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staging: echo: Trivial indentation changes
[zen-stable.git] / net / tipc / link.c
blobebf338f7b14e7651b57e788fbac1a5057d6a135d
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
49 #define INVALID_SESSION 0x10000
50
51 /*
52 * Link state events:
53 */
54
55 #define STARTING_EVT 856384768 /* link processing trigger */
56 #define TRAFFIC_MSG_EVT 560815u /* rx'd ??? */
57 #define TIMEOUT_EVT 560817u /* link timer expired */
58
59 /*
60 * The following two 'message types' is really just implementation
61 * data conveniently stored in the message header.
62 * They must not be considered part of the protocol
63 */
64 #define OPEN_MSG 0
65 #define CLOSED_MSG 1
66
67 /*
68 * State value stored in 'exp_msg_count'
69 */
70
71 #define START_CHANGEOVER 100000u
72
73 /**
74 * struct link_name - deconstructed link name
75 * @addr_local: network address of node at this end
76 * @if_local: name of interface at this end
77 * @addr_peer: network address of node at far end
78 * @if_peer: name of interface at far end
79 */
80
81 struct link_name {
82 u32 addr_local;
83 char if_local[TIPC_MAX_IF_NAME];
84 u32 addr_peer;
85 char if_peer[TIPC_MAX_IF_NAME];
86 };
87
88 static void link_handle_out_of_seq_msg(struct link *l_ptr,
89 struct sk_buff *buf);
90 static void link_recv_proto_msg(struct link *l_ptr, struct sk_buff *buf);
91 static int link_recv_changeover_msg(struct link **l_ptr, struct sk_buff **buf);
92 static void link_set_supervision_props(struct link *l_ptr, u32 tolerance);
93 static int link_send_sections_long(struct tipc_port *sender,
94 struct iovec const *msg_sect,
95 u32 num_sect, u32 destnode);
96 static void link_check_defragm_bufs(struct link *l_ptr);
97 static void link_state_event(struct link *l_ptr, u32 event);
98 static void link_reset_statistics(struct link *l_ptr);
99 static void link_print(struct link *l_ptr, const char *str);
100 static void link_start(struct link *l_ptr);
101 static int link_send_long_buf(struct link *l_ptr, struct sk_buff *buf);
102
103 /*
104 * Simple link routines
105 */
106
107 static unsigned int align(unsigned int i)
108 {
109 return (i + 3) & ~3u;
110 }
111
112 static void link_init_max_pkt(struct link *l_ptr)
113 {
114 u32 max_pkt;
115
116 max_pkt = (l_ptr->b_ptr->mtu & ~3);
117 if (max_pkt > MAX_MSG_SIZE)
118 max_pkt = MAX_MSG_SIZE;
119
120 l_ptr->max_pkt_target = max_pkt;
121 if (l_ptr->max_pkt_target < MAX_PKT_DEFAULT)
122 l_ptr->max_pkt = l_ptr->max_pkt_target;
123 else
124 l_ptr->max_pkt = MAX_PKT_DEFAULT;
125
126 l_ptr->max_pkt_probes = 0;
127 }
128
129 static u32 link_next_sent(struct link *l_ptr)
130 {
131 if (l_ptr->next_out)
132 return msg_seqno(buf_msg(l_ptr->next_out));
133 return mod(l_ptr->next_out_no);
134 }
135
136 static u32 link_last_sent(struct link *l_ptr)
137 {
138 return mod(link_next_sent(l_ptr) - 1);
139 }
140
141 /*
142 * Simple non-static link routines (i.e. referenced outside this file)
143 */
144
145 int tipc_link_is_up(struct link *l_ptr)
146 {
147 if (!l_ptr)
148 return 0;
149 return link_working_working(l_ptr) || link_working_unknown(l_ptr);
150 }
151
152 int tipc_link_is_active(struct link *l_ptr)
153 {
154 return (l_ptr->owner->active_links[0] == l_ptr) ||
155 (l_ptr->owner->active_links[1] == l_ptr);
156 }
157
158 /**
159 * link_name_validate - validate & (optionally) deconstruct link name
160 * @name - ptr to link name string
161 * @name_parts - ptr to area for link name components (or NULL if not needed)
162 *
163 * Returns 1 if link name is valid, otherwise 0.
164 */
165
166 static int link_name_validate(const char *name, struct link_name *name_parts)
167 {
168 char name_copy[TIPC_MAX_LINK_NAME];
169 char *addr_local;
170 char *if_local;
171 char *addr_peer;
172 char *if_peer;
173 char dummy;
174 u32 z_local, c_local, n_local;
175 u32 z_peer, c_peer, n_peer;
176 u32 if_local_len;
177 u32 if_peer_len;
178
179 /* copy link name & ensure length is OK */
180
181 name_copy[TIPC_MAX_LINK_NAME - 1] = 0;
182 /* need above in case non-Posix strncpy() doesn't pad with nulls */
183 strncpy(name_copy, name, TIPC_MAX_LINK_NAME);
184 if (name_copy[TIPC_MAX_LINK_NAME - 1] != 0)
185 return 0;
186
187 /* ensure all component parts of link name are present */
188
189 addr_local = name_copy;
190 if_local = strchr(addr_local, ':');
191 if (if_local == NULL)
192 return 0;
193 *(if_local++) = 0;
194 addr_peer = strchr(if_local, '-');
195 if (addr_peer == NULL)
196 return 0;
197 *(addr_peer++) = 0;
198 if_local_len = addr_peer - if_local;
199 if_peer = strchr(addr_peer, ':');
200 if (if_peer == NULL)
201 return 0;
202 *(if_peer++) = 0;
203 if_peer_len = strlen(if_peer) + 1;
204
205 /* validate component parts of link name */
206
207 if ((sscanf(addr_local, "%u.%u.%u%c",
208 &z_local, &c_local, &n_local, &dummy) != 3) ||
209 (sscanf(addr_peer, "%u.%u.%u%c",
210 &z_peer, &c_peer, &n_peer, &dummy) != 3) ||
211 (z_local > 255) || (c_local > 4095) || (n_local > 4095) ||
212 (z_peer > 255) || (c_peer > 4095) || (n_peer > 4095) ||
213 (if_local_len <= 1) || (if_local_len > TIPC_MAX_IF_NAME) ||
214 (if_peer_len <= 1) || (if_peer_len > TIPC_MAX_IF_NAME) ||
215 (strspn(if_local, tipc_alphabet) != (if_local_len - 1)) ||
216 (strspn(if_peer, tipc_alphabet) != (if_peer_len - 1)))
217 return 0;
218
219 /* return link name components, if necessary */
220
221 if (name_parts) {
222 name_parts->addr_local = tipc_addr(z_local, c_local, n_local);
223 strcpy(name_parts->if_local, if_local);
224 name_parts->addr_peer = tipc_addr(z_peer, c_peer, n_peer);
225 strcpy(name_parts->if_peer, if_peer);
226 }
227 return 1;
228 }
229
230 /**
231 * link_timeout - handle expiration of link timer
232 * @l_ptr: pointer to link
233 *
234 * This routine must not grab "tipc_net_lock" to avoid a potential deadlock conflict
235 * with tipc_link_delete(). (There is no risk that the node will be deleted by
236 * another thread because tipc_link_delete() always cancels the link timer before
237 * tipc_node_delete() is called.)
238 */
239
240 static void link_timeout(struct link *l_ptr)
241 {
242 tipc_node_lock(l_ptr->owner);
243
244 /* update counters used in statistical profiling of send traffic */
245
246 l_ptr->stats.accu_queue_sz += l_ptr->out_queue_size;
247 l_ptr->stats.queue_sz_counts++;
248
249 if (l_ptr->first_out) {
250 struct tipc_msg *msg = buf_msg(l_ptr->first_out);
251 u32 length = msg_size(msg);
252
253 if ((msg_user(msg) == MSG_FRAGMENTER) &&
254 (msg_type(msg) == FIRST_FRAGMENT)) {
255 length = msg_size(msg_get_wrapped(msg));
256 }
257 if (length) {
258 l_ptr->stats.msg_lengths_total += length;
259 l_ptr->stats.msg_length_counts++;
260 if (length <= 64)
261 l_ptr->stats.msg_length_profile[0]++;
262 else if (length <= 256)
263 l_ptr->stats.msg_length_profile[1]++;
264 else if (length <= 1024)
265 l_ptr->stats.msg_length_profile[2]++;
266 else if (length <= 4096)
267 l_ptr->stats.msg_length_profile[3]++;
268 else if (length <= 16384)
269 l_ptr->stats.msg_length_profile[4]++;
270 else if (length <= 32768)
271 l_ptr->stats.msg_length_profile[5]++;
272 else
273 l_ptr->stats.msg_length_profile[6]++;
274 }
275 }
276
277 /* do all other link processing performed on a periodic basis */
278
279 link_check_defragm_bufs(l_ptr);
280
281 link_state_event(l_ptr, TIMEOUT_EVT);
282
283 if (l_ptr->next_out)
284 tipc_link_push_queue(l_ptr);
285
286 tipc_node_unlock(l_ptr->owner);
287 }
288
289 static void link_set_timer(struct link *l_ptr, u32 time)
290 {
291 k_start_timer(&l_ptr->timer, time);
292 }
293
294 /**
295 * tipc_link_create - create a new link
296 * @n_ptr: pointer to associated node
297 * @b_ptr: pointer to associated bearer
298 * @media_addr: media address to use when sending messages over link
299 *
300 * Returns pointer to link.
301 */
302
303 struct link *tipc_link_create(struct tipc_node *n_ptr,
304 struct tipc_bearer *b_ptr,
305 const struct tipc_media_addr *media_addr)
306 {
307 struct link *l_ptr;
308 struct tipc_msg *msg;
309 char *if_name;
310 char addr_string[16];
311 u32 peer = n_ptr->addr;
312
313 if (n_ptr->link_cnt >= 2) {
314 tipc_addr_string_fill(addr_string, n_ptr->addr);
315 err("Attempt to establish third link to %s\n", addr_string);
316 return NULL;
317 }
318
319 if (n_ptr->links[b_ptr->identity]) {
320 tipc_addr_string_fill(addr_string, n_ptr->addr);
321 err("Attempt to establish second link on <%s> to %s\n",
322 b_ptr->name, addr_string);
323 return NULL;
324 }
325
326 l_ptr = kzalloc(sizeof(*l_ptr), GFP_ATOMIC);
327 if (!l_ptr) {
328 warn("Link creation failed, no memory\n");
329 return NULL;
330 }
331
332 l_ptr->addr = peer;
333 if_name = strchr(b_ptr->name, ':') + 1;
334 sprintf(l_ptr->name, "%u.%u.%u:%s-%u.%u.%u:",
335 tipc_zone(tipc_own_addr), tipc_cluster(tipc_own_addr),
336 tipc_node(tipc_own_addr),
337 if_name,
338 tipc_zone(peer), tipc_cluster(peer), tipc_node(peer));
339 /* note: peer i/f is appended to link name by reset/activate */
340 memcpy(&l_ptr->media_addr, media_addr, sizeof(*media_addr));
341 l_ptr->owner = n_ptr;
342 l_ptr->checkpoint = 1;
343 l_ptr->b_ptr = b_ptr;
344 link_set_supervision_props(l_ptr, b_ptr->media->tolerance);
345 l_ptr->state = RESET_UNKNOWN;
346
347 l_ptr->pmsg = (struct tipc_msg *)&l_ptr->proto_msg;
348 msg = l_ptr->pmsg;
349 tipc_msg_init(msg, LINK_PROTOCOL, RESET_MSG, INT_H_SIZE, l_ptr->addr);
350 msg_set_size(msg, sizeof(l_ptr->proto_msg));
351 msg_set_session(msg, (tipc_random & 0xffff));
352 msg_set_bearer_id(msg, b_ptr->identity);
353 strcpy((char *)msg_data(msg), if_name);
354
355 l_ptr->priority = b_ptr->priority;
356 tipc_link_set_queue_limits(l_ptr, b_ptr->media->window);
357
358 link_init_max_pkt(l_ptr);
359
360 l_ptr->next_out_no = 1;
361 INIT_LIST_HEAD(&l_ptr->waiting_ports);
362
363 link_reset_statistics(l_ptr);
364
365 tipc_node_attach_link(n_ptr, l_ptr);
366
367 k_init_timer(&l_ptr->timer, (Handler)link_timeout, (unsigned long)l_ptr);
368 list_add_tail(&l_ptr->link_list, &b_ptr->links);
369 tipc_k_signal((Handler)link_start, (unsigned long)l_ptr);
370
371 return l_ptr;
372 }
373
374 /**
375 * tipc_link_delete - delete a link
376 * @l_ptr: pointer to link
377 *
378 * Note: 'tipc_net_lock' is write_locked, bearer is locked.
379 * This routine must not grab the node lock until after link timer cancellation
380 * to avoid a potential deadlock situation.
381 */
382
383 void tipc_link_delete(struct link *l_ptr)
384 {
385 if (!l_ptr) {
386 err("Attempt to delete non-existent link\n");
387 return;
388 }
389
390 k_cancel_timer(&l_ptr->timer);
391
392 tipc_node_lock(l_ptr->owner);
393 tipc_link_reset(l_ptr);
394 tipc_node_detach_link(l_ptr->owner, l_ptr);
395 tipc_link_stop(l_ptr);
396 list_del_init(&l_ptr->link_list);
397 tipc_node_unlock(l_ptr->owner);
398 k_term_timer(&l_ptr->timer);
399 kfree(l_ptr);
400 }
401
402 static void link_start(struct link *l_ptr)
403 {
404 tipc_node_lock(l_ptr->owner);
405 link_state_event(l_ptr, STARTING_EVT);
406 tipc_node_unlock(l_ptr->owner);
407 }
408
409 /**
410 * link_schedule_port - schedule port for deferred sending
411 * @l_ptr: pointer to link
412 * @origport: reference to sending port
413 * @sz: amount of data to be sent
414 *
415 * Schedules port for renewed sending of messages after link congestion
416 * has abated.
417 */
418
419 static int link_schedule_port(struct link *l_ptr, u32 origport, u32 sz)
420 {
421 struct tipc_port *p_ptr;
422
423 spin_lock_bh(&tipc_port_list_lock);
424 p_ptr = tipc_port_lock(origport);
425 if (p_ptr) {
426 if (!p_ptr->wakeup)
427 goto exit;
428 if (!list_empty(&p_ptr->wait_list))
429 goto exit;
430 p_ptr->congested = 1;
431 p_ptr->waiting_pkts = 1 + ((sz - 1) / l_ptr->max_pkt);
432 list_add_tail(&p_ptr->wait_list, &l_ptr->waiting_ports);
433 l_ptr->stats.link_congs++;
434 exit:
435 tipc_port_unlock(p_ptr);
436 }
437 spin_unlock_bh(&tipc_port_list_lock);
438 return -ELINKCONG;
439 }
440
441 void tipc_link_wakeup_ports(struct link *l_ptr, int all)
442 {
443 struct tipc_port *p_ptr;
444 struct tipc_port *temp_p_ptr;
445 int win = l_ptr->queue_limit[0] - l_ptr->out_queue_size;
446
447 if (all)
448 win = 100000;
449 if (win <= 0)
450 return;
451 if (!spin_trylock_bh(&tipc_port_list_lock))
452 return;
453 if (link_congested(l_ptr))
454 goto exit;
455 list_for_each_entry_safe(p_ptr, temp_p_ptr, &l_ptr->waiting_ports,
456 wait_list) {
457 if (win <= 0)
458 break;
459 list_del_init(&p_ptr->wait_list);
460 spin_lock_bh(p_ptr->lock);
461 p_ptr->congested = 0;
462 p_ptr->wakeup(p_ptr);
463 win -= p_ptr->waiting_pkts;
464 spin_unlock_bh(p_ptr->lock);
465 }
466
467 exit:
468 spin_unlock_bh(&tipc_port_list_lock);
469 }
470
471 /**
472 * link_release_outqueue - purge link's outbound message queue
473 * @l_ptr: pointer to link
474 */
475
476 static void link_release_outqueue(struct link *l_ptr)
477 {
478 struct sk_buff *buf = l_ptr->first_out;
479 struct sk_buff *next;
480
481 while (buf) {
482 next = buf->next;
483 buf_discard(buf);
484 buf = next;
485 }
486 l_ptr->first_out = NULL;
487 l_ptr->out_queue_size = 0;
488 }
489
490 /**
491 * tipc_link_reset_fragments - purge link's inbound message fragments queue
492 * @l_ptr: pointer to link
493 */
494
495 void tipc_link_reset_fragments(struct link *l_ptr)
496 {
497 struct sk_buff *buf = l_ptr->defragm_buf;
498 struct sk_buff *next;
499
500 while (buf) {
501 next = buf->next;
502 buf_discard(buf);
503 buf = next;
504 }
505 l_ptr->defragm_buf = NULL;
506 }
507
508 /**
509 * tipc_link_stop - purge all inbound and outbound messages associated with link
510 * @l_ptr: pointer to link
511 */
512
513 void tipc_link_stop(struct link *l_ptr)
514 {
515 struct sk_buff *buf;
516 struct sk_buff *next;
517
518 buf = l_ptr->oldest_deferred_in;
519 while (buf) {
520 next = buf->next;
521 buf_discard(buf);
522 buf = next;
523 }
524
525 buf = l_ptr->first_out;
526 while (buf) {
527 next = buf->next;
528 buf_discard(buf);
529 buf = next;
530 }
531
532 tipc_link_reset_fragments(l_ptr);
533
534 buf_discard(l_ptr->proto_msg_queue);
535 l_ptr->proto_msg_queue = NULL;
536 }
537
538 /* LINK EVENT CODE IS NOT SUPPORTED AT PRESENT */
539 #define link_send_event(fcn, l_ptr, up) do { } while (0)
540
541 void tipc_link_reset(struct link *l_ptr)
542 {
543 struct sk_buff *buf;
544 u32 prev_state = l_ptr->state;
545 u32 checkpoint = l_ptr->next_in_no;
546 int was_active_link = tipc_link_is_active(l_ptr);
547
548 msg_set_session(l_ptr->pmsg, ((msg_session(l_ptr->pmsg) + 1) & 0xffff));
549
550 /* Link is down, accept any session */
551 l_ptr->peer_session = INVALID_SESSION;
552
553 /* Prepare for max packet size negotiation */
554 link_init_max_pkt(l_ptr);
555
556 l_ptr->state = RESET_UNKNOWN;
557
558 if ((prev_state == RESET_UNKNOWN) || (prev_state == RESET_RESET))
559 return;
560
561 tipc_node_link_down(l_ptr->owner, l_ptr);
562 tipc_bearer_remove_dest(l_ptr->b_ptr, l_ptr->addr);
563
564 if (was_active_link && tipc_node_active_links(l_ptr->owner) &&
565 l_ptr->owner->permit_changeover) {
566 l_ptr->reset_checkpoint = checkpoint;
567 l_ptr->exp_msg_count = START_CHANGEOVER;
568 }
569
570 /* Clean up all queues: */
571
572 link_release_outqueue(l_ptr);
573 buf_discard(l_ptr->proto_msg_queue);
574 l_ptr->proto_msg_queue = NULL;
575 buf = l_ptr->oldest_deferred_in;
576 while (buf) {
577 struct sk_buff *next = buf->next;
578 buf_discard(buf);
579 buf = next;
580 }
581 if (!list_empty(&l_ptr->waiting_ports))
582 tipc_link_wakeup_ports(l_ptr, 1);
583
584 l_ptr->retransm_queue_head = 0;
585 l_ptr->retransm_queue_size = 0;
586 l_ptr->last_out = NULL;
587 l_ptr->first_out = NULL;
588 l_ptr->next_out = NULL;
589 l_ptr->unacked_window = 0;
590 l_ptr->checkpoint = 1;
591 l_ptr->next_out_no = 1;
592 l_ptr->deferred_inqueue_sz = 0;
593 l_ptr->oldest_deferred_in = NULL;
594 l_ptr->newest_deferred_in = NULL;
595 l_ptr->fsm_msg_cnt = 0;
596 l_ptr->stale_count = 0;
597 link_reset_statistics(l_ptr);
598
599 link_send_event(tipc_cfg_link_event, l_ptr, 0);
600 if (!in_own_cluster(l_ptr->addr))
601 link_send_event(tipc_disc_link_event, l_ptr, 0);
602 }
603
604
605 static void link_activate(struct link *l_ptr)
606 {
607 l_ptr->next_in_no = l_ptr->stats.recv_info = 1;
608 tipc_node_link_up(l_ptr->owner, l_ptr);
609 tipc_bearer_add_dest(l_ptr->b_ptr, l_ptr->addr);
610 link_send_event(tipc_cfg_link_event, l_ptr, 1);
611 if (!in_own_cluster(l_ptr->addr))
612 link_send_event(tipc_disc_link_event, l_ptr, 1);
613 }
614
615 /**
616 * link_state_event - link finite state machine
617 * @l_ptr: pointer to link
618 * @event: state machine event to process
619 */
620
621 static void link_state_event(struct link *l_ptr, unsigned event)
622 {
623 struct link *other;
624 u32 cont_intv = l_ptr->continuity_interval;
625
626 if (!l_ptr->started && (event != STARTING_EVT))
627 return; /* Not yet. */
628
629 if (link_blocked(l_ptr)) {
630 if (event == TIMEOUT_EVT)
631 link_set_timer(l_ptr, cont_intv);
632 return; /* Changeover going on */
633 }
634
635 switch (l_ptr->state) {
636 case WORKING_WORKING:
637 switch (event) {
638 case TRAFFIC_MSG_EVT:
639 case ACTIVATE_MSG:
640 break;
641 case TIMEOUT_EVT:
642 if (l_ptr->next_in_no != l_ptr->checkpoint) {
643 l_ptr->checkpoint = l_ptr->next_in_no;
644 if (tipc_bclink_acks_missing(l_ptr->owner)) {
645 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
646 0, 0, 0, 0, 0);
647 l_ptr->fsm_msg_cnt++;
648 } else if (l_ptr->max_pkt < l_ptr->max_pkt_target) {
649 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
650 1, 0, 0, 0, 0);
651 l_ptr->fsm_msg_cnt++;
652 }
653 link_set_timer(l_ptr, cont_intv);
654 break;
655 }
656 l_ptr->state = WORKING_UNKNOWN;
657 l_ptr->fsm_msg_cnt = 0;
658 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
659 l_ptr->fsm_msg_cnt++;
660 link_set_timer(l_ptr, cont_intv / 4);
661 break;
662 case RESET_MSG:
663 info("Resetting link <%s>, requested by peer\n",
664 l_ptr->name);
665 tipc_link_reset(l_ptr);
666 l_ptr->state = RESET_RESET;
667 l_ptr->fsm_msg_cnt = 0;
668 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0);
669 l_ptr->fsm_msg_cnt++;
670 link_set_timer(l_ptr, cont_intv);
671 break;
672 default:
673 err("Unknown link event %u in WW state\n", event);
674 }
675 break;
676 case WORKING_UNKNOWN:
677 switch (event) {
678 case TRAFFIC_MSG_EVT:
679 case ACTIVATE_MSG:
680 l_ptr->state = WORKING_WORKING;
681 l_ptr->fsm_msg_cnt = 0;
682 link_set_timer(l_ptr, cont_intv);
683 break;
684 case RESET_MSG:
685 info("Resetting link <%s>, requested by peer "
686 "while probing\n", l_ptr->name);
687 tipc_link_reset(l_ptr);
688 l_ptr->state = RESET_RESET;
689 l_ptr->fsm_msg_cnt = 0;
690 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0);
691 l_ptr->fsm_msg_cnt++;
692 link_set_timer(l_ptr, cont_intv);
693 break;
694 case TIMEOUT_EVT:
695 if (l_ptr->next_in_no != l_ptr->checkpoint) {
696 l_ptr->state = WORKING_WORKING;
697 l_ptr->fsm_msg_cnt = 0;
698 l_ptr->checkpoint = l_ptr->next_in_no;
699 if (tipc_bclink_acks_missing(l_ptr->owner)) {
700 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
701 0, 0, 0, 0, 0);
702 l_ptr->fsm_msg_cnt++;
703 }
704 link_set_timer(l_ptr, cont_intv);
705 } else if (l_ptr->fsm_msg_cnt < l_ptr->abort_limit) {
706 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
707 1, 0, 0, 0, 0);
708 l_ptr->fsm_msg_cnt++;
709 link_set_timer(l_ptr, cont_intv / 4);
710 } else { /* Link has failed */
711 warn("Resetting link <%s>, peer not responding\n",
712 l_ptr->name);
713 tipc_link_reset(l_ptr);
714 l_ptr->state = RESET_UNKNOWN;
715 l_ptr->fsm_msg_cnt = 0;
716 tipc_link_send_proto_msg(l_ptr, RESET_MSG,
717 0, 0, 0, 0, 0);
718 l_ptr->fsm_msg_cnt++;
719 link_set_timer(l_ptr, cont_intv);
720 }
721 break;
722 default:
723 err("Unknown link event %u in WU state\n", event);
724 }
725 break;
726 case RESET_UNKNOWN:
727 switch (event) {
728 case TRAFFIC_MSG_EVT:
729 break;
730 case ACTIVATE_MSG:
731 other = l_ptr->owner->active_links[0];
732 if (other && link_working_unknown(other))
733 break;
734 l_ptr->state = WORKING_WORKING;
735 l_ptr->fsm_msg_cnt = 0;
736 link_activate(l_ptr);
737 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
738 l_ptr->fsm_msg_cnt++;
739 link_set_timer(l_ptr, cont_intv);
740 break;
741 case RESET_MSG:
742 l_ptr->state = RESET_RESET;
743 l_ptr->fsm_msg_cnt = 0;
744 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 1, 0, 0, 0, 0);
745 l_ptr->fsm_msg_cnt++;
746 link_set_timer(l_ptr, cont_intv);
747 break;
748 case STARTING_EVT:
749 l_ptr->started = 1;
750 /* fall through */
751 case TIMEOUT_EVT:
752 tipc_link_send_proto_msg(l_ptr, RESET_MSG, 0, 0, 0, 0, 0);
753 l_ptr->fsm_msg_cnt++;
754 link_set_timer(l_ptr, cont_intv);
755 break;
756 default:
757 err("Unknown link event %u in RU state\n", event);
758 }
759 break;
760 case RESET_RESET:
761 switch (event) {
762 case TRAFFIC_MSG_EVT:
763 case ACTIVATE_MSG:
764 other = l_ptr->owner->active_links[0];
765 if (other && link_working_unknown(other))
766 break;
767 l_ptr->state = WORKING_WORKING;
768 l_ptr->fsm_msg_cnt = 0;
769 link_activate(l_ptr);
770 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
771 l_ptr->fsm_msg_cnt++;
772 link_set_timer(l_ptr, cont_intv);
773 break;
774 case RESET_MSG:
775 break;
776 case TIMEOUT_EVT:
777 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0);
778 l_ptr->fsm_msg_cnt++;
779 link_set_timer(l_ptr, cont_intv);
780 break;
781 default:
782 err("Unknown link event %u in RR state\n", event);
783 }
784 break;
785 default:
786 err("Unknown link state %u/%u\n", l_ptr->state, event);
787 }
788 }
789
790 /*
791 * link_bundle_buf(): Append contents of a buffer to
792 * the tail of an existing one.
793 */
794
795 static int link_bundle_buf(struct link *l_ptr,
796 struct sk_buff *bundler,
797 struct sk_buff *buf)
798 {
799 struct tipc_msg *bundler_msg = buf_msg(bundler);
800 struct tipc_msg *msg = buf_msg(buf);
801 u32 size = msg_size(msg);
802 u32 bundle_size = msg_size(bundler_msg);
803 u32 to_pos = align(bundle_size);
804 u32 pad = to_pos - bundle_size;
805
806 if (msg_user(bundler_msg) != MSG_BUNDLER)
807 return 0;
808 if (msg_type(bundler_msg) != OPEN_MSG)
809 return 0;
810 if (skb_tailroom(bundler) < (pad + size))
811 return 0;
812 if (l_ptr->max_pkt < (to_pos + size))
813 return 0;
814
815 skb_put(bundler, pad + size);
816 skb_copy_to_linear_data_offset(bundler, to_pos, buf->data, size);
817 msg_set_size(bundler_msg, to_pos + size);
818 msg_set_msgcnt(bundler_msg, msg_msgcnt(bundler_msg) + 1);
819 buf_discard(buf);
820 l_ptr->stats.sent_bundled++;
821 return 1;
822 }
823
824 static void link_add_to_outqueue(struct link *l_ptr,
825 struct sk_buff *buf,
826 struct tipc_msg *msg)
827 {
828 u32 ack = mod(l_ptr->next_in_no - 1);
829 u32 seqno = mod(l_ptr->next_out_no++);
830
831 msg_set_word(msg, 2, ((ack << 16) | seqno));
832 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
833 buf->next = NULL;
834 if (l_ptr->first_out) {
835 l_ptr->last_out->next = buf;
836 l_ptr->last_out = buf;
837 } else
838 l_ptr->first_out = l_ptr->last_out = buf;
839
840 l_ptr->out_queue_size++;
841 if (l_ptr->out_queue_size > l_ptr->stats.max_queue_sz)
842 l_ptr->stats.max_queue_sz = l_ptr->out_queue_size;
843 }
844
845 /*
846 * tipc_link_send_buf() is the 'full path' for messages, called from
847 * inside TIPC when the 'fast path' in tipc_send_buf
848 * has failed, and from link_send()
849 */
850
851 int tipc_link_send_buf(struct link *l_ptr, struct sk_buff *buf)
852 {
853 struct tipc_msg *msg = buf_msg(buf);
854 u32 size = msg_size(msg);
855 u32 dsz = msg_data_sz(msg);
856 u32 queue_size = l_ptr->out_queue_size;
857 u32 imp = tipc_msg_tot_importance(msg);
858 u32 queue_limit = l_ptr->queue_limit[imp];
859 u32 max_packet = l_ptr->max_pkt;
860
861 msg_set_prevnode(msg, tipc_own_addr); /* If routed message */
862
863 /* Match msg importance against queue limits: */
864
865 if (unlikely(queue_size >= queue_limit)) {
866 if (imp <= TIPC_CRITICAL_IMPORTANCE) {
867 return link_schedule_port(l_ptr, msg_origport(msg),
868 size);
869 }
870 buf_discard(buf);
871 if (imp > CONN_MANAGER) {
872 warn("Resetting link <%s>, send queue full", l_ptr->name);
873 tipc_link_reset(l_ptr);
874 }
875 return dsz;
876 }
877
878 /* Fragmentation needed ? */
879
880 if (size > max_packet)
881 return link_send_long_buf(l_ptr, buf);
882
883 /* Packet can be queued or sent: */
884
885 if (likely(!tipc_bearer_congested(l_ptr->b_ptr, l_ptr) &&
886 !link_congested(l_ptr))) {
887 link_add_to_outqueue(l_ptr, buf, msg);
888
889 if (likely(tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr))) {
890 l_ptr->unacked_window = 0;
891 } else {
892 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr);
893 l_ptr->stats.bearer_congs++;
894 l_ptr->next_out = buf;
895 }
896 return dsz;
897 }
898 /* Congestion: can message be bundled ?: */
899
900 if ((msg_user(msg) != CHANGEOVER_PROTOCOL) &&
901 (msg_user(msg) != MSG_FRAGMENTER)) {
902
903 /* Try adding message to an existing bundle */
904
905 if (l_ptr->next_out &&
906 link_bundle_buf(l_ptr, l_ptr->last_out, buf)) {
907 tipc_bearer_resolve_congestion(l_ptr->b_ptr, l_ptr);
908 return dsz;
909 }
910
911 /* Try creating a new bundle */
912
913 if (size <= max_packet * 2 / 3) {
914 struct sk_buff *bundler = tipc_buf_acquire(max_packet);
915 struct tipc_msg bundler_hdr;
916
917 if (bundler) {
918 tipc_msg_init(&bundler_hdr, MSG_BUNDLER, OPEN_MSG,
919 INT_H_SIZE, l_ptr->addr);
920 skb_copy_to_linear_data(bundler, &bundler_hdr,
921 INT_H_SIZE);
922 skb_trim(bundler, INT_H_SIZE);
923 link_bundle_buf(l_ptr, bundler, buf);
924 buf = bundler;
925 msg = buf_msg(buf);
926 l_ptr->stats.sent_bundles++;
927 }
928 }
929 }
930 if (!l_ptr->next_out)
931 l_ptr->next_out = buf;
932 link_add_to_outqueue(l_ptr, buf, msg);
933 tipc_bearer_resolve_congestion(l_ptr->b_ptr, l_ptr);
934 return dsz;
935 }
936
937 /*
938 * tipc_link_send(): same as tipc_link_send_buf(), but the link to use has
939 * not been selected yet, and the the owner node is not locked
940 * Called by TIPC internal users, e.g. the name distributor
941 */
942
943 int tipc_link_send(struct sk_buff *buf, u32 dest, u32 selector)
944 {
945 struct link *l_ptr;
946 struct tipc_node *n_ptr;
947 int res = -ELINKCONG;
948
949 read_lock_bh(&tipc_net_lock);
950 n_ptr = tipc_node_find(dest);
951 if (n_ptr) {
952 tipc_node_lock(n_ptr);
953 l_ptr = n_ptr->active_links[selector & 1];
954 if (l_ptr)
955 res = tipc_link_send_buf(l_ptr, buf);
956 else
957 buf_discard(buf);
958 tipc_node_unlock(n_ptr);
959 } else {
960 buf_discard(buf);
961 }
962 read_unlock_bh(&tipc_net_lock);
963 return res;
964 }
965
966 /*
967 * link_send_buf_fast: Entry for data messages where the
968 * destination link is known and the header is complete,
969 * inclusive total message length. Very time critical.
970 * Link is locked. Returns user data length.
971 */
972
973 static int link_send_buf_fast(struct link *l_ptr, struct sk_buff *buf,
974 u32 *used_max_pkt)
975 {
976 struct tipc_msg *msg = buf_msg(buf);
977 int res = msg_data_sz(msg);
978
979 if (likely(!link_congested(l_ptr))) {
980 if (likely(msg_size(msg) <= l_ptr->max_pkt)) {
981 if (likely(list_empty(&l_ptr->b_ptr->cong_links))) {
982 link_add_to_outqueue(l_ptr, buf, msg);
983 if (likely(tipc_bearer_send(l_ptr->b_ptr, buf,
984 &l_ptr->media_addr))) {
985 l_ptr->unacked_window = 0;
986 return res;
987 }
988 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr);
989 l_ptr->stats.bearer_congs++;
990 l_ptr->next_out = buf;
991 return res;
992 }
993 } else
994 *used_max_pkt = l_ptr->max_pkt;
995 }
996 return tipc_link_send_buf(l_ptr, buf); /* All other cases */
997 }
998
999 /*
1000 * tipc_send_buf_fast: Entry for data messages where the
1001 * destination node is known and the header is complete,
1002 * inclusive total message length.
1003 * Returns user data length.
1004 */
1005 int tipc_send_buf_fast(struct sk_buff *buf, u32 destnode)
1006 {
1007 struct link *l_ptr;
1008 struct tipc_node *n_ptr;
1009 int res;
1010 u32 selector = msg_origport(buf_msg(buf)) & 1;
1011 u32 dummy;
1012
1013 if (destnode == tipc_own_addr)
1014 return tipc_port_recv_msg(buf);
1015
1016 read_lock_bh(&tipc_net_lock);
1017 n_ptr = tipc_node_find(destnode);
1018 if (likely(n_ptr)) {
1019 tipc_node_lock(n_ptr);
1020 l_ptr = n_ptr->active_links[selector];
1021 if (likely(l_ptr)) {
1022 res = link_send_buf_fast(l_ptr, buf, &dummy);
1023 tipc_node_unlock(n_ptr);
1024 read_unlock_bh(&tipc_net_lock);
1025 return res;
1026 }
1027 tipc_node_unlock(n_ptr);
1028 }
1029 read_unlock_bh(&tipc_net_lock);
1030 res = msg_data_sz(buf_msg(buf));
1031 tipc_reject_msg(buf, TIPC_ERR_NO_NODE);
1032 return res;
1033 }
1034
1035
1036 /*
1037 * tipc_link_send_sections_fast: Entry for messages where the
1038 * destination processor is known and the header is complete,
1039 * except for total message length.
1040 * Returns user data length or errno.
1041 */
1042 int tipc_link_send_sections_fast(struct tipc_port *sender,
1043 struct iovec const *msg_sect,
1044 const u32 num_sect,
1045 u32 destaddr)
1046 {
1047 struct tipc_msg *hdr = &sender->phdr;
1048 struct link *l_ptr;
1049 struct sk_buff *buf;
1050 struct tipc_node *node;
1051 int res;
1052 u32 selector = msg_origport(hdr) & 1;
1053
1054 again:
1055 /*
1056 * Try building message using port's max_pkt hint.
1057 * (Must not hold any locks while building message.)
1058 */
1059
1060 res = tipc_msg_build(hdr, msg_sect, num_sect, sender->max_pkt,
1061 !sender->user_port, &buf);
1062
1063 read_lock_bh(&tipc_net_lock);
1064 node = tipc_node_find(destaddr);
1065 if (likely(node)) {
1066 tipc_node_lock(node);
1067 l_ptr = node->active_links[selector];
1068 if (likely(l_ptr)) {
1069 if (likely(buf)) {
1070 res = link_send_buf_fast(l_ptr, buf,
1071 &sender->max_pkt);
1072 if (unlikely(res < 0))
1073 buf_discard(buf);
1074 exit:
1075 tipc_node_unlock(node);
1076 read_unlock_bh(&tipc_net_lock);
1077 return res;
1078 }
1079
1080 /* Exit if build request was invalid */
1081
1082 if (unlikely(res < 0))
1083 goto exit;
1084
1085 /* Exit if link (or bearer) is congested */
1086
1087 if (link_congested(l_ptr) ||
1088 !list_empty(&l_ptr->b_ptr->cong_links)) {
1089 res = link_schedule_port(l_ptr,
1090 sender->ref, res);
1091 goto exit;
1092 }
1093
1094 /*
1095 * Message size exceeds max_pkt hint; update hint,
1096 * then re-try fast path or fragment the message
1097 */
1098
1099 sender->max_pkt = l_ptr->max_pkt;
1100 tipc_node_unlock(node);
1101 read_unlock_bh(&tipc_net_lock);
1102
1103
1104 if ((msg_hdr_sz(hdr) + res) <= sender->max_pkt)
1105 goto again;
1106
1107 return link_send_sections_long(sender, msg_sect,
1108 num_sect, destaddr);
1109 }
1110 tipc_node_unlock(node);
1111 }
1112 read_unlock_bh(&tipc_net_lock);
1113
1114 /* Couldn't find a link to the destination node */
1115
1116 if (buf)
1117 return tipc_reject_msg(buf, TIPC_ERR_NO_NODE);
1118 if (res >= 0)
1119 return tipc_port_reject_sections(sender, hdr, msg_sect, num_sect,
1120 TIPC_ERR_NO_NODE);
1121 return res;
1122 }
1123
1124 /*
1125 * link_send_sections_long(): Entry for long messages where the
1126 * destination node is known and the header is complete,
1127 * inclusive total message length.
1128 * Link and bearer congestion status have been checked to be ok,
1129 * and are ignored if they change.
1130 *
1131 * Note that fragments do not use the full link MTU so that they won't have
1132 * to undergo refragmentation if link changeover causes them to be sent
1133 * over another link with an additional tunnel header added as prefix.
1134 * (Refragmentation will still occur if the other link has a smaller MTU.)
1135 *
1136 * Returns user data length or errno.
1137 */
1138 static int link_send_sections_long(struct tipc_port *sender,
1139 struct iovec const *msg_sect,
1140 u32 num_sect,
1141 u32 destaddr)
1142 {
1143 struct link *l_ptr;
1144 struct tipc_node *node;
1145 struct tipc_msg *hdr = &sender->phdr;
1146 u32 dsz = msg_data_sz(hdr);
1147 u32 max_pkt, fragm_sz, rest;
1148 struct tipc_msg fragm_hdr;
1149 struct sk_buff *buf, *buf_chain, *prev;
1150 u32 fragm_crs, fragm_rest, hsz, sect_rest;
1151 const unchar *sect_crs;
1152 int curr_sect;
1153 u32 fragm_no;
1154
1155 again:
1156 fragm_no = 1;
1157 max_pkt = sender->max_pkt - INT_H_SIZE;
1158 /* leave room for tunnel header in case of link changeover */
1159 fragm_sz = max_pkt - INT_H_SIZE;
1160 /* leave room for fragmentation header in each fragment */
1161 rest = dsz;
1162 fragm_crs = 0;
1163 fragm_rest = 0;
1164 sect_rest = 0;
1165 sect_crs = NULL;
1166 curr_sect = -1;
1167
1168 /* Prepare reusable fragment header: */
1169
1170 tipc_msg_init(&fragm_hdr, MSG_FRAGMENTER, FIRST_FRAGMENT,
1171 INT_H_SIZE, msg_destnode(hdr));
1172 msg_set_link_selector(&fragm_hdr, sender->ref);
1173 msg_set_size(&fragm_hdr, max_pkt);
1174 msg_set_fragm_no(&fragm_hdr, 1);
1175
1176 /* Prepare header of first fragment: */
1177
1178 buf_chain = buf = tipc_buf_acquire(max_pkt);
1179 if (!buf)
1180 return -ENOMEM;
1181 buf->next = NULL;
1182 skb_copy_to_linear_data(buf, &fragm_hdr, INT_H_SIZE);
1183 hsz = msg_hdr_sz(hdr);
1184 skb_copy_to_linear_data_offset(buf, INT_H_SIZE, hdr, hsz);
1185
1186 /* Chop up message: */
1187
1188 fragm_crs = INT_H_SIZE + hsz;
1189 fragm_rest = fragm_sz - hsz;
1190
1191 do { /* For all sections */
1192 u32 sz;
1193
1194 if (!sect_rest) {
1195 sect_rest = msg_sect[++curr_sect].iov_len;
1196 sect_crs = (const unchar *)msg_sect[curr_sect].iov_base;
1197 }
1198
1199 if (sect_rest < fragm_rest)
1200 sz = sect_rest;
1201 else
1202 sz = fragm_rest;
1203
1204 if (likely(!sender->user_port)) {
1205 if (copy_from_user(buf->data + fragm_crs, sect_crs, sz)) {
1206 error:
1207 for (; buf_chain; buf_chain = buf) {
1208 buf = buf_chain->next;
1209 buf_discard(buf_chain);
1210 }
1211 return -EFAULT;
1212 }
1213 } else
1214 skb_copy_to_linear_data_offset(buf, fragm_crs,
1215 sect_crs, sz);
1216 sect_crs += sz;
1217 sect_rest -= sz;
1218 fragm_crs += sz;
1219 fragm_rest -= sz;
1220 rest -= sz;
1221
1222 if (!fragm_rest && rest) {
1223
1224 /* Initiate new fragment: */
1225 if (rest <= fragm_sz) {
1226 fragm_sz = rest;
1227 msg_set_type(&fragm_hdr, LAST_FRAGMENT);
1228 } else {
1229 msg_set_type(&fragm_hdr, FRAGMENT);
1230 }
1231 msg_set_size(&fragm_hdr, fragm_sz + INT_H_SIZE);
1232 msg_set_fragm_no(&fragm_hdr, ++fragm_no);
1233 prev = buf;
1234 buf = tipc_buf_acquire(fragm_sz + INT_H_SIZE);
1235 if (!buf)
1236 goto error;
1237
1238 buf->next = NULL;
1239 prev->next = buf;
1240 skb_copy_to_linear_data(buf, &fragm_hdr, INT_H_SIZE);
1241 fragm_crs = INT_H_SIZE;
1242 fragm_rest = fragm_sz;
1243 }
1244 } while (rest > 0);
1245
1246 /*
1247 * Now we have a buffer chain. Select a link and check
1248 * that packet size is still OK
1249 */
1250 node = tipc_node_find(destaddr);
1251 if (likely(node)) {
1252 tipc_node_lock(node);
1253 l_ptr = node->active_links[sender->ref & 1];
1254 if (!l_ptr) {
1255 tipc_node_unlock(node);
1256 goto reject;
1257 }
1258 if (l_ptr->max_pkt < max_pkt) {
1259 sender->max_pkt = l_ptr->max_pkt;
1260 tipc_node_unlock(node);
1261 for (; buf_chain; buf_chain = buf) {
1262 buf = buf_chain->next;
1263 buf_discard(buf_chain);
1264 }
1265 goto again;
1266 }
1267 } else {
1268 reject:
1269 for (; buf_chain; buf_chain = buf) {
1270 buf = buf_chain->next;
1271 buf_discard(buf_chain);
1272 }
1273 return tipc_port_reject_sections(sender, hdr, msg_sect, num_sect,
1274 TIPC_ERR_NO_NODE);
1275 }
1276
1277 /* Append whole chain to send queue: */
1278
1279 buf = buf_chain;
1280 l_ptr->long_msg_seq_no = mod(l_ptr->long_msg_seq_no + 1);
1281 if (!l_ptr->next_out)
1282 l_ptr->next_out = buf_chain;
1283 l_ptr->stats.sent_fragmented++;
1284 while (buf) {
1285 struct sk_buff *next = buf->next;
1286 struct tipc_msg *msg = buf_msg(buf);
1287
1288 l_ptr->stats.sent_fragments++;
1289 msg_set_long_msgno(msg, l_ptr->long_msg_seq_no);
1290 link_add_to_outqueue(l_ptr, buf, msg);
1291 buf = next;
1292 }
1293
1294 /* Send it, if possible: */
1295
1296 tipc_link_push_queue(l_ptr);
1297 tipc_node_unlock(node);
1298 return dsz;
1299 }
1300
1301 /*
1302 * tipc_link_push_packet: Push one unsent packet to the media
1303 */
1304 u32 tipc_link_push_packet(struct link *l_ptr)
1305 {
1306 struct sk_buff *buf = l_ptr->first_out;
1307 u32 r_q_size = l_ptr->retransm_queue_size;
1308 u32 r_q_head = l_ptr->retransm_queue_head;
1309
1310 /* Step to position where retransmission failed, if any, */
1311 /* consider that buffers may have been released in meantime */
1312
1313 if (r_q_size && buf) {
1314 u32 last = lesser(mod(r_q_head + r_q_size),
1315 link_last_sent(l_ptr));
1316 u32 first = msg_seqno(buf_msg(buf));
1317
1318 while (buf && less(first, r_q_head)) {
1319 first = mod(first + 1);
1320 buf = buf->next;
1321 }
1322 l_ptr->retransm_queue_head = r_q_head = first;
1323 l_ptr->retransm_queue_size = r_q_size = mod(last - first);
1324 }
1325
1326 /* Continue retransmission now, if there is anything: */
1327
1328 if (r_q_size && buf) {
1329 msg_set_ack(buf_msg(buf), mod(l_ptr->next_in_no - 1));
1330 msg_set_bcast_ack(buf_msg(buf), l_ptr->owner->bclink.last_in);
1331 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) {
1332 l_ptr->retransm_queue_head = mod(++r_q_head);
1333 l_ptr->retransm_queue_size = --r_q_size;
1334 l_ptr->stats.retransmitted++;
1335 return 0;
1336 } else {
1337 l_ptr->stats.bearer_congs++;
1338 return PUSH_FAILED;
1339 }
1340 }
1341
1342 /* Send deferred protocol message, if any: */
1343
1344 buf = l_ptr->proto_msg_queue;
1345 if (buf) {
1346 msg_set_ack(buf_msg(buf), mod(l_ptr->next_in_no - 1));
1347 msg_set_bcast_ack(buf_msg(buf), l_ptr->owner->bclink.last_in);
1348 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) {
1349 l_ptr->unacked_window = 0;
1350 buf_discard(buf);
1351 l_ptr->proto_msg_queue = NULL;
1352 return 0;
1353 } else {
1354 l_ptr->stats.bearer_congs++;
1355 return PUSH_FAILED;
1356 }
1357 }
1358
1359 /* Send one deferred data message, if send window not full: */
1360
1361 buf = l_ptr->next_out;
1362 if (buf) {
1363 struct tipc_msg *msg = buf_msg(buf);
1364 u32 next = msg_seqno(msg);
1365 u32 first = msg_seqno(buf_msg(l_ptr->first_out));
1366
1367 if (mod(next - first) < l_ptr->queue_limit[0]) {
1368 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
1369 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1370 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) {
1371 if (msg_user(msg) == MSG_BUNDLER)
1372 msg_set_type(msg, CLOSED_MSG);
1373 l_ptr->next_out = buf->next;
1374 return 0;
1375 } else {
1376 l_ptr->stats.bearer_congs++;
1377 return PUSH_FAILED;
1378 }
1379 }
1380 }
1381 return PUSH_FINISHED;
1382 }
1383
1384 /*
1385 * push_queue(): push out the unsent messages of a link where
1386 * congestion has abated. Node is locked
1387 */
1388 void tipc_link_push_queue(struct link *l_ptr)
1389 {
1390 u32 res;
1391
1392 if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr))
1393 return;
1394
1395 do {
1396 res = tipc_link_push_packet(l_ptr);
1397 } while (!res);
1398
1399 if (res == PUSH_FAILED)
1400 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr);
1401 }
1402
1403 static void link_reset_all(unsigned long addr)
1404 {
1405 struct tipc_node *n_ptr;
1406 char addr_string[16];
1407 u32 i;
1408
1409 read_lock_bh(&tipc_net_lock);
1410 n_ptr = tipc_node_find((u32)addr);
1411 if (!n_ptr) {
1412 read_unlock_bh(&tipc_net_lock);
1413 return; /* node no longer exists */
1414 }
1415
1416 tipc_node_lock(n_ptr);
1417
1418 warn("Resetting all links to %s\n",
1419 tipc_addr_string_fill(addr_string, n_ptr->addr));
1420
1421 for (i = 0; i < MAX_BEARERS; i++) {
1422 if (n_ptr->links[i]) {
1423 link_print(n_ptr->links[i], "Resetting link\n");
1424 tipc_link_reset(n_ptr->links[i]);
1425 }
1426 }
1427
1428 tipc_node_unlock(n_ptr);
1429 read_unlock_bh(&tipc_net_lock);
1430 }
1431
1432 static void link_retransmit_failure(struct link *l_ptr, struct sk_buff *buf)
1433 {
1434 struct tipc_msg *msg = buf_msg(buf);
1435
1436 warn("Retransmission failure on link <%s>\n", l_ptr->name);
1437
1438 if (l_ptr->addr) {
1439
1440 /* Handle failure on standard link */
1441
1442 link_print(l_ptr, "Resetting link\n");
1443 tipc_link_reset(l_ptr);
1444
1445 } else {
1446
1447 /* Handle failure on broadcast link */
1448
1449 struct tipc_node *n_ptr;
1450 char addr_string[16];
1451
1452 info("Msg seq number: %u, ", msg_seqno(msg));
1453 info("Outstanding acks: %lu\n",
1454 (unsigned long) TIPC_SKB_CB(buf)->handle);
1455
1456 n_ptr = tipc_bclink_retransmit_to();
1457 tipc_node_lock(n_ptr);
1458
1459 tipc_addr_string_fill(addr_string, n_ptr->addr);
1460 info("Multicast link info for %s\n", addr_string);
1461 info("Supported: %d, ", n_ptr->bclink.supported);
1462 info("Acked: %u\n", n_ptr->bclink.acked);
1463 info("Last in: %u, ", n_ptr->bclink.last_in);
1464 info("Gap after: %u, ", n_ptr->bclink.gap_after);
1465 info("Gap to: %u\n", n_ptr->bclink.gap_to);
1466 info("Nack sync: %u\n\n", n_ptr->bclink.nack_sync);
1467
1468 tipc_k_signal((Handler)link_reset_all, (unsigned long)n_ptr->addr);
1469
1470 tipc_node_unlock(n_ptr);
1471
1472 l_ptr->stale_count = 0;
1473 }
1474 }
1475
1476 void tipc_link_retransmit(struct link *l_ptr, struct sk_buff *buf,
1477 u32 retransmits)
1478 {
1479 struct tipc_msg *msg;
1480
1481 if (!buf)
1482 return;
1483
1484 msg = buf_msg(buf);
1485
1486 if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr)) {
1487 if (l_ptr->retransm_queue_size == 0) {
1488 l_ptr->retransm_queue_head = msg_seqno(msg);
1489 l_ptr->retransm_queue_size = retransmits;
1490 } else {
1491 err("Unexpected retransmit on link %s (qsize=%d)\n",
1492 l_ptr->name, l_ptr->retransm_queue_size);
1493 }
1494 return;
1495 } else {
1496 /* Detect repeated retransmit failures on uncongested bearer */
1497
1498 if (l_ptr->last_retransmitted == msg_seqno(msg)) {
1499 if (++l_ptr->stale_count > 100) {
1500 link_retransmit_failure(l_ptr, buf);
1501 return;
1502 }
1503 } else {
1504 l_ptr->last_retransmitted = msg_seqno(msg);
1505 l_ptr->stale_count = 1;
1506 }
1507 }
1508
1509 while (retransmits && (buf != l_ptr->next_out) && buf) {
1510 msg = buf_msg(buf);
1511 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
1512 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1513 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) {
1514 buf = buf->next;
1515 retransmits--;
1516 l_ptr->stats.retransmitted++;
1517 } else {
1518 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr);
1519 l_ptr->stats.bearer_congs++;
1520 l_ptr->retransm_queue_head = msg_seqno(buf_msg(buf));
1521 l_ptr->retransm_queue_size = retransmits;
1522 return;
1523 }
1524 }
1525
1526 l_ptr->retransm_queue_head = l_ptr->retransm_queue_size = 0;
1527 }
1528
1529 /**
1530 * link_insert_deferred_queue - insert deferred messages back into receive chain
1531 */
1532
1533 static struct sk_buff *link_insert_deferred_queue(struct link *l_ptr,
1534 struct sk_buff *buf)
1535 {
1536 u32 seq_no;
1537
1538 if (l_ptr->oldest_deferred_in == NULL)
1539 return buf;
1540
1541 seq_no = msg_seqno(buf_msg(l_ptr->oldest_deferred_in));
1542 if (seq_no == mod(l_ptr->next_in_no)) {
1543 l_ptr->newest_deferred_in->next = buf;
1544 buf = l_ptr->oldest_deferred_in;
1545 l_ptr->oldest_deferred_in = NULL;
1546 l_ptr->deferred_inqueue_sz = 0;
1547 }
1548 return buf;
1549 }
1550
1551 /**
1552 * link_recv_buf_validate - validate basic format of received message
1553 *
1554 * This routine ensures a TIPC message has an acceptable header, and at least
1555 * as much data as the header indicates it should. The routine also ensures
1556 * that the entire message header is stored in the main fragment of the message
1557 * buffer, to simplify future access to message header fields.
1558 *
1559 * Note: Having extra info present in the message header or data areas is OK.
1560 * TIPC will ignore the excess, under the assumption that it is optional info
1561 * introduced by a later release of the protocol.
1562 */
1563
1564 static int link_recv_buf_validate(struct sk_buff *buf)
1565 {
1566 static u32 min_data_hdr_size[8] = {
1567 SHORT_H_SIZE, MCAST_H_SIZE, LONG_H_SIZE, DIR_MSG_H_SIZE,
1568 MAX_H_SIZE, MAX_H_SIZE, MAX_H_SIZE, MAX_H_SIZE
1569 };
1570
1571 struct tipc_msg *msg;
1572 u32 tipc_hdr[2];
1573 u32 size;
1574 u32 hdr_size;
1575 u32 min_hdr_size;
1576
1577 if (unlikely(buf->len < MIN_H_SIZE))
1578 return 0;
1579
1580 msg = skb_header_pointer(buf, 0, sizeof(tipc_hdr), tipc_hdr);
1581 if (msg == NULL)
1582 return 0;
1583
1584 if (unlikely(msg_version(msg) != TIPC_VERSION))
1585 return 0;
1586
1587 size = msg_size(msg);
1588 hdr_size = msg_hdr_sz(msg);
1589 min_hdr_size = msg_isdata(msg) ?
1590 min_data_hdr_size[msg_type(msg)] : INT_H_SIZE;
1591
1592 if (unlikely((hdr_size < min_hdr_size) ||
1593 (size < hdr_size) ||
1594 (buf->len < size) ||
1595 (size - hdr_size > TIPC_MAX_USER_MSG_SIZE)))
1596 return 0;
1597
1598 return pskb_may_pull(buf, hdr_size);
1599 }
1600
1601 /**
1602 * tipc_recv_msg - process TIPC messages arriving from off-node
1603 * @head: pointer to message buffer chain
1604 * @tb_ptr: pointer to bearer message arrived on
1605 *
1606 * Invoked with no locks held. Bearer pointer must point to a valid bearer
1607 * structure (i.e. cannot be NULL), but bearer can be inactive.
1608 */
1609
1610 void tipc_recv_msg(struct sk_buff *head, struct tipc_bearer *b_ptr)
1611 {
1612 read_lock_bh(&tipc_net_lock);
1613 while (head) {
1614 struct tipc_node *n_ptr;
1615 struct link *l_ptr;
1616 struct sk_buff *crs;
1617 struct sk_buff *buf = head;
1618 struct tipc_msg *msg;
1619 u32 seq_no;
1620 u32 ackd;
1621 u32 released = 0;
1622 int type;
1623
1624 head = head->next;
1625
1626 /* Ensure bearer is still enabled */
1627
1628 if (unlikely(!b_ptr->active))
1629 goto cont;
1630
1631 /* Ensure message is well-formed */
1632
1633 if (unlikely(!link_recv_buf_validate(buf)))
1634 goto cont;
1635
1636 /* Ensure message data is a single contiguous unit */
1637
1638 if (unlikely(buf_linearize(buf)))
1639 goto cont;
1640
1641 /* Handle arrival of a non-unicast link message */
1642
1643 msg = buf_msg(buf);
1644
1645 if (unlikely(msg_non_seq(msg))) {
1646 if (msg_user(msg) == LINK_CONFIG)
1647 tipc_disc_recv_msg(buf, b_ptr);
1648 else
1649 tipc_bclink_recv_pkt(buf);
1650 continue;
1651 }
1652
1653 if (unlikely(!msg_short(msg) &&
1654 (msg_destnode(msg) != tipc_own_addr)))
1655 goto cont;
1656
1657 /* Discard non-routeable messages destined for another node */
1658
1659 if (unlikely(!msg_isdata(msg) &&
1660 (msg_destnode(msg) != tipc_own_addr))) {
1661 if ((msg_user(msg) != CONN_MANAGER) &&
1662 (msg_user(msg) != MSG_FRAGMENTER))
1663 goto cont;
1664 }
1665
1666 /* Locate neighboring node that sent message */
1667
1668 n_ptr = tipc_node_find(msg_prevnode(msg));
1669 if (unlikely(!n_ptr))
1670 goto cont;
1671 tipc_node_lock(n_ptr);
1672
1673 /* Don't talk to neighbor during cleanup after last session */
1674
1675 if (n_ptr->cleanup_required) {
1676 tipc_node_unlock(n_ptr);
1677 goto cont;
1678 }
1679
1680 /* Locate unicast link endpoint that should handle message */
1681
1682 l_ptr = n_ptr->links[b_ptr->identity];
1683 if (unlikely(!l_ptr)) {
1684 tipc_node_unlock(n_ptr);
1685 goto cont;
1686 }
1687
1688 /* Validate message sequence number info */
1689
1690 seq_no = msg_seqno(msg);
1691 ackd = msg_ack(msg);
1692
1693 /* Release acked messages */
1694
1695 if (less(n_ptr->bclink.acked, msg_bcast_ack(msg))) {
1696 if (tipc_node_is_up(n_ptr) && n_ptr->bclink.supported)
1697 tipc_bclink_acknowledge(n_ptr, msg_bcast_ack(msg));
1698 }
1699
1700 crs = l_ptr->first_out;
1701 while ((crs != l_ptr->next_out) &&
1702 less_eq(msg_seqno(buf_msg(crs)), ackd)) {
1703 struct sk_buff *next = crs->next;
1704
1705 buf_discard(crs);
1706 crs = next;
1707 released++;
1708 }
1709 if (released) {
1710 l_ptr->first_out = crs;
1711 l_ptr->out_queue_size -= released;
1712 }
1713
1714 /* Try sending any messages link endpoint has pending */
1715
1716 if (unlikely(l_ptr->next_out))
1717 tipc_link_push_queue(l_ptr);
1718 if (unlikely(!list_empty(&l_ptr->waiting_ports)))
1719 tipc_link_wakeup_ports(l_ptr, 0);
1720 if (unlikely(++l_ptr->unacked_window >= TIPC_MIN_LINK_WIN)) {
1721 l_ptr->stats.sent_acks++;
1722 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, 0, 0);
1723 }
1724
1725 /* Now (finally!) process the incoming message */
1726
1727 protocol_check:
1728 if (likely(link_working_working(l_ptr))) {
1729 if (likely(seq_no == mod(l_ptr->next_in_no))) {
1730 l_ptr->next_in_no++;
1731 if (unlikely(l_ptr->oldest_deferred_in))
1732 head = link_insert_deferred_queue(l_ptr,
1733 head);
1734 if (likely(msg_is_dest(msg, tipc_own_addr))) {
1735 deliver:
1736 if (likely(msg_isdata(msg))) {
1737 tipc_node_unlock(n_ptr);
1738 tipc_port_recv_msg(buf);
1739 continue;
1740 }
1741 switch (msg_user(msg)) {
1742 case MSG_BUNDLER:
1743 l_ptr->stats.recv_bundles++;
1744 l_ptr->stats.recv_bundled +=
1745 msg_msgcnt(msg);
1746 tipc_node_unlock(n_ptr);
1747 tipc_link_recv_bundle(buf);
1748 continue;
1749 case NAME_DISTRIBUTOR:
1750 tipc_node_unlock(n_ptr);
1751 tipc_named_recv(buf);
1752 continue;
1753 case CONN_MANAGER:
1754 tipc_node_unlock(n_ptr);
1755 tipc_port_recv_proto_msg(buf);
1756 continue;
1757 case MSG_FRAGMENTER:
1758 l_ptr->stats.recv_fragments++;
1759 if (tipc_link_recv_fragment(&l_ptr->defragm_buf,
1760 &buf, &msg)) {
1761 l_ptr->stats.recv_fragmented++;
1762 goto deliver;
1763 }
1764 break;
1765 case CHANGEOVER_PROTOCOL:
1766 type = msg_type(msg);
1767 if (link_recv_changeover_msg(&l_ptr, &buf)) {
1768 msg = buf_msg(buf);
1769 seq_no = msg_seqno(msg);
1770 if (type == ORIGINAL_MSG)
1771 goto deliver;
1772 goto protocol_check;
1773 }
1774 break;
1775 default:
1776 buf_discard(buf);
1777 buf = NULL;
1778 break;
1779 }
1780 }
1781 tipc_node_unlock(n_ptr);
1782 tipc_net_route_msg(buf);
1783 continue;
1784 }
1785 link_handle_out_of_seq_msg(l_ptr, buf);
1786 head = link_insert_deferred_queue(l_ptr, head);
1787 tipc_node_unlock(n_ptr);
1788 continue;
1789 }
1790
1791 if (msg_user(msg) == LINK_PROTOCOL) {
1792 link_recv_proto_msg(l_ptr, buf);
1793 head = link_insert_deferred_queue(l_ptr, head);
1794 tipc_node_unlock(n_ptr);
1795 continue;
1796 }
1797 link_state_event(l_ptr, TRAFFIC_MSG_EVT);
1798
1799 if (link_working_working(l_ptr)) {
1800 /* Re-insert in front of queue */
1801 buf->next = head;
1802 head = buf;
1803 tipc_node_unlock(n_ptr);
1804 continue;
1805 }
1806 tipc_node_unlock(n_ptr);
1807 cont:
1808 buf_discard(buf);
1809 }
1810 read_unlock_bh(&tipc_net_lock);
1811 }
1812
1813 /*
1814 * link_defer_buf(): Sort a received out-of-sequence packet
1815 * into the deferred reception queue.
1816 * Returns the increase of the queue length,i.e. 0 or 1
1817 */
1818
1819 u32 tipc_link_defer_pkt(struct sk_buff **head,
1820 struct sk_buff **tail,
1821 struct sk_buff *buf)
1822 {
1823 struct sk_buff *prev = NULL;
1824 struct sk_buff *crs = *head;
1825 u32 seq_no = msg_seqno(buf_msg(buf));
1826
1827 buf->next = NULL;
1828
1829 /* Empty queue ? */
1830 if (*head == NULL) {
1831 *head = *tail = buf;
1832 return 1;
1833 }
1834
1835 /* Last ? */
1836 if (less(msg_seqno(buf_msg(*tail)), seq_no)) {
1837 (*tail)->next = buf;
1838 *tail = buf;
1839 return 1;
1840 }
1841
1842 /* Scan through queue and sort it in */
1843 do {
1844 struct tipc_msg *msg = buf_msg(crs);
1845
1846 if (less(seq_no, msg_seqno(msg))) {
1847 buf->next = crs;
1848 if (prev)
1849 prev->next = buf;
1850 else
1851 *head = buf;
1852 return 1;
1853 }
1854 if (seq_no == msg_seqno(msg))
1855 break;
1856 prev = crs;
1857 crs = crs->next;
1858 } while (crs);
1859
1860 /* Message is a duplicate of an existing message */
1861
1862 buf_discard(buf);
1863 return 0;
1864 }
1865
1866 /**
1867 * link_handle_out_of_seq_msg - handle arrival of out-of-sequence packet
1868 */
1869
1870 static void link_handle_out_of_seq_msg(struct link *l_ptr,
1871 struct sk_buff *buf)
1872 {
1873 u32 seq_no = msg_seqno(buf_msg(buf));
1874
1875 if (likely(msg_user(buf_msg(buf)) == LINK_PROTOCOL)) {
1876 link_recv_proto_msg(l_ptr, buf);
1877 return;
1878 }
1879
1880 /* Record OOS packet arrival (force mismatch on next timeout) */
1881
1882 l_ptr->checkpoint--;
1883
1884 /*
1885 * Discard packet if a duplicate; otherwise add it to deferred queue
1886 * and notify peer of gap as per protocol specification
1887 */
1888
1889 if (less(seq_no, mod(l_ptr->next_in_no))) {
1890 l_ptr->stats.duplicates++;
1891 buf_discard(buf);
1892 return;
1893 }
1894
1895 if (tipc_link_defer_pkt(&l_ptr->oldest_deferred_in,
1896 &l_ptr->newest_deferred_in, buf)) {
1897 l_ptr->deferred_inqueue_sz++;
1898 l_ptr->stats.deferred_recv++;
1899 if ((l_ptr->deferred_inqueue_sz % 16) == 1)
1900 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, 0, 0);
1901 } else
1902 l_ptr->stats.duplicates++;
1903 }
1904
1905 /*
1906 * Send protocol message to the other endpoint.
1907 */
1908 void tipc_link_send_proto_msg(struct link *l_ptr, u32 msg_typ, int probe_msg,
1909 u32 gap, u32 tolerance, u32 priority, u32 ack_mtu)
1910 {
1911 struct sk_buff *buf = NULL;
1912 struct tipc_msg *msg = l_ptr->pmsg;
1913 u32 msg_size = sizeof(l_ptr->proto_msg);
1914 int r_flag;
1915
1916 if (link_blocked(l_ptr))
1917 return;
1918 msg_set_type(msg, msg_typ);
1919 msg_set_net_plane(msg, l_ptr->b_ptr->net_plane);
1920 msg_set_bcast_ack(msg, mod(l_ptr->owner->bclink.last_in));
1921 msg_set_last_bcast(msg, tipc_bclink_get_last_sent());
1922
1923 if (msg_typ == STATE_MSG) {
1924 u32 next_sent = mod(l_ptr->next_out_no);
1925
1926 if (!tipc_link_is_up(l_ptr))
1927 return;
1928 if (l_ptr->next_out)
1929 next_sent = msg_seqno(buf_msg(l_ptr->next_out));
1930 msg_set_next_sent(msg, next_sent);
1931 if (l_ptr->oldest_deferred_in) {
1932 u32 rec = msg_seqno(buf_msg(l_ptr->oldest_deferred_in));
1933 gap = mod(rec - mod(l_ptr->next_in_no));
1934 }
1935 msg_set_seq_gap(msg, gap);
1936 if (gap)
1937 l_ptr->stats.sent_nacks++;
1938 msg_set_link_tolerance(msg, tolerance);
1939 msg_set_linkprio(msg, priority);
1940 msg_set_max_pkt(msg, ack_mtu);
1941 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
1942 msg_set_probe(msg, probe_msg != 0);
1943 if (probe_msg) {
1944 u32 mtu = l_ptr->max_pkt;
1945
1946 if ((mtu < l_ptr->max_pkt_target) &&
1947 link_working_working(l_ptr) &&
1948 l_ptr->fsm_msg_cnt) {
1949 msg_size = (mtu + (l_ptr->max_pkt_target - mtu)/2 + 2) & ~3;
1950 if (l_ptr->max_pkt_probes == 10) {
1951 l_ptr->max_pkt_target = (msg_size - 4);
1952 l_ptr->max_pkt_probes = 0;
1953 msg_size = (mtu + (l_ptr->max_pkt_target - mtu)/2 + 2) & ~3;
1954 }
1955 l_ptr->max_pkt_probes++;
1956 }
1957
1958 l_ptr->stats.sent_probes++;
1959 }
1960 l_ptr->stats.sent_states++;
1961 } else { /* RESET_MSG or ACTIVATE_MSG */
1962 msg_set_ack(msg, mod(l_ptr->reset_checkpoint - 1));
1963 msg_set_seq_gap(msg, 0);
1964 msg_set_next_sent(msg, 1);
1965 msg_set_probe(msg, 0);
1966 msg_set_link_tolerance(msg, l_ptr->tolerance);
1967 msg_set_linkprio(msg, l_ptr->priority);
1968 msg_set_max_pkt(msg, l_ptr->max_pkt_target);
1969 }
1970
1971 r_flag = (l_ptr->owner->working_links > tipc_link_is_up(l_ptr));
1972 msg_set_redundant_link(msg, r_flag);
1973 msg_set_linkprio(msg, l_ptr->priority);
1974
1975 /* Ensure sequence number will not fit : */
1976
1977 msg_set_seqno(msg, mod(l_ptr->next_out_no + (0xffff/2)));
1978
1979 /* Congestion? */
1980
1981 if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr)) {
1982 if (!l_ptr->proto_msg_queue) {
1983 l_ptr->proto_msg_queue =
1984 tipc_buf_acquire(sizeof(l_ptr->proto_msg));
1985 }
1986 buf = l_ptr->proto_msg_queue;
1987 if (!buf)
1988 return;
1989 skb_copy_to_linear_data(buf, msg, sizeof(l_ptr->proto_msg));
1990 return;
1991 }
1992
1993 /* Message can be sent */
1994
1995 buf = tipc_buf_acquire(msg_size);
1996 if (!buf)
1997 return;
1998
1999 skb_copy_to_linear_data(buf, msg, sizeof(l_ptr->proto_msg));
2000 msg_set_size(buf_msg(buf), msg_size);
2001
2002 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) {
2003 l_ptr->unacked_window = 0;
2004 buf_discard(buf);
2005 return;
2006 }
2007
2008 /* New congestion */
2009 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr);
2010 l_ptr->proto_msg_queue = buf;
2011 l_ptr->stats.bearer_congs++;
2012 }
2013
2014 /*
2015 * Receive protocol message :
2016 * Note that network plane id propagates through the network, and may
2017 * change at any time. The node with lowest address rules
2018 */
2019
2020 static void link_recv_proto_msg(struct link *l_ptr, struct sk_buff *buf)
2021 {
2022 u32 rec_gap = 0;
2023 u32 max_pkt_info;
2024 u32 max_pkt_ack;
2025 u32 msg_tol;
2026 struct tipc_msg *msg = buf_msg(buf);
2027
2028 if (link_blocked(l_ptr))
2029 goto exit;
2030
2031 /* record unnumbered packet arrival (force mismatch on next timeout) */
2032
2033 l_ptr->checkpoint--;
2034
2035 if (l_ptr->b_ptr->net_plane != msg_net_plane(msg))
2036 if (tipc_own_addr > msg_prevnode(msg))
2037 l_ptr->b_ptr->net_plane = msg_net_plane(msg);
2038
2039 l_ptr->owner->permit_changeover = msg_redundant_link(msg);
2040
2041 switch (msg_type(msg)) {
2042
2043 case RESET_MSG:
2044 if (!link_working_unknown(l_ptr) &&
2045 (l_ptr->peer_session != INVALID_SESSION)) {
2046 if (msg_session(msg) == l_ptr->peer_session)
2047 break; /* duplicate: ignore */
2048 }
2049 /* fall thru' */
2050 case ACTIVATE_MSG:
2051 /* Update link settings according other endpoint's values */
2052
2053 strcpy((strrchr(l_ptr->name, ':') + 1), (char *)msg_data(msg));
2054
2055 msg_tol = msg_link_tolerance(msg);
2056 if (msg_tol > l_ptr->tolerance)
2057 link_set_supervision_props(l_ptr, msg_tol);
2058
2059 if (msg_linkprio(msg) > l_ptr->priority)
2060 l_ptr->priority = msg_linkprio(msg);
2061
2062 max_pkt_info = msg_max_pkt(msg);
2063 if (max_pkt_info) {
2064 if (max_pkt_info < l_ptr->max_pkt_target)
2065 l_ptr->max_pkt_target = max_pkt_info;
2066 if (l_ptr->max_pkt > l_ptr->max_pkt_target)
2067 l_ptr->max_pkt = l_ptr->max_pkt_target;
2068 } else {
2069 l_ptr->max_pkt = l_ptr->max_pkt_target;
2070 }
2071 l_ptr->owner->bclink.supported = (max_pkt_info != 0);
2072
2073 link_state_event(l_ptr, msg_type(msg));
2074
2075 l_ptr->peer_session = msg_session(msg);
2076 l_ptr->peer_bearer_id = msg_bearer_id(msg);
2077
2078 /* Synchronize broadcast sequence numbers */
2079 if (!tipc_node_redundant_links(l_ptr->owner))
2080 l_ptr->owner->bclink.last_in = mod(msg_last_bcast(msg));
2081 break;
2082 case STATE_MSG:
2083
2084 msg_tol = msg_link_tolerance(msg);
2085 if (msg_tol)
2086 link_set_supervision_props(l_ptr, msg_tol);
2087
2088 if (msg_linkprio(msg) &&
2089 (msg_linkprio(msg) != l_ptr->priority)) {
2090 warn("Resetting link <%s>, priority change %u->%u\n",
2091 l_ptr->name, l_ptr->priority, msg_linkprio(msg));
2092 l_ptr->priority = msg_linkprio(msg);
2093 tipc_link_reset(l_ptr); /* Enforce change to take effect */
2094 break;
2095 }
2096 link_state_event(l_ptr, TRAFFIC_MSG_EVT);
2097 l_ptr->stats.recv_states++;
2098 if (link_reset_unknown(l_ptr))
2099 break;
2100
2101 if (less_eq(mod(l_ptr->next_in_no), msg_next_sent(msg))) {
2102 rec_gap = mod(msg_next_sent(msg) -
2103 mod(l_ptr->next_in_no));
2104 }
2105
2106 max_pkt_ack = msg_max_pkt(msg);
2107 if (max_pkt_ack > l_ptr->max_pkt) {
2108 l_ptr->max_pkt = max_pkt_ack;
2109 l_ptr->max_pkt_probes = 0;
2110 }
2111
2112 max_pkt_ack = 0;
2113 if (msg_probe(msg)) {
2114 l_ptr->stats.recv_probes++;
2115 if (msg_size(msg) > sizeof(l_ptr->proto_msg))
2116 max_pkt_ack = msg_size(msg);
2117 }
2118
2119 /* Protocol message before retransmits, reduce loss risk */
2120
2121 tipc_bclink_check_gap(l_ptr->owner, msg_last_bcast(msg));
2122
2123 if (rec_gap || (msg_probe(msg))) {
2124 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
2125 0, rec_gap, 0, 0, max_pkt_ack);
2126 }
2127 if (msg_seq_gap(msg)) {
2128 l_ptr->stats.recv_nacks++;
2129 tipc_link_retransmit(l_ptr, l_ptr->first_out,
2130 msg_seq_gap(msg));
2131 }
2132 break;
2133 }
2134 exit:
2135 buf_discard(buf);
2136 }
2137
2138
2139 /*
2140 * tipc_link_tunnel(): Send one message via a link belonging to
2141 * another bearer. Owner node is locked.
2142 */
2143 static void tipc_link_tunnel(struct link *l_ptr,
2144 struct tipc_msg *tunnel_hdr,
2145 struct tipc_msg *msg,
2146 u32 selector)
2147 {
2148 struct link *tunnel;
2149 struct sk_buff *buf;
2150 u32 length = msg_size(msg);
2151
2152 tunnel = l_ptr->owner->active_links[selector & 1];
2153 if (!tipc_link_is_up(tunnel)) {
2154 warn("Link changeover error, "
2155 "tunnel link no longer available\n");
2156 return;
2157 }
2158 msg_set_size(tunnel_hdr, length + INT_H_SIZE);
2159 buf = tipc_buf_acquire(length + INT_H_SIZE);
2160 if (!buf) {
2161 warn("Link changeover error, "
2162 "unable to send tunnel msg\n");
2163 return;
2164 }
2165 skb_copy_to_linear_data(buf, tunnel_hdr, INT_H_SIZE);
2166 skb_copy_to_linear_data_offset(buf, INT_H_SIZE, msg, length);
2167 tipc_link_send_buf(tunnel, buf);
2168 }
2169
2170
2171
2172 /*
2173 * changeover(): Send whole message queue via the remaining link
2174 * Owner node is locked.
2175 */
2176
2177 void tipc_link_changeover(struct link *l_ptr)
2178 {
2179 u32 msgcount = l_ptr->out_queue_size;
2180 struct sk_buff *crs = l_ptr->first_out;
2181 struct link *tunnel = l_ptr->owner->active_links[0];
2182 struct tipc_msg tunnel_hdr;
2183 int split_bundles;
2184
2185 if (!tunnel)
2186 return;
2187
2188 if (!l_ptr->owner->permit_changeover) {
2189 warn("Link changeover error, "
2190 "peer did not permit changeover\n");
2191 return;
2192 }
2193
2194 tipc_msg_init(&tunnel_hdr, CHANGEOVER_PROTOCOL,
2195 ORIGINAL_MSG, INT_H_SIZE, l_ptr->addr);
2196 msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id);
2197 msg_set_msgcnt(&tunnel_hdr, msgcount);
2198
2199 if (!l_ptr->first_out) {
2200 struct sk_buff *buf;
2201
2202 buf = tipc_buf_acquire(INT_H_SIZE);
2203 if (buf) {
2204 skb_copy_to_linear_data(buf, &tunnel_hdr, INT_H_SIZE);
2205 msg_set_size(&tunnel_hdr, INT_H_SIZE);
2206 tipc_link_send_buf(tunnel, buf);
2207 } else {
2208 warn("Link changeover error, "
2209 "unable to send changeover msg\n");
2210 }
2211 return;
2212 }
2213
2214 split_bundles = (l_ptr->owner->active_links[0] !=
2215 l_ptr->owner->active_links[1]);
2216
2217 while (crs) {
2218 struct tipc_msg *msg = buf_msg(crs);
2219
2220 if ((msg_user(msg) == MSG_BUNDLER) && split_bundles) {
2221 struct tipc_msg *m = msg_get_wrapped(msg);
2222 unchar *pos = (unchar *)m;
2223
2224 msgcount = msg_msgcnt(msg);
2225 while (msgcount--) {
2226 msg_set_seqno(m, msg_seqno(msg));
2227 tipc_link_tunnel(l_ptr, &tunnel_hdr, m,
2228 msg_link_selector(m));
2229 pos += align(msg_size(m));
2230 m = (struct tipc_msg *)pos;
2231 }
2232 } else {
2233 tipc_link_tunnel(l_ptr, &tunnel_hdr, msg,
2234 msg_link_selector(msg));
2235 }
2236 crs = crs->next;
2237 }
2238 }
2239
2240 void tipc_link_send_duplicate(struct link *l_ptr, struct link *tunnel)
2241 {
2242 struct sk_buff *iter;
2243 struct tipc_msg tunnel_hdr;
2244
2245 tipc_msg_init(&tunnel_hdr, CHANGEOVER_PROTOCOL,
2246 DUPLICATE_MSG, INT_H_SIZE, l_ptr->addr);
2247 msg_set_msgcnt(&tunnel_hdr, l_ptr->out_queue_size);
2248 msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id);
2249 iter = l_ptr->first_out;
2250 while (iter) {
2251 struct sk_buff *outbuf;
2252 struct tipc_msg *msg = buf_msg(iter);
2253 u32 length = msg_size(msg);
2254
2255 if (msg_user(msg) == MSG_BUNDLER)
2256 msg_set_type(msg, CLOSED_MSG);
2257 msg_set_ack(msg, mod(l_ptr->next_in_no - 1)); /* Update */
2258 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
2259 msg_set_size(&tunnel_hdr, length + INT_H_SIZE);
2260 outbuf = tipc_buf_acquire(length + INT_H_SIZE);
2261 if (outbuf == NULL) {
2262 warn("Link changeover error, "
2263 "unable to send duplicate msg\n");
2264 return;
2265 }
2266 skb_copy_to_linear_data(outbuf, &tunnel_hdr, INT_H_SIZE);
2267 skb_copy_to_linear_data_offset(outbuf, INT_H_SIZE, iter->data,
2268 length);
2269 tipc_link_send_buf(tunnel, outbuf);
2270 if (!tipc_link_is_up(l_ptr))
2271 return;
2272 iter = iter->next;
2273 }
2274 }
2275
2276
2277
2278 /**
2279 * buf_extract - extracts embedded TIPC message from another message
2280 * @skb: encapsulating message buffer
2281 * @from_pos: offset to extract from
2282 *
2283 * Returns a new message buffer containing an embedded message. The
2284 * encapsulating message itself is left unchanged.
2285 */
2286
2287 static struct sk_buff *buf_extract(struct sk_buff *skb, u32 from_pos)
2288 {
2289 struct tipc_msg *msg = (struct tipc_msg *)(skb->data + from_pos);
2290 u32 size = msg_size(msg);
2291 struct sk_buff *eb;
2292
2293 eb = tipc_buf_acquire(size);
2294 if (eb)
2295 skb_copy_to_linear_data(eb, msg, size);
2296 return eb;
2297 }
2298
2299 /*
2300 * link_recv_changeover_msg(): Receive tunneled packet sent
2301 * via other link. Node is locked. Return extracted buffer.
2302 */
2303
2304 static int link_recv_changeover_msg(struct link **l_ptr,
2305 struct sk_buff **buf)
2306 {
2307 struct sk_buff *tunnel_buf = *buf;
2308 struct link *dest_link;
2309 struct tipc_msg *msg;
2310 struct tipc_msg *tunnel_msg = buf_msg(tunnel_buf);
2311 u32 msg_typ = msg_type(tunnel_msg);
2312 u32 msg_count = msg_msgcnt(tunnel_msg);
2313
2314 dest_link = (*l_ptr)->owner->links[msg_bearer_id(tunnel_msg)];
2315 if (!dest_link)
2316 goto exit;
2317 if (dest_link == *l_ptr) {
2318 err("Unexpected changeover message on link <%s>\n",
2319 (*l_ptr)->name);
2320 goto exit;
2321 }
2322 *l_ptr = dest_link;
2323 msg = msg_get_wrapped(tunnel_msg);
2324
2325 if (msg_typ == DUPLICATE_MSG) {
2326 if (less(msg_seqno(msg), mod(dest_link->next_in_no)))
2327 goto exit;
2328 *buf = buf_extract(tunnel_buf, INT_H_SIZE);
2329 if (*buf == NULL) {
2330 warn("Link changeover error, duplicate msg dropped\n");
2331 goto exit;
2332 }
2333 buf_discard(tunnel_buf);
2334 return 1;
2335 }
2336
2337 /* First original message ?: */
2338
2339 if (tipc_link_is_up(dest_link)) {
2340 info("Resetting link <%s>, changeover initiated by peer\n",
2341 dest_link->name);
2342 tipc_link_reset(dest_link);
2343 dest_link->exp_msg_count = msg_count;
2344 if (!msg_count)
2345 goto exit;
2346 } else if (dest_link->exp_msg_count == START_CHANGEOVER) {
2347 dest_link->exp_msg_count = msg_count;
2348 if (!msg_count)
2349 goto exit;
2350 }
2351
2352 /* Receive original message */
2353
2354 if (dest_link->exp_msg_count == 0) {
2355 warn("Link switchover error, "
2356 "got too many tunnelled messages\n");
2357 goto exit;
2358 }
2359 dest_link->exp_msg_count--;
2360 if (less(msg_seqno(msg), dest_link->reset_checkpoint)) {
2361 goto exit;
2362 } else {
2363 *buf = buf_extract(tunnel_buf, INT_H_SIZE);
2364 if (*buf != NULL) {
2365 buf_discard(tunnel_buf);
2366 return 1;
2367 } else {
2368 warn("Link changeover error, original msg dropped\n");
2369 }
2370 }
2371 exit:
2372 *buf = NULL;
2373 buf_discard(tunnel_buf);
2374 return 0;
2375 }
2376
2377 /*
2378 * Bundler functionality:
2379 */
2380 void tipc_link_recv_bundle(struct sk_buff *buf)
2381 {
2382 u32 msgcount = msg_msgcnt(buf_msg(buf));
2383 u32 pos = INT_H_SIZE;
2384 struct sk_buff *obuf;
2385
2386 while (msgcount--) {
2387 obuf = buf_extract(buf, pos);
2388 if (obuf == NULL) {
2389 warn("Link unable to unbundle message(s)\n");
2390 break;
2391 }
2392 pos += align(msg_size(buf_msg(obuf)));
2393 tipc_net_route_msg(obuf);
2394 }
2395 buf_discard(buf);
2396 }
2397
2398 /*
2399 * Fragmentation/defragmentation:
2400 */
2401
2402
2403 /*
2404 * link_send_long_buf: Entry for buffers needing fragmentation.
2405 * The buffer is complete, inclusive total message length.
2406 * Returns user data length.
2407 */
2408 static int link_send_long_buf(struct link *l_ptr, struct sk_buff *buf)
2409 {
2410 struct tipc_msg *inmsg = buf_msg(buf);
2411 struct tipc_msg fragm_hdr;
2412 u32 insize = msg_size(inmsg);
2413 u32 dsz = msg_data_sz(inmsg);
2414 unchar *crs = buf->data;
2415 u32 rest = insize;
2416 u32 pack_sz = l_ptr->max_pkt;
2417 u32 fragm_sz = pack_sz - INT_H_SIZE;
2418 u32 fragm_no = 1;
2419 u32 destaddr;
2420
2421 if (msg_short(inmsg))
2422 destaddr = l_ptr->addr;
2423 else
2424 destaddr = msg_destnode(inmsg);
2425
2426 /* Prepare reusable fragment header: */
2427
2428 tipc_msg_init(&fragm_hdr, MSG_FRAGMENTER, FIRST_FRAGMENT,
2429 INT_H_SIZE, destaddr);
2430 msg_set_link_selector(&fragm_hdr, msg_link_selector(inmsg));
2431 msg_set_long_msgno(&fragm_hdr, mod(l_ptr->long_msg_seq_no++));
2432 msg_set_fragm_no(&fragm_hdr, fragm_no);
2433 l_ptr->stats.sent_fragmented++;
2434
2435 /* Chop up message: */
2436
2437 while (rest > 0) {
2438 struct sk_buff *fragm;
2439
2440 if (rest <= fragm_sz) {
2441 fragm_sz = rest;
2442 msg_set_type(&fragm_hdr, LAST_FRAGMENT);
2443 }
2444 fragm = tipc_buf_acquire(fragm_sz + INT_H_SIZE);
2445 if (fragm == NULL) {
2446 warn("Link unable to fragment message\n");
2447 dsz = -ENOMEM;
2448 goto exit;
2449 }
2450 msg_set_size(&fragm_hdr, fragm_sz + INT_H_SIZE);
2451 skb_copy_to_linear_data(fragm, &fragm_hdr, INT_H_SIZE);
2452 skb_copy_to_linear_data_offset(fragm, INT_H_SIZE, crs,
2453 fragm_sz);
2454 /* Send queued messages first, if any: */
2455
2456 l_ptr->stats.sent_fragments++;
2457 tipc_link_send_buf(l_ptr, fragm);
2458 if (!tipc_link_is_up(l_ptr))
2459 return dsz;
2460 msg_set_fragm_no(&fragm_hdr, ++fragm_no);
2461 rest -= fragm_sz;
2462 crs += fragm_sz;
2463 msg_set_type(&fragm_hdr, FRAGMENT);
2464 }
2465 exit:
2466 buf_discard(buf);
2467 return dsz;
2468 }
2469
2470 /*
2471 * A pending message being re-assembled must store certain values
2472 * to handle subsequent fragments correctly. The following functions
2473 * help storing these values in unused, available fields in the
2474 * pending message. This makes dynamic memory allocation unnecessary.
2475 */
2476
2477 static void set_long_msg_seqno(struct sk_buff *buf, u32 seqno)
2478 {
2479 msg_set_seqno(buf_msg(buf), seqno);
2480 }
2481
2482 static u32 get_fragm_size(struct sk_buff *buf)
2483 {
2484 return msg_ack(buf_msg(buf));
2485 }
2486
2487 static void set_fragm_size(struct sk_buff *buf, u32 sz)
2488 {
2489 msg_set_ack(buf_msg(buf), sz);
2490 }
2491
2492 static u32 get_expected_frags(struct sk_buff *buf)
2493 {
2494 return msg_bcast_ack(buf_msg(buf));
2495 }
2496
2497 static void set_expected_frags(struct sk_buff *buf, u32 exp)
2498 {
2499 msg_set_bcast_ack(buf_msg(buf), exp);
2500 }
2501
2502 static u32 get_timer_cnt(struct sk_buff *buf)
2503 {
2504 return msg_reroute_cnt(buf_msg(buf));
2505 }
2506
2507 static void incr_timer_cnt(struct sk_buff *buf)
2508 {
2509 msg_incr_reroute_cnt(buf_msg(buf));
2510 }
2511
2512 /*
2513 * tipc_link_recv_fragment(): Called with node lock on. Returns
2514 * the reassembled buffer if message is complete.
2515 */
2516 int tipc_link_recv_fragment(struct sk_buff **pending, struct sk_buff **fb,
2517 struct tipc_msg **m)
2518 {
2519 struct sk_buff *prev = NULL;
2520 struct sk_buff *fbuf = *fb;
2521 struct tipc_msg *fragm = buf_msg(fbuf);
2522 struct sk_buff *pbuf = *pending;
2523 u32 long_msg_seq_no = msg_long_msgno(fragm);
2524
2525 *fb = NULL;
2526
2527 /* Is there an incomplete message waiting for this fragment? */
2528
2529 while (pbuf && ((msg_seqno(buf_msg(pbuf)) != long_msg_seq_no) ||
2530 (msg_orignode(fragm) != msg_orignode(buf_msg(pbuf))))) {
2531 prev = pbuf;
2532 pbuf = pbuf->next;
2533 }
2534
2535 if (!pbuf && (msg_type(fragm) == FIRST_FRAGMENT)) {
2536 struct tipc_msg *imsg = (struct tipc_msg *)msg_data(fragm);
2537 u32 msg_sz = msg_size(imsg);
2538 u32 fragm_sz = msg_data_sz(fragm);
2539 u32 exp_fragm_cnt = msg_sz/fragm_sz + !!(msg_sz % fragm_sz);
2540 u32 max = TIPC_MAX_USER_MSG_SIZE + LONG_H_SIZE;
2541 if (msg_type(imsg) == TIPC_MCAST_MSG)
2542 max = TIPC_MAX_USER_MSG_SIZE + MCAST_H_SIZE;
2543 if (msg_size(imsg) > max) {
2544 buf_discard(fbuf);
2545 return 0;
2546 }
2547 pbuf = tipc_buf_acquire(msg_size(imsg));
2548 if (pbuf != NULL) {
2549 pbuf->next = *pending;
2550 *pending = pbuf;
2551 skb_copy_to_linear_data(pbuf, imsg,
2552 msg_data_sz(fragm));
2553 /* Prepare buffer for subsequent fragments. */
2554
2555 set_long_msg_seqno(pbuf, long_msg_seq_no);
2556 set_fragm_size(pbuf, fragm_sz);
2557 set_expected_frags(pbuf, exp_fragm_cnt - 1);
2558 } else {
2559 warn("Link unable to reassemble fragmented message\n");
2560 }
2561 buf_discard(fbuf);
2562 return 0;
2563 } else if (pbuf && (msg_type(fragm) != FIRST_FRAGMENT)) {
2564 u32 dsz = msg_data_sz(fragm);
2565 u32 fsz = get_fragm_size(pbuf);
2566 u32 crs = ((msg_fragm_no(fragm) - 1) * fsz);
2567 u32 exp_frags = get_expected_frags(pbuf) - 1;
2568 skb_copy_to_linear_data_offset(pbuf, crs,
2569 msg_data(fragm), dsz);
2570 buf_discard(fbuf);
2571
2572 /* Is message complete? */
2573
2574 if (exp_frags == 0) {
2575 if (prev)
2576 prev->next = pbuf->next;
2577 else
2578 *pending = pbuf->next;
2579 msg_reset_reroute_cnt(buf_msg(pbuf));
2580 *fb = pbuf;
2581 *m = buf_msg(pbuf);
2582 return 1;
2583 }
2584 set_expected_frags(pbuf, exp_frags);
2585 return 0;
2586 }
2587 buf_discard(fbuf);
2588 return 0;
2589 }
2590
2591 /**
2592 * link_check_defragm_bufs - flush stale incoming message fragments
2593 * @l_ptr: pointer to link
2594 */
2595
2596 static void link_check_defragm_bufs(struct link *l_ptr)
2597 {
2598 struct sk_buff *prev = NULL;
2599 struct sk_buff *next = NULL;
2600 struct sk_buff *buf = l_ptr->defragm_buf;
2601
2602 if (!buf)
2603 return;
2604 if (!link_working_working(l_ptr))
2605 return;
2606 while (buf) {
2607 u32 cnt = get_timer_cnt(buf);
2608
2609 next = buf->next;
2610 if (cnt < 4) {
2611 incr_timer_cnt(buf);
2612 prev = buf;
2613 } else {
2614 if (prev)
2615 prev->next = buf->next;
2616 else
2617 l_ptr->defragm_buf = buf->next;
2618 buf_discard(buf);
2619 }
2620 buf = next;
2621 }
2622 }
2623
2624
2625
2626 static void link_set_supervision_props(struct link *l_ptr, u32 tolerance)
2627 {
2628 if ((tolerance < TIPC_MIN_LINK_TOL) || (tolerance > TIPC_MAX_LINK_TOL))
2629 return;
2630
2631 l_ptr->tolerance = tolerance;
2632 l_ptr->continuity_interval =
2633 ((tolerance / 4) > 500) ? 500 : tolerance / 4;
2634 l_ptr->abort_limit = tolerance / (l_ptr->continuity_interval / 4);
2635 }
2636
2637
2638 void tipc_link_set_queue_limits(struct link *l_ptr, u32 window)
2639 {
2640 /* Data messages from this node, inclusive FIRST_FRAGM */
2641 l_ptr->queue_limit[TIPC_LOW_IMPORTANCE] = window;
2642 l_ptr->queue_limit[TIPC_MEDIUM_IMPORTANCE] = (window / 3) * 4;
2643 l_ptr->queue_limit[TIPC_HIGH_IMPORTANCE] = (window / 3) * 5;
2644 l_ptr->queue_limit[TIPC_CRITICAL_IMPORTANCE] = (window / 3) * 6;
2645 /* Transiting data messages,inclusive FIRST_FRAGM */
2646 l_ptr->queue_limit[TIPC_LOW_IMPORTANCE + 4] = 300;
2647 l_ptr->queue_limit[TIPC_MEDIUM_IMPORTANCE + 4] = 600;
2648 l_ptr->queue_limit[TIPC_HIGH_IMPORTANCE + 4] = 900;
2649 l_ptr->queue_limit[TIPC_CRITICAL_IMPORTANCE + 4] = 1200;
2650 l_ptr->queue_limit[CONN_MANAGER] = 1200;
2651 l_ptr->queue_limit[CHANGEOVER_PROTOCOL] = 2500;
2652 l_ptr->queue_limit[NAME_DISTRIBUTOR] = 3000;
2653 /* FRAGMENT and LAST_FRAGMENT packets */
2654 l_ptr->queue_limit[MSG_FRAGMENTER] = 4000;
2655 }
2656
2657 /**
2658 * link_find_link - locate link by name
2659 * @name - ptr to link name string
2660 * @node - ptr to area to be filled with ptr to associated node
2661 *
2662 * Caller must hold 'tipc_net_lock' to ensure node and bearer are not deleted;
2663 * this also prevents link deletion.
2664 *
2665 * Returns pointer to link (or 0 if invalid link name).
2666 */
2667
2668 static struct link *link_find_link(const char *name, struct tipc_node **node)
2669 {
2670 struct link_name link_name_parts;
2671 struct tipc_bearer *b_ptr;
2672 struct link *l_ptr;
2673
2674 if (!link_name_validate(name, &link_name_parts))
2675 return NULL;
2676
2677 b_ptr = tipc_bearer_find_interface(link_name_parts.if_local);
2678 if (!b_ptr)
2679 return NULL;
2680
2681 *node = tipc_node_find(link_name_parts.addr_peer);
2682 if (!*node)
2683 return NULL;
2684
2685 l_ptr = (*node)->links[b_ptr->identity];
2686 if (!l_ptr || strcmp(l_ptr->name, name))
2687 return NULL;
2688
2689 return l_ptr;
2690 }
2691
2692 struct sk_buff *tipc_link_cmd_config(const void *req_tlv_area, int req_tlv_space,
2693 u16 cmd)
2694 {
2695 struct tipc_link_config *args;
2696 u32 new_value;
2697 struct link *l_ptr;
2698 struct tipc_node *node;
2699 int res;
2700
2701 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_CONFIG))
2702 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
2703
2704 args = (struct tipc_link_config *)TLV_DATA(req_tlv_area);
2705 new_value = ntohl(args->value);
2706
2707 if (!strcmp(args->name, tipc_bclink_name)) {
2708 if ((cmd == TIPC_CMD_SET_LINK_WINDOW) &&
2709 (tipc_bclink_set_queue_limits(new_value) == 0))
2710 return tipc_cfg_reply_none();
2711 return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED
2712 " (cannot change setting on broadcast link)");
2713 }
2714
2715 read_lock_bh(&tipc_net_lock);
2716 l_ptr = link_find_link(args->name, &node);
2717 if (!l_ptr) {
2718 read_unlock_bh(&tipc_net_lock);
2719 return tipc_cfg_reply_error_string("link not found");
2720 }
2721
2722 tipc_node_lock(node);
2723 res = -EINVAL;
2724 switch (cmd) {
2725 case TIPC_CMD_SET_LINK_TOL:
2726 if ((new_value >= TIPC_MIN_LINK_TOL) &&
2727 (new_value <= TIPC_MAX_LINK_TOL)) {
2728 link_set_supervision_props(l_ptr, new_value);
2729 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
2730 0, 0, new_value, 0, 0);
2731 res = 0;
2732 }
2733 break;
2734 case TIPC_CMD_SET_LINK_PRI:
2735 if ((new_value >= TIPC_MIN_LINK_PRI) &&
2736 (new_value <= TIPC_MAX_LINK_PRI)) {
2737 l_ptr->priority = new_value;
2738 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
2739 0, 0, 0, new_value, 0);
2740 res = 0;
2741 }
2742 break;
2743 case TIPC_CMD_SET_LINK_WINDOW:
2744 if ((new_value >= TIPC_MIN_LINK_WIN) &&
2745 (new_value <= TIPC_MAX_LINK_WIN)) {
2746 tipc_link_set_queue_limits(l_ptr, new_value);
2747 res = 0;
2748 }
2749 break;
2750 }
2751 tipc_node_unlock(node);
2752
2753 read_unlock_bh(&tipc_net_lock);
2754 if (res)
2755 return tipc_cfg_reply_error_string("cannot change link setting");
2756
2757 return tipc_cfg_reply_none();
2758 }
2759
2760 /**
2761 * link_reset_statistics - reset link statistics
2762 * @l_ptr: pointer to link
2763 */
2764
2765 static void link_reset_statistics(struct link *l_ptr)
2766 {
2767 memset(&l_ptr->stats, 0, sizeof(l_ptr->stats));
2768 l_ptr->stats.sent_info = l_ptr->next_out_no;
2769 l_ptr->stats.recv_info = l_ptr->next_in_no;
2770 }
2771
2772 struct sk_buff *tipc_link_cmd_reset_stats(const void *req_tlv_area, int req_tlv_space)
2773 {
2774 char *link_name;
2775 struct link *l_ptr;
2776 struct tipc_node *node;
2777
2778 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_NAME))
2779 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
2780
2781 link_name = (char *)TLV_DATA(req_tlv_area);
2782 if (!strcmp(link_name, tipc_bclink_name)) {
2783 if (tipc_bclink_reset_stats())
2784 return tipc_cfg_reply_error_string("link not found");
2785 return tipc_cfg_reply_none();
2786 }
2787
2788 read_lock_bh(&tipc_net_lock);
2789 l_ptr = link_find_link(link_name, &node);
2790 if (!l_ptr) {
2791 read_unlock_bh(&tipc_net_lock);
2792 return tipc_cfg_reply_error_string("link not found");
2793 }
2794
2795 tipc_node_lock(node);
2796 link_reset_statistics(l_ptr);
2797 tipc_node_unlock(node);
2798 read_unlock_bh(&tipc_net_lock);
2799 return tipc_cfg_reply_none();
2800 }
2801
2802 /**
2803 * percent - convert count to a percentage of total (rounding up or down)
2804 */
2805
2806 static u32 percent(u32 count, u32 total)
2807 {
2808 return (count * 100 + (total / 2)) / total;
2809 }
2810
2811 /**
2812 * tipc_link_stats - print link statistics
2813 * @name: link name
2814 * @buf: print buffer area
2815 * @buf_size: size of print buffer area
2816 *
2817 * Returns length of print buffer data string (or 0 if error)
2818 */
2819
2820 static int tipc_link_stats(const char *name, char *buf, const u32 buf_size)
2821 {
2822 struct print_buf pb;
2823 struct link *l_ptr;
2824 struct tipc_node *node;
2825 char *status;
2826 u32 profile_total = 0;
2827
2828 if (!strcmp(name, tipc_bclink_name))
2829 return tipc_bclink_stats(buf, buf_size);
2830
2831 tipc_printbuf_init(&pb, buf, buf_size);
2832
2833 read_lock_bh(&tipc_net_lock);
2834 l_ptr = link_find_link(name, &node);
2835 if (!l_ptr) {
2836 read_unlock_bh(&tipc_net_lock);
2837 return 0;
2838 }
2839 tipc_node_lock(node);
2840
2841 if (tipc_link_is_active(l_ptr))
2842 status = "ACTIVE";
2843 else if (tipc_link_is_up(l_ptr))
2844 status = "STANDBY";
2845 else
2846 status = "DEFUNCT";
2847 tipc_printf(&pb, "Link <%s>\n"
2848 " %s MTU:%u Priority:%u Tolerance:%u ms"
2849 " Window:%u packets\n",
2850 l_ptr->name, status, l_ptr->max_pkt,
2851 l_ptr->priority, l_ptr->tolerance, l_ptr->queue_limit[0]);
2852 tipc_printf(&pb, " RX packets:%u fragments:%u/%u bundles:%u/%u\n",
2853 l_ptr->next_in_no - l_ptr->stats.recv_info,
2854 l_ptr->stats.recv_fragments,
2855 l_ptr->stats.recv_fragmented,
2856 l_ptr->stats.recv_bundles,
2857 l_ptr->stats.recv_bundled);
2858 tipc_printf(&pb, " TX packets:%u fragments:%u/%u bundles:%u/%u\n",
2859 l_ptr->next_out_no - l_ptr->stats.sent_info,
2860 l_ptr->stats.sent_fragments,
2861 l_ptr->stats.sent_fragmented,
2862 l_ptr->stats.sent_bundles,
2863 l_ptr->stats.sent_bundled);
2864 profile_total = l_ptr->stats.msg_length_counts;
2865 if (!profile_total)
2866 profile_total = 1;
2867 tipc_printf(&pb, " TX profile sample:%u packets average:%u octets\n"
2868 " 0-64:%u%% -256:%u%% -1024:%u%% -4096:%u%% "
2869 "-16354:%u%% -32768:%u%% -66000:%u%%\n",
2870 l_ptr->stats.msg_length_counts,
2871 l_ptr->stats.msg_lengths_total / profile_total,
2872 percent(l_ptr->stats.msg_length_profile[0], profile_total),
2873 percent(l_ptr->stats.msg_length_profile[1], profile_total),
2874 percent(l_ptr->stats.msg_length_profile[2], profile_total),
2875 percent(l_ptr->stats.msg_length_profile[3], profile_total),
2876 percent(l_ptr->stats.msg_length_profile[4], profile_total),
2877 percent(l_ptr->stats.msg_length_profile[5], profile_total),
2878 percent(l_ptr->stats.msg_length_profile[6], profile_total));
2879 tipc_printf(&pb, " RX states:%u probes:%u naks:%u defs:%u dups:%u\n",
2880 l_ptr->stats.recv_states,
2881 l_ptr->stats.recv_probes,
2882 l_ptr->stats.recv_nacks,
2883 l_ptr->stats.deferred_recv,
2884 l_ptr->stats.duplicates);
2885 tipc_printf(&pb, " TX states:%u probes:%u naks:%u acks:%u dups:%u\n",
2886 l_ptr->stats.sent_states,
2887 l_ptr->stats.sent_probes,
2888 l_ptr->stats.sent_nacks,
2889 l_ptr->stats.sent_acks,
2890 l_ptr->stats.retransmitted);
2891 tipc_printf(&pb, " Congestion bearer:%u link:%u Send queue max:%u avg:%u\n",
2892 l_ptr->stats.bearer_congs,
2893 l_ptr->stats.link_congs,
2894 l_ptr->stats.max_queue_sz,
2895 l_ptr->stats.queue_sz_counts
2896 ? (l_ptr->stats.accu_queue_sz / l_ptr->stats.queue_sz_counts)
2897 : 0);
2898
2899 tipc_node_unlock(node);
2900 read_unlock_bh(&tipc_net_lock);
2901 return tipc_printbuf_validate(&pb);
2902 }
2903
2904 #define MAX_LINK_STATS_INFO 2000
2905
2906 struct sk_buff *tipc_link_cmd_show_stats(const void *req_tlv_area, int req_tlv_space)
2907 {
2908 struct sk_buff *buf;
2909 struct tlv_desc *rep_tlv;
2910 int str_len;
2911
2912 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_NAME))
2913 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
2914
2915 buf = tipc_cfg_reply_alloc(TLV_SPACE(MAX_LINK_STATS_INFO));
2916 if (!buf)
2917 return NULL;
2918
2919 rep_tlv = (struct tlv_desc *)buf->data;
2920
2921 str_len = tipc_link_stats((char *)TLV_DATA(req_tlv_area),
2922 (char *)TLV_DATA(rep_tlv), MAX_LINK_STATS_INFO);
2923 if (!str_len) {
2924 buf_discard(buf);
2925 return tipc_cfg_reply_error_string("link not found");
2926 }
2927
2928 skb_put(buf, TLV_SPACE(str_len));
2929 TLV_SET(rep_tlv, TIPC_TLV_ULTRA_STRING, NULL, str_len);
2930
2931 return buf;
2932 }
2933
2934 /**
2935 * tipc_link_get_max_pkt - get maximum packet size to use when sending to destination
2936 * @dest: network address of destination node
2937 * @selector: used to select from set of active links
2938 *
2939 * If no active link can be found, uses default maximum packet size.
2940 */
2941
2942 u32 tipc_link_get_max_pkt(u32 dest, u32 selector)
2943 {
2944 struct tipc_node *n_ptr;
2945 struct link *l_ptr;
2946 u32 res = MAX_PKT_DEFAULT;
2947
2948 if (dest == tipc_own_addr)
2949 return MAX_MSG_SIZE;
2950
2951 read_lock_bh(&tipc_net_lock);
2952 n_ptr = tipc_node_find(dest);
2953 if (n_ptr) {
2954 tipc_node_lock(n_ptr);
2955 l_ptr = n_ptr->active_links[selector & 1];
2956 if (l_ptr)
2957 res = l_ptr->max_pkt;
2958 tipc_node_unlock(n_ptr);
2959 }
2960 read_unlock_bh(&tipc_net_lock);
2961 return res;
2962 }
2963
2964 static void link_print(struct link *l_ptr, const char *str)
2965 {
2966 char print_area[256];
2967 struct print_buf pb;
2968 struct print_buf *buf = &pb;
2969
2970 tipc_printbuf_init(buf, print_area, sizeof(print_area));
2971
2972 tipc_printf(buf, str);
2973 tipc_printf(buf, "Link %x<%s>:",
2974 l_ptr->addr, l_ptr->b_ptr->name);
2975
2976 #ifdef CONFIG_TIPC_DEBUG
2977 if (link_reset_reset(l_ptr) || link_reset_unknown(l_ptr))
2978 goto print_state;
2979
2980 tipc_printf(buf, ": NXO(%u):", mod(l_ptr->next_out_no));
2981 tipc_printf(buf, "NXI(%u):", mod(l_ptr->next_in_no));
2982 tipc_printf(buf, "SQUE");
2983 if (l_ptr->first_out) {
2984 tipc_printf(buf, "[%u..", msg_seqno(buf_msg(l_ptr->first_out)));
2985 if (l_ptr->next_out)
2986 tipc_printf(buf, "%u..",
2987 msg_seqno(buf_msg(l_ptr->next_out)));
2988 tipc_printf(buf, "%u]", msg_seqno(buf_msg(l_ptr->last_out)));
2989 if ((mod(msg_seqno(buf_msg(l_ptr->last_out)) -
2990 msg_seqno(buf_msg(l_ptr->first_out)))
2991 != (l_ptr->out_queue_size - 1)) ||
2992 (l_ptr->last_out->next != NULL)) {
2993 tipc_printf(buf, "\nSend queue inconsistency\n");
2994 tipc_printf(buf, "first_out= %p ", l_ptr->first_out);
2995 tipc_printf(buf, "next_out= %p ", l_ptr->next_out);
2996 tipc_printf(buf, "last_out= %p ", l_ptr->last_out);
2997 }
2998 } else
2999 tipc_printf(buf, "[]");
3000 tipc_printf(buf, "SQSIZ(%u)", l_ptr->out_queue_size);
3001 if (l_ptr->oldest_deferred_in) {
3002 u32 o = msg_seqno(buf_msg(l_ptr->oldest_deferred_in));
3003 u32 n = msg_seqno(buf_msg(l_ptr->newest_deferred_in));
3004 tipc_printf(buf, ":RQUE[%u..%u]", o, n);
3005 if (l_ptr->deferred_inqueue_sz != mod((n + 1) - o)) {
3006 tipc_printf(buf, ":RQSIZ(%u)",
3007 l_ptr->deferred_inqueue_sz);
3008 }
3009 }
3010 print_state:
3011 #endif
3012
3013 if (link_working_unknown(l_ptr))
3014 tipc_printf(buf, ":WU");
3015 else if (link_reset_reset(l_ptr))
3016 tipc_printf(buf, ":RR");
3017 else if (link_reset_unknown(l_ptr))
3018 tipc_printf(buf, ":RU");
3019 else if (link_working_working(l_ptr))
3020 tipc_printf(buf, ":WW");
3021 tipc_printf(buf, "\n");
3022
3023 tipc_printbuf_validate(buf);
3024 info("%s", print_area);
3025 }
3026