drivers/staging/lustre/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, 2012, 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 #include "../include/lustre_dlm.h"
  44 #include "../include/lustre_fid.h"
  45 #include "../include/obd_class.h"
  46 #include "ldlm_internal.h"
  47
  48 struct kmem_cache *ldlm_resource_slab, *ldlm_lock_slab;
  49
  50 int ldlm_srv_namespace_nr = 0;
  51 int ldlm_cli_namespace_nr = 0;
  52
  53 struct mutex ldlm_srv_namespace_lock;
  54 LIST_HEAD(ldlm_srv_namespace_list);
  55
  56 struct mutex ldlm_cli_namespace_lock;
  57 /* Client Namespaces that have active resources in them.
  58  * Once all resources go away, ldlm_poold moves such namespaces to the
  59  * inactive list */
  60 LIST_HEAD(ldlm_cli_active_namespace_list);
  61 /* Client namespaces that don't have any locks in them */
  62 LIST_HEAD(ldlm_cli_inactive_namespace_list);
  63
  64 struct proc_dir_entry *ldlm_type_proc_dir = NULL;
  65 struct proc_dir_entry *ldlm_ns_proc_dir = NULL;
  66 struct proc_dir_entry *ldlm_svc_proc_dir = NULL;
  67
  68 extern unsigned int ldlm_cancel_unused_locks_before_replay;
  69
  70 /* during debug dump certain amount of granted locks for one resource to avoid
  71  * DDOS. */
  72 unsigned int ldlm_dump_granted_max = 256;
  73
  74 #if defined (CONFIG_PROC_FS)
  75 static ssize_t lprocfs_wr_dump_ns(struct file *file, const char *buffer,
  76                                   size_t count, loff_t *off)
  77 {
  78         ldlm_dump_all_namespaces(LDLM_NAMESPACE_SERVER, D_DLMTRACE);
  79         ldlm_dump_all_namespaces(LDLM_NAMESPACE_CLIENT, D_DLMTRACE);
  80         return count;
  81 }
  82 LPROC_SEQ_FOPS_WR_ONLY(ldlm, dump_ns);
  83
  84 LPROC_SEQ_FOPS_RW_TYPE(ldlm_rw, uint);
  85 LPROC_SEQ_FOPS_RO_TYPE(ldlm, uint);
  86
  87 int ldlm_proc_setup(void)
  88 {
  89         int rc;
  90         struct lprocfs_vars list[] = {
  91                 { "dump_namespaces", &ldlm_dump_ns_fops, NULL, 0222 },
  92                 { "dump_granted_max", &ldlm_rw_uint_fops,
  93                   &ldlm_dump_granted_max },
  94                 { "cancel_unused_locks_before_replay", &ldlm_rw_uint_fops,
  95                   &ldlm_cancel_unused_locks_before_replay },
  96                 { NULL }};
  97         LASSERT(ldlm_ns_proc_dir == NULL);
  98
  99         ldlm_type_proc_dir = lprocfs_register(OBD_LDLM_DEVICENAME,
 100                                               proc_lustre_root,
 101                                               NULL, NULL);
 102         if (IS_ERR(ldlm_type_proc_dir)) {
 103                 CERROR("LProcFS failed in ldlm-init\n");
 104                 rc = PTR_ERR(ldlm_type_proc_dir);
 105                 goto err;
 106         }
 107
 108         ldlm_ns_proc_dir = lprocfs_register("namespaces",
 109                                             ldlm_type_proc_dir,
 110                                             NULL, NULL);
 111         if (IS_ERR(ldlm_ns_proc_dir)) {
 112                 CERROR("LProcFS failed in ldlm-init\n");
 113                 rc = PTR_ERR(ldlm_ns_proc_dir);
 114                 goto err_type;
 115         }
 116
 117         ldlm_svc_proc_dir = lprocfs_register("services",
 118                                             ldlm_type_proc_dir,
 119                                             NULL, NULL);
 120         if (IS_ERR(ldlm_svc_proc_dir)) {
 121                 CERROR("LProcFS failed in ldlm-init\n");
 122                 rc = PTR_ERR(ldlm_svc_proc_dir);
 123                 goto err_ns;
 124         }
 125
 126         rc = lprocfs_add_vars(ldlm_type_proc_dir, list, NULL);
 127
 128         return 0;
 129
 130 err_ns:
 131         lprocfs_remove(&ldlm_ns_proc_dir);
 132 err_type:
 133         lprocfs_remove(&ldlm_type_proc_dir);
 134 err:
 135         ldlm_svc_proc_dir = NULL;
 136         ldlm_type_proc_dir = NULL;
 137         ldlm_ns_proc_dir = NULL;
 138         return rc;
 139 }
 140
 141 void ldlm_proc_cleanup(void)
 142 {
 143         if (ldlm_svc_proc_dir)
 144                 lprocfs_remove(&ldlm_svc_proc_dir);
 145
 146         if (ldlm_ns_proc_dir)
 147                 lprocfs_remove(&ldlm_ns_proc_dir);
 148
 149         if (ldlm_type_proc_dir)
 150                 lprocfs_remove(&ldlm_type_proc_dir);
 151
 152         ldlm_svc_proc_dir = NULL;
 153         ldlm_type_proc_dir = NULL;
 154         ldlm_ns_proc_dir = NULL;
 155 }
 156
 157 static int lprocfs_ns_resources_seq_show(struct seq_file *m, void *v)
 158 {
 159         struct ldlm_namespace *ns  = m->private;
 160         __u64             res = 0;
 161         struct cfs_hash_bd        bd;
 162         int                 i;
 163
 164         /* result is not strictly consistent */
 165         cfs_hash_for_each_bucket(ns->ns_rs_hash, &bd, i)
 166                 res += cfs_hash_bd_count_get(&bd);
 167         return lprocfs_rd_u64(m, &res);
 168 }
 169 LPROC_SEQ_FOPS_RO(lprocfs_ns_resources);
 170
 171 static int lprocfs_ns_locks_seq_show(struct seq_file *m, void *v)
 172 {
 173         struct ldlm_namespace *ns = m->private;
 174         __u64             locks;
 175
 176         locks = lprocfs_stats_collector(ns->ns_stats, LDLM_NSS_LOCKS,
 177                                         LPROCFS_FIELDS_FLAGS_SUM);
 178         return lprocfs_rd_u64(m, &locks);
 179 }
 180 LPROC_SEQ_FOPS_RO(lprocfs_ns_locks);
 181
 182 static int lprocfs_lru_size_seq_show(struct seq_file *m, void *v)
 183 {
 184         struct ldlm_namespace *ns = m->private;
 185         __u32 *nr = &ns->ns_max_unused;
 186
 187         if (ns_connect_lru_resize(ns))
 188                 nr = &ns->ns_nr_unused;
 189         return lprocfs_rd_uint(m, nr);
 190 }
 191
 192 static ssize_t lprocfs_lru_size_seq_write(struct file *file,
 193                                         const char __user *buffer,
 194                                         size_t count, loff_t *off)
 195 {
 196         struct ldlm_namespace *ns = ((struct seq_file *)file->private_data)->private;
 197         char dummy[MAX_STRING_SIZE + 1];
 198         unsigned long tmp;
 199         int lru_resize;
 200         int err;
 201
 202         dummy[MAX_STRING_SIZE] = '\0';
 203         if (copy_from_user(dummy, buffer, MAX_STRING_SIZE))
 204                 return -EFAULT;
 205
 206         if (strncmp(dummy, "clear", 5) == 0) {
 207                 CDEBUG(D_DLMTRACE,
 208                        "dropping all unused locks from namespace %s\n",
 209                        ldlm_ns_name(ns));
 210                 if (ns_connect_lru_resize(ns)) {
 211                         int canceled, unused  = ns->ns_nr_unused;
 212
 213                         /* Try to cancel all @ns_nr_unused locks. */
 214                         canceled = ldlm_cancel_lru(ns, unused, 0,
 215                                                    LDLM_CANCEL_PASSED);
 216                         if (canceled < unused) {
 217                                 CDEBUG(D_DLMTRACE,
 218                                        "not all requested locks are canceled, "
 219                                        "requested: %d, canceled: %d\n", unused,
 220                                        canceled);
 221                                 return -EINVAL;
 222                         }
 223                 } else {
 224                         tmp = ns->ns_max_unused;
 225                         ns->ns_max_unused = 0;
 226                         ldlm_cancel_lru(ns, 0, 0, LDLM_CANCEL_PASSED);
 227                         ns->ns_max_unused = tmp;
 228                 }
 229                 return count;
 230         }
 231
 232         err = kstrtoul(dummy, 10, &tmp);
 233         if (err != 0) {
 234                 CERROR("invalid value written\n");
 235                 return -EINVAL;
 236         }
 237         lru_resize = (tmp == 0);
 238
 239         if (ns_connect_lru_resize(ns)) {
 240                 if (!lru_resize)
 241                         ns->ns_max_unused = (unsigned int)tmp;
 242
 243                 if (tmp > ns->ns_nr_unused)
 244                         tmp = ns->ns_nr_unused;
 245                 tmp = ns->ns_nr_unused - tmp;
 246
 247                 CDEBUG(D_DLMTRACE,
 248                        "changing namespace %s unused locks from %u to %u\n",
 249                        ldlm_ns_name(ns), ns->ns_nr_unused,
 250                        (unsigned int)tmp);
 251                 ldlm_cancel_lru(ns, tmp, LCF_ASYNC, LDLM_CANCEL_PASSED);
 252
 253                 if (!lru_resize) {
 254                         CDEBUG(D_DLMTRACE,
 255                                "disable lru_resize for namespace %s\n",
 256                                ldlm_ns_name(ns));
 257                         ns->ns_connect_flags &= ~OBD_CONNECT_LRU_RESIZE;
 258                 }
 259         } else {
 260                 CDEBUG(D_DLMTRACE,
 261                        "changing namespace %s max_unused from %u to %u\n",
 262                        ldlm_ns_name(ns), ns->ns_max_unused,
 263                        (unsigned int)tmp);
 264                 ns->ns_max_unused = (unsigned int)tmp;
 265                 ldlm_cancel_lru(ns, 0, LCF_ASYNC, LDLM_CANCEL_PASSED);
 266
 267                 /* Make sure that LRU resize was originally supported before
 268                  * turning it on here. */
 269                 if (lru_resize &&
 270                     (ns->ns_orig_connect_flags & OBD_CONNECT_LRU_RESIZE)) {
 271                         CDEBUG(D_DLMTRACE,
 272                                "enable lru_resize for namespace %s\n",
 273                                ldlm_ns_name(ns));
 274                         ns->ns_connect_flags |= OBD_CONNECT_LRU_RESIZE;
 275                 }
 276         }
 277
 278         return count;
 279 }
 280 LPROC_SEQ_FOPS(lprocfs_lru_size);
 281
 282 static int lprocfs_elc_seq_show(struct seq_file *m, void *v)
 283 {
 284         struct ldlm_namespace *ns = m->private;
 285         unsigned int supp = ns_connect_cancelset(ns);
 286
 287         return lprocfs_rd_uint(m, &supp);
 288 }
 289
 290 static ssize_t lprocfs_elc_seq_write(struct file *file, const char *buffer,
 291                                  size_t count, loff_t *off)
 292 {
 293         struct ldlm_namespace *ns = ((struct seq_file *)file->private_data)->private;
 294         unsigned int supp = -1;
 295         int rc;
 296
 297         rc = lprocfs_wr_uint(file, buffer, count, &supp);
 298         if (rc < 0)
 299                 return rc;
 300
 301         if (supp == 0)
 302                 ns->ns_connect_flags &= ~OBD_CONNECT_CANCELSET;
 303         else if (ns->ns_orig_connect_flags & OBD_CONNECT_CANCELSET)
 304                 ns->ns_connect_flags |= OBD_CONNECT_CANCELSET;
 305         return count;
 306 }
 307 LPROC_SEQ_FOPS(lprocfs_elc);
 308
 309 void ldlm_namespace_proc_unregister(struct ldlm_namespace *ns)
 310 {
 311         if (ns->ns_proc_dir_entry == NULL)
 312                 CERROR("dlm namespace %s has no procfs dir?\n",
 313                        ldlm_ns_name(ns));
 314         else
 315                 lprocfs_remove(&ns->ns_proc_dir_entry);
 316
 317         if (ns->ns_stats != NULL)
 318                 lprocfs_free_stats(&ns->ns_stats);
 319 }
 320
 321 #define LDLM_NS_ADD_VAR(name, var, ops)                         \
 322         do {                                                    \
 323                 snprintf(lock_name, MAX_STRING_SIZE, name);     \
 324                 lock_vars[0].data = var;                        \
 325                 lock_vars[0].fops = ops;                        \
 326                 lprocfs_add_vars(ns_pde, lock_vars, NULL);      \
 327         } while (0)
 328
 329 int ldlm_namespace_proc_register(struct ldlm_namespace *ns)
 330 {
 331         struct lprocfs_vars lock_vars[2];
 332         char lock_name[MAX_STRING_SIZE + 1];
 333         struct proc_dir_entry *ns_pde;
 334
 335         LASSERT(ns != NULL);
 336         LASSERT(ns->ns_rs_hash != NULL);
 337
 338         if (ns->ns_proc_dir_entry != NULL) {
 339                 ns_pde = ns->ns_proc_dir_entry;
 340         } else {
 341                 ns_pde = proc_mkdir(ldlm_ns_name(ns), ldlm_ns_proc_dir);
 342                 if (ns_pde == NULL)
 343                         return -ENOMEM;
 344                 ns->ns_proc_dir_entry = ns_pde;
 345         }
 346
 347         ns->ns_stats = lprocfs_alloc_stats(LDLM_NSS_LAST, 0);
 348         if (ns->ns_stats == NULL)
 349                 return -ENOMEM;
 350
 351         lprocfs_counter_init(ns->ns_stats, LDLM_NSS_LOCKS,
 352                              LPROCFS_CNTR_AVGMINMAX, "locks", "locks");
 353
 354         lock_name[MAX_STRING_SIZE] = '\0';
 355
 356         memset(lock_vars, 0, sizeof(lock_vars));
 357         lock_vars[0].name = lock_name;
 358
 359         LDLM_NS_ADD_VAR("resource_count", ns, &lprocfs_ns_resources_fops);
 360         LDLM_NS_ADD_VAR("lock_count", ns, &lprocfs_ns_locks_fops);
 361
 362         if (ns_is_client(ns)) {
 363                 LDLM_NS_ADD_VAR("lock_unused_count", &ns->ns_nr_unused,
 364                                 &ldlm_uint_fops);
 365                 LDLM_NS_ADD_VAR("lru_size", ns, &lprocfs_lru_size_fops);
 366                 LDLM_NS_ADD_VAR("lru_max_age", &ns->ns_max_age,
 367                                 &ldlm_rw_uint_fops);
 368                 LDLM_NS_ADD_VAR("early_lock_cancel", ns, &lprocfs_elc_fops);
 369         } else {
 370                 LDLM_NS_ADD_VAR("ctime_age_limit", &ns->ns_ctime_age_limit,
 371                                 &ldlm_rw_uint_fops);
 372                 LDLM_NS_ADD_VAR("lock_timeouts", &ns->ns_timeouts,
 373                                 &ldlm_uint_fops);
 374                 LDLM_NS_ADD_VAR("max_nolock_bytes", &ns->ns_max_nolock_size,
 375                                 &ldlm_rw_uint_fops);
 376                 LDLM_NS_ADD_VAR("contention_seconds", &ns->ns_contention_time,
 377                                 &ldlm_rw_uint_fops);
 378                 LDLM_NS_ADD_VAR("contended_locks", &ns->ns_contended_locks,
 379                                 &ldlm_rw_uint_fops);
 380                 LDLM_NS_ADD_VAR("max_parallel_ast", &ns->ns_max_parallel_ast,
 381                                 &ldlm_rw_uint_fops);
 382         }
 383         return 0;
 384 }
 385 #undef MAX_STRING_SIZE
 386 #else /* CONFIG_PROC_FS */
 387
 388 #define ldlm_namespace_proc_unregister(ns)      ({;})
 389 #define ldlm_namespace_proc_register(ns)        ({0;})
 390
 391 #endif /* CONFIG_PROC_FS */
 392
 393 static unsigned ldlm_res_hop_hash(struct cfs_hash *hs,
 394                                   const void *key, unsigned mask)
 395 {
 396         const struct ldlm_res_id     *id  = key;
 397         unsigned                val = 0;
 398         unsigned                i;
 399
 400         for (i = 0; i < RES_NAME_SIZE; i++)
 401                 val += id->name[i];
 402         return val & mask;
 403 }
 404
 405 static unsigned ldlm_res_hop_fid_hash(struct cfs_hash *hs,
 406                                       const void *key, unsigned mask)
 407 {
 408         const struct ldlm_res_id *id = key;
 409         struct lu_fid       fid;
 410         __u32          hash;
 411         __u32          val;
 412
 413         fid.f_seq = id->name[LUSTRE_RES_ID_SEQ_OFF];
 414         fid.f_oid = (__u32)id->name[LUSTRE_RES_ID_VER_OID_OFF];
 415         fid.f_ver = (__u32)(id->name[LUSTRE_RES_ID_VER_OID_OFF] >> 32);
 416
 417         hash = fid_flatten32(&fid);
 418         hash += (hash >> 4) + (hash << 12); /* mixing oid and seq */
 419         if (id->name[LUSTRE_RES_ID_HSH_OFF] != 0) {
 420                 val = id->name[LUSTRE_RES_ID_HSH_OFF];
 421                 hash += (val >> 5) + (val << 11);
 422         } else {
 423                 val = fid_oid(&fid);
 424         }
 425         hash = hash_long(hash, hs->hs_bkt_bits);
 426         /* give me another random factor */
 427         hash -= hash_long((unsigned long)hs, val % 11 + 3);
 428
 429         hash <<= hs->hs_cur_bits - hs->hs_bkt_bits;
 430         hash |= ldlm_res_hop_hash(hs, key, CFS_HASH_NBKT(hs) - 1);
 431
 432         return hash & mask;
 433 }
 434
 435 static void *ldlm_res_hop_key(struct hlist_node *hnode)
 436 {
 437         struct ldlm_resource   *res;
 438
 439         res = hlist_entry(hnode, struct ldlm_resource, lr_hash);
 440         return &res->lr_name;
 441 }
 442
 443 static int ldlm_res_hop_keycmp(const void *key, struct hlist_node *hnode)
 444 {
 445         struct ldlm_resource   *res;
 446
 447         res = hlist_entry(hnode, struct ldlm_resource, lr_hash);
 448         return ldlm_res_eq((const struct ldlm_res_id *)key,
 449                            (const struct ldlm_res_id *)&res->lr_name);
 450 }
 451
 452 static void *ldlm_res_hop_object(struct hlist_node *hnode)
 453 {
 454         return hlist_entry(hnode, struct ldlm_resource, lr_hash);
 455 }
 456
 457 static void ldlm_res_hop_get_locked(struct cfs_hash *hs, struct hlist_node *hnode)
 458 {
 459         struct ldlm_resource *res;
 460
 461         res = hlist_entry(hnode, struct ldlm_resource, lr_hash);
 462         ldlm_resource_getref(res);
 463 }
 464
 465 static void ldlm_res_hop_put_locked(struct cfs_hash *hs, struct hlist_node *hnode)
 466 {
 467         struct ldlm_resource *res;
 468
 469         res = hlist_entry(hnode, struct ldlm_resource, lr_hash);
 470         /* cfs_hash_for_each_nolock is the only chance we call it */
 471         ldlm_resource_putref_locked(res);
 472 }
 473
 474 static void ldlm_res_hop_put(struct cfs_hash *hs, struct hlist_node *hnode)
 475 {
 476         struct ldlm_resource *res;
 477
 478         res = hlist_entry(hnode, struct ldlm_resource, lr_hash);
 479         ldlm_resource_putref(res);
 480 }
 481
 482 cfs_hash_ops_t ldlm_ns_hash_ops = {
 483         .hs_hash        = ldlm_res_hop_hash,
 484         .hs_key  = ldlm_res_hop_key,
 485         .hs_keycmp      = ldlm_res_hop_keycmp,
 486         .hs_keycpy      = NULL,
 487         .hs_object      = ldlm_res_hop_object,
 488         .hs_get  = ldlm_res_hop_get_locked,
 489         .hs_put_locked  = ldlm_res_hop_put_locked,
 490         .hs_put  = ldlm_res_hop_put
 491 };
 492
 493 cfs_hash_ops_t ldlm_ns_fid_hash_ops = {
 494         .hs_hash        = ldlm_res_hop_fid_hash,
 495         .hs_key  = ldlm_res_hop_key,
 496         .hs_keycmp      = ldlm_res_hop_keycmp,
 497         .hs_keycpy      = NULL,
 498         .hs_object      = ldlm_res_hop_object,
 499         .hs_get  = ldlm_res_hop_get_locked,
 500         .hs_put_locked  = ldlm_res_hop_put_locked,
 501         .hs_put  = ldlm_res_hop_put
 502 };
 503
 504 struct ldlm_ns_hash_def {
 505         ldlm_ns_type_t  nsd_type;
 506         /** hash bucket bits */
 507         unsigned        nsd_bkt_bits;
 508         /** hash bits */
 509         unsigned        nsd_all_bits;
 510         /** hash operations */
 511         cfs_hash_ops_t *nsd_hops;
 512 };
 513
 514 struct ldlm_ns_hash_def ldlm_ns_hash_defs[] = {
 515         {
 516                 .nsd_type       = LDLM_NS_TYPE_MDC,
 517                 .nsd_bkt_bits   = 11,
 518                 .nsd_all_bits   = 16,
 519                 .nsd_hops       = &ldlm_ns_fid_hash_ops,
 520         },
 521         {
 522                 .nsd_type       = LDLM_NS_TYPE_MDT,
 523                 .nsd_bkt_bits   = 14,
 524                 .nsd_all_bits   = 21,
 525                 .nsd_hops       = &ldlm_ns_fid_hash_ops,
 526         },
 527         {
 528                 .nsd_type       = LDLM_NS_TYPE_OSC,
 529                 .nsd_bkt_bits   = 8,
 530                 .nsd_all_bits   = 12,
 531                 .nsd_hops       = &ldlm_ns_hash_ops,
 532         },
 533         {
 534                 .nsd_type       = LDLM_NS_TYPE_OST,
 535                 .nsd_bkt_bits   = 11,
 536                 .nsd_all_bits   = 17,
 537                 .nsd_hops       = &ldlm_ns_hash_ops,
 538         },
 539         {
 540                 .nsd_type       = LDLM_NS_TYPE_MGC,
 541                 .nsd_bkt_bits   = 4,
 542                 .nsd_all_bits   = 4,
 543                 .nsd_hops       = &ldlm_ns_hash_ops,
 544         },
 545         {
 546                 .nsd_type       = LDLM_NS_TYPE_MGT,
 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_UNKNOWN,
 553         },
 554 };
 555
 556 /**
 557  * Create and initialize new empty namespace.
 558  */
 559 struct ldlm_namespace *ldlm_namespace_new(struct obd_device *obd, char *name,
 560                                           ldlm_side_t client,
 561                                           ldlm_appetite_t apt,
 562                                           ldlm_ns_type_t ns_type)
 563 {
 564         struct ldlm_namespace *ns = NULL;
 565         struct ldlm_ns_bucket *nsb;
 566         struct ldlm_ns_hash_def    *nsd;
 567         struct cfs_hash_bd        bd;
 568         int                 idx;
 569         int                 rc;
 570
 571         LASSERT(obd != NULL);
 572
 573         rc = ldlm_get_ref();
 574         if (rc) {
 575                 CERROR("ldlm_get_ref failed: %d\n", rc);
 576                 return NULL;
 577         }
 578
 579         for (idx = 0;;idx++) {
 580                 nsd = &ldlm_ns_hash_defs[idx];
 581                 if (nsd->nsd_type == LDLM_NS_TYPE_UNKNOWN) {
 582                         CERROR("Unknown type %d for ns %s\n", ns_type, name);
 583                         goto out_ref;
 584                 }
 585
 586                 if (nsd->nsd_type == ns_type)
 587                         break;
 588         }
 589
 590         OBD_ALLOC_PTR(ns);
 591         if (!ns)
 592                 goto out_ref;
 593
 594         ns->ns_rs_hash = cfs_hash_create(name,
 595                                          nsd->nsd_all_bits, nsd->nsd_all_bits,
 596                                          nsd->nsd_bkt_bits, sizeof(*nsb),
 597                                          CFS_HASH_MIN_THETA,
 598                                          CFS_HASH_MAX_THETA,
 599                                          nsd->nsd_hops,
 600                                          CFS_HASH_DEPTH |
 601                                          CFS_HASH_BIGNAME |
 602                                          CFS_HASH_SPIN_BKTLOCK |
 603                                          CFS_HASH_NO_ITEMREF);
 604         if (ns->ns_rs_hash == NULL)
 605                 goto out_ns;
 606
 607         cfs_hash_for_each_bucket(ns->ns_rs_hash, &bd, idx) {
 608                 nsb = cfs_hash_bd_extra_get(ns->ns_rs_hash, &bd);
 609                 at_init(&nsb->nsb_at_estimate, ldlm_enqueue_min, 0);
 610                 nsb->nsb_namespace = ns;
 611         }
 612
 613         ns->ns_obd      = obd;
 614         ns->ns_appetite = apt;
 615         ns->ns_client   = client;
 616
 617         INIT_LIST_HEAD(&ns->ns_list_chain);
 618         INIT_LIST_HEAD(&ns->ns_unused_list);
 619         spin_lock_init(&ns->ns_lock);
 620         atomic_set(&ns->ns_bref, 0);
 621         init_waitqueue_head(&ns->ns_waitq);
 622
 623         ns->ns_max_nolock_size    = NS_DEFAULT_MAX_NOLOCK_BYTES;
 624         ns->ns_contention_time    = NS_DEFAULT_CONTENTION_SECONDS;
 625         ns->ns_contended_locks    = NS_DEFAULT_CONTENDED_LOCKS;
 626
 627         ns->ns_max_parallel_ast   = LDLM_DEFAULT_PARALLEL_AST_LIMIT;
 628         ns->ns_nr_unused          = 0;
 629         ns->ns_max_unused        = LDLM_DEFAULT_LRU_SIZE;
 630         ns->ns_max_age      = LDLM_DEFAULT_MAX_ALIVE;
 631         ns->ns_ctime_age_limit    = LDLM_CTIME_AGE_LIMIT;
 632         ns->ns_timeouts    = 0;
 633         ns->ns_orig_connect_flags = 0;
 634         ns->ns_connect_flags      = 0;
 635         ns->ns_stopping    = 0;
 636         rc = ldlm_namespace_proc_register(ns);
 637         if (rc != 0) {
 638                 CERROR("Can't initialize ns proc, rc %d\n", rc);
 639                 goto out_hash;
 640         }
 641
 642         idx = ldlm_namespace_nr_read(client);
 643         rc = ldlm_pool_init(&ns->ns_pool, ns, idx, client);
 644         if (rc) {
 645                 CERROR("Can't initialize lock pool, rc %d\n", rc);
 646                 goto out_proc;
 647         }
 648
 649         ldlm_namespace_register(ns, client);
 650         return ns;
 651 out_proc:
 652         ldlm_namespace_proc_unregister(ns);
 653         ldlm_namespace_cleanup(ns, 0);
 654 out_hash:
 655         cfs_hash_putref(ns->ns_rs_hash);
 656 out_ns:
 657         OBD_FREE_PTR(ns);
 658 out_ref:
 659         ldlm_put_ref();
 660         return NULL;
 661 }
 662 EXPORT_SYMBOL(ldlm_namespace_new);
 663
 664 extern struct ldlm_lock *ldlm_lock_get(struct ldlm_lock *lock);
 665
 666 /**
 667  * Cancel and destroy all locks on a resource.
 668  *
 669  * If flags contains FL_LOCAL_ONLY, don't try to tell the server, just
 670  * clean up.  This is currently only used for recovery, and we make
 671  * certain assumptions as a result--notably, that we shouldn't cancel
 672  * locks with refs.
 673  */
 674 static void cleanup_resource(struct ldlm_resource *res, struct list_head *q,
 675                              __u64 flags)
 676 {
 677         struct list_head *tmp;
 678         int rc = 0, client = ns_is_client(ldlm_res_to_ns(res));
 679         bool local_only = !!(flags & LDLM_FL_LOCAL_ONLY);
 680
 681         do {
 682                 struct ldlm_lock *lock = NULL;
 683
 684                 /* First, we look for non-cleaned-yet lock
 685                  * all cleaned locks are marked by CLEANED flag. */
 686                 lock_res(res);
 687                 list_for_each(tmp, q) {
 688                         lock = list_entry(tmp, struct ldlm_lock,
 689                                               l_res_link);
 690                         if (lock->l_flags & LDLM_FL_CLEANED) {
 691                                 lock = NULL;
 692                                 continue;
 693                         }
 694                         LDLM_LOCK_GET(lock);
 695                         lock->l_flags |= LDLM_FL_CLEANED;
 696                         break;
 697                 }
 698
 699                 if (lock == NULL) {
 700                         unlock_res(res);
 701                         break;
 702                 }
 703
 704                 /* Set CBPENDING so nothing in the cancellation path
 705                  * can match this lock. */
 706                 lock->l_flags |= LDLM_FL_CBPENDING;
 707                 lock->l_flags |= LDLM_FL_FAILED;
 708                 lock->l_flags |= flags;
 709
 710                 /* ... without sending a CANCEL message for local_only. */
 711                 if (local_only)
 712                         lock->l_flags |= LDLM_FL_LOCAL_ONLY;
 713
 714                 if (local_only && (lock->l_readers || lock->l_writers)) {
 715                         /* This is a little bit gross, but much better than the
 716                          * alternative: pretend that we got a blocking AST from
 717                          * the server, so that when the lock is decref'd, it
 718                          * will go away ... */
 719                         unlock_res(res);
 720                         LDLM_DEBUG(lock, "setting FL_LOCAL_ONLY");
 721                         if (lock->l_completion_ast)
 722                                 lock->l_completion_ast(lock, 0, NULL);
 723                         LDLM_LOCK_RELEASE(lock);
 724                         continue;
 725                 }
 726
 727                 if (client) {
 728                         struct lustre_handle lockh;
 729
 730                         unlock_res(res);
 731                         ldlm_lock2handle(lock, &lockh);
 732                         rc = ldlm_cli_cancel(&lockh, LCF_ASYNC);
 733                         if (rc)
 734                                 CERROR("ldlm_cli_cancel: %d\n", rc);
 735                 } else {
 736                         ldlm_resource_unlink_lock(lock);
 737                         unlock_res(res);
 738                         LDLM_DEBUG(lock, "Freeing a lock still held by a "
 739                                    "client node");
 740                         ldlm_lock_destroy(lock);
 741                 }
 742                 LDLM_LOCK_RELEASE(lock);
 743         } while (1);
 744 }
 745
 746 static int ldlm_resource_clean(struct cfs_hash *hs, struct cfs_hash_bd *bd,
 747                                struct hlist_node *hnode, void *arg)
 748 {
 749         struct ldlm_resource *res = cfs_hash_object(hs, hnode);
 750         __u64 flags = *(__u64 *)arg;
 751
 752         cleanup_resource(res, &res->lr_granted, flags);
 753         cleanup_resource(res, &res->lr_converting, flags);
 754         cleanup_resource(res, &res->lr_waiting, flags);
 755
 756         return 0;
 757 }
 758
 759 static int ldlm_resource_complain(struct cfs_hash *hs, struct cfs_hash_bd *bd,
 760                                   struct hlist_node *hnode, void *arg)
 761 {
 762         struct ldlm_resource  *res = cfs_hash_object(hs, hnode);
 763
 764         lock_res(res);
 765         CERROR("%s: namespace resource "DLDLMRES
 766                " (%p) refcount nonzero (%d) after lock cleanup; forcing cleanup.\n",
 767                ldlm_ns_name(ldlm_res_to_ns(res)), PLDLMRES(res), res,
 768                atomic_read(&res->lr_refcount) - 1);
 769
 770         ldlm_resource_dump(D_ERROR, res);
 771         unlock_res(res);
 772         return 0;
 773 }
 774
 775 /**
 776  * Cancel and destroy all locks in the namespace.
 777  *
 778  * Typically used during evictions when server notified client that it was
 779  * evicted and all of its state needs to be destroyed.
 780  * Also used during shutdown.
 781  */
 782 int ldlm_namespace_cleanup(struct ldlm_namespace *ns, __u64 flags)
 783 {
 784         if (ns == NULL) {
 785                 CDEBUG(D_INFO, "NULL ns, skipping cleanup\n");
 786                 return ELDLM_OK;
 787         }
 788
 789         cfs_hash_for_each_nolock(ns->ns_rs_hash, ldlm_resource_clean, &flags);
 790         cfs_hash_for_each_nolock(ns->ns_rs_hash, ldlm_resource_complain, NULL);
 791         return ELDLM_OK;
 792 }
 793 EXPORT_SYMBOL(ldlm_namespace_cleanup);
 794
 795 /**
 796  * Attempts to free namespace.
 797  *
 798  * Only used when namespace goes away, like during an unmount.
 799  */
 800 static int __ldlm_namespace_free(struct ldlm_namespace *ns, int force)
 801 {
 802         /* At shutdown time, don't call the cancellation callback */
 803         ldlm_namespace_cleanup(ns, force ? LDLM_FL_LOCAL_ONLY : 0);
 804
 805         if (atomic_read(&ns->ns_bref) > 0) {
 806                 struct l_wait_info lwi = LWI_INTR(LWI_ON_SIGNAL_NOOP, NULL);
 807                 int rc;
 808                 CDEBUG(D_DLMTRACE,
 809                        "dlm namespace %s free waiting on refcount %d\n",
 810                        ldlm_ns_name(ns), atomic_read(&ns->ns_bref));
 811 force_wait:
 812                 if (force)
 813                         lwi = LWI_TIMEOUT(obd_timeout * HZ / 4, NULL, NULL);
 814
 815                 rc = l_wait_event(ns->ns_waitq,
 816                                   atomic_read(&ns->ns_bref) == 0, &lwi);
 817
 818                 /* Forced cleanups should be able to reclaim all references,
 819                  * so it's safe to wait forever... we can't leak locks... */
 820                 if (force && rc == -ETIMEDOUT) {
 821                         LCONSOLE_ERROR("Forced cleanup waiting for %s "
 822                                        "namespace with %d resources in use, "
 823                                        "(rc=%d)\n", ldlm_ns_name(ns),
 824                                        atomic_read(&ns->ns_bref), rc);
 825                         goto force_wait;
 826                 }
 827
 828                 if (atomic_read(&ns->ns_bref)) {
 829                         LCONSOLE_ERROR("Cleanup waiting for %s namespace "
 830                                        "with %d resources in use, (rc=%d)\n",
 831                                        ldlm_ns_name(ns),
 832                                        atomic_read(&ns->ns_bref), rc);
 833                         return ELDLM_NAMESPACE_EXISTS;
 834                 }
 835                 CDEBUG(D_DLMTRACE, "dlm namespace %s free done waiting\n",
 836                        ldlm_ns_name(ns));
 837         }
 838
 839         return ELDLM_OK;
 840 }
 841
 842 /**
 843  * Performs various cleanups for passed \a ns to make it drop refc and be
 844  * ready for freeing. Waits for refc == 0.
 845  *
 846  * The following is done:
 847  * (0) Unregister \a ns from its list to make inaccessible for potential
 848  * users like pools thread and others;
 849  * (1) Clear all locks in \a ns.
 850  */
 851 void ldlm_namespace_free_prior(struct ldlm_namespace *ns,
 852                                struct obd_import *imp,
 853                                int force)
 854 {
 855         int rc;
 856
 857         if (!ns)
 858                 return;
 859
 860         spin_lock(&ns->ns_lock);
 861         ns->ns_stopping = 1;
 862         spin_unlock(&ns->ns_lock);
 863
 864         /*
 865          * Can fail with -EINTR when force == 0 in which case try harder.
 866          */
 867         rc = __ldlm_namespace_free(ns, force);
 868         if (rc != ELDLM_OK) {
 869                 if (imp) {
 870                         ptlrpc_disconnect_import(imp, 0);
 871                         ptlrpc_invalidate_import(imp);
 872                 }
 873
 874                 /*
 875                  * With all requests dropped and the import inactive
 876                  * we are guaranteed all reference will be dropped.
 877                  */
 878                 rc = __ldlm_namespace_free(ns, 1);
 879                 LASSERT(rc == 0);
 880         }
 881 }
 882
 883 /**
 884  * Performs freeing memory structures related to \a ns. This is only done
 885  * when ldlm_namespce_free_prior() successfully removed all resources
 886  * referencing \a ns and its refc == 0.
 887  */
 888 void ldlm_namespace_free_post(struct ldlm_namespace *ns)
 889 {
 890         if (!ns)
 891                 return;
 892
 893         /* Make sure that nobody can find this ns in its list. */
 894         ldlm_namespace_unregister(ns, ns->ns_client);
 895         /* Fini pool _before_ parent proc dir is removed. This is important as
 896          * ldlm_pool_fini() removes own proc dir which is child to @dir.
 897          * Removing it after @dir may cause oops. */
 898         ldlm_pool_fini(&ns->ns_pool);
 899
 900         ldlm_namespace_proc_unregister(ns);
 901         cfs_hash_putref(ns->ns_rs_hash);
 902         /* Namespace \a ns should be not on list at this time, otherwise
 903          * this will cause issues related to using freed \a ns in poold
 904          * thread. */
 905         LASSERT(list_empty(&ns->ns_list_chain));
 906         OBD_FREE_PTR(ns);
 907         ldlm_put_ref();
 908 }
 909
 910 /**
 911  * Cleanup the resource, and free namespace.
 912  * bug 12864:
 913  * Deadlock issue:
 914  * proc1: destroy import
 915  *      class_disconnect_export(grab cl_sem) ->
 916  *            -> ldlm_namespace_free ->
 917  *            -> lprocfs_remove(grab _lprocfs_lock).
 918  * proc2: read proc info
 919  *      lprocfs_fops_read(grab _lprocfs_lock) ->
 920  *            -> osc_rd_active, etc(grab cl_sem).
 921  *
 922  * So that I have to split the ldlm_namespace_free into two parts - the first
 923  * part ldlm_namespace_free_prior is used to cleanup the resource which is
 924  * being used; the 2nd part ldlm_namespace_free_post is used to unregister the
 925  * lprocfs entries, and then free memory. It will be called w/o cli->cl_sem
 926  * held.
 927  */
 928 void ldlm_namespace_free(struct ldlm_namespace *ns,
 929                          struct obd_import *imp,
 930                          int force)
 931 {
 932         ldlm_namespace_free_prior(ns, imp, force);
 933         ldlm_namespace_free_post(ns);
 934 }
 935 EXPORT_SYMBOL(ldlm_namespace_free);
 936
 937 void ldlm_namespace_get(struct ldlm_namespace *ns)
 938 {
 939         atomic_inc(&ns->ns_bref);
 940 }
 941 EXPORT_SYMBOL(ldlm_namespace_get);
 942
 943 /* This is only for callers that care about refcount */
 944 int ldlm_namespace_get_return(struct ldlm_namespace *ns)
 945 {
 946         return atomic_inc_return(&ns->ns_bref);
 947 }
 948
 949 void ldlm_namespace_put(struct ldlm_namespace *ns)
 950 {
 951         if (atomic_dec_and_lock(&ns->ns_bref, &ns->ns_lock)) {
 952                 wake_up(&ns->ns_waitq);
 953                 spin_unlock(&ns->ns_lock);
 954         }
 955 }
 956 EXPORT_SYMBOL(ldlm_namespace_put);
 957
 958 /** Register \a ns in the list of namespaces */
 959 void ldlm_namespace_register(struct ldlm_namespace *ns, ldlm_side_t client)
 960 {
 961         mutex_lock(ldlm_namespace_lock(client));
 962         LASSERT(list_empty(&ns->ns_list_chain));
 963         list_add(&ns->ns_list_chain, ldlm_namespace_inactive_list(client));
 964         ldlm_namespace_nr_inc(client);
 965         mutex_unlock(ldlm_namespace_lock(client));
 966 }
 967
 968 /** Unregister \a ns from the list of namespaces. */
 969 void ldlm_namespace_unregister(struct ldlm_namespace *ns, ldlm_side_t client)
 970 {
 971         mutex_lock(ldlm_namespace_lock(client));
 972         LASSERT(!list_empty(&ns->ns_list_chain));
 973         /* Some asserts and possibly other parts of the code are still
 974          * using list_empty(&ns->ns_list_chain). This is why it is
 975          * important to use list_del_init() here. */
 976         list_del_init(&ns->ns_list_chain);
 977         ldlm_namespace_nr_dec(client);
 978         mutex_unlock(ldlm_namespace_lock(client));
 979 }
 980
 981 /** Should be called with ldlm_namespace_lock(client) taken. */
 982 void ldlm_namespace_move_to_active_locked(struct ldlm_namespace *ns,
 983                                           ldlm_side_t client)
 984 {
 985         LASSERT(!list_empty(&ns->ns_list_chain));
 986         LASSERT(mutex_is_locked(ldlm_namespace_lock(client)));
 987         list_move_tail(&ns->ns_list_chain, ldlm_namespace_list(client));
 988 }
 989
 990 /** Should be called with ldlm_namespace_lock(client) taken. */
 991 void ldlm_namespace_move_to_inactive_locked(struct ldlm_namespace *ns,
 992                                             ldlm_side_t client)
 993 {
 994         LASSERT(!list_empty(&ns->ns_list_chain));
 995         LASSERT(mutex_is_locked(ldlm_namespace_lock(client)));
 996         list_move_tail(&ns->ns_list_chain,
 997                        ldlm_namespace_inactive_list(client));
 998 }
 999
1000 /** Should be called with ldlm_namespace_lock(client) taken. */
1001 struct ldlm_namespace *ldlm_namespace_first_locked(ldlm_side_t client)
1002 {
1003         LASSERT(mutex_is_locked(ldlm_namespace_lock(client)));
1004         LASSERT(!list_empty(ldlm_namespace_list(client)));
1005         return container_of(ldlm_namespace_list(client)->next,
1006                 struct ldlm_namespace, ns_list_chain);
1007 }
1008
1009 /** Create and initialize new resource. */
1010 static struct ldlm_resource *ldlm_resource_new(void)
1011 {
1012         struct ldlm_resource *res;
1013         int idx;
1014
1015         OBD_SLAB_ALLOC_PTR_GFP(res, ldlm_resource_slab, GFP_NOFS);
1016         if (res == NULL)
1017                 return NULL;
1018
1019         INIT_LIST_HEAD(&res->lr_granted);
1020         INIT_LIST_HEAD(&res->lr_converting);
1021         INIT_LIST_HEAD(&res->lr_waiting);
1022
1023         /* Initialize interval trees for each lock mode. */
1024         for (idx = 0; idx < LCK_MODE_NUM; idx++) {
1025                 res->lr_itree[idx].lit_size = 0;
1026                 res->lr_itree[idx].lit_mode = 1 << idx;
1027                 res->lr_itree[idx].lit_root = NULL;
1028         }
1029
1030         atomic_set(&res->lr_refcount, 1);
1031         spin_lock_init(&res->lr_lock);
1032         lu_ref_init(&res->lr_reference);
1033
1034         /* The creator of the resource must unlock the mutex after LVB
1035          * initialization. */
1036         mutex_init(&res->lr_lvb_mutex);
1037         mutex_lock(&res->lr_lvb_mutex);
1038
1039         return res;
1040 }
1041
1042 /**
1043  * Return a reference to resource with given name, creating it if necessary.
1044  * Args: namespace with ns_lock unlocked
1045  * Locks: takes and releases NS hash-lock and res->lr_lock
1046  * Returns: referenced, unlocked ldlm_resource or NULL
1047  */
1048 struct ldlm_resource *
1049 ldlm_resource_get(struct ldlm_namespace *ns, struct ldlm_resource *parent,
1050                   const struct ldlm_res_id *name, ldlm_type_t type, int create)
1051 {
1052         struct hlist_node     *hnode;
1053         struct ldlm_resource *res;
1054         struct cfs_hash_bd       bd;
1055         __u64            version;
1056         int                   ns_refcount = 0;
1057
1058         LASSERT(ns != NULL);
1059         LASSERT(parent == NULL);
1060         LASSERT(ns->ns_rs_hash != NULL);
1061         LASSERT(name->name[0] != 0);
1062
1063         cfs_hash_bd_get_and_lock(ns->ns_rs_hash, (void *)name, &bd, 0);
1064         hnode = cfs_hash_bd_lookup_locked(ns->ns_rs_hash, &bd, (void *)name);
1065         if (hnode != NULL) {
1066                 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 0);
1067                 res = hlist_entry(hnode, struct ldlm_resource, lr_hash);
1068                 /* Synchronize with regard to resource creation. */
1069                 if (ns->ns_lvbo && ns->ns_lvbo->lvbo_init) {
1070                         mutex_lock(&res->lr_lvb_mutex);
1071                         mutex_unlock(&res->lr_lvb_mutex);
1072                 }
1073
1074                 if (unlikely(res->lr_lvb_len < 0)) {
1075                         ldlm_resource_putref(res);
1076                         res = NULL;
1077                 }
1078                 return res;
1079         }
1080
1081         version = cfs_hash_bd_version_get(&bd);
1082         cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 0);
1083
1084         if (create == 0)
1085                 return NULL;
1086
1087         LASSERTF(type >= LDLM_MIN_TYPE && type < LDLM_MAX_TYPE,
1088                  "type: %d\n", type);
1089         res = ldlm_resource_new();
1090         if (!res)
1091                 return NULL;
1092
1093         res->lr_ns_bucket  = cfs_hash_bd_extra_get(ns->ns_rs_hash, &bd);
1094         res->lr_name       = *name;
1095         res->lr_type       = type;
1096         res->lr_most_restr = LCK_NL;
1097
1098         cfs_hash_bd_lock(ns->ns_rs_hash, &bd, 1);
1099         hnode = (version == cfs_hash_bd_version_get(&bd)) ?  NULL :
1100                 cfs_hash_bd_lookup_locked(ns->ns_rs_hash, &bd, (void *)name);
1101
1102         if (hnode != NULL) {
1103                 /* Someone won the race and already added the resource. */
1104                 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1105                 /* Clean lu_ref for failed resource. */
1106                 lu_ref_fini(&res->lr_reference);
1107                 /* We have taken lr_lvb_mutex. Drop it. */
1108                 mutex_unlock(&res->lr_lvb_mutex);
1109                 OBD_SLAB_FREE(res, ldlm_resource_slab, sizeof(*res));
1110
1111                 res = hlist_entry(hnode, struct ldlm_resource, lr_hash);
1112                 /* Synchronize with regard to resource creation. */
1113                 if (ns->ns_lvbo && ns->ns_lvbo->lvbo_init) {
1114                         mutex_lock(&res->lr_lvb_mutex);
1115                         mutex_unlock(&res->lr_lvb_mutex);
1116                 }
1117
1118                 if (unlikely(res->lr_lvb_len < 0)) {
1119                         ldlm_resource_putref(res);
1120                         res = NULL;
1121                 }
1122                 return res;
1123         }
1124         /* We won! Let's add the resource. */
1125         cfs_hash_bd_add_locked(ns->ns_rs_hash, &bd, &res->lr_hash);
1126         if (cfs_hash_bd_count_get(&bd) == 1)
1127                 ns_refcount = ldlm_namespace_get_return(ns);
1128
1129         cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1130         if (ns->ns_lvbo && ns->ns_lvbo->lvbo_init) {
1131                 int rc;
1132
1133                 OBD_FAIL_TIMEOUT(OBD_FAIL_LDLM_CREATE_RESOURCE, 2);
1134                 rc = ns->ns_lvbo->lvbo_init(res);
1135                 if (rc < 0) {
1136                         CERROR("%s: lvbo_init failed for resource %#llx:%#llx: rc = %d\n",
1137                                ns->ns_obd->obd_name, name->name[0],
1138                                name->name[1], rc);
1139                         if (res->lr_lvb_data) {
1140                                 OBD_FREE(res->lr_lvb_data, res->lr_lvb_len);
1141                                 res->lr_lvb_data = NULL;
1142                         }
1143                         res->lr_lvb_len = rc;
1144                         mutex_unlock(&res->lr_lvb_mutex);
1145                         ldlm_resource_putref(res);
1146                         return NULL;
1147                 }
1148         }
1149
1150         /* We create resource with locked lr_lvb_mutex. */
1151         mutex_unlock(&res->lr_lvb_mutex);
1152
1153         /* Let's see if we happened to be the very first resource in this
1154          * namespace. If so, and this is a client namespace, we need to move
1155          * the namespace into the active namespaces list to be patrolled by
1156          * the ldlm_poold. */
1157         if (ns_is_client(ns) && ns_refcount == 1) {
1158                 mutex_lock(ldlm_namespace_lock(LDLM_NAMESPACE_CLIENT));
1159                 ldlm_namespace_move_to_active_locked(ns, LDLM_NAMESPACE_CLIENT);
1160                 mutex_unlock(ldlm_namespace_lock(LDLM_NAMESPACE_CLIENT));
1161         }
1162
1163         return res;
1164 }
1165 EXPORT_SYMBOL(ldlm_resource_get);
1166
1167 struct ldlm_resource *ldlm_resource_getref(struct ldlm_resource *res)
1168 {
1169         LASSERT(res != NULL);
1170         LASSERT(res != LP_POISON);
1171         atomic_inc(&res->lr_refcount);
1172         CDEBUG(D_INFO, "getref res: %p count: %d\n", res,
1173                atomic_read(&res->lr_refcount));
1174         return res;
1175 }
1176
1177 static void __ldlm_resource_putref_final(struct cfs_hash_bd *bd,
1178                                          struct ldlm_resource *res)
1179 {
1180         struct ldlm_ns_bucket *nsb = res->lr_ns_bucket;
1181
1182         if (!list_empty(&res->lr_granted)) {
1183                 ldlm_resource_dump(D_ERROR, res);
1184                 LBUG();
1185         }
1186
1187         if (!list_empty(&res->lr_converting)) {
1188                 ldlm_resource_dump(D_ERROR, res);
1189                 LBUG();
1190         }
1191
1192         if (!list_empty(&res->lr_waiting)) {
1193                 ldlm_resource_dump(D_ERROR, res);
1194                 LBUG();
1195         }
1196
1197         cfs_hash_bd_del_locked(nsb->nsb_namespace->ns_rs_hash,
1198                                bd, &res->lr_hash);
1199         lu_ref_fini(&res->lr_reference);
1200         if (cfs_hash_bd_count_get(bd) == 0)
1201                 ldlm_namespace_put(nsb->nsb_namespace);
1202 }
1203
1204 /* Returns 1 if the resource was freed, 0 if it remains. */
1205 int ldlm_resource_putref(struct ldlm_resource *res)
1206 {
1207         struct ldlm_namespace *ns = ldlm_res_to_ns(res);
1208         struct cfs_hash_bd   bd;
1209
1210         LASSERT_ATOMIC_GT_LT(&res->lr_refcount, 0, LI_POISON);
1211         CDEBUG(D_INFO, "putref res: %p count: %d\n",
1212                res, atomic_read(&res->lr_refcount) - 1);
1213
1214         cfs_hash_bd_get(ns->ns_rs_hash, &res->lr_name, &bd);
1215         if (cfs_hash_bd_dec_and_lock(ns->ns_rs_hash, &bd, &res->lr_refcount)) {
1216                 __ldlm_resource_putref_final(&bd, res);
1217                 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1218                 if (ns->ns_lvbo && ns->ns_lvbo->lvbo_free)
1219                         ns->ns_lvbo->lvbo_free(res);
1220                 OBD_SLAB_FREE(res, ldlm_resource_slab, sizeof(*res));
1221                 return 1;
1222         }
1223         return 0;
1224 }
1225 EXPORT_SYMBOL(ldlm_resource_putref);
1226
1227 /* Returns 1 if the resource was freed, 0 if it remains. */
1228 int ldlm_resource_putref_locked(struct ldlm_resource *res)
1229 {
1230         struct ldlm_namespace *ns = ldlm_res_to_ns(res);
1231
1232         LASSERT_ATOMIC_GT_LT(&res->lr_refcount, 0, LI_POISON);
1233         CDEBUG(D_INFO, "putref res: %p count: %d\n",
1234                res, atomic_read(&res->lr_refcount) - 1);
1235
1236         if (atomic_dec_and_test(&res->lr_refcount)) {
1237                 struct cfs_hash_bd bd;
1238
1239                 cfs_hash_bd_get(ldlm_res_to_ns(res)->ns_rs_hash,
1240                                 &res->lr_name, &bd);
1241                 __ldlm_resource_putref_final(&bd, res);
1242                 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1243                 /* NB: ns_rs_hash is created with CFS_HASH_NO_ITEMREF,
1244                  * so we should never be here while calling cfs_hash_del,
1245                  * cfs_hash_for_each_nolock is the only case we can get
1246                  * here, which is safe to release cfs_hash_bd_lock.
1247                  */
1248                 if (ns->ns_lvbo && ns->ns_lvbo->lvbo_free)
1249                         ns->ns_lvbo->lvbo_free(res);
1250                 OBD_SLAB_FREE(res, ldlm_resource_slab, sizeof(*res));
1251
1252                 cfs_hash_bd_lock(ns->ns_rs_hash, &bd, 1);
1253                 return 1;
1254         }
1255         return 0;
1256 }
1257
1258 /**
1259  * Add a lock into a given resource into specified lock list.
1260  */
1261 void ldlm_resource_add_lock(struct ldlm_resource *res, struct list_head *head,
1262                             struct ldlm_lock *lock)
1263 {
1264         check_res_locked(res);
1265
1266         LDLM_DEBUG(lock, "About to add this lock:\n");
1267
1268         if (lock->l_flags & LDLM_FL_DESTROYED) {
1269                 CDEBUG(D_OTHER, "Lock destroyed, not adding to resource\n");
1270                 return;
1271         }
1272
1273         LASSERT(list_empty(&lock->l_res_link));
1274
1275         list_add_tail(&lock->l_res_link, head);
1276 }
1277
1278 /**
1279  * Insert a lock into resource after specified lock.
1280  *
1281  * Obtain resource description from the lock we are inserting after.
1282  */
1283 void ldlm_resource_insert_lock_after(struct ldlm_lock *original,
1284                                      struct ldlm_lock *new)
1285 {
1286         struct ldlm_resource *res = original->l_resource;
1287
1288         check_res_locked(res);
1289
1290         ldlm_resource_dump(D_INFO, res);
1291         LDLM_DEBUG(new, "About to insert this lock after %p:\n", original);
1292
1293         if (new->l_flags & LDLM_FL_DESTROYED) {
1294                 CDEBUG(D_OTHER, "Lock destroyed, not adding to resource\n");
1295                 goto out;
1296         }
1297
1298         LASSERT(list_empty(&new->l_res_link));
1299
1300         list_add(&new->l_res_link, &original->l_res_link);
1301  out:;
1302 }
1303
1304 void ldlm_resource_unlink_lock(struct ldlm_lock *lock)
1305 {
1306         int type = lock->l_resource->lr_type;
1307
1308         check_res_locked(lock->l_resource);
1309         if (type == LDLM_IBITS || type == LDLM_PLAIN)
1310                 ldlm_unlink_lock_skiplist(lock);
1311         else if (type == LDLM_EXTENT)
1312                 ldlm_extent_unlink_lock(lock);
1313         list_del_init(&lock->l_res_link);
1314 }
1315 EXPORT_SYMBOL(ldlm_resource_unlink_lock);
1316
1317 void ldlm_res2desc(struct ldlm_resource *res, struct ldlm_resource_desc *desc)
1318 {
1319         desc->lr_type = res->lr_type;
1320         desc->lr_name = res->lr_name;
1321 }
1322
1323 /**
1324  * Print information about all locks in all namespaces on this node to debug
1325  * log.
1326  */
1327 void ldlm_dump_all_namespaces(ldlm_side_t client, int level)
1328 {
1329         struct list_head *tmp;
1330
1331         if (!((libcfs_debug | D_ERROR) & level))
1332                 return;
1333
1334         mutex_lock(ldlm_namespace_lock(client));
1335
1336         list_for_each(tmp, ldlm_namespace_list(client)) {
1337                 struct ldlm_namespace *ns;
1338                 ns = list_entry(tmp, struct ldlm_namespace, ns_list_chain);
1339                 ldlm_namespace_dump(level, ns);
1340         }
1341
1342         mutex_unlock(ldlm_namespace_lock(client));
1343 }
1344 EXPORT_SYMBOL(ldlm_dump_all_namespaces);
1345
1346 static int ldlm_res_hash_dump(struct cfs_hash *hs, struct cfs_hash_bd *bd,
1347                               struct hlist_node *hnode, void *arg)
1348 {
1349         struct ldlm_resource *res = cfs_hash_object(hs, hnode);
1350         int    level = (int)(unsigned long)arg;
1351
1352         lock_res(res);
1353         ldlm_resource_dump(level, res);
1354         unlock_res(res);
1355
1356         return 0;
1357 }
1358
1359 /**
1360  * Print information about all locks in this namespace on this node to debug
1361  * log.
1362  */
1363 void ldlm_namespace_dump(int level, struct ldlm_namespace *ns)
1364 {
1365         if (!((libcfs_debug | D_ERROR) & level))
1366                 return;
1367
1368         CDEBUG(level, "--- Namespace: %s (rc: %d, side: %s)\n",
1369                ldlm_ns_name(ns), atomic_read(&ns->ns_bref),
1370                ns_is_client(ns) ? "client" : "server");
1371
1372         if (time_before(cfs_time_current(), ns->ns_next_dump))
1373                 return;
1374
1375         cfs_hash_for_each_nolock(ns->ns_rs_hash,
1376                                  ldlm_res_hash_dump,
1377                                  (void *)(unsigned long)level);
1378         spin_lock(&ns->ns_lock);
1379         ns->ns_next_dump = cfs_time_shift(10);
1380         spin_unlock(&ns->ns_lock);
1381 }
1382 EXPORT_SYMBOL(ldlm_namespace_dump);
1383
1384 /**
1385  * Print information about all locks in this resource to debug log.
1386  */
1387 void ldlm_resource_dump(int level, struct ldlm_resource *res)
1388 {
1389         struct ldlm_lock *lock;
1390         unsigned int granted = 0;
1391
1392         CLASSERT(RES_NAME_SIZE == 4);
1393
1394         if (!((libcfs_debug | D_ERROR) & level))
1395                 return;
1396
1397         CDEBUG(level, "--- Resource: "DLDLMRES" (%p) refcount = %d\n",
1398                PLDLMRES(res), res, atomic_read(&res->lr_refcount));
1399
1400         if (!list_empty(&res->lr_granted)) {
1401                 CDEBUG(level, "Granted locks (in reverse order):\n");
1402                 list_for_each_entry_reverse(lock, &res->lr_granted,
1403                                                 l_res_link) {
1404                         LDLM_DEBUG_LIMIT(level, lock, "###");
1405                         if (!(level & D_CANTMASK) &&
1406                             ++granted > ldlm_dump_granted_max) {
1407                                 CDEBUG(level, "only dump %d granted locks to "
1408                                        "avoid DDOS.\n", granted);
1409                                 break;
1410                         }
1411                 }
1412         }
1413         if (!list_empty(&res->lr_converting)) {
1414                 CDEBUG(level, "Converting locks:\n");
1415                 list_for_each_entry(lock, &res->lr_converting, l_res_link)
1416                         LDLM_DEBUG_LIMIT(level, lock, "###");
1417         }
1418         if (!list_empty(&res->lr_waiting)) {
1419                 CDEBUG(level, "Waiting locks:\n");
1420                 list_for_each_entry(lock, &res->lr_waiting, l_res_link)
1421                         LDLM_DEBUG_LIMIT(level, lock, "###");
1422         }
1423 }