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 struct proc_dir_entry *ldlm_type_proc_dir = NULL;
  70 struct proc_dir_entry *ldlm_ns_proc_dir = NULL;
  71 struct proc_dir_entry *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 ssize_t
  81 lprocfs_dump_ns_seq_write(struct file *file, const char *buffer,
  82                           size_t count, loff_t *off)
  83 {
  84         ldlm_dump_all_namespaces(LDLM_NAMESPACE_SERVER, D_DLMTRACE);
  85         ldlm_dump_all_namespaces(LDLM_NAMESPACE_CLIENT, D_DLMTRACE);
  86         RETURN(count);
  87 }
  88 LPROC_SEQ_FOPS_WO_TYPE(ldlm, dump_ns);
  89
  90 LPROC_SEQ_FOPS_RW_TYPE(ldlm_rw, uint);
  91 LPROC_SEQ_FOPS_RO_TYPE(ldlm, uint);
  92
  93 int ldlm_proc_setup(void)
  94 {
  95         int rc;
  96         struct lprocfs_seq_vars list[] = {
  97                 { .name =       "dump_namespaces",
  98                   .fops =       &ldlm_dump_ns_fops,
  99                   .proc_mode =  0222 },
 100                 { .name =       "dump_granted_max",
 101                   .fops =       &ldlm_rw_uint_fops,
 102                   .data =       &ldlm_dump_granted_max },
 103                 { .name =       "cancel_unused_locks_before_replay",
 104                   .fops =       &ldlm_rw_uint_fops,
 105                   .data =       &ldlm_cancel_unused_locks_before_replay },
 106                 { NULL }};
 107         ENTRY;
 108         LASSERT(ldlm_ns_proc_dir == NULL);
 109
 110         ldlm_type_proc_dir = lprocfs_seq_register(OBD_LDLM_DEVICENAME,
 111                                                         proc_lustre_root,
 112                                                         NULL, NULL);
 113         if (IS_ERR(ldlm_type_proc_dir)) {
 114                 CERROR("LProcFS failed in ldlm-init\n");
 115                 rc = PTR_ERR(ldlm_type_proc_dir);
 116                 GOTO(err, rc);
 117         }
 118
 119         ldlm_ns_proc_dir = lprocfs_seq_register("namespaces",
 120                                                 ldlm_type_proc_dir,
 121                                                 NULL, NULL);
 122         if (IS_ERR(ldlm_ns_proc_dir)) {
 123                 CERROR("LProcFS failed in ldlm-init\n");
 124                 rc = PTR_ERR(ldlm_ns_proc_dir);
 125                 GOTO(err_type, rc);
 126         }
 127
 128         ldlm_svc_proc_dir = lprocfs_seq_register("services",
 129                                                 ldlm_type_proc_dir,
 130                                                 NULL, NULL);
 131         if (IS_ERR(ldlm_svc_proc_dir)) {
 132                 CERROR("LProcFS failed in ldlm-init\n");
 133                 rc = PTR_ERR(ldlm_svc_proc_dir);
 134                 GOTO(err_ns, rc);
 135         }
 136
 137         rc = lprocfs_seq_add_vars(ldlm_type_proc_dir, list, NULL);
 138         if (rc != 0) {
 139                 CERROR("LProcFS failed in ldlm-init\n");
 140                 GOTO(err_svc, rc);
 141         }
 142
 143         RETURN(0);
 144
 145 err_svc:
 146         lprocfs_remove(&ldlm_svc_proc_dir);
 147 err_ns:
 148         lprocfs_remove(&ldlm_ns_proc_dir);
 149 err_type:
 150         lprocfs_remove(&ldlm_type_proc_dir);
 151 err:
 152         ldlm_svc_proc_dir = NULL;
 153         RETURN(rc);
 154 }
 155
 156 void ldlm_proc_cleanup(void)
 157 {
 158         if (ldlm_svc_proc_dir)
 159                 lprocfs_remove(&ldlm_svc_proc_dir);
 160
 161         if (ldlm_ns_proc_dir)
 162                 lprocfs_remove(&ldlm_ns_proc_dir);
 163
 164         if (ldlm_type_proc_dir)
 165                 lprocfs_remove(&ldlm_type_proc_dir);
 166 }
 167
 168 static int lprocfs_ns_resources_seq_show(struct seq_file *m, void *v)
 169 {
 170         struct ldlm_namespace   *ns  = m->private;
 171         __u64                   res = 0;
 172         cfs_hash_bd_t           bd;
 173         int                     i;
 174
 175         /* result is not strictly consistant */
 176         cfs_hash_for_each_bucket(ns->ns_rs_hash, &bd, i)
 177                 res += cfs_hash_bd_count_get(&bd);
 178         return lprocfs_u64_seq_show(m, &res);
 179 }
 180 LPROC_SEQ_FOPS_RO(lprocfs_ns_resources);
 181
 182 static int lprocfs_ns_locks_seq_show(struct seq_file *m, void *v)
 183 {
 184         struct ldlm_namespace   *ns = m->private;
 185         __u64                   locks;
 186
 187         locks = lprocfs_stats_collector(ns->ns_stats, LDLM_NSS_LOCKS,
 188                                         LPROCFS_FIELDS_FLAGS_SUM);
 189         return lprocfs_u64_seq_show(m, &locks);
 190 }
 191 LPROC_SEQ_FOPS_RO(lprocfs_ns_locks);
 192
 193 static int lprocfs_lru_size_seq_show(struct seq_file *m, void *v)
 194 {
 195         struct ldlm_namespace *ns = m->private;
 196         __u32 *nr = &ns->ns_max_unused;
 197
 198         if (ns_connect_lru_resize(ns))
 199                 nr = &ns->ns_nr_unused;
 200         return lprocfs_uint_seq_show(m, nr);
 201 }
 202
 203 static ssize_t lprocfs_lru_size_seq_write(struct file *file, const char *buffer,
 204                                           size_t count, loff_t *off)
 205 {
 206         struct ldlm_namespace *ns = ((struct seq_file *)file->private_data)->private;
 207         char dummy[MAX_STRING_SIZE + 1], *end;
 208         unsigned long tmp;
 209         int lru_resize;
 210
 211         dummy[MAX_STRING_SIZE] = '\0';
 212         if (copy_from_user(dummy, buffer, MAX_STRING_SIZE))
 213                 return -EFAULT;
 214
 215         if (strncmp(dummy, "clear", 5) == 0) {
 216                 CDEBUG(D_DLMTRACE,
 217                        "dropping all unused locks from namespace %s\n",
 218                        ldlm_ns_name(ns));
 219                 if (ns_connect_lru_resize(ns)) {
 220                         int canceled, unused  = ns->ns_nr_unused;
 221
 222                         /* Try to cancel all @ns_nr_unused locks. */
 223                         canceled = ldlm_cancel_lru(ns, unused, 0,
 224                                                    LDLM_CANCEL_PASSED);
 225                         if (canceled < unused) {
 226                                 CDEBUG(D_DLMTRACE,
 227                                        "not all requested locks are canceled, "
 228                                        "requested: %d, canceled: %d\n", unused,
 229                                        canceled);
 230                                 return -EINVAL;
 231                         }
 232                 } else {
 233                         tmp = ns->ns_max_unused;
 234                         ns->ns_max_unused = 0;
 235                         ldlm_cancel_lru(ns, 0, 0, LDLM_CANCEL_PASSED);
 236                         ns->ns_max_unused = tmp;
 237                 }
 238                 return count;
 239         }
 240
 241         tmp = simple_strtoul(dummy, &end, 0);
 242         if (dummy == end) {
 243                 CERROR("invalid value written\n");
 244                 return -EINVAL;
 245         }
 246         lru_resize = (tmp == 0);
 247
 248         if (ns_connect_lru_resize(ns)) {
 249                 if (!lru_resize)
 250                         ns->ns_max_unused = (unsigned int)tmp;
 251
 252                 if (tmp > ns->ns_nr_unused)
 253                         tmp = ns->ns_nr_unused;
 254                 tmp = ns->ns_nr_unused - tmp;
 255
 256                 CDEBUG(D_DLMTRACE,
 257                        "changing namespace %s unused locks from %u to %u\n",
 258                        ldlm_ns_name(ns), ns->ns_nr_unused,
 259                        (unsigned int)tmp);
 260                 ldlm_cancel_lru(ns, tmp, LCF_ASYNC, LDLM_CANCEL_PASSED);
 261
 262                 if (!lru_resize) {
 263                         CDEBUG(D_DLMTRACE,
 264                                "disable lru_resize for namespace %s\n",
 265                                ldlm_ns_name(ns));
 266                         ns->ns_connect_flags &= ~OBD_CONNECT_LRU_RESIZE;
 267                 }
 268         } else {
 269                 CDEBUG(D_DLMTRACE,
 270                        "changing namespace %s max_unused from %u to %u\n",
 271                        ldlm_ns_name(ns), ns->ns_max_unused,
 272                        (unsigned int)tmp);
 273                 ns->ns_max_unused = (unsigned int)tmp;
 274                 ldlm_cancel_lru(ns, 0, LCF_ASYNC, LDLM_CANCEL_PASSED);
 275
 276                 /* Make sure that LRU resize was originally supported before
 277                  * turning it on here. */
 278                 if (lru_resize &&
 279                     (ns->ns_orig_connect_flags & OBD_CONNECT_LRU_RESIZE)) {
 280                         CDEBUG(D_DLMTRACE,
 281                                "enable lru_resize for namespace %s\n",
 282                                ldlm_ns_name(ns));
 283                         ns->ns_connect_flags |= OBD_CONNECT_LRU_RESIZE;
 284                 }
 285         }
 286
 287         return count;
 288 }
 289 LPROC_SEQ_FOPS(lprocfs_lru_size);
 290
 291 static int lprocfs_elc_seq_show(struct seq_file *m, void *v)
 292 {
 293         struct ldlm_namespace *ns = m->private;
 294         unsigned int supp = ns_connect_cancelset(ns);
 295
 296         return lprocfs_uint_seq_show(m, &supp);
 297 }
 298
 299 static ssize_t lprocfs_elc_seq_write(struct file *file, const char *buffer,
 300                                      size_t count, loff_t *off)
 301 {
 302         struct ldlm_namespace *ns = ((struct seq_file *)file->private_data)->private;
 303         unsigned int supp = -1;
 304         int rc;
 305
 306         rc = lprocfs_wr_uint(file, buffer, count, &supp);
 307         if (rc < 0)
 308                 return rc;
 309
 310         if (supp == 0)
 311                 ns->ns_connect_flags &= ~OBD_CONNECT_CANCELSET;
 312         else if (ns->ns_orig_connect_flags & OBD_CONNECT_CANCELSET)
 313                 ns->ns_connect_flags |= OBD_CONNECT_CANCELSET;
 314         return count;
 315 }
 316 LPROC_SEQ_FOPS(lprocfs_elc);
 317
 318 void ldlm_namespace_proc_unregister(struct ldlm_namespace *ns)
 319 {
 320         if (ns->ns_proc_dir_entry == NULL)
 321                 CERROR("dlm namespace %s has no procfs dir?\n",
 322                        ldlm_ns_name(ns));
 323         else
 324                 lprocfs_remove(&ns->ns_proc_dir_entry);
 325
 326         if (ns->ns_stats != NULL)
 327                 lprocfs_free_stats(&ns->ns_stats);
 328 }
 329
 330 int ldlm_namespace_proc_register(struct ldlm_namespace *ns)
 331 {
 332         struct lprocfs_seq_vars lock_vars[2];
 333         char lock_name[MAX_STRING_SIZE + 1];
 334         struct proc_dir_entry *ns_pde;
 335
 336         LASSERT(ns != NULL);
 337         LASSERT(ns->ns_rs_hash != NULL);
 338
 339         if (ns->ns_proc_dir_entry != NULL) {
 340                 ns_pde = ns->ns_proc_dir_entry;
 341         } else {
 342                 ns_pde = proc_mkdir(ldlm_ns_name(ns), ldlm_ns_proc_dir);
 343                 if (ns_pde == NULL)
 344                         return -ENOMEM;
 345                 ns->ns_proc_dir_entry = ns_pde;
 346         }
 347
 348         ns->ns_stats = lprocfs_alloc_stats(LDLM_NSS_LAST, 0);
 349         if (ns->ns_stats == NULL)
 350                 return -ENOMEM;
 351
 352         lprocfs_counter_init(ns->ns_stats, LDLM_NSS_LOCKS,
 353                              LPROCFS_CNTR_AVGMINMAX, "locks", "locks");
 354
 355         lock_name[MAX_STRING_SIZE] = '\0';
 356
 357         memset(lock_vars, 0, sizeof(lock_vars));
 358         lock_vars[0].name = lock_name;
 359
 360         ldlm_add_var(&lock_vars[0], ns_pde, "resource_count", ns,
 361                      &lprocfs_ns_resources_fops);
 362         ldlm_add_var(&lock_vars[0], ns_pde, "lock_count", ns,
 363                      &lprocfs_ns_locks_fops);
 364
 365         if (ns_is_client(ns)) {
 366                 ldlm_add_var(&lock_vars[0], ns_pde, "lock_unused_count",
 367                              &ns->ns_nr_unused, &ldlm_uint_fops);
 368                 ldlm_add_var(&lock_vars[0], ns_pde, "lru_size", ns,
 369                              &lprocfs_lru_size_fops);
 370                 ldlm_add_var(&lock_vars[0], ns_pde, "lru_max_age",
 371                              &ns->ns_max_age, &ldlm_rw_uint_fops);
 372                 ldlm_add_var(&lock_vars[0], ns_pde, "early_lock_cancel",
 373                              ns, &lprocfs_elc_fops);
 374         } else {
 375                 ldlm_add_var(&lock_vars[0], ns_pde, "ctime_age_limit",
 376                              &ns->ns_ctime_age_limit, &ldlm_rw_uint_fops);
 377                 ldlm_add_var(&lock_vars[0], ns_pde, "lock_timeouts",
 378                              &ns->ns_timeouts, &ldlm_uint_fops);
 379                 ldlm_add_var(&lock_vars[0], ns_pde, "max_nolock_bytes",
 380                              &ns->ns_max_nolock_size, &ldlm_rw_uint_fops);
 381                 ldlm_add_var(&lock_vars[0], ns_pde, "contention_seconds",
 382                              &ns->ns_contention_time, &ldlm_rw_uint_fops);
 383                 ldlm_add_var(&lock_vars[0], ns_pde, "contended_locks",
 384                              &ns->ns_contended_locks, &ldlm_rw_uint_fops);
 385                 ldlm_add_var(&lock_vars[0], ns_pde, "max_parallel_ast",
 386                              &ns->ns_max_parallel_ast, &ldlm_rw_uint_fops);
 387         }
 388         return 0;
 389 }
 390 #undef MAX_STRING_SIZE
 391 #else /* LPROCFS */
 392
 393 #define ldlm_namespace_proc_unregister(ns)      ({;})
 394 #define ldlm_namespace_proc_register(ns)        ({0;})
 395
 396 #endif /* LPROCFS */
 397
 398 static unsigned ldlm_res_hop_hash(cfs_hash_t *hs,
 399                                   const void *key, unsigned mask)
 400 {
 401         const struct ldlm_res_id     *id  = key;
 402         unsigned                val = 0;
 403         unsigned                i;
 404
 405         for (i = 0; i < RES_NAME_SIZE; i++)
 406                 val += id->name[i];
 407         return val & mask;
 408 }
 409
 410 static unsigned ldlm_res_hop_fid_hash(cfs_hash_t *hs,
 411                                       const void *key, unsigned mask)
 412 {
 413         const struct ldlm_res_id *id = key;
 414         struct lu_fid       fid;
 415         __u32               hash;
 416         __u32               val;
 417
 418         fid.f_seq = id->name[LUSTRE_RES_ID_SEQ_OFF];
 419         fid.f_oid = (__u32)id->name[LUSTRE_RES_ID_VER_OID_OFF];
 420         fid.f_ver = (__u32)(id->name[LUSTRE_RES_ID_VER_OID_OFF] >> 32);
 421
 422         hash = fid_flatten32(&fid);
 423         hash += (hash >> 4) + (hash << 12); /* mixing oid and seq */
 424         if (id->name[LUSTRE_RES_ID_HSH_OFF] != 0) {
 425                 val = id->name[LUSTRE_RES_ID_HSH_OFF];
 426                 hash += (val >> 5) + (val << 11);
 427         } else {
 428                 val = fid_oid(&fid);
 429         }
 430         hash = hash_long(hash, hs->hs_bkt_bits);
 431         /* give me another random factor */
 432         hash -= hash_long((unsigned long)hs, val % 11 + 3);
 433
 434         hash <<= hs->hs_cur_bits - hs->hs_bkt_bits;
 435         hash |= ldlm_res_hop_hash(hs, key, CFS_HASH_NBKT(hs) - 1);
 436
 437         return hash & mask;
 438 }
 439
 440 static void *ldlm_res_hop_key(cfs_hlist_node_t *hnode)
 441 {
 442         struct ldlm_resource   *res;
 443
 444         res = cfs_hlist_entry(hnode, struct ldlm_resource, lr_hash);
 445         return &res->lr_name;
 446 }
 447
 448 static int ldlm_res_hop_keycmp(const void *key, cfs_hlist_node_t *hnode)
 449 {
 450         struct ldlm_resource   *res;
 451
 452         res = cfs_hlist_entry(hnode, struct ldlm_resource, lr_hash);
 453         return ldlm_res_eq((const struct ldlm_res_id *)key,
 454                            (const struct ldlm_res_id *)&res->lr_name);
 455 }
 456
 457 static void *ldlm_res_hop_object(cfs_hlist_node_t *hnode)
 458 {
 459         return cfs_hlist_entry(hnode, struct ldlm_resource, lr_hash);
 460 }
 461
 462 static void ldlm_res_hop_get_locked(cfs_hash_t *hs, cfs_hlist_node_t *hnode)
 463 {
 464         struct ldlm_resource *res;
 465
 466         res = cfs_hlist_entry(hnode, struct ldlm_resource, lr_hash);
 467         ldlm_resource_getref(res);
 468 }
 469
 470 static void ldlm_res_hop_put_locked(cfs_hash_t *hs, cfs_hlist_node_t *hnode)
 471 {
 472         struct ldlm_resource *res;
 473
 474         res = cfs_hlist_entry(hnode, struct ldlm_resource, lr_hash);
 475         /* cfs_hash_for_each_nolock is the only chance we call it */
 476         ldlm_resource_putref_locked(res);
 477 }
 478
 479 static void ldlm_res_hop_put(cfs_hash_t *hs, cfs_hlist_node_t *hnode)
 480 {
 481         struct ldlm_resource *res;
 482
 483         res = cfs_hlist_entry(hnode, struct ldlm_resource, lr_hash);
 484         ldlm_resource_putref(res);
 485 }
 486
 487 cfs_hash_ops_t ldlm_ns_hash_ops = {
 488         .hs_hash        = ldlm_res_hop_hash,
 489         .hs_key         = ldlm_res_hop_key,
 490         .hs_keycmp      = ldlm_res_hop_keycmp,
 491         .hs_keycpy      = NULL,
 492         .hs_object      = ldlm_res_hop_object,
 493         .hs_get         = ldlm_res_hop_get_locked,
 494         .hs_put_locked  = ldlm_res_hop_put_locked,
 495         .hs_put         = ldlm_res_hop_put
 496 };
 497
 498 cfs_hash_ops_t ldlm_ns_fid_hash_ops = {
 499         .hs_hash        = ldlm_res_hop_fid_hash,
 500         .hs_key         = ldlm_res_hop_key,
 501         .hs_keycmp      = ldlm_res_hop_keycmp,
 502         .hs_keycpy      = NULL,
 503         .hs_object      = ldlm_res_hop_object,
 504         .hs_get         = ldlm_res_hop_get_locked,
 505         .hs_put_locked  = ldlm_res_hop_put_locked,
 506         .hs_put         = ldlm_res_hop_put
 507 };
 508
 509 typedef struct {
 510         ldlm_ns_type_t  nsd_type;
 511         /** hash bucket bits */
 512         unsigned        nsd_bkt_bits;
 513         /** hash bits */
 514         unsigned        nsd_all_bits;
 515         /** hash operations */
 516         cfs_hash_ops_t *nsd_hops;
 517 } ldlm_ns_hash_def_t;
 518
 519 ldlm_ns_hash_def_t ldlm_ns_hash_defs[] =
 520 {
 521         {
 522                 .nsd_type       = LDLM_NS_TYPE_MDC,
 523                 .nsd_bkt_bits   = 11,
 524                 .nsd_all_bits   = 16,
 525                 .nsd_hops       = &ldlm_ns_fid_hash_ops,
 526         },
 527         {
 528                 .nsd_type       = LDLM_NS_TYPE_MDT,
 529                 .nsd_bkt_bits   = 14,
 530                 .nsd_all_bits   = 21,
 531                 .nsd_hops       = &ldlm_ns_fid_hash_ops,
 532         },
 533         {
 534                 .nsd_type       = LDLM_NS_TYPE_OSC,
 535                 .nsd_bkt_bits   = 8,
 536                 .nsd_all_bits   = 12,
 537                 .nsd_hops       = &ldlm_ns_hash_ops,
 538         },
 539         {
 540                 .nsd_type       = LDLM_NS_TYPE_OST,
 541                 .nsd_bkt_bits   = 11,
 542                 .nsd_all_bits   = 17,
 543                 .nsd_hops       = &ldlm_ns_hash_ops,
 544         },
 545         {
 546                 .nsd_type       = LDLM_NS_TYPE_MGC,
 547                 .nsd_bkt_bits   = 4,
 548                 .nsd_all_bits   = 4,
 549                 .nsd_hops       = &ldlm_ns_hash_ops,
 550         },
 551         {
 552                 .nsd_type       = LDLM_NS_TYPE_MGT,
 553                 .nsd_bkt_bits   = 4,
 554                 .nsd_all_bits   = 4,
 555                 .nsd_hops       = &ldlm_ns_hash_ops,
 556         },
 557         {
 558                 .nsd_type       = LDLM_NS_TYPE_UNKNOWN,
 559         },
 560 };
 561
 562 /**
 563  * Create and initialize new empty namespace.
 564  */
 565 struct ldlm_namespace *ldlm_namespace_new(struct obd_device *obd, char *name,
 566                                           ldlm_side_t client,
 567                                           ldlm_appetite_t apt,
 568                                           ldlm_ns_type_t ns_type)
 569 {
 570         struct ldlm_namespace *ns = NULL;
 571         struct ldlm_ns_bucket *nsb;
 572         ldlm_ns_hash_def_t    *nsd;
 573         cfs_hash_bd_t          bd;
 574         int                    idx;
 575         int                    rc;
 576         ENTRY;
 577
 578         LASSERT(obd != NULL);
 579
 580         rc = ldlm_get_ref();
 581         if (rc) {
 582                 CERROR("ldlm_get_ref failed: %d\n", rc);
 583                 RETURN(NULL);
 584         }
 585
 586         for (idx = 0;;idx++) {
 587                 nsd = &ldlm_ns_hash_defs[idx];
 588                 if (nsd->nsd_type == LDLM_NS_TYPE_UNKNOWN) {
 589                         CERROR("Unknown type %d for ns %s\n", ns_type, name);
 590                         GOTO(out_ref, NULL);
 591                 }
 592
 593                 if (nsd->nsd_type == ns_type)
 594                         break;
 595         }
 596
 597         OBD_ALLOC_PTR(ns);
 598         if (!ns)
 599                 GOTO(out_ref, NULL);
 600
 601         ns->ns_rs_hash = cfs_hash_create(name,
 602                                          nsd->nsd_all_bits, nsd->nsd_all_bits,
 603                                          nsd->nsd_bkt_bits, sizeof(*nsb),
 604                                          CFS_HASH_MIN_THETA,
 605                                          CFS_HASH_MAX_THETA,
 606                                          nsd->nsd_hops,
 607                                          CFS_HASH_DEPTH |
 608                                          CFS_HASH_BIGNAME |
 609                                          CFS_HASH_SPIN_BKTLOCK |
 610                                          CFS_HASH_NO_ITEMREF);
 611         if (ns->ns_rs_hash == NULL)
 612                 GOTO(out_ns, NULL);
 613
 614         cfs_hash_for_each_bucket(ns->ns_rs_hash, &bd, idx) {
 615                 nsb = cfs_hash_bd_extra_get(ns->ns_rs_hash, &bd);
 616                 at_init(&nsb->nsb_at_estimate, ldlm_enqueue_min, 0);
 617                 nsb->nsb_namespace = ns;
 618         }
 619
 620         ns->ns_obd      = obd;
 621         ns->ns_appetite = apt;
 622         ns->ns_client   = client;
 623
 624         CFS_INIT_LIST_HEAD(&ns->ns_list_chain);
 625         CFS_INIT_LIST_HEAD(&ns->ns_unused_list);
 626         spin_lock_init(&ns->ns_lock);
 627         atomic_set(&ns->ns_bref, 0);
 628         init_waitqueue_head(&ns->ns_waitq);
 629
 630         ns->ns_max_nolock_size    = NS_DEFAULT_MAX_NOLOCK_BYTES;
 631         ns->ns_contention_time    = NS_DEFAULT_CONTENTION_SECONDS;
 632         ns->ns_contended_locks    = NS_DEFAULT_CONTENDED_LOCKS;
 633
 634         ns->ns_max_parallel_ast   = LDLM_DEFAULT_PARALLEL_AST_LIMIT;
 635         ns->ns_nr_unused          = 0;
 636         ns->ns_max_unused         = LDLM_DEFAULT_LRU_SIZE;
 637         ns->ns_max_age            = LDLM_DEFAULT_MAX_ALIVE;
 638         ns->ns_ctime_age_limit    = LDLM_CTIME_AGE_LIMIT;
 639         ns->ns_timeouts           = 0;
 640         ns->ns_orig_connect_flags = 0;
 641         ns->ns_connect_flags      = 0;
 642         ns->ns_stopping           = 0;
 643         rc = ldlm_namespace_proc_register(ns);
 644         if (rc != 0) {
 645                 CERROR("Can't initialize ns proc, rc %d\n", rc);
 646                 GOTO(out_hash, rc);
 647         }
 648
 649         idx = ldlm_namespace_nr_read(client);
 650         rc = ldlm_pool_init(&ns->ns_pool, ns, idx, client);
 651         if (rc) {
 652                 CERROR("Can't initialize lock pool, rc %d\n", rc);
 653                 GOTO(out_proc, rc);
 654         }
 655
 656         ldlm_namespace_register(ns, client);
 657         RETURN(ns);
 658 out_proc:
 659         ldlm_namespace_proc_unregister(ns);
 660         ldlm_namespace_cleanup(ns, 0);
 661 out_hash:
 662         cfs_hash_putref(ns->ns_rs_hash);
 663 out_ns:
 664         OBD_FREE_PTR(ns);
 665 out_ref:
 666         ldlm_put_ref();
 667         RETURN(NULL);
 668 }
 669 EXPORT_SYMBOL(ldlm_namespace_new);
 670
 671 extern struct ldlm_lock *ldlm_lock_get(struct ldlm_lock *lock);
 672
 673 /**
 674  * Cancel and destroy all locks on a resource.
 675  *
 676  * If flags contains FL_LOCAL_ONLY, don't try to tell the server, just
 677  * clean up.  This is currently only used for recovery, and we make
 678  * certain assumptions as a result--notably, that we shouldn't cancel
 679  * locks with refs.
 680  */
 681 static void cleanup_resource(struct ldlm_resource *res, cfs_list_t *q,
 682                              __u64 flags)
 683 {
 684         cfs_list_t *tmp;
 685         int rc = 0, client = ns_is_client(ldlm_res_to_ns(res));
 686         bool local_only = !!(flags & LDLM_FL_LOCAL_ONLY);
 687
 688         do {
 689                 struct ldlm_lock *lock = NULL;
 690
 691                 /* First, we look for non-cleaned-yet lock
 692                  * all cleaned locks are marked by CLEANED flag. */
 693                 lock_res(res);
 694                 cfs_list_for_each(tmp, q) {
 695                         lock = cfs_list_entry(tmp, struct ldlm_lock,
 696                                               l_res_link);
 697                         if (ldlm_is_cleaned(lock)) {
 698                                 lock = NULL;
 699                                 continue;
 700                         }
 701                         LDLM_LOCK_GET(lock);
 702                         ldlm_set_cleaned(lock);
 703                         break;
 704                 }
 705
 706                 if (lock == NULL) {
 707                         unlock_res(res);
 708                         break;
 709                 }
 710
 711                 /* Set CBPENDING so nothing in the cancellation path
 712                  * can match this lock. */
 713                 ldlm_set_cbpending(lock);
 714                 ldlm_set_failed(lock);
 715                 lock->l_flags |= flags;
 716
 717                 /* ... without sending a CANCEL message for local_only. */
 718                 if (local_only)
 719                         ldlm_set_local_only(lock);
 720
 721                 if (local_only && (lock->l_readers || lock->l_writers)) {
 722                         /* This is a little bit gross, but much better than the
 723                          * alternative: pretend that we got a blocking AST from
 724                          * the server, so that when the lock is decref'd, it
 725                          * will go away ... */
 726                         unlock_res(res);
 727                         LDLM_DEBUG(lock, "setting FL_LOCAL_ONLY");
 728                         if (lock->l_flags & LDLM_FL_FAIL_LOC) {
 729                                 schedule_timeout_and_set_state(
 730                                         TASK_UNINTERRUPTIBLE,
 731                                         cfs_time_seconds(4));
 732                                 set_current_state(TASK_RUNNING);
 733                         }
 734                         if (lock->l_completion_ast)
 735                                 lock->l_completion_ast(lock,
 736                                                        LDLM_FL_FAILED, NULL);
 737                         LDLM_LOCK_RELEASE(lock);
 738                         continue;
 739                 }
 740
 741                 if (client) {
 742                         struct lustre_handle lockh;
 743
 744                         unlock_res(res);
 745                         ldlm_lock2handle(lock, &lockh);
 746                         rc = ldlm_cli_cancel(&lockh, LCF_ASYNC);
 747                         if (rc)
 748                                 CERROR("ldlm_cli_cancel: %d\n", rc);
 749                 } else {
 750                         ldlm_resource_unlink_lock(lock);
 751                         unlock_res(res);
 752                         LDLM_DEBUG(lock, "Freeing a lock still held by a "
 753                                    "client node");
 754                         ldlm_lock_destroy(lock);
 755                 }
 756                 LDLM_LOCK_RELEASE(lock);
 757         } while (1);
 758 }
 759
 760 static int ldlm_resource_clean(cfs_hash_t *hs, cfs_hash_bd_t *bd,
 761                                cfs_hlist_node_t *hnode, void *arg)
 762 {
 763         struct ldlm_resource *res = cfs_hash_object(hs, hnode);
 764         __u64 flags = *(__u64 *)arg;
 765
 766         cleanup_resource(res, &res->lr_granted, flags);
 767         cleanup_resource(res, &res->lr_converting, flags);
 768         cleanup_resource(res, &res->lr_waiting, flags);
 769
 770         return 0;
 771 }
 772
 773 static int ldlm_resource_complain(cfs_hash_t *hs, cfs_hash_bd_t *bd,
 774                                   cfs_hlist_node_t *hnode, void *arg)
 775 {
 776         struct ldlm_resource  *res = cfs_hash_object(hs, hnode);
 777
 778         lock_res(res);
 779         CERROR("%s: namespace resource "DLDLMRES" (%p) refcount nonzero "
 780                "(%d) after lock cleanup; forcing cleanup.\n",
 781                ldlm_ns_name(ldlm_res_to_ns(res)), PLDLMRES(res), res,
 782                atomic_read(&res->lr_refcount) - 1);
 783
 784         ldlm_resource_dump(D_ERROR, res);
 785         unlock_res(res);
 786         return 0;
 787 }
 788
 789 /**
 790  * Cancel and destroy all locks in the namespace.
 791  *
 792  * Typically used during evictions when server notified client that it was
 793  * evicted and all of its state needs to be destroyed.
 794  * Also used during shutdown.
 795  */
 796 int ldlm_namespace_cleanup(struct ldlm_namespace *ns, __u64 flags)
 797 {
 798         if (ns == NULL) {
 799                 CDEBUG(D_INFO, "NULL ns, skipping cleanup\n");
 800                 return ELDLM_OK;
 801         }
 802
 803         cfs_hash_for_each_nolock(ns->ns_rs_hash, ldlm_resource_clean, &flags);
 804         cfs_hash_for_each_nolock(ns->ns_rs_hash, ldlm_resource_complain, NULL);
 805         return ELDLM_OK;
 806 }
 807 EXPORT_SYMBOL(ldlm_namespace_cleanup);
 808
 809 /**
 810  * Attempts to free namespace.
 811  *
 812  * Only used when namespace goes away, like during an unmount.
 813  */
 814 static int __ldlm_namespace_free(struct ldlm_namespace *ns, int force)
 815 {
 816         ENTRY;
 817
 818         /* At shutdown time, don't call the cancellation callback */
 819         ldlm_namespace_cleanup(ns, force ? LDLM_FL_LOCAL_ONLY : 0);
 820
 821         if (atomic_read(&ns->ns_bref) > 0) {
 822                 struct l_wait_info lwi = LWI_INTR(LWI_ON_SIGNAL_NOOP, NULL);
 823                 int rc;
 824                 CDEBUG(D_DLMTRACE,
 825                        "dlm namespace %s free waiting on refcount %d\n",
 826                        ldlm_ns_name(ns), atomic_read(&ns->ns_bref));
 827 force_wait:
 828                 if (force)
 829                         lwi = LWI_TIMEOUT(obd_timeout * HZ / 4, NULL, NULL);
 830
 831                 rc = l_wait_event(ns->ns_waitq,
 832                                   atomic_read(&ns->ns_bref) == 0, &lwi);
 833
 834                 /* Forced cleanups should be able to reclaim all references,
 835                  * so it's safe to wait forever... we can't leak locks... */
 836                 if (force && rc == -ETIMEDOUT) {
 837                         LCONSOLE_ERROR("Forced cleanup waiting for %s "
 838                                        "namespace with %d resources in use, "
 839                                        "(rc=%d)\n", ldlm_ns_name(ns),
 840                                        atomic_read(&ns->ns_bref), rc);
 841                         GOTO(force_wait, rc);
 842                 }
 843
 844                 if (atomic_read(&ns->ns_bref)) {
 845                         LCONSOLE_ERROR("Cleanup waiting for %s namespace "
 846                                        "with %d resources in use, (rc=%d)\n",
 847                                        ldlm_ns_name(ns),
 848                                        atomic_read(&ns->ns_bref), rc);
 849                         RETURN(ELDLM_NAMESPACE_EXISTS);
 850                 }
 851                 CDEBUG(D_DLMTRACE, "dlm namespace %s free done waiting\n",
 852                        ldlm_ns_name(ns));
 853         }
 854
 855         RETURN(ELDLM_OK);
 856 }
 857
 858 /**
 859  * Performs various cleanups for passed \a ns to make it drop refc and be
 860  * ready for freeing. Waits for refc == 0.
 861  *
 862  * The following is done:
 863  * (0) Unregister \a ns from its list to make inaccessible for potential
 864  * users like pools thread and others;
 865  * (1) Clear all locks in \a ns.
 866  */
 867 void ldlm_namespace_free_prior(struct ldlm_namespace *ns,
 868                                struct obd_import *imp,
 869                                int force)
 870 {
 871         int rc;
 872         ENTRY;
 873         if (!ns) {
 874                 EXIT;
 875                 return;
 876         }
 877
 878         spin_lock(&ns->ns_lock);
 879         ns->ns_stopping = 1;
 880         spin_unlock(&ns->ns_lock);
 881
 882         /*
 883          * Can fail with -EINTR when force == 0 in which case try harder.
 884          */
 885         rc = __ldlm_namespace_free(ns, force);
 886         if (rc != ELDLM_OK) {
 887                 if (imp) {
 888                         ptlrpc_disconnect_import(imp, 0);
 889                         ptlrpc_invalidate_import(imp);
 890                 }
 891
 892                 /*
 893                  * With all requests dropped and the import inactive
 894                  * we are gaurenteed all reference will be dropped.
 895                  */
 896                 rc = __ldlm_namespace_free(ns, 1);
 897                 LASSERT(rc == 0);
 898         }
 899         EXIT;
 900 }
 901
 902 /**
 903  * Performs freeing memory structures related to \a ns. This is only done
 904  * when ldlm_namespce_free_prior() successfully removed all resources
 905  * referencing \a ns and its refc == 0.
 906  */
 907 void ldlm_namespace_free_post(struct ldlm_namespace *ns)
 908 {
 909         ENTRY;
 910         if (!ns) {
 911                 EXIT;
 912                 return;
 913         }
 914
 915         /* Make sure that nobody can find this ns in its list. */
 916         ldlm_namespace_unregister(ns, ns->ns_client);
 917         /* Fini pool _before_ parent proc dir is removed. This is important as
 918          * ldlm_pool_fini() removes own proc dir which is child to @dir.
 919          * Removing it after @dir may cause oops. */
 920         ldlm_pool_fini(&ns->ns_pool);
 921
 922         ldlm_namespace_proc_unregister(ns);
 923         cfs_hash_putref(ns->ns_rs_hash);
 924         /* Namespace \a ns should be not on list at this time, otherwise
 925          * this will cause issues related to using freed \a ns in poold
 926          * thread. */
 927         LASSERT(cfs_list_empty(&ns->ns_list_chain));
 928         OBD_FREE_PTR(ns);
 929         ldlm_put_ref();
 930         EXIT;
 931 }
 932
 933 /**
 934  * Cleanup the resource, and free namespace.
 935  * bug 12864:
 936  * Deadlock issue:
 937  * proc1: destroy import
 938  *        class_disconnect_export(grab cl_sem) ->
 939  *              -> ldlm_namespace_free ->
 940  *              -> lprocfs_remove(grab _lprocfs_lock).
 941  * proc2: read proc info
 942  *        lprocfs_fops_read(grab _lprocfs_lock) ->
 943  *              -> osc_rd_active, etc(grab cl_sem).
 944  *
 945  * So that I have to split the ldlm_namespace_free into two parts - the first
 946  * part ldlm_namespace_free_prior is used to cleanup the resource which is
 947  * being used; the 2nd part ldlm_namespace_free_post is used to unregister the
 948  * lprocfs entries, and then free memory. It will be called w/o cli->cl_sem
 949  * held.
 950  */
 951 void ldlm_namespace_free(struct ldlm_namespace *ns,
 952                          struct obd_import *imp,
 953                          int force)
 954 {
 955         ldlm_namespace_free_prior(ns, imp, force);
 956         ldlm_namespace_free_post(ns);
 957 }
 958 EXPORT_SYMBOL(ldlm_namespace_free);
 959
 960 void ldlm_namespace_get(struct ldlm_namespace *ns)
 961 {
 962         atomic_inc(&ns->ns_bref);
 963 }
 964 EXPORT_SYMBOL(ldlm_namespace_get);
 965
 966 /* This is only for callers that care about refcount */
 967 int ldlm_namespace_get_return(struct ldlm_namespace *ns)
 968 {
 969         return atomic_inc_return(&ns->ns_bref);
 970 }
 971
 972 void ldlm_namespace_put(struct ldlm_namespace *ns)
 973 {
 974         if (atomic_dec_and_lock(&ns->ns_bref, &ns->ns_lock)) {
 975                 wake_up(&ns->ns_waitq);
 976                 spin_unlock(&ns->ns_lock);
 977         }
 978 }
 979 EXPORT_SYMBOL(ldlm_namespace_put);
 980
 981 /** Register \a ns in the list of namespaces */
 982 void ldlm_namespace_register(struct ldlm_namespace *ns, ldlm_side_t client)
 983 {
 984         mutex_lock(ldlm_namespace_lock(client));
 985         LASSERT(cfs_list_empty(&ns->ns_list_chain));
 986         cfs_list_add(&ns->ns_list_chain, ldlm_namespace_inactive_list(client));
 987         ldlm_namespace_nr_inc(client);
 988         mutex_unlock(ldlm_namespace_lock(client));
 989 }
 990
 991 /** Unregister \a ns from the list of namespaces. */
 992 void ldlm_namespace_unregister(struct ldlm_namespace *ns, ldlm_side_t client)
 993 {
 994         mutex_lock(ldlm_namespace_lock(client));
 995         LASSERT(!cfs_list_empty(&ns->ns_list_chain));
 996         /* Some asserts and possibly other parts of the code are still
 997          * using list_empty(&ns->ns_list_chain). This is why it is
 998          * important to use list_del_init() here. */
 999         cfs_list_del_init(&ns->ns_list_chain);
1000         ldlm_namespace_nr_dec(client);
1001         mutex_unlock(ldlm_namespace_lock(client));
1002 }
1003
1004 /** Should be called with ldlm_namespace_lock(client) taken. */
1005 void ldlm_namespace_move_to_active_locked(struct ldlm_namespace *ns,
1006                                        ldlm_side_t client)
1007 {
1008         LASSERT(!cfs_list_empty(&ns->ns_list_chain));
1009         LASSERT(mutex_is_locked(ldlm_namespace_lock(client)));
1010         cfs_list_move_tail(&ns->ns_list_chain, ldlm_namespace_list(client));
1011 }
1012
1013 /** Should be called with ldlm_namespace_lock(client) taken. */
1014 void ldlm_namespace_move_to_inactive_locked(struct ldlm_namespace *ns,
1015                                          ldlm_side_t client)
1016 {
1017         LASSERT(!cfs_list_empty(&ns->ns_list_chain));
1018         LASSERT(mutex_is_locked(ldlm_namespace_lock(client)));
1019         cfs_list_move_tail(&ns->ns_list_chain,
1020                            ldlm_namespace_inactive_list(client));
1021 }
1022
1023 /** Should be called with ldlm_namespace_lock(client) taken. */
1024 struct ldlm_namespace *ldlm_namespace_first_locked(ldlm_side_t client)
1025 {
1026         LASSERT(mutex_is_locked(ldlm_namespace_lock(client)));
1027         LASSERT(!cfs_list_empty(ldlm_namespace_list(client)));
1028         return container_of(ldlm_namespace_list(client)->next,
1029                             struct ldlm_namespace, ns_list_chain);
1030 }
1031
1032 /** Create and initialize new resource. */
1033 static struct ldlm_resource *ldlm_resource_new(void)
1034 {
1035         struct ldlm_resource *res;
1036         int idx;
1037
1038         OBD_SLAB_ALLOC_PTR_GFP(res, ldlm_resource_slab, GFP_NOFS);
1039         if (res == NULL)
1040                 return NULL;
1041
1042         CFS_INIT_LIST_HEAD(&res->lr_granted);
1043         CFS_INIT_LIST_HEAD(&res->lr_converting);
1044         CFS_INIT_LIST_HEAD(&res->lr_waiting);
1045
1046         /* Initialize interval trees for each lock mode. */
1047         for (idx = 0; idx < LCK_MODE_NUM; idx++) {
1048                 res->lr_itree[idx].lit_size = 0;
1049                 res->lr_itree[idx].lit_mode = 1 << idx;
1050                 res->lr_itree[idx].lit_root = NULL;
1051         }
1052
1053         atomic_set(&res->lr_refcount, 1);
1054         spin_lock_init(&res->lr_lock);
1055         lu_ref_init(&res->lr_reference);
1056
1057         /* The creator of the resource must unlock the mutex after LVB
1058          * initialization. */
1059         mutex_init(&res->lr_lvb_mutex);
1060         mutex_lock(&res->lr_lvb_mutex);
1061
1062         return res;
1063 }
1064
1065 /**
1066  * Return a reference to resource with given name, creating it if necessary.
1067  * Args: namespace with ns_lock unlocked
1068  * Locks: takes and releases NS hash-lock and res->lr_lock
1069  * Returns: referenced, unlocked ldlm_resource or NULL
1070  */
1071 struct ldlm_resource *
1072 ldlm_resource_get(struct ldlm_namespace *ns, struct ldlm_resource *parent,
1073                   const struct ldlm_res_id *name, ldlm_type_t type, int create)
1074 {
1075         cfs_hlist_node_t     *hnode;
1076         struct ldlm_resource *res;
1077         cfs_hash_bd_t         bd;
1078         __u64                 version;
1079         int                   ns_refcount = 0;
1080
1081         LASSERT(ns != NULL);
1082         LASSERT(parent == NULL);
1083         LASSERT(ns->ns_rs_hash != NULL);
1084         LASSERT(name->name[0] != 0);
1085
1086         cfs_hash_bd_get_and_lock(ns->ns_rs_hash, (void *)name, &bd, 0);
1087         hnode = cfs_hash_bd_lookup_locked(ns->ns_rs_hash, &bd, (void *)name);
1088         if (hnode != NULL) {
1089                 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 0);
1090                 res = cfs_hlist_entry(hnode, struct ldlm_resource, lr_hash);
1091                 /* Synchronize with regard to resource creation. */
1092                 if (ns->ns_lvbo && ns->ns_lvbo->lvbo_init) {
1093                         mutex_lock(&res->lr_lvb_mutex);
1094                         mutex_unlock(&res->lr_lvb_mutex);
1095                 }
1096
1097                 if (unlikely(res->lr_lvb_len < 0)) {
1098                         ldlm_resource_putref(res);
1099                         res = NULL;
1100                 }
1101                 return res;
1102         }
1103
1104         version = cfs_hash_bd_version_get(&bd);
1105         cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 0);
1106
1107         if (create == 0)
1108                 return NULL;
1109
1110         LASSERTF(type >= LDLM_MIN_TYPE && type < LDLM_MAX_TYPE,
1111                  "type: %d\n", type);
1112         res = ldlm_resource_new();
1113         if (!res)
1114                 return NULL;
1115
1116         res->lr_ns_bucket  = cfs_hash_bd_extra_get(ns->ns_rs_hash, &bd);
1117         res->lr_name       = *name;
1118         res->lr_type       = type;
1119         res->lr_most_restr = LCK_NL;
1120
1121         cfs_hash_bd_lock(ns->ns_rs_hash, &bd, 1);
1122         hnode = (version == cfs_hash_bd_version_get(&bd)) ?  NULL :
1123                 cfs_hash_bd_lookup_locked(ns->ns_rs_hash, &bd, (void *)name);
1124
1125         if (hnode != NULL) {
1126                 /* Someone won the race and already added the resource. */
1127                 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1128                 /* Clean lu_ref for failed resource. */
1129                 lu_ref_fini(&res->lr_reference);
1130                 /* We have taken lr_lvb_mutex. Drop it. */
1131                 mutex_unlock(&res->lr_lvb_mutex);
1132                 OBD_SLAB_FREE(res, ldlm_resource_slab, sizeof *res);
1133
1134                 res = cfs_hlist_entry(hnode, struct ldlm_resource, lr_hash);
1135                 /* Synchronize with regard to resource creation. */
1136                 if (ns->ns_lvbo && ns->ns_lvbo->lvbo_init) {
1137                         mutex_lock(&res->lr_lvb_mutex);
1138                         mutex_unlock(&res->lr_lvb_mutex);
1139                 }
1140
1141                 if (unlikely(res->lr_lvb_len < 0)) {
1142                         ldlm_resource_putref(res);
1143                         res = NULL;
1144                 }
1145                 return res;
1146         }
1147         /* We won! Let's add the resource. */
1148         cfs_hash_bd_add_locked(ns->ns_rs_hash, &bd, &res->lr_hash);
1149         if (cfs_hash_bd_count_get(&bd) == 1)
1150                 ns_refcount = ldlm_namespace_get_return(ns);
1151
1152         cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1153         if (ns->ns_lvbo && ns->ns_lvbo->lvbo_init) {
1154                 int rc;
1155
1156                 OBD_FAIL_TIMEOUT(OBD_FAIL_LDLM_CREATE_RESOURCE, 2);
1157                 rc = ns->ns_lvbo->lvbo_init(res);
1158                 if (rc < 0) {
1159                         CERROR("%s: lvbo_init failed for resource "LPX64":"
1160                                LPX64": rc = %d\n", ns->ns_obd->obd_name,
1161                                name->name[0], name->name[1], rc);
1162                         if (res->lr_lvb_data) {
1163                                 OBD_FREE(res->lr_lvb_data, res->lr_lvb_len);
1164                                 res->lr_lvb_data = NULL;
1165                         }
1166                         res->lr_lvb_len = rc;
1167                         mutex_unlock(&res->lr_lvb_mutex);
1168                         ldlm_resource_putref(res);
1169                         return NULL;
1170                 }
1171         }
1172
1173         /* We create resource with locked lr_lvb_mutex. */
1174         mutex_unlock(&res->lr_lvb_mutex);
1175
1176         /* Let's see if we happened to be the very first resource in this
1177          * namespace. If so, and this is a client namespace, we need to move
1178          * the namespace into the active namespaces list to be patrolled by
1179          * the ldlm_poold. */
1180         if (ns_is_client(ns) && ns_refcount == 1) {
1181                 mutex_lock(ldlm_namespace_lock(LDLM_NAMESPACE_CLIENT));
1182                 ldlm_namespace_move_to_active_locked(ns, LDLM_NAMESPACE_CLIENT);
1183                 mutex_unlock(ldlm_namespace_lock(LDLM_NAMESPACE_CLIENT));
1184         }
1185
1186         return res;
1187 }
1188 EXPORT_SYMBOL(ldlm_resource_get);
1189
1190 struct ldlm_resource *ldlm_resource_getref(struct ldlm_resource *res)
1191 {
1192         LASSERT(res != NULL);
1193         LASSERT(res != LP_POISON);
1194         atomic_inc(&res->lr_refcount);
1195         CDEBUG(D_INFO, "getref res: %p count: %d\n", res,
1196                atomic_read(&res->lr_refcount));
1197         return res;
1198 }
1199
1200 static void __ldlm_resource_putref_final(cfs_hash_bd_t *bd,
1201                                          struct ldlm_resource *res)
1202 {
1203         struct ldlm_ns_bucket *nsb = res->lr_ns_bucket;
1204
1205         if (!cfs_list_empty(&res->lr_granted)) {
1206                 ldlm_resource_dump(D_ERROR, res);
1207                 LBUG();
1208         }
1209
1210         if (!cfs_list_empty(&res->lr_converting)) {
1211                 ldlm_resource_dump(D_ERROR, res);
1212                 LBUG();
1213         }
1214
1215         if (!cfs_list_empty(&res->lr_waiting)) {
1216                 ldlm_resource_dump(D_ERROR, res);
1217                 LBUG();
1218         }
1219
1220         cfs_hash_bd_del_locked(nsb->nsb_namespace->ns_rs_hash,
1221                                bd, &res->lr_hash);
1222         lu_ref_fini(&res->lr_reference);
1223         if (cfs_hash_bd_count_get(bd) == 0)
1224                 ldlm_namespace_put(nsb->nsb_namespace);
1225 }
1226
1227 /* Returns 1 if the resource was freed, 0 if it remains. */
1228 int ldlm_resource_putref(struct ldlm_resource *res)
1229 {
1230         struct ldlm_namespace *ns = ldlm_res_to_ns(res);
1231         cfs_hash_bd_t   bd;
1232
1233         LASSERT_ATOMIC_GT_LT(&res->lr_refcount, 0, LI_POISON);
1234         CDEBUG(D_INFO, "putref res: %p count: %d\n",
1235                res, atomic_read(&res->lr_refcount) - 1);
1236
1237         cfs_hash_bd_get(ns->ns_rs_hash, &res->lr_name, &bd);
1238         if (cfs_hash_bd_dec_and_lock(ns->ns_rs_hash, &bd, &res->lr_refcount)) {
1239                 __ldlm_resource_putref_final(&bd, res);
1240                 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1241                 if (ns->ns_lvbo && ns->ns_lvbo->lvbo_free)
1242                         ns->ns_lvbo->lvbo_free(res);
1243                 OBD_SLAB_FREE(res, ldlm_resource_slab, sizeof *res);
1244                 return 1;
1245         }
1246         return 0;
1247 }
1248 EXPORT_SYMBOL(ldlm_resource_putref);
1249
1250 /* Returns 1 if the resource was freed, 0 if it remains. */
1251 int ldlm_resource_putref_locked(struct ldlm_resource *res)
1252 {
1253         struct ldlm_namespace *ns = ldlm_res_to_ns(res);
1254
1255         LASSERT_ATOMIC_GT_LT(&res->lr_refcount, 0, LI_POISON);
1256         CDEBUG(D_INFO, "putref res: %p count: %d\n",
1257                res, atomic_read(&res->lr_refcount) - 1);
1258
1259         if (atomic_dec_and_test(&res->lr_refcount)) {
1260                 cfs_hash_bd_t bd;
1261
1262                 cfs_hash_bd_get(ldlm_res_to_ns(res)->ns_rs_hash,
1263                                 &res->lr_name, &bd);
1264                 __ldlm_resource_putref_final(&bd, res);
1265                 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1266                 /* NB: ns_rs_hash is created with CFS_HASH_NO_ITEMREF,
1267                  * so we should never be here while calling cfs_hash_del,
1268                  * cfs_hash_for_each_nolock is the only case we can get
1269                  * here, which is safe to release cfs_hash_bd_lock.
1270                  */
1271                 if (ns->ns_lvbo && ns->ns_lvbo->lvbo_free)
1272                         ns->ns_lvbo->lvbo_free(res);
1273                 OBD_SLAB_FREE(res, ldlm_resource_slab, sizeof *res);
1274
1275                 cfs_hash_bd_lock(ns->ns_rs_hash, &bd, 1);
1276                 return 1;
1277         }
1278         return 0;
1279 }
1280
1281 /**
1282  * Add a lock into a given resource into specified lock list.
1283  */
1284 void ldlm_resource_add_lock(struct ldlm_resource *res, cfs_list_t *head,
1285                             struct ldlm_lock *lock)
1286 {
1287         check_res_locked(res);
1288
1289         LDLM_DEBUG(lock, "About to add this lock:\n");
1290
1291         if (ldlm_is_destroyed(lock)) {
1292                 CDEBUG(D_OTHER, "Lock destroyed, not adding to resource\n");
1293                 return;
1294         }
1295
1296         LASSERT(cfs_list_empty(&lock->l_res_link));
1297
1298         cfs_list_add_tail(&lock->l_res_link, head);
1299 }
1300
1301 /**
1302  * Insert a lock into resource after specified lock.
1303  *
1304  * Obtain resource description from the lock we are inserting after.
1305  */
1306 void ldlm_resource_insert_lock_after(struct ldlm_lock *original,
1307                                      struct ldlm_lock *new)
1308 {
1309         struct ldlm_resource *res = original->l_resource;
1310
1311         check_res_locked(res);
1312
1313         ldlm_resource_dump(D_INFO, res);
1314         LDLM_DEBUG(new, "About to insert this lock after %p:\n", original);
1315
1316         if (ldlm_is_destroyed(new)) {
1317                 CDEBUG(D_OTHER, "Lock destroyed, not adding to resource\n");
1318                 goto out;
1319         }
1320
1321         LASSERT(cfs_list_empty(&new->l_res_link));
1322
1323         cfs_list_add(&new->l_res_link, &original->l_res_link);
1324  out:;
1325 }
1326
1327 void ldlm_resource_unlink_lock(struct ldlm_lock *lock)
1328 {
1329         int type = lock->l_resource->lr_type;
1330
1331         check_res_locked(lock->l_resource);
1332         if (type == LDLM_IBITS || type == LDLM_PLAIN)
1333                 ldlm_unlink_lock_skiplist(lock);
1334         else if (type == LDLM_EXTENT)
1335                 ldlm_extent_unlink_lock(lock);
1336         cfs_list_del_init(&lock->l_res_link);
1337 }
1338 EXPORT_SYMBOL(ldlm_resource_unlink_lock);
1339
1340 void ldlm_res2desc(struct ldlm_resource *res, struct ldlm_resource_desc *desc)
1341 {
1342         desc->lr_type = res->lr_type;
1343         desc->lr_name = res->lr_name;
1344 }
1345
1346 /**
1347  * Print information about all locks in all namespaces on this node to debug
1348  * log.
1349  */
1350 void ldlm_dump_all_namespaces(ldlm_side_t client, int level)
1351 {
1352         cfs_list_t *tmp;
1353
1354         if (!((libcfs_debug | D_ERROR) & level))
1355                 return;
1356
1357         mutex_lock(ldlm_namespace_lock(client));
1358
1359         cfs_list_for_each(tmp, ldlm_namespace_list(client)) {
1360                 struct ldlm_namespace *ns;
1361                 ns = cfs_list_entry(tmp, struct ldlm_namespace, ns_list_chain);
1362                 ldlm_namespace_dump(level, ns);
1363         }
1364
1365         mutex_unlock(ldlm_namespace_lock(client));
1366 }
1367 EXPORT_SYMBOL(ldlm_dump_all_namespaces);
1368
1369 static int ldlm_res_hash_dump(cfs_hash_t *hs, cfs_hash_bd_t *bd,
1370                               cfs_hlist_node_t *hnode, void *arg)
1371 {
1372         struct ldlm_resource *res = cfs_hash_object(hs, hnode);
1373         int    level = (int)(unsigned long)arg;
1374
1375         lock_res(res);
1376         ldlm_resource_dump(level, res);
1377         unlock_res(res);
1378
1379         return 0;
1380 }
1381
1382 /**
1383  * Print information about all locks in this namespace on this node to debug
1384  * log.
1385  */
1386 void ldlm_namespace_dump(int level, struct ldlm_namespace *ns)
1387 {
1388         if (!((libcfs_debug | D_ERROR) & level))
1389                 return;
1390
1391         CDEBUG(level, "--- Namespace: %s (rc: %d, side: %s)\n",
1392                ldlm_ns_name(ns), atomic_read(&ns->ns_bref),
1393                ns_is_client(ns) ? "client" : "server");
1394
1395         if (cfs_time_before(cfs_time_current(), ns->ns_next_dump))
1396                 return;
1397
1398         cfs_hash_for_each_nolock(ns->ns_rs_hash,
1399                                  ldlm_res_hash_dump,
1400                                  (void *)(unsigned long)level);
1401         spin_lock(&ns->ns_lock);
1402         ns->ns_next_dump = cfs_time_shift(10);
1403         spin_unlock(&ns->ns_lock);
1404 }
1405 EXPORT_SYMBOL(ldlm_namespace_dump);
1406
1407 /**
1408  * Print information about all locks in this resource to debug log.
1409  */
1410 void ldlm_resource_dump(int level, struct ldlm_resource *res)
1411 {
1412         struct ldlm_lock *lock;
1413         unsigned int granted = 0;
1414
1415         CLASSERT(RES_NAME_SIZE == 4);
1416
1417         if (!((libcfs_debug | D_ERROR) & level))
1418                 return;
1419
1420         CDEBUG(level, "--- Resource: "DLDLMRES" (%p) refcount = %d\n",
1421                PLDLMRES(res), res, atomic_read(&res->lr_refcount));
1422
1423         if (!cfs_list_empty(&res->lr_granted)) {
1424                 CDEBUG(level, "Granted locks (in reverse order):\n");
1425                 cfs_list_for_each_entry_reverse(lock, &res->lr_granted,
1426                                                 l_res_link) {
1427                         LDLM_DEBUG_LIMIT(level, lock, "###");
1428                         if (!(level & D_CANTMASK) &&
1429                             ++granted > ldlm_dump_granted_max) {
1430                                 CDEBUG(level, "only dump %d granted locks to "
1431                                        "avoid DDOS.\n", granted);
1432                                 break;
1433                         }
1434                 }
1435         }
1436         if (!cfs_list_empty(&res->lr_converting)) {
1437                 CDEBUG(level, "Converting locks:\n");
1438                 cfs_list_for_each_entry(lock, &res->lr_converting, l_res_link)
1439                         LDLM_DEBUG_LIMIT(level, lock, "###");
1440         }
1441         if (!cfs_list_empty(&res->lr_waiting)) {
1442                 CDEBUG(level, "Waiting locks:\n");
1443                 cfs_list_for_each_entry(lock, &res->lr_waiting, l_res_link)
1444                         LDLM_DEBUG_LIMIT(level, lock, "###");
1445         }
1446 }