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  * GPL HEADER START
   5  *
   6  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 only,
  10  * as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License version 2 for more details (a copy is included
  16  * in the LICENSE file that accompanied this code).
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * version 2 along with this program; If not, see
  20  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  21  *
  22  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  23  * CA 95054 USA or visit www.sun.com if you need additional information or
  24  * have any questions.
  25  *
  26  * GPL HEADER END
  27  */
  28 /*
  29  * Copyright  2008 Sun Microsystems, Inc. All rights reserved
  30  * Use is subject to license terms.
  31  */
  32 /*
  33  * This file is part of Lustre, http://www.lustre.org/
  34  * Lustre is a trademark of Sun Microsystems, Inc.
  35  *
  36  * lustre/ldlm/ldlm_lock.c
  37  *
  38  * Author: Peter Braam <braam@clusterfs.com>
  39  * Author: Phil Schwan <phil@clusterfs.com>
  40  */
  41
  42 #define DEBUG_SUBSYSTEM S_LDLM
  43
  44 #ifdef __KERNEL__
  45 # include <libcfs/libcfs.h>
  46 # ifndef HAVE_VFS_INTENT_PATCHES
  47 # include <linux/lustre_intent.h>
  48 # endif
  49 #else
  50 # include <liblustre.h>
  51 #endif
  52
  53 #include <obd_class.h>
  54 #include "ldlm_internal.h"
  55
  56 /* lock types */
  57 char *ldlm_lockname[] = {
  58         [0] "--",
  59         [LCK_EX] "EX",
  60         [LCK_PW] "PW",
  61         [LCK_PR] "PR",
  62         [LCK_CW] "CW",
  63         [LCK_CR] "CR",
  64         [LCK_NL] "NL",
  65         [LCK_GROUP] "GROUP",
  66         [LCK_COS] "COS"
  67 };
  68
  69 char *ldlm_typename[] = {
  70         [LDLM_PLAIN] "PLN",
  71         [LDLM_EXTENT] "EXT",
  72         [LDLM_FLOCK] "FLK",
  73         [LDLM_IBITS] "IBT",
  74 };
  75
  76 char *ldlm_it2str(int it)
  77 {
  78         switch (it) {
  79         case IT_OPEN:
  80                 return "open";
  81         case IT_CREAT:
  82                 return "creat";
  83         case (IT_OPEN | IT_CREAT):
  84                 return "open|creat";
  85         case IT_READDIR:
  86                 return "readdir";
  87         case IT_GETATTR:
  88                 return "getattr";
  89         case IT_LOOKUP:
  90                 return "lookup";
  91         case IT_UNLINK:
  92                 return "unlink";
  93         case IT_GETXATTR:
  94                 return "getxattr";
  95         default:
  96                 CERROR("Unknown intent %d\n", it);
  97                 return "UNKNOWN";
  98         }
  99 }
 100
 101 extern cfs_mem_cache_t *ldlm_lock_slab;
 102
 103 static ldlm_processing_policy ldlm_processing_policy_table[] = {
 104         [LDLM_PLAIN] ldlm_process_plain_lock,
 105         [LDLM_EXTENT] ldlm_process_extent_lock,
 106 #ifdef __KERNEL__
 107         [LDLM_FLOCK] ldlm_process_flock_lock,
 108 #endif
 109         [LDLM_IBITS] ldlm_process_inodebits_lock,
 110 };
 111
 112 ldlm_processing_policy ldlm_get_processing_policy(struct ldlm_resource *res)
 113 {
 114         return ldlm_processing_policy_table[res->lr_type];
 115 }
 116
 117 void ldlm_register_intent(struct ldlm_namespace *ns, ldlm_res_policy arg)
 118 {
 119         ns->ns_policy = arg;
 120 }
 121
 122 /*
 123  * REFCOUNTED LOCK OBJECTS
 124  */
 125
 126
 127 /*
 128  * Lock refcounts, during creation:
 129  *   - one special one for allocation, dec'd only once in destroy
 130  *   - one for being a lock that's in-use
 131  *   - one for the addref associated with a new lock
 132  */
 133 struct ldlm_lock *ldlm_lock_get(struct ldlm_lock *lock)
 134 {
 135         atomic_inc(&lock->l_refc);
 136         return lock;
 137 }
 138
 139 static void ldlm_lock_free(struct ldlm_lock *lock, size_t size)
 140 {
 141         LASSERT(size == sizeof(*lock));
 142         OBD_SLAB_FREE(lock, ldlm_lock_slab, sizeof(*lock));
 143 }
 144
 145 void ldlm_lock_put(struct ldlm_lock *lock)
 146 {
 147         ENTRY;
 148
 149         LASSERT(lock->l_resource != LP_POISON);
 150         LASSERT(atomic_read(&lock->l_refc) > 0);
 151         if (atomic_dec_and_test(&lock->l_refc)) {
 152                 struct ldlm_resource *res;
 153
 154                 LDLM_DEBUG(lock,
 155                            "final lock_put on destroyed lock, freeing it.");
 156
 157                 res = lock->l_resource;
 158                 LASSERT(lock->l_destroyed);
 159                 LASSERT(list_empty(&lock->l_res_link));
 160                 LASSERT(list_empty(&lock->l_pending_chain));
 161
 162                 atomic_dec(&res->lr_namespace->ns_locks);
 163                 lu_ref_del(&res->lr_reference, "lock", lock);
 164                 ldlm_resource_putref(res);
 165                 lock->l_resource = NULL;
 166                 if (lock->l_export) {
 167                         class_export_put(lock->l_export);
 168                         lock->l_export = NULL;
 169                 }
 170
 171                 if (lock->l_lvb_data != NULL)
 172                         OBD_FREE(lock->l_lvb_data, lock->l_lvb_len);
 173
 174                 ldlm_interval_free(ldlm_interval_detach(lock));
 175                 lu_ref_fini(&lock->l_reference);
 176                 OBD_FREE_RCU_CB(lock, sizeof(*lock), &lock->l_handle,
 177                                 ldlm_lock_free);
 178         }
 179
 180         EXIT;
 181 }
 182
 183 int ldlm_lock_remove_from_lru_nolock(struct ldlm_lock *lock)
 184 {
 185         int rc = 0;
 186         if (!list_empty(&lock->l_lru)) {
 187                 struct ldlm_namespace *ns = lock->l_resource->lr_namespace;
 188                 LASSERT(lock->l_resource->lr_type != LDLM_FLOCK);
 189                 list_del_init(&lock->l_lru);
 190                 LASSERT(ns->ns_nr_unused > 0);
 191                 ns->ns_nr_unused--;
 192                 rc = 1;
 193         }
 194         return rc;
 195 }
 196
 197 int ldlm_lock_remove_from_lru(struct ldlm_lock *lock)
 198 {
 199         struct ldlm_namespace *ns = lock->l_resource->lr_namespace;
 200         int rc;
 201         ENTRY;
 202         spin_lock(&ns->ns_unused_lock);
 203         rc = ldlm_lock_remove_from_lru_nolock(lock);
 204         spin_unlock(&ns->ns_unused_lock);
 205         EXIT;
 206         return rc;
 207 }
 208
 209 void ldlm_lock_add_to_lru_nolock(struct ldlm_lock *lock)
 210 {
 211         struct ldlm_namespace *ns = lock->l_resource->lr_namespace;
 212         lock->l_last_used = cfs_time_current();
 213         LASSERT(list_empty(&lock->l_lru));
 214         LASSERT(lock->l_resource->lr_type != LDLM_FLOCK);
 215         list_add_tail(&lock->l_lru, &ns->ns_unused_list);
 216         LASSERT(ns->ns_nr_unused >= 0);
 217         ns->ns_nr_unused++;
 218 }
 219
 220 void ldlm_lock_add_to_lru(struct ldlm_lock *lock)
 221 {
 222         struct ldlm_namespace *ns = lock->l_resource->lr_namespace;
 223         ENTRY;
 224         spin_lock(&ns->ns_unused_lock);
 225         ldlm_lock_add_to_lru_nolock(lock);
 226         spin_unlock(&ns->ns_unused_lock);
 227         EXIT;
 228 }
 229
 230 void ldlm_lock_touch_in_lru(struct ldlm_lock *lock)
 231 {
 232         struct ldlm_namespace *ns = lock->l_resource->lr_namespace;
 233         ENTRY;
 234         spin_lock(&ns->ns_unused_lock);
 235         if (!list_empty(&lock->l_lru)) {
 236                 ldlm_lock_remove_from_lru_nolock(lock);
 237                 ldlm_lock_add_to_lru_nolock(lock);
 238         }
 239         spin_unlock(&ns->ns_unused_lock);
 240         EXIT;
 241 }
 242
 243 /* This used to have a 'strict' flag, which recovery would use to mark an
 244  * in-use lock as needing-to-die.  Lest I am ever tempted to put it back, I
 245  * shall explain why it's gone: with the new hash table scheme, once you call
 246  * ldlm_lock_destroy, you can never drop your final references on this lock.
 247  * Because it's not in the hash table anymore.  -phil */
 248 int ldlm_lock_destroy_internal(struct ldlm_lock *lock)
 249 {
 250         ENTRY;
 251
 252         if (lock->l_readers || lock->l_writers) {
 253                 LDLM_ERROR(lock, "lock still has references");
 254                 ldlm_lock_dump(D_ERROR, lock, 0);
 255                 LBUG();
 256         }
 257
 258         if (!list_empty(&lock->l_res_link)) {
 259                 LDLM_ERROR(lock, "lock still on resource");
 260                 ldlm_lock_dump(D_ERROR, lock, 0);
 261                 LBUG();
 262         }
 263
 264         if (lock->l_destroyed) {
 265                 LASSERT(list_empty(&lock->l_lru));
 266                 EXIT;
 267                 return 0;
 268         }
 269         lock->l_destroyed = 1;
 270
 271         if (lock->l_export && lock->l_export->exp_lock_hash &&
 272             !hlist_unhashed(&lock->l_exp_hash))
 273                 lustre_hash_del(lock->l_export->exp_lock_hash,
 274                                 &lock->l_remote_handle, &lock->l_exp_hash);
 275
 276         ldlm_lock_remove_from_lru(lock);
 277         class_handle_unhash(&lock->l_handle);
 278
 279 #if 0
 280         /* Wake anyone waiting for this lock */
 281         /* FIXME: I should probably add yet another flag, instead of using
 282          * l_export to only call this on clients */
 283         if (lock->l_export)
 284                 class_export_put(lock->l_export);
 285         lock->l_export = NULL;
 286         if (lock->l_export && lock->l_completion_ast)
 287                 lock->l_completion_ast(lock, 0);
 288 #endif
 289         EXIT;
 290         return 1;
 291 }
 292
 293 void ldlm_lock_destroy(struct ldlm_lock *lock)
 294 {
 295         int first;
 296         ENTRY;
 297         lock_res_and_lock(lock);
 298         first = ldlm_lock_destroy_internal(lock);
 299         unlock_res_and_lock(lock);
 300
 301         /* drop reference from hashtable only for first destroy */
 302         if (first) {
 303                 lu_ref_del(&lock->l_reference, "hash", lock);
 304                 LDLM_LOCK_RELEASE(lock);
 305         }
 306         EXIT;
 307 }
 308
 309 void ldlm_lock_destroy_nolock(struct ldlm_lock *lock)
 310 {
 311         int first;
 312         ENTRY;
 313         first = ldlm_lock_destroy_internal(lock);
 314         /* drop reference from hashtable only for first destroy */
 315         if (first) {
 316                 lu_ref_del(&lock->l_reference, "hash", lock);
 317                 LDLM_LOCK_RELEASE(lock);
 318         }
 319         EXIT;
 320 }
 321
 322 /* this is called by portals_handle2object with the handle lock taken */
 323 static void lock_handle_addref(void *lock)
 324 {
 325         LDLM_LOCK_GET((struct ldlm_lock *)lock);
 326 }
 327
 328 /*
 329  * usage: pass in a resource on which you have done ldlm_resource_get
 330  *        pass in a parent lock on which you have done a ldlm_lock_get
 331  *        after return, ldlm_*_put the resource and parent
 332  * returns: lock with refcount 2 - one for current caller and one for remote
 333  */
 334 static struct ldlm_lock *ldlm_lock_new(struct ldlm_resource *resource)
 335 {
 336         struct ldlm_lock *lock;
 337         ENTRY;
 338
 339         if (resource == NULL)
 340                 LBUG();
 341
 342         OBD_SLAB_ALLOC_PTR_GFP(lock, ldlm_lock_slab, CFS_ALLOC_IO);
 343         if (lock == NULL)
 344                 RETURN(NULL);
 345
 346         spin_lock_init(&lock->l_lock);
 347         lock->l_resource = ldlm_resource_getref(resource);
 348         lu_ref_add(&resource->lr_reference, "lock", lock);
 349
 350         atomic_set(&lock->l_refc, 2);
 351         CFS_INIT_LIST_HEAD(&lock->l_res_link);
 352         CFS_INIT_LIST_HEAD(&lock->l_lru);
 353         CFS_INIT_LIST_HEAD(&lock->l_pending_chain);
 354         CFS_INIT_LIST_HEAD(&lock->l_bl_ast);
 355         CFS_INIT_LIST_HEAD(&lock->l_cp_ast);
 356         CFS_INIT_LIST_HEAD(&lock->l_rk_ast);
 357         cfs_waitq_init(&lock->l_waitq);
 358         lock->l_blocking_lock = NULL;
 359         CFS_INIT_LIST_HEAD(&lock->l_sl_mode);
 360         CFS_INIT_LIST_HEAD(&lock->l_sl_policy);
 361         CFS_INIT_HLIST_NODE(&lock->l_exp_hash);
 362
 363         atomic_inc(&resource->lr_namespace->ns_locks);
 364         CFS_INIT_LIST_HEAD(&lock->l_handle.h_link);
 365         class_handle_hash(&lock->l_handle, lock_handle_addref);
 366
 367         CFS_INIT_LIST_HEAD(&lock->l_extents_list);
 368         spin_lock_init(&lock->l_extents_list_lock);
 369         CFS_INIT_LIST_HEAD(&lock->l_cache_locks_list);
 370         lu_ref_init(&lock->l_reference);
 371         lu_ref_add(&lock->l_reference, "hash", lock);
 372         lock->l_callback_timeout = 0;
 373
 374         RETURN(lock);
 375 }
 376
 377 int ldlm_lock_change_resource(struct ldlm_namespace *ns, struct ldlm_lock *lock,
 378                               const struct ldlm_res_id *new_resid)
 379 {
 380         struct ldlm_resource *oldres = lock->l_resource;
 381         struct ldlm_resource *newres;
 382         int type;
 383         ENTRY;
 384
 385         LASSERT(ns_is_client(ns));
 386
 387         lock_res_and_lock(lock);
 388         if (memcmp(new_resid, &lock->l_resource->lr_name,
 389                    sizeof(lock->l_resource->lr_name)) == 0) {
 390                 /* Nothing to do */
 391                 unlock_res_and_lock(lock);
 392                 RETURN(0);
 393         }
 394
 395         LASSERT(new_resid->name[0] != 0);
 396
 397         /* This function assumes that the lock isn't on any lists */
 398         LASSERT(list_empty(&lock->l_res_link));
 399
 400         type = oldres->lr_type;
 401         unlock_res_and_lock(lock);
 402
 403         newres = ldlm_resource_get(ns, NULL, new_resid, type, 1);
 404         lu_ref_add(&newres->lr_reference, "lock", lock);
 405         if (newres == NULL)
 406                 RETURN(-ENOMEM);
 407         /*
 408          * To flip the lock from the old to the new resource, lock, oldres and
 409          * newres have to be locked. Resource spin-locks are nested within
 410          * lock->l_lock, and are taken in the memory address order to avoid
 411          * dead-locks.
 412          */
 413         spin_lock(&lock->l_lock);
 414         oldres = lock->l_resource;
 415         if (oldres < newres) {
 416                 lock_res(oldres);
 417                 lock_res_nested(newres, LRT_NEW);
 418         } else {
 419                 lock_res(newres);
 420                 lock_res_nested(oldres, LRT_NEW);
 421         }
 422         LASSERT(memcmp(new_resid, &oldres->lr_name,
 423                        sizeof oldres->lr_name) != 0);
 424         lock->l_resource = newres;
 425         unlock_res(oldres);
 426         unlock_res_and_lock(lock);
 427
 428         /* ...and the flowers are still standing! */
 429         lu_ref_del(&oldres->lr_reference, "lock", lock);
 430         ldlm_resource_putref(oldres);
 431
 432         RETURN(0);
 433 }
 434
 435 /*
 436  *  HANDLES
 437  */
 438
 439 void ldlm_lock2handle(const struct ldlm_lock *lock, struct lustre_handle *lockh)
 440 {
 441         lockh->cookie = lock->l_handle.h_cookie;
 442 }
 443
 444 /* if flags: atomically get the lock and set the flags.
 445  *           Return NULL if flag already set
 446  */
 447
 448 struct ldlm_lock *__ldlm_handle2lock(const struct lustre_handle *handle,
 449                                      int flags)
 450 {
 451         struct ldlm_namespace *ns;
 452         struct ldlm_lock *lock, *retval = NULL;
 453         ENTRY;
 454
 455         LASSERT(handle);
 456
 457         lock = class_handle2object(handle->cookie);
 458         if (lock == NULL)
 459                 RETURN(NULL);
 460
 461         LASSERT(lock->l_resource != NULL);
 462         ns = lock->l_resource->lr_namespace;
 463         LASSERT(ns != NULL);
 464
 465         lu_ref_add_atomic(&lock->l_reference, "handle", cfs_current());
 466         lock_res_and_lock(lock);
 467
 468         /* It's unlikely but possible that someone marked the lock as
 469          * destroyed after we did handle2object on it */
 470         if (lock->l_destroyed) {
 471                 unlock_res_and_lock(lock);
 472                 CDEBUG(D_INFO, "lock already destroyed: lock %p\n", lock);
 473                 LDLM_LOCK_PUT(lock);
 474                 GOTO(out, retval);
 475         }
 476
 477         if (flags && (lock->l_flags & flags)) {
 478                 unlock_res_and_lock(lock);
 479                 LDLM_LOCK_PUT(lock);
 480                 GOTO(out, retval);
 481         }
 482
 483         if (flags)
 484                 lock->l_flags |= flags;
 485
 486         unlock_res_and_lock(lock);
 487         retval = lock;
 488         EXIT;
 489  out:
 490         return retval;
 491 }
 492
 493 void ldlm_lock2desc(struct ldlm_lock *lock, struct ldlm_lock_desc *desc)
 494 {
 495         struct obd_export *exp = lock->l_export?:lock->l_conn_export;
 496         /* INODEBITS_INTEROP: If the other side does not support
 497          * inodebits, reply with a plain lock descriptor.
 498          */
 499         if ((lock->l_resource->lr_type == LDLM_IBITS) &&
 500             (exp && !(exp->exp_connect_flags & OBD_CONNECT_IBITS))) {
 501                 struct ldlm_resource res = *lock->l_resource;
 502
 503                 /* Make sure all the right bits are set in this lock we
 504                    are going to pass to client */
 505                 LASSERTF(lock->l_policy_data.l_inodebits.bits ==
 506                          (MDS_INODELOCK_LOOKUP|MDS_INODELOCK_UPDATE),
 507                          "Inappropriate inode lock bits during "
 508                          "conversion " LPU64 "\n",
 509                          lock->l_policy_data.l_inodebits.bits);
 510                 res.lr_type = LDLM_PLAIN;
 511                 ldlm_res2desc(&res, &desc->l_resource);
 512                 /* Convert "new" lock mode to something old client can
 513                    understand */
 514                 if ((lock->l_req_mode == LCK_CR) ||
 515                     (lock->l_req_mode == LCK_CW))
 516                         desc->l_req_mode = LCK_PR;
 517                 else
 518                         desc->l_req_mode = lock->l_req_mode;
 519                 if ((lock->l_granted_mode == LCK_CR) ||
 520                     (lock->l_granted_mode == LCK_CW)) {
 521                         desc->l_granted_mode = LCK_PR;
 522                 } else {
 523                         /* We never grant PW/EX locks to clients */
 524                         LASSERT((lock->l_granted_mode != LCK_PW) &&
 525                                 (lock->l_granted_mode != LCK_EX));
 526                         desc->l_granted_mode = lock->l_granted_mode;
 527                 }
 528
 529                 /* We do not copy policy here, because there is no
 530                    policy for plain locks */
 531         } else {
 532                 ldlm_res2desc(lock->l_resource, &desc->l_resource);
 533                 desc->l_req_mode = lock->l_req_mode;
 534                 desc->l_granted_mode = lock->l_granted_mode;
 535                 desc->l_policy_data = lock->l_policy_data;
 536         }
 537 }
 538
 539 void ldlm_add_bl_work_item(struct ldlm_lock *lock, struct ldlm_lock *new,
 540                            struct list_head *work_list)
 541 {
 542         if ((lock->l_flags & LDLM_FL_AST_SENT) == 0) {
 543                 LDLM_DEBUG(lock, "lock incompatible; sending blocking AST.");
 544                 lock->l_flags |= LDLM_FL_AST_SENT;
 545                 /* If the enqueuing client said so, tell the AST recipient to
 546                  * discard dirty data, rather than writing back. */
 547                 if (new->l_flags & LDLM_AST_DISCARD_DATA)
 548                         lock->l_flags |= LDLM_FL_DISCARD_DATA;
 549                 LASSERT(list_empty(&lock->l_bl_ast));
 550                 list_add(&lock->l_bl_ast, work_list);
 551                 LDLM_LOCK_GET(lock);
 552                 LASSERT(lock->l_blocking_lock == NULL);
 553                 lock->l_blocking_lock = LDLM_LOCK_GET(new);
 554         }
 555 }
 556
 557 void ldlm_add_cp_work_item(struct ldlm_lock *lock, struct list_head *work_list)
 558 {
 559         if ((lock->l_flags & LDLM_FL_CP_REQD) == 0) {
 560                 lock->l_flags |= LDLM_FL_CP_REQD;
 561                 LDLM_DEBUG(lock, "lock granted; sending completion AST.");
 562                 LASSERT(list_empty(&lock->l_cp_ast));
 563                 list_add(&lock->l_cp_ast, work_list);
 564                 LDLM_LOCK_GET(lock);
 565         }
 566 }
 567
 568 /* must be called with lr_lock held */
 569 void ldlm_add_ast_work_item(struct ldlm_lock *lock, struct ldlm_lock *new,
 570                                 struct list_head *work_list)
 571 {
 572         ENTRY;
 573         check_res_locked(lock->l_resource);
 574         if (new)
 575                 ldlm_add_bl_work_item(lock, new, work_list);
 576         else
 577                 ldlm_add_cp_work_item(lock, work_list);
 578         EXIT;
 579 }
 580
 581 void ldlm_lock_addref(struct lustre_handle *lockh, __u32 mode)
 582 {
 583         struct ldlm_lock *lock;
 584
 585         lock = ldlm_handle2lock(lockh);
 586         LASSERT(lock != NULL);
 587         ldlm_lock_addref_internal(lock, mode);
 588         LDLM_LOCK_PUT(lock);
 589 }
 590
 591 void ldlm_lock_addref_internal_nolock(struct ldlm_lock *lock, __u32 mode)
 592 {
 593         ldlm_lock_remove_from_lru(lock);
 594         if (mode & (LCK_NL | LCK_CR | LCK_PR)) {
 595                 lock->l_readers++;
 596                 lu_ref_add_atomic(&lock->l_reference, "reader", lock);
 597         }
 598         if (mode & (LCK_EX | LCK_CW | LCK_PW | LCK_GROUP | LCK_COS)) {
 599                 lock->l_writers++;
 600                 lu_ref_add_atomic(&lock->l_reference, "writer", lock);
 601         }
 602         LDLM_LOCK_GET(lock);
 603         lu_ref_add_atomic(&lock->l_reference, "user", lock);
 604         LDLM_DEBUG(lock, "ldlm_lock_addref(%s)", ldlm_lockname[mode]);
 605 }
 606
 607 /**
 608  * Attempts to addref a lock, and fails if lock is already LDLM_FL_CBPENDING
 609  * or destroyed.
 610  *
 611  * \retval 0 success, lock was addref-ed
 612  *
 613  * \retval -EAGAIN lock is being canceled.
 614  */
 615 int ldlm_lock_addref_try(struct lustre_handle *lockh, __u32 mode)
 616 {
 617         struct ldlm_lock *lock;
 618         int               result;
 619
 620         result = -EAGAIN;
 621         lock = ldlm_handle2lock(lockh);
 622         if (lock != NULL) {
 623                 lock_res_and_lock(lock);
 624                 if (lock->l_readers != 0 || lock->l_writers != 0 ||
 625                     !(lock->l_flags & LDLM_FL_CBPENDING)) {
 626                         ldlm_lock_addref_internal_nolock(lock, mode);
 627                         result = 0;
 628                 }
 629                 unlock_res_and_lock(lock);
 630                 LDLM_LOCK_PUT(lock);
 631         }
 632         return result;
 633 }
 634
 635 /* only called for local locks */
 636 void ldlm_lock_addref_internal(struct ldlm_lock *lock, __u32 mode)
 637 {
 638         lock_res_and_lock(lock);
 639         ldlm_lock_addref_internal_nolock(lock, mode);
 640         unlock_res_and_lock(lock);
 641 }
 642
 643 /* only called in ldlm_flock_destroy and for local locks.
 644  *  * for LDLM_FLOCK type locks, l_blocking_ast is null, and
 645  *   * ldlm_lock_remove_from_lru() does nothing, it is safe
 646  *    * for ldlm_flock_destroy usage by dropping some code */
 647 void ldlm_lock_decref_internal_nolock(struct ldlm_lock *lock, __u32 mode)
 648 {
 649         LDLM_DEBUG(lock, "ldlm_lock_decref(%s)", ldlm_lockname[mode]);
 650         if (mode & (LCK_NL | LCK_CR | LCK_PR)) {
 651                 LASSERT(lock->l_readers > 0);
 652                 lu_ref_del(&lock->l_reference, "reader", lock);
 653                 lock->l_readers--;
 654         }
 655         if (mode & (LCK_EX | LCK_CW | LCK_PW | LCK_GROUP | LCK_COS)) {
 656                 LASSERT(lock->l_writers > 0);
 657                 lu_ref_del(&lock->l_reference, "writer", lock);
 658                 lock->l_writers--;
 659         }
 660
 661         lu_ref_del(&lock->l_reference, "user", lock);
 662         LDLM_LOCK_RELEASE(lock);    /* matches the LDLM_LOCK_GET() in addref */
 663 }
 664
 665 void ldlm_lock_decref_internal(struct ldlm_lock *lock, __u32 mode)
 666 {
 667         struct ldlm_namespace *ns;
 668         ENTRY;
 669
 670         lock_res_and_lock(lock);
 671
 672         ns = lock->l_resource->lr_namespace;
 673
 674         ldlm_lock_decref_internal_nolock(lock, mode);
 675
 676         if (lock->l_flags & LDLM_FL_LOCAL &&
 677             !lock->l_readers && !lock->l_writers) {
 678                 /* If this is a local lock on a server namespace and this was
 679                  * the last reference, cancel the lock. */
 680                 CDEBUG(D_INFO, "forcing cancel of local lock\n");
 681                 lock->l_flags |= LDLM_FL_CBPENDING;
 682         }
 683
 684         if (!lock->l_readers && !lock->l_writers &&
 685             (lock->l_flags & LDLM_FL_CBPENDING)) {
 686                 /* If we received a blocked AST and this was the last reference,
 687                  * run the callback. */
 688                 if (ns_is_server(ns) && lock->l_export)
 689                         CERROR("FL_CBPENDING set on non-local lock--just a "
 690                                "warning\n");
 691
 692                 LDLM_DEBUG(lock, "final decref done on cbpending lock");
 693
 694                 LDLM_LOCK_GET(lock); /* dropped by bl thread */
 695                 ldlm_lock_remove_from_lru(lock);
 696                 unlock_res_and_lock(lock);
 697
 698                 if (lock->l_flags & LDLM_FL_FAIL_LOC)
 699                         OBD_RACE(OBD_FAIL_LDLM_CP_BL_RACE);
 700
 701                 if ((lock->l_flags & LDLM_FL_ATOMIC_CB) ||
 702                     ldlm_bl_to_thread_lock(ns, NULL, lock) != 0)
 703                         ldlm_handle_bl_callback(ns, NULL, lock);
 704         } else if (ns_is_client(ns) &&
 705                    !lock->l_readers && !lock->l_writers &&
 706                    !(lock->l_flags & LDLM_FL_BL_AST)) {
 707                 /* If this is a client-side namespace and this was the last
 708                  * reference, put it on the LRU. */
 709                 ldlm_lock_add_to_lru(lock);
 710                 unlock_res_and_lock(lock);
 711
 712                 if (lock->l_flags & LDLM_FL_FAIL_LOC)
 713                         OBD_RACE(OBD_FAIL_LDLM_CP_BL_RACE);
 714
 715                 /* Call ldlm_cancel_lru() only if EARLY_CANCEL and LRU RESIZE
 716                  * are not supported by the server, otherwise, it is done on
 717                  * enqueue. */
 718                 if (!exp_connect_cancelset(lock->l_conn_export) &&
 719                     !ns_connect_lru_resize(ns))
 720                         ldlm_cancel_lru(ns, 0, LDLM_ASYNC, 0);
 721         } else {
 722                 unlock_res_and_lock(lock);
 723         }
 724
 725         EXIT;
 726 }
 727
 728 void ldlm_lock_decref(struct lustre_handle *lockh, __u32 mode)
 729 {
 730         struct ldlm_lock *lock = __ldlm_handle2lock(lockh, 0);
 731         LASSERTF(lock != NULL, "Non-existing lock: "LPX64"\n", lockh->cookie);
 732         ldlm_lock_decref_internal(lock, mode);
 733         LDLM_LOCK_PUT(lock);
 734 }
 735
 736 /* This will drop a lock reference and mark it for destruction, but will not
 737  * necessarily cancel the lock before returning. */
 738 void ldlm_lock_decref_and_cancel(struct lustre_handle *lockh, __u32 mode)
 739 {
 740         struct ldlm_lock *lock = __ldlm_handle2lock(lockh, 0);
 741         ENTRY;
 742
 743         LASSERT(lock != NULL);
 744
 745         LDLM_DEBUG(lock, "ldlm_lock_decref(%s)", ldlm_lockname[mode]);
 746         lock_res_and_lock(lock);
 747         lock->l_flags |= LDLM_FL_CBPENDING;
 748         unlock_res_and_lock(lock);
 749         ldlm_lock_decref_internal(lock, mode);
 750         LDLM_LOCK_PUT(lock);
 751 }
 752
 753 struct sl_insert_point {
 754         struct list_head *res_link;
 755         struct list_head *mode_link;
 756         struct list_head *policy_link;
 757 };
 758
 759 /*
 760  * search_granted_lock
 761  *
 762  * Description:
 763  *      Finds a position to insert the new lock.
 764  * Parameters:
 765  *      queue [input]:  the granted list where search acts on;
 766  *      req [input]:    the lock whose position to be located;
 767  *      prev [output]:  positions within 3 lists to insert @req to
 768  * Return Value:
 769  *      filled @prev
 770  * NOTE: called by
 771  *  - ldlm_grant_lock_with_skiplist
 772  */
 773 static void search_granted_lock(struct list_head *queue,
 774                                 struct ldlm_lock *req,
 775                                 struct sl_insert_point *prev)
 776 {
 777         struct list_head *tmp;
 778         struct ldlm_lock *lock, *mode_end, *policy_end;
 779         ENTRY;
 780
 781         list_for_each(tmp, queue) {
 782                 lock = list_entry(tmp, struct ldlm_lock, l_res_link);
 783
 784                 mode_end = list_entry(lock->l_sl_mode.prev, struct ldlm_lock,
 785                                       l_sl_mode);
 786
 787                 if (lock->l_req_mode != req->l_req_mode) {
 788                         /* jump to last lock of mode group */
 789                         tmp = &mode_end->l_res_link;
 790                         continue;
 791                 }
 792
 793                 /* suitable mode group is found */
 794                 if (lock->l_resource->lr_type == LDLM_PLAIN) {
 795                         /* insert point is last lock of the mode group */
 796                         prev->res_link = &mode_end->l_res_link;
 797                         prev->mode_link = &mode_end->l_sl_mode;
 798                         prev->policy_link = &req->l_sl_policy;
 799                         EXIT;
 800                         return;
 801                 } else if (lock->l_resource->lr_type == LDLM_IBITS) {
 802                         for (;;) {
 803                                 policy_end = list_entry(lock->l_sl_policy.prev,
 804                                                         struct ldlm_lock,
 805                                                         l_sl_policy);
 806
 807                                 if (lock->l_policy_data.l_inodebits.bits ==
 808                                     req->l_policy_data.l_inodebits.bits) {
 809                                         /* insert point is last lock of
 810                                          * the policy group */
 811                                         prev->res_link =
 812                                                 &policy_end->l_res_link;
 813                                         prev->mode_link =
 814                                                 &policy_end->l_sl_mode;
 815                                         prev->policy_link =
 816                                                 &policy_end->l_sl_policy;
 817                                         EXIT;
 818                                         return;
 819                                 }
 820
 821                                 if (policy_end == mode_end)
 822                                         /* done with mode group */
 823                                         break;
 824
 825                                 /* go to next policy group within mode group */
 826                                 tmp = policy_end->l_res_link.next;
 827                                 lock = list_entry(tmp, struct ldlm_lock,
 828                                                   l_res_link);
 829                         }  /* loop over policy groups within the mode group */
 830
 831                         /* insert point is last lock of the mode group,
 832                          * new policy group is started */
 833                         prev->res_link = &mode_end->l_res_link;
 834                         prev->mode_link = &mode_end->l_sl_mode;
 835                         prev->policy_link = &req->l_sl_policy;
 836                         EXIT;
 837                         return;
 838                 } else {
 839                         LDLM_ERROR(lock,"is not LDLM_PLAIN or LDLM_IBITS lock");
 840                         LBUG();
 841                 }
 842         }
 843
 844         /* insert point is last lock on the queue,
 845          * new mode group and new policy group are started */
 846         prev->res_link = queue->prev;
 847         prev->mode_link = &req->l_sl_mode;
 848         prev->policy_link = &req->l_sl_policy;
 849         EXIT;
 850         return;
 851 }
 852
 853 static void ldlm_granted_list_add_lock(struct ldlm_lock *lock,
 854                                        struct sl_insert_point *prev)
 855 {
 856         struct ldlm_resource *res = lock->l_resource;
 857         ENTRY;
 858
 859         check_res_locked(res);
 860
 861         ldlm_resource_dump(D_INFO, res);
 862         CDEBUG(D_OTHER, "About to add this lock:\n");
 863         ldlm_lock_dump(D_OTHER, lock, 0);
 864
 865         if (lock->l_destroyed) {
 866                 CDEBUG(D_OTHER, "Lock destroyed, not adding to resource\n");
 867                 return;
 868         }
 869
 870         LASSERT(list_empty(&lock->l_res_link));
 871         LASSERT(list_empty(&lock->l_sl_mode));
 872         LASSERT(list_empty(&lock->l_sl_policy));
 873
 874         list_add(&lock->l_res_link, prev->res_link);
 875         list_add(&lock->l_sl_mode, prev->mode_link);
 876         list_add(&lock->l_sl_policy, prev->policy_link);
 877
 878         EXIT;
 879 }
 880
 881 static void ldlm_grant_lock_with_skiplist(struct ldlm_lock *lock)
 882 {
 883         struct sl_insert_point prev;
 884         ENTRY;
 885
 886         LASSERT(lock->l_req_mode == lock->l_granted_mode);
 887
 888         search_granted_lock(&lock->l_resource->lr_granted, lock, &prev);
 889         ldlm_granted_list_add_lock(lock, &prev);
 890         EXIT;
 891 }
 892
 893 /* NOTE: called by
 894  *  - ldlm_lock_enqueue
 895  *  - ldlm_reprocess_queue
 896  *  - ldlm_lock_convert
 897  *
 898  * must be called with lr_lock held
 899  */
 900 void ldlm_grant_lock(struct ldlm_lock *lock, struct list_head *work_list)
 901 {
 902         struct ldlm_resource *res = lock->l_resource;
 903         ENTRY;
 904
 905         check_res_locked(res);
 906
 907         lock->l_granted_mode = lock->l_req_mode;
 908         if (res->lr_type == LDLM_PLAIN || res->lr_type == LDLM_IBITS)
 909                 ldlm_grant_lock_with_skiplist(lock);
 910         else if (res->lr_type == LDLM_EXTENT)
 911                 ldlm_extent_add_lock(res, lock);
 912         else
 913                 ldlm_resource_add_lock(res, &res->lr_granted, lock);
 914
 915         if (lock->l_granted_mode < res->lr_most_restr)
 916                 res->lr_most_restr = lock->l_granted_mode;
 917
 918         if (work_list && lock->l_completion_ast != NULL)
 919                 ldlm_add_ast_work_item(lock, NULL, work_list);
 920
 921         ldlm_pool_add(&res->lr_namespace->ns_pool, lock);
 922         EXIT;
 923 }
 924
 925 /* returns a referenced lock or NULL.  See the flag descriptions below, in the
 926  * comment above ldlm_lock_match */
 927 static struct ldlm_lock *search_queue(struct list_head *queue,
 928                                       ldlm_mode_t *mode,
 929                                       ldlm_policy_data_t *policy,
 930                                       struct ldlm_lock *old_lock,
 931                                       int flags, int unref)
 932 {
 933         struct ldlm_lock *lock;
 934         struct list_head *tmp;
 935
 936         list_for_each(tmp, queue) {
 937                 ldlm_mode_t match;
 938
 939                 lock = list_entry(tmp, struct ldlm_lock, l_res_link);
 940
 941                 if (lock == old_lock)
 942                         break;
 943
 944                 /* llite sometimes wants to match locks that will be
 945                  * canceled when their users drop, but we allow it to match
 946                  * if it passes in CBPENDING and the lock still has users.
 947                  * this is generally only going to be used by children
 948                  * whose parents already hold a lock so forward progress
 949                  * can still happen. */
 950                 if (lock->l_flags & LDLM_FL_CBPENDING &&
 951                     !(flags & LDLM_FL_CBPENDING))
 952                         continue;
 953                 if (!unref && lock->l_flags & LDLM_FL_CBPENDING &&
 954                     lock->l_readers == 0 && lock->l_writers == 0)
 955                         continue;
 956
 957                 if (!(lock->l_req_mode & *mode))
 958                         continue;
 959                 match = lock->l_req_mode;
 960
 961                 if (lock->l_resource->lr_type == LDLM_EXTENT &&
 962                     (lock->l_policy_data.l_extent.start >
 963                      policy->l_extent.start ||
 964                      lock->l_policy_data.l_extent.end < policy->l_extent.end))
 965                         continue;
 966
 967                 if (unlikely(match == LCK_GROUP) &&
 968                     lock->l_resource->lr_type == LDLM_EXTENT &&
 969                     lock->l_policy_data.l_extent.gid != policy->l_extent.gid)
 970                         continue;
 971
 972                 /* We match if we have existing lock with same or wider set
 973                    of bits. */
 974                 if (lock->l_resource->lr_type == LDLM_IBITS &&
 975                      ((lock->l_policy_data.l_inodebits.bits &
 976                       policy->l_inodebits.bits) !=
 977                       policy->l_inodebits.bits))
 978                         continue;
 979
 980                 if (!unref &&
 981                     (lock->l_destroyed || (lock->l_flags & LDLM_FL_FAILED)))
 982                         continue;
 983
 984                 if ((flags & LDLM_FL_LOCAL_ONLY) &&
 985                     !(lock->l_flags & LDLM_FL_LOCAL))
 986                         continue;
 987
 988                 if (flags & LDLM_FL_TEST_LOCK) {
 989                         LDLM_LOCK_GET(lock);
 990                         ldlm_lock_touch_in_lru(lock);
 991                 } else {
 992                         ldlm_lock_addref_internal_nolock(lock, match);
 993                 }
 994                 *mode = match;
 995                 return lock;
 996         }
 997
 998         return NULL;
 999 }
1000
1001 void ldlm_lock_allow_match_locked(struct ldlm_lock *lock)
1002 {
1003         lock->l_flags |= LDLM_FL_LVB_READY;
1004         cfs_waitq_signal(&lock->l_waitq);
1005 }
1006
1007 void ldlm_lock_allow_match(struct ldlm_lock *lock)
1008 {
1009         lock_res_and_lock(lock);
1010         ldlm_lock_allow_match_locked(lock);
1011         unlock_res_and_lock(lock);
1012 }
1013
1014 /* Can be called in two ways:
1015  *
1016  * If 'ns' is NULL, then lockh describes an existing lock that we want to look
1017  * for a duplicate of.
1018  *
1019  * Otherwise, all of the fields must be filled in, to match against.
1020  *
1021  * If 'flags' contains LDLM_FL_LOCAL_ONLY, then only match local locks on the
1022  *     server (ie, connh is NULL)
1023  * If 'flags' contains LDLM_FL_BLOCK_GRANTED, then only locks on the granted
1024  *     list will be considered
1025  * If 'flags' contains LDLM_FL_CBPENDING, then locks that have been marked
1026  *     to be canceled can still be matched as long as they still have reader
1027  *     or writer refernces
1028  * If 'flags' contains LDLM_FL_TEST_LOCK, then don't actually reference a lock,
1029  *     just tell us if we would have matched.
1030  *
1031  * Returns 1 if it finds an already-existing lock that is compatible; in this
1032  * case, lockh is filled in with a addref()ed lock
1033  *
1034  * we also check security context, if that failed we simply return 0 (to keep
1035  * caller code unchanged), the context failure will be discovered by caller
1036  * sometime later.
1037  */
1038 ldlm_mode_t ldlm_lock_match(struct ldlm_namespace *ns, int flags,
1039                             const struct ldlm_res_id *res_id, ldlm_type_t type,
1040                             ldlm_policy_data_t *policy, ldlm_mode_t mode,
1041                             struct lustre_handle *lockh, int unref)
1042 {
1043         struct ldlm_resource *res;
1044         struct ldlm_lock *lock, *old_lock = NULL;
1045         int rc = 0;
1046         ENTRY;
1047
1048         if (ns == NULL) {
1049                 old_lock = ldlm_handle2lock(lockh);
1050                 LASSERT(old_lock);
1051
1052                 ns = old_lock->l_resource->lr_namespace;
1053                 res_id = &old_lock->l_resource->lr_name;
1054                 type = old_lock->l_resource->lr_type;
1055                 mode = old_lock->l_req_mode;
1056         }
1057
1058         res = ldlm_resource_get(ns, NULL, res_id, type, 0);
1059         if (res == NULL) {
1060                 LASSERT(old_lock == NULL);
1061                 RETURN(0);
1062         }
1063
1064         LDLM_RESOURCE_ADDREF(res);
1065         lock_res(res);
1066
1067         lock = search_queue(&res->lr_granted, &mode, policy, old_lock,
1068                             flags, unref);
1069         if (lock != NULL)
1070                 GOTO(out, rc = 1);
1071         if (flags & LDLM_FL_BLOCK_GRANTED)
1072                 GOTO(out, rc = 0);
1073         lock = search_queue(&res->lr_converting, &mode, policy, old_lock,
1074                             flags, unref);
1075         if (lock != NULL)
1076                 GOTO(out, rc = 1);
1077         lock = search_queue(&res->lr_waiting, &mode, policy, old_lock,
1078                             flags, unref);
1079         if (lock != NULL)
1080                 GOTO(out, rc = 1);
1081
1082         EXIT;
1083  out:
1084         unlock_res(res);
1085         LDLM_RESOURCE_DELREF(res);
1086         ldlm_resource_putref(res);
1087
1088         if (lock) {
1089                 ldlm_lock2handle(lock, lockh);
1090                 if ((flags & LDLM_FL_LVB_READY) &&
1091                     (!(lock->l_flags & LDLM_FL_LVB_READY))) {
1092                         struct l_wait_info lwi;
1093                         if (lock->l_completion_ast) {
1094                                 int err = lock->l_completion_ast(lock,
1095                                                           LDLM_FL_WAIT_NOREPROC,
1096                                                                  NULL);
1097                                 if (err) {
1098                                         if (flags & LDLM_FL_TEST_LOCK)
1099                                                 LDLM_LOCK_RELEASE(lock);
1100                                         else
1101                                                 ldlm_lock_decref_internal(lock,
1102                                                                           mode);
1103                                         rc = 0;
1104                                         goto out2;
1105                                 }
1106                         }
1107
1108                         lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(obd_timeout),
1109                                                NULL, LWI_ON_SIGNAL_NOOP, NULL);
1110
1111                         /* XXX FIXME see comment on CAN_MATCH in lustre_dlm.h */
1112                         l_wait_event(lock->l_waitq,
1113                                      (lock->l_flags & LDLM_FL_LVB_READY), &lwi);
1114                 }
1115         }
1116  out2:
1117         if (rc) {
1118                 LDLM_DEBUG(lock, "matched ("LPU64" "LPU64")",
1119                            (type == LDLM_PLAIN || type == LDLM_IBITS) ?
1120                                 res_id->name[2] : policy->l_extent.start,
1121                            (type == LDLM_PLAIN || type == LDLM_IBITS) ?
1122                                 res_id->name[3] : policy->l_extent.end);
1123
1124                 /* check user's security context */
1125                 if (lock->l_conn_export &&
1126                     sptlrpc_import_check_ctx(
1127                                 class_exp2cliimp(lock->l_conn_export))) {
1128                         if (!(flags & LDLM_FL_TEST_LOCK))
1129                                 ldlm_lock_decref_internal(lock, mode);
1130                         rc = 0;
1131                 }
1132
1133                 if (flags & LDLM_FL_TEST_LOCK)
1134                         LDLM_LOCK_RELEASE(lock);
1135
1136         } else if (!(flags & LDLM_FL_TEST_LOCK)) {/*less verbose for test-only*/
1137                 LDLM_DEBUG_NOLOCK("not matched ns %p type %u mode %u res "
1138                                   LPU64"/"LPU64" ("LPU64" "LPU64")", ns,
1139                                   type, mode, res_id->name[0], res_id->name[1],
1140                                   (type == LDLM_PLAIN || type == LDLM_IBITS) ?
1141                                         res_id->name[2] :policy->l_extent.start,
1142                                 (type == LDLM_PLAIN || type == LDLM_IBITS) ?
1143                                         res_id->name[3] : policy->l_extent.end);
1144         }
1145         if (old_lock)
1146                 LDLM_LOCK_PUT(old_lock);
1147
1148         return rc ? mode : 0;
1149 }
1150
1151 /* Returns a referenced lock */
1152 struct ldlm_lock *ldlm_lock_create(struct ldlm_namespace *ns,
1153                                    const struct ldlm_res_id *res_id,
1154                                    ldlm_type_t type,
1155                                    ldlm_mode_t mode,
1156                                    const struct ldlm_callback_suite *cbs,
1157                                    void *data, __u32 lvb_len)
1158 {
1159         struct ldlm_lock *lock;
1160         struct ldlm_resource *res;
1161         ENTRY;
1162
1163         res = ldlm_resource_get(ns, NULL, res_id, type, 1);
1164         if (res == NULL)
1165                 RETURN(NULL);
1166
1167         lock = ldlm_lock_new(res);
1168         ldlm_resource_putref(res);
1169
1170         if (lock == NULL)
1171                 RETURN(NULL);
1172
1173         lock->l_req_mode = mode;
1174         lock->l_ast_data = data;
1175         lock->l_pid = cfs_curproc_pid();
1176         if (cbs) {
1177                 lock->l_blocking_ast = cbs->lcs_blocking;
1178                 lock->l_completion_ast = cbs->lcs_completion;
1179                 lock->l_glimpse_ast = cbs->lcs_glimpse;
1180                 lock->l_weigh_ast = cbs->lcs_weigh;
1181         }
1182
1183         lock->l_tree_node = NULL;
1184         /* if this is the extent lock, allocate the interval tree node */
1185         if (type == LDLM_EXTENT) {
1186                 if (ldlm_interval_alloc(lock) == NULL)
1187                         GOTO(out, 0);
1188         }
1189
1190         if (lvb_len) {
1191                 lock->l_lvb_len = lvb_len;
1192                 OBD_ALLOC(lock->l_lvb_data, lvb_len);
1193                 if (lock->l_lvb_data == NULL)
1194                         GOTO(out, 0);
1195         }
1196
1197         RETURN(lock);
1198
1199 out:
1200         if (lock->l_lvb_data)
1201                 OBD_FREE(lock->l_lvb_data, lvb_len);
1202         ldlm_interval_free(ldlm_interval_detach(lock));
1203         OBD_SLAB_FREE(lock, ldlm_lock_slab, sizeof(*lock));
1204         return NULL;
1205 }
1206
1207 ldlm_error_t ldlm_lock_enqueue(struct ldlm_namespace *ns,
1208                                struct ldlm_lock **lockp,
1209                                void *cookie, int *flags)
1210 {
1211         struct ldlm_lock *lock = *lockp;
1212         struct ldlm_resource *res = lock->l_resource;
1213         int local = ns_is_client(res->lr_namespace);
1214         ldlm_processing_policy policy;
1215         ldlm_error_t rc = ELDLM_OK;
1216         struct ldlm_interval *node = NULL;
1217         ENTRY;
1218
1219         lock->l_last_activity = cfs_time_current_sec();
1220         /* policies are not executed on the client or during replay */
1221         if ((*flags & (LDLM_FL_HAS_INTENT|LDLM_FL_REPLAY)) == LDLM_FL_HAS_INTENT
1222             && !local && ns->ns_policy) {
1223                 rc = ns->ns_policy(ns, lockp, cookie, lock->l_req_mode, *flags,
1224                                    NULL);
1225                 if (rc == ELDLM_LOCK_REPLACED) {
1226                         /* The lock that was returned has already been granted,
1227                          * and placed into lockp.  If it's not the same as the
1228                          * one we passed in, then destroy the old one and our
1229                          * work here is done. */
1230                         if (lock != *lockp) {
1231                                 ldlm_lock_destroy(lock);
1232                                 LDLM_LOCK_RELEASE(lock);
1233                         }
1234                         *flags |= LDLM_FL_LOCK_CHANGED;
1235                         RETURN(0);
1236                 } else if (rc != ELDLM_OK ||
1237                            (rc == ELDLM_OK && (*flags & LDLM_FL_INTENT_ONLY))) {
1238                         ldlm_lock_destroy(lock);
1239                         RETURN(rc);
1240                 }
1241         }
1242
1243         /* For a replaying lock, it might be already in granted list. So
1244          * unlinking the lock will cause the interval node to be freed, we
1245          * have to allocate the interval node early otherwise we can't regrant
1246          * this lock in the future. - jay */
1247         if (!local && (*flags & LDLM_FL_REPLAY) && res->lr_type == LDLM_EXTENT)
1248                 OBD_SLAB_ALLOC_PTR_GFP(node, ldlm_interval_slab, CFS_ALLOC_IO);
1249
1250         lock_res_and_lock(lock);
1251         if (local && lock->l_req_mode == lock->l_granted_mode) {
1252                 /* The server returned a blocked lock, but it was granted
1253                  * before we got a chance to actually enqueue it.  We don't
1254                  * need to do anything else. */
1255                 *flags &= ~(LDLM_FL_BLOCK_GRANTED |
1256                             LDLM_FL_BLOCK_CONV | LDLM_FL_BLOCK_WAIT);
1257                 GOTO(out, ELDLM_OK);
1258         }
1259
1260         ldlm_resource_unlink_lock(lock);
1261         if (res->lr_type == LDLM_EXTENT && lock->l_tree_node == NULL) {
1262                 if (node == NULL) {
1263                         ldlm_lock_destroy_nolock(lock);
1264                         GOTO(out, rc = -ENOMEM);
1265                 }
1266
1267                 CFS_INIT_LIST_HEAD(&node->li_group);
1268                 ldlm_interval_attach(node, lock);
1269                 node = NULL;
1270         }
1271
1272         /* Some flags from the enqueue want to make it into the AST, via the
1273          * lock's l_flags. */
1274         lock->l_flags |= *flags & LDLM_AST_DISCARD_DATA;
1275
1276         /* This distinction between local lock trees is very important; a client
1277          * namespace only has information about locks taken by that client, and
1278          * thus doesn't have enough information to decide for itself if it can
1279          * be granted (below).  In this case, we do exactly what the server
1280          * tells us to do, as dictated by the 'flags'.
1281          *
1282          * We do exactly the same thing during recovery, when the server is
1283          * more or less trusting the clients not to lie.
1284          *
1285          * FIXME (bug 268): Detect obvious lies by checking compatibility in
1286          * granted/converting queues. */
1287         if (local) {
1288                 if (*flags & LDLM_FL_BLOCK_CONV)
1289                         ldlm_resource_add_lock(res, &res->lr_converting, lock);
1290                 else if (*flags & (LDLM_FL_BLOCK_WAIT | LDLM_FL_BLOCK_GRANTED))
1291                         ldlm_resource_add_lock(res, &res->lr_waiting, lock);
1292                 else
1293                         ldlm_grant_lock(lock, NULL);
1294                 GOTO(out, ELDLM_OK);
1295         } else if (*flags & LDLM_FL_REPLAY) {
1296                 if (*flags & LDLM_FL_BLOCK_CONV) {
1297                         ldlm_resource_add_lock(res, &res->lr_converting, lock);
1298                         GOTO(out, ELDLM_OK);
1299                 } else if (*flags & LDLM_FL_BLOCK_WAIT) {
1300                         ldlm_resource_add_lock(res, &res->lr_waiting, lock);
1301                         GOTO(out, ELDLM_OK);
1302                 } else if (*flags & LDLM_FL_BLOCK_GRANTED) {
1303                         ldlm_grant_lock(lock, NULL);
1304                         GOTO(out, ELDLM_OK);
1305                 }
1306                 /* If no flags, fall through to normal enqueue path. */
1307         }
1308
1309         policy = ldlm_processing_policy_table[res->lr_type];
1310         policy(lock, flags, 1, &rc, NULL);
1311         GOTO(out, rc);
1312 out:
1313         unlock_res_and_lock(lock);
1314         if (node)
1315                 OBD_SLAB_FREE(node, ldlm_interval_slab, sizeof(*node));
1316         return rc;
1317 }
1318
1319 /* Must be called with namespace taken: queue is waiting or converting. */
1320 int ldlm_reprocess_queue(struct ldlm_resource *res, struct list_head *queue,
1321                          struct list_head *work_list)
1322 {
1323         struct list_head *tmp, *pos;
1324         ldlm_processing_policy policy;
1325         int flags;
1326         int rc = LDLM_ITER_CONTINUE;
1327         ldlm_error_t err;
1328         ENTRY;
1329
1330         check_res_locked(res);
1331
1332         policy = ldlm_processing_policy_table[res->lr_type];
1333         LASSERT(policy);
1334
1335         list_for_each_safe(tmp, pos, queue) {
1336                 struct ldlm_lock *pending;
1337                 pending = list_entry(tmp, struct ldlm_lock, l_res_link);
1338
1339                 CDEBUG(D_INFO, "Reprocessing lock %p\n", pending);
1340
1341                 flags = 0;
1342                 rc = policy(pending, &flags, 0, &err, work_list);
1343                 if (rc != LDLM_ITER_CONTINUE)
1344                         break;
1345         }
1346
1347         RETURN(rc);
1348 }
1349
1350 /* Helper function for ldlm_run_ast_work().
1351  *
1352  * Send an existing rpc set specified by @arg->set and then
1353  * destroy it. Create new one if @do_create flag is set. */
1354 static void
1355 ldlm_send_and_maybe_create_set(struct ldlm_cb_set_arg *arg, int do_create)
1356 {
1357         ENTRY;
1358
1359         ptlrpc_set_wait(arg->set);
1360         if (arg->type == LDLM_BL_CALLBACK)
1361                 OBD_FAIL_TIMEOUT(OBD_FAIL_LDLM_GLIMPSE, 2);
1362         ptlrpc_set_destroy(arg->set);
1363
1364         if (do_create)
1365                 arg->set = ptlrpc_prep_set();
1366
1367         EXIT;
1368 }
1369
1370 static int
1371 ldlm_work_bl_ast_lock(struct list_head *tmp, struct ldlm_cb_set_arg *arg)
1372 {
1373         struct ldlm_lock_desc d;
1374         struct ldlm_lock *lock = list_entry(tmp, struct ldlm_lock, l_bl_ast);
1375         ENTRY;
1376
1377         /* nobody should touch l_bl_ast */
1378         lock_res_and_lock(lock);
1379         list_del_init(&lock->l_bl_ast);
1380
1381         LASSERT(lock->l_flags & LDLM_FL_AST_SENT);
1382         LASSERT(lock->l_bl_ast_run == 0);
1383         LASSERT(lock->l_blocking_lock);
1384         lock->l_bl_ast_run++;
1385         unlock_res_and_lock(lock);
1386
1387         ldlm_lock2desc(lock->l_blocking_lock, &d);
1388
1389         lock->l_blocking_ast(lock, &d, (void *)arg,
1390                              LDLM_CB_BLOCKING);
1391         LDLM_LOCK_RELEASE(lock->l_blocking_lock);
1392         lock->l_blocking_lock = NULL;
1393         LDLM_LOCK_RELEASE(lock);
1394
1395         RETURN(1);
1396 }
1397
1398 static int
1399 ldlm_work_cp_ast_lock(struct list_head *tmp, struct ldlm_cb_set_arg *arg)
1400 {
1401         struct ldlm_lock *lock = list_entry(tmp, struct ldlm_lock, l_cp_ast);
1402         ldlm_completion_callback completion_callback;
1403         int rc = 0;
1404         ENTRY;
1405
1406         /* It's possible to receive a completion AST before we've set
1407          * the l_completion_ast pointer: either because the AST arrived
1408          * before the reply, or simply because there's a small race
1409          * window between receiving the reply and finishing the local
1410          * enqueue. (bug 842)
1411          *
1412          * This can't happen with the blocking_ast, however, because we
1413          * will never call the local blocking_ast until we drop our
1414          * reader/writer reference, which we won't do until we get the
1415          * reply and finish enqueueing. */
1416
1417         /* nobody should touch l_cp_ast */
1418         lock_res_and_lock(lock);
1419         list_del_init(&lock->l_cp_ast);
1420         LASSERT(lock->l_flags & LDLM_FL_CP_REQD);
1421         /* save l_completion_ast since it can be changed by
1422          * mds_intent_policy(), see bug 14225 */
1423         completion_callback = lock->l_completion_ast;
1424         lock->l_flags &= ~LDLM_FL_CP_REQD;
1425         unlock_res_and_lock(lock);
1426
1427         if (completion_callback != NULL) {
1428                 completion_callback(lock, 0, (void *)arg);
1429                 rc = 1;
1430         }
1431         LDLM_LOCK_RELEASE(lock);
1432
1433         RETURN(rc);
1434 }
1435
1436 static int
1437 ldlm_work_revoke_ast_lock(struct list_head *tmp, struct ldlm_cb_set_arg *arg)
1438 {
1439         struct ldlm_lock_desc desc;
1440         struct ldlm_lock *lock = list_entry(tmp, struct ldlm_lock, l_rk_ast);
1441         ENTRY;
1442
1443         list_del_init(&lock->l_rk_ast);
1444
1445         /* the desc just pretend to exclusive */
1446         ldlm_lock2desc(lock, &desc);
1447         desc.l_req_mode = LCK_EX;
1448         desc.l_granted_mode = 0;
1449
1450         lock->l_blocking_ast(lock, &desc, (void*)arg, LDLM_CB_BLOCKING);
1451         LDLM_LOCK_RELEASE(lock);
1452
1453         RETURN(1);
1454 }
1455
1456 int ldlm_run_ast_work(struct list_head *rpc_list, ldlm_desc_ast_t ast_type)
1457 {
1458         struct ldlm_cb_set_arg arg;
1459         struct list_head *tmp, *pos;
1460         int (*work_ast_lock)(struct list_head *tmp,struct ldlm_cb_set_arg *arg);
1461         int ast_count;
1462         ENTRY;
1463
1464         arg.set = ptlrpc_prep_set();
1465         atomic_set(&arg.restart, 0);
1466         switch (ast_type) {
1467         case LDLM_WORK_BL_AST:
1468                 arg.type = LDLM_BL_CALLBACK;
1469                 work_ast_lock = ldlm_work_bl_ast_lock;
1470                 break;
1471         case LDLM_WORK_CP_AST:
1472                 arg.type = LDLM_CP_CALLBACK;
1473                 work_ast_lock = ldlm_work_cp_ast_lock;
1474                 break;
1475         case LDLM_WORK_REVOKE_AST:
1476                 arg.type = LDLM_BL_CALLBACK;
1477                 work_ast_lock = ldlm_work_revoke_ast_lock;
1478                 break;
1479         default:
1480                 LBUG();
1481         }
1482
1483         ast_count = 0;
1484         list_for_each_safe(tmp, pos, rpc_list) {
1485                 ast_count += work_ast_lock(tmp, &arg);
1486
1487                 /* Send the request set if it exceeds the PARALLEL_AST_LIMIT,
1488                  * and create a new set for requests that remained in
1489                  * @rpc_list */
1490                 if (unlikely(ast_count == PARALLEL_AST_LIMIT)) {
1491                         ldlm_send_and_maybe_create_set(&arg, 1);
1492                         ast_count = 0;
1493                 }
1494         }
1495
1496         if (ast_count > 0)
1497                 ldlm_send_and_maybe_create_set(&arg, 0);
1498         else
1499                 /* In case when number of ASTs is multiply of
1500                  * PARALLEL_AST_LIMIT or @rpc_list was initially empty,
1501                  * @arg.set must be destroyed here, otherwise we get
1502                  * write memory leaking. */
1503                 ptlrpc_set_destroy(arg.set);
1504
1505         RETURN(atomic_read(&arg.restart) ? -ERESTART : 0);
1506 }
1507
1508 static int reprocess_one_queue(struct ldlm_resource *res, void *closure)
1509 {
1510         ldlm_reprocess_all(res);
1511         return LDLM_ITER_CONTINUE;
1512 }
1513
1514 void ldlm_reprocess_all_ns(struct ldlm_namespace *ns)
1515 {
1516         struct list_head *tmp;
1517         int i, rc;
1518
1519         if (ns == NULL)
1520                 return;
1521
1522         ENTRY;
1523         spin_lock(&ns->ns_hash_lock);
1524         for (i = 0; i < RES_HASH_SIZE; i++) {
1525                 tmp = ns->ns_hash[i].next;
1526                 while (tmp != &(ns->ns_hash[i])) {
1527                         struct ldlm_resource *res =
1528                                 list_entry(tmp, struct ldlm_resource, lr_hash);
1529
1530                         ldlm_resource_getref(res);
1531                         spin_unlock(&ns->ns_hash_lock);
1532                         LDLM_RESOURCE_ADDREF(res);
1533
1534                         rc = reprocess_one_queue(res, NULL);
1535
1536                         LDLM_RESOURCE_DELREF(res);
1537                         spin_lock(&ns->ns_hash_lock);
1538                         tmp = tmp->next;
1539                         ldlm_resource_putref_locked(res);
1540
1541                         if (rc == LDLM_ITER_STOP)
1542                                 GOTO(out, rc);
1543                 }
1544         }
1545  out:
1546         spin_unlock(&ns->ns_hash_lock);
1547         EXIT;
1548 }
1549
1550 void ldlm_reprocess_all(struct ldlm_resource *res)
1551 {
1552         CFS_LIST_HEAD(rpc_list);
1553         int rc;
1554         ENTRY;
1555
1556         /* Local lock trees don't get reprocessed. */
1557         if (ns_is_client(res->lr_namespace)) {
1558                 EXIT;
1559                 return;
1560         }
1561
1562  restart:
1563         lock_res(res);
1564         rc = ldlm_reprocess_queue(res, &res->lr_converting, &rpc_list);
1565         if (rc == LDLM_ITER_CONTINUE)
1566                 ldlm_reprocess_queue(res, &res->lr_waiting, &rpc_list);
1567         unlock_res(res);
1568
1569         rc = ldlm_run_ast_work(&rpc_list, LDLM_WORK_CP_AST);
1570         if (rc == -ERESTART) {
1571                 LASSERT(list_empty(&rpc_list));
1572                 goto restart;
1573         }
1574         EXIT;
1575 }
1576
1577 void ldlm_cancel_callback(struct ldlm_lock *lock)
1578 {
1579         check_res_locked(lock->l_resource);
1580         if (!(lock->l_flags & LDLM_FL_CANCEL)) {
1581                 lock->l_flags |= LDLM_FL_CANCEL;
1582                 if (lock->l_blocking_ast) {
1583                         // l_check_no_ns_lock(ns);
1584                         unlock_res_and_lock(lock);
1585                         lock->l_blocking_ast(lock, NULL, lock->l_ast_data,
1586                                              LDLM_CB_CANCELING);
1587                         lock_res_and_lock(lock);
1588                 } else {
1589                         LDLM_DEBUG(lock, "no blocking ast");
1590                 }
1591         }
1592         lock->l_flags |= LDLM_FL_BL_DONE;
1593 }
1594
1595 void ldlm_unlink_lock_skiplist(struct ldlm_lock *req)
1596 {
1597         if (req->l_resource->lr_type != LDLM_PLAIN &&
1598             req->l_resource->lr_type != LDLM_IBITS)
1599                 return;
1600
1601         list_del_init(&req->l_sl_policy);
1602         list_del_init(&req->l_sl_mode);
1603 }
1604
1605 void ldlm_lock_cancel(struct ldlm_lock *lock)
1606 {
1607         struct ldlm_resource *res;
1608         struct ldlm_namespace *ns;
1609         ENTRY;
1610
1611         lock_res_and_lock(lock);
1612
1613         res = lock->l_resource;
1614         ns = res->lr_namespace;
1615
1616         /* Please do not, no matter how tempting, remove this LBUG without
1617          * talking to me first. -phik */
1618         if (lock->l_readers || lock->l_writers) {
1619                 LDLM_ERROR(lock, "lock still has references");
1620                 LBUG();
1621         }
1622
1623         ldlm_del_waiting_lock(lock);
1624
1625         /* Releases cancel callback. */
1626         ldlm_cancel_callback(lock);
1627
1628         /* Yes, second time, just in case it was added again while we were
1629            running with no res lock in ldlm_cancel_callback */
1630         ldlm_del_waiting_lock(lock);
1631         ldlm_resource_unlink_lock(lock);
1632         ldlm_lock_destroy_nolock(lock);
1633
1634         if (lock->l_granted_mode == lock->l_req_mode)
1635                 ldlm_pool_del(&ns->ns_pool, lock);
1636
1637         /* Make sure we will not be called again for same lock what is possible
1638          * if not to zero out lock->l_granted_mode */
1639         lock->l_granted_mode = LCK_MINMODE;
1640         unlock_res_and_lock(lock);
1641
1642         EXIT;
1643 }
1644
1645 int ldlm_lock_set_data(struct lustre_handle *lockh, void *data)
1646 {
1647         struct ldlm_lock *lock = ldlm_handle2lock(lockh);
1648         ENTRY;
1649
1650         if (lock == NULL)
1651                 RETURN(-EINVAL);
1652
1653         lock->l_ast_data = data;
1654         LDLM_LOCK_PUT(lock);
1655         RETURN(0);
1656 }
1657
1658 void ldlm_cancel_locks_for_export_cb(void *obj, void *data)
1659 {
1660         struct obd_export    *exp = data;
1661         struct ldlm_lock     *lock = obj;
1662         struct ldlm_resource *res;
1663
1664         res = ldlm_resource_getref(lock->l_resource);
1665         LDLM_LOCK_GET(lock);
1666
1667         LDLM_DEBUG(lock, "export %p", exp);
1668         ldlm_res_lvbo_update(res, NULL, 0, 1);
1669         ldlm_lock_cancel(lock);
1670         ldlm_reprocess_all(res);
1671         ldlm_resource_putref(res);
1672         LDLM_LOCK_RELEASE(lock);
1673 }
1674
1675 void ldlm_cancel_locks_for_export(struct obd_export *exp)
1676 {
1677         lustre_hash_for_each_empty(exp->exp_lock_hash,
1678                                    ldlm_cancel_locks_for_export_cb, exp);
1679 }
1680
1681 /**
1682  * Downgrade an exclusive lock.
1683  *
1684  * A fast variant of ldlm_lock_convert for convertion of exclusive
1685  * locks. The convertion is always successful.
1686  *
1687  * \param lock A lock to convert
1688  * \param new_mode new lock mode
1689  */
1690 void ldlm_lock_downgrade(struct ldlm_lock *lock, int new_mode)
1691 {
1692         struct ldlm_namespace *ns;
1693         ENTRY;
1694
1695         LASSERT(lock->l_granted_mode & (LCK_PW | LCK_EX));
1696         LASSERT(new_mode == LCK_COS);
1697
1698         lock_res_and_lock(lock);
1699         ldlm_resource_unlink_lock(lock);
1700         /*
1701          * Remove the lock from pool as it will be added again in
1702          * ldlm_grant_lock() called below.
1703          */
1704         ns = lock->l_resource->lr_namespace;
1705         ldlm_pool_del(&ns->ns_pool, lock);
1706
1707         lock->l_req_mode = new_mode;
1708         ldlm_grant_lock(lock, NULL);
1709         unlock_res_and_lock(lock);
1710         ldlm_reprocess_all(lock->l_resource);
1711
1712         EXIT;
1713 }
1714
1715 struct ldlm_resource *ldlm_lock_convert(struct ldlm_lock *lock, int new_mode,
1716                                         __u32 *flags)
1717 {
1718         CFS_LIST_HEAD(rpc_list);
1719         struct ldlm_resource *res;
1720         struct ldlm_namespace *ns;
1721         int granted = 0;
1722         int old_mode, rc;
1723         struct sl_insert_point prev;
1724         ldlm_error_t err;
1725         struct ldlm_interval *node;
1726         ENTRY;
1727
1728         if (new_mode == lock->l_granted_mode) { // No changes? Just return.
1729                 *flags |= LDLM_FL_BLOCK_GRANTED;
1730                 RETURN(lock->l_resource);
1731         }
1732
1733         /* I can't check the type of lock here because the bitlock of lock
1734          * is not held here, so do the allocation blindly. -jay */
1735         OBD_SLAB_ALLOC_PTR_GFP(node, ldlm_interval_slab, CFS_ALLOC_IO);
1736         if (node == NULL)  /* Actually, this causes EDEADLOCK to be returned */
1737                 RETURN(NULL);
1738
1739         LASSERTF((new_mode == LCK_PW && lock->l_granted_mode == LCK_PR),
1740                  "new_mode %u, granted %u\n", new_mode, lock->l_granted_mode);
1741
1742         lock_res_and_lock(lock);
1743
1744         res = lock->l_resource;
1745         ns = res->lr_namespace;
1746
1747         old_mode = lock->l_req_mode;
1748         lock->l_req_mode = new_mode;
1749         if (res->lr_type == LDLM_PLAIN || res->lr_type == LDLM_IBITS) {
1750                 /* remember the lock position where the lock might be
1751                  * added back to the granted list later and also
1752                  * remember the join mode for skiplist fixing. */
1753                 prev.res_link = lock->l_res_link.prev;
1754                 prev.mode_link = lock->l_sl_mode.prev;
1755                 prev.policy_link = lock->l_sl_policy.prev;
1756                 ldlm_resource_unlink_lock(lock);
1757         } else {
1758                 ldlm_resource_unlink_lock(lock);
1759                 if (res->lr_type == LDLM_EXTENT) {
1760                         /* FIXME: ugly code, I have to attach the lock to a
1761                          * interval node again since perhaps it will be granted
1762                          * soon */
1763                         CFS_INIT_LIST_HEAD(&node->li_group);
1764                         ldlm_interval_attach(node, lock);
1765                         node = NULL;
1766                 }
1767         }
1768
1769         /*
1770          * Remove old lock from the pool before adding the lock with new
1771          * mode below in ->policy()
1772          */
1773         ldlm_pool_del(&ns->ns_pool, lock);
1774
1775         /* If this is a local resource, put it on the appropriate list. */
1776         if (ns_is_client(res->lr_namespace)) {
1777                 if (*flags & (LDLM_FL_BLOCK_CONV | LDLM_FL_BLOCK_GRANTED)) {
1778                         ldlm_resource_add_lock(res, &res->lr_converting, lock);
1779                 } else {
1780                         /* This should never happen, because of the way the
1781                          * server handles conversions. */
1782                         LDLM_ERROR(lock, "Erroneous flags %d on local lock\n",
1783                                    *flags);
1784                         LBUG();
1785
1786                         ldlm_grant_lock(lock, &rpc_list);
1787                         granted = 1;
1788                         /* FIXME: completion handling not with ns_lock held ! */
1789                         if (lock->l_completion_ast)
1790                                 lock->l_completion_ast(lock, 0, NULL);
1791                 }
1792         } else {
1793                 int pflags = 0;
1794                 ldlm_processing_policy policy;
1795                 policy = ldlm_processing_policy_table[res->lr_type];
1796                 rc = policy(lock, &pflags, 0, &err, &rpc_list);
1797                 if (rc == LDLM_ITER_STOP) {
1798                         lock->l_req_mode = old_mode;
1799                         if (res->lr_type == LDLM_EXTENT)
1800                                 ldlm_extent_add_lock(res, lock);
1801                         else
1802                                 ldlm_granted_list_add_lock(lock, &prev);
1803
1804                         res = NULL;
1805                 } else {
1806                         *flags |= LDLM_FL_BLOCK_GRANTED;
1807                         granted = 1;
1808                 }
1809         }
1810         unlock_res_and_lock(lock);
1811
1812         if (granted)
1813                 ldlm_run_ast_work(&rpc_list, LDLM_WORK_CP_AST);
1814         if (node)
1815                 OBD_SLAB_FREE(node, ldlm_interval_slab, sizeof(*node));
1816         RETURN(res);
1817 }
1818
1819 void ldlm_lock_dump(int level, struct ldlm_lock *lock, int pos)
1820 {
1821         struct obd_device *obd = NULL;
1822
1823         if (!((libcfs_debug | D_ERROR) & level))
1824                 return;
1825
1826         if (!lock) {
1827                 CDEBUG(level, "  NULL LDLM lock\n");
1828                 return;
1829         }
1830
1831         CDEBUG(level," -- Lock dump: %p/"LPX64" (rc: %d) (pos: %d) (pid: %d)\n",
1832                lock, lock->l_handle.h_cookie, atomic_read(&lock->l_refc),
1833                pos, lock->l_pid);
1834         if (lock->l_conn_export != NULL)
1835                 obd = lock->l_conn_export->exp_obd;
1836         if (lock->l_export && lock->l_export->exp_connection) {
1837                 CDEBUG(level, "  Node: NID %s (rhandle: "LPX64")\n",
1838                      libcfs_nid2str(lock->l_export->exp_connection->c_peer.nid),
1839                      lock->l_remote_handle.cookie);
1840         } else if (obd == NULL) {
1841                 CDEBUG(level, "  Node: local\n");
1842         } else {
1843                 struct obd_import *imp = obd->u.cli.cl_import;
1844                 CDEBUG(level, "  Node: NID %s (rhandle: "LPX64")\n",
1845                        libcfs_nid2str(imp->imp_connection->c_peer.nid),
1846                        lock->l_remote_handle.cookie);
1847         }
1848         CDEBUG(level, "  Resource: %p ("LPU64"/"LPU64"/"LPU64")\n",
1849                   lock->l_resource,
1850                   lock->l_resource->lr_name.name[0],
1851                   lock->l_resource->lr_name.name[1],
1852                   lock->l_resource->lr_name.name[2]);
1853         CDEBUG(level, "  Req mode: %s, grant mode: %s, rc: %u, read: %d, "
1854                "write: %d flags: "LPX64"\n", ldlm_lockname[lock->l_req_mode],
1855                ldlm_lockname[lock->l_granted_mode],
1856                atomic_read(&lock->l_refc), lock->l_readers, lock->l_writers,
1857                lock->l_flags);
1858         if (lock->l_resource->lr_type == LDLM_EXTENT)
1859                 CDEBUG(level, "  Extent: "LPU64" -> "LPU64
1860                        " (req "LPU64"-"LPU64")\n",
1861                        lock->l_policy_data.l_extent.start,
1862                        lock->l_policy_data.l_extent.end,
1863                        lock->l_req_extent.start, lock->l_req_extent.end);
1864         else if (lock->l_resource->lr_type == LDLM_FLOCK)
1865                 CDEBUG(level, "  Pid: %d Extent: "LPU64" -> "LPU64"\n",
1866                        lock->l_policy_data.l_flock.pid,
1867                        lock->l_policy_data.l_flock.start,
1868                        lock->l_policy_data.l_flock.end);
1869        else if (lock->l_resource->lr_type == LDLM_IBITS)
1870                 CDEBUG(level, "  Bits: "LPX64"\n",
1871                        lock->l_policy_data.l_inodebits.bits);
1872 }
1873
1874 void ldlm_lock_dump_handle(int level, struct lustre_handle *lockh)
1875 {
1876         struct ldlm_lock *lock;
1877
1878         if (!((libcfs_debug | D_ERROR) & level))
1879                 return;
1880
1881         lock = ldlm_handle2lock(lockh);
1882         if (lock == NULL)
1883                 return;
1884
1885         ldlm_lock_dump(D_OTHER, lock, 0);
1886
1887         LDLM_LOCK_PUT(lock);
1888 }
1889
1890 void _ldlm_lock_debug(struct ldlm_lock *lock, __u32 level,
1891                       struct libcfs_debug_msg_data *data, const char *fmt,
1892                       ...)
1893 {
1894         va_list args;
1895         cfs_debug_limit_state_t *cdls = data->msg_cdls;
1896
1897         va_start(args, fmt);
1898
1899         if (lock->l_resource == NULL) {
1900                 libcfs_debug_vmsg2(cdls, data->msg_subsys, level,data->msg_file,
1901                                    data->msg_fn, data->msg_line, fmt, args,
1902                        " ns: \?\? lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
1903                                    "res: \?\? rrc=\?\? type: \?\?\? flags: "LPX64" remote: "
1904                        LPX64" expref: %d pid: %u timeout: %lu\n", lock,
1905                        lock->l_handle.h_cookie, atomic_read(&lock->l_refc),
1906                        lock->l_readers, lock->l_writers,
1907                        ldlm_lockname[lock->l_granted_mode],
1908                        ldlm_lockname[lock->l_req_mode],
1909                        lock->l_flags, lock->l_remote_handle.cookie,
1910                        lock->l_export ?
1911                        atomic_read(&lock->l_export->exp_refcount) : -99,
1912                        lock->l_pid, lock->l_callback_timeout);
1913                 va_end(args);
1914                 return;
1915         }
1916
1917         switch (lock->l_resource->lr_type) {
1918         case LDLM_EXTENT:
1919                 libcfs_debug_vmsg2(cdls, data->msg_subsys, level,data->msg_file,
1920                                    data->msg_fn, data->msg_line, fmt, args,
1921                        " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
1922                        "res: "LPU64"/"LPU64" rrc: %d type: %s ["LPU64"->"LPU64
1923                                    "] (req "LPU64"->"LPU64") flags: "LPX64" remote: "LPX64
1924                        " expref: %d pid: %u timeout %lu\n",
1925                        lock->l_resource->lr_namespace->ns_name, lock,
1926                        lock->l_handle.h_cookie, atomic_read(&lock->l_refc),
1927                        lock->l_readers, lock->l_writers,
1928                        ldlm_lockname[lock->l_granted_mode],
1929                        ldlm_lockname[lock->l_req_mode],
1930                        lock->l_resource->lr_name.name[0],
1931                        lock->l_resource->lr_name.name[1],
1932                        atomic_read(&lock->l_resource->lr_refcount),
1933                        ldlm_typename[lock->l_resource->lr_type],
1934                        lock->l_policy_data.l_extent.start,
1935                        lock->l_policy_data.l_extent.end,
1936                        lock->l_req_extent.start, lock->l_req_extent.end,
1937                        lock->l_flags, lock->l_remote_handle.cookie,
1938                        lock->l_export ?
1939                        atomic_read(&lock->l_export->exp_refcount) : -99,
1940                        lock->l_pid, lock->l_callback_timeout);
1941                 break;
1942
1943         case LDLM_FLOCK:
1944                 libcfs_debug_vmsg2(cdls, data->msg_subsys, level,data->msg_file,
1945                                    data->msg_fn, data->msg_line, fmt, args,
1946                        " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
1947                        "res: "LPU64"/"LPU64" rrc: %d type: %s pid: %d "
1948                                    "["LPU64"->"LPU64"] flags: "LPX64" remote: "LPX64
1949                        " expref: %d pid: %u timeout: %lu\n",
1950                        lock->l_resource->lr_namespace->ns_name, lock,
1951                        lock->l_handle.h_cookie, atomic_read(&lock->l_refc),
1952                        lock->l_readers, lock->l_writers,
1953                        ldlm_lockname[lock->l_granted_mode],
1954                        ldlm_lockname[lock->l_req_mode],
1955                        lock->l_resource->lr_name.name[0],
1956                        lock->l_resource->lr_name.name[1],
1957                        atomic_read(&lock->l_resource->lr_refcount),
1958                        ldlm_typename[lock->l_resource->lr_type],
1959                        lock->l_policy_data.l_flock.pid,
1960                        lock->l_policy_data.l_flock.start,
1961                        lock->l_policy_data.l_flock.end,
1962                        lock->l_flags, lock->l_remote_handle.cookie,
1963                        lock->l_export ?
1964                        atomic_read(&lock->l_export->exp_refcount) : -99,
1965                        lock->l_pid, lock->l_callback_timeout);
1966                 break;
1967
1968         case LDLM_IBITS:
1969                 libcfs_debug_vmsg2(cdls, data->msg_subsys, level,data->msg_file,
1970                                    data->msg_fn, data->msg_line, fmt, args,
1971                        " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
1972                        "res: "LPU64"/"LPU64" bits "LPX64" rrc: %d type: %s "
1973                                    "flags: "LPX64" remote: "LPX64" expref: %d "
1974                        "pid: %u timeout: %lu\n",
1975                        lock->l_resource->lr_namespace->ns_name,
1976                        lock, lock->l_handle.h_cookie,
1977                        atomic_read (&lock->l_refc),
1978                        lock->l_readers, lock->l_writers,
1979                        ldlm_lockname[lock->l_granted_mode],
1980                        ldlm_lockname[lock->l_req_mode],
1981                        lock->l_resource->lr_name.name[0],
1982                        lock->l_resource->lr_name.name[1],
1983                        lock->l_policy_data.l_inodebits.bits,
1984                        atomic_read(&lock->l_resource->lr_refcount),
1985                        ldlm_typename[lock->l_resource->lr_type],
1986                        lock->l_flags, lock->l_remote_handle.cookie,
1987                        lock->l_export ?
1988                        atomic_read(&lock->l_export->exp_refcount) : -99,
1989                        lock->l_pid, lock->l_callback_timeout);
1990                 break;
1991
1992         default:
1993                 libcfs_debug_vmsg2(cdls, data->msg_subsys, level,data->msg_file,
1994                                    data->msg_fn, data->msg_line, fmt, args,
1995                        " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
1996                                    "res: "LPU64"/"LPU64" rrc: %d type: %s flags: "LPX64" "
1997                        "remote: "LPX64" expref: %d pid: %u timeout %lu\n",
1998                        lock->l_resource->lr_namespace->ns_name,
1999                        lock, lock->l_handle.h_cookie,
2000                        atomic_read (&lock->l_refc),
2001                        lock->l_readers, lock->l_writers,
2002                        ldlm_lockname[lock->l_granted_mode],
2003                        ldlm_lockname[lock->l_req_mode],
2004                        lock->l_resource->lr_name.name[0],
2005                        lock->l_resource->lr_name.name[1],
2006                        atomic_read(&lock->l_resource->lr_refcount),
2007                        ldlm_typename[lock->l_resource->lr_type],
2008                        lock->l_flags, lock->l_remote_handle.cookie,
2009                        lock->l_export ?
2010                        atomic_read(&lock->l_export->exp_refcount) : -99,
2011                        lock->l_pid, lock->l_callback_timeout);
2012                 break;
2013         }
2014         va_end(args);
2015 }
2016 EXPORT_SYMBOL(_ldlm_lock_debug);