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tipc: let broadcast transmission use new link transmit function
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1/*
2 * net/tipc/link.c: TIPC link code
3 *
4 * Copyright (c) 1996-2007, 2012-2015, Ericsson AB
5 * Copyright (c) 2004-2007, 2010-2013, Wind River Systems
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the names of the copyright holders nor the names of its
17 * contributors may be used to endorse or promote products derived from
18 * this software without specific prior written permission.
19 *
20 * Alternatively, this software may be distributed under the terms of the
21 * GNU General Public License ("GPL") version 2 as published by the Free
22 * Software Foundation.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34 * POSSIBILITY OF SUCH DAMAGE.
35 */
36
37#include "core.h"
38#include "subscr.h"
39#include "link.h"
40#include "bcast.h"
41#include "socket.h"
42#include "name_distr.h"
43#include "discover.h"
44#include "netlink.h"
45
46#include <linux/pkt_sched.h>
47
48/*
49 * Error message prefixes
50 */
51static const char *link_co_err = "Link tunneling error, ";
52static const char *link_rst_msg = "Resetting link ";
53static const char tipc_bclink_name[] = "broadcast-link";
54
55static const struct nla_policy tipc_nl_link_policy[TIPC_NLA_LINK_MAX + 1] = {
56 [TIPC_NLA_LINK_UNSPEC] = { .type = NLA_UNSPEC },
57 [TIPC_NLA_LINK_NAME] = {
58 .type = NLA_STRING,
59 .len = TIPC_MAX_LINK_NAME
60 },
61 [TIPC_NLA_LINK_MTU] = { .type = NLA_U32 },
62 [TIPC_NLA_LINK_BROADCAST] = { .type = NLA_FLAG },
63 [TIPC_NLA_LINK_UP] = { .type = NLA_FLAG },
64 [TIPC_NLA_LINK_ACTIVE] = { .type = NLA_FLAG },
65 [TIPC_NLA_LINK_PROP] = { .type = NLA_NESTED },
66 [TIPC_NLA_LINK_STATS] = { .type = NLA_NESTED },
67 [TIPC_NLA_LINK_RX] = { .type = NLA_U32 },
68 [TIPC_NLA_LINK_TX] = { .type = NLA_U32 }
69};
70
71/* Properties valid for media, bearar and link */
72static const struct nla_policy tipc_nl_prop_policy[TIPC_NLA_PROP_MAX + 1] = {
73 [TIPC_NLA_PROP_UNSPEC] = { .type = NLA_UNSPEC },
74 [TIPC_NLA_PROP_PRIO] = { .type = NLA_U32 },
75 [TIPC_NLA_PROP_TOL] = { .type = NLA_U32 },
76 [TIPC_NLA_PROP_WIN] = { .type = NLA_U32 }
77};
78
79/*
80 * Interval between NACKs when packets arrive out of order
81 */
82#define TIPC_NACK_INTV (TIPC_MIN_LINK_WIN * 2)
83/*
84 * Out-of-range value for link session numbers
85 */
86#define WILDCARD_SESSION 0x10000
87
88/* Link FSM states:
89 */
90enum {
91 LINK_ESTABLISHED = 0xe,
92 LINK_ESTABLISHING = 0xe << 4,
93 LINK_RESET = 0x1 << 8,
94 LINK_RESETTING = 0x2 << 12,
95 LINK_PEER_RESET = 0xd << 16,
96 LINK_FAILINGOVER = 0xf << 20,
97 LINK_SYNCHING = 0xc << 24
98};
99
100/* Link FSM state checking routines
101 */
102static int link_is_up(struct tipc_link *l)
103{
104 return l->state & (LINK_ESTABLISHED | LINK_SYNCHING);
105}
106
107static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
108 struct sk_buff_head *xmitq);
109static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
110 u16 rcvgap, int tolerance, int priority,
111 struct sk_buff_head *xmitq);
112static void link_reset_statistics(struct tipc_link *l_ptr);
113static void link_print(struct tipc_link *l_ptr, const char *str);
114static void tipc_link_sync_rcv(struct tipc_node *n, struct sk_buff *buf);
115
116/*
117 * Simple non-static link routines (i.e. referenced outside this file)
118 */
119bool tipc_link_is_up(struct tipc_link *l)
120{
121 return link_is_up(l);
122}
123
124bool tipc_link_peer_is_down(struct tipc_link *l)
125{
126 return l->state == LINK_PEER_RESET;
127}
128
129bool tipc_link_is_reset(struct tipc_link *l)
130{
131 return l->state & (LINK_RESET | LINK_FAILINGOVER | LINK_ESTABLISHING);
132}
133
134bool tipc_link_is_establishing(struct tipc_link *l)
135{
136 return l->state == LINK_ESTABLISHING;
137}
138
139bool tipc_link_is_synching(struct tipc_link *l)
140{
141 return l->state == LINK_SYNCHING;
142}
143
144bool tipc_link_is_failingover(struct tipc_link *l)
145{
146 return l->state == LINK_FAILINGOVER;
147}
148
149bool tipc_link_is_blocked(struct tipc_link *l)
150{
151 return l->state & (LINK_RESETTING | LINK_PEER_RESET | LINK_FAILINGOVER);
152}
153
154int tipc_link_is_active(struct tipc_link *l)
155{
156 struct tipc_node *n = l->owner;
157
158 return (node_active_link(n, 0) == l) || (node_active_link(n, 1) == l);
159}
160
161void tipc_link_add_bc_peer(struct tipc_link *l)
162{
163 l->ackers++;
164}
165
166void tipc_link_remove_bc_peer(struct tipc_link *l)
167{
168 l->ackers--;
169}
170
171int tipc_link_bc_peers(struct tipc_link *l)
172{
173 return l->ackers;
174}
175
176static u32 link_own_addr(struct tipc_link *l)
177{
178 return msg_prevnode(l->pmsg);
179}
180
181/**
182 * tipc_link_create - create a new link
183 * @n: pointer to associated node
184 * @if_name: associated interface name
185 * @bearer_id: id (index) of associated bearer
186 * @tolerance: link tolerance to be used by link
187 * @net_plane: network plane (A,B,c..) this link belongs to
188 * @mtu: mtu to be advertised by link
189 * @priority: priority to be used by link
190 * @window: send window to be used by link
191 * @session: session to be used by link
192 * @ownnode: identity of own node
193 * @peer: node id of peer node
194 * @maddr: media address to be used
195 * @inputq: queue to put messages ready for delivery
196 * @namedq: queue to put binding table update messages ready for delivery
197 * @link: return value, pointer to put the created link
198 *
199 * Returns true if link was created, otherwise false
200 */
201bool tipc_link_create(struct tipc_node *n, char *if_name, int bearer_id,
202 int tolerance, char net_plane, u32 mtu, int priority,
203 int window, u32 session, u32 ownnode, u32 peer,
204 struct tipc_media_addr *maddr,
205 struct sk_buff_head *inputq, struct sk_buff_head *namedq,
206 struct tipc_link **link)
207{
208 struct tipc_link *l;
209 struct tipc_msg *hdr;
210
211 l = kzalloc(sizeof(*l), GFP_ATOMIC);
212 if (!l)
213 return false;
214 *link = l;
215 l->pmsg = (struct tipc_msg *)&l->proto_msg;
216 hdr = l->pmsg;
217 tipc_msg_init(ownnode, hdr, LINK_PROTOCOL, RESET_MSG, INT_H_SIZE, peer);
218 msg_set_size(hdr, sizeof(l->proto_msg));
219 msg_set_session(hdr, session);
220 msg_set_bearer_id(hdr, l->bearer_id);
221
222 /* Note: peer i/f name is completed by reset/activate message */
223 sprintf(l->name, "%u.%u.%u:%s-%u.%u.%u:unknown",
224 tipc_zone(ownnode), tipc_cluster(ownnode), tipc_node(ownnode),
225 if_name, tipc_zone(peer), tipc_cluster(peer), tipc_node(peer));
226 strcpy((char *)msg_data(hdr), if_name);
227
228 l->addr = peer;
229 l->media_addr = maddr;
230 l->owner = n;
231 l->peer_session = WILDCARD_SESSION;
232 l->bearer_id = bearer_id;
233 l->tolerance = tolerance;
234 l->net_plane = net_plane;
235 l->advertised_mtu = mtu;
236 l->mtu = mtu;
237 l->priority = priority;
238 tipc_link_set_queue_limits(l, window);
239 l->ackers = 1;
240 l->inputq = inputq;
241 l->namedq = namedq;
242 l->state = LINK_RESETTING;
243 __skb_queue_head_init(&l->transmq);
244 __skb_queue_head_init(&l->backlogq);
245 __skb_queue_head_init(&l->deferdq);
246 skb_queue_head_init(&l->wakeupq);
247 skb_queue_head_init(l->inputq);
248 return true;
249}
250
251/**
252 * tipc_link_bc_create - create new link to be used for broadcast
253 * @n: pointer to associated node
254 * @mtu: mtu to be used
255 * @window: send window to be used
256 * @inputq: queue to put messages ready for delivery
257 * @namedq: queue to put binding table update messages ready for delivery
258 * @link: return value, pointer to put the created link
259 *
260 * Returns true if link was created, otherwise false
261 */
262bool tipc_link_bc_create(struct tipc_node *n, int mtu, int window,
263 struct sk_buff_head *inputq,
264 struct sk_buff_head *namedq,
265 struct tipc_link **link)
266{
267 struct tipc_link *l;
268
269 if (!tipc_link_create(n, "", MAX_BEARERS, 0, 'Z', mtu, 0, window,
270 0, 0, 0, NULL, inputq, namedq, link))
271 return false;
272
273 l = *link;
274 strcpy(l->name, tipc_bclink_name);
275 tipc_link_reset(l);
276 l->ackers = 0;
277 return true;
278}
279
280/* tipc_link_build_bcast_sync_msg() - synchronize broadcast link endpoints.
281 *
282 * Give a newly added peer node the sequence number where it should
283 * start receiving and acking broadcast packets.
284 */
285void tipc_link_build_bcast_sync_msg(struct tipc_link *l,
286 struct sk_buff_head *xmitq)
287{
288 struct sk_buff *skb;
289 struct sk_buff_head list;
290 u16 last_sent;
291
292 skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE,
293 0, l->addr, link_own_addr(l), 0, 0, 0);
294 if (!skb)
295 return;
296 last_sent = tipc_bclink_get_last_sent(l->owner->net);
297 msg_set_last_bcast(buf_msg(skb), last_sent);
298 __skb_queue_head_init(&list);
299 __skb_queue_tail(&list, skb);
300 tipc_link_xmit(l, &list, xmitq);
301}
302
303/**
304 * tipc_link_fsm_evt - link finite state machine
305 * @l: pointer to link
306 * @evt: state machine event to be processed
307 */
308int tipc_link_fsm_evt(struct tipc_link *l, int evt)
309{
310 int rc = 0;
311
312 switch (l->state) {
313 case LINK_RESETTING:
314 switch (evt) {
315 case LINK_PEER_RESET_EVT:
316 l->state = LINK_PEER_RESET;
317 break;
318 case LINK_RESET_EVT:
319 l->state = LINK_RESET;
320 break;
321 case LINK_FAILURE_EVT:
322 case LINK_FAILOVER_BEGIN_EVT:
323 case LINK_ESTABLISH_EVT:
324 case LINK_FAILOVER_END_EVT:
325 case LINK_SYNCH_BEGIN_EVT:
326 case LINK_SYNCH_END_EVT:
327 default:
328 goto illegal_evt;
329 }
330 break;
331 case LINK_RESET:
332 switch (evt) {
333 case LINK_PEER_RESET_EVT:
334 l->state = LINK_ESTABLISHING;
335 break;
336 case LINK_FAILOVER_BEGIN_EVT:
337 l->state = LINK_FAILINGOVER;
338 case LINK_FAILURE_EVT:
339 case LINK_RESET_EVT:
340 case LINK_ESTABLISH_EVT:
341 case LINK_FAILOVER_END_EVT:
342 break;
343 case LINK_SYNCH_BEGIN_EVT:
344 case LINK_SYNCH_END_EVT:
345 default:
346 goto illegal_evt;
347 }
348 break;
349 case LINK_PEER_RESET:
350 switch (evt) {
351 case LINK_RESET_EVT:
352 l->state = LINK_ESTABLISHING;
353 break;
354 case LINK_PEER_RESET_EVT:
355 case LINK_ESTABLISH_EVT:
356 case LINK_FAILURE_EVT:
357 break;
358 case LINK_SYNCH_BEGIN_EVT:
359 case LINK_SYNCH_END_EVT:
360 case LINK_FAILOVER_BEGIN_EVT:
361 case LINK_FAILOVER_END_EVT:
362 default:
363 goto illegal_evt;
364 }
365 break;
366 case LINK_FAILINGOVER:
367 switch (evt) {
368 case LINK_FAILOVER_END_EVT:
369 l->state = LINK_RESET;
370 break;
371 case LINK_PEER_RESET_EVT:
372 case LINK_RESET_EVT:
373 case LINK_ESTABLISH_EVT:
374 case LINK_FAILURE_EVT:
375 break;
376 case LINK_FAILOVER_BEGIN_EVT:
377 case LINK_SYNCH_BEGIN_EVT:
378 case LINK_SYNCH_END_EVT:
379 default:
380 goto illegal_evt;
381 }
382 break;
383 case LINK_ESTABLISHING:
384 switch (evt) {
385 case LINK_ESTABLISH_EVT:
386 l->state = LINK_ESTABLISHED;
387 break;
388 case LINK_FAILOVER_BEGIN_EVT:
389 l->state = LINK_FAILINGOVER;
390 break;
391 case LINK_RESET_EVT:
392 l->state = LINK_RESET;
393 break;
394 case LINK_FAILURE_EVT:
395 case LINK_PEER_RESET_EVT:
396 case LINK_SYNCH_BEGIN_EVT:
397 case LINK_FAILOVER_END_EVT:
398 break;
399 case LINK_SYNCH_END_EVT:
400 default:
401 goto illegal_evt;
402 }
403 break;
404 case LINK_ESTABLISHED:
405 switch (evt) {
406 case LINK_PEER_RESET_EVT:
407 l->state = LINK_PEER_RESET;
408 rc |= TIPC_LINK_DOWN_EVT;
409 break;
410 case LINK_FAILURE_EVT:
411 l->state = LINK_RESETTING;
412 rc |= TIPC_LINK_DOWN_EVT;
413 break;
414 case LINK_RESET_EVT:
415 l->state = LINK_RESET;
416 break;
417 case LINK_ESTABLISH_EVT:
418 case LINK_SYNCH_END_EVT:
419 break;
420 case LINK_SYNCH_BEGIN_EVT:
421 l->state = LINK_SYNCHING;
422 break;
423 case LINK_FAILOVER_BEGIN_EVT:
424 case LINK_FAILOVER_END_EVT:
425 default:
426 goto illegal_evt;
427 }
428 break;
429 case LINK_SYNCHING:
430 switch (evt) {
431 case LINK_PEER_RESET_EVT:
432 l->state = LINK_PEER_RESET;
433 rc |= TIPC_LINK_DOWN_EVT;
434 break;
435 case LINK_FAILURE_EVT:
436 l->state = LINK_RESETTING;
437 rc |= TIPC_LINK_DOWN_EVT;
438 break;
439 case LINK_RESET_EVT:
440 l->state = LINK_RESET;
441 break;
442 case LINK_ESTABLISH_EVT:
443 case LINK_SYNCH_BEGIN_EVT:
444 break;
445 case LINK_SYNCH_END_EVT:
446 l->state = LINK_ESTABLISHED;
447 break;
448 case LINK_FAILOVER_BEGIN_EVT:
449 case LINK_FAILOVER_END_EVT:
450 default:
451 goto illegal_evt;
452 }
453 break;
454 default:
455 pr_err("Unknown FSM state %x in %s\n", l->state, l->name);
456 }
457 return rc;
458illegal_evt:
459 pr_err("Illegal FSM event %x in state %x on link %s\n",
460 evt, l->state, l->name);
461 return rc;
462}
463
464/* link_profile_stats - update statistical profiling of traffic
465 */
466static void link_profile_stats(struct tipc_link *l)
467{
468 struct sk_buff *skb;
469 struct tipc_msg *msg;
470 int length;
471
472 /* Update counters used in statistical profiling of send traffic */
473 l->stats.accu_queue_sz += skb_queue_len(&l->transmq);
474 l->stats.queue_sz_counts++;
475
476 skb = skb_peek(&l->transmq);
477 if (!skb)
478 return;
479 msg = buf_msg(skb);
480 length = msg_size(msg);
481
482 if (msg_user(msg) == MSG_FRAGMENTER) {
483 if (msg_type(msg) != FIRST_FRAGMENT)
484 return;
485 length = msg_size(msg_get_wrapped(msg));
486 }
487 l->stats.msg_lengths_total += length;
488 l->stats.msg_length_counts++;
489 if (length <= 64)
490 l->stats.msg_length_profile[0]++;
491 else if (length <= 256)
492 l->stats.msg_length_profile[1]++;
493 else if (length <= 1024)
494 l->stats.msg_length_profile[2]++;
495 else if (length <= 4096)
496 l->stats.msg_length_profile[3]++;
497 else if (length <= 16384)
498 l->stats.msg_length_profile[4]++;
499 else if (length <= 32768)
500 l->stats.msg_length_profile[5]++;
501 else
502 l->stats.msg_length_profile[6]++;
503}
504
505/* tipc_link_timeout - perform periodic task as instructed from node timeout
506 */
507int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq)
508{
509 int rc = 0;
510 int mtyp = STATE_MSG;
511 bool xmit = false;
512 bool prb = false;
513
514 link_profile_stats(l);
515
516 switch (l->state) {
517 case LINK_ESTABLISHED:
518 case LINK_SYNCHING:
519 if (!l->silent_intv_cnt) {
520 if (tipc_bclink_acks_missing(l->owner))
521 xmit = true;
522 } else if (l->silent_intv_cnt <= l->abort_limit) {
523 xmit = true;
524 prb = true;
525 } else {
526 rc |= tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
527 }
528 l->silent_intv_cnt++;
529 break;
530 case LINK_RESET:
531 xmit = true;
532 mtyp = RESET_MSG;
533 break;
534 case LINK_ESTABLISHING:
535 xmit = true;
536 mtyp = ACTIVATE_MSG;
537 break;
538 case LINK_PEER_RESET:
539 case LINK_RESETTING:
540 case LINK_FAILINGOVER:
541 break;
542 default:
543 break;
544 }
545
546 if (xmit)
547 tipc_link_build_proto_msg(l, mtyp, prb, 0, 0, 0, xmitq);
548
549 return rc;
550}
551
552/**
553 * link_schedule_user - schedule a message sender for wakeup after congestion
554 * @link: congested link
555 * @list: message that was attempted sent
556 * Create pseudo msg to send back to user when congestion abates
557 * Does not consume buffer list
558 */
559static int link_schedule_user(struct tipc_link *link, struct sk_buff_head *list)
560{
561 struct tipc_msg *msg = buf_msg(skb_peek(list));
562 int imp = msg_importance(msg);
563 u32 oport = msg_origport(msg);
564 u32 addr = link_own_addr(link);
565 struct sk_buff *skb;
566
567 /* This really cannot happen... */
568 if (unlikely(imp > TIPC_CRITICAL_IMPORTANCE)) {
569 pr_warn("%s<%s>, send queue full", link_rst_msg, link->name);
570 return -ENOBUFS;
571 }
572 /* Non-blocking sender: */
573 if (TIPC_SKB_CB(skb_peek(list))->wakeup_pending)
574 return -ELINKCONG;
575
576 /* Create and schedule wakeup pseudo message */
577 skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0,
578 addr, addr, oport, 0, 0);
579 if (!skb)
580 return -ENOBUFS;
581 TIPC_SKB_CB(skb)->chain_sz = skb_queue_len(list);
582 TIPC_SKB_CB(skb)->chain_imp = imp;
583 skb_queue_tail(&link->wakeupq, skb);
584 link->stats.link_congs++;
585 return -ELINKCONG;
586}
587
588/**
589 * link_prepare_wakeup - prepare users for wakeup after congestion
590 * @link: congested link
591 * Move a number of waiting users, as permitted by available space in
592 * the send queue, from link wait queue to node wait queue for wakeup
593 */
594void link_prepare_wakeup(struct tipc_link *l)
595{
596 int pnd[TIPC_SYSTEM_IMPORTANCE + 1] = {0,};
597 int imp, lim;
598 struct sk_buff *skb, *tmp;
599
600 skb_queue_walk_safe(&l->wakeupq, skb, tmp) {
601 imp = TIPC_SKB_CB(skb)->chain_imp;
602 lim = l->window + l->backlog[imp].limit;
603 pnd[imp] += TIPC_SKB_CB(skb)->chain_sz;
604 if ((pnd[imp] + l->backlog[imp].len) >= lim)
605 break;
606 skb_unlink(skb, &l->wakeupq);
607 skb_queue_tail(l->inputq, skb);
608 }
609}
610
611/**
612 * tipc_link_reset_fragments - purge link's inbound message fragments queue
613 * @l_ptr: pointer to link
614 */
615void tipc_link_reset_fragments(struct tipc_link *l_ptr)
616{
617 kfree_skb(l_ptr->reasm_buf);
618 l_ptr->reasm_buf = NULL;
619}
620
621void tipc_link_purge_backlog(struct tipc_link *l)
622{
623 __skb_queue_purge(&l->backlogq);
624 l->backlog[TIPC_LOW_IMPORTANCE].len = 0;
625 l->backlog[TIPC_MEDIUM_IMPORTANCE].len = 0;
626 l->backlog[TIPC_HIGH_IMPORTANCE].len = 0;
627 l->backlog[TIPC_CRITICAL_IMPORTANCE].len = 0;
628 l->backlog[TIPC_SYSTEM_IMPORTANCE].len = 0;
629}
630
631/**
632 * tipc_link_purge_queues - purge all pkt queues associated with link
633 * @l_ptr: pointer to link
634 */
635void tipc_link_purge_queues(struct tipc_link *l_ptr)
636{
637 __skb_queue_purge(&l_ptr->deferdq);
638 __skb_queue_purge(&l_ptr->transmq);
639 tipc_link_purge_backlog(l_ptr);
640 tipc_link_reset_fragments(l_ptr);
641}
642
643void tipc_link_reset(struct tipc_link *l)
644{
645 /* Link is down, accept any session */
646 l->peer_session = WILDCARD_SESSION;
647
648 /* If peer is up, it only accepts an incremented session number */
649 msg_set_session(l->pmsg, msg_session(l->pmsg) + 1);
650
651 /* Prepare for renewed mtu size negotiation */
652 l->mtu = l->advertised_mtu;
653
654 /* Clean up all queues: */
655 __skb_queue_purge(&l->transmq);
656 __skb_queue_purge(&l->deferdq);
657 skb_queue_splice_init(&l->wakeupq, l->inputq);
658
659 tipc_link_purge_backlog(l);
660 kfree_skb(l->reasm_buf);
661 kfree_skb(l->failover_reasm_skb);
662 l->reasm_buf = NULL;
663 l->failover_reasm_skb = NULL;
664 l->rcv_unacked = 0;
665 l->snd_nxt = 1;
666 l->rcv_nxt = 1;
667 l->acked = 0;
668 l->silent_intv_cnt = 0;
669 l->stats.recv_info = 0;
670 l->stale_count = 0;
671 link_reset_statistics(l);
672}
673
674/**
675 * __tipc_link_xmit(): same as tipc_link_xmit, but destlink is known & locked
676 * @link: link to use
677 * @list: chain of buffers containing message
678 *
679 * Consumes the buffer chain, except when returning an error code,
680 * Returns 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS
681 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted
682 */
683int __tipc_link_xmit(struct net *net, struct tipc_link *link,
684 struct sk_buff_head *list)
685{
686 struct tipc_msg *msg = buf_msg(skb_peek(list));
687 unsigned int maxwin = link->window;
688 unsigned int i, imp = msg_importance(msg);
689 uint mtu = link->mtu;
690 u16 ack = mod(link->rcv_nxt - 1);
691 u16 seqno = link->snd_nxt;
692 u16 bc_last_in = link->owner->bclink.last_in;
693 struct tipc_media_addr *addr = link->media_addr;
694 struct sk_buff_head *transmq = &link->transmq;
695 struct sk_buff_head *backlogq = &link->backlogq;
696 struct sk_buff *skb, *bskb;
697
698 /* Match msg importance against this and all higher backlog limits: */
699 for (i = imp; i <= TIPC_SYSTEM_IMPORTANCE; i++) {
700 if (unlikely(link->backlog[i].len >= link->backlog[i].limit))
701 return link_schedule_user(link, list);
702 }
703 if (unlikely(msg_size(msg) > mtu))
704 return -EMSGSIZE;
705
706 /* Prepare each packet for sending, and add to relevant queue: */
707 while (skb_queue_len(list)) {
708 skb = skb_peek(list);
709 msg = buf_msg(skb);
710 msg_set_seqno(msg, seqno);
711 msg_set_ack(msg, ack);
712 msg_set_bcast_ack(msg, bc_last_in);
713
714 if (likely(skb_queue_len(transmq) < maxwin)) {
715 __skb_dequeue(list);
716 __skb_queue_tail(transmq, skb);
717 tipc_bearer_send(net, link->bearer_id, skb, addr);
718 link->rcv_unacked = 0;
719 seqno++;
720 continue;
721 }
722 if (tipc_msg_bundle(skb_peek_tail(backlogq), msg, mtu)) {
723 kfree_skb(__skb_dequeue(list));
724 link->stats.sent_bundled++;
725 continue;
726 }
727 if (tipc_msg_make_bundle(&bskb, msg, mtu, link->addr)) {
728 kfree_skb(__skb_dequeue(list));
729 __skb_queue_tail(backlogq, bskb);
730 link->backlog[msg_importance(buf_msg(bskb))].len++;
731 link->stats.sent_bundled++;
732 link->stats.sent_bundles++;
733 continue;
734 }
735 link->backlog[imp].len += skb_queue_len(list);
736 skb_queue_splice_tail_init(list, backlogq);
737 }
738 link->snd_nxt = seqno;
739 return 0;
740}
741
742/**
743 * tipc_link_xmit(): enqueue buffer list according to queue situation
744 * @link: link to use
745 * @list: chain of buffers containing message
746 * @xmitq: returned list of packets to be sent by caller
747 *
748 * Consumes the buffer chain, except when returning -ELINKCONG,
749 * since the caller then may want to make more send attempts.
750 * Returns 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS
751 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted
752 */
753int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list,
754 struct sk_buff_head *xmitq)
755{
756 struct tipc_msg *hdr = buf_msg(skb_peek(list));
757 unsigned int maxwin = l->window;
758 unsigned int i, imp = msg_importance(hdr);
759 unsigned int mtu = l->mtu;
760 u16 ack = l->rcv_nxt - 1;
761 u16 seqno = l->snd_nxt;
762 u16 bc_last_in = l->owner->bclink.last_in;
763 struct sk_buff_head *transmq = &l->transmq;
764 struct sk_buff_head *backlogq = &l->backlogq;
765 struct sk_buff *skb, *_skb, *bskb;
766
767 /* Match msg importance against this and all higher backlog limits: */
768 for (i = imp; i <= TIPC_SYSTEM_IMPORTANCE; i++) {
769 if (unlikely(l->backlog[i].len >= l->backlog[i].limit))
770 return link_schedule_user(l, list);
771 }
772 if (unlikely(msg_size(hdr) > mtu))
773 return -EMSGSIZE;
774
775 /* Prepare each packet for sending, and add to relevant queue: */
776 while (skb_queue_len(list)) {
777 skb = skb_peek(list);
778 hdr = buf_msg(skb);
779 msg_set_seqno(hdr, seqno);
780 msg_set_ack(hdr, ack);
781 msg_set_bcast_ack(hdr, bc_last_in);
782
783 if (likely(skb_queue_len(transmq) < maxwin)) {
784 _skb = skb_clone(skb, GFP_ATOMIC);
785 if (!_skb)
786 return -ENOBUFS;
787 __skb_dequeue(list);
788 __skb_queue_tail(transmq, skb);
789 __skb_queue_tail(xmitq, _skb);
790 TIPC_SKB_CB(skb)->ackers = l->ackers;
791 l->rcv_unacked = 0;
792 seqno++;
793 continue;
794 }
795 if (tipc_msg_bundle(skb_peek_tail(backlogq), hdr, mtu)) {
796 kfree_skb(__skb_dequeue(list));
797 l->stats.sent_bundled++;
798 continue;
799 }
800 if (tipc_msg_make_bundle(&bskb, hdr, mtu, l->addr)) {
801 kfree_skb(__skb_dequeue(list));
802 __skb_queue_tail(backlogq, bskb);
803 l->backlog[msg_importance(buf_msg(bskb))].len++;
804 l->stats.sent_bundled++;
805 l->stats.sent_bundles++;
806 continue;
807 }
808 l->backlog[imp].len += skb_queue_len(list);
809 skb_queue_splice_tail_init(list, backlogq);
810 }
811 l->snd_nxt = seqno;
812 return 0;
813}
814
815/*
816 * tipc_link_sync_rcv - synchronize broadcast link endpoints.
817 * Receive the sequence number where we should start receiving and
818 * acking broadcast packets from a newly added peer node, and open
819 * up for reception of such packets.
820 *
821 * Called with node locked
822 */
823static void tipc_link_sync_rcv(struct tipc_node *n, struct sk_buff *buf)
824{
825 struct tipc_msg *msg = buf_msg(buf);
826
827 n->bclink.last_sent = n->bclink.last_in = msg_last_bcast(msg);
828 n->bclink.recv_permitted = true;
829 kfree_skb(buf);
830}
831
832/*
833 * tipc_link_push_packets - push unsent packets to bearer
834 *
835 * Push out the unsent messages of a link where congestion
836 * has abated. Node is locked.
837 *
838 * Called with node locked
839 */
840void tipc_link_push_packets(struct tipc_link *link)
841{
842 struct sk_buff *skb;
843 struct tipc_msg *msg;
844 u16 seqno = link->snd_nxt;
845 u16 ack = mod(link->rcv_nxt - 1);
846
847 while (skb_queue_len(&link->transmq) < link->window) {
848 skb = __skb_dequeue(&link->backlogq);
849 if (!skb)
850 break;
851 TIPC_SKB_CB(skb)->ackers = link->ackers;
852 msg = buf_msg(skb);
853 link->backlog[msg_importance(msg)].len--;
854 msg_set_ack(msg, ack);
855 msg_set_seqno(msg, seqno);
856 seqno = mod(seqno + 1);
857 msg_set_bcast_ack(msg, link->owner->bclink.last_in);
858 link->rcv_unacked = 0;
859 __skb_queue_tail(&link->transmq, skb);
860 tipc_bearer_send(link->owner->net, link->bearer_id,
861 skb, link->media_addr);
862 }
863 link->snd_nxt = seqno;
864}
865
866void tipc_link_advance_backlog(struct tipc_link *l, struct sk_buff_head *xmitq)
867{
868 struct sk_buff *skb, *_skb;
869 struct tipc_msg *hdr;
870 u16 seqno = l->snd_nxt;
871 u16 ack = l->rcv_nxt - 1;
872
873 while (skb_queue_len(&l->transmq) < l->window) {
874 skb = skb_peek(&l->backlogq);
875 if (!skb)
876 break;
877 _skb = skb_clone(skb, GFP_ATOMIC);
878 if (!_skb)
879 break;
880 __skb_dequeue(&l->backlogq);
881 hdr = buf_msg(skb);
882 l->backlog[msg_importance(hdr)].len--;
883 __skb_queue_tail(&l->transmq, skb);
884 __skb_queue_tail(xmitq, _skb);
885 TIPC_SKB_CB(skb)->ackers = l->ackers;
886 msg_set_ack(hdr, ack);
887 msg_set_seqno(hdr, seqno);
888 msg_set_bcast_ack(hdr, l->owner->bclink.last_in);
889 l->rcv_unacked = 0;
890 seqno++;
891 }
892 l->snd_nxt = seqno;
893}
894
895static void link_retransmit_failure(struct tipc_link *l_ptr,
896 struct sk_buff *buf)
897{
898 struct tipc_msg *msg = buf_msg(buf);
899 struct net *net = l_ptr->owner->net;
900
901 pr_warn("Retransmission failure on link <%s>\n", l_ptr->name);
902
903 if (l_ptr->addr) {
904 /* Handle failure on standard link */
905 link_print(l_ptr, "Resetting link ");
906 pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n",
907 msg_user(msg), msg_type(msg), msg_size(msg),
908 msg_errcode(msg));
909 pr_info("sqno %u, prev: %x, src: %x\n",
910 msg_seqno(msg), msg_prevnode(msg), msg_orignode(msg));
911 } else {
912 /* Handle failure on broadcast link */
913 struct tipc_node *n_ptr;
914 char addr_string[16];
915
916 pr_info("Msg seq number: %u, ", msg_seqno(msg));
917 pr_cont("Outstanding acks: %u\n", TIPC_SKB_CB(buf)->ackers);
918
919 n_ptr = tipc_bclink_retransmit_to(net);
920
921 tipc_addr_string_fill(addr_string, n_ptr->addr);
922 pr_info("Broadcast link info for %s\n", addr_string);
923 pr_info("Reception permitted: %d, Acked: %u\n",
924 n_ptr->bclink.recv_permitted,
925 n_ptr->bclink.acked);
926 pr_info("Last in: %u, Oos state: %u, Last sent: %u\n",
927 n_ptr->bclink.last_in,
928 n_ptr->bclink.oos_state,
929 n_ptr->bclink.last_sent);
930
931 n_ptr->action_flags |= TIPC_BCAST_RESET;
932 l_ptr->stale_count = 0;
933 }
934}
935
936void tipc_link_retransmit(struct tipc_link *l_ptr, struct sk_buff *skb,
937 u32 retransmits)
938{
939 struct tipc_msg *msg;
940
941 if (!skb)
942 return;
943
944 msg = buf_msg(skb);
945
946 /* Detect repeated retransmit failures */
947 if (l_ptr->last_retransm == msg_seqno(msg)) {
948 if (++l_ptr->stale_count > 100) {
949 link_retransmit_failure(l_ptr, skb);
950 return;
951 }
952 } else {
953 l_ptr->last_retransm = msg_seqno(msg);
954 l_ptr->stale_count = 1;
955 }
956
957 skb_queue_walk_from(&l_ptr->transmq, skb) {
958 if (!retransmits)
959 break;
960 msg = buf_msg(skb);
961 msg_set_ack(msg, mod(l_ptr->rcv_nxt - 1));
962 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
963 tipc_bearer_send(l_ptr->owner->net, l_ptr->bearer_id, skb,
964 l_ptr->media_addr);
965 retransmits--;
966 l_ptr->stats.retransmitted++;
967 }
968}
969
970int tipc_link_retrans(struct tipc_link *l, u16 from, u16 to,
971 struct sk_buff_head *xmitq)
972{
973 struct sk_buff *_skb, *skb = skb_peek(&l->transmq);
974 struct tipc_msg *hdr;
975 u16 ack = l->rcv_nxt - 1;
976 u16 bc_ack = l->owner->bclink.last_in;
977
978 if (!skb)
979 return 0;
980
981 /* Detect repeated retransmit failures on same packet */
982 if (likely(l->last_retransm != buf_seqno(skb))) {
983 l->last_retransm = buf_seqno(skb);
984 l->stale_count = 1;
985 } else if (++l->stale_count > 100) {
986 link_retransmit_failure(l, skb);
987 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
988 }
989
990 /* Move forward to where retransmission should start */
991 skb_queue_walk(&l->transmq, skb) {
992 if (!less(buf_seqno(skb), from))
993 break;
994 }
995
996 skb_queue_walk_from(&l->transmq, skb) {
997 if (more(buf_seqno(skb), to))
998 break;
999 hdr = buf_msg(skb);
1000 _skb = __pskb_copy(skb, MIN_H_SIZE, GFP_ATOMIC);
1001 if (!_skb)
1002 return 0;
1003 hdr = buf_msg(_skb);
1004 msg_set_ack(hdr, ack);
1005 msg_set_bcast_ack(hdr, bc_ack);
1006 _skb->priority = TC_PRIO_CONTROL;
1007 __skb_queue_tail(xmitq, _skb);
1008 l->stats.retransmitted++;
1009 }
1010 return 0;
1011}
1012
1013/* tipc_data_input - deliver data and name distr msgs to upper layer
1014 *
1015 * Consumes buffer if message is of right type
1016 * Node lock must be held
1017 */
1018static bool tipc_data_input(struct tipc_link *link, struct sk_buff *skb,
1019 struct sk_buff_head *inputq)
1020{
1021 struct tipc_node *node = link->owner;
1022
1023 switch (msg_user(buf_msg(skb))) {
1024 case TIPC_LOW_IMPORTANCE:
1025 case TIPC_MEDIUM_IMPORTANCE:
1026 case TIPC_HIGH_IMPORTANCE:
1027 case TIPC_CRITICAL_IMPORTANCE:
1028 case CONN_MANAGER:
1029 skb_queue_tail(inputq, skb);
1030 return true;
1031 case NAME_DISTRIBUTOR:
1032 node->bclink.recv_permitted = true;
1033 skb_queue_tail(link->namedq, skb);
1034 return true;
1035 case MSG_BUNDLER:
1036 case TUNNEL_PROTOCOL:
1037 case MSG_FRAGMENTER:
1038 case BCAST_PROTOCOL:
1039 return false;
1040 default:
1041 pr_warn("Dropping received illegal msg type\n");
1042 kfree_skb(skb);
1043 return false;
1044 };
1045}
1046
1047/* tipc_link_input - process packet that has passed link protocol check
1048 *
1049 * Consumes buffer
1050 */
1051static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb,
1052 struct sk_buff_head *inputq)
1053{
1054 struct tipc_node *node = l->owner;
1055 struct tipc_msg *hdr = buf_msg(skb);
1056 struct sk_buff **reasm_skb = &l->reasm_buf;
1057 struct sk_buff *iskb;
1058 struct sk_buff_head tmpq;
1059 int usr = msg_user(hdr);
1060 int rc = 0;
1061 int pos = 0;
1062 int ipos = 0;
1063
1064 if (unlikely(usr == TUNNEL_PROTOCOL)) {
1065 if (msg_type(hdr) == SYNCH_MSG) {
1066 __skb_queue_purge(&l->deferdq);
1067 goto drop;
1068 }
1069 if (!tipc_msg_extract(skb, &iskb, &ipos))
1070 return rc;
1071 kfree_skb(skb);
1072 skb = iskb;
1073 hdr = buf_msg(skb);
1074 if (less(msg_seqno(hdr), l->drop_point))
1075 goto drop;
1076 if (tipc_data_input(l, skb, inputq))
1077 return rc;
1078 usr = msg_user(hdr);
1079 reasm_skb = &l->failover_reasm_skb;
1080 }
1081
1082 if (usr == MSG_BUNDLER) {
1083 skb_queue_head_init(&tmpq);
1084 l->stats.recv_bundles++;
1085 l->stats.recv_bundled += msg_msgcnt(hdr);
1086 while (tipc_msg_extract(skb, &iskb, &pos))
1087 tipc_data_input(l, iskb, &tmpq);
1088 tipc_skb_queue_splice_tail(&tmpq, inputq);
1089 return 0;
1090 } else if (usr == MSG_FRAGMENTER) {
1091 l->stats.recv_fragments++;
1092 if (tipc_buf_append(reasm_skb, &skb)) {
1093 l->stats.recv_fragmented++;
1094 tipc_data_input(l, skb, inputq);
1095 } else if (!*reasm_skb) {
1096 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1097 }
1098 return 0;
1099 } else if (usr == BCAST_PROTOCOL) {
1100 tipc_link_sync_rcv(node, skb);
1101 return 0;
1102 }
1103drop:
1104 kfree_skb(skb);
1105 return 0;
1106}
1107
1108static bool tipc_link_release_pkts(struct tipc_link *l, u16 acked)
1109{
1110 bool released = false;
1111 struct sk_buff *skb, *tmp;
1112
1113 skb_queue_walk_safe(&l->transmq, skb, tmp) {
1114 if (more(buf_seqno(skb), acked))
1115 break;
1116 __skb_unlink(skb, &l->transmq);
1117 kfree_skb(skb);
1118 released = true;
1119 }
1120 return released;
1121}
1122
1123/* tipc_link_build_ack_msg: prepare link acknowledge message for transmission
1124 */
1125void tipc_link_build_ack_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1126{
1127 l->rcv_unacked = 0;
1128 l->stats.sent_acks++;
1129 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, xmitq);
1130}
1131
1132/* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message
1133 */
1134void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1135{
1136 int mtyp = RESET_MSG;
1137
1138 if (l->state == LINK_ESTABLISHING)
1139 mtyp = ACTIVATE_MSG;
1140
1141 tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, xmitq);
1142}
1143
1144/* tipc_link_build_nack_msg: prepare link nack message for transmission
1145 */
1146static void tipc_link_build_nack_msg(struct tipc_link *l,
1147 struct sk_buff_head *xmitq)
1148{
1149 u32 def_cnt = ++l->stats.deferred_recv;
1150
1151 if ((skb_queue_len(&l->deferdq) == 1) || !(def_cnt % TIPC_NACK_INTV))
1152 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, xmitq);
1153}
1154
1155/* tipc_link_rcv - process TIPC packets/messages arriving from off-node
1156 * @l: the link that should handle the message
1157 * @skb: TIPC packet
1158 * @xmitq: queue to place packets to be sent after this call
1159 */
1160int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb,
1161 struct sk_buff_head *xmitq)
1162{
1163 struct sk_buff_head *defq = &l->deferdq;
1164 struct tipc_msg *hdr;
1165 u16 seqno, rcv_nxt, win_lim;
1166 int rc = 0;
1167
1168 do {
1169 hdr = buf_msg(skb);
1170 seqno = msg_seqno(hdr);
1171 rcv_nxt = l->rcv_nxt;
1172 win_lim = rcv_nxt + TIPC_MAX_LINK_WIN;
1173
1174 /* Verify and update link state */
1175 if (unlikely(msg_user(hdr) == LINK_PROTOCOL))
1176 return tipc_link_proto_rcv(l, skb, xmitq);
1177
1178 if (unlikely(!link_is_up(l))) {
1179 if (l->state == LINK_ESTABLISHING)
1180 rc = TIPC_LINK_UP_EVT;
1181 goto drop;
1182 }
1183
1184 /* Don't send probe at next timeout expiration */
1185 l->silent_intv_cnt = 0;
1186
1187 /* Drop if outside receive window */
1188 if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) {
1189 l->stats.duplicates++;
1190 goto drop;
1191 }
1192
1193 /* Forward queues and wake up waiting users */
1194 if (likely(tipc_link_release_pkts(l, msg_ack(hdr)))) {
1195 tipc_link_advance_backlog(l, xmitq);
1196 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1197 link_prepare_wakeup(l);
1198 }
1199
1200 /* Defer delivery if sequence gap */
1201 if (unlikely(seqno != rcv_nxt)) {
1202 __tipc_skb_queue_sorted(defq, seqno, skb);
1203 tipc_link_build_nack_msg(l, xmitq);
1204 break;
1205 }
1206
1207 /* Deliver packet */
1208 l->rcv_nxt++;
1209 l->stats.recv_info++;
1210 if (!tipc_data_input(l, skb, l->inputq))
1211 rc = tipc_link_input(l, skb, l->inputq);
1212 if (unlikely(rc))
1213 break;
1214 if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN))
1215 tipc_link_build_ack_msg(l, xmitq);
1216
1217 } while ((skb = __skb_dequeue(defq)));
1218
1219 return rc;
1220drop:
1221 kfree_skb(skb);
1222 return rc;
1223}
1224
1225/**
1226 * tipc_link_defer_pkt - Add out-of-sequence message to deferred reception queue
1227 *
1228 * Returns increase in queue length (i.e. 0 or 1)
1229 */
1230u32 tipc_link_defer_pkt(struct sk_buff_head *list, struct sk_buff *skb)
1231{
1232 struct sk_buff *skb1;
1233 u16 seq_no = buf_seqno(skb);
1234
1235 /* Empty queue ? */
1236 if (skb_queue_empty(list)) {
1237 __skb_queue_tail(list, skb);
1238 return 1;
1239 }
1240
1241 /* Last ? */
1242 if (less(buf_seqno(skb_peek_tail(list)), seq_no)) {
1243 __skb_queue_tail(list, skb);
1244 return 1;
1245 }
1246
1247 /* Locate insertion point in queue, then insert; discard if duplicate */
1248 skb_queue_walk(list, skb1) {
1249 u16 curr_seqno = buf_seqno(skb1);
1250
1251 if (seq_no == curr_seqno) {
1252 kfree_skb(skb);
1253 return 0;
1254 }
1255
1256 if (less(seq_no, curr_seqno))
1257 break;
1258 }
1259
1260 __skb_queue_before(list, skb1, skb);
1261 return 1;
1262}
1263
1264/*
1265 * Send protocol message to the other endpoint.
1266 */
1267void tipc_link_proto_xmit(struct tipc_link *l, u32 msg_typ, int probe_msg,
1268 u32 gap, u32 tolerance, u32 priority)
1269{
1270 struct sk_buff *skb = NULL;
1271 struct sk_buff_head xmitq;
1272
1273 __skb_queue_head_init(&xmitq);
1274 tipc_link_build_proto_msg(l, msg_typ, probe_msg, gap,
1275 tolerance, priority, &xmitq);
1276 skb = __skb_dequeue(&xmitq);
1277 if (!skb)
1278 return;
1279 tipc_bearer_send(l->owner->net, l->bearer_id, skb, l->media_addr);
1280 l->rcv_unacked = 0;
1281 kfree_skb(skb);
1282}
1283
1284/* tipc_link_build_proto_msg: prepare link protocol message for transmission
1285 */
1286static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
1287 u16 rcvgap, int tolerance, int priority,
1288 struct sk_buff_head *xmitq)
1289{
1290 struct sk_buff *skb = NULL;
1291 struct tipc_msg *hdr = l->pmsg;
1292 u16 snd_nxt = l->snd_nxt;
1293 u16 rcv_nxt = l->rcv_nxt;
1294 u16 rcv_last = rcv_nxt - 1;
1295 int node_up = l->owner->bclink.recv_permitted;
1296
1297 /* Don't send protocol message during reset or link failover */
1298 if (tipc_link_is_blocked(l))
1299 return;
1300
1301 msg_set_type(hdr, mtyp);
1302 msg_set_net_plane(hdr, l->net_plane);
1303 msg_set_bcast_ack(hdr, l->owner->bclink.last_in);
1304 msg_set_last_bcast(hdr, tipc_bclink_get_last_sent(l->owner->net));
1305 msg_set_link_tolerance(hdr, tolerance);
1306 msg_set_linkprio(hdr, priority);
1307 msg_set_redundant_link(hdr, node_up);
1308 msg_set_seq_gap(hdr, 0);
1309
1310 /* Compatibility: created msg must not be in sequence with pkt flow */
1311 msg_set_seqno(hdr, snd_nxt + U16_MAX / 2);
1312
1313 if (mtyp == STATE_MSG) {
1314 if (!tipc_link_is_up(l))
1315 return;
1316 msg_set_next_sent(hdr, snd_nxt);
1317
1318 /* Override rcvgap if there are packets in deferred queue */
1319 if (!skb_queue_empty(&l->deferdq))
1320 rcvgap = buf_seqno(skb_peek(&l->deferdq)) - rcv_nxt;
1321 if (rcvgap) {
1322 msg_set_seq_gap(hdr, rcvgap);
1323 l->stats.sent_nacks++;
1324 }
1325 msg_set_ack(hdr, rcv_last);
1326 msg_set_probe(hdr, probe);
1327 if (probe)
1328 l->stats.sent_probes++;
1329 l->stats.sent_states++;
1330 } else {
1331 /* RESET_MSG or ACTIVATE_MSG */
1332 msg_set_max_pkt(hdr, l->advertised_mtu);
1333 msg_set_ack(hdr, l->rcv_nxt - 1);
1334 msg_set_next_sent(hdr, 1);
1335 }
1336 skb = tipc_buf_acquire(msg_size(hdr));
1337 if (!skb)
1338 return;
1339 skb_copy_to_linear_data(skb, hdr, msg_size(hdr));
1340 skb->priority = TC_PRIO_CONTROL;
1341 __skb_queue_tail(xmitq, skb);
1342}
1343
1344/* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets
1345 * with contents of the link's transmit and backlog queues.
1346 */
1347void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
1348 int mtyp, struct sk_buff_head *xmitq)
1349{
1350 struct sk_buff *skb, *tnlskb;
1351 struct tipc_msg *hdr, tnlhdr;
1352 struct sk_buff_head *queue = &l->transmq;
1353 struct sk_buff_head tmpxq, tnlq;
1354 u16 pktlen, pktcnt, seqno = l->snd_nxt;
1355
1356 if (!tnl)
1357 return;
1358
1359 skb_queue_head_init(&tnlq);
1360 skb_queue_head_init(&tmpxq);
1361
1362 /* At least one packet required for safe algorithm => add dummy */
1363 skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1364 BASIC_H_SIZE, 0, l->addr, link_own_addr(l),
1365 0, 0, TIPC_ERR_NO_PORT);
1366 if (!skb) {
1367 pr_warn("%sunable to create tunnel packet\n", link_co_err);
1368 return;
1369 }
1370 skb_queue_tail(&tnlq, skb);
1371 tipc_link_xmit(l, &tnlq, &tmpxq);
1372 __skb_queue_purge(&tmpxq);
1373
1374 /* Initialize reusable tunnel packet header */
1375 tipc_msg_init(link_own_addr(l), &tnlhdr, TUNNEL_PROTOCOL,
1376 mtyp, INT_H_SIZE, l->addr);
1377 pktcnt = skb_queue_len(&l->transmq) + skb_queue_len(&l->backlogq);
1378 msg_set_msgcnt(&tnlhdr, pktcnt);
1379 msg_set_bearer_id(&tnlhdr, l->peer_bearer_id);
1380tnl:
1381 /* Wrap each packet into a tunnel packet */
1382 skb_queue_walk(queue, skb) {
1383 hdr = buf_msg(skb);
1384 if (queue == &l->backlogq)
1385 msg_set_seqno(hdr, seqno++);
1386 pktlen = msg_size(hdr);
1387 msg_set_size(&tnlhdr, pktlen + INT_H_SIZE);
1388 tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE);
1389 if (!tnlskb) {
1390 pr_warn("%sunable to send packet\n", link_co_err);
1391 return;
1392 }
1393 skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE);
1394 skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen);
1395 __skb_queue_tail(&tnlq, tnlskb);
1396 }
1397 if (queue != &l->backlogq) {
1398 queue = &l->backlogq;
1399 goto tnl;
1400 }
1401
1402 tipc_link_xmit(tnl, &tnlq, xmitq);
1403
1404 if (mtyp == FAILOVER_MSG) {
1405 tnl->drop_point = l->rcv_nxt;
1406 tnl->failover_reasm_skb = l->reasm_buf;
1407 l->reasm_buf = NULL;
1408 }
1409}
1410
1411/* tipc_link_proto_rcv(): receive link level protocol message :
1412 * Note that network plane id propagates through the network, and may
1413 * change at any time. The node with lowest numerical id determines
1414 * network plane
1415 */
1416static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
1417 struct sk_buff_head *xmitq)
1418{
1419 struct tipc_msg *hdr = buf_msg(skb);
1420 u16 rcvgap = 0;
1421 u16 ack = msg_ack(hdr);
1422 u16 gap = msg_seq_gap(hdr);
1423 u16 peers_snd_nxt = msg_next_sent(hdr);
1424 u16 peers_tol = msg_link_tolerance(hdr);
1425 u16 peers_prio = msg_linkprio(hdr);
1426 u16 rcv_nxt = l->rcv_nxt;
1427 int mtyp = msg_type(hdr);
1428 char *if_name;
1429 int rc = 0;
1430
1431 if (tipc_link_is_blocked(l))
1432 goto exit;
1433
1434 if (link_own_addr(l) > msg_prevnode(hdr))
1435 l->net_plane = msg_net_plane(hdr);
1436
1437 switch (mtyp) {
1438 case RESET_MSG:
1439
1440 /* Ignore duplicate RESET with old session number */
1441 if ((less_eq(msg_session(hdr), l->peer_session)) &&
1442 (l->peer_session != WILDCARD_SESSION))
1443 break;
1444 /* fall thru' */
1445
1446 case ACTIVATE_MSG:
1447
1448 /* Complete own link name with peer's interface name */
1449 if_name = strrchr(l->name, ':') + 1;
1450 if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME)
1451 break;
1452 if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME)
1453 break;
1454 strncpy(if_name, msg_data(hdr), TIPC_MAX_IF_NAME);
1455
1456 /* Update own tolerance if peer indicates a non-zero value */
1457 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL))
1458 l->tolerance = peers_tol;
1459
1460 /* Update own priority if peer's priority is higher */
1461 if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
1462 l->priority = peers_prio;
1463
1464 /* ACTIVATE_MSG serves as PEER_RESET if link is already down */
1465 if ((mtyp == RESET_MSG) || !link_is_up(l))
1466 rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT);
1467
1468 /* ACTIVATE_MSG takes up link if it was already locally reset */
1469 if ((mtyp == ACTIVATE_MSG) && (l->state == LINK_ESTABLISHING))
1470 rc = TIPC_LINK_UP_EVT;
1471
1472 l->peer_session = msg_session(hdr);
1473 l->peer_bearer_id = msg_bearer_id(hdr);
1474 if (l->mtu > msg_max_pkt(hdr))
1475 l->mtu = msg_max_pkt(hdr);
1476 break;
1477
1478 case STATE_MSG:
1479
1480 /* Update own tolerance if peer indicates a non-zero value */
1481 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL))
1482 l->tolerance = peers_tol;
1483
1484 l->silent_intv_cnt = 0;
1485 l->stats.recv_states++;
1486 if (msg_probe(hdr))
1487 l->stats.recv_probes++;
1488
1489 if (!link_is_up(l)) {
1490 if (l->state == LINK_ESTABLISHING)
1491 rc = TIPC_LINK_UP_EVT;
1492 break;
1493 }
1494
1495 /* Send NACK if peer has sent pkts we haven't received yet */
1496 if (more(peers_snd_nxt, rcv_nxt) && !tipc_link_is_synching(l))
1497 rcvgap = peers_snd_nxt - l->rcv_nxt;
1498 if (rcvgap || (msg_probe(hdr)))
1499 tipc_link_build_proto_msg(l, STATE_MSG, 0, rcvgap,
1500 0, 0, xmitq);
1501 tipc_link_release_pkts(l, ack);
1502
1503 /* If NACK, retransmit will now start at right position */
1504 if (gap) {
1505 rc = tipc_link_retrans(l, ack + 1, ack + gap, xmitq);
1506 l->stats.recv_nacks++;
1507 }
1508
1509 tipc_link_advance_backlog(l, xmitq);
1510 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1511 link_prepare_wakeup(l);
1512 }
1513exit:
1514 kfree_skb(skb);
1515 return rc;
1516}
1517
1518void tipc_link_set_queue_limits(struct tipc_link *l, u32 win)
1519{
1520 int max_bulk = TIPC_MAX_PUBLICATIONS / (l->mtu / ITEM_SIZE);
1521
1522 l->window = win;
1523 l->backlog[TIPC_LOW_IMPORTANCE].limit = win / 2;
1524 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = win;
1525 l->backlog[TIPC_HIGH_IMPORTANCE].limit = win / 2 * 3;
1526 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = win * 2;
1527 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk;
1528}
1529
1530/* tipc_link_find_owner - locate owner node of link by link's name
1531 * @net: the applicable net namespace
1532 * @name: pointer to link name string
1533 * @bearer_id: pointer to index in 'node->links' array where the link was found.
1534 *
1535 * Returns pointer to node owning the link, or 0 if no matching link is found.
1536 */
1537static struct tipc_node *tipc_link_find_owner(struct net *net,
1538 const char *link_name,
1539 unsigned int *bearer_id)
1540{
1541 struct tipc_net *tn = net_generic(net, tipc_net_id);
1542 struct tipc_link *l_ptr;
1543 struct tipc_node *n_ptr;
1544 struct tipc_node *found_node = NULL;
1545 int i;
1546
1547 *bearer_id = 0;
1548 rcu_read_lock();
1549 list_for_each_entry_rcu(n_ptr, &tn->node_list, list) {
1550 tipc_node_lock(n_ptr);
1551 for (i = 0; i < MAX_BEARERS; i++) {
1552 l_ptr = n_ptr->links[i].link;
1553 if (l_ptr && !strcmp(l_ptr->name, link_name)) {
1554 *bearer_id = i;
1555 found_node = n_ptr;
1556 break;
1557 }
1558 }
1559 tipc_node_unlock(n_ptr);
1560 if (found_node)
1561 break;
1562 }
1563 rcu_read_unlock();
1564
1565 return found_node;
1566}
1567
1568/**
1569 * link_reset_statistics - reset link statistics
1570 * @l_ptr: pointer to link
1571 */
1572static void link_reset_statistics(struct tipc_link *l_ptr)
1573{
1574 memset(&l_ptr->stats, 0, sizeof(l_ptr->stats));
1575 l_ptr->stats.sent_info = l_ptr->snd_nxt;
1576 l_ptr->stats.recv_info = l_ptr->rcv_nxt;
1577}
1578
1579static void link_print(struct tipc_link *l, const char *str)
1580{
1581 struct sk_buff *hskb = skb_peek(&l->transmq);
1582 u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1;
1583 u16 tail = l->snd_nxt - 1;
1584
1585 pr_info("%s Link <%s> state %x\n", str, l->name, l->state);
1586 pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n",
1587 skb_queue_len(&l->transmq), head, tail,
1588 skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt);
1589}
1590
1591/* Parse and validate nested (link) properties valid for media, bearer and link
1592 */
1593int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
1594{
1595 int err;
1596
1597 err = nla_parse_nested(props, TIPC_NLA_PROP_MAX, prop,
1598 tipc_nl_prop_policy);
1599 if (err)
1600 return err;
1601
1602 if (props[TIPC_NLA_PROP_PRIO]) {
1603 u32 prio;
1604
1605 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
1606 if (prio > TIPC_MAX_LINK_PRI)
1607 return -EINVAL;
1608 }
1609
1610 if (props[TIPC_NLA_PROP_TOL]) {
1611 u32 tol;
1612
1613 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
1614 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
1615 return -EINVAL;
1616 }
1617
1618 if (props[TIPC_NLA_PROP_WIN]) {
1619 u32 win;
1620
1621 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
1622 if ((win < TIPC_MIN_LINK_WIN) || (win > TIPC_MAX_LINK_WIN))
1623 return -EINVAL;
1624 }
1625
1626 return 0;
1627}
1628
1629int tipc_nl_link_set(struct sk_buff *skb, struct genl_info *info)
1630{
1631 int err;
1632 int res = 0;
1633 int bearer_id;
1634 char *name;
1635 struct tipc_link *link;
1636 struct tipc_node *node;
1637 struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
1638 struct net *net = sock_net(skb->sk);
1639
1640 if (!info->attrs[TIPC_NLA_LINK])
1641 return -EINVAL;
1642
1643 err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX,
1644 info->attrs[TIPC_NLA_LINK],
1645 tipc_nl_link_policy);
1646 if (err)
1647 return err;
1648
1649 if (!attrs[TIPC_NLA_LINK_NAME])
1650 return -EINVAL;
1651
1652 name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
1653
1654 if (strcmp(name, tipc_bclink_name) == 0)
1655 return tipc_nl_bc_link_set(net, attrs);
1656
1657 node = tipc_link_find_owner(net, name, &bearer_id);
1658 if (!node)
1659 return -EINVAL;
1660
1661 tipc_node_lock(node);
1662
1663 link = node->links[bearer_id].link;
1664 if (!link) {
1665 res = -EINVAL;
1666 goto out;
1667 }
1668
1669 if (attrs[TIPC_NLA_LINK_PROP]) {
1670 struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
1671
1672 err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP],
1673 props);
1674 if (err) {
1675 res = err;
1676 goto out;
1677 }
1678
1679 if (props[TIPC_NLA_PROP_TOL]) {
1680 u32 tol;
1681
1682 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
1683 link->tolerance = tol;
1684 tipc_link_proto_xmit(link, STATE_MSG, 0, 0, tol, 0);
1685 }
1686 if (props[TIPC_NLA_PROP_PRIO]) {
1687 u32 prio;
1688
1689 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
1690 link->priority = prio;
1691 tipc_link_proto_xmit(link, STATE_MSG, 0, 0, 0, prio);
1692 }
1693 if (props[TIPC_NLA_PROP_WIN]) {
1694 u32 win;
1695
1696 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
1697 tipc_link_set_queue_limits(link, win);
1698 }
1699 }
1700
1701out:
1702 tipc_node_unlock(node);
1703
1704 return res;
1705}
1706
1707static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
1708{
1709 int i;
1710 struct nlattr *stats;
1711
1712 struct nla_map {
1713 u32 key;
1714 u32 val;
1715 };
1716
1717 struct nla_map map[] = {
1718 {TIPC_NLA_STATS_RX_INFO, s->recv_info},
1719 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
1720 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
1721 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
1722 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
1723 {TIPC_NLA_STATS_TX_INFO, s->sent_info},
1724 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
1725 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
1726 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
1727 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
1728 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
1729 s->msg_length_counts : 1},
1730 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
1731 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
1732 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
1733 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
1734 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
1735 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
1736 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
1737 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
1738 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
1739 {TIPC_NLA_STATS_RX_STATES, s->recv_states},
1740 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
1741 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
1742 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
1743 {TIPC_NLA_STATS_TX_STATES, s->sent_states},
1744 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
1745 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
1746 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
1747 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
1748 {TIPC_NLA_STATS_DUPLICATES, s->duplicates},
1749 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
1750 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
1751 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
1752 (s->accu_queue_sz / s->queue_sz_counts) : 0}
1753 };
1754
1755 stats = nla_nest_start(skb, TIPC_NLA_LINK_STATS);
1756 if (!stats)
1757 return -EMSGSIZE;
1758
1759 for (i = 0; i < ARRAY_SIZE(map); i++)
1760 if (nla_put_u32(skb, map[i].key, map[i].val))
1761 goto msg_full;
1762
1763 nla_nest_end(skb, stats);
1764
1765 return 0;
1766msg_full:
1767 nla_nest_cancel(skb, stats);
1768
1769 return -EMSGSIZE;
1770}
1771
1772/* Caller should hold appropriate locks to protect the link */
1773static int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
1774 struct tipc_link *link, int nlflags)
1775{
1776 int err;
1777 void *hdr;
1778 struct nlattr *attrs;
1779 struct nlattr *prop;
1780 struct tipc_net *tn = net_generic(net, tipc_net_id);
1781
1782 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
1783 nlflags, TIPC_NL_LINK_GET);
1784 if (!hdr)
1785 return -EMSGSIZE;
1786
1787 attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK);
1788 if (!attrs)
1789 goto msg_full;
1790
1791 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
1792 goto attr_msg_full;
1793 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST,
1794 tipc_cluster_mask(tn->own_addr)))
1795 goto attr_msg_full;
1796 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu))
1797 goto attr_msg_full;
1798 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->rcv_nxt))
1799 goto attr_msg_full;
1800 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->snd_nxt))
1801 goto attr_msg_full;
1802
1803 if (tipc_link_is_up(link))
1804 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
1805 goto attr_msg_full;
1806 if (tipc_link_is_active(link))
1807 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
1808 goto attr_msg_full;
1809
1810 prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP);
1811 if (!prop)
1812 goto attr_msg_full;
1813 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
1814 goto prop_msg_full;
1815 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
1816 goto prop_msg_full;
1817 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
1818 link->window))
1819 goto prop_msg_full;
1820 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
1821 goto prop_msg_full;
1822 nla_nest_end(msg->skb, prop);
1823
1824 err = __tipc_nl_add_stats(msg->skb, &link->stats);
1825 if (err)
1826 goto attr_msg_full;
1827
1828 nla_nest_end(msg->skb, attrs);
1829 genlmsg_end(msg->skb, hdr);
1830
1831 return 0;
1832
1833prop_msg_full:
1834 nla_nest_cancel(msg->skb, prop);
1835attr_msg_full:
1836 nla_nest_cancel(msg->skb, attrs);
1837msg_full:
1838 genlmsg_cancel(msg->skb, hdr);
1839
1840 return -EMSGSIZE;
1841}
1842
1843/* Caller should hold node lock */
1844static int __tipc_nl_add_node_links(struct net *net, struct tipc_nl_msg *msg,
1845 struct tipc_node *node, u32 *prev_link)
1846{
1847 u32 i;
1848 int err;
1849
1850 for (i = *prev_link; i < MAX_BEARERS; i++) {
1851 *prev_link = i;
1852
1853 if (!node->links[i].link)
1854 continue;
1855
1856 err = __tipc_nl_add_link(net, msg,
1857 node->links[i].link, NLM_F_MULTI);
1858 if (err)
1859 return err;
1860 }
1861 *prev_link = 0;
1862
1863 return 0;
1864}
1865
1866int tipc_nl_link_dump(struct sk_buff *skb, struct netlink_callback *cb)
1867{
1868 struct net *net = sock_net(skb->sk);
1869 struct tipc_net *tn = net_generic(net, tipc_net_id);
1870 struct tipc_node *node;
1871 struct tipc_nl_msg msg;
1872 u32 prev_node = cb->args[0];
1873 u32 prev_link = cb->args[1];
1874 int done = cb->args[2];
1875 int err;
1876
1877 if (done)
1878 return 0;
1879
1880 msg.skb = skb;
1881 msg.portid = NETLINK_CB(cb->skb).portid;
1882 msg.seq = cb->nlh->nlmsg_seq;
1883
1884 rcu_read_lock();
1885 if (prev_node) {
1886 node = tipc_node_find(net, prev_node);
1887 if (!node) {
1888 /* We never set seq or call nl_dump_check_consistent()
1889 * this means that setting prev_seq here will cause the
1890 * consistence check to fail in the netlink callback
1891 * handler. Resulting in the last NLMSG_DONE message
1892 * having the NLM_F_DUMP_INTR flag set.
1893 */
1894 cb->prev_seq = 1;
1895 goto out;
1896 }
1897 tipc_node_put(node);
1898
1899 list_for_each_entry_continue_rcu(node, &tn->node_list,
1900 list) {
1901 tipc_node_lock(node);
1902 err = __tipc_nl_add_node_links(net, &msg, node,
1903 &prev_link);
1904 tipc_node_unlock(node);
1905 if (err)
1906 goto out;
1907
1908 prev_node = node->addr;
1909 }
1910 } else {
1911 err = tipc_nl_add_bc_link(net, &msg);
1912 if (err)
1913 goto out;
1914
1915 list_for_each_entry_rcu(node, &tn->node_list, list) {
1916 tipc_node_lock(node);
1917 err = __tipc_nl_add_node_links(net, &msg, node,
1918 &prev_link);
1919 tipc_node_unlock(node);
1920 if (err)
1921 goto out;
1922
1923 prev_node = node->addr;
1924 }
1925 }
1926 done = 1;
1927out:
1928 rcu_read_unlock();
1929
1930 cb->args[0] = prev_node;
1931 cb->args[1] = prev_link;
1932 cb->args[2] = done;
1933
1934 return skb->len;
1935}
1936
1937int tipc_nl_link_get(struct sk_buff *skb, struct genl_info *info)
1938{
1939 struct net *net = genl_info_net(info);
1940 struct tipc_nl_msg msg;
1941 char *name;
1942 int err;
1943
1944 msg.portid = info->snd_portid;
1945 msg.seq = info->snd_seq;
1946
1947 if (!info->attrs[TIPC_NLA_LINK_NAME])
1948 return -EINVAL;
1949 name = nla_data(info->attrs[TIPC_NLA_LINK_NAME]);
1950
1951 msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
1952 if (!msg.skb)
1953 return -ENOMEM;
1954
1955 if (strcmp(name, tipc_bclink_name) == 0) {
1956 err = tipc_nl_add_bc_link(net, &msg);
1957 if (err) {
1958 nlmsg_free(msg.skb);
1959 return err;
1960 }
1961 } else {
1962 int bearer_id;
1963 struct tipc_node *node;
1964 struct tipc_link *link;
1965
1966 node = tipc_link_find_owner(net, name, &bearer_id);
1967 if (!node)
1968 return -EINVAL;
1969
1970 tipc_node_lock(node);
1971 link = node->links[bearer_id].link;
1972 if (!link) {
1973 tipc_node_unlock(node);
1974 nlmsg_free(msg.skb);
1975 return -EINVAL;
1976 }
1977
1978 err = __tipc_nl_add_link(net, &msg, link, 0);
1979 tipc_node_unlock(node);
1980 if (err) {
1981 nlmsg_free(msg.skb);
1982 return err;
1983 }
1984 }
1985
1986 return genlmsg_reply(msg.skb, info);
1987}
1988
1989int tipc_nl_link_reset_stats(struct sk_buff *skb, struct genl_info *info)
1990{
1991 int err;
1992 char *link_name;
1993 unsigned int bearer_id;
1994 struct tipc_link *link;
1995 struct tipc_node *node;
1996 struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
1997 struct net *net = sock_net(skb->sk);
1998
1999 if (!info->attrs[TIPC_NLA_LINK])
2000 return -EINVAL;
2001
2002 err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX,
2003 info->attrs[TIPC_NLA_LINK],
2004 tipc_nl_link_policy);
2005 if (err)
2006 return err;
2007
2008 if (!attrs[TIPC_NLA_LINK_NAME])
2009 return -EINVAL;
2010
2011 link_name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2012
2013 if (strcmp(link_name, tipc_bclink_name) == 0) {
2014 err = tipc_bclink_reset_stats(net);
2015 if (err)
2016 return err;
2017 return 0;
2018 }
2019
2020 node = tipc_link_find_owner(net, link_name, &bearer_id);
2021 if (!node)
2022 return -EINVAL;
2023
2024 tipc_node_lock(node);
2025
2026 link = node->links[bearer_id].link;
2027 if (!link) {
2028 tipc_node_unlock(node);
2029 return -EINVAL;
2030 }
2031
2032 link_reset_statistics(link);
2033
2034 tipc_node_unlock(node);
2035
2036 return 0;
2037}
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