Whamcloud - gitweb
LU-2835 ptlrpc: Fix race during exp_flock_hash creation
[fs/lustre-release.git] / lustre / ldlm / ldlm_resource.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_resource.c
37  *
38  * Author: Phil Schwan <phil@clusterfs.com>
39  * Author: Peter Braam <braam@clusterfs.com>
40  */
41
42 #define DEBUG_SUBSYSTEM S_LDLM
43 #ifdef __KERNEL__
44 # include <lustre_dlm.h>
45 #else
46 # include <liblustre.h>
47 #endif
48
49 #include <lustre_fid.h>
50 #include <obd_class.h>
51 #include "ldlm_internal.h"
52
53 struct kmem_cache *ldlm_resource_slab, *ldlm_lock_slab;
54
55 int ldlm_srv_namespace_nr = 0;
56 int ldlm_cli_namespace_nr = 0;
57
58 struct mutex ldlm_srv_namespace_lock;
59 CFS_LIST_HEAD(ldlm_srv_namespace_list);
60
61 struct mutex ldlm_cli_namespace_lock;
62 /* Client Namespaces that have active resources in them.
63  * Once all resources go away, ldlm_poold moves such namespaces to the
64  * inactive list */
65 CFS_LIST_HEAD(ldlm_cli_active_namespace_list);
66 /* Client namespaces that don't have any locks in them */
67 CFS_LIST_HEAD(ldlm_cli_inactive_namespace_list);
68
69 cfs_proc_dir_entry_t *ldlm_type_proc_dir = NULL;
70 cfs_proc_dir_entry_t *ldlm_ns_proc_dir = NULL;
71 cfs_proc_dir_entry_t *ldlm_svc_proc_dir = NULL;
72
73 extern unsigned int ldlm_cancel_unused_locks_before_replay;
74
75 /* during debug dump certain amount of granted locks for one resource to avoid
76  * DDOS. */
77 unsigned int ldlm_dump_granted_max = 256;
78
79 #ifdef LPROCFS
80 static int ldlm_proc_dump_ns(struct file *file, const char *buffer,
81                              unsigned long count, void *data)
82 {
83         ldlm_dump_all_namespaces(LDLM_NAMESPACE_SERVER, D_DLMTRACE);
84         ldlm_dump_all_namespaces(LDLM_NAMESPACE_CLIENT, D_DLMTRACE);
85         RETURN(count);
86 }
87
88 int ldlm_proc_setup(void)
89 {
90         int rc;
91         struct lprocfs_vars list[] = {
92                 { "dump_namespaces", NULL, ldlm_proc_dump_ns, NULL },
93                 { "dump_granted_max",
94                   lprocfs_rd_uint, lprocfs_wr_uint,
95                   &ldlm_dump_granted_max, NULL },
96                 { "cancel_unused_locks_before_replay",
97                   lprocfs_rd_uint, lprocfs_wr_uint,
98                   &ldlm_cancel_unused_locks_before_replay, NULL },
99                 { NULL }};
100         ENTRY;
101         LASSERT(ldlm_ns_proc_dir == NULL);
102
103         ldlm_type_proc_dir = lprocfs_register(OBD_LDLM_DEVICENAME,
104                                               proc_lustre_root,
105                                               NULL, NULL);
106         if (IS_ERR(ldlm_type_proc_dir)) {
107                 CERROR("LProcFS failed in ldlm-init\n");
108                 rc = PTR_ERR(ldlm_type_proc_dir);
109                 GOTO(err, rc);
110         }
111
112         ldlm_ns_proc_dir = lprocfs_register("namespaces",
113                                             ldlm_type_proc_dir,
114                                             NULL, NULL);
115         if (IS_ERR(ldlm_ns_proc_dir)) {
116                 CERROR("LProcFS failed in ldlm-init\n");
117                 rc = PTR_ERR(ldlm_ns_proc_dir);
118                 GOTO(err_type, rc);
119         }
120
121         ldlm_svc_proc_dir = lprocfs_register("services",
122                                             ldlm_type_proc_dir,
123                                             NULL, NULL);
124         if (IS_ERR(ldlm_svc_proc_dir)) {
125                 CERROR("LProcFS failed in ldlm-init\n");
126                 rc = PTR_ERR(ldlm_svc_proc_dir);
127                 GOTO(err_ns, rc);
128         }
129
130         rc = lprocfs_add_vars(ldlm_type_proc_dir, list, NULL);
131
132         RETURN(0);
133
134 err_ns:
135         lprocfs_remove(&ldlm_ns_proc_dir);
136 err_type:
137         lprocfs_remove(&ldlm_type_proc_dir);
138 err:
139         ldlm_svc_proc_dir = NULL;
140         RETURN(rc);
141 }
142
143 void ldlm_proc_cleanup(void)
144 {
145         if (ldlm_svc_proc_dir)
146                 lprocfs_remove(&ldlm_svc_proc_dir);
147
148         if (ldlm_ns_proc_dir)
149                 lprocfs_remove(&ldlm_ns_proc_dir);
150
151         if (ldlm_type_proc_dir)
152                 lprocfs_remove(&ldlm_type_proc_dir);
153 }
154
155 static int lprocfs_rd_ns_resources(char *page, char **start, off_t off,
156                                    int count, int *eof, void *data)
157 {
158         struct ldlm_namespace *ns  = data;
159         __u64                  res = 0;
160         cfs_hash_bd_t          bd;
161         int                    i;
162
163         /* result is not strictly consistant */
164         cfs_hash_for_each_bucket(ns->ns_rs_hash, &bd, i)
165                 res += cfs_hash_bd_count_get(&bd);
166         return lprocfs_rd_u64(page, start, off, count, eof, &res);
167 }
168
169 static int lprocfs_rd_ns_locks(char *page, char **start, off_t off,
170                                int count, int *eof, void *data)
171 {
172         struct ldlm_namespace *ns = data;
173         __u64                  locks;
174
175         locks = lprocfs_stats_collector(ns->ns_stats, LDLM_NSS_LOCKS,
176                                         LPROCFS_FIELDS_FLAGS_SUM);
177         return lprocfs_rd_u64(page, start, off, count, eof, &locks);
178 }
179
180 static int lprocfs_rd_lru_size(char *page, char **start, off_t off,
181                                int count, int *eof, void *data)
182 {
183         struct ldlm_namespace *ns = data;
184         __u32 *nr = &ns->ns_max_unused;
185
186         if (ns_connect_lru_resize(ns))
187                 nr = &ns->ns_nr_unused;
188         return lprocfs_rd_uint(page, start, off, count, eof, nr);
189 }
190
191 static int lprocfs_wr_lru_size(struct file *file, const char *buffer,
192                                unsigned long count, void *data)
193 {
194         struct ldlm_namespace *ns = data;
195         char dummy[MAX_STRING_SIZE + 1], *end;
196         unsigned long tmp;
197         int lru_resize;
198
199         dummy[MAX_STRING_SIZE] = '\0';
200         if (copy_from_user(dummy, buffer, MAX_STRING_SIZE))
201                 return -EFAULT;
202
203         if (strncmp(dummy, "clear", 5) == 0) {
204                 CDEBUG(D_DLMTRACE,
205                        "dropping all unused locks from namespace %s\n",
206                        ldlm_ns_name(ns));
207                 if (ns_connect_lru_resize(ns)) {
208                         int canceled, unused  = ns->ns_nr_unused;
209
210                         /* Try to cancel all @ns_nr_unused locks. */
211                         canceled = ldlm_cancel_lru(ns, unused, 0,
212                                                    LDLM_CANCEL_PASSED);
213                         if (canceled < unused) {
214                                 CDEBUG(D_DLMTRACE,
215                                        "not all requested locks are canceled, "
216                                        "requested: %d, canceled: %d\n", unused,
217                                        canceled);
218                                 return -EINVAL;
219                         }
220                 } else {
221                         tmp = ns->ns_max_unused;
222                         ns->ns_max_unused = 0;
223                         ldlm_cancel_lru(ns, 0, 0, LDLM_CANCEL_PASSED);
224                         ns->ns_max_unused = tmp;
225                 }
226                 return count;
227         }
228
229         tmp = simple_strtoul(dummy, &end, 0);
230         if (dummy == end) {
231                 CERROR("invalid value written\n");
232                 return -EINVAL;
233         }
234         lru_resize = (tmp == 0);
235
236         if (ns_connect_lru_resize(ns)) {
237                 if (!lru_resize)
238                         ns->ns_max_unused = (unsigned int)tmp;
239
240                 if (tmp > ns->ns_nr_unused)
241                         tmp = ns->ns_nr_unused;
242                 tmp = ns->ns_nr_unused - tmp;
243
244                 CDEBUG(D_DLMTRACE,
245                        "changing namespace %s unused locks from %u to %u\n",
246                        ldlm_ns_name(ns), ns->ns_nr_unused,
247                        (unsigned int)tmp);
248                 ldlm_cancel_lru(ns, tmp, LCF_ASYNC, LDLM_CANCEL_PASSED);
249
250                 if (!lru_resize) {
251                         CDEBUG(D_DLMTRACE,
252                                "disable lru_resize for namespace %s\n",
253                                ldlm_ns_name(ns));
254                         ns->ns_connect_flags &= ~OBD_CONNECT_LRU_RESIZE;
255                 }
256         } else {
257                 CDEBUG(D_DLMTRACE,
258                        "changing namespace %s max_unused from %u to %u\n",
259                        ldlm_ns_name(ns), ns->ns_max_unused,
260                        (unsigned int)tmp);
261                 ns->ns_max_unused = (unsigned int)tmp;
262                 ldlm_cancel_lru(ns, 0, LCF_ASYNC, LDLM_CANCEL_PASSED);
263
264                 /* Make sure that LRU resize was originally supported before
265                  * turning it on here. */
266                 if (lru_resize &&
267                     (ns->ns_orig_connect_flags & OBD_CONNECT_LRU_RESIZE)) {
268                         CDEBUG(D_DLMTRACE,
269                                "enable lru_resize for namespace %s\n",
270                                ldlm_ns_name(ns));
271                         ns->ns_connect_flags |= OBD_CONNECT_LRU_RESIZE;
272                 }
273         }
274
275         return count;
276 }
277
278 static int lprocfs_rd_elc(char *page, char **start, off_t off,
279                           int count, int *eof, void *data)
280 {
281         struct ldlm_namespace *ns = data;
282         unsigned int supp = ns_connect_cancelset(ns);
283
284         return lprocfs_rd_uint(page, start, off, count, eof, &supp);
285 }
286
287 static int lprocfs_wr_elc(struct file *file, const char *buffer,
288                                unsigned long count, void *data)
289 {
290         struct ldlm_namespace *ns = data;
291         unsigned int supp = -1;
292         int rc;
293
294         rc = lprocfs_wr_uint(file, buffer, count, &supp);
295         if (rc < 0)
296                 return rc;
297
298         if (supp == 0)
299                 ns->ns_connect_flags &= ~OBD_CONNECT_CANCELSET;
300         else if (ns->ns_orig_connect_flags & OBD_CONNECT_CANCELSET)
301                 ns->ns_connect_flags |= OBD_CONNECT_CANCELSET;
302         return count;
303 }
304
305 void ldlm_namespace_proc_unregister(struct ldlm_namespace *ns)
306 {
307         struct proc_dir_entry *dir;
308
309         dir = lprocfs_srch(ldlm_ns_proc_dir, ldlm_ns_name(ns));
310         if (dir == NULL) {
311                 CERROR("dlm namespace %s has no procfs dir?\n",
312                        ldlm_ns_name(ns));
313         } else {
314                 lprocfs_remove(&dir);
315         }
316
317         if (ns->ns_stats != NULL)
318                 lprocfs_free_stats(&ns->ns_stats);
319 }
320
321 int ldlm_namespace_proc_register(struct ldlm_namespace *ns)
322 {
323         struct lprocfs_vars lock_vars[2];
324         char lock_name[MAX_STRING_SIZE + 1];
325
326         LASSERT(ns != NULL);
327         LASSERT(ns->ns_rs_hash != NULL);
328
329         ns->ns_stats = lprocfs_alloc_stats(LDLM_NSS_LAST, 0);
330         if (ns->ns_stats == NULL)
331                 return -ENOMEM;
332
333         lprocfs_counter_init(ns->ns_stats, LDLM_NSS_LOCKS,
334                              LPROCFS_CNTR_AVGMINMAX, "locks", "locks");
335
336         lock_name[MAX_STRING_SIZE] = '\0';
337
338         memset(lock_vars, 0, sizeof(lock_vars));
339         lock_vars[0].name = lock_name;
340
341         snprintf(lock_name, MAX_STRING_SIZE, "%s/resource_count",
342                  ldlm_ns_name(ns));
343         lock_vars[0].data = ns;
344         lock_vars[0].read_fptr = lprocfs_rd_ns_resources;
345         lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
346
347         snprintf(lock_name, MAX_STRING_SIZE, "%s/lock_count",
348                  ldlm_ns_name(ns));
349         lock_vars[0].data = ns;
350         lock_vars[0].read_fptr = lprocfs_rd_ns_locks;
351         lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
352
353         if (ns_is_client(ns)) {
354                 snprintf(lock_name, MAX_STRING_SIZE, "%s/lock_unused_count",
355                          ldlm_ns_name(ns));
356                 lock_vars[0].data = &ns->ns_nr_unused;
357                 lock_vars[0].read_fptr = lprocfs_rd_uint;
358                 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
359
360                 snprintf(lock_name, MAX_STRING_SIZE, "%s/lru_size",
361                          ldlm_ns_name(ns));
362                 lock_vars[0].data = ns;
363                 lock_vars[0].read_fptr = lprocfs_rd_lru_size;
364                 lock_vars[0].write_fptr = lprocfs_wr_lru_size;
365                 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
366
367                 snprintf(lock_name, MAX_STRING_SIZE, "%s/lru_max_age",
368                          ldlm_ns_name(ns));
369                 lock_vars[0].data = &ns->ns_max_age;
370                 lock_vars[0].read_fptr = lprocfs_rd_uint;
371                 lock_vars[0].write_fptr = lprocfs_wr_uint;
372                 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
373
374                 snprintf(lock_name, MAX_STRING_SIZE, "%s/early_lock_cancel",
375                          ldlm_ns_name(ns));
376                 lock_vars[0].data = ns;
377                 lock_vars[0].read_fptr = lprocfs_rd_elc;
378                 lock_vars[0].write_fptr = lprocfs_wr_elc;
379                 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
380         } else {
381                 snprintf(lock_name, MAX_STRING_SIZE, "%s/ctime_age_limit",
382                          ldlm_ns_name(ns));
383                 lock_vars[0].data = &ns->ns_ctime_age_limit;
384                 lock_vars[0].read_fptr = lprocfs_rd_uint;
385                 lock_vars[0].write_fptr = lprocfs_wr_uint;
386                 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
387
388                 snprintf(lock_name, MAX_STRING_SIZE, "%s/lock_timeouts",
389                          ldlm_ns_name(ns));
390                 lock_vars[0].data = &ns->ns_timeouts;
391                 lock_vars[0].read_fptr = lprocfs_rd_uint;
392                 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
393
394                 snprintf(lock_name, MAX_STRING_SIZE, "%s/max_nolock_bytes",
395                          ldlm_ns_name(ns));
396                 lock_vars[0].data = &ns->ns_max_nolock_size;
397                 lock_vars[0].read_fptr = lprocfs_rd_uint;
398                 lock_vars[0].write_fptr = lprocfs_wr_uint;
399                 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
400
401                 snprintf(lock_name, MAX_STRING_SIZE, "%s/contention_seconds",
402                          ldlm_ns_name(ns));
403                 lock_vars[0].data = &ns->ns_contention_time;
404                 lock_vars[0].read_fptr = lprocfs_rd_uint;
405                 lock_vars[0].write_fptr = lprocfs_wr_uint;
406                 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
407
408                 snprintf(lock_name, MAX_STRING_SIZE, "%s/contended_locks",
409                          ldlm_ns_name(ns));
410                 lock_vars[0].data = &ns->ns_contended_locks;
411                 lock_vars[0].read_fptr = lprocfs_rd_uint;
412                 lock_vars[0].write_fptr = lprocfs_wr_uint;
413                 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
414
415                 snprintf(lock_name, MAX_STRING_SIZE, "%s/max_parallel_ast",
416                          ldlm_ns_name(ns));
417                 lock_vars[0].data = &ns->ns_max_parallel_ast;
418                 lock_vars[0].read_fptr = lprocfs_rd_uint;
419                 lock_vars[0].write_fptr = lprocfs_wr_uint;
420                 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
421         }
422         return 0;
423 }
424 #undef MAX_STRING_SIZE
425 #else /* LPROCFS */
426
427 #define ldlm_namespace_proc_unregister(ns)      ({;})
428 #define ldlm_namespace_proc_register(ns)        ({0;})
429
430 #endif /* LPROCFS */
431
432 static unsigned ldlm_res_hop_hash(cfs_hash_t *hs,
433                                   const void *key, unsigned mask)
434 {
435         const struct ldlm_res_id     *id  = key;
436         unsigned                val = 0;
437         unsigned                i;
438
439         for (i = 0; i < RES_NAME_SIZE; i++)
440                 val += id->name[i];
441         return val & mask;
442 }
443
444 static unsigned ldlm_res_hop_fid_hash(cfs_hash_t *hs,
445                                       const void *key, unsigned mask)
446 {
447         const struct ldlm_res_id *id = key;
448         struct lu_fid       fid;
449         __u32               hash;
450         __u32               val;
451
452         fid.f_seq = id->name[LUSTRE_RES_ID_SEQ_OFF];
453         fid.f_oid = (__u32)id->name[LUSTRE_RES_ID_VER_OID_OFF];
454         fid.f_ver = (__u32)(id->name[LUSTRE_RES_ID_VER_OID_OFF] >> 32);
455
456         hash = fid_flatten32(&fid);
457         hash += (hash >> 4) + (hash << 12); /* mixing oid and seq */
458         if (id->name[LUSTRE_RES_ID_HSH_OFF] != 0) {
459                 val = id->name[LUSTRE_RES_ID_HSH_OFF];
460                 hash += (val >> 5) + (val << 11);
461         } else {
462                 val = fid_oid(&fid);
463         }
464         hash = cfs_hash_long(hash, hs->hs_bkt_bits);
465         /* give me another random factor */
466         hash -= cfs_hash_long((unsigned long)hs, val % 11 + 3);
467
468         hash <<= hs->hs_cur_bits - hs->hs_bkt_bits;
469         hash |= ldlm_res_hop_hash(hs, key, CFS_HASH_NBKT(hs) - 1);
470
471         return hash & mask;
472 }
473
474 static void *ldlm_res_hop_key(cfs_hlist_node_t *hnode)
475 {
476         struct ldlm_resource   *res;
477
478         res = cfs_hlist_entry(hnode, struct ldlm_resource, lr_hash);
479         return &res->lr_name;
480 }
481
482 static int ldlm_res_hop_keycmp(const void *key, cfs_hlist_node_t *hnode)
483 {
484         struct ldlm_resource   *res;
485
486         res = cfs_hlist_entry(hnode, struct ldlm_resource, lr_hash);
487         return ldlm_res_eq((const struct ldlm_res_id *)key,
488                            (const struct ldlm_res_id *)&res->lr_name);
489 }
490
491 static void *ldlm_res_hop_object(cfs_hlist_node_t *hnode)
492 {
493         return cfs_hlist_entry(hnode, struct ldlm_resource, lr_hash);
494 }
495
496 static void ldlm_res_hop_get_locked(cfs_hash_t *hs, cfs_hlist_node_t *hnode)
497 {
498         struct ldlm_resource *res;
499
500         res = cfs_hlist_entry(hnode, struct ldlm_resource, lr_hash);
501         ldlm_resource_getref(res);
502 }
503
504 static void ldlm_res_hop_put_locked(cfs_hash_t *hs, cfs_hlist_node_t *hnode)
505 {
506         struct ldlm_resource *res;
507
508         res = cfs_hlist_entry(hnode, struct ldlm_resource, lr_hash);
509         /* cfs_hash_for_each_nolock is the only chance we call it */
510         ldlm_resource_putref_locked(res);
511 }
512
513 static void ldlm_res_hop_put(cfs_hash_t *hs, cfs_hlist_node_t *hnode)
514 {
515         struct ldlm_resource *res;
516
517         res = cfs_hlist_entry(hnode, struct ldlm_resource, lr_hash);
518         ldlm_resource_putref(res);
519 }
520
521 cfs_hash_ops_t ldlm_ns_hash_ops = {
522         .hs_hash        = ldlm_res_hop_hash,
523         .hs_key         = ldlm_res_hop_key,
524         .hs_keycmp      = ldlm_res_hop_keycmp,
525         .hs_keycpy      = NULL,
526         .hs_object      = ldlm_res_hop_object,
527         .hs_get         = ldlm_res_hop_get_locked,
528         .hs_put_locked  = ldlm_res_hop_put_locked,
529         .hs_put         = ldlm_res_hop_put
530 };
531
532 cfs_hash_ops_t ldlm_ns_fid_hash_ops = {
533         .hs_hash        = ldlm_res_hop_fid_hash,
534         .hs_key         = ldlm_res_hop_key,
535         .hs_keycmp      = ldlm_res_hop_keycmp,
536         .hs_keycpy      = NULL,
537         .hs_object      = ldlm_res_hop_object,
538         .hs_get         = ldlm_res_hop_get_locked,
539         .hs_put_locked  = ldlm_res_hop_put_locked,
540         .hs_put         = ldlm_res_hop_put
541 };
542
543 typedef struct {
544         ldlm_ns_type_t  nsd_type;
545         /** hash bucket bits */
546         unsigned        nsd_bkt_bits;
547         /** hash bits */
548         unsigned        nsd_all_bits;
549         /** hash operations */
550         cfs_hash_ops_t *nsd_hops;
551 } ldlm_ns_hash_def_t;
552
553 ldlm_ns_hash_def_t ldlm_ns_hash_defs[] =
554 {
555         {
556                 .nsd_type       = LDLM_NS_TYPE_MDC,
557                 .nsd_bkt_bits   = 11,
558                 .nsd_all_bits   = 16,
559                 .nsd_hops       = &ldlm_ns_fid_hash_ops,
560         },
561         {
562                 .nsd_type       = LDLM_NS_TYPE_MDT,
563                 .nsd_bkt_bits   = 14,
564                 .nsd_all_bits   = 21,
565                 .nsd_hops       = &ldlm_ns_fid_hash_ops,
566         },
567         {
568                 .nsd_type       = LDLM_NS_TYPE_OSC,
569                 .nsd_bkt_bits   = 8,
570                 .nsd_all_bits   = 12,
571                 .nsd_hops       = &ldlm_ns_hash_ops,
572         },
573         {
574                 .nsd_type       = LDLM_NS_TYPE_OST,
575                 .nsd_bkt_bits   = 11,
576                 .nsd_all_bits   = 17,
577                 .nsd_hops       = &ldlm_ns_hash_ops,
578         },
579         {
580                 .nsd_type       = LDLM_NS_TYPE_MGC,
581                 .nsd_bkt_bits   = 4,
582                 .nsd_all_bits   = 4,
583                 .nsd_hops       = &ldlm_ns_hash_ops,
584         },
585         {
586                 .nsd_type       = LDLM_NS_TYPE_MGT,
587                 .nsd_bkt_bits   = 4,
588                 .nsd_all_bits   = 4,
589                 .nsd_hops       = &ldlm_ns_hash_ops,
590         },
591         {
592                 .nsd_type       = LDLM_NS_TYPE_UNKNOWN,
593         },
594 };
595
596 /**
597  * Create and initialize new empty namespace.
598  */
599 struct ldlm_namespace *ldlm_namespace_new(struct obd_device *obd, char *name,
600                                           ldlm_side_t client,
601                                           ldlm_appetite_t apt,
602                                           ldlm_ns_type_t ns_type)
603 {
604         struct ldlm_namespace *ns = NULL;
605         struct ldlm_ns_bucket *nsb;
606         ldlm_ns_hash_def_t    *nsd;
607         cfs_hash_bd_t          bd;
608         int                    idx;
609         int                    rc;
610         ENTRY;
611
612         LASSERT(obd != NULL);
613
614         rc = ldlm_get_ref();
615         if (rc) {
616                 CERROR("ldlm_get_ref failed: %d\n", rc);
617                 RETURN(NULL);
618         }
619
620         for (idx = 0;;idx++) {
621                 nsd = &ldlm_ns_hash_defs[idx];
622                 if (nsd->nsd_type == LDLM_NS_TYPE_UNKNOWN) {
623                         CERROR("Unknown type %d for ns %s\n", ns_type, name);
624                         GOTO(out_ref, NULL);
625                 }
626
627                 if (nsd->nsd_type == ns_type)
628                         break;
629         }
630
631         OBD_ALLOC_PTR(ns);
632         if (!ns)
633                 GOTO(out_ref, NULL);
634
635         ns->ns_rs_hash = cfs_hash_create(name,
636                                          nsd->nsd_all_bits, nsd->nsd_all_bits,
637                                          nsd->nsd_bkt_bits, sizeof(*nsb),
638                                          CFS_HASH_MIN_THETA,
639                                          CFS_HASH_MAX_THETA,
640                                          nsd->nsd_hops,
641                                          CFS_HASH_DEPTH |
642                                          CFS_HASH_BIGNAME |
643                                          CFS_HASH_SPIN_BKTLOCK |
644                                          CFS_HASH_NO_ITEMREF);
645         if (ns->ns_rs_hash == NULL)
646                 GOTO(out_ns, NULL);
647
648         cfs_hash_for_each_bucket(ns->ns_rs_hash, &bd, idx) {
649                 nsb = cfs_hash_bd_extra_get(ns->ns_rs_hash, &bd);
650                 at_init(&nsb->nsb_at_estimate, ldlm_enqueue_min, 0);
651                 nsb->nsb_namespace = ns;
652         }
653
654         ns->ns_obd      = obd;
655         ns->ns_appetite = apt;
656         ns->ns_client   = client;
657
658         CFS_INIT_LIST_HEAD(&ns->ns_list_chain);
659         CFS_INIT_LIST_HEAD(&ns->ns_unused_list);
660         spin_lock_init(&ns->ns_lock);
661         cfs_atomic_set(&ns->ns_bref, 0);
662         cfs_waitq_init(&ns->ns_waitq);
663
664         ns->ns_max_nolock_size    = NS_DEFAULT_MAX_NOLOCK_BYTES;
665         ns->ns_contention_time    = NS_DEFAULT_CONTENTION_SECONDS;
666         ns->ns_contended_locks    = NS_DEFAULT_CONTENDED_LOCKS;
667
668         ns->ns_max_parallel_ast   = LDLM_DEFAULT_PARALLEL_AST_LIMIT;
669         ns->ns_nr_unused          = 0;
670         ns->ns_max_unused         = LDLM_DEFAULT_LRU_SIZE;
671         ns->ns_max_age            = LDLM_DEFAULT_MAX_ALIVE;
672         ns->ns_ctime_age_limit    = LDLM_CTIME_AGE_LIMIT;
673         ns->ns_timeouts           = 0;
674         ns->ns_orig_connect_flags = 0;
675         ns->ns_connect_flags      = 0;
676         ns->ns_stopping           = 0;
677         rc = ldlm_namespace_proc_register(ns);
678         if (rc != 0) {
679                 CERROR("Can't initialize ns proc, rc %d\n", rc);
680                 GOTO(out_hash, rc);
681         }
682
683         idx = ldlm_namespace_nr_read(client);
684         rc = ldlm_pool_init(&ns->ns_pool, ns, idx, client);
685         if (rc) {
686                 CERROR("Can't initialize lock pool, rc %d\n", rc);
687                 GOTO(out_proc, rc);
688         }
689
690         ldlm_namespace_register(ns, client);
691         RETURN(ns);
692 out_proc:
693         ldlm_namespace_proc_unregister(ns);
694         ldlm_namespace_cleanup(ns, 0);
695 out_hash:
696         cfs_hash_putref(ns->ns_rs_hash);
697 out_ns:
698         OBD_FREE_PTR(ns);
699 out_ref:
700         ldlm_put_ref();
701         RETURN(NULL);
702 }
703 EXPORT_SYMBOL(ldlm_namespace_new);
704
705 extern struct ldlm_lock *ldlm_lock_get(struct ldlm_lock *lock);
706
707 /**
708  * Cancel and destroy all locks on a resource.
709  *
710  * If flags contains FL_LOCAL_ONLY, don't try to tell the server, just
711  * clean up.  This is currently only used for recovery, and we make
712  * certain assumptions as a result--notably, that we shouldn't cancel
713  * locks with refs.
714  */
715 static void cleanup_resource(struct ldlm_resource *res, cfs_list_t *q,
716                              __u64 flags)
717 {
718         cfs_list_t *tmp;
719         int rc = 0, client = ns_is_client(ldlm_res_to_ns(res));
720         bool local_only = !!(flags & LDLM_FL_LOCAL_ONLY);
721
722         do {
723                 struct ldlm_lock *lock = NULL;
724
725                 /* First, we look for non-cleaned-yet lock
726                  * all cleaned locks are marked by CLEANED flag. */
727                 lock_res(res);
728                 cfs_list_for_each(tmp, q) {
729                         lock = cfs_list_entry(tmp, struct ldlm_lock,
730                                               l_res_link);
731                         if (lock->l_flags & LDLM_FL_CLEANED) {
732                                 lock = NULL;
733                                 continue;
734                         }
735                         LDLM_LOCK_GET(lock);
736                         lock->l_flags |= LDLM_FL_CLEANED;
737                         break;
738                 }
739
740                 if (lock == NULL) {
741                         unlock_res(res);
742                         break;
743                 }
744
745                 /* Set CBPENDING so nothing in the cancellation path
746                  * can match this lock. */
747                 lock->l_flags |= LDLM_FL_CBPENDING;
748                 lock->l_flags |= LDLM_FL_FAILED;
749                 lock->l_flags |= flags;
750
751                 /* ... without sending a CANCEL message for local_only. */
752                 if (local_only)
753                         lock->l_flags |= LDLM_FL_LOCAL_ONLY;
754
755                 if (local_only && (lock->l_readers || lock->l_writers)) {
756                         /* This is a little bit gross, but much better than the
757                          * alternative: pretend that we got a blocking AST from
758                          * the server, so that when the lock is decref'd, it
759                          * will go away ... */
760                         unlock_res(res);
761                         LDLM_DEBUG(lock, "setting FL_LOCAL_ONLY");
762                         if (lock->l_completion_ast)
763                                 lock->l_completion_ast(lock, 0, NULL);
764                         LDLM_LOCK_RELEASE(lock);
765                         continue;
766                 }
767
768                 if (client) {
769                         struct lustre_handle lockh;
770
771                         unlock_res(res);
772                         ldlm_lock2handle(lock, &lockh);
773                         rc = ldlm_cli_cancel(&lockh, LCF_ASYNC);
774                         if (rc)
775                                 CERROR("ldlm_cli_cancel: %d\n", rc);
776                 } else {
777                         ldlm_resource_unlink_lock(lock);
778                         unlock_res(res);
779                         LDLM_DEBUG(lock, "Freeing a lock still held by a "
780                                    "client node");
781                         ldlm_lock_destroy(lock);
782                 }
783                 LDLM_LOCK_RELEASE(lock);
784         } while (1);
785 }
786
787 static int ldlm_resource_clean(cfs_hash_t *hs, cfs_hash_bd_t *bd,
788                                cfs_hlist_node_t *hnode, void *arg)
789 {
790         struct ldlm_resource *res = cfs_hash_object(hs, hnode);
791         __u64 flags = *(__u64 *)arg;
792
793         cleanup_resource(res, &res->lr_granted, flags);
794         cleanup_resource(res, &res->lr_converting, flags);
795         cleanup_resource(res, &res->lr_waiting, flags);
796
797         return 0;
798 }
799
800 static int ldlm_resource_complain(cfs_hash_t *hs, cfs_hash_bd_t *bd,
801                                   cfs_hlist_node_t *hnode, void *arg)
802 {
803         struct ldlm_resource  *res = cfs_hash_object(hs, hnode);
804
805         lock_res(res);
806         CERROR("%s: namespace resource "DLDLMRES" (%p) refcount nonzero "
807                "(%d) after lock cleanup; forcing cleanup.\n",
808                ldlm_ns_name(ldlm_res_to_ns(res)), PLDLMRES(res), res,
809                cfs_atomic_read(&res->lr_refcount) - 1);
810
811         ldlm_resource_dump(D_ERROR, res);
812         unlock_res(res);
813         return 0;
814 }
815
816 /**
817  * Cancel and destroy all locks in the namespace.
818  *
819  * Typically used during evictions when server notified client that it was
820  * evicted and all of its state needs to be destroyed.
821  * Also used during shutdown.
822  */
823 int ldlm_namespace_cleanup(struct ldlm_namespace *ns, __u64 flags)
824 {
825         if (ns == NULL) {
826                 CDEBUG(D_INFO, "NULL ns, skipping cleanup\n");
827                 return ELDLM_OK;
828         }
829
830         cfs_hash_for_each_nolock(ns->ns_rs_hash, ldlm_resource_clean, &flags);
831         cfs_hash_for_each_nolock(ns->ns_rs_hash, ldlm_resource_complain, NULL);
832         return ELDLM_OK;
833 }
834 EXPORT_SYMBOL(ldlm_namespace_cleanup);
835
836 /**
837  * Attempts to free namespace.
838  *
839  * Only used when namespace goes away, like during an unmount.
840  */
841 static int __ldlm_namespace_free(struct ldlm_namespace *ns, int force)
842 {
843         ENTRY;
844
845         /* At shutdown time, don't call the cancellation callback */
846         ldlm_namespace_cleanup(ns, force ? LDLM_FL_LOCAL_ONLY : 0);
847
848         if (cfs_atomic_read(&ns->ns_bref) > 0) {
849                 struct l_wait_info lwi = LWI_INTR(LWI_ON_SIGNAL_NOOP, NULL);
850                 int rc;
851                 CDEBUG(D_DLMTRACE,
852                        "dlm namespace %s free waiting on refcount %d\n",
853                        ldlm_ns_name(ns), cfs_atomic_read(&ns->ns_bref));
854 force_wait:
855                 if (force)
856                         lwi = LWI_TIMEOUT(obd_timeout * CFS_HZ / 4, NULL, NULL);
857
858                 rc = l_wait_event(ns->ns_waitq,
859                                   cfs_atomic_read(&ns->ns_bref) == 0, &lwi);
860
861                 /* Forced cleanups should be able to reclaim all references,
862                  * so it's safe to wait forever... we can't leak locks... */
863                 if (force && rc == -ETIMEDOUT) {
864                         LCONSOLE_ERROR("Forced cleanup waiting for %s "
865                                        "namespace with %d resources in use, "
866                                        "(rc=%d)\n", ldlm_ns_name(ns),
867                                        cfs_atomic_read(&ns->ns_bref), rc);
868                         GOTO(force_wait, rc);
869                 }
870
871                 if (cfs_atomic_read(&ns->ns_bref)) {
872                         LCONSOLE_ERROR("Cleanup waiting for %s namespace "
873                                        "with %d resources in use, (rc=%d)\n",
874                                        ldlm_ns_name(ns),
875                                        cfs_atomic_read(&ns->ns_bref), rc);
876                         RETURN(ELDLM_NAMESPACE_EXISTS);
877                 }
878                 CDEBUG(D_DLMTRACE, "dlm namespace %s free done waiting\n",
879                        ldlm_ns_name(ns));
880         }
881
882         RETURN(ELDLM_OK);
883 }
884
885 /**
886  * Performs various cleanups for passed \a ns to make it drop refc and be
887  * ready for freeing. Waits for refc == 0.
888  *
889  * The following is done:
890  * (0) Unregister \a ns from its list to make inaccessible for potential
891  * users like pools thread and others;
892  * (1) Clear all locks in \a ns.
893  */
894 void ldlm_namespace_free_prior(struct ldlm_namespace *ns,
895                                struct obd_import *imp,
896                                int force)
897 {
898         int rc;
899         ENTRY;
900         if (!ns) {
901                 EXIT;
902                 return;
903         }
904
905         spin_lock(&ns->ns_lock);
906         ns->ns_stopping = 1;
907         spin_unlock(&ns->ns_lock);
908
909         /*
910          * Can fail with -EINTR when force == 0 in which case try harder.
911          */
912         rc = __ldlm_namespace_free(ns, force);
913         if (rc != ELDLM_OK) {
914                 if (imp) {
915                         ptlrpc_disconnect_import(imp, 0);
916                         ptlrpc_invalidate_import(imp);
917                 }
918
919                 /*
920                  * With all requests dropped and the import inactive
921                  * we are gaurenteed all reference will be dropped.
922                  */
923                 rc = __ldlm_namespace_free(ns, 1);
924                 LASSERT(rc == 0);
925         }
926         EXIT;
927 }
928
929 /**
930  * Performs freeing memory structures related to \a ns. This is only done
931  * when ldlm_namespce_free_prior() successfully removed all resources
932  * referencing \a ns and its refc == 0.
933  */
934 void ldlm_namespace_free_post(struct ldlm_namespace *ns)
935 {
936         ENTRY;
937         if (!ns) {
938                 EXIT;
939                 return;
940         }
941
942         /* Make sure that nobody can find this ns in its list. */
943         ldlm_namespace_unregister(ns, ns->ns_client);
944         /* Fini pool _before_ parent proc dir is removed. This is important as
945          * ldlm_pool_fini() removes own proc dir which is child to @dir.
946          * Removing it after @dir may cause oops. */
947         ldlm_pool_fini(&ns->ns_pool);
948
949         ldlm_namespace_proc_unregister(ns);
950         cfs_hash_putref(ns->ns_rs_hash);
951         /* Namespace \a ns should be not on list at this time, otherwise
952          * this will cause issues related to using freed \a ns in poold
953          * thread. */
954         LASSERT(cfs_list_empty(&ns->ns_list_chain));
955         OBD_FREE_PTR(ns);
956         ldlm_put_ref();
957         EXIT;
958 }
959
960 /**
961  * Cleanup the resource, and free namespace.
962  * bug 12864:
963  * Deadlock issue:
964  * proc1: destroy import
965  *        class_disconnect_export(grab cl_sem) ->
966  *              -> ldlm_namespace_free ->
967  *              -> lprocfs_remove(grab _lprocfs_lock).
968  * proc2: read proc info
969  *        lprocfs_fops_read(grab _lprocfs_lock) ->
970  *              -> osc_rd_active, etc(grab cl_sem).
971  *
972  * So that I have to split the ldlm_namespace_free into two parts - the first
973  * part ldlm_namespace_free_prior is used to cleanup the resource which is
974  * being used; the 2nd part ldlm_namespace_free_post is used to unregister the
975  * lprocfs entries, and then free memory. It will be called w/o cli->cl_sem
976  * held.
977  */
978 void ldlm_namespace_free(struct ldlm_namespace *ns,
979                          struct obd_import *imp,
980                          int force)
981 {
982         ldlm_namespace_free_prior(ns, imp, force);
983         ldlm_namespace_free_post(ns);
984 }
985 EXPORT_SYMBOL(ldlm_namespace_free);
986
987 void ldlm_namespace_get(struct ldlm_namespace *ns)
988 {
989         cfs_atomic_inc(&ns->ns_bref);
990 }
991 EXPORT_SYMBOL(ldlm_namespace_get);
992
993 /* This is only for callers that care about refcount */
994 int ldlm_namespace_get_return(struct ldlm_namespace *ns)
995 {
996         return cfs_atomic_inc_return(&ns->ns_bref);
997 }
998
999 void ldlm_namespace_put(struct ldlm_namespace *ns)
1000 {
1001         if (cfs_atomic_dec_and_lock(&ns->ns_bref, &ns->ns_lock)) {
1002                 cfs_waitq_signal(&ns->ns_waitq);
1003                 spin_unlock(&ns->ns_lock);
1004         }
1005 }
1006 EXPORT_SYMBOL(ldlm_namespace_put);
1007
1008 /** Register \a ns in the list of namespaces */
1009 void ldlm_namespace_register(struct ldlm_namespace *ns, ldlm_side_t client)
1010 {
1011         mutex_lock(ldlm_namespace_lock(client));
1012         LASSERT(cfs_list_empty(&ns->ns_list_chain));
1013         cfs_list_add(&ns->ns_list_chain, ldlm_namespace_inactive_list(client));
1014         ldlm_namespace_nr_inc(client);
1015         mutex_unlock(ldlm_namespace_lock(client));
1016 }
1017
1018 /** Unregister \a ns from the list of namespaces. */
1019 void ldlm_namespace_unregister(struct ldlm_namespace *ns, ldlm_side_t client)
1020 {
1021         mutex_lock(ldlm_namespace_lock(client));
1022         LASSERT(!cfs_list_empty(&ns->ns_list_chain));
1023         /* Some asserts and possibly other parts of the code are still
1024          * using list_empty(&ns->ns_list_chain). This is why it is
1025          * important to use list_del_init() here. */
1026         cfs_list_del_init(&ns->ns_list_chain);
1027         ldlm_namespace_nr_dec(client);
1028         mutex_unlock(ldlm_namespace_lock(client));
1029 }
1030
1031 /** Should be called with ldlm_namespace_lock(client) taken. */
1032 void ldlm_namespace_move_to_active_locked(struct ldlm_namespace *ns,
1033                                        ldlm_side_t client)
1034 {
1035         LASSERT(!cfs_list_empty(&ns->ns_list_chain));
1036         LASSERT_MUTEX_LOCKED(ldlm_namespace_lock(client));
1037         cfs_list_move_tail(&ns->ns_list_chain, ldlm_namespace_list(client));
1038 }
1039
1040 /** Should be called with ldlm_namespace_lock(client) taken. */
1041 void ldlm_namespace_move_to_inactive_locked(struct ldlm_namespace *ns,
1042                                          ldlm_side_t client)
1043 {
1044         LASSERT(!cfs_list_empty(&ns->ns_list_chain));
1045         LASSERT_MUTEX_LOCKED(ldlm_namespace_lock(client));
1046         cfs_list_move_tail(&ns->ns_list_chain,
1047                            ldlm_namespace_inactive_list(client));
1048 }
1049
1050 /** Should be called with ldlm_namespace_lock(client) taken. */
1051 struct ldlm_namespace *ldlm_namespace_first_locked(ldlm_side_t client)
1052 {
1053         LASSERT_MUTEX_LOCKED(ldlm_namespace_lock(client));
1054         LASSERT(!cfs_list_empty(ldlm_namespace_list(client)));
1055         return container_of(ldlm_namespace_list(client)->next,
1056                 struct ldlm_namespace, ns_list_chain);
1057 }
1058
1059 /** Create and initialize new resource. */
1060 static struct ldlm_resource *ldlm_resource_new(void)
1061 {
1062         struct ldlm_resource *res;
1063         int idx;
1064
1065         OBD_SLAB_ALLOC_PTR_GFP(res, ldlm_resource_slab, __GFP_IO);
1066         if (res == NULL)
1067                 return NULL;
1068
1069         CFS_INIT_LIST_HEAD(&res->lr_granted);
1070         CFS_INIT_LIST_HEAD(&res->lr_converting);
1071         CFS_INIT_LIST_HEAD(&res->lr_waiting);
1072
1073         /* Initialize interval trees for each lock mode. */
1074         for (idx = 0; idx < LCK_MODE_NUM; idx++) {
1075                 res->lr_itree[idx].lit_size = 0;
1076                 res->lr_itree[idx].lit_mode = 1 << idx;
1077                 res->lr_itree[idx].lit_root = NULL;
1078         }
1079
1080         cfs_atomic_set(&res->lr_refcount, 1);
1081         spin_lock_init(&res->lr_lock);
1082         lu_ref_init(&res->lr_reference);
1083
1084         /* The creator of the resource must unlock the mutex after LVB
1085          * initialization. */
1086         mutex_init(&res->lr_lvb_mutex);
1087         mutex_lock(&res->lr_lvb_mutex);
1088
1089         return res;
1090 }
1091
1092 /**
1093  * Return a reference to resource with given name, creating it if necessary.
1094  * Args: namespace with ns_lock unlocked
1095  * Locks: takes and releases NS hash-lock and res->lr_lock
1096  * Returns: referenced, unlocked ldlm_resource or NULL
1097  */
1098 struct ldlm_resource *
1099 ldlm_resource_get(struct ldlm_namespace *ns, struct ldlm_resource *parent,
1100                   const struct ldlm_res_id *name, ldlm_type_t type, int create)
1101 {
1102         cfs_hlist_node_t     *hnode;
1103         struct ldlm_resource *res;
1104         cfs_hash_bd_t         bd;
1105         __u64                 version;
1106         int                   ns_refcount = 0;
1107
1108         LASSERT(ns != NULL);
1109         LASSERT(parent == NULL);
1110         LASSERT(ns->ns_rs_hash != NULL);
1111         LASSERT(name->name[0] != 0);
1112
1113         cfs_hash_bd_get_and_lock(ns->ns_rs_hash, (void *)name, &bd, 0);
1114         hnode = cfs_hash_bd_lookup_locked(ns->ns_rs_hash, &bd, (void *)name);
1115         if (hnode != NULL) {
1116                 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 0);
1117                 res = cfs_hlist_entry(hnode, struct ldlm_resource, lr_hash);
1118                 /* Synchronize with regard to resource creation. */
1119                 if (ns->ns_lvbo && ns->ns_lvbo->lvbo_init) {
1120                         mutex_lock(&res->lr_lvb_mutex);
1121                         mutex_unlock(&res->lr_lvb_mutex);
1122                 }
1123
1124                 if (unlikely(res->lr_lvb_len < 0)) {
1125                         ldlm_resource_putref(res);
1126                         res = NULL;
1127                 }
1128                 return res;
1129         }
1130
1131         version = cfs_hash_bd_version_get(&bd);
1132         cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 0);
1133
1134         if (create == 0)
1135                 return NULL;
1136
1137         LASSERTF(type >= LDLM_MIN_TYPE && type < LDLM_MAX_TYPE,
1138                  "type: %d\n", type);
1139         res = ldlm_resource_new();
1140         if (!res)
1141                 return NULL;
1142
1143         res->lr_ns_bucket  = cfs_hash_bd_extra_get(ns->ns_rs_hash, &bd);
1144         res->lr_name       = *name;
1145         res->lr_type       = type;
1146         res->lr_most_restr = LCK_NL;
1147
1148         cfs_hash_bd_lock(ns->ns_rs_hash, &bd, 1);
1149         hnode = (version == cfs_hash_bd_version_get(&bd)) ?  NULL :
1150                 cfs_hash_bd_lookup_locked(ns->ns_rs_hash, &bd, (void *)name);
1151
1152         if (hnode != NULL) {
1153                 /* Someone won the race and already added the resource. */
1154                 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1155                 /* Clean lu_ref for failed resource. */
1156                 lu_ref_fini(&res->lr_reference);
1157                 /* We have taken lr_lvb_mutex. Drop it. */
1158                 mutex_unlock(&res->lr_lvb_mutex);
1159                 OBD_SLAB_FREE(res, ldlm_resource_slab, sizeof *res);
1160
1161                 res = cfs_hlist_entry(hnode, struct ldlm_resource, lr_hash);
1162                 /* Synchronize with regard to resource creation. */
1163                 if (ns->ns_lvbo && ns->ns_lvbo->lvbo_init) {
1164                         mutex_lock(&res->lr_lvb_mutex);
1165                         mutex_unlock(&res->lr_lvb_mutex);
1166                 }
1167
1168                 if (unlikely(res->lr_lvb_len < 0)) {
1169                         ldlm_resource_putref(res);
1170                         res = NULL;
1171                 }
1172                 return res;
1173         }
1174         /* We won! Let's add the resource. */
1175         cfs_hash_bd_add_locked(ns->ns_rs_hash, &bd, &res->lr_hash);
1176         if (cfs_hash_bd_count_get(&bd) == 1)
1177                 ns_refcount = ldlm_namespace_get_return(ns);
1178
1179         cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1180         if (ns->ns_lvbo && ns->ns_lvbo->lvbo_init) {
1181                 int rc;
1182
1183                 OBD_FAIL_TIMEOUT(OBD_FAIL_LDLM_CREATE_RESOURCE, 2);
1184                 rc = ns->ns_lvbo->lvbo_init(res);
1185                 if (rc < 0) {
1186                         CERROR("%s: lvbo_init failed for resource "LPX64":"
1187                                LPX64": rc = %d\n", ns->ns_obd->obd_name,
1188                                name->name[0], name->name[1], rc);
1189                         if (res->lr_lvb_data) {
1190                                 OBD_FREE(res->lr_lvb_data, res->lr_lvb_len);
1191                                 res->lr_lvb_data = NULL;
1192                         }
1193                         res->lr_lvb_len = rc;
1194                         mutex_unlock(&res->lr_lvb_mutex);
1195                         ldlm_resource_putref(res);
1196                         return NULL;
1197                 }
1198         }
1199
1200         /* We create resource with locked lr_lvb_mutex. */
1201         mutex_unlock(&res->lr_lvb_mutex);
1202
1203         /* Let's see if we happened to be the very first resource in this
1204          * namespace. If so, and this is a client namespace, we need to move
1205          * the namespace into the active namespaces list to be patrolled by
1206          * the ldlm_poold. */
1207         if (ns_is_client(ns) && ns_refcount == 1) {
1208                 mutex_lock(ldlm_namespace_lock(LDLM_NAMESPACE_CLIENT));
1209                 ldlm_namespace_move_to_active_locked(ns, LDLM_NAMESPACE_CLIENT);
1210                 mutex_unlock(ldlm_namespace_lock(LDLM_NAMESPACE_CLIENT));
1211         }
1212
1213         return res;
1214 }
1215 EXPORT_SYMBOL(ldlm_resource_get);
1216
1217 struct ldlm_resource *ldlm_resource_getref(struct ldlm_resource *res)
1218 {
1219         LASSERT(res != NULL);
1220         LASSERT(res != LP_POISON);
1221         cfs_atomic_inc(&res->lr_refcount);
1222         CDEBUG(D_INFO, "getref res: %p count: %d\n", res,
1223                cfs_atomic_read(&res->lr_refcount));
1224         return res;
1225 }
1226
1227 static void __ldlm_resource_putref_final(cfs_hash_bd_t *bd,
1228                                          struct ldlm_resource *res)
1229 {
1230         struct ldlm_ns_bucket *nsb = res->lr_ns_bucket;
1231
1232         if (!cfs_list_empty(&res->lr_granted)) {
1233                 ldlm_resource_dump(D_ERROR, res);
1234                 LBUG();
1235         }
1236
1237         if (!cfs_list_empty(&res->lr_converting)) {
1238                 ldlm_resource_dump(D_ERROR, res);
1239                 LBUG();
1240         }
1241
1242         if (!cfs_list_empty(&res->lr_waiting)) {
1243                 ldlm_resource_dump(D_ERROR, res);
1244                 LBUG();
1245         }
1246
1247         cfs_hash_bd_del_locked(nsb->nsb_namespace->ns_rs_hash,
1248                                bd, &res->lr_hash);
1249         lu_ref_fini(&res->lr_reference);
1250         if (cfs_hash_bd_count_get(bd) == 0)
1251                 ldlm_namespace_put(nsb->nsb_namespace);
1252 }
1253
1254 /* Returns 1 if the resource was freed, 0 if it remains. */
1255 int ldlm_resource_putref(struct ldlm_resource *res)
1256 {
1257         struct ldlm_namespace *ns = ldlm_res_to_ns(res);
1258         cfs_hash_bd_t   bd;
1259
1260         LASSERT_ATOMIC_GT_LT(&res->lr_refcount, 0, LI_POISON);
1261         CDEBUG(D_INFO, "putref res: %p count: %d\n",
1262                res, cfs_atomic_read(&res->lr_refcount) - 1);
1263
1264         cfs_hash_bd_get(ns->ns_rs_hash, &res->lr_name, &bd);
1265         if (cfs_hash_bd_dec_and_lock(ns->ns_rs_hash, &bd, &res->lr_refcount)) {
1266                 __ldlm_resource_putref_final(&bd, res);
1267                 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1268                 if (ns->ns_lvbo && ns->ns_lvbo->lvbo_free)
1269                         ns->ns_lvbo->lvbo_free(res);
1270                 OBD_SLAB_FREE(res, ldlm_resource_slab, sizeof *res);
1271                 return 1;
1272         }
1273         return 0;
1274 }
1275 EXPORT_SYMBOL(ldlm_resource_putref);
1276
1277 /* Returns 1 if the resource was freed, 0 if it remains. */
1278 int ldlm_resource_putref_locked(struct ldlm_resource *res)
1279 {
1280         struct ldlm_namespace *ns = ldlm_res_to_ns(res);
1281
1282         LASSERT_ATOMIC_GT_LT(&res->lr_refcount, 0, LI_POISON);
1283         CDEBUG(D_INFO, "putref res: %p count: %d\n",
1284                res, cfs_atomic_read(&res->lr_refcount) - 1);
1285
1286         if (cfs_atomic_dec_and_test(&res->lr_refcount)) {
1287                 cfs_hash_bd_t bd;
1288
1289                 cfs_hash_bd_get(ldlm_res_to_ns(res)->ns_rs_hash,
1290                                 &res->lr_name, &bd);
1291                 __ldlm_resource_putref_final(&bd, res);
1292                 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1293                 /* NB: ns_rs_hash is created with CFS_HASH_NO_ITEMREF,
1294                  * so we should never be here while calling cfs_hash_del,
1295                  * cfs_hash_for_each_nolock is the only case we can get
1296                  * here, which is safe to release cfs_hash_bd_lock.
1297                  */
1298                 if (ns->ns_lvbo && ns->ns_lvbo->lvbo_free)
1299                         ns->ns_lvbo->lvbo_free(res);
1300                 OBD_SLAB_FREE(res, ldlm_resource_slab, sizeof *res);
1301
1302                 cfs_hash_bd_lock(ns->ns_rs_hash, &bd, 1);
1303                 return 1;
1304         }
1305         return 0;
1306 }
1307
1308 /**
1309  * Add a lock into a given resource into specified lock list.
1310  */
1311 void ldlm_resource_add_lock(struct ldlm_resource *res, cfs_list_t *head,
1312                             struct ldlm_lock *lock)
1313 {
1314         check_res_locked(res);
1315
1316         LDLM_DEBUG(lock, "About to add this lock:\n");
1317
1318         if (lock->l_flags & LDLM_FL_DESTROYED) {
1319                 CDEBUG(D_OTHER, "Lock destroyed, not adding to resource\n");
1320                 return;
1321         }
1322
1323         LASSERT(cfs_list_empty(&lock->l_res_link));
1324
1325         cfs_list_add_tail(&lock->l_res_link, head);
1326 }
1327
1328 /**
1329  * Insert a lock into resource after specified lock.
1330  *
1331  * Obtain resource description from the lock we are inserting after.
1332  */
1333 void ldlm_resource_insert_lock_after(struct ldlm_lock *original,
1334                                      struct ldlm_lock *new)
1335 {
1336         struct ldlm_resource *res = original->l_resource;
1337
1338         check_res_locked(res);
1339
1340         ldlm_resource_dump(D_INFO, res);
1341         LDLM_DEBUG(new, "About to insert this lock after %p:\n", original);
1342
1343         if (new->l_flags & LDLM_FL_DESTROYED) {
1344                 CDEBUG(D_OTHER, "Lock destroyed, not adding to resource\n");
1345                 goto out;
1346         }
1347
1348         LASSERT(cfs_list_empty(&new->l_res_link));
1349
1350         cfs_list_add(&new->l_res_link, &original->l_res_link);
1351  out:;
1352 }
1353
1354 void ldlm_resource_unlink_lock(struct ldlm_lock *lock)
1355 {
1356         int type = lock->l_resource->lr_type;
1357
1358         check_res_locked(lock->l_resource);
1359         if (type == LDLM_IBITS || type == LDLM_PLAIN)
1360                 ldlm_unlink_lock_skiplist(lock);
1361         else if (type == LDLM_EXTENT)
1362                 ldlm_extent_unlink_lock(lock);
1363         cfs_list_del_init(&lock->l_res_link);
1364 }
1365 EXPORT_SYMBOL(ldlm_resource_unlink_lock);
1366
1367 void ldlm_res2desc(struct ldlm_resource *res, struct ldlm_resource_desc *desc)
1368 {
1369         desc->lr_type = res->lr_type;
1370         desc->lr_name = res->lr_name;
1371 }
1372
1373 /**
1374  * Print information about all locks in all namespaces on this node to debug
1375  * log.
1376  */
1377 void ldlm_dump_all_namespaces(ldlm_side_t client, int level)
1378 {
1379         cfs_list_t *tmp;
1380
1381         if (!((libcfs_debug | D_ERROR) & level))
1382                 return;
1383
1384         mutex_lock(ldlm_namespace_lock(client));
1385
1386         cfs_list_for_each(tmp, ldlm_namespace_list(client)) {
1387                 struct ldlm_namespace *ns;
1388                 ns = cfs_list_entry(tmp, struct ldlm_namespace, ns_list_chain);
1389                 ldlm_namespace_dump(level, ns);
1390         }
1391
1392         mutex_unlock(ldlm_namespace_lock(client));
1393 }
1394 EXPORT_SYMBOL(ldlm_dump_all_namespaces);
1395
1396 static int ldlm_res_hash_dump(cfs_hash_t *hs, cfs_hash_bd_t *bd,
1397                               cfs_hlist_node_t *hnode, void *arg)
1398 {
1399         struct ldlm_resource *res = cfs_hash_object(hs, hnode);
1400         int    level = (int)(unsigned long)arg;
1401
1402         lock_res(res);
1403         ldlm_resource_dump(level, res);
1404         unlock_res(res);
1405
1406         return 0;
1407 }
1408
1409 /**
1410  * Print information about all locks in this namespace on this node to debug
1411  * log.
1412  */
1413 void ldlm_namespace_dump(int level, struct ldlm_namespace *ns)
1414 {
1415         if (!((libcfs_debug | D_ERROR) & level))
1416                 return;
1417
1418         CDEBUG(level, "--- Namespace: %s (rc: %d, side: %s)\n",
1419                ldlm_ns_name(ns), cfs_atomic_read(&ns->ns_bref),
1420                ns_is_client(ns) ? "client" : "server");
1421
1422         if (cfs_time_before(cfs_time_current(), ns->ns_next_dump))
1423                 return;
1424
1425         cfs_hash_for_each_nolock(ns->ns_rs_hash,
1426                                  ldlm_res_hash_dump,
1427                                  (void *)(unsigned long)level);
1428         spin_lock(&ns->ns_lock);
1429         ns->ns_next_dump = cfs_time_shift(10);
1430         spin_unlock(&ns->ns_lock);
1431 }
1432 EXPORT_SYMBOL(ldlm_namespace_dump);
1433
1434 /**
1435  * Print information about all locks in this resource to debug log.
1436  */
1437 void ldlm_resource_dump(int level, struct ldlm_resource *res)
1438 {
1439         struct ldlm_lock *lock;
1440         unsigned int granted = 0;
1441
1442         CLASSERT(RES_NAME_SIZE == 4);
1443
1444         if (!((libcfs_debug | D_ERROR) & level))
1445                 return;
1446
1447         CDEBUG(level, "--- Resource: "DLDLMRES" (%p) refcount = %d\n",
1448                PLDLMRES(res), res, cfs_atomic_read(&res->lr_refcount));
1449
1450         if (!cfs_list_empty(&res->lr_granted)) {
1451                 CDEBUG(level, "Granted locks (in reverse order):\n");
1452                 cfs_list_for_each_entry_reverse(lock, &res->lr_granted,
1453                                                 l_res_link) {
1454                         LDLM_DEBUG_LIMIT(level, lock, "###");
1455                         if (!(level & D_CANTMASK) &&
1456                             ++granted > ldlm_dump_granted_max) {
1457                                 CDEBUG(level, "only dump %d granted locks to "
1458                                        "avoid DDOS.\n", granted);
1459                                 break;
1460                         }
1461                 }
1462         }
1463         if (!cfs_list_empty(&res->lr_converting)) {
1464                 CDEBUG(level, "Converting locks:\n");
1465                 cfs_list_for_each_entry(lock, &res->lr_converting, l_res_link)
1466                         LDLM_DEBUG_LIMIT(level, lock, "###");
1467         }
1468         if (!cfs_list_empty(&res->lr_waiting)) {
1469                 CDEBUG(level, "Waiting locks:\n");
1470                 cfs_list_for_each_entry(lock, &res->lr_waiting, l_res_link)
1471                         LDLM_DEBUG_LIMIT(level, lock, "###");
1472         }
1473 }