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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 "name_distr.h"
41#include "discover.h"
42#include "config.h"
43
44#include <linux/pkt_sched.h>
45
46/*
47 * Error message prefixes
48 */
49static const char *link_co_err = "Link changeover error, ";
50static const char *link_rst_msg = "Resetting link ";
51static const char *link_unk_evt = "Unknown link event ";
52
53/*
54 * Out-of-range value for link session numbers
55 */
56#define INVALID_SESSION 0x10000
57
58/*
59 * Link state events:
60 */
61#define STARTING_EVT 856384768 /* link processing trigger */
62#define TRAFFIC_MSG_EVT 560815u /* rx'd ??? */
63#define TIMEOUT_EVT 560817u /* link timer expired */
64
65/*
66 * The following two 'message types' is really just implementation
67 * data conveniently stored in the message header.
68 * They must not be considered part of the protocol
69 */
70#define OPEN_MSG 0
71#define CLOSED_MSG 1
72
73/*
74 * State value stored in 'exp_msg_count'
75 */
76#define START_CHANGEOVER 100000u
77
78static void link_handle_out_of_seq_msg(struct tipc_link *l_ptr,
79 struct sk_buff *buf);
80static void tipc_link_proto_rcv(struct tipc_link *l_ptr, struct sk_buff *buf);
81static int tipc_link_tunnel_rcv(struct tipc_node *n_ptr,
82 struct sk_buff **buf);
83static void link_set_supervision_props(struct tipc_link *l_ptr, u32 tolerance);
84static int tipc_link_iovec_long_xmit(struct tipc_port *sender,
85 struct iovec const *msg_sect,
86 unsigned int len, u32 destnode);
87static void link_state_event(struct tipc_link *l_ptr, u32 event);
88static void link_reset_statistics(struct tipc_link *l_ptr);
89static void link_print(struct tipc_link *l_ptr, const char *str);
90static int tipc_link_frag_xmit(struct tipc_link *l_ptr, struct sk_buff *buf);
91static void tipc_link_sync_xmit(struct tipc_link *l);
92static void tipc_link_sync_rcv(struct tipc_node *n, struct sk_buff *buf);
93
94/*
95 * Simple link routines
96 */
97static unsigned int align(unsigned int i)
98{
99 return (i + 3) & ~3u;
100}
101
102static void link_init_max_pkt(struct tipc_link *l_ptr)
103{
104 u32 max_pkt;
105
106 max_pkt = (l_ptr->b_ptr->mtu & ~3);
107 if (max_pkt > MAX_MSG_SIZE)
108 max_pkt = MAX_MSG_SIZE;
109
110 l_ptr->max_pkt_target = max_pkt;
111 if (l_ptr->max_pkt_target < MAX_PKT_DEFAULT)
112 l_ptr->max_pkt = l_ptr->max_pkt_target;
113 else
114 l_ptr->max_pkt = MAX_PKT_DEFAULT;
115
116 l_ptr->max_pkt_probes = 0;
117}
118
119static u32 link_next_sent(struct tipc_link *l_ptr)
120{
121 if (l_ptr->next_out)
122 return buf_seqno(l_ptr->next_out);
123 return mod(l_ptr->next_out_no);
124}
125
126static u32 link_last_sent(struct tipc_link *l_ptr)
127{
128 return mod(link_next_sent(l_ptr) - 1);
129}
130
131/*
132 * Simple non-static link routines (i.e. referenced outside this file)
133 */
134int tipc_link_is_up(struct tipc_link *l_ptr)
135{
136 if (!l_ptr)
137 return 0;
138 return link_working_working(l_ptr) || link_working_unknown(l_ptr);
139}
140
141int tipc_link_is_active(struct tipc_link *l_ptr)
142{
143 return (l_ptr->owner->active_links[0] == l_ptr) ||
144 (l_ptr->owner->active_links[1] == l_ptr);
145}
146
147/**
148 * link_timeout - handle expiration of link timer
149 * @l_ptr: pointer to link
150 */
151static void link_timeout(struct tipc_link *l_ptr)
152{
153 tipc_node_lock(l_ptr->owner);
154
155 /* update counters used in statistical profiling of send traffic */
156 l_ptr->stats.accu_queue_sz += l_ptr->out_queue_size;
157 l_ptr->stats.queue_sz_counts++;
158
159 if (l_ptr->first_out) {
160 struct tipc_msg *msg = buf_msg(l_ptr->first_out);
161 u32 length = msg_size(msg);
162
163 if ((msg_user(msg) == MSG_FRAGMENTER) &&
164 (msg_type(msg) == FIRST_FRAGMENT)) {
165 length = msg_size(msg_get_wrapped(msg));
166 }
167 if (length) {
168 l_ptr->stats.msg_lengths_total += length;
169 l_ptr->stats.msg_length_counts++;
170 if (length <= 64)
171 l_ptr->stats.msg_length_profile[0]++;
172 else if (length <= 256)
173 l_ptr->stats.msg_length_profile[1]++;
174 else if (length <= 1024)
175 l_ptr->stats.msg_length_profile[2]++;
176 else if (length <= 4096)
177 l_ptr->stats.msg_length_profile[3]++;
178 else if (length <= 16384)
179 l_ptr->stats.msg_length_profile[4]++;
180 else if (length <= 32768)
181 l_ptr->stats.msg_length_profile[5]++;
182 else
183 l_ptr->stats.msg_length_profile[6]++;
184 }
185 }
186
187 /* do all other link processing performed on a periodic basis */
188
189 link_state_event(l_ptr, TIMEOUT_EVT);
190
191 if (l_ptr->next_out)
192 tipc_link_push_queue(l_ptr);
193
194 tipc_node_unlock(l_ptr->owner);
195}
196
197static void link_set_timer(struct tipc_link *l_ptr, u32 time)
198{
199 k_start_timer(&l_ptr->timer, time);
200}
201
202/**
203 * tipc_link_create - create a new link
204 * @n_ptr: pointer to associated node
205 * @b_ptr: pointer to associated bearer
206 * @media_addr: media address to use when sending messages over link
207 *
208 * Returns pointer to link.
209 */
210struct tipc_link *tipc_link_create(struct tipc_node *n_ptr,
211 struct tipc_bearer *b_ptr,
212 const struct tipc_media_addr *media_addr)
213{
214 struct tipc_link *l_ptr;
215 struct tipc_msg *msg;
216 char *if_name;
217 char addr_string[16];
218 u32 peer = n_ptr->addr;
219
220 if (n_ptr->link_cnt >= 2) {
221 tipc_addr_string_fill(addr_string, n_ptr->addr);
222 pr_err("Attempt to establish third link to %s\n", addr_string);
223 return NULL;
224 }
225
226 if (n_ptr->links[b_ptr->identity]) {
227 tipc_addr_string_fill(addr_string, n_ptr->addr);
228 pr_err("Attempt to establish second link on <%s> to %s\n",
229 b_ptr->name, addr_string);
230 return NULL;
231 }
232
233 l_ptr = kzalloc(sizeof(*l_ptr), GFP_ATOMIC);
234 if (!l_ptr) {
235 pr_warn("Link creation failed, no memory\n");
236 return NULL;
237 }
238
239 l_ptr->addr = peer;
240 if_name = strchr(b_ptr->name, ':') + 1;
241 sprintf(l_ptr->name, "%u.%u.%u:%s-%u.%u.%u:unknown",
242 tipc_zone(tipc_own_addr), tipc_cluster(tipc_own_addr),
243 tipc_node(tipc_own_addr),
244 if_name,
245 tipc_zone(peer), tipc_cluster(peer), tipc_node(peer));
246 /* note: peer i/f name is updated by reset/activate message */
247 memcpy(&l_ptr->media_addr, media_addr, sizeof(*media_addr));
248 l_ptr->owner = n_ptr;
249 l_ptr->checkpoint = 1;
250 l_ptr->peer_session = INVALID_SESSION;
251 l_ptr->b_ptr = b_ptr;
252 link_set_supervision_props(l_ptr, b_ptr->tolerance);
253 l_ptr->state = RESET_UNKNOWN;
254
255 l_ptr->pmsg = (struct tipc_msg *)&l_ptr->proto_msg;
256 msg = l_ptr->pmsg;
257 tipc_msg_init(msg, LINK_PROTOCOL, RESET_MSG, INT_H_SIZE, l_ptr->addr);
258 msg_set_size(msg, sizeof(l_ptr->proto_msg));
259 msg_set_session(msg, (tipc_random & 0xffff));
260 msg_set_bearer_id(msg, b_ptr->identity);
261 strcpy((char *)msg_data(msg), if_name);
262
263 l_ptr->priority = b_ptr->priority;
264 tipc_link_set_queue_limits(l_ptr, b_ptr->window);
265
266 link_init_max_pkt(l_ptr);
267
268 l_ptr->next_out_no = 1;
269 INIT_LIST_HEAD(&l_ptr->waiting_ports);
270
271 link_reset_statistics(l_ptr);
272
273 tipc_node_attach_link(n_ptr, l_ptr);
274
275 k_init_timer(&l_ptr->timer, (Handler)link_timeout,
276 (unsigned long)l_ptr);
277
278 link_state_event(l_ptr, STARTING_EVT);
279
280 return l_ptr;
281}
282
283void tipc_link_delete_list(unsigned int bearer_id, bool shutting_down)
284{
285 struct tipc_link *l_ptr;
286 struct tipc_node *n_ptr;
287
288 rcu_read_lock();
289 list_for_each_entry_rcu(n_ptr, &tipc_node_list, list) {
290 spin_lock_bh(&n_ptr->lock);
291 l_ptr = n_ptr->links[bearer_id];
292 if (l_ptr) {
293 tipc_link_reset(l_ptr);
294 if (shutting_down || !tipc_node_is_up(n_ptr)) {
295 tipc_node_detach_link(l_ptr->owner, l_ptr);
296 tipc_link_reset_fragments(l_ptr);
297 spin_unlock_bh(&n_ptr->lock);
298
299 /* Nobody else can access this link now: */
300 del_timer_sync(&l_ptr->timer);
301 kfree(l_ptr);
302 } else {
303 /* Detach/delete when failover is finished: */
304 l_ptr->flags |= LINK_STOPPED;
305 spin_unlock_bh(&n_ptr->lock);
306 del_timer_sync(&l_ptr->timer);
307 }
308 continue;
309 }
310 spin_unlock_bh(&n_ptr->lock);
311 }
312 rcu_read_unlock();
313}
314
315/**
316 * link_schedule_port - schedule port for deferred sending
317 * @l_ptr: pointer to link
318 * @origport: reference to sending port
319 * @sz: amount of data to be sent
320 *
321 * Schedules port for renewed sending of messages after link congestion
322 * has abated.
323 */
324static int link_schedule_port(struct tipc_link *l_ptr, u32 origport, u32 sz)
325{
326 struct tipc_port *p_ptr;
327
328 spin_lock_bh(&tipc_port_list_lock);
329 p_ptr = tipc_port_lock(origport);
330 if (p_ptr) {
331 if (!list_empty(&p_ptr->wait_list))
332 goto exit;
333 p_ptr->congested = 1;
334 p_ptr->waiting_pkts = 1 + ((sz - 1) / l_ptr->max_pkt);
335 list_add_tail(&p_ptr->wait_list, &l_ptr->waiting_ports);
336 l_ptr->stats.link_congs++;
337exit:
338 tipc_port_unlock(p_ptr);
339 }
340 spin_unlock_bh(&tipc_port_list_lock);
341 return -ELINKCONG;
342}
343
344void tipc_link_wakeup_ports(struct tipc_link *l_ptr, int all)
345{
346 struct tipc_port *p_ptr;
347 struct tipc_port *temp_p_ptr;
348 int win = l_ptr->queue_limit[0] - l_ptr->out_queue_size;
349
350 if (all)
351 win = 100000;
352 if (win <= 0)
353 return;
354 if (!spin_trylock_bh(&tipc_port_list_lock))
355 return;
356 if (link_congested(l_ptr))
357 goto exit;
358 list_for_each_entry_safe(p_ptr, temp_p_ptr, &l_ptr->waiting_ports,
359 wait_list) {
360 if (win <= 0)
361 break;
362 list_del_init(&p_ptr->wait_list);
363 spin_lock_bh(p_ptr->lock);
364 p_ptr->congested = 0;
365 tipc_port_wakeup(p_ptr);
366 win -= p_ptr->waiting_pkts;
367 spin_unlock_bh(p_ptr->lock);
368 }
369
370exit:
371 spin_unlock_bh(&tipc_port_list_lock);
372}
373
374/**
375 * link_release_outqueue - purge link's outbound message queue
376 * @l_ptr: pointer to link
377 */
378static void link_release_outqueue(struct tipc_link *l_ptr)
379{
380 kfree_skb_list(l_ptr->first_out);
381 l_ptr->first_out = NULL;
382 l_ptr->out_queue_size = 0;
383}
384
385/**
386 * tipc_link_reset_fragments - purge link's inbound message fragments queue
387 * @l_ptr: pointer to link
388 */
389void tipc_link_reset_fragments(struct tipc_link *l_ptr)
390{
391 kfree_skb(l_ptr->reasm_head);
392 l_ptr->reasm_head = NULL;
393 l_ptr->reasm_tail = NULL;
394}
395
396/**
397 * tipc_link_purge_queues - purge all pkt queues associated with link
398 * @l_ptr: pointer to link
399 */
400void tipc_link_purge_queues(struct tipc_link *l_ptr)
401{
402 kfree_skb_list(l_ptr->oldest_deferred_in);
403 kfree_skb_list(l_ptr->first_out);
404 tipc_link_reset_fragments(l_ptr);
405 kfree_skb(l_ptr->proto_msg_queue);
406 l_ptr->proto_msg_queue = NULL;
407}
408
409void tipc_link_reset(struct tipc_link *l_ptr)
410{
411 u32 prev_state = l_ptr->state;
412 u32 checkpoint = l_ptr->next_in_no;
413 int was_active_link = tipc_link_is_active(l_ptr);
414
415 msg_set_session(l_ptr->pmsg, ((msg_session(l_ptr->pmsg) + 1) & 0xffff));
416
417 /* Link is down, accept any session */
418 l_ptr->peer_session = INVALID_SESSION;
419
420 /* Prepare for max packet size negotiation */
421 link_init_max_pkt(l_ptr);
422
423 l_ptr->state = RESET_UNKNOWN;
424
425 if ((prev_state == RESET_UNKNOWN) || (prev_state == RESET_RESET))
426 return;
427
428 tipc_node_link_down(l_ptr->owner, l_ptr);
429 tipc_bearer_remove_dest(l_ptr->b_ptr, l_ptr->addr);
430
431 if (was_active_link && tipc_node_active_links(l_ptr->owner)) {
432 l_ptr->reset_checkpoint = checkpoint;
433 l_ptr->exp_msg_count = START_CHANGEOVER;
434 }
435
436 /* Clean up all queues: */
437 link_release_outqueue(l_ptr);
438 kfree_skb(l_ptr->proto_msg_queue);
439 l_ptr->proto_msg_queue = NULL;
440 kfree_skb_list(l_ptr->oldest_deferred_in);
441 if (!list_empty(&l_ptr->waiting_ports))
442 tipc_link_wakeup_ports(l_ptr, 1);
443
444 l_ptr->retransm_queue_head = 0;
445 l_ptr->retransm_queue_size = 0;
446 l_ptr->last_out = NULL;
447 l_ptr->first_out = NULL;
448 l_ptr->next_out = NULL;
449 l_ptr->unacked_window = 0;
450 l_ptr->checkpoint = 1;
451 l_ptr->next_out_no = 1;
452 l_ptr->deferred_inqueue_sz = 0;
453 l_ptr->oldest_deferred_in = NULL;
454 l_ptr->newest_deferred_in = NULL;
455 l_ptr->fsm_msg_cnt = 0;
456 l_ptr->stale_count = 0;
457 link_reset_statistics(l_ptr);
458}
459
460void tipc_link_reset_list(unsigned int bearer_id)
461{
462 struct tipc_link *l_ptr;
463 struct tipc_node *n_ptr;
464
465 rcu_read_lock();
466 list_for_each_entry_rcu(n_ptr, &tipc_node_list, list) {
467 spin_lock_bh(&n_ptr->lock);
468 l_ptr = n_ptr->links[bearer_id];
469 if (l_ptr)
470 tipc_link_reset(l_ptr);
471 spin_unlock_bh(&n_ptr->lock);
472 }
473 rcu_read_unlock();
474}
475
476static void link_activate(struct tipc_link *l_ptr)
477{
478 l_ptr->next_in_no = l_ptr->stats.recv_info = 1;
479 tipc_node_link_up(l_ptr->owner, l_ptr);
480 tipc_bearer_add_dest(l_ptr->b_ptr, l_ptr->addr);
481}
482
483/**
484 * link_state_event - link finite state machine
485 * @l_ptr: pointer to link
486 * @event: state machine event to process
487 */
488static void link_state_event(struct tipc_link *l_ptr, unsigned int event)
489{
490 struct tipc_link *other;
491 u32 cont_intv = l_ptr->continuity_interval;
492
493 if (l_ptr->flags & LINK_STOPPED)
494 return;
495
496 if (!(l_ptr->flags & LINK_STARTED) && (event != STARTING_EVT))
497 return; /* Not yet. */
498
499 /* Check whether changeover is going on */
500 if (l_ptr->exp_msg_count) {
501 if (event == TIMEOUT_EVT)
502 link_set_timer(l_ptr, cont_intv);
503 return;
504 }
505
506 switch (l_ptr->state) {
507 case WORKING_WORKING:
508 switch (event) {
509 case TRAFFIC_MSG_EVT:
510 case ACTIVATE_MSG:
511 break;
512 case TIMEOUT_EVT:
513 if (l_ptr->next_in_no != l_ptr->checkpoint) {
514 l_ptr->checkpoint = l_ptr->next_in_no;
515 if (tipc_bclink_acks_missing(l_ptr->owner)) {
516 tipc_link_proto_xmit(l_ptr, STATE_MSG,
517 0, 0, 0, 0, 0);
518 l_ptr->fsm_msg_cnt++;
519 } else if (l_ptr->max_pkt < l_ptr->max_pkt_target) {
520 tipc_link_proto_xmit(l_ptr, STATE_MSG,
521 1, 0, 0, 0, 0);
522 l_ptr->fsm_msg_cnt++;
523 }
524 link_set_timer(l_ptr, cont_intv);
525 break;
526 }
527 l_ptr->state = WORKING_UNKNOWN;
528 l_ptr->fsm_msg_cnt = 0;
529 tipc_link_proto_xmit(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
530 l_ptr->fsm_msg_cnt++;
531 link_set_timer(l_ptr, cont_intv / 4);
532 break;
533 case RESET_MSG:
534 pr_info("%s<%s>, requested by peer\n", link_rst_msg,
535 l_ptr->name);
536 tipc_link_reset(l_ptr);
537 l_ptr->state = RESET_RESET;
538 l_ptr->fsm_msg_cnt = 0;
539 tipc_link_proto_xmit(l_ptr, ACTIVATE_MSG,
540 0, 0, 0, 0, 0);
541 l_ptr->fsm_msg_cnt++;
542 link_set_timer(l_ptr, cont_intv);
543 break;
544 default:
545 pr_err("%s%u in WW state\n", link_unk_evt, event);
546 }
547 break;
548 case WORKING_UNKNOWN:
549 switch (event) {
550 case TRAFFIC_MSG_EVT:
551 case ACTIVATE_MSG:
552 l_ptr->state = WORKING_WORKING;
553 l_ptr->fsm_msg_cnt = 0;
554 link_set_timer(l_ptr, cont_intv);
555 break;
556 case RESET_MSG:
557 pr_info("%s<%s>, requested by peer while probing\n",
558 link_rst_msg, l_ptr->name);
559 tipc_link_reset(l_ptr);
560 l_ptr->state = RESET_RESET;
561 l_ptr->fsm_msg_cnt = 0;
562 tipc_link_proto_xmit(l_ptr, ACTIVATE_MSG,
563 0, 0, 0, 0, 0);
564 l_ptr->fsm_msg_cnt++;
565 link_set_timer(l_ptr, cont_intv);
566 break;
567 case TIMEOUT_EVT:
568 if (l_ptr->next_in_no != l_ptr->checkpoint) {
569 l_ptr->state = WORKING_WORKING;
570 l_ptr->fsm_msg_cnt = 0;
571 l_ptr->checkpoint = l_ptr->next_in_no;
572 if (tipc_bclink_acks_missing(l_ptr->owner)) {
573 tipc_link_proto_xmit(l_ptr, STATE_MSG,
574 0, 0, 0, 0, 0);
575 l_ptr->fsm_msg_cnt++;
576 }
577 link_set_timer(l_ptr, cont_intv);
578 } else if (l_ptr->fsm_msg_cnt < l_ptr->abort_limit) {
579 tipc_link_proto_xmit(l_ptr, STATE_MSG,
580 1, 0, 0, 0, 0);
581 l_ptr->fsm_msg_cnt++;
582 link_set_timer(l_ptr, cont_intv / 4);
583 } else { /* Link has failed */
584 pr_warn("%s<%s>, peer not responding\n",
585 link_rst_msg, l_ptr->name);
586 tipc_link_reset(l_ptr);
587 l_ptr->state = RESET_UNKNOWN;
588 l_ptr->fsm_msg_cnt = 0;
589 tipc_link_proto_xmit(l_ptr, RESET_MSG,
590 0, 0, 0, 0, 0);
591 l_ptr->fsm_msg_cnt++;
592 link_set_timer(l_ptr, cont_intv);
593 }
594 break;
595 default:
596 pr_err("%s%u in WU state\n", link_unk_evt, event);
597 }
598 break;
599 case RESET_UNKNOWN:
600 switch (event) {
601 case TRAFFIC_MSG_EVT:
602 break;
603 case ACTIVATE_MSG:
604 other = l_ptr->owner->active_links[0];
605 if (other && link_working_unknown(other))
606 break;
607 l_ptr->state = WORKING_WORKING;
608 l_ptr->fsm_msg_cnt = 0;
609 link_activate(l_ptr);
610 tipc_link_proto_xmit(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
611 l_ptr->fsm_msg_cnt++;
612 if (l_ptr->owner->working_links == 1)
613 tipc_link_sync_xmit(l_ptr);
614 link_set_timer(l_ptr, cont_intv);
615 break;
616 case RESET_MSG:
617 l_ptr->state = RESET_RESET;
618 l_ptr->fsm_msg_cnt = 0;
619 tipc_link_proto_xmit(l_ptr, ACTIVATE_MSG,
620 1, 0, 0, 0, 0);
621 l_ptr->fsm_msg_cnt++;
622 link_set_timer(l_ptr, cont_intv);
623 break;
624 case STARTING_EVT:
625 l_ptr->flags |= LINK_STARTED;
626 /* fall through */
627 case TIMEOUT_EVT:
628 tipc_link_proto_xmit(l_ptr, RESET_MSG, 0, 0, 0, 0, 0);
629 l_ptr->fsm_msg_cnt++;
630 link_set_timer(l_ptr, cont_intv);
631 break;
632 default:
633 pr_err("%s%u in RU state\n", link_unk_evt, event);
634 }
635 break;
636 case RESET_RESET:
637 switch (event) {
638 case TRAFFIC_MSG_EVT:
639 case ACTIVATE_MSG:
640 other = l_ptr->owner->active_links[0];
641 if (other && link_working_unknown(other))
642 break;
643 l_ptr->state = WORKING_WORKING;
644 l_ptr->fsm_msg_cnt = 0;
645 link_activate(l_ptr);
646 tipc_link_proto_xmit(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
647 l_ptr->fsm_msg_cnt++;
648 if (l_ptr->owner->working_links == 1)
649 tipc_link_sync_xmit(l_ptr);
650 link_set_timer(l_ptr, cont_intv);
651 break;
652 case RESET_MSG:
653 break;
654 case TIMEOUT_EVT:
655 tipc_link_proto_xmit(l_ptr, ACTIVATE_MSG,
656 0, 0, 0, 0, 0);
657 l_ptr->fsm_msg_cnt++;
658 link_set_timer(l_ptr, cont_intv);
659 break;
660 default:
661 pr_err("%s%u in RR state\n", link_unk_evt, event);
662 }
663 break;
664 default:
665 pr_err("Unknown link state %u/%u\n", l_ptr->state, event);
666 }
667}
668
669/*
670 * link_bundle_buf(): Append contents of a buffer to
671 * the tail of an existing one.
672 */
673static int link_bundle_buf(struct tipc_link *l_ptr, struct sk_buff *bundler,
674 struct sk_buff *buf)
675{
676 struct tipc_msg *bundler_msg = buf_msg(bundler);
677 struct tipc_msg *msg = buf_msg(buf);
678 u32 size = msg_size(msg);
679 u32 bundle_size = msg_size(bundler_msg);
680 u32 to_pos = align(bundle_size);
681 u32 pad = to_pos - bundle_size;
682
683 if (msg_user(bundler_msg) != MSG_BUNDLER)
684 return 0;
685 if (msg_type(bundler_msg) != OPEN_MSG)
686 return 0;
687 if (skb_tailroom(bundler) < (pad + size))
688 return 0;
689 if (l_ptr->max_pkt < (to_pos + size))
690 return 0;
691
692 skb_put(bundler, pad + size);
693 skb_copy_to_linear_data_offset(bundler, to_pos, buf->data, size);
694 msg_set_size(bundler_msg, to_pos + size);
695 msg_set_msgcnt(bundler_msg, msg_msgcnt(bundler_msg) + 1);
696 kfree_skb(buf);
697 l_ptr->stats.sent_bundled++;
698 return 1;
699}
700
701static void link_add_to_outqueue(struct tipc_link *l_ptr,
702 struct sk_buff *buf,
703 struct tipc_msg *msg)
704{
705 u32 ack = mod(l_ptr->next_in_no - 1);
706 u32 seqno = mod(l_ptr->next_out_no++);
707
708 msg_set_word(msg, 2, ((ack << 16) | seqno));
709 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
710 buf->next = NULL;
711 if (l_ptr->first_out) {
712 l_ptr->last_out->next = buf;
713 l_ptr->last_out = buf;
714 } else
715 l_ptr->first_out = l_ptr->last_out = buf;
716
717 l_ptr->out_queue_size++;
718 if (l_ptr->out_queue_size > l_ptr->stats.max_queue_sz)
719 l_ptr->stats.max_queue_sz = l_ptr->out_queue_size;
720}
721
722static void link_add_chain_to_outqueue(struct tipc_link *l_ptr,
723 struct sk_buff *buf_chain,
724 u32 long_msgno)
725{
726 struct sk_buff *buf;
727 struct tipc_msg *msg;
728
729 if (!l_ptr->next_out)
730 l_ptr->next_out = buf_chain;
731 while (buf_chain) {
732 buf = buf_chain;
733 buf_chain = buf_chain->next;
734
735 msg = buf_msg(buf);
736 msg_set_long_msgno(msg, long_msgno);
737 link_add_to_outqueue(l_ptr, buf, msg);
738 }
739}
740
741/*
742 * tipc_link_xmit() is the 'full path' for messages, called from
743 * inside TIPC when the 'fast path' in tipc_send_xmit
744 * has failed, and from link_send()
745 */
746int __tipc_link_xmit(struct tipc_link *l_ptr, struct sk_buff *buf)
747{
748 struct tipc_msg *msg = buf_msg(buf);
749 u32 size = msg_size(msg);
750 u32 dsz = msg_data_sz(msg);
751 u32 queue_size = l_ptr->out_queue_size;
752 u32 imp = tipc_msg_tot_importance(msg);
753 u32 queue_limit = l_ptr->queue_limit[imp];
754 u32 max_packet = l_ptr->max_pkt;
755
756 /* Match msg importance against queue limits: */
757 if (unlikely(queue_size >= queue_limit)) {
758 if (imp <= TIPC_CRITICAL_IMPORTANCE) {
759 link_schedule_port(l_ptr, msg_origport(msg), size);
760 kfree_skb(buf);
761 return -ELINKCONG;
762 }
763 kfree_skb(buf);
764 if (imp > CONN_MANAGER) {
765 pr_warn("%s<%s>, send queue full", link_rst_msg,
766 l_ptr->name);
767 tipc_link_reset(l_ptr);
768 }
769 return dsz;
770 }
771
772 /* Fragmentation needed ? */
773 if (size > max_packet)
774 return tipc_link_frag_xmit(l_ptr, buf);
775
776 /* Packet can be queued or sent. */
777 if (likely(!link_congested(l_ptr))) {
778 link_add_to_outqueue(l_ptr, buf, msg);
779
780 tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr);
781 l_ptr->unacked_window = 0;
782 return dsz;
783 }
784 /* Congestion: can message be bundled ? */
785 if ((msg_user(msg) != CHANGEOVER_PROTOCOL) &&
786 (msg_user(msg) != MSG_FRAGMENTER)) {
787
788 /* Try adding message to an existing bundle */
789 if (l_ptr->next_out &&
790 link_bundle_buf(l_ptr, l_ptr->last_out, buf))
791 return dsz;
792
793 /* Try creating a new bundle */
794 if (size <= max_packet * 2 / 3) {
795 struct sk_buff *bundler = tipc_buf_acquire(max_packet);
796 struct tipc_msg bundler_hdr;
797
798 if (bundler) {
799 tipc_msg_init(&bundler_hdr, MSG_BUNDLER, OPEN_MSG,
800 INT_H_SIZE, l_ptr->addr);
801 skb_copy_to_linear_data(bundler, &bundler_hdr,
802 INT_H_SIZE);
803 skb_trim(bundler, INT_H_SIZE);
804 link_bundle_buf(l_ptr, bundler, buf);
805 buf = bundler;
806 msg = buf_msg(buf);
807 l_ptr->stats.sent_bundles++;
808 }
809 }
810 }
811 if (!l_ptr->next_out)
812 l_ptr->next_out = buf;
813 link_add_to_outqueue(l_ptr, buf, msg);
814 return dsz;
815}
816
817/*
818 * tipc_link_xmit(): same as __tipc_link_xmit(), but the link to use
819 * has not been selected yet, and the the owner node is not locked
820 * Called by TIPC internal users, e.g. the name distributor
821 */
822int tipc_link_xmit(struct sk_buff *buf, u32 dest, u32 selector)
823{
824 struct tipc_link *l_ptr;
825 struct tipc_node *n_ptr;
826 int res = -ELINKCONG;
827
828 read_lock_bh(&tipc_net_lock);
829 n_ptr = tipc_node_find(dest);
830 if (n_ptr) {
831 tipc_node_lock(n_ptr);
832 l_ptr = n_ptr->active_links[selector & 1];
833 if (l_ptr)
834 res = __tipc_link_xmit(l_ptr, buf);
835 else
836 kfree_skb(buf);
837 tipc_node_unlock(n_ptr);
838 } else {
839 kfree_skb(buf);
840 }
841 read_unlock_bh(&tipc_net_lock);
842 return res;
843}
844
845/*
846 * tipc_link_sync_xmit - synchronize broadcast link endpoints.
847 *
848 * Give a newly added peer node the sequence number where it should
849 * start receiving and acking broadcast packets.
850 *
851 * Called with node locked
852 */
853static void tipc_link_sync_xmit(struct tipc_link *l)
854{
855 struct sk_buff *buf;
856 struct tipc_msg *msg;
857
858 buf = tipc_buf_acquire(INT_H_SIZE);
859 if (!buf)
860 return;
861
862 msg = buf_msg(buf);
863 tipc_msg_init(msg, BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE, l->addr);
864 msg_set_last_bcast(msg, l->owner->bclink.acked);
865 link_add_chain_to_outqueue(l, buf, 0);
866 tipc_link_push_queue(l);
867}
868
869/*
870 * tipc_link_sync_rcv - synchronize broadcast link endpoints.
871 * Receive the sequence number where we should start receiving and
872 * acking broadcast packets from a newly added peer node, and open
873 * up for reception of such packets.
874 *
875 * Called with node locked
876 */
877static void tipc_link_sync_rcv(struct tipc_node *n, struct sk_buff *buf)
878{
879 struct tipc_msg *msg = buf_msg(buf);
880
881 n->bclink.last_sent = n->bclink.last_in = msg_last_bcast(msg);
882 n->bclink.recv_permitted = true;
883 kfree_skb(buf);
884}
885
886/*
887 * tipc_link_names_xmit - send name table entries to new neighbor
888 *
889 * Send routine for bulk delivery of name table messages when contact
890 * with a new neighbor occurs. No link congestion checking is performed
891 * because name table messages *must* be delivered. The messages must be
892 * small enough not to require fragmentation.
893 * Called without any locks held.
894 */
895void tipc_link_names_xmit(struct list_head *message_list, u32 dest)
896{
897 struct tipc_node *n_ptr;
898 struct tipc_link *l_ptr;
899 struct sk_buff *buf;
900 struct sk_buff *temp_buf;
901
902 if (list_empty(message_list))
903 return;
904
905 read_lock_bh(&tipc_net_lock);
906 n_ptr = tipc_node_find(dest);
907 if (n_ptr) {
908 tipc_node_lock(n_ptr);
909 l_ptr = n_ptr->active_links[0];
910 if (l_ptr) {
911 /* convert circular list to linear list */
912 ((struct sk_buff *)message_list->prev)->next = NULL;
913 link_add_chain_to_outqueue(l_ptr,
914 (struct sk_buff *)message_list->next, 0);
915 tipc_link_push_queue(l_ptr);
916 INIT_LIST_HEAD(message_list);
917 }
918 tipc_node_unlock(n_ptr);
919 }
920 read_unlock_bh(&tipc_net_lock);
921
922 /* discard the messages if they couldn't be sent */
923 list_for_each_safe(buf, temp_buf, ((struct sk_buff *)message_list)) {
924 list_del((struct list_head *)buf);
925 kfree_skb(buf);
926 }
927}
928
929/*
930 * tipc_link_xmit_fast: Entry for data messages where the
931 * destination link is known and the header is complete,
932 * inclusive total message length. Very time critical.
933 * Link is locked. Returns user data length.
934 */
935static int tipc_link_xmit_fast(struct tipc_link *l_ptr, struct sk_buff *buf,
936 u32 *used_max_pkt)
937{
938 struct tipc_msg *msg = buf_msg(buf);
939 int res = msg_data_sz(msg);
940
941 if (likely(!link_congested(l_ptr))) {
942 if (likely(msg_size(msg) <= l_ptr->max_pkt)) {
943 link_add_to_outqueue(l_ptr, buf, msg);
944 tipc_bearer_send(l_ptr->b_ptr, buf,
945 &l_ptr->media_addr);
946 l_ptr->unacked_window = 0;
947 return res;
948 }
949 else
950 *used_max_pkt = l_ptr->max_pkt;
951 }
952 return __tipc_link_xmit(l_ptr, buf); /* All other cases */
953}
954
955/*
956 * tipc_link_iovec_xmit_fast: Entry for messages where the
957 * destination processor is known and the header is complete,
958 * except for total message length.
959 * Returns user data length or errno.
960 */
961int tipc_link_iovec_xmit_fast(struct tipc_port *sender,
962 struct iovec const *msg_sect,
963 unsigned int len, u32 destaddr)
964{
965 struct tipc_msg *hdr = &sender->phdr;
966 struct tipc_link *l_ptr;
967 struct sk_buff *buf;
968 struct tipc_node *node;
969 int res;
970 u32 selector = msg_origport(hdr) & 1;
971
972again:
973 /*
974 * Try building message using port's max_pkt hint.
975 * (Must not hold any locks while building message.)
976 */
977 res = tipc_msg_build(hdr, msg_sect, len, sender->max_pkt, &buf);
978 /* Exit if build request was invalid */
979 if (unlikely(res < 0))
980 return res;
981
982 read_lock_bh(&tipc_net_lock);
983 node = tipc_node_find(destaddr);
984 if (likely(node)) {
985 tipc_node_lock(node);
986 l_ptr = node->active_links[selector];
987 if (likely(l_ptr)) {
988 if (likely(buf)) {
989 res = tipc_link_xmit_fast(l_ptr, buf,
990 &sender->max_pkt);
991exit:
992 tipc_node_unlock(node);
993 read_unlock_bh(&tipc_net_lock);
994 return res;
995 }
996
997 /* Exit if link (or bearer) is congested */
998 if (link_congested(l_ptr)) {
999 res = link_schedule_port(l_ptr,
1000 sender->ref, res);
1001 goto exit;
1002 }
1003
1004 /*
1005 * Message size exceeds max_pkt hint; update hint,
1006 * then re-try fast path or fragment the message
1007 */
1008 sender->max_pkt = l_ptr->max_pkt;
1009 tipc_node_unlock(node);
1010 read_unlock_bh(&tipc_net_lock);
1011
1012
1013 if ((msg_hdr_sz(hdr) + res) <= sender->max_pkt)
1014 goto again;
1015
1016 return tipc_link_iovec_long_xmit(sender, msg_sect,
1017 len, destaddr);
1018 }
1019 tipc_node_unlock(node);
1020 }
1021 read_unlock_bh(&tipc_net_lock);
1022
1023 /* Couldn't find a link to the destination node */
1024 kfree_skb(buf);
1025 tipc_port_iovec_reject(sender, hdr, msg_sect, len, TIPC_ERR_NO_NODE);
1026 return -ENETUNREACH;
1027}
1028
1029/*
1030 * tipc_link_iovec_long_xmit(): Entry for long messages where the
1031 * destination node is known and the header is complete,
1032 * inclusive total message length.
1033 * Link and bearer congestion status have been checked to be ok,
1034 * and are ignored if they change.
1035 *
1036 * Note that fragments do not use the full link MTU so that they won't have
1037 * to undergo refragmentation if link changeover causes them to be sent
1038 * over another link with an additional tunnel header added as prefix.
1039 * (Refragmentation will still occur if the other link has a smaller MTU.)
1040 *
1041 * Returns user data length or errno.
1042 */
1043static int tipc_link_iovec_long_xmit(struct tipc_port *sender,
1044 struct iovec const *msg_sect,
1045 unsigned int len, u32 destaddr)
1046{
1047 struct tipc_link *l_ptr;
1048 struct tipc_node *node;
1049 struct tipc_msg *hdr = &sender->phdr;
1050 u32 dsz = len;
1051 u32 max_pkt, fragm_sz, rest;
1052 struct tipc_msg fragm_hdr;
1053 struct sk_buff *buf, *buf_chain, *prev;
1054 u32 fragm_crs, fragm_rest, hsz, sect_rest;
1055 const unchar __user *sect_crs;
1056 int curr_sect;
1057 u32 fragm_no;
1058 int res = 0;
1059
1060again:
1061 fragm_no = 1;
1062 max_pkt = sender->max_pkt - INT_H_SIZE;
1063 /* leave room for tunnel header in case of link changeover */
1064 fragm_sz = max_pkt - INT_H_SIZE;
1065 /* leave room for fragmentation header in each fragment */
1066 rest = dsz;
1067 fragm_crs = 0;
1068 fragm_rest = 0;
1069 sect_rest = 0;
1070 sect_crs = NULL;
1071 curr_sect = -1;
1072
1073 /* Prepare reusable fragment header */
1074 tipc_msg_init(&fragm_hdr, MSG_FRAGMENTER, FIRST_FRAGMENT,
1075 INT_H_SIZE, msg_destnode(hdr));
1076 msg_set_size(&fragm_hdr, max_pkt);
1077 msg_set_fragm_no(&fragm_hdr, 1);
1078
1079 /* Prepare header of first fragment */
1080 buf_chain = buf = tipc_buf_acquire(max_pkt);
1081 if (!buf)
1082 return -ENOMEM;
1083 buf->next = NULL;
1084 skb_copy_to_linear_data(buf, &fragm_hdr, INT_H_SIZE);
1085 hsz = msg_hdr_sz(hdr);
1086 skb_copy_to_linear_data_offset(buf, INT_H_SIZE, hdr, hsz);
1087
1088 /* Chop up message */
1089 fragm_crs = INT_H_SIZE + hsz;
1090 fragm_rest = fragm_sz - hsz;
1091
1092 do { /* For all sections */
1093 u32 sz;
1094
1095 if (!sect_rest) {
1096 sect_rest = msg_sect[++curr_sect].iov_len;
1097 sect_crs = msg_sect[curr_sect].iov_base;
1098 }
1099
1100 if (sect_rest < fragm_rest)
1101 sz = sect_rest;
1102 else
1103 sz = fragm_rest;
1104
1105 if (copy_from_user(buf->data + fragm_crs, sect_crs, sz)) {
1106 res = -EFAULT;
1107error:
1108 kfree_skb_list(buf_chain);
1109 return res;
1110 }
1111 sect_crs += sz;
1112 sect_rest -= sz;
1113 fragm_crs += sz;
1114 fragm_rest -= sz;
1115 rest -= sz;
1116
1117 if (!fragm_rest && rest) {
1118
1119 /* Initiate new fragment: */
1120 if (rest <= fragm_sz) {
1121 fragm_sz = rest;
1122 msg_set_type(&fragm_hdr, LAST_FRAGMENT);
1123 } else {
1124 msg_set_type(&fragm_hdr, FRAGMENT);
1125 }
1126 msg_set_size(&fragm_hdr, fragm_sz + INT_H_SIZE);
1127 msg_set_fragm_no(&fragm_hdr, ++fragm_no);
1128 prev = buf;
1129 buf = tipc_buf_acquire(fragm_sz + INT_H_SIZE);
1130 if (!buf) {
1131 res = -ENOMEM;
1132 goto error;
1133 }
1134
1135 buf->next = NULL;
1136 prev->next = buf;
1137 skb_copy_to_linear_data(buf, &fragm_hdr, INT_H_SIZE);
1138 fragm_crs = INT_H_SIZE;
1139 fragm_rest = fragm_sz;
1140 }
1141 } while (rest > 0);
1142
1143 /*
1144 * Now we have a buffer chain. Select a link and check
1145 * that packet size is still OK
1146 */
1147 node = tipc_node_find(destaddr);
1148 if (likely(node)) {
1149 tipc_node_lock(node);
1150 l_ptr = node->active_links[sender->ref & 1];
1151 if (!l_ptr) {
1152 tipc_node_unlock(node);
1153 goto reject;
1154 }
1155 if (l_ptr->max_pkt < max_pkt) {
1156 sender->max_pkt = l_ptr->max_pkt;
1157 tipc_node_unlock(node);
1158 kfree_skb_list(buf_chain);
1159 goto again;
1160 }
1161 } else {
1162reject:
1163 kfree_skb_list(buf_chain);
1164 tipc_port_iovec_reject(sender, hdr, msg_sect, len,
1165 TIPC_ERR_NO_NODE);
1166 return -ENETUNREACH;
1167 }
1168
1169 /* Append chain of fragments to send queue & send them */
1170 l_ptr->long_msg_seq_no++;
1171 link_add_chain_to_outqueue(l_ptr, buf_chain, l_ptr->long_msg_seq_no);
1172 l_ptr->stats.sent_fragments += fragm_no;
1173 l_ptr->stats.sent_fragmented++;
1174 tipc_link_push_queue(l_ptr);
1175 tipc_node_unlock(node);
1176 return dsz;
1177}
1178
1179/*
1180 * tipc_link_push_packet: Push one unsent packet to the media
1181 */
1182static u32 tipc_link_push_packet(struct tipc_link *l_ptr)
1183{
1184 struct sk_buff *buf = l_ptr->first_out;
1185 u32 r_q_size = l_ptr->retransm_queue_size;
1186 u32 r_q_head = l_ptr->retransm_queue_head;
1187
1188 /* Step to position where retransmission failed, if any, */
1189 /* consider that buffers may have been released in meantime */
1190 if (r_q_size && buf) {
1191 u32 last = lesser(mod(r_q_head + r_q_size),
1192 link_last_sent(l_ptr));
1193 u32 first = buf_seqno(buf);
1194
1195 while (buf && less(first, r_q_head)) {
1196 first = mod(first + 1);
1197 buf = buf->next;
1198 }
1199 l_ptr->retransm_queue_head = r_q_head = first;
1200 l_ptr->retransm_queue_size = r_q_size = mod(last - first);
1201 }
1202
1203 /* Continue retransmission now, if there is anything: */
1204 if (r_q_size && buf) {
1205 msg_set_ack(buf_msg(buf), mod(l_ptr->next_in_no - 1));
1206 msg_set_bcast_ack(buf_msg(buf), l_ptr->owner->bclink.last_in);
1207 tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr);
1208 l_ptr->retransm_queue_head = mod(++r_q_head);
1209 l_ptr->retransm_queue_size = --r_q_size;
1210 l_ptr->stats.retransmitted++;
1211 return 0;
1212 }
1213
1214 /* Send deferred protocol message, if any: */
1215 buf = l_ptr->proto_msg_queue;
1216 if (buf) {
1217 msg_set_ack(buf_msg(buf), mod(l_ptr->next_in_no - 1));
1218 msg_set_bcast_ack(buf_msg(buf), l_ptr->owner->bclink.last_in);
1219 tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr);
1220 l_ptr->unacked_window = 0;
1221 kfree_skb(buf);
1222 l_ptr->proto_msg_queue = NULL;
1223 return 0;
1224 }
1225
1226 /* Send one deferred data message, if send window not full: */
1227 buf = l_ptr->next_out;
1228 if (buf) {
1229 struct tipc_msg *msg = buf_msg(buf);
1230 u32 next = msg_seqno(msg);
1231 u32 first = buf_seqno(l_ptr->first_out);
1232
1233 if (mod(next - first) < l_ptr->queue_limit[0]) {
1234 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
1235 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1236 tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr);
1237 if (msg_user(msg) == MSG_BUNDLER)
1238 msg_set_type(msg, CLOSED_MSG);
1239 l_ptr->next_out = buf->next;
1240 return 0;
1241 }
1242 }
1243 return 1;
1244}
1245
1246/*
1247 * push_queue(): push out the unsent messages of a link where
1248 * congestion has abated. Node is locked
1249 */
1250void tipc_link_push_queue(struct tipc_link *l_ptr)
1251{
1252 u32 res;
1253
1254 do {
1255 res = tipc_link_push_packet(l_ptr);
1256 } while (!res);
1257}
1258
1259static void link_reset_all(unsigned long addr)
1260{
1261 struct tipc_node *n_ptr;
1262 char addr_string[16];
1263 u32 i;
1264
1265 read_lock_bh(&tipc_net_lock);
1266 n_ptr = tipc_node_find((u32)addr);
1267 if (!n_ptr) {
1268 read_unlock_bh(&tipc_net_lock);
1269 return; /* node no longer exists */
1270 }
1271
1272 tipc_node_lock(n_ptr);
1273
1274 pr_warn("Resetting all links to %s\n",
1275 tipc_addr_string_fill(addr_string, n_ptr->addr));
1276
1277 for (i = 0; i < MAX_BEARERS; i++) {
1278 if (n_ptr->links[i]) {
1279 link_print(n_ptr->links[i], "Resetting link\n");
1280 tipc_link_reset(n_ptr->links[i]);
1281 }
1282 }
1283
1284 tipc_node_unlock(n_ptr);
1285 read_unlock_bh(&tipc_net_lock);
1286}
1287
1288static void link_retransmit_failure(struct tipc_link *l_ptr,
1289 struct sk_buff *buf)
1290{
1291 struct tipc_msg *msg = buf_msg(buf);
1292
1293 pr_warn("Retransmission failure on link <%s>\n", l_ptr->name);
1294
1295 if (l_ptr->addr) {
1296 /* Handle failure on standard link */
1297 link_print(l_ptr, "Resetting link\n");
1298 tipc_link_reset(l_ptr);
1299
1300 } else {
1301 /* Handle failure on broadcast link */
1302 struct tipc_node *n_ptr;
1303 char addr_string[16];
1304
1305 pr_info("Msg seq number: %u, ", msg_seqno(msg));
1306 pr_cont("Outstanding acks: %lu\n",
1307 (unsigned long) TIPC_SKB_CB(buf)->handle);
1308
1309 n_ptr = tipc_bclink_retransmit_to();
1310 tipc_node_lock(n_ptr);
1311
1312 tipc_addr_string_fill(addr_string, n_ptr->addr);
1313 pr_info("Broadcast link info for %s\n", addr_string);
1314 pr_info("Reception permitted: %d, Acked: %u\n",
1315 n_ptr->bclink.recv_permitted,
1316 n_ptr->bclink.acked);
1317 pr_info("Last in: %u, Oos state: %u, Last sent: %u\n",
1318 n_ptr->bclink.last_in,
1319 n_ptr->bclink.oos_state,
1320 n_ptr->bclink.last_sent);
1321
1322 tipc_k_signal((Handler)link_reset_all, (unsigned long)n_ptr->addr);
1323
1324 tipc_node_unlock(n_ptr);
1325
1326 l_ptr->stale_count = 0;
1327 }
1328}
1329
1330void tipc_link_retransmit(struct tipc_link *l_ptr, struct sk_buff *buf,
1331 u32 retransmits)
1332{
1333 struct tipc_msg *msg;
1334
1335 if (!buf)
1336 return;
1337
1338 msg = buf_msg(buf);
1339
1340 /* Detect repeated retransmit failures */
1341 if (l_ptr->last_retransmitted == msg_seqno(msg)) {
1342 if (++l_ptr->stale_count > 100) {
1343 link_retransmit_failure(l_ptr, buf);
1344 return;
1345 }
1346 } else {
1347 l_ptr->last_retransmitted = msg_seqno(msg);
1348 l_ptr->stale_count = 1;
1349 }
1350
1351 while (retransmits && (buf != l_ptr->next_out) && buf) {
1352 msg = buf_msg(buf);
1353 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
1354 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1355 tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr);
1356 buf = buf->next;
1357 retransmits--;
1358 l_ptr->stats.retransmitted++;
1359 }
1360
1361 l_ptr->retransm_queue_head = l_ptr->retransm_queue_size = 0;
1362}
1363
1364/**
1365 * link_insert_deferred_queue - insert deferred messages back into receive chain
1366 */
1367static struct sk_buff *link_insert_deferred_queue(struct tipc_link *l_ptr,
1368 struct sk_buff *buf)
1369{
1370 u32 seq_no;
1371
1372 if (l_ptr->oldest_deferred_in == NULL)
1373 return buf;
1374
1375 seq_no = buf_seqno(l_ptr->oldest_deferred_in);
1376 if (seq_no == mod(l_ptr->next_in_no)) {
1377 l_ptr->newest_deferred_in->next = buf;
1378 buf = l_ptr->oldest_deferred_in;
1379 l_ptr->oldest_deferred_in = NULL;
1380 l_ptr->deferred_inqueue_sz = 0;
1381 }
1382 return buf;
1383}
1384
1385/**
1386 * link_recv_buf_validate - validate basic format of received message
1387 *
1388 * This routine ensures a TIPC message has an acceptable header, and at least
1389 * as much data as the header indicates it should. The routine also ensures
1390 * that the entire message header is stored in the main fragment of the message
1391 * buffer, to simplify future access to message header fields.
1392 *
1393 * Note: Having extra info present in the message header or data areas is OK.
1394 * TIPC will ignore the excess, under the assumption that it is optional info
1395 * introduced by a later release of the protocol.
1396 */
1397static int link_recv_buf_validate(struct sk_buff *buf)
1398{
1399 static u32 min_data_hdr_size[8] = {
1400 SHORT_H_SIZE, MCAST_H_SIZE, NAMED_H_SIZE, BASIC_H_SIZE,
1401 MAX_H_SIZE, MAX_H_SIZE, MAX_H_SIZE, MAX_H_SIZE
1402 };
1403
1404 struct tipc_msg *msg;
1405 u32 tipc_hdr[2];
1406 u32 size;
1407 u32 hdr_size;
1408 u32 min_hdr_size;
1409
1410 /* If this packet comes from the defer queue, the skb has already
1411 * been validated
1412 */
1413 if (unlikely(TIPC_SKB_CB(buf)->deferred))
1414 return 1;
1415
1416 if (unlikely(buf->len < MIN_H_SIZE))
1417 return 0;
1418
1419 msg = skb_header_pointer(buf, 0, sizeof(tipc_hdr), tipc_hdr);
1420 if (msg == NULL)
1421 return 0;
1422
1423 if (unlikely(msg_version(msg) != TIPC_VERSION))
1424 return 0;
1425
1426 size = msg_size(msg);
1427 hdr_size = msg_hdr_sz(msg);
1428 min_hdr_size = msg_isdata(msg) ?
1429 min_data_hdr_size[msg_type(msg)] : INT_H_SIZE;
1430
1431 if (unlikely((hdr_size < min_hdr_size) ||
1432 (size < hdr_size) ||
1433 (buf->len < size) ||
1434 (size - hdr_size > TIPC_MAX_USER_MSG_SIZE)))
1435 return 0;
1436
1437 return pskb_may_pull(buf, hdr_size);
1438}
1439
1440/**
1441 * tipc_rcv - process TIPC packets/messages arriving from off-node
1442 * @head: pointer to message buffer chain
1443 * @tb_ptr: pointer to bearer message arrived on
1444 *
1445 * Invoked with no locks held. Bearer pointer must point to a valid bearer
1446 * structure (i.e. cannot be NULL), but bearer can be inactive.
1447 */
1448void tipc_rcv(struct sk_buff *head, struct tipc_bearer *b_ptr)
1449{
1450 read_lock_bh(&tipc_net_lock);
1451 while (head) {
1452 struct tipc_node *n_ptr;
1453 struct tipc_link *l_ptr;
1454 struct sk_buff *crs;
1455 struct sk_buff *buf = head;
1456 struct tipc_msg *msg;
1457 u32 seq_no;
1458 u32 ackd;
1459 u32 released = 0;
1460
1461 head = head->next;
1462 buf->next = NULL;
1463
1464 /* Ensure message is well-formed */
1465 if (unlikely(!link_recv_buf_validate(buf)))
1466 goto discard;
1467
1468 /* Ensure message data is a single contiguous unit */
1469 if (unlikely(skb_linearize(buf)))
1470 goto discard;
1471
1472 /* Handle arrival of a non-unicast link message */
1473 msg = buf_msg(buf);
1474
1475 if (unlikely(msg_non_seq(msg))) {
1476 if (msg_user(msg) == LINK_CONFIG)
1477 tipc_disc_rcv(buf, b_ptr);
1478 else
1479 tipc_bclink_rcv(buf);
1480 continue;
1481 }
1482
1483 /* Discard unicast link messages destined for another node */
1484 if (unlikely(!msg_short(msg) &&
1485 (msg_destnode(msg) != tipc_own_addr)))
1486 goto discard;
1487
1488 /* Locate neighboring node that sent message */
1489 n_ptr = tipc_node_find(msg_prevnode(msg));
1490 if (unlikely(!n_ptr))
1491 goto discard;
1492 tipc_node_lock(n_ptr);
1493
1494 /* Locate unicast link endpoint that should handle message */
1495 l_ptr = n_ptr->links[b_ptr->identity];
1496 if (unlikely(!l_ptr))
1497 goto unlock_discard;
1498
1499 /* Verify that communication with node is currently allowed */
1500 if ((n_ptr->block_setup & WAIT_PEER_DOWN) &&
1501 msg_user(msg) == LINK_PROTOCOL &&
1502 (msg_type(msg) == RESET_MSG ||
1503 msg_type(msg) == ACTIVATE_MSG) &&
1504 !msg_redundant_link(msg))
1505 n_ptr->block_setup &= ~WAIT_PEER_DOWN;
1506
1507 if (n_ptr->block_setup)
1508 goto unlock_discard;
1509
1510 /* Validate message sequence number info */
1511 seq_no = msg_seqno(msg);
1512 ackd = msg_ack(msg);
1513
1514 /* Release acked messages */
1515 if (n_ptr->bclink.recv_permitted)
1516 tipc_bclink_acknowledge(n_ptr, msg_bcast_ack(msg));
1517
1518 crs = l_ptr->first_out;
1519 while ((crs != l_ptr->next_out) &&
1520 less_eq(buf_seqno(crs), ackd)) {
1521 struct sk_buff *next = crs->next;
1522 kfree_skb(crs);
1523 crs = next;
1524 released++;
1525 }
1526 if (released) {
1527 l_ptr->first_out = crs;
1528 l_ptr->out_queue_size -= released;
1529 }
1530
1531 /* Try sending any messages link endpoint has pending */
1532 if (unlikely(l_ptr->next_out))
1533 tipc_link_push_queue(l_ptr);
1534
1535 if (unlikely(!list_empty(&l_ptr->waiting_ports)))
1536 tipc_link_wakeup_ports(l_ptr, 0);
1537
1538 if (unlikely(++l_ptr->unacked_window >= TIPC_MIN_LINK_WIN)) {
1539 l_ptr->stats.sent_acks++;
1540 tipc_link_proto_xmit(l_ptr, STATE_MSG, 0, 0, 0, 0, 0);
1541 }
1542
1543 /* Process the incoming packet */
1544 if (unlikely(!link_working_working(l_ptr))) {
1545 if (msg_user(msg) == LINK_PROTOCOL) {
1546 tipc_link_proto_rcv(l_ptr, buf);
1547 head = link_insert_deferred_queue(l_ptr, head);
1548 tipc_node_unlock(n_ptr);
1549 continue;
1550 }
1551
1552 /* Traffic message. Conditionally activate link */
1553 link_state_event(l_ptr, TRAFFIC_MSG_EVT);
1554
1555 if (link_working_working(l_ptr)) {
1556 /* Re-insert buffer in front of queue */
1557 buf->next = head;
1558 head = buf;
1559 tipc_node_unlock(n_ptr);
1560 continue;
1561 }
1562 goto unlock_discard;
1563 }
1564
1565 /* Link is now in state WORKING_WORKING */
1566 if (unlikely(seq_no != mod(l_ptr->next_in_no))) {
1567 link_handle_out_of_seq_msg(l_ptr, buf);
1568 head = link_insert_deferred_queue(l_ptr, head);
1569 tipc_node_unlock(n_ptr);
1570 continue;
1571 }
1572 l_ptr->next_in_no++;
1573 if (unlikely(l_ptr->oldest_deferred_in))
1574 head = link_insert_deferred_queue(l_ptr, head);
1575
1576 /* Deliver packet/message to correct user: */
1577 if (unlikely(msg_user(msg) == CHANGEOVER_PROTOCOL)) {
1578 if (!tipc_link_tunnel_rcv(n_ptr, &buf)) {
1579 tipc_node_unlock(n_ptr);
1580 continue;
1581 }
1582 msg = buf_msg(buf);
1583 } else if (msg_user(msg) == MSG_FRAGMENTER) {
1584 int rc;
1585
1586 l_ptr->stats.recv_fragments++;
1587 rc = tipc_link_frag_rcv(&l_ptr->reasm_head,
1588 &l_ptr->reasm_tail,
1589 &buf);
1590 if (rc == LINK_REASM_COMPLETE) {
1591 l_ptr->stats.recv_fragmented++;
1592 msg = buf_msg(buf);
1593 } else {
1594 if (rc == LINK_REASM_ERROR)
1595 tipc_link_reset(l_ptr);
1596 tipc_node_unlock(n_ptr);
1597 continue;
1598 }
1599 }
1600
1601 switch (msg_user(msg)) {
1602 case TIPC_LOW_IMPORTANCE:
1603 case TIPC_MEDIUM_IMPORTANCE:
1604 case TIPC_HIGH_IMPORTANCE:
1605 case TIPC_CRITICAL_IMPORTANCE:
1606 tipc_node_unlock(n_ptr);
1607 tipc_port_rcv(buf);
1608 continue;
1609 case MSG_BUNDLER:
1610 l_ptr->stats.recv_bundles++;
1611 l_ptr->stats.recv_bundled += msg_msgcnt(msg);
1612 tipc_node_unlock(n_ptr);
1613 tipc_link_bundle_rcv(buf);
1614 continue;
1615 case NAME_DISTRIBUTOR:
1616 n_ptr->bclink.recv_permitted = true;
1617 tipc_node_unlock(n_ptr);
1618 tipc_named_rcv(buf);
1619 continue;
1620 case CONN_MANAGER:
1621 tipc_node_unlock(n_ptr);
1622 tipc_port_proto_rcv(buf);
1623 continue;
1624 case BCAST_PROTOCOL:
1625 tipc_link_sync_rcv(n_ptr, buf);
1626 break;
1627 default:
1628 kfree_skb(buf);
1629 break;
1630 }
1631 tipc_node_unlock(n_ptr);
1632 continue;
1633unlock_discard:
1634 tipc_node_unlock(n_ptr);
1635discard:
1636 kfree_skb(buf);
1637 }
1638 read_unlock_bh(&tipc_net_lock);
1639}
1640
1641/**
1642 * tipc_link_defer_pkt - Add out-of-sequence message to deferred reception queue
1643 *
1644 * Returns increase in queue length (i.e. 0 or 1)
1645 */
1646u32 tipc_link_defer_pkt(struct sk_buff **head, struct sk_buff **tail,
1647 struct sk_buff *buf)
1648{
1649 struct sk_buff *queue_buf;
1650 struct sk_buff **prev;
1651 u32 seq_no = buf_seqno(buf);
1652
1653 buf->next = NULL;
1654
1655 /* Empty queue ? */
1656 if (*head == NULL) {
1657 *head = *tail = buf;
1658 return 1;
1659 }
1660
1661 /* Last ? */
1662 if (less(buf_seqno(*tail), seq_no)) {
1663 (*tail)->next = buf;
1664 *tail = buf;
1665 return 1;
1666 }
1667
1668 /* Locate insertion point in queue, then insert; discard if duplicate */
1669 prev = head;
1670 queue_buf = *head;
1671 for (;;) {
1672 u32 curr_seqno = buf_seqno(queue_buf);
1673
1674 if (seq_no == curr_seqno) {
1675 kfree_skb(buf);
1676 return 0;
1677 }
1678
1679 if (less(seq_no, curr_seqno))
1680 break;
1681
1682 prev = &queue_buf->next;
1683 queue_buf = queue_buf->next;
1684 }
1685
1686 buf->next = queue_buf;
1687 *prev = buf;
1688 return 1;
1689}
1690
1691/*
1692 * link_handle_out_of_seq_msg - handle arrival of out-of-sequence packet
1693 */
1694static void link_handle_out_of_seq_msg(struct tipc_link *l_ptr,
1695 struct sk_buff *buf)
1696{
1697 u32 seq_no = buf_seqno(buf);
1698
1699 if (likely(msg_user(buf_msg(buf)) == LINK_PROTOCOL)) {
1700 tipc_link_proto_rcv(l_ptr, buf);
1701 return;
1702 }
1703
1704 /* Record OOS packet arrival (force mismatch on next timeout) */
1705 l_ptr->checkpoint--;
1706
1707 /*
1708 * Discard packet if a duplicate; otherwise add it to deferred queue
1709 * and notify peer of gap as per protocol specification
1710 */
1711 if (less(seq_no, mod(l_ptr->next_in_no))) {
1712 l_ptr->stats.duplicates++;
1713 kfree_skb(buf);
1714 return;
1715 }
1716
1717 if (tipc_link_defer_pkt(&l_ptr->oldest_deferred_in,
1718 &l_ptr->newest_deferred_in, buf)) {
1719 l_ptr->deferred_inqueue_sz++;
1720 l_ptr->stats.deferred_recv++;
1721 TIPC_SKB_CB(buf)->deferred = true;
1722 if ((l_ptr->deferred_inqueue_sz % 16) == 1)
1723 tipc_link_proto_xmit(l_ptr, STATE_MSG, 0, 0, 0, 0, 0);
1724 } else
1725 l_ptr->stats.duplicates++;
1726}
1727
1728/*
1729 * Send protocol message to the other endpoint.
1730 */
1731void tipc_link_proto_xmit(struct tipc_link *l_ptr, u32 msg_typ, int probe_msg,
1732 u32 gap, u32 tolerance, u32 priority, u32 ack_mtu)
1733{
1734 struct sk_buff *buf = NULL;
1735 struct tipc_msg *msg = l_ptr->pmsg;
1736 u32 msg_size = sizeof(l_ptr->proto_msg);
1737 int r_flag;
1738
1739 /* Discard any previous message that was deferred due to congestion */
1740 if (l_ptr->proto_msg_queue) {
1741 kfree_skb(l_ptr->proto_msg_queue);
1742 l_ptr->proto_msg_queue = NULL;
1743 }
1744
1745 /* Don't send protocol message during link changeover */
1746 if (l_ptr->exp_msg_count)
1747 return;
1748
1749 /* Abort non-RESET send if communication with node is prohibited */
1750 if ((l_ptr->owner->block_setup) && (msg_typ != RESET_MSG))
1751 return;
1752
1753 /* Create protocol message with "out-of-sequence" sequence number */
1754 msg_set_type(msg, msg_typ);
1755 msg_set_net_plane(msg, l_ptr->b_ptr->net_plane);
1756 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1757 msg_set_last_bcast(msg, tipc_bclink_get_last_sent());
1758
1759 if (msg_typ == STATE_MSG) {
1760 u32 next_sent = mod(l_ptr->next_out_no);
1761
1762 if (!tipc_link_is_up(l_ptr))
1763 return;
1764 if (l_ptr->next_out)
1765 next_sent = buf_seqno(l_ptr->next_out);
1766 msg_set_next_sent(msg, next_sent);
1767 if (l_ptr->oldest_deferred_in) {
1768 u32 rec = buf_seqno(l_ptr->oldest_deferred_in);
1769 gap = mod(rec - mod(l_ptr->next_in_no));
1770 }
1771 msg_set_seq_gap(msg, gap);
1772 if (gap)
1773 l_ptr->stats.sent_nacks++;
1774 msg_set_link_tolerance(msg, tolerance);
1775 msg_set_linkprio(msg, priority);
1776 msg_set_max_pkt(msg, ack_mtu);
1777 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
1778 msg_set_probe(msg, probe_msg != 0);
1779 if (probe_msg) {
1780 u32 mtu = l_ptr->max_pkt;
1781
1782 if ((mtu < l_ptr->max_pkt_target) &&
1783 link_working_working(l_ptr) &&
1784 l_ptr->fsm_msg_cnt) {
1785 msg_size = (mtu + (l_ptr->max_pkt_target - mtu)/2 + 2) & ~3;
1786 if (l_ptr->max_pkt_probes == 10) {
1787 l_ptr->max_pkt_target = (msg_size - 4);
1788 l_ptr->max_pkt_probes = 0;
1789 msg_size = (mtu + (l_ptr->max_pkt_target - mtu)/2 + 2) & ~3;
1790 }
1791 l_ptr->max_pkt_probes++;
1792 }
1793
1794 l_ptr->stats.sent_probes++;
1795 }
1796 l_ptr->stats.sent_states++;
1797 } else { /* RESET_MSG or ACTIVATE_MSG */
1798 msg_set_ack(msg, mod(l_ptr->reset_checkpoint - 1));
1799 msg_set_seq_gap(msg, 0);
1800 msg_set_next_sent(msg, 1);
1801 msg_set_probe(msg, 0);
1802 msg_set_link_tolerance(msg, l_ptr->tolerance);
1803 msg_set_linkprio(msg, l_ptr->priority);
1804 msg_set_max_pkt(msg, l_ptr->max_pkt_target);
1805 }
1806
1807 r_flag = (l_ptr->owner->working_links > tipc_link_is_up(l_ptr));
1808 msg_set_redundant_link(msg, r_flag);
1809 msg_set_linkprio(msg, l_ptr->priority);
1810 msg_set_size(msg, msg_size);
1811
1812 msg_set_seqno(msg, mod(l_ptr->next_out_no + (0xffff/2)));
1813
1814 buf = tipc_buf_acquire(msg_size);
1815 if (!buf)
1816 return;
1817
1818 skb_copy_to_linear_data(buf, msg, sizeof(l_ptr->proto_msg));
1819 buf->priority = TC_PRIO_CONTROL;
1820
1821 tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr);
1822 l_ptr->unacked_window = 0;
1823 kfree_skb(buf);
1824}
1825
1826/*
1827 * Receive protocol message :
1828 * Note that network plane id propagates through the network, and may
1829 * change at any time. The node with lowest address rules
1830 */
1831static void tipc_link_proto_rcv(struct tipc_link *l_ptr, struct sk_buff *buf)
1832{
1833 u32 rec_gap = 0;
1834 u32 max_pkt_info;
1835 u32 max_pkt_ack;
1836 u32 msg_tol;
1837 struct tipc_msg *msg = buf_msg(buf);
1838
1839 /* Discard protocol message during link changeover */
1840 if (l_ptr->exp_msg_count)
1841 goto exit;
1842
1843 /* record unnumbered packet arrival (force mismatch on next timeout) */
1844 l_ptr->checkpoint--;
1845
1846 if (l_ptr->b_ptr->net_plane != msg_net_plane(msg))
1847 if (tipc_own_addr > msg_prevnode(msg))
1848 l_ptr->b_ptr->net_plane = msg_net_plane(msg);
1849
1850 switch (msg_type(msg)) {
1851
1852 case RESET_MSG:
1853 if (!link_working_unknown(l_ptr) &&
1854 (l_ptr->peer_session != INVALID_SESSION)) {
1855 if (less_eq(msg_session(msg), l_ptr->peer_session))
1856 break; /* duplicate or old reset: ignore */
1857 }
1858
1859 if (!msg_redundant_link(msg) && (link_working_working(l_ptr) ||
1860 link_working_unknown(l_ptr))) {
1861 /*
1862 * peer has lost contact -- don't allow peer's links
1863 * to reactivate before we recognize loss & clean up
1864 */
1865 l_ptr->owner->block_setup = WAIT_NODE_DOWN;
1866 }
1867
1868 link_state_event(l_ptr, RESET_MSG);
1869
1870 /* fall thru' */
1871 case ACTIVATE_MSG:
1872 /* Update link settings according other endpoint's values */
1873 strcpy((strrchr(l_ptr->name, ':') + 1), (char *)msg_data(msg));
1874
1875 msg_tol = msg_link_tolerance(msg);
1876 if (msg_tol > l_ptr->tolerance)
1877 link_set_supervision_props(l_ptr, msg_tol);
1878
1879 if (msg_linkprio(msg) > l_ptr->priority)
1880 l_ptr->priority = msg_linkprio(msg);
1881
1882 max_pkt_info = msg_max_pkt(msg);
1883 if (max_pkt_info) {
1884 if (max_pkt_info < l_ptr->max_pkt_target)
1885 l_ptr->max_pkt_target = max_pkt_info;
1886 if (l_ptr->max_pkt > l_ptr->max_pkt_target)
1887 l_ptr->max_pkt = l_ptr->max_pkt_target;
1888 } else {
1889 l_ptr->max_pkt = l_ptr->max_pkt_target;
1890 }
1891
1892 /* Synchronize broadcast link info, if not done previously */
1893 if (!tipc_node_is_up(l_ptr->owner)) {
1894 l_ptr->owner->bclink.last_sent =
1895 l_ptr->owner->bclink.last_in =
1896 msg_last_bcast(msg);
1897 l_ptr->owner->bclink.oos_state = 0;
1898 }
1899
1900 l_ptr->peer_session = msg_session(msg);
1901 l_ptr->peer_bearer_id = msg_bearer_id(msg);
1902
1903 if (msg_type(msg) == ACTIVATE_MSG)
1904 link_state_event(l_ptr, ACTIVATE_MSG);
1905 break;
1906 case STATE_MSG:
1907
1908 msg_tol = msg_link_tolerance(msg);
1909 if (msg_tol)
1910 link_set_supervision_props(l_ptr, msg_tol);
1911
1912 if (msg_linkprio(msg) &&
1913 (msg_linkprio(msg) != l_ptr->priority)) {
1914 pr_warn("%s<%s>, priority change %u->%u\n",
1915 link_rst_msg, l_ptr->name, l_ptr->priority,
1916 msg_linkprio(msg));
1917 l_ptr->priority = msg_linkprio(msg);
1918 tipc_link_reset(l_ptr); /* Enforce change to take effect */
1919 break;
1920 }
1921 link_state_event(l_ptr, TRAFFIC_MSG_EVT);
1922 l_ptr->stats.recv_states++;
1923 if (link_reset_unknown(l_ptr))
1924 break;
1925
1926 if (less_eq(mod(l_ptr->next_in_no), msg_next_sent(msg))) {
1927 rec_gap = mod(msg_next_sent(msg) -
1928 mod(l_ptr->next_in_no));
1929 }
1930
1931 max_pkt_ack = msg_max_pkt(msg);
1932 if (max_pkt_ack > l_ptr->max_pkt) {
1933 l_ptr->max_pkt = max_pkt_ack;
1934 l_ptr->max_pkt_probes = 0;
1935 }
1936
1937 max_pkt_ack = 0;
1938 if (msg_probe(msg)) {
1939 l_ptr->stats.recv_probes++;
1940 if (msg_size(msg) > sizeof(l_ptr->proto_msg))
1941 max_pkt_ack = msg_size(msg);
1942 }
1943
1944 /* Protocol message before retransmits, reduce loss risk */
1945 if (l_ptr->owner->bclink.recv_permitted)
1946 tipc_bclink_update_link_state(l_ptr->owner,
1947 msg_last_bcast(msg));
1948
1949 if (rec_gap || (msg_probe(msg))) {
1950 tipc_link_proto_xmit(l_ptr, STATE_MSG, 0, rec_gap, 0,
1951 0, max_pkt_ack);
1952 }
1953 if (msg_seq_gap(msg)) {
1954 l_ptr->stats.recv_nacks++;
1955 tipc_link_retransmit(l_ptr, l_ptr->first_out,
1956 msg_seq_gap(msg));
1957 }
1958 break;
1959 }
1960exit:
1961 kfree_skb(buf);
1962}
1963
1964
1965/* tipc_link_tunnel_xmit(): Tunnel one packet via a link belonging to
1966 * a different bearer. Owner node is locked.
1967 */
1968static void tipc_link_tunnel_xmit(struct tipc_link *l_ptr,
1969 struct tipc_msg *tunnel_hdr,
1970 struct tipc_msg *msg,
1971 u32 selector)
1972{
1973 struct tipc_link *tunnel;
1974 struct sk_buff *buf;
1975 u32 length = msg_size(msg);
1976
1977 tunnel = l_ptr->owner->active_links[selector & 1];
1978 if (!tipc_link_is_up(tunnel)) {
1979 pr_warn("%stunnel link no longer available\n", link_co_err);
1980 return;
1981 }
1982 msg_set_size(tunnel_hdr, length + INT_H_SIZE);
1983 buf = tipc_buf_acquire(length + INT_H_SIZE);
1984 if (!buf) {
1985 pr_warn("%sunable to send tunnel msg\n", link_co_err);
1986 return;
1987 }
1988 skb_copy_to_linear_data(buf, tunnel_hdr, INT_H_SIZE);
1989 skb_copy_to_linear_data_offset(buf, INT_H_SIZE, msg, length);
1990 __tipc_link_xmit(tunnel, buf);
1991}
1992
1993
1994/* tipc_link_failover_send_queue(): A link has gone down, but a second
1995 * link is still active. We can do failover. Tunnel the failing link's
1996 * whole send queue via the remaining link. This way, we don't lose
1997 * any packets, and sequence order is preserved for subsequent traffic
1998 * sent over the remaining link. Owner node is locked.
1999 */
2000void tipc_link_failover_send_queue(struct tipc_link *l_ptr)
2001{
2002 u32 msgcount = l_ptr->out_queue_size;
2003 struct sk_buff *crs = l_ptr->first_out;
2004 struct tipc_link *tunnel = l_ptr->owner->active_links[0];
2005 struct tipc_msg tunnel_hdr;
2006 int split_bundles;
2007
2008 if (!tunnel)
2009 return;
2010
2011 tipc_msg_init(&tunnel_hdr, CHANGEOVER_PROTOCOL,
2012 ORIGINAL_MSG, INT_H_SIZE, l_ptr->addr);
2013 msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id);
2014 msg_set_msgcnt(&tunnel_hdr, msgcount);
2015
2016 if (!l_ptr->first_out) {
2017 struct sk_buff *buf;
2018
2019 buf = tipc_buf_acquire(INT_H_SIZE);
2020 if (buf) {
2021 skb_copy_to_linear_data(buf, &tunnel_hdr, INT_H_SIZE);
2022 msg_set_size(&tunnel_hdr, INT_H_SIZE);
2023 __tipc_link_xmit(tunnel, buf);
2024 } else {
2025 pr_warn("%sunable to send changeover msg\n",
2026 link_co_err);
2027 }
2028 return;
2029 }
2030
2031 split_bundles = (l_ptr->owner->active_links[0] !=
2032 l_ptr->owner->active_links[1]);
2033
2034 while (crs) {
2035 struct tipc_msg *msg = buf_msg(crs);
2036
2037 if ((msg_user(msg) == MSG_BUNDLER) && split_bundles) {
2038 struct tipc_msg *m = msg_get_wrapped(msg);
2039 unchar *pos = (unchar *)m;
2040
2041 msgcount = msg_msgcnt(msg);
2042 while (msgcount--) {
2043 msg_set_seqno(m, msg_seqno(msg));
2044 tipc_link_tunnel_xmit(l_ptr, &tunnel_hdr, m,
2045 msg_link_selector(m));
2046 pos += align(msg_size(m));
2047 m = (struct tipc_msg *)pos;
2048 }
2049 } else {
2050 tipc_link_tunnel_xmit(l_ptr, &tunnel_hdr, msg,
2051 msg_link_selector(msg));
2052 }
2053 crs = crs->next;
2054 }
2055}
2056
2057/* tipc_link_dup_queue_xmit(): A second link has become active. Tunnel a
2058 * duplicate of the first link's send queue via the new link. This way, we
2059 * are guaranteed that currently queued packets from a socket are delivered
2060 * before future traffic from the same socket, even if this is using the
2061 * new link. The last arriving copy of each duplicate packet is dropped at
2062 * the receiving end by the regular protocol check, so packet cardinality
2063 * and sequence order is preserved per sender/receiver socket pair.
2064 * Owner node is locked.
2065 */
2066void tipc_link_dup_queue_xmit(struct tipc_link *l_ptr,
2067 struct tipc_link *tunnel)
2068{
2069 struct sk_buff *iter;
2070 struct tipc_msg tunnel_hdr;
2071
2072 tipc_msg_init(&tunnel_hdr, CHANGEOVER_PROTOCOL,
2073 DUPLICATE_MSG, INT_H_SIZE, l_ptr->addr);
2074 msg_set_msgcnt(&tunnel_hdr, l_ptr->out_queue_size);
2075 msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id);
2076 iter = l_ptr->first_out;
2077 while (iter) {
2078 struct sk_buff *outbuf;
2079 struct tipc_msg *msg = buf_msg(iter);
2080 u32 length = msg_size(msg);
2081
2082 if (msg_user(msg) == MSG_BUNDLER)
2083 msg_set_type(msg, CLOSED_MSG);
2084 msg_set_ack(msg, mod(l_ptr->next_in_no - 1)); /* Update */
2085 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
2086 msg_set_size(&tunnel_hdr, length + INT_H_SIZE);
2087 outbuf = tipc_buf_acquire(length + INT_H_SIZE);
2088 if (outbuf == NULL) {
2089 pr_warn("%sunable to send duplicate msg\n",
2090 link_co_err);
2091 return;
2092 }
2093 skb_copy_to_linear_data(outbuf, &tunnel_hdr, INT_H_SIZE);
2094 skb_copy_to_linear_data_offset(outbuf, INT_H_SIZE, iter->data,
2095 length);
2096 __tipc_link_xmit(tunnel, outbuf);
2097 if (!tipc_link_is_up(l_ptr))
2098 return;
2099 iter = iter->next;
2100 }
2101}
2102
2103/**
2104 * buf_extract - extracts embedded TIPC message from another message
2105 * @skb: encapsulating message buffer
2106 * @from_pos: offset to extract from
2107 *
2108 * Returns a new message buffer containing an embedded message. The
2109 * encapsulating message itself is left unchanged.
2110 */
2111static struct sk_buff *buf_extract(struct sk_buff *skb, u32 from_pos)
2112{
2113 struct tipc_msg *msg = (struct tipc_msg *)(skb->data + from_pos);
2114 u32 size = msg_size(msg);
2115 struct sk_buff *eb;
2116
2117 eb = tipc_buf_acquire(size);
2118 if (eb)
2119 skb_copy_to_linear_data(eb, msg, size);
2120 return eb;
2121}
2122
2123
2124
2125/* tipc_link_dup_rcv(): Receive a tunnelled DUPLICATE_MSG packet.
2126 * Owner node is locked.
2127 */
2128static void tipc_link_dup_rcv(struct tipc_link *l_ptr,
2129 struct sk_buff *t_buf)
2130{
2131 struct sk_buff *buf;
2132
2133 if (!tipc_link_is_up(l_ptr))
2134 return;
2135
2136 buf = buf_extract(t_buf, INT_H_SIZE);
2137 if (buf == NULL) {
2138 pr_warn("%sfailed to extract inner dup pkt\n", link_co_err);
2139 return;
2140 }
2141
2142 /* Add buffer to deferred queue, if applicable: */
2143 link_handle_out_of_seq_msg(l_ptr, buf);
2144}
2145
2146/* tipc_link_failover_rcv(): Receive a tunnelled ORIGINAL_MSG packet
2147 * Owner node is locked.
2148 */
2149static struct sk_buff *tipc_link_failover_rcv(struct tipc_link *l_ptr,
2150 struct sk_buff *t_buf)
2151{
2152 struct tipc_msg *t_msg = buf_msg(t_buf);
2153 struct sk_buff *buf = NULL;
2154 struct tipc_msg *msg;
2155
2156 if (tipc_link_is_up(l_ptr))
2157 tipc_link_reset(l_ptr);
2158
2159 /* First failover packet? */
2160 if (l_ptr->exp_msg_count == START_CHANGEOVER)
2161 l_ptr->exp_msg_count = msg_msgcnt(t_msg);
2162
2163 /* Should there be an inner packet? */
2164 if (l_ptr->exp_msg_count) {
2165 l_ptr->exp_msg_count--;
2166 buf = buf_extract(t_buf, INT_H_SIZE);
2167 if (buf == NULL) {
2168 pr_warn("%sno inner failover pkt\n", link_co_err);
2169 goto exit;
2170 }
2171 msg = buf_msg(buf);
2172
2173 if (less(msg_seqno(msg), l_ptr->reset_checkpoint)) {
2174 kfree_skb(buf);
2175 buf = NULL;
2176 goto exit;
2177 }
2178 if (msg_user(msg) == MSG_FRAGMENTER) {
2179 l_ptr->stats.recv_fragments++;
2180 tipc_link_frag_rcv(&l_ptr->reasm_head,
2181 &l_ptr->reasm_tail,
2182 &buf);
2183 }
2184 }
2185exit:
2186 if ((l_ptr->exp_msg_count == 0) && (l_ptr->flags & LINK_STOPPED)) {
2187 tipc_node_detach_link(l_ptr->owner, l_ptr);
2188 kfree(l_ptr);
2189 }
2190 return buf;
2191}
2192
2193/* tipc_link_tunnel_rcv(): Receive a tunnelled packet, sent
2194 * via other link as result of a failover (ORIGINAL_MSG) or
2195 * a new active link (DUPLICATE_MSG). Failover packets are
2196 * returned to the active link for delivery upwards.
2197 * Owner node is locked.
2198 */
2199static int tipc_link_tunnel_rcv(struct tipc_node *n_ptr,
2200 struct sk_buff **buf)
2201{
2202 struct sk_buff *t_buf = *buf;
2203 struct tipc_link *l_ptr;
2204 struct tipc_msg *t_msg = buf_msg(t_buf);
2205 u32 bearer_id = msg_bearer_id(t_msg);
2206
2207 *buf = NULL;
2208
2209 if (bearer_id >= MAX_BEARERS)
2210 goto exit;
2211
2212 l_ptr = n_ptr->links[bearer_id];
2213 if (!l_ptr)
2214 goto exit;
2215
2216 if (msg_type(t_msg) == DUPLICATE_MSG)
2217 tipc_link_dup_rcv(l_ptr, t_buf);
2218 else if (msg_type(t_msg) == ORIGINAL_MSG)
2219 *buf = tipc_link_failover_rcv(l_ptr, t_buf);
2220 else
2221 pr_warn("%sunknown tunnel pkt received\n", link_co_err);
2222exit:
2223 kfree_skb(t_buf);
2224 return *buf != NULL;
2225}
2226
2227/*
2228 * Bundler functionality:
2229 */
2230void tipc_link_bundle_rcv(struct sk_buff *buf)
2231{
2232 u32 msgcount = msg_msgcnt(buf_msg(buf));
2233 u32 pos = INT_H_SIZE;
2234 struct sk_buff *obuf;
2235
2236 while (msgcount--) {
2237 obuf = buf_extract(buf, pos);
2238 if (obuf == NULL) {
2239 pr_warn("Link unable to unbundle message(s)\n");
2240 break;
2241 }
2242 pos += align(msg_size(buf_msg(obuf)));
2243 tipc_net_route_msg(obuf);
2244 }
2245 kfree_skb(buf);
2246}
2247
2248/*
2249 * Fragmentation/defragmentation:
2250 */
2251
2252/*
2253 * tipc_link_frag_xmit: Entry for buffers needing fragmentation.
2254 * The buffer is complete, inclusive total message length.
2255 * Returns user data length.
2256 */
2257static int tipc_link_frag_xmit(struct tipc_link *l_ptr, struct sk_buff *buf)
2258{
2259 struct sk_buff *buf_chain = NULL;
2260 struct sk_buff *buf_chain_tail = (struct sk_buff *)&buf_chain;
2261 struct tipc_msg *inmsg = buf_msg(buf);
2262 struct tipc_msg fragm_hdr;
2263 u32 insize = msg_size(inmsg);
2264 u32 dsz = msg_data_sz(inmsg);
2265 unchar *crs = buf->data;
2266 u32 rest = insize;
2267 u32 pack_sz = l_ptr->max_pkt;
2268 u32 fragm_sz = pack_sz - INT_H_SIZE;
2269 u32 fragm_no = 0;
2270 u32 destaddr;
2271
2272 if (msg_short(inmsg))
2273 destaddr = l_ptr->addr;
2274 else
2275 destaddr = msg_destnode(inmsg);
2276
2277 /* Prepare reusable fragment header: */
2278 tipc_msg_init(&fragm_hdr, MSG_FRAGMENTER, FIRST_FRAGMENT,
2279 INT_H_SIZE, destaddr);
2280
2281 /* Chop up message: */
2282 while (rest > 0) {
2283 struct sk_buff *fragm;
2284
2285 if (rest <= fragm_sz) {
2286 fragm_sz = rest;
2287 msg_set_type(&fragm_hdr, LAST_FRAGMENT);
2288 }
2289 fragm = tipc_buf_acquire(fragm_sz + INT_H_SIZE);
2290 if (fragm == NULL) {
2291 kfree_skb(buf);
2292 kfree_skb_list(buf_chain);
2293 return -ENOMEM;
2294 }
2295 msg_set_size(&fragm_hdr, fragm_sz + INT_H_SIZE);
2296 fragm_no++;
2297 msg_set_fragm_no(&fragm_hdr, fragm_no);
2298 skb_copy_to_linear_data(fragm, &fragm_hdr, INT_H_SIZE);
2299 skb_copy_to_linear_data_offset(fragm, INT_H_SIZE, crs,
2300 fragm_sz);
2301 buf_chain_tail->next = fragm;
2302 buf_chain_tail = fragm;
2303
2304 rest -= fragm_sz;
2305 crs += fragm_sz;
2306 msg_set_type(&fragm_hdr, FRAGMENT);
2307 }
2308 kfree_skb(buf);
2309
2310 /* Append chain of fragments to send queue & send them */
2311 l_ptr->long_msg_seq_no++;
2312 link_add_chain_to_outqueue(l_ptr, buf_chain, l_ptr->long_msg_seq_no);
2313 l_ptr->stats.sent_fragments += fragm_no;
2314 l_ptr->stats.sent_fragmented++;
2315 tipc_link_push_queue(l_ptr);
2316
2317 return dsz;
2318}
2319
2320/* tipc_link_frag_rcv(): Called with node lock on. Returns
2321 * the reassembled buffer if message is complete.
2322 */
2323int tipc_link_frag_rcv(struct sk_buff **head, struct sk_buff **tail,
2324 struct sk_buff **fbuf)
2325{
2326 struct sk_buff *frag = *fbuf;
2327 struct tipc_msg *msg = buf_msg(frag);
2328 u32 fragid = msg_type(msg);
2329 bool headstolen;
2330 int delta;
2331
2332 skb_pull(frag, msg_hdr_sz(msg));
2333 if (fragid == FIRST_FRAGMENT) {
2334 if (*head || skb_unclone(frag, GFP_ATOMIC))
2335 goto out_free;
2336 *head = frag;
2337 skb_frag_list_init(*head);
2338 *fbuf = NULL;
2339 return 0;
2340 } else if (*head &&
2341 skb_try_coalesce(*head, frag, &headstolen, &delta)) {
2342 kfree_skb_partial(frag, headstolen);
2343 } else {
2344 if (!*head)
2345 goto out_free;
2346 if (!skb_has_frag_list(*head))
2347 skb_shinfo(*head)->frag_list = frag;
2348 else
2349 (*tail)->next = frag;
2350 *tail = frag;
2351 (*head)->truesize += frag->truesize;
2352 }
2353 if (fragid == LAST_FRAGMENT) {
2354 *fbuf = *head;
2355 *tail = *head = NULL;
2356 return LINK_REASM_COMPLETE;
2357 }
2358 *fbuf = NULL;
2359 return 0;
2360out_free:
2361 pr_warn_ratelimited("Link unable to reassemble fragmented message\n");
2362 kfree_skb(*fbuf);
2363 *fbuf = NULL;
2364 return LINK_REASM_ERROR;
2365}
2366
2367static void link_set_supervision_props(struct tipc_link *l_ptr, u32 tolerance)
2368{
2369 if ((tolerance < TIPC_MIN_LINK_TOL) || (tolerance > TIPC_MAX_LINK_TOL))
2370 return;
2371
2372 l_ptr->tolerance = tolerance;
2373 l_ptr->continuity_interval =
2374 ((tolerance / 4) > 500) ? 500 : tolerance / 4;
2375 l_ptr->abort_limit = tolerance / (l_ptr->continuity_interval / 4);
2376}
2377
2378void tipc_link_set_queue_limits(struct tipc_link *l_ptr, u32 window)
2379{
2380 /* Data messages from this node, inclusive FIRST_FRAGM */
2381 l_ptr->queue_limit[TIPC_LOW_IMPORTANCE] = window;
2382 l_ptr->queue_limit[TIPC_MEDIUM_IMPORTANCE] = (window / 3) * 4;
2383 l_ptr->queue_limit[TIPC_HIGH_IMPORTANCE] = (window / 3) * 5;
2384 l_ptr->queue_limit[TIPC_CRITICAL_IMPORTANCE] = (window / 3) * 6;
2385 /* Transiting data messages,inclusive FIRST_FRAGM */
2386 l_ptr->queue_limit[TIPC_LOW_IMPORTANCE + 4] = 300;
2387 l_ptr->queue_limit[TIPC_MEDIUM_IMPORTANCE + 4] = 600;
2388 l_ptr->queue_limit[TIPC_HIGH_IMPORTANCE + 4] = 900;
2389 l_ptr->queue_limit[TIPC_CRITICAL_IMPORTANCE + 4] = 1200;
2390 l_ptr->queue_limit[CONN_MANAGER] = 1200;
2391 l_ptr->queue_limit[CHANGEOVER_PROTOCOL] = 2500;
2392 l_ptr->queue_limit[NAME_DISTRIBUTOR] = 3000;
2393 /* FRAGMENT and LAST_FRAGMENT packets */
2394 l_ptr->queue_limit[MSG_FRAGMENTER] = 4000;
2395}
2396
2397/* tipc_link_find_owner - locate owner node of link by link's name
2398 * @name: pointer to link name string
2399 * @bearer_id: pointer to index in 'node->links' array where the link was found.
2400 * Caller must hold 'tipc_net_lock' to ensure node and bearer are not deleted;
2401 * this also prevents link deletion.
2402 *
2403 * Returns pointer to node owning the link, or 0 if no matching link is found.
2404 */
2405static struct tipc_node *tipc_link_find_owner(const char *link_name,
2406 unsigned int *bearer_id)
2407{
2408 struct tipc_link *l_ptr;
2409 struct tipc_node *n_ptr;
2410 struct tipc_node *found_node = 0;
2411 int i;
2412
2413 *bearer_id = 0;
2414 rcu_read_lock();
2415 list_for_each_entry_rcu(n_ptr, &tipc_node_list, list) {
2416 tipc_node_lock(n_ptr);
2417 for (i = 0; i < MAX_BEARERS; i++) {
2418 l_ptr = n_ptr->links[i];
2419 if (l_ptr && !strcmp(l_ptr->name, link_name)) {
2420 *bearer_id = i;
2421 found_node = n_ptr;
2422 break;
2423 }
2424 }
2425 tipc_node_unlock(n_ptr);
2426 if (found_node)
2427 break;
2428 }
2429 rcu_read_unlock();
2430
2431 return found_node;
2432}
2433
2434/**
2435 * link_value_is_valid -- validate proposed link tolerance/priority/window
2436 *
2437 * @cmd: value type (TIPC_CMD_SET_LINK_*)
2438 * @new_value: the new value
2439 *
2440 * Returns 1 if value is within range, 0 if not.
2441 */
2442static int link_value_is_valid(u16 cmd, u32 new_value)
2443{
2444 switch (cmd) {
2445 case TIPC_CMD_SET_LINK_TOL:
2446 return (new_value >= TIPC_MIN_LINK_TOL) &&
2447 (new_value <= TIPC_MAX_LINK_TOL);
2448 case TIPC_CMD_SET_LINK_PRI:
2449 return (new_value <= TIPC_MAX_LINK_PRI);
2450 case TIPC_CMD_SET_LINK_WINDOW:
2451 return (new_value >= TIPC_MIN_LINK_WIN) &&
2452 (new_value <= TIPC_MAX_LINK_WIN);
2453 }
2454 return 0;
2455}
2456
2457/**
2458 * link_cmd_set_value - change priority/tolerance/window for link/bearer/media
2459 * @name: ptr to link, bearer, or media name
2460 * @new_value: new value of link, bearer, or media setting
2461 * @cmd: which link, bearer, or media attribute to set (TIPC_CMD_SET_LINK_*)
2462 *
2463 * Caller must hold 'tipc_net_lock' to ensure link/bearer/media is not deleted.
2464 *
2465 * Returns 0 if value updated and negative value on error.
2466 */
2467static int link_cmd_set_value(const char *name, u32 new_value, u16 cmd)
2468{
2469 struct tipc_node *node;
2470 struct tipc_link *l_ptr;
2471 struct tipc_bearer *b_ptr;
2472 struct tipc_media *m_ptr;
2473 int bearer_id;
2474 int res = 0;
2475
2476 node = tipc_link_find_owner(name, &bearer_id);
2477 if (node) {
2478 tipc_node_lock(node);
2479 l_ptr = node->links[bearer_id];
2480
2481 if (l_ptr) {
2482 switch (cmd) {
2483 case TIPC_CMD_SET_LINK_TOL:
2484 link_set_supervision_props(l_ptr, new_value);
2485 tipc_link_proto_xmit(l_ptr, STATE_MSG, 0, 0,
2486 new_value, 0, 0);
2487 break;
2488 case TIPC_CMD_SET_LINK_PRI:
2489 l_ptr->priority = new_value;
2490 tipc_link_proto_xmit(l_ptr, STATE_MSG, 0, 0,
2491 0, new_value, 0);
2492 break;
2493 case TIPC_CMD_SET_LINK_WINDOW:
2494 tipc_link_set_queue_limits(l_ptr, new_value);
2495 break;
2496 default:
2497 res = -EINVAL;
2498 break;
2499 }
2500 }
2501 tipc_node_unlock(node);
2502 return res;
2503 }
2504
2505 b_ptr = tipc_bearer_find(name);
2506 if (b_ptr) {
2507 switch (cmd) {
2508 case TIPC_CMD_SET_LINK_TOL:
2509 b_ptr->tolerance = new_value;
2510 break;
2511 case TIPC_CMD_SET_LINK_PRI:
2512 b_ptr->priority = new_value;
2513 break;
2514 case TIPC_CMD_SET_LINK_WINDOW:
2515 b_ptr->window = new_value;
2516 break;
2517 default:
2518 res = -EINVAL;
2519 break;
2520 }
2521 return res;
2522 }
2523
2524 m_ptr = tipc_media_find(name);
2525 if (!m_ptr)
2526 return -ENODEV;
2527 switch (cmd) {
2528 case TIPC_CMD_SET_LINK_TOL:
2529 m_ptr->tolerance = new_value;
2530 break;
2531 case TIPC_CMD_SET_LINK_PRI:
2532 m_ptr->priority = new_value;
2533 break;
2534 case TIPC_CMD_SET_LINK_WINDOW:
2535 m_ptr->window = new_value;
2536 break;
2537 default:
2538 res = -EINVAL;
2539 break;
2540 }
2541 return res;
2542}
2543
2544struct sk_buff *tipc_link_cmd_config(const void *req_tlv_area, int req_tlv_space,
2545 u16 cmd)
2546{
2547 struct tipc_link_config *args;
2548 u32 new_value;
2549 int res;
2550
2551 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_CONFIG))
2552 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
2553
2554 args = (struct tipc_link_config *)TLV_DATA(req_tlv_area);
2555 new_value = ntohl(args->value);
2556
2557 if (!link_value_is_valid(cmd, new_value))
2558 return tipc_cfg_reply_error_string(
2559 "cannot change, value invalid");
2560
2561 if (!strcmp(args->name, tipc_bclink_name)) {
2562 if ((cmd == TIPC_CMD_SET_LINK_WINDOW) &&
2563 (tipc_bclink_set_queue_limits(new_value) == 0))
2564 return tipc_cfg_reply_none();
2565 return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED
2566 " (cannot change setting on broadcast link)");
2567 }
2568
2569 read_lock_bh(&tipc_net_lock);
2570 res = link_cmd_set_value(args->name, new_value, cmd);
2571 read_unlock_bh(&tipc_net_lock);
2572 if (res)
2573 return tipc_cfg_reply_error_string("cannot change link setting");
2574
2575 return tipc_cfg_reply_none();
2576}
2577
2578/**
2579 * link_reset_statistics - reset link statistics
2580 * @l_ptr: pointer to link
2581 */
2582static void link_reset_statistics(struct tipc_link *l_ptr)
2583{
2584 memset(&l_ptr->stats, 0, sizeof(l_ptr->stats));
2585 l_ptr->stats.sent_info = l_ptr->next_out_no;
2586 l_ptr->stats.recv_info = l_ptr->next_in_no;
2587}
2588
2589struct sk_buff *tipc_link_cmd_reset_stats(const void *req_tlv_area, int req_tlv_space)
2590{
2591 char *link_name;
2592 struct tipc_link *l_ptr;
2593 struct tipc_node *node;
2594 unsigned int bearer_id;
2595
2596 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_NAME))
2597 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
2598
2599 link_name = (char *)TLV_DATA(req_tlv_area);
2600 if (!strcmp(link_name, tipc_bclink_name)) {
2601 if (tipc_bclink_reset_stats())
2602 return tipc_cfg_reply_error_string("link not found");
2603 return tipc_cfg_reply_none();
2604 }
2605 read_lock_bh(&tipc_net_lock);
2606 node = tipc_link_find_owner(link_name, &bearer_id);
2607 if (!node) {
2608 read_unlock_bh(&tipc_net_lock);
2609 return tipc_cfg_reply_error_string("link not found");
2610 }
2611 tipc_node_lock(node);
2612 l_ptr = node->links[bearer_id];
2613 if (!l_ptr) {
2614 tipc_node_unlock(node);
2615 read_unlock_bh(&tipc_net_lock);
2616 return tipc_cfg_reply_error_string("link not found");
2617 }
2618 link_reset_statistics(l_ptr);
2619 tipc_node_unlock(node);
2620 read_unlock_bh(&tipc_net_lock);
2621 return tipc_cfg_reply_none();
2622}
2623
2624/**
2625 * percent - convert count to a percentage of total (rounding up or down)
2626 */
2627static u32 percent(u32 count, u32 total)
2628{
2629 return (count * 100 + (total / 2)) / total;
2630}
2631
2632/**
2633 * tipc_link_stats - print link statistics
2634 * @name: link name
2635 * @buf: print buffer area
2636 * @buf_size: size of print buffer area
2637 *
2638 * Returns length of print buffer data string (or 0 if error)
2639 */
2640static int tipc_link_stats(const char *name, char *buf, const u32 buf_size)
2641{
2642 struct tipc_link *l;
2643 struct tipc_stats *s;
2644 struct tipc_node *node;
2645 char *status;
2646 u32 profile_total = 0;
2647 unsigned int bearer_id;
2648 int ret;
2649
2650 if (!strcmp(name, tipc_bclink_name))
2651 return tipc_bclink_stats(buf, buf_size);
2652
2653 read_lock_bh(&tipc_net_lock);
2654 node = tipc_link_find_owner(name, &bearer_id);
2655 if (!node) {
2656 read_unlock_bh(&tipc_net_lock);
2657 return 0;
2658 }
2659 tipc_node_lock(node);
2660
2661 l = node->links[bearer_id];
2662 if (!l) {
2663 tipc_node_unlock(node);
2664 read_unlock_bh(&tipc_net_lock);
2665 return 0;
2666 }
2667
2668 s = &l->stats;
2669
2670 if (tipc_link_is_active(l))
2671 status = "ACTIVE";
2672 else if (tipc_link_is_up(l))
2673 status = "STANDBY";
2674 else
2675 status = "DEFUNCT";
2676
2677 ret = tipc_snprintf(buf, buf_size, "Link <%s>\n"
2678 " %s MTU:%u Priority:%u Tolerance:%u ms"
2679 " Window:%u packets\n",
2680 l->name, status, l->max_pkt, l->priority,
2681 l->tolerance, l->queue_limit[0]);
2682
2683 ret += tipc_snprintf(buf + ret, buf_size - ret,
2684 " RX packets:%u fragments:%u/%u bundles:%u/%u\n",
2685 l->next_in_no - s->recv_info, s->recv_fragments,
2686 s->recv_fragmented, s->recv_bundles,
2687 s->recv_bundled);
2688
2689 ret += tipc_snprintf(buf + ret, buf_size - ret,
2690 " TX packets:%u fragments:%u/%u bundles:%u/%u\n",
2691 l->next_out_no - s->sent_info, s->sent_fragments,
2692 s->sent_fragmented, s->sent_bundles,
2693 s->sent_bundled);
2694
2695 profile_total = s->msg_length_counts;
2696 if (!profile_total)
2697 profile_total = 1;
2698
2699 ret += tipc_snprintf(buf + ret, buf_size - ret,
2700 " TX profile sample:%u packets average:%u octets\n"
2701 " 0-64:%u%% -256:%u%% -1024:%u%% -4096:%u%% "
2702 "-16384:%u%% -32768:%u%% -66000:%u%%\n",
2703 s->msg_length_counts,
2704 s->msg_lengths_total / profile_total,
2705 percent(s->msg_length_profile[0], profile_total),
2706 percent(s->msg_length_profile[1], profile_total),
2707 percent(s->msg_length_profile[2], profile_total),
2708 percent(s->msg_length_profile[3], profile_total),
2709 percent(s->msg_length_profile[4], profile_total),
2710 percent(s->msg_length_profile[5], profile_total),
2711 percent(s->msg_length_profile[6], profile_total));
2712
2713 ret += tipc_snprintf(buf + ret, buf_size - ret,
2714 " RX states:%u probes:%u naks:%u defs:%u"
2715 " dups:%u\n", s->recv_states, s->recv_probes,
2716 s->recv_nacks, s->deferred_recv, s->duplicates);
2717
2718 ret += tipc_snprintf(buf + ret, buf_size - ret,
2719 " TX states:%u probes:%u naks:%u acks:%u"
2720 " dups:%u\n", s->sent_states, s->sent_probes,
2721 s->sent_nacks, s->sent_acks, s->retransmitted);
2722
2723 ret += tipc_snprintf(buf + ret, buf_size - ret,
2724 " Congestion link:%u Send queue"
2725 " max:%u avg:%u\n", s->link_congs,
2726 s->max_queue_sz, s->queue_sz_counts ?
2727 (s->accu_queue_sz / s->queue_sz_counts) : 0);
2728
2729 tipc_node_unlock(node);
2730 read_unlock_bh(&tipc_net_lock);
2731 return ret;
2732}
2733
2734struct sk_buff *tipc_link_cmd_show_stats(const void *req_tlv_area, int req_tlv_space)
2735{
2736 struct sk_buff *buf;
2737 struct tlv_desc *rep_tlv;
2738 int str_len;
2739 int pb_len;
2740 char *pb;
2741
2742 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_NAME))
2743 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
2744
2745 buf = tipc_cfg_reply_alloc(TLV_SPACE(ULTRA_STRING_MAX_LEN));
2746 if (!buf)
2747 return NULL;
2748
2749 rep_tlv = (struct tlv_desc *)buf->data;
2750 pb = TLV_DATA(rep_tlv);
2751 pb_len = ULTRA_STRING_MAX_LEN;
2752 str_len = tipc_link_stats((char *)TLV_DATA(req_tlv_area),
2753 pb, pb_len);
2754 if (!str_len) {
2755 kfree_skb(buf);
2756 return tipc_cfg_reply_error_string("link not found");
2757 }
2758 str_len += 1; /* for "\0" */
2759 skb_put(buf, TLV_SPACE(str_len));
2760 TLV_SET(rep_tlv, TIPC_TLV_ULTRA_STRING, NULL, str_len);
2761
2762 return buf;
2763}
2764
2765/**
2766 * tipc_link_get_max_pkt - get maximum packet size to use when sending to destination
2767 * @dest: network address of destination node
2768 * @selector: used to select from set of active links
2769 *
2770 * If no active link can be found, uses default maximum packet size.
2771 */
2772u32 tipc_link_get_max_pkt(u32 dest, u32 selector)
2773{
2774 struct tipc_node *n_ptr;
2775 struct tipc_link *l_ptr;
2776 u32 res = MAX_PKT_DEFAULT;
2777
2778 if (dest == tipc_own_addr)
2779 return MAX_MSG_SIZE;
2780
2781 read_lock_bh(&tipc_net_lock);
2782 n_ptr = tipc_node_find(dest);
2783 if (n_ptr) {
2784 tipc_node_lock(n_ptr);
2785 l_ptr = n_ptr->active_links[selector & 1];
2786 if (l_ptr)
2787 res = l_ptr->max_pkt;
2788 tipc_node_unlock(n_ptr);
2789 }
2790 read_unlock_bh(&tipc_net_lock);
2791 return res;
2792}
2793
2794static void link_print(struct tipc_link *l_ptr, const char *str)
2795{
2796 pr_info("%s Link %x<%s>:", str, l_ptr->addr, l_ptr->b_ptr->name);
2797
2798 if (link_working_unknown(l_ptr))
2799 pr_cont(":WU\n");
2800 else if (link_reset_reset(l_ptr))
2801 pr_cont(":RR\n");
2802 else if (link_reset_unknown(l_ptr))
2803 pr_cont(":RU\n");
2804 else if (link_working_working(l_ptr))
2805 pr_cont(":WW\n");
2806 else
2807 pr_cont("\n");
2808}
1/*
2 * net/tipc/link.c: TIPC link code
3 *
4 * Copyright (c) 1996-2007, Ericsson AB
5 * Copyright (c) 2004-2007, 2010-2011, Wind River Systems
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the names of the copyright holders nor the names of its
17 * contributors may be used to endorse or promote products derived from
18 * this software without specific prior written permission.
19 *
20 * Alternatively, this software may be distributed under the terms of the
21 * GNU General Public License ("GPL") version 2 as published by the Free
22 * Software Foundation.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34 * POSSIBILITY OF SUCH DAMAGE.
35 */
36
37#include "core.h"
38#include "link.h"
39#include "port.h"
40#include "name_distr.h"
41#include "discover.h"
42#include "config.h"
43
44
45/*
46 * Out-of-range value for link session numbers
47 */
48#define INVALID_SESSION 0x10000
49
50/*
51 * Link state events:
52 */
53#define STARTING_EVT 856384768 /* link processing trigger */
54#define TRAFFIC_MSG_EVT 560815u /* rx'd ??? */
55#define TIMEOUT_EVT 560817u /* link timer expired */
56
57/*
58 * The following two 'message types' is really just implementation
59 * data conveniently stored in the message header.
60 * They must not be considered part of the protocol
61 */
62#define OPEN_MSG 0
63#define CLOSED_MSG 1
64
65/*
66 * State value stored in 'exp_msg_count'
67 */
68#define START_CHANGEOVER 100000u
69
70/**
71 * struct tipc_link_name - deconstructed link name
72 * @addr_local: network address of node at this end
73 * @if_local: name of interface at this end
74 * @addr_peer: network address of node at far end
75 * @if_peer: name of interface at far end
76 */
77struct tipc_link_name {
78 u32 addr_local;
79 char if_local[TIPC_MAX_IF_NAME];
80 u32 addr_peer;
81 char if_peer[TIPC_MAX_IF_NAME];
82};
83
84static void link_handle_out_of_seq_msg(struct tipc_link *l_ptr,
85 struct sk_buff *buf);
86static void link_recv_proto_msg(struct tipc_link *l_ptr, struct sk_buff *buf);
87static int link_recv_changeover_msg(struct tipc_link **l_ptr,
88 struct sk_buff **buf);
89static void link_set_supervision_props(struct tipc_link *l_ptr, u32 tolerance);
90static int link_send_sections_long(struct tipc_port *sender,
91 struct iovec const *msg_sect,
92 u32 num_sect, unsigned int total_len,
93 u32 destnode);
94static void link_check_defragm_bufs(struct tipc_link *l_ptr);
95static void link_state_event(struct tipc_link *l_ptr, u32 event);
96static void link_reset_statistics(struct tipc_link *l_ptr);
97static void link_print(struct tipc_link *l_ptr, const char *str);
98static void link_start(struct tipc_link *l_ptr);
99static int link_send_long_buf(struct tipc_link *l_ptr, struct sk_buff *buf);
100
101/*
102 * Simple link routines
103 */
104static unsigned int align(unsigned int i)
105{
106 return (i + 3) & ~3u;
107}
108
109static void link_init_max_pkt(struct tipc_link *l_ptr)
110{
111 u32 max_pkt;
112
113 max_pkt = (l_ptr->b_ptr->mtu & ~3);
114 if (max_pkt > MAX_MSG_SIZE)
115 max_pkt = MAX_MSG_SIZE;
116
117 l_ptr->max_pkt_target = max_pkt;
118 if (l_ptr->max_pkt_target < MAX_PKT_DEFAULT)
119 l_ptr->max_pkt = l_ptr->max_pkt_target;
120 else
121 l_ptr->max_pkt = MAX_PKT_DEFAULT;
122
123 l_ptr->max_pkt_probes = 0;
124}
125
126static u32 link_next_sent(struct tipc_link *l_ptr)
127{
128 if (l_ptr->next_out)
129 return buf_seqno(l_ptr->next_out);
130 return mod(l_ptr->next_out_no);
131}
132
133static u32 link_last_sent(struct tipc_link *l_ptr)
134{
135 return mod(link_next_sent(l_ptr) - 1);
136}
137
138/*
139 * Simple non-static link routines (i.e. referenced outside this file)
140 */
141int tipc_link_is_up(struct tipc_link *l_ptr)
142{
143 if (!l_ptr)
144 return 0;
145 return link_working_working(l_ptr) || link_working_unknown(l_ptr);
146}
147
148int tipc_link_is_active(struct tipc_link *l_ptr)
149{
150 return (l_ptr->owner->active_links[0] == l_ptr) ||
151 (l_ptr->owner->active_links[1] == l_ptr);
152}
153
154/**
155 * link_name_validate - validate & (optionally) deconstruct tipc_link name
156 * @name - ptr to link name string
157 * @name_parts - ptr to area for link name components (or NULL if not needed)
158 *
159 * Returns 1 if link name is valid, otherwise 0.
160 */
161static int link_name_validate(const char *name,
162 struct tipc_link_name *name_parts)
163{
164 char name_copy[TIPC_MAX_LINK_NAME];
165 char *addr_local;
166 char *if_local;
167 char *addr_peer;
168 char *if_peer;
169 char dummy;
170 u32 z_local, c_local, n_local;
171 u32 z_peer, c_peer, n_peer;
172 u32 if_local_len;
173 u32 if_peer_len;
174
175 /* copy link name & ensure length is OK */
176 name_copy[TIPC_MAX_LINK_NAME - 1] = 0;
177 /* need above in case non-Posix strncpy() doesn't pad with nulls */
178 strncpy(name_copy, name, TIPC_MAX_LINK_NAME);
179 if (name_copy[TIPC_MAX_LINK_NAME - 1] != 0)
180 return 0;
181
182 /* ensure all component parts of link name are present */
183 addr_local = name_copy;
184 if_local = strchr(addr_local, ':');
185 if (if_local == NULL)
186 return 0;
187 *(if_local++) = 0;
188 addr_peer = strchr(if_local, '-');
189 if (addr_peer == NULL)
190 return 0;
191 *(addr_peer++) = 0;
192 if_local_len = addr_peer - if_local;
193 if_peer = strchr(addr_peer, ':');
194 if (if_peer == NULL)
195 return 0;
196 *(if_peer++) = 0;
197 if_peer_len = strlen(if_peer) + 1;
198
199 /* validate component parts of link name */
200 if ((sscanf(addr_local, "%u.%u.%u%c",
201 &z_local, &c_local, &n_local, &dummy) != 3) ||
202 (sscanf(addr_peer, "%u.%u.%u%c",
203 &z_peer, &c_peer, &n_peer, &dummy) != 3) ||
204 (z_local > 255) || (c_local > 4095) || (n_local > 4095) ||
205 (z_peer > 255) || (c_peer > 4095) || (n_peer > 4095) ||
206 (if_local_len <= 1) || (if_local_len > TIPC_MAX_IF_NAME) ||
207 (if_peer_len <= 1) || (if_peer_len > TIPC_MAX_IF_NAME) ||
208 (strspn(if_local, tipc_alphabet) != (if_local_len - 1)) ||
209 (strspn(if_peer, tipc_alphabet) != (if_peer_len - 1)))
210 return 0;
211
212 /* return link name components, if necessary */
213 if (name_parts) {
214 name_parts->addr_local = tipc_addr(z_local, c_local, n_local);
215 strcpy(name_parts->if_local, if_local);
216 name_parts->addr_peer = tipc_addr(z_peer, c_peer, n_peer);
217 strcpy(name_parts->if_peer, if_peer);
218 }
219 return 1;
220}
221
222/**
223 * link_timeout - handle expiration of link timer
224 * @l_ptr: pointer to link
225 *
226 * This routine must not grab "tipc_net_lock" to avoid a potential deadlock conflict
227 * with tipc_link_delete(). (There is no risk that the node will be deleted by
228 * another thread because tipc_link_delete() always cancels the link timer before
229 * tipc_node_delete() is called.)
230 */
231static void link_timeout(struct tipc_link *l_ptr)
232{
233 tipc_node_lock(l_ptr->owner);
234
235 /* update counters used in statistical profiling of send traffic */
236 l_ptr->stats.accu_queue_sz += l_ptr->out_queue_size;
237 l_ptr->stats.queue_sz_counts++;
238
239 if (l_ptr->first_out) {
240 struct tipc_msg *msg = buf_msg(l_ptr->first_out);
241 u32 length = msg_size(msg);
242
243 if ((msg_user(msg) == MSG_FRAGMENTER) &&
244 (msg_type(msg) == FIRST_FRAGMENT)) {
245 length = msg_size(msg_get_wrapped(msg));
246 }
247 if (length) {
248 l_ptr->stats.msg_lengths_total += length;
249 l_ptr->stats.msg_length_counts++;
250 if (length <= 64)
251 l_ptr->stats.msg_length_profile[0]++;
252 else if (length <= 256)
253 l_ptr->stats.msg_length_profile[1]++;
254 else if (length <= 1024)
255 l_ptr->stats.msg_length_profile[2]++;
256 else if (length <= 4096)
257 l_ptr->stats.msg_length_profile[3]++;
258 else if (length <= 16384)
259 l_ptr->stats.msg_length_profile[4]++;
260 else if (length <= 32768)
261 l_ptr->stats.msg_length_profile[5]++;
262 else
263 l_ptr->stats.msg_length_profile[6]++;
264 }
265 }
266
267 /* do all other link processing performed on a periodic basis */
268 link_check_defragm_bufs(l_ptr);
269
270 link_state_event(l_ptr, TIMEOUT_EVT);
271
272 if (l_ptr->next_out)
273 tipc_link_push_queue(l_ptr);
274
275 tipc_node_unlock(l_ptr->owner);
276}
277
278static void link_set_timer(struct tipc_link *l_ptr, u32 time)
279{
280 k_start_timer(&l_ptr->timer, time);
281}
282
283/**
284 * tipc_link_create - create a new link
285 * @n_ptr: pointer to associated node
286 * @b_ptr: pointer to associated bearer
287 * @media_addr: media address to use when sending messages over link
288 *
289 * Returns pointer to link.
290 */
291struct tipc_link *tipc_link_create(struct tipc_node *n_ptr,
292 struct tipc_bearer *b_ptr,
293 const struct tipc_media_addr *media_addr)
294{
295 struct tipc_link *l_ptr;
296 struct tipc_msg *msg;
297 char *if_name;
298 char addr_string[16];
299 u32 peer = n_ptr->addr;
300
301 if (n_ptr->link_cnt >= 2) {
302 tipc_addr_string_fill(addr_string, n_ptr->addr);
303 err("Attempt to establish third link to %s\n", addr_string);
304 return NULL;
305 }
306
307 if (n_ptr->links[b_ptr->identity]) {
308 tipc_addr_string_fill(addr_string, n_ptr->addr);
309 err("Attempt to establish second link on <%s> to %s\n",
310 b_ptr->name, addr_string);
311 return NULL;
312 }
313
314 l_ptr = kzalloc(sizeof(*l_ptr), GFP_ATOMIC);
315 if (!l_ptr) {
316 warn("Link creation failed, no memory\n");
317 return NULL;
318 }
319
320 l_ptr->addr = peer;
321 if_name = strchr(b_ptr->name, ':') + 1;
322 sprintf(l_ptr->name, "%u.%u.%u:%s-%u.%u.%u:unknown",
323 tipc_zone(tipc_own_addr), tipc_cluster(tipc_own_addr),
324 tipc_node(tipc_own_addr),
325 if_name,
326 tipc_zone(peer), tipc_cluster(peer), tipc_node(peer));
327 /* note: peer i/f name is updated by reset/activate message */
328 memcpy(&l_ptr->media_addr, media_addr, sizeof(*media_addr));
329 l_ptr->owner = n_ptr;
330 l_ptr->checkpoint = 1;
331 l_ptr->peer_session = INVALID_SESSION;
332 l_ptr->b_ptr = b_ptr;
333 link_set_supervision_props(l_ptr, b_ptr->tolerance);
334 l_ptr->state = RESET_UNKNOWN;
335
336 l_ptr->pmsg = (struct tipc_msg *)&l_ptr->proto_msg;
337 msg = l_ptr->pmsg;
338 tipc_msg_init(msg, LINK_PROTOCOL, RESET_MSG, INT_H_SIZE, l_ptr->addr);
339 msg_set_size(msg, sizeof(l_ptr->proto_msg));
340 msg_set_session(msg, (tipc_random & 0xffff));
341 msg_set_bearer_id(msg, b_ptr->identity);
342 strcpy((char *)msg_data(msg), if_name);
343
344 l_ptr->priority = b_ptr->priority;
345 tipc_link_set_queue_limits(l_ptr, b_ptr->window);
346
347 link_init_max_pkt(l_ptr);
348
349 l_ptr->next_out_no = 1;
350 INIT_LIST_HEAD(&l_ptr->waiting_ports);
351
352 link_reset_statistics(l_ptr);
353
354 tipc_node_attach_link(n_ptr, l_ptr);
355
356 k_init_timer(&l_ptr->timer, (Handler)link_timeout, (unsigned long)l_ptr);
357 list_add_tail(&l_ptr->link_list, &b_ptr->links);
358 tipc_k_signal((Handler)link_start, (unsigned long)l_ptr);
359
360 return l_ptr;
361}
362
363/**
364 * tipc_link_delete - delete a link
365 * @l_ptr: pointer to link
366 *
367 * Note: 'tipc_net_lock' is write_locked, bearer is locked.
368 * This routine must not grab the node lock until after link timer cancellation
369 * to avoid a potential deadlock situation.
370 */
371void tipc_link_delete(struct tipc_link *l_ptr)
372{
373 if (!l_ptr) {
374 err("Attempt to delete non-existent link\n");
375 return;
376 }
377
378 k_cancel_timer(&l_ptr->timer);
379
380 tipc_node_lock(l_ptr->owner);
381 tipc_link_reset(l_ptr);
382 tipc_node_detach_link(l_ptr->owner, l_ptr);
383 tipc_link_stop(l_ptr);
384 list_del_init(&l_ptr->link_list);
385 tipc_node_unlock(l_ptr->owner);
386 k_term_timer(&l_ptr->timer);
387 kfree(l_ptr);
388}
389
390static void link_start(struct tipc_link *l_ptr)
391{
392 tipc_node_lock(l_ptr->owner);
393 link_state_event(l_ptr, STARTING_EVT);
394 tipc_node_unlock(l_ptr->owner);
395}
396
397/**
398 * link_schedule_port - schedule port for deferred sending
399 * @l_ptr: pointer to link
400 * @origport: reference to sending port
401 * @sz: amount of data to be sent
402 *
403 * Schedules port for renewed sending of messages after link congestion
404 * has abated.
405 */
406static int link_schedule_port(struct tipc_link *l_ptr, u32 origport, u32 sz)
407{
408 struct tipc_port *p_ptr;
409
410 spin_lock_bh(&tipc_port_list_lock);
411 p_ptr = tipc_port_lock(origport);
412 if (p_ptr) {
413 if (!p_ptr->wakeup)
414 goto exit;
415 if (!list_empty(&p_ptr->wait_list))
416 goto exit;
417 p_ptr->congested = 1;
418 p_ptr->waiting_pkts = 1 + ((sz - 1) / l_ptr->max_pkt);
419 list_add_tail(&p_ptr->wait_list, &l_ptr->waiting_ports);
420 l_ptr->stats.link_congs++;
421exit:
422 tipc_port_unlock(p_ptr);
423 }
424 spin_unlock_bh(&tipc_port_list_lock);
425 return -ELINKCONG;
426}
427
428void tipc_link_wakeup_ports(struct tipc_link *l_ptr, int all)
429{
430 struct tipc_port *p_ptr;
431 struct tipc_port *temp_p_ptr;
432 int win = l_ptr->queue_limit[0] - l_ptr->out_queue_size;
433
434 if (all)
435 win = 100000;
436 if (win <= 0)
437 return;
438 if (!spin_trylock_bh(&tipc_port_list_lock))
439 return;
440 if (link_congested(l_ptr))
441 goto exit;
442 list_for_each_entry_safe(p_ptr, temp_p_ptr, &l_ptr->waiting_ports,
443 wait_list) {
444 if (win <= 0)
445 break;
446 list_del_init(&p_ptr->wait_list);
447 spin_lock_bh(p_ptr->lock);
448 p_ptr->congested = 0;
449 p_ptr->wakeup(p_ptr);
450 win -= p_ptr->waiting_pkts;
451 spin_unlock_bh(p_ptr->lock);
452 }
453
454exit:
455 spin_unlock_bh(&tipc_port_list_lock);
456}
457
458/**
459 * link_release_outqueue - purge link's outbound message queue
460 * @l_ptr: pointer to link
461 */
462static void link_release_outqueue(struct tipc_link *l_ptr)
463{
464 struct sk_buff *buf = l_ptr->first_out;
465 struct sk_buff *next;
466
467 while (buf) {
468 next = buf->next;
469 kfree_skb(buf);
470 buf = next;
471 }
472 l_ptr->first_out = NULL;
473 l_ptr->out_queue_size = 0;
474}
475
476/**
477 * tipc_link_reset_fragments - purge link's inbound message fragments queue
478 * @l_ptr: pointer to link
479 */
480void tipc_link_reset_fragments(struct tipc_link *l_ptr)
481{
482 struct sk_buff *buf = l_ptr->defragm_buf;
483 struct sk_buff *next;
484
485 while (buf) {
486 next = buf->next;
487 kfree_skb(buf);
488 buf = next;
489 }
490 l_ptr->defragm_buf = NULL;
491}
492
493/**
494 * tipc_link_stop - purge all inbound and outbound messages associated with link
495 * @l_ptr: pointer to link
496 */
497void tipc_link_stop(struct tipc_link *l_ptr)
498{
499 struct sk_buff *buf;
500 struct sk_buff *next;
501
502 buf = l_ptr->oldest_deferred_in;
503 while (buf) {
504 next = buf->next;
505 kfree_skb(buf);
506 buf = next;
507 }
508
509 buf = l_ptr->first_out;
510 while (buf) {
511 next = buf->next;
512 kfree_skb(buf);
513 buf = next;
514 }
515
516 tipc_link_reset_fragments(l_ptr);
517
518 kfree_skb(l_ptr->proto_msg_queue);
519 l_ptr->proto_msg_queue = NULL;
520}
521
522void tipc_link_reset(struct tipc_link *l_ptr)
523{
524 struct sk_buff *buf;
525 u32 prev_state = l_ptr->state;
526 u32 checkpoint = l_ptr->next_in_no;
527 int was_active_link = tipc_link_is_active(l_ptr);
528
529 msg_set_session(l_ptr->pmsg, ((msg_session(l_ptr->pmsg) + 1) & 0xffff));
530
531 /* Link is down, accept any session */
532 l_ptr->peer_session = INVALID_SESSION;
533
534 /* Prepare for max packet size negotiation */
535 link_init_max_pkt(l_ptr);
536
537 l_ptr->state = RESET_UNKNOWN;
538
539 if ((prev_state == RESET_UNKNOWN) || (prev_state == RESET_RESET))
540 return;
541
542 tipc_node_link_down(l_ptr->owner, l_ptr);
543 tipc_bearer_remove_dest(l_ptr->b_ptr, l_ptr->addr);
544
545 if (was_active_link && tipc_node_active_links(l_ptr->owner) &&
546 l_ptr->owner->permit_changeover) {
547 l_ptr->reset_checkpoint = checkpoint;
548 l_ptr->exp_msg_count = START_CHANGEOVER;
549 }
550
551 /* Clean up all queues: */
552 link_release_outqueue(l_ptr);
553 kfree_skb(l_ptr->proto_msg_queue);
554 l_ptr->proto_msg_queue = NULL;
555 buf = l_ptr->oldest_deferred_in;
556 while (buf) {
557 struct sk_buff *next = buf->next;
558 kfree_skb(buf);
559 buf = next;
560 }
561 if (!list_empty(&l_ptr->waiting_ports))
562 tipc_link_wakeup_ports(l_ptr, 1);
563
564 l_ptr->retransm_queue_head = 0;
565 l_ptr->retransm_queue_size = 0;
566 l_ptr->last_out = NULL;
567 l_ptr->first_out = NULL;
568 l_ptr->next_out = NULL;
569 l_ptr->unacked_window = 0;
570 l_ptr->checkpoint = 1;
571 l_ptr->next_out_no = 1;
572 l_ptr->deferred_inqueue_sz = 0;
573 l_ptr->oldest_deferred_in = NULL;
574 l_ptr->newest_deferred_in = NULL;
575 l_ptr->fsm_msg_cnt = 0;
576 l_ptr->stale_count = 0;
577 link_reset_statistics(l_ptr);
578}
579
580
581static void link_activate(struct tipc_link *l_ptr)
582{
583 l_ptr->next_in_no = l_ptr->stats.recv_info = 1;
584 tipc_node_link_up(l_ptr->owner, l_ptr);
585 tipc_bearer_add_dest(l_ptr->b_ptr, l_ptr->addr);
586}
587
588/**
589 * link_state_event - link finite state machine
590 * @l_ptr: pointer to link
591 * @event: state machine event to process
592 */
593static void link_state_event(struct tipc_link *l_ptr, unsigned int event)
594{
595 struct tipc_link *other;
596 u32 cont_intv = l_ptr->continuity_interval;
597
598 if (!l_ptr->started && (event != STARTING_EVT))
599 return; /* Not yet. */
600
601 if (link_blocked(l_ptr)) {
602 if (event == TIMEOUT_EVT)
603 link_set_timer(l_ptr, cont_intv);
604 return; /* Changeover going on */
605 }
606
607 switch (l_ptr->state) {
608 case WORKING_WORKING:
609 switch (event) {
610 case TRAFFIC_MSG_EVT:
611 case ACTIVATE_MSG:
612 break;
613 case TIMEOUT_EVT:
614 if (l_ptr->next_in_no != l_ptr->checkpoint) {
615 l_ptr->checkpoint = l_ptr->next_in_no;
616 if (tipc_bclink_acks_missing(l_ptr->owner)) {
617 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
618 0, 0, 0, 0, 0);
619 l_ptr->fsm_msg_cnt++;
620 } else if (l_ptr->max_pkt < l_ptr->max_pkt_target) {
621 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
622 1, 0, 0, 0, 0);
623 l_ptr->fsm_msg_cnt++;
624 }
625 link_set_timer(l_ptr, cont_intv);
626 break;
627 }
628 l_ptr->state = WORKING_UNKNOWN;
629 l_ptr->fsm_msg_cnt = 0;
630 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
631 l_ptr->fsm_msg_cnt++;
632 link_set_timer(l_ptr, cont_intv / 4);
633 break;
634 case RESET_MSG:
635 info("Resetting link <%s>, requested by peer\n",
636 l_ptr->name);
637 tipc_link_reset(l_ptr);
638 l_ptr->state = RESET_RESET;
639 l_ptr->fsm_msg_cnt = 0;
640 tipc_link_send_proto_msg(l_ptr, ACTIVATE_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 err("Unknown link event %u in WW state\n", event);
646 }
647 break;
648 case WORKING_UNKNOWN:
649 switch (event) {
650 case TRAFFIC_MSG_EVT:
651 case ACTIVATE_MSG:
652 l_ptr->state = WORKING_WORKING;
653 l_ptr->fsm_msg_cnt = 0;
654 link_set_timer(l_ptr, cont_intv);
655 break;
656 case RESET_MSG:
657 info("Resetting link <%s>, requested by peer "
658 "while probing\n", l_ptr->name);
659 tipc_link_reset(l_ptr);
660 l_ptr->state = RESET_RESET;
661 l_ptr->fsm_msg_cnt = 0;
662 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0);
663 l_ptr->fsm_msg_cnt++;
664 link_set_timer(l_ptr, cont_intv);
665 break;
666 case TIMEOUT_EVT:
667 if (l_ptr->next_in_no != l_ptr->checkpoint) {
668 l_ptr->state = WORKING_WORKING;
669 l_ptr->fsm_msg_cnt = 0;
670 l_ptr->checkpoint = l_ptr->next_in_no;
671 if (tipc_bclink_acks_missing(l_ptr->owner)) {
672 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
673 0, 0, 0, 0, 0);
674 l_ptr->fsm_msg_cnt++;
675 }
676 link_set_timer(l_ptr, cont_intv);
677 } else if (l_ptr->fsm_msg_cnt < l_ptr->abort_limit) {
678 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
679 1, 0, 0, 0, 0);
680 l_ptr->fsm_msg_cnt++;
681 link_set_timer(l_ptr, cont_intv / 4);
682 } else { /* Link has failed */
683 warn("Resetting link <%s>, peer not responding\n",
684 l_ptr->name);
685 tipc_link_reset(l_ptr);
686 l_ptr->state = RESET_UNKNOWN;
687 l_ptr->fsm_msg_cnt = 0;
688 tipc_link_send_proto_msg(l_ptr, RESET_MSG,
689 0, 0, 0, 0, 0);
690 l_ptr->fsm_msg_cnt++;
691 link_set_timer(l_ptr, cont_intv);
692 }
693 break;
694 default:
695 err("Unknown link event %u in WU state\n", event);
696 }
697 break;
698 case RESET_UNKNOWN:
699 switch (event) {
700 case TRAFFIC_MSG_EVT:
701 break;
702 case ACTIVATE_MSG:
703 other = l_ptr->owner->active_links[0];
704 if (other && link_working_unknown(other))
705 break;
706 l_ptr->state = WORKING_WORKING;
707 l_ptr->fsm_msg_cnt = 0;
708 link_activate(l_ptr);
709 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
710 l_ptr->fsm_msg_cnt++;
711 link_set_timer(l_ptr, cont_intv);
712 break;
713 case RESET_MSG:
714 l_ptr->state = RESET_RESET;
715 l_ptr->fsm_msg_cnt = 0;
716 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 1, 0, 0, 0, 0);
717 l_ptr->fsm_msg_cnt++;
718 link_set_timer(l_ptr, cont_intv);
719 break;
720 case STARTING_EVT:
721 l_ptr->started = 1;
722 /* fall through */
723 case TIMEOUT_EVT:
724 tipc_link_send_proto_msg(l_ptr, RESET_MSG, 0, 0, 0, 0, 0);
725 l_ptr->fsm_msg_cnt++;
726 link_set_timer(l_ptr, cont_intv);
727 break;
728 default:
729 err("Unknown link event %u in RU state\n", event);
730 }
731 break;
732 case RESET_RESET:
733 switch (event) {
734 case TRAFFIC_MSG_EVT:
735 case ACTIVATE_MSG:
736 other = l_ptr->owner->active_links[0];
737 if (other && link_working_unknown(other))
738 break;
739 l_ptr->state = WORKING_WORKING;
740 l_ptr->fsm_msg_cnt = 0;
741 link_activate(l_ptr);
742 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
743 l_ptr->fsm_msg_cnt++;
744 link_set_timer(l_ptr, cont_intv);
745 break;
746 case RESET_MSG:
747 break;
748 case TIMEOUT_EVT:
749 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0);
750 l_ptr->fsm_msg_cnt++;
751 link_set_timer(l_ptr, cont_intv);
752 break;
753 default:
754 err("Unknown link event %u in RR state\n", event);
755 }
756 break;
757 default:
758 err("Unknown link state %u/%u\n", l_ptr->state, event);
759 }
760}
761
762/*
763 * link_bundle_buf(): Append contents of a buffer to
764 * the tail of an existing one.
765 */
766static int link_bundle_buf(struct tipc_link *l_ptr,
767 struct sk_buff *bundler,
768 struct sk_buff *buf)
769{
770 struct tipc_msg *bundler_msg = buf_msg(bundler);
771 struct tipc_msg *msg = buf_msg(buf);
772 u32 size = msg_size(msg);
773 u32 bundle_size = msg_size(bundler_msg);
774 u32 to_pos = align(bundle_size);
775 u32 pad = to_pos - bundle_size;
776
777 if (msg_user(bundler_msg) != MSG_BUNDLER)
778 return 0;
779 if (msg_type(bundler_msg) != OPEN_MSG)
780 return 0;
781 if (skb_tailroom(bundler) < (pad + size))
782 return 0;
783 if (l_ptr->max_pkt < (to_pos + size))
784 return 0;
785
786 skb_put(bundler, pad + size);
787 skb_copy_to_linear_data_offset(bundler, to_pos, buf->data, size);
788 msg_set_size(bundler_msg, to_pos + size);
789 msg_set_msgcnt(bundler_msg, msg_msgcnt(bundler_msg) + 1);
790 kfree_skb(buf);
791 l_ptr->stats.sent_bundled++;
792 return 1;
793}
794
795static void link_add_to_outqueue(struct tipc_link *l_ptr,
796 struct sk_buff *buf,
797 struct tipc_msg *msg)
798{
799 u32 ack = mod(l_ptr->next_in_no - 1);
800 u32 seqno = mod(l_ptr->next_out_no++);
801
802 msg_set_word(msg, 2, ((ack << 16) | seqno));
803 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
804 buf->next = NULL;
805 if (l_ptr->first_out) {
806 l_ptr->last_out->next = buf;
807 l_ptr->last_out = buf;
808 } else
809 l_ptr->first_out = l_ptr->last_out = buf;
810
811 l_ptr->out_queue_size++;
812 if (l_ptr->out_queue_size > l_ptr->stats.max_queue_sz)
813 l_ptr->stats.max_queue_sz = l_ptr->out_queue_size;
814}
815
816static void link_add_chain_to_outqueue(struct tipc_link *l_ptr,
817 struct sk_buff *buf_chain,
818 u32 long_msgno)
819{
820 struct sk_buff *buf;
821 struct tipc_msg *msg;
822
823 if (!l_ptr->next_out)
824 l_ptr->next_out = buf_chain;
825 while (buf_chain) {
826 buf = buf_chain;
827 buf_chain = buf_chain->next;
828
829 msg = buf_msg(buf);
830 msg_set_long_msgno(msg, long_msgno);
831 link_add_to_outqueue(l_ptr, buf, msg);
832 }
833}
834
835/*
836 * tipc_link_send_buf() is the 'full path' for messages, called from
837 * inside TIPC when the 'fast path' in tipc_send_buf
838 * has failed, and from link_send()
839 */
840int tipc_link_send_buf(struct tipc_link *l_ptr, struct sk_buff *buf)
841{
842 struct tipc_msg *msg = buf_msg(buf);
843 u32 size = msg_size(msg);
844 u32 dsz = msg_data_sz(msg);
845 u32 queue_size = l_ptr->out_queue_size;
846 u32 imp = tipc_msg_tot_importance(msg);
847 u32 queue_limit = l_ptr->queue_limit[imp];
848 u32 max_packet = l_ptr->max_pkt;
849
850 /* Match msg importance against queue limits: */
851 if (unlikely(queue_size >= queue_limit)) {
852 if (imp <= TIPC_CRITICAL_IMPORTANCE) {
853 link_schedule_port(l_ptr, msg_origport(msg), size);
854 kfree_skb(buf);
855 return -ELINKCONG;
856 }
857 kfree_skb(buf);
858 if (imp > CONN_MANAGER) {
859 warn("Resetting link <%s>, send queue full", l_ptr->name);
860 tipc_link_reset(l_ptr);
861 }
862 return dsz;
863 }
864
865 /* Fragmentation needed ? */
866 if (size > max_packet)
867 return link_send_long_buf(l_ptr, buf);
868
869 /* Packet can be queued or sent. */
870 if (likely(!tipc_bearer_congested(l_ptr->b_ptr, l_ptr) &&
871 !link_congested(l_ptr))) {
872 link_add_to_outqueue(l_ptr, buf, msg);
873
874 if (likely(tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr))) {
875 l_ptr->unacked_window = 0;
876 } else {
877 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr);
878 l_ptr->stats.bearer_congs++;
879 l_ptr->next_out = buf;
880 }
881 return dsz;
882 }
883 /* Congestion: can message be bundled ? */
884 if ((msg_user(msg) != CHANGEOVER_PROTOCOL) &&
885 (msg_user(msg) != MSG_FRAGMENTER)) {
886
887 /* Try adding message to an existing bundle */
888 if (l_ptr->next_out &&
889 link_bundle_buf(l_ptr, l_ptr->last_out, buf)) {
890 tipc_bearer_resolve_congestion(l_ptr->b_ptr, l_ptr);
891 return dsz;
892 }
893
894 /* Try creating a new bundle */
895 if (size <= max_packet * 2 / 3) {
896 struct sk_buff *bundler = tipc_buf_acquire(max_packet);
897 struct tipc_msg bundler_hdr;
898
899 if (bundler) {
900 tipc_msg_init(&bundler_hdr, MSG_BUNDLER, OPEN_MSG,
901 INT_H_SIZE, l_ptr->addr);
902 skb_copy_to_linear_data(bundler, &bundler_hdr,
903 INT_H_SIZE);
904 skb_trim(bundler, INT_H_SIZE);
905 link_bundle_buf(l_ptr, bundler, buf);
906 buf = bundler;
907 msg = buf_msg(buf);
908 l_ptr->stats.sent_bundles++;
909 }
910 }
911 }
912 if (!l_ptr->next_out)
913 l_ptr->next_out = buf;
914 link_add_to_outqueue(l_ptr, buf, msg);
915 tipc_bearer_resolve_congestion(l_ptr->b_ptr, l_ptr);
916 return dsz;
917}
918
919/*
920 * tipc_link_send(): same as tipc_link_send_buf(), but the link to use has
921 * not been selected yet, and the the owner node is not locked
922 * Called by TIPC internal users, e.g. the name distributor
923 */
924int tipc_link_send(struct sk_buff *buf, u32 dest, u32 selector)
925{
926 struct tipc_link *l_ptr;
927 struct tipc_node *n_ptr;
928 int res = -ELINKCONG;
929
930 read_lock_bh(&tipc_net_lock);
931 n_ptr = tipc_node_find(dest);
932 if (n_ptr) {
933 tipc_node_lock(n_ptr);
934 l_ptr = n_ptr->active_links[selector & 1];
935 if (l_ptr)
936 res = tipc_link_send_buf(l_ptr, buf);
937 else
938 kfree_skb(buf);
939 tipc_node_unlock(n_ptr);
940 } else {
941 kfree_skb(buf);
942 }
943 read_unlock_bh(&tipc_net_lock);
944 return res;
945}
946
947/*
948 * tipc_link_send_names - send name table entries to new neighbor
949 *
950 * Send routine for bulk delivery of name table messages when contact
951 * with a new neighbor occurs. No link congestion checking is performed
952 * because name table messages *must* be delivered. The messages must be
953 * small enough not to require fragmentation.
954 * Called without any locks held.
955 */
956void tipc_link_send_names(struct list_head *message_list, u32 dest)
957{
958 struct tipc_node *n_ptr;
959 struct tipc_link *l_ptr;
960 struct sk_buff *buf;
961 struct sk_buff *temp_buf;
962
963 if (list_empty(message_list))
964 return;
965
966 read_lock_bh(&tipc_net_lock);
967 n_ptr = tipc_node_find(dest);
968 if (n_ptr) {
969 tipc_node_lock(n_ptr);
970 l_ptr = n_ptr->active_links[0];
971 if (l_ptr) {
972 /* convert circular list to linear list */
973 ((struct sk_buff *)message_list->prev)->next = NULL;
974 link_add_chain_to_outqueue(l_ptr,
975 (struct sk_buff *)message_list->next, 0);
976 tipc_link_push_queue(l_ptr);
977 INIT_LIST_HEAD(message_list);
978 }
979 tipc_node_unlock(n_ptr);
980 }
981 read_unlock_bh(&tipc_net_lock);
982
983 /* discard the messages if they couldn't be sent */
984 list_for_each_safe(buf, temp_buf, ((struct sk_buff *)message_list)) {
985 list_del((struct list_head *)buf);
986 kfree_skb(buf);
987 }
988}
989
990/*
991 * link_send_buf_fast: Entry for data messages where the
992 * destination link is known and the header is complete,
993 * inclusive total message length. Very time critical.
994 * Link is locked. Returns user data length.
995 */
996static int link_send_buf_fast(struct tipc_link *l_ptr, struct sk_buff *buf,
997 u32 *used_max_pkt)
998{
999 struct tipc_msg *msg = buf_msg(buf);
1000 int res = msg_data_sz(msg);
1001
1002 if (likely(!link_congested(l_ptr))) {
1003 if (likely(msg_size(msg) <= l_ptr->max_pkt)) {
1004 if (likely(list_empty(&l_ptr->b_ptr->cong_links))) {
1005 link_add_to_outqueue(l_ptr, buf, msg);
1006 if (likely(tipc_bearer_send(l_ptr->b_ptr, buf,
1007 &l_ptr->media_addr))) {
1008 l_ptr->unacked_window = 0;
1009 return res;
1010 }
1011 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr);
1012 l_ptr->stats.bearer_congs++;
1013 l_ptr->next_out = buf;
1014 return res;
1015 }
1016 } else
1017 *used_max_pkt = l_ptr->max_pkt;
1018 }
1019 return tipc_link_send_buf(l_ptr, buf); /* All other cases */
1020}
1021
1022/*
1023 * tipc_send_buf_fast: Entry for data messages where the
1024 * destination node is known and the header is complete,
1025 * inclusive total message length.
1026 * Returns user data length.
1027 */
1028int tipc_send_buf_fast(struct sk_buff *buf, u32 destnode)
1029{
1030 struct tipc_link *l_ptr;
1031 struct tipc_node *n_ptr;
1032 int res;
1033 u32 selector = msg_origport(buf_msg(buf)) & 1;
1034 u32 dummy;
1035
1036 read_lock_bh(&tipc_net_lock);
1037 n_ptr = tipc_node_find(destnode);
1038 if (likely(n_ptr)) {
1039 tipc_node_lock(n_ptr);
1040 l_ptr = n_ptr->active_links[selector];
1041 if (likely(l_ptr)) {
1042 res = link_send_buf_fast(l_ptr, buf, &dummy);
1043 tipc_node_unlock(n_ptr);
1044 read_unlock_bh(&tipc_net_lock);
1045 return res;
1046 }
1047 tipc_node_unlock(n_ptr);
1048 }
1049 read_unlock_bh(&tipc_net_lock);
1050 res = msg_data_sz(buf_msg(buf));
1051 tipc_reject_msg(buf, TIPC_ERR_NO_NODE);
1052 return res;
1053}
1054
1055
1056/*
1057 * tipc_link_send_sections_fast: Entry for messages where the
1058 * destination processor is known and the header is complete,
1059 * except for total message length.
1060 * Returns user data length or errno.
1061 */
1062int tipc_link_send_sections_fast(struct tipc_port *sender,
1063 struct iovec const *msg_sect,
1064 const u32 num_sect,
1065 unsigned int total_len,
1066 u32 destaddr)
1067{
1068 struct tipc_msg *hdr = &sender->phdr;
1069 struct tipc_link *l_ptr;
1070 struct sk_buff *buf;
1071 struct tipc_node *node;
1072 int res;
1073 u32 selector = msg_origport(hdr) & 1;
1074
1075again:
1076 /*
1077 * Try building message using port's max_pkt hint.
1078 * (Must not hold any locks while building message.)
1079 */
1080 res = tipc_msg_build(hdr, msg_sect, num_sect, total_len,
1081 sender->max_pkt, !sender->user_port, &buf);
1082
1083 read_lock_bh(&tipc_net_lock);
1084 node = tipc_node_find(destaddr);
1085 if (likely(node)) {
1086 tipc_node_lock(node);
1087 l_ptr = node->active_links[selector];
1088 if (likely(l_ptr)) {
1089 if (likely(buf)) {
1090 res = link_send_buf_fast(l_ptr, buf,
1091 &sender->max_pkt);
1092exit:
1093 tipc_node_unlock(node);
1094 read_unlock_bh(&tipc_net_lock);
1095 return res;
1096 }
1097
1098 /* Exit if build request was invalid */
1099 if (unlikely(res < 0))
1100 goto exit;
1101
1102 /* Exit if link (or bearer) is congested */
1103 if (link_congested(l_ptr) ||
1104 !list_empty(&l_ptr->b_ptr->cong_links)) {
1105 res = link_schedule_port(l_ptr,
1106 sender->ref, res);
1107 goto exit;
1108 }
1109
1110 /*
1111 * Message size exceeds max_pkt hint; update hint,
1112 * then re-try fast path or fragment the message
1113 */
1114 sender->max_pkt = l_ptr->max_pkt;
1115 tipc_node_unlock(node);
1116 read_unlock_bh(&tipc_net_lock);
1117
1118
1119 if ((msg_hdr_sz(hdr) + res) <= sender->max_pkt)
1120 goto again;
1121
1122 return link_send_sections_long(sender, msg_sect,
1123 num_sect, total_len,
1124 destaddr);
1125 }
1126 tipc_node_unlock(node);
1127 }
1128 read_unlock_bh(&tipc_net_lock);
1129
1130 /* Couldn't find a link to the destination node */
1131 if (buf)
1132 return tipc_reject_msg(buf, TIPC_ERR_NO_NODE);
1133 if (res >= 0)
1134 return tipc_port_reject_sections(sender, hdr, msg_sect, num_sect,
1135 total_len, TIPC_ERR_NO_NODE);
1136 return res;
1137}
1138
1139/*
1140 * link_send_sections_long(): Entry for long messages where the
1141 * destination node is known and the header is complete,
1142 * inclusive total message length.
1143 * Link and bearer congestion status have been checked to be ok,
1144 * and are ignored if they change.
1145 *
1146 * Note that fragments do not use the full link MTU so that they won't have
1147 * to undergo refragmentation if link changeover causes them to be sent
1148 * over another link with an additional tunnel header added as prefix.
1149 * (Refragmentation will still occur if the other link has a smaller MTU.)
1150 *
1151 * Returns user data length or errno.
1152 */
1153static int link_send_sections_long(struct tipc_port *sender,
1154 struct iovec const *msg_sect,
1155 u32 num_sect,
1156 unsigned int total_len,
1157 u32 destaddr)
1158{
1159 struct tipc_link *l_ptr;
1160 struct tipc_node *node;
1161 struct tipc_msg *hdr = &sender->phdr;
1162 u32 dsz = total_len;
1163 u32 max_pkt, fragm_sz, rest;
1164 struct tipc_msg fragm_hdr;
1165 struct sk_buff *buf, *buf_chain, *prev;
1166 u32 fragm_crs, fragm_rest, hsz, sect_rest;
1167 const unchar *sect_crs;
1168 int curr_sect;
1169 u32 fragm_no;
1170
1171again:
1172 fragm_no = 1;
1173 max_pkt = sender->max_pkt - INT_H_SIZE;
1174 /* leave room for tunnel header in case of link changeover */
1175 fragm_sz = max_pkt - INT_H_SIZE;
1176 /* leave room for fragmentation header in each fragment */
1177 rest = dsz;
1178 fragm_crs = 0;
1179 fragm_rest = 0;
1180 sect_rest = 0;
1181 sect_crs = NULL;
1182 curr_sect = -1;
1183
1184 /* Prepare reusable fragment header */
1185 tipc_msg_init(&fragm_hdr, MSG_FRAGMENTER, FIRST_FRAGMENT,
1186 INT_H_SIZE, msg_destnode(hdr));
1187 msg_set_size(&fragm_hdr, max_pkt);
1188 msg_set_fragm_no(&fragm_hdr, 1);
1189
1190 /* Prepare header of first fragment */
1191 buf_chain = buf = tipc_buf_acquire(max_pkt);
1192 if (!buf)
1193 return -ENOMEM;
1194 buf->next = NULL;
1195 skb_copy_to_linear_data(buf, &fragm_hdr, INT_H_SIZE);
1196 hsz = msg_hdr_sz(hdr);
1197 skb_copy_to_linear_data_offset(buf, INT_H_SIZE, hdr, hsz);
1198
1199 /* Chop up message */
1200 fragm_crs = INT_H_SIZE + hsz;
1201 fragm_rest = fragm_sz - hsz;
1202
1203 do { /* For all sections */
1204 u32 sz;
1205
1206 if (!sect_rest) {
1207 sect_rest = msg_sect[++curr_sect].iov_len;
1208 sect_crs = (const unchar *)msg_sect[curr_sect].iov_base;
1209 }
1210
1211 if (sect_rest < fragm_rest)
1212 sz = sect_rest;
1213 else
1214 sz = fragm_rest;
1215
1216 if (likely(!sender->user_port)) {
1217 if (copy_from_user(buf->data + fragm_crs, sect_crs, sz)) {
1218error:
1219 for (; buf_chain; buf_chain = buf) {
1220 buf = buf_chain->next;
1221 kfree_skb(buf_chain);
1222 }
1223 return -EFAULT;
1224 }
1225 } else
1226 skb_copy_to_linear_data_offset(buf, fragm_crs,
1227 sect_crs, sz);
1228 sect_crs += sz;
1229 sect_rest -= sz;
1230 fragm_crs += sz;
1231 fragm_rest -= sz;
1232 rest -= sz;
1233
1234 if (!fragm_rest && rest) {
1235
1236 /* Initiate new fragment: */
1237 if (rest <= fragm_sz) {
1238 fragm_sz = rest;
1239 msg_set_type(&fragm_hdr, LAST_FRAGMENT);
1240 } else {
1241 msg_set_type(&fragm_hdr, FRAGMENT);
1242 }
1243 msg_set_size(&fragm_hdr, fragm_sz + INT_H_SIZE);
1244 msg_set_fragm_no(&fragm_hdr, ++fragm_no);
1245 prev = buf;
1246 buf = tipc_buf_acquire(fragm_sz + INT_H_SIZE);
1247 if (!buf)
1248 goto error;
1249
1250 buf->next = NULL;
1251 prev->next = buf;
1252 skb_copy_to_linear_data(buf, &fragm_hdr, INT_H_SIZE);
1253 fragm_crs = INT_H_SIZE;
1254 fragm_rest = fragm_sz;
1255 }
1256 } while (rest > 0);
1257
1258 /*
1259 * Now we have a buffer chain. Select a link and check
1260 * that packet size is still OK
1261 */
1262 node = tipc_node_find(destaddr);
1263 if (likely(node)) {
1264 tipc_node_lock(node);
1265 l_ptr = node->active_links[sender->ref & 1];
1266 if (!l_ptr) {
1267 tipc_node_unlock(node);
1268 goto reject;
1269 }
1270 if (l_ptr->max_pkt < max_pkt) {
1271 sender->max_pkt = l_ptr->max_pkt;
1272 tipc_node_unlock(node);
1273 for (; buf_chain; buf_chain = buf) {
1274 buf = buf_chain->next;
1275 kfree_skb(buf_chain);
1276 }
1277 goto again;
1278 }
1279 } else {
1280reject:
1281 for (; buf_chain; buf_chain = buf) {
1282 buf = buf_chain->next;
1283 kfree_skb(buf_chain);
1284 }
1285 return tipc_port_reject_sections(sender, hdr, msg_sect, num_sect,
1286 total_len, TIPC_ERR_NO_NODE);
1287 }
1288
1289 /* Append chain of fragments to send queue & send them */
1290 l_ptr->long_msg_seq_no++;
1291 link_add_chain_to_outqueue(l_ptr, buf_chain, l_ptr->long_msg_seq_no);
1292 l_ptr->stats.sent_fragments += fragm_no;
1293 l_ptr->stats.sent_fragmented++;
1294 tipc_link_push_queue(l_ptr);
1295 tipc_node_unlock(node);
1296 return dsz;
1297}
1298
1299/*
1300 * tipc_link_push_packet: Push one unsent packet to the media
1301 */
1302u32 tipc_link_push_packet(struct tipc_link *l_ptr)
1303{
1304 struct sk_buff *buf = l_ptr->first_out;
1305 u32 r_q_size = l_ptr->retransm_queue_size;
1306 u32 r_q_head = l_ptr->retransm_queue_head;
1307
1308 /* Step to position where retransmission failed, if any, */
1309 /* consider that buffers may have been released in meantime */
1310 if (r_q_size && buf) {
1311 u32 last = lesser(mod(r_q_head + r_q_size),
1312 link_last_sent(l_ptr));
1313 u32 first = buf_seqno(buf);
1314
1315 while (buf && less(first, r_q_head)) {
1316 first = mod(first + 1);
1317 buf = buf->next;
1318 }
1319 l_ptr->retransm_queue_head = r_q_head = first;
1320 l_ptr->retransm_queue_size = r_q_size = mod(last - first);
1321 }
1322
1323 /* Continue retransmission now, if there is anything: */
1324 if (r_q_size && buf) {
1325 msg_set_ack(buf_msg(buf), mod(l_ptr->next_in_no - 1));
1326 msg_set_bcast_ack(buf_msg(buf), l_ptr->owner->bclink.last_in);
1327 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) {
1328 l_ptr->retransm_queue_head = mod(++r_q_head);
1329 l_ptr->retransm_queue_size = --r_q_size;
1330 l_ptr->stats.retransmitted++;
1331 return 0;
1332 } else {
1333 l_ptr->stats.bearer_congs++;
1334 return PUSH_FAILED;
1335 }
1336 }
1337
1338 /* Send deferred protocol message, if any: */
1339 buf = l_ptr->proto_msg_queue;
1340 if (buf) {
1341 msg_set_ack(buf_msg(buf), mod(l_ptr->next_in_no - 1));
1342 msg_set_bcast_ack(buf_msg(buf), l_ptr->owner->bclink.last_in);
1343 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) {
1344 l_ptr->unacked_window = 0;
1345 kfree_skb(buf);
1346 l_ptr->proto_msg_queue = NULL;
1347 return 0;
1348 } else {
1349 l_ptr->stats.bearer_congs++;
1350 return PUSH_FAILED;
1351 }
1352 }
1353
1354 /* Send one deferred data message, if send window not full: */
1355 buf = l_ptr->next_out;
1356 if (buf) {
1357 struct tipc_msg *msg = buf_msg(buf);
1358 u32 next = msg_seqno(msg);
1359 u32 first = buf_seqno(l_ptr->first_out);
1360
1361 if (mod(next - first) < l_ptr->queue_limit[0]) {
1362 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
1363 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1364 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) {
1365 if (msg_user(msg) == MSG_BUNDLER)
1366 msg_set_type(msg, CLOSED_MSG);
1367 l_ptr->next_out = buf->next;
1368 return 0;
1369 } else {
1370 l_ptr->stats.bearer_congs++;
1371 return PUSH_FAILED;
1372 }
1373 }
1374 }
1375 return PUSH_FINISHED;
1376}
1377
1378/*
1379 * push_queue(): push out the unsent messages of a link where
1380 * congestion has abated. Node is locked
1381 */
1382void tipc_link_push_queue(struct tipc_link *l_ptr)
1383{
1384 u32 res;
1385
1386 if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr))
1387 return;
1388
1389 do {
1390 res = tipc_link_push_packet(l_ptr);
1391 } while (!res);
1392
1393 if (res == PUSH_FAILED)
1394 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr);
1395}
1396
1397static void link_reset_all(unsigned long addr)
1398{
1399 struct tipc_node *n_ptr;
1400 char addr_string[16];
1401 u32 i;
1402
1403 read_lock_bh(&tipc_net_lock);
1404 n_ptr = tipc_node_find((u32)addr);
1405 if (!n_ptr) {
1406 read_unlock_bh(&tipc_net_lock);
1407 return; /* node no longer exists */
1408 }
1409
1410 tipc_node_lock(n_ptr);
1411
1412 warn("Resetting all links to %s\n",
1413 tipc_addr_string_fill(addr_string, n_ptr->addr));
1414
1415 for (i = 0; i < MAX_BEARERS; i++) {
1416 if (n_ptr->links[i]) {
1417 link_print(n_ptr->links[i], "Resetting link\n");
1418 tipc_link_reset(n_ptr->links[i]);
1419 }
1420 }
1421
1422 tipc_node_unlock(n_ptr);
1423 read_unlock_bh(&tipc_net_lock);
1424}
1425
1426static void link_retransmit_failure(struct tipc_link *l_ptr,
1427 struct sk_buff *buf)
1428{
1429 struct tipc_msg *msg = buf_msg(buf);
1430
1431 warn("Retransmission failure on link <%s>\n", l_ptr->name);
1432
1433 if (l_ptr->addr) {
1434 /* Handle failure on standard link */
1435 link_print(l_ptr, "Resetting link\n");
1436 tipc_link_reset(l_ptr);
1437
1438 } else {
1439 /* Handle failure on broadcast link */
1440 struct tipc_node *n_ptr;
1441 char addr_string[16];
1442
1443 info("Msg seq number: %u, ", msg_seqno(msg));
1444 info("Outstanding acks: %lu\n",
1445 (unsigned long) TIPC_SKB_CB(buf)->handle);
1446
1447 n_ptr = tipc_bclink_retransmit_to();
1448 tipc_node_lock(n_ptr);
1449
1450 tipc_addr_string_fill(addr_string, n_ptr->addr);
1451 info("Broadcast link info for %s\n", addr_string);
1452 info("Supportable: %d, ", n_ptr->bclink.supportable);
1453 info("Supported: %d, ", n_ptr->bclink.supported);
1454 info("Acked: %u\n", n_ptr->bclink.acked);
1455 info("Last in: %u, ", n_ptr->bclink.last_in);
1456 info("Oos state: %u, ", n_ptr->bclink.oos_state);
1457 info("Last sent: %u\n", n_ptr->bclink.last_sent);
1458
1459 tipc_k_signal((Handler)link_reset_all, (unsigned long)n_ptr->addr);
1460
1461 tipc_node_unlock(n_ptr);
1462
1463 l_ptr->stale_count = 0;
1464 }
1465}
1466
1467void tipc_link_retransmit(struct tipc_link *l_ptr, struct sk_buff *buf,
1468 u32 retransmits)
1469{
1470 struct tipc_msg *msg;
1471
1472 if (!buf)
1473 return;
1474
1475 msg = buf_msg(buf);
1476
1477 if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr)) {
1478 if (l_ptr->retransm_queue_size == 0) {
1479 l_ptr->retransm_queue_head = msg_seqno(msg);
1480 l_ptr->retransm_queue_size = retransmits;
1481 } else {
1482 err("Unexpected retransmit on link %s (qsize=%d)\n",
1483 l_ptr->name, l_ptr->retransm_queue_size);
1484 }
1485 return;
1486 } else {
1487 /* Detect repeated retransmit failures on uncongested bearer */
1488 if (l_ptr->last_retransmitted == msg_seqno(msg)) {
1489 if (++l_ptr->stale_count > 100) {
1490 link_retransmit_failure(l_ptr, buf);
1491 return;
1492 }
1493 } else {
1494 l_ptr->last_retransmitted = msg_seqno(msg);
1495 l_ptr->stale_count = 1;
1496 }
1497 }
1498
1499 while (retransmits && (buf != l_ptr->next_out) && buf) {
1500 msg = buf_msg(buf);
1501 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
1502 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1503 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) {
1504 buf = buf->next;
1505 retransmits--;
1506 l_ptr->stats.retransmitted++;
1507 } else {
1508 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr);
1509 l_ptr->stats.bearer_congs++;
1510 l_ptr->retransm_queue_head = buf_seqno(buf);
1511 l_ptr->retransm_queue_size = retransmits;
1512 return;
1513 }
1514 }
1515
1516 l_ptr->retransm_queue_head = l_ptr->retransm_queue_size = 0;
1517}
1518
1519/**
1520 * link_insert_deferred_queue - insert deferred messages back into receive chain
1521 */
1522static struct sk_buff *link_insert_deferred_queue(struct tipc_link *l_ptr,
1523 struct sk_buff *buf)
1524{
1525 u32 seq_no;
1526
1527 if (l_ptr->oldest_deferred_in == NULL)
1528 return buf;
1529
1530 seq_no = buf_seqno(l_ptr->oldest_deferred_in);
1531 if (seq_no == mod(l_ptr->next_in_no)) {
1532 l_ptr->newest_deferred_in->next = buf;
1533 buf = l_ptr->oldest_deferred_in;
1534 l_ptr->oldest_deferred_in = NULL;
1535 l_ptr->deferred_inqueue_sz = 0;
1536 }
1537 return buf;
1538}
1539
1540/**
1541 * link_recv_buf_validate - validate basic format of received message
1542 *
1543 * This routine ensures a TIPC message has an acceptable header, and at least
1544 * as much data as the header indicates it should. The routine also ensures
1545 * that the entire message header is stored in the main fragment of the message
1546 * buffer, to simplify future access to message header fields.
1547 *
1548 * Note: Having extra info present in the message header or data areas is OK.
1549 * TIPC will ignore the excess, under the assumption that it is optional info
1550 * introduced by a later release of the protocol.
1551 */
1552static int link_recv_buf_validate(struct sk_buff *buf)
1553{
1554 static u32 min_data_hdr_size[8] = {
1555 SHORT_H_SIZE, MCAST_H_SIZE, NAMED_H_SIZE, BASIC_H_SIZE,
1556 MAX_H_SIZE, MAX_H_SIZE, MAX_H_SIZE, MAX_H_SIZE
1557 };
1558
1559 struct tipc_msg *msg;
1560 u32 tipc_hdr[2];
1561 u32 size;
1562 u32 hdr_size;
1563 u32 min_hdr_size;
1564
1565 if (unlikely(buf->len < MIN_H_SIZE))
1566 return 0;
1567
1568 msg = skb_header_pointer(buf, 0, sizeof(tipc_hdr), tipc_hdr);
1569 if (msg == NULL)
1570 return 0;
1571
1572 if (unlikely(msg_version(msg) != TIPC_VERSION))
1573 return 0;
1574
1575 size = msg_size(msg);
1576 hdr_size = msg_hdr_sz(msg);
1577 min_hdr_size = msg_isdata(msg) ?
1578 min_data_hdr_size[msg_type(msg)] : INT_H_SIZE;
1579
1580 if (unlikely((hdr_size < min_hdr_size) ||
1581 (size < hdr_size) ||
1582 (buf->len < size) ||
1583 (size - hdr_size > TIPC_MAX_USER_MSG_SIZE)))
1584 return 0;
1585
1586 return pskb_may_pull(buf, hdr_size);
1587}
1588
1589/**
1590 * tipc_recv_msg - process TIPC messages arriving from off-node
1591 * @head: pointer to message buffer chain
1592 * @tb_ptr: pointer to bearer message arrived on
1593 *
1594 * Invoked with no locks held. Bearer pointer must point to a valid bearer
1595 * structure (i.e. cannot be NULL), but bearer can be inactive.
1596 */
1597void tipc_recv_msg(struct sk_buff *head, struct tipc_bearer *b_ptr)
1598{
1599 read_lock_bh(&tipc_net_lock);
1600 while (head) {
1601 struct tipc_node *n_ptr;
1602 struct tipc_link *l_ptr;
1603 struct sk_buff *crs;
1604 struct sk_buff *buf = head;
1605 struct tipc_msg *msg;
1606 u32 seq_no;
1607 u32 ackd;
1608 u32 released = 0;
1609 int type;
1610
1611 head = head->next;
1612
1613 /* Ensure bearer is still enabled */
1614 if (unlikely(!b_ptr->active))
1615 goto cont;
1616
1617 /* Ensure message is well-formed */
1618 if (unlikely(!link_recv_buf_validate(buf)))
1619 goto cont;
1620
1621 /* Ensure message data is a single contiguous unit */
1622 if (unlikely(skb_linearize(buf)))
1623 goto cont;
1624
1625 /* Handle arrival of a non-unicast link message */
1626 msg = buf_msg(buf);
1627
1628 if (unlikely(msg_non_seq(msg))) {
1629 if (msg_user(msg) == LINK_CONFIG)
1630 tipc_disc_recv_msg(buf, b_ptr);
1631 else
1632 tipc_bclink_recv_pkt(buf);
1633 continue;
1634 }
1635
1636 /* Discard unicast link messages destined for another node */
1637 if (unlikely(!msg_short(msg) &&
1638 (msg_destnode(msg) != tipc_own_addr)))
1639 goto cont;
1640
1641 /* Locate neighboring node that sent message */
1642 n_ptr = tipc_node_find(msg_prevnode(msg));
1643 if (unlikely(!n_ptr))
1644 goto cont;
1645 tipc_node_lock(n_ptr);
1646
1647 /* Locate unicast link endpoint that should handle message */
1648 l_ptr = n_ptr->links[b_ptr->identity];
1649 if (unlikely(!l_ptr)) {
1650 tipc_node_unlock(n_ptr);
1651 goto cont;
1652 }
1653
1654 /* Verify that communication with node is currently allowed */
1655 if ((n_ptr->block_setup & WAIT_PEER_DOWN) &&
1656 msg_user(msg) == LINK_PROTOCOL &&
1657 (msg_type(msg) == RESET_MSG ||
1658 msg_type(msg) == ACTIVATE_MSG) &&
1659 !msg_redundant_link(msg))
1660 n_ptr->block_setup &= ~WAIT_PEER_DOWN;
1661
1662 if (n_ptr->block_setup) {
1663 tipc_node_unlock(n_ptr);
1664 goto cont;
1665 }
1666
1667 /* Validate message sequence number info */
1668 seq_no = msg_seqno(msg);
1669 ackd = msg_ack(msg);
1670
1671 /* Release acked messages */
1672 if (n_ptr->bclink.supported)
1673 tipc_bclink_acknowledge(n_ptr, msg_bcast_ack(msg));
1674
1675 crs = l_ptr->first_out;
1676 while ((crs != l_ptr->next_out) &&
1677 less_eq(buf_seqno(crs), ackd)) {
1678 struct sk_buff *next = crs->next;
1679
1680 kfree_skb(crs);
1681 crs = next;
1682 released++;
1683 }
1684 if (released) {
1685 l_ptr->first_out = crs;
1686 l_ptr->out_queue_size -= released;
1687 }
1688
1689 /* Try sending any messages link endpoint has pending */
1690 if (unlikely(l_ptr->next_out))
1691 tipc_link_push_queue(l_ptr);
1692 if (unlikely(!list_empty(&l_ptr->waiting_ports)))
1693 tipc_link_wakeup_ports(l_ptr, 0);
1694 if (unlikely(++l_ptr->unacked_window >= TIPC_MIN_LINK_WIN)) {
1695 l_ptr->stats.sent_acks++;
1696 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, 0, 0);
1697 }
1698
1699 /* Now (finally!) process the incoming message */
1700protocol_check:
1701 if (likely(link_working_working(l_ptr))) {
1702 if (likely(seq_no == mod(l_ptr->next_in_no))) {
1703 l_ptr->next_in_no++;
1704 if (unlikely(l_ptr->oldest_deferred_in))
1705 head = link_insert_deferred_queue(l_ptr,
1706 head);
1707deliver:
1708 if (likely(msg_isdata(msg))) {
1709 tipc_node_unlock(n_ptr);
1710 tipc_port_recv_msg(buf);
1711 continue;
1712 }
1713 switch (msg_user(msg)) {
1714 int ret;
1715 case MSG_BUNDLER:
1716 l_ptr->stats.recv_bundles++;
1717 l_ptr->stats.recv_bundled +=
1718 msg_msgcnt(msg);
1719 tipc_node_unlock(n_ptr);
1720 tipc_link_recv_bundle(buf);
1721 continue;
1722 case NAME_DISTRIBUTOR:
1723 tipc_node_unlock(n_ptr);
1724 tipc_named_recv(buf);
1725 continue;
1726 case CONN_MANAGER:
1727 tipc_node_unlock(n_ptr);
1728 tipc_port_recv_proto_msg(buf);
1729 continue;
1730 case MSG_FRAGMENTER:
1731 l_ptr->stats.recv_fragments++;
1732 ret = tipc_link_recv_fragment(
1733 &l_ptr->defragm_buf,
1734 &buf, &msg);
1735 if (ret == 1) {
1736 l_ptr->stats.recv_fragmented++;
1737 goto deliver;
1738 }
1739 if (ret == -1)
1740 l_ptr->next_in_no--;
1741 break;
1742 case CHANGEOVER_PROTOCOL:
1743 type = msg_type(msg);
1744 if (link_recv_changeover_msg(&l_ptr,
1745 &buf)) {
1746 msg = buf_msg(buf);
1747 seq_no = msg_seqno(msg);
1748 if (type == ORIGINAL_MSG)
1749 goto deliver;
1750 goto protocol_check;
1751 }
1752 break;
1753 default:
1754 kfree_skb(buf);
1755 buf = NULL;
1756 break;
1757 }
1758 tipc_node_unlock(n_ptr);
1759 tipc_net_route_msg(buf);
1760 continue;
1761 }
1762 link_handle_out_of_seq_msg(l_ptr, buf);
1763 head = link_insert_deferred_queue(l_ptr, head);
1764 tipc_node_unlock(n_ptr);
1765 continue;
1766 }
1767
1768 if (msg_user(msg) == LINK_PROTOCOL) {
1769 link_recv_proto_msg(l_ptr, buf);
1770 head = link_insert_deferred_queue(l_ptr, head);
1771 tipc_node_unlock(n_ptr);
1772 continue;
1773 }
1774 link_state_event(l_ptr, TRAFFIC_MSG_EVT);
1775
1776 if (link_working_working(l_ptr)) {
1777 /* Re-insert in front of queue */
1778 buf->next = head;
1779 head = buf;
1780 tipc_node_unlock(n_ptr);
1781 continue;
1782 }
1783 tipc_node_unlock(n_ptr);
1784cont:
1785 kfree_skb(buf);
1786 }
1787 read_unlock_bh(&tipc_net_lock);
1788}
1789
1790/*
1791 * tipc_link_defer_pkt - Add out-of-sequence message to deferred reception queue
1792 *
1793 * Returns increase in queue length (i.e. 0 or 1)
1794 */
1795u32 tipc_link_defer_pkt(struct sk_buff **head, struct sk_buff **tail,
1796 struct sk_buff *buf)
1797{
1798 struct sk_buff *queue_buf;
1799 struct sk_buff **prev;
1800 u32 seq_no = buf_seqno(buf);
1801
1802 buf->next = NULL;
1803
1804 /* Empty queue ? */
1805 if (*head == NULL) {
1806 *head = *tail = buf;
1807 return 1;
1808 }
1809
1810 /* Last ? */
1811 if (less(buf_seqno(*tail), seq_no)) {
1812 (*tail)->next = buf;
1813 *tail = buf;
1814 return 1;
1815 }
1816
1817 /* Locate insertion point in queue, then insert; discard if duplicate */
1818 prev = head;
1819 queue_buf = *head;
1820 for (;;) {
1821 u32 curr_seqno = buf_seqno(queue_buf);
1822
1823 if (seq_no == curr_seqno) {
1824 kfree_skb(buf);
1825 return 0;
1826 }
1827
1828 if (less(seq_no, curr_seqno))
1829 break;
1830
1831 prev = &queue_buf->next;
1832 queue_buf = queue_buf->next;
1833 }
1834
1835 buf->next = queue_buf;
1836 *prev = buf;
1837 return 1;
1838}
1839
1840/*
1841 * link_handle_out_of_seq_msg - handle arrival of out-of-sequence packet
1842 */
1843static void link_handle_out_of_seq_msg(struct tipc_link *l_ptr,
1844 struct sk_buff *buf)
1845{
1846 u32 seq_no = buf_seqno(buf);
1847
1848 if (likely(msg_user(buf_msg(buf)) == LINK_PROTOCOL)) {
1849 link_recv_proto_msg(l_ptr, buf);
1850 return;
1851 }
1852
1853 /* Record OOS packet arrival (force mismatch on next timeout) */
1854 l_ptr->checkpoint--;
1855
1856 /*
1857 * Discard packet if a duplicate; otherwise add it to deferred queue
1858 * and notify peer of gap as per protocol specification
1859 */
1860 if (less(seq_no, mod(l_ptr->next_in_no))) {
1861 l_ptr->stats.duplicates++;
1862 kfree_skb(buf);
1863 return;
1864 }
1865
1866 if (tipc_link_defer_pkt(&l_ptr->oldest_deferred_in,
1867 &l_ptr->newest_deferred_in, buf)) {
1868 l_ptr->deferred_inqueue_sz++;
1869 l_ptr->stats.deferred_recv++;
1870 if ((l_ptr->deferred_inqueue_sz % 16) == 1)
1871 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, 0, 0);
1872 } else
1873 l_ptr->stats.duplicates++;
1874}
1875
1876/*
1877 * Send protocol message to the other endpoint.
1878 */
1879void tipc_link_send_proto_msg(struct tipc_link *l_ptr, u32 msg_typ,
1880 int probe_msg, u32 gap, u32 tolerance,
1881 u32 priority, u32 ack_mtu)
1882{
1883 struct sk_buff *buf = NULL;
1884 struct tipc_msg *msg = l_ptr->pmsg;
1885 u32 msg_size = sizeof(l_ptr->proto_msg);
1886 int r_flag;
1887
1888 /* Discard any previous message that was deferred due to congestion */
1889 if (l_ptr->proto_msg_queue) {
1890 kfree_skb(l_ptr->proto_msg_queue);
1891 l_ptr->proto_msg_queue = NULL;
1892 }
1893
1894 if (link_blocked(l_ptr))
1895 return;
1896
1897 /* Abort non-RESET send if communication with node is prohibited */
1898 if ((l_ptr->owner->block_setup) && (msg_typ != RESET_MSG))
1899 return;
1900
1901 /* Create protocol message with "out-of-sequence" sequence number */
1902 msg_set_type(msg, msg_typ);
1903 msg_set_net_plane(msg, l_ptr->b_ptr->net_plane);
1904 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1905 msg_set_last_bcast(msg, tipc_bclink_get_last_sent());
1906
1907 if (msg_typ == STATE_MSG) {
1908 u32 next_sent = mod(l_ptr->next_out_no);
1909
1910 if (!tipc_link_is_up(l_ptr))
1911 return;
1912 if (l_ptr->next_out)
1913 next_sent = buf_seqno(l_ptr->next_out);
1914 msg_set_next_sent(msg, next_sent);
1915 if (l_ptr->oldest_deferred_in) {
1916 u32 rec = buf_seqno(l_ptr->oldest_deferred_in);
1917 gap = mod(rec - mod(l_ptr->next_in_no));
1918 }
1919 msg_set_seq_gap(msg, gap);
1920 if (gap)
1921 l_ptr->stats.sent_nacks++;
1922 msg_set_link_tolerance(msg, tolerance);
1923 msg_set_linkprio(msg, priority);
1924 msg_set_max_pkt(msg, ack_mtu);
1925 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
1926 msg_set_probe(msg, probe_msg != 0);
1927 if (probe_msg) {
1928 u32 mtu = l_ptr->max_pkt;
1929
1930 if ((mtu < l_ptr->max_pkt_target) &&
1931 link_working_working(l_ptr) &&
1932 l_ptr->fsm_msg_cnt) {
1933 msg_size = (mtu + (l_ptr->max_pkt_target - mtu)/2 + 2) & ~3;
1934 if (l_ptr->max_pkt_probes == 10) {
1935 l_ptr->max_pkt_target = (msg_size - 4);
1936 l_ptr->max_pkt_probes = 0;
1937 msg_size = (mtu + (l_ptr->max_pkt_target - mtu)/2 + 2) & ~3;
1938 }
1939 l_ptr->max_pkt_probes++;
1940 }
1941
1942 l_ptr->stats.sent_probes++;
1943 }
1944 l_ptr->stats.sent_states++;
1945 } else { /* RESET_MSG or ACTIVATE_MSG */
1946 msg_set_ack(msg, mod(l_ptr->reset_checkpoint - 1));
1947 msg_set_seq_gap(msg, 0);
1948 msg_set_next_sent(msg, 1);
1949 msg_set_probe(msg, 0);
1950 msg_set_link_tolerance(msg, l_ptr->tolerance);
1951 msg_set_linkprio(msg, l_ptr->priority);
1952 msg_set_max_pkt(msg, l_ptr->max_pkt_target);
1953 }
1954
1955 r_flag = (l_ptr->owner->working_links > tipc_link_is_up(l_ptr));
1956 msg_set_redundant_link(msg, r_flag);
1957 msg_set_linkprio(msg, l_ptr->priority);
1958 msg_set_size(msg, msg_size);
1959
1960 msg_set_seqno(msg, mod(l_ptr->next_out_no + (0xffff/2)));
1961
1962 buf = tipc_buf_acquire(msg_size);
1963 if (!buf)
1964 return;
1965
1966 skb_copy_to_linear_data(buf, msg, sizeof(l_ptr->proto_msg));
1967
1968 /* Defer message if bearer is already congested */
1969 if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr)) {
1970 l_ptr->proto_msg_queue = buf;
1971 return;
1972 }
1973
1974 /* Defer message if attempting to send results in bearer congestion */
1975 if (!tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) {
1976 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr);
1977 l_ptr->proto_msg_queue = buf;
1978 l_ptr->stats.bearer_congs++;
1979 return;
1980 }
1981
1982 /* Discard message if it was sent successfully */
1983 l_ptr->unacked_window = 0;
1984 kfree_skb(buf);
1985}
1986
1987/*
1988 * Receive protocol message :
1989 * Note that network plane id propagates through the network, and may
1990 * change at any time. The node with lowest address rules
1991 */
1992static void link_recv_proto_msg(struct tipc_link *l_ptr, struct sk_buff *buf)
1993{
1994 u32 rec_gap = 0;
1995 u32 max_pkt_info;
1996 u32 max_pkt_ack;
1997 u32 msg_tol;
1998 struct tipc_msg *msg = buf_msg(buf);
1999
2000 if (link_blocked(l_ptr))
2001 goto exit;
2002
2003 /* record unnumbered packet arrival (force mismatch on next timeout) */
2004 l_ptr->checkpoint--;
2005
2006 if (l_ptr->b_ptr->net_plane != msg_net_plane(msg))
2007 if (tipc_own_addr > msg_prevnode(msg))
2008 l_ptr->b_ptr->net_plane = msg_net_plane(msg);
2009
2010 l_ptr->owner->permit_changeover = msg_redundant_link(msg);
2011
2012 switch (msg_type(msg)) {
2013
2014 case RESET_MSG:
2015 if (!link_working_unknown(l_ptr) &&
2016 (l_ptr->peer_session != INVALID_SESSION)) {
2017 if (less_eq(msg_session(msg), l_ptr->peer_session))
2018 break; /* duplicate or old reset: ignore */
2019 }
2020
2021 if (!msg_redundant_link(msg) && (link_working_working(l_ptr) ||
2022 link_working_unknown(l_ptr))) {
2023 /*
2024 * peer has lost contact -- don't allow peer's links
2025 * to reactivate before we recognize loss & clean up
2026 */
2027 l_ptr->owner->block_setup = WAIT_NODE_DOWN;
2028 }
2029
2030 link_state_event(l_ptr, RESET_MSG);
2031
2032 /* fall thru' */
2033 case ACTIVATE_MSG:
2034 /* Update link settings according other endpoint's values */
2035 strcpy((strrchr(l_ptr->name, ':') + 1), (char *)msg_data(msg));
2036
2037 msg_tol = msg_link_tolerance(msg);
2038 if (msg_tol > l_ptr->tolerance)
2039 link_set_supervision_props(l_ptr, msg_tol);
2040
2041 if (msg_linkprio(msg) > l_ptr->priority)
2042 l_ptr->priority = msg_linkprio(msg);
2043
2044 max_pkt_info = msg_max_pkt(msg);
2045 if (max_pkt_info) {
2046 if (max_pkt_info < l_ptr->max_pkt_target)
2047 l_ptr->max_pkt_target = max_pkt_info;
2048 if (l_ptr->max_pkt > l_ptr->max_pkt_target)
2049 l_ptr->max_pkt = l_ptr->max_pkt_target;
2050 } else {
2051 l_ptr->max_pkt = l_ptr->max_pkt_target;
2052 }
2053 l_ptr->owner->bclink.supportable = (max_pkt_info != 0);
2054
2055 /* Synchronize broadcast link info, if not done previously */
2056 if (!tipc_node_is_up(l_ptr->owner)) {
2057 l_ptr->owner->bclink.last_sent =
2058 l_ptr->owner->bclink.last_in =
2059 msg_last_bcast(msg);
2060 l_ptr->owner->bclink.oos_state = 0;
2061 }
2062
2063 l_ptr->peer_session = msg_session(msg);
2064 l_ptr->peer_bearer_id = msg_bearer_id(msg);
2065
2066 if (msg_type(msg) == ACTIVATE_MSG)
2067 link_state_event(l_ptr, ACTIVATE_MSG);
2068 break;
2069 case STATE_MSG:
2070
2071 msg_tol = msg_link_tolerance(msg);
2072 if (msg_tol)
2073 link_set_supervision_props(l_ptr, msg_tol);
2074
2075 if (msg_linkprio(msg) &&
2076 (msg_linkprio(msg) != l_ptr->priority)) {
2077 warn("Resetting link <%s>, priority change %u->%u\n",
2078 l_ptr->name, l_ptr->priority, msg_linkprio(msg));
2079 l_ptr->priority = msg_linkprio(msg);
2080 tipc_link_reset(l_ptr); /* Enforce change to take effect */
2081 break;
2082 }
2083 link_state_event(l_ptr, TRAFFIC_MSG_EVT);
2084 l_ptr->stats.recv_states++;
2085 if (link_reset_unknown(l_ptr))
2086 break;
2087
2088 if (less_eq(mod(l_ptr->next_in_no), msg_next_sent(msg))) {
2089 rec_gap = mod(msg_next_sent(msg) -
2090 mod(l_ptr->next_in_no));
2091 }
2092
2093 max_pkt_ack = msg_max_pkt(msg);
2094 if (max_pkt_ack > l_ptr->max_pkt) {
2095 l_ptr->max_pkt = max_pkt_ack;
2096 l_ptr->max_pkt_probes = 0;
2097 }
2098
2099 max_pkt_ack = 0;
2100 if (msg_probe(msg)) {
2101 l_ptr->stats.recv_probes++;
2102 if (msg_size(msg) > sizeof(l_ptr->proto_msg))
2103 max_pkt_ack = msg_size(msg);
2104 }
2105
2106 /* Protocol message before retransmits, reduce loss risk */
2107 if (l_ptr->owner->bclink.supported)
2108 tipc_bclink_update_link_state(l_ptr->owner,
2109 msg_last_bcast(msg));
2110
2111 if (rec_gap || (msg_probe(msg))) {
2112 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
2113 0, rec_gap, 0, 0, max_pkt_ack);
2114 }
2115 if (msg_seq_gap(msg)) {
2116 l_ptr->stats.recv_nacks++;
2117 tipc_link_retransmit(l_ptr, l_ptr->first_out,
2118 msg_seq_gap(msg));
2119 }
2120 break;
2121 }
2122exit:
2123 kfree_skb(buf);
2124}
2125
2126
2127/*
2128 * tipc_link_tunnel(): Send one message via a link belonging to
2129 * another bearer. Owner node is locked.
2130 */
2131static void tipc_link_tunnel(struct tipc_link *l_ptr,
2132 struct tipc_msg *tunnel_hdr,
2133 struct tipc_msg *msg,
2134 u32 selector)
2135{
2136 struct tipc_link *tunnel;
2137 struct sk_buff *buf;
2138 u32 length = msg_size(msg);
2139
2140 tunnel = l_ptr->owner->active_links[selector & 1];
2141 if (!tipc_link_is_up(tunnel)) {
2142 warn("Link changeover error, "
2143 "tunnel link no longer available\n");
2144 return;
2145 }
2146 msg_set_size(tunnel_hdr, length + INT_H_SIZE);
2147 buf = tipc_buf_acquire(length + INT_H_SIZE);
2148 if (!buf) {
2149 warn("Link changeover error, "
2150 "unable to send tunnel msg\n");
2151 return;
2152 }
2153 skb_copy_to_linear_data(buf, tunnel_hdr, INT_H_SIZE);
2154 skb_copy_to_linear_data_offset(buf, INT_H_SIZE, msg, length);
2155 tipc_link_send_buf(tunnel, buf);
2156}
2157
2158
2159
2160/*
2161 * changeover(): Send whole message queue via the remaining link
2162 * Owner node is locked.
2163 */
2164void tipc_link_changeover(struct tipc_link *l_ptr)
2165{
2166 u32 msgcount = l_ptr->out_queue_size;
2167 struct sk_buff *crs = l_ptr->first_out;
2168 struct tipc_link *tunnel = l_ptr->owner->active_links[0];
2169 struct tipc_msg tunnel_hdr;
2170 int split_bundles;
2171
2172 if (!tunnel)
2173 return;
2174
2175 if (!l_ptr->owner->permit_changeover) {
2176 warn("Link changeover error, "
2177 "peer did not permit changeover\n");
2178 return;
2179 }
2180
2181 tipc_msg_init(&tunnel_hdr, CHANGEOVER_PROTOCOL,
2182 ORIGINAL_MSG, INT_H_SIZE, l_ptr->addr);
2183 msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id);
2184 msg_set_msgcnt(&tunnel_hdr, msgcount);
2185
2186 if (!l_ptr->first_out) {
2187 struct sk_buff *buf;
2188
2189 buf = tipc_buf_acquire(INT_H_SIZE);
2190 if (buf) {
2191 skb_copy_to_linear_data(buf, &tunnel_hdr, INT_H_SIZE);
2192 msg_set_size(&tunnel_hdr, INT_H_SIZE);
2193 tipc_link_send_buf(tunnel, buf);
2194 } else {
2195 warn("Link changeover error, "
2196 "unable to send changeover msg\n");
2197 }
2198 return;
2199 }
2200
2201 split_bundles = (l_ptr->owner->active_links[0] !=
2202 l_ptr->owner->active_links[1]);
2203
2204 while (crs) {
2205 struct tipc_msg *msg = buf_msg(crs);
2206
2207 if ((msg_user(msg) == MSG_BUNDLER) && split_bundles) {
2208 struct tipc_msg *m = msg_get_wrapped(msg);
2209 unchar *pos = (unchar *)m;
2210
2211 msgcount = msg_msgcnt(msg);
2212 while (msgcount--) {
2213 msg_set_seqno(m, msg_seqno(msg));
2214 tipc_link_tunnel(l_ptr, &tunnel_hdr, m,
2215 msg_link_selector(m));
2216 pos += align(msg_size(m));
2217 m = (struct tipc_msg *)pos;
2218 }
2219 } else {
2220 tipc_link_tunnel(l_ptr, &tunnel_hdr, msg,
2221 msg_link_selector(msg));
2222 }
2223 crs = crs->next;
2224 }
2225}
2226
2227void tipc_link_send_duplicate(struct tipc_link *l_ptr, struct tipc_link *tunnel)
2228{
2229 struct sk_buff *iter;
2230 struct tipc_msg tunnel_hdr;
2231
2232 tipc_msg_init(&tunnel_hdr, CHANGEOVER_PROTOCOL,
2233 DUPLICATE_MSG, INT_H_SIZE, l_ptr->addr);
2234 msg_set_msgcnt(&tunnel_hdr, l_ptr->out_queue_size);
2235 msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id);
2236 iter = l_ptr->first_out;
2237 while (iter) {
2238 struct sk_buff *outbuf;
2239 struct tipc_msg *msg = buf_msg(iter);
2240 u32 length = msg_size(msg);
2241
2242 if (msg_user(msg) == MSG_BUNDLER)
2243 msg_set_type(msg, CLOSED_MSG);
2244 msg_set_ack(msg, mod(l_ptr->next_in_no - 1)); /* Update */
2245 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
2246 msg_set_size(&tunnel_hdr, length + INT_H_SIZE);
2247 outbuf = tipc_buf_acquire(length + INT_H_SIZE);
2248 if (outbuf == NULL) {
2249 warn("Link changeover error, "
2250 "unable to send duplicate msg\n");
2251 return;
2252 }
2253 skb_copy_to_linear_data(outbuf, &tunnel_hdr, INT_H_SIZE);
2254 skb_copy_to_linear_data_offset(outbuf, INT_H_SIZE, iter->data,
2255 length);
2256 tipc_link_send_buf(tunnel, outbuf);
2257 if (!tipc_link_is_up(l_ptr))
2258 return;
2259 iter = iter->next;
2260 }
2261}
2262
2263/**
2264 * buf_extract - extracts embedded TIPC message from another message
2265 * @skb: encapsulating message buffer
2266 * @from_pos: offset to extract from
2267 *
2268 * Returns a new message buffer containing an embedded message. The
2269 * encapsulating message itself is left unchanged.
2270 */
2271static struct sk_buff *buf_extract(struct sk_buff *skb, u32 from_pos)
2272{
2273 struct tipc_msg *msg = (struct tipc_msg *)(skb->data + from_pos);
2274 u32 size = msg_size(msg);
2275 struct sk_buff *eb;
2276
2277 eb = tipc_buf_acquire(size);
2278 if (eb)
2279 skb_copy_to_linear_data(eb, msg, size);
2280 return eb;
2281}
2282
2283/*
2284 * link_recv_changeover_msg(): Receive tunneled packet sent
2285 * via other link. Node is locked. Return extracted buffer.
2286 */
2287static int link_recv_changeover_msg(struct tipc_link **l_ptr,
2288 struct sk_buff **buf)
2289{
2290 struct sk_buff *tunnel_buf = *buf;
2291 struct tipc_link *dest_link;
2292 struct tipc_msg *msg;
2293 struct tipc_msg *tunnel_msg = buf_msg(tunnel_buf);
2294 u32 msg_typ = msg_type(tunnel_msg);
2295 u32 msg_count = msg_msgcnt(tunnel_msg);
2296
2297 dest_link = (*l_ptr)->owner->links[msg_bearer_id(tunnel_msg)];
2298 if (!dest_link)
2299 goto exit;
2300 if (dest_link == *l_ptr) {
2301 err("Unexpected changeover message on link <%s>\n",
2302 (*l_ptr)->name);
2303 goto exit;
2304 }
2305 *l_ptr = dest_link;
2306 msg = msg_get_wrapped(tunnel_msg);
2307
2308 if (msg_typ == DUPLICATE_MSG) {
2309 if (less(msg_seqno(msg), mod(dest_link->next_in_no)))
2310 goto exit;
2311 *buf = buf_extract(tunnel_buf, INT_H_SIZE);
2312 if (*buf == NULL) {
2313 warn("Link changeover error, duplicate msg dropped\n");
2314 goto exit;
2315 }
2316 kfree_skb(tunnel_buf);
2317 return 1;
2318 }
2319
2320 /* First original message ?: */
2321 if (tipc_link_is_up(dest_link)) {
2322 info("Resetting link <%s>, changeover initiated by peer\n",
2323 dest_link->name);
2324 tipc_link_reset(dest_link);
2325 dest_link->exp_msg_count = msg_count;
2326 if (!msg_count)
2327 goto exit;
2328 } else if (dest_link->exp_msg_count == START_CHANGEOVER) {
2329 dest_link->exp_msg_count = msg_count;
2330 if (!msg_count)
2331 goto exit;
2332 }
2333
2334 /* Receive original message */
2335 if (dest_link->exp_msg_count == 0) {
2336 warn("Link switchover error, "
2337 "got too many tunnelled messages\n");
2338 goto exit;
2339 }
2340 dest_link->exp_msg_count--;
2341 if (less(msg_seqno(msg), dest_link->reset_checkpoint)) {
2342 goto exit;
2343 } else {
2344 *buf = buf_extract(tunnel_buf, INT_H_SIZE);
2345 if (*buf != NULL) {
2346 kfree_skb(tunnel_buf);
2347 return 1;
2348 } else {
2349 warn("Link changeover error, original msg dropped\n");
2350 }
2351 }
2352exit:
2353 *buf = NULL;
2354 kfree_skb(tunnel_buf);
2355 return 0;
2356}
2357
2358/*
2359 * Bundler functionality:
2360 */
2361void tipc_link_recv_bundle(struct sk_buff *buf)
2362{
2363 u32 msgcount = msg_msgcnt(buf_msg(buf));
2364 u32 pos = INT_H_SIZE;
2365 struct sk_buff *obuf;
2366
2367 while (msgcount--) {
2368 obuf = buf_extract(buf, pos);
2369 if (obuf == NULL) {
2370 warn("Link unable to unbundle message(s)\n");
2371 break;
2372 }
2373 pos += align(msg_size(buf_msg(obuf)));
2374 tipc_net_route_msg(obuf);
2375 }
2376 kfree_skb(buf);
2377}
2378
2379/*
2380 * Fragmentation/defragmentation:
2381 */
2382
2383/*
2384 * link_send_long_buf: Entry for buffers needing fragmentation.
2385 * The buffer is complete, inclusive total message length.
2386 * Returns user data length.
2387 */
2388static int link_send_long_buf(struct tipc_link *l_ptr, struct sk_buff *buf)
2389{
2390 struct sk_buff *buf_chain = NULL;
2391 struct sk_buff *buf_chain_tail = (struct sk_buff *)&buf_chain;
2392 struct tipc_msg *inmsg = buf_msg(buf);
2393 struct tipc_msg fragm_hdr;
2394 u32 insize = msg_size(inmsg);
2395 u32 dsz = msg_data_sz(inmsg);
2396 unchar *crs = buf->data;
2397 u32 rest = insize;
2398 u32 pack_sz = l_ptr->max_pkt;
2399 u32 fragm_sz = pack_sz - INT_H_SIZE;
2400 u32 fragm_no = 0;
2401 u32 destaddr;
2402
2403 if (msg_short(inmsg))
2404 destaddr = l_ptr->addr;
2405 else
2406 destaddr = msg_destnode(inmsg);
2407
2408 /* Prepare reusable fragment header: */
2409 tipc_msg_init(&fragm_hdr, MSG_FRAGMENTER, FIRST_FRAGMENT,
2410 INT_H_SIZE, destaddr);
2411
2412 /* Chop up message: */
2413 while (rest > 0) {
2414 struct sk_buff *fragm;
2415
2416 if (rest <= fragm_sz) {
2417 fragm_sz = rest;
2418 msg_set_type(&fragm_hdr, LAST_FRAGMENT);
2419 }
2420 fragm = tipc_buf_acquire(fragm_sz + INT_H_SIZE);
2421 if (fragm == NULL) {
2422 kfree_skb(buf);
2423 while (buf_chain) {
2424 buf = buf_chain;
2425 buf_chain = buf_chain->next;
2426 kfree_skb(buf);
2427 }
2428 return -ENOMEM;
2429 }
2430 msg_set_size(&fragm_hdr, fragm_sz + INT_H_SIZE);
2431 fragm_no++;
2432 msg_set_fragm_no(&fragm_hdr, fragm_no);
2433 skb_copy_to_linear_data(fragm, &fragm_hdr, INT_H_SIZE);
2434 skb_copy_to_linear_data_offset(fragm, INT_H_SIZE, crs,
2435 fragm_sz);
2436 buf_chain_tail->next = fragm;
2437 buf_chain_tail = fragm;
2438
2439 rest -= fragm_sz;
2440 crs += fragm_sz;
2441 msg_set_type(&fragm_hdr, FRAGMENT);
2442 }
2443 kfree_skb(buf);
2444
2445 /* Append chain of fragments to send queue & send them */
2446 l_ptr->long_msg_seq_no++;
2447 link_add_chain_to_outqueue(l_ptr, buf_chain, l_ptr->long_msg_seq_no);
2448 l_ptr->stats.sent_fragments += fragm_no;
2449 l_ptr->stats.sent_fragmented++;
2450 tipc_link_push_queue(l_ptr);
2451
2452 return dsz;
2453}
2454
2455/*
2456 * A pending message being re-assembled must store certain values
2457 * to handle subsequent fragments correctly. The following functions
2458 * help storing these values in unused, available fields in the
2459 * pending message. This makes dynamic memory allocation unnecessary.
2460 */
2461static void set_long_msg_seqno(struct sk_buff *buf, u32 seqno)
2462{
2463 msg_set_seqno(buf_msg(buf), seqno);
2464}
2465
2466static u32 get_fragm_size(struct sk_buff *buf)
2467{
2468 return msg_ack(buf_msg(buf));
2469}
2470
2471static void set_fragm_size(struct sk_buff *buf, u32 sz)
2472{
2473 msg_set_ack(buf_msg(buf), sz);
2474}
2475
2476static u32 get_expected_frags(struct sk_buff *buf)
2477{
2478 return msg_bcast_ack(buf_msg(buf));
2479}
2480
2481static void set_expected_frags(struct sk_buff *buf, u32 exp)
2482{
2483 msg_set_bcast_ack(buf_msg(buf), exp);
2484}
2485
2486static u32 get_timer_cnt(struct sk_buff *buf)
2487{
2488 return msg_reroute_cnt(buf_msg(buf));
2489}
2490
2491static void incr_timer_cnt(struct sk_buff *buf)
2492{
2493 msg_incr_reroute_cnt(buf_msg(buf));
2494}
2495
2496/*
2497 * tipc_link_recv_fragment(): Called with node lock on. Returns
2498 * the reassembled buffer if message is complete.
2499 */
2500int tipc_link_recv_fragment(struct sk_buff **pending, struct sk_buff **fb,
2501 struct tipc_msg **m)
2502{
2503 struct sk_buff *prev = NULL;
2504 struct sk_buff *fbuf = *fb;
2505 struct tipc_msg *fragm = buf_msg(fbuf);
2506 struct sk_buff *pbuf = *pending;
2507 u32 long_msg_seq_no = msg_long_msgno(fragm);
2508
2509 *fb = NULL;
2510
2511 /* Is there an incomplete message waiting for this fragment? */
2512 while (pbuf && ((buf_seqno(pbuf) != long_msg_seq_no) ||
2513 (msg_orignode(fragm) != msg_orignode(buf_msg(pbuf))))) {
2514 prev = pbuf;
2515 pbuf = pbuf->next;
2516 }
2517
2518 if (!pbuf && (msg_type(fragm) == FIRST_FRAGMENT)) {
2519 struct tipc_msg *imsg = (struct tipc_msg *)msg_data(fragm);
2520 u32 msg_sz = msg_size(imsg);
2521 u32 fragm_sz = msg_data_sz(fragm);
2522 u32 exp_fragm_cnt = msg_sz/fragm_sz + !!(msg_sz % fragm_sz);
2523 u32 max = TIPC_MAX_USER_MSG_SIZE + NAMED_H_SIZE;
2524 if (msg_type(imsg) == TIPC_MCAST_MSG)
2525 max = TIPC_MAX_USER_MSG_SIZE + MCAST_H_SIZE;
2526 if (msg_size(imsg) > max) {
2527 kfree_skb(fbuf);
2528 return 0;
2529 }
2530 pbuf = tipc_buf_acquire(msg_size(imsg));
2531 if (pbuf != NULL) {
2532 pbuf->next = *pending;
2533 *pending = pbuf;
2534 skb_copy_to_linear_data(pbuf, imsg,
2535 msg_data_sz(fragm));
2536 /* Prepare buffer for subsequent fragments. */
2537 set_long_msg_seqno(pbuf, long_msg_seq_no);
2538 set_fragm_size(pbuf, fragm_sz);
2539 set_expected_frags(pbuf, exp_fragm_cnt - 1);
2540 } else {
2541 dbg("Link unable to reassemble fragmented message\n");
2542 kfree_skb(fbuf);
2543 return -1;
2544 }
2545 kfree_skb(fbuf);
2546 return 0;
2547 } else if (pbuf && (msg_type(fragm) != FIRST_FRAGMENT)) {
2548 u32 dsz = msg_data_sz(fragm);
2549 u32 fsz = get_fragm_size(pbuf);
2550 u32 crs = ((msg_fragm_no(fragm) - 1) * fsz);
2551 u32 exp_frags = get_expected_frags(pbuf) - 1;
2552 skb_copy_to_linear_data_offset(pbuf, crs,
2553 msg_data(fragm), dsz);
2554 kfree_skb(fbuf);
2555
2556 /* Is message complete? */
2557 if (exp_frags == 0) {
2558 if (prev)
2559 prev->next = pbuf->next;
2560 else
2561 *pending = pbuf->next;
2562 msg_reset_reroute_cnt(buf_msg(pbuf));
2563 *fb = pbuf;
2564 *m = buf_msg(pbuf);
2565 return 1;
2566 }
2567 set_expected_frags(pbuf, exp_frags);
2568 return 0;
2569 }
2570 kfree_skb(fbuf);
2571 return 0;
2572}
2573
2574/**
2575 * link_check_defragm_bufs - flush stale incoming message fragments
2576 * @l_ptr: pointer to link
2577 */
2578static void link_check_defragm_bufs(struct tipc_link *l_ptr)
2579{
2580 struct sk_buff *prev = NULL;
2581 struct sk_buff *next = NULL;
2582 struct sk_buff *buf = l_ptr->defragm_buf;
2583
2584 if (!buf)
2585 return;
2586 if (!link_working_working(l_ptr))
2587 return;
2588 while (buf) {
2589 u32 cnt = get_timer_cnt(buf);
2590
2591 next = buf->next;
2592 if (cnt < 4) {
2593 incr_timer_cnt(buf);
2594 prev = buf;
2595 } else {
2596 if (prev)
2597 prev->next = buf->next;
2598 else
2599 l_ptr->defragm_buf = buf->next;
2600 kfree_skb(buf);
2601 }
2602 buf = next;
2603 }
2604}
2605
2606static void link_set_supervision_props(struct tipc_link *l_ptr, u32 tolerance)
2607{
2608 if ((tolerance < TIPC_MIN_LINK_TOL) || (tolerance > TIPC_MAX_LINK_TOL))
2609 return;
2610
2611 l_ptr->tolerance = tolerance;
2612 l_ptr->continuity_interval =
2613 ((tolerance / 4) > 500) ? 500 : tolerance / 4;
2614 l_ptr->abort_limit = tolerance / (l_ptr->continuity_interval / 4);
2615}
2616
2617void tipc_link_set_queue_limits(struct tipc_link *l_ptr, u32 window)
2618{
2619 /* Data messages from this node, inclusive FIRST_FRAGM */
2620 l_ptr->queue_limit[TIPC_LOW_IMPORTANCE] = window;
2621 l_ptr->queue_limit[TIPC_MEDIUM_IMPORTANCE] = (window / 3) * 4;
2622 l_ptr->queue_limit[TIPC_HIGH_IMPORTANCE] = (window / 3) * 5;
2623 l_ptr->queue_limit[TIPC_CRITICAL_IMPORTANCE] = (window / 3) * 6;
2624 /* Transiting data messages,inclusive FIRST_FRAGM */
2625 l_ptr->queue_limit[TIPC_LOW_IMPORTANCE + 4] = 300;
2626 l_ptr->queue_limit[TIPC_MEDIUM_IMPORTANCE + 4] = 600;
2627 l_ptr->queue_limit[TIPC_HIGH_IMPORTANCE + 4] = 900;
2628 l_ptr->queue_limit[TIPC_CRITICAL_IMPORTANCE + 4] = 1200;
2629 l_ptr->queue_limit[CONN_MANAGER] = 1200;
2630 l_ptr->queue_limit[CHANGEOVER_PROTOCOL] = 2500;
2631 l_ptr->queue_limit[NAME_DISTRIBUTOR] = 3000;
2632 /* FRAGMENT and LAST_FRAGMENT packets */
2633 l_ptr->queue_limit[MSG_FRAGMENTER] = 4000;
2634}
2635
2636/**
2637 * link_find_link - locate link by name
2638 * @name - ptr to link name string
2639 * @node - ptr to area to be filled with ptr to associated node
2640 *
2641 * Caller must hold 'tipc_net_lock' to ensure node and bearer are not deleted;
2642 * this also prevents link deletion.
2643 *
2644 * Returns pointer to link (or 0 if invalid link name).
2645 */
2646static struct tipc_link *link_find_link(const char *name,
2647 struct tipc_node **node)
2648{
2649 struct tipc_link_name link_name_parts;
2650 struct tipc_bearer *b_ptr;
2651 struct tipc_link *l_ptr;
2652
2653 if (!link_name_validate(name, &link_name_parts))
2654 return NULL;
2655
2656 b_ptr = tipc_bearer_find_interface(link_name_parts.if_local);
2657 if (!b_ptr)
2658 return NULL;
2659
2660 *node = tipc_node_find(link_name_parts.addr_peer);
2661 if (!*node)
2662 return NULL;
2663
2664 l_ptr = (*node)->links[b_ptr->identity];
2665 if (!l_ptr || strcmp(l_ptr->name, name))
2666 return NULL;
2667
2668 return l_ptr;
2669}
2670
2671/**
2672 * link_value_is_valid -- validate proposed link tolerance/priority/window
2673 *
2674 * @cmd - value type (TIPC_CMD_SET_LINK_*)
2675 * @new_value - the new value
2676 *
2677 * Returns 1 if value is within range, 0 if not.
2678 */
2679static int link_value_is_valid(u16 cmd, u32 new_value)
2680{
2681 switch (cmd) {
2682 case TIPC_CMD_SET_LINK_TOL:
2683 return (new_value >= TIPC_MIN_LINK_TOL) &&
2684 (new_value <= TIPC_MAX_LINK_TOL);
2685 case TIPC_CMD_SET_LINK_PRI:
2686 return (new_value <= TIPC_MAX_LINK_PRI);
2687 case TIPC_CMD_SET_LINK_WINDOW:
2688 return (new_value >= TIPC_MIN_LINK_WIN) &&
2689 (new_value <= TIPC_MAX_LINK_WIN);
2690 }
2691 return 0;
2692}
2693
2694/**
2695 * link_cmd_set_value - change priority/tolerance/window for link/bearer/media
2696 * @name - ptr to link, bearer, or media name
2697 * @new_value - new value of link, bearer, or media setting
2698 * @cmd - which link, bearer, or media attribute to set (TIPC_CMD_SET_LINK_*)
2699 *
2700 * Caller must hold 'tipc_net_lock' to ensure link/bearer/media is not deleted.
2701 *
2702 * Returns 0 if value updated and negative value on error.
2703 */
2704static int link_cmd_set_value(const char *name, u32 new_value, u16 cmd)
2705{
2706 struct tipc_node *node;
2707 struct tipc_link *l_ptr;
2708 struct tipc_bearer *b_ptr;
2709 struct tipc_media *m_ptr;
2710
2711 l_ptr = link_find_link(name, &node);
2712 if (l_ptr) {
2713 /*
2714 * acquire node lock for tipc_link_send_proto_msg().
2715 * see "TIPC locking policy" in net.c.
2716 */
2717 tipc_node_lock(node);
2718 switch (cmd) {
2719 case TIPC_CMD_SET_LINK_TOL:
2720 link_set_supervision_props(l_ptr, new_value);
2721 tipc_link_send_proto_msg(l_ptr,
2722 STATE_MSG, 0, 0, new_value, 0, 0);
2723 break;
2724 case TIPC_CMD_SET_LINK_PRI:
2725 l_ptr->priority = new_value;
2726 tipc_link_send_proto_msg(l_ptr,
2727 STATE_MSG, 0, 0, 0, new_value, 0);
2728 break;
2729 case TIPC_CMD_SET_LINK_WINDOW:
2730 tipc_link_set_queue_limits(l_ptr, new_value);
2731 break;
2732 }
2733 tipc_node_unlock(node);
2734 return 0;
2735 }
2736
2737 b_ptr = tipc_bearer_find(name);
2738 if (b_ptr) {
2739 switch (cmd) {
2740 case TIPC_CMD_SET_LINK_TOL:
2741 b_ptr->tolerance = new_value;
2742 return 0;
2743 case TIPC_CMD_SET_LINK_PRI:
2744 b_ptr->priority = new_value;
2745 return 0;
2746 case TIPC_CMD_SET_LINK_WINDOW:
2747 b_ptr->window = new_value;
2748 return 0;
2749 }
2750 return -EINVAL;
2751 }
2752
2753 m_ptr = tipc_media_find(name);
2754 if (!m_ptr)
2755 return -ENODEV;
2756 switch (cmd) {
2757 case TIPC_CMD_SET_LINK_TOL:
2758 m_ptr->tolerance = new_value;
2759 return 0;
2760 case TIPC_CMD_SET_LINK_PRI:
2761 m_ptr->priority = new_value;
2762 return 0;
2763 case TIPC_CMD_SET_LINK_WINDOW:
2764 m_ptr->window = new_value;
2765 return 0;
2766 }
2767 return -EINVAL;
2768}
2769
2770struct sk_buff *tipc_link_cmd_config(const void *req_tlv_area, int req_tlv_space,
2771 u16 cmd)
2772{
2773 struct tipc_link_config *args;
2774 u32 new_value;
2775 int res;
2776
2777 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_CONFIG))
2778 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
2779
2780 args = (struct tipc_link_config *)TLV_DATA(req_tlv_area);
2781 new_value = ntohl(args->value);
2782
2783 if (!link_value_is_valid(cmd, new_value))
2784 return tipc_cfg_reply_error_string(
2785 "cannot change, value invalid");
2786
2787 if (!strcmp(args->name, tipc_bclink_name)) {
2788 if ((cmd == TIPC_CMD_SET_LINK_WINDOW) &&
2789 (tipc_bclink_set_queue_limits(new_value) == 0))
2790 return tipc_cfg_reply_none();
2791 return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED
2792 " (cannot change setting on broadcast link)");
2793 }
2794
2795 read_lock_bh(&tipc_net_lock);
2796 res = link_cmd_set_value(args->name, new_value, cmd);
2797 read_unlock_bh(&tipc_net_lock);
2798 if (res)
2799 return tipc_cfg_reply_error_string("cannot change link setting");
2800
2801 return tipc_cfg_reply_none();
2802}
2803
2804/**
2805 * link_reset_statistics - reset link statistics
2806 * @l_ptr: pointer to link
2807 */
2808static void link_reset_statistics(struct tipc_link *l_ptr)
2809{
2810 memset(&l_ptr->stats, 0, sizeof(l_ptr->stats));
2811 l_ptr->stats.sent_info = l_ptr->next_out_no;
2812 l_ptr->stats.recv_info = l_ptr->next_in_no;
2813}
2814
2815struct sk_buff *tipc_link_cmd_reset_stats(const void *req_tlv_area, int req_tlv_space)
2816{
2817 char *link_name;
2818 struct tipc_link *l_ptr;
2819 struct tipc_node *node;
2820
2821 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_NAME))
2822 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
2823
2824 link_name = (char *)TLV_DATA(req_tlv_area);
2825 if (!strcmp(link_name, tipc_bclink_name)) {
2826 if (tipc_bclink_reset_stats())
2827 return tipc_cfg_reply_error_string("link not found");
2828 return tipc_cfg_reply_none();
2829 }
2830
2831 read_lock_bh(&tipc_net_lock);
2832 l_ptr = link_find_link(link_name, &node);
2833 if (!l_ptr) {
2834 read_unlock_bh(&tipc_net_lock);
2835 return tipc_cfg_reply_error_string("link not found");
2836 }
2837
2838 tipc_node_lock(node);
2839 link_reset_statistics(l_ptr);
2840 tipc_node_unlock(node);
2841 read_unlock_bh(&tipc_net_lock);
2842 return tipc_cfg_reply_none();
2843}
2844
2845/**
2846 * percent - convert count to a percentage of total (rounding up or down)
2847 */
2848static u32 percent(u32 count, u32 total)
2849{
2850 return (count * 100 + (total / 2)) / total;
2851}
2852
2853/**
2854 * tipc_link_stats - print link statistics
2855 * @name: link name
2856 * @buf: print buffer area
2857 * @buf_size: size of print buffer area
2858 *
2859 * Returns length of print buffer data string (or 0 if error)
2860 */
2861static int tipc_link_stats(const char *name, char *buf, const u32 buf_size)
2862{
2863 struct print_buf pb;
2864 struct tipc_link *l_ptr;
2865 struct tipc_node *node;
2866 char *status;
2867 u32 profile_total = 0;
2868
2869 if (!strcmp(name, tipc_bclink_name))
2870 return tipc_bclink_stats(buf, buf_size);
2871
2872 tipc_printbuf_init(&pb, buf, buf_size);
2873
2874 read_lock_bh(&tipc_net_lock);
2875 l_ptr = link_find_link(name, &node);
2876 if (!l_ptr) {
2877 read_unlock_bh(&tipc_net_lock);
2878 return 0;
2879 }
2880 tipc_node_lock(node);
2881
2882 if (tipc_link_is_active(l_ptr))
2883 status = "ACTIVE";
2884 else if (tipc_link_is_up(l_ptr))
2885 status = "STANDBY";
2886 else
2887 status = "DEFUNCT";
2888 tipc_printf(&pb, "Link <%s>\n"
2889 " %s MTU:%u Priority:%u Tolerance:%u ms"
2890 " Window:%u packets\n",
2891 l_ptr->name, status, l_ptr->max_pkt,
2892 l_ptr->priority, l_ptr->tolerance, l_ptr->queue_limit[0]);
2893 tipc_printf(&pb, " RX packets:%u fragments:%u/%u bundles:%u/%u\n",
2894 l_ptr->next_in_no - l_ptr->stats.recv_info,
2895 l_ptr->stats.recv_fragments,
2896 l_ptr->stats.recv_fragmented,
2897 l_ptr->stats.recv_bundles,
2898 l_ptr->stats.recv_bundled);
2899 tipc_printf(&pb, " TX packets:%u fragments:%u/%u bundles:%u/%u\n",
2900 l_ptr->next_out_no - l_ptr->stats.sent_info,
2901 l_ptr->stats.sent_fragments,
2902 l_ptr->stats.sent_fragmented,
2903 l_ptr->stats.sent_bundles,
2904 l_ptr->stats.sent_bundled);
2905 profile_total = l_ptr->stats.msg_length_counts;
2906 if (!profile_total)
2907 profile_total = 1;
2908 tipc_printf(&pb, " TX profile sample:%u packets average:%u octets\n"
2909 " 0-64:%u%% -256:%u%% -1024:%u%% -4096:%u%% "
2910 "-16384:%u%% -32768:%u%% -66000:%u%%\n",
2911 l_ptr->stats.msg_length_counts,
2912 l_ptr->stats.msg_lengths_total / profile_total,
2913 percent(l_ptr->stats.msg_length_profile[0], profile_total),
2914 percent(l_ptr->stats.msg_length_profile[1], profile_total),
2915 percent(l_ptr->stats.msg_length_profile[2], profile_total),
2916 percent(l_ptr->stats.msg_length_profile[3], profile_total),
2917 percent(l_ptr->stats.msg_length_profile[4], profile_total),
2918 percent(l_ptr->stats.msg_length_profile[5], profile_total),
2919 percent(l_ptr->stats.msg_length_profile[6], profile_total));
2920 tipc_printf(&pb, " RX states:%u probes:%u naks:%u defs:%u dups:%u\n",
2921 l_ptr->stats.recv_states,
2922 l_ptr->stats.recv_probes,
2923 l_ptr->stats.recv_nacks,
2924 l_ptr->stats.deferred_recv,
2925 l_ptr->stats.duplicates);
2926 tipc_printf(&pb, " TX states:%u probes:%u naks:%u acks:%u dups:%u\n",
2927 l_ptr->stats.sent_states,
2928 l_ptr->stats.sent_probes,
2929 l_ptr->stats.sent_nacks,
2930 l_ptr->stats.sent_acks,
2931 l_ptr->stats.retransmitted);
2932 tipc_printf(&pb, " Congestion bearer:%u link:%u Send queue max:%u avg:%u\n",
2933 l_ptr->stats.bearer_congs,
2934 l_ptr->stats.link_congs,
2935 l_ptr->stats.max_queue_sz,
2936 l_ptr->stats.queue_sz_counts
2937 ? (l_ptr->stats.accu_queue_sz / l_ptr->stats.queue_sz_counts)
2938 : 0);
2939
2940 tipc_node_unlock(node);
2941 read_unlock_bh(&tipc_net_lock);
2942 return tipc_printbuf_validate(&pb);
2943}
2944
2945#define MAX_LINK_STATS_INFO 2000
2946
2947struct sk_buff *tipc_link_cmd_show_stats(const void *req_tlv_area, int req_tlv_space)
2948{
2949 struct sk_buff *buf;
2950 struct tlv_desc *rep_tlv;
2951 int str_len;
2952
2953 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_NAME))
2954 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
2955
2956 buf = tipc_cfg_reply_alloc(TLV_SPACE(MAX_LINK_STATS_INFO));
2957 if (!buf)
2958 return NULL;
2959
2960 rep_tlv = (struct tlv_desc *)buf->data;
2961
2962 str_len = tipc_link_stats((char *)TLV_DATA(req_tlv_area),
2963 (char *)TLV_DATA(rep_tlv), MAX_LINK_STATS_INFO);
2964 if (!str_len) {
2965 kfree_skb(buf);
2966 return tipc_cfg_reply_error_string("link not found");
2967 }
2968
2969 skb_put(buf, TLV_SPACE(str_len));
2970 TLV_SET(rep_tlv, TIPC_TLV_ULTRA_STRING, NULL, str_len);
2971
2972 return buf;
2973}
2974
2975/**
2976 * tipc_link_get_max_pkt - get maximum packet size to use when sending to destination
2977 * @dest: network address of destination node
2978 * @selector: used to select from set of active links
2979 *
2980 * If no active link can be found, uses default maximum packet size.
2981 */
2982u32 tipc_link_get_max_pkt(u32 dest, u32 selector)
2983{
2984 struct tipc_node *n_ptr;
2985 struct tipc_link *l_ptr;
2986 u32 res = MAX_PKT_DEFAULT;
2987
2988 if (dest == tipc_own_addr)
2989 return MAX_MSG_SIZE;
2990
2991 read_lock_bh(&tipc_net_lock);
2992 n_ptr = tipc_node_find(dest);
2993 if (n_ptr) {
2994 tipc_node_lock(n_ptr);
2995 l_ptr = n_ptr->active_links[selector & 1];
2996 if (l_ptr)
2997 res = l_ptr->max_pkt;
2998 tipc_node_unlock(n_ptr);
2999 }
3000 read_unlock_bh(&tipc_net_lock);
3001 return res;
3002}
3003
3004static void link_print(struct tipc_link *l_ptr, const char *str)
3005{
3006 char print_area[256];
3007 struct print_buf pb;
3008 struct print_buf *buf = &pb;
3009
3010 tipc_printbuf_init(buf, print_area, sizeof(print_area));
3011
3012 tipc_printf(buf, str);
3013 tipc_printf(buf, "Link %x<%s>:",
3014 l_ptr->addr, l_ptr->b_ptr->name);
3015
3016#ifdef CONFIG_TIPC_DEBUG
3017 if (link_reset_reset(l_ptr) || link_reset_unknown(l_ptr))
3018 goto print_state;
3019
3020 tipc_printf(buf, ": NXO(%u):", mod(l_ptr->next_out_no));
3021 tipc_printf(buf, "NXI(%u):", mod(l_ptr->next_in_no));
3022 tipc_printf(buf, "SQUE");
3023 if (l_ptr->first_out) {
3024 tipc_printf(buf, "[%u..", buf_seqno(l_ptr->first_out));
3025 if (l_ptr->next_out)
3026 tipc_printf(buf, "%u..", buf_seqno(l_ptr->next_out));
3027 tipc_printf(buf, "%u]", buf_seqno(l_ptr->last_out));
3028 if ((mod(buf_seqno(l_ptr->last_out) -
3029 buf_seqno(l_ptr->first_out))
3030 != (l_ptr->out_queue_size - 1)) ||
3031 (l_ptr->last_out->next != NULL)) {
3032 tipc_printf(buf, "\nSend queue inconsistency\n");
3033 tipc_printf(buf, "first_out= %p ", l_ptr->first_out);
3034 tipc_printf(buf, "next_out= %p ", l_ptr->next_out);
3035 tipc_printf(buf, "last_out= %p ", l_ptr->last_out);
3036 }
3037 } else
3038 tipc_printf(buf, "[]");
3039 tipc_printf(buf, "SQSIZ(%u)", l_ptr->out_queue_size);
3040 if (l_ptr->oldest_deferred_in) {
3041 u32 o = buf_seqno(l_ptr->oldest_deferred_in);
3042 u32 n = buf_seqno(l_ptr->newest_deferred_in);
3043 tipc_printf(buf, ":RQUE[%u..%u]", o, n);
3044 if (l_ptr->deferred_inqueue_sz != mod((n + 1) - o)) {
3045 tipc_printf(buf, ":RQSIZ(%u)",
3046 l_ptr->deferred_inqueue_sz);
3047 }
3048 }
3049print_state:
3050#endif
3051
3052 if (link_working_unknown(l_ptr))
3053 tipc_printf(buf, ":WU");
3054 else if (link_reset_reset(l_ptr))
3055 tipc_printf(buf, ":RR");
3056 else if (link_reset_unknown(l_ptr))
3057 tipc_printf(buf, ":RU");
3058 else if (link_working_working(l_ptr))
3059 tipc_printf(buf, ":WW");
3060 tipc_printf(buf, "\n");
3061
3062 tipc_printbuf_validate(buf);
3063 info("%s", print_area);
3064}