[AFS]: Add security support.
[linux-2.6.git] / fs / afs / vlocation.c
1 /* AFS volume location management
2  *
3  * Copyright (C) 2002, 2007 Red Hat, Inc. All Rights Reserved.
4  * Written by David Howells (dhowells@redhat.com)
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * as published by the Free Software Foundation; either version
9  * 2 of the License, or (at your option) any later version.
10  */
11
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include "internal.h"
16
17 unsigned afs_vlocation_timeout = 10;    /* volume location timeout in seconds */
18 unsigned afs_vlocation_update_timeout = 10 * 60;
19
20 static void afs_vlocation_reaper(struct work_struct *);
21 static void afs_vlocation_updater(struct work_struct *);
22
23 static LIST_HEAD(afs_vlocation_updates);
24 static LIST_HEAD(afs_vlocation_graveyard);
25 static DEFINE_SPINLOCK(afs_vlocation_updates_lock);
26 static DEFINE_SPINLOCK(afs_vlocation_graveyard_lock);
27 static DECLARE_DELAYED_WORK(afs_vlocation_reap, afs_vlocation_reaper);
28 static DECLARE_DELAYED_WORK(afs_vlocation_update, afs_vlocation_updater);
29 static struct workqueue_struct *afs_vlocation_update_worker;
30
31 /*
32  * iterate through the VL servers in a cell until one of them admits knowing
33  * about the volume in question
34  */
35 static int afs_vlocation_access_vl_by_name(struct afs_vlocation *vl,
36                                            struct key *key,
37                                            struct afs_cache_vlocation *vldb)
38 {
39         struct afs_cell *cell = vl->cell;
40         struct in_addr addr;
41         int count, ret;
42
43         _enter("%s,%s", cell->name, vl->vldb.name);
44
45         down_write(&vl->cell->vl_sem);
46         ret = -ENOMEDIUM;
47         for (count = cell->vl_naddrs; count > 0; count--) {
48                 addr = cell->vl_addrs[cell->vl_curr_svix];
49
50                 _debug("CellServ[%hu]: %08x", cell->vl_curr_svix, addr.s_addr);
51
52                 /* attempt to access the VL server */
53                 ret = afs_vl_get_entry_by_name(&addr, key, vl->vldb.name, vldb,
54                                                &afs_sync_call);
55                 switch (ret) {
56                 case 0:
57                         goto out;
58                 case -ENOMEM:
59                 case -ENONET:
60                 case -ENETUNREACH:
61                 case -EHOSTUNREACH:
62                 case -ECONNREFUSED:
63                         if (ret == -ENOMEM || ret == -ENONET)
64                                 goto out;
65                         goto rotate;
66                 case -ENOMEDIUM:
67                         goto out;
68                 default:
69                         ret = -EIO;
70                         goto rotate;
71                 }
72
73                 /* rotate the server records upon lookup failure */
74         rotate:
75                 cell->vl_curr_svix++;
76                 cell->vl_curr_svix %= cell->vl_naddrs;
77         }
78
79 out:
80         up_write(&vl->cell->vl_sem);
81         _leave(" = %d", ret);
82         return ret;
83 }
84
85 /*
86  * iterate through the VL servers in a cell until one of them admits knowing
87  * about the volume in question
88  */
89 static int afs_vlocation_access_vl_by_id(struct afs_vlocation *vl,
90                                          struct key *key,
91                                          afs_volid_t volid,
92                                          afs_voltype_t voltype,
93                                          struct afs_cache_vlocation *vldb)
94 {
95         struct afs_cell *cell = vl->cell;
96         struct in_addr addr;
97         int count, ret;
98
99         _enter("%s,%x,%d,", cell->name, volid, voltype);
100
101         down_write(&vl->cell->vl_sem);
102         ret = -ENOMEDIUM;
103         for (count = cell->vl_naddrs; count > 0; count--) {
104                 addr = cell->vl_addrs[cell->vl_curr_svix];
105
106                 _debug("CellServ[%hu]: %08x", cell->vl_curr_svix, addr.s_addr);
107
108                 /* attempt to access the VL server */
109                 ret = afs_vl_get_entry_by_id(&addr, key, volid, voltype, vldb,
110                                              &afs_sync_call);
111                 switch (ret) {
112                 case 0:
113                         goto out;
114                 case -ENOMEM:
115                 case -ENONET:
116                 case -ENETUNREACH:
117                 case -EHOSTUNREACH:
118                 case -ECONNREFUSED:
119                         if (ret == -ENOMEM || ret == -ENONET)
120                                 goto out;
121                         goto rotate;
122                 case -EBUSY:
123                         vl->upd_busy_cnt++;
124                         if (vl->upd_busy_cnt <= 3) {
125                                 if (vl->upd_busy_cnt > 1) {
126                                         /* second+ BUSY - sleep a little bit */
127                                         set_current_state(TASK_UNINTERRUPTIBLE);
128                                         schedule_timeout(1);
129                                         __set_current_state(TASK_RUNNING);
130                                 }
131                                 continue;
132                         }
133                         break;
134                 case -ENOMEDIUM:
135                         vl->upd_rej_cnt++;
136                         goto rotate;
137                 default:
138                         ret = -EIO;
139                         goto rotate;
140                 }
141
142                 /* rotate the server records upon lookup failure */
143         rotate:
144                 cell->vl_curr_svix++;
145                 cell->vl_curr_svix %= cell->vl_naddrs;
146                 vl->upd_busy_cnt = 0;
147         }
148
149 out:
150         if (ret < 0 && vl->upd_rej_cnt > 0) {
151                 printk(KERN_NOTICE "kAFS:"
152                        " Active volume no longer valid '%s'\n",
153                        vl->vldb.name);
154                 vl->valid = 0;
155                 ret = -ENOMEDIUM;
156         }
157
158         up_write(&vl->cell->vl_sem);
159         _leave(" = %d", ret);
160         return ret;
161 }
162
163 /*
164  * allocate a volume location record
165  */
166 static struct afs_vlocation *afs_vlocation_alloc(struct afs_cell *cell,
167                                                  const char *name,
168                                                  size_t namesz)
169 {
170         struct afs_vlocation *vl;
171
172         vl = kzalloc(sizeof(struct afs_vlocation), GFP_KERNEL);
173         if (vl) {
174                 vl->cell = cell;
175                 vl->state = AFS_VL_NEW;
176                 atomic_set(&vl->usage, 1);
177                 INIT_LIST_HEAD(&vl->link);
178                 INIT_LIST_HEAD(&vl->grave);
179                 INIT_LIST_HEAD(&vl->update);
180                 init_waitqueue_head(&vl->waitq);
181                 rwlock_init(&vl->lock);
182                 memcpy(vl->vldb.name, name, namesz);
183         }
184
185         _leave(" = %p", vl);
186         return vl;
187 }
188
189 /*
190  * update record if we found it in the cache
191  */
192 static int afs_vlocation_update_record(struct afs_vlocation *vl,
193                                        struct key *key,
194                                        struct afs_cache_vlocation *vldb)
195 {
196         afs_voltype_t voltype;
197         afs_volid_t vid;
198         int ret;
199
200         /* try to look up a cached volume in the cell VL databases by ID */
201         _debug("Locally Cached: %s %02x { %08x(%x) %08x(%x) %08x(%x) }",
202                vl->vldb.name,
203                vl->vldb.vidmask,
204                ntohl(vl->vldb.servers[0].s_addr),
205                vl->vldb.srvtmask[0],
206                ntohl(vl->vldb.servers[1].s_addr),
207                vl->vldb.srvtmask[1],
208                ntohl(vl->vldb.servers[2].s_addr),
209                vl->vldb.srvtmask[2]);
210
211         _debug("Vids: %08x %08x %08x",
212                vl->vldb.vid[0],
213                vl->vldb.vid[1],
214                vl->vldb.vid[2]);
215
216         if (vl->vldb.vidmask & AFS_VOL_VTM_RW) {
217                 vid = vl->vldb.vid[0];
218                 voltype = AFSVL_RWVOL;
219         } else if (vl->vldb.vidmask & AFS_VOL_VTM_RO) {
220                 vid = vl->vldb.vid[1];
221                 voltype = AFSVL_ROVOL;
222         } else if (vl->vldb.vidmask & AFS_VOL_VTM_BAK) {
223                 vid = vl->vldb.vid[2];
224                 voltype = AFSVL_BACKVOL;
225         } else {
226                 BUG();
227                 vid = 0;
228                 voltype = 0;
229         }
230
231         /* contact the server to make sure the volume is still available
232          * - TODO: need to handle disconnected operation here
233          */
234         ret = afs_vlocation_access_vl_by_id(vl, key, vid, voltype, vldb);
235         switch (ret) {
236                 /* net error */
237         default:
238                 printk(KERN_WARNING "kAFS:"
239                        " failed to update volume '%s' (%x) up in '%s': %d\n",
240                        vl->vldb.name, vid, vl->cell->name, ret);
241                 _leave(" = %d", ret);
242                 return ret;
243
244                 /* pulled from local cache into memory */
245         case 0:
246                 _leave(" = 0");
247                 return 0;
248
249                 /* uh oh... looks like the volume got deleted */
250         case -ENOMEDIUM:
251                 printk(KERN_ERR "kAFS:"
252                        " volume '%s' (%x) does not exist '%s'\n",
253                        vl->vldb.name, vid, vl->cell->name);
254
255                 /* TODO: make existing record unavailable */
256                 _leave(" = %d", ret);
257                 return ret;
258         }
259 }
260
261 /*
262  * apply the update to a VL record
263  */
264 static void afs_vlocation_apply_update(struct afs_vlocation *vl,
265                                        struct afs_cache_vlocation *vldb)
266 {
267         _debug("Done VL Lookup: %s %02x { %08x(%x) %08x(%x) %08x(%x) }",
268                vldb->name, vldb->vidmask,
269                ntohl(vldb->servers[0].s_addr), vldb->srvtmask[0],
270                ntohl(vldb->servers[1].s_addr), vldb->srvtmask[1],
271                ntohl(vldb->servers[2].s_addr), vldb->srvtmask[2]);
272
273         _debug("Vids: %08x %08x %08x",
274                vldb->vid[0], vldb->vid[1], vldb->vid[2]);
275
276         if (strcmp(vldb->name, vl->vldb.name) != 0)
277                 printk(KERN_NOTICE "kAFS:"
278                        " name of volume '%s' changed to '%s' on server\n",
279                        vl->vldb.name, vldb->name);
280
281         vl->vldb = *vldb;
282
283 #ifdef AFS_CACHING_SUPPORT
284         /* update volume entry in local cache */
285         cachefs_update_cookie(vl->cache);
286 #endif
287 }
288
289 /*
290  * fill in a volume location record, consulting the cache and the VL server
291  * both
292  */
293 static int afs_vlocation_fill_in_record(struct afs_vlocation *vl,
294                                         struct key *key)
295 {
296         struct afs_cache_vlocation vldb;
297         int ret;
298
299         _enter("");
300
301         ASSERTCMP(vl->valid, ==, 0);
302
303         memset(&vldb, 0, sizeof(vldb));
304
305         /* see if we have an in-cache copy (will set vl->valid if there is) */
306 #ifdef AFS_CACHING_SUPPORT
307         cachefs_acquire_cookie(cell->cache,
308                                &afs_volume_cache_index_def,
309                                vlocation,
310                                &vl->cache);
311 #endif
312
313         if (vl->valid) {
314                 /* try to update a known volume in the cell VL databases by
315                  * ID as the name may have changed */
316                 _debug("found in cache");
317                 ret = afs_vlocation_update_record(vl, key, &vldb);
318         } else {
319                 /* try to look up an unknown volume in the cell VL databases by
320                  * name */
321                 ret = afs_vlocation_access_vl_by_name(vl, key, &vldb);
322                 if (ret < 0) {
323                         printk("kAFS: failed to locate '%s' in cell '%s'\n",
324                                vl->vldb.name, vl->cell->name);
325                         return ret;
326                 }
327         }
328
329         afs_vlocation_apply_update(vl, &vldb);
330         _leave(" = 0");
331         return 0;
332 }
333
334 /*
335  * queue a vlocation record for updates
336  */
337 void afs_vlocation_queue_for_updates(struct afs_vlocation *vl)
338 {
339         struct afs_vlocation *xvl;
340
341         /* wait at least 10 minutes before updating... */
342         vl->update_at = get_seconds() + afs_vlocation_update_timeout;
343
344         spin_lock(&afs_vlocation_updates_lock);
345
346         if (!list_empty(&afs_vlocation_updates)) {
347                 /* ... but wait at least 1 second more than the newest record
348                  * already queued so that we don't spam the VL server suddenly
349                  * with lots of requests
350                  */
351                 xvl = list_entry(afs_vlocation_updates.prev,
352                                  struct afs_vlocation, update);
353                 if (vl->update_at <= xvl->update_at)
354                         vl->update_at = xvl->update_at + 1;
355         } else {
356                 queue_delayed_work(afs_vlocation_update_worker,
357                                    &afs_vlocation_update,
358                                    afs_vlocation_update_timeout * HZ);
359         }
360
361         list_add_tail(&vl->update, &afs_vlocation_updates);
362         spin_unlock(&afs_vlocation_updates_lock);
363 }
364
365 /*
366  * lookup volume location
367  * - iterate through the VL servers in a cell until one of them admits knowing
368  *   about the volume in question
369  * - lookup in the local cache if not able to find on the VL server
370  * - insert/update in the local cache if did get a VL response
371  */
372 struct afs_vlocation *afs_vlocation_lookup(struct afs_cell *cell,
373                                            struct key *key,
374                                            const char *name,
375                                            size_t namesz)
376 {
377         struct afs_vlocation *vl;
378         int ret;
379
380         _enter("{%s},{%x},%*.*s,%zu",
381                cell->name, key_serial(key),
382                (int) namesz, (int) namesz, name, namesz);
383
384         if (namesz > sizeof(vl->vldb.name)) {
385                 _leave(" = -ENAMETOOLONG");
386                 return ERR_PTR(-ENAMETOOLONG);
387         }
388
389         /* see if we have an in-memory copy first */
390         down_write(&cell->vl_sem);
391         spin_lock(&cell->vl_lock);
392         list_for_each_entry(vl, &cell->vl_list, link) {
393                 if (vl->vldb.name[namesz] != '\0')
394                         continue;
395                 if (memcmp(vl->vldb.name, name, namesz) == 0)
396                         goto found_in_memory;
397         }
398         spin_unlock(&cell->vl_lock);
399
400         /* not in the cell's in-memory lists - create a new record */
401         vl = afs_vlocation_alloc(cell, name, namesz);
402         if (!vl) {
403                 up_write(&cell->vl_sem);
404                 return ERR_PTR(-ENOMEM);
405         }
406
407         afs_get_cell(cell);
408
409         list_add_tail(&vl->link, &cell->vl_list);
410         vl->state = AFS_VL_CREATING;
411         up_write(&cell->vl_sem);
412
413 fill_in_record:
414         ret = afs_vlocation_fill_in_record(vl, key);
415         if (ret < 0)
416                 goto error_abandon;
417         vl->state = AFS_VL_VALID;
418         wake_up(&vl->waitq);
419
420         /* schedule for regular updates */
421         afs_vlocation_queue_for_updates(vl);
422         goto success;
423
424 found_in_memory:
425         /* found in memory */
426         _debug("found in memory");
427         atomic_inc(&vl->usage);
428         spin_unlock(&cell->vl_lock);
429         if (!list_empty(&vl->grave)) {
430                 spin_lock(&afs_vlocation_graveyard_lock);
431                 list_del_init(&vl->grave);
432                 spin_unlock(&afs_vlocation_graveyard_lock);
433         }
434         up_write(&cell->vl_sem);
435
436         /* see if it was an abandoned record that we might try filling in */
437         while (vl->state != AFS_VL_VALID) {
438                 afs_vlocation_state_t state = vl->state;
439
440                 _debug("invalid [state %d]", state);
441
442                 if ((state == AFS_VL_NEW || state == AFS_VL_NO_VOLUME)) {
443                         if (cmpxchg(&vl->state, state, AFS_VL_CREATING) ==
444                             state)
445                                 goto fill_in_record;
446                         continue;
447                 }
448
449                 /* must now wait for creation or update by someone else to
450                  * complete */
451                 _debug("wait");
452
453                 ret = wait_event_interruptible(
454                         vl->waitq,
455                         vl->state == AFS_VL_NEW ||
456                         vl->state == AFS_VL_VALID ||
457                         vl->state == AFS_VL_NO_VOLUME);
458                 if (ret < 0)
459                         goto error;
460         }
461
462 success:
463         _leave(" = %p",vl);
464         return vl;
465
466 error_abandon:
467         vl->state = AFS_VL_NEW;
468         wake_up(&vl->waitq);
469 error:
470         ASSERT(vl != NULL);
471         afs_put_vlocation(vl);
472         _leave(" = %d", ret);
473         return ERR_PTR(ret);
474 }
475
476 /*
477  * finish using a volume location record
478  */
479 void afs_put_vlocation(struct afs_vlocation *vl)
480 {
481         if (!vl)
482                 return;
483
484         _enter("%s", vl->vldb.name);
485
486         ASSERTCMP(atomic_read(&vl->usage), >, 0);
487
488         if (likely(!atomic_dec_and_test(&vl->usage))) {
489                 _leave("");
490                 return;
491         }
492
493         spin_lock(&afs_vlocation_graveyard_lock);
494         if (atomic_read(&vl->usage) == 0) {
495                 _debug("buried");
496                 list_move_tail(&vl->grave, &afs_vlocation_graveyard);
497                 vl->time_of_death = get_seconds();
498                 schedule_delayed_work(&afs_vlocation_reap,
499                                       afs_vlocation_timeout * HZ);
500
501                 /* suspend updates on this record */
502                 if (!list_empty(&vl->update)) {
503                         spin_lock(&afs_vlocation_updates_lock);
504                         list_del_init(&vl->update);
505                         spin_unlock(&afs_vlocation_updates_lock);
506                 }
507         }
508         spin_unlock(&afs_vlocation_graveyard_lock);
509         _leave(" [killed?]");
510 }
511
512 /*
513  * destroy a dead volume location record
514  */
515 static void afs_vlocation_destroy(struct afs_vlocation *vl)
516 {
517         _enter("%p", vl);
518
519 #ifdef AFS_CACHING_SUPPORT
520         cachefs_relinquish_cookie(vl->cache, 0);
521 #endif
522
523         afs_put_cell(vl->cell);
524         kfree(vl);
525 }
526
527 /*
528  * reap dead volume location records
529  */
530 static void afs_vlocation_reaper(struct work_struct *work)
531 {
532         LIST_HEAD(corpses);
533         struct afs_vlocation *vl;
534         unsigned long delay, expiry;
535         time_t now;
536
537         _enter("");
538
539         now = get_seconds();
540         spin_lock(&afs_vlocation_graveyard_lock);
541
542         while (!list_empty(&afs_vlocation_graveyard)) {
543                 vl = list_entry(afs_vlocation_graveyard.next,
544                                 struct afs_vlocation, grave);
545
546                 _debug("check %p", vl);
547
548                 /* the queue is ordered most dead first */
549                 expiry = vl->time_of_death + afs_vlocation_timeout;
550                 if (expiry > now) {
551                         delay = (expiry - now) * HZ;
552                         _debug("delay %lu", delay);
553                         if (!schedule_delayed_work(&afs_vlocation_reap,
554                                                    delay)) {
555                                 cancel_delayed_work(&afs_vlocation_reap);
556                                 schedule_delayed_work(&afs_vlocation_reap,
557                                                       delay);
558                         }
559                         break;
560                 }
561
562                 spin_lock(&vl->cell->vl_lock);
563                 if (atomic_read(&vl->usage) > 0) {
564                         _debug("no reap");
565                         list_del_init(&vl->grave);
566                 } else {
567                         _debug("reap");
568                         list_move_tail(&vl->grave, &corpses);
569                         list_del_init(&vl->link);
570                 }
571                 spin_unlock(&vl->cell->vl_lock);
572         }
573
574         spin_unlock(&afs_vlocation_graveyard_lock);
575
576         /* now reap the corpses we've extracted */
577         while (!list_empty(&corpses)) {
578                 vl = list_entry(corpses.next, struct afs_vlocation, grave);
579                 list_del(&vl->grave);
580                 afs_vlocation_destroy(vl);
581         }
582
583         _leave("");
584 }
585
586 /*
587  * initialise the VL update process
588  */
589 int __init afs_vlocation_update_init(void)
590 {
591         afs_vlocation_update_worker =
592                 create_singlethread_workqueue("kafs_vlupdated");
593         return afs_vlocation_update_worker ? 0 : -ENOMEM;
594 }
595
596 /*
597  * discard all the volume location records for rmmod
598  */
599 void __exit afs_vlocation_purge(void)
600 {
601         afs_vlocation_timeout = 0;
602
603         spin_lock(&afs_vlocation_updates_lock);
604         list_del_init(&afs_vlocation_updates);
605         spin_unlock(&afs_vlocation_updates_lock);
606         cancel_delayed_work(&afs_vlocation_update);
607         queue_delayed_work(afs_vlocation_update_worker,
608                            &afs_vlocation_update, 0);
609         destroy_workqueue(afs_vlocation_update_worker);
610
611         cancel_delayed_work(&afs_vlocation_reap);
612         schedule_delayed_work(&afs_vlocation_reap, 0);
613 }
614
615 /*
616  * update a volume location
617  */
618 static void afs_vlocation_updater(struct work_struct *work)
619 {
620         struct afs_cache_vlocation vldb;
621         struct afs_vlocation *vl, *xvl;
622         time_t now;
623         long timeout;
624         int ret;
625
626         _enter("");
627
628         now = get_seconds();
629
630         /* find a record to update */
631         spin_lock(&afs_vlocation_updates_lock);
632         for (;;) {
633                 if (list_empty(&afs_vlocation_updates)) {
634                         spin_unlock(&afs_vlocation_updates_lock);
635                         _leave(" [nothing]");
636                         return;
637                 }
638
639                 vl = list_entry(afs_vlocation_updates.next,
640                                 struct afs_vlocation, update);
641                 if (atomic_read(&vl->usage) > 0)
642                         break;
643                 list_del_init(&vl->update);
644         }
645
646         timeout = vl->update_at - now;
647         if (timeout > 0) {
648                 queue_delayed_work(afs_vlocation_update_worker,
649                                    &afs_vlocation_update, timeout * HZ);
650                 spin_unlock(&afs_vlocation_updates_lock);
651                 _leave(" [nothing]");
652                 return;
653         }
654
655         list_del_init(&vl->update);
656         atomic_inc(&vl->usage);
657         spin_unlock(&afs_vlocation_updates_lock);
658
659         /* we can now perform the update */
660         _debug("update %s", vl->vldb.name);
661         vl->state = AFS_VL_UPDATING;
662         vl->upd_rej_cnt = 0;
663         vl->upd_busy_cnt = 0;
664
665         ret = afs_vlocation_update_record(vl, NULL, &vldb);
666         switch (ret) {
667         case 0:
668                 afs_vlocation_apply_update(vl, &vldb);
669                 vl->state = AFS_VL_VALID;
670                 break;
671         case -ENOMEDIUM:
672                 vl->state = AFS_VL_VOLUME_DELETED;
673                 break;
674         default:
675                 vl->state = AFS_VL_UNCERTAIN;
676                 break;
677         }
678
679         /* and then reschedule */
680         _debug("reschedule");
681         vl->update_at = get_seconds() + afs_vlocation_update_timeout;
682
683         spin_lock(&afs_vlocation_updates_lock);
684
685         if (!list_empty(&afs_vlocation_updates)) {
686                 /* next update in 10 minutes, but wait at least 1 second more
687                  * than the newest record already queued so that we don't spam
688                  * the VL server suddenly with lots of requests
689                  */
690                 xvl = list_entry(afs_vlocation_updates.prev,
691                                  struct afs_vlocation, update);
692                 if (vl->update_at <= xvl->update_at)
693                         vl->update_at = xvl->update_at + 1;
694                 xvl = list_entry(afs_vlocation_updates.next,
695                                  struct afs_vlocation, update);
696                 timeout = xvl->update_at - now;
697                 if (timeout < 0)
698                         timeout = 0;
699         } else {
700                 timeout = afs_vlocation_update_timeout;
701         }
702
703         ASSERT(list_empty(&vl->update));
704
705         list_add_tail(&vl->update, &afs_vlocation_updates);
706
707         _debug("timeout %ld", timeout);
708         queue_delayed_work(afs_vlocation_update_worker,
709                            &afs_vlocation_update, timeout * HZ);
710         spin_unlock(&afs_vlocation_updates_lock);
711         afs_put_vlocation(vl);
712 }