lustre/ldlm/ldlm_flock.c

   1 /*
   2  * GPL HEADER START
   3  *
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License version 2 for more details (a copy is included
  14  * in the LICENSE file that accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * version 2 along with this program; If not, see
  18  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  19  *
  20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  21  * CA 95054 USA or visit www.sun.com if you need additional information or
  22  * have any questions.
  23  *
  24  * GPL HEADER END
  25  */
  26 /*
  27  * Copyright (c) 2003 Hewlett-Packard Development Company LP.
  28  * Developed under the sponsorship of the US Government under
  29  * Subcontract No. B514193
  30  *
  31  * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
  32  * Use is subject to license terms.
  33  *
  34  * Copyright (c) 2010, 2011, Whamcloud, Inc.
  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 int ldlm_flock_blocking_ast(struct ldlm_lock *lock, struct ldlm_lock_desc *desc,
  59                             void *data, int flag);
  60
  61 /**
  62  * list_for_remaining_safe - iterate over the remaining entries in a list
  63  *              and safeguard against removal of a list entry.
  64  * \param pos   the &struct list_head to use as a loop counter. pos MUST
  65  *              have been initialized prior to using it in this macro.
  66  * \param n     another &struct list_head to use as temporary storage
  67  * \param head  the head for your list.
  68  */
  69 #define list_for_remaining_safe(pos, n, head) \
  70         for (n = pos->next; pos != (head); pos = n, n = pos->next)
  71
  72 static inline int
  73 ldlm_same_flock_owner(struct ldlm_lock *lock, struct ldlm_lock *new)
  74 {
  75         return((new->l_policy_data.l_flock.owner ==
  76                 lock->l_policy_data.l_flock.owner) &&
  77                (new->l_export == lock->l_export));
  78 }
  79
  80 static inline int
  81 ldlm_flocks_overlap(struct ldlm_lock *lock, struct ldlm_lock *new)
  82 {
  83         return((new->l_policy_data.l_flock.start <=
  84                 lock->l_policy_data.l_flock.end) &&
  85                (new->l_policy_data.l_flock.end >=
  86                 lock->l_policy_data.l_flock.start));
  87 }
  88
  89 static inline void ldlm_flock_blocking_link(struct ldlm_lock *req,
  90                                             struct ldlm_lock *lock)
  91 {
  92         /* For server only */
  93         if (req->l_export == NULL)
  94                 return;
  95
  96         LASSERT(cfs_list_empty(&req->l_flock_waitq));
  97         cfs_write_lock(&req->l_export->exp_flock_wait_lock);
  98
  99         req->l_policy_data.l_flock.blocking_owner =
 100                 lock->l_policy_data.l_flock.owner;
 101         req->l_policy_data.l_flock.blocking_export =
 102                 class_export_get(lock->l_export);
 103
 104         cfs_list_add_tail(&req->l_flock_waitq,
 105                           &req->l_export->exp_flock_wait_list);
 106         cfs_write_unlock(&req->l_export->exp_flock_wait_lock);
 107 }
 108
 109 static inline void ldlm_flock_blocking_unlink(struct ldlm_lock *req)
 110 {
 111         /* For server only */
 112         if (req->l_export == NULL)
 113                 return;
 114
 115         cfs_write_lock(&req->l_export->exp_flock_wait_lock);
 116         if (!cfs_list_empty(&req->l_flock_waitq)) {
 117                 cfs_list_del_init(&req->l_flock_waitq);
 118
 119                 class_export_put(req->l_policy_data.l_flock.blocking_export);
 120                 req->l_policy_data.l_flock.blocking_owner = 0;
 121                 req->l_policy_data.l_flock.blocking_export = NULL;
 122         }
 123         cfs_write_unlock(&req->l_export->exp_flock_wait_lock);
 124 }
 125
 126 static inline void
 127 ldlm_flock_destroy(struct ldlm_lock *lock, ldlm_mode_t mode, int flags)
 128 {
 129         ENTRY;
 130
 131         LDLM_DEBUG(lock, "ldlm_flock_destroy(mode: %d, flags: 0x%x)",
 132                    mode, flags);
 133
 134         /* Safe to not lock here, since it should be empty anyway */
 135         LASSERT(cfs_list_empty(&lock->l_flock_waitq));
 136
 137         cfs_list_del_init(&lock->l_res_link);
 138         if (flags == LDLM_FL_WAIT_NOREPROC &&
 139             !(lock->l_flags & LDLM_FL_FAILED)) {
 140                 /* client side - set a flag to prevent sending a CANCEL */
 141                 lock->l_flags |= LDLM_FL_LOCAL_ONLY | LDLM_FL_CBPENDING;
 142
 143                 /* when reaching here, it is under lock_res_and_lock(). Thus,
 144                    need call the nolock version of ldlm_lock_decref_internal*/
 145                 ldlm_lock_decref_internal_nolock(lock, mode);
 146         }
 147
 148         ldlm_lock_destroy_nolock(lock);
 149         EXIT;
 150 }
 151
 152 static int
 153 ldlm_flock_deadlock(struct ldlm_lock *req, struct ldlm_lock *bl_lock)
 154 {
 155         struct obd_export *req_exp = req->l_export;
 156         struct obd_export *bl_exp = bl_lock->l_export;
 157         struct obd_export *bl_exp_new;
 158         __u64 req_owner = req->l_policy_data.l_flock.owner;
 159         __u64 bl_owner = bl_lock->l_policy_data.l_flock.owner;
 160         struct ldlm_lock *lock;
 161
 162         /* For server only */
 163         if (req_exp == NULL)
 164                 return 0;
 165
 166         class_export_get(bl_exp);
 167 restart:
 168         cfs_read_lock(&bl_exp->exp_flock_wait_lock);
 169         cfs_list_for_each_entry(lock, &bl_exp->exp_flock_wait_list,
 170                                 l_flock_waitq) {
 171                 struct ldlm_flock *flock = &lock->l_policy_data.l_flock;
 172
 173                 /* want to find something from same client and same process */
 174                 if (flock->owner != bl_owner)
 175                         continue;
 176
 177                 bl_owner = flock->blocking_owner;
 178                 bl_exp_new = class_export_get(flock->blocking_export);
 179                 cfs_read_unlock(&bl_exp->exp_flock_wait_lock);
 180                 class_export_put(bl_exp);
 181                 bl_exp = bl_exp_new;
 182
 183                 if (bl_owner == req_owner && bl_exp == req_exp) {
 184                         class_export_put(bl_exp);
 185                         return 1;
 186                 }
 187
 188                 goto restart;
 189         }
 190         cfs_read_unlock(&bl_exp->exp_flock_wait_lock);
 191         class_export_put(bl_exp);
 192
 193         return 0;
 194 }
 195
 196 int
 197 ldlm_process_flock_lock(struct ldlm_lock *req, int *flags, int first_enq,
 198                         ldlm_error_t *err, cfs_list_t *work_list)
 199 {
 200         struct ldlm_resource *res = req->l_resource;
 201         struct ldlm_namespace *ns = ldlm_res_to_ns(res);
 202         cfs_list_t *tmp;
 203         cfs_list_t *ownlocks = NULL;
 204         struct ldlm_lock *lock = NULL;
 205         struct ldlm_lock *new = req;
 206         struct ldlm_lock *new2 = NULL;
 207         ldlm_mode_t mode = req->l_req_mode;
 208         int local = ns_is_client(ns);
 209         int added = (mode == LCK_NL);
 210         int overlaps = 0;
 211         int splitted = 0;
 212         const struct ldlm_callback_suite null_cbs = { NULL };
 213         ENTRY;
 214
 215         CDEBUG(D_DLMTRACE, "flags %#x owner "LPU64" pid %u mode %u start "LPU64
 216                " end "LPU64"\n", *flags, new->l_policy_data.l_flock.owner,
 217                new->l_policy_data.l_flock.pid, mode,
 218                req->l_policy_data.l_flock.start,
 219                req->l_policy_data.l_flock.end);
 220
 221         *err = ELDLM_OK;
 222
 223         if (local) {
 224                 /* No blocking ASTs are sent to the clients for
 225                  * Posix file & record locks */
 226                 req->l_blocking_ast = NULL;
 227         } else {
 228                 /* Called on the server for lock cancels. */
 229                 req->l_blocking_ast = ldlm_flock_blocking_ast;
 230         }
 231
 232 reprocess:
 233         if ((*flags == LDLM_FL_WAIT_NOREPROC) || (mode == LCK_NL)) {
 234                 /* This loop determines where this processes locks start
 235                  * in the resource lr_granted list. */
 236                 cfs_list_for_each(tmp, &res->lr_granted) {
 237                         lock = cfs_list_entry(tmp, struct ldlm_lock,
 238                                               l_res_link);
 239                         if (ldlm_same_flock_owner(lock, req)) {
 240                                 ownlocks = tmp;
 241                                 break;
 242                         }
 243                 }
 244         } else {
 245                 lockmode_verify(mode);
 246
 247                 /* This loop determines if there are existing locks
 248                  * that conflict with the new lock request. */
 249                 cfs_list_for_each(tmp, &res->lr_granted) {
 250                         lock = cfs_list_entry(tmp, struct ldlm_lock,
 251                                               l_res_link);
 252
 253                         if (ldlm_same_flock_owner(lock, req)) {
 254                                 if (!ownlocks)
 255                                         ownlocks = tmp;
 256                                 continue;
 257                         }
 258
 259                         /* locks are compatible, overlap doesn't matter */
 260                         if (lockmode_compat(lock->l_granted_mode, mode))
 261                                 continue;
 262
 263                         if (!ldlm_flocks_overlap(lock, req))
 264                                 continue;
 265
 266                         if (!first_enq)
 267                                 RETURN(LDLM_ITER_CONTINUE);
 268
 269                         if (*flags & LDLM_FL_BLOCK_NOWAIT) {
 270                                 ldlm_flock_destroy(req, mode, *flags);
 271                                 *err = -EAGAIN;
 272                                 RETURN(LDLM_ITER_STOP);
 273                         }
 274
 275                         if (*flags & LDLM_FL_TEST_LOCK) {
 276                                 ldlm_flock_destroy(req, mode, *flags);
 277                                 req->l_req_mode = lock->l_granted_mode;
 278                                 req->l_policy_data.l_flock.pid =
 279                                         lock->l_policy_data.l_flock.pid;
 280                                 req->l_policy_data.l_flock.start =
 281                                         lock->l_policy_data.l_flock.start;
 282                                 req->l_policy_data.l_flock.end =
 283                                         lock->l_policy_data.l_flock.end;
 284                                 *flags |= LDLM_FL_LOCK_CHANGED;
 285                                 RETURN(LDLM_ITER_STOP);
 286                         }
 287
 288                         if (ldlm_flock_deadlock(req, lock)) {
 289                                 ldlm_flock_destroy(req, mode, *flags);
 290                                 *err = -EDEADLK;
 291                                 RETURN(LDLM_ITER_STOP);
 292                         }
 293
 294
 295                         ldlm_flock_blocking_link(req, lock);
 296                         ldlm_resource_add_lock(res, &res->lr_waiting, req);
 297                         *flags |= LDLM_FL_BLOCK_GRANTED;
 298                         RETURN(LDLM_ITER_STOP);
 299                 }
 300         }
 301
 302         if (*flags & LDLM_FL_TEST_LOCK) {
 303                 ldlm_flock_destroy(req, mode, *flags);
 304                 req->l_req_mode = LCK_NL;
 305                 *flags |= LDLM_FL_LOCK_CHANGED;
 306                 RETURN(LDLM_ITER_STOP);
 307         }
 308
 309         /* In case we had slept on this lock request take it off of the
 310          * deadlock detection waitq. */
 311         ldlm_flock_blocking_unlink(req);
 312
 313         /* Scan the locks owned by this process that overlap this request.
 314          * We may have to merge or split existing locks. */
 315
 316         if (!ownlocks)
 317                 ownlocks = &res->lr_granted;
 318
 319         list_for_remaining_safe(ownlocks, tmp, &res->lr_granted) {
 320                 lock = cfs_list_entry(ownlocks, struct ldlm_lock, l_res_link);
 321
 322                 if (!ldlm_same_flock_owner(lock, new))
 323                         break;
 324
 325                 if (lock->l_granted_mode == mode) {
 326                         /* If the modes are the same then we need to process
 327                          * locks that overlap OR adjoin the new lock. The extra
 328                          * logic condition is necessary to deal with arithmetic
 329                          * overflow and underflow. */
 330                         if ((new->l_policy_data.l_flock.start >
 331                              (lock->l_policy_data.l_flock.end + 1))
 332                             && (lock->l_policy_data.l_flock.end !=
 333                                 OBD_OBJECT_EOF))
 334                                 continue;
 335
 336                         if ((new->l_policy_data.l_flock.end <
 337                              (lock->l_policy_data.l_flock.start - 1))
 338                             && (lock->l_policy_data.l_flock.start != 0))
 339                                 break;
 340
 341                         if (new->l_policy_data.l_flock.start <
 342                             lock->l_policy_data.l_flock.start) {
 343                                 lock->l_policy_data.l_flock.start =
 344                                         new->l_policy_data.l_flock.start;
 345                         } else {
 346                                 new->l_policy_data.l_flock.start =
 347                                         lock->l_policy_data.l_flock.start;
 348                         }
 349
 350                         if (new->l_policy_data.l_flock.end >
 351                             lock->l_policy_data.l_flock.end) {
 352                                 lock->l_policy_data.l_flock.end =
 353                                         new->l_policy_data.l_flock.end;
 354                         } else {
 355                                 new->l_policy_data.l_flock.end =
 356                                         lock->l_policy_data.l_flock.end;
 357                         }
 358
 359                         if (added) {
 360                                 ldlm_flock_destroy(lock, mode, *flags);
 361                         } else {
 362                                 new = lock;
 363                                 added = 1;
 364                         }
 365                         continue;
 366                 }
 367
 368                 if (new->l_policy_data.l_flock.start >
 369                     lock->l_policy_data.l_flock.end)
 370                         continue;
 371
 372                 if (new->l_policy_data.l_flock.end <
 373                     lock->l_policy_data.l_flock.start)
 374                         break;
 375
 376                 ++overlaps;
 377
 378                 if (new->l_policy_data.l_flock.start <=
 379                     lock->l_policy_data.l_flock.start) {
 380                         if (new->l_policy_data.l_flock.end <
 381                             lock->l_policy_data.l_flock.end) {
 382                                 lock->l_policy_data.l_flock.start =
 383                                         new->l_policy_data.l_flock.end + 1;
 384                                 break;
 385                         }
 386                         ldlm_flock_destroy(lock, lock->l_req_mode, *flags);
 387                         continue;
 388                 }
 389                 if (new->l_policy_data.l_flock.end >=
 390                     lock->l_policy_data.l_flock.end) {
 391                         lock->l_policy_data.l_flock.end =
 392                                 new->l_policy_data.l_flock.start - 1;
 393                         continue;
 394                 }
 395
 396                 /* split the existing lock into two locks */
 397
 398                 /* if this is an F_UNLCK operation then we could avoid
 399                  * allocating a new lock and use the req lock passed in
 400                  * with the request but this would complicate the reply
 401                  * processing since updates to req get reflected in the
 402                  * reply. The client side replays the lock request so
 403                  * it must see the original lock data in the reply. */
 404
 405                 /* XXX - if ldlm_lock_new() can sleep we should
 406                  * release the lr_lock, allocate the new lock,
 407                  * and restart processing this lock. */
 408                 if (!new2) {
 409                         unlock_res_and_lock(req);
 410                          new2 = ldlm_lock_create(ns, &res->lr_name, LDLM_FLOCK,
 411                                         lock->l_granted_mode, &null_cbs,
 412                                         NULL, 0);
 413                         lock_res_and_lock(req);
 414                         if (!new2) {
 415                                 ldlm_flock_destroy(req, lock->l_granted_mode,
 416                                                    *flags);
 417                                 *err = -ENOLCK;
 418                                 RETURN(LDLM_ITER_STOP);
 419                         }
 420                         goto reprocess;
 421                 }
 422
 423                 splitted = 1;
 424
 425                 new2->l_granted_mode = lock->l_granted_mode;
 426                 new2->l_policy_data.l_flock.pid =
 427                         new->l_policy_data.l_flock.pid;
 428                 new2->l_policy_data.l_flock.owner =
 429                         new->l_policy_data.l_flock.owner;
 430                 new2->l_policy_data.l_flock.start =
 431                         lock->l_policy_data.l_flock.start;
 432                 new2->l_policy_data.l_flock.end =
 433                         new->l_policy_data.l_flock.start - 1;
 434                 lock->l_policy_data.l_flock.start =
 435                         new->l_policy_data.l_flock.end + 1;
 436                 new2->l_conn_export = lock->l_conn_export;
 437                 if (lock->l_export != NULL) {
 438                         new2->l_export = class_export_lock_get(lock->l_export, new2);
 439                         if (new2->l_export->exp_lock_hash &&
 440                             cfs_hlist_unhashed(&new2->l_exp_hash))
 441                                 cfs_hash_add(new2->l_export->exp_lock_hash,
 442                                              &new2->l_remote_handle,
 443                                              &new2->l_exp_hash);
 444                 }
 445                 if (*flags == LDLM_FL_WAIT_NOREPROC)
 446                         ldlm_lock_addref_internal_nolock(new2,
 447                                                          lock->l_granted_mode);
 448
 449                 /* insert new2 at lock */
 450                 ldlm_resource_add_lock(res, ownlocks, new2);
 451                 LDLM_LOCK_RELEASE(new2);
 452                 break;
 453         }
 454
 455         /* if new2 is created but never used, destroy it*/
 456         if (splitted == 0 && new2 != NULL)
 457                 ldlm_lock_destroy_nolock(new2);
 458
 459         /* At this point we're granting the lock request. */
 460         req->l_granted_mode = req->l_req_mode;
 461
 462         /* Add req to the granted queue before calling ldlm_reprocess_all(). */
 463         if (!added) {
 464                 cfs_list_del_init(&req->l_res_link);
 465                 /* insert new lock before ownlocks in list. */
 466                 ldlm_resource_add_lock(res, ownlocks, req);
 467         }
 468
 469         if (*flags != LDLM_FL_WAIT_NOREPROC) {
 470 #ifdef HAVE_SERVER_SUPPORT
 471                 if (first_enq) {
 472                         /* If this is an unlock, reprocess the waitq and
 473                          * send completions ASTs for locks that can now be
 474                          * granted. The only problem with doing this
 475                          * reprocessing here is that the completion ASTs for
 476                          * newly granted locks will be sent before the unlock
 477                          * completion is sent. It shouldn't be an issue. Also
 478                          * note that ldlm_process_flock_lock() will recurse,
 479                          * but only once because first_enq will be false from
 480                          * ldlm_reprocess_queue. */
 481                         if ((mode == LCK_NL) && overlaps) {
 482                                 CFS_LIST_HEAD(rpc_list);
 483                                 int rc;
 484 restart:
 485                                 ldlm_reprocess_queue(res, &res->lr_waiting,
 486                                                      &rpc_list);
 487
 488                                 unlock_res_and_lock(req);
 489                                 rc = ldlm_run_ast_work(ns, &rpc_list,
 490                                                        LDLM_WORK_CP_AST);
 491                                 lock_res_and_lock(req);
 492                                 if (rc == -ERESTART)
 493                                         GOTO(restart, -ERESTART);
 494                        }
 495                 } else {
 496                         LASSERT(req->l_completion_ast);
 497                         ldlm_add_ast_work_item(req, NULL, work_list);
 498                 }
 499 #else /* !HAVE_SERVER_SUPPORT */
 500                 /* The only one possible case for client-side calls flock
 501                  * policy function is ldlm_flock_completion_ast inside which
 502                  * carries LDLM_FL_WAIT_NOREPROC flag. */
 503                 CERROR("Illegal parameter for client-side-only module.\n");
 504                 LBUG();
 505 #endif /* HAVE_SERVER_SUPPORT */
 506         }
 507
 508         /* In case we're reprocessing the requested lock we can't destroy
 509          * it until after calling ldlm_ast_work_item() above so that lawi()
 510          * can bump the reference count on req. Otherwise req could be freed
 511          * before the completion AST can be sent.  */
 512         if (added)
 513                 ldlm_flock_destroy(req, mode, *flags);
 514
 515         ldlm_resource_dump(D_INFO, res);
 516         RETURN(LDLM_ITER_CONTINUE);
 517 }
 518
 519 struct ldlm_flock_wait_data {
 520         struct ldlm_lock *fwd_lock;
 521         int               fwd_generation;
 522 };
 523
 524 static void
 525 ldlm_flock_interrupted_wait(void *data)
 526 {
 527         struct ldlm_lock *lock;
 528         ENTRY;
 529
 530         lock = ((struct ldlm_flock_wait_data *)data)->fwd_lock;
 531
 532         /* take lock off the deadlock detection waitq. */
 533         ldlm_flock_blocking_unlink(lock);
 534
 535         /* client side - set flag to prevent lock from being put on lru list */
 536         lock_res_and_lock(lock);
 537         lock->l_flags |= LDLM_FL_CBPENDING;
 538         unlock_res_and_lock(lock);
 539
 540         EXIT;
 541 }
 542
 543 /**
 544  * Flock completion calback function.
 545  *
 546  * \param lock [in,out]: A lock to be handled
 547  * \param flags    [in]: flags
 548  * \param *data    [in]: ldlm_work_cp_ast_lock() will use ldlm_cb_set_arg
 549  *
 550  * \retval 0    : success
 551  * \retval <0   : failure
 552  */
 553 int
 554 ldlm_flock_completion_ast(struct ldlm_lock *lock, int flags, void *data)
 555 {
 556         cfs_flock_t                    *getlk = lock->l_ast_data;
 557         struct obd_device              *obd;
 558         struct obd_import              *imp = NULL;
 559         struct ldlm_flock_wait_data     fwd;
 560         struct l_wait_info              lwi;
 561         ldlm_error_t                    err;
 562         int                             rc = 0;
 563         ENTRY;
 564
 565         CDEBUG(D_DLMTRACE, "flags: 0x%x data: %p getlk: %p\n",
 566                flags, data, getlk);
 567
 568         /* Import invalidation. We need to actually release the lock
 569          * references being held, so that it can go away. No point in
 570          * holding the lock even if app still believes it has it, since
 571          * server already dropped it anyway. Only for granted locks too. */
 572         if ((lock->l_flags & (LDLM_FL_FAILED|LDLM_FL_LOCAL_ONLY)) ==
 573             (LDLM_FL_FAILED|LDLM_FL_LOCAL_ONLY)) {
 574                 if (lock->l_req_mode == lock->l_granted_mode &&
 575                     lock->l_granted_mode != LCK_NL &&
 576                     NULL == data)
 577                         ldlm_lock_decref_internal(lock, lock->l_req_mode);
 578
 579                 /* Need to wake up the waiter if we were evicted */
 580                 cfs_waitq_signal(&lock->l_waitq);
 581                 RETURN(0);
 582         }
 583
 584         LASSERT(flags != LDLM_FL_WAIT_NOREPROC);
 585
 586         if (!(flags & (LDLM_FL_BLOCK_WAIT | LDLM_FL_BLOCK_GRANTED |
 587                        LDLM_FL_BLOCK_CONV))) {
 588                 if (NULL == data)
 589                         /* mds granted the lock in the reply */
 590                         goto granted;
 591                 /* CP AST RPC: lock get granted, wake it up */
 592                 cfs_waitq_signal(&lock->l_waitq);
 593                 RETURN(0);
 594         }
 595
 596         LDLM_DEBUG(lock, "client-side enqueue returned a blocked lock, "
 597                    "sleeping");
 598         fwd.fwd_lock = lock;
 599         obd = class_exp2obd(lock->l_conn_export);
 600
 601         /* if this is a local lock, there is no import */
 602         if (NULL != obd)
 603                 imp = obd->u.cli.cl_import;
 604
 605         if (NULL != imp) {
 606                 cfs_spin_lock(&imp->imp_lock);
 607                 fwd.fwd_generation = imp->imp_generation;
 608                 cfs_spin_unlock(&imp->imp_lock);
 609         }
 610
 611         lwi = LWI_TIMEOUT_INTR(0, NULL, ldlm_flock_interrupted_wait, &fwd);
 612
 613         /* Go to sleep until the lock is granted. */
 614         rc = l_wait_event(lock->l_waitq, is_granted_or_cancelled(lock), &lwi);
 615
 616         if (rc) {
 617                 LDLM_DEBUG(lock, "client-side enqueue waking up: failed (%d)",
 618                            rc);
 619                 RETURN(rc);
 620         }
 621
 622 granted:
 623         OBD_FAIL_TIMEOUT(OBD_FAIL_LDLM_CP_CB_WAIT, 10);
 624
 625         if (lock->l_destroyed) {
 626                 LDLM_DEBUG(lock, "client-side enqueue waking up: destroyed");
 627                 RETURN(0);
 628         }
 629
 630         if (lock->l_flags & LDLM_FL_FAILED) {
 631                 LDLM_DEBUG(lock, "client-side enqueue waking up: failed");
 632                 RETURN(-EIO);
 633         }
 634
 635         if (rc) {
 636                 LDLM_DEBUG(lock, "client-side enqueue waking up: failed (%d)",
 637                            rc);
 638                 RETURN(rc);
 639         }
 640
 641         LDLM_DEBUG(lock, "client-side enqueue granted");
 642
 643         /* take lock off the deadlock detection waitq. */
 644         ldlm_flock_blocking_unlink(lock);
 645
 646         lock_res_and_lock(lock);
 647         /* ldlm_lock_enqueue() has already placed lock on the granted list. */
 648         cfs_list_del_init(&lock->l_res_link);
 649
 650         if (flags & LDLM_FL_TEST_LOCK) {
 651                 /* fcntl(F_GETLK) request */
 652                 /* The old mode was saved in getlk->fl_type so that if the mode
 653                  * in the lock changes we can decref the appropriate refcount.*/
 654                 ldlm_flock_destroy(lock, cfs_flock_type(getlk),
 655                                    LDLM_FL_WAIT_NOREPROC);
 656                 switch (lock->l_granted_mode) {
 657                 case LCK_PR:
 658                         cfs_flock_set_type(getlk, F_RDLCK);
 659                         break;
 660                 case LCK_PW:
 661                         cfs_flock_set_type(getlk, F_WRLCK);
 662                         break;
 663                 default:
 664                         cfs_flock_set_type(getlk, F_UNLCK);
 665                 }
 666                 cfs_flock_set_pid(getlk,
 667                                   (pid_t)lock->l_policy_data.l_flock.pid);
 668                 cfs_flock_set_start(getlk,
 669                                     (loff_t)lock->l_policy_data.l_flock.start);
 670                 cfs_flock_set_end(getlk,
 671                                   (loff_t)lock->l_policy_data.l_flock.end);
 672         } else {
 673                 int noreproc = LDLM_FL_WAIT_NOREPROC;
 674
 675                 /* We need to reprocess the lock to do merges or splits
 676                  * with existing locks owned by this process. */
 677                 ldlm_process_flock_lock(lock, &noreproc, 1, &err, NULL);
 678         }
 679         unlock_res_and_lock(lock);
 680         RETURN(0);
 681 }
 682 EXPORT_SYMBOL(ldlm_flock_completion_ast);
 683
 684 int ldlm_flock_blocking_ast(struct ldlm_lock *lock, struct ldlm_lock_desc *desc,
 685                             void *data, int flag)
 686 {
 687         ENTRY;
 688
 689         LASSERT(lock);
 690         LASSERT(flag == LDLM_CB_CANCELING);
 691
 692         /* take lock off the deadlock detection waitq. */
 693         ldlm_flock_blocking_unlink(lock);
 694         RETURN(0);
 695 }
 696
 697 void ldlm_flock_policy_wire18_to_local(const ldlm_wire_policy_data_t *wpolicy,
 698                                        ldlm_policy_data_t *lpolicy)
 699 {
 700         memset(lpolicy, 0, sizeof(*lpolicy));
 701         lpolicy->l_flock.start = wpolicy->l_flock.lfw_start;
 702         lpolicy->l_flock.end = wpolicy->l_flock.lfw_end;
 703         lpolicy->l_flock.pid = wpolicy->l_flock.lfw_pid;
 704         /* Compat code, old clients had no idea about owner field and
 705          * relied solely on pid for ownership. Introduced in LU-104, 2.1,
 706          * April 2011 */
 707         lpolicy->l_flock.owner = wpolicy->l_flock.lfw_pid;
 708 }
 709
 710
 711 void ldlm_flock_policy_wire21_to_local(const ldlm_wire_policy_data_t *wpolicy,
 712                                        ldlm_policy_data_t *lpolicy)
 713 {
 714         memset(lpolicy, 0, sizeof(*lpolicy));
 715         lpolicy->l_flock.start = wpolicy->l_flock.lfw_start;
 716         lpolicy->l_flock.end = wpolicy->l_flock.lfw_end;
 717         lpolicy->l_flock.pid = wpolicy->l_flock.lfw_pid;
 718         lpolicy->l_flock.owner = wpolicy->l_flock.lfw_owner;
 719 }
 720
 721 void ldlm_flock_policy_local_to_wire(const ldlm_policy_data_t *lpolicy,
 722                                      ldlm_wire_policy_data_t *wpolicy)
 723 {
 724         memset(wpolicy, 0, sizeof(*wpolicy));
 725         wpolicy->l_flock.lfw_start = lpolicy->l_flock.start;
 726         wpolicy->l_flock.lfw_end = lpolicy->l_flock.end;
 727         wpolicy->l_flock.lfw_pid = lpolicy->l_flock.pid;
 728         wpolicy->l_flock.lfw_owner = lpolicy->l_flock.owner;
 729 }