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authorPer Liden <per.liden@nospam.ericsson.com>2006-01-02 13:04:38 -0500
committerDavid S. Miller <davem@sunset.davemloft.net>2006-01-12 17:06:31 -0500
commitb97bf3fd8f6a16966d4f18983b2c40993ff937d4 (patch)
tree59959f8a0f3087455efdcb430846686f303c5991 /net/tipc/bearer.c
parent58cba4650a7a414eabd2b40cc9d8e45fcdf192d9 (diff)
[TIPC] Initial merge
TIPC (Transparent Inter Process Communication) is a protocol designed for intra cluster communication. For more information see http://tipc.sourceforge.net Signed-off-by: Per Liden <per.liden@nospam.ericsson.com>
Diffstat (limited to 'net/tipc/bearer.c')
-rw-r--r--net/tipc/bearer.c689
1 files changed, 689 insertions, 0 deletions
diff --git a/net/tipc/bearer.c b/net/tipc/bearer.c
new file mode 100644
index 000000000000..c19465c5f035
--- /dev/null
+++ b/net/tipc/bearer.c
@@ -0,0 +1,689 @@
1/*
2 * net/tipc/bearer.c: TIPC bearer code
3 *
4 * Copyright (c) 2003-2005, Ericsson Research Canada
5 * Copyright (c) 2004-2005, Wind River Systems
6 * Copyright (c) 2005-2006, Ericsson AB
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions are met:
11 *
12 * Redistributions of source code must retain the above copyright notice, this
13 * list of conditions and the following disclaimer.
14 * Redistributions in binary form must reproduce the above copyright notice,
15 * this list of conditions and the following disclaimer in the documentation
16 * and/or other materials provided with the distribution.
17 * Neither the names of the copyright holders nor the names of its
18 * contributors may be used to endorse or promote products derived from this
19 * software without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
22 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
25 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31 * POSSIBILITY OF SUCH DAMAGE.
32 */
33
34#include "core.h"
35#include "config.h"
36#include "dbg.h"
37#include "bearer.h"
38#include "link.h"
39#include "port.h"
40#include "discover.h"
41#include "bcast.h"
42
43#define MAX_ADDR_STR 32
44
45static struct media *media_list = 0;
46static u32 media_count = 0;
47
48struct bearer *bearers = 0;
49
50/**
51 * media_name_valid - validate media name
52 *
53 * Returns 1 if media name is valid, otherwise 0.
54 */
55
56static int media_name_valid(const char *name)
57{
58 u32 len;
59
60 len = strlen(name);
61 if ((len + 1) > TIPC_MAX_MEDIA_NAME)
62 return 0;
63 return (strspn(name, tipc_alphabet) == len);
64}
65
66/**
67 * media_find - locates specified media object by name
68 */
69
70static struct media *media_find(const char *name)
71{
72 struct media *m_ptr;
73 u32 i;
74
75 for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
76 if (!strcmp(m_ptr->name, name))
77 return m_ptr;
78 }
79 return 0;
80}
81
82/**
83 * tipc_register_media - register a media type
84 *
85 * Bearers for this media type must be activated separately at a later stage.
86 */
87
88int tipc_register_media(u32 media_type,
89 char *name,
90 int (*enable)(struct tipc_bearer *),
91 void (*disable)(struct tipc_bearer *),
92 int (*send_msg)(struct sk_buff *,
93 struct tipc_bearer *,
94 struct tipc_media_addr *),
95 char *(*addr2str)(struct tipc_media_addr *a,
96 char *str_buf, int str_size),
97 struct tipc_media_addr *bcast_addr,
98 const u32 bearer_priority,
99 const u32 link_tolerance, /* [ms] */
100 const u32 send_window_limit)
101{
102 struct media *m_ptr;
103 u32 media_id;
104 u32 i;
105 int res = -EINVAL;
106
107 write_lock_bh(&net_lock);
108 if (!media_list)
109 goto exit;
110
111 if (!media_name_valid(name)) {
112 warn("Media registration error: illegal name <%s>\n", name);
113 goto exit;
114 }
115 if (!bcast_addr) {
116 warn("Media registration error: no broadcast address supplied\n");
117 goto exit;
118 }
119 if (bearer_priority >= TIPC_NUM_LINK_PRI) {
120 warn("Media registration error: priority %u\n", bearer_priority);
121 goto exit;
122 }
123 if ((link_tolerance < TIPC_MIN_LINK_TOL) ||
124 (link_tolerance > TIPC_MAX_LINK_TOL)) {
125 warn("Media registration error: tolerance %u\n", link_tolerance);
126 goto exit;
127 }
128
129 media_id = media_count++;
130 if (media_id >= MAX_MEDIA) {
131 warn("Attempt to register more than %u media\n", MAX_MEDIA);
132 media_count--;
133 goto exit;
134 }
135 for (i = 0; i < media_id; i++) {
136 if (media_list[i].type_id == media_type) {
137 warn("Attempt to register second media with type %u\n",
138 media_type);
139 media_count--;
140 goto exit;
141 }
142 if (!strcmp(name, media_list[i].name)) {
143 warn("Attempt to re-register media name <%s>\n", name);
144 media_count--;
145 goto exit;
146 }
147 }
148
149 m_ptr = &media_list[media_id];
150 m_ptr->type_id = media_type;
151 m_ptr->send_msg = send_msg;
152 m_ptr->enable_bearer = enable;
153 m_ptr->disable_bearer = disable;
154 m_ptr->addr2str = addr2str;
155 memcpy(&m_ptr->bcast_addr, bcast_addr, sizeof(*bcast_addr));
156 m_ptr->bcast = 1;
157 strcpy(m_ptr->name, name);
158 m_ptr->priority = bearer_priority;
159 m_ptr->tolerance = link_tolerance;
160 m_ptr->window = send_window_limit;
161 dbg("Media <%s> registered\n", name);
162 res = 0;
163exit:
164 write_unlock_bh(&net_lock);
165 return res;
166}
167
168/**
169 * media_addr_printf - record media address in print buffer
170 */
171
172void media_addr_printf(struct print_buf *pb, struct tipc_media_addr *a)
173{
174 struct media *m_ptr;
175 u32 media_type;
176 u32 i;
177
178 media_type = ntohl(a->type);
179 for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
180 if (m_ptr->type_id == media_type)
181 break;
182 }
183
184 if ((i < media_count) && (m_ptr->addr2str != NULL)) {
185 char addr_str[MAX_ADDR_STR];
186
187 tipc_printf(pb, "%s(%s) ", m_ptr->name,
188 m_ptr->addr2str(a, addr_str, sizeof(addr_str)));
189 } else {
190 unchar *addr = (unchar *)&a->dev_addr;
191
192 tipc_printf(pb, "UNKNOWN(%u):", media_type);
193 for (i = 0; i < (sizeof(*a) - sizeof(a->type)); i++) {
194 tipc_printf(pb, "%02x ", addr[i]);
195 }
196 }
197}
198
199/**
200 * media_get_names - record names of registered media in buffer
201 */
202
203struct sk_buff *media_get_names(void)
204{
205 struct sk_buff *buf;
206 struct media *m_ptr;
207 int i;
208
209 buf = cfg_reply_alloc(MAX_MEDIA * TLV_SPACE(TIPC_MAX_MEDIA_NAME));
210 if (!buf)
211 return NULL;
212
213 read_lock_bh(&net_lock);
214 for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
215 cfg_append_tlv(buf, TIPC_TLV_MEDIA_NAME, m_ptr->name,
216 strlen(m_ptr->name) + 1);
217 }
218 read_unlock_bh(&net_lock);
219 return buf;
220}
221
222/**
223 * bearer_name_validate - validate & (optionally) deconstruct bearer name
224 * @name - ptr to bearer name string
225 * @name_parts - ptr to area for bearer name components (or NULL if not needed)
226 *
227 * Returns 1 if bearer name is valid, otherwise 0.
228 */
229
230static int bearer_name_validate(const char *name,
231 struct bearer_name *name_parts)
232{
233 char name_copy[TIPC_MAX_BEARER_NAME];
234 char *media_name;
235 char *if_name;
236 u32 media_len;
237 u32 if_len;
238
239 /* copy bearer name & ensure length is OK */
240
241 name_copy[TIPC_MAX_BEARER_NAME - 1] = 0;
242 /* need above in case non-Posix strncpy() doesn't pad with nulls */
243 strncpy(name_copy, name, TIPC_MAX_BEARER_NAME);
244 if (name_copy[TIPC_MAX_BEARER_NAME - 1] != 0)
245 return 0;
246
247 /* ensure all component parts of bearer name are present */
248
249 media_name = name_copy;
250 if ((if_name = strchr(media_name, ':')) == NULL)
251 return 0;
252 *(if_name++) = 0;
253 media_len = if_name - media_name;
254 if_len = strlen(if_name) + 1;
255
256 /* validate component parts of bearer name */
257
258 if ((media_len <= 1) || (media_len > TIPC_MAX_MEDIA_NAME) ||
259 (if_len <= 1) || (if_len > TIPC_MAX_IF_NAME) ||
260 (strspn(media_name, tipc_alphabet) != (media_len - 1)) ||
261 (strspn(if_name, tipc_alphabet) != (if_len - 1)))
262 return 0;
263
264 /* return bearer name components, if necessary */
265
266 if (name_parts) {
267 strcpy(name_parts->media_name, media_name);
268 strcpy(name_parts->if_name, if_name);
269 }
270 return 1;
271}
272
273/**
274 * bearer_find - locates bearer object with matching bearer name
275 */
276
277static struct bearer *bearer_find(const char *name)
278{
279 struct bearer *b_ptr;
280 u32 i;
281
282 for (i = 0, b_ptr = bearers; i < MAX_BEARERS; i++, b_ptr++) {
283 if (b_ptr->active && (!strcmp(b_ptr->publ.name, name)))
284 return b_ptr;
285 }
286 return 0;
287}
288
289/**
290 * bearer_find - locates bearer object with matching interface name
291 */
292
293struct bearer *bearer_find_interface(const char *if_name)
294{
295 struct bearer *b_ptr;
296 char *b_if_name;
297 u32 i;
298
299 for (i = 0, b_ptr = bearers; i < MAX_BEARERS; i++, b_ptr++) {
300 if (!b_ptr->active)
301 continue;
302 b_if_name = strchr(b_ptr->publ.name, ':') + 1;
303 if (!strcmp(b_if_name, if_name))
304 return b_ptr;
305 }
306 return 0;
307}
308
309/**
310 * bearer_get_names - record names of bearers in buffer
311 */
312
313struct sk_buff *bearer_get_names(void)
314{
315 struct sk_buff *buf;
316 struct media *m_ptr;
317 struct bearer *b_ptr;
318 int i, j;
319
320 buf = cfg_reply_alloc(MAX_BEARERS * TLV_SPACE(TIPC_MAX_BEARER_NAME));
321 if (!buf)
322 return NULL;
323
324 read_lock_bh(&net_lock);
325 for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
326 for (j = 0; j < MAX_BEARERS; j++) {
327 b_ptr = &bearers[j];
328 if (b_ptr->active && (b_ptr->media == m_ptr)) {
329 cfg_append_tlv(buf, TIPC_TLV_BEARER_NAME,
330 b_ptr->publ.name,
331 strlen(b_ptr->publ.name) + 1);
332 }
333 }
334 }
335 read_unlock_bh(&net_lock);
336 return buf;
337}
338
339void bearer_add_dest(struct bearer *b_ptr, u32 dest)
340{
341 nmap_add(&b_ptr->nodes, dest);
342 disc_update_link_req(b_ptr->link_req);
343 bcbearer_sort();
344}
345
346void bearer_remove_dest(struct bearer *b_ptr, u32 dest)
347{
348 nmap_remove(&b_ptr->nodes, dest);
349 disc_update_link_req(b_ptr->link_req);
350 bcbearer_sort();
351}
352
353/*
354 * bearer_push(): Resolve bearer congestion. Force the waiting
355 * links to push out their unsent packets, one packet per link
356 * per iteration, until all packets are gone or congestion reoccurs.
357 * 'net_lock' is read_locked when this function is called
358 * bearer.lock must be taken before calling
359 * Returns binary true(1) ore false(0)
360 */
361static int bearer_push(struct bearer *b_ptr)
362{
363 u32 res = TIPC_OK;
364 struct link *ln, *tln;
365
366 if (b_ptr->publ.blocked)
367 return 0;
368
369 while (!list_empty(&b_ptr->cong_links) && (res != PUSH_FAILED)) {
370 list_for_each_entry_safe(ln, tln, &b_ptr->cong_links, link_list) {
371 res = link_push_packet(ln);
372 if (res == PUSH_FAILED)
373 break;
374 if (res == PUSH_FINISHED)
375 list_move_tail(&ln->link_list, &b_ptr->links);
376 }
377 }
378 return list_empty(&b_ptr->cong_links);
379}
380
381void bearer_lock_push(struct bearer *b_ptr)
382{
383 int res;
384
385 spin_lock_bh(&b_ptr->publ.lock);
386 res = bearer_push(b_ptr);
387 spin_unlock_bh(&b_ptr->publ.lock);
388 if (res)
389 bcbearer_push();
390}
391
392
393/*
394 * Interrupt enabling new requests after bearer congestion or blocking:
395 * See bearer_send().
396 */
397void tipc_continue(struct tipc_bearer *tb_ptr)
398{
399 struct bearer *b_ptr = (struct bearer *)tb_ptr;
400
401 spin_lock_bh(&b_ptr->publ.lock);
402 b_ptr->continue_count++;
403 if (!list_empty(&b_ptr->cong_links))
404 k_signal((Handler)bearer_lock_push, (unsigned long)b_ptr);
405 b_ptr->publ.blocked = 0;
406 spin_unlock_bh(&b_ptr->publ.lock);
407}
408
409/*
410 * Schedule link for sending of messages after the bearer
411 * has been deblocked by 'continue()'. This method is called
412 * when somebody tries to send a message via this link while
413 * the bearer is congested. 'net_lock' is in read_lock here
414 * bearer.lock is busy
415 */
416
417static void bearer_schedule_unlocked(struct bearer *b_ptr, struct link *l_ptr)
418{
419 list_move_tail(&l_ptr->link_list, &b_ptr->cong_links);
420}
421
422/*
423 * Schedule link for sending of messages after the bearer
424 * has been deblocked by 'continue()'. This method is called
425 * when somebody tries to send a message via this link while
426 * the bearer is congested. 'net_lock' is in read_lock here,
427 * bearer.lock is free
428 */
429
430void bearer_schedule(struct bearer *b_ptr, struct link *l_ptr)
431{
432 spin_lock_bh(&b_ptr->publ.lock);
433 bearer_schedule_unlocked(b_ptr, l_ptr);
434 spin_unlock_bh(&b_ptr->publ.lock);
435}
436
437
438/*
439 * bearer_resolve_congestion(): Check if there is bearer congestion,
440 * and if there is, try to resolve it before returning.
441 * 'net_lock' is read_locked when this function is called
442 */
443int bearer_resolve_congestion(struct bearer *b_ptr, struct link *l_ptr)
444{
445 int res = 1;
446
447 if (list_empty(&b_ptr->cong_links))
448 return 1;
449 spin_lock_bh(&b_ptr->publ.lock);
450 if (!bearer_push(b_ptr)) {
451 bearer_schedule_unlocked(b_ptr, l_ptr);
452 res = 0;
453 }
454 spin_unlock_bh(&b_ptr->publ.lock);
455 return res;
456}
457
458
459/**
460 * tipc_enable_bearer - enable bearer with the given name
461 */
462
463int tipc_enable_bearer(const char *name, u32 bcast_scope, u32 priority)
464{
465 struct bearer *b_ptr;
466 struct media *m_ptr;
467 struct bearer_name b_name;
468 char addr_string[16];
469 u32 bearer_id;
470 u32 with_this_prio;
471 u32 i;
472 int res = -EINVAL;
473
474 if (tipc_mode != TIPC_NET_MODE)
475 return -ENOPROTOOPT;
476 if (!bearer_name_validate(name, &b_name) ||
477 !addr_domain_valid(bcast_scope) ||
478 !in_scope(bcast_scope, tipc_own_addr) ||
479 (priority > TIPC_NUM_LINK_PRI))
480 return -EINVAL;
481
482 write_lock_bh(&net_lock);
483 if (!bearers)
484 goto failed;
485
486 m_ptr = media_find(b_name.media_name);
487 if (!m_ptr) {
488 warn("No media <%s>\n", b_name.media_name);
489 goto failed;
490 }
491 if (priority == TIPC_NUM_LINK_PRI)
492 priority = m_ptr->priority;
493
494restart:
495 bearer_id = MAX_BEARERS;
496 with_this_prio = 1;
497 for (i = MAX_BEARERS; i-- != 0; ) {
498 if (!bearers[i].active) {
499 bearer_id = i;
500 continue;
501 }
502 if (!strcmp(name, bearers[i].publ.name)) {
503 warn("Bearer <%s> already enabled\n", name);
504 goto failed;
505 }
506 if ((bearers[i].priority == priority) &&
507 (++with_this_prio > 2)) {
508 if (priority-- == 0) {
509 warn("Third bearer <%s> with priority %u, unable to lower to %u\n",
510 name, priority + 1, priority);
511 goto failed;
512 }
513 warn("Third bearer <%s> with priority %u, lowering to %u\n",
514 name, priority + 1, priority);
515 goto restart;
516 }
517 }
518 if (bearer_id >= MAX_BEARERS) {
519 warn("Attempt to enable more than %d bearers\n", MAX_BEARERS);
520 goto failed;
521 }
522
523 b_ptr = &bearers[bearer_id];
524 memset(b_ptr, 0, sizeof(struct bearer));
525
526 strcpy(b_ptr->publ.name, name);
527 res = m_ptr->enable_bearer(&b_ptr->publ);
528 if (res) {
529 warn("Failed to enable bearer <%s>\n", name);
530 goto failed;
531 }
532
533 b_ptr->identity = bearer_id;
534 b_ptr->media = m_ptr;
535 b_ptr->net_plane = bearer_id + 'A';
536 b_ptr->active = 1;
537 b_ptr->detect_scope = bcast_scope;
538 b_ptr->priority = priority;
539 INIT_LIST_HEAD(&b_ptr->cong_links);
540 INIT_LIST_HEAD(&b_ptr->links);
541 if (m_ptr->bcast) {
542 b_ptr->link_req = disc_init_link_req(b_ptr, &m_ptr->bcast_addr,
543 bcast_scope, 2);
544 }
545 b_ptr->publ.lock = SPIN_LOCK_UNLOCKED;
546 write_unlock_bh(&net_lock);
547 info("Enabled bearer <%s>, discovery domain %s\n",
548 name, addr_string_fill(addr_string, bcast_scope));
549 return 0;
550failed:
551 write_unlock_bh(&net_lock);
552 return res;
553}
554
555/**
556 * tipc_block_bearer(): Block the bearer with the given name,
557 * and reset all its links
558 */
559
560int tipc_block_bearer(const char *name)
561{
562 struct bearer *b_ptr = 0;
563 struct link *l_ptr;
564 struct link *temp_l_ptr;
565
566 if (tipc_mode != TIPC_NET_MODE)
567 return -ENOPROTOOPT;
568
569 read_lock_bh(&net_lock);
570 b_ptr = bearer_find(name);
571 if (!b_ptr) {
572 warn("Attempt to block unknown bearer <%s>\n", name);
573 read_unlock_bh(&net_lock);
574 return -EINVAL;
575 }
576
577 spin_lock_bh(&b_ptr->publ.lock);
578 b_ptr->publ.blocked = 1;
579 list_for_each_entry_safe(l_ptr, temp_l_ptr, &b_ptr->links, link_list) {
580 struct node *n_ptr = l_ptr->owner;
581
582 spin_lock_bh(&n_ptr->lock);
583 link_reset(l_ptr);
584 spin_unlock_bh(&n_ptr->lock);
585 }
586 spin_unlock_bh(&b_ptr->publ.lock);
587 read_unlock_bh(&net_lock);
588 info("Blocked bearer <%s>\n", name);
589 return TIPC_OK;
590}
591
592/**
593 * bearer_disable -
594 *
595 * Note: This routine assumes caller holds net_lock.
596 */
597
598static int bearer_disable(const char *name)
599{
600 struct bearer *b_ptr;
601 struct link *l_ptr;
602 struct link *temp_l_ptr;
603
604 if (tipc_mode != TIPC_NET_MODE)
605 return -ENOPROTOOPT;
606
607 b_ptr = bearer_find(name);
608 if (!b_ptr) {
609 warn("Attempt to disable unknown bearer <%s>\n", name);
610 return -EINVAL;
611 }
612
613 disc_stop_link_req(b_ptr->link_req);
614 spin_lock_bh(&b_ptr->publ.lock);
615 b_ptr->link_req = NULL;
616 b_ptr->publ.blocked = 1;
617 if (b_ptr->media->disable_bearer) {
618 spin_unlock_bh(&b_ptr->publ.lock);
619 write_unlock_bh(&net_lock);
620 b_ptr->media->disable_bearer(&b_ptr->publ);
621 write_lock_bh(&net_lock);
622 spin_lock_bh(&b_ptr->publ.lock);
623 }
624 list_for_each_entry_safe(l_ptr, temp_l_ptr, &b_ptr->links, link_list) {
625 link_delete(l_ptr);
626 }
627 spin_unlock_bh(&b_ptr->publ.lock);
628 info("Disabled bearer <%s>\n", name);
629 memset(b_ptr, 0, sizeof(struct bearer));
630 return TIPC_OK;
631}
632
633int tipc_disable_bearer(const char *name)
634{
635 int res;
636
637 write_lock_bh(&net_lock);
638 res = bearer_disable(name);
639 write_unlock_bh(&net_lock);
640 return res;
641}
642
643
644
645int bearer_init(void)
646{
647 int res;
648
649 write_lock_bh(&net_lock);
650 bearers = kmalloc(MAX_BEARERS * sizeof(struct bearer), GFP_ATOMIC);
651 media_list = kmalloc(MAX_MEDIA * sizeof(struct media), GFP_ATOMIC);
652 if (bearers && media_list) {
653 memset(bearers, 0, MAX_BEARERS * sizeof(struct bearer));
654 memset(media_list, 0, MAX_MEDIA * sizeof(struct media));
655 res = TIPC_OK;
656 } else {
657 kfree(bearers);
658 kfree(media_list);
659 bearers = 0;
660 media_list = 0;
661 res = -ENOMEM;
662 }
663 write_unlock_bh(&net_lock);
664 return res;
665}
666
667void bearer_stop(void)
668{
669 u32 i;
670
671 if (!bearers)
672 return;
673
674 for (i = 0; i < MAX_BEARERS; i++) {
675 if (bearers[i].active)
676 bearers[i].publ.blocked = 1;
677 }
678 for (i = 0; i < MAX_BEARERS; i++) {
679 if (bearers[i].active)
680 bearer_disable(bearers[i].publ.name);
681 }
682 kfree(bearers);
683 kfree(media_list);
684 bearers = 0;
685 media_list = 0;
686 media_count = 0;
687}
688
689