lustre/ldlm/ldlm_lock.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: Peter Braam <braam@clusterfs.com>
   6  *   Author: Phil Schwan <phil@clusterfs.com>
   7  *
   8  *   This file is part of the Lustre file system, http://www.lustre.org
   9  *   Lustre is a trademark of Cluster File Systems, Inc.
  10  *
  11  *   You may have signed or agreed to another license before downloading
  12  *   this software.  If so, you are bound by the terms and conditions
  13  *   of that agreement, and the following does not apply to you.  See the
  14  *   LICENSE file included with this distribution for more information.
  15  *
  16  *   If you did not agree to a different license, then this copy of Lustre
  17  *   is open source software; you can redistribute it and/or modify it
  18  *   under the terms of version 2 of the GNU General Public License as
  19  *   published by the Free Software Foundation.
  20  *
  21  *   In either case, Lustre is distributed in the hope that it will be
  22  *   useful, but WITHOUT ANY WARRANTY; without even the implied warranty
  23  *   of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  24  *   license text for more details.
  25  */
  26
  27 #define DEBUG_SUBSYSTEM S_LDLM
  28
  29 #ifdef __KERNEL__
  30 # include <libcfs/libcfs.h>
  31 # ifndef HAVE_VFS_INTENT_PATCHES
  32 # include <linux/lustre_intent.h>
  33 # endif
  34 #else
  35 # include <liblustre.h>
  36 # include <libcfs/kp30.h>
  37 #endif
  38
  39 #include <obd_class.h>
  40 #include "ldlm_internal.h"
  41
  42 /* lock's skip list pointers fix mode */
  43 #define LDLM_JOIN_NONE          0
  44 #define LDLM_MODE_JOIN_RIGHT    1
  45 #define LDLM_MODE_JOIN_LEFT     (1 << 1)
  46 #define LDLM_POLICY_JOIN_RIGHT  (1 << 2)
  47 #define LDLM_POLICY_JOIN_LEFT   (1 << 3)
  48
  49 /* lock types */
  50 char *ldlm_lockname[] = {
  51         [0] "--",
  52         [LCK_EX] "EX",
  53         [LCK_PW] "PW",
  54         [LCK_PR] "PR",
  55         [LCK_CW] "CW",
  56         [LCK_CR] "CR",
  57         [LCK_NL] "NL",
  58         [LCK_GROUP] "GROUP"
  59 };
  60
  61 char *ldlm_typename[] = {
  62         [LDLM_PLAIN] "PLN",
  63         [LDLM_EXTENT] "EXT",
  64         [LDLM_FLOCK] "FLK",
  65         [LDLM_IBITS] "IBT",
  66 };
  67
  68 char *ldlm_it2str(int it)
  69 {
  70         switch (it) {
  71         case IT_OPEN:
  72                 return "open";
  73         case IT_CREAT:
  74                 return "creat";
  75         case (IT_OPEN | IT_CREAT):
  76                 return "open|creat";
  77         case IT_READDIR:
  78                 return "readdir";
  79         case IT_GETATTR:
  80                 return "getattr";
  81         case IT_LOOKUP:
  82                 return "lookup";
  83         case IT_UNLINK:
  84                 return "unlink";
  85         case IT_GETXATTR:
  86                 return "getxattr";
  87         default:
  88                 CERROR("Unknown intent %d\n", it);
  89                 return "UNKNOWN";
  90         }
  91 }
  92
  93 extern cfs_mem_cache_t *ldlm_lock_slab;
  94
  95 static ldlm_processing_policy ldlm_processing_policy_table[] = {
  96         [LDLM_PLAIN] ldlm_process_plain_lock,
  97         [LDLM_EXTENT] ldlm_process_extent_lock,
  98 #ifdef __KERNEL__
  99         [LDLM_FLOCK] ldlm_process_flock_lock,
 100 #endif
 101         [LDLM_IBITS] ldlm_process_inodebits_lock,
 102 };
 103
 104 ldlm_processing_policy ldlm_get_processing_policy(struct ldlm_resource *res)
 105 {
 106         return ldlm_processing_policy_table[res->lr_type];
 107 }
 108
 109 void ldlm_register_intent(struct ldlm_namespace *ns, ldlm_res_policy arg)
 110 {
 111         ns->ns_policy = arg;
 112 }
 113
 114 /*
 115  * REFCOUNTED LOCK OBJECTS
 116  */
 117
 118
 119 /*
 120  * Lock refcounts, during creation:
 121  *   - one special one for allocation, dec'd only once in destroy
 122  *   - one for being a lock that's in-use
 123  *   - one for the addref associated with a new lock
 124  */
 125 struct ldlm_lock *ldlm_lock_get(struct ldlm_lock *lock)
 126 {
 127         atomic_inc(&lock->l_refc);
 128         return lock;
 129 }
 130
 131 static void ldlm_lock_free(struct ldlm_lock *lock, size_t size)
 132 {
 133         LASSERT(size == sizeof(*lock));
 134         OBD_SLAB_FREE(lock, ldlm_lock_slab, sizeof(*lock));
 135 }
 136
 137 void ldlm_lock_put(struct ldlm_lock *lock)
 138 {
 139         ENTRY;
 140
 141         LASSERT(lock->l_resource != LP_POISON);
 142         LASSERT(atomic_read(&lock->l_refc) > 0);
 143         if (atomic_dec_and_test(&lock->l_refc)) {
 144                 struct ldlm_resource *res;
 145
 146                 LDLM_DEBUG(lock,
 147                            "final lock_put on destroyed lock, freeing it.");
 148
 149                 res = lock->l_resource;
 150                 LASSERT(lock->l_destroyed);
 151                 LASSERT(list_empty(&lock->l_res_link));
 152                 LASSERT(list_empty(&lock->l_pending_chain));
 153
 154                 atomic_dec(&res->lr_namespace->ns_locks);
 155                 ldlm_resource_putref(res);
 156                 lock->l_resource = NULL;
 157                 if (lock->l_export) {
 158                         class_export_put(lock->l_export);
 159                         lock->l_export = NULL;
 160                 }
 161
 162                 if (lock->l_lvb_data != NULL)
 163                         OBD_FREE(lock->l_lvb_data, lock->l_lvb_len);
 164
 165                 ldlm_interval_free(ldlm_interval_detach(lock));
 166                 OBD_FREE_RCU_CB(lock, sizeof(*lock), &lock->l_handle,
 167                                 ldlm_lock_free);
 168         }
 169
 170         EXIT;
 171 }
 172
 173 int ldlm_lock_remove_from_lru_nolock(struct ldlm_lock *lock)
 174 {
 175         int rc = 0;
 176         if (!list_empty(&lock->l_lru)) {
 177                 struct ldlm_namespace *ns = lock->l_resource->lr_namespace;
 178                 LASSERT(lock->l_resource->lr_type != LDLM_FLOCK);
 179                 list_del_init(&lock->l_lru);
 180                 ns->ns_nr_unused--;
 181                 LASSERT(ns->ns_nr_unused >= 0);
 182                 rc = 1;
 183         }
 184         return rc;
 185 }
 186
 187 int ldlm_lock_remove_from_lru(struct ldlm_lock *lock)
 188 {
 189         struct ldlm_namespace *ns = lock->l_resource->lr_namespace;
 190         int rc;
 191         ENTRY;
 192         spin_lock(&ns->ns_unused_lock);
 193         rc = ldlm_lock_remove_from_lru_nolock(lock);
 194         spin_unlock(&ns->ns_unused_lock);
 195         EXIT;
 196         return rc;
 197 }
 198
 199 void ldlm_lock_add_to_lru_nolock(struct ldlm_lock *lock)
 200 {
 201         struct ldlm_namespace *ns = lock->l_resource->lr_namespace;
 202         lock->l_last_used = cfs_time_current();
 203         LASSERT(list_empty(&lock->l_lru));
 204         list_add_tail(&lock->l_lru, &ns->ns_unused_list);
 205         LASSERT(ns->ns_nr_unused >= 0);
 206         ns->ns_nr_unused++;
 207 }
 208
 209 void ldlm_lock_add_to_lru(struct ldlm_lock *lock)
 210 {
 211         struct ldlm_namespace *ns = lock->l_resource->lr_namespace;
 212         ENTRY;
 213         spin_lock(&ns->ns_unused_lock);
 214         ldlm_lock_add_to_lru_nolock(lock);
 215         spin_unlock(&ns->ns_unused_lock);
 216         EXIT;
 217 }
 218
 219 void ldlm_lock_touch_in_lru(struct ldlm_lock *lock)
 220 {
 221         struct ldlm_namespace *ns = lock->l_resource->lr_namespace;
 222         ENTRY;
 223         spin_lock(&ns->ns_unused_lock);
 224         if (!list_empty(&lock->l_lru)) {
 225                 ldlm_lock_remove_from_lru_nolock(lock);
 226                 ldlm_lock_add_to_lru_nolock(lock);
 227         }
 228         spin_unlock(&ns->ns_unused_lock);
 229         EXIT;
 230 }
 231
 232 /* This used to have a 'strict' flag, which recovery would use to mark an
 233  * in-use lock as needing-to-die.  Lest I am ever tempted to put it back, I
 234  * shall explain why it's gone: with the new hash table scheme, once you call
 235  * ldlm_lock_destroy, you can never drop your final references on this lock.
 236  * Because it's not in the hash table anymore.  -phil */
 237 int ldlm_lock_destroy_internal(struct ldlm_lock *lock)
 238 {
 239         ENTRY;
 240
 241         if (lock->l_readers || lock->l_writers) {
 242                 LDLM_ERROR(lock, "lock still has references");
 243                 ldlm_lock_dump(D_ERROR, lock, 0);
 244                 LBUG();
 245         }
 246
 247         if (!list_empty(&lock->l_res_link)) {
 248                 LDLM_ERROR(lock, "lock still on resource");
 249                 ldlm_lock_dump(D_ERROR, lock, 0);
 250                 LBUG();
 251         }
 252
 253         if (lock->l_destroyed) {
 254                 LASSERT(list_empty(&lock->l_lru));
 255                 EXIT;
 256                 return 0;
 257         }
 258         lock->l_destroyed = 1;
 259
 260         if (lock->l_export)
 261                 spin_lock(&lock->l_export->exp_ldlm_data.led_lock);
 262         list_del_init(&lock->l_export_chain);
 263         if (lock->l_export)
 264                 spin_unlock(&lock->l_export->exp_ldlm_data.led_lock);
 265
 266         ldlm_lock_remove_from_lru(lock);
 267         class_handle_unhash(&lock->l_handle);
 268
 269 #if 0
 270         /* Wake anyone waiting for this lock */
 271         /* FIXME: I should probably add yet another flag, instead of using
 272          * l_export to only call this on clients */
 273         if (lock->l_export)
 274                 class_export_put(lock->l_export);
 275         lock->l_export = NULL;
 276         if (lock->l_export && lock->l_completion_ast)
 277                 lock->l_completion_ast(lock, 0);
 278 #endif
 279         EXIT;
 280         return 1;
 281 }
 282
 283 void ldlm_lock_destroy(struct ldlm_lock *lock)
 284 {
 285         int first;
 286         ENTRY;
 287         lock_res_and_lock(lock);
 288         first = ldlm_lock_destroy_internal(lock);
 289         unlock_res_and_lock(lock);
 290
 291         /* drop reference from hashtable only for first destroy */
 292         if (first)
 293                 LDLM_LOCK_PUT(lock);
 294         EXIT;
 295 }
 296
 297 void ldlm_lock_destroy_nolock(struct ldlm_lock *lock)
 298 {
 299         int first;
 300         ENTRY;
 301         first = ldlm_lock_destroy_internal(lock);
 302         /* drop reference from hashtable only for first destroy */
 303         if (first)
 304                 LDLM_LOCK_PUT(lock);
 305         EXIT;
 306 }
 307
 308 /* this is called by portals_handle2object with the handle lock taken */
 309 static void lock_handle_addref(void *lock)
 310 {
 311         LDLM_LOCK_GET((struct ldlm_lock *)lock);
 312 }
 313
 314 /*
 315  * usage: pass in a resource on which you have done ldlm_resource_get
 316  *        pass in a parent lock on which you have done a ldlm_lock_get
 317  *        after return, ldlm_*_put the resource and parent
 318  * returns: lock with refcount 2 - one for current caller and one for remote
 319  */
 320 static struct ldlm_lock *ldlm_lock_new(struct ldlm_resource *resource)
 321 {
 322         struct ldlm_lock *lock;
 323         ENTRY;
 324
 325         if (resource == NULL)
 326                 LBUG();
 327
 328         OBD_SLAB_ALLOC(lock, ldlm_lock_slab, CFS_ALLOC_IO, sizeof(*lock));
 329         if (lock == NULL)
 330                 RETURN(NULL);
 331
 332         spin_lock_init(&lock->l_lock);
 333         lock->l_resource = ldlm_resource_getref(resource);
 334
 335         atomic_set(&lock->l_refc, 2);
 336         CFS_INIT_LIST_HEAD(&lock->l_res_link);
 337         CFS_INIT_LIST_HEAD(&lock->l_lru);
 338         CFS_INIT_LIST_HEAD(&lock->l_export_chain);
 339         CFS_INIT_LIST_HEAD(&lock->l_pending_chain);
 340         CFS_INIT_LIST_HEAD(&lock->l_bl_ast);
 341         CFS_INIT_LIST_HEAD(&lock->l_cp_ast);
 342         cfs_waitq_init(&lock->l_waitq);
 343         lock->l_blocking_lock = NULL;
 344         lock->l_sl_mode.prev = NULL;
 345         lock->l_sl_mode.next = NULL;
 346         lock->l_sl_policy.prev = NULL;
 347         lock->l_sl_policy.next = NULL;
 348
 349         atomic_inc(&resource->lr_namespace->ns_locks);
 350         CFS_INIT_LIST_HEAD(&lock->l_handle.h_link);
 351         class_handle_hash(&lock->l_handle, lock_handle_addref);
 352
 353         RETURN(lock);
 354 }
 355
 356 int ldlm_lock_change_resource(struct ldlm_namespace *ns, struct ldlm_lock *lock,
 357                               const struct ldlm_res_id *new_resid)
 358 {
 359         struct ldlm_resource *oldres = lock->l_resource;
 360         struct ldlm_resource *newres;
 361         int type;
 362         ENTRY;
 363
 364         LASSERT(ns_is_client(ns));
 365
 366         lock_res_and_lock(lock);
 367         if (memcmp(new_resid, &lock->l_resource->lr_name,
 368                    sizeof(lock->l_resource->lr_name)) == 0) {
 369                 /* Nothing to do */
 370                 unlock_res_and_lock(lock);
 371                 RETURN(0);
 372         }
 373
 374         LASSERT(new_resid->name[0] != 0);
 375
 376         /* This function assumes that the lock isn't on any lists */
 377         LASSERT(list_empty(&lock->l_res_link));
 378
 379         type = oldres->lr_type;
 380         unlock_res_and_lock(lock);
 381
 382         newres = ldlm_resource_get(ns, NULL, new_resid, type, 1);
 383         if (newres == NULL) {
 384                 LBUG();
 385                 RETURN(-ENOMEM);
 386         }
 387
 388         lock_res_and_lock(lock);
 389         LASSERT(memcmp(new_resid, &lock->l_resource->lr_name,
 390                        sizeof(lock->l_resource->lr_name)) != 0);
 391         lock_res(newres);
 392         lock->l_resource = newres;
 393         unlock_res(oldres);
 394         unlock_res_and_lock(lock);
 395
 396         /* ...and the flowers are still standing! */
 397         ldlm_resource_putref(oldres);
 398
 399         RETURN(0);
 400 }
 401
 402 /*
 403  *  HANDLES
 404  */
 405
 406 void ldlm_lock2handle(const struct ldlm_lock *lock, struct lustre_handle *lockh)
 407 {
 408         lockh->cookie = lock->l_handle.h_cookie;
 409 }
 410
 411 /* if flags: atomically get the lock and set the flags.
 412  *           Return NULL if flag already set
 413  */
 414
 415 struct ldlm_lock *__ldlm_handle2lock(const struct lustre_handle *handle,
 416                                      int flags)
 417 {
 418         struct ldlm_namespace *ns;
 419         struct ldlm_lock *lock, *retval = NULL;
 420         ENTRY;
 421
 422         LASSERT(handle);
 423
 424         lock = class_handle2object(handle->cookie);
 425         if (lock == NULL)
 426                 RETURN(NULL);
 427
 428         LASSERT(lock->l_resource != NULL);
 429         ns = lock->l_resource->lr_namespace;
 430         LASSERT(ns != NULL);
 431
 432         lock_res_and_lock(lock);
 433
 434         /* It's unlikely but possible that someone marked the lock as
 435          * destroyed after we did handle2object on it */
 436         if (lock->l_destroyed) {
 437                 unlock_res_and_lock(lock);
 438                 CDEBUG(D_INFO, "lock already destroyed: lock %p\n", lock);
 439                 LDLM_LOCK_PUT(lock);
 440                 GOTO(out, retval);
 441         }
 442
 443         if (flags && (lock->l_flags & flags)) {
 444                 unlock_res_and_lock(lock);
 445                 LDLM_LOCK_PUT(lock);
 446                 GOTO(out, retval);
 447         }
 448
 449         if (flags)
 450                 lock->l_flags |= flags;
 451
 452         unlock_res_and_lock(lock);
 453         retval = lock;
 454         EXIT;
 455  out:
 456         return retval;
 457 }
 458
 459 struct ldlm_lock *ldlm_handle2lock_ns(struct ldlm_namespace *ns,
 460                                       const struct lustre_handle *handle)
 461 {
 462         struct ldlm_lock *retval = NULL;
 463         retval = __ldlm_handle2lock(handle, 0);
 464         return retval;
 465 }
 466
 467 void ldlm_lock2desc(struct ldlm_lock *lock, struct ldlm_lock_desc *desc)
 468 {
 469         struct obd_export *exp = lock->l_export?:lock->l_conn_export;
 470         /* INODEBITS_INTEROP: If the other side does not support
 471          * inodebits, reply with a plain lock descriptor.
 472          */
 473         if ((lock->l_resource->lr_type == LDLM_IBITS) &&
 474             (exp && !(exp->exp_connect_flags & OBD_CONNECT_IBITS))) {
 475                 struct ldlm_resource res = *lock->l_resource;
 476
 477                 /* Make sure all the right bits are set in this lock we
 478                    are going to pass to client */
 479                 LASSERTF(lock->l_policy_data.l_inodebits.bits ==
 480                          (MDS_INODELOCK_LOOKUP|MDS_INODELOCK_UPDATE),
 481                          "Inappropriate inode lock bits during "
 482                          "conversion " LPU64 "\n",
 483                          lock->l_policy_data.l_inodebits.bits);
 484                 res.lr_type = LDLM_PLAIN;
 485                 ldlm_res2desc(&res, &desc->l_resource);
 486                 /* Convert "new" lock mode to something old client can
 487                    understand */
 488                 if ((lock->l_req_mode == LCK_CR) ||
 489                     (lock->l_req_mode == LCK_CW))
 490                         desc->l_req_mode = LCK_PR;
 491                 else
 492                         desc->l_req_mode = lock->l_req_mode;
 493                 if ((lock->l_granted_mode == LCK_CR) ||
 494                     (lock->l_granted_mode == LCK_CW)) {
 495                         desc->l_granted_mode = LCK_PR;
 496                 } else {
 497                         /* We never grant PW/EX locks to clients */
 498                         LASSERT((lock->l_granted_mode != LCK_PW) &&
 499                                 (lock->l_granted_mode != LCK_EX));
 500                         desc->l_granted_mode = lock->l_granted_mode;
 501                 }
 502
 503                 /* We do not copy policy here, because there is no
 504                    policy for plain locks */
 505         } else {
 506                 ldlm_res2desc(lock->l_resource, &desc->l_resource);
 507                 desc->l_req_mode = lock->l_req_mode;
 508                 desc->l_granted_mode = lock->l_granted_mode;
 509                 desc->l_policy_data = lock->l_policy_data;
 510         }
 511 }
 512
 513 void ldlm_add_bl_work_item(struct ldlm_lock *lock, struct ldlm_lock *new,
 514                            struct list_head *work_list)
 515 {
 516         if ((lock->l_flags & LDLM_FL_AST_SENT) == 0) {
 517                 LDLM_DEBUG(lock, "lock incompatible; sending blocking AST.");
 518                 lock->l_flags |= LDLM_FL_AST_SENT;
 519                 /* If the enqueuing client said so, tell the AST recipient to
 520                  * discard dirty data, rather than writing back. */
 521                 if (new->l_flags & LDLM_AST_DISCARD_DATA)
 522                         lock->l_flags |= LDLM_FL_DISCARD_DATA;
 523                 LASSERT(list_empty(&lock->l_bl_ast));
 524                 list_add(&lock->l_bl_ast, work_list);
 525                 LDLM_LOCK_GET(lock);
 526                 LASSERT(lock->l_blocking_lock == NULL);
 527                 lock->l_blocking_lock = LDLM_LOCK_GET(new);
 528         }
 529 }
 530
 531 void ldlm_add_cp_work_item(struct ldlm_lock *lock, struct list_head *work_list)
 532 {
 533         if ((lock->l_flags & LDLM_FL_CP_REQD) == 0) {
 534                 lock->l_flags |= LDLM_FL_CP_REQD;
 535                 LDLM_DEBUG(lock, "lock granted; sending completion AST.");
 536                 LASSERT(list_empty(&lock->l_cp_ast));
 537                 list_add(&lock->l_cp_ast, work_list);
 538                 LDLM_LOCK_GET(lock);
 539         }
 540 }
 541
 542 /* must be called with lr_lock held */
 543 void ldlm_add_ast_work_item(struct ldlm_lock *lock, struct ldlm_lock *new,
 544                                 struct list_head *work_list)
 545 {
 546         ENTRY;
 547         check_res_locked(lock->l_resource);
 548         if (new)
 549                 ldlm_add_bl_work_item(lock, new, work_list);
 550         else
 551                 ldlm_add_cp_work_item(lock, work_list);
 552         EXIT;
 553 }
 554
 555 void ldlm_lock_addref(struct lustre_handle *lockh, __u32 mode)
 556 {
 557         struct ldlm_lock *lock;
 558
 559         lock = ldlm_handle2lock(lockh);
 560         LASSERT(lock != NULL);
 561         ldlm_lock_addref_internal(lock, mode);
 562         LDLM_LOCK_PUT(lock);
 563 }
 564
 565 void ldlm_lock_addref_internal_nolock(struct ldlm_lock *lock, __u32 mode)
 566 {
 567         ldlm_lock_remove_from_lru(lock);
 568         if (mode & (LCK_NL | LCK_CR | LCK_PR))
 569                 lock->l_readers++;
 570         if (mode & (LCK_EX | LCK_CW | LCK_PW | LCK_GROUP))
 571                 lock->l_writers++;
 572         LDLM_LOCK_GET(lock);
 573         LDLM_DEBUG(lock, "ldlm_lock_addref(%s)", ldlm_lockname[mode]);
 574 }
 575
 576 /* only called for local locks */
 577 void ldlm_lock_addref_internal(struct ldlm_lock *lock, __u32 mode)
 578 {
 579         lock_res_and_lock(lock);
 580         ldlm_lock_addref_internal_nolock(lock, mode);
 581         unlock_res_and_lock(lock);
 582 }
 583
 584 void ldlm_lock_decref_internal(struct ldlm_lock *lock, __u32 mode)
 585 {
 586         struct ldlm_namespace *ns;
 587         ENTRY;
 588
 589         lock_res_and_lock(lock);
 590
 591         ns = lock->l_resource->lr_namespace;
 592
 593         LDLM_DEBUG(lock, "ldlm_lock_decref(%s)", ldlm_lockname[mode]);
 594         if (mode & (LCK_NL | LCK_CR | LCK_PR)) {
 595                 LASSERT(lock->l_readers > 0);
 596                 lock->l_readers--;
 597         }
 598         if (mode & (LCK_EX | LCK_CW | LCK_PW | LCK_GROUP)) {
 599                 LASSERT(lock->l_writers > 0);
 600                 lock->l_writers--;
 601         }
 602
 603         if (lock->l_flags & LDLM_FL_LOCAL &&
 604             !lock->l_readers && !lock->l_writers) {
 605                 /* If this is a local lock on a server namespace and this was
 606                  * the last reference, cancel the lock. */
 607                 CDEBUG(D_INFO, "forcing cancel of local lock\n");
 608                 lock->l_flags |= LDLM_FL_CBPENDING;
 609         }
 610
 611         if (!lock->l_readers && !lock->l_writers &&
 612             (lock->l_flags & LDLM_FL_CBPENDING)) {
 613                 /* If we received a blocked AST and this was the last reference,
 614                  * run the callback. */
 615                 if (ns_is_server(ns) && lock->l_export)
 616                         CERROR("FL_CBPENDING set on non-local lock--just a "
 617                                "warning\n");
 618
 619                 LDLM_DEBUG(lock, "final decref done on cbpending lock");
 620
 621                 LDLM_LOCK_GET(lock); /* dropped by bl thread */
 622                 ldlm_lock_remove_from_lru(lock);
 623                 unlock_res_and_lock(lock);
 624                 if ((lock->l_flags & LDLM_FL_ATOMIC_CB) ||
 625                     ldlm_bl_to_thread_lock(ns, NULL, lock) != 0)
 626                         ldlm_handle_bl_callback(ns, NULL, lock);
 627         } else if (ns_is_client(ns) &&
 628                    !lock->l_readers && !lock->l_writers &&
 629                    !(lock->l_flags & LDLM_FL_NO_LRU) &&
 630                    !(lock->l_flags & LDLM_FL_BL_AST)) {
 631                 /* If this is a client-side namespace and this was the last
 632                  * reference, put it on the LRU. */
 633                 ldlm_lock_add_to_lru(lock);
 634                 unlock_res_and_lock(lock);
 635                 /* Call ldlm_cancel_lru() only if EARLY_CANCEL and LRU RESIZE
 636                  * are not supported by the server, otherwise, it is done on
 637                  * enqueue. */
 638                 if (!exp_connect_cancelset(lock->l_conn_export) &&
 639                     !ns_connect_lru_resize(ns))
 640                         ldlm_cancel_lru(ns, 0, LDLM_ASYNC, 0);
 641         } else {
 642                 unlock_res_and_lock(lock);
 643         }
 644
 645         LDLM_LOCK_PUT(lock);    /* matches the ldlm_lock_get in addref */
 646
 647         EXIT;
 648 }
 649
 650 void ldlm_lock_decref(struct lustre_handle *lockh, __u32 mode)
 651 {
 652         struct ldlm_lock *lock = __ldlm_handle2lock(lockh, 0);
 653         LASSERTF(lock != NULL, "Non-existing lock: "LPX64"\n", lockh->cookie);
 654         ldlm_lock_decref_internal(lock, mode);
 655         LDLM_LOCK_PUT(lock);
 656 }
 657
 658 /* This will drop a lock reference and mark it for destruction, but will not
 659  * necessarily cancel the lock before returning. */
 660 void ldlm_lock_decref_and_cancel(struct lustre_handle *lockh, __u32 mode)
 661 {
 662         struct ldlm_lock *lock = __ldlm_handle2lock(lockh, 0);
 663         ENTRY;
 664
 665         LASSERT(lock != NULL);
 666
 667         LDLM_DEBUG(lock, "ldlm_lock_decref(%s)", ldlm_lockname[mode]);
 668         lock_res_and_lock(lock);
 669         lock->l_flags |= LDLM_FL_CBPENDING;
 670         unlock_res_and_lock(lock);
 671         ldlm_lock_decref_internal(lock, mode);
 672         LDLM_LOCK_PUT(lock);
 673 }
 674
 675 /*
 676  * search_granted_lock
 677  *
 678  * Description:
 679  *      Finds a position to insert the new lock.
 680  * Parameters:
 681  *      queue [input]:  the granted list where search acts on;
 682  *      req [input]:    the lock whose position to be located;
 683  *      lockp [output]: the position where the lock should be inserted before, or
 684  *                      NULL indicating @req should be appended to @queue.
 685  * Return Values:
 686  *      Bit-masks combination of following values indicating in which way the
 687  *      lock need to be inserted.
 688  *      - LDLM_JOIN_NONE:       noting about skip list needs to be fixed;
 689  *      - LDLM_MODE_JOIN_RIGHT: @req needs join right becoming the head of a
 690  *                              mode group;
 691  *      - LDLM_POLICY_JOIN_RIGHT: @req needs join right becoming the head of
 692  *                                a policy group.
 693  * NOTE: called by
 694  *  - ldlm_grant_lock_with_skiplist
 695  */
 696 static int search_granted_lock(struct list_head *queue,
 697                         struct ldlm_lock *req,
 698                         struct ldlm_lock **lockp)
 699 {
 700         struct list_head *tmp, *tmp_tail;
 701         struct ldlm_lock *lock, *mode_head_lock;
 702         int rc = LDLM_JOIN_NONE;
 703         ENTRY;
 704
 705         list_for_each(tmp, queue) {
 706                 lock = list_entry(tmp, struct ldlm_lock, l_res_link);
 707
 708                 if (lock->l_req_mode != req->l_req_mode) {
 709                         if (LDLM_SL_HEAD(&lock->l_sl_mode))
 710                                 tmp = &list_entry(lock->l_sl_mode.next,
 711                                                   struct ldlm_lock,
 712                                                   l_sl_mode)->l_res_link;
 713                         continue;
 714                 }
 715
 716                 /* found the same mode group */
 717                 if (lock->l_resource->lr_type == LDLM_PLAIN) {
 718                         *lockp = lock;
 719                         rc = LDLM_MODE_JOIN_RIGHT;
 720                         GOTO(out, rc);
 721                 } else if (lock->l_resource->lr_type == LDLM_IBITS) {
 722                         tmp_tail = tmp;
 723                         if (LDLM_SL_HEAD(&lock->l_sl_mode))
 724                                 tmp_tail = &list_entry(lock->l_sl_mode.next,
 725                                                        struct ldlm_lock,
 726                                                        l_sl_mode)->l_res_link;
 727                         mode_head_lock = lock;
 728                         for (;;) {
 729                                 if (lock->l_policy_data.l_inodebits.bits ==
 730                                     req->l_policy_data.l_inodebits.bits) {
 731                                         /* matched policy lock is found */
 732                                         *lockp = lock;
 733                                         rc |= LDLM_POLICY_JOIN_RIGHT;
 734
 735                                         /* if the policy group head is also a
 736                                          * mode group head or a single mode
 737                                          * group lock */
 738                                         if (LDLM_SL_HEAD(&lock->l_sl_mode) ||
 739                                             (tmp == tmp_tail &&
 740                                              LDLM_SL_EMPTY(&lock->l_sl_mode)))
 741                                                 rc |= LDLM_MODE_JOIN_RIGHT;
 742                                         GOTO(out, rc);
 743                                 }
 744
 745                                 if (LDLM_SL_HEAD(&lock->l_sl_policy))
 746                                         tmp = &list_entry(lock->l_sl_policy.next,
 747                                                           struct ldlm_lock,
 748                                                           l_sl_policy)->l_res_link;
 749
 750                                 if (tmp == tmp_tail)
 751                                         break;
 752                                 else
 753                                         tmp = tmp->next;
 754                                 lock = list_entry(tmp, struct ldlm_lock,
 755                                                   l_res_link);
 756                         }  /* for all locks in the matched mode group */
 757
 758                         /* no matched policy group is found, insert before
 759                          * the mode group head lock */
 760                         *lockp = mode_head_lock;
 761                         rc = LDLM_MODE_JOIN_RIGHT;
 762                         GOTO(out, rc);
 763                 } else {
 764                         LDLM_ERROR(lock, "is not LDLM_PLAIN or LDLM_IBITS lock");
 765                         LBUG();
 766                 }
 767         }
 768
 769         /* no matched mode group is found, append to the end */
 770         *lockp = NULL;
 771         rc = LDLM_JOIN_NONE;
 772         EXIT;
 773 out:
 774         return rc;
 775 }
 776
 777 static void ldlm_granted_list_add_lock(struct ldlm_lock *lock,
 778                                        struct ldlm_lock *lockp,
 779                                        int join)
 780 {
 781         struct ldlm_resource *res = lock->l_resource;
 782         ENTRY;
 783
 784         LASSERT(lockp || join == LDLM_JOIN_NONE);
 785
 786         check_res_locked(res);
 787
 788         ldlm_resource_dump(D_OTHER, res);
 789         CDEBUG(D_OTHER, "About to add this lock:\n");
 790         ldlm_lock_dump(D_OTHER, lock, 0);
 791
 792         if (lock->l_destroyed) {
 793                 CDEBUG(D_OTHER, "Lock destroyed, not adding to resource\n");
 794                 return;
 795         }
 796
 797         LASSERT(list_empty(&lock->l_res_link));
 798
 799         if (!lockp)
 800                 list_add_tail(&lock->l_res_link, &lock->l_resource->lr_granted);
 801         else if ((join & LDLM_MODE_JOIN_LEFT) || (join & LDLM_POLICY_JOIN_LEFT))
 802                 list_add(&lock->l_res_link, &lockp->l_res_link);
 803         else
 804                 list_add_tail(&lock->l_res_link, &lockp->l_res_link);
 805
 806         /* fix skip lists */
 807         if (join & LDLM_MODE_JOIN_RIGHT) {
 808                 LASSERT(! LDLM_SL_TAIL(&lockp->l_sl_mode));
 809                 if (LDLM_SL_EMPTY(&lockp->l_sl_mode)) {
 810                         lock->l_sl_mode.next = &lockp->l_sl_mode;
 811                         lockp->l_sl_mode.prev = &lock->l_sl_mode;
 812                 } else if (LDLM_SL_HEAD(&lockp->l_sl_mode)) {
 813                         lock->l_sl_mode.next = lockp->l_sl_mode.next;
 814                         lockp->l_sl_mode.next = NULL;
 815                         lock->l_sl_mode.next->prev = &lock->l_sl_mode;
 816                 }
 817         } else if (join & LDLM_MODE_JOIN_LEFT) {
 818                 LASSERT(! LDLM_SL_HEAD(&lockp->l_sl_mode));
 819                if (LDLM_SL_EMPTY(&lockp->l_sl_mode)) {
 820                         lock->l_sl_mode.prev = &lockp->l_sl_mode;
 821                         lockp->l_sl_mode.next = &lock->l_sl_mode;
 822                 } else if (LDLM_SL_TAIL(&lockp->l_sl_mode)) {
 823                         lock->l_sl_mode.prev = lockp->l_sl_mode.prev;
 824                         lockp->l_sl_mode.prev = NULL;
 825                         lock->l_sl_mode.prev->next = &lock->l_sl_mode;
 826                 }
 827         }
 828
 829         if (join & LDLM_POLICY_JOIN_RIGHT) {
 830                 LASSERT(! LDLM_SL_TAIL(&lockp->l_sl_policy));
 831                 if (LDLM_SL_EMPTY(&lockp->l_sl_policy)) {
 832                         lock->l_sl_policy.next = &lockp->l_sl_policy;
 833                         lockp->l_sl_policy.prev = &lock->l_sl_policy;
 834                 } else if (LDLM_SL_HEAD(&lockp->l_sl_policy)) {
 835                         lock->l_sl_policy.next = lockp->l_sl_policy.next;
 836                         lockp->l_sl_policy.next = NULL;
 837                         lock->l_sl_policy.next->prev = &lock->l_sl_policy;
 838                 }
 839         } else if (join & LDLM_POLICY_JOIN_LEFT) {
 840                 LASSERT(! LDLM_SL_HEAD(&lockp->l_sl_policy));
 841                 if (LDLM_SL_EMPTY(&lockp->l_sl_policy)) {
 842                         lock->l_sl_policy.prev = &lockp->l_sl_policy;
 843                         lockp->l_sl_policy.next = &lock->l_sl_policy;
 844                 } else if (LDLM_SL_TAIL(&lockp->l_sl_policy)) {
 845                         lock->l_sl_policy.prev = lockp->l_sl_policy.prev;
 846                         lockp->l_sl_policy.prev = NULL;
 847                         lock->l_sl_policy.prev->next = &lock->l_sl_policy;
 848                 }
 849         }
 850
 851         EXIT;
 852 }
 853
 854 static void ldlm_grant_lock_with_skiplist(struct ldlm_lock *lock)
 855 {
 856         int join = LDLM_JOIN_NONE;
 857         struct ldlm_lock *lockp = NULL;
 858         ENTRY;
 859
 860         LASSERT(lock->l_req_mode == lock->l_granted_mode);
 861
 862         join = search_granted_lock(&lock->l_resource->lr_granted, lock, &lockp);
 863         ldlm_granted_list_add_lock(lock, lockp, join);
 864         EXIT;
 865 }
 866
 867 /* NOTE: called by
 868  *  - ldlm_lock_enqueue
 869  *  - ldlm_reprocess_queue
 870  *  - ldlm_lock_convert
 871  *
 872  * must be called with lr_lock held
 873  */
 874 void ldlm_grant_lock(struct ldlm_lock *lock, struct list_head *work_list)
 875 {
 876         struct ldlm_resource *res = lock->l_resource;
 877         ENTRY;
 878
 879         check_res_locked(res);
 880
 881         lock->l_granted_mode = lock->l_req_mode;
 882         if (res->lr_type == LDLM_PLAIN || res->lr_type == LDLM_IBITS)
 883                 ldlm_grant_lock_with_skiplist(lock);
 884         else if (res->lr_type == LDLM_EXTENT)
 885                 ldlm_extent_add_lock(res, lock);
 886         else
 887                 ldlm_resource_add_lock(res, &res->lr_granted, lock);
 888
 889         if (lock->l_granted_mode < res->lr_most_restr)
 890                 res->lr_most_restr = lock->l_granted_mode;
 891
 892         if (work_list && lock->l_completion_ast != NULL)
 893                 ldlm_add_ast_work_item(lock, NULL, work_list);
 894
 895         ldlm_pool_add(&res->lr_namespace->ns_pool, lock);
 896         EXIT;
 897 }
 898
 899 /* returns a referenced lock or NULL.  See the flag descriptions below, in the
 900  * comment above ldlm_lock_match */
 901 static struct ldlm_lock *search_queue(struct list_head *queue,
 902                                       ldlm_mode_t *mode,
 903                                       ldlm_policy_data_t *policy,
 904                                       struct ldlm_lock *old_lock, int flags)
 905 {
 906         struct ldlm_lock *lock;
 907         struct list_head *tmp;
 908
 909         list_for_each(tmp, queue) {
 910                 ldlm_mode_t match;
 911
 912                 lock = list_entry(tmp, struct ldlm_lock, l_res_link);
 913
 914                 if (lock == old_lock)
 915                         continue;
 916
 917                 /* llite sometimes wants to match locks that will be
 918                  * canceled when their users drop, but we allow it to match
 919                  * if it passes in CBPENDING and the lock still has users.
 920                  * this is generally only going to be used by children
 921                  * whose parents already hold a lock so forward progress
 922                  * can still happen. */
 923                 if (lock->l_flags & LDLM_FL_CBPENDING &&
 924                     !(flags & LDLM_FL_CBPENDING))
 925                         continue;
 926                 if (lock->l_flags & LDLM_FL_CBPENDING &&
 927                     lock->l_readers == 0 && lock->l_writers == 0)
 928                         continue;
 929
 930                 if (!(lock->l_req_mode & *mode))
 931                         continue;
 932                 match = lock->l_req_mode;
 933
 934                 if (lock->l_resource->lr_type == LDLM_EXTENT &&
 935                     (lock->l_policy_data.l_extent.start >
 936                      policy->l_extent.start ||
 937                      lock->l_policy_data.l_extent.end < policy->l_extent.end))
 938                         continue;
 939
 940                 if (unlikely(match == LCK_GROUP) &&
 941                     lock->l_resource->lr_type == LDLM_EXTENT &&
 942                     lock->l_policy_data.l_extent.gid != policy->l_extent.gid)
 943                         continue;
 944
 945                 /* We match if we have existing lock with same or wider set
 946                    of bits. */
 947                 if (lock->l_resource->lr_type == LDLM_IBITS &&
 948                      ((lock->l_policy_data.l_inodebits.bits &
 949                       policy->l_inodebits.bits) !=
 950                       policy->l_inodebits.bits))
 951                         continue;
 952
 953                 if (lock->l_destroyed || (lock->l_flags & LDLM_FL_FAILED))
 954                         continue;
 955
 956                 if ((flags & LDLM_FL_LOCAL_ONLY) &&
 957                     !(lock->l_flags & LDLM_FL_LOCAL))
 958                         continue;
 959
 960                 if (flags & LDLM_FL_TEST_LOCK) {
 961                         LDLM_LOCK_GET(lock);
 962                         ldlm_lock_touch_in_lru(lock);
 963                 } else {
 964                         ldlm_lock_addref_internal_nolock(lock, match);
 965                 }
 966                 *mode = match;
 967                 return lock;
 968         }
 969
 970         return NULL;
 971 }
 972
 973 void ldlm_lock_allow_match(struct ldlm_lock *lock)
 974 {
 975         lock_res_and_lock(lock);
 976         lock->l_flags |= LDLM_FL_LVB_READY;
 977         cfs_waitq_signal(&lock->l_waitq);
 978         unlock_res_and_lock(lock);
 979 }
 980
 981 /* Can be called in two ways:
 982  *
 983  * If 'ns' is NULL, then lockh describes an existing lock that we want to look
 984  * for a duplicate of.
 985  *
 986  * Otherwise, all of the fields must be filled in, to match against.
 987  *
 988  * If 'flags' contains LDLM_FL_LOCAL_ONLY, then only match local locks on the
 989  *     server (ie, connh is NULL)
 990  * If 'flags' contains LDLM_FL_BLOCK_GRANTED, then only locks on the granted
 991  *     list will be considered
 992  * If 'flags' contains LDLM_FL_CBPENDING, then locks that have been marked
 993  *     to be canceled can still be matched as long as they still have reader
 994  *     or writer refernces
 995  * If 'flags' contains LDLM_FL_TEST_LOCK, then don't actually reference a lock,
 996  *     just tell us if we would have matched.
 997  *
 998  * Returns 1 if it finds an already-existing lock that is compatible; in this
 999  * case, lockh is filled in with a addref()ed lock
1000  *
1001  * we also check security context, if that failed we simply return 0 (to keep
1002  * caller code unchanged), the context failure will be discovered by caller
1003  * sometime later.
1004  */
1005 ldlm_mode_t ldlm_lock_match(struct ldlm_namespace *ns, int flags,
1006                             const struct ldlm_res_id *res_id, ldlm_type_t type,
1007                             ldlm_policy_data_t *policy, ldlm_mode_t mode,
1008                             struct lustre_handle *lockh)
1009 {
1010         struct ldlm_resource *res;
1011         struct ldlm_lock *lock, *old_lock = NULL;
1012         int rc = 0;
1013         ENTRY;
1014
1015         if (ns == NULL) {
1016                 old_lock = ldlm_handle2lock(lockh);
1017                 LASSERT(old_lock);
1018
1019                 ns = old_lock->l_resource->lr_namespace;
1020                 res_id = &old_lock->l_resource->lr_name;
1021                 type = old_lock->l_resource->lr_type;
1022                 mode = old_lock->l_req_mode;
1023         }
1024
1025         res = ldlm_resource_get(ns, NULL, res_id, type, 0);
1026         if (res == NULL) {
1027                 LASSERT(old_lock == NULL);
1028                 RETURN(0);
1029         }
1030
1031         lock_res(res);
1032
1033         lock = search_queue(&res->lr_granted, &mode, policy, old_lock, flags);
1034         if (lock != NULL)
1035                 GOTO(out, rc = 1);
1036         if (flags & LDLM_FL_BLOCK_GRANTED)
1037                 GOTO(out, rc = 0);
1038         lock = search_queue(&res->lr_converting, &mode, policy, old_lock, flags);
1039         if (lock != NULL)
1040                 GOTO(out, rc = 1);
1041         lock = search_queue(&res->lr_waiting, &mode, policy, old_lock, flags);
1042         if (lock != NULL)
1043                 GOTO(out, rc = 1);
1044
1045         EXIT;
1046  out:
1047         unlock_res(res);
1048         ldlm_resource_putref(res);
1049
1050         if (lock) {
1051                 ldlm_lock2handle(lock, lockh);
1052                 if ((flags & LDLM_FL_LVB_READY) &&
1053                     (!(lock->l_flags & LDLM_FL_LVB_READY))) {
1054                         struct l_wait_info lwi;
1055                         if (lock->l_completion_ast) {
1056                                 int err = lock->l_completion_ast(lock,
1057                                                           LDLM_FL_WAIT_NOREPROC,
1058                                                                  NULL);
1059                                 if (err) {
1060                                         if (flags & LDLM_FL_TEST_LOCK)
1061                                                 LDLM_LOCK_PUT(lock);
1062                                         else
1063                                                 ldlm_lock_decref_internal(lock, mode);
1064                                         rc = 0;
1065                                         goto out2;
1066                                 }
1067                         }
1068
1069                         lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(obd_timeout), NULL,
1070                                                LWI_ON_SIGNAL_NOOP, NULL);
1071
1072                         /* XXX FIXME see comment on CAN_MATCH in lustre_dlm.h */
1073                         l_wait_event(lock->l_waitq,
1074                                      (lock->l_flags & LDLM_FL_LVB_READY), &lwi);
1075                 }
1076         }
1077  out2:
1078         if (rc) {
1079                 LDLM_DEBUG(lock, "matched ("LPU64" "LPU64")",
1080                            (type == LDLM_PLAIN || type == LDLM_IBITS) ?
1081                                 res_id->name[2] : policy->l_extent.start,
1082                            (type == LDLM_PLAIN || type == LDLM_IBITS) ?
1083                                 res_id->name[3] : policy->l_extent.end);
1084
1085                 /* check user's security context */
1086                 if (lock->l_conn_export &&
1087                     sptlrpc_import_check_ctx(
1088                                 class_exp2cliimp(lock->l_conn_export))) {
1089                         if (!(flags & LDLM_FL_TEST_LOCK))
1090                                 ldlm_lock_decref_internal(lock, mode);
1091                         rc = 0;
1092                 }
1093
1094                 if (flags & LDLM_FL_TEST_LOCK)
1095                         LDLM_LOCK_PUT(lock);
1096
1097         } else if (!(flags & LDLM_FL_TEST_LOCK)) {/*less verbose for test-only*/
1098                 LDLM_DEBUG_NOLOCK("not matched ns %p type %u mode %u res "
1099                                   LPU64"/"LPU64" ("LPU64" "LPU64")", ns,
1100                                   type, mode, res_id->name[0], res_id->name[1],
1101                                   (type == LDLM_PLAIN || type == LDLM_IBITS) ?
1102                                         res_id->name[2] :policy->l_extent.start,
1103                                 (type == LDLM_PLAIN || type == LDLM_IBITS) ?
1104                                         res_id->name[3] : policy->l_extent.end);
1105         }
1106         if (old_lock)
1107                 LDLM_LOCK_PUT(old_lock);
1108
1109         return rc ? mode : 0;
1110 }
1111
1112 /* Returns a referenced lock */
1113 struct ldlm_lock *ldlm_lock_create(struct ldlm_namespace *ns,
1114                                    const struct ldlm_res_id *res_id,
1115                                    ldlm_type_t type,
1116                                    ldlm_mode_t mode,
1117                                    ldlm_blocking_callback blocking,
1118                                    ldlm_completion_callback completion,
1119                                    ldlm_glimpse_callback glimpse,
1120                                    void *data, __u32 lvb_len)
1121 {
1122         struct ldlm_lock *lock;
1123         struct ldlm_resource *res;
1124         ENTRY;
1125
1126         res = ldlm_resource_get(ns, NULL, res_id, type, 1);
1127         if (res == NULL)
1128                 RETURN(NULL);
1129
1130         lock = ldlm_lock_new(res);
1131         ldlm_resource_putref(res);
1132
1133         if (lock == NULL)
1134                 RETURN(NULL);
1135
1136         lock->l_req_mode = mode;
1137         lock->l_ast_data = data;
1138         lock->l_blocking_ast = blocking;
1139         lock->l_completion_ast = completion;
1140         lock->l_glimpse_ast = glimpse;
1141         lock->l_pid = cfs_curproc_pid();
1142
1143         lock->l_tree_node = NULL;
1144         /* if this is the extent lock, allocate the interval tree node */
1145         if (type == LDLM_EXTENT) {
1146                 if (ldlm_interval_alloc(lock) == NULL)
1147                         GOTO(out, 0);
1148         }
1149
1150         if (lvb_len) {
1151                 lock->l_lvb_len = lvb_len;
1152                 OBD_ALLOC(lock->l_lvb_data, lvb_len);
1153                 if (lock->l_lvb_data == NULL)
1154                         GOTO(out, 0);
1155         }
1156
1157         RETURN(lock);
1158
1159 out:
1160         if (lock->l_lvb_data)
1161                 OBD_FREE(lock->l_lvb_data, lvb_len);
1162         ldlm_interval_free(ldlm_interval_detach(lock));
1163         OBD_SLAB_FREE(lock, ldlm_lock_slab, sizeof(*lock));
1164         return NULL;
1165 }
1166
1167 ldlm_error_t ldlm_lock_enqueue(struct ldlm_namespace *ns,
1168                                struct ldlm_lock **lockp,
1169                                void *cookie, int *flags)
1170 {
1171         struct ldlm_lock *lock = *lockp;
1172         struct ldlm_resource *res = lock->l_resource;
1173         int local = ns_is_client(res->lr_namespace);
1174         ldlm_processing_policy policy;
1175         ldlm_error_t rc = ELDLM_OK;
1176         struct ldlm_interval *node = NULL;
1177         ENTRY;
1178
1179         do_gettimeofday(&lock->l_enqueued_time);
1180         /* policies are not executed on the client or during replay */
1181         if ((*flags & (LDLM_FL_HAS_INTENT|LDLM_FL_REPLAY)) == LDLM_FL_HAS_INTENT
1182             && !local && ns->ns_policy) {
1183                 rc = ns->ns_policy(ns, lockp, cookie, lock->l_req_mode, *flags,
1184                                    NULL);
1185                 if (rc == ELDLM_LOCK_REPLACED) {
1186                         /* The lock that was returned has already been granted,
1187                          * and placed into lockp.  If it's not the same as the
1188                          * one we passed in, then destroy the old one and our
1189                          * work here is done. */
1190                         if (lock != *lockp) {
1191                                 ldlm_lock_destroy(lock);
1192                                 LDLM_LOCK_PUT(lock);
1193                         }
1194                         *flags |= LDLM_FL_LOCK_CHANGED;
1195                         RETURN(0);
1196                 } else if (rc != ELDLM_OK ||
1197                            (rc == ELDLM_OK && (*flags & LDLM_FL_INTENT_ONLY))) {
1198                         ldlm_lock_destroy(lock);
1199                         RETURN(rc);
1200                 }
1201         }
1202
1203         /* For a replaying lock, it might be already in granted list. So
1204          * unlinking the lock will cause the interval node to be freed, we
1205          * have to allocate the interval node early otherwise we can't regrant
1206          * this lock in the future. - jay */
1207         if (!local && (*flags & LDLM_FL_REPLAY) && res->lr_type == LDLM_EXTENT)
1208                 OBD_SLAB_ALLOC(node, ldlm_interval_slab, CFS_ALLOC_IO,
1209                                sizeof(*node));
1210
1211         lock_res_and_lock(lock);
1212         if (local && lock->l_req_mode == lock->l_granted_mode) {
1213                 /* The server returned a blocked lock, but it was granted
1214                  * before we got a chance to actually enqueue it.  We don't
1215                  * need to do anything else. */
1216                 *flags &= ~(LDLM_FL_BLOCK_GRANTED |
1217                             LDLM_FL_BLOCK_CONV | LDLM_FL_BLOCK_WAIT);
1218                 GOTO(out, ELDLM_OK);
1219         }
1220
1221         ldlm_resource_unlink_lock(lock);
1222         if (res->lr_type == LDLM_EXTENT && lock->l_tree_node == NULL) {
1223                 if (node == NULL) {
1224                         ldlm_lock_destroy_nolock(lock);
1225                         GOTO(out, rc = -ENOMEM);
1226                 }
1227
1228                 CFS_INIT_LIST_HEAD(&node->li_group);
1229                 ldlm_interval_attach(node, lock);
1230                 node = NULL;
1231         }
1232
1233         /* Some flags from the enqueue want to make it into the AST, via the
1234          * lock's l_flags. */
1235         lock->l_flags |= *flags & LDLM_AST_DISCARD_DATA;
1236
1237         /* This distinction between local lock trees is very important; a client
1238          * namespace only has information about locks taken by that client, and
1239          * thus doesn't have enough information to decide for itself if it can
1240          * be granted (below).  In this case, we do exactly what the server
1241          * tells us to do, as dictated by the 'flags'.
1242          *
1243          * We do exactly the same thing during recovery, when the server is
1244          * more or less trusting the clients not to lie.
1245          *
1246          * FIXME (bug 268): Detect obvious lies by checking compatibility in
1247          * granted/converting queues. */
1248         if (local) {
1249                 if (*flags & LDLM_FL_BLOCK_CONV)
1250                         ldlm_resource_add_lock(res, &res->lr_converting, lock);
1251                 else if (*flags & (LDLM_FL_BLOCK_WAIT | LDLM_FL_BLOCK_GRANTED))
1252                         ldlm_resource_add_lock(res, &res->lr_waiting, lock);
1253                 else
1254                         ldlm_grant_lock(lock, NULL);
1255                 GOTO(out, ELDLM_OK);
1256         } else if (*flags & LDLM_FL_REPLAY) {
1257                 if (*flags & LDLM_FL_BLOCK_CONV) {
1258                         ldlm_resource_add_lock(res, &res->lr_converting, lock);
1259                         GOTO(out, ELDLM_OK);
1260                 } else if (*flags & LDLM_FL_BLOCK_WAIT) {
1261                         ldlm_resource_add_lock(res, &res->lr_waiting, lock);
1262                         GOTO(out, ELDLM_OK);
1263                 } else if (*flags & LDLM_FL_BLOCK_GRANTED) {
1264                         ldlm_grant_lock(lock, NULL);
1265                         GOTO(out, ELDLM_OK);
1266                 }
1267                 /* If no flags, fall through to normal enqueue path. */
1268         }
1269
1270         policy = ldlm_processing_policy_table[res->lr_type];
1271         policy(lock, flags, 1, &rc, NULL);
1272         GOTO(out, rc);
1273 out:
1274         unlock_res_and_lock(lock);
1275         if (node)
1276                 OBD_SLAB_FREE(node, ldlm_interval_slab, sizeof(*node));
1277         return rc;
1278 }
1279
1280 /* Must be called with namespace taken: queue is waiting or converting. */
1281 int ldlm_reprocess_queue(struct ldlm_resource *res, struct list_head *queue,
1282                          struct list_head *work_list)
1283 {
1284         struct list_head *tmp, *pos;
1285         ldlm_processing_policy policy;
1286         int flags;
1287         int rc = LDLM_ITER_CONTINUE;
1288         ldlm_error_t err;
1289         ENTRY;
1290
1291         check_res_locked(res);
1292
1293         policy = ldlm_processing_policy_table[res->lr_type];
1294         LASSERT(policy);
1295
1296         list_for_each_safe(tmp, pos, queue) {
1297                 struct ldlm_lock *pending;
1298                 pending = list_entry(tmp, struct ldlm_lock, l_res_link);
1299
1300                 CDEBUG(D_INFO, "Reprocessing lock %p\n", pending);
1301
1302                 flags = 0;
1303                 rc = policy(pending, &flags, 0, &err, work_list);
1304                 if (rc != LDLM_ITER_CONTINUE)
1305                         break;
1306         }
1307
1308         RETURN(rc);
1309 }
1310
1311 /* Helper function for ldlm_run_ast_work().
1312  *
1313  * Send an existing rpc set specified by @arg->set and then
1314  * destroy it. Create new one if @do_create flag is set. */
1315 static void
1316 ldlm_send_and_maybe_create_set(struct ldlm_cb_set_arg *arg, int do_create)
1317 {
1318         ENTRY;
1319
1320         ptlrpc_set_wait(arg->set);
1321         if (arg->type == LDLM_BL_CALLBACK)
1322                 OBD_FAIL_TIMEOUT(OBD_FAIL_LDLM_GLIMPSE, 2);
1323         ptlrpc_set_destroy(arg->set);
1324
1325         if (do_create)
1326                 arg->set = ptlrpc_prep_set();
1327
1328         EXIT;
1329 }
1330
1331 static int
1332 ldlm_work_bl_ast_lock(struct list_head *tmp, struct ldlm_cb_set_arg *arg)
1333 {
1334         struct ldlm_lock_desc d;
1335         struct ldlm_lock *lock = list_entry(tmp, struct ldlm_lock, l_bl_ast);
1336         ENTRY;
1337
1338         /* nobody should touch l_bl_ast */
1339         lock_res_and_lock(lock);
1340         list_del_init(&lock->l_bl_ast);
1341
1342         LASSERT(lock->l_flags & LDLM_FL_AST_SENT);
1343         LASSERT(lock->l_bl_ast_run == 0);
1344         LASSERT(lock->l_blocking_lock);
1345         lock->l_bl_ast_run++;
1346         unlock_res_and_lock(lock);
1347
1348         ldlm_lock2desc(lock->l_blocking_lock, &d);
1349
1350         LDLM_LOCK_PUT(lock->l_blocking_lock);
1351         lock->l_blocking_lock = NULL;
1352         lock->l_blocking_ast(lock, &d, (void *)arg,
1353                              LDLM_CB_BLOCKING);
1354         LDLM_LOCK_PUT(lock);
1355
1356         RETURN(1);
1357 }
1358
1359 static int
1360 ldlm_work_cp_ast_lock(struct list_head *tmp, struct ldlm_cb_set_arg *arg)
1361 {
1362         struct ldlm_lock *lock = list_entry(tmp, struct ldlm_lock, l_cp_ast);
1363         ldlm_completion_callback completion_callback;
1364         int rc = 0;
1365         ENTRY;
1366
1367         /* It's possible to receive a completion AST before we've set
1368          * the l_completion_ast pointer: either because the AST arrived
1369          * before the reply, or simply because there's a small race
1370          * window between receiving the reply and finishing the local
1371          * enqueue. (bug 842)
1372          *
1373          * This can't happen with the blocking_ast, however, because we
1374          * will never call the local blocking_ast until we drop our
1375          * reader/writer reference, which we won't do until we get the
1376          * reply and finish enqueueing. */
1377
1378         /* nobody should touch l_cp_ast */
1379         lock_res_and_lock(lock);
1380         list_del_init(&lock->l_cp_ast);
1381         LASSERT(lock->l_flags & LDLM_FL_CP_REQD);
1382         /* save l_completion_ast since it can be changed by
1383          * mds_intent_policy(), see bug 14225 */
1384         completion_callback = lock->l_completion_ast;
1385         lock->l_flags &= ~LDLM_FL_CP_REQD;
1386         unlock_res_and_lock(lock);
1387
1388         if (completion_callback != NULL) {
1389                 completion_callback(lock, 0, (void *)arg);
1390                 rc = 1;
1391         }
1392         LDLM_LOCK_PUT(lock);
1393
1394         RETURN(rc);
1395 }
1396
1397 static int
1398 ldlm_work_revoke_ast_lock(struct list_head *tmp, struct ldlm_cb_set_arg *arg)
1399 {
1400         struct ldlm_lock_desc desc;
1401         struct ldlm_lock *lock = list_entry(tmp, struct ldlm_lock, l_export_chain);
1402         ENTRY;
1403
1404         list_del_init(&lock->l_export_chain);
1405
1406         /* the desc just pretend to exclusive */
1407         ldlm_lock2desc(lock, &desc);
1408         desc.l_req_mode = LCK_EX;
1409         desc.l_granted_mode = 0;
1410
1411         lock->l_blocking_ast(lock, &desc, (void*)arg, LDLM_CB_BLOCKING);
1412         LDLM_LOCK_PUT(lock);
1413
1414         RETURN(1);
1415 }
1416
1417 int ldlm_run_ast_work(struct list_head *rpc_list, ldlm_desc_ast_t ast_type)
1418 {
1419         struct ldlm_cb_set_arg arg;
1420         struct list_head *tmp, *pos;
1421         int (*work_ast_lock)(struct list_head *tmp, struct ldlm_cb_set_arg *arg);
1422         int ast_count;
1423         ENTRY;
1424
1425         arg.set = ptlrpc_prep_set();
1426         atomic_set(&arg.restart, 0);
1427         switch (ast_type) {
1428         case LDLM_WORK_BL_AST:
1429                 arg.type = LDLM_BL_CALLBACK;
1430                 work_ast_lock = ldlm_work_bl_ast_lock;
1431                 break;
1432         case LDLM_WORK_CP_AST:
1433                 arg.type = LDLM_CP_CALLBACK;
1434                 work_ast_lock = ldlm_work_cp_ast_lock;
1435                 break;
1436         case LDLM_WORK_REVOKE_AST:
1437                 arg.type = LDLM_BL_CALLBACK;
1438                 work_ast_lock = ldlm_work_revoke_ast_lock;
1439                 break;
1440         default:
1441                 LBUG();
1442         }
1443
1444         ast_count = 0;
1445         list_for_each_safe(tmp, pos, rpc_list) {
1446                 ast_count += work_ast_lock(tmp, &arg);
1447
1448                 /* Send the request set if it exceeds the PARALLEL_AST_LIMIT,
1449                  * and create a new set for requests that remained in
1450                  * @rpc_list */
1451                 if (unlikely(ast_count == PARALLEL_AST_LIMIT)) {
1452                         ldlm_send_and_maybe_create_set(&arg, 1);
1453                         ast_count = 0;
1454                 }
1455         }
1456
1457         if (ast_count > 0)
1458                 ldlm_send_and_maybe_create_set(&arg, 0);
1459         else
1460                 /* In case when number of ASTs is multiply of
1461                  * PARALLEL_AST_LIMIT or @rpc_list was initially empty,
1462                  * @arg.set must be destroyed here, otherwise we get
1463                  * write memory leaking. */
1464                 ptlrpc_set_destroy(arg.set);
1465
1466         RETURN(atomic_read(&arg.restart) ? -ERESTART : 0);
1467 }
1468
1469 static int reprocess_one_queue(struct ldlm_resource *res, void *closure)
1470 {
1471         ldlm_reprocess_all(res);
1472         return LDLM_ITER_CONTINUE;
1473 }
1474
1475 void ldlm_reprocess_all_ns(struct ldlm_namespace *ns)
1476 {
1477         struct list_head *tmp;
1478         int i, rc;
1479
1480         if (ns == NULL)
1481                 return;
1482
1483         ENTRY;
1484         spin_lock(&ns->ns_hash_lock);
1485         for (i = 0; i < RES_HASH_SIZE; i++) {
1486                 tmp = ns->ns_hash[i].next;
1487                 while (tmp != &(ns->ns_hash[i])) {
1488                         struct ldlm_resource *res =
1489                                 list_entry(tmp, struct ldlm_resource, lr_hash);
1490
1491                         ldlm_resource_getref(res);
1492                         spin_unlock(&ns->ns_hash_lock);
1493
1494                         rc = reprocess_one_queue(res, NULL);
1495
1496                         spin_lock(&ns->ns_hash_lock);
1497                         tmp = tmp->next;
1498                         ldlm_resource_putref_locked(res);
1499
1500                         if (rc == LDLM_ITER_STOP)
1501                                 GOTO(out, rc);
1502                 }
1503         }
1504  out:
1505         spin_unlock(&ns->ns_hash_lock);
1506         EXIT;
1507 }
1508
1509 void ldlm_reprocess_all(struct ldlm_resource *res)
1510 {
1511         struct list_head rpc_list = LIST_HEAD_INIT(rpc_list);
1512         int rc;
1513         ENTRY;
1514
1515         /* Local lock trees don't get reprocessed. */
1516         if (ns_is_client(res->lr_namespace)) {
1517                 EXIT;
1518                 return;
1519         }
1520
1521  restart:
1522         lock_res(res);
1523         rc = ldlm_reprocess_queue(res, &res->lr_converting, &rpc_list);
1524         if (rc == LDLM_ITER_CONTINUE)
1525                 ldlm_reprocess_queue(res, &res->lr_waiting, &rpc_list);
1526         unlock_res(res);
1527
1528         rc = ldlm_run_ast_work(&rpc_list, LDLM_WORK_CP_AST);
1529         if (rc == -ERESTART) {
1530                 LASSERT(list_empty(&rpc_list));
1531                 goto restart;
1532         }
1533         EXIT;
1534 }
1535
1536 void ldlm_cancel_callback(struct ldlm_lock *lock)
1537 {
1538         check_res_locked(lock->l_resource);
1539         if (!(lock->l_flags & LDLM_FL_CANCEL)) {
1540                 lock->l_flags |= LDLM_FL_CANCEL;
1541                 if (lock->l_blocking_ast) {
1542                         // l_check_no_ns_lock(ns);
1543                         unlock_res_and_lock(lock);
1544                         lock->l_blocking_ast(lock, NULL, lock->l_ast_data,
1545                                              LDLM_CB_CANCELING);
1546                         lock_res_and_lock(lock);
1547                 } else {
1548                         LDLM_DEBUG(lock, "no blocking ast");
1549                 }
1550         }
1551         lock->l_flags |= LDLM_FL_BL_DONE;
1552 }
1553
1554 void ldlm_unlink_lock_skiplist(struct ldlm_lock *req)
1555 {
1556         struct ldlm_lock *lock;
1557
1558         if (req->l_resource->lr_type != LDLM_PLAIN &&
1559             req->l_resource->lr_type != LDLM_IBITS)
1560                 return;
1561
1562         if (LDLM_SL_HEAD(&req->l_sl_mode)) {
1563                 lock = list_entry(req->l_res_link.next, struct ldlm_lock,
1564                                   l_res_link);
1565                 if (req->l_sl_mode.next == &lock->l_sl_mode) {
1566                         lock->l_sl_mode.prev = NULL;
1567                 } else {
1568                         lock->l_sl_mode.next = req->l_sl_mode.next;
1569                         lock->l_sl_mode.next->prev = &lock->l_sl_mode;
1570                 }
1571                 req->l_sl_mode.next = NULL;
1572         } else if (LDLM_SL_TAIL(&req->l_sl_mode)) {
1573                 lock = list_entry(req->l_res_link.prev, struct ldlm_lock,
1574                                   l_res_link);
1575                 if (req->l_sl_mode.prev == &lock->l_sl_mode) {
1576                         lock->l_sl_mode.next = NULL;
1577                 } else {
1578                         lock->l_sl_mode.prev = req->l_sl_mode.prev;
1579                         lock->l_sl_mode.prev->next = &lock->l_sl_mode;
1580                 }
1581                 req->l_sl_mode.prev = NULL;
1582         }
1583
1584         if (LDLM_SL_HEAD(&req->l_sl_policy)) {
1585                 lock = list_entry(req->l_res_link.next, struct ldlm_lock,
1586                                   l_res_link);
1587                 if (req->l_sl_policy.next == &lock->l_sl_policy) {
1588                         lock->l_sl_policy.prev = NULL;
1589                 } else {
1590                         lock->l_sl_policy.next = req->l_sl_policy.next;
1591                         lock->l_sl_policy.next->prev = &lock->l_sl_policy;
1592                 }
1593                 req->l_sl_policy.next = NULL;
1594         } else if (LDLM_SL_TAIL(&req->l_sl_policy)) {
1595                 lock = list_entry(req->l_res_link.prev, struct ldlm_lock,
1596                                   l_res_link);
1597                 if (req->l_sl_policy.prev == &lock->l_sl_policy) {
1598                         lock->l_sl_policy.next = NULL;
1599                 } else {
1600                         lock->l_sl_policy.prev = req->l_sl_policy.prev;
1601                         lock->l_sl_policy.prev->next = &lock->l_sl_policy;
1602                 }
1603                 req->l_sl_policy.prev = NULL;
1604         }
1605 }
1606
1607 void ldlm_lock_cancel(struct ldlm_lock *lock)
1608 {
1609         struct ldlm_resource *res;
1610         struct ldlm_namespace *ns;
1611         ENTRY;
1612
1613         lock_res_and_lock(lock);
1614
1615         res = lock->l_resource;
1616         ns = res->lr_namespace;
1617
1618         /* Please do not, no matter how tempting, remove this LBUG without
1619          * talking to me first. -phik */
1620         if (lock->l_readers || lock->l_writers) {
1621                 LDLM_ERROR(lock, "lock still has references");
1622                 LBUG();
1623         }
1624
1625         ldlm_del_waiting_lock(lock);
1626
1627         /* Releases cancel callback. */
1628         ldlm_cancel_callback(lock);
1629
1630         /* Yes, second time, just in case it was added again while we were
1631            running with no res lock in ldlm_cancel_callback */
1632         ldlm_del_waiting_lock(lock);
1633         ldlm_resource_unlink_lock(lock);
1634         ldlm_lock_destroy_nolock(lock);
1635
1636         if (lock->l_granted_mode == lock->l_req_mode)
1637                 ldlm_pool_del(&ns->ns_pool, lock);
1638
1639         /* Make sure we will not be called again for same lock what is possible
1640          * if not to zero out lock->l_granted_mode */
1641         lock->l_granted_mode = 0;
1642         unlock_res_and_lock(lock);
1643
1644         EXIT;
1645 }
1646
1647 int ldlm_lock_set_data(struct lustre_handle *lockh, void *data)
1648 {
1649         struct ldlm_lock *lock = ldlm_handle2lock(lockh);
1650         ENTRY;
1651
1652         if (lock == NULL)
1653                 RETURN(-EINVAL);
1654
1655         lock->l_ast_data = data;
1656         LDLM_LOCK_PUT(lock);
1657         RETURN(0);
1658 }
1659
1660 void ldlm_cancel_locks_for_export(struct obd_export *exp)
1661 {
1662         struct ldlm_lock *lock;
1663         struct ldlm_resource *res;
1664
1665         spin_lock(&exp->exp_ldlm_data.led_lock);
1666         while(!list_empty(&exp->exp_ldlm_data.led_held_locks)) {
1667                 lock = list_entry(exp->exp_ldlm_data.led_held_locks.next,
1668                                   struct ldlm_lock, l_export_chain);
1669                 res = ldlm_resource_getref(lock->l_resource);
1670                 LDLM_LOCK_GET(lock);
1671                 spin_unlock(&exp->exp_ldlm_data.led_lock);
1672
1673                 LDLM_DEBUG(lock, "export %p", exp);
1674                 ldlm_res_lvbo_update(res, NULL, 0, 1);
1675
1676                 ldlm_lock_cancel(lock);
1677                 ldlm_reprocess_all(res);
1678
1679                 ldlm_resource_putref(res);
1680                 LDLM_LOCK_PUT(lock);
1681                 spin_lock(&exp->exp_ldlm_data.led_lock);
1682         }
1683         spin_unlock(&exp->exp_ldlm_data.led_lock);
1684 }
1685
1686 struct ldlm_resource *ldlm_lock_convert(struct ldlm_lock *lock, int new_mode,
1687                                         __u32 *flags)
1688 {
1689         struct list_head rpc_list = LIST_HEAD_INIT(rpc_list);
1690         struct ldlm_resource *res;
1691         struct ldlm_namespace *ns;
1692         int granted = 0;
1693         int old_mode, rc;
1694         struct ldlm_lock *mark_lock = NULL;
1695         int join = LDLM_JOIN_NONE;
1696         ldlm_error_t err;
1697         struct ldlm_interval *node;
1698         ENTRY;
1699
1700         if (new_mode == lock->l_granted_mode) { // No changes? Just return.
1701                 *flags |= LDLM_FL_BLOCK_GRANTED;
1702                 RETURN(lock->l_resource);
1703         }
1704
1705         /* I can't check the type of lock here because the bitlock of lock
1706          * is not held here, so do the allocation blindly. -jay */
1707         OBD_SLAB_ALLOC(node, ldlm_interval_slab, CFS_ALLOC_IO, sizeof(*node));
1708         if (node == NULL)  /* Actually, this causes EDEADLOCK to be returned */
1709                 RETURN(NULL);
1710
1711         LASSERTF(new_mode == LCK_PW && lock->l_granted_mode == LCK_PR,
1712                  "new_mode %u, granted %u\n", new_mode, lock->l_granted_mode);
1713
1714         lock_res_and_lock(lock);
1715
1716         res = lock->l_resource;
1717         ns = res->lr_namespace;
1718
1719         old_mode = lock->l_req_mode;
1720         lock->l_req_mode = new_mode;
1721         if (res->lr_type == LDLM_PLAIN || res->lr_type == LDLM_IBITS) {
1722                 /* remember the lock position where the lock might be
1723                  * added back to the granted list later and also
1724                  * remember the join mode for skiplist fixing. */
1725                 if (LDLM_SL_HEAD(&lock->l_sl_mode))
1726                         join = LDLM_MODE_JOIN_RIGHT;
1727                 else if (LDLM_SL_TAIL(&lock->l_sl_mode))
1728                         join = LDLM_MODE_JOIN_LEFT;
1729                 if (LDLM_SL_HEAD(&lock->l_sl_policy))
1730                         join |= LDLM_POLICY_JOIN_RIGHT;
1731                 else if (LDLM_SL_TAIL(&lock->l_sl_policy))
1732                         join |= LDLM_POLICY_JOIN_LEFT;
1733
1734                 LASSERT(!((join & LDLM_MODE_JOIN_RIGHT) &&
1735                           (join & LDLM_POLICY_JOIN_LEFT)));
1736                 LASSERT(!((join & LDLM_MODE_JOIN_LEFT) &&
1737                           (join & LDLM_POLICY_JOIN_RIGHT)));
1738
1739                 if ((join & LDLM_MODE_JOIN_LEFT) ||
1740                     (join & LDLM_POLICY_JOIN_LEFT))
1741                         mark_lock = list_entry(lock->l_res_link.prev,
1742                                                struct ldlm_lock, l_res_link);
1743                 else if (lock->l_res_link.next != &res->lr_granted)
1744                         mark_lock = list_entry(lock->l_res_link.next,
1745                                                struct ldlm_lock, l_res_link);
1746         } else {
1747                 ldlm_resource_unlink_lock(lock);
1748                 if (res->lr_type == LDLM_EXTENT) {
1749                         /* FIXME: ugly code, I have to attach the lock to a
1750                          * interval node again since perhaps it will be granted
1751                          * soon */
1752                         CFS_INIT_LIST_HEAD(&node->li_group);
1753                         ldlm_interval_attach(node, lock);
1754                         node = NULL;
1755                 }
1756         }
1757
1758         /* If this is a local resource, put it on the appropriate list. */
1759         if (ns_is_client(res->lr_namespace)) {
1760                 if (*flags & (LDLM_FL_BLOCK_CONV | LDLM_FL_BLOCK_GRANTED)) {
1761                         ldlm_resource_add_lock(res, &res->lr_converting, lock);
1762                 } else {
1763                         /* This should never happen, because of the way the
1764                          * server handles conversions. */
1765                         LDLM_ERROR(lock, "Erroneous flags %d on local lock\n",
1766                                    *flags);
1767                         LBUG();
1768
1769                         ldlm_grant_lock(lock, &rpc_list);
1770                         granted = 1;
1771                         /* FIXME: completion handling not with ns_lock held ! */
1772                         if (lock->l_completion_ast)
1773                                 lock->l_completion_ast(lock, 0, NULL);
1774                 }
1775         } else {
1776                 int pflags = 0;
1777                 ldlm_processing_policy policy;
1778                 policy = ldlm_processing_policy_table[res->lr_type];
1779                 rc = policy(lock, &pflags, 0, &err, &rpc_list);
1780                 if (rc == LDLM_ITER_STOP) {
1781                         lock->l_req_mode = old_mode;
1782                         if (res->lr_type == LDLM_EXTENT)
1783                                 ldlm_extent_add_lock(res, lock);
1784                         else
1785                                 ldlm_granted_list_add_lock(lock, mark_lock,
1786                                                            join);
1787                         res = NULL;
1788                 } else {
1789                         *flags |= LDLM_FL_BLOCK_GRANTED;
1790                         granted = 1;
1791                 }
1792         }
1793         unlock_res_and_lock(lock);
1794
1795         if (granted)
1796                 ldlm_run_ast_work(&rpc_list, LDLM_WORK_CP_AST);
1797         if (node)
1798                 OBD_SLAB_FREE(node, ldlm_interval_slab, sizeof(*node));
1799         RETURN(res);
1800 }
1801
1802 void ldlm_lock_dump(int level, struct ldlm_lock *lock, int pos)
1803 {
1804         struct obd_device *obd = NULL;
1805
1806         if (!((libcfs_debug | D_ERROR) & level))
1807                 return;
1808
1809         if (!lock) {
1810                 CDEBUG(level, "  NULL LDLM lock\n");
1811                 return;
1812         }
1813
1814         CDEBUG(level," -- Lock dump: %p/"LPX64" (rc: %d) (pos: %d) (pid: %d)\n",
1815                lock, lock->l_handle.h_cookie, atomic_read(&lock->l_refc),
1816                pos, lock->l_pid);
1817         if (lock->l_conn_export != NULL)
1818                 obd = lock->l_conn_export->exp_obd;
1819         if (lock->l_export && lock->l_export->exp_connection) {
1820                 CDEBUG(level, "  Node: NID %s (rhandle: "LPX64")\n",
1821                      libcfs_nid2str(lock->l_export->exp_connection->c_peer.nid),
1822                      lock->l_remote_handle.cookie);
1823         } else if (obd == NULL) {
1824                 CDEBUG(level, "  Node: local\n");
1825         } else {
1826                 struct obd_import *imp = obd->u.cli.cl_import;
1827                 CDEBUG(level, "  Node: NID %s (rhandle: "LPX64")\n",
1828                        libcfs_nid2str(imp->imp_connection->c_peer.nid),
1829                        lock->l_remote_handle.cookie);
1830         }
1831         CDEBUG(level, "  Resource: %p ("LPU64"/"LPU64"/"LPU64")\n",
1832                   lock->l_resource,
1833                   lock->l_resource->lr_name.name[0],
1834                   lock->l_resource->lr_name.name[1],
1835                   lock->l_resource->lr_name.name[2]);
1836         CDEBUG(level, "  Req mode: %s, grant mode: %s, rc: %u, read: %d, "
1837                "write: %d flags: %#x\n", ldlm_lockname[lock->l_req_mode],
1838                ldlm_lockname[lock->l_granted_mode],
1839                atomic_read(&lock->l_refc), lock->l_readers, lock->l_writers,
1840                lock->l_flags);
1841         if (lock->l_resource->lr_type == LDLM_EXTENT)
1842                 CDEBUG(level, "  Extent: "LPU64" -> "LPU64
1843                        " (req "LPU64"-"LPU64")\n",
1844                        lock->l_policy_data.l_extent.start,
1845                        lock->l_policy_data.l_extent.end,
1846                        lock->l_req_extent.start, lock->l_req_extent.end);
1847         else if (lock->l_resource->lr_type == LDLM_FLOCK)
1848                 CDEBUG(level, "  Pid: %d Extent: "LPU64" -> "LPU64"\n",
1849                        lock->l_policy_data.l_flock.pid,
1850                        lock->l_policy_data.l_flock.start,
1851                        lock->l_policy_data.l_flock.end);
1852        else if (lock->l_resource->lr_type == LDLM_IBITS)
1853                 CDEBUG(level, "  Bits: "LPX64"\n",
1854                        lock->l_policy_data.l_inodebits.bits);
1855 }
1856
1857 void ldlm_lock_dump_handle(int level, struct lustre_handle *lockh)
1858 {
1859         struct ldlm_lock *lock;
1860
1861         if (!((libcfs_debug | D_ERROR) & level))
1862                 return;
1863
1864         lock = ldlm_handle2lock(lockh);
1865         if (lock == NULL)
1866                 return;
1867
1868         ldlm_lock_dump(D_OTHER, lock, 0);
1869
1870         LDLM_LOCK_PUT(lock);
1871 }
1872
1873 void _ldlm_lock_debug(struct ldlm_lock *lock, __u32 level,
1874                       struct libcfs_debug_msg_data *data, const char *fmt,
1875                       ...)
1876 {
1877         va_list args;
1878         cfs_debug_limit_state_t *cdls = data->msg_cdls;
1879
1880         va_start(args, fmt);
1881
1882         if (lock->l_resource == NULL) {
1883                 libcfs_debug_vmsg2(cdls, data->msg_subsys, level, data->msg_file,
1884                                    data->msg_fn, data->msg_line, fmt, args,
1885                        " ns: \?\? lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
1886                        "res: \?\? rrc=\?\? type: \?\?\? flags: %x remote: "
1887                        LPX64" expref: %d pid: %u\n", lock,
1888                        lock->l_handle.h_cookie, atomic_read(&lock->l_refc),
1889                        lock->l_readers, lock->l_writers,
1890                        ldlm_lockname[lock->l_granted_mode],
1891                        ldlm_lockname[lock->l_req_mode],
1892                        lock->l_flags, lock->l_remote_handle.cookie,
1893                        lock->l_export ?
1894                        atomic_read(&lock->l_export->exp_refcount) : -99,
1895                        lock->l_pid);
1896                 va_end(args);
1897                 return;
1898         }
1899
1900         switch (lock->l_resource->lr_type) {
1901         case LDLM_EXTENT:
1902                 libcfs_debug_vmsg2(cdls, data->msg_subsys, level, data->msg_file,
1903                                    data->msg_fn, data->msg_line, fmt, args,
1904                        " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
1905                        "res: "LPU64"/"LPU64" rrc: %d type: %s ["LPU64"->"LPU64
1906                        "] (req "LPU64"->"LPU64") flags: %x remote: "LPX64
1907                        " expref: %d pid: %u\n",
1908                        lock->l_resource->lr_namespace->ns_name, lock,
1909                        lock->l_handle.h_cookie, atomic_read(&lock->l_refc),
1910                        lock->l_readers, lock->l_writers,
1911                        ldlm_lockname[lock->l_granted_mode],
1912                        ldlm_lockname[lock->l_req_mode],
1913                        lock->l_resource->lr_name.name[0],
1914                        lock->l_resource->lr_name.name[1],
1915                        atomic_read(&lock->l_resource->lr_refcount),
1916                        ldlm_typename[lock->l_resource->lr_type],
1917                        lock->l_policy_data.l_extent.start,
1918                        lock->l_policy_data.l_extent.end,
1919                        lock->l_req_extent.start, lock->l_req_extent.end,
1920                        lock->l_flags, lock->l_remote_handle.cookie,
1921                        lock->l_export ?
1922                        atomic_read(&lock->l_export->exp_refcount) : -99,
1923                        lock->l_pid);
1924                 break;
1925
1926         case LDLM_FLOCK:
1927                 libcfs_debug_vmsg2(cdls, data->msg_subsys, level, data->msg_file,
1928                                    data->msg_fn, data->msg_line, fmt, args,
1929                        " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
1930                        "res: "LPU64"/"LPU64" rrc: %d type: %s pid: %d "
1931                        "["LPU64"->"LPU64"] flags: %x remote: "LPX64
1932                        " expref: %d pid: %u\n",
1933                        lock->l_resource->lr_namespace->ns_name, lock,
1934                        lock->l_handle.h_cookie, atomic_read(&lock->l_refc),
1935                        lock->l_readers, lock->l_writers,
1936                        ldlm_lockname[lock->l_granted_mode],
1937                        ldlm_lockname[lock->l_req_mode],
1938                        lock->l_resource->lr_name.name[0],
1939                        lock->l_resource->lr_name.name[1],
1940                        atomic_read(&lock->l_resource->lr_refcount),
1941                        ldlm_typename[lock->l_resource->lr_type],
1942                        lock->l_policy_data.l_flock.pid,
1943                        lock->l_policy_data.l_flock.start,
1944                        lock->l_policy_data.l_flock.end,
1945                        lock->l_flags, lock->l_remote_handle.cookie,
1946                        lock->l_export ?
1947                        atomic_read(&lock->l_export->exp_refcount) : -99,
1948                        lock->l_pid);
1949                 break;
1950
1951         case LDLM_IBITS:
1952                 libcfs_debug_vmsg2(cdls, data->msg_subsys, level, data->msg_file,
1953                                    data->msg_fn, data->msg_line, fmt, args,
1954                        " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
1955                        "res: "LPU64"/"LPU64" bits "LPX64" rrc: %d type: %s "
1956                        "flags: %x remote: "LPX64" expref: %d "
1957                        "pid %u\n",
1958                        lock->l_resource->lr_namespace->ns_name,
1959                        lock, lock->l_handle.h_cookie,
1960                        atomic_read (&lock->l_refc),
1961                        lock->l_readers, lock->l_writers,
1962                        ldlm_lockname[lock->l_granted_mode],
1963                        ldlm_lockname[lock->l_req_mode],
1964                        lock->l_resource->lr_name.name[0],
1965                        lock->l_resource->lr_name.name[1],
1966                        lock->l_policy_data.l_inodebits.bits,
1967                        atomic_read(&lock->l_resource->lr_refcount),
1968                        ldlm_typename[lock->l_resource->lr_type],
1969                        lock->l_flags, lock->l_remote_handle.cookie,
1970                        lock->l_export ?
1971                        atomic_read(&lock->l_export->exp_refcount) : -99,
1972                        lock->l_pid);
1973                 break;
1974
1975         default:
1976                 libcfs_debug_vmsg2(cdls, data->msg_subsys, level, data->msg_file,
1977                                    data->msg_fn, data->msg_line, fmt, args,
1978                        " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
1979                        "res: "LPU64"/"LPU64" rrc: %d type: %s flags: %x "
1980                        "remote: "LPX64" expref: %d pid: %u\n",
1981                        lock->l_resource->lr_namespace->ns_name,
1982                        lock, lock->l_handle.h_cookie,
1983                        atomic_read (&lock->l_refc),
1984                        lock->l_readers, lock->l_writers,
1985                        ldlm_lockname[lock->l_granted_mode],
1986                        ldlm_lockname[lock->l_req_mode],
1987                        lock->l_resource->lr_name.name[0],
1988                        lock->l_resource->lr_name.name[1],
1989                        atomic_read(&lock->l_resource->lr_refcount),
1990                        ldlm_typename[lock->l_resource->lr_type],
1991                        lock->l_flags, lock->l_remote_handle.cookie,
1992                        lock->l_export ?
1993                        atomic_read(&lock->l_export->exp_refcount) : -99,
1994                        lock->l_pid);
1995                 break;
1996         }
1997         va_end(args);
1998 }
1999 EXPORT_SYMBOL(_ldlm_lock_debug);