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 tipc_link_name - deconstructed link name
75 * @addr_local: network address of node at this end
76 * @if_local: name of interface at this end
77 * @addr_peer: network address of node at far end
78 * @if_peer: name of interface at far end
79 */
80
81 struct tipc_link_name {
82 u32 addr_local;
83 char if_local[TIPC_MAX_IF_NAME];
84 u32 addr_peer;
85 char if_peer[TIPC_MAX_IF_NAME];
86 };
87
88 static void link_handle_out_of_seq_msg(struct tipc_link *l_ptr,
89 struct sk_buff *buf);
90 static void link_recv_proto_msg(struct tipc_link *l_ptr, struct sk_buff *buf);
91 static int link_recv_changeover_msg(struct tipc_link **l_ptr,
92 struct sk_buff **buf);
93 static void link_set_supervision_props(struct tipc_link *l_ptr, u32 tolerance);
94 static int link_send_sections_long(struct tipc_port *sender,
95 struct iovec const *msg_sect,
96 u32 num_sect, unsigned int total_len,
97 u32 destnode);
98 static void link_check_defragm_bufs(struct tipc_link *l_ptr);
99 static void link_state_event(struct tipc_link *l_ptr, u32 event);
100 static void link_reset_statistics(struct tipc_link *l_ptr);
101 static void link_print(struct tipc_link *l_ptr, const char *str);
102 static void link_start(struct tipc_link *l_ptr);
103 static int link_send_long_buf(struct tipc_link *l_ptr, struct sk_buff *buf);
104
105 /*
106 * Simple link routines
107 */
108
align(unsigned int i)109 static unsigned int align(unsigned int i)
110 {
111 return (i + 3) & ~3u;
112 }
113
link_init_max_pkt(struct tipc_link * l_ptr)114 static void link_init_max_pkt(struct tipc_link *l_ptr)
115 {
116 u32 max_pkt;
117
118 max_pkt = (l_ptr->b_ptr->mtu & ~3);
119 if (max_pkt > MAX_MSG_SIZE)
120 max_pkt = MAX_MSG_SIZE;
121
122 l_ptr->max_pkt_target = max_pkt;
123 if (l_ptr->max_pkt_target < MAX_PKT_DEFAULT)
124 l_ptr->max_pkt = l_ptr->max_pkt_target;
125 else
126 l_ptr->max_pkt = MAX_PKT_DEFAULT;
127
128 l_ptr->max_pkt_probes = 0;
129 }
130
link_next_sent(struct tipc_link * l_ptr)131 static u32 link_next_sent(struct tipc_link *l_ptr)
132 {
133 if (l_ptr->next_out)
134 return buf_seqno(l_ptr->next_out);
135 return mod(l_ptr->next_out_no);
136 }
137
link_last_sent(struct tipc_link * l_ptr)138 static u32 link_last_sent(struct tipc_link *l_ptr)
139 {
140 return mod(link_next_sent(l_ptr) - 1);
141 }
142
143 /*
144 * Simple non-static link routines (i.e. referenced outside this file)
145 */
146
tipc_link_is_up(struct tipc_link * l_ptr)147 int tipc_link_is_up(struct tipc_link *l_ptr)
148 {
149 if (!l_ptr)
150 return 0;
151 return link_working_working(l_ptr) || link_working_unknown(l_ptr);
152 }
153
tipc_link_is_active(struct tipc_link * l_ptr)154 int tipc_link_is_active(struct tipc_link *l_ptr)
155 {
156 return (l_ptr->owner->active_links[0] == l_ptr) ||
157 (l_ptr->owner->active_links[1] == l_ptr);
158 }
159
160 /**
161 * link_name_validate - validate & (optionally) deconstruct tipc_link name
162 * @name - ptr to link name string
163 * @name_parts - ptr to area for link name components (or NULL if not needed)
164 *
165 * Returns 1 if link name is valid, otherwise 0.
166 */
167
link_name_validate(const char * name,struct tipc_link_name * name_parts)168 static int link_name_validate(const char *name,
169 struct tipc_link_name *name_parts)
170 {
171 char name_copy[TIPC_MAX_LINK_NAME];
172 char *addr_local;
173 char *if_local;
174 char *addr_peer;
175 char *if_peer;
176 char dummy;
177 u32 z_local, c_local, n_local;
178 u32 z_peer, c_peer, n_peer;
179 u32 if_local_len;
180 u32 if_peer_len;
181
182 /* copy link name & ensure length is OK */
183
184 name_copy[TIPC_MAX_LINK_NAME - 1] = 0;
185 /* need above in case non-Posix strncpy() doesn't pad with nulls */
186 strncpy(name_copy, name, TIPC_MAX_LINK_NAME);
187 if (name_copy[TIPC_MAX_LINK_NAME - 1] != 0)
188 return 0;
189
190 /* ensure all component parts of link name are present */
191
192 addr_local = name_copy;
193 if_local = strchr(addr_local, ':');
194 if (if_local == NULL)
195 return 0;
196 *(if_local++) = 0;
197 addr_peer = strchr(if_local, '-');
198 if (addr_peer == NULL)
199 return 0;
200 *(addr_peer++) = 0;
201 if_local_len = addr_peer - if_local;
202 if_peer = strchr(addr_peer, ':');
203 if (if_peer == NULL)
204 return 0;
205 *(if_peer++) = 0;
206 if_peer_len = strlen(if_peer) + 1;
207
208 /* validate component parts of link name */
209
210 if ((sscanf(addr_local, "%u.%u.%u%c",
211 &z_local, &c_local, &n_local, &dummy) != 3) ||
212 (sscanf(addr_peer, "%u.%u.%u%c",
213 &z_peer, &c_peer, &n_peer, &dummy) != 3) ||
214 (z_local > 255) || (c_local > 4095) || (n_local > 4095) ||
215 (z_peer > 255) || (c_peer > 4095) || (n_peer > 4095) ||
216 (if_local_len <= 1) || (if_local_len > TIPC_MAX_IF_NAME) ||
217 (if_peer_len <= 1) || (if_peer_len > TIPC_MAX_IF_NAME) ||
218 (strspn(if_local, tipc_alphabet) != (if_local_len - 1)) ||
219 (strspn(if_peer, tipc_alphabet) != (if_peer_len - 1)))
220 return 0;
221
222 /* return link name components, if necessary */
223
224 if (name_parts) {
225 name_parts->addr_local = tipc_addr(z_local, c_local, n_local);
226 strcpy(name_parts->if_local, if_local);
227 name_parts->addr_peer = tipc_addr(z_peer, c_peer, n_peer);
228 strcpy(name_parts->if_peer, if_peer);
229 }
230 return 1;
231 }
232
233 /**
234 * link_timeout - handle expiration of link timer
235 * @l_ptr: pointer to link
236 *
237 * This routine must not grab "tipc_net_lock" to avoid a potential deadlock conflict
238 * with tipc_link_delete(). (There is no risk that the node will be deleted by
239 * another thread because tipc_link_delete() always cancels the link timer before
240 * tipc_node_delete() is called.)
241 */
242
link_timeout(struct tipc_link * l_ptr)243 static void link_timeout(struct tipc_link *l_ptr)
244 {
245 tipc_node_lock(l_ptr->owner);
246
247 /* update counters used in statistical profiling of send traffic */
248
249 l_ptr->stats.accu_queue_sz += l_ptr->out_queue_size;
250 l_ptr->stats.queue_sz_counts++;
251
252 if (l_ptr->first_out) {
253 struct tipc_msg *msg = buf_msg(l_ptr->first_out);
254 u32 length = msg_size(msg);
255
256 if ((msg_user(msg) == MSG_FRAGMENTER) &&
257 (msg_type(msg) == FIRST_FRAGMENT)) {
258 length = msg_size(msg_get_wrapped(msg));
259 }
260 if (length) {
261 l_ptr->stats.msg_lengths_total += length;
262 l_ptr->stats.msg_length_counts++;
263 if (length <= 64)
264 l_ptr->stats.msg_length_profile[0]++;
265 else if (length <= 256)
266 l_ptr->stats.msg_length_profile[1]++;
267 else if (length <= 1024)
268 l_ptr->stats.msg_length_profile[2]++;
269 else if (length <= 4096)
270 l_ptr->stats.msg_length_profile[3]++;
271 else if (length <= 16384)
272 l_ptr->stats.msg_length_profile[4]++;
273 else if (length <= 32768)
274 l_ptr->stats.msg_length_profile[5]++;
275 else
276 l_ptr->stats.msg_length_profile[6]++;
277 }
278 }
279
280 /* do all other link processing performed on a periodic basis */
281
282 link_check_defragm_bufs(l_ptr);
283
284 link_state_event(l_ptr, TIMEOUT_EVT);
285
286 if (l_ptr->next_out)
287 tipc_link_push_queue(l_ptr);
288
289 tipc_node_unlock(l_ptr->owner);
290 }
291
link_set_timer(struct tipc_link * l_ptr,u32 time)292 static void link_set_timer(struct tipc_link *l_ptr, u32 time)
293 {
294 k_start_timer(&l_ptr->timer, time);
295 }
296
297 /**
298 * tipc_link_create - create a new link
299 * @n_ptr: pointer to associated node
300 * @b_ptr: pointer to associated bearer
301 * @media_addr: media address to use when sending messages over link
302 *
303 * Returns pointer to link.
304 */
305
tipc_link_create(struct tipc_node * n_ptr,struct tipc_bearer * b_ptr,const struct tipc_media_addr * media_addr)306 struct tipc_link *tipc_link_create(struct tipc_node *n_ptr,
307 struct tipc_bearer *b_ptr,
308 const struct tipc_media_addr *media_addr)
309 {
310 struct tipc_link *l_ptr;
311 struct tipc_msg *msg;
312 char *if_name;
313 char addr_string[16];
314 u32 peer = n_ptr->addr;
315
316 if (n_ptr->link_cnt >= 2) {
317 tipc_addr_string_fill(addr_string, n_ptr->addr);
318 err("Attempt to establish third link to %s\n", addr_string);
319 return NULL;
320 }
321
322 if (n_ptr->links[b_ptr->identity]) {
323 tipc_addr_string_fill(addr_string, n_ptr->addr);
324 err("Attempt to establish second link on <%s> to %s\n",
325 b_ptr->name, addr_string);
326 return NULL;
327 }
328
329 l_ptr = kzalloc(sizeof(*l_ptr), GFP_ATOMIC);
330 if (!l_ptr) {
331 warn("Link creation failed, no memory\n");
332 return NULL;
333 }
334
335 l_ptr->addr = peer;
336 if_name = strchr(b_ptr->name, ':') + 1;
337 sprintf(l_ptr->name, "%u.%u.%u:%s-%u.%u.%u:unknown",
338 tipc_zone(tipc_own_addr), tipc_cluster(tipc_own_addr),
339 tipc_node(tipc_own_addr),
340 if_name,
341 tipc_zone(peer), tipc_cluster(peer), tipc_node(peer));
342 /* note: peer i/f name is updated by reset/activate message */
343 memcpy(&l_ptr->media_addr, media_addr, sizeof(*media_addr));
344 l_ptr->owner = n_ptr;
345 l_ptr->checkpoint = 1;
346 l_ptr->peer_session = INVALID_SESSION;
347 l_ptr->b_ptr = b_ptr;
348 link_set_supervision_props(l_ptr, b_ptr->tolerance);
349 l_ptr->state = RESET_UNKNOWN;
350
351 l_ptr->pmsg = (struct tipc_msg *)&l_ptr->proto_msg;
352 msg = l_ptr->pmsg;
353 tipc_msg_init(msg, LINK_PROTOCOL, RESET_MSG, INT_H_SIZE, l_ptr->addr);
354 msg_set_size(msg, sizeof(l_ptr->proto_msg));
355 msg_set_session(msg, (tipc_random & 0xffff));
356 msg_set_bearer_id(msg, b_ptr->identity);
357 strcpy((char *)msg_data(msg), if_name);
358
359 l_ptr->priority = b_ptr->priority;
360 tipc_link_set_queue_limits(l_ptr, b_ptr->window);
361
362 link_init_max_pkt(l_ptr);
363
364 l_ptr->next_out_no = 1;
365 INIT_LIST_HEAD(&l_ptr->waiting_ports);
366
367 link_reset_statistics(l_ptr);
368
369 tipc_node_attach_link(n_ptr, l_ptr);
370
371 k_init_timer(&l_ptr->timer, (Handler)link_timeout, (unsigned long)l_ptr);
372 list_add_tail(&l_ptr->link_list, &b_ptr->links);
373 tipc_k_signal((Handler)link_start, (unsigned long)l_ptr);
374
375 return l_ptr;
376 }
377
378 /**
379 * tipc_link_delete - delete a link
380 * @l_ptr: pointer to link
381 *
382 * Note: 'tipc_net_lock' is write_locked, bearer is locked.
383 * This routine must not grab the node lock until after link timer cancellation
384 * to avoid a potential deadlock situation.
385 */
386
tipc_link_delete(struct tipc_link * l_ptr)387 void tipc_link_delete(struct tipc_link *l_ptr)
388 {
389 if (!l_ptr) {
390 err("Attempt to delete non-existent link\n");
391 return;
392 }
393
394 k_cancel_timer(&l_ptr->timer);
395
396 tipc_node_lock(l_ptr->owner);
397 tipc_link_reset(l_ptr);
398 tipc_node_detach_link(l_ptr->owner, l_ptr);
399 tipc_link_stop(l_ptr);
400 list_del_init(&l_ptr->link_list);
401 tipc_node_unlock(l_ptr->owner);
402 k_term_timer(&l_ptr->timer);
403 kfree(l_ptr);
404 }
405
link_start(struct tipc_link * l_ptr)406 static void link_start(struct tipc_link *l_ptr)
407 {
408 tipc_node_lock(l_ptr->owner);
409 link_state_event(l_ptr, STARTING_EVT);
410 tipc_node_unlock(l_ptr->owner);
411 }
412
413 /**
414 * link_schedule_port - schedule port for deferred sending
415 * @l_ptr: pointer to link
416 * @origport: reference to sending port
417 * @sz: amount of data to be sent
418 *
419 * Schedules port for renewed sending of messages after link congestion
420 * has abated.
421 */
422
link_schedule_port(struct tipc_link * l_ptr,u32 origport,u32 sz)423 static int link_schedule_port(struct tipc_link *l_ptr, u32 origport, u32 sz)
424 {
425 struct tipc_port *p_ptr;
426
427 spin_lock_bh(&tipc_port_list_lock);
428 p_ptr = tipc_port_lock(origport);
429 if (p_ptr) {
430 if (!p_ptr->wakeup)
431 goto exit;
432 if (!list_empty(&p_ptr->wait_list))
433 goto exit;
434 p_ptr->congested = 1;
435 p_ptr->waiting_pkts = 1 + ((sz - 1) / l_ptr->max_pkt);
436 list_add_tail(&p_ptr->wait_list, &l_ptr->waiting_ports);
437 l_ptr->stats.link_congs++;
438 exit:
439 tipc_port_unlock(p_ptr);
440 }
441 spin_unlock_bh(&tipc_port_list_lock);
442 return -ELINKCONG;
443 }
444
tipc_link_wakeup_ports(struct tipc_link * l_ptr,int all)445 void tipc_link_wakeup_ports(struct tipc_link *l_ptr, int all)
446 {
447 struct tipc_port *p_ptr;
448 struct tipc_port *temp_p_ptr;
449 int win = l_ptr->queue_limit[0] - l_ptr->out_queue_size;
450
451 if (all)
452 win = 100000;
453 if (win <= 0)
454 return;
455 if (!spin_trylock_bh(&tipc_port_list_lock))
456 return;
457 if (link_congested(l_ptr))
458 goto exit;
459 list_for_each_entry_safe(p_ptr, temp_p_ptr, &l_ptr->waiting_ports,
460 wait_list) {
461 if (win <= 0)
462 break;
463 list_del_init(&p_ptr->wait_list);
464 spin_lock_bh(p_ptr->lock);
465 p_ptr->congested = 0;
466 p_ptr->wakeup(p_ptr);
467 win -= p_ptr->waiting_pkts;
468 spin_unlock_bh(p_ptr->lock);
469 }
470
471 exit:
472 spin_unlock_bh(&tipc_port_list_lock);
473 }
474
475 /**
476 * link_release_outqueue - purge link's outbound message queue
477 * @l_ptr: pointer to link
478 */
479
link_release_outqueue(struct tipc_link * l_ptr)480 static void link_release_outqueue(struct tipc_link *l_ptr)
481 {
482 struct sk_buff *buf = l_ptr->first_out;
483 struct sk_buff *next;
484
485 while (buf) {
486 next = buf->next;
487 kfree_skb(buf);
488 buf = next;
489 }
490 l_ptr->first_out = NULL;
491 l_ptr->out_queue_size = 0;
492 }
493
494 /**
495 * tipc_link_reset_fragments - purge link's inbound message fragments queue
496 * @l_ptr: pointer to link
497 */
498
tipc_link_reset_fragments(struct tipc_link * l_ptr)499 void tipc_link_reset_fragments(struct tipc_link *l_ptr)
500 {
501 struct sk_buff *buf = l_ptr->defragm_buf;
502 struct sk_buff *next;
503
504 while (buf) {
505 next = buf->next;
506 kfree_skb(buf);
507 buf = next;
508 }
509 l_ptr->defragm_buf = NULL;
510 }
511
512 /**
513 * tipc_link_stop - purge all inbound and outbound messages associated with link
514 * @l_ptr: pointer to link
515 */
516
tipc_link_stop(struct tipc_link * l_ptr)517 void tipc_link_stop(struct tipc_link *l_ptr)
518 {
519 struct sk_buff *buf;
520 struct sk_buff *next;
521
522 buf = l_ptr->oldest_deferred_in;
523 while (buf) {
524 next = buf->next;
525 kfree_skb(buf);
526 buf = next;
527 }
528
529 buf = l_ptr->first_out;
530 while (buf) {
531 next = buf->next;
532 kfree_skb(buf);
533 buf = next;
534 }
535
536 tipc_link_reset_fragments(l_ptr);
537
538 kfree_skb(l_ptr->proto_msg_queue);
539 l_ptr->proto_msg_queue = NULL;
540 }
541
tipc_link_reset(struct tipc_link * l_ptr)542 void tipc_link_reset(struct tipc_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 kfree_skb(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 kfree_skb(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
601
link_activate(struct tipc_link * l_ptr)602 static void link_activate(struct tipc_link *l_ptr)
603 {
604 l_ptr->next_in_no = l_ptr->stats.recv_info = 1;
605 tipc_node_link_up(l_ptr->owner, l_ptr);
606 tipc_bearer_add_dest(l_ptr->b_ptr, l_ptr->addr);
607 }
608
609 /**
610 * link_state_event - link finite state machine
611 * @l_ptr: pointer to link
612 * @event: state machine event to process
613 */
614
link_state_event(struct tipc_link * l_ptr,unsigned event)615 static void link_state_event(struct tipc_link *l_ptr, unsigned event)
616 {
617 struct tipc_link *other;
618 u32 cont_intv = l_ptr->continuity_interval;
619
620 if (!l_ptr->started && (event != STARTING_EVT))
621 return; /* Not yet. */
622
623 if (link_blocked(l_ptr)) {
624 if (event == TIMEOUT_EVT)
625 link_set_timer(l_ptr, cont_intv);
626 return; /* Changeover going on */
627 }
628
629 switch (l_ptr->state) {
630 case WORKING_WORKING:
631 switch (event) {
632 case TRAFFIC_MSG_EVT:
633 case ACTIVATE_MSG:
634 break;
635 case TIMEOUT_EVT:
636 if (l_ptr->next_in_no != l_ptr->checkpoint) {
637 l_ptr->checkpoint = l_ptr->next_in_no;
638 if (tipc_bclink_acks_missing(l_ptr->owner)) {
639 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
640 0, 0, 0, 0, 0);
641 l_ptr->fsm_msg_cnt++;
642 } else if (l_ptr->max_pkt < l_ptr->max_pkt_target) {
643 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
644 1, 0, 0, 0, 0);
645 l_ptr->fsm_msg_cnt++;
646 }
647 link_set_timer(l_ptr, cont_intv);
648 break;
649 }
650 l_ptr->state = WORKING_UNKNOWN;
651 l_ptr->fsm_msg_cnt = 0;
652 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
653 l_ptr->fsm_msg_cnt++;
654 link_set_timer(l_ptr, cont_intv / 4);
655 break;
656 case RESET_MSG:
657 info("Resetting link <%s>, requested by peer\n",
658 l_ptr->name);
659 tipc_link_reset(l_ptr);
660 l_ptr->state = RESET_RESET;
661 l_ptr->fsm_msg_cnt = 0;
662 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0);
663 l_ptr->fsm_msg_cnt++;
664 link_set_timer(l_ptr, cont_intv);
665 break;
666 default:
667 err("Unknown link event %u in WW state\n", event);
668 }
669 break;
670 case WORKING_UNKNOWN:
671 switch (event) {
672 case TRAFFIC_MSG_EVT:
673 case ACTIVATE_MSG:
674 l_ptr->state = WORKING_WORKING;
675 l_ptr->fsm_msg_cnt = 0;
676 link_set_timer(l_ptr, cont_intv);
677 break;
678 case RESET_MSG:
679 info("Resetting link <%s>, requested by peer "
680 "while probing\n", l_ptr->name);
681 tipc_link_reset(l_ptr);
682 l_ptr->state = RESET_RESET;
683 l_ptr->fsm_msg_cnt = 0;
684 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0);
685 l_ptr->fsm_msg_cnt++;
686 link_set_timer(l_ptr, cont_intv);
687 break;
688 case TIMEOUT_EVT:
689 if (l_ptr->next_in_no != l_ptr->checkpoint) {
690 l_ptr->state = WORKING_WORKING;
691 l_ptr->fsm_msg_cnt = 0;
692 l_ptr->checkpoint = l_ptr->next_in_no;
693 if (tipc_bclink_acks_missing(l_ptr->owner)) {
694 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
695 0, 0, 0, 0, 0);
696 l_ptr->fsm_msg_cnt++;
697 }
698 link_set_timer(l_ptr, cont_intv);
699 } else if (l_ptr->fsm_msg_cnt < l_ptr->abort_limit) {
700 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
701 1, 0, 0, 0, 0);
702 l_ptr->fsm_msg_cnt++;
703 link_set_timer(l_ptr, cont_intv / 4);
704 } else { /* Link has failed */
705 warn("Resetting link <%s>, peer not responding\n",
706 l_ptr->name);
707 tipc_link_reset(l_ptr);
708 l_ptr->state = RESET_UNKNOWN;
709 l_ptr->fsm_msg_cnt = 0;
710 tipc_link_send_proto_msg(l_ptr, RESET_MSG,
711 0, 0, 0, 0, 0);
712 l_ptr->fsm_msg_cnt++;
713 link_set_timer(l_ptr, cont_intv);
714 }
715 break;
716 default:
717 err("Unknown link event %u in WU state\n", event);
718 }
719 break;
720 case RESET_UNKNOWN:
721 switch (event) {
722 case TRAFFIC_MSG_EVT:
723 break;
724 case ACTIVATE_MSG:
725 other = l_ptr->owner->active_links[0];
726 if (other && link_working_unknown(other))
727 break;
728 l_ptr->state = WORKING_WORKING;
729 l_ptr->fsm_msg_cnt = 0;
730 link_activate(l_ptr);
731 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
732 l_ptr->fsm_msg_cnt++;
733 link_set_timer(l_ptr, cont_intv);
734 break;
735 case RESET_MSG:
736 l_ptr->state = RESET_RESET;
737 l_ptr->fsm_msg_cnt = 0;
738 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 1, 0, 0, 0, 0);
739 l_ptr->fsm_msg_cnt++;
740 link_set_timer(l_ptr, cont_intv);
741 break;
742 case STARTING_EVT:
743 l_ptr->started = 1;
744 /* fall through */
745 case TIMEOUT_EVT:
746 tipc_link_send_proto_msg(l_ptr, RESET_MSG, 0, 0, 0, 0, 0);
747 l_ptr->fsm_msg_cnt++;
748 link_set_timer(l_ptr, cont_intv);
749 break;
750 default:
751 err("Unknown link event %u in RU state\n", event);
752 }
753 break;
754 case RESET_RESET:
755 switch (event) {
756 case TRAFFIC_MSG_EVT:
757 case ACTIVATE_MSG:
758 other = l_ptr->owner->active_links[0];
759 if (other && link_working_unknown(other))
760 break;
761 l_ptr->state = WORKING_WORKING;
762 l_ptr->fsm_msg_cnt = 0;
763 link_activate(l_ptr);
764 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
765 l_ptr->fsm_msg_cnt++;
766 link_set_timer(l_ptr, cont_intv);
767 break;
768 case RESET_MSG:
769 break;
770 case TIMEOUT_EVT:
771 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0);
772 l_ptr->fsm_msg_cnt++;
773 link_set_timer(l_ptr, cont_intv);
774 break;
775 default:
776 err("Unknown link event %u in RR state\n", event);
777 }
778 break;
779 default:
780 err("Unknown link state %u/%u\n", l_ptr->state, event);
781 }
782 }
783
784 /*
785 * link_bundle_buf(): Append contents of a buffer to
786 * the tail of an existing one.
787 */
788
link_bundle_buf(struct tipc_link * l_ptr,struct sk_buff * bundler,struct sk_buff * buf)789 static int link_bundle_buf(struct tipc_link *l_ptr,
790 struct sk_buff *bundler,
791 struct sk_buff *buf)
792 {
793 struct tipc_msg *bundler_msg = buf_msg(bundler);
794 struct tipc_msg *msg = buf_msg(buf);
795 u32 size = msg_size(msg);
796 u32 bundle_size = msg_size(bundler_msg);
797 u32 to_pos = align(bundle_size);
798 u32 pad = to_pos - bundle_size;
799
800 if (msg_user(bundler_msg) != MSG_BUNDLER)
801 return 0;
802 if (msg_type(bundler_msg) != OPEN_MSG)
803 return 0;
804 if (skb_tailroom(bundler) < (pad + size))
805 return 0;
806 if (l_ptr->max_pkt < (to_pos + size))
807 return 0;
808
809 skb_put(bundler, pad + size);
810 skb_copy_to_linear_data_offset(bundler, to_pos, buf->data, size);
811 msg_set_size(bundler_msg, to_pos + size);
812 msg_set_msgcnt(bundler_msg, msg_msgcnt(bundler_msg) + 1);
813 kfree_skb(buf);
814 l_ptr->stats.sent_bundled++;
815 return 1;
816 }
817
link_add_to_outqueue(struct tipc_link * l_ptr,struct sk_buff * buf,struct tipc_msg * msg)818 static void link_add_to_outqueue(struct tipc_link *l_ptr,
819 struct sk_buff *buf,
820 struct tipc_msg *msg)
821 {
822 u32 ack = mod(l_ptr->next_in_no - 1);
823 u32 seqno = mod(l_ptr->next_out_no++);
824
825 msg_set_word(msg, 2, ((ack << 16) | seqno));
826 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
827 buf->next = NULL;
828 if (l_ptr->first_out) {
829 l_ptr->last_out->next = buf;
830 l_ptr->last_out = buf;
831 } else
832 l_ptr->first_out = l_ptr->last_out = buf;
833
834 l_ptr->out_queue_size++;
835 if (l_ptr->out_queue_size > l_ptr->stats.max_queue_sz)
836 l_ptr->stats.max_queue_sz = l_ptr->out_queue_size;
837 }
838
link_add_chain_to_outqueue(struct tipc_link * l_ptr,struct sk_buff * buf_chain,u32 long_msgno)839 static void link_add_chain_to_outqueue(struct tipc_link *l_ptr,
840 struct sk_buff *buf_chain,
841 u32 long_msgno)
842 {
843 struct sk_buff *buf;
844 struct tipc_msg *msg;
845
846 if (!l_ptr->next_out)
847 l_ptr->next_out = buf_chain;
848 while (buf_chain) {
849 buf = buf_chain;
850 buf_chain = buf_chain->next;
851
852 msg = buf_msg(buf);
853 msg_set_long_msgno(msg, long_msgno);
854 link_add_to_outqueue(l_ptr, buf, msg);
855 }
856 }
857
858 /*
859 * tipc_link_send_buf() is the 'full path' for messages, called from
860 * inside TIPC when the 'fast path' in tipc_send_buf
861 * has failed, and from link_send()
862 */
863
tipc_link_send_buf(struct tipc_link * l_ptr,struct sk_buff * buf)864 int tipc_link_send_buf(struct tipc_link *l_ptr, struct sk_buff *buf)
865 {
866 struct tipc_msg *msg = buf_msg(buf);
867 u32 size = msg_size(msg);
868 u32 dsz = msg_data_sz(msg);
869 u32 queue_size = l_ptr->out_queue_size;
870 u32 imp = tipc_msg_tot_importance(msg);
871 u32 queue_limit = l_ptr->queue_limit[imp];
872 u32 max_packet = l_ptr->max_pkt;
873
874 /* Match msg importance against queue limits: */
875
876 if (unlikely(queue_size >= queue_limit)) {
877 if (imp <= TIPC_CRITICAL_IMPORTANCE) {
878 link_schedule_port(l_ptr, msg_origport(msg), size);
879 kfree_skb(buf);
880 return -ELINKCONG;
881 }
882 kfree_skb(buf);
883 if (imp > CONN_MANAGER) {
884 warn("Resetting link <%s>, send queue full", l_ptr->name);
885 tipc_link_reset(l_ptr);
886 }
887 return dsz;
888 }
889
890 /* Fragmentation needed ? */
891
892 if (size > max_packet)
893 return link_send_long_buf(l_ptr, buf);
894
895 /* Packet can be queued or sent: */
896
897 if (likely(!tipc_bearer_congested(l_ptr->b_ptr, l_ptr) &&
898 !link_congested(l_ptr))) {
899 link_add_to_outqueue(l_ptr, buf, msg);
900
901 if (likely(tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr))) {
902 l_ptr->unacked_window = 0;
903 } else {
904 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr);
905 l_ptr->stats.bearer_congs++;
906 l_ptr->next_out = buf;
907 }
908 return dsz;
909 }
910 /* Congestion: can message be bundled ?: */
911
912 if ((msg_user(msg) != CHANGEOVER_PROTOCOL) &&
913 (msg_user(msg) != MSG_FRAGMENTER)) {
914
915 /* Try adding message to an existing bundle */
916
917 if (l_ptr->next_out &&
918 link_bundle_buf(l_ptr, l_ptr->last_out, buf)) {
919 tipc_bearer_resolve_congestion(l_ptr->b_ptr, l_ptr);
920 return dsz;
921 }
922
923 /* Try creating a new bundle */
924
925 if (size <= max_packet * 2 / 3) {
926 struct sk_buff *bundler = tipc_buf_acquire(max_packet);
927 struct tipc_msg bundler_hdr;
928
929 if (bundler) {
930 tipc_msg_init(&bundler_hdr, MSG_BUNDLER, OPEN_MSG,
931 INT_H_SIZE, l_ptr->addr);
932 skb_copy_to_linear_data(bundler, &bundler_hdr,
933 INT_H_SIZE);
934 skb_trim(bundler, INT_H_SIZE);
935 link_bundle_buf(l_ptr, bundler, buf);
936 buf = bundler;
937 msg = buf_msg(buf);
938 l_ptr->stats.sent_bundles++;
939 }
940 }
941 }
942 if (!l_ptr->next_out)
943 l_ptr->next_out = buf;
944 link_add_to_outqueue(l_ptr, buf, msg);
945 tipc_bearer_resolve_congestion(l_ptr->b_ptr, l_ptr);
946 return dsz;
947 }
948
949 /*
950 * tipc_link_send(): same as tipc_link_send_buf(), but the link to use has
951 * not been selected yet, and the the owner node is not locked
952 * Called by TIPC internal users, e.g. the name distributor
953 */
954
tipc_link_send(struct sk_buff * buf,u32 dest,u32 selector)955 int tipc_link_send(struct sk_buff *buf, u32 dest, u32 selector)
956 {
957 struct tipc_link *l_ptr;
958 struct tipc_node *n_ptr;
959 int res = -ELINKCONG;
960
961 read_lock_bh(&tipc_net_lock);
962 n_ptr = tipc_node_find(dest);
963 if (n_ptr) {
964 tipc_node_lock(n_ptr);
965 l_ptr = n_ptr->active_links[selector & 1];
966 if (l_ptr)
967 res = tipc_link_send_buf(l_ptr, buf);
968 else
969 kfree_skb(buf);
970 tipc_node_unlock(n_ptr);
971 } else {
972 kfree_skb(buf);
973 }
974 read_unlock_bh(&tipc_net_lock);
975 return res;
976 }
977
978 /*
979 * tipc_link_send_names - send name table entries to new neighbor
980 *
981 * Send routine for bulk delivery of name table messages when contact
982 * with a new neighbor occurs. No link congestion checking is performed
983 * because name table messages *must* be delivered. The messages must be
984 * small enough not to require fragmentation.
985 * Called without any locks held.
986 */
987
tipc_link_send_names(struct list_head * message_list,u32 dest)988 void tipc_link_send_names(struct list_head *message_list, u32 dest)
989 {
990 struct tipc_node *n_ptr;
991 struct tipc_link *l_ptr;
992 struct sk_buff *buf;
993 struct sk_buff *temp_buf;
994
995 if (list_empty(message_list))
996 return;
997
998 read_lock_bh(&tipc_net_lock);
999 n_ptr = tipc_node_find(dest);
1000 if (n_ptr) {
1001 tipc_node_lock(n_ptr);
1002 l_ptr = n_ptr->active_links[0];
1003 if (l_ptr) {
1004 /* convert circular list to linear list */
1005 ((struct sk_buff *)message_list->prev)->next = NULL;
1006 link_add_chain_to_outqueue(l_ptr,
1007 (struct sk_buff *)message_list->next, 0);
1008 tipc_link_push_queue(l_ptr);
1009 INIT_LIST_HEAD(message_list);
1010 }
1011 tipc_node_unlock(n_ptr);
1012 }
1013 read_unlock_bh(&tipc_net_lock);
1014
1015 /* discard the messages if they couldn't be sent */
1016
1017 list_for_each_safe(buf, temp_buf, ((struct sk_buff *)message_list)) {
1018 list_del((struct list_head *)buf);
1019 kfree_skb(buf);
1020 }
1021 }
1022
1023 /*
1024 * link_send_buf_fast: Entry for data messages where the
1025 * destination link is known and the header is complete,
1026 * inclusive total message length. Very time critical.
1027 * Link is locked. Returns user data length.
1028 */
1029
link_send_buf_fast(struct tipc_link * l_ptr,struct sk_buff * buf,u32 * used_max_pkt)1030 static int link_send_buf_fast(struct tipc_link *l_ptr, struct sk_buff *buf,
1031 u32 *used_max_pkt)
1032 {
1033 struct tipc_msg *msg = buf_msg(buf);
1034 int res = msg_data_sz(msg);
1035
1036 if (likely(!link_congested(l_ptr))) {
1037 if (likely(msg_size(msg) <= l_ptr->max_pkt)) {
1038 if (likely(list_empty(&l_ptr->b_ptr->cong_links))) {
1039 link_add_to_outqueue(l_ptr, buf, msg);
1040 if (likely(tipc_bearer_send(l_ptr->b_ptr, buf,
1041 &l_ptr->media_addr))) {
1042 l_ptr->unacked_window = 0;
1043 return res;
1044 }
1045 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr);
1046 l_ptr->stats.bearer_congs++;
1047 l_ptr->next_out = buf;
1048 return res;
1049 }
1050 } else
1051 *used_max_pkt = l_ptr->max_pkt;
1052 }
1053 return tipc_link_send_buf(l_ptr, buf); /* All other cases */
1054 }
1055
1056 /*
1057 * tipc_send_buf_fast: Entry for data messages where the
1058 * destination node is known and the header is complete,
1059 * inclusive total message length.
1060 * Returns user data length.
1061 */
tipc_send_buf_fast(struct sk_buff * buf,u32 destnode)1062 int tipc_send_buf_fast(struct sk_buff *buf, u32 destnode)
1063 {
1064 struct tipc_link *l_ptr;
1065 struct tipc_node *n_ptr;
1066 int res;
1067 u32 selector = msg_origport(buf_msg(buf)) & 1;
1068 u32 dummy;
1069
1070 read_lock_bh(&tipc_net_lock);
1071 n_ptr = tipc_node_find(destnode);
1072 if (likely(n_ptr)) {
1073 tipc_node_lock(n_ptr);
1074 l_ptr = n_ptr->active_links[selector];
1075 if (likely(l_ptr)) {
1076 res = link_send_buf_fast(l_ptr, buf, &dummy);
1077 tipc_node_unlock(n_ptr);
1078 read_unlock_bh(&tipc_net_lock);
1079 return res;
1080 }
1081 tipc_node_unlock(n_ptr);
1082 }
1083 read_unlock_bh(&tipc_net_lock);
1084 res = msg_data_sz(buf_msg(buf));
1085 tipc_reject_msg(buf, TIPC_ERR_NO_NODE);
1086 return res;
1087 }
1088
1089
1090 /*
1091 * tipc_link_send_sections_fast: Entry for messages where the
1092 * destination processor is known and the header is complete,
1093 * except for total message length.
1094 * Returns user data length or errno.
1095 */
tipc_link_send_sections_fast(struct tipc_port * sender,struct iovec const * msg_sect,const u32 num_sect,unsigned int total_len,u32 destaddr)1096 int tipc_link_send_sections_fast(struct tipc_port *sender,
1097 struct iovec const *msg_sect,
1098 const u32 num_sect,
1099 unsigned int total_len,
1100 u32 destaddr)
1101 {
1102 struct tipc_msg *hdr = &sender->phdr;
1103 struct tipc_link *l_ptr;
1104 struct sk_buff *buf;
1105 struct tipc_node *node;
1106 int res;
1107 u32 selector = msg_origport(hdr) & 1;
1108
1109 again:
1110 /*
1111 * Try building message using port's max_pkt hint.
1112 * (Must not hold any locks while building message.)
1113 */
1114
1115 res = tipc_msg_build(hdr, msg_sect, num_sect, total_len,
1116 sender->max_pkt, !sender->user_port, &buf);
1117
1118 read_lock_bh(&tipc_net_lock);
1119 node = tipc_node_find(destaddr);
1120 if (likely(node)) {
1121 tipc_node_lock(node);
1122 l_ptr = node->active_links[selector];
1123 if (likely(l_ptr)) {
1124 if (likely(buf)) {
1125 res = link_send_buf_fast(l_ptr, buf,
1126 &sender->max_pkt);
1127 exit:
1128 tipc_node_unlock(node);
1129 read_unlock_bh(&tipc_net_lock);
1130 return res;
1131 }
1132
1133 /* Exit if build request was invalid */
1134
1135 if (unlikely(res < 0))
1136 goto exit;
1137
1138 /* Exit if link (or bearer) is congested */
1139
1140 if (link_congested(l_ptr) ||
1141 !list_empty(&l_ptr->b_ptr->cong_links)) {
1142 res = link_schedule_port(l_ptr,
1143 sender->ref, res);
1144 goto exit;
1145 }
1146
1147 /*
1148 * Message size exceeds max_pkt hint; update hint,
1149 * then re-try fast path or fragment the message
1150 */
1151
1152 sender->max_pkt = l_ptr->max_pkt;
1153 tipc_node_unlock(node);
1154 read_unlock_bh(&tipc_net_lock);
1155
1156
1157 if ((msg_hdr_sz(hdr) + res) <= sender->max_pkt)
1158 goto again;
1159
1160 return link_send_sections_long(sender, msg_sect,
1161 num_sect, total_len,
1162 destaddr);
1163 }
1164 tipc_node_unlock(node);
1165 }
1166 read_unlock_bh(&tipc_net_lock);
1167
1168 /* Couldn't find a link to the destination node */
1169
1170 if (buf)
1171 return tipc_reject_msg(buf, TIPC_ERR_NO_NODE);
1172 if (res >= 0)
1173 return tipc_port_reject_sections(sender, hdr, msg_sect, num_sect,
1174 total_len, TIPC_ERR_NO_NODE);
1175 return res;
1176 }
1177
1178 /*
1179 * link_send_sections_long(): Entry for long messages where the
1180 * destination node is known and the header is complete,
1181 * inclusive total message length.
1182 * Link and bearer congestion status have been checked to be ok,
1183 * and are ignored if they change.
1184 *
1185 * Note that fragments do not use the full link MTU so that they won't have
1186 * to undergo refragmentation if link changeover causes them to be sent
1187 * over another link with an additional tunnel header added as prefix.
1188 * (Refragmentation will still occur if the other link has a smaller MTU.)
1189 *
1190 * Returns user data length or errno.
1191 */
link_send_sections_long(struct tipc_port * sender,struct iovec const * msg_sect,u32 num_sect,unsigned int total_len,u32 destaddr)1192 static int link_send_sections_long(struct tipc_port *sender,
1193 struct iovec const *msg_sect,
1194 u32 num_sect,
1195 unsigned int total_len,
1196 u32 destaddr)
1197 {
1198 struct tipc_link *l_ptr;
1199 struct tipc_node *node;
1200 struct tipc_msg *hdr = &sender->phdr;
1201 u32 dsz = total_len;
1202 u32 max_pkt, fragm_sz, rest;
1203 struct tipc_msg fragm_hdr;
1204 struct sk_buff *buf, *buf_chain, *prev;
1205 u32 fragm_crs, fragm_rest, hsz, sect_rest;
1206 const unchar *sect_crs;
1207 int curr_sect;
1208 u32 fragm_no;
1209
1210 again:
1211 fragm_no = 1;
1212 max_pkt = sender->max_pkt - INT_H_SIZE;
1213 /* leave room for tunnel header in case of link changeover */
1214 fragm_sz = max_pkt - INT_H_SIZE;
1215 /* leave room for fragmentation header in each fragment */
1216 rest = dsz;
1217 fragm_crs = 0;
1218 fragm_rest = 0;
1219 sect_rest = 0;
1220 sect_crs = NULL;
1221 curr_sect = -1;
1222
1223 /* Prepare reusable fragment header: */
1224
1225 tipc_msg_init(&fragm_hdr, MSG_FRAGMENTER, FIRST_FRAGMENT,
1226 INT_H_SIZE, msg_destnode(hdr));
1227 msg_set_size(&fragm_hdr, max_pkt);
1228 msg_set_fragm_no(&fragm_hdr, 1);
1229
1230 /* Prepare header of first fragment: */
1231
1232 buf_chain = buf = tipc_buf_acquire(max_pkt);
1233 if (!buf)
1234 return -ENOMEM;
1235 buf->next = NULL;
1236 skb_copy_to_linear_data(buf, &fragm_hdr, INT_H_SIZE);
1237 hsz = msg_hdr_sz(hdr);
1238 skb_copy_to_linear_data_offset(buf, INT_H_SIZE, hdr, hsz);
1239
1240 /* Chop up message: */
1241
1242 fragm_crs = INT_H_SIZE + hsz;
1243 fragm_rest = fragm_sz - hsz;
1244
1245 do { /* For all sections */
1246 u32 sz;
1247
1248 if (!sect_rest) {
1249 sect_rest = msg_sect[++curr_sect].iov_len;
1250 sect_crs = (const unchar *)msg_sect[curr_sect].iov_base;
1251 }
1252
1253 if (sect_rest < fragm_rest)
1254 sz = sect_rest;
1255 else
1256 sz = fragm_rest;
1257
1258 if (likely(!sender->user_port)) {
1259 if (copy_from_user(buf->data + fragm_crs, sect_crs, sz)) {
1260 error:
1261 for (; buf_chain; buf_chain = buf) {
1262 buf = buf_chain->next;
1263 kfree_skb(buf_chain);
1264 }
1265 return -EFAULT;
1266 }
1267 } else
1268 skb_copy_to_linear_data_offset(buf, fragm_crs,
1269 sect_crs, sz);
1270 sect_crs += sz;
1271 sect_rest -= sz;
1272 fragm_crs += sz;
1273 fragm_rest -= sz;
1274 rest -= sz;
1275
1276 if (!fragm_rest && rest) {
1277
1278 /* Initiate new fragment: */
1279 if (rest <= fragm_sz) {
1280 fragm_sz = rest;
1281 msg_set_type(&fragm_hdr, LAST_FRAGMENT);
1282 } else {
1283 msg_set_type(&fragm_hdr, FRAGMENT);
1284 }
1285 msg_set_size(&fragm_hdr, fragm_sz + INT_H_SIZE);
1286 msg_set_fragm_no(&fragm_hdr, ++fragm_no);
1287 prev = buf;
1288 buf = tipc_buf_acquire(fragm_sz + INT_H_SIZE);
1289 if (!buf)
1290 goto error;
1291
1292 buf->next = NULL;
1293 prev->next = buf;
1294 skb_copy_to_linear_data(buf, &fragm_hdr, INT_H_SIZE);
1295 fragm_crs = INT_H_SIZE;
1296 fragm_rest = fragm_sz;
1297 }
1298 } while (rest > 0);
1299
1300 /*
1301 * Now we have a buffer chain. Select a link and check
1302 * that packet size is still OK
1303 */
1304 node = tipc_node_find(destaddr);
1305 if (likely(node)) {
1306 tipc_node_lock(node);
1307 l_ptr = node->active_links[sender->ref & 1];
1308 if (!l_ptr) {
1309 tipc_node_unlock(node);
1310 goto reject;
1311 }
1312 if (l_ptr->max_pkt < max_pkt) {
1313 sender->max_pkt = l_ptr->max_pkt;
1314 tipc_node_unlock(node);
1315 for (; buf_chain; buf_chain = buf) {
1316 buf = buf_chain->next;
1317 kfree_skb(buf_chain);
1318 }
1319 goto again;
1320 }
1321 } else {
1322 reject:
1323 for (; buf_chain; buf_chain = buf) {
1324 buf = buf_chain->next;
1325 kfree_skb(buf_chain);
1326 }
1327 return tipc_port_reject_sections(sender, hdr, msg_sect, num_sect,
1328 total_len, TIPC_ERR_NO_NODE);
1329 }
1330
1331 /* Append chain of fragments to send queue & send them */
1332
1333 l_ptr->long_msg_seq_no++;
1334 link_add_chain_to_outqueue(l_ptr, buf_chain, l_ptr->long_msg_seq_no);
1335 l_ptr->stats.sent_fragments += fragm_no;
1336 l_ptr->stats.sent_fragmented++;
1337 tipc_link_push_queue(l_ptr);
1338 tipc_node_unlock(node);
1339 return dsz;
1340 }
1341
1342 /*
1343 * tipc_link_push_packet: Push one unsent packet to the media
1344 */
tipc_link_push_packet(struct tipc_link * l_ptr)1345 u32 tipc_link_push_packet(struct tipc_link *l_ptr)
1346 {
1347 struct sk_buff *buf = l_ptr->first_out;
1348 u32 r_q_size = l_ptr->retransm_queue_size;
1349 u32 r_q_head = l_ptr->retransm_queue_head;
1350
1351 /* Step to position where retransmission failed, if any, */
1352 /* consider that buffers may have been released in meantime */
1353
1354 if (r_q_size && buf) {
1355 u32 last = lesser(mod(r_q_head + r_q_size),
1356 link_last_sent(l_ptr));
1357 u32 first = buf_seqno(buf);
1358
1359 while (buf && less(first, r_q_head)) {
1360 first = mod(first + 1);
1361 buf = buf->next;
1362 }
1363 l_ptr->retransm_queue_head = r_q_head = first;
1364 l_ptr->retransm_queue_size = r_q_size = mod(last - first);
1365 }
1366
1367 /* Continue retransmission now, if there is anything: */
1368
1369 if (r_q_size && buf) {
1370 msg_set_ack(buf_msg(buf), mod(l_ptr->next_in_no - 1));
1371 msg_set_bcast_ack(buf_msg(buf), l_ptr->owner->bclink.last_in);
1372 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) {
1373 l_ptr->retransm_queue_head = mod(++r_q_head);
1374 l_ptr->retransm_queue_size = --r_q_size;
1375 l_ptr->stats.retransmitted++;
1376 return 0;
1377 } else {
1378 l_ptr->stats.bearer_congs++;
1379 return PUSH_FAILED;
1380 }
1381 }
1382
1383 /* Send deferred protocol message, if any: */
1384
1385 buf = l_ptr->proto_msg_queue;
1386 if (buf) {
1387 msg_set_ack(buf_msg(buf), mod(l_ptr->next_in_no - 1));
1388 msg_set_bcast_ack(buf_msg(buf), l_ptr->owner->bclink.last_in);
1389 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) {
1390 l_ptr->unacked_window = 0;
1391 kfree_skb(buf);
1392 l_ptr->proto_msg_queue = NULL;
1393 return 0;
1394 } else {
1395 l_ptr->stats.bearer_congs++;
1396 return PUSH_FAILED;
1397 }
1398 }
1399
1400 /* Send one deferred data message, if send window not full: */
1401
1402 buf = l_ptr->next_out;
1403 if (buf) {
1404 struct tipc_msg *msg = buf_msg(buf);
1405 u32 next = msg_seqno(msg);
1406 u32 first = buf_seqno(l_ptr->first_out);
1407
1408 if (mod(next - first) < l_ptr->queue_limit[0]) {
1409 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
1410 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1411 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) {
1412 if (msg_user(msg) == MSG_BUNDLER)
1413 msg_set_type(msg, CLOSED_MSG);
1414 l_ptr->next_out = buf->next;
1415 return 0;
1416 } else {
1417 l_ptr->stats.bearer_congs++;
1418 return PUSH_FAILED;
1419 }
1420 }
1421 }
1422 return PUSH_FINISHED;
1423 }
1424
1425 /*
1426 * push_queue(): push out the unsent messages of a link where
1427 * congestion has abated. Node is locked
1428 */
tipc_link_push_queue(struct tipc_link * l_ptr)1429 void tipc_link_push_queue(struct tipc_link *l_ptr)
1430 {
1431 u32 res;
1432
1433 if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr))
1434 return;
1435
1436 do {
1437 res = tipc_link_push_packet(l_ptr);
1438 } while (!res);
1439
1440 if (res == PUSH_FAILED)
1441 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr);
1442 }
1443
link_reset_all(unsigned long addr)1444 static void link_reset_all(unsigned long addr)
1445 {
1446 struct tipc_node *n_ptr;
1447 char addr_string[16];
1448 u32 i;
1449
1450 read_lock_bh(&tipc_net_lock);
1451 n_ptr = tipc_node_find((u32)addr);
1452 if (!n_ptr) {
1453 read_unlock_bh(&tipc_net_lock);
1454 return; /* node no longer exists */
1455 }
1456
1457 tipc_node_lock(n_ptr);
1458
1459 warn("Resetting all links to %s\n",
1460 tipc_addr_string_fill(addr_string, n_ptr->addr));
1461
1462 for (i = 0; i < MAX_BEARERS; i++) {
1463 if (n_ptr->links[i]) {
1464 link_print(n_ptr->links[i], "Resetting link\n");
1465 tipc_link_reset(n_ptr->links[i]);
1466 }
1467 }
1468
1469 tipc_node_unlock(n_ptr);
1470 read_unlock_bh(&tipc_net_lock);
1471 }
1472
link_retransmit_failure(struct tipc_link * l_ptr,struct sk_buff * buf)1473 static void link_retransmit_failure(struct tipc_link *l_ptr,
1474 struct sk_buff *buf)
1475 {
1476 struct tipc_msg *msg = buf_msg(buf);
1477
1478 warn("Retransmission failure on link <%s>\n", l_ptr->name);
1479
1480 if (l_ptr->addr) {
1481
1482 /* Handle failure on standard link */
1483
1484 link_print(l_ptr, "Resetting link\n");
1485 tipc_link_reset(l_ptr);
1486
1487 } else {
1488
1489 /* Handle failure on broadcast link */
1490
1491 struct tipc_node *n_ptr;
1492 char addr_string[16];
1493
1494 info("Msg seq number: %u, ", msg_seqno(msg));
1495 info("Outstanding acks: %lu\n",
1496 (unsigned long) TIPC_SKB_CB(buf)->handle);
1497
1498 n_ptr = tipc_bclink_retransmit_to();
1499 tipc_node_lock(n_ptr);
1500
1501 tipc_addr_string_fill(addr_string, n_ptr->addr);
1502 info("Broadcast link info for %s\n", addr_string);
1503 info("Supportable: %d, ", n_ptr->bclink.supportable);
1504 info("Supported: %d, ", n_ptr->bclink.supported);
1505 info("Acked: %u\n", n_ptr->bclink.acked);
1506 info("Last in: %u, ", n_ptr->bclink.last_in);
1507 info("Oos state: %u, ", n_ptr->bclink.oos_state);
1508 info("Last sent: %u\n", n_ptr->bclink.last_sent);
1509
1510 tipc_k_signal((Handler)link_reset_all, (unsigned long)n_ptr->addr);
1511
1512 tipc_node_unlock(n_ptr);
1513
1514 l_ptr->stale_count = 0;
1515 }
1516 }
1517
tipc_link_retransmit(struct tipc_link * l_ptr,struct sk_buff * buf,u32 retransmits)1518 void tipc_link_retransmit(struct tipc_link *l_ptr, struct sk_buff *buf,
1519 u32 retransmits)
1520 {
1521 struct tipc_msg *msg;
1522
1523 if (!buf)
1524 return;
1525
1526 msg = buf_msg(buf);
1527
1528 if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr)) {
1529 if (l_ptr->retransm_queue_size == 0) {
1530 l_ptr->retransm_queue_head = msg_seqno(msg);
1531 l_ptr->retransm_queue_size = retransmits;
1532 } else {
1533 err("Unexpected retransmit on link %s (qsize=%d)\n",
1534 l_ptr->name, l_ptr->retransm_queue_size);
1535 }
1536 return;
1537 } else {
1538 /* Detect repeated retransmit failures on uncongested bearer */
1539
1540 if (l_ptr->last_retransmitted == msg_seqno(msg)) {
1541 if (++l_ptr->stale_count > 100) {
1542 link_retransmit_failure(l_ptr, buf);
1543 return;
1544 }
1545 } else {
1546 l_ptr->last_retransmitted = msg_seqno(msg);
1547 l_ptr->stale_count = 1;
1548 }
1549 }
1550
1551 while (retransmits && (buf != l_ptr->next_out) && buf) {
1552 msg = buf_msg(buf);
1553 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
1554 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1555 if (tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) {
1556 buf = buf->next;
1557 retransmits--;
1558 l_ptr->stats.retransmitted++;
1559 } else {
1560 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr);
1561 l_ptr->stats.bearer_congs++;
1562 l_ptr->retransm_queue_head = buf_seqno(buf);
1563 l_ptr->retransm_queue_size = retransmits;
1564 return;
1565 }
1566 }
1567
1568 l_ptr->retransm_queue_head = l_ptr->retransm_queue_size = 0;
1569 }
1570
1571 /**
1572 * link_insert_deferred_queue - insert deferred messages back into receive chain
1573 */
1574
link_insert_deferred_queue(struct tipc_link * l_ptr,struct sk_buff * buf)1575 static struct sk_buff *link_insert_deferred_queue(struct tipc_link *l_ptr,
1576 struct sk_buff *buf)
1577 {
1578 u32 seq_no;
1579
1580 if (l_ptr->oldest_deferred_in == NULL)
1581 return buf;
1582
1583 seq_no = buf_seqno(l_ptr->oldest_deferred_in);
1584 if (seq_no == mod(l_ptr->next_in_no)) {
1585 l_ptr->newest_deferred_in->next = buf;
1586 buf = l_ptr->oldest_deferred_in;
1587 l_ptr->oldest_deferred_in = NULL;
1588 l_ptr->deferred_inqueue_sz = 0;
1589 }
1590 return buf;
1591 }
1592
1593 /**
1594 * link_recv_buf_validate - validate basic format of received message
1595 *
1596 * This routine ensures a TIPC message has an acceptable header, and at least
1597 * as much data as the header indicates it should. The routine also ensures
1598 * that the entire message header is stored in the main fragment of the message
1599 * buffer, to simplify future access to message header fields.
1600 *
1601 * Note: Having extra info present in the message header or data areas is OK.
1602 * TIPC will ignore the excess, under the assumption that it is optional info
1603 * introduced by a later release of the protocol.
1604 */
1605
link_recv_buf_validate(struct sk_buff * buf)1606 static int link_recv_buf_validate(struct sk_buff *buf)
1607 {
1608 static u32 min_data_hdr_size[8] = {
1609 SHORT_H_SIZE, MCAST_H_SIZE, NAMED_H_SIZE, BASIC_H_SIZE,
1610 MAX_H_SIZE, MAX_H_SIZE, MAX_H_SIZE, MAX_H_SIZE
1611 };
1612
1613 struct tipc_msg *msg;
1614 u32 tipc_hdr[2];
1615 u32 size;
1616 u32 hdr_size;
1617 u32 min_hdr_size;
1618
1619 if (unlikely(buf->len < MIN_H_SIZE))
1620 return 0;
1621
1622 msg = skb_header_pointer(buf, 0, sizeof(tipc_hdr), tipc_hdr);
1623 if (msg == NULL)
1624 return 0;
1625
1626 if (unlikely(msg_version(msg) != TIPC_VERSION))
1627 return 0;
1628
1629 size = msg_size(msg);
1630 hdr_size = msg_hdr_sz(msg);
1631 min_hdr_size = msg_isdata(msg) ?
1632 min_data_hdr_size[msg_type(msg)] : INT_H_SIZE;
1633
1634 if (unlikely((hdr_size < min_hdr_size) ||
1635 (size < hdr_size) ||
1636 (buf->len < size) ||
1637 (size - hdr_size > TIPC_MAX_USER_MSG_SIZE)))
1638 return 0;
1639
1640 return pskb_may_pull(buf, hdr_size);
1641 }
1642
1643 /**
1644 * tipc_recv_msg - process TIPC messages arriving from off-node
1645 * @head: pointer to message buffer chain
1646 * @tb_ptr: pointer to bearer message arrived on
1647 *
1648 * Invoked with no locks held. Bearer pointer must point to a valid bearer
1649 * structure (i.e. cannot be NULL), but bearer can be inactive.
1650 */
1651
tipc_recv_msg(struct sk_buff * head,struct tipc_bearer * b_ptr)1652 void tipc_recv_msg(struct sk_buff *head, struct tipc_bearer *b_ptr)
1653 {
1654 read_lock_bh(&tipc_net_lock);
1655 while (head) {
1656 struct tipc_node *n_ptr;
1657 struct tipc_link *l_ptr;
1658 struct sk_buff *crs;
1659 struct sk_buff *buf = head;
1660 struct tipc_msg *msg;
1661 u32 seq_no;
1662 u32 ackd;
1663 u32 released = 0;
1664 int type;
1665
1666 head = head->next;
1667
1668 /* Ensure bearer is still enabled */
1669
1670 if (unlikely(!b_ptr->active))
1671 goto cont;
1672
1673 /* Ensure message is well-formed */
1674
1675 if (unlikely(!link_recv_buf_validate(buf)))
1676 goto cont;
1677
1678 /* Ensure message data is a single contiguous unit */
1679
1680 if (unlikely(skb_linearize(buf)))
1681 goto cont;
1682
1683 /* Handle arrival of a non-unicast link message */
1684
1685 msg = buf_msg(buf);
1686
1687 if (unlikely(msg_non_seq(msg))) {
1688 if (msg_user(msg) == LINK_CONFIG)
1689 tipc_disc_recv_msg(buf, b_ptr);
1690 else
1691 tipc_bclink_recv_pkt(buf);
1692 continue;
1693 }
1694
1695 /* Discard unicast link messages destined for another node */
1696
1697 if (unlikely(!msg_short(msg) &&
1698 (msg_destnode(msg) != tipc_own_addr)))
1699 goto cont;
1700
1701 /* Locate neighboring node that sent message */
1702
1703 n_ptr = tipc_node_find(msg_prevnode(msg));
1704 if (unlikely(!n_ptr))
1705 goto cont;
1706 tipc_node_lock(n_ptr);
1707
1708 /* Locate unicast link endpoint that should handle message */
1709
1710 l_ptr = n_ptr->links[b_ptr->identity];
1711 if (unlikely(!l_ptr)) {
1712 tipc_node_unlock(n_ptr);
1713 goto cont;
1714 }
1715
1716 /* Verify that communication with node is currently allowed */
1717
1718 if ((n_ptr->block_setup & WAIT_PEER_DOWN) &&
1719 msg_user(msg) == LINK_PROTOCOL &&
1720 (msg_type(msg) == RESET_MSG ||
1721 msg_type(msg) == ACTIVATE_MSG) &&
1722 !msg_redundant_link(msg))
1723 n_ptr->block_setup &= ~WAIT_PEER_DOWN;
1724
1725 if (n_ptr->block_setup) {
1726 tipc_node_unlock(n_ptr);
1727 goto cont;
1728 }
1729
1730 /* Validate message sequence number info */
1731
1732 seq_no = msg_seqno(msg);
1733 ackd = msg_ack(msg);
1734
1735 /* Release acked messages */
1736
1737 if (n_ptr->bclink.supported)
1738 tipc_bclink_acknowledge(n_ptr, msg_bcast_ack(msg));
1739
1740 crs = l_ptr->first_out;
1741 while ((crs != l_ptr->next_out) &&
1742 less_eq(buf_seqno(crs), ackd)) {
1743 struct sk_buff *next = crs->next;
1744
1745 kfree_skb(crs);
1746 crs = next;
1747 released++;
1748 }
1749 if (released) {
1750 l_ptr->first_out = crs;
1751 l_ptr->out_queue_size -= released;
1752 }
1753
1754 /* Try sending any messages link endpoint has pending */
1755
1756 if (unlikely(l_ptr->next_out))
1757 tipc_link_push_queue(l_ptr);
1758 if (unlikely(!list_empty(&l_ptr->waiting_ports)))
1759 tipc_link_wakeup_ports(l_ptr, 0);
1760 if (unlikely(++l_ptr->unacked_window >= TIPC_MIN_LINK_WIN)) {
1761 l_ptr->stats.sent_acks++;
1762 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, 0, 0);
1763 }
1764
1765 /* Now (finally!) process the incoming message */
1766
1767 protocol_check:
1768 if (likely(link_working_working(l_ptr))) {
1769 if (likely(seq_no == mod(l_ptr->next_in_no))) {
1770 l_ptr->next_in_no++;
1771 if (unlikely(l_ptr->oldest_deferred_in))
1772 head = link_insert_deferred_queue(l_ptr,
1773 head);
1774 deliver:
1775 if (likely(msg_isdata(msg))) {
1776 tipc_node_unlock(n_ptr);
1777 tipc_port_recv_msg(buf);
1778 continue;
1779 }
1780 switch (msg_user(msg)) {
1781 int ret;
1782 case MSG_BUNDLER:
1783 l_ptr->stats.recv_bundles++;
1784 l_ptr->stats.recv_bundled +=
1785 msg_msgcnt(msg);
1786 tipc_node_unlock(n_ptr);
1787 tipc_link_recv_bundle(buf);
1788 continue;
1789 case NAME_DISTRIBUTOR:
1790 tipc_node_unlock(n_ptr);
1791 tipc_named_recv(buf);
1792 continue;
1793 case CONN_MANAGER:
1794 tipc_node_unlock(n_ptr);
1795 tipc_port_recv_proto_msg(buf);
1796 continue;
1797 case MSG_FRAGMENTER:
1798 l_ptr->stats.recv_fragments++;
1799 ret = tipc_link_recv_fragment(
1800 &l_ptr->defragm_buf,
1801 &buf, &msg);
1802 if (ret == 1) {
1803 l_ptr->stats.recv_fragmented++;
1804 goto deliver;
1805 }
1806 if (ret == -1)
1807 l_ptr->next_in_no--;
1808 break;
1809 case CHANGEOVER_PROTOCOL:
1810 type = msg_type(msg);
1811 if (link_recv_changeover_msg(&l_ptr,
1812 &buf)) {
1813 msg = buf_msg(buf);
1814 seq_no = msg_seqno(msg);
1815 if (type == ORIGINAL_MSG)
1816 goto deliver;
1817 goto protocol_check;
1818 }
1819 break;
1820 default:
1821 kfree_skb(buf);
1822 buf = NULL;
1823 break;
1824 }
1825 tipc_node_unlock(n_ptr);
1826 tipc_net_route_msg(buf);
1827 continue;
1828 }
1829 link_handle_out_of_seq_msg(l_ptr, buf);
1830 head = link_insert_deferred_queue(l_ptr, head);
1831 tipc_node_unlock(n_ptr);
1832 continue;
1833 }
1834
1835 if (msg_user(msg) == LINK_PROTOCOL) {
1836 link_recv_proto_msg(l_ptr, buf);
1837 head = link_insert_deferred_queue(l_ptr, head);
1838 tipc_node_unlock(n_ptr);
1839 continue;
1840 }
1841 link_state_event(l_ptr, TRAFFIC_MSG_EVT);
1842
1843 if (link_working_working(l_ptr)) {
1844 /* Re-insert in front of queue */
1845 buf->next = head;
1846 head = buf;
1847 tipc_node_unlock(n_ptr);
1848 continue;
1849 }
1850 tipc_node_unlock(n_ptr);
1851 cont:
1852 kfree_skb(buf);
1853 }
1854 read_unlock_bh(&tipc_net_lock);
1855 }
1856
1857 /*
1858 * tipc_link_defer_pkt - Add out-of-sequence message to deferred reception queue
1859 *
1860 * Returns increase in queue length (i.e. 0 or 1)
1861 */
1862
tipc_link_defer_pkt(struct sk_buff ** head,struct sk_buff ** tail,struct sk_buff * buf)1863 u32 tipc_link_defer_pkt(struct sk_buff **head, struct sk_buff **tail,
1864 struct sk_buff *buf)
1865 {
1866 struct sk_buff *queue_buf;
1867 struct sk_buff **prev;
1868 u32 seq_no = buf_seqno(buf);
1869
1870 buf->next = NULL;
1871
1872 /* Empty queue ? */
1873 if (*head == NULL) {
1874 *head = *tail = buf;
1875 return 1;
1876 }
1877
1878 /* Last ? */
1879 if (less(buf_seqno(*tail), seq_no)) {
1880 (*tail)->next = buf;
1881 *tail = buf;
1882 return 1;
1883 }
1884
1885 /* Locate insertion point in queue, then insert; discard if duplicate */
1886 prev = head;
1887 queue_buf = *head;
1888 for (;;) {
1889 u32 curr_seqno = buf_seqno(queue_buf);
1890
1891 if (seq_no == curr_seqno) {
1892 kfree_skb(buf);
1893 return 0;
1894 }
1895
1896 if (less(seq_no, curr_seqno))
1897 break;
1898
1899 prev = &queue_buf->next;
1900 queue_buf = queue_buf->next;
1901 }
1902
1903 buf->next = queue_buf;
1904 *prev = buf;
1905 return 1;
1906 }
1907
1908 /*
1909 * link_handle_out_of_seq_msg - handle arrival of out-of-sequence packet
1910 */
1911
link_handle_out_of_seq_msg(struct tipc_link * l_ptr,struct sk_buff * buf)1912 static void link_handle_out_of_seq_msg(struct tipc_link *l_ptr,
1913 struct sk_buff *buf)
1914 {
1915 u32 seq_no = buf_seqno(buf);
1916
1917 if (likely(msg_user(buf_msg(buf)) == LINK_PROTOCOL)) {
1918 link_recv_proto_msg(l_ptr, buf);
1919 return;
1920 }
1921
1922 /* Record OOS packet arrival (force mismatch on next timeout) */
1923
1924 l_ptr->checkpoint--;
1925
1926 /*
1927 * Discard packet if a duplicate; otherwise add it to deferred queue
1928 * and notify peer of gap as per protocol specification
1929 */
1930
1931 if (less(seq_no, mod(l_ptr->next_in_no))) {
1932 l_ptr->stats.duplicates++;
1933 kfree_skb(buf);
1934 return;
1935 }
1936
1937 if (tipc_link_defer_pkt(&l_ptr->oldest_deferred_in,
1938 &l_ptr->newest_deferred_in, buf)) {
1939 l_ptr->deferred_inqueue_sz++;
1940 l_ptr->stats.deferred_recv++;
1941 if ((l_ptr->deferred_inqueue_sz % 16) == 1)
1942 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, 0, 0);
1943 } else
1944 l_ptr->stats.duplicates++;
1945 }
1946
1947 /*
1948 * Send protocol message to the other endpoint.
1949 */
tipc_link_send_proto_msg(struct tipc_link * l_ptr,u32 msg_typ,int probe_msg,u32 gap,u32 tolerance,u32 priority,u32 ack_mtu)1950 void tipc_link_send_proto_msg(struct tipc_link *l_ptr, u32 msg_typ,
1951 int probe_msg, u32 gap, u32 tolerance,
1952 u32 priority, u32 ack_mtu)
1953 {
1954 struct sk_buff *buf = NULL;
1955 struct tipc_msg *msg = l_ptr->pmsg;
1956 u32 msg_size = sizeof(l_ptr->proto_msg);
1957 int r_flag;
1958
1959 /* Discard any previous message that was deferred due to congestion */
1960
1961 if (l_ptr->proto_msg_queue) {
1962 kfree_skb(l_ptr->proto_msg_queue);
1963 l_ptr->proto_msg_queue = NULL;
1964 }
1965
1966 if (link_blocked(l_ptr))
1967 return;
1968
1969 /* Abort non-RESET send if communication with node is prohibited */
1970
1971 if ((l_ptr->owner->block_setup) && (msg_typ != RESET_MSG))
1972 return;
1973
1974 /* Create protocol message with "out-of-sequence" sequence number */
1975
1976 msg_set_type(msg, msg_typ);
1977 msg_set_net_plane(msg, l_ptr->b_ptr->net_plane);
1978 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1979 msg_set_last_bcast(msg, tipc_bclink_get_last_sent());
1980
1981 if (msg_typ == STATE_MSG) {
1982 u32 next_sent = mod(l_ptr->next_out_no);
1983
1984 if (!tipc_link_is_up(l_ptr))
1985 return;
1986 if (l_ptr->next_out)
1987 next_sent = buf_seqno(l_ptr->next_out);
1988 msg_set_next_sent(msg, next_sent);
1989 if (l_ptr->oldest_deferred_in) {
1990 u32 rec = buf_seqno(l_ptr->oldest_deferred_in);
1991 gap = mod(rec - mod(l_ptr->next_in_no));
1992 }
1993 msg_set_seq_gap(msg, gap);
1994 if (gap)
1995 l_ptr->stats.sent_nacks++;
1996 msg_set_link_tolerance(msg, tolerance);
1997 msg_set_linkprio(msg, priority);
1998 msg_set_max_pkt(msg, ack_mtu);
1999 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
2000 msg_set_probe(msg, probe_msg != 0);
2001 if (probe_msg) {
2002 u32 mtu = l_ptr->max_pkt;
2003
2004 if ((mtu < l_ptr->max_pkt_target) &&
2005 link_working_working(l_ptr) &&
2006 l_ptr->fsm_msg_cnt) {
2007 msg_size = (mtu + (l_ptr->max_pkt_target - mtu)/2 + 2) & ~3;
2008 if (l_ptr->max_pkt_probes == 10) {
2009 l_ptr->max_pkt_target = (msg_size - 4);
2010 l_ptr->max_pkt_probes = 0;
2011 msg_size = (mtu + (l_ptr->max_pkt_target - mtu)/2 + 2) & ~3;
2012 }
2013 l_ptr->max_pkt_probes++;
2014 }
2015
2016 l_ptr->stats.sent_probes++;
2017 }
2018 l_ptr->stats.sent_states++;
2019 } else { /* RESET_MSG or ACTIVATE_MSG */
2020 msg_set_ack(msg, mod(l_ptr->reset_checkpoint - 1));
2021 msg_set_seq_gap(msg, 0);
2022 msg_set_next_sent(msg, 1);
2023 msg_set_probe(msg, 0);
2024 msg_set_link_tolerance(msg, l_ptr->tolerance);
2025 msg_set_linkprio(msg, l_ptr->priority);
2026 msg_set_max_pkt(msg, l_ptr->max_pkt_target);
2027 }
2028
2029 r_flag = (l_ptr->owner->working_links > tipc_link_is_up(l_ptr));
2030 msg_set_redundant_link(msg, r_flag);
2031 msg_set_linkprio(msg, l_ptr->priority);
2032 msg_set_size(msg, msg_size);
2033
2034 msg_set_seqno(msg, mod(l_ptr->next_out_no + (0xffff/2)));
2035
2036 buf = tipc_buf_acquire(msg_size);
2037 if (!buf)
2038 return;
2039
2040 skb_copy_to_linear_data(buf, msg, sizeof(l_ptr->proto_msg));
2041
2042 /* Defer message if bearer is already congested */
2043
2044 if (tipc_bearer_congested(l_ptr->b_ptr, l_ptr)) {
2045 l_ptr->proto_msg_queue = buf;
2046 return;
2047 }
2048
2049 /* Defer message if attempting to send results in bearer congestion */
2050
2051 if (!tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr)) {
2052 tipc_bearer_schedule(l_ptr->b_ptr, l_ptr);
2053 l_ptr->proto_msg_queue = buf;
2054 l_ptr->stats.bearer_congs++;
2055 return;
2056 }
2057
2058 /* Discard message if it was sent successfully */
2059
2060 l_ptr->unacked_window = 0;
2061 kfree_skb(buf);
2062 }
2063
2064 /*
2065 * Receive protocol message :
2066 * Note that network plane id propagates through the network, and may
2067 * change at any time. The node with lowest address rules
2068 */
2069
link_recv_proto_msg(struct tipc_link * l_ptr,struct sk_buff * buf)2070 static void link_recv_proto_msg(struct tipc_link *l_ptr, struct sk_buff *buf)
2071 {
2072 u32 rec_gap = 0;
2073 u32 max_pkt_info;
2074 u32 max_pkt_ack;
2075 u32 msg_tol;
2076 struct tipc_msg *msg = buf_msg(buf);
2077
2078 if (link_blocked(l_ptr))
2079 goto exit;
2080
2081 /* record unnumbered packet arrival (force mismatch on next timeout) */
2082
2083 l_ptr->checkpoint--;
2084
2085 if (l_ptr->b_ptr->net_plane != msg_net_plane(msg))
2086 if (tipc_own_addr > msg_prevnode(msg))
2087 l_ptr->b_ptr->net_plane = msg_net_plane(msg);
2088
2089 l_ptr->owner->permit_changeover = msg_redundant_link(msg);
2090
2091 switch (msg_type(msg)) {
2092
2093 case RESET_MSG:
2094 if (!link_working_unknown(l_ptr) &&
2095 (l_ptr->peer_session != INVALID_SESSION)) {
2096 if (less_eq(msg_session(msg), l_ptr->peer_session))
2097 break; /* duplicate or old reset: ignore */
2098 }
2099
2100 if (!msg_redundant_link(msg) && (link_working_working(l_ptr) ||
2101 link_working_unknown(l_ptr))) {
2102 /*
2103 * peer has lost contact -- don't allow peer's links
2104 * to reactivate before we recognize loss & clean up
2105 */
2106 l_ptr->owner->block_setup = WAIT_NODE_DOWN;
2107 }
2108
2109 link_state_event(l_ptr, RESET_MSG);
2110
2111 /* fall thru' */
2112 case ACTIVATE_MSG:
2113 /* Update link settings according other endpoint's values */
2114
2115 strcpy((strrchr(l_ptr->name, ':') + 1), (char *)msg_data(msg));
2116
2117 msg_tol = msg_link_tolerance(msg);
2118 if (msg_tol > l_ptr->tolerance)
2119 link_set_supervision_props(l_ptr, msg_tol);
2120
2121 if (msg_linkprio(msg) > l_ptr->priority)
2122 l_ptr->priority = msg_linkprio(msg);
2123
2124 max_pkt_info = msg_max_pkt(msg);
2125 if (max_pkt_info) {
2126 if (max_pkt_info < l_ptr->max_pkt_target)
2127 l_ptr->max_pkt_target = max_pkt_info;
2128 if (l_ptr->max_pkt > l_ptr->max_pkt_target)
2129 l_ptr->max_pkt = l_ptr->max_pkt_target;
2130 } else {
2131 l_ptr->max_pkt = l_ptr->max_pkt_target;
2132 }
2133 l_ptr->owner->bclink.supportable = (max_pkt_info != 0);
2134
2135 /* Synchronize broadcast link info, if not done previously */
2136
2137 if (!tipc_node_is_up(l_ptr->owner)) {
2138 l_ptr->owner->bclink.last_sent =
2139 l_ptr->owner->bclink.last_in =
2140 msg_last_bcast(msg);
2141 l_ptr->owner->bclink.oos_state = 0;
2142 }
2143
2144 l_ptr->peer_session = msg_session(msg);
2145 l_ptr->peer_bearer_id = msg_bearer_id(msg);
2146
2147 if (msg_type(msg) == ACTIVATE_MSG)
2148 link_state_event(l_ptr, ACTIVATE_MSG);
2149 break;
2150 case STATE_MSG:
2151
2152 msg_tol = msg_link_tolerance(msg);
2153 if (msg_tol)
2154 link_set_supervision_props(l_ptr, msg_tol);
2155
2156 if (msg_linkprio(msg) &&
2157 (msg_linkprio(msg) != l_ptr->priority)) {
2158 warn("Resetting link <%s>, priority change %u->%u\n",
2159 l_ptr->name, l_ptr->priority, msg_linkprio(msg));
2160 l_ptr->priority = msg_linkprio(msg);
2161 tipc_link_reset(l_ptr); /* Enforce change to take effect */
2162 break;
2163 }
2164 link_state_event(l_ptr, TRAFFIC_MSG_EVT);
2165 l_ptr->stats.recv_states++;
2166 if (link_reset_unknown(l_ptr))
2167 break;
2168
2169 if (less_eq(mod(l_ptr->next_in_no), msg_next_sent(msg))) {
2170 rec_gap = mod(msg_next_sent(msg) -
2171 mod(l_ptr->next_in_no));
2172 }
2173
2174 max_pkt_ack = msg_max_pkt(msg);
2175 if (max_pkt_ack > l_ptr->max_pkt) {
2176 l_ptr->max_pkt = max_pkt_ack;
2177 l_ptr->max_pkt_probes = 0;
2178 }
2179
2180 max_pkt_ack = 0;
2181 if (msg_probe(msg)) {
2182 l_ptr->stats.recv_probes++;
2183 if (msg_size(msg) > sizeof(l_ptr->proto_msg))
2184 max_pkt_ack = msg_size(msg);
2185 }
2186
2187 /* Protocol message before retransmits, reduce loss risk */
2188
2189 if (l_ptr->owner->bclink.supported)
2190 tipc_bclink_update_link_state(l_ptr->owner,
2191 msg_last_bcast(msg));
2192
2193 if (rec_gap || (msg_probe(msg))) {
2194 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
2195 0, rec_gap, 0, 0, max_pkt_ack);
2196 }
2197 if (msg_seq_gap(msg)) {
2198 l_ptr->stats.recv_nacks++;
2199 tipc_link_retransmit(l_ptr, l_ptr->first_out,
2200 msg_seq_gap(msg));
2201 }
2202 break;
2203 }
2204 exit:
2205 kfree_skb(buf);
2206 }
2207
2208
2209 /*
2210 * tipc_link_tunnel(): Send one message via a link belonging to
2211 * another bearer. Owner node is locked.
2212 */
tipc_link_tunnel(struct tipc_link * l_ptr,struct tipc_msg * tunnel_hdr,struct tipc_msg * msg,u32 selector)2213 static void tipc_link_tunnel(struct tipc_link *l_ptr,
2214 struct tipc_msg *tunnel_hdr,
2215 struct tipc_msg *msg,
2216 u32 selector)
2217 {
2218 struct tipc_link *tunnel;
2219 struct sk_buff *buf;
2220 u32 length = msg_size(msg);
2221
2222 tunnel = l_ptr->owner->active_links[selector & 1];
2223 if (!tipc_link_is_up(tunnel)) {
2224 warn("Link changeover error, "
2225 "tunnel link no longer available\n");
2226 return;
2227 }
2228 msg_set_size(tunnel_hdr, length + INT_H_SIZE);
2229 buf = tipc_buf_acquire(length + INT_H_SIZE);
2230 if (!buf) {
2231 warn("Link changeover error, "
2232 "unable to send tunnel msg\n");
2233 return;
2234 }
2235 skb_copy_to_linear_data(buf, tunnel_hdr, INT_H_SIZE);
2236 skb_copy_to_linear_data_offset(buf, INT_H_SIZE, msg, length);
2237 tipc_link_send_buf(tunnel, buf);
2238 }
2239
2240
2241
2242 /*
2243 * changeover(): Send whole message queue via the remaining link
2244 * Owner node is locked.
2245 */
2246
tipc_link_changeover(struct tipc_link * l_ptr)2247 void tipc_link_changeover(struct tipc_link *l_ptr)
2248 {
2249 u32 msgcount = l_ptr->out_queue_size;
2250 struct sk_buff *crs = l_ptr->first_out;
2251 struct tipc_link *tunnel = l_ptr->owner->active_links[0];
2252 struct tipc_msg tunnel_hdr;
2253 int split_bundles;
2254
2255 if (!tunnel)
2256 return;
2257
2258 if (!l_ptr->owner->permit_changeover) {
2259 warn("Link changeover error, "
2260 "peer did not permit changeover\n");
2261 return;
2262 }
2263
2264 tipc_msg_init(&tunnel_hdr, CHANGEOVER_PROTOCOL,
2265 ORIGINAL_MSG, INT_H_SIZE, l_ptr->addr);
2266 msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id);
2267 msg_set_msgcnt(&tunnel_hdr, msgcount);
2268
2269 if (!l_ptr->first_out) {
2270 struct sk_buff *buf;
2271
2272 buf = tipc_buf_acquire(INT_H_SIZE);
2273 if (buf) {
2274 skb_copy_to_linear_data(buf, &tunnel_hdr, INT_H_SIZE);
2275 msg_set_size(&tunnel_hdr, INT_H_SIZE);
2276 tipc_link_send_buf(tunnel, buf);
2277 } else {
2278 warn("Link changeover error, "
2279 "unable to send changeover msg\n");
2280 }
2281 return;
2282 }
2283
2284 split_bundles = (l_ptr->owner->active_links[0] !=
2285 l_ptr->owner->active_links[1]);
2286
2287 while (crs) {
2288 struct tipc_msg *msg = buf_msg(crs);
2289
2290 if ((msg_user(msg) == MSG_BUNDLER) && split_bundles) {
2291 struct tipc_msg *m = msg_get_wrapped(msg);
2292 unchar *pos = (unchar *)m;
2293
2294 msgcount = msg_msgcnt(msg);
2295 while (msgcount--) {
2296 msg_set_seqno(m, msg_seqno(msg));
2297 tipc_link_tunnel(l_ptr, &tunnel_hdr, m,
2298 msg_link_selector(m));
2299 pos += align(msg_size(m));
2300 m = (struct tipc_msg *)pos;
2301 }
2302 } else {
2303 tipc_link_tunnel(l_ptr, &tunnel_hdr, msg,
2304 msg_link_selector(msg));
2305 }
2306 crs = crs->next;
2307 }
2308 }
2309
tipc_link_send_duplicate(struct tipc_link * l_ptr,struct tipc_link * tunnel)2310 void tipc_link_send_duplicate(struct tipc_link *l_ptr, struct tipc_link *tunnel)
2311 {
2312 struct sk_buff *iter;
2313 struct tipc_msg tunnel_hdr;
2314
2315 tipc_msg_init(&tunnel_hdr, CHANGEOVER_PROTOCOL,
2316 DUPLICATE_MSG, INT_H_SIZE, l_ptr->addr);
2317 msg_set_msgcnt(&tunnel_hdr, l_ptr->out_queue_size);
2318 msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id);
2319 iter = l_ptr->first_out;
2320 while (iter) {
2321 struct sk_buff *outbuf;
2322 struct tipc_msg *msg = buf_msg(iter);
2323 u32 length = msg_size(msg);
2324
2325 if (msg_user(msg) == MSG_BUNDLER)
2326 msg_set_type(msg, CLOSED_MSG);
2327 msg_set_ack(msg, mod(l_ptr->next_in_no - 1)); /* Update */
2328 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
2329 msg_set_size(&tunnel_hdr, length + INT_H_SIZE);
2330 outbuf = tipc_buf_acquire(length + INT_H_SIZE);
2331 if (outbuf == NULL) {
2332 warn("Link changeover error, "
2333 "unable to send duplicate msg\n");
2334 return;
2335 }
2336 skb_copy_to_linear_data(outbuf, &tunnel_hdr, INT_H_SIZE);
2337 skb_copy_to_linear_data_offset(outbuf, INT_H_SIZE, iter->data,
2338 length);
2339 tipc_link_send_buf(tunnel, outbuf);
2340 if (!tipc_link_is_up(l_ptr))
2341 return;
2342 iter = iter->next;
2343 }
2344 }
2345
2346
2347
2348 /**
2349 * buf_extract - extracts embedded TIPC message from another message
2350 * @skb: encapsulating message buffer
2351 * @from_pos: offset to extract from
2352 *
2353 * Returns a new message buffer containing an embedded message. The
2354 * encapsulating message itself is left unchanged.
2355 */
2356
buf_extract(struct sk_buff * skb,u32 from_pos)2357 static struct sk_buff *buf_extract(struct sk_buff *skb, u32 from_pos)
2358 {
2359 struct tipc_msg *msg = (struct tipc_msg *)(skb->data + from_pos);
2360 u32 size = msg_size(msg);
2361 struct sk_buff *eb;
2362
2363 eb = tipc_buf_acquire(size);
2364 if (eb)
2365 skb_copy_to_linear_data(eb, msg, size);
2366 return eb;
2367 }
2368
2369 /*
2370 * link_recv_changeover_msg(): Receive tunneled packet sent
2371 * via other link. Node is locked. Return extracted buffer.
2372 */
2373
link_recv_changeover_msg(struct tipc_link ** l_ptr,struct sk_buff ** buf)2374 static int link_recv_changeover_msg(struct tipc_link **l_ptr,
2375 struct sk_buff **buf)
2376 {
2377 struct sk_buff *tunnel_buf = *buf;
2378 struct tipc_link *dest_link;
2379 struct tipc_msg *msg;
2380 struct tipc_msg *tunnel_msg = buf_msg(tunnel_buf);
2381 u32 msg_typ = msg_type(tunnel_msg);
2382 u32 msg_count = msg_msgcnt(tunnel_msg);
2383
2384 dest_link = (*l_ptr)->owner->links[msg_bearer_id(tunnel_msg)];
2385 if (!dest_link)
2386 goto exit;
2387 if (dest_link == *l_ptr) {
2388 err("Unexpected changeover message on link <%s>\n",
2389 (*l_ptr)->name);
2390 goto exit;
2391 }
2392 *l_ptr = dest_link;
2393 msg = msg_get_wrapped(tunnel_msg);
2394
2395 if (msg_typ == DUPLICATE_MSG) {
2396 if (less(msg_seqno(msg), mod(dest_link->next_in_no)))
2397 goto exit;
2398 *buf = buf_extract(tunnel_buf, INT_H_SIZE);
2399 if (*buf == NULL) {
2400 warn("Link changeover error, duplicate msg dropped\n");
2401 goto exit;
2402 }
2403 kfree_skb(tunnel_buf);
2404 return 1;
2405 }
2406
2407 /* First original message ?: */
2408
2409 if (tipc_link_is_up(dest_link)) {
2410 info("Resetting link <%s>, changeover initiated by peer\n",
2411 dest_link->name);
2412 tipc_link_reset(dest_link);
2413 dest_link->exp_msg_count = msg_count;
2414 if (!msg_count)
2415 goto exit;
2416 } else if (dest_link->exp_msg_count == START_CHANGEOVER) {
2417 dest_link->exp_msg_count = msg_count;
2418 if (!msg_count)
2419 goto exit;
2420 }
2421
2422 /* Receive original message */
2423
2424 if (dest_link->exp_msg_count == 0) {
2425 warn("Link switchover error, "
2426 "got too many tunnelled messages\n");
2427 goto exit;
2428 }
2429 dest_link->exp_msg_count--;
2430 if (less(msg_seqno(msg), dest_link->reset_checkpoint)) {
2431 goto exit;
2432 } else {
2433 *buf = buf_extract(tunnel_buf, INT_H_SIZE);
2434 if (*buf != NULL) {
2435 kfree_skb(tunnel_buf);
2436 return 1;
2437 } else {
2438 warn("Link changeover error, original msg dropped\n");
2439 }
2440 }
2441 exit:
2442 *buf = NULL;
2443 kfree_skb(tunnel_buf);
2444 return 0;
2445 }
2446
2447 /*
2448 * Bundler functionality:
2449 */
tipc_link_recv_bundle(struct sk_buff * buf)2450 void tipc_link_recv_bundle(struct sk_buff *buf)
2451 {
2452 u32 msgcount = msg_msgcnt(buf_msg(buf));
2453 u32 pos = INT_H_SIZE;
2454 struct sk_buff *obuf;
2455
2456 while (msgcount--) {
2457 obuf = buf_extract(buf, pos);
2458 if (obuf == NULL) {
2459 warn("Link unable to unbundle message(s)\n");
2460 break;
2461 }
2462 pos += align(msg_size(buf_msg(obuf)));
2463 tipc_net_route_msg(obuf);
2464 }
2465 kfree_skb(buf);
2466 }
2467
2468 /*
2469 * Fragmentation/defragmentation:
2470 */
2471
2472
2473 /*
2474 * link_send_long_buf: Entry for buffers needing fragmentation.
2475 * The buffer is complete, inclusive total message length.
2476 * Returns user data length.
2477 */
link_send_long_buf(struct tipc_link * l_ptr,struct sk_buff * buf)2478 static int link_send_long_buf(struct tipc_link *l_ptr, struct sk_buff *buf)
2479 {
2480 struct sk_buff *buf_chain = NULL;
2481 struct sk_buff *buf_chain_tail = (struct sk_buff *)&buf_chain;
2482 struct tipc_msg *inmsg = buf_msg(buf);
2483 struct tipc_msg fragm_hdr;
2484 u32 insize = msg_size(inmsg);
2485 u32 dsz = msg_data_sz(inmsg);
2486 unchar *crs = buf->data;
2487 u32 rest = insize;
2488 u32 pack_sz = l_ptr->max_pkt;
2489 u32 fragm_sz = pack_sz - INT_H_SIZE;
2490 u32 fragm_no = 0;
2491 u32 destaddr;
2492
2493 if (msg_short(inmsg))
2494 destaddr = l_ptr->addr;
2495 else
2496 destaddr = msg_destnode(inmsg);
2497
2498 /* Prepare reusable fragment header: */
2499
2500 tipc_msg_init(&fragm_hdr, MSG_FRAGMENTER, FIRST_FRAGMENT,
2501 INT_H_SIZE, destaddr);
2502
2503 /* Chop up message: */
2504
2505 while (rest > 0) {
2506 struct sk_buff *fragm;
2507
2508 if (rest <= fragm_sz) {
2509 fragm_sz = rest;
2510 msg_set_type(&fragm_hdr, LAST_FRAGMENT);
2511 }
2512 fragm = tipc_buf_acquire(fragm_sz + INT_H_SIZE);
2513 if (fragm == NULL) {
2514 kfree_skb(buf);
2515 while (buf_chain) {
2516 buf = buf_chain;
2517 buf_chain = buf_chain->next;
2518 kfree_skb(buf);
2519 }
2520 return -ENOMEM;
2521 }
2522 msg_set_size(&fragm_hdr, fragm_sz + INT_H_SIZE);
2523 fragm_no++;
2524 msg_set_fragm_no(&fragm_hdr, fragm_no);
2525 skb_copy_to_linear_data(fragm, &fragm_hdr, INT_H_SIZE);
2526 skb_copy_to_linear_data_offset(fragm, INT_H_SIZE, crs,
2527 fragm_sz);
2528 buf_chain_tail->next = fragm;
2529 buf_chain_tail = fragm;
2530
2531 rest -= fragm_sz;
2532 crs += fragm_sz;
2533 msg_set_type(&fragm_hdr, FRAGMENT);
2534 }
2535 kfree_skb(buf);
2536
2537 /* Append chain of fragments to send queue & send them */
2538
2539 l_ptr->long_msg_seq_no++;
2540 link_add_chain_to_outqueue(l_ptr, buf_chain, l_ptr->long_msg_seq_no);
2541 l_ptr->stats.sent_fragments += fragm_no;
2542 l_ptr->stats.sent_fragmented++;
2543 tipc_link_push_queue(l_ptr);
2544
2545 return dsz;
2546 }
2547
2548 /*
2549 * A pending message being re-assembled must store certain values
2550 * to handle subsequent fragments correctly. The following functions
2551 * help storing these values in unused, available fields in the
2552 * pending message. This makes dynamic memory allocation unnecessary.
2553 */
2554
set_long_msg_seqno(struct sk_buff * buf,u32 seqno)2555 static void set_long_msg_seqno(struct sk_buff *buf, u32 seqno)
2556 {
2557 msg_set_seqno(buf_msg(buf), seqno);
2558 }
2559
get_fragm_size(struct sk_buff * buf)2560 static u32 get_fragm_size(struct sk_buff *buf)
2561 {
2562 return msg_ack(buf_msg(buf));
2563 }
2564
set_fragm_size(struct sk_buff * buf,u32 sz)2565 static void set_fragm_size(struct sk_buff *buf, u32 sz)
2566 {
2567 msg_set_ack(buf_msg(buf), sz);
2568 }
2569
get_expected_frags(struct sk_buff * buf)2570 static u32 get_expected_frags(struct sk_buff *buf)
2571 {
2572 return msg_bcast_ack(buf_msg(buf));
2573 }
2574
set_expected_frags(struct sk_buff * buf,u32 exp)2575 static void set_expected_frags(struct sk_buff *buf, u32 exp)
2576 {
2577 msg_set_bcast_ack(buf_msg(buf), exp);
2578 }
2579
get_timer_cnt(struct sk_buff * buf)2580 static u32 get_timer_cnt(struct sk_buff *buf)
2581 {
2582 return msg_reroute_cnt(buf_msg(buf));
2583 }
2584
incr_timer_cnt(struct sk_buff * buf)2585 static void incr_timer_cnt(struct sk_buff *buf)
2586 {
2587 msg_incr_reroute_cnt(buf_msg(buf));
2588 }
2589
2590 /*
2591 * tipc_link_recv_fragment(): Called with node lock on. Returns
2592 * the reassembled buffer if message is complete.
2593 */
tipc_link_recv_fragment(struct sk_buff ** pending,struct sk_buff ** fb,struct tipc_msg ** m)2594 int tipc_link_recv_fragment(struct sk_buff **pending, struct sk_buff **fb,
2595 struct tipc_msg **m)
2596 {
2597 struct sk_buff *prev = NULL;
2598 struct sk_buff *fbuf = *fb;
2599 struct tipc_msg *fragm = buf_msg(fbuf);
2600 struct sk_buff *pbuf = *pending;
2601 u32 long_msg_seq_no = msg_long_msgno(fragm);
2602
2603 *fb = NULL;
2604
2605 /* Is there an incomplete message waiting for this fragment? */
2606
2607 while (pbuf && ((buf_seqno(pbuf) != long_msg_seq_no) ||
2608 (msg_orignode(fragm) != msg_orignode(buf_msg(pbuf))))) {
2609 prev = pbuf;
2610 pbuf = pbuf->next;
2611 }
2612
2613 if (!pbuf && (msg_type(fragm) == FIRST_FRAGMENT)) {
2614 struct tipc_msg *imsg = (struct tipc_msg *)msg_data(fragm);
2615 u32 msg_sz = msg_size(imsg);
2616 u32 fragm_sz = msg_data_sz(fragm);
2617 u32 exp_fragm_cnt = msg_sz/fragm_sz + !!(msg_sz % fragm_sz);
2618 u32 max = TIPC_MAX_USER_MSG_SIZE + NAMED_H_SIZE;
2619 if (msg_type(imsg) == TIPC_MCAST_MSG)
2620 max = TIPC_MAX_USER_MSG_SIZE + MCAST_H_SIZE;
2621 if (msg_size(imsg) > max) {
2622 kfree_skb(fbuf);
2623 return 0;
2624 }
2625 pbuf = tipc_buf_acquire(msg_size(imsg));
2626 if (pbuf != NULL) {
2627 pbuf->next = *pending;
2628 *pending = pbuf;
2629 skb_copy_to_linear_data(pbuf, imsg,
2630 msg_data_sz(fragm));
2631 /* Prepare buffer for subsequent fragments. */
2632
2633 set_long_msg_seqno(pbuf, long_msg_seq_no);
2634 set_fragm_size(pbuf, fragm_sz);
2635 set_expected_frags(pbuf, exp_fragm_cnt - 1);
2636 } else {
2637 dbg("Link unable to reassemble fragmented message\n");
2638 kfree_skb(fbuf);
2639 return -1;
2640 }
2641 kfree_skb(fbuf);
2642 return 0;
2643 } else if (pbuf && (msg_type(fragm) != FIRST_FRAGMENT)) {
2644 u32 dsz = msg_data_sz(fragm);
2645 u32 fsz = get_fragm_size(pbuf);
2646 u32 crs = ((msg_fragm_no(fragm) - 1) * fsz);
2647 u32 exp_frags = get_expected_frags(pbuf) - 1;
2648 skb_copy_to_linear_data_offset(pbuf, crs,
2649 msg_data(fragm), dsz);
2650 kfree_skb(fbuf);
2651
2652 /* Is message complete? */
2653
2654 if (exp_frags == 0) {
2655 if (prev)
2656 prev->next = pbuf->next;
2657 else
2658 *pending = pbuf->next;
2659 msg_reset_reroute_cnt(buf_msg(pbuf));
2660 *fb = pbuf;
2661 *m = buf_msg(pbuf);
2662 return 1;
2663 }
2664 set_expected_frags(pbuf, exp_frags);
2665 return 0;
2666 }
2667 kfree_skb(fbuf);
2668 return 0;
2669 }
2670
2671 /**
2672 * link_check_defragm_bufs - flush stale incoming message fragments
2673 * @l_ptr: pointer to link
2674 */
2675
link_check_defragm_bufs(struct tipc_link * l_ptr)2676 static void link_check_defragm_bufs(struct tipc_link *l_ptr)
2677 {
2678 struct sk_buff *prev = NULL;
2679 struct sk_buff *next = NULL;
2680 struct sk_buff *buf = l_ptr->defragm_buf;
2681
2682 if (!buf)
2683 return;
2684 if (!link_working_working(l_ptr))
2685 return;
2686 while (buf) {
2687 u32 cnt = get_timer_cnt(buf);
2688
2689 next = buf->next;
2690 if (cnt < 4) {
2691 incr_timer_cnt(buf);
2692 prev = buf;
2693 } else {
2694 if (prev)
2695 prev->next = buf->next;
2696 else
2697 l_ptr->defragm_buf = buf->next;
2698 kfree_skb(buf);
2699 }
2700 buf = next;
2701 }
2702 }
2703
2704
2705
link_set_supervision_props(struct tipc_link * l_ptr,u32 tolerance)2706 static void link_set_supervision_props(struct tipc_link *l_ptr, u32 tolerance)
2707 {
2708 if ((tolerance < TIPC_MIN_LINK_TOL) || (tolerance > TIPC_MAX_LINK_TOL))
2709 return;
2710
2711 l_ptr->tolerance = tolerance;
2712 l_ptr->continuity_interval =
2713 ((tolerance / 4) > 500) ? 500 : tolerance / 4;
2714 l_ptr->abort_limit = tolerance / (l_ptr->continuity_interval / 4);
2715 }
2716
2717
tipc_link_set_queue_limits(struct tipc_link * l_ptr,u32 window)2718 void tipc_link_set_queue_limits(struct tipc_link *l_ptr, u32 window)
2719 {
2720 /* Data messages from this node, inclusive FIRST_FRAGM */
2721 l_ptr->queue_limit[TIPC_LOW_IMPORTANCE] = window;
2722 l_ptr->queue_limit[TIPC_MEDIUM_IMPORTANCE] = (window / 3) * 4;
2723 l_ptr->queue_limit[TIPC_HIGH_IMPORTANCE] = (window / 3) * 5;
2724 l_ptr->queue_limit[TIPC_CRITICAL_IMPORTANCE] = (window / 3) * 6;
2725 /* Transiting data messages,inclusive FIRST_FRAGM */
2726 l_ptr->queue_limit[TIPC_LOW_IMPORTANCE + 4] = 300;
2727 l_ptr->queue_limit[TIPC_MEDIUM_IMPORTANCE + 4] = 600;
2728 l_ptr->queue_limit[TIPC_HIGH_IMPORTANCE + 4] = 900;
2729 l_ptr->queue_limit[TIPC_CRITICAL_IMPORTANCE + 4] = 1200;
2730 l_ptr->queue_limit[CONN_MANAGER] = 1200;
2731 l_ptr->queue_limit[CHANGEOVER_PROTOCOL] = 2500;
2732 l_ptr->queue_limit[NAME_DISTRIBUTOR] = 3000;
2733 /* FRAGMENT and LAST_FRAGMENT packets */
2734 l_ptr->queue_limit[MSG_FRAGMENTER] = 4000;
2735 }
2736
2737 /**
2738 * link_find_link - locate link by name
2739 * @name - ptr to link name string
2740 * @node - ptr to area to be filled with ptr to associated node
2741 *
2742 * Caller must hold 'tipc_net_lock' to ensure node and bearer are not deleted;
2743 * this also prevents link deletion.
2744 *
2745 * Returns pointer to link (or 0 if invalid link name).
2746 */
2747
link_find_link(const char * name,struct tipc_node ** node)2748 static struct tipc_link *link_find_link(const char *name,
2749 struct tipc_node **node)
2750 {
2751 struct tipc_link_name link_name_parts;
2752 struct tipc_bearer *b_ptr;
2753 struct tipc_link *l_ptr;
2754
2755 if (!link_name_validate(name, &link_name_parts))
2756 return NULL;
2757
2758 b_ptr = tipc_bearer_find_interface(link_name_parts.if_local);
2759 if (!b_ptr)
2760 return NULL;
2761
2762 *node = tipc_node_find(link_name_parts.addr_peer);
2763 if (!*node)
2764 return NULL;
2765
2766 l_ptr = (*node)->links[b_ptr->identity];
2767 if (!l_ptr || strcmp(l_ptr->name, name))
2768 return NULL;
2769
2770 return l_ptr;
2771 }
2772
2773 /**
2774 * link_value_is_valid -- validate proposed link tolerance/priority/window
2775 *
2776 * @cmd - value type (TIPC_CMD_SET_LINK_*)
2777 * @new_value - the new value
2778 *
2779 * Returns 1 if value is within range, 0 if not.
2780 */
2781
link_value_is_valid(u16 cmd,u32 new_value)2782 static int link_value_is_valid(u16 cmd, u32 new_value)
2783 {
2784 switch (cmd) {
2785 case TIPC_CMD_SET_LINK_TOL:
2786 return (new_value >= TIPC_MIN_LINK_TOL) &&
2787 (new_value <= TIPC_MAX_LINK_TOL);
2788 case TIPC_CMD_SET_LINK_PRI:
2789 return (new_value <= TIPC_MAX_LINK_PRI);
2790 case TIPC_CMD_SET_LINK_WINDOW:
2791 return (new_value >= TIPC_MIN_LINK_WIN) &&
2792 (new_value <= TIPC_MAX_LINK_WIN);
2793 }
2794 return 0;
2795 }
2796
2797
2798 /**
2799 * link_cmd_set_value - change priority/tolerance/window for link/bearer/media
2800 * @name - ptr to link, bearer, or media name
2801 * @new_value - new value of link, bearer, or media setting
2802 * @cmd - which link, bearer, or media attribute to set (TIPC_CMD_SET_LINK_*)
2803 *
2804 * Caller must hold 'tipc_net_lock' to ensure link/bearer/media is not deleted.
2805 *
2806 * Returns 0 if value updated and negative value on error.
2807 */
2808
link_cmd_set_value(const char * name,u32 new_value,u16 cmd)2809 static int link_cmd_set_value(const char *name, u32 new_value, u16 cmd)
2810 {
2811 struct tipc_node *node;
2812 struct tipc_link *l_ptr;
2813 struct tipc_bearer *b_ptr;
2814 struct tipc_media *m_ptr;
2815
2816 l_ptr = link_find_link(name, &node);
2817 if (l_ptr) {
2818 /*
2819 * acquire node lock for tipc_link_send_proto_msg().
2820 * see "TIPC locking policy" in net.c.
2821 */
2822 tipc_node_lock(node);
2823 switch (cmd) {
2824 case TIPC_CMD_SET_LINK_TOL:
2825 link_set_supervision_props(l_ptr, new_value);
2826 tipc_link_send_proto_msg(l_ptr,
2827 STATE_MSG, 0, 0, new_value, 0, 0);
2828 break;
2829 case TIPC_CMD_SET_LINK_PRI:
2830 l_ptr->priority = new_value;
2831 tipc_link_send_proto_msg(l_ptr,
2832 STATE_MSG, 0, 0, 0, new_value, 0);
2833 break;
2834 case TIPC_CMD_SET_LINK_WINDOW:
2835 tipc_link_set_queue_limits(l_ptr, new_value);
2836 break;
2837 }
2838 tipc_node_unlock(node);
2839 return 0;
2840 }
2841
2842 b_ptr = tipc_bearer_find(name);
2843 if (b_ptr) {
2844 switch (cmd) {
2845 case TIPC_CMD_SET_LINK_TOL:
2846 b_ptr->tolerance = new_value;
2847 return 0;
2848 case TIPC_CMD_SET_LINK_PRI:
2849 b_ptr->priority = new_value;
2850 return 0;
2851 case TIPC_CMD_SET_LINK_WINDOW:
2852 b_ptr->window = new_value;
2853 return 0;
2854 }
2855 return -EINVAL;
2856 }
2857
2858 m_ptr = tipc_media_find(name);
2859 if (!m_ptr)
2860 return -ENODEV;
2861 switch (cmd) {
2862 case TIPC_CMD_SET_LINK_TOL:
2863 m_ptr->tolerance = new_value;
2864 return 0;
2865 case TIPC_CMD_SET_LINK_PRI:
2866 m_ptr->priority = new_value;
2867 return 0;
2868 case TIPC_CMD_SET_LINK_WINDOW:
2869 m_ptr->window = new_value;
2870 return 0;
2871 }
2872 return -EINVAL;
2873 }
2874
tipc_link_cmd_config(const void * req_tlv_area,int req_tlv_space,u16 cmd)2875 struct sk_buff *tipc_link_cmd_config(const void *req_tlv_area, int req_tlv_space,
2876 u16 cmd)
2877 {
2878 struct tipc_link_config *args;
2879 u32 new_value;
2880 int res;
2881
2882 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_CONFIG))
2883 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
2884
2885 args = (struct tipc_link_config *)TLV_DATA(req_tlv_area);
2886 new_value = ntohl(args->value);
2887
2888 if (!link_value_is_valid(cmd, new_value))
2889 return tipc_cfg_reply_error_string(
2890 "cannot change, value invalid");
2891
2892 if (!strcmp(args->name, tipc_bclink_name)) {
2893 if ((cmd == TIPC_CMD_SET_LINK_WINDOW) &&
2894 (tipc_bclink_set_queue_limits(new_value) == 0))
2895 return tipc_cfg_reply_none();
2896 return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED
2897 " (cannot change setting on broadcast link)");
2898 }
2899
2900 read_lock_bh(&tipc_net_lock);
2901 res = link_cmd_set_value(args->name, new_value, cmd);
2902 read_unlock_bh(&tipc_net_lock);
2903 if (res)
2904 return tipc_cfg_reply_error_string("cannot change link setting");
2905
2906 return tipc_cfg_reply_none();
2907 }
2908
2909 /**
2910 * link_reset_statistics - reset link statistics
2911 * @l_ptr: pointer to link
2912 */
2913
link_reset_statistics(struct tipc_link * l_ptr)2914 static void link_reset_statistics(struct tipc_link *l_ptr)
2915 {
2916 memset(&l_ptr->stats, 0, sizeof(l_ptr->stats));
2917 l_ptr->stats.sent_info = l_ptr->next_out_no;
2918 l_ptr->stats.recv_info = l_ptr->next_in_no;
2919 }
2920
tipc_link_cmd_reset_stats(const void * req_tlv_area,int req_tlv_space)2921 struct sk_buff *tipc_link_cmd_reset_stats(const void *req_tlv_area, int req_tlv_space)
2922 {
2923 char *link_name;
2924 struct tipc_link *l_ptr;
2925 struct tipc_node *node;
2926
2927 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_NAME))
2928 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
2929
2930 link_name = (char *)TLV_DATA(req_tlv_area);
2931 if (!strcmp(link_name, tipc_bclink_name)) {
2932 if (tipc_bclink_reset_stats())
2933 return tipc_cfg_reply_error_string("link not found");
2934 return tipc_cfg_reply_none();
2935 }
2936
2937 read_lock_bh(&tipc_net_lock);
2938 l_ptr = link_find_link(link_name, &node);
2939 if (!l_ptr) {
2940 read_unlock_bh(&tipc_net_lock);
2941 return tipc_cfg_reply_error_string("link not found");
2942 }
2943
2944 tipc_node_lock(node);
2945 link_reset_statistics(l_ptr);
2946 tipc_node_unlock(node);
2947 read_unlock_bh(&tipc_net_lock);
2948 return tipc_cfg_reply_none();
2949 }
2950
2951 /**
2952 * percent - convert count to a percentage of total (rounding up or down)
2953 */
2954
percent(u32 count,u32 total)2955 static u32 percent(u32 count, u32 total)
2956 {
2957 return (count * 100 + (total / 2)) / total;
2958 }
2959
2960 /**
2961 * tipc_link_stats - print link statistics
2962 * @name: link name
2963 * @buf: print buffer area
2964 * @buf_size: size of print buffer area
2965 *
2966 * Returns length of print buffer data string (or 0 if error)
2967 */
2968
tipc_link_stats(const char * name,char * buf,const u32 buf_size)2969 static int tipc_link_stats(const char *name, char *buf, const u32 buf_size)
2970 {
2971 struct print_buf pb;
2972 struct tipc_link *l_ptr;
2973 struct tipc_node *node;
2974 char *status;
2975 u32 profile_total = 0;
2976
2977 if (!strcmp(name, tipc_bclink_name))
2978 return tipc_bclink_stats(buf, buf_size);
2979
2980 tipc_printbuf_init(&pb, buf, buf_size);
2981
2982 read_lock_bh(&tipc_net_lock);
2983 l_ptr = link_find_link(name, &node);
2984 if (!l_ptr) {
2985 read_unlock_bh(&tipc_net_lock);
2986 return 0;
2987 }
2988 tipc_node_lock(node);
2989
2990 if (tipc_link_is_active(l_ptr))
2991 status = "ACTIVE";
2992 else if (tipc_link_is_up(l_ptr))
2993 status = "STANDBY";
2994 else
2995 status = "DEFUNCT";
2996 tipc_printf(&pb, "Link <%s>\n"
2997 " %s MTU:%u Priority:%u Tolerance:%u ms"
2998 " Window:%u packets\n",
2999 l_ptr->name, status, l_ptr->max_pkt,
3000 l_ptr->priority, l_ptr->tolerance, l_ptr->queue_limit[0]);
3001 tipc_printf(&pb, " RX packets:%u fragments:%u/%u bundles:%u/%u\n",
3002 l_ptr->next_in_no - l_ptr->stats.recv_info,
3003 l_ptr->stats.recv_fragments,
3004 l_ptr->stats.recv_fragmented,
3005 l_ptr->stats.recv_bundles,
3006 l_ptr->stats.recv_bundled);
3007 tipc_printf(&pb, " TX packets:%u fragments:%u/%u bundles:%u/%u\n",
3008 l_ptr->next_out_no - l_ptr->stats.sent_info,
3009 l_ptr->stats.sent_fragments,
3010 l_ptr->stats.sent_fragmented,
3011 l_ptr->stats.sent_bundles,
3012 l_ptr->stats.sent_bundled);
3013 profile_total = l_ptr->stats.msg_length_counts;
3014 if (!profile_total)
3015 profile_total = 1;
3016 tipc_printf(&pb, " TX profile sample:%u packets average:%u octets\n"
3017 " 0-64:%u%% -256:%u%% -1024:%u%% -4096:%u%% "
3018 "-16384:%u%% -32768:%u%% -66000:%u%%\n",
3019 l_ptr->stats.msg_length_counts,
3020 l_ptr->stats.msg_lengths_total / profile_total,
3021 percent(l_ptr->stats.msg_length_profile[0], profile_total),
3022 percent(l_ptr->stats.msg_length_profile[1], profile_total),
3023 percent(l_ptr->stats.msg_length_profile[2], profile_total),
3024 percent(l_ptr->stats.msg_length_profile[3], profile_total),
3025 percent(l_ptr->stats.msg_length_profile[4], profile_total),
3026 percent(l_ptr->stats.msg_length_profile[5], profile_total),
3027 percent(l_ptr->stats.msg_length_profile[6], profile_total));
3028 tipc_printf(&pb, " RX states:%u probes:%u naks:%u defs:%u dups:%u\n",
3029 l_ptr->stats.recv_states,
3030 l_ptr->stats.recv_probes,
3031 l_ptr->stats.recv_nacks,
3032 l_ptr->stats.deferred_recv,
3033 l_ptr->stats.duplicates);
3034 tipc_printf(&pb, " TX states:%u probes:%u naks:%u acks:%u dups:%u\n",
3035 l_ptr->stats.sent_states,
3036 l_ptr->stats.sent_probes,
3037 l_ptr->stats.sent_nacks,
3038 l_ptr->stats.sent_acks,
3039 l_ptr->stats.retransmitted);
3040 tipc_printf(&pb, " Congestion bearer:%u link:%u Send queue max:%u avg:%u\n",
3041 l_ptr->stats.bearer_congs,
3042 l_ptr->stats.link_congs,
3043 l_ptr->stats.max_queue_sz,
3044 l_ptr->stats.queue_sz_counts
3045 ? (l_ptr->stats.accu_queue_sz / l_ptr->stats.queue_sz_counts)
3046 : 0);
3047
3048 tipc_node_unlock(node);
3049 read_unlock_bh(&tipc_net_lock);
3050 return tipc_printbuf_validate(&pb);
3051 }
3052
3053 #define MAX_LINK_STATS_INFO 2000
3054
tipc_link_cmd_show_stats(const void * req_tlv_area,int req_tlv_space)3055 struct sk_buff *tipc_link_cmd_show_stats(const void *req_tlv_area, int req_tlv_space)
3056 {
3057 struct sk_buff *buf;
3058 struct tlv_desc *rep_tlv;
3059 int str_len;
3060
3061 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_NAME))
3062 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
3063
3064 buf = tipc_cfg_reply_alloc(TLV_SPACE(MAX_LINK_STATS_INFO));
3065 if (!buf)
3066 return NULL;
3067
3068 rep_tlv = (struct tlv_desc *)buf->data;
3069
3070 str_len = tipc_link_stats((char *)TLV_DATA(req_tlv_area),
3071 (char *)TLV_DATA(rep_tlv), MAX_LINK_STATS_INFO);
3072 if (!str_len) {
3073 kfree_skb(buf);
3074 return tipc_cfg_reply_error_string("link not found");
3075 }
3076
3077 skb_put(buf, TLV_SPACE(str_len));
3078 TLV_SET(rep_tlv, TIPC_TLV_ULTRA_STRING, NULL, str_len);
3079
3080 return buf;
3081 }
3082
3083 /**
3084 * tipc_link_get_max_pkt - get maximum packet size to use when sending to destination
3085 * @dest: network address of destination node
3086 * @selector: used to select from set of active links
3087 *
3088 * If no active link can be found, uses default maximum packet size.
3089 */
3090
tipc_link_get_max_pkt(u32 dest,u32 selector)3091 u32 tipc_link_get_max_pkt(u32 dest, u32 selector)
3092 {
3093 struct tipc_node *n_ptr;
3094 struct tipc_link *l_ptr;
3095 u32 res = MAX_PKT_DEFAULT;
3096
3097 if (dest == tipc_own_addr)
3098 return MAX_MSG_SIZE;
3099
3100 read_lock_bh(&tipc_net_lock);
3101 n_ptr = tipc_node_find(dest);
3102 if (n_ptr) {
3103 tipc_node_lock(n_ptr);
3104 l_ptr = n_ptr->active_links[selector & 1];
3105 if (l_ptr)
3106 res = l_ptr->max_pkt;
3107 tipc_node_unlock(n_ptr);
3108 }
3109 read_unlock_bh(&tipc_net_lock);
3110 return res;
3111 }
3112
link_print(struct tipc_link * l_ptr,const char * str)3113 static void link_print(struct tipc_link *l_ptr, const char *str)
3114 {
3115 char print_area[256];
3116 struct print_buf pb;
3117 struct print_buf *buf = &pb;
3118
3119 tipc_printbuf_init(buf, print_area, sizeof(print_area));
3120
3121 tipc_printf(buf, str);
3122 tipc_printf(buf, "Link %x<%s>:",
3123 l_ptr->addr, l_ptr->b_ptr->name);
3124
3125 #ifdef CONFIG_TIPC_DEBUG
3126 if (link_reset_reset(l_ptr) || link_reset_unknown(l_ptr))
3127 goto print_state;
3128
3129 tipc_printf(buf, ": NXO(%u):", mod(l_ptr->next_out_no));
3130 tipc_printf(buf, "NXI(%u):", mod(l_ptr->next_in_no));
3131 tipc_printf(buf, "SQUE");
3132 if (l_ptr->first_out) {
3133 tipc_printf(buf, "[%u..", buf_seqno(l_ptr->first_out));
3134 if (l_ptr->next_out)
3135 tipc_printf(buf, "%u..", buf_seqno(l_ptr->next_out));
3136 tipc_printf(buf, "%u]", buf_seqno(l_ptr->last_out));
3137 if ((mod(buf_seqno(l_ptr->last_out) -
3138 buf_seqno(l_ptr->first_out))
3139 != (l_ptr->out_queue_size - 1)) ||
3140 (l_ptr->last_out->next != NULL)) {
3141 tipc_printf(buf, "\nSend queue inconsistency\n");
3142 tipc_printf(buf, "first_out= %p ", l_ptr->first_out);
3143 tipc_printf(buf, "next_out= %p ", l_ptr->next_out);
3144 tipc_printf(buf, "last_out= %p ", l_ptr->last_out);
3145 }
3146 } else
3147 tipc_printf(buf, "[]");
3148 tipc_printf(buf, "SQSIZ(%u)", l_ptr->out_queue_size);
3149 if (l_ptr->oldest_deferred_in) {
3150 u32 o = buf_seqno(l_ptr->oldest_deferred_in);
3151 u32 n = buf_seqno(l_ptr->newest_deferred_in);
3152 tipc_printf(buf, ":RQUE[%u..%u]", o, n);
3153 if (l_ptr->deferred_inqueue_sz != mod((n + 1) - o)) {
3154 tipc_printf(buf, ":RQSIZ(%u)",
3155 l_ptr->deferred_inqueue_sz);
3156 }
3157 }
3158 print_state:
3159 #endif
3160
3161 if (link_working_unknown(l_ptr))
3162 tipc_printf(buf, ":WU");
3163 else if (link_reset_reset(l_ptr))
3164 tipc_printf(buf, ":RR");
3165 else if (link_reset_unknown(l_ptr))
3166 tipc_printf(buf, ":RU");
3167 else if (link_working_working(l_ptr))
3168 tipc_printf(buf, ":WW");
3169 tipc_printf(buf, "\n");
3170
3171 tipc_printbuf_validate(buf);
3172 info("%s", print_area);
3173 }
3174
3175