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membarrier: clean up selftest
[linux-2.6-block.git] / fs / ocfs2 / dlm / dlmmaster.c
CommitLineData
6714d8e8
KH		 1/* -*- mode: c; c-basic-offset: 8; -*-
2 * vim: noexpandtab sw=8 ts=8 sts=0:
3 *
4 * dlmmod.c
5 *
6 * standalone DLM module
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
28#include <linux/module.h>
29#include <linux/fs.h>
30#include <linux/types.h>
31#include <linux/slab.h>
32#include <linux/highmem.h>
6714d8e8
KH		 33#include <linux/init.h>
34#include <linux/sysctl.h>
35#include <linux/random.h>
36#include <linux/blkdev.h>
37#include <linux/socket.h>
38#include <linux/inet.h>
39#include <linux/spinlock.h>
40#include <linux/delay.h>
41
42
43#include "cluster/heartbeat.h"
44#include "cluster/nodemanager.h"
45#include "cluster/tcp.h"
46
47#include "dlmapi.h"
48#include "dlmcommon.h"
82353b59 49#include "dlmdomain.h"
e5a0334c 50#include "dlmdebug.h"
6714d8e8
KH		 51
52#define MLOG_MASK_PREFIX (ML_DLM|ML_DLM_MASTER)
53#include "cluster/masklog.h"
54
6714d8e8
KH		 55static void dlm_mle_node_down(struct dlm_ctxt *dlm,
56 struct dlm_master_list_entry *mle,
57 struct o2nm_node *node,
58 int idx);
59static void dlm_mle_node_up(struct dlm_ctxt *dlm,
60 struct dlm_master_list_entry *mle,
61 struct o2nm_node *node,
62 int idx);
63
64static void dlm_assert_master_worker(struct dlm_work_item *item, void *data);
ba2bf218
KH		 65static int dlm_do_assert_master(struct dlm_ctxt *dlm,
66 struct dlm_lock_resource *res,
67 void *nodemap, u32 flags);
f3f85464 68static void dlm_deref_lockres_worker(struct dlm_work_item *item, void *data);
6714d8e8
KH		 69
70static inline int dlm_mle_equal(struct dlm_ctxt *dlm,
71 struct dlm_master_list_entry *mle,
72 const char *name,
73 unsigned int namelen)
74{
6714d8e8
KH		 75 if (dlm != mle->dlm)
76 return 0;
77
7141514b
SM		 78 if (namelen != mle->mnamelen ||
79 memcmp(name, mle->mname, namelen) != 0)
f77a9a78
SM		 80 return 0;
81
6714d8e8
KH		 82 return 1;
83}
84
1a5c4e2a
FF		 85static struct kmem_cache *dlm_lockres_cache;
86static struct kmem_cache *dlm_lockname_cache;
87static struct kmem_cache *dlm_mle_cache;
6714d8e8 88
6714d8e8
KH		 89static void dlm_mle_release(struct kref *kref);
90static void dlm_init_mle(struct dlm_master_list_entry *mle,
91 enum dlm_mle_type type,
92 struct dlm_ctxt *dlm,
93 struct dlm_lock_resource *res,
94 const char *name,
95 unsigned int namelen);
96static void dlm_put_mle(struct dlm_master_list_entry *mle);
97static void __dlm_put_mle(struct dlm_master_list_entry *mle);
98static int dlm_find_mle(struct dlm_ctxt *dlm,
99 struct dlm_master_list_entry **mle,
100 char *name, unsigned int namelen);
101
ba2bf218
KH		 102static int dlm_do_master_request(struct dlm_lock_resource *res,
103 struct dlm_master_list_entry *mle, int to);
6714d8e8
KH		 104
105
106static int dlm_wait_for_lock_mastery(struct dlm_ctxt *dlm,
107 struct dlm_lock_resource *res,
108 struct dlm_master_list_entry *mle,
109 int *blocked);
110static int dlm_restart_lock_mastery(struct dlm_ctxt *dlm,
111 struct dlm_lock_resource *res,
112 struct dlm_master_list_entry *mle,
113 int blocked);
114static int dlm_add_migration_mle(struct dlm_ctxt *dlm,
115 struct dlm_lock_resource *res,
116 struct dlm_master_list_entry *mle,
117 struct dlm_master_list_entry **oldmle,
118 const char *name, unsigned int namelen,
119 u8 new_master, u8 master);
120
121static u8 dlm_pick_migration_target(struct dlm_ctxt *dlm,
122 struct dlm_lock_resource *res);
123static void dlm_remove_nonlocal_locks(struct dlm_ctxt *dlm,
124 struct dlm_lock_resource *res);
125static int dlm_mark_lockres_migrating(struct dlm_ctxt *dlm,
126 struct dlm_lock_resource *res,
127 u8 target);
c03872f5
KH		 128static int dlm_pre_master_reco_lockres(struct dlm_ctxt *dlm,
129 struct dlm_lock_resource *res);
6714d8e8
KH		 130
131
132int dlm_is_host_down(int errno)
133{
134 switch (errno) {
135 case -EBADF:
136 case -ECONNREFUSED:
137 case -ENOTCONN:
138 case -ECONNRESET:
139 case -EPIPE:
140 case -EHOSTDOWN:
141 case -EHOSTUNREACH:
142 case -ETIMEDOUT:
143 case -ECONNABORTED:
144 case -ENETDOWN:
145 case -ENETUNREACH:
146 case -ENETRESET:
147 case -ESHUTDOWN:
148 case -ENOPROTOOPT:
149 case -EINVAL: /* if returned from our tcp code,
150 this means there is no socket */
151 return 1;
152 }
153 return 0;
154}
155
156
157/*
158 * MASTER LIST FUNCTIONS
159 */
160
161
162/*
163 * regarding master list entries and heartbeat callbacks:
164 *
165 * in order to avoid sleeping and allocation that occurs in
166 * heartbeat, master list entries are simply attached to the
167 * dlm's established heartbeat callbacks. the mle is attached
168 * when it is created, and since the dlm->spinlock is held at
169 * that time, any heartbeat event will be properly discovered
170 * by the mle. the mle needs to be detached from the
171 * dlm->mle_hb_events list as soon as heartbeat events are no
172 * longer useful to the mle, and before the mle is freed.
173 *
174 * as a general rule, heartbeat events are no longer needed by
175 * the mle once an "answer" regarding the lock master has been
176 * received.
177 */
178static inline void __dlm_mle_attach_hb_events(struct dlm_ctxt *dlm,
179 struct dlm_master_list_entry *mle)
180{
181 assert_spin_locked(&dlm->spinlock);
182
183 list_add_tail(&mle->hb_events, &dlm->mle_hb_events);
184}
185
186
187static inline void __dlm_mle_detach_hb_events(struct dlm_ctxt *dlm,
188 struct dlm_master_list_entry *mle)
189{
190 if (!list_empty(&mle->hb_events))
191 list_del_init(&mle->hb_events);
192}
193
194
195static inline void dlm_mle_detach_hb_events(struct dlm_ctxt *dlm,
196 struct dlm_master_list_entry *mle)
197{
198 spin_lock(&dlm->spinlock);
199 __dlm_mle_detach_hb_events(dlm, mle);
200 spin_unlock(&dlm->spinlock);
201}
202
a2bf0477
KH		 203static void dlm_get_mle_inuse(struct dlm_master_list_entry *mle)
204{
205 struct dlm_ctxt *dlm;
206 dlm = mle->dlm;
207
208 assert_spin_locked(&dlm->spinlock);
209 assert_spin_locked(&dlm->master_lock);
210 mle->inuse++;
211 kref_get(&mle->mle_refs);
212}
213
214static void dlm_put_mle_inuse(struct dlm_master_list_entry *mle)
215{
216 struct dlm_ctxt *dlm;
217 dlm = mle->dlm;
218
219 spin_lock(&dlm->spinlock);
220 spin_lock(&dlm->master_lock);
221 mle->inuse--;
222 __dlm_put_mle(mle);
223 spin_unlock(&dlm->master_lock);
224 spin_unlock(&dlm->spinlock);
225
226}
227
6714d8e8
KH		 228/* remove from list and free */
229static void __dlm_put_mle(struct dlm_master_list_entry *mle)
230{
231 struct dlm_ctxt *dlm;
232 dlm = mle->dlm;
233
234 assert_spin_locked(&dlm->spinlock);
235 assert_spin_locked(&dlm->master_lock);
aa852354
KH		 236 if (!atomic_read(&mle->mle_refs.refcount)) {
237 /* this may or may not crash, but who cares.
238 * it's a BUG. */
239 mlog(ML_ERROR, "bad mle: %p\n", mle);
240 dlm_print_one_mle(mle);
241 BUG();
242 } else
243 kref_put(&mle->mle_refs, dlm_mle_release);
6714d8e8
KH		 244}
245
246
247/* must not have any spinlocks coming in */
248static void dlm_put_mle(struct dlm_master_list_entry *mle)
249{
250 struct dlm_ctxt *dlm;
251 dlm = mle->dlm;
252
253 spin_lock(&dlm->spinlock);
254 spin_lock(&dlm->master_lock);
255 __dlm_put_mle(mle);
256 spin_unlock(&dlm->master_lock);
257 spin_unlock(&dlm->spinlock);
258}
259
260static inline void dlm_get_mle(struct dlm_master_list_entry *mle)
261{
262 kref_get(&mle->mle_refs);
263}
264
265static void dlm_init_mle(struct dlm_master_list_entry *mle,
266 enum dlm_mle_type type,
267 struct dlm_ctxt *dlm,
268 struct dlm_lock_resource *res,
269 const char *name,
270 unsigned int namelen)
271{
272 assert_spin_locked(&dlm->spinlock);
273
274 mle->dlm = dlm;
275 mle->type = type;
2ed6c750 276 INIT_HLIST_NODE(&mle->master_hash_node);
6714d8e8
KH		 277 INIT_LIST_HEAD(&mle->hb_events);
278 memset(mle->maybe_map, 0, sizeof(mle->maybe_map));
279 spin_lock_init(&mle->spinlock);
280 init_waitqueue_head(&mle->wq);
281 atomic_set(&mle->woken, 0);
282 kref_init(&mle->mle_refs);
283 memset(mle->response_map, 0, sizeof(mle->response_map));
284 mle->master = O2NM_MAX_NODES;
285 mle->new_master = O2NM_MAX_NODES;
a2bf0477 286 mle->inuse = 0;
6714d8e8 287
f77a9a78
SM		 288 BUG_ON(mle->type != DLM_MLE_BLOCK &&
289 mle->type != DLM_MLE_MASTER &&
290 mle->type != DLM_MLE_MIGRATION);
291
6714d8e8
KH		 292 if (mle->type == DLM_MLE_MASTER) {
293 BUG_ON(!res);
7141514b
SM		 294 mle->mleres = res;
295 memcpy(mle->mname, res->lockname.name, res->lockname.len);
296 mle->mnamelen = res->lockname.len;
297 mle->mnamehash = res->lockname.hash;
f77a9a78 298 } else {
6714d8e8 299 BUG_ON(!name);
7141514b
SM		 300 mle->mleres = NULL;
301 memcpy(mle->mname, name, namelen);
302 mle->mnamelen = namelen;
303 mle->mnamehash = dlm_lockid_hash(name, namelen);
6714d8e8
KH		 304 }
305
2041d8fd
SM		 306 atomic_inc(&dlm->mle_tot_count[mle->type]);
307 atomic_inc(&dlm->mle_cur_count[mle->type]);
308
6714d8e8
KH		 309 /* copy off the node_map and register hb callbacks on our copy */
310 memcpy(mle->node_map, dlm->domain_map, sizeof(mle->node_map));
311 memcpy(mle->vote_map, dlm->domain_map, sizeof(mle->vote_map));
312 clear_bit(dlm->node_num, mle->vote_map);
313 clear_bit(dlm->node_num, mle->node_map);
314
315 /* attach the mle to the domain node up/down events */
316 __dlm_mle_attach_hb_events(dlm, mle);
317}
318
1c084577
SM		 319void __dlm_unlink_mle(struct dlm_ctxt *dlm, struct dlm_master_list_entry *mle)
320{
321 assert_spin_locked(&dlm->spinlock);
322 assert_spin_locked(&dlm->master_lock);
323
2ed6c750
SM		 324 if (!hlist_unhashed(&mle->master_hash_node))
325 hlist_del_init(&mle->master_hash_node);
1c084577
SM		 326}
327
328void __dlm_insert_mle(struct dlm_ctxt *dlm, struct dlm_master_list_entry *mle)
329{
2ed6c750 330 struct hlist_head *bucket;
2ed6c750 331
1c084577
SM		 332 assert_spin_locked(&dlm->master_lock);
333
7141514b 334 bucket = dlm_master_hash(dlm, mle->mnamehash);
2ed6c750 335 hlist_add_head(&mle->master_hash_node, bucket);
1c084577 336}
6714d8e8
KH		 337
338/* returns 1 if found, 0 if not */
339static int dlm_find_mle(struct dlm_ctxt *dlm,
340 struct dlm_master_list_entry **mle,
341 char *name, unsigned int namelen)
342{
343 struct dlm_master_list_entry *tmpmle;
2ed6c750 344 struct hlist_head *bucket;
2ed6c750 345 unsigned int hash;
6714d8e8
KH		 346
347 assert_spin_locked(&dlm->master_lock);
348
2ed6c750
SM		 349 hash = dlm_lockid_hash(name, namelen);
350 bucket = dlm_master_hash(dlm, hash);
df53cd3b 351 hlist_for_each_entry(tmpmle, bucket, master_hash_node) {
6714d8e8
KH		 352 if (!dlm_mle_equal(dlm, tmpmle, name, namelen))
353 continue;
354 dlm_get_mle(tmpmle);
355 *mle = tmpmle;
356 return 1;
357 }
358 return 0;
359}
360
361void dlm_hb_event_notify_attached(struct dlm_ctxt *dlm, int idx, int node_up)
362{
363 struct dlm_master_list_entry *mle;
6714d8e8
KH		 364
365 assert_spin_locked(&dlm->spinlock);
2bd63216 366
800deef3 367 list_for_each_entry(mle, &dlm->mle_hb_events, hb_events) {
6714d8e8
KH		 368 if (node_up)
369 dlm_mle_node_up(dlm, mle, NULL, idx);
370 else
371 dlm_mle_node_down(dlm, mle, NULL, idx);
372 }
373}
374
375static void dlm_mle_node_down(struct dlm_ctxt *dlm,
376 struct dlm_master_list_entry *mle,
377 struct o2nm_node *node, int idx)
378{
379 spin_lock(&mle->spinlock);
380
381 if (!test_bit(idx, mle->node_map))
382 mlog(0, "node %u already removed from nodemap!\n", idx);
383 else
384 clear_bit(idx, mle->node_map);
385
386 spin_unlock(&mle->spinlock);
387}
388
389static void dlm_mle_node_up(struct dlm_ctxt *dlm,
390 struct dlm_master_list_entry *mle,
391 struct o2nm_node *node, int idx)
392{
393 spin_lock(&mle->spinlock);
394
395 if (test_bit(idx, mle->node_map))
396 mlog(0, "node %u already in node map!\n", idx);
397 else
398 set_bit(idx, mle->node_map);
399
400 spin_unlock(&mle->spinlock);
401}
402
403
404int dlm_init_mle_cache(void)
405{
12eb0035 406 dlm_mle_cache = kmem_cache_create("o2dlm_mle",
6714d8e8
KH		 407 sizeof(struct dlm_master_list_entry),
408 0, SLAB_HWCACHE_ALIGN,
20c2df83 409 NULL);
6714d8e8
KH		 410 if (dlm_mle_cache == NULL)
411 return -ENOMEM;
412 return 0;
413}
414
415void dlm_destroy_mle_cache(void)
416{
417 if (dlm_mle_cache)
418 kmem_cache_destroy(dlm_mle_cache);
419}
420
421static void dlm_mle_release(struct kref *kref)
422{
423 struct dlm_master_list_entry *mle;
424 struct dlm_ctxt *dlm;
425
6714d8e8
KH		 426 mle = container_of(kref, struct dlm_master_list_entry, mle_refs);
427 dlm = mle->dlm;
428
6714d8e8
KH		 429 assert_spin_locked(&dlm->spinlock);
430 assert_spin_locked(&dlm->master_lock);
431
7141514b
SM		 432 mlog(0, "Releasing mle for %.*s, type %d\n", mle->mnamelen, mle->mname,
433 mle->type);
2ed6c750 434
6714d8e8 435 /* remove from list if not already */
1c084577 436 __dlm_unlink_mle(dlm, mle);
6714d8e8
KH		 437
438 /* detach the mle from the domain node up/down events */
439 __dlm_mle_detach_hb_events(dlm, mle);
440
2041d8fd
SM		 441 atomic_dec(&dlm->mle_cur_count[mle->type]);
442
6714d8e8
KH		 443 /* NOTE: kfree under spinlock here.
444 * if this is bad, we can move this to a freelist. */
445 kmem_cache_free(dlm_mle_cache, mle);
446}
447
448
449/*
450 * LOCK RESOURCE FUNCTIONS
451 */
452
724bdca9
SM		 453int dlm_init_master_caches(void)
454{
455 dlm_lockres_cache = kmem_cache_create("o2dlm_lockres",
456 sizeof(struct dlm_lock_resource),
457 0, SLAB_HWCACHE_ALIGN, NULL);
458 if (!dlm_lockres_cache)
459 goto bail;
460
461 dlm_lockname_cache = kmem_cache_create("o2dlm_lockname",
462 DLM_LOCKID_NAME_MAX, 0,
463 SLAB_HWCACHE_ALIGN, NULL);
464 if (!dlm_lockname_cache)
465 goto bail;
466
467 return 0;
468bail:
469 dlm_destroy_master_caches();
470 return -ENOMEM;
471}
472
473void dlm_destroy_master_caches(void)
474{
66db6cfd 475 if (dlm_lockname_cache) {
724bdca9 476 kmem_cache_destroy(dlm_lockname_cache);
66db6cfd
JQ		 477 dlm_lockname_cache = NULL;
478 }
724bdca9 479
66db6cfd 480 if (dlm_lockres_cache) {
724bdca9 481 kmem_cache_destroy(dlm_lockres_cache);
66db6cfd
JQ		 482 dlm_lockres_cache = NULL;
483 }
724bdca9
SM		 484}
485
6714d8e8
KH		 486static void dlm_lockres_release(struct kref *kref)
487{
488 struct dlm_lock_resource *res;
b0d4f817 489 struct dlm_ctxt *dlm;
6714d8e8
KH		 490
491 res = container_of(kref, struct dlm_lock_resource, refs);
b0d4f817 492 dlm = res->dlm;
6714d8e8
KH		 493
494 /* This should not happen -- all lockres' have a name
495 * associated with them at init time. */
496 BUG_ON(!res->lockname.name);
497
498 mlog(0, "destroying lockres %.*s\n", res->lockname.len,
499 res->lockname.name);
500
6800791a
SM		 501 atomic_dec(&dlm->res_cur_count);
502
a7f90d83
KH		 503 if (!hlist_unhashed(&res->hash_node) ||
504 !list_empty(&res->granted) ||
505 !list_empty(&res->converting) ||
506 !list_empty(&res->blocked) ||
507 !list_empty(&res->dirty) ||
508 !list_empty(&res->recovering) ||
509 !list_empty(&res->purge)) {
510 mlog(ML_ERROR,
511 "Going to BUG for resource %.*s."
512 " We're on a list! [%c%c%c%c%c%c%c]\n",
513 res->lockname.len, res->lockname.name,
514 !hlist_unhashed(&res->hash_node) ? 'H' : ' ',
515 !list_empty(&res->granted) ? 'G' : ' ',
516 !list_empty(&res->converting) ? 'C' : ' ',
517 !list_empty(&res->blocked) ? 'B' : ' ',
518 !list_empty(&res->dirty) ? 'D' : ' ',
519 !list_empty(&res->recovering) ? 'R' : ' ',
520 !list_empty(&res->purge) ? 'P' : ' ');
521
522 dlm_print_one_lock_resource(res);
523 }
524
6714d8e8
KH		 525 /* By the time we're ready to blow this guy away, we shouldn't
526 * be on any lists. */
81f2094a 527 BUG_ON(!hlist_unhashed(&res->hash_node));
6714d8e8
KH		 528 BUG_ON(!list_empty(&res->granted));
529 BUG_ON(!list_empty(&res->converting));
530 BUG_ON(!list_empty(&res->blocked));
531 BUG_ON(!list_empty(&res->dirty));
532 BUG_ON(!list_empty(&res->recovering));
533 BUG_ON(!list_empty(&res->purge));
534
724bdca9 535 kmem_cache_free(dlm_lockname_cache, (void *)res->lockname.name);
6714d8e8 536
724bdca9 537 kmem_cache_free(dlm_lockres_cache, res);
6714d8e8
KH		 538}
539
6714d8e8
KH		 540void dlm_lockres_put(struct dlm_lock_resource *res)
541{
542 kref_put(&res->refs, dlm_lockres_release);
543}
544
545static void dlm_init_lockres(struct dlm_ctxt *dlm,
546 struct dlm_lock_resource *res,
547 const char *name, unsigned int namelen)
548{
549 char *qname;
550
551 /* If we memset here, we lose our reference to the kmalloc'd
552 * res->lockname.name, so be sure to init every field
553 * correctly! */
554
555 qname = (char *) res->lockname.name;
556 memcpy(qname, name, namelen);
557
558 res->lockname.len = namelen;
a3d33291 559 res->lockname.hash = dlm_lockid_hash(name, namelen);
6714d8e8
KH		 560
561 init_waitqueue_head(&res->wq);
562 spin_lock_init(&res->spinlock);
81f2094a 563 INIT_HLIST_NODE(&res->hash_node);
6714d8e8
KH		 564 INIT_LIST_HEAD(&res->granted);
565 INIT_LIST_HEAD(&res->converting);
566 INIT_LIST_HEAD(&res->blocked);
567 INIT_LIST_HEAD(&res->dirty);
568 INIT_LIST_HEAD(&res->recovering);
569 INIT_LIST_HEAD(&res->purge);
29576f8b 570 INIT_LIST_HEAD(&res->tracking);
6714d8e8
KH		 571 atomic_set(&res->asts_reserved, 0);
572 res->migration_pending = 0;
ba2bf218 573 res->inflight_locks = 0;
ac4fef4d 574 res->inflight_assert_workers = 0;
6714d8e8 575
b0d4f817
SM		 576 res->dlm = dlm;
577
6714d8e8
KH		 578 kref_init(&res->refs);
579
6800791a
SM		 580 atomic_inc(&dlm->res_tot_count);
581 atomic_inc(&dlm->res_cur_count);
582
6714d8e8
KH		 583 /* just for consistency */
584 spin_lock(&res->spinlock);
585 dlm_set_lockres_owner(dlm, res, DLM_LOCK_RES_OWNER_UNKNOWN);
586 spin_unlock(&res->spinlock);
587
588 res->state = DLM_LOCK_RES_IN_PROGRESS;
589
590 res->last_used = 0;
591
18c6ac38 592 spin_lock(&dlm->spinlock);
29576f8b 593 list_add_tail(&res->tracking, &dlm->tracking_list);
18c6ac38 594 spin_unlock(&dlm->spinlock);
29576f8b 595
6714d8e8 596 memset(res->lvb, 0, DLM_LVB_LEN);
ba2bf218 597 memset(res->refmap, 0, sizeof(res->refmap));
6714d8e8
KH		 598}
599
600struct dlm_lock_resource *dlm_new_lockres(struct dlm_ctxt *dlm,
601 const char *name,
602 unsigned int namelen)
603{
724bdca9 604 struct dlm_lock_resource *res = NULL;
6714d8e8 605
3914ed0c 606 res = kmem_cache_zalloc(dlm_lockres_cache, GFP_NOFS);
6714d8e8 607 if (!res)
724bdca9 608 goto error;
6714d8e8 609
3914ed0c 610 res->lockname.name = kmem_cache_zalloc(dlm_lockname_cache, GFP_NOFS);
724bdca9
SM		 611 if (!res->lockname.name)
612 goto error;
6714d8e8
KH		 613
614 dlm_init_lockres(dlm, res, name, namelen);
615 return res;
724bdca9
SM		 616
617error:
724bdca9
SM		 618 if (res)
619 kmem_cache_free(dlm_lockres_cache, res);
620 return NULL;
6714d8e8
KH		 621}
622
8d400b81
SM		 623void dlm_lockres_set_refmap_bit(struct dlm_ctxt *dlm,
624 struct dlm_lock_resource *res, int bit)
ba2bf218 625{
8d400b81
SM		 626 assert_spin_locked(&res->spinlock);
627
628 mlog(0, "res %.*s, set node %u, %ps()\n", res->lockname.len,
629 res->lockname.name, bit, __builtin_return_address(0));
630
631 set_bit(bit, res->refmap);
632}
633
634void dlm_lockres_clear_refmap_bit(struct dlm_ctxt *dlm,
635 struct dlm_lock_resource *res, int bit)
636{
637 assert_spin_locked(&res->spinlock);
638
639 mlog(0, "res %.*s, clr node %u, %ps()\n", res->lockname.len,
640 res->lockname.name, bit, __builtin_return_address(0));
641
642 clear_bit(bit, res->refmap);
643}
644
5760a97c 645static void __dlm_lockres_grab_inflight_ref(struct dlm_ctxt *dlm,
8d400b81
SM		 646 struct dlm_lock_resource *res)
647{
ba2bf218 648 res->inflight_locks++;
ff0a522e 649
8d400b81
SM		 650 mlog(0, "%s: res %.*s, inflight++: now %u, %ps()\n", dlm->name,
651 res->lockname.len, res->lockname.name, res->inflight_locks,
652 __builtin_return_address(0));
ba2bf218
KH		 653}
654
5760a97c
JQ		 655void dlm_lockres_grab_inflight_ref(struct dlm_ctxt *dlm,
656 struct dlm_lock_resource *res)
657{
658 assert_spin_locked(&res->spinlock);
659 __dlm_lockres_grab_inflight_ref(dlm, res);
660}
661
8d400b81
SM		 662void dlm_lockres_drop_inflight_ref(struct dlm_ctxt *dlm,
663 struct dlm_lock_resource *res)
ba2bf218
KH		 664{
665 assert_spin_locked(&res->spinlock);
666
667 BUG_ON(res->inflight_locks == 0);
8d400b81 668
ba2bf218 669 res->inflight_locks--;
ff0a522e 670
8d400b81
SM		 671 mlog(0, "%s: res %.*s, inflight--: now %u, %ps()\n", dlm->name,
672 res->lockname.len, res->lockname.name, res->inflight_locks,
673 __builtin_return_address(0));
674
ba2bf218
KH		 675 wake_up(&res->wq);
676}
677
ac4fef4d
X		 678void __dlm_lockres_grab_inflight_worker(struct dlm_ctxt *dlm,
679 struct dlm_lock_resource *res)
680{
681 assert_spin_locked(&res->spinlock);
682 res->inflight_assert_workers++;
683 mlog(0, "%s:%.*s: inflight assert worker++: now %u\n",
684 dlm->name, res->lockname.len, res->lockname.name,
685 res->inflight_assert_workers);
686}
687
ac4fef4d
X		 688static void __dlm_lockres_drop_inflight_worker(struct dlm_ctxt *dlm,
689 struct dlm_lock_resource *res)
690{
691 assert_spin_locked(&res->spinlock);
692 BUG_ON(res->inflight_assert_workers == 0);
693 res->inflight_assert_workers--;
694 mlog(0, "%s:%.*s: inflight assert worker--: now %u\n",
695 dlm->name, res->lockname.len, res->lockname.name,
696 res->inflight_assert_workers);
697}
698
699static void dlm_lockres_drop_inflight_worker(struct dlm_ctxt *dlm,
700 struct dlm_lock_resource *res)
701{
702 spin_lock(&res->spinlock);
703 __dlm_lockres_drop_inflight_worker(dlm, res);
704 spin_unlock(&res->spinlock);
705}
706
6714d8e8
KH		 707/*
708 * lookup a lock resource by name.
709 * may already exist in the hashtable.
710 * lockid is null terminated
711 *
712 * if not, allocate enough for the lockres and for
713 * the temporary structure used in doing the mastering.
714 *
715 * also, do a lookup in the dlm->master_list to see
716 * if another node has begun mastering the same lock.
717 * if so, there should be a block entry in there
718 * for this name, and we should *not* attempt to master
719 * the lock here. need to wait around for that node
720 * to assert_master (or die).
721 *
722 */
723struct dlm_lock_resource * dlm_get_lock_resource(struct dlm_ctxt *dlm,
724 const char *lockid,
3384f3df 725 int namelen,
6714d8e8
KH		 726 int flags)
727{
728 struct dlm_lock_resource *tmpres=NULL, *res=NULL;
729 struct dlm_master_list_entry *mle = NULL;
730 struct dlm_master_list_entry *alloc_mle = NULL;
731 int blocked = 0;
732 int ret, nodenum;
733 struct dlm_node_iter iter;
3384f3df 734 unsigned int hash;
6714d8e8 735 int tries = 0;
c03872f5 736 int bit, wait_on_recovery = 0;
6714d8e8
KH		 737
738 BUG_ON(!lockid);
739
a3d33291 740 hash = dlm_lockid_hash(lockid, namelen);
6714d8e8
KH		 741
742 mlog(0, "get lockres %s (len %d)\n", lockid, namelen);
743
744lookup:
745 spin_lock(&dlm->spinlock);
ba2bf218 746 tmpres = __dlm_lookup_lockres_full(dlm, lockid, namelen, hash);
6714d8e8 747 if (tmpres) {
7b791d68 748 spin_unlock(&dlm->spinlock);
ba2bf218 749 spin_lock(&tmpres->spinlock);
b1432a2a
JB		 750
751 /*
752 * Right after dlm spinlock was released, dlm_thread could have
753 * purged the lockres. Check if lockres got unhashed. If so
754 * start over.
755 */
756 if (hlist_unhashed(&tmpres->hash_node)) {
757 spin_unlock(&tmpres->spinlock);
758 dlm_lockres_put(tmpres);
759 tmpres = NULL;
760 goto lookup;
761 }
762
ff0a522e 763 /* Wait on the thread that is mastering the resource */
7b791d68
SM		 764 if (tmpres->owner == DLM_LOCK_RES_OWNER_UNKNOWN) {
765 __dlm_wait_on_lockres(tmpres);
766 BUG_ON(tmpres->owner == DLM_LOCK_RES_OWNER_UNKNOWN);
ff0a522e
SM		 767 spin_unlock(&tmpres->spinlock);
768 dlm_lockres_put(tmpres);
769 tmpres = NULL;
770 goto lookup;
7b791d68
SM		 771 }
772
ff0a522e
SM		 773 /* Wait on the resource purge to complete before continuing */
774 if (tmpres->state & DLM_LOCK_RES_DROPPING_REF) {
775 BUG_ON(tmpres->owner == dlm->node_num);
776 __dlm_wait_on_lockres_flags(tmpres,
777 DLM_LOCK_RES_DROPPING_REF);
ba2bf218
KH		 778 spin_unlock(&tmpres->spinlock);
779 dlm_lockres_put(tmpres);
780 tmpres = NULL;
781 goto lookup;
782 }
783
ff0a522e
SM		 784 /* Grab inflight ref to pin the resource */
785 dlm_lockres_grab_inflight_ref(dlm, tmpres);
786
787 spin_unlock(&tmpres->spinlock);
f57a22dd
YJ		 788 if (res) {
789 spin_lock(&dlm->track_lock);
790 if (!list_empty(&res->tracking))
791 list_del_init(&res->tracking);
792 else
793 mlog(ML_ERROR, "Resource %.*s not "
794 "on the Tracking list\n",
795 res->lockname.len,
796 res->lockname.name);
797 spin_unlock(&dlm->track_lock);
6714d8e8 798 dlm_lockres_put(res);
f57a22dd 799 }
6714d8e8
KH		 800 res = tmpres;
801 goto leave;
802 }
803
804 if (!res) {
805 spin_unlock(&dlm->spinlock);
806 mlog(0, "allocating a new resource\n");
807 /* nothing found and we need to allocate one. */
3914ed0c 808 alloc_mle = kmem_cache_alloc(dlm_mle_cache, GFP_NOFS);
6714d8e8
KH		 809 if (!alloc_mle)
810 goto leave;
811 res = dlm_new_lockres(dlm, lockid, namelen);
812 if (!res)
813 goto leave;
814 goto lookup;
815 }
816
817 mlog(0, "no lockres found, allocated our own: %p\n", res);
818
819 if (flags & LKM_LOCAL) {
820 /* caller knows it's safe to assume it's not mastered elsewhere
821 * DONE! return right away */
822 spin_lock(&res->spinlock);
823 dlm_change_lockres_owner(dlm, res, dlm->node_num);
824 __dlm_insert_lockres(dlm, res);
ba2bf218 825 dlm_lockres_grab_inflight_ref(dlm, res);
6714d8e8
KH		 826 spin_unlock(&res->spinlock);
827 spin_unlock(&dlm->spinlock);
828 /* lockres still marked IN_PROGRESS */
829 goto wake_waiters;
830 }
831
832 /* check master list to see if another node has started mastering it */
833 spin_lock(&dlm->master_lock);
834
835 /* if we found a block, wait for lock to be mastered by another node */
836 blocked = dlm_find_mle(dlm, &mle, (char *)lockid, namelen);
837 if (blocked) {
ba2bf218 838 int mig;
6714d8e8
KH		 839 if (mle->type == DLM_MLE_MASTER) {
840 mlog(ML_ERROR, "master entry for nonexistent lock!\n");
841 BUG();
ba2bf218
KH		 842 }
843 mig = (mle->type == DLM_MLE_MIGRATION);
844 /* if there is a migration in progress, let the migration
845 * finish before continuing. we can wait for the absence
846 * of the MIGRATION mle: either the migrate finished or
847 * one of the nodes died and the mle was cleaned up.
848 * if there is a BLOCK here, but it already has a master
849 * set, we are too late. the master does not have a ref
850 * for us in the refmap. detach the mle and drop it.
851 * either way, go back to the top and start over. */
852 if (mig || mle->master != O2NM_MAX_NODES) {
853 BUG_ON(mig && mle->master == dlm->node_num);
854 /* we arrived too late. the master does not
855 * have a ref for us. retry. */
856 mlog(0, "%s:%.*s: late on %s\n",
857 dlm->name, namelen, lockid,
858 mig ? "MIGRATION" : "BLOCK");
6714d8e8 859 spin_unlock(&dlm->master_lock);
6714d8e8
KH		 860 spin_unlock(&dlm->spinlock);
861
862 /* master is known, detach */
ba2bf218
KH		 863 if (!mig)
864 dlm_mle_detach_hb_events(dlm, mle);
6714d8e8
KH		 865 dlm_put_mle(mle);
866 mle = NULL;
25985edc 867 /* this is lame, but we can't wait on either
ba2bf218
KH		 868 * the mle or lockres waitqueue here */
869 if (mig)
870 msleep(100);
871 goto lookup;
6714d8e8
KH		 872 }
873 } else {
874 /* go ahead and try to master lock on this node */
875 mle = alloc_mle;
876 /* make sure this does not get freed below */
877 alloc_mle = NULL;
878 dlm_init_mle(mle, DLM_MLE_MASTER, dlm, res, NULL, 0);
879 set_bit(dlm->node_num, mle->maybe_map);
1c084577 880 __dlm_insert_mle(dlm, mle);
c03872f5
KH		 881
882 /* still holding the dlm spinlock, check the recovery map
2bd63216 883 * to see if there are any nodes that still need to be
c03872f5
KH		 884 * considered. these will not appear in the mle nodemap
885 * but they might own this lockres. wait on them. */
886 bit = find_next_bit(dlm->recovery_map, O2NM_MAX_NODES, 0);
887 if (bit < O2NM_MAX_NODES) {
8decab3c
SM		 888 mlog(0, "%s: res %.*s, At least one node (%d) "
889 "to recover before lock mastery can begin\n",
c03872f5
KH		 890 dlm->name, namelen, (char *)lockid, bit);
891 wait_on_recovery = 1;
892 }
6714d8e8
KH		 893 }
894
895 /* at this point there is either a DLM_MLE_BLOCK or a
896 * DLM_MLE_MASTER on the master list, so it's safe to add the
897 * lockres to the hashtable. anyone who finds the lock will
898 * still have to wait on the IN_PROGRESS. */
899
900 /* finally add the lockres to its hash bucket */
901 __dlm_insert_lockres(dlm, res);
8d400b81 902
5760a97c
JQ		 903 /* since this lockres is new it doesn't not require the spinlock */
904 __dlm_lockres_grab_inflight_ref(dlm, res);
ba2bf218 905
6714d8e8
KH		 906 /* get an extra ref on the mle in case this is a BLOCK
907 * if so, the creator of the BLOCK may try to put the last
908 * ref at this time in the assert master handler, so we
909 * need an extra one to keep from a bad ptr deref. */
a2bf0477 910 dlm_get_mle_inuse(mle);
6714d8e8
KH		 911 spin_unlock(&dlm->master_lock);
912 spin_unlock(&dlm->spinlock);
913
e7e69eb3 914redo_request:
c03872f5
KH		 915 while (wait_on_recovery) {
916 /* any cluster changes that occurred after dropping the
917 * dlm spinlock would be detectable be a change on the mle,
918 * so we only need to clear out the recovery map once. */
919 if (dlm_is_recovery_lock(lockid, namelen)) {
8decab3c
SM		 920 mlog(0, "%s: Recovery map is not empty, but must "
921 "master $RECOVERY lock now\n", dlm->name);
c03872f5
KH		 922 if (!dlm_pre_master_reco_lockres(dlm, res))
923 wait_on_recovery = 0;
924 else {
925 mlog(0, "%s: waiting 500ms for heartbeat state "
926 "change\n", dlm->name);
927 msleep(500);
928 }
929 continue;
2bd63216 930 }
c03872f5
KH		 931
932 dlm_kick_recovery_thread(dlm);
aa087b84 933 msleep(1000);
c03872f5
KH		 934 dlm_wait_for_recovery(dlm);
935
936 spin_lock(&dlm->spinlock);
937 bit = find_next_bit(dlm->recovery_map, O2NM_MAX_NODES, 0);
938 if (bit < O2NM_MAX_NODES) {
8decab3c
SM		 939 mlog(0, "%s: res %.*s, At least one node (%d) "
940 "to recover before lock mastery can begin\n",
c03872f5
KH		 941 dlm->name, namelen, (char *)lockid, bit);
942 wait_on_recovery = 1;
943 } else
944 wait_on_recovery = 0;
945 spin_unlock(&dlm->spinlock);
b7084ab5
KH		 946
947 if (wait_on_recovery)
948 dlm_wait_for_node_recovery(dlm, bit, 10000);
c03872f5
KH		 949 }
950
6714d8e8
KH		 951 /* must wait for lock to be mastered elsewhere */
952 if (blocked)
953 goto wait;
954
6714d8e8
KH		 955 ret = -EINVAL;
956 dlm_node_iter_init(mle->vote_map, &iter);
957 while ((nodenum = dlm_node_iter_next(&iter)) >= 0) {
ba2bf218 958 ret = dlm_do_master_request(res, mle, nodenum);
6714d8e8
KH		 959 if (ret < 0)
960 mlog_errno(ret);
961 if (mle->master != O2NM_MAX_NODES) {
962 /* found a master ! */
9c6510a5
KH		 963 if (mle->master <= nodenum)
964 break;
965 /* if our master request has not reached the master
966 * yet, keep going until it does. this is how the
967 * master will know that asserts are needed back to
968 * the lower nodes. */
8decab3c
SM		 969 mlog(0, "%s: res %.*s, Requests only up to %u but "
970 "master is %u, keep going\n", dlm->name, namelen,
9c6510a5 971 lockid, nodenum, mle->master);
6714d8e8
KH		 972 }
973 }
974
975wait:
976 /* keep going until the response map includes all nodes */
977 ret = dlm_wait_for_lock_mastery(dlm, res, mle, &blocked);
978 if (ret < 0) {
e7e69eb3 979 wait_on_recovery = 1;
8decab3c
SM		 980 mlog(0, "%s: res %.*s, Node map changed, redo the master "
981 "request now, blocked=%d\n", dlm->name, res->lockname.len,
6714d8e8
KH		 982 res->lockname.name, blocked);
983 if (++tries > 20) {
8decab3c
SM		 984 mlog(ML_ERROR, "%s: res %.*s, Spinning on "
985 "dlm_wait_for_lock_mastery, blocked = %d\n",
2bd63216 986 dlm->name, res->lockname.len,
6714d8e8
KH		 987 res->lockname.name, blocked);
988 dlm_print_one_lock_resource(res);
8a9343fa 989 dlm_print_one_mle(mle);
6714d8e8
KH		 990 tries = 0;
991 }
992 goto redo_request;
993 }
994
8decab3c
SM		 995 mlog(0, "%s: res %.*s, Mastered by %u\n", dlm->name, res->lockname.len,
996 res->lockname.name, res->owner);
6714d8e8
KH		 997 /* make sure we never continue without this */
998 BUG_ON(res->owner == O2NM_MAX_NODES);
999
1000 /* master is known, detach if not already detached */
1001 dlm_mle_detach_hb_events(dlm, mle);
1002 dlm_put_mle(mle);
1003 /* put the extra ref */
a2bf0477 1004 dlm_put_mle_inuse(mle);
6714d8e8
KH		 1005
1006wake_waiters:
1007 spin_lock(&res->spinlock);
1008 res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
1009 spin_unlock(&res->spinlock);
1010 wake_up(&res->wq);
1011
1012leave:
1013 /* need to free the unused mle */
1014 if (alloc_mle)
1015 kmem_cache_free(dlm_mle_cache, alloc_mle);
1016
1017 return res;
1018}
1019
1020
1021#define DLM_MASTERY_TIMEOUT_MS 5000
1022
1023static int dlm_wait_for_lock_mastery(struct dlm_ctxt *dlm,
1024 struct dlm_lock_resource *res,
1025 struct dlm_master_list_entry *mle,
1026 int *blocked)
1027{
1028 u8 m;
1029 int ret, bit;
1030 int map_changed, voting_done;
1031 int assert, sleep;
1032
1033recheck:
1034 ret = 0;
1035 assert = 0;
1036
1037 /* check if another node has already become the owner */
1038 spin_lock(&res->spinlock);
1039 if (res->owner != DLM_LOCK_RES_OWNER_UNKNOWN) {
9c6510a5
KH		 1040 mlog(0, "%s:%.*s: owner is suddenly %u\n", dlm->name,
1041 res->lockname.len, res->lockname.name, res->owner);
6714d8e8 1042 spin_unlock(&res->spinlock);
9c6510a5
KH		 1043 /* this will cause the master to re-assert across
1044 * the whole cluster, freeing up mles */
588e0090 1045 if (res->owner != dlm->node_num) {
ba2bf218 1046 ret = dlm_do_master_request(res, mle, res->owner);
588e0090
KH		 1047 if (ret < 0) {
1048 /* give recovery a chance to run */
1049 mlog(ML_ERROR, "link to %u went down?: %d\n", res->owner, ret);
1050 msleep(500);
1051 goto recheck;
1052 }
9c6510a5
KH		 1053 }
1054 ret = 0;
6714d8e8
KH		 1055 goto leave;
1056 }
1057 spin_unlock(&res->spinlock);
1058
1059 spin_lock(&mle->spinlock);
1060 m = mle->master;
1061 map_changed = (memcmp(mle->vote_map, mle->node_map,
1062 sizeof(mle->vote_map)) != 0);
1063 voting_done = (memcmp(mle->vote_map, mle->response_map,
1064 sizeof(mle->vote_map)) == 0);
1065
1066 /* restart if we hit any errors */
1067 if (map_changed) {
1068 int b;
1069 mlog(0, "%s: %.*s: node map changed, restarting\n",
1070 dlm->name, res->lockname.len, res->lockname.name);
1071 ret = dlm_restart_lock_mastery(dlm, res, mle, *blocked);
1072 b = (mle->type == DLM_MLE_BLOCK);
1073 if ((*blocked && !b) || (!*blocked && b)) {
2bd63216 1074 mlog(0, "%s:%.*s: status change: old=%d new=%d\n",
6714d8e8
KH		 1075 dlm->name, res->lockname.len, res->lockname.name,
1076 *blocked, b);
1077 *blocked = b;
1078 }
1079 spin_unlock(&mle->spinlock);
1080 if (ret < 0) {
1081 mlog_errno(ret);
1082 goto leave;
1083 }
1084 mlog(0, "%s:%.*s: restart lock mastery succeeded, "
1085 "rechecking now\n", dlm->name, res->lockname.len,
1086 res->lockname.name);
1087 goto recheck;
aa852354
KH		 1088 } else {
1089 if (!voting_done) {
1090 mlog(0, "map not changed and voting not done "
1091 "for %s:%.*s\n", dlm->name, res->lockname.len,
1092 res->lockname.name);
1093 }
6714d8e8
KH		 1094 }
1095
1096 if (m != O2NM_MAX_NODES) {
1097 /* another node has done an assert!
1098 * all done! */
1099 sleep = 0;
1100 } else {
1101 sleep = 1;
1102 /* have all nodes responded? */
1103 if (voting_done && !*blocked) {
1104 bit = find_next_bit(mle->maybe_map, O2NM_MAX_NODES, 0);
1105 if (dlm->node_num <= bit) {
1106 /* my node number is lowest.
1107 * now tell other nodes that I am
1108 * mastering this. */
1109 mle->master = dlm->node_num;
ba2bf218
KH		 1110 /* ref was grabbed in get_lock_resource
1111 * will be dropped in dlmlock_master */
6714d8e8
KH		 1112 assert = 1;
1113 sleep = 0;
1114 }
1115 /* if voting is done, but we have not received
1116 * an assert master yet, we must sleep */
1117 }
1118 }
1119
1120 spin_unlock(&mle->spinlock);
1121
1122 /* sleep if we haven't finished voting yet */
1123 if (sleep) {
1124 unsigned long timeo = msecs_to_jiffies(DLM_MASTERY_TIMEOUT_MS);
1125
1126 /*
1127 if (atomic_read(&mle->mle_refs.refcount) < 2)
1128 mlog(ML_ERROR, "mle (%p) refs=%d, name=%.*s\n", mle,
1129 atomic_read(&mle->mle_refs.refcount),
1130 res->lockname.len, res->lockname.name);
1131 */
1132 atomic_set(&mle->woken, 0);
1133 (void)wait_event_timeout(mle->wq,
1134 (atomic_read(&mle->woken) == 1),
1135 timeo);
1136 if (res->owner == O2NM_MAX_NODES) {
ba2bf218
KH		 1137 mlog(0, "%s:%.*s: waiting again\n", dlm->name,
1138 res->lockname.len, res->lockname.name);
6714d8e8
KH		 1139 goto recheck;
1140 }
1141 mlog(0, "done waiting, master is %u\n", res->owner);
1142 ret = 0;
1143 goto leave;
1144 }
1145
1146 ret = 0; /* done */
1147 if (assert) {
1148 m = dlm->node_num;
1149 mlog(0, "about to master %.*s here, this=%u\n",
1150 res->lockname.len, res->lockname.name, m);
ba2bf218 1151 ret = dlm_do_assert_master(dlm, res, mle->vote_map, 0);
6714d8e8
KH		 1152 if (ret) {
1153 /* This is a failure in the network path,
1154 * not in the response to the assert_master
1155 * (any nonzero response is a BUG on this node).
1156 * Most likely a socket just got disconnected
1157 * due to node death. */
1158 mlog_errno(ret);
1159 }
1160 /* no longer need to restart lock mastery.
1161 * all living nodes have been contacted. */
1162 ret = 0;
1163 }
1164
1165 /* set the lockres owner */
1166 spin_lock(&res->spinlock);
ba2bf218
KH		 1167 /* mastery reference obtained either during
1168 * assert_master_handler or in get_lock_resource */
6714d8e8
KH		 1169 dlm_change_lockres_owner(dlm, res, m);
1170 spin_unlock(&res->spinlock);
1171
1172leave:
1173 return ret;
1174}
1175
1176struct dlm_bitmap_diff_iter
1177{
1178 int curnode;
1179 unsigned long *orig_bm;
1180 unsigned long *cur_bm;
1181 unsigned long diff_bm[BITS_TO_LONGS(O2NM_MAX_NODES)];
1182};
1183
1184enum dlm_node_state_change
1185{
1186 NODE_DOWN = -1,
1187 NODE_NO_CHANGE = 0,
1188 NODE_UP
1189};
1190
1191static void dlm_bitmap_diff_iter_init(struct dlm_bitmap_diff_iter *iter,
1192 unsigned long *orig_bm,
1193 unsigned long *cur_bm)
1194{
1195 unsigned long p1, p2;
1196 int i;
1197
1198 iter->curnode = -1;
1199 iter->orig_bm = orig_bm;
1200 iter->cur_bm = cur_bm;
1201
1202 for (i = 0; i < BITS_TO_LONGS(O2NM_MAX_NODES); i++) {
1203 p1 = *(iter->orig_bm + i);
1204 p2 = *(iter->cur_bm + i);
1205 iter->diff_bm[i] = (p1 & ~p2) | (p2 & ~p1);
1206 }
1207}
1208
1209static int dlm_bitmap_diff_iter_next(struct dlm_bitmap_diff_iter *iter,
1210 enum dlm_node_state_change *state)
1211{
1212 int bit;
1213
1214 if (iter->curnode >= O2NM_MAX_NODES)
1215 return -ENOENT;
1216
1217 bit = find_next_bit(iter->diff_bm, O2NM_MAX_NODES,
1218 iter->curnode+1);
1219 if (bit >= O2NM_MAX_NODES) {
1220 iter->curnode = O2NM_MAX_NODES;
1221 return -ENOENT;
1222 }
1223
1224 /* if it was there in the original then this node died */
1225 if (test_bit(bit, iter->orig_bm))
1226 *state = NODE_DOWN;
1227 else
1228 *state = NODE_UP;
1229
1230 iter->curnode = bit;
1231 return bit;
1232}
1233
1234
1235static int dlm_restart_lock_mastery(struct dlm_ctxt *dlm,
1236 struct dlm_lock_resource *res,
1237 struct dlm_master_list_entry *mle,
1238 int blocked)
1239{
1240 struct dlm_bitmap_diff_iter bdi;
1241 enum dlm_node_state_change sc;
1242 int node;
1243 int ret = 0;
1244
1245 mlog(0, "something happened such that the "
1246 "master process may need to be restarted!\n");
1247
1248 assert_spin_locked(&mle->spinlock);
1249
1250 dlm_bitmap_diff_iter_init(&bdi, mle->vote_map, mle->node_map);
1251 node = dlm_bitmap_diff_iter_next(&bdi, &sc);
1252 while (node >= 0) {
1253 if (sc == NODE_UP) {
e2faea4c
KH		 1254 /* a node came up. clear any old vote from
1255 * the response map and set it in the vote map
1256 * then restart the mastery. */
1257 mlog(ML_NOTICE, "node %d up while restarting\n", node);
6714d8e8
KH		 1258
1259 /* redo the master request, but only for the new node */
1260 mlog(0, "sending request to new node\n");
1261 clear_bit(node, mle->response_map);
1262 set_bit(node, mle->vote_map);
1263 } else {
1264 mlog(ML_ERROR, "node down! %d\n", node);
6714d8e8
KH		 1265 if (blocked) {
1266 int lowest = find_next_bit(mle->maybe_map,
1267 O2NM_MAX_NODES, 0);
1268
1269 /* act like it was never there */
1270 clear_bit(node, mle->maybe_map);
1271
e7e69eb3
KH		 1272 if (node == lowest) {
1273 mlog(0, "expected master %u died"
1274 " while this node was blocked "
1275 "waiting on it!\n", node);
1276 lowest = find_next_bit(mle->maybe_map,
1277 O2NM_MAX_NODES,
1278 lowest+1);
1279 if (lowest < O2NM_MAX_NODES) {
1280 mlog(0, "%s:%.*s:still "
1281 "blocked. waiting on %u "
1282 "now\n", dlm->name,
1283 res->lockname.len,
1284 res->lockname.name,
1285 lowest);
1286 } else {
1287 /* mle is an MLE_BLOCK, but
1288 * there is now nothing left to
1289 * block on. we need to return
1290 * all the way back out and try
1291 * again with an MLE_MASTER.
1292 * dlm_do_local_recovery_cleanup
1293 * has already run, so the mle
1294 * refcount is ok */
1295 mlog(0, "%s:%.*s: no "
1296 "longer blocking. try to "
1297 "master this here\n",
1298 dlm->name,
1299 res->lockname.len,
1300 res->lockname.name);
1301 mle->type = DLM_MLE_MASTER;
7141514b 1302 mle->mleres = res;
e7e69eb3 1303 }
6714d8e8 1304 }
6714d8e8
KH		 1305 }
1306
e7e69eb3
KH		 1307 /* now blank out everything, as if we had never
1308 * contacted anyone */
1309 memset(mle->maybe_map, 0, sizeof(mle->maybe_map));
1310 memset(mle->response_map, 0, sizeof(mle->response_map));
1311 /* reset the vote_map to the current node_map */
1312 memcpy(mle->vote_map, mle->node_map,
1313 sizeof(mle->node_map));
1314 /* put myself into the maybe map */
1315 if (mle->type != DLM_MLE_BLOCK)
1316 set_bit(dlm->node_num, mle->maybe_map);
6714d8e8
KH		 1317 }
1318 ret = -EAGAIN;
6714d8e8
KH		 1319 node = dlm_bitmap_diff_iter_next(&bdi, &sc);
1320 }
1321 return ret;
1322}
1323
1324
1325/*
1326 * DLM_MASTER_REQUEST_MSG
1327 *
1328 * returns: 0 on success,
1329 * -errno on a network error
1330 *
1331 * on error, the caller should assume the target node is "dead"
1332 *
1333 */
1334
ba2bf218
KH		 1335static int dlm_do_master_request(struct dlm_lock_resource *res,
1336 struct dlm_master_list_entry *mle, int to)
6714d8e8
KH		 1337{
1338 struct dlm_ctxt *dlm = mle->dlm;
1339 struct dlm_master_request request;
1340 int ret, response=0, resend;
1341
1342 memset(&request, 0, sizeof(request));
1343 request.node_idx = dlm->node_num;
1344
1345 BUG_ON(mle->type == DLM_MLE_MIGRATION);
1346
7141514b
SM		 1347 request.namelen = (u8)mle->mnamelen;
1348 memcpy(request.name, mle->mname, request.namelen);
6714d8e8
KH		 1349
1350again:
1351 ret = o2net_send_message(DLM_MASTER_REQUEST_MSG, dlm->key, &request,
1352 sizeof(request), to, &response);
1353 if (ret < 0) {
1354 if (ret == -ESRCH) {
1355 /* should never happen */
1356 mlog(ML_ERROR, "TCP stack not ready!\n");
1357 BUG();
1358 } else if (ret == -EINVAL) {
1359 mlog(ML_ERROR, "bad args passed to o2net!\n");
1360 BUG();
1361 } else if (ret == -ENOMEM) {
1362 mlog(ML_ERROR, "out of memory while trying to send "
1363 "network message! retrying\n");
1364 /* this is totally crude */
1365 msleep(50);
1366 goto again;
1367 } else if (!dlm_is_host_down(ret)) {
1368 /* not a network error. bad. */
1369 mlog_errno(ret);
1370 mlog(ML_ERROR, "unhandled error!");
1371 BUG();
1372 }
1373 /* all other errors should be network errors,
1374 * and likely indicate node death */
1375 mlog(ML_ERROR, "link to %d went down!\n", to);
1376 goto out;
1377 }
1378
1379 ret = 0;
1380 resend = 0;
1381 spin_lock(&mle->spinlock);
1382 switch (response) {
1383 case DLM_MASTER_RESP_YES:
1384 set_bit(to, mle->response_map);
1385 mlog(0, "node %u is the master, response=YES\n", to);
ba2bf218
KH		 1386 mlog(0, "%s:%.*s: master node %u now knows I have a "
1387 "reference\n", dlm->name, res->lockname.len,
1388 res->lockname.name, to);
6714d8e8
KH		 1389 mle->master = to;
1390 break;
1391 case DLM_MASTER_RESP_NO:
1392 mlog(0, "node %u not master, response=NO\n", to);
1393 set_bit(to, mle->response_map);
1394 break;
1395 case DLM_MASTER_RESP_MAYBE:
1396 mlog(0, "node %u not master, response=MAYBE\n", to);
1397 set_bit(to, mle->response_map);
1398 set_bit(to, mle->maybe_map);
1399 break;
1400 case DLM_MASTER_RESP_ERROR:
1401 mlog(0, "node %u hit an error, resending\n", to);
1402 resend = 1;
1403 response = 0;
1404 break;
1405 default:
1406 mlog(ML_ERROR, "bad response! %u\n", response);
1407 BUG();
1408 }
1409 spin_unlock(&mle->spinlock);
1410 if (resend) {
1411 /* this is also totally crude */
1412 msleep(50);
1413 goto again;
1414 }
1415
1416out:
1417 return ret;
1418}
1419
1420/*
1421 * locks that can be taken here:
1422 * dlm->spinlock
1423 * res->spinlock
1424 * mle->spinlock
1425 * dlm->master_list
1426 *
1427 * if possible, TRIM THIS DOWN!!!
1428 */
d74c9803
KH		 1429int dlm_master_request_handler(struct o2net_msg *msg, u32 len, void *data,
1430 void **ret_data)
6714d8e8
KH		 1431{
1432 u8 response = DLM_MASTER_RESP_MAYBE;
1433 struct dlm_ctxt *dlm = data;
9c6510a5 1434 struct dlm_lock_resource *res = NULL;
6714d8e8
KH		 1435 struct dlm_master_request *request = (struct dlm_master_request *) msg->buf;
1436 struct dlm_master_list_entry *mle = NULL, *tmpmle = NULL;
1437 char *name;
a3d33291 1438 unsigned int namelen, hash;
6714d8e8
KH		 1439 int found, ret;
1440 int set_maybe;
9c6510a5 1441 int dispatch_assert = 0;
6714d8e8
KH		 1442
1443 if (!dlm_grab(dlm))
1444 return DLM_MASTER_RESP_NO;
1445
1446 if (!dlm_domain_fully_joined(dlm)) {
1447 response = DLM_MASTER_RESP_NO;
1448 goto send_response;
1449 }
1450
1451 name = request->name;
1452 namelen = request->namelen;
a3d33291 1453 hash = dlm_lockid_hash(name, namelen);
6714d8e8
KH		 1454
1455 if (namelen > DLM_LOCKID_NAME_MAX) {
1456 response = DLM_IVBUFLEN;
1457 goto send_response;
1458 }
1459
1460way_up_top:
1461 spin_lock(&dlm->spinlock);
a3d33291 1462 res = __dlm_lookup_lockres(dlm, name, namelen, hash);
6714d8e8
KH		 1463 if (res) {
1464 spin_unlock(&dlm->spinlock);
1465
1466 /* take care of the easy cases up front */
1467 spin_lock(&res->spinlock);
cb79662b
SE		 1468
1469 /*
1470 * Right after dlm spinlock was released, dlm_thread could have
1471 * purged the lockres. Check if lockres got unhashed. If so
1472 * start over.
1473 */
1474 if (hlist_unhashed(&res->hash_node)) {
1475 spin_unlock(&res->spinlock);
1476 dlm_lockres_put(res);
1477 goto way_up_top;
1478 }
1479
1cd04dbe
KH		 1480 if (res->state & (DLM_LOCK_RES_RECOVERING|
1481 DLM_LOCK_RES_MIGRATING)) {
6714d8e8
KH		 1482 spin_unlock(&res->spinlock);
1483 mlog(0, "returning DLM_MASTER_RESP_ERROR since res is "
1cd04dbe 1484 "being recovered/migrated\n");
6714d8e8
KH		 1485 response = DLM_MASTER_RESP_ERROR;
1486 if (mle)
1487 kmem_cache_free(dlm_mle_cache, mle);
1488 goto send_response;
1489 }
1490
1491 if (res->owner == dlm->node_num) {
8d400b81 1492 dlm_lockres_set_refmap_bit(dlm, res, request->node_idx);
6714d8e8 1493 spin_unlock(&res->spinlock);
6714d8e8
KH		 1494 response = DLM_MASTER_RESP_YES;
1495 if (mle)
1496 kmem_cache_free(dlm_mle_cache, mle);
1497
1498 /* this node is the owner.
1499 * there is some extra work that needs to
1500 * happen now. the requesting node has
1501 * caused all nodes up to this one to
1502 * create mles. this node now needs to
1503 * go back and clean those up. */
9c6510a5 1504 dispatch_assert = 1;
6714d8e8
KH		 1505 goto send_response;
1506 } else if (res->owner != DLM_LOCK_RES_OWNER_UNKNOWN) {
1507 spin_unlock(&res->spinlock);
1508 // mlog(0, "node %u is the master\n", res->owner);
1509 response = DLM_MASTER_RESP_NO;
1510 if (mle)
1511 kmem_cache_free(dlm_mle_cache, mle);
1512 goto send_response;
1513 }
1514
1515 /* ok, there is no owner. either this node is
1516 * being blocked, or it is actively trying to
1517 * master this lock. */
1518 if (!(res->state & DLM_LOCK_RES_IN_PROGRESS)) {
1519 mlog(ML_ERROR, "lock with no owner should be "
1520 "in-progress!\n");
1521 BUG();
1522 }
1523
1524 // mlog(0, "lockres is in progress...\n");
1525 spin_lock(&dlm->master_lock);
1526 found = dlm_find_mle(dlm, &tmpmle, name, namelen);
1527 if (!found) {
1528 mlog(ML_ERROR, "no mle found for this lock!\n");
1529 BUG();
1530 }
1531 set_maybe = 1;
1532 spin_lock(&tmpmle->spinlock);
1533 if (tmpmle->type == DLM_MLE_BLOCK) {
1534 // mlog(0, "this node is waiting for "
1535 // "lockres to be mastered\n");
1536 response = DLM_MASTER_RESP_NO;
1537 } else if (tmpmle->type == DLM_MLE_MIGRATION) {
1538 mlog(0, "node %u is master, but trying to migrate to "
1539 "node %u.\n", tmpmle->master, tmpmle->new_master);
1540 if (tmpmle->master == dlm->node_num) {
6714d8e8
KH		 1541 mlog(ML_ERROR, "no owner on lockres, but this "
1542 "node is trying to migrate it to %u?!\n",
1543 tmpmle->new_master);
1544 BUG();
1545 } else {
1546 /* the real master can respond on its own */
1547 response = DLM_MASTER_RESP_NO;
1548 }
1549 } else if (tmpmle->master != DLM_LOCK_RES_OWNER_UNKNOWN) {
1550 set_maybe = 0;
9c6510a5 1551 if (tmpmle->master == dlm->node_num) {
6714d8e8 1552 response = DLM_MASTER_RESP_YES;
9c6510a5
KH		 1553 /* this node will be the owner.
1554 * go back and clean the mles on any
1555 * other nodes */
1556 dispatch_assert = 1;
8d400b81
SM		 1557 dlm_lockres_set_refmap_bit(dlm, res,
1558 request->node_idx);
9c6510a5 1559 } else
6714d8e8
KH		 1560 response = DLM_MASTER_RESP_NO;
1561 } else {
1562 // mlog(0, "this node is attempting to "
1563 // "master lockres\n");
1564 response = DLM_MASTER_RESP_MAYBE;
1565 }
1566 if (set_maybe)
1567 set_bit(request->node_idx, tmpmle->maybe_map);
1568 spin_unlock(&tmpmle->spinlock);
1569
1570 spin_unlock(&dlm->master_lock);
1571 spin_unlock(&res->spinlock);
1572
1573 /* keep the mle attached to heartbeat events */
1574 dlm_put_mle(tmpmle);
1575 if (mle)
1576 kmem_cache_free(dlm_mle_cache, mle);
1577 goto send_response;
1578 }
1579
1580 /*
1581 * lockres doesn't exist on this node
1582 * if there is an MLE_BLOCK, return NO
1583 * if there is an MLE_MASTER, return MAYBE
1584 * otherwise, add an MLE_BLOCK, return NO
1585 */
1586 spin_lock(&dlm->master_lock);
1587 found = dlm_find_mle(dlm, &tmpmle, name, namelen);
1588 if (!found) {
1589 /* this lockid has never been seen on this node yet */
1590 // mlog(0, "no mle found\n");
1591 if (!mle) {
1592 spin_unlock(&dlm->master_lock);
1593 spin_unlock(&dlm->spinlock);
1594
3914ed0c 1595 mle = kmem_cache_alloc(dlm_mle_cache, GFP_NOFS);
6714d8e8 1596 if (!mle) {
6714d8e8 1597 response = DLM_MASTER_RESP_ERROR;
9c6510a5 1598 mlog_errno(-ENOMEM);
6714d8e8
KH		 1599 goto send_response;
1600 }
6714d8e8
KH		 1601 goto way_up_top;
1602 }
1603
1604 // mlog(0, "this is second time thru, already allocated, "
1605 // "add the block.\n");
41b8c8a1 1606 dlm_init_mle(mle, DLM_MLE_BLOCK, dlm, NULL, name, namelen);
6714d8e8 1607 set_bit(request->node_idx, mle->maybe_map);
1c084577 1608 __dlm_insert_mle(dlm, mle);
6714d8e8
KH		 1609 response = DLM_MASTER_RESP_NO;
1610 } else {
1611 // mlog(0, "mle was found\n");
1612 set_maybe = 1;
1613 spin_lock(&tmpmle->spinlock);
9c6510a5
KH		 1614 if (tmpmle->master == dlm->node_num) {
1615 mlog(ML_ERROR, "no lockres, but an mle with this node as master!\n");
1616 BUG();
1617 }
6714d8e8
KH		 1618 if (tmpmle->type == DLM_MLE_BLOCK)
1619 response = DLM_MASTER_RESP_NO;
1620 else if (tmpmle->type == DLM_MLE_MIGRATION) {
1621 mlog(0, "migration mle was found (%u->%u)\n",
1622 tmpmle->master, tmpmle->new_master);
6714d8e8
KH		 1623 /* real master can respond on its own */
1624 response = DLM_MASTER_RESP_NO;
9c6510a5
KH		 1625 } else
1626 response = DLM_MASTER_RESP_MAYBE;
6714d8e8
KH		 1627 if (set_maybe)
1628 set_bit(request->node_idx, tmpmle->maybe_map);
1629 spin_unlock(&tmpmle->spinlock);
1630 }
1631 spin_unlock(&dlm->master_lock);
1632 spin_unlock(&dlm->spinlock);
1633
1634 if (found) {
1635 /* keep the mle attached to heartbeat events */
1636 dlm_put_mle(tmpmle);
1637 }
1638send_response:
b31cfc02
SM		 1639 /*
1640 * __dlm_lookup_lockres() grabbed a reference to this lockres.
1641 * The reference is released by dlm_assert_master_worker() under
1642 * the call to dlm_dispatch_assert_master(). If
1643 * dlm_assert_master_worker() isn't called, we drop it here.
1644 */
9c6510a5
KH		 1645 if (dispatch_assert) {
1646 if (response != DLM_MASTER_RESP_YES)
1647 mlog(ML_ERROR, "invalid response %d\n", response);
1648 if (!res) {
1649 mlog(ML_ERROR, "bad lockres while trying to assert!\n");
1650 BUG();
1651 }
1652 mlog(0, "%u is the owner of %.*s, cleaning everyone else\n",
1653 dlm->node_num, res->lockname.len, res->lockname.name);
1e589581 1654 spin_lock(&res->spinlock);
2bd63216 1655 ret = dlm_dispatch_assert_master(dlm, res, 0, request->node_idx,
9c6510a5
KH		 1656 DLM_ASSERT_MASTER_MLE_CLEANUP);
1657 if (ret < 0) {
1658 mlog(ML_ERROR, "failed to dispatch assert master work\n");
1659 response = DLM_MASTER_RESP_ERROR;
b31cfc02 1660 dlm_lockres_put(res);
ac4fef4d 1661 } else
1e589581
JQ		 1662 __dlm_lockres_grab_inflight_worker(dlm, res);
1663 spin_unlock(&res->spinlock);
b31cfc02
SM		 1664 } else {
1665 if (res)
1666 dlm_lockres_put(res);
9c6510a5
KH		 1667 }
1668
6714d8e8
KH		 1669 dlm_put(dlm);
1670 return response;
1671}
1672
1673/*
1674 * DLM_ASSERT_MASTER_MSG
1675 */
1676
1677
1678/*
1679 * NOTE: this can be used for debugging
1680 * can periodically run all locks owned by this node
1681 * and re-assert across the cluster...
1682 */
05488bbe
AB		 1683static int dlm_do_assert_master(struct dlm_ctxt *dlm,
1684 struct dlm_lock_resource *res,
1685 void *nodemap, u32 flags)
6714d8e8
KH		 1686{
1687 struct dlm_assert_master assert;
1688 int to, tmpret;
1689 struct dlm_node_iter iter;
1690 int ret = 0;
9c6510a5 1691 int reassert;
ba2bf218
KH		 1692 const char *lockname = res->lockname.name;
1693 unsigned int namelen = res->lockname.len;
6714d8e8
KH		 1694
1695 BUG_ON(namelen > O2NM_MAX_NAME_LEN);
f3f85464
SM		 1696
1697 spin_lock(&res->spinlock);
1698 res->state |= DLM_LOCK_RES_SETREF_INPROG;
1699 spin_unlock(&res->spinlock);
1700
9c6510a5
KH		 1701again:
1702 reassert = 0;
6714d8e8
KH		 1703
1704 /* note that if this nodemap is empty, it returns 0 */
1705 dlm_node_iter_init(nodemap, &iter);
1706 while ((to = dlm_node_iter_next(&iter)) >= 0) {
1707 int r = 0;
a9ee4c8a
KH		 1708 struct dlm_master_list_entry *mle = NULL;
1709
6714d8e8
KH		 1710 mlog(0, "sending assert master to %d (%.*s)\n", to,
1711 namelen, lockname);
1712 memset(&assert, 0, sizeof(assert));
1713 assert.node_idx = dlm->node_num;
1714 assert.namelen = namelen;
1715 memcpy(assert.name, lockname, namelen);
1716 assert.flags = cpu_to_be32(flags);
1717
1718 tmpret = o2net_send_message(DLM_ASSERT_MASTER_MSG, dlm->key,
1719 &assert, sizeof(assert), to, &r);
1720 if (tmpret < 0) {
a5196ec5
WW		 1721 mlog(ML_ERROR, "Error %d when sending message %u (key "
1722 "0x%x) to node %u\n", tmpret,
1723 DLM_ASSERT_MASTER_MSG, dlm->key, to);
6714d8e8 1724 if (!dlm_is_host_down(tmpret)) {
3b3b84a8 1725 mlog(ML_ERROR, "unhandled error=%d!\n", tmpret);
6714d8e8
KH		 1726 BUG();
1727 }
1728 /* a node died. finish out the rest of the nodes. */
3b3b84a8 1729 mlog(0, "link to %d went down!\n", to);
6714d8e8
KH		 1730 /* any nonzero status return will do */
1731 ret = tmpret;
ba2bf218 1732 r = 0;
6714d8e8
KH		 1733 } else if (r < 0) {
1734 /* ok, something horribly messed. kill thyself. */
1735 mlog(ML_ERROR,"during assert master of %.*s to %u, "
1736 "got %d.\n", namelen, lockname, to, r);
a9ee4c8a
KH		 1737 spin_lock(&dlm->spinlock);
1738 spin_lock(&dlm->master_lock);
1739 if (dlm_find_mle(dlm, &mle, (char *)lockname,
1740 namelen)) {
1741 dlm_print_one_mle(mle);
1742 __dlm_put_mle(mle);
1743 }
1744 spin_unlock(&dlm->master_lock);
1745 spin_unlock(&dlm->spinlock);
6714d8e8 1746 BUG();
ba2bf218
KH		 1747 }
1748
1749 if (r & DLM_ASSERT_RESPONSE_REASSERT &&
1750 !(r & DLM_ASSERT_RESPONSE_MASTERY_REF)) {
1751 mlog(ML_ERROR, "%.*s: very strange, "
1752 "master MLE but no lockres on %u\n",
1753 namelen, lockname, to);
1754 }
1755
1756 if (r & DLM_ASSERT_RESPONSE_REASSERT) {
9c6510a5 1757 mlog(0, "%.*s: node %u create mles on other "
2bd63216 1758 "nodes and requests a re-assert\n",
9c6510a5
KH		 1759 namelen, lockname, to);
1760 reassert = 1;
6714d8e8 1761 }
ba2bf218
KH		 1762 if (r & DLM_ASSERT_RESPONSE_MASTERY_REF) {
1763 mlog(0, "%.*s: node %u has a reference to this "
1764 "lockres, set the bit in the refmap\n",
1765 namelen, lockname, to);
1766 spin_lock(&res->spinlock);
8d400b81 1767 dlm_lockres_set_refmap_bit(dlm, res, to);
ba2bf218
KH		 1768 spin_unlock(&res->spinlock);
1769 }
6714d8e8
KH		 1770 }
1771
9c6510a5
KH		 1772 if (reassert)
1773 goto again;
1774
f3f85464
SM		 1775 spin_lock(&res->spinlock);
1776 res->state &= ~DLM_LOCK_RES_SETREF_INPROG;
1777 spin_unlock(&res->spinlock);
1778 wake_up(&res->wq);
1779
6714d8e8
KH		 1780 return ret;
1781}
1782
1783/*
1784 * locks that can be taken here:
1785 * dlm->spinlock
1786 * res->spinlock
1787 * mle->spinlock
1788 * dlm->master_list
1789 *
1790 * if possible, TRIM THIS DOWN!!!
1791 */
d74c9803
KH		 1792int dlm_assert_master_handler(struct o2net_msg *msg, u32 len, void *data,
1793 void **ret_data)
6714d8e8
KH		 1794{
1795 struct dlm_ctxt *dlm = data;
1796 struct dlm_master_list_entry *mle = NULL;
1797 struct dlm_assert_master *assert = (struct dlm_assert_master *)msg->buf;
1798 struct dlm_lock_resource *res = NULL;
1799 char *name;
a3d33291 1800 unsigned int namelen, hash;
6714d8e8 1801 u32 flags;
ba2bf218 1802 int master_request = 0, have_lockres_ref = 0;
9c6510a5 1803 int ret = 0;
6714d8e8
KH		 1804
1805 if (!dlm_grab(dlm))
1806 return 0;
1807
1808 name = assert->name;
1809 namelen = assert->namelen;
a3d33291 1810 hash = dlm_lockid_hash(name, namelen);
6714d8e8
KH		 1811 flags = be32_to_cpu(assert->flags);
1812
1813 if (namelen > DLM_LOCKID_NAME_MAX) {
1814 mlog(ML_ERROR, "Invalid name length!");
1815 goto done;
1816 }
1817
1818 spin_lock(&dlm->spinlock);
1819
1820 if (flags)
1821 mlog(0, "assert_master with flags: %u\n", flags);
1822
1823 /* find the MLE */
1824 spin_lock(&dlm->master_lock);
1825 if (!dlm_find_mle(dlm, &mle, name, namelen)) {
1826 /* not an error, could be master just re-asserting */
1827 mlog(0, "just got an assert_master from %u, but no "
1828 "MLE for it! (%.*s)\n", assert->node_idx,
1829 namelen, name);
1830 } else {
1831 int bit = find_next_bit (mle->maybe_map, O2NM_MAX_NODES, 0);
1832 if (bit >= O2NM_MAX_NODES) {
1833 /* not necessarily an error, though less likely.
1834 * could be master just re-asserting. */
aa852354 1835 mlog(0, "no bits set in the maybe_map, but %u "
6714d8e8
KH		 1836 "is asserting! (%.*s)\n", assert->node_idx,
1837 namelen, name);
1838 } else if (bit != assert->node_idx) {
1839 if (flags & DLM_ASSERT_MASTER_MLE_CLEANUP) {
1840 mlog(0, "master %u was found, %u should "
1841 "back off\n", assert->node_idx, bit);
1842 } else {
1843 /* with the fix for bug 569, a higher node
1844 * number winning the mastery will respond
1845 * YES to mastery requests, but this node
1846 * had no way of knowing. let it pass. */
aa852354 1847 mlog(0, "%u is the lowest node, "
6714d8e8
KH		 1848 "%u is asserting. (%.*s) %u must "
1849 "have begun after %u won.\n", bit,
1850 assert->node_idx, namelen, name, bit,
1851 assert->node_idx);
1852 }
1853 }
2d1a868c
KH		 1854 if (mle->type == DLM_MLE_MIGRATION) {
1855 if (flags & DLM_ASSERT_MASTER_MLE_CLEANUP) {
1856 mlog(0, "%s:%.*s: got cleanup assert"
1857 " from %u for migration\n",
1858 dlm->name, namelen, name,
1859 assert->node_idx);
1860 } else if (!(flags & DLM_ASSERT_MASTER_FINISH_MIGRATION)) {
1861 mlog(0, "%s:%.*s: got unrelated assert"
1862 " from %u for migration, ignoring\n",
1863 dlm->name, namelen, name,
1864 assert->node_idx);
1865 __dlm_put_mle(mle);
1866 spin_unlock(&dlm->master_lock);
1867 spin_unlock(&dlm->spinlock);
1868 goto done;
2bd63216 1869 }
2d1a868c 1870 }
6714d8e8
KH		 1871 }
1872 spin_unlock(&dlm->master_lock);
1873
1874 /* ok everything checks out with the MLE
1875 * now check to see if there is a lockres */
a3d33291 1876 res = __dlm_lookup_lockres(dlm, name, namelen, hash);
6714d8e8
KH		 1877 if (res) {
1878 spin_lock(&res->spinlock);
1879 if (res->state & DLM_LOCK_RES_RECOVERING) {
1880 mlog(ML_ERROR, "%u asserting but %.*s is "
1881 "RECOVERING!\n", assert->node_idx, namelen, name);
1882 goto kill;
1883 }
1884 if (!mle) {
dc2ed195
KH		 1885 if (res->owner != DLM_LOCK_RES_OWNER_UNKNOWN &&
1886 res->owner != assert->node_idx) {
53ecd25e
SM		 1887 mlog(ML_ERROR, "DIE! Mastery assert from %u, "
1888 "but current owner is %u! (%.*s)\n",
1889 assert->node_idx, res->owner, namelen,
1890 name);
1891 __dlm_print_one_lock_resource(res);
1892 BUG();
6714d8e8
KH		 1893 }
1894 } else if (mle->type != DLM_MLE_MIGRATION) {
1895 if (res->owner != DLM_LOCK_RES_OWNER_UNKNOWN) {
1896 /* owner is just re-asserting */
1897 if (res->owner == assert->node_idx) {
1898 mlog(0, "owner %u re-asserting on "
1899 "lock %.*s\n", assert->node_idx,
1900 namelen, name);
1901 goto ok;
1902 }
1903 mlog(ML_ERROR, "got assert_master from "
1904 "node %u, but %u is the owner! "
1905 "(%.*s)\n", assert->node_idx,
1906 res->owner, namelen, name);
1907 goto kill;
1908 }
1909 if (!(res->state & DLM_LOCK_RES_IN_PROGRESS)) {
1910 mlog(ML_ERROR, "got assert from %u, but lock "
1911 "with no owner should be "
1912 "in-progress! (%.*s)\n",
1913 assert->node_idx,
1914 namelen, name);
1915 goto kill;
1916 }
1917 } else /* mle->type == DLM_MLE_MIGRATION */ {
1918 /* should only be getting an assert from new master */
1919 if (assert->node_idx != mle->new_master) {
1920 mlog(ML_ERROR, "got assert from %u, but "
1921 "new master is %u, and old master "
1922 "was %u (%.*s)\n",
1923 assert->node_idx, mle->new_master,
1924 mle->master, namelen, name);
1925 goto kill;
1926 }
1927
1928 }
1929ok:
1930 spin_unlock(&res->spinlock);
1931 }
6714d8e8
KH		 1932
1933 // mlog(0, "woo! got an assert_master from node %u!\n",
1934 // assert->node_idx);
1935 if (mle) {
9c6510a5
KH		 1936 int extra_ref = 0;
1937 int nn = -1;
a2bf0477 1938 int rr, err = 0;
2bd63216 1939
6714d8e8 1940 spin_lock(&mle->spinlock);
9c6510a5
KH		 1941 if (mle->type == DLM_MLE_BLOCK || mle->type == DLM_MLE_MIGRATION)
1942 extra_ref = 1;
1943 else {
1944 /* MASTER mle: if any bits set in the response map
1945 * then the calling node needs to re-assert to clear
1946 * up nodes that this node contacted */
2bd63216 1947 while ((nn = find_next_bit (mle->response_map, O2NM_MAX_NODES,
9c6510a5 1948 nn+1)) < O2NM_MAX_NODES) {
728b9805 1949 if (nn != dlm->node_num && nn != assert->node_idx) {
9c6510a5 1950 master_request = 1;
728b9805
JB		 1951 break;
1952 }
9c6510a5
KH		 1953 }
1954 }
6714d8e8
KH		 1955 mle->master = assert->node_idx;
1956 atomic_set(&mle->woken, 1);
1957 wake_up(&mle->wq);
1958 spin_unlock(&mle->spinlock);
1959
a2bf0477 1960 if (res) {
a6fa3640 1961 int wake = 0;
6714d8e8 1962 spin_lock(&res->spinlock);
a2bf0477
KH		 1963 if (mle->type == DLM_MLE_MIGRATION) {
1964 mlog(0, "finishing off migration of lockres %.*s, "
1965 "from %u to %u\n",
1966 res->lockname.len, res->lockname.name,
1967 dlm->node_num, mle->new_master);
1968 res->state &= ~DLM_LOCK_RES_MIGRATING;
a6fa3640 1969 wake = 1;
a2bf0477
KH		 1970 dlm_change_lockres_owner(dlm, res, mle->new_master);
1971 BUG_ON(res->state & DLM_LOCK_RES_DIRTY);
1972 } else {
1973 dlm_change_lockres_owner(dlm, res, mle->master);
1974 }
6714d8e8 1975 spin_unlock(&res->spinlock);
ba2bf218 1976 have_lockres_ref = 1;
a6fa3640
KH		 1977 if (wake)
1978 wake_up(&res->wq);
6714d8e8 1979 }
a2bf0477
KH		 1980
1981 /* master is known, detach if not already detached.
1982 * ensures that only one assert_master call will happen
1983 * on this mle. */
a2bf0477
KH		 1984 spin_lock(&dlm->master_lock);
1985
1986 rr = atomic_read(&mle->mle_refs.refcount);
1987 if (mle->inuse > 0) {
1988 if (extra_ref && rr < 3)
1989 err = 1;
1990 else if (!extra_ref && rr < 2)
1991 err = 1;
1992 } else {
1993 if (extra_ref && rr < 2)
1994 err = 1;
1995 else if (!extra_ref && rr < 1)
1996 err = 1;
1997 }
1998 if (err) {
1999 mlog(ML_ERROR, "%s:%.*s: got assert master from %u "
2000 "that will mess up this node, refs=%d, extra=%d, "
2001 "inuse=%d\n", dlm->name, namelen, name,
2002 assert->node_idx, rr, extra_ref, mle->inuse);
2003 dlm_print_one_mle(mle);
2004 }
1c084577 2005 __dlm_unlink_mle(dlm, mle);
a2bf0477
KH		 2006 __dlm_mle_detach_hb_events(dlm, mle);
2007 __dlm_put_mle(mle);
6714d8e8
KH		 2008 if (extra_ref) {
2009 /* the assert master message now balances the extra
2010 * ref given by the master / migration request message.
2011 * if this is the last put, it will be removed
2012 * from the list. */
a2bf0477
KH		 2013 __dlm_put_mle(mle);
2014 }
2015 spin_unlock(&dlm->master_lock);
a2bf0477
KH		 2016 } else if (res) {
2017 if (res->owner != assert->node_idx) {
2018 mlog(0, "assert_master from %u, but current "
2019 "owner is %u (%.*s), no mle\n", assert->node_idx,
2020 res->owner, namelen, name);
6714d8e8
KH		 2021 }
2022 }
14741472 2023 spin_unlock(&dlm->spinlock);
6714d8e8
KH		 2024
2025done:
9c6510a5 2026 ret = 0;
3b8118cf
KH		 2027 if (res) {
2028 spin_lock(&res->spinlock);
2029 res->state |= DLM_LOCK_RES_SETREF_INPROG;
2030 spin_unlock(&res->spinlock);
2031 *ret_data = (void *)res;
2032 }
6714d8e8 2033 dlm_put(dlm);
9c6510a5
KH		 2034 if (master_request) {
2035 mlog(0, "need to tell master to reassert\n");
ba2bf218
KH		 2036 /* positive. negative would shoot down the node. */
2037 ret |= DLM_ASSERT_RESPONSE_REASSERT;
2038 if (!have_lockres_ref) {
2039 mlog(ML_ERROR, "strange, got assert from %u, MASTER "
2040 "mle present here for %s:%.*s, but no lockres!\n",
2041 assert->node_idx, dlm->name, namelen, name);
2042 }
2043 }
2044 if (have_lockres_ref) {
2045 /* let the master know we have a reference to the lockres */
2046 ret |= DLM_ASSERT_RESPONSE_MASTERY_REF;
2047 mlog(0, "%s:%.*s: got assert from %u, need a ref\n",
2048 dlm->name, namelen, name, assert->node_idx);
9c6510a5
KH		 2049 }
2050 return ret;
6714d8e8
KH		 2051
2052kill:
2053 /* kill the caller! */
a9ee4c8a
KH		 2054 mlog(ML_ERROR, "Bad message received from another node. Dumping state "
2055 "and killing the other node now! This node is OK and can continue.\n");
2056 __dlm_print_one_lock_resource(res);
6714d8e8 2057 spin_unlock(&res->spinlock);
55dacd22 2058 spin_lock(&dlm->master_lock);
2059 if (mle)
2060 __dlm_put_mle(mle);
2061 spin_unlock(&dlm->master_lock);
6714d8e8 2062 spin_unlock(&dlm->spinlock);
2bd63216 2063 *ret_data = (void *)res;
6714d8e8
KH		 2064 dlm_put(dlm);
2065 return -EINVAL;
2066}
2067
3b8118cf
KH		 2068void dlm_assert_master_post_handler(int status, void *data, void *ret_data)
2069{
2070 struct dlm_lock_resource *res = (struct dlm_lock_resource *)ret_data;
2071
2072 if (ret_data) {
2073 spin_lock(&res->spinlock);
2074 res->state &= ~DLM_LOCK_RES_SETREF_INPROG;
2075 spin_unlock(&res->spinlock);
2076 wake_up(&res->wq);
2077 dlm_lockres_put(res);
2078 }
2079 return;
2080}
2081
6714d8e8
KH		 2082int dlm_dispatch_assert_master(struct dlm_ctxt *dlm,
2083 struct dlm_lock_resource *res,
2084 int ignore_higher, u8 request_from, u32 flags)
2085{
2086 struct dlm_work_item *item;
b24ae0b5 2087 item = kzalloc(sizeof(*item), GFP_ATOMIC);
6714d8e8
KH		 2088 if (!item)
2089 return -ENOMEM;
2090
2091
2092 /* queue up work for dlm_assert_master_worker */
2093 dlm_grab(dlm); /* get an extra ref for the work item */
2094 dlm_init_work_item(dlm, item, dlm_assert_master_worker, NULL);
2095 item->u.am.lockres = res; /* already have a ref */
2096 /* can optionally ignore node numbers higher than this node */
2097 item->u.am.ignore_higher = ignore_higher;
2098 item->u.am.request_from = request_from;
2099 item->u.am.flags = flags;
2100
2bd63216
SM		 2101 if (ignore_higher)
2102 mlog(0, "IGNORE HIGHER: %.*s\n", res->lockname.len,
9c6510a5 2103 res->lockname.name);
2bd63216 2104
6714d8e8
KH		 2105 spin_lock(&dlm->work_lock);
2106 list_add_tail(&item->list, &dlm->work_list);
2107 spin_unlock(&dlm->work_lock);
2108
3156d267 2109 queue_work(dlm->dlm_worker, &dlm->dispatched_work);
6714d8e8
KH		 2110 return 0;
2111}
2112
2113static void dlm_assert_master_worker(struct dlm_work_item *item, void *data)
2114{
2115 struct dlm_ctxt *dlm = data;
2116 int ret = 0;
2117 struct dlm_lock_resource *res;
2118 unsigned long nodemap[BITS_TO_LONGS(O2NM_MAX_NODES)];
2119 int ignore_higher;
2120 int bit;
2121 u8 request_from;
2122 u32 flags;
2123
2124 dlm = item->dlm;
2125 res = item->u.am.lockres;
2126 ignore_higher = item->u.am.ignore_higher;
2127 request_from = item->u.am.request_from;
2128 flags = item->u.am.flags;
2129
2130 spin_lock(&dlm->spinlock);
2131 memcpy(nodemap, dlm->domain_map, sizeof(nodemap));
2132 spin_unlock(&dlm->spinlock);
2133
2134 clear_bit(dlm->node_num, nodemap);
2135 if (ignore_higher) {
2136 /* if is this just to clear up mles for nodes below
2137 * this node, do not send the message to the original
2138 * caller or any node number higher than this */
2139 clear_bit(request_from, nodemap);
2140 bit = dlm->node_num;
2141 while (1) {
2142 bit = find_next_bit(nodemap, O2NM_MAX_NODES,
2143 bit+1);
2144 if (bit >= O2NM_MAX_NODES)
2145 break;
2146 clear_bit(bit, nodemap);
2147 }
2148 }
2149
36407488
KH		 2150 /*
2151 * If we're migrating this lock to someone else, we are no
2152 * longer allowed to assert out own mastery. OTOH, we need to
2153 * prevent migration from starting while we're still asserting
2154 * our dominance. The reserved ast delays migration.
2155 */
2156 spin_lock(&res->spinlock);
2157 if (res->state & DLM_LOCK_RES_MIGRATING) {
2158 mlog(0, "Someone asked us to assert mastery, but we're "
2159 "in the middle of migration. Skipping assert, "
2160 "the new master will handle that.\n");
2161 spin_unlock(&res->spinlock);
2162 goto put;
2163 } else
2164 __dlm_lockres_reserve_ast(res);
2165 spin_unlock(&res->spinlock);
2166
6714d8e8
KH		 2167 /* this call now finishes out the nodemap
2168 * even if one or more nodes die */
2169 mlog(0, "worker about to master %.*s here, this=%u\n",
2170 res->lockname.len, res->lockname.name, dlm->node_num);
ba2bf218 2171 ret = dlm_do_assert_master(dlm, res, nodemap, flags);
6714d8e8
KH		 2172 if (ret < 0) {
2173 /* no need to restart, we are done */
3b3b84a8
KH		 2174 if (!dlm_is_host_down(ret))
2175 mlog_errno(ret);
6714d8e8
KH		 2176 }
2177
36407488
KH		 2178 /* Ok, we've asserted ourselves. Let's let migration start. */
2179 dlm_lockres_release_ast(dlm, res);
2180
2181put:
ac4fef4d
X		 2182 dlm_lockres_drop_inflight_worker(dlm, res);
2183
6714d8e8
KH		 2184 dlm_lockres_put(res);
2185
2186 mlog(0, "finished with dlm_assert_master_worker\n");
2187}
2188
c03872f5
KH		 2189/* SPECIAL CASE for the $RECOVERY lock used by the recovery thread.
2190 * We cannot wait for node recovery to complete to begin mastering this
2191 * lockres because this lockres is used to kick off recovery! ;-)
2192 * So, do a pre-check on all living nodes to see if any of those nodes
2193 * think that $RECOVERY is currently mastered by a dead node. If so,
2194 * we wait a short time to allow that node to get notified by its own
2195 * heartbeat stack, then check again. All $RECOVERY lock resources
2bd63216 2196 * mastered by dead nodes are purged when the hearbeat callback is
c03872f5
KH		 2197 * fired, so we can know for sure that it is safe to continue once
2198 * the node returns a live node or no node. */
2199static int dlm_pre_master_reco_lockres(struct dlm_ctxt *dlm,
2200 struct dlm_lock_resource *res)
2201{
2202 struct dlm_node_iter iter;
2203 int nodenum;
2204 int ret = 0;
2205 u8 master = DLM_LOCK_RES_OWNER_UNKNOWN;
2206
2207 spin_lock(&dlm->spinlock);
2208 dlm_node_iter_init(dlm->domain_map, &iter);
2209 spin_unlock(&dlm->spinlock);
2210
2211 while ((nodenum = dlm_node_iter_next(&iter)) >= 0) {
2212 /* do not send to self */
2213 if (nodenum == dlm->node_num)
2214 continue;
2215 ret = dlm_do_master_requery(dlm, res, nodenum, &master);
2216 if (ret < 0) {
2217 mlog_errno(ret);
2218 if (!dlm_is_host_down(ret))
2219 BUG();
2220 /* host is down, so answer for that node would be
2221 * DLM_LOCK_RES_OWNER_UNKNOWN. continue. */
f42a100b 2222 ret = 0;
c03872f5
KH		 2223 }
2224
2225 if (master != DLM_LOCK_RES_OWNER_UNKNOWN) {
2226 /* check to see if this master is in the recovery map */
2227 spin_lock(&dlm->spinlock);
2228 if (test_bit(master, dlm->recovery_map)) {
2229 mlog(ML_NOTICE, "%s: node %u has not seen "
2230 "node %u go down yet, and thinks the "
2231 "dead node is mastering the recovery "
2232 "lock. must wait.\n", dlm->name,
2233 nodenum, master);
2234 ret = -EAGAIN;
2235 }
2236 spin_unlock(&dlm->spinlock);
2bd63216 2237 mlog(0, "%s: reco lock master is %u\n", dlm->name,
c03872f5
KH		 2238 master);
2239 break;
2240 }
2241 }
2242 return ret;
2243}
2244
ba2bf218
KH		 2245/*
2246 * DLM_DEREF_LOCKRES_MSG
2247 */
2248
2249int dlm_drop_lockres_ref(struct dlm_ctxt *dlm, struct dlm_lock_resource *res)
2250{
2251 struct dlm_deref_lockres deref;
2252 int ret = 0, r;
2253 const char *lockname;
2254 unsigned int namelen;
2255
2256 lockname = res->lockname.name;
2257 namelen = res->lockname.len;
2258 BUG_ON(namelen > O2NM_MAX_NAME_LEN);
2259
ba2bf218
KH		 2260 memset(&deref, 0, sizeof(deref));
2261 deref.node_idx = dlm->node_num;
2262 deref.namelen = namelen;
2263 memcpy(deref.name, lockname, namelen);
2264
2265 ret = o2net_send_message(DLM_DEREF_LOCKRES_MSG, dlm->key,
2266 &deref, sizeof(deref), res->owner, &r);
2267 if (ret < 0)
8decab3c
SM		 2268 mlog(ML_ERROR, "%s: res %.*s, error %d send DEREF to node %u\n",
2269 dlm->name, namelen, lockname, ret, res->owner);
ba2bf218
KH		 2270 else if (r < 0) {
2271 /* BAD. other node says I did not have a ref. */
8decab3c
SM		 2272 mlog(ML_ERROR, "%s: res %.*s, DEREF to node %u got %d\n",
2273 dlm->name, namelen, lockname, res->owner, r);
ba2bf218
KH		 2274 dlm_print_one_lock_resource(res);
2275 BUG();
2276 }
2277 return ret;
2278}
2279
d74c9803
KH		 2280int dlm_deref_lockres_handler(struct o2net_msg *msg, u32 len, void *data,
2281 void **ret_data)
ba2bf218
KH		 2282{
2283 struct dlm_ctxt *dlm = data;
2284 struct dlm_deref_lockres *deref = (struct dlm_deref_lockres *)msg->buf;
2285 struct dlm_lock_resource *res = NULL;
2286 char *name;
2287 unsigned int namelen;
2288 int ret = -EINVAL;
2289 u8 node;
2290 unsigned int hash;
f3f85464
SM		 2291 struct dlm_work_item *item;
2292 int cleared = 0;
2293 int dispatch = 0;
ba2bf218
KH		 2294
2295 if (!dlm_grab(dlm))
2296 return 0;
2297
2298 name = deref->name;
2299 namelen = deref->namelen;
2300 node = deref->node_idx;
2301
2302 if (namelen > DLM_LOCKID_NAME_MAX) {
2303 mlog(ML_ERROR, "Invalid name length!");
2304 goto done;
2305 }
2306 if (deref->node_idx >= O2NM_MAX_NODES) {
2307 mlog(ML_ERROR, "Invalid node number: %u\n", node);
2308 goto done;
2309 }
2310
2311 hash = dlm_lockid_hash(name, namelen);
2312
2313 spin_lock(&dlm->spinlock);
2314 res = __dlm_lookup_lockres_full(dlm, name, namelen, hash);
2315 if (!res) {
2316 spin_unlock(&dlm->spinlock);
2317 mlog(ML_ERROR, "%s:%.*s: bad lockres name\n",
2318 dlm->name, namelen, name);
2319 goto done;
2320 }
2321 spin_unlock(&dlm->spinlock);
2322
2323 spin_lock(&res->spinlock);
f3f85464
SM		 2324 if (res->state & DLM_LOCK_RES_SETREF_INPROG)
2325 dispatch = 1;
2326 else {
2327 BUG_ON(res->state & DLM_LOCK_RES_DROPPING_REF);
2328 if (test_bit(node, res->refmap)) {
8d400b81 2329 dlm_lockres_clear_refmap_bit(dlm, res, node);
f3f85464
SM		 2330 cleared = 1;
2331 }
ba2bf218
KH		 2332 }
2333 spin_unlock(&res->spinlock);
2334
f3f85464
SM		 2335 if (!dispatch) {
2336 if (cleared)
2337 dlm_lockres_calc_usage(dlm, res);
2338 else {
2339 mlog(ML_ERROR, "%s:%.*s: node %u trying to drop ref "
2340 "but it is already dropped!\n", dlm->name,
2341 res->lockname.len, res->lockname.name, node);
2af37ce8 2342 dlm_print_one_lock_resource(res);
f3f85464
SM		 2343 }
2344 ret = 0;
2345 goto done;
2346 }
2347
2348 item = kzalloc(sizeof(*item), GFP_NOFS);
2349 if (!item) {
2350 ret = -ENOMEM;
2351 mlog_errno(ret);
2352 goto done;
2353 }
2354
2355 dlm_init_work_item(dlm, item, dlm_deref_lockres_worker, NULL);
2356 item->u.dl.deref_res = res;
2357 item->u.dl.deref_node = node;
2358
2359 spin_lock(&dlm->work_lock);
2360 list_add_tail(&item->list, &dlm->work_list);
2361 spin_unlock(&dlm->work_lock);
2362
2363 queue_work(dlm->dlm_worker, &dlm->dispatched_work);
2364 return 0;
2365
ba2bf218
KH		 2366done:
2367 if (res)
2368 dlm_lockres_put(res);
2369 dlm_put(dlm);
f3f85464 2370
ba2bf218
KH		 2371 return ret;
2372}
2373
f3f85464
SM		 2374static void dlm_deref_lockres_worker(struct dlm_work_item *item, void *data)
2375{
2376 struct dlm_ctxt *dlm;
2377 struct dlm_lock_resource *res;
2378 u8 node;
2379 u8 cleared = 0;
2380
2381 dlm = item->dlm;
2382 res = item->u.dl.deref_res;
2383 node = item->u.dl.deref_node;
2384
2385 spin_lock(&res->spinlock);
2386 BUG_ON(res->state & DLM_LOCK_RES_DROPPING_REF);
2387 if (test_bit(node, res->refmap)) {
2388 __dlm_wait_on_lockres_flags(res, DLM_LOCK_RES_SETREF_INPROG);
8d400b81 2389 dlm_lockres_clear_refmap_bit(dlm, res, node);
f3f85464
SM		 2390 cleared = 1;
2391 }
2392 spin_unlock(&res->spinlock);
2393
2394 if (cleared) {
2395 mlog(0, "%s:%.*s node %u ref dropped in dispatch\n",
2396 dlm->name, res->lockname.len, res->lockname.name, node);
2397 dlm_lockres_calc_usage(dlm, res);
2398 } else {
2399 mlog(ML_ERROR, "%s:%.*s: node %u trying to drop ref "
2400 "but it is already dropped!\n", dlm->name,
2401 res->lockname.len, res->lockname.name, node);
2af37ce8 2402 dlm_print_one_lock_resource(res);
f3f85464
SM		 2403 }
2404
2405 dlm_lockres_put(res);
2406}
2407
9f62e960
SM		 2408/*
2409 * A migrateable resource is one that is :
2410 * 1. locally mastered, and,
2411 * 2. zero local locks, and,
2412 * 3. one or more non-local locks, or, one or more references
2413 * Returns 1 if yes, 0 if not.
2f5bf1f2
SM		 2414 */
2415static int dlm_is_lockres_migrateable(struct dlm_ctxt *dlm,
9f62e960 2416 struct dlm_lock_resource *res)
2f5bf1f2 2417{
9f62e960
SM		 2418 enum dlm_lockres_list idx;
2419 int nonlocal = 0, node_ref;
800deef3 2420 struct list_head *queue;
2f5bf1f2 2421 struct dlm_lock *lock;
9f62e960 2422 u64 cookie;
2f5bf1f2
SM		 2423
2424 assert_spin_locked(&res->spinlock);
2425
fae477b6
X		 2426 /* delay migration when the lockres is in MIGRATING state */
2427 if (res->state & DLM_LOCK_RES_MIGRATING)
2428 return 0;
2429
bba1cb17
TS		 2430 /* delay migration when the lockres is in RECOCERING state */
2431 if (res->state & DLM_LOCK_RES_RECOVERING)
2432 return 0;
2433
9f62e960
SM		 2434 if (res->owner != dlm->node_num)
2435 return 0;
2f5bf1f2 2436
9f62e960
SM		 2437 for (idx = DLM_GRANTED_LIST; idx <= DLM_BLOCKED_LIST; idx++) {
2438 queue = dlm_list_idx_to_ptr(res, idx);
800deef3 2439 list_for_each_entry(lock, queue, list) {
9f62e960
SM		 2440 if (lock->ml.node != dlm->node_num) {
2441 nonlocal++;
2442 continue;
2f5bf1f2 2443 }
9f62e960
SM		 2444 cookie = be64_to_cpu(lock->ml.cookie);
2445 mlog(0, "%s: Not migrateable res %.*s, lock %u:%llu on "
2446 "%s list\n", dlm->name, res->lockname.len,
2447 res->lockname.name,
2448 dlm_get_lock_cookie_node(cookie),
2449 dlm_get_lock_cookie_seq(cookie),
2450 dlm_list_in_text(idx));
2451 return 0;
2f5bf1f2 2452 }
2f5bf1f2
SM		 2453 }
2454
9f62e960
SM		 2455 if (!nonlocal) {
2456 node_ref = find_next_bit(res->refmap, O2NM_MAX_NODES, 0);
2457 if (node_ref >= O2NM_MAX_NODES)
2458 return 0;
2459 }
388c4bcb 2460
9f62e960
SM		 2461 mlog(0, "%s: res %.*s, Migrateable\n", dlm->name, res->lockname.len,
2462 res->lockname.name);
2f5bf1f2 2463
9f62e960 2464 return 1;
2f5bf1f2 2465}
6714d8e8
KH		 2466
2467/*
2468 * DLM_MIGRATE_LOCKRES
2469 */
2470
2471
faf0ec9f 2472static int dlm_migrate_lockres(struct dlm_ctxt *dlm,
66effd3c 2473 struct dlm_lock_resource *res, u8 target)
6714d8e8
KH		 2474{
2475 struct dlm_master_list_entry *mle = NULL;
2476 struct dlm_master_list_entry *oldmle = NULL;
2477 struct dlm_migratable_lockres *mres = NULL;
2f5bf1f2 2478 int ret = 0;
6714d8e8
KH		 2479 const char *name;
2480 unsigned int namelen;
2481 int mle_added = 0;
2f5bf1f2 2482 int wake = 0;
6714d8e8
KH		 2483
2484 if (!dlm_grab(dlm))
2485 return -EINVAL;
2486
66effd3c
SM		 2487 BUG_ON(target == O2NM_MAX_NODES);
2488
6714d8e8
KH		 2489 name = res->lockname.name;
2490 namelen = res->lockname.len;
2491
66effd3c
SM		 2492 mlog(0, "%s: Migrating %.*s to node %u\n", dlm->name, namelen, name,
2493 target);
6714d8e8 2494
66effd3c 2495 /* preallocate up front. if this fails, abort */
6714d8e8 2496 ret = -ENOMEM;
ad8100e0 2497 mres = (struct dlm_migratable_lockres *) __get_free_page(GFP_NOFS);
6714d8e8
KH		 2498 if (!mres) {
2499 mlog_errno(ret);
2500 goto leave;
2501 }
2502
3914ed0c 2503 mle = kmem_cache_alloc(dlm_mle_cache, GFP_NOFS);
6714d8e8
KH		 2504 if (!mle) {
2505 mlog_errno(ret);
2506 goto leave;
2507 }
2508 ret = 0;
2509
6714d8e8
KH		 2510 /*
2511 * clear any existing master requests and
2512 * add the migration mle to the list
2513 */
66effd3c 2514 spin_lock(&dlm->spinlock);
6714d8e8
KH		 2515 spin_lock(&dlm->master_lock);
2516 ret = dlm_add_migration_mle(dlm, res, mle, &oldmle, name,
2517 namelen, target, dlm->node_num);
2518 spin_unlock(&dlm->master_lock);
2519 spin_unlock(&dlm->spinlock);
2520
2521 if (ret == -EEXIST) {
2522 mlog(0, "another process is already migrating it\n");
2523 goto fail;
2524 }
2525 mle_added = 1;
2526
2527 /*
2528 * set the MIGRATING flag and flush asts
2529 * if we fail after this we need to re-dirty the lockres
2530 */
2531 if (dlm_mark_lockres_migrating(dlm, res, target) < 0) {
2532 mlog(ML_ERROR, "tried to migrate %.*s to %u, but "
2533 "the target went down.\n", res->lockname.len,
2534 res->lockname.name, target);
2535 spin_lock(&res->spinlock);
2536 res->state &= ~DLM_LOCK_RES_MIGRATING;
a6fa3640 2537 wake = 1;
6714d8e8
KH		 2538 spin_unlock(&res->spinlock);
2539 ret = -EINVAL;
2540 }
2541
2542fail:
2543 if (oldmle) {
2544 /* master is known, detach if not already detached */
2545 dlm_mle_detach_hb_events(dlm, oldmle);
2546 dlm_put_mle(oldmle);
2547 }
2548
2549 if (ret < 0) {
2550 if (mle_added) {
2551 dlm_mle_detach_hb_events(dlm, mle);
2552 dlm_put_mle(mle);
2553 } else if (mle) {
2554 kmem_cache_free(dlm_mle_cache, mle);
66effd3c 2555 mle = NULL;
6714d8e8
KH		 2556 }
2557 goto leave;
2558 }
2559
2560 /*
2561 * at this point, we have a migration target, an mle
2562 * in the master list, and the MIGRATING flag set on
2563 * the lockres
2564 */
2565
1cd04dbe
KH		 2566 /* now that remote nodes are spinning on the MIGRATING flag,
2567 * ensure that all assert_master work is flushed. */
2568 flush_workqueue(dlm->dlm_worker);
6714d8e8
KH		 2569
2570 /* get an extra reference on the mle.
2571 * otherwise the assert_master from the new
2572 * master will destroy this.
2573 * also, make sure that all callers of dlm_get_mle
2574 * take both dlm->spinlock and dlm->master_lock */
2575 spin_lock(&dlm->spinlock);
2576 spin_lock(&dlm->master_lock);
a2bf0477 2577 dlm_get_mle_inuse(mle);
6714d8e8
KH		 2578 spin_unlock(&dlm->master_lock);
2579 spin_unlock(&dlm->spinlock);
2580
2581 /* notify new node and send all lock state */
2582 /* call send_one_lockres with migration flag.
2583 * this serves as notice to the target node that a
2584 * migration is starting. */
2585 ret = dlm_send_one_lockres(dlm, res, mres, target,
2586 DLM_MRES_MIGRATION);
2587
2588 if (ret < 0) {
2589 mlog(0, "migration to node %u failed with %d\n",
2590 target, ret);
2591 /* migration failed, detach and clean up mle */
2592 dlm_mle_detach_hb_events(dlm, mle);
2593 dlm_put_mle(mle);
a2bf0477
KH		 2594 dlm_put_mle_inuse(mle);
2595 spin_lock(&res->spinlock);
2596 res->state &= ~DLM_LOCK_RES_MIGRATING;
a6fa3640 2597 wake = 1;
a2bf0477 2598 spin_unlock(&res->spinlock);
df016c66
SM		 2599 if (dlm_is_host_down(ret))
2600 dlm_wait_for_node_death(dlm, target,
2601 DLM_NODE_DEATH_WAIT_MAX);
6714d8e8
KH		 2602 goto leave;
2603 }
2604
2605 /* at this point, the target sends a message to all nodes,
2606 * (using dlm_do_migrate_request). this node is skipped since
2607 * we had to put an mle in the list to begin the process. this
2608 * node now waits for target to do an assert master. this node
2609 * will be the last one notified, ensuring that the migration
2610 * is complete everywhere. if the target dies while this is
2611 * going on, some nodes could potentially see the target as the
2612 * master, so it is important that my recovery finds the migration
af901ca1 2613 * mle and sets the master to UNKNOWN. */
6714d8e8
KH		 2614
2615
2616 /* wait for new node to assert master */
2617 while (1) {
2618 ret = wait_event_interruptible_timeout(mle->wq,
2619 (atomic_read(&mle->woken) == 1),
2620 msecs_to_jiffies(5000));
2621
2622 if (ret >= 0) {
2623 if (atomic_read(&mle->woken) == 1 ||
2624 res->owner == target)
2625 break;
2626
1cd04dbe
KH		 2627 mlog(0, "%s:%.*s: timed out during migration\n",
2628 dlm->name, res->lockname.len, res->lockname.name);
2bd63216 2629 /* avoid hang during shutdown when migrating lockres
e2faea4c
KH		 2630 * to a node which also goes down */
2631 if (dlm_is_node_dead(dlm, target)) {
aa852354
KH		 2632 mlog(0, "%s:%.*s: expected migration "
2633 "target %u is no longer up, restarting\n",
e2faea4c
KH		 2634 dlm->name, res->lockname.len,
2635 res->lockname.name, target);
1cd04dbe
KH		 2636 ret = -EINVAL;
2637 /* migration failed, detach and clean up mle */
2638 dlm_mle_detach_hb_events(dlm, mle);
2639 dlm_put_mle(mle);
2640 dlm_put_mle_inuse(mle);
2641 spin_lock(&res->spinlock);
2642 res->state &= ~DLM_LOCK_RES_MIGRATING;
a6fa3640 2643 wake = 1;
1cd04dbe
KH		 2644 spin_unlock(&res->spinlock);
2645 goto leave;
e2faea4c 2646 }
1cd04dbe
KH		 2647 } else
2648 mlog(0, "%s:%.*s: caught signal during migration\n",
2649 dlm->name, res->lockname.len, res->lockname.name);
6714d8e8
KH		 2650 }
2651
2652 /* all done, set the owner, clear the flag */
2653 spin_lock(&res->spinlock);
2654 dlm_set_lockres_owner(dlm, res, target);
2655 res->state &= ~DLM_LOCK_RES_MIGRATING;
2656 dlm_remove_nonlocal_locks(dlm, res);
2657 spin_unlock(&res->spinlock);
2658 wake_up(&res->wq);
2659
2660 /* master is known, detach if not already detached */
2661 dlm_mle_detach_hb_events(dlm, mle);
a2bf0477 2662 dlm_put_mle_inuse(mle);
6714d8e8
KH		 2663 ret = 0;
2664
2665 dlm_lockres_calc_usage(dlm, res);
2666
2667leave:
2668 /* re-dirty the lockres if we failed */
2669 if (ret < 0)
2670 dlm_kick_thread(dlm, res);
2671
a6fa3640
KH		 2672 /* wake up waiters if the MIGRATING flag got set
2673 * but migration failed */
2674 if (wake)
2675 wake_up(&res->wq);
2676
6714d8e8
KH		 2677 if (mres)
2678 free_page((unsigned long)mres);
2679
2680 dlm_put(dlm);
2681
9f62e960
SM		 2682 mlog(0, "%s: Migrating %.*s to %u, returns %d\n", dlm->name, namelen,
2683 name, target, ret);
6714d8e8
KH		 2684 return ret;
2685}
6714d8e8 2686
ba2bf218
KH		 2687#define DLM_MIGRATION_RETRY_MS 100
2688
9f62e960
SM		 2689/*
2690 * Should be called only after beginning the domain leave process.
ba2bf218
KH		 2691 * There should not be any remaining locks on nonlocal lock resources,
2692 * and there should be no local locks left on locally mastered resources.
2693 *
2694 * Called with the dlm spinlock held, may drop it to do migration, but
2695 * will re-acquire before exit.
2696 *
9f62e960
SM		 2697 * Returns: 1 if dlm->spinlock was dropped/retaken, 0 if never dropped
2698 */
ba2bf218
KH		 2699int dlm_empty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res)
2700{
66effd3c 2701 int ret;
ba2bf218 2702 int lock_dropped = 0;
66effd3c 2703 u8 target = O2NM_MAX_NODES;
ba2bf218 2704
9f62e960 2705 assert_spin_locked(&dlm->spinlock);
2f5bf1f2 2706
9f62e960 2707 spin_lock(&res->spinlock);
66effd3c
SM		 2708 if (dlm_is_lockres_migrateable(dlm, res))
2709 target = dlm_pick_migration_target(dlm, res);
b36c3f84 2710 spin_unlock(&res->spinlock);
66effd3c
SM		 2711
2712 if (target == O2NM_MAX_NODES)
9f62e960 2713 goto leave;
ba2bf218
KH		 2714
2715 /* Wheee! Migrate lockres here! Will sleep so drop spinlock. */
2716 spin_unlock(&dlm->spinlock);
2717 lock_dropped = 1;
66effd3c
SM		 2718 ret = dlm_migrate_lockres(dlm, res, target);
2719 if (ret)
2720 mlog(0, "%s: res %.*s, Migrate to node %u failed with %d\n",
2721 dlm->name, res->lockname.len, res->lockname.name,
2722 target, ret);
ba2bf218
KH		 2723 spin_lock(&dlm->spinlock);
2724leave:
2725 return lock_dropped;
2726}
2727
6714d8e8
KH		 2728int dlm_lock_basts_flushed(struct dlm_ctxt *dlm, struct dlm_lock *lock)
2729{
2730 int ret;
2731 spin_lock(&dlm->ast_lock);
2732 spin_lock(&lock->spinlock);
2733 ret = (list_empty(&lock->bast_list) && !lock->bast_pending);
2734 spin_unlock(&lock->spinlock);
2735 spin_unlock(&dlm->ast_lock);
2736 return ret;
2737}
2738
2739static int dlm_migration_can_proceed(struct dlm_ctxt *dlm,
2740 struct dlm_lock_resource *res,
2741 u8 mig_target)
2742{
2743 int can_proceed;
2744 spin_lock(&res->spinlock);
2745 can_proceed = !!(res->state & DLM_LOCK_RES_MIGRATING);
2746 spin_unlock(&res->spinlock);
2747
2bd63216 2748 /* target has died, so make the caller break out of the
6714d8e8
KH		 2749 * wait_event, but caller must recheck the domain_map */
2750 spin_lock(&dlm->spinlock);
2751 if (!test_bit(mig_target, dlm->domain_map))
2752 can_proceed = 1;
2753 spin_unlock(&dlm->spinlock);
2754 return can_proceed;
2755}
2756
faf0ec9f
AB		 2757static int dlm_lockres_is_dirty(struct dlm_ctxt *dlm,
2758 struct dlm_lock_resource *res)
6714d8e8
KH		 2759{
2760 int ret;
2761 spin_lock(&res->spinlock);
2762 ret = !!(res->state & DLM_LOCK_RES_DIRTY);
2763 spin_unlock(&res->spinlock);
2764 return ret;
2765}
2766
2767
2768static int dlm_mark_lockres_migrating(struct dlm_ctxt *dlm,
2769 struct dlm_lock_resource *res,
2770 u8 target)
2771{
2772 int ret = 0;
2773
2774 mlog(0, "dlm_mark_lockres_migrating: %.*s, from %u to %u\n",
2775 res->lockname.len, res->lockname.name, dlm->node_num,
2776 target);
2777 /* need to set MIGRATING flag on lockres. this is done by
2778 * ensuring that all asts have been flushed for this lockres. */
2779 spin_lock(&res->spinlock);
2780 BUG_ON(res->migration_pending);
2781 res->migration_pending = 1;
2782 /* strategy is to reserve an extra ast then release
2783 * it below, letting the release do all of the work */
2784 __dlm_lockres_reserve_ast(res);
2785 spin_unlock(&res->spinlock);
2786
ddc09c8d 2787 /* now flush all the pending asts */
6714d8e8 2788 dlm_kick_thread(dlm, res);
ddc09c8d
KH		 2789 /* before waiting on DIRTY, block processes which may
2790 * try to dirty the lockres before MIGRATING is set */
2791 spin_lock(&res->spinlock);
2792 BUG_ON(res->state & DLM_LOCK_RES_BLOCK_DIRTY);
2793 res->state |= DLM_LOCK_RES_BLOCK_DIRTY;
2794 spin_unlock(&res->spinlock);
2795 /* now wait on any pending asts and the DIRTY state */
6714d8e8
KH		 2796 wait_event(dlm->ast_wq, !dlm_lockres_is_dirty(dlm, res));
2797 dlm_lockres_release_ast(dlm, res);
2798
2799 mlog(0, "about to wait on migration_wq, dirty=%s\n",
2800 res->state & DLM_LOCK_RES_DIRTY ? "yes" : "no");
2801 /* if the extra ref we just put was the final one, this
2802 * will pass thru immediately. otherwise, we need to wait
2803 * for the last ast to finish. */
2804again:
2805 ret = wait_event_interruptible_timeout(dlm->migration_wq,
2806 dlm_migration_can_proceed(dlm, res, target),
2807 msecs_to_jiffies(1000));
2808 if (ret < 0) {
2809 mlog(0, "woken again: migrating? %s, dead? %s\n",
2810 res->state & DLM_LOCK_RES_MIGRATING ? "yes":"no",
2811 test_bit(target, dlm->domain_map) ? "no":"yes");
2812 } else {
2813 mlog(0, "all is well: migrating? %s, dead? %s\n",
2814 res->state & DLM_LOCK_RES_MIGRATING ? "yes":"no",
2815 test_bit(target, dlm->domain_map) ? "no":"yes");
2816 }
2817 if (!dlm_migration_can_proceed(dlm, res, target)) {
2818 mlog(0, "trying again...\n");
2819 goto again;
2820 }
2821
a39953dd 2822 ret = 0;
6714d8e8
KH		 2823 /* did the target go down or die? */
2824 spin_lock(&dlm->spinlock);
2825 if (!test_bit(target, dlm->domain_map)) {
2826 mlog(ML_ERROR, "aha. migration target %u just went down\n",
2827 target);
2828 ret = -EHOSTDOWN;
2829 }
2830 spin_unlock(&dlm->spinlock);
2831
a39953dd
WW		 2832 /*
2833 * if target is down, we need to clear DLM_LOCK_RES_BLOCK_DIRTY for
2834 * another try; otherwise, we are sure the MIGRATING state is there,
2835 * drop the unneded state which blocked threads trying to DIRTY
2836 */
2837 spin_lock(&res->spinlock);
2838 BUG_ON(!(res->state & DLM_LOCK_RES_BLOCK_DIRTY));
2839 res->state &= ~DLM_LOCK_RES_BLOCK_DIRTY;
2840 if (!ret)
2841 BUG_ON(!(res->state & DLM_LOCK_RES_MIGRATING));
2842 spin_unlock(&res->spinlock);
2843
6714d8e8
KH		 2844 /*
2845 * at this point:
2846 *
a39953dd 2847 * o the DLM_LOCK_RES_MIGRATING flag is set if target not down
6714d8e8
KH		 2848 * o there are no pending asts on this lockres
2849 * o all processes trying to reserve an ast on this
2850 * lockres must wait for the MIGRATING flag to clear
2851 */
2852 return ret;
2853}
2854
2855/* last step in the migration process.
2856 * original master calls this to free all of the dlm_lock
2857 * structures that used to be for other nodes. */
2858static void dlm_remove_nonlocal_locks(struct dlm_ctxt *dlm,
2859 struct dlm_lock_resource *res)
2860{
6714d8e8 2861 struct list_head *queue = &res->granted;
ba2bf218 2862 int i, bit;
800deef3 2863 struct dlm_lock *lock, *next;
6714d8e8
KH		 2864
2865 assert_spin_locked(&res->spinlock);
2866
2867 BUG_ON(res->owner == dlm->node_num);
2868
2869 for (i=0; i<3; i++) {
800deef3 2870 list_for_each_entry_safe(lock, next, queue, list) {
6714d8e8
KH		 2871 if (lock->ml.node != dlm->node_num) {
2872 mlog(0, "putting lock for node %u\n",
2873 lock->ml.node);
2874 /* be extra careful */
2875 BUG_ON(!list_empty(&lock->ast_list));
2876 BUG_ON(!list_empty(&lock->bast_list));
2877 BUG_ON(lock->ast_pending);
2878 BUG_ON(lock->bast_pending);
8d400b81
SM		 2879 dlm_lockres_clear_refmap_bit(dlm, res,
2880 lock->ml.node);
6714d8e8
KH		 2881 list_del_init(&lock->list);
2882 dlm_lock_put(lock);
2c5c54ac
SM		 2883 /* In a normal unlock, we would have added a
2884 * DLM_UNLOCK_FREE_LOCK action. Force it. */
2885 dlm_lock_put(lock);
6714d8e8
KH		 2886 }
2887 }
2888 queue++;
2889 }
ba2bf218
KH		 2890 bit = 0;
2891 while (1) {
2892 bit = find_next_bit(res->refmap, O2NM_MAX_NODES, bit);
2893 if (bit >= O2NM_MAX_NODES)
2894 break;
2895 /* do not clear the local node reference, if there is a
2896 * process holding this, let it drop the ref itself */
2897 if (bit != dlm->node_num) {
2898 mlog(0, "%s:%.*s: node %u had a ref to this "
2899 "migrating lockres, clearing\n", dlm->name,
2900 res->lockname.len, res->lockname.name, bit);
8d400b81 2901 dlm_lockres_clear_refmap_bit(dlm, res, bit);
ba2bf218
KH		 2902 }
2903 bit++;
2904 }
6714d8e8
KH		 2905}
2906
66effd3c
SM		 2907/*
2908 * Pick a node to migrate the lock resource to. This function selects a
2909 * potential target based first on the locks and then on refmap. It skips
2910 * nodes that are in the process of exiting the domain.
2911 */
6714d8e8
KH		 2912static u8 dlm_pick_migration_target(struct dlm_ctxt *dlm,
2913 struct dlm_lock_resource *res)
2914{
66effd3c 2915 enum dlm_lockres_list idx;
6714d8e8 2916 struct list_head *queue = &res->granted;
6714d8e8 2917 struct dlm_lock *lock;
66effd3c
SM		 2918 int noderef;
2919 u8 nodenum = O2NM_MAX_NODES;
6714d8e8
KH		 2920
2921 assert_spin_locked(&dlm->spinlock);
66effd3c 2922 assert_spin_locked(&res->spinlock);
6714d8e8 2923
66effd3c
SM		 2924 /* Go through all the locks */
2925 for (idx = DLM_GRANTED_LIST; idx <= DLM_BLOCKED_LIST; idx++) {
2926 queue = dlm_list_idx_to_ptr(res, idx);
800deef3 2927 list_for_each_entry(lock, queue, list) {
66effd3c
SM		 2928 if (lock->ml.node == dlm->node_num)
2929 continue;
2930 if (test_bit(lock->ml.node, dlm->exit_domain_map))
2931 continue;
2932 nodenum = lock->ml.node;
2933 goto bail;
6714d8e8 2934 }
6714d8e8 2935 }
388c4bcb 2936
66effd3c
SM		 2937 /* Go thru the refmap */
2938 noderef = -1;
6714d8e8 2939 while (1) {
66effd3c
SM		 2940 noderef = find_next_bit(res->refmap, O2NM_MAX_NODES,
2941 noderef + 1);
2942 if (noderef >= O2NM_MAX_NODES)
6714d8e8 2943 break;
66effd3c
SM		 2944 if (noderef == dlm->node_num)
2945 continue;
2946 if (test_bit(noderef, dlm->exit_domain_map))
2947 continue;
2948 nodenum = noderef;
2949 goto bail;
6714d8e8
KH		 2950 }
2951
66effd3c
SM		 2952bail:
2953 return nodenum;
6714d8e8
KH		 2954}
2955
6714d8e8
KH		 2956/* this is called by the new master once all lockres
2957 * data has been received */
2958static int dlm_do_migrate_request(struct dlm_ctxt *dlm,
2959 struct dlm_lock_resource *res,
2960 u8 master, u8 new_master,
2961 struct dlm_node_iter *iter)
2962{
2963 struct dlm_migrate_request migrate;
2b832564 2964 int ret, skip, status = 0;
6714d8e8
KH		 2965 int nodenum;
2966
2967 memset(&migrate, 0, sizeof(migrate));
2968 migrate.namelen = res->lockname.len;
2969 memcpy(migrate.name, res->lockname.name, migrate.namelen);
2970 migrate.new_master = new_master;
2971 migrate.master = master;
2972
2973 ret = 0;
2974
2975 /* send message to all nodes, except the master and myself */
2976 while ((nodenum = dlm_node_iter_next(iter)) >= 0) {
2977 if (nodenum == master ||
2978 nodenum == new_master)
2979 continue;
2980
2b832564
SM		 2981 /* We could race exit domain. If exited, skip. */
2982 spin_lock(&dlm->spinlock);
2983 skip = (!test_bit(nodenum, dlm->domain_map));
2984 spin_unlock(&dlm->spinlock);
2985 if (skip) {
2986 clear_bit(nodenum, iter->node_map);
2987 continue;
2988 }
2989
6714d8e8
KH		 2990 ret = o2net_send_message(DLM_MIGRATE_REQUEST_MSG, dlm->key,
2991 &migrate, sizeof(migrate), nodenum,
2992 &status);
2b832564 2993 if (ret < 0) {
8decab3c
SM		 2994 mlog(ML_ERROR, "%s: res %.*s, Error %d send "
2995 "MIGRATE_REQUEST to node %u\n", dlm->name,
2996 migrate.namelen, migrate.name, ret, nodenum);
2b832564
SM		 2997 if (!dlm_is_host_down(ret)) {
2998 mlog(ML_ERROR, "unhandled error=%d!\n", ret);
2999 BUG();
3000 }
3001 clear_bit(nodenum, iter->node_map);
3002 ret = 0;
3003 } else if (status < 0) {
6714d8e8
KH		 3004 mlog(0, "migrate request (node %u) returned %d!\n",
3005 nodenum, status);
3006 ret = status;
ba2bf218
KH		 3007 } else if (status == DLM_MIGRATE_RESPONSE_MASTERY_REF) {
3008 /* during the migration request we short-circuited
3009 * the mastery of the lockres. make sure we have
3010 * a mastery ref for nodenum */
3011 mlog(0, "%s:%.*s: need ref for node %u\n",
3012 dlm->name, res->lockname.len, res->lockname.name,
3013 nodenum);
3014 spin_lock(&res->spinlock);
8d400b81 3015 dlm_lockres_set_refmap_bit(dlm, res, nodenum);
ba2bf218 3016 spin_unlock(&res->spinlock);
6714d8e8
KH		 3017 }
3018 }
3019
3020 if (ret < 0)
3021 mlog_errno(ret);
3022
3023 mlog(0, "returning ret=%d\n", ret);
3024 return ret;
3025}
3026
3027
3028/* if there is an existing mle for this lockres, we now know who the master is.
3029 * (the one who sent us *this* message) we can clear it up right away.
3030 * since the process that put the mle on the list still has a reference to it,
3031 * we can unhash it now, set the master and wake the process. as a result,
3032 * we will have no mle in the list to start with. now we can add an mle for
3033 * the migration and this should be the only one found for those scanning the
3034 * list. */
d74c9803
KH		 3035int dlm_migrate_request_handler(struct o2net_msg *msg, u32 len, void *data,
3036 void **ret_data)
6714d8e8
KH		 3037{
3038 struct dlm_ctxt *dlm = data;
3039 struct dlm_lock_resource *res = NULL;
3040 struct dlm_migrate_request *migrate = (struct dlm_migrate_request *) msg->buf;
3041 struct dlm_master_list_entry *mle = NULL, *oldmle = NULL;
3042 const char *name;
a3d33291 3043 unsigned int namelen, hash;
6714d8e8
KH		 3044 int ret = 0;
3045
3046 if (!dlm_grab(dlm))
3047 return -EINVAL;
3048
3049 name = migrate->name;
3050 namelen = migrate->namelen;
a3d33291 3051 hash = dlm_lockid_hash(name, namelen);
6714d8e8
KH		 3052
3053 /* preallocate.. if this fails, abort */
3914ed0c 3054 mle = kmem_cache_alloc(dlm_mle_cache, GFP_NOFS);
6714d8e8
KH		 3055
3056 if (!mle) {
3057 ret = -ENOMEM;
3058 goto leave;
3059 }
3060
3061 /* check for pre-existing lock */
3062 spin_lock(&dlm->spinlock);
a3d33291 3063 res = __dlm_lookup_lockres(dlm, name, namelen, hash);
6714d8e8
KH		 3064 if (res) {
3065 spin_lock(&res->spinlock);
3066 if (res->state & DLM_LOCK_RES_RECOVERING) {
3067 /* if all is working ok, this can only mean that we got
3068 * a migrate request from a node that we now see as
3069 * dead. what can we do here? drop it to the floor? */
3070 spin_unlock(&res->spinlock);
3071 mlog(ML_ERROR, "Got a migrate request, but the "
3072 "lockres is marked as recovering!");
3073 kmem_cache_free(dlm_mle_cache, mle);
3074 ret = -EINVAL; /* need a better solution */
3075 goto unlock;
3076 }
3077 res->state |= DLM_LOCK_RES_MIGRATING;
3078 spin_unlock(&res->spinlock);
3079 }
3080
6d98c3cc 3081 spin_lock(&dlm->master_lock);
6714d8e8
KH		 3082 /* ignore status. only nonzero status would BUG. */
3083 ret = dlm_add_migration_mle(dlm, res, mle, &oldmle,
3084 name, namelen,
3085 migrate->new_master,
3086 migrate->master);
3087
6714d8e8 3088 spin_unlock(&dlm->master_lock);
6d98c3cc 3089unlock:
6714d8e8
KH		 3090 spin_unlock(&dlm->spinlock);
3091
3092 if (oldmle) {
3093 /* master is known, detach if not already detached */
3094 dlm_mle_detach_hb_events(dlm, oldmle);
3095 dlm_put_mle(oldmle);
3096 }
3097
3098 if (res)
3099 dlm_lockres_put(res);
3100leave:
3101 dlm_put(dlm);
3102 return ret;
3103}
3104
3105/* must be holding dlm->spinlock and dlm->master_lock
3106 * when adding a migration mle, we can clear any other mles
3107 * in the master list because we know with certainty that
3108 * the master is "master". so we remove any old mle from
3109 * the list after setting it's master field, and then add
3110 * the new migration mle. this way we can hold with the rule
3111 * of having only one mle for a given lock name at all times. */
3112static int dlm_add_migration_mle(struct dlm_ctxt *dlm,
3113 struct dlm_lock_resource *res,
3114 struct dlm_master_list_entry *mle,
3115 struct dlm_master_list_entry **oldmle,
3116 const char *name, unsigned int namelen,
3117 u8 new_master, u8 master)
3118{
3119 int found;
3120 int ret = 0;
3121
3122 *oldmle = NULL;
3123
6714d8e8
KH		 3124 assert_spin_locked(&dlm->spinlock);
3125 assert_spin_locked(&dlm->master_lock);
3126
3127 /* caller is responsible for any ref taken here on oldmle */
3128 found = dlm_find_mle(dlm, oldmle, (char *)name, namelen);
3129 if (found) {
3130 struct dlm_master_list_entry *tmp = *oldmle;
3131 spin_lock(&tmp->spinlock);
3132 if (tmp->type == DLM_MLE_MIGRATION) {
3133 if (master == dlm->node_num) {
3134 /* ah another process raced me to it */
3135 mlog(0, "tried to migrate %.*s, but some "
3136 "process beat me to it\n",
3137 namelen, name);
3138 ret = -EEXIST;
3139 } else {
3140 /* bad. 2 NODES are trying to migrate! */
3141 mlog(ML_ERROR, "migration error mle: "
3142 "master=%u new_master=%u // request: "
3143 "master=%u new_master=%u // "
3144 "lockres=%.*s\n",
3145 tmp->master, tmp->new_master,
3146 master, new_master,
3147 namelen, name);
3148 BUG();
3149 }
3150 } else {
3151 /* this is essentially what assert_master does */
3152 tmp->master = master;
3153 atomic_set(&tmp->woken, 1);
3154 wake_up(&tmp->wq);
1c084577
SM		 3155 /* remove it so that only one mle will be found */
3156 __dlm_unlink_mle(dlm, tmp);
ba2bf218 3157 __dlm_mle_detach_hb_events(dlm, tmp);
b9aaac5a 3158 if (tmp->type == DLM_MLE_MASTER) {
3159 ret = DLM_MIGRATE_RESPONSE_MASTERY_REF;
3160 mlog(0, "%s:%.*s: master=%u, newmaster=%u, "
3161 "telling master to get ref "
3162 "for cleared out mle during "
3163 "migration\n", dlm->name,
3164 namelen, name, master,
3165 new_master);
3166 }
6714d8e8
KH		 3167 }
3168 spin_unlock(&tmp->spinlock);
3169 }
3170
3171 /* now add a migration mle to the tail of the list */
3172 dlm_init_mle(mle, DLM_MLE_MIGRATION, dlm, res, name, namelen);
3173 mle->new_master = new_master;
ba2bf218
KH		 3174 /* the new master will be sending an assert master for this.
3175 * at that point we will get the refmap reference */
6714d8e8
KH		 3176 mle->master = master;
3177 /* do this for consistency with other mle types */
3178 set_bit(new_master, mle->maybe_map);
1c084577 3179 __dlm_insert_mle(dlm, mle);
6714d8e8
KH		 3180
3181 return ret;
3182}
3183
c2cd4a44
SM		 3184/*
3185 * Sets the owner of the lockres, associated to the mle, to UNKNOWN
3186 */
3187static struct dlm_lock_resource *dlm_reset_mleres_owner(struct dlm_ctxt *dlm,
3188 struct dlm_master_list_entry *mle)
3189{
3190 struct dlm_lock_resource *res;
c2cd4a44
SM		 3191
3192 /* Find the lockres associated to the mle and set its owner to UNK */
7141514b
SM		 3193 res = __dlm_lookup_lockres(dlm, mle->mname, mle->mnamelen,
3194 mle->mnamehash);
c2cd4a44
SM		 3195 if (res) {
3196 spin_unlock(&dlm->master_lock);
3197
3198 /* move lockres onto recovery list */
3199 spin_lock(&res->spinlock);
3200 dlm_set_lockres_owner(dlm, res, DLM_LOCK_RES_OWNER_UNKNOWN);
3201 dlm_move_lockres_to_recovery_list(dlm, res);
3202 spin_unlock(&res->spinlock);
3203 dlm_lockres_put(res);
3204
3205 /* about to get rid of mle, detach from heartbeat */
3206 __dlm_mle_detach_hb_events(dlm, mle);
3207
3208 /* dump the mle */
3209 spin_lock(&dlm->master_lock);
3210 __dlm_put_mle(mle);
3211 spin_unlock(&dlm->master_lock);
3212 }
3213
3214 return res;
3215}
3216
3217static void dlm_clean_migration_mle(struct dlm_ctxt *dlm,
3218 struct dlm_master_list_entry *mle)
3219{
3220 __dlm_mle_detach_hb_events(dlm, mle);
3221
3222 spin_lock(&mle->spinlock);
3223 __dlm_unlink_mle(dlm, mle);
3224 atomic_set(&mle->woken, 1);
3225 spin_unlock(&mle->spinlock);
3226
3227 wake_up(&mle->wq);
3228}
3229
3230static void dlm_clean_block_mle(struct dlm_ctxt *dlm,
3231 struct dlm_master_list_entry *mle, u8 dead_node)
3232{
3233 int bit;
3234
3235 BUG_ON(mle->type != DLM_MLE_BLOCK);
3236
3237 spin_lock(&mle->spinlock);
3238 bit = find_next_bit(mle->maybe_map, O2NM_MAX_NODES, 0);
3239 if (bit != dead_node) {
3240 mlog(0, "mle found, but dead node %u would not have been "
3241 "master\n", dead_node);
3242 spin_unlock(&mle->spinlock);
3243 } else {
3244 /* Must drop the refcount by one since the assert_master will
3245 * never arrive. This may result in the mle being unlinked and
3246 * freed, but there may still be a process waiting in the
3247 * dlmlock path which is fine. */
3248 mlog(0, "node %u was expected master\n", dead_node);
3249 atomic_set(&mle->woken, 1);
3250 spin_unlock(&mle->spinlock);
3251 wake_up(&mle->wq);
3252
3253 /* Do not need events any longer, so detach from heartbeat */
3254 __dlm_mle_detach_hb_events(dlm, mle);
3255 __dlm_put_mle(mle);
3256 }
3257}
6714d8e8
KH		 3258
3259void dlm_clean_master_list(struct dlm_ctxt *dlm, u8 dead_node)
3260{
2ed6c750 3261 struct dlm_master_list_entry *mle;
6714d8e8 3262 struct dlm_lock_resource *res;
2ed6c750 3263 struct hlist_head *bucket;
df53cd3b 3264 struct hlist_node *tmp;
2ed6c750 3265 unsigned int i;
6714d8e8 3266
ef6b689b 3267 mlog(0, "dlm=%s, dead node=%u\n", dlm->name, dead_node);
6714d8e8
KH		 3268top:
3269 assert_spin_locked(&dlm->spinlock);
3270
3271 /* clean the master list */
3272 spin_lock(&dlm->master_lock);
2ed6c750
SM		 3273 for (i = 0; i < DLM_HASH_BUCKETS; i++) {
3274 bucket = dlm_master_hash(dlm, i);
df53cd3b 3275 hlist_for_each_entry_safe(mle, tmp, bucket, master_hash_node) {
67ae1f06
SM		 3276 BUG_ON(mle->type != DLM_MLE_BLOCK &&
3277 mle->type != DLM_MLE_MASTER &&
3278 mle->type != DLM_MLE_MIGRATION);
3279
3280 /* MASTER mles are initiated locally. The waiting
3281 * process will notice the node map change shortly.
3282 * Let that happen as normal. */
3283 if (mle->type == DLM_MLE_MASTER)
3284 continue;
3285
3286 /* BLOCK mles are initiated by other nodes. Need to
3287 * clean up if the dead node would have been the
3288 * master. */
3289 if (mle->type == DLM_MLE_BLOCK) {
3290 dlm_clean_block_mle(dlm, mle, dead_node);
3291 continue;
3292 }
6714d8e8 3293
67ae1f06
SM		 3294 /* Everything else is a MIGRATION mle */
3295
3296 /* The rule for MIGRATION mles is that the master
3297 * becomes UNKNOWN if *either* the original or the new
3298 * master dies. All UNKNOWN lockres' are sent to
3299 * whichever node becomes the recovery master. The new
3300 * master is responsible for determining if there is
3301 * still a master for this lockres, or if he needs to
3302 * take over mastery. Either way, this node should
3303 * expect another message to resolve this. */
3304
3305 if (mle->master != dead_node &&
3306 mle->new_master != dead_node)
3307 continue;
3308
3309 /* If we have reached this point, this mle needs to be
3310 * removed from the list and freed. */
3311 dlm_clean_migration_mle(dlm, mle);
3312
3313 mlog(0, "%s: node %u died during migration from "
3314 "%u to %u!\n", dlm->name, dead_node, mle->master,
3315 mle->new_master);
3316
3317 /* If we find a lockres associated with the mle, we've
3318 * hit this rare case that messes up our lock ordering.
3319 * If so, we need to drop the master lock so that we can
3320 * take the lockres lock, meaning that we will have to
3321 * restart from the head of list. */
3322 res = dlm_reset_mleres_owner(dlm, mle);
3323 if (res)
3324 /* restart */
3325 goto top;
3326
3327 /* This may be the last reference */
3328 __dlm_put_mle(mle);
6714d8e8 3329 }
2ed6c750 3330 }
6714d8e8
KH		 3331 spin_unlock(&dlm->master_lock);
3332}
3333
6714d8e8
KH		 3334int dlm_finish_migration(struct dlm_ctxt *dlm, struct dlm_lock_resource *res,
3335 u8 old_master)
3336{
3337 struct dlm_node_iter iter;
3338 int ret = 0;
3339
3340 spin_lock(&dlm->spinlock);
3341 dlm_node_iter_init(dlm->domain_map, &iter);
3342 clear_bit(old_master, iter.node_map);
3343 clear_bit(dlm->node_num, iter.node_map);
3344 spin_unlock(&dlm->spinlock);
3345
ba2bf218
KH		 3346 /* ownership of the lockres is changing. account for the
3347 * mastery reference here since old_master will briefly have
3348 * a reference after the migration completes */
3349 spin_lock(&res->spinlock);
8d400b81 3350 dlm_lockres_set_refmap_bit(dlm, res, old_master);
ba2bf218
KH		 3351 spin_unlock(&res->spinlock);
3352
6714d8e8
KH		 3353 mlog(0, "now time to do a migrate request to other nodes\n");
3354 ret = dlm_do_migrate_request(dlm, res, old_master,
3355 dlm->node_num, &iter);
3356 if (ret < 0) {
3357 mlog_errno(ret);
3358 goto leave;
3359 }
3360
3361 mlog(0, "doing assert master of %.*s to all except the original node\n",
3362 res->lockname.len, res->lockname.name);
3363 /* this call now finishes out the nodemap
3364 * even if one or more nodes die */
ba2bf218 3365 ret = dlm_do_assert_master(dlm, res, iter.node_map,
6714d8e8
KH		 3366 DLM_ASSERT_MASTER_FINISH_MIGRATION);
3367 if (ret < 0) {
3368 /* no longer need to retry. all living nodes contacted. */
3369 mlog_errno(ret);
3370 ret = 0;
3371 }
3372
3373 memset(iter.node_map, 0, sizeof(iter.node_map));
3374 set_bit(old_master, iter.node_map);
3375 mlog(0, "doing assert master of %.*s back to %u\n",
3376 res->lockname.len, res->lockname.name, old_master);
ba2bf218 3377 ret = dlm_do_assert_master(dlm, res, iter.node_map,
6714d8e8
KH		 3378 DLM_ASSERT_MASTER_FINISH_MIGRATION);
3379 if (ret < 0) {
3380 mlog(0, "assert master to original master failed "
3381 "with %d.\n", ret);
3382 /* the only nonzero status here would be because of
3383 * a dead original node. we're done. */
3384 ret = 0;
3385 }
3386
3387 /* all done, set the owner, clear the flag */
3388 spin_lock(&res->spinlock);
3389 dlm_set_lockres_owner(dlm, res, dlm->node_num);
3390 res->state &= ~DLM_LOCK_RES_MIGRATING;
3391 spin_unlock(&res->spinlock);
3392 /* re-dirty it on the new master */
3393 dlm_kick_thread(dlm, res);
3394 wake_up(&res->wq);
3395leave:
3396 return ret;
3397}
3398
3399/*
3400 * LOCKRES AST REFCOUNT
3401 * this is integral to migration
3402 */
3403
3404/* for future intent to call an ast, reserve one ahead of time.
3405 * this should be called only after waiting on the lockres
3406 * with dlm_wait_on_lockres, and while still holding the
3407 * spinlock after the call. */
3408void __dlm_lockres_reserve_ast(struct dlm_lock_resource *res)
3409{
3410 assert_spin_locked(&res->spinlock);
3411 if (res->state & DLM_LOCK_RES_MIGRATING) {
3412 __dlm_print_one_lock_resource(res);
3413 }
3414 BUG_ON(res->state & DLM_LOCK_RES_MIGRATING);
3415
3416 atomic_inc(&res->asts_reserved);
3417}
3418
3419/*
3420 * used to drop the reserved ast, either because it went unused,
3421 * or because the ast/bast was actually called.
3422 *
3423 * also, if there is a pending migration on this lockres,
3424 * and this was the last pending ast on the lockres,
3425 * atomically set the MIGRATING flag before we drop the lock.
3426 * this is how we ensure that migration can proceed with no
3427 * asts in progress. note that it is ok if the state of the
3428 * queues is such that a lock should be granted in the future
3429 * or that a bast should be fired, because the new master will
3430 * shuffle the lists on this lockres as soon as it is migrated.
3431 */
3432void dlm_lockres_release_ast(struct dlm_ctxt *dlm,
3433 struct dlm_lock_resource *res)
3434{
3435 if (!atomic_dec_and_lock(&res->asts_reserved, &res->spinlock))
3436 return;
3437
3438 if (!res->migration_pending) {
3439 spin_unlock(&res->spinlock);
3440 return;
3441 }
3442
3443 BUG_ON(res->state & DLM_LOCK_RES_MIGRATING);
3444 res->migration_pending = 0;
3445 res->state |= DLM_LOCK_RES_MIGRATING;
3446 spin_unlock(&res->spinlock);
3447 wake_up(&res->wq);
3448 wake_up(&dlm->migration_wq);
3449}
5dad6c39
SE		 3450
3451void dlm_force_free_mles(struct dlm_ctxt *dlm)
3452{
3453 int i;
3454 struct hlist_head *bucket;
3455 struct dlm_master_list_entry *mle;
df53cd3b 3456 struct hlist_node *tmp;
5dad6c39
SE		 3457
3458 /*
3459 * We notified all other nodes that we are exiting the domain and
3460 * marked the dlm state to DLM_CTXT_LEAVING. If any mles are still
3461 * around we force free them and wake any processes that are waiting
3462 * on the mles
3463 */
3464 spin_lock(&dlm->spinlock);
3465 spin_lock(&dlm->master_lock);
3466
3467 BUG_ON(dlm->dlm_state != DLM_CTXT_LEAVING);
3468 BUG_ON((find_next_bit(dlm->domain_map, O2NM_MAX_NODES, 0) < O2NM_MAX_NODES));
3469
3470 for (i = 0; i < DLM_HASH_BUCKETS; i++) {
3471 bucket = dlm_master_hash(dlm, i);
df53cd3b 3472 hlist_for_each_entry_safe(mle, tmp, bucket, master_hash_node) {
5dad6c39
SE		 3473 if (mle->type != DLM_MLE_BLOCK) {
3474 mlog(ML_ERROR, "bad mle: %p\n", mle);
3475 dlm_print_one_mle(mle);
3476 }
3477 atomic_set(&mle->woken, 1);
3478 wake_up(&mle->wq);
3479
3480 __dlm_unlink_mle(dlm, mle);
3481 __dlm_mle_detach_hb_events(dlm, mle);
3482 __dlm_put_mle(mle);
3483 }
3484 }
3485 spin_unlock(&dlm->master_lock);
3486 spin_unlock(&dlm->spinlock);
3487}
Linux 6.x block layer and io_uring tree(s)