Pileus Git - ~andy/linux/blob - 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 <lustre_dlm.h>
  44
  45 #include <lustre_fid.h>
  46 #include <obd_class.h>
  47 #include "ldlm_internal.h"
  48
  49 struct kmem_cache *ldlm_resource_slab, *ldlm_lock_slab;
  50
  51 int ldlm_srv_namespace_nr = 0;
  52 int ldlm_cli_namespace_nr = 0;
  53
  54 struct mutex ldlm_srv_namespace_lock;
  55 LIST_HEAD(ldlm_srv_namespace_list);
  56
  57 struct mutex ldlm_cli_namespace_lock;
  58 /* Client Namespaces that have active resources in them.
  59  * Once all resources go away, ldlm_poold moves such namespaces to the
  60  * inactive list */
  61 LIST_HEAD(ldlm_cli_active_namespace_list);
  62 /* Client namespaces that don't have any locks in them */
  63 LIST_HEAD(ldlm_cli_inactive_namespace_list);
  64
  65 struct proc_dir_entry *ldlm_type_proc_dir = NULL;
  66 struct proc_dir_entry *ldlm_ns_proc_dir = NULL;
  67 struct proc_dir_entry *ldlm_svc_proc_dir = NULL;
  68
  69 extern unsigned int ldlm_cancel_unused_locks_before_replay;
  70
  71 /* during debug dump certain amount of granted locks for one resource to avoid
  72  * DDOS. */
  73 unsigned int ldlm_dump_granted_max = 256;
  74
  75 #ifdef LPROCFS
  76 static ssize_t lprocfs_wr_dump_ns(struct file *file, const char *buffer,
  77                                   size_t count, loff_t *off)
  78 {
  79         ldlm_dump_all_namespaces(LDLM_NAMESPACE_SERVER, D_DLMTRACE);
  80         ldlm_dump_all_namespaces(LDLM_NAMESPACE_CLIENT, D_DLMTRACE);
  81         return count;
  82 }
  83 LPROC_SEQ_FOPS_WR_ONLY(ldlm, dump_ns);
  84
  85 LPROC_SEQ_FOPS_RW_TYPE(ldlm_rw, uint);
  86 LPROC_SEQ_FOPS_RO_TYPE(ldlm, uint);
  87
  88 int ldlm_proc_setup(void)
  89 {
  90         int rc;
  91         struct lprocfs_vars list[] = {
  92                 { "dump_namespaces", &ldlm_dump_ns_fops, 0, 0222 },
  93                 { "dump_granted_max", &ldlm_rw_uint_fops,
  94                   &ldlm_dump_granted_max },
  95                 { "cancel_unused_locks_before_replay", &ldlm_rw_uint_fops,
  96                   &ldlm_cancel_unused_locks_before_replay },
  97                 { NULL }};
  98         LASSERT(ldlm_ns_proc_dir == NULL);
  99
 100         ldlm_type_proc_dir = lprocfs_register(OBD_LDLM_DEVICENAME,
 101                                               proc_lustre_root,
 102                                               NULL, NULL);
 103         if (IS_ERR(ldlm_type_proc_dir)) {
 104                 CERROR("LProcFS failed in ldlm-init\n");
 105                 rc = PTR_ERR(ldlm_type_proc_dir);
 106                 GOTO(err, rc);
 107         }
 108
 109         ldlm_ns_proc_dir = lprocfs_register("namespaces",
 110                                             ldlm_type_proc_dir,
 111                                             NULL, NULL);
 112         if (IS_ERR(ldlm_ns_proc_dir)) {
 113                 CERROR("LProcFS failed in ldlm-init\n");
 114                 rc = PTR_ERR(ldlm_ns_proc_dir);
 115                 GOTO(err_type, rc);
 116         }
 117
 118         ldlm_svc_proc_dir = lprocfs_register("services",
 119                                             ldlm_type_proc_dir,
 120                                             NULL, NULL);
 121         if (IS_ERR(ldlm_svc_proc_dir)) {
 122                 CERROR("LProcFS failed in ldlm-init\n");
 123                 rc = PTR_ERR(ldlm_svc_proc_dir);
 124                 GOTO(err_ns, rc);
 125         }
 126
 127         rc = lprocfs_add_vars(ldlm_type_proc_dir, list, NULL);
 128
 129         return 0;
 130
 131 err_ns:
 132         lprocfs_remove(&ldlm_ns_proc_dir);
 133 err_type:
 134         lprocfs_remove(&ldlm_type_proc_dir);
 135 err:
 136         ldlm_svc_proc_dir = NULL;
 137         ldlm_type_proc_dir = NULL;
 138         ldlm_ns_proc_dir = NULL;
 139         return rc;
 140 }
 141
 142 void ldlm_proc_cleanup(void)
 143 {
 144         if (ldlm_svc_proc_dir)
 145                 lprocfs_remove(&ldlm_svc_proc_dir);
 146
 147         if (ldlm_ns_proc_dir)
 148                 lprocfs_remove(&ldlm_ns_proc_dir);
 149
 150         if (ldlm_type_proc_dir)
 151                 lprocfs_remove(&ldlm_type_proc_dir);
 152
 153         ldlm_svc_proc_dir = NULL;
 154         ldlm_type_proc_dir = NULL;
 155         ldlm_ns_proc_dir = NULL;
 156 }
 157
 158 static int lprocfs_ns_resources_seq_show(struct seq_file *m, void *v)
 159 {
 160         struct ldlm_namespace *ns  = m->private;
 161         __u64             res = 0;
 162         struct cfs_hash_bd        bd;
 163         int                 i;
 164
 165         /* result is not strictly consistent */
 166         cfs_hash_for_each_bucket(ns->ns_rs_hash, &bd, i)
 167                 res += cfs_hash_bd_count_get(&bd);
 168         return lprocfs_rd_u64(m, &res);
 169 }
 170 LPROC_SEQ_FOPS_RO(lprocfs_ns_resources);
 171
 172 static int lprocfs_ns_locks_seq_show(struct seq_file *m, void *v)
 173 {
 174         struct ldlm_namespace *ns = m->private;
 175         __u64             locks;
 176
 177         locks = lprocfs_stats_collector(ns->ns_stats, LDLM_NSS_LOCKS,
 178                                         LPROCFS_FIELDS_FLAGS_SUM);
 179         return lprocfs_rd_u64(m, &locks);
 180 }
 181 LPROC_SEQ_FOPS_RO(lprocfs_ns_locks);
 182
 183 static int lprocfs_lru_size_seq_show(struct seq_file *m, void *v)
 184 {
 185         struct ldlm_namespace *ns = m->private;
 186         __u32 *nr = &ns->ns_max_unused;
 187
 188         if (ns_connect_lru_resize(ns))
 189                 nr = &ns->ns_nr_unused;
 190         return lprocfs_rd_uint(m, nr);
 191 }
 192
 193 static ssize_t lprocfs_lru_size_seq_write(struct file *file, const char *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], *end;
 198         unsigned long tmp;
 199         int lru_resize;
 200
 201         dummy[MAX_STRING_SIZE] = '\0';
 202         if (copy_from_user(dummy, buffer, MAX_STRING_SIZE))
 203                 return -EFAULT;
 204
 205         if (strncmp(dummy, "clear", 5) == 0) {
 206                 CDEBUG(D_DLMTRACE,
 207                        "dropping all unused locks from namespace %s\n",
 208                        ldlm_ns_name(ns));
 209                 if (ns_connect_lru_resize(ns)) {
 210                         int canceled, unused  = ns->ns_nr_unused;
 211
 212                         /* Try to cancel all @ns_nr_unused locks. */
 213                         canceled = ldlm_cancel_lru(ns, unused, 0,
 214                                                    LDLM_CANCEL_PASSED);
 215                         if (canceled < unused) {
 216                                 CDEBUG(D_DLMTRACE,
 217                                        "not all requested locks are canceled, "
 218                                        "requested: %d, canceled: %d\n", unused,
 219                                        canceled);
 220                                 return -EINVAL;
 221                         }
 222                 } else {
 223                         tmp = ns->ns_max_unused;
 224                         ns->ns_max_unused = 0;
 225                         ldlm_cancel_lru(ns, 0, 0, LDLM_CANCEL_PASSED);
 226                         ns->ns_max_unused = tmp;
 227                 }
 228                 return count;
 229         }
 230
 231         tmp = simple_strtoul(dummy, &end, 0);
 232         if (dummy == end) {
 233                 CERROR("invalid value written\n");
 234                 return -EINVAL;
 235         }
 236         lru_resize = (tmp == 0);
 237
 238         if (ns_connect_lru_resize(ns)) {
 239                 if (!lru_resize)
 240                         ns->ns_max_unused = (unsigned int)tmp;
 241
 242                 if (tmp > ns->ns_nr_unused)
 243                         tmp = ns->ns_nr_unused;
 244                 tmp = ns->ns_nr_unused - tmp;
 245
 246                 CDEBUG(D_DLMTRACE,
 247                        "changing namespace %s unused locks from %u to %u\n",
 248                        ldlm_ns_name(ns), ns->ns_nr_unused,
 249                        (unsigned int)tmp);
 250                 ldlm_cancel_lru(ns, tmp, LCF_ASYNC, LDLM_CANCEL_PASSED);
 251
 252                 if (!lru_resize) {
 253                         CDEBUG(D_DLMTRACE,
 254                                "disable lru_resize for namespace %s\n",
 255                                ldlm_ns_name(ns));
 256                         ns->ns_connect_flags &= ~OBD_CONNECT_LRU_RESIZE;
 257                 }
 258         } else {
 259                 CDEBUG(D_DLMTRACE,
 260                        "changing namespace %s max_unused from %u to %u\n",
 261                        ldlm_ns_name(ns), ns->ns_max_unused,
 262                        (unsigned int)tmp);
 263                 ns->ns_max_unused = (unsigned int)tmp;
 264                 ldlm_cancel_lru(ns, 0, LCF_ASYNC, LDLM_CANCEL_PASSED);
 265
 266                 /* Make sure that LRU resize was originally supported before
 267                  * turning it on here. */
 268                 if (lru_resize &&
 269                     (ns->ns_orig_connect_flags & OBD_CONNECT_LRU_RESIZE)) {
 270                         CDEBUG(D_DLMTRACE,
 271                                "enable lru_resize for namespace %s\n",
 272                                ldlm_ns_name(ns));
 273                         ns->ns_connect_flags |= OBD_CONNECT_LRU_RESIZE;
 274                 }
 275         }
 276
 277         return count;
 278 }
 279 LPROC_SEQ_FOPS(lprocfs_lru_size);
 280
 281 static int lprocfs_elc_seq_show(struct seq_file *m, void *v)
 282 {
 283         struct ldlm_namespace *ns = m->private;
 284         unsigned int supp = ns_connect_cancelset(ns);
 285
 286         return lprocfs_rd_uint(m, &supp);
 287 }
 288
 289 static ssize_t lprocfs_elc_seq_write(struct file *file, const char *buffer,
 290                                  size_t count, loff_t *off)
 291 {
 292         struct ldlm_namespace *ns = ((struct seq_file *)file->private_data)->private;
 293         unsigned int supp = -1;
 294         int rc;
 295
 296         rc = lprocfs_wr_uint(file, buffer, count, &supp);
 297         if (rc < 0)
 298                 return rc;
 299
 300         if (supp == 0)
 301                 ns->ns_connect_flags &= ~OBD_CONNECT_CANCELSET;
 302         else if (ns->ns_orig_connect_flags & OBD_CONNECT_CANCELSET)
 303                 ns->ns_connect_flags |= OBD_CONNECT_CANCELSET;
 304         return count;
 305 }
 306 LPROC_SEQ_FOPS(lprocfs_elc);
 307
 308 void ldlm_namespace_proc_unregister(struct ldlm_namespace *ns)
 309 {
 310         if (ns->ns_proc_dir_entry == NULL)
 311                 CERROR("dlm namespace %s has no procfs dir?\n",
 312                        ldlm_ns_name(ns));
 313         else
 314                 lprocfs_remove(&ns->ns_proc_dir_entry);
 315
 316         if (ns->ns_stats != NULL)
 317                 lprocfs_free_stats(&ns->ns_stats);
 318 }
 319
 320 #define LDLM_NS_ADD_VAR(name, var, ops)                         \
 321         do {                                                    \
 322                 snprintf(lock_name, MAX_STRING_SIZE, name);     \
 323                 lock_vars[0].data = var;                        \
 324                 lock_vars[0].fops = ops;                        \
 325                 lprocfs_add_vars(ns_pde, lock_vars, 0);         \
 326         } while (0)
 327
 328 int ldlm_namespace_proc_register(struct ldlm_namespace *ns)
 329 {
 330         struct lprocfs_vars lock_vars[2];
 331         char lock_name[MAX_STRING_SIZE + 1];
 332         struct proc_dir_entry *ns_pde;
 333
 334         LASSERT(ns != NULL);
 335         LASSERT(ns->ns_rs_hash != NULL);
 336
 337         if (ns->ns_proc_dir_entry != NULL) {
 338                 ns_pde = ns->ns_proc_dir_entry;
 339         } else {
 340                 ns_pde = proc_mkdir(ldlm_ns_name(ns), ldlm_ns_proc_dir);
 341                 if (ns_pde == NULL)
 342                         return -ENOMEM;
 343                 ns->ns_proc_dir_entry = ns_pde;
 344         }
 345
 346         ns->ns_stats = lprocfs_alloc_stats(LDLM_NSS_LAST, 0);
 347         if (ns->ns_stats == NULL)
 348                 return -ENOMEM;
 349
 350         lprocfs_counter_init(ns->ns_stats, LDLM_NSS_LOCKS,
 351                              LPROCFS_CNTR_AVGMINMAX, "locks", "locks");
 352
 353         lock_name[MAX_STRING_SIZE] = '\0';
 354
 355         memset(lock_vars, 0, sizeof(lock_vars));
 356         lock_vars[0].name = lock_name;
 357
 358         LDLM_NS_ADD_VAR("resource_count", ns, &lprocfs_ns_resources_fops);
 359         LDLM_NS_ADD_VAR("lock_count", ns, &lprocfs_ns_locks_fops);
 360
 361         if (ns_is_client(ns)) {
 362                 LDLM_NS_ADD_VAR("lock_unused_count", &ns->ns_nr_unused,
 363                                 &ldlm_uint_fops);
 364                 LDLM_NS_ADD_VAR("lru_size", ns, &lprocfs_lru_size_fops);
 365                 LDLM_NS_ADD_VAR("lru_max_age", &ns->ns_max_age,
 366                                 &ldlm_rw_uint_fops);
 367                 LDLM_NS_ADD_VAR("early_lock_cancel", ns, &lprocfs_elc_fops);
 368         } else {
 369                 LDLM_NS_ADD_VAR("ctime_age_limit", &ns->ns_ctime_age_limit,
 370                                 &ldlm_rw_uint_fops);
 371                 LDLM_NS_ADD_VAR("lock_timeouts", &ns->ns_timeouts,
 372                                 &ldlm_uint_fops);
 373                 LDLM_NS_ADD_VAR("max_nolock_bytes", &ns->ns_max_nolock_size,
 374                                 &ldlm_rw_uint_fops);
 375                 LDLM_NS_ADD_VAR("contention_seconds", &ns->ns_contention_time,
 376                                 &ldlm_rw_uint_fops);
 377                 LDLM_NS_ADD_VAR("contended_locks", &ns->ns_contended_locks,
 378                                 &ldlm_rw_uint_fops);
 379                 LDLM_NS_ADD_VAR("max_parallel_ast", &ns->ns_max_parallel_ast,
 380                                 &ldlm_rw_uint_fops);
 381         }
 382         return 0;
 383 }
 384 #undef MAX_STRING_SIZE
 385 #else /* LPROCFS */
 386
 387 #define ldlm_namespace_proc_unregister(ns)      ({;})
 388 #define ldlm_namespace_proc_register(ns)        ({0;})
 389
 390 #endif /* LPROCFS */
 391
 392 static unsigned ldlm_res_hop_hash(struct cfs_hash *hs,
 393                                   const void *key, unsigned mask)
 394 {
 395         const struct ldlm_res_id     *id  = key;
 396         unsigned                val = 0;
 397         unsigned                i;
 398
 399         for (i = 0; i < RES_NAME_SIZE; i++)
 400                 val += id->name[i];
 401         return val & mask;
 402 }
 403
 404 static unsigned ldlm_res_hop_fid_hash(struct cfs_hash *hs,
 405                                       const void *key, unsigned mask)
 406 {
 407         const struct ldlm_res_id *id = key;
 408         struct lu_fid       fid;
 409         __u32          hash;
 410         __u32          val;
 411
 412         fid.f_seq = id->name[LUSTRE_RES_ID_SEQ_OFF];
 413         fid.f_oid = (__u32)id->name[LUSTRE_RES_ID_VER_OID_OFF];
 414         fid.f_ver = (__u32)(id->name[LUSTRE_RES_ID_VER_OID_OFF] >> 32);
 415
 416         hash = fid_flatten32(&fid);
 417         hash += (hash >> 4) + (hash << 12); /* mixing oid and seq */
 418         if (id->name[LUSTRE_RES_ID_HSH_OFF] != 0) {
 419                 val = id->name[LUSTRE_RES_ID_HSH_OFF];
 420                 hash += (val >> 5) + (val << 11);
 421         } else {
 422                 val = fid_oid(&fid);
 423         }
 424         hash = cfs_hash_long(hash, hs->hs_bkt_bits);
 425         /* give me another random factor */
 426         hash -= cfs_hash_long((unsigned long)hs, val % 11 + 3);
 427
 428         hash <<= hs->hs_cur_bits - hs->hs_bkt_bits;
 429         hash |= ldlm_res_hop_hash(hs, key, CFS_HASH_NBKT(hs) - 1);
 430
 431         return hash & mask;
 432 }
 433
 434 static void *ldlm_res_hop_key(struct hlist_node *hnode)
 435 {
 436         struct ldlm_resource   *res;
 437
 438         res = hlist_entry(hnode, struct ldlm_resource, lr_hash);
 439         return &res->lr_name;
 440 }
 441
 442 static int ldlm_res_hop_keycmp(const void *key, struct hlist_node *hnode)
 443 {
 444         struct ldlm_resource   *res;
 445
 446         res = hlist_entry(hnode, struct ldlm_resource, lr_hash);
 447         return ldlm_res_eq((const struct ldlm_res_id *)key,
 448                            (const struct ldlm_res_id *)&res->lr_name);
 449 }
 450
 451 static void *ldlm_res_hop_object(struct hlist_node *hnode)
 452 {
 453         return hlist_entry(hnode, struct ldlm_resource, lr_hash);
 454 }
 455
 456 static void ldlm_res_hop_get_locked(struct cfs_hash *hs, struct hlist_node *hnode)
 457 {
 458         struct ldlm_resource *res;
 459
 460         res = hlist_entry(hnode, struct ldlm_resource, lr_hash);
 461         ldlm_resource_getref(res);
 462 }
 463
 464 static void ldlm_res_hop_put_locked(struct cfs_hash *hs, struct hlist_node *hnode)
 465 {
 466         struct ldlm_resource *res;
 467
 468         res = hlist_entry(hnode, struct ldlm_resource, lr_hash);
 469         /* cfs_hash_for_each_nolock is the only chance we call it */
 470         ldlm_resource_putref_locked(res);
 471 }
 472
 473 static void ldlm_res_hop_put(struct cfs_hash *hs, struct hlist_node *hnode)
 474 {
 475         struct ldlm_resource *res;
 476
 477         res = hlist_entry(hnode, struct ldlm_resource, lr_hash);
 478         ldlm_resource_putref(res);
 479 }
 480
 481 cfs_hash_ops_t ldlm_ns_hash_ops = {
 482         .hs_hash        = ldlm_res_hop_hash,
 483         .hs_key  = ldlm_res_hop_key,
 484         .hs_keycmp      = ldlm_res_hop_keycmp,
 485         .hs_keycpy      = NULL,
 486         .hs_object      = ldlm_res_hop_object,
 487         .hs_get  = ldlm_res_hop_get_locked,
 488         .hs_put_locked  = ldlm_res_hop_put_locked,
 489         .hs_put  = ldlm_res_hop_put
 490 };
 491
 492 cfs_hash_ops_t ldlm_ns_fid_hash_ops = {
 493         .hs_hash        = ldlm_res_hop_fid_hash,
 494         .hs_key  = ldlm_res_hop_key,
 495         .hs_keycmp      = ldlm_res_hop_keycmp,
 496         .hs_keycpy      = NULL,
 497         .hs_object      = ldlm_res_hop_object,
 498         .hs_get  = ldlm_res_hop_get_locked,
 499         .hs_put_locked  = ldlm_res_hop_put_locked,
 500         .hs_put  = ldlm_res_hop_put
 501 };
 502
 503 typedef struct {
 504         ldlm_ns_type_t  nsd_type;
 505         /** hash bucket bits */
 506         unsigned        nsd_bkt_bits;
 507         /** hash bits */
 508         unsigned        nsd_all_bits;
 509         /** hash operations */
 510         cfs_hash_ops_t *nsd_hops;
 511 } ldlm_ns_hash_def_t;
 512
 513 ldlm_ns_hash_def_t ldlm_ns_hash_defs[] =
 514 {
 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         ldlm_ns_hash_def_t    *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, NULL);
 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, NULL);
 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, NULL);
 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, rc);
 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, rc);
 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, rc);
 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
 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
 895         /* Make sure that nobody can find this ns in its list. */
 896         ldlm_namespace_unregister(ns, ns->ns_client);
 897         /* Fini pool _before_ parent proc dir is removed. This is important as
 898          * ldlm_pool_fini() removes own proc dir which is child to @dir.
 899          * Removing it after @dir may cause oops. */
 900         ldlm_pool_fini(&ns->ns_pool);
 901
 902         ldlm_namespace_proc_unregister(ns);
 903         cfs_hash_putref(ns->ns_rs_hash);
 904         /* Namespace \a ns should be not on list at this time, otherwise
 905          * this will cause issues related to using freed \a ns in poold
 906          * thread. */
 907         LASSERT(list_empty(&ns->ns_list_chain));
 908         OBD_FREE_PTR(ns);
 909         ldlm_put_ref();
 910 }
 911
 912 /**
 913  * Cleanup the resource, and free namespace.
 914  * bug 12864:
 915  * Deadlock issue:
 916  * proc1: destroy import
 917  *      class_disconnect_export(grab cl_sem) ->
 918  *            -> ldlm_namespace_free ->
 919  *            -> lprocfs_remove(grab _lprocfs_lock).
 920  * proc2: read proc info
 921  *      lprocfs_fops_read(grab _lprocfs_lock) ->
 922  *            -> osc_rd_active, etc(grab cl_sem).
 923  *
 924  * So that I have to split the ldlm_namespace_free into two parts - the first
 925  * part ldlm_namespace_free_prior is used to cleanup the resource which is
 926  * being used; the 2nd part ldlm_namespace_free_post is used to unregister the
 927  * lprocfs entries, and then free memory. It will be called w/o cli->cl_sem
 928  * held.
 929  */
 930 void ldlm_namespace_free(struct ldlm_namespace *ns,
 931                          struct obd_import *imp,
 932                          int force)
 933 {
 934         ldlm_namespace_free_prior(ns, imp, force);
 935         ldlm_namespace_free_post(ns);
 936 }
 937 EXPORT_SYMBOL(ldlm_namespace_free);
 938
 939 void ldlm_namespace_get(struct ldlm_namespace *ns)
 940 {
 941         atomic_inc(&ns->ns_bref);
 942 }
 943 EXPORT_SYMBOL(ldlm_namespace_get);
 944
 945 /* This is only for callers that care about refcount */
 946 int ldlm_namespace_get_return(struct ldlm_namespace *ns)
 947 {
 948         return atomic_inc_return(&ns->ns_bref);
 949 }
 950
 951 void ldlm_namespace_put(struct ldlm_namespace *ns)
 952 {
 953         if (atomic_dec_and_lock(&ns->ns_bref, &ns->ns_lock)) {
 954                 wake_up(&ns->ns_waitq);
 955                 spin_unlock(&ns->ns_lock);
 956         }
 957 }
 958 EXPORT_SYMBOL(ldlm_namespace_put);
 959
 960 /** Register \a ns in the list of namespaces */
 961 void ldlm_namespace_register(struct ldlm_namespace *ns, ldlm_side_t client)
 962 {
 963         mutex_lock(ldlm_namespace_lock(client));
 964         LASSERT(list_empty(&ns->ns_list_chain));
 965         list_add(&ns->ns_list_chain, ldlm_namespace_inactive_list(client));
 966         ldlm_namespace_nr_inc(client);
 967         mutex_unlock(ldlm_namespace_lock(client));
 968 }
 969
 970 /** Unregister \a ns from the list of namespaces. */
 971 void ldlm_namespace_unregister(struct ldlm_namespace *ns, ldlm_side_t client)
 972 {
 973         mutex_lock(ldlm_namespace_lock(client));
 974         LASSERT(!list_empty(&ns->ns_list_chain));
 975         /* Some asserts and possibly other parts of the code are still
 976          * using list_empty(&ns->ns_list_chain). This is why it is
 977          * important to use list_del_init() here. */
 978         list_del_init(&ns->ns_list_chain);
 979         ldlm_namespace_nr_dec(client);
 980         mutex_unlock(ldlm_namespace_lock(client));
 981 }
 982
 983 /** Should be called with ldlm_namespace_lock(client) taken. */
 984 void ldlm_namespace_move_to_active_locked(struct ldlm_namespace *ns,
 985                                           ldlm_side_t client)
 986 {
 987         LASSERT(!list_empty(&ns->ns_list_chain));
 988         LASSERT(mutex_is_locked(ldlm_namespace_lock(client)));
 989         list_move_tail(&ns->ns_list_chain, ldlm_namespace_list(client));
 990 }
 991
 992 /** Should be called with ldlm_namespace_lock(client) taken. */
 993 void ldlm_namespace_move_to_inactive_locked(struct ldlm_namespace *ns,
 994                                             ldlm_side_t client)
 995 {
 996         LASSERT(!list_empty(&ns->ns_list_chain));
 997         LASSERT(mutex_is_locked(ldlm_namespace_lock(client)));
 998         list_move_tail(&ns->ns_list_chain,
 999                        ldlm_namespace_inactive_list(client));
1000 }
1001
1002 /** Should be called with ldlm_namespace_lock(client) taken. */
1003 struct ldlm_namespace *ldlm_namespace_first_locked(ldlm_side_t client)
1004 {
1005         LASSERT(mutex_is_locked(ldlm_namespace_lock(client)));
1006         LASSERT(!list_empty(ldlm_namespace_list(client)));
1007         return container_of(ldlm_namespace_list(client)->next,
1008                 struct ldlm_namespace, ns_list_chain);
1009 }
1010
1011 /** Create and initialize new resource. */
1012 static struct ldlm_resource *ldlm_resource_new(void)
1013 {
1014         struct ldlm_resource *res;
1015         int idx;
1016
1017         OBD_SLAB_ALLOC_PTR_GFP(res, ldlm_resource_slab, __GFP_IO);
1018         if (res == NULL)
1019                 return NULL;
1020
1021         INIT_LIST_HEAD(&res->lr_granted);
1022         INIT_LIST_HEAD(&res->lr_converting);
1023         INIT_LIST_HEAD(&res->lr_waiting);
1024
1025         /* Initialize interval trees for each lock mode. */
1026         for (idx = 0; idx < LCK_MODE_NUM; idx++) {
1027                 res->lr_itree[idx].lit_size = 0;
1028                 res->lr_itree[idx].lit_mode = 1 << idx;
1029                 res->lr_itree[idx].lit_root = NULL;
1030         }
1031
1032         atomic_set(&res->lr_refcount, 1);
1033         spin_lock_init(&res->lr_lock);
1034         lu_ref_init(&res->lr_reference);
1035
1036         /* The creator of the resource must unlock the mutex after LVB
1037          * initialization. */
1038         mutex_init(&res->lr_lvb_mutex);
1039         mutex_lock(&res->lr_lvb_mutex);
1040
1041         return res;
1042 }
1043
1044 /**
1045  * Return a reference to resource with given name, creating it if necessary.
1046  * Args: namespace with ns_lock unlocked
1047  * Locks: takes and releases NS hash-lock and res->lr_lock
1048  * Returns: referenced, unlocked ldlm_resource or NULL
1049  */
1050 struct ldlm_resource *
1051 ldlm_resource_get(struct ldlm_namespace *ns, struct ldlm_resource *parent,
1052                   const struct ldlm_res_id *name, ldlm_type_t type, int create)
1053 {
1054         struct hlist_node     *hnode;
1055         struct ldlm_resource *res;
1056         struct cfs_hash_bd       bd;
1057         __u64            version;
1058         int                   ns_refcount = 0;
1059
1060         LASSERT(ns != NULL);
1061         LASSERT(parent == NULL);
1062         LASSERT(ns->ns_rs_hash != NULL);
1063         LASSERT(name->name[0] != 0);
1064
1065         cfs_hash_bd_get_and_lock(ns->ns_rs_hash, (void *)name, &bd, 0);
1066         hnode = cfs_hash_bd_lookup_locked(ns->ns_rs_hash, &bd, (void *)name);
1067         if (hnode != NULL) {
1068                 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 0);
1069                 res = hlist_entry(hnode, struct ldlm_resource, lr_hash);
1070                 /* Synchronize with regard to resource creation. */
1071                 if (ns->ns_lvbo && ns->ns_lvbo->lvbo_init) {
1072                         mutex_lock(&res->lr_lvb_mutex);
1073                         mutex_unlock(&res->lr_lvb_mutex);
1074                 }
1075
1076                 if (unlikely(res->lr_lvb_len < 0)) {
1077                         ldlm_resource_putref(res);
1078                         res = NULL;
1079                 }
1080                 return res;
1081         }
1082
1083         version = cfs_hash_bd_version_get(&bd);
1084         cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 0);
1085
1086         if (create == 0)
1087                 return NULL;
1088
1089         LASSERTF(type >= LDLM_MIN_TYPE && type < LDLM_MAX_TYPE,
1090                  "type: %d\n", type);
1091         res = ldlm_resource_new();
1092         if (!res)
1093                 return NULL;
1094
1095         res->lr_ns_bucket  = cfs_hash_bd_extra_get(ns->ns_rs_hash, &bd);
1096         res->lr_name       = *name;
1097         res->lr_type       = type;
1098         res->lr_most_restr = LCK_NL;
1099
1100         cfs_hash_bd_lock(ns->ns_rs_hash, &bd, 1);
1101         hnode = (version == cfs_hash_bd_version_get(&bd)) ?  NULL :
1102                 cfs_hash_bd_lookup_locked(ns->ns_rs_hash, &bd, (void *)name);
1103
1104         if (hnode != NULL) {
1105                 /* Someone won the race and already added the resource. */
1106                 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1107                 /* Clean lu_ref for failed resource. */
1108                 lu_ref_fini(&res->lr_reference);
1109                 /* We have taken lr_lvb_mutex. Drop it. */
1110                 mutex_unlock(&res->lr_lvb_mutex);
1111                 OBD_SLAB_FREE(res, ldlm_resource_slab, sizeof(*res));
1112
1113                 res = hlist_entry(hnode, struct ldlm_resource, lr_hash);
1114                 /* Synchronize with regard to resource creation. */
1115                 if (ns->ns_lvbo && ns->ns_lvbo->lvbo_init) {
1116                         mutex_lock(&res->lr_lvb_mutex);
1117                         mutex_unlock(&res->lr_lvb_mutex);
1118                 }
1119
1120                 if (unlikely(res->lr_lvb_len < 0)) {
1121                         ldlm_resource_putref(res);
1122                         res = NULL;
1123                 }
1124                 return res;
1125         }
1126         /* We won! Let's add the resource. */
1127         cfs_hash_bd_add_locked(ns->ns_rs_hash, &bd, &res->lr_hash);
1128         if (cfs_hash_bd_count_get(&bd) == 1)
1129                 ns_refcount = ldlm_namespace_get_return(ns);
1130
1131         cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1132         if (ns->ns_lvbo && ns->ns_lvbo->lvbo_init) {
1133                 int rc;
1134
1135                 OBD_FAIL_TIMEOUT(OBD_FAIL_LDLM_CREATE_RESOURCE, 2);
1136                 rc = ns->ns_lvbo->lvbo_init(res);
1137                 if (rc < 0) {
1138                         CERROR("%s: lvbo_init failed for resource "LPX64":"
1139                                LPX64": rc = %d\n", ns->ns_obd->obd_name,
1140                                name->name[0], name->name[1], rc);
1141                         if (res->lr_lvb_data) {
1142                                 OBD_FREE(res->lr_lvb_data, res->lr_lvb_len);
1143                                 res->lr_lvb_data = NULL;
1144                         }
1145                         res->lr_lvb_len = rc;
1146                         mutex_unlock(&res->lr_lvb_mutex);
1147                         ldlm_resource_putref(res);
1148                         return NULL;
1149                 }
1150         }
1151
1152         /* We create resource with locked lr_lvb_mutex. */
1153         mutex_unlock(&res->lr_lvb_mutex);
1154
1155         /* Let's see if we happened to be the very first resource in this
1156          * namespace. If so, and this is a client namespace, we need to move
1157          * the namespace into the active namespaces list to be patrolled by
1158          * the ldlm_poold. */
1159         if (ns_is_client(ns) && ns_refcount == 1) {
1160                 mutex_lock(ldlm_namespace_lock(LDLM_NAMESPACE_CLIENT));
1161                 ldlm_namespace_move_to_active_locked(ns, LDLM_NAMESPACE_CLIENT);
1162                 mutex_unlock(ldlm_namespace_lock(LDLM_NAMESPACE_CLIENT));
1163         }
1164
1165         return res;
1166 }
1167 EXPORT_SYMBOL(ldlm_resource_get);
1168
1169 struct ldlm_resource *ldlm_resource_getref(struct ldlm_resource *res)
1170 {
1171         LASSERT(res != NULL);
1172         LASSERT(res != LP_POISON);
1173         atomic_inc(&res->lr_refcount);
1174         CDEBUG(D_INFO, "getref res: %p count: %d\n", res,
1175                atomic_read(&res->lr_refcount));
1176         return res;
1177 }
1178
1179 static void __ldlm_resource_putref_final(struct cfs_hash_bd *bd,
1180                                          struct ldlm_resource *res)
1181 {
1182         struct ldlm_ns_bucket *nsb = res->lr_ns_bucket;
1183
1184         if (!list_empty(&res->lr_granted)) {
1185                 ldlm_resource_dump(D_ERROR, res);
1186                 LBUG();
1187         }
1188
1189         if (!list_empty(&res->lr_converting)) {
1190                 ldlm_resource_dump(D_ERROR, res);
1191                 LBUG();
1192         }
1193
1194         if (!list_empty(&res->lr_waiting)) {
1195                 ldlm_resource_dump(D_ERROR, res);
1196                 LBUG();
1197         }
1198
1199         cfs_hash_bd_del_locked(nsb->nsb_namespace->ns_rs_hash,
1200                                bd, &res->lr_hash);
1201         lu_ref_fini(&res->lr_reference);
1202         if (cfs_hash_bd_count_get(bd) == 0)
1203                 ldlm_namespace_put(nsb->nsb_namespace);
1204 }
1205
1206 /* Returns 1 if the resource was freed, 0 if it remains. */
1207 int ldlm_resource_putref(struct ldlm_resource *res)
1208 {
1209         struct ldlm_namespace *ns = ldlm_res_to_ns(res);
1210         struct cfs_hash_bd   bd;
1211
1212         LASSERT_ATOMIC_GT_LT(&res->lr_refcount, 0, LI_POISON);
1213         CDEBUG(D_INFO, "putref res: %p count: %d\n",
1214                res, atomic_read(&res->lr_refcount) - 1);
1215
1216         cfs_hash_bd_get(ns->ns_rs_hash, &res->lr_name, &bd);
1217         if (cfs_hash_bd_dec_and_lock(ns->ns_rs_hash, &bd, &res->lr_refcount)) {
1218                 __ldlm_resource_putref_final(&bd, res);
1219                 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1220                 if (ns->ns_lvbo && ns->ns_lvbo->lvbo_free)
1221                         ns->ns_lvbo->lvbo_free(res);
1222                 OBD_SLAB_FREE(res, ldlm_resource_slab, sizeof(*res));
1223                 return 1;
1224         }
1225         return 0;
1226 }
1227 EXPORT_SYMBOL(ldlm_resource_putref);
1228
1229 /* Returns 1 if the resource was freed, 0 if it remains. */
1230 int ldlm_resource_putref_locked(struct ldlm_resource *res)
1231 {
1232         struct ldlm_namespace *ns = ldlm_res_to_ns(res);
1233
1234         LASSERT_ATOMIC_GT_LT(&res->lr_refcount, 0, LI_POISON);
1235         CDEBUG(D_INFO, "putref res: %p count: %d\n",
1236                res, atomic_read(&res->lr_refcount) - 1);
1237
1238         if (atomic_dec_and_test(&res->lr_refcount)) {
1239                 struct cfs_hash_bd bd;
1240
1241                 cfs_hash_bd_get(ldlm_res_to_ns(res)->ns_rs_hash,
1242                                 &res->lr_name, &bd);
1243                 __ldlm_resource_putref_final(&bd, res);
1244                 cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
1245                 /* NB: ns_rs_hash is created with CFS_HASH_NO_ITEMREF,
1246                  * so we should never be here while calling cfs_hash_del,
1247                  * cfs_hash_for_each_nolock is the only case we can get
1248                  * here, which is safe to release cfs_hash_bd_lock.
1249                  */
1250                 if (ns->ns_lvbo && ns->ns_lvbo->lvbo_free)
1251                         ns->ns_lvbo->lvbo_free(res);
1252                 OBD_SLAB_FREE(res, ldlm_resource_slab, sizeof(*res));
1253
1254                 cfs_hash_bd_lock(ns->ns_rs_hash, &bd, 1);
1255                 return 1;
1256         }
1257         return 0;
1258 }
1259
1260 /**
1261  * Add a lock into a given resource into specified lock list.
1262  */
1263 void ldlm_resource_add_lock(struct ldlm_resource *res, struct list_head *head,
1264                             struct ldlm_lock *lock)
1265 {
1266         check_res_locked(res);
1267
1268         LDLM_DEBUG(lock, "About to add this lock:\n");
1269
1270         if (lock->l_flags & LDLM_FL_DESTROYED) {
1271                 CDEBUG(D_OTHER, "Lock destroyed, not adding to resource\n");
1272                 return;
1273         }
1274
1275         LASSERT(list_empty(&lock->l_res_link));
1276
1277         list_add_tail(&lock->l_res_link, head);
1278 }
1279
1280 /**
1281  * Insert a lock into resource after specified lock.
1282  *
1283  * Obtain resource description from the lock we are inserting after.
1284  */
1285 void ldlm_resource_insert_lock_after(struct ldlm_lock *original,
1286                                      struct ldlm_lock *new)
1287 {
1288         struct ldlm_resource *res = original->l_resource;
1289
1290         check_res_locked(res);
1291
1292         ldlm_resource_dump(D_INFO, res);
1293         LDLM_DEBUG(new, "About to insert this lock after %p:\n", original);
1294
1295         if (new->l_flags & LDLM_FL_DESTROYED) {
1296                 CDEBUG(D_OTHER, "Lock destroyed, not adding to resource\n");
1297                 goto out;
1298         }
1299
1300         LASSERT(list_empty(&new->l_res_link));
1301
1302         list_add(&new->l_res_link, &original->l_res_link);
1303  out:;
1304 }
1305
1306 void ldlm_resource_unlink_lock(struct ldlm_lock *lock)
1307 {
1308         int type = lock->l_resource->lr_type;
1309
1310         check_res_locked(lock->l_resource);
1311         if (type == LDLM_IBITS || type == LDLM_PLAIN)
1312                 ldlm_unlink_lock_skiplist(lock);
1313         else if (type == LDLM_EXTENT)
1314                 ldlm_extent_unlink_lock(lock);
1315         list_del_init(&lock->l_res_link);
1316 }
1317 EXPORT_SYMBOL(ldlm_resource_unlink_lock);
1318
1319 void ldlm_res2desc(struct ldlm_resource *res, struct ldlm_resource_desc *desc)
1320 {
1321         desc->lr_type = res->lr_type;
1322         desc->lr_name = res->lr_name;
1323 }
1324
1325 /**
1326  * Print information about all locks in all namespaces on this node to debug
1327  * log.
1328  */
1329 void ldlm_dump_all_namespaces(ldlm_side_t client, int level)
1330 {
1331         struct list_head *tmp;
1332
1333         if (!((libcfs_debug | D_ERROR) & level))
1334                 return;
1335
1336         mutex_lock(ldlm_namespace_lock(client));
1337
1338         list_for_each(tmp, ldlm_namespace_list(client)) {
1339                 struct ldlm_namespace *ns;
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 (cfs_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 "
1410                                        "avoid DDOS.\n", 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 }