?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
Merge branch 'for-3.11' of git://linux-nfs.org/~bfields/linux
[linux-2.6.git] / net / tipc / link.c
blob0cc3d9015c5d5bb6a1629251d7a636f41239db6f
1 /*
2 * net/tipc/link.c: TIPC link code
3 *
4 * Copyright (c) 1996-2007, 2012, 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 "link.h"
39 #include "port.h"
40 #include "name_distr.h"
41 #include "discover.h"
42 #include "config.h"
43
44 #include <linux/pkt_sched.h>
45
46 /*
47 * Error message prefixes
48 */
49 static const char *link_co_err = "Link changeover error, ";
50 static const char *link_rst_msg = "Resetting link ";
51 static const char *link_unk_evt = "Unknown link event ";
52
53 /*
54 * Out-of-range value for link session numbers
55 */
56 #define INVALID_SESSION 0x10000
57
58 /*
59 * Link state events:
60 */
61 #define STARTING_EVT 856384768 /* link processing trigger */
62 #define TRAFFIC_MSG_EVT 560815u /* rx'd ??? */
63 #define TIMEOUT_EVT 560817u /* link timer expired */
64
65 /*
66 * The following two 'message types' is really just implementation
67 * data conveniently stored in the message header.
68 * They must not be considered part of the protocol
69 */
70 #define OPEN_MSG 0
71 #define CLOSED_MSG 1
72
73 /*
74 * State value stored in 'exp_msg_count'
75 */
76 #define START_CHANGEOVER 100000u
77
78 /**
79 * struct tipc_link_name - deconstructed link name
80 * @addr_local: network address of node at this end
81 * @if_local: name of interface at this end
82 * @addr_peer: network address of node at far end
83 * @if_peer: name of interface at far end
84 */
85 struct tipc_link_name {
86 u32 addr_local;
87 char if_local[TIPC_MAX_IF_NAME];
88 u32 addr_peer;
89 char if_peer[TIPC_MAX_IF_NAME];
90 };
91
92 static void link_handle_out_of_seq_msg(struct tipc_link *l_ptr,
93 struct sk_buff *buf);
94 static void link_recv_proto_msg(struct tipc_link *l_ptr, struct sk_buff *buf);
95 static int link_recv_changeover_msg(struct tipc_link **l_ptr,
96 struct sk_buff **buf);
97 static void link_set_supervision_props(struct tipc_link *l_ptr, u32 tolerance);
98 static int link_send_sections_long(struct tipc_port *sender,
99 struct iovec const *msg_sect,
100 u32 num_sect, unsigned int total_len,
101 u32 destnode);
102 static void link_state_event(struct tipc_link *l_ptr, u32 event);
103 static void link_reset_statistics(struct tipc_link *l_ptr);
104 static void link_print(struct tipc_link *l_ptr, const char *str);
105 static void link_start(struct tipc_link *l_ptr);
106 static int link_send_long_buf(struct tipc_link *l_ptr, struct sk_buff *buf);
107 static void tipc_link_send_sync(struct tipc_link *l);
108 static void tipc_link_recv_sync(struct tipc_node *n, struct sk_buff *buf);
109
110 /*
111 * Simple link routines
112 */
113 static unsigned int align(unsigned int i)
114 {
115 return (i + 3) & ~3u;
116 }
117
118 static void link_init_max_pkt(struct tipc_link *l_ptr)
119 {
120 u32 max_pkt;
121
122 max_pkt = (l_ptr->b_ptr->mtu & ~3);
123 if (max_pkt > MAX_MSG_SIZE)
124 max_pkt = MAX_MSG_SIZE;
125
126 l_ptr->max_pkt_target = max_pkt;
127 if (l_ptr->max_pkt_target < MAX_PKT_DEFAULT)
128 l_ptr->max_pkt = l_ptr->max_pkt_target;
129 else
130 l_ptr->max_pkt = MAX_PKT_DEFAULT;
131
132 l_ptr->max_pkt_probes = 0;
133 }
134
135 static u32 link_next_sent(struct tipc_link *l_ptr)
136 {
137 if (l_ptr->next_out)
138 return buf_seqno(l_ptr->next_out);
139 return mod(l_ptr->next_out_no);
140 }
141
142 static u32 link_last_sent(struct tipc_link *l_ptr)
143 {
144 return mod(link_next_sent(l_ptr) - 1);
145 }
146
147 /*
148 * Simple non-static link routines (i.e. referenced outside this file)
149 */
150 int tipc_link_is_up(struct tipc_link *l_ptr)
151 {
152 if (!l_ptr)
153 return 0;
154 return link_working_working(l_ptr) || link_working_unknown(l_ptr);
155 }
156
157 int tipc_link_is_active(struct tipc_link *l_ptr)
158 {
159 return (l_ptr->owner->active_links[0] == l_ptr) ||
160 (l_ptr->owner->active_links[1] == l_ptr);
161 }
162
163 /**
164 * link_name_validate - validate & (optionally) deconstruct tipc_link name
165 * @name: ptr to link name string
166 * @name_parts: ptr to area for link name components (or NULL if not needed)
167 *
168 * Returns 1 if link name is valid, otherwise 0.
169 */
170 static int link_name_validate(const char *name,
171 struct tipc_link_name *name_parts)
172 {
173 char name_copy[TIPC_MAX_LINK_NAME];
174 char *addr_local;
175 char *if_local;
176 char *addr_peer;
177 char *if_peer;
178 char dummy;
179 u32 z_local, c_local, n_local;
180 u32 z_peer, c_peer, n_peer;
181 u32 if_local_len;
182 u32 if_peer_len;
183
184 /* copy link name & ensure length is OK */
185 name_copy[TIPC_MAX_LINK_NAME - 1] = 0;
186 /* need above in case non-Posix strncpy() doesn't pad with nulls */
187 strncpy(name_copy, name, TIPC_MAX_LINK_NAME);
188 if (name_copy[TIPC_MAX_LINK_NAME - 1] != 0)
189 return 0;
190
191 /* ensure all component parts of link name are present */
192 addr_local = name_copy;
193 if_local = strchr(addr_local, ':');
194 if (if_local == NULL)
195 return 0;
196 *(if_local++) = 0;
197 addr_peer = strchr(if_local, '-');
198 if (addr_peer == NULL)
199 return 0;
200 *(addr_peer++) = 0;
201 if_local_len = addr_peer - if_local;
202 if_peer = strchr(addr_peer, ':');
203 if (if_peer == NULL)
204 return 0;
205 *(if_peer++) = 0;
206 if_peer_len = strlen(if_peer) + 1;
207
208 /* validate component parts of link name */
209 if ((sscanf(addr_local, "%u.%u.%u%c",
210 &z_local, &c_local, &n_local, &dummy) != 3) ||
211 (sscanf(addr_peer, "%u.%u.%u%c",
212 &z_peer, &c_peer, &n_peer, &dummy) != 3) ||
213 (z_local > 255) || (c_local > 4095) || (n_local > 4095) ||
214 (z_peer > 255) || (c_peer > 4095) || (n_peer > 4095) ||
215 (if_local_len <= 1) || (if_local_len > TIPC_MAX_IF_NAME) ||
216 (if_peer_len <= 1) || (if_peer_len > TIPC_MAX_IF_NAME))
217 return 0;
218
219 /* return link name components, if necessary */
220 if (name_parts) {
221 name_parts->addr_local = tipc_addr(z_local, c_local, n_local);
222 strcpy(name_parts->if_local, if_local);
223 name_parts->addr_peer = tipc_addr(z_peer, c_peer, n_peer);
224 strcpy(name_parts->if_peer, if_peer);
225 }
226 return 1;
227 }
228
229 /**
230 * link_timeout - handle expiration of link timer
231 * @l_ptr: pointer to link
232 *
233 * This routine must not grab "tipc_net_lock" to avoid a potential deadlock conflict
234 * with tipc_link_delete(). (There is no risk that the node will be deleted by
235 * another thread because tipc_link_delete() always cancels the link timer before
236 * tipc_node_delete() is called.)
237 */
238 static void link_timeout(struct tipc_link *l_ptr)
239 {
240 tipc_node_lock(l_ptr->owner);
241
242 /* update counters used in statistical profiling of send traffic */
243 l_ptr->stats.accu_queue_sz += l_ptr->out_queue_size;
244 l_ptr->stats.queue_sz_counts++;
245
246 if (l_ptr->first_out) {
247 struct tipc_msg *msg = buf_msg(l_ptr->first_out);
248 u32 length = msg_size(msg);
249
250 if ((msg_user(msg) == MSG_FRAGMENTER) &&
251 (msg_type(msg) == FIRST_FRAGMENT)) {
252 length = msg_size(msg_get_wrapped(msg));
253 }
254 if (length) {
255 l_ptr->stats.msg_lengths_total += length;
256 l_ptr->stats.msg_length_counts++;
257 if (length <= 64)
258 l_ptr->stats.msg_length_profile[0]++;
259 else if (length <= 256)
260 l_ptr->stats.msg_length_profile[1]++;
261 else if (length <= 1024)
262 l_ptr->stats.msg_length_profile[2]++;
263 else if (length <= 4096)
264 l_ptr->stats.msg_length_profile[3]++;
265 else if (length <= 16384)
266 l_ptr->stats.msg_length_profile[4]++;
267 else if (length <= 32768)
268 l_ptr->stats.msg_length_profile[5]++;
269 else
270 l_ptr->stats.msg_length_profile[6]++;
271 }
272 }
273
274 /* do all other link processing performed on a periodic basis */
275
276 link_state_event(l_ptr, TIMEOUT_EVT);
277
278 if (l_ptr->next_out)
279 tipc_link_push_queue(l_ptr);
280
281 tipc_node_unlock(l_ptr->owner);
282 }
283
284 static void link_set_timer(struct tipc_link *l_ptr, u32 time)
285 {
286 k_start_timer(&l_ptr->timer, time);
287 }
288
289 /**
290 * tipc_link_create - create a new link
291 * @n_ptr: pointer to associated node
292 * @b_ptr: pointer to associated bearer
293 * @media_addr: media address to use when sending messages over link
294 *
295 * Returns pointer to link.
296 */
297 struct tipc_link *tipc_link_create(struct tipc_node *n_ptr,
298 struct tipc_bearer *b_ptr,
299 const struct tipc_media_addr *media_addr)
300 {
301 struct tipc_link *l_ptr;
302 struct tipc_msg *msg;
303 char *if_name;
304 char addr_string[16];
305 u32 peer = n_ptr->addr;
306
307 if (n_ptr->link_cnt >= 2) {
308 tipc_addr_string_fill(addr_string, n_ptr->addr);
309 pr_err("Attempt to establish third link to %s\n", addr_string);
310 return NULL;
311 }
312
313 if (n_ptr->links[b_ptr->identity]) {
314 tipc_addr_string_fill(addr_string, n_ptr->addr);
315 pr_err("Attempt to establish second link on <%s> to %s\n",
316 b_ptr->name, addr_string);
317 return NULL;
318 }
319
320 l_ptr = kzalloc(sizeof(*l_ptr), GFP_ATOMIC);
321 if (!l_ptr) {
322 pr_warn("Link creation failed, no memory\n");
323 return NULL;
324 }
325
326 l_ptr->addr = peer;
327 if_name = strchr(b_ptr->name, ':') + 1;
328 sprintf(l_ptr->name, "%u.%u.%u:%s-%u.%u.%u:unknown",
329 tipc_zone(tipc_own_addr), tipc_cluster(tipc_own_addr),
330 tipc_node(tipc_own_addr),
331 if_name,
332 tipc_zone(peer), tipc_cluster(peer), tipc_node(peer));
333 /* note: peer i/f name is updated by reset/activate message */
334 memcpy(&l_ptr->media_addr, media_addr, sizeof(*media_addr));
335 l_ptr->owner = n_ptr;
336 l_ptr->checkpoint = 1;
337 l_ptr->peer_session = INVALID_SESSION;
338 l_ptr->b_ptr = b_ptr;
339 link_set_supervision_props(l_ptr, b_ptr->tolerance);
340 l_ptr->state = RESET_UNKNOWN;
341
342 l_ptr->pmsg = (struct tipc_msg *)&l_ptr->proto_msg;
343 msg = l_ptr->pmsg;
344 tipc_msg_init(msg, LINK_PROTOCOL, RESET_MSG, INT_H_SIZE, l_ptr->addr);
345 msg_set_size(msg, sizeof(l_ptr->proto_msg));
346 msg_set_session(msg, (tipc_random & 0xffff));
347 msg_set_bearer_id(msg, b_ptr->identity);
348 strcpy((char *)msg_data(msg), if_name);
349
350 l_ptr->priority = b_ptr->priority;
351 tipc_link_set_queue_limits(l_ptr, b_ptr->window);
352
353 link_init_max_pkt(l_ptr);
354
355 l_ptr->next_out_no = 1;
356 INIT_LIST_HEAD(&l_ptr->waiting_ports);
357
358 link_reset_statistics(l_ptr);
359
360 tipc_node_attach_link(n_ptr, l_ptr);
361
362 k_init_timer(&l_ptr->timer, (Handler)link_timeout, (unsigned long)l_ptr);
363 list_add_tail(&l_ptr->link_list, &b_ptr->links);
364 tipc_k_signal((Handler)link_start, (unsigned long)l_ptr);
365
366 return l_ptr;
367 }
368
369 /**
370 * tipc_link_delete - delete a link
371 * @l_ptr: pointer to link
372 *
373 * Note: 'tipc_net_lock' is write_locked, bearer is locked.
374 * This routine must not grab the node lock until after link timer cancellation
375 * to avoid a potential deadlock situation.
376 */
377 void tipc_link_delete(struct tipc_link *l_ptr)
378 {
379 if (!l_ptr) {
380 pr_err("Attempt to delete non-existent link\n");
381 return;
382 }
383
384 k_cancel_timer(&l_ptr->timer);
385
386 tipc_node_lock(l_ptr->owner);
387 tipc_link_reset(l_ptr);
388 tipc_node_detach_link(l_ptr->owner, l_ptr);
389 tipc_link_stop(l_ptr);
390 list_del_init(&l_ptr->link_list);
391 tipc_node_unlock(l_ptr->owner);
392 k_term_timer(&l_ptr->timer);
393 kfree(l_ptr);
394 }
395
396 static void link_start(struct tipc_link *l_ptr)
397 {
398 tipc_node_lock(l_ptr->owner);
399 link_state_event(l_ptr, STARTING_EVT);
400 tipc_node_unlock(l_ptr->owner);
401 }
402
403 /**
404 * link_schedule_port - schedule port for deferred sending
405 * @l_ptr: pointer to link
406 * @origport: reference to sending port
407 * @sz: amount of data to be sent
408 *
409 * Schedules port for renewed sending of messages after link congestion
410 * has abated.
411 */
412 static int link_schedule_port(struct tipc_link *l_ptr, u32 origport, u32 sz)
413 {
414 struct tipc_port *p_ptr;
415
416 spin_lock_bh(&tipc_port_list_lock);
417 p_ptr = tipc_port_lock(origport);
418 if (p_ptr) {
419 if (!p_ptr->wakeup)
420 goto exit;
421 if (!list_empty(&p_ptr->wait_list))
422 goto exit;
423 p_ptr->congested = 1;
424 p_ptr->waiting_pkts = 1 + ((sz - 1) / l_ptr->max_pkt);
425 list_add_tail(&p_ptr->wait_list, &l_ptr->waiting_ports);
426 l_ptr->stats.link_congs++;
427 exit:
428 tipc_port_unlock(p_ptr);
429 }
430 spin_unlock_bh(&tipc_port_list_lock);
431 return -ELINKCONG;
432 }
433
434 void tipc_link_wakeup_ports(struct tipc_link *l_ptr, int all)
435 {
436 struct tipc_port *p_ptr;
437 struct tipc_port *temp_p_ptr;
438 int win = l_ptr->queue_limit[0] - l_ptr->out_queue_size;
439
440 if (all)
441 win = 100000;
442 if (win <= 0)
443 return;
444 if (!spin_trylock_bh(&tipc_port_list_lock))
445 return;
446 if (link_congested(l_ptr))
447 goto exit;
448 list_for_each_entry_safe(p_ptr, temp_p_ptr, &l_ptr->waiting_ports,
449 wait_list) {
450 if (win <= 0)
451 break;
452 list_del_init(&p_ptr->wait_list);
453 spin_lock_bh(p_ptr->lock);
454 p_ptr->congested = 0;
455 p_ptr->wakeup(p_ptr);
456 win -= p_ptr->waiting_pkts;
457 spin_unlock_bh(p_ptr->lock);
458 }
459
460 exit:
461 spin_unlock_bh(&tipc_port_list_lock);
462 }
463
464 /**
465 * link_release_outqueue - purge link's outbound message queue
466 * @l_ptr: pointer to link
467 */
468 static void link_release_outqueue(struct tipc_link *l_ptr)
469 {
470 struct sk_buff *buf = l_ptr->first_out;
471 struct sk_buff *next;
472
473 while (buf) {
474 next = buf->next;
475 kfree_skb(buf);
476 buf = next;
477 }
478 l_ptr->first_out = NULL;
479 l_ptr->out_queue_size = 0;
480 }
481
482 /**
483 * tipc_link_reset_fragments - purge link's inbound message fragments queue
484 * @l_ptr: pointer to link
485 */
486 void tipc_link_reset_fragments(struct tipc_link *l_ptr)
487 {
488 struct sk_buff *buf = l_ptr->defragm_buf;
489 struct sk_buff *next;
490
491 while (buf) {
492 next = buf->next;
493 kfree_skb(buf);
494 buf = next;
495 }
496 l_ptr->defragm_buf = NULL;
497 }
498
499 /**
500 * tipc_link_stop - purge all inbound and outbound messages associated with link
501 * @l_ptr: pointer to link
502 */
503 void tipc_link_stop(struct tipc_link *l_ptr)
504 {
505 struct sk_buff *buf;
506 struct sk_buff *next;
507
508 buf = l_ptr->oldest_deferred_in;
509 while (buf) {
510 next = buf->next;
511 kfree_skb(buf);
512 buf = next;
513 }
514
515 buf = l_ptr->first_out;
516 while (buf) {
517 next = buf->next;
518 kfree_skb(buf);
519 buf = next;
520 }
521
522 tipc_link_reset_fragments(l_ptr);
523
524 kfree_skb(l_ptr->proto_msg_queue);
525 l_ptr->proto_msg_queue = NULL;
526 }
527
528 void tipc_link_reset(struct tipc_link *l_ptr)
529 {
530 struct sk_buff *buf;
531 u32 prev_state = l_ptr->state;
532 u32 checkpoint = l_ptr->next_in_no;
533 int was_active_link = tipc_link_is_active(l_ptr);
534
535 msg_set_session(l_ptr->pmsg, ((msg_session(l_ptr->pmsg) + 1) & 0xffff));
536
537 /* Link is down, accept any session */
538 l_ptr->peer_session = INVALID_SESSION;
539
540 /* Prepare for max packet size negotiation */
541 link_init_max_pkt(l_ptr);
542
543 l_ptr->state = RESET_UNKNOWN;
544
545 if ((prev_state == RESET_UNKNOWN) || (prev_state == RESET_RESET))
546 return;
547
548 tipc_node_link_down(l_ptr->owner, l_ptr);
549 tipc_bearer_remove_dest(l_ptr->b_ptr, l_ptr->addr);
550
551 if (was_active_link && tipc_node_active_links(l_ptr->owner) &&
552 l_ptr->owner->permit_changeover) {
553 l_ptr->reset_checkpoint = checkpoint;
554 l_ptr->exp_msg_count = START_CHANGEOVER;
555 }
556
557 /* Clean up all queues: */
558 link_release_outqueue(l_ptr);
559 kfree_skb(l_ptr->proto_msg_queue);
560 l_ptr->proto_msg_queue = NULL;
561 buf = l_ptr->oldest_deferred_in;
562 while (buf) {
563 struct sk_buff *next = buf->next;
564 kfree_skb(buf);
565 buf = next;
566 }
567 if (!list_empty(&l_ptr->waiting_ports))
568 tipc_link_wakeup_ports(l_ptr, 1);
569
570 l_ptr->retransm_queue_head = 0;
571 l_ptr->retransm_queue_size = 0;
572 l_ptr->last_out = NULL;
573 l_ptr->first_out = NULL;
574 l_ptr->next_out = NULL;
575 l_ptr->unacked_window = 0;
576 l_ptr->checkpoint = 1;
577 l_ptr->next_out_no = 1;
578 l_ptr->deferred_inqueue_sz = 0;
579 l_ptr->oldest_deferred_in = NULL;
580 l_ptr->newest_deferred_in = NULL;
581 l_ptr->fsm_msg_cnt = 0;
582 l_ptr->stale_count = 0;
583 link_reset_statistics(l_ptr);
584 }
585
586
587 static void link_activate(struct tipc_link *l_ptr)
588 {
589 l_ptr->next_in_no = l_ptr->stats.recv_info = 1;
590 tipc_node_link_up(l_ptr->owner, l_ptr);
591 tipc_bearer_add_dest(l_ptr->b_ptr, l_ptr->addr);
592 }
593
594 /**
595 * link_state_event - link finite state machine
596 * @l_ptr: pointer to link
597 * @event: state machine event to process
598 */
599 static void link_state_event(struct tipc_link *l_ptr, unsigned int event)
600 {
601 struct tipc_link *other;
602 u32 cont_intv = l_ptr->continuity_interval;
603
604 if (!l_ptr->started && (event != STARTING_EVT))
605 return; /* Not yet. */
606
607 if (link_blocked(l_ptr)) {
608 if (event == TIMEOUT_EVT)
609 link_set_timer(l_ptr, cont_intv);
610 return; /* Changeover going on */
611 }
612
613 switch (l_ptr->state) {
614 case WORKING_WORKING:
615 switch (event) {
616 case TRAFFIC_MSG_EVT:
617 case ACTIVATE_MSG:
618 break;
619 case TIMEOUT_EVT:
620 if (l_ptr->next_in_no != l_ptr->checkpoint) {
621 l_ptr->checkpoint = l_ptr->next_in_no;
622 if (tipc_bclink_acks_missing(l_ptr->owner)) {
623 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
624 0, 0, 0, 0, 0);
625 l_ptr->fsm_msg_cnt++;
626 } else if (l_ptr->max_pkt < l_ptr->max_pkt_target) {
627 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
628 1, 0, 0, 0, 0);
629 l_ptr->fsm_msg_cnt++;
630 }
631 link_set_timer(l_ptr, cont_intv);
632 break;
633 }
634 l_ptr->state = WORKING_UNKNOWN;
635 l_ptr->fsm_msg_cnt = 0;
636 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
637 l_ptr->fsm_msg_cnt++;
638 link_set_timer(l_ptr, cont_intv / 4);
639 break;
640 case RESET_MSG:
641 pr_info("%s<%s>, requested by peer\n", link_rst_msg,
642 l_ptr->name);
643 tipc_link_reset(l_ptr);
644 l_ptr->state = RESET_RESET;
645 l_ptr->fsm_msg_cnt = 0;
646 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0);
647 l_ptr->fsm_msg_cnt++;
648 link_set_timer(l_ptr, cont_intv);
649 break;
650 default:
651 pr_err("%s%u in WW state\n", link_unk_evt, event);
652 }
653 break;
654 case WORKING_UNKNOWN:
655 switch (event) {
656 case TRAFFIC_MSG_EVT:
657 case ACTIVATE_MSG:
658 l_ptr->state = WORKING_WORKING;
659 l_ptr->fsm_msg_cnt = 0;
660 link_set_timer(l_ptr, cont_intv);
661 break;
662 case RESET_MSG:
663 pr_info("%s<%s>, requested by peer while probing\n",
664 link_rst_msg, l_ptr->name);
665 tipc_link_reset(l_ptr);
666 l_ptr->state = RESET_RESET;
667 l_ptr->fsm_msg_cnt = 0;
668 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0);
669 l_ptr->fsm_msg_cnt++;
670 link_set_timer(l_ptr, cont_intv);
671 break;
672 case TIMEOUT_EVT:
673 if (l_ptr->next_in_no != l_ptr->checkpoint) {
674 l_ptr->state = WORKING_WORKING;
675 l_ptr->fsm_msg_cnt = 0;
676 l_ptr->checkpoint = l_ptr->next_in_no;
677 if (tipc_bclink_acks_missing(l_ptr->owner)) {
678 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
679 0, 0, 0, 0, 0);
680 l_ptr->fsm_msg_cnt++;
681 }
682 link_set_timer(l_ptr, cont_intv);
683 } else if (l_ptr->fsm_msg_cnt < l_ptr->abort_limit) {
684 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
685 1, 0, 0, 0, 0);
686 l_ptr->fsm_msg_cnt++;
687 link_set_timer(l_ptr, cont_intv / 4);
688 } else { /* Link has failed */
689 pr_warn("%s<%s>, peer not responding\n",
690 link_rst_msg, l_ptr->name);
691 tipc_link_reset(l_ptr);
692 l_ptr->state = RESET_UNKNOWN;
693 l_ptr->fsm_msg_cnt = 0;
694 tipc_link_send_proto_msg(l_ptr, RESET_MSG,
695 0, 0, 0, 0, 0);
696 l_ptr->fsm_msg_cnt++;
697 link_set_timer(l_ptr, cont_intv);
698 }
699 break;
700 default:
701 pr_err("%s%u in WU state\n", link_unk_evt, event);
702 }
703 break;
704 case RESET_UNKNOWN:
705 switch (event) {
706 case TRAFFIC_MSG_EVT:
707 break;
708 case ACTIVATE_MSG:
709 other = l_ptr->owner->active_links[0];
710 if (other && link_working_unknown(other))
711 break;
712 l_ptr->state = WORKING_WORKING;
713 l_ptr->fsm_msg_cnt = 0;
714 link_activate(l_ptr);
715 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
716 l_ptr->fsm_msg_cnt++;
717 if (l_ptr->owner->working_links == 1)
718 tipc_link_send_sync(l_ptr);
719 link_set_timer(l_ptr, cont_intv);
720 break;
721 case RESET_MSG:
722 l_ptr->state = RESET_RESET;
723 l_ptr->fsm_msg_cnt = 0;
724 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 1, 0, 0, 0, 0);
725 l_ptr->fsm_msg_cnt++;
726 link_set_timer(l_ptr, cont_intv);
727 break;
728 case STARTING_EVT:
729 l_ptr->started = 1;
730 /* fall through */
731 case TIMEOUT_EVT:
732 tipc_link_send_proto_msg(l_ptr, RESET_MSG, 0, 0, 0, 0, 0);
733 l_ptr->fsm_msg_cnt++;
734 link_set_timer(l_ptr, cont_intv);
735 break;
736 default:
737 pr_err("%s%u in RU state\n", link_unk_evt, event);
738 }
739 break;
740 case RESET_RESET:
741 switch (event) {
742 case TRAFFIC_MSG_EVT:
743 case ACTIVATE_MSG:
744 other = l_ptr->owner->active_links[0];
745 if (other && link_working_unknown(other))
746 break;
747 l_ptr->state = WORKING_WORKING;
748 l_ptr->fsm_msg_cnt = 0;
749 link_activate(l_ptr);
750 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 1, 0, 0, 0, 0);
751 l_ptr->fsm_msg_cnt++;
752 if (l_ptr->owner->working_links == 1)
753 tipc_link_send_sync(l_ptr);
754 link_set_timer(l_ptr, cont_intv);
755 break;
756 case RESET_MSG:
757 break;
758 case TIMEOUT_EVT:
759 tipc_link_send_proto_msg(l_ptr, ACTIVATE_MSG, 0, 0, 0, 0, 0);
760 l_ptr->fsm_msg_cnt++;
761 link_set_timer(l_ptr, cont_intv);
762 break;
763 default:
764 pr_err("%s%u in RR state\n", link_unk_evt, event);
765 }
766 break;
767 default:
768 pr_err("Unknown link state %u/%u\n", l_ptr->state, event);
769 }
770 }
771
772 /*
773 * link_bundle_buf(): Append contents of a buffer to
774 * the tail of an existing one.
775 */
776 static int link_bundle_buf(struct tipc_link *l_ptr, struct sk_buff *bundler,
777 struct sk_buff *buf)
778 {
779 struct tipc_msg *bundler_msg = buf_msg(bundler);
780 struct tipc_msg *msg = buf_msg(buf);
781 u32 size = msg_size(msg);
782 u32 bundle_size = msg_size(bundler_msg);
783 u32 to_pos = align(bundle_size);
784 u32 pad = to_pos - bundle_size;
785
786 if (msg_user(bundler_msg) != MSG_BUNDLER)
787 return 0;
788 if (msg_type(bundler_msg) != OPEN_MSG)
789 return 0;
790 if (skb_tailroom(bundler) < (pad + size))
791 return 0;
792 if (l_ptr->max_pkt < (to_pos + size))
793 return 0;
794
795 skb_put(bundler, pad + size);
796 skb_copy_to_linear_data_offset(bundler, to_pos, buf->data, size);
797 msg_set_size(bundler_msg, to_pos + size);
798 msg_set_msgcnt(bundler_msg, msg_msgcnt(bundler_msg) + 1);
799 kfree_skb(buf);
800 l_ptr->stats.sent_bundled++;
801 return 1;
802 }
803
804 static void link_add_to_outqueue(struct tipc_link *l_ptr,
805 struct sk_buff *buf,
806 struct tipc_msg *msg)
807 {
808 u32 ack = mod(l_ptr->next_in_no - 1);
809 u32 seqno = mod(l_ptr->next_out_no++);
810
811 msg_set_word(msg, 2, ((ack << 16) | seqno));
812 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
813 buf->next = NULL;
814 if (l_ptr->first_out) {
815 l_ptr->last_out->next = buf;
816 l_ptr->last_out = buf;
817 } else
818 l_ptr->first_out = l_ptr->last_out = buf;
819
820 l_ptr->out_queue_size++;
821 if (l_ptr->out_queue_size > l_ptr->stats.max_queue_sz)
822 l_ptr->stats.max_queue_sz = l_ptr->out_queue_size;
823 }
824
825 static void link_add_chain_to_outqueue(struct tipc_link *l_ptr,
826 struct sk_buff *buf_chain,
827 u32 long_msgno)
828 {
829 struct sk_buff *buf;
830 struct tipc_msg *msg;
831
832 if (!l_ptr->next_out)
833 l_ptr->next_out = buf_chain;
834 while (buf_chain) {
835 buf = buf_chain;
836 buf_chain = buf_chain->next;
837
838 msg = buf_msg(buf);
839 msg_set_long_msgno(msg, long_msgno);
840 link_add_to_outqueue(l_ptr, buf, msg);
841 }
842 }
843
844 /*
845 * tipc_link_send_buf() is the 'full path' for messages, called from
846 * inside TIPC when the 'fast path' in tipc_send_buf
847 * has failed, and from link_send()
848 */
849 int tipc_link_send_buf(struct tipc_link *l_ptr, struct sk_buff *buf)
850 {
851 struct tipc_msg *msg = buf_msg(buf);
852 u32 size = msg_size(msg);
853 u32 dsz = msg_data_sz(msg);
854 u32 queue_size = l_ptr->out_queue_size;
855 u32 imp = tipc_msg_tot_importance(msg);
856 u32 queue_limit = l_ptr->queue_limit[imp];
857 u32 max_packet = l_ptr->max_pkt;
858
859 /* Match msg importance against queue limits: */
860 if (unlikely(queue_size >= queue_limit)) {
861 if (imp <= TIPC_CRITICAL_IMPORTANCE) {
862 link_schedule_port(l_ptr, msg_origport(msg), size);
863 kfree_skb(buf);
864 return -ELINKCONG;
865 }
866 kfree_skb(buf);
867 if (imp > CONN_MANAGER) {
868 pr_warn("%s<%s>, send queue full", link_rst_msg,
869 l_ptr->name);
870 tipc_link_reset(l_ptr);
871 }
872 return dsz;
873 }
874
875 /* Fragmentation needed ? */
876 if (size > max_packet)
877 return link_send_long_buf(l_ptr, buf);
878
879 /* Packet can be queued or sent. */
880 if (likely(!tipc_bearer_blocked(l_ptr->b_ptr) &&
881 !link_congested(l_ptr))) {
882 link_add_to_outqueue(l_ptr, buf, msg);
883
884 tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr);
885 l_ptr->unacked_window = 0;
886 return dsz;
887 }
888 /* Congestion: can message be bundled ? */
889 if ((msg_user(msg) != CHANGEOVER_PROTOCOL) &&
890 (msg_user(msg) != MSG_FRAGMENTER)) {
891
892 /* Try adding message to an existing bundle */
893 if (l_ptr->next_out &&
894 link_bundle_buf(l_ptr, l_ptr->last_out, buf))
895 return dsz;
896
897 /* Try creating a new bundle */
898 if (size <= max_packet * 2 / 3) {
899 struct sk_buff *bundler = tipc_buf_acquire(max_packet);
900 struct tipc_msg bundler_hdr;
901
902 if (bundler) {
903 tipc_msg_init(&bundler_hdr, MSG_BUNDLER, OPEN_MSG,
904 INT_H_SIZE, l_ptr->addr);
905 skb_copy_to_linear_data(bundler, &bundler_hdr,
906 INT_H_SIZE);
907 skb_trim(bundler, INT_H_SIZE);
908 link_bundle_buf(l_ptr, bundler, buf);
909 buf = bundler;
910 msg = buf_msg(buf);
911 l_ptr->stats.sent_bundles++;
912 }
913 }
914 }
915 if (!l_ptr->next_out)
916 l_ptr->next_out = buf;
917 link_add_to_outqueue(l_ptr, buf, msg);
918 return dsz;
919 }
920
921 /*
922 * tipc_link_send(): same as tipc_link_send_buf(), but the link to use has
923 * not been selected yet, and the the owner node is not locked
924 * Called by TIPC internal users, e.g. the name distributor
925 */
926 int tipc_link_send(struct sk_buff *buf, u32 dest, u32 selector)
927 {
928 struct tipc_link *l_ptr;
929 struct tipc_node *n_ptr;
930 int res = -ELINKCONG;
931
932 read_lock_bh(&tipc_net_lock);
933 n_ptr = tipc_node_find(dest);
934 if (n_ptr) {
935 tipc_node_lock(n_ptr);
936 l_ptr = n_ptr->active_links[selector & 1];
937 if (l_ptr)
938 res = tipc_link_send_buf(l_ptr, buf);
939 else
940 kfree_skb(buf);
941 tipc_node_unlock(n_ptr);
942 } else {
943 kfree_skb(buf);
944 }
945 read_unlock_bh(&tipc_net_lock);
946 return res;
947 }
948
949 /*
950 * tipc_link_send_sync - synchronize broadcast link endpoints.
951 *
952 * Give a newly added peer node the sequence number where it should
953 * start receiving and acking broadcast packets.
954 *
955 * Called with node locked
956 */
957 static void tipc_link_send_sync(struct tipc_link *l)
958 {
959 struct sk_buff *buf;
960 struct tipc_msg *msg;
961
962 buf = tipc_buf_acquire(INT_H_SIZE);
963 if (!buf)
964 return;
965
966 msg = buf_msg(buf);
967 tipc_msg_init(msg, BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE, l->addr);
968 msg_set_last_bcast(msg, l->owner->bclink.acked);
969 link_add_chain_to_outqueue(l, buf, 0);
970 tipc_link_push_queue(l);
971 }
972
973 /*
974 * tipc_link_recv_sync - synchronize broadcast link endpoints.
975 * Receive the sequence number where we should start receiving and
976 * acking broadcast packets from a newly added peer node, and open
977 * up for reception of such packets.
978 *
979 * Called with node locked
980 */
981 static void tipc_link_recv_sync(struct tipc_node *n, struct sk_buff *buf)
982 {
983 struct tipc_msg *msg = buf_msg(buf);
984
985 n->bclink.last_sent = n->bclink.last_in = msg_last_bcast(msg);
986 n->bclink.recv_permitted = true;
987 kfree_skb(buf);
988 }
989
990 /*
991 * tipc_link_send_names - send name table entries to new neighbor
992 *
993 * Send routine for bulk delivery of name table messages when contact
994 * with a new neighbor occurs. No link congestion checking is performed
995 * because name table messages *must* be delivered. The messages must be
996 * small enough not to require fragmentation.
997 * Called without any locks held.
998 */
999 void tipc_link_send_names(struct list_head *message_list, u32 dest)
1000 {
1001 struct tipc_node *n_ptr;
1002 struct tipc_link *l_ptr;
1003 struct sk_buff *buf;
1004 struct sk_buff *temp_buf;
1005
1006 if (list_empty(message_list))
1007 return;
1008
1009 read_lock_bh(&tipc_net_lock);
1010 n_ptr = tipc_node_find(dest);
1011 if (n_ptr) {
1012 tipc_node_lock(n_ptr);
1013 l_ptr = n_ptr->active_links[0];
1014 if (l_ptr) {
1015 /* convert circular list to linear list */
1016 ((struct sk_buff *)message_list->prev)->next = NULL;
1017 link_add_chain_to_outqueue(l_ptr,
1018 (struct sk_buff *)message_list->next, 0);
1019 tipc_link_push_queue(l_ptr);
1020 INIT_LIST_HEAD(message_list);
1021 }
1022 tipc_node_unlock(n_ptr);
1023 }
1024 read_unlock_bh(&tipc_net_lock);
1025
1026 /* discard the messages if they couldn't be sent */
1027 list_for_each_safe(buf, temp_buf, ((struct sk_buff *)message_list)) {
1028 list_del((struct list_head *)buf);
1029 kfree_skb(buf);
1030 }
1031 }
1032
1033 /*
1034 * link_send_buf_fast: Entry for data messages where the
1035 * destination link is known and the header is complete,
1036 * inclusive total message length. Very time critical.
1037 * Link is locked. Returns user data length.
1038 */
1039 static int link_send_buf_fast(struct tipc_link *l_ptr, struct sk_buff *buf,
1040 u32 *used_max_pkt)
1041 {
1042 struct tipc_msg *msg = buf_msg(buf);
1043 int res = msg_data_sz(msg);
1044
1045 if (likely(!link_congested(l_ptr))) {
1046 if (likely(msg_size(msg) <= l_ptr->max_pkt)) {
1047 if (likely(!tipc_bearer_blocked(l_ptr->b_ptr))) {
1048 link_add_to_outqueue(l_ptr, buf, msg);
1049 tipc_bearer_send(l_ptr->b_ptr, buf,
1050 &l_ptr->media_addr);
1051 l_ptr->unacked_window = 0;
1052 return res;
1053 }
1054 } else
1055 *used_max_pkt = l_ptr->max_pkt;
1056 }
1057 return tipc_link_send_buf(l_ptr, buf); /* All other cases */
1058 }
1059
1060 /*
1061 * tipc_link_send_sections_fast: Entry for messages where the
1062 * destination processor is known and the header is complete,
1063 * except for total message length.
1064 * Returns user data length or errno.
1065 */
1066 int tipc_link_send_sections_fast(struct tipc_port *sender,
1067 struct iovec const *msg_sect,
1068 const u32 num_sect, unsigned int total_len,
1069 u32 destaddr)
1070 {
1071 struct tipc_msg *hdr = &sender->phdr;
1072 struct tipc_link *l_ptr;
1073 struct sk_buff *buf;
1074 struct tipc_node *node;
1075 int res;
1076 u32 selector = msg_origport(hdr) & 1;
1077
1078 again:
1079 /*
1080 * Try building message using port's max_pkt hint.
1081 * (Must not hold any locks while building message.)
1082 */
1083 res = tipc_msg_build(hdr, msg_sect, num_sect, total_len,
1084 sender->max_pkt, &buf);
1085 /* Exit if build request was invalid */
1086 if (unlikely(res < 0))
1087 return res;
1088
1089 read_lock_bh(&tipc_net_lock);
1090 node = tipc_node_find(destaddr);
1091 if (likely(node)) {
1092 tipc_node_lock(node);
1093 l_ptr = node->active_links[selector];
1094 if (likely(l_ptr)) {
1095 if (likely(buf)) {
1096 res = link_send_buf_fast(l_ptr, buf,
1097 &sender->max_pkt);
1098 exit:
1099 tipc_node_unlock(node);
1100 read_unlock_bh(&tipc_net_lock);
1101 return res;
1102 }
1103
1104 /* Exit if link (or bearer) is congested */
1105 if (link_congested(l_ptr) ||
1106 tipc_bearer_blocked(l_ptr->b_ptr)) {
1107 res = link_schedule_port(l_ptr,
1108 sender->ref, res);
1109 goto exit;
1110 }
1111
1112 /*
1113 * Message size exceeds max_pkt hint; update hint,
1114 * then re-try fast path or fragment the message
1115 */
1116 sender->max_pkt = l_ptr->max_pkt;
1117 tipc_node_unlock(node);
1118 read_unlock_bh(&tipc_net_lock);
1119
1120
1121 if ((msg_hdr_sz(hdr) + res) <= sender->max_pkt)
1122 goto again;
1123
1124 return link_send_sections_long(sender, msg_sect,
1125 num_sect, total_len,
1126 destaddr);
1127 }
1128 tipc_node_unlock(node);
1129 }
1130 read_unlock_bh(&tipc_net_lock);
1131
1132 /* Couldn't find a link to the destination node */
1133 if (buf)
1134 return tipc_reject_msg(buf, TIPC_ERR_NO_NODE);
1135 if (res >= 0)
1136 return tipc_port_reject_sections(sender, hdr, msg_sect, num_sect,
1137 total_len, TIPC_ERR_NO_NODE);
1138 return res;
1139 }
1140
1141 /*
1142 * link_send_sections_long(): Entry for long messages where the
1143 * destination node is known and the header is complete,
1144 * inclusive total message length.
1145 * Link and bearer congestion status have been checked to be ok,
1146 * and are ignored if they change.
1147 *
1148 * Note that fragments do not use the full link MTU so that they won't have
1149 * to undergo refragmentation if link changeover causes them to be sent
1150 * over another link with an additional tunnel header added as prefix.
1151 * (Refragmentation will still occur if the other link has a smaller MTU.)
1152 *
1153 * Returns user data length or errno.
1154 */
1155 static int link_send_sections_long(struct tipc_port *sender,
1156 struct iovec const *msg_sect,
1157 u32 num_sect, unsigned int total_len,
1158 u32 destaddr)
1159 {
1160 struct tipc_link *l_ptr;
1161 struct tipc_node *node;
1162 struct tipc_msg *hdr = &sender->phdr;
1163 u32 dsz = total_len;
1164 u32 max_pkt, fragm_sz, rest;
1165 struct tipc_msg fragm_hdr;
1166 struct sk_buff *buf, *buf_chain, *prev;
1167 u32 fragm_crs, fragm_rest, hsz, sect_rest;
1168 const unchar *sect_crs;
1169 int curr_sect;
1170 u32 fragm_no;
1171 int res = 0;
1172
1173 again:
1174 fragm_no = 1;
1175 max_pkt = sender->max_pkt - INT_H_SIZE;
1176 /* leave room for tunnel header in case of link changeover */
1177 fragm_sz = max_pkt - INT_H_SIZE;
1178 /* leave room for fragmentation header in each fragment */
1179 rest = dsz;
1180 fragm_crs = 0;
1181 fragm_rest = 0;
1182 sect_rest = 0;
1183 sect_crs = NULL;
1184 curr_sect = -1;
1185
1186 /* Prepare reusable fragment header */
1187 tipc_msg_init(&fragm_hdr, MSG_FRAGMENTER, FIRST_FRAGMENT,
1188 INT_H_SIZE, msg_destnode(hdr));
1189 msg_set_size(&fragm_hdr, max_pkt);
1190 msg_set_fragm_no(&fragm_hdr, 1);
1191
1192 /* Prepare header of first fragment */
1193 buf_chain = buf = tipc_buf_acquire(max_pkt);
1194 if (!buf)
1195 return -ENOMEM;
1196 buf->next = NULL;
1197 skb_copy_to_linear_data(buf, &fragm_hdr, INT_H_SIZE);
1198 hsz = msg_hdr_sz(hdr);
1199 skb_copy_to_linear_data_offset(buf, INT_H_SIZE, hdr, hsz);
1200
1201 /* Chop up message */
1202 fragm_crs = INT_H_SIZE + hsz;
1203 fragm_rest = fragm_sz - hsz;
1204
1205 do { /* For all sections */
1206 u32 sz;
1207
1208 if (!sect_rest) {
1209 sect_rest = msg_sect[++curr_sect].iov_len;
1210 sect_crs = (const unchar *)msg_sect[curr_sect].iov_base;
1211 }
1212
1213 if (sect_rest < fragm_rest)
1214 sz = sect_rest;
1215 else
1216 sz = fragm_rest;
1217
1218 if (copy_from_user(buf->data + fragm_crs, sect_crs, sz)) {
1219 res = -EFAULT;
1220 error:
1221 for (; buf_chain; buf_chain = buf) {
1222 buf = buf_chain->next;
1223 kfree_skb(buf_chain);
1224 }
1225 return res;
1226 }
1227 sect_crs += sz;
1228 sect_rest -= sz;
1229 fragm_crs += sz;
1230 fragm_rest -= sz;
1231 rest -= sz;
1232
1233 if (!fragm_rest && rest) {
1234
1235 /* Initiate new fragment: */
1236 if (rest <= fragm_sz) {
1237 fragm_sz = rest;
1238 msg_set_type(&fragm_hdr, LAST_FRAGMENT);
1239 } else {
1240 msg_set_type(&fragm_hdr, FRAGMENT);
1241 }
1242 msg_set_size(&fragm_hdr, fragm_sz + INT_H_SIZE);
1243 msg_set_fragm_no(&fragm_hdr, ++fragm_no);
1244 prev = buf;
1245 buf = tipc_buf_acquire(fragm_sz + INT_H_SIZE);
1246 if (!buf) {
1247 res = -ENOMEM;
1248 goto error;
1249 }
1250
1251 buf->next = NULL;
1252 prev->next = buf;
1253 skb_copy_to_linear_data(buf, &fragm_hdr, INT_H_SIZE);
1254 fragm_crs = INT_H_SIZE;
1255 fragm_rest = fragm_sz;
1256 }
1257 } while (rest > 0);
1258
1259 /*
1260 * Now we have a buffer chain. Select a link and check
1261 * that packet size is still OK
1262 */
1263 node = tipc_node_find(destaddr);
1264 if (likely(node)) {
1265 tipc_node_lock(node);
1266 l_ptr = node->active_links[sender->ref & 1];
1267 if (!l_ptr) {
1268 tipc_node_unlock(node);
1269 goto reject;
1270 }
1271 if (l_ptr->max_pkt < max_pkt) {
1272 sender->max_pkt = l_ptr->max_pkt;
1273 tipc_node_unlock(node);
1274 for (; buf_chain; buf_chain = buf) {
1275 buf = buf_chain->next;
1276 kfree_skb(buf_chain);
1277 }
1278 goto again;
1279 }
1280 } else {
1281 reject:
1282 for (; buf_chain; buf_chain = buf) {
1283 buf = buf_chain->next;
1284 kfree_skb(buf_chain);
1285 }
1286 return tipc_port_reject_sections(sender, hdr, msg_sect, num_sect,
1287 total_len, TIPC_ERR_NO_NODE);
1288 }
1289
1290 /* Append chain of fragments to send queue & send them */
1291 l_ptr->long_msg_seq_no++;
1292 link_add_chain_to_outqueue(l_ptr, buf_chain, l_ptr->long_msg_seq_no);
1293 l_ptr->stats.sent_fragments += fragm_no;
1294 l_ptr->stats.sent_fragmented++;
1295 tipc_link_push_queue(l_ptr);
1296 tipc_node_unlock(node);
1297 return dsz;
1298 }
1299
1300 /*
1301 * tipc_link_push_packet: Push one unsent packet to the media
1302 */
1303 u32 tipc_link_push_packet(struct tipc_link *l_ptr)
1304 {
1305 struct sk_buff *buf = l_ptr->first_out;
1306 u32 r_q_size = l_ptr->retransm_queue_size;
1307 u32 r_q_head = l_ptr->retransm_queue_head;
1308
1309 /* Step to position where retransmission failed, if any, */
1310 /* consider that buffers may have been released in meantime */
1311 if (r_q_size && buf) {
1312 u32 last = lesser(mod(r_q_head + r_q_size),
1313 link_last_sent(l_ptr));
1314 u32 first = buf_seqno(buf);
1315
1316 while (buf && less(first, r_q_head)) {
1317 first = mod(first + 1);
1318 buf = buf->next;
1319 }
1320 l_ptr->retransm_queue_head = r_q_head = first;
1321 l_ptr->retransm_queue_size = r_q_size = mod(last - first);
1322 }
1323
1324 /* Continue retransmission now, if there is anything: */
1325 if (r_q_size && buf) {
1326 msg_set_ack(buf_msg(buf), mod(l_ptr->next_in_no - 1));
1327 msg_set_bcast_ack(buf_msg(buf), l_ptr->owner->bclink.last_in);
1328 tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr);
1329 l_ptr->retransm_queue_head = mod(++r_q_head);
1330 l_ptr->retransm_queue_size = --r_q_size;
1331 l_ptr->stats.retransmitted++;
1332 return 0;
1333 }
1334
1335 /* Send deferred protocol message, if any: */
1336 buf = l_ptr->proto_msg_queue;
1337 if (buf) {
1338 msg_set_ack(buf_msg(buf), mod(l_ptr->next_in_no - 1));
1339 msg_set_bcast_ack(buf_msg(buf), l_ptr->owner->bclink.last_in);
1340 tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr);
1341 l_ptr->unacked_window = 0;
1342 kfree_skb(buf);
1343 l_ptr->proto_msg_queue = NULL;
1344 return 0;
1345 }
1346
1347 /* Send one deferred data message, if send window not full: */
1348 buf = l_ptr->next_out;
1349 if (buf) {
1350 struct tipc_msg *msg = buf_msg(buf);
1351 u32 next = msg_seqno(msg);
1352 u32 first = buf_seqno(l_ptr->first_out);
1353
1354 if (mod(next - first) < l_ptr->queue_limit[0]) {
1355 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
1356 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1357 tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr);
1358 if (msg_user(msg) == MSG_BUNDLER)
1359 msg_set_type(msg, CLOSED_MSG);
1360 l_ptr->next_out = buf->next;
1361 return 0;
1362 }
1363 }
1364 return 1;
1365 }
1366
1367 /*
1368 * push_queue(): push out the unsent messages of a link where
1369 * congestion has abated. Node is locked
1370 */
1371 void tipc_link_push_queue(struct tipc_link *l_ptr)
1372 {
1373 u32 res;
1374
1375 if (tipc_bearer_blocked(l_ptr->b_ptr))
1376 return;
1377
1378 do {
1379 res = tipc_link_push_packet(l_ptr);
1380 } while (!res);
1381 }
1382
1383 static void link_reset_all(unsigned long addr)
1384 {
1385 struct tipc_node *n_ptr;
1386 char addr_string[16];
1387 u32 i;
1388
1389 read_lock_bh(&tipc_net_lock);
1390 n_ptr = tipc_node_find((u32)addr);
1391 if (!n_ptr) {
1392 read_unlock_bh(&tipc_net_lock);
1393 return; /* node no longer exists */
1394 }
1395
1396 tipc_node_lock(n_ptr);
1397
1398 pr_warn("Resetting all links to %s\n",
1399 tipc_addr_string_fill(addr_string, n_ptr->addr));
1400
1401 for (i = 0; i < MAX_BEARERS; i++) {
1402 if (n_ptr->links[i]) {
1403 link_print(n_ptr->links[i], "Resetting link\n");
1404 tipc_link_reset(n_ptr->links[i]);
1405 }
1406 }
1407
1408 tipc_node_unlock(n_ptr);
1409 read_unlock_bh(&tipc_net_lock);
1410 }
1411
1412 static void link_retransmit_failure(struct tipc_link *l_ptr,
1413 struct sk_buff *buf)
1414 {
1415 struct tipc_msg *msg = buf_msg(buf);
1416
1417 pr_warn("Retransmission failure on link <%s>\n", l_ptr->name);
1418
1419 if (l_ptr->addr) {
1420 /* Handle failure on standard link */
1421 link_print(l_ptr, "Resetting link\n");
1422 tipc_link_reset(l_ptr);
1423
1424 } else {
1425 /* Handle failure on broadcast link */
1426 struct tipc_node *n_ptr;
1427 char addr_string[16];
1428
1429 pr_info("Msg seq number: %u, ", msg_seqno(msg));
1430 pr_cont("Outstanding acks: %lu\n",
1431 (unsigned long) TIPC_SKB_CB(buf)->handle);
1432
1433 n_ptr = tipc_bclink_retransmit_to();
1434 tipc_node_lock(n_ptr);
1435
1436 tipc_addr_string_fill(addr_string, n_ptr->addr);
1437 pr_info("Broadcast link info for %s\n", addr_string);
1438 pr_info("Reception permitted: %d, Acked: %u\n",
1439 n_ptr->bclink.recv_permitted,
1440 n_ptr->bclink.acked);
1441 pr_info("Last in: %u, Oos state: %u, Last sent: %u\n",
1442 n_ptr->bclink.last_in,
1443 n_ptr->bclink.oos_state,
1444 n_ptr->bclink.last_sent);
1445
1446 tipc_k_signal((Handler)link_reset_all, (unsigned long)n_ptr->addr);
1447
1448 tipc_node_unlock(n_ptr);
1449
1450 l_ptr->stale_count = 0;
1451 }
1452 }
1453
1454 void tipc_link_retransmit(struct tipc_link *l_ptr, struct sk_buff *buf,
1455 u32 retransmits)
1456 {
1457 struct tipc_msg *msg;
1458
1459 if (!buf)
1460 return;
1461
1462 msg = buf_msg(buf);
1463
1464 if (tipc_bearer_blocked(l_ptr->b_ptr)) {
1465 if (l_ptr->retransm_queue_size == 0) {
1466 l_ptr->retransm_queue_head = msg_seqno(msg);
1467 l_ptr->retransm_queue_size = retransmits;
1468 } else {
1469 pr_err("Unexpected retransmit on link %s (qsize=%d)\n",
1470 l_ptr->name, l_ptr->retransm_queue_size);
1471 }
1472 return;
1473 } else {
1474 /* Detect repeated retransmit failures on unblocked bearer */
1475 if (l_ptr->last_retransmitted == msg_seqno(msg)) {
1476 if (++l_ptr->stale_count > 100) {
1477 link_retransmit_failure(l_ptr, buf);
1478 return;
1479 }
1480 } else {
1481 l_ptr->last_retransmitted = msg_seqno(msg);
1482 l_ptr->stale_count = 1;
1483 }
1484 }
1485
1486 while (retransmits && (buf != l_ptr->next_out) && buf) {
1487 msg = buf_msg(buf);
1488 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
1489 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1490 tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr);
1491 buf = buf->next;
1492 retransmits--;
1493 l_ptr->stats.retransmitted++;
1494 }
1495
1496 l_ptr->retransm_queue_head = l_ptr->retransm_queue_size = 0;
1497 }
1498
1499 /**
1500 * link_insert_deferred_queue - insert deferred messages back into receive chain
1501 */
1502 static struct sk_buff *link_insert_deferred_queue(struct tipc_link *l_ptr,
1503 struct sk_buff *buf)
1504 {
1505 u32 seq_no;
1506
1507 if (l_ptr->oldest_deferred_in == NULL)
1508 return buf;
1509
1510 seq_no = buf_seqno(l_ptr->oldest_deferred_in);
1511 if (seq_no == mod(l_ptr->next_in_no)) {
1512 l_ptr->newest_deferred_in->next = buf;
1513 buf = l_ptr->oldest_deferred_in;
1514 l_ptr->oldest_deferred_in = NULL;
1515 l_ptr->deferred_inqueue_sz = 0;
1516 }
1517 return buf;
1518 }
1519
1520 /**
1521 * link_recv_buf_validate - validate basic format of received message
1522 *
1523 * This routine ensures a TIPC message has an acceptable header, and at least
1524 * as much data as the header indicates it should. The routine also ensures
1525 * that the entire message header is stored in the main fragment of the message
1526 * buffer, to simplify future access to message header fields.
1527 *
1528 * Note: Having extra info present in the message header or data areas is OK.
1529 * TIPC will ignore the excess, under the assumption that it is optional info
1530 * introduced by a later release of the protocol.
1531 */
1532 static int link_recv_buf_validate(struct sk_buff *buf)
1533 {
1534 static u32 min_data_hdr_size[8] = {
1535 SHORT_H_SIZE, MCAST_H_SIZE, NAMED_H_SIZE, BASIC_H_SIZE,
1536 MAX_H_SIZE, MAX_H_SIZE, MAX_H_SIZE, MAX_H_SIZE
1537 };
1538
1539 struct tipc_msg *msg;
1540 u32 tipc_hdr[2];
1541 u32 size;
1542 u32 hdr_size;
1543 u32 min_hdr_size;
1544
1545 if (unlikely(buf->len < MIN_H_SIZE))
1546 return 0;
1547
1548 msg = skb_header_pointer(buf, 0, sizeof(tipc_hdr), tipc_hdr);
1549 if (msg == NULL)
1550 return 0;
1551
1552 if (unlikely(msg_version(msg) != TIPC_VERSION))
1553 return 0;
1554
1555 size = msg_size(msg);
1556 hdr_size = msg_hdr_sz(msg);
1557 min_hdr_size = msg_isdata(msg) ?
1558 min_data_hdr_size[msg_type(msg)] : INT_H_SIZE;
1559
1560 if (unlikely((hdr_size < min_hdr_size) ||
1561 (size < hdr_size) ||
1562 (buf->len < size) ||
1563 (size - hdr_size > TIPC_MAX_USER_MSG_SIZE)))
1564 return 0;
1565
1566 return pskb_may_pull(buf, hdr_size);
1567 }
1568
1569 /**
1570 * tipc_recv_msg - process TIPC messages arriving from off-node
1571 * @head: pointer to message buffer chain
1572 * @tb_ptr: pointer to bearer message arrived on
1573 *
1574 * Invoked with no locks held. Bearer pointer must point to a valid bearer
1575 * structure (i.e. cannot be NULL), but bearer can be inactive.
1576 */
1577 void tipc_recv_msg(struct sk_buff *head, struct tipc_bearer *b_ptr)
1578 {
1579 read_lock_bh(&tipc_net_lock);
1580 while (head) {
1581 struct tipc_node *n_ptr;
1582 struct tipc_link *l_ptr;
1583 struct sk_buff *crs;
1584 struct sk_buff *buf = head;
1585 struct tipc_msg *msg;
1586 u32 seq_no;
1587 u32 ackd;
1588 u32 released = 0;
1589 int type;
1590
1591 head = head->next;
1592
1593 /* Ensure bearer is still enabled */
1594 if (unlikely(!b_ptr->active))
1595 goto cont;
1596
1597 /* Ensure message is well-formed */
1598 if (unlikely(!link_recv_buf_validate(buf)))
1599 goto cont;
1600
1601 /* Ensure message data is a single contiguous unit */
1602 if (unlikely(skb_linearize(buf)))
1603 goto cont;
1604
1605 /* Handle arrival of a non-unicast link message */
1606 msg = buf_msg(buf);
1607
1608 if (unlikely(msg_non_seq(msg))) {
1609 if (msg_user(msg) == LINK_CONFIG)
1610 tipc_disc_recv_msg(buf, b_ptr);
1611 else
1612 tipc_bclink_recv_pkt(buf);
1613 continue;
1614 }
1615
1616 /* Discard unicast link messages destined for another node */
1617 if (unlikely(!msg_short(msg) &&
1618 (msg_destnode(msg) != tipc_own_addr)))
1619 goto cont;
1620
1621 /* Locate neighboring node that sent message */
1622 n_ptr = tipc_node_find(msg_prevnode(msg));
1623 if (unlikely(!n_ptr))
1624 goto cont;
1625 tipc_node_lock(n_ptr);
1626
1627 /* Locate unicast link endpoint that should handle message */
1628 l_ptr = n_ptr->links[b_ptr->identity];
1629 if (unlikely(!l_ptr)) {
1630 tipc_node_unlock(n_ptr);
1631 goto cont;
1632 }
1633
1634 /* Verify that communication with node is currently allowed */
1635 if ((n_ptr->block_setup & WAIT_PEER_DOWN) &&
1636 msg_user(msg) == LINK_PROTOCOL &&
1637 (msg_type(msg) == RESET_MSG ||
1638 msg_type(msg) == ACTIVATE_MSG) &&
1639 !msg_redundant_link(msg))
1640 n_ptr->block_setup &= ~WAIT_PEER_DOWN;
1641
1642 if (n_ptr->block_setup) {
1643 tipc_node_unlock(n_ptr);
1644 goto cont;
1645 }
1646
1647 /* Validate message sequence number info */
1648 seq_no = msg_seqno(msg);
1649 ackd = msg_ack(msg);
1650
1651 /* Release acked messages */
1652 if (n_ptr->bclink.recv_permitted)
1653 tipc_bclink_acknowledge(n_ptr, msg_bcast_ack(msg));
1654
1655 crs = l_ptr->first_out;
1656 while ((crs != l_ptr->next_out) &&
1657 less_eq(buf_seqno(crs), ackd)) {
1658 struct sk_buff *next = crs->next;
1659
1660 kfree_skb(crs);
1661 crs = next;
1662 released++;
1663 }
1664 if (released) {
1665 l_ptr->first_out = crs;
1666 l_ptr->out_queue_size -= released;
1667 }
1668
1669 /* Try sending any messages link endpoint has pending */
1670 if (unlikely(l_ptr->next_out))
1671 tipc_link_push_queue(l_ptr);
1672 if (unlikely(!list_empty(&l_ptr->waiting_ports)))
1673 tipc_link_wakeup_ports(l_ptr, 0);
1674 if (unlikely(++l_ptr->unacked_window >= TIPC_MIN_LINK_WIN)) {
1675 l_ptr->stats.sent_acks++;
1676 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, 0, 0);
1677 }
1678
1679 /* Now (finally!) process the incoming message */
1680 protocol_check:
1681 if (likely(link_working_working(l_ptr))) {
1682 if (likely(seq_no == mod(l_ptr->next_in_no))) {
1683 l_ptr->next_in_no++;
1684 if (unlikely(l_ptr->oldest_deferred_in))
1685 head = link_insert_deferred_queue(l_ptr,
1686 head);
1687 deliver:
1688 if (likely(msg_isdata(msg))) {
1689 tipc_node_unlock(n_ptr);
1690 tipc_port_recv_msg(buf);
1691 continue;
1692 }
1693 switch (msg_user(msg)) {
1694 int ret;
1695 case MSG_BUNDLER:
1696 l_ptr->stats.recv_bundles++;
1697 l_ptr->stats.recv_bundled +=
1698 msg_msgcnt(msg);
1699 tipc_node_unlock(n_ptr);
1700 tipc_link_recv_bundle(buf);
1701 continue;
1702 case NAME_DISTRIBUTOR:
1703 n_ptr->bclink.recv_permitted = true;
1704 tipc_node_unlock(n_ptr);
1705 tipc_named_recv(buf);
1706 continue;
1707 case BCAST_PROTOCOL:
1708 tipc_link_recv_sync(n_ptr, buf);
1709 tipc_node_unlock(n_ptr);
1710 continue;
1711 case CONN_MANAGER:
1712 tipc_node_unlock(n_ptr);
1713 tipc_port_recv_proto_msg(buf);
1714 continue;
1715 case MSG_FRAGMENTER:
1716 l_ptr->stats.recv_fragments++;
1717 ret = tipc_link_recv_fragment(
1718 &l_ptr->defragm_buf,
1719 &buf, &msg);
1720 if (ret == 1) {
1721 l_ptr->stats.recv_fragmented++;
1722 goto deliver;
1723 }
1724 if (ret == -1)
1725 l_ptr->next_in_no--;
1726 break;
1727 case CHANGEOVER_PROTOCOL:
1728 type = msg_type(msg);
1729 if (link_recv_changeover_msg(&l_ptr,
1730 &buf)) {
1731 msg = buf_msg(buf);
1732 seq_no = msg_seqno(msg);
1733 if (type == ORIGINAL_MSG)
1734 goto deliver;
1735 goto protocol_check;
1736 }
1737 break;
1738 default:
1739 kfree_skb(buf);
1740 buf = NULL;
1741 break;
1742 }
1743 tipc_node_unlock(n_ptr);
1744 tipc_net_route_msg(buf);
1745 continue;
1746 }
1747 link_handle_out_of_seq_msg(l_ptr, buf);
1748 head = link_insert_deferred_queue(l_ptr, head);
1749 tipc_node_unlock(n_ptr);
1750 continue;
1751 }
1752
1753 /* Link is not in state WORKING_WORKING */
1754 if (msg_user(msg) == LINK_PROTOCOL) {
1755 link_recv_proto_msg(l_ptr, buf);
1756 head = link_insert_deferred_queue(l_ptr, head);
1757 tipc_node_unlock(n_ptr);
1758 continue;
1759 }
1760
1761 /* Traffic message. Conditionally activate link */
1762 link_state_event(l_ptr, TRAFFIC_MSG_EVT);
1763
1764 if (link_working_working(l_ptr)) {
1765 /* Re-insert buffer in front of queue */
1766 buf->next = head;
1767 head = buf;
1768 tipc_node_unlock(n_ptr);
1769 continue;
1770 }
1771 tipc_node_unlock(n_ptr);
1772 cont:
1773 kfree_skb(buf);
1774 }
1775 read_unlock_bh(&tipc_net_lock);
1776 }
1777
1778 /**
1779 * tipc_link_defer_pkt - Add out-of-sequence message to deferred reception queue
1780 *
1781 * Returns increase in queue length (i.e. 0 or 1)
1782 */
1783 u32 tipc_link_defer_pkt(struct sk_buff **head, struct sk_buff **tail,
1784 struct sk_buff *buf)
1785 {
1786 struct sk_buff *queue_buf;
1787 struct sk_buff **prev;
1788 u32 seq_no = buf_seqno(buf);
1789
1790 buf->next = NULL;
1791
1792 /* Empty queue ? */
1793 if (*head == NULL) {
1794 *head = *tail = buf;
1795 return 1;
1796 }
1797
1798 /* Last ? */
1799 if (less(buf_seqno(*tail), seq_no)) {
1800 (*tail)->next = buf;
1801 *tail = buf;
1802 return 1;
1803 }
1804
1805 /* Locate insertion point in queue, then insert; discard if duplicate */
1806 prev = head;
1807 queue_buf = *head;
1808 for (;;) {
1809 u32 curr_seqno = buf_seqno(queue_buf);
1810
1811 if (seq_no == curr_seqno) {
1812 kfree_skb(buf);
1813 return 0;
1814 }
1815
1816 if (less(seq_no, curr_seqno))
1817 break;
1818
1819 prev = &queue_buf->next;
1820 queue_buf = queue_buf->next;
1821 }
1822
1823 buf->next = queue_buf;
1824 *prev = buf;
1825 return 1;
1826 }
1827
1828 /*
1829 * link_handle_out_of_seq_msg - handle arrival of out-of-sequence packet
1830 */
1831 static void link_handle_out_of_seq_msg(struct tipc_link *l_ptr,
1832 struct sk_buff *buf)
1833 {
1834 u32 seq_no = buf_seqno(buf);
1835
1836 if (likely(msg_user(buf_msg(buf)) == LINK_PROTOCOL)) {
1837 link_recv_proto_msg(l_ptr, buf);
1838 return;
1839 }
1840
1841 /* Record OOS packet arrival (force mismatch on next timeout) */
1842 l_ptr->checkpoint--;
1843
1844 /*
1845 * Discard packet if a duplicate; otherwise add it to deferred queue
1846 * and notify peer of gap as per protocol specification
1847 */
1848 if (less(seq_no, mod(l_ptr->next_in_no))) {
1849 l_ptr->stats.duplicates++;
1850 kfree_skb(buf);
1851 return;
1852 }
1853
1854 if (tipc_link_defer_pkt(&l_ptr->oldest_deferred_in,
1855 &l_ptr->newest_deferred_in, buf)) {
1856 l_ptr->deferred_inqueue_sz++;
1857 l_ptr->stats.deferred_recv++;
1858 if ((l_ptr->deferred_inqueue_sz % 16) == 1)
1859 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, 0, 0);
1860 } else
1861 l_ptr->stats.duplicates++;
1862 }
1863
1864 /*
1865 * Send protocol message to the other endpoint.
1866 */
1867 void tipc_link_send_proto_msg(struct tipc_link *l_ptr, u32 msg_typ,
1868 int probe_msg, u32 gap, u32 tolerance,
1869 u32 priority, u32 ack_mtu)
1870 {
1871 struct sk_buff *buf = NULL;
1872 struct tipc_msg *msg = l_ptr->pmsg;
1873 u32 msg_size = sizeof(l_ptr->proto_msg);
1874 int r_flag;
1875
1876 /* Discard any previous message that was deferred due to congestion */
1877 if (l_ptr->proto_msg_queue) {
1878 kfree_skb(l_ptr->proto_msg_queue);
1879 l_ptr->proto_msg_queue = NULL;
1880 }
1881
1882 if (link_blocked(l_ptr))
1883 return;
1884
1885 /* Abort non-RESET send if communication with node is prohibited */
1886 if ((l_ptr->owner->block_setup) && (msg_typ != RESET_MSG))
1887 return;
1888
1889 /* Create protocol message with "out-of-sequence" sequence number */
1890 msg_set_type(msg, msg_typ);
1891 msg_set_net_plane(msg, l_ptr->b_ptr->net_plane);
1892 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1893 msg_set_last_bcast(msg, tipc_bclink_get_last_sent());
1894
1895 if (msg_typ == STATE_MSG) {
1896 u32 next_sent = mod(l_ptr->next_out_no);
1897
1898 if (!tipc_link_is_up(l_ptr))
1899 return;
1900 if (l_ptr->next_out)
1901 next_sent = buf_seqno(l_ptr->next_out);
1902 msg_set_next_sent(msg, next_sent);
1903 if (l_ptr->oldest_deferred_in) {
1904 u32 rec = buf_seqno(l_ptr->oldest_deferred_in);
1905 gap = mod(rec - mod(l_ptr->next_in_no));
1906 }
1907 msg_set_seq_gap(msg, gap);
1908 if (gap)
1909 l_ptr->stats.sent_nacks++;
1910 msg_set_link_tolerance(msg, tolerance);
1911 msg_set_linkprio(msg, priority);
1912 msg_set_max_pkt(msg, ack_mtu);
1913 msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
1914 msg_set_probe(msg, probe_msg != 0);
1915 if (probe_msg) {
1916 u32 mtu = l_ptr->max_pkt;
1917
1918 if ((mtu < l_ptr->max_pkt_target) &&
1919 link_working_working(l_ptr) &&
1920 l_ptr->fsm_msg_cnt) {
1921 msg_size = (mtu + (l_ptr->max_pkt_target - mtu)/2 + 2) & ~3;
1922 if (l_ptr->max_pkt_probes == 10) {
1923 l_ptr->max_pkt_target = (msg_size - 4);
1924 l_ptr->max_pkt_probes = 0;
1925 msg_size = (mtu + (l_ptr->max_pkt_target - mtu)/2 + 2) & ~3;
1926 }
1927 l_ptr->max_pkt_probes++;
1928 }
1929
1930 l_ptr->stats.sent_probes++;
1931 }
1932 l_ptr->stats.sent_states++;
1933 } else { /* RESET_MSG or ACTIVATE_MSG */
1934 msg_set_ack(msg, mod(l_ptr->reset_checkpoint - 1));
1935 msg_set_seq_gap(msg, 0);
1936 msg_set_next_sent(msg, 1);
1937 msg_set_probe(msg, 0);
1938 msg_set_link_tolerance(msg, l_ptr->tolerance);
1939 msg_set_linkprio(msg, l_ptr->priority);
1940 msg_set_max_pkt(msg, l_ptr->max_pkt_target);
1941 }
1942
1943 r_flag = (l_ptr->owner->working_links > tipc_link_is_up(l_ptr));
1944 msg_set_redundant_link(msg, r_flag);
1945 msg_set_linkprio(msg, l_ptr->priority);
1946 msg_set_size(msg, msg_size);
1947
1948 msg_set_seqno(msg, mod(l_ptr->next_out_no + (0xffff/2)));
1949
1950 buf = tipc_buf_acquire(msg_size);
1951 if (!buf)
1952 return;
1953
1954 skb_copy_to_linear_data(buf, msg, sizeof(l_ptr->proto_msg));
1955 buf->priority = TC_PRIO_CONTROL;
1956
1957 /* Defer message if bearer is already blocked */
1958 if (tipc_bearer_blocked(l_ptr->b_ptr)) {
1959 l_ptr->proto_msg_queue = buf;
1960 return;
1961 }
1962
1963 tipc_bearer_send(l_ptr->b_ptr, buf, &l_ptr->media_addr);
1964 l_ptr->unacked_window = 0;
1965 kfree_skb(buf);
1966 }
1967
1968 /*
1969 * Receive protocol message :
1970 * Note that network plane id propagates through the network, and may
1971 * change at any time. The node with lowest address rules
1972 */
1973 static void link_recv_proto_msg(struct tipc_link *l_ptr, struct sk_buff *buf)
1974 {
1975 u32 rec_gap = 0;
1976 u32 max_pkt_info;
1977 u32 max_pkt_ack;
1978 u32 msg_tol;
1979 struct tipc_msg *msg = buf_msg(buf);
1980
1981 if (link_blocked(l_ptr))
1982 goto exit;
1983
1984 /* record unnumbered packet arrival (force mismatch on next timeout) */
1985 l_ptr->checkpoint--;
1986
1987 if (l_ptr->b_ptr->net_plane != msg_net_plane(msg))
1988 if (tipc_own_addr > msg_prevnode(msg))
1989 l_ptr->b_ptr->net_plane = msg_net_plane(msg);
1990
1991 l_ptr->owner->permit_changeover = msg_redundant_link(msg);
1992
1993 switch (msg_type(msg)) {
1994
1995 case RESET_MSG:
1996 if (!link_working_unknown(l_ptr) &&
1997 (l_ptr->peer_session != INVALID_SESSION)) {
1998 if (less_eq(msg_session(msg), l_ptr->peer_session))
1999 break; /* duplicate or old reset: ignore */
2000 }
2001
2002 if (!msg_redundant_link(msg) && (link_working_working(l_ptr) ||
2003 link_working_unknown(l_ptr))) {
2004 /*
2005 * peer has lost contact -- don't allow peer's links
2006 * to reactivate before we recognize loss & clean up
2007 */
2008 l_ptr->owner->block_setup = WAIT_NODE_DOWN;
2009 }
2010
2011 link_state_event(l_ptr, RESET_MSG);
2012
2013 /* fall thru' */
2014 case ACTIVATE_MSG:
2015 /* Update link settings according other endpoint's values */
2016 strcpy((strrchr(l_ptr->name, ':') + 1), (char *)msg_data(msg));
2017
2018 msg_tol = msg_link_tolerance(msg);
2019 if (msg_tol > l_ptr->tolerance)
2020 link_set_supervision_props(l_ptr, msg_tol);
2021
2022 if (msg_linkprio(msg) > l_ptr->priority)
2023 l_ptr->priority = msg_linkprio(msg);
2024
2025 max_pkt_info = msg_max_pkt(msg);
2026 if (max_pkt_info) {
2027 if (max_pkt_info < l_ptr->max_pkt_target)
2028 l_ptr->max_pkt_target = max_pkt_info;
2029 if (l_ptr->max_pkt > l_ptr->max_pkt_target)
2030 l_ptr->max_pkt = l_ptr->max_pkt_target;
2031 } else {
2032 l_ptr->max_pkt = l_ptr->max_pkt_target;
2033 }
2034
2035 /* Synchronize broadcast link info, if not done previously */
2036 if (!tipc_node_is_up(l_ptr->owner)) {
2037 l_ptr->owner->bclink.last_sent =
2038 l_ptr->owner->bclink.last_in =
2039 msg_last_bcast(msg);
2040 l_ptr->owner->bclink.oos_state = 0;
2041 }
2042
2043 l_ptr->peer_session = msg_session(msg);
2044 l_ptr->peer_bearer_id = msg_bearer_id(msg);
2045
2046 if (msg_type(msg) == ACTIVATE_MSG)
2047 link_state_event(l_ptr, ACTIVATE_MSG);
2048 break;
2049 case STATE_MSG:
2050
2051 msg_tol = msg_link_tolerance(msg);
2052 if (msg_tol)
2053 link_set_supervision_props(l_ptr, msg_tol);
2054
2055 if (msg_linkprio(msg) &&
2056 (msg_linkprio(msg) != l_ptr->priority)) {
2057 pr_warn("%s<%s>, priority change %u->%u\n",
2058 link_rst_msg, l_ptr->name, l_ptr->priority,
2059 msg_linkprio(msg));
2060 l_ptr->priority = msg_linkprio(msg);
2061 tipc_link_reset(l_ptr); /* Enforce change to take effect */
2062 break;
2063 }
2064 link_state_event(l_ptr, TRAFFIC_MSG_EVT);
2065 l_ptr->stats.recv_states++;
2066 if (link_reset_unknown(l_ptr))
2067 break;
2068
2069 if (less_eq(mod(l_ptr->next_in_no), msg_next_sent(msg))) {
2070 rec_gap = mod(msg_next_sent(msg) -
2071 mod(l_ptr->next_in_no));
2072 }
2073
2074 max_pkt_ack = msg_max_pkt(msg);
2075 if (max_pkt_ack > l_ptr->max_pkt) {
2076 l_ptr->max_pkt = max_pkt_ack;
2077 l_ptr->max_pkt_probes = 0;
2078 }
2079
2080 max_pkt_ack = 0;
2081 if (msg_probe(msg)) {
2082 l_ptr->stats.recv_probes++;
2083 if (msg_size(msg) > sizeof(l_ptr->proto_msg))
2084 max_pkt_ack = msg_size(msg);
2085 }
2086
2087 /* Protocol message before retransmits, reduce loss risk */
2088 if (l_ptr->owner->bclink.recv_permitted)
2089 tipc_bclink_update_link_state(l_ptr->owner,
2090 msg_last_bcast(msg));
2091
2092 if (rec_gap || (msg_probe(msg))) {
2093 tipc_link_send_proto_msg(l_ptr, STATE_MSG,
2094 0, rec_gap, 0, 0, max_pkt_ack);
2095 }
2096 if (msg_seq_gap(msg)) {
2097 l_ptr->stats.recv_nacks++;
2098 tipc_link_retransmit(l_ptr, l_ptr->first_out,
2099 msg_seq_gap(msg));
2100 }
2101 break;
2102 }
2103 exit:
2104 kfree_skb(buf);
2105 }
2106
2107
2108 /*
2109 * tipc_link_tunnel(): Send one message via a link belonging to
2110 * another bearer. Owner node is locked.
2111 */
2112 static void tipc_link_tunnel(struct tipc_link *l_ptr,
2113 struct tipc_msg *tunnel_hdr, struct tipc_msg *msg,
2114 u32 selector)
2115 {
2116 struct tipc_link *tunnel;
2117 struct sk_buff *buf;
2118 u32 length = msg_size(msg);
2119
2120 tunnel = l_ptr->owner->active_links[selector & 1];
2121 if (!tipc_link_is_up(tunnel)) {
2122 pr_warn("%stunnel link no longer available\n", link_co_err);
2123 return;
2124 }
2125 msg_set_size(tunnel_hdr, length + INT_H_SIZE);
2126 buf = tipc_buf_acquire(length + INT_H_SIZE);
2127 if (!buf) {
2128 pr_warn("%sunable to send tunnel msg\n", link_co_err);
2129 return;
2130 }
2131 skb_copy_to_linear_data(buf, tunnel_hdr, INT_H_SIZE);
2132 skb_copy_to_linear_data_offset(buf, INT_H_SIZE, msg, length);
2133 tipc_link_send_buf(tunnel, buf);
2134 }
2135
2136
2137
2138 /*
2139 * changeover(): Send whole message queue via the remaining link
2140 * Owner node is locked.
2141 */
2142 void tipc_link_changeover(struct tipc_link *l_ptr)
2143 {
2144 u32 msgcount = l_ptr->out_queue_size;
2145 struct sk_buff *crs = l_ptr->first_out;
2146 struct tipc_link *tunnel = l_ptr->owner->active_links[0];
2147 struct tipc_msg tunnel_hdr;
2148 int split_bundles;
2149
2150 if (!tunnel)
2151 return;
2152
2153 if (!l_ptr->owner->permit_changeover) {
2154 pr_warn("%speer did not permit changeover\n", link_co_err);
2155 return;
2156 }
2157
2158 tipc_msg_init(&tunnel_hdr, CHANGEOVER_PROTOCOL,
2159 ORIGINAL_MSG, INT_H_SIZE, l_ptr->addr);
2160 msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id);
2161 msg_set_msgcnt(&tunnel_hdr, msgcount);
2162
2163 if (!l_ptr->first_out) {
2164 struct sk_buff *buf;
2165
2166 buf = tipc_buf_acquire(INT_H_SIZE);
2167 if (buf) {
2168 skb_copy_to_linear_data(buf, &tunnel_hdr, INT_H_SIZE);
2169 msg_set_size(&tunnel_hdr, INT_H_SIZE);
2170 tipc_link_send_buf(tunnel, buf);
2171 } else {
2172 pr_warn("%sunable to send changeover msg\n",
2173 link_co_err);
2174 }
2175 return;
2176 }
2177
2178 split_bundles = (l_ptr->owner->active_links[0] !=
2179 l_ptr->owner->active_links[1]);
2180
2181 while (crs) {
2182 struct tipc_msg *msg = buf_msg(crs);
2183
2184 if ((msg_user(msg) == MSG_BUNDLER) && split_bundles) {
2185 struct tipc_msg *m = msg_get_wrapped(msg);
2186 unchar *pos = (unchar *)m;
2187
2188 msgcount = msg_msgcnt(msg);
2189 while (msgcount--) {
2190 msg_set_seqno(m, msg_seqno(msg));
2191 tipc_link_tunnel(l_ptr, &tunnel_hdr, m,
2192 msg_link_selector(m));
2193 pos += align(msg_size(m));
2194 m = (struct tipc_msg *)pos;
2195 }
2196 } else {
2197 tipc_link_tunnel(l_ptr, &tunnel_hdr, msg,
2198 msg_link_selector(msg));
2199 }
2200 crs = crs->next;
2201 }
2202 }
2203
2204 void tipc_link_send_duplicate(struct tipc_link *l_ptr, struct tipc_link *tunnel)
2205 {
2206 struct sk_buff *iter;
2207 struct tipc_msg tunnel_hdr;
2208
2209 tipc_msg_init(&tunnel_hdr, CHANGEOVER_PROTOCOL,
2210 DUPLICATE_MSG, INT_H_SIZE, l_ptr->addr);
2211 msg_set_msgcnt(&tunnel_hdr, l_ptr->out_queue_size);
2212 msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id);
2213 iter = l_ptr->first_out;
2214 while (iter) {
2215 struct sk_buff *outbuf;
2216 struct tipc_msg *msg = buf_msg(iter);
2217 u32 length = msg_size(msg);
2218
2219 if (msg_user(msg) == MSG_BUNDLER)
2220 msg_set_type(msg, CLOSED_MSG);
2221 msg_set_ack(msg, mod(l_ptr->next_in_no - 1)); /* Update */
2222 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
2223 msg_set_size(&tunnel_hdr, length + INT_H_SIZE);
2224 outbuf = tipc_buf_acquire(length + INT_H_SIZE);
2225 if (outbuf == NULL) {
2226 pr_warn("%sunable to send duplicate msg\n",
2227 link_co_err);
2228 return;
2229 }
2230 skb_copy_to_linear_data(outbuf, &tunnel_hdr, INT_H_SIZE);
2231 skb_copy_to_linear_data_offset(outbuf, INT_H_SIZE, iter->data,
2232 length);
2233 tipc_link_send_buf(tunnel, outbuf);
2234 if (!tipc_link_is_up(l_ptr))
2235 return;
2236 iter = iter->next;
2237 }
2238 }
2239
2240 /**
2241 * buf_extract - extracts embedded TIPC message from another message
2242 * @skb: encapsulating message buffer
2243 * @from_pos: offset to extract from
2244 *
2245 * Returns a new message buffer containing an embedded message. The
2246 * encapsulating message itself is left unchanged.
2247 */
2248 static struct sk_buff *buf_extract(struct sk_buff *skb, u32 from_pos)
2249 {
2250 struct tipc_msg *msg = (struct tipc_msg *)(skb->data + from_pos);
2251 u32 size = msg_size(msg);
2252 struct sk_buff *eb;
2253
2254 eb = tipc_buf_acquire(size);
2255 if (eb)
2256 skb_copy_to_linear_data(eb, msg, size);
2257 return eb;
2258 }
2259
2260 /*
2261 * link_recv_changeover_msg(): Receive tunneled packet sent
2262 * via other link. Node is locked. Return extracted buffer.
2263 */
2264 static int link_recv_changeover_msg(struct tipc_link **l_ptr,
2265 struct sk_buff **buf)
2266 {
2267 struct sk_buff *tunnel_buf = *buf;
2268 struct tipc_link *dest_link;
2269 struct tipc_msg *msg;
2270 struct tipc_msg *tunnel_msg = buf_msg(tunnel_buf);
2271 u32 msg_typ = msg_type(tunnel_msg);
2272 u32 msg_count = msg_msgcnt(tunnel_msg);
2273 u32 bearer_id = msg_bearer_id(tunnel_msg);
2274
2275 if (bearer_id >= MAX_BEARERS)
2276 goto exit;
2277 dest_link = (*l_ptr)->owner->links[bearer_id];
2278 if (!dest_link)
2279 goto exit;
2280 if (dest_link == *l_ptr) {
2281 pr_err("Unexpected changeover message on link <%s>\n",
2282 (*l_ptr)->name);
2283 goto exit;
2284 }
2285 *l_ptr = dest_link;
2286 msg = msg_get_wrapped(tunnel_msg);
2287
2288 if (msg_typ == DUPLICATE_MSG) {
2289 if (less(msg_seqno(msg), mod(dest_link->next_in_no)))
2290 goto exit;
2291 *buf = buf_extract(tunnel_buf, INT_H_SIZE);
2292 if (*buf == NULL) {
2293 pr_warn("%sduplicate msg dropped\n", link_co_err);
2294 goto exit;
2295 }
2296 kfree_skb(tunnel_buf);
2297 return 1;
2298 }
2299
2300 /* First original message ?: */
2301 if (tipc_link_is_up(dest_link)) {
2302 pr_info("%s<%s>, changeover initiated by peer\n", link_rst_msg,
2303 dest_link->name);
2304 tipc_link_reset(dest_link);
2305 dest_link->exp_msg_count = msg_count;
2306 if (!msg_count)
2307 goto exit;
2308 } else if (dest_link->exp_msg_count == START_CHANGEOVER) {
2309 dest_link->exp_msg_count = msg_count;
2310 if (!msg_count)
2311 goto exit;
2312 }
2313
2314 /* Receive original message */
2315 if (dest_link->exp_msg_count == 0) {
2316 pr_warn("%sgot too many tunnelled messages\n", link_co_err);
2317 goto exit;
2318 }
2319 dest_link->exp_msg_count--;
2320 if (less(msg_seqno(msg), dest_link->reset_checkpoint)) {
2321 goto exit;
2322 } else {
2323 *buf = buf_extract(tunnel_buf, INT_H_SIZE);
2324 if (*buf != NULL) {
2325 kfree_skb(tunnel_buf);
2326 return 1;
2327 } else {
2328 pr_warn("%soriginal msg dropped\n", link_co_err);
2329 }
2330 }
2331 exit:
2332 *buf = NULL;
2333 kfree_skb(tunnel_buf);
2334 return 0;
2335 }
2336
2337 /*
2338 * Bundler functionality:
2339 */
2340 void tipc_link_recv_bundle(struct sk_buff *buf)
2341 {
2342 u32 msgcount = msg_msgcnt(buf_msg(buf));
2343 u32 pos = INT_H_SIZE;
2344 struct sk_buff *obuf;
2345
2346 while (msgcount--) {
2347 obuf = buf_extract(buf, pos);
2348 if (obuf == NULL) {
2349 pr_warn("Link unable to unbundle message(s)\n");
2350 break;
2351 }
2352 pos += align(msg_size(buf_msg(obuf)));
2353 tipc_net_route_msg(obuf);
2354 }
2355 kfree_skb(buf);
2356 }
2357
2358 /*
2359 * Fragmentation/defragmentation:
2360 */
2361
2362 /*
2363 * link_send_long_buf: Entry for buffers needing fragmentation.
2364 * The buffer is complete, inclusive total message length.
2365 * Returns user data length.
2366 */
2367 static int link_send_long_buf(struct tipc_link *l_ptr, struct sk_buff *buf)
2368 {
2369 struct sk_buff *buf_chain = NULL;
2370 struct sk_buff *buf_chain_tail = (struct sk_buff *)&buf_chain;
2371 struct tipc_msg *inmsg = buf_msg(buf);
2372 struct tipc_msg fragm_hdr;
2373 u32 insize = msg_size(inmsg);
2374 u32 dsz = msg_data_sz(inmsg);
2375 unchar *crs = buf->data;
2376 u32 rest = insize;
2377 u32 pack_sz = l_ptr->max_pkt;
2378 u32 fragm_sz = pack_sz - INT_H_SIZE;
2379 u32 fragm_no = 0;
2380 u32 destaddr;
2381
2382 if (msg_short(inmsg))
2383 destaddr = l_ptr->addr;
2384 else
2385 destaddr = msg_destnode(inmsg);
2386
2387 /* Prepare reusable fragment header: */
2388 tipc_msg_init(&fragm_hdr, MSG_FRAGMENTER, FIRST_FRAGMENT,
2389 INT_H_SIZE, destaddr);
2390
2391 /* Chop up message: */
2392 while (rest > 0) {
2393 struct sk_buff *fragm;
2394
2395 if (rest <= fragm_sz) {
2396 fragm_sz = rest;
2397 msg_set_type(&fragm_hdr, LAST_FRAGMENT);
2398 }
2399 fragm = tipc_buf_acquire(fragm_sz + INT_H_SIZE);
2400 if (fragm == NULL) {
2401 kfree_skb(buf);
2402 while (buf_chain) {
2403 buf = buf_chain;
2404 buf_chain = buf_chain->next;
2405 kfree_skb(buf);
2406 }
2407 return -ENOMEM;
2408 }
2409 msg_set_size(&fragm_hdr, fragm_sz + INT_H_SIZE);
2410 fragm_no++;
2411 msg_set_fragm_no(&fragm_hdr, fragm_no);
2412 skb_copy_to_linear_data(fragm, &fragm_hdr, INT_H_SIZE);
2413 skb_copy_to_linear_data_offset(fragm, INT_H_SIZE, crs,
2414 fragm_sz);
2415 buf_chain_tail->next = fragm;
2416 buf_chain_tail = fragm;
2417
2418 rest -= fragm_sz;
2419 crs += fragm_sz;
2420 msg_set_type(&fragm_hdr, FRAGMENT);
2421 }
2422 kfree_skb(buf);
2423
2424 /* Append chain of fragments to send queue & send them */
2425 l_ptr->long_msg_seq_no++;
2426 link_add_chain_to_outqueue(l_ptr, buf_chain, l_ptr->long_msg_seq_no);
2427 l_ptr->stats.sent_fragments += fragm_no;
2428 l_ptr->stats.sent_fragmented++;
2429 tipc_link_push_queue(l_ptr);
2430
2431 return dsz;
2432 }
2433
2434 /*
2435 * A pending message being re-assembled must store certain values
2436 * to handle subsequent fragments correctly. The following functions
2437 * help storing these values in unused, available fields in the
2438 * pending message. This makes dynamic memory allocation unnecessary.
2439 */
2440 static void set_long_msg_seqno(struct sk_buff *buf, u32 seqno)
2441 {
2442 msg_set_seqno(buf_msg(buf), seqno);
2443 }
2444
2445 static u32 get_fragm_size(struct sk_buff *buf)
2446 {
2447 return msg_ack(buf_msg(buf));
2448 }
2449
2450 static void set_fragm_size(struct sk_buff *buf, u32 sz)
2451 {
2452 msg_set_ack(buf_msg(buf), sz);
2453 }
2454
2455 static u32 get_expected_frags(struct sk_buff *buf)
2456 {
2457 return msg_bcast_ack(buf_msg(buf));
2458 }
2459
2460 static void set_expected_frags(struct sk_buff *buf, u32 exp)
2461 {
2462 msg_set_bcast_ack(buf_msg(buf), exp);
2463 }
2464
2465 /*
2466 * tipc_link_recv_fragment(): Called with node lock on. Returns
2467 * the reassembled buffer if message is complete.
2468 */
2469 int tipc_link_recv_fragment(struct sk_buff **pending, struct sk_buff **fb,
2470 struct tipc_msg **m)
2471 {
2472 struct sk_buff *prev = NULL;
2473 struct sk_buff *fbuf = *fb;
2474 struct tipc_msg *fragm = buf_msg(fbuf);
2475 struct sk_buff *pbuf = *pending;
2476 u32 long_msg_seq_no = msg_long_msgno(fragm);
2477
2478 *fb = NULL;
2479
2480 /* Is there an incomplete message waiting for this fragment? */
2481 while (pbuf && ((buf_seqno(pbuf) != long_msg_seq_no) ||
2482 (msg_orignode(fragm) != msg_orignode(buf_msg(pbuf))))) {
2483 prev = pbuf;
2484 pbuf = pbuf->next;
2485 }
2486
2487 if (!pbuf && (msg_type(fragm) == FIRST_FRAGMENT)) {
2488 struct tipc_msg *imsg = (struct tipc_msg *)msg_data(fragm);
2489 u32 msg_sz = msg_size(imsg);
2490 u32 fragm_sz = msg_data_sz(fragm);
2491 u32 exp_fragm_cnt;
2492 u32 max = TIPC_MAX_USER_MSG_SIZE + NAMED_H_SIZE;
2493
2494 if (msg_type(imsg) == TIPC_MCAST_MSG)
2495 max = TIPC_MAX_USER_MSG_SIZE + MCAST_H_SIZE;
2496 if (fragm_sz == 0 || msg_size(imsg) > max) {
2497 kfree_skb(fbuf);
2498 return 0;
2499 }
2500 exp_fragm_cnt = msg_sz / fragm_sz + !!(msg_sz % fragm_sz);
2501 pbuf = tipc_buf_acquire(msg_size(imsg));
2502 if (pbuf != NULL) {
2503 pbuf->next = *pending;
2504 *pending = pbuf;
2505 skb_copy_to_linear_data(pbuf, imsg,
2506 msg_data_sz(fragm));
2507 /* Prepare buffer for subsequent fragments. */
2508 set_long_msg_seqno(pbuf, long_msg_seq_no);
2509 set_fragm_size(pbuf, fragm_sz);
2510 set_expected_frags(pbuf, exp_fragm_cnt - 1);
2511 } else {
2512 pr_debug("Link unable to reassemble fragmented message\n");
2513 kfree_skb(fbuf);
2514 return -1;
2515 }
2516 kfree_skb(fbuf);
2517 return 0;
2518 } else if (pbuf && (msg_type(fragm) != FIRST_FRAGMENT)) {
2519 u32 dsz = msg_data_sz(fragm);
2520 u32 fsz = get_fragm_size(pbuf);
2521 u32 crs = ((msg_fragm_no(fragm) - 1) * fsz);
2522 u32 exp_frags = get_expected_frags(pbuf) - 1;
2523 skb_copy_to_linear_data_offset(pbuf, crs,
2524 msg_data(fragm), dsz);
2525 kfree_skb(fbuf);
2526
2527 /* Is message complete? */
2528 if (exp_frags == 0) {
2529 if (prev)
2530 prev->next = pbuf->next;
2531 else
2532 *pending = pbuf->next;
2533 msg_reset_reroute_cnt(buf_msg(pbuf));
2534 *fb = pbuf;
2535 *m = buf_msg(pbuf);
2536 return 1;
2537 }
2538 set_expected_frags(pbuf, exp_frags);
2539 return 0;
2540 }
2541 kfree_skb(fbuf);
2542 return 0;
2543 }
2544
2545 static void link_set_supervision_props(struct tipc_link *l_ptr, u32 tolerance)
2546 {
2547 if ((tolerance < TIPC_MIN_LINK_TOL) || (tolerance > TIPC_MAX_LINK_TOL))
2548 return;
2549
2550 l_ptr->tolerance = tolerance;
2551 l_ptr->continuity_interval =
2552 ((tolerance / 4) > 500) ? 500 : tolerance / 4;
2553 l_ptr->abort_limit = tolerance / (l_ptr->continuity_interval / 4);
2554 }
2555
2556 void tipc_link_set_queue_limits(struct tipc_link *l_ptr, u32 window)
2557 {
2558 /* Data messages from this node, inclusive FIRST_FRAGM */
2559 l_ptr->queue_limit[TIPC_LOW_IMPORTANCE] = window;
2560 l_ptr->queue_limit[TIPC_MEDIUM_IMPORTANCE] = (window / 3) * 4;
2561 l_ptr->queue_limit[TIPC_HIGH_IMPORTANCE] = (window / 3) * 5;
2562 l_ptr->queue_limit[TIPC_CRITICAL_IMPORTANCE] = (window / 3) * 6;
2563 /* Transiting data messages,inclusive FIRST_FRAGM */
2564 l_ptr->queue_limit[TIPC_LOW_IMPORTANCE + 4] = 300;
2565 l_ptr->queue_limit[TIPC_MEDIUM_IMPORTANCE + 4] = 600;
2566 l_ptr->queue_limit[TIPC_HIGH_IMPORTANCE + 4] = 900;
2567 l_ptr->queue_limit[TIPC_CRITICAL_IMPORTANCE + 4] = 1200;
2568 l_ptr->queue_limit[CONN_MANAGER] = 1200;
2569 l_ptr->queue_limit[CHANGEOVER_PROTOCOL] = 2500;
2570 l_ptr->queue_limit[NAME_DISTRIBUTOR] = 3000;
2571 /* FRAGMENT and LAST_FRAGMENT packets */
2572 l_ptr->queue_limit[MSG_FRAGMENTER] = 4000;
2573 }
2574
2575 /**
2576 * link_find_link - locate link by name
2577 * @name: ptr to link name string
2578 * @node: ptr to area to be filled with ptr to associated node
2579 *
2580 * Caller must hold 'tipc_net_lock' to ensure node and bearer are not deleted;
2581 * this also prevents link deletion.
2582 *
2583 * Returns pointer to link (or 0 if invalid link name).
2584 */
2585 static struct tipc_link *link_find_link(const char *name,
2586 struct tipc_node **node)
2587 {
2588 struct tipc_link_name link_name_parts;
2589 struct tipc_bearer *b_ptr;
2590 struct tipc_link *l_ptr;
2591
2592 if (!link_name_validate(name, &link_name_parts))
2593 return NULL;
2594
2595 b_ptr = tipc_bearer_find_interface(link_name_parts.if_local);
2596 if (!b_ptr)
2597 return NULL;
2598
2599 *node = tipc_node_find(link_name_parts.addr_peer);
2600 if (!*node)
2601 return NULL;
2602
2603 l_ptr = (*node)->links[b_ptr->identity];
2604 if (!l_ptr || strcmp(l_ptr->name, name))
2605 return NULL;
2606
2607 return l_ptr;
2608 }
2609
2610 /**
2611 * link_value_is_valid -- validate proposed link tolerance/priority/window
2612 *
2613 * @cmd: value type (TIPC_CMD_SET_LINK_*)
2614 * @new_value: the new value
2615 *
2616 * Returns 1 if value is within range, 0 if not.
2617 */
2618 static int link_value_is_valid(u16 cmd, u32 new_value)
2619 {
2620 switch (cmd) {
2621 case TIPC_CMD_SET_LINK_TOL:
2622 return (new_value >= TIPC_MIN_LINK_TOL) &&
2623 (new_value <= TIPC_MAX_LINK_TOL);
2624 case TIPC_CMD_SET_LINK_PRI:
2625 return (new_value <= TIPC_MAX_LINK_PRI);
2626 case TIPC_CMD_SET_LINK_WINDOW:
2627 return (new_value >= TIPC_MIN_LINK_WIN) &&
2628 (new_value <= TIPC_MAX_LINK_WIN);
2629 }
2630 return 0;
2631 }
2632
2633 /**
2634 * link_cmd_set_value - change priority/tolerance/window for link/bearer/media
2635 * @name: ptr to link, bearer, or media name
2636 * @new_value: new value of link, bearer, or media setting
2637 * @cmd: which link, bearer, or media attribute to set (TIPC_CMD_SET_LINK_*)
2638 *
2639 * Caller must hold 'tipc_net_lock' to ensure link/bearer/media is not deleted.
2640 *
2641 * Returns 0 if value updated and negative value on error.
2642 */
2643 static int link_cmd_set_value(const char *name, u32 new_value, u16 cmd)
2644 {
2645 struct tipc_node *node;
2646 struct tipc_link *l_ptr;
2647 struct tipc_bearer *b_ptr;
2648 struct tipc_media *m_ptr;
2649
2650 l_ptr = link_find_link(name, &node);
2651 if (l_ptr) {
2652 /*
2653 * acquire node lock for tipc_link_send_proto_msg().
2654 * see "TIPC locking policy" in net.c.
2655 */
2656 tipc_node_lock(node);
2657 switch (cmd) {
2658 case TIPC_CMD_SET_LINK_TOL:
2659 link_set_supervision_props(l_ptr, new_value);
2660 tipc_link_send_proto_msg(l_ptr,
2661 STATE_MSG, 0, 0, new_value, 0, 0);
2662 break;
2663 case TIPC_CMD_SET_LINK_PRI:
2664 l_ptr->priority = new_value;
2665 tipc_link_send_proto_msg(l_ptr,
2666 STATE_MSG, 0, 0, 0, new_value, 0);
2667 break;
2668 case TIPC_CMD_SET_LINK_WINDOW:
2669 tipc_link_set_queue_limits(l_ptr, new_value);
2670 break;
2671 }
2672 tipc_node_unlock(node);
2673 return 0;
2674 }
2675
2676 b_ptr = tipc_bearer_find(name);
2677 if (b_ptr) {
2678 switch (cmd) {
2679 case TIPC_CMD_SET_LINK_TOL:
2680 b_ptr->tolerance = new_value;
2681 return 0;
2682 case TIPC_CMD_SET_LINK_PRI:
2683 b_ptr->priority = new_value;
2684 return 0;
2685 case TIPC_CMD_SET_LINK_WINDOW:
2686 b_ptr->window = new_value;
2687 return 0;
2688 }
2689 return -EINVAL;
2690 }
2691
2692 m_ptr = tipc_media_find(name);
2693 if (!m_ptr)
2694 return -ENODEV;
2695 switch (cmd) {
2696 case TIPC_CMD_SET_LINK_TOL:
2697 m_ptr->tolerance = new_value;
2698 return 0;
2699 case TIPC_CMD_SET_LINK_PRI:
2700 m_ptr->priority = new_value;
2701 return 0;
2702 case TIPC_CMD_SET_LINK_WINDOW:
2703 m_ptr->window = new_value;
2704 return 0;
2705 }
2706 return -EINVAL;
2707 }
2708
2709 struct sk_buff *tipc_link_cmd_config(const void *req_tlv_area, int req_tlv_space,
2710 u16 cmd)
2711 {
2712 struct tipc_link_config *args;
2713 u32 new_value;
2714 int res;
2715
2716 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_CONFIG))
2717 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
2718
2719 args = (struct tipc_link_config *)TLV_DATA(req_tlv_area);
2720 new_value = ntohl(args->value);
2721
2722 if (!link_value_is_valid(cmd, new_value))
2723 return tipc_cfg_reply_error_string(
2724 "cannot change, value invalid");
2725
2726 if (!strcmp(args->name, tipc_bclink_name)) {
2727 if ((cmd == TIPC_CMD_SET_LINK_WINDOW) &&
2728 (tipc_bclink_set_queue_limits(new_value) == 0))
2729 return tipc_cfg_reply_none();
2730 return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED
2731 " (cannot change setting on broadcast link)");
2732 }
2733
2734 read_lock_bh(&tipc_net_lock);
2735 res = link_cmd_set_value(args->name, new_value, cmd);
2736 read_unlock_bh(&tipc_net_lock);
2737 if (res)
2738 return tipc_cfg_reply_error_string("cannot change link setting");
2739
2740 return tipc_cfg_reply_none();
2741 }
2742
2743 /**
2744 * link_reset_statistics - reset link statistics
2745 * @l_ptr: pointer to link
2746 */
2747 static void link_reset_statistics(struct tipc_link *l_ptr)
2748 {
2749 memset(&l_ptr->stats, 0, sizeof(l_ptr->stats));
2750 l_ptr->stats.sent_info = l_ptr->next_out_no;
2751 l_ptr->stats.recv_info = l_ptr->next_in_no;
2752 }
2753
2754 struct sk_buff *tipc_link_cmd_reset_stats(const void *req_tlv_area, int req_tlv_space)
2755 {
2756 char *link_name;
2757 struct tipc_link *l_ptr;
2758 struct tipc_node *node;
2759
2760 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_NAME))
2761 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
2762
2763 link_name = (char *)TLV_DATA(req_tlv_area);
2764 if (!strcmp(link_name, tipc_bclink_name)) {
2765 if (tipc_bclink_reset_stats())
2766 return tipc_cfg_reply_error_string("link not found");
2767 return tipc_cfg_reply_none();
2768 }
2769
2770 read_lock_bh(&tipc_net_lock);
2771 l_ptr = link_find_link(link_name, &node);
2772 if (!l_ptr) {
2773 read_unlock_bh(&tipc_net_lock);
2774 return tipc_cfg_reply_error_string("link not found");
2775 }
2776
2777 tipc_node_lock(node);
2778 link_reset_statistics(l_ptr);
2779 tipc_node_unlock(node);
2780 read_unlock_bh(&tipc_net_lock);
2781 return tipc_cfg_reply_none();
2782 }
2783
2784 /**
2785 * percent - convert count to a percentage of total (rounding up or down)
2786 */
2787 static u32 percent(u32 count, u32 total)
2788 {
2789 return (count * 100 + (total / 2)) / total;
2790 }
2791
2792 /**
2793 * tipc_link_stats - print link statistics
2794 * @name: link name
2795 * @buf: print buffer area
2796 * @buf_size: size of print buffer area
2797 *
2798 * Returns length of print buffer data string (or 0 if error)
2799 */
2800 static int tipc_link_stats(const char *name, char *buf, const u32 buf_size)
2801 {
2802 struct tipc_link *l;
2803 struct tipc_stats *s;
2804 struct tipc_node *node;
2805 char *status;
2806 u32 profile_total = 0;
2807 int ret;
2808
2809 if (!strcmp(name, tipc_bclink_name))
2810 return tipc_bclink_stats(buf, buf_size);
2811
2812 read_lock_bh(&tipc_net_lock);
2813 l = link_find_link(name, &node);
2814 if (!l) {
2815 read_unlock_bh(&tipc_net_lock);
2816 return 0;
2817 }
2818 tipc_node_lock(node);
2819 s = &l->stats;
2820
2821 if (tipc_link_is_active(l))
2822 status = "ACTIVE";
2823 else if (tipc_link_is_up(l))
2824 status = "STANDBY";
2825 else
2826 status = "DEFUNCT";
2827
2828 ret = tipc_snprintf(buf, buf_size, "Link <%s>\n"
2829 " %s MTU:%u Priority:%u Tolerance:%u ms"
2830 " Window:%u packets\n",
2831 l->name, status, l->max_pkt, l->priority,
2832 l->tolerance, l->queue_limit[0]);
2833
2834 ret += tipc_snprintf(buf + ret, buf_size - ret,
2835 " RX packets:%u fragments:%u/%u bundles:%u/%u\n",
2836 l->next_in_no - s->recv_info, s->recv_fragments,
2837 s->recv_fragmented, s->recv_bundles,
2838 s->recv_bundled);
2839
2840 ret += tipc_snprintf(buf + ret, buf_size - ret,
2841 " TX packets:%u fragments:%u/%u bundles:%u/%u\n",
2842 l->next_out_no - s->sent_info, s->sent_fragments,
2843 s->sent_fragmented, s->sent_bundles,
2844 s->sent_bundled);
2845
2846 profile_total = s->msg_length_counts;
2847 if (!profile_total)
2848 profile_total = 1;
2849
2850 ret += tipc_snprintf(buf + ret, buf_size - ret,
2851 " TX profile sample:%u packets average:%u octets\n"
2852 " 0-64:%u%% -256:%u%% -1024:%u%% -4096:%u%% "
2853 "-16384:%u%% -32768:%u%% -66000:%u%%\n",
2854 s->msg_length_counts,
2855 s->msg_lengths_total / profile_total,
2856 percent(s->msg_length_profile[0], profile_total),
2857 percent(s->msg_length_profile[1], profile_total),
2858 percent(s->msg_length_profile[2], profile_total),
2859 percent(s->msg_length_profile[3], profile_total),
2860 percent(s->msg_length_profile[4], profile_total),
2861 percent(s->msg_length_profile[5], profile_total),
2862 percent(s->msg_length_profile[6], profile_total));
2863
2864 ret += tipc_snprintf(buf + ret, buf_size - ret,
2865 " RX states:%u probes:%u naks:%u defs:%u"
2866 " dups:%u\n", s->recv_states, s->recv_probes,
2867 s->recv_nacks, s->deferred_recv, s->duplicates);
2868
2869 ret += tipc_snprintf(buf + ret, buf_size - ret,
2870 " TX states:%u probes:%u naks:%u acks:%u"
2871 " dups:%u\n", s->sent_states, s->sent_probes,
2872 s->sent_nacks, s->sent_acks, s->retransmitted);
2873
2874 ret += tipc_snprintf(buf + ret, buf_size - ret,
2875 " Congestion link:%u Send queue"
2876 " max:%u avg:%u\n", s->link_congs,
2877 s->max_queue_sz, s->queue_sz_counts ?
2878 (s->accu_queue_sz / s->queue_sz_counts) : 0);
2879
2880 tipc_node_unlock(node);
2881 read_unlock_bh(&tipc_net_lock);
2882 return ret;
2883 }
2884
2885 struct sk_buff *tipc_link_cmd_show_stats(const void *req_tlv_area, int req_tlv_space)
2886 {
2887 struct sk_buff *buf;
2888 struct tlv_desc *rep_tlv;
2889 int str_len;
2890 int pb_len;
2891 char *pb;
2892
2893 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_LINK_NAME))
2894 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
2895
2896 buf = tipc_cfg_reply_alloc(TLV_SPACE(ULTRA_STRING_MAX_LEN));
2897 if (!buf)
2898 return NULL;
2899
2900 rep_tlv = (struct tlv_desc *)buf->data;
2901 pb = TLV_DATA(rep_tlv);
2902 pb_len = ULTRA_STRING_MAX_LEN;
2903 str_len = tipc_link_stats((char *)TLV_DATA(req_tlv_area),
2904 pb, pb_len);
2905 if (!str_len) {
2906 kfree_skb(buf);
2907 return tipc_cfg_reply_error_string("link not found");
2908 }
2909 str_len += 1; /* for "\0" */
2910 skb_put(buf, TLV_SPACE(str_len));
2911 TLV_SET(rep_tlv, TIPC_TLV_ULTRA_STRING, NULL, str_len);
2912
2913 return buf;
2914 }
2915
2916 /**
2917 * tipc_link_get_max_pkt - get maximum packet size to use when sending to destination
2918 * @dest: network address of destination node
2919 * @selector: used to select from set of active links
2920 *
2921 * If no active link can be found, uses default maximum packet size.
2922 */
2923 u32 tipc_link_get_max_pkt(u32 dest, u32 selector)
2924 {
2925 struct tipc_node *n_ptr;
2926 struct tipc_link *l_ptr;
2927 u32 res = MAX_PKT_DEFAULT;
2928
2929 if (dest == tipc_own_addr)
2930 return MAX_MSG_SIZE;
2931
2932 read_lock_bh(&tipc_net_lock);
2933 n_ptr = tipc_node_find(dest);
2934 if (n_ptr) {
2935 tipc_node_lock(n_ptr);
2936 l_ptr = n_ptr->active_links[selector & 1];
2937 if (l_ptr)
2938 res = l_ptr->max_pkt;
2939 tipc_node_unlock(n_ptr);
2940 }
2941 read_unlock_bh(&tipc_net_lock);
2942 return res;
2943 }
2944
2945 static void link_print(struct tipc_link *l_ptr, const char *str)
2946 {
2947 pr_info("%s Link %x<%s>:", str, l_ptr->addr, l_ptr->b_ptr->name);
2948
2949 if (link_working_unknown(l_ptr))
2950 pr_cont(":WU\n");
2951 else if (link_reset_reset(l_ptr))
2952 pr_cont(":RR\n");
2953 else if (link_reset_unknown(l_ptr))
2954 pr_cont(":RU\n");
2955 else if (link_working_working(l_ptr))
2956 pr_cont(":WW\n");
2957 else
2958 pr_cont("\n");
2959 }
Linus' kernel tree