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LU-5519 lfsck: repair master LMV for striped directory
[fs/lustre-release.git] / 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) 2012, 2013, 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_update_lma(const struct lu_env *env,
97                             struct lfsck_instance *lfsck, struct dt_object *obj)
98 {
99         struct lfsck_thread_info        *info   = lfsck_env_info(env);
100         struct lfsck_bookmark           *bk     = &lfsck->li_bookmark_ram;
101         struct dt_device                *dt     = lfsck->li_bottom;
102         struct lustre_mdt_attrs         *lma    = &info->lti_lma;
103         struct lu_buf                   *buf;
104         struct thandle                  *th;
105         int                              fl;
106         int                              rc;
107         ENTRY;
108
109         if (bk->lb_param & LPF_DRYRUN)
110                 RETURN(0);
111
112         buf = lfsck_buf_get(env, info->lti_lma_old, LMA_OLD_SIZE);
113         rc = dt_xattr_get(env, obj, buf, XATTR_NAME_LMA, BYPASS_CAPA);
114         if (rc < 0) {
115                 if (rc != -ENODATA)
116                         RETURN(rc);
117
118                 fl = LU_XATTR_CREATE;
119                 lustre_lma_init(lma, lfsck_dto2fid(obj), LMAC_FID_ON_OST, 0);
120         } else {
121                 if (rc != LMA_OLD_SIZE && rc != sizeof(struct lustre_mdt_attrs))
122                         RETURN(-EINVAL);
123
124                 fl = LU_XATTR_REPLACE;
125                 lustre_lma_swab(lma);
126                 lustre_lma_init(lma, lfsck_dto2fid(obj),
127                                 lma->lma_compat | LMAC_FID_ON_OST,
128                                 lma->lma_incompat);
129         }
130         lustre_lma_swab(lma);
131
132         th = dt_trans_create(env, dt);
133         if (IS_ERR(th))
134                 RETURN(PTR_ERR(th));
135
136         buf = lfsck_buf_get(env, lma, sizeof(*lma));
137         rc = dt_declare_xattr_set(env, obj, buf, XATTR_NAME_LMA, fl, th);
138         if (rc != 0)
139                 GOTO(stop, rc);
140
141         rc = dt_trans_start(env, dt, th);
142         if (rc != 0)
143                 GOTO(stop, rc);
144
145         rc = dt_xattr_set(env, obj, buf, XATTR_NAME_LMA, fl, th, BYPASS_CAPA);
146
147         GOTO(stop, rc);
148
149 stop:
150         dt_trans_stop(env, dt, th);
151         return rc;
152 }
153
154 static int lfsck_parent_fid(const struct lu_env *env, struct dt_object *obj,
155                             struct lu_fid *fid)
156 {
157         if (unlikely(!S_ISDIR(lfsck_object_type(obj)) ||
158                      !dt_try_as_dir(env, obj)))
159                 return -ENOTDIR;
160
161         return dt_lookup(env, obj, (struct dt_rec *)fid,
162                          (const struct dt_key *)"..", BYPASS_CAPA);
163 }
164
165 /**
166  * Check whether needs to scan the directory or not.
167  *
168  * 1) If we are not doing namespace LFSCK, or the given @obj is not directory,
169  *    then needs not to scan the @obj. Otherwise,
170  * 2) Global /ROOT needs to be scanned, backend root needs not to be scanned.
171  * 3) If the @obj is neither IGIF nor normal FID (including .lustre and its
172  *    sub-directories that have been scanned when the LFSCK engine start),
173  *    then needs not to be scanned.
174  * 4) If it is a remote object, then scanning the object will be done on the
175  *    MDT on which the object really resides.
176  * 5) If the local object has normal FID, then needs to be scanned. Otherwise,
177  * 6) If the object has linkEA, then needs to be scanned. Otherwise,
178  * 7) If none of the previous conditions are true, we need to check the parent
179  *    directories whether this subdirectory is in a tree that should be scanned.
180  *    Set the parent as current @obj, repeat 2)-7).
181  *
182  * \param[in] env       pointer to the thread context
183  * \param[in] lfsck     pointer to the lfsck instance
184  * \param[in] obj       pointer to the object to be checked
185  *
186  * \retval              positive number if the directory needs to be scanned
187  * \retval              0 if the directory needs NOT to be scanned
188  * \retval              negative error number on failure
189  */
190 static int lfsck_needs_scan_dir(const struct lu_env *env,
191                                 struct lfsck_instance *lfsck,
192                                 struct dt_object *obj)
193 {
194         struct lfsck_thread_info *info    = lfsck_env_info(env);
195         struct lu_fid            *fid     = &info->lti_fid;
196         struct lu_seq_range      *range   = &info->lti_range;
197         struct dt_device         *dev     = lfsck->li_bottom;
198         struct seq_server_site   *ss      = lu_site2seq(dev->dd_lu_dev.ld_site);
199         __u32                     idx     = lfsck_dev_idx(dev);
200         int                       depth   = 0;
201         int                       rc      = 0;
202
203         if (list_empty(&lfsck->li_list_dir) || !S_ISDIR(lfsck_object_type(obj)))
204                 return 0;
205
206         LASSERT(ss != NULL);
207
208         *fid = *lfsck_dto2fid(obj);
209         while (1) {
210                 /* Global /ROOT is visible. */
211                 if (unlikely(lu_fid_eq(fid, &lfsck->li_global_root_fid)))
212                         return 1;
213
214                 /* Backend root is invisible. */
215                 if (unlikely(lu_fid_eq(fid, &lfsck->li_local_root_fid)))
216                         return 0;
217
218                 if (!fid_is_norm(fid) && !fid_is_igif(fid))
219                         return 0;
220
221                 fld_range_set_mdt(range);
222                 rc = fld_local_lookup(env, ss->ss_server_fld,
223                                       fid_seq(fid), range);
224                 if (rc != 0 || range->lsr_index != idx) {
225                         /* Current FID should NOT be for the input parameter
226                          * @obj, because the lfsck_master_oit_engine() has
227                          * filtered out agent object. So current FID is for
228                          * the ancestor of the original input parameter @obj.
229                          * So the ancestor is a remote directory. The input
230                          * parameter @obj is local directory, and should be
231                          * scanned under such case. */
232                         LASSERT(depth > 0);
233
234                         return 1;
235                 }
236
237                 /* normal FID on this target (locally) must be for the
238                  * client-side visiable object. */
239                 if (fid_is_norm(fid))
240                         return 1;
241
242                 if (obj == NULL) {
243                         obj = lfsck_object_find(env, lfsck, fid);
244                         if (IS_ERR(obj))
245                                 return PTR_ERR(obj);
246
247                         depth++;
248                         if (!dt_object_exists(obj))
249                                 GOTO(out, rc = 0);
250                 }
251
252                 dt_read_lock(env, obj, MOR_TGT_CHILD);
253                 if (unlikely(lfsck_is_dead_obj(obj))) {
254                         dt_read_unlock(env, obj);
255
256                         GOTO(out, rc = 0);
257                 }
258
259                 rc = dt_xattr_get(env, obj,
260                                   lfsck_buf_get(env, NULL, 0), XATTR_NAME_LINK,
261                                   BYPASS_CAPA);
262                 dt_read_unlock(env, obj);
263                 if (rc >= 0)
264                         GOTO(out, rc = 1);
265
266                 if (rc < 0 && rc != -ENODATA)
267                         GOTO(out, rc);
268
269                 rc = lfsck_parent_fid(env, obj, fid);
270                 if (depth > 0)
271                         lfsck_object_put(env, obj);
272
273                 obj = NULL;
274                 if (rc != 0)
275                         return rc;
276
277                 if (!fid_is_sane(fid))
278                         return 0;
279         }
280
281 out:
282         if (depth > 0 && obj != NULL)
283                 lfsck_object_put(env, obj);
284
285         return rc;
286 }
287
288 static int lfsck_load_stripe_lmv(const struct lu_env *env,
289                                  struct lfsck_instance *lfsck,
290                                  struct dt_object *obj)
291 {
292         struct lmv_mds_md_v1    *lmv    = &lfsck_env_info(env)->lti_lmv;
293         struct lfsck_lmv        *llmv;
294         int                      rc;
295         ENTRY;
296
297         LASSERT(lfsck->li_obj_dir == NULL);
298         LASSERT(lfsck->li_lmv == NULL);
299
300         rc = lfsck_read_stripe_lmv(env, obj, lmv);
301         if (rc == -ENODATA) {
302                 lfsck->li_obj_dir = lfsck_object_get(obj);
303
304                 RETURN(0);
305         }
306
307         if (rc < 0)
308                 RETURN(rc);
309
310         OBD_ALLOC_PTR(llmv);
311         if (llmv == NULL)
312                 RETURN(-ENOMEM);
313
314         if (lmv->lmv_magic == LMV_MAGIC) {
315                 struct lfsck_slave_lmv_rec      *lslr;
316                 __u32                            stripes;
317
318                 llmv->ll_lmv_master = 1;
319                 if (lmv->lmv_stripe_count < 1)
320                         stripes = LFSCK_LMV_DEF_STRIPES;
321                 else if (lmv->lmv_stripe_count > LFSCK_LMV_MAX_STRIPES)
322                         stripes = LFSCK_LMV_MAX_STRIPES;
323                 else
324                         stripes = lmv->lmv_stripe_count;
325
326                 OBD_ALLOC_LARGE(lslr, sizeof(*lslr) * stripes);
327                 if (lslr == NULL) {
328                         OBD_FREE_PTR(llmv);
329
330                         RETURN(-ENOMEM);
331                 }
332
333                 /* Find the object against the bottom device. */
334                 obj = lfsck_object_find_by_dev(env, lfsck->li_bottom,
335                                                lfsck_dto2fid(obj));
336                 if (IS_ERR(obj)) {
337                         OBD_FREE_LARGE(lslr, sizeof(*lslr) * stripes);
338                         OBD_FREE_PTR(llmv);
339
340                         RETURN(PTR_ERR(obj));
341                 }
342
343                 llmv->ll_stripes_allocated = stripes;
344                 llmv->ll_hash_type = LMV_HASH_TYPE_UNKNOWN;
345                 llmv->ll_lslr = lslr;
346                 lfsck->li_obj_dir = obj;
347         } else {
348                 llmv->ll_lmv_slave = 1;
349                 lfsck->li_obj_dir = lfsck_object_get(obj);
350         }
351
352         llmv->ll_lmv = *lmv;
353         atomic_set(&llmv->ll_ref, 1);
354         lfsck->li_lmv = llmv;
355
356         RETURN(0);
357 }
358
359 /* LFSCK wrap functions */
360
361 static void lfsck_fail(const struct lu_env *env, struct lfsck_instance *lfsck,
362                        bool new_checked)
363 {
364         struct lfsck_component *com;
365
366         list_for_each_entry(com, &lfsck->li_list_scan, lc_link) {
367                 com->lc_ops->lfsck_fail(env, com, new_checked);
368         }
369 }
370
371 void lfsck_close_dir(const struct lu_env *env,
372                      struct lfsck_instance *lfsck, int result)
373 {
374         struct lfsck_component *com;
375         ENTRY;
376
377         if (lfsck->li_lmv != NULL) {
378                 lfsck->li_lmv->ll_exit_value = result;
379                 if (lfsck->li_obj_dir != NULL) {
380                         list_for_each_entry(com, &lfsck->li_list_dir,
381                                             lc_link_dir) {
382                                 com->lc_ops->lfsck_close_dir(env, com);
383                         }
384                 }
385
386                 lfsck_lmv_put(env, lfsck->li_lmv);
387                 lfsck->li_lmv = NULL;
388         }
389
390         if (lfsck->li_di_dir != NULL) {
391                 const struct dt_it_ops  *dir_iops =
392                                 &lfsck->li_obj_dir->do_index_ops->dio_it;
393                 struct dt_it            *dir_di   = lfsck->li_di_dir;
394
395                 lfsck_di_dir_put(env, lfsck);
396                 dir_iops->fini(env, dir_di);
397         }
398
399         if (lfsck->li_obj_dir != NULL) {
400                 struct dt_object        *dir_obj  = lfsck->li_obj_dir;
401
402                 lfsck->li_obj_dir = NULL;
403                 lfsck_object_put(env, dir_obj);
404         }
405
406         EXIT;
407 }
408
409 int lfsck_open_dir(const struct lu_env *env,
410                    struct lfsck_instance *lfsck, __u64 cookie)
411 {
412         struct dt_object        *obj    = lfsck->li_obj_dir;
413         struct dt_it            *di     = lfsck->li_di_dir;
414         struct lfsck_component  *com;
415         const struct dt_it_ops  *iops;
416         int                      rc     = 0;
417         ENTRY;
418
419         LASSERT(obj != NULL);
420         LASSERT(di == NULL);
421
422         if (unlikely(!dt_try_as_dir(env, obj)))
423                 GOTO(out, rc = -ENOTDIR);
424
425         list_for_each_entry(com, &lfsck->li_list_dir, lc_link_dir) {
426                 rc = com->lc_ops->lfsck_open_dir(env, com);
427                 if (rc != 0)
428                         GOTO(out, rc);
429         }
430
431         iops = &obj->do_index_ops->dio_it;
432         di = iops->init(env, obj, lfsck->li_args_dir, BYPASS_CAPA);
433         if (IS_ERR(di))
434                 GOTO(out, rc = PTR_ERR(di));
435
436         rc = iops->load(env, di, cookie);
437         if (rc == 0 || (rc > 0 && cookie > 0))
438                 rc = iops->next(env, di);
439         else if (rc > 0)
440                 rc = 0;
441
442         if (rc != 0) {
443                 iops->put(env, di);
444                 iops->fini(env, di);
445         } else {
446                 lfsck->li_cookie_dir = iops->store(env, di);
447                 spin_lock(&lfsck->li_lock);
448                 lfsck->li_di_dir = di;
449                 spin_unlock(&lfsck->li_lock);
450         }
451
452         GOTO(out, rc);
453
454 out:
455         if (rc != 0)
456                 lfsck_close_dir(env, lfsck, rc);
457
458         return rc;
459 }
460
461 static int lfsck_checkpoint(const struct lu_env *env,
462                             struct lfsck_instance *lfsck)
463 {
464         struct lfsck_component *com;
465         int                     rc  = 0;
466         int                     rc1 = 0;
467
468         if (likely(cfs_time_beforeq(cfs_time_current(),
469                                     lfsck->li_time_next_checkpoint)))
470                 return 0;
471
472         lfsck_pos_fill(env, lfsck, &lfsck->li_pos_checkpoint, false);
473         list_for_each_entry(com, &lfsck->li_list_scan, lc_link) {
474                 rc = com->lc_ops->lfsck_checkpoint(env, com, false);
475                 if (rc != 0)
476                         rc1 = rc;
477         }
478
479         lfsck->li_time_last_checkpoint = cfs_time_current();
480         lfsck->li_time_next_checkpoint = lfsck->li_time_last_checkpoint +
481                                 cfs_time_seconds(LFSCK_CHECKPOINT_INTERVAL);
482         return rc1 != 0 ? rc1 : rc;
483 }
484
485 static int lfsck_prep(const struct lu_env *env, struct lfsck_instance *lfsck,
486                       struct lfsck_start_param *lsp)
487 {
488         struct dt_object       *obj     = NULL;
489         struct lfsck_component *com;
490         struct lfsck_component *next;
491         struct lfsck_position  *pos     = NULL;
492         const struct dt_it_ops *iops    =
493                                 &lfsck->li_obj_oit->do_index_ops->dio_it;
494         int                     rc;
495         ENTRY;
496
497         LASSERT(lfsck->li_obj_dir == NULL);
498         LASSERT(lfsck->li_di_dir == NULL);
499
500         lfsck->li_current_oit_processed = 0;
501         list_for_each_entry_safe(com, next, &lfsck->li_list_scan, lc_link) {
502                 com->lc_new_checked = 0;
503                 rc = com->lc_ops->lfsck_prep(env, com, lsp);
504                 if (rc != 0)
505                         GOTO(out, rc);
506
507                 if ((pos == NULL) ||
508                     (!lfsck_pos_is_zero(&com->lc_pos_start) &&
509                      lfsck_pos_is_eq(pos, &com->lc_pos_start) > 0))
510                         pos = &com->lc_pos_start;
511         }
512
513         /* Init otable-based iterator. */
514         if (pos == NULL) {
515                 rc = iops->load(env, lfsck->li_di_oit, 0);
516                 if (rc > 0) {
517                         lfsck->li_oit_over = 1;
518                         rc = 0;
519                 }
520
521                 GOTO(out, rc);
522         }
523
524         rc = iops->load(env, lfsck->li_di_oit, pos->lp_oit_cookie);
525         if (rc < 0)
526                 GOTO(out, rc);
527         else if (rc > 0)
528                 lfsck->li_oit_over = 1;
529
530         if (!lfsck->li_master || fid_is_zero(&pos->lp_dir_parent))
531                 GOTO(out, rc = 0);
532
533         /* Find the directory for namespace-based traverse. */
534         obj = lfsck_object_find(env, lfsck, &pos->lp_dir_parent);
535         if (IS_ERR(obj))
536                 RETURN(PTR_ERR(obj));
537
538         /* Remote directory will be scanned by the LFSCK instance
539          * on the MDT where the remote object really resides on. */
540         if (!dt_object_exists(obj) || dt_object_remote(obj) ||
541             unlikely(!S_ISDIR(lfsck_object_type(obj))))
542                 GOTO(out, rc = 0);
543
544         rc = lfsck_load_stripe_lmv(env, lfsck, obj);
545         if (rc == 0) {
546                 /* For the master MDT-object of a striped directory,
547                  * reset the iteration from the directory beginning. */
548                 if (lfsck->li_lmv != NULL && lfsck->li_lmv->ll_lmv_master)
549                         pos->lp_dir_cookie = 0;
550
551                 rc = lfsck_open_dir(env, lfsck, pos->lp_dir_cookie);
552         }
553
554         GOTO(out, rc);
555
556 out:
557         if (obj != NULL)
558                 lfsck_object_put(env, obj);
559
560         if (rc != 0) {
561                 lfsck_close_dir(env, lfsck, rc);
562                 list_for_each_entry_safe(com, next, &lfsck->li_list_scan,
563                                          lc_link) {
564                         com->lc_ops->lfsck_post(env, com, rc, true);
565                 }
566
567                 return rc;
568         }
569
570         rc = 0;
571         lfsck_pos_fill(env, lfsck, &lfsck->li_pos_checkpoint, true);
572         lfsck->li_pos_current = lfsck->li_pos_checkpoint;
573         list_for_each_entry(com, &lfsck->li_list_scan, lc_link) {
574                 rc = com->lc_ops->lfsck_checkpoint(env, com, true);
575                 if (rc != 0)
576                         break;
577         }
578
579         lfsck->li_time_last_checkpoint = cfs_time_current();
580         lfsck->li_time_next_checkpoint = lfsck->li_time_last_checkpoint +
581                                 cfs_time_seconds(LFSCK_CHECKPOINT_INTERVAL);
582         return rc;
583 }
584
585 static int lfsck_exec_oit(const struct lu_env *env,
586                           struct lfsck_instance *lfsck, struct dt_object *obj)
587 {
588         struct lfsck_component *com;
589         int                     rc;
590         ENTRY;
591
592         LASSERT(lfsck->li_obj_dir == NULL);
593
594         list_for_each_entry(com, &lfsck->li_list_scan, lc_link) {
595                 rc = com->lc_ops->lfsck_exec_oit(env, com, obj);
596                 if (rc != 0)
597                         RETURN(rc);
598         }
599
600         rc = lfsck_needs_scan_dir(env, lfsck, obj);
601         if (rc <= 0)
602                 GOTO(out, rc);
603
604         rc = lfsck_load_stripe_lmv(env, lfsck, obj);
605         if (rc == 0)
606                 rc = lfsck_open_dir(env, lfsck, 0);
607
608         GOTO(out, rc);
609
610 out:
611         if (rc < 0)
612                 lfsck_fail(env, lfsck, false);
613
614         if (rc != 0)
615                 lfsck_close_dir(env, lfsck, rc);
616
617         return rc > 0 ? 0 : rc;
618 }
619
620 static int lfsck_exec_dir(const struct lu_env *env,
621                           struct lfsck_instance *lfsck,
622                           struct lu_dirent *ent, __u16 type)
623 {
624         struct lfsck_component *com;
625         int                     rc;
626
627         list_for_each_entry(com, &lfsck->li_list_scan, lc_link) {
628                 rc = com->lc_ops->lfsck_exec_dir(env, com, ent, type);
629                 if (rc != 0)
630                         return rc;
631         }
632         return 0;
633 }
634
635 static int lfsck_master_dir_engine(const struct lu_env *env,
636                                    struct lfsck_instance *lfsck);
637
638 static int lfsck_post(const struct lu_env *env, struct lfsck_instance *lfsck,
639                       int result)
640 {
641         struct lfsck_component *com;
642         struct lfsck_component *next;
643         int                     rc  = result;
644
645         lfsck_pos_fill(env, lfsck, &lfsck->li_pos_checkpoint, false);
646         lfsck_close_dir(env, lfsck, result);
647
648         while (thread_is_running(&lfsck->li_thread) && rc > 0 &&
649                !list_empty(&lfsck->li_list_lmv)) {
650                 struct lfsck_lmv_unit *llu;
651
652                 spin_lock(&lfsck->li_lock);
653                 llu = list_entry(lfsck->li_list_lmv.next,
654                                  struct lfsck_lmv_unit, llu_link);
655                 list_del_init(&llu->llu_link);
656                 spin_unlock(&lfsck->li_lock);
657
658                 lfsck->li_lmv = &llu->llu_lmv;
659                 lfsck->li_obj_dir = lfsck_object_get(llu->llu_obj);
660                 rc = lfsck_open_dir(env, lfsck, 0);
661                 if (rc == 0) {
662                         rc = lfsck_master_dir_engine(env, lfsck);
663                         lfsck_close_dir(env, lfsck, result);
664                 }
665         }
666
667         result = rc;
668
669         list_for_each_entry_safe(com, next, &lfsck->li_list_scan, lc_link) {
670                 rc = com->lc_ops->lfsck_post(env, com, result, false);
671                 if (rc != 0)
672                         CDEBUG(D_LFSCK, "%s: lfsck_post at the component %u: "
673                                "rc = %d\n", lfsck_lfsck2name(lfsck),
674                                (__u32)com->lc_type, rc);
675         }
676
677         lfsck->li_time_last_checkpoint = cfs_time_current();
678         lfsck->li_time_next_checkpoint = lfsck->li_time_last_checkpoint +
679                                 cfs_time_seconds(LFSCK_CHECKPOINT_INTERVAL);
680
681         /* Ignore some component post failure to make other can go ahead. */
682         return result;
683 }
684
685 static int lfsck_double_scan(const struct lu_env *env,
686                              struct lfsck_instance *lfsck)
687 {
688         struct lfsck_component *com;
689         struct lfsck_component *next;
690         struct l_wait_info      lwi = { 0 };
691         int                     rc  = 0;
692         int                     rc1 = 0;
693
694         list_for_each_entry(com, &lfsck->li_list_double_scan, lc_link) {
695                 rc = com->lc_ops->lfsck_double_scan(env, com);
696                 if (rc != 0)
697                         rc1 = rc;
698         }
699
700         l_wait_event(lfsck->li_thread.t_ctl_waitq,
701                      atomic_read(&lfsck->li_double_scan_count) == 0,
702                      &lwi);
703
704         if (lfsck->li_status != LS_PAUSED &&
705             lfsck->li_status != LS_CO_PAUSED) {
706                 list_for_each_entry_safe(com, next, &lfsck->li_list_double_scan,
707                                          lc_link) {
708                         spin_lock(&lfsck->li_lock);
709                         list_move_tail(&com->lc_link, &lfsck->li_list_idle);
710                         spin_unlock(&lfsck->li_lock);
711                 }
712         }
713
714         return rc1 != 0 ? rc1 : rc;
715 }
716
717 static void lfsck_quit(const struct lu_env *env, struct lfsck_instance *lfsck)
718 {
719         struct lfsck_component *com;
720         struct lfsck_component *next;
721
722         list_for_each_entry_safe(com, next, &lfsck->li_list_scan,
723                                  lc_link) {
724                 if (com->lc_ops->lfsck_quit != NULL)
725                         com->lc_ops->lfsck_quit(env, com);
726
727                 spin_lock(&lfsck->li_lock);
728                 list_del_init(&com->lc_link_dir);
729                 list_move_tail(&com->lc_link, &lfsck->li_list_idle);
730                 spin_unlock(&lfsck->li_lock);
731         }
732
733         list_for_each_entry_safe(com, next, &lfsck->li_list_double_scan,
734                                  lc_link) {
735                 if (com->lc_ops->lfsck_quit != NULL)
736                         com->lc_ops->lfsck_quit(env, com);
737
738                 spin_lock(&lfsck->li_lock);
739                 list_move_tail(&com->lc_link, &lfsck->li_list_idle);
740                 spin_unlock(&lfsck->li_lock);
741         }
742 }
743
744 /* LFSCK engines */
745
746 static int lfsck_master_dir_engine(const struct lu_env *env,
747                                    struct lfsck_instance *lfsck)
748 {
749         struct lfsck_thread_info        *info   = lfsck_env_info(env);
750         struct dt_object                *dir    = lfsck->li_obj_dir;
751         const struct dt_it_ops          *iops   = &dir->do_index_ops->dio_it;
752         struct dt_it                    *di     = lfsck->li_di_dir;
753         struct lu_dirent                *ent    =
754                         (struct lu_dirent *)info->lti_key;
755         struct lfsck_bookmark           *bk     = &lfsck->li_bookmark_ram;
756         struct ptlrpc_thread            *thread = &lfsck->li_thread;
757         int                              rc;
758         __u16                            type;
759         ENTRY;
760
761         do {
762                 if (OBD_FAIL_CHECK(OBD_FAIL_LFSCK_DELAY2) &&
763                     cfs_fail_val > 0) {
764                         struct l_wait_info lwi;
765
766                         lwi = LWI_TIMEOUT(cfs_time_seconds(cfs_fail_val),
767                                           NULL, NULL);
768                         l_wait_event(thread->t_ctl_waitq,
769                                      !thread_is_running(thread),
770                                      &lwi);
771
772                         if (unlikely(!thread_is_running(thread))) {
773                                 CDEBUG(D_LFSCK, "%s: scan dir exit for engine "
774                                        "stop, parent "DFID", cookie "LPX64"\n",
775                                        lfsck_lfsck2name(lfsck),
776                                        PFID(lfsck_dto2fid(dir)),
777                                        lfsck->li_cookie_dir);
778                                 RETURN(0);
779                         }
780                 }
781
782                 lfsck->li_new_scanned++;
783                 rc = iops->rec(env, di, (struct dt_rec *)ent,
784                                lfsck->li_args_dir);
785                 if (rc == 0)
786                         rc = lfsck_unpack_ent(ent, &lfsck->li_cookie_dir,
787                                               &type);
788
789                 if (rc != 0) {
790                         CDEBUG(D_LFSCK, "%s: scan dir failed at rec(), "
791                                "parent "DFID", cookie "LPX64": rc = %d\n",
792                                lfsck_lfsck2name(lfsck),
793                                PFID(lfsck_dto2fid(dir)),
794                                lfsck->li_cookie_dir, rc);
795                         lfsck_fail(env, lfsck, true);
796                         if (bk->lb_param & LPF_FAILOUT)
797                                 RETURN(rc);
798                         else
799                                 goto checkpoint;
800                 }
801
802                 if (ent->lde_attrs & LUDA_IGNORE &&
803                     strcmp(ent->lde_name, dotdot) != 0)
804                         goto checkpoint;
805
806                 /* The type in the @ent structure may has been overwritten,
807                  * so we need to pass the @type parameter independently. */
808                 rc = lfsck_exec_dir(env, lfsck, ent, type);
809                 if (rc != 0 && bk->lb_param & LPF_FAILOUT)
810                         RETURN(rc);
811
812 checkpoint:
813                 rc = lfsck_checkpoint(env, lfsck);
814                 if (rc != 0 && bk->lb_param & LPF_FAILOUT)
815                         RETURN(rc);
816
817                 /* Rate control. */
818                 lfsck_control_speed(lfsck);
819                 if (unlikely(!thread_is_running(thread))) {
820                         CDEBUG(D_LFSCK, "%s: scan dir exit for engine stop, "
821                                "parent "DFID", cookie "LPX64"\n",
822                                lfsck_lfsck2name(lfsck),
823                                PFID(lfsck_dto2fid(dir)),
824                                lfsck->li_cookie_dir);
825                         RETURN(0);
826                 }
827
828                 if (OBD_FAIL_CHECK(OBD_FAIL_LFSCK_FATAL2)) {
829                         spin_lock(&lfsck->li_lock);
830                         thread_set_flags(thread, SVC_STOPPING);
831                         spin_unlock(&lfsck->li_lock);
832                         RETURN(-EINVAL);
833                 }
834
835                 rc = iops->next(env, di);
836         } while (rc == 0);
837
838         if (rc > 0 && !lfsck->li_oit_over)
839                 lfsck_close_dir(env, lfsck, rc);
840
841         RETURN(rc);
842 }
843
844 /**
845  * Object-table based iteration engine.
846  *
847  * Object-table based iteration is the basic linear engine to scan all the
848  * objects on current device in turn. For each object, it calls all the
849  * registered LFSCK component(s)' API to perform related consistency
850  * verification.
851  *
852  * It flushes related LFSCK trace files to disk via making checkpoint
853  * periodically. Then if the server crashed or the LFSCK is paused, the
854  * LFSCK can resume from the latest checkpoint.
855  *
856  * It also controls the whole LFSCK speed via lfsck_control_speed() to
857  * avoid the server to become overload.
858  *
859  * \param[in] env       pointer to the thread context
860  * \param[in] lfsck     pointer to the lfsck instance
861  *
862  * \retval              positive number if all objects have been scanned
863  * \retval              0 if the iteration is stopped or paused
864  * \retval              negative error number on failure
865  */
866 static int lfsck_master_oit_engine(const struct lu_env *env,
867                                    struct lfsck_instance *lfsck)
868 {
869         struct lfsck_thread_info *info  = lfsck_env_info(env);
870         const struct dt_it_ops   *iops  =
871                                 &lfsck->li_obj_oit->do_index_ops->dio_it;
872         struct dt_it             *di    = lfsck->li_di_oit;
873         struct lu_fid            *fid   = &info->lti_fid;
874         struct lfsck_bookmark    *bk    = &lfsck->li_bookmark_ram;
875         struct ptlrpc_thread     *thread = &lfsck->li_thread;
876         struct dt_device         *dev   = lfsck->li_bottom;
877         struct seq_server_site   *ss    = lu_site2seq(dev->dd_lu_dev.ld_site);
878         __u32                    idx    = lfsck_dev_idx(dev);
879         int                      rc;
880         ENTRY;
881
882         if (unlikely(ss == NULL))
883                 RETURN(-EIO);
884
885         do {
886                 struct dt_object *target;
887                 bool              update_lma = false;
888
889                 if (lfsck->li_di_dir != NULL) {
890                         rc = lfsck_master_dir_engine(env, lfsck);
891                         if (rc <= 0)
892                                 RETURN(rc);
893                 }
894
895                 if (unlikely(lfsck->li_oit_over))
896                         RETURN(1);
897
898                 if (OBD_FAIL_CHECK(OBD_FAIL_LFSCK_DELAY1) &&
899                     cfs_fail_val > 0) {
900                         struct l_wait_info lwi;
901
902                         lwi = LWI_TIMEOUT(cfs_time_seconds(cfs_fail_val),
903                                           NULL, NULL);
904                         l_wait_event(thread->t_ctl_waitq,
905                                      !thread_is_running(thread),
906                                      &lwi);
907
908                         if (unlikely(!thread_is_running(thread))) {
909                                 CDEBUG(D_LFSCK, "%s: OIT scan exit for engine "
910                                        "stop, cookie "LPU64"\n",
911                                        lfsck_lfsck2name(lfsck),
912                                        iops->store(env, di));
913                                 RETURN(0);
914                         }
915                 }
916
917                 if (OBD_FAIL_CHECK(OBD_FAIL_LFSCK_CRASH))
918                         RETURN(0);
919
920                 lfsck->li_current_oit_processed = 1;
921
922                 if (!list_empty(&lfsck->li_list_lmv)) {
923                         struct lfsck_lmv_unit *llu;
924
925                         spin_lock(&lfsck->li_lock);
926                         llu = list_entry(lfsck->li_list_lmv.next,
927                                          struct lfsck_lmv_unit, llu_link);
928                         list_del_init(&llu->llu_link);
929                         spin_unlock(&lfsck->li_lock);
930
931                         lfsck->li_lmv = &llu->llu_lmv;
932                         lfsck->li_obj_dir = lfsck_object_get(llu->llu_obj);
933                         rc = lfsck_open_dir(env, lfsck, 0);
934                         if (rc == 0)
935                                 rc = lfsck_master_dir_engine(env, lfsck);
936
937                         if (rc <= 0)
938                                 RETURN(rc);
939                 }
940
941                 lfsck->li_new_scanned++;
942                 lfsck->li_pos_current.lp_oit_cookie = iops->store(env, di);
943                 rc = iops->rec(env, di, (struct dt_rec *)fid, 0);
944                 if (rc != 0) {
945                         CDEBUG(D_LFSCK, "%s: OIT scan failed at rec(): "
946                                "rc = %d\n", lfsck_lfsck2name(lfsck), rc);
947                         lfsck_fail(env, lfsck, true);
948                         if (rc < 0 && bk->lb_param & LPF_FAILOUT)
949                                 RETURN(rc);
950                         else
951                                 goto checkpoint;
952                 }
953
954                 if (fid_is_idif(fid)) {
955                         __u32 idx1 = fid_idif_ost_idx(fid);
956
957                         LASSERT(!lfsck->li_master);
958
959                         /* It is an old format device, update the LMA. */
960                         if (idx != idx1) {
961                                 struct ost_id *oi = &info->lti_oi;
962
963                                 fid_to_ostid(fid, oi);
964                                 ostid_to_fid(fid, oi, idx);
965                                 update_lma = true;
966                         }
967                 } else if (!fid_is_norm(fid) && !fid_is_igif(fid) &&
968                            !fid_is_last_id(fid) &&
969                            !lu_fid_eq(fid, &lfsck->li_global_root_fid)) {
970
971                         /* If the FID/object is only used locally and invisible
972                          * to external nodes, then LFSCK will not handle it.
973                          *
974                          * dot_lustre sequence has been handled specially. */
975                         goto checkpoint;
976                 } else {
977                         struct lu_seq_range *range = &info->lti_range;
978
979                         if (lfsck->li_master)
980                                 fld_range_set_mdt(range);
981                         else
982                                 fld_range_set_ost(range);
983                         rc = fld_local_lookup(env, ss->ss_server_fld,
984                                               fid_seq(fid), range);
985                         if (rc != 0 || range->lsr_index != idx) {
986                                 /* Remote object will be handled by the LFSCK
987                                  * instance on the MDT where the remote object
988                                  * really resides on. */
989                                 rc = 0;
990                                 goto checkpoint;
991                         }
992                 }
993
994                 target = lfsck_object_find(env, lfsck, fid);
995                 if (IS_ERR(target)) {
996                         CDEBUG(D_LFSCK, "%s: OIT scan failed at find target "
997                                DFID", cookie "LPU64": rc = %d\n",
998                                lfsck_lfsck2name(lfsck), PFID(fid),
999                                iops->store(env, di), rc);
1000                         lfsck_fail(env, lfsck, true);
1001                         if (bk->lb_param & LPF_FAILOUT)
1002                                 RETURN(PTR_ERR(target));
1003                         else
1004                                 goto checkpoint;
1005                 }
1006
1007                 if (dt_object_exists(target)) {
1008                         if (update_lma) {
1009                                 rc = lfsck_update_lma(env, lfsck, target);
1010                                 if (rc != 0)
1011                                         CDEBUG(D_LFSCK, "%s: fail to update "
1012                                                "LMA for "DFID": rc = %d\n",
1013                                                lfsck_lfsck2name(lfsck),
1014                                                PFID(lfsck_dto2fid(target)), rc);
1015                         }
1016                         if (rc == 0)
1017                                 rc = lfsck_exec_oit(env, lfsck, target);
1018                 }
1019                 lfsck_object_put(env, target);
1020                 if (rc != 0 && bk->lb_param & LPF_FAILOUT)
1021                         RETURN(rc);
1022
1023 checkpoint:
1024                 rc = lfsck_checkpoint(env, lfsck);
1025                 if (rc != 0 && bk->lb_param & LPF_FAILOUT)
1026                         RETURN(rc);
1027
1028                 /* Rate control. */
1029                 lfsck_control_speed(lfsck);
1030
1031                 if (OBD_FAIL_CHECK(OBD_FAIL_LFSCK_FATAL1)) {
1032                         spin_lock(&lfsck->li_lock);
1033                         thread_set_flags(thread, SVC_STOPPING);
1034                         spin_unlock(&lfsck->li_lock);
1035                         RETURN(-EINVAL);
1036                 }
1037
1038                 rc = iops->next(env, di);
1039                 if (unlikely(rc > 0))
1040                         lfsck->li_oit_over = 1;
1041                 else if (likely(rc == 0))
1042                         lfsck->li_current_oit_processed = 0;
1043
1044                 if (unlikely(!thread_is_running(thread))) {
1045                         CDEBUG(D_LFSCK, "%s: OIT scan exit for engine stop, "
1046                                "cookie "LPU64"\n", lfsck_lfsck2name(lfsck),
1047                                iops->store(env, di));
1048                         RETURN(0);
1049                 }
1050         } while (rc == 0 || lfsck->li_di_dir != NULL);
1051
1052         RETURN(rc);
1053 }
1054
1055 int lfsck_master_engine(void *args)
1056 {
1057         struct lfsck_thread_args *lta      = args;
1058         struct lu_env            *env      = &lta->lta_env;
1059         struct lfsck_instance    *lfsck    = lta->lta_lfsck;
1060         struct ptlrpc_thread     *thread   = &lfsck->li_thread;
1061         struct dt_object         *oit_obj  = lfsck->li_obj_oit;
1062         const struct dt_it_ops   *oit_iops = &oit_obj->do_index_ops->dio_it;
1063         struct dt_it             *oit_di;
1064         struct l_wait_info        lwi      = { 0 };
1065         int                       rc;
1066         ENTRY;
1067
1068         if (lfsck->li_master &&
1069             (!list_empty(&lfsck->li_list_scan) ||
1070              !list_empty(&lfsck->li_list_double_scan))) {
1071                 rc = lfsck_verify_lpf(env, lfsck);
1072                 /* Fail to verify the .lustre/lost+found/MDTxxxx/ may be not
1073                  * fatal, because the .lustre/lost+found/ maybe not accessed
1074                  * by the LFSCK if it does not add orphans or others to such
1075                  * directory. So go ahead until hit failure when really uses
1076                  * the directory. */
1077                 if (rc != 0)
1078                         CDEBUG(D_LFSCK, "%s: master engine fail to verify the "
1079                                ".lustre/lost+found/, go ahead: rc = %d\n",
1080                                lfsck_lfsck2name(lfsck), rc);
1081         }
1082
1083         oit_di = oit_iops->init(env, oit_obj, lfsck->li_args_oit, BYPASS_CAPA);
1084         if (IS_ERR(oit_di)) {
1085                 rc = PTR_ERR(oit_di);
1086                 CDEBUG(D_LFSCK, "%s: master engine fail to init iteration: "
1087                        "rc = %d\n", lfsck_lfsck2name(lfsck), rc);
1088
1089                 GOTO(fini_args, rc);
1090         }
1091
1092         spin_lock(&lfsck->li_lock);
1093         lfsck->li_di_oit = oit_di;
1094         spin_unlock(&lfsck->li_lock);
1095         rc = lfsck_prep(env, lfsck, lta->lta_lsp);
1096         if (rc != 0)
1097                 GOTO(fini_oit, rc);
1098
1099         CDEBUG(D_LFSCK, "LFSCK entry: oit_flags = %#x, dir_flags = %#x, "
1100                "oit_cookie = "LPU64", dir_cookie = "LPX64", parent = "DFID
1101                ", pid = %d\n", lfsck->li_args_oit, lfsck->li_args_dir,
1102                lfsck->li_pos_checkpoint.lp_oit_cookie,
1103                lfsck->li_pos_checkpoint.lp_dir_cookie,
1104                PFID(&lfsck->li_pos_checkpoint.lp_dir_parent),
1105                current_pid());
1106
1107         spin_lock(&lfsck->li_lock);
1108         thread_set_flags(thread, SVC_RUNNING);
1109         spin_unlock(&lfsck->li_lock);
1110         wake_up_all(&thread->t_ctl_waitq);
1111
1112         l_wait_event(thread->t_ctl_waitq,
1113                      lfsck->li_start_unplug ||
1114                      !thread_is_running(thread),
1115                      &lwi);
1116         if (!thread_is_running(thread))
1117                 GOTO(fini_oit, rc = 0);
1118
1119         if (!list_empty(&lfsck->li_list_scan) ||
1120             list_empty(&lfsck->li_list_double_scan))
1121                 rc = lfsck_master_oit_engine(env, lfsck);
1122         else
1123                 rc = 1;
1124
1125         CDEBUG(D_LFSCK, "LFSCK exit: oit_flags = %#x, dir_flags = %#x, "
1126                "oit_cookie = "LPU64", dir_cookie = "LPX64", parent = "DFID
1127                ", pid = %d, rc = %d\n", lfsck->li_args_oit, lfsck->li_args_dir,
1128                lfsck->li_pos_checkpoint.lp_oit_cookie,
1129                lfsck->li_pos_checkpoint.lp_dir_cookie,
1130                PFID(&lfsck->li_pos_checkpoint.lp_dir_parent),
1131                current_pid(), rc);
1132
1133         if (!OBD_FAIL_CHECK(OBD_FAIL_LFSCK_CRASH))
1134                 rc = lfsck_post(env, lfsck, rc);
1135         else
1136                 lfsck_close_dir(env, lfsck, rc);
1137
1138 fini_oit:
1139         lfsck_di_oit_put(env, lfsck);
1140         oit_iops->fini(env, oit_di);
1141         if (rc == 1) {
1142                 if (!list_empty(&lfsck->li_list_double_scan))
1143                         rc = lfsck_double_scan(env, lfsck);
1144                 else
1145                         rc = 0;
1146         } else {
1147                 lfsck_quit(env, lfsck);
1148         }
1149
1150         /* XXX: Purge the pinned objects in the future. */
1151
1152 fini_args:
1153         spin_lock(&lfsck->li_lock);
1154         thread_set_flags(thread, SVC_STOPPED);
1155         spin_unlock(&lfsck->li_lock);
1156         wake_up_all(&thread->t_ctl_waitq);
1157         lfsck_thread_args_fini(lta);
1158         return rc;
1159 }
1160
1161 static inline bool lfsck_assistant_req_empty(struct lfsck_assistant_data *lad)
1162 {
1163         bool empty = false;
1164
1165         spin_lock(&lad->lad_lock);
1166         if (list_empty(&lad->lad_req_list))
1167                 empty = true;
1168         spin_unlock(&lad->lad_lock);
1169
1170         return empty;
1171 }
1172
1173 /**
1174  * Query the LFSCK status from the instatnces on remote servers.
1175  *
1176  * The LFSCK assistant thread queries the LFSCK instances on other
1177  * servers (MDT/OST) about their status, such as whether they have
1178  * finished the phase1/phase2 scanning or not, and so on.
1179  *
1180  * \param[in] env       pointer to the thread context
1181  * \param[in] com       pointer to the lfsck component
1182  *
1183  * \retval              0 for success
1184  * \retval              negative error number on failure
1185  */
1186 static int lfsck_assistant_query_others(const struct lu_env *env,
1187                                         struct lfsck_component *com)
1188 {
1189         struct lfsck_thread_info          *info  = lfsck_env_info(env);
1190         struct lfsck_request              *lr    = &info->lti_lr;
1191         struct lfsck_async_interpret_args *laia  = &info->lti_laia;
1192         struct lfsck_instance             *lfsck = com->lc_lfsck;
1193         struct lfsck_assistant_data       *lad   = com->lc_data;
1194         struct ptlrpc_request_set         *set;
1195         struct lfsck_tgt_descs            *ltds;
1196         struct lfsck_tgt_desc             *ltd;
1197         struct list_head                  *phase_head;
1198         int                                rc    = 0;
1199         int                                rc1   = 0;
1200         ENTRY;
1201
1202         set = ptlrpc_prep_set();
1203         if (set == NULL)
1204                 RETURN(-ENOMEM);
1205
1206         lad->lad_touch_gen++;
1207         memset(lr, 0, sizeof(*lr));
1208         lr->lr_index = lfsck_dev_idx(lfsck->li_bottom);
1209         lr->lr_event = LE_QUERY;
1210         lr->lr_active = com->lc_type;
1211         laia->laia_com = com;
1212         laia->laia_lr = lr;
1213         laia->laia_shared = 0;
1214
1215         if (!list_empty(&lad->lad_mdt_phase1_list)) {
1216                 ltds = &lfsck->li_mdt_descs;
1217                 lr->lr_flags = 0;
1218                 phase_head = &lad->lad_mdt_phase1_list;
1219         } else if (com->lc_type != LFSCK_TYPE_LAYOUT) {
1220                 goto out;
1221         } else {
1222
1223 again:
1224                 ltds = &lfsck->li_ost_descs;
1225                 lr->lr_flags = LEF_TO_OST;
1226                 phase_head = &lad->lad_ost_phase1_list;
1227         }
1228
1229         laia->laia_ltds = ltds;
1230         spin_lock(&ltds->ltd_lock);
1231         while (!list_empty(phase_head)) {
1232                 struct list_head *phase_list;
1233                 __u32            *gen;
1234
1235                 if (com->lc_type == LFSCK_TYPE_LAYOUT) {
1236                         ltd = list_entry(phase_head->next,
1237                                          struct lfsck_tgt_desc,
1238                                          ltd_layout_phase_list);
1239                         phase_list = &ltd->ltd_layout_phase_list;
1240                         gen = &ltd->ltd_layout_gen;
1241                 } else {
1242                         ltd = list_entry(phase_head->next,
1243                                          struct lfsck_tgt_desc,
1244                                          ltd_namespace_phase_list);
1245                         phase_list = &ltd->ltd_namespace_phase_list;
1246                         gen = &ltd->ltd_namespace_gen;
1247                 }
1248
1249                 if (*gen == lad->lad_touch_gen)
1250                         break;
1251
1252                 *gen = lad->lad_touch_gen;
1253                 list_move_tail(phase_list, phase_head);
1254                 atomic_inc(&ltd->ltd_ref);
1255                 laia->laia_ltd = ltd;
1256                 spin_unlock(&ltds->ltd_lock);
1257                 rc = lfsck_async_request(env, ltd->ltd_exp, lr, set,
1258                                          lfsck_async_interpret_common,
1259                                          laia, LFSCK_QUERY);
1260                 if (rc != 0) {
1261                         CDEBUG(D_LFSCK, "%s: LFSCK assistant fail to query "
1262                                "%s %x for %s: rc = %d\n",
1263                                lfsck_lfsck2name(lfsck),
1264                                (lr->lr_flags & LEF_TO_OST) ? "OST" : "MDT",
1265                                ltd->ltd_index, lad->lad_name, rc);
1266                         lfsck_tgt_put(ltd);
1267                         rc1 = rc;
1268                 }
1269                 spin_lock(&ltds->ltd_lock);
1270         }
1271         spin_unlock(&ltds->ltd_lock);
1272
1273         rc = ptlrpc_set_wait(set);
1274         if (rc < 0) {
1275                 ptlrpc_set_destroy(set);
1276                 RETURN(rc);
1277         }
1278
1279         if (com->lc_type == LFSCK_TYPE_LAYOUT && !(lr->lr_flags & LEF_TO_OST) &&
1280             list_empty(&lad->lad_mdt_phase1_list))
1281                 goto again;
1282
1283 out:
1284         ptlrpc_set_destroy(set);
1285
1286         RETURN(rc1 != 0 ? rc1 : rc);
1287 }
1288
1289 /**
1290  * Notify the LFSCK event to the instatnces on remote servers.
1291  *
1292  * The LFSCK assistant thread notifies the LFSCK instances on other
1293  * servers (MDT/OST) about some events, such as start new scanning,
1294  * stop the scanning, this LFSCK instance will exit, and so on.
1295  *
1296  * \param[in] env       pointer to the thread context
1297  * \param[in] com       pointer to the lfsck component
1298  * \param[in] lr        pointer to the LFSCK event request
1299  *
1300  * \retval              0 for success
1301  * \retval              negative error number on failure
1302  */
1303 static int lfsck_assistant_notify_others(const struct lu_env *env,
1304                                          struct lfsck_component *com,
1305                                          struct lfsck_request *lr)
1306 {
1307         struct lfsck_thread_info          *info  = lfsck_env_info(env);
1308         struct lfsck_async_interpret_args *laia  = &info->lti_laia;
1309         struct lfsck_instance             *lfsck = com->lc_lfsck;
1310         struct lfsck_assistant_data       *lad   = com->lc_data;
1311         struct lfsck_bookmark             *bk    = &lfsck->li_bookmark_ram;
1312         struct ptlrpc_request_set         *set;
1313         struct lfsck_tgt_descs            *ltds;
1314         struct lfsck_tgt_desc             *ltd;
1315         struct lfsck_tgt_desc             *next;
1316         __u32                              idx;
1317         int                                rc    = 0;
1318         int                                rc1   = 0;
1319         ENTRY;
1320
1321         set = ptlrpc_prep_set();
1322         if (set == NULL)
1323                 RETURN(-ENOMEM);
1324
1325         lr->lr_index = lfsck_dev_idx(lfsck->li_bottom);
1326         lr->lr_active = com->lc_type;
1327         laia->laia_com = com;
1328         laia->laia_lr = lr;
1329         laia->laia_shared = 0;
1330
1331         switch (lr->lr_event) {
1332         case LE_START:
1333                 if (com->lc_type != LFSCK_TYPE_LAYOUT)
1334                         goto next;
1335
1336                 lr->lr_valid = LSV_SPEED_LIMIT | LSV_ERROR_HANDLE | LSV_DRYRUN |
1337                                LSV_ASYNC_WINDOWS | LSV_CREATE_OSTOBJ;
1338                 lr->lr_speed = bk->lb_speed_limit;
1339                 lr->lr_version = bk->lb_version;
1340                 lr->lr_param |= bk->lb_param;
1341                 lr->lr_async_windows = bk->lb_async_windows;
1342                 lr->lr_flags = LEF_TO_OST;
1343
1344                 /* Notify OSTs firstly, then handle other MDTs if needed. */
1345                 ltds = &lfsck->li_ost_descs;
1346                 laia->laia_ltds = ltds;
1347                 down_read(&ltds->ltd_rw_sem);
1348                 cfs_foreach_bit(ltds->ltd_tgts_bitmap, idx) {
1349                         ltd = lfsck_tgt_get(ltds, idx);
1350                         LASSERT(ltd != NULL);
1351
1352                         laia->laia_ltd = ltd;
1353                         ltd->ltd_layout_done = 0;
1354                         rc = lfsck_async_request(env, ltd->ltd_exp, lr, set,
1355                                         lfsck_async_interpret_common,
1356                                         laia, LFSCK_NOTIFY);
1357                         if (rc != 0) {
1358                                 lfsck_lad_set_bitmap(env, com, idx);
1359                                 CDEBUG(D_LFSCK, "%s: LFSCK assistant fail to "
1360                                        "notify OST %x for %s start: rc = %d\n",
1361                                        lfsck_lfsck2name(lfsck), idx,
1362                                        lad->lad_name, rc);
1363                                 lfsck_tgt_put(ltd);
1364                         }
1365                 }
1366                 up_read(&ltds->ltd_rw_sem);
1367
1368                 /* Sync up */
1369                 rc = ptlrpc_set_wait(set);
1370                 if (rc < 0) {
1371                         ptlrpc_set_destroy(set);
1372                         RETURN(rc);
1373                 }
1374
1375 next:
1376                 if (!(bk->lb_param & LPF_ALL_TGT))
1377                         break;
1378
1379                 /* link other MDT targets locallly. */
1380                 ltds = &lfsck->li_mdt_descs;
1381                 spin_lock(&ltds->ltd_lock);
1382                 if (com->lc_type == LFSCK_TYPE_LAYOUT) {
1383                         cfs_foreach_bit(ltds->ltd_tgts_bitmap, idx) {
1384                                 ltd = LTD_TGT(ltds, idx);
1385                                 LASSERT(ltd != NULL);
1386
1387                                 if (!list_empty(&ltd->ltd_layout_list))
1388                                         continue;
1389
1390                                 list_add_tail(&ltd->ltd_layout_list,
1391                                               &lad->lad_mdt_list);
1392                                 list_add_tail(&ltd->ltd_layout_phase_list,
1393                                               &lad->lad_mdt_phase1_list);
1394                         }
1395                 } else {
1396                         cfs_foreach_bit(ltds->ltd_tgts_bitmap, idx) {
1397                                 ltd = LTD_TGT(ltds, idx);
1398                                 LASSERT(ltd != NULL);
1399
1400                                 if (!list_empty(&ltd->ltd_namespace_list))
1401                                         continue;
1402
1403                                 list_add_tail(&ltd->ltd_namespace_list,
1404                                               &lad->lad_mdt_list);
1405                                 list_add_tail(&ltd->ltd_namespace_phase_list,
1406                                               &lad->lad_mdt_phase1_list);
1407                         }
1408                 }
1409                 spin_unlock(&ltds->ltd_lock);
1410                 break;
1411         case LE_STOP:
1412         case LE_PHASE2_DONE:
1413         case LE_PEER_EXIT: {
1414                 struct list_head *phase_head;
1415
1416                 /* Handle other MDTs firstly if needed, then notify the OSTs. */
1417                 if (bk->lb_param & LPF_ALL_TGT) {
1418                         phase_head = &lad->lad_mdt_list;
1419                         ltds = &lfsck->li_mdt_descs;
1420                         if (lr->lr_event == LE_STOP) {
1421                                 /* unlink other MDT targets locallly. */
1422                                 spin_lock(&ltds->ltd_lock);
1423                                 if (com->lc_type == LFSCK_TYPE_LAYOUT) {
1424                                         list_for_each_entry_safe(ltd, next,
1425                                                 phase_head, ltd_layout_list) {
1426                                                 list_del_init(
1427                                                 &ltd->ltd_layout_phase_list);
1428                                                 list_del_init(
1429                                                 &ltd->ltd_layout_list);
1430                                         }
1431                                 } else {
1432                                         list_for_each_entry_safe(ltd, next,
1433                                                         phase_head,
1434                                                         ltd_namespace_list) {
1435                                                 list_del_init(
1436                                                 &ltd->ltd_namespace_phase_list);
1437                                                 list_del_init(
1438                                                 &ltd->ltd_namespace_list);
1439                                         }
1440                                 }
1441                                 spin_unlock(&ltds->ltd_lock);
1442
1443                                 if (com->lc_type != LFSCK_TYPE_LAYOUT)
1444                                         break;
1445
1446                                 lr->lr_flags |= LEF_TO_OST;
1447                                 phase_head = &lad->lad_ost_list;
1448                                 ltds = &lfsck->li_ost_descs;
1449                         } else {
1450                                 lr->lr_flags &= ~LEF_TO_OST;
1451                         }
1452                 } else if (com->lc_type != LFSCK_TYPE_LAYOUT) {
1453                         break;
1454                 } else {
1455                         lr->lr_flags |= LEF_TO_OST;
1456                         phase_head = &lad->lad_ost_list;
1457                         ltds = &lfsck->li_ost_descs;
1458                 }
1459
1460 again:
1461                 laia->laia_ltds = ltds;
1462                 spin_lock(&ltds->ltd_lock);
1463                 while (!list_empty(phase_head)) {
1464                         if (com->lc_type == LFSCK_TYPE_LAYOUT) {
1465                                 ltd = list_entry(phase_head->next,
1466                                                  struct lfsck_tgt_desc,
1467                                                  ltd_layout_list);
1468                                 if (!list_empty(&ltd->ltd_layout_phase_list))
1469                                         list_del_init(
1470                                                 &ltd->ltd_layout_phase_list);
1471                                 list_del_init(&ltd->ltd_layout_list);
1472                         } else {
1473                                 ltd = list_entry(phase_head->next,
1474                                                  struct lfsck_tgt_desc,
1475                                                  ltd_namespace_list);
1476                                 if (!list_empty(&ltd->ltd_namespace_phase_list))
1477                                         list_del_init(
1478                                                 &ltd->ltd_namespace_phase_list);
1479                                 list_del_init(&ltd->ltd_namespace_list);
1480                         }
1481                         atomic_inc(&ltd->ltd_ref);
1482                         laia->laia_ltd = ltd;
1483                         spin_unlock(&ltds->ltd_lock);
1484                         rc = lfsck_async_request(env, ltd->ltd_exp, lr, set,
1485                                         lfsck_async_interpret_common,
1486                                         laia, LFSCK_NOTIFY);
1487                         if (rc != 0) {
1488                                 CDEBUG(D_LFSCK, "%s: LFSCK assistant fail to "
1489                                        "notify %s %x for %s stop/phase2_done/"
1490                                        "peer_exit: rc = %d\n",
1491                                        lfsck_lfsck2name(lfsck),
1492                                        (lr->lr_flags & LEF_TO_OST) ?
1493                                        "OST" : "MDT", ltd->ltd_index,
1494                                        lad->lad_name, rc);
1495                                 lfsck_tgt_put(ltd);
1496                         }
1497                         spin_lock(&ltds->ltd_lock);
1498                 }
1499                 spin_unlock(&ltds->ltd_lock);
1500
1501                 rc = ptlrpc_set_wait(set);
1502                 if (rc < 0) {
1503                         ptlrpc_set_destroy(set);
1504                         RETURN(rc);
1505                 }
1506
1507                 if (com->lc_type == LFSCK_TYPE_LAYOUT &&
1508                     !(lr->lr_flags & LEF_TO_OST)) {
1509                         lr->lr_flags |= LEF_TO_OST;
1510                         phase_head = &lad->lad_ost_list;
1511                         ltds = &lfsck->li_ost_descs;
1512                         goto again;
1513                 }
1514                 break;
1515         }
1516         case LE_PHASE1_DONE:
1517                 lad->lad_ops->la_sync_failures(env, com, lr);
1518                 lad->lad_touch_gen++;
1519                 ltds = &lfsck->li_mdt_descs;
1520                 laia->laia_ltds = ltds;
1521                 spin_lock(&ltds->ltd_lock);
1522                 while (!list_empty(&lad->lad_mdt_list)) {
1523                         struct list_head *list;
1524                         __u32            *gen;
1525
1526                         if (com->lc_type == LFSCK_TYPE_LAYOUT) {
1527                                 ltd = list_entry(lad->lad_mdt_list.next,
1528                                                  struct lfsck_tgt_desc,
1529                                                  ltd_layout_list);
1530                                 list = &ltd->ltd_layout_list;
1531                                 gen = &ltd->ltd_layout_gen;
1532                         } else {
1533                                 struct lfsck_namespace *ns = com->lc_file_ram;
1534
1535                                 ltd = list_entry(lad->lad_mdt_list.next,
1536                                                  struct lfsck_tgt_desc,
1537                                                  ltd_namespace_list);
1538                                 list = &ltd->ltd_namespace_list;
1539                                 gen = &ltd->ltd_namespace_gen;
1540                                 lr->lr_flags2 = ns->ln_flags & ~LF_INCOMPLETE;
1541                         }
1542
1543                         if (*gen == lad->lad_touch_gen)
1544                                 break;
1545
1546                         *gen = lad->lad_touch_gen;
1547                         list_move_tail(list, &lad->lad_mdt_list);
1548                         if (ltd->ltd_namespace_failed)
1549                                 continue;
1550
1551                         atomic_inc(&ltd->ltd_ref);
1552                         laia->laia_ltd = ltd;
1553                         spin_unlock(&ltds->ltd_lock);
1554                         rc = lfsck_async_request(env, ltd->ltd_exp, lr, set,
1555                                         lfsck_async_interpret_common,
1556                                         laia, LFSCK_NOTIFY);
1557                         if (rc != 0) {
1558                                 CDEBUG(D_LFSCK, "%s: LFSCK assistant fail to "
1559                                        "notify MDT %x for %s phase1 done: "
1560                                        "rc = %d\n", lfsck_lfsck2name(lfsck),
1561                                        ltd->ltd_index, lad->lad_name, rc);
1562                                 lfsck_tgt_put(ltd);
1563                         }
1564                         spin_lock(&ltds->ltd_lock);
1565                 }
1566                 spin_unlock(&ltds->ltd_lock);
1567                 break;
1568         default:
1569                 CDEBUG(D_LFSCK, "%s: LFSCK assistant unexpected LFSCK event: "
1570                        "rc = %d\n", lfsck_lfsck2name(lfsck), lr->lr_event);
1571                 rc = -EINVAL;
1572                 break;
1573         }
1574
1575         rc1 = ptlrpc_set_wait(set);
1576         ptlrpc_set_destroy(set);
1577
1578         RETURN(rc != 0 ? rc : rc1);
1579 }
1580
1581 /**
1582  * The LFSCK assistant thread is triggered by the LFSCK main engine.
1583  * They co-work together as an asynchronous pipeline: the LFSCK main
1584  * engine scans the system and pre-fetches the objects, attributes,
1585  * or name entries, etc, and pushes them into the pipeline as input
1586  * requests for the LFSCK assistant thread; on the other end of the
1587  * pipeline, the LFSCK assistant thread performs the real check and
1588  * repair for every request from the main engine.
1589  *
1590  * Generally, the assistant engine may be blocked when check/repair
1591  * something, so the LFSCK main engine will run some faster. On the
1592  * other hand, the LFSCK main engine will drive multiple assistant
1593  * threads in parallel, means for each LFSCK component on the master
1594  * (such as layout LFSCK, namespace LFSCK), there is an independent
1595  * LFSCK assistant thread. So under such 1:N multiple asynchronous
1596  * pipelines mode, the whole LFSCK performance will be much better
1597  * than check/repair everything by the LFSCK main engine itself.
1598  */
1599 int lfsck_assistant_engine(void *args)
1600 {
1601         struct lfsck_thread_args          *lta     = args;
1602         struct lu_env                     *env     = &lta->lta_env;
1603         struct lfsck_component            *com     = lta->lta_com;
1604         struct lfsck_instance             *lfsck   = lta->lta_lfsck;
1605         struct lfsck_bookmark             *bk      = &lfsck->li_bookmark_ram;
1606         struct lfsck_position             *pos     = &com->lc_pos_start;
1607         struct lfsck_thread_info          *info    = lfsck_env_info(env);
1608         struct lfsck_request              *lr      = &info->lti_lr;
1609         struct lfsck_assistant_data       *lad     = com->lc_data;
1610         struct ptlrpc_thread              *mthread = &lfsck->li_thread;
1611         struct ptlrpc_thread              *athread = &lad->lad_thread;
1612         struct lfsck_assistant_operations *lao     = lad->lad_ops;
1613         struct lfsck_assistant_req        *lar;
1614         struct l_wait_info                 lwi     = { 0 };
1615         int                                rc      = 0;
1616         int                                rc1     = 0;
1617         ENTRY;
1618
1619         CDEBUG(D_LFSCK, "%s: %s LFSCK assistant thread start\n",
1620                lfsck_lfsck2name(lfsck), lad->lad_name);
1621
1622         memset(lr, 0, sizeof(*lr));
1623         lr->lr_event = LE_START;
1624         if (pos->lp_oit_cookie <= 1)
1625                 lr->lr_param = LPF_RESET;
1626         rc = lfsck_assistant_notify_others(env, com, lr);
1627         if (rc != 0) {
1628                 CDEBUG(D_LFSCK, "%s: LFSCK assistant fail to notify others "
1629                        "to start %s: rc = %d\n",
1630                        lfsck_lfsck2name(lfsck), lad->lad_name, rc);
1631                 GOTO(fini, rc);
1632         }
1633
1634         spin_lock(&lad->lad_lock);
1635         thread_set_flags(athread, SVC_RUNNING);
1636         spin_unlock(&lad->lad_lock);
1637         wake_up_all(&mthread->t_ctl_waitq);
1638
1639         while (1) {
1640                 while (!list_empty(&lad->lad_req_list)) {
1641                         bool wakeup = false;
1642
1643                         if (unlikely(lad->lad_exit ||
1644                                      !thread_is_running(mthread)))
1645                                 GOTO(cleanup1, rc = lad->lad_post_result);
1646
1647                         lar = list_entry(lad->lad_req_list.next,
1648                                          struct lfsck_assistant_req,
1649                                          lar_list);
1650                         /* Only the lfsck_assistant_engine thread itself can
1651                          * remove the "lar" from the head of the list, LFSCK
1652                          * engine thread only inserts other new "lar" at the
1653                          * end of the list. So it is safe to handle current
1654                          * "lar" without the spin_lock. */
1655                         rc = lao->la_handler_p1(env, com, lar);
1656                         spin_lock(&lad->lad_lock);
1657                         list_del_init(&lar->lar_list);
1658                         lad->lad_prefetched--;
1659                         /* Wake up the main engine thread only when the list
1660                          * is empty or half of the prefetched items have been
1661                          * handled to avoid too frequent thread schedule. */
1662                         if (lad->lad_prefetched == 0 ||
1663                             (bk->lb_async_windows != 0 &&
1664                              bk->lb_async_windows / 2 ==
1665                              lad->lad_prefetched))
1666                                 wakeup = true;
1667                         spin_unlock(&lad->lad_lock);
1668                         if (wakeup)
1669                                 wake_up_all(&mthread->t_ctl_waitq);
1670
1671                         lao->la_req_fini(env, lar);
1672                         if (rc < 0 && bk->lb_param & LPF_FAILOUT)
1673                                 GOTO(cleanup1, rc);
1674                 }
1675
1676                 l_wait_event(athread->t_ctl_waitq,
1677                              !lfsck_assistant_req_empty(lad) ||
1678                              lad->lad_exit ||
1679                              lad->lad_to_post ||
1680                              lad->lad_to_double_scan,
1681                              &lwi);
1682
1683                 if (unlikely(lad->lad_exit))
1684                         GOTO(cleanup1, rc = lad->lad_post_result);
1685
1686                 if (!list_empty(&lad->lad_req_list))
1687                         continue;
1688
1689                 if (lad->lad_to_post) {
1690                         CDEBUG(D_LFSCK, "%s: %s LFSCK assistant thread post\n",
1691                                lfsck_lfsck2name(lfsck), lad->lad_name);
1692
1693                         if (unlikely(lad->lad_exit))
1694                                 GOTO(cleanup1, rc = lad->lad_post_result);
1695
1696                         lad->lad_to_post = 0;
1697                         LASSERT(lad->lad_post_result > 0);
1698
1699                         memset(lr, 0, sizeof(*lr));
1700                         lr->lr_event = LE_PHASE1_DONE;
1701                         lr->lr_status = lad->lad_post_result;
1702                         rc = lfsck_assistant_notify_others(env, com, lr);
1703                         if (rc != 0)
1704                                 CDEBUG(D_LFSCK, "%s: LFSCK assistant failed to "
1705                                        "notify others for %s post: rc = %d\n",
1706                                        lfsck_lfsck2name(lfsck),
1707                                        lad->lad_name, rc);
1708
1709                         /* Wakeup the master engine to go ahead. */
1710                         wake_up_all(&mthread->t_ctl_waitq);
1711                 }
1712
1713                 if (lad->lad_to_double_scan) {
1714                         lad->lad_to_double_scan = 0;
1715                         atomic_inc(&lfsck->li_double_scan_count);
1716                         lad->lad_in_double_scan = 1;
1717                         wake_up_all(&mthread->t_ctl_waitq);
1718
1719                         com->lc_new_checked = 0;
1720                         com->lc_new_scanned = 0;
1721                         com->lc_time_last_checkpoint = cfs_time_current();
1722                         com->lc_time_next_checkpoint =
1723                                 com->lc_time_last_checkpoint +
1724                                 cfs_time_seconds(LFSCK_CHECKPOINT_INTERVAL);
1725
1726                         /* Flush async updates before handling orphan. */
1727                         dt_sync(env, lfsck->li_next);
1728
1729                         CDEBUG(D_LFSCK, "%s: LFSCK assistant phase2 "
1730                                "scan start\n", lfsck_lfsck2name(lfsck));
1731
1732                         if (OBD_FAIL_CHECK(OBD_FAIL_LFSCK_NO_DOUBLESCAN))
1733                                 GOTO(cleanup2, rc = 0);
1734
1735                         while (lad->lad_in_double_scan) {
1736                                 rc = lfsck_assistant_query_others(env, com);
1737                                 if (lfsck_phase2_next_ready(lad))
1738                                         goto p2_next;
1739
1740                                 if (rc < 0)
1741                                         GOTO(cleanup2, rc);
1742
1743                                 /* Pull LFSCK status on related targets once
1744                                  * per 30 seconds if we are not notified. */
1745                                 lwi = LWI_TIMEOUT_INTERVAL(cfs_time_seconds(30),
1746                                                            cfs_time_seconds(1),
1747                                                            NULL, NULL);
1748                                 rc = l_wait_event(athread->t_ctl_waitq,
1749                                         lfsck_phase2_next_ready(lad) ||
1750                                         lad->lad_exit ||
1751                                         !thread_is_running(mthread),
1752                                         &lwi);
1753
1754                                 if (unlikely(lad->lad_exit ||
1755                                              !thread_is_running(mthread)))
1756                                         GOTO(cleanup2, rc = 0);
1757
1758                                 if (rc == -ETIMEDOUT)
1759                                         continue;
1760
1761                                 if (rc < 0)
1762                                         GOTO(cleanup2, rc);
1763
1764 p2_next:
1765                                 rc = lao->la_handler_p2(env, com);
1766                                 if (rc != 0)
1767                                         GOTO(cleanup2, rc);
1768
1769                                 if (unlikely(lad->lad_exit ||
1770                                              !thread_is_running(mthread)))
1771                                         GOTO(cleanup2, rc = 0);
1772                         }
1773                 }
1774         }
1775
1776 cleanup1:
1777         /* Cleanup the unfinished requests. */
1778         spin_lock(&lad->lad_lock);
1779         if (rc < 0)
1780                 lad->lad_assistant_status = rc;
1781
1782         if (lad->lad_exit && lad->lad_post_result <= 0)
1783                 lao->la_fill_pos(env, com, &lfsck->li_pos_checkpoint);
1784
1785         while (!list_empty(&lad->lad_req_list)) {
1786                 lar = list_entry(lad->lad_req_list.next,
1787                                  struct lfsck_assistant_req,
1788                                  lar_list);
1789                 list_del_init(&lar->lar_list);
1790                 lad->lad_prefetched--;
1791                 spin_unlock(&lad->lad_lock);
1792                 lao->la_req_fini(env, lar);
1793                 spin_lock(&lad->lad_lock);
1794         }
1795         spin_unlock(&lad->lad_lock);
1796
1797         LASSERTF(lad->lad_prefetched == 0, "unmatched prefeteched objs %d\n",
1798                  lad->lad_prefetched);
1799
1800 cleanup2:
1801         memset(lr, 0, sizeof(*lr));
1802         if (rc > 0) {
1803                 lr->lr_event = LE_PHASE2_DONE;
1804                 lr->lr_status = rc;
1805         } else if (rc == 0) {
1806                 if (lfsck->li_flags & LPF_ALL_TGT) {
1807                         lr->lr_event = LE_STOP;
1808                         lr->lr_status = LS_STOPPED;
1809                 } else {
1810                         lr->lr_event = LE_PEER_EXIT;
1811                         switch (lfsck->li_status) {
1812                         case LS_PAUSED:
1813                         case LS_CO_PAUSED:
1814                                 lr->lr_status = LS_CO_PAUSED;
1815                                 break;
1816                         case LS_STOPPED:
1817                         case LS_CO_STOPPED:
1818                                 lr->lr_status = LS_CO_STOPPED;
1819                                 break;
1820                         default:
1821                                 CDEBUG(D_LFSCK, "%s: LFSCK assistant unknown "
1822                                        "status: rc = %d\n",
1823                                        lfsck_lfsck2name(lfsck),
1824                                        lfsck->li_status);
1825                                 lr->lr_status = LS_CO_FAILED;
1826                                 break;
1827                         }
1828                 }
1829         } else {
1830                 if (lfsck->li_flags & LPF_ALL_TGT) {
1831                         lr->lr_event = LE_STOP;
1832                         lr->lr_status = LS_FAILED;
1833                 } else {
1834                         lr->lr_event = LE_PEER_EXIT;
1835                         lr->lr_status = LS_CO_FAILED;
1836                 }
1837         }
1838
1839         rc1 = lfsck_assistant_notify_others(env, com, lr);
1840         if (rc1 != 0) {
1841                 CDEBUG(D_LFSCK, "%s: LFSCK assistant failed to notify "
1842                        "others for %s quit: rc = %d\n",
1843                        lfsck_lfsck2name(lfsck), lad->lad_name, rc1);
1844                 rc = rc1;
1845         }
1846
1847         /* Flush async updates before exit. */
1848         dt_sync(env, lfsck->li_next);
1849
1850         /* Under force exit case, some requests may be just freed without
1851          * verification, those objects should be re-handled when next run.
1852          * So not update the on-disk trace file under such case. */
1853         if (lad->lad_in_double_scan) {
1854                 if (!lad->lad_exit)
1855                         rc1 = lao->la_double_scan_result(env, com, rc);
1856
1857                 CDEBUG(D_LFSCK, "%s: LFSCK assistant phase2 scan "
1858                        "finished: rc = %d\n",
1859                        lfsck_lfsck2name(lfsck), rc1 != 0 ? rc1 : rc);
1860         }
1861
1862 fini:
1863         if (lad->lad_in_double_scan)
1864                 atomic_dec(&lfsck->li_double_scan_count);
1865
1866         spin_lock(&lad->lad_lock);
1867         lad->lad_assistant_status = (rc1 != 0 ? rc1 : rc);
1868         thread_set_flags(athread, SVC_STOPPED);
1869         wake_up_all(&mthread->t_ctl_waitq);
1870         spin_unlock(&lad->lad_lock);
1871
1872         CDEBUG(D_LFSCK, "%s: %s LFSCK assistant thread exit: rc = %d\n",
1873                lfsck_lfsck2name(lfsck), lad->lad_name,
1874                lad->lad_assistant_status);
1875
1876         lfsck_thread_args_fini(lta);
1877
1878         return rc;
1879 }