lustre/ldlm/ldlm_resource.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  * Copyright (C) 2002, 2003 Cluster File Systems, Inc.
   5  *   Author: Phil Schwan <phil@clusterfs.com>
   6  *   Author: Peter Braam <braam@clusterfs.com>
   7  *
   8  *   This file is part of Lustre, http://www.lustre.org.
   9  *
  10  *   Lustre is free software; you can redistribute it and/or
  11  *   modify it under the terms of version 2 of the GNU General Public
  12  *   License as published by the Free Software Foundation.
  13  *
  14  *   Lustre is distributed in the hope that it will be useful,
  15  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  *   GNU General Public License for more details.
  18  *
  19  *   You should have received a copy of the GNU General Public License
  20  *   along with Lustre; if not, write to the Free Software
  21  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22  */
  23
  24 #define DEBUG_SUBSYSTEM S_LDLM
  25 #ifdef __KERNEL__
  26 # include <linux/lustre_dlm.h>
  27 #else
  28 # include <liblustre.h>
  29 #endif
  30
  31 #include <linux/obd_class.h>
  32 #include "ldlm_internal.h"
  33
  34 kmem_cache_t *ldlm_resource_slab, *ldlm_lock_slab;
  35
  36 DECLARE_MUTEX(ldlm_namespace_lock);
  37 struct list_head ldlm_namespace_list = LIST_HEAD_INIT(ldlm_namespace_list);
  38 struct proc_dir_entry *ldlm_type_proc_dir = NULL;
  39 struct proc_dir_entry *ldlm_ns_proc_dir = NULL;
  40 struct proc_dir_entry *ldlm_svc_proc_dir = NULL;
  41
  42 #ifdef __KERNEL__
  43 static int ldlm_proc_dump_ns(struct file *file, const char *buffer,
  44                              unsigned long count, void *data)
  45 {
  46         ldlm_dump_all_namespaces(D_DLMTRACE);
  47         RETURN(count);
  48 }
  49
  50 int ldlm_proc_setup(void)
  51 {
  52         int rc;
  53         struct lprocfs_vars list[] = {
  54                 { "dump_namespaces", NULL, ldlm_proc_dump_ns, NULL },
  55                 { NULL }};
  56         ENTRY;
  57         LASSERT(ldlm_ns_proc_dir == NULL);
  58
  59         ldlm_type_proc_dir = lprocfs_register(OBD_LDLM_DEVICENAME,
  60                                               proc_lustre_root,
  61                                               NULL, NULL);
  62         if (IS_ERR(ldlm_type_proc_dir)) {
  63                 CERROR("LProcFS failed in ldlm-init\n");
  64                 rc = PTR_ERR(ldlm_type_proc_dir);
  65                 GOTO(err, rc);
  66         }
  67
  68         ldlm_ns_proc_dir = lprocfs_register("namespaces",
  69                                             ldlm_type_proc_dir,
  70                                             NULL, NULL);
  71         if (IS_ERR(ldlm_ns_proc_dir)) {
  72                 CERROR("LProcFS failed in ldlm-init\n");
  73                 rc = PTR_ERR(ldlm_ns_proc_dir);
  74                 GOTO(err_type, rc);
  75         }
  76
  77         ldlm_svc_proc_dir = lprocfs_register("services",
  78                                             ldlm_type_proc_dir,
  79                                             NULL, NULL);
  80         if (IS_ERR(ldlm_svc_proc_dir)) {
  81                 CERROR("LProcFS failed in ldlm-init\n");
  82                 rc = PTR_ERR(ldlm_svc_proc_dir);
  83                 GOTO(err_ns, rc);
  84         }
  85
  86         rc = lprocfs_add_vars(ldlm_type_proc_dir, list, NULL);
  87
  88         RETURN(0);
  89
  90 err_ns:
  91         lprocfs_remove(ldlm_ns_proc_dir);
  92 err_type:
  93         lprocfs_remove(ldlm_type_proc_dir);
  94 err:
  95         ldlm_type_proc_dir = NULL;
  96         ldlm_ns_proc_dir = NULL;
  97         ldlm_svc_proc_dir = NULL;
  98         RETURN(rc);
  99 }
 100
 101 void ldlm_proc_cleanup(void)
 102 {
 103         if (ldlm_svc_proc_dir) {
 104                 lprocfs_remove(ldlm_svc_proc_dir);
 105                 ldlm_svc_proc_dir = NULL;
 106         }
 107
 108         if (ldlm_ns_proc_dir) {
 109                 lprocfs_remove(ldlm_ns_proc_dir);
 110                 ldlm_ns_proc_dir = NULL;
 111         }
 112
 113         if (ldlm_type_proc_dir) {
 114                 lprocfs_remove(ldlm_type_proc_dir);
 115                 ldlm_type_proc_dir = NULL;
 116         }
 117 }
 118
 119 static int lprocfs_uint_rd(char *page, char **start, off_t off,
 120                            int count, int *eof, void *data)
 121 {
 122         unsigned int *temp = (unsigned int *)data;
 123         return snprintf(page, count, "%u\n", *temp);
 124 }
 125
 126 static int lprocfs_read_lru_size(char *page, char **start, off_t off,
 127                                  int count, int *eof, void *data)
 128 {
 129         struct ldlm_namespace *ns = data;
 130         return lprocfs_uint_rd(page, start, off, count, eof,
 131                                &ns->ns_max_unused);
 132 }
 133
 134 #define MAX_STRING_SIZE 128
 135 static int lprocfs_write_lru_size(struct file *file, const char *buffer,
 136                                   unsigned long count, void *data)
 137 {
 138         struct ldlm_namespace *ns = data;
 139         char dummy[MAX_STRING_SIZE + 1], *end;
 140         unsigned long tmp;
 141
 142         dummy[MAX_STRING_SIZE] = '\0';
 143         if (copy_from_user(dummy, buffer, MAX_STRING_SIZE))
 144                 return -EFAULT;
 145
 146         if (count == 6 && memcmp(dummy, "clear", 5) == 0) {
 147                 CDEBUG(D_DLMTRACE,
 148                        "dropping all unused locks from namespace %s\n",
 149                        ns->ns_name);
 150                 tmp = ns->ns_max_unused;
 151                 ns->ns_max_unused = 0;
 152                 ldlm_cancel_lru(ns, LDLM_SYNC);
 153                 ns->ns_max_unused = tmp;
 154                 return count;
 155         }
 156
 157         tmp = simple_strtoul(dummy, &end, 0);
 158         if (tmp == 0 && *end) {
 159                 CERROR("invalid value written\n");
 160                 return -EINVAL;
 161         }
 162
 163         CDEBUG(D_DLMTRACE, "changing namespace %s max_unused from %u to %u\n",
 164                ns->ns_name, ns->ns_max_unused, (unsigned int)tmp);
 165
 166         ns->ns_max_unused = (unsigned int)tmp;
 167         ldlm_cancel_lru(ns, LDLM_ASYNC);
 168         return count;
 169 }
 170
 171 void ldlm_proc_namespace(struct ldlm_namespace *ns)
 172 {
 173         struct lprocfs_vars lock_vars[2];
 174         char lock_name[MAX_STRING_SIZE + 1];
 175
 176         LASSERT(ns != NULL);
 177         LASSERT(ns->ns_name != NULL);
 178
 179         lock_name[MAX_STRING_SIZE] = '\0';
 180
 181         memset(lock_vars, 0, sizeof(lock_vars));
 182         lock_vars[0].read_fptr = lprocfs_rd_u64;
 183         lock_vars[0].name = lock_name;
 184
 185         snprintf(lock_name, MAX_STRING_SIZE, "%s/resource_count", ns->ns_name);
 186         lock_vars[0].data = &ns->ns_resources;
 187         lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
 188
 189         snprintf(lock_name, MAX_STRING_SIZE, "%s/lock_count", ns->ns_name);
 190         lock_vars[0].data = &ns->ns_locks;
 191         lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
 192
 193         if (ns->ns_client) {
 194                 snprintf(lock_name, MAX_STRING_SIZE, "%s/lock_unused_count",
 195                          ns->ns_name);
 196                 lock_vars[0].data = &ns->ns_nr_unused;
 197                 lock_vars[0].read_fptr = lprocfs_uint_rd;
 198                 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
 199
 200                 snprintf(lock_name, MAX_STRING_SIZE, "%s/lru_size",
 201                          ns->ns_name);
 202                 lock_vars[0].data = ns;
 203                 lock_vars[0].read_fptr = lprocfs_read_lru_size;
 204                 lock_vars[0].write_fptr = lprocfs_write_lru_size;
 205                 lprocfs_add_vars(ldlm_ns_proc_dir, lock_vars, 0);
 206         }
 207 }
 208 #endif
 209 #undef MAX_STRING_SIZE
 210
 211 struct ldlm_namespace *ldlm_namespace_new(char *name, __u32 client)
 212 {
 213         struct ldlm_namespace *ns = NULL;
 214         struct list_head *bucket;
 215         int rc;
 216         ENTRY;
 217
 218         rc = ldlm_get_ref();
 219         if (rc) {
 220                 CERROR("ldlm_get_ref failed: %d\n", rc);
 221                 RETURN(NULL);
 222         }
 223
 224         OBD_ALLOC(ns, sizeof(*ns));
 225         if (!ns)
 226                 GOTO(out_ref, NULL);
 227
 228         OBD_VMALLOC(ns->ns_hash, sizeof(*ns->ns_hash) * RES_HASH_SIZE);
 229         if (!ns->ns_hash)
 230                 GOTO(out_ns, NULL);
 231
 232         OBD_ALLOC(ns->ns_name, strlen(name) + 1);
 233         if (!ns->ns_name)
 234                 GOTO(out_hash, NULL);
 235
 236         strcpy(ns->ns_name, name);
 237
 238         INIT_LIST_HEAD(&ns->ns_root_list);
 239         ns->ns_refcount = 0;
 240         ns->ns_client = client;
 241         spin_lock_init(&ns->ns_hash_lock);
 242         atomic_set(&ns->ns_locks, 0);
 243         ns->ns_resources = 0;
 244         init_waitqueue_head(&ns->ns_waitq);
 245
 246         for (bucket = ns->ns_hash + RES_HASH_SIZE - 1; bucket >= ns->ns_hash;
 247              bucket--)
 248                 INIT_LIST_HEAD(bucket);
 249
 250         INIT_LIST_HEAD(&ns->ns_unused_list);
 251         ns->ns_nr_unused = 0;
 252         ns->ns_max_unused = LDLM_DEFAULT_LRU_SIZE;
 253         spin_lock_init(&ns->ns_unused_lock);
 254
 255         down(&ldlm_namespace_lock);
 256         list_add(&ns->ns_list_chain, &ldlm_namespace_list);
 257         up(&ldlm_namespace_lock);
 258 #ifdef __KERNEL__
 259         ldlm_proc_namespace(ns);
 260 #endif
 261         RETURN(ns);
 262
 263 out_hash:
 264         POISON(ns->ns_hash, 0x5a, sizeof(*ns->ns_hash) * RES_HASH_SIZE);
 265         OBD_VFREE(ns->ns_hash, sizeof(*ns->ns_hash) * RES_HASH_SIZE);
 266 out_ns:
 267         OBD_FREE(ns, sizeof(*ns));
 268 out_ref:
 269         ldlm_put_ref(0);
 270         RETURN(NULL);
 271 }
 272
 273 extern struct ldlm_lock *ldlm_lock_get(struct ldlm_lock *lock);
 274
 275 /* If flags contains FL_LOCAL_ONLY, don't try to tell the server, just cleanup.
 276  * This is currently only used for recovery, and we make certain assumptions
 277  * as a result--notably, that we shouldn't cancel locks with refs. -phil
 278  *
 279  * Called with the ns_lock held. */
 280 static void cleanup_resource(struct ldlm_resource *res, struct list_head *q,
 281                              int flags)
 282 {
 283         struct list_head *tmp;
 284         int rc = 0, client = res->lr_namespace->ns_client;
 285         int local_only = (flags & LDLM_FL_LOCAL_ONLY);
 286         ENTRY;
 287
 288
 289         do {
 290                 struct ldlm_lock *lock = NULL;
 291
 292                 /* first, we look for non-cleaned-yet lock
 293                  * all cleaned locks are marked by CLEANED flag */
 294                 lock_res(res);
 295                 list_for_each(tmp, q) {
 296                         lock = list_entry(tmp, struct ldlm_lock, l_res_link);
 297                         if (lock->l_flags & LDLM_FL_CLEANED) {
 298                                 lock = NULL;
 299                                 continue;
 300                         }
 301                         LDLM_LOCK_GET(lock);
 302                         lock->l_flags |= LDLM_FL_CLEANED;
 303                         break;
 304                 }
 305
 306                 if (lock == NULL) {
 307                         unlock_res(res);
 308                         break;
 309                 }
 310
 311                 /* Set CBPENDING so nothing in the cancellation path
 312                  * can match this lock */
 313                 lock->l_flags |= LDLM_FL_CBPENDING;
 314                 lock->l_flags |= LDLM_FL_FAILED;
 315                 lock->l_flags |= flags;
 316
 317                 if (local_only && (lock->l_readers || lock->l_writers)) {
 318                         /* This is a little bit gross, but much better than the
 319                          * alternative: pretend that we got a blocking AST from
 320                          * the server, so that when the lock is decref'd, it
 321                          * will go away ... */
 322                         /* ... without sending a CANCEL message. */
 323                         lock->l_flags |= LDLM_FL_LOCAL_ONLY;
 324                         unlock_res(res);
 325                         LDLM_DEBUG(lock, "setting FL_LOCAL_ONLY");
 326                         if (lock->l_completion_ast)
 327                                 lock->l_completion_ast(lock, 0, NULL);
 328                         LDLM_LOCK_PUT(lock);
 329                         continue;
 330                 }
 331
 332                 if (client) {
 333                         struct lustre_handle lockh;
 334
 335                         unlock_res(res);
 336                         ldlm_lock2handle(lock, &lockh);
 337                         if (!local_only) {
 338                                 rc = ldlm_cli_cancel(&lockh);
 339                                 if (rc)
 340                                         CERROR("ldlm_cli_cancel: %d\n", rc);
 341                         }
 342                         /* Force local cleanup on errors, too. */
 343                         if (local_only || rc != ELDLM_OK)
 344                                 ldlm_lock_cancel(lock);
 345                 } else {
 346                         ldlm_resource_unlink_lock(lock);
 347                         unlock_res(res);
 348                         LDLM_DEBUG(lock, "Freeing a lock still held by a "
 349                                    "client node");
 350                         ldlm_lock_destroy(lock);
 351                 }
 352                 LDLM_LOCK_PUT(lock);
 353         } while (1);
 354
 355         EXIT;
 356 }
 357
 358 int ldlm_namespace_cleanup(struct ldlm_namespace *ns, int flags)
 359 {
 360         struct list_head *tmp;
 361         int i;
 362
 363         if (ns == NULL) {
 364                 CDEBUG(D_INFO, "NULL ns, skipping cleanup\n");
 365                 return ELDLM_OK;
 366         }
 367
 368         for (i = 0; i < RES_HASH_SIZE; i++) {
 369                 spin_lock(&ns->ns_hash_lock);
 370                 tmp = ns->ns_hash[i].next;
 371                 while (tmp != &(ns->ns_hash[i])) {
 372                         struct ldlm_resource *res;
 373                         res = list_entry(tmp, struct ldlm_resource, lr_hash);
 374                         spin_unlock(&ns->ns_hash_lock);
 375                         ldlm_resource_getref(res);
 376                         spin_unlock(&ns->ns_hash_lock);
 377
 378                         cleanup_resource(res, &res->lr_granted, flags);
 379                         cleanup_resource(res, &res->lr_converting, flags);
 380                         cleanup_resource(res, &res->lr_waiting, flags);
 381
 382                         spin_lock(&ns->ns_hash_lock);
 383                         tmp  = tmp->next;
 384
 385                         /* XXX what a mess: don't force cleanup if we're
 386                          * local_only (which is only used by recovery).  In that
 387                          * case, we probably still have outstanding lock refs
 388                          * which reference these resources. -phil */
 389                         if (!ldlm_resource_putref_locked(res) &&
 390                             !(flags & LDLM_FL_LOCAL_ONLY)) {
 391                                 CERROR("Resource refcount nonzero (%d) after "
 392                                        "lock cleanup; forcing cleanup.\n",
 393                                        atomic_read(&res->lr_refcount));
 394                                 ldlm_resource_dump(D_ERROR, res);
 395                                 atomic_set(&res->lr_refcount, 1);
 396                                 ldlm_resource_putref_locked(res);
 397                         }
 398                 }
 399                 spin_unlock(&ns->ns_hash_lock);
 400         }
 401
 402         return ELDLM_OK;
 403 }
 404
 405 /* Cleanup, but also free, the namespace */
 406 int ldlm_namespace_free(struct ldlm_namespace *ns, int force)
 407 {
 408         if (!ns)
 409                 RETURN(ELDLM_OK);
 410
 411         down(&ldlm_namespace_lock);
 412         list_del(&ns->ns_list_chain);
 413         up(&ldlm_namespace_lock);
 414
 415         /* At shutdown time, don't call the cancellation callback */
 416         ldlm_namespace_cleanup(ns, 0);
 417
 418 #ifdef __KERNEL__
 419         {
 420                 struct proc_dir_entry *dir;
 421                 dir = lprocfs_srch(ldlm_ns_proc_dir, ns->ns_name);
 422                 if (dir == NULL) {
 423                         CERROR("dlm namespace %s has no procfs dir?\n",
 424                                ns->ns_name);
 425                 } else {
 426                         lprocfs_remove(dir);
 427                 }
 428         }
 429 #endif
 430
 431         POISON(ns->ns_hash, 0x5a, sizeof(*ns->ns_hash) * RES_HASH_SIZE);
 432         OBD_VFREE(ns->ns_hash, sizeof(*ns->ns_hash) * RES_HASH_SIZE);
 433         OBD_FREE(ns->ns_name, strlen(ns->ns_name) + 1);
 434         OBD_FREE(ns, sizeof(*ns));
 435
 436         ldlm_put_ref(force);
 437
 438         return ELDLM_OK;
 439 }
 440
 441 static __u32 ldlm_hash_fn(struct ldlm_resource *parent, struct ldlm_res_id name)
 442 {
 443         __u32 hash = 0;
 444         int i;
 445
 446         for (i = 0; i < RES_NAME_SIZE; i++)
 447                 hash += name.name[i];
 448
 449         hash += (__u32)((unsigned long)parent >> 4);
 450
 451         return (hash & RES_HASH_MASK);
 452 }
 453
 454 static struct ldlm_resource *ldlm_resource_new(void)
 455 {
 456         struct ldlm_resource *res;
 457
 458         OBD_SLAB_ALLOC(res, ldlm_resource_slab, SLAB_NOFS, sizeof *res);
 459         if (res == NULL)
 460                 return NULL;
 461
 462         memset(res, 0, sizeof(*res));
 463
 464         INIT_LIST_HEAD(&res->lr_children);
 465         INIT_LIST_HEAD(&res->lr_childof);
 466         INIT_LIST_HEAD(&res->lr_granted);
 467         INIT_LIST_HEAD(&res->lr_converting);
 468         INIT_LIST_HEAD(&res->lr_waiting);
 469         atomic_set(&res->lr_refcount, 1);
 470         spin_lock_init(&res->lr_lock);
 471
 472         /* one who creates the resource must unlock
 473          * the semaphore after lvb initialization */
 474         init_MUTEX_LOCKED(&res->lr_lvb_sem);
 475
 476         return res;
 477 }
 478
 479 /* must be called with hash lock held */
 480 static struct ldlm_resource *
 481 ldlm_resource_find(struct ldlm_namespace *ns, struct ldlm_res_id name, __u32 hash)
 482 {
 483         struct list_head *bucket, *tmp;
 484         struct ldlm_resource *res;
 485
 486         LASSERT_SPIN_LOCKED(&ns->ns_hash_lock);
 487         bucket = ns->ns_hash + hash;
 488
 489         list_for_each(tmp, bucket) {
 490                 res = list_entry(tmp, struct ldlm_resource, lr_hash);
 491                 if (memcmp(&res->lr_name, &name, sizeof(res->lr_name)) == 0)
 492                         return res;
 493         }
 494
 495         return NULL;
 496 }
 497
 498 /* Args: locked namespace
 499  * Returns: newly-allocated, referenced, unlocked resource */
 500 static struct ldlm_resource *
 501 ldlm_resource_add(struct ldlm_namespace *ns, struct ldlm_resource *parent,
 502                   struct ldlm_res_id name, __u32 hash, __u32 type)
 503 {
 504         struct list_head *bucket;
 505         struct ldlm_resource *res, *old_res;
 506         ENTRY;
 507
 508         LASSERTF(type >= LDLM_MIN_TYPE && type <= LDLM_MAX_TYPE,
 509                  "type: %d", type);
 510
 511         res = ldlm_resource_new();
 512         if (!res)
 513                 RETURN(NULL);
 514
 515         memcpy(&res->lr_name, &name, sizeof(res->lr_name));
 516         res->lr_namespace = ns;
 517         res->lr_type = type;
 518         res->lr_most_restr = LCK_NL;
 519
 520         spin_lock(&ns->ns_hash_lock);
 521         old_res = ldlm_resource_find(ns, name, hash);
 522         if (old_res) {
 523                 /* someone won the race and added the resource before */
 524                 ldlm_resource_getref(old_res);
 525                 spin_unlock(&ns->ns_hash_lock);
 526                 OBD_SLAB_FREE(res, ldlm_resource_slab, sizeof *res);
 527                 /* synchronize WRT resource creation */
 528                 if (ns->ns_lvbo && ns->ns_lvbo->lvbo_init) {
 529                         down(&old_res->lr_lvb_sem);
 530                         up(&old_res->lr_lvb_sem);
 531                 }
 532                 RETURN(old_res);
 533         }
 534
 535         /* we won! let's add the resource */
 536         bucket = ns->ns_hash + hash;
 537         list_add(&res->lr_hash, bucket);
 538         ns->ns_resources++;
 539         ns->ns_refcount++;
 540
 541         if (parent == NULL) {
 542                 list_add(&res->lr_childof, &ns->ns_root_list);
 543         } else {
 544                 res->lr_parent = parent;
 545                 list_add(&res->lr_childof, &parent->lr_children);
 546         }
 547         spin_unlock(&ns->ns_hash_lock);
 548
 549         if (ns->ns_lvbo && ns->ns_lvbo->lvbo_init) {
 550                 int rc;
 551
 552                 OBD_FAIL_TIMEOUT(OBD_FAIL_LDLM_CREATE_RESOURCE, 2);
 553                 rc = ns->ns_lvbo->lvbo_init(res);
 554                 if (rc)
 555                         CERROR("lvbo_init failed for resource "
 556                                LPU64": rc %d\n", name.name[0], rc);
 557                 /* we create resource with locked lr_lvb_sem */
 558                 up(&res->lr_lvb_sem);
 559         }
 560
 561         RETURN(res);
 562 }
 563
 564 /* Args: unlocked namespace
 565  * Locks: takes and releases ns->ns_lock and res->lr_lock
 566  * Returns: referenced, unlocked ldlm_resource or NULL */
 567 struct ldlm_resource *
 568 ldlm_resource_get(struct ldlm_namespace *ns, struct ldlm_resource *parent,
 569                   struct ldlm_res_id name, __u32 type, int create)
 570 {
 571         __u32 hash = ldlm_hash_fn(parent, name);
 572         struct ldlm_resource *res = NULL;
 573         ENTRY;
 574
 575         LASSERT(ns != NULL);
 576         LASSERT(ns->ns_hash != NULL);
 577         LASSERT(name.name[0] != 0);
 578
 579         spin_lock(&ns->ns_hash_lock);
 580         res = ldlm_resource_find(ns, name, hash);
 581         if (res) {
 582                 ldlm_resource_getref(res);
 583                 spin_unlock(&ns->ns_hash_lock);
 584                 /* synchronize WRT resource creation */
 585                 if (ns->ns_lvbo && ns->ns_lvbo->lvbo_init) {
 586                         down(&res->lr_lvb_sem);
 587                         up(&res->lr_lvb_sem);
 588                 }
 589                 RETURN(res);
 590         }
 591         spin_unlock(&ns->ns_hash_lock);
 592
 593         if (create == 0)
 594                 RETURN(NULL);
 595
 596         res = ldlm_resource_add(ns, parent, name, hash, type);
 597         RETURN(res);
 598 }
 599
 600 struct ldlm_resource *ldlm_resource_getref(struct ldlm_resource *res)
 601 {
 602         LASSERT(res != NULL);
 603         LASSERT(res != LP_POISON);
 604         atomic_inc(&res->lr_refcount);
 605         CDEBUG(D_INFO, "getref res: %p count: %d\n", res,
 606                atomic_read(&res->lr_refcount));
 607         return res;
 608 }
 609
 610 void __ldlm_resource_putref_final(struct ldlm_resource *res)
 611 {
 612         struct ldlm_namespace *ns = res->lr_namespace;
 613
 614         LASSERT_SPIN_LOCKED(&ns->ns_hash_lock);
 615
 616         if (!list_empty(&res->lr_granted)) {
 617                 ldlm_resource_dump(D_ERROR, res);
 618                 LBUG();
 619         }
 620
 621         if (!list_empty(&res->lr_converting)) {
 622                 ldlm_resource_dump(D_ERROR, res);
 623                 LBUG();
 624         }
 625
 626         if (!list_empty(&res->lr_waiting)) {
 627                 ldlm_resource_dump(D_ERROR, res);
 628                 LBUG();
 629         }
 630
 631         if (!list_empty(&res->lr_children)) {
 632                 ldlm_resource_dump(D_ERROR, res);
 633                 LBUG();
 634         }
 635
 636         ns->ns_refcount--;
 637         list_del_init(&res->lr_hash);
 638         list_del_init(&res->lr_childof);
 639
 640         ns->ns_resources--;
 641         if (ns->ns_resources == 0)
 642                 wake_up(&ns->ns_waitq);
 643 }
 644
 645 /* Returns 1 if the resource was freed, 0 if it remains. */
 646 int ldlm_resource_putref(struct ldlm_resource *res)
 647 {
 648         struct ldlm_namespace *ns = res->lr_namespace;
 649         int rc = 0;
 650         ENTRY;
 651
 652         CDEBUG(D_INFO, "putref res: %p count: %d\n", res,
 653                atomic_read(&res->lr_refcount) - 1);
 654         LASSERT(atomic_read(&res->lr_refcount) > 0);
 655         LASSERT(atomic_read(&res->lr_refcount) < LI_POISON);
 656
 657         LASSERT(atomic_read(&res->lr_refcount) >= 0);
 658         if (atomic_dec_and_lock(&res->lr_refcount, &ns->ns_hash_lock)) {
 659                 __ldlm_resource_putref_final(res);
 660                 spin_unlock(&ns->ns_hash_lock);
 661                 if (res->lr_lvb_data)
 662                         OBD_FREE(res->lr_lvb_data, res->lr_lvb_len);
 663                 OBD_SLAB_FREE(res, ldlm_resource_slab, sizeof *res);
 664                 rc = 1;
 665         }
 666
 667         RETURN(rc);
 668 }
 669
 670 /* Returns 1 if the resource was freed, 0 if it remains. */
 671 int ldlm_resource_putref_locked(struct ldlm_resource *res)
 672 {
 673         int rc = 0;
 674         ENTRY;
 675
 676         CDEBUG(D_INFO, "putref res: %p count: %d\n", res,
 677                atomic_read(&res->lr_refcount) - 1);
 678         LASSERT(atomic_read(&res->lr_refcount) > 0);
 679         LASSERT(atomic_read(&res->lr_refcount) < LI_POISON);
 680
 681         LASSERT(atomic_read(&res->lr_refcount) >= 0);
 682         if (atomic_dec_and_test(&res->lr_refcount)) {
 683                 __ldlm_resource_putref_final(res);
 684                 if (res->lr_lvb_data)
 685                         OBD_FREE(res->lr_lvb_data, res->lr_lvb_len);
 686                 OBD_SLAB_FREE(res, ldlm_resource_slab, sizeof *res);
 687                 rc = 1;
 688         }
 689
 690         RETURN(rc);
 691 }
 692
 693 void ldlm_resource_add_lock(struct ldlm_resource *res, struct list_head *head,
 694                             struct ldlm_lock *lock)
 695 {
 696         check_res_locked(res);
 697
 698         ldlm_resource_dump(D_OTHER, res);
 699         CDEBUG(D_OTHER, "About to add this lock:\n");
 700         ldlm_lock_dump(D_OTHER, lock, 0);
 701
 702         if (lock->l_destroyed) {
 703                 CDEBUG(D_OTHER, "Lock destroyed, not adding to resource\n");
 704                 return;
 705         }
 706
 707         LASSERT(list_empty(&lock->l_res_link));
 708
 709         list_add_tail(&lock->l_res_link, head);
 710 }
 711
 712 void ldlm_resource_insert_lock_after(struct ldlm_lock *original,
 713                                      struct ldlm_lock *new)
 714 {
 715         struct ldlm_resource *res = original->l_resource;
 716
 717         check_res_locked(res);
 718
 719         ldlm_resource_dump(D_OTHER, res);
 720         CDEBUG(D_OTHER, "About to insert this lock after %p:\n", original);
 721         ldlm_lock_dump(D_OTHER, new, 0);
 722
 723         if (new->l_destroyed) {
 724                 CDEBUG(D_OTHER, "Lock destroyed, not adding to resource\n");
 725                 return;
 726         }
 727
 728         LASSERT(list_empty(&new->l_res_link));
 729         list_add(&new->l_res_link, &original->l_res_link);
 730 }
 731
 732 void ldlm_resource_unlink_lock(struct ldlm_lock *lock)
 733 {
 734         check_res_locked(lock->l_resource);
 735         list_del_init(&lock->l_res_link);
 736 }
 737
 738 void ldlm_res2desc(struct ldlm_resource *res, struct ldlm_resource_desc *desc)
 739 {
 740         desc->lr_type = res->lr_type;
 741         memcpy(&desc->lr_name, &res->lr_name, sizeof(desc->lr_name));
 742 }
 743
 744 void ldlm_dump_all_namespaces(int level)
 745 {
 746         struct list_head *tmp;
 747
 748         down(&ldlm_namespace_lock);
 749
 750         list_for_each(tmp, &ldlm_namespace_list) {
 751                 struct ldlm_namespace *ns;
 752                 ns = list_entry(tmp, struct ldlm_namespace, ns_list_chain);
 753                 ldlm_namespace_dump(level, ns);
 754         }
 755
 756         up(&ldlm_namespace_lock);
 757 }
 758
 759 void ldlm_namespace_dump(int level, struct ldlm_namespace *ns)
 760 {
 761         struct list_head *tmp;
 762
 763         CDEBUG(level, "--- Namespace: %s (rc: %d, client: %d)\n",
 764                ns->ns_name, ns->ns_refcount, ns->ns_client);
 765
 766         if (time_before(jiffies, ns->ns_next_dump))
 767                 return;
 768
 769         spin_lock(&ns->ns_hash_lock);
 770         tmp = ns->ns_root_list.next;
 771         while (tmp != &ns->ns_root_list) {
 772                 struct ldlm_resource *res;
 773                 res = list_entry(tmp, struct ldlm_resource, lr_childof);
 774
 775                 ldlm_resource_getref(res);
 776                 spin_unlock(&ns->ns_hash_lock);
 777
 778                 lock_res(res);
 779                 ldlm_resource_dump(level, res);
 780                 unlock_res(res);
 781
 782                 spin_lock(&ns->ns_hash_lock);
 783                 tmp = tmp->next;
 784                 ldlm_resource_putref_locked(res);
 785         }
 786         ns->ns_next_dump = jiffies + 10 * HZ;
 787         spin_unlock(&ns->ns_hash_lock);
 788 }
 789
 790 void ldlm_resource_dump(int level, struct ldlm_resource *res)
 791 {
 792         struct list_head *tmp;
 793         int pos;
 794
 795         if (RES_NAME_SIZE != 4)
 796                 LBUG();
 797
 798         CDEBUG(level, "--- Resource: %p ("LPU64"/"LPU64"/"LPU64"/"LPU64
 799                ") (rc: %d)\n", res, res->lr_name.name[0], res->lr_name.name[1],
 800                res->lr_name.name[2], res->lr_name.name[3],
 801                atomic_read(&res->lr_refcount));
 802
 803         if (!list_empty(&res->lr_granted)) {
 804                 pos = 0;
 805                 CDEBUG(level, "Granted locks:\n");
 806                 list_for_each(tmp, &res->lr_granted) {
 807                         struct ldlm_lock *lock;
 808                         lock = list_entry(tmp, struct ldlm_lock, l_res_link);
 809                         ldlm_lock_dump(level, lock, ++pos);
 810                 }
 811         }
 812         if (!list_empty(&res->lr_converting)) {
 813                 pos = 0;
 814                 CDEBUG(level, "Converting locks:\n");
 815                 list_for_each(tmp, &res->lr_converting) {
 816                         struct ldlm_lock *lock;
 817                         lock = list_entry(tmp, struct ldlm_lock, l_res_link);
 818                         ldlm_lock_dump(level, lock, ++pos);
 819                 }
 820         }
 821         if (!list_empty(&res->lr_waiting)) {
 822                 pos = 0;
 823                 CDEBUG(level, "Waiting locks:\n");
 824                 list_for_each(tmp, &res->lr_waiting) {
 825                         struct ldlm_lock *lock;
 826                         lock = list_entry(tmp, struct ldlm_lock, l_res_link);
 827                         ldlm_lock_dump(level, lock, ++pos);
 828                 }
 829         }
 830 }