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-rw-r--r--fs/ocfs2/dlm/dlmdomain.c1469
1 files changed, 1469 insertions, 0 deletions
diff --git a/fs/ocfs2/dlm/dlmdomain.c b/fs/ocfs2/dlm/dlmdomain.c
new file mode 100644
index 000000000000..da3c22045f89
--- /dev/null
+++ b/fs/ocfs2/dlm/dlmdomain.c
@@ -0,0 +1,1469 @@
1/* -*- mode: c; c-basic-offset: 8; -*-
2 * vim: noexpandtab sw=8 ts=8 sts=0:
3 *
4 * dlmdomain.c
5 *
6 * defines domain join / leave apis
7 *
8 * Copyright (C) 2004 Oracle. All rights reserved.
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public
12 * License as published by the Free Software Foundation; either
13 * version 2 of the License, or (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public
21 * License along with this program; if not, write to the
22 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
23 * Boston, MA 021110-1307, USA.
24 *
25 */
26
27#include <linux/module.h>
28#include <linux/types.h>
29#include <linux/slab.h>
30#include <linux/highmem.h>
31#include <linux/utsname.h>
32#include <linux/init.h>
33#include <linux/spinlock.h>
34#include <linux/delay.h>
35#include <linux/err.h>
36
37#include "cluster/heartbeat.h"
38#include "cluster/nodemanager.h"
39#include "cluster/tcp.h"
40
41#include "dlmapi.h"
42#include "dlmcommon.h"
43
44#include "dlmdebug.h"
45#include "dlmdomain.h"
46
47#include "dlmver.h"
48
49#define MLOG_MASK_PREFIX (ML_DLM|ML_DLM_DOMAIN)
50#include "cluster/masklog.h"
51
52/*
53 *
54 * spinlock lock ordering: if multiple locks are needed, obey this ordering:
55 * dlm_domain_lock
56 * struct dlm_ctxt->spinlock
57 * struct dlm_lock_resource->spinlock
58 * struct dlm_ctxt->master_lock
59 * struct dlm_ctxt->ast_lock
60 * dlm_master_list_entry->spinlock
61 * dlm_lock->spinlock
62 *
63 */
64
65spinlock_t dlm_domain_lock = SPIN_LOCK_UNLOCKED;
66LIST_HEAD(dlm_domains);
67static DECLARE_WAIT_QUEUE_HEAD(dlm_domain_events);
68
69#define DLM_DOMAIN_BACKOFF_MS 200
70
71static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data);
72static int dlm_assert_joined_handler(struct o2net_msg *msg, u32 len, void *data);
73static int dlm_cancel_join_handler(struct o2net_msg *msg, u32 len, void *data);
74static int dlm_exit_domain_handler(struct o2net_msg *msg, u32 len, void *data);
75
76static void dlm_unregister_domain_handlers(struct dlm_ctxt *dlm);
77
78void __dlm_unhash_lockres(struct dlm_lock_resource *lockres)
79{
80 list_del_init(&lockres->list);
81 dlm_lockres_put(lockres);
82}
83
84void __dlm_insert_lockres(struct dlm_ctxt *dlm,
85 struct dlm_lock_resource *res)
86{
87 struct list_head *bucket;
88 struct qstr *q;
89
90 assert_spin_locked(&dlm->spinlock);
91
92 q = &res->lockname;
93 q->hash = full_name_hash(q->name, q->len);
94 bucket = &(dlm->resources[q->hash & DLM_HASH_MASK]);
95
96 /* get a reference for our hashtable */
97 dlm_lockres_get(res);
98
99 list_add_tail(&res->list, bucket);
100}
101
102struct dlm_lock_resource * __dlm_lookup_lockres(struct dlm_ctxt *dlm,
103 const char *name,
104 unsigned int len)
105{
106 unsigned int hash;
107 struct list_head *iter;
108 struct dlm_lock_resource *tmpres=NULL;
109 struct list_head *bucket;
110
111 mlog_entry("%.*s\n", len, name);
112
113 assert_spin_locked(&dlm->spinlock);
114
115 hash = full_name_hash(name, len);
116
117 bucket = &(dlm->resources[hash & DLM_HASH_MASK]);
118
119 /* check for pre-existing lock */
120 list_for_each(iter, bucket) {
121 tmpres = list_entry(iter, struct dlm_lock_resource, list);
122 if (tmpres->lockname.len == len &&
123 memcmp(tmpres->lockname.name, name, len) == 0) {
124 dlm_lockres_get(tmpres);
125 break;
126 }
127
128 tmpres = NULL;
129 }
130 return tmpres;
131}
132
133struct dlm_lock_resource * dlm_lookup_lockres(struct dlm_ctxt *dlm,
134 const char *name,
135 unsigned int len)
136{
137 struct dlm_lock_resource *res;
138
139 spin_lock(&dlm->spinlock);
140 res = __dlm_lookup_lockres(dlm, name, len);
141 spin_unlock(&dlm->spinlock);
142 return res;
143}
144
145static struct dlm_ctxt * __dlm_lookup_domain_full(const char *domain, int len)
146{
147 struct dlm_ctxt *tmp = NULL;
148 struct list_head *iter;
149
150 assert_spin_locked(&dlm_domain_lock);
151
152 /* tmp->name here is always NULL terminated,
153 * but domain may not be! */
154 list_for_each(iter, &dlm_domains) {
155 tmp = list_entry (iter, struct dlm_ctxt, list);
156 if (strlen(tmp->name) == len &&
157 memcmp(tmp->name, domain, len)==0)
158 break;
159 tmp = NULL;
160 }
161
162 return tmp;
163}
164
165/* For null terminated domain strings ONLY */
166static struct dlm_ctxt * __dlm_lookup_domain(const char *domain)
167{
168 assert_spin_locked(&dlm_domain_lock);
169
170 return __dlm_lookup_domain_full(domain, strlen(domain));
171}
172
173
174/* returns true on one of two conditions:
175 * 1) the domain does not exist
176 * 2) the domain exists and it's state is "joined" */
177static int dlm_wait_on_domain_helper(const char *domain)
178{
179 int ret = 0;
180 struct dlm_ctxt *tmp = NULL;
181
182 spin_lock(&dlm_domain_lock);
183
184 tmp = __dlm_lookup_domain(domain);
185 if (!tmp)
186 ret = 1;
187 else if (tmp->dlm_state == DLM_CTXT_JOINED)
188 ret = 1;
189
190 spin_unlock(&dlm_domain_lock);
191 return ret;
192}
193
194static void dlm_free_ctxt_mem(struct dlm_ctxt *dlm)
195{
196 if (dlm->resources)
197 free_page((unsigned long) dlm->resources);
198
199 if (dlm->name)
200 kfree(dlm->name);
201
202 kfree(dlm);
203}
204
205/* A little strange - this function will be called while holding
206 * dlm_domain_lock and is expected to be holding it on the way out. We
207 * will however drop and reacquire it multiple times */
208static void dlm_ctxt_release(struct kref *kref)
209{
210 struct dlm_ctxt *dlm;
211
212 dlm = container_of(kref, struct dlm_ctxt, dlm_refs);
213
214 BUG_ON(dlm->num_joins);
215 BUG_ON(dlm->dlm_state == DLM_CTXT_JOINED);
216
217 /* we may still be in the list if we hit an error during join. */
218 list_del_init(&dlm->list);
219
220 spin_unlock(&dlm_domain_lock);
221
222 mlog(0, "freeing memory from domain %s\n", dlm->name);
223
224 wake_up(&dlm_domain_events);
225
226 dlm_free_ctxt_mem(dlm);
227
228 spin_lock(&dlm_domain_lock);
229}
230
231void dlm_put(struct dlm_ctxt *dlm)
232{
233 spin_lock(&dlm_domain_lock);
234 kref_put(&dlm->dlm_refs, dlm_ctxt_release);
235 spin_unlock(&dlm_domain_lock);
236}
237
238static void __dlm_get(struct dlm_ctxt *dlm)
239{
240 kref_get(&dlm->dlm_refs);
241}
242
243/* given a questionable reference to a dlm object, gets a reference if
244 * it can find it in the list, otherwise returns NULL in which case
245 * you shouldn't trust your pointer. */
246struct dlm_ctxt *dlm_grab(struct dlm_ctxt *dlm)
247{
248 struct list_head *iter;
249 struct dlm_ctxt *target = NULL;
250
251 spin_lock(&dlm_domain_lock);
252
253 list_for_each(iter, &dlm_domains) {
254 target = list_entry (iter, struct dlm_ctxt, list);
255
256 if (target == dlm) {
257 __dlm_get(target);
258 break;
259 }
260
261 target = NULL;
262 }
263
264 spin_unlock(&dlm_domain_lock);
265
266 return target;
267}
268
269int dlm_domain_fully_joined(struct dlm_ctxt *dlm)
270{
271 int ret;
272
273 spin_lock(&dlm_domain_lock);
274 ret = (dlm->dlm_state == DLM_CTXT_JOINED) ||
275 (dlm->dlm_state == DLM_CTXT_IN_SHUTDOWN);
276 spin_unlock(&dlm_domain_lock);
277
278 return ret;
279}
280
281static void dlm_complete_dlm_shutdown(struct dlm_ctxt *dlm)
282{
283 dlm_unregister_domain_handlers(dlm);
284 dlm_complete_thread(dlm);
285 dlm_complete_recovery_thread(dlm);
286
287 /* We've left the domain. Now we can take ourselves out of the
288 * list and allow the kref stuff to help us free the
289 * memory. */
290 spin_lock(&dlm_domain_lock);
291 list_del_init(&dlm->list);
292 spin_unlock(&dlm_domain_lock);
293
294 /* Wake up anyone waiting for us to remove this domain */
295 wake_up(&dlm_domain_events);
296}
297
298static void dlm_migrate_all_locks(struct dlm_ctxt *dlm)
299{
300 int i;
301 struct dlm_lock_resource *res;
302
303 mlog(0, "Migrating locks from domain %s\n", dlm->name);
304restart:
305 spin_lock(&dlm->spinlock);
306 for (i=0; i<DLM_HASH_SIZE; i++) {
307 while (!list_empty(&dlm->resources[i])) {
308 res = list_entry(dlm->resources[i].next,
309 struct dlm_lock_resource, list);
310 /* need reference when manually grabbing lockres */
311 dlm_lockres_get(res);
312 /* this should unhash the lockres
313 * and exit with dlm->spinlock */
314 mlog(0, "purging res=%p\n", res);
315 if (dlm_lockres_is_dirty(dlm, res)) {
316 /* HACK! this should absolutely go.
317 * need to figure out why some empty
318 * lockreses are still marked dirty */
319 mlog(ML_ERROR, "lockres %.*s dirty!\n",
320 res->lockname.len, res->lockname.name);
321
322 spin_unlock(&dlm->spinlock);
323 dlm_kick_thread(dlm, res);
324 wait_event(dlm->ast_wq, !dlm_lockres_is_dirty(dlm, res));
325 dlm_lockres_put(res);
326 goto restart;
327 }
328 dlm_purge_lockres(dlm, res);
329 dlm_lockres_put(res);
330 }
331 }
332 spin_unlock(&dlm->spinlock);
333
334 mlog(0, "DONE Migrating locks from domain %s\n", dlm->name);
335}
336
337static int dlm_no_joining_node(struct dlm_ctxt *dlm)
338{
339 int ret;
340
341 spin_lock(&dlm->spinlock);
342 ret = dlm->joining_node == DLM_LOCK_RES_OWNER_UNKNOWN;
343 spin_unlock(&dlm->spinlock);
344
345 return ret;
346}
347
348static void dlm_mark_domain_leaving(struct dlm_ctxt *dlm)
349{
350 /* Yikes, a double spinlock! I need domain_lock for the dlm
351 * state and the dlm spinlock for join state... Sorry! */
352again:
353 spin_lock(&dlm_domain_lock);
354 spin_lock(&dlm->spinlock);
355
356 if (dlm->joining_node != DLM_LOCK_RES_OWNER_UNKNOWN) {
357 mlog(0, "Node %d is joining, we wait on it.\n",
358 dlm->joining_node);
359 spin_unlock(&dlm->spinlock);
360 spin_unlock(&dlm_domain_lock);
361
362 wait_event(dlm->dlm_join_events, dlm_no_joining_node(dlm));
363 goto again;
364 }
365
366 dlm->dlm_state = DLM_CTXT_LEAVING;
367 spin_unlock(&dlm->spinlock);
368 spin_unlock(&dlm_domain_lock);
369}
370
371static void __dlm_print_nodes(struct dlm_ctxt *dlm)
372{
373 int node = -1;
374
375 assert_spin_locked(&dlm->spinlock);
376
377 mlog(ML_NOTICE, "Nodes in my domain (\"%s\"):\n", dlm->name);
378
379 while ((node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES,
380 node + 1)) < O2NM_MAX_NODES) {
381 mlog(ML_NOTICE, " node %d\n", node);
382 }
383}
384
385static int dlm_exit_domain_handler(struct o2net_msg *msg, u32 len, void *data)
386{
387 struct dlm_ctxt *dlm = data;
388 unsigned int node;
389 struct dlm_exit_domain *exit_msg = (struct dlm_exit_domain *) msg->buf;
390
391 mlog_entry("%p %u %p", msg, len, data);
392
393 if (!dlm_grab(dlm))
394 return 0;
395
396 node = exit_msg->node_idx;
397
398 mlog(0, "Node %u leaves domain %s\n", node, dlm->name);
399
400 spin_lock(&dlm->spinlock);
401 clear_bit(node, dlm->domain_map);
402 __dlm_print_nodes(dlm);
403
404 /* notify anything attached to the heartbeat events */
405 dlm_hb_event_notify_attached(dlm, node, 0);
406
407 spin_unlock(&dlm->spinlock);
408
409 dlm_put(dlm);
410
411 return 0;
412}
413
414static int dlm_send_one_domain_exit(struct dlm_ctxt *dlm,
415 unsigned int node)
416{
417 int status;
418 struct dlm_exit_domain leave_msg;
419
420 mlog(0, "Asking node %u if we can leave the domain %s me = %u\n",
421 node, dlm->name, dlm->node_num);
422
423 memset(&leave_msg, 0, sizeof(leave_msg));
424 leave_msg.node_idx = dlm->node_num;
425
426 status = o2net_send_message(DLM_EXIT_DOMAIN_MSG, dlm->key,
427 &leave_msg, sizeof(leave_msg), node,
428 NULL);
429
430 mlog(0, "status return %d from o2net_send_message\n", status);
431
432 return status;
433}
434
435
436static void dlm_leave_domain(struct dlm_ctxt *dlm)
437{
438 int node, clear_node, status;
439
440 /* At this point we've migrated away all our locks and won't
441 * accept mastership of new ones. The dlm is responsible for
442 * almost nothing now. We make sure not to confuse any joining
443 * nodes and then commence shutdown procedure. */
444
445 spin_lock(&dlm->spinlock);
446 /* Clear ourselves from the domain map */
447 clear_bit(dlm->node_num, dlm->domain_map);
448 while ((node = find_next_bit(dlm->domain_map, O2NM_MAX_NODES,
449 0)) < O2NM_MAX_NODES) {
450 /* Drop the dlm spinlock. This is safe wrt the domain_map.
451 * -nodes cannot be added now as the
452 * query_join_handlers knows to respond with OK_NO_MAP
453 * -we catch the right network errors if a node is
454 * removed from the map while we're sending him the
455 * exit message. */
456 spin_unlock(&dlm->spinlock);
457
458 clear_node = 1;
459
460 status = dlm_send_one_domain_exit(dlm, node);
461 if (status < 0 &&
462 status != -ENOPROTOOPT &&
463 status != -ENOTCONN) {
464 mlog(ML_NOTICE, "Error %d sending domain exit message "
465 "to node %d\n", status, node);
466
467 /* Not sure what to do here but lets sleep for
468 * a bit in case this was a transient
469 * error... */
470 msleep(DLM_DOMAIN_BACKOFF_MS);
471 clear_node = 0;
472 }
473
474 spin_lock(&dlm->spinlock);
475 /* If we're not clearing the node bit then we intend
476 * to loop back around to try again. */
477 if (clear_node)
478 clear_bit(node, dlm->domain_map);
479 }
480 spin_unlock(&dlm->spinlock);
481}
482
483int dlm_joined(struct dlm_ctxt *dlm)
484{
485 int ret = 0;
486
487 spin_lock(&dlm_domain_lock);
488
489 if (dlm->dlm_state == DLM_CTXT_JOINED)
490 ret = 1;
491
492 spin_unlock(&dlm_domain_lock);
493
494 return ret;
495}
496
497int dlm_shutting_down(struct dlm_ctxt *dlm)
498{
499 int ret = 0;
500
501 spin_lock(&dlm_domain_lock);
502
503 if (dlm->dlm_state == DLM_CTXT_IN_SHUTDOWN)
504 ret = 1;
505
506 spin_unlock(&dlm_domain_lock);
507
508 return ret;
509}
510
511void dlm_unregister_domain(struct dlm_ctxt *dlm)
512{
513 int leave = 0;
514
515 spin_lock(&dlm_domain_lock);
516 BUG_ON(dlm->dlm_state != DLM_CTXT_JOINED);
517 BUG_ON(!dlm->num_joins);
518
519 dlm->num_joins--;
520 if (!dlm->num_joins) {
521 /* We mark it "in shutdown" now so new register
522 * requests wait until we've completely left the
523 * domain. Don't use DLM_CTXT_LEAVING yet as we still
524 * want new domain joins to communicate with us at
525 * least until we've completed migration of our
526 * resources. */
527 dlm->dlm_state = DLM_CTXT_IN_SHUTDOWN;
528 leave = 1;
529 }
530 spin_unlock(&dlm_domain_lock);
531
532 if (leave) {
533 mlog(0, "shutting down domain %s\n", dlm->name);
534
535 /* We changed dlm state, notify the thread */
536 dlm_kick_thread(dlm, NULL);
537
538 dlm_migrate_all_locks(dlm);
539 dlm_mark_domain_leaving(dlm);
540 dlm_leave_domain(dlm);
541 dlm_complete_dlm_shutdown(dlm);
542 }
543 dlm_put(dlm);
544}
545EXPORT_SYMBOL_GPL(dlm_unregister_domain);
546
547static int dlm_query_join_handler(struct o2net_msg *msg, u32 len, void *data)
548{
549 struct dlm_query_join_request *query;
550 enum dlm_query_join_response response;
551 struct dlm_ctxt *dlm = NULL;
552
553 query = (struct dlm_query_join_request *) msg->buf;
554
555 mlog(0, "node %u wants to join domain %s\n", query->node_idx,
556 query->domain);
557
558 /*
559 * If heartbeat doesn't consider the node live, tell it
560 * to back off and try again. This gives heartbeat a chance
561 * to catch up.
562 */
563 if (!o2hb_check_node_heartbeating(query->node_idx)) {
564 mlog(0, "node %u is not in our live map yet\n",
565 query->node_idx);
566
567 response = JOIN_DISALLOW;
568 goto respond;
569 }
570
571 response = JOIN_OK_NO_MAP;
572
573 spin_lock(&dlm_domain_lock);
574 dlm = __dlm_lookup_domain_full(query->domain, query->name_len);
575 /* Once the dlm ctxt is marked as leaving then we don't want
576 * to be put in someone's domain map. */
577 if (dlm && dlm->dlm_state != DLM_CTXT_LEAVING) {
578 spin_lock(&dlm->spinlock);
579
580 if (dlm->dlm_state == DLM_CTXT_NEW &&
581 dlm->joining_node == DLM_LOCK_RES_OWNER_UNKNOWN) {
582 /*If this is a brand new context and we
583 * haven't started our join process yet, then
584 * the other node won the race. */
585 response = JOIN_OK_NO_MAP;
586 } else if (dlm->joining_node != DLM_LOCK_RES_OWNER_UNKNOWN) {
587 /* Disallow parallel joins. */
588 response = JOIN_DISALLOW;
589 } else {
590 /* Alright we're fully a part of this domain
591 * so we keep some state as to who's joining
592 * and indicate to him that needs to be fixed
593 * up. */
594 response = JOIN_OK;
595 __dlm_set_joining_node(dlm, query->node_idx);
596 }
597
598 spin_unlock(&dlm->spinlock);
599 }
600 spin_unlock(&dlm_domain_lock);
601
602respond:
603 mlog(0, "We respond with %u\n", response);
604
605 return response;
606}
607
608static int dlm_assert_joined_handler(struct o2net_msg *msg, u32 len, void *data)
609{
610 struct dlm_assert_joined *assert;
611 struct dlm_ctxt *dlm = NULL;
612
613 assert = (struct dlm_assert_joined *) msg->buf;
614
615 mlog(0, "node %u asserts join on domain %s\n", assert->node_idx,
616 assert->domain);
617
618 spin_lock(&dlm_domain_lock);
619 dlm = __dlm_lookup_domain_full(assert->domain, assert->name_len);
620 /* XXX should we consider no dlm ctxt an error? */
621 if (dlm) {
622 spin_lock(&dlm->spinlock);
623
624 /* Alright, this node has officially joined our
625 * domain. Set him in the map and clean up our
626 * leftover join state. */
627 BUG_ON(dlm->joining_node != assert->node_idx);
628 set_bit(assert->node_idx, dlm->domain_map);
629 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
630
631 __dlm_print_nodes(dlm);
632
633 /* notify anything attached to the heartbeat events */
634 dlm_hb_event_notify_attached(dlm, assert->node_idx, 1);
635
636 spin_unlock(&dlm->spinlock);
637 }
638 spin_unlock(&dlm_domain_lock);
639
640 return 0;
641}
642
643static int dlm_cancel_join_handler(struct o2net_msg *msg, u32 len, void *data)
644{
645 struct dlm_cancel_join *cancel;
646 struct dlm_ctxt *dlm = NULL;
647
648 cancel = (struct dlm_cancel_join *) msg->buf;
649
650 mlog(0, "node %u cancels join on domain %s\n", cancel->node_idx,
651 cancel->domain);
652
653 spin_lock(&dlm_domain_lock);
654 dlm = __dlm_lookup_domain_full(cancel->domain, cancel->name_len);
655
656 if (dlm) {
657 spin_lock(&dlm->spinlock);
658
659 /* Yikes, this guy wants to cancel his join. No
660 * problem, we simply cleanup our join state. */
661 BUG_ON(dlm->joining_node != cancel->node_idx);
662 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
663
664 spin_unlock(&dlm->spinlock);
665 }
666 spin_unlock(&dlm_domain_lock);
667
668 return 0;
669}
670
671static int dlm_send_one_join_cancel(struct dlm_ctxt *dlm,
672 unsigned int node)
673{
674 int status;
675 struct dlm_cancel_join cancel_msg;
676
677 memset(&cancel_msg, 0, sizeof(cancel_msg));
678 cancel_msg.node_idx = dlm->node_num;
679 cancel_msg.name_len = strlen(dlm->name);
680 memcpy(cancel_msg.domain, dlm->name, cancel_msg.name_len);
681
682 status = o2net_send_message(DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY,
683 &cancel_msg, sizeof(cancel_msg), node,
684 NULL);
685 if (status < 0) {
686 mlog_errno(status);
687 goto bail;
688 }
689
690bail:
691 return status;
692}
693
694/* map_size should be in bytes. */
695static int dlm_send_join_cancels(struct dlm_ctxt *dlm,
696 unsigned long *node_map,
697 unsigned int map_size)
698{
699 int status, tmpstat;
700 unsigned int node;
701
702 if (map_size != (BITS_TO_LONGS(O2NM_MAX_NODES) *
703 sizeof(unsigned long))) {
704 mlog(ML_ERROR,
705 "map_size %u != BITS_TO_LONGS(O2NM_MAX_NODES) %u\n",
706 map_size, BITS_TO_LONGS(O2NM_MAX_NODES));
707 return -EINVAL;
708 }
709
710 status = 0;
711 node = -1;
712 while ((node = find_next_bit(node_map, O2NM_MAX_NODES,
713 node + 1)) < O2NM_MAX_NODES) {
714 if (node == dlm->node_num)
715 continue;
716
717 tmpstat = dlm_send_one_join_cancel(dlm, node);
718 if (tmpstat) {
719 mlog(ML_ERROR, "Error return %d cancelling join on "
720 "node %d\n", tmpstat, node);
721 if (!status)
722 status = tmpstat;
723 }
724 }
725
726 if (status)
727 mlog_errno(status);
728 return status;
729}
730
731static int dlm_request_join(struct dlm_ctxt *dlm,
732 int node,
733 enum dlm_query_join_response *response)
734{
735 int status, retval;
736 struct dlm_query_join_request join_msg;
737
738 mlog(0, "querying node %d\n", node);
739
740 memset(&join_msg, 0, sizeof(join_msg));
741 join_msg.node_idx = dlm->node_num;
742 join_msg.name_len = strlen(dlm->name);
743 memcpy(join_msg.domain, dlm->name, join_msg.name_len);
744
745 status = o2net_send_message(DLM_QUERY_JOIN_MSG, DLM_MOD_KEY, &join_msg,
746 sizeof(join_msg), node, &retval);
747 if (status < 0 && status != -ENOPROTOOPT) {
748 mlog_errno(status);
749 goto bail;
750 }
751
752 /* -ENOPROTOOPT from the net code means the other side isn't
753 listening for our message type -- that's fine, it means
754 his dlm isn't up, so we can consider him a 'yes' but not
755 joined into the domain. */
756 if (status == -ENOPROTOOPT) {
757 status = 0;
758 *response = JOIN_OK_NO_MAP;
759 } else if (retval == JOIN_DISALLOW ||
760 retval == JOIN_OK ||
761 retval == JOIN_OK_NO_MAP) {
762 *response = retval;
763 } else {
764 status = -EINVAL;
765 mlog(ML_ERROR, "invalid response %d from node %u\n", retval,
766 node);
767 }
768
769 mlog(0, "status %d, node %d response is %d\n", status, node,
770 *response);
771
772bail:
773 return status;
774}
775
776static int dlm_send_one_join_assert(struct dlm_ctxt *dlm,
777 unsigned int node)
778{
779 int status;
780 struct dlm_assert_joined assert_msg;
781
782 mlog(0, "Sending join assert to node %u\n", node);
783
784 memset(&assert_msg, 0, sizeof(assert_msg));
785 assert_msg.node_idx = dlm->node_num;
786 assert_msg.name_len = strlen(dlm->name);
787 memcpy(assert_msg.domain, dlm->name, assert_msg.name_len);
788
789 status = o2net_send_message(DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY,
790 &assert_msg, sizeof(assert_msg), node,
791 NULL);
792 if (status < 0)
793 mlog_errno(status);
794
795 return status;
796}
797
798static void dlm_send_join_asserts(struct dlm_ctxt *dlm,
799 unsigned long *node_map)
800{
801 int status, node, live;
802
803 status = 0;
804 node = -1;
805 while ((node = find_next_bit(node_map, O2NM_MAX_NODES,
806 node + 1)) < O2NM_MAX_NODES) {
807 if (node == dlm->node_num)
808 continue;
809
810 do {
811 /* It is very important that this message be
812 * received so we spin until either the node
813 * has died or it gets the message. */
814 status = dlm_send_one_join_assert(dlm, node);
815
816 spin_lock(&dlm->spinlock);
817 live = test_bit(node, dlm->live_nodes_map);
818 spin_unlock(&dlm->spinlock);
819
820 if (status) {
821 mlog(ML_ERROR, "Error return %d asserting "
822 "join on node %d\n", status, node);
823
824 /* give us some time between errors... */
825 if (live)
826 msleep(DLM_DOMAIN_BACKOFF_MS);
827 }
828 } while (status && live);
829 }
830}
831
832struct domain_join_ctxt {
833 unsigned long live_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
834 unsigned long yes_resp_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
835};
836
837static int dlm_should_restart_join(struct dlm_ctxt *dlm,
838 struct domain_join_ctxt *ctxt,
839 enum dlm_query_join_response response)
840{
841 int ret;
842
843 if (response == JOIN_DISALLOW) {
844 mlog(0, "Latest response of disallow -- should restart\n");
845 return 1;
846 }
847
848 spin_lock(&dlm->spinlock);
849 /* For now, we restart the process if the node maps have
850 * changed at all */
851 ret = memcmp(ctxt->live_map, dlm->live_nodes_map,
852 sizeof(dlm->live_nodes_map));
853 spin_unlock(&dlm->spinlock);
854
855 if (ret)
856 mlog(0, "Node maps changed -- should restart\n");
857
858 return ret;
859}
860
861static int dlm_try_to_join_domain(struct dlm_ctxt *dlm)
862{
863 int status = 0, tmpstat, node;
864 struct domain_join_ctxt *ctxt;
865 enum dlm_query_join_response response;
866
867 mlog_entry("%p", dlm);
868
869 ctxt = kcalloc(1, sizeof(*ctxt), GFP_KERNEL);
870 if (!ctxt) {
871 status = -ENOMEM;
872 mlog_errno(status);
873 goto bail;
874 }
875
876 /* group sem locking should work for us here -- we're already
877 * registered for heartbeat events so filling this should be
878 * atomic wrt getting those handlers called. */
879 o2hb_fill_node_map(dlm->live_nodes_map, sizeof(dlm->live_nodes_map));
880
881 spin_lock(&dlm->spinlock);
882 memcpy(ctxt->live_map, dlm->live_nodes_map, sizeof(ctxt->live_map));
883
884 __dlm_set_joining_node(dlm, dlm->node_num);
885
886 spin_unlock(&dlm->spinlock);
887
888 node = -1;
889 while ((node = find_next_bit(ctxt->live_map, O2NM_MAX_NODES,
890 node + 1)) < O2NM_MAX_NODES) {
891 if (node == dlm->node_num)
892 continue;
893
894 status = dlm_request_join(dlm, node, &response);
895 if (status < 0) {
896 mlog_errno(status);
897 goto bail;
898 }
899
900 /* Ok, either we got a response or the node doesn't have a
901 * dlm up. */
902 if (response == JOIN_OK)
903 set_bit(node, ctxt->yes_resp_map);
904
905 if (dlm_should_restart_join(dlm, ctxt, response)) {
906 status = -EAGAIN;
907 goto bail;
908 }
909 }
910
911 mlog(0, "Yay, done querying nodes!\n");
912
913 /* Yay, everyone agree's we can join the domain. My domain is
914 * comprised of all nodes who were put in the
915 * yes_resp_map. Copy that into our domain map and send a join
916 * assert message to clean up everyone elses state. */
917 spin_lock(&dlm->spinlock);
918 memcpy(dlm->domain_map, ctxt->yes_resp_map,
919 sizeof(ctxt->yes_resp_map));
920 set_bit(dlm->node_num, dlm->domain_map);
921 spin_unlock(&dlm->spinlock);
922
923 dlm_send_join_asserts(dlm, ctxt->yes_resp_map);
924
925 /* Joined state *must* be set before the joining node
926 * information, otherwise the query_join handler may read no
927 * current joiner but a state of NEW and tell joining nodes
928 * we're not in the domain. */
929 spin_lock(&dlm_domain_lock);
930 dlm->dlm_state = DLM_CTXT_JOINED;
931 dlm->num_joins++;
932 spin_unlock(&dlm_domain_lock);
933
934bail:
935 spin_lock(&dlm->spinlock);
936 __dlm_set_joining_node(dlm, DLM_LOCK_RES_OWNER_UNKNOWN);
937 if (!status)
938 __dlm_print_nodes(dlm);
939 spin_unlock(&dlm->spinlock);
940
941 if (ctxt) {
942 /* Do we need to send a cancel message to any nodes? */
943 if (status < 0) {
944 tmpstat = dlm_send_join_cancels(dlm,
945 ctxt->yes_resp_map,
946 sizeof(ctxt->yes_resp_map));
947 if (tmpstat < 0)
948 mlog_errno(tmpstat);
949 }
950 kfree(ctxt);
951 }
952
953 mlog(0, "returning %d\n", status);
954 return status;
955}
956
957static void dlm_unregister_domain_handlers(struct dlm_ctxt *dlm)
958{
959 o2hb_unregister_callback(&dlm->dlm_hb_up);
960 o2hb_unregister_callback(&dlm->dlm_hb_down);
961 o2net_unregister_handler_list(&dlm->dlm_domain_handlers);
962}
963
964static int dlm_register_domain_handlers(struct dlm_ctxt *dlm)
965{
966 int status;
967
968 mlog(0, "registering handlers.\n");
969
970 o2hb_setup_callback(&dlm->dlm_hb_down, O2HB_NODE_DOWN_CB,
971 dlm_hb_node_down_cb, dlm, DLM_HB_NODE_DOWN_PRI);
972 status = o2hb_register_callback(&dlm->dlm_hb_down);
973 if (status)
974 goto bail;
975
976 o2hb_setup_callback(&dlm->dlm_hb_up, O2HB_NODE_UP_CB,
977 dlm_hb_node_up_cb, dlm, DLM_HB_NODE_UP_PRI);
978 status = o2hb_register_callback(&dlm->dlm_hb_up);
979 if (status)
980 goto bail;
981
982 status = o2net_register_handler(DLM_MASTER_REQUEST_MSG, dlm->key,
983 sizeof(struct dlm_master_request),
984 dlm_master_request_handler,
985 dlm, &dlm->dlm_domain_handlers);
986 if (status)
987 goto bail;
988
989 status = o2net_register_handler(DLM_ASSERT_MASTER_MSG, dlm->key,
990 sizeof(struct dlm_assert_master),
991 dlm_assert_master_handler,
992 dlm, &dlm->dlm_domain_handlers);
993 if (status)
994 goto bail;
995
996 status = o2net_register_handler(DLM_CREATE_LOCK_MSG, dlm->key,
997 sizeof(struct dlm_create_lock),
998 dlm_create_lock_handler,
999 dlm, &dlm->dlm_domain_handlers);
1000 if (status)
1001 goto bail;
1002
1003 status = o2net_register_handler(DLM_CONVERT_LOCK_MSG, dlm->key,
1004 DLM_CONVERT_LOCK_MAX_LEN,
1005 dlm_convert_lock_handler,
1006 dlm, &dlm->dlm_domain_handlers);
1007 if (status)
1008 goto bail;
1009
1010 status = o2net_register_handler(DLM_UNLOCK_LOCK_MSG, dlm->key,
1011 DLM_UNLOCK_LOCK_MAX_LEN,
1012 dlm_unlock_lock_handler,
1013 dlm, &dlm->dlm_domain_handlers);
1014 if (status)
1015 goto bail;
1016
1017 status = o2net_register_handler(DLM_PROXY_AST_MSG, dlm->key,
1018 DLM_PROXY_AST_MAX_LEN,
1019 dlm_proxy_ast_handler,
1020 dlm, &dlm->dlm_domain_handlers);
1021 if (status)
1022 goto bail;
1023
1024 status = o2net_register_handler(DLM_EXIT_DOMAIN_MSG, dlm->key,
1025 sizeof(struct dlm_exit_domain),
1026 dlm_exit_domain_handler,
1027 dlm, &dlm->dlm_domain_handlers);
1028 if (status)
1029 goto bail;
1030
1031 status = o2net_register_handler(DLM_MIGRATE_REQUEST_MSG, dlm->key,
1032 sizeof(struct dlm_migrate_request),
1033 dlm_migrate_request_handler,
1034 dlm, &dlm->dlm_domain_handlers);
1035 if (status)
1036 goto bail;
1037
1038 status = o2net_register_handler(DLM_MIG_LOCKRES_MSG, dlm->key,
1039 DLM_MIG_LOCKRES_MAX_LEN,
1040 dlm_mig_lockres_handler,
1041 dlm, &dlm->dlm_domain_handlers);
1042 if (status)
1043 goto bail;
1044
1045 status = o2net_register_handler(DLM_MASTER_REQUERY_MSG, dlm->key,
1046 sizeof(struct dlm_master_requery),
1047 dlm_master_requery_handler,
1048 dlm, &dlm->dlm_domain_handlers);
1049 if (status)
1050 goto bail;
1051
1052 status = o2net_register_handler(DLM_LOCK_REQUEST_MSG, dlm->key,
1053 sizeof(struct dlm_lock_request),
1054 dlm_request_all_locks_handler,
1055 dlm, &dlm->dlm_domain_handlers);
1056 if (status)
1057 goto bail;
1058
1059 status = o2net_register_handler(DLM_RECO_DATA_DONE_MSG, dlm->key,
1060 sizeof(struct dlm_reco_data_done),
1061 dlm_reco_data_done_handler,
1062 dlm, &dlm->dlm_domain_handlers);
1063 if (status)
1064 goto bail;
1065
1066 status = o2net_register_handler(DLM_BEGIN_RECO_MSG, dlm->key,
1067 sizeof(struct dlm_begin_reco),
1068 dlm_begin_reco_handler,
1069 dlm, &dlm->dlm_domain_handlers);
1070 if (status)
1071 goto bail;
1072
1073 status = o2net_register_handler(DLM_FINALIZE_RECO_MSG, dlm->key,
1074 sizeof(struct dlm_finalize_reco),
1075 dlm_finalize_reco_handler,
1076 dlm, &dlm->dlm_domain_handlers);
1077 if (status)
1078 goto bail;
1079
1080bail:
1081 if (status)
1082 dlm_unregister_domain_handlers(dlm);
1083
1084 return status;
1085}
1086
1087static int dlm_join_domain(struct dlm_ctxt *dlm)
1088{
1089 int status;
1090
1091 BUG_ON(!dlm);
1092
1093 mlog(0, "Join domain %s\n", dlm->name);
1094
1095 status = dlm_register_domain_handlers(dlm);
1096 if (status) {
1097 mlog_errno(status);
1098 goto bail;
1099 }
1100
1101 status = dlm_launch_thread(dlm);
1102 if (status < 0) {
1103 mlog_errno(status);
1104 goto bail;
1105 }
1106
1107 status = dlm_launch_recovery_thread(dlm);
1108 if (status < 0) {
1109 mlog_errno(status);
1110 goto bail;
1111 }
1112
1113 do {
1114 unsigned int backoff;
1115 status = dlm_try_to_join_domain(dlm);
1116
1117 /* If we're racing another node to the join, then we
1118 * need to back off temporarily and let them
1119 * complete. */
1120 if (status == -EAGAIN) {
1121 if (signal_pending(current)) {
1122 status = -ERESTARTSYS;
1123 goto bail;
1124 }
1125
1126 /*
1127 * <chip> After you!
1128 * <dale> No, after you!
1129 * <chip> I insist!
1130 * <dale> But you first!
1131 * ...
1132 */
1133 backoff = (unsigned int)(jiffies & 0x3);
1134 backoff *= DLM_DOMAIN_BACKOFF_MS;
1135 mlog(0, "backoff %d\n", backoff);
1136 msleep(backoff);
1137 }
1138 } while (status == -EAGAIN);
1139
1140 if (status < 0) {
1141 mlog_errno(status);
1142 goto bail;
1143 }
1144
1145 status = 0;
1146bail:
1147 wake_up(&dlm_domain_events);
1148
1149 if (status) {
1150 dlm_unregister_domain_handlers(dlm);
1151 dlm_complete_thread(dlm);
1152 dlm_complete_recovery_thread(dlm);
1153 }
1154
1155 return status;
1156}
1157
1158static struct dlm_ctxt *dlm_alloc_ctxt(const char *domain,
1159 u32 key)
1160{
1161 int i;
1162 struct dlm_ctxt *dlm = NULL;
1163
1164 dlm = kcalloc(1, sizeof(*dlm), GFP_KERNEL);
1165 if (!dlm) {
1166 mlog_errno(-ENOMEM);
1167 goto leave;
1168 }
1169
1170 dlm->name = kmalloc(strlen(domain) + 1, GFP_KERNEL);
1171 if (dlm->name == NULL) {
1172 mlog_errno(-ENOMEM);
1173 kfree(dlm);
1174 dlm = NULL;
1175 goto leave;
1176 }
1177
1178 dlm->resources = (struct list_head *) __get_free_page(GFP_KERNEL);
1179 if (!dlm->resources) {
1180 mlog_errno(-ENOMEM);
1181 kfree(dlm->name);
1182 kfree(dlm);
1183 dlm = NULL;
1184 goto leave;
1185 }
1186 memset(dlm->resources, 0, PAGE_SIZE);
1187
1188 for (i=0; i<DLM_HASH_SIZE; i++)
1189 INIT_LIST_HEAD(&dlm->resources[i]);
1190
1191 strcpy(dlm->name, domain);
1192 dlm->key = key;
1193 dlm->node_num = o2nm_this_node();
1194
1195 spin_lock_init(&dlm->spinlock);
1196 spin_lock_init(&dlm->master_lock);
1197 spin_lock_init(&dlm->ast_lock);
1198 INIT_LIST_HEAD(&dlm->list);
1199 INIT_LIST_HEAD(&dlm->dirty_list);
1200 INIT_LIST_HEAD(&dlm->reco.resources);
1201 INIT_LIST_HEAD(&dlm->reco.received);
1202 INIT_LIST_HEAD(&dlm->reco.node_data);
1203 INIT_LIST_HEAD(&dlm->purge_list);
1204 INIT_LIST_HEAD(&dlm->dlm_domain_handlers);
1205 dlm->reco.state = 0;
1206
1207 INIT_LIST_HEAD(&dlm->pending_asts);
1208 INIT_LIST_HEAD(&dlm->pending_basts);
1209
1210 mlog(0, "dlm->recovery_map=%p, &(dlm->recovery_map[0])=%p\n",
1211 dlm->recovery_map, &(dlm->recovery_map[0]));
1212
1213 memset(dlm->recovery_map, 0, sizeof(dlm->recovery_map));
1214 memset(dlm->live_nodes_map, 0, sizeof(dlm->live_nodes_map));
1215 memset(dlm->domain_map, 0, sizeof(dlm->domain_map));
1216
1217 dlm->dlm_thread_task = NULL;
1218 dlm->dlm_reco_thread_task = NULL;
1219 init_waitqueue_head(&dlm->dlm_thread_wq);
1220 init_waitqueue_head(&dlm->dlm_reco_thread_wq);
1221 init_waitqueue_head(&dlm->reco.event);
1222 init_waitqueue_head(&dlm->ast_wq);
1223 init_waitqueue_head(&dlm->migration_wq);
1224 INIT_LIST_HEAD(&dlm->master_list);
1225 INIT_LIST_HEAD(&dlm->mle_hb_events);
1226
1227 dlm->joining_node = DLM_LOCK_RES_OWNER_UNKNOWN;
1228 init_waitqueue_head(&dlm->dlm_join_events);
1229
1230 dlm->reco.new_master = O2NM_INVALID_NODE_NUM;
1231 dlm->reco.dead_node = O2NM_INVALID_NODE_NUM;
1232 atomic_set(&dlm->local_resources, 0);
1233 atomic_set(&dlm->remote_resources, 0);
1234 atomic_set(&dlm->unknown_resources, 0);
1235
1236 spin_lock_init(&dlm->work_lock);
1237 INIT_LIST_HEAD(&dlm->work_list);
1238 INIT_WORK(&dlm->dispatched_work, dlm_dispatch_work, dlm);
1239
1240 kref_init(&dlm->dlm_refs);
1241 dlm->dlm_state = DLM_CTXT_NEW;
1242
1243 INIT_LIST_HEAD(&dlm->dlm_eviction_callbacks);
1244
1245 mlog(0, "context init: refcount %u\n",
1246 atomic_read(&dlm->dlm_refs.refcount));
1247
1248leave:
1249 return dlm;
1250}
1251
1252/*
1253 * dlm_register_domain: one-time setup per "domain"
1254 */
1255struct dlm_ctxt * dlm_register_domain(const char *domain,
1256 u32 key)
1257{
1258 int ret;
1259 struct dlm_ctxt *dlm = NULL;
1260 struct dlm_ctxt *new_ctxt = NULL;
1261
1262 if (strlen(domain) > O2NM_MAX_NAME_LEN) {
1263 ret = -ENAMETOOLONG;
1264 mlog(ML_ERROR, "domain name length too long\n");
1265 goto leave;
1266 }
1267
1268 if (!o2hb_check_local_node_heartbeating()) {
1269 mlog(ML_ERROR, "the local node has not been configured, or is "
1270 "not heartbeating\n");
1271 ret = -EPROTO;
1272 goto leave;
1273 }
1274
1275 mlog(0, "register called for domain \"%s\"\n", domain);
1276
1277retry:
1278 dlm = NULL;
1279 if (signal_pending(current)) {
1280 ret = -ERESTARTSYS;
1281 mlog_errno(ret);
1282 goto leave;
1283 }
1284
1285 spin_lock(&dlm_domain_lock);
1286
1287 dlm = __dlm_lookup_domain(domain);
1288 if (dlm) {
1289 if (dlm->dlm_state != DLM_CTXT_JOINED) {
1290 spin_unlock(&dlm_domain_lock);
1291
1292 mlog(0, "This ctxt is not joined yet!\n");
1293 wait_event_interruptible(dlm_domain_events,
1294 dlm_wait_on_domain_helper(
1295 domain));
1296 goto retry;
1297 }
1298
1299 __dlm_get(dlm);
1300 dlm->num_joins++;
1301
1302 spin_unlock(&dlm_domain_lock);
1303
1304 ret = 0;
1305 goto leave;
1306 }
1307
1308 /* doesn't exist */
1309 if (!new_ctxt) {
1310 spin_unlock(&dlm_domain_lock);
1311
1312 new_ctxt = dlm_alloc_ctxt(domain, key);
1313 if (new_ctxt)
1314 goto retry;
1315
1316 ret = -ENOMEM;
1317 mlog_errno(ret);
1318 goto leave;
1319 }
1320
1321 /* a little variable switch-a-roo here... */
1322 dlm = new_ctxt;
1323 new_ctxt = NULL;
1324
1325 /* add the new domain */
1326 list_add_tail(&dlm->list, &dlm_domains);
1327 spin_unlock(&dlm_domain_lock);
1328
1329 ret = dlm_join_domain(dlm);
1330 if (ret) {
1331 mlog_errno(ret);
1332 dlm_put(dlm);
1333 goto leave;
1334 }
1335
1336 ret = 0;
1337leave:
1338 if (new_ctxt)
1339 dlm_free_ctxt_mem(new_ctxt);
1340
1341 if (ret < 0)
1342 dlm = ERR_PTR(ret);
1343
1344 return dlm;
1345}
1346EXPORT_SYMBOL_GPL(dlm_register_domain);
1347
1348static LIST_HEAD(dlm_join_handlers);
1349
1350static void dlm_unregister_net_handlers(void)
1351{
1352 o2net_unregister_handler_list(&dlm_join_handlers);
1353}
1354
1355static int dlm_register_net_handlers(void)
1356{
1357 int status = 0;
1358
1359 status = o2net_register_handler(DLM_QUERY_JOIN_MSG, DLM_MOD_KEY,
1360 sizeof(struct dlm_query_join_request),
1361 dlm_query_join_handler,
1362 NULL, &dlm_join_handlers);
1363 if (status)
1364 goto bail;
1365
1366 status = o2net_register_handler(DLM_ASSERT_JOINED_MSG, DLM_MOD_KEY,
1367 sizeof(struct dlm_assert_joined),
1368 dlm_assert_joined_handler,
1369 NULL, &dlm_join_handlers);
1370 if (status)
1371 goto bail;
1372
1373 status = o2net_register_handler(DLM_CANCEL_JOIN_MSG, DLM_MOD_KEY,
1374 sizeof(struct dlm_cancel_join),
1375 dlm_cancel_join_handler,
1376 NULL, &dlm_join_handlers);
1377
1378bail:
1379 if (status < 0)
1380 dlm_unregister_net_handlers();
1381
1382 return status;
1383}
1384
1385/* Domain eviction callback handling.
1386 *
1387 * The file system requires notification of node death *before* the
1388 * dlm completes it's recovery work, otherwise it may be able to
1389 * acquire locks on resources requiring recovery. Since the dlm can
1390 * evict a node from it's domain *before* heartbeat fires, a similar
1391 * mechanism is required. */
1392
1393/* Eviction is not expected to happen often, so a per-domain lock is
1394 * not necessary. Eviction callbacks are allowed to sleep for short
1395 * periods of time. */
1396static DECLARE_RWSEM(dlm_callback_sem);
1397
1398void dlm_fire_domain_eviction_callbacks(struct dlm_ctxt *dlm,
1399 int node_num)
1400{
1401 struct list_head *iter;
1402 struct dlm_eviction_cb *cb;
1403
1404 down_read(&dlm_callback_sem);
1405 list_for_each(iter, &dlm->dlm_eviction_callbacks) {
1406 cb = list_entry(iter, struct dlm_eviction_cb, ec_item);
1407
1408 cb->ec_func(node_num, cb->ec_data);
1409 }
1410 up_read(&dlm_callback_sem);
1411}
1412
1413void dlm_setup_eviction_cb(struct dlm_eviction_cb *cb,
1414 dlm_eviction_func *f,
1415 void *data)
1416{
1417 INIT_LIST_HEAD(&cb->ec_item);
1418 cb->ec_func = f;
1419 cb->ec_data = data;
1420}
1421EXPORT_SYMBOL_GPL(dlm_setup_eviction_cb);
1422
1423void dlm_register_eviction_cb(struct dlm_ctxt *dlm,
1424 struct dlm_eviction_cb *cb)
1425{
1426 down_write(&dlm_callback_sem);
1427 list_add_tail(&cb->ec_item, &dlm->dlm_eviction_callbacks);
1428 up_write(&dlm_callback_sem);
1429}
1430EXPORT_SYMBOL_GPL(dlm_register_eviction_cb);
1431
1432void dlm_unregister_eviction_cb(struct dlm_eviction_cb *cb)
1433{
1434 down_write(&dlm_callback_sem);
1435 list_del_init(&cb->ec_item);
1436 up_write(&dlm_callback_sem);
1437}
1438EXPORT_SYMBOL_GPL(dlm_unregister_eviction_cb);
1439
1440static int __init dlm_init(void)
1441{
1442 int status;
1443
1444 dlm_print_version();
1445
1446 status = dlm_init_mle_cache();
1447 if (status)
1448 return -1;
1449
1450 status = dlm_register_net_handlers();
1451 if (status) {
1452 dlm_destroy_mle_cache();
1453 return -1;
1454 }
1455
1456 return 0;
1457}
1458
1459static void __exit dlm_exit (void)
1460{
1461 dlm_unregister_net_handlers();
1462 dlm_destroy_mle_cache();
1463}
1464
1465MODULE_AUTHOR("Oracle");
1466MODULE_LICENSE("GPL");
1467
1468module_init(dlm_init);
1469module_exit(dlm_exit);
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-24 10:17:32 -0500