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  * Copyright (c) 2011, 2012, Whamcloud, Inc.
  33  */
  34 /*
  35  * This file is part of Lustre, http://www.lustre.org/
  36  * Lustre is a trademark of Sun Microsystems, Inc.
  37  *
  38  * lustre/ldlm/ldlm_lock.c
  39  *
  40  * Author: Peter Braam <braam@clusterfs.com>
  41  * Author: Phil Schwan <phil@clusterfs.com>
  42  */
  43
  44 #define DEBUG_SUBSYSTEM S_LDLM
  45
  46 #ifdef __KERNEL__
  47 # include <libcfs/libcfs.h>
  48 # include <linux/lustre_intent.h>
  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 static ldlm_policy_wire_to_local_t ldlm_policy_wire18_to_local[] = {
  77         [LDLM_PLAIN - LDLM_MIN_TYPE] ldlm_plain_policy_wire_to_local,
  78         [LDLM_EXTENT - LDLM_MIN_TYPE] ldlm_extent_policy_wire_to_local,
  79         [LDLM_FLOCK - LDLM_MIN_TYPE] ldlm_flock_policy_wire18_to_local,
  80         [LDLM_IBITS - LDLM_MIN_TYPE] ldlm_ibits_policy_wire_to_local,
  81 };
  82
  83 static ldlm_policy_wire_to_local_t ldlm_policy_wire21_to_local[] = {
  84         [LDLM_PLAIN - LDLM_MIN_TYPE] ldlm_plain_policy_wire_to_local,
  85         [LDLM_EXTENT - LDLM_MIN_TYPE] ldlm_extent_policy_wire_to_local,
  86         [LDLM_FLOCK - LDLM_MIN_TYPE] ldlm_flock_policy_wire21_to_local,
  87         [LDLM_IBITS - LDLM_MIN_TYPE] ldlm_ibits_policy_wire_to_local,
  88 };
  89
  90 static ldlm_policy_local_to_wire_t ldlm_policy_local_to_wire[] = {
  91         [LDLM_PLAIN - LDLM_MIN_TYPE] ldlm_plain_policy_local_to_wire,
  92         [LDLM_EXTENT - LDLM_MIN_TYPE] ldlm_extent_policy_local_to_wire,
  93         [LDLM_FLOCK - LDLM_MIN_TYPE] ldlm_flock_policy_local_to_wire,
  94         [LDLM_IBITS - LDLM_MIN_TYPE] ldlm_ibits_policy_local_to_wire,
  95 };
  96
  97 /**
  98  * Converts lock policy from local format to on the wire lock_desc format
  99  */
 100 void ldlm_convert_policy_to_wire(ldlm_type_t type,
 101                                  const ldlm_policy_data_t *lpolicy,
 102                                  ldlm_wire_policy_data_t *wpolicy)
 103 {
 104         ldlm_policy_local_to_wire_t convert;
 105
 106         convert = ldlm_policy_local_to_wire[type - LDLM_MIN_TYPE];
 107
 108         convert(lpolicy, wpolicy);
 109 }
 110
 111 /**
 112  * Converts lock policy from on the wire lock_desc format to local format
 113  */
 114 void ldlm_convert_policy_to_local(struct obd_export *exp, ldlm_type_t type,
 115                                   const ldlm_wire_policy_data_t *wpolicy,
 116                                   ldlm_policy_data_t *lpolicy)
 117 {
 118         ldlm_policy_wire_to_local_t convert;
 119         int new_client;
 120
 121         /** some badnes for 2.0.0 clients, but 2.0.0 isn't supported */
 122         new_client = (exp->exp_connect_flags & OBD_CONNECT_FULL20) != 0;
 123         if (new_client)
 124                convert = ldlm_policy_wire21_to_local[type - LDLM_MIN_TYPE];
 125         else
 126                convert = ldlm_policy_wire18_to_local[type - LDLM_MIN_TYPE];
 127
 128         convert(wpolicy, lpolicy);
 129 }
 130
 131 char *ldlm_it2str(int it)
 132 {
 133         switch (it) {
 134         case IT_OPEN:
 135                 return "open";
 136         case IT_CREAT:
 137                 return "creat";
 138         case (IT_OPEN | IT_CREAT):
 139                 return "open|creat";
 140         case IT_READDIR:
 141                 return "readdir";
 142         case IT_GETATTR:
 143                 return "getattr";
 144         case IT_LOOKUP:
 145                 return "lookup";
 146         case IT_UNLINK:
 147                 return "unlink";
 148         case IT_GETXATTR:
 149                 return "getxattr";
 150         case IT_LAYOUT:
 151                 return "layout";
 152         default:
 153                 CERROR("Unknown intent %d\n", it);
 154                 return "UNKNOWN";
 155         }
 156 }
 157
 158 extern cfs_mem_cache_t *ldlm_lock_slab;
 159
 160 #ifdef HAVE_SERVER_SUPPORT
 161 static ldlm_processing_policy ldlm_processing_policy_table[] = {
 162         [LDLM_PLAIN] ldlm_process_plain_lock,
 163         [LDLM_EXTENT] ldlm_process_extent_lock,
 164 # ifdef __KERNEL__
 165         [LDLM_FLOCK] ldlm_process_flock_lock,
 166 # endif
 167         [LDLM_IBITS] ldlm_process_inodebits_lock,
 168 };
 169
 170 ldlm_processing_policy ldlm_get_processing_policy(struct ldlm_resource *res)
 171 {
 172         return ldlm_processing_policy_table[res->lr_type];
 173 }
 174 #endif /* HAVE_SERVER_SUPPORT */
 175
 176 void ldlm_register_intent(struct ldlm_namespace *ns, ldlm_res_policy arg)
 177 {
 178         ns->ns_policy = arg;
 179 }
 180
 181 /*
 182  * REFCOUNTED LOCK OBJECTS
 183  */
 184
 185
 186 /*
 187  * Lock refcounts, during creation:
 188  *   - one special one for allocation, dec'd only once in destroy
 189  *   - one for being a lock that's in-use
 190  *   - one for the addref associated with a new lock
 191  */
 192 struct ldlm_lock *ldlm_lock_get(struct ldlm_lock *lock)
 193 {
 194         cfs_atomic_inc(&lock->l_refc);
 195         return lock;
 196 }
 197
 198 static void ldlm_lock_free(struct ldlm_lock *lock, size_t size)
 199 {
 200         LASSERT(size == sizeof(*lock));
 201         OBD_SLAB_FREE(lock, ldlm_lock_slab, sizeof(*lock));
 202 }
 203
 204 void ldlm_lock_put(struct ldlm_lock *lock)
 205 {
 206         ENTRY;
 207
 208         LASSERT(lock->l_resource != LP_POISON);
 209         LASSERT(cfs_atomic_read(&lock->l_refc) > 0);
 210         if (cfs_atomic_dec_and_test(&lock->l_refc)) {
 211                 struct ldlm_resource *res;
 212
 213                 LDLM_DEBUG(lock,
 214                            "final lock_put on destroyed lock, freeing it.");
 215
 216                 res = lock->l_resource;
 217                 LASSERT(lock->l_destroyed);
 218                 LASSERT(cfs_list_empty(&lock->l_res_link));
 219                 LASSERT(cfs_list_empty(&lock->l_pending_chain));
 220
 221                 lprocfs_counter_decr(ldlm_res_to_ns(res)->ns_stats,
 222                                      LDLM_NSS_LOCKS);
 223                 lu_ref_del(&res->lr_reference, "lock", lock);
 224                 ldlm_resource_putref(res);
 225                 lock->l_resource = NULL;
 226                 if (lock->l_export) {
 227                         class_export_lock_put(lock->l_export, lock);
 228                         lock->l_export = NULL;
 229                 }
 230
 231                 if (lock->l_lvb_data != NULL)
 232                         OBD_FREE(lock->l_lvb_data, lock->l_lvb_len);
 233
 234                 ldlm_interval_free(ldlm_interval_detach(lock));
 235                 lu_ref_fini(&lock->l_reference);
 236                 OBD_FREE_RCU_CB(lock, sizeof(*lock), &lock->l_handle,
 237                                 ldlm_lock_free);
 238         }
 239
 240         EXIT;
 241 }
 242
 243 int ldlm_lock_remove_from_lru_nolock(struct ldlm_lock *lock)
 244 {
 245         int rc = 0;
 246         if (!cfs_list_empty(&lock->l_lru)) {
 247                 struct ldlm_namespace *ns = ldlm_lock_to_ns(lock);
 248
 249                 LASSERT(lock->l_resource->lr_type != LDLM_FLOCK);
 250                 cfs_list_del_init(&lock->l_lru);
 251                 if (lock->l_flags & LDLM_FL_SKIPPED)
 252                         lock->l_flags &= ~LDLM_FL_SKIPPED;
 253                 LASSERT(ns->ns_nr_unused > 0);
 254                 ns->ns_nr_unused--;
 255                 rc = 1;
 256         }
 257         return rc;
 258 }
 259
 260 int ldlm_lock_remove_from_lru(struct ldlm_lock *lock)
 261 {
 262         struct ldlm_namespace *ns = ldlm_lock_to_ns(lock);
 263         int rc;
 264
 265         ENTRY;
 266         if (lock->l_ns_srv) {
 267                 LASSERT(cfs_list_empty(&lock->l_lru));
 268                 RETURN(0);
 269         }
 270
 271         cfs_spin_lock(&ns->ns_lock);
 272         rc = ldlm_lock_remove_from_lru_nolock(lock);
 273         cfs_spin_unlock(&ns->ns_lock);
 274         EXIT;
 275         return rc;
 276 }
 277
 278 void ldlm_lock_add_to_lru_nolock(struct ldlm_lock *lock)
 279 {
 280         struct ldlm_namespace *ns = ldlm_lock_to_ns(lock);
 281
 282         lock->l_last_used = cfs_time_current();
 283         LASSERT(cfs_list_empty(&lock->l_lru));
 284         LASSERT(lock->l_resource->lr_type != LDLM_FLOCK);
 285         cfs_list_add_tail(&lock->l_lru, &ns->ns_unused_list);
 286         LASSERT(ns->ns_nr_unused >= 0);
 287         ns->ns_nr_unused++;
 288 }
 289
 290 void ldlm_lock_add_to_lru(struct ldlm_lock *lock)
 291 {
 292         struct ldlm_namespace *ns = ldlm_lock_to_ns(lock);
 293
 294         ENTRY;
 295         cfs_spin_lock(&ns->ns_lock);
 296         ldlm_lock_add_to_lru_nolock(lock);
 297         cfs_spin_unlock(&ns->ns_lock);
 298         EXIT;
 299 }
 300
 301 void ldlm_lock_touch_in_lru(struct ldlm_lock *lock)
 302 {
 303         struct ldlm_namespace *ns = ldlm_lock_to_ns(lock);
 304
 305         ENTRY;
 306         if (lock->l_ns_srv) {
 307                 LASSERT(cfs_list_empty(&lock->l_lru));
 308                 EXIT;
 309                 return;
 310         }
 311
 312         cfs_spin_lock(&ns->ns_lock);
 313         if (!cfs_list_empty(&lock->l_lru)) {
 314                 ldlm_lock_remove_from_lru_nolock(lock);
 315                 ldlm_lock_add_to_lru_nolock(lock);
 316         }
 317         cfs_spin_unlock(&ns->ns_lock);
 318         EXIT;
 319 }
 320
 321 /* This used to have a 'strict' flag, which recovery would use to mark an
 322  * in-use lock as needing-to-die.  Lest I am ever tempted to put it back, I
 323  * shall explain why it's gone: with the new hash table scheme, once you call
 324  * ldlm_lock_destroy, you can never drop your final references on this lock.
 325  * Because it's not in the hash table anymore.  -phil */
 326 int ldlm_lock_destroy_internal(struct ldlm_lock *lock)
 327 {
 328         ENTRY;
 329
 330         if (lock->l_readers || lock->l_writers) {
 331                 LDLM_ERROR(lock, "lock still has references");
 332                 ldlm_lock_dump(D_ERROR, lock, 0);
 333                 LBUG();
 334         }
 335
 336         if (!cfs_list_empty(&lock->l_res_link)) {
 337                 LDLM_ERROR(lock, "lock still on resource");
 338                 ldlm_lock_dump(D_ERROR, lock, 0);
 339                 LBUG();
 340         }
 341
 342         if (lock->l_destroyed) {
 343                 LASSERT(cfs_list_empty(&lock->l_lru));
 344                 EXIT;
 345                 return 0;
 346         }
 347         lock->l_destroyed = 1;
 348
 349         if (lock->l_export && lock->l_export->exp_lock_hash &&
 350             !cfs_hlist_unhashed(&lock->l_exp_hash))
 351                 cfs_hash_del(lock->l_export->exp_lock_hash,
 352                              &lock->l_remote_handle, &lock->l_exp_hash);
 353
 354         ldlm_lock_remove_from_lru(lock);
 355         class_handle_unhash(&lock->l_handle);
 356
 357 #if 0
 358         /* Wake anyone waiting for this lock */
 359         /* FIXME: I should probably add yet another flag, instead of using
 360          * l_export to only call this on clients */
 361         if (lock->l_export)
 362                 class_export_put(lock->l_export);
 363         lock->l_export = NULL;
 364         if (lock->l_export && lock->l_completion_ast)
 365                 lock->l_completion_ast(lock, 0);
 366 #endif
 367         EXIT;
 368         return 1;
 369 }
 370
 371 void ldlm_lock_destroy(struct ldlm_lock *lock)
 372 {
 373         int first;
 374         ENTRY;
 375         lock_res_and_lock(lock);
 376         first = ldlm_lock_destroy_internal(lock);
 377         unlock_res_and_lock(lock);
 378
 379         /* drop reference from hashtable only for first destroy */
 380         if (first) {
 381                 lu_ref_del(&lock->l_reference, "hash", lock);
 382                 LDLM_LOCK_RELEASE(lock);
 383         }
 384         EXIT;
 385 }
 386
 387 void ldlm_lock_destroy_nolock(struct ldlm_lock *lock)
 388 {
 389         int first;
 390         ENTRY;
 391         first = ldlm_lock_destroy_internal(lock);
 392         /* drop reference from hashtable only for first destroy */
 393         if (first) {
 394                 lu_ref_del(&lock->l_reference, "hash", lock);
 395                 LDLM_LOCK_RELEASE(lock);
 396         }
 397         EXIT;
 398 }
 399
 400 /* this is called by portals_handle2object with the handle lock taken */
 401 static void lock_handle_addref(void *lock)
 402 {
 403         LDLM_LOCK_GET((struct ldlm_lock *)lock);
 404 }
 405
 406 /*
 407  * usage: pass in a resource on which you have done ldlm_resource_get
 408  *        new lock will take over the refcount.
 409  * returns: lock with refcount 2 - one for current caller and one for remote
 410  */
 411 static struct ldlm_lock *ldlm_lock_new(struct ldlm_resource *resource)
 412 {
 413         struct ldlm_lock *lock;
 414         ENTRY;
 415
 416         if (resource == NULL)
 417                 LBUG();
 418
 419         OBD_SLAB_ALLOC_PTR_GFP(lock, ldlm_lock_slab, CFS_ALLOC_IO);
 420         if (lock == NULL)
 421                 RETURN(NULL);
 422
 423         cfs_spin_lock_init(&lock->l_lock);
 424         lock->l_resource = resource;
 425         lu_ref_add(&resource->lr_reference, "lock", lock);
 426
 427         cfs_atomic_set(&lock->l_refc, 2);
 428         CFS_INIT_LIST_HEAD(&lock->l_res_link);
 429         CFS_INIT_LIST_HEAD(&lock->l_lru);
 430         CFS_INIT_LIST_HEAD(&lock->l_pending_chain);
 431         CFS_INIT_LIST_HEAD(&lock->l_bl_ast);
 432         CFS_INIT_LIST_HEAD(&lock->l_cp_ast);
 433         CFS_INIT_LIST_HEAD(&lock->l_rk_ast);
 434         cfs_waitq_init(&lock->l_waitq);
 435         lock->l_blocking_lock = NULL;
 436         CFS_INIT_LIST_HEAD(&lock->l_sl_mode);
 437         CFS_INIT_LIST_HEAD(&lock->l_sl_policy);
 438         CFS_INIT_HLIST_NODE(&lock->l_exp_hash);
 439
 440         lprocfs_counter_incr(ldlm_res_to_ns(resource)->ns_stats,
 441                              LDLM_NSS_LOCKS);
 442         CFS_INIT_LIST_HEAD(&lock->l_handle.h_link);
 443         class_handle_hash(&lock->l_handle, lock_handle_addref);
 444
 445         lu_ref_init(&lock->l_reference);
 446         lu_ref_add(&lock->l_reference, "hash", lock);
 447         lock->l_callback_timeout = 0;
 448
 449 #if LUSTRE_TRACKS_LOCK_EXP_REFS
 450         CFS_INIT_LIST_HEAD(&lock->l_exp_refs_link);
 451         lock->l_exp_refs_nr = 0;
 452         lock->l_exp_refs_target = NULL;
 453 #endif
 454         CFS_INIT_LIST_HEAD(&lock->l_exp_list);
 455
 456         RETURN(lock);
 457 }
 458
 459 int ldlm_lock_change_resource(struct ldlm_namespace *ns, struct ldlm_lock *lock,
 460                               const struct ldlm_res_id *new_resid)
 461 {
 462         struct ldlm_resource *oldres = lock->l_resource;
 463         struct ldlm_resource *newres;
 464         int type;
 465         ENTRY;
 466
 467         LASSERT(ns_is_client(ns));
 468
 469         lock_res_and_lock(lock);
 470         if (memcmp(new_resid, &lock->l_resource->lr_name,
 471                    sizeof(lock->l_resource->lr_name)) == 0) {
 472                 /* Nothing to do */
 473                 unlock_res_and_lock(lock);
 474                 RETURN(0);
 475         }
 476
 477         LASSERT(new_resid->name[0] != 0);
 478
 479         /* This function assumes that the lock isn't on any lists */
 480         LASSERT(cfs_list_empty(&lock->l_res_link));
 481
 482         type = oldres->lr_type;
 483         unlock_res_and_lock(lock);
 484
 485         newres = ldlm_resource_get(ns, NULL, new_resid, type, 1);
 486         if (newres == NULL)
 487                 RETURN(-ENOMEM);
 488
 489         lu_ref_add(&newres->lr_reference, "lock", lock);
 490         /*
 491          * To flip the lock from the old to the new resource, lock, oldres and
 492          * newres have to be locked. Resource spin-locks are nested within
 493          * lock->l_lock, and are taken in the memory address order to avoid
 494          * dead-locks.
 495          */
 496         cfs_spin_lock(&lock->l_lock);
 497         oldres = lock->l_resource;
 498         if (oldres < newres) {
 499                 lock_res(oldres);
 500                 lock_res_nested(newres, LRT_NEW);
 501         } else {
 502                 lock_res(newres);
 503                 lock_res_nested(oldres, LRT_NEW);
 504         }
 505         LASSERT(memcmp(new_resid, &oldres->lr_name,
 506                        sizeof oldres->lr_name) != 0);
 507         lock->l_resource = newres;
 508         unlock_res(oldres);
 509         unlock_res_and_lock(lock);
 510
 511         /* ...and the flowers are still standing! */
 512         lu_ref_del(&oldres->lr_reference, "lock", lock);
 513         ldlm_resource_putref(oldres);
 514
 515         RETURN(0);
 516 }
 517
 518 /*
 519  *  HANDLES
 520  */
 521
 522 void ldlm_lock2handle(const struct ldlm_lock *lock, struct lustre_handle *lockh)
 523 {
 524         lockh->cookie = lock->l_handle.h_cookie;
 525 }
 526
 527 /* if flags: atomically get the lock and set the flags.
 528  *           Return NULL if flag already set
 529  */
 530
 531 struct ldlm_lock *__ldlm_handle2lock(const struct lustre_handle *handle,
 532                                      int flags)
 533 {
 534         struct ldlm_lock *lock;
 535         ENTRY;
 536
 537         LASSERT(handle);
 538
 539         lock = class_handle2object(handle->cookie);
 540         if (lock == NULL)
 541                 RETURN(NULL);
 542
 543         /* It's unlikely but possible that someone marked the lock as
 544          * destroyed after we did handle2object on it */
 545         if (flags == 0 && !lock->l_destroyed) {
 546                 lu_ref_add(&lock->l_reference, "handle", cfs_current());
 547                 RETURN(lock);
 548         }
 549
 550         lock_res_and_lock(lock);
 551
 552         LASSERT(lock->l_resource != NULL);
 553
 554         lu_ref_add_atomic(&lock->l_reference, "handle", cfs_current());
 555         if (unlikely(lock->l_destroyed)) {
 556                 unlock_res_and_lock(lock);
 557                 CDEBUG(D_INFO, "lock already destroyed: lock %p\n", lock);
 558                 LDLM_LOCK_PUT(lock);
 559                 RETURN(NULL);
 560         }
 561
 562         if (flags && (lock->l_flags & flags)) {
 563                 unlock_res_and_lock(lock);
 564                 LDLM_LOCK_PUT(lock);
 565                 RETURN(NULL);
 566         }
 567
 568         if (flags)
 569                 lock->l_flags |= flags;
 570
 571         unlock_res_and_lock(lock);
 572         RETURN(lock);
 573 }
 574
 575 void ldlm_lock2desc(struct ldlm_lock *lock, struct ldlm_lock_desc *desc)
 576 {
 577         struct obd_export *exp = lock->l_export?:lock->l_conn_export;
 578         /* INODEBITS_INTEROP: If the other side does not support
 579          * inodebits, reply with a plain lock descriptor.
 580          */
 581         if ((lock->l_resource->lr_type == LDLM_IBITS) &&
 582             (exp && !(exp->exp_connect_flags & OBD_CONNECT_IBITS))) {
 583                 /* Make sure all the right bits are set in this lock we
 584                    are going to pass to client */
 585                 LASSERTF(lock->l_policy_data.l_inodebits.bits ==
 586                          (MDS_INODELOCK_LOOKUP | MDS_INODELOCK_UPDATE |
 587                           MDS_INODELOCK_LAYOUT),
 588                          "Inappropriate inode lock bits during "
 589                          "conversion " LPU64 "\n",
 590                          lock->l_policy_data.l_inodebits.bits);
 591
 592                 ldlm_res2desc(lock->l_resource, &desc->l_resource);
 593                 desc->l_resource.lr_type = LDLM_PLAIN;
 594
 595                 /* Convert "new" lock mode to something old client can
 596                    understand */
 597                 if ((lock->l_req_mode == LCK_CR) ||
 598                     (lock->l_req_mode == LCK_CW))
 599                         desc->l_req_mode = LCK_PR;
 600                 else
 601                         desc->l_req_mode = lock->l_req_mode;
 602                 if ((lock->l_granted_mode == LCK_CR) ||
 603                     (lock->l_granted_mode == LCK_CW)) {
 604                         desc->l_granted_mode = LCK_PR;
 605                 } else {
 606                         /* We never grant PW/EX locks to clients */
 607                         LASSERT((lock->l_granted_mode != LCK_PW) &&
 608                                 (lock->l_granted_mode != LCK_EX));
 609                         desc->l_granted_mode = lock->l_granted_mode;
 610                 }
 611
 612                 /* We do not copy policy here, because there is no
 613                    policy for plain locks */
 614         } else {
 615                 ldlm_res2desc(lock->l_resource, &desc->l_resource);
 616                 desc->l_req_mode = lock->l_req_mode;
 617                 desc->l_granted_mode = lock->l_granted_mode;
 618                 ldlm_convert_policy_to_wire(lock->l_resource->lr_type,
 619                                             &lock->l_policy_data,
 620                                             &desc->l_policy_data);
 621         }
 622 }
 623
 624 void ldlm_add_bl_work_item(struct ldlm_lock *lock, struct ldlm_lock *new,
 625                            cfs_list_t *work_list)
 626 {
 627         if ((lock->l_flags & LDLM_FL_AST_SENT) == 0) {
 628                 LDLM_DEBUG(lock, "lock incompatible; sending blocking AST.");
 629                 lock->l_flags |= LDLM_FL_AST_SENT;
 630                 /* If the enqueuing client said so, tell the AST recipient to
 631                  * discard dirty data, rather than writing back. */
 632                 if (new->l_flags & LDLM_AST_DISCARD_DATA)
 633                         lock->l_flags |= LDLM_FL_DISCARD_DATA;
 634                 LASSERT(cfs_list_empty(&lock->l_bl_ast));
 635                 cfs_list_add(&lock->l_bl_ast, work_list);
 636                 LDLM_LOCK_GET(lock);
 637                 LASSERT(lock->l_blocking_lock == NULL);
 638                 lock->l_blocking_lock = LDLM_LOCK_GET(new);
 639         }
 640 }
 641
 642 void ldlm_add_cp_work_item(struct ldlm_lock *lock, cfs_list_t *work_list)
 643 {
 644         if ((lock->l_flags & LDLM_FL_CP_REQD) == 0) {
 645                 lock->l_flags |= LDLM_FL_CP_REQD;
 646                 LDLM_DEBUG(lock, "lock granted; sending completion AST.");
 647                 LASSERT(cfs_list_empty(&lock->l_cp_ast));
 648                 cfs_list_add(&lock->l_cp_ast, work_list);
 649                 LDLM_LOCK_GET(lock);
 650         }
 651 }
 652
 653 /* must be called with lr_lock held */
 654 void ldlm_add_ast_work_item(struct ldlm_lock *lock, struct ldlm_lock *new,
 655                             cfs_list_t *work_list)
 656 {
 657         ENTRY;
 658         check_res_locked(lock->l_resource);
 659         if (new)
 660                 ldlm_add_bl_work_item(lock, new, work_list);
 661         else
 662                 ldlm_add_cp_work_item(lock, work_list);
 663         EXIT;
 664 }
 665
 666 void ldlm_lock_addref(struct lustre_handle *lockh, __u32 mode)
 667 {
 668         struct ldlm_lock *lock;
 669
 670         lock = ldlm_handle2lock(lockh);
 671         LASSERT(lock != NULL);
 672         ldlm_lock_addref_internal(lock, mode);
 673         LDLM_LOCK_PUT(lock);
 674 }
 675
 676 void ldlm_lock_addref_internal_nolock(struct ldlm_lock *lock, __u32 mode)
 677 {
 678         ldlm_lock_remove_from_lru(lock);
 679         if (mode & (LCK_NL | LCK_CR | LCK_PR)) {
 680                 lock->l_readers++;
 681                 lu_ref_add_atomic(&lock->l_reference, "reader", lock);
 682         }
 683         if (mode & (LCK_EX | LCK_CW | LCK_PW | LCK_GROUP | LCK_COS)) {
 684                 lock->l_writers++;
 685                 lu_ref_add_atomic(&lock->l_reference, "writer", lock);
 686         }
 687         LDLM_LOCK_GET(lock);
 688         lu_ref_add_atomic(&lock->l_reference, "user", lock);
 689         LDLM_DEBUG(lock, "ldlm_lock_addref(%s)", ldlm_lockname[mode]);
 690 }
 691
 692 /**
 693  * Attempts to addref a lock, and fails if lock is already LDLM_FL_CBPENDING
 694  * or destroyed.
 695  *
 696  * \retval 0 success, lock was addref-ed
 697  *
 698  * \retval -EAGAIN lock is being canceled.
 699  */
 700 int ldlm_lock_addref_try(struct lustre_handle *lockh, __u32 mode)
 701 {
 702         struct ldlm_lock *lock;
 703         int               result;
 704
 705         result = -EAGAIN;
 706         lock = ldlm_handle2lock(lockh);
 707         if (lock != NULL) {
 708                 lock_res_and_lock(lock);
 709                 if (lock->l_readers != 0 || lock->l_writers != 0 ||
 710                     !(lock->l_flags & LDLM_FL_CBPENDING)) {
 711                         ldlm_lock_addref_internal_nolock(lock, mode);
 712                         result = 0;
 713                 }
 714                 unlock_res_and_lock(lock);
 715                 LDLM_LOCK_PUT(lock);
 716         }
 717         return result;
 718 }
 719
 720 /* only called for local locks */
 721 void ldlm_lock_addref_internal(struct ldlm_lock *lock, __u32 mode)
 722 {
 723         lock_res_and_lock(lock);
 724         ldlm_lock_addref_internal_nolock(lock, mode);
 725         unlock_res_and_lock(lock);
 726 }
 727
 728 /* only called in ldlm_flock_destroy and for local locks.
 729  *  * for LDLM_FLOCK type locks, l_blocking_ast is null, and
 730  *   * ldlm_lock_remove_from_lru() does nothing, it is safe
 731  *    * for ldlm_flock_destroy usage by dropping some code */
 732 void ldlm_lock_decref_internal_nolock(struct ldlm_lock *lock, __u32 mode)
 733 {
 734         LDLM_DEBUG(lock, "ldlm_lock_decref(%s)", ldlm_lockname[mode]);
 735         if (mode & (LCK_NL | LCK_CR | LCK_PR)) {
 736                 LASSERT(lock->l_readers > 0);
 737                 lu_ref_del(&lock->l_reference, "reader", lock);
 738                 lock->l_readers--;
 739         }
 740         if (mode & (LCK_EX | LCK_CW | LCK_PW | LCK_GROUP | LCK_COS)) {
 741                 LASSERT(lock->l_writers > 0);
 742                 lu_ref_del(&lock->l_reference, "writer", lock);
 743                 lock->l_writers--;
 744         }
 745
 746         lu_ref_del(&lock->l_reference, "user", lock);
 747         LDLM_LOCK_RELEASE(lock);    /* matches the LDLM_LOCK_GET() in addref */
 748 }
 749
 750 void ldlm_lock_decref_internal(struct ldlm_lock *lock, __u32 mode)
 751 {
 752         struct ldlm_namespace *ns;
 753         ENTRY;
 754
 755         lock_res_and_lock(lock);
 756
 757         ns = ldlm_lock_to_ns(lock);
 758
 759         ldlm_lock_decref_internal_nolock(lock, mode);
 760
 761         if (lock->l_flags & LDLM_FL_LOCAL &&
 762             !lock->l_readers && !lock->l_writers) {
 763                 /* If this is a local lock on a server namespace and this was
 764                  * the last reference, cancel the lock. */
 765                 CDEBUG(D_INFO, "forcing cancel of local lock\n");
 766                 lock->l_flags |= LDLM_FL_CBPENDING;
 767         }
 768
 769         if (!lock->l_readers && !lock->l_writers &&
 770             (lock->l_flags & LDLM_FL_CBPENDING)) {
 771                 /* If we received a blocked AST and this was the last reference,
 772                  * run the callback. */
 773                 if (lock->l_ns_srv && lock->l_export)
 774                         CERROR("FL_CBPENDING set on non-local lock--just a "
 775                                "warning\n");
 776
 777                 LDLM_DEBUG(lock, "final decref done on cbpending lock");
 778
 779                 LDLM_LOCK_GET(lock); /* dropped by bl thread */
 780                 ldlm_lock_remove_from_lru(lock);
 781                 unlock_res_and_lock(lock);
 782
 783                 if (lock->l_flags & LDLM_FL_FAIL_LOC)
 784                         OBD_RACE(OBD_FAIL_LDLM_CP_BL_RACE);
 785
 786                 if ((lock->l_flags & LDLM_FL_ATOMIC_CB) ||
 787                     ldlm_bl_to_thread_lock(ns, NULL, lock) != 0)
 788                         ldlm_handle_bl_callback(ns, NULL, lock);
 789         } else if (ns_is_client(ns) &&
 790                    !lock->l_readers && !lock->l_writers &&
 791                    !(lock->l_flags & LDLM_FL_NO_LRU) &&
 792                    !(lock->l_flags & LDLM_FL_BL_AST)) {
 793
 794                 LDLM_DEBUG(lock, "add lock into lru list");
 795
 796                 /* If this is a client-side namespace and this was the last
 797                  * reference, put it on the LRU. */
 798                 ldlm_lock_add_to_lru(lock);
 799                 unlock_res_and_lock(lock);
 800
 801                 if (lock->l_flags & LDLM_FL_FAIL_LOC)
 802                         OBD_RACE(OBD_FAIL_LDLM_CP_BL_RACE);
 803
 804                 /* Call ldlm_cancel_lru() only if EARLY_CANCEL and LRU RESIZE
 805                  * are not supported by the server, otherwise, it is done on
 806                  * enqueue. */
 807                 if (!exp_connect_cancelset(lock->l_conn_export) &&
 808                     !ns_connect_lru_resize(ns))
 809                         ldlm_cancel_lru(ns, 0, LDLM_ASYNC, 0);
 810         } else {
 811                 LDLM_DEBUG(lock, "do not add lock into lru list");
 812                 unlock_res_and_lock(lock);
 813         }
 814
 815         EXIT;
 816 }
 817
 818 void ldlm_lock_decref(struct lustre_handle *lockh, __u32 mode)
 819 {
 820         struct ldlm_lock *lock = __ldlm_handle2lock(lockh, 0);
 821         LASSERTF(lock != NULL, "Non-existing lock: "LPX64"\n", lockh->cookie);
 822         ldlm_lock_decref_internal(lock, mode);
 823         LDLM_LOCK_PUT(lock);
 824 }
 825
 826 /* This will drop a lock reference and mark it for destruction, but will not
 827  * necessarily cancel the lock before returning. */
 828 void ldlm_lock_decref_and_cancel(struct lustre_handle *lockh, __u32 mode)
 829 {
 830         struct ldlm_lock *lock = __ldlm_handle2lock(lockh, 0);
 831         ENTRY;
 832
 833         LASSERT(lock != NULL);
 834
 835         LDLM_DEBUG(lock, "ldlm_lock_decref(%s)", ldlm_lockname[mode]);
 836         lock_res_and_lock(lock);
 837         lock->l_flags |= LDLM_FL_CBPENDING;
 838         unlock_res_and_lock(lock);
 839         ldlm_lock_decref_internal(lock, mode);
 840         LDLM_LOCK_PUT(lock);
 841 }
 842
 843 struct sl_insert_point {
 844         cfs_list_t *res_link;
 845         cfs_list_t *mode_link;
 846         cfs_list_t *policy_link;
 847 };
 848
 849 /*
 850  * search_granted_lock
 851  *
 852  * Description:
 853  *      Finds a position to insert the new lock.
 854  * Parameters:
 855  *      queue [input]:  the granted list where search acts on;
 856  *      req [input]:    the lock whose position to be located;
 857  *      prev [output]:  positions within 3 lists to insert @req to
 858  * Return Value:
 859  *      filled @prev
 860  * NOTE: called by
 861  *  - ldlm_grant_lock_with_skiplist
 862  */
 863 static void search_granted_lock(cfs_list_t *queue,
 864                                 struct ldlm_lock *req,
 865                                 struct sl_insert_point *prev)
 866 {
 867         cfs_list_t *tmp;
 868         struct ldlm_lock *lock, *mode_end, *policy_end;
 869         ENTRY;
 870
 871         cfs_list_for_each(tmp, queue) {
 872                 lock = cfs_list_entry(tmp, struct ldlm_lock, l_res_link);
 873
 874                 mode_end = cfs_list_entry(lock->l_sl_mode.prev,
 875                                           struct ldlm_lock, l_sl_mode);
 876
 877                 if (lock->l_req_mode != req->l_req_mode) {
 878                         /* jump to last lock of mode group */
 879                         tmp = &mode_end->l_res_link;
 880                         continue;
 881                 }
 882
 883                 /* suitable mode group is found */
 884                 if (lock->l_resource->lr_type == LDLM_PLAIN) {
 885                         /* insert point is last lock of the mode group */
 886                         prev->res_link = &mode_end->l_res_link;
 887                         prev->mode_link = &mode_end->l_sl_mode;
 888                         prev->policy_link = &req->l_sl_policy;
 889                         EXIT;
 890                         return;
 891                 } else if (lock->l_resource->lr_type == LDLM_IBITS) {
 892                         for (;;) {
 893                                 policy_end =
 894                                         cfs_list_entry(lock->l_sl_policy.prev,
 895                                                        struct ldlm_lock,
 896                                                        l_sl_policy);
 897
 898                                 if (lock->l_policy_data.l_inodebits.bits ==
 899                                     req->l_policy_data.l_inodebits.bits) {
 900                                         /* insert point is last lock of
 901                                          * the policy group */
 902                                         prev->res_link =
 903                                                 &policy_end->l_res_link;
 904                                         prev->mode_link =
 905                                                 &policy_end->l_sl_mode;
 906                                         prev->policy_link =
 907                                                 &policy_end->l_sl_policy;
 908                                         EXIT;
 909                                         return;
 910                                 }
 911
 912                                 if (policy_end == mode_end)
 913                                         /* done with mode group */
 914                                         break;
 915
 916                                 /* go to next policy group within mode group */
 917                                 tmp = policy_end->l_res_link.next;
 918                                 lock = cfs_list_entry(tmp, struct ldlm_lock,
 919                                                       l_res_link);
 920                         }  /* loop over policy groups within the mode group */
 921
 922                         /* insert point is last lock of the mode group,
 923                          * new policy group is started */
 924                         prev->res_link = &mode_end->l_res_link;
 925                         prev->mode_link = &mode_end->l_sl_mode;
 926                         prev->policy_link = &req->l_sl_policy;
 927                         EXIT;
 928                         return;
 929                 } else {
 930                         LDLM_ERROR(lock,"is not LDLM_PLAIN or LDLM_IBITS lock");
 931                         LBUG();
 932                 }
 933         }
 934
 935         /* insert point is last lock on the queue,
 936          * new mode group and new policy group are started */
 937         prev->res_link = queue->prev;
 938         prev->mode_link = &req->l_sl_mode;
 939         prev->policy_link = &req->l_sl_policy;
 940         EXIT;
 941         return;
 942 }
 943
 944 static void ldlm_granted_list_add_lock(struct ldlm_lock *lock,
 945                                        struct sl_insert_point *prev)
 946 {
 947         struct ldlm_resource *res = lock->l_resource;
 948         ENTRY;
 949
 950         check_res_locked(res);
 951
 952         ldlm_resource_dump(D_INFO, res);
 953         CDEBUG(D_OTHER, "About to add this lock:\n");
 954         ldlm_lock_dump(D_OTHER, lock, 0);
 955
 956         if (lock->l_destroyed) {
 957                 CDEBUG(D_OTHER, "Lock destroyed, not adding to resource\n");
 958                 return;
 959         }
 960
 961         LASSERT(cfs_list_empty(&lock->l_res_link));
 962         LASSERT(cfs_list_empty(&lock->l_sl_mode));
 963         LASSERT(cfs_list_empty(&lock->l_sl_policy));
 964
 965         cfs_list_add(&lock->l_res_link, prev->res_link);
 966         cfs_list_add(&lock->l_sl_mode, prev->mode_link);
 967         cfs_list_add(&lock->l_sl_policy, prev->policy_link);
 968
 969         EXIT;
 970 }
 971
 972 static void ldlm_grant_lock_with_skiplist(struct ldlm_lock *lock)
 973 {
 974         struct sl_insert_point prev;
 975         ENTRY;
 976
 977         LASSERT(lock->l_req_mode == lock->l_granted_mode);
 978
 979         search_granted_lock(&lock->l_resource->lr_granted, lock, &prev);
 980         ldlm_granted_list_add_lock(lock, &prev);
 981         EXIT;
 982 }
 983
 984 /* NOTE: called by
 985  *  - ldlm_lock_enqueue
 986  *  - ldlm_reprocess_queue
 987  *  - ldlm_lock_convert
 988  *
 989  * must be called with lr_lock held
 990  */
 991 void ldlm_grant_lock(struct ldlm_lock *lock, cfs_list_t *work_list)
 992 {
 993         struct ldlm_resource *res = lock->l_resource;
 994         ENTRY;
 995
 996         check_res_locked(res);
 997
 998         lock->l_granted_mode = lock->l_req_mode;
 999         if (res->lr_type == LDLM_PLAIN || res->lr_type == LDLM_IBITS)
1000                 ldlm_grant_lock_with_skiplist(lock);
1001         else if (res->lr_type == LDLM_EXTENT)
1002                 ldlm_extent_add_lock(res, lock);
1003         else
1004                 ldlm_resource_add_lock(res, &res->lr_granted, lock);
1005
1006         if (lock->l_granted_mode < res->lr_most_restr)
1007                 res->lr_most_restr = lock->l_granted_mode;
1008
1009         if (work_list && lock->l_completion_ast != NULL)
1010                 ldlm_add_ast_work_item(lock, NULL, work_list);
1011
1012         ldlm_pool_add(&ldlm_res_to_ns(res)->ns_pool, lock);
1013         EXIT;
1014 }
1015
1016 /* returns a referenced lock or NULL.  See the flag descriptions below, in the
1017  * comment above ldlm_lock_match */
1018 static struct ldlm_lock *search_queue(cfs_list_t *queue,
1019                                       ldlm_mode_t *mode,
1020                                       ldlm_policy_data_t *policy,
1021                                       struct ldlm_lock *old_lock,
1022                                       int flags, int unref)
1023 {
1024         struct ldlm_lock *lock;
1025         cfs_list_t       *tmp;
1026
1027         cfs_list_for_each(tmp, queue) {
1028                 ldlm_mode_t match;
1029
1030                 lock = cfs_list_entry(tmp, struct ldlm_lock, l_res_link);
1031
1032                 if (lock == old_lock)
1033                         break;
1034
1035                 /* llite sometimes wants to match locks that will be
1036                  * canceled when their users drop, but we allow it to match
1037                  * if it passes in CBPENDING and the lock still has users.
1038                  * this is generally only going to be used by children
1039                  * whose parents already hold a lock so forward progress
1040                  * can still happen. */
1041                 if (lock->l_flags & LDLM_FL_CBPENDING &&
1042                     !(flags & LDLM_FL_CBPENDING))
1043                         continue;
1044                 if (!unref && lock->l_flags & LDLM_FL_CBPENDING &&
1045                     lock->l_readers == 0 && lock->l_writers == 0)
1046                         continue;
1047
1048                 if (!(lock->l_req_mode & *mode))
1049                         continue;
1050                 match = lock->l_req_mode;
1051
1052                 if (lock->l_resource->lr_type == LDLM_EXTENT &&
1053                     (lock->l_policy_data.l_extent.start >
1054                      policy->l_extent.start ||
1055                      lock->l_policy_data.l_extent.end < policy->l_extent.end))
1056                         continue;
1057
1058                 if (unlikely(match == LCK_GROUP) &&
1059                     lock->l_resource->lr_type == LDLM_EXTENT &&
1060                     lock->l_policy_data.l_extent.gid != policy->l_extent.gid)
1061                         continue;
1062
1063                 /* We match if we have existing lock with same or wider set
1064                    of bits. */
1065                 if (lock->l_resource->lr_type == LDLM_IBITS &&
1066                      ((lock->l_policy_data.l_inodebits.bits &
1067                       policy->l_inodebits.bits) !=
1068                       policy->l_inodebits.bits))
1069                         continue;
1070
1071                 if (!unref &&
1072                     (lock->l_destroyed || lock->l_flags & LDLM_FL_FAILED ||
1073                      lock->l_failed))
1074                         continue;
1075
1076                 if ((flags & LDLM_FL_LOCAL_ONLY) &&
1077                     !(lock->l_flags & LDLM_FL_LOCAL))
1078                         continue;
1079
1080                 if (flags & LDLM_FL_TEST_LOCK) {
1081                         LDLM_LOCK_GET(lock);
1082                         ldlm_lock_touch_in_lru(lock);
1083                 } else {
1084                         ldlm_lock_addref_internal_nolock(lock, match);
1085                 }
1086                 *mode = match;
1087                 return lock;
1088         }
1089
1090         return NULL;
1091 }
1092
1093 void ldlm_lock_fail_match_locked(struct ldlm_lock *lock)
1094 {
1095         if (!lock->l_failed) {
1096                 lock->l_failed = 1;
1097                 cfs_waitq_broadcast(&lock->l_waitq);
1098         }
1099 }
1100 EXPORT_SYMBOL(ldlm_lock_fail_match_locked);
1101
1102 void ldlm_lock_fail_match(struct ldlm_lock *lock)
1103 {
1104         lock_res_and_lock(lock);
1105         ldlm_lock_fail_match_locked(lock);
1106         unlock_res_and_lock(lock);
1107 }
1108 EXPORT_SYMBOL(ldlm_lock_fail_match);
1109
1110 void ldlm_lock_allow_match_locked(struct ldlm_lock *lock)
1111 {
1112         lock->l_flags |= LDLM_FL_LVB_READY;
1113         cfs_waitq_broadcast(&lock->l_waitq);
1114 }
1115
1116 void ldlm_lock_allow_match(struct ldlm_lock *lock)
1117 {
1118         lock_res_and_lock(lock);
1119         ldlm_lock_allow_match_locked(lock);
1120         unlock_res_and_lock(lock);
1121 }
1122
1123 /* Can be called in two ways:
1124  *
1125  * If 'ns' is NULL, then lockh describes an existing lock that we want to look
1126  * for a duplicate of.
1127  *
1128  * Otherwise, all of the fields must be filled in, to match against.
1129  *
1130  * If 'flags' contains LDLM_FL_LOCAL_ONLY, then only match local locks on the
1131  *     server (ie, connh is NULL)
1132  * If 'flags' contains LDLM_FL_BLOCK_GRANTED, then only locks on the granted
1133  *     list will be considered
1134  * If 'flags' contains LDLM_FL_CBPENDING, then locks that have been marked
1135  *     to be canceled can still be matched as long as they still have reader
1136  *     or writer refernces
1137  * If 'flags' contains LDLM_FL_TEST_LOCK, then don't actually reference a lock,
1138  *     just tell us if we would have matched.
1139  *
1140  * Returns 1 if it finds an already-existing lock that is compatible; in this
1141  * case, lockh is filled in with a addref()ed lock
1142  *
1143  * we also check security context, if that failed we simply return 0 (to keep
1144  * caller code unchanged), the context failure will be discovered by caller
1145  * sometime later.
1146  */
1147 ldlm_mode_t ldlm_lock_match(struct ldlm_namespace *ns, int flags,
1148                             const struct ldlm_res_id *res_id, ldlm_type_t type,
1149                             ldlm_policy_data_t *policy, ldlm_mode_t mode,
1150                             struct lustre_handle *lockh, int unref)
1151 {
1152         struct ldlm_resource *res;
1153         struct ldlm_lock *lock, *old_lock = NULL;
1154         int rc = 0;
1155         ENTRY;
1156
1157         if (ns == NULL) {
1158                 old_lock = ldlm_handle2lock(lockh);
1159                 LASSERT(old_lock);
1160
1161                 ns = ldlm_lock_to_ns(old_lock);
1162                 res_id = &old_lock->l_resource->lr_name;
1163                 type = old_lock->l_resource->lr_type;
1164                 mode = old_lock->l_req_mode;
1165         }
1166
1167         res = ldlm_resource_get(ns, NULL, res_id, type, 0);
1168         if (res == NULL) {
1169                 LASSERT(old_lock == NULL);
1170                 RETURN(0);
1171         }
1172
1173         LDLM_RESOURCE_ADDREF(res);
1174         lock_res(res);
1175
1176         lock = search_queue(&res->lr_granted, &mode, policy, old_lock,
1177                             flags, unref);
1178         if (lock != NULL)
1179                 GOTO(out, rc = 1);
1180         if (flags & LDLM_FL_BLOCK_GRANTED)
1181                 GOTO(out, rc = 0);
1182         lock = search_queue(&res->lr_converting, &mode, policy, old_lock,
1183                             flags, unref);
1184         if (lock != NULL)
1185                 GOTO(out, rc = 1);
1186         lock = search_queue(&res->lr_waiting, &mode, policy, old_lock,
1187                             flags, unref);
1188         if (lock != NULL)
1189                 GOTO(out, rc = 1);
1190
1191         EXIT;
1192  out:
1193         unlock_res(res);
1194         LDLM_RESOURCE_DELREF(res);
1195         ldlm_resource_putref(res);
1196
1197         if (lock) {
1198                 ldlm_lock2handle(lock, lockh);
1199                 if ((flags & LDLM_FL_LVB_READY) &&
1200                     (!(lock->l_flags & LDLM_FL_LVB_READY))) {
1201                         struct l_wait_info lwi;
1202                         if (lock->l_completion_ast) {
1203                                 int err = lock->l_completion_ast(lock,
1204                                                           LDLM_FL_WAIT_NOREPROC,
1205                                                                  NULL);
1206                                 if (err) {
1207                                         if (flags & LDLM_FL_TEST_LOCK)
1208                                                 LDLM_LOCK_RELEASE(lock);
1209                                         else
1210                                                 ldlm_lock_decref_internal(lock,
1211                                                                           mode);
1212                                         rc = 0;
1213                                         goto out2;
1214                                 }
1215                         }
1216
1217                         lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(obd_timeout),
1218                                                NULL, LWI_ON_SIGNAL_NOOP, NULL);
1219
1220                         /* XXX FIXME see comment on CAN_MATCH in lustre_dlm.h */
1221                         l_wait_event(lock->l_waitq,
1222                                      lock->l_flags & LDLM_FL_LVB_READY ||
1223                                      lock->l_failed,
1224                                      &lwi);
1225                         if (!(lock->l_flags & LDLM_FL_LVB_READY)) {
1226                                 if (flags & LDLM_FL_TEST_LOCK)
1227                                         LDLM_LOCK_RELEASE(lock);
1228                                 else
1229                                         ldlm_lock_decref_internal(lock, mode);
1230                                 rc = 0;
1231                         }
1232                 }
1233         }
1234  out2:
1235         if (rc) {
1236                 LDLM_DEBUG(lock, "matched ("LPU64" "LPU64")",
1237                            (type == LDLM_PLAIN || type == LDLM_IBITS) ?
1238                                 res_id->name[2] : policy->l_extent.start,
1239                            (type == LDLM_PLAIN || type == LDLM_IBITS) ?
1240                                 res_id->name[3] : policy->l_extent.end);
1241
1242                 /* check user's security context */
1243                 if (lock->l_conn_export &&
1244                     sptlrpc_import_check_ctx(
1245                                 class_exp2cliimp(lock->l_conn_export))) {
1246                         if (!(flags & LDLM_FL_TEST_LOCK))
1247                                 ldlm_lock_decref_internal(lock, mode);
1248                         rc = 0;
1249                 }
1250
1251                 if (flags & LDLM_FL_TEST_LOCK)
1252                         LDLM_LOCK_RELEASE(lock);
1253
1254         } else if (!(flags & LDLM_FL_TEST_LOCK)) {/*less verbose for test-only*/
1255                 LDLM_DEBUG_NOLOCK("not matched ns %p type %u mode %u res "
1256                                   LPU64"/"LPU64" ("LPU64" "LPU64")", ns,
1257                                   type, mode, res_id->name[0], res_id->name[1],
1258                                   (type == LDLM_PLAIN || type == LDLM_IBITS) ?
1259                                         res_id->name[2] :policy->l_extent.start,
1260                                   (type == LDLM_PLAIN || type == LDLM_IBITS) ?
1261                                         res_id->name[3] : policy->l_extent.end);
1262         }
1263         if (old_lock)
1264                 LDLM_LOCK_PUT(old_lock);
1265
1266         return rc ? mode : 0;
1267 }
1268
1269 ldlm_mode_t ldlm_revalidate_lock_handle(struct lustre_handle *lockh,
1270                                         __u64 *bits)
1271 {
1272         struct ldlm_lock *lock;
1273         ldlm_mode_t mode = 0;
1274         ENTRY;
1275
1276         lock = ldlm_handle2lock(lockh);
1277         if (lock != NULL) {
1278                 lock_res_and_lock(lock);
1279                 if (lock->l_destroyed || lock->l_flags & LDLM_FL_FAILED ||
1280                     lock->l_failed)
1281                         GOTO(out, mode);
1282
1283                 if (lock->l_flags & LDLM_FL_CBPENDING &&
1284                     lock->l_readers == 0 && lock->l_writers == 0)
1285                         GOTO(out, mode);
1286
1287                 if (bits)
1288                         *bits = lock->l_policy_data.l_inodebits.bits;
1289                 mode = lock->l_granted_mode;
1290                 ldlm_lock_addref_internal_nolock(lock, mode);
1291         }
1292
1293         EXIT;
1294
1295 out:
1296         if (lock != NULL) {
1297                 unlock_res_and_lock(lock);
1298                 LDLM_LOCK_PUT(lock);
1299         }
1300         return mode;
1301 }
1302 EXPORT_SYMBOL(ldlm_revalidate_lock_handle);
1303
1304 /* Returns a referenced lock */
1305 struct ldlm_lock *ldlm_lock_create(struct ldlm_namespace *ns,
1306                                    const struct ldlm_res_id *res_id,
1307                                    ldlm_type_t type,
1308                                    ldlm_mode_t mode,
1309                                    const struct ldlm_callback_suite *cbs,
1310                                    void *data, __u32 lvb_len)
1311 {
1312         struct ldlm_lock *lock;
1313         struct ldlm_resource *res;
1314         ENTRY;
1315
1316         res = ldlm_resource_get(ns, NULL, res_id, type, 1);
1317         if (res == NULL)
1318                 RETURN(NULL);
1319
1320         lock = ldlm_lock_new(res);
1321
1322         if (lock == NULL)
1323                 RETURN(NULL);
1324
1325         lock->l_req_mode = mode;
1326         lock->l_ast_data = data;
1327         lock->l_pid = cfs_curproc_pid();
1328         lock->l_ns_srv = !!ns_is_server(ns);
1329         if (cbs) {
1330                 lock->l_blocking_ast = cbs->lcs_blocking;
1331                 lock->l_completion_ast = cbs->lcs_completion;
1332                 lock->l_glimpse_ast = cbs->lcs_glimpse;
1333                 lock->l_weigh_ast = cbs->lcs_weigh;
1334         }
1335
1336         lock->l_tree_node = NULL;
1337         /* if this is the extent lock, allocate the interval tree node */
1338         if (type == LDLM_EXTENT) {
1339                 if (ldlm_interval_alloc(lock) == NULL)
1340                         GOTO(out, 0);
1341         }
1342
1343         if (lvb_len) {
1344                 lock->l_lvb_len = lvb_len;
1345                 OBD_ALLOC(lock->l_lvb_data, lvb_len);
1346                 if (lock->l_lvb_data == NULL)
1347                         GOTO(out, 0);
1348         }
1349
1350         if (OBD_FAIL_CHECK(OBD_FAIL_LDLM_NEW_LOCK))
1351                 GOTO(out, 0);
1352
1353         RETURN(lock);
1354
1355 out:
1356         ldlm_lock_destroy(lock);
1357         LDLM_LOCK_RELEASE(lock);
1358         return NULL;
1359 }
1360
1361 ldlm_error_t ldlm_lock_enqueue(struct ldlm_namespace *ns,
1362                                struct ldlm_lock **lockp,
1363                                void *cookie, int *flags)
1364 {
1365         struct ldlm_lock *lock = *lockp;
1366         struct ldlm_resource *res = lock->l_resource;
1367         int local = ns_is_client(ldlm_res_to_ns(res));
1368 #ifdef HAVE_SERVER_SUPPORT
1369         ldlm_processing_policy policy;
1370 #endif
1371         ldlm_error_t rc = ELDLM_OK;
1372         struct ldlm_interval *node = NULL;
1373         ENTRY;
1374
1375         lock->l_last_activity = cfs_time_current_sec();
1376         /* policies are not executed on the client or during replay */
1377         if ((*flags & (LDLM_FL_HAS_INTENT|LDLM_FL_REPLAY)) == LDLM_FL_HAS_INTENT
1378             && !local && ns->ns_policy) {
1379                 rc = ns->ns_policy(ns, lockp, cookie, lock->l_req_mode, *flags,
1380                                    NULL);
1381                 if (rc == ELDLM_LOCK_REPLACED) {
1382                         /* The lock that was returned has already been granted,
1383                          * and placed into lockp.  If it's not the same as the
1384                          * one we passed in, then destroy the old one and our
1385                          * work here is done. */
1386                         if (lock != *lockp) {
1387                                 ldlm_lock_destroy(lock);
1388                                 LDLM_LOCK_RELEASE(lock);
1389                         }
1390                         *flags |= LDLM_FL_LOCK_CHANGED;
1391                         RETURN(0);
1392                 } else if (rc != ELDLM_OK ||
1393                            (rc == ELDLM_OK && (*flags & LDLM_FL_INTENT_ONLY))) {
1394                         ldlm_lock_destroy(lock);
1395                         RETURN(rc);
1396                 }
1397         }
1398
1399         /* For a replaying lock, it might be already in granted list. So
1400          * unlinking the lock will cause the interval node to be freed, we
1401          * have to allocate the interval node early otherwise we can't regrant
1402          * this lock in the future. - jay */
1403         if (!local && (*flags & LDLM_FL_REPLAY) && res->lr_type == LDLM_EXTENT)
1404                 OBD_SLAB_ALLOC_PTR_GFP(node, ldlm_interval_slab, CFS_ALLOC_IO);
1405
1406         lock_res_and_lock(lock);
1407         if (local && lock->l_req_mode == lock->l_granted_mode) {
1408                 /* The server returned a blocked lock, but it was granted
1409                  * before we got a chance to actually enqueue it.  We don't
1410                  * need to do anything else. */
1411                 *flags &= ~(LDLM_FL_BLOCK_GRANTED |
1412                             LDLM_FL_BLOCK_CONV | LDLM_FL_BLOCK_WAIT);
1413                 GOTO(out, ELDLM_OK);
1414         }
1415
1416         ldlm_resource_unlink_lock(lock);
1417         if (res->lr_type == LDLM_EXTENT && lock->l_tree_node == NULL) {
1418                 if (node == NULL) {
1419                         ldlm_lock_destroy_nolock(lock);
1420                         GOTO(out, rc = -ENOMEM);
1421                 }
1422
1423                 CFS_INIT_LIST_HEAD(&node->li_group);
1424                 ldlm_interval_attach(node, lock);
1425                 node = NULL;
1426         }
1427
1428         /* Some flags from the enqueue want to make it into the AST, via the
1429          * lock's l_flags. */
1430         lock->l_flags |= *flags & LDLM_AST_DISCARD_DATA;
1431
1432         /* This distinction between local lock trees is very important; a client
1433          * namespace only has information about locks taken by that client, and
1434          * thus doesn't have enough information to decide for itself if it can
1435          * be granted (below).  In this case, we do exactly what the server
1436          * tells us to do, as dictated by the 'flags'.
1437          *
1438          * We do exactly the same thing during recovery, when the server is
1439          * more or less trusting the clients not to lie.
1440          *
1441          * FIXME (bug 268): Detect obvious lies by checking compatibility in
1442          * granted/converting queues. */
1443         if (local) {
1444                 if (*flags & LDLM_FL_BLOCK_CONV)
1445                         ldlm_resource_add_lock(res, &res->lr_converting, lock);
1446                 else if (*flags & (LDLM_FL_BLOCK_WAIT | LDLM_FL_BLOCK_GRANTED))
1447                         ldlm_resource_add_lock(res, &res->lr_waiting, lock);
1448                 else
1449                         ldlm_grant_lock(lock, NULL);
1450                 GOTO(out, ELDLM_OK);
1451 #ifdef HAVE_SERVER_SUPPORT
1452         } else if (*flags & LDLM_FL_REPLAY) {
1453                 if (*flags & LDLM_FL_BLOCK_CONV) {
1454                         ldlm_resource_add_lock(res, &res->lr_converting, lock);
1455                         GOTO(out, ELDLM_OK);
1456                 } else if (*flags & LDLM_FL_BLOCK_WAIT) {
1457                         ldlm_resource_add_lock(res, &res->lr_waiting, lock);
1458                         GOTO(out, ELDLM_OK);
1459                 } else if (*flags & LDLM_FL_BLOCK_GRANTED) {
1460                         ldlm_grant_lock(lock, NULL);
1461                         GOTO(out, ELDLM_OK);
1462                 }
1463                 /* If no flags, fall through to normal enqueue path. */
1464         }
1465
1466         policy = ldlm_processing_policy_table[res->lr_type];
1467         policy(lock, flags, 1, &rc, NULL);
1468         GOTO(out, rc);
1469 #else
1470         } else {
1471                 CERROR("This is client-side-only module, cannot handle "
1472                        "LDLM_NAMESPACE_SERVER resource type lock.\n");
1473                 LBUG();
1474         }
1475 #endif
1476
1477 out:
1478         unlock_res_and_lock(lock);
1479         if (node)
1480                 OBD_SLAB_FREE(node, ldlm_interval_slab, sizeof(*node));
1481         return rc;
1482 }
1483
1484 #ifdef HAVE_SERVER_SUPPORT
1485 /* Must be called with namespace taken: queue is waiting or converting. */
1486 int ldlm_reprocess_queue(struct ldlm_resource *res, cfs_list_t *queue,
1487                          cfs_list_t *work_list)
1488 {
1489         cfs_list_t *tmp, *pos;
1490         ldlm_processing_policy policy;
1491         int flags;
1492         int rc = LDLM_ITER_CONTINUE;
1493         ldlm_error_t err;
1494         ENTRY;
1495
1496         check_res_locked(res);
1497
1498         policy = ldlm_processing_policy_table[res->lr_type];
1499         LASSERT(policy);
1500
1501         cfs_list_for_each_safe(tmp, pos, queue) {
1502                 struct ldlm_lock *pending;
1503                 pending = cfs_list_entry(tmp, struct ldlm_lock, l_res_link);
1504
1505                 CDEBUG(D_INFO, "Reprocessing lock %p\n", pending);
1506
1507                 flags = 0;
1508                 rc = policy(pending, &flags, 0, &err, work_list);
1509                 if (rc != LDLM_ITER_CONTINUE)
1510                         break;
1511         }
1512
1513         RETURN(rc);
1514 }
1515 #endif
1516
1517 static int
1518 ldlm_work_bl_ast_lock(cfs_list_t *tmp, struct ldlm_cb_set_arg *arg)
1519 {
1520         struct ldlm_lock_desc d;
1521         struct ldlm_lock *lock = cfs_list_entry(tmp, struct ldlm_lock,
1522                                                 l_bl_ast);
1523         int rc;
1524         ENTRY;
1525
1526         /* nobody should touch l_bl_ast */
1527         lock_res_and_lock(lock);
1528         cfs_list_del_init(&lock->l_bl_ast);
1529
1530         LASSERT(lock->l_flags & LDLM_FL_AST_SENT);
1531         LASSERT(lock->l_bl_ast_run == 0);
1532         LASSERT(lock->l_blocking_lock);
1533         lock->l_bl_ast_run++;
1534         unlock_res_and_lock(lock);
1535
1536         ldlm_lock2desc(lock->l_blocking_lock, &d);
1537
1538         rc = lock->l_blocking_ast(lock, &d, (void *)arg,
1539                                   LDLM_CB_BLOCKING);
1540         LDLM_LOCK_RELEASE(lock->l_blocking_lock);
1541         lock->l_blocking_lock = NULL;
1542         LDLM_LOCK_RELEASE(lock);
1543
1544         RETURN(rc);
1545 }
1546
1547 static int
1548 ldlm_work_cp_ast_lock(cfs_list_t *tmp, struct ldlm_cb_set_arg *arg)
1549 {
1550         struct ldlm_lock *lock = cfs_list_entry(tmp, struct ldlm_lock, l_cp_ast);
1551         ldlm_completion_callback completion_callback;
1552         int rc = 0;
1553         ENTRY;
1554
1555         /* It's possible to receive a completion AST before we've set
1556          * the l_completion_ast pointer: either because the AST arrived
1557          * before the reply, or simply because there's a small race
1558          * window between receiving the reply and finishing the local
1559          * enqueue. (bug 842)
1560          *
1561          * This can't happen with the blocking_ast, however, because we
1562          * will never call the local blocking_ast until we drop our
1563          * reader/writer reference, which we won't do until we get the
1564          * reply and finish enqueueing. */
1565
1566         /* nobody should touch l_cp_ast */
1567         lock_res_and_lock(lock);
1568         cfs_list_del_init(&lock->l_cp_ast);
1569         LASSERT(lock->l_flags & LDLM_FL_CP_REQD);
1570         /* save l_completion_ast since it can be changed by
1571          * mds_intent_policy(), see bug 14225 */
1572         completion_callback = lock->l_completion_ast;
1573         lock->l_flags &= ~LDLM_FL_CP_REQD;
1574         unlock_res_and_lock(lock);
1575
1576         if (completion_callback != NULL)
1577                 rc = completion_callback(lock, 0, (void *)arg);
1578         LDLM_LOCK_RELEASE(lock);
1579
1580         RETURN(rc);
1581 }
1582
1583 static int
1584 ldlm_work_revoke_ast_lock(cfs_list_t *tmp, struct ldlm_cb_set_arg *arg)
1585 {
1586         struct ldlm_lock_desc desc;
1587         struct ldlm_lock *lock = cfs_list_entry(tmp, struct ldlm_lock,
1588                                                 l_rk_ast);
1589         int rc;
1590         ENTRY;
1591
1592         cfs_list_del_init(&lock->l_rk_ast);
1593
1594         /* the desc just pretend to exclusive */
1595         ldlm_lock2desc(lock, &desc);
1596         desc.l_req_mode = LCK_EX;
1597         desc.l_granted_mode = 0;
1598
1599         rc = lock->l_blocking_ast(lock, &desc, (void*)arg, LDLM_CB_BLOCKING);
1600         LDLM_LOCK_RELEASE(lock);
1601
1602         RETURN(rc);
1603 }
1604
1605 int ldlm_run_ast_work(struct ldlm_namespace *ns, cfs_list_t *rpc_list,
1606                       ldlm_desc_ast_t ast_type)
1607 {
1608         struct l_wait_info     lwi = { 0 };
1609         struct ldlm_cb_set_arg *arg;
1610         cfs_list_t *tmp, *pos;
1611         int (*work_ast_lock)(cfs_list_t *tmp, struct ldlm_cb_set_arg *arg);
1612         unsigned int max_ast_count;
1613         int rc;
1614         ENTRY;
1615
1616         if (cfs_list_empty(rpc_list))
1617                 RETURN(0);
1618
1619         OBD_ALLOC_PTR(arg);
1620         if (arg == NULL)
1621                 RETURN(-ENOMEM);
1622
1623         cfs_atomic_set(&arg->restart, 0);
1624         cfs_atomic_set(&arg->rpcs, 0);
1625         cfs_atomic_set(&arg->refcount, 1);
1626         cfs_waitq_init(&arg->waitq);
1627
1628         switch (ast_type) {
1629         case LDLM_WORK_BL_AST:
1630                 arg->type = LDLM_BL_CALLBACK;
1631                 work_ast_lock = ldlm_work_bl_ast_lock;
1632                 break;
1633         case LDLM_WORK_CP_AST:
1634                 arg->type = LDLM_CP_CALLBACK;
1635                 work_ast_lock = ldlm_work_cp_ast_lock;
1636                 break;
1637         case LDLM_WORK_REVOKE_AST:
1638                 arg->type = LDLM_BL_CALLBACK;
1639                 work_ast_lock = ldlm_work_revoke_ast_lock;
1640                 break;
1641         default:
1642                 LBUG();
1643         }
1644
1645         max_ast_count = ns->ns_max_parallel_ast ? : UINT_MAX;
1646         arg->threshold = max_ast_count;
1647
1648         cfs_list_for_each_safe(tmp, pos, rpc_list) {
1649                 (void)work_ast_lock(tmp, arg);
1650                 if (cfs_atomic_read(&arg->rpcs) < max_ast_count)
1651                         continue;
1652
1653                 l_wait_event(arg->waitq,
1654                              cfs_atomic_read(&arg->rpcs) < arg->threshold,
1655                              &lwi);
1656         }
1657
1658         arg->threshold = 1;
1659         l_wait_event(arg->waitq, cfs_atomic_read(&arg->rpcs) == 0, &lwi);
1660
1661         rc = cfs_atomic_read(&arg->restart) ? -ERESTART : 0;
1662         ldlm_csa_put(arg);
1663         RETURN(rc);
1664 }
1665
1666 static int reprocess_one_queue(struct ldlm_resource *res, void *closure)
1667 {
1668         ldlm_reprocess_all(res);
1669         return LDLM_ITER_CONTINUE;
1670 }
1671
1672 static int ldlm_reprocess_res(cfs_hash_t *hs, cfs_hash_bd_t *bd,
1673                               cfs_hlist_node_t *hnode, void *arg)
1674 {
1675         struct ldlm_resource *res = cfs_hash_object(hs, hnode);
1676         int    rc;
1677
1678         rc = reprocess_one_queue(res, arg);
1679
1680         return rc == LDLM_ITER_STOP;
1681 }
1682
1683 void ldlm_reprocess_all_ns(struct ldlm_namespace *ns)
1684 {
1685         ENTRY;
1686
1687         if (ns != NULL) {
1688                 cfs_hash_for_each_nolock(ns->ns_rs_hash,
1689                                          ldlm_reprocess_res, NULL);
1690         }
1691         EXIT;
1692 }
1693
1694 void ldlm_reprocess_all(struct ldlm_resource *res)
1695 {
1696         CFS_LIST_HEAD(rpc_list);
1697
1698 #ifdef HAVE_SERVER_SUPPORT
1699         int rc;
1700         ENTRY;
1701         /* Local lock trees don't get reprocessed. */
1702         if (ns_is_client(ldlm_res_to_ns(res))) {
1703                 EXIT;
1704                 return;
1705         }
1706
1707 restart:
1708         lock_res(res);
1709         rc = ldlm_reprocess_queue(res, &res->lr_converting, &rpc_list);
1710         if (rc == LDLM_ITER_CONTINUE)
1711                 ldlm_reprocess_queue(res, &res->lr_waiting, &rpc_list);
1712         unlock_res(res);
1713
1714         rc = ldlm_run_ast_work(ldlm_res_to_ns(res), &rpc_list,
1715                                LDLM_WORK_CP_AST);
1716         if (rc == -ERESTART) {
1717                 LASSERT(cfs_list_empty(&rpc_list));
1718                 goto restart;
1719         }
1720 #else
1721         ENTRY;
1722         if (!ns_is_client(ldlm_res_to_ns(res))) {
1723                 CERROR("This is client-side-only module, cannot handle "
1724                        "LDLM_NAMESPACE_SERVER resource type lock.\n");
1725                 LBUG();
1726         }
1727 #endif
1728         EXIT;
1729 }
1730
1731 void ldlm_cancel_callback(struct ldlm_lock *lock)
1732 {
1733         check_res_locked(lock->l_resource);
1734         if (!(lock->l_flags & LDLM_FL_CANCEL)) {
1735                 lock->l_flags |= LDLM_FL_CANCEL;
1736                 if (lock->l_blocking_ast) {
1737                         // l_check_no_ns_lock(ns);
1738                         unlock_res_and_lock(lock);
1739                         lock->l_blocking_ast(lock, NULL, lock->l_ast_data,
1740                                              LDLM_CB_CANCELING);
1741                         lock_res_and_lock(lock);
1742                 } else {
1743                         LDLM_DEBUG(lock, "no blocking ast");
1744                 }
1745         }
1746         lock->l_flags |= LDLM_FL_BL_DONE;
1747 }
1748
1749 void ldlm_unlink_lock_skiplist(struct ldlm_lock *req)
1750 {
1751         if (req->l_resource->lr_type != LDLM_PLAIN &&
1752             req->l_resource->lr_type != LDLM_IBITS)
1753                 return;
1754
1755         cfs_list_del_init(&req->l_sl_policy);
1756         cfs_list_del_init(&req->l_sl_mode);
1757 }
1758
1759 void ldlm_lock_cancel(struct ldlm_lock *lock)
1760 {
1761         struct ldlm_resource *res;
1762         struct ldlm_namespace *ns;
1763         ENTRY;
1764
1765         lock_res_and_lock(lock);
1766
1767         res = lock->l_resource;
1768         ns  = ldlm_res_to_ns(res);
1769
1770         /* Please do not, no matter how tempting, remove this LBUG without
1771          * talking to me first. -phik */
1772         if (lock->l_readers || lock->l_writers) {
1773                 LDLM_ERROR(lock, "lock still has references");
1774                 LBUG();
1775         }
1776
1777         ldlm_del_waiting_lock(lock);
1778
1779         /* Releases cancel callback. */
1780         ldlm_cancel_callback(lock);
1781
1782         /* Yes, second time, just in case it was added again while we were
1783            running with no res lock in ldlm_cancel_callback */
1784         ldlm_del_waiting_lock(lock);
1785         ldlm_resource_unlink_lock(lock);
1786         ldlm_lock_destroy_nolock(lock);
1787
1788         if (lock->l_granted_mode == lock->l_req_mode)
1789                 ldlm_pool_del(&ns->ns_pool, lock);
1790
1791         /* Make sure we will not be called again for same lock what is possible
1792          * if not to zero out lock->l_granted_mode */
1793         lock->l_granted_mode = LCK_MINMODE;
1794         unlock_res_and_lock(lock);
1795
1796         EXIT;
1797 }
1798
1799 int ldlm_lock_set_data(struct lustre_handle *lockh, void *data)
1800 {
1801         struct ldlm_lock *lock = ldlm_handle2lock(lockh);
1802         int rc = -EINVAL;
1803         ENTRY;
1804
1805         if (lock) {
1806                 if (lock->l_ast_data == NULL)
1807                         lock->l_ast_data = data;
1808                 if (lock->l_ast_data == data)
1809                         rc = 0;
1810                 LDLM_LOCK_PUT(lock);
1811         }
1812         RETURN(rc);
1813 }
1814 EXPORT_SYMBOL(ldlm_lock_set_data);
1815
1816 int ldlm_cancel_locks_for_export_cb(cfs_hash_t *hs, cfs_hash_bd_t *bd,
1817                                     cfs_hlist_node_t *hnode, void *data)
1818
1819 {
1820         struct obd_export    *exp  = data;
1821         struct ldlm_lock     *lock = cfs_hash_object(hs, hnode);
1822         struct ldlm_resource *res;
1823
1824         res = ldlm_resource_getref(lock->l_resource);
1825         LDLM_LOCK_GET(lock);
1826
1827         LDLM_DEBUG(lock, "export %p", exp);
1828         ldlm_res_lvbo_update(res, NULL, 1);
1829         ldlm_lock_cancel(lock);
1830         ldlm_reprocess_all(res);
1831         ldlm_resource_putref(res);
1832         LDLM_LOCK_RELEASE(lock);
1833         return 0;
1834 }
1835
1836 void ldlm_cancel_locks_for_export(struct obd_export *exp)
1837 {
1838         cfs_hash_for_each_empty(exp->exp_lock_hash,
1839                                 ldlm_cancel_locks_for_export_cb, exp);
1840 }
1841
1842 /**
1843  * Downgrade an exclusive lock.
1844  *
1845  * A fast variant of ldlm_lock_convert for convertion of exclusive
1846  * locks. The convertion is always successful.
1847  *
1848  * \param lock A lock to convert
1849  * \param new_mode new lock mode
1850  */
1851 void ldlm_lock_downgrade(struct ldlm_lock *lock, int new_mode)
1852 {
1853         ENTRY;
1854
1855         LASSERT(lock->l_granted_mode & (LCK_PW | LCK_EX));
1856         LASSERT(new_mode == LCK_COS);
1857
1858         lock_res_and_lock(lock);
1859         ldlm_resource_unlink_lock(lock);
1860         /*
1861          * Remove the lock from pool as it will be added again in
1862          * ldlm_grant_lock() called below.
1863          */
1864         ldlm_pool_del(&ldlm_lock_to_ns(lock)->ns_pool, lock);
1865
1866         lock->l_req_mode = new_mode;
1867         ldlm_grant_lock(lock, NULL);
1868         unlock_res_and_lock(lock);
1869         ldlm_reprocess_all(lock->l_resource);
1870
1871         EXIT;
1872 }
1873
1874 struct ldlm_resource *ldlm_lock_convert(struct ldlm_lock *lock, int new_mode,
1875                                         __u32 *flags)
1876 {
1877         CFS_LIST_HEAD(rpc_list);
1878         struct ldlm_resource *res;
1879         struct ldlm_namespace *ns;
1880         int granted = 0;
1881         int old_mode;
1882         struct sl_insert_point prev;
1883         struct ldlm_interval *node;
1884         ENTRY;
1885
1886         if (new_mode == lock->l_granted_mode) { // No changes? Just return.
1887                 *flags |= LDLM_FL_BLOCK_GRANTED;
1888                 RETURN(lock->l_resource);
1889         }
1890
1891         /* I can't check the type of lock here because the bitlock of lock
1892          * is not held here, so do the allocation blindly. -jay */
1893         OBD_SLAB_ALLOC_PTR_GFP(node, ldlm_interval_slab, CFS_ALLOC_IO);
1894         if (node == NULL)  /* Actually, this causes EDEADLOCK to be returned */
1895                 RETURN(NULL);
1896
1897         LASSERTF((new_mode == LCK_PW && lock->l_granted_mode == LCK_PR),
1898                  "new_mode %u, granted %u\n", new_mode, lock->l_granted_mode);
1899
1900         lock_res_and_lock(lock);
1901
1902         res = lock->l_resource;
1903         ns  = ldlm_res_to_ns(res);
1904
1905         old_mode = lock->l_req_mode;
1906         lock->l_req_mode = new_mode;
1907         if (res->lr_type == LDLM_PLAIN || res->lr_type == LDLM_IBITS) {
1908                 /* remember the lock position where the lock might be
1909                  * added back to the granted list later and also
1910                  * remember the join mode for skiplist fixing. */
1911                 prev.res_link = lock->l_res_link.prev;
1912                 prev.mode_link = lock->l_sl_mode.prev;
1913                 prev.policy_link = lock->l_sl_policy.prev;
1914                 ldlm_resource_unlink_lock(lock);
1915         } else {
1916                 ldlm_resource_unlink_lock(lock);
1917                 if (res->lr_type == LDLM_EXTENT) {
1918                         /* FIXME: ugly code, I have to attach the lock to a
1919                          * interval node again since perhaps it will be granted
1920                          * soon */
1921                         CFS_INIT_LIST_HEAD(&node->li_group);
1922                         ldlm_interval_attach(node, lock);
1923                         node = NULL;
1924                 }
1925         }
1926
1927         /*
1928          * Remove old lock from the pool before adding the lock with new
1929          * mode below in ->policy()
1930          */
1931         ldlm_pool_del(&ns->ns_pool, lock);
1932
1933         /* If this is a local resource, put it on the appropriate list. */
1934         if (ns_is_client(ldlm_res_to_ns(res))) {
1935                 if (*flags & (LDLM_FL_BLOCK_CONV | LDLM_FL_BLOCK_GRANTED)) {
1936                         ldlm_resource_add_lock(res, &res->lr_converting, lock);
1937                 } else {
1938                         /* This should never happen, because of the way the
1939                          * server handles conversions. */
1940                         LDLM_ERROR(lock, "Erroneous flags %d on local lock\n",
1941                                    *flags);
1942                         LBUG();
1943
1944                         ldlm_grant_lock(lock, &rpc_list);
1945                         granted = 1;
1946                         /* FIXME: completion handling not with lr_lock held ! */
1947                         if (lock->l_completion_ast)
1948                                 lock->l_completion_ast(lock, 0, NULL);
1949                 }
1950 #ifdef HAVE_SERVER_SUPPORT
1951         } else {
1952                 int rc;
1953                 ldlm_error_t err;
1954                 int pflags = 0;
1955                 ldlm_processing_policy policy;
1956                 policy = ldlm_processing_policy_table[res->lr_type];
1957                 rc = policy(lock, &pflags, 0, &err, &rpc_list);
1958                 if (rc == LDLM_ITER_STOP) {
1959                         lock->l_req_mode = old_mode;
1960                         if (res->lr_type == LDLM_EXTENT)
1961                                 ldlm_extent_add_lock(res, lock);
1962                         else
1963                                 ldlm_granted_list_add_lock(lock, &prev);
1964
1965                         res = NULL;
1966                 } else {
1967                         *flags |= LDLM_FL_BLOCK_GRANTED;
1968                         granted = 1;
1969                 }
1970         }
1971 #else
1972         } else {
1973                 CERROR("This is client-side-only module, cannot handle "
1974                        "LDLM_NAMESPACE_SERVER resource type lock.\n");
1975                 LBUG();
1976         }
1977 #endif
1978         unlock_res_and_lock(lock);
1979
1980         if (granted)
1981                 ldlm_run_ast_work(ns, &rpc_list, LDLM_WORK_CP_AST);
1982         if (node)
1983                 OBD_SLAB_FREE(node, ldlm_interval_slab, sizeof(*node));
1984         RETURN(res);
1985 }
1986
1987 void ldlm_lock_dump(int level, struct ldlm_lock *lock, int pos)
1988 {
1989         struct obd_device *obd = NULL;
1990
1991         if (!((libcfs_debug | D_ERROR) & level))
1992                 return;
1993
1994         if (!lock) {
1995                 CDEBUG(level, "  NULL LDLM lock\n");
1996                 return;
1997         }
1998
1999         CDEBUG(level," -- Lock dump: %p/"LPX64" (rc: %d) (pos: %d) (pid: %d)\n",
2000                lock, lock->l_handle.h_cookie, cfs_atomic_read(&lock->l_refc),
2001                pos, lock->l_pid);
2002         if (lock->l_conn_export != NULL)
2003                 obd = lock->l_conn_export->exp_obd;
2004         if (lock->l_export && lock->l_export->exp_connection) {
2005                 CDEBUG(level, "  Node: NID %s (rhandle: "LPX64")\n",
2006                      libcfs_nid2str(lock->l_export->exp_connection->c_peer.nid),
2007                      lock->l_remote_handle.cookie);
2008         } else if (obd == NULL) {
2009                 CDEBUG(level, "  Node: local\n");
2010         } else {
2011                 struct obd_import *imp = obd->u.cli.cl_import;
2012                 CDEBUG(level, "  Node: NID %s (rhandle: "LPX64")\n",
2013                        libcfs_nid2str(imp->imp_connection->c_peer.nid),
2014                        lock->l_remote_handle.cookie);
2015         }
2016         CDEBUG(level, "  Resource: %p ("LPU64"/"LPU64"/"LPU64")\n",
2017                   lock->l_resource,
2018                   lock->l_resource->lr_name.name[0],
2019                   lock->l_resource->lr_name.name[1],
2020                   lock->l_resource->lr_name.name[2]);
2021         CDEBUG(level, "  Req mode: %s, grant mode: %s, rc: %u, read: %d, "
2022                "write: %d flags: "LPX64"\n", ldlm_lockname[lock->l_req_mode],
2023                ldlm_lockname[lock->l_granted_mode],
2024                cfs_atomic_read(&lock->l_refc), lock->l_readers, lock->l_writers,
2025                lock->l_flags);
2026         if (lock->l_resource->lr_type == LDLM_EXTENT)
2027                 CDEBUG(level, "  Extent: "LPU64" -> "LPU64
2028                        " (req "LPU64"-"LPU64")\n",
2029                        lock->l_policy_data.l_extent.start,
2030                        lock->l_policy_data.l_extent.end,
2031                        lock->l_req_extent.start, lock->l_req_extent.end);
2032         else if (lock->l_resource->lr_type == LDLM_FLOCK)
2033                 CDEBUG(level, "  Pid: %d Extent: "LPU64" -> "LPU64"\n",
2034                        lock->l_policy_data.l_flock.pid,
2035                        lock->l_policy_data.l_flock.start,
2036                        lock->l_policy_data.l_flock.end);
2037        else if (lock->l_resource->lr_type == LDLM_IBITS)
2038                 CDEBUG(level, "  Bits: "LPX64"\n",
2039                        lock->l_policy_data.l_inodebits.bits);
2040 }
2041
2042 void ldlm_lock_dump_handle(int level, struct lustre_handle *lockh)
2043 {
2044         struct ldlm_lock *lock;
2045
2046         if (!((libcfs_debug | D_ERROR) & level))
2047                 return;
2048
2049         lock = ldlm_handle2lock(lockh);
2050         if (lock == NULL)
2051                 return;
2052
2053         ldlm_lock_dump(D_OTHER, lock, 0);
2054
2055         LDLM_LOCK_PUT(lock);
2056 }
2057
2058 void _ldlm_lock_debug(struct ldlm_lock *lock,
2059                       struct libcfs_debug_msg_data *msgdata,
2060                       const char *fmt, ...)
2061 {
2062         va_list args;
2063
2064         va_start(args, fmt);
2065
2066         if (lock->l_resource == NULL) {
2067                 libcfs_debug_vmsg2(msgdata, fmt, args,
2068                        " ns: \?\? lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
2069                        "res: \?\? rrc=\?\? type: \?\?\? flags: "LPX64" remote: "
2070                        LPX64" expref: %d pid: %u timeout: %lu\n", lock,
2071                        lock->l_handle.h_cookie, cfs_atomic_read(&lock->l_refc),
2072                        lock->l_readers, lock->l_writers,
2073                        ldlm_lockname[lock->l_granted_mode],
2074                        ldlm_lockname[lock->l_req_mode],
2075                        lock->l_flags, lock->l_remote_handle.cookie,
2076                        lock->l_export ?
2077                        cfs_atomic_read(&lock->l_export->exp_refcount) : -99,
2078                        lock->l_pid, lock->l_callback_timeout);
2079                 va_end(args);
2080                 return;
2081         }
2082
2083         switch (lock->l_resource->lr_type) {
2084         case LDLM_EXTENT:
2085                 libcfs_debug_vmsg2(msgdata, fmt, args,
2086                        " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
2087                        "res: "LPU64"/"LPU64" rrc: %d type: %s ["LPU64"->"LPU64
2088                        "] (req "LPU64"->"LPU64") flags: "LPX64" remote: "LPX64
2089                        " expref: %d pid: %u timeout %lu\n",
2090                        ldlm_lock_to_ns_name(lock), lock,
2091                        lock->l_handle.h_cookie, cfs_atomic_read(&lock->l_refc),
2092                        lock->l_readers, lock->l_writers,
2093                        ldlm_lockname[lock->l_granted_mode],
2094                        ldlm_lockname[lock->l_req_mode],
2095                        lock->l_resource->lr_name.name[0],
2096                        lock->l_resource->lr_name.name[1],
2097                        cfs_atomic_read(&lock->l_resource->lr_refcount),
2098                        ldlm_typename[lock->l_resource->lr_type],
2099                        lock->l_policy_data.l_extent.start,
2100                        lock->l_policy_data.l_extent.end,
2101                        lock->l_req_extent.start, lock->l_req_extent.end,
2102                        lock->l_flags, lock->l_remote_handle.cookie,
2103                        lock->l_export ?
2104                        cfs_atomic_read(&lock->l_export->exp_refcount) : -99,
2105                        lock->l_pid, lock->l_callback_timeout);
2106                 break;
2107
2108         case LDLM_FLOCK:
2109                 libcfs_debug_vmsg2(msgdata, fmt, args,
2110                        " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
2111                        "res: "LPU64"/"LPU64" rrc: %d type: %s pid: %d "
2112                        "["LPU64"->"LPU64"] flags: "LPX64" remote: "LPX64
2113                        " expref: %d pid: %u timeout: %lu\n",
2114                        ldlm_lock_to_ns_name(lock), lock,
2115                        lock->l_handle.h_cookie, cfs_atomic_read(&lock->l_refc),
2116                        lock->l_readers, lock->l_writers,
2117                        ldlm_lockname[lock->l_granted_mode],
2118                        ldlm_lockname[lock->l_req_mode],
2119                        lock->l_resource->lr_name.name[0],
2120                        lock->l_resource->lr_name.name[1],
2121                        cfs_atomic_read(&lock->l_resource->lr_refcount),
2122                        ldlm_typename[lock->l_resource->lr_type],
2123                        lock->l_policy_data.l_flock.pid,
2124                        lock->l_policy_data.l_flock.start,
2125                        lock->l_policy_data.l_flock.end,
2126                        lock->l_flags, lock->l_remote_handle.cookie,
2127                        lock->l_export ?
2128                        cfs_atomic_read(&lock->l_export->exp_refcount) : -99,
2129                        lock->l_pid, lock->l_callback_timeout);
2130                 break;
2131
2132         case LDLM_IBITS:
2133                 libcfs_debug_vmsg2(msgdata, fmt, args,
2134                        " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
2135                        "res: "LPU64"/"LPU64" bits "LPX64" rrc: %d type: %s "
2136                        "flags: "LPX64" remote: "LPX64" expref: %d "
2137                        "pid: %u timeout: %lu\n",
2138                        ldlm_lock_to_ns_name(lock),
2139                        lock, lock->l_handle.h_cookie,
2140                        cfs_atomic_read (&lock->l_refc),
2141                        lock->l_readers, lock->l_writers,
2142                        ldlm_lockname[lock->l_granted_mode],
2143                        ldlm_lockname[lock->l_req_mode],
2144                        lock->l_resource->lr_name.name[0],
2145                        lock->l_resource->lr_name.name[1],
2146                        lock->l_policy_data.l_inodebits.bits,
2147                        cfs_atomic_read(&lock->l_resource->lr_refcount),
2148                        ldlm_typename[lock->l_resource->lr_type],
2149                        lock->l_flags, lock->l_remote_handle.cookie,
2150                        lock->l_export ?
2151                        cfs_atomic_read(&lock->l_export->exp_refcount) : -99,
2152                        lock->l_pid, lock->l_callback_timeout);
2153                 break;
2154
2155         default:
2156                 libcfs_debug_vmsg2(msgdata, fmt, args,
2157                        " ns: %s lock: %p/"LPX64" lrc: %d/%d,%d mode: %s/%s "
2158                        "res: "LPU64"/"LPU64" rrc: %d type: %s flags: "LPX64" "
2159                        "remote: "LPX64" expref: %d pid: %u timeout %lu\n",
2160                        ldlm_lock_to_ns_name(lock),
2161                        lock, lock->l_handle.h_cookie,
2162                        cfs_atomic_read (&lock->l_refc),
2163                        lock->l_readers, lock->l_writers,
2164                        ldlm_lockname[lock->l_granted_mode],
2165                        ldlm_lockname[lock->l_req_mode],
2166                        lock->l_resource->lr_name.name[0],
2167                        lock->l_resource->lr_name.name[1],
2168                        cfs_atomic_read(&lock->l_resource->lr_refcount),
2169                        ldlm_typename[lock->l_resource->lr_type],
2170                        lock->l_flags, lock->l_remote_handle.cookie,
2171                        lock->l_export ?
2172                        cfs_atomic_read(&lock->l_export->exp_refcount) : -99,
2173                        lock->l_pid, lock->l_callback_timeout);
2174                 break;
2175         }
2176         va_end(args);
2177 }
2178 EXPORT_SYMBOL(_ldlm_lock_debug);