lustre/ldlm/ldlm_flock.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 [sun.com URL with a
  20  * copy of GPLv2].
  21  *
  22  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  23  * CA 95054 USA or visit www.sun.com if you need additional information or
  24  * have any questions.
  25  *
  26  * GPL HEADER END
  27  */
  28 /*
  29  * Copyright  2008 Sun Microsystems, Inc. All rights reserved
  30  * Use is subject to license terms.
  31  *
  32  * Copyright (c) 2003 Hewlett-Packard Development Company LP.
  33  * Developed under the sponsorship of the US Government under
  34  * Subcontract No. B514193
  35  */
  36 /*
  37  * This file is part of Lustre, http://www.lustre.org/
  38  * Lustre is a trademark of Sun Microsystems, Inc.
  39  */
  40
  41 #define DEBUG_SUBSYSTEM S_LDLM
  42
  43 #ifdef __KERNEL__
  44 #include <lustre_dlm.h>
  45 #include <obd_support.h>
  46 #include <obd_class.h>
  47 #include <lustre_lib.h>
  48 #include <libcfs/list.h>
  49 #else
  50 #include <liblustre.h>
  51 #include <obd_class.h>
  52 #endif
  53
  54 #include "ldlm_internal.h"
  55
  56 #define l_flock_waitq   l_lru
  57
  58 /**
  59  * Wait queue for Posix lock deadlock detection, added with
  60  * ldlm_lock::l_flock_waitq.
  61  */
  62 static CFS_LIST_HEAD(ldlm_flock_waitq);
  63 /**
  64  * Lock protecting access to ldlm_flock_waitq.
  65  */
  66 spinlock_t ldlm_flock_waitq_lock = SPIN_LOCK_UNLOCKED;
  67
  68 int ldlm_flock_blocking_ast(struct ldlm_lock *lock, struct ldlm_lock_desc *desc,
  69                             void *data, int flag);
  70
  71 /**
  72  * list_for_remaining_safe - iterate over the remaining entries in a list
  73  *              and safeguard against removal of a list entry.
  74  * @pos:        the &struct list_head to use as a loop counter. pos MUST
  75  *              have been initialized prior to using it in this macro.
  76  * @n:          another &struct list_head to use as temporary storage
  77  * @head:       the head for your list.
  78  */
  79 #define list_for_remaining_safe(pos, n, head) \
  80         for (n = pos->next; pos != (head); pos = n, n = pos->next)
  81
  82 static inline int
  83 ldlm_same_flock_owner(struct ldlm_lock *lock, struct ldlm_lock *new)
  84 {
  85         return((new->l_policy_data.l_flock.pid ==
  86                 lock->l_policy_data.l_flock.pid) &&
  87                (new->l_export == lock->l_export));
  88 }
  89
  90 static inline int
  91 ldlm_flocks_overlap(struct ldlm_lock *lock, struct ldlm_lock *new)
  92 {
  93         return((new->l_policy_data.l_flock.start <=
  94                 lock->l_policy_data.l_flock.end) &&
  95                (new->l_policy_data.l_flock.end >=
  96                 lock->l_policy_data.l_flock.start));
  97 }
  98
  99 static inline void
 100 ldlm_flock_destroy(struct ldlm_lock *lock, ldlm_mode_t mode, int flags)
 101 {
 102         ENTRY;
 103
 104         LDLM_DEBUG(lock, "ldlm_flock_destroy(mode: %d, flags: 0x%x)",
 105                    mode, flags);
 106
 107         /* Safe to not lock here, since it should be empty anyway */
 108         LASSERT(list_empty(&lock->l_flock_waitq));
 109
 110         list_del_init(&lock->l_res_link);
 111         if (flags == LDLM_FL_WAIT_NOREPROC) {
 112                 /* client side - set a flag to prevent sending a CANCEL */
 113                 lock->l_flags |= LDLM_FL_LOCAL_ONLY | LDLM_FL_CBPENDING;
 114                 ldlm_lock_decref_internal(lock, mode);
 115         }
 116
 117         ldlm_lock_destroy_nolock(lock);
 118         EXIT;
 119 }
 120
 121 static int
 122 ldlm_flock_deadlock(struct ldlm_lock *req, struct ldlm_lock *blocking_lock)
 123 {
 124         struct obd_export *req_export = req->l_export;
 125         struct obd_export *blocking_export = blocking_lock->l_export;
 126         pid_t req_pid = req->l_policy_data.l_flock.pid;
 127         pid_t blocking_pid = blocking_lock->l_policy_data.l_flock.pid;
 128         struct ldlm_lock *lock;
 129
 130         spin_lock(&ldlm_flock_waitq_lock);
 131 restart:
 132         list_for_each_entry(lock, &ldlm_flock_waitq, l_flock_waitq) {
 133                 if ((lock->l_policy_data.l_flock.pid != blocking_pid) ||
 134                     (lock->l_export != blocking_export))
 135                         continue;
 136
 137                 blocking_pid = lock->l_policy_data.l_flock.blocking_pid;
 138                 blocking_export = (struct obd_export *)(long)
 139                         lock->l_policy_data.l_flock.blocking_export;
 140                 if (blocking_pid == req_pid && blocking_export == req_export) {
 141                         spin_unlock(&ldlm_flock_waitq_lock);
 142                         return 1;
 143                 }
 144
 145                 goto restart;
 146         }
 147         spin_unlock(&ldlm_flock_waitq_lock);
 148
 149         return 0;
 150 }
 151
 152 int
 153 ldlm_process_flock_lock(struct ldlm_lock *req, int *flags, int first_enq,
 154                         ldlm_error_t *err, struct list_head *work_list)
 155 {
 156         struct ldlm_resource *res = req->l_resource;
 157         struct ldlm_namespace *ns = res->lr_namespace;
 158         struct list_head *tmp;
 159         struct list_head *ownlocks = NULL;
 160         struct ldlm_lock *lock = NULL;
 161         struct ldlm_lock *new = req;
 162         struct ldlm_lock *new2 = NULL;
 163         ldlm_mode_t mode = req->l_req_mode;
 164         int local = ns_is_client(ns);
 165         int added = (mode == LCK_NL);
 166         int overlaps = 0;
 167         ENTRY;
 168
 169         CDEBUG(D_DLMTRACE, "flags %#x pid %u mode %u start "LPU64" end "LPU64
 170                "\n", *flags, new->l_policy_data.l_flock.pid, mode,
 171                req->l_policy_data.l_flock.start,
 172                req->l_policy_data.l_flock.end);
 173
 174         *err = ELDLM_OK;
 175
 176         if (local) {
 177                 /* No blocking ASTs are sent to the clients for
 178                  * Posix file & record locks */
 179                 req->l_blocking_ast = NULL;
 180         } else {
 181                 /* Called on the server for lock cancels. */
 182                 req->l_blocking_ast = ldlm_flock_blocking_ast;
 183         }
 184
 185         if ((*flags == LDLM_FL_WAIT_NOREPROC) || (mode == LCK_NL)) {
 186                 /* This loop determines where this processes locks start
 187                  * in the resource lr_granted list. */
 188                 list_for_each(tmp, &res->lr_granted) {
 189                         lock = list_entry(tmp, struct ldlm_lock, l_res_link);
 190                         if (ldlm_same_flock_owner(lock, req)) {
 191                                 ownlocks = tmp;
 192                                 break;
 193                         }
 194                 }
 195         } else {
 196                 lockmode_verify(mode);
 197
 198                 /* This loop determines if there are existing locks
 199                  * that conflict with the new lock request. */
 200                 list_for_each(tmp, &res->lr_granted) {
 201                         lock = list_entry(tmp, struct ldlm_lock, l_res_link);
 202
 203                         if (ldlm_same_flock_owner(lock, req)) {
 204                                 if (!ownlocks)
 205                                         ownlocks = tmp;
 206                                 continue;
 207                         }
 208
 209                         /* locks are compatible, overlap doesn't matter */
 210                         if (lockmode_compat(lock->l_granted_mode, mode))
 211                                 continue;
 212
 213                         if (!ldlm_flocks_overlap(lock, req))
 214                                 continue;
 215
 216                         if (!first_enq)
 217                                 RETURN(LDLM_ITER_CONTINUE);
 218
 219                         if (*flags & LDLM_FL_BLOCK_NOWAIT) {
 220                                 ldlm_flock_destroy(req, mode, *flags);
 221                                 *err = -EAGAIN;
 222                                 RETURN(LDLM_ITER_STOP);
 223                         }
 224
 225                         if (*flags & LDLM_FL_TEST_LOCK) {
 226                                 ldlm_flock_destroy(req, mode, *flags);
 227                                 req->l_req_mode = lock->l_granted_mode;
 228                                 req->l_policy_data.l_flock.pid =
 229                                         lock->l_policy_data.l_flock.pid;
 230                                 req->l_policy_data.l_flock.start =
 231                                         lock->l_policy_data.l_flock.start;
 232                                 req->l_policy_data.l_flock.end =
 233                                         lock->l_policy_data.l_flock.end;
 234                                 *flags |= LDLM_FL_LOCK_CHANGED;
 235                                 RETURN(LDLM_ITER_STOP);
 236                         }
 237
 238                         if (ldlm_flock_deadlock(req, lock)) {
 239                                 ldlm_flock_destroy(req, mode, *flags);
 240                                 *err = -EDEADLK;
 241                                 RETURN(LDLM_ITER_STOP);
 242                         }
 243
 244                         req->l_policy_data.l_flock.blocking_pid =
 245                                 lock->l_policy_data.l_flock.pid;
 246                         req->l_policy_data.l_flock.blocking_export =
 247                                 (long)(void *)lock->l_export;
 248
 249                         LASSERT(list_empty(&req->l_flock_waitq));
 250                         spin_lock(&ldlm_flock_waitq_lock);
 251                         list_add_tail(&req->l_flock_waitq, &ldlm_flock_waitq);
 252                         spin_unlock(&ldlm_flock_waitq_lock);
 253
 254                         ldlm_resource_add_lock(res, &res->lr_waiting, req);
 255                         *flags |= LDLM_FL_BLOCK_GRANTED;
 256                         RETURN(LDLM_ITER_STOP);
 257                 }
 258         }
 259
 260         if (*flags & LDLM_FL_TEST_LOCK) {
 261                 ldlm_flock_destroy(req, mode, *flags);
 262                 req->l_req_mode = LCK_NL;
 263                 *flags |= LDLM_FL_LOCK_CHANGED;
 264                 RETURN(LDLM_ITER_STOP);
 265         }
 266
 267         /* In case we had slept on this lock request take it off of the
 268          * deadlock detection waitq. */
 269         spin_lock(&ldlm_flock_waitq_lock);
 270         list_del_init(&req->l_flock_waitq);
 271         spin_unlock(&ldlm_flock_waitq_lock);
 272
 273         /* Scan the locks owned by this process that overlap this request.
 274          * We may have to merge or split existing locks. */
 275
 276         if (!ownlocks)
 277                 ownlocks = &res->lr_granted;
 278
 279         list_for_remaining_safe(ownlocks, tmp, &res->lr_granted) {
 280                 lock = list_entry(ownlocks, struct ldlm_lock, l_res_link);
 281
 282                 if (!ldlm_same_flock_owner(lock, new))
 283                         break;
 284
 285                 if (lock->l_granted_mode == mode) {
 286                         /* If the modes are the same then we need to process
 287                          * locks that overlap OR adjoin the new lock. The extra
 288                          * logic condition is necessary to deal with arithmetic
 289                          * overflow and underflow. */
 290                         if ((new->l_policy_data.l_flock.start >
 291                              (lock->l_policy_data.l_flock.end + 1))
 292                             && (lock->l_policy_data.l_flock.end !=
 293                                 OBD_OBJECT_EOF))
 294                                 continue;
 295
 296                         if ((new->l_policy_data.l_flock.end <
 297                              (lock->l_policy_data.l_flock.start - 1))
 298                             && (lock->l_policy_data.l_flock.start != 0))
 299                                 break;
 300
 301                         if (new->l_policy_data.l_flock.start <
 302                             lock->l_policy_data.l_flock.start) {
 303                                 lock->l_policy_data.l_flock.start =
 304                                         new->l_policy_data.l_flock.start;
 305                         } else {
 306                                 new->l_policy_data.l_flock.start =
 307                                         lock->l_policy_data.l_flock.start;
 308                         }
 309
 310                         if (new->l_policy_data.l_flock.end >
 311                             lock->l_policy_data.l_flock.end) {
 312                                 lock->l_policy_data.l_flock.end =
 313                                         new->l_policy_data.l_flock.end;
 314                         } else {
 315                                 new->l_policy_data.l_flock.end =
 316                                         lock->l_policy_data.l_flock.end;
 317                         }
 318
 319                         if (added) {
 320                                 ldlm_flock_destroy(lock, mode, *flags);
 321                         } else {
 322                                 new = lock;
 323                                 added = 1;
 324                         }
 325                         continue;
 326                 }
 327
 328                 if (new->l_policy_data.l_flock.start >
 329                     lock->l_policy_data.l_flock.end)
 330                         continue;
 331
 332                 if (new->l_policy_data.l_flock.end <
 333                     lock->l_policy_data.l_flock.start)
 334                         break;
 335
 336                 ++overlaps;
 337
 338                 if (new->l_policy_data.l_flock.start <=
 339                     lock->l_policy_data.l_flock.start) {
 340                         if (new->l_policy_data.l_flock.end <
 341                             lock->l_policy_data.l_flock.end) {
 342                                 lock->l_policy_data.l_flock.start =
 343                                         new->l_policy_data.l_flock.end + 1;
 344                                 break;
 345                         }
 346                         ldlm_flock_destroy(lock, lock->l_req_mode, *flags);
 347                         continue;
 348                 }
 349                 if (new->l_policy_data.l_flock.end >=
 350                     lock->l_policy_data.l_flock.end) {
 351                         lock->l_policy_data.l_flock.end =
 352                                 new->l_policy_data.l_flock.start - 1;
 353                         continue;
 354                 }
 355
 356                 /* split the existing lock into two locks */
 357
 358                 /* if this is an F_UNLCK operation then we could avoid
 359                  * allocating a new lock and use the req lock passed in
 360                  * with the request but this would complicate the reply
 361                  * processing since updates to req get reflected in the
 362                  * reply. The client side replays the lock request so
 363                  * it must see the original lock data in the reply. */
 364
 365                 /* XXX - if ldlm_lock_new() can sleep we should
 366                  * release the ns_lock, allocate the new lock,
 367                  * and restart processing this lock. */
 368                 new2 = ldlm_lock_create(ns, &res->lr_name, LDLM_FLOCK,
 369                                         lock->l_granted_mode, NULL, NULL, NULL,
 370                                         NULL, 0);
 371                 if (!new2) {
 372                         ldlm_flock_destroy(req, lock->l_granted_mode, *flags);
 373                         *err = -ENOLCK;
 374                         RETURN(LDLM_ITER_STOP);
 375                 }
 376
 377                 new2->l_granted_mode = lock->l_granted_mode;
 378                 new2->l_policy_data.l_flock.pid =
 379                         new->l_policy_data.l_flock.pid;
 380                 new2->l_policy_data.l_flock.start =
 381                         lock->l_policy_data.l_flock.start;
 382                 new2->l_policy_data.l_flock.end =
 383                         new->l_policy_data.l_flock.start - 1;
 384                 lock->l_policy_data.l_flock.start =
 385                         new->l_policy_data.l_flock.end + 1;
 386                 new2->l_conn_export = lock->l_conn_export;
 387                 if (lock->l_export != NULL) {
 388                         new2->l_export = class_export_get(lock->l_export);
 389                         spin_lock(&new2->l_export->exp_ldlm_data.led_lock);
 390                         list_add(&new2->l_export_chain,
 391                                  &new2->l_export->exp_ldlm_data.led_held_locks);
 392                         spin_unlock(&new2->l_export->exp_ldlm_data.led_lock);
 393                 }
 394                 if (*flags == LDLM_FL_WAIT_NOREPROC)
 395                         ldlm_lock_addref_internal(new2, lock->l_granted_mode);
 396
 397                 /* insert new2 at lock */
 398                 ldlm_resource_add_lock(res, ownlocks, new2);
 399                 LDLM_LOCK_PUT(new2);
 400                 break;
 401         }
 402
 403         /* At this point we're granting the lock request. */
 404         req->l_granted_mode = req->l_req_mode;
 405
 406         /* Add req to the granted queue before calling ldlm_reprocess_all(). */
 407         if (!added) {
 408                 list_del_init(&req->l_res_link);
 409                 /* insert new lock before ownlocks in list. */
 410                 ldlm_resource_add_lock(res, ownlocks, req);
 411         }
 412
 413         if (*flags != LDLM_FL_WAIT_NOREPROC) {
 414                 if (first_enq) {
 415                         /* If this is an unlock, reprocess the waitq and
 416                          * send completions ASTs for locks that can now be
 417                          * granted. The only problem with doing this
 418                          * reprocessing here is that the completion ASTs for
 419                          * newly granted locks will be sent before the unlock
 420                          * completion is sent. It shouldn't be an issue. Also
 421                          * note that ldlm_process_flock_lock() will recurse,
 422                          * but only once because first_enq will be false from
 423                          * ldlm_reprocess_queue. */
 424                         if ((mode == LCK_NL) && overlaps) {
 425                                 CFS_LIST_HEAD(rpc_list);
 426                                 int rc;
 427 restart:
 428                                 ldlm_reprocess_queue(res, &res->lr_waiting,
 429                                                      &rpc_list);
 430
 431                                 unlock_res(res);
 432                                 rc = ldlm_run_ast_work(&rpc_list, LDLM_WORK_BL_AST);
 433                                 lock_res(res);
 434                                 if (rc == -ERESTART)
 435                                         GOTO(restart, -ERESTART);
 436                        }
 437                 } else {
 438                         LASSERT(req->l_completion_ast);
 439                         ldlm_add_ast_work_item(req, NULL, work_list);
 440                 }
 441         }
 442
 443         /* In case we're reprocessing the requested lock we can't destroy
 444          * it until after calling ldlm_ast_work_item() above so that lawi()
 445          * can bump the reference count on req. Otherwise req could be freed
 446          * before the completion AST can be sent.  */
 447         if (added)
 448                 ldlm_flock_destroy(req, mode, *flags);
 449
 450         ldlm_resource_dump(D_OTHER, res);
 451         RETURN(LDLM_ITER_CONTINUE);
 452 }
 453
 454 struct ldlm_flock_wait_data {
 455         struct ldlm_lock *fwd_lock;
 456         int               fwd_generation;
 457 };
 458
 459 static void
 460 ldlm_flock_interrupted_wait(void *data)
 461 {
 462         struct ldlm_lock *lock;
 463         struct lustre_handle lockh;
 464         int rc;
 465         ENTRY;
 466
 467         lock = ((struct ldlm_flock_wait_data *)data)->fwd_lock;
 468
 469         /* take lock off the deadlock detection waitq. */
 470         spin_lock(&ldlm_flock_waitq_lock);
 471         list_del_init(&lock->l_flock_waitq);
 472         spin_unlock(&ldlm_flock_waitq_lock);
 473
 474         /* client side - set flag to prevent lock from being put on lru list */
 475         lock->l_flags |= LDLM_FL_CBPENDING;
 476
 477         ldlm_lock_decref_internal(lock, lock->l_req_mode);
 478         ldlm_lock2handle(lock, &lockh);
 479         rc = ldlm_cli_cancel(&lockh);
 480         if (rc != ELDLM_OK)
 481                 CERROR("ldlm_cli_cancel: %d\n", rc);
 482
 483         EXIT;
 484 }
 485
 486 int
 487 ldlm_flock_completion_ast(struct ldlm_lock *lock, int flags, void *data)
 488 {
 489         struct ldlm_namespace *ns;
 490         cfs_flock_t *getlk = lock->l_ast_data;
 491         struct ldlm_flock_wait_data fwd;
 492         struct obd_device *obd;
 493         struct obd_import *imp = NULL;
 494         ldlm_error_t err;
 495         int rc = 0;
 496         struct l_wait_info lwi;
 497         ENTRY;
 498
 499         CDEBUG(D_DLMTRACE, "flags: 0x%x data: %p getlk: %p\n",
 500                flags, data, getlk);
 501
 502         /* Import invalidation. We need to actually release the lock
 503          * references being held, so that it can go away. No point in
 504          * holding the lock even if app still believes it has it, since
 505          * server already dropped it anyway. Only for granted locks too. */
 506         lock_res_and_lock(lock);
 507         if ((lock->l_flags & (LDLM_FL_FAILED|LDLM_FL_LOCAL_ONLY)) ==
 508             (LDLM_FL_FAILED|LDLM_FL_LOCAL_ONLY)) {
 509                 unlock_res_and_lock(lock);
 510                 if (lock->l_req_mode == lock->l_granted_mode &&
 511                     lock->l_granted_mode != LCK_NL)
 512                         ldlm_lock_decref_internal(lock, lock->l_req_mode);
 513                 RETURN(0);
 514         }
 515         unlock_res_and_lock(lock);
 516
 517         LASSERT(flags != LDLM_FL_WAIT_NOREPROC);
 518
 519         if (!(flags & (LDLM_FL_BLOCK_WAIT | LDLM_FL_BLOCK_GRANTED |
 520                        LDLM_FL_BLOCK_CONV)))
 521                 goto  granted;
 522
 523         LDLM_DEBUG(lock, "client-side enqueue returned a blocked lock, "
 524                    "sleeping");
 525
 526         fwd.fwd_lock = lock;
 527         obd = class_exp2obd(lock->l_conn_export);
 528
 529         /* if this is a local lock, then there is no import */
 530         if (obd != NULL)
 531                 imp = obd->u.cli.cl_import;
 532
 533         if (imp != NULL) {
 534                 spin_lock(&imp->imp_lock);
 535                 fwd.fwd_generation = imp->imp_generation;
 536                 spin_unlock(&imp->imp_lock);
 537         }
 538
 539         lwi = LWI_TIMEOUT_INTR(0, NULL, ldlm_flock_interrupted_wait, &fwd);
 540
 541         /* Go to sleep until the lock is granted. */
 542         rc = l_wait_event(lock->l_waitq,
 543                           ((lock->l_req_mode == lock->l_granted_mode) ||
 544                            lock->l_destroyed), &lwi);
 545
 546         LDLM_DEBUG(lock, "client-side enqueue waking up: rc = %d", rc);
 547         RETURN(rc);
 548
 549 granted:
 550         /* before flock's complete ast gets here, the flock
 551          * can possibly be freed by another thread
 552          */
 553         if (lock->l_destroyed) {
 554                 LDLM_DEBUG(lock, "already destroyed by another thread");
 555                 RETURN(0);
 556         }
 557
 558         LDLM_DEBUG(lock, "client-side enqueue granted");
 559         ns = lock->l_resource->lr_namespace;
 560         lock_res(lock->l_resource);
 561
 562         /* take lock off the deadlock detection waitq. */
 563         spin_lock(&ldlm_flock_waitq_lock);
 564         list_del_init(&lock->l_flock_waitq);
 565         spin_unlock(&ldlm_flock_waitq_lock);
 566
 567         /* ldlm_lock_enqueue() has already placed lock on the granted list. */
 568         list_del_init(&lock->l_res_link);
 569
 570         if (flags & LDLM_FL_TEST_LOCK) {
 571                 /* fcntl(F_GETLK) request */
 572                 /* The old mode was saved in getlk->fl_type so that if the mode
 573                  * in the lock changes we can decref the approprate refcount. */
 574                 ldlm_flock_destroy(lock, cfs_flock_type(getlk), LDLM_FL_WAIT_NOREPROC);
 575                 switch (lock->l_granted_mode) {
 576                 case LCK_PR:
 577                         cfs_flock_set_type(getlk, F_RDLCK);
 578                         break;
 579                 case LCK_PW:
 580                         cfs_flock_set_type(getlk, F_WRLCK);
 581                         break;
 582                 default:
 583                         cfs_flock_set_type(getlk, F_UNLCK);
 584                 }
 585                 cfs_flock_set_pid(getlk, (pid_t)lock->l_policy_data.l_flock.pid);
 586                 cfs_flock_set_start(getlk, (loff_t)lock->l_policy_data.l_flock.start);
 587                 cfs_flock_set_end(getlk, (loff_t)lock->l_policy_data.l_flock.end);
 588         } else {
 589                 int noreproc = LDLM_FL_WAIT_NOREPROC;
 590
 591                 /* We need to reprocess the lock to do merges or splits
 592                  * with existing locks owned by this process. */
 593                 ldlm_process_flock_lock(lock, &noreproc, 1, &err, NULL);
 594                 if (flags == 0)
 595                         cfs_waitq_signal(&lock->l_waitq);
 596         }
 597         unlock_res(lock->l_resource);
 598         RETURN(0);
 599 }
 600 EXPORT_SYMBOL(ldlm_flock_completion_ast);
 601
 602 int ldlm_flock_blocking_ast(struct ldlm_lock *lock, struct ldlm_lock_desc *desc,
 603                             void *data, int flag)
 604 {
 605         struct ldlm_namespace *ns;
 606         ENTRY;
 607
 608         LASSERT(lock);
 609         LASSERT(flag == LDLM_CB_CANCELING);
 610
 611         ns = lock->l_resource->lr_namespace;
 612
 613         /* take lock off the deadlock detection waitq. */
 614         spin_lock(&ldlm_flock_waitq_lock);
 615         list_del_init(&lock->l_flock_waitq);
 616         spin_unlock(&ldlm_flock_waitq_lock);
 617         RETURN(0);
 618 }