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 (c) 2002, 2010, Oracle and/or its affiliates. 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         cfs_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(cfs_atomic_read(&lock->l_refc) > 0);
 151         if (cfs_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(cfs_list_empty(&lock->l_res_link));
 160                 LASSERT(cfs_list_empty(&lock->l_pending_chain));
 161
 162                 cfs_atomic_dec(&ldlm_res_to_ns(res)->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_lock_put(lock->l_export, lock);
 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 (!cfs_list_empty(&lock->l_lru)) {
 187                 struct ldlm_namespace *ns = ldlm_lock_to_ns(lock);
 188
 189                 LASSERT(lock->l_resource->lr_type != LDLM_FLOCK);
 190                 cfs_list_del_init(&lock->l_lru);
 191                 if (lock->l_flags & LDLM_FL_SKIPPED)
 192                         lock->l_flags &= ~LDLM_FL_SKIPPED;
 193                 LASSERT(ns->ns_nr_unused > 0);
 194                 ns->ns_nr_unused--;
 195                 rc = 1;
 196         }
 197         return rc;
 198 }
 199
 200 int ldlm_lock_remove_from_lru(struct ldlm_lock *lock)
 201 {
 202         struct ldlm_namespace *ns = ldlm_lock_to_ns(lock);
 203         int rc;
 204
 205         ENTRY;
 206         if (lock->l_ns_srv) {
 207                 LASSERT(cfs_list_empty(&lock->l_lru));
 208                 RETURN(0);
 209         }
 210
 211         cfs_spin_lock(&ns->ns_unused_lock);
 212         rc = ldlm_lock_remove_from_lru_nolock(lock);
 213         cfs_spin_unlock(&ns->ns_unused_lock);
 214         EXIT;
 215         return rc;
 216 }
 217
 218 void ldlm_lock_add_to_lru_nolock(struct ldlm_lock *lock)
 219 {
 220         struct ldlm_namespace *ns = ldlm_lock_to_ns(lock);
 221
 222         lock->l_last_used = cfs_time_current();
 223         LASSERT(cfs_list_empty(&lock->l_lru));
 224         LASSERT(lock->l_resource->lr_type != LDLM_FLOCK);
 225         cfs_list_add_tail(&lock->l_lru, &ns->ns_unused_list);
 226         LASSERT(ns->ns_nr_unused >= 0);
 227         ns->ns_nr_unused++;
 228 }
 229
 230 void ldlm_lock_add_to_lru(struct ldlm_lock *lock)
 231 {
 232         struct ldlm_namespace *ns = ldlm_lock_to_ns(lock);
 233
 234         ENTRY;
 235         cfs_spin_lock(&ns->ns_unused_lock);
 236         ldlm_lock_add_to_lru_nolock(lock);
 237         cfs_spin_unlock(&ns->ns_unused_lock);
 238         EXIT;
 239 }
 240
 241 void ldlm_lock_touch_in_lru(struct ldlm_lock *lock)
 242 {
 243         struct ldlm_namespace *ns = ldlm_lock_to_ns(lock);
 244
 245         ENTRY;
 246         if (lock->l_ns_srv) {
 247                 LASSERT(cfs_list_empty(&lock->l_lru));
 248                 EXIT;
 249                 return;
 250         }
 251
 252         cfs_spin_lock(&ns->ns_unused_lock);
 253         if (!cfs_list_empty(&lock->l_lru)) {
 254                 ldlm_lock_remove_from_lru_nolock(lock);
 255                 ldlm_lock_add_to_lru_nolock(lock);
 256         }
 257         cfs_spin_unlock(&ns->ns_unused_lock);
 258         EXIT;
 259 }
 260
 261 /* This used to have a 'strict' flag, which recovery would use to mark an
 262  * in-use lock as needing-to-die.  Lest I am ever tempted to put it back, I
 263  * shall explain why it's gone: with the new hash table scheme, once you call
 264  * ldlm_lock_destroy, you can never drop your final references on this lock.
 265  * Because it's not in the hash table anymore.  -phil */
 266 int ldlm_lock_destroy_internal(struct ldlm_lock *lock)
 267 {
 268         ENTRY;
 269
 270         if (lock->l_readers || lock->l_writers) {
 271                 LDLM_ERROR(lock, "lock still has references");
 272                 ldlm_lock_dump(D_ERROR, lock, 0);
 273                 LBUG();
 274         }
 275
 276         if (!cfs_list_empty(&lock->l_res_link)) {
 277                 LDLM_ERROR(lock, "lock still on resource");
 278                 ldlm_lock_dump(D_ERROR, lock, 0);
 279                 LBUG();
 280         }
 281
 282         if (lock->l_destroyed) {
 283                 LASSERT(cfs_list_empty(&lock->l_lru));
 284                 EXIT;
 285                 return 0;
 286         }
 287         lock->l_destroyed = 1;
 288
 289         if (lock->l_export && lock->l_export->exp_lock_hash &&
 290             !cfs_hlist_unhashed(&lock->l_exp_hash))
 291                 cfs_hash_del(lock->l_export->exp_lock_hash,
 292                              &lock->l_remote_handle, &lock->l_exp_hash);
 293
 294         ldlm_lock_remove_from_lru(lock);
 295         class_handle_unhash(&lock->l_handle);
 296
 297 #if 0
 298         /* Wake anyone waiting for this lock */
 299         /* FIXME: I should probably add yet another flag, instead of using
 300          * l_export to only call this on clients */
 301         if (lock->l_export)
 302                 class_export_put(lock->l_export);
 303         lock->l_export = NULL;
 304         if (lock->l_export && lock->l_completion_ast)
 305                 lock->l_completion_ast(lock, 0);
 306 #endif
 307         EXIT;
 308         return 1;
 309 }
 310
 311 void ldlm_lock_destroy(struct ldlm_lock *lock)
 312 {
 313         int first;
 314         ENTRY;
 315         lock_res_and_lock(lock);
 316         first = ldlm_lock_destroy_internal(lock);
 317         unlock_res_and_lock(lock);
 318
 319         /* drop reference from hashtable only for first destroy */
 320         if (first) {
 321                 lu_ref_del(&lock->l_reference, "hash", lock);
 322                 LDLM_LOCK_RELEASE(lock);
 323         }
 324         EXIT;
 325 }
 326
 327 void ldlm_lock_destroy_nolock(struct ldlm_lock *lock)
 328 {
 329         int first;
 330         ENTRY;
 331         first = ldlm_lock_destroy_internal(lock);
 332         /* drop reference from hashtable only for first destroy */
 333         if (first) {
 334                 lu_ref_del(&lock->l_reference, "hash", lock);
 335                 LDLM_LOCK_RELEASE(lock);
 336         }
 337         EXIT;
 338 }
 339
 340 /* this is called by portals_handle2object with the handle lock taken */
 341 static void lock_handle_addref(void *lock)
 342 {
 343         LDLM_LOCK_GET((struct ldlm_lock *)lock);
 344 }
 345
 346 /*
 347  * usage: pass in a resource on which you have done ldlm_resource_get
 348  *        new lock will take over the refcount.
 349  * returns: lock with refcount 2 - one for current caller and one for remote
 350  */
 351 static struct ldlm_lock *ldlm_lock_new(struct ldlm_resource *resource)
 352 {
 353         struct ldlm_lock *lock;
 354         ENTRY;
 355
 356         if (resource == NULL)
 357                 LBUG();
 358
 359         OBD_SLAB_ALLOC_PTR_GFP(lock, ldlm_lock_slab, CFS_ALLOC_IO);
 360         if (lock == NULL)
 361                 RETURN(NULL);
 362
 363         cfs_spin_lock_init(&lock->l_lock);
 364         lock->l_resource = resource;
 365         lu_ref_add(&resource->lr_reference, "lock", lock);
 366
 367         cfs_atomic_set(&lock->l_refc, 2);
 368         CFS_INIT_LIST_HEAD(&lock->l_res_link);
 369         CFS_INIT_LIST_HEAD(&lock->l_lru);
 370         CFS_INIT_LIST_HEAD(&lock->l_pending_chain);
 371         CFS_INIT_LIST_HEAD(&lock->l_bl_ast);
 372         CFS_INIT_LIST_HEAD(&lock->l_cp_ast);
 373         CFS_INIT_LIST_HEAD(&lock->l_rk_ast);
 374         cfs_waitq_init(&lock->l_waitq);
 375         lock->l_blocking_lock = NULL;
 376         CFS_INIT_LIST_HEAD(&lock->l_sl_mode);
 377         CFS_INIT_LIST_HEAD(&lock->l_sl_policy);
 378         CFS_INIT_HLIST_NODE(&lock->l_exp_hash);
 379
 380         cfs_atomic_inc(&ldlm_res_to_ns(resource)->ns_locks);
 381         CFS_INIT_LIST_HEAD(&lock->l_handle.h_link);
 382         class_handle_hash(&lock->l_handle, lock_handle_addref);
 383
 384         lu_ref_init(&lock->l_reference);
 385         lu_ref_add(&lock->l_reference, "hash", lock);
 386         lock->l_callback_timeout = 0;
 387
 388 #if LUSTRE_TRACKS_LOCK_EXP_REFS
 389         CFS_INIT_LIST_HEAD(&lock->l_exp_refs_link);
 390         lock->l_exp_refs_nr = 0;
 391         lock->l_exp_refs_target = NULL;
 392 #endif
 393
 394         RETURN(lock);
 395 }
 396
 397 int ldlm_lock_change_resource(struct ldlm_namespace *ns, struct ldlm_lock *lock,
 398                               const struct ldlm_res_id *new_resid)
 399 {
 400         struct ldlm_resource *oldres = lock->l_resource;
 401         struct ldlm_resource *newres;
 402         int type;
 403         ENTRY;
 404
 405         LASSERT(ns_is_client(ns));
 406
 407         lock_res_and_lock(lock);
 408         if (memcmp(new_resid, &lock->l_resource->lr_name,
 409                    sizeof(lock->l_resource->lr_name)) == 0) {
 410                 /* Nothing to do */
 411                 unlock_res_and_lock(lock);
 412                 RETURN(0);
 413         }
 414
 415         LASSERT(new_resid->name[0] != 0);
 416
 417         /* This function assumes that the lock isn't on any lists */
 418         LASSERT(cfs_list_empty(&lock->l_res_link));
 419
 420         type = oldres->lr_type;
 421         unlock_res_and_lock(lock);
 422
 423         newres = ldlm_resource_get(ns, NULL, new_resid, type, 1);
 424         lu_ref_add(&newres->lr_reference, "lock", lock);
 425         if (newres == NULL)
 426                 RETURN(-ENOMEM);
 427         /*
 428          * To flip the lock from the old to the new resource, lock, oldres and
 429          * newres have to be locked. Resource spin-locks are nested within
 430          * lock->l_lock, and are taken in the memory address order to avoid
 431          * dead-locks.
 432          */
 433         cfs_spin_lock(&lock->l_lock);
 434         oldres = lock->l_resource;
 435         if (oldres < newres) {
 436                 lock_res(oldres);
 437                 lock_res_nested(newres, LRT_NEW);
 438         } else {
 439                 lock_res(newres);
 440                 lock_res_nested(oldres, LRT_NEW);
 441         }
 442         LASSERT(memcmp(new_resid, &oldres->lr_name,
 443                        sizeof oldres->lr_name) != 0);
 444         lock->l_resource = newres;
 445         unlock_res(oldres);
 446         unlock_res_and_lock(lock);
 447
 448         /* ...and the flowers are still standing! */
 449         lu_ref_del(&oldres->lr_reference, "lock", lock);
 450         ldlm_resource_putref(oldres);
 451
 452         RETURN(0);
 453 }
 454
 455 /*
 456  *  HANDLES
 457  */
 458
 459 void ldlm_lock2handle(const struct ldlm_lock *lock, struct lustre_handle *lockh)
 460 {
 461         lockh->cookie = lock->l_handle.h_cookie;
 462 }
 463
 464 /* if flags: atomically get the lock and set the flags.
 465  *           Return NULL if flag already set
 466  */
 467
 468 struct ldlm_lock *__ldlm_handle2lock(const struct lustre_handle *handle,
 469                                      int flags)
 470 {
 471         struct ldlm_namespace *ns;
 472         struct ldlm_lock *lock, *retval = NULL;
 473         ENTRY;
 474
 475         LASSERT(handle);
 476
 477         lock = class_handle2object(handle->cookie);
 478         if (lock == NULL)
 479                 RETURN(NULL);
 480
 481         LASSERT(lock->l_resource != NULL);
 482         ns = ldlm_lock_to_ns(lock);
 483         LASSERT(ns != NULL);
 484
 485         lu_ref_add_atomic(&lock->l_reference, "handle", cfs_current());
 486         lock_res_and_lock(lock);
 487
 488         /* It's unlikely but possible that someone marked the lock as
 489          * destroyed after we did handle2object on it */
 490         if (lock->l_destroyed) {
 491                 unlock_res_and_lock(lock);
 492                 CDEBUG(D_INFO, "lock already destroyed: lock %p\n", lock);
 493                 LDLM_LOCK_PUT(lock);
 494                 GOTO(out, retval);
 495         }
 496
 497         if (flags && (lock->l_flags & flags)) {
 498                 unlock_res_and_lock(lock);
 499                 LDLM_LOCK_PUT(lock);
 500                 GOTO(out, retval);
 501         }
 502
 503         if (flags)
 504                 lock->l_flags |= flags;
 505
 506         unlock_res_and_lock(lock);
 507         retval = lock;
 508         EXIT;
 509  out:
 510         return retval;
 511 }
 512
 513 void ldlm_lock2desc(struct ldlm_lock *lock, struct ldlm_lock_desc *desc)
 514 {
 515         struct obd_export *exp = lock->l_export?:lock->l_conn_export;
 516         /* INODEBITS_INTEROP: If the other side does not support
 517          * inodebits, reply with a plain lock descriptor.
 518          */
 519         if ((lock->l_resource->lr_type == LDLM_IBITS) &&
 520             (exp && !(exp->exp_connect_flags & OBD_CONNECT_IBITS))) {
 521                 /* Make sure all the right bits are set in this lock we
 522                    are going to pass to client */
 523                 LASSERTF(lock->l_policy_data.l_inodebits.bits ==
 524                          (MDS_INODELOCK_LOOKUP|MDS_INODELOCK_UPDATE),
 525                          "Inappropriate inode lock bits during "
 526                          "conversion " LPU64 "\n",
 527                          lock->l_policy_data.l_inodebits.bits);
 528
 529                 ldlm_res2desc(lock->l_resource, &desc->l_resource);
 530                 desc->l_resource.lr_type = LDLM_PLAIN;
 531
 532                 /* Convert "new" lock mode to something old client can
 533                    understand */
 534                 if ((lock->l_req_mode == LCK_CR) ||
 535                     (lock->l_req_mode == LCK_CW))
 536                         desc->l_req_mode = LCK_PR;
 537                 else
 538                         desc->l_req_mode = lock->l_req_mode;
 539                 if ((lock->l_granted_mode == LCK_CR) ||
 540                     (lock->l_granted_mode == LCK_CW)) {
 541                         desc->l_granted_mode = LCK_PR;
 542                 } else {
 543                         /* We never grant PW/EX locks to clients */
 544                         LASSERT((lock->l_granted_mode != LCK_PW) &&
 545                                 (lock->l_granted_mode != LCK_EX));
 546                         desc->l_granted_mode = lock->l_granted_mode;
 547                 }
 548
 549                 /* We do not copy policy here, because there is no
 550                    policy for plain locks */
 551         } else {
 552                 ldlm_res2desc(lock->l_resource, &desc->l_resource);
 553                 desc->l_req_mode = lock->l_req_mode;
 554                 desc->l_granted_mode = lock->l_granted_mode;
 555                 desc->l_policy_data = lock->l_policy_data;
 556         }
 557 }
 558
 559 void ldlm_add_bl_work_item(struct ldlm_lock *lock, struct ldlm_lock *new,
 560                            cfs_list_t *work_list)
 561 {
 562         if ((lock->l_flags & LDLM_FL_AST_SENT) == 0) {
 563                 LDLM_DEBUG(lock, "lock incompatible; sending blocking AST.");
 564                 lock->l_flags |= LDLM_FL_AST_SENT;
 565                 /* If the enqueuing client said so, tell the AST recipient to
 566                  * discard dirty data, rather than writing back. */
 567                 if (new->l_flags & LDLM_AST_DISCARD_DATA)
 568                         lock->l_flags |= LDLM_FL_DISCARD_DATA;
 569                 LASSERT(cfs_list_empty(&lock->l_bl_ast));
 570                 cfs_list_add(&lock->l_bl_ast, work_list);
 571                 LDLM_LOCK_GET(lock);
 572                 LASSERT(lock->l_blocking_lock == NULL);
 573                 lock->l_blocking_lock = LDLM_LOCK_GET(new);
 574         }
 575 }
 576
 577 void ldlm_add_cp_work_item(struct ldlm_lock *lock, cfs_list_t *work_list)
 578 {
 579         if ((lock->l_flags & LDLM_FL_CP_REQD) == 0) {
 580                 lock->l_flags |= LDLM_FL_CP_REQD;
 581                 LDLM_DEBUG(lock, "lock granted; sending completion AST.");
 582                 LASSERT(cfs_list_empty(&lock->l_cp_ast));
 583                 cfs_list_add(&lock->l_cp_ast, work_list);
 584                 LDLM_LOCK_GET(lock);
 585         }
 586 }
 587
 588 /* must be called with lr_lock held */
 589 void ldlm_add_ast_work_item(struct ldlm_lock *lock, struct ldlm_lock *new,
 590                             cfs_list_t *work_list)
 591 {
 592         ENTRY;
 593         check_res_locked(lock->l_resource);
 594         if (new)
 595                 ldlm_add_bl_work_item(lock, new, work_list);
 596         else
 597                 ldlm_add_cp_work_item(lock, work_list);
 598         EXIT;
 599 }
 600
 601 void ldlm_lock_addref(struct lustre_handle *lockh, __u32 mode)
 602 {
 603         struct ldlm_lock *lock;
 604
 605         lock = ldlm_handle2lock(lockh);
 606         LASSERT(lock != NULL);
 607         ldlm_lock_addref_internal(lock, mode);
 608         LDLM_LOCK_PUT(lock);
 609 }
 610
 611 void ldlm_lock_addref_internal_nolock(struct ldlm_lock *lock, __u32 mode)
 612 {
 613         ldlm_lock_remove_from_lru(lock);
 614         if (mode & (LCK_NL | LCK_CR | LCK_PR)) {
 615                 lock->l_readers++;
 616                 lu_ref_add_atomic(&lock->l_reference, "reader", lock);
 617         }
 618         if (mode & (LCK_EX | LCK_CW | LCK_PW | LCK_GROUP | LCK_COS)) {
 619                 lock->l_writers++;
 620                 lu_ref_add_atomic(&lock->l_reference, "writer", lock);
 621         }
 622         LDLM_LOCK_GET(lock);
 623         lu_ref_add_atomic(&lock->l_reference, "user", lock);
 624         LDLM_DEBUG(lock, "ldlm_lock_addref(%s)", ldlm_lockname[mode]);
 625 }
 626
 627 /**
 628  * Attempts to addref a lock, and fails if lock is already LDLM_FL_CBPENDING
 629  * or destroyed.
 630  *
 631  * \retval 0 success, lock was addref-ed
 632  *
 633  * \retval -EAGAIN lock is being canceled.
 634  */
 635 int ldlm_lock_addref_try(struct lustre_handle *lockh, __u32 mode)
 636 {
 637         struct ldlm_lock *lock;
 638         int               result;
 639
 640         result = -EAGAIN;
 641         lock = ldlm_handle2lock(lockh);
 642         if (lock != NULL) {
 643                 lock_res_and_lock(lock);
 644                 if (lock->l_readers != 0 || lock->l_writers != 0 ||
 645                     !(lock->l_flags & LDLM_FL_CBPENDING)) {
 646                         ldlm_lock_addref_internal_nolock(lock, mode);
 647                         result = 0;
 648                 }
 649                 unlock_res_and_lock(lock);
 650                 LDLM_LOCK_PUT(lock);
 651         }
 652         return result;
 653 }
 654
 655 /* only called for local locks */
 656 void ldlm_lock_addref_internal(struct ldlm_lock *lock, __u32 mode)
 657 {
 658         lock_res_and_lock(lock);
 659         ldlm_lock_addref_internal_nolock(lock, mode);
 660         unlock_res_and_lock(lock);
 661 }
 662
 663 /* only called in ldlm_flock_destroy and for local locks.
 664  *  * for LDLM_FLOCK type locks, l_blocking_ast is null, and
 665  *   * ldlm_lock_remove_from_lru() does nothing, it is safe
 666  *    * for ldlm_flock_destroy usage by dropping some code */
 667 void ldlm_lock_decref_internal_nolock(struct ldlm_lock *lock, __u32 mode)
 668 {
 669         LDLM_DEBUG(lock, "ldlm_lock_decref(%s)", ldlm_lockname[mode]);
 670         if (mode & (LCK_NL | LCK_CR | LCK_PR)) {
 671                 LASSERT(lock->l_readers > 0);
 672                 lu_ref_del(&lock->l_reference, "reader", lock);
 673                 lock->l_readers--;
 674         }
 675         if (mode & (LCK_EX | LCK_CW | LCK_PW | LCK_GROUP | LCK_COS)) {
 676                 LASSERT(lock->l_writers > 0);
 677                 lu_ref_del(&lock->l_reference, "writer", lock);
 678                 lock->l_writers--;
 679         }
 680
 681         lu_ref_del(&lock->l_reference, "user", lock);
 682         LDLM_LOCK_RELEASE(lock);    /* matches the LDLM_LOCK_GET() in addref */
 683 }
 684
 685 void ldlm_lock_decref_internal(struct ldlm_lock *lock, __u32 mode)
 686 {
 687         struct ldlm_namespace *ns;
 688         ENTRY;
 689
 690         lock_res_and_lock(lock);
 691
 692         ns = ldlm_lock_to_ns(lock);
 693
 694         ldlm_lock_decref_internal_nolock(lock, mode);
 695
 696         if (lock->l_flags & LDLM_FL_LOCAL &&
 697             !lock->l_readers && !lock->l_writers) {
 698                 /* If this is a local lock on a server namespace and this was
 699                  * the last reference, cancel the lock. */
 700                 CDEBUG(D_INFO, "forcing cancel of local lock\n");
 701                 lock->l_flags |= LDLM_FL_CBPENDING;
 702         }
 703
 704         if (!lock->l_readers && !lock->l_writers &&
 705             (lock->l_flags & LDLM_FL_CBPENDING)) {
 706                 /* If we received a blocked AST and this was the last reference,
 707                  * run the callback. */
 708                 if (lock->l_ns_srv && lock->l_export)
 709                         CERROR("FL_CBPENDING set on non-local lock--just a "
 710                                "warning\n");
 711
 712                 LDLM_DEBUG(lock, "final decref done on cbpending lock");
 713
 714                 LDLM_LOCK_GET(lock); /* dropped by bl thread */
 715                 ldlm_lock_remove_from_lru(lock);
 716                 unlock_res_and_lock(lock);
 717
 718                 if (lock->l_flags & LDLM_FL_FAIL_LOC)
 719                         OBD_RACE(OBD_FAIL_LDLM_CP_BL_RACE);
 720
 721                 if ((lock->l_flags & LDLM_FL_ATOMIC_CB) ||
 722                     ldlm_bl_to_thread_lock(ns, NULL, lock) != 0)
 723                         ldlm_handle_bl_callback(ns, NULL, lock);
 724         } else if (ns_is_client(ns) &&
 725                    !lock->l_readers && !lock->l_writers &&
 726                    !(lock->l_flags & LDLM_FL_BL_AST)) {
 727                 /* If this is a client-side namespace and this was the last
 728                  * reference, put it on the LRU. */
 729                 ldlm_lock_add_to_lru(lock);
 730                 unlock_res_and_lock(lock);
 731
 732                 if (lock->l_flags & LDLM_FL_FAIL_LOC)
 733                         OBD_RACE(OBD_FAIL_LDLM_CP_BL_RACE);
 734
 735                 /* Call ldlm_cancel_lru() only if EARLY_CANCEL and LRU RESIZE
 736                  * are not supported by the server, otherwise, it is done on
 737                  * enqueue. */
 738                 if (!exp_connect_cancelset(lock->l_conn_export) &&
 739                     !ns_connect_lru_resize(ns))
 740                         ldlm_cancel_lru(ns, 0, LDLM_ASYNC, 0);
 741         } else {
 742                 unlock_res_and_lock(lock);
 743         }
 744
 745         EXIT;
 746 }
 747
 748 void ldlm_lock_decref(struct lustre_handle *lockh, __u32 mode)
 749 {
 750         struct ldlm_lock *lock = __ldlm_handle2lock(lockh, 0);
 751         LASSERTF(lock != NULL, "Non-existing lock: "LPX64"\n", lockh->cookie);
 752         ldlm_lock_decref_internal(lock, mode);
 753         LDLM_LOCK_PUT(lock);
 754 }
 755
 756 /* This will drop a lock reference and mark it for destruction, but will not
 757  * necessarily cancel the lock before returning. */
 758 void ldlm_lock_decref_and_cancel(struct lustre_handle *lockh, __u32 mode)
 759 {
 760         struct ldlm_lock *lock = __ldlm_handle2lock(lockh, 0);
 761         ENTRY;
 762
 763         LASSERT(lock != NULL);
 764
 765         LDLM_DEBUG(lock, "ldlm_lock_decref(%s)", ldlm_lockname[mode]);
 766         lock_res_and_lock(lock);
 767         lock->l_flags |= LDLM_FL_CBPENDING;
 768         unlock_res_and_lock(lock);
 769         ldlm_lock_decref_internal(lock, mode);
 770         LDLM_LOCK_PUT(lock);
 771 }
 772
 773 struct sl_insert_point {
 774         cfs_list_t *res_link;
 775         cfs_list_t *mode_link;
 776         cfs_list_t *policy_link;
 777 };
 778
 779 /*
 780  * search_granted_lock
 781  *
 782  * Description:
 783  *      Finds a position to insert the new lock.
 784  * Parameters:
 785  *      queue [input]:  the granted list where search acts on;
 786  *      req [input]:    the lock whose position to be located;
 787  *      prev [output]:  positions within 3 lists to insert @req to
 788  * Return Value:
 789  *      filled @prev
 790  * NOTE: called by
 791  *  - ldlm_grant_lock_with_skiplist
 792  */
 793 static void search_granted_lock(cfs_list_t *queue,
 794                                 struct ldlm_lock *req,
 795                                 struct sl_insert_point *prev)
 796 {
 797         cfs_list_t *tmp;
 798         struct ldlm_lock *lock, *mode_end, *policy_end;
 799         ENTRY;
 800
 801         cfs_list_for_each(tmp, queue) {
 802                 lock = cfs_list_entry(tmp, struct ldlm_lock, l_res_link);
 803
 804                 mode_end = cfs_list_entry(lock->l_sl_mode.prev,
 805                                           struct ldlm_lock, l_sl_mode);
 806
 807                 if (lock->l_req_mode != req->l_req_mode) {
 808                         /* jump to last lock of mode group */
 809                         tmp = &mode_end->l_res_link;
 810                         continue;
 811                 }
 812
 813                 /* suitable mode group is found */
 814                 if (lock->l_resource->lr_type == LDLM_PLAIN) {
 815                         /* insert point is last lock of the mode group */
 816                         prev->res_link = &mode_end->l_res_link;
 817                         prev->mode_link = &mode_end->l_sl_mode;
 818                         prev->policy_link = &req->l_sl_policy;
 819                         EXIT;
 820                         return;
 821                 } else if (lock->l_resource->lr_type == LDLM_IBITS) {
 822                         for (;;) {
 823                                 policy_end =
 824                                         cfs_list_entry(lock->l_sl_policy.prev,
 825                                                        struct ldlm_lock,
 826                                                        l_sl_policy);
 827
 828                                 if (lock->l_policy_data.l_inodebits.bits ==
 829                                     req->l_policy_data.l_inodebits.bits) {
 830                                         /* insert point is last lock of
 831                                          * the policy group */
 832                                         prev->res_link =
 833                                                 &policy_end->l_res_link;
 834                                         prev->mode_link =
 835                                                 &policy_end->l_sl_mode;
 836                                         prev->policy_link =
 837                                                 &policy_end->l_sl_policy;
 838                                         EXIT;
 839                                         return;
 840                                 }
 841
 842                                 if (policy_end == mode_end)
 843                                         /* done with mode group */
 844                                         break;
 845
 846                                 /* go to next policy group within mode group */
 847                                 tmp = policy_end->l_res_link.next;
 848                                 lock = cfs_list_entry(tmp, struct ldlm_lock,
 849                                                       l_res_link);
 850                         }  /* loop over policy groups within the mode group */
 851
 852                         /* insert point is last lock of the mode group,
 853                          * new policy group is started */
 854                         prev->res_link = &mode_end->l_res_link;
 855                         prev->mode_link = &mode_end->l_sl_mode;
 856                         prev->policy_link = &req->l_sl_policy;
 857                         EXIT;
 858                         return;
 859                 } else {
 860                         LDLM_ERROR(lock,"is not LDLM_PLAIN or LDLM_IBITS lock");
 861                         LBUG();
 862                 }
 863         }
 864
 865         /* insert point is last lock on the queue,
 866          * new mode group and new policy group are started */
 867         prev->res_link = queue->prev;
 868         prev->mode_link = &req->l_sl_mode;
 869         prev->policy_link = &req->l_sl_policy;
 870         EXIT;
 871         return;
 872 }
 873
 874 static void ldlm_granted_list_add_lock(struct ldlm_lock *lock,
 875                                        struct sl_insert_point *prev)
 876 {
 877         struct ldlm_resource *res = lock->l_resource;
 878         ENTRY;
 879
 880         check_res_locked(res);
 881
 882         ldlm_resource_dump(D_INFO, res);
 883         CDEBUG(D_OTHER, "About to add this lock:\n");
 884         ldlm_lock_dump(D_OTHER, lock, 0);
 885
 886         if (lock->l_destroyed) {
 887                 CDEBUG(D_OTHER, "Lock destroyed, not adding to resource\n");
 888                 return;
 889         }
 890
 891         LASSERT(cfs_list_empty(&lock->l_res_link));
 892         LASSERT(cfs_list_empty(&lock->l_sl_mode));
 893         LASSERT(cfs_list_empty(&lock->l_sl_policy));
 894
 895         cfs_list_add(&lock->l_res_link, prev->res_link);
 896         cfs_list_add(&lock->l_sl_mode, prev->mode_link);
 897         cfs_list_add(&lock->l_sl_policy, prev->policy_link);
 898
 899         EXIT;
 900 }
 901
 902 static void ldlm_grant_lock_with_skiplist(struct ldlm_lock *lock)
 903 {
 904         struct sl_insert_point prev;
 905         ENTRY;
 906
 907         LASSERT(lock->l_req_mode == lock->l_granted_mode);
 908
 909         search_granted_lock(&lock->l_resource->lr_granted, lock, &prev);
 910         ldlm_granted_list_add_lock(lock, &prev);
 911         EXIT;
 912 }
 913
 914 /* NOTE: called by
 915  *  - ldlm_lock_enqueue
 916  *  - ldlm_reprocess_queue
 917  *  - ldlm_lock_convert
 918  *
 919  * must be called with lr_lock held
 920  */
 921 void ldlm_grant_lock(struct ldlm_lock *lock, cfs_list_t *work_list)
 922 {
 923         struct ldlm_resource *res = lock->l_resource;
 924         ENTRY;
 925
 926         check_res_locked(res);
 927
 928         lock->l_granted_mode = lock->l_req_mode;
 929         if (res->lr_type == LDLM_PLAIN || res->lr_type == LDLM_IBITS)
 930                 ldlm_grant_lock_with_skiplist(lock);
 931         else if (res->lr_type == LDLM_EXTENT)
 932                 ldlm_extent_add_lock(res, lock);
 933         else
 934                 ldlm_resource_add_lock(res, &res->lr_granted, lock);
 935
 936         if (lock->l_granted_mode < res->lr_most_restr)
 937                 res->lr_most_restr = lock->l_granted_mode;
 938
 939         if (work_list && lock->l_completion_ast != NULL)
 940                 ldlm_add_ast_work_item(lock, NULL, work_list);
 941
 942         ldlm_pool_add(&ldlm_res_to_ns(res)->ns_pool, lock);
 943         EXIT;
 944 }
 945
 946 /* returns a referenced lock or NULL.  See the flag descriptions below, in the
 947  * comment above ldlm_lock_match */
 948 static struct ldlm_lock *search_queue(cfs_list_t *queue,
 949                                       ldlm_mode_t *mode,
 950                                       ldlm_policy_data_t *policy,
 951                                       struct ldlm_lock *old_lock,
 952                                       int flags, int unref)
 953 {
 954         struct ldlm_lock *lock;
 955         cfs_list_t       *tmp;
 956
 957         cfs_list_for_each(tmp, queue) {
 958                 ldlm_mode_t match;
 959
 960                 lock = cfs_list_entry(tmp, struct ldlm_lock, l_res_link);
 961
 962                 if (lock == old_lock)
 963                         break;
 964
 965                 /* llite sometimes wants to match locks that will be
 966                  * canceled when their users drop, but we allow it to match
 967                  * if it passes in CBPENDING and the lock still has users.
 968                  * this is generally only going to be used by children
 969                  * whose parents already hold a lock so forward progress
 970                  * can still happen. */
 971                 if (lock->l_flags & LDLM_FL_CBPENDING &&
 972                     !(flags & LDLM_FL_CBPENDING))
 973                         continue;
 974                 if (!unref && lock->l_flags & LDLM_FL_CBPENDING &&
 975                     lock->l_readers == 0 && lock->l_writers == 0)
 976                         continue;
 977
 978                 if (!(lock->l_req_mode & *mode))
 979                         continue;
 980                 match = lock->l_req_mode;
 981
 982                 if (lock->l_resource->lr_type == LDLM_EXTENT &&
 983                     (lock->l_policy_data.l_extent.start >
 984                      policy->l_extent.start ||
 985                      lock->l_policy_data.l_extent.end < policy->l_extent.end))
 986                         continue;
 987
 988                 if (unlikely(match == LCK_GROUP) &&
 989                     lock->l_resource->lr_type == LDLM_EXTENT &&
 990                     lock->l_policy_data.l_extent.gid != policy->l_extent.gid)
 991                         continue;
 992
 993                 /* We match if we have existing lock with same or wider set
 994                    of bits. */
 995                 if (lock->l_resource->lr_type == LDLM_IBITS &&
 996                      ((lock->l_policy_data.l_inodebits.bits &
 997                       policy->l_inodebits.bits) !=
 998                       policy->l_inodebits.bits))
 999                         continue;
1000
1001                 if (!unref &&
1002                     (lock->l_destroyed || (lock->l_flags & LDLM_FL_FAILED)))
1003                         continue;
1004
1005                 if ((flags & LDLM_FL_LOCAL_ONLY) &&
1006                     !(lock->l_flags & LDLM_FL_LOCAL))
1007                         continue;
1008
1009                 if (flags & LDLM_FL_TEST_LOCK) {
1010                         LDLM_LOCK_GET(lock);
1011                         ldlm_lock_touch_in_lru(lock);
1012                 } else {
1013                         ldlm_lock_addref_internal_nolock(lock, match);
1014                 }
1015                 *mode = match;
1016                 return lock;
1017         }
1018
1019         return NULL;
1020 }
1021
1022 void ldlm_lock_allow_match_locked(struct ldlm_lock *lock)
1023 {
1024         lock->l_flags |= LDLM_FL_LVB_READY;
1025         cfs_waitq_signal(&lock->l_waitq);
1026 }
1027
1028 void ldlm_lock_allow_match(struct ldlm_lock *lock)
1029 {
1030         lock_res_and_lock(lock);
1031         ldlm_lock_allow_match_locked(lock);
1032         unlock_res_and_lock(lock);
1033 }
1034
1035 /* Can be called in two ways:
1036  *
1037  * If 'ns' is NULL, then lockh describes an existing lock that we want to look
1038  * for a duplicate of.
1039  *
1040  * Otherwise, all of the fields must be filled in, to match against.
1041  *
1042  * If 'flags' contains LDLM_FL_LOCAL_ONLY, then only match local locks on the
1043  *     server (ie, connh is NULL)
1044  * If 'flags' contains LDLM_FL_BLOCK_GRANTED, then only locks on the granted
1045  *     list will be considered
1046  * If 'flags' contains LDLM_FL_CBPENDING, then locks that have been marked
1047  *     to be canceled can still be matched as long as they still have reader
1048  *     or writer refernces
1049  * If 'flags' contains LDLM_FL_TEST_LOCK, then don't actually reference a lock,
1050  *     just tell us if we would have matched.
1051  *
1052  * Returns 1 if it finds an already-existing lock that is compatible; in this
1053  * case, lockh is filled in with a addref()ed lock
1054  *
1055  * we also check security context, if that failed we simply return 0 (to keep
1056  * caller code unchanged), the context failure will be discovered by caller
1057  * sometime later.
1058  */
1059 ldlm_mode_t ldlm_lock_match(struct ldlm_namespace *ns, int flags,
1060                             const struct ldlm_res_id *res_id, ldlm_type_t type,
1061                             ldlm_policy_data_t *policy, ldlm_mode_t mode,
1062                             struct lustre_handle *lockh, int unref)
1063 {
1064         struct ldlm_resource *res;
1065         struct ldlm_lock *lock, *old_lock = NULL;
1066         int rc = 0;
1067         ENTRY;
1068
1069         if (ns == NULL) {
1070                 old_lock = ldlm_handle2lock(lockh);
1071                 LASSERT(old_lock);
1072
1073                 ns = ldlm_lock_to_ns(old_lock);
1074                 res_id = &old_lock->l_resource->lr_name;
1075                 type = old_lock->l_resource->lr_type;
1076                 mode = old_lock->l_req_mode;
1077         }
1078
1079         res = ldlm_resource_get(ns, NULL, res_id, type, 0);
1080         if (res == NULL) {
1081                 LASSERT(old_lock == NULL);
1082                 RETURN(0);
1083         }
1084
1085         LDLM_RESOURCE_ADDREF(res);
1086         lock_res(res);
1087
1088         lock = search_queue(&res->lr_granted, &mode, policy, old_lock,
1089                             flags, unref);
1090         if (lock != NULL)
1091                 GOTO(out, rc = 1);
1092         if (flags & LDLM_FL_BLOCK_GRANTED)
1093                 GOTO(out, rc = 0);
1094         lock = search_queue(&res->lr_converting, &mode, policy, old_lock,
1095                             flags, unref);
1096         if (lock != NULL)
1097                 GOTO(out, rc = 1);
1098         lock = search_queue(&res->lr_waiting, &mode, policy, old_lock,
1099                             flags, unref);
1100         if (lock != NULL)
1101                 GOTO(out, rc = 1);
1102
1103         EXIT;
1104  out:
1105         unlock_res(res);
1106         LDLM_RESOURCE_DELREF(res);
1107         ldlm_resource_putref(res);
1108
1109         if (lock) {
1110                 ldlm_lock2handle(lock, lockh);
1111                 if ((flags & LDLM_FL_LVB_READY) &&
1112                     (!(lock->l_flags & LDLM_FL_LVB_READY))) {
1113                         struct l_wait_info lwi;
1114                         if (lock->l_completion_ast) {
1115                                 int err = lock->l_completion_ast(lock,
1116                                                           LDLM_FL_WAIT_NOREPROC,
1117                                                                  NULL);
1118                                 if (err) {
1119                                         if (flags & LDLM_FL_TEST_LOCK)
1120                                                 LDLM_LOCK_RELEASE(lock);
1121                                         else
1122                                                 ldlm_lock_decref_internal(lock,
1123                                                                           mode);
1124                                         rc = 0;
1125                                         goto out2;
1126                                 }
1127                         }
1128
1129                         lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(obd_timeout),
1130                                                NULL, LWI_ON_SIGNAL_NOOP, NULL);
1131
1132                         /* XXX FIXME see comment on CAN_MATCH in lustre_dlm.h */
1133                         l_wait_event(lock->l_waitq,
1134                                      (lock->l_flags & LDLM_FL_LVB_READY), &lwi);
1135                 }
1136         }
1137  out2:
1138         if (rc) {
1139                 LDLM_DEBUG(lock, "matched ("LPU64" "LPU64")",
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                 /* check user's security context */
1146                 if (lock->l_conn_export &&
1147                     sptlrpc_import_check_ctx(
1148                                 class_exp2cliimp(lock->l_conn_export))) {
1149                         if (!(flags & LDLM_FL_TEST_LOCK))
1150                                 ldlm_lock_decref_internal(lock, mode);
1151                         rc = 0;
1152                 }
1153
1154                 if (flags & LDLM_FL_TEST_LOCK)
1155                         LDLM_LOCK_RELEASE(lock);
1156
1157         } else if (!(flags & LDLM_FL_TEST_LOCK)) {/*less verbose for test-only*/
1158                 LDLM_DEBUG_NOLOCK("not matched ns %p type %u mode %u res "
1159                                   LPU64"/"LPU64" ("LPU64" "LPU64")", ns,
1160                                   type, mode, res_id->name[0], res_id->name[1],
1161                                   (type == LDLM_PLAIN || type == LDLM_IBITS) ?
1162                                         res_id->name[2] :policy->l_extent.start,
1163                                   (type == LDLM_PLAIN || type == LDLM_IBITS) ?
1164                                         res_id->name[3] : policy->l_extent.end);
1165         }
1166         if (old_lock)
1167                 LDLM_LOCK_PUT(old_lock);
1168
1169         return rc ? mode : 0;
1170 }
1171
1172 /* Returns a referenced lock */
1173 struct ldlm_lock *ldlm_lock_create(struct ldlm_namespace *ns,
1174                                    const struct ldlm_res_id *res_id,
1175                                    ldlm_type_t type,
1176                                    ldlm_mode_t mode,
1177                                    const struct ldlm_callback_suite *cbs,
1178                                    void *data, __u32 lvb_len)
1179 {
1180         struct ldlm_lock *lock;
1181         struct ldlm_resource *res;
1182         ENTRY;
1183
1184         res = ldlm_resource_get(ns, NULL, res_id, type, 1);
1185         if (res == NULL)
1186                 RETURN(NULL);
1187
1188         lock = ldlm_lock_new(res);
1189
1190         if (lock == NULL)
1191                 RETURN(NULL);
1192
1193         lock->l_req_mode = mode;
1194         lock->l_ast_data = data;
1195         lock->l_pid = cfs_curproc_pid();
1196         lock->l_ns_srv = ns_is_server(ns);
1197         if (cbs) {
1198                 lock->l_blocking_ast = cbs->lcs_blocking;
1199                 lock->l_completion_ast = cbs->lcs_completion;
1200                 lock->l_glimpse_ast = cbs->lcs_glimpse;
1201                 lock->l_weigh_ast = cbs->lcs_weigh;
1202         }
1203
1204         lock->l_tree_node = NULL;
1205         /* if this is the extent lock, allocate the interval tree node */
1206         if (type == LDLM_EXTENT) {
1207                 if (ldlm_interval_alloc(lock) == NULL)
1208                         GOTO(out, 0);
1209         }
1210
1211         if (lvb_len) {
1212                 lock->l_lvb_len = lvb_len;
1213                 OBD_ALLOC(lock->l_lvb_data, lvb_len);
1214                 if (lock->l_lvb_data == NULL)
1215                         GOTO(out, 0);
1216         }
1217
1218         if (OBD_FAIL_CHECK(OBD_FAIL_LDLM_NEW_LOCK))
1219                 GOTO(out, 0);
1220
1221         RETURN(lock);
1222
1223 out:
1224         ldlm_lock_destroy(lock);
1225         LDLM_LOCK_RELEASE(lock);
1226         return NULL;
1227 }
1228
1229 ldlm_error_t ldlm_lock_enqueue(struct ldlm_namespace *ns,
1230                                struct ldlm_lock **lockp,
1231                                void *cookie, int *flags)
1232 {
1233         struct ldlm_lock *lock = *lockp;
1234         struct ldlm_resource *res = lock->l_resource;
1235         int local = ns_is_client(ldlm_res_to_ns(res));
1236         ldlm_processing_policy policy;
1237         ldlm_error_t rc = ELDLM_OK;
1238         struct ldlm_interval *node = NULL;
1239         ENTRY;
1240
1241         lock->l_last_activity = cfs_time_current_sec();
1242         /* policies are not executed on the client or during replay */
1243         if ((*flags & (LDLM_FL_HAS_INTENT|LDLM_FL_REPLAY)) == LDLM_FL_HAS_INTENT
1244             && !local && ns->ns_policy) {
1245                 rc = ns->ns_policy(ns, lockp, cookie, lock->l_req_mode, *flags,
1246                                    NULL);
1247                 if (rc == ELDLM_LOCK_REPLACED) {
1248                         /* The lock that was returned has already been granted,
1249                          * and placed into lockp.  If it's not the same as the
1250                          * one we passed in, then destroy the old one and our
1251                          * work here is done. */
1252                         if (lock != *lockp) {
1253                                 ldlm_lock_destroy(lock);
1254                                 LDLM_LOCK_RELEASE(lock);
1255                         }
1256                         *flags |= LDLM_FL_LOCK_CHANGED;
1257                         RETURN(0);
1258                 } else if (rc != ELDLM_OK ||
1259                            (rc == ELDLM_OK && (*flags & LDLM_FL_INTENT_ONLY))) {
1260                         ldlm_lock_destroy(lock);
1261                         RETURN(rc);
1262                 }
1263         }
1264
1265         /* For a replaying lock, it might be already in granted list. So
1266          * unlinking the lock will cause the interval node to be freed, we
1267          * have to allocate the interval node early otherwise we can't regrant
1268          * this lock in the future. - jay */
1269         if (!local && (*flags & LDLM_FL_REPLAY) && res->lr_type == LDLM_EXTENT)
1270                 OBD_SLAB_ALLOC_PTR_GFP(node, ldlm_interval_slab, CFS_ALLOC_IO);
1271
1272         lock_res_and_lock(lock);
1273         if (local && lock->l_req_mode == lock->l_granted_mode) {
1274                 /* The server returned a blocked lock, but it was granted
1275                  * before we got a chance to actually enqueue it.  We don't
1276                  * need to do anything else. */
1277                 *flags &= ~(LDLM_FL_BLOCK_GRANTED |
1278                             LDLM_FL_BLOCK_CONV | LDLM_FL_BLOCK_WAIT);
1279                 GOTO(out, ELDLM_OK);
1280         }
1281
1282         ldlm_resource_unlink_lock(lock);
1283         if (res->lr_type == LDLM_EXTENT && lock->l_tree_node == NULL) {
1284                 if (node == NULL) {
1285                         ldlm_lock_destroy_nolock(lock);
1286                         GOTO(out, rc = -ENOMEM);
1287                 }
1288
1289                 CFS_INIT_LIST_HEAD(&node->li_group);
1290                 ldlm_interval_attach(node, lock);
1291                 node = NULL;
1292         }
1293
1294         /* Some flags from the enqueue want to make it into the AST, via the
1295          * lock's l_flags. */
1296         lock->l_flags |= *flags & LDLM_AST_DISCARD_DATA;
1297
1298         /* This distinction between local lock trees is very important; a client
1299          * namespace only has information about locks taken by that client, and
1300          * thus doesn't have enough information to decide for itself if it can
1301          * be granted (below).  In this case, we do exactly what the server
1302          * tells us to do, as dictated by the 'flags'.
1303          *
1304          * We do exactly the same thing during recovery, when the server is
1305          * more or less trusting the clients not to lie.
1306          *
1307          * FIXME (bug 268): Detect obvious lies by checking compatibility in
1308          * granted/converting queues. */
1309         if (local) {
1310                 if (*flags & LDLM_FL_BLOCK_CONV)
1311                         ldlm_resource_add_lock(res, &res->lr_converting, lock);
1312                 else if (*flags & (LDLM_FL_BLOCK_WAIT | LDLM_FL_BLOCK_GRANTED))
1313                         ldlm_resource_add_lock(res, &res->lr_waiting, lock);
1314                 else
1315                         ldlm_grant_lock(lock, NULL);
1316                 GOTO(out, ELDLM_OK);
1317         } else if (*flags & LDLM_FL_REPLAY) {
1318                 if (*flags & LDLM_FL_BLOCK_CONV) {
1319                         ldlm_resource_add_lock(res, &res->lr_converting, lock);
1320                         GOTO(out, ELDLM_OK);
1321                 } else if (*flags & LDLM_FL_BLOCK_WAIT) {
1322                         ldlm_resource_add_lock(res, &res->lr_waiting, lock);
1323                         GOTO(out, ELDLM_OK);
1324                 } else if (*flags & LDLM_FL_BLOCK_GRANTED) {
1325                         ldlm_grant_lock(lock, NULL);
1326                         GOTO(out, ELDLM_OK);
1327                 }
1328                 /* If no flags, fall through to normal enqueue path. */
1329         }
1330
1331         policy = ldlm_processing_policy_table[res->lr_type];
1332         policy(lock, flags, 1, &rc, NULL);
1333         GOTO(out, rc);
1334 out:
1335         unlock_res_and_lock(lock);
1336         if (node)
1337                 OBD_SLAB_FREE(node, ldlm_interval_slab, sizeof(*node));
1338         return rc;
1339 }
1340
1341 /* Must be called with namespace taken: queue is waiting or converting. */
1342 int ldlm_reprocess_queue(struct ldlm_resource *res, cfs_list_t *queue,
1343                          cfs_list_t *work_list)
1344 {
1345         cfs_list_t *tmp, *pos;
1346         ldlm_processing_policy policy;
1347         int flags;
1348         int rc = LDLM_ITER_CONTINUE;
1349         ldlm_error_t err;
1350         ENTRY;
1351
1352         check_res_locked(res);
1353
1354         policy = ldlm_processing_policy_table[res->lr_type];
1355         LASSERT(policy);
1356
1357         cfs_list_for_each_safe(tmp, pos, queue) {
1358                 struct ldlm_lock *pending;
1359                 pending = cfs_list_entry(tmp, struct ldlm_lock, l_res_link);
1360
1361                 CDEBUG(D_INFO, "Reprocessing lock %p\n", pending);
1362
1363                 flags = 0;
1364                 rc = policy(pending, &flags, 0, &err, work_list);
1365                 if (rc != LDLM_ITER_CONTINUE)
1366                         break;
1367         }
1368
1369         RETURN(rc);
1370 }
1371
1372 /* Helper function for ldlm_run_ast_work().
1373  *
1374  * Send an existing rpc set specified by @arg->set and then
1375  * destroy it. Create new one if @do_create flag is set. */
1376 static void
1377 ldlm_send_and_maybe_create_set(struct ldlm_cb_set_arg *arg, int do_create)
1378 {
1379         ENTRY;
1380
1381         ptlrpc_set_wait(arg->set);
1382         if (arg->type == LDLM_BL_CALLBACK)
1383                 OBD_FAIL_TIMEOUT(OBD_FAIL_LDLM_GLIMPSE, 2);
1384         ptlrpc_set_destroy(arg->set);
1385
1386         if (do_create)
1387                 arg->set = ptlrpc_prep_set();
1388
1389         EXIT;
1390 }
1391
1392 static int
1393 ldlm_work_bl_ast_lock(cfs_list_t *tmp, struct ldlm_cb_set_arg *arg)
1394 {
1395         struct ldlm_lock_desc d;
1396         struct ldlm_lock *lock = cfs_list_entry(tmp, struct ldlm_lock,
1397                                                 l_bl_ast);
1398         ENTRY;
1399
1400         /* nobody should touch l_bl_ast */
1401         lock_res_and_lock(lock);
1402         cfs_list_del_init(&lock->l_bl_ast);
1403
1404         LASSERT(lock->l_flags & LDLM_FL_AST_SENT);
1405         LASSERT(lock->l_bl_ast_run == 0);
1406         LASSERT(lock->l_blocking_lock);
1407         lock->l_bl_ast_run++;
1408         unlock_res_and_lock(lock);
1409
1410         ldlm_lock2desc(lock->l_blocking_lock, &d);
1411
1412         lock->l_blocking_ast(lock, &d, (void *)arg,
1413                              LDLM_CB_BLOCKING);
1414         LDLM_LOCK_RELEASE(lock->l_blocking_lock);
1415         lock->l_blocking_lock = NULL;
1416         LDLM_LOCK_RELEASE(lock);
1417
1418         RETURN(1);
1419 }
1420
1421 static int
1422 ldlm_work_cp_ast_lock(cfs_list_t *tmp, struct ldlm_cb_set_arg *arg)
1423 {
1424         struct ldlm_lock *lock = cfs_list_entry(tmp, struct ldlm_lock, l_cp_ast);
1425         ldlm_completion_callback completion_callback;
1426         int rc = 0;
1427         ENTRY;
1428
1429         /* It's possible to receive a completion AST before we've set
1430          * the l_completion_ast pointer: either because the AST arrived
1431          * before the reply, or simply because there's a small race
1432          * window between receiving the reply and finishing the local
1433          * enqueue. (bug 842)
1434          *
1435          * This can't happen with the blocking_ast, however, because we
1436          * will never call the local blocking_ast until we drop our
1437          * reader/writer reference, which we won't do until we get the
1438          * reply and finish enqueueing. */
1439
1440         /* nobody should touch l_cp_ast */
1441         lock_res_and_lock(lock);
1442         cfs_list_del_init(&lock->l_cp_ast);
1443         LASSERT(lock->l_flags & LDLM_FL_CP_REQD);
1444         /* save l_completion_ast since it can be changed by
1445          * mds_intent_policy(), see bug 14225 */
1446         completion_callback = lock->l_completion_ast;
1447         lock->l_flags &= ~LDLM_FL_CP_REQD;
1448         unlock_res_and_lock(lock);
1449
1450         if (completion_callback != NULL) {
1451                 completion_callback(lock, 0, (void *)arg);
1452                 rc = 1;
1453         }
1454         LDLM_LOCK_RELEASE(lock);
1455
1456         RETURN(rc);
1457 }
1458
1459 static int
1460 ldlm_work_revoke_ast_lock(cfs_list_t *tmp, struct ldlm_cb_set_arg *arg)
1461 {
1462         struct ldlm_lock_desc desc;
1463         struct ldlm_lock *lock = cfs_list_entry(tmp, struct ldlm_lock,
1464                                                 l_rk_ast);
1465         ENTRY;
1466
1467         cfs_list_del_init(&lock->l_rk_ast);
1468
1469         /* the desc just pretend to exclusive */
1470         ldlm_lock2desc(lock, &desc);
1471         desc.l_req_mode = LCK_EX;
1472         desc.l_granted_mode = 0;
1473
1474         lock->l_blocking_ast(lock, &desc, (void*)arg, LDLM_CB_BLOCKING);
1475         LDLM_LOCK_RELEASE(lock);
1476
1477         RETURN(1);
1478 }
1479
1480 int ldlm_run_ast_work(cfs_list_t *rpc_list, ldlm_desc_ast_t ast_type)
1481 {
1482         struct ldlm_cb_set_arg arg;
1483         cfs_list_t *tmp, *pos;
1484         int (*work_ast_lock)(cfs_list_t *tmp, struct ldlm_cb_set_arg *arg);
1485         int ast_count;
1486         ENTRY;
1487
1488         if (cfs_list_empty(rpc_list))
1489                 RETURN(0);
1490
1491         arg.set = ptlrpc_prep_set();
1492         if (NULL == arg.set)
1493                 RETURN(-ERESTART);
1494         cfs_atomic_set(&arg.restart, 0);
1495         switch (ast_type) {
1496         case LDLM_WORK_BL_AST:
1497                 arg.type = LDLM_BL_CALLBACK;
1498                 work_ast_lock = ldlm_work_bl_ast_lock;
1499                 break;
1500         case LDLM_WORK_CP_AST:
1501                 arg.type = LDLM_CP_CALLBACK;
1502                 work_ast_lock = ldlm_work_cp_ast_lock;
1503                 break;
1504         case LDLM_WORK_REVOKE_AST:
1505                 arg.type = LDLM_BL_CALLBACK;
1506                 work_ast_lock = ldlm_work_revoke_ast_lock;
1507                 break;
1508         default:
1509                 LBUG();
1510         }
1511
1512         ast_count = 0;
1513         cfs_list_for_each_safe(tmp, pos, rpc_list) {
1514                 ast_count += work_ast_lock(tmp, &arg);
1515
1516                 /* Send the request set if it exceeds the PARALLEL_AST_LIMIT,
1517                  * and create a new set for requests that remained in
1518                  * @rpc_list */
1519                 if (unlikely(ast_count == PARALLEL_AST_LIMIT)) {
1520                         ldlm_send_and_maybe_create_set(&arg, 1);
1521                         ast_count = 0;
1522                 }
1523         }
1524
1525         if (ast_count > 0)
1526                 ldlm_send_and_maybe_create_set(&arg, 0);
1527         else
1528                 /* In case when number of ASTs is multiply of
1529                  * PARALLEL_AST_LIMIT or @rpc_list was initially empty,
1530                  * @arg.set must be destroyed here, otherwise we get
1531                  * write memory leaking. */
1532                 ptlrpc_set_destroy(arg.set);
1533
1534         RETURN(cfs_atomic_read(&arg.restart) ? -ERESTART : 0);
1535 }
1536
1537 static int reprocess_one_queue(struct ldlm_resource *res, void *closure)
1538 {
1539         ldlm_reprocess_all(res);
1540         return LDLM_ITER_CONTINUE;
1541 }
1542
1543 void ldlm_reprocess_all_ns(struct ldlm_namespace *ns)
1544 {
1545         cfs_list_t *tmp;
1546         int i, rc;
1547
1548         if (ns == NULL)
1549                 return;
1550
1551         ENTRY;
1552         cfs_spin_lock(&ns->ns_hash_lock);
1553         for (i = 0; i < RES_HASH_SIZE; i++) {
1554                 tmp = ns->ns_hash[i].next;
1555                 while (tmp != &(ns->ns_hash[i])) {
1556                         struct ldlm_resource *res =
1557                                 cfs_list_entry(tmp, struct ldlm_resource,
1558                                                lr_hash);
1559
1560                         ldlm_resource_getref(res);
1561                         cfs_spin_unlock(&ns->ns_hash_lock);
1562                         LDLM_RESOURCE_ADDREF(res);
1563
1564                         rc = reprocess_one_queue(res, NULL);
1565
1566                         LDLM_RESOURCE_DELREF(res);
1567                         cfs_spin_lock(&ns->ns_hash_lock);
1568                         tmp = tmp->next;
1569                         ldlm_resource_putref_locked(res);
1570
1571                         if (rc == LDLM_ITER_STOP)
1572                                 GOTO(out, rc);
1573                 }
1574         }
1575  out:
1576         cfs_spin_unlock(&ns->ns_hash_lock);
1577         EXIT;
1578 }
1579
1580 void ldlm_reprocess_all(struct ldlm_resource *res)
1581 {
1582         CFS_LIST_HEAD(rpc_list);
1583         int rc;
1584         ENTRY;
1585
1586         /* Local lock trees don't get reprocessed. */
1587         if (ns_is_client(ldlm_res_to_ns(res))) {
1588                 EXIT;
1589                 return;
1590         }
1591
1592  restart:
1593         lock_res(res);
1594         rc = ldlm_reprocess_queue(res, &res->lr_converting, &rpc_list);
1595         if (rc == LDLM_ITER_CONTINUE)
1596                 ldlm_reprocess_queue(res, &res->lr_waiting, &rpc_list);
1597         unlock_res(res);
1598
1599         rc = ldlm_run_ast_work(&rpc_list, LDLM_WORK_CP_AST);
1600         if (rc == -ERESTART) {
1601                 LASSERT(cfs_list_empty(&rpc_list));
1602                 goto restart;
1603         }
1604         EXIT;
1605 }
1606
1607 void ldlm_cancel_callback(struct ldlm_lock *lock)
1608 {
1609         check_res_locked(lock->l_resource);
1610         if (!(lock->l_flags & LDLM_FL_CANCEL)) {
1611                 lock->l_flags |= LDLM_FL_CANCEL;
1612                 if (lock->l_blocking_ast) {
1613                         // l_check_no_ns_lock(ns);
1614                         unlock_res_and_lock(lock);
1615                         lock->l_blocking_ast(lock, NULL, lock->l_ast_data,
1616                                              LDLM_CB_CANCELING);
1617                         lock_res_and_lock(lock);
1618                 } else {
1619                         LDLM_DEBUG(lock, "no blocking ast");
1620                 }
1621         }
1622         lock->l_flags |= LDLM_FL_BL_DONE;
1623 }
1624
1625 void ldlm_unlink_lock_skiplist(struct ldlm_lock *req)
1626 {
1627         if (req->l_resource->lr_type != LDLM_PLAIN &&
1628             req->l_resource->lr_type != LDLM_IBITS)
1629                 return;
1630
1631         cfs_list_del_init(&req->l_sl_policy);
1632         cfs_list_del_init(&req->l_sl_mode);
1633 }
1634
1635 void ldlm_lock_cancel(struct ldlm_lock *lock)
1636 {
1637         struct ldlm_resource *res;
1638         struct ldlm_namespace *ns;
1639         ENTRY;
1640
1641         lock_res_and_lock(lock);
1642
1643         res = lock->l_resource;
1644         ns  = ldlm_res_to_ns(res);
1645
1646         /* Please do not, no matter how tempting, remove this LBUG without
1647          * talking to me first. -phik */
1648         if (lock->l_readers || lock->l_writers) {
1649                 LDLM_ERROR(lock, "lock still has references");
1650                 LBUG();
1651         }
1652
1653         ldlm_del_waiting_lock(lock);
1654
1655         /* Releases cancel callback. */
1656         ldlm_cancel_callback(lock);
1657
1658         /* Yes, second time, just in case it was added again while we were
1659            running with no res lock in ldlm_cancel_callback */
1660         ldlm_del_waiting_lock(lock);
1661         ldlm_resource_unlink_lock(lock);
1662         ldlm_lock_destroy_nolock(lock);
1663
1664         if (lock->l_granted_mode == lock->l_req_mode)
1665                 ldlm_pool_del(&ns->ns_pool, lock);
1666
1667         /* Make sure we will not be called again for same lock what is possible
1668          * if not to zero out lock->l_granted_mode */
1669         lock->l_granted_mode = LCK_MINMODE;
1670         unlock_res_and_lock(lock);
1671
1672         EXIT;
1673 }
1674
1675 int ldlm_lock_set_data(struct lustre_handle *lockh, void *data)
1676 {
1677         struct ldlm_lock *lock = ldlm_handle2lock(lockh);
1678         ENTRY;
1679
1680         if (lock == NULL)
1681                 RETURN(-EINVAL);
1682
1683         lock->l_ast_data = data;
1684         LDLM_LOCK_PUT(lock);
1685         RETURN(0);
1686 }
1687
1688 int ldlm_cancel_locks_for_export_cb(cfs_hash_t *hs, cfs_hash_bd_t *bd,
1689                                     cfs_hlist_node_t *hnode, void *data)
1690
1691 {
1692         struct obd_export    *exp  = data;
1693         struct ldlm_lock     *lock = cfs_hash_object(hs, hnode);
1694         struct ldlm_resource *res;
1695
1696         res = ldlm_resource_getref(lock->l_resource);
1697         LDLM_LOCK_GET(lock);
1698
1699         LDLM_DEBUG(lock, "export %p", exp);
1700         ldlm_res_lvbo_update(res, NULL, 1);
1701         ldlm_lock_cancel(lock);
1702         ldlm_reprocess_all(res);
1703         ldlm_resource_putref(res);
1704         LDLM_LOCK_RELEASE(lock);
1705         return 0;
1706 }
1707
1708 void ldlm_cancel_locks_for_export(struct obd_export *exp)
1709 {
1710         cfs_hash_for_each_empty(exp->exp_lock_hash,
1711                                 ldlm_cancel_locks_for_export_cb, exp);
1712 }
1713
1714 /**
1715  * Downgrade an exclusive lock.
1716  *
1717  * A fast variant of ldlm_lock_convert for convertion of exclusive
1718  * locks. The convertion is always successful.
1719  *
1720  * \param lock A lock to convert
1721  * \param new_mode new lock mode
1722  */
1723 void ldlm_lock_downgrade(struct ldlm_lock *lock, int new_mode)
1724 {
1725         struct ldlm_namespace *ns;
1726         ENTRY;
1727
1728         LASSERT(lock->l_granted_mode & (LCK_PW | LCK_EX));
1729         LASSERT(new_mode == LCK_COS);
1730
1731         lock_res_and_lock(lock);
1732         ldlm_resource_unlink_lock(lock);
1733         /*
1734          * Remove the lock from pool as it will be added again in
1735          * ldlm_grant_lock() called below.
1736          */
1737         ns = ldlm_lock_to_ns(lock);
1738         ldlm_pool_del(&ns->ns_pool, lock);
1739
1740         lock->l_req_mode = new_mode;
1741         ldlm_grant_lock(lock, NULL);
1742         unlock_res_and_lock(lock);
1743         ldlm_reprocess_all(lock->l_resource);
1744
1745         EXIT;
1746 }
1747
1748 struct ldlm_resource *ldlm_lock_convert(struct ldlm_lock *lock, int new_mode,
1749                                         __u32 *flags)
1750 {
1751         CFS_LIST_HEAD(rpc_list);
1752         struct ldlm_resource *res;
1753         struct ldlm_namespace *ns;
1754         int granted = 0;
1755         int old_mode, rc;
1756         struct sl_insert_point prev;
1757         ldlm_error_t err;
1758         struct ldlm_interval *node;
1759         ENTRY;
1760
1761         if (new_mode == lock->l_granted_mode) { // No changes? Just return.
1762                 *flags |= LDLM_FL_BLOCK_GRANTED;
1763                 RETURN(lock->l_resource);
1764         }
1765
1766         /* I can't check the type of lock here because the bitlock of lock
1767          * is not held here, so do the allocation blindly. -jay */
1768         OBD_SLAB_ALLOC_PTR_GFP(node, ldlm_interval_slab, CFS_ALLOC_IO);
1769         if (node == NULL)  /* Actually, this causes EDEADLOCK to be returned */
1770                 RETURN(NULL);
1771
1772         LASSERTF((new_mode == LCK_PW && lock->l_granted_mode == LCK_PR),
1773                  "new_mode %u, granted %u\n", new_mode, lock->l_granted_mode);
1774
1775         lock_res_and_lock(lock);
1776
1777         res = lock->l_resource;
1778         ns  = ldlm_res_to_ns(res);
1779
1780         old_mode = lock->l_req_mode;
1781         lock->l_req_mode = new_mode;
1782         if (res->lr_type == LDLM_PLAIN || res->lr_type == LDLM_IBITS) {
1783                 /* remember the lock position where the lock might be
1784                  * added back to the granted list later and also
1785                  * remember the join mode for skiplist fixing. */
1786                 prev.res_link = lock->l_res_link.prev;
1787                 prev.mode_link = lock->l_sl_mode.prev;
1788                 prev.policy_link = lock->l_sl_policy.prev;
1789                 ldlm_resource_unlink_lock(lock);
1790         } else {
1791                 ldlm_resource_unlink_lock(lock);
1792                 if (res->lr_type == LDLM_EXTENT) {
1793                         /* FIXME: ugly code, I have to attach the lock to a
1794                          * interval node again since perhaps it will be granted
1795                          * soon */
1796                         CFS_INIT_LIST_HEAD(&node->li_group);
1797                         ldlm_interval_attach(node, lock);
1798                         node = NULL;
1799                 }
1800         }
1801
1802         /*
1803          * Remove old lock from the pool before adding the lock with new
1804          * mode below in ->policy()
1805          */
1806         ldlm_pool_del(&ns->ns_pool, lock);
1807
1808         /* If this is a local resource, put it on the appropriate list. */
1809         if (ns_is_client(ldlm_res_to_ns(res))) {
1810                 if (*flags & (LDLM_FL_BLOCK_CONV | LDLM_FL_BLOCK_GRANTED)) {
1811                         ldlm_resource_add_lock(res, &res->lr_converting, lock);
1812                 } else {
1813                         /* This should never happen, because of the way the
1814                          * server handles conversions. */
1815                         LDLM_ERROR(lock, "Erroneous flags %d on local lock\n",
1816                                    *flags);
1817                         LBUG();
1818
1819                         ldlm_grant_lock(lock, &rpc_list);
1820                         granted = 1;
1821                         /* FIXME: completion handling not with ns_lock held ! */
1822                         if (lock->l_completion_ast)
1823                                 lock->l_completion_ast(lock, 0, NULL);
1824                 }
1825         } else {
1826                 int pflags = 0;
1827                 ldlm_processing_policy policy;
1828                 policy = ldlm_processing_policy_table[res->lr_type];
1829                 rc = policy(lock, &pflags, 0, &err, &rpc_list);
1830                 if (rc == LDLM_ITER_STOP) {
1831                         lock->l_req_mode = old_mode;
1832                         if (res->lr_type == LDLM_EXTENT)
1833                                 ldlm_extent_add_lock(res, lock);
1834                         else
1835                                 ldlm_granted_list_add_lock(lock, &prev);
1836
1837                         res = NULL;
1838                 } else {
1839                         *flags |= LDLM_FL_BLOCK_GRANTED;
1840                         granted = 1;
1841                 }
1842         }
1843         unlock_res_and_lock(lock);
1844
1845         if (granted)
1846                 ldlm_run_ast_work(&rpc_list, LDLM_WORK_CP_AST);
1847         if (node)
1848                 OBD_SLAB_FREE(node, ldlm_interval_slab, sizeof(*node));
1849         RETURN(res);
1850 }
1851
1852 void ldlm_lock_dump(int level, struct ldlm_lock *lock, int pos)
1853 {
1854         struct obd_device *obd = NULL;
1855
1856         if (!((libcfs_debug | D_ERROR) & level))
1857                 return;
1858
1859         if (!lock) {
1860                 CDEBUG(level, "  NULL LDLM lock\n");
1861                 return;
1862         }
1863
1864         CDEBUG(level," -- Lock dump: %p/"LPX64" (rc: %d) (pos: %d) (pid: %d)\n",
1865                lock, lock->l_handle.h_cookie, cfs_atomic_read(&lock->l_refc),
1866                pos, lock->l_pid);
1867         if (lock->l_conn_export != NULL)
1868                 obd = lock->l_conn_export->exp_obd;
1869         if (lock->l_export && lock->l_export->exp_connection) {
1870                 CDEBUG(level, "  Node: NID %s (rhandle: "LPX64")\n",
1871                      libcfs_nid2str(lock->l_export->exp_connection->c_peer.nid),
1872                      lock->l_remote_handle.cookie);
1873         } else if (obd == NULL) {
1874                 CDEBUG(level, "  Node: local\n");
1875         } else {
1876                 struct obd_import *imp = obd->u.cli.cl_import;
1877                 CDEBUG(level, "  Node: NID %s (rhandle: "LPX64")\n",
1878                        libcfs_nid2str(imp->imp_connection->c_peer.nid),
1879                        lock->l_remote_handle.cookie);
1880         }
1881         CDEBUG(level, "  Resource: %p ("LPU64"/"LPU64"/"LPU64")\n",
1882                   lock->l_resource,
1883                   lock->l_resource->lr_name.name[0],
1884                   lock->l_resource->lr_name.name[1],
1885                   lock->l_resource->lr_name.name[2]);
1886         CDEBUG(level, "  Req mode: %s, grant mode: %s, rc: %u, read: %d, "
1887                "write: %d flags: "LPX64"\n", ldlm_lockname[lock->l_req_mode],
1888                ldlm_lockname[lock->l_granted_mode],
1889                cfs_atomic_read(&lock->l_refc), lock->l_readers, lock->l_writers,
1890                lock->l_flags);
1891         if (lock->l_resource->lr_type == LDLM_EXTENT)
1892                 CDEBUG(level, "  Extent: "LPU64" -> "LPU64
1893                        " (req "LPU64"-"LPU64")\n",
1894                        lock->l_policy_data.l_extent.start,
1895                        lock->l_policy_data.l_extent.end,
1896                        lock->l_req_extent.start, lock->l_req_extent.end);
1897         else if (lock->l_resource->lr_type == LDLM_FLOCK)
1898                 CDEBUG(level, "  Pid: %d Extent: "LPU64" -> "LPU64"\n",
1899                        lock->l_policy_data.l_flock.pid,
1900                        lock->l_policy_data.l_flock.start,
1901                        lock->l_policy_data.l_flock.end);
1902        else if (lock->l_resource->lr_type == LDLM_IBITS)
1903                 CDEBUG(level, "  Bits: "LPX64"\n",
1904                        lock->l_policy_data.l_inodebits.bits);
1905 }
1906
1907 void ldlm_lock_dump_handle(int level, struct lustre_handle *lockh)
1908 {
1909         struct ldlm_lock *lock;
1910
1911         if (!((libcfs_debug | D_ERROR) & level))
1912                 return;
1913
1914         lock = ldlm_handle2lock(lockh);
1915         if (lock == NULL)
1916                 return;
1917
1918         ldlm_lock_dump(D_OTHER, lock, 0);
1919
1920         LDLM_LOCK_PUT(lock);
1921 }
1922
1923 void _ldlm_lock_debug(struct ldlm_lock *lock, __u32 level,
1924                       struct libcfs_debug_msg_data *data, const char *fmt,
1925                       ...)
1926 {
1927         va_list args;
1928         cfs_debug_limit_state_t *cdls = data->msg_cdls;
1929
1930         va_start(args, fmt);
1931
1932         if (lock->l_resource == NULL) {
1933                 libcfs_debug_vmsg2(cdls, data->msg_subsys, level,data->msg_file,
1934                                    data->msg_fn, data->msg_line, fmt, args,
1935                        " ns: \?\? lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
1936                        "res: \?\? rrc=\?\? type: \?\?\? flags: "LPX64" remote: "
1937                        LPX64" expref: %d pid: %u timeout: %lu\n", lock,
1938                        lock->l_handle.h_cookie, cfs_atomic_read(&lock->l_refc),
1939                        lock->l_readers, lock->l_writers,
1940                        ldlm_lockname[lock->l_granted_mode],
1941                        ldlm_lockname[lock->l_req_mode],
1942                        lock->l_flags, lock->l_remote_handle.cookie,
1943                        lock->l_export ?
1944                        cfs_atomic_read(&lock->l_export->exp_refcount) : -99,
1945                        lock->l_pid, lock->l_callback_timeout);
1946                 va_end(args);
1947                 return;
1948         }
1949
1950         switch (lock->l_resource->lr_type) {
1951         case LDLM_EXTENT:
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" rrc: %d type: %s ["LPU64"->"LPU64
1956                        "] (req "LPU64"->"LPU64") flags: "LPX64" remote: "LPX64
1957                        " expref: %d pid: %u timeout %lu\n",
1958                        ldlm_lock_to_ns_name(lock), lock,
1959                        lock->l_handle.h_cookie, cfs_atomic_read(&lock->l_refc),
1960                        lock->l_readers, lock->l_writers,
1961                        ldlm_lockname[lock->l_granted_mode],
1962                        ldlm_lockname[lock->l_req_mode],
1963                        lock->l_resource->lr_name.name[0],
1964                        lock->l_resource->lr_name.name[1],
1965                        cfs_atomic_read(&lock->l_resource->lr_refcount),
1966                        ldlm_typename[lock->l_resource->lr_type],
1967                        lock->l_policy_data.l_extent.start,
1968                        lock->l_policy_data.l_extent.end,
1969                        lock->l_req_extent.start, lock->l_req_extent.end,
1970                        lock->l_flags, lock->l_remote_handle.cookie,
1971                        lock->l_export ?
1972                        cfs_atomic_read(&lock->l_export->exp_refcount) : -99,
1973                        lock->l_pid, lock->l_callback_timeout);
1974                 break;
1975
1976         case LDLM_FLOCK:
1977                 libcfs_debug_vmsg2(cdls, data->msg_subsys, level,data->msg_file,
1978                                    data->msg_fn, data->msg_line, fmt, args,
1979                        " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
1980                        "res: "LPU64"/"LPU64" rrc: %d type: %s pid: %d "
1981                        "["LPU64"->"LPU64"] flags: "LPX64" remote: "LPX64
1982                        " expref: %d pid: %u timeout: %lu\n",
1983                        ldlm_lock_to_ns_name(lock), lock,
1984                        lock->l_handle.h_cookie, cfs_atomic_read(&lock->l_refc),
1985                        lock->l_readers, lock->l_writers,
1986                        ldlm_lockname[lock->l_granted_mode],
1987                        ldlm_lockname[lock->l_req_mode],
1988                        lock->l_resource->lr_name.name[0],
1989                        lock->l_resource->lr_name.name[1],
1990                        cfs_atomic_read(&lock->l_resource->lr_refcount),
1991                        ldlm_typename[lock->l_resource->lr_type],
1992                        lock->l_policy_data.l_flock.pid,
1993                        lock->l_policy_data.l_flock.start,
1994                        lock->l_policy_data.l_flock.end,
1995                        lock->l_flags, lock->l_remote_handle.cookie,
1996                        lock->l_export ?
1997                        cfs_atomic_read(&lock->l_export->exp_refcount) : -99,
1998                        lock->l_pid, lock->l_callback_timeout);
1999                 break;
2000
2001         case LDLM_IBITS:
2002                 libcfs_debug_vmsg2(cdls, data->msg_subsys, level,data->msg_file,
2003                                    data->msg_fn, data->msg_line, fmt, args,
2004                        " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
2005                        "res: "LPU64"/"LPU64" bits "LPX64" rrc: %d type: %s "
2006                        "flags: "LPX64" remote: "LPX64" expref: %d "
2007                        "pid: %u timeout: %lu\n",
2008                        ldlm_lock_to_ns_name(lock),
2009                        lock, lock->l_handle.h_cookie,
2010                        cfs_atomic_read (&lock->l_refc),
2011                        lock->l_readers, lock->l_writers,
2012                        ldlm_lockname[lock->l_granted_mode],
2013                        ldlm_lockname[lock->l_req_mode],
2014                        lock->l_resource->lr_name.name[0],
2015                        lock->l_resource->lr_name.name[1],
2016                        lock->l_policy_data.l_inodebits.bits,
2017                        cfs_atomic_read(&lock->l_resource->lr_refcount),
2018                        ldlm_typename[lock->l_resource->lr_type],
2019                        lock->l_flags, lock->l_remote_handle.cookie,
2020                        lock->l_export ?
2021                        cfs_atomic_read(&lock->l_export->exp_refcount) : -99,
2022                        lock->l_pid, lock->l_callback_timeout);
2023                 break;
2024
2025         default:
2026                 libcfs_debug_vmsg2(cdls, data->msg_subsys, level,data->msg_file,
2027                                    data->msg_fn, data->msg_line, fmt, args,
2028                        " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
2029                        "res: "LPU64"/"LPU64" rrc: %d type: %s flags: "LPX64" "
2030                        "remote: "LPX64" expref: %d pid: %u timeout %lu\n",
2031                        ldlm_lock_to_ns_name(lock),
2032                        lock, lock->l_handle.h_cookie,
2033                        cfs_atomic_read (&lock->l_refc),
2034                        lock->l_readers, lock->l_writers,
2035                        ldlm_lockname[lock->l_granted_mode],
2036                        ldlm_lockname[lock->l_req_mode],
2037                        lock->l_resource->lr_name.name[0],
2038                        lock->l_resource->lr_name.name[1],
2039                        cfs_atomic_read(&lock->l_resource->lr_refcount),
2040                        ldlm_typename[lock->l_resource->lr_type],
2041                        lock->l_flags, lock->l_remote_handle.cookie,
2042                        lock->l_export ?
2043                        cfs_atomic_read(&lock->l_export->exp_refcount) : -99,
2044                        lock->l_pid, lock->l_callback_timeout);
2045                 break;
2046         }
2047         va_end(args);
2048 }
2049 EXPORT_SYMBOL(_ldlm_lock_debug);