1/* -*- mode: c; c-basic-offset: 8; -*- 2 * vim: noexpandtab sw=8 ts=8 sts=0: 3 * 4 * dlmlock.c 5 * 6 * underlying calls for lock creation 7 * 8 * Copyright (C) 2004 Oracle. All rights reserved. 9 * 10 * This program is free software; you can redistribute it and/or 11 * modify it under the terms of the GNU General Public 12 * License as published by the Free Software Foundation; either 13 * version 2 of the License, or (at your option) any later version. 14 * 15 * This program is distributed in the hope that it will be useful, 16 * but WITHOUT ANY WARRANTY; without even the implied warranty of 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 18 * General Public License for more details. 19 * 20 * You should have received a copy of the GNU General Public 21 * License along with this program; if not, write to the 22 * Free Software Foundation, Inc., 59 Temple Place - Suite 330, 23 * Boston, MA 021110-1307, USA. 24 * 25 */ 26 27 28#include <linux/module.h> 29#include <linux/fs.h> 30#include <linux/types.h> 31#include <linux/slab.h> 32#include <linux/highmem.h> 33#include <linux/init.h> 34#include <linux/sysctl.h> 35#include <linux/random.h> 36#include <linux/blkdev.h> 37#include <linux/socket.h> 38#include <linux/inet.h> 39#include <linux/spinlock.h> 40#include <linux/delay.h> 41 42 43#include "cluster/heartbeat.h" 44#include "cluster/nodemanager.h" 45#include "cluster/tcp.h" 46 47#include "dlmapi.h" 48#include "dlmcommon.h" 49 50#include "dlmconvert.h" 51 52#define MLOG_MASK_PREFIX ML_DLM 53#include "cluster/masklog.h" 54 55static struct kmem_cache *dlm_lock_cache; 56 57static DEFINE_SPINLOCK(dlm_cookie_lock); 58static u64 dlm_next_cookie = 1; 59 60static enum dlm_status dlm_send_remote_lock_request(struct dlm_ctxt *dlm, 61 struct dlm_lock_resource *res, 62 struct dlm_lock *lock, int flags); 63static void dlm_init_lock(struct dlm_lock *newlock, int type, 64 u8 node, u64 cookie); 65static void dlm_lock_release(struct kref *kref); 66static void dlm_lock_detach_lockres(struct dlm_lock *lock); 67 68int dlm_init_lock_cache(void) 69{ 70 dlm_lock_cache = kmem_cache_create("o2dlm_lock", 71 sizeof(struct dlm_lock), 72 0, SLAB_HWCACHE_ALIGN, NULL); 73 if (dlm_lock_cache == NULL) 74 return -ENOMEM; 75 return 0; 76} 77 78void dlm_destroy_lock_cache(void) 79{ 80 if (dlm_lock_cache) 81 kmem_cache_destroy(dlm_lock_cache); 82} 83 84/* Tell us whether we can grant a new lock request. 85 * locking: 86 * caller needs: res->spinlock 87 * taken: none 88 * held on exit: none 89 * returns: 1 if the lock can be granted, 0 otherwise. 90 */ 91static int dlm_can_grant_new_lock(struct dlm_lock_resource *res, 92 struct dlm_lock *lock) 93{ 94 struct dlm_lock *tmplock; 95 96 list_for_each_entry(tmplock, &res->granted, list) { 97 if (!dlm_lock_compatible(tmplock->ml.type, lock->ml.type)) 98 return 0; 99 } 100 101 list_for_each_entry(tmplock, &res->converting, list) { 102 if (!dlm_lock_compatible(tmplock->ml.type, lock->ml.type)) 103 return 0; 104 if (!dlm_lock_compatible(tmplock->ml.convert_type, 105 lock->ml.type)) 106 return 0; 107 } 108 109 return 1; 110} 111 112/* performs lock creation at the lockres master site 113 * locking: 114 * caller needs: none 115 * taken: takes and drops res->spinlock 116 * held on exit: none 117 * returns: DLM_NORMAL, DLM_NOTQUEUED 118 */ 119static enum dlm_status dlmlock_master(struct dlm_ctxt *dlm, 120 struct dlm_lock_resource *res, 121 struct dlm_lock *lock, int flags) 122{ 123 int call_ast = 0, kick_thread = 0; 124 enum dlm_status status = DLM_NORMAL; 125 126 mlog(0, "type=%d\n", lock->ml.type); 127 128 spin_lock(&res->spinlock); 129 /* if called from dlm_create_lock_handler, need to 130 * ensure it will not sleep in dlm_wait_on_lockres */ 131 status = __dlm_lockres_state_to_status(res); 132 if (status != DLM_NORMAL && 133 lock->ml.node != dlm->node_num) { 134 /* erf. state changed after lock was dropped. */ 135 spin_unlock(&res->spinlock); 136 dlm_error(status); 137 return status; 138 } 139 __dlm_wait_on_lockres(res); 140 __dlm_lockres_reserve_ast(res); 141 142 if (dlm_can_grant_new_lock(res, lock)) { 143 mlog(0, "I can grant this lock right away\n"); 144 /* got it right away */ 145 lock->lksb->status = DLM_NORMAL; 146 status = DLM_NORMAL; 147 dlm_lock_get(lock); 148 list_add_tail(&lock->list, &res->granted); 149 150 /* for the recovery lock, we can't allow the ast 151 * to be queued since the dlmthread is already 152 * frozen. but the recovery lock is always locked 153 * with LKM_NOQUEUE so we do not need the ast in 154 * this special case */ 155 if (!dlm_is_recovery_lock(res->lockname.name, 156 res->lockname.len)) { 157 kick_thread = 1; 158 call_ast = 1; 159 } else { 160 mlog(0, "%s: returning DLM_NORMAL to " 161 "node %u for reco lock\n", dlm->name, 162 lock->ml.node); 163 } 164 } else { 165 /* for NOQUEUE request, unless we get the 166 * lock right away, return DLM_NOTQUEUED */ 167 if (flags & LKM_NOQUEUE) { 168 status = DLM_NOTQUEUED; 169 if (dlm_is_recovery_lock(res->lockname.name, 170 res->lockname.len)) { 171 mlog(0, "%s: returning NOTQUEUED to " 172 "node %u for reco lock\n", dlm->name, 173 lock->ml.node); 174 } 175 } else { 176 status = DLM_NORMAL; 177 dlm_lock_get(lock); 178 list_add_tail(&lock->list, &res->blocked); 179 kick_thread = 1; 180 } 181 } 182 183 spin_unlock(&res->spinlock); 184 wake_up(&res->wq); 185 186 /* either queue the ast or release it */ 187 if (call_ast) 188 dlm_queue_ast(dlm, lock); 189 else 190 dlm_lockres_release_ast(dlm, res); 191 192 dlm_lockres_calc_usage(dlm, res); 193 if (kick_thread) 194 dlm_kick_thread(dlm, res); 195 196 return status; 197} 198 199void dlm_revert_pending_lock(struct dlm_lock_resource *res, 200 struct dlm_lock *lock) 201{ 202 /* remove from local queue if it failed */ 203 list_del_init(&lock->list); 204 lock->lksb->flags &= ~DLM_LKSB_GET_LVB; 205} 206 207 208/* 209 * locking: 210 * caller needs: none 211 * taken: takes and drops res->spinlock 212 * held on exit: none 213 * returns: DLM_DENIED, DLM_RECOVERING, or net status 214 */ 215static enum dlm_status dlmlock_remote(struct dlm_ctxt *dlm, 216 struct dlm_lock_resource *res, 217 struct dlm_lock *lock, int flags) 218{ 219 enum dlm_status status = DLM_DENIED; 220 int lockres_changed = 1; 221 222 mlog(0, "type=%d, lockres %.*s, flags = 0x%x\n", 223 lock->ml.type, res->lockname.len, 224 res->lockname.name, flags); 225 226 /* 227 * Wait if resource is getting recovered, remastered, etc. 228 * If the resource was remastered and new owner is self, then exit. 229 */ 230 spin_lock(&res->spinlock); 231 __dlm_wait_on_lockres(res); 232 if (res->owner == dlm->node_num) { 233 spin_unlock(&res->spinlock); 234 return DLM_RECOVERING; 235 } 236 res->state |= DLM_LOCK_RES_IN_PROGRESS; 237 238 /* add lock to local (secondary) queue */ 239 dlm_lock_get(lock); 240 list_add_tail(&lock->list, &res->blocked); 241 lock->lock_pending = 1; 242 spin_unlock(&res->spinlock); 243 244 /* spec seems to say that you will get DLM_NORMAL when the lock 245 * has been queued, meaning we need to wait for a reply here. */ 246 status = dlm_send_remote_lock_request(dlm, res, lock, flags); 247 248 spin_lock(&res->spinlock); 249 res->state &= ~DLM_LOCK_RES_IN_PROGRESS; 250 lock->lock_pending = 0; 251 if (status != DLM_NORMAL) { 252 if (status == DLM_RECOVERING && 253 dlm_is_recovery_lock(res->lockname.name, 254 res->lockname.len)) { 255 /* recovery lock was mastered by dead node. 256 * we need to have calc_usage shoot down this 257 * lockres and completely remaster it. */ 258 mlog(0, "%s: recovery lock was owned by " 259 "dead node %u, remaster it now.\n", 260 dlm->name, res->owner); 261 } else if (status != DLM_NOTQUEUED) { 262 /* 263 * DO NOT call calc_usage, as this would unhash 264 * the remote lockres before we ever get to use 265 * it. treat as if we never made any change to 266 * the lockres. 267 */ 268 lockres_changed = 0; 269 dlm_error(status); 270 } 271 dlm_revert_pending_lock(res, lock); 272 dlm_lock_put(lock); 273 } else if (dlm_is_recovery_lock(res->lockname.name, 274 res->lockname.len)) { 275 /* special case for the $RECOVERY lock. 276 * there will never be an AST delivered to put 277 * this lock on the proper secondary queue 278 * (granted), so do it manually. */ 279 mlog(0, "%s: $RECOVERY lock for this node (%u) is " 280 "mastered by %u; got lock, manually granting (no ast)\n", 281 dlm->name, dlm->node_num, res->owner); 282 list_move_tail(&lock->list, &res->granted); 283 } 284 spin_unlock(&res->spinlock); 285 286 if (lockres_changed) 287 dlm_lockres_calc_usage(dlm, res); 288 289 wake_up(&res->wq); 290 return status; 291} 292 293 294/* for remote lock creation. 295 * locking: 296 * caller needs: none, but need res->state & DLM_LOCK_RES_IN_PROGRESS 297 * taken: none 298 * held on exit: none 299 * returns: DLM_NOLOCKMGR, or net status 300 */ 301static enum dlm_status dlm_send_remote_lock_request(struct dlm_ctxt *dlm, 302 struct dlm_lock_resource *res, 303 struct dlm_lock *lock, int flags) 304{ 305 struct dlm_create_lock create; 306 int tmpret, status = 0; 307 enum dlm_status ret; 308 309 memset(&create, 0, sizeof(create)); 310 create.node_idx = dlm->node_num; 311 create.requested_type = lock->ml.type; 312 create.cookie = lock->ml.cookie; 313 create.namelen = res->lockname.len; 314 create.flags = cpu_to_be32(flags); 315 memcpy(create.name, res->lockname.name, create.namelen); 316 317 tmpret = o2net_send_message(DLM_CREATE_LOCK_MSG, dlm->key, &create, 318 sizeof(create), res->owner, &status); 319 if (tmpret >= 0) { 320 ret = status; 321 if (ret == DLM_REJECTED) { 322 mlog(ML_ERROR, "%s: res %.*s, Stale lockres no longer " 323 "owned by node %u. That node is coming back up " 324 "currently.\n", dlm->name, create.namelen, 325 create.name, res->owner); 326 dlm_print_one_lock_resource(res); 327 BUG(); 328 } 329 } else { 330 mlog(ML_ERROR, "%s: res %.*s, Error %d send CREATE LOCK to " 331 "node %u\n", dlm->name, create.namelen, create.name, 332 tmpret, res->owner); 333 if (dlm_is_host_down(tmpret)) 334 ret = DLM_RECOVERING; 335 else 336 ret = dlm_err_to_dlm_status(tmpret); 337 } 338 339 return ret; 340} 341 342void dlm_lock_get(struct dlm_lock *lock) 343{ 344 kref_get(&lock->lock_refs); 345} 346 347void dlm_lock_put(struct dlm_lock *lock) 348{ 349 kref_put(&lock->lock_refs, dlm_lock_release); 350} 351 352static void dlm_lock_release(struct kref *kref) 353{ 354 struct dlm_lock *lock; 355 356 lock = container_of(kref, struct dlm_lock, lock_refs); 357 358 BUG_ON(!list_empty(&lock->list)); 359 BUG_ON(!list_empty(&lock->ast_list)); 360 BUG_ON(!list_empty(&lock->bast_list)); 361 BUG_ON(lock->ast_pending); 362 BUG_ON(lock->bast_pending); 363 364 dlm_lock_detach_lockres(lock); 365 366 if (lock->lksb_kernel_allocated) { 367 mlog(0, "freeing kernel-allocated lksb\n"); 368 kfree(lock->lksb); 369 } 370 kmem_cache_free(dlm_lock_cache, lock); 371} 372 373/* associate a lock with it's lockres, getting a ref on the lockres */ 374void dlm_lock_attach_lockres(struct dlm_lock *lock, 375 struct dlm_lock_resource *res) 376{ 377 dlm_lockres_get(res); 378 lock->lockres = res; 379} 380 381/* drop ref on lockres, if there is still one associated with lock */ 382static void dlm_lock_detach_lockres(struct dlm_lock *lock) 383{ 384 struct dlm_lock_resource *res; 385 386 res = lock->lockres; 387 if (res) { 388 lock->lockres = NULL; 389 mlog(0, "removing lock's lockres reference\n"); 390 dlm_lockres_put(res); 391 } 392} 393 394static void dlm_init_lock(struct dlm_lock *newlock, int type, 395 u8 node, u64 cookie) 396{ 397 INIT_LIST_HEAD(&newlock->list); 398 INIT_LIST_HEAD(&newlock->ast_list); 399 INIT_LIST_HEAD(&newlock->bast_list); 400 spin_lock_init(&newlock->spinlock); 401 newlock->ml.type = type; 402 newlock->ml.convert_type = LKM_IVMODE; 403 newlock->ml.highest_blocked = LKM_IVMODE; 404 newlock->ml.node = node; 405 newlock->ml.pad1 = 0; 406 newlock->ml.list = 0; 407 newlock->ml.flags = 0; 408 newlock->ast = NULL; 409 newlock->bast = NULL; 410 newlock->astdata = NULL; 411 newlock->ml.cookie = cpu_to_be64(cookie); 412 newlock->ast_pending = 0; 413 newlock->bast_pending = 0; 414 newlock->convert_pending = 0; 415 newlock->lock_pending = 0; 416 newlock->unlock_pending = 0; 417 newlock->cancel_pending = 0; 418 newlock->lksb_kernel_allocated = 0; 419 420 kref_init(&newlock->lock_refs); 421} 422 423struct dlm_lock * dlm_new_lock(int type, u8 node, u64 cookie, 424 struct dlm_lockstatus *lksb) 425{ 426 struct dlm_lock *lock; 427 int kernel_allocated = 0; 428 429 lock = kmem_cache_zalloc(dlm_lock_cache, GFP_NOFS); 430 if (!lock) 431 return NULL; 432 433 if (!lksb) { 434 /* zero memory only if kernel-allocated */ 435 lksb = kzalloc(sizeof(*lksb), GFP_NOFS); 436 if (!lksb) { 437 kmem_cache_free(dlm_lock_cache, lock); 438 return NULL; 439 } 440 kernel_allocated = 1; 441 } 442 443 dlm_init_lock(lock, type, node, cookie); 444 if (kernel_allocated) 445 lock->lksb_kernel_allocated = 1; 446 lock->lksb = lksb; 447 lksb->lockid = lock; 448 return lock; 449} 450 451/* handler for lock creation net message 452 * locking: 453 * caller needs: none 454 * taken: takes and drops res->spinlock 455 * held on exit: none 456 * returns: DLM_NORMAL, DLM_SYSERR, DLM_IVLOCKID, DLM_NOTQUEUED 457 */ 458int dlm_create_lock_handler(struct o2net_msg *msg, u32 len, void *data, 459 void **ret_data) 460{ 461 struct dlm_ctxt *dlm = data; 462 struct dlm_create_lock *create = (struct dlm_create_lock *)msg->buf; 463 struct dlm_lock_resource *res = NULL; 464 struct dlm_lock *newlock = NULL; 465 struct dlm_lockstatus *lksb = NULL; 466 enum dlm_status status = DLM_NORMAL; 467 char *name; 468 unsigned int namelen; 469 470 BUG_ON(!dlm); 471 472 if (!dlm_grab(dlm)) 473 return DLM_REJECTED; 474 475 name = create->name; 476 namelen = create->namelen; 477 status = DLM_REJECTED; 478 if (!dlm_domain_fully_joined(dlm)) { 479 mlog(ML_ERROR, "Domain %s not fully joined, but node %u is " 480 "sending a create_lock message for lock %.*s!\n", 481 dlm->name, create->node_idx, namelen, name); 482 dlm_error(status); 483 goto leave; 484 } 485 486 status = DLM_IVBUFLEN; 487 if (namelen > DLM_LOCKID_NAME_MAX) { 488 dlm_error(status); 489 goto leave; 490 } 491 492 status = DLM_SYSERR; 493 newlock = dlm_new_lock(create->requested_type, 494 create->node_idx, 495 be64_to_cpu(create->cookie), NULL); 496 if (!newlock) { 497 dlm_error(status); 498 goto leave; 499 } 500 501 lksb = newlock->lksb; 502 503 if (be32_to_cpu(create->flags) & LKM_GET_LVB) { 504 lksb->flags |= DLM_LKSB_GET_LVB; 505 mlog(0, "set DLM_LKSB_GET_LVB flag\n"); 506 } 507 508 status = DLM_IVLOCKID; 509 res = dlm_lookup_lockres(dlm, name, namelen); 510 if (!res) { 511 dlm_error(status); 512 goto leave; 513 } 514 515 spin_lock(&res->spinlock); 516 status = __dlm_lockres_state_to_status(res); 517 spin_unlock(&res->spinlock); 518 519 if (status != DLM_NORMAL) { 520 mlog(0, "lockres recovering/migrating/in-progress\n"); 521 goto leave; 522 } 523 524 dlm_lock_attach_lockres(newlock, res); 525 526 status = dlmlock_master(dlm, res, newlock, be32_to_cpu(create->flags)); 527leave: 528 if (status != DLM_NORMAL) 529 if (newlock) 530 dlm_lock_put(newlock); 531 532 if (res) 533 dlm_lockres_put(res); 534 535 dlm_put(dlm); 536 537 return status; 538} 539 540 541/* fetch next node-local (u8 nodenum + u56 cookie) into u64 */ 542static inline void dlm_get_next_cookie(u8 node_num, u64 *cookie) 543{ 544 u64 tmpnode = node_num; 545 546 /* shift single byte of node num into top 8 bits */ 547 tmpnode <<= 56; 548 549 spin_lock(&dlm_cookie_lock); 550 *cookie = (dlm_next_cookie | tmpnode); 551 if (++dlm_next_cookie & 0xff00000000000000ull) { 552 mlog(0, "This node's cookie will now wrap!\n"); 553 dlm_next_cookie = 1; 554 } 555 spin_unlock(&dlm_cookie_lock); 556} 557 558enum dlm_status dlmlock(struct dlm_ctxt *dlm, int mode, 559 struct dlm_lockstatus *lksb, int flags, 560 const char *name, int namelen, dlm_astlockfunc_t *ast, 561 void *data, dlm_bastlockfunc_t *bast) 562{ 563 enum dlm_status status; 564 struct dlm_lock_resource *res = NULL; 565 struct dlm_lock *lock = NULL; 566 int convert = 0, recovery = 0; 567 568 /* yes this function is a mess. 569 * TODO: clean this up. lots of common code in the 570 * lock and convert paths, especially in the retry blocks */ 571 if (!lksb) { 572 dlm_error(DLM_BADARGS); 573 return DLM_BADARGS; 574 } 575 576 status = DLM_BADPARAM; 577 if (mode != LKM_EXMODE && mode != LKM_PRMODE && mode != LKM_NLMODE) { 578 dlm_error(status); 579 goto error; 580 } 581 582 if (flags & ~LKM_VALID_FLAGS) { 583 dlm_error(status); 584 goto error; 585 } 586 587 convert = (flags & LKM_CONVERT); 588 recovery = (flags & LKM_RECOVERY); 589 590 if (recovery && 591 (!dlm_is_recovery_lock(name, namelen) || convert) ) { 592 dlm_error(status); 593 goto error; 594 } 595 if (convert && (flags & LKM_LOCAL)) { 596 mlog(ML_ERROR, "strange LOCAL convert request!\n"); 597 goto error; 598 } 599 600 if (convert) { 601 /* CONVERT request */ 602 603 /* if converting, must pass in a valid dlm_lock */ 604 lock = lksb->lockid; 605 if (!lock) { 606 mlog(ML_ERROR, "NULL lock pointer in convert " 607 "request\n"); 608 goto error; 609 } 610 611 res = lock->lockres; 612 if (!res) { 613 mlog(ML_ERROR, "NULL lockres pointer in convert " 614 "request\n"); 615 goto error; 616 } 617 dlm_lockres_get(res); 618 619 /* XXX: for ocfs2 purposes, the ast/bast/astdata/lksb are 620 * static after the original lock call. convert requests will 621 * ensure that everything is the same, or return DLM_BADARGS. 622 * this means that DLM_DENIED_NOASTS will never be returned. 623 */ 624 if (lock->lksb != lksb || lock->ast != ast || 625 lock->bast != bast || lock->astdata != data) { 626 status = DLM_BADARGS; 627 mlog(ML_ERROR, "new args: lksb=%p, ast=%p, bast=%p, " 628 "astdata=%p\n", lksb, ast, bast, data); 629 mlog(ML_ERROR, "orig args: lksb=%p, ast=%p, bast=%p, " 630 "astdata=%p\n", lock->lksb, lock->ast, 631 lock->bast, lock->astdata); 632 goto error; 633 } 634retry_convert: 635 dlm_wait_for_recovery(dlm); 636 637 if (res->owner == dlm->node_num) 638 status = dlmconvert_master(dlm, res, lock, flags, mode); 639 else 640 status = dlmconvert_remote(dlm, res, lock, flags, mode); 641 if (status == DLM_RECOVERING || status == DLM_MIGRATING || 642 status == DLM_FORWARD) { 643 /* for now, see how this works without sleeping 644 * and just retry right away. I suspect the reco 645 * or migration will complete fast enough that 646 * no waiting will be necessary */ 647 mlog(0, "retrying convert with migration/recovery/" 648 "in-progress\n"); 649 msleep(100); 650 goto retry_convert; 651 } 652 } else { 653 u64 tmpcookie; 654 655 /* LOCK request */ 656 status = DLM_BADARGS; 657 if (!name) { 658 dlm_error(status); 659 goto error; 660 } 661 662 status = DLM_IVBUFLEN; 663 if (namelen > DLM_LOCKID_NAME_MAX || namelen < 1) { 664 dlm_error(status); 665 goto error; 666 } 667 668 dlm_get_next_cookie(dlm->node_num, &tmpcookie); 669 lock = dlm_new_lock(mode, dlm->node_num, tmpcookie, lksb); 670 if (!lock) { 671 dlm_error(status); 672 goto error; 673 } 674 675 if (!recovery) 676 dlm_wait_for_recovery(dlm); 677 678 /* find or create the lock resource */ 679 res = dlm_get_lock_resource(dlm, name, namelen, flags); 680 if (!res) { 681 status = DLM_IVLOCKID; 682 dlm_error(status); 683 goto error; 684 } 685 686 mlog(0, "type=%d, flags = 0x%x\n", mode, flags); 687 mlog(0, "creating lock: lock=%p res=%p\n", lock, res); 688 689 dlm_lock_attach_lockres(lock, res); 690 lock->ast = ast; 691 lock->bast = bast; 692 lock->astdata = data; 693 694retry_lock: 695 if (flags & LKM_VALBLK) { 696 mlog(0, "LKM_VALBLK passed by caller\n"); 697 698 /* LVB requests for non PR, PW or EX locks are 699 * ignored. */ 700 if (mode < LKM_PRMODE) 701 flags &= ~LKM_VALBLK; 702 else { 703 flags |= LKM_GET_LVB; 704 lock->lksb->flags |= DLM_LKSB_GET_LVB; 705 } 706 } 707 708 if (res->owner == dlm->node_num) 709 status = dlmlock_master(dlm, res, lock, flags); 710 else 711 status = dlmlock_remote(dlm, res, lock, flags); 712 713 if (status == DLM_RECOVERING || status == DLM_MIGRATING || 714 status == DLM_FORWARD) { 715 msleep(100); 716 if (recovery) { 717 if (status != DLM_RECOVERING) 718 goto retry_lock; 719 /* wait to see the node go down, then 720 * drop down and allow the lockres to 721 * get cleaned up. need to remaster. */ 722 dlm_wait_for_node_death(dlm, res->owner, 723 DLM_NODE_DEATH_WAIT_MAX); 724 } else { 725 dlm_wait_for_recovery(dlm); 726 goto retry_lock; 727 } 728 } 729 730 /* Inflight taken in dlm_get_lock_resource() is dropped here */ 731 spin_lock(&res->spinlock); 732 dlm_lockres_drop_inflight_ref(dlm, res); 733 spin_unlock(&res->spinlock); 734 735 dlm_lockres_calc_usage(dlm, res); 736 dlm_kick_thread(dlm, res); 737 738 if (status != DLM_NORMAL) { 739 lock->lksb->flags &= ~DLM_LKSB_GET_LVB; 740 if (status != DLM_NOTQUEUED) 741 dlm_error(status); 742 goto error; 743 } 744 } 745 746error: 747 if (status != DLM_NORMAL) { 748 if (lock && !convert) 749 dlm_lock_put(lock); 750 // this is kind of unnecessary 751 lksb->status = status; 752 } 753 754 /* put lockres ref from the convert path 755 * or from dlm_get_lock_resource */ 756 if (res) 757 dlm_lockres_put(res); 758 759 return status; 760} 761EXPORT_SYMBOL_GPL(dlmlock); 762