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6
7
8#include <linux/slab.h>
9#include <linux/key.h>
10#include <linux/ctype.h>
11#include <linux/dns_resolver.h>
12#include <linux/sched.h>
13#include <linux/inet.h>
14#include <linux/namei.h>
15#include <keys/rxrpc-type.h>
16#include "internal.h"
17
18static unsigned __read_mostly afs_cell_gc_delay = 10;
19static unsigned __read_mostly afs_cell_min_ttl = 10 * 60;
20static unsigned __read_mostly afs_cell_max_ttl = 24 * 60 * 60;
21static atomic_t cell_debug_id;
22
23static void afs_queue_cell_manager(struct afs_net *);
24static void afs_manage_cell_work(struct work_struct *);
25
26static void afs_dec_cells_outstanding(struct afs_net *net)
27{
28 if (atomic_dec_and_test(&net->cells_outstanding))
29 wake_up_var(&net->cells_outstanding);
30}
31
32
33
34
35
36static void afs_set_cell_timer(struct afs_net *net, time64_t delay)
37{
38 if (net->live) {
39 atomic_inc(&net->cells_outstanding);
40 if (timer_reduce(&net->cells_timer, jiffies + delay * HZ))
41 afs_dec_cells_outstanding(net);
42 } else {
43 afs_queue_cell_manager(net);
44 }
45}
46
47
48
49
50
51static struct afs_cell *afs_find_cell_locked(struct afs_net *net,
52 const char *name, unsigned int namesz,
53 enum afs_cell_trace reason)
54{
55 struct afs_cell *cell = NULL;
56 struct rb_node *p;
57 int n;
58
59 _enter("%*.*s", namesz, namesz, name);
60
61 if (name && namesz == 0)
62 return ERR_PTR(-EINVAL);
63 if (namesz > AFS_MAXCELLNAME)
64 return ERR_PTR(-ENAMETOOLONG);
65
66 if (!name) {
67 cell = net->ws_cell;
68 if (!cell)
69 return ERR_PTR(-EDESTADDRREQ);
70 goto found;
71 }
72
73 p = net->cells.rb_node;
74 while (p) {
75 cell = rb_entry(p, struct afs_cell, net_node);
76
77 n = strncasecmp(cell->name, name,
78 min_t(size_t, cell->name_len, namesz));
79 if (n == 0)
80 n = cell->name_len - namesz;
81 if (n < 0)
82 p = p->rb_left;
83 else if (n > 0)
84 p = p->rb_right;
85 else
86 goto found;
87 }
88
89 return ERR_PTR(-ENOENT);
90
91found:
92 return afs_use_cell(cell, reason);
93}
94
95
96
97
98struct afs_cell *afs_find_cell(struct afs_net *net,
99 const char *name, unsigned int namesz,
100 enum afs_cell_trace reason)
101{
102 struct afs_cell *cell;
103
104 down_read(&net->cells_lock);
105 cell = afs_find_cell_locked(net, name, namesz, reason);
106 up_read(&net->cells_lock);
107 return cell;
108}
109
110
111
112
113
114static struct afs_cell *afs_alloc_cell(struct afs_net *net,
115 const char *name, unsigned int namelen,
116 const char *addresses)
117{
118 struct afs_vlserver_list *vllist;
119 struct afs_cell *cell;
120 int i, ret;
121
122 ASSERT(name);
123 if (namelen == 0)
124 return ERR_PTR(-EINVAL);
125 if (namelen > AFS_MAXCELLNAME) {
126 _leave(" = -ENAMETOOLONG");
127 return ERR_PTR(-ENAMETOOLONG);
128 }
129
130
131
132
133 if (name[0] == '.')
134 return ERR_PTR(-EINVAL);
135 for (i = 0; i < namelen; i++) {
136 char ch = name[i];
137 if (!isprint(ch) || ch == '/' || ch == '@')
138 return ERR_PTR(-EINVAL);
139 }
140
141 _enter("%*.*s,%s", namelen, namelen, name, addresses);
142
143 cell = kzalloc(sizeof(struct afs_cell), GFP_KERNEL);
144 if (!cell) {
145 _leave(" = -ENOMEM");
146 return ERR_PTR(-ENOMEM);
147 }
148
149 cell->name = kmalloc(namelen + 1, GFP_KERNEL);
150 if (!cell->name) {
151 kfree(cell);
152 return ERR_PTR(-ENOMEM);
153 }
154
155 cell->net = net;
156 cell->name_len = namelen;
157 for (i = 0; i < namelen; i++)
158 cell->name[i] = tolower(name[i]);
159 cell->name[i] = 0;
160
161 atomic_set(&cell->ref, 1);
162 atomic_set(&cell->active, 0);
163 INIT_WORK(&cell->manager, afs_manage_cell_work);
164 cell->volumes = RB_ROOT;
165 INIT_HLIST_HEAD(&cell->proc_volumes);
166 seqlock_init(&cell->volume_lock);
167 cell->fs_servers = RB_ROOT;
168 seqlock_init(&cell->fs_lock);
169 INIT_LIST_HEAD(&cell->fs_open_mmaps);
170 init_rwsem(&cell->fs_open_mmaps_lock);
171 rwlock_init(&cell->vl_servers_lock);
172 cell->flags = (1 << AFS_CELL_FL_CHECK_ALIAS);
173
174
175
176
177 if (addresses) {
178 vllist = afs_parse_text_addrs(net,
179 addresses, strlen(addresses), ':',
180 VL_SERVICE, AFS_VL_PORT);
181 if (IS_ERR(vllist)) {
182 ret = PTR_ERR(vllist);
183 goto parse_failed;
184 }
185
186 vllist->source = DNS_RECORD_FROM_CONFIG;
187 vllist->status = DNS_LOOKUP_NOT_DONE;
188 cell->dns_expiry = TIME64_MAX;
189 } else {
190 ret = -ENOMEM;
191 vllist = afs_alloc_vlserver_list(0);
192 if (!vllist)
193 goto error;
194 vllist->source = DNS_RECORD_UNAVAILABLE;
195 vllist->status = DNS_LOOKUP_NOT_DONE;
196 cell->dns_expiry = ktime_get_real_seconds();
197 }
198
199 rcu_assign_pointer(cell->vl_servers, vllist);
200
201 cell->dns_source = vllist->source;
202 cell->dns_status = vllist->status;
203 smp_store_release(&cell->dns_lookup_count, 1);
204 atomic_inc(&net->cells_outstanding);
205 cell->debug_id = atomic_inc_return(&cell_debug_id);
206 trace_afs_cell(cell->debug_id, 1, 0, afs_cell_trace_alloc);
207
208 _leave(" = %p", cell);
209 return cell;
210
211parse_failed:
212 if (ret == -EINVAL)
213 printk(KERN_ERR "kAFS: bad VL server IP address\n");
214error:
215 kfree(cell->name);
216 kfree(cell);
217 _leave(" = %d", ret);
218 return ERR_PTR(ret);
219}
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234struct afs_cell *afs_lookup_cell(struct afs_net *net,
235 const char *name, unsigned int namesz,
236 const char *vllist, bool excl)
237{
238 struct afs_cell *cell, *candidate, *cursor;
239 struct rb_node *parent, **pp;
240 enum afs_cell_state state;
241 int ret, n;
242
243 _enter("%s,%s", name, vllist);
244
245 if (!excl) {
246 cell = afs_find_cell(net, name, namesz, afs_cell_trace_use_lookup);
247 if (!IS_ERR(cell))
248 goto wait_for_cell;
249 }
250
251
252
253
254
255
256
257
258 candidate = afs_alloc_cell(net, name, namesz, vllist);
259 if (IS_ERR(candidate)) {
260 _leave(" = %ld", PTR_ERR(candidate));
261 return candidate;
262 }
263
264
265
266
267 down_write(&net->cells_lock);
268
269 pp = &net->cells.rb_node;
270 parent = NULL;
271 while (*pp) {
272 parent = *pp;
273 cursor = rb_entry(parent, struct afs_cell, net_node);
274
275 n = strncasecmp(cursor->name, name,
276 min_t(size_t, cursor->name_len, namesz));
277 if (n == 0)
278 n = cursor->name_len - namesz;
279 if (n < 0)
280 pp = &(*pp)->rb_left;
281 else if (n > 0)
282 pp = &(*pp)->rb_right;
283 else
284 goto cell_already_exists;
285 }
286
287 cell = candidate;
288 candidate = NULL;
289 atomic_set(&cell->active, 2);
290 trace_afs_cell(cell->debug_id, atomic_read(&cell->ref), 2, afs_cell_trace_insert);
291 rb_link_node_rcu(&cell->net_node, parent, pp);
292 rb_insert_color(&cell->net_node, &net->cells);
293 up_write(&net->cells_lock);
294
295 afs_queue_cell(cell, afs_cell_trace_get_queue_new);
296
297wait_for_cell:
298 trace_afs_cell(cell->debug_id, atomic_read(&cell->ref), atomic_read(&cell->active),
299 afs_cell_trace_wait);
300 _debug("wait_for_cell");
301 wait_var_event(&cell->state,
302 ({
303 state = smp_load_acquire(&cell->state);
304 state == AFS_CELL_ACTIVE || state == AFS_CELL_REMOVED;
305 }));
306
307
308 if (state == AFS_CELL_REMOVED) {
309 ret = cell->error;
310 goto error;
311 }
312
313 _leave(" = %p [cell]", cell);
314 return cell;
315
316cell_already_exists:
317 _debug("cell exists");
318 cell = cursor;
319 if (excl) {
320 ret = -EEXIST;
321 } else {
322 afs_use_cell(cursor, afs_cell_trace_use_lookup);
323 ret = 0;
324 }
325 up_write(&net->cells_lock);
326 if (candidate)
327 afs_put_cell(candidate, afs_cell_trace_put_candidate);
328 if (ret == 0)
329 goto wait_for_cell;
330 goto error_noput;
331error:
332 afs_unuse_cell(net, cell, afs_cell_trace_unuse_lookup);
333error_noput:
334 _leave(" = %d [error]", ret);
335 return ERR_PTR(ret);
336}
337
338
339
340
341
342
343int afs_cell_init(struct afs_net *net, const char *rootcell)
344{
345 struct afs_cell *old_root, *new_root;
346 const char *cp, *vllist;
347 size_t len;
348
349 _enter("");
350
351 if (!rootcell) {
352
353
354
355 _leave(" = 0 [no root]");
356 return 0;
357 }
358
359 cp = strchr(rootcell, ':');
360 if (!cp) {
361 _debug("kAFS: no VL server IP addresses specified");
362 vllist = NULL;
363 len = strlen(rootcell);
364 } else {
365 vllist = cp + 1;
366 len = cp - rootcell;
367 }
368
369
370 new_root = afs_lookup_cell(net, rootcell, len, vllist, false);
371 if (IS_ERR(new_root)) {
372 _leave(" = %ld", PTR_ERR(new_root));
373 return PTR_ERR(new_root);
374 }
375
376 if (!test_and_set_bit(AFS_CELL_FL_NO_GC, &new_root->flags))
377 afs_use_cell(new_root, afs_cell_trace_use_pin);
378
379
380 down_write(&net->cells_lock);
381 afs_see_cell(new_root, afs_cell_trace_see_ws);
382 old_root = net->ws_cell;
383 net->ws_cell = new_root;
384 up_write(&net->cells_lock);
385
386 afs_unuse_cell(net, old_root, afs_cell_trace_unuse_ws);
387 _leave(" = 0");
388 return 0;
389}
390
391
392
393
394static int afs_update_cell(struct afs_cell *cell)
395{
396 struct afs_vlserver_list *vllist, *old = NULL, *p;
397 unsigned int min_ttl = READ_ONCE(afs_cell_min_ttl);
398 unsigned int max_ttl = READ_ONCE(afs_cell_max_ttl);
399 time64_t now, expiry = 0;
400 int ret = 0;
401
402 _enter("%s", cell->name);
403
404 vllist = afs_dns_query(cell, &expiry);
405 if (IS_ERR(vllist)) {
406 ret = PTR_ERR(vllist);
407
408 _debug("%s: fail %d", cell->name, ret);
409 if (ret == -ENOMEM)
410 goto out_wake;
411
412 ret = -ENOMEM;
413 vllist = afs_alloc_vlserver_list(0);
414 if (!vllist)
415 goto out_wake;
416
417 switch (ret) {
418 case -ENODATA:
419 case -EDESTADDRREQ:
420 vllist->status = DNS_LOOKUP_GOT_NOT_FOUND;
421 break;
422 case -EAGAIN:
423 case -ECONNREFUSED:
424 vllist->status = DNS_LOOKUP_GOT_TEMP_FAILURE;
425 break;
426 default:
427 vllist->status = DNS_LOOKUP_GOT_LOCAL_FAILURE;
428 break;
429 }
430 }
431
432 _debug("%s: got list %d %d", cell->name, vllist->source, vllist->status);
433 cell->dns_status = vllist->status;
434
435 now = ktime_get_real_seconds();
436 if (min_ttl > max_ttl)
437 max_ttl = min_ttl;
438 if (expiry < now + min_ttl)
439 expiry = now + min_ttl;
440 else if (expiry > now + max_ttl)
441 expiry = now + max_ttl;
442
443 _debug("%s: status %d", cell->name, vllist->status);
444 if (vllist->source == DNS_RECORD_UNAVAILABLE) {
445 switch (vllist->status) {
446 case DNS_LOOKUP_GOT_NOT_FOUND:
447
448
449
450 cell->dns_expiry = expiry;
451 break;
452
453 case DNS_LOOKUP_BAD:
454 case DNS_LOOKUP_GOT_LOCAL_FAILURE:
455 case DNS_LOOKUP_GOT_TEMP_FAILURE:
456 case DNS_LOOKUP_GOT_NS_FAILURE:
457 default:
458 cell->dns_expiry = now + 10;
459 break;
460 }
461 } else {
462 cell->dns_expiry = expiry;
463 }
464
465
466
467
468 write_lock(&cell->vl_servers_lock);
469 p = rcu_dereference_protected(cell->vl_servers, true);
470 if (vllist->nr_servers > 0 || p->nr_servers == 0) {
471 rcu_assign_pointer(cell->vl_servers, vllist);
472 cell->dns_source = vllist->source;
473 old = p;
474 }
475 write_unlock(&cell->vl_servers_lock);
476 afs_put_vlserverlist(cell->net, old);
477
478out_wake:
479 smp_store_release(&cell->dns_lookup_count,
480 cell->dns_lookup_count + 1);
481 wake_up_var(&cell->dns_lookup_count);
482 _leave(" = %d", ret);
483 return ret;
484}
485
486
487
488
489static void afs_cell_destroy(struct rcu_head *rcu)
490{
491 struct afs_cell *cell = container_of(rcu, struct afs_cell, rcu);
492 struct afs_net *net = cell->net;
493 int u;
494
495 _enter("%p{%s}", cell, cell->name);
496
497 u = atomic_read(&cell->ref);
498 ASSERTCMP(u, ==, 0);
499 trace_afs_cell(cell->debug_id, u, atomic_read(&cell->active), afs_cell_trace_free);
500
501 afs_put_vlserverlist(net, rcu_access_pointer(cell->vl_servers));
502 afs_unuse_cell(net, cell->alias_of, afs_cell_trace_unuse_alias);
503 key_put(cell->anonymous_key);
504 kfree(cell->name);
505 kfree(cell);
506
507 afs_dec_cells_outstanding(net);
508 _leave(" [destroyed]");
509}
510
511
512
513
514static void afs_queue_cell_manager(struct afs_net *net)
515{
516 int outstanding = atomic_inc_return(&net->cells_outstanding);
517
518 _enter("%d", outstanding);
519
520 if (!queue_work(afs_wq, &net->cells_manager))
521 afs_dec_cells_outstanding(net);
522}
523
524
525
526
527
528void afs_cells_timer(struct timer_list *timer)
529{
530 struct afs_net *net = container_of(timer, struct afs_net, cells_timer);
531
532 _enter("");
533 if (!queue_work(afs_wq, &net->cells_manager))
534 afs_dec_cells_outstanding(net);
535}
536
537
538
539
540struct afs_cell *afs_get_cell(struct afs_cell *cell, enum afs_cell_trace reason)
541{
542 int u;
543
544 if (atomic_read(&cell->ref) <= 0)
545 BUG();
546
547 u = atomic_inc_return(&cell->ref);
548 trace_afs_cell(cell->debug_id, u, atomic_read(&cell->active), reason);
549 return cell;
550}
551
552
553
554
555void afs_put_cell(struct afs_cell *cell, enum afs_cell_trace reason)
556{
557 if (cell) {
558 unsigned int debug_id = cell->debug_id;
559 unsigned int u, a;
560
561 a = atomic_read(&cell->active);
562 u = atomic_dec_return(&cell->ref);
563 trace_afs_cell(debug_id, u, a, reason);
564 if (u == 0) {
565 a = atomic_read(&cell->active);
566 WARN(a != 0, "Cell active count %u > 0\n", a);
567 call_rcu(&cell->rcu, afs_cell_destroy);
568 }
569 }
570}
571
572
573
574
575struct afs_cell *afs_use_cell(struct afs_cell *cell, enum afs_cell_trace reason)
576{
577 int u, a;
578
579 if (atomic_read(&cell->ref) <= 0)
580 BUG();
581
582 u = atomic_read(&cell->ref);
583 a = atomic_inc_return(&cell->active);
584 trace_afs_cell(cell->debug_id, u, a, reason);
585 return cell;
586}
587
588
589
590
591
592void afs_unuse_cell(struct afs_net *net, struct afs_cell *cell, enum afs_cell_trace reason)
593{
594 unsigned int debug_id;
595 time64_t now, expire_delay;
596 int u, a;
597
598 if (!cell)
599 return;
600
601 _enter("%s", cell->name);
602
603 now = ktime_get_real_seconds();
604 cell->last_inactive = now;
605 expire_delay = 0;
606 if (cell->vl_servers->nr_servers)
607 expire_delay = afs_cell_gc_delay;
608
609 debug_id = cell->debug_id;
610 u = atomic_read(&cell->ref);
611 a = atomic_dec_return(&cell->active);
612 trace_afs_cell(debug_id, u, a, reason);
613 WARN_ON(a == 0);
614 if (a == 1)
615
616 afs_set_cell_timer(net, expire_delay);
617}
618
619
620
621
622void afs_see_cell(struct afs_cell *cell, enum afs_cell_trace reason)
623{
624 int u, a;
625
626 u = atomic_read(&cell->ref);
627 a = atomic_read(&cell->active);
628 trace_afs_cell(cell->debug_id, u, a, reason);
629}
630
631
632
633
634void afs_queue_cell(struct afs_cell *cell, enum afs_cell_trace reason)
635{
636 afs_get_cell(cell, reason);
637 if (!queue_work(afs_wq, &cell->manager))
638 afs_put_cell(cell, afs_cell_trace_put_queue_fail);
639}
640
641
642
643
644static int afs_alloc_anon_key(struct afs_cell *cell)
645{
646 struct key *key;
647 char keyname[4 + AFS_MAXCELLNAME + 1], *cp, *dp;
648
649
650 memcpy(keyname, "afs@", 4);
651 dp = keyname + 4;
652 cp = cell->name;
653 do {
654 *dp++ = tolower(*cp);
655 } while (*cp++);
656
657 key = rxrpc_get_null_key(keyname);
658 if (IS_ERR(key))
659 return PTR_ERR(key);
660
661 cell->anonymous_key = key;
662
663 _debug("anon key %p{%x}",
664 cell->anonymous_key, key_serial(cell->anonymous_key));
665 return 0;
666}
667
668
669
670
671static int afs_activate_cell(struct afs_net *net, struct afs_cell *cell)
672{
673 struct hlist_node **p;
674 struct afs_cell *pcell;
675 int ret;
676
677 if (!cell->anonymous_key) {
678 ret = afs_alloc_anon_key(cell);
679 if (ret < 0)
680 return ret;
681 }
682
683#ifdef CONFIG_AFS_FSCACHE
684 cell->cache = fscache_acquire_cookie(afs_cache_netfs.primary_index,
685 &afs_cell_cache_index_def,
686 cell->name, strlen(cell->name),
687 NULL, 0,
688 cell, 0, true);
689#endif
690 ret = afs_proc_cell_setup(cell);
691 if (ret < 0)
692 return ret;
693
694 mutex_lock(&net->proc_cells_lock);
695 for (p = &net->proc_cells.first; *p; p = &(*p)->next) {
696 pcell = hlist_entry(*p, struct afs_cell, proc_link);
697 if (strcmp(cell->name, pcell->name) < 0)
698 break;
699 }
700
701 cell->proc_link.pprev = p;
702 cell->proc_link.next = *p;
703 rcu_assign_pointer(*p, &cell->proc_link.next);
704 if (cell->proc_link.next)
705 cell->proc_link.next->pprev = &cell->proc_link.next;
706
707 afs_dynroot_mkdir(net, cell);
708 mutex_unlock(&net->proc_cells_lock);
709 return 0;
710}
711
712
713
714
715static void afs_deactivate_cell(struct afs_net *net, struct afs_cell *cell)
716{
717 _enter("%s", cell->name);
718
719 afs_proc_cell_remove(cell);
720
721 mutex_lock(&net->proc_cells_lock);
722 hlist_del_rcu(&cell->proc_link);
723 afs_dynroot_rmdir(net, cell);
724 mutex_unlock(&net->proc_cells_lock);
725
726#ifdef CONFIG_AFS_FSCACHE
727 fscache_relinquish_cookie(cell->cache, NULL, false);
728 cell->cache = NULL;
729#endif
730
731 _leave("");
732}
733
734
735
736
737
738static void afs_manage_cell(struct afs_cell *cell)
739{
740 struct afs_net *net = cell->net;
741 int ret, active;
742
743 _enter("%s", cell->name);
744
745again:
746 _debug("state %u", cell->state);
747 switch (cell->state) {
748 case AFS_CELL_INACTIVE:
749 case AFS_CELL_FAILED:
750 down_write(&net->cells_lock);
751 active = 1;
752 if (atomic_try_cmpxchg_relaxed(&cell->active, &active, 0)) {
753 rb_erase(&cell->net_node, &net->cells);
754 trace_afs_cell(cell->debug_id, atomic_read(&cell->ref), 0,
755 afs_cell_trace_unuse_delete);
756 smp_store_release(&cell->state, AFS_CELL_REMOVED);
757 }
758 up_write(&net->cells_lock);
759 if (cell->state == AFS_CELL_REMOVED) {
760 wake_up_var(&cell->state);
761 goto final_destruction;
762 }
763 if (cell->state == AFS_CELL_FAILED)
764 goto done;
765 smp_store_release(&cell->state, AFS_CELL_UNSET);
766 wake_up_var(&cell->state);
767 goto again;
768
769 case AFS_CELL_UNSET:
770 smp_store_release(&cell->state, AFS_CELL_ACTIVATING);
771 wake_up_var(&cell->state);
772 goto again;
773
774 case AFS_CELL_ACTIVATING:
775 ret = afs_activate_cell(net, cell);
776 if (ret < 0)
777 goto activation_failed;
778
779 smp_store_release(&cell->state, AFS_CELL_ACTIVE);
780 wake_up_var(&cell->state);
781 goto again;
782
783 case AFS_CELL_ACTIVE:
784 if (atomic_read(&cell->active) > 1) {
785 if (test_and_clear_bit(AFS_CELL_FL_DO_LOOKUP, &cell->flags)) {
786 ret = afs_update_cell(cell);
787 if (ret < 0)
788 cell->error = ret;
789 }
790 goto done;
791 }
792 smp_store_release(&cell->state, AFS_CELL_DEACTIVATING);
793 wake_up_var(&cell->state);
794 goto again;
795
796 case AFS_CELL_DEACTIVATING:
797 if (atomic_read(&cell->active) > 1)
798 goto reverse_deactivation;
799 afs_deactivate_cell(net, cell);
800 smp_store_release(&cell->state, AFS_CELL_INACTIVE);
801 wake_up_var(&cell->state);
802 goto again;
803
804 case AFS_CELL_REMOVED:
805 goto done;
806
807 default:
808 break;
809 }
810 _debug("bad state %u", cell->state);
811 BUG();
812
813activation_failed:
814 cell->error = ret;
815 afs_deactivate_cell(net, cell);
816
817 smp_store_release(&cell->state, AFS_CELL_FAILED);
818 wake_up_var(&cell->state);
819 goto again;
820
821reverse_deactivation:
822 smp_store_release(&cell->state, AFS_CELL_ACTIVE);
823 wake_up_var(&cell->state);
824 _leave(" [deact->act]");
825 return;
826
827done:
828 _leave(" [done %u]", cell->state);
829 return;
830
831final_destruction:
832
833 afs_put_volume(cell->net, cell->root_volume, afs_volume_trace_put_cell_root);
834 cell->root_volume = NULL;
835 afs_put_cell(cell, afs_cell_trace_put_destroy);
836}
837
838static void afs_manage_cell_work(struct work_struct *work)
839{
840 struct afs_cell *cell = container_of(work, struct afs_cell, manager);
841
842 afs_manage_cell(cell);
843 afs_put_cell(cell, afs_cell_trace_put_queue_work);
844}
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859void afs_manage_cells(struct work_struct *work)
860{
861 struct afs_net *net = container_of(work, struct afs_net, cells_manager);
862 struct rb_node *cursor;
863 time64_t now = ktime_get_real_seconds(), next_manage = TIME64_MAX;
864 bool purging = !net->live;
865
866 _enter("");
867
868
869
870
871
872 down_read(&net->cells_lock);
873
874 for (cursor = rb_first(&net->cells); cursor; cursor = rb_next(cursor)) {
875 struct afs_cell *cell =
876 rb_entry(cursor, struct afs_cell, net_node);
877 unsigned active;
878 bool sched_cell = false;
879
880 active = atomic_read(&cell->active);
881 trace_afs_cell(cell->debug_id, atomic_read(&cell->ref),
882 active, afs_cell_trace_manage);
883
884 ASSERTCMP(active, >=, 1);
885
886 if (purging) {
887 if (test_and_clear_bit(AFS_CELL_FL_NO_GC, &cell->flags)) {
888 active = atomic_dec_return(&cell->active);
889 trace_afs_cell(cell->debug_id, atomic_read(&cell->ref),
890 active, afs_cell_trace_unuse_pin);
891 }
892 }
893
894 if (active == 1) {
895 struct afs_vlserver_list *vllist;
896 time64_t expire_at = cell->last_inactive;
897
898 read_lock(&cell->vl_servers_lock);
899 vllist = rcu_dereference_protected(
900 cell->vl_servers,
901 lockdep_is_held(&cell->vl_servers_lock));
902 if (vllist->nr_servers > 0)
903 expire_at += afs_cell_gc_delay;
904 read_unlock(&cell->vl_servers_lock);
905 if (purging || expire_at <= now)
906 sched_cell = true;
907 else if (expire_at < next_manage)
908 next_manage = expire_at;
909 }
910
911 if (!purging) {
912 if (test_bit(AFS_CELL_FL_DO_LOOKUP, &cell->flags))
913 sched_cell = true;
914 }
915
916 if (sched_cell)
917 afs_queue_cell(cell, afs_cell_trace_get_queue_manage);
918 }
919
920 up_read(&net->cells_lock);
921
922
923
924
925
926 if (!purging && next_manage < TIME64_MAX) {
927 now = ktime_get_real_seconds();
928
929 if (next_manage - now <= 0) {
930 if (queue_work(afs_wq, &net->cells_manager))
931 atomic_inc(&net->cells_outstanding);
932 } else {
933 afs_set_cell_timer(net, next_manage - now);
934 }
935 }
936
937 afs_dec_cells_outstanding(net);
938 _leave(" [%d]", atomic_read(&net->cells_outstanding));
939}
940
941
942
943
944void afs_cell_purge(struct afs_net *net)
945{
946 struct afs_cell *ws;
947
948 _enter("");
949
950 down_write(&net->cells_lock);
951 ws = net->ws_cell;
952 net->ws_cell = NULL;
953 up_write(&net->cells_lock);
954 afs_unuse_cell(net, ws, afs_cell_trace_unuse_ws);
955
956 _debug("del timer");
957 if (del_timer_sync(&net->cells_timer))
958 atomic_dec(&net->cells_outstanding);
959
960 _debug("kick mgr");
961 afs_queue_cell_manager(net);
962
963 _debug("wait");
964 wait_var_event(&net->cells_outstanding,
965 !atomic_read(&net->cells_outstanding));
966 _leave("");
967}
968