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USB: convert drivers/media/* to use module_usb_driver()
[zen-stable.git] / net / tipc / link.c
blobae98a72da11a5445a3fb7f4e32ef1258d3abadd5
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, unsigned int total_len,
96 u32 destnode);
97 static void link_check_defragm_bufs(struct link *l_ptr);
98 static void link_state_event(struct link *l_ptr, u32 event);
99 static void link_reset_statistics(struct link *l_ptr);
100 static void link_print(struct link *l_ptr, const char *str);
101 static void link_start(struct link *l_ptr);
102 static int link_send_long_buf(struct link *l_ptr, struct sk_buff *buf);
103
104 /*
105 * Simple link routines
106 */
107
108 static unsigned int align(unsigned int i)
109 {
110 return (i + 3) & ~3u;
111 }
112
113 static void link_init_max_pkt(struct link *l_ptr)
114 {
115 u32 max_pkt;
116
117 max_pkt = (l_ptr->b_ptr->mtu & ~3);
118 if (max_pkt > MAX_MSG_SIZE)
119 max_pkt = MAX_MSG_SIZE;
120
121 l_ptr->max_pkt_target = max_pkt;
122 if (l_ptr->max_pkt_target < MAX_PKT_DEFAULT)
123 l_ptr->max_pkt = l_ptr->max_pkt_target;
124 else
125 l_ptr->max_pkt = MAX_PKT_DEFAULT;
126
127 l_ptr->max_pkt_probes = 0;
128 }
129
130 static u32 link_next_sent(struct link *l_ptr)
131 {
132 if (l_ptr->next_out)
133 return msg_seqno(buf_msg(l_ptr->next_out));
134 return mod(l_ptr->next_out_no);
135 }
136
137 static u32 link_last_sent(struct link *l_ptr)
138 {
139 return mod(link_next_sent(l_ptr) - 1);
140 }
141
142 /*
143 * Simple non-static link routines (i.e. referenced outside this file)
144 */
145
146 int tipc_link_is_up(struct link *l_ptr)
147 {
148 if (!l_ptr)
149 return 0;
150 return link_working_working(l_ptr) || link_working_unknown(l_ptr);
151 }
152
153 int tipc_link_is_active(struct link *l_ptr)
154 {
155 return (l_ptr->owner->active_links[0] == l_ptr) ||
156 (l_ptr->owner->active_links[1] == l_ptr);
157 }
158
159 /**
160 * link_name_validate - validate & (optionally) deconstruct link name
161 * @name - ptr to link name string
162 * @name_parts - ptr to area for link name components (or NULL if not needed)
163 *
164 * Returns 1 if link name is valid, otherwise 0.
165 */
166
167 static int link_name_validate(const char *name, struct link_name *name_parts)
168 {
169 char name_copy[TIPC_MAX_LINK_NAME];
170 char *addr_local;
171 char *if_local;
172 char *addr_peer;
173 char *if_peer;
174 char dummy;
175 u32 z_local, c_local, n_local;
176 u32 z_peer, c_peer, n_peer;
177 u32 if_local_len;
178 u32 if_peer_len;
179
180 /* copy link name & ensure length is OK */
181
182 name_copy[TIPC_MAX_LINK_NAME - 1] = 0;
183 /* need above in case non-Posix strncpy() doesn't pad with nulls */
184 strncpy(name_copy, name, TIPC_MAX_LINK_NAME);
185 if (name_copy[TIPC_MAX_LINK_NAME - 1] != 0)
186 return 0;
187
188 /* ensure all component parts of link name are present */
189
190 addr_local = name_copy;
191 if_local = strchr(addr_local, ':');
192 if (if_local == NULL)
193 return 0;
194 *(if_local++) = 0;
195 addr_peer = strchr(if_local, '-');
196 if (addr_peer == NULL)
197 return 0;
198 *(addr_peer++) = 0;
199 if_local_len = addr_peer - if_local;
200 if_peer = strchr(addr_peer, ':');
201 if (if_peer == NULL)
202 return 0;
203 *(if_peer++) = 0;
204 if_peer_len = strlen(if_peer) + 1;
205
206 /* validate component parts of link name */
207
208 if ((sscanf(addr_local, "%u.%u.%u%c",
209 &z_local, &c_local, &n_local, &dummy) != 3) ||
210 (sscanf(addr_peer, "%u.%u.%u%c",
211 &z_peer, &c_peer, &n_peer, &dummy) != 3) ||
212 (z_local > 255) || (c_local > 4095) || (n_local > 4095) ||
213 (z_peer > 255) || (c_peer > 4095) || (n_peer > 4095) ||
214 (if_local_len <= 1) || (if_local_len > TIPC_MAX_IF_NAME) ||
215 (if_peer_len <= 1) || (if_peer_len > TIPC_MAX_IF_NAME) ||
216 (strspn(if_local, tipc_alphabet) != (if_local_len - 1)) ||
217 (strspn(if_peer, tipc_alphabet) != (if_peer_len - 1)))
218 return 0;
219
220 /* return link name components, if necessary */
221
222 if (name_parts) {
223 name_parts->addr_local = tipc_addr(z_local, c_local, n_local);
224 strcpy(name_parts->if_local, if_local);
225 name_parts->addr_peer = tipc_addr(z_peer, c_peer, n_peer);
226 strcpy(name_parts->if_peer, if_peer);
227 }
228 return 1;
229 }
230
231 /**
232 * link_timeout - handle expiration of link timer
233 * @l_ptr: pointer to link
234 *
235 * This routine must not grab "tipc_net_lock" to avoid a potential deadlock conflict
236 * with tipc_link_delete(). (There is no risk that the node will be deleted by
237 * another thread because tipc_link_delete() always cancels the link timer before
238 * tipc_node_delete() is called.)
239 */
240
241 static void link_timeout(struct link *l_ptr)
242 {
243 tipc_node_lock(l_ptr->owner);
244
245 /* update counters used in statistical profiling of send traffic */
246
247 l_ptr->stats.accu_queue_sz += l_ptr->out_queue_size;
248 l_ptr->stats.queue_sz_counts++;
249
250 if (l_ptr->first_out) {
251 struct tipc_msg *msg = buf_msg(l_ptr->first_out);
252 u32 length = msg_size(msg);
253
254 if ((msg_user(msg) == MSG_FRAGMENTER) &&
255 (msg_type(msg) == FIRST_FRAGMENT)) {
256 length = msg_size(msg_get_wrapped(msg));
257 }
258 if (length) {
259 l_ptr->stats.msg_lengths_total += length;
260 l_ptr->stats.msg_length_counts++;
261 if (length <= 64)
262 l_ptr->stats.msg_length_profile[0]++;
263 else if (length <= 256)
264 l_ptr->stats.msg_length_profile[1]++;
265 else if (length <= 1024)
266 l_ptr->stats.msg_length_profile[2]++;
267 else if (length <= 4096)
268 l_ptr->stats.msg_length_profile[3]++;
269 else if (length <= 16384)
270 l_ptr->stats.msg_length_profile[4]++;
271 else if (length <= 32768)
272 l_ptr->stats.msg_length_profile[5]++;
273 else
274 l_ptr->stats.msg_length_profile[6]++;
275 }
276 }
277
278 /* do all other link processing performed on a periodic basis */
279
280 link_check_defragm_bufs(l_ptr);
281
282 link_state_event(l_ptr, TIMEOUT_EVT);
283
284 if (l_ptr->next_out)
285 tipc_link_push_queue(l_ptr);
286
287 tipc_node_unlock(l_ptr->owner);
288 }
289
290 static void link_set_timer(struct link *l_ptr, u32 time)
291 {
292 k_start_timer(&l_ptr->timer, time);
293 }
294
295 /**
296 * tipc_link_create - create a new link
297 * @n_ptr: pointer to associated node
298 * @b_ptr: pointer to associated bearer
299 * @media_addr: media address to use when sending messages over link
300 *
301 * Returns pointer to link.
302 */
303
304 struct link *tipc_link_create(struct tipc_node *n_ptr,
305 struct tipc_bearer *b_ptr,
306 const struct tipc_media_addr *media_addr)
307 {
308 struct link *l_ptr;
309 struct tipc_msg *msg;
310 char *if_name;
311 char addr_string[16];
312 u32 peer = n_ptr->addr;
313
314 if (n_ptr->link_cnt >= 2) {
315 tipc_addr_string_fill(addr_string, n_ptr->addr);
316 err("Attempt to establish third link to %s\n", addr_string);
317 return NULL;
318 }
319
320 if (n_ptr->links[b_ptr->identity]) {
321 tipc_addr_string_fill(addr_string, n_ptr->addr);
322 err("Attempt to establish second link on <%s> to %s\n",
323 b_ptr->name, addr_string);
324 return NULL;
325 }
326
327 l_ptr = kzalloc(sizeof(*l_ptr), GFP_ATOMIC);
328 if (!l_ptr) {
329 warn("Link creation failed, no memory\n");
330 return NULL;
331 }
332
333 l_ptr->addr = peer;
334 if_name = strchr(b_ptr->name, ':') + 1;
335 sprintf(l_ptr->name, "%u.%u.%u:%s-%u.%u.%u:unknown",
336 tipc_zone(tipc_own_addr), tipc_cluster(tipc_own_addr),
337 tipc_node(tipc_own_addr),
338 if_name,
339 tipc_zone(peer), tipc_cluster(peer), tipc_node(peer));
340 /* note: peer i/f name is updated by reset/activate message */
341 memcpy(&l_ptr->media_addr, media_addr, sizeof(*media_addr));
342 l_ptr->owner = n_ptr;
343 l_ptr->checkpoint = 1;
344 l_ptr->peer_session = INVALID_SESSION;
345 l_ptr->b_ptr = b_ptr;
346 link_set_supervision_props(l_ptr, b_ptr->media->tolerance);
347 l_ptr->state = RESET_UNKNOWN;
348
349 l_ptr->pmsg = (struct tipc_msg *)&l_ptr->proto_msg;
350 msg = l_ptr->pmsg;
351 tipc_msg_init(msg, LINK_PROTOCOL, RESET_MSG, INT_H_SIZE, l_ptr->addr);
352 msg_set_size(msg, sizeof(l_ptr->proto_msg));
353 msg_set_session(msg, (tipc_random & 0xffff));
354 msg_set_bearer_id(msg, b_ptr->identity);
355 strcpy((char *)msg_data(msg), if_name);
356
357 l_ptr->priority = b_ptr->priority;
358 tipc_link_set_queue_limits(l_ptr, b_ptr->media->window);
359
360 link_init_max_pkt(l_ptr);
361
362 l_ptr->next_out_no = 1;
363 INIT_LIST_HEAD(&l_ptr->waiting_ports);
364
365 link_reset_statistics(l_ptr);
366
367 tipc_node_attach_link(n_ptr, l_ptr);
368
369 k_init_timer(&l_ptr->timer, (Handler)link_timeout, (unsigned long)l_ptr);
370 list_add_tail(&l_ptr->link_list, &b_ptr->links);
371 tipc_k_signal((Handler)link_start, (unsigned long)l_ptr);
372
373 return l_ptr;
374 }
375
376 /**
377 * tipc_link_delete - delete a link
378 * @l_ptr: pointer to link
379 *
380 * Note: 'tipc_net_lock' is write_locked, bearer is locked.
381 * This routine must not grab the node lock until after link timer cancellation
382 * to avoid a potential deadlock situation.
383 */
384
385 void tipc_link_delete(struct link *l_ptr)
386 {
387 if (!l_ptr) {
388 err("Attempt to delete non-existent link\n");
389 return;
390 }
391
392 k_cancel_timer(&l_ptr->timer);
393
394 tipc_node_lock(l_ptr->owner);
395 tipc_link_reset(l_ptr);
396 tipc_node_detach_link(l_ptr->owner, l_ptr);
397 tipc_link_stop(l_ptr);
398 list_del_init(&l_ptr->link_list);
399 tipc_node_unlock(l_ptr->owner);
400 k_term_timer(&l_ptr->timer);
401 kfree(l_ptr);
402 }
403
404 static void link_start(struct link *l_ptr)
405 {
406 tipc_node_lock(l_ptr->owner);
407 link_state_event(l_ptr, STARTING_EVT);
408 tipc_node_unlock(l_ptr->owner);
409 }
410
411 /**
412 * link_schedule_port - schedule port for deferred sending
413 * @l_ptr: pointer to link
414 * @origport: reference to sending port
415 * @sz: amount of data to be sent
416 *
417 * Schedules port for renewed sending of messages after link congestion
418 * has abated.
419 */
420
421 static int link_schedule_port(struct link *l_ptr, u32 origport, u32 sz)
422 {
423 struct tipc_port *p_ptr;
424
425 spin_lock_bh(&tipc_port_list_lock);
426 p_ptr = tipc_port_lock(origport);
427 if (p_ptr) {
428 if (!p_ptr->wakeup)
429 goto exit;
430 if (!list_empty(&p_ptr->wait_list))
431 goto exit;
432 p_ptr->congested = 1;
433 p_ptr->waiting_pkts = 1 + ((sz - 1) / l_ptr->max_pkt);
434 list_add_tail(&p_ptr->wait_list, &l_ptr->waiting_ports);
435 l_ptr->stats.link_congs++;
436 exit:
437 tipc_port_unlock(p_ptr);
438 }
439 spin_unlock_bh(&tipc_port_list_lock);
440 return -ELINKCONG;
441 }
442
443 void tipc_link_wakeup_ports(struct link *l_ptr, int all)
444 {
445 struct tipc_port *p_ptr;
446 struct tipc_port *temp_p_ptr;
447 int win = l_ptr->queue_limit[0] - l_ptr->out_queue_size;
448
449 if (all)
450 win = 100000;
451 if (win <= 0)
452 return;
453 if (!spin_trylock_bh(&tipc_port_list_lock))
454 return;
455 if (link_congested(l_ptr))
456 goto exit;
457 list_for_each_entry_safe(p_ptr, temp_p_ptr, &l_ptr->waiting_ports,
458 wait_list) {
459 if (win <= 0)
460 break;
461 list_del_init(&p_ptr->wait_list);
462 spin_lock_bh(p_ptr->lock);
463 p_ptr->congested = 0;
464 p_ptr->wakeup(p_ptr);
465 win -= p_ptr->waiting_pkts;
466 spin_unlock_bh(p_ptr->lock);
467 }
468
469 exit:
470 spin_unlock_bh(&tipc_port_list_lock);
471 }
472
473 /**
474 * link_release_outqueue - purge link's outbound message queue
475 * @l_ptr: pointer to link
476 */
477
478 static void link_release_outqueue(struct link *l_ptr)
479 {
480 struct sk_buff *buf = l_ptr->first_out;
481 struct sk_buff *next;
482
483 while (buf) {
484 next = buf->next;
485 buf_discard(buf);
486 buf = next;
487 }
488 l_ptr->first_out = NULL;
489 l_ptr->out_queue_size = 0;
490 }
491
492 /**
493 * tipc_link_reset_fragments - purge link's inbound message fragments queue
494 * @l_ptr: pointer to link
495 */
496
497 void tipc_link_reset_fragments(struct link *l_ptr)
498 {
499 struct sk_buff *buf = l_ptr->defragm_buf;
500 struct sk_buff *next;
501
502 while (buf) {
503 next = buf->next;
504 buf_discard(buf);
505 buf = next;
506 }
507 l_ptr->defragm_buf = NULL;
508 }
509
510 /**
511 * tipc_link_stop - purge all inbound and outbound messages associated with link
512 * @l_ptr: pointer to link
513 */
514
515 void tipc_link_stop(struct link *l_ptr)
516 {
517 struct sk_buff *buf;
518 struct sk_buff *next;
519
520 buf = l_ptr->oldest_deferred_in;
521 while (buf) {
522 next = buf->next;
523 buf_discard(buf);
524 buf = next;
525 }
526
527 buf = l_ptr->first_out;
528 while (buf) {
529 next = buf->next;
530 buf_discard(buf);
531 buf = next;
532 }
533
534 tipc_link_reset_fragments(l_ptr);
535
536 buf_discard(l_ptr->proto_msg_queue);
537 l_ptr->proto_msg_queue = NULL;
538 }
539
540 void tipc_link_reset(struct link *l_ptr)
541 {
542 struct sk_buff *buf;
543 u32 prev_state = l_ptr->state;
544 u32 checkpoint = l_ptr->next_in_no;
545 int was_active_link = tipc_link_is_active(l_ptr);
546
547 msg_set_session(l_ptr->pmsg, ((msg_session(l_ptr->pmsg) + 1) & 0xffff));
548
549 /* Link is down, accept any session */
550 l_ptr->peer_session = INVALID_SESSION;
551
552 /* Prepare for max packet size negotiation */
553 link_init_max_pkt(l_ptr);
554
555 l_ptr->state = RESET_UNKNOWN;
556
557 if ((prev_state == RESET_UNKNOWN) || (prev_state == RESET_RESET))
558 return;
559
560 tipc_node_link_down(l_ptr->owner, l_ptr);
561 tipc_bearer_remove_dest(l_ptr->b_ptr, l_ptr->addr);
562
563 if (was_active_link && tipc_node_active_links(l_ptr->owner) &&
564 l_ptr->owner->permit_changeover) {
565 l_ptr->reset_checkpoint = checkpoint;
566 l_ptr->exp_msg_count = START_CHANGEOVER;
567 }
568
569 /* Clean up all queues: */
570
571 link_release_outqueue(l_ptr);
572 buf_discard(l_ptr->proto_msg_queue);
573 l_ptr->proto_msg_queue = NULL;
574 buf = l_ptr->oldest_deferred_in;
575 while (buf) {
576 struct sk_buff *next = buf->next;
577 buf_discard(buf);
578 buf = next;
579 }
580 if (!list_empty(&l_ptr->waiting_ports))
581 tipc_link_wakeup_ports(l_ptr, 1);
582
583 l_ptr->retransm_queue_head = 0;
584 l_ptr->retransm_queue_size = 0;
585 l_ptr->last_out = NULL;
586 l_ptr->first_out = NULL;
587 l_ptr->next_out = NULL;
588 l_ptr->unacked_window = 0;
589 l_ptr->checkpoint = 1;
590 l_ptr->next_out_no = 1;
591 l_ptr->deferred_inqueue_sz = 0;
592 l_ptr->oldest_deferred_in = NULL;
593 l_ptr->newest_deferred_in = NULL;
594 l_ptr->fsm_msg_cnt = 0;
595 l_ptr->stale_count = 0;
596 link_reset_statistics(l_ptr);
597 }
598
599
600 static void link_activate(struct link *l_ptr)
601 {
602 l_ptr->next_in_no = l_ptr->stats.recv_info = 1;
603 tipc_node_link_up(l_ptr->owner, l_ptr);
604 tipc_bearer_add_dest(l_ptr->b_ptr, l_ptr->addr);
605 }
606
607 /**
608 * link_state_event - link finite state machine
609 * @l_ptr: pointer to link
610 * @event: state machine event to process
611 */
612
613 static void link_state_event(struct link *l_ptr, unsigned event)
614 {
615 struct link *other;
616 u32 cont_intv = l_ptr->continuity_interval;
617
618 if (!l_ptr->started && (event != STARTING_EVT))
619 return; /* Not yet. */
620
621 if (link_blocked(l_ptr)) {
622 if (event == TIMEOUT_EVT)
623 link_set_timer(l_ptr, cont_intv);
624 return; /* Changeover going on */
625 }
626
627 switch (l_ptr->state) {
628 case WORKING_WORKING:
629 switch (event) {
630 case TRAFFIC_MSG_EVT:
631 case ACTIVATE_MSG:
632 break;
633 case TIMEOUT_EVT:
634 if (l_ptr->next_in_no != l_ptr->checkpoint) {
635 l_ptr->checkpoint = l_ptr->next_in_no;
636 if (tipc_bclink_acks_missing(l_ptr->owner)) {
637 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
638 0, 0, 0, 0, 0);
639 l_ptr->fsm_msg_cnt++;
640 } else if (l_ptr->max_pkt < l_ptr->max_pkt_target) {
641 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
642 1, 0, 0, 0, 0);
643 l_ptr->fsm_msg_cnt++;
644 }
645 link_set_timer(l_ptr, cont_intv);
646 break;
647 }
648 l_ptr->state = WORKING_UNKNOWN;
649 l_ptr->fsm_msg_cnt = 0;
650 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
651 l_ptr->fsm_msg_cnt++;
652 link_set_timer(l_ptr, cont_intv / 4);
653 break;
654 case RESET_MSG:
655 info("Resetting link <%s>, requested by peer\n",
656 l_ptr->name);
657 tipc_link_reset(l_ptr);
658 l_ptr->state = RESET_RESET;
659 l_ptr->fsm_msg_cnt = 0;
660 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0);
661 l_ptr->fsm_msg_cnt++;
662 link_set_timer(l_ptr, cont_intv);
663 break;
664 default:
665 err("Unknown link event %u in WW state\n", event);
666 }
667 break;
668 case WORKING_UNKNOWN:
669 switch (event) {
670 case TRAFFIC_MSG_EVT:
671 case ACTIVATE_MSG:
672 l_ptr->state = WORKING_WORKING;
673 l_ptr->fsm_msg_cnt = 0;
674 link_set_timer(l_ptr, cont_intv);
675 break;
676 case RESET_MSG:
677 info("Resetting link <%s>, requested by peer "
678 "while probing\n", l_ptr->name);
679 tipc_link_reset(l_ptr);
680 l_ptr->state = RESET_RESET;
681 l_ptr->fsm_msg_cnt = 0;
682 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0);
683 l_ptr->fsm_msg_cnt++;
684 link_set_timer(l_ptr, cont_intv);
685 break;
686 case TIMEOUT_EVT:
687 if (l_ptr->next_in_no != l_ptr->checkpoint) {
688 l_ptr->state = WORKING_WORKING;
689 l_ptr->fsm_msg_cnt = 0;
690 l_ptr->checkpoint = l_ptr->next_in_no;
691 if (tipc_bclink_acks_missing(l_ptr->owner)) {
692 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
693 0, 0, 0, 0, 0);
694 l_ptr->fsm_msg_cnt++;
695 }
696 link_set_timer(l_ptr, cont_intv);
697 } else if (l_ptr->fsm_msg_cnt < l_ptr->abort_limit) {
698 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
699 1, 0, 0, 0, 0);
700 l_ptr->fsm_msg_cnt++;
701 link_set_timer(l_ptr, cont_intv / 4);
702 } else { /* Link has failed */
703 warn("Resetting link <%s>, peer not responding\n",
704 l_ptr->name);
705 tipc_link_reset(l_ptr);
706 l_ptr->state = RESET_UNKNOWN;
707 l_ptr->fsm_msg_cnt = 0;
708 tipc_link_send_proto_msg(l_ptr, RESET_MSG,
709 0, 0, 0, 0, 0);
710 l_ptr->fsm_msg_cnt++;
711 link_set_timer(l_ptr, cont_intv);
712 }
713 break;
714 default:
715 err("Unknown link event %u in WU state\n", event);
716 }
717 break;
718 case RESET_UNKNOWN:
719 switch (event) {
720 case TRAFFIC_MSG_EVT:
721 break;
722 case ACTIVATE_MSG:
723 other = l_ptr->owner->active_links[0];
724 if (other && link_working_unknown(other))
725 break;
726 l_ptr->state = WORKING_WORKING;
727 l_ptr->fsm_msg_cnt = 0;
728 link_activate(l_ptr);
729 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
730 l_ptr->fsm_msg_cnt++;
731 link_set_timer(l_ptr, cont_intv);
732 break;
733 case RESET_MSG:
734 l_ptr->state = RESET_RESET;
735 l_ptr->fsm_msg_cnt = 0;
736 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 1, 0, 0, 0, 0);
737 l_ptr->fsm_msg_cnt++;
738 link_set_timer(l_ptr, cont_intv);
739 break;
740 case STARTING_EVT:
741 l_ptr->started = 1;
742 /* fall through */
743 case TIMEOUT_EVT:
744 tipc_link_send_proto_msg(l_ptr, RESET_MSG, 0, 0, 0, 0, 0);
745 l_ptr->fsm_msg_cnt++;
746 link_set_timer(l_ptr, cont_intv);
747 break;
748 default:
749 err("Unknown link event %u in RU state\n", event);
750 }
751 break;
752 case RESET_RESET:
753 switch (event) {
754 case TRAFFIC_MSG_EVT:
755 case ACTIVATE_MSG:
756 other = l_ptr->owner->active_links[0];
757 if (other && link_working_unknown(other))
758 break;
759 l_ptr->state = WORKING_WORKING;
760 l_ptr->fsm_msg_cnt = 0;
761 link_activate(l_ptr);
762 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
763 l_ptr->fsm_msg_cnt++;
764 link_set_timer(l_ptr, cont_intv);
765 break;
766 case RESET_MSG:
767 break;
768 case TIMEOUT_EVT:
769 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0);
770 l_ptr->fsm_msg_cnt++;
771 link_set_timer(l_ptr, cont_intv);
772 break;
773 default:
774 err("Unknown link event %u in RR state\n", event);
775 }
776 break;
777 default:
778 err("Unknown link state %u/%u\n", l_ptr->state, event);
779 }
780 }
781
782 /*
783 * link_bundle_buf(): Append contents of a buffer to
784 * the tail of an existing one.
785 */
786
787 static int link_bundle_buf(struct link *l_ptr,
788 struct sk_buff *bundler,
789 struct sk_buff *buf)
790 {
791 struct tipc_msg *bundler_msg = buf_msg(bundler);
792 struct tipc_msg *msg = buf_msg(buf);
793 u32 size = msg_size(msg);
794 u32 bundle_size = msg_size(bundler_msg);
795 u32 to_pos = align(bundle_size);
796 u32 pad = to_pos - bundle_size;
797
798 if (msg_user(bundler_msg) != MSG_BUNDLER)
799 return 0;
800 if (msg_type(bundler_msg) != OPEN_MSG)
801 return 0;
802 if (skb_tailroom(bundler) < (pad + size))
803 return 0;
804 if (l_ptr->max_pkt < (to_pos + size))
805 return 0;
806
807 skb_put(bundler, pad + size);
808 skb_copy_to_linear_data_offset(bundler, to_pos, buf->data, size);
809 msg_set_size(bundler_msg, to_pos + size);
810 msg_set_msgcnt(bundler_msg, msg_msgcnt(bundler_msg) + 1);
811 buf_discard(buf);
812 l_ptr->stats.sent_bundled++;
813 return 1;
814 }
815
816 static void link_add_to_outqueue(struct link *l_ptr,
817 struct sk_buff *buf,
818 struct tipc_msg *msg)
819 {
820 u32 ack = mod(l_ptr->next_in_no - 1);
821 u32 seqno = mod(l_ptr->next_out_no++);
822
823 msg_set_word(msg, 2, ((ack << 16) | seqno));
824 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
825 buf->next = NULL;
826 if (l_ptr->first_out) {
827 l_ptr->last_out->next = buf;
828 l_ptr->last_out = buf;
829 } else
830 l_ptr->first_out = l_ptr->last_out = buf;
831
832 l_ptr->out_queue_size++;
833 if (l_ptr->out_queue_size > l_ptr->stats.max_queue_sz)
834 l_ptr->stats.max_queue_sz = l_ptr->out_queue_size;
835 }
836
837 static void link_add_chain_to_outqueue(struct link *l_ptr,
838 struct sk_buff *buf_chain,
839 u32 long_msgno)
840 {
841 struct sk_buff *buf;
842 struct tipc_msg *msg;
843
844 if (!l_ptr->next_out)
845 l_ptr->next_out = buf_chain;
846 while (buf_chain) {
847 buf = buf_chain;
848 buf_chain = buf_chain->next;
849
850 msg = buf_msg(buf);
851 msg_set_long_msgno(msg, long_msgno);
852 link_add_to_outqueue(l_ptr, buf, msg);
853 }
854 }
855
856 /*
857 * tipc_link_send_buf() is the 'full path' for messages, called from
858 * inside TIPC when the 'fast path' in tipc_send_buf
859 * has failed, and from link_send()
860 */
861
862 int tipc_link_send_buf(struct link *l_ptr, struct sk_buff *buf)
863 {
864 struct tipc_msg *msg = buf_msg(buf);
865 u32 size = msg_size(msg);
866 u32 dsz = msg_data_sz(msg);
867 u32 queue_size = l_ptr->out_queue_size;
868 u32 imp = tipc_msg_tot_importance(msg);
869 u32 queue_limit = l_ptr->queue_limit[imp];
870 u32 max_packet = l_ptr->max_pkt;
871
872 msg_set_prevnode(msg, tipc_own_addr); /* If routed message */
873
874 /* Match msg importance against queue limits: */
875
876 if (unlikely(queue_size >= queue_limit)) {
877 if (imp <= TIPC_CRITICAL_IMPORTANCE) {
878 link_schedule_port(l_ptr, msg_origport(msg), size);
879 buf_discard(buf);
880 return -ELINKCONG;
881 }
882 buf_discard(buf);
883 if (imp > CONN_MANAGER) {
884 warn("Resetting link <%s>, send queue full", l_ptr->name);
885 tipc_link_reset(l_ptr);
886 }
887 return dsz;
888 }
889
890 /* Fragmentation needed ? */
891
892 if (size > max_packet)
893 return link_send_long_buf(l_ptr, buf);
894
895 /* Packet can be queued or sent: */
896
897 if (likely(!tipc_bearer_congested(l_ptr->b_ptr, l_ptr) &&
898 !link_congested(l_ptr))) {
899 link_add_to_outqueue(l_ptr, buf, msg);
900
901 if (likely(tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr))) {
902 l_ptr->unacked_window = 0;
903 } else {
904 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr);
905 l_ptr->stats.bearer_congs++;
906 l_ptr->next_out = buf;
907 }
908 return dsz;
909 }
910 /* Congestion: can message be bundled ?: */
911
912 if ((msg_user(msg) != CHANGEOVER_PROTOCOL) &&
913 (msg_user(msg) != MSG_FRAGMENTER)) {
914
915 /* Try adding message to an existing bundle */
916
917 if (l_ptr->next_out &&
918 link_bundle_buf(l_ptr, l_ptr->last_out, buf)) {
919 tipc_bearer_resolve_congestion(l_ptr->b_ptr, l_ptr);
920 return dsz;
921 }
922
923 /* Try creating a new bundle */
924
925 if (size <= max_packet * 2 / 3) {
926 struct sk_buff *bundler = tipc_buf_acquire(max_packet);
927 struct tipc_msg bundler_hdr;
928
929 if (bundler) {
930 tipc_msg_init(&bundler_hdr, MSG_BUNDLER, OPEN_MSG,
931 INT_H_SIZE, l_ptr->addr);
932 skb_copy_to_linear_data(bundler, &bundler_hdr,
933 INT_H_SIZE);
934 skb_trim(bundler, INT_H_SIZE);
935 link_bundle_buf(l_ptr, bundler, buf);
936 buf = bundler;
937 msg = buf_msg(buf);
938 l_ptr->stats.sent_bundles++;
939 }
940 }
941 }
942 if (!l_ptr->next_out)
943 l_ptr->next_out = buf;
944 link_add_to_outqueue(l_ptr, buf, msg);
945 tipc_bearer_resolve_congestion(l_ptr->b_ptr, l_ptr);
946 return dsz;
947 }
948
949 /*
950 * tipc_link_send(): same as tipc_link_send_buf(), but the link to use has
951 * not been selected yet, and the the owner node is not locked
952 * Called by TIPC internal users, e.g. the name distributor
953 */
954
955 int tipc_link_send(struct sk_buff *buf, u32 dest, u32 selector)
956 {
957 struct link *l_ptr;
958 struct tipc_node *n_ptr;
959 int res = -ELINKCONG;
960
961 read_lock_bh(&tipc_net_lock);
962 n_ptr = tipc_node_find(dest);
963 if (n_ptr) {
964 tipc_node_lock(n_ptr);
965 l_ptr = n_ptr->active_links[selector & 1];
966 if (l_ptr)
967 res = tipc_link_send_buf(l_ptr, buf);
968 else
969 buf_discard(buf);
970 tipc_node_unlock(n_ptr);
971 } else {
972 buf_discard(buf);
973 }
974 read_unlock_bh(&tipc_net_lock);
975 return res;
976 }
977
978 /*
979 * tipc_link_send_names - send name table entries to new neighbor
980 *
981 * Send routine for bulk delivery of name table messages when contact
982 * with a new neighbor occurs. No link congestion checking is performed
983 * because name table messages *must* be delivered. The messages must be
984 * small enough not to require fragmentation.
985 * Called without any locks held.
986 */
987
988 void tipc_link_send_names(struct list_head *message_list, u32 dest)
989 {
990 struct tipc_node *n_ptr;
991 struct link *l_ptr;
992 struct sk_buff *buf;
993 struct sk_buff *temp_buf;
994
995 if (list_empty(message_list))
996 return;
997
998 read_lock_bh(&tipc_net_lock);
999 n_ptr = tipc_node_find(dest);
1000 if (n_ptr) {
1001 tipc_node_lock(n_ptr);
1002 l_ptr = n_ptr->active_links[0];
1003 if (l_ptr) {
1004 /* convert circular list to linear list */
1005 ((struct sk_buff *)message_list->prev)->next = NULL;
1006 link_add_chain_to_outqueue(l_ptr,
1007 (struct sk_buff *)message_list->next, 0);
1008 tipc_link_push_queue(l_ptr);
1009 INIT_LIST_HEAD(message_list);
1010 }
1011 tipc_node_unlock(n_ptr);
1012 }
1013 read_unlock_bh(&tipc_net_lock);
1014
1015 /* discard the messages if they couldn't be sent */
1016
1017 list_for_each_safe(buf, temp_buf, ((struct sk_buff *)message_list)) {
1018 list_del((struct list_head *)buf);
1019 buf_discard(buf);
1020 }
1021 }
1022
1023 /*
1024 * link_send_buf_fast: Entry for data messages where the
1025 * destination link is known and the header is complete,
1026 * inclusive total message length. Very time critical.
1027 * Link is locked. Returns user data length.
1028 */
1029
1030 static int link_send_buf_fast(struct link *l_ptr, struct sk_buff *buf,
1031 u32 *used_max_pkt)
1032 {
1033 struct tipc_msg *msg = buf_msg(buf);
1034 int res = msg_data_sz(msg);
1035
1036 if (likely(!link_congested(l_ptr))) {
1037 if (likely(msg_size(msg) <= l_ptr->max_pkt)) {
1038 if (likely(list_empty(&l_ptr->b_ptr->cong_links))) {
1039 link_add_to_outqueue(l_ptr, buf, msg);
1040 if (likely(tipc_bearer_send(l_ptr->b_ptr, buf,
1041 &l_ptr->media_addr))) {
1042 l_ptr->unacked_window = 0;
1043 return res;
1044 }
1045 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr);
1046 l_ptr->stats.bearer_congs++;
1047 l_ptr->next_out = buf;
1048 return res;
1049 }
1050 } else
1051 *used_max_pkt = l_ptr->max_pkt;
1052 }
1053 return tipc_link_send_buf(l_ptr, buf); /* All other cases */
1054 }
1055
1056 /*
1057 * tipc_send_buf_fast: Entry for data messages where the
1058 * destination node is known and the header is complete,
1059 * inclusive total message length.
1060 * Returns user data length.
1061 */
1062 int tipc_send_buf_fast(struct sk_buff *buf, u32 destnode)
1063 {
1064 struct link *l_ptr;
1065 struct tipc_node *n_ptr;
1066 int res;
1067 u32 selector = msg_origport(buf_msg(buf)) & 1;
1068 u32 dummy;
1069
1070 read_lock_bh(&tipc_net_lock);
1071 n_ptr = tipc_node_find(destnode);
1072 if (likely(n_ptr)) {
1073 tipc_node_lock(n_ptr);
1074 l_ptr = n_ptr->active_links[selector];
1075 if (likely(l_ptr)) {
1076 res = link_send_buf_fast(l_ptr, buf, &dummy);
1077 tipc_node_unlock(n_ptr);
1078 read_unlock_bh(&tipc_net_lock);
1079 return res;
1080 }
1081 tipc_node_unlock(n_ptr);
1082 }
1083 read_unlock_bh(&tipc_net_lock);
1084 res = msg_data_sz(buf_msg(buf));
1085 tipc_reject_msg(buf, TIPC_ERR_NO_NODE);
1086 return res;
1087 }
1088
1089
1090 /*
1091 * tipc_link_send_sections_fast: Entry for messages where the
1092 * destination processor is known and the header is complete,
1093 * except for total message length.
1094 * Returns user data length or errno.
1095 */
1096 int tipc_link_send_sections_fast(struct tipc_port *sender,
1097 struct iovec const *msg_sect,
1098 const u32 num_sect,
1099 unsigned int total_len,
1100 u32 destaddr)
1101 {
1102 struct tipc_msg *hdr = &sender->phdr;
1103 struct link *l_ptr;
1104 struct sk_buff *buf;
1105 struct tipc_node *node;
1106 int res;
1107 u32 selector = msg_origport(hdr) & 1;
1108
1109 again:
1110 /*
1111 * Try building message using port's max_pkt hint.
1112 * (Must not hold any locks while building message.)
1113 */
1114
1115 res = tipc_msg_build(hdr, msg_sect, num_sect, total_len,
1116 sender->max_pkt, !sender->user_port, &buf);
1117
1118 read_lock_bh(&tipc_net_lock);
1119 node = tipc_node_find(destaddr);
1120 if (likely(node)) {
1121 tipc_node_lock(node);
1122 l_ptr = node->active_links[selector];
1123 if (likely(l_ptr)) {
1124 if (likely(buf)) {
1125 res = link_send_buf_fast(l_ptr, buf,
1126 &sender->max_pkt);
1127 exit:
1128 tipc_node_unlock(node);
1129 read_unlock_bh(&tipc_net_lock);
1130 return res;
1131 }
1132
1133 /* Exit if build request was invalid */
1134
1135 if (unlikely(res < 0))
1136 goto exit;
1137
1138 /* Exit if link (or bearer) is congested */
1139
1140 if (link_congested(l_ptr) ||
1141 !list_empty(&l_ptr->b_ptr->cong_links)) {
1142 res = link_schedule_port(l_ptr,
1143 sender->ref, res);
1144 goto exit;
1145 }
1146
1147 /*
1148 * Message size exceeds max_pkt hint; update hint,
1149 * then re-try fast path or fragment the message
1150 */
1151
1152 sender->max_pkt = l_ptr->max_pkt;
1153 tipc_node_unlock(node);
1154 read_unlock_bh(&tipc_net_lock);
1155
1156
1157 if ((msg_hdr_sz(hdr) + res) <= sender->max_pkt)
1158 goto again;
1159
1160 return link_send_sections_long(sender, msg_sect,
1161 num_sect, total_len,
1162 destaddr);
1163 }
1164 tipc_node_unlock(node);
1165 }
1166 read_unlock_bh(&tipc_net_lock);
1167
1168 /* Couldn't find a link to the destination node */
1169
1170 if (buf)
1171 return tipc_reject_msg(buf, TIPC_ERR_NO_NODE);
1172 if (res >= 0)
1173 return tipc_port_reject_sections(sender, hdr, msg_sect, num_sect,
1174 total_len, TIPC_ERR_NO_NODE);
1175 return res;
1176 }
1177
1178 /*
1179 * link_send_sections_long(): Entry for long messages where the
1180 * destination node is known and the header is complete,
1181 * inclusive total message length.
1182 * Link and bearer congestion status have been checked to be ok,
1183 * and are ignored if they change.
1184 *
1185 * Note that fragments do not use the full link MTU so that they won't have
1186 * to undergo refragmentation if link changeover causes them to be sent
1187 * over another link with an additional tunnel header added as prefix.
1188 * (Refragmentation will still occur if the other link has a smaller MTU.)
1189 *
1190 * Returns user data length or errno.
1191 */
1192 static int link_send_sections_long(struct tipc_port *sender,
1193 struct iovec const *msg_sect,
1194 u32 num_sect,
1195 unsigned int total_len,
1196 u32 destaddr)
1197 {
1198 struct link *l_ptr;
1199 struct tipc_node *node;
1200 struct tipc_msg *hdr = &sender->phdr;
1201 u32 dsz = total_len;
1202 u32 max_pkt, fragm_sz, rest;
1203 struct tipc_msg fragm_hdr;
1204 struct sk_buff *buf, *buf_chain, *prev;
1205 u32 fragm_crs, fragm_rest, hsz, sect_rest;
1206 const unchar *sect_crs;
1207 int curr_sect;
1208 u32 fragm_no;
1209
1210 again:
1211 fragm_no = 1;
1212 max_pkt = sender->max_pkt - INT_H_SIZE;
1213 /* leave room for tunnel header in case of link changeover */
1214 fragm_sz = max_pkt - INT_H_SIZE;
1215 /* leave room for fragmentation header in each fragment */
1216 rest = dsz;
1217 fragm_crs = 0;
1218 fragm_rest = 0;
1219 sect_rest = 0;
1220 sect_crs = NULL;
1221 curr_sect = -1;
1222
1223 /* Prepare reusable fragment header: */
1224
1225 tipc_msg_init(&fragm_hdr, MSG_FRAGMENTER, FIRST_FRAGMENT,
1226 INT_H_SIZE, msg_destnode(hdr));
1227 msg_set_size(&fragm_hdr, max_pkt);
1228 msg_set_fragm_no(&fragm_hdr, 1);
1229
1230 /* Prepare header of first fragment: */
1231
1232 buf_chain = buf = tipc_buf_acquire(max_pkt);
1233 if (!buf)
1234 return -ENOMEM;
1235 buf->next = NULL;
1236 skb_copy_to_linear_data(buf, &fragm_hdr, INT_H_SIZE);
1237 hsz = msg_hdr_sz(hdr);
1238 skb_copy_to_linear_data_offset(buf, INT_H_SIZE, hdr, hsz);
1239
1240 /* Chop up message: */
1241
1242 fragm_crs = INT_H_SIZE + hsz;
1243 fragm_rest = fragm_sz - hsz;
1244
1245 do { /* For all sections */
1246 u32 sz;
1247
1248 if (!sect_rest) {
1249 sect_rest = msg_sect[++curr_sect].iov_len;
1250 sect_crs = (const unchar *)msg_sect[curr_sect].iov_base;
1251 }
1252
1253 if (sect_rest < fragm_rest)
1254 sz = sect_rest;
1255 else
1256 sz = fragm_rest;
1257
1258 if (likely(!sender->user_port)) {
1259 if (copy_from_user(buf->data + fragm_crs, sect_crs, sz)) {
1260 error:
1261 for (; buf_chain; buf_chain = buf) {
1262 buf = buf_chain->next;
1263 buf_discard(buf_chain);
1264 }
1265 return -EFAULT;
1266 }
1267 } else
1268 skb_copy_to_linear_data_offset(buf, fragm_crs,
1269 sect_crs, sz);
1270 sect_crs += sz;
1271 sect_rest -= sz;
1272 fragm_crs += sz;
1273 fragm_rest -= sz;
1274 rest -= sz;
1275
1276 if (!fragm_rest && rest) {
1277
1278 /* Initiate new fragment: */
1279 if (rest <= fragm_sz) {
1280 fragm_sz = rest;
1281 msg_set_type(&fragm_hdr, LAST_FRAGMENT);
1282 } else {
1283 msg_set_type(&fragm_hdr, FRAGMENT);
1284 }
1285 msg_set_size(&fragm_hdr, fragm_sz + INT_H_SIZE);
1286 msg_set_fragm_no(&fragm_hdr, ++fragm_no);
1287 prev = buf;
1288 buf = tipc_buf_acquire(fragm_sz + INT_H_SIZE);
1289 if (!buf)
1290 goto error;
1291
1292 buf->next = NULL;
1293 prev->next = buf;
1294 skb_copy_to_linear_data(buf, &fragm_hdr, INT_H_SIZE);
1295 fragm_crs = INT_H_SIZE;
1296 fragm_rest = fragm_sz;
1297 }
1298 } while (rest > 0);
1299
1300 /*
1301 * Now we have a buffer chain. Select a link and check
1302 * that packet size is still OK
1303 */
1304 node = tipc_node_find(destaddr);
1305 if (likely(node)) {
1306 tipc_node_lock(node);
1307 l_ptr = node->active_links[sender->ref & 1];
1308 if (!l_ptr) {
1309 tipc_node_unlock(node);
1310 goto reject;
1311 }
1312 if (l_ptr->max_pkt < max_pkt) {
1313 sender->max_pkt = l_ptr->max_pkt;
1314 tipc_node_unlock(node);
1315 for (; buf_chain; buf_chain = buf) {
1316 buf = buf_chain->next;
1317 buf_discard(buf_chain);
1318 }
1319 goto again;
1320 }
1321 } else {
1322 reject:
1323 for (; buf_chain; buf_chain = buf) {
1324 buf = buf_chain->next;
1325 buf_discard(buf_chain);
1326 }
1327 return tipc_port_reject_sections(sender, hdr, msg_sect, num_sect,
1328 total_len, TIPC_ERR_NO_NODE);
1329 }
1330
1331 /* Append chain of fragments to send queue & send them */
1332
1333 l_ptr->long_msg_seq_no++;
1334 link_add_chain_to_outqueue(l_ptr, buf_chain, l_ptr->long_msg_seq_no);
1335 l_ptr->stats.sent_fragments += fragm_no;
1336 l_ptr->stats.sent_fragmented++;
1337 tipc_link_push_queue(l_ptr);
1338 tipc_node_unlock(node);
1339 return dsz;
1340 }
1341
1342 /*
1343 * tipc_link_push_packet: Push one unsent packet to the media
1344 */
1345 u32 tipc_link_push_packet(struct link *l_ptr)
1346 {
1347 struct sk_buff *buf = l_ptr->first_out;
1348 u32 r_q_size = l_ptr->retransm_queue_size;
1349 u32 r_q_head = l_ptr->retransm_queue_head;
1350
1351 /* Step to position where retransmission failed, if any, */
1352 /* consider that buffers may have been released in meantime */
1353
1354 if (r_q_size && buf) {
1355 u32 last = lesser(mod(r_q_head + r_q_size),
1356 link_last_sent(l_ptr));
1357 u32 first = msg_seqno(buf_msg(buf));
1358
1359 while (buf && less(first, r_q_head)) {
1360 first = mod(first + 1);
1361 buf = buf->next;
1362 }
1363 l_ptr->retransm_queue_head = r_q_head = first;
1364 l_ptr->retransm_queue_size = r_q_size = mod(last - first);
1365 }
1366
1367 /* Continue retransmission now, if there is anything: */
1368
1369 if (r_q_size && buf) {
1370 msg_set_ack(buf_msg(buf), mod(l_ptr->next_in_no - 1));
1371 msg_set_bcast_ack(buf_msg(buf), l_ptr->owner->bclink.last_in);
1372 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) {
1373 l_ptr->retransm_queue_head = mod(++r_q_head);
1374 l_ptr->retransm_queue_size = --r_q_size;
1375 l_ptr->stats.retransmitted++;
1376 return 0;
1377 } else {
1378 l_ptr->stats.bearer_congs++;
1379 return PUSH_FAILED;
1380 }
1381 }
1382
1383 /* Send deferred protocol message, if any: */
1384
1385 buf = l_ptr->proto_msg_queue;
1386 if (buf) {
1387 msg_set_ack(buf_msg(buf), mod(l_ptr->next_in_no - 1));
1388 msg_set_bcast_ack(buf_msg(buf), l_ptr->owner->bclink.last_in);
1389 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) {
1390 l_ptr->unacked_window = 0;
1391 buf_discard(buf);
1392 l_ptr->proto_msg_queue = NULL;
1393 return 0;
1394 } else {
1395 l_ptr->stats.bearer_congs++;
1396 return PUSH_FAILED;
1397 }
1398 }
1399
1400 /* Send one deferred data message, if send window not full: */
1401
1402 buf = l_ptr->next_out;
1403 if (buf) {
1404 struct tipc_msg *msg = buf_msg(buf);
1405 u32 next = msg_seqno(msg);
1406 u32 first = msg_seqno(buf_msg(l_ptr->first_out));
1407
1408 if (mod(next - first) < l_ptr->queue_limit[0]) {
1409 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
1410 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1411 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) {
1412 if (msg_user(msg) == MSG_BUNDLER)
1413 msg_set_type(msg, CLOSED_MSG);
1414 l_ptr->next_out = buf->next;
1415 return 0;
1416 } else {
1417 l_ptr->stats.bearer_congs++;
1418 return PUSH_FAILED;
1419 }
1420 }
1421 }
1422 return PUSH_FINISHED;
1423 }
1424
1425 /*
1426 * push_queue(): push out the unsent messages of a link where
1427 * congestion has abated. Node is locked
1428 */
1429 void tipc_link_push_queue(struct link *l_ptr)
1430 {
1431 u32 res;
1432
1433 if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr))
1434 return;
1435
1436 do {
1437 res = tipc_link_push_packet(l_ptr);
1438 } while (!res);
1439
1440 if (res == PUSH_FAILED)
1441 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr);
1442 }
1443
1444 static void link_reset_all(unsigned long addr)
1445 {
1446 struct tipc_node *n_ptr;
1447 char addr_string[16];
1448 u32 i;
1449
1450 read_lock_bh(&tipc_net_lock);
1451 n_ptr = tipc_node_find((u32)addr);
1452 if (!n_ptr) {
1453 read_unlock_bh(&tipc_net_lock);
1454 return; /* node no longer exists */
1455 }
1456
1457 tipc_node_lock(n_ptr);
1458
1459 warn("Resetting all links to %s\n",
1460 tipc_addr_string_fill(addr_string, n_ptr->addr));
1461
1462 for (i = 0; i < MAX_BEARERS; i++) {
1463 if (n_ptr->links[i]) {
1464 link_print(n_ptr->links[i], "Resetting link\n");
1465 tipc_link_reset(n_ptr->links[i]);
1466 }
1467 }
1468
1469 tipc_node_unlock(n_ptr);
1470 read_unlock_bh(&tipc_net_lock);
1471 }
1472
1473 static void link_retransmit_failure(struct link *l_ptr, struct sk_buff *buf)
1474 {
1475 struct tipc_msg *msg = buf_msg(buf);
1476
1477 warn("Retransmission failure on link <%s>\n", l_ptr->name);
1478
1479 if (l_ptr->addr) {
1480
1481 /* Handle failure on standard link */
1482
1483 link_print(l_ptr, "Resetting link\n");
1484 tipc_link_reset(l_ptr);
1485
1486 } else {
1487
1488 /* Handle failure on broadcast link */
1489
1490 struct tipc_node *n_ptr;
1491 char addr_string[16];
1492
1493 info("Msg seq number: %u, ", msg_seqno(msg));
1494 info("Outstanding acks: %lu\n",
1495 (unsigned long) TIPC_SKB_CB(buf)->handle);
1496
1497 n_ptr = tipc_bclink_retransmit_to();
1498 tipc_node_lock(n_ptr);
1499
1500 tipc_addr_string_fill(addr_string, n_ptr->addr);
1501 info("Multicast link info for %s\n", addr_string);
1502 info("Supported: %d, ", n_ptr->bclink.supported);
1503 info("Acked: %u\n", n_ptr->bclink.acked);
1504 info("Last in: %u, ", n_ptr->bclink.last_in);
1505 info("Gap after: %u, ", n_ptr->bclink.gap_after);
1506 info("Gap to: %u\n", n_ptr->bclink.gap_to);
1507 info("Nack sync: %u\n\n", n_ptr->bclink.nack_sync);
1508
1509 tipc_k_signal((Handler)link_reset_all, (unsigned long)n_ptr->addr);
1510
1511 tipc_node_unlock(n_ptr);
1512
1513 l_ptr->stale_count = 0;
1514 }
1515 }
1516
1517 void tipc_link_retransmit(struct link *l_ptr, struct sk_buff *buf,
1518 u32 retransmits)
1519 {
1520 struct tipc_msg *msg;
1521
1522 if (!buf)
1523 return;
1524
1525 msg = buf_msg(buf);
1526
1527 if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr)) {
1528 if (l_ptr->retransm_queue_size == 0) {
1529 l_ptr->retransm_queue_head = msg_seqno(msg);
1530 l_ptr->retransm_queue_size = retransmits;
1531 } else {
1532 err("Unexpected retransmit on link %s (qsize=%d)\n",
1533 l_ptr->name, l_ptr->retransm_queue_size);
1534 }
1535 return;
1536 } else {
1537 /* Detect repeated retransmit failures on uncongested bearer */
1538
1539 if (l_ptr->last_retransmitted == msg_seqno(msg)) {
1540 if (++l_ptr->stale_count > 100) {
1541 link_retransmit_failure(l_ptr, buf);
1542 return;
1543 }
1544 } else {
1545 l_ptr->last_retransmitted = msg_seqno(msg);
1546 l_ptr->stale_count = 1;
1547 }
1548 }
1549
1550 while (retransmits && (buf != l_ptr->next_out) && buf) {
1551 msg = buf_msg(buf);
1552 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
1553 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1554 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) {
1555 buf = buf->next;
1556 retransmits--;
1557 l_ptr->stats.retransmitted++;
1558 } else {
1559 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr);
1560 l_ptr->stats.bearer_congs++;
1561 l_ptr->retransm_queue_head = msg_seqno(buf_msg(buf));
1562 l_ptr->retransm_queue_size = retransmits;
1563 return;
1564 }
1565 }
1566
1567 l_ptr->retransm_queue_head = l_ptr->retransm_queue_size = 0;
1568 }
1569
1570 /**
1571 * link_insert_deferred_queue - insert deferred messages back into receive chain
1572 */
1573
1574 static struct sk_buff *link_insert_deferred_queue(struct link *l_ptr,
1575 struct sk_buff *buf)
1576 {
1577 u32 seq_no;
1578
1579 if (l_ptr->oldest_deferred_in == NULL)
1580 return buf;
1581
1582 seq_no = msg_seqno(buf_msg(l_ptr->oldest_deferred_in));
1583 if (seq_no == mod(l_ptr->next_in_no)) {
1584 l_ptr->newest_deferred_in->next = buf;
1585 buf = l_ptr->oldest_deferred_in;
1586 l_ptr->oldest_deferred_in = NULL;
1587 l_ptr->deferred_inqueue_sz = 0;
1588 }
1589 return buf;
1590 }
1591
1592 /**
1593 * link_recv_buf_validate - validate basic format of received message
1594 *
1595 * This routine ensures a TIPC message has an acceptable header, and at least
1596 * as much data as the header indicates it should. The routine also ensures
1597 * that the entire message header is stored in the main fragment of the message
1598 * buffer, to simplify future access to message header fields.
1599 *
1600 * Note: Having extra info present in the message header or data areas is OK.
1601 * TIPC will ignore the excess, under the assumption that it is optional info
1602 * introduced by a later release of the protocol.
1603 */
1604
1605 static int link_recv_buf_validate(struct sk_buff *buf)
1606 {
1607 static u32 min_data_hdr_size[8] = {
1608 SHORT_H_SIZE, MCAST_H_SIZE, NAMED_H_SIZE, BASIC_H_SIZE,
1609 MAX_H_SIZE, MAX_H_SIZE, MAX_H_SIZE, MAX_H_SIZE
1610 };
1611
1612 struct tipc_msg *msg;
1613 u32 tipc_hdr[2];
1614 u32 size;
1615 u32 hdr_size;
1616 u32 min_hdr_size;
1617
1618 if (unlikely(buf->len < MIN_H_SIZE))
1619 return 0;
1620
1621 msg = skb_header_pointer(buf, 0, sizeof(tipc_hdr), tipc_hdr);
1622 if (msg == NULL)
1623 return 0;
1624
1625 if (unlikely(msg_version(msg) != TIPC_VERSION))
1626 return 0;
1627
1628 size = msg_size(msg);
1629 hdr_size = msg_hdr_sz(msg);
1630 min_hdr_size = msg_isdata(msg) ?
1631 min_data_hdr_size[msg_type(msg)] : INT_H_SIZE;
1632
1633 if (unlikely((hdr_size < min_hdr_size) ||
1634 (size < hdr_size) ||
1635 (buf->len < size) ||
1636 (size - hdr_size > TIPC_MAX_USER_MSG_SIZE)))
1637 return 0;
1638
1639 return pskb_may_pull(buf, hdr_size);
1640 }
1641
1642 /**
1643 * tipc_recv_msg - process TIPC messages arriving from off-node
1644 * @head: pointer to message buffer chain
1645 * @tb_ptr: pointer to bearer message arrived on
1646 *
1647 * Invoked with no locks held. Bearer pointer must point to a valid bearer
1648 * structure (i.e. cannot be NULL), but bearer can be inactive.
1649 */
1650
1651 void tipc_recv_msg(struct sk_buff *head, struct tipc_bearer *b_ptr)
1652 {
1653 read_lock_bh(&tipc_net_lock);
1654 while (head) {
1655 struct tipc_node *n_ptr;
1656 struct link *l_ptr;
1657 struct sk_buff *crs;
1658 struct sk_buff *buf = head;
1659 struct tipc_msg *msg;
1660 u32 seq_no;
1661 u32 ackd;
1662 u32 released = 0;
1663 int type;
1664
1665 head = head->next;
1666
1667 /* Ensure bearer is still enabled */
1668
1669 if (unlikely(!b_ptr->active))
1670 goto cont;
1671
1672 /* Ensure message is well-formed */
1673
1674 if (unlikely(!link_recv_buf_validate(buf)))
1675 goto cont;
1676
1677 /* Ensure message data is a single contiguous unit */
1678
1679 if (unlikely(buf_linearize(buf)))
1680 goto cont;
1681
1682 /* Handle arrival of a non-unicast link message */
1683
1684 msg = buf_msg(buf);
1685
1686 if (unlikely(msg_non_seq(msg))) {
1687 if (msg_user(msg) == LINK_CONFIG)
1688 tipc_disc_recv_msg(buf, b_ptr);
1689 else
1690 tipc_bclink_recv_pkt(buf);
1691 continue;
1692 }
1693
1694 /* Discard unicast link messages destined for another node */
1695
1696 if (unlikely(!msg_short(msg) &&
1697 (msg_destnode(msg) != tipc_own_addr)))
1698 goto cont;
1699
1700 /* Locate neighboring node that sent message */
1701
1702 n_ptr = tipc_node_find(msg_prevnode(msg));
1703 if (unlikely(!n_ptr))
1704 goto cont;
1705 tipc_node_lock(n_ptr);
1706
1707 /* Locate unicast link endpoint that should handle message */
1708
1709 l_ptr = n_ptr->links[b_ptr->identity];
1710 if (unlikely(!l_ptr)) {
1711 tipc_node_unlock(n_ptr);
1712 goto cont;
1713 }
1714
1715 /* Verify that communication with node is currently allowed */
1716
1717 if ((n_ptr->block_setup & WAIT_PEER_DOWN) &&
1718 msg_user(msg) == LINK_PROTOCOL &&
1719 (msg_type(msg) == RESET_MSG ||
1720 msg_type(msg) == ACTIVATE_MSG) &&
1721 !msg_redundant_link(msg))
1722 n_ptr->block_setup &= ~WAIT_PEER_DOWN;
1723
1724 if (n_ptr->block_setup) {
1725 tipc_node_unlock(n_ptr);
1726 goto cont;
1727 }
1728
1729 /* Validate message sequence number info */
1730
1731 seq_no = msg_seqno(msg);
1732 ackd = msg_ack(msg);
1733
1734 /* Release acked messages */
1735
1736 if (less(n_ptr->bclink.acked, msg_bcast_ack(msg))) {
1737 if (tipc_node_is_up(n_ptr) && n_ptr->bclink.supported)
1738 tipc_bclink_acknowledge(n_ptr, msg_bcast_ack(msg));
1739 }
1740
1741 crs = l_ptr->first_out;
1742 while ((crs != l_ptr->next_out) &&
1743 less_eq(msg_seqno(buf_msg(crs)), ackd)) {
1744 struct sk_buff *next = crs->next;
1745
1746 buf_discard(crs);
1747 crs = next;
1748 released++;
1749 }
1750 if (released) {
1751 l_ptr->first_out = crs;
1752 l_ptr->out_queue_size -= released;
1753 }
1754
1755 /* Try sending any messages link endpoint has pending */
1756
1757 if (unlikely(l_ptr->next_out))
1758 tipc_link_push_queue(l_ptr);
1759 if (unlikely(!list_empty(&l_ptr->waiting_ports)))
1760 tipc_link_wakeup_ports(l_ptr, 0);
1761 if (unlikely(++l_ptr->unacked_window >= TIPC_MIN_LINK_WIN)) {
1762 l_ptr->stats.sent_acks++;
1763 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, 0, 0);
1764 }
1765
1766 /* Now (finally!) process the incoming message */
1767
1768 protocol_check:
1769 if (likely(link_working_working(l_ptr))) {
1770 if (likely(seq_no == mod(l_ptr->next_in_no))) {
1771 l_ptr->next_in_no++;
1772 if (unlikely(l_ptr->oldest_deferred_in))
1773 head = link_insert_deferred_queue(l_ptr,
1774 head);
1775 if (likely(msg_is_dest(msg, tipc_own_addr))) {
1776 deliver:
1777 if (likely(msg_isdata(msg))) {
1778 tipc_node_unlock(n_ptr);
1779 tipc_port_recv_msg(buf);
1780 continue;
1781 }
1782 switch (msg_user(msg)) {
1783 case MSG_BUNDLER:
1784 l_ptr->stats.recv_bundles++;
1785 l_ptr->stats.recv_bundled +=
1786 msg_msgcnt(msg);
1787 tipc_node_unlock(n_ptr);
1788 tipc_link_recv_bundle(buf);
1789 continue;
1790 case NAME_DISTRIBUTOR:
1791 tipc_node_unlock(n_ptr);
1792 tipc_named_recv(buf);
1793 continue;
1794 case CONN_MANAGER:
1795 tipc_node_unlock(n_ptr);
1796 tipc_port_recv_proto_msg(buf);
1797 continue;
1798 case MSG_FRAGMENTER:
1799 l_ptr->stats.recv_fragments++;
1800 if (tipc_link_recv_fragment(&l_ptr->defragm_buf,
1801 &buf, &msg)) {
1802 l_ptr->stats.recv_fragmented++;
1803 goto deliver;
1804 }
1805 break;
1806 case CHANGEOVER_PROTOCOL:
1807 type = msg_type(msg);
1808 if (link_recv_changeover_msg(&l_ptr, &buf)) {
1809 msg = buf_msg(buf);
1810 seq_no = msg_seqno(msg);
1811 if (type == ORIGINAL_MSG)
1812 goto deliver;
1813 goto protocol_check;
1814 }
1815 break;
1816 default:
1817 buf_discard(buf);
1818 buf = NULL;
1819 break;
1820 }
1821 }
1822 tipc_node_unlock(n_ptr);
1823 tipc_net_route_msg(buf);
1824 continue;
1825 }
1826 link_handle_out_of_seq_msg(l_ptr, buf);
1827 head = link_insert_deferred_queue(l_ptr, head);
1828 tipc_node_unlock(n_ptr);
1829 continue;
1830 }
1831
1832 if (msg_user(msg) == LINK_PROTOCOL) {
1833 link_recv_proto_msg(l_ptr, buf);
1834 head = link_insert_deferred_queue(l_ptr, head);
1835 tipc_node_unlock(n_ptr);
1836 continue;
1837 }
1838 link_state_event(l_ptr, TRAFFIC_MSG_EVT);
1839
1840 if (link_working_working(l_ptr)) {
1841 /* Re-insert in front of queue */
1842 buf->next = head;
1843 head = buf;
1844 tipc_node_unlock(n_ptr);
1845 continue;
1846 }
1847 tipc_node_unlock(n_ptr);
1848 cont:
1849 buf_discard(buf);
1850 }
1851 read_unlock_bh(&tipc_net_lock);
1852 }
1853
1854 /*
1855 * link_defer_buf(): Sort a received out-of-sequence packet
1856 * into the deferred reception queue.
1857 * Returns the increase of the queue length,i.e. 0 or 1
1858 */
1859
1860 u32 tipc_link_defer_pkt(struct sk_buff **head,
1861 struct sk_buff **tail,
1862 struct sk_buff *buf)
1863 {
1864 struct sk_buff *prev = NULL;
1865 struct sk_buff *crs = *head;
1866 u32 seq_no = msg_seqno(buf_msg(buf));
1867
1868 buf->next = NULL;
1869
1870 /* Empty queue ? */
1871 if (*head == NULL) {
1872 *head = *tail = buf;
1873 return 1;
1874 }
1875
1876 /* Last ? */
1877 if (less(msg_seqno(buf_msg(*tail)), seq_no)) {
1878 (*tail)->next = buf;
1879 *tail = buf;
1880 return 1;
1881 }
1882
1883 /* Scan through queue and sort it in */
1884 do {
1885 struct tipc_msg *msg = buf_msg(crs);
1886
1887 if (less(seq_no, msg_seqno(msg))) {
1888 buf->next = crs;
1889 if (prev)
1890 prev->next = buf;
1891 else
1892 *head = buf;
1893 return 1;
1894 }
1895 if (seq_no == msg_seqno(msg))
1896 break;
1897 prev = crs;
1898 crs = crs->next;
1899 } while (crs);
1900
1901 /* Message is a duplicate of an existing message */
1902
1903 buf_discard(buf);
1904 return 0;
1905 }
1906
1907 /**
1908 * link_handle_out_of_seq_msg - handle arrival of out-of-sequence packet
1909 */
1910
1911 static void link_handle_out_of_seq_msg(struct link *l_ptr,
1912 struct sk_buff *buf)
1913 {
1914 u32 seq_no = msg_seqno(buf_msg(buf));
1915
1916 if (likely(msg_user(buf_msg(buf)) == LINK_PROTOCOL)) {
1917 link_recv_proto_msg(l_ptr, buf);
1918 return;
1919 }
1920
1921 /* Record OOS packet arrival (force mismatch on next timeout) */
1922
1923 l_ptr->checkpoint--;
1924
1925 /*
1926 * Discard packet if a duplicate; otherwise add it to deferred queue
1927 * and notify peer of gap as per protocol specification
1928 */
1929
1930 if (less(seq_no, mod(l_ptr->next_in_no))) {
1931 l_ptr->stats.duplicates++;
1932 buf_discard(buf);
1933 return;
1934 }
1935
1936 if (tipc_link_defer_pkt(&l_ptr->oldest_deferred_in,
1937 &l_ptr->newest_deferred_in, buf)) {
1938 l_ptr->deferred_inqueue_sz++;
1939 l_ptr->stats.deferred_recv++;
1940 if ((l_ptr->deferred_inqueue_sz % 16) == 1)
1941 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, 0, 0);
1942 } else
1943 l_ptr->stats.duplicates++;
1944 }
1945
1946 /*
1947 * Send protocol message to the other endpoint.
1948 */
1949 void tipc_link_send_proto_msg(struct link *l_ptr, u32 msg_typ, int probe_msg,
1950 u32 gap, u32 tolerance, u32 priority, u32 ack_mtu)
1951 {
1952 struct sk_buff *buf = NULL;
1953 struct tipc_msg *msg = l_ptr->pmsg;
1954 u32 msg_size = sizeof(l_ptr->proto_msg);
1955 int r_flag;
1956
1957 if (link_blocked(l_ptr))
1958 return;
1959
1960 /* Abort non-RESET send if communication with node is prohibited */
1961
1962 if ((l_ptr->owner->block_setup) && (msg_typ != RESET_MSG))
1963 return;
1964
1965 msg_set_type(msg, msg_typ);
1966 msg_set_net_plane(msg, l_ptr->b_ptr->net_plane);
1967 msg_set_bcast_ack(msg, mod(l_ptr->owner->bclink.last_in));
1968 msg_set_last_bcast(msg, tipc_bclink_get_last_sent());
1969
1970 if (msg_typ == STATE_MSG) {
1971 u32 next_sent = mod(l_ptr->next_out_no);
1972
1973 if (!tipc_link_is_up(l_ptr))
1974 return;
1975 if (l_ptr->next_out)
1976 next_sent = msg_seqno(buf_msg(l_ptr->next_out));
1977 msg_set_next_sent(msg, next_sent);
1978 if (l_ptr->oldest_deferred_in) {
1979 u32 rec = msg_seqno(buf_msg(l_ptr->oldest_deferred_in));
1980 gap = mod(rec - mod(l_ptr->next_in_no));
1981 }
1982 msg_set_seq_gap(msg, gap);
1983 if (gap)
1984 l_ptr->stats.sent_nacks++;
1985 msg_set_link_tolerance(msg, tolerance);
1986 msg_set_linkprio(msg, priority);
1987 msg_set_max_pkt(msg, ack_mtu);
1988 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
1989 msg_set_probe(msg, probe_msg != 0);
1990 if (probe_msg) {
1991 u32 mtu = l_ptr->max_pkt;
1992
1993 if ((mtu < l_ptr->max_pkt_target) &&
1994 link_working_working(l_ptr) &&
1995 l_ptr->fsm_msg_cnt) {
1996 msg_size = (mtu + (l_ptr->max_pkt_target - mtu)/2 + 2) & ~3;
1997 if (l_ptr->max_pkt_probes == 10) {
1998 l_ptr->max_pkt_target = (msg_size - 4);
1999 l_ptr->max_pkt_probes = 0;
2000 msg_size = (mtu + (l_ptr->max_pkt_target - mtu)/2 + 2) & ~3;
2001 }
2002 l_ptr->max_pkt_probes++;
2003 }
2004
2005 l_ptr->stats.sent_probes++;
2006 }
2007 l_ptr->stats.sent_states++;
2008 } else { /* RESET_MSG or ACTIVATE_MSG */
2009 msg_set_ack(msg, mod(l_ptr->reset_checkpoint - 1));
2010 msg_set_seq_gap(msg, 0);
2011 msg_set_next_sent(msg, 1);
2012 msg_set_probe(msg, 0);
2013 msg_set_link_tolerance(msg, l_ptr->tolerance);
2014 msg_set_linkprio(msg, l_ptr->priority);
2015 msg_set_max_pkt(msg, l_ptr->max_pkt_target);
2016 }
2017
2018 r_flag = (l_ptr->owner->working_links > tipc_link_is_up(l_ptr));
2019 msg_set_redundant_link(msg, r_flag);
2020 msg_set_linkprio(msg, l_ptr->priority);
2021
2022 /* Ensure sequence number will not fit : */
2023
2024 msg_set_seqno(msg, mod(l_ptr->next_out_no + (0xffff/2)));
2025
2026 /* Congestion? */
2027
2028 if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr)) {
2029 if (!l_ptr->proto_msg_queue) {
2030 l_ptr->proto_msg_queue =
2031 tipc_buf_acquire(sizeof(l_ptr->proto_msg));
2032 }
2033 buf = l_ptr->proto_msg_queue;
2034 if (!buf)
2035 return;
2036 skb_copy_to_linear_data(buf, msg, sizeof(l_ptr->proto_msg));
2037 return;
2038 }
2039
2040 /* Message can be sent */
2041
2042 buf = tipc_buf_acquire(msg_size);
2043 if (!buf)
2044 return;
2045
2046 skb_copy_to_linear_data(buf, msg, sizeof(l_ptr->proto_msg));
2047 msg_set_size(buf_msg(buf), msg_size);
2048
2049 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) {
2050 l_ptr->unacked_window = 0;
2051 buf_discard(buf);
2052 return;
2053 }
2054
2055 /* New congestion */
2056 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr);
2057 l_ptr->proto_msg_queue = buf;
2058 l_ptr->stats.bearer_congs++;
2059 }
2060
2061 /*
2062 * Receive protocol message :
2063 * Note that network plane id propagates through the network, and may
2064 * change at any time. The node with lowest address rules
2065 */
2066
2067 static void link_recv_proto_msg(struct link *l_ptr, struct sk_buff *buf)
2068 {
2069 u32 rec_gap = 0;
2070 u32 max_pkt_info;
2071 u32 max_pkt_ack;
2072 u32 msg_tol;
2073 struct tipc_msg *msg = buf_msg(buf);
2074
2075 if (link_blocked(l_ptr))
2076 goto exit;
2077
2078 /* record unnumbered packet arrival (force mismatch on next timeout) */
2079
2080 l_ptr->checkpoint--;
2081
2082 if (l_ptr->b_ptr->net_plane != msg_net_plane(msg))
2083 if (tipc_own_addr > msg_prevnode(msg))
2084 l_ptr->b_ptr->net_plane = msg_net_plane(msg);
2085
2086 l_ptr->owner->permit_changeover = msg_redundant_link(msg);
2087
2088 switch (msg_type(msg)) {
2089
2090 case RESET_MSG:
2091 if (!link_working_unknown(l_ptr) &&
2092 (l_ptr->peer_session != INVALID_SESSION)) {
2093 if (less_eq(msg_session(msg), l_ptr->peer_session))
2094 break; /* duplicate or old reset: ignore */
2095 }
2096
2097 if (!msg_redundant_link(msg) && (link_working_working(l_ptr) ||
2098 link_working_unknown(l_ptr))) {
2099 /*
2100 * peer has lost contact -- don't allow peer's links
2101 * to reactivate before we recognize loss & clean up
2102 */
2103 l_ptr->owner->block_setup = WAIT_NODE_DOWN;
2104 }
2105
2106 /* fall thru' */
2107 case ACTIVATE_MSG:
2108 /* Update link settings according other endpoint's values */
2109
2110 strcpy((strrchr(l_ptr->name, ':') + 1), (char *)msg_data(msg));
2111
2112 msg_tol = msg_link_tolerance(msg);
2113 if (msg_tol > l_ptr->tolerance)
2114 link_set_supervision_props(l_ptr, msg_tol);
2115
2116 if (msg_linkprio(msg) > l_ptr->priority)
2117 l_ptr->priority = msg_linkprio(msg);
2118
2119 max_pkt_info = msg_max_pkt(msg);
2120 if (max_pkt_info) {
2121 if (max_pkt_info < l_ptr->max_pkt_target)
2122 l_ptr->max_pkt_target = max_pkt_info;
2123 if (l_ptr->max_pkt > l_ptr->max_pkt_target)
2124 l_ptr->max_pkt = l_ptr->max_pkt_target;
2125 } else {
2126 l_ptr->max_pkt = l_ptr->max_pkt_target;
2127 }
2128 l_ptr->owner->bclink.supported = (max_pkt_info != 0);
2129
2130 link_state_event(l_ptr, msg_type(msg));
2131
2132 l_ptr->peer_session = msg_session(msg);
2133 l_ptr->peer_bearer_id = msg_bearer_id(msg);
2134
2135 /* Synchronize broadcast sequence numbers */
2136 if (!tipc_node_redundant_links(l_ptr->owner))
2137 l_ptr->owner->bclink.last_in = mod(msg_last_bcast(msg));
2138 break;
2139 case STATE_MSG:
2140
2141 msg_tol = msg_link_tolerance(msg);
2142 if (msg_tol)
2143 link_set_supervision_props(l_ptr, msg_tol);
2144
2145 if (msg_linkprio(msg) &&
2146 (msg_linkprio(msg) != l_ptr->priority)) {
2147 warn("Resetting link <%s>, priority change %u->%u\n",
2148 l_ptr->name, l_ptr->priority, msg_linkprio(msg));
2149 l_ptr->priority = msg_linkprio(msg);
2150 tipc_link_reset(l_ptr); /* Enforce change to take effect */
2151 break;
2152 }
2153 link_state_event(l_ptr, TRAFFIC_MSG_EVT);
2154 l_ptr->stats.recv_states++;
2155 if (link_reset_unknown(l_ptr))
2156 break;
2157
2158 if (less_eq(mod(l_ptr->next_in_no), msg_next_sent(msg))) {
2159 rec_gap = mod(msg_next_sent(msg) -
2160 mod(l_ptr->next_in_no));
2161 }
2162
2163 max_pkt_ack = msg_max_pkt(msg);
2164 if (max_pkt_ack > l_ptr->max_pkt) {
2165 l_ptr->max_pkt = max_pkt_ack;
2166 l_ptr->max_pkt_probes = 0;
2167 }
2168
2169 max_pkt_ack = 0;
2170 if (msg_probe(msg)) {
2171 l_ptr->stats.recv_probes++;
2172 if (msg_size(msg) > sizeof(l_ptr->proto_msg))
2173 max_pkt_ack = msg_size(msg);
2174 }
2175
2176 /* Protocol message before retransmits, reduce loss risk */
2177
2178 tipc_bclink_check_gap(l_ptr->owner, msg_last_bcast(msg));
2179
2180 if (rec_gap || (msg_probe(msg))) {
2181 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
2182 0, rec_gap, 0, 0, max_pkt_ack);
2183 }
2184 if (msg_seq_gap(msg)) {
2185 l_ptr->stats.recv_nacks++;
2186 tipc_link_retransmit(l_ptr, l_ptr->first_out,
2187 msg_seq_gap(msg));
2188 }
2189 break;
2190 }
2191 exit:
2192 buf_discard(buf);
2193 }
2194
2195
2196 /*
2197 * tipc_link_tunnel(): Send one message via a link belonging to
2198 * another bearer. Owner node is locked.
2199 */
2200 static void tipc_link_tunnel(struct link *l_ptr,
2201 struct tipc_msg *tunnel_hdr,
2202 struct tipc_msg *msg,
2203 u32 selector)
2204 {
2205 struct link *tunnel;
2206 struct sk_buff *buf;
2207 u32 length = msg_size(msg);
2208
2209 tunnel = l_ptr->owner->active_links[selector & 1];
2210 if (!tipc_link_is_up(tunnel)) {
2211 warn("Link changeover error, "
2212 "tunnel link no longer available\n");
2213 return;
2214 }
2215 msg_set_size(tunnel_hdr, length + INT_H_SIZE);
2216 buf = tipc_buf_acquire(length + INT_H_SIZE);
2217 if (!buf) {
2218 warn("Link changeover error, "
2219 "unable to send tunnel msg\n");
2220 return;
2221 }
2222 skb_copy_to_linear_data(buf, tunnel_hdr, INT_H_SIZE);
2223 skb_copy_to_linear_data_offset(buf, INT_H_SIZE, msg, length);
2224 tipc_link_send_buf(tunnel, buf);
2225 }
2226
2227
2228
2229 /*
2230 * changeover(): Send whole message queue via the remaining link
2231 * Owner node is locked.
2232 */
2233
2234 void tipc_link_changeover(struct link *l_ptr)
2235 {
2236 u32 msgcount = l_ptr->out_queue_size;
2237 struct sk_buff *crs = l_ptr->first_out;
2238 struct link *tunnel = l_ptr->owner->active_links[0];
2239 struct tipc_msg tunnel_hdr;
2240 int split_bundles;
2241
2242 if (!tunnel)
2243 return;
2244
2245 if (!l_ptr->owner->permit_changeover) {
2246 warn("Link changeover error, "
2247 "peer did not permit changeover\n");
2248 return;
2249 }
2250
2251 tipc_msg_init(&tunnel_hdr, CHANGEOVER_PROTOCOL,
2252 ORIGINAL_MSG, INT_H_SIZE, l_ptr->addr);
2253 msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id);
2254 msg_set_msgcnt(&tunnel_hdr, msgcount);
2255
2256 if (!l_ptr->first_out) {
2257 struct sk_buff *buf;
2258
2259 buf = tipc_buf_acquire(INT_H_SIZE);
2260 if (buf) {
2261 skb_copy_to_linear_data(buf, &tunnel_hdr, INT_H_SIZE);
2262 msg_set_size(&tunnel_hdr, INT_H_SIZE);
2263 tipc_link_send_buf(tunnel, buf);
2264 } else {
2265 warn("Link changeover error, "
2266 "unable to send changeover msg\n");
2267 }
2268 return;
2269 }
2270
2271 split_bundles = (l_ptr->owner->active_links[0] !=
2272 l_ptr->owner->active_links[1]);
2273
2274 while (crs) {
2275 struct tipc_msg *msg = buf_msg(crs);
2276
2277 if ((msg_user(msg) == MSG_BUNDLER) && split_bundles) {
2278 struct tipc_msg *m = msg_get_wrapped(msg);
2279 unchar *pos = (unchar *)m;
2280
2281 msgcount = msg_msgcnt(msg);
2282 while (msgcount--) {
2283 msg_set_seqno(m, msg_seqno(msg));
2284 tipc_link_tunnel(l_ptr, &tunnel_hdr, m,
2285 msg_link_selector(m));
2286 pos += align(msg_size(m));
2287 m = (struct tipc_msg *)pos;
2288 }
2289 } else {
2290 tipc_link_tunnel(l_ptr, &tunnel_hdr, msg,
2291 msg_link_selector(msg));
2292 }
2293 crs = crs->next;
2294 }
2295 }
2296
2297 void tipc_link_send_duplicate(struct link *l_ptr, struct link *tunnel)
2298 {
2299 struct sk_buff *iter;
2300 struct tipc_msg tunnel_hdr;
2301
2302 tipc_msg_init(&tunnel_hdr, CHANGEOVER_PROTOCOL,
2303 DUPLICATE_MSG, INT_H_SIZE, l_ptr->addr);
2304 msg_set_msgcnt(&tunnel_hdr, l_ptr->out_queue_size);
2305 msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id);
2306 iter = l_ptr->first_out;
2307 while (iter) {
2308 struct sk_buff *outbuf;
2309 struct tipc_msg *msg = buf_msg(iter);
2310 u32 length = msg_size(msg);
2311
2312 if (msg_user(msg) == MSG_BUNDLER)
2313 msg_set_type(msg, CLOSED_MSG);
2314 msg_set_ack(msg, mod(l_ptr->next_in_no - 1)); /* Update */
2315 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
2316 msg_set_size(&tunnel_hdr, length + INT_H_SIZE);
2317 outbuf = tipc_buf_acquire(length + INT_H_SIZE);
2318 if (outbuf == NULL) {
2319 warn("Link changeover error, "
2320 "unable to send duplicate msg\n");
2321 return;
2322 }
2323 skb_copy_to_linear_data(outbuf, &tunnel_hdr, INT_H_SIZE);
2324 skb_copy_to_linear_data_offset(outbuf, INT_H_SIZE, iter->data,
2325 length);
2326 tipc_link_send_buf(tunnel, outbuf);
2327 if (!tipc_link_is_up(l_ptr))
2328 return;
2329 iter = iter->next;
2330 }
2331 }
2332
2333
2334
2335 /**
2336 * buf_extract - extracts embedded TIPC message from another message
2337 * @skb: encapsulating message buffer
2338 * @from_pos: offset to extract from
2339 *
2340 * Returns a new message buffer containing an embedded message. The
2341 * encapsulating message itself is left unchanged.
2342 */
2343
2344 static struct sk_buff *buf_extract(struct sk_buff *skb, u32 from_pos)
2345 {
2346 struct tipc_msg *msg = (struct tipc_msg *)(skb->data + from_pos);
2347 u32 size = msg_size(msg);
2348 struct sk_buff *eb;
2349
2350 eb = tipc_buf_acquire(size);
2351 if (eb)
2352 skb_copy_to_linear_data(eb, msg, size);
2353 return eb;
2354 }
2355
2356 /*
2357 * link_recv_changeover_msg(): Receive tunneled packet sent
2358 * via other link. Node is locked. Return extracted buffer.
2359 */
2360
2361 static int link_recv_changeover_msg(struct link **l_ptr,
2362 struct sk_buff **buf)
2363 {
2364 struct sk_buff *tunnel_buf = *buf;
2365 struct link *dest_link;
2366 struct tipc_msg *msg;
2367 struct tipc_msg *tunnel_msg = buf_msg(tunnel_buf);
2368 u32 msg_typ = msg_type(tunnel_msg);
2369 u32 msg_count = msg_msgcnt(tunnel_msg);
2370
2371 dest_link = (*l_ptr)->owner->links[msg_bearer_id(tunnel_msg)];
2372 if (!dest_link)
2373 goto exit;
2374 if (dest_link == *l_ptr) {
2375 err("Unexpected changeover message on link <%s>\n",
2376 (*l_ptr)->name);
2377 goto exit;
2378 }
2379 *l_ptr = dest_link;
2380 msg = msg_get_wrapped(tunnel_msg);
2381
2382 if (msg_typ == DUPLICATE_MSG) {
2383 if (less(msg_seqno(msg), mod(dest_link->next_in_no)))
2384 goto exit;
2385 *buf = buf_extract(tunnel_buf, INT_H_SIZE);
2386 if (*buf == NULL) {
2387 warn("Link changeover error, duplicate msg dropped\n");
2388 goto exit;
2389 }
2390 buf_discard(tunnel_buf);
2391 return 1;
2392 }
2393
2394 /* First original message ?: */
2395
2396 if (tipc_link_is_up(dest_link)) {
2397 info("Resetting link <%s>, changeover initiated by peer\n",
2398 dest_link->name);
2399 tipc_link_reset(dest_link);
2400 dest_link->exp_msg_count = msg_count;
2401 if (!msg_count)
2402 goto exit;
2403 } else if (dest_link->exp_msg_count == START_CHANGEOVER) {
2404 dest_link->exp_msg_count = msg_count;
2405 if (!msg_count)
2406 goto exit;
2407 }
2408
2409 /* Receive original message */
2410
2411 if (dest_link->exp_msg_count == 0) {
2412 warn("Link switchover error, "
2413 "got too many tunnelled messages\n");
2414 goto exit;
2415 }
2416 dest_link->exp_msg_count--;
2417 if (less(msg_seqno(msg), dest_link->reset_checkpoint)) {
2418 goto exit;
2419 } else {
2420 *buf = buf_extract(tunnel_buf, INT_H_SIZE);
2421 if (*buf != NULL) {
2422 buf_discard(tunnel_buf);
2423 return 1;
2424 } else {
2425 warn("Link changeover error, original msg dropped\n");
2426 }
2427 }
2428 exit:
2429 *buf = NULL;
2430 buf_discard(tunnel_buf);
2431 return 0;
2432 }
2433
2434 /*
2435 * Bundler functionality:
2436 */
2437 void tipc_link_recv_bundle(struct sk_buff *buf)
2438 {
2439 u32 msgcount = msg_msgcnt(buf_msg(buf));
2440 u32 pos = INT_H_SIZE;
2441 struct sk_buff *obuf;
2442
2443 while (msgcount--) {
2444 obuf = buf_extract(buf, pos);
2445 if (obuf == NULL) {
2446 warn("Link unable to unbundle message(s)\n");
2447 break;
2448 }
2449 pos += align(msg_size(buf_msg(obuf)));
2450 tipc_net_route_msg(obuf);
2451 }
2452 buf_discard(buf);
2453 }
2454
2455 /*
2456 * Fragmentation/defragmentation:
2457 */
2458
2459
2460 /*
2461 * link_send_long_buf: Entry for buffers needing fragmentation.
2462 * The buffer is complete, inclusive total message length.
2463 * Returns user data length.
2464 */
2465 static int link_send_long_buf(struct link *l_ptr, struct sk_buff *buf)
2466 {
2467 struct sk_buff *buf_chain = NULL;
2468 struct sk_buff *buf_chain_tail = (struct sk_buff *)&buf_chain;
2469 struct tipc_msg *inmsg = buf_msg(buf);
2470 struct tipc_msg fragm_hdr;
2471 u32 insize = msg_size(inmsg);
2472 u32 dsz = msg_data_sz(inmsg);
2473 unchar *crs = buf->data;
2474 u32 rest = insize;
2475 u32 pack_sz = l_ptr->max_pkt;
2476 u32 fragm_sz = pack_sz - INT_H_SIZE;
2477 u32 fragm_no = 0;
2478 u32 destaddr;
2479
2480 if (msg_short(inmsg))
2481 destaddr = l_ptr->addr;
2482 else
2483 destaddr = msg_destnode(inmsg);
2484
2485 /* Prepare reusable fragment header: */
2486
2487 tipc_msg_init(&fragm_hdr, MSG_FRAGMENTER, FIRST_FRAGMENT,
2488 INT_H_SIZE, destaddr);
2489
2490 /* Chop up message: */
2491
2492 while (rest > 0) {
2493 struct sk_buff *fragm;
2494
2495 if (rest <= fragm_sz) {
2496 fragm_sz = rest;
2497 msg_set_type(&fragm_hdr, LAST_FRAGMENT);
2498 }
2499 fragm = tipc_buf_acquire(fragm_sz + INT_H_SIZE);
2500 if (fragm == NULL) {
2501 buf_discard(buf);
2502 while (buf_chain) {
2503 buf = buf_chain;
2504 buf_chain = buf_chain->next;
2505 buf_discard(buf);
2506 }
2507 return -ENOMEM;
2508 }
2509 msg_set_size(&fragm_hdr, fragm_sz + INT_H_SIZE);
2510 fragm_no++;
2511 msg_set_fragm_no(&fragm_hdr, fragm_no);
2512 skb_copy_to_linear_data(fragm, &fragm_hdr, INT_H_SIZE);
2513 skb_copy_to_linear_data_offset(fragm, INT_H_SIZE, crs,
2514 fragm_sz);
2515 buf_chain_tail->next = fragm;
2516 buf_chain_tail = fragm;
2517
2518 rest -= fragm_sz;
2519 crs += fragm_sz;
2520 msg_set_type(&fragm_hdr, FRAGMENT);
2521 }
2522 buf_discard(buf);
2523
2524 /* Append chain of fragments to send queue & send them */
2525
2526 l_ptr->long_msg_seq_no++;
2527 link_add_chain_to_outqueue(l_ptr, buf_chain, l_ptr->long_msg_seq_no);
2528 l_ptr->stats.sent_fragments += fragm_no;
2529 l_ptr->stats.sent_fragmented++;
2530 tipc_link_push_queue(l_ptr);
2531
2532 return dsz;
2533 }
2534
2535 /*
2536 * A pending message being re-assembled must store certain values
2537 * to handle subsequent fragments correctly. The following functions
2538 * help storing these values in unused, available fields in the
2539 * pending message. This makes dynamic memory allocation unnecessary.
2540 */
2541
2542 static void set_long_msg_seqno(struct sk_buff *buf, u32 seqno)
2543 {
2544 msg_set_seqno(buf_msg(buf), seqno);
2545 }
2546
2547 static u32 get_fragm_size(struct sk_buff *buf)
2548 {
2549 return msg_ack(buf_msg(buf));
2550 }
2551
2552 static void set_fragm_size(struct sk_buff *buf, u32 sz)
2553 {
2554 msg_set_ack(buf_msg(buf), sz);
2555 }
2556
2557 static u32 get_expected_frags(struct sk_buff *buf)
2558 {
2559 return msg_bcast_ack(buf_msg(buf));
2560 }
2561
2562 static void set_expected_frags(struct sk_buff *buf, u32 exp)
2563 {
2564 msg_set_bcast_ack(buf_msg(buf), exp);
2565 }
2566
2567 static u32 get_timer_cnt(struct sk_buff *buf)
2568 {
2569 return msg_reroute_cnt(buf_msg(buf));
2570 }
2571
2572 static void incr_timer_cnt(struct sk_buff *buf)
2573 {
2574 msg_incr_reroute_cnt(buf_msg(buf));
2575 }
2576
2577 /*
2578 * tipc_link_recv_fragment(): Called with node lock on. Returns
2579 * the reassembled buffer if message is complete.
2580 */
2581 int tipc_link_recv_fragment(struct sk_buff **pending, struct sk_buff **fb,
2582 struct tipc_msg **m)
2583 {
2584 struct sk_buff *prev = NULL;
2585 struct sk_buff *fbuf = *fb;
2586 struct tipc_msg *fragm = buf_msg(fbuf);
2587 struct sk_buff *pbuf = *pending;
2588 u32 long_msg_seq_no = msg_long_msgno(fragm);
2589
2590 *fb = NULL;
2591
2592 /* Is there an incomplete message waiting for this fragment? */
2593
2594 while (pbuf && ((msg_seqno(buf_msg(pbuf)) != long_msg_seq_no) ||
2595 (msg_orignode(fragm) != msg_orignode(buf_msg(pbuf))))) {
2596 prev = pbuf;
2597 pbuf = pbuf->next;
2598 }
2599
2600 if (!pbuf && (msg_type(fragm) == FIRST_FRAGMENT)) {
2601 struct tipc_msg *imsg = (struct tipc_msg *)msg_data(fragm);
2602 u32 msg_sz = msg_size(imsg);
2603 u32 fragm_sz = msg_data_sz(fragm);
2604 u32 exp_fragm_cnt = msg_sz/fragm_sz + !!(msg_sz % fragm_sz);
2605 u32 max = TIPC_MAX_USER_MSG_SIZE + NAMED_H_SIZE;
2606 if (msg_type(imsg) == TIPC_MCAST_MSG)
2607 max = TIPC_MAX_USER_MSG_SIZE + MCAST_H_SIZE;
2608 if (msg_size(imsg) > max) {
2609 buf_discard(fbuf);
2610 return 0;
2611 }
2612 pbuf = tipc_buf_acquire(msg_size(imsg));
2613 if (pbuf != NULL) {
2614 pbuf->next = *pending;
2615 *pending = pbuf;
2616 skb_copy_to_linear_data(pbuf, imsg,
2617 msg_data_sz(fragm));
2618 /* Prepare buffer for subsequent fragments. */
2619
2620 set_long_msg_seqno(pbuf, long_msg_seq_no);
2621 set_fragm_size(pbuf, fragm_sz);
2622 set_expected_frags(pbuf, exp_fragm_cnt - 1);
2623 } else {
2624 warn("Link unable to reassemble fragmented message\n");
2625 }
2626 buf_discard(fbuf);
2627 return 0;
2628 } else if (pbuf && (msg_type(fragm) != FIRST_FRAGMENT)) {
2629 u32 dsz = msg_data_sz(fragm);
2630 u32 fsz = get_fragm_size(pbuf);
2631 u32 crs = ((msg_fragm_no(fragm) - 1) * fsz);
2632 u32 exp_frags = get_expected_frags(pbuf) - 1;
2633 skb_copy_to_linear_data_offset(pbuf, crs,
2634 msg_data(fragm), dsz);
2635 buf_discard(fbuf);
2636
2637 /* Is message complete? */
2638
2639 if (exp_frags == 0) {
2640 if (prev)
2641 prev->next = pbuf->next;
2642 else
2643 *pending = pbuf->next;
2644 msg_reset_reroute_cnt(buf_msg(pbuf));
2645 *fb = pbuf;
2646 *m = buf_msg(pbuf);
2647 return 1;
2648 }
2649 set_expected_frags(pbuf, exp_frags);
2650 return 0;
2651 }
2652 buf_discard(fbuf);
2653 return 0;
2654 }
2655
2656 /**
2657 * link_check_defragm_bufs - flush stale incoming message fragments
2658 * @l_ptr: pointer to link
2659 */
2660
2661 static void link_check_defragm_bufs(struct link *l_ptr)
2662 {
2663 struct sk_buff *prev = NULL;
2664 struct sk_buff *next = NULL;
2665 struct sk_buff *buf = l_ptr->defragm_buf;
2666
2667 if (!buf)
2668 return;
2669 if (!link_working_working(l_ptr))
2670 return;
2671 while (buf) {
2672 u32 cnt = get_timer_cnt(buf);
2673
2674 next = buf->next;
2675 if (cnt < 4) {
2676 incr_timer_cnt(buf);
2677 prev = buf;
2678 } else {
2679 if (prev)
2680 prev->next = buf->next;
2681 else
2682 l_ptr->defragm_buf = buf->next;
2683 buf_discard(buf);
2684 }
2685 buf = next;
2686 }
2687 }
2688
2689
2690
2691 static void link_set_supervision_props(struct link *l_ptr, u32 tolerance)
2692 {
2693 if ((tolerance < TIPC_MIN_LINK_TOL) || (tolerance > TIPC_MAX_LINK_TOL))
2694 return;
2695
2696 l_ptr->tolerance = tolerance;
2697 l_ptr->continuity_interval =
2698 ((tolerance / 4) > 500) ? 500 : tolerance / 4;
2699 l_ptr->abort_limit = tolerance / (l_ptr->continuity_interval / 4);
2700 }
2701
2702
2703 void tipc_link_set_queue_limits(struct link *l_ptr, u32 window)
2704 {
2705 /* Data messages from this node, inclusive FIRST_FRAGM */
2706 l_ptr->queue_limit[TIPC_LOW_IMPORTANCE] = window;
2707 l_ptr->queue_limit[TIPC_MEDIUM_IMPORTANCE] = (window / 3) * 4;
2708 l_ptr->queue_limit[TIPC_HIGH_IMPORTANCE] = (window / 3) * 5;
2709 l_ptr->queue_limit[TIPC_CRITICAL_IMPORTANCE] = (window / 3) * 6;
2710 /* Transiting data messages,inclusive FIRST_FRAGM */
2711 l_ptr->queue_limit[TIPC_LOW_IMPORTANCE + 4] = 300;
2712 l_ptr->queue_limit[TIPC_MEDIUM_IMPORTANCE + 4] = 600;
2713 l_ptr->queue_limit[TIPC_HIGH_IMPORTANCE + 4] = 900;
2714 l_ptr->queue_limit[TIPC_CRITICAL_IMPORTANCE + 4] = 1200;
2715 l_ptr->queue_limit[CONN_MANAGER] = 1200;
2716 l_ptr->queue_limit[CHANGEOVER_PROTOCOL] = 2500;
2717 l_ptr->queue_limit[NAME_DISTRIBUTOR] = 3000;
2718 /* FRAGMENT and LAST_FRAGMENT packets */
2719 l_ptr->queue_limit[MSG_FRAGMENTER] = 4000;
2720 }
2721
2722 /**
2723 * link_find_link - locate link by name
2724 * @name - ptr to link name string
2725 * @node - ptr to area to be filled with ptr to associated node
2726 *
2727 * Caller must hold 'tipc_net_lock' to ensure node and bearer are not deleted;
2728 * this also prevents link deletion.
2729 *
2730 * Returns pointer to link (or 0 if invalid link name).
2731 */
2732
2733 static struct link *link_find_link(const char *name, struct tipc_node **node)
2734 {
2735 struct link_name link_name_parts;
2736 struct tipc_bearer *b_ptr;
2737 struct link *l_ptr;
2738
2739 if (!link_name_validate(name, &link_name_parts))
2740 return NULL;
2741
2742 b_ptr = tipc_bearer_find_interface(link_name_parts.if_local);
2743 if (!b_ptr)
2744 return NULL;
2745
2746 *node = tipc_node_find(link_name_parts.addr_peer);
2747 if (!*node)
2748 return NULL;
2749
2750 l_ptr = (*node)->links[b_ptr->identity];
2751 if (!l_ptr || strcmp(l_ptr->name, name))
2752 return NULL;
2753
2754 return l_ptr;
2755 }
2756
2757 struct sk_buff *tipc_link_cmd_config(const void *req_tlv_area, int req_tlv_space,
2758 u16 cmd)
2759 {
2760 struct tipc_link_config *args;
2761 u32 new_value;
2762 struct link *l_ptr;
2763 struct tipc_node *node;
2764 int res;
2765
2766 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_CONFIG))
2767 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
2768
2769 args = (struct tipc_link_config *)TLV_DATA(req_tlv_area);
2770 new_value = ntohl(args->value);
2771
2772 if (!strcmp(args->name, tipc_bclink_name)) {
2773 if ((cmd == TIPC_CMD_SET_LINK_WINDOW) &&
2774 (tipc_bclink_set_queue_limits(new_value) == 0))
2775 return tipc_cfg_reply_none();
2776 return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED
2777 " (cannot change setting on broadcast link)");
2778 }
2779
2780 read_lock_bh(&tipc_net_lock);
2781 l_ptr = link_find_link(args->name, &node);
2782 if (!l_ptr) {
2783 read_unlock_bh(&tipc_net_lock);
2784 return tipc_cfg_reply_error_string("link not found");
2785 }
2786
2787 tipc_node_lock(node);
2788 res = -EINVAL;
2789 switch (cmd) {
2790 case TIPC_CMD_SET_LINK_TOL:
2791 if ((new_value >= TIPC_MIN_LINK_TOL) &&
2792 (new_value <= TIPC_MAX_LINK_TOL)) {
2793 link_set_supervision_props(l_ptr, new_value);
2794 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
2795 0, 0, new_value, 0, 0);
2796 res = 0;
2797 }
2798 break;
2799 case TIPC_CMD_SET_LINK_PRI:
2800 if ((new_value >= TIPC_MIN_LINK_PRI) &&
2801 (new_value <= TIPC_MAX_LINK_PRI)) {
2802 l_ptr->priority = new_value;
2803 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
2804 0, 0, 0, new_value, 0);
2805 res = 0;
2806 }
2807 break;
2808 case TIPC_CMD_SET_LINK_WINDOW:
2809 if ((new_value >= TIPC_MIN_LINK_WIN) &&
2810 (new_value <= TIPC_MAX_LINK_WIN)) {
2811 tipc_link_set_queue_limits(l_ptr, new_value);
2812 res = 0;
2813 }
2814 break;
2815 }
2816 tipc_node_unlock(node);
2817
2818 read_unlock_bh(&tipc_net_lock);
2819 if (res)
2820 return tipc_cfg_reply_error_string("cannot change link setting");
2821
2822 return tipc_cfg_reply_none();
2823 }
2824
2825 /**
2826 * link_reset_statistics - reset link statistics
2827 * @l_ptr: pointer to link
2828 */
2829
2830 static void link_reset_statistics(struct link *l_ptr)
2831 {
2832 memset(&l_ptr->stats, 0, sizeof(l_ptr->stats));
2833 l_ptr->stats.sent_info = l_ptr->next_out_no;
2834 l_ptr->stats.recv_info = l_ptr->next_in_no;
2835 }
2836
2837 struct sk_buff *tipc_link_cmd_reset_stats(const void *req_tlv_area, int req_tlv_space)
2838 {
2839 char *link_name;
2840 struct link *l_ptr;
2841 struct tipc_node *node;
2842
2843 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_NAME))
2844 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
2845
2846 link_name = (char *)TLV_DATA(req_tlv_area);
2847 if (!strcmp(link_name, tipc_bclink_name)) {
2848 if (tipc_bclink_reset_stats())
2849 return tipc_cfg_reply_error_string("link not found");
2850 return tipc_cfg_reply_none();
2851 }
2852
2853 read_lock_bh(&tipc_net_lock);
2854 l_ptr = link_find_link(link_name, &node);
2855 if (!l_ptr) {
2856 read_unlock_bh(&tipc_net_lock);
2857 return tipc_cfg_reply_error_string("link not found");
2858 }
2859
2860 tipc_node_lock(node);
2861 link_reset_statistics(l_ptr);
2862 tipc_node_unlock(node);
2863 read_unlock_bh(&tipc_net_lock);
2864 return tipc_cfg_reply_none();
2865 }
2866
2867 /**
2868 * percent - convert count to a percentage of total (rounding up or down)
2869 */
2870
2871 static u32 percent(u32 count, u32 total)
2872 {
2873 return (count * 100 + (total / 2)) / total;
2874 }
2875
2876 /**
2877 * tipc_link_stats - print link statistics
2878 * @name: link name
2879 * @buf: print buffer area
2880 * @buf_size: size of print buffer area
2881 *
2882 * Returns length of print buffer data string (or 0 if error)
2883 */
2884
2885 static int tipc_link_stats(const char *name, char *buf, const u32 buf_size)
2886 {
2887 struct print_buf pb;
2888 struct link *l_ptr;
2889 struct tipc_node *node;
2890 char *status;
2891 u32 profile_total = 0;
2892
2893 if (!strcmp(name, tipc_bclink_name))
2894 return tipc_bclink_stats(buf, buf_size);
2895
2896 tipc_printbuf_init(&pb, buf, buf_size);
2897
2898 read_lock_bh(&tipc_net_lock);
2899 l_ptr = link_find_link(name, &node);
2900 if (!l_ptr) {
2901 read_unlock_bh(&tipc_net_lock);
2902 return 0;
2903 }
2904 tipc_node_lock(node);
2905
2906 if (tipc_link_is_active(l_ptr))
2907 status = "ACTIVE";
2908 else if (tipc_link_is_up(l_ptr))
2909 status = "STANDBY";
2910 else
2911 status = "DEFUNCT";
2912 tipc_printf(&pb, "Link <%s>\n"
2913 " %s MTU:%u Priority:%u Tolerance:%u ms"
2914 " Window:%u packets\n",
2915 l_ptr->name, status, l_ptr->max_pkt,
2916 l_ptr->priority, l_ptr->tolerance, l_ptr->queue_limit[0]);
2917 tipc_printf(&pb, " RX packets:%u fragments:%u/%u bundles:%u/%u\n",
2918 l_ptr->next_in_no - l_ptr->stats.recv_info,
2919 l_ptr->stats.recv_fragments,
2920 l_ptr->stats.recv_fragmented,
2921 l_ptr->stats.recv_bundles,
2922 l_ptr->stats.recv_bundled);
2923 tipc_printf(&pb, " TX packets:%u fragments:%u/%u bundles:%u/%u\n",
2924 l_ptr->next_out_no - l_ptr->stats.sent_info,
2925 l_ptr->stats.sent_fragments,
2926 l_ptr->stats.sent_fragmented,
2927 l_ptr->stats.sent_bundles,
2928 l_ptr->stats.sent_bundled);
2929 profile_total = l_ptr->stats.msg_length_counts;
2930 if (!profile_total)
2931 profile_total = 1;
2932 tipc_printf(&pb, " TX profile sample:%u packets average:%u octets\n"
2933 " 0-64:%u%% -256:%u%% -1024:%u%% -4096:%u%% "
2934 "-16384:%u%% -32768:%u%% -66000:%u%%\n",
2935 l_ptr->stats.msg_length_counts,
2936 l_ptr->stats.msg_lengths_total / profile_total,
2937 percent(l_ptr->stats.msg_length_profile[0], profile_total),
2938 percent(l_ptr->stats.msg_length_profile[1], profile_total),
2939 percent(l_ptr->stats.msg_length_profile[2], profile_total),
2940 percent(l_ptr->stats.msg_length_profile[3], profile_total),
2941 percent(l_ptr->stats.msg_length_profile[4], profile_total),
2942 percent(l_ptr->stats.msg_length_profile[5], profile_total),
2943 percent(l_ptr->stats.msg_length_profile[6], profile_total));
2944 tipc_printf(&pb, " RX states:%u probes:%u naks:%u defs:%u dups:%u\n",
2945 l_ptr->stats.recv_states,
2946 l_ptr->stats.recv_probes,
2947 l_ptr->stats.recv_nacks,
2948 l_ptr->stats.deferred_recv,
2949 l_ptr->stats.duplicates);
2950 tipc_printf(&pb, " TX states:%u probes:%u naks:%u acks:%u dups:%u\n",
2951 l_ptr->stats.sent_states,
2952 l_ptr->stats.sent_probes,
2953 l_ptr->stats.sent_nacks,
2954 l_ptr->stats.sent_acks,
2955 l_ptr->stats.retransmitted);
2956 tipc_printf(&pb, " Congestion bearer:%u link:%u Send queue max:%u avg:%u\n",
2957 l_ptr->stats.bearer_congs,
2958 l_ptr->stats.link_congs,
2959 l_ptr->stats.max_queue_sz,
2960 l_ptr->stats.queue_sz_counts
2961 ? (l_ptr->stats.accu_queue_sz / l_ptr->stats.queue_sz_counts)
2962 : 0);
2963
2964 tipc_node_unlock(node);
2965 read_unlock_bh(&tipc_net_lock);
2966 return tipc_printbuf_validate(&pb);
2967 }
2968
2969 #define MAX_LINK_STATS_INFO 2000
2970
2971 struct sk_buff *tipc_link_cmd_show_stats(const void *req_tlv_area, int req_tlv_space)
2972 {
2973 struct sk_buff *buf;
2974 struct tlv_desc *rep_tlv;
2975 int str_len;
2976
2977 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_NAME))
2978 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
2979
2980 buf = tipc_cfg_reply_alloc(TLV_SPACE(MAX_LINK_STATS_INFO));
2981 if (!buf)
2982 return NULL;
2983
2984 rep_tlv = (struct tlv_desc *)buf->data;
2985
2986 str_len = tipc_link_stats((char *)TLV_DATA(req_tlv_area),
2987 (char *)TLV_DATA(rep_tlv), MAX_LINK_STATS_INFO);
2988 if (!str_len) {
2989 buf_discard(buf);
2990 return tipc_cfg_reply_error_string("link not found");
2991 }
2992
2993 skb_put(buf, TLV_SPACE(str_len));
2994 TLV_SET(rep_tlv, TIPC_TLV_ULTRA_STRING, NULL, str_len);
2995
2996 return buf;
2997 }
2998
2999 /**
3000 * tipc_link_get_max_pkt - get maximum packet size to use when sending to destination
3001 * @dest: network address of destination node
3002 * @selector: used to select from set of active links
3003 *
3004 * If no active link can be found, uses default maximum packet size.
3005 */
3006
3007 u32 tipc_link_get_max_pkt(u32 dest, u32 selector)
3008 {
3009 struct tipc_node *n_ptr;
3010 struct link *l_ptr;
3011 u32 res = MAX_PKT_DEFAULT;
3012
3013 if (dest == tipc_own_addr)
3014 return MAX_MSG_SIZE;
3015
3016 read_lock_bh(&tipc_net_lock);
3017 n_ptr = tipc_node_find(dest);
3018 if (n_ptr) {
3019 tipc_node_lock(n_ptr);
3020 l_ptr = n_ptr->active_links[selector & 1];
3021 if (l_ptr)
3022 res = l_ptr->max_pkt;
3023 tipc_node_unlock(n_ptr);
3024 }
3025 read_unlock_bh(&tipc_net_lock);
3026 return res;
3027 }
3028
3029 static void link_print(struct link *l_ptr, const char *str)
3030 {
3031 char print_area[256];
3032 struct print_buf pb;
3033 struct print_buf *buf = &pb;
3034
3035 tipc_printbuf_init(buf, print_area, sizeof(print_area));
3036
3037 tipc_printf(buf, str);
3038 tipc_printf(buf, "Link %x<%s>:",
3039 l_ptr->addr, l_ptr->b_ptr->name);
3040
3041 #ifdef CONFIG_TIPC_DEBUG
3042 if (link_reset_reset(l_ptr) || link_reset_unknown(l_ptr))
3043 goto print_state;
3044
3045 tipc_printf(buf, ": NXO(%u):", mod(l_ptr->next_out_no));
3046 tipc_printf(buf, "NXI(%u):", mod(l_ptr->next_in_no));
3047 tipc_printf(buf, "SQUE");
3048 if (l_ptr->first_out) {
3049 tipc_printf(buf, "[%u..", msg_seqno(buf_msg(l_ptr->first_out)));
3050 if (l_ptr->next_out)
3051 tipc_printf(buf, "%u..",
3052 msg_seqno(buf_msg(l_ptr->next_out)));
3053 tipc_printf(buf, "%u]", msg_seqno(buf_msg(l_ptr->last_out)));
3054 if ((mod(msg_seqno(buf_msg(l_ptr->last_out)) -
3055 msg_seqno(buf_msg(l_ptr->first_out)))
3056 != (l_ptr->out_queue_size - 1)) ||
3057 (l_ptr->last_out->next != NULL)) {
3058 tipc_printf(buf, "\nSend queue inconsistency\n");
3059 tipc_printf(buf, "first_out= %p ", l_ptr->first_out);
3060 tipc_printf(buf, "next_out= %p ", l_ptr->next_out);
3061 tipc_printf(buf, "last_out= %p ", l_ptr->last_out);
3062 }
3063 } else
3064 tipc_printf(buf, "[]");
3065 tipc_printf(buf, "SQSIZ(%u)", l_ptr->out_queue_size);
3066 if (l_ptr->oldest_deferred_in) {
3067 u32 o = msg_seqno(buf_msg(l_ptr->oldest_deferred_in));
3068 u32 n = msg_seqno(buf_msg(l_ptr->newest_deferred_in));
3069 tipc_printf(buf, ":RQUE[%u..%u]", o, n);
3070 if (l_ptr->deferred_inqueue_sz != mod((n + 1) - o)) {
3071 tipc_printf(buf, ":RQSIZ(%u)",
3072 l_ptr->deferred_inqueue_sz);
3073 }
3074 }
3075 print_state:
3076 #endif
3077
3078 if (link_working_unknown(l_ptr))
3079 tipc_printf(buf, ":WU");
3080 else if (link_reset_reset(l_ptr))
3081 tipc_printf(buf, ":RR");
3082 else if (link_reset_unknown(l_ptr))
3083 tipc_printf(buf, ":RU");
3084 else if (link_working_working(l_ptr))
3085 tipc_printf(buf, ":WW");
3086 tipc_printf(buf, "\n");
3087
3088 tipc_printbuf_validate(buf);
3089 info("%s", print_area);
3090 }
3091