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