0;
621 link_activate(l_ptr);
622 tipc_link_proto_xmit(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
623 l_ptr->fsm_msg_cnt++;
624 if (l_ptr->owner->working_links == 1)
625 tipc_link_sync_xmit(l_ptr);
626 link_set_timer(l_ptr, cont_intv);
627 break;
628 case RESET_MSG:
629 l_ptr->state = RESET_RESET;
630 l_ptr->fsm_msg_cnt = 0;
631 tipc_link_proto_xmit(l_ptr, ACTIVATE_MSG,
632 1, 0, 0, 0, 0);
633 l_ptr->fsm_msg_cnt++;
634 link_set_timer(l_ptr, cont_intv);
635 break;
636 case STARTING_EVT:
637 l_ptr->flags |= LINK_STARTED;
638 /* fall through */
639 case TIMEOUT_EVT:
640 tipc_link_proto_xmit(l_ptr, RESET_MSG, 0, 0, 0, 0, 0);
641 l_ptr->fsm_msg_cnt++;
642 link_set_timer(l_ptr, cont_intv);
643 break;
644 default:
645 pr_err("%s%u in RU state\n", link_unk_evt, event);
646 }
647 break;
648 case RESET_RESET:
649 switch (event) {
650 case TRAFFIC_MSG_EVT:
651 case ACTIVATE_MSG:
652 other = l_ptr->owner->active_links[0];
653 if (other && link_working_unknown(other))
654 break;
655 l_ptr->state = WORKING_WORKING;
656 l_ptr->fsm_msg_cnt = 0;
657 link_activate(l_ptr);
658 tipc_link_proto_xmit(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
659 l_ptr->fsm_msg_cnt++;
660 if (l_ptr->owner->working_links == 1)
661 tipc_link_sync_xmit(l_ptr);
662 link_set_timer(l_ptr, cont_intv);
663 break;
664 case RESET_MSG:
665 break;
666 case TIMEOUT_EVT:
667 tipc_link_proto_xmit(l_ptr, ACTIVATE_MSG,
668 0, 0, 0, 0, 0);
669 l_ptr->fsm_msg_cnt++;
670 link_set_timer(l_ptr, cont_intv);
671 break;
672 default:
673 pr_err("%s%u in RR state\n", link_unk_evt, event);
674 }
675 break;
676 default:
677 pr_err("Unknown link state %u/%u\n", l_ptr->state, event);
678 }
679 }
680
681 /* tipc_link_cong: determine return value and how to treat the
682 * sent buffer during link congestion.
683 * - For plain, errorless user data messages we keep the buffer and
684 * return -ELINKONG.
685 * - For all other messages we discard the buffer and return -EHOSTUNREACH
686 * - For TIPC internal messages we also reset the link
687 */
688 static int tipc_link_cong(struct tipc_link *link, struct sk_buff *buf)
689 {
690 struct tipc_msg *msg = buf_msg(buf);
691 uint psz = msg_size(msg);
692 uint imp = tipc_msg_tot_importance(msg);
693 u32 oport = msg_tot_origport(msg);
694
695 if (likely(imp <= TIPC_CRITICAL_IMPORTANCE)) {
696 if (!msg_errcode(msg) && !msg_reroute_cnt(msg)) {
697 link_schedule_port(link, oport, psz);
698 return -ELINKCONG;
699 }
700 } else {
701 pr_warn("%s<%s>, send queue full", link_rst_msg, link->name);
702 tipc_link_reset(link);
703 }
704 kfree_skb_list(buf);
705 return -EHOSTUNREACH;
706 }
707
708 /**
709 * __tipc_link_xmit(): same as tipc_link_xmit, but destlink is known & locked
710 * @link: link to use
711 * @buf: chain of buffers containing message
712 * Consumes the buffer chain, except when returning -ELINKCONG
713 * Returns 0 if success, otherwise errno: -ELINKCONG, -EMSGSIZE (plain socket
714 * user data messages) or -EHOSTUNREACH (all other messages/senders)
715 * Only the socket functions tipc_send_stream() and tipc_send_packet() need
716 * to act on the return value, since they may need to do more send attempts.
717 */
718 int __tipc_link_xmit(struct tipc_link *link, struct sk_buff *buf)
719 {
720 struct tipc_msg *msg = buf_msg(buf);
721 uint psz = msg_size(msg);
722 uint qsz = link->out_queue_size;
723 uint sndlim = link->queue_limit[0];
724 uint imp = tipc_msg_tot_importance(msg);
725 uint mtu = link->max_pkt;
726 uint ack = mod(link->next_in_no - 1);
727 uint seqno = link->next_out_no;
728 uint bc_last_in = link->owner->bclink.last_in;
729 struct tipc_media_addr *addr = &link->media_addr;
730 struct sk_buff *next = buf->next;
731
732 /* Match queue limits against msg importance: */
733 if (unlikely(qsz >= link->queue_limit[imp]))
734 return tipc_link_cong(link, buf);
735
736 /* Has valid packet limit been used ? */
737 if (unlikely(psz > mtu)) {
738 kfree_skb_list(buf);
739 return -EMSGSIZE;
740 }
741
742 /* Prepare each packet for sending, and add to outqueue: */
743 while (buf) {
744 next = buf->next;
745 msg = buf_msg(buf);
746 msg_set_word(msg, 2, ((ack << 16) | mod(seqno)));
747 msg_set_bcast_ack(msg, bc_last_in);
748
749 if (!link->first_out) {
750 link->first_out = buf;
751 } else if (qsz < sndlim) {
752 link->last_out->next = buf;
753 } else if (tipc_msg_bundle(link->last_out, buf, mtu)) {
754 link->stats.sent_bundled++;
755 buf = next;
756 next = buf->next;
757 continue;
758 } else if (tipc_msg_make_bundle(&buf, mtu, link->addr)) {
759 link->stats.sent_bundled++;
760 link->stats.sent_bundles++;
761 link->last_out->next = buf;
762 if (!link->next_out)
763 link->next_out = buf;
764 } else {
765 link->last_out->next = buf;
766 if (!link->next_out)
767 link->next_out = buf;
768 }
769
770 /* Send packet if possible: */
771 if (likely(++qsz <= sndlim)) {
772 tipc_bearer_send(link->bearer_id, buf, addr);
773 link->next_out = next;
774 link->unacked_window = 0;
775 }
776 seqno++;
777 link->last_out = buf;
778 buf = next;
779 }
780 link->next_out_no = seqno;
781 link->out_queue_size = qsz;
782 return 0;
783 }
784
785 /**
786 * tipc_link_xmit() is the general link level function for message sending
787 * @buf: chain of buffers containing message
788 * @dsz: amount of user data to be sent
789 * @dnode: address of destination node
790 * @selector: a number used for deterministic link selection
791 * Consumes the buffer chain, except when returning -ELINKCONG
792 * Returns 0 if success, otherwise errno: -ELINKCONG,-EHOSTUNREACH,-EMSGSIZE
793 */
794 int tipc_link_xmit(struct sk_buff *buf, u32 dnode, u32 selector)
795 {
796 struct tipc_link *link = NULL;
797 struct tipc_node *node;
798 int rc = -EHOSTUNREACH;
799
800 node = tipc_node_find(dnode);
801 if (node) {
802 tipc_node_lock(node);
803 link = node->active_links[selector & 1];
804 if (link)
805 rc = __tipc_link_xmit(link, buf);
806 tipc_node_unlock(node);
807 }
808
809 if (link)
810 return rc;
811
812 if (likely(in_own_node(dnode)))
813 return tipc_sk_rcv(buf);
814
815 kfree_skb_list(buf);
816 return rc;
817 }
818
819 /*
820 * tipc_link_sync_xmit - synchronize broadcast link endpoints.
821 *
822 * Give a newly added peer node the sequence number where it should
823 * start receiving and acking broadcast packets.
824 *
825 * Called with node locked
826 */
827 static void tipc_link_sync_xmit(struct tipc_link *link)
828 {
829 struct sk_buff *buf;
830 struct tipc_msg *msg;
831
832 buf = tipc_buf_acquire(INT_H_SIZE);
833 if (!buf)
834 return;
835
836 msg = buf_msg(buf);
837 tipc_msg_init(msg, BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE, link->addr);
838 msg_set_last_bcast(msg, link->owner->bclink.acked);
839 __tipc_link_xmit(link, buf);
840 }
841
842 /*
843 * tipc_link_sync_rcv - synchronize broadcast link endpoints.
844 * Receive the sequence number where we should start receiving and
845 * acking broadcast packets from a newly added peer node, and open
846 * up for reception of such packets.
847 *
848 * Called with node locked
849 */
850 static void tipc_link_sync_rcv(struct tipc_node *n, struct sk_buff *buf)
851 {
852 struct tipc_msg *msg = buf_msg(buf);
853
854 n->bclink.last_sent = n->bclink.last_in = msg_last_bcast(msg);
855 n->bclink.recv_permitted = true;
856 kfree_skb(buf);
857 }
858
859 /*
860 * tipc_link_push_packet: Push one unsent packet to the media
861 */
862 static u32 tipc_link_push_packet(struct tipc_link *l_ptr)
863 {
864 struct sk_buff *buf = l_ptr->first_out;
865 u32 r_q_size = l_ptr->retransm_queue_size;
866 u32 r_q_head = l_ptr->retransm_queue_head;
867
868 /* Step to position where retransmission failed, if any, */
869 /* consider that buffers may have been released in meantime */
870 if (r_q_size && buf) {
871 u32 last = lesser(mod(r_q_head + r_q_size),
872 link_last_sent(l_ptr));
873 u32 first = buf_seqno(buf);
874
875 while (buf && less(first, r_q_head)) {
876 first = mod(first + 1);
877 buf = buf->next;
878 }
879 l_ptr->retransm_queue_head = r_q_head = first;
880 l_ptr->retransm_queue_size = r_q_size = mod(last - first);
881 }
882
883 /* Continue retransmission now, if there is anything: */
884 if (r_q_size && buf) {
885 msg_set_ack(buf_msg(buf), mod(l_ptr->next_in_no - 1));
886 msg_set_bcast_ack(buf_msg(buf), l_ptr->owner->bclink.last_in);
887 tipc_bearer_send(l_ptr->bearer_id, buf, &l_ptr->media_addr);
888 l_ptr->retransm_queue_head = mod(++r_q_head);
889 l_ptr->retransm_queue_size = --r_q_size;
890 l_ptr->stats.retransmitted++;
891 return 0;
892 }
893
894 /* Send deferred protocol message, if any: */
895 buf = l_ptr->proto_msg_queue;
896 if (buf) {
897 msg_set_ack(buf_msg(buf), mod(l_ptr->next_in_no - 1));
898 msg_set_bcast_ack(buf_msg(buf), l_ptr->owner->bclink.last_in);
899 tipc_bearer_send(l_ptr->bearer_id, buf, &l_ptr->media_addr);
900 l_ptr->unacked_window = 0;
901 kfree_skb(buf);
902 l_ptr->proto_msg_queue = NULL;
903 return 0;
904 }
905
906 /* Send one deferred data message, if send window not full: */
907 buf = l_ptr->next_out;
908 if (buf) {
909 struct tipc_msg *msg = buf_msg(buf);
910 u32 next = msg_seqno(msg);
911 u32 first = buf_seqno(l_ptr->first_out);
912
913 if (mod(next - first) < l_ptr->queue_limit[0]) {
914 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
915 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
916 tipc_bearer_send(l_ptr->bearer_id, buf,
917 &l_ptr->media_addr);
918 if (msg_user(msg) == MSG_BUNDLER)
919 msg_set_type(msg, BUNDLE_CLOSED);
920 l_ptr->next_out = buf->next;
921 return 0;
922 }
923 }
924 return 1;
925 }
926
927 /*
928 * push_queue(): push out the unsent messages of a link where
929 * congestion has abated. Node is locked
930 */
931 void tipc_link_push_queue(struct tipc_link *l_ptr)
932 {
933 u32 res;
934
935 do {
936 res = tipc_link_push_packet(l_ptr);
937 } while (!res);
938 }
939
940 void tipc_link_reset_all(struct tipc_node *node)
941 {
942 char addr_string[16];
943 u32 i;
944
945 tipc_node_lock(node);
946
947 pr_warn("Resetting all links to %s\n",
948 tipc_addr_string_fill(addr_string, node->addr));
949
950 for (i = 0; i < MAX_BEARERS; i++) {
951 if (node->links[i]) {
952 link_print(node->links[i], "Resetting link\n");
953 tipc_link_reset(node->links[i]);
954 }
955 }
956
957 tipc_node_unlock(node);
958 }
959
960 static void link_retransmit_failure(struct tipc_link *l_ptr,
961 struct sk_buff *buf)
962 {
963 struct tipc_msg *msg = buf_msg(buf);
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();
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(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 *buf,
1002 u32 retransmits)
1003 {
1004 struct tipc_msg *msg;
1005
1006 if (!buf)
1007 return;
1008
1009 msg = buf_msg(buf);
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, buf);
1015 return;
1016 }
1017 } else {
1018 l_ptr->last_retransmitted = msg_seqno(msg);
1019 l_ptr->stale_count = 1;
1020 }
1021
1022 while (retransmits && (buf != l_ptr->next_out) && buf) {
1023 msg = buf_msg(buf);
1024 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
1025 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1026 tipc_bearer_send(l_ptr->bearer_id, buf, &l_ptr->media_addr);
1027 buf = buf->next;
1028 retransmits--;
1029 l_ptr->stats.retransmitted++;
1030 }
1031
1032 l_ptr->retransm_queue_head = l_ptr->retransm_queue_size = 0;
1033 }
1034
1035 /**
1036 * link_insert_deferred_queue - insert deferred messages back into receive chain
1037 */
1038 static struct sk_buff *link_insert_deferred_queue(struct tipc_link *l_ptr,
1039 struct sk_buff *buf)
1040 {
1041 u32 seq_no;
1042
1043 if (l_ptr->oldest_deferred_in == NULL)
1044 return buf;
1045
1046 seq_no = buf_seqno(l_ptr->oldest_deferred_in);
1047 if (seq_no == mod(l_ptr->next_in_no)) {
1048 l_ptr->newest_deferred_in->next = buf;
1049 buf = l_ptr->oldest_deferred_in;
1050 l_ptr->oldest_deferred_in = NULL;
1051 l_ptr->deferred_inqueue_sz = 0;
1052 }
1053 return buf;
1054 }
1055
1056 /**
1057 * link_recv_buf_validate - validate basic format of received message
1058 *
1059 * This routine ensures a TIPC message has an acceptable header, and at least
1060 * as much data as the header indicates it should. The routine also ensures
1061 * that the entire message header is stored in the main fragment of the message
1062 * buffer, to simplify future access to message header fields.
1063 *
1064 * Note: Having extra info present in the message header or data areas is OK.
1065 * TIPC will ignore the excess, under the assumption that it is optional info
1066 * introduced by a later release of the protocol.
1067 */
1068 static int link_recv_buf_validate(struct sk_buff *buf)
1069 {
1070 static u32 min_data_hdr_size[8] = {
1071 SHORT_H_SIZE, MCAST_H_SIZE, NAMED_H_SIZE, BASIC_H_SIZE,
1072 MAX_H_SIZE, MAX_H_SIZE, MAX_H_SIZE, MAX_H_SIZE
1073 };
1074
1075 struct tipc_msg *msg;
1076 u32 tipc_hdr[2];
1077 u32 size;
1078 u32 hdr_size;
1079 u32 min_hdr_size;
1080
1081 /* If this packet comes from the defer queue, the skb has already
1082 * been validated
1083 */
1084 if (unlikely(TIPC_SKB_CB(buf)->deferred))
1085 return 1;
1086
1087 if (unlikely(buf->len < MIN_H_SIZE))
1088 return 0;
1089
1090 msg = skb_header_pointer(buf, 0, sizeof(tipc_hdr), tipc_hdr);
1091 if (msg == NULL)
1092 return 0;
1093
1094 if (unlikely(msg_version(msg) != TIPC_VERSION))
1095 return 0;
1096
1097 size = msg_size(msg);
1098 hdr_size = msg_hdr_sz(msg);
1099 min_hdr_size = msg_isdata(msg) ?
1100 min_data_hdr_size[msg_type(msg)] : INT_H_SIZE;
1101
1102 if (unlikely((hdr_size < min_hdr_size) ||
1103 (size < hdr_size) ||
1104 (buf->len < size) ||
1105 (size - hdr_size > TIPC_MAX_USER_MSG_SIZE)))
1106 return 0;
1107
1108 return pskb_may_pull(buf, hdr_size);
1109 }
1110
1111 /**
1112 * tipc_rcv - process TIPC packets/messages arriving from off-node
1113 * @head: pointer to message buffer chain
1114 * @b_ptr: pointer to bearer message arrived on
1115 *
1116 * Invoked with no locks held. Bearer pointer must point to a valid bearer
1117 * structure (i.e. cannot be NULL), but bearer can be inactive.
1118 */
1119 void tipc_rcv(struct sk_buff *head, struct tipc_bearer *b_ptr)
1120 {
1121 while (head) {
1122 struct tipc_node *n_ptr;
1123 struct tipc_link *l_ptr;
1124 struct sk_buff *crs;
1125 struct sk_buff *buf = head;
1126 struct tipc_msg *msg;
1127 u32 seq_no;
1128 u32 ackd;
1129 u32 released = 0;
1130
1131 head = head->next;
1132 buf->next = NULL;
1133
1134 /* Ensure message is well-formed */
1135 if (unlikely(!link_recv_buf_validate(buf)))
1136 goto discard;
1137
1138 /* Ensure message data is a single contiguous unit */
1139 if (unlikely(skb_linearize(buf)))
1140 goto discard;
1141
1142 /* Handle arrival of a non-unicast link message */
1143 msg = buf_msg(buf);
1144
1145 if (unlikely(msg_non_seq(msg))) {
1146 if (msg_user(msg) == LINK_CONFIG)
1147 tipc_disc_rcv(buf, b_ptr);
1148 else
1149 tipc_bclink_rcv(buf);
1150 continue;
1151 }
1152
1153 /* Discard unicast link messages destined for another node */
1154 if (unlikely(!msg_short(msg) &&
1155 (msg_destnode(msg) != tipc_own_addr)))
1156 goto discard;
1157
1158 /* Locate neighboring node that sent message */
1159 n_ptr = tipc_node_find(msg_prevnode(msg));
1160 if (unlikely(!n_ptr))
1161 goto discard;
1162 tipc_node_lock(n_ptr);
1163
1164 /* Locate unicast link endpoint that should handle message */
1165 l_ptr = n_ptr->links[b_ptr->identity];
1166 if (unlikely(!l_ptr))
1167 goto unlock_discard;
1168
1169 /* Verify that communication with node is currently allowed */
1170 if ((n_ptr->action_flags & TIPC_WAIT_PEER_LINKS_DOWN) &&
1171 msg_user(msg) == LINK_PROTOCOL &&
1172 (msg_type(msg) == RESET_MSG ||
1173 msg_type(msg) == ACTIVATE_MSG) &&
1174 !msg_redundant_link(msg))
1175 n_ptr->action_flags &= ~TIPC_WAIT_PEER_LINKS_DOWN;
1176
1177 if (tipc_node_blocked(n_ptr))
1178 goto unlock_discard;
1179
1180 /* Validate message sequence number info */
1181 seq_no = msg_seqno(msg);
1182 ackd = msg_ack(msg);
1183
1184 /* Release acked messages */
1185 if (n_ptr->bclink.recv_permitted)
1186 tipc_bclink_acknowledge(n_ptr, msg_bcast_ack(msg));
1187
1188 crs = l_ptr->first_out;
1189 while ((crs != l_ptr->next_out) &&
1190 less_eq(buf_seqno(crs), ackd)) {
1191 struct sk_buff *next = crs->next;
1192 kfree_skb(crs);
1193 crs = next;
1194 released++;
1195 }
1196 if (released) {
1197 l_ptr->first_out = crs;
1198 l_ptr->out_queue_size -= released;
1199 }
1200
1201 /* Try sending any messages link endpoint has pending */
1202 if (unlikely(l_ptr->next_out))
1203 tipc_link_push_queue(l_ptr);
1204
1205 if (unlikely(!list_empty(&l_ptr->waiting_ports)))
1206 tipc_link_wakeup_ports(l_ptr, 0);
1207
1208 /* Process the incoming packet */
1209 if (unlikely(!link_working_working(l_ptr))) {
1210 if (msg_user(msg) == LINK_PROTOCOL) {
1211 tipc_link_proto_rcv(l_ptr, buf);
1212 head = link_insert_deferred_queue(l_ptr, head);
1213 tipc_node_unlock(n_ptr);
1214 continue;
1215 }
1216
1217 /* Traffic message. Conditionally activate link */
1218 link_state_event(l_ptr, TRAFFIC_MSG_EVT);
1219
1220 if (link_working_working(l_ptr)) {
1221 /* Re-insert buffer in front of queue */
1222 buf->next = head;
1223 head = buf;
1224 tipc_node_unlock(n_ptr);
1225 continue;
1226 }
1227 goto unlock_discard;
1228 }
1229
1230 /* Link is now in state WORKING_WORKING */
1231 if (unlikely(seq_no != mod(l_ptr->next_in_no))) {
1232 link_handle_out_of_seq_msg(l_ptr, buf);
1233 head = link_insert_deferred_queue(l_ptr, head);
1234 tipc_node_unlock(n_ptr);
1235 continue;
1236 }
1237 l_ptr->next_in_no++;
1238 if (unlikely(l_ptr->oldest_deferred_in))
1239 head = link_insert_deferred_queue(l_ptr, head);
1240
1241 if (unlikely(++l_ptr->unacked_window >= TIPC_MIN_LINK_WIN)) {
1242 l_ptr->stats.sent_acks++;
1243 tipc_link_proto_xmit(l_ptr, STATE_MSG, 0, 0, 0, 0, 0);
1244 }
1245
1246 if (tipc_link_prepare_input(l_ptr, &buf)) {
1247 tipc_node_unlock(n_ptr);
1248 continue;
1249 }
1250 tipc_node_unlock(n_ptr);
1251 msg = buf_msg(buf);
1252 if (tipc_link_input(l_ptr, buf) != 0)
1253 goto discard;
1254 continue;
1255 unlock_discard:
1256 tipc_node_unlock(n_ptr);
1257 discard:
1258 kfree_skb(buf);
1259 }
1260 }
1261
1262 /**
1263 * tipc_link_prepare_input - process TIPC link messages
1264 *
1265 * returns nonzero if the message was consumed
1266 *
1267 * Node lock must be held
1268 */
1269 static int tipc_link_prepare_input(struct tipc_link *l, struct sk_buff **buf)
1270 {
1271 struct tipc_node *n;
1272 struct tipc_msg *msg;
1273 int res = -EINVAL;
1274
1275 n = l->owner;
1276 msg = buf_msg(*buf);
1277 switch (msg_user(msg)) {
1278 case CHANGEOVER_PROTOCOL:
1279 if (tipc_link_tunnel_rcv(n, buf))
1280 res = 0;
1281 break;
1282 case MSG_FRAGMENTER:
1283 l->stats.recv_fragments++;
1284 if (tipc_buf_append(&l->reasm_buf, buf)) {
1285 l->stats.recv_fragmented++;
1286 res = 0;
1287 } else if (!l->reasm_buf) {
1288 tipc_link_reset(l);
1289 }
1290 break;
1291 case MSG_BUNDLER:
1292 l->stats.recv_bundles++;
1293 l->stats.recv_bundled += msg_msgcnt(msg);
1294 res = 0;
1295 break;
1296 case NAME_DISTRIBUTOR:
1297 n->bclink.recv_permitted = true;
1298 res = 0;
1299 break;
1300 case BCAST_PROTOCOL:
1301 tipc_link_sync_rcv(n, *buf);
1302 break;
1303 default:
1304 res = 0;
1305 }
1306 return res;
1307 }
1308 /**
1309 * tipc_link_input - Deliver message too higher layers
1310 */
1311 static int tipc_link_input(struct tipc_link *l, struct sk_buff *buf)
1312 {
1313 struct tipc_msg *msg = buf_msg(buf);
1314 int res = 0;
1315
1316 switch (msg_user(msg)) {
1317 case TIPC_LOW_IMPORTANCE:
1318 case TIPC_MEDIUM_IMPORTANCE:
1319 case TIPC_HIGH_IMPORTANCE:
1320 case TIPC_CRITICAL_IMPORTANCE:
1321 case CONN_MANAGER:
1322 tipc_sk_rcv(buf);
1323 break;
1324 case NAME_DISTRIBUTOR:
1325 tipc_named_rcv(buf);
1326 break;
1327 case MSG_BUNDLER:
1328 tipc_link_bundle_rcv(buf);
1329 break;
1330 default:
1331 res = -EINVAL;
1332 }
1333 return res;
1334 }
1335
1336 /**
1337 * tipc_link_defer_pkt - Add out-of-sequence message to deferred reception queue
1338 *
1339 * Returns increase in queue length (i.e. 0 or 1)
1340 */
1341 u32 tipc_link_defer_pkt(struct sk_buff **head, struct sk_buff **tail,
1342 struct sk_buff *buf)
1343 {
1344 struct sk_buff *queue_buf;
1345 struct sk_buff **prev;
1346 u32 seq_no = buf_seqno(buf);
1347
1348 buf->next = NULL;
1349
1350 /* Empty queue ? */
1351 if (*head == NULL) {
1352 *head = *tail = buf;
1353 return 1;
1354 }
1355
1356 /* Last ? */
1357 if (less(buf_seqno(*tail), seq_no)) {
1358 (*tail)->next = buf;
1359 *tail = buf;
1360 return 1;
1361 }
1362
1363 /* Locate insertion point in queue, then insert; discard if duplicate */
1364 prev = head;
1365 queue_buf = *head;
1366 for (;;) {
1367 u32 curr_seqno = buf_seqno(queue_buf);
1368
1369 if (seq_no == curr_seqno) {
1370 kfree_skb(buf);
1371 return 0;
1372 }
1373
1374 if (less(seq_no, curr_seqno))
1375 break;
1376
1377 prev = &queue_buf->next;
1378 queue_buf = queue_buf->next;
1379 }
1380
1381 buf->next = queue_buf;
1382 *prev = buf;
1383 return 1;
1384 }
1385
1386 /*
1387 * link_handle_out_of_seq_msg - handle arrival of out-of-sequence packet
1388 */
1389 static void link_handle_out_of_seq_msg(struct tipc_link *l_ptr,
1390 struct sk_buff *buf)
1391 {
1392 u32 seq_no = buf_seqno(buf);
1393
1394 if (likely(msg_user(buf_msg(buf)) == LINK_PROTOCOL)) {
1395 tipc_link_proto_rcv(l_ptr, buf);
1396 return;
1397 }
1398
1399 /* Record OOS packet arrival (force mismatch on next timeout) */
1400 l_ptr->checkpoint--;
1401
1402 /*
1403 * Discard packet if a duplicate; otherwise add it to deferred queue
1404 * and notify peer of gap as per protocol specification
1405 */
1406 if (less(seq_no, mod(l_ptr->next_in_no))) {
1407 l_ptr->stats.duplicates++;
1408 kfree_skb(buf);
1409 return;
1410 }
1411
1412 if (tipc_link_defer_pkt(&l_ptr->oldest_deferred_in,
1413 &l_ptr->newest_deferred_in, buf)) {
1414 l_ptr->deferred_inqueue_sz++;
1415 l_ptr->stats.deferred_recv++;
1416 TIPC_SKB_CB(buf)->deferred = true;
1417 if ((l_ptr->deferred_inqueue_sz % 16) == 1)
1418 tipc_link_proto_xmit(l_ptr, STATE_MSG, 0, 0, 0, 0, 0);
1419 } else
1420 l_ptr->stats.duplicates++;
1421 }
1422
1423 /*
1424 * Send protocol message to the other endpoint.
1425 */
1426 void tipc_link_proto_xmit(struct tipc_link *l_ptr, u32 msg_typ, int probe_msg,
1427 u32 gap, u32 tolerance, u32 priority, u32 ack_mtu)
1428 {
1429 struct sk_buff *buf = NULL;
1430 struct tipc_msg *msg = l_ptr->pmsg;
1431 u32 msg_size = sizeof(l_ptr->proto_msg);
1432 int r_flag;
1433
1434 /* Discard any previous message that was deferred due to congestion */
1435 if (l_ptr->proto_msg_queue) {
1436 kfree_skb(l_ptr->proto_msg_queue);
1437 l_ptr->proto_msg_queue = NULL;
1438 }
1439
1440 /* Don't send protocol message during link changeover */
1441 if (l_ptr->exp_msg_count)
1442 return;
1443
1444 /* Abort non-RESET send if communication with node is prohibited */
1445 if ((tipc_node_blocked(l_ptr->owner)) && (msg_typ != RESET_MSG))
1446 return;
1447
1448 /* Create protocol message with "out-of-sequence" sequence number */
1449 msg_set_type(msg, msg_typ);
1450 msg_set_net_plane(msg, l_ptr->net_plane);
1451 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1452 msg_set_last_bcast(msg, tipc_bclink_get_last_sent());
1453
1454 if (msg_typ == STATE_MSG) {
1455 u32 next_sent = mod(l_ptr->next_out_no);
1456
1457 if (!tipc_link_is_up(l_ptr))
1458 return;
1459 if (l_ptr->next_out)
1460 next_sent = buf_seqno(l_ptr->next_out);
1461 msg_set_next_sent(msg, next_sent);
1462 if (l_ptr->oldest_deferred_in) {
1463 u32 rec = buf_seqno(l_ptr->oldest_deferred_in);
1464 gap = mod(rec - mod(l_ptr->next_in_no));
1465 }
1466 msg_set_seq_gap(msg, gap);
1467 if (gap)
1468 l_ptr->stats.sent_nacks++;
1469 msg_set_link_tolerance(msg, tolerance);
1470 msg_set_linkprio(msg, priority);
1471 msg_set_max_pkt(msg, ack_mtu);
1472 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
1473 msg_set_probe(msg, probe_msg != 0);
1474 if (probe_msg) {
1475 u32 mtu = l_ptr->max_pkt;
1476
1477 if ((mtu < l_ptr->max_pkt_target) &&
1478 link_working_working(l_ptr) &&
1479 l_ptr->fsm_msg_cnt) {
1480 msg_size = (mtu + (l_ptr->max_pkt_target - mtu)/2 + 2) & ~3;
1481 if (l_ptr->max_pkt_probes == 10) {
1482 l_ptr->max_pkt_target = (msg_size - 4);
1483 l_ptr->max_pkt_probes = 0;
1484 msg_size = (mtu + (l_ptr->max_pkt_target - mtu)/2 + 2) & ~3;
1485 }
1486 l_ptr->max_pkt_probes++;
1487 }
1488
1489 l_ptr->stats.sent_probes++;
1490 }
1491 l_ptr->stats.sent_states++;
1492 } else { /* RESET_MSG or ACTIVATE_MSG */
1493 msg_set_ack(msg, mod(l_ptr->reset_checkpoint - 1));
1494 msg_set_seq_gap(msg, 0);
1495 msg_set_next_sent(msg, 1);
1496 msg_set_probe(msg, 0);
1497 msg_set_link_tolerance(msg, l_ptr->tolerance);
1498 msg_set_linkprio(msg, l_ptr->priority);
1499 msg_set_max_pkt(msg, l_ptr->max_pkt_target);
1500 }
1501
1502 r_flag = (l_ptr->owner->working_links > tipc_link_is_up(l_ptr));
1503 msg_set_redundant_link(msg, r_flag);
1504 msg_set_linkprio(msg, l_ptr->priority);
1505 msg_set_size(msg, msg_size);
1506
1507 msg_set_seqno(msg, mod(l_ptr->next_out_no + (0xffff/2)));
1508
1509 buf = tipc_buf_acquire(msg_size);
1510 if (!buf)
1511 return;
1512
1513 skb_copy_to_linear_data(buf, msg, sizeof(l_ptr->proto_msg));
1514 buf->priority = TC_PRIO_CONTROL;
1515
1516 tipc_bearer_send(l_ptr->bearer_id, buf, &l_ptr->media_addr);
1517 l_ptr->unacked_window = 0;
1518 kfree_skb(buf);
1519 }
1520
1521 /*
1522 * Receive protocol message :
1523 * Note that network plane id propagates through the network, and may
1524 * change at any time. The node with lowest address rules
1525 */
1526 static void tipc_link_proto_rcv(struct tipc_link *l_ptr, struct sk_buff *buf)
1527 {
1528 u32 rec_gap = 0;
1529 u32 max_pkt_info;
1530 u32 max_pkt_ack;
1531 u32 msg_tol;
1532 struct tipc_msg *msg = buf_msg(buf);
1533
1534 /* Discard protocol message during link changeover */
1535 if (l_ptr->exp_msg_count)
1536 goto exit;
1537
1538 if (l_ptr->net_plane != msg_net_plane(msg))
1539 if (tipc_own_addr > msg_prevnode(msg))
1540 l_ptr->net_plane = msg_net_plane(msg);
1541
1542 switch (msg_type(msg)) {
1543
1544 case RESET_MSG:
1545 if (!link_working_unknown(l_ptr) &&
1546 (l_ptr->peer_session != INVALID_SESSION)) {
1547 if (less_eq(msg_session(msg), l_ptr->peer_session))
1548 break; /* duplicate or old reset: ignore */
1549 }
1550
1551 if (!msg_redundant_link(msg) && (link_working_working(l_ptr) ||
1552 link_working_unknown(l_ptr))) {
1553 /*
1554 * peer has lost contact -- don't allow peer's links
1555 * to reactivate before we recognize loss & clean up
1556 */
1557 l_ptr->owner->action_flags |= TIPC_WAIT_OWN_LINKS_DOWN;
1558 }
1559
1560 link_state_event(l_ptr, RESET_MSG);
1561
1562 /* fall thru' */
1563 case ACTIVATE_MSG:
1564 /* Update link settings according other endpoint's values */
1565 strcpy((strrchr(l_ptr->name, ':') + 1), (char *)msg_data(msg));
1566
1567 msg_tol = msg_link_tolerance(msg);
1568 if (msg_tol > l_ptr->tolerance)
1569 link_set_supervision_props(l_ptr, msg_tol);
1570
1571 if (msg_linkprio(msg) > l_ptr->priority)
1572 l_ptr->priority = msg_linkprio(msg);
1573
1574 max_pkt_info = msg_max_pkt(msg);
1575 if (max_pkt_info) {
1576 if (max_pkt_info < l_ptr->max_pkt_target)
1577 l_ptr->max_pkt_target = max_pkt_info;
1578 if (l_ptr->max_pkt > l_ptr->max_pkt_target)
1579 l_ptr->max_pkt = l_ptr->max_pkt_target;
1580 } else {
1581 l_ptr->max_pkt = l_ptr->max_pkt_target;
1582 }
1583
1584 /* Synchronize broadcast link info, if not done previously */
1585 if (!tipc_node_is_up(l_ptr->owner)) {
1586 l_ptr->owner->bclink.last_sent =
1587 l_ptr->owner->bclink.last_in =
1588 msg_last_bcast(msg);
1589 l_ptr->owner->bclink.oos_state = 0;
1590 }
1591
1592 l_ptr->peer_session = msg_session(msg);
1593 l_ptr->peer_bearer_id = msg_bearer_id(msg);
1594
1595 if (msg_type(msg) == ACTIVATE_MSG)
1596 link_state_event(l_ptr, ACTIVATE_MSG);
1597 break;
1598 case STATE_MSG:
1599
1600 msg_tol = msg_link_tolerance(msg);
1601 if (msg_tol)
1602 link_set_supervision_props(l_ptr, msg_tol);
1603
1604 if (msg_linkprio(msg) &&
1605 (msg_linkprio(msg) != l_ptr->priority)) {
1606 pr_warn("%s<%s>, priority change %u->%u\n",
1607 link_rst_msg, l_ptr->name, l_ptr->priority,
1608 msg_linkprio(msg));
1609 l_ptr->priority = msg_linkprio(msg);
1610 tipc_link_reset(l_ptr); /* Enforce change to take effect */
1611 break;
1612 }
1613
1614 /* Record reception; force mismatch at next timeout: */
1615 l_ptr->checkpoint--;
1616
1617 link_state_event(l_ptr, TRAFFIC_MSG_EVT);
1618 l_ptr->stats.recv_states++;
1619 if (link_reset_unknown(l_ptr))
1620 break;
1621
1622 if (less_eq(mod(l_ptr->next_in_no), msg_next_sent(msg))) {
1623 rec_gap = mod(msg_next_sent(msg) -
1624 mod(l_ptr->next_in_no));
1625 }
1626
1627 max_pkt_ack = msg_max_pkt(msg);
1628 if (max_pkt_ack > l_ptr->max_pkt) {
1629 l_ptr->max_pkt = max_pkt_ack;
1630 l_ptr->max_pkt_probes = 0;
1631 }
1632
1633 max_pkt_ack = 0;
1634 if (msg_probe(msg)) {
1635 l_ptr->stats.recv_probes++;
1636 if (msg_size(msg) > sizeof(l_ptr->proto_msg))
1637 max_pkt_ack = msg_size(msg);
1638 }
1639
1640 /* Protocol message before retransmits, reduce loss risk */
1641 if (l_ptr->owner->bclink.recv_permitted)
1642 tipc_bclink_update_link_state(l_ptr->owner,
1643 msg_last_bcast(msg));
1644
1645 if (rec_gap || (msg_probe(msg))) {
1646 tipc_link_proto_xmit(l_ptr, STATE_MSG, 0, rec_gap, 0,
1647 0, max_pkt_ack);
1648 }
1649 if (msg_seq_gap(msg)) {
1650 l_ptr->stats.recv_nacks++;
1651 tipc_link_retransmit(l_ptr, l_ptr->first_out,
1652 msg_seq_gap(msg));
1653 }
1654 break;
1655 }
1656 exit:
1657 kfree_skb(buf);
1658 }
1659
1660
1661 /* tipc_link_tunnel_xmit(): Tunnel one packet via a link belonging to
1662 * a different bearer. Owner node is locked.
1663 */
1664 static void tipc_link_tunnel_xmit(struct tipc_link *l_ptr,
1665 struct tipc_msg *tunnel_hdr,
1666 struct tipc_msg *msg,
1667 u32 selector)
1668 {
1669 struct tipc_link *tunnel;
1670 struct sk_buff *buf;
1671 u32 length = msg_size(msg);
1672
1673 tunnel = l_ptr->owner->active_links[selector & 1];
1674 if (!tipc_link_is_up(tunnel)) {
1675 pr_warn("%stunnel link no longer available\n", link_co_err);
1676 return;
1677 }
1678 msg_set_size(tunnel_hdr, length + INT_H_SIZE);
1679 buf = tipc_buf_acquire(length + INT_H_SIZE);
1680 if (!buf) {
1681 pr_warn("%sunable to send tunnel msg\n", link_co_err);
1682 return;
1683 }
1684 skb_copy_to_linear_data(buf, tunnel_hdr, INT_H_SIZE);
1685 skb_copy_to_linear_data_offset(buf, INT_H_SIZE, msg, length);
1686 __tipc_link_xmit(tunnel, buf);
1687 }
1688
1689
1690 /* tipc_link_failover_send_queue(): A link has gone down, but a second
1691 * link is still active. We can do failover. Tunnel the failing link's
1692 * whole send queue via the remaining link. This way, we don't lose
1693 * any packets, and sequence order is preserved for subsequent traffic
1694 * sent over the remaining link. Owner node is locked.
1695 */
1696 void tipc_link_failover_send_queue(struct tipc_link *l_ptr)
1697 {
1698 u32 msgcount = l_ptr->out_queue_size;
1699 struct sk_buff *crs = l_ptr->first_out;
1700 struct tipc_link *tunnel = l_ptr->owner->active_links[0];
1701 struct tipc_msg tunnel_hdr;
1702 int split_bundles;
1703
1704 if (!tunnel)
1705 return;
1706
1707 tipc_msg_init(&tunnel_hdr, CHANGEOVER_PROTOCOL,
1708 ORIGINAL_MSG, INT_H_SIZE, l_ptr->addr);
1709 msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id);
1710 msg_set_msgcnt(&tunnel_hdr, msgcount);
1711
1712 if (!l_ptr->first_out) {
1713 struct sk_buff *buf;
1714
1715 buf = tipc_buf_acquire(INT_H_SIZE);
1716 if (buf) {
1717 skb_copy_to_linear_data(buf, &tunnel_hdr, INT_H_SIZE);
1718 msg_set_size(&tunnel_hdr, INT_H_SIZE);
1719 __tipc_link_xmit(tunnel, buf);
1720 } else {
1721 pr_warn("%sunable to send changeover msg\n",
1722 link_co_err);
1723 }
1724 return;
1725 }
1726
1727 split_bundles = (l_ptr->owner->active_links[0] !=
1728 l_ptr->owner->active_links[1]);
1729
1730 while (crs) {
1731 struct tipc_msg *msg = buf_msg(crs);
1732
1733 if ((msg_user(msg) == MSG_BUNDLER) && split_bundles) {
1734 struct tipc_msg *m = msg_get_wrapped(msg);
1735 unchar *pos = (unchar *)m;
1736
1737 msgcount = msg_msgcnt(msg);
1738 while (msgcount--) {
1739 msg_set_seqno(m, msg_seqno(msg));
1740 tipc_link_tunnel_xmit(l_ptr, &tunnel_hdr, m,
1741 msg_link_selector(m));
1742 pos += align(msg_size(m));
1743 m = (struct tipc_msg *)pos;
1744 }
1745 } else {
1746 tipc_link_tunnel_xmit(l_ptr, &tunnel_hdr, msg,
1747 msg_link_selector(msg));
1748 }
1749 crs = crs->next;
1750 }
1751 }
1752
1753 /* tipc_link_dup_queue_xmit(): A second link has become active. Tunnel a
1754 * duplicate of the first link's send queue via the new link. This way, we
1755 * are guaranteed that currently queued packets from a socket are delivered
1756 * before future traffic from the same socket, even if this is using the
1757 * new link. The last arriving copy of each duplicate packet is dropped at
1758 * the receiving end by the regular protocol check, so packet cardinality
1759 * and sequence order is preserved per sender/receiver socket pair.
1760 * Owner node is locked.
1761 */
1762 void tipc_link_dup_queue_xmit(struct tipc_link *l_ptr,
1763 struct tipc_link *tunnel)
1764 {
1765 struct sk_buff *iter;
1766 struct tipc_msg tunnel_hdr;
1767
1768 tipc_msg_init(&tunnel_hdr, CHANGEOVER_PROTOCOL,
1769 DUPLICATE_MSG, INT_H_SIZE, l_ptr->addr);
1770 msg_set_msgcnt(&tunnel_hdr, l_ptr->out_queue_size);
1771 msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id);
1772 iter = l_ptr->first_out;
1773 while (iter) {
1774 struct sk_buff *outbuf;
1775 struct tipc_msg *msg = buf_msg(iter);
1776 u32 length = msg_size(msg);
1777
1778 if (msg_user(msg) == MSG_BUNDLER)
1779 msg_set_type(msg, CLOSED_MSG);
1780 msg_set_ack(msg, mod(l_ptr->next_in_no - 1)); /* Update */
1781 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1782 msg_set_size(&tunnel_hdr, length + INT_H_SIZE);
1783 outbuf = tipc_buf_acquire(length + INT_H_SIZE);
1784 if (outbuf == NULL) {
1785 pr_warn("%sunable to send duplicate msg\n",
1786 link_co_err);
1787 return;
1788 }
1789 skb_copy_to_linear_data(outbuf, &tunnel_hdr, INT_H_SIZE);
1790 skb_copy_to_linear_data_offset(outbuf, INT_H_SIZE, iter->data,
1791 length);
1792 __tipc_link_xmit(tunnel, outbuf);
1793 if (!tipc_link_is_up(l_ptr))
1794 return;
1795 iter = iter->next;
1796 }
1797 }
1798
1799 /**
1800 * buf_extract - extracts embedded TIPC message from another message
1801 * @skb: encapsulating message buffer
1802 * @from_pos: offset to extract from
1803 *
1804 * Returns a new message buffer containing an embedded message. The
1805 * encapsulating message itself is left unchanged.
1806 */
1807 static struct sk_buff *buf_extract(struct sk_buff *skb, u32 from_pos)
1808 {
1809 struct tipc_msg *msg = (struct tipc_msg *)(skb->data + from_pos);
1810 u32 size = msg_size(msg);
1811 struct sk_buff *eb;
1812
1813 eb = tipc_buf_acquire(size);
1814 if (eb)
1815 skb_copy_to_linear_data(eb, msg, size);
1816 return eb;
1817 }
1818
1819
1820
1821 /* tipc_link_dup_rcv(): Receive a tunnelled DUPLICATE_MSG packet.
1822 * Owner node is locked.
1823 */
1824 static void tipc_link_dup_rcv(struct tipc_link *l_ptr,
1825 struct sk_buff *t_buf)
1826 {
1827 struct sk_buff *buf;
1828
1829 if (!tipc_link_is_up(l_ptr))
1830 return;
1831
1832 buf = buf_extract(t_buf, INT_H_SIZE);
1833 if (buf == NULL) {
1834 pr_warn("%sfailed to extract inner dup pkt\n", link_co_err);
1835 return;
1836 }
1837
1838 /* Add buffer to deferred queue, if applicable: */
1839 link_handle_out_of_seq_msg(l_ptr, buf);
1840 }
1841
1842 /* tipc_link_failover_rcv(): Receive a tunnelled ORIGINAL_MSG packet
1843 * Owner node is locked.
1844 */
1845 static struct sk_buff *tipc_link_failover_rcv(struct tipc_link *l_ptr,
1846 struct sk_buff *t_buf)
1847 {
1848 struct tipc_msg *t_msg = buf_msg(t_buf);
1849 struct sk_buff *buf = NULL;
1850 struct tipc_msg *msg;
1851
1852 if (tipc_link_is_up(l_ptr))
1853 tipc_link_reset(l_ptr);
1854
1855 /* First failover packet? */
1856 if (l_ptr->exp_msg_count == START_CHANGEOVER)
1857 l_ptr->exp_msg_count = msg_msgcnt(t_msg);
1858
1859 /* Should there be an inner packet? */
1860 if (l_ptr->exp_msg_count) {
1861 l_ptr->exp_msg_count--;
1862 buf = buf_extract(t_buf, INT_H_SIZE);
1863 if (buf == NULL) {
1864 pr_warn("%sno inner failover pkt\n", link_co_err);
1865 goto exit;
1866 }
1867 msg = buf_msg(buf);
1868
1869 if (less(msg_seqno(msg), l_ptr->reset_checkpoint)) {
1870 kfree_skb(buf);
1871 buf = NULL;
1872 goto exit;
1873 }
1874 if (msg_user(msg) == MSG_FRAGMENTER) {
1875 l_ptr->stats.recv_fragments++;
1876 tipc_buf_append(&l_ptr->reasm_buf, &buf);
1877 }
1878 }
1879 exit:
1880 if ((l_ptr->exp_msg_count == 0) && (l_ptr->flags & LINK_STOPPED)) {
1881 tipc_node_detach_link(l_ptr->owner, l_ptr);
1882 kfree(l_ptr);
1883 }
1884 return buf;
1885 }
1886
1887 /* tipc_link_tunnel_rcv(): Receive a tunnelled packet, sent
1888 * via other link as result of a failover (ORIGINAL_MSG) or
1889 * a new active link (DUPLICATE_MSG). Failover packets are
1890 * returned to the active link for delivery upwards.
1891 * Owner node is locked.
1892 */
1893 static int tipc_link_tunnel_rcv(struct tipc_node *n_ptr,
1894 struct sk_buff **buf)
1895 {
1896 struct sk_buff *t_buf = *buf;
1897 struct tipc_link *l_ptr;
1898 struct tipc_msg *t_msg = buf_msg(t_buf);
1899 u32 bearer_id = msg_bearer_id(t_msg);
1900
1901 *buf = NULL;
1902
1903 if (bearer_id >= MAX_BEARERS)
1904 goto exit;
1905
1906 l_ptr = n_ptr->links[bearer_id];
1907 if (!l_ptr)
1908 goto exit;
1909
1910 if (msg_type(t_msg) == DUPLICATE_MSG)
1911 tipc_link_dup_rcv(l_ptr, t_buf);
1912 else if (msg_type(t_msg) == ORIGINAL_MSG)
1913 *buf = tipc_link_failover_rcv(l_ptr, t_buf);
1914 else
1915 pr_warn("%sunknown tunnel pkt received\n", link_co_err);
1916 exit:
1917 kfree_skb(t_buf);
1918 return *buf != NULL;
1919 }
1920
1921 /*
1922 * Bundler functionality:
1923 */
1924 void tipc_link_bundle_rcv(struct sk_buff *buf)
1925 {
1926 u32 msgcount = msg_msgcnt(buf_msg(buf));
1927 u32 pos = INT_H_SIZE;
1928 struct sk_buff *obuf;
1929 struct tipc_msg *omsg;
1930
1931 while (msgcount--) {
1932 obuf = buf_extract(buf, pos);
1933 if (obuf == NULL) {
1934 pr_warn("Link unable to unbundle message(s)\n");
1935 break;
1936 }
1937 omsg = buf_msg(obuf);
1938 pos += align(msg_size(omsg));
1939 if (msg_isdata(omsg) || (msg_user(omsg) == CONN_MANAGER)) {
1940 tipc_sk_rcv(obuf);
1941 } else if (msg_user(omsg) == NAME_DISTRIBUTOR) {
1942 tipc_named_rcv(obuf);
1943 } else {
1944 pr_warn("Illegal bundled msg: %u\n", msg_user(omsg));
1945 kfree_skb(obuf);
1946 }
1947 }
1948 kfree_skb(buf);
1949 }
1950
1951 static void link_set_supervision_props(struct tipc_link *l_ptr, u32 tolerance)
1952 {
1953 if ((tolerance < TIPC_MIN_LINK_TOL) || (tolerance > TIPC_MAX_LINK_TOL))
1954 return;
1955
1956 l_ptr->tolerance = tolerance;
1957 l_ptr->continuity_interval =
1958 ((tolerance / 4) > 500) ? 500 : tolerance / 4;
1959 l_ptr->abort_limit = tolerance / (l_ptr->continuity_interval / 4);
1960 }
1961
1962 void tipc_link_set_queue_limits(struct tipc_link *l_ptr, u32 window)
1963 {
1964 /* Data messages from this node, inclusive FIRST_FRAGM */
1965 l_ptr->queue_limit[TIPC_LOW_IMPORTANCE] = window;
1966 l_ptr->queue_limit[TIPC_MEDIUM_IMPORTANCE] = (window / 3) * 4;
1967 l_ptr->queue_limit[TIPC_HIGH_IMPORTANCE] = (window / 3) * 5;
1968 l_ptr->queue_limit[TIPC_CRITICAL_IMPORTANCE] = (window / 3) * 6;
1969 /* Transiting data messages,inclusive FIRST_FRAGM */
1970 l_ptr->queue_limit[TIPC_LOW_IMPORTANCE + 4] = 300;
1971 l_ptr->queue_limit[TIPC_MEDIUM_IMPORTANCE + 4] = 600;
1972 l_ptr->queue_limit[TIPC_HIGH_IMPORTANCE + 4] = 900;
1973 l_ptr->queue_limit[TIPC_CRITICAL_IMPORTANCE + 4] = 1200;
1974 l_ptr->queue_limit[CONN_MANAGER] = 1200;
1975 l_ptr->queue_limit[CHANGEOVER_PROTOCOL] = 2500;
1976 l_ptr->queue_limit[NAME_DISTRIBUTOR] = 3000;
1977 /* FRAGMENT and LAST_FRAGMENT packets */
1978 l_ptr->queue_limit[MSG_FRAGMENTER] = 4000;
1979 }
1980
1981 /* tipc_link_find_owner - locate owner node of link by link's name
1982 * @name: pointer to link name string
1983 * @bearer_id: pointer to index in 'node->links' array where the link was found.
1984 *
1985 * Returns pointer to node owning the link, or 0 if no matching link is found.
1986 */
1987 static struct tipc_node *tipc_link_find_owner(const char *link_name,
1988 unsigned int *bearer_id)
1989 {
1990 struct tipc_link *l_ptr;
1991 struct tipc_node *n_ptr;
1992 struct tipc_node *found_node = 0;
1993 int i;
1994
1995 *bearer_id = 0;
1996 rcu_read_lock();
1997 list_for_each_entry_rcu(n_ptr, &tipc_node_list, list) {
1998 tipc_node_lock(n_ptr);
1999 for (i = 0; i < MAX_BEARERS; i++) {
2000 l_ptr = n_ptr->links[i];
2001 if (l_ptr && !strcmp(l_ptr->name, link_name)) {
2002 *bearer_id = i;
2003 found_node = n_ptr;
2004 break;
2005 }
2006 }
2007 tipc_node_unlock(n_ptr);
2008 if (found_node)
2009 break;
2010 }
2011 rcu_read_unlock();
2012
2013 return found_node;
2014 }
2015
2016 /**
2017 * link_value_is_valid -- validate proposed link tolerance/priority/window
2018 *
2019 * @cmd: value type (TIPC_CMD_SET_LINK_*)
2020 * @new_value: the new value
2021 *
2022 * Returns 1 if value is within range, 0 if not.
2023 */
2024 static int link_value_is_valid(u16 cmd, u32 new_value)
2025 {
2026 switch (cmd) {
2027 case TIPC_CMD_SET_LINK_TOL:
2028 return (new_value >= TIPC_MIN_LINK_TOL) &&
2029 (new_value <= TIPC_MAX_LINK_TOL);
2030 case TIPC_CMD_SET_LINK_PRI:
2031 return (new_value <= TIPC_MAX_LINK_PRI);
2032 case TIPC_CMD_SET_LINK_WINDOW:
2033 return (new_value >= TIPC_MIN_LINK_WIN) &&
2034 (new_value <= TIPC_MAX_LINK_WIN);
2035 }
2036 return 0;
2037 }
2038
2039 /**
2040 * link_cmd_set_value - change priority/tolerance/window for link/bearer/media
2041 * @name: ptr to link, bearer, or media name
2042 * @new_value: new value of link, bearer, or media setting
2043 * @cmd: which link, bearer, or media attribute to set (TIPC_CMD_SET_LINK_*)
2044 *
2045 * Caller must hold RTNL lock to ensure link/bearer/media is not deleted.
2046 *
2047 * Returns 0 if value updated and negative value on error.
2048 */
2049 static int link_cmd_set_value(const char *name, u32 new_value, u16 cmd)
2050 {
2051 struct tipc_node *node;
2052 struct tipc_link *l_ptr;
2053 struct tipc_bearer *b_ptr;
2054 struct tipc_media *m_ptr;
2055 int bearer_id;
2056 int res = 0;
2057
2058 node = tipc_link_find_owner(name, &bearer_id);
2059 if (node) {
2060 tipc_node_lock(node);
2061 l_ptr = node->links[bearer_id];
2062
2063 if (l_ptr) {
2064 switch (cmd) {
2065 case TIPC_CMD_SET_LINK_TOL:
2066 link_set_supervision_props(l_ptr, new_value);
2067 tipc_link_proto_xmit(l_ptr, STATE_MSG, 0, 0,
2068 new_value, 0, 0);
2069 break;
2070 case TIPC_CMD_SET_LINK_PRI:
2071 l_ptr->priority = new_value;
2072 tipc_link_proto_xmit(l_ptr, STATE_MSG, 0, 0,
2073 0, new_value, 0);
2074 break;
2075 case TIPC_CMD_SET_LINK_WINDOW:
2076 tipc_link_set_queue_limits(l_ptr, new_value);
2077 break;
2078 default:
2079 res = -EINVAL;
2080 break;
2081 }
2082 }
2083 tipc_node_unlock(node);
2084 return res;
2085 }
2086
2087 b_ptr = tipc_bearer_find(name);
2088 if (b_ptr) {
2089 switch (cmd) {
2090 case TIPC_CMD_SET_LINK_TOL:
2091 b_ptr->tolerance = new_value;
2092 break;
2093 case TIPC_CMD_SET_LINK_PRI:
2094 b_ptr->priority = new_value;
2095 break;
2096 case TIPC_CMD_SET_LINK_WINDOW:
2097 b_ptr->window = new_value;
2098 break;
2099 default:
2100 res = -EINVAL;
2101 break;
2102 }
2103 return res;
2104 }
2105
2106 m_ptr = tipc_media_find(name);
2107 if (!m_ptr)
2108 return -ENODEV;
2109 switch (cmd) {
2110 case TIPC_CMD_SET_LINK_TOL:
2111 m_ptr->tolerance = new_value;
2112 break;
2113 case TIPC_CMD_SET_LINK_PRI:
2114 m_ptr->priority = new_value;
2115 break;
2116 case TIPC_CMD_SET_LINK_WINDOW:
2117 m_ptr->window = new_value;
2118 break;
2119 default:
2120 res = -EINVAL;
2121 break;
2122 }
2123 return res;
2124 }
2125
2126 struct sk_buff *tipc_link_cmd_config(const void *req_tlv_area, int req_tlv_space,
2127 u16 cmd)
2128 {
2129 struct tipc_link_config *args;
2130 u32 new_value;
2131 int res;
2132
2133 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_CONFIG))
2134 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
2135
2136 args = (struct tipc_link_config *)TLV_DATA(req_tlv_area);
2137 new_value = ntohl(args->value);
2138
2139 if (!link_value_is_valid(cmd, new_value))
2140 return tipc_cfg_reply_error_string(
2141 "cannot change, value invalid");
2142
2143 if (!strcmp(args->name, tipc_bclink_name)) {
2144 if ((cmd == TIPC_CMD_SET_LINK_WINDOW) &&
2145 (tipc_bclink_set_queue_limits(new_value) == 0))
2146 return tipc_cfg_reply_none();
2147 return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED
2148 " (cannot change setting on broadcast link)");
2149 }
2150
2151 res = link_cmd_set_value(args->name, new_value, cmd);
2152 if (res)
2153 return tipc_cfg_reply_error_string("cannot change link setting");
2154
2155 return tipc_cfg_reply_none();
2156 }
2157
2158 /**
2159 * link_reset_statistics - reset link statistics
2160 * @l_ptr: pointer to link
2161 */
2162 static void link_reset_statistics(struct tipc_link *l_ptr)
2163 {
2164 memset(&l_ptr->stats, 0, sizeof(l_ptr->stats));
2165 l_ptr->stats.sent_info = l_ptr->next_out_no;
2166 l_ptr->stats.recv_info = l_ptr->next_in_no;
2167 }
2168
2169 struct sk_buff *tipc_link_cmd_reset_stats(const void *req_tlv_area, int req_tlv_space)
2170 {
2171 char *link_name;
2172 struct tipc_link *l_ptr;
2173 struct tipc_node *node;
2174 unsigned int bearer_id;
2175
2176 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_NAME))
2177 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
2178
2179 link_name = (char *)TLV_DATA(req_tlv_area);
2180 if (!strcmp(link_name, tipc_bclink_name)) {
2181 if (tipc_bclink_reset_stats())
2182 return tipc_cfg_reply_error_string("link not found");
2183 return tipc_cfg_reply_none();
2184 }
2185 node = tipc_link_find_owner(link_name, &bearer_id);
2186 if (!node)
2187 return tipc_cfg_reply_error_string("link not found");
2188
2189 tipc_node_lock(node);
2190 l_ptr = node->links[bearer_id];
2191 if (!l_ptr) {
2192 tipc_node_unlock(node);
2193 return tipc_cfg_reply_error_string("link not found");
2194 }
2195 link_reset_statistics(l_ptr);
2196 tipc_node_unlock(node);
2197 return tipc_cfg_reply_none();
2198 }
2199
2200 /**
2201 * percent - convert count to a percentage of total (rounding up or down)
2202 */
2203 static u32 percent(u32 count, u32 total)
2204 {
2205 return (count * 100 + (total / 2)) / total;
2206 }
2207
2208 /**
2209 * tipc_link_stats - print link statistics
2210 * @name: link name
2211 * @buf: print buffer area
2212 * @buf_size: size of print buffer area
2213 *
2214 * Returns length of print buffer data string (or 0 if error)
2215 */
2216 static int tipc_link_stats(const char *name, char *buf, const u32 buf_size)
2217 {
2218 struct tipc_link *l;
2219 struct tipc_stats *s;
2220 struct tipc_node *node;
2221 char *status;
2222 u32 profile_total = 0;
2223 unsigned int bearer_id;
2224 int ret;
2225
2226 if (!strcmp(name, tipc_bclink_name))
2227 return tipc_bclink_stats(buf, buf_size);
2228
2229 node = tipc_link_find_owner(name, &bearer_id);
2230 if (!node)
2231 return 0;
2232
2233 tipc_node_lock(node);
2234
2235 l = node->links[bearer_id];
2236 if (!l) {
2237 tipc_node_unlock(node);
2238 return 0;
2239 }
2240
2241 s = &l->stats;
2242
2243 if (tipc_link_is_active(l))
2244 status = "ACTIVE";
2245 else if (tipc_link_is_up(l))
2246 status = "STANDBY";
2247 else
2248 status = "DEFUNCT";
2249
2250 ret = tipc_snprintf(buf, buf_size, "Link <%s>\n"
2251 " %s MTU:%u Priority:%u Tolerance:%u ms"
2252 " Window:%u packets\n",
2253 l->name, status, l->max_pkt, l->priority,
2254 l->tolerance, l->queue_limit[0]);
2255
2256 ret += tipc_snprintf(buf + ret, buf_size - ret,
2257 " RX packets:%u fragments:%u/%u bundles:%u/%u\n",
2258 l->next_in_no - s->recv_info, s->recv_fragments,
2259 s->recv_fragmented, s->recv_bundles,
2260 s->recv_bundled);
2261
2262 ret += tipc_snprintf(buf + ret, buf_size - ret,
2263 " TX packets:%u fragments:%u/%u bundles:%u/%u\n",
2264 l->next_out_no - s->sent_info, s->sent_fragments,
2265 s->sent_fragmented, s->sent_bundles,
2266 s->sent_bundled);
2267
2268 profile_total = s->msg_length_counts;
2269 if (!profile_total)
2270 profile_total = 1;
2271
2272 ret += tipc_snprintf(buf + ret, buf_size - ret,
2273 " TX profile sample:%u packets average:%u octets\n"
2274 " 0-64:%u%% -256:%u%% -1024:%u%% -4096:%u%% "
2275 "-16384:%u%% -32768:%u%% -66000:%u%%\n",
2276 s->msg_length_counts,
2277 s->msg_lengths_total / profile_total,
2278 percent(s->msg_length_profile[0], profile_total),
2279 percent(s->msg_length_profile[1], profile_total),
2280 percent(s->msg_length_profile[2], profile_total),
2281 percent(s->msg_length_profile[3], profile_total),
2282 percent(s->msg_length_profile[4], profile_total),
2283 percent(s->msg_length_profile[5], profile_total),
2284 percent(s->msg_length_profile[6], profile_total));
2285
2286 ret += tipc_snprintf(buf + ret, buf_size - ret,
2287 " RX states:%u probes:%u naks:%u defs:%u"
2288 " dups:%u\n", s->recv_states, s->recv_probes,
2289 s->recv_nacks, s->deferred_recv, s->duplicates);
2290
2291 ret += tipc_snprintf(buf + ret, buf_size - ret,
2292 " TX states:%u probes:%u naks:%u acks:%u"
2293 " dups:%u\n", s->sent_states, s->sent_probes,
2294 s->sent_nacks, s->sent_acks, s->retransmitted);
2295
2296 ret += tipc_snprintf(buf + ret, buf_size - ret,
2297 " Congestion link:%u Send queue"
2298 " max:%u avg:%u\n", s->link_congs,
2299 s->max_queue_sz, s->queue_sz_counts ?
2300 (s->accu_queue_sz / s->queue_sz_counts) : 0);
2301
2302 tipc_node_unlock(node);
2303 return ret;
2304 }
2305
2306 struct sk_buff *tipc_link_cmd_show_stats(const void *req_tlv_area, int req_tlv_space)
2307 {
2308 struct sk_buff *buf;
2309 struct tlv_desc *rep_tlv;
2310 int str_len;
2311 int pb_len;
2312 char *pb;
2313
2314 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_NAME))
2315 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
2316
2317 buf = tipc_cfg_reply_alloc(TLV_SPACE(ULTRA_STRING_MAX_LEN));
2318 if (!buf)
2319 return NULL;
2320
2321 rep_tlv = (struct tlv_desc *)buf->data;
2322 pb = TLV_DATA(rep_tlv);
2323 pb_len = ULTRA_STRING_MAX_LEN;
2324 str_len = tipc_link_stats((char *)TLV_DATA(req_tlv_area),
2325 pb, pb_len);
2326 if (!str_len) {
2327 kfree_skb(buf);
2328 return tipc_cfg_reply_error_string("link not found");
2329 }
2330 str_len += 1; /* for "\0" */
2331 skb_put(buf, TLV_SPACE(str_len));
2332 TLV_SET(rep_tlv, TIPC_TLV_ULTRA_STRING, NULL, str_len);
2333
2334 return buf;
2335 }
2336
2337 /**
2338 * tipc_link_get_max_pkt - get maximum packet size to use when sending to destination
2339 * @dest: network address of destination node
2340 * @selector: used to select from set of active links
2341 *
2342 * If no active link can be found, uses default maximum packet size.
2343 */
2344 u32 tipc_link_get_max_pkt(u32 dest, u32 selector)
2345 {
2346 struct tipc_node *n_ptr;
2347 struct tipc_link *l_ptr;
2348 u32 res = MAX_PKT_DEFAULT;
2349
2350 if (dest == tipc_own_addr)
2351 return MAX_MSG_SIZE;
2352
2353 n_ptr = tipc_node_find(dest);
2354 if (n_ptr) {
2355 tipc_node_lock(n_ptr);
2356 l_ptr = n_ptr->active_links[selector & 1];
2357 if (l_ptr)
2358 res = l_ptr->max_pkt;
2359 tipc_node_unlock(n_ptr);
2360 }
2361 return res;
2362 }
2363
2364 static void link_print(struct tipc_link *l_ptr, const char *str)
2365 {
2366 struct tipc_bearer *b_ptr;
2367
2368 rcu_read_lock();
2369 b_ptr = rcu_dereference_rtnl(bearer_list[l_ptr->bearer_id]);
2370 if (b_ptr)
2371 pr_info("%s Link %x<%s>:", str, l_ptr->addr, b_ptr->name);
2372 rcu_read_unlock();
2373
2374 if (link_working_unknown(l_ptr))
2375 pr_cont(":WU\n");
2376 else if (link_reset_reset(l_ptr))
2377 pr_cont(":RR\n");
2378 else if (link_reset_unknown(l_ptr))
2379 pr_cont(":RU\n");
2380 else if (link_working_working(l_ptr))
2381 pr_cont(":WW\n");
2382 else
2383 pr_cont("\n");
2384 }
Linux kernel - Deliverables
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