projects / deliverable / linux.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
tipc: narrow down exposure of struct tipc_node
[deliverable/linux.git] / net / tipc / link.c
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 */
51 static const char *link_co_err = "Link tunneling error, ";
52 static const char *link_rst_msg = "Resetting link ";
53
54 /* Properties valid for media, bearar and link */
55 static const struct nla_policy tipc_nl_prop_policy[TIPC_NLA_PROP_MAX + 1] = {
56 [TIPC_NLA_PROP_UNSPEC] = { .type = NLA_UNSPEC },
57 [TIPC_NLA_PROP_PRIO] = { .type = NLA_U32 },
58 [TIPC_NLA_PROP_TOL] = { .type = NLA_U32 },
59 [TIPC_NLA_PROP_WIN] = { .type = NLA_U32 }
60 };
61
62 /* Send states for broadcast NACKs
63 */
64 enum {
65 BC_NACK_SND_CONDITIONAL,
66 BC_NACK_SND_UNCONDITIONAL,
67 BC_NACK_SND_SUPPRESS,
68 };
69
70 /*
71 * Interval between NACKs when packets arrive out of order
72 */
73 #define TIPC_NACK_INTV (TIPC_MIN_LINK_WIN * 2)
74 /*
75 * Out-of-range value for link session numbers
76 */
77 #define WILDCARD_SESSION 0x10000
78
79 /* Link FSM states:
80 */
81 enum {
82 LINK_ESTABLISHED = 0xe,
83 LINK_ESTABLISHING = 0xe << 4,
84 LINK_RESET = 0x1 << 8,
85 LINK_RESETTING = 0x2 << 12,
86 LINK_PEER_RESET = 0xd << 16,
87 LINK_FAILINGOVER = 0xf << 20,
88 LINK_SYNCHING = 0xc << 24
89 };
90
91 /* Link FSM state checking routines
92 */
93 static int link_is_up(struct tipc_link *l)
94 {
95 return l->state & (LINK_ESTABLISHED | LINK_SYNCHING);
96 }
97
98 static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
99 struct sk_buff_head *xmitq);
100 static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
101 u16 rcvgap, int tolerance, int priority,
102 struct sk_buff_head *xmitq);
103 static void link_print(struct tipc_link *l_ptr, const char *str);
104 static void tipc_link_build_nack_msg(struct tipc_link *l,
105 struct sk_buff_head *xmitq);
106 static void tipc_link_build_bc_init_msg(struct tipc_link *l,
107 struct sk_buff_head *xmitq);
108 static bool tipc_link_release_pkts(struct tipc_link *l, u16 to);
109
110 /*
111 * Simple non-static link routines (i.e. referenced outside this file)
112 */
113 bool tipc_link_is_up(struct tipc_link *l)
114 {
115 return link_is_up(l);
116 }
117
118 bool tipc_link_peer_is_down(struct tipc_link *l)
119 {
120 return l->state == LINK_PEER_RESET;
121 }
122
123 bool tipc_link_is_reset(struct tipc_link *l)
124 {
125 return l->state & (LINK_RESET | LINK_FAILINGOVER | LINK_ESTABLISHING);
126 }
127
128 bool tipc_link_is_establishing(struct tipc_link *l)
129 {
130 return l->state == LINK_ESTABLISHING;
131 }
132
133 bool tipc_link_is_synching(struct tipc_link *l)
134 {
135 return l->state == LINK_SYNCHING;
136 }
137
138 bool tipc_link_is_failingover(struct tipc_link *l)
139 {
140 return l->state == LINK_FAILINGOVER;
141 }
142
143 bool tipc_link_is_blocked(struct tipc_link *l)
144 {
145 return l->state & (LINK_RESETTING | LINK_PEER_RESET | LINK_FAILINGOVER);
146 }
147
148 static bool link_is_bc_sndlink(struct tipc_link *l)
149 {
150 return !l->bc_sndlink;
151 }
152
153 static bool link_is_bc_rcvlink(struct tipc_link *l)
154 {
155 return ((l->bc_rcvlink == l) && !link_is_bc_sndlink(l));
156 }
157
158 int tipc_link_is_active(struct tipc_link *l)
159 {
160 return l->active;
161 }
162
163 void tipc_link_set_active(struct tipc_link *l, bool active)
164 {
165 l->active = active;
166 }
167
168 void tipc_link_add_bc_peer(struct tipc_link *snd_l,
169 struct tipc_link *uc_l,
170 struct sk_buff_head *xmitq)
171 {
172 struct tipc_link *rcv_l = uc_l->bc_rcvlink;
173
174 snd_l->ackers++;
175 rcv_l->acked = snd_l->snd_nxt - 1;
176 tipc_link_build_bc_init_msg(uc_l, xmitq);
177 }
178
179 void tipc_link_remove_bc_peer(struct tipc_link *snd_l,
180 struct tipc_link *rcv_l,
181 struct sk_buff_head *xmitq)
182 {
183 u16 ack = snd_l->snd_nxt - 1;
184
185 snd_l->ackers--;
186 tipc_link_bc_ack_rcv(rcv_l, ack, xmitq);
187 tipc_link_reset(rcv_l);
188 rcv_l->state = LINK_RESET;
189 if (!snd_l->ackers) {
190 tipc_link_reset(snd_l);
191 __skb_queue_purge(xmitq);
192 }
193 }
194
195 int tipc_link_bc_peers(struct tipc_link *l)
196 {
197 return l->ackers;
198 }
199
200 void tipc_link_set_mtu(struct tipc_link *l, int mtu)
201 {
202 l->mtu = mtu;
203 }
204
205 int tipc_link_mtu(struct tipc_link *l)
206 {
207 return l->mtu;
208 }
209
210 static u32 link_own_addr(struct tipc_link *l)
211 {
212 return msg_prevnode(l->pmsg);
213 }
214
215 /**
216 * tipc_link_create - create a new link
217 * @n: pointer to associated node
218 * @if_name: associated interface name
219 * @bearer_id: id (index) of associated bearer
220 * @tolerance: link tolerance to be used by link
221 * @net_plane: network plane (A,B,c..) this link belongs to
222 * @mtu: mtu to be advertised by link
223 * @priority: priority to be used by link
224 * @window: send window to be used by link
225 * @session: session to be used by link
226 * @ownnode: identity of own node
227 * @peer: node id of peer node
228 * @peer_caps: bitmap describing peer node capabilities
229 * @bc_sndlink: the namespace global link used for broadcast sending
230 * @bc_rcvlink: the peer specific link used for broadcast reception
231 * @inputq: queue to put messages ready for delivery
232 * @namedq: queue to put binding table update messages ready for delivery
233 * @link: return value, pointer to put the created link
234 *
235 * Returns true if link was created, otherwise false
236 */
237 bool tipc_link_create(struct net *net, char *if_name, int bearer_id,
238 int tolerance, char net_plane, u32 mtu, int priority,
239 int window, u32 session, u32 ownnode, u32 peer,
240 u16 peer_caps,
241 struct tipc_link *bc_sndlink,
242 struct tipc_link *bc_rcvlink,
243 struct sk_buff_head *inputq,
244 struct sk_buff_head *namedq,
245 struct tipc_link **link)
246 {
247 struct tipc_link *l;
248 struct tipc_msg *hdr;
249
250 l = kzalloc(sizeof(*l), GFP_ATOMIC);
251 if (!l)
252 return false;
253 *link = l;
254 l->pmsg = (struct tipc_msg *)&l->proto_msg;
255 hdr = l->pmsg;
256 tipc_msg_init(ownnode, hdr, LINK_PROTOCOL, RESET_MSG, INT_H_SIZE, peer);
257 msg_set_size(hdr, sizeof(l->proto_msg));
258 msg_set_session(hdr, session);
259 msg_set_bearer_id(hdr, l->bearer_id);
260
261 /* Note: peer i/f name is completed by reset/activate message */
262 sprintf(l->name, "%u.%u.%u:%s-%u.%u.%u:unknown",
263 tipc_zone(ownnode), tipc_cluster(ownnode), tipc_node(ownnode),
264 if_name, tipc_zone(peer), tipc_cluster(peer), tipc_node(peer));
265 strcpy((char *)msg_data(hdr), if_name);
266
267 l->addr = peer;
268 l->peer_caps = peer_caps;
269 l->net = net;
270 l->peer_session = WILDCARD_SESSION;
271 l->bearer_id = bearer_id;
272 l->tolerance = tolerance;
273 l->net_plane = net_plane;
274 l->advertised_mtu = mtu;
275 l->mtu = mtu;
276 l->priority = priority;
277 tipc_link_set_queue_limits(l, window);
278 l->ackers = 1;
279 l->bc_sndlink = bc_sndlink;
280 l->bc_rcvlink = bc_rcvlink;
281 l->inputq = inputq;
282 l->namedq = namedq;
283 l->state = LINK_RESETTING;
284 __skb_queue_head_init(&l->transmq);
285 __skb_queue_head_init(&l->backlogq);
286 __skb_queue_head_init(&l->deferdq);
287 skb_queue_head_init(&l->wakeupq);
288 skb_queue_head_init(l->inputq);
289 return true;
290 }
291
292 /**
293 * tipc_link_bc_create - create new link to be used for broadcast
294 * @n: pointer to associated node
295 * @mtu: mtu to be used
296 * @window: send window to be used
297 * @inputq: queue to put messages ready for delivery
298 * @namedq: queue to put binding table update messages ready for delivery
299 * @link: return value, pointer to put the created link
300 *
301 * Returns true if link was created, otherwise false
302 */
303 bool tipc_link_bc_create(struct net *net, u32 ownnode, u32 peer,
304 int mtu, int window, u16 peer_caps,
305 struct sk_buff_head *inputq,
306 struct sk_buff_head *namedq,
307 struct tipc_link *bc_sndlink,
308 struct tipc_link **link)
309 {
310 struct tipc_link *l;
311
312 if (!tipc_link_create(net, "", MAX_BEARERS, 0, 'Z', mtu, 0, window,
313 0, ownnode, peer, peer_caps, bc_sndlink,
314 NULL, inputq, namedq, link))
315 return false;
316
317 l = *link;
318 strcpy(l->name, tipc_bclink_name);
319 tipc_link_reset(l);
320 l->state = LINK_RESET;
321 l->ackers = 0;
322 l->bc_rcvlink = l;
323
324 /* Broadcast send link is always up */
325 if (link_is_bc_sndlink(l))
326 l->state = LINK_ESTABLISHED;
327
328 return true;
329 }
330
331 /**
332 * tipc_link_fsm_evt - link finite state machine
333 * @l: pointer to link
334 * @evt: state machine event to be processed
335 */
336 int tipc_link_fsm_evt(struct tipc_link *l, int evt)
337 {
338 int rc = 0;
339
340 switch (l->state) {
341 case LINK_RESETTING:
342 switch (evt) {
343 case LINK_PEER_RESET_EVT:
344 l->state = LINK_PEER_RESET;
345 break;
346 case LINK_RESET_EVT:
347 l->state = LINK_RESET;
348 break;
349 case LINK_FAILURE_EVT:
350 case LINK_FAILOVER_BEGIN_EVT:
351 case LINK_ESTABLISH_EVT:
352 case LINK_FAILOVER_END_EVT:
353 case LINK_SYNCH_BEGIN_EVT:
354 case LINK_SYNCH_END_EVT:
355 default:
356 goto illegal_evt;
357 }
358 break;
359 case LINK_RESET:
360 switch (evt) {
361 case LINK_PEER_RESET_EVT:
362 l->state = LINK_ESTABLISHING;
363 break;
364 case LINK_FAILOVER_BEGIN_EVT:
365 l->state = LINK_FAILINGOVER;
366 case LINK_FAILURE_EVT:
367 case LINK_RESET_EVT:
368 case LINK_ESTABLISH_EVT:
369 case LINK_FAILOVER_END_EVT:
370 break;
371 case LINK_SYNCH_BEGIN_EVT:
372 case LINK_SYNCH_END_EVT:
373 default:
374 goto illegal_evt;
375 }
376 break;
377 case LINK_PEER_RESET:
378 switch (evt) {
379 case LINK_RESET_EVT:
380 l->state = LINK_ESTABLISHING;
381 break;
382 case LINK_PEER_RESET_EVT:
383 case LINK_ESTABLISH_EVT:
384 case LINK_FAILURE_EVT:
385 break;
386 case LINK_SYNCH_BEGIN_EVT:
387 case LINK_SYNCH_END_EVT:
388 case LINK_FAILOVER_BEGIN_EVT:
389 case LINK_FAILOVER_END_EVT:
390 default:
391 goto illegal_evt;
392 }
393 break;
394 case LINK_FAILINGOVER:
395 switch (evt) {
396 case LINK_FAILOVER_END_EVT:
397 l->state = LINK_RESET;
398 break;
399 case LINK_PEER_RESET_EVT:
400 case LINK_RESET_EVT:
401 case LINK_ESTABLISH_EVT:
402 case LINK_FAILURE_EVT:
403 break;
404 case LINK_FAILOVER_BEGIN_EVT:
405 case LINK_SYNCH_BEGIN_EVT:
406 case LINK_SYNCH_END_EVT:
407 default:
408 goto illegal_evt;
409 }
410 break;
411 case LINK_ESTABLISHING:
412 switch (evt) {
413 case LINK_ESTABLISH_EVT:
414 l->state = LINK_ESTABLISHED;
415 break;
416 case LINK_FAILOVER_BEGIN_EVT:
417 l->state = LINK_FAILINGOVER;
418 break;
419 case LINK_RESET_EVT:
420 l->state = LINK_RESET;
421 break;
422 case LINK_FAILURE_EVT:
423 case LINK_PEER_RESET_EVT:
424 case LINK_SYNCH_BEGIN_EVT:
425 case LINK_FAILOVER_END_EVT:
426 break;
427 case LINK_SYNCH_END_EVT:
428 default:
429 goto illegal_evt;
430 }
431 break;
432 case LINK_ESTABLISHED:
433 switch (evt) {
434 case LINK_PEER_RESET_EVT:
435 l->state = LINK_PEER_RESET;
436 rc |= TIPC_LINK_DOWN_EVT;
437 break;
438 case LINK_FAILURE_EVT:
439 l->state = LINK_RESETTING;
440 rc |= TIPC_LINK_DOWN_EVT;
441 break;
442 case LINK_RESET_EVT:
443 l->state = LINK_RESET;
444 break;
445 case LINK_ESTABLISH_EVT:
446 case LINK_SYNCH_END_EVT:
447 break;
448 case LINK_SYNCH_BEGIN_EVT:
449 l->state = LINK_SYNCHING;
450 break;
451 case LINK_FAILOVER_BEGIN_EVT:
452 case LINK_FAILOVER_END_EVT:
453 default:
454 goto illegal_evt;
455 }
456 break;
457 case LINK_SYNCHING:
458 switch (evt) {
459 case LINK_PEER_RESET_EVT:
460 l->state = LINK_PEER_RESET;
461 rc |= TIPC_LINK_DOWN_EVT;
462 break;
463 case LINK_FAILURE_EVT:
464 l->state = LINK_RESETTING;
465 rc |= TIPC_LINK_DOWN_EVT;
466 break;
467 case LINK_RESET_EVT:
468 l->state = LINK_RESET;
469 break;
470 case LINK_ESTABLISH_EVT:
471 case LINK_SYNCH_BEGIN_EVT:
472 break;
473 case LINK_SYNCH_END_EVT:
474 l->state = LINK_ESTABLISHED;
475 break;
476 case LINK_FAILOVER_BEGIN_EVT:
477 case LINK_FAILOVER_END_EVT:
478 default:
479 goto illegal_evt;
480 }
481 break;
482 default:
483 pr_err("Unknown FSM state %x in %s\n", l->state, l->name);
484 }
485 return rc;
486 illegal_evt:
487 pr_err("Illegal FSM event %x in state %x on link %s\n",
488 evt, l->state, l->name);
489 return rc;
490 }
491
492 /* link_profile_stats - update statistical profiling of traffic
493 */
494 static void link_profile_stats(struct tipc_link *l)
495 {
496 struct sk_buff *skb;
497 struct tipc_msg *msg;
498 int length;
499
500 /* Update counters used in statistical profiling of send traffic */
501 l->stats.accu_queue_sz += skb_queue_len(&l->transmq);
502 l->stats.queue_sz_counts++;
503
504 skb = skb_peek(&l->transmq);
505 if (!skb)
506 return;
507 msg = buf_msg(skb);
508 length = msg_size(msg);
509
510 if (msg_user(msg) == MSG_FRAGMENTER) {
511 if (msg_type(msg) != FIRST_FRAGMENT)
512 return;
513 length = msg_size(msg_get_wrapped(msg));
514 }
515 l->stats.msg_lengths_total += length;
516 l->stats.msg_length_counts++;
517 if (length <= 64)
518 l->stats.msg_length_profile[0]++;
519 else if (length <= 256)
520 l->stats.msg_length_profile[1]++;
521 else if (length <= 1024)
522 l->stats.msg_length_profile[2]++;
523 else if (length <= 4096)
524 l->stats.msg_length_profile[3]++;
525 else if (length <= 16384)
526 l->stats.msg_length_profile[4]++;
527 else if (length <= 32768)
528 l->stats.msg_length_profile[5]++;
529 else
530 l->stats.msg_length_profile[6]++;
531 }
532
533 /* tipc_link_timeout - perform periodic task as instructed from node timeout
534 */
535 /* tipc_link_timeout - perform periodic task as instructed from node timeout
536 */
537 int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq)
538 {
539 int rc = 0;
540 int mtyp = STATE_MSG;
541 bool xmit = false;
542 bool prb = false;
543 u16 bc_snt = l->bc_sndlink->snd_nxt - 1;
544 u16 bc_acked = l->bc_rcvlink->acked;
545 bool bc_up = link_is_up(l->bc_rcvlink);
546
547 link_profile_stats(l);
548
549 switch (l->state) {
550 case LINK_ESTABLISHED:
551 case LINK_SYNCHING:
552 if (!l->silent_intv_cnt) {
553 if (bc_up && (bc_acked != bc_snt))
554 xmit = true;
555 } else if (l->silent_intv_cnt <= l->abort_limit) {
556 xmit = true;
557 prb = true;
558 } else {
559 rc |= tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
560 }
561 l->silent_intv_cnt++;
562 break;
563 case LINK_RESET:
564 xmit = true;
565 mtyp = RESET_MSG;
566 break;
567 case LINK_ESTABLISHING:
568 xmit = true;
569 mtyp = ACTIVATE_MSG;
570 break;
571 case LINK_PEER_RESET:
572 case LINK_RESETTING:
573 case LINK_FAILINGOVER:
574 break;
575 default:
576 break;
577 }
578
579 if (xmit)
580 tipc_link_build_proto_msg(l, mtyp, prb, 0, 0, 0, xmitq);
581
582 return rc;
583 }
584
585 /**
586 * link_schedule_user - schedule a message sender for wakeup after congestion
587 * @link: congested link
588 * @list: message that was attempted sent
589 * Create pseudo msg to send back to user when congestion abates
590 * Does not consume buffer list
591 */
592 static int link_schedule_user(struct tipc_link *link, struct sk_buff_head *list)
593 {
594 struct tipc_msg *msg = buf_msg(skb_peek(list));
595 int imp = msg_importance(msg);
596 u32 oport = msg_origport(msg);
597 u32 addr = link_own_addr(link);
598 struct sk_buff *skb;
599
600 /* This really cannot happen... */
601 if (unlikely(imp > TIPC_CRITICAL_IMPORTANCE)) {
602 pr_warn("%s<%s>, send queue full", link_rst_msg, link->name);
603 return -ENOBUFS;
604 }
605 /* Non-blocking sender: */
606 if (TIPC_SKB_CB(skb_peek(list))->wakeup_pending)
607 return -ELINKCONG;
608
609 /* Create and schedule wakeup pseudo message */
610 skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0,
611 addr, addr, oport, 0, 0);
612 if (!skb)
613 return -ENOBUFS;
614 TIPC_SKB_CB(skb)->chain_sz = skb_queue_len(list);
615 TIPC_SKB_CB(skb)->chain_imp = imp;
616 skb_queue_tail(&link->wakeupq, skb);
617 link->stats.link_congs++;
618 return -ELINKCONG;
619 }
620
621 /**
622 * link_prepare_wakeup - prepare users for wakeup after congestion
623 * @link: congested link
624 * Move a number of waiting users, as permitted by available space in
625 * the send queue, from link wait queue to node wait queue for wakeup
626 */
627 void link_prepare_wakeup(struct tipc_link *l)
628 {
629 int pnd[TIPC_SYSTEM_IMPORTANCE + 1] = {0,};
630 int imp, lim;
631 struct sk_buff *skb, *tmp;
632
633 skb_queue_walk_safe(&l->wakeupq, skb, tmp) {
634 imp = TIPC_SKB_CB(skb)->chain_imp;
635 lim = l->window + l->backlog[imp].limit;
636 pnd[imp] += TIPC_SKB_CB(skb)->chain_sz;
637 if ((pnd[imp] + l->backlog[imp].len) >= lim)
638 break;
639 skb_unlink(skb, &l->wakeupq);
640 skb_queue_tail(l->inputq, skb);
641 }
642 }
643
644 void tipc_link_reset(struct tipc_link *l)
645 {
646 /* Link is down, accept any session */
647 l->peer_session = WILDCARD_SESSION;
648
649 /* If peer is up, it only accepts an incremented session number */
650 msg_set_session(l->pmsg, msg_session(l->pmsg) + 1);
651
652 /* Prepare for renewed mtu size negotiation */
653 l->mtu = l->advertised_mtu;
654
655 /* Clean up all queues and counters: */
656 __skb_queue_purge(&l->transmq);
657 __skb_queue_purge(&l->deferdq);
658 skb_queue_splice_init(&l->wakeupq, l->inputq);
659 __skb_queue_purge(&l->backlogq);
660 l->backlog[TIPC_LOW_IMPORTANCE].len = 0;
661 l->backlog[TIPC_MEDIUM_IMPORTANCE].len = 0;
662 l->backlog[TIPC_HIGH_IMPORTANCE].len = 0;
663 l->backlog[TIPC_CRITICAL_IMPORTANCE].len = 0;
664 l->backlog[TIPC_SYSTEM_IMPORTANCE].len = 0;
665 kfree_skb(l->reasm_buf);
666 kfree_skb(l->failover_reasm_skb);
667 l->reasm_buf = NULL;
668 l->failover_reasm_skb = NULL;
669 l->rcv_unacked = 0;
670 l->snd_nxt = 1;
671 l->rcv_nxt = 1;
672 l->acked = 0;
673 l->silent_intv_cnt = 0;
674 l->stats.recv_info = 0;
675 l->stale_count = 0;
676 l->bc_peer_is_up = false;
677 link_reset_statistics(l);
678 }
679
680 /**
681 * tipc_link_xmit(): enqueue buffer list according to queue situation
682 * @link: link to use
683 * @list: chain of buffers containing message
684 * @xmitq: returned list of packets to be sent by caller
685 *
686 * Consumes the buffer chain, except when returning -ELINKCONG,
687 * since the caller then may want to make more send attempts.
688 * Returns 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS
689 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted
690 */
691 int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list,
692 struct sk_buff_head *xmitq)
693 {
694 struct tipc_msg *hdr = buf_msg(skb_peek(list));
695 unsigned int maxwin = l->window;
696 unsigned int i, imp = msg_importance(hdr);
697 unsigned int mtu = l->mtu;
698 u16 ack = l->rcv_nxt - 1;
699 u16 seqno = l->snd_nxt;
700 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
701 struct sk_buff_head *transmq = &l->transmq;
702 struct sk_buff_head *backlogq = &l->backlogq;
703 struct sk_buff *skb, *_skb, *bskb;
704
705 /* Match msg importance against this and all higher backlog limits: */
706 for (i = imp; i <= TIPC_SYSTEM_IMPORTANCE; i++) {
707 if (unlikely(l->backlog[i].len >= l->backlog[i].limit))
708 return link_schedule_user(l, list);
709 }
710 if (unlikely(msg_size(hdr) > mtu))
711 return -EMSGSIZE;
712
713 /* Prepare each packet for sending, and add to relevant queue: */
714 while (skb_queue_len(list)) {
715 skb = skb_peek(list);
716 hdr = buf_msg(skb);
717 msg_set_seqno(hdr, seqno);
718 msg_set_ack(hdr, ack);
719 msg_set_bcast_ack(hdr, bc_ack);
720
721 if (likely(skb_queue_len(transmq) < maxwin)) {
722 _skb = skb_clone(skb, GFP_ATOMIC);
723 if (!_skb)
724 return -ENOBUFS;
725 __skb_dequeue(list);
726 __skb_queue_tail(transmq, skb);
727 __skb_queue_tail(xmitq, _skb);
728 TIPC_SKB_CB(skb)->ackers = l->ackers;
729 l->rcv_unacked = 0;
730 seqno++;
731 continue;
732 }
733 if (tipc_msg_bundle(skb_peek_tail(backlogq), hdr, mtu)) {
734 kfree_skb(__skb_dequeue(list));
735 l->stats.sent_bundled++;
736 continue;
737 }
738 if (tipc_msg_make_bundle(&bskb, hdr, mtu, l->addr)) {
739 kfree_skb(__skb_dequeue(list));
740 __skb_queue_tail(backlogq, bskb);
741 l->backlog[msg_importance(buf_msg(bskb))].len++;
742 l->stats.sent_bundled++;
743 l->stats.sent_bundles++;
744 continue;
745 }
746 l->backlog[imp].len += skb_queue_len(list);
747 skb_queue_splice_tail_init(list, backlogq);
748 }
749 l->snd_nxt = seqno;
750 return 0;
751 }
752
753 void tipc_link_advance_backlog(struct tipc_link *l, struct sk_buff_head *xmitq)
754 {
755 struct sk_buff *skb, *_skb;
756 struct tipc_msg *hdr;
757 u16 seqno = l->snd_nxt;
758 u16 ack = l->rcv_nxt - 1;
759 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
760
761 while (skb_queue_len(&l->transmq) < l->window) {
762 skb = skb_peek(&l->backlogq);
763 if (!skb)
764 break;
765 _skb = skb_clone(skb, GFP_ATOMIC);
766 if (!_skb)
767 break;
768 __skb_dequeue(&l->backlogq);
769 hdr = buf_msg(skb);
770 l->backlog[msg_importance(hdr)].len--;
771 __skb_queue_tail(&l->transmq, skb);
772 __skb_queue_tail(xmitq, _skb);
773 TIPC_SKB_CB(skb)->ackers = l->ackers;
774 msg_set_seqno(hdr, seqno);
775 msg_set_ack(hdr, ack);
776 msg_set_bcast_ack(hdr, bc_ack);
777 l->rcv_unacked = 0;
778 seqno++;
779 }
780 l->snd_nxt = seqno;
781 }
782
783 static void link_retransmit_failure(struct tipc_link *l, struct sk_buff *skb)
784 {
785 struct tipc_msg *hdr = buf_msg(skb);
786
787 pr_warn("Retransmission failure on link <%s>\n", l->name);
788 link_print(l, "Resetting link ");
789 pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n",
790 msg_user(hdr), msg_type(hdr), msg_size(hdr), msg_errcode(hdr));
791 pr_info("sqno %u, prev: %x, src: %x\n",
792 msg_seqno(hdr), msg_prevnode(hdr), msg_orignode(hdr));
793 }
794
795 int tipc_link_retrans(struct tipc_link *l, u16 from, u16 to,
796 struct sk_buff_head *xmitq)
797 {
798 struct sk_buff *_skb, *skb = skb_peek(&l->transmq);
799 struct tipc_msg *hdr;
800 u16 ack = l->rcv_nxt - 1;
801 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
802
803 if (!skb)
804 return 0;
805
806 /* Detect repeated retransmit failures on same packet */
807 if (likely(l->last_retransm != buf_seqno(skb))) {
808 l->last_retransm = buf_seqno(skb);
809 l->stale_count = 1;
810 } else if (++l->stale_count > 100) {
811 link_retransmit_failure(l, skb);
812 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
813 }
814
815 /* Move forward to where retransmission should start */
816 skb_queue_walk(&l->transmq, skb) {
817 if (!less(buf_seqno(skb), from))
818 break;
819 }
820
821 skb_queue_walk_from(&l->transmq, skb) {
822 if (more(buf_seqno(skb), to))
823 break;
824 hdr = buf_msg(skb);
825 _skb = __pskb_copy(skb, MIN_H_SIZE, GFP_ATOMIC);
826 if (!_skb)
827 return 0;
828 hdr = buf_msg(_skb);
829 msg_set_ack(hdr, ack);
830 msg_set_bcast_ack(hdr, bc_ack);
831 _skb->priority = TC_PRIO_CONTROL;
832 __skb_queue_tail(xmitq, _skb);
833 l->stats.retransmitted++;
834 }
835 return 0;
836 }
837
838 /* tipc_data_input - deliver data and name distr msgs to upper layer
839 *
840 * Consumes buffer if message is of right type
841 * Node lock must be held
842 */
843 static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb,
844 struct sk_buff_head *inputq)
845 {
846 switch (msg_user(buf_msg(skb))) {
847 case TIPC_LOW_IMPORTANCE:
848 case TIPC_MEDIUM_IMPORTANCE:
849 case TIPC_HIGH_IMPORTANCE:
850 case TIPC_CRITICAL_IMPORTANCE:
851 case CONN_MANAGER:
852 skb_queue_tail(inputq, skb);
853 return true;
854 case NAME_DISTRIBUTOR:
855 l->bc_rcvlink->state = LINK_ESTABLISHED;
856 skb_queue_tail(l->namedq, skb);
857 return true;
858 case MSG_BUNDLER:
859 case TUNNEL_PROTOCOL:
860 case MSG_FRAGMENTER:
861 case BCAST_PROTOCOL:
862 return false;
863 default:
864 pr_warn("Dropping received illegal msg type\n");
865 kfree_skb(skb);
866 return false;
867 };
868 }
869
870 /* tipc_link_input - process packet that has passed link protocol check
871 *
872 * Consumes buffer
873 */
874 static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb,
875 struct sk_buff_head *inputq)
876 {
877 struct tipc_msg *hdr = buf_msg(skb);
878 struct sk_buff **reasm_skb = &l->reasm_buf;
879 struct sk_buff *iskb;
880 struct sk_buff_head tmpq;
881 int usr = msg_user(hdr);
882 int rc = 0;
883 int pos = 0;
884 int ipos = 0;
885
886 if (unlikely(usr == TUNNEL_PROTOCOL)) {
887 if (msg_type(hdr) == SYNCH_MSG) {
888 __skb_queue_purge(&l->deferdq);
889 goto drop;
890 }
891 if (!tipc_msg_extract(skb, &iskb, &ipos))
892 return rc;
893 kfree_skb(skb);
894 skb = iskb;
895 hdr = buf_msg(skb);
896 if (less(msg_seqno(hdr), l->drop_point))
897 goto drop;
898 if (tipc_data_input(l, skb, inputq))
899 return rc;
900 usr = msg_user(hdr);
901 reasm_skb = &l->failover_reasm_skb;
902 }
903
904 if (usr == MSG_BUNDLER) {
905 skb_queue_head_init(&tmpq);
906 l->stats.recv_bundles++;
907 l->stats.recv_bundled += msg_msgcnt(hdr);
908 while (tipc_msg_extract(skb, &iskb, &pos))
909 tipc_data_input(l, iskb, &tmpq);
910 tipc_skb_queue_splice_tail(&tmpq, inputq);
911 return 0;
912 } else if (usr == MSG_FRAGMENTER) {
913 l->stats.recv_fragments++;
914 if (tipc_buf_append(reasm_skb, &skb)) {
915 l->stats.recv_fragmented++;
916 tipc_data_input(l, skb, inputq);
917 } else if (!*reasm_skb && !link_is_bc_rcvlink(l)) {
918 pr_warn_ratelimited("Unable to build fragment list\n");
919 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
920 }
921 return 0;
922 } else if (usr == BCAST_PROTOCOL) {
923 tipc_bcast_lock(l->net);
924 tipc_link_bc_init_rcv(l->bc_rcvlink, hdr);
925 tipc_bcast_unlock(l->net);
926 }
927 drop:
928 kfree_skb(skb);
929 return 0;
930 }
931
932 static bool tipc_link_release_pkts(struct tipc_link *l, u16 acked)
933 {
934 bool released = false;
935 struct sk_buff *skb, *tmp;
936
937 skb_queue_walk_safe(&l->transmq, skb, tmp) {
938 if (more(buf_seqno(skb), acked))
939 break;
940 __skb_unlink(skb, &l->transmq);
941 kfree_skb(skb);
942 released = true;
943 }
944 return released;
945 }
946
947 /* tipc_link_build_ack_msg: prepare link acknowledge message for transmission
948 *
949 * Note that sending of broadcast ack is coordinated among nodes, to reduce
950 * risk of ack storms towards the sender
951 */
952 int tipc_link_build_ack_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
953 {
954 if (!l)
955 return 0;
956
957 /* Broadcast ACK must be sent via a unicast link => defer to caller */
958 if (link_is_bc_rcvlink(l)) {
959 if (((l->rcv_nxt ^ link_own_addr(l)) & 0xf) != 0xf)
960 return 0;
961 l->rcv_unacked = 0;
962 return TIPC_LINK_SND_BC_ACK;
963 }
964
965 /* Unicast ACK */
966 l->rcv_unacked = 0;
967 l->stats.sent_acks++;
968 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, xmitq);
969 return 0;
970 }
971
972 /* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message
973 */
974 void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
975 {
976 int mtyp = RESET_MSG;
977
978 if (l->state == LINK_ESTABLISHING)
979 mtyp = ACTIVATE_MSG;
980
981 tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, xmitq);
982 }
983
984 /* tipc_link_build_nack_msg: prepare link nack message for transmission
985 */
986 static void tipc_link_build_nack_msg(struct tipc_link *l,
987 struct sk_buff_head *xmitq)
988 {
989 u32 def_cnt = ++l->stats.deferred_recv;
990
991 if (link_is_bc_rcvlink(l))
992 return;
993
994 if ((skb_queue_len(&l->deferdq) == 1) || !(def_cnt % TIPC_NACK_INTV))
995 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, xmitq);
996 }
997
998 /* tipc_link_rcv - process TIPC packets/messages arriving from off-node
999 * @l: the link that should handle the message
1000 * @skb: TIPC packet
1001 * @xmitq: queue to place packets to be sent after this call
1002 */
1003 int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb,
1004 struct sk_buff_head *xmitq)
1005 {
1006 struct sk_buff_head *defq = &l->deferdq;
1007 struct tipc_msg *hdr;
1008 u16 seqno, rcv_nxt, win_lim;
1009 int rc = 0;
1010
1011 do {
1012 hdr = buf_msg(skb);
1013 seqno = msg_seqno(hdr);
1014 rcv_nxt = l->rcv_nxt;
1015 win_lim = rcv_nxt + TIPC_MAX_LINK_WIN;
1016
1017 /* Verify and update link state */
1018 if (unlikely(msg_user(hdr) == LINK_PROTOCOL))
1019 return tipc_link_proto_rcv(l, skb, xmitq);
1020
1021 if (unlikely(!link_is_up(l))) {
1022 if (l->state == LINK_ESTABLISHING)
1023 rc = TIPC_LINK_UP_EVT;
1024 goto drop;
1025 }
1026
1027 /* Don't send probe at next timeout expiration */
1028 l->silent_intv_cnt = 0;
1029
1030 /* Drop if outside receive window */
1031 if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) {
1032 l->stats.duplicates++;
1033 goto drop;
1034 }
1035
1036 /* Forward queues and wake up waiting users */
1037 if (likely(tipc_link_release_pkts(l, msg_ack(hdr)))) {
1038 tipc_link_advance_backlog(l, xmitq);
1039 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1040 link_prepare_wakeup(l);
1041 }
1042
1043 /* Defer delivery if sequence gap */
1044 if (unlikely(seqno != rcv_nxt)) {
1045 __tipc_skb_queue_sorted(defq, seqno, skb);
1046 tipc_link_build_nack_msg(l, xmitq);
1047 break;
1048 }
1049
1050 /* Deliver packet */
1051 l->rcv_nxt++;
1052 l->stats.recv_info++;
1053 if (!tipc_data_input(l, skb, l->inputq))
1054 rc |= tipc_link_input(l, skb, l->inputq);
1055 if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN))
1056 rc |= tipc_link_build_ack_msg(l, xmitq);
1057 if (unlikely(rc & ~TIPC_LINK_SND_BC_ACK))
1058 break;
1059 } while ((skb = __skb_dequeue(defq)));
1060
1061 return rc;
1062 drop:
1063 kfree_skb(skb);
1064 return rc;
1065 }
1066
1067 /*
1068 * Send protocol message to the other endpoint.
1069 */
1070 void tipc_link_proto_xmit(struct tipc_link *l, u32 msg_typ, int probe_msg,
1071 u32 gap, u32 tolerance, u32 priority)
1072 {
1073 struct sk_buff *skb = NULL;
1074 struct sk_buff_head xmitq;
1075
1076 __skb_queue_head_init(&xmitq);
1077 tipc_link_build_proto_msg(l, msg_typ, probe_msg, gap,
1078 tolerance, priority, &xmitq);
1079 skb = __skb_dequeue(&xmitq);
1080 if (!skb)
1081 return;
1082 tipc_bearer_xmit_skb(l->net, l->bearer_id, skb, l->media_addr);
1083 l->rcv_unacked = 0;
1084 }
1085
1086 static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
1087 u16 rcvgap, int tolerance, int priority,
1088 struct sk_buff_head *xmitq)
1089 {
1090 struct sk_buff *skb = NULL;
1091 struct tipc_msg *hdr = l->pmsg;
1092 bool node_up = link_is_up(l->bc_rcvlink);
1093
1094 /* Don't send protocol message during reset or link failover */
1095 if (tipc_link_is_blocked(l))
1096 return;
1097
1098 msg_set_type(hdr, mtyp);
1099 msg_set_net_plane(hdr, l->net_plane);
1100 msg_set_next_sent(hdr, l->snd_nxt);
1101 msg_set_ack(hdr, l->rcv_nxt - 1);
1102 msg_set_bcast_ack(hdr, l->bc_rcvlink->rcv_nxt - 1);
1103 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
1104 msg_set_link_tolerance(hdr, tolerance);
1105 msg_set_linkprio(hdr, priority);
1106 msg_set_redundant_link(hdr, node_up);
1107 msg_set_seq_gap(hdr, 0);
1108
1109 /* Compatibility: created msg must not be in sequence with pkt flow */
1110 msg_set_seqno(hdr, l->snd_nxt + U16_MAX / 2);
1111
1112 if (mtyp == STATE_MSG) {
1113 if (!tipc_link_is_up(l))
1114 return;
1115
1116 /* Override rcvgap if there are packets in deferred queue */
1117 if (!skb_queue_empty(&l->deferdq))
1118 rcvgap = buf_seqno(skb_peek(&l->deferdq)) - l->rcv_nxt;
1119 if (rcvgap) {
1120 msg_set_seq_gap(hdr, rcvgap);
1121 l->stats.sent_nacks++;
1122 }
1123 msg_set_probe(hdr, probe);
1124 if (probe)
1125 l->stats.sent_probes++;
1126 l->stats.sent_states++;
1127 l->rcv_unacked = 0;
1128 } else {
1129 /* RESET_MSG or ACTIVATE_MSG */
1130 msg_set_max_pkt(hdr, l->advertised_mtu);
1131 msg_set_ack(hdr, l->rcv_nxt - 1);
1132 msg_set_next_sent(hdr, 1);
1133 }
1134 skb = tipc_buf_acquire(msg_size(hdr));
1135 if (!skb)
1136 return;
1137 skb_copy_to_linear_data(skb, hdr, msg_size(hdr));
1138 skb->priority = TC_PRIO_CONTROL;
1139 __skb_queue_tail(xmitq, skb);
1140 }
1141
1142 /* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets
1143 * with contents of the link's transmit and backlog queues.
1144 */
1145 void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
1146 int mtyp, struct sk_buff_head *xmitq)
1147 {
1148 struct sk_buff *skb, *tnlskb;
1149 struct tipc_msg *hdr, tnlhdr;
1150 struct sk_buff_head *queue = &l->transmq;
1151 struct sk_buff_head tmpxq, tnlq;
1152 u16 pktlen, pktcnt, seqno = l->snd_nxt;
1153
1154 if (!tnl)
1155 return;
1156
1157 skb_queue_head_init(&tnlq);
1158 skb_queue_head_init(&tmpxq);
1159
1160 /* At least one packet required for safe algorithm => add dummy */
1161 skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1162 BASIC_H_SIZE, 0, l->addr, link_own_addr(l),
1163 0, 0, TIPC_ERR_NO_PORT);
1164 if (!skb) {
1165 pr_warn("%sunable to create tunnel packet\n", link_co_err);
1166 return;
1167 }
1168 skb_queue_tail(&tnlq, skb);
1169 tipc_link_xmit(l, &tnlq, &tmpxq);
1170 __skb_queue_purge(&tmpxq);
1171
1172 /* Initialize reusable tunnel packet header */
1173 tipc_msg_init(link_own_addr(l), &tnlhdr, TUNNEL_PROTOCOL,
1174 mtyp, INT_H_SIZE, l->addr);
1175 pktcnt = skb_queue_len(&l->transmq) + skb_queue_len(&l->backlogq);
1176 msg_set_msgcnt(&tnlhdr, pktcnt);
1177 msg_set_bearer_id(&tnlhdr, l->peer_bearer_id);
1178 tnl:
1179 /* Wrap each packet into a tunnel packet */
1180 skb_queue_walk(queue, skb) {
1181 hdr = buf_msg(skb);
1182 if (queue == &l->backlogq)
1183 msg_set_seqno(hdr, seqno++);
1184 pktlen = msg_size(hdr);
1185 msg_set_size(&tnlhdr, pktlen + INT_H_SIZE);
1186 tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE);
1187 if (!tnlskb) {
1188 pr_warn("%sunable to send packet\n", link_co_err);
1189 return;
1190 }
1191 skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE);
1192 skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen);
1193 __skb_queue_tail(&tnlq, tnlskb);
1194 }
1195 if (queue != &l->backlogq) {
1196 queue = &l->backlogq;
1197 goto tnl;
1198 }
1199
1200 tipc_link_xmit(tnl, &tnlq, xmitq);
1201
1202 if (mtyp == FAILOVER_MSG) {
1203 tnl->drop_point = l->rcv_nxt;
1204 tnl->failover_reasm_skb = l->reasm_buf;
1205 l->reasm_buf = NULL;
1206 }
1207 }
1208
1209 /* tipc_link_proto_rcv(): receive link level protocol message :
1210 * Note that network plane id propagates through the network, and may
1211 * change at any time. The node with lowest numerical id determines
1212 * network plane
1213 */
1214 static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
1215 struct sk_buff_head *xmitq)
1216 {
1217 struct tipc_msg *hdr = buf_msg(skb);
1218 u16 rcvgap = 0;
1219 u16 ack = msg_ack(hdr);
1220 u16 gap = msg_seq_gap(hdr);
1221 u16 peers_snd_nxt = msg_next_sent(hdr);
1222 u16 peers_tol = msg_link_tolerance(hdr);
1223 u16 peers_prio = msg_linkprio(hdr);
1224 u16 rcv_nxt = l->rcv_nxt;
1225 int mtyp = msg_type(hdr);
1226 char *if_name;
1227 int rc = 0;
1228
1229 if (tipc_link_is_blocked(l) || !xmitq)
1230 goto exit;
1231
1232 if (link_own_addr(l) > msg_prevnode(hdr))
1233 l->net_plane = msg_net_plane(hdr);
1234
1235 switch (mtyp) {
1236 case RESET_MSG:
1237
1238 /* Ignore duplicate RESET with old session number */
1239 if ((less_eq(msg_session(hdr), l->peer_session)) &&
1240 (l->peer_session != WILDCARD_SESSION))
1241 break;
1242 /* fall thru' */
1243
1244 case ACTIVATE_MSG:
1245 skb_linearize(skb);
1246 hdr = buf_msg(skb);
1247
1248 /* Complete own link name with peer's interface name */
1249 if_name = strrchr(l->name, ':') + 1;
1250 if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME)
1251 break;
1252 if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME)
1253 break;
1254 strncpy(if_name, msg_data(hdr), TIPC_MAX_IF_NAME);
1255
1256 /* Update own tolerance if peer indicates a non-zero value */
1257 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL))
1258 l->tolerance = peers_tol;
1259
1260 /* Update own priority if peer's priority is higher */
1261 if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
1262 l->priority = peers_prio;
1263
1264 /* ACTIVATE_MSG serves as PEER_RESET if link is already down */
1265 if ((mtyp == RESET_MSG) || !link_is_up(l))
1266 rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT);
1267
1268 /* ACTIVATE_MSG takes up link if it was already locally reset */
1269 if ((mtyp == ACTIVATE_MSG) && (l->state == LINK_ESTABLISHING))
1270 rc = TIPC_LINK_UP_EVT;
1271
1272 l->peer_session = msg_session(hdr);
1273 l->peer_bearer_id = msg_bearer_id(hdr);
1274 if (l->mtu > msg_max_pkt(hdr))
1275 l->mtu = msg_max_pkt(hdr);
1276 break;
1277
1278 case STATE_MSG:
1279
1280 /* Update own tolerance if peer indicates a non-zero value */
1281 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL))
1282 l->tolerance = peers_tol;
1283
1284 l->silent_intv_cnt = 0;
1285 l->stats.recv_states++;
1286 if (msg_probe(hdr))
1287 l->stats.recv_probes++;
1288
1289 if (!link_is_up(l)) {
1290 if (l->state == LINK_ESTABLISHING)
1291 rc = TIPC_LINK_UP_EVT;
1292 break;
1293 }
1294
1295 /* Send NACK if peer has sent pkts we haven't received yet */
1296 if (more(peers_snd_nxt, rcv_nxt) && !tipc_link_is_synching(l))
1297 rcvgap = peers_snd_nxt - l->rcv_nxt;
1298 if (rcvgap || (msg_probe(hdr)))
1299 tipc_link_build_proto_msg(l, STATE_MSG, 0, rcvgap,
1300 0, 0, xmitq);
1301 tipc_link_release_pkts(l, ack);
1302
1303 /* If NACK, retransmit will now start at right position */
1304 if (gap) {
1305 rc = tipc_link_retrans(l, ack + 1, ack + gap, xmitq);
1306 l->stats.recv_nacks++;
1307 }
1308
1309 tipc_link_advance_backlog(l, xmitq);
1310 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1311 link_prepare_wakeup(l);
1312 }
1313 exit:
1314 kfree_skb(skb);
1315 return rc;
1316 }
1317
1318 /* tipc_link_build_bc_proto_msg() - create broadcast protocol message
1319 */
1320 static bool tipc_link_build_bc_proto_msg(struct tipc_link *l, bool bcast,
1321 u16 peers_snd_nxt,
1322 struct sk_buff_head *xmitq)
1323 {
1324 struct sk_buff *skb;
1325 struct tipc_msg *hdr;
1326 struct sk_buff *dfrd_skb = skb_peek(&l->deferdq);
1327 u16 ack = l->rcv_nxt - 1;
1328 u16 gap_to = peers_snd_nxt - 1;
1329
1330 skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE,
1331 0, l->addr, link_own_addr(l), 0, 0, 0);
1332 if (!skb)
1333 return false;
1334 hdr = buf_msg(skb);
1335 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
1336 msg_set_bcast_ack(hdr, ack);
1337 msg_set_bcgap_after(hdr, ack);
1338 if (dfrd_skb)
1339 gap_to = buf_seqno(dfrd_skb) - 1;
1340 msg_set_bcgap_to(hdr, gap_to);
1341 msg_set_non_seq(hdr, bcast);
1342 __skb_queue_tail(xmitq, skb);
1343 return true;
1344 }
1345
1346 /* tipc_link_build_bc_init_msg() - synchronize broadcast link endpoints.
1347 *
1348 * Give a newly added peer node the sequence number where it should
1349 * start receiving and acking broadcast packets.
1350 */
1351 static void tipc_link_build_bc_init_msg(struct tipc_link *l,
1352 struct sk_buff_head *xmitq)
1353 {
1354 struct sk_buff_head list;
1355
1356 __skb_queue_head_init(&list);
1357 if (!tipc_link_build_bc_proto_msg(l->bc_rcvlink, false, 0, &list))
1358 return;
1359 tipc_link_xmit(l, &list, xmitq);
1360 }
1361
1362 /* tipc_link_bc_init_rcv - receive initial broadcast synch data from peer
1363 */
1364 void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr)
1365 {
1366 int mtyp = msg_type(hdr);
1367 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
1368
1369 if (link_is_up(l))
1370 return;
1371
1372 if (msg_user(hdr) == BCAST_PROTOCOL) {
1373 l->rcv_nxt = peers_snd_nxt;
1374 l->state = LINK_ESTABLISHED;
1375 return;
1376 }
1377
1378 if (l->peer_caps & TIPC_BCAST_SYNCH)
1379 return;
1380
1381 if (msg_peer_node_is_up(hdr))
1382 return;
1383
1384 /* Compatibility: accept older, less safe initial synch data */
1385 if ((mtyp == RESET_MSG) || (mtyp == ACTIVATE_MSG))
1386 l->rcv_nxt = peers_snd_nxt;
1387 }
1388
1389 /* tipc_link_bc_sync_rcv - update rcv link according to peer's send state
1390 */
1391 void tipc_link_bc_sync_rcv(struct tipc_link *l, struct tipc_msg *hdr,
1392 struct sk_buff_head *xmitq)
1393 {
1394 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
1395
1396 if (!link_is_up(l))
1397 return;
1398
1399 if (!msg_peer_node_is_up(hdr))
1400 return;
1401
1402 l->bc_peer_is_up = true;
1403
1404 /* Ignore if peers_snd_nxt goes beyond receive window */
1405 if (more(peers_snd_nxt, l->rcv_nxt + l->window))
1406 return;
1407
1408 if (!more(peers_snd_nxt, l->rcv_nxt)) {
1409 l->nack_state = BC_NACK_SND_CONDITIONAL;
1410 return;
1411 }
1412
1413 /* Don't NACK if one was recently sent or peeked */
1414 if (l->nack_state == BC_NACK_SND_SUPPRESS) {
1415 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
1416 return;
1417 }
1418
1419 /* Conditionally delay NACK sending until next synch rcv */
1420 if (l->nack_state == BC_NACK_SND_CONDITIONAL) {
1421 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
1422 if ((peers_snd_nxt - l->rcv_nxt) < TIPC_MIN_LINK_WIN)
1423 return;
1424 }
1425
1426 /* Send NACK now but suppress next one */
1427 tipc_link_build_bc_proto_msg(l, true, peers_snd_nxt, xmitq);
1428 l->nack_state = BC_NACK_SND_SUPPRESS;
1429 }
1430
1431 void tipc_link_bc_ack_rcv(struct tipc_link *l, u16 acked,
1432 struct sk_buff_head *xmitq)
1433 {
1434 struct sk_buff *skb, *tmp;
1435 struct tipc_link *snd_l = l->bc_sndlink;
1436
1437 if (!link_is_up(l) || !l->bc_peer_is_up)
1438 return;
1439
1440 if (!more(acked, l->acked))
1441 return;
1442
1443 /* Skip over packets peer has already acked */
1444 skb_queue_walk(&snd_l->transmq, skb) {
1445 if (more(buf_seqno(skb), l->acked))
1446 break;
1447 }
1448
1449 /* Update/release the packets peer is acking now */
1450 skb_queue_walk_from_safe(&snd_l->transmq, skb, tmp) {
1451 if (more(buf_seqno(skb), acked))
1452 break;
1453 if (!--TIPC_SKB_CB(skb)->ackers) {
1454 __skb_unlink(skb, &snd_l->transmq);
1455 kfree_skb(skb);
1456 }
1457 }
1458 l->acked = acked;
1459 tipc_link_advance_backlog(snd_l, xmitq);
1460 if (unlikely(!skb_queue_empty(&snd_l->wakeupq)))
1461 link_prepare_wakeup(snd_l);
1462 }
1463
1464 /* tipc_link_bc_nack_rcv(): receive broadcast nack message
1465 */
1466 int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb,
1467 struct sk_buff_head *xmitq)
1468 {
1469 struct tipc_msg *hdr = buf_msg(skb);
1470 u32 dnode = msg_destnode(hdr);
1471 int mtyp = msg_type(hdr);
1472 u16 acked = msg_bcast_ack(hdr);
1473 u16 from = acked + 1;
1474 u16 to = msg_bcgap_to(hdr);
1475 u16 peers_snd_nxt = to + 1;
1476 int rc = 0;
1477
1478 kfree_skb(skb);
1479
1480 if (!tipc_link_is_up(l) || !l->bc_peer_is_up)
1481 return 0;
1482
1483 if (mtyp != STATE_MSG)
1484 return 0;
1485
1486 if (dnode == link_own_addr(l)) {
1487 tipc_link_bc_ack_rcv(l, acked, xmitq);
1488 rc = tipc_link_retrans(l->bc_sndlink, from, to, xmitq);
1489 l->stats.recv_nacks++;
1490 return rc;
1491 }
1492
1493 /* Msg for other node => suppress own NACK at next sync if applicable */
1494 if (more(peers_snd_nxt, l->rcv_nxt) && !less(l->rcv_nxt, from))
1495 l->nack_state = BC_NACK_SND_SUPPRESS;
1496
1497 return 0;
1498 }
1499
1500 void tipc_link_set_queue_limits(struct tipc_link *l, u32 win)
1501 {
1502 int max_bulk = TIPC_MAX_PUBLICATIONS / (l->mtu / ITEM_SIZE);
1503
1504 l->window = win;
1505 l->backlog[TIPC_LOW_IMPORTANCE].limit = win / 2;
1506 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = win;
1507 l->backlog[TIPC_HIGH_IMPORTANCE].limit = win / 2 * 3;
1508 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = win * 2;
1509 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk;
1510 }
1511
1512 /**
1513 * link_reset_statistics - reset link statistics
1514 * @l_ptr: pointer to link
1515 */
1516 void link_reset_statistics(struct tipc_link *l_ptr)
1517 {
1518 memset(&l_ptr->stats, 0, sizeof(l_ptr->stats));
1519 l_ptr->stats.sent_info = l_ptr->snd_nxt;
1520 l_ptr->stats.recv_info = l_ptr->rcv_nxt;
1521 }
1522
1523 static void link_print(struct tipc_link *l, const char *str)
1524 {
1525 struct sk_buff *hskb = skb_peek(&l->transmq);
1526 u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1;
1527 u16 tail = l->snd_nxt - 1;
1528
1529 pr_info("%s Link <%s> state %x\n", str, l->name, l->state);
1530 pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n",
1531 skb_queue_len(&l->transmq), head, tail,
1532 skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt);
1533 }
1534
1535 /* Parse and validate nested (link) properties valid for media, bearer and link
1536 */
1537 int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
1538 {
1539 int err;
1540
1541 err = nla_parse_nested(props, TIPC_NLA_PROP_MAX, prop,
1542 tipc_nl_prop_policy);
1543 if (err)
1544 return err;
1545
1546 if (props[TIPC_NLA_PROP_PRIO]) {
1547 u32 prio;
1548
1549 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
1550 if (prio > TIPC_MAX_LINK_PRI)
1551 return -EINVAL;
1552 }
1553
1554 if (props[TIPC_NLA_PROP_TOL]) {
1555 u32 tol;
1556
1557 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
1558 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
1559 return -EINVAL;
1560 }
1561
1562 if (props[TIPC_NLA_PROP_WIN]) {
1563 u32 win;
1564
1565 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
1566 if ((win < TIPC_MIN_LINK_WIN) || (win > TIPC_MAX_LINK_WIN))
1567 return -EINVAL;
1568 }
1569
1570 return 0;
1571 }
1572
1573 static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
1574 {
1575 int i;
1576 struct nlattr *stats;
1577
1578 struct nla_map {
1579 u32 key;
1580 u32 val;
1581 };
1582
1583 struct nla_map map[] = {
1584 {TIPC_NLA_STATS_RX_INFO, s->recv_info},
1585 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
1586 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
1587 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
1588 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
1589 {TIPC_NLA_STATS_TX_INFO, s->sent_info},
1590 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
1591 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
1592 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
1593 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
1594 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
1595 s->msg_length_counts : 1},
1596 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
1597 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
1598 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
1599 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
1600 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
1601 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
1602 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
1603 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
1604 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
1605 {TIPC_NLA_STATS_RX_STATES, s->recv_states},
1606 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
1607 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
1608 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
1609 {TIPC_NLA_STATS_TX_STATES, s->sent_states},
1610 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
1611 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
1612 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
1613 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
1614 {TIPC_NLA_STATS_DUPLICATES, s->duplicates},
1615 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
1616 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
1617 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
1618 (s->accu_queue_sz / s->queue_sz_counts) : 0}
1619 };
1620
1621 stats = nla_nest_start(skb, TIPC_NLA_LINK_STATS);
1622 if (!stats)
1623 return -EMSGSIZE;
1624
1625 for (i = 0; i < ARRAY_SIZE(map); i++)
1626 if (nla_put_u32(skb, map[i].key, map[i].val))
1627 goto msg_full;
1628
1629 nla_nest_end(skb, stats);
1630
1631 return 0;
1632 msg_full:
1633 nla_nest_cancel(skb, stats);
1634
1635 return -EMSGSIZE;
1636 }
1637
1638 /* Caller should hold appropriate locks to protect the link */
1639 int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
1640 struct tipc_link *link, int nlflags)
1641 {
1642 int err;
1643 void *hdr;
1644 struct nlattr *attrs;
1645 struct nlattr *prop;
1646 struct tipc_net *tn = net_generic(net, tipc_net_id);
1647
1648 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
1649 nlflags, TIPC_NL_LINK_GET);
1650 if (!hdr)
1651 return -EMSGSIZE;
1652
1653 attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK);
1654 if (!attrs)
1655 goto msg_full;
1656
1657 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
1658 goto attr_msg_full;
1659 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST,
1660 tipc_cluster_mask(tn->own_addr)))
1661 goto attr_msg_full;
1662 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu))
1663 goto attr_msg_full;
1664 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->rcv_nxt))
1665 goto attr_msg_full;
1666 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->snd_nxt))
1667 goto attr_msg_full;
1668
1669 if (tipc_link_is_up(link))
1670 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
1671 goto attr_msg_full;
1672 if (link->active)
1673 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
1674 goto attr_msg_full;
1675
1676 prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP);
1677 if (!prop)
1678 goto attr_msg_full;
1679 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
1680 goto prop_msg_full;
1681 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
1682 goto prop_msg_full;
1683 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
1684 link->window))
1685 goto prop_msg_full;
1686 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
1687 goto prop_msg_full;
1688 nla_nest_end(msg->skb, prop);
1689
1690 err = __tipc_nl_add_stats(msg->skb, &link->stats);
1691 if (err)
1692 goto attr_msg_full;
1693
1694 nla_nest_end(msg->skb, attrs);
1695 genlmsg_end(msg->skb, hdr);
1696
1697 return 0;
1698
1699 prop_msg_full:
1700 nla_nest_cancel(msg->skb, prop);
1701 attr_msg_full:
1702 nla_nest_cancel(msg->skb, attrs);
1703 msg_full:
1704 genlmsg_cancel(msg->skb, hdr);
1705
1706 return -EMSGSIZE;
1707 }
Linux kernel - Deliverables
This page took 0.06694 seconds and 5 git commands to generate.