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Linux 4.19.133
[linux/fpc-iii.git] / net / tipc / link.c
blobcc9a0485536b3f682ec64fbef503722aa453f035
1 /*
2 * net/tipc/link.c: TIPC link code
3 *
4 * Copyright (c) 1996-2007, 2012-2016, Ericsson AB
5 * Copyright (c) 2004-2007, 2010-2013, Wind River Systems
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the names of the copyright holders nor the names of its
17 * contributors may be used to endorse or promote products derived from
18 * this software without specific prior written permission.
19 *
20 * Alternatively, this software may be distributed under the terms of the
21 * GNU General Public License ("GPL") version 2 as published by the Free
22 * Software Foundation.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34 * POSSIBILITY OF SUCH DAMAGE.
35 */
36
37 #include "core.h"
38 #include "subscr.h"
39 #include "link.h"
40 #include "bcast.h"
41 #include "socket.h"
42 #include "name_distr.h"
43 #include "discover.h"
44 #include "netlink.h"
45 #include "monitor.h"
46
47 #include <linux/pkt_sched.h>
48
49 struct tipc_stats {
50 u32 sent_pkts;
51 u32 recv_pkts;
52 u32 sent_states;
53 u32 recv_states;
54 u32 sent_probes;
55 u32 recv_probes;
56 u32 sent_nacks;
57 u32 recv_nacks;
58 u32 sent_acks;
59 u32 sent_bundled;
60 u32 sent_bundles;
61 u32 recv_bundled;
62 u32 recv_bundles;
63 u32 retransmitted;
64 u32 sent_fragmented;
65 u32 sent_fragments;
66 u32 recv_fragmented;
67 u32 recv_fragments;
68 u32 link_congs; /* # port sends blocked by congestion */
69 u32 deferred_recv;
70 u32 duplicates;
71 u32 max_queue_sz; /* send queue size high water mark */
72 u32 accu_queue_sz; /* used for send queue size profiling */
73 u32 queue_sz_counts; /* used for send queue size profiling */
74 u32 msg_length_counts; /* used for message length profiling */
75 u32 msg_lengths_total; /* used for message length profiling */
76 u32 msg_length_profile[7]; /* used for msg. length profiling */
77 };
78
79 /**
80 * struct tipc_link - TIPC link data structure
81 * @addr: network address of link's peer node
82 * @name: link name character string
83 * @media_addr: media address to use when sending messages over link
84 * @timer: link timer
85 * @net: pointer to namespace struct
86 * @refcnt: reference counter for permanent references (owner node & timer)
87 * @peer_session: link session # being used by peer end of link
88 * @peer_bearer_id: bearer id used by link's peer endpoint
89 * @bearer_id: local bearer id used by link
90 * @tolerance: minimum link continuity loss needed to reset link [in ms]
91 * @abort_limit: # of unacknowledged continuity probes needed to reset link
92 * @state: current state of link FSM
93 * @peer_caps: bitmap describing capabilities of peer node
94 * @silent_intv_cnt: # of timer intervals without any reception from peer
95 * @proto_msg: template for control messages generated by link
96 * @pmsg: convenience pointer to "proto_msg" field
97 * @priority: current link priority
98 * @net_plane: current link network plane ('A' through 'H')
99 * @mon_state: cookie with information needed by link monitor
100 * @backlog_limit: backlog queue congestion thresholds (indexed by importance)
101 * @exp_msg_count: # of tunnelled messages expected during link changeover
102 * @reset_rcv_checkpt: seq # of last acknowledged message at time of link reset
103 * @mtu: current maximum packet size for this link
104 * @advertised_mtu: advertised own mtu when link is being established
105 * @transmitq: queue for sent, non-acked messages
106 * @backlogq: queue for messages waiting to be sent
107 * @snt_nxt: next sequence number to use for outbound messages
108 * @last_retransmitted: sequence number of most recently retransmitted message
109 * @stale_cnt: counter for number of identical retransmit attempts
110 * @stale_limit: time when repeated identical retransmits must force link reset
111 * @ackers: # of peers that needs to ack each packet before it can be released
112 * @acked: # last packet acked by a certain peer. Used for broadcast.
113 * @rcv_nxt: next sequence number to expect for inbound messages
114 * @deferred_queue: deferred queue saved OOS b'cast message received from node
115 * @unacked_window: # of inbound messages rx'd without ack'ing back to peer
116 * @inputq: buffer queue for messages to be delivered upwards
117 * @namedq: buffer queue for name table messages to be delivered upwards
118 * @next_out: ptr to first unsent outbound message in queue
119 * @wakeupq: linked list of wakeup msgs waiting for link congestion to abate
120 * @long_msg_seq_no: next identifier to use for outbound fragmented messages
121 * @reasm_buf: head of partially reassembled inbound message fragments
122 * @bc_rcvr: marks that this is a broadcast receiver link
123 * @stats: collects statistics regarding link activity
124 */
125 struct tipc_link {
126 u32 addr;
127 char name[TIPC_MAX_LINK_NAME];
128 struct net *net;
129
130 /* Management and link supervision data */
131 u16 peer_session;
132 u16 session;
133 u16 snd_nxt_state;
134 u16 rcv_nxt_state;
135 u32 peer_bearer_id;
136 u32 bearer_id;
137 u32 tolerance;
138 u32 abort_limit;
139 u32 state;
140 u16 peer_caps;
141 bool in_session;
142 bool active;
143 u32 silent_intv_cnt;
144 char if_name[TIPC_MAX_IF_NAME];
145 u32 priority;
146 char net_plane;
147 struct tipc_mon_state mon_state;
148 u16 rst_cnt;
149
150 /* Failover/synch */
151 u16 drop_point;
152 struct sk_buff *failover_reasm_skb;
153
154 /* Max packet negotiation */
155 u16 mtu;
156 u16 advertised_mtu;
157
158 /* Sending */
159 struct sk_buff_head transmq;
160 struct sk_buff_head backlogq;
161 struct {
162 u16 len;
163 u16 limit;
164 struct sk_buff *target_bskb;
165 } backlog[5];
166 u16 snd_nxt;
167 u16 last_retransm;
168 u16 window;
169 u16 stale_cnt;
170 unsigned long stale_limit;
171
172 /* Reception */
173 u16 rcv_nxt;
174 u32 rcv_unacked;
175 struct sk_buff_head deferdq;
176 struct sk_buff_head *inputq;
177 struct sk_buff_head *namedq;
178
179 /* Congestion handling */
180 struct sk_buff_head wakeupq;
181
182 /* Fragmentation/reassembly */
183 struct sk_buff *reasm_buf;
184
185 /* Broadcast */
186 u16 ackers;
187 u16 acked;
188 struct tipc_link *bc_rcvlink;
189 struct tipc_link *bc_sndlink;
190 unsigned long prev_retr;
191 u16 prev_from;
192 u16 prev_to;
193 u8 nack_state;
194 bool bc_peer_is_up;
195
196 /* Statistics */
197 struct tipc_stats stats;
198 };
199
200 /*
201 * Error message prefixes
202 */
203 static const char *link_co_err = "Link tunneling error, ";
204 static const char *link_rst_msg = "Resetting link ";
205
206 /* Send states for broadcast NACKs
207 */
208 enum {
209 BC_NACK_SND_CONDITIONAL,
210 BC_NACK_SND_UNCONDITIONAL,
211 BC_NACK_SND_SUPPRESS,
212 };
213
214 #define TIPC_BC_RETR_LIMIT 10 /* [ms] */
215
216 /*
217 * Interval between NACKs when packets arrive out of order
218 */
219 #define TIPC_NACK_INTV (TIPC_MIN_LINK_WIN * 2)
220
221 /* Link FSM states:
222 */
223 enum {
224 LINK_ESTABLISHED = 0xe,
225 LINK_ESTABLISHING = 0xe << 4,
226 LINK_RESET = 0x1 << 8,
227 LINK_RESETTING = 0x2 << 12,
228 LINK_PEER_RESET = 0xd << 16,
229 LINK_FAILINGOVER = 0xf << 20,
230 LINK_SYNCHING = 0xc << 24
231 };
232
233 /* Link FSM state checking routines
234 */
235 static int link_is_up(struct tipc_link *l)
236 {
237 return l->state & (LINK_ESTABLISHED | LINK_SYNCHING);
238 }
239
240 static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
241 struct sk_buff_head *xmitq);
242 static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
243 bool probe_reply, u16 rcvgap,
244 int tolerance, int priority,
245 struct sk_buff_head *xmitq);
246 static void link_print(struct tipc_link *l, const char *str);
247 static int tipc_link_build_nack_msg(struct tipc_link *l,
248 struct sk_buff_head *xmitq);
249 static void tipc_link_build_bc_init_msg(struct tipc_link *l,
250 struct sk_buff_head *xmitq);
251 static bool tipc_link_release_pkts(struct tipc_link *l, u16 to);
252
253 /*
254 * Simple non-static link routines (i.e. referenced outside this file)
255 */
256 bool tipc_link_is_up(struct tipc_link *l)
257 {
258 return link_is_up(l);
259 }
260
261 bool tipc_link_peer_is_down(struct tipc_link *l)
262 {
263 return l->state == LINK_PEER_RESET;
264 }
265
266 bool tipc_link_is_reset(struct tipc_link *l)
267 {
268 return l->state & (LINK_RESET | LINK_FAILINGOVER | LINK_ESTABLISHING);
269 }
270
271 bool tipc_link_is_establishing(struct tipc_link *l)
272 {
273 return l->state == LINK_ESTABLISHING;
274 }
275
276 bool tipc_link_is_synching(struct tipc_link *l)
277 {
278 return l->state == LINK_SYNCHING;
279 }
280
281 bool tipc_link_is_failingover(struct tipc_link *l)
282 {
283 return l->state == LINK_FAILINGOVER;
284 }
285
286 bool tipc_link_is_blocked(struct tipc_link *l)
287 {
288 return l->state & (LINK_RESETTING | LINK_PEER_RESET | LINK_FAILINGOVER);
289 }
290
291 static bool link_is_bc_sndlink(struct tipc_link *l)
292 {
293 return !l->bc_sndlink;
294 }
295
296 static bool link_is_bc_rcvlink(struct tipc_link *l)
297 {
298 return ((l->bc_rcvlink == l) && !link_is_bc_sndlink(l));
299 }
300
301 void tipc_link_set_active(struct tipc_link *l, bool active)
302 {
303 l->active = active;
304 }
305
306 u32 tipc_link_id(struct tipc_link *l)
307 {
308 return l->peer_bearer_id << 16 | l->bearer_id;
309 }
310
311 int tipc_link_window(struct tipc_link *l)
312 {
313 return l->window;
314 }
315
316 int tipc_link_prio(struct tipc_link *l)
317 {
318 return l->priority;
319 }
320
321 unsigned long tipc_link_tolerance(struct tipc_link *l)
322 {
323 return l->tolerance;
324 }
325
326 struct sk_buff_head *tipc_link_inputq(struct tipc_link *l)
327 {
328 return l->inputq;
329 }
330
331 char tipc_link_plane(struct tipc_link *l)
332 {
333 return l->net_plane;
334 }
335
336 void tipc_link_update_caps(struct tipc_link *l, u16 capabilities)
337 {
338 l->peer_caps = capabilities;
339 }
340
341 void tipc_link_add_bc_peer(struct tipc_link *snd_l,
342 struct tipc_link *uc_l,
343 struct sk_buff_head *xmitq)
344 {
345 struct tipc_link *rcv_l = uc_l->bc_rcvlink;
346
347 snd_l->ackers++;
348 rcv_l->acked = snd_l->snd_nxt - 1;
349 snd_l->state = LINK_ESTABLISHED;
350 tipc_link_build_bc_init_msg(uc_l, xmitq);
351 }
352
353 void tipc_link_remove_bc_peer(struct tipc_link *snd_l,
354 struct tipc_link *rcv_l,
355 struct sk_buff_head *xmitq)
356 {
357 u16 ack = snd_l->snd_nxt - 1;
358
359 snd_l->ackers--;
360 rcv_l->bc_peer_is_up = true;
361 rcv_l->state = LINK_ESTABLISHED;
362 tipc_link_bc_ack_rcv(rcv_l, ack, xmitq);
363 tipc_link_reset(rcv_l);
364 rcv_l->state = LINK_RESET;
365 if (!snd_l->ackers) {
366 tipc_link_reset(snd_l);
367 snd_l->state = LINK_RESET;
368 __skb_queue_purge(xmitq);
369 }
370 }
371
372 int tipc_link_bc_peers(struct tipc_link *l)
373 {
374 return l->ackers;
375 }
376
377 static u16 link_bc_rcv_gap(struct tipc_link *l)
378 {
379 struct sk_buff *skb = skb_peek(&l->deferdq);
380 u16 gap = 0;
381
382 if (more(l->snd_nxt, l->rcv_nxt))
383 gap = l->snd_nxt - l->rcv_nxt;
384 if (skb)
385 gap = buf_seqno(skb) - l->rcv_nxt;
386 return gap;
387 }
388
389 void tipc_link_set_mtu(struct tipc_link *l, int mtu)
390 {
391 l->mtu = mtu;
392 }
393
394 int tipc_link_mtu(struct tipc_link *l)
395 {
396 return l->mtu;
397 }
398
399 u16 tipc_link_rcv_nxt(struct tipc_link *l)
400 {
401 return l->rcv_nxt;
402 }
403
404 u16 tipc_link_acked(struct tipc_link *l)
405 {
406 return l->acked;
407 }
408
409 char *tipc_link_name(struct tipc_link *l)
410 {
411 return l->name;
412 }
413
414 u32 tipc_link_state(struct tipc_link *l)
415 {
416 return l->state;
417 }
418
419 /**
420 * tipc_link_create - create a new link
421 * @n: pointer to associated node
422 * @if_name: associated interface name
423 * @bearer_id: id (index) of associated bearer
424 * @tolerance: link tolerance to be used by link
425 * @net_plane: network plane (A,B,c..) this link belongs to
426 * @mtu: mtu to be advertised by link
427 * @priority: priority to be used by link
428 * @window: send window to be used by link
429 * @session: session to be used by link
430 * @ownnode: identity of own node
431 * @peer: node id of peer node
432 * @peer_caps: bitmap describing peer node capabilities
433 * @bc_sndlink: the namespace global link used for broadcast sending
434 * @bc_rcvlink: the peer specific link used for broadcast reception
435 * @inputq: queue to put messages ready for delivery
436 * @namedq: queue to put binding table update messages ready for delivery
437 * @link: return value, pointer to put the created link
438 *
439 * Returns true if link was created, otherwise false
440 */
441 bool tipc_link_create(struct net *net, char *if_name, int bearer_id,
442 int tolerance, char net_plane, u32 mtu, int priority,
443 int window, u32 session, u32 self,
444 u32 peer, u8 *peer_id, u16 peer_caps,
445 struct tipc_link *bc_sndlink,
446 struct tipc_link *bc_rcvlink,
447 struct sk_buff_head *inputq,
448 struct sk_buff_head *namedq,
449 struct tipc_link **link)
450 {
451 char peer_str[NODE_ID_STR_LEN] = {0,};
452 char self_str[NODE_ID_STR_LEN] = {0,};
453 struct tipc_link *l;
454
455 l = kzalloc(sizeof(*l), GFP_ATOMIC);
456 if (!l)
457 return false;
458 *link = l;
459 l->session = session;
460
461 /* Set link name for unicast links only */
462 if (peer_id) {
463 tipc_nodeid2string(self_str, tipc_own_id(net));
464 if (strlen(self_str) > 16)
465 sprintf(self_str, "%x", self);
466 tipc_nodeid2string(peer_str, peer_id);
467 if (strlen(peer_str) > 16)
468 sprintf(peer_str, "%x", peer);
469 }
470 /* Peer i/f name will be completed by reset/activate message */
471 snprintf(l->name, sizeof(l->name), "%s:%s-%s:unknown",
472 self_str, if_name, peer_str);
473
474 strcpy(l->if_name, if_name);
475 l->addr = peer;
476 l->peer_caps = peer_caps;
477 l->net = net;
478 l->in_session = false;
479 l->bearer_id = bearer_id;
480 l->tolerance = tolerance;
481 if (bc_rcvlink)
482 bc_rcvlink->tolerance = tolerance;
483 l->net_plane = net_plane;
484 l->advertised_mtu = mtu;
485 l->mtu = mtu;
486 l->priority = priority;
487 tipc_link_set_queue_limits(l, window);
488 l->ackers = 1;
489 l->bc_sndlink = bc_sndlink;
490 l->bc_rcvlink = bc_rcvlink;
491 l->inputq = inputq;
492 l->namedq = namedq;
493 l->state = LINK_RESETTING;
494 __skb_queue_head_init(&l->transmq);
495 __skb_queue_head_init(&l->backlogq);
496 __skb_queue_head_init(&l->deferdq);
497 skb_queue_head_init(&l->wakeupq);
498 skb_queue_head_init(l->inputq);
499 return true;
500 }
501
502 /**
503 * tipc_link_bc_create - create new link to be used for broadcast
504 * @n: pointer to associated node
505 * @mtu: mtu to be used initially if no peers
506 * @window: send window to be used
507 * @inputq: queue to put messages ready for delivery
508 * @namedq: queue to put binding table update messages ready for delivery
509 * @link: return value, pointer to put the created link
510 *
511 * Returns true if link was created, otherwise false
512 */
513 bool tipc_link_bc_create(struct net *net, u32 ownnode, u32 peer,
514 int mtu, int window, u16 peer_caps,
515 struct sk_buff_head *inputq,
516 struct sk_buff_head *namedq,
517 struct tipc_link *bc_sndlink,
518 struct tipc_link **link)
519 {
520 struct tipc_link *l;
521
522 if (!tipc_link_create(net, "", MAX_BEARERS, 0, 'Z', mtu, 0, window,
523 0, ownnode, peer, NULL, peer_caps, bc_sndlink,
524 NULL, inputq, namedq, link))
525 return false;
526
527 l = *link;
528 strcpy(l->name, tipc_bclink_name);
529 tipc_link_reset(l);
530 l->state = LINK_RESET;
531 l->ackers = 0;
532 l->bc_rcvlink = l;
533
534 /* Broadcast send link is always up */
535 if (link_is_bc_sndlink(l))
536 l->state = LINK_ESTABLISHED;
537
538 /* Disable replicast if even a single peer doesn't support it */
539 if (link_is_bc_rcvlink(l) && !(peer_caps & TIPC_BCAST_RCAST))
540 tipc_bcast_disable_rcast(net);
541
542 return true;
543 }
544
545 /**
546 * tipc_link_fsm_evt - link finite state machine
547 * @l: pointer to link
548 * @evt: state machine event to be processed
549 */
550 int tipc_link_fsm_evt(struct tipc_link *l, int evt)
551 {
552 int rc = 0;
553
554 switch (l->state) {
555 case LINK_RESETTING:
556 switch (evt) {
557 case LINK_PEER_RESET_EVT:
558 l->state = LINK_PEER_RESET;
559 break;
560 case LINK_RESET_EVT:
561 l->state = LINK_RESET;
562 break;
563 case LINK_FAILURE_EVT:
564 case LINK_FAILOVER_BEGIN_EVT:
565 case LINK_ESTABLISH_EVT:
566 case LINK_FAILOVER_END_EVT:
567 case LINK_SYNCH_BEGIN_EVT:
568 case LINK_SYNCH_END_EVT:
569 default:
570 goto illegal_evt;
571 }
572 break;
573 case LINK_RESET:
574 switch (evt) {
575 case LINK_PEER_RESET_EVT:
576 l->state = LINK_ESTABLISHING;
577 break;
578 case LINK_FAILOVER_BEGIN_EVT:
579 l->state = LINK_FAILINGOVER;
580 case LINK_FAILURE_EVT:
581 case LINK_RESET_EVT:
582 case LINK_ESTABLISH_EVT:
583 case LINK_FAILOVER_END_EVT:
584 break;
585 case LINK_SYNCH_BEGIN_EVT:
586 case LINK_SYNCH_END_EVT:
587 default:
588 goto illegal_evt;
589 }
590 break;
591 case LINK_PEER_RESET:
592 switch (evt) {
593 case LINK_RESET_EVT:
594 l->state = LINK_ESTABLISHING;
595 break;
596 case LINK_PEER_RESET_EVT:
597 case LINK_ESTABLISH_EVT:
598 case LINK_FAILURE_EVT:
599 break;
600 case LINK_SYNCH_BEGIN_EVT:
601 case LINK_SYNCH_END_EVT:
602 case LINK_FAILOVER_BEGIN_EVT:
603 case LINK_FAILOVER_END_EVT:
604 default:
605 goto illegal_evt;
606 }
607 break;
608 case LINK_FAILINGOVER:
609 switch (evt) {
610 case LINK_FAILOVER_END_EVT:
611 l->state = LINK_RESET;
612 break;
613 case LINK_PEER_RESET_EVT:
614 case LINK_RESET_EVT:
615 case LINK_ESTABLISH_EVT:
616 case LINK_FAILURE_EVT:
617 break;
618 case LINK_FAILOVER_BEGIN_EVT:
619 case LINK_SYNCH_BEGIN_EVT:
620 case LINK_SYNCH_END_EVT:
621 default:
622 goto illegal_evt;
623 }
624 break;
625 case LINK_ESTABLISHING:
626 switch (evt) {
627 case LINK_ESTABLISH_EVT:
628 l->state = LINK_ESTABLISHED;
629 break;
630 case LINK_FAILOVER_BEGIN_EVT:
631 l->state = LINK_FAILINGOVER;
632 break;
633 case LINK_RESET_EVT:
634 l->state = LINK_RESET;
635 break;
636 case LINK_FAILURE_EVT:
637 case LINK_PEER_RESET_EVT:
638 case LINK_SYNCH_BEGIN_EVT:
639 case LINK_FAILOVER_END_EVT:
640 break;
641 case LINK_SYNCH_END_EVT:
642 default:
643 goto illegal_evt;
644 }
645 break;
646 case LINK_ESTABLISHED:
647 switch (evt) {
648 case LINK_PEER_RESET_EVT:
649 l->state = LINK_PEER_RESET;
650 rc |= TIPC_LINK_DOWN_EVT;
651 break;
652 case LINK_FAILURE_EVT:
653 l->state = LINK_RESETTING;
654 rc |= TIPC_LINK_DOWN_EVT;
655 break;
656 case LINK_RESET_EVT:
657 l->state = LINK_RESET;
658 break;
659 case LINK_ESTABLISH_EVT:
660 case LINK_SYNCH_END_EVT:
661 break;
662 case LINK_SYNCH_BEGIN_EVT:
663 l->state = LINK_SYNCHING;
664 break;
665 case LINK_FAILOVER_BEGIN_EVT:
666 case LINK_FAILOVER_END_EVT:
667 default:
668 goto illegal_evt;
669 }
670 break;
671 case LINK_SYNCHING:
672 switch (evt) {
673 case LINK_PEER_RESET_EVT:
674 l->state = LINK_PEER_RESET;
675 rc |= TIPC_LINK_DOWN_EVT;
676 break;
677 case LINK_FAILURE_EVT:
678 l->state = LINK_RESETTING;
679 rc |= TIPC_LINK_DOWN_EVT;
680 break;
681 case LINK_RESET_EVT:
682 l->state = LINK_RESET;
683 break;
684 case LINK_ESTABLISH_EVT:
685 case LINK_SYNCH_BEGIN_EVT:
686 break;
687 case LINK_SYNCH_END_EVT:
688 l->state = LINK_ESTABLISHED;
689 break;
690 case LINK_FAILOVER_BEGIN_EVT:
691 case LINK_FAILOVER_END_EVT:
692 default:
693 goto illegal_evt;
694 }
695 break;
696 default:
697 pr_err("Unknown FSM state %x in %s\n", l->state, l->name);
698 }
699 return rc;
700 illegal_evt:
701 pr_err("Illegal FSM event %x in state %x on link %s\n",
702 evt, l->state, l->name);
703 return rc;
704 }
705
706 /* link_profile_stats - update statistical profiling of traffic
707 */
708 static void link_profile_stats(struct tipc_link *l)
709 {
710 struct sk_buff *skb;
711 struct tipc_msg *msg;
712 int length;
713
714 /* Update counters used in statistical profiling of send traffic */
715 l->stats.accu_queue_sz += skb_queue_len(&l->transmq);
716 l->stats.queue_sz_counts++;
717
718 skb = skb_peek(&l->transmq);
719 if (!skb)
720 return;
721 msg = buf_msg(skb);
722 length = msg_size(msg);
723
724 if (msg_user(msg) == MSG_FRAGMENTER) {
725 if (msg_type(msg) != FIRST_FRAGMENT)
726 return;
727 length = msg_size(msg_get_wrapped(msg));
728 }
729 l->stats.msg_lengths_total += length;
730 l->stats.msg_length_counts++;
731 if (length <= 64)
732 l->stats.msg_length_profile[0]++;
733 else if (length <= 256)
734 l->stats.msg_length_profile[1]++;
735 else if (length <= 1024)
736 l->stats.msg_length_profile[2]++;
737 else if (length <= 4096)
738 l->stats.msg_length_profile[3]++;
739 else if (length <= 16384)
740 l->stats.msg_length_profile[4]++;
741 else if (length <= 32768)
742 l->stats.msg_length_profile[5]++;
743 else
744 l->stats.msg_length_profile[6]++;
745 }
746
747 /* tipc_link_timeout - perform periodic task as instructed from node timeout
748 */
749 int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq)
750 {
751 int mtyp = 0;
752 int rc = 0;
753 bool state = false;
754 bool probe = false;
755 bool setup = false;
756 u16 bc_snt = l->bc_sndlink->snd_nxt - 1;
757 u16 bc_acked = l->bc_rcvlink->acked;
758 struct tipc_mon_state *mstate = &l->mon_state;
759
760 switch (l->state) {
761 case LINK_ESTABLISHED:
762 case LINK_SYNCHING:
763 mtyp = STATE_MSG;
764 link_profile_stats(l);
765 tipc_mon_get_state(l->net, l->addr, mstate, l->bearer_id);
766 if (mstate->reset || (l->silent_intv_cnt > l->abort_limit))
767 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
768 state = bc_acked != bc_snt;
769 state |= l->bc_rcvlink->rcv_unacked;
770 state |= l->rcv_unacked;
771 state |= !skb_queue_empty(&l->transmq);
772 state |= !skb_queue_empty(&l->deferdq);
773 probe = mstate->probing;
774 probe |= l->silent_intv_cnt;
775 if (probe || mstate->monitoring)
776 l->silent_intv_cnt++;
777 break;
778 case LINK_RESET:
779 setup = l->rst_cnt++ <= 4;
780 setup |= !(l->rst_cnt % 16);
781 mtyp = RESET_MSG;
782 break;
783 case LINK_ESTABLISHING:
784 setup = true;
785 mtyp = ACTIVATE_MSG;
786 break;
787 case LINK_PEER_RESET:
788 case LINK_RESETTING:
789 case LINK_FAILINGOVER:
790 break;
791 default:
792 break;
793 }
794
795 if (state || probe || setup)
796 tipc_link_build_proto_msg(l, mtyp, probe, 0, 0, 0, 0, xmitq);
797
798 return rc;
799 }
800
801 /**
802 * link_schedule_user - schedule a message sender for wakeup after congestion
803 * @l: congested link
804 * @hdr: header of message that is being sent
805 * Create pseudo msg to send back to user when congestion abates
806 */
807 static int link_schedule_user(struct tipc_link *l, struct tipc_msg *hdr)
808 {
809 u32 dnode = tipc_own_addr(l->net);
810 u32 dport = msg_origport(hdr);
811 struct sk_buff *skb;
812
813 /* Create and schedule wakeup pseudo message */
814 skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0,
815 dnode, l->addr, dport, 0, 0);
816 if (!skb)
817 return -ENOBUFS;
818 msg_set_dest_droppable(buf_msg(skb), true);
819 TIPC_SKB_CB(skb)->chain_imp = msg_importance(hdr);
820 skb_queue_tail(&l->wakeupq, skb);
821 l->stats.link_congs++;
822 return -ELINKCONG;
823 }
824
825 /**
826 * link_prepare_wakeup - prepare users for wakeup after congestion
827 * @l: congested link
828 * Wake up a number of waiting users, as permitted by available space
829 * in the send queue
830 */
831 static void link_prepare_wakeup(struct tipc_link *l)
832 {
833 struct sk_buff_head *wakeupq = &l->wakeupq;
834 struct sk_buff_head *inputq = l->inputq;
835 struct sk_buff *skb, *tmp;
836 struct sk_buff_head tmpq;
837 int avail[5] = {0,};
838 int imp = 0;
839
840 __skb_queue_head_init(&tmpq);
841
842 for (; imp <= TIPC_SYSTEM_IMPORTANCE; imp++)
843 avail[imp] = l->backlog[imp].limit - l->backlog[imp].len;
844
845 skb_queue_walk_safe(wakeupq, skb, tmp) {
846 imp = TIPC_SKB_CB(skb)->chain_imp;
847 if (avail[imp] <= 0)
848 continue;
849 avail[imp]--;
850 __skb_unlink(skb, wakeupq);
851 __skb_queue_tail(&tmpq, skb);
852 }
853
854 spin_lock_bh(&inputq->lock);
855 skb_queue_splice_tail(&tmpq, inputq);
856 spin_unlock_bh(&inputq->lock);
857
858 }
859
860 void tipc_link_reset(struct tipc_link *l)
861 {
862 struct sk_buff_head list;
863 u32 imp;
864
865 __skb_queue_head_init(&list);
866
867 l->in_session = false;
868 l->session++;
869 l->mtu = l->advertised_mtu;
870
871 spin_lock_bh(&l->wakeupq.lock);
872 skb_queue_splice_init(&l->wakeupq, &list);
873 spin_unlock_bh(&l->wakeupq.lock);
874
875 spin_lock_bh(&l->inputq->lock);
876 skb_queue_splice_init(&list, l->inputq);
877 spin_unlock_bh(&l->inputq->lock);
878
879 __skb_queue_purge(&l->transmq);
880 __skb_queue_purge(&l->deferdq);
881 __skb_queue_purge(&l->backlogq);
882 for (imp = 0; imp <= TIPC_SYSTEM_IMPORTANCE; imp++) {
883 l->backlog[imp].len = 0;
884 l->backlog[imp].target_bskb = NULL;
885 }
886 kfree_skb(l->reasm_buf);
887 kfree_skb(l->failover_reasm_skb);
888 l->reasm_buf = NULL;
889 l->failover_reasm_skb = NULL;
890 l->rcv_unacked = 0;
891 l->snd_nxt = 1;
892 l->rcv_nxt = 1;
893 l->snd_nxt_state = 1;
894 l->rcv_nxt_state = 1;
895 l->acked = 0;
896 l->silent_intv_cnt = 0;
897 l->rst_cnt = 0;
898 l->stale_cnt = 0;
899 l->bc_peer_is_up = false;
900 memset(&l->mon_state, 0, sizeof(l->mon_state));
901 tipc_link_reset_stats(l);
902 }
903
904 /**
905 * tipc_link_xmit(): enqueue buffer list according to queue situation
906 * @link: link to use
907 * @list: chain of buffers containing message
908 * @xmitq: returned list of packets to be sent by caller
909 *
910 * Consumes the buffer chain.
911 * Returns 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS
912 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted
913 */
914 int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list,
915 struct sk_buff_head *xmitq)
916 {
917 struct tipc_msg *hdr = buf_msg(skb_peek(list));
918 unsigned int maxwin = l->window;
919 int imp = msg_importance(hdr);
920 unsigned int mtu = l->mtu;
921 u16 ack = l->rcv_nxt - 1;
922 u16 seqno = l->snd_nxt;
923 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
924 struct sk_buff_head *transmq = &l->transmq;
925 struct sk_buff_head *backlogq = &l->backlogq;
926 struct sk_buff *skb, *_skb, **tskb;
927 int pkt_cnt = skb_queue_len(list);
928 int rc = 0;
929
930 if (unlikely(msg_size(hdr) > mtu)) {
931 skb_queue_purge(list);
932 return -EMSGSIZE;
933 }
934
935 /* Allow oversubscription of one data msg per source at congestion */
936 if (unlikely(l->backlog[imp].len >= l->backlog[imp].limit)) {
937 if (imp == TIPC_SYSTEM_IMPORTANCE) {
938 pr_warn("%s<%s>, link overflow", link_rst_msg, l->name);
939 return -ENOBUFS;
940 }
941 rc = link_schedule_user(l, hdr);
942 }
943
944 if (pkt_cnt > 1) {
945 l->stats.sent_fragmented++;
946 l->stats.sent_fragments += pkt_cnt;
947 }
948
949 /* Prepare each packet for sending, and add to relevant queue: */
950 while (skb_queue_len(list)) {
951 skb = skb_peek(list);
952 hdr = buf_msg(skb);
953 msg_set_seqno(hdr, seqno);
954 msg_set_ack(hdr, ack);
955 msg_set_bcast_ack(hdr, bc_ack);
956
957 if (likely(skb_queue_len(transmq) < maxwin)) {
958 _skb = skb_clone(skb, GFP_ATOMIC);
959 if (!_skb) {
960 skb_queue_purge(list);
961 return -ENOBUFS;
962 }
963 __skb_dequeue(list);
964 __skb_queue_tail(transmq, skb);
965 __skb_queue_tail(xmitq, _skb);
966 TIPC_SKB_CB(skb)->ackers = l->ackers;
967 l->rcv_unacked = 0;
968 l->stats.sent_pkts++;
969 seqno++;
970 continue;
971 }
972 tskb = &l->backlog[imp].target_bskb;
973 if (tipc_msg_bundle(*tskb, hdr, mtu)) {
974 kfree_skb(__skb_dequeue(list));
975 l->stats.sent_bundled++;
976 continue;
977 }
978 if (tipc_msg_make_bundle(tskb, hdr, mtu, l->addr)) {
979 kfree_skb(__skb_dequeue(list));
980 __skb_queue_tail(backlogq, *tskb);
981 l->backlog[imp].len++;
982 l->stats.sent_bundled++;
983 l->stats.sent_bundles++;
984 continue;
985 }
986 l->backlog[imp].target_bskb = NULL;
987 l->backlog[imp].len += skb_queue_len(list);
988 skb_queue_splice_tail_init(list, backlogq);
989 }
990 l->snd_nxt = seqno;
991 return rc;
992 }
993
994 static void tipc_link_advance_backlog(struct tipc_link *l,
995 struct sk_buff_head *xmitq)
996 {
997 struct sk_buff *skb, *_skb;
998 struct tipc_msg *hdr;
999 u16 seqno = l->snd_nxt;
1000 u16 ack = l->rcv_nxt - 1;
1001 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1002 u32 imp;
1003
1004 while (skb_queue_len(&l->transmq) < l->window) {
1005 skb = skb_peek(&l->backlogq);
1006 if (!skb)
1007 break;
1008 _skb = skb_clone(skb, GFP_ATOMIC);
1009 if (!_skb)
1010 break;
1011 __skb_dequeue(&l->backlogq);
1012 hdr = buf_msg(skb);
1013 imp = msg_importance(hdr);
1014 l->backlog[imp].len--;
1015 if (unlikely(skb == l->backlog[imp].target_bskb))
1016 l->backlog[imp].target_bskb = NULL;
1017 __skb_queue_tail(&l->transmq, skb);
1018 __skb_queue_tail(xmitq, _skb);
1019 TIPC_SKB_CB(skb)->ackers = l->ackers;
1020 msg_set_seqno(hdr, seqno);
1021 msg_set_ack(hdr, ack);
1022 msg_set_bcast_ack(hdr, bc_ack);
1023 l->rcv_unacked = 0;
1024 l->stats.sent_pkts++;
1025 seqno++;
1026 }
1027 l->snd_nxt = seqno;
1028 }
1029
1030 static void link_retransmit_failure(struct tipc_link *l, struct sk_buff *skb)
1031 {
1032 struct tipc_msg *hdr = buf_msg(skb);
1033
1034 pr_warn("Retransmission failure on link <%s>\n", l->name);
1035 link_print(l, "State of link ");
1036 pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n",
1037 msg_user(hdr), msg_type(hdr), msg_size(hdr), msg_errcode(hdr));
1038 pr_info("sqno %u, prev: %x, src: %x\n",
1039 msg_seqno(hdr), msg_prevnode(hdr), msg_orignode(hdr));
1040 }
1041
1042 /* tipc_link_retrans() - retransmit one or more packets
1043 * @l: the link to transmit on
1044 * @r: the receiving link ordering the retransmit. Same as l if unicast
1045 * @from: retransmit from (inclusive) this sequence number
1046 * @to: retransmit to (inclusive) this sequence number
1047 * xmitq: queue for accumulating the retransmitted packets
1048 */
1049 static int tipc_link_retrans(struct tipc_link *l, struct tipc_link *r,
1050 u16 from, u16 to, struct sk_buff_head *xmitq)
1051 {
1052 struct sk_buff *_skb, *skb = skb_peek(&l->transmq);
1053 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1054 u16 ack = l->rcv_nxt - 1;
1055 struct tipc_msg *hdr;
1056
1057 if (!skb)
1058 return 0;
1059
1060 /* Detect repeated retransmit failures on same packet */
1061 if (r->last_retransm != buf_seqno(skb)) {
1062 r->last_retransm = buf_seqno(skb);
1063 r->stale_limit = jiffies + msecs_to_jiffies(r->tolerance);
1064 r->stale_cnt = 0;
1065 } else if (++r->stale_cnt > 99 && time_after(jiffies, r->stale_limit)) {
1066 link_retransmit_failure(l, skb);
1067 if (link_is_bc_sndlink(l))
1068 return TIPC_LINK_DOWN_EVT;
1069 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1070 }
1071
1072 skb_queue_walk(&l->transmq, skb) {
1073 hdr = buf_msg(skb);
1074 if (less(msg_seqno(hdr), from))
1075 continue;
1076 if (more(msg_seqno(hdr), to))
1077 break;
1078 _skb = __pskb_copy(skb, MIN_H_SIZE, GFP_ATOMIC);
1079 if (!_skb)
1080 return 0;
1081 hdr = buf_msg(_skb);
1082 msg_set_ack(hdr, ack);
1083 msg_set_bcast_ack(hdr, bc_ack);
1084 _skb->priority = TC_PRIO_CONTROL;
1085 __skb_queue_tail(xmitq, _skb);
1086 l->stats.retransmitted++;
1087 }
1088 return 0;
1089 }
1090
1091 /* tipc_data_input - deliver data and name distr msgs to upper layer
1092 *
1093 * Consumes buffer if message is of right type
1094 * Node lock must be held
1095 */
1096 static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb,
1097 struct sk_buff_head *inputq)
1098 {
1099 struct sk_buff_head *mc_inputq = l->bc_rcvlink->inputq;
1100 struct tipc_msg *hdr = buf_msg(skb);
1101
1102 switch (msg_user(hdr)) {
1103 case TIPC_LOW_IMPORTANCE:
1104 case TIPC_MEDIUM_IMPORTANCE:
1105 case TIPC_HIGH_IMPORTANCE:
1106 case TIPC_CRITICAL_IMPORTANCE:
1107 if (unlikely(msg_in_group(hdr) || msg_mcast(hdr))) {
1108 skb_queue_tail(mc_inputq, skb);
1109 return true;
1110 }
1111 /* else: fall through */
1112 case CONN_MANAGER:
1113 skb_queue_tail(inputq, skb);
1114 return true;
1115 case GROUP_PROTOCOL:
1116 skb_queue_tail(mc_inputq, skb);
1117 return true;
1118 case NAME_DISTRIBUTOR:
1119 l->bc_rcvlink->state = LINK_ESTABLISHED;
1120 skb_queue_tail(l->namedq, skb);
1121 return true;
1122 case MSG_BUNDLER:
1123 case TUNNEL_PROTOCOL:
1124 case MSG_FRAGMENTER:
1125 case BCAST_PROTOCOL:
1126 return false;
1127 default:
1128 pr_warn("Dropping received illegal msg type\n");
1129 kfree_skb(skb);
1130 return true;
1131 };
1132 }
1133
1134 /* tipc_link_input - process packet that has passed link protocol check
1135 *
1136 * Consumes buffer
1137 */
1138 static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb,
1139 struct sk_buff_head *inputq)
1140 {
1141 struct tipc_msg *hdr = buf_msg(skb);
1142 struct sk_buff **reasm_skb = &l->reasm_buf;
1143 struct sk_buff *iskb;
1144 struct sk_buff_head tmpq;
1145 int usr = msg_user(hdr);
1146 int rc = 0;
1147 int pos = 0;
1148 int ipos = 0;
1149
1150 if (unlikely(usr == TUNNEL_PROTOCOL)) {
1151 if (msg_type(hdr) == SYNCH_MSG) {
1152 __skb_queue_purge(&l->deferdq);
1153 goto drop;
1154 }
1155 if (!tipc_msg_extract(skb, &iskb, &ipos))
1156 return rc;
1157 kfree_skb(skb);
1158 skb = iskb;
1159 hdr = buf_msg(skb);
1160 if (less(msg_seqno(hdr), l->drop_point))
1161 goto drop;
1162 if (tipc_data_input(l, skb, inputq))
1163 return rc;
1164 usr = msg_user(hdr);
1165 reasm_skb = &l->failover_reasm_skb;
1166 }
1167
1168 if (usr == MSG_BUNDLER) {
1169 skb_queue_head_init(&tmpq);
1170 l->stats.recv_bundles++;
1171 l->stats.recv_bundled += msg_msgcnt(hdr);
1172 while (tipc_msg_extract(skb, &iskb, &pos))
1173 tipc_data_input(l, iskb, &tmpq);
1174 tipc_skb_queue_splice_tail(&tmpq, inputq);
1175 return 0;
1176 } else if (usr == MSG_FRAGMENTER) {
1177 l->stats.recv_fragments++;
1178 if (tipc_buf_append(reasm_skb, &skb)) {
1179 l->stats.recv_fragmented++;
1180 tipc_data_input(l, skb, inputq);
1181 } else if (!*reasm_skb && !link_is_bc_rcvlink(l)) {
1182 pr_warn_ratelimited("Unable to build fragment list\n");
1183 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1184 }
1185 return 0;
1186 } else if (usr == BCAST_PROTOCOL) {
1187 tipc_bcast_lock(l->net);
1188 tipc_link_bc_init_rcv(l->bc_rcvlink, hdr);
1189 tipc_bcast_unlock(l->net);
1190 }
1191 drop:
1192 kfree_skb(skb);
1193 return 0;
1194 }
1195
1196 static bool tipc_link_release_pkts(struct tipc_link *l, u16 acked)
1197 {
1198 bool released = false;
1199 struct sk_buff *skb, *tmp;
1200
1201 skb_queue_walk_safe(&l->transmq, skb, tmp) {
1202 if (more(buf_seqno(skb), acked))
1203 break;
1204 __skb_unlink(skb, &l->transmq);
1205 kfree_skb(skb);
1206 released = true;
1207 }
1208 return released;
1209 }
1210
1211 /* tipc_link_build_state_msg: prepare link state message for transmission
1212 *
1213 * Note that sending of broadcast ack is coordinated among nodes, to reduce
1214 * risk of ack storms towards the sender
1215 */
1216 int tipc_link_build_state_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1217 {
1218 if (!l)
1219 return 0;
1220
1221 /* Broadcast ACK must be sent via a unicast link => defer to caller */
1222 if (link_is_bc_rcvlink(l)) {
1223 if (((l->rcv_nxt ^ tipc_own_addr(l->net)) & 0xf) != 0xf)
1224 return 0;
1225 l->rcv_unacked = 0;
1226
1227 /* Use snd_nxt to store peer's snd_nxt in broadcast rcv link */
1228 l->snd_nxt = l->rcv_nxt;
1229 return TIPC_LINK_SND_STATE;
1230 }
1231
1232 /* Unicast ACK */
1233 l->rcv_unacked = 0;
1234 l->stats.sent_acks++;
1235 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, 0, xmitq);
1236 return 0;
1237 }
1238
1239 /* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message
1240 */
1241 void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1242 {
1243 int mtyp = RESET_MSG;
1244 struct sk_buff *skb;
1245
1246 if (l->state == LINK_ESTABLISHING)
1247 mtyp = ACTIVATE_MSG;
1248
1249 tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, 0, xmitq);
1250
1251 /* Inform peer that this endpoint is going down if applicable */
1252 skb = skb_peek_tail(xmitq);
1253 if (skb && (l->state == LINK_RESET))
1254 msg_set_peer_stopping(buf_msg(skb), 1);
1255 }
1256
1257 /* tipc_link_build_nack_msg: prepare link nack message for transmission
1258 * Note that sending of broadcast NACK is coordinated among nodes, to
1259 * reduce the risk of NACK storms towards the sender
1260 */
1261 static int tipc_link_build_nack_msg(struct tipc_link *l,
1262 struct sk_buff_head *xmitq)
1263 {
1264 u32 def_cnt = ++l->stats.deferred_recv;
1265 int match1, match2;
1266
1267 if (link_is_bc_rcvlink(l)) {
1268 match1 = def_cnt & 0xf;
1269 match2 = tipc_own_addr(l->net) & 0xf;
1270 if (match1 == match2)
1271 return TIPC_LINK_SND_STATE;
1272 return 0;
1273 }
1274
1275 if ((skb_queue_len(&l->deferdq) == 1) || !(def_cnt % TIPC_NACK_INTV))
1276 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, 0, xmitq);
1277 return 0;
1278 }
1279
1280 /* tipc_link_rcv - process TIPC packets/messages arriving from off-node
1281 * @l: the link that should handle the message
1282 * @skb: TIPC packet
1283 * @xmitq: queue to place packets to be sent after this call
1284 */
1285 int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb,
1286 struct sk_buff_head *xmitq)
1287 {
1288 struct sk_buff_head *defq = &l->deferdq;
1289 struct tipc_msg *hdr;
1290 u16 seqno, rcv_nxt, win_lim;
1291 int rc = 0;
1292
1293 do {
1294 hdr = buf_msg(skb);
1295 seqno = msg_seqno(hdr);
1296 rcv_nxt = l->rcv_nxt;
1297 win_lim = rcv_nxt + TIPC_MAX_LINK_WIN;
1298
1299 /* Verify and update link state */
1300 if (unlikely(msg_user(hdr) == LINK_PROTOCOL))
1301 return tipc_link_proto_rcv(l, skb, xmitq);
1302
1303 if (unlikely(!link_is_up(l))) {
1304 if (l->state == LINK_ESTABLISHING)
1305 rc = TIPC_LINK_UP_EVT;
1306 goto drop;
1307 }
1308
1309 /* Don't send probe at next timeout expiration */
1310 l->silent_intv_cnt = 0;
1311
1312 /* Drop if outside receive window */
1313 if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) {
1314 l->stats.duplicates++;
1315 goto drop;
1316 }
1317
1318 /* Forward queues and wake up waiting users */
1319 if (likely(tipc_link_release_pkts(l, msg_ack(hdr)))) {
1320 l->stale_cnt = 0;
1321 tipc_link_advance_backlog(l, xmitq);
1322 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1323 link_prepare_wakeup(l);
1324 }
1325
1326 /* Defer delivery if sequence gap */
1327 if (unlikely(seqno != rcv_nxt)) {
1328 __tipc_skb_queue_sorted(defq, seqno, skb);
1329 rc |= tipc_link_build_nack_msg(l, xmitq);
1330 break;
1331 }
1332
1333 /* Deliver packet */
1334 l->rcv_nxt++;
1335 l->stats.recv_pkts++;
1336 if (!tipc_data_input(l, skb, l->inputq))
1337 rc |= tipc_link_input(l, skb, l->inputq);
1338 if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN))
1339 rc |= tipc_link_build_state_msg(l, xmitq);
1340 if (unlikely(rc & ~TIPC_LINK_SND_STATE))
1341 break;
1342 } while ((skb = __skb_dequeue(defq)));
1343
1344 return rc;
1345 drop:
1346 kfree_skb(skb);
1347 return rc;
1348 }
1349
1350 static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
1351 bool probe_reply, u16 rcvgap,
1352 int tolerance, int priority,
1353 struct sk_buff_head *xmitq)
1354 {
1355 struct tipc_link *bcl = l->bc_rcvlink;
1356 struct sk_buff *skb;
1357 struct tipc_msg *hdr;
1358 struct sk_buff_head *dfq = &l->deferdq;
1359 bool node_up = link_is_up(bcl);
1360 struct tipc_mon_state *mstate = &l->mon_state;
1361 int dlen = 0;
1362 void *data;
1363
1364 /* Don't send protocol message during reset or link failover */
1365 if (tipc_link_is_blocked(l))
1366 return;
1367
1368 if (!tipc_link_is_up(l) && (mtyp == STATE_MSG))
1369 return;
1370
1371 if (!skb_queue_empty(dfq))
1372 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1373
1374 skb = tipc_msg_create(LINK_PROTOCOL, mtyp, INT_H_SIZE,
1375 tipc_max_domain_size, l->addr,
1376 tipc_own_addr(l->net), 0, 0, 0);
1377 if (!skb)
1378 return;
1379
1380 hdr = buf_msg(skb);
1381 data = msg_data(hdr);
1382 msg_set_session(hdr, l->session);
1383 msg_set_bearer_id(hdr, l->bearer_id);
1384 msg_set_net_plane(hdr, l->net_plane);
1385 msg_set_next_sent(hdr, l->snd_nxt);
1386 msg_set_ack(hdr, l->rcv_nxt - 1);
1387 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
1388 msg_set_bc_ack_invalid(hdr, !node_up);
1389 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
1390 msg_set_link_tolerance(hdr, tolerance);
1391 msg_set_linkprio(hdr, priority);
1392 msg_set_redundant_link(hdr, node_up);
1393 msg_set_seq_gap(hdr, 0);
1394 msg_set_seqno(hdr, l->snd_nxt + U16_MAX / 2);
1395
1396 if (mtyp == STATE_MSG) {
1397 if (l->peer_caps & TIPC_LINK_PROTO_SEQNO)
1398 msg_set_seqno(hdr, l->snd_nxt_state++);
1399 msg_set_seq_gap(hdr, rcvgap);
1400 msg_set_bc_gap(hdr, link_bc_rcv_gap(bcl));
1401 msg_set_probe(hdr, probe);
1402 msg_set_is_keepalive(hdr, probe || probe_reply);
1403 tipc_mon_prep(l->net, data, &dlen, mstate, l->bearer_id);
1404 msg_set_size(hdr, INT_H_SIZE + dlen);
1405 skb_trim(skb, INT_H_SIZE + dlen);
1406 l->stats.sent_states++;
1407 l->rcv_unacked = 0;
1408 } else {
1409 /* RESET_MSG or ACTIVATE_MSG */
1410 msg_set_max_pkt(hdr, l->advertised_mtu);
1411 strcpy(data, l->if_name);
1412 msg_set_size(hdr, INT_H_SIZE + TIPC_MAX_IF_NAME);
1413 skb_trim(skb, INT_H_SIZE + TIPC_MAX_IF_NAME);
1414 }
1415 if (probe)
1416 l->stats.sent_probes++;
1417 if (rcvgap)
1418 l->stats.sent_nacks++;
1419 skb->priority = TC_PRIO_CONTROL;
1420 __skb_queue_tail(xmitq, skb);
1421 }
1422
1423 void tipc_link_create_dummy_tnl_msg(struct tipc_link *l,
1424 struct sk_buff_head *xmitq)
1425 {
1426 u32 onode = tipc_own_addr(l->net);
1427 struct tipc_msg *hdr, *ihdr;
1428 struct sk_buff_head tnlq;
1429 struct sk_buff *skb;
1430 u32 dnode = l->addr;
1431
1432 skb_queue_head_init(&tnlq);
1433 skb = tipc_msg_create(TUNNEL_PROTOCOL, FAILOVER_MSG,
1434 INT_H_SIZE, BASIC_H_SIZE,
1435 dnode, onode, 0, 0, 0);
1436 if (!skb) {
1437 pr_warn("%sunable to create tunnel packet\n", link_co_err);
1438 return;
1439 }
1440
1441 hdr = buf_msg(skb);
1442 msg_set_msgcnt(hdr, 1);
1443 msg_set_bearer_id(hdr, l->peer_bearer_id);
1444
1445 ihdr = (struct tipc_msg *)msg_data(hdr);
1446 tipc_msg_init(onode, ihdr, TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1447 BASIC_H_SIZE, dnode);
1448 msg_set_errcode(ihdr, TIPC_ERR_NO_PORT);
1449 __skb_queue_tail(&tnlq, skb);
1450 tipc_link_xmit(l, &tnlq, xmitq);
1451 }
1452
1453 /* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets
1454 * with contents of the link's transmit and backlog queues.
1455 */
1456 void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
1457 int mtyp, struct sk_buff_head *xmitq)
1458 {
1459 struct sk_buff *skb, *tnlskb;
1460 struct tipc_msg *hdr, tnlhdr;
1461 struct sk_buff_head *queue = &l->transmq;
1462 struct sk_buff_head tmpxq, tnlq;
1463 u16 pktlen, pktcnt, seqno = l->snd_nxt;
1464
1465 if (!tnl)
1466 return;
1467
1468 skb_queue_head_init(&tnlq);
1469 skb_queue_head_init(&tmpxq);
1470
1471 /* At least one packet required for safe algorithm => add dummy */
1472 skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1473 BASIC_H_SIZE, 0, l->addr, tipc_own_addr(l->net),
1474 0, 0, TIPC_ERR_NO_PORT);
1475 if (!skb) {
1476 pr_warn("%sunable to create tunnel packet\n", link_co_err);
1477 return;
1478 }
1479 skb_queue_tail(&tnlq, skb);
1480 tipc_link_xmit(l, &tnlq, &tmpxq);
1481 __skb_queue_purge(&tmpxq);
1482
1483 /* Initialize reusable tunnel packet header */
1484 tipc_msg_init(tipc_own_addr(l->net), &tnlhdr, TUNNEL_PROTOCOL,
1485 mtyp, INT_H_SIZE, l->addr);
1486 pktcnt = skb_queue_len(&l->transmq) + skb_queue_len(&l->backlogq);
1487 msg_set_msgcnt(&tnlhdr, pktcnt);
1488 msg_set_bearer_id(&tnlhdr, l->peer_bearer_id);
1489 tnl:
1490 /* Wrap each packet into a tunnel packet */
1491 skb_queue_walk(queue, skb) {
1492 hdr = buf_msg(skb);
1493 if (queue == &l->backlogq)
1494 msg_set_seqno(hdr, seqno++);
1495 pktlen = msg_size(hdr);
1496 msg_set_size(&tnlhdr, pktlen + INT_H_SIZE);
1497 tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE, GFP_ATOMIC);
1498 if (!tnlskb) {
1499 pr_warn("%sunable to send packet\n", link_co_err);
1500 return;
1501 }
1502 skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE);
1503 skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen);
1504 __skb_queue_tail(&tnlq, tnlskb);
1505 }
1506 if (queue != &l->backlogq) {
1507 queue = &l->backlogq;
1508 goto tnl;
1509 }
1510
1511 tipc_link_xmit(tnl, &tnlq, xmitq);
1512
1513 if (mtyp == FAILOVER_MSG) {
1514 tnl->drop_point = l->rcv_nxt;
1515 tnl->failover_reasm_skb = l->reasm_buf;
1516 l->reasm_buf = NULL;
1517 }
1518 }
1519
1520 /* tipc_link_validate_msg(): validate message against current link state
1521 * Returns true if message should be accepted, otherwise false
1522 */
1523 bool tipc_link_validate_msg(struct tipc_link *l, struct tipc_msg *hdr)
1524 {
1525 u16 curr_session = l->peer_session;
1526 u16 session = msg_session(hdr);
1527 int mtyp = msg_type(hdr);
1528
1529 if (msg_user(hdr) != LINK_PROTOCOL)
1530 return true;
1531
1532 switch (mtyp) {
1533 case RESET_MSG:
1534 if (!l->in_session)
1535 return true;
1536 /* Accept only RESET with new session number */
1537 return more(session, curr_session);
1538 case ACTIVATE_MSG:
1539 if (!l->in_session)
1540 return true;
1541 /* Accept only ACTIVATE with new or current session number */
1542 return !less(session, curr_session);
1543 case STATE_MSG:
1544 /* Accept only STATE with current session number */
1545 if (!l->in_session)
1546 return false;
1547 if (session != curr_session)
1548 return false;
1549 /* Extra sanity check */
1550 if (!link_is_up(l) && msg_ack(hdr))
1551 return false;
1552 if (!(l->peer_caps & TIPC_LINK_PROTO_SEQNO))
1553 return true;
1554 /* Accept only STATE with new sequence number */
1555 return !less(msg_seqno(hdr), l->rcv_nxt_state);
1556 default:
1557 return false;
1558 }
1559 }
1560
1561 /* tipc_link_proto_rcv(): receive link level protocol message :
1562 * Note that network plane id propagates through the network, and may
1563 * change at any time. The node with lowest numerical id determines
1564 * network plane
1565 */
1566 static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
1567 struct sk_buff_head *xmitq)
1568 {
1569 struct tipc_msg *hdr = buf_msg(skb);
1570 u16 rcvgap = 0;
1571 u16 ack = msg_ack(hdr);
1572 u16 gap = msg_seq_gap(hdr);
1573 u16 peers_snd_nxt = msg_next_sent(hdr);
1574 u16 peers_tol = msg_link_tolerance(hdr);
1575 u16 peers_prio = msg_linkprio(hdr);
1576 u16 rcv_nxt = l->rcv_nxt;
1577 u16 dlen = msg_data_sz(hdr);
1578 int mtyp = msg_type(hdr);
1579 bool reply = msg_probe(hdr);
1580 void *data;
1581 char *if_name;
1582 int rc = 0;
1583
1584 if (tipc_link_is_blocked(l) || !xmitq)
1585 goto exit;
1586
1587 if (tipc_own_addr(l->net) > msg_prevnode(hdr))
1588 l->net_plane = msg_net_plane(hdr);
1589
1590 skb_linearize(skb);
1591 hdr = buf_msg(skb);
1592 data = msg_data(hdr);
1593
1594 if (!tipc_link_validate_msg(l, hdr))
1595 goto exit;
1596
1597 switch (mtyp) {
1598 case RESET_MSG:
1599 case ACTIVATE_MSG:
1600 /* Complete own link name with peer's interface name */
1601 if_name = strrchr(l->name, ':') + 1;
1602 if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME)
1603 break;
1604 if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME)
1605 break;
1606 strncpy(if_name, data, TIPC_MAX_IF_NAME);
1607
1608 /* Update own tolerance if peer indicates a non-zero value */
1609 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
1610 l->tolerance = peers_tol;
1611 l->bc_rcvlink->tolerance = peers_tol;
1612 }
1613 /* Update own priority if peer's priority is higher */
1614 if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
1615 l->priority = peers_prio;
1616
1617 /* If peer is going down we want full re-establish cycle */
1618 if (msg_peer_stopping(hdr)) {
1619 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1620 break;
1621 }
1622 /* ACTIVATE_MSG serves as PEER_RESET if link is already down */
1623 if (mtyp == RESET_MSG || !link_is_up(l))
1624 rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT);
1625
1626 /* ACTIVATE_MSG takes up link if it was already locally reset */
1627 if (mtyp == ACTIVATE_MSG && l->state == LINK_ESTABLISHING)
1628 rc = TIPC_LINK_UP_EVT;
1629
1630 l->peer_session = msg_session(hdr);
1631 l->in_session = true;
1632 l->peer_bearer_id = msg_bearer_id(hdr);
1633 if (l->mtu > msg_max_pkt(hdr))
1634 l->mtu = msg_max_pkt(hdr);
1635 break;
1636
1637 case STATE_MSG:
1638 l->rcv_nxt_state = msg_seqno(hdr) + 1;
1639
1640 /* Update own tolerance if peer indicates a non-zero value */
1641 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
1642 l->tolerance = peers_tol;
1643 l->bc_rcvlink->tolerance = peers_tol;
1644 }
1645 /* Update own prio if peer indicates a different value */
1646 if ((peers_prio != l->priority) &&
1647 in_range(peers_prio, 1, TIPC_MAX_LINK_PRI)) {
1648 l->priority = peers_prio;
1649 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1650 }
1651
1652 l->silent_intv_cnt = 0;
1653 l->stats.recv_states++;
1654 if (msg_probe(hdr))
1655 l->stats.recv_probes++;
1656
1657 if (!link_is_up(l)) {
1658 if (l->state == LINK_ESTABLISHING)
1659 rc = TIPC_LINK_UP_EVT;
1660 break;
1661 }
1662 tipc_mon_rcv(l->net, data, dlen, l->addr,
1663 &l->mon_state, l->bearer_id);
1664
1665 /* Send NACK if peer has sent pkts we haven't received yet */
1666 if (more(peers_snd_nxt, rcv_nxt) && !tipc_link_is_synching(l))
1667 rcvgap = peers_snd_nxt - l->rcv_nxt;
1668 if (rcvgap || reply)
1669 tipc_link_build_proto_msg(l, STATE_MSG, 0, reply,
1670 rcvgap, 0, 0, xmitq);
1671 tipc_link_release_pkts(l, ack);
1672
1673 /* If NACK, retransmit will now start at right position */
1674 if (gap) {
1675 rc = tipc_link_retrans(l, l, ack + 1, ack + gap, xmitq);
1676 l->stats.recv_nacks++;
1677 }
1678
1679 tipc_link_advance_backlog(l, xmitq);
1680 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1681 link_prepare_wakeup(l);
1682 }
1683 exit:
1684 kfree_skb(skb);
1685 return rc;
1686 }
1687
1688 /* tipc_link_build_bc_proto_msg() - create broadcast protocol message
1689 */
1690 static bool tipc_link_build_bc_proto_msg(struct tipc_link *l, bool bcast,
1691 u16 peers_snd_nxt,
1692 struct sk_buff_head *xmitq)
1693 {
1694 struct sk_buff *skb;
1695 struct tipc_msg *hdr;
1696 struct sk_buff *dfrd_skb = skb_peek(&l->deferdq);
1697 u16 ack = l->rcv_nxt - 1;
1698 u16 gap_to = peers_snd_nxt - 1;
1699
1700 skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE,
1701 0, l->addr, tipc_own_addr(l->net), 0, 0, 0);
1702 if (!skb)
1703 return false;
1704 hdr = buf_msg(skb);
1705 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
1706 msg_set_bcast_ack(hdr, ack);
1707 msg_set_bcgap_after(hdr, ack);
1708 if (dfrd_skb)
1709 gap_to = buf_seqno(dfrd_skb) - 1;
1710 msg_set_bcgap_to(hdr, gap_to);
1711 msg_set_non_seq(hdr, bcast);
1712 __skb_queue_tail(xmitq, skb);
1713 return true;
1714 }
1715
1716 /* tipc_link_build_bc_init_msg() - synchronize broadcast link endpoints.
1717 *
1718 * Give a newly added peer node the sequence number where it should
1719 * start receiving and acking broadcast packets.
1720 */
1721 static void tipc_link_build_bc_init_msg(struct tipc_link *l,
1722 struct sk_buff_head *xmitq)
1723 {
1724 struct sk_buff_head list;
1725
1726 __skb_queue_head_init(&list);
1727 if (!tipc_link_build_bc_proto_msg(l->bc_rcvlink, false, 0, &list))
1728 return;
1729 msg_set_bc_ack_invalid(buf_msg(skb_peek(&list)), true);
1730 tipc_link_xmit(l, &list, xmitq);
1731 }
1732
1733 /* tipc_link_bc_init_rcv - receive initial broadcast synch data from peer
1734 */
1735 void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr)
1736 {
1737 int mtyp = msg_type(hdr);
1738 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
1739
1740 if (link_is_up(l))
1741 return;
1742
1743 if (msg_user(hdr) == BCAST_PROTOCOL) {
1744 l->rcv_nxt = peers_snd_nxt;
1745 l->state = LINK_ESTABLISHED;
1746 return;
1747 }
1748
1749 if (l->peer_caps & TIPC_BCAST_SYNCH)
1750 return;
1751
1752 if (msg_peer_node_is_up(hdr))
1753 return;
1754
1755 /* Compatibility: accept older, less safe initial synch data */
1756 if ((mtyp == RESET_MSG) || (mtyp == ACTIVATE_MSG))
1757 l->rcv_nxt = peers_snd_nxt;
1758 }
1759
1760 /* link_bc_retr eval()- check if the indicated range can be retransmitted now
1761 * - Adjust permitted range if there is overlap with previous retransmission
1762 */
1763 static bool link_bc_retr_eval(struct tipc_link *l, u16 *from, u16 *to)
1764 {
1765 unsigned long elapsed = jiffies_to_msecs(jiffies - l->prev_retr);
1766
1767 if (less(*to, *from))
1768 return false;
1769
1770 /* New retransmission request */
1771 if ((elapsed > TIPC_BC_RETR_LIMIT) ||
1772 less(*to, l->prev_from) || more(*from, l->prev_to)) {
1773 l->prev_from = *from;
1774 l->prev_to = *to;
1775 l->prev_retr = jiffies;
1776 return true;
1777 }
1778
1779 /* Inside range of previous retransmit */
1780 if (!less(*from, l->prev_from) && !more(*to, l->prev_to))
1781 return false;
1782
1783 /* Fully or partially outside previous range => exclude overlap */
1784 if (less(*from, l->prev_from)) {
1785 *to = l->prev_from - 1;
1786 l->prev_from = *from;
1787 }
1788 if (more(*to, l->prev_to)) {
1789 *from = l->prev_to + 1;
1790 l->prev_to = *to;
1791 }
1792 l->prev_retr = jiffies;
1793 return true;
1794 }
1795
1796 /* tipc_link_bc_sync_rcv - update rcv link according to peer's send state
1797 */
1798 int tipc_link_bc_sync_rcv(struct tipc_link *l, struct tipc_msg *hdr,
1799 struct sk_buff_head *xmitq)
1800 {
1801 struct tipc_link *snd_l = l->bc_sndlink;
1802 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
1803 u16 from = msg_bcast_ack(hdr) + 1;
1804 u16 to = from + msg_bc_gap(hdr) - 1;
1805 int rc = 0;
1806
1807 if (!link_is_up(l))
1808 return rc;
1809
1810 if (!msg_peer_node_is_up(hdr))
1811 return rc;
1812
1813 /* Open when peer ackowledges our bcast init msg (pkt #1) */
1814 if (msg_ack(hdr))
1815 l->bc_peer_is_up = true;
1816
1817 if (!l->bc_peer_is_up)
1818 return rc;
1819
1820 l->stats.recv_nacks++;
1821
1822 /* Ignore if peers_snd_nxt goes beyond receive window */
1823 if (more(peers_snd_nxt, l->rcv_nxt + l->window))
1824 return rc;
1825
1826 if (link_bc_retr_eval(snd_l, &from, &to))
1827 rc = tipc_link_retrans(snd_l, l, from, to, xmitq);
1828
1829 l->snd_nxt = peers_snd_nxt;
1830 if (link_bc_rcv_gap(l))
1831 rc |= TIPC_LINK_SND_STATE;
1832
1833 /* Return now if sender supports nack via STATE messages */
1834 if (l->peer_caps & TIPC_BCAST_STATE_NACK)
1835 return rc;
1836
1837 /* Otherwise, be backwards compatible */
1838
1839 if (!more(peers_snd_nxt, l->rcv_nxt)) {
1840 l->nack_state = BC_NACK_SND_CONDITIONAL;
1841 return 0;
1842 }
1843
1844 /* Don't NACK if one was recently sent or peeked */
1845 if (l->nack_state == BC_NACK_SND_SUPPRESS) {
1846 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
1847 return 0;
1848 }
1849
1850 /* Conditionally delay NACK sending until next synch rcv */
1851 if (l->nack_state == BC_NACK_SND_CONDITIONAL) {
1852 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
1853 if ((peers_snd_nxt - l->rcv_nxt) < TIPC_MIN_LINK_WIN)
1854 return 0;
1855 }
1856
1857 /* Send NACK now but suppress next one */
1858 tipc_link_build_bc_proto_msg(l, true, peers_snd_nxt, xmitq);
1859 l->nack_state = BC_NACK_SND_SUPPRESS;
1860 return 0;
1861 }
1862
1863 void tipc_link_bc_ack_rcv(struct tipc_link *l, u16 acked,
1864 struct sk_buff_head *xmitq)
1865 {
1866 struct sk_buff *skb, *tmp;
1867 struct tipc_link *snd_l = l->bc_sndlink;
1868
1869 if (!link_is_up(l) || !l->bc_peer_is_up)
1870 return;
1871
1872 if (!more(acked, l->acked))
1873 return;
1874
1875 /* Skip over packets peer has already acked */
1876 skb_queue_walk(&snd_l->transmq, skb) {
1877 if (more(buf_seqno(skb), l->acked))
1878 break;
1879 }
1880
1881 /* Update/release the packets peer is acking now */
1882 skb_queue_walk_from_safe(&snd_l->transmq, skb, tmp) {
1883 if (more(buf_seqno(skb), acked))
1884 break;
1885 if (!--TIPC_SKB_CB(skb)->ackers) {
1886 __skb_unlink(skb, &snd_l->transmq);
1887 kfree_skb(skb);
1888 }
1889 }
1890 l->acked = acked;
1891 tipc_link_advance_backlog(snd_l, xmitq);
1892 if (unlikely(!skb_queue_empty(&snd_l->wakeupq)))
1893 link_prepare_wakeup(snd_l);
1894 }
1895
1896 /* tipc_link_bc_nack_rcv(): receive broadcast nack message
1897 * This function is here for backwards compatibility, since
1898 * no BCAST_PROTOCOL/STATE messages occur from TIPC v2.5.
1899 */
1900 int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb,
1901 struct sk_buff_head *xmitq)
1902 {
1903 struct tipc_msg *hdr = buf_msg(skb);
1904 u32 dnode = msg_destnode(hdr);
1905 int mtyp = msg_type(hdr);
1906 u16 acked = msg_bcast_ack(hdr);
1907 u16 from = acked + 1;
1908 u16 to = msg_bcgap_to(hdr);
1909 u16 peers_snd_nxt = to + 1;
1910 int rc = 0;
1911
1912 kfree_skb(skb);
1913
1914 if (!tipc_link_is_up(l) || !l->bc_peer_is_up)
1915 return 0;
1916
1917 if (mtyp != STATE_MSG)
1918 return 0;
1919
1920 if (dnode == tipc_own_addr(l->net)) {
1921 tipc_link_bc_ack_rcv(l, acked, xmitq);
1922 rc = tipc_link_retrans(l->bc_sndlink, l, from, to, xmitq);
1923 l->stats.recv_nacks++;
1924 return rc;
1925 }
1926
1927 /* Msg for other node => suppress own NACK at next sync if applicable */
1928 if (more(peers_snd_nxt, l->rcv_nxt) && !less(l->rcv_nxt, from))
1929 l->nack_state = BC_NACK_SND_SUPPRESS;
1930
1931 return 0;
1932 }
1933
1934 void tipc_link_set_queue_limits(struct tipc_link *l, u32 win)
1935 {
1936 int max_bulk = TIPC_MAX_PUBL / (l->mtu / ITEM_SIZE);
1937
1938 l->window = win;
1939 l->backlog[TIPC_LOW_IMPORTANCE].limit = max_t(u16, 50, win);
1940 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = max_t(u16, 100, win * 2);
1941 l->backlog[TIPC_HIGH_IMPORTANCE].limit = max_t(u16, 150, win * 3);
1942 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = max_t(u16, 200, win * 4);
1943 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk;
1944 }
1945
1946 /**
1947 * link_reset_stats - reset link statistics
1948 * @l: pointer to link
1949 */
1950 void tipc_link_reset_stats(struct tipc_link *l)
1951 {
1952 memset(&l->stats, 0, sizeof(l->stats));
1953 }
1954
1955 static void link_print(struct tipc_link *l, const char *str)
1956 {
1957 struct sk_buff *hskb = skb_peek(&l->transmq);
1958 u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1;
1959 u16 tail = l->snd_nxt - 1;
1960
1961 pr_info("%s Link <%s> state %x\n", str, l->name, l->state);
1962 pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n",
1963 skb_queue_len(&l->transmq), head, tail,
1964 skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt);
1965 }
1966
1967 /* Parse and validate nested (link) properties valid for media, bearer and link
1968 */
1969 int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
1970 {
1971 int err;
1972
1973 err = nla_parse_nested(props, TIPC_NLA_PROP_MAX, prop,
1974 tipc_nl_prop_policy, NULL);
1975 if (err)
1976 return err;
1977
1978 if (props[TIPC_NLA_PROP_PRIO]) {
1979 u32 prio;
1980
1981 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
1982 if (prio > TIPC_MAX_LINK_PRI)
1983 return -EINVAL;
1984 }
1985
1986 if (props[TIPC_NLA_PROP_TOL]) {
1987 u32 tol;
1988
1989 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
1990 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
1991 return -EINVAL;
1992 }
1993
1994 if (props[TIPC_NLA_PROP_WIN]) {
1995 u32 win;
1996
1997 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
1998 if ((win < TIPC_MIN_LINK_WIN) || (win > TIPC_MAX_LINK_WIN))
1999 return -EINVAL;
2000 }
2001
2002 return 0;
2003 }
2004
2005 static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
2006 {
2007 int i;
2008 struct nlattr *stats;
2009
2010 struct nla_map {
2011 u32 key;
2012 u32 val;
2013 };
2014
2015 struct nla_map map[] = {
2016 {TIPC_NLA_STATS_RX_INFO, 0},
2017 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
2018 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
2019 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
2020 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
2021 {TIPC_NLA_STATS_TX_INFO, 0},
2022 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
2023 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
2024 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
2025 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
2026 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
2027 s->msg_length_counts : 1},
2028 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
2029 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
2030 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
2031 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
2032 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
2033 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
2034 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
2035 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
2036 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
2037 {TIPC_NLA_STATS_RX_STATES, s->recv_states},
2038 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
2039 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
2040 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
2041 {TIPC_NLA_STATS_TX_STATES, s->sent_states},
2042 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
2043 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
2044 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
2045 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
2046 {TIPC_NLA_STATS_DUPLICATES, s->duplicates},
2047 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
2048 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
2049 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
2050 (s->accu_queue_sz / s->queue_sz_counts) : 0}
2051 };
2052
2053 stats = nla_nest_start(skb, TIPC_NLA_LINK_STATS);
2054 if (!stats)
2055 return -EMSGSIZE;
2056
2057 for (i = 0; i < ARRAY_SIZE(map); i++)
2058 if (nla_put_u32(skb, map[i].key, map[i].val))
2059 goto msg_full;
2060
2061 nla_nest_end(skb, stats);
2062
2063 return 0;
2064 msg_full:
2065 nla_nest_cancel(skb, stats);
2066
2067 return -EMSGSIZE;
2068 }
2069
2070 /* Caller should hold appropriate locks to protect the link */
2071 int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
2072 struct tipc_link *link, int nlflags)
2073 {
2074 u32 self = tipc_own_addr(net);
2075 struct nlattr *attrs;
2076 struct nlattr *prop;
2077 void *hdr;
2078 int err;
2079
2080 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2081 nlflags, TIPC_NL_LINK_GET);
2082 if (!hdr)
2083 return -EMSGSIZE;
2084
2085 attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK);
2086 if (!attrs)
2087 goto msg_full;
2088
2089 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
2090 goto attr_msg_full;
2091 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST, tipc_cluster_mask(self)))
2092 goto attr_msg_full;
2093 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu))
2094 goto attr_msg_full;
2095 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->stats.recv_pkts))
2096 goto attr_msg_full;
2097 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->stats.sent_pkts))
2098 goto attr_msg_full;
2099
2100 if (tipc_link_is_up(link))
2101 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2102 goto attr_msg_full;
2103 if (link->active)
2104 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
2105 goto attr_msg_full;
2106
2107 prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP);
2108 if (!prop)
2109 goto attr_msg_full;
2110 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2111 goto prop_msg_full;
2112 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
2113 goto prop_msg_full;
2114 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
2115 link->window))
2116 goto prop_msg_full;
2117 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2118 goto prop_msg_full;
2119 nla_nest_end(msg->skb, prop);
2120
2121 err = __tipc_nl_add_stats(msg->skb, &link->stats);
2122 if (err)
2123 goto attr_msg_full;
2124
2125 nla_nest_end(msg->skb, attrs);
2126 genlmsg_end(msg->skb, hdr);
2127
2128 return 0;
2129
2130 prop_msg_full:
2131 nla_nest_cancel(msg->skb, prop);
2132 attr_msg_full:
2133 nla_nest_cancel(msg->skb, attrs);
2134 msg_full:
2135 genlmsg_cancel(msg->skb, hdr);
2136
2137 return -EMSGSIZE;
2138 }
2139
2140 static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb,
2141 struct tipc_stats *stats)
2142 {
2143 int i;
2144 struct nlattr *nest;
2145
2146 struct nla_map {
2147 __u32 key;
2148 __u32 val;
2149 };
2150
2151 struct nla_map map[] = {
2152 {TIPC_NLA_STATS_RX_INFO, stats->recv_pkts},
2153 {TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments},
2154 {TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented},
2155 {TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles},
2156 {TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled},
2157 {TIPC_NLA_STATS_TX_INFO, stats->sent_pkts},
2158 {TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments},
2159 {TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented},
2160 {TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles},
2161 {TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled},
2162 {TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks},
2163 {TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv},
2164 {TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks},
2165 {TIPC_NLA_STATS_TX_ACKS, stats->sent_acks},
2166 {TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted},
2167 {TIPC_NLA_STATS_DUPLICATES, stats->duplicates},
2168 {TIPC_NLA_STATS_LINK_CONGS, stats->link_congs},
2169 {TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz},
2170 {TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ?
2171 (stats->accu_queue_sz / stats->queue_sz_counts) : 0}
2172 };
2173
2174 nest = nla_nest_start(skb, TIPC_NLA_LINK_STATS);
2175 if (!nest)
2176 return -EMSGSIZE;
2177
2178 for (i = 0; i < ARRAY_SIZE(map); i++)
2179 if (nla_put_u32(skb, map[i].key, map[i].val))
2180 goto msg_full;
2181
2182 nla_nest_end(skb, nest);
2183
2184 return 0;
2185 msg_full:
2186 nla_nest_cancel(skb, nest);
2187
2188 return -EMSGSIZE;
2189 }
2190
2191 int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg)
2192 {
2193 int err;
2194 void *hdr;
2195 struct nlattr *attrs;
2196 struct nlattr *prop;
2197 struct tipc_net *tn = net_generic(net, tipc_net_id);
2198 struct tipc_link *bcl = tn->bcl;
2199
2200 if (!bcl)
2201 return 0;
2202
2203 tipc_bcast_lock(net);
2204
2205 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2206 NLM_F_MULTI, TIPC_NL_LINK_GET);
2207 if (!hdr) {
2208 tipc_bcast_unlock(net);
2209 return -EMSGSIZE;
2210 }
2211
2212 attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK);
2213 if (!attrs)
2214 goto msg_full;
2215
2216 /* The broadcast link is always up */
2217 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2218 goto attr_msg_full;
2219
2220 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST))
2221 goto attr_msg_full;
2222 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name))
2223 goto attr_msg_full;
2224 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, 0))
2225 goto attr_msg_full;
2226 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, 0))
2227 goto attr_msg_full;
2228
2229 prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP);
2230 if (!prop)
2231 goto attr_msg_full;
2232 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->window))
2233 goto prop_msg_full;
2234 nla_nest_end(msg->skb, prop);
2235
2236 err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats);
2237 if (err)
2238 goto attr_msg_full;
2239
2240 tipc_bcast_unlock(net);
2241 nla_nest_end(msg->skb, attrs);
2242 genlmsg_end(msg->skb, hdr);
2243
2244 return 0;
2245
2246 prop_msg_full:
2247 nla_nest_cancel(msg->skb, prop);
2248 attr_msg_full:
2249 nla_nest_cancel(msg->skb, attrs);
2250 msg_full:
2251 tipc_bcast_unlock(net);
2252 genlmsg_cancel(msg->skb, hdr);
2253
2254 return -EMSGSIZE;
2255 }
2256
2257 void tipc_link_set_tolerance(struct tipc_link *l, u32 tol,
2258 struct sk_buff_head *xmitq)
2259 {
2260 l->tolerance = tol;
2261 if (l->bc_rcvlink)
2262 l->bc_rcvlink->tolerance = tol;
2263 if (link_is_up(l))
2264 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, tol, 0, xmitq);
2265 }
2266
2267 void tipc_link_set_prio(struct tipc_link *l, u32 prio,
2268 struct sk_buff_head *xmitq)
2269 {
2270 l->priority = prio;
2271 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, prio, xmitq);
2272 }
2273
2274 void tipc_link_set_abort_limit(struct tipc_link *l, u32 limit)
2275 {
2276 l->abort_limit = limit;
2277 }
Linux with added FPC-III support