lustre/lfsck/lfsck_engine.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,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License version 2 for more details.  A copy is
  14  * included in the COPYING file that accompanied this code.
  15
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  19  *
  20  * GPL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 2013, 2015, Intel Corporation.
  24  */
  25 /*
  26  * lustre/lfsck/lfsck_engine.c
  27  *
  28  * Author: Fan, Yong <fan.yong@intel.com>
  29  */
  30
  31 #define DEBUG_SUBSYSTEM S_LFSCK
  32
  33 #include <lu_object.h>
  34 #include <dt_object.h>
  35 #include <lustre_net.h>
  36 #include <lustre_fid.h>
  37 #include <obd_support.h>
  38 #include <lustre_lib.h>
  39
  40 #include "lfsck_internal.h"
  41
  42 int lfsck_unpack_ent(struct lu_dirent *ent, __u64 *cookie, __u16 *type)
  43 {
  44         struct luda_type        *lt;
  45         int                      align = sizeof(*lt) - 1;
  46         int                      len;
  47
  48         fid_le_to_cpu(&ent->lde_fid, &ent->lde_fid);
  49         *cookie = le64_to_cpu(ent->lde_hash);
  50         ent->lde_reclen = le16_to_cpu(ent->lde_reclen);
  51         ent->lde_namelen = le16_to_cpu(ent->lde_namelen);
  52         ent->lde_attrs = le32_to_cpu(ent->lde_attrs);
  53
  54         if (unlikely(!(ent->lde_attrs & LUDA_TYPE)))
  55                 return -EINVAL;
  56
  57         len = (ent->lde_namelen + align) & ~align;
  58         lt = (struct luda_type *)(ent->lde_name + len);
  59         *type = le16_to_cpu(lt->lt_type);
  60
  61         /* Make sure the name is terminated with '\0'. The data (object type)
  62          * after ent::lde_name maybe broken, but we have stored such data in
  63          * the output parameter @type as above. */
  64         ent->lde_name[ent->lde_namelen] = '\0';
  65
  66         return 0;
  67 }
  68
  69 static void lfsck_di_oit_put(const struct lu_env *env, struct lfsck_instance *lfsck)
  70 {
  71         const struct dt_it_ops  *iops;
  72         struct dt_it            *di;
  73
  74         spin_lock(&lfsck->li_lock);
  75         iops = &lfsck->li_obj_oit->do_index_ops->dio_it;
  76         di = lfsck->li_di_oit;
  77         lfsck->li_di_oit = NULL;
  78         spin_unlock(&lfsck->li_lock);
  79         iops->put(env, di);
  80 }
  81
  82 static void lfsck_di_dir_put(const struct lu_env *env, struct lfsck_instance *lfsck)
  83 {
  84         const struct dt_it_ops  *iops;
  85         struct dt_it            *di;
  86
  87         spin_lock(&lfsck->li_lock);
  88         iops = &lfsck->li_obj_dir->do_index_ops->dio_it;
  89         di = lfsck->li_di_dir;
  90         lfsck->li_di_dir = NULL;
  91         lfsck->li_cookie_dir = 0;
  92         spin_unlock(&lfsck->li_lock);
  93         iops->put(env, di);
  94 }
  95
  96 static int lfsck_parent_fid(const struct lu_env *env, struct dt_object *obj,
  97                             struct lu_fid *fid)
  98 {
  99         if (unlikely(!S_ISDIR(lfsck_object_type(obj)) ||
 100                      !dt_try_as_dir(env, obj)))
 101                 return -ENOTDIR;
 102
 103         return dt_lookup(env, obj, (struct dt_rec *)fid,
 104                          (const struct dt_key *)"..");
 105 }
 106
 107 /**
 108  * Check whether needs to scan the directory or not.
 109  *
 110  * 1) If we are not doing namespace LFSCK, or the given @obj is not directory,
 111  *    then needs not to scan the @obj. Otherwise,
 112  * 2) Global /ROOT needs to be scanned, backend root needs not to be scanned.
 113  * 3) If the @obj is neither IGIF nor normal FID (including .lustre and its
 114  *    sub-directories that have been scanned when the LFSCK engine start),
 115  *    then needs not to be scanned.
 116  * 4) If it is a remote object, then scanning the object will be done on the
 117  *    MDT on which the object really resides.
 118  * 5) If the local object has normal FID, then needs to be scanned. Otherwise,
 119  * 6) If the object has linkEA, then needs to be scanned. Otherwise,
 120  * 7) If none of the previous conditions are true, we need to check the parent
 121  *    directories whether this subdirectory is in a tree that should be scanned.
 122  *    Set the parent as current @obj, repeat 2)-7).
 123  *
 124  * \param[in] env       pointer to the thread context
 125  * \param[in] lfsck     pointer to the lfsck instance
 126  * \param[in] obj       pointer to the object to be checked
 127  *
 128  * \retval              positive number if the directory needs to be scanned
 129  * \retval              0 if the directory needs NOT to be scanned
 130  * \retval              negative error number on failure
 131  */
 132 static int lfsck_needs_scan_dir(const struct lu_env *env,
 133                                 struct lfsck_instance *lfsck,
 134                                 struct dt_object *obj)
 135 {
 136         struct lfsck_thread_info *info    = lfsck_env_info(env);
 137         struct lu_fid            *fid     = &info->lti_fid;
 138         struct lu_seq_range      *range   = &info->lti_range;
 139         struct seq_server_site   *ss      = lfsck_dev_site(lfsck);
 140         __u32                     idx     = lfsck_dev_idx(lfsck);
 141         int                       depth   = 0;
 142         int                       rc      = 0;
 143
 144         if (list_empty(&lfsck->li_list_dir) || !S_ISDIR(lfsck_object_type(obj)))
 145                 return 0;
 146
 147         LASSERT(ss != NULL);
 148
 149         *fid = *lfsck_dto2fid(obj);
 150         while (1) {
 151                 /* Global /ROOT is visible. */
 152                 if (unlikely(lu_fid_eq(fid, &lfsck->li_global_root_fid)))
 153                         return 1;
 154
 155                 /* Backend root is invisible. */
 156                 if (unlikely(lu_fid_eq(fid, &lfsck->li_local_root_fid)))
 157                         return 0;
 158
 159                 if (!fid_is_norm(fid) && !fid_is_igif(fid))
 160                         return 0;
 161
 162                 fld_range_set_mdt(range);
 163                 rc = fld_local_lookup(env, ss->ss_server_fld,
 164                                       fid_seq(fid), range);
 165                 if (rc != 0 || range->lsr_index != idx)
 166                         /* Current FID should NOT be for the input parameter
 167                          * @obj, because the lfsck_master_oit_engine() has
 168                          * filtered out agent object. So current FID is for
 169                          * the ancestor of the original input parameter @obj.
 170                          * So the ancestor is a remote directory. The input
 171                          * parameter @obj is local directory, and should be
 172                          * scanned under such case. */
 173                         return 1;
 174
 175                 /* normal FID on this target (locally) must be for the
 176                  * client-side visiable object. */
 177                 if (fid_is_norm(fid))
 178                         return 1;
 179
 180                 if (obj == NULL) {
 181                         obj = lfsck_object_find_bottom(env, lfsck, fid);
 182                         if (IS_ERR(obj))
 183                                 return PTR_ERR(obj);
 184
 185                         depth++;
 186                         if (!dt_object_exists(obj))
 187                                 GOTO(out, rc = 0);
 188                 }
 189
 190                 dt_read_lock(env, obj, MOR_TGT_CHILD);
 191                 if (unlikely(lfsck_is_dead_obj(obj))) {
 192                         dt_read_unlock(env, obj);
 193
 194                         GOTO(out, rc = 0);
 195                 }
 196
 197                 rc = dt_xattr_get(env, obj,
 198                                   lfsck_buf_get(env, NULL, 0), XATTR_NAME_LINK);
 199                 dt_read_unlock(env, obj);
 200                 if (rc >= 0)
 201                         GOTO(out, rc = 1);
 202
 203                 if (rc < 0 && rc != -ENODATA)
 204                         GOTO(out, rc);
 205
 206                 rc = lfsck_parent_fid(env, obj, fid);
 207                 if (depth > 0)
 208                         lfsck_object_put(env, obj);
 209
 210                 obj = NULL;
 211                 if (rc != 0)
 212                         return rc;
 213
 214                 if (!fid_is_sane(fid))
 215                         return 0;
 216         }
 217
 218 out:
 219         if (depth > 0 && obj != NULL)
 220                 lfsck_object_put(env, obj);
 221
 222         return rc;
 223 }
 224
 225 static int lfsck_load_stripe_lmv(const struct lu_env *env,
 226                                  struct lfsck_instance *lfsck,
 227                                  struct dt_object *obj)
 228 {
 229         struct lmv_mds_md_v1    *lmv    = &lfsck_env_info(env)->lti_lmv;
 230         struct lfsck_lmv        *llmv;
 231         int                      rc;
 232         ENTRY;
 233
 234         LASSERT(lfsck->li_obj_dir == NULL);
 235         LASSERT(lfsck->li_lmv == NULL);
 236
 237         rc = lfsck_read_stripe_lmv(env, obj, lmv);
 238         if (rc == -ENODATA) {
 239                 lfsck->li_obj_dir = lfsck_object_get(obj);
 240
 241                 RETURN(0);
 242         }
 243
 244         if (rc < 0)
 245                 RETURN(rc);
 246
 247         OBD_ALLOC_PTR(llmv);
 248         if (llmv == NULL)
 249                 RETURN(-ENOMEM);
 250
 251         if (lmv->lmv_magic == LMV_MAGIC) {
 252                 struct lfsck_slave_lmv_rec      *lslr;
 253                 __u32                            stripes;
 254
 255                 llmv->ll_lmv_master = 1;
 256                 if (lmv->lmv_stripe_count < 1)
 257                         stripes = LFSCK_LMV_DEF_STRIPES;
 258                 else if (lmv->lmv_stripe_count > LFSCK_LMV_MAX_STRIPES)
 259                         stripes = LFSCK_LMV_MAX_STRIPES;
 260                 else
 261                         stripes = lmv->lmv_stripe_count;
 262
 263                 OBD_ALLOC_LARGE(lslr, sizeof(*lslr) * stripes);
 264                 if (lslr == NULL) {
 265                         OBD_FREE_PTR(llmv);
 266
 267                         RETURN(-ENOMEM);
 268                 }
 269
 270                 llmv->ll_stripes_allocated = stripes;
 271                 llmv->ll_hash_type = LMV_HASH_TYPE_UNKNOWN;
 272                 llmv->ll_lslr = lslr;
 273         } else {
 274                 llmv->ll_lmv_slave = 1;
 275         }
 276
 277         lfsck->li_obj_dir = lfsck_object_get(obj);
 278         llmv->ll_lmv = *lmv;
 279         atomic_set(&llmv->ll_ref, 1);
 280         lfsck->li_lmv = llmv;
 281
 282         RETURN(0);
 283 }
 284
 285 /* LFSCK wrap functions */
 286
 287 static void lfsck_fail(const struct lu_env *env, struct lfsck_instance *lfsck,
 288                        bool new_checked)
 289 {
 290         struct lfsck_component *com;
 291
 292         list_for_each_entry(com, &lfsck->li_list_scan, lc_link) {
 293                 com->lc_ops->lfsck_fail(env, com, new_checked);
 294         }
 295 }
 296
 297 void lfsck_close_dir(const struct lu_env *env,
 298                      struct lfsck_instance *lfsck, int result)
 299 {
 300         struct lfsck_component *com;
 301         ENTRY;
 302
 303         if (lfsck->li_lmv != NULL) {
 304                 lfsck->li_lmv->ll_exit_value = result;
 305                 if (lfsck->li_obj_dir != NULL) {
 306                         list_for_each_entry(com, &lfsck->li_list_dir,
 307                                             lc_link_dir) {
 308                                 com->lc_ops->lfsck_close_dir(env, com);
 309                         }
 310                 }
 311
 312                 lfsck_lmv_put(env, lfsck->li_lmv);
 313                 lfsck->li_lmv = NULL;
 314         }
 315
 316         if (lfsck->li_di_dir != NULL) {
 317                 const struct dt_it_ops  *dir_iops;
 318                 struct dt_it            *dir_di   = lfsck->li_di_dir;
 319
 320                 LASSERT(lfsck->li_obj_dir != NULL);
 321
 322                 dir_iops = &lfsck->li_obj_dir->do_index_ops->dio_it;
 323                 lfsck_di_dir_put(env, lfsck);
 324                 dir_iops->fini(env, dir_di);
 325         }
 326
 327         if (lfsck->li_obj_dir != NULL) {
 328                 struct dt_object        *dir_obj  = lfsck->li_obj_dir;
 329
 330                 lfsck->li_obj_dir = NULL;
 331                 lfsck_object_put(env, dir_obj);
 332         }
 333
 334         EXIT;
 335 }
 336
 337 int lfsck_open_dir(const struct lu_env *env,
 338                    struct lfsck_instance *lfsck, __u64 cookie)
 339 {
 340         struct dt_object        *obj    = lfsck->li_obj_dir;
 341         struct dt_it            *di     = lfsck->li_di_dir;
 342         struct lfsck_component  *com;
 343         const struct dt_it_ops  *iops;
 344         int                      rc     = 0;
 345         ENTRY;
 346
 347         LASSERT(obj != NULL);
 348         LASSERT(di == NULL);
 349
 350         if (unlikely(!dt_try_as_dir(env, obj)))
 351                 GOTO(out, rc = -ENOTDIR);
 352
 353         list_for_each_entry(com, &lfsck->li_list_dir, lc_link_dir) {
 354                 rc = com->lc_ops->lfsck_open_dir(env, com);
 355                 if (rc != 0)
 356                         GOTO(out, rc);
 357         }
 358
 359         iops = &obj->do_index_ops->dio_it;
 360         di = iops->init(env, obj, lfsck->li_args_dir);
 361         if (IS_ERR(di))
 362                 GOTO(out, rc = PTR_ERR(di));
 363
 364         rc = iops->load(env, di, cookie);
 365         if (rc == 0 || (rc > 0 && cookie > 0))
 366                 rc = iops->next(env, di);
 367         else if (rc > 0)
 368                 rc = 0;
 369
 370         if (rc != 0) {
 371                 iops->put(env, di);
 372                 iops->fini(env, di);
 373         } else {
 374                 lfsck->li_cookie_dir = iops->store(env, di);
 375                 spin_lock(&lfsck->li_lock);
 376                 lfsck->li_di_dir = di;
 377                 spin_unlock(&lfsck->li_lock);
 378         }
 379
 380         GOTO(out, rc);
 381
 382 out:
 383         if (rc != 0)
 384                 lfsck_close_dir(env, lfsck, rc);
 385
 386         return rc;
 387 }
 388
 389 static int lfsck_checkpoint(const struct lu_env *env,
 390                             struct lfsck_instance *lfsck)
 391 {
 392         struct lfsck_component *com;
 393         int                     rc  = 0;
 394         int                     rc1 = 0;
 395
 396         if (likely(cfs_time_beforeq(cfs_time_current(),
 397                                     lfsck->li_time_next_checkpoint)))
 398                 return 0;
 399
 400         lfsck_pos_fill(env, lfsck, &lfsck->li_pos_checkpoint, false);
 401         list_for_each_entry(com, &lfsck->li_list_scan, lc_link) {
 402                 rc = com->lc_ops->lfsck_checkpoint(env, com, false);
 403                 if (rc != 0)
 404                         rc1 = rc;
 405         }
 406
 407         lfsck->li_time_last_checkpoint = cfs_time_current();
 408         lfsck->li_time_next_checkpoint = lfsck->li_time_last_checkpoint +
 409                                 cfs_time_seconds(LFSCK_CHECKPOINT_INTERVAL);
 410         return rc1 != 0 ? rc1 : rc;
 411 }
 412
 413 static int lfsck_prep(const struct lu_env *env, struct lfsck_instance *lfsck,
 414                       struct lfsck_start_param *lsp)
 415 {
 416         struct dt_object       *obj     = NULL;
 417         struct lfsck_component *com;
 418         struct lfsck_component *next;
 419         struct lfsck_position  *pos     = NULL;
 420         const struct dt_it_ops *iops    =
 421                                 &lfsck->li_obj_oit->do_index_ops->dio_it;
 422         int                     rc;
 423         ENTRY;
 424
 425         LASSERT(lfsck->li_obj_dir == NULL);
 426         LASSERT(lfsck->li_di_dir == NULL);
 427
 428         lfsck->li_current_oit_processed = 0;
 429         list_for_each_entry_safe(com, next, &lfsck->li_list_scan, lc_link) {
 430                 com->lc_new_checked = 0;
 431                 rc = com->lc_ops->lfsck_prep(env, com, lsp);
 432                 if (rc != 0)
 433                         GOTO(out, rc);
 434
 435                 if ((pos == NULL) ||
 436                     (!lfsck_pos_is_zero(&com->lc_pos_start) &&
 437                      lfsck_pos_is_eq(pos, &com->lc_pos_start) > 0))
 438                         pos = &com->lc_pos_start;
 439         }
 440
 441         /* Init otable-based iterator. */
 442         if (pos == NULL) {
 443                 rc = iops->load(env, lfsck->li_di_oit, 0);
 444                 if (rc > 0) {
 445                         lfsck->li_oit_over = 1;
 446                         rc = 0;
 447                 }
 448
 449                 GOTO(out, rc);
 450         }
 451
 452         rc = iops->load(env, lfsck->li_di_oit, pos->lp_oit_cookie);
 453         if (rc < 0)
 454                 GOTO(out, rc);
 455         else if (rc > 0)
 456                 lfsck->li_oit_over = 1;
 457
 458         if (!lfsck->li_master || fid_is_zero(&pos->lp_dir_parent))
 459                 GOTO(out, rc = 0);
 460
 461         /* Find the directory for namespace-based traverse. */
 462         obj = lfsck_object_find_bottom(env, lfsck, &pos->lp_dir_parent);
 463         if (IS_ERR(obj))
 464                 RETURN(PTR_ERR(obj));
 465
 466         /* Remote directory will be scanned by the LFSCK instance
 467          * on the MDT where the remote object really resides on. */
 468         if (!dt_object_exists(obj) || dt_object_remote(obj) ||
 469             unlikely(!S_ISDIR(lfsck_object_type(obj))))
 470                 GOTO(out, rc = 0);
 471
 472         rc = lfsck_load_stripe_lmv(env, lfsck, obj);
 473         if (rc == 0) {
 474                 /* For the master MDT-object of a striped directory,
 475                  * reset the iteration from the directory beginning. */
 476                 if (lfsck->li_lmv != NULL && lfsck->li_lmv->ll_lmv_master)
 477                         pos->lp_dir_cookie = 0;
 478
 479                 rc = lfsck_open_dir(env, lfsck, pos->lp_dir_cookie);
 480                 if (rc > 0)
 481                         /* The end of the directory. */
 482                         rc = 0;
 483         }
 484
 485         GOTO(out, rc);
 486
 487 out:
 488         if (obj != NULL)
 489                 lfsck_object_put(env, obj);
 490
 491         if (rc != 0) {
 492                 lfsck_close_dir(env, lfsck, rc);
 493                 list_for_each_entry_safe(com, next, &lfsck->li_list_scan,
 494                                          lc_link) {
 495                         com->lc_ops->lfsck_post(env, com, rc, true);
 496                 }
 497
 498                 return rc;
 499         }
 500
 501         rc = 0;
 502         lfsck_pos_fill(env, lfsck, &lfsck->li_pos_checkpoint, true);
 503         lfsck->li_pos_current = lfsck->li_pos_checkpoint;
 504         list_for_each_entry(com, &lfsck->li_list_scan, lc_link) {
 505                 rc = com->lc_ops->lfsck_checkpoint(env, com, true);
 506                 if (rc != 0)
 507                         break;
 508         }
 509
 510         lfsck->li_time_last_checkpoint = cfs_time_current();
 511         lfsck->li_time_next_checkpoint = lfsck->li_time_last_checkpoint +
 512                                 cfs_time_seconds(LFSCK_CHECKPOINT_INTERVAL);
 513         return rc;
 514 }
 515
 516 static int lfsck_exec_oit(const struct lu_env *env,
 517                           struct lfsck_instance *lfsck, struct dt_object *obj)
 518 {
 519         struct lfsck_component *com;
 520         int                     rc;
 521         ENTRY;
 522
 523         LASSERT(lfsck->li_obj_dir == NULL);
 524
 525         list_for_each_entry(com, &lfsck->li_list_scan, lc_link) {
 526                 rc = com->lc_ops->lfsck_exec_oit(env, com, obj);
 527                 if (rc != 0)
 528                         RETURN(rc);
 529         }
 530
 531         rc = lfsck_needs_scan_dir(env, lfsck, obj);
 532         if (rc <= 0)
 533                 GOTO(out, rc);
 534
 535         rc = lfsck_load_stripe_lmv(env, lfsck, obj);
 536         if (rc == 0)
 537                 rc = lfsck_open_dir(env, lfsck, 0);
 538
 539         GOTO(out, rc);
 540
 541 out:
 542         if (rc < 0)
 543                 lfsck_fail(env, lfsck, false);
 544
 545         if (rc != 0)
 546                 lfsck_close_dir(env, lfsck, rc);
 547
 548         return rc > 0 ? 0 : rc;
 549 }
 550
 551 static int lfsck_exec_dir(const struct lu_env *env,
 552                           struct lfsck_instance *lfsck,
 553                           struct lfsck_assistant_object *lso,
 554                           struct lu_dirent *ent, __u16 type)
 555 {
 556         struct lfsck_component *com;
 557         int                     rc;
 558
 559         list_for_each_entry(com, &lfsck->li_list_scan, lc_link) {
 560                 rc = com->lc_ops->lfsck_exec_dir(env, com, lso, ent, type);
 561                 if (rc != 0)
 562                         return rc;
 563         }
 564         return 0;
 565 }
 566
 567 static int lfsck_master_dir_engine(const struct lu_env *env,
 568                                    struct lfsck_instance *lfsck);
 569
 570 static int lfsck_post(const struct lu_env *env, struct lfsck_instance *lfsck,
 571                       int result)
 572 {
 573         struct lfsck_component *com;
 574         struct lfsck_component *next;
 575         int                     rc  = result;
 576
 577         lfsck_pos_fill(env, lfsck, &lfsck->li_pos_checkpoint, false);
 578         lfsck_close_dir(env, lfsck, result);
 579
 580         while (thread_is_running(&lfsck->li_thread) && rc > 0 &&
 581                !list_empty(&lfsck->li_list_lmv)) {
 582                 struct lfsck_lmv_unit *llu;
 583
 584                 spin_lock(&lfsck->li_lock);
 585                 llu = list_entry(lfsck->li_list_lmv.next,
 586                                  struct lfsck_lmv_unit, llu_link);
 587                 list_del_init(&llu->llu_link);
 588                 spin_unlock(&lfsck->li_lock);
 589
 590                 lfsck->li_lmv = &llu->llu_lmv;
 591                 lfsck->li_obj_dir = lfsck_object_get(llu->llu_obj);
 592                 rc = lfsck_open_dir(env, lfsck, 0);
 593                 if (rc == 0) {
 594                         rc = lfsck_master_dir_engine(env, lfsck);
 595                         lfsck_close_dir(env, lfsck, result);
 596                 }
 597         }
 598
 599         result = rc;
 600
 601         list_for_each_entry_safe(com, next, &lfsck->li_list_scan, lc_link) {
 602                 rc = com->lc_ops->lfsck_post(env, com, result, false);
 603                 if (rc != 0)
 604                         CDEBUG(D_LFSCK, "%s: lfsck_post at the component %u: "
 605                                "rc = %d\n", lfsck_lfsck2name(lfsck),
 606                                (__u32)com->lc_type, rc);
 607         }
 608
 609         lfsck->li_time_last_checkpoint = cfs_time_current();
 610         lfsck->li_time_next_checkpoint = lfsck->li_time_last_checkpoint +
 611                                 cfs_time_seconds(LFSCK_CHECKPOINT_INTERVAL);
 612
 613         /* Ignore some component post failure to make other can go ahead. */
 614         return result;
 615 }
 616
 617 static int lfsck_double_scan(const struct lu_env *env,
 618                              struct lfsck_instance *lfsck)
 619 {
 620         struct lfsck_component *com;
 621         struct lfsck_component *next;
 622         struct l_wait_info      lwi = { 0 };
 623         int                     rc  = 0;
 624         int                     rc1 = 0;
 625
 626         list_for_each_entry(com, &lfsck->li_list_double_scan, lc_link) {
 627                 rc = com->lc_ops->lfsck_double_scan(env, com);
 628                 if (rc != 0)
 629                         rc1 = rc;
 630         }
 631
 632         l_wait_event(lfsck->li_thread.t_ctl_waitq,
 633                      atomic_read(&lfsck->li_double_scan_count) == 0,
 634                      &lwi);
 635
 636         if (lfsck->li_status != LS_PAUSED &&
 637             lfsck->li_status != LS_CO_PAUSED) {
 638                 list_for_each_entry_safe(com, next, &lfsck->li_list_double_scan,
 639                                          lc_link) {
 640                         spin_lock(&lfsck->li_lock);
 641                         list_move_tail(&com->lc_link, &lfsck->li_list_idle);
 642                         spin_unlock(&lfsck->li_lock);
 643                 }
 644         }
 645
 646         return rc1 != 0 ? rc1 : rc;
 647 }
 648
 649 static void lfsck_quit(const struct lu_env *env, struct lfsck_instance *lfsck)
 650 {
 651         struct lfsck_component *com;
 652         struct lfsck_component *next;
 653
 654         list_for_each_entry_safe(com, next, &lfsck->li_list_scan,
 655                                  lc_link) {
 656                 if (com->lc_ops->lfsck_quit != NULL)
 657                         com->lc_ops->lfsck_quit(env, com);
 658
 659                 spin_lock(&lfsck->li_lock);
 660                 list_del_init(&com->lc_link_dir);
 661                 list_move_tail(&com->lc_link, &lfsck->li_list_idle);
 662                 spin_unlock(&lfsck->li_lock);
 663         }
 664
 665         list_for_each_entry_safe(com, next, &lfsck->li_list_double_scan,
 666                                  lc_link) {
 667                 if (com->lc_ops->lfsck_quit != NULL)
 668                         com->lc_ops->lfsck_quit(env, com);
 669
 670                 spin_lock(&lfsck->li_lock);
 671                 list_move_tail(&com->lc_link, &lfsck->li_list_idle);
 672                 spin_unlock(&lfsck->li_lock);
 673         }
 674 }
 675
 676 /* LFSCK engines */
 677
 678 static int lfsck_master_dir_engine(const struct lu_env *env,
 679                                    struct lfsck_instance *lfsck)
 680 {
 681         struct lfsck_thread_info        *info   = lfsck_env_info(env);
 682         struct dt_object                *dir    = lfsck->li_obj_dir;
 683         const struct dt_it_ops          *iops   = &dir->do_index_ops->dio_it;
 684         struct dt_it                    *di     = lfsck->li_di_dir;
 685         struct lu_dirent                *ent    =
 686                         (struct lu_dirent *)info->lti_key;
 687         struct lfsck_bookmark           *bk     = &lfsck->li_bookmark_ram;
 688         struct ptlrpc_thread            *thread = &lfsck->li_thread;
 689         struct lfsck_assistant_object   *lso    = NULL;
 690         int                              rc;
 691         __u16                            type;
 692         ENTRY;
 693
 694         do {
 695                 if (CFS_FAIL_TIMEOUT(OBD_FAIL_LFSCK_DELAY2, cfs_fail_val) &&
 696                     unlikely(!thread_is_running(thread))) {
 697                         CDEBUG(D_LFSCK, "%s: scan dir exit for engine stop, "
 698                                "parent "DFID", cookie "LPX64"\n",
 699                                lfsck_lfsck2name(lfsck),
 700                                PFID(lfsck_dto2fid(dir)), lfsck->li_cookie_dir);
 701
 702                         GOTO(out, rc = 0);
 703                 }
 704
 705                 lfsck->li_new_scanned++;
 706                 rc = iops->rec(env, di, (struct dt_rec *)ent,
 707                                lfsck->li_args_dir);
 708                 if (rc == 0)
 709                         rc = lfsck_unpack_ent(ent, &lfsck->li_cookie_dir,
 710                                               &type);
 711
 712                 if (rc != 0) {
 713                         CDEBUG(D_LFSCK, "%s: scan dir failed at rec(), "
 714                                "parent "DFID", cookie "LPX64": rc = %d\n",
 715                                lfsck_lfsck2name(lfsck),
 716                                PFID(lfsck_dto2fid(dir)),
 717                                lfsck->li_cookie_dir, rc);
 718                         lfsck_fail(env, lfsck, true);
 719                         if (bk->lb_param & LPF_FAILOUT)
 720                                 GOTO(out, rc);
 721                         else
 722                                 goto checkpoint;
 723                 }
 724
 725                 if (ent->lde_attrs & LUDA_IGNORE)
 726                         goto checkpoint;
 727
 728                 /* skip dot entry. */
 729                 if (ent->lde_namelen == 1 && ent->lde_name[0] == '.')
 730                         goto checkpoint;
 731
 732                 if (lso == NULL) {
 733                         lso = lfsck_assistant_object_init(env,
 734                                 lfsck_dto2fid(dir), NULL,
 735                                 lfsck->li_pos_current.lp_oit_cookie, true);
 736                         if (IS_ERR(lso)) {
 737                                 if (bk->lb_param & LPF_FAILOUT)
 738                                         RETURN(PTR_ERR(lso));
 739
 740                                 lso = NULL;
 741                                 goto checkpoint;
 742                         }
 743                 }
 744
 745                 /* The type in the @ent structure may has been overwritten,
 746                  * so we need to pass the @type parameter independently. */
 747                 rc = lfsck_exec_dir(env, lfsck, lso, ent, type);
 748                 if (rc != 0 && bk->lb_param & LPF_FAILOUT)
 749                         GOTO(out, rc);
 750
 751 checkpoint:
 752                 rc = lfsck_checkpoint(env, lfsck);
 753                 if (rc != 0 && bk->lb_param & LPF_FAILOUT)
 754                         GOTO(out, rc);
 755
 756                 /* Rate control. */
 757                 lfsck_control_speed(lfsck);
 758                 if (unlikely(!thread_is_running(thread))) {
 759                         CDEBUG(D_LFSCK, "%s: scan dir exit for engine stop, "
 760                                "parent "DFID", cookie "LPX64"\n",
 761                                lfsck_lfsck2name(lfsck),
 762                                PFID(lfsck_dto2fid(dir)),
 763                                lfsck->li_cookie_dir);
 764                         GOTO(out, rc = 0);
 765                 }
 766
 767                 if (OBD_FAIL_CHECK(OBD_FAIL_LFSCK_FATAL2)) {
 768                         spin_lock(&lfsck->li_lock);
 769                         thread_set_flags(thread, SVC_STOPPING);
 770                         spin_unlock(&lfsck->li_lock);
 771                         GOTO(out, rc = -EINVAL);
 772                 }
 773
 774                 rc = iops->next(env, di);
 775         } while (rc == 0);
 776
 777         if (rc > 0 && !lfsck->li_oit_over)
 778                 lfsck_close_dir(env, lfsck, rc);
 779
 780         GOTO(out, rc);
 781
 782 out:
 783         if (lso != NULL)
 784                 lfsck_assistant_object_put(env, lso);
 785
 786         return rc;
 787 }
 788
 789 /**
 790  * Object-table based iteration engine.
 791  *
 792  * Object-table based iteration is the basic linear engine to scan all the
 793  * objects on current device in turn. For each object, it calls all the
 794  * registered LFSCK component(s)' API to perform related consistency
 795  * verification.
 796  *
 797  * It flushes related LFSCK trace files to disk via making checkpoint
 798  * periodically. Then if the server crashed or the LFSCK is paused, the
 799  * LFSCK can resume from the latest checkpoint.
 800  *
 801  * It also controls the whole LFSCK speed via lfsck_control_speed() to
 802  * avoid the server to become overload.
 803  *
 804  * \param[in] env       pointer to the thread context
 805  * \param[in] lfsck     pointer to the lfsck instance
 806  *
 807  * \retval              positive number if all objects have been scanned
 808  * \retval              0 if the iteration is stopped or paused
 809  * \retval              negative error number on failure
 810  */
 811 static int lfsck_master_oit_engine(const struct lu_env *env,
 812                                    struct lfsck_instance *lfsck)
 813 {
 814         struct lfsck_thread_info *info  = lfsck_env_info(env);
 815         const struct dt_it_ops   *iops  =
 816                                 &lfsck->li_obj_oit->do_index_ops->dio_it;
 817         struct dt_it             *di    = lfsck->li_di_oit;
 818         struct lu_fid            *fid   = &info->lti_fid;
 819         struct lfsck_bookmark    *bk    = &lfsck->li_bookmark_ram;
 820         struct ptlrpc_thread     *thread = &lfsck->li_thread;
 821         struct seq_server_site   *ss    = lfsck_dev_site(lfsck);
 822         __u32                    idx    = lfsck_dev_idx(lfsck);
 823         int                      rc;
 824         ENTRY;
 825
 826         if (unlikely(ss == NULL))
 827                 RETURN(-EIO);
 828
 829         do {
 830                 struct dt_object *target;
 831
 832                 if (lfsck->li_di_dir != NULL) {
 833                         rc = lfsck_master_dir_engine(env, lfsck);
 834                         if (rc <= 0)
 835                                 RETURN(rc);
 836                 }
 837
 838                 if (unlikely(lfsck->li_oit_over))
 839                         RETURN(1);
 840
 841                 if (CFS_FAIL_TIMEOUT(OBD_FAIL_LFSCK_DELAY1, cfs_fail_val) &&
 842                     unlikely(!thread_is_running(thread))) {
 843                         CDEBUG(D_LFSCK, "%s: OIT scan exit for engine stop, "
 844                                "cookie "LPU64"\n",
 845                                lfsck_lfsck2name(lfsck), iops->store(env, di));
 846
 847                         RETURN(0);
 848                 }
 849
 850                 if (OBD_FAIL_CHECK(OBD_FAIL_LFSCK_CRASH))
 851                         RETURN(0);
 852
 853                 lfsck->li_current_oit_processed = 1;
 854
 855                 if (!list_empty(&lfsck->li_list_lmv)) {
 856                         struct lfsck_lmv_unit *llu;
 857
 858                         spin_lock(&lfsck->li_lock);
 859                         llu = list_entry(lfsck->li_list_lmv.next,
 860                                          struct lfsck_lmv_unit, llu_link);
 861                         list_del_init(&llu->llu_link);
 862                         spin_unlock(&lfsck->li_lock);
 863
 864                         lfsck->li_lmv = &llu->llu_lmv;
 865                         lfsck->li_obj_dir = lfsck_object_get(llu->llu_obj);
 866                         rc = lfsck_open_dir(env, lfsck, 0);
 867                         if (rc == 0)
 868                                 rc = lfsck_master_dir_engine(env, lfsck);
 869
 870                         if (rc <= 0)
 871                                 RETURN(rc);
 872                 }
 873
 874                 lfsck->li_new_scanned++;
 875                 lfsck->li_pos_current.lp_oit_cookie = iops->store(env, di);
 876                 rc = iops->rec(env, di, (struct dt_rec *)fid, 0);
 877                 if (rc != 0) {
 878                         CDEBUG(D_LFSCK, "%s: OIT scan failed at rec(): "
 879                                "rc = %d\n", lfsck_lfsck2name(lfsck), rc);
 880                         lfsck_fail(env, lfsck, true);
 881                         if (rc < 0 && bk->lb_param & LPF_FAILOUT)
 882                                 RETURN(rc);
 883                         else
 884                                 goto checkpoint;
 885                 }
 886
 887                 if (unlikely(!fid_is_sane(fid))) {
 888                         CDEBUG(D_LFSCK, "%s: OIT scan find invalid FID "DFID
 889                                ", skip it\n",
 890                                lfsck_lfsck2name(lfsck), PFID(fid));
 891                         goto checkpoint;
 892                 }
 893
 894                 if (fid_is_idif(fid)) {
 895                         __u32 idx1 = fid_idif_ost_idx(fid);
 896
 897                         LASSERT(!lfsck->li_master);
 898
 899                         if (idx != idx1) {
 900                                 struct ost_id *oi = &info->lti_oi;
 901
 902                                 if (unlikely(idx1 != 0)) {
 903                                         CDEBUG(D_LFSCK, "%s: invalid IDIF "DFID
 904                                                ", not match device index %u\n",
 905                                                lfsck_lfsck2name(lfsck),
 906                                                PFID(fid), idx);
 907
 908                                         goto checkpoint;
 909                                 }
 910
 911                                 /* rebuild the IDIF with index to
 912                                  * avoid double instances for the
 913                                  * same object. */
 914                                 fid_to_ostid(fid, oi);
 915                                 ostid_to_fid(fid, oi, idx);
 916                         }
 917                 } else if (!fid_is_norm(fid) && !fid_is_igif(fid) &&
 918                            !fid_is_last_id(fid) &&
 919                            !lu_fid_eq(fid, &lfsck->li_global_root_fid)) {
 920
 921                         /* If the FID/object is only used locally and invisible
 922                          * to external nodes, then LFSCK will not handle it.
 923                          *
 924                          * dot_lustre sequence has been handled specially. */
 925                         goto checkpoint;
 926                 } else {
 927                         struct lu_seq_range *range = &info->lti_range;
 928
 929                         if (lfsck->li_master)
 930                                 fld_range_set_mdt(range);
 931                         else
 932                                 fld_range_set_ost(range);
 933                         rc = fld_local_lookup(env, ss->ss_server_fld,
 934                                               fid_seq(fid), range);
 935                         if (rc != 0 || range->lsr_index != idx) {
 936                                 /* Remote object will be handled by the LFSCK
 937                                  * instance on the MDT where the remote object
 938                                  * really resides on. */
 939                                 rc = 0;
 940                                 goto checkpoint;
 941                         }
 942                 }
 943
 944                 target = lfsck_object_find_bottom(env, lfsck, fid);
 945                 if (IS_ERR(target)) {
 946                         CDEBUG(D_LFSCK, "%s: OIT scan failed at find target "
 947                                DFID", cookie "LPU64": rc = %d\n",
 948                                lfsck_lfsck2name(lfsck), PFID(fid),
 949                                iops->store(env, di), rc);
 950                         lfsck_fail(env, lfsck, true);
 951                         if (bk->lb_param & LPF_FAILOUT)
 952                                 RETURN(PTR_ERR(target));
 953                         else
 954                                 goto checkpoint;
 955                 }
 956
 957                 if (dt_object_exists(target))
 958                         rc = lfsck_exec_oit(env, lfsck, target);
 959
 960                 lfsck_object_put(env, target);
 961                 if (rc != 0 && bk->lb_param & LPF_FAILOUT)
 962                         RETURN(rc);
 963
 964 checkpoint:
 965                 rc = lfsck_checkpoint(env, lfsck);
 966                 if (rc != 0 && bk->lb_param & LPF_FAILOUT)
 967                         RETURN(rc);
 968
 969                 /* Rate control. */
 970                 lfsck_control_speed(lfsck);
 971
 972                 if (OBD_FAIL_CHECK(OBD_FAIL_LFSCK_FATAL1)) {
 973                         spin_lock(&lfsck->li_lock);
 974                         thread_set_flags(thread, SVC_STOPPING);
 975                         spin_unlock(&lfsck->li_lock);
 976                         RETURN(-EINVAL);
 977                 }
 978
 979                 rc = iops->next(env, di);
 980                 if (unlikely(rc > 0))
 981                         lfsck->li_oit_over = 1;
 982                 else if (likely(rc == 0))
 983                         lfsck->li_current_oit_processed = 0;
 984
 985                 if (unlikely(!thread_is_running(thread))) {
 986                         CDEBUG(D_LFSCK, "%s: OIT scan exit for engine stop, "
 987                                "cookie "LPU64"\n", lfsck_lfsck2name(lfsck),
 988                                iops->store(env, di));
 989                         RETURN(0);
 990                 }
 991         } while (rc == 0 || lfsck->li_di_dir != NULL);
 992
 993         RETURN(rc);
 994 }
 995
 996 int lfsck_master_engine(void *args)
 997 {
 998         struct lfsck_thread_args *lta      = args;
 999         struct lu_env            *env      = &lta->lta_env;
1000         struct lfsck_instance    *lfsck    = lta->lta_lfsck;
1001         struct ptlrpc_thread     *thread   = &lfsck->li_thread;
1002         struct dt_object         *oit_obj  = lfsck->li_obj_oit;
1003         const struct dt_it_ops   *oit_iops = &oit_obj->do_index_ops->dio_it;
1004         struct dt_it             *oit_di;
1005         struct l_wait_info        lwi      = { 0 };
1006         int                       rc;
1007         ENTRY;
1008
1009         /* There will be some objects verification during the LFSCK start,
1010          * such as the subsequent lfsck_verify_lpf(). Trigger low layer OI
1011          * OI scrub before that to handle the potential inconsistence. */
1012         oit_di = oit_iops->init(env, oit_obj, lfsck->li_args_oit);
1013         if (IS_ERR(oit_di)) {
1014                 rc = PTR_ERR(oit_di);
1015                 CDEBUG(D_LFSCK, "%s: master engine fail to init iteration: "
1016                        "rc = %d\n", lfsck_lfsck2name(lfsck), rc);
1017
1018                 GOTO(fini_args, rc);
1019         }
1020
1021         if (lfsck->li_master &&
1022             (!list_empty(&lfsck->li_list_scan) ||
1023              !list_empty(&lfsck->li_list_double_scan))) {
1024                 rc = lfsck_verify_lpf(env, lfsck);
1025                 /* Fail to verify the .lustre/lost+found/MDTxxxx/ may be not
1026                  * fatal, because the .lustre/lost+found/ maybe not accessed
1027                  * by the LFSCK if it does not add orphans or others to such
1028                  * directory. So go ahead until hit failure when really uses
1029                  * the directory. */
1030                 if (rc != 0)
1031                         CDEBUG(D_LFSCK, "%s: master engine fail to verify the "
1032                                ".lustre/lost+found/, go ahead: rc = %d\n",
1033                                lfsck_lfsck2name(lfsck), rc);
1034         }
1035
1036         spin_lock(&lfsck->li_lock);
1037         lfsck->li_di_oit = oit_di;
1038         spin_unlock(&lfsck->li_lock);
1039         rc = lfsck_prep(env, lfsck, lta->lta_lsp);
1040         if (rc != 0)
1041                 GOTO(fini_oit, rc);
1042
1043         CDEBUG(D_LFSCK, "LFSCK entry: oit_flags = %#x, dir_flags = %#x, "
1044                "oit_cookie = "LPU64", dir_cookie = "LPX64", parent = "DFID
1045                ", pid = %d\n", lfsck->li_args_oit, lfsck->li_args_dir,
1046                lfsck->li_pos_checkpoint.lp_oit_cookie,
1047                lfsck->li_pos_checkpoint.lp_dir_cookie,
1048                PFID(&lfsck->li_pos_checkpoint.lp_dir_parent),
1049                current_pid());
1050
1051         spin_lock(&lfsck->li_lock);
1052         thread_set_flags(thread, SVC_RUNNING);
1053         spin_unlock(&lfsck->li_lock);
1054         wake_up_all(&thread->t_ctl_waitq);
1055
1056         l_wait_event(thread->t_ctl_waitq,
1057                      lfsck->li_start_unplug ||
1058                      !thread_is_running(thread),
1059                      &lwi);
1060         if (!thread_is_running(thread))
1061                 GOTO(fini_oit, rc = 0);
1062
1063         if (!list_empty(&lfsck->li_list_scan) ||
1064             list_empty(&lfsck->li_list_double_scan))
1065                 rc = lfsck_master_oit_engine(env, lfsck);
1066         else
1067                 rc = 1;
1068
1069         lfsck_pos_fill(env, lfsck, &lfsck->li_pos_checkpoint, false);
1070         CDEBUG(D_LFSCK, "LFSCK exit: oit_flags = %#x, dir_flags = %#x, "
1071                "oit_cookie = "LPU64", dir_cookie = "LPX64", parent = "DFID
1072                ", pid = %d, rc = %d\n", lfsck->li_args_oit, lfsck->li_args_dir,
1073                lfsck->li_pos_checkpoint.lp_oit_cookie,
1074                lfsck->li_pos_checkpoint.lp_dir_cookie,
1075                PFID(&lfsck->li_pos_checkpoint.lp_dir_parent),
1076                current_pid(), rc);
1077
1078         if (!OBD_FAIL_CHECK(OBD_FAIL_LFSCK_CRASH))
1079                 rc = lfsck_post(env, lfsck, rc);
1080         else
1081                 lfsck_close_dir(env, lfsck, rc);
1082
1083 fini_oit:
1084         lfsck_di_oit_put(env, lfsck);
1085         oit_iops->fini(env, oit_di);
1086         if (rc == 1) {
1087                 if (!list_empty(&lfsck->li_list_double_scan))
1088                         rc = lfsck_double_scan(env, lfsck);
1089                 else
1090                         rc = 0;
1091         } else {
1092                 lfsck_quit(env, lfsck);
1093         }
1094
1095         /* XXX: Purge the pinned objects in the future. */
1096
1097 fini_args:
1098         spin_lock(&lfsck->li_lock);
1099         thread_set_flags(thread, SVC_STOPPED);
1100         spin_unlock(&lfsck->li_lock);
1101         wake_up_all(&thread->t_ctl_waitq);
1102         lfsck_thread_args_fini(lta);
1103         return rc;
1104 }
1105
1106 static inline bool lfsck_assistant_req_empty(struct lfsck_assistant_data *lad)
1107 {
1108         bool empty = false;
1109
1110         spin_lock(&lad->lad_lock);
1111         if (list_empty(&lad->lad_req_list))
1112                 empty = true;
1113         spin_unlock(&lad->lad_lock);
1114
1115         return empty;
1116 }
1117
1118 /**
1119  * Query the LFSCK status from the instatnces on remote servers.
1120  *
1121  * The LFSCK assistant thread queries the LFSCK instances on other
1122  * servers (MDT/OST) about their status, such as whether they have
1123  * finished the phase1/phase2 scanning or not, and so on.
1124  *
1125  * \param[in] env       pointer to the thread context
1126  * \param[in] com       pointer to the lfsck component
1127  *
1128  * \retval              0 for success
1129  * \retval              negative error number on failure
1130  */
1131 static int lfsck_assistant_query_others(const struct lu_env *env,
1132                                         struct lfsck_component *com)
1133 {
1134         struct lfsck_thread_info          *info  = lfsck_env_info(env);
1135         struct lfsck_request              *lr    = &info->lti_lr;
1136         struct lfsck_async_interpret_args *laia  = &info->lti_laia;
1137         struct lfsck_instance             *lfsck = com->lc_lfsck;
1138         struct lfsck_assistant_data       *lad   = com->lc_data;
1139         struct ptlrpc_request_set         *set;
1140         struct lfsck_tgt_descs            *ltds;
1141         struct lfsck_tgt_desc             *ltd;
1142         struct list_head                  *phase_head;
1143         int                                rc    = 0;
1144         int                                rc1   = 0;
1145         ENTRY;
1146
1147         set = ptlrpc_prep_set();
1148         if (set == NULL)
1149                 RETURN(-ENOMEM);
1150
1151         lad->lad_touch_gen++;
1152         memset(lr, 0, sizeof(*lr));
1153         lr->lr_event = LE_QUERY;
1154         lr->lr_active = com->lc_type;
1155
1156         memset(laia, 0, sizeof(*laia));
1157         laia->laia_com = com;
1158         laia->laia_lr = lr;
1159
1160         if (!list_empty(&lad->lad_mdt_phase1_list)) {
1161                 ltds = &lfsck->li_mdt_descs;
1162                 lr->lr_flags = 0;
1163                 phase_head = &lad->lad_mdt_phase1_list;
1164         } else if (com->lc_type != LFSCK_TYPE_LAYOUT) {
1165                 goto out;
1166         } else {
1167
1168 again:
1169                 ltds = &lfsck->li_ost_descs;
1170                 lr->lr_flags = LEF_TO_OST;
1171                 phase_head = &lad->lad_ost_phase1_list;
1172         }
1173
1174         laia->laia_ltds = ltds;
1175         spin_lock(&ltds->ltd_lock);
1176         while (!list_empty(phase_head)) {
1177                 struct list_head *phase_list;
1178                 __u32            *gen;
1179
1180                 if (com->lc_type == LFSCK_TYPE_LAYOUT) {
1181                         ltd = list_entry(phase_head->next,
1182                                          struct lfsck_tgt_desc,
1183                                          ltd_layout_phase_list);
1184                         phase_list = &ltd->ltd_layout_phase_list;
1185                         gen = &ltd->ltd_layout_gen;
1186                 } else {
1187                         ltd = list_entry(phase_head->next,
1188                                          struct lfsck_tgt_desc,
1189                                          ltd_namespace_phase_list);
1190                         phase_list = &ltd->ltd_namespace_phase_list;
1191                         gen = &ltd->ltd_namespace_gen;
1192                 }
1193
1194                 if (*gen == lad->lad_touch_gen)
1195                         break;
1196
1197                 *gen = lad->lad_touch_gen;
1198                 list_move_tail(phase_list, phase_head);
1199                 atomic_inc(&ltd->ltd_ref);
1200                 laia->laia_ltd = ltd;
1201                 spin_unlock(&ltds->ltd_lock);
1202                 rc = lfsck_async_request(env, ltd->ltd_exp, lr, set,
1203                                          lfsck_async_interpret_common,
1204                                          laia, LFSCK_QUERY);
1205                 if (rc != 0) {
1206                         CDEBUG(D_LFSCK, "%s: LFSCK assistant fail to query "
1207                                "%s %x for %s: rc = %d\n",
1208                                lfsck_lfsck2name(lfsck),
1209                                (lr->lr_flags & LEF_TO_OST) ? "OST" : "MDT",
1210                                ltd->ltd_index, lad->lad_name, rc);
1211                         lfsck_tgt_put(ltd);
1212                         rc1 = rc;
1213                 }
1214                 spin_lock(&ltds->ltd_lock);
1215         }
1216         spin_unlock(&ltds->ltd_lock);
1217
1218         rc = ptlrpc_set_wait(set);
1219         if (rc < 0) {
1220                 ptlrpc_set_destroy(set);
1221                 RETURN(rc);
1222         }
1223
1224         if (com->lc_type == LFSCK_TYPE_LAYOUT && !(lr->lr_flags & LEF_TO_OST) &&
1225             list_empty(&lad->lad_mdt_phase1_list))
1226                 goto again;
1227
1228 out:
1229         ptlrpc_set_destroy(set);
1230
1231         RETURN(rc1 != 0 ? rc1 : rc);
1232 }
1233
1234 /**
1235  * Notify the LFSCK event to the instances on remote servers.
1236  *
1237  * The LFSCK assistant thread notifies the LFSCK instances on other
1238  * servers (MDT/OST) about some events, such as start new scanning,
1239  * stop the scanning, this LFSCK instance will exit, and so on.
1240  *
1241  * \param[in] env       pointer to the thread context
1242  * \param[in] com       pointer to the lfsck component
1243  * \param[in] lr        pointer to the LFSCK event request
1244  *
1245  * \retval              0 for success
1246  * \retval              negative error number on failure
1247  */
1248 static int lfsck_assistant_notify_others(const struct lu_env *env,
1249                                          struct lfsck_component *com,
1250                                          struct lfsck_request *lr)
1251 {
1252         struct lfsck_thread_info          *info  = lfsck_env_info(env);
1253         struct lfsck_async_interpret_args *laia  = &info->lti_laia;
1254         struct lfsck_instance             *lfsck = com->lc_lfsck;
1255         struct lfsck_assistant_data       *lad   = com->lc_data;
1256         struct lfsck_bookmark             *bk    = &lfsck->li_bookmark_ram;
1257         struct ptlrpc_request_set         *set;
1258         struct lfsck_tgt_descs            *ltds;
1259         struct lfsck_tgt_desc             *ltd;
1260         struct lfsck_tgt_desc             *next;
1261         __u32                              idx;
1262         int                                rc    = 0;
1263         int                                rc1   = 0;
1264         ENTRY;
1265
1266         set = ptlrpc_prep_set();
1267         if (set == NULL)
1268                 RETURN(-ENOMEM);
1269
1270         lr->lr_index = lfsck_dev_idx(lfsck);
1271         lr->lr_active = com->lc_type;
1272
1273         memset(laia, 0, sizeof(*laia));
1274         laia->laia_com = com;
1275         laia->laia_lr = lr;
1276
1277         switch (lr->lr_event) {
1278         case LE_START:
1279                 if (com->lc_type != LFSCK_TYPE_LAYOUT)
1280                         goto next;
1281
1282                 lr->lr_valid = LSV_SPEED_LIMIT | LSV_ERROR_HANDLE | LSV_DRYRUN;
1283                 lr->lr_speed = bk->lb_speed_limit;
1284                 lr->lr_version = bk->lb_version;
1285                 lr->lr_param |= bk->lb_param;
1286                 lr->lr_async_windows = bk->lb_async_windows;
1287                 lr->lr_flags = LEF_TO_OST;
1288
1289                 /* Notify OSTs firstly, then handle other MDTs if needed. */
1290                 ltds = &lfsck->li_ost_descs;
1291                 laia->laia_ltds = ltds;
1292                 down_read(&ltds->ltd_rw_sem);
1293                 cfs_foreach_bit(ltds->ltd_tgts_bitmap, idx) {
1294                         ltd = lfsck_tgt_get(ltds, idx);
1295                         LASSERT(ltd != NULL);
1296
1297                         laia->laia_ltd = ltd;
1298                         rc = lfsck_async_request(env, ltd->ltd_exp, lr, set,
1299                                         lfsck_async_interpret_common,
1300                                         laia, LFSCK_NOTIFY);
1301                         if (rc != 0) {
1302                                 lfsck_lad_set_bitmap(env, com, idx);
1303                                 CDEBUG(D_LFSCK, "%s: LFSCK assistant fail to "
1304                                        "notify OST %x for %s start: rc = %d\n",
1305                                        lfsck_lfsck2name(lfsck), idx,
1306                                        lad->lad_name, rc);
1307                                 lfsck_tgt_put(ltd);
1308                         }
1309                 }
1310                 up_read(&ltds->ltd_rw_sem);
1311
1312                 /* Sync up */
1313                 rc = ptlrpc_set_wait(set);
1314                 if (rc < 0) {
1315                         ptlrpc_set_destroy(set);
1316                         RETURN(rc);
1317                 }
1318
1319 next:
1320                 if (!(bk->lb_param & LPF_ALL_TGT))
1321                         break;
1322
1323                 /* link other MDT targets locallly. */
1324                 ltds = &lfsck->li_mdt_descs;
1325                 spin_lock(&ltds->ltd_lock);
1326                 if (com->lc_type == LFSCK_TYPE_LAYOUT) {
1327                         cfs_foreach_bit(ltds->ltd_tgts_bitmap, idx) {
1328                                 ltd = lfsck_ltd2tgt(ltds, idx);
1329                                 LASSERT(ltd != NULL);
1330
1331                                 if (!list_empty(&ltd->ltd_layout_list))
1332                                         continue;
1333
1334                                 list_add_tail(&ltd->ltd_layout_list,
1335                                               &lad->lad_mdt_list);
1336                                 list_add_tail(&ltd->ltd_layout_phase_list,
1337                                               &lad->lad_mdt_phase1_list);
1338                         }
1339                 } else {
1340                         cfs_foreach_bit(ltds->ltd_tgts_bitmap, idx) {
1341                                 ltd = lfsck_ltd2tgt(ltds, idx);
1342                                 LASSERT(ltd != NULL);
1343
1344                                 if (!list_empty(&ltd->ltd_namespace_list))
1345                                         continue;
1346
1347                                 list_add_tail(&ltd->ltd_namespace_list,
1348                                               &lad->lad_mdt_list);
1349                                 list_add_tail(&ltd->ltd_namespace_phase_list,
1350                                               &lad->lad_mdt_phase1_list);
1351                         }
1352                 }
1353                 spin_unlock(&ltds->ltd_lock);
1354                 break;
1355         case LE_STOP:
1356         case LE_PHASE2_DONE:
1357         case LE_PEER_EXIT: {
1358                 struct list_head *phase_head;
1359
1360                 /* Handle other MDTs firstly if needed, then notify the OSTs. */
1361                 if (bk->lb_param & LPF_ALL_TGT) {
1362                         phase_head = &lad->lad_mdt_list;
1363                         ltds = &lfsck->li_mdt_descs;
1364                         if (lr->lr_event == LE_STOP) {
1365                                 /* unlink other MDT targets locallly. */
1366                                 spin_lock(&ltds->ltd_lock);
1367                                 if (com->lc_type == LFSCK_TYPE_LAYOUT) {
1368                                         list_for_each_entry_safe(ltd, next,
1369                                                 phase_head, ltd_layout_list) {
1370                                                 list_del_init(
1371                                                 &ltd->ltd_layout_phase_list);
1372                                                 list_del_init(
1373                                                 &ltd->ltd_layout_list);
1374                                         }
1375                                 } else {
1376                                         list_for_each_entry_safe(ltd, next,
1377                                                         phase_head,
1378                                                         ltd_namespace_list) {
1379                                                 list_del_init(
1380                                                 &ltd->ltd_namespace_phase_list);
1381                                                 list_del_init(
1382                                                 &ltd->ltd_namespace_list);
1383                                         }
1384                                 }
1385                                 spin_unlock(&ltds->ltd_lock);
1386
1387                                 if (com->lc_type != LFSCK_TYPE_LAYOUT)
1388                                         break;
1389
1390                                 lr->lr_flags |= LEF_TO_OST;
1391                                 phase_head = &lad->lad_ost_list;
1392                                 ltds = &lfsck->li_ost_descs;
1393                         } else {
1394                                 lr->lr_flags &= ~LEF_TO_OST;
1395                         }
1396                 } else if (com->lc_type != LFSCK_TYPE_LAYOUT) {
1397                         break;
1398                 } else {
1399                         lr->lr_flags |= LEF_TO_OST;
1400                         phase_head = &lad->lad_ost_list;
1401                         ltds = &lfsck->li_ost_descs;
1402                 }
1403
1404 again:
1405                 laia->laia_ltds = ltds;
1406                 spin_lock(&ltds->ltd_lock);
1407                 while (!list_empty(phase_head)) {
1408                         if (com->lc_type == LFSCK_TYPE_LAYOUT) {
1409                                 ltd = list_entry(phase_head->next,
1410                                                  struct lfsck_tgt_desc,
1411                                                  ltd_layout_list);
1412                                 if (!list_empty(&ltd->ltd_layout_phase_list))
1413                                         list_del_init(
1414                                                 &ltd->ltd_layout_phase_list);
1415                                 list_del_init(&ltd->ltd_layout_list);
1416                         } else {
1417                                 ltd = list_entry(phase_head->next,
1418                                                  struct lfsck_tgt_desc,
1419                                                  ltd_namespace_list);
1420                                 if (!list_empty(&ltd->ltd_namespace_phase_list))
1421                                         list_del_init(
1422                                                 &ltd->ltd_namespace_phase_list);
1423                                 list_del_init(&ltd->ltd_namespace_list);
1424                         }
1425                         atomic_inc(&ltd->ltd_ref);
1426                         laia->laia_ltd = ltd;
1427                         spin_unlock(&ltds->ltd_lock);
1428                         rc = lfsck_async_request(env, ltd->ltd_exp, lr, set,
1429                                         lfsck_async_interpret_common,
1430                                         laia, LFSCK_NOTIFY);
1431                         if (rc != 0) {
1432                                 CDEBUG(D_LFSCK, "%s: LFSCK assistant fail to "
1433                                        "notify %s %x for %s stop/phase2_done/"
1434                                        "peer_exit: rc = %d\n",
1435                                        lfsck_lfsck2name(lfsck),
1436                                        (lr->lr_flags & LEF_TO_OST) ?
1437                                        "OST" : "MDT", ltd->ltd_index,
1438                                        lad->lad_name, rc);
1439                                 lfsck_tgt_put(ltd);
1440                         }
1441                         spin_lock(&ltds->ltd_lock);
1442                 }
1443                 spin_unlock(&ltds->ltd_lock);
1444
1445                 rc = ptlrpc_set_wait(set);
1446                 if (rc < 0) {
1447                         ptlrpc_set_destroy(set);
1448                         RETURN(rc);
1449                 }
1450
1451                 if (com->lc_type == LFSCK_TYPE_LAYOUT &&
1452                     !(lr->lr_flags & LEF_TO_OST)) {
1453                         lr->lr_flags |= LEF_TO_OST;
1454                         phase_head = &lad->lad_ost_list;
1455                         ltds = &lfsck->li_ost_descs;
1456                         goto again;
1457                 }
1458                 break;
1459         }
1460         case LE_PHASE1_DONE:
1461                 lad->lad_ops->la_sync_failures(env, com, lr);
1462                 lad->lad_touch_gen++;
1463                 ltds = &lfsck->li_mdt_descs;
1464                 laia->laia_ltds = ltds;
1465                 spin_lock(&ltds->ltd_lock);
1466                 while (!list_empty(&lad->lad_mdt_list)) {
1467                         struct list_head *list;
1468                         __u32            *gen;
1469
1470                         if (com->lc_type == LFSCK_TYPE_LAYOUT) {
1471                                 ltd = list_entry(lad->lad_mdt_list.next,
1472                                                  struct lfsck_tgt_desc,
1473                                                  ltd_layout_list);
1474                                 list = &ltd->ltd_layout_list;
1475                                 gen = &ltd->ltd_layout_gen;
1476                         } else {
1477                                 struct lfsck_namespace *ns = com->lc_file_ram;
1478
1479                                 ltd = list_entry(lad->lad_mdt_list.next,
1480                                                  struct lfsck_tgt_desc,
1481                                                  ltd_namespace_list);
1482                                 list = &ltd->ltd_namespace_list;
1483                                 gen = &ltd->ltd_namespace_gen;
1484                                 lr->lr_flags2 = ns->ln_flags & ~LF_INCOMPLETE;
1485                         }
1486
1487                         if (*gen == lad->lad_touch_gen)
1488                                 break;
1489
1490                         *gen = lad->lad_touch_gen;
1491                         list_move_tail(list, &lad->lad_mdt_list);
1492                         if (ltd->ltd_synced_failures)
1493                                 continue;
1494
1495                         atomic_inc(&ltd->ltd_ref);
1496                         laia->laia_ltd = ltd;
1497                         spin_unlock(&ltds->ltd_lock);
1498                         rc = lfsck_async_request(env, ltd->ltd_exp, lr, set,
1499                                         lfsck_async_interpret_common,
1500                                         laia, LFSCK_NOTIFY);
1501                         if (rc != 0) {
1502                                 CDEBUG(D_LFSCK, "%s: LFSCK assistant fail to "
1503                                        "notify MDT %x for %s phase1 done: "
1504                                        "rc = %d\n", lfsck_lfsck2name(lfsck),
1505                                        ltd->ltd_index, lad->lad_name, rc);
1506                                 lfsck_tgt_put(ltd);
1507                         }
1508                         spin_lock(&ltds->ltd_lock);
1509                 }
1510                 spin_unlock(&ltds->ltd_lock);
1511                 break;
1512         default:
1513                 CDEBUG(D_LFSCK, "%s: LFSCK assistant unexpected LFSCK event: "
1514                        "rc = %d\n", lfsck_lfsck2name(lfsck), lr->lr_event);
1515                 rc = -EINVAL;
1516                 break;
1517         }
1518
1519         rc1 = ptlrpc_set_wait(set);
1520         ptlrpc_set_destroy(set);
1521
1522         RETURN(rc != 0 ? rc : rc1);
1523 }
1524
1525 /**
1526  * The LFSCK assistant thread is triggered by the LFSCK main engine.
1527  * They co-work together as an asynchronous pipeline: the LFSCK main
1528  * engine scans the system and pre-fetches the objects, attributes,
1529  * or name entries, etc, and pushes them into the pipeline as input
1530  * requests for the LFSCK assistant thread; on the other end of the
1531  * pipeline, the LFSCK assistant thread performs the real check and
1532  * repair for every request from the main engine.
1533  *
1534  * Generally, the assistant engine may be blocked when check/repair
1535  * something, so the LFSCK main engine will run some faster. On the
1536  * other hand, the LFSCK main engine will drive multiple assistant
1537  * threads in parallel, means for each LFSCK component on the master
1538  * (such as layout LFSCK, namespace LFSCK), there is an independent
1539  * LFSCK assistant thread. So under such 1:N multiple asynchronous
1540  * pipelines mode, the whole LFSCK performance will be much better
1541  * than check/repair everything by the LFSCK main engine itself.
1542  */
1543 int lfsck_assistant_engine(void *args)
1544 {
1545         struct lfsck_thread_args          *lta     = args;
1546         struct lu_env                     *env     = &lta->lta_env;
1547         struct lfsck_component            *com     = lta->lta_com;
1548         struct lfsck_instance             *lfsck   = lta->lta_lfsck;
1549         struct lfsck_bookmark             *bk      = &lfsck->li_bookmark_ram;
1550         struct lfsck_position             *pos     = &com->lc_pos_start;
1551         struct lfsck_thread_info          *info    = lfsck_env_info(env);
1552         struct lfsck_request              *lr      = &info->lti_lr;
1553         struct lfsck_assistant_data       *lad     = com->lc_data;
1554         struct ptlrpc_thread              *mthread = &lfsck->li_thread;
1555         struct ptlrpc_thread              *athread = &lad->lad_thread;
1556         struct lfsck_assistant_operations *lao     = lad->lad_ops;
1557         struct lfsck_assistant_req        *lar;
1558         struct l_wait_info                 lwi     = { 0 };
1559         int                                rc      = 0;
1560         int                                rc1     = 0;
1561         int                                rc2;
1562         ENTRY;
1563
1564         CDEBUG(D_LFSCK, "%s: %s LFSCK assistant thread start\n",
1565                lfsck_lfsck2name(lfsck), lad->lad_name);
1566
1567         memset(lr, 0, sizeof(*lr));
1568         lr->lr_event = LE_START;
1569         if (pos->lp_oit_cookie <= 1)
1570                 lr->lr_param = LPF_RESET;
1571         rc = lfsck_assistant_notify_others(env, com, lr);
1572         if (rc != 0) {
1573                 CDEBUG(D_LFSCK, "%s: LFSCK assistant fail to notify others "
1574                        "to start %s: rc = %d\n",
1575                        lfsck_lfsck2name(lfsck), lad->lad_name, rc);
1576                 GOTO(fini, rc);
1577         }
1578
1579         spin_lock(&lad->lad_lock);
1580         lad->lad_task = current;
1581         thread_set_flags(athread, SVC_RUNNING);
1582         spin_unlock(&lad->lad_lock);
1583         wake_up_all(&mthread->t_ctl_waitq);
1584
1585         while (1) {
1586                 while (!list_empty(&lad->lad_req_list)) {
1587                         bool wakeup = false;
1588
1589                         if (unlikely(lad->lad_exit ||
1590                                      !thread_is_running(mthread)))
1591                                 GOTO(cleanup1, rc = lad->lad_post_result);
1592
1593                         lar = list_entry(lad->lad_req_list.next,
1594                                          struct lfsck_assistant_req,
1595                                          lar_list);
1596                         /* Only the lfsck_assistant_engine thread itself can
1597                          * remove the "lar" from the head of the list, LFSCK
1598                          * engine thread only inserts other new "lar" at the
1599                          * end of the list. So it is safe to handle current
1600                          * "lar" without the spin_lock. */
1601                         rc = lao->la_handler_p1(env, com, lar);
1602                         spin_lock(&lad->lad_lock);
1603                         list_del_init(&lar->lar_list);
1604                         lad->lad_prefetched--;
1605                         /* Wake up the main engine thread only when the list
1606                          * is empty or half of the prefetched items have been
1607                          * handled to avoid too frequent thread schedule. */
1608                         if (lad->lad_prefetched <= (bk->lb_async_windows / 2))
1609                                 wakeup = true;
1610                         spin_unlock(&lad->lad_lock);
1611                         if (wakeup)
1612                                 wake_up_all(&mthread->t_ctl_waitq);
1613
1614                         lao->la_req_fini(env, lar);
1615                         if (rc < 0 && bk->lb_param & LPF_FAILOUT)
1616                                 GOTO(cleanup1, rc);
1617                 }
1618
1619                 l_wait_event(athread->t_ctl_waitq,
1620                              !lfsck_assistant_req_empty(lad) ||
1621                              lad->lad_exit ||
1622                              lad->lad_to_post ||
1623                              lad->lad_to_double_scan,
1624                              &lwi);
1625
1626                 if (unlikely(lad->lad_exit))
1627                         GOTO(cleanup1, rc = lad->lad_post_result);
1628
1629                 if (!list_empty(&lad->lad_req_list))
1630                         continue;
1631
1632                 if (lad->lad_to_post) {
1633                         CDEBUG(D_LFSCK, "%s: %s LFSCK assistant thread post\n",
1634                                lfsck_lfsck2name(lfsck), lad->lad_name);
1635
1636                         if (unlikely(lad->lad_exit))
1637                                 GOTO(cleanup1, rc = lad->lad_post_result);
1638
1639                         lad->lad_to_post = 0;
1640                         LASSERT(lad->lad_post_result > 0);
1641
1642                         /* Wakeup the master engine to go ahead. */
1643                         wake_up_all(&mthread->t_ctl_waitq);
1644
1645                         memset(lr, 0, sizeof(*lr));
1646                         lr->lr_event = LE_PHASE1_DONE;
1647                         lr->lr_status = lad->lad_post_result;
1648                         rc = lfsck_assistant_notify_others(env, com, lr);
1649
1650                         CDEBUG(D_LFSCK, "%s: LFSCK assistant notified "
1651                                "others for %s post: rc = %d\n",
1652                                lfsck_lfsck2name(lfsck),
1653                                lad->lad_name, rc);
1654                 }
1655
1656                 if (lad->lad_to_double_scan) {
1657                         lad->lad_to_double_scan = 0;
1658                         atomic_inc(&lfsck->li_double_scan_count);
1659                         lad->lad_in_double_scan = 1;
1660                         wake_up_all(&mthread->t_ctl_waitq);
1661
1662                         com->lc_new_checked = 0;
1663                         com->lc_new_scanned = 0;
1664                         com->lc_time_last_checkpoint = cfs_time_current();
1665                         com->lc_time_next_checkpoint =
1666                                 com->lc_time_last_checkpoint +
1667                                 cfs_time_seconds(LFSCK_CHECKPOINT_INTERVAL);
1668
1669                         CDEBUG(D_LFSCK, "%s: LFSCK assistant sync before "
1670                                "the second-stage scaning\n",
1671                                lfsck_lfsck2name(lfsck));
1672
1673                         /* Flush async updates before handling orphan. */
1674                         rc2 = dt_sync(env, lfsck->li_next);
1675
1676                         CDEBUG(D_LFSCK, "%s: LFSCK assistant phase2 "
1677                                "scan start, synced: rc = %d\n",
1678                                lfsck_lfsck2name(lfsck), rc2);
1679
1680                         if (OBD_FAIL_CHECK(OBD_FAIL_LFSCK_NO_DOUBLESCAN))
1681                                 GOTO(cleanup2, rc = 0);
1682
1683                         while (lad->lad_in_double_scan) {
1684                                 rc = lfsck_assistant_query_others(env, com);
1685                                 if (lfsck_phase2_next_ready(lad))
1686                                         goto p2_next;
1687
1688                                 if (rc < 0)
1689                                         GOTO(cleanup2, rc);
1690
1691                                 /* Pull LFSCK status on related targets once
1692                                  * per 30 seconds if we are not notified. */
1693                                 lwi = LWI_TIMEOUT_INTERVAL(cfs_time_seconds(30),
1694                                                            cfs_time_seconds(1),
1695                                                            NULL, NULL);
1696                                 rc = l_wait_event(athread->t_ctl_waitq,
1697                                         lfsck_phase2_next_ready(lad) ||
1698                                         lad->lad_exit ||
1699                                         !thread_is_running(mthread),
1700                                         &lwi);
1701
1702                                 if (unlikely(lad->lad_exit ||
1703                                              !thread_is_running(mthread)))
1704                                         GOTO(cleanup2, rc = 0);
1705
1706                                 if (rc == -ETIMEDOUT)
1707                                         continue;
1708
1709                                 if (rc < 0)
1710                                         GOTO(cleanup2, rc);
1711
1712 p2_next:
1713                                 rc = lao->la_handler_p2(env, com);
1714                                 if (rc != 0)
1715                                         GOTO(cleanup2, rc);
1716
1717                                 if (unlikely(lad->lad_exit ||
1718                                              !thread_is_running(mthread)))
1719                                         GOTO(cleanup2, rc = 0);
1720                         }
1721                 }
1722         }
1723
1724 cleanup1:
1725         /* Cleanup the unfinished requests. */
1726         spin_lock(&lad->lad_lock);
1727         if (rc < 0)
1728                 lad->lad_assistant_status = rc;
1729
1730         if (lad->lad_exit && lad->lad_post_result <= 0)
1731                 lao->la_fill_pos(env, com, &lfsck->li_pos_checkpoint);
1732
1733         while (!list_empty(&lad->lad_req_list)) {
1734                 lar = list_entry(lad->lad_req_list.next,
1735                                  struct lfsck_assistant_req,
1736                                  lar_list);
1737                 list_del_init(&lar->lar_list);
1738                 lad->lad_prefetched--;
1739                 spin_unlock(&lad->lad_lock);
1740                 lao->la_req_fini(env, lar);
1741                 spin_lock(&lad->lad_lock);
1742         }
1743         spin_unlock(&lad->lad_lock);
1744
1745         LASSERTF(lad->lad_prefetched == 0, "unmatched prefeteched objs %d\n",
1746                  lad->lad_prefetched);
1747
1748 cleanup2:
1749         memset(lr, 0, sizeof(*lr));
1750         if (rc > 0) {
1751                 lr->lr_event = LE_PHASE2_DONE;
1752                 lr->lr_status = rc;
1753         } else if (rc == 0) {
1754                 if (lfsck->li_flags & LPF_ALL_TGT) {
1755                         lr->lr_event = LE_STOP;
1756                         lr->lr_status = LS_STOPPED;
1757                 } else {
1758                         lr->lr_event = LE_PEER_EXIT;
1759                         switch (lfsck->li_status) {
1760                         case LS_PAUSED:
1761                         case LS_CO_PAUSED:
1762                                 lr->lr_status = LS_CO_PAUSED;
1763                                 break;
1764                         case LS_STOPPED:
1765                         case LS_CO_STOPPED:
1766                                 lr->lr_status = LS_CO_STOPPED;
1767                                 break;
1768                         default:
1769                                 CDEBUG(D_LFSCK, "%s: LFSCK assistant unknown "
1770                                        "status: rc = %d\n",
1771                                        lfsck_lfsck2name(lfsck),
1772                                        lfsck->li_status);
1773                                 lr->lr_status = LS_CO_FAILED;
1774                                 break;
1775                         }
1776                 }
1777         } else {
1778                 if (lfsck->li_flags & LPF_ALL_TGT) {
1779                         lr->lr_event = LE_STOP;
1780                         lr->lr_status = LS_FAILED;
1781                 } else {
1782                         lr->lr_event = LE_PEER_EXIT;
1783                         lr->lr_status = LS_CO_FAILED;
1784                 }
1785         }
1786
1787         rc1 = lfsck_assistant_notify_others(env, com, lr);
1788         if (rc1 != 0) {
1789                 CDEBUG(D_LFSCK, "%s: LFSCK assistant failed to notify "
1790                        "others for %s quit: rc = %d\n",
1791                        lfsck_lfsck2name(lfsck), lad->lad_name, rc1);
1792                 rc = rc1;
1793         }
1794
1795         CDEBUG(D_LFSCK, "%s: LFSCK assistant sync before exit\n",
1796                lfsck_lfsck2name(lfsck));
1797
1798         /* Flush async updates before exit. */
1799         rc2 = dt_sync(env, lfsck->li_next);
1800
1801         CDEBUG(D_LFSCK, "%s: LFSCK assistant synced before exit: rc = %d\n",
1802                lfsck_lfsck2name(lfsck), rc2);
1803
1804         /* Under force exit case, some requests may be just freed without
1805          * verification, those objects should be re-handled when next run.
1806          * So not update the on-disk trace file under such case. */
1807         if (lad->lad_in_double_scan) {
1808                 if (!lad->lad_exit)
1809                         rc1 = lao->la_double_scan_result(env, com, rc);
1810
1811                 CDEBUG(D_LFSCK, "%s: LFSCK assistant phase2 scan "
1812                        "finished: rc = %d\n",
1813                        lfsck_lfsck2name(lfsck), rc1 != 0 ? rc1 : rc);
1814         }
1815
1816 fini:
1817         if (lad->lad_in_double_scan)
1818                 atomic_dec(&lfsck->li_double_scan_count);
1819
1820         spin_lock(&lad->lad_lock);
1821         lad->lad_assistant_status = (rc1 != 0 ? rc1 : rc);
1822         thread_set_flags(athread, SVC_STOPPED);
1823         wake_up_all(&mthread->t_ctl_waitq);
1824         lad->lad_task = NULL;
1825         spin_unlock(&lad->lad_lock);
1826
1827         CDEBUG(D_LFSCK, "%s: %s LFSCK assistant thread exit: rc = %d\n",
1828                lfsck_lfsck2name(lfsck), lad->lad_name,
1829                lad->lad_assistant_status);
1830
1831         lfsck_thread_args_fini(lta);
1832
1833         return rc;
1834 }