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[fs/lustre-release.git] / lustre / ldlm / ldlm_lock.c
1 /*
2  * GPL HEADER START
3  *
4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 only,
8  * as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful, but
11  * WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * General Public License version 2 for more details (a copy is included
14  * in the LICENSE file that accompanied this code).
15  *
16  * You should have received a copy of the GNU General Public License
17  * version 2 along with this program; If not, see
18  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
19  *
20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
21  * CA 95054 USA or visit www.sun.com if you need additional information or
22  * have any questions.
23  *
24  * GPL HEADER END
25  */
26 /*
27  * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
28  * Use is subject to license terms.
29  *
30  * Copyright (c) 2010, 2013, Intel Corporation.
31  */
32 /*
33  * This file is part of Lustre, http://www.lustre.org/
34  * Lustre is a trademark of Sun Microsystems, Inc.
35  *
36  * lustre/ldlm/ldlm_lock.c
37  *
38  * Author: Peter Braam <braam@clusterfs.com>
39  * Author: Phil Schwan <phil@clusterfs.com>
40  */
41
42 #define DEBUG_SUBSYSTEM S_LDLM
43
44 #ifdef __KERNEL__
45 # include <libcfs/libcfs.h>
46 # include <linux/lustre_intent.h>
47 #else
48 # include <liblustre.h>
49 #endif
50
51 #include <obd_class.h>
52 #include "ldlm_internal.h"
53
54 /* lock types */
55 char *ldlm_lockname[] = {
56         [0] "--",
57         [LCK_EX] "EX",
58         [LCK_PW] "PW",
59         [LCK_PR] "PR",
60         [LCK_CW] "CW",
61         [LCK_CR] "CR",
62         [LCK_NL] "NL",
63         [LCK_GROUP] "GROUP",
64         [LCK_COS] "COS"
65 };
66 EXPORT_SYMBOL(ldlm_lockname);
67
68 char *ldlm_typename[] = {
69         [LDLM_PLAIN] "PLN",
70         [LDLM_EXTENT] "EXT",
71         [LDLM_FLOCK] "FLK",
72         [LDLM_IBITS] "IBT",
73 };
74 EXPORT_SYMBOL(ldlm_typename);
75
76 static ldlm_policy_wire_to_local_t ldlm_policy_wire18_to_local[] = {
77         [LDLM_PLAIN - LDLM_MIN_TYPE] ldlm_plain_policy_wire_to_local,
78         [LDLM_EXTENT - LDLM_MIN_TYPE] ldlm_extent_policy_wire_to_local,
79         [LDLM_FLOCK - LDLM_MIN_TYPE] ldlm_flock_policy_wire18_to_local,
80         [LDLM_IBITS - LDLM_MIN_TYPE] ldlm_ibits_policy_wire_to_local,
81 };
82
83 static ldlm_policy_wire_to_local_t ldlm_policy_wire21_to_local[] = {
84         [LDLM_PLAIN - LDLM_MIN_TYPE] ldlm_plain_policy_wire_to_local,
85         [LDLM_EXTENT - LDLM_MIN_TYPE] ldlm_extent_policy_wire_to_local,
86         [LDLM_FLOCK - LDLM_MIN_TYPE] ldlm_flock_policy_wire21_to_local,
87         [LDLM_IBITS - LDLM_MIN_TYPE] ldlm_ibits_policy_wire_to_local,
88 };
89
90 static ldlm_policy_local_to_wire_t ldlm_policy_local_to_wire[] = {
91         [LDLM_PLAIN - LDLM_MIN_TYPE] ldlm_plain_policy_local_to_wire,
92         [LDLM_EXTENT - LDLM_MIN_TYPE] ldlm_extent_policy_local_to_wire,
93         [LDLM_FLOCK - LDLM_MIN_TYPE] ldlm_flock_policy_local_to_wire,
94         [LDLM_IBITS - LDLM_MIN_TYPE] ldlm_ibits_policy_local_to_wire,
95 };
96
97 /**
98  * Converts lock policy from local format to on the wire lock_desc format
99  */
100 void ldlm_convert_policy_to_wire(ldlm_type_t type,
101                                  const ldlm_policy_data_t *lpolicy,
102                                  ldlm_wire_policy_data_t *wpolicy)
103 {
104         ldlm_policy_local_to_wire_t convert;
105
106         convert = ldlm_policy_local_to_wire[type - LDLM_MIN_TYPE];
107
108         convert(lpolicy, wpolicy);
109 }
110
111 /**
112  * Converts lock policy from on the wire lock_desc format to local format
113  */
114 void ldlm_convert_policy_to_local(struct obd_export *exp, ldlm_type_t type,
115                                   const ldlm_wire_policy_data_t *wpolicy,
116                                   ldlm_policy_data_t *lpolicy)
117 {
118         ldlm_policy_wire_to_local_t convert;
119         int new_client;
120
121         /** some badness for 2.0.0 clients, but 2.0.0 isn't supported */
122         new_client = (exp_connect_flags(exp) & OBD_CONNECT_FULL20) != 0;
123         if (new_client)
124                 convert = ldlm_policy_wire21_to_local[type - LDLM_MIN_TYPE];
125         else
126                 convert = ldlm_policy_wire18_to_local[type - LDLM_MIN_TYPE];
127
128         convert(wpolicy, lpolicy);
129 }
130
131 char *ldlm_it2str(int it)
132 {
133         switch (it) {
134         case IT_OPEN:
135                 return "open";
136         case IT_CREAT:
137                 return "creat";
138         case (IT_OPEN | IT_CREAT):
139                 return "open|creat";
140         case IT_READDIR:
141                 return "readdir";
142         case IT_GETATTR:
143                 return "getattr";
144         case IT_LOOKUP:
145                 return "lookup";
146         case IT_UNLINK:
147                 return "unlink";
148         case IT_GETXATTR:
149                 return "getxattr";
150         case IT_LAYOUT:
151                 return "layout";
152         default:
153                 CERROR("Unknown intent %d\n", it);
154                 return "UNKNOWN";
155         }
156 }
157 EXPORT_SYMBOL(ldlm_it2str);
158
159 extern cfs_mem_cache_t *ldlm_lock_slab;
160
161 #ifdef HAVE_SERVER_SUPPORT
162 static ldlm_processing_policy ldlm_processing_policy_table[] = {
163         [LDLM_PLAIN] ldlm_process_plain_lock,
164         [LDLM_EXTENT] ldlm_process_extent_lock,
165 # ifdef __KERNEL__
166         [LDLM_FLOCK] ldlm_process_flock_lock,
167 # endif
168         [LDLM_IBITS] ldlm_process_inodebits_lock,
169 };
170
171 ldlm_processing_policy ldlm_get_processing_policy(struct ldlm_resource *res)
172 {
173         return ldlm_processing_policy_table[res->lr_type];
174 }
175 EXPORT_SYMBOL(ldlm_get_processing_policy);
176 #endif /* HAVE_SERVER_SUPPORT */
177
178 void ldlm_register_intent(struct ldlm_namespace *ns, ldlm_res_policy arg)
179 {
180         ns->ns_policy = arg;
181 }
182 EXPORT_SYMBOL(ldlm_register_intent);
183
184 /*
185  * REFCOUNTED LOCK OBJECTS
186  */
187
188
189 /**
190  * Get a reference on a lock.
191  *
192  * Lock refcounts, during creation:
193  *   - one special one for allocation, dec'd only once in destroy
194  *   - one for being a lock that's in-use
195  *   - one for the addref associated with a new lock
196  */
197 struct ldlm_lock *ldlm_lock_get(struct ldlm_lock *lock)
198 {
199         cfs_atomic_inc(&lock->l_refc);
200         return lock;
201 }
202 EXPORT_SYMBOL(ldlm_lock_get);
203
204 /**
205  * Release lock reference.
206  *
207  * Also frees the lock if it was last reference.
208  */
209 void ldlm_lock_put(struct ldlm_lock *lock)
210 {
211         ENTRY;
212
213         LASSERT(lock->l_resource != LP_POISON);
214         LASSERT(cfs_atomic_read(&lock->l_refc) > 0);
215         if (cfs_atomic_dec_and_test(&lock->l_refc)) {
216                 struct ldlm_resource *res;
217
218                 LDLM_DEBUG(lock,
219                            "final lock_put on destroyed lock, freeing it.");
220
221                 res = lock->l_resource;
222                 LASSERT(lock->l_destroyed);
223                 LASSERT(cfs_list_empty(&lock->l_res_link));
224                 LASSERT(cfs_list_empty(&lock->l_pending_chain));
225
226                 lprocfs_counter_decr(ldlm_res_to_ns(res)->ns_stats,
227                                      LDLM_NSS_LOCKS);
228                 lu_ref_del(&res->lr_reference, "lock", lock);
229                 ldlm_resource_putref(res);
230                 lock->l_resource = NULL;
231                 if (lock->l_export) {
232                         class_export_lock_put(lock->l_export, lock);
233                         lock->l_export = NULL;
234                 }
235
236                 if (lock->l_lvb_data != NULL)
237                         OBD_FREE(lock->l_lvb_data, lock->l_lvb_len);
238
239                 ldlm_interval_free(ldlm_interval_detach(lock));
240                 lu_ref_fini(&lock->l_reference);
241                 OBD_FREE_RCU(lock, sizeof(*lock), &lock->l_handle);
242         }
243
244         EXIT;
245 }
246 EXPORT_SYMBOL(ldlm_lock_put);
247
248 /**
249  * Removes LDLM lock \a lock from LRU. Assumes LRU is already locked.
250  */
251 int ldlm_lock_remove_from_lru_nolock(struct ldlm_lock *lock)
252 {
253         int rc = 0;
254         if (!cfs_list_empty(&lock->l_lru)) {
255                 struct ldlm_namespace *ns = ldlm_lock_to_ns(lock);
256
257                 LASSERT(lock->l_resource->lr_type != LDLM_FLOCK);
258                 cfs_list_del_init(&lock->l_lru);
259                 if (lock->l_flags & LDLM_FL_SKIPPED)
260                         lock->l_flags &= ~LDLM_FL_SKIPPED;
261                 LASSERT(ns->ns_nr_unused > 0);
262                 ns->ns_nr_unused--;
263                 rc = 1;
264         }
265         return rc;
266 }
267
268 /**
269  * Removes LDLM lock \a lock from LRU. Obtains the LRU lock first.
270  */
271 int ldlm_lock_remove_from_lru(struct ldlm_lock *lock)
272 {
273         struct ldlm_namespace *ns = ldlm_lock_to_ns(lock);
274         int rc;
275
276         ENTRY;
277         if (lock->l_ns_srv) {
278                 LASSERT(cfs_list_empty(&lock->l_lru));
279                 RETURN(0);
280         }
281
282         spin_lock(&ns->ns_lock);
283         rc = ldlm_lock_remove_from_lru_nolock(lock);
284         spin_unlock(&ns->ns_lock);
285         EXIT;
286         return rc;
287 }
288
289 /**
290  * Adds LDLM lock \a lock to namespace LRU. Assumes LRU is already locked.
291  */
292 void ldlm_lock_add_to_lru_nolock(struct ldlm_lock *lock)
293 {
294         struct ldlm_namespace *ns = ldlm_lock_to_ns(lock);
295
296         lock->l_last_used = cfs_time_current();
297         LASSERT(cfs_list_empty(&lock->l_lru));
298         LASSERT(lock->l_resource->lr_type != LDLM_FLOCK);
299         cfs_list_add_tail(&lock->l_lru, &ns->ns_unused_list);
300         LASSERT(ns->ns_nr_unused >= 0);
301         ns->ns_nr_unused++;
302 }
303
304 /**
305  * Adds LDLM lock \a lock to namespace LRU. Obtains necessary LRU locks
306  * first.
307  */
308 void ldlm_lock_add_to_lru(struct ldlm_lock *lock)
309 {
310         struct ldlm_namespace *ns = ldlm_lock_to_ns(lock);
311
312         ENTRY;
313         spin_lock(&ns->ns_lock);
314         ldlm_lock_add_to_lru_nolock(lock);
315         spin_unlock(&ns->ns_lock);
316         EXIT;
317 }
318
319 /**
320  * Moves LDLM lock \a lock that is already in namespace LRU to the tail of
321  * the LRU. Performs necessary LRU locking
322  */
323 void ldlm_lock_touch_in_lru(struct ldlm_lock *lock)
324 {
325         struct ldlm_namespace *ns = ldlm_lock_to_ns(lock);
326
327         ENTRY;
328         if (lock->l_ns_srv) {
329                 LASSERT(cfs_list_empty(&lock->l_lru));
330                 EXIT;
331                 return;
332         }
333
334         spin_lock(&ns->ns_lock);
335         if (!cfs_list_empty(&lock->l_lru)) {
336                 ldlm_lock_remove_from_lru_nolock(lock);
337                 ldlm_lock_add_to_lru_nolock(lock);
338         }
339         spin_unlock(&ns->ns_lock);
340         EXIT;
341 }
342
343 /**
344  * Helper to destroy a locked lock.
345  *
346  * Used by ldlm_lock_destroy and ldlm_lock_destroy_nolock
347  * Must be called with l_lock and lr_lock held.
348  *
349  * Does not actually free the lock data, but rather marks the lock as
350  * destroyed by setting l_destroyed field in the lock to 1.  Destroys a
351  * handle->lock association too, so that the lock can no longer be found
352  * and removes the lock from LRU list.  Actual lock freeing occurs when
353  * last lock reference goes away.
354  *
355  * Original comment (of some historical value):
356  * This used to have a 'strict' flag, which recovery would use to mark an
357  * in-use lock as needing-to-die.  Lest I am ever tempted to put it back, I
358  * shall explain why it's gone: with the new hash table scheme, once you call
359  * ldlm_lock_destroy, you can never drop your final references on this lock.
360  * Because it's not in the hash table anymore.  -phil
361  */
362 int ldlm_lock_destroy_internal(struct ldlm_lock *lock)
363 {
364         ENTRY;
365
366         if (lock->l_readers || lock->l_writers) {
367                 LDLM_ERROR(lock, "lock still has references");
368                 LBUG();
369         }
370
371         if (!cfs_list_empty(&lock->l_res_link)) {
372                 LDLM_ERROR(lock, "lock still on resource");
373                 LBUG();
374         }
375
376         if (lock->l_destroyed) {
377                 LASSERT(cfs_list_empty(&lock->l_lru));
378                 EXIT;
379                 return 0;
380         }
381         lock->l_destroyed = 1;
382
383         if (lock->l_export && lock->l_export->exp_lock_hash) {
384                 /* NB: it's safe to call cfs_hash_del() even lock isn't
385                  * in exp_lock_hash. */
386                 /* In the function below, .hs_keycmp resolves to
387                  * ldlm_export_lock_keycmp() */
388                 /* coverity[overrun-buffer-val] */
389                 cfs_hash_del(lock->l_export->exp_lock_hash,
390                              &lock->l_remote_handle, &lock->l_exp_hash);
391         }
392
393         ldlm_lock_remove_from_lru(lock);
394         class_handle_unhash(&lock->l_handle);
395
396 #if 0
397         /* Wake anyone waiting for this lock */
398         /* FIXME: I should probably add yet another flag, instead of using
399          * l_export to only call this on clients */
400         if (lock->l_export)
401                 class_export_put(lock->l_export);
402         lock->l_export = NULL;
403         if (lock->l_export && lock->l_completion_ast)
404                 lock->l_completion_ast(lock, 0);
405 #endif
406         EXIT;
407         return 1;
408 }
409
410 /**
411  * Destroys a LDLM lock \a lock. Performs necessary locking first.
412  */
413 void ldlm_lock_destroy(struct ldlm_lock *lock)
414 {
415         int first;
416         ENTRY;
417         lock_res_and_lock(lock);
418         first = ldlm_lock_destroy_internal(lock);
419         unlock_res_and_lock(lock);
420
421         /* drop reference from hashtable only for first destroy */
422         if (first) {
423                 lu_ref_del(&lock->l_reference, "hash", lock);
424                 LDLM_LOCK_RELEASE(lock);
425         }
426         EXIT;
427 }
428
429 /**
430  * Destroys a LDLM lock \a lock that is already locked.
431  */
432 void ldlm_lock_destroy_nolock(struct ldlm_lock *lock)
433 {
434         int first;
435         ENTRY;
436         first = ldlm_lock_destroy_internal(lock);
437         /* drop reference from hashtable only for first destroy */
438         if (first) {
439                 lu_ref_del(&lock->l_reference, "hash", lock);
440                 LDLM_LOCK_RELEASE(lock);
441         }
442         EXIT;
443 }
444
445 /* this is called by portals_handle2object with the handle lock taken */
446 static void lock_handle_addref(void *lock)
447 {
448         LDLM_LOCK_GET((struct ldlm_lock *)lock);
449 }
450
451 static void lock_handle_free(void *lock, int size)
452 {
453         LASSERT(size == sizeof(struct ldlm_lock));
454         OBD_SLAB_FREE(lock, ldlm_lock_slab, size);
455 }
456
457 struct portals_handle_ops lock_handle_ops = {
458         .hop_addref = lock_handle_addref,
459         .hop_free   = lock_handle_free,
460 };
461
462 /**
463  *
464  * Allocate and initialize new lock structure.
465  *
466  * usage: pass in a resource on which you have done ldlm_resource_get
467  *        new lock will take over the refcount.
468  * returns: lock with refcount 2 - one for current caller and one for remote
469  */
470 static struct ldlm_lock *ldlm_lock_new(struct ldlm_resource *resource)
471 {
472         struct ldlm_lock *lock;
473         ENTRY;
474
475         if (resource == NULL)
476                 LBUG();
477
478         OBD_SLAB_ALLOC_PTR_GFP(lock, ldlm_lock_slab, CFS_ALLOC_IO);
479         if (lock == NULL)
480                 RETURN(NULL);
481
482         spin_lock_init(&lock->l_lock);
483         lock->l_resource = resource;
484         lu_ref_add(&resource->lr_reference, "lock", lock);
485
486         cfs_atomic_set(&lock->l_refc, 2);
487         CFS_INIT_LIST_HEAD(&lock->l_res_link);
488         CFS_INIT_LIST_HEAD(&lock->l_lru);
489         CFS_INIT_LIST_HEAD(&lock->l_pending_chain);
490         CFS_INIT_LIST_HEAD(&lock->l_bl_ast);
491         CFS_INIT_LIST_HEAD(&lock->l_cp_ast);
492         CFS_INIT_LIST_HEAD(&lock->l_rk_ast);
493         cfs_waitq_init(&lock->l_waitq);
494         lock->l_blocking_lock = NULL;
495         CFS_INIT_LIST_HEAD(&lock->l_sl_mode);
496         CFS_INIT_LIST_HEAD(&lock->l_sl_policy);
497         CFS_INIT_HLIST_NODE(&lock->l_exp_hash);
498         CFS_INIT_HLIST_NODE(&lock->l_exp_flock_hash);
499
500         lprocfs_counter_incr(ldlm_res_to_ns(resource)->ns_stats,
501                              LDLM_NSS_LOCKS);
502         CFS_INIT_LIST_HEAD(&lock->l_handle.h_link);
503         class_handle_hash(&lock->l_handle, &lock_handle_ops);
504
505         lu_ref_init(&lock->l_reference);
506         lu_ref_add(&lock->l_reference, "hash", lock);
507         lock->l_callback_timeout = 0;
508
509 #if LUSTRE_TRACKS_LOCK_EXP_REFS
510         CFS_INIT_LIST_HEAD(&lock->l_exp_refs_link);
511         lock->l_exp_refs_nr = 0;
512         lock->l_exp_refs_target = NULL;
513 #endif
514         CFS_INIT_LIST_HEAD(&lock->l_exp_list);
515
516         RETURN(lock);
517 }
518
519 /**
520  * Moves LDLM lock \a lock to another resource.
521  * This is used on client when server returns some other lock than requested
522  * (typically as a result of intent operation)
523  */
524 int ldlm_lock_change_resource(struct ldlm_namespace *ns, struct ldlm_lock *lock,
525                               const struct ldlm_res_id *new_resid)
526 {
527         struct ldlm_resource *oldres = lock->l_resource;
528         struct ldlm_resource *newres;
529         int type;
530         ENTRY;
531
532         LASSERT(ns_is_client(ns));
533
534         lock_res_and_lock(lock);
535         if (memcmp(new_resid, &lock->l_resource->lr_name,
536                    sizeof(lock->l_resource->lr_name)) == 0) {
537                 /* Nothing to do */
538                 unlock_res_and_lock(lock);
539                 RETURN(0);
540         }
541
542         LASSERT(new_resid->name[0] != 0);
543
544         /* This function assumes that the lock isn't on any lists */
545         LASSERT(cfs_list_empty(&lock->l_res_link));
546
547         type = oldres->lr_type;
548         unlock_res_and_lock(lock);
549
550         newres = ldlm_resource_get(ns, NULL, new_resid, type, 1);
551         if (newres == NULL)
552                 RETURN(-ENOMEM);
553
554         lu_ref_add(&newres->lr_reference, "lock", lock);
555         /*
556          * To flip the lock from the old to the new resource, lock, oldres and
557          * newres have to be locked. Resource spin-locks are nested within
558          * lock->l_lock, and are taken in the memory address order to avoid
559          * dead-locks.
560          */
561         spin_lock(&lock->l_lock);
562         oldres = lock->l_resource;
563         if (oldres < newres) {
564                 lock_res(oldres);
565                 lock_res_nested(newres, LRT_NEW);
566         } else {
567                 lock_res(newres);
568                 lock_res_nested(oldres, LRT_NEW);
569         }
570         LASSERT(memcmp(new_resid, &oldres->lr_name,
571                        sizeof oldres->lr_name) != 0);
572         lock->l_resource = newres;
573         unlock_res(oldres);
574         unlock_res_and_lock(lock);
575
576         /* ...and the flowers are still standing! */
577         lu_ref_del(&oldres->lr_reference, "lock", lock);
578         ldlm_resource_putref(oldres);
579
580         RETURN(0);
581 }
582 EXPORT_SYMBOL(ldlm_lock_change_resource);
583
584 /** \defgroup ldlm_handles LDLM HANDLES
585  * Ways to get hold of locks without any addresses.
586  * @{
587  */
588
589 /**
590  * Fills in handle for LDLM lock \a lock into supplied \a lockh
591  * Does not take any references.
592  */
593 void ldlm_lock2handle(const struct ldlm_lock *lock, struct lustre_handle *lockh)
594 {
595         lockh->cookie = lock->l_handle.h_cookie;
596 }
597 EXPORT_SYMBOL(ldlm_lock2handle);
598
599 /**
600  * Obtain a lock reference by handle.
601  *
602  * if \a flags: atomically get the lock and set the flags.
603  *              Return NULL if flag already set
604  */
605 struct ldlm_lock *__ldlm_handle2lock(const struct lustre_handle *handle,
606                                      __u64 flags)
607 {
608         struct ldlm_lock *lock;
609         ENTRY;
610
611         LASSERT(handle);
612
613         lock = class_handle2object(handle->cookie);
614         if (lock == NULL)
615                 RETURN(NULL);
616
617         /* It's unlikely but possible that someone marked the lock as
618          * destroyed after we did handle2object on it */
619         if (flags == 0 && !lock->l_destroyed) {
620                 lu_ref_add(&lock->l_reference, "handle", cfs_current());
621                 RETURN(lock);
622         }
623
624         lock_res_and_lock(lock);
625
626         LASSERT(lock->l_resource != NULL);
627
628         lu_ref_add_atomic(&lock->l_reference, "handle", cfs_current());
629         if (unlikely(lock->l_destroyed)) {
630                 unlock_res_and_lock(lock);
631                 CDEBUG(D_INFO, "lock already destroyed: lock %p\n", lock);
632                 LDLM_LOCK_PUT(lock);
633                 RETURN(NULL);
634         }
635
636         if (flags && (lock->l_flags & flags)) {
637                 unlock_res_and_lock(lock);
638                 LDLM_LOCK_PUT(lock);
639                 RETURN(NULL);
640         }
641
642         if (flags)
643                 lock->l_flags |= flags;
644
645         unlock_res_and_lock(lock);
646         RETURN(lock);
647 }
648 EXPORT_SYMBOL(__ldlm_handle2lock);
649 /** @} ldlm_handles */
650
651 /**
652  * Fill in "on the wire" representation for given LDLM lock into supplied
653  * lock descriptor \a desc structure.
654  */
655 void ldlm_lock2desc(struct ldlm_lock *lock, struct ldlm_lock_desc *desc)
656 {
657         struct obd_export *exp = lock->l_export ?: lock->l_conn_export;
658
659         /* INODEBITS_INTEROP: If the other side does not support
660          * inodebits, reply with a plain lock descriptor. */
661         if ((lock->l_resource->lr_type == LDLM_IBITS) &&
662             (exp && !(exp_connect_flags(exp) & OBD_CONNECT_IBITS))) {
663                 /* Make sure all the right bits are set in this lock we
664                    are going to pass to client */
665                 LASSERTF(lock->l_policy_data.l_inodebits.bits ==
666                          (MDS_INODELOCK_LOOKUP | MDS_INODELOCK_UPDATE |
667                           MDS_INODELOCK_LAYOUT),
668                          "Inappropriate inode lock bits during "
669                          "conversion " LPU64 "\n",
670                          lock->l_policy_data.l_inodebits.bits);
671
672                 ldlm_res2desc(lock->l_resource, &desc->l_resource);
673                 desc->l_resource.lr_type = LDLM_PLAIN;
674
675                 /* Convert "new" lock mode to something old client can
676                    understand */
677                 if ((lock->l_req_mode == LCK_CR) ||
678                     (lock->l_req_mode == LCK_CW))
679                         desc->l_req_mode = LCK_PR;
680                 else
681                         desc->l_req_mode = lock->l_req_mode;
682                 if ((lock->l_granted_mode == LCK_CR) ||
683                     (lock->l_granted_mode == LCK_CW)) {
684                         desc->l_granted_mode = LCK_PR;
685                 } else {
686                         /* We never grant PW/EX locks to clients */
687                         LASSERT((lock->l_granted_mode != LCK_PW) &&
688                                 (lock->l_granted_mode != LCK_EX));
689                         desc->l_granted_mode = lock->l_granted_mode;
690                 }
691
692                 /* We do not copy policy here, because there is no
693                    policy for plain locks */
694         } else {
695                 ldlm_res2desc(lock->l_resource, &desc->l_resource);
696                 desc->l_req_mode = lock->l_req_mode;
697                 desc->l_granted_mode = lock->l_granted_mode;
698                 ldlm_convert_policy_to_wire(lock->l_resource->lr_type,
699                                             &lock->l_policy_data,
700                                             &desc->l_policy_data);
701         }
702 }
703 EXPORT_SYMBOL(ldlm_lock2desc);
704
705 /**
706  * Add a lock to list of conflicting locks to send AST to.
707  *
708  * Only add if we have not sent a blocking AST to the lock yet.
709  */
710 void ldlm_add_bl_work_item(struct ldlm_lock *lock, struct ldlm_lock *new,
711                            cfs_list_t *work_list)
712 {
713         if ((lock->l_flags & LDLM_FL_AST_SENT) == 0) {
714                 LDLM_DEBUG(lock, "lock incompatible; sending blocking AST.");
715                 lock->l_flags |= LDLM_FL_AST_SENT;
716                 /* If the enqueuing client said so, tell the AST recipient to
717                  * discard dirty data, rather than writing back. */
718                 if (new->l_flags & LDLM_AST_DISCARD_DATA)
719                         lock->l_flags |= LDLM_FL_DISCARD_DATA;
720                 LASSERT(cfs_list_empty(&lock->l_bl_ast));
721                 cfs_list_add(&lock->l_bl_ast, work_list);
722                 LDLM_LOCK_GET(lock);
723                 LASSERT(lock->l_blocking_lock == NULL);
724                 lock->l_blocking_lock = LDLM_LOCK_GET(new);
725         }
726 }
727
728 /**
729  * Add a lock to list of just granted locks to send completion AST to.
730  */
731 void ldlm_add_cp_work_item(struct ldlm_lock *lock, cfs_list_t *work_list)
732 {
733         if ((lock->l_flags & LDLM_FL_CP_REQD) == 0) {
734                 lock->l_flags |= LDLM_FL_CP_REQD;
735                 LDLM_DEBUG(lock, "lock granted; sending completion AST.");
736                 LASSERT(cfs_list_empty(&lock->l_cp_ast));
737                 cfs_list_add(&lock->l_cp_ast, work_list);
738                 LDLM_LOCK_GET(lock);
739         }
740 }
741
742 /**
743  * Aggregator function to add AST work items into a list. Determines
744  * what sort of an AST work needs to be done and calls the proper
745  * adding function.
746  * Must be called with lr_lock held.
747  */
748 void ldlm_add_ast_work_item(struct ldlm_lock *lock, struct ldlm_lock *new,
749                             cfs_list_t *work_list)
750 {
751         ENTRY;
752         check_res_locked(lock->l_resource);
753         if (new)
754                 ldlm_add_bl_work_item(lock, new, work_list);
755         else
756                 ldlm_add_cp_work_item(lock, work_list);
757         EXIT;
758 }
759
760 /**
761  * Add specified reader/writer reference to LDLM lock with handle \a lockh.
762  * r/w reference type is determined by \a mode
763  * Calls ldlm_lock_addref_internal.
764  */
765 void ldlm_lock_addref(struct lustre_handle *lockh, __u32 mode)
766 {
767         struct ldlm_lock *lock;
768
769         lock = ldlm_handle2lock(lockh);
770         LASSERT(lock != NULL);
771         ldlm_lock_addref_internal(lock, mode);
772         LDLM_LOCK_PUT(lock);
773 }
774 EXPORT_SYMBOL(ldlm_lock_addref);
775
776 /**
777  * Helper function.
778  * Add specified reader/writer reference to LDLM lock \a lock.
779  * r/w reference type is determined by \a mode
780  * Removes lock from LRU if it is there.
781  * Assumes the LDLM lock is already locked.
782  */
783 void ldlm_lock_addref_internal_nolock(struct ldlm_lock *lock, __u32 mode)
784 {
785         ldlm_lock_remove_from_lru(lock);
786         if (mode & (LCK_NL | LCK_CR | LCK_PR)) {
787                 lock->l_readers++;
788                 lu_ref_add_atomic(&lock->l_reference, "reader", lock);
789         }
790         if (mode & (LCK_EX | LCK_CW | LCK_PW | LCK_GROUP | LCK_COS)) {
791                 lock->l_writers++;
792                 lu_ref_add_atomic(&lock->l_reference, "writer", lock);
793         }
794         LDLM_LOCK_GET(lock);
795         lu_ref_add_atomic(&lock->l_reference, "user", lock);
796         LDLM_DEBUG(lock, "ldlm_lock_addref(%s)", ldlm_lockname[mode]);
797 }
798
799 /**
800  * Attempts to add reader/writer reference to a lock with handle \a lockh, and
801  * fails if lock is already LDLM_FL_CBPENDING or destroyed.
802  *
803  * \retval 0 success, lock was addref-ed
804  *
805  * \retval -EAGAIN lock is being canceled.
806  */
807 int ldlm_lock_addref_try(struct lustre_handle *lockh, __u32 mode)
808 {
809         struct ldlm_lock *lock;
810         int               result;
811
812         result = -EAGAIN;
813         lock = ldlm_handle2lock(lockh);
814         if (lock != NULL) {
815                 lock_res_and_lock(lock);
816                 if (lock->l_readers != 0 || lock->l_writers != 0 ||
817                     !(lock->l_flags & LDLM_FL_CBPENDING)) {
818                         ldlm_lock_addref_internal_nolock(lock, mode);
819                         result = 0;
820                 }
821                 unlock_res_and_lock(lock);
822                 LDLM_LOCK_PUT(lock);
823         }
824         return result;
825 }
826 EXPORT_SYMBOL(ldlm_lock_addref_try);
827
828 /**
829  * Add specified reader/writer reference to LDLM lock \a lock.
830  * Locks LDLM lock and calls ldlm_lock_addref_internal_nolock to do the work.
831  * Only called for local locks.
832  */
833 void ldlm_lock_addref_internal(struct ldlm_lock *lock, __u32 mode)
834 {
835         lock_res_and_lock(lock);
836         ldlm_lock_addref_internal_nolock(lock, mode);
837         unlock_res_and_lock(lock);
838 }
839
840 /**
841  * Removes reader/writer reference for LDLM lock \a lock.
842  * Assumes LDLM lock is already locked.
843  * only called in ldlm_flock_destroy and for local locks.
844  * Does NOT add lock to LRU if no r/w references left to accomodate flock locks
845  * that cannot be placed in LRU.
846  */
847 void ldlm_lock_decref_internal_nolock(struct ldlm_lock *lock, __u32 mode)
848 {
849         LDLM_DEBUG(lock, "ldlm_lock_decref(%s)", ldlm_lockname[mode]);
850         if (mode & (LCK_NL | LCK_CR | LCK_PR)) {
851                 LASSERT(lock->l_readers > 0);
852                 lu_ref_del(&lock->l_reference, "reader", lock);
853                 lock->l_readers--;
854         }
855         if (mode & (LCK_EX | LCK_CW | LCK_PW | LCK_GROUP | LCK_COS)) {
856                 LASSERT(lock->l_writers > 0);
857                 lu_ref_del(&lock->l_reference, "writer", lock);
858                 lock->l_writers--;
859         }
860
861         lu_ref_del(&lock->l_reference, "user", lock);
862         LDLM_LOCK_RELEASE(lock);    /* matches the LDLM_LOCK_GET() in addref */
863 }
864
865 /**
866  * Removes reader/writer reference for LDLM lock \a lock.
867  * Locks LDLM lock first.
868  * If the lock is determined to be client lock on a client and r/w refcount
869  * drops to zero and the lock is not blocked, the lock is added to LRU lock
870  * on the namespace.
871  * For blocked LDLM locks if r/w count drops to zero, blocking_ast is called.
872  */
873 void ldlm_lock_decref_internal(struct ldlm_lock *lock, __u32 mode)
874 {
875         struct ldlm_namespace *ns;
876         ENTRY;
877
878         lock_res_and_lock(lock);
879
880         ns = ldlm_lock_to_ns(lock);
881
882         ldlm_lock_decref_internal_nolock(lock, mode);
883
884         /* release lvb data for layout lock */
885         if (ns_is_client(ns) && !lock->l_readers && !lock->l_writers &&
886             ldlm_has_layout(lock) && lock->l_flags & LDLM_FL_LVB_READY) {
887                 /* this is the last user of a layout lock and stripe has
888                  * been set up, lvb is no longer used.
889                  * This may be a large amount of memory, so we should free it
890                  * when possible. */
891                 if (lock->l_lvb_data != NULL) {
892                         OBD_FREE_LARGE(lock->l_lvb_data, lock->l_lvb_len);
893                         lock->l_lvb_data = NULL;
894                         lock->l_lvb_len = 0;
895                 }
896         }
897
898         if (lock->l_flags & LDLM_FL_LOCAL &&
899             !lock->l_readers && !lock->l_writers) {
900                 /* If this is a local lock on a server namespace and this was
901                  * the last reference, cancel the lock. */
902                 CDEBUG(D_INFO, "forcing cancel of local lock\n");
903                 lock->l_flags |= LDLM_FL_CBPENDING;
904         }
905
906         if (!lock->l_readers && !lock->l_writers &&
907             (lock->l_flags & LDLM_FL_CBPENDING)) {
908                 /* If we received a blocked AST and this was the last reference,
909                  * run the callback. */
910                 if (lock->l_ns_srv && lock->l_export)
911                         CERROR("FL_CBPENDING set on non-local lock--just a "
912                                "warning\n");
913
914                 LDLM_DEBUG(lock, "final decref done on cbpending lock");
915
916                 LDLM_LOCK_GET(lock); /* dropped by bl thread */
917                 ldlm_lock_remove_from_lru(lock);
918                 unlock_res_and_lock(lock);
919
920                 if (lock->l_flags & LDLM_FL_FAIL_LOC)
921                         OBD_RACE(OBD_FAIL_LDLM_CP_BL_RACE);
922
923                 if ((lock->l_flags & LDLM_FL_ATOMIC_CB) ||
924                     ldlm_bl_to_thread_lock(ns, NULL, lock) != 0)
925                         ldlm_handle_bl_callback(ns, NULL, lock);
926         } else if (ns_is_client(ns) &&
927                    !lock->l_readers && !lock->l_writers &&
928                    !(lock->l_flags & LDLM_FL_NO_LRU) &&
929                    !(lock->l_flags & LDLM_FL_BL_AST)) {
930
931                 LDLM_DEBUG(lock, "add lock into lru list");
932
933                 /* If this is a client-side namespace and this was the last
934                  * reference, put it on the LRU. */
935                 ldlm_lock_add_to_lru(lock);
936                 unlock_res_and_lock(lock);
937
938                 if (lock->l_flags & LDLM_FL_FAIL_LOC)
939                         OBD_RACE(OBD_FAIL_LDLM_CP_BL_RACE);
940
941                 /* Call ldlm_cancel_lru() only if EARLY_CANCEL and LRU RESIZE
942                  * are not supported by the server, otherwise, it is done on
943                  * enqueue. */
944                 if (!exp_connect_cancelset(lock->l_conn_export) &&
945                     !ns_connect_lru_resize(ns))
946                         ldlm_cancel_lru(ns, 0, LCF_ASYNC, 0);
947         } else {
948                 LDLM_DEBUG(lock, "do not add lock into lru list");
949                 unlock_res_and_lock(lock);
950         }
951
952         EXIT;
953 }
954
955 /**
956  * Decrease reader/writer refcount for LDLM lock with handle \a lockh
957  */
958 void ldlm_lock_decref(struct lustre_handle *lockh, __u32 mode)
959 {
960         struct ldlm_lock *lock = __ldlm_handle2lock(lockh, 0);
961         LASSERTF(lock != NULL, "Non-existing lock: "LPX64"\n", lockh->cookie);
962         ldlm_lock_decref_internal(lock, mode);
963         LDLM_LOCK_PUT(lock);
964 }
965 EXPORT_SYMBOL(ldlm_lock_decref);
966
967 /**
968  * Decrease reader/writer refcount for LDLM lock with handle
969  * \a lockh and mark it for subsequent cancellation once r/w refcount
970  * drops to zero instead of putting into LRU.
971  *
972  * Typical usage is for GROUP locks which we cannot allow to be cached.
973  */
974 void ldlm_lock_decref_and_cancel(struct lustre_handle *lockh, __u32 mode)
975 {
976         struct ldlm_lock *lock = __ldlm_handle2lock(lockh, 0);
977         ENTRY;
978
979         LASSERT(lock != NULL);
980
981         LDLM_DEBUG(lock, "ldlm_lock_decref(%s)", ldlm_lockname[mode]);
982         lock_res_and_lock(lock);
983         lock->l_flags |= LDLM_FL_CBPENDING;
984         unlock_res_and_lock(lock);
985         ldlm_lock_decref_internal(lock, mode);
986         LDLM_LOCK_PUT(lock);
987 }
988 EXPORT_SYMBOL(ldlm_lock_decref_and_cancel);
989
990 struct sl_insert_point {
991         cfs_list_t *res_link;
992         cfs_list_t *mode_link;
993         cfs_list_t *policy_link;
994 };
995
996 /**
997  * Finds a position to insert the new lock into granted lock list.
998  *
999  * Used for locks eligible for skiplist optimization.
1000  *
1001  * Parameters:
1002  *      queue [input]:  the granted list where search acts on;
1003  *      req [input]:    the lock whose position to be located;
1004  *      prev [output]:  positions within 3 lists to insert @req to
1005  * Return Value:
1006  *      filled @prev
1007  * NOTE: called by
1008  *  - ldlm_grant_lock_with_skiplist
1009  */
1010 static void search_granted_lock(cfs_list_t *queue,
1011                                 struct ldlm_lock *req,
1012                                 struct sl_insert_point *prev)
1013 {
1014         cfs_list_t *tmp;
1015         struct ldlm_lock *lock, *mode_end, *policy_end;
1016         ENTRY;
1017
1018         cfs_list_for_each(tmp, queue) {
1019                 lock = cfs_list_entry(tmp, struct ldlm_lock, l_res_link);
1020
1021                 mode_end = cfs_list_entry(lock->l_sl_mode.prev,
1022                                           struct ldlm_lock, l_sl_mode);
1023
1024                 if (lock->l_req_mode != req->l_req_mode) {
1025                         /* jump to last lock of mode group */
1026                         tmp = &mode_end->l_res_link;
1027                         continue;
1028                 }
1029
1030                 /* suitable mode group is found */
1031                 if (lock->l_resource->lr_type == LDLM_PLAIN) {
1032                         /* insert point is last lock of the mode group */
1033                         prev->res_link = &mode_end->l_res_link;
1034                         prev->mode_link = &mode_end->l_sl_mode;
1035                         prev->policy_link = &req->l_sl_policy;
1036                         EXIT;
1037                         return;
1038                 } else if (lock->l_resource->lr_type == LDLM_IBITS) {
1039                         for (;;) {
1040                                 policy_end =
1041                                         cfs_list_entry(lock->l_sl_policy.prev,
1042                                                        struct ldlm_lock,
1043                                                        l_sl_policy);
1044
1045                                 if (lock->l_policy_data.l_inodebits.bits ==
1046                                     req->l_policy_data.l_inodebits.bits) {
1047                                         /* insert point is last lock of
1048                                          * the policy group */
1049                                         prev->res_link =
1050                                                 &policy_end->l_res_link;
1051                                         prev->mode_link =
1052                                                 &policy_end->l_sl_mode;
1053                                         prev->policy_link =
1054                                                 &policy_end->l_sl_policy;
1055                                         EXIT;
1056                                         return;
1057                                 }
1058
1059                                 if (policy_end == mode_end)
1060                                         /* done with mode group */
1061                                         break;
1062
1063                                 /* go to next policy group within mode group */
1064                                 tmp = policy_end->l_res_link.next;
1065                                 lock = cfs_list_entry(tmp, struct ldlm_lock,
1066                                                       l_res_link);
1067                         }  /* loop over policy groups within the mode group */
1068
1069                         /* insert point is last lock of the mode group,
1070                          * new policy group is started */
1071                         prev->res_link = &mode_end->l_res_link;
1072                         prev->mode_link = &mode_end->l_sl_mode;
1073                         prev->policy_link = &req->l_sl_policy;
1074                         EXIT;
1075                         return;
1076                 } else {
1077                         LDLM_ERROR(lock,"is not LDLM_PLAIN or LDLM_IBITS lock");
1078                         LBUG();
1079                 }
1080         }
1081
1082         /* insert point is last lock on the queue,
1083          * new mode group and new policy group are started */
1084         prev->res_link = queue->prev;
1085         prev->mode_link = &req->l_sl_mode;
1086         prev->policy_link = &req->l_sl_policy;
1087         EXIT;
1088         return;
1089 }
1090
1091 /**
1092  * Add a lock into resource granted list after a position described by
1093  * \a prev.
1094  */
1095 static void ldlm_granted_list_add_lock(struct ldlm_lock *lock,
1096                                        struct sl_insert_point *prev)
1097 {
1098         struct ldlm_resource *res = lock->l_resource;
1099         ENTRY;
1100
1101         check_res_locked(res);
1102
1103         ldlm_resource_dump(D_INFO, res);
1104         LDLM_DEBUG(lock, "About to add lock:");
1105
1106         if (lock->l_destroyed) {
1107                 CDEBUG(D_OTHER, "Lock destroyed, not adding to resource\n");
1108                 return;
1109         }
1110
1111         LASSERT(cfs_list_empty(&lock->l_res_link));
1112         LASSERT(cfs_list_empty(&lock->l_sl_mode));
1113         LASSERT(cfs_list_empty(&lock->l_sl_policy));
1114
1115         /*
1116          * lock->link == prev->link means lock is first starting the group.
1117          * Don't re-add to itself to suppress kernel warnings.
1118          */
1119         if (&lock->l_res_link != prev->res_link)
1120                 cfs_list_add(&lock->l_res_link, prev->res_link);
1121         if (&lock->l_sl_mode != prev->mode_link)
1122                 cfs_list_add(&lock->l_sl_mode, prev->mode_link);
1123         if (&lock->l_sl_policy != prev->policy_link)
1124                 cfs_list_add(&lock->l_sl_policy, prev->policy_link);
1125
1126         EXIT;
1127 }
1128
1129 /**
1130  * Add a lock to granted list on a resource maintaining skiplist
1131  * correctness.
1132  */
1133 static void ldlm_grant_lock_with_skiplist(struct ldlm_lock *lock)
1134 {
1135         struct sl_insert_point prev;
1136         ENTRY;
1137
1138         LASSERT(lock->l_req_mode == lock->l_granted_mode);
1139
1140         search_granted_lock(&lock->l_resource->lr_granted, lock, &prev);
1141         ldlm_granted_list_add_lock(lock, &prev);
1142         EXIT;
1143 }
1144
1145 /**
1146  * Perform lock granting bookkeeping.
1147  *
1148  * Includes putting the lock into granted list and updating lock mode.
1149  * NOTE: called by
1150  *  - ldlm_lock_enqueue
1151  *  - ldlm_reprocess_queue
1152  *  - ldlm_lock_convert
1153  *
1154  * must be called with lr_lock held
1155  */
1156 void ldlm_grant_lock(struct ldlm_lock *lock, cfs_list_t *work_list)
1157 {
1158         struct ldlm_resource *res = lock->l_resource;
1159         ENTRY;
1160
1161         check_res_locked(res);
1162
1163         lock->l_granted_mode = lock->l_req_mode;
1164         if (res->lr_type == LDLM_PLAIN || res->lr_type == LDLM_IBITS)
1165                 ldlm_grant_lock_with_skiplist(lock);
1166         else if (res->lr_type == LDLM_EXTENT)
1167                 ldlm_extent_add_lock(res, lock);
1168         else
1169                 ldlm_resource_add_lock(res, &res->lr_granted, lock);
1170
1171         if (lock->l_granted_mode < res->lr_most_restr)
1172                 res->lr_most_restr = lock->l_granted_mode;
1173
1174         if (work_list && lock->l_completion_ast != NULL)
1175                 ldlm_add_ast_work_item(lock, NULL, work_list);
1176
1177         ldlm_pool_add(&ldlm_res_to_ns(res)->ns_pool, lock);
1178         EXIT;
1179 }
1180
1181 /**
1182  * Search for a lock with given properties in a queue.
1183  *
1184  * \retval a referenced lock or NULL.  See the flag descriptions below, in the
1185  * comment above ldlm_lock_match
1186  */
1187 static struct ldlm_lock *search_queue(cfs_list_t *queue,
1188                                       ldlm_mode_t *mode,
1189                                       ldlm_policy_data_t *policy,
1190                                       struct ldlm_lock *old_lock,
1191                                       __u64 flags, int unref)
1192 {
1193         struct ldlm_lock *lock;
1194         cfs_list_t       *tmp;
1195
1196         cfs_list_for_each(tmp, queue) {
1197                 ldlm_mode_t match;
1198
1199                 lock = cfs_list_entry(tmp, struct ldlm_lock, l_res_link);
1200
1201                 if (lock == old_lock)
1202                         break;
1203
1204                 /* llite sometimes wants to match locks that will be
1205                  * canceled when their users drop, but we allow it to match
1206                  * if it passes in CBPENDING and the lock still has users.
1207                  * this is generally only going to be used by children
1208                  * whose parents already hold a lock so forward progress
1209                  * can still happen. */
1210                 if (lock->l_flags & LDLM_FL_CBPENDING &&
1211                     !(flags & LDLM_FL_CBPENDING))
1212                         continue;
1213                 if (!unref && lock->l_flags & LDLM_FL_CBPENDING &&
1214                     lock->l_readers == 0 && lock->l_writers == 0)
1215                         continue;
1216
1217                 if (!(lock->l_req_mode & *mode))
1218                         continue;
1219                 match = lock->l_req_mode;
1220
1221                 if (lock->l_resource->lr_type == LDLM_EXTENT &&
1222                     (lock->l_policy_data.l_extent.start >
1223                      policy->l_extent.start ||
1224                      lock->l_policy_data.l_extent.end < policy->l_extent.end))
1225                         continue;
1226
1227                 if (unlikely(match == LCK_GROUP) &&
1228                     lock->l_resource->lr_type == LDLM_EXTENT &&
1229                     lock->l_policy_data.l_extent.gid != policy->l_extent.gid)
1230                         continue;
1231
1232                 /* We match if we have existing lock with same or wider set
1233                    of bits. */
1234                 if (lock->l_resource->lr_type == LDLM_IBITS &&
1235                      ((lock->l_policy_data.l_inodebits.bits &
1236                       policy->l_inodebits.bits) !=
1237                       policy->l_inodebits.bits))
1238                         continue;
1239
1240                 if (!unref &&
1241                     (lock->l_destroyed || lock->l_flags & LDLM_FL_FAILED ||
1242                      lock->l_failed))
1243                         continue;
1244
1245                 if ((flags & LDLM_FL_LOCAL_ONLY) &&
1246                     !(lock->l_flags & LDLM_FL_LOCAL))
1247                         continue;
1248
1249                 if (flags & LDLM_FL_TEST_LOCK) {
1250                         LDLM_LOCK_GET(lock);
1251                         ldlm_lock_touch_in_lru(lock);
1252                 } else {
1253                         ldlm_lock_addref_internal_nolock(lock, match);
1254                 }
1255                 *mode = match;
1256                 return lock;
1257         }
1258
1259         return NULL;
1260 }
1261
1262 void ldlm_lock_fail_match_locked(struct ldlm_lock *lock)
1263 {
1264         if (!lock->l_failed) {
1265                 lock->l_failed = 1;
1266                 cfs_waitq_broadcast(&lock->l_waitq);
1267         }
1268 }
1269 EXPORT_SYMBOL(ldlm_lock_fail_match_locked);
1270
1271 void ldlm_lock_fail_match(struct ldlm_lock *lock)
1272 {
1273         lock_res_and_lock(lock);
1274         ldlm_lock_fail_match_locked(lock);
1275         unlock_res_and_lock(lock);
1276 }
1277 EXPORT_SYMBOL(ldlm_lock_fail_match);
1278
1279 /**
1280  * Mark lock as "matchable" by OST.
1281  *
1282  * Used to prevent certain races in LOV/OSC where the lock is granted, but LVB
1283  * is not yet valid.
1284  * Assumes LDLM lock is already locked.
1285  */
1286 void ldlm_lock_allow_match_locked(struct ldlm_lock *lock)
1287 {
1288         lock->l_flags |= LDLM_FL_LVB_READY;
1289         cfs_waitq_broadcast(&lock->l_waitq);
1290 }
1291 EXPORT_SYMBOL(ldlm_lock_allow_match_locked);
1292
1293 /**
1294  * Mark lock as "matchable" by OST.
1295  * Locks the lock and then \see ldlm_lock_allow_match_locked
1296  */
1297 void ldlm_lock_allow_match(struct ldlm_lock *lock)
1298 {
1299         lock_res_and_lock(lock);
1300         ldlm_lock_allow_match_locked(lock);
1301         unlock_res_and_lock(lock);
1302 }
1303 EXPORT_SYMBOL(ldlm_lock_allow_match);
1304
1305 /**
1306  * Attempt to find a lock with specified properties.
1307  *
1308  * Typically returns a reference to matched lock unless LDLM_FL_TEST_LOCK is
1309  * set in \a flags
1310  *
1311  * Can be called in two ways:
1312  *
1313  * If 'ns' is NULL, then lockh describes an existing lock that we want to look
1314  * for a duplicate of.
1315  *
1316  * Otherwise, all of the fields must be filled in, to match against.
1317  *
1318  * If 'flags' contains LDLM_FL_LOCAL_ONLY, then only match local locks on the
1319  *     server (ie, connh is NULL)
1320  * If 'flags' contains LDLM_FL_BLOCK_GRANTED, then only locks on the granted
1321  *     list will be considered
1322  * If 'flags' contains LDLM_FL_CBPENDING, then locks that have been marked
1323  *     to be canceled can still be matched as long as they still have reader
1324  *     or writer refernces
1325  * If 'flags' contains LDLM_FL_TEST_LOCK, then don't actually reference a lock,
1326  *     just tell us if we would have matched.
1327  *
1328  * \retval 1 if it finds an already-existing lock that is compatible; in this
1329  * case, lockh is filled in with a addref()ed lock
1330  *
1331  * We also check security context, and if that fails we simply return 0 (to
1332  * keep caller code unchanged), the context failure will be discovered by
1333  * caller sometime later.
1334  */
1335 ldlm_mode_t ldlm_lock_match(struct ldlm_namespace *ns, __u64 flags,
1336                             const struct ldlm_res_id *res_id, ldlm_type_t type,
1337                             ldlm_policy_data_t *policy, ldlm_mode_t mode,
1338                             struct lustre_handle *lockh, int unref)
1339 {
1340         struct ldlm_resource *res;
1341         struct ldlm_lock *lock, *old_lock = NULL;
1342         int rc = 0;
1343         ENTRY;
1344
1345         if (ns == NULL) {
1346                 old_lock = ldlm_handle2lock(lockh);
1347                 LASSERT(old_lock);
1348
1349                 ns = ldlm_lock_to_ns(old_lock);
1350                 res_id = &old_lock->l_resource->lr_name;
1351                 type = old_lock->l_resource->lr_type;
1352                 mode = old_lock->l_req_mode;
1353         }
1354
1355         res = ldlm_resource_get(ns, NULL, res_id, type, 0);
1356         if (res == NULL) {
1357                 LASSERT(old_lock == NULL);
1358                 RETURN(0);
1359         }
1360
1361         LDLM_RESOURCE_ADDREF(res);
1362         lock_res(res);
1363
1364         lock = search_queue(&res->lr_granted, &mode, policy, old_lock,
1365                             flags, unref);
1366         if (lock != NULL)
1367                 GOTO(out, rc = 1);
1368         if (flags & LDLM_FL_BLOCK_GRANTED)
1369                 GOTO(out, rc = 0);
1370         lock = search_queue(&res->lr_converting, &mode, policy, old_lock,
1371                             flags, unref);
1372         if (lock != NULL)
1373                 GOTO(out, rc = 1);
1374         lock = search_queue(&res->lr_waiting, &mode, policy, old_lock,
1375                             flags, unref);
1376         if (lock != NULL)
1377                 GOTO(out, rc = 1);
1378
1379         EXIT;
1380  out:
1381         unlock_res(res);
1382         LDLM_RESOURCE_DELREF(res);
1383         ldlm_resource_putref(res);
1384
1385         if (lock) {
1386                 ldlm_lock2handle(lock, lockh);
1387                 if ((flags & LDLM_FL_LVB_READY) &&
1388                     (!(lock->l_flags & LDLM_FL_LVB_READY))) {
1389                         struct l_wait_info lwi;
1390                         if (lock->l_completion_ast) {
1391                                 int err = lock->l_completion_ast(lock,
1392                                                           LDLM_FL_WAIT_NOREPROC,
1393                                                                  NULL);
1394                                 if (err) {
1395                                         if (flags & LDLM_FL_TEST_LOCK)
1396                                                 LDLM_LOCK_RELEASE(lock);
1397                                         else
1398                                                 ldlm_lock_decref_internal(lock,
1399                                                                           mode);
1400                                         rc = 0;
1401                                         goto out2;
1402                                 }
1403                         }
1404
1405                         lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(obd_timeout),
1406                                                NULL, LWI_ON_SIGNAL_NOOP, NULL);
1407
1408                         /* XXX FIXME see comment on CAN_MATCH in lustre_dlm.h */
1409                         l_wait_event(lock->l_waitq,
1410                                      lock->l_flags & LDLM_FL_LVB_READY ||
1411                                      lock->l_destroyed || lock->l_failed,
1412                                      &lwi);
1413                         if (!(lock->l_flags & LDLM_FL_LVB_READY)) {
1414                                 if (flags & LDLM_FL_TEST_LOCK)
1415                                         LDLM_LOCK_RELEASE(lock);
1416                                 else
1417                                         ldlm_lock_decref_internal(lock, mode);
1418                                 rc = 0;
1419                         }
1420                 }
1421         }
1422  out2:
1423         if (rc) {
1424                 LDLM_DEBUG(lock, "matched ("LPU64" "LPU64")",
1425                            (type == LDLM_PLAIN || type == LDLM_IBITS) ?
1426                                 res_id->name[2] : policy->l_extent.start,
1427                            (type == LDLM_PLAIN || type == LDLM_IBITS) ?
1428                                 res_id->name[3] : policy->l_extent.end);
1429
1430                 /* check user's security context */
1431                 if (lock->l_conn_export &&
1432                     sptlrpc_import_check_ctx(
1433                                 class_exp2cliimp(lock->l_conn_export))) {
1434                         if (!(flags & LDLM_FL_TEST_LOCK))
1435                                 ldlm_lock_decref_internal(lock, mode);
1436                         rc = 0;
1437                 }
1438
1439                 if (flags & LDLM_FL_TEST_LOCK)
1440                         LDLM_LOCK_RELEASE(lock);
1441
1442         } else if (!(flags & LDLM_FL_TEST_LOCK)) {/*less verbose for test-only*/
1443                 LDLM_DEBUG_NOLOCK("not matched ns %p type %u mode %u res "
1444                                   LPU64"/"LPU64" ("LPU64" "LPU64")", ns,
1445                                   type, mode, res_id->name[0], res_id->name[1],
1446                                   (type == LDLM_PLAIN || type == LDLM_IBITS) ?
1447                                         res_id->name[2] :policy->l_extent.start,
1448                                   (type == LDLM_PLAIN || type == LDLM_IBITS) ?
1449                                         res_id->name[3] : policy->l_extent.end);
1450         }
1451         if (old_lock)
1452                 LDLM_LOCK_PUT(old_lock);
1453
1454         return rc ? mode : 0;
1455 }
1456 EXPORT_SYMBOL(ldlm_lock_match);
1457
1458 ldlm_mode_t ldlm_revalidate_lock_handle(struct lustre_handle *lockh,
1459                                         __u64 *bits)
1460 {
1461         struct ldlm_lock *lock;
1462         ldlm_mode_t mode = 0;
1463         ENTRY;
1464
1465         lock = ldlm_handle2lock(lockh);
1466         if (lock != NULL) {
1467                 lock_res_and_lock(lock);
1468                 if (lock->l_destroyed || lock->l_flags & LDLM_FL_FAILED ||
1469                     lock->l_failed)
1470                         GOTO(out, mode);
1471
1472                 if (lock->l_flags & LDLM_FL_CBPENDING &&
1473                     lock->l_readers == 0 && lock->l_writers == 0)
1474                         GOTO(out, mode);
1475
1476                 if (bits)
1477                         *bits = lock->l_policy_data.l_inodebits.bits;
1478                 mode = lock->l_granted_mode;
1479                 ldlm_lock_addref_internal_nolock(lock, mode);
1480         }
1481
1482         EXIT;
1483
1484 out:
1485         if (lock != NULL) {
1486                 unlock_res_and_lock(lock);
1487                 LDLM_LOCK_PUT(lock);
1488         }
1489         return mode;
1490 }
1491 EXPORT_SYMBOL(ldlm_revalidate_lock_handle);
1492
1493 /** The caller must guarantee that the buffer is large enough. */
1494 int ldlm_fill_lvb(struct ldlm_lock *lock, struct req_capsule *pill,
1495                   enum req_location loc, void *data, int size)
1496 {
1497         void *lvb;
1498         ENTRY;
1499
1500         LASSERT(data != NULL);
1501         LASSERT(size >= 0);
1502
1503         switch (lock->l_lvb_type) {
1504         case LVB_T_OST:
1505                 if (size == sizeof(struct ost_lvb)) {
1506                         if (loc == RCL_CLIENT)
1507                                 lvb = req_capsule_client_swab_get(pill,
1508                                                 &RMF_DLM_LVB,
1509                                                 lustre_swab_ost_lvb);
1510                         else
1511                                 lvb = req_capsule_server_swab_get(pill,
1512                                                 &RMF_DLM_LVB,
1513                                                 lustre_swab_ost_lvb);
1514                         if (unlikely(lvb == NULL)) {
1515                                 LDLM_ERROR(lock, "no LVB");
1516                                 RETURN(-EPROTO);
1517                         }
1518
1519                         memcpy(data, lvb, size);
1520                 } else if (size == sizeof(struct ost_lvb_v1)) {
1521                         struct ost_lvb *olvb = data;
1522
1523                         if (loc == RCL_CLIENT)
1524                                 lvb = req_capsule_client_swab_get(pill,
1525                                                 &RMF_DLM_LVB,
1526                                                 lustre_swab_ost_lvb_v1);
1527                         else
1528                                 lvb = req_capsule_server_sized_swab_get(pill,
1529                                                 &RMF_DLM_LVB, size,
1530                                                 lustre_swab_ost_lvb_v1);
1531                         if (unlikely(lvb == NULL)) {
1532                                 LDLM_ERROR(lock, "no LVB");
1533                                 RETURN(-EPROTO);
1534                         }
1535
1536                         memcpy(data, lvb, size);
1537                         olvb->lvb_mtime_ns = 0;
1538                         olvb->lvb_atime_ns = 0;
1539                         olvb->lvb_ctime_ns = 0;
1540                 } else {
1541                         LDLM_ERROR(lock, "Replied unexpected ost LVB size %d",
1542                                    size);
1543                         RETURN(-EINVAL);
1544                 }
1545                 break;
1546         case LVB_T_LQUOTA:
1547                 if (size == sizeof(struct lquota_lvb)) {
1548                         if (loc == RCL_CLIENT)
1549                                 lvb = req_capsule_client_swab_get(pill,
1550                                                 &RMF_DLM_LVB,
1551                                                 lustre_swab_lquota_lvb);
1552                         else
1553                                 lvb = req_capsule_server_swab_get(pill,
1554                                                 &RMF_DLM_LVB,
1555                                                 lustre_swab_lquota_lvb);
1556                         if (unlikely(lvb == NULL)) {
1557                                 LDLM_ERROR(lock, "no LVB");
1558                                 RETURN(-EPROTO);
1559                         }
1560
1561                         memcpy(data, lvb, size);
1562                 } else {
1563                         LDLM_ERROR(lock, "Replied unexpected lquota LVB size %d",
1564                                    size);
1565                         RETURN(-EINVAL);
1566                 }
1567                 break;
1568         case LVB_T_LAYOUT:
1569                 if (size == 0)
1570                         break;
1571
1572                 if (loc == RCL_CLIENT)
1573                         lvb = req_capsule_client_get(pill, &RMF_DLM_LVB);
1574                 else
1575                         lvb = req_capsule_server_get(pill, &RMF_DLM_LVB);
1576                 if (unlikely(lvb == NULL)) {
1577                         LDLM_ERROR(lock, "no LVB");
1578                         RETURN(-EPROTO);
1579                 }
1580
1581                 memcpy(data, lvb, size);
1582                 break;
1583         default:
1584                 LDLM_ERROR(lock, "Unknown LVB type: %d\n", lock->l_lvb_type);
1585                 libcfs_debug_dumpstack(NULL);
1586                 RETURN(-EINVAL);
1587         }
1588
1589         RETURN(0);
1590 }
1591
1592 /**
1593  * Create and fill in new LDLM lock with specified properties.
1594  * Returns a referenced lock
1595  */
1596 struct ldlm_lock *ldlm_lock_create(struct ldlm_namespace *ns,
1597                                    const struct ldlm_res_id *res_id,
1598                                    ldlm_type_t type,
1599                                    ldlm_mode_t mode,
1600                                    const struct ldlm_callback_suite *cbs,
1601                                    void *data, __u32 lvb_len,
1602                                    enum lvb_type lvb_type)
1603 {
1604         struct ldlm_lock *lock;
1605         struct ldlm_resource *res;
1606         ENTRY;
1607
1608         res = ldlm_resource_get(ns, NULL, res_id, type, 1);
1609         if (res == NULL)
1610                 RETURN(NULL);
1611
1612         lock = ldlm_lock_new(res);
1613
1614         if (lock == NULL)
1615                 RETURN(NULL);
1616
1617         lock->l_req_mode = mode;
1618         lock->l_ast_data = data;
1619         lock->l_pid = cfs_curproc_pid();
1620         lock->l_ns_srv = !!ns_is_server(ns);
1621         if (cbs) {
1622                 lock->l_blocking_ast = cbs->lcs_blocking;
1623                 lock->l_completion_ast = cbs->lcs_completion;
1624                 lock->l_glimpse_ast = cbs->lcs_glimpse;
1625                 lock->l_weigh_ast = cbs->lcs_weigh;
1626         }
1627
1628         lock->l_tree_node = NULL;
1629         /* if this is the extent lock, allocate the interval tree node */
1630         if (type == LDLM_EXTENT) {
1631                 if (ldlm_interval_alloc(lock) == NULL)
1632                         GOTO(out, 0);
1633         }
1634
1635         if (lvb_len) {
1636                 lock->l_lvb_len = lvb_len;
1637                 OBD_ALLOC(lock->l_lvb_data, lvb_len);
1638                 if (lock->l_lvb_data == NULL)
1639                         GOTO(out, 0);
1640         }
1641
1642         lock->l_lvb_type = lvb_type;
1643         if (OBD_FAIL_CHECK(OBD_FAIL_LDLM_NEW_LOCK))
1644                 GOTO(out, 0);
1645
1646         RETURN(lock);
1647
1648 out:
1649         ldlm_lock_destroy(lock);
1650         LDLM_LOCK_RELEASE(lock);
1651         return NULL;
1652 }
1653
1654 /**
1655  * Enqueue (request) a lock.
1656  *
1657  * Does not block. As a result of enqueue the lock would be put
1658  * into granted or waiting list.
1659  *
1660  * If namespace has intent policy sent and the lock has LDLM_FL_HAS_INTENT flag
1661  * set, skip all the enqueueing and delegate lock processing to intent policy
1662  * function.
1663  */
1664 ldlm_error_t ldlm_lock_enqueue(struct ldlm_namespace *ns,
1665                                struct ldlm_lock **lockp,
1666                                void *cookie, __u64 *flags)
1667 {
1668         struct ldlm_lock *lock = *lockp;
1669         struct ldlm_resource *res = lock->l_resource;
1670         int local = ns_is_client(ldlm_res_to_ns(res));
1671 #ifdef HAVE_SERVER_SUPPORT
1672         ldlm_processing_policy policy;
1673 #endif
1674         ldlm_error_t rc = ELDLM_OK;
1675         struct ldlm_interval *node = NULL;
1676         ENTRY;
1677
1678         lock->l_last_activity = cfs_time_current_sec();
1679         /* policies are not executed on the client or during replay */
1680         if ((*flags & (LDLM_FL_HAS_INTENT|LDLM_FL_REPLAY)) == LDLM_FL_HAS_INTENT
1681             && !local && ns->ns_policy) {
1682                 rc = ns->ns_policy(ns, lockp, cookie, lock->l_req_mode, *flags,
1683                                    NULL);
1684                 if (rc == ELDLM_LOCK_REPLACED) {
1685                         /* The lock that was returned has already been granted,
1686                          * and placed into lockp.  If it's not the same as the
1687                          * one we passed in, then destroy the old one and our
1688                          * work here is done. */
1689                         if (lock != *lockp) {
1690                                 ldlm_lock_destroy(lock);
1691                                 LDLM_LOCK_RELEASE(lock);
1692                         }
1693                         *flags |= LDLM_FL_LOCK_CHANGED;
1694                         RETURN(0);
1695                 } else if (rc != ELDLM_OK ||
1696                            (rc == ELDLM_OK && (*flags & LDLM_FL_INTENT_ONLY))) {
1697                         ldlm_lock_destroy(lock);
1698                         RETURN(rc);
1699                 }
1700         }
1701
1702         /* For a replaying lock, it might be already in granted list. So
1703          * unlinking the lock will cause the interval node to be freed, we
1704          * have to allocate the interval node early otherwise we can't regrant
1705          * this lock in the future. - jay */
1706         if (!local && (*flags & LDLM_FL_REPLAY) && res->lr_type == LDLM_EXTENT)
1707                 OBD_SLAB_ALLOC_PTR_GFP(node, ldlm_interval_slab, CFS_ALLOC_IO);
1708
1709         lock_res_and_lock(lock);
1710         if (local && lock->l_req_mode == lock->l_granted_mode) {
1711                 /* The server returned a blocked lock, but it was granted
1712                  * before we got a chance to actually enqueue it.  We don't
1713                  * need to do anything else. */
1714                 *flags &= ~(LDLM_FL_BLOCK_GRANTED |
1715                             LDLM_FL_BLOCK_CONV | LDLM_FL_BLOCK_WAIT);
1716                 GOTO(out, ELDLM_OK);
1717         }
1718
1719         ldlm_resource_unlink_lock(lock);
1720         if (res->lr_type == LDLM_EXTENT && lock->l_tree_node == NULL) {
1721                 if (node == NULL) {
1722                         ldlm_lock_destroy_nolock(lock);
1723                         GOTO(out, rc = -ENOMEM);
1724                 }
1725
1726                 CFS_INIT_LIST_HEAD(&node->li_group);
1727                 ldlm_interval_attach(node, lock);
1728                 node = NULL;
1729         }
1730
1731         /* Some flags from the enqueue want to make it into the AST, via the
1732          * lock's l_flags. */
1733         lock->l_flags |= *flags & LDLM_AST_DISCARD_DATA;
1734
1735         /* This distinction between local lock trees is very important; a client
1736          * namespace only has information about locks taken by that client, and
1737          * thus doesn't have enough information to decide for itself if it can
1738          * be granted (below).  In this case, we do exactly what the server
1739          * tells us to do, as dictated by the 'flags'.
1740          *
1741          * We do exactly the same thing during recovery, when the server is
1742          * more or less trusting the clients not to lie.
1743          *
1744          * FIXME (bug 268): Detect obvious lies by checking compatibility in
1745          * granted/converting queues. */
1746         if (local) {
1747                 if (*flags & LDLM_FL_BLOCK_CONV)
1748                         ldlm_resource_add_lock(res, &res->lr_converting, lock);
1749                 else if (*flags & (LDLM_FL_BLOCK_WAIT | LDLM_FL_BLOCK_GRANTED))
1750                         ldlm_resource_add_lock(res, &res->lr_waiting, lock);
1751                 else
1752                         ldlm_grant_lock(lock, NULL);
1753                 GOTO(out, ELDLM_OK);
1754 #ifdef HAVE_SERVER_SUPPORT
1755         } else if (*flags & LDLM_FL_REPLAY) {
1756                 if (*flags & LDLM_FL_BLOCK_CONV) {
1757                         ldlm_resource_add_lock(res, &res->lr_converting, lock);
1758                         GOTO(out, ELDLM_OK);
1759                 } else if (*flags & LDLM_FL_BLOCK_WAIT) {
1760                         ldlm_resource_add_lock(res, &res->lr_waiting, lock);
1761                         GOTO(out, ELDLM_OK);
1762                 } else if (*flags & LDLM_FL_BLOCK_GRANTED) {
1763                         ldlm_grant_lock(lock, NULL);
1764                         GOTO(out, ELDLM_OK);
1765                 }
1766                 /* If no flags, fall through to normal enqueue path. */
1767         }
1768
1769         policy = ldlm_processing_policy_table[res->lr_type];
1770         policy(lock, flags, 1, &rc, NULL);
1771         GOTO(out, rc);
1772 #else
1773         } else {
1774                 CERROR("This is client-side-only module, cannot handle "
1775                        "LDLM_NAMESPACE_SERVER resource type lock.\n");
1776                 LBUG();
1777         }
1778 #endif
1779
1780 out:
1781         unlock_res_and_lock(lock);
1782         if (node)
1783                 OBD_SLAB_FREE(node, ldlm_interval_slab, sizeof(*node));
1784         return rc;
1785 }
1786
1787 #ifdef HAVE_SERVER_SUPPORT
1788 /**
1789  * Iterate through all waiting locks on a given resource queue and attempt to
1790  * grant them.
1791  *
1792  * Must be called with resource lock held.
1793  */
1794 int ldlm_reprocess_queue(struct ldlm_resource *res, cfs_list_t *queue,
1795                          cfs_list_t *work_list)
1796 {
1797         cfs_list_t *tmp, *pos;
1798         ldlm_processing_policy policy;
1799         __u64 flags;
1800         int rc = LDLM_ITER_CONTINUE;
1801         ldlm_error_t err;
1802         ENTRY;
1803
1804         check_res_locked(res);
1805
1806         policy = ldlm_processing_policy_table[res->lr_type];
1807         LASSERT(policy);
1808
1809         cfs_list_for_each_safe(tmp, pos, queue) {
1810                 struct ldlm_lock *pending;
1811                 pending = cfs_list_entry(tmp, struct ldlm_lock, l_res_link);
1812
1813                 CDEBUG(D_INFO, "Reprocessing lock %p\n", pending);
1814
1815                 flags = 0;
1816                 rc = policy(pending, &flags, 0, &err, work_list);
1817                 if (rc != LDLM_ITER_CONTINUE)
1818                         break;
1819         }
1820
1821         RETURN(rc);
1822 }
1823 #endif
1824
1825 /**
1826  * Process a call to blocking AST callback for a lock in ast_work list
1827  */
1828 static int
1829 ldlm_work_bl_ast_lock(struct ptlrpc_request_set *rqset, void *opaq)
1830 {
1831         struct ldlm_cb_set_arg *arg = opaq;
1832         struct ldlm_lock_desc   d;
1833         int                     rc;
1834         struct ldlm_lock       *lock;
1835         ENTRY;
1836
1837         if (cfs_list_empty(arg->list))
1838                 RETURN(-ENOENT);
1839
1840         lock = cfs_list_entry(arg->list->next, struct ldlm_lock, l_bl_ast);
1841
1842         /* nobody should touch l_bl_ast */
1843         lock_res_and_lock(lock);
1844         cfs_list_del_init(&lock->l_bl_ast);
1845
1846         LASSERT(lock->l_flags & LDLM_FL_AST_SENT);
1847         LASSERT(lock->l_bl_ast_run == 0);
1848         LASSERT(lock->l_blocking_lock);
1849         lock->l_bl_ast_run++;
1850         unlock_res_and_lock(lock);
1851
1852         ldlm_lock2desc(lock->l_blocking_lock, &d);
1853
1854         rc = lock->l_blocking_ast(lock, &d, (void *)arg, LDLM_CB_BLOCKING);
1855         LDLM_LOCK_RELEASE(lock->l_blocking_lock);
1856         lock->l_blocking_lock = NULL;
1857         LDLM_LOCK_RELEASE(lock);
1858
1859         RETURN(rc);
1860 }
1861
1862 /**
1863  * Process a call to completion AST callback for a lock in ast_work list
1864  */
1865 static int
1866 ldlm_work_cp_ast_lock(struct ptlrpc_request_set *rqset, void *opaq)
1867 {
1868         struct ldlm_cb_set_arg  *arg = opaq;
1869         int                      rc = 0;
1870         struct ldlm_lock        *lock;
1871         ldlm_completion_callback completion_callback;
1872         ENTRY;
1873
1874         if (cfs_list_empty(arg->list))
1875                 RETURN(-ENOENT);
1876
1877         lock = cfs_list_entry(arg->list->next, struct ldlm_lock, l_cp_ast);
1878
1879         /* It's possible to receive a completion AST before we've set
1880          * the l_completion_ast pointer: either because the AST arrived
1881          * before the reply, or simply because there's a small race
1882          * window between receiving the reply and finishing the local
1883          * enqueue. (bug 842)
1884          *
1885          * This can't happen with the blocking_ast, however, because we
1886          * will never call the local blocking_ast until we drop our
1887          * reader/writer reference, which we won't do until we get the
1888          * reply and finish enqueueing. */
1889
1890         /* nobody should touch l_cp_ast */
1891         lock_res_and_lock(lock);
1892         cfs_list_del_init(&lock->l_cp_ast);
1893         LASSERT(lock->l_flags & LDLM_FL_CP_REQD);
1894         /* save l_completion_ast since it can be changed by
1895          * mds_intent_policy(), see bug 14225 */
1896         completion_callback = lock->l_completion_ast;
1897         lock->l_flags &= ~LDLM_FL_CP_REQD;
1898         unlock_res_and_lock(lock);
1899
1900         if (completion_callback != NULL)
1901                 rc = completion_callback(lock, 0, (void *)arg);
1902         LDLM_LOCK_RELEASE(lock);
1903
1904         RETURN(rc);
1905 }
1906
1907 /**
1908  * Process a call to revocation AST callback for a lock in ast_work list
1909  */
1910 static int
1911 ldlm_work_revoke_ast_lock(struct ptlrpc_request_set *rqset, void *opaq)
1912 {
1913         struct ldlm_cb_set_arg *arg = opaq;
1914         struct ldlm_lock_desc   desc;
1915         int                     rc;
1916         struct ldlm_lock       *lock;
1917         ENTRY;
1918
1919         if (cfs_list_empty(arg->list))
1920                 RETURN(-ENOENT);
1921
1922         lock = cfs_list_entry(arg->list->next, struct ldlm_lock, l_rk_ast);
1923         cfs_list_del_init(&lock->l_rk_ast);
1924
1925         /* the desc just pretend to exclusive */
1926         ldlm_lock2desc(lock, &desc);
1927         desc.l_req_mode = LCK_EX;
1928         desc.l_granted_mode = 0;
1929
1930         rc = lock->l_blocking_ast(lock, &desc, (void*)arg, LDLM_CB_BLOCKING);
1931         LDLM_LOCK_RELEASE(lock);
1932
1933         RETURN(rc);
1934 }
1935
1936 /**
1937  * Process a call to glimpse AST callback for a lock in ast_work list
1938  */
1939 int ldlm_work_gl_ast_lock(struct ptlrpc_request_set *rqset, void *opaq)
1940 {
1941         struct ldlm_cb_set_arg          *arg = opaq;
1942         struct ldlm_glimpse_work        *gl_work;
1943         struct ldlm_lock                *lock;
1944         int                              rc = 0;
1945         ENTRY;
1946
1947         if (cfs_list_empty(arg->list))
1948                 RETURN(-ENOENT);
1949
1950         gl_work = cfs_list_entry(arg->list->next, struct ldlm_glimpse_work,
1951                                  gl_list);
1952         cfs_list_del_init(&gl_work->gl_list);
1953
1954         lock = gl_work->gl_lock;
1955
1956         /* transfer the glimpse descriptor to ldlm_cb_set_arg */
1957         arg->gl_desc = gl_work->gl_desc;
1958
1959         /* invoke the actual glimpse callback */
1960         if (lock->l_glimpse_ast(lock, (void*)arg) == 0)
1961                 rc = 1;
1962
1963         LDLM_LOCK_RELEASE(lock);
1964
1965         if ((gl_work->gl_flags & LDLM_GL_WORK_NOFREE) == 0)
1966                 OBD_FREE_PTR(gl_work);
1967
1968         RETURN(rc);
1969 }
1970
1971 /**
1972  * Process list of locks in need of ASTs being sent.
1973  *
1974  * Used on server to send multiple ASTs together instead of sending one by
1975  * one.
1976  */
1977 int ldlm_run_ast_work(struct ldlm_namespace *ns, cfs_list_t *rpc_list,
1978                       ldlm_desc_ast_t ast_type)
1979 {
1980         struct ldlm_cb_set_arg *arg;
1981         set_producer_func       work_ast_lock;
1982         int                     rc;
1983
1984         if (cfs_list_empty(rpc_list))
1985                 RETURN(0);
1986
1987         OBD_ALLOC_PTR(arg);
1988         if (arg == NULL)
1989                 RETURN(-ENOMEM);
1990
1991         cfs_atomic_set(&arg->restart, 0);
1992         arg->list = rpc_list;
1993
1994         switch (ast_type) {
1995                 case LDLM_WORK_BL_AST:
1996                         arg->type = LDLM_BL_CALLBACK;
1997                         work_ast_lock = ldlm_work_bl_ast_lock;
1998                         break;
1999                 case LDLM_WORK_CP_AST:
2000                         arg->type = LDLM_CP_CALLBACK;
2001                         work_ast_lock = ldlm_work_cp_ast_lock;
2002                         break;
2003                 case LDLM_WORK_REVOKE_AST:
2004                         arg->type = LDLM_BL_CALLBACK;
2005                         work_ast_lock = ldlm_work_revoke_ast_lock;
2006                         break;
2007                 case LDLM_WORK_GL_AST:
2008                         arg->type = LDLM_GL_CALLBACK;
2009                         work_ast_lock = ldlm_work_gl_ast_lock;
2010                         break;
2011                 default:
2012                         LBUG();
2013         }
2014
2015         /* We create a ptlrpc request set with flow control extension.
2016          * This request set will use the work_ast_lock function to produce new
2017          * requests and will send a new request each time one completes in order
2018          * to keep the number of requests in flight to ns_max_parallel_ast */
2019         arg->set = ptlrpc_prep_fcset(ns->ns_max_parallel_ast ? : UINT_MAX,
2020                                      work_ast_lock, arg);
2021         if (arg->set == NULL)
2022                 GOTO(out, rc = -ENOMEM);
2023
2024         ptlrpc_set_wait(arg->set);
2025         ptlrpc_set_destroy(arg->set);
2026
2027         rc = cfs_atomic_read(&arg->restart) ? -ERESTART : 0;
2028         GOTO(out, rc);
2029 out:
2030         OBD_FREE_PTR(arg);
2031         return rc;
2032 }
2033
2034 static int reprocess_one_queue(struct ldlm_resource *res, void *closure)
2035 {
2036         ldlm_reprocess_all(res);
2037         return LDLM_ITER_CONTINUE;
2038 }
2039
2040 static int ldlm_reprocess_res(cfs_hash_t *hs, cfs_hash_bd_t *bd,
2041                               cfs_hlist_node_t *hnode, void *arg)
2042 {
2043         struct ldlm_resource *res = cfs_hash_object(hs, hnode);
2044         int    rc;
2045
2046         rc = reprocess_one_queue(res, arg);
2047
2048         return rc == LDLM_ITER_STOP;
2049 }
2050
2051 /**
2052  * Iterate through all resources on a namespace attempting to grant waiting
2053  * locks.
2054  */
2055 void ldlm_reprocess_all_ns(struct ldlm_namespace *ns)
2056 {
2057         ENTRY;
2058
2059         if (ns != NULL) {
2060                 cfs_hash_for_each_nolock(ns->ns_rs_hash,
2061                                          ldlm_reprocess_res, NULL);
2062         }
2063         EXIT;
2064 }
2065 EXPORT_SYMBOL(ldlm_reprocess_all_ns);
2066
2067 /**
2068  * Try to grant all waiting locks on a resource.
2069  *
2070  * Calls ldlm_reprocess_queue on converting and waiting queues.
2071  *
2072  * Typically called after some resource locks are cancelled to see
2073  * if anything could be granted as a result of the cancellation.
2074  */
2075 void ldlm_reprocess_all(struct ldlm_resource *res)
2076 {
2077         CFS_LIST_HEAD(rpc_list);
2078
2079 #ifdef HAVE_SERVER_SUPPORT
2080         int rc;
2081         ENTRY;
2082         /* Local lock trees don't get reprocessed. */
2083         if (ns_is_client(ldlm_res_to_ns(res))) {
2084                 EXIT;
2085                 return;
2086         }
2087
2088 restart:
2089         lock_res(res);
2090         rc = ldlm_reprocess_queue(res, &res->lr_converting, &rpc_list);
2091         if (rc == LDLM_ITER_CONTINUE)
2092                 ldlm_reprocess_queue(res, &res->lr_waiting, &rpc_list);
2093         unlock_res(res);
2094
2095         rc = ldlm_run_ast_work(ldlm_res_to_ns(res), &rpc_list,
2096                                LDLM_WORK_CP_AST);
2097         if (rc == -ERESTART) {
2098                 LASSERT(cfs_list_empty(&rpc_list));
2099                 goto restart;
2100         }
2101 #else
2102         ENTRY;
2103         if (!ns_is_client(ldlm_res_to_ns(res))) {
2104                 CERROR("This is client-side-only module, cannot handle "
2105                        "LDLM_NAMESPACE_SERVER resource type lock.\n");
2106                 LBUG();
2107         }
2108 #endif
2109         EXIT;
2110 }
2111
2112 /**
2113  * Helper function to call blocking AST for LDLM lock \a lock in a
2114  * "cancelling" mode.
2115  */
2116 void ldlm_cancel_callback(struct ldlm_lock *lock)
2117 {
2118         check_res_locked(lock->l_resource);
2119         if (!(lock->l_flags & LDLM_FL_CANCEL)) {
2120                 lock->l_flags |= LDLM_FL_CANCEL;
2121                 if (lock->l_blocking_ast) {
2122                         unlock_res_and_lock(lock);
2123                         lock->l_blocking_ast(lock, NULL, lock->l_ast_data,
2124                                              LDLM_CB_CANCELING);
2125                         lock_res_and_lock(lock);
2126                 } else {
2127                         LDLM_DEBUG(lock, "no blocking ast");
2128                 }
2129         }
2130         lock->l_flags |= LDLM_FL_BL_DONE;
2131 }
2132
2133 /**
2134  * Remove skiplist-enabled LDLM lock \a req from granted list
2135  */
2136 void ldlm_unlink_lock_skiplist(struct ldlm_lock *req)
2137 {
2138         if (req->l_resource->lr_type != LDLM_PLAIN &&
2139             req->l_resource->lr_type != LDLM_IBITS)
2140                 return;
2141
2142         cfs_list_del_init(&req->l_sl_policy);
2143         cfs_list_del_init(&req->l_sl_mode);
2144 }
2145
2146 /**
2147  * Attempts to cancel LDLM lock \a lock that has no reader/writer references.
2148  */
2149 void ldlm_lock_cancel(struct ldlm_lock *lock)
2150 {
2151         struct ldlm_resource *res;
2152         struct ldlm_namespace *ns;
2153         ENTRY;
2154
2155         lock_res_and_lock(lock);
2156
2157         res = lock->l_resource;
2158         ns  = ldlm_res_to_ns(res);
2159
2160         /* Please do not, no matter how tempting, remove this LBUG without
2161          * talking to me first. -phik */
2162         if (lock->l_readers || lock->l_writers) {
2163                 LDLM_ERROR(lock, "lock still has references");
2164                 LBUG();
2165         }
2166
2167         if (lock->l_waited)
2168                 ldlm_del_waiting_lock(lock);
2169
2170         /* Releases cancel callback. */
2171         ldlm_cancel_callback(lock);
2172
2173         /* Yes, second time, just in case it was added again while we were
2174            running with no res lock in ldlm_cancel_callback */
2175         if (lock->l_waited)
2176                 ldlm_del_waiting_lock(lock);
2177
2178         ldlm_resource_unlink_lock(lock);
2179         ldlm_lock_destroy_nolock(lock);
2180
2181         if (lock->l_granted_mode == lock->l_req_mode)
2182                 ldlm_pool_del(&ns->ns_pool, lock);
2183
2184         /* Make sure we will not be called again for same lock what is possible
2185          * if not to zero out lock->l_granted_mode */
2186         lock->l_granted_mode = LCK_MINMODE;
2187         unlock_res_and_lock(lock);
2188
2189         EXIT;
2190 }
2191 EXPORT_SYMBOL(ldlm_lock_cancel);
2192
2193 /**
2194  * Set opaque data into the lock that only makes sense to upper layer.
2195  */
2196 int ldlm_lock_set_data(struct lustre_handle *lockh, void *data)
2197 {
2198         struct ldlm_lock *lock = ldlm_handle2lock(lockh);
2199         int rc = -EINVAL;
2200         ENTRY;
2201
2202         if (lock) {
2203                 if (lock->l_ast_data == NULL)
2204                         lock->l_ast_data = data;
2205                 if (lock->l_ast_data == data)
2206                         rc = 0;
2207                 LDLM_LOCK_PUT(lock);
2208         }
2209         RETURN(rc);
2210 }
2211 EXPORT_SYMBOL(ldlm_lock_set_data);
2212
2213 struct export_cl_data {
2214         struct obd_export       *ecl_exp;
2215         int                     ecl_loop;
2216 };
2217
2218 /**
2219  * Iterator function for ldlm_cancel_locks_for_export.
2220  * Cancels passed locks.
2221  */
2222 int ldlm_cancel_locks_for_export_cb(cfs_hash_t *hs, cfs_hash_bd_t *bd,
2223                                     cfs_hlist_node_t *hnode, void *data)
2224
2225 {
2226         struct export_cl_data   *ecl = (struct export_cl_data *)data;
2227         struct obd_export       *exp  = ecl->ecl_exp;
2228         struct ldlm_lock     *lock = cfs_hash_object(hs, hnode);
2229         struct ldlm_resource *res;
2230
2231         res = ldlm_resource_getref(lock->l_resource);
2232         LDLM_LOCK_GET(lock);
2233
2234         LDLM_DEBUG(lock, "export %p", exp);
2235         ldlm_res_lvbo_update(res, NULL, 1);
2236         ldlm_lock_cancel(lock);
2237         ldlm_reprocess_all(res);
2238         ldlm_resource_putref(res);
2239         LDLM_LOCK_RELEASE(lock);
2240
2241         ecl->ecl_loop++;
2242         if ((ecl->ecl_loop & -ecl->ecl_loop) == ecl->ecl_loop) {
2243                 CDEBUG(D_INFO,
2244                        "Cancel lock %p for export %p (loop %d), still have "
2245                        "%d locks left on hash table.\n",
2246                        lock, exp, ecl->ecl_loop,
2247                        cfs_atomic_read(&hs->hs_count));
2248         }
2249
2250         return 0;
2251 }
2252
2253 /**
2254  * Cancel all locks for given export.
2255  *
2256  * Typically called on client disconnection/eviction
2257  */
2258 void ldlm_cancel_locks_for_export(struct obd_export *exp)
2259 {
2260         struct export_cl_data   ecl = {
2261                 .ecl_exp        = exp,
2262                 .ecl_loop       = 0,
2263         };
2264
2265         cfs_hash_for_each_empty(exp->exp_lock_hash,
2266                                 ldlm_cancel_locks_for_export_cb, &ecl);
2267 }
2268
2269 /**
2270  * Downgrade an exclusive lock.
2271  *
2272  * A fast variant of ldlm_lock_convert for convertion of exclusive
2273  * locks. The convertion is always successful.
2274  * Used by Commit on Sharing (COS) code.
2275  *
2276  * \param lock A lock to convert
2277  * \param new_mode new lock mode
2278  */
2279 void ldlm_lock_downgrade(struct ldlm_lock *lock, int new_mode)
2280 {
2281         ENTRY;
2282
2283         LASSERT(lock->l_granted_mode & (LCK_PW | LCK_EX));
2284         LASSERT(new_mode == LCK_COS);
2285
2286         lock_res_and_lock(lock);
2287         ldlm_resource_unlink_lock(lock);
2288         /*
2289          * Remove the lock from pool as it will be added again in
2290          * ldlm_grant_lock() called below.
2291          */
2292         ldlm_pool_del(&ldlm_lock_to_ns(lock)->ns_pool, lock);
2293
2294         lock->l_req_mode = new_mode;
2295         ldlm_grant_lock(lock, NULL);
2296         unlock_res_and_lock(lock);
2297         ldlm_reprocess_all(lock->l_resource);
2298
2299         EXIT;
2300 }
2301 EXPORT_SYMBOL(ldlm_lock_downgrade);
2302
2303 /**
2304  * Attempt to convert already granted lock to a different mode.
2305  *
2306  * While lock conversion is not currently used, future client-side
2307  * optimizations could take advantage of it to avoid discarding cached
2308  * pages on a file.
2309  */
2310 struct ldlm_resource *ldlm_lock_convert(struct ldlm_lock *lock, int new_mode,
2311                                         __u32 *flags)
2312 {
2313         CFS_LIST_HEAD(rpc_list);
2314         struct ldlm_resource *res;
2315         struct ldlm_namespace *ns;
2316         int granted = 0;
2317 #ifdef HAVE_SERVER_SUPPORT
2318         int old_mode;
2319         struct sl_insert_point prev;
2320 #endif
2321         struct ldlm_interval *node;
2322         ENTRY;
2323
2324         /* Just return if mode is unchanged. */
2325         if (new_mode == lock->l_granted_mode) {
2326                 *flags |= LDLM_FL_BLOCK_GRANTED;
2327                 RETURN(lock->l_resource);
2328         }
2329
2330         /* I can't check the type of lock here because the bitlock of lock
2331          * is not held here, so do the allocation blindly. -jay */
2332         OBD_SLAB_ALLOC_PTR_GFP(node, ldlm_interval_slab, CFS_ALLOC_IO);
2333         if (node == NULL)  /* Actually, this causes EDEADLOCK to be returned */
2334                 RETURN(NULL);
2335
2336         LASSERTF((new_mode == LCK_PW && lock->l_granted_mode == LCK_PR),
2337                  "new_mode %u, granted %u\n", new_mode, lock->l_granted_mode);
2338
2339         lock_res_and_lock(lock);
2340
2341         res = lock->l_resource;
2342         ns  = ldlm_res_to_ns(res);
2343
2344 #ifdef HAVE_SERVER_SUPPORT
2345         old_mode = lock->l_req_mode;
2346 #endif
2347         lock->l_req_mode = new_mode;
2348         if (res->lr_type == LDLM_PLAIN || res->lr_type == LDLM_IBITS) {
2349 #ifdef HAVE_SERVER_SUPPORT
2350                 /* remember the lock position where the lock might be
2351                  * added back to the granted list later and also
2352                  * remember the join mode for skiplist fixing. */
2353                 prev.res_link = lock->l_res_link.prev;
2354                 prev.mode_link = lock->l_sl_mode.prev;
2355                 prev.policy_link = lock->l_sl_policy.prev;
2356 #endif
2357                 ldlm_resource_unlink_lock(lock);
2358         } else {
2359                 ldlm_resource_unlink_lock(lock);
2360                 if (res->lr_type == LDLM_EXTENT) {
2361                         /* FIXME: ugly code, I have to attach the lock to a
2362                          * interval node again since perhaps it will be granted
2363                          * soon */
2364                         CFS_INIT_LIST_HEAD(&node->li_group);
2365                         ldlm_interval_attach(node, lock);
2366                         node = NULL;
2367                 }
2368         }
2369
2370         /*
2371          * Remove old lock from the pool before adding the lock with new
2372          * mode below in ->policy()
2373          */
2374         ldlm_pool_del(&ns->ns_pool, lock);
2375
2376         /* If this is a local resource, put it on the appropriate list. */
2377         if (ns_is_client(ldlm_res_to_ns(res))) {
2378                 if (*flags & (LDLM_FL_BLOCK_CONV | LDLM_FL_BLOCK_GRANTED)) {
2379                         ldlm_resource_add_lock(res, &res->lr_converting, lock);
2380                 } else {
2381                         /* This should never happen, because of the way the
2382                          * server handles conversions. */
2383                         LDLM_ERROR(lock, "Erroneous flags %x on local lock\n",
2384                                    *flags);
2385                         LBUG();
2386
2387                         ldlm_grant_lock(lock, &rpc_list);
2388                         granted = 1;
2389                         /* FIXME: completion handling not with lr_lock held ! */
2390                         if (lock->l_completion_ast)
2391                                 lock->l_completion_ast(lock, 0, NULL);
2392                 }
2393 #ifdef HAVE_SERVER_SUPPORT
2394         } else {
2395                 int rc;
2396                 ldlm_error_t err;
2397                 __u64 pflags = 0;
2398                 ldlm_processing_policy policy;
2399                 policy = ldlm_processing_policy_table[res->lr_type];
2400                 rc = policy(lock, &pflags, 0, &err, &rpc_list);
2401                 if (rc == LDLM_ITER_STOP) {
2402                         lock->l_req_mode = old_mode;
2403                         if (res->lr_type == LDLM_EXTENT)
2404                                 ldlm_extent_add_lock(res, lock);
2405                         else
2406                                 ldlm_granted_list_add_lock(lock, &prev);
2407
2408                         res = NULL;
2409                 } else {
2410                         *flags |= LDLM_FL_BLOCK_GRANTED;
2411                         granted = 1;
2412                 }
2413         }
2414 #else
2415         } else {
2416                 CERROR("This is client-side-only module, cannot handle "
2417                        "LDLM_NAMESPACE_SERVER resource type lock.\n");
2418                 LBUG();
2419         }
2420 #endif
2421         unlock_res_and_lock(lock);
2422
2423         if (granted)
2424                 ldlm_run_ast_work(ns, &rpc_list, LDLM_WORK_CP_AST);
2425         if (node)
2426                 OBD_SLAB_FREE(node, ldlm_interval_slab, sizeof(*node));
2427         RETURN(res);
2428 }
2429 EXPORT_SYMBOL(ldlm_lock_convert);
2430
2431 /**
2432  * Print lock with lock handle \a lockh description into debug log.
2433  *
2434  * Used when printing all locks on a resource for debug purposes.
2435  */
2436 void ldlm_lock_dump_handle(int level, struct lustre_handle *lockh)
2437 {
2438         struct ldlm_lock *lock;
2439
2440         if (!((libcfs_debug | D_ERROR) & level))
2441                 return;
2442
2443         lock = ldlm_handle2lock(lockh);
2444         if (lock == NULL)
2445                 return;
2446
2447         LDLM_DEBUG_LIMIT(level, lock, "###");
2448
2449         LDLM_LOCK_PUT(lock);
2450 }
2451 EXPORT_SYMBOL(ldlm_lock_dump_handle);
2452
2453 /**
2454  * Print lock information with custom message into debug log.
2455  * Helper function.
2456  */
2457 void _ldlm_lock_debug(struct ldlm_lock *lock,
2458                       struct libcfs_debug_msg_data *msgdata,
2459                       const char *fmt, ...)
2460 {
2461         va_list args;
2462         struct obd_export *exp = lock->l_export;
2463         struct ldlm_resource *resource = lock->l_resource;
2464         char *nid = "local";
2465
2466         va_start(args, fmt);
2467
2468         if (exp && exp->exp_connection) {
2469                 nid = libcfs_nid2str(exp->exp_connection->c_peer.nid);
2470         } else if (exp && exp->exp_obd != NULL) {
2471                 struct obd_import *imp = exp->exp_obd->u.cli.cl_import;
2472                 nid = libcfs_nid2str(imp->imp_connection->c_peer.nid);
2473         }
2474
2475         if (resource == NULL) {
2476                 libcfs_debug_vmsg2(msgdata, fmt, args,
2477                        " ns: \?\? lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
2478                        "res: \?\? rrc=\?\? type: \?\?\? flags: "LPX64" nid: %s "
2479                        "remote: "LPX64" expref: %d pid: %u timeout: %lu "
2480                        "lvb_type: %d\n",
2481                        lock,
2482                        lock->l_handle.h_cookie, cfs_atomic_read(&lock->l_refc),
2483                        lock->l_readers, lock->l_writers,
2484                        ldlm_lockname[lock->l_granted_mode],
2485                        ldlm_lockname[lock->l_req_mode],
2486                        lock->l_flags, nid, lock->l_remote_handle.cookie,
2487                        exp ? cfs_atomic_read(&exp->exp_refcount) : -99,
2488                        lock->l_pid, lock->l_callback_timeout, lock->l_lvb_type);
2489                 va_end(args);
2490                 return;
2491         }
2492
2493         switch (resource->lr_type) {
2494         case LDLM_EXTENT:
2495                 libcfs_debug_vmsg2(msgdata, fmt, args,
2496                        " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
2497                        "res: "LPU64"/"LPU64" rrc: %d type: %s ["LPU64"->"LPU64
2498                        "] (req "LPU64"->"LPU64") flags: "LPX64" nid: %s remote:"
2499                        " "LPX64" expref: %d pid: %u timeout: %lu lvb_type: %d\n",
2500                        ldlm_lock_to_ns_name(lock), lock,
2501                        lock->l_handle.h_cookie, cfs_atomic_read(&lock->l_refc),
2502                        lock->l_readers, lock->l_writers,
2503                        ldlm_lockname[lock->l_granted_mode],
2504                        ldlm_lockname[lock->l_req_mode],
2505                        resource->lr_name.name[0],
2506                        resource->lr_name.name[1],
2507                        cfs_atomic_read(&resource->lr_refcount),
2508                        ldlm_typename[resource->lr_type],
2509                        lock->l_policy_data.l_extent.start,
2510                        lock->l_policy_data.l_extent.end,
2511                        lock->l_req_extent.start, lock->l_req_extent.end,
2512                        lock->l_flags, nid, lock->l_remote_handle.cookie,
2513                        exp ? cfs_atomic_read(&exp->exp_refcount) : -99,
2514                        lock->l_pid, lock->l_callback_timeout, lock->l_lvb_type);
2515                 break;
2516
2517         case LDLM_FLOCK:
2518                 libcfs_debug_vmsg2(msgdata, fmt, args,
2519                        " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
2520                        "res: "LPU64"/"LPU64" rrc: %d type: %s pid: %d "
2521                        "["LPU64"->"LPU64"] flags: "LPX64" nid: %s remote: "LPX64
2522                        " expref: %d pid: %u timeout: %lu\n",
2523                        ldlm_lock_to_ns_name(lock), lock,
2524                        lock->l_handle.h_cookie, cfs_atomic_read(&lock->l_refc),
2525                        lock->l_readers, lock->l_writers,
2526                        ldlm_lockname[lock->l_granted_mode],
2527                        ldlm_lockname[lock->l_req_mode],
2528                        resource->lr_name.name[0],
2529                        resource->lr_name.name[1],
2530                        cfs_atomic_read(&resource->lr_refcount),
2531                        ldlm_typename[resource->lr_type],
2532                        lock->l_policy_data.l_flock.pid,
2533                        lock->l_policy_data.l_flock.start,
2534                        lock->l_policy_data.l_flock.end,
2535                        lock->l_flags, nid, lock->l_remote_handle.cookie,
2536                        exp ? cfs_atomic_read(&exp->exp_refcount) : -99,
2537                        lock->l_pid, lock->l_callback_timeout);
2538                 break;
2539
2540         case LDLM_IBITS:
2541                 libcfs_debug_vmsg2(msgdata, fmt, args,
2542                        " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
2543                        "res: "LPU64"/"LPU64" bits "LPX64" rrc: %d type: %s "
2544                        "flags: "LPX64" nid: %s remote: "LPX64" expref: %d "
2545                        "pid: %u timeout: %lu lvb_type: %d\n",
2546                        ldlm_lock_to_ns_name(lock),
2547                        lock, lock->l_handle.h_cookie,
2548                        cfs_atomic_read (&lock->l_refc),
2549                        lock->l_readers, lock->l_writers,
2550                        ldlm_lockname[lock->l_granted_mode],
2551                        ldlm_lockname[lock->l_req_mode],
2552                        resource->lr_name.name[0],
2553                        resource->lr_name.name[1],
2554                        lock->l_policy_data.l_inodebits.bits,
2555                        cfs_atomic_read(&resource->lr_refcount),
2556                        ldlm_typename[resource->lr_type],
2557                        lock->l_flags, nid, lock->l_remote_handle.cookie,
2558                        exp ? cfs_atomic_read(&exp->exp_refcount) : -99,
2559                        lock->l_pid, lock->l_callback_timeout, lock->l_lvb_type);
2560                 break;
2561
2562         default:
2563                 libcfs_debug_vmsg2(msgdata, fmt, args,
2564                        " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
2565                        "res: "LPU64"/"LPU64" rrc: %d type: %s flags: "LPX64" "
2566                        "nid: %s remote: "LPX64" expref: %d pid: %u timeout: %lu"
2567                        "lvb_type: %d\n",
2568                        ldlm_lock_to_ns_name(lock),
2569                        lock, lock->l_handle.h_cookie,
2570                        cfs_atomic_read (&lock->l_refc),
2571                        lock->l_readers, lock->l_writers,
2572                        ldlm_lockname[lock->l_granted_mode],
2573                        ldlm_lockname[lock->l_req_mode],
2574                        resource->lr_name.name[0],
2575                        resource->lr_name.name[1],
2576                        cfs_atomic_read(&resource->lr_refcount),
2577                        ldlm_typename[resource->lr_type],
2578                        lock->l_flags, nid, lock->l_remote_handle.cookie,
2579                        exp ? cfs_atomic_read(&exp->exp_refcount) : -99,
2580                        lock->l_pid, lock->l_callback_timeout, lock->l_lvb_type);
2581                 break;
2582         }
2583         va_end(args);
2584 }
2585 EXPORT_SYMBOL(_ldlm_lock_debug);