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         cfs_spin_lock(&ns->ns_unused_lock);
 207         rc = ldlm_lock_remove_from_lru_nolock(lock);
 208         cfs_spin_unlock(&ns->ns_unused_lock);
 209         EXIT;
 210         return rc;
 211 }
 212
 213 void ldlm_lock_add_to_lru_nolock(struct ldlm_lock *lock)
 214 {
 215         struct ldlm_namespace *ns = ldlm_lock_to_ns(lock);
 216
 217         lock->l_last_used = cfs_time_current();
 218         LASSERT(cfs_list_empty(&lock->l_lru));
 219         LASSERT(lock->l_resource->lr_type != LDLM_FLOCK);
 220         cfs_list_add_tail(&lock->l_lru, &ns->ns_unused_list);
 221         LASSERT(ns->ns_nr_unused >= 0);
 222         ns->ns_nr_unused++;
 223 }
 224
 225 void ldlm_lock_add_to_lru(struct ldlm_lock *lock)
 226 {
 227         struct ldlm_namespace *ns = ldlm_lock_to_ns(lock);
 228
 229         ENTRY;
 230         cfs_spin_lock(&ns->ns_unused_lock);
 231         ldlm_lock_add_to_lru_nolock(lock);
 232         cfs_spin_unlock(&ns->ns_unused_lock);
 233         EXIT;
 234 }
 235
 236 void ldlm_lock_touch_in_lru(struct ldlm_lock *lock)
 237 {
 238         struct ldlm_namespace *ns = ldlm_lock_to_ns(lock);
 239
 240         ENTRY;
 241         cfs_spin_lock(&ns->ns_unused_lock);
 242         if (!cfs_list_empty(&lock->l_lru)) {
 243                 ldlm_lock_remove_from_lru_nolock(lock);
 244                 ldlm_lock_add_to_lru_nolock(lock);
 245         }
 246         cfs_spin_unlock(&ns->ns_unused_lock);
 247         EXIT;
 248 }
 249
 250 /* This used to have a 'strict' flag, which recovery would use to mark an
 251  * in-use lock as needing-to-die.  Lest I am ever tempted to put it back, I
 252  * shall explain why it's gone: with the new hash table scheme, once you call
 253  * ldlm_lock_destroy, you can never drop your final references on this lock.
 254  * Because it's not in the hash table anymore.  -phil */
 255 int ldlm_lock_destroy_internal(struct ldlm_lock *lock)
 256 {
 257         ENTRY;
 258
 259         if (lock->l_readers || lock->l_writers) {
 260                 LDLM_ERROR(lock, "lock still has references");
 261                 ldlm_lock_dump(D_ERROR, lock, 0);
 262                 LBUG();
 263         }
 264
 265         if (!cfs_list_empty(&lock->l_res_link)) {
 266                 LDLM_ERROR(lock, "lock still on resource");
 267                 ldlm_lock_dump(D_ERROR, lock, 0);
 268                 LBUG();
 269         }
 270
 271         if (lock->l_destroyed) {
 272                 LASSERT(cfs_list_empty(&lock->l_lru));
 273                 EXIT;
 274                 return 0;
 275         }
 276         lock->l_destroyed = 1;
 277
 278         if (lock->l_export && lock->l_export->exp_lock_hash &&
 279             !cfs_hlist_unhashed(&lock->l_exp_hash))
 280                 cfs_hash_del(lock->l_export->exp_lock_hash,
 281                              &lock->l_remote_handle, &lock->l_exp_hash);
 282
 283         ldlm_lock_remove_from_lru(lock);
 284         class_handle_unhash(&lock->l_handle);
 285
 286 #if 0
 287         /* Wake anyone waiting for this lock */
 288         /* FIXME: I should probably add yet another flag, instead of using
 289          * l_export to only call this on clients */
 290         if (lock->l_export)
 291                 class_export_put(lock->l_export);
 292         lock->l_export = NULL;
 293         if (lock->l_export && lock->l_completion_ast)
 294                 lock->l_completion_ast(lock, 0);
 295 #endif
 296         EXIT;
 297         return 1;
 298 }
 299
 300 void ldlm_lock_destroy(struct ldlm_lock *lock)
 301 {
 302         int first;
 303         ENTRY;
 304         lock_res_and_lock(lock);
 305         first = ldlm_lock_destroy_internal(lock);
 306         unlock_res_and_lock(lock);
 307
 308         /* drop reference from hashtable only for first destroy */
 309         if (first) {
 310                 lu_ref_del(&lock->l_reference, "hash", lock);
 311                 LDLM_LOCK_RELEASE(lock);
 312         }
 313         EXIT;
 314 }
 315
 316 void ldlm_lock_destroy_nolock(struct ldlm_lock *lock)
 317 {
 318         int first;
 319         ENTRY;
 320         first = ldlm_lock_destroy_internal(lock);
 321         /* drop reference from hashtable only for first destroy */
 322         if (first) {
 323                 lu_ref_del(&lock->l_reference, "hash", lock);
 324                 LDLM_LOCK_RELEASE(lock);
 325         }
 326         EXIT;
 327 }
 328
 329 /* this is called by portals_handle2object with the handle lock taken */
 330 static void lock_handle_addref(void *lock)
 331 {
 332         LDLM_LOCK_GET((struct ldlm_lock *)lock);
 333 }
 334
 335 /*
 336  * usage: pass in a resource on which you have done ldlm_resource_get
 337  *        pass in a parent lock on which you have done a ldlm_lock_get
 338  *        after return, ldlm_*_put the resource and parent
 339  * returns: lock with refcount 2 - one for current caller and one for remote
 340  */
 341 static struct ldlm_lock *ldlm_lock_new(struct ldlm_resource *resource)
 342 {
 343         struct ldlm_lock *lock;
 344         ENTRY;
 345
 346         if (resource == NULL)
 347                 LBUG();
 348
 349         OBD_SLAB_ALLOC_PTR_GFP(lock, ldlm_lock_slab, CFS_ALLOC_IO);
 350         if (lock == NULL)
 351                 RETURN(NULL);
 352
 353         cfs_spin_lock_init(&lock->l_lock);
 354         lock->l_resource = ldlm_resource_getref(resource);
 355         lu_ref_add(&resource->lr_reference, "lock", lock);
 356
 357         cfs_atomic_set(&lock->l_refc, 2);
 358         CFS_INIT_LIST_HEAD(&lock->l_res_link);
 359         CFS_INIT_LIST_HEAD(&lock->l_lru);
 360         CFS_INIT_LIST_HEAD(&lock->l_pending_chain);
 361         CFS_INIT_LIST_HEAD(&lock->l_bl_ast);
 362         CFS_INIT_LIST_HEAD(&lock->l_cp_ast);
 363         CFS_INIT_LIST_HEAD(&lock->l_rk_ast);
 364         cfs_waitq_init(&lock->l_waitq);
 365         lock->l_blocking_lock = NULL;
 366         CFS_INIT_LIST_HEAD(&lock->l_sl_mode);
 367         CFS_INIT_LIST_HEAD(&lock->l_sl_policy);
 368         CFS_INIT_HLIST_NODE(&lock->l_exp_hash);
 369
 370         cfs_atomic_inc(&ldlm_res_to_ns(resource)->ns_locks);
 371         CFS_INIT_LIST_HEAD(&lock->l_handle.h_link);
 372         class_handle_hash(&lock->l_handle, lock_handle_addref);
 373
 374         lu_ref_init(&lock->l_reference);
 375         lu_ref_add(&lock->l_reference, "hash", lock);
 376         lock->l_callback_timeout = 0;
 377
 378 #if LUSTRE_TRACKS_LOCK_EXP_REFS
 379         CFS_INIT_LIST_HEAD(&lock->l_exp_refs_link);
 380         lock->l_exp_refs_nr = 0;
 381         lock->l_exp_refs_target = NULL;
 382 #endif
 383
 384         RETURN(lock);
 385 }
 386
 387 int ldlm_lock_change_resource(struct ldlm_namespace *ns, struct ldlm_lock *lock,
 388                               const struct ldlm_res_id *new_resid)
 389 {
 390         struct ldlm_resource *oldres = lock->l_resource;
 391         struct ldlm_resource *newres;
 392         int type;
 393         ENTRY;
 394
 395         LASSERT(ns_is_client(ns));
 396
 397         lock_res_and_lock(lock);
 398         if (memcmp(new_resid, &lock->l_resource->lr_name,
 399                    sizeof(lock->l_resource->lr_name)) == 0) {
 400                 /* Nothing to do */
 401                 unlock_res_and_lock(lock);
 402                 RETURN(0);
 403         }
 404
 405         LASSERT(new_resid->name[0] != 0);
 406
 407         /* This function assumes that the lock isn't on any lists */
 408         LASSERT(cfs_list_empty(&lock->l_res_link));
 409
 410         type = oldres->lr_type;
 411         unlock_res_and_lock(lock);
 412
 413         newres = ldlm_resource_get(ns, NULL, new_resid, type, 1);
 414         lu_ref_add(&newres->lr_reference, "lock", lock);
 415         if (newres == NULL)
 416                 RETURN(-ENOMEM);
 417         /*
 418          * To flip the lock from the old to the new resource, lock, oldres and
 419          * newres have to be locked. Resource spin-locks are nested within
 420          * lock->l_lock, and are taken in the memory address order to avoid
 421          * dead-locks.
 422          */
 423         cfs_spin_lock(&lock->l_lock);
 424         oldres = lock->l_resource;
 425         if (oldres < newres) {
 426                 lock_res(oldres);
 427                 lock_res_nested(newres, LRT_NEW);
 428         } else {
 429                 lock_res(newres);
 430                 lock_res_nested(oldres, LRT_NEW);
 431         }
 432         LASSERT(memcmp(new_resid, &oldres->lr_name,
 433                        sizeof oldres->lr_name) != 0);
 434         lock->l_resource = newres;
 435         unlock_res(oldres);
 436         unlock_res_and_lock(lock);
 437
 438         /* ...and the flowers are still standing! */
 439         lu_ref_del(&oldres->lr_reference, "lock", lock);
 440         ldlm_resource_putref(oldres);
 441
 442         RETURN(0);
 443 }
 444
 445 /*
 446  *  HANDLES
 447  */
 448
 449 void ldlm_lock2handle(const struct ldlm_lock *lock, struct lustre_handle *lockh)
 450 {
 451         lockh->cookie = lock->l_handle.h_cookie;
 452 }
 453
 454 /* if flags: atomically get the lock and set the flags.
 455  *           Return NULL if flag already set
 456  */
 457
 458 struct ldlm_lock *__ldlm_handle2lock(const struct lustre_handle *handle,
 459                                      int flags)
 460 {
 461         struct ldlm_namespace *ns;
 462         struct ldlm_lock *lock, *retval = NULL;
 463         ENTRY;
 464
 465         LASSERT(handle);
 466
 467         lock = class_handle2object(handle->cookie);
 468         if (lock == NULL)
 469                 RETURN(NULL);
 470
 471         LASSERT(lock->l_resource != NULL);
 472         ns = ldlm_lock_to_ns(lock);
 473         LASSERT(ns != NULL);
 474
 475         lu_ref_add_atomic(&lock->l_reference, "handle", cfs_current());
 476         lock_res_and_lock(lock);
 477
 478         /* It's unlikely but possible that someone marked the lock as
 479          * destroyed after we did handle2object on it */
 480         if (lock->l_destroyed) {
 481                 unlock_res_and_lock(lock);
 482                 CDEBUG(D_INFO, "lock already destroyed: lock %p\n", lock);
 483                 LDLM_LOCK_PUT(lock);
 484                 GOTO(out, retval);
 485         }
 486
 487         if (flags && (lock->l_flags & flags)) {
 488                 unlock_res_and_lock(lock);
 489                 LDLM_LOCK_PUT(lock);
 490                 GOTO(out, retval);
 491         }
 492
 493         if (flags)
 494                 lock->l_flags |= flags;
 495
 496         unlock_res_and_lock(lock);
 497         retval = lock;
 498         EXIT;
 499  out:
 500         return retval;
 501 }
 502
 503 void ldlm_lock2desc(struct ldlm_lock *lock, struct ldlm_lock_desc *desc)
 504 {
 505         struct obd_export *exp = lock->l_export?:lock->l_conn_export;
 506         /* INODEBITS_INTEROP: If the other side does not support
 507          * inodebits, reply with a plain lock descriptor.
 508          */
 509         if ((lock->l_resource->lr_type == LDLM_IBITS) &&
 510             (exp && !(exp->exp_connect_flags & OBD_CONNECT_IBITS))) {
 511                 /* Make sure all the right bits are set in this lock we
 512                    are going to pass to client */
 513                 LASSERTF(lock->l_policy_data.l_inodebits.bits ==
 514                          (MDS_INODELOCK_LOOKUP|MDS_INODELOCK_UPDATE),
 515                          "Inappropriate inode lock bits during "
 516                          "conversion " LPU64 "\n",
 517                          lock->l_policy_data.l_inodebits.bits);
 518
 519                 ldlm_res2desc(lock->l_resource, &desc->l_resource);
 520                 desc->l_resource.lr_type = LDLM_PLAIN;
 521
 522                 /* Convert "new" lock mode to something old client can
 523                    understand */
 524                 if ((lock->l_req_mode == LCK_CR) ||
 525                     (lock->l_req_mode == LCK_CW))
 526                         desc->l_req_mode = LCK_PR;
 527                 else
 528                         desc->l_req_mode = lock->l_req_mode;
 529                 if ((lock->l_granted_mode == LCK_CR) ||
 530                     (lock->l_granted_mode == LCK_CW)) {
 531                         desc->l_granted_mode = LCK_PR;
 532                 } else {
 533                         /* We never grant PW/EX locks to clients */
 534                         LASSERT((lock->l_granted_mode != LCK_PW) &&
 535                                 (lock->l_granted_mode != LCK_EX));
 536                         desc->l_granted_mode = lock->l_granted_mode;
 537                 }
 538
 539                 /* We do not copy policy here, because there is no
 540                    policy for plain locks */
 541         } else {
 542                 ldlm_res2desc(lock->l_resource, &desc->l_resource);
 543                 desc->l_req_mode = lock->l_req_mode;
 544                 desc->l_granted_mode = lock->l_granted_mode;
 545                 desc->l_policy_data = lock->l_policy_data;
 546         }
 547 }
 548
 549 void ldlm_add_bl_work_item(struct ldlm_lock *lock, struct ldlm_lock *new,
 550                            cfs_list_t *work_list)
 551 {
 552         if ((lock->l_flags & LDLM_FL_AST_SENT) == 0) {
 553                 LDLM_DEBUG(lock, "lock incompatible; sending blocking AST.");
 554                 lock->l_flags |= LDLM_FL_AST_SENT;
 555                 /* If the enqueuing client said so, tell the AST recipient to
 556                  * discard dirty data, rather than writing back. */
 557                 if (new->l_flags & LDLM_AST_DISCARD_DATA)
 558                         lock->l_flags |= LDLM_FL_DISCARD_DATA;
 559                 LASSERT(cfs_list_empty(&lock->l_bl_ast));
 560                 cfs_list_add(&lock->l_bl_ast, work_list);
 561                 LDLM_LOCK_GET(lock);
 562                 LASSERT(lock->l_blocking_lock == NULL);
 563                 lock->l_blocking_lock = LDLM_LOCK_GET(new);
 564         }
 565 }
 566
 567 void ldlm_add_cp_work_item(struct ldlm_lock *lock, cfs_list_t *work_list)
 568 {
 569         if ((lock->l_flags & LDLM_FL_CP_REQD) == 0) {
 570                 lock->l_flags |= LDLM_FL_CP_REQD;
 571                 LDLM_DEBUG(lock, "lock granted; sending completion AST.");
 572                 LASSERT(cfs_list_empty(&lock->l_cp_ast));
 573                 cfs_list_add(&lock->l_cp_ast, work_list);
 574                 LDLM_LOCK_GET(lock);
 575         }
 576 }
 577
 578 /* must be called with lr_lock held */
 579 void ldlm_add_ast_work_item(struct ldlm_lock *lock, struct ldlm_lock *new,
 580                             cfs_list_t *work_list)
 581 {
 582         ENTRY;
 583         check_res_locked(lock->l_resource);
 584         if (new)
 585                 ldlm_add_bl_work_item(lock, new, work_list);
 586         else
 587                 ldlm_add_cp_work_item(lock, work_list);
 588         EXIT;
 589 }
 590
 591 void ldlm_lock_addref(struct lustre_handle *lockh, __u32 mode)
 592 {
 593         struct ldlm_lock *lock;
 594
 595         lock = ldlm_handle2lock(lockh);
 596         LASSERT(lock != NULL);
 597         ldlm_lock_addref_internal(lock, mode);
 598         LDLM_LOCK_PUT(lock);
 599 }
 600
 601 void ldlm_lock_addref_internal_nolock(struct ldlm_lock *lock, __u32 mode)
 602 {
 603         ldlm_lock_remove_from_lru(lock);
 604         if (mode & (LCK_NL | LCK_CR | LCK_PR)) {
 605                 lock->l_readers++;
 606                 lu_ref_add_atomic(&lock->l_reference, "reader", lock);
 607         }
 608         if (mode & (LCK_EX | LCK_CW | LCK_PW | LCK_GROUP | LCK_COS)) {
 609                 lock->l_writers++;
 610                 lu_ref_add_atomic(&lock->l_reference, "writer", lock);
 611         }
 612         LDLM_LOCK_GET(lock);
 613         lu_ref_add_atomic(&lock->l_reference, "user", lock);
 614         LDLM_DEBUG(lock, "ldlm_lock_addref(%s)", ldlm_lockname[mode]);
 615 }
 616
 617 /**
 618  * Attempts to addref a lock, and fails if lock is already LDLM_FL_CBPENDING
 619  * or destroyed.
 620  *
 621  * \retval 0 success, lock was addref-ed
 622  *
 623  * \retval -EAGAIN lock is being canceled.
 624  */
 625 int ldlm_lock_addref_try(struct lustre_handle *lockh, __u32 mode)
 626 {
 627         struct ldlm_lock *lock;
 628         int               result;
 629
 630         result = -EAGAIN;
 631         lock = ldlm_handle2lock(lockh);
 632         if (lock != NULL) {
 633                 lock_res_and_lock(lock);
 634                 if (lock->l_readers != 0 || lock->l_writers != 0 ||
 635                     !(lock->l_flags & LDLM_FL_CBPENDING)) {
 636                         ldlm_lock_addref_internal_nolock(lock, mode);
 637                         result = 0;
 638                 }
 639                 unlock_res_and_lock(lock);
 640                 LDLM_LOCK_PUT(lock);
 641         }
 642         return result;
 643 }
 644
 645 /* only called for local locks */
 646 void ldlm_lock_addref_internal(struct ldlm_lock *lock, __u32 mode)
 647 {
 648         lock_res_and_lock(lock);
 649         ldlm_lock_addref_internal_nolock(lock, mode);
 650         unlock_res_and_lock(lock);
 651 }
 652
 653 /* only called in ldlm_flock_destroy and for local locks.
 654  *  * for LDLM_FLOCK type locks, l_blocking_ast is null, and
 655  *   * ldlm_lock_remove_from_lru() does nothing, it is safe
 656  *    * for ldlm_flock_destroy usage by dropping some code */
 657 void ldlm_lock_decref_internal_nolock(struct ldlm_lock *lock, __u32 mode)
 658 {
 659         LDLM_DEBUG(lock, "ldlm_lock_decref(%s)", ldlm_lockname[mode]);
 660         if (mode & (LCK_NL | LCK_CR | LCK_PR)) {
 661                 LASSERT(lock->l_readers > 0);
 662                 lu_ref_del(&lock->l_reference, "reader", lock);
 663                 lock->l_readers--;
 664         }
 665         if (mode & (LCK_EX | LCK_CW | LCK_PW | LCK_GROUP | LCK_COS)) {
 666                 LASSERT(lock->l_writers > 0);
 667                 lu_ref_del(&lock->l_reference, "writer", lock);
 668                 lock->l_writers--;
 669         }
 670
 671         lu_ref_del(&lock->l_reference, "user", lock);
 672         LDLM_LOCK_RELEASE(lock);    /* matches the LDLM_LOCK_GET() in addref */
 673 }
 674
 675 void ldlm_lock_decref_internal(struct ldlm_lock *lock, __u32 mode)
 676 {
 677         struct ldlm_namespace *ns;
 678         ENTRY;
 679
 680         lock_res_and_lock(lock);
 681
 682         ns = ldlm_lock_to_ns(lock);
 683
 684         ldlm_lock_decref_internal_nolock(lock, mode);
 685
 686         if (lock->l_flags & LDLM_FL_LOCAL &&
 687             !lock->l_readers && !lock->l_writers) {
 688                 /* If this is a local lock on a server namespace and this was
 689                  * the last reference, cancel the lock. */
 690                 CDEBUG(D_INFO, "forcing cancel of local lock\n");
 691                 lock->l_flags |= LDLM_FL_CBPENDING;
 692         }
 693
 694         if (!lock->l_readers && !lock->l_writers &&
 695             (lock->l_flags & LDLM_FL_CBPENDING)) {
 696                 /* If we received a blocked AST and this was the last reference,
 697                  * run the callback. */
 698                 if (ns_is_server(ns) && lock->l_export)
 699                         CERROR("FL_CBPENDING set on non-local lock--just a "
 700                                "warning\n");
 701
 702                 LDLM_DEBUG(lock, "final decref done on cbpending lock");
 703
 704                 LDLM_LOCK_GET(lock); /* dropped by bl thread */
 705                 ldlm_lock_remove_from_lru(lock);
 706                 unlock_res_and_lock(lock);
 707
 708                 if (lock->l_flags & LDLM_FL_FAIL_LOC)
 709                         OBD_RACE(OBD_FAIL_LDLM_CP_BL_RACE);
 710
 711                 if ((lock->l_flags & LDLM_FL_ATOMIC_CB) ||
 712                     ldlm_bl_to_thread_lock(ns, NULL, lock) != 0)
 713                         ldlm_handle_bl_callback(ns, NULL, lock);
 714         } else if (ns_is_client(ns) &&
 715                    !lock->l_readers && !lock->l_writers &&
 716                    !(lock->l_flags & LDLM_FL_BL_AST)) {
 717                 /* If this is a client-side namespace and this was the last
 718                  * reference, put it on the LRU. */
 719                 ldlm_lock_add_to_lru(lock);
 720                 unlock_res_and_lock(lock);
 721
 722                 if (lock->l_flags & LDLM_FL_FAIL_LOC)
 723                         OBD_RACE(OBD_FAIL_LDLM_CP_BL_RACE);
 724
 725                 /* Call ldlm_cancel_lru() only if EARLY_CANCEL and LRU RESIZE
 726                  * are not supported by the server, otherwise, it is done on
 727                  * enqueue. */
 728                 if (!exp_connect_cancelset(lock->l_conn_export) &&
 729                     !ns_connect_lru_resize(ns))
 730                         ldlm_cancel_lru(ns, 0, LDLM_ASYNC, 0);
 731         } else {
 732                 unlock_res_and_lock(lock);
 733         }
 734
 735         EXIT;
 736 }
 737
 738 void ldlm_lock_decref(struct lustre_handle *lockh, __u32 mode)
 739 {
 740         struct ldlm_lock *lock = __ldlm_handle2lock(lockh, 0);
 741         LASSERTF(lock != NULL, "Non-existing lock: "LPX64"\n", lockh->cookie);
 742         ldlm_lock_decref_internal(lock, mode);
 743         LDLM_LOCK_PUT(lock);
 744 }
 745
 746 /* This will drop a lock reference and mark it for destruction, but will not
 747  * necessarily cancel the lock before returning. */
 748 void ldlm_lock_decref_and_cancel(struct lustre_handle *lockh, __u32 mode)
 749 {
 750         struct ldlm_lock *lock = __ldlm_handle2lock(lockh, 0);
 751         ENTRY;
 752
 753         LASSERT(lock != NULL);
 754
 755         LDLM_DEBUG(lock, "ldlm_lock_decref(%s)", ldlm_lockname[mode]);
 756         lock_res_and_lock(lock);
 757         lock->l_flags |= LDLM_FL_CBPENDING;
 758         unlock_res_and_lock(lock);
 759         ldlm_lock_decref_internal(lock, mode);
 760         LDLM_LOCK_PUT(lock);
 761 }
 762
 763 struct sl_insert_point {
 764         cfs_list_t *res_link;
 765         cfs_list_t *mode_link;
 766         cfs_list_t *policy_link;
 767 };
 768
 769 /*
 770  * search_granted_lock
 771  *
 772  * Description:
 773  *      Finds a position to insert the new lock.
 774  * Parameters:
 775  *      queue [input]:  the granted list where search acts on;
 776  *      req [input]:    the lock whose position to be located;
 777  *      prev [output]:  positions within 3 lists to insert @req to
 778  * Return Value:
 779  *      filled @prev
 780  * NOTE: called by
 781  *  - ldlm_grant_lock_with_skiplist
 782  */
 783 static void search_granted_lock(cfs_list_t *queue,
 784                                 struct ldlm_lock *req,
 785                                 struct sl_insert_point *prev)
 786 {
 787         cfs_list_t *tmp;
 788         struct ldlm_lock *lock, *mode_end, *policy_end;
 789         ENTRY;
 790
 791         cfs_list_for_each(tmp, queue) {
 792                 lock = cfs_list_entry(tmp, struct ldlm_lock, l_res_link);
 793
 794                 mode_end = cfs_list_entry(lock->l_sl_mode.prev,
 795                                           struct ldlm_lock, l_sl_mode);
 796
 797                 if (lock->l_req_mode != req->l_req_mode) {
 798                         /* jump to last lock of mode group */
 799                         tmp = &mode_end->l_res_link;
 800                         continue;
 801                 }
 802
 803                 /* suitable mode group is found */
 804                 if (lock->l_resource->lr_type == LDLM_PLAIN) {
 805                         /* insert point is last lock of the mode group */
 806                         prev->res_link = &mode_end->l_res_link;
 807                         prev->mode_link = &mode_end->l_sl_mode;
 808                         prev->policy_link = &req->l_sl_policy;
 809                         EXIT;
 810                         return;
 811                 } else if (lock->l_resource->lr_type == LDLM_IBITS) {
 812                         for (;;) {
 813                                 policy_end =
 814                                         cfs_list_entry(lock->l_sl_policy.prev,
 815                                                        struct ldlm_lock,
 816                                                        l_sl_policy);
 817
 818                                 if (lock->l_policy_data.l_inodebits.bits ==
 819                                     req->l_policy_data.l_inodebits.bits) {
 820                                         /* insert point is last lock of
 821                                          * the policy group */
 822                                         prev->res_link =
 823                                                 &policy_end->l_res_link;
 824                                         prev->mode_link =
 825                                                 &policy_end->l_sl_mode;
 826                                         prev->policy_link =
 827                                                 &policy_end->l_sl_policy;
 828                                         EXIT;
 829                                         return;
 830                                 }
 831
 832                                 if (policy_end == mode_end)
 833                                         /* done with mode group */
 834                                         break;
 835
 836                                 /* go to next policy group within mode group */
 837                                 tmp = policy_end->l_res_link.next;
 838                                 lock = cfs_list_entry(tmp, struct ldlm_lock,
 839                                                       l_res_link);
 840                         }  /* loop over policy groups within the mode group */
 841
 842                         /* insert point is last lock of the mode group,
 843                          * new policy group is started */
 844                         prev->res_link = &mode_end->l_res_link;
 845                         prev->mode_link = &mode_end->l_sl_mode;
 846                         prev->policy_link = &req->l_sl_policy;
 847                         EXIT;
 848                         return;
 849                 } else {
 850                         LDLM_ERROR(lock,"is not LDLM_PLAIN or LDLM_IBITS lock");
 851                         LBUG();
 852                 }
 853         }
 854
 855         /* insert point is last lock on the queue,
 856          * new mode group and new policy group are started */
 857         prev->res_link = queue->prev;
 858         prev->mode_link = &req->l_sl_mode;
 859         prev->policy_link = &req->l_sl_policy;
 860         EXIT;
 861         return;
 862 }
 863
 864 static void ldlm_granted_list_add_lock(struct ldlm_lock *lock,
 865                                        struct sl_insert_point *prev)
 866 {
 867         struct ldlm_resource *res = lock->l_resource;
 868         ENTRY;
 869
 870         check_res_locked(res);
 871
 872         ldlm_resource_dump(D_INFO, res);
 873         CDEBUG(D_OTHER, "About to add this lock:\n");
 874         ldlm_lock_dump(D_OTHER, lock, 0);
 875
 876         if (lock->l_destroyed) {
 877                 CDEBUG(D_OTHER, "Lock destroyed, not adding to resource\n");
 878                 return;
 879         }
 880
 881         LASSERT(cfs_list_empty(&lock->l_res_link));
 882         LASSERT(cfs_list_empty(&lock->l_sl_mode));
 883         LASSERT(cfs_list_empty(&lock->l_sl_policy));
 884
 885         cfs_list_add(&lock->l_res_link, prev->res_link);
 886         cfs_list_add(&lock->l_sl_mode, prev->mode_link);
 887         cfs_list_add(&lock->l_sl_policy, prev->policy_link);
 888
 889         EXIT;
 890 }
 891
 892 static void ldlm_grant_lock_with_skiplist(struct ldlm_lock *lock)
 893 {
 894         struct sl_insert_point prev;
 895         ENTRY;
 896
 897         LASSERT(lock->l_req_mode == lock->l_granted_mode);
 898
 899         search_granted_lock(&lock->l_resource->lr_granted, lock, &prev);
 900         ldlm_granted_list_add_lock(lock, &prev);
 901         EXIT;
 902 }
 903
 904 /* NOTE: called by
 905  *  - ldlm_lock_enqueue
 906  *  - ldlm_reprocess_queue
 907  *  - ldlm_lock_convert
 908  *
 909  * must be called with lr_lock held
 910  */
 911 void ldlm_grant_lock(struct ldlm_lock *lock, cfs_list_t *work_list)
 912 {
 913         struct ldlm_resource *res = lock->l_resource;
 914         ENTRY;
 915
 916         check_res_locked(res);
 917
 918         lock->l_granted_mode = lock->l_req_mode;
 919         if (res->lr_type == LDLM_PLAIN || res->lr_type == LDLM_IBITS)
 920                 ldlm_grant_lock_with_skiplist(lock);
 921         else if (res->lr_type == LDLM_EXTENT)
 922                 ldlm_extent_add_lock(res, lock);
 923         else
 924                 ldlm_resource_add_lock(res, &res->lr_granted, lock);
 925
 926         if (lock->l_granted_mode < res->lr_most_restr)
 927                 res->lr_most_restr = lock->l_granted_mode;
 928
 929         if (work_list && lock->l_completion_ast != NULL)
 930                 ldlm_add_ast_work_item(lock, NULL, work_list);
 931
 932         ldlm_pool_add(&ldlm_res_to_ns(res)->ns_pool, lock);
 933         EXIT;
 934 }
 935
 936 /* returns a referenced lock or NULL.  See the flag descriptions below, in the
 937  * comment above ldlm_lock_match */
 938 static struct ldlm_lock *search_queue(cfs_list_t *queue,
 939                                       ldlm_mode_t *mode,
 940                                       ldlm_policy_data_t *policy,
 941                                       struct ldlm_lock *old_lock,
 942                                       int flags, int unref)
 943 {
 944         struct ldlm_lock *lock;
 945         cfs_list_t       *tmp;
 946
 947         cfs_list_for_each(tmp, queue) {
 948                 ldlm_mode_t match;
 949
 950                 lock = cfs_list_entry(tmp, struct ldlm_lock, l_res_link);
 951
 952                 if (lock == old_lock)
 953                         break;
 954
 955                 /* llite sometimes wants to match locks that will be
 956                  * canceled when their users drop, but we allow it to match
 957                  * if it passes in CBPENDING and the lock still has users.
 958                  * this is generally only going to be used by children
 959                  * whose parents already hold a lock so forward progress
 960                  * can still happen. */
 961                 if (lock->l_flags & LDLM_FL_CBPENDING &&
 962                     !(flags & LDLM_FL_CBPENDING))
 963                         continue;
 964                 if (!unref && lock->l_flags & LDLM_FL_CBPENDING &&
 965                     lock->l_readers == 0 && lock->l_writers == 0)
 966                         continue;
 967
 968                 if (!(lock->l_req_mode & *mode))
 969                         continue;
 970                 match = lock->l_req_mode;
 971
 972                 if (lock->l_resource->lr_type == LDLM_EXTENT &&
 973                     (lock->l_policy_data.l_extent.start >
 974                      policy->l_extent.start ||
 975                      lock->l_policy_data.l_extent.end < policy->l_extent.end))
 976                         continue;
 977
 978                 if (unlikely(match == LCK_GROUP) &&
 979                     lock->l_resource->lr_type == LDLM_EXTENT &&
 980                     lock->l_policy_data.l_extent.gid != policy->l_extent.gid)
 981                         continue;
 982
 983                 /* We match if we have existing lock with same or wider set
 984                    of bits. */
 985                 if (lock->l_resource->lr_type == LDLM_IBITS &&
 986                      ((lock->l_policy_data.l_inodebits.bits &
 987                       policy->l_inodebits.bits) !=
 988                       policy->l_inodebits.bits))
 989                         continue;
 990
 991                 if (!unref &&
 992                     (lock->l_destroyed || (lock->l_flags & LDLM_FL_FAILED)))
 993                         continue;
 994
 995                 if ((flags & LDLM_FL_LOCAL_ONLY) &&
 996                     !(lock->l_flags & LDLM_FL_LOCAL))
 997                         continue;
 998
 999                 if (flags & LDLM_FL_TEST_LOCK) {
1000                         LDLM_LOCK_GET(lock);
1001                         ldlm_lock_touch_in_lru(lock);
1002                 } else {
1003                         ldlm_lock_addref_internal_nolock(lock, match);
1004                 }
1005                 *mode = match;
1006                 return lock;
1007         }
1008
1009         return NULL;
1010 }
1011
1012 void ldlm_lock_allow_match_locked(struct ldlm_lock *lock)
1013 {
1014         lock->l_flags |= LDLM_FL_LVB_READY;
1015         cfs_waitq_signal(&lock->l_waitq);
1016 }
1017
1018 void ldlm_lock_allow_match(struct ldlm_lock *lock)
1019 {
1020         lock_res_and_lock(lock);
1021         ldlm_lock_allow_match_locked(lock);
1022         unlock_res_and_lock(lock);
1023 }
1024
1025 /* Can be called in two ways:
1026  *
1027  * If 'ns' is NULL, then lockh describes an existing lock that we want to look
1028  * for a duplicate of.
1029  *
1030  * Otherwise, all of the fields must be filled in, to match against.
1031  *
1032  * If 'flags' contains LDLM_FL_LOCAL_ONLY, then only match local locks on the
1033  *     server (ie, connh is NULL)
1034  * If 'flags' contains LDLM_FL_BLOCK_GRANTED, then only locks on the granted
1035  *     list will be considered
1036  * If 'flags' contains LDLM_FL_CBPENDING, then locks that have been marked
1037  *     to be canceled can still be matched as long as they still have reader
1038  *     or writer refernces
1039  * If 'flags' contains LDLM_FL_TEST_LOCK, then don't actually reference a lock,
1040  *     just tell us if we would have matched.
1041  *
1042  * Returns 1 if it finds an already-existing lock that is compatible; in this
1043  * case, lockh is filled in with a addref()ed lock
1044  *
1045  * we also check security context, if that failed we simply return 0 (to keep
1046  * caller code unchanged), the context failure will be discovered by caller
1047  * sometime later.
1048  */
1049 ldlm_mode_t ldlm_lock_match(struct ldlm_namespace *ns, int flags,
1050                             const struct ldlm_res_id *res_id, ldlm_type_t type,
1051                             ldlm_policy_data_t *policy, ldlm_mode_t mode,
1052                             struct lustre_handle *lockh, int unref)
1053 {
1054         struct ldlm_resource *res;
1055         struct ldlm_lock *lock, *old_lock = NULL;
1056         int rc = 0;
1057         ENTRY;
1058
1059         if (ns == NULL) {
1060                 old_lock = ldlm_handle2lock(lockh);
1061                 LASSERT(old_lock);
1062
1063                 ns = ldlm_lock_to_ns(old_lock);
1064                 res_id = &old_lock->l_resource->lr_name;
1065                 type = old_lock->l_resource->lr_type;
1066                 mode = old_lock->l_req_mode;
1067         }
1068
1069         res = ldlm_resource_get(ns, NULL, res_id, type, 0);
1070         if (res == NULL) {
1071                 LASSERT(old_lock == NULL);
1072                 RETURN(0);
1073         }
1074
1075         LDLM_RESOURCE_ADDREF(res);
1076         lock_res(res);
1077
1078         lock = search_queue(&res->lr_granted, &mode, policy, old_lock,
1079                             flags, unref);
1080         if (lock != NULL)
1081                 GOTO(out, rc = 1);
1082         if (flags & LDLM_FL_BLOCK_GRANTED)
1083                 GOTO(out, rc = 0);
1084         lock = search_queue(&res->lr_converting, &mode, policy, old_lock,
1085                             flags, unref);
1086         if (lock != NULL)
1087                 GOTO(out, rc = 1);
1088         lock = search_queue(&res->lr_waiting, &mode, policy, old_lock,
1089                             flags, unref);
1090         if (lock != NULL)
1091                 GOTO(out, rc = 1);
1092
1093         EXIT;
1094  out:
1095         unlock_res(res);
1096         LDLM_RESOURCE_DELREF(res);
1097         ldlm_resource_putref(res);
1098
1099         if (lock) {
1100                 ldlm_lock2handle(lock, lockh);
1101                 if ((flags & LDLM_FL_LVB_READY) &&
1102                     (!(lock->l_flags & LDLM_FL_LVB_READY))) {
1103                         struct l_wait_info lwi;
1104                         if (lock->l_completion_ast) {
1105                                 int err = lock->l_completion_ast(lock,
1106                                                           LDLM_FL_WAIT_NOREPROC,
1107                                                                  NULL);
1108                                 if (err) {
1109                                         if (flags & LDLM_FL_TEST_LOCK)
1110                                                 LDLM_LOCK_RELEASE(lock);
1111                                         else
1112                                                 ldlm_lock_decref_internal(lock,
1113                                                                           mode);
1114                                         rc = 0;
1115                                         goto out2;
1116                                 }
1117                         }
1118
1119                         lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(obd_timeout),
1120                                                NULL, LWI_ON_SIGNAL_NOOP, NULL);
1121
1122                         /* XXX FIXME see comment on CAN_MATCH in lustre_dlm.h */
1123                         l_wait_event(lock->l_waitq,
1124                                      (lock->l_flags & LDLM_FL_LVB_READY), &lwi);
1125                 }
1126         }
1127  out2:
1128         if (rc) {
1129                 LDLM_DEBUG(lock, "matched ("LPU64" "LPU64")",
1130                            (type == LDLM_PLAIN || type == LDLM_IBITS) ?
1131                                 res_id->name[2] : policy->l_extent.start,
1132                            (type == LDLM_PLAIN || type == LDLM_IBITS) ?
1133                                 res_id->name[3] : policy->l_extent.end);
1134
1135                 /* check user's security context */
1136                 if (lock->l_conn_export &&
1137                     sptlrpc_import_check_ctx(
1138                                 class_exp2cliimp(lock->l_conn_export))) {
1139                         if (!(flags & LDLM_FL_TEST_LOCK))
1140                                 ldlm_lock_decref_internal(lock, mode);
1141                         rc = 0;
1142                 }
1143
1144                 if (flags & LDLM_FL_TEST_LOCK)
1145                         LDLM_LOCK_RELEASE(lock);
1146
1147         } else if (!(flags & LDLM_FL_TEST_LOCK)) {/*less verbose for test-only*/
1148                 LDLM_DEBUG_NOLOCK("not matched ns %p type %u mode %u res "
1149                                   LPU64"/"LPU64" ("LPU64" "LPU64")", ns,
1150                                   type, mode, res_id->name[0], res_id->name[1],
1151                                   (type == LDLM_PLAIN || type == LDLM_IBITS) ?
1152                                         res_id->name[2] :policy->l_extent.start,
1153                                   (type == LDLM_PLAIN || type == LDLM_IBITS) ?
1154                                         res_id->name[3] : policy->l_extent.end);
1155         }
1156         if (old_lock)
1157                 LDLM_LOCK_PUT(old_lock);
1158
1159         return rc ? mode : 0;
1160 }
1161
1162 /* Returns a referenced lock */
1163 struct ldlm_lock *ldlm_lock_create(struct ldlm_namespace *ns,
1164                                    const struct ldlm_res_id *res_id,
1165                                    ldlm_type_t type,
1166                                    ldlm_mode_t mode,
1167                                    const struct ldlm_callback_suite *cbs,
1168                                    void *data, __u32 lvb_len)
1169 {
1170         struct ldlm_lock *lock;
1171         struct ldlm_resource *res;
1172         ENTRY;
1173
1174         res = ldlm_resource_get(ns, NULL, res_id, type, 1);
1175         if (res == NULL)
1176                 RETURN(NULL);
1177
1178         lock = ldlm_lock_new(res);
1179         ldlm_resource_putref(res);
1180
1181         if (lock == NULL)
1182                 RETURN(NULL);
1183
1184         lock->l_req_mode = mode;
1185         lock->l_ast_data = data;
1186         lock->l_pid = cfs_curproc_pid();
1187         if (cbs) {
1188                 lock->l_blocking_ast = cbs->lcs_blocking;
1189                 lock->l_completion_ast = cbs->lcs_completion;
1190                 lock->l_glimpse_ast = cbs->lcs_glimpse;
1191                 lock->l_weigh_ast = cbs->lcs_weigh;
1192         }
1193
1194         lock->l_tree_node = NULL;
1195         /* if this is the extent lock, allocate the interval tree node */
1196         if (type == LDLM_EXTENT) {
1197                 if (ldlm_interval_alloc(lock) == NULL)
1198                         GOTO(out, 0);
1199         }
1200
1201         if (lvb_len) {
1202                 lock->l_lvb_len = lvb_len;
1203                 OBD_ALLOC(lock->l_lvb_data, lvb_len);
1204                 if (lock->l_lvb_data == NULL)
1205                         GOTO(out, 0);
1206         }
1207
1208         if (OBD_FAIL_CHECK(OBD_FAIL_LDLM_NEW_LOCK))
1209                 GOTO(out, 0);
1210
1211         RETURN(lock);
1212
1213 out:
1214         ldlm_lock_destroy(lock);
1215         LDLM_LOCK_RELEASE(lock);
1216         return NULL;
1217 }
1218
1219 ldlm_error_t ldlm_lock_enqueue(struct ldlm_namespace *ns,
1220                                struct ldlm_lock **lockp,
1221                                void *cookie, int *flags)
1222 {
1223         struct ldlm_lock *lock = *lockp;
1224         struct ldlm_resource *res = lock->l_resource;
1225         int local = ns_is_client(ldlm_res_to_ns(res));
1226         ldlm_processing_policy policy;
1227         ldlm_error_t rc = ELDLM_OK;
1228         struct ldlm_interval *node = NULL;
1229         ENTRY;
1230
1231         lock->l_last_activity = cfs_time_current_sec();
1232         /* policies are not executed on the client or during replay */
1233         if ((*flags & (LDLM_FL_HAS_INTENT|LDLM_FL_REPLAY)) == LDLM_FL_HAS_INTENT
1234             && !local && ns->ns_policy) {
1235                 rc = ns->ns_policy(ns, lockp, cookie, lock->l_req_mode, *flags,
1236                                    NULL);
1237                 if (rc == ELDLM_LOCK_REPLACED) {
1238                         /* The lock that was returned has already been granted,
1239                          * and placed into lockp.  If it's not the same as the
1240                          * one we passed in, then destroy the old one and our
1241                          * work here is done. */
1242                         if (lock != *lockp) {
1243                                 ldlm_lock_destroy(lock);
1244                                 LDLM_LOCK_RELEASE(lock);
1245                         }
1246                         *flags |= LDLM_FL_LOCK_CHANGED;
1247                         RETURN(0);
1248                 } else if (rc != ELDLM_OK ||
1249                            (rc == ELDLM_OK && (*flags & LDLM_FL_INTENT_ONLY))) {
1250                         ldlm_lock_destroy(lock);
1251                         RETURN(rc);
1252                 }
1253         }
1254
1255         /* For a replaying lock, it might be already in granted list. So
1256          * unlinking the lock will cause the interval node to be freed, we
1257          * have to allocate the interval node early otherwise we can't regrant
1258          * this lock in the future. - jay */
1259         if (!local && (*flags & LDLM_FL_REPLAY) && res->lr_type == LDLM_EXTENT)
1260                 OBD_SLAB_ALLOC_PTR_GFP(node, ldlm_interval_slab, CFS_ALLOC_IO);
1261
1262         lock_res_and_lock(lock);
1263         if (local && lock->l_req_mode == lock->l_granted_mode) {
1264                 /* The server returned a blocked lock, but it was granted
1265                  * before we got a chance to actually enqueue it.  We don't
1266                  * need to do anything else. */
1267                 *flags &= ~(LDLM_FL_BLOCK_GRANTED |
1268                             LDLM_FL_BLOCK_CONV | LDLM_FL_BLOCK_WAIT);
1269                 GOTO(out, ELDLM_OK);
1270         }
1271
1272         ldlm_resource_unlink_lock(lock);
1273         if (res->lr_type == LDLM_EXTENT && lock->l_tree_node == NULL) {
1274                 if (node == NULL) {
1275                         ldlm_lock_destroy_nolock(lock);
1276                         GOTO(out, rc = -ENOMEM);
1277                 }
1278
1279                 CFS_INIT_LIST_HEAD(&node->li_group);
1280                 ldlm_interval_attach(node, lock);
1281                 node = NULL;
1282         }
1283
1284         /* Some flags from the enqueue want to make it into the AST, via the
1285          * lock's l_flags. */
1286         lock->l_flags |= *flags & LDLM_AST_DISCARD_DATA;
1287
1288         /* This distinction between local lock trees is very important; a client
1289          * namespace only has information about locks taken by that client, and
1290          * thus doesn't have enough information to decide for itself if it can
1291          * be granted (below).  In this case, we do exactly what the server
1292          * tells us to do, as dictated by the 'flags'.
1293          *
1294          * We do exactly the same thing during recovery, when the server is
1295          * more or less trusting the clients not to lie.
1296          *
1297          * FIXME (bug 268): Detect obvious lies by checking compatibility in
1298          * granted/converting queues. */
1299         if (local) {
1300                 if (*flags & LDLM_FL_BLOCK_CONV)
1301                         ldlm_resource_add_lock(res, &res->lr_converting, lock);
1302                 else if (*flags & (LDLM_FL_BLOCK_WAIT | LDLM_FL_BLOCK_GRANTED))
1303                         ldlm_resource_add_lock(res, &res->lr_waiting, lock);
1304                 else
1305                         ldlm_grant_lock(lock, NULL);
1306                 GOTO(out, ELDLM_OK);
1307         } else if (*flags & LDLM_FL_REPLAY) {
1308                 if (*flags & LDLM_FL_BLOCK_CONV) {
1309                         ldlm_resource_add_lock(res, &res->lr_converting, lock);
1310                         GOTO(out, ELDLM_OK);
1311                 } else if (*flags & LDLM_FL_BLOCK_WAIT) {
1312                         ldlm_resource_add_lock(res, &res->lr_waiting, lock);
1313                         GOTO(out, ELDLM_OK);
1314                 } else if (*flags & LDLM_FL_BLOCK_GRANTED) {
1315                         ldlm_grant_lock(lock, NULL);
1316                         GOTO(out, ELDLM_OK);
1317                 }
1318                 /* If no flags, fall through to normal enqueue path. */
1319         }
1320
1321         policy = ldlm_processing_policy_table[res->lr_type];
1322         policy(lock, flags, 1, &rc, NULL);
1323         GOTO(out, rc);
1324 out:
1325         unlock_res_and_lock(lock);
1326         if (node)
1327                 OBD_SLAB_FREE(node, ldlm_interval_slab, sizeof(*node));
1328         return rc;
1329 }
1330
1331 /* Must be called with namespace taken: queue is waiting or converting. */
1332 int ldlm_reprocess_queue(struct ldlm_resource *res, cfs_list_t *queue,
1333                          cfs_list_t *work_list)
1334 {
1335         cfs_list_t *tmp, *pos;
1336         ldlm_processing_policy policy;
1337         int flags;
1338         int rc = LDLM_ITER_CONTINUE;
1339         ldlm_error_t err;
1340         ENTRY;
1341
1342         check_res_locked(res);
1343
1344         policy = ldlm_processing_policy_table[res->lr_type];
1345         LASSERT(policy);
1346
1347         cfs_list_for_each_safe(tmp, pos, queue) {
1348                 struct ldlm_lock *pending;
1349                 pending = cfs_list_entry(tmp, struct ldlm_lock, l_res_link);
1350
1351                 CDEBUG(D_INFO, "Reprocessing lock %p\n", pending);
1352
1353                 flags = 0;
1354                 rc = policy(pending, &flags, 0, &err, work_list);
1355                 if (rc != LDLM_ITER_CONTINUE)
1356                         break;
1357         }
1358
1359         RETURN(rc);
1360 }
1361
1362 /* Helper function for ldlm_run_ast_work().
1363  *
1364  * Send an existing rpc set specified by @arg->set and then
1365  * destroy it. Create new one if @do_create flag is set. */
1366 static void
1367 ldlm_send_and_maybe_create_set(struct ldlm_cb_set_arg *arg, int do_create)
1368 {
1369         ENTRY;
1370
1371         ptlrpc_set_wait(arg->set);
1372         if (arg->type == LDLM_BL_CALLBACK)
1373                 OBD_FAIL_TIMEOUT(OBD_FAIL_LDLM_GLIMPSE, 2);
1374         ptlrpc_set_destroy(arg->set);
1375
1376         if (do_create)
1377                 arg->set = ptlrpc_prep_set();
1378
1379         EXIT;
1380 }
1381
1382 static int
1383 ldlm_work_bl_ast_lock(cfs_list_t *tmp, struct ldlm_cb_set_arg *arg)
1384 {
1385         struct ldlm_lock_desc d;
1386         struct ldlm_lock *lock = cfs_list_entry(tmp, struct ldlm_lock,
1387                                                 l_bl_ast);
1388         ENTRY;
1389
1390         /* nobody should touch l_bl_ast */
1391         lock_res_and_lock(lock);
1392         cfs_list_del_init(&lock->l_bl_ast);
1393
1394         LASSERT(lock->l_flags & LDLM_FL_AST_SENT);
1395         LASSERT(lock->l_bl_ast_run == 0);
1396         LASSERT(lock->l_blocking_lock);
1397         lock->l_bl_ast_run++;
1398         unlock_res_and_lock(lock);
1399
1400         ldlm_lock2desc(lock->l_blocking_lock, &d);
1401
1402         lock->l_blocking_ast(lock, &d, (void *)arg,
1403                              LDLM_CB_BLOCKING);
1404         LDLM_LOCK_RELEASE(lock->l_blocking_lock);
1405         lock->l_blocking_lock = NULL;
1406         LDLM_LOCK_RELEASE(lock);
1407
1408         RETURN(1);
1409 }
1410
1411 static int
1412 ldlm_work_cp_ast_lock(cfs_list_t *tmp, struct ldlm_cb_set_arg *arg)
1413 {
1414         struct ldlm_lock *lock = cfs_list_entry(tmp, struct ldlm_lock, l_cp_ast);
1415         ldlm_completion_callback completion_callback;
1416         int rc = 0;
1417         ENTRY;
1418
1419         /* It's possible to receive a completion AST before we've set
1420          * the l_completion_ast pointer: either because the AST arrived
1421          * before the reply, or simply because there's a small race
1422          * window between receiving the reply and finishing the local
1423          * enqueue. (bug 842)
1424          *
1425          * This can't happen with the blocking_ast, however, because we
1426          * will never call the local blocking_ast until we drop our
1427          * reader/writer reference, which we won't do until we get the
1428          * reply and finish enqueueing. */
1429
1430         /* nobody should touch l_cp_ast */
1431         lock_res_and_lock(lock);
1432         cfs_list_del_init(&lock->l_cp_ast);
1433         LASSERT(lock->l_flags & LDLM_FL_CP_REQD);
1434         /* save l_completion_ast since it can be changed by
1435          * mds_intent_policy(), see bug 14225 */
1436         completion_callback = lock->l_completion_ast;
1437         lock->l_flags &= ~LDLM_FL_CP_REQD;
1438         unlock_res_and_lock(lock);
1439
1440         if (completion_callback != NULL) {
1441                 completion_callback(lock, 0, (void *)arg);
1442                 rc = 1;
1443         }
1444         LDLM_LOCK_RELEASE(lock);
1445
1446         RETURN(rc);
1447 }
1448
1449 static int
1450 ldlm_work_revoke_ast_lock(cfs_list_t *tmp, struct ldlm_cb_set_arg *arg)
1451 {
1452         struct ldlm_lock_desc desc;
1453         struct ldlm_lock *lock = cfs_list_entry(tmp, struct ldlm_lock,
1454                                                 l_rk_ast);
1455         ENTRY;
1456
1457         cfs_list_del_init(&lock->l_rk_ast);
1458
1459         /* the desc just pretend to exclusive */
1460         ldlm_lock2desc(lock, &desc);
1461         desc.l_req_mode = LCK_EX;
1462         desc.l_granted_mode = 0;
1463
1464         lock->l_blocking_ast(lock, &desc, (void*)arg, LDLM_CB_BLOCKING);
1465         LDLM_LOCK_RELEASE(lock);
1466
1467         RETURN(1);
1468 }
1469
1470 int ldlm_run_ast_work(cfs_list_t *rpc_list, ldlm_desc_ast_t ast_type)
1471 {
1472         struct ldlm_cb_set_arg arg;
1473         cfs_list_t *tmp, *pos;
1474         int (*work_ast_lock)(cfs_list_t *tmp, struct ldlm_cb_set_arg *arg);
1475         int ast_count;
1476         ENTRY;
1477
1478         if (cfs_list_empty(rpc_list))
1479                 RETURN(0);
1480
1481         arg.set = ptlrpc_prep_set();
1482         if (NULL == arg.set)
1483                 RETURN(-ERESTART);
1484         cfs_atomic_set(&arg.restart, 0);
1485         switch (ast_type) {
1486         case LDLM_WORK_BL_AST:
1487                 arg.type = LDLM_BL_CALLBACK;
1488                 work_ast_lock = ldlm_work_bl_ast_lock;
1489                 break;
1490         case LDLM_WORK_CP_AST:
1491                 arg.type = LDLM_CP_CALLBACK;
1492                 work_ast_lock = ldlm_work_cp_ast_lock;
1493                 break;
1494         case LDLM_WORK_REVOKE_AST:
1495                 arg.type = LDLM_BL_CALLBACK;
1496                 work_ast_lock = ldlm_work_revoke_ast_lock;
1497                 break;
1498         default:
1499                 LBUG();
1500         }
1501
1502         ast_count = 0;
1503         cfs_list_for_each_safe(tmp, pos, rpc_list) {
1504                 ast_count += work_ast_lock(tmp, &arg);
1505
1506                 /* Send the request set if it exceeds the PARALLEL_AST_LIMIT,
1507                  * and create a new set for requests that remained in
1508                  * @rpc_list */
1509                 if (unlikely(ast_count == PARALLEL_AST_LIMIT)) {
1510                         ldlm_send_and_maybe_create_set(&arg, 1);
1511                         ast_count = 0;
1512                 }
1513         }
1514
1515         if (ast_count > 0)
1516                 ldlm_send_and_maybe_create_set(&arg, 0);
1517         else
1518                 /* In case when number of ASTs is multiply of
1519                  * PARALLEL_AST_LIMIT or @rpc_list was initially empty,
1520                  * @arg.set must be destroyed here, otherwise we get
1521                  * write memory leaking. */
1522                 ptlrpc_set_destroy(arg.set);
1523
1524         RETURN(cfs_atomic_read(&arg.restart) ? -ERESTART : 0);
1525 }
1526
1527 static int reprocess_one_queue(struct ldlm_resource *res, void *closure)
1528 {
1529         ldlm_reprocess_all(res);
1530         return LDLM_ITER_CONTINUE;
1531 }
1532
1533 void ldlm_reprocess_all_ns(struct ldlm_namespace *ns)
1534 {
1535         cfs_list_t *tmp;
1536         int i, rc;
1537
1538         if (ns == NULL)
1539                 return;
1540
1541         ENTRY;
1542         cfs_spin_lock(&ns->ns_hash_lock);
1543         for (i = 0; i < RES_HASH_SIZE; i++) {
1544                 tmp = ns->ns_hash[i].next;
1545                 while (tmp != &(ns->ns_hash[i])) {
1546                         struct ldlm_resource *res =
1547                                 cfs_list_entry(tmp, struct ldlm_resource,
1548                                                lr_hash);
1549
1550                         ldlm_resource_getref(res);
1551                         cfs_spin_unlock(&ns->ns_hash_lock);
1552                         LDLM_RESOURCE_ADDREF(res);
1553
1554                         rc = reprocess_one_queue(res, NULL);
1555
1556                         LDLM_RESOURCE_DELREF(res);
1557                         cfs_spin_lock(&ns->ns_hash_lock);
1558                         tmp = tmp->next;
1559                         ldlm_resource_putref_locked(res);
1560
1561                         if (rc == LDLM_ITER_STOP)
1562                                 GOTO(out, rc);
1563                 }
1564         }
1565  out:
1566         cfs_spin_unlock(&ns->ns_hash_lock);
1567         EXIT;
1568 }
1569
1570 void ldlm_reprocess_all(struct ldlm_resource *res)
1571 {
1572         CFS_LIST_HEAD(rpc_list);
1573         int rc;
1574         ENTRY;
1575
1576         /* Local lock trees don't get reprocessed. */
1577         if (ns_is_client(ldlm_res_to_ns(res))) {
1578                 EXIT;
1579                 return;
1580         }
1581
1582  restart:
1583         lock_res(res);
1584         rc = ldlm_reprocess_queue(res, &res->lr_converting, &rpc_list);
1585         if (rc == LDLM_ITER_CONTINUE)
1586                 ldlm_reprocess_queue(res, &res->lr_waiting, &rpc_list);
1587         unlock_res(res);
1588
1589         rc = ldlm_run_ast_work(&rpc_list, LDLM_WORK_CP_AST);
1590         if (rc == -ERESTART) {
1591                 LASSERT(cfs_list_empty(&rpc_list));
1592                 goto restart;
1593         }
1594         EXIT;
1595 }
1596
1597 void ldlm_cancel_callback(struct ldlm_lock *lock)
1598 {
1599         check_res_locked(lock->l_resource);
1600         if (!(lock->l_flags & LDLM_FL_CANCEL)) {
1601                 lock->l_flags |= LDLM_FL_CANCEL;
1602                 if (lock->l_blocking_ast) {
1603                         // l_check_no_ns_lock(ns);
1604                         unlock_res_and_lock(lock);
1605                         lock->l_blocking_ast(lock, NULL, lock->l_ast_data,
1606                                              LDLM_CB_CANCELING);
1607                         lock_res_and_lock(lock);
1608                 } else {
1609                         LDLM_DEBUG(lock, "no blocking ast");
1610                 }
1611         }
1612         lock->l_flags |= LDLM_FL_BL_DONE;
1613 }
1614
1615 void ldlm_unlink_lock_skiplist(struct ldlm_lock *req)
1616 {
1617         if (req->l_resource->lr_type != LDLM_PLAIN &&
1618             req->l_resource->lr_type != LDLM_IBITS)
1619                 return;
1620
1621         cfs_list_del_init(&req->l_sl_policy);
1622         cfs_list_del_init(&req->l_sl_mode);
1623 }
1624
1625 void ldlm_lock_cancel(struct ldlm_lock *lock)
1626 {
1627         struct ldlm_resource *res;
1628         struct ldlm_namespace *ns;
1629         ENTRY;
1630
1631         lock_res_and_lock(lock);
1632
1633         res = lock->l_resource;
1634         ns  = ldlm_res_to_ns(res);
1635
1636         /* Please do not, no matter how tempting, remove this LBUG without
1637          * talking to me first. -phik */
1638         if (lock->l_readers || lock->l_writers) {
1639                 LDLM_ERROR(lock, "lock still has references");
1640                 LBUG();
1641         }
1642
1643         ldlm_del_waiting_lock(lock);
1644
1645         /* Releases cancel callback. */
1646         ldlm_cancel_callback(lock);
1647
1648         /* Yes, second time, just in case it was added again while we were
1649            running with no res lock in ldlm_cancel_callback */
1650         ldlm_del_waiting_lock(lock);
1651         ldlm_resource_unlink_lock(lock);
1652         ldlm_lock_destroy_nolock(lock);
1653
1654         if (lock->l_granted_mode == lock->l_req_mode)
1655                 ldlm_pool_del(&ns->ns_pool, lock);
1656
1657         /* Make sure we will not be called again for same lock what is possible
1658          * if not to zero out lock->l_granted_mode */
1659         lock->l_granted_mode = LCK_MINMODE;
1660         unlock_res_and_lock(lock);
1661
1662         EXIT;
1663 }
1664
1665 int ldlm_lock_set_data(struct lustre_handle *lockh, void *data)
1666 {
1667         struct ldlm_lock *lock = ldlm_handle2lock(lockh);
1668         ENTRY;
1669
1670         if (lock == NULL)
1671                 RETURN(-EINVAL);
1672
1673         lock->l_ast_data = data;
1674         LDLM_LOCK_PUT(lock);
1675         RETURN(0);
1676 }
1677
1678 int ldlm_cancel_locks_for_export_cb(cfs_hash_t *hs, cfs_hash_bd_t *bd,
1679                                     cfs_hlist_node_t *hnode, void *data)
1680
1681 {
1682         struct obd_export    *exp  = data;
1683         struct ldlm_lock     *lock = cfs_hash_object(hs, hnode);
1684         struct ldlm_resource *res;
1685
1686         res = ldlm_resource_getref(lock->l_resource);
1687         LDLM_LOCK_GET(lock);
1688
1689         LDLM_DEBUG(lock, "export %p", exp);
1690         ldlm_res_lvbo_update(res, NULL, 1);
1691         ldlm_lock_cancel(lock);
1692         ldlm_reprocess_all(res);
1693         ldlm_resource_putref(res);
1694         LDLM_LOCK_RELEASE(lock);
1695         return 0;
1696 }
1697
1698 void ldlm_cancel_locks_for_export(struct obd_export *exp)
1699 {
1700         cfs_hash_for_each_empty(exp->exp_lock_hash,
1701                                 ldlm_cancel_locks_for_export_cb, exp);
1702 }
1703
1704 /**
1705  * Downgrade an exclusive lock.
1706  *
1707  * A fast variant of ldlm_lock_convert for convertion of exclusive
1708  * locks. The convertion is always successful.
1709  *
1710  * \param lock A lock to convert
1711  * \param new_mode new lock mode
1712  */
1713 void ldlm_lock_downgrade(struct ldlm_lock *lock, int new_mode)
1714 {
1715         struct ldlm_namespace *ns;
1716         ENTRY;
1717
1718         LASSERT(lock->l_granted_mode & (LCK_PW | LCK_EX));
1719         LASSERT(new_mode == LCK_COS);
1720
1721         lock_res_and_lock(lock);
1722         ldlm_resource_unlink_lock(lock);
1723         /*
1724          * Remove the lock from pool as it will be added again in
1725          * ldlm_grant_lock() called below.
1726          */
1727         ns = ldlm_lock_to_ns(lock);
1728         ldlm_pool_del(&ns->ns_pool, lock);
1729
1730         lock->l_req_mode = new_mode;
1731         ldlm_grant_lock(lock, NULL);
1732         unlock_res_and_lock(lock);
1733         ldlm_reprocess_all(lock->l_resource);
1734
1735         EXIT;
1736 }
1737
1738 struct ldlm_resource *ldlm_lock_convert(struct ldlm_lock *lock, int new_mode,
1739                                         __u32 *flags)
1740 {
1741         CFS_LIST_HEAD(rpc_list);
1742         struct ldlm_resource *res;
1743         struct ldlm_namespace *ns;
1744         int granted = 0;
1745         int old_mode, rc;
1746         struct sl_insert_point prev;
1747         ldlm_error_t err;
1748         struct ldlm_interval *node;
1749         ENTRY;
1750
1751         if (new_mode == lock->l_granted_mode) { // No changes? Just return.
1752                 *flags |= LDLM_FL_BLOCK_GRANTED;
1753                 RETURN(lock->l_resource);
1754         }
1755
1756         /* I can't check the type of lock here because the bitlock of lock
1757          * is not held here, so do the allocation blindly. -jay */
1758         OBD_SLAB_ALLOC_PTR_GFP(node, ldlm_interval_slab, CFS_ALLOC_IO);
1759         if (node == NULL)  /* Actually, this causes EDEADLOCK to be returned */
1760                 RETURN(NULL);
1761
1762         LASSERTF((new_mode == LCK_PW && lock->l_granted_mode == LCK_PR),
1763                  "new_mode %u, granted %u\n", new_mode, lock->l_granted_mode);
1764
1765         lock_res_and_lock(lock);
1766
1767         res = lock->l_resource;
1768         ns  = ldlm_res_to_ns(res);
1769
1770         old_mode = lock->l_req_mode;
1771         lock->l_req_mode = new_mode;
1772         if (res->lr_type == LDLM_PLAIN || res->lr_type == LDLM_IBITS) {
1773                 /* remember the lock position where the lock might be
1774                  * added back to the granted list later and also
1775                  * remember the join mode for skiplist fixing. */
1776                 prev.res_link = lock->l_res_link.prev;
1777                 prev.mode_link = lock->l_sl_mode.prev;
1778                 prev.policy_link = lock->l_sl_policy.prev;
1779                 ldlm_resource_unlink_lock(lock);
1780         } else {
1781                 ldlm_resource_unlink_lock(lock);
1782                 if (res->lr_type == LDLM_EXTENT) {
1783                         /* FIXME: ugly code, I have to attach the lock to a
1784                          * interval node again since perhaps it will be granted
1785                          * soon */
1786                         CFS_INIT_LIST_HEAD(&node->li_group);
1787                         ldlm_interval_attach(node, lock);
1788                         node = NULL;
1789                 }
1790         }
1791
1792         /*
1793          * Remove old lock from the pool before adding the lock with new
1794          * mode below in ->policy()
1795          */
1796         ldlm_pool_del(&ns->ns_pool, lock);
1797
1798         /* If this is a local resource, put it on the appropriate list. */
1799         if (ns_is_client(ldlm_res_to_ns(res))) {
1800                 if (*flags & (LDLM_FL_BLOCK_CONV | LDLM_FL_BLOCK_GRANTED)) {
1801                         ldlm_resource_add_lock(res, &res->lr_converting, lock);
1802                 } else {
1803                         /* This should never happen, because of the way the
1804                          * server handles conversions. */
1805                         LDLM_ERROR(lock, "Erroneous flags %d on local lock\n",
1806                                    *flags);
1807                         LBUG();
1808
1809                         ldlm_grant_lock(lock, &rpc_list);
1810                         granted = 1;
1811                         /* FIXME: completion handling not with ns_lock held ! */
1812                         if (lock->l_completion_ast)
1813                                 lock->l_completion_ast(lock, 0, NULL);
1814                 }
1815         } else {
1816                 int pflags = 0;
1817                 ldlm_processing_policy policy;
1818                 policy = ldlm_processing_policy_table[res->lr_type];
1819                 rc = policy(lock, &pflags, 0, &err, &rpc_list);
1820                 if (rc == LDLM_ITER_STOP) {
1821                         lock->l_req_mode = old_mode;
1822                         if (res->lr_type == LDLM_EXTENT)
1823                                 ldlm_extent_add_lock(res, lock);
1824                         else
1825                                 ldlm_granted_list_add_lock(lock, &prev);
1826
1827                         res = NULL;
1828                 } else {
1829                         *flags |= LDLM_FL_BLOCK_GRANTED;
1830                         granted = 1;
1831                 }
1832         }
1833         unlock_res_and_lock(lock);
1834
1835         if (granted)
1836                 ldlm_run_ast_work(&rpc_list, LDLM_WORK_CP_AST);
1837         if (node)
1838                 OBD_SLAB_FREE(node, ldlm_interval_slab, sizeof(*node));
1839         RETURN(res);
1840 }
1841
1842 void ldlm_lock_dump(int level, struct ldlm_lock *lock, int pos)
1843 {
1844         struct obd_device *obd = NULL;
1845
1846         if (!((libcfs_debug | D_ERROR) & level))
1847                 return;
1848
1849         if (!lock) {
1850                 CDEBUG(level, "  NULL LDLM lock\n");
1851                 return;
1852         }
1853
1854         CDEBUG(level," -- Lock dump: %p/"LPX64" (rc: %d) (pos: %d) (pid: %d)\n",
1855                lock, lock->l_handle.h_cookie, cfs_atomic_read(&lock->l_refc),
1856                pos, lock->l_pid);
1857         if (lock->l_conn_export != NULL)
1858                 obd = lock->l_conn_export->exp_obd;
1859         if (lock->l_export && lock->l_export->exp_connection) {
1860                 CDEBUG(level, "  Node: NID %s (rhandle: "LPX64")\n",
1861                      libcfs_nid2str(lock->l_export->exp_connection->c_peer.nid),
1862                      lock->l_remote_handle.cookie);
1863         } else if (obd == NULL) {
1864                 CDEBUG(level, "  Node: local\n");
1865         } else {
1866                 struct obd_import *imp = obd->u.cli.cl_import;
1867                 CDEBUG(level, "  Node: NID %s (rhandle: "LPX64")\n",
1868                        libcfs_nid2str(imp->imp_connection->c_peer.nid),
1869                        lock->l_remote_handle.cookie);
1870         }
1871         CDEBUG(level, "  Resource: %p ("LPU64"/"LPU64"/"LPU64")\n",
1872                   lock->l_resource,
1873                   lock->l_resource->lr_name.name[0],
1874                   lock->l_resource->lr_name.name[1],
1875                   lock->l_resource->lr_name.name[2]);
1876         CDEBUG(level, "  Req mode: %s, grant mode: %s, rc: %u, read: %d, "
1877                "write: %d flags: "LPX64"\n", ldlm_lockname[lock->l_req_mode],
1878                ldlm_lockname[lock->l_granted_mode],
1879                cfs_atomic_read(&lock->l_refc), lock->l_readers, lock->l_writers,
1880                lock->l_flags);
1881         if (lock->l_resource->lr_type == LDLM_EXTENT)
1882                 CDEBUG(level, "  Extent: "LPU64" -> "LPU64
1883                        " (req "LPU64"-"LPU64")\n",
1884                        lock->l_policy_data.l_extent.start,
1885                        lock->l_policy_data.l_extent.end,
1886                        lock->l_req_extent.start, lock->l_req_extent.end);
1887         else if (lock->l_resource->lr_type == LDLM_FLOCK)
1888                 CDEBUG(level, "  Pid: %d Extent: "LPU64" -> "LPU64"\n",
1889                        lock->l_policy_data.l_flock.pid,
1890                        lock->l_policy_data.l_flock.start,
1891                        lock->l_policy_data.l_flock.end);
1892        else if (lock->l_resource->lr_type == LDLM_IBITS)
1893                 CDEBUG(level, "  Bits: "LPX64"\n",
1894                        lock->l_policy_data.l_inodebits.bits);
1895 }
1896
1897 void ldlm_lock_dump_handle(int level, struct lustre_handle *lockh)
1898 {
1899         struct ldlm_lock *lock;
1900
1901         if (!((libcfs_debug | D_ERROR) & level))
1902                 return;
1903
1904         lock = ldlm_handle2lock(lockh);
1905         if (lock == NULL)
1906                 return;
1907
1908         ldlm_lock_dump(D_OTHER, lock, 0);
1909
1910         LDLM_LOCK_PUT(lock);
1911 }
1912
1913 void _ldlm_lock_debug(struct ldlm_lock *lock, __u32 level,
1914                       struct libcfs_debug_msg_data *data, const char *fmt,
1915                       ...)
1916 {
1917         va_list args;
1918         cfs_debug_limit_state_t *cdls = data->msg_cdls;
1919
1920         va_start(args, fmt);
1921
1922         if (lock->l_resource == NULL) {
1923                 libcfs_debug_vmsg2(cdls, data->msg_subsys, level,data->msg_file,
1924                                    data->msg_fn, data->msg_line, fmt, args,
1925                        " ns: \?\? lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
1926                        "res: \?\? rrc=\?\? type: \?\?\? flags: "LPX64" remote: "
1927                        LPX64" expref: %d pid: %u timeout: %lu\n", lock,
1928                        lock->l_handle.h_cookie, cfs_atomic_read(&lock->l_refc),
1929                        lock->l_readers, lock->l_writers,
1930                        ldlm_lockname[lock->l_granted_mode],
1931                        ldlm_lockname[lock->l_req_mode],
1932                        lock->l_flags, lock->l_remote_handle.cookie,
1933                        lock->l_export ?
1934                        cfs_atomic_read(&lock->l_export->exp_refcount) : -99,
1935                        lock->l_pid, lock->l_callback_timeout);
1936                 va_end(args);
1937                 return;
1938         }
1939
1940         switch (lock->l_resource->lr_type) {
1941         case LDLM_EXTENT:
1942                 libcfs_debug_vmsg2(cdls, data->msg_subsys, level,data->msg_file,
1943                                    data->msg_fn, data->msg_line, fmt, args,
1944                        " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
1945                        "res: "LPU64"/"LPU64" rrc: %d type: %s ["LPU64"->"LPU64
1946                        "] (req "LPU64"->"LPU64") flags: "LPX64" remote: "LPX64
1947                        " expref: %d pid: %u timeout %lu\n",
1948                        ldlm_lock_to_ns_name(lock), lock,
1949                        lock->l_handle.h_cookie, cfs_atomic_read(&lock->l_refc),
1950                        lock->l_readers, lock->l_writers,
1951                        ldlm_lockname[lock->l_granted_mode],
1952                        ldlm_lockname[lock->l_req_mode],
1953                        lock->l_resource->lr_name.name[0],
1954                        lock->l_resource->lr_name.name[1],
1955                        cfs_atomic_read(&lock->l_resource->lr_refcount),
1956                        ldlm_typename[lock->l_resource->lr_type],
1957                        lock->l_policy_data.l_extent.start,
1958                        lock->l_policy_data.l_extent.end,
1959                        lock->l_req_extent.start, lock->l_req_extent.end,
1960                        lock->l_flags, lock->l_remote_handle.cookie,
1961                        lock->l_export ?
1962                        cfs_atomic_read(&lock->l_export->exp_refcount) : -99,
1963                        lock->l_pid, lock->l_callback_timeout);
1964                 break;
1965
1966         case LDLM_FLOCK:
1967                 libcfs_debug_vmsg2(cdls, data->msg_subsys, level,data->msg_file,
1968                                    data->msg_fn, data->msg_line, fmt, args,
1969                        " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
1970                        "res: "LPU64"/"LPU64" rrc: %d type: %s pid: %d "
1971                        "["LPU64"->"LPU64"] flags: "LPX64" remote: "LPX64
1972                        " expref: %d pid: %u timeout: %lu\n",
1973                        ldlm_lock_to_ns_name(lock), lock,
1974                        lock->l_handle.h_cookie, cfs_atomic_read(&lock->l_refc),
1975                        lock->l_readers, lock->l_writers,
1976                        ldlm_lockname[lock->l_granted_mode],
1977                        ldlm_lockname[lock->l_req_mode],
1978                        lock->l_resource->lr_name.name[0],
1979                        lock->l_resource->lr_name.name[1],
1980                        cfs_atomic_read(&lock->l_resource->lr_refcount),
1981                        ldlm_typename[lock->l_resource->lr_type],
1982                        lock->l_policy_data.l_flock.pid,
1983                        lock->l_policy_data.l_flock.start,
1984                        lock->l_policy_data.l_flock.end,
1985                        lock->l_flags, lock->l_remote_handle.cookie,
1986                        lock->l_export ?
1987                        cfs_atomic_read(&lock->l_export->exp_refcount) : -99,
1988                        lock->l_pid, lock->l_callback_timeout);
1989                 break;
1990
1991         case LDLM_IBITS:
1992                 libcfs_debug_vmsg2(cdls, data->msg_subsys, level,data->msg_file,
1993                                    data->msg_fn, data->msg_line, fmt, args,
1994                        " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
1995                        "res: "LPU64"/"LPU64" bits "LPX64" rrc: %d type: %s "
1996                        "flags: "LPX64" remote: "LPX64" expref: %d "
1997                        "pid: %u timeout: %lu\n",
1998                        ldlm_lock_to_ns_name(lock),
1999                        lock, lock->l_handle.h_cookie,
2000                        cfs_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                        lock->l_policy_data.l_inodebits.bits,
2007                        cfs_atomic_read(&lock->l_resource->lr_refcount),
2008                        ldlm_typename[lock->l_resource->lr_type],
2009                        lock->l_flags, lock->l_remote_handle.cookie,
2010                        lock->l_export ?
2011                        cfs_atomic_read(&lock->l_export->exp_refcount) : -99,
2012                        lock->l_pid, lock->l_callback_timeout);
2013                 break;
2014
2015         default:
2016                 libcfs_debug_vmsg2(cdls, data->msg_subsys, level,data->msg_file,
2017                                    data->msg_fn, data->msg_line, fmt, args,
2018                        " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
2019                        "res: "LPU64"/"LPU64" rrc: %d type: %s flags: "LPX64" "
2020                        "remote: "LPX64" expref: %d pid: %u timeout %lu\n",
2021                        ldlm_lock_to_ns_name(lock),
2022                        lock, lock->l_handle.h_cookie,
2023                        cfs_atomic_read (&lock->l_refc),
2024                        lock->l_readers, lock->l_writers,
2025                        ldlm_lockname[lock->l_granted_mode],
2026                        ldlm_lockname[lock->l_req_mode],
2027                        lock->l_resource->lr_name.name[0],
2028                        lock->l_resource->lr_name.name[1],
2029                        cfs_atomic_read(&lock->l_resource->lr_refcount),
2030                        ldlm_typename[lock->l_resource->lr_type],
2031                        lock->l_flags, lock->l_remote_handle.cookie,
2032                        lock->l_export ?
2033                        cfs_atomic_read(&lock->l_export->exp_refcount) : -99,
2034                        lock->l_pid, lock->l_callback_timeout);
2035                 break;
2036         }
2037         va_end(args);
2038 }
2039 EXPORT_SYMBOL(_ldlm_lock_debug);