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
  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) 2003 Hewlett-Packard Development Company LP.
  30  * Developed under the sponsorship of the US Government under
  31  * Subcontract No. B514193
  32  *
  33  * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
  34  * Use is subject to license terms.
  35  *
  36  * Copyright (c) 2010, 2011, Whamcloud, Inc.
  37  */
  38 /*
  39  * This file is part of Lustre, http://www.lustre.org/
  40  * Lustre is a trademark of Sun Microsystems, Inc.
  41  */
  42
  43 #define DEBUG_SUBSYSTEM S_LDLM
  44
  45 #ifdef __KERNEL__
  46 #include <lustre_dlm.h>
  47 #include <obd_support.h>
  48 #include <obd_class.h>
  49 #include <lustre_lib.h>
  50 #include <libcfs/list.h>
  51 #else
  52 #include <liblustre.h>
  53 #include <obd_class.h>
  54 #endif
  55
  56 #include "ldlm_internal.h"
  57
  58 #define l_flock_waitq   l_lru
  59
  60 int ldlm_flock_blocking_ast(struct ldlm_lock *lock, struct ldlm_lock_desc *desc,
  61                             void *data, int flag);
  62
  63 /**
  64  * list_for_remaining_safe - iterate over the remaining entries in a list
  65  *              and safeguard against removal of a list entry.
  66  * \param pos   the &struct list_head to use as a loop counter. pos MUST
  67  *              have been initialized prior to using it in this macro.
  68  * \param n     another &struct list_head to use as temporary storage
  69  * \param head  the head for your list.
  70  */
  71 #define list_for_remaining_safe(pos, n, head) \
  72         for (n = pos->next; pos != (head); pos = n, n = pos->next)
  73
  74 static inline int
  75 ldlm_same_flock_owner(struct ldlm_lock *lock, struct ldlm_lock *new)
  76 {
  77         return((new->l_policy_data.l_flock.owner ==
  78                 lock->l_policy_data.l_flock.owner) &&
  79                (new->l_export == lock->l_export));
  80 }
  81
  82 static inline int
  83 ldlm_flocks_overlap(struct ldlm_lock *lock, struct ldlm_lock *new)
  84 {
  85         return((new->l_policy_data.l_flock.start <=
  86                 lock->l_policy_data.l_flock.end) &&
  87                (new->l_policy_data.l_flock.end >=
  88                 lock->l_policy_data.l_flock.start));
  89 }
  90
  91 static inline void ldlm_flock_blocking_link(struct ldlm_lock *req,
  92                                             struct ldlm_lock *lock)
  93 {
  94         /* For server only */
  95         if (req->l_export == NULL)
  96                 return;
  97
  98         LASSERT(cfs_list_empty(&req->l_flock_waitq));
  99         cfs_write_lock(&req->l_export->exp_flock_wait_lock);
 100
 101         req->l_policy_data.l_flock.blocking_owner =
 102                 lock->l_policy_data.l_flock.owner;
 103         req->l_policy_data.l_flock.blocking_export =
 104                 class_export_get(lock->l_export);
 105
 106         cfs_list_add_tail(&req->l_flock_waitq,
 107                           &req->l_export->exp_flock_wait_list);
 108         cfs_write_unlock(&req->l_export->exp_flock_wait_lock);
 109 }
 110
 111 static inline void ldlm_flock_blocking_unlink(struct ldlm_lock *req)
 112 {
 113         /* For server only */
 114         if (req->l_export == NULL)
 115                 return;
 116
 117         cfs_write_lock(&req->l_export->exp_flock_wait_lock);
 118         if (!cfs_list_empty(&req->l_flock_waitq)) {
 119                 cfs_list_del_init(&req->l_flock_waitq);
 120
 121                 class_export_put(req->l_policy_data.l_flock.blocking_export);
 122                 req->l_policy_data.l_flock.blocking_owner = 0;
 123                 req->l_policy_data.l_flock.blocking_export = NULL;
 124         }
 125         cfs_write_unlock(&req->l_export->exp_flock_wait_lock);
 126 }
 127
 128 static inline void
 129 ldlm_flock_destroy(struct ldlm_lock *lock, ldlm_mode_t mode, int flags)
 130 {
 131         ENTRY;
 132
 133         LDLM_DEBUG(lock, "ldlm_flock_destroy(mode: %d, flags: 0x%x)",
 134                    mode, flags);
 135
 136         /* Safe to not lock here, since it should be empty anyway */
 137         LASSERT(cfs_list_empty(&lock->l_flock_waitq));
 138
 139         cfs_list_del_init(&lock->l_res_link);
 140         if (flags == LDLM_FL_WAIT_NOREPROC &&
 141             !(lock->l_flags & LDLM_FL_FAILED)) {
 142                 /* client side - set a flag to prevent sending a CANCEL */
 143                 lock->l_flags |= LDLM_FL_LOCAL_ONLY | LDLM_FL_CBPENDING;
 144
 145                 /* when reaching here, it is under lock_res_and_lock(). Thus,
 146                    need call the nolock version of ldlm_lock_decref_internal*/
 147                 ldlm_lock_decref_internal_nolock(lock, mode);
 148         }
 149
 150         ldlm_lock_destroy_nolock(lock);
 151         EXIT;
 152 }
 153
 154 static int
 155 ldlm_flock_deadlock(struct ldlm_lock *req, struct ldlm_lock *bl_lock)
 156 {
 157         struct obd_export *req_exp = req->l_export;
 158         struct obd_export *bl_exp = bl_lock->l_export;
 159         struct obd_export *bl_exp_new;
 160         __u64 req_owner = req->l_policy_data.l_flock.owner;
 161         __u64 bl_owner = bl_lock->l_policy_data.l_flock.owner;
 162         struct ldlm_lock *lock;
 163
 164         /* For server only */
 165         if (req_exp == NULL)
 166                 return 0;
 167
 168         class_export_get(bl_exp);
 169 restart:
 170         cfs_read_lock(&bl_exp->exp_flock_wait_lock);
 171         cfs_list_for_each_entry(lock, &bl_exp->exp_flock_wait_list,
 172                                 l_flock_waitq) {
 173                 struct ldlm_flock *flock = &lock->l_policy_data.l_flock;
 174
 175                 /* want to find something from same client and same process */
 176                 if (flock->owner != bl_owner)
 177                         continue;
 178
 179                 bl_owner = flock->blocking_owner;
 180                 bl_exp_new = class_export_get(flock->blocking_export);
 181                 cfs_read_unlock(&bl_exp->exp_flock_wait_lock);
 182                 class_export_put(bl_exp);
 183                 bl_exp = bl_exp_new;
 184
 185                 if (bl_owner == req_owner && bl_exp == req_exp) {
 186                         class_export_put(bl_exp);
 187                         return 1;
 188                 }
 189
 190                 goto restart;
 191         }
 192         cfs_read_unlock(&bl_exp->exp_flock_wait_lock);
 193         class_export_put(bl_exp);
 194
 195         return 0;
 196 }
 197
 198 int
 199 ldlm_process_flock_lock(struct ldlm_lock *req, int *flags, int first_enq,
 200                         ldlm_error_t *err, cfs_list_t *work_list)
 201 {
 202         struct ldlm_resource *res = req->l_resource;
 203         struct ldlm_namespace *ns = ldlm_res_to_ns(res);
 204         cfs_list_t *tmp;
 205         cfs_list_t *ownlocks = NULL;
 206         struct ldlm_lock *lock = NULL;
 207         struct ldlm_lock *new = req;
 208         struct ldlm_lock *new2 = NULL;
 209         ldlm_mode_t mode = req->l_req_mode;
 210         int local = ns_is_client(ns);
 211         int added = (mode == LCK_NL);
 212         int overlaps = 0;
 213         int splitted = 0;
 214         const struct ldlm_callback_suite null_cbs = { NULL };
 215         ENTRY;
 216
 217         CDEBUG(D_DLMTRACE, "flags %#x owner "LPU64" pid %u mode %u start "LPU64
 218                " end "LPU64"\n", *flags, new->l_policy_data.l_flock.owner,
 219                new->l_policy_data.l_flock.pid, mode,
 220                req->l_policy_data.l_flock.start,
 221                req->l_policy_data.l_flock.end);
 222
 223         *err = ELDLM_OK;
 224
 225         if (local) {
 226                 /* No blocking ASTs are sent to the clients for
 227                  * Posix file & record locks */
 228                 req->l_blocking_ast = NULL;
 229         } else {
 230                 /* Called on the server for lock cancels. */
 231                 req->l_blocking_ast = ldlm_flock_blocking_ast;
 232         }
 233
 234 reprocess:
 235         if ((*flags == LDLM_FL_WAIT_NOREPROC) || (mode == LCK_NL)) {
 236                 /* This loop determines where this processes locks start
 237                  * in the resource lr_granted list. */
 238                 cfs_list_for_each(tmp, &res->lr_granted) {
 239                         lock = cfs_list_entry(tmp, struct ldlm_lock,
 240                                               l_res_link);
 241                         if (ldlm_same_flock_owner(lock, req)) {
 242                                 ownlocks = tmp;
 243                                 break;
 244                         }
 245                 }
 246         } else {
 247                 lockmode_verify(mode);
 248
 249                 /* This loop determines if there are existing locks
 250                  * that conflict with the new lock request. */
 251                 cfs_list_for_each(tmp, &res->lr_granted) {
 252                         lock = cfs_list_entry(tmp, struct ldlm_lock,
 253                                               l_res_link);
 254
 255                         if (ldlm_same_flock_owner(lock, req)) {
 256                                 if (!ownlocks)
 257                                         ownlocks = tmp;
 258                                 continue;
 259                         }
 260
 261                         /* locks are compatible, overlap doesn't matter */
 262                         if (lockmode_compat(lock->l_granted_mode, mode))
 263                                 continue;
 264
 265                         if (!ldlm_flocks_overlap(lock, req))
 266                                 continue;
 267
 268                         if (!first_enq)
 269                                 RETURN(LDLM_ITER_CONTINUE);
 270
 271                         if (*flags & LDLM_FL_BLOCK_NOWAIT) {
 272                                 ldlm_flock_destroy(req, mode, *flags);
 273                                 *err = -EAGAIN;
 274                                 RETURN(LDLM_ITER_STOP);
 275                         }
 276
 277                         if (*flags & LDLM_FL_TEST_LOCK) {
 278                                 ldlm_flock_destroy(req, mode, *flags);
 279                                 req->l_req_mode = lock->l_granted_mode;
 280                                 req->l_policy_data.l_flock.pid =
 281                                         lock->l_policy_data.l_flock.pid;
 282                                 req->l_policy_data.l_flock.start =
 283                                         lock->l_policy_data.l_flock.start;
 284                                 req->l_policy_data.l_flock.end =
 285                                         lock->l_policy_data.l_flock.end;
 286                                 *flags |= LDLM_FL_LOCK_CHANGED;
 287                                 RETURN(LDLM_ITER_STOP);
 288                         }
 289
 290                         if (ldlm_flock_deadlock(req, lock)) {
 291                                 ldlm_flock_destroy(req, mode, *flags);
 292                                 *err = -EDEADLK;
 293                                 RETURN(LDLM_ITER_STOP);
 294                         }
 295
 296
 297                         ldlm_flock_blocking_link(req, lock);
 298                         ldlm_resource_add_lock(res, &res->lr_waiting, req);
 299                         *flags |= LDLM_FL_BLOCK_GRANTED;
 300                         RETURN(LDLM_ITER_STOP);
 301                 }
 302         }
 303
 304         if (*flags & LDLM_FL_TEST_LOCK) {
 305                 ldlm_flock_destroy(req, mode, *flags);
 306                 req->l_req_mode = LCK_NL;
 307                 *flags |= LDLM_FL_LOCK_CHANGED;
 308                 RETURN(LDLM_ITER_STOP);
 309         }
 310
 311         /* In case we had slept on this lock request take it off of the
 312          * deadlock detection waitq. */
 313         ldlm_flock_blocking_unlink(req);
 314
 315         /* Scan the locks owned by this process that overlap this request.
 316          * We may have to merge or split existing locks. */
 317
 318         if (!ownlocks)
 319                 ownlocks = &res->lr_granted;
 320
 321         list_for_remaining_safe(ownlocks, tmp, &res->lr_granted) {
 322                 lock = cfs_list_entry(ownlocks, struct ldlm_lock, l_res_link);
 323
 324                 if (!ldlm_same_flock_owner(lock, new))
 325                         break;
 326
 327                 if (lock->l_granted_mode == mode) {
 328                         /* If the modes are the same then we need to process
 329                          * locks that overlap OR adjoin the new lock. The extra
 330                          * logic condition is necessary to deal with arithmetic
 331                          * overflow and underflow. */
 332                         if ((new->l_policy_data.l_flock.start >
 333                              (lock->l_policy_data.l_flock.end + 1))
 334                             && (lock->l_policy_data.l_flock.end !=
 335                                 OBD_OBJECT_EOF))
 336                                 continue;
 337
 338                         if ((new->l_policy_data.l_flock.end <
 339                              (lock->l_policy_data.l_flock.start - 1))
 340                             && (lock->l_policy_data.l_flock.start != 0))
 341                                 break;
 342
 343                         if (new->l_policy_data.l_flock.start <
 344                             lock->l_policy_data.l_flock.start) {
 345                                 lock->l_policy_data.l_flock.start =
 346                                         new->l_policy_data.l_flock.start;
 347                         } else {
 348                                 new->l_policy_data.l_flock.start =
 349                                         lock->l_policy_data.l_flock.start;
 350                         }
 351
 352                         if (new->l_policy_data.l_flock.end >
 353                             lock->l_policy_data.l_flock.end) {
 354                                 lock->l_policy_data.l_flock.end =
 355                                         new->l_policy_data.l_flock.end;
 356                         } else {
 357                                 new->l_policy_data.l_flock.end =
 358                                         lock->l_policy_data.l_flock.end;
 359                         }
 360
 361                         if (added) {
 362                                 ldlm_flock_destroy(lock, mode, *flags);
 363                         } else {
 364                                 new = lock;
 365                                 added = 1;
 366                         }
 367                         continue;
 368                 }
 369
 370                 if (new->l_policy_data.l_flock.start >
 371                     lock->l_policy_data.l_flock.end)
 372                         continue;
 373
 374                 if (new->l_policy_data.l_flock.end <
 375                     lock->l_policy_data.l_flock.start)
 376                         break;
 377
 378                 ++overlaps;
 379
 380                 if (new->l_policy_data.l_flock.start <=
 381                     lock->l_policy_data.l_flock.start) {
 382                         if (new->l_policy_data.l_flock.end <
 383                             lock->l_policy_data.l_flock.end) {
 384                                 lock->l_policy_data.l_flock.start =
 385                                         new->l_policy_data.l_flock.end + 1;
 386                                 break;
 387                         }
 388                         ldlm_flock_destroy(lock, lock->l_req_mode, *flags);
 389                         continue;
 390                 }
 391                 if (new->l_policy_data.l_flock.end >=
 392                     lock->l_policy_data.l_flock.end) {
 393                         lock->l_policy_data.l_flock.end =
 394                                 new->l_policy_data.l_flock.start - 1;
 395                         continue;
 396                 }
 397
 398                 /* split the existing lock into two locks */
 399
 400                 /* if this is an F_UNLCK operation then we could avoid
 401                  * allocating a new lock and use the req lock passed in
 402                  * with the request but this would complicate the reply
 403                  * processing since updates to req get reflected in the
 404                  * reply. The client side replays the lock request so
 405                  * it must see the original lock data in the reply. */
 406
 407                 /* XXX - if ldlm_lock_new() can sleep we should
 408                  * release the lr_lock, allocate the new lock,
 409                  * and restart processing this lock. */
 410                 if (!new2) {
 411                         unlock_res_and_lock(req);
 412                          new2 = ldlm_lock_create(ns, &res->lr_name, LDLM_FLOCK,
 413                                         lock->l_granted_mode, &null_cbs,
 414                                         NULL, 0);
 415                         lock_res_and_lock(req);
 416                         if (!new2) {
 417                                 ldlm_flock_destroy(req, lock->l_granted_mode,
 418                                                    *flags);
 419                                 *err = -ENOLCK;
 420                                 RETURN(LDLM_ITER_STOP);
 421                         }
 422                         goto reprocess;
 423                 }
 424
 425                 splitted = 1;
 426
 427                 new2->l_granted_mode = lock->l_granted_mode;
 428                 new2->l_policy_data.l_flock.pid =
 429                         new->l_policy_data.l_flock.pid;
 430                 new2->l_policy_data.l_flock.owner =
 431                         new->l_policy_data.l_flock.owner;
 432                 new2->l_policy_data.l_flock.start =
 433                         lock->l_policy_data.l_flock.start;
 434                 new2->l_policy_data.l_flock.end =
 435                         new->l_policy_data.l_flock.start - 1;
 436                 lock->l_policy_data.l_flock.start =
 437                         new->l_policy_data.l_flock.end + 1;
 438                 new2->l_conn_export = lock->l_conn_export;
 439                 if (lock->l_export != NULL) {
 440                         new2->l_export = class_export_lock_get(lock->l_export, new2);
 441                         if (new2->l_export->exp_lock_hash &&
 442                             cfs_hlist_unhashed(&new2->l_exp_hash))
 443                                 cfs_hash_add(new2->l_export->exp_lock_hash,
 444                                              &new2->l_remote_handle,
 445                                              &new2->l_exp_hash);
 446                 }
 447                 if (*flags == LDLM_FL_WAIT_NOREPROC)
 448                         ldlm_lock_addref_internal_nolock(new2,
 449                                                          lock->l_granted_mode);
 450
 451                 /* insert new2 at lock */
 452                 ldlm_resource_add_lock(res, ownlocks, new2);
 453                 LDLM_LOCK_RELEASE(new2);
 454                 break;
 455         }
 456
 457         /* if new2 is created but never used, destroy it*/
 458         if (splitted == 0 && new2 != NULL)
 459                 ldlm_lock_destroy_nolock(new2);
 460
 461         /* At this point we're granting the lock request. */
 462         req->l_granted_mode = req->l_req_mode;
 463
 464         /* Add req to the granted queue before calling ldlm_reprocess_all(). */
 465         if (!added) {
 466                 cfs_list_del_init(&req->l_res_link);
 467                 /* insert new lock before ownlocks in list. */
 468                 ldlm_resource_add_lock(res, ownlocks, req);
 469         }
 470
 471         if (*flags != LDLM_FL_WAIT_NOREPROC) {
 472 #ifdef HAVE_SERVER_SUPPORT
 473                 if (first_enq) {
 474                         /* If this is an unlock, reprocess the waitq and
 475                          * send completions ASTs for locks that can now be
 476                          * granted. The only problem with doing this
 477                          * reprocessing here is that the completion ASTs for
 478                          * newly granted locks will be sent before the unlock
 479                          * completion is sent. It shouldn't be an issue. Also
 480                          * note that ldlm_process_flock_lock() will recurse,
 481                          * but only once because first_enq will be false from
 482                          * ldlm_reprocess_queue. */
 483                         if ((mode == LCK_NL) && overlaps) {
 484                                 CFS_LIST_HEAD(rpc_list);
 485                                 int rc;
 486 restart:
 487                                 ldlm_reprocess_queue(res, &res->lr_waiting,
 488                                                      &rpc_list);
 489
 490                                 unlock_res_and_lock(req);
 491                                 rc = ldlm_run_ast_work(ns, &rpc_list,
 492                                                        LDLM_WORK_CP_AST);
 493                                 lock_res_and_lock(req);
 494                                 if (rc == -ERESTART)
 495                                         GOTO(restart, -ERESTART);
 496                        }
 497                 } else {
 498                         LASSERT(req->l_completion_ast);
 499                         ldlm_add_ast_work_item(req, NULL, work_list);
 500                 }
 501 #else /* !HAVE_SERVER_SUPPORT */
 502                 /* The only one possible case for client-side calls flock
 503                  * policy function is ldlm_flock_completion_ast inside which
 504                  * carries LDLM_FL_WAIT_NOREPROC flag. */
 505                 CERROR("Illegal parameter for client-side-only module.\n");
 506                 LBUG();
 507 #endif /* HAVE_SERVER_SUPPORT */
 508         }
 509
 510         /* In case we're reprocessing the requested lock we can't destroy
 511          * it until after calling ldlm_ast_work_item() above so that lawi()
 512          * can bump the reference count on req. Otherwise req could be freed
 513          * before the completion AST can be sent.  */
 514         if (added)
 515                 ldlm_flock_destroy(req, mode, *flags);
 516
 517         ldlm_resource_dump(D_INFO, res);
 518         RETURN(LDLM_ITER_CONTINUE);
 519 }
 520
 521 struct ldlm_flock_wait_data {
 522         struct ldlm_lock *fwd_lock;
 523         int               fwd_generation;
 524 };
 525
 526 static void
 527 ldlm_flock_interrupted_wait(void *data)
 528 {
 529         struct ldlm_lock *lock;
 530         ENTRY;
 531
 532         lock = ((struct ldlm_flock_wait_data *)data)->fwd_lock;
 533
 534         /* take lock off the deadlock detection waitq. */
 535         ldlm_flock_blocking_unlink(lock);
 536
 537         /* client side - set flag to prevent lock from being put on lru list */
 538         lock_res_and_lock(lock);
 539         lock->l_flags |= LDLM_FL_CBPENDING;
 540         unlock_res_and_lock(lock);
 541
 542         EXIT;
 543 }
 544
 545 /**
 546  * Flock completion calback function.
 547  *
 548  * \param lock [in,out]: A lock to be handled
 549  * \param flags    [in]: flags
 550  * \param *data    [in]: ldlm_work_cp_ast_lock() will use ldlm_cb_set_arg
 551  *
 552  * \retval 0    : success
 553  * \retval <0   : failure
 554  */
 555 int
 556 ldlm_flock_completion_ast(struct ldlm_lock *lock, int flags, void *data)
 557 {
 558         cfs_flock_t                    *getlk = lock->l_ast_data;
 559         struct obd_device              *obd;
 560         struct obd_import              *imp = NULL;
 561         struct ldlm_flock_wait_data     fwd;
 562         struct l_wait_info              lwi;
 563         ldlm_error_t                    err;
 564         int                             rc = 0;
 565         ENTRY;
 566
 567         CDEBUG(D_DLMTRACE, "flags: 0x%x data: %p getlk: %p\n",
 568                flags, data, getlk);
 569
 570         /* Import invalidation. We need to actually release the lock
 571          * references being held, so that it can go away. No point in
 572          * holding the lock even if app still believes it has it, since
 573          * server already dropped it anyway. Only for granted locks too. */
 574         if ((lock->l_flags & (LDLM_FL_FAILED|LDLM_FL_LOCAL_ONLY)) ==
 575             (LDLM_FL_FAILED|LDLM_FL_LOCAL_ONLY)) {
 576                 if (lock->l_req_mode == lock->l_granted_mode &&
 577                     lock->l_granted_mode != LCK_NL &&
 578                     NULL == data)
 579                         ldlm_lock_decref_internal(lock, lock->l_req_mode);
 580
 581                 /* Need to wake up the waiter if we were evicted */
 582                 cfs_waitq_signal(&lock->l_waitq);
 583                 RETURN(0);
 584         }
 585
 586         LASSERT(flags != LDLM_FL_WAIT_NOREPROC);
 587
 588         if (!(flags & (LDLM_FL_BLOCK_WAIT | LDLM_FL_BLOCK_GRANTED |
 589                        LDLM_FL_BLOCK_CONV))) {
 590                 if (NULL == data)
 591                         /* mds granted the lock in the reply */
 592                         goto granted;
 593                 /* CP AST RPC: lock get granted, wake it up */
 594                 cfs_waitq_signal(&lock->l_waitq);
 595                 RETURN(0);
 596         }
 597
 598         LDLM_DEBUG(lock, "client-side enqueue returned a blocked lock, "
 599                    "sleeping");
 600         fwd.fwd_lock = lock;
 601         obd = class_exp2obd(lock->l_conn_export);
 602
 603         /* if this is a local lock, there is no import */
 604         if (NULL != obd)
 605                 imp = obd->u.cli.cl_import;
 606
 607         if (NULL != imp) {
 608                 cfs_spin_lock(&imp->imp_lock);
 609                 fwd.fwd_generation = imp->imp_generation;
 610                 cfs_spin_unlock(&imp->imp_lock);
 611         }
 612
 613         lwi = LWI_TIMEOUT_INTR(0, NULL, ldlm_flock_interrupted_wait, &fwd);
 614
 615         /* Go to sleep until the lock is granted. */
 616         rc = l_wait_event(lock->l_waitq, is_granted_or_cancelled(lock), &lwi);
 617
 618         if (rc) {
 619                 LDLM_DEBUG(lock, "client-side enqueue waking up: failed (%d)",
 620                            rc);
 621                 RETURN(rc);
 622         }
 623
 624 granted:
 625         OBD_FAIL_TIMEOUT(OBD_FAIL_LDLM_CP_CB_WAIT, 10);
 626
 627         if (lock->l_destroyed) {
 628                 LDLM_DEBUG(lock, "client-side enqueue waking up: destroyed");
 629                 RETURN(0);
 630         }
 631
 632         if (lock->l_flags & LDLM_FL_FAILED) {
 633                 LDLM_DEBUG(lock, "client-side enqueue waking up: failed");
 634                 RETURN(-EIO);
 635         }
 636
 637         if (rc) {
 638                 LDLM_DEBUG(lock, "client-side enqueue waking up: failed (%d)",
 639                            rc);
 640                 RETURN(rc);
 641         }
 642
 643         LDLM_DEBUG(lock, "client-side enqueue granted");
 644
 645         /* take lock off the deadlock detection waitq. */
 646         ldlm_flock_blocking_unlink(lock);
 647
 648         lock_res_and_lock(lock);
 649         /* ldlm_lock_enqueue() has already placed lock on the granted list. */
 650         cfs_list_del_init(&lock->l_res_link);
 651
 652         if (flags & LDLM_FL_TEST_LOCK) {
 653                 /* fcntl(F_GETLK) request */
 654                 /* The old mode was saved in getlk->fl_type so that if the mode
 655                  * in the lock changes we can decref the appropriate refcount.*/
 656                 ldlm_flock_destroy(lock, cfs_flock_type(getlk),
 657                                    LDLM_FL_WAIT_NOREPROC);
 658                 switch (lock->l_granted_mode) {
 659                 case LCK_PR:
 660                         cfs_flock_set_type(getlk, F_RDLCK);
 661                         break;
 662                 case LCK_PW:
 663                         cfs_flock_set_type(getlk, F_WRLCK);
 664                         break;
 665                 default:
 666                         cfs_flock_set_type(getlk, F_UNLCK);
 667                 }
 668                 cfs_flock_set_pid(getlk,
 669                                   (pid_t)lock->l_policy_data.l_flock.pid);
 670                 cfs_flock_set_start(getlk,
 671                                     (loff_t)lock->l_policy_data.l_flock.start);
 672                 cfs_flock_set_end(getlk,
 673                                   (loff_t)lock->l_policy_data.l_flock.end);
 674         } else {
 675                 int noreproc = LDLM_FL_WAIT_NOREPROC;
 676
 677                 /* We need to reprocess the lock to do merges or splits
 678                  * with existing locks owned by this process. */
 679                 ldlm_process_flock_lock(lock, &noreproc, 1, &err, NULL);
 680         }
 681         unlock_res_and_lock(lock);
 682         RETURN(0);
 683 }
 684 EXPORT_SYMBOL(ldlm_flock_completion_ast);
 685
 686 int ldlm_flock_blocking_ast(struct ldlm_lock *lock, struct ldlm_lock_desc *desc,
 687                             void *data, int flag)
 688 {
 689         ENTRY;
 690
 691         LASSERT(lock);
 692         LASSERT(flag == LDLM_CB_CANCELING);
 693
 694         /* take lock off the deadlock detection waitq. */
 695         ldlm_flock_blocking_unlink(lock);
 696         RETURN(0);
 697 }
 698
 699 void ldlm_flock_policy_wire18_to_local(const ldlm_wire_policy_data_t *wpolicy,
 700                                        ldlm_policy_data_t *lpolicy)
 701 {
 702         memset(lpolicy, 0, sizeof(*lpolicy));
 703         lpolicy->l_flock.start = wpolicy->l_flock.lfw_start;
 704         lpolicy->l_flock.end = wpolicy->l_flock.lfw_end;
 705         lpolicy->l_flock.pid = wpolicy->l_flock.lfw_pid;
 706         /* Compat code, old clients had no idea about owner field and
 707          * relied solely on pid for ownership. Introduced in LU-104, 2.1,
 708          * April 2011 */
 709         lpolicy->l_flock.owner = wpolicy->l_flock.lfw_pid;
 710 }
 711
 712
 713 void ldlm_flock_policy_wire21_to_local(const ldlm_wire_policy_data_t *wpolicy,
 714                                        ldlm_policy_data_t *lpolicy)
 715 {
 716         memset(lpolicy, 0, sizeof(*lpolicy));
 717         lpolicy->l_flock.start = wpolicy->l_flock.lfw_start;
 718         lpolicy->l_flock.end = wpolicy->l_flock.lfw_end;
 719         lpolicy->l_flock.pid = wpolicy->l_flock.lfw_pid;
 720         lpolicy->l_flock.owner = wpolicy->l_flock.lfw_owner;
 721 }
 722
 723 void ldlm_flock_policy_local_to_wire(const ldlm_policy_data_t *lpolicy,
 724                                      ldlm_wire_policy_data_t *wpolicy)
 725 {
 726         memset(wpolicy, 0, sizeof(*wpolicy));
 727         wpolicy->l_flock.lfw_start = lpolicy->l_flock.start;
 728         wpolicy->l_flock.lfw_end = lpolicy->l_flock.end;
 729         wpolicy->l_flock.lfw_pid = lpolicy->l_flock.pid;
 730         wpolicy->l_flock.lfw_owner = lpolicy->l_flock.owner;
 731 }