1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* -*- mode: c; c-basic-offset: 8; -*-
3 * vim: noexpandtab sw=8 ts=8 sts=0:
4 *
5 * dlmlock.c
6 *
7 * underlying calls for lock creation
8 *
9 * Copyright (C) 2004 Oracle. All rights reserved.
10 */
11
12
13 #include <linux/module.h>
14 #include <linux/fs.h>
15 #include <linux/types.h>
16 #include <linux/slab.h>
17 #include <linux/highmem.h>
18 #include <linux/init.h>
19 #include <linux/sysctl.h>
20 #include <linux/random.h>
21 #include <linux/blkdev.h>
22 #include <linux/socket.h>
23 #include <linux/inet.h>
24 #include <linux/spinlock.h>
25 #include <linux/delay.h>
26
27
28 #include "../cluster/heartbeat.h"
29 #include "../cluster/nodemanager.h"
30 #include "../cluster/tcp.h"
31
32 #include "dlmapi.h"
33 #include "dlmcommon.h"
34
35 #include "dlmconvert.h"
36
37 #define MLOG_MASK_PREFIX ML_DLM
38 #include "../cluster/masklog.h"
39
40 static struct kmem_cache *dlm_lock_cache;
41
42 static DEFINE_SPINLOCK(dlm_cookie_lock);
43 static u64 dlm_next_cookie = 1;
44
45 static enum dlm_status dlm_send_remote_lock_request(struct dlm_ctxt *dlm,
46 struct dlm_lock_resource *res,
47 struct dlm_lock *lock, int flags);
48 static void dlm_init_lock(struct dlm_lock *newlock, int type,
49 u8 node, u64 cookie);
50 static void dlm_lock_release(struct kref *kref);
51 static void dlm_lock_detach_lockres(struct dlm_lock *lock);
52
dlm_init_lock_cache(void)53 int dlm_init_lock_cache(void)
54 {
55 dlm_lock_cache = kmem_cache_create("o2dlm_lock",
56 sizeof(struct dlm_lock),
57 0, SLAB_HWCACHE_ALIGN, NULL);
58 if (dlm_lock_cache == NULL)
59 return -ENOMEM;
60 return 0;
61 }
62
dlm_destroy_lock_cache(void)63 void dlm_destroy_lock_cache(void)
64 {
65 kmem_cache_destroy(dlm_lock_cache);
66 }
67
68 /* Tell us whether we can grant a new lock request.
69 * locking:
70 * caller needs: res->spinlock
71 * taken: none
72 * held on exit: none
73 * returns: 1 if the lock can be granted, 0 otherwise.
74 */
dlm_can_grant_new_lock(struct dlm_lock_resource * res,struct dlm_lock * lock)75 static int dlm_can_grant_new_lock(struct dlm_lock_resource *res,
76 struct dlm_lock *lock)
77 {
78 struct dlm_lock *tmplock;
79
80 list_for_each_entry(tmplock, &res->granted, list) {
81 if (!dlm_lock_compatible(tmplock->ml.type, lock->ml.type))
82 return 0;
83 }
84
85 list_for_each_entry(tmplock, &res->converting, list) {
86 if (!dlm_lock_compatible(tmplock->ml.type, lock->ml.type))
87 return 0;
88 if (!dlm_lock_compatible(tmplock->ml.convert_type,
89 lock->ml.type))
90 return 0;
91 }
92
93 return 1;
94 }
95
96 /* performs lock creation at the lockres master site
97 * locking:
98 * caller needs: none
99 * taken: takes and drops res->spinlock
100 * held on exit: none
101 * returns: DLM_NORMAL, DLM_NOTQUEUED
102 */
dlmlock_master(struct dlm_ctxt * dlm,struct dlm_lock_resource * res,struct dlm_lock * lock,int flags)103 static enum dlm_status dlmlock_master(struct dlm_ctxt *dlm,
104 struct dlm_lock_resource *res,
105 struct dlm_lock *lock, int flags)
106 {
107 int call_ast = 0, kick_thread = 0;
108 enum dlm_status status = DLM_NORMAL;
109
110 mlog(0, "type=%d\n", lock->ml.type);
111
112 spin_lock(&res->spinlock);
113 /* if called from dlm_create_lock_handler, need to
114 * ensure it will not sleep in dlm_wait_on_lockres */
115 status = __dlm_lockres_state_to_status(res);
116 if (status != DLM_NORMAL &&
117 lock->ml.node != dlm->node_num) {
118 /* erf. state changed after lock was dropped. */
119 spin_unlock(&res->spinlock);
120 dlm_error(status);
121 return status;
122 }
123 __dlm_wait_on_lockres(res);
124 __dlm_lockres_reserve_ast(res);
125
126 if (dlm_can_grant_new_lock(res, lock)) {
127 mlog(0, "I can grant this lock right away\n");
128 /* got it right away */
129 lock->lksb->status = DLM_NORMAL;
130 status = DLM_NORMAL;
131 dlm_lock_get(lock);
132 list_add_tail(&lock->list, &res->granted);
133
134 /* for the recovery lock, we can't allow the ast
135 * to be queued since the dlmthread is already
136 * frozen. but the recovery lock is always locked
137 * with LKM_NOQUEUE so we do not need the ast in
138 * this special case */
139 if (!dlm_is_recovery_lock(res->lockname.name,
140 res->lockname.len)) {
141 kick_thread = 1;
142 call_ast = 1;
143 } else {
144 mlog(0, "%s: returning DLM_NORMAL to "
145 "node %u for reco lock\n", dlm->name,
146 lock->ml.node);
147 }
148 } else {
149 /* for NOQUEUE request, unless we get the
150 * lock right away, return DLM_NOTQUEUED */
151 if (flags & LKM_NOQUEUE) {
152 status = DLM_NOTQUEUED;
153 if (dlm_is_recovery_lock(res->lockname.name,
154 res->lockname.len)) {
155 mlog(0, "%s: returning NOTQUEUED to "
156 "node %u for reco lock\n", dlm->name,
157 lock->ml.node);
158 }
159 } else {
160 status = DLM_NORMAL;
161 dlm_lock_get(lock);
162 list_add_tail(&lock->list, &res->blocked);
163 kick_thread = 1;
164 }
165 }
166
167 spin_unlock(&res->spinlock);
168 wake_up(&res->wq);
169
170 /* either queue the ast or release it */
171 if (call_ast)
172 dlm_queue_ast(dlm, lock);
173 else
174 dlm_lockres_release_ast(dlm, res);
175
176 dlm_lockres_calc_usage(dlm, res);
177 if (kick_thread)
178 dlm_kick_thread(dlm, res);
179
180 return status;
181 }
182
dlm_revert_pending_lock(struct dlm_lock_resource * res,struct dlm_lock * lock)183 void dlm_revert_pending_lock(struct dlm_lock_resource *res,
184 struct dlm_lock *lock)
185 {
186 /* remove from local queue if it failed */
187 list_del_init(&lock->list);
188 lock->lksb->flags &= ~DLM_LKSB_GET_LVB;
189 }
190
191
192 /*
193 * locking:
194 * caller needs: none
195 * taken: takes and drops res->spinlock
196 * held on exit: none
197 * returns: DLM_DENIED, DLM_RECOVERING, or net status
198 */
dlmlock_remote(struct dlm_ctxt * dlm,struct dlm_lock_resource * res,struct dlm_lock * lock,int flags)199 static enum dlm_status dlmlock_remote(struct dlm_ctxt *dlm,
200 struct dlm_lock_resource *res,
201 struct dlm_lock *lock, int flags)
202 {
203 enum dlm_status status = DLM_DENIED;
204 int lockres_changed = 1;
205
206 mlog(0, "type=%d, lockres %.*s, flags = 0x%x\n",
207 lock->ml.type, res->lockname.len,
208 res->lockname.name, flags);
209
210 /*
211 * Wait if resource is getting recovered, remastered, etc.
212 * If the resource was remastered and new owner is self, then exit.
213 */
214 spin_lock(&res->spinlock);
215 __dlm_wait_on_lockres(res);
216 if (res->owner == dlm->node_num) {
217 spin_unlock(&res->spinlock);
218 return DLM_RECOVERING;
219 }
220 res->state |= DLM_LOCK_RES_IN_PROGRESS;
221
222 /* add lock to local (secondary) queue */
223 dlm_lock_get(lock);
224 list_add_tail(&lock->list, &res->blocked);
225 lock->lock_pending = 1;
226 spin_unlock(&res->spinlock);
227
228 /* spec seems to say that you will get DLM_NORMAL when the lock
229 * has been queued, meaning we need to wait for a reply here. */
230 status = dlm_send_remote_lock_request(dlm, res, lock, flags);
231
232 spin_lock(&res->spinlock);
233 res->state &= ~DLM_LOCK_RES_IN_PROGRESS;
234 lock->lock_pending = 0;
235 if (status != DLM_NORMAL) {
236 if (status == DLM_RECOVERING &&
237 dlm_is_recovery_lock(res->lockname.name,
238 res->lockname.len)) {
239 /* recovery lock was mastered by dead node.
240 * we need to have calc_usage shoot down this
241 * lockres and completely remaster it. */
242 mlog(0, "%s: recovery lock was owned by "
243 "dead node %u, remaster it now.\n",
244 dlm->name, res->owner);
245 } else if (status != DLM_NOTQUEUED) {
246 /*
247 * DO NOT call calc_usage, as this would unhash
248 * the remote lockres before we ever get to use
249 * it. treat as if we never made any change to
250 * the lockres.
251 */
252 lockres_changed = 0;
253 dlm_error(status);
254 }
255 dlm_revert_pending_lock(res, lock);
256 dlm_lock_put(lock);
257 } else if (dlm_is_recovery_lock(res->lockname.name,
258 res->lockname.len)) {
259 /* special case for the $RECOVERY lock.
260 * there will never be an AST delivered to put
261 * this lock on the proper secondary queue
262 * (granted), so do it manually. */
263 mlog(0, "%s: $RECOVERY lock for this node (%u) is "
264 "mastered by %u; got lock, manually granting (no ast)\n",
265 dlm->name, dlm->node_num, res->owner);
266 list_move_tail(&lock->list, &res->granted);
267 }
268 spin_unlock(&res->spinlock);
269
270 if (lockres_changed)
271 dlm_lockres_calc_usage(dlm, res);
272
273 wake_up(&res->wq);
274 return status;
275 }
276
277
278 /* for remote lock creation.
279 * locking:
280 * caller needs: none, but need res->state & DLM_LOCK_RES_IN_PROGRESS
281 * taken: none
282 * held on exit: none
283 * returns: DLM_NOLOCKMGR, or net status
284 */
dlm_send_remote_lock_request(struct dlm_ctxt * dlm,struct dlm_lock_resource * res,struct dlm_lock * lock,int flags)285 static enum dlm_status dlm_send_remote_lock_request(struct dlm_ctxt *dlm,
286 struct dlm_lock_resource *res,
287 struct dlm_lock *lock, int flags)
288 {
289 struct dlm_create_lock create;
290 int tmpret, status = 0;
291 enum dlm_status ret;
292
293 memset(&create, 0, sizeof(create));
294 create.node_idx = dlm->node_num;
295 create.requested_type = lock->ml.type;
296 create.cookie = lock->ml.cookie;
297 create.namelen = res->lockname.len;
298 create.flags = cpu_to_be32(flags);
299 memcpy(create.name, res->lockname.name, create.namelen);
300
301 tmpret = o2net_send_message(DLM_CREATE_LOCK_MSG, dlm->key, &create,
302 sizeof(create), res->owner, &status);
303 if (tmpret >= 0) {
304 ret = status;
305 if (ret == DLM_REJECTED) {
306 mlog(ML_ERROR, "%s: res %.*s, Stale lockres no longer "
307 "owned by node %u. That node is coming back up "
308 "currently.\n", dlm->name, create.namelen,
309 create.name, res->owner);
310 dlm_print_one_lock_resource(res);
311 BUG();
312 }
313 } else {
314 mlog(ML_ERROR, "%s: res %.*s, Error %d send CREATE LOCK to "
315 "node %u\n", dlm->name, create.namelen, create.name,
316 tmpret, res->owner);
317 if (dlm_is_host_down(tmpret))
318 ret = DLM_RECOVERING;
319 else
320 ret = dlm_err_to_dlm_status(tmpret);
321 }
322
323 return ret;
324 }
325
dlm_lock_get(struct dlm_lock * lock)326 void dlm_lock_get(struct dlm_lock *lock)
327 {
328 kref_get(&lock->lock_refs);
329 }
330
dlm_lock_put(struct dlm_lock * lock)331 void dlm_lock_put(struct dlm_lock *lock)
332 {
333 kref_put(&lock->lock_refs, dlm_lock_release);
334 }
335
dlm_lock_release(struct kref * kref)336 static void dlm_lock_release(struct kref *kref)
337 {
338 struct dlm_lock *lock;
339
340 lock = container_of(kref, struct dlm_lock, lock_refs);
341
342 BUG_ON(!list_empty(&lock->list));
343 BUG_ON(!list_empty(&lock->ast_list));
344 BUG_ON(!list_empty(&lock->bast_list));
345 BUG_ON(lock->ast_pending);
346 BUG_ON(lock->bast_pending);
347
348 dlm_lock_detach_lockres(lock);
349
350 if (lock->lksb_kernel_allocated) {
351 mlog(0, "freeing kernel-allocated lksb\n");
352 kfree(lock->lksb);
353 }
354 kmem_cache_free(dlm_lock_cache, lock);
355 }
356
357 /* associate a lock with it's lockres, getting a ref on the lockres */
dlm_lock_attach_lockres(struct dlm_lock * lock,struct dlm_lock_resource * res)358 void dlm_lock_attach_lockres(struct dlm_lock *lock,
359 struct dlm_lock_resource *res)
360 {
361 dlm_lockres_get(res);
362 lock->lockres = res;
363 }
364
365 /* drop ref on lockres, if there is still one associated with lock */
dlm_lock_detach_lockres(struct dlm_lock * lock)366 static void dlm_lock_detach_lockres(struct dlm_lock *lock)
367 {
368 struct dlm_lock_resource *res;
369
370 res = lock->lockres;
371 if (res) {
372 lock->lockres = NULL;
373 mlog(0, "removing lock's lockres reference\n");
374 dlm_lockres_put(res);
375 }
376 }
377
dlm_init_lock(struct dlm_lock * newlock,int type,u8 node,u64 cookie)378 static void dlm_init_lock(struct dlm_lock *newlock, int type,
379 u8 node, u64 cookie)
380 {
381 INIT_LIST_HEAD(&newlock->list);
382 INIT_LIST_HEAD(&newlock->ast_list);
383 INIT_LIST_HEAD(&newlock->bast_list);
384 spin_lock_init(&newlock->spinlock);
385 newlock->ml.type = type;
386 newlock->ml.convert_type = LKM_IVMODE;
387 newlock->ml.highest_blocked = LKM_IVMODE;
388 newlock->ml.node = node;
389 newlock->ml.pad1 = 0;
390 newlock->ml.list = 0;
391 newlock->ml.flags = 0;
392 newlock->ast = NULL;
393 newlock->bast = NULL;
394 newlock->astdata = NULL;
395 newlock->ml.cookie = cpu_to_be64(cookie);
396 newlock->ast_pending = 0;
397 newlock->bast_pending = 0;
398 newlock->convert_pending = 0;
399 newlock->lock_pending = 0;
400 newlock->unlock_pending = 0;
401 newlock->cancel_pending = 0;
402 newlock->lksb_kernel_allocated = 0;
403
404 kref_init(&newlock->lock_refs);
405 }
406
dlm_new_lock(int type,u8 node,u64 cookie,struct dlm_lockstatus * lksb)407 struct dlm_lock * dlm_new_lock(int type, u8 node, u64 cookie,
408 struct dlm_lockstatus *lksb)
409 {
410 struct dlm_lock *lock;
411 int kernel_allocated = 0;
412
413 lock = kmem_cache_zalloc(dlm_lock_cache, GFP_NOFS);
414 if (!lock)
415 return NULL;
416
417 if (!lksb) {
418 /* zero memory only if kernel-allocated */
419 lksb = kzalloc(sizeof(*lksb), GFP_NOFS);
420 if (!lksb) {
421 kmem_cache_free(dlm_lock_cache, lock);
422 return NULL;
423 }
424 kernel_allocated = 1;
425 }
426
427 dlm_init_lock(lock, type, node, cookie);
428 if (kernel_allocated)
429 lock->lksb_kernel_allocated = 1;
430 lock->lksb = lksb;
431 lksb->lockid = lock;
432 return lock;
433 }
434
435 /* handler for lock creation net message
436 * locking:
437 * caller needs: none
438 * taken: takes and drops res->spinlock
439 * held on exit: none
440 * returns: DLM_NORMAL, DLM_SYSERR, DLM_IVLOCKID, DLM_NOTQUEUED
441 */
dlm_create_lock_handler(struct o2net_msg * msg,u32 len,void * data,void ** ret_data)442 int dlm_create_lock_handler(struct o2net_msg *msg, u32 len, void *data,
443 void **ret_data)
444 {
445 struct dlm_ctxt *dlm = data;
446 struct dlm_create_lock *create = (struct dlm_create_lock *)msg->buf;
447 struct dlm_lock_resource *res = NULL;
448 struct dlm_lock *newlock = NULL;
449 struct dlm_lockstatus *lksb = NULL;
450 enum dlm_status status = DLM_NORMAL;
451 char *name;
452 unsigned int namelen;
453
454 BUG_ON(!dlm);
455
456 if (!dlm_grab(dlm))
457 return DLM_REJECTED;
458
459 name = create->name;
460 namelen = create->namelen;
461 status = DLM_REJECTED;
462 if (!dlm_domain_fully_joined(dlm)) {
463 mlog(ML_ERROR, "Domain %s not fully joined, but node %u is "
464 "sending a create_lock message for lock %.*s!\n",
465 dlm->name, create->node_idx, namelen, name);
466 dlm_error(status);
467 goto leave;
468 }
469
470 status = DLM_IVBUFLEN;
471 if (namelen > DLM_LOCKID_NAME_MAX) {
472 dlm_error(status);
473 goto leave;
474 }
475
476 status = DLM_SYSERR;
477 newlock = dlm_new_lock(create->requested_type,
478 create->node_idx,
479 be64_to_cpu(create->cookie), NULL);
480 if (!newlock) {
481 dlm_error(status);
482 goto leave;
483 }
484
485 lksb = newlock->lksb;
486
487 if (be32_to_cpu(create->flags) & LKM_GET_LVB) {
488 lksb->flags |= DLM_LKSB_GET_LVB;
489 mlog(0, "set DLM_LKSB_GET_LVB flag\n");
490 }
491
492 status = DLM_IVLOCKID;
493 res = dlm_lookup_lockres(dlm, name, namelen);
494 if (!res) {
495 dlm_error(status);
496 goto leave;
497 }
498
499 spin_lock(&res->spinlock);
500 status = __dlm_lockres_state_to_status(res);
501 spin_unlock(&res->spinlock);
502
503 if (status != DLM_NORMAL) {
504 mlog(0, "lockres recovering/migrating/in-progress\n");
505 goto leave;
506 }
507
508 dlm_lock_attach_lockres(newlock, res);
509
510 status = dlmlock_master(dlm, res, newlock, be32_to_cpu(create->flags));
511 leave:
512 if (status != DLM_NORMAL)
513 if (newlock)
514 dlm_lock_put(newlock);
515
516 if (res)
517 dlm_lockres_put(res);
518
519 dlm_put(dlm);
520
521 return status;
522 }
523
524
525 /* fetch next node-local (u8 nodenum + u56 cookie) into u64 */
dlm_get_next_cookie(u8 node_num,u64 * cookie)526 static inline void dlm_get_next_cookie(u8 node_num, u64 *cookie)
527 {
528 u64 tmpnode = node_num;
529
530 /* shift single byte of node num into top 8 bits */
531 tmpnode <<= 56;
532
533 spin_lock(&dlm_cookie_lock);
534 *cookie = (dlm_next_cookie | tmpnode);
535 if (++dlm_next_cookie & 0xff00000000000000ull) {
536 mlog(0, "This node's cookie will now wrap!\n");
537 dlm_next_cookie = 1;
538 }
539 spin_unlock(&dlm_cookie_lock);
540 }
541
dlmlock(struct dlm_ctxt * dlm,int mode,struct dlm_lockstatus * lksb,int flags,const char * name,int namelen,dlm_astlockfunc_t * ast,void * data,dlm_bastlockfunc_t * bast)542 enum dlm_status dlmlock(struct dlm_ctxt *dlm, int mode,
543 struct dlm_lockstatus *lksb, int flags,
544 const char *name, int namelen, dlm_astlockfunc_t *ast,
545 void *data, dlm_bastlockfunc_t *bast)
546 {
547 enum dlm_status status;
548 struct dlm_lock_resource *res = NULL;
549 struct dlm_lock *lock = NULL;
550 int convert = 0, recovery = 0;
551
552 /* yes this function is a mess.
553 * TODO: clean this up. lots of common code in the
554 * lock and convert paths, especially in the retry blocks */
555 if (!lksb) {
556 dlm_error(DLM_BADARGS);
557 return DLM_BADARGS;
558 }
559
560 status = DLM_BADPARAM;
561 if (mode != LKM_EXMODE && mode != LKM_PRMODE && mode != LKM_NLMODE) {
562 dlm_error(status);
563 goto error;
564 }
565
566 if (flags & ~LKM_VALID_FLAGS) {
567 dlm_error(status);
568 goto error;
569 }
570
571 convert = (flags & LKM_CONVERT);
572 recovery = (flags & LKM_RECOVERY);
573
574 if (recovery &&
575 (!dlm_is_recovery_lock(name, namelen) || convert) ) {
576 dlm_error(status);
577 goto error;
578 }
579 if (convert && (flags & LKM_LOCAL)) {
580 mlog(ML_ERROR, "strange LOCAL convert request!\n");
581 goto error;
582 }
583
584 if (convert) {
585 /* CONVERT request */
586
587 /* if converting, must pass in a valid dlm_lock */
588 lock = lksb->lockid;
589 if (!lock) {
590 mlog(ML_ERROR, "NULL lock pointer in convert "
591 "request\n");
592 goto error;
593 }
594
595 res = lock->lockres;
596 if (!res) {
597 mlog(ML_ERROR, "NULL lockres pointer in convert "
598 "request\n");
599 goto error;
600 }
601 dlm_lockres_get(res);
602
603 /* XXX: for ocfs2 purposes, the ast/bast/astdata/lksb are
604 * static after the original lock call. convert requests will
605 * ensure that everything is the same, or return DLM_BADARGS.
606 * this means that DLM_DENIED_NOASTS will never be returned.
607 */
608 if (lock->lksb != lksb || lock->ast != ast ||
609 lock->bast != bast || lock->astdata != data) {
610 status = DLM_BADARGS;
611 mlog(ML_ERROR, "new args: lksb=%p, ast=%p, bast=%p, "
612 "astdata=%p\n", lksb, ast, bast, data);
613 mlog(ML_ERROR, "orig args: lksb=%p, ast=%p, bast=%p, "
614 "astdata=%p\n", lock->lksb, lock->ast,
615 lock->bast, lock->astdata);
616 goto error;
617 }
618 retry_convert:
619 dlm_wait_for_recovery(dlm);
620
621 if (res->owner == dlm->node_num)
622 status = dlmconvert_master(dlm, res, lock, flags, mode);
623 else
624 status = dlmconvert_remote(dlm, res, lock, flags, mode);
625 if (status == DLM_RECOVERING || status == DLM_MIGRATING ||
626 status == DLM_FORWARD) {
627 /* for now, see how this works without sleeping
628 * and just retry right away. I suspect the reco
629 * or migration will complete fast enough that
630 * no waiting will be necessary */
631 mlog(0, "retrying convert with migration/recovery/"
632 "in-progress\n");
633 msleep(100);
634 goto retry_convert;
635 }
636 } else {
637 u64 tmpcookie;
638
639 /* LOCK request */
640 status = DLM_BADARGS;
641 if (!name) {
642 dlm_error(status);
643 goto error;
644 }
645
646 status = DLM_IVBUFLEN;
647 if (namelen > DLM_LOCKID_NAME_MAX || namelen < 1) {
648 dlm_error(status);
649 goto error;
650 }
651
652 dlm_get_next_cookie(dlm->node_num, &tmpcookie);
653 lock = dlm_new_lock(mode, dlm->node_num, tmpcookie, lksb);
654 if (!lock) {
655 dlm_error(status);
656 goto error;
657 }
658
659 if (!recovery)
660 dlm_wait_for_recovery(dlm);
661
662 /* find or create the lock resource */
663 res = dlm_get_lock_resource(dlm, name, namelen, flags);
664 if (!res) {
665 status = DLM_IVLOCKID;
666 dlm_error(status);
667 goto error;
668 }
669
670 mlog(0, "type=%d, flags = 0x%x\n", mode, flags);
671 mlog(0, "creating lock: lock=%p res=%p\n", lock, res);
672
673 dlm_lock_attach_lockres(lock, res);
674 lock->ast = ast;
675 lock->bast = bast;
676 lock->astdata = data;
677
678 retry_lock:
679 if (flags & LKM_VALBLK) {
680 mlog(0, "LKM_VALBLK passed by caller\n");
681
682 /* LVB requests for non PR, PW or EX locks are
683 * ignored. */
684 if (mode < LKM_PRMODE)
685 flags &= ~LKM_VALBLK;
686 else {
687 flags |= LKM_GET_LVB;
688 lock->lksb->flags |= DLM_LKSB_GET_LVB;
689 }
690 }
691
692 if (res->owner == dlm->node_num)
693 status = dlmlock_master(dlm, res, lock, flags);
694 else
695 status = dlmlock_remote(dlm, res, lock, flags);
696
697 if (status == DLM_RECOVERING || status == DLM_MIGRATING ||
698 status == DLM_FORWARD) {
699 msleep(100);
700 if (recovery) {
701 if (status != DLM_RECOVERING)
702 goto retry_lock;
703 /* wait to see the node go down, then
704 * drop down and allow the lockres to
705 * get cleaned up. need to remaster. */
706 dlm_wait_for_node_death(dlm, res->owner,
707 DLM_NODE_DEATH_WAIT_MAX);
708 } else {
709 dlm_wait_for_recovery(dlm);
710 goto retry_lock;
711 }
712 }
713
714 /* Inflight taken in dlm_get_lock_resource() is dropped here */
715 spin_lock(&res->spinlock);
716 dlm_lockres_drop_inflight_ref(dlm, res);
717 spin_unlock(&res->spinlock);
718
719 dlm_lockres_calc_usage(dlm, res);
720 dlm_kick_thread(dlm, res);
721
722 if (status != DLM_NORMAL) {
723 lock->lksb->flags &= ~DLM_LKSB_GET_LVB;
724 if (status != DLM_NOTQUEUED)
725 dlm_error(status);
726 goto error;
727 }
728 }
729
730 error:
731 if (status != DLM_NORMAL) {
732 if (lock && !convert)
733 dlm_lock_put(lock);
734 // this is kind of unnecessary
735 lksb->status = status;
736 }
737
738 /* put lockres ref from the convert path
739 * or from dlm_get_lock_resource */
740 if (res)
741 dlm_lockres_put(res);
742
743 return status;
744 }
745 EXPORT_SYMBOL_GPL(dlmlock);
746
