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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
81struct 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
88static void link_handle_out_of_seq_msg(struct link *l_ptr,
89 struct sk_buff *buf);
90static void link_recv_proto_msg(struct link *l_ptr, struct sk_buff *buf);
91static int link_recv_changeover_msg(struct link **l_ptr, struct sk_buff **buf);
92static void link_set_supervision_props(struct link *l_ptr, u32 tolerance);
93static 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);
97static void link_check_defragm_bufs(struct link *l_ptr);
98static void link_state_event(struct link *l_ptr, u32 event);
99static void link_reset_statistics(struct link *l_ptr);
100static void link_print(struct link *l_ptr, const char *str);
101static void link_start(struct link *l_ptr);
102static int link_send_long_buf(struct link *l_ptr, struct sk_buff *buf);
103
104/*
105 * Simple link routines
106 */
107
108static unsigned int align(unsigned int i)
109{
110 return (i + 3) & ~3u;
111}
112
113static 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
130static 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
137static 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
146int 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
153int 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
167static 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
241static 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
290static 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
304struct 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:",
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 is appended to link name by reset/activate */
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->b_ptr = b_ptr;
345 link_set_supervision_props(l_ptr, b_ptr->media->tolerance);
346 l_ptr->state = RESET_UNKNOWN;
347
348 l_ptr->pmsg = (struct tipc_msg *)&l_ptr->proto_msg;
349 msg = l_ptr->pmsg;
350 tipc_msg_init(msg, LINK_PROTOCOL, RESET_MSG, INT_H_SIZE, l_ptr->addr);
351 msg_set_size(msg, sizeof(l_ptr->proto_msg));
352 msg_set_session(msg, (tipc_random & 0xffff));
353 msg_set_bearer_id(msg, b_ptr->identity);
354 strcpy((char *)msg_data(msg), if_name);
355
356 l_ptr->priority = b_ptr->priority;
357 tipc_link_set_queue_limits(l_ptr, b_ptr->media->window);
358
359 link_init_max_pkt(l_ptr);
360
361 l_ptr->next_out_no = 1;
362 INIT_LIST_HEAD(&l_ptr->waiting_ports);
363
364 link_reset_statistics(l_ptr);
365
366 tipc_node_attach_link(n_ptr, l_ptr);
367
368 k_init_timer(&l_ptr->timer, (Handler)link_timeout, (unsigned long)l_ptr);
369 list_add_tail(&l_ptr->link_list, &b_ptr->links);
370 tipc_k_signal((Handler)link_start, (unsigned long)l_ptr);
371
372 return l_ptr;
373}
374
375/**
376 * tipc_link_delete - delete a link
377 * @l_ptr: pointer to link
378 *
379 * Note: 'tipc_net_lock' is write_locked, bearer is locked.
380 * This routine must not grab the node lock until after link timer cancellation
381 * to avoid a potential deadlock situation.
382 */
383
384void tipc_link_delete(struct link *l_ptr)
385{
386 if (!l_ptr) {
387 err("Attempt to delete non-existent link\n");
388 return;
389 }
390
391 k_cancel_timer(&l_ptr->timer);
392
393 tipc_node_lock(l_ptr->owner);
394 tipc_link_reset(l_ptr);
395 tipc_node_detach_link(l_ptr->owner, l_ptr);
396 tipc_link_stop(l_ptr);
397 list_del_init(&l_ptr->link_list);
398 tipc_node_unlock(l_ptr->owner);
399 k_term_timer(&l_ptr->timer);
400 kfree(l_ptr);
401}
402
403static void link_start(struct link *l_ptr)
404{
405 tipc_node_lock(l_ptr->owner);
406 link_state_event(l_ptr, STARTING_EVT);
407 tipc_node_unlock(l_ptr->owner);
408}
409
410/**
411 * link_schedule_port - schedule port for deferred sending
412 * @l_ptr: pointer to link
413 * @origport: reference to sending port
414 * @sz: amount of data to be sent
415 *
416 * Schedules port for renewed sending of messages after link congestion
417 * has abated.
418 */
419
420static int link_schedule_port(struct link *l_ptr, u32 origport, u32 sz)
421{
422 struct tipc_port *p_ptr;
423
424 spin_lock_bh(&tipc_port_list_lock);
425 p_ptr = tipc_port_lock(origport);
426 if (p_ptr) {
427 if (!p_ptr->wakeup)
428 goto exit;
429 if (!list_empty(&p_ptr->wait_list))
430 goto exit;
431 p_ptr->congested = 1;
432 p_ptr->waiting_pkts = 1 + ((sz - 1) / l_ptr->max_pkt);
433 list_add_tail(&p_ptr->wait_list, &l_ptr->waiting_ports);
434 l_ptr->stats.link_congs++;
435exit:
436 tipc_port_unlock(p_ptr);
437 }
438 spin_unlock_bh(&tipc_port_list_lock);
439 return -ELINKCONG;
440}
441
442void tipc_link_wakeup_ports(struct link *l_ptr, int all)
443{
444 struct tipc_port *p_ptr;
445 struct tipc_port *temp_p_ptr;
446 int win = l_ptr->queue_limit[0] - l_ptr->out_queue_size;
447
448 if (all)
449 win = 100000;
450 if (win <= 0)
451 return;
452 if (!spin_trylock_bh(&tipc_port_list_lock))
453 return;
454 if (link_congested(l_ptr))
455 goto exit;
456 list_for_each_entry_safe(p_ptr, temp_p_ptr, &l_ptr->waiting_ports,
457 wait_list) {
458 if (win <= 0)
459 break;
460 list_del_init(&p_ptr->wait_list);
461 spin_lock_bh(p_ptr->lock);
462 p_ptr->congested = 0;
463 p_ptr->wakeup(p_ptr);
464 win -= p_ptr->waiting_pkts;
465 spin_unlock_bh(p_ptr->lock);
466 }
467
468exit:
469 spin_unlock_bh(&tipc_port_list_lock);
470}
471
472/**
473 * link_release_outqueue - purge link's outbound message queue
474 * @l_ptr: pointer to link
475 */
476
477static void link_release_outqueue(struct link *l_ptr)
478{
479 struct sk_buff *buf = l_ptr->first_out;
480 struct sk_buff *next;
481
482 while (buf) {
483 next = buf->next;
484 buf_discard(buf);
485 buf = next;
486 }
487 l_ptr->first_out = NULL;
488 l_ptr->out_queue_size = 0;
489}
490
491/**
492 * tipc_link_reset_fragments - purge link's inbound message fragments queue
493 * @l_ptr: pointer to link
494 */
495
496void tipc_link_reset_fragments(struct link *l_ptr)
497{
498 struct sk_buff *buf = l_ptr->defragm_buf;
499 struct sk_buff *next;
500
501 while (buf) {
502 next = buf->next;
503 buf_discard(buf);
504 buf = next;
505 }
506 l_ptr->defragm_buf = NULL;
507}
508
509/**
510 * tipc_link_stop - purge all inbound and outbound messages associated with link
511 * @l_ptr: pointer to link
512 */
513
514void tipc_link_stop(struct link *l_ptr)
515{
516 struct sk_buff *buf;
517 struct sk_buff *next;
518
519 buf = l_ptr->oldest_deferred_in;
520 while (buf) {
521 next = buf->next;
522 buf_discard(buf);
523 buf = next;
524 }
525
526 buf = l_ptr->first_out;
527 while (buf) {
528 next = buf->next;
529 buf_discard(buf);
530 buf = next;
531 }
532
533 tipc_link_reset_fragments(l_ptr);
534
535 buf_discard(l_ptr->proto_msg_queue);
536 l_ptr->proto_msg_queue = NULL;
537}
538
539/* LINK EVENT CODE IS NOT SUPPORTED AT PRESENT */
540#define link_send_event(fcn, l_ptr, up) do { } while (0)
541
542void tipc_link_reset(struct link *l_ptr)
543{
544 struct sk_buff *buf;
545 u32 prev_state = l_ptr->state;
546 u32 checkpoint = l_ptr->next_in_no;
547 int was_active_link = tipc_link_is_active(l_ptr);
548
549 msg_set_session(l_ptr->pmsg, ((msg_session(l_ptr->pmsg) + 1) & 0xffff));
550
551 /* Link is down, accept any session */
552 l_ptr->peer_session = INVALID_SESSION;
553
554 /* Prepare for max packet size negotiation */
555 link_init_max_pkt(l_ptr);
556
557 l_ptr->state = RESET_UNKNOWN;
558
559 if ((prev_state == RESET_UNKNOWN) || (prev_state == RESET_RESET))
560 return;
561
562 tipc_node_link_down(l_ptr->owner, l_ptr);
563 tipc_bearer_remove_dest(l_ptr->b_ptr, l_ptr->addr);
564
565 if (was_active_link && tipc_node_active_links(l_ptr->owner) &&
566 l_ptr->owner->permit_changeover) {
567 l_ptr->reset_checkpoint = checkpoint;
568 l_ptr->exp_msg_count = START_CHANGEOVER;
569 }
570
571 /* Clean up all queues: */
572
573 link_release_outqueue(l_ptr);
574 buf_discard(l_ptr->proto_msg_queue);
575 l_ptr->proto_msg_queue = NULL;
576 buf = l_ptr->oldest_deferred_in;
577 while (buf) {
578 struct sk_buff *next = buf->next;
579 buf_discard(buf);
580 buf = next;
581 }
582 if (!list_empty(&l_ptr->waiting_ports))
583 tipc_link_wakeup_ports(l_ptr, 1);
584
585 l_ptr->retransm_queue_head = 0;
586 l_ptr->retransm_queue_size = 0;
587 l_ptr->last_out = NULL;
588 l_ptr->first_out = NULL;
589 l_ptr->next_out = NULL;
590 l_ptr->unacked_window = 0;
591 l_ptr->checkpoint = 1;
592 l_ptr->next_out_no = 1;
593 l_ptr->deferred_inqueue_sz = 0;
594 l_ptr->oldest_deferred_in = NULL;
595 l_ptr->newest_deferred_in = NULL;
596 l_ptr->fsm_msg_cnt = 0;
597 l_ptr->stale_count = 0;
598 link_reset_statistics(l_ptr);
599
600 link_send_event(tipc_cfg_link_event, l_ptr, 0);
601 if (!in_own_cluster(l_ptr->addr))
602 link_send_event(tipc_disc_link_event, l_ptr, 0);
603}
604
605
606static void link_activate(struct link *l_ptr)
607{
608 l_ptr->next_in_no = l_ptr->stats.recv_info = 1;
609 tipc_node_link_up(l_ptr->owner, l_ptr);
610 tipc_bearer_add_dest(l_ptr->b_ptr, l_ptr->addr);
611 link_send_event(tipc_cfg_link_event, l_ptr, 1);
612 if (!in_own_cluster(l_ptr->addr))
613 link_send_event(tipc_disc_link_event, l_ptr, 1);
614}
615
616/**
617 * link_state_event - link finite state machine
618 * @l_ptr: pointer to link
619 * @event: state machine event to process
620 */
621
622static void link_state_event(struct link *l_ptr, unsigned event)
623{
624 struct link *other;
625 u32 cont_intv = l_ptr->continuity_interval;
626
627 if (!l_ptr->started && (event != STARTING_EVT))
628 return; /* Not yet. */
629
630 if (link_blocked(l_ptr)) {
631 if (event == TIMEOUT_EVT)
632 link_set_timer(l_ptr, cont_intv);
633 return; /* Changeover going on */
634 }
635
636 switch (l_ptr->state) {
637 case WORKING_WORKING:
638 switch (event) {
639 case TRAFFIC_MSG_EVT:
640 case ACTIVATE_MSG:
641 break;
642 case TIMEOUT_EVT:
643 if (l_ptr->next_in_no != l_ptr->checkpoint) {
644 l_ptr->checkpoint = l_ptr->next_in_no;
645 if (tipc_bclink_acks_missing(l_ptr->owner)) {
646 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
647 0, 0, 0, 0, 0);
648 l_ptr->fsm_msg_cnt++;
649 } else if (l_ptr->max_pkt < l_ptr->max_pkt_target) {
650 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
651 1, 0, 0, 0, 0);
652 l_ptr->fsm_msg_cnt++;
653 }
654 link_set_timer(l_ptr, cont_intv);
655 break;
656 }
657 l_ptr->state = WORKING_UNKNOWN;
658 l_ptr->fsm_msg_cnt = 0;
659 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
660 l_ptr->fsm_msg_cnt++;
661 link_set_timer(l_ptr, cont_intv / 4);
662 break;
663 case RESET_MSG:
664 info("Resetting link <%s>, requested by peer\n",
665 l_ptr->name);
666 tipc_link_reset(l_ptr);
667 l_ptr->state = RESET_RESET;
668 l_ptr->fsm_msg_cnt = 0;
669 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0);
670 l_ptr->fsm_msg_cnt++;
671 link_set_timer(l_ptr, cont_intv);
672 break;
673 default:
674 err("Unknown link event %u in WW state\n", event);
675 }
676 break;
677 case WORKING_UNKNOWN:
678 switch (event) {
679 case TRAFFIC_MSG_EVT:
680 case ACTIVATE_MSG:
681 l_ptr->state = WORKING_WORKING;
682 l_ptr->fsm_msg_cnt = 0;
683 link_set_timer(l_ptr, cont_intv);
684 break;
685 case RESET_MSG:
686 info("Resetting link <%s>, requested by peer "
687 "while probing\n", l_ptr->name);
688 tipc_link_reset(l_ptr);
689 l_ptr->state = RESET_RESET;
690 l_ptr->fsm_msg_cnt = 0;
691 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0);
692 l_ptr->fsm_msg_cnt++;
693 link_set_timer(l_ptr, cont_intv);
694 break;
695 case TIMEOUT_EVT:
696 if (l_ptr->next_in_no != l_ptr->checkpoint) {
697 l_ptr->state = WORKING_WORKING;
698 l_ptr->fsm_msg_cnt = 0;
699 l_ptr->checkpoint = l_ptr->next_in_no;
700 if (tipc_bclink_acks_missing(l_ptr->owner)) {
701 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
702 0, 0, 0, 0, 0);
703 l_ptr->fsm_msg_cnt++;
704 }
705 link_set_timer(l_ptr, cont_intv);
706 } else if (l_ptr->fsm_msg_cnt < l_ptr->abort_limit) {
707 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
708 1, 0, 0, 0, 0);
709 l_ptr->fsm_msg_cnt++;
710 link_set_timer(l_ptr, cont_intv / 4);
711 } else { /* Link has failed */
712 warn("Resetting link <%s>, peer not responding\n",
713 l_ptr->name);
714 tipc_link_reset(l_ptr);
715 l_ptr->state = RESET_UNKNOWN;
716 l_ptr->fsm_msg_cnt = 0;
717 tipc_link_send_proto_msg(l_ptr, RESET_MSG,
718 0, 0, 0, 0, 0);
719 l_ptr->fsm_msg_cnt++;
720 link_set_timer(l_ptr, cont_intv);
721 }
722 break;
723 default:
724 err("Unknown link event %u in WU state\n", event);
725 }
726 break;
727 case RESET_UNKNOWN:
728 switch (event) {
729 case TRAFFIC_MSG_EVT:
730 break;
731 case ACTIVATE_MSG:
732 other = l_ptr->owner->active_links[0];
733 if (other && link_working_unknown(other))
734 break;
735 l_ptr->state = WORKING_WORKING;
736 l_ptr->fsm_msg_cnt = 0;
737 link_activate(l_ptr);
738 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
739 l_ptr->fsm_msg_cnt++;
740 link_set_timer(l_ptr, cont_intv);
741 break;
742 case RESET_MSG:
743 l_ptr->state = RESET_RESET;
744 l_ptr->fsm_msg_cnt = 0;
745 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 1, 0, 0, 0, 0);
746 l_ptr->fsm_msg_cnt++;
747 link_set_timer(l_ptr, cont_intv);
748 break;
749 case STARTING_EVT:
750 l_ptr->started = 1;
751 /* fall through */
752 case TIMEOUT_EVT:
753 tipc_link_send_proto_msg(l_ptr, RESET_MSG, 0, 0, 0, 0, 0);
754 l_ptr->fsm_msg_cnt++;
755 link_set_timer(l_ptr, cont_intv);
756 break;
757 default:
758 err("Unknown link event %u in RU state\n", event);
759 }
760 break;
761 case RESET_RESET:
762 switch (event) {
763 case TRAFFIC_MSG_EVT:
764 case ACTIVATE_MSG:
765 other = l_ptr->owner->active_links[0];
766 if (other && link_working_unknown(other))
767 break;
768 l_ptr->state = WORKING_WORKING;
769 l_ptr->fsm_msg_cnt = 0;
770 link_activate(l_ptr);
771 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
772 l_ptr->fsm_msg_cnt++;
773 link_set_timer(l_ptr, cont_intv);
774 break;
775 case RESET_MSG:
776 break;
777 case TIMEOUT_EVT:
778 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0);
779 l_ptr->fsm_msg_cnt++;
780 link_set_timer(l_ptr, cont_intv);
781 break;
782 default:
783 err("Unknown link event %u in RR state\n", event);
784 }
785 break;
786 default:
787 err("Unknown link state %u/%u\n", l_ptr->state, event);
788 }
789}
790
791/*
792 * link_bundle_buf(): Append contents of a buffer to
793 * the tail of an existing one.
794 */
795
796static int link_bundle_buf(struct link *l_ptr,
797 struct sk_buff *bundler,
798 struct sk_buff *buf)
799{
800 struct tipc_msg *bundler_msg = buf_msg(bundler);
801 struct tipc_msg *msg = buf_msg(buf);
802 u32 size = msg_size(msg);
803 u32 bundle_size = msg_size(bundler_msg);
804 u32 to_pos = align(bundle_size);
805 u32 pad = to_pos - bundle_size;
806
807 if (msg_user(bundler_msg) != MSG_BUNDLER)
808 return 0;
809 if (msg_type(bundler_msg) != OPEN_MSG)
810 return 0;
811 if (skb_tailroom(bundler) < (pad + size))
812 return 0;
813 if (l_ptr->max_pkt < (to_pos + size))
814 return 0;
815
816 skb_put(bundler, pad + size);
817 skb_copy_to_linear_data_offset(bundler, to_pos, buf->data, size);
818 msg_set_size(bundler_msg, to_pos + size);
819 msg_set_msgcnt(bundler_msg, msg_msgcnt(bundler_msg) + 1);
820 buf_discard(buf);
821 l_ptr->stats.sent_bundled++;
822 return 1;
823}
824
825static void link_add_to_outqueue(struct link *l_ptr,
826 struct sk_buff *buf,
827 struct tipc_msg *msg)
828{
829 u32 ack = mod(l_ptr->next_in_no - 1);
830 u32 seqno = mod(l_ptr->next_out_no++);
831
832 msg_set_word(msg, 2, ((ack << 16) | seqno));
833 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
834 buf->next = NULL;
835 if (l_ptr->first_out) {
836 l_ptr->last_out->next = buf;
837 l_ptr->last_out = buf;
838 } else
839 l_ptr->first_out = l_ptr->last_out = buf;
840
841 l_ptr->out_queue_size++;
842 if (l_ptr->out_queue_size > l_ptr->stats.max_queue_sz)
843 l_ptr->stats.max_queue_sz = l_ptr->out_queue_size;
844}
845
846static void link_add_chain_to_outqueue(struct link *l_ptr,
847 struct sk_buff *buf_chain,
848 u32 long_msgno)
849{
850 struct sk_buff *buf;
851 struct tipc_msg *msg;
852
853 if (!l_ptr->next_out)
854 l_ptr->next_out = buf_chain;
855 while (buf_chain) {
856 buf = buf_chain;
857 buf_chain = buf_chain->next;
858
859 msg = buf_msg(buf);
860 msg_set_long_msgno(msg, long_msgno);
861 link_add_to_outqueue(l_ptr, buf, msg);
862 }
863}
864
865/*
866 * tipc_link_send_buf() is the 'full path' for messages, called from
867 * inside TIPC when the 'fast path' in tipc_send_buf
868 * has failed, and from link_send()
869 */
870
871int tipc_link_send_buf(struct link *l_ptr, struct sk_buff *buf)
872{
873 struct tipc_msg *msg = buf_msg(buf);
874 u32 size = msg_size(msg);
875 u32 dsz = msg_data_sz(msg);
876 u32 queue_size = l_ptr->out_queue_size;
877 u32 imp = tipc_msg_tot_importance(msg);
878 u32 queue_limit = l_ptr->queue_limit[imp];
879 u32 max_packet = l_ptr->max_pkt;
880
881 msg_set_prevnode(msg, tipc_own_addr); /* If routed message */
882
883 /* Match msg importance against queue limits: */
884
885 if (unlikely(queue_size >= queue_limit)) {
886 if (imp <= TIPC_CRITICAL_IMPORTANCE) {
887 link_schedule_port(l_ptr, msg_origport(msg), size);
888 buf_discard(buf);
889 return -ELINKCONG;
890 }
891 buf_discard(buf);
892 if (imp > CONN_MANAGER) {
893 warn("Resetting link <%s>, send queue full", l_ptr->name);
894 tipc_link_reset(l_ptr);
895 }
896 return dsz;
897 }
898
899 /* Fragmentation needed ? */
900
901 if (size > max_packet)
902 return link_send_long_buf(l_ptr, buf);
903
904 /* Packet can be queued or sent: */
905
906 if (likely(!tipc_bearer_congested(l_ptr->b_ptr, l_ptr) &&
907 !link_congested(l_ptr))) {
908 link_add_to_outqueue(l_ptr, buf, msg);
909
910 if (likely(tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr))) {
911 l_ptr->unacked_window = 0;
912 } else {
913 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr);
914 l_ptr->stats.bearer_congs++;
915 l_ptr->next_out = buf;
916 }
917 return dsz;
918 }
919 /* Congestion: can message be bundled ?: */
920
921 if ((msg_user(msg) != CHANGEOVER_PROTOCOL) &&
922 (msg_user(msg) != MSG_FRAGMENTER)) {
923
924 /* Try adding message to an existing bundle */
925
926 if (l_ptr->next_out &&
927 link_bundle_buf(l_ptr, l_ptr->last_out, buf)) {
928 tipc_bearer_resolve_congestion(l_ptr->b_ptr, l_ptr);
929 return dsz;
930 }
931
932 /* Try creating a new bundle */
933
934 if (size <= max_packet * 2 / 3) {
935 struct sk_buff *bundler = tipc_buf_acquire(max_packet);
936 struct tipc_msg bundler_hdr;
937
938 if (bundler) {
939 tipc_msg_init(&bundler_hdr, MSG_BUNDLER, OPEN_MSG,
940 INT_H_SIZE, l_ptr->addr);
941 skb_copy_to_linear_data(bundler, &bundler_hdr,
942 INT_H_SIZE);
943 skb_trim(bundler, INT_H_SIZE);
944 link_bundle_buf(l_ptr, bundler, buf);
945 buf = bundler;
946 msg = buf_msg(buf);
947 l_ptr->stats.sent_bundles++;
948 }
949 }
950 }
951 if (!l_ptr->next_out)
952 l_ptr->next_out = buf;
953 link_add_to_outqueue(l_ptr, buf, msg);
954 tipc_bearer_resolve_congestion(l_ptr->b_ptr, l_ptr);
955 return dsz;
956}
957
958/*
959 * tipc_link_send(): same as tipc_link_send_buf(), but the link to use has
960 * not been selected yet, and the the owner node is not locked
961 * Called by TIPC internal users, e.g. the name distributor
962 */
963
964int tipc_link_send(struct sk_buff *buf, u32 dest, u32 selector)
965{
966 struct link *l_ptr;
967 struct tipc_node *n_ptr;
968 int res = -ELINKCONG;
969
970 read_lock_bh(&tipc_net_lock);
971 n_ptr = tipc_node_find(dest);
972 if (n_ptr) {
973 tipc_node_lock(n_ptr);
974 l_ptr = n_ptr->active_links[selector & 1];
975 if (l_ptr)
976 res = tipc_link_send_buf(l_ptr, buf);
977 else
978 buf_discard(buf);
979 tipc_node_unlock(n_ptr);
980 } else {
981 buf_discard(buf);
982 }
983 read_unlock_bh(&tipc_net_lock);
984 return res;
985}
986
987/*
988 * link_send_buf_fast: Entry for data messages where the
989 * destination link is known and the header is complete,
990 * inclusive total message length. Very time critical.
991 * Link is locked. Returns user data length.
992 */
993
994static int link_send_buf_fast(struct link *l_ptr, struct sk_buff *buf,
995 u32 *used_max_pkt)
996{
997 struct tipc_msg *msg = buf_msg(buf);
998 int res = msg_data_sz(msg);
999
1000 if (likely(!link_congested(l_ptr))) {
1001 if (likely(msg_size(msg) <= l_ptr->max_pkt)) {
1002 if (likely(list_empty(&l_ptr->b_ptr->cong_links))) {
1003 link_add_to_outqueue(l_ptr, buf, msg);
1004 if (likely(tipc_bearer_send(l_ptr->b_ptr, buf,
1005 &l_ptr->media_addr))) {
1006 l_ptr->unacked_window = 0;
1007 return res;
1008 }
1009 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr);
1010 l_ptr->stats.bearer_congs++;
1011 l_ptr->next_out = buf;
1012 return res;
1013 }
1014 } else
1015 *used_max_pkt = l_ptr->max_pkt;
1016 }
1017 return tipc_link_send_buf(l_ptr, buf); /* All other cases */
1018}
1019
1020/*
1021 * tipc_send_buf_fast: Entry for data messages where the
1022 * destination node is known and the header is complete,
1023 * inclusive total message length.
1024 * Returns user data length.
1025 */
1026int tipc_send_buf_fast(struct sk_buff *buf, u32 destnode)
1027{
1028 struct link *l_ptr;
1029 struct tipc_node *n_ptr;
1030 int res;
1031 u32 selector = msg_origport(buf_msg(buf)) & 1;
1032 u32 dummy;
1033
1034 if (destnode == tipc_own_addr)
1035 return tipc_port_recv_msg(buf);
1036
1037 read_lock_bh(&tipc_net_lock);
1038 n_ptr = tipc_node_find(destnode);
1039 if (likely(n_ptr)) {
1040 tipc_node_lock(n_ptr);
1041 l_ptr = n_ptr->active_links[selector];
1042 if (likely(l_ptr)) {
1043 res = link_send_buf_fast(l_ptr, buf, &dummy);
1044 tipc_node_unlock(n_ptr);
1045 read_unlock_bh(&tipc_net_lock);
1046 return res;
1047 }
1048 tipc_node_unlock(n_ptr);
1049 }
1050 read_unlock_bh(&tipc_net_lock);
1051 res = msg_data_sz(buf_msg(buf));
1052 tipc_reject_msg(buf, TIPC_ERR_NO_NODE);
1053 return res;
1054}
1055
1056
1057/*
1058 * tipc_link_send_sections_fast: Entry for messages where the
1059 * destination processor is known and the header is complete,
1060 * except for total message length.
1061 * Returns user data length or errno.
1062 */
1063int tipc_link_send_sections_fast(struct tipc_port *sender,
1064 struct iovec const *msg_sect,
1065 const u32 num_sect,
1066 unsigned int total_len,
1067 u32 destaddr)
1068{
1069 struct tipc_msg *hdr = &sender->phdr;
1070 struct link *l_ptr;
1071 struct sk_buff *buf;
1072 struct tipc_node *node;
1073 int res;
1074 u32 selector = msg_origport(hdr) & 1;
1075
1076again:
1077 /*
1078 * Try building message using port's max_pkt hint.
1079 * (Must not hold any locks while building message.)
1080 */
1081
1082 res = tipc_msg_build(hdr, msg_sect, num_sect, total_len,
1083 sender->max_pkt, !sender->user_port, &buf);
1084
1085 read_lock_bh(&tipc_net_lock);
1086 node = tipc_node_find(destaddr);
1087 if (likely(node)) {
1088 tipc_node_lock(node);
1089 l_ptr = node->active_links[selector];
1090 if (likely(l_ptr)) {
1091 if (likely(buf)) {
1092 res = link_send_buf_fast(l_ptr, buf,
1093 &sender->max_pkt);
1094exit:
1095 tipc_node_unlock(node);
1096 read_unlock_bh(&tipc_net_lock);
1097 return res;
1098 }
1099
1100 /* Exit if build request was invalid */
1101
1102 if (unlikely(res < 0))
1103 goto exit;
1104
1105 /* Exit if link (or bearer) is congested */
1106
1107 if (link_congested(l_ptr) ||
1108 !list_empty(&l_ptr->b_ptr->cong_links)) {
1109 res = link_schedule_port(l_ptr,
1110 sender->ref, res);
1111 goto exit;
1112 }
1113
1114 /*
1115 * Message size exceeds max_pkt hint; update hint,
1116 * then re-try fast path or fragment the message
1117 */
1118
1119 sender->max_pkt = l_ptr->max_pkt;
1120 tipc_node_unlock(node);
1121 read_unlock_bh(&tipc_net_lock);
1122
1123
1124 if ((msg_hdr_sz(hdr) + res) <= sender->max_pkt)
1125 goto again;
1126
1127 return link_send_sections_long(sender, msg_sect,
1128 num_sect, total_len,
1129 destaddr);
1130 }
1131 tipc_node_unlock(node);
1132 }
1133 read_unlock_bh(&tipc_net_lock);
1134
1135 /* Couldn't find a link to the destination node */
1136
1137 if (buf)
1138 return tipc_reject_msg(buf, TIPC_ERR_NO_NODE);
1139 if (res >= 0)
1140 return tipc_port_reject_sections(sender, hdr, msg_sect, num_sect,
1141 total_len, TIPC_ERR_NO_NODE);
1142 return res;
1143}
1144
1145/*
1146 * link_send_sections_long(): Entry for long messages where the
1147 * destination node is known and the header is complete,
1148 * inclusive total message length.
1149 * Link and bearer congestion status have been checked to be ok,
1150 * and are ignored if they change.
1151 *
1152 * Note that fragments do not use the full link MTU so that they won't have
1153 * to undergo refragmentation if link changeover causes them to be sent
1154 * over another link with an additional tunnel header added as prefix.
1155 * (Refragmentation will still occur if the other link has a smaller MTU.)
1156 *
1157 * Returns user data length or errno.
1158 */
1159static int link_send_sections_long(struct tipc_port *sender,
1160 struct iovec const *msg_sect,
1161 u32 num_sect,
1162 unsigned int total_len,
1163 u32 destaddr)
1164{
1165 struct link *l_ptr;
1166 struct tipc_node *node;
1167 struct tipc_msg *hdr = &sender->phdr;
1168 u32 dsz = total_len;
1169 u32 max_pkt, fragm_sz, rest;
1170 struct tipc_msg fragm_hdr;
1171 struct sk_buff *buf, *buf_chain, *prev;
1172 u32 fragm_crs, fragm_rest, hsz, sect_rest;
1173 const unchar *sect_crs;
1174 int curr_sect;
1175 u32 fragm_no;
1176
1177again:
1178 fragm_no = 1;
1179 max_pkt = sender->max_pkt - INT_H_SIZE;
1180 /* leave room for tunnel header in case of link changeover */
1181 fragm_sz = max_pkt - INT_H_SIZE;
1182 /* leave room for fragmentation header in each fragment */
1183 rest = dsz;
1184 fragm_crs = 0;
1185 fragm_rest = 0;
1186 sect_rest = 0;
1187 sect_crs = NULL;
1188 curr_sect = -1;
1189
1190 /* Prepare reusable fragment header: */
1191
1192 tipc_msg_init(&fragm_hdr, MSG_FRAGMENTER, FIRST_FRAGMENT,
1193 INT_H_SIZE, msg_destnode(hdr));
1194 msg_set_size(&fragm_hdr, max_pkt);
1195 msg_set_fragm_no(&fragm_hdr, 1);
1196
1197 /* Prepare header of first fragment: */
1198
1199 buf_chain = buf = tipc_buf_acquire(max_pkt);
1200 if (!buf)
1201 return -ENOMEM;
1202 buf->next = NULL;
1203 skb_copy_to_linear_data(buf, &fragm_hdr, INT_H_SIZE);
1204 hsz = msg_hdr_sz(hdr);
1205 skb_copy_to_linear_data_offset(buf, INT_H_SIZE, hdr, hsz);
1206
1207 /* Chop up message: */
1208
1209 fragm_crs = INT_H_SIZE + hsz;
1210 fragm_rest = fragm_sz - hsz;
1211
1212 do { /* For all sections */
1213 u32 sz;
1214
1215 if (!sect_rest) {
1216 sect_rest = msg_sect[++curr_sect].iov_len;
1217 sect_crs = (const unchar *)msg_sect[curr_sect].iov_base;
1218 }
1219
1220 if (sect_rest < fragm_rest)
1221 sz = sect_rest;
1222 else
1223 sz = fragm_rest;
1224
1225 if (likely(!sender->user_port)) {
1226 if (copy_from_user(buf->data + fragm_crs, sect_crs, sz)) {
1227error:
1228 for (; buf_chain; buf_chain = buf) {
1229 buf = buf_chain->next;
1230 buf_discard(buf_chain);
1231 }
1232 return -EFAULT;
1233 }
1234 } else
1235 skb_copy_to_linear_data_offset(buf, fragm_crs,
1236 sect_crs, sz);
1237 sect_crs += sz;
1238 sect_rest -= sz;
1239 fragm_crs += sz;
1240 fragm_rest -= sz;
1241 rest -= sz;
1242
1243 if (!fragm_rest && rest) {
1244
1245 /* Initiate new fragment: */
1246 if (rest <= fragm_sz) {
1247 fragm_sz = rest;
1248 msg_set_type(&fragm_hdr, LAST_FRAGMENT);
1249 } else {
1250 msg_set_type(&fragm_hdr, FRAGMENT);
1251 }
1252 msg_set_size(&fragm_hdr, fragm_sz + INT_H_SIZE);
1253 msg_set_fragm_no(&fragm_hdr, ++fragm_no);
1254 prev = buf;
1255 buf = tipc_buf_acquire(fragm_sz + INT_H_SIZE);
1256 if (!buf)
1257 goto error;
1258
1259 buf->next = NULL;
1260 prev->next = buf;
1261 skb_copy_to_linear_data(buf, &fragm_hdr, INT_H_SIZE);
1262 fragm_crs = INT_H_SIZE;
1263 fragm_rest = fragm_sz;
1264 }
1265 } while (rest > 0);
1266
1267 /*
1268 * Now we have a buffer chain. Select a link and check
1269 * that packet size is still OK
1270 */
1271 node = tipc_node_find(destaddr);
1272 if (likely(node)) {
1273 tipc_node_lock(node);
1274 l_ptr = node->active_links[sender->ref & 1];
1275 if (!l_ptr) {
1276 tipc_node_unlock(node);
1277 goto reject;
1278 }
1279 if (l_ptr->max_pkt < max_pkt) {
1280 sender->max_pkt = l_ptr->max_pkt;
1281 tipc_node_unlock(node);
1282 for (; buf_chain; buf_chain = buf) {
1283 buf = buf_chain->next;
1284 buf_discard(buf_chain);
1285 }
1286 goto again;
1287 }
1288 } else {
1289reject:
1290 for (; buf_chain; buf_chain = buf) {
1291 buf = buf_chain->next;
1292 buf_discard(buf_chain);
1293 }
1294 return tipc_port_reject_sections(sender, hdr, msg_sect, num_sect,
1295 total_len, TIPC_ERR_NO_NODE);
1296 }
1297
1298 /* Append chain of fragments to send queue & send them */
1299
1300 l_ptr->long_msg_seq_no++;
1301 link_add_chain_to_outqueue(l_ptr, buf_chain, l_ptr->long_msg_seq_no);
1302 l_ptr->stats.sent_fragments += fragm_no;
1303 l_ptr->stats.sent_fragmented++;
1304 tipc_link_push_queue(l_ptr);
1305 tipc_node_unlock(node);
1306 return dsz;
1307}
1308
1309/*
1310 * tipc_link_push_packet: Push one unsent packet to the media
1311 */
1312u32 tipc_link_push_packet(struct link *l_ptr)
1313{
1314 struct sk_buff *buf = l_ptr->first_out;
1315 u32 r_q_size = l_ptr->retransm_queue_size;
1316 u32 r_q_head = l_ptr->retransm_queue_head;
1317
1318 /* Step to position where retransmission failed, if any, */
1319 /* consider that buffers may have been released in meantime */
1320
1321 if (r_q_size && buf) {
1322 u32 last = lesser(mod(r_q_head + r_q_size),
1323 link_last_sent(l_ptr));
1324 u32 first = msg_seqno(buf_msg(buf));
1325
1326 while (buf && less(first, r_q_head)) {
1327 first = mod(first + 1);
1328 buf = buf->next;
1329 }
1330 l_ptr->retransm_queue_head = r_q_head = first;
1331 l_ptr->retransm_queue_size = r_q_size = mod(last - first);
1332 }
1333
1334 /* Continue retransmission now, if there is anything: */
1335
1336 if (r_q_size && buf) {
1337 msg_set_ack(buf_msg(buf), mod(l_ptr->next_in_no - 1));
1338 msg_set_bcast_ack(buf_msg(buf), l_ptr->owner->bclink.last_in);
1339 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) {
1340 l_ptr->retransm_queue_head = mod(++r_q_head);
1341 l_ptr->retransm_queue_size = --r_q_size;
1342 l_ptr->stats.retransmitted++;
1343 return 0;
1344 } else {
1345 l_ptr->stats.bearer_congs++;
1346 return PUSH_FAILED;
1347 }
1348 }
1349
1350 /* Send deferred protocol message, if any: */
1351
1352 buf = l_ptr->proto_msg_queue;
1353 if (buf) {
1354 msg_set_ack(buf_msg(buf), mod(l_ptr->next_in_no - 1));
1355 msg_set_bcast_ack(buf_msg(buf), l_ptr->owner->bclink.last_in);
1356 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) {
1357 l_ptr->unacked_window = 0;
1358 buf_discard(buf);
1359 l_ptr->proto_msg_queue = NULL;
1360 return 0;
1361 } else {
1362 l_ptr->stats.bearer_congs++;
1363 return PUSH_FAILED;
1364 }
1365 }
1366
1367 /* Send one deferred data message, if send window not full: */
1368
1369 buf = l_ptr->next_out;
1370 if (buf) {
1371 struct tipc_msg *msg = buf_msg(buf);
1372 u32 next = msg_seqno(msg);
1373 u32 first = msg_seqno(buf_msg(l_ptr->first_out));
1374
1375 if (mod(next - first) < l_ptr->queue_limit[0]) {
1376 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
1377 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1378 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) {
1379 if (msg_user(msg) == MSG_BUNDLER)
1380 msg_set_type(msg, CLOSED_MSG);
1381 l_ptr->next_out = buf->next;
1382 return 0;
1383 } else {
1384 l_ptr->stats.bearer_congs++;
1385 return PUSH_FAILED;
1386 }
1387 }
1388 }
1389 return PUSH_FINISHED;
1390}
1391
1392/*
1393 * push_queue(): push out the unsent messages of a link where
1394 * congestion has abated. Node is locked
1395 */
1396void tipc_link_push_queue(struct link *l_ptr)
1397{
1398 u32 res;
1399
1400 if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr))
1401 return;
1402
1403 do {
1404 res = tipc_link_push_packet(l_ptr);
1405 } while (!res);
1406
1407 if (res == PUSH_FAILED)
1408 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr);
1409}
1410
1411static void link_reset_all(unsigned long addr)
1412{
1413 struct tipc_node *n_ptr;
1414 char addr_string[16];
1415 u32 i;
1416
1417 read_lock_bh(&tipc_net_lock);
1418 n_ptr = tipc_node_find((u32)addr);
1419 if (!n_ptr) {
1420 read_unlock_bh(&tipc_net_lock);
1421 return; /* node no longer exists */
1422 }
1423
1424 tipc_node_lock(n_ptr);
1425
1426 warn("Resetting all links to %s\n",
1427 tipc_addr_string_fill(addr_string, n_ptr->addr));
1428
1429 for (i = 0; i < MAX_BEARERS; i++) {
1430 if (n_ptr->links[i]) {
1431 link_print(n_ptr->links[i], "Resetting link\n");
1432 tipc_link_reset(n_ptr->links[i]);
1433 }
1434 }
1435
1436 tipc_node_unlock(n_ptr);
1437 read_unlock_bh(&tipc_net_lock);
1438}
1439
1440static void link_retransmit_failure(struct link *l_ptr, struct sk_buff *buf)
1441{
1442 struct tipc_msg *msg = buf_msg(buf);
1443
1444 warn("Retransmission failure on link <%s>\n", l_ptr->name);
1445
1446 if (l_ptr->addr) {
1447
1448 /* Handle failure on standard link */
1449
1450 link_print(l_ptr, "Resetting link\n");
1451 tipc_link_reset(l_ptr);
1452
1453 } else {
1454
1455 /* Handle failure on broadcast link */
1456
1457 struct tipc_node *n_ptr;
1458 char addr_string[16];
1459
1460 info("Msg seq number: %u, ", msg_seqno(msg));
1461 info("Outstanding acks: %lu\n",
1462 (unsigned long) TIPC_SKB_CB(buf)->handle);
1463
1464 n_ptr = tipc_bclink_retransmit_to();
1465 tipc_node_lock(n_ptr);
1466
1467 tipc_addr_string_fill(addr_string, n_ptr->addr);
1468 info("Multicast link info for %s\n", addr_string);
1469 info("Supported: %d, ", n_ptr->bclink.supported);
1470 info("Acked: %u\n", n_ptr->bclink.acked);
1471 info("Last in: %u, ", n_ptr->bclink.last_in);
1472 info("Gap after: %u, ", n_ptr->bclink.gap_after);
1473 info("Gap to: %u\n", n_ptr->bclink.gap_to);
1474 info("Nack sync: %u\n\n", n_ptr->bclink.nack_sync);
1475
1476 tipc_k_signal((Handler)link_reset_all, (unsigned long)n_ptr->addr);
1477
1478 tipc_node_unlock(n_ptr);
1479
1480 l_ptr->stale_count = 0;
1481 }
1482}
1483
1484void tipc_link_retransmit(struct link *l_ptr, struct sk_buff *buf,
1485 u32 retransmits)
1486{
1487 struct tipc_msg *msg;
1488
1489 if (!buf)
1490 return;
1491
1492 msg = buf_msg(buf);
1493
1494 if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr)) {
1495 if (l_ptr->retransm_queue_size == 0) {
1496 l_ptr->retransm_queue_head = msg_seqno(msg);
1497 l_ptr->retransm_queue_size = retransmits;
1498 } else {
1499 err("Unexpected retransmit on link %s (qsize=%d)\n",
1500 l_ptr->name, l_ptr->retransm_queue_size);
1501 }
1502 return;
1503 } else {
1504 /* Detect repeated retransmit failures on uncongested bearer */
1505
1506 if (l_ptr->last_retransmitted == msg_seqno(msg)) {
1507 if (++l_ptr->stale_count > 100) {
1508 link_retransmit_failure(l_ptr, buf);
1509 return;
1510 }
1511 } else {
1512 l_ptr->last_retransmitted = msg_seqno(msg);
1513 l_ptr->stale_count = 1;
1514 }
1515 }
1516
1517 while (retransmits && (buf != l_ptr->next_out) && buf) {
1518 msg = buf_msg(buf);
1519 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
1520 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1521 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) {
1522 buf = buf->next;
1523 retransmits--;
1524 l_ptr->stats.retransmitted++;
1525 } else {
1526 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr);
1527 l_ptr->stats.bearer_congs++;
1528 l_ptr->retransm_queue_head = msg_seqno(buf_msg(buf));
1529 l_ptr->retransm_queue_size = retransmits;
1530 return;
1531 }
1532 }
1533
1534 l_ptr->retransm_queue_head = l_ptr->retransm_queue_size = 0;
1535}
1536
1537/**
1538 * link_insert_deferred_queue - insert deferred messages back into receive chain
1539 */
1540
1541static struct sk_buff *link_insert_deferred_queue(struct link *l_ptr,
1542 struct sk_buff *buf)
1543{
1544 u32 seq_no;
1545
1546 if (l_ptr->oldest_deferred_in == NULL)
1547 return buf;
1548
1549 seq_no = msg_seqno(buf_msg(l_ptr->oldest_deferred_in));
1550 if (seq_no == mod(l_ptr->next_in_no)) {
1551 l_ptr->newest_deferred_in->next = buf;
1552 buf = l_ptr->oldest_deferred_in;
1553 l_ptr->oldest_deferred_in = NULL;
1554 l_ptr->deferred_inqueue_sz = 0;
1555 }
1556 return buf;
1557}
1558
1559/**
1560 * link_recv_buf_validate - validate basic format of received message
1561 *
1562 * This routine ensures a TIPC message has an acceptable header, and at least
1563 * as much data as the header indicates it should. The routine also ensures
1564 * that the entire message header is stored in the main fragment of the message
1565 * buffer, to simplify future access to message header fields.
1566 *
1567 * Note: Having extra info present in the message header or data areas is OK.
1568 * TIPC will ignore the excess, under the assumption that it is optional info
1569 * introduced by a later release of the protocol.
1570 */
1571
1572static int link_recv_buf_validate(struct sk_buff *buf)
1573{
1574 static u32 min_data_hdr_size[8] = {
1575 SHORT_H_SIZE, MCAST_H_SIZE, NAMED_H_SIZE, BASIC_H_SIZE,
1576 MAX_H_SIZE, MAX_H_SIZE, MAX_H_SIZE, MAX_H_SIZE
1577 };
1578
1579 struct tipc_msg *msg;
1580 u32 tipc_hdr[2];
1581 u32 size;
1582 u32 hdr_size;
1583 u32 min_hdr_size;
1584
1585 if (unlikely(buf->len < MIN_H_SIZE))
1586 return 0;
1587
1588 msg = skb_header_pointer(buf, 0, sizeof(tipc_hdr), tipc_hdr);
1589 if (msg == NULL)
1590 return 0;
1591
1592 if (unlikely(msg_version(msg) != TIPC_VERSION))
1593 return 0;
1594
1595 size = msg_size(msg);
1596 hdr_size = msg_hdr_sz(msg);
1597 min_hdr_size = msg_isdata(msg) ?
1598 min_data_hdr_size[msg_type(msg)] : INT_H_SIZE;
1599
1600 if (unlikely((hdr_size < min_hdr_size) ||
1601 (size < hdr_size) ||
1602 (buf->len < size) ||
1603 (size - hdr_size > TIPC_MAX_USER_MSG_SIZE)))
1604 return 0;
1605
1606 return pskb_may_pull(buf, hdr_size);
1607}
1608
1609/**
1610 * tipc_recv_msg - process TIPC messages arriving from off-node
1611 * @head: pointer to message buffer chain
1612 * @tb_ptr: pointer to bearer message arrived on
1613 *
1614 * Invoked with no locks held. Bearer pointer must point to a valid bearer
1615 * structure (i.e. cannot be NULL), but bearer can be inactive.
1616 */
1617
1618void tipc_recv_msg(struct sk_buff *head, struct tipc_bearer *b_ptr)
1619{
1620 read_lock_bh(&tipc_net_lock);
1621 while (head) {
1622 struct tipc_node *n_ptr;
1623 struct link *l_ptr;
1624 struct sk_buff *crs;
1625 struct sk_buff *buf = head;
1626 struct tipc_msg *msg;
1627 u32 seq_no;
1628 u32 ackd;
1629 u32 released = 0;
1630 int type;
1631
1632 head = head->next;
1633
1634 /* Ensure bearer is still enabled */
1635
1636 if (unlikely(!b_ptr->active))
1637 goto cont;
1638
1639 /* Ensure message is well-formed */
1640
1641 if (unlikely(!link_recv_buf_validate(buf)))
1642 goto cont;
1643
1644 /* Ensure message data is a single contiguous unit */
1645
1646 if (unlikely(buf_linearize(buf)))
1647 goto cont;
1648
1649 /* Handle arrival of a non-unicast link message */
1650
1651 msg = buf_msg(buf);
1652
1653 if (unlikely(msg_non_seq(msg))) {
1654 if (msg_user(msg) == LINK_CONFIG)
1655 tipc_disc_recv_msg(buf, b_ptr);
1656 else
1657 tipc_bclink_recv_pkt(buf);
1658 continue;
1659 }
1660
1661 if (unlikely(!msg_short(msg) &&
1662 (msg_destnode(msg) != tipc_own_addr)))
1663 goto cont;
1664
1665 /* Discard non-routeable messages destined for another node */
1666
1667 if (unlikely(!msg_isdata(msg) &&
1668 (msg_destnode(msg) != tipc_own_addr))) {
1669 if ((msg_user(msg) != CONN_MANAGER) &&
1670 (msg_user(msg) != MSG_FRAGMENTER))
1671 goto cont;
1672 }
1673
1674 /* Locate neighboring node that sent message */
1675
1676 n_ptr = tipc_node_find(msg_prevnode(msg));
1677 if (unlikely(!n_ptr))
1678 goto cont;
1679 tipc_node_lock(n_ptr);
1680
1681 /* Don't talk to neighbor during cleanup after last session */
1682
1683 if (n_ptr->cleanup_required) {
1684 tipc_node_unlock(n_ptr);
1685 goto cont;
1686 }
1687
1688 /* Locate unicast link endpoint that should handle message */
1689
1690 l_ptr = n_ptr->links[b_ptr->identity];
1691 if (unlikely(!l_ptr)) {
1692 tipc_node_unlock(n_ptr);
1693 goto cont;
1694 }
1695
1696 /* Validate message sequence number info */
1697
1698 seq_no = msg_seqno(msg);
1699 ackd = msg_ack(msg);
1700
1701 /* Release acked messages */
1702
1703 if (less(n_ptr->bclink.acked, msg_bcast_ack(msg))) {
1704 if (tipc_node_is_up(n_ptr) && n_ptr->bclink.supported)
1705 tipc_bclink_acknowledge(n_ptr, msg_bcast_ack(msg));
1706 }
1707
1708 crs = l_ptr->first_out;
1709 while ((crs != l_ptr->next_out) &&
1710 less_eq(msg_seqno(buf_msg(crs)), ackd)) {
1711 struct sk_buff *next = crs->next;
1712
1713 buf_discard(crs);
1714 crs = next;
1715 released++;
1716 }
1717 if (released) {
1718 l_ptr->first_out = crs;
1719 l_ptr->out_queue_size -= released;
1720 }
1721
1722 /* Try sending any messages link endpoint has pending */
1723
1724 if (unlikely(l_ptr->next_out))
1725 tipc_link_push_queue(l_ptr);
1726 if (unlikely(!list_empty(&l_ptr->waiting_ports)))
1727 tipc_link_wakeup_ports(l_ptr, 0);
1728 if (unlikely(++l_ptr->unacked_window >= TIPC_MIN_LINK_WIN)) {
1729 l_ptr->stats.sent_acks++;
1730 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, 0, 0);
1731 }
1732
1733 /* Now (finally!) process the incoming message */
1734
1735protocol_check:
1736 if (likely(link_working_working(l_ptr))) {
1737 if (likely(seq_no == mod(l_ptr->next_in_no))) {
1738 l_ptr->next_in_no++;
1739 if (unlikely(l_ptr->oldest_deferred_in))
1740 head = link_insert_deferred_queue(l_ptr,
1741 head);
1742 if (likely(msg_is_dest(msg, tipc_own_addr))) {
1743deliver:
1744 if (likely(msg_isdata(msg))) {
1745 tipc_node_unlock(n_ptr);
1746 tipc_port_recv_msg(buf);
1747 continue;
1748 }
1749 switch (msg_user(msg)) {
1750 case MSG_BUNDLER:
1751 l_ptr->stats.recv_bundles++;
1752 l_ptr->stats.recv_bundled +=
1753 msg_msgcnt(msg);
1754 tipc_node_unlock(n_ptr);
1755 tipc_link_recv_bundle(buf);
1756 continue;
1757 case NAME_DISTRIBUTOR:
1758 tipc_node_unlock(n_ptr);
1759 tipc_named_recv(buf);
1760 continue;
1761 case CONN_MANAGER:
1762 tipc_node_unlock(n_ptr);
1763 tipc_port_recv_proto_msg(buf);
1764 continue;
1765 case MSG_FRAGMENTER:
1766 l_ptr->stats.recv_fragments++;
1767 if (tipc_link_recv_fragment(&l_ptr->defragm_buf,
1768 &buf, &msg)) {
1769 l_ptr->stats.recv_fragmented++;
1770 goto deliver;
1771 }
1772 break;
1773 case CHANGEOVER_PROTOCOL:
1774 type = msg_type(msg);
1775 if (link_recv_changeover_msg(&l_ptr, &buf)) {
1776 msg = buf_msg(buf);
1777 seq_no = msg_seqno(msg);
1778 if (type == ORIGINAL_MSG)
1779 goto deliver;
1780 goto protocol_check;
1781 }
1782 break;
1783 default:
1784 buf_discard(buf);
1785 buf = NULL;
1786 break;
1787 }
1788 }
1789 tipc_node_unlock(n_ptr);
1790 tipc_net_route_msg(buf);
1791 continue;
1792 }
1793 link_handle_out_of_seq_msg(l_ptr, buf);
1794 head = link_insert_deferred_queue(l_ptr, head);
1795 tipc_node_unlock(n_ptr);
1796 continue;
1797 }
1798
1799 if (msg_user(msg) == LINK_PROTOCOL) {
1800 link_recv_proto_msg(l_ptr, buf);
1801 head = link_insert_deferred_queue(l_ptr, head);
1802 tipc_node_unlock(n_ptr);
1803 continue;
1804 }
1805 link_state_event(l_ptr, TRAFFIC_MSG_EVT);
1806
1807 if (link_working_working(l_ptr)) {
1808 /* Re-insert in front of queue */
1809 buf->next = head;
1810 head = buf;
1811 tipc_node_unlock(n_ptr);
1812 continue;
1813 }
1814 tipc_node_unlock(n_ptr);
1815cont:
1816 buf_discard(buf);
1817 }
1818 read_unlock_bh(&tipc_net_lock);
1819}
1820
1821/*
1822 * link_defer_buf(): Sort a received out-of-sequence packet
1823 * into the deferred reception queue.
1824 * Returns the increase of the queue length,i.e. 0 or 1
1825 */
1826
1827u32 tipc_link_defer_pkt(struct sk_buff **head,
1828 struct sk_buff **tail,
1829 struct sk_buff *buf)
1830{
1831 struct sk_buff *prev = NULL;
1832 struct sk_buff *crs = *head;
1833 u32 seq_no = msg_seqno(buf_msg(buf));
1834
1835 buf->next = NULL;
1836
1837 /* Empty queue ? */
1838 if (*head == NULL) {
1839 *head = *tail = buf;
1840 return 1;
1841 }
1842
1843 /* Last ? */
1844 if (less(msg_seqno(buf_msg(*tail)), seq_no)) {
1845 (*tail)->next = buf;
1846 *tail = buf;
1847 return 1;
1848 }
1849
1850 /* Scan through queue and sort it in */
1851 do {
1852 struct tipc_msg *msg = buf_msg(crs);
1853
1854 if (less(seq_no, msg_seqno(msg))) {
1855 buf->next = crs;
1856 if (prev)
1857 prev->next = buf;
1858 else
1859 *head = buf;
1860 return 1;
1861 }
1862 if (seq_no == msg_seqno(msg))
1863 break;
1864 prev = crs;
1865 crs = crs->next;
1866 } while (crs);
1867
1868 /* Message is a duplicate of an existing message */
1869
1870 buf_discard(buf);
1871 return 0;
1872}
1873
1874/**
1875 * link_handle_out_of_seq_msg - handle arrival of out-of-sequence packet
1876 */
1877
1878static void link_handle_out_of_seq_msg(struct link *l_ptr,
1879 struct sk_buff *buf)
1880{
1881 u32 seq_no = msg_seqno(buf_msg(buf));
1882
1883 if (likely(msg_user(buf_msg(buf)) == LINK_PROTOCOL)) {
1884 link_recv_proto_msg(l_ptr, buf);
1885 return;
1886 }
1887
1888 /* Record OOS packet arrival (force mismatch on next timeout) */
1889
1890 l_ptr->checkpoint--;
1891
1892 /*
1893 * Discard packet if a duplicate; otherwise add it to deferred queue
1894 * and notify peer of gap as per protocol specification
1895 */
1896
1897 if (less(seq_no, mod(l_ptr->next_in_no))) {
1898 l_ptr->stats.duplicates++;
1899 buf_discard(buf);
1900 return;
1901 }
1902
1903 if (tipc_link_defer_pkt(&l_ptr->oldest_deferred_in,
1904 &l_ptr->newest_deferred_in, buf)) {
1905 l_ptr->deferred_inqueue_sz++;
1906 l_ptr->stats.deferred_recv++;
1907 if ((l_ptr->deferred_inqueue_sz % 16) == 1)
1908 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, 0, 0);
1909 } else
1910 l_ptr->stats.duplicates++;
1911}
1912
1913/*
1914 * Send protocol message to the other endpoint.
1915 */
1916void tipc_link_send_proto_msg(struct link *l_ptr, u32 msg_typ, int probe_msg,
1917 u32 gap, u32 tolerance, u32 priority, u32 ack_mtu)
1918{
1919 struct sk_buff *buf = NULL;
1920 struct tipc_msg *msg = l_ptr->pmsg;
1921 u32 msg_size = sizeof(l_ptr->proto_msg);
1922 int r_flag;
1923
1924 if (link_blocked(l_ptr))
1925 return;
1926 msg_set_type(msg, msg_typ);
1927 msg_set_net_plane(msg, l_ptr->b_ptr->net_plane);
1928 msg_set_bcast_ack(msg, mod(l_ptr->owner->bclink.last_in));
1929 msg_set_last_bcast(msg, tipc_bclink_get_last_sent());
1930
1931 if (msg_typ == STATE_MSG) {
1932 u32 next_sent = mod(l_ptr->next_out_no);
1933
1934 if (!tipc_link_is_up(l_ptr))
1935 return;
1936 if (l_ptr->next_out)
1937 next_sent = msg_seqno(buf_msg(l_ptr->next_out));
1938 msg_set_next_sent(msg, next_sent);
1939 if (l_ptr->oldest_deferred_in) {
1940 u32 rec = msg_seqno(buf_msg(l_ptr->oldest_deferred_in));
1941 gap = mod(rec - mod(l_ptr->next_in_no));
1942 }
1943 msg_set_seq_gap(msg, gap);
1944 if (gap)
1945 l_ptr->stats.sent_nacks++;
1946 msg_set_link_tolerance(msg, tolerance);
1947 msg_set_linkprio(msg, priority);
1948 msg_set_max_pkt(msg, ack_mtu);
1949 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
1950 msg_set_probe(msg, probe_msg != 0);
1951 if (probe_msg) {
1952 u32 mtu = l_ptr->max_pkt;
1953
1954 if ((mtu < l_ptr->max_pkt_target) &&
1955 link_working_working(l_ptr) &&
1956 l_ptr->fsm_msg_cnt) {
1957 msg_size = (mtu + (l_ptr->max_pkt_target - mtu)/2 + 2) & ~3;
1958 if (l_ptr->max_pkt_probes == 10) {
1959 l_ptr->max_pkt_target = (msg_size - 4);
1960 l_ptr->max_pkt_probes = 0;
1961 msg_size = (mtu + (l_ptr->max_pkt_target - mtu)/2 + 2) & ~3;
1962 }
1963 l_ptr->max_pkt_probes++;
1964 }
1965
1966 l_ptr->stats.sent_probes++;
1967 }
1968 l_ptr->stats.sent_states++;
1969 } else { /* RESET_MSG or ACTIVATE_MSG */
1970 msg_set_ack(msg, mod(l_ptr->reset_checkpoint - 1));
1971 msg_set_seq_gap(msg, 0);
1972 msg_set_next_sent(msg, 1);
1973 msg_set_probe(msg, 0);
1974 msg_set_link_tolerance(msg, l_ptr->tolerance);
1975 msg_set_linkprio(msg, l_ptr->priority);
1976 msg_set_max_pkt(msg, l_ptr->max_pkt_target);
1977 }
1978
1979 r_flag = (l_ptr->owner->working_links > tipc_link_is_up(l_ptr));
1980 msg_set_redundant_link(msg, r_flag);
1981 msg_set_linkprio(msg, l_ptr->priority);
1982
1983 /* Ensure sequence number will not fit : */
1984
1985 msg_set_seqno(msg, mod(l_ptr->next_out_no + (0xffff/2)));
1986
1987 /* Congestion? */
1988
1989 if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr)) {
1990 if (!l_ptr->proto_msg_queue) {
1991 l_ptr->proto_msg_queue =
1992 tipc_buf_acquire(sizeof(l_ptr->proto_msg));
1993 }
1994 buf = l_ptr->proto_msg_queue;
1995 if (!buf)
1996 return;
1997 skb_copy_to_linear_data(buf, msg, sizeof(l_ptr->proto_msg));
1998 return;
1999 }
2000
2001 /* Message can be sent */
2002
2003 buf = tipc_buf_acquire(msg_size);
2004 if (!buf)
2005 return;
2006
2007 skb_copy_to_linear_data(buf, msg, sizeof(l_ptr->proto_msg));
2008 msg_set_size(buf_msg(buf), msg_size);
2009
2010 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) {
2011 l_ptr->unacked_window = 0;
2012 buf_discard(buf);
2013 return;
2014 }
2015
2016 /* New congestion */
2017 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr);
2018 l_ptr->proto_msg_queue = buf;
2019 l_ptr->stats.bearer_congs++;
2020}
2021
2022/*
2023 * Receive protocol message :
2024 * Note that network plane id propagates through the network, and may
2025 * change at any time. The node with lowest address rules
2026 */
2027
2028static void link_recv_proto_msg(struct link *l_ptr, struct sk_buff *buf)
2029{
2030 u32 rec_gap = 0;
2031 u32 max_pkt_info;
2032 u32 max_pkt_ack;
2033 u32 msg_tol;
2034 struct tipc_msg *msg = buf_msg(buf);
2035
2036 if (link_blocked(l_ptr))
2037 goto exit;
2038
2039 /* record unnumbered packet arrival (force mismatch on next timeout) */
2040
2041 l_ptr->checkpoint--;
2042
2043 if (l_ptr->b_ptr->net_plane != msg_net_plane(msg))
2044 if (tipc_own_addr > msg_prevnode(msg))
2045 l_ptr->b_ptr->net_plane = msg_net_plane(msg);
2046
2047 l_ptr->owner->permit_changeover = msg_redundant_link(msg);
2048
2049 switch (msg_type(msg)) {
2050
2051 case RESET_MSG:
2052 if (!link_working_unknown(l_ptr) &&
2053 (l_ptr->peer_session != INVALID_SESSION)) {
2054 if (msg_session(msg) == l_ptr->peer_session)
2055 break; /* duplicate: ignore */
2056 }
2057 /* fall thru' */
2058 case ACTIVATE_MSG:
2059 /* Update link settings according other endpoint's values */
2060
2061 strcpy((strrchr(l_ptr->name, ':') + 1), (char *)msg_data(msg));
2062
2063 msg_tol = msg_link_tolerance(msg);
2064 if (msg_tol > l_ptr->tolerance)
2065 link_set_supervision_props(l_ptr, msg_tol);
2066
2067 if (msg_linkprio(msg) > l_ptr->priority)
2068 l_ptr->priority = msg_linkprio(msg);
2069
2070 max_pkt_info = msg_max_pkt(msg);
2071 if (max_pkt_info) {
2072 if (max_pkt_info < l_ptr->max_pkt_target)
2073 l_ptr->max_pkt_target = max_pkt_info;
2074 if (l_ptr->max_pkt > l_ptr->max_pkt_target)
2075 l_ptr->max_pkt = l_ptr->max_pkt_target;
2076 } else {
2077 l_ptr->max_pkt = l_ptr->max_pkt_target;
2078 }
2079 l_ptr->owner->bclink.supported = (max_pkt_info != 0);
2080
2081 link_state_event(l_ptr, msg_type(msg));
2082
2083 l_ptr->peer_session = msg_session(msg);
2084 l_ptr->peer_bearer_id = msg_bearer_id(msg);
2085
2086 /* Synchronize broadcast sequence numbers */
2087 if (!tipc_node_redundant_links(l_ptr->owner))
2088 l_ptr->owner->bclink.last_in = mod(msg_last_bcast(msg));
2089 break;
2090 case STATE_MSG:
2091
2092 msg_tol = msg_link_tolerance(msg);
2093 if (msg_tol)
2094 link_set_supervision_props(l_ptr, msg_tol);
2095
2096 if (msg_linkprio(msg) &&
2097 (msg_linkprio(msg) != l_ptr->priority)) {
2098 warn("Resetting link <%s>, priority change %u->%u\n",
2099 l_ptr->name, l_ptr->priority, msg_linkprio(msg));
2100 l_ptr->priority = msg_linkprio(msg);
2101 tipc_link_reset(l_ptr); /* Enforce change to take effect */
2102 break;
2103 }
2104 link_state_event(l_ptr, TRAFFIC_MSG_EVT);
2105 l_ptr->stats.recv_states++;
2106 if (link_reset_unknown(l_ptr))
2107 break;
2108
2109 if (less_eq(mod(l_ptr->next_in_no), msg_next_sent(msg))) {
2110 rec_gap = mod(msg_next_sent(msg) -
2111 mod(l_ptr->next_in_no));
2112 }
2113
2114 max_pkt_ack = msg_max_pkt(msg);
2115 if (max_pkt_ack > l_ptr->max_pkt) {
2116 l_ptr->max_pkt = max_pkt_ack;
2117 l_ptr->max_pkt_probes = 0;
2118 }
2119
2120 max_pkt_ack = 0;
2121 if (msg_probe(msg)) {
2122 l_ptr->stats.recv_probes++;
2123 if (msg_size(msg) > sizeof(l_ptr->proto_msg))
2124 max_pkt_ack = msg_size(msg);
2125 }
2126
2127 /* Protocol message before retransmits, reduce loss risk */
2128
2129 tipc_bclink_check_gap(l_ptr->owner, msg_last_bcast(msg));
2130
2131 if (rec_gap || (msg_probe(msg))) {
2132 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
2133 0, rec_gap, 0, 0, max_pkt_ack);
2134 }
2135 if (msg_seq_gap(msg)) {
2136 l_ptr->stats.recv_nacks++;
2137 tipc_link_retransmit(l_ptr, l_ptr->first_out,
2138 msg_seq_gap(msg));
2139 }
2140 break;
2141 }
2142exit:
2143 buf_discard(buf);
2144}
2145
2146
2147/*
2148 * tipc_link_tunnel(): Send one message via a link belonging to
2149 * another bearer. Owner node is locked.
2150 */
2151static void tipc_link_tunnel(struct link *l_ptr,
2152 struct tipc_msg *tunnel_hdr,
2153 struct tipc_msg *msg,
2154 u32 selector)
2155{
2156 struct link *tunnel;
2157 struct sk_buff *buf;
2158 u32 length = msg_size(msg);
2159
2160 tunnel = l_ptr->owner->active_links[selector & 1];
2161 if (!tipc_link_is_up(tunnel)) {
2162 warn("Link changeover error, "
2163 "tunnel link no longer available\n");
2164 return;
2165 }
2166 msg_set_size(tunnel_hdr, length + INT_H_SIZE);
2167 buf = tipc_buf_acquire(length + INT_H_SIZE);
2168 if (!buf) {
2169 warn("Link changeover error, "
2170 "unable to send tunnel msg\n");
2171 return;
2172 }
2173 skb_copy_to_linear_data(buf, tunnel_hdr, INT_H_SIZE);
2174 skb_copy_to_linear_data_offset(buf, INT_H_SIZE, msg, length);
2175 tipc_link_send_buf(tunnel, buf);
2176}
2177
2178
2179
2180/*
2181 * changeover(): Send whole message queue via the remaining link
2182 * Owner node is locked.
2183 */
2184
2185void tipc_link_changeover(struct link *l_ptr)
2186{
2187 u32 msgcount = l_ptr->out_queue_size;
2188 struct sk_buff *crs = l_ptr->first_out;
2189 struct link *tunnel = l_ptr->owner->active_links[0];
2190 struct tipc_msg tunnel_hdr;
2191 int split_bundles;
2192
2193 if (!tunnel)
2194 return;
2195
2196 if (!l_ptr->owner->permit_changeover) {
2197 warn("Link changeover error, "
2198 "peer did not permit changeover\n");
2199 return;
2200 }
2201
2202 tipc_msg_init(&tunnel_hdr, CHANGEOVER_PROTOCOL,
2203 ORIGINAL_MSG, INT_H_SIZE, l_ptr->addr);
2204 msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id);
2205 msg_set_msgcnt(&tunnel_hdr, msgcount);
2206
2207 if (!l_ptr->first_out) {
2208 struct sk_buff *buf;
2209
2210 buf = tipc_buf_acquire(INT_H_SIZE);
2211 if (buf) {
2212 skb_copy_to_linear_data(buf, &tunnel_hdr, INT_H_SIZE);
2213 msg_set_size(&tunnel_hdr, INT_H_SIZE);
2214 tipc_link_send_buf(tunnel, buf);
2215 } else {
2216 warn("Link changeover error, "
2217 "unable to send changeover msg\n");
2218 }
2219 return;
2220 }
2221
2222 split_bundles = (l_ptr->owner->active_links[0] !=
2223 l_ptr->owner->active_links[1]);
2224
2225 while (crs) {
2226 struct tipc_msg *msg = buf_msg(crs);
2227
2228 if ((msg_user(msg) == MSG_BUNDLER) && split_bundles) {
2229 struct tipc_msg *m = msg_get_wrapped(msg);
2230 unchar *pos = (unchar *)m;
2231
2232 msgcount = msg_msgcnt(msg);
2233 while (msgcount--) {
2234 msg_set_seqno(m, msg_seqno(msg));
2235 tipc_link_tunnel(l_ptr, &tunnel_hdr, m,
2236 msg_link_selector(m));
2237 pos += align(msg_size(m));
2238 m = (struct tipc_msg *)pos;
2239 }
2240 } else {
2241 tipc_link_tunnel(l_ptr, &tunnel_hdr, msg,
2242 msg_link_selector(msg));
2243 }
2244 crs = crs->next;
2245 }
2246}
2247
2248void tipc_link_send_duplicate(struct link *l_ptr, struct link *tunnel)
2249{
2250 struct sk_buff *iter;
2251 struct tipc_msg tunnel_hdr;
2252
2253 tipc_msg_init(&tunnel_hdr, CHANGEOVER_PROTOCOL,
2254 DUPLICATE_MSG, INT_H_SIZE, l_ptr->addr);
2255 msg_set_msgcnt(&tunnel_hdr, l_ptr->out_queue_size);
2256 msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id);
2257 iter = l_ptr->first_out;
2258 while (iter) {
2259 struct sk_buff *outbuf;
2260 struct tipc_msg *msg = buf_msg(iter);
2261 u32 length = msg_size(msg);
2262
2263 if (msg_user(msg) == MSG_BUNDLER)
2264 msg_set_type(msg, CLOSED_MSG);
2265 msg_set_ack(msg, mod(l_ptr->next_in_no - 1)); /* Update */
2266 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
2267 msg_set_size(&tunnel_hdr, length + INT_H_SIZE);
2268 outbuf = tipc_buf_acquire(length + INT_H_SIZE);
2269 if (outbuf == NULL) {
2270 warn("Link changeover error, "
2271 "unable to send duplicate msg\n");
2272 return;
2273 }
2274 skb_copy_to_linear_data(outbuf, &tunnel_hdr, INT_H_SIZE);
2275 skb_copy_to_linear_data_offset(outbuf, INT_H_SIZE, iter->data,
2276 length);
2277 tipc_link_send_buf(tunnel, outbuf);
2278 if (!tipc_link_is_up(l_ptr))
2279 return;
2280 iter = iter->next;
2281 }
2282}
2283
2284
2285
2286/**
2287 * buf_extract - extracts embedded TIPC message from another message
2288 * @skb: encapsulating message buffer
2289 * @from_pos: offset to extract from
2290 *
2291 * Returns a new message buffer containing an embedded message. The
2292 * encapsulating message itself is left unchanged.
2293 */
2294
2295static struct sk_buff *buf_extract(struct sk_buff *skb, u32 from_pos)
2296{
2297 struct tipc_msg *msg = (struct tipc_msg *)(skb->data + from_pos);
2298 u32 size = msg_size(msg);
2299 struct sk_buff *eb;
2300
2301 eb = tipc_buf_acquire(size);
2302 if (eb)
2303 skb_copy_to_linear_data(eb, msg, size);
2304 return eb;
2305}
2306
2307/*
2308 * link_recv_changeover_msg(): Receive tunneled packet sent
2309 * via other link. Node is locked. Return extracted buffer.
2310 */
2311
2312static int link_recv_changeover_msg(struct link **l_ptr,
2313 struct sk_buff **buf)
2314{
2315 struct sk_buff *tunnel_buf = *buf;
2316 struct link *dest_link;
2317 struct tipc_msg *msg;
2318 struct tipc_msg *tunnel_msg = buf_msg(tunnel_buf);
2319 u32 msg_typ = msg_type(tunnel_msg);
2320 u32 msg_count = msg_msgcnt(tunnel_msg);
2321
2322 dest_link = (*l_ptr)->owner->links[msg_bearer_id(tunnel_msg)];
2323 if (!dest_link)
2324 goto exit;
2325 if (dest_link == *l_ptr) {
2326 err("Unexpected changeover message on link <%s>\n",
2327 (*l_ptr)->name);
2328 goto exit;
2329 }
2330 *l_ptr = dest_link;
2331 msg = msg_get_wrapped(tunnel_msg);
2332
2333 if (msg_typ == DUPLICATE_MSG) {
2334 if (less(msg_seqno(msg), mod(dest_link->next_in_no)))
2335 goto exit;
2336 *buf = buf_extract(tunnel_buf, INT_H_SIZE);
2337 if (*buf == NULL) {
2338 warn("Link changeover error, duplicate msg dropped\n");
2339 goto exit;
2340 }
2341 buf_discard(tunnel_buf);
2342 return 1;
2343 }
2344
2345 /* First original message ?: */
2346
2347 if (tipc_link_is_up(dest_link)) {
2348 info("Resetting link <%s>, changeover initiated by peer\n",
2349 dest_link->name);
2350 tipc_link_reset(dest_link);
2351 dest_link->exp_msg_count = msg_count;
2352 if (!msg_count)
2353 goto exit;
2354 } else if (dest_link->exp_msg_count == START_CHANGEOVER) {
2355 dest_link->exp_msg_count = msg_count;
2356 if (!msg_count)
2357 goto exit;
2358 }
2359
2360 /* Receive original message */
2361
2362 if (dest_link->exp_msg_count == 0) {
2363 warn("Link switchover error, "
2364 "got too many tunnelled messages\n");
2365 goto exit;
2366 }
2367 dest_link->exp_msg_count--;
2368 if (less(msg_seqno(msg), dest_link->reset_checkpoint)) {
2369 goto exit;
2370 } else {
2371 *buf = buf_extract(tunnel_buf, INT_H_SIZE);
2372 if (*buf != NULL) {
2373 buf_discard(tunnel_buf);
2374 return 1;
2375 } else {
2376 warn("Link changeover error, original msg dropped\n");
2377 }
2378 }
2379exit:
2380 *buf = NULL;
2381 buf_discard(tunnel_buf);
2382 return 0;
2383}
2384
2385/*
2386 * Bundler functionality:
2387 */
2388void tipc_link_recv_bundle(struct sk_buff *buf)
2389{
2390 u32 msgcount = msg_msgcnt(buf_msg(buf));
2391 u32 pos = INT_H_SIZE;
2392 struct sk_buff *obuf;
2393
2394 while (msgcount--) {
2395 obuf = buf_extract(buf, pos);
2396 if (obuf == NULL) {
2397 warn("Link unable to unbundle message(s)\n");
2398 break;
2399 }
2400 pos += align(msg_size(buf_msg(obuf)));
2401 tipc_net_route_msg(obuf);
2402 }
2403 buf_discard(buf);
2404}
2405
2406/*
2407 * Fragmentation/defragmentation:
2408 */
2409
2410
2411/*
2412 * link_send_long_buf: Entry for buffers needing fragmentation.
2413 * The buffer is complete, inclusive total message length.
2414 * Returns user data length.
2415 */
2416static int link_send_long_buf(struct link *l_ptr, struct sk_buff *buf)
2417{
2418 struct sk_buff *buf_chain = NULL;
2419 struct sk_buff *buf_chain_tail = (struct sk_buff *)&buf_chain;
2420 struct tipc_msg *inmsg = buf_msg(buf);
2421 struct tipc_msg fragm_hdr;
2422 u32 insize = msg_size(inmsg);
2423 u32 dsz = msg_data_sz(inmsg);
2424 unchar *crs = buf->data;
2425 u32 rest = insize;
2426 u32 pack_sz = l_ptr->max_pkt;
2427 u32 fragm_sz = pack_sz - INT_H_SIZE;
2428 u32 fragm_no = 0;
2429 u32 destaddr;
2430
2431 if (msg_short(inmsg))
2432 destaddr = l_ptr->addr;
2433 else
2434 destaddr = msg_destnode(inmsg);
2435
2436 /* Prepare reusable fragment header: */
2437
2438 tipc_msg_init(&fragm_hdr, MSG_FRAGMENTER, FIRST_FRAGMENT,
2439 INT_H_SIZE, destaddr);
2440
2441 /* Chop up message: */
2442
2443 while (rest > 0) {
2444 struct sk_buff *fragm;
2445
2446 if (rest <= fragm_sz) {
2447 fragm_sz = rest;
2448 msg_set_type(&fragm_hdr, LAST_FRAGMENT);
2449 }
2450 fragm = tipc_buf_acquire(fragm_sz + INT_H_SIZE);
2451 if (fragm == NULL) {
2452 buf_discard(buf);
2453 while (buf_chain) {
2454 buf = buf_chain;
2455 buf_chain = buf_chain->next;
2456 buf_discard(buf);
2457 }
2458 return -ENOMEM;
2459 }
2460 msg_set_size(&fragm_hdr, fragm_sz + INT_H_SIZE);
2461 fragm_no++;
2462 msg_set_fragm_no(&fragm_hdr, fragm_no);
2463 skb_copy_to_linear_data(fragm, &fragm_hdr, INT_H_SIZE);
2464 skb_copy_to_linear_data_offset(fragm, INT_H_SIZE, crs,
2465 fragm_sz);
2466 buf_chain_tail->next = fragm;
2467 buf_chain_tail = fragm;
2468
2469 rest -= fragm_sz;
2470 crs += fragm_sz;
2471 msg_set_type(&fragm_hdr, FRAGMENT);
2472 }
2473 buf_discard(buf);
2474
2475 /* Append chain of fragments to send queue & send them */
2476
2477 l_ptr->long_msg_seq_no++;
2478 link_add_chain_to_outqueue(l_ptr, buf_chain, l_ptr->long_msg_seq_no);
2479 l_ptr->stats.sent_fragments += fragm_no;
2480 l_ptr->stats.sent_fragmented++;
2481 tipc_link_push_queue(l_ptr);
2482
2483 return dsz;
2484}
2485
2486/*
2487 * A pending message being re-assembled must store certain values
2488 * to handle subsequent fragments correctly. The following functions
2489 * help storing these values in unused, available fields in the
2490 * pending message. This makes dynamic memory allocation unnecessary.
2491 */
2492
2493static void set_long_msg_seqno(struct sk_buff *buf, u32 seqno)
2494{
2495 msg_set_seqno(buf_msg(buf), seqno);
2496}
2497
2498static u32 get_fragm_size(struct sk_buff *buf)
2499{
2500 return msg_ack(buf_msg(buf));
2501}
2502
2503static void set_fragm_size(struct sk_buff *buf, u32 sz)
2504{
2505 msg_set_ack(buf_msg(buf), sz);
2506}
2507
2508static u32 get_expected_frags(struct sk_buff *buf)
2509{
2510 return msg_bcast_ack(buf_msg(buf));
2511}
2512
2513static void set_expected_frags(struct sk_buff *buf, u32 exp)
2514{
2515 msg_set_bcast_ack(buf_msg(buf), exp);
2516}
2517
2518static u32 get_timer_cnt(struct sk_buff *buf)
2519{
2520 return msg_reroute_cnt(buf_msg(buf));
2521}
2522
2523static void incr_timer_cnt(struct sk_buff *buf)
2524{
2525 msg_incr_reroute_cnt(buf_msg(buf));
2526}
2527
2528/*
2529 * tipc_link_recv_fragment(): Called with node lock on. Returns
2530 * the reassembled buffer if message is complete.
2531 */
2532int tipc_link_recv_fragment(struct sk_buff **pending, struct sk_buff **fb,
2533 struct tipc_msg **m)
2534{
2535 struct sk_buff *prev = NULL;
2536 struct sk_buff *fbuf = *fb;
2537 struct tipc_msg *fragm = buf_msg(fbuf);
2538 struct sk_buff *pbuf = *pending;
2539 u32 long_msg_seq_no = msg_long_msgno(fragm);
2540
2541 *fb = NULL;
2542
2543 /* Is there an incomplete message waiting for this fragment? */
2544
2545 while (pbuf && ((msg_seqno(buf_msg(pbuf)) != long_msg_seq_no) ||
2546 (msg_orignode(fragm) != msg_orignode(buf_msg(pbuf))))) {
2547 prev = pbuf;
2548 pbuf = pbuf->next;
2549 }
2550
2551 if (!pbuf && (msg_type(fragm) == FIRST_FRAGMENT)) {
2552 struct tipc_msg *imsg = (struct tipc_msg *)msg_data(fragm);
2553 u32 msg_sz = msg_size(imsg);
2554 u32 fragm_sz = msg_data_sz(fragm);
2555 u32 exp_fragm_cnt = msg_sz/fragm_sz + !!(msg_sz % fragm_sz);
2556 u32 max = TIPC_MAX_USER_MSG_SIZE + NAMED_H_SIZE;
2557 if (msg_type(imsg) == TIPC_MCAST_MSG)
2558 max = TIPC_MAX_USER_MSG_SIZE + MCAST_H_SIZE;
2559 if (msg_size(imsg) > max) {
2560 buf_discard(fbuf);
2561 return 0;
2562 }
2563 pbuf = tipc_buf_acquire(msg_size(imsg));
2564 if (pbuf != NULL) {
2565 pbuf->next = *pending;
2566 *pending = pbuf;
2567 skb_copy_to_linear_data(pbuf, imsg,
2568 msg_data_sz(fragm));
2569 /* Prepare buffer for subsequent fragments. */
2570
2571 set_long_msg_seqno(pbuf, long_msg_seq_no);
2572 set_fragm_size(pbuf, fragm_sz);
2573 set_expected_frags(pbuf, exp_fragm_cnt - 1);
2574 } else {
2575 warn("Link unable to reassemble fragmented message\n");
2576 }
2577 buf_discard(fbuf);
2578 return 0;
2579 } else if (pbuf && (msg_type(fragm) != FIRST_FRAGMENT)) {
2580 u32 dsz = msg_data_sz(fragm);
2581 u32 fsz = get_fragm_size(pbuf);
2582 u32 crs = ((msg_fragm_no(fragm) - 1) * fsz);
2583 u32 exp_frags = get_expected_frags(pbuf) - 1;
2584 skb_copy_to_linear_data_offset(pbuf, crs,
2585 msg_data(fragm), dsz);
2586 buf_discard(fbuf);
2587
2588 /* Is message complete? */
2589
2590 if (exp_frags == 0) {
2591 if (prev)
2592 prev->next = pbuf->next;
2593 else
2594 *pending = pbuf->next;
2595 msg_reset_reroute_cnt(buf_msg(pbuf));
2596 *fb = pbuf;
2597 *m = buf_msg(pbuf);
2598 return 1;
2599 }
2600 set_expected_frags(pbuf, exp_frags);
2601 return 0;
2602 }
2603 buf_discard(fbuf);
2604 return 0;
2605}
2606
2607/**
2608 * link_check_defragm_bufs - flush stale incoming message fragments
2609 * @l_ptr: pointer to link
2610 */
2611
2612static void link_check_defragm_bufs(struct link *l_ptr)
2613{
2614 struct sk_buff *prev = NULL;
2615 struct sk_buff *next = NULL;
2616 struct sk_buff *buf = l_ptr->defragm_buf;
2617
2618 if (!buf)
2619 return;
2620 if (!link_working_working(l_ptr))
2621 return;
2622 while (buf) {
2623 u32 cnt = get_timer_cnt(buf);
2624
2625 next = buf->next;
2626 if (cnt < 4) {
2627 incr_timer_cnt(buf);
2628 prev = buf;
2629 } else {
2630 if (prev)
2631 prev->next = buf->next;
2632 else
2633 l_ptr->defragm_buf = buf->next;
2634 buf_discard(buf);
2635 }
2636 buf = next;
2637 }
2638}
2639
2640
2641
2642static void link_set_supervision_props(struct link *l_ptr, u32 tolerance)
2643{
2644 if ((tolerance < TIPC_MIN_LINK_TOL) || (tolerance > TIPC_MAX_LINK_TOL))
2645 return;
2646
2647 l_ptr->tolerance = tolerance;
2648 l_ptr->continuity_interval =
2649 ((tolerance / 4) > 500) ? 500 : tolerance / 4;
2650 l_ptr->abort_limit = tolerance / (l_ptr->continuity_interval / 4);
2651}
2652
2653
2654void tipc_link_set_queue_limits(struct link *l_ptr, u32 window)
2655{
2656 /* Data messages from this node, inclusive FIRST_FRAGM */
2657 l_ptr->queue_limit[TIPC_LOW_IMPORTANCE] = window;
2658 l_ptr->queue_limit[TIPC_MEDIUM_IMPORTANCE] = (window / 3) * 4;
2659 l_ptr->queue_limit[TIPC_HIGH_IMPORTANCE] = (window / 3) * 5;
2660 l_ptr->queue_limit[TIPC_CRITICAL_IMPORTANCE] = (window / 3) * 6;
2661 /* Transiting data messages,inclusive FIRST_FRAGM */
2662 l_ptr->queue_limit[TIPC_LOW_IMPORTANCE + 4] = 300;
2663 l_ptr->queue_limit[TIPC_MEDIUM_IMPORTANCE + 4] = 600;
2664 l_ptr->queue_limit[TIPC_HIGH_IMPORTANCE + 4] = 900;
2665 l_ptr->queue_limit[TIPC_CRITICAL_IMPORTANCE + 4] = 1200;
2666 l_ptr->queue_limit[CONN_MANAGER] = 1200;
2667 l_ptr->queue_limit[CHANGEOVER_PROTOCOL] = 2500;
2668 l_ptr->queue_limit[NAME_DISTRIBUTOR] = 3000;
2669 /* FRAGMENT and LAST_FRAGMENT packets */
2670 l_ptr->queue_limit[MSG_FRAGMENTER] = 4000;
2671}
2672
2673/**
2674 * link_find_link - locate link by name
2675 * @name - ptr to link name string
2676 * @node - ptr to area to be filled with ptr to associated node
2677 *
2678 * Caller must hold 'tipc_net_lock' to ensure node and bearer are not deleted;
2679 * this also prevents link deletion.
2680 *
2681 * Returns pointer to link (or 0 if invalid link name).
2682 */
2683
2684static struct link *link_find_link(const char *name, struct tipc_node **node)
2685{
2686 struct link_name link_name_parts;
2687 struct tipc_bearer *b_ptr;
2688 struct link *l_ptr;
2689
2690 if (!link_name_validate(name, &link_name_parts))
2691 return NULL;
2692
2693 b_ptr = tipc_bearer_find_interface(link_name_parts.if_local);
2694 if (!b_ptr)
2695 return NULL;
2696
2697 *node = tipc_node_find(link_name_parts.addr_peer);
2698 if (!*node)
2699 return NULL;
2700
2701 l_ptr = (*node)->links[b_ptr->identity];
2702 if (!l_ptr || strcmp(l_ptr->name, name))
2703 return NULL;
2704
2705 return l_ptr;
2706}
2707
2708struct sk_buff *tipc_link_cmd_config(const void *req_tlv_area, int req_tlv_space,
2709 u16 cmd)
2710{
2711 struct tipc_link_config *args;
2712 u32 new_value;
2713 struct link *l_ptr;
2714 struct tipc_node *node;
2715 int res;
2716
2717 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_CONFIG))
2718 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
2719
2720 args = (struct tipc_link_config *)TLV_DATA(req_tlv_area);
2721 new_value = ntohl(args->value);
2722
2723 if (!strcmp(args->name, tipc_bclink_name)) {
2724 if ((cmd == TIPC_CMD_SET_LINK_WINDOW) &&
2725 (tipc_bclink_set_queue_limits(new_value) == 0))
2726 return tipc_cfg_reply_none();
2727 return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED
2728 " (cannot change setting on broadcast link)");
2729 }
2730
2731 read_lock_bh(&tipc_net_lock);
2732 l_ptr = link_find_link(args->name, &node);
2733 if (!l_ptr) {
2734 read_unlock_bh(&tipc_net_lock);
2735 return tipc_cfg_reply_error_string("link not found");
2736 }
2737
2738 tipc_node_lock(node);
2739 res = -EINVAL;
2740 switch (cmd) {
2741 case TIPC_CMD_SET_LINK_TOL:
2742 if ((new_value >= TIPC_MIN_LINK_TOL) &&
2743 (new_value <= TIPC_MAX_LINK_TOL)) {
2744 link_set_supervision_props(l_ptr, new_value);
2745 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
2746 0, 0, new_value, 0, 0);
2747 res = 0;
2748 }
2749 break;
2750 case TIPC_CMD_SET_LINK_PRI:
2751 if ((new_value >= TIPC_MIN_LINK_PRI) &&
2752 (new_value <= TIPC_MAX_LINK_PRI)) {
2753 l_ptr->priority = new_value;
2754 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
2755 0, 0, 0, new_value, 0);
2756 res = 0;
2757 }
2758 break;
2759 case TIPC_CMD_SET_LINK_WINDOW:
2760 if ((new_value >= TIPC_MIN_LINK_WIN) &&
2761 (new_value <= TIPC_MAX_LINK_WIN)) {
2762 tipc_link_set_queue_limits(l_ptr, new_value);
2763 res = 0;
2764 }
2765 break;
2766 }
2767 tipc_node_unlock(node);
2768
2769 read_unlock_bh(&tipc_net_lock);
2770 if (res)
2771 return tipc_cfg_reply_error_string("cannot change link setting");
2772
2773 return tipc_cfg_reply_none();
2774}
2775
2776/**
2777 * link_reset_statistics - reset link statistics
2778 * @l_ptr: pointer to link
2779 */
2780
2781static void link_reset_statistics(struct link *l_ptr)
2782{
2783 memset(&l_ptr->stats, 0, sizeof(l_ptr->stats));
2784 l_ptr->stats.sent_info = l_ptr->next_out_no;
2785 l_ptr->stats.recv_info = l_ptr->next_in_no;
2786}
2787
2788struct sk_buff *tipc_link_cmd_reset_stats(const void *req_tlv_area, int req_tlv_space)
2789{
2790 char *link_name;
2791 struct link *l_ptr;
2792 struct tipc_node *node;
2793
2794 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_NAME))
2795 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
2796
2797 link_name = (char *)TLV_DATA(req_tlv_area);
2798 if (!strcmp(link_name, tipc_bclink_name)) {
2799 if (tipc_bclink_reset_stats())
2800 return tipc_cfg_reply_error_string("link not found");
2801 return tipc_cfg_reply_none();
2802 }
2803
2804 read_lock_bh(&tipc_net_lock);
2805 l_ptr = link_find_link(link_name, &node);
2806 if (!l_ptr) {
2807 read_unlock_bh(&tipc_net_lock);
2808 return tipc_cfg_reply_error_string("link not found");
2809 }
2810
2811 tipc_node_lock(node);
2812 link_reset_statistics(l_ptr);
2813 tipc_node_unlock(node);
2814 read_unlock_bh(&tipc_net_lock);
2815 return tipc_cfg_reply_none();
2816}
2817
2818/**
2819 * percent - convert count to a percentage of total (rounding up or down)
2820 */
2821
2822static u32 percent(u32 count, u32 total)
2823{
2824 return (count * 100 + (total / 2)) / total;
2825}
2826
2827/**
2828 * tipc_link_stats - print link statistics
2829 * @name: link name
2830 * @buf: print buffer area
2831 * @buf_size: size of print buffer area
2832 *
2833 * Returns length of print buffer data string (or 0 if error)
2834 */
2835
2836static int tipc_link_stats(const char *name, char *buf, const u32 buf_size)
2837{
2838 struct print_buf pb;
2839 struct link *l_ptr;
2840 struct tipc_node *node;
2841 char *status;
2842 u32 profile_total = 0;
2843
2844 if (!strcmp(name, tipc_bclink_name))
2845 return tipc_bclink_stats(buf, buf_size);
2846
2847 tipc_printbuf_init(&pb, buf, buf_size);
2848
2849 read_lock_bh(&tipc_net_lock);
2850 l_ptr = link_find_link(name, &node);
2851 if (!l_ptr) {
2852 read_unlock_bh(&tipc_net_lock);
2853 return 0;
2854 }
2855 tipc_node_lock(node);
2856
2857 if (tipc_link_is_active(l_ptr))
2858 status = "ACTIVE";
2859 else if (tipc_link_is_up(l_ptr))
2860 status = "STANDBY";
2861 else
2862 status = "DEFUNCT";
2863 tipc_printf(&pb, "Link <%s>\n"
2864 " %s MTU:%u Priority:%u Tolerance:%u ms"
2865 " Window:%u packets\n",
2866 l_ptr->name, status, l_ptr->max_pkt,
2867 l_ptr->priority, l_ptr->tolerance, l_ptr->queue_limit[0]);
2868 tipc_printf(&pb, " RX packets:%u fragments:%u/%u bundles:%u/%u\n",
2869 l_ptr->next_in_no - l_ptr->stats.recv_info,
2870 l_ptr->stats.recv_fragments,
2871 l_ptr->stats.recv_fragmented,
2872 l_ptr->stats.recv_bundles,
2873 l_ptr->stats.recv_bundled);
2874 tipc_printf(&pb, " TX packets:%u fragments:%u/%u bundles:%u/%u\n",
2875 l_ptr->next_out_no - l_ptr->stats.sent_info,
2876 l_ptr->stats.sent_fragments,
2877 l_ptr->stats.sent_fragmented,
2878 l_ptr->stats.sent_bundles,
2879 l_ptr->stats.sent_bundled);
2880 profile_total = l_ptr->stats.msg_length_counts;
2881 if (!profile_total)
2882 profile_total = 1;
2883 tipc_printf(&pb, " TX profile sample:%u packets average:%u octets\n"
2884 " 0-64:%u%% -256:%u%% -1024:%u%% -4096:%u%% "
2885 "-16384:%u%% -32768:%u%% -66000:%u%%\n",
2886 l_ptr->stats.msg_length_counts,
2887 l_ptr->stats.msg_lengths_total / profile_total,
2888 percent(l_ptr->stats.msg_length_profile[0], profile_total),
2889 percent(l_ptr->stats.msg_length_profile[1], profile_total),
2890 percent(l_ptr->stats.msg_length_profile[2], profile_total),
2891 percent(l_ptr->stats.msg_length_profile[3], profile_total),
2892 percent(l_ptr->stats.msg_length_profile[4], profile_total),
2893 percent(l_ptr->stats.msg_length_profile[5], profile_total),
2894 percent(l_ptr->stats.msg_length_profile[6], profile_total));
2895 tipc_printf(&pb, " RX states:%u probes:%u naks:%u defs:%u dups:%u\n",
2896 l_ptr->stats.recv_states,
2897 l_ptr->stats.recv_probes,
2898 l_ptr->stats.recv_nacks,
2899 l_ptr->stats.deferred_recv,
2900 l_ptr->stats.duplicates);
2901 tipc_printf(&pb, " TX states:%u probes:%u naks:%u acks:%u dups:%u\n",
2902 l_ptr->stats.sent_states,
2903 l_ptr->stats.sent_probes,
2904 l_ptr->stats.sent_nacks,
2905 l_ptr->stats.sent_acks,
2906 l_ptr->stats.retransmitted);
2907 tipc_printf(&pb, " Congestion bearer:%u link:%u Send queue max:%u avg:%u\n",
2908 l_ptr->stats.bearer_congs,
2909 l_ptr->stats.link_congs,
2910 l_ptr->stats.max_queue_sz,
2911 l_ptr->stats.queue_sz_counts
2912 ? (l_ptr->stats.accu_queue_sz / l_ptr->stats.queue_sz_counts)
2913 : 0);
2914
2915 tipc_node_unlock(node);
2916 read_unlock_bh(&tipc_net_lock);
2917 return tipc_printbuf_validate(&pb);
2918}
2919
2920#define MAX_LINK_STATS_INFO 2000
2921
2922struct sk_buff *tipc_link_cmd_show_stats(const void *req_tlv_area, int req_tlv_space)
2923{
2924 struct sk_buff *buf;
2925 struct tlv_desc *rep_tlv;
2926 int str_len;
2927
2928 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_NAME))
2929 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
2930
2931 buf = tipc_cfg_reply_alloc(TLV_SPACE(MAX_LINK_STATS_INFO));
2932 if (!buf)
2933 return NULL;
2934
2935 rep_tlv = (struct tlv_desc *)buf->data;
2936
2937 str_len = tipc_link_stats((char *)TLV_DATA(req_tlv_area),
2938 (char *)TLV_DATA(rep_tlv), MAX_LINK_STATS_INFO);
2939 if (!str_len) {
2940 buf_discard(buf);
2941 return tipc_cfg_reply_error_string("link not found");
2942 }
2943
2944 skb_put(buf, TLV_SPACE(str_len));
2945 TLV_SET(rep_tlv, TIPC_TLV_ULTRA_STRING, NULL, str_len);
2946
2947 return buf;
2948}
2949
2950/**
2951 * tipc_link_get_max_pkt - get maximum packet size to use when sending to destination
2952 * @dest: network address of destination node
2953 * @selector: used to select from set of active links
2954 *
2955 * If no active link can be found, uses default maximum packet size.
2956 */
2957
2958u32 tipc_link_get_max_pkt(u32 dest, u32 selector)
2959{
2960 struct tipc_node *n_ptr;
2961 struct link *l_ptr;
2962 u32 res = MAX_PKT_DEFAULT;
2963
2964 if (dest == tipc_own_addr)
2965 return MAX_MSG_SIZE;
2966
2967 read_lock_bh(&tipc_net_lock);
2968 n_ptr = tipc_node_find(dest);
2969 if (n_ptr) {
2970 tipc_node_lock(n_ptr);
2971 l_ptr = n_ptr->active_links[selector & 1];
2972 if (l_ptr)
2973 res = l_ptr->max_pkt;
2974 tipc_node_unlock(n_ptr);
2975 }
2976 read_unlock_bh(&tipc_net_lock);
2977 return res;
2978}
2979
2980static void link_print(struct link *l_ptr, const char *str)
2981{
2982 char print_area[256];
2983 struct print_buf pb;
2984 struct print_buf *buf = &pb;
2985
2986 tipc_printbuf_init(buf, print_area, sizeof(print_area));
2987
2988 tipc_printf(buf, str);
2989 tipc_printf(buf, "Link %x<%s>:",
2990 l_ptr->addr, l_ptr->b_ptr->name);
2991
2992#ifdef CONFIG_TIPC_DEBUG
2993 if (link_reset_reset(l_ptr) || link_reset_unknown(l_ptr))
2994 goto print_state;
2995
2996 tipc_printf(buf, ": NXO(%u):", mod(l_ptr->next_out_no));
2997 tipc_printf(buf, "NXI(%u):", mod(l_ptr->next_in_no));
2998 tipc_printf(buf, "SQUE");
2999 if (l_ptr->first_out) {
3000 tipc_printf(buf, "[%u..", msg_seqno(buf_msg(l_ptr->first_out)));
3001 if (l_ptr->next_out)
3002 tipc_printf(buf, "%u..",
3003 msg_seqno(buf_msg(l_ptr->next_out)));
3004 tipc_printf(buf, "%u]", msg_seqno(buf_msg(l_ptr->last_out)));
3005 if ((mod(msg_seqno(buf_msg(l_ptr->last_out)) -
3006 msg_seqno(buf_msg(l_ptr->first_out)))
3007 != (l_ptr->out_queue_size - 1)) ||
3008 (l_ptr->last_out->next != NULL)) {
3009 tipc_printf(buf, "\nSend queue inconsistency\n");
3010 tipc_printf(buf, "first_out= %p ", l_ptr->first_out);
3011 tipc_printf(buf, "next_out= %p ", l_ptr->next_out);
3012 tipc_printf(buf, "last_out= %p ", l_ptr->last_out);
3013 }
3014 } else
3015 tipc_printf(buf, "[]");
3016 tipc_printf(buf, "SQSIZ(%u)", l_ptr->out_queue_size);
3017 if (l_ptr->oldest_deferred_in) {
3018 u32 o = msg_seqno(buf_msg(l_ptr->oldest_deferred_in));
3019 u32 n = msg_seqno(buf_msg(l_ptr->newest_deferred_in));
3020 tipc_printf(buf, ":RQUE[%u..%u]", o, n);
3021 if (l_ptr->deferred_inqueue_sz != mod((n + 1) - o)) {
3022 tipc_printf(buf, ":RQSIZ(%u)",
3023 l_ptr->deferred_inqueue_sz);
3024 }
3025 }
3026print_state:
3027#endif
3028
3029 if (link_working_unknown(l_ptr))
3030 tipc_printf(buf, ":WU");
3031 else if (link_reset_reset(l_ptr))
3032 tipc_printf(buf, ":RR");
3033 else if (link_reset_unknown(l_ptr))
3034 tipc_printf(buf, ":RU");
3035 else if (link_working_working(l_ptr))
3036 tipc_printf(buf, ":WW");
3037 tipc_printf(buf, "\n");
3038
3039 tipc_printbuf_validate(buf);
3040 info("%s", print_area);
3041}
3042
1/*
2 * net/tipc/link.c: TIPC link code
3 *
4 * Copyright (c) 1996-2007, 2012-2016, Ericsson AB
5 * Copyright (c) 2004-2007, 2010-2013, Wind River Systems
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the names of the copyright holders nor the names of its
17 * contributors may be used to endorse or promote products derived from
18 * this software without specific prior written permission.
19 *
20 * Alternatively, this software may be distributed under the terms of the
21 * GNU General Public License ("GPL") version 2 as published by the Free
22 * Software Foundation.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34 * POSSIBILITY OF SUCH DAMAGE.
35 */
36
37#include "core.h"
38#include "subscr.h"
39#include "link.h"
40#include "bcast.h"
41#include "socket.h"
42#include "name_distr.h"
43#include "discover.h"
44#include "netlink.h"
45#include "monitor.h"
46
47#include <linux/pkt_sched.h>
48
49struct tipc_stats {
50 u32 sent_pkts;
51 u32 recv_pkts;
52 u32 sent_states;
53 u32 recv_states;
54 u32 sent_probes;
55 u32 recv_probes;
56 u32 sent_nacks;
57 u32 recv_nacks;
58 u32 sent_acks;
59 u32 sent_bundled;
60 u32 sent_bundles;
61 u32 recv_bundled;
62 u32 recv_bundles;
63 u32 retransmitted;
64 u32 sent_fragmented;
65 u32 sent_fragments;
66 u32 recv_fragmented;
67 u32 recv_fragments;
68 u32 link_congs; /* # port sends blocked by congestion */
69 u32 deferred_recv;
70 u32 duplicates;
71 u32 max_queue_sz; /* send queue size high water mark */
72 u32 accu_queue_sz; /* used for send queue size profiling */
73 u32 queue_sz_counts; /* used for send queue size profiling */
74 u32 msg_length_counts; /* used for message length profiling */
75 u32 msg_lengths_total; /* used for message length profiling */
76 u32 msg_length_profile[7]; /* used for msg. length profiling */
77};
78
79/**
80 * struct tipc_link - TIPC link data structure
81 * @addr: network address of link's peer node
82 * @name: link name character string
83 * @media_addr: media address to use when sending messages over link
84 * @timer: link timer
85 * @net: pointer to namespace struct
86 * @refcnt: reference counter for permanent references (owner node & timer)
87 * @peer_session: link session # being used by peer end of link
88 * @peer_bearer_id: bearer id used by link's peer endpoint
89 * @bearer_id: local bearer id used by link
90 * @tolerance: minimum link continuity loss needed to reset link [in ms]
91 * @abort_limit: # of unacknowledged continuity probes needed to reset link
92 * @state: current state of link FSM
93 * @peer_caps: bitmap describing capabilities of peer node
94 * @silent_intv_cnt: # of timer intervals without any reception from peer
95 * @proto_msg: template for control messages generated by link
96 * @pmsg: convenience pointer to "proto_msg" field
97 * @priority: current link priority
98 * @net_plane: current link network plane ('A' through 'H')
99 * @mon_state: cookie with information needed by link monitor
100 * @backlog_limit: backlog queue congestion thresholds (indexed by importance)
101 * @exp_msg_count: # of tunnelled messages expected during link changeover
102 * @reset_rcv_checkpt: seq # of last acknowledged message at time of link reset
103 * @mtu: current maximum packet size for this link
104 * @advertised_mtu: advertised own mtu when link is being established
105 * @transmitq: queue for sent, non-acked messages
106 * @backlogq: queue for messages waiting to be sent
107 * @snt_nxt: next sequence number to use for outbound messages
108 * @last_retransmitted: sequence number of most recently retransmitted message
109 * @stale_count: # of identical retransmit requests made by peer
110 * @ackers: # of peers that needs to ack each packet before it can be released
111 * @acked: # last packet acked by a certain peer. Used for broadcast.
112 * @rcv_nxt: next sequence number to expect for inbound messages
113 * @deferred_queue: deferred queue saved OOS b'cast message received from node
114 * @unacked_window: # of inbound messages rx'd without ack'ing back to peer
115 * @inputq: buffer queue for messages to be delivered upwards
116 * @namedq: buffer queue for name table messages to be delivered upwards
117 * @next_out: ptr to first unsent outbound message in queue
118 * @wakeupq: linked list of wakeup msgs waiting for link congestion to abate
119 * @long_msg_seq_no: next identifier to use for outbound fragmented messages
120 * @reasm_buf: head of partially reassembled inbound message fragments
121 * @bc_rcvr: marks that this is a broadcast receiver link
122 * @stats: collects statistics regarding link activity
123 */
124struct tipc_link {
125 u32 addr;
126 char name[TIPC_MAX_LINK_NAME];
127 struct net *net;
128
129 /* Management and link supervision data */
130 u32 peer_session;
131 u32 session;
132 u32 peer_bearer_id;
133 u32 bearer_id;
134 u32 tolerance;
135 u32 abort_limit;
136 u32 state;
137 u16 peer_caps;
138 bool active;
139 u32 silent_intv_cnt;
140 char if_name[TIPC_MAX_IF_NAME];
141 u32 priority;
142 char net_plane;
143 struct tipc_mon_state mon_state;
144 u16 rst_cnt;
145
146 /* Failover/synch */
147 u16 drop_point;
148 struct sk_buff *failover_reasm_skb;
149
150 /* Max packet negotiation */
151 u16 mtu;
152 u16 advertised_mtu;
153
154 /* Sending */
155 struct sk_buff_head transmq;
156 struct sk_buff_head backlogq;
157 struct {
158 u16 len;
159 u16 limit;
160 } backlog[5];
161 u16 snd_nxt;
162 u16 last_retransm;
163 u16 window;
164 u32 stale_count;
165
166 /* Reception */
167 u16 rcv_nxt;
168 u32 rcv_unacked;
169 struct sk_buff_head deferdq;
170 struct sk_buff_head *inputq;
171 struct sk_buff_head *namedq;
172
173 /* Congestion handling */
174 struct sk_buff_head wakeupq;
175
176 /* Fragmentation/reassembly */
177 struct sk_buff *reasm_buf;
178
179 /* Broadcast */
180 u16 ackers;
181 u16 acked;
182 struct tipc_link *bc_rcvlink;
183 struct tipc_link *bc_sndlink;
184 unsigned long prev_retr;
185 u16 prev_from;
186 u16 prev_to;
187 u8 nack_state;
188 bool bc_peer_is_up;
189
190 /* Statistics */
191 struct tipc_stats stats;
192};
193
194/*
195 * Error message prefixes
196 */
197static const char *link_co_err = "Link tunneling error, ";
198static const char *link_rst_msg = "Resetting link ";
199
200/* Send states for broadcast NACKs
201 */
202enum {
203 BC_NACK_SND_CONDITIONAL,
204 BC_NACK_SND_UNCONDITIONAL,
205 BC_NACK_SND_SUPPRESS,
206};
207
208#define TIPC_BC_RETR_LIMIT 10 /* [ms] */
209
210/*
211 * Interval between NACKs when packets arrive out of order
212 */
213#define TIPC_NACK_INTV (TIPC_MIN_LINK_WIN * 2)
214
215/* Wildcard value for link session numbers. When it is known that
216 * peer endpoint is down, any session number must be accepted.
217 */
218#define ANY_SESSION 0x10000
219
220/* Link FSM states:
221 */
222enum {
223 LINK_ESTABLISHED = 0xe,
224 LINK_ESTABLISHING = 0xe << 4,
225 LINK_RESET = 0x1 << 8,
226 LINK_RESETTING = 0x2 << 12,
227 LINK_PEER_RESET = 0xd << 16,
228 LINK_FAILINGOVER = 0xf << 20,
229 LINK_SYNCHING = 0xc << 24
230};
231
232/* Link FSM state checking routines
233 */
234static int link_is_up(struct tipc_link *l)
235{
236 return l->state & (LINK_ESTABLISHED | LINK_SYNCHING);
237}
238
239static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
240 struct sk_buff_head *xmitq);
241static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
242 bool probe_reply, u16 rcvgap,
243 int tolerance, int priority,
244 struct sk_buff_head *xmitq);
245static void link_print(struct tipc_link *l, const char *str);
246static int tipc_link_build_nack_msg(struct tipc_link *l,
247 struct sk_buff_head *xmitq);
248static void tipc_link_build_bc_init_msg(struct tipc_link *l,
249 struct sk_buff_head *xmitq);
250static bool tipc_link_release_pkts(struct tipc_link *l, u16 to);
251
252/*
253 * Simple non-static link routines (i.e. referenced outside this file)
254 */
255bool tipc_link_is_up(struct tipc_link *l)
256{
257 return link_is_up(l);
258}
259
260bool tipc_link_peer_is_down(struct tipc_link *l)
261{
262 return l->state == LINK_PEER_RESET;
263}
264
265bool tipc_link_is_reset(struct tipc_link *l)
266{
267 return l->state & (LINK_RESET | LINK_FAILINGOVER | LINK_ESTABLISHING);
268}
269
270bool tipc_link_is_establishing(struct tipc_link *l)
271{
272 return l->state == LINK_ESTABLISHING;
273}
274
275bool tipc_link_is_synching(struct tipc_link *l)
276{
277 return l->state == LINK_SYNCHING;
278}
279
280bool tipc_link_is_failingover(struct tipc_link *l)
281{
282 return l->state == LINK_FAILINGOVER;
283}
284
285bool tipc_link_is_blocked(struct tipc_link *l)
286{
287 return l->state & (LINK_RESETTING | LINK_PEER_RESET | LINK_FAILINGOVER);
288}
289
290static bool link_is_bc_sndlink(struct tipc_link *l)
291{
292 return !l->bc_sndlink;
293}
294
295static bool link_is_bc_rcvlink(struct tipc_link *l)
296{
297 return ((l->bc_rcvlink == l) && !link_is_bc_sndlink(l));
298}
299
300int tipc_link_is_active(struct tipc_link *l)
301{
302 return l->active;
303}
304
305void tipc_link_set_active(struct tipc_link *l, bool active)
306{
307 l->active = active;
308}
309
310u32 tipc_link_id(struct tipc_link *l)
311{
312 return l->peer_bearer_id << 16 | l->bearer_id;
313}
314
315int tipc_link_window(struct tipc_link *l)
316{
317 return l->window;
318}
319
320int tipc_link_prio(struct tipc_link *l)
321{
322 return l->priority;
323}
324
325unsigned long tipc_link_tolerance(struct tipc_link *l)
326{
327 return l->tolerance;
328}
329
330struct sk_buff_head *tipc_link_inputq(struct tipc_link *l)
331{
332 return l->inputq;
333}
334
335char tipc_link_plane(struct tipc_link *l)
336{
337 return l->net_plane;
338}
339
340void tipc_link_add_bc_peer(struct tipc_link *snd_l,
341 struct tipc_link *uc_l,
342 struct sk_buff_head *xmitq)
343{
344 struct tipc_link *rcv_l = uc_l->bc_rcvlink;
345
346 snd_l->ackers++;
347 rcv_l->acked = snd_l->snd_nxt - 1;
348 snd_l->state = LINK_ESTABLISHED;
349 tipc_link_build_bc_init_msg(uc_l, xmitq);
350}
351
352void tipc_link_remove_bc_peer(struct tipc_link *snd_l,
353 struct tipc_link *rcv_l,
354 struct sk_buff_head *xmitq)
355{
356 u16 ack = snd_l->snd_nxt - 1;
357
358 snd_l->ackers--;
359 rcv_l->bc_peer_is_up = true;
360 rcv_l->state = LINK_ESTABLISHED;
361 tipc_link_bc_ack_rcv(rcv_l, ack, xmitq);
362 tipc_link_reset(rcv_l);
363 rcv_l->state = LINK_RESET;
364 if (!snd_l->ackers) {
365 tipc_link_reset(snd_l);
366 snd_l->state = LINK_RESET;
367 __skb_queue_purge(xmitq);
368 }
369}
370
371int tipc_link_bc_peers(struct tipc_link *l)
372{
373 return l->ackers;
374}
375
376u16 link_bc_rcv_gap(struct tipc_link *l)
377{
378 struct sk_buff *skb = skb_peek(&l->deferdq);
379 u16 gap = 0;
380
381 if (more(l->snd_nxt, l->rcv_nxt))
382 gap = l->snd_nxt - l->rcv_nxt;
383 if (skb)
384 gap = buf_seqno(skb) - l->rcv_nxt;
385 return gap;
386}
387
388void tipc_link_set_mtu(struct tipc_link *l, int mtu)
389{
390 l->mtu = mtu;
391}
392
393int tipc_link_mtu(struct tipc_link *l)
394{
395 return l->mtu;
396}
397
398u16 tipc_link_rcv_nxt(struct tipc_link *l)
399{
400 return l->rcv_nxt;
401}
402
403u16 tipc_link_acked(struct tipc_link *l)
404{
405 return l->acked;
406}
407
408char *tipc_link_name(struct tipc_link *l)
409{
410 return l->name;
411}
412
413/**
414 * tipc_link_create - create a new link
415 * @n: pointer to associated node
416 * @if_name: associated interface name
417 * @bearer_id: id (index) of associated bearer
418 * @tolerance: link tolerance to be used by link
419 * @net_plane: network plane (A,B,c..) this link belongs to
420 * @mtu: mtu to be advertised by link
421 * @priority: priority to be used by link
422 * @window: send window to be used by link
423 * @session: session to be used by link
424 * @ownnode: identity of own node
425 * @peer: node id of peer node
426 * @peer_caps: bitmap describing peer node capabilities
427 * @bc_sndlink: the namespace global link used for broadcast sending
428 * @bc_rcvlink: the peer specific link used for broadcast reception
429 * @inputq: queue to put messages ready for delivery
430 * @namedq: queue to put binding table update messages ready for delivery
431 * @link: return value, pointer to put the created link
432 *
433 * Returns true if link was created, otherwise false
434 */
435bool tipc_link_create(struct net *net, char *if_name, int bearer_id,
436 int tolerance, char net_plane, u32 mtu, int priority,
437 int window, u32 session, u32 self,
438 u32 peer, u8 *peer_id, u16 peer_caps,
439 struct tipc_link *bc_sndlink,
440 struct tipc_link *bc_rcvlink,
441 struct sk_buff_head *inputq,
442 struct sk_buff_head *namedq,
443 struct tipc_link **link)
444{
445 char peer_str[NODE_ID_STR_LEN] = {0,};
446 char self_str[NODE_ID_STR_LEN] = {0,};
447 struct tipc_link *l;
448
449 l = kzalloc(sizeof(*l), GFP_ATOMIC);
450 if (!l)
451 return false;
452 *link = l;
453 l->session = session;
454
455 /* Set link name for unicast links only */
456 if (peer_id) {
457 tipc_nodeid2string(self_str, tipc_own_id(net));
458 if (strlen(self_str) > 16)
459 sprintf(self_str, "%x", self);
460 tipc_nodeid2string(peer_str, peer_id);
461 if (strlen(peer_str) > 16)
462 sprintf(peer_str, "%x", peer);
463 }
464 /* Peer i/f name will be completed by reset/activate message */
465 snprintf(l->name, sizeof(l->name), "%s:%s-%s:unknown",
466 self_str, if_name, peer_str);
467
468 strcpy(l->if_name, if_name);
469 l->addr = peer;
470 l->peer_caps = peer_caps;
471 l->net = net;
472 l->peer_session = ANY_SESSION;
473 l->bearer_id = bearer_id;
474 l->tolerance = tolerance;
475 l->net_plane = net_plane;
476 l->advertised_mtu = mtu;
477 l->mtu = mtu;
478 l->priority = priority;
479 tipc_link_set_queue_limits(l, window);
480 l->ackers = 1;
481 l->bc_sndlink = bc_sndlink;
482 l->bc_rcvlink = bc_rcvlink;
483 l->inputq = inputq;
484 l->namedq = namedq;
485 l->state = LINK_RESETTING;
486 __skb_queue_head_init(&l->transmq);
487 __skb_queue_head_init(&l->backlogq);
488 __skb_queue_head_init(&l->deferdq);
489 skb_queue_head_init(&l->wakeupq);
490 skb_queue_head_init(l->inputq);
491 return true;
492}
493
494/**
495 * tipc_link_bc_create - create new link to be used for broadcast
496 * @n: pointer to associated node
497 * @mtu: mtu to be used initially if no peers
498 * @window: send window to be used
499 * @inputq: queue to put messages ready for delivery
500 * @namedq: queue to put binding table update messages ready for delivery
501 * @link: return value, pointer to put the created link
502 *
503 * Returns true if link was created, otherwise false
504 */
505bool tipc_link_bc_create(struct net *net, u32 ownnode, u32 peer,
506 int mtu, int window, u16 peer_caps,
507 struct sk_buff_head *inputq,
508 struct sk_buff_head *namedq,
509 struct tipc_link *bc_sndlink,
510 struct tipc_link **link)
511{
512 struct tipc_link *l;
513
514 if (!tipc_link_create(net, "", MAX_BEARERS, 0, 'Z', mtu, 0, window,
515 0, ownnode, peer, NULL, peer_caps, bc_sndlink,
516 NULL, inputq, namedq, link))
517 return false;
518
519 l = *link;
520 strcpy(l->name, tipc_bclink_name);
521 tipc_link_reset(l);
522 l->state = LINK_RESET;
523 l->ackers = 0;
524 l->bc_rcvlink = l;
525
526 /* Broadcast send link is always up */
527 if (link_is_bc_sndlink(l))
528 l->state = LINK_ESTABLISHED;
529
530 /* Disable replicast if even a single peer doesn't support it */
531 if (link_is_bc_rcvlink(l) && !(peer_caps & TIPC_BCAST_RCAST))
532 tipc_bcast_disable_rcast(net);
533
534 return true;
535}
536
537/**
538 * tipc_link_fsm_evt - link finite state machine
539 * @l: pointer to link
540 * @evt: state machine event to be processed
541 */
542int tipc_link_fsm_evt(struct tipc_link *l, int evt)
543{
544 int rc = 0;
545
546 switch (l->state) {
547 case LINK_RESETTING:
548 switch (evt) {
549 case LINK_PEER_RESET_EVT:
550 l->state = LINK_PEER_RESET;
551 break;
552 case LINK_RESET_EVT:
553 l->state = LINK_RESET;
554 break;
555 case LINK_FAILURE_EVT:
556 case LINK_FAILOVER_BEGIN_EVT:
557 case LINK_ESTABLISH_EVT:
558 case LINK_FAILOVER_END_EVT:
559 case LINK_SYNCH_BEGIN_EVT:
560 case LINK_SYNCH_END_EVT:
561 default:
562 goto illegal_evt;
563 }
564 break;
565 case LINK_RESET:
566 switch (evt) {
567 case LINK_PEER_RESET_EVT:
568 l->state = LINK_ESTABLISHING;
569 break;
570 case LINK_FAILOVER_BEGIN_EVT:
571 l->state = LINK_FAILINGOVER;
572 case LINK_FAILURE_EVT:
573 case LINK_RESET_EVT:
574 case LINK_ESTABLISH_EVT:
575 case LINK_FAILOVER_END_EVT:
576 break;
577 case LINK_SYNCH_BEGIN_EVT:
578 case LINK_SYNCH_END_EVT:
579 default:
580 goto illegal_evt;
581 }
582 break;
583 case LINK_PEER_RESET:
584 switch (evt) {
585 case LINK_RESET_EVT:
586 l->state = LINK_ESTABLISHING;
587 break;
588 case LINK_PEER_RESET_EVT:
589 case LINK_ESTABLISH_EVT:
590 case LINK_FAILURE_EVT:
591 break;
592 case LINK_SYNCH_BEGIN_EVT:
593 case LINK_SYNCH_END_EVT:
594 case LINK_FAILOVER_BEGIN_EVT:
595 case LINK_FAILOVER_END_EVT:
596 default:
597 goto illegal_evt;
598 }
599 break;
600 case LINK_FAILINGOVER:
601 switch (evt) {
602 case LINK_FAILOVER_END_EVT:
603 l->state = LINK_RESET;
604 break;
605 case LINK_PEER_RESET_EVT:
606 case LINK_RESET_EVT:
607 case LINK_ESTABLISH_EVT:
608 case LINK_FAILURE_EVT:
609 break;
610 case LINK_FAILOVER_BEGIN_EVT:
611 case LINK_SYNCH_BEGIN_EVT:
612 case LINK_SYNCH_END_EVT:
613 default:
614 goto illegal_evt;
615 }
616 break;
617 case LINK_ESTABLISHING:
618 switch (evt) {
619 case LINK_ESTABLISH_EVT:
620 l->state = LINK_ESTABLISHED;
621 break;
622 case LINK_FAILOVER_BEGIN_EVT:
623 l->state = LINK_FAILINGOVER;
624 break;
625 case LINK_RESET_EVT:
626 l->state = LINK_RESET;
627 break;
628 case LINK_FAILURE_EVT:
629 case LINK_PEER_RESET_EVT:
630 case LINK_SYNCH_BEGIN_EVT:
631 case LINK_FAILOVER_END_EVT:
632 break;
633 case LINK_SYNCH_END_EVT:
634 default:
635 goto illegal_evt;
636 }
637 break;
638 case LINK_ESTABLISHED:
639 switch (evt) {
640 case LINK_PEER_RESET_EVT:
641 l->state = LINK_PEER_RESET;
642 rc |= TIPC_LINK_DOWN_EVT;
643 break;
644 case LINK_FAILURE_EVT:
645 l->state = LINK_RESETTING;
646 rc |= TIPC_LINK_DOWN_EVT;
647 break;
648 case LINK_RESET_EVT:
649 l->state = LINK_RESET;
650 break;
651 case LINK_ESTABLISH_EVT:
652 case LINK_SYNCH_END_EVT:
653 break;
654 case LINK_SYNCH_BEGIN_EVT:
655 l->state = LINK_SYNCHING;
656 break;
657 case LINK_FAILOVER_BEGIN_EVT:
658 case LINK_FAILOVER_END_EVT:
659 default:
660 goto illegal_evt;
661 }
662 break;
663 case LINK_SYNCHING:
664 switch (evt) {
665 case LINK_PEER_RESET_EVT:
666 l->state = LINK_PEER_RESET;
667 rc |= TIPC_LINK_DOWN_EVT;
668 break;
669 case LINK_FAILURE_EVT:
670 l->state = LINK_RESETTING;
671 rc |= TIPC_LINK_DOWN_EVT;
672 break;
673 case LINK_RESET_EVT:
674 l->state = LINK_RESET;
675 break;
676 case LINK_ESTABLISH_EVT:
677 case LINK_SYNCH_BEGIN_EVT:
678 break;
679 case LINK_SYNCH_END_EVT:
680 l->state = LINK_ESTABLISHED;
681 break;
682 case LINK_FAILOVER_BEGIN_EVT:
683 case LINK_FAILOVER_END_EVT:
684 default:
685 goto illegal_evt;
686 }
687 break;
688 default:
689 pr_err("Unknown FSM state %x in %s\n", l->state, l->name);
690 }
691 return rc;
692illegal_evt:
693 pr_err("Illegal FSM event %x in state %x on link %s\n",
694 evt, l->state, l->name);
695 return rc;
696}
697
698/* link_profile_stats - update statistical profiling of traffic
699 */
700static void link_profile_stats(struct tipc_link *l)
701{
702 struct sk_buff *skb;
703 struct tipc_msg *msg;
704 int length;
705
706 /* Update counters used in statistical profiling of send traffic */
707 l->stats.accu_queue_sz += skb_queue_len(&l->transmq);
708 l->stats.queue_sz_counts++;
709
710 skb = skb_peek(&l->transmq);
711 if (!skb)
712 return;
713 msg = buf_msg(skb);
714 length = msg_size(msg);
715
716 if (msg_user(msg) == MSG_FRAGMENTER) {
717 if (msg_type(msg) != FIRST_FRAGMENT)
718 return;
719 length = msg_size(msg_get_wrapped(msg));
720 }
721 l->stats.msg_lengths_total += length;
722 l->stats.msg_length_counts++;
723 if (length <= 64)
724 l->stats.msg_length_profile[0]++;
725 else if (length <= 256)
726 l->stats.msg_length_profile[1]++;
727 else if (length <= 1024)
728 l->stats.msg_length_profile[2]++;
729 else if (length <= 4096)
730 l->stats.msg_length_profile[3]++;
731 else if (length <= 16384)
732 l->stats.msg_length_profile[4]++;
733 else if (length <= 32768)
734 l->stats.msg_length_profile[5]++;
735 else
736 l->stats.msg_length_profile[6]++;
737}
738
739/* tipc_link_timeout - perform periodic task as instructed from node timeout
740 */
741int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq)
742{
743 int mtyp = 0;
744 int rc = 0;
745 bool state = false;
746 bool probe = false;
747 bool setup = false;
748 u16 bc_snt = l->bc_sndlink->snd_nxt - 1;
749 u16 bc_acked = l->bc_rcvlink->acked;
750 struct tipc_mon_state *mstate = &l->mon_state;
751
752 switch (l->state) {
753 case LINK_ESTABLISHED:
754 case LINK_SYNCHING:
755 mtyp = STATE_MSG;
756 link_profile_stats(l);
757 tipc_mon_get_state(l->net, l->addr, mstate, l->bearer_id);
758 if (mstate->reset || (l->silent_intv_cnt > l->abort_limit))
759 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
760 state = bc_acked != bc_snt;
761 state |= l->bc_rcvlink->rcv_unacked;
762 state |= l->rcv_unacked;
763 state |= !skb_queue_empty(&l->transmq);
764 state |= !skb_queue_empty(&l->deferdq);
765 probe = mstate->probing;
766 probe |= l->silent_intv_cnt;
767 if (probe || mstate->monitoring)
768 l->silent_intv_cnt++;
769 break;
770 case LINK_RESET:
771 setup = l->rst_cnt++ <= 4;
772 setup |= !(l->rst_cnt % 16);
773 mtyp = RESET_MSG;
774 break;
775 case LINK_ESTABLISHING:
776 setup = true;
777 mtyp = ACTIVATE_MSG;
778 break;
779 case LINK_PEER_RESET:
780 case LINK_RESETTING:
781 case LINK_FAILINGOVER:
782 break;
783 default:
784 break;
785 }
786
787 if (state || probe || setup)
788 tipc_link_build_proto_msg(l, mtyp, probe, 0, 0, 0, 0, xmitq);
789
790 return rc;
791}
792
793/**
794 * link_schedule_user - schedule a message sender for wakeup after congestion
795 * @l: congested link
796 * @hdr: header of message that is being sent
797 * Create pseudo msg to send back to user when congestion abates
798 */
799static int link_schedule_user(struct tipc_link *l, struct tipc_msg *hdr)
800{
801 u32 dnode = tipc_own_addr(l->net);
802 u32 dport = msg_origport(hdr);
803 struct sk_buff *skb;
804
805 /* Create and schedule wakeup pseudo message */
806 skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0,
807 dnode, l->addr, dport, 0, 0);
808 if (!skb)
809 return -ENOBUFS;
810 msg_set_dest_droppable(buf_msg(skb), true);
811 TIPC_SKB_CB(skb)->chain_imp = msg_importance(hdr);
812 skb_queue_tail(&l->wakeupq, skb);
813 l->stats.link_congs++;
814 return -ELINKCONG;
815}
816
817/**
818 * link_prepare_wakeup - prepare users for wakeup after congestion
819 * @l: congested link
820 * Wake up a number of waiting users, as permitted by available space
821 * in the send queue
822 */
823void link_prepare_wakeup(struct tipc_link *l)
824{
825 struct sk_buff *skb, *tmp;
826 int imp, i = 0;
827
828 skb_queue_walk_safe(&l->wakeupq, skb, tmp) {
829 imp = TIPC_SKB_CB(skb)->chain_imp;
830 if (l->backlog[imp].len < l->backlog[imp].limit) {
831 skb_unlink(skb, &l->wakeupq);
832 skb_queue_tail(l->inputq, skb);
833 } else if (i++ > 10) {
834 break;
835 }
836 }
837}
838
839void tipc_link_reset(struct tipc_link *l)
840{
841 l->peer_session = ANY_SESSION;
842 l->session++;
843 l->mtu = l->advertised_mtu;
844 __skb_queue_purge(&l->transmq);
845 __skb_queue_purge(&l->deferdq);
846 skb_queue_splice_init(&l->wakeupq, l->inputq);
847 __skb_queue_purge(&l->backlogq);
848 l->backlog[TIPC_LOW_IMPORTANCE].len = 0;
849 l->backlog[TIPC_MEDIUM_IMPORTANCE].len = 0;
850 l->backlog[TIPC_HIGH_IMPORTANCE].len = 0;
851 l->backlog[TIPC_CRITICAL_IMPORTANCE].len = 0;
852 l->backlog[TIPC_SYSTEM_IMPORTANCE].len = 0;
853 kfree_skb(l->reasm_buf);
854 kfree_skb(l->failover_reasm_skb);
855 l->reasm_buf = NULL;
856 l->failover_reasm_skb = NULL;
857 l->rcv_unacked = 0;
858 l->snd_nxt = 1;
859 l->rcv_nxt = 1;
860 l->acked = 0;
861 l->silent_intv_cnt = 0;
862 l->rst_cnt = 0;
863 l->stale_count = 0;
864 l->bc_peer_is_up = false;
865 memset(&l->mon_state, 0, sizeof(l->mon_state));
866 tipc_link_reset_stats(l);
867}
868
869/**
870 * tipc_link_xmit(): enqueue buffer list according to queue situation
871 * @link: link to use
872 * @list: chain of buffers containing message
873 * @xmitq: returned list of packets to be sent by caller
874 *
875 * Consumes the buffer chain.
876 * Returns 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS
877 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted
878 */
879int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list,
880 struct sk_buff_head *xmitq)
881{
882 struct tipc_msg *hdr = buf_msg(skb_peek(list));
883 unsigned int maxwin = l->window;
884 int imp = msg_importance(hdr);
885 unsigned int mtu = l->mtu;
886 u16 ack = l->rcv_nxt - 1;
887 u16 seqno = l->snd_nxt;
888 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
889 struct sk_buff_head *transmq = &l->transmq;
890 struct sk_buff_head *backlogq = &l->backlogq;
891 struct sk_buff *skb, *_skb, *bskb;
892 int pkt_cnt = skb_queue_len(list);
893 int rc = 0;
894
895 if (unlikely(msg_size(hdr) > mtu)) {
896 skb_queue_purge(list);
897 return -EMSGSIZE;
898 }
899
900 /* Allow oversubscription of one data msg per source at congestion */
901 if (unlikely(l->backlog[imp].len >= l->backlog[imp].limit)) {
902 if (imp == TIPC_SYSTEM_IMPORTANCE) {
903 pr_warn("%s<%s>, link overflow", link_rst_msg, l->name);
904 return -ENOBUFS;
905 }
906 rc = link_schedule_user(l, hdr);
907 }
908
909 if (pkt_cnt > 1) {
910 l->stats.sent_fragmented++;
911 l->stats.sent_fragments += pkt_cnt;
912 }
913
914 /* Prepare each packet for sending, and add to relevant queue: */
915 while (skb_queue_len(list)) {
916 skb = skb_peek(list);
917 hdr = buf_msg(skb);
918 msg_set_seqno(hdr, seqno);
919 msg_set_ack(hdr, ack);
920 msg_set_bcast_ack(hdr, bc_ack);
921
922 if (likely(skb_queue_len(transmq) < maxwin)) {
923 _skb = skb_clone(skb, GFP_ATOMIC);
924 if (!_skb) {
925 skb_queue_purge(list);
926 return -ENOBUFS;
927 }
928 __skb_dequeue(list);
929 __skb_queue_tail(transmq, skb);
930 __skb_queue_tail(xmitq, _skb);
931 TIPC_SKB_CB(skb)->ackers = l->ackers;
932 l->rcv_unacked = 0;
933 l->stats.sent_pkts++;
934 seqno++;
935 continue;
936 }
937 if (tipc_msg_bundle(skb_peek_tail(backlogq), hdr, mtu)) {
938 kfree_skb(__skb_dequeue(list));
939 l->stats.sent_bundled++;
940 continue;
941 }
942 if (tipc_msg_make_bundle(&bskb, hdr, mtu, l->addr)) {
943 kfree_skb(__skb_dequeue(list));
944 __skb_queue_tail(backlogq, bskb);
945 l->backlog[msg_importance(buf_msg(bskb))].len++;
946 l->stats.sent_bundled++;
947 l->stats.sent_bundles++;
948 continue;
949 }
950 l->backlog[imp].len += skb_queue_len(list);
951 skb_queue_splice_tail_init(list, backlogq);
952 }
953 l->snd_nxt = seqno;
954 return rc;
955}
956
957void tipc_link_advance_backlog(struct tipc_link *l, struct sk_buff_head *xmitq)
958{
959 struct sk_buff *skb, *_skb;
960 struct tipc_msg *hdr;
961 u16 seqno = l->snd_nxt;
962 u16 ack = l->rcv_nxt - 1;
963 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
964
965 while (skb_queue_len(&l->transmq) < l->window) {
966 skb = skb_peek(&l->backlogq);
967 if (!skb)
968 break;
969 _skb = skb_clone(skb, GFP_ATOMIC);
970 if (!_skb)
971 break;
972 __skb_dequeue(&l->backlogq);
973 hdr = buf_msg(skb);
974 l->backlog[msg_importance(hdr)].len--;
975 __skb_queue_tail(&l->transmq, skb);
976 __skb_queue_tail(xmitq, _skb);
977 TIPC_SKB_CB(skb)->ackers = l->ackers;
978 msg_set_seqno(hdr, seqno);
979 msg_set_ack(hdr, ack);
980 msg_set_bcast_ack(hdr, bc_ack);
981 l->rcv_unacked = 0;
982 l->stats.sent_pkts++;
983 seqno++;
984 }
985 l->snd_nxt = seqno;
986}
987
988static void link_retransmit_failure(struct tipc_link *l, struct sk_buff *skb)
989{
990 struct tipc_msg *hdr = buf_msg(skb);
991
992 pr_warn("Retransmission failure on link <%s>\n", l->name);
993 link_print(l, "State of link ");
994 pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n",
995 msg_user(hdr), msg_type(hdr), msg_size(hdr), msg_errcode(hdr));
996 pr_info("sqno %u, prev: %x, src: %x\n",
997 msg_seqno(hdr), msg_prevnode(hdr), msg_orignode(hdr));
998}
999
1000int tipc_link_retrans(struct tipc_link *l, struct tipc_link *nacker,
1001 u16 from, u16 to, struct sk_buff_head *xmitq)
1002{
1003 struct sk_buff *_skb, *skb = skb_peek(&l->transmq);
1004 struct tipc_msg *hdr;
1005 u16 ack = l->rcv_nxt - 1;
1006 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1007
1008 if (!skb)
1009 return 0;
1010
1011 /* Detect repeated retransmit failures on same packet */
1012 if (nacker->last_retransm != buf_seqno(skb)) {
1013 nacker->last_retransm = buf_seqno(skb);
1014 nacker->stale_count = 1;
1015 } else if (++nacker->stale_count > 100) {
1016 link_retransmit_failure(l, skb);
1017 nacker->stale_count = 0;
1018 if (link_is_bc_sndlink(l))
1019 return TIPC_LINK_DOWN_EVT;
1020 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1021 }
1022
1023 /* Move forward to where retransmission should start */
1024 skb_queue_walk(&l->transmq, skb) {
1025 if (!less(buf_seqno(skb), from))
1026 break;
1027 }
1028
1029 skb_queue_walk_from(&l->transmq, skb) {
1030 if (more(buf_seqno(skb), to))
1031 break;
1032 hdr = buf_msg(skb);
1033 _skb = __pskb_copy(skb, MIN_H_SIZE, GFP_ATOMIC);
1034 if (!_skb)
1035 return 0;
1036 hdr = buf_msg(_skb);
1037 msg_set_ack(hdr, ack);
1038 msg_set_bcast_ack(hdr, bc_ack);
1039 _skb->priority = TC_PRIO_CONTROL;
1040 __skb_queue_tail(xmitq, _skb);
1041 l->stats.retransmitted++;
1042 }
1043 return 0;
1044}
1045
1046/* tipc_data_input - deliver data and name distr msgs to upper layer
1047 *
1048 * Consumes buffer if message is of right type
1049 * Node lock must be held
1050 */
1051static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb,
1052 struct sk_buff_head *inputq)
1053{
1054 struct sk_buff_head *mc_inputq = l->bc_rcvlink->inputq;
1055 struct tipc_msg *hdr = buf_msg(skb);
1056
1057 switch (msg_user(hdr)) {
1058 case TIPC_LOW_IMPORTANCE:
1059 case TIPC_MEDIUM_IMPORTANCE:
1060 case TIPC_HIGH_IMPORTANCE:
1061 case TIPC_CRITICAL_IMPORTANCE:
1062 if (unlikely(msg_in_group(hdr) || msg_mcast(hdr))) {
1063 skb_queue_tail(mc_inputq, skb);
1064 return true;
1065 }
1066 case CONN_MANAGER:
1067 skb_queue_tail(inputq, skb);
1068 return true;
1069 case GROUP_PROTOCOL:
1070 skb_queue_tail(mc_inputq, skb);
1071 return true;
1072 case NAME_DISTRIBUTOR:
1073 l->bc_rcvlink->state = LINK_ESTABLISHED;
1074 skb_queue_tail(l->namedq, skb);
1075 return true;
1076 case MSG_BUNDLER:
1077 case TUNNEL_PROTOCOL:
1078 case MSG_FRAGMENTER:
1079 case BCAST_PROTOCOL:
1080 return false;
1081 default:
1082 pr_warn("Dropping received illegal msg type\n");
1083 kfree_skb(skb);
1084 return false;
1085 };
1086}
1087
1088/* tipc_link_input - process packet that has passed link protocol check
1089 *
1090 * Consumes buffer
1091 */
1092static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb,
1093 struct sk_buff_head *inputq)
1094{
1095 struct tipc_msg *hdr = buf_msg(skb);
1096 struct sk_buff **reasm_skb = &l->reasm_buf;
1097 struct sk_buff *iskb;
1098 struct sk_buff_head tmpq;
1099 int usr = msg_user(hdr);
1100 int rc = 0;
1101 int pos = 0;
1102 int ipos = 0;
1103
1104 if (unlikely(usr == TUNNEL_PROTOCOL)) {
1105 if (msg_type(hdr) == SYNCH_MSG) {
1106 __skb_queue_purge(&l->deferdq);
1107 goto drop;
1108 }
1109 if (!tipc_msg_extract(skb, &iskb, &ipos))
1110 return rc;
1111 kfree_skb(skb);
1112 skb = iskb;
1113 hdr = buf_msg(skb);
1114 if (less(msg_seqno(hdr), l->drop_point))
1115 goto drop;
1116 if (tipc_data_input(l, skb, inputq))
1117 return rc;
1118 usr = msg_user(hdr);
1119 reasm_skb = &l->failover_reasm_skb;
1120 }
1121
1122 if (usr == MSG_BUNDLER) {
1123 skb_queue_head_init(&tmpq);
1124 l->stats.recv_bundles++;
1125 l->stats.recv_bundled += msg_msgcnt(hdr);
1126 while (tipc_msg_extract(skb, &iskb, &pos))
1127 tipc_data_input(l, iskb, &tmpq);
1128 tipc_skb_queue_splice_tail(&tmpq, inputq);
1129 return 0;
1130 } else if (usr == MSG_FRAGMENTER) {
1131 l->stats.recv_fragments++;
1132 if (tipc_buf_append(reasm_skb, &skb)) {
1133 l->stats.recv_fragmented++;
1134 tipc_data_input(l, skb, inputq);
1135 } else if (!*reasm_skb && !link_is_bc_rcvlink(l)) {
1136 pr_warn_ratelimited("Unable to build fragment list\n");
1137 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1138 }
1139 return 0;
1140 } else if (usr == BCAST_PROTOCOL) {
1141 tipc_bcast_lock(l->net);
1142 tipc_link_bc_init_rcv(l->bc_rcvlink, hdr);
1143 tipc_bcast_unlock(l->net);
1144 }
1145drop:
1146 kfree_skb(skb);
1147 return 0;
1148}
1149
1150static bool tipc_link_release_pkts(struct tipc_link *l, u16 acked)
1151{
1152 bool released = false;
1153 struct sk_buff *skb, *tmp;
1154
1155 skb_queue_walk_safe(&l->transmq, skb, tmp) {
1156 if (more(buf_seqno(skb), acked))
1157 break;
1158 __skb_unlink(skb, &l->transmq);
1159 kfree_skb(skb);
1160 released = true;
1161 }
1162 return released;
1163}
1164
1165/* tipc_link_build_state_msg: prepare link state message for transmission
1166 *
1167 * Note that sending of broadcast ack is coordinated among nodes, to reduce
1168 * risk of ack storms towards the sender
1169 */
1170int tipc_link_build_state_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1171{
1172 if (!l)
1173 return 0;
1174
1175 /* Broadcast ACK must be sent via a unicast link => defer to caller */
1176 if (link_is_bc_rcvlink(l)) {
1177 if (((l->rcv_nxt ^ tipc_own_addr(l->net)) & 0xf) != 0xf)
1178 return 0;
1179 l->rcv_unacked = 0;
1180
1181 /* Use snd_nxt to store peer's snd_nxt in broadcast rcv link */
1182 l->snd_nxt = l->rcv_nxt;
1183 return TIPC_LINK_SND_STATE;
1184 }
1185
1186 /* Unicast ACK */
1187 l->rcv_unacked = 0;
1188 l->stats.sent_acks++;
1189 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, 0, xmitq);
1190 return 0;
1191}
1192
1193/* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message
1194 */
1195void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1196{
1197 int mtyp = RESET_MSG;
1198 struct sk_buff *skb;
1199
1200 if (l->state == LINK_ESTABLISHING)
1201 mtyp = ACTIVATE_MSG;
1202
1203 tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, 0, xmitq);
1204
1205 /* Inform peer that this endpoint is going down if applicable */
1206 skb = skb_peek_tail(xmitq);
1207 if (skb && (l->state == LINK_RESET))
1208 msg_set_peer_stopping(buf_msg(skb), 1);
1209}
1210
1211/* tipc_link_build_nack_msg: prepare link nack message for transmission
1212 * Note that sending of broadcast NACK is coordinated among nodes, to
1213 * reduce the risk of NACK storms towards the sender
1214 */
1215static int tipc_link_build_nack_msg(struct tipc_link *l,
1216 struct sk_buff_head *xmitq)
1217{
1218 u32 def_cnt = ++l->stats.deferred_recv;
1219 int match1, match2;
1220
1221 if (link_is_bc_rcvlink(l)) {
1222 match1 = def_cnt & 0xf;
1223 match2 = tipc_own_addr(l->net) & 0xf;
1224 if (match1 == match2)
1225 return TIPC_LINK_SND_STATE;
1226 return 0;
1227 }
1228
1229 if ((skb_queue_len(&l->deferdq) == 1) || !(def_cnt % TIPC_NACK_INTV))
1230 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, 0, xmitq);
1231 return 0;
1232}
1233
1234/* tipc_link_rcv - process TIPC packets/messages arriving from off-node
1235 * @l: the link that should handle the message
1236 * @skb: TIPC packet
1237 * @xmitq: queue to place packets to be sent after this call
1238 */
1239int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb,
1240 struct sk_buff_head *xmitq)
1241{
1242 struct sk_buff_head *defq = &l->deferdq;
1243 struct tipc_msg *hdr;
1244 u16 seqno, rcv_nxt, win_lim;
1245 int rc = 0;
1246
1247 do {
1248 hdr = buf_msg(skb);
1249 seqno = msg_seqno(hdr);
1250 rcv_nxt = l->rcv_nxt;
1251 win_lim = rcv_nxt + TIPC_MAX_LINK_WIN;
1252
1253 /* Verify and update link state */
1254 if (unlikely(msg_user(hdr) == LINK_PROTOCOL))
1255 return tipc_link_proto_rcv(l, skb, xmitq);
1256
1257 if (unlikely(!link_is_up(l))) {
1258 if (l->state == LINK_ESTABLISHING)
1259 rc = TIPC_LINK_UP_EVT;
1260 goto drop;
1261 }
1262
1263 /* Don't send probe at next timeout expiration */
1264 l->silent_intv_cnt = 0;
1265
1266 /* Drop if outside receive window */
1267 if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) {
1268 l->stats.duplicates++;
1269 goto drop;
1270 }
1271
1272 /* Forward queues and wake up waiting users */
1273 if (likely(tipc_link_release_pkts(l, msg_ack(hdr)))) {
1274 tipc_link_advance_backlog(l, xmitq);
1275 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1276 link_prepare_wakeup(l);
1277 }
1278
1279 /* Defer delivery if sequence gap */
1280 if (unlikely(seqno != rcv_nxt)) {
1281 __tipc_skb_queue_sorted(defq, seqno, skb);
1282 rc |= tipc_link_build_nack_msg(l, xmitq);
1283 break;
1284 }
1285
1286 /* Deliver packet */
1287 l->rcv_nxt++;
1288 l->stats.recv_pkts++;
1289 if (!tipc_data_input(l, skb, l->inputq))
1290 rc |= tipc_link_input(l, skb, l->inputq);
1291 if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN))
1292 rc |= tipc_link_build_state_msg(l, xmitq);
1293 if (unlikely(rc & ~TIPC_LINK_SND_STATE))
1294 break;
1295 } while ((skb = __skb_dequeue(defq)));
1296
1297 return rc;
1298drop:
1299 kfree_skb(skb);
1300 return rc;
1301}
1302
1303static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
1304 bool probe_reply, u16 rcvgap,
1305 int tolerance, int priority,
1306 struct sk_buff_head *xmitq)
1307{
1308 struct tipc_link *bcl = l->bc_rcvlink;
1309 struct sk_buff *skb;
1310 struct tipc_msg *hdr;
1311 struct sk_buff_head *dfq = &l->deferdq;
1312 bool node_up = link_is_up(bcl);
1313 struct tipc_mon_state *mstate = &l->mon_state;
1314 int dlen = 0;
1315 void *data;
1316
1317 /* Don't send protocol message during reset or link failover */
1318 if (tipc_link_is_blocked(l))
1319 return;
1320
1321 if (!tipc_link_is_up(l) && (mtyp == STATE_MSG))
1322 return;
1323
1324 if (!skb_queue_empty(dfq))
1325 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1326
1327 skb = tipc_msg_create(LINK_PROTOCOL, mtyp, INT_H_SIZE,
1328 tipc_max_domain_size, l->addr,
1329 tipc_own_addr(l->net), 0, 0, 0);
1330 if (!skb)
1331 return;
1332
1333 hdr = buf_msg(skb);
1334 data = msg_data(hdr);
1335 msg_set_session(hdr, l->session);
1336 msg_set_bearer_id(hdr, l->bearer_id);
1337 msg_set_net_plane(hdr, l->net_plane);
1338 msg_set_next_sent(hdr, l->snd_nxt);
1339 msg_set_ack(hdr, l->rcv_nxt - 1);
1340 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
1341 msg_set_bc_ack_invalid(hdr, !node_up);
1342 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
1343 msg_set_link_tolerance(hdr, tolerance);
1344 msg_set_linkprio(hdr, priority);
1345 msg_set_redundant_link(hdr, node_up);
1346 msg_set_seq_gap(hdr, 0);
1347 msg_set_seqno(hdr, l->snd_nxt + U16_MAX / 2);
1348
1349 if (mtyp == STATE_MSG) {
1350 msg_set_seq_gap(hdr, rcvgap);
1351 msg_set_bc_gap(hdr, link_bc_rcv_gap(bcl));
1352 msg_set_probe(hdr, probe);
1353 msg_set_is_keepalive(hdr, probe || probe_reply);
1354 tipc_mon_prep(l->net, data, &dlen, mstate, l->bearer_id);
1355 msg_set_size(hdr, INT_H_SIZE + dlen);
1356 skb_trim(skb, INT_H_SIZE + dlen);
1357 l->stats.sent_states++;
1358 l->rcv_unacked = 0;
1359 } else {
1360 /* RESET_MSG or ACTIVATE_MSG */
1361 msg_set_max_pkt(hdr, l->advertised_mtu);
1362 strcpy(data, l->if_name);
1363 msg_set_size(hdr, INT_H_SIZE + TIPC_MAX_IF_NAME);
1364 skb_trim(skb, INT_H_SIZE + TIPC_MAX_IF_NAME);
1365 }
1366 if (probe)
1367 l->stats.sent_probes++;
1368 if (rcvgap)
1369 l->stats.sent_nacks++;
1370 skb->priority = TC_PRIO_CONTROL;
1371 __skb_queue_tail(xmitq, skb);
1372}
1373
1374/* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets
1375 * with contents of the link's transmit and backlog queues.
1376 */
1377void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
1378 int mtyp, struct sk_buff_head *xmitq)
1379{
1380 struct sk_buff *skb, *tnlskb;
1381 struct tipc_msg *hdr, tnlhdr;
1382 struct sk_buff_head *queue = &l->transmq;
1383 struct sk_buff_head tmpxq, tnlq;
1384 u16 pktlen, pktcnt, seqno = l->snd_nxt;
1385
1386 if (!tnl)
1387 return;
1388
1389 skb_queue_head_init(&tnlq);
1390 skb_queue_head_init(&tmpxq);
1391
1392 /* At least one packet required for safe algorithm => add dummy */
1393 skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1394 BASIC_H_SIZE, 0, l->addr, tipc_own_addr(l->net),
1395 0, 0, TIPC_ERR_NO_PORT);
1396 if (!skb) {
1397 pr_warn("%sunable to create tunnel packet\n", link_co_err);
1398 return;
1399 }
1400 skb_queue_tail(&tnlq, skb);
1401 tipc_link_xmit(l, &tnlq, &tmpxq);
1402 __skb_queue_purge(&tmpxq);
1403
1404 /* Initialize reusable tunnel packet header */
1405 tipc_msg_init(tipc_own_addr(l->net), &tnlhdr, TUNNEL_PROTOCOL,
1406 mtyp, INT_H_SIZE, l->addr);
1407 pktcnt = skb_queue_len(&l->transmq) + skb_queue_len(&l->backlogq);
1408 msg_set_msgcnt(&tnlhdr, pktcnt);
1409 msg_set_bearer_id(&tnlhdr, l->peer_bearer_id);
1410tnl:
1411 /* Wrap each packet into a tunnel packet */
1412 skb_queue_walk(queue, skb) {
1413 hdr = buf_msg(skb);
1414 if (queue == &l->backlogq)
1415 msg_set_seqno(hdr, seqno++);
1416 pktlen = msg_size(hdr);
1417 msg_set_size(&tnlhdr, pktlen + INT_H_SIZE);
1418 tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE, GFP_ATOMIC);
1419 if (!tnlskb) {
1420 pr_warn("%sunable to send packet\n", link_co_err);
1421 return;
1422 }
1423 skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE);
1424 skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen);
1425 __skb_queue_tail(&tnlq, tnlskb);
1426 }
1427 if (queue != &l->backlogq) {
1428 queue = &l->backlogq;
1429 goto tnl;
1430 }
1431
1432 tipc_link_xmit(tnl, &tnlq, xmitq);
1433
1434 if (mtyp == FAILOVER_MSG) {
1435 tnl->drop_point = l->rcv_nxt;
1436 tnl->failover_reasm_skb = l->reasm_buf;
1437 l->reasm_buf = NULL;
1438 }
1439}
1440
1441/* tipc_link_proto_rcv(): receive link level protocol message :
1442 * Note that network plane id propagates through the network, and may
1443 * change at any time. The node with lowest numerical id determines
1444 * network plane
1445 */
1446static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
1447 struct sk_buff_head *xmitq)
1448{
1449 struct tipc_msg *hdr = buf_msg(skb);
1450 u16 rcvgap = 0;
1451 u16 ack = msg_ack(hdr);
1452 u16 gap = msg_seq_gap(hdr);
1453 u16 peers_snd_nxt = msg_next_sent(hdr);
1454 u16 peers_tol = msg_link_tolerance(hdr);
1455 u16 peers_prio = msg_linkprio(hdr);
1456 u16 rcv_nxt = l->rcv_nxt;
1457 u16 dlen = msg_data_sz(hdr);
1458 int mtyp = msg_type(hdr);
1459 bool reply = msg_probe(hdr);
1460 void *data;
1461 char *if_name;
1462 int rc = 0;
1463
1464 if (tipc_link_is_blocked(l) || !xmitq)
1465 goto exit;
1466
1467 if (tipc_own_addr(l->net) > msg_prevnode(hdr))
1468 l->net_plane = msg_net_plane(hdr);
1469
1470 skb_linearize(skb);
1471 hdr = buf_msg(skb);
1472 data = msg_data(hdr);
1473
1474 switch (mtyp) {
1475 case RESET_MSG:
1476
1477 /* Ignore duplicate RESET with old session number */
1478 if ((less_eq(msg_session(hdr), l->peer_session)) &&
1479 (l->peer_session != ANY_SESSION))
1480 break;
1481 /* fall thru' */
1482
1483 case ACTIVATE_MSG:
1484
1485 /* Complete own link name with peer's interface name */
1486 if_name = strrchr(l->name, ':') + 1;
1487 if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME)
1488 break;
1489 if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME)
1490 break;
1491 strncpy(if_name, data, TIPC_MAX_IF_NAME);
1492
1493 /* Update own tolerance if peer indicates a non-zero value */
1494 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL))
1495 l->tolerance = peers_tol;
1496
1497 /* Update own priority if peer's priority is higher */
1498 if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
1499 l->priority = peers_prio;
1500
1501 /* ACTIVATE_MSG serves as PEER_RESET if link is already down */
1502 if (msg_peer_stopping(hdr))
1503 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1504 else if ((mtyp == RESET_MSG) || !link_is_up(l))
1505 rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT);
1506
1507 /* ACTIVATE_MSG takes up link if it was already locally reset */
1508 if ((mtyp == ACTIVATE_MSG) && (l->state == LINK_ESTABLISHING))
1509 rc = TIPC_LINK_UP_EVT;
1510
1511 l->peer_session = msg_session(hdr);
1512 l->peer_bearer_id = msg_bearer_id(hdr);
1513 if (l->mtu > msg_max_pkt(hdr))
1514 l->mtu = msg_max_pkt(hdr);
1515 break;
1516
1517 case STATE_MSG:
1518
1519 /* Update own tolerance if peer indicates a non-zero value */
1520 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL))
1521 l->tolerance = peers_tol;
1522
1523 /* Update own prio if peer indicates a different value */
1524 if ((peers_prio != l->priority) &&
1525 in_range(peers_prio, 1, TIPC_MAX_LINK_PRI)) {
1526 l->priority = peers_prio;
1527 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1528 }
1529
1530 l->silent_intv_cnt = 0;
1531 l->stats.recv_states++;
1532 if (msg_probe(hdr))
1533 l->stats.recv_probes++;
1534
1535 if (!link_is_up(l)) {
1536 if (l->state == LINK_ESTABLISHING)
1537 rc = TIPC_LINK_UP_EVT;
1538 break;
1539 }
1540 tipc_mon_rcv(l->net, data, dlen, l->addr,
1541 &l->mon_state, l->bearer_id);
1542
1543 /* Send NACK if peer has sent pkts we haven't received yet */
1544 if (more(peers_snd_nxt, rcv_nxt) && !tipc_link_is_synching(l))
1545 rcvgap = peers_snd_nxt - l->rcv_nxt;
1546 if (rcvgap || reply)
1547 tipc_link_build_proto_msg(l, STATE_MSG, 0, reply,
1548 rcvgap, 0, 0, xmitq);
1549 tipc_link_release_pkts(l, ack);
1550
1551 /* If NACK, retransmit will now start at right position */
1552 if (gap) {
1553 rc = tipc_link_retrans(l, l, ack + 1, ack + gap, xmitq);
1554 l->stats.recv_nacks++;
1555 }
1556
1557 tipc_link_advance_backlog(l, xmitq);
1558 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1559 link_prepare_wakeup(l);
1560 }
1561exit:
1562 kfree_skb(skb);
1563 return rc;
1564}
1565
1566/* tipc_link_build_bc_proto_msg() - create broadcast protocol message
1567 */
1568static bool tipc_link_build_bc_proto_msg(struct tipc_link *l, bool bcast,
1569 u16 peers_snd_nxt,
1570 struct sk_buff_head *xmitq)
1571{
1572 struct sk_buff *skb;
1573 struct tipc_msg *hdr;
1574 struct sk_buff *dfrd_skb = skb_peek(&l->deferdq);
1575 u16 ack = l->rcv_nxt - 1;
1576 u16 gap_to = peers_snd_nxt - 1;
1577
1578 skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE,
1579 0, l->addr, tipc_own_addr(l->net), 0, 0, 0);
1580 if (!skb)
1581 return false;
1582 hdr = buf_msg(skb);
1583 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
1584 msg_set_bcast_ack(hdr, ack);
1585 msg_set_bcgap_after(hdr, ack);
1586 if (dfrd_skb)
1587 gap_to = buf_seqno(dfrd_skb) - 1;
1588 msg_set_bcgap_to(hdr, gap_to);
1589 msg_set_non_seq(hdr, bcast);
1590 __skb_queue_tail(xmitq, skb);
1591 return true;
1592}
1593
1594/* tipc_link_build_bc_init_msg() - synchronize broadcast link endpoints.
1595 *
1596 * Give a newly added peer node the sequence number where it should
1597 * start receiving and acking broadcast packets.
1598 */
1599static void tipc_link_build_bc_init_msg(struct tipc_link *l,
1600 struct sk_buff_head *xmitq)
1601{
1602 struct sk_buff_head list;
1603
1604 __skb_queue_head_init(&list);
1605 if (!tipc_link_build_bc_proto_msg(l->bc_rcvlink, false, 0, &list))
1606 return;
1607 msg_set_bc_ack_invalid(buf_msg(skb_peek(&list)), true);
1608 tipc_link_xmit(l, &list, xmitq);
1609}
1610
1611/* tipc_link_bc_init_rcv - receive initial broadcast synch data from peer
1612 */
1613void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr)
1614{
1615 int mtyp = msg_type(hdr);
1616 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
1617
1618 if (link_is_up(l))
1619 return;
1620
1621 if (msg_user(hdr) == BCAST_PROTOCOL) {
1622 l->rcv_nxt = peers_snd_nxt;
1623 l->state = LINK_ESTABLISHED;
1624 return;
1625 }
1626
1627 if (l->peer_caps & TIPC_BCAST_SYNCH)
1628 return;
1629
1630 if (msg_peer_node_is_up(hdr))
1631 return;
1632
1633 /* Compatibility: accept older, less safe initial synch data */
1634 if ((mtyp == RESET_MSG) || (mtyp == ACTIVATE_MSG))
1635 l->rcv_nxt = peers_snd_nxt;
1636}
1637
1638/* link_bc_retr eval()- check if the indicated range can be retransmitted now
1639 * - Adjust permitted range if there is overlap with previous retransmission
1640 */
1641static bool link_bc_retr_eval(struct tipc_link *l, u16 *from, u16 *to)
1642{
1643 unsigned long elapsed = jiffies_to_msecs(jiffies - l->prev_retr);
1644
1645 if (less(*to, *from))
1646 return false;
1647
1648 /* New retransmission request */
1649 if ((elapsed > TIPC_BC_RETR_LIMIT) ||
1650 less(*to, l->prev_from) || more(*from, l->prev_to)) {
1651 l->prev_from = *from;
1652 l->prev_to = *to;
1653 l->prev_retr = jiffies;
1654 return true;
1655 }
1656
1657 /* Inside range of previous retransmit */
1658 if (!less(*from, l->prev_from) && !more(*to, l->prev_to))
1659 return false;
1660
1661 /* Fully or partially outside previous range => exclude overlap */
1662 if (less(*from, l->prev_from)) {
1663 *to = l->prev_from - 1;
1664 l->prev_from = *from;
1665 }
1666 if (more(*to, l->prev_to)) {
1667 *from = l->prev_to + 1;
1668 l->prev_to = *to;
1669 }
1670 l->prev_retr = jiffies;
1671 return true;
1672}
1673
1674/* tipc_link_bc_sync_rcv - update rcv link according to peer's send state
1675 */
1676int tipc_link_bc_sync_rcv(struct tipc_link *l, struct tipc_msg *hdr,
1677 struct sk_buff_head *xmitq)
1678{
1679 struct tipc_link *snd_l = l->bc_sndlink;
1680 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
1681 u16 from = msg_bcast_ack(hdr) + 1;
1682 u16 to = from + msg_bc_gap(hdr) - 1;
1683 int rc = 0;
1684
1685 if (!link_is_up(l))
1686 return rc;
1687
1688 if (!msg_peer_node_is_up(hdr))
1689 return rc;
1690
1691 /* Open when peer ackowledges our bcast init msg (pkt #1) */
1692 if (msg_ack(hdr))
1693 l->bc_peer_is_up = true;
1694
1695 if (!l->bc_peer_is_up)
1696 return rc;
1697
1698 l->stats.recv_nacks++;
1699
1700 /* Ignore if peers_snd_nxt goes beyond receive window */
1701 if (more(peers_snd_nxt, l->rcv_nxt + l->window))
1702 return rc;
1703
1704 if (link_bc_retr_eval(snd_l, &from, &to))
1705 rc = tipc_link_retrans(snd_l, l, from, to, xmitq);
1706
1707 l->snd_nxt = peers_snd_nxt;
1708 if (link_bc_rcv_gap(l))
1709 rc |= TIPC_LINK_SND_STATE;
1710
1711 /* Return now if sender supports nack via STATE messages */
1712 if (l->peer_caps & TIPC_BCAST_STATE_NACK)
1713 return rc;
1714
1715 /* Otherwise, be backwards compatible */
1716
1717 if (!more(peers_snd_nxt, l->rcv_nxt)) {
1718 l->nack_state = BC_NACK_SND_CONDITIONAL;
1719 return 0;
1720 }
1721
1722 /* Don't NACK if one was recently sent or peeked */
1723 if (l->nack_state == BC_NACK_SND_SUPPRESS) {
1724 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
1725 return 0;
1726 }
1727
1728 /* Conditionally delay NACK sending until next synch rcv */
1729 if (l->nack_state == BC_NACK_SND_CONDITIONAL) {
1730 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
1731 if ((peers_snd_nxt - l->rcv_nxt) < TIPC_MIN_LINK_WIN)
1732 return 0;
1733 }
1734
1735 /* Send NACK now but suppress next one */
1736 tipc_link_build_bc_proto_msg(l, true, peers_snd_nxt, xmitq);
1737 l->nack_state = BC_NACK_SND_SUPPRESS;
1738 return 0;
1739}
1740
1741void tipc_link_bc_ack_rcv(struct tipc_link *l, u16 acked,
1742 struct sk_buff_head *xmitq)
1743{
1744 struct sk_buff *skb, *tmp;
1745 struct tipc_link *snd_l = l->bc_sndlink;
1746
1747 if (!link_is_up(l) || !l->bc_peer_is_up)
1748 return;
1749
1750 if (!more(acked, l->acked))
1751 return;
1752
1753 /* Skip over packets peer has already acked */
1754 skb_queue_walk(&snd_l->transmq, skb) {
1755 if (more(buf_seqno(skb), l->acked))
1756 break;
1757 }
1758
1759 /* Update/release the packets peer is acking now */
1760 skb_queue_walk_from_safe(&snd_l->transmq, skb, tmp) {
1761 if (more(buf_seqno(skb), acked))
1762 break;
1763 if (!--TIPC_SKB_CB(skb)->ackers) {
1764 __skb_unlink(skb, &snd_l->transmq);
1765 kfree_skb(skb);
1766 }
1767 }
1768 l->acked = acked;
1769 tipc_link_advance_backlog(snd_l, xmitq);
1770 if (unlikely(!skb_queue_empty(&snd_l->wakeupq)))
1771 link_prepare_wakeup(snd_l);
1772}
1773
1774/* tipc_link_bc_nack_rcv(): receive broadcast nack message
1775 * This function is here for backwards compatibility, since
1776 * no BCAST_PROTOCOL/STATE messages occur from TIPC v2.5.
1777 */
1778int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb,
1779 struct sk_buff_head *xmitq)
1780{
1781 struct tipc_msg *hdr = buf_msg(skb);
1782 u32 dnode = msg_destnode(hdr);
1783 int mtyp = msg_type(hdr);
1784 u16 acked = msg_bcast_ack(hdr);
1785 u16 from = acked + 1;
1786 u16 to = msg_bcgap_to(hdr);
1787 u16 peers_snd_nxt = to + 1;
1788 int rc = 0;
1789
1790 kfree_skb(skb);
1791
1792 if (!tipc_link_is_up(l) || !l->bc_peer_is_up)
1793 return 0;
1794
1795 if (mtyp != STATE_MSG)
1796 return 0;
1797
1798 if (dnode == tipc_own_addr(l->net)) {
1799 tipc_link_bc_ack_rcv(l, acked, xmitq);
1800 rc = tipc_link_retrans(l->bc_sndlink, l, from, to, xmitq);
1801 l->stats.recv_nacks++;
1802 return rc;
1803 }
1804
1805 /* Msg for other node => suppress own NACK at next sync if applicable */
1806 if (more(peers_snd_nxt, l->rcv_nxt) && !less(l->rcv_nxt, from))
1807 l->nack_state = BC_NACK_SND_SUPPRESS;
1808
1809 return 0;
1810}
1811
1812void tipc_link_set_queue_limits(struct tipc_link *l, u32 win)
1813{
1814 int max_bulk = TIPC_MAX_PUBL / (l->mtu / ITEM_SIZE);
1815
1816 l->window = win;
1817 l->backlog[TIPC_LOW_IMPORTANCE].limit = max_t(u16, 50, win);
1818 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = max_t(u16, 100, win * 2);
1819 l->backlog[TIPC_HIGH_IMPORTANCE].limit = max_t(u16, 150, win * 3);
1820 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = max_t(u16, 200, win * 4);
1821 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk;
1822}
1823
1824/**
1825 * link_reset_stats - reset link statistics
1826 * @l: pointer to link
1827 */
1828void tipc_link_reset_stats(struct tipc_link *l)
1829{
1830 memset(&l->stats, 0, sizeof(l->stats));
1831}
1832
1833static void link_print(struct tipc_link *l, const char *str)
1834{
1835 struct sk_buff *hskb = skb_peek(&l->transmq);
1836 u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1;
1837 u16 tail = l->snd_nxt - 1;
1838
1839 pr_info("%s Link <%s> state %x\n", str, l->name, l->state);
1840 pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n",
1841 skb_queue_len(&l->transmq), head, tail,
1842 skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt);
1843}
1844
1845/* Parse and validate nested (link) properties valid for media, bearer and link
1846 */
1847int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
1848{
1849 int err;
1850
1851 err = nla_parse_nested(props, TIPC_NLA_PROP_MAX, prop,
1852 tipc_nl_prop_policy, NULL);
1853 if (err)
1854 return err;
1855
1856 if (props[TIPC_NLA_PROP_PRIO]) {
1857 u32 prio;
1858
1859 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
1860 if (prio > TIPC_MAX_LINK_PRI)
1861 return -EINVAL;
1862 }
1863
1864 if (props[TIPC_NLA_PROP_TOL]) {
1865 u32 tol;
1866
1867 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
1868 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
1869 return -EINVAL;
1870 }
1871
1872 if (props[TIPC_NLA_PROP_WIN]) {
1873 u32 win;
1874
1875 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
1876 if ((win < TIPC_MIN_LINK_WIN) || (win > TIPC_MAX_LINK_WIN))
1877 return -EINVAL;
1878 }
1879
1880 return 0;
1881}
1882
1883static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
1884{
1885 int i;
1886 struct nlattr *stats;
1887
1888 struct nla_map {
1889 u32 key;
1890 u32 val;
1891 };
1892
1893 struct nla_map map[] = {
1894 {TIPC_NLA_STATS_RX_INFO, 0},
1895 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
1896 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
1897 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
1898 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
1899 {TIPC_NLA_STATS_TX_INFO, 0},
1900 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
1901 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
1902 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
1903 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
1904 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
1905 s->msg_length_counts : 1},
1906 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
1907 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
1908 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
1909 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
1910 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
1911 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
1912 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
1913 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
1914 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
1915 {TIPC_NLA_STATS_RX_STATES, s->recv_states},
1916 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
1917 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
1918 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
1919 {TIPC_NLA_STATS_TX_STATES, s->sent_states},
1920 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
1921 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
1922 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
1923 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
1924 {TIPC_NLA_STATS_DUPLICATES, s->duplicates},
1925 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
1926 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
1927 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
1928 (s->accu_queue_sz / s->queue_sz_counts) : 0}
1929 };
1930
1931 stats = nla_nest_start(skb, TIPC_NLA_LINK_STATS);
1932 if (!stats)
1933 return -EMSGSIZE;
1934
1935 for (i = 0; i < ARRAY_SIZE(map); i++)
1936 if (nla_put_u32(skb, map[i].key, map[i].val))
1937 goto msg_full;
1938
1939 nla_nest_end(skb, stats);
1940
1941 return 0;
1942msg_full:
1943 nla_nest_cancel(skb, stats);
1944
1945 return -EMSGSIZE;
1946}
1947
1948/* Caller should hold appropriate locks to protect the link */
1949int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
1950 struct tipc_link *link, int nlflags)
1951{
1952 u32 self = tipc_own_addr(net);
1953 struct nlattr *attrs;
1954 struct nlattr *prop;
1955 void *hdr;
1956 int err;
1957
1958 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
1959 nlflags, TIPC_NL_LINK_GET);
1960 if (!hdr)
1961 return -EMSGSIZE;
1962
1963 attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK);
1964 if (!attrs)
1965 goto msg_full;
1966
1967 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
1968 goto attr_msg_full;
1969 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST, tipc_cluster_mask(self)))
1970 goto attr_msg_full;
1971 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu))
1972 goto attr_msg_full;
1973 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->stats.recv_pkts))
1974 goto attr_msg_full;
1975 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->stats.sent_pkts))
1976 goto attr_msg_full;
1977
1978 if (tipc_link_is_up(link))
1979 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
1980 goto attr_msg_full;
1981 if (link->active)
1982 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
1983 goto attr_msg_full;
1984
1985 prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP);
1986 if (!prop)
1987 goto attr_msg_full;
1988 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
1989 goto prop_msg_full;
1990 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
1991 goto prop_msg_full;
1992 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
1993 link->window))
1994 goto prop_msg_full;
1995 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
1996 goto prop_msg_full;
1997 nla_nest_end(msg->skb, prop);
1998
1999 err = __tipc_nl_add_stats(msg->skb, &link->stats);
2000 if (err)
2001 goto attr_msg_full;
2002
2003 nla_nest_end(msg->skb, attrs);
2004 genlmsg_end(msg->skb, hdr);
2005
2006 return 0;
2007
2008prop_msg_full:
2009 nla_nest_cancel(msg->skb, prop);
2010attr_msg_full:
2011 nla_nest_cancel(msg->skb, attrs);
2012msg_full:
2013 genlmsg_cancel(msg->skb, hdr);
2014
2015 return -EMSGSIZE;
2016}
2017
2018static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb,
2019 struct tipc_stats *stats)
2020{
2021 int i;
2022 struct nlattr *nest;
2023
2024 struct nla_map {
2025 __u32 key;
2026 __u32 val;
2027 };
2028
2029 struct nla_map map[] = {
2030 {TIPC_NLA_STATS_RX_INFO, stats->recv_pkts},
2031 {TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments},
2032 {TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented},
2033 {TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles},
2034 {TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled},
2035 {TIPC_NLA_STATS_TX_INFO, stats->sent_pkts},
2036 {TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments},
2037 {TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented},
2038 {TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles},
2039 {TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled},
2040 {TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks},
2041 {TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv},
2042 {TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks},
2043 {TIPC_NLA_STATS_TX_ACKS, stats->sent_acks},
2044 {TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted},
2045 {TIPC_NLA_STATS_DUPLICATES, stats->duplicates},
2046 {TIPC_NLA_STATS_LINK_CONGS, stats->link_congs},
2047 {TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz},
2048 {TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ?
2049 (stats->accu_queue_sz / stats->queue_sz_counts) : 0}
2050 };
2051
2052 nest = nla_nest_start(skb, TIPC_NLA_LINK_STATS);
2053 if (!nest)
2054 return -EMSGSIZE;
2055
2056 for (i = 0; i < ARRAY_SIZE(map); i++)
2057 if (nla_put_u32(skb, map[i].key, map[i].val))
2058 goto msg_full;
2059
2060 nla_nest_end(skb, nest);
2061
2062 return 0;
2063msg_full:
2064 nla_nest_cancel(skb, nest);
2065
2066 return -EMSGSIZE;
2067}
2068
2069int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg)
2070{
2071 int err;
2072 void *hdr;
2073 struct nlattr *attrs;
2074 struct nlattr *prop;
2075 struct tipc_net *tn = net_generic(net, tipc_net_id);
2076 struct tipc_link *bcl = tn->bcl;
2077
2078 if (!bcl)
2079 return 0;
2080
2081 tipc_bcast_lock(net);
2082
2083 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2084 NLM_F_MULTI, TIPC_NL_LINK_GET);
2085 if (!hdr) {
2086 tipc_bcast_unlock(net);
2087 return -EMSGSIZE;
2088 }
2089
2090 attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK);
2091 if (!attrs)
2092 goto msg_full;
2093
2094 /* The broadcast link is always up */
2095 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2096 goto attr_msg_full;
2097
2098 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST))
2099 goto attr_msg_full;
2100 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name))
2101 goto attr_msg_full;
2102 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, 0))
2103 goto attr_msg_full;
2104 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, 0))
2105 goto attr_msg_full;
2106
2107 prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP);
2108 if (!prop)
2109 goto attr_msg_full;
2110 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->window))
2111 goto prop_msg_full;
2112 nla_nest_end(msg->skb, prop);
2113
2114 err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats);
2115 if (err)
2116 goto attr_msg_full;
2117
2118 tipc_bcast_unlock(net);
2119 nla_nest_end(msg->skb, attrs);
2120 genlmsg_end(msg->skb, hdr);
2121
2122 return 0;
2123
2124prop_msg_full:
2125 nla_nest_cancel(msg->skb, prop);
2126attr_msg_full:
2127 nla_nest_cancel(msg->skb, attrs);
2128msg_full:
2129 tipc_bcast_unlock(net);
2130 genlmsg_cancel(msg->skb, hdr);
2131
2132 return -EMSGSIZE;
2133}
2134
2135void tipc_link_set_tolerance(struct tipc_link *l, u32 tol,
2136 struct sk_buff_head *xmitq)
2137{
2138 l->tolerance = tol;
2139 if (link_is_up(l))
2140 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, tol, 0, xmitq);
2141}
2142
2143void tipc_link_set_prio(struct tipc_link *l, u32 prio,
2144 struct sk_buff_head *xmitq)
2145{
2146 l->priority = prio;
2147 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, prio, xmitq);
2148}
2149
2150void tipc_link_set_abort_limit(struct tipc_link *l, u32 limit)
2151{
2152 l->abort_limit = limit;
2153}