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LU-6895 lfsck: not destroy directory when fix FID-in-dirent
[fs/lustre-release.git] / lustre / lfsck / lfsck_namespace.c
index 6641db8..44ead75 100644 (file)
@@ -20,7 +20,7 @@
  * GPL HEADER END
  */
 /*
- * Copyright (c) 2012, 2013, Intel Corporation.
+ * Copyright (c) 2013, 2014, Intel Corporation.
  */
 /*
  * lustre/lfsck/lfsck_namespace.c
 
 #include "lfsck_internal.h"
 
-#define LFSCK_NAMESPACE_MAGIC  0xA0629D03
+#define LFSCK_NAMESPACE_MAGIC_V1       0xA0629D03
+#define LFSCK_NAMESPACE_MAGIC_V2       0xA0621A0B
+
+/* For Lustre-2.x (x <= 6), the namespace LFSCK used LFSCK_NAMESPACE_MAGIC_V1
+ * as the trace file magic. When downgrade to such old release, the old LFSCK
+ * will not recognize the new LFSCK_NAMESPACE_MAGIC_V2 in the new trace file,
+ * then it will reset the whole LFSCK, and will not cause start failure. The
+ * similar case will happen when upgrade from such old release. */
+#define LFSCK_NAMESPACE_MAGIC          LFSCK_NAMESPACE_MAGIC_V2
 
 enum lfsck_nameentry_check {
        LFSCK_NAMEENTRY_DEAD            = 1, /* The object has been unlinked. */
@@ -49,10 +57,9 @@ enum lfsck_nameentry_check {
        LFSCK_NAMEENTRY_RECREATED       = 3, /* The entry has been recreated. */
 };
 
-static const char lfsck_namespace_name[] = "lfsck_namespace";
-
 static struct lfsck_namespace_req *
 lfsck_namespace_assistant_req_init(struct lfsck_instance *lfsck,
+                                  struct lfsck_assistant_object *lso,
                                   struct lu_dirent *ent, __u16 type)
 {
        struct lfsck_namespace_req *lnr;
@@ -64,10 +71,9 @@ lfsck_namespace_assistant_req_init(struct lfsck_instance *lfsck,
                return ERR_PTR(-ENOMEM);
 
        INIT_LIST_HEAD(&lnr->lnr_lar.lar_list);
-       lnr->lnr_obj = lfsck_object_get(lfsck->li_obj_dir);
+       lnr->lnr_lar.lar_parent = lfsck_assistant_object_get(lso);
        lnr->lnr_lmv = lfsck_lmv_get(lfsck->li_lmv);
        lnr->lnr_fid = ent->lde_fid;
-       lnr->lnr_oit_cookie = lfsck->li_pos_current.lp_oit_cookie;
        lnr->lnr_dir_cookie = ent->lde_hash;
        lnr->lnr_attr = ent->lde_attrs;
        lnr->lnr_size = size;
@@ -87,7 +93,7 @@ static void lfsck_namespace_assistant_req_fini(const struct lu_env *env,
        if (lnr->lnr_lmv != NULL)
                lfsck_lmv_put(env, lnr->lnr_lmv);
 
-       lu_object_put(env, &lnr->lnr_obj->do_lu);
+       lfsck_assistant_object_put(env, lar->lar_parent);
        OBD_FREE(lnr, lnr->lnr_size);
 }
 
@@ -306,7 +312,7 @@ static int lfsck_namespace_load_bitmap(const struct lu_env *env,
        size = (ns->ln_bitmap_size + 7) >> 3;
        rc = dt_xattr_get(env, obj,
                          lfsck_buf_get(env, bitmap->data, size),
-                         XATTR_NAME_LFSCK_BITMAP, BYPASS_CAPA);
+                         XATTR_NAME_LFSCK_BITMAP);
        if (rc != size)
                RETURN(rc >= 0 ? -EINVAL : rc);
 
@@ -319,9 +325,19 @@ static int lfsck_namespace_load_bitmap(const struct lu_env *env,
 }
 
 /**
- * \retval +ve: the lfsck_namespace is broken, the caller should reset it.
- * \retval 0: succeed.
- * \retval -ve: failed cases.
+ * Load namespace LFSCK statistics information from the trace file.
+ *
+ * For old release (Lustre-2.6 or older), the statistics information was
+ * stored as XATTR_NAME_LFSCK_NAMESPACE_OLD EA. But in Lustre-2.7, we need
+ * more statistics information. To avoid confusing old MDT when downgrade,
+ * Lustre-2.7 stores the namespace LFSCK statistics information as new
+ * XATTR_NAME_LFSCK_NAMESPACE EA.
+ *
+ * \param[in] env      pointer to the thread context
+ * \param[in] com      pointer to the lfsck component
+ *
+ * \retval             0 for success
+ * \retval             negative error number on failure
  */
 static int lfsck_namespace_load(const struct lu_env *env,
                                struct lfsck_component *com)
@@ -331,7 +347,7 @@ static int lfsck_namespace_load(const struct lu_env *env,
 
        rc = dt_xattr_get(env, com->lc_obj,
                          lfsck_buf_get(env, com->lc_file_disk, len),
-                         XATTR_NAME_LFSCK_NAMESPACE, BYPASS_CAPA);
+                         XATTR_NAME_LFSCK_NAMESPACE);
        if (rc == len) {
                struct lfsck_namespace *ns = com->lc_file_ram;
 
@@ -341,7 +357,7 @@ static int lfsck_namespace_load(const struct lu_env *env,
                        CDEBUG(D_LFSCK, "%s: invalid lfsck_namespace magic "
                               "%#x != %#x\n", lfsck_lfsck2name(com->lc_lfsck),
                               ns->ln_magic, LFSCK_NAMESPACE_MAGIC);
-                       rc = 1;
+                       rc = -ESTALE;
                } else {
                        rc = 0;
                }
@@ -350,23 +366,36 @@ static int lfsck_namespace_load(const struct lu_env *env,
                       "expected = %d: rc = %d\n",
                       lfsck_lfsck2name(com->lc_lfsck), len, rc);
                if (rc >= 0)
-                       rc = 1;
+                       rc = -ESTALE;
+       } else {
+               /* Check whether it is old trace file or not.
+                * If yes, it should be reset via returning -ESTALE. */
+               rc = dt_xattr_get(env, com->lc_obj,
+                                 lfsck_buf_get(env, com->lc_file_disk, len),
+                                 XATTR_NAME_LFSCK_NAMESPACE_OLD);
+               if (rc >= 0)
+                       rc = -ESTALE;
        }
+
        return rc;
 }
 
 static int lfsck_namespace_store(const struct lu_env *env,
-                                struct lfsck_component *com)
+                                struct lfsck_component *com, bool init)
 {
        struct dt_object                *obj    = com->lc_obj;
        struct lfsck_instance           *lfsck  = com->lc_lfsck;
        struct lfsck_namespace          *ns     = com->lc_file_ram;
        struct lfsck_assistant_data     *lad    = com->lc_data;
+       struct dt_device                *dev    = lfsck_obj2dev(obj);
        cfs_bitmap_t                    *bitmap = NULL;
        struct thandle                  *handle;
        __u32                            nbits  = 0;
        int                              len    = com->lc_file_size;
        int                              rc;
+#if LUSTRE_VERSION_CODE < OBD_OCD_VERSION(2, 8, 53, 0)
+       struct lu_buf            tbuf   = { &len, sizeof(len) };
+#endif
        ENTRY;
 
        if (lad != NULL) {
@@ -380,7 +409,7 @@ static int lfsck_namespace_store(const struct lu_env *env,
        ns->ln_bitmap_size = nbits;
        lfsck_namespace_cpu_to_le((struct lfsck_namespace *)com->lc_file_disk,
                                  ns);
-       handle = dt_trans_create(env, lfsck->li_bottom);
+       handle = dt_trans_create(env, dev);
        if (IS_ERR(handle))
                GOTO(log, rc = PTR_ERR(handle));
 
@@ -398,23 +427,43 @@ static int lfsck_namespace_store(const struct lu_env *env,
                        GOTO(out, rc);
        }
 
-       rc = dt_trans_start_local(env, lfsck->li_bottom, handle);
+#if LUSTRE_VERSION_CODE < OBD_OCD_VERSION(2, 8, 53, 0)
+       /* To be compatible with old Lustre-2.x MDT (x <= 6), generate dummy
+        * XATTR_NAME_LFSCK_NAMESPACE_OLD EA, then when downgrade to Lustre-2.x,
+        * the old LFSCK will find "invalid" XATTR_NAME_LFSCK_NAMESPACE_OLD EA,
+        * then reset the namespace LFSCK trace file. */
+       if (init) {
+               rc = dt_declare_xattr_set(env, obj, &tbuf,
+                                         XATTR_NAME_LFSCK_NAMESPACE_OLD,
+                                         LU_XATTR_CREATE, handle);
+               if (rc != 0)
+                       GOTO(out, rc);
+       }
+#endif
+
+       rc = dt_trans_start_local(env, dev, handle);
        if (rc != 0)
                GOTO(out, rc);
 
        rc = dt_xattr_set(env, obj,
                          lfsck_buf_get(env, com->lc_file_disk, len),
-                         XATTR_NAME_LFSCK_NAMESPACE, 0, handle, BYPASS_CAPA);
+                         XATTR_NAME_LFSCK_NAMESPACE, 0, handle);
        if (rc == 0 && bitmap != NULL)
                rc = dt_xattr_set(env, obj,
                                  lfsck_buf_get(env, bitmap->data, nbits >> 3),
-                                 XATTR_NAME_LFSCK_BITMAP, 0, handle,
-                                 BYPASS_CAPA);
+                                 XATTR_NAME_LFSCK_BITMAP, 0, handle);
+
+#if LUSTRE_VERSION_CODE < OBD_OCD_VERSION(2, 8, 53, 0)
+       if (rc == 0 && init)
+               rc = dt_xattr_set(env, obj, &tbuf,
+                                 XATTR_NAME_LFSCK_NAMESPACE_OLD,
+                                 LU_XATTR_CREATE, handle);
+#endif
 
        GOTO(out, rc);
 
 out:
-       dt_trans_stop(env, lfsck->li_bottom, handle);
+       dt_trans_stop(env, dev, handle);
 
 log:
        if (rc != 0)
@@ -423,6 +472,64 @@ log:
        return rc;
 }
 
+static struct dt_object *
+lfsck_namespace_load_one_trace_file(const struct lu_env *env,
+                                   struct lfsck_component *com,
+                                   struct dt_object *parent,
+                                   const char *name, bool reset)
+{
+       struct lfsck_instance   *lfsck = com->lc_lfsck;
+       struct dt_object        *obj;
+       int                      rc;
+
+       if (reset) {
+               rc = local_object_unlink(env, lfsck->li_bottom, parent, name);
+               if (rc != 0 && rc != -ENOENT)
+                       return ERR_PTR(rc);
+       }
+
+       obj = local_index_find_or_create(env, lfsck->li_los, parent, name,
+                                        S_IFREG | S_IRUGO | S_IWUSR,
+                                        &dt_lfsck_features);
+
+       return obj;
+}
+
+static int lfsck_namespace_load_sub_trace_files(const struct lu_env *env,
+                                               struct lfsck_component *com,
+                                               bool reset)
+{
+       char                            *name = lfsck_env_info(env)->lti_key;
+       struct lfsck_sub_trace_obj      *lsto;
+       struct dt_object                *obj;
+       int                              rc;
+       int                              i;
+
+       for (i = 0, lsto = &com->lc_sub_trace_objs[0];
+            i < LFSCK_STF_COUNT; i++, lsto++) {
+               snprintf(name, NAME_MAX, "%s_%02d", LFSCK_NAMESPACE, i);
+               if (lsto->lsto_obj != NULL) {
+                       if (!reset)
+                               continue;
+
+                       lfsck_object_put(env, lsto->lsto_obj);
+                       lsto->lsto_obj = NULL;
+               }
+
+               obj = lfsck_namespace_load_one_trace_file(env, com,
+                               com->lc_lfsck->li_lfsck_dir, name, reset);
+               if (IS_ERR(obj))
+                       return PTR_ERR(obj);
+
+               lsto->lsto_obj = obj;
+               rc = obj->do_ops->do_index_try(env, obj, &dt_lfsck_features);
+               if (rc != 0)
+                       return rc;
+       }
+
+       return 0;
+}
+
 static int lfsck_namespace_init(const struct lu_env *env,
                                struct lfsck_component *com)
 {
@@ -433,8 +540,11 @@ static int lfsck_namespace_init(const struct lu_env *env,
        ns->ln_magic = LFSCK_NAMESPACE_MAGIC;
        ns->ln_status = LS_INIT;
        down_write(&com->lc_sem);
-       rc = lfsck_namespace_store(env, com);
+       rc = lfsck_namespace_store(env, com, true);
        up_write(&com->lc_sem);
+       if (rc == 0)
+               rc = lfsck_namespace_load_sub_trace_files(env, com, true);
+
        return rc;
 }
 
@@ -447,7 +557,7 @@ static int lfsck_namespace_init(const struct lu_env *env,
  *                     trace file
  * \param[in] add      true if add new flags, otherwise remove flags
  *
- * \retval             0 for succeed or nothing to be done
+ * \retval             0 for success or nothing to be done
  * \retval             negative error number on failure
  */
 int lfsck_namespace_trace_update(const struct lu_env *env,
@@ -456,10 +566,11 @@ int lfsck_namespace_trace_update(const struct lu_env *env,
                                 const __u8 flags, bool add)
 {
        struct lfsck_instance   *lfsck  = com->lc_lfsck;
-       struct dt_object        *obj    = com->lc_obj;
+       struct dt_object        *obj;
        struct lu_fid           *key    = &lfsck_env_info(env)->lti_fid3;
-       struct dt_device        *dev    = lfsck->li_bottom;
+       struct dt_device        *dev;
        struct thandle          *th     = NULL;
+       int                      idx;
        int                      rc     = 0;
        __u8                     old    = 0;
        __u8                     new    = 0;
@@ -467,10 +578,16 @@ int lfsck_namespace_trace_update(const struct lu_env *env,
 
        LASSERT(flags != 0);
 
-       down_write(&com->lc_sem);
+       if (unlikely(!fid_is_sane(fid)))
+               RETURN(0);
+
+       idx = lfsck_sub_trace_file_fid2idx(fid);
+       obj = com->lc_sub_trace_objs[idx].lsto_obj;
+       dev = lfsck_obj2dev(obj);
+       mutex_lock(&com->lc_sub_trace_objs[idx].lsto_mutex);
        fid_cpu_to_be(key, fid);
        rc = dt_lookup(env, obj, (struct dt_rec *)&old,
-                      (const struct dt_key *)key, BYPASS_CAPA);
+                      (const struct dt_key *)key);
        if (rc == -ENOENT) {
                if (!add)
                        GOTO(unlock, rc = 0);
@@ -517,15 +634,14 @@ int lfsck_namespace_trace_update(const struct lu_env *env,
                GOTO(log, rc);
 
        if (old != 0) {
-               rc = dt_delete(env, obj, (const struct dt_key *)key,
-                              th, BYPASS_CAPA);
+               rc = dt_delete(env, obj, (const struct dt_key *)key, th);
                if (rc != 0)
                        GOTO(log, rc);
        }
 
        if (new != 0) {
                rc = dt_insert(env, obj, (const struct dt_rec *)&new,
-                              (const struct dt_key *)key, th, BYPASS_CAPA, 1);
+                              (const struct dt_key *)key, th, 1);
                if (rc != 0)
                        GOTO(log, rc);
        }
@@ -542,7 +658,7 @@ log:
               (__u32)flags, (__u32)old, (__u32)new, rc);
 
 unlock:
-       up_write(&com->lc_sem);
+       mutex_unlock(&com->lc_sub_trace_objs[idx].lsto_mutex);
 
        return rc;
 }
@@ -559,7 +675,7 @@ int lfsck_namespace_check_exist(const struct lu_env *env,
                RETURN(LFSCK_NAMEENTRY_DEAD);
 
        rc = dt_lookup(env, dir, (struct dt_rec *)fid,
-                      (const struct dt_key *)name, BYPASS_CAPA);
+                      (const struct dt_key *)name);
        if (rc == -ENOENT)
                RETURN(LFSCK_NAMEENTRY_REMOVED);
 
@@ -601,11 +717,10 @@ int __lfsck_links_read(const struct lu_env *env, struct dt_object *obj,
        if (!dt_object_exists(obj))
                return -ENOENT;
 
-       rc = dt_xattr_get(env, obj, ldata->ld_buf, XATTR_NAME_LINK, BYPASS_CAPA);
+       rc = dt_xattr_get(env, obj, ldata->ld_buf, XATTR_NAME_LINK);
        if (rc == -ERANGE) {
                /* Buf was too small, figure out what we need. */
-               rc = dt_xattr_get(env, obj, &LU_BUF_NULL, XATTR_NAME_LINK,
-                                 BYPASS_CAPA);
+               rc = dt_xattr_get(env, obj, &LU_BUF_NULL, XATTR_NAME_LINK);
                if (rc <= 0)
                        return rc;
 
@@ -613,8 +728,7 @@ int __lfsck_links_read(const struct lu_env *env, struct dt_object *obj,
                if (ldata->ld_buf->lb_buf == NULL)
                        return -ENOMEM;
 
-               rc = dt_xattr_get(env, obj, ldata->ld_buf, XATTR_NAME_LINK,
-                                 BYPASS_CAPA);
+               rc = dt_xattr_get(env, obj, ldata->ld_buf, XATTR_NAME_LINK);
        }
 
        if (rc > 0)
@@ -640,7 +754,7 @@ static int lfsck_namespace_links_remove(const struct lu_env *env,
                                        struct dt_object *obj)
 {
        struct lfsck_instance           *lfsck  = com->lc_lfsck;
-       struct dt_device                *dev    = lfsck->li_bottom;
+       struct dt_device                *dev    = lfsck_obj2dev(obj);
        struct thandle                  *th     = NULL;
        int                              rc     = 0;
        ENTRY;
@@ -666,7 +780,7 @@ static int lfsck_namespace_links_remove(const struct lu_env *env,
        if (lfsck->li_bookmark_ram.lb_param & LPF_DRYRUN)
                GOTO(unlock, rc = 0);
 
-       rc = dt_xattr_del(env, obj, XATTR_NAME_LINK, th, BYPASS_CAPA);
+       rc = dt_xattr_del(env, obj, XATTR_NAME_LINK, th);
 
        GOTO(unlock, rc);
 
@@ -697,8 +811,7 @@ static int lfsck_links_write(const struct lu_env *env, struct dt_object *obj,
                                                       ldata->ld_buf->lb_buf,
                                                       ldata->ld_leh->leh_len);
 
-       return dt_xattr_set(env, obj, buf, XATTR_NAME_LINK, 0, handle,
-                           BYPASS_CAPA);
+       return dt_xattr_set(env, obj, buf, XATTR_NAME_LINK, 0, handle);
 }
 
 static void lfsck_namespace_unpack_linkea_entry(struct linkea_data *ldata,
@@ -792,17 +905,17 @@ static int lfsck_namespace_insert_orphan(const struct lu_env *env,
        struct lfsck_thread_info        *info   = lfsck_env_info(env);
        struct lu_name                  *cname  = &info->lti_name;
        struct dt_insert_rec            *rec    = &info->lti_dt_rec;
-       struct lu_fid                   *tfid   = &info->lti_fid5;
-       struct lu_attr                  *la     = &info->lti_la3;
+       struct lu_attr                  *la     = &info->lti_la2;
        const struct lu_fid             *cfid   = lfsck_dto2fid(orphan);
        const struct lu_fid             *pfid;
+       struct lu_fid                    tfid;
        struct lfsck_instance           *lfsck  = com->lc_lfsck;
-       struct dt_device                *dev    = lfsck->li_bottom;
+       struct dt_device                *dev    = lfsck_obj2dev(orphan);
        struct dt_object                *parent;
        struct thandle                  *th     = NULL;
-       struct lustre_handle             plh    = { 0 };
+       struct lfsck_lock_handle        *pllh   = &info->lti_llh;
        struct lustre_handle             clh    = { 0 };
-       struct linkea_data               ldata  = { 0 };
+       struct linkea_data               ldata  = { NULL };
        struct lu_buf                    linkea_buf;
        int                              namelen;
        int                              idx    = 0;
@@ -811,35 +924,48 @@ static int lfsck_namespace_insert_orphan(const struct lu_env *env,
        ENTRY;
 
        cname->ln_name = NULL;
-       /* Create .lustre/lost+found/MDTxxxx when needed. */
-       if (unlikely(lfsck->li_lpf_obj == NULL)) {
-               rc = lfsck_create_lpf(env, lfsck);
-               if (rc != 0)
-                       GOTO(log, rc);
-       }
+       if (unlikely(lfsck->li_lpf_obj == NULL))
+               GOTO(log, rc = -ENXIO);
 
        parent = lfsck->li_lpf_obj;
        pfid = lfsck_dto2fid(parent);
 
-       /* Hold update lock on the parent to prevent others to access. */
-       rc = lfsck_ibits_lock(env, lfsck, parent, &plh,
-                             MDS_INODELOCK_UPDATE, LCK_EX);
-       if (rc != 0)
-               GOTO(log, rc);
-
+again:
        do {
                namelen = snprintf(info->lti_key, NAME_MAX, DFID"%s-%s-%d",
                                   PFID(cfid), infix, type, idx++);
-               rc = dt_lookup(env, parent, (struct dt_rec *)tfid,
-                              (const struct dt_key *)info->lti_key,
-                              BYPASS_CAPA);
+               rc = dt_lookup(env, parent, (struct dt_rec *)&tfid,
+                              (const struct dt_key *)info->lti_key);
                if (rc != 0 && rc != -ENOENT)
                        GOTO(log, rc);
 
-               if (unlikely(rc == 0 && lu_fid_eq(cfid, tfid)))
+               if (unlikely(rc == 0 && lu_fid_eq(cfid, &tfid)))
                        exist = true;
        } while (rc == 0 && !exist);
 
+       rc = lfsck_lock(env, lfsck, parent, info->lti_key, pllh,
+                       MDS_INODELOCK_UPDATE, LCK_PW);
+       if (rc != 0)
+               GOTO(log, rc);
+
+       /* Re-check whether the name conflict with othrs after taken
+        * the ldlm lock. */
+       rc = dt_lookup(env, parent, (struct dt_rec *)&tfid,
+                      (const struct dt_key *)info->lti_key);
+       if (rc == 0) {
+               if (!lu_fid_eq(cfid, &tfid)) {
+                       exist = false;
+                       lfsck_unlock(pllh);
+                       goto again;
+               }
+
+               exist = true;
+       } else if (rc != -ENOENT) {
+               GOTO(log, rc);
+       } else {
+               exist = false;
+       }
+
        cname->ln_name = info->lti_key;
        cname->ln_namelen = namelen;
        rc = linkea_data_new(&ldata, &info->lti_linkea_buf2);
@@ -851,8 +977,8 @@ static int lfsck_namespace_insert_orphan(const struct lu_env *env,
                GOTO(log, rc);
 
        rc = lfsck_ibits_lock(env, lfsck, orphan, &clh,
-                             MDS_INODELOCK_UPDATE | MDS_INODELOCK_LOOKUP,
-                             LCK_EX);
+                             MDS_INODELOCK_UPDATE | MDS_INODELOCK_LOOKUP |
+                             MDS_INODELOCK_XATTR, LCK_EX);
        if (rc != 0)
                GOTO(log, rc);
 
@@ -917,22 +1043,20 @@ static int lfsck_namespace_insert_orphan(const struct lu_env *env,
 
                if (S_ISDIR(lfsck_object_type(orphan))) {
                        rc = dt_delete(env, orphan,
-                                      (const struct dt_key *)dotdot, th,
-                                      BYPASS_CAPA);
+                                      (const struct dt_key *)dotdot, th);
                        if (rc != 0)
                                GOTO(unlock, rc);
 
                        rec->rec_type = S_IFDIR;
                        rec->rec_fid = pfid;
                        rc = dt_insert(env, orphan, (const struct dt_rec *)rec,
-                                      (const struct dt_key *)dotdot, th,
-                                      BYPASS_CAPA, 1);
+                                      (const struct dt_key *)dotdot, th, 1);
                        if (rc != 0)
                                GOTO(unlock, rc);
                }
 
                rc = dt_xattr_set(env, orphan, &linkea_buf, XATTR_NAME_LINK, 0,
-                                 th, BYPASS_CAPA);
+                                 th);
        } else {
                if (rc == 0 && count != NULL)
                        *count = ldata.ld_leh->leh_reccount;
@@ -945,8 +1069,7 @@ static int lfsck_namespace_insert_orphan(const struct lu_env *env,
                rec->rec_type = lfsck_object_type(orphan) & S_IFMT;
                rec->rec_fid = cfid;
                rc = dt_insert(env, parent, (const struct dt_rec *)rec,
-                              (const struct dt_key *)cname->ln_name,
-                              th, BYPASS_CAPA, 1);
+                              (const struct dt_key *)cname->ln_name, th, 1);
                if (rc == 0 && S_ISDIR(rec->rec_type)) {
                        dt_write_lock(env, parent, 0);
                        rc = dt_ref_add(env, parent, th);
@@ -954,10 +1077,8 @@ static int lfsck_namespace_insert_orphan(const struct lu_env *env,
                }
        }
 
-       if (rc != 0)
-               GOTO(unlock, rc);
-
-       rc = dt_attr_set(env, orphan, la, th, BYPASS_CAPA);
+       if (rc == 0)
+               rc = dt_attr_set(env, orphan, la, th);
 
        GOTO(stop, rc = (rc == 0 ? 1 : rc));
 
@@ -969,7 +1090,7 @@ stop:
 
 log:
        lfsck_ibits_unlock(&clh, LCK_EX);
-       lfsck_ibits_unlock(&plh, LCK_EX);
+       lfsck_unlock(pllh);
        CDEBUG(D_LFSCK, "%s: namespace LFSCK insert orphan for the "
               "object "DFID", name = %s: rc = %d\n",
               lfsck_lfsck2name(lfsck), PFID(cfid),
@@ -1016,21 +1137,34 @@ static int lfsck_namespace_insert_normal(const struct lu_env *env,
        struct lu_attr                  *la     = &info->lti_la;
        struct dt_insert_rec            *rec    = &info->lti_dt_rec;
        struct lfsck_instance           *lfsck  = com->lc_lfsck;
+       /* The child and its name may be on different MDTs. */
        struct dt_device                *dev    = lfsck->li_next;
+       struct dt_object                *pobj   = NULL;
+       struct dt_object                *cobj   = NULL;
        struct thandle                  *th     = NULL;
-       struct lustre_handle             lh     = { 0 };
+       struct lfsck_lock_handle        *llh    = &info->lti_llh;
        int                              rc     = 0;
        ENTRY;
 
-       if (unlikely(!dt_try_as_dir(env, parent)))
+       /* @parent/@child may be based on lfsck->li_bottom,
+        * but here we need the object based on the lfsck->li_next. */
+
+       pobj = lfsck_object_locate(dev, parent);
+       if (IS_ERR(pobj))
+               GOTO(log, rc = PTR_ERR(pobj));
+
+       if (unlikely(!dt_try_as_dir(env, pobj)))
                GOTO(log, rc = -ENOTDIR);
 
+       cobj = lfsck_object_locate(dev, child);
+       if (IS_ERR(cobj))
+               GOTO(log, rc = PTR_ERR(cobj));
+
        if (lfsck->li_bookmark_ram.lb_param & LPF_DRYRUN)
                GOTO(log, rc = 1);
 
-       /* Hold update lock on the parent to prevent others to access. */
-       rc = lfsck_ibits_lock(env, lfsck, parent, &lh,
-                             MDS_INODELOCK_UPDATE, LCK_EX);
+       rc = lfsck_lock(env, lfsck, parent, name, llh,
+                       MDS_INODELOCK_UPDATE, LCK_PW);
        if (rc != 0)
                GOTO(log, rc);
 
@@ -1038,15 +1172,15 @@ static int lfsck_namespace_insert_normal(const struct lu_env *env,
        if (IS_ERR(th))
                GOTO(unlock, rc = PTR_ERR(th));
 
-       rec->rec_type = lfsck_object_type(child) & S_IFMT;
-       rec->rec_fid = lfsck_dto2fid(child);
-       rc = dt_declare_insert(env, parent, (const struct dt_rec *)rec,
+       rec->rec_type = lfsck_object_type(cobj) & S_IFMT;
+       rec->rec_fid = lfsck_dto2fid(cobj);
+       rc = dt_declare_insert(env, pobj, (const struct dt_rec *)rec,
                               (const struct dt_key *)name, th);
        if (rc != 0)
                GOTO(stop, rc);
 
        if (S_ISDIR(rec->rec_type)) {
-               rc = dt_declare_ref_add(env, parent, th);
+               rc = dt_declare_ref_add(env, pobj, th);
                if (rc != 0)
                        GOTO(stop, rc);
        }
@@ -1054,11 +1188,11 @@ static int lfsck_namespace_insert_normal(const struct lu_env *env,
        memset(la, 0, sizeof(*la));
        la->la_ctime = cfs_time_current_sec();
        la->la_valid = LA_CTIME;
-       rc = dt_declare_attr_set(env, parent, la, th);
+       rc = dt_declare_attr_set(env, pobj, la, th);
        if (rc != 0)
                GOTO(stop, rc);
 
-       rc = dt_declare_attr_set(env, child, la, th);
+       rc = dt_declare_attr_set(env, cobj, la, th);
        if (rc != 0)
                GOTO(stop, rc);
 
@@ -1066,25 +1200,25 @@ static int lfsck_namespace_insert_normal(const struct lu_env *env,
        if (rc != 0)
                GOTO(stop, rc);
 
-       rc = dt_insert(env, parent, (const struct dt_rec *)rec,
-                      (const struct dt_key *)name, th, BYPASS_CAPA, 1);
+       rc = dt_insert(env, pobj, (const struct dt_rec *)rec,
+                      (const struct dt_key *)name, th, 1);
        if (rc != 0)
                GOTO(stop, rc);
 
        if (S_ISDIR(rec->rec_type)) {
-               dt_write_lock(env, parent, 0);
-               rc = dt_ref_add(env, parent, th);
-               dt_write_unlock(env, parent);
+               dt_write_lock(env, pobj, 0);
+               rc = dt_ref_add(env, pobj, th);
+               dt_write_unlock(env, pobj);
                if (rc != 0)
                        GOTO(stop, rc);
        }
 
        la->la_ctime = cfs_time_current_sec();
-       rc = dt_attr_set(env, parent, la, th, BYPASS_CAPA);
+       rc = dt_attr_set(env, pobj, la, th);
        if (rc != 0)
                GOTO(stop, rc);
 
-       rc = dt_attr_set(env, child, la, th, BYPASS_CAPA);
+       rc = dt_attr_set(env, cobj, la, th);
 
        GOTO(stop, rc = (rc == 0 ? 1 : rc));
 
@@ -1092,7 +1226,7 @@ stop:
        dt_trans_stop(env, dev, th);
 
 unlock:
-       lfsck_ibits_unlock(&lh, LCK_EX);
+       lfsck_unlock(llh);
 
 log:
        CDEBUG(D_LFSCK, "%s: namespace LFSCK insert object "DFID" with "
@@ -1113,116 +1247,7 @@ log:
 }
 
 /**
- * Create the specified orphan MDT-object on remote MDT.
- *
- * The LFSCK instance on this MDT will send LFSCK RPC to remote MDT to
- * ask the remote LFSCK instance to create the specified orphan object
- * under .lustre/lost+found/MDTxxxx/ directory with the name:
- * ${FID}-P-${conflict_version}.
- *
- * \param[in] env      pointer to the thread context
- * \param[in] com      pointer to the lfsck component
- * \param[in] orphan   pointer to the orphan MDT-object
- * \param[in] type     the orphan's type to be created
- *
- *  type "P":          The orphan object to be created was a parent directory
- *                     of some MDT-object which linkEA shows that the @orphan
- *                     object is missing.
- *
- * \see lfsck_layout_recreate_parent() for more types.
- *
- * \param[in] lmv      pointer to master LMV EA that will be set to the orphan
- *
- * \retval             positive number for repaired cases
- * \retval             0 if needs to repair nothing
- * \retval             negative error number on failure
- */
-static int lfsck_namespace_create_orphan_remote(const struct lu_env *env,
-                                               struct lfsck_component *com,
-                                               struct dt_object *orphan,
-                                               __u32 type,
-                                               struct lmv_mds_md_v1 *lmv)
-{
-       struct lfsck_thread_info        *info   = lfsck_env_info(env);
-       struct lfsck_request            *lr     = &info->lti_lr;
-       struct lu_seq_range             *range  = &info->lti_range;
-       const struct lu_fid             *fid    = lfsck_dto2fid(orphan);
-       struct lfsck_namespace          *ns     = com->lc_file_ram;
-       struct lfsck_instance           *lfsck  = com->lc_lfsck;
-       struct seq_server_site          *ss     =
-                       lu_site2seq(lfsck->li_bottom->dd_lu_dev.ld_site);
-       struct lfsck_tgt_desc           *ltd    = NULL;
-       struct ptlrpc_request           *req    = NULL;
-       int                              rc;
-       ENTRY;
-
-       if (lfsck->li_bookmark_ram.lb_param & LPF_DRYRUN)
-               GOTO(out, rc = 1);
-
-       fld_range_set_mdt(range);
-       rc = fld_server_lookup(env, ss->ss_server_fld, fid_seq(fid), range);
-       if (rc != 0)
-               GOTO(out, rc);
-
-       ltd = lfsck_tgt_get(&lfsck->li_mdt_descs, range->lsr_index);
-       if (ltd == NULL) {
-               ns->ln_flags |= LF_INCOMPLETE;
-
-               GOTO(out, rc = -ENODEV);
-       }
-
-       req = ptlrpc_request_alloc(class_exp2cliimp(ltd->ltd_exp),
-                                  &RQF_LFSCK_NOTIFY);
-       if (req == NULL)
-               GOTO(out, rc = -ENOMEM);
-
-       rc = ptlrpc_request_pack(req, LUSTRE_OBD_VERSION, LFSCK_NOTIFY);
-       if (rc != 0) {
-               ptlrpc_request_free(req);
-
-               GOTO(out, rc);
-       }
-
-       lr = req_capsule_client_get(&req->rq_pill, &RMF_LFSCK_REQUEST);
-       memset(lr, 0, sizeof(*lr));
-       lr->lr_event = LE_CREATE_ORPHAN;
-       lr->lr_index = lfsck_dev_idx(lfsck->li_bottom);
-       lr->lr_active = LFSCK_TYPE_NAMESPACE;
-       lr->lr_fid = *fid;
-       lr->lr_type = type;
-       if (lmv != NULL) {
-               lr->lr_hash_type = lmv->lmv_hash_type;
-               lr->lr_stripe_count = lmv->lmv_stripe_count;
-               lr->lr_layout_version = lmv->lmv_layout_version;
-               memcpy(lr->lr_pool_name, lmv->lmv_pool_name,
-                      sizeof(lr->lr_pool_name));
-       }
-
-       ptlrpc_request_set_replen(req);
-       rc = ptlrpc_queue_wait(req);
-       ptlrpc_req_finished(req);
-
-       if (rc == 0)
-               rc = 1;
-       else if (rc == -EEXIST)
-               rc = 0;
-
-       GOTO(out, rc);
-
-out:
-       CDEBUG(D_LFSCK, "%s: namespace LFSCK create object "
-              DFID" on the MDT %x remotely: rc = %d\n",
-              lfsck_lfsck2name(lfsck), PFID(fid),
-              ltd != NULL ? ltd->ltd_index : -1, rc);
-
-       if (ltd != NULL)
-               lfsck_tgt_put(ltd);
-
-       return rc;
-}
-
-/**
- * Create the specified orphan MDT-object locally.
+ * Create the specified orphan directory.
  *
  * For the case that the parent MDT-object stored in some MDT-object's
  * linkEA entry is lost, the LFSCK will re-create the parent object as
@@ -1232,24 +1257,15 @@ out:
  * \param[in] env      pointer to the thread context
  * \param[in] com      pointer to the lfsck component
  * \param[in] orphan   pointer to the orphan MDT-object to be created
- * \param[in] type     the orphan's type to be created
- *
- *  type "P":          The orphan object to be created was a parent directory
- *                     of some MDT-object which linkEA shows that the @orphan
- *                     object is missing.
- *
- * \see lfsck_layout_recreate_parent() for more types.
- *
  * \param[in] lmv      pointer to master LMV EA that will be set to the orphan
  *
  * \retval             positive number for repaired cases
  * \retval             negative error number on failure
  */
-static int lfsck_namespace_create_orphan_local(const struct lu_env *env,
-                                              struct lfsck_component *com,
-                                              struct dt_object *orphan,
-                                              __u32 type,
-                                              struct lmv_mds_md_v1 *lmv)
+static int lfsck_namespace_create_orphan_dir(const struct lu_env *env,
+                                            struct lfsck_component *com,
+                                            struct dt_object *orphan,
+                                            struct lmv_mds_md_v1 *lmv)
 {
        struct lfsck_thread_info        *info   = lfsck_env_info(env);
        struct lu_attr                  *la     = &info->lti_la;
@@ -1257,17 +1273,16 @@ static int lfsck_namespace_create_orphan_local(const struct lu_env *env,
        struct dt_object_format         *dof    = &info->lti_dof;
        struct lu_name                  *cname  = &info->lti_name2;
        struct dt_insert_rec            *rec    = &info->lti_dt_rec;
-       struct lu_fid                   *tfid   = &info->lti_fid;
        struct lmv_mds_md_v1            *lmv2   = &info->lti_lmv2;
        const struct lu_fid             *cfid   = lfsck_dto2fid(orphan);
-       const struct lu_fid             *pfid;
+       struct lu_fid                    tfid;
        struct lfsck_instance           *lfsck  = com->lc_lfsck;
-       struct dt_device                *dev    = lfsck->li_bottom;
+       struct lfsck_namespace          *ns     = com->lc_file_ram;
+       struct dt_device                *dev    = lfsck_obj2dev(orphan);
        struct dt_object                *parent = NULL;
-       struct dt_object                *child  = NULL;
        struct thandle                  *th     = NULL;
-       struct lustre_handle             lh     = { 0 };
-       struct linkea_data               ldata  = { 0 };
+       struct lfsck_lock_handle        *llh    = &info->lti_llh;
+       struct linkea_data               ldata  = { NULL };
        struct lu_buf                    linkea_buf;
        struct lu_buf                    lmv_buf;
        char                             name[32];
@@ -1277,61 +1292,90 @@ static int lfsck_namespace_create_orphan_local(const struct lu_env *env,
        ENTRY;
 
        LASSERT(!dt_object_exists(orphan));
-       LASSERT(!dt_object_remote(orphan));
-
-       /* @orphan maybe not attached to lfsck->li_bottom */
-       child = lfsck_object_find_by_dev(env, dev, cfid);
-       if (IS_ERR(child))
-               GOTO(log, rc = PTR_ERR(child));
 
        cname->ln_name = NULL;
        if (lfsck->li_bookmark_ram.lb_param & LPF_DRYRUN)
                GOTO(log, rc = 1);
 
-       /* Create .lustre/lost+found/MDTxxxx when needed. */
-       if (unlikely(lfsck->li_lpf_obj == NULL)) {
-               rc = lfsck_create_lpf(env, lfsck);
+       if (dt_object_remote(orphan)) {
+               LASSERT(lfsck->li_lpf_root_obj != NULL);
+
+               idx = lfsck_find_mdt_idx_by_fid(env, lfsck, cfid);
+               if (idx < 0)
+                       GOTO(log, rc = idx);
+
+               snprintf(name, 8, "MDT%04x", idx);
+               rc = dt_lookup(env, lfsck->li_lpf_root_obj,
+                              (struct dt_rec *)&tfid,
+                              (const struct dt_key *)name);
                if (rc != 0)
-                       GOTO(log, rc);
+                       GOTO(log, rc = (rc == -ENOENT ? -ENXIO : rc));
+
+               parent = lfsck_object_find_bottom(env, lfsck, &tfid);
+               if (IS_ERR(parent))
+                       GOTO(log, rc = PTR_ERR(parent));
+
+               if (unlikely(!dt_try_as_dir(env, parent)))
+                       GOTO(log, rc = -ENOTDIR);
+       } else {
+               if (unlikely(lfsck->li_lpf_obj == NULL))
+                       GOTO(log, rc = -ENXIO);
+
+               parent = lfsck->li_lpf_obj;
        }
 
-       parent = lfsck->li_lpf_obj;
-       pfid = lfsck_dto2fid(parent);
+       dev = lfsck_find_dev_by_fid(env, lfsck, cfid);
+       if (IS_ERR(dev))
+               GOTO(log, rc = PTR_ERR(dev));
 
-       /* Hold update lock on the parent to prevent others to access. */
-       rc = lfsck_ibits_lock(env, lfsck, parent, &lh,
-                             MDS_INODELOCK_UPDATE, LCK_EX);
-       if (rc != 0)
-               GOTO(log, rc);
+       idx = 0;
 
+again:
        do {
                namelen = snprintf(name, 31, DFID"-P-%d",
                                   PFID(cfid), idx++);
-               rc = dt_lookup(env, parent, (struct dt_rec *)tfid,
-                              (const struct dt_key *)name, BYPASS_CAPA);
+               rc = dt_lookup(env, parent, (struct dt_rec *)&tfid,
+                              (const struct dt_key *)name);
                if (rc != 0 && rc != -ENOENT)
-                       GOTO(unlock1, rc);
+                       GOTO(log, rc);
        } while (rc == 0);
 
+       rc = lfsck_lock(env, lfsck, parent, name, llh,
+                       MDS_INODELOCK_UPDATE, LCK_PW);
+       if (rc != 0)
+               GOTO(log, rc);
+
+       /* Re-check whether the name conflict with othrs after taken
+        * the ldlm lock. */
+       rc = dt_lookup(env, parent, (struct dt_rec *)&tfid,
+                      (const struct dt_key *)name);
+       if (unlikely(rc == 0)) {
+               lfsck_unlock(llh);
+               goto again;
+       }
+
+       if (rc != -ENOENT)
+               GOTO(unlock1, rc);
+
        cname->ln_name = name;
        cname->ln_namelen = namelen;
 
        memset(la, 0, sizeof(*la));
-       la->la_mode = type | (S_ISDIR(type) ? 0700 : 0600);
+       la->la_mode = S_IFDIR | 0700;
        la->la_valid = LA_TYPE | LA_MODE | LA_UID | LA_GID |
                       LA_ATIME | LA_MTIME | LA_CTIME;
 
-       child->do_ops->do_ah_init(env, hint, parent, child,
-                                 la->la_mode & S_IFMT);
+       orphan->do_ops->do_ah_init(env, hint, parent, orphan,
+                                  la->la_mode & S_IFMT);
 
        memset(dof, 0, sizeof(*dof));
-       dof->dof_type = dt_mode_to_dft(type);
+       dof->dof_type = dt_mode_to_dft(S_IFDIR);
 
        rc = linkea_data_new(&ldata, &info->lti_linkea_buf2);
        if (rc != 0)
                GOTO(unlock1, rc);
 
-       rc = linkea_add_buf(&ldata, cname, pfid);
+       rc = linkea_add_buf(&ldata, cname, lfsck_dto2fid(parent));
        if (rc != 0)
                GOTO(unlock1, rc);
 
@@ -1339,19 +1383,44 @@ static int lfsck_namespace_create_orphan_local(const struct lu_env *env,
        if (IS_ERR(th))
                GOTO(unlock1, rc = PTR_ERR(th));
 
-       rc = dt_declare_create(env, child, la, hint, dof, th);
-       if (rc == 0 && S_ISDIR(type))
-               rc = dt_declare_ref_add(env, child, th);
+       /* Sync the remote transaction to guarantee that the subsequent
+        * lock against the @orphan can find the @orphan in time. */
+       if (dt_object_remote(orphan))
+               th->th_sync = 1;
 
+       rc = dt_declare_create(env, orphan, la, hint, dof, th);
+       if (rc != 0)
+               GOTO(stop, rc);
+
+       if (unlikely(!dt_try_as_dir(env, orphan)))
+               GOTO(stop, rc = -ENOTDIR);
+
+       rec->rec_type = S_IFDIR;
+       rec->rec_fid = cfid;
+       rc = dt_declare_insert(env, orphan, (const struct dt_rec *)rec,
+                              (const struct dt_key *)dot, th);
+       if (rc != 0)
+               GOTO(stop, rc);
+
+       rec->rec_fid = lfsck_dto2fid(parent);
+       rc = dt_declare_insert(env, orphan, (const struct dt_rec *)rec,
+                              (const struct dt_key *)dotdot, th);
+       if (rc == 0)
+               rc = dt_declare_ref_add(env, orphan, th);
+
+       if (rc != 0)
+               GOTO(stop, rc);
+
+       rc = dt_declare_ref_add(env, orphan, th);
        if (rc != 0)
                GOTO(stop, rc);
 
        if (lmv != NULL) {
                lmv->lmv_magic = LMV_MAGIC;
-               lmv->lmv_master_mdt_index = lfsck_dev_idx(dev);
+               lmv->lmv_master_mdt_index = lfsck_dev_idx(lfsck);
                lfsck_lmv_header_cpu_to_le(lmv2, lmv);
                lfsck_buf_init(&lmv_buf, lmv2, sizeof(*lmv2));
-               rc = dt_declare_xattr_set(env, child, &lmv_buf,
+               rc = dt_declare_xattr_set(env, orphan, &lmv_buf,
                                          XATTR_NAME_LMV, 0, th);
                if (rc != 0)
                        GOTO(stop, rc);
@@ -1359,16 +1428,15 @@ static int lfsck_namespace_create_orphan_local(const struct lu_env *env,
 
        lfsck_buf_init(&linkea_buf, ldata.ld_buf->lb_buf,
                       ldata.ld_leh->leh_len);
-       rc = dt_declare_xattr_set(env, child, &linkea_buf,
+       rc = dt_declare_xattr_set(env, orphan, &linkea_buf,
                                  XATTR_NAME_LINK, 0, th);
        if (rc != 0)
                GOTO(stop, rc);
 
-       rec->rec_type = type;
        rec->rec_fid = cfid;
        rc = dt_declare_insert(env, parent, (const struct dt_rec *)rec,
                               (const struct dt_key *)name, th);
-       if (rc == 0 && S_ISDIR(type))
+       if (rc == 0)
                rc = dt_declare_ref_add(env, parent, th);
 
        if (rc != 0)
@@ -1378,52 +1446,43 @@ static int lfsck_namespace_create_orphan_local(const struct lu_env *env,
        if (rc != 0)
                GOTO(stop, rc);
 
-       dt_write_lock(env, child, 0);
-       rc = dt_create(env, child, la, hint, dof, th);
+       dt_write_lock(env, orphan, 0);
+       rc = dt_create(env, orphan, la, hint, dof, th);
        if (rc != 0)
                GOTO(unlock2, rc);
 
-       if (S_ISDIR(type)) {
-               if (unlikely(!dt_try_as_dir(env, child)))
-                       GOTO(unlock2, rc = -ENOTDIR);
-
-               rec->rec_type = S_IFDIR;
-               rec->rec_fid = cfid;
-               rc = dt_insert(env, child, (const struct dt_rec *)rec,
-                              (const struct dt_key *)dot, th, BYPASS_CAPA, 1);
-               if (rc != 0)
-                       GOTO(unlock2, rc);
+       rec->rec_fid = cfid;
+       rc = dt_insert(env, orphan, (const struct dt_rec *)rec,
+                      (const struct dt_key *)dot, th, 1);
+       if (rc != 0)
+               GOTO(unlock2, rc);
 
-               rec->rec_fid = pfid;
-               rc = dt_insert(env, child, (const struct dt_rec *)rec,
-                              (const struct dt_key *)dotdot, th,
-                              BYPASS_CAPA, 1);
-               if (rc != 0)
-                       GOTO(unlock2, rc);
+       rec->rec_fid = lfsck_dto2fid(parent);
+       rc = dt_insert(env, orphan, (const struct dt_rec *)rec,
+                      (const struct dt_key *)dotdot, th, 1);
+       if (rc != 0)
+               GOTO(unlock2, rc);
 
-               rc = dt_ref_add(env, child, th);
-               if (rc != 0)
-                       GOTO(unlock2, rc);
-       }
+       rc = dt_ref_add(env, orphan, th);
+       if (rc != 0)
+               GOTO(unlock2, rc);
 
        if (lmv != NULL) {
-               rc = dt_xattr_set(env, child, &lmv_buf, XATTR_NAME_LMV, 0,
-                                 th, BYPASS_CAPA);
+               rc = dt_xattr_set(env, orphan, &lmv_buf, XATTR_NAME_LMV, 0, th);
                if (rc != 0)
                        GOTO(unlock2, rc);
        }
 
-       rc = dt_xattr_set(env, child, &linkea_buf,
-                         XATTR_NAME_LINK, 0, th, BYPASS_CAPA);
-       dt_write_unlock(env, child);
+       rc = dt_xattr_set(env, orphan, &linkea_buf,
+                         XATTR_NAME_LINK, 0, th);
+       dt_write_unlock(env, orphan);
        if (rc != 0)
                GOTO(stop, rc);
 
-       rec->rec_type = type;
        rec->rec_fid = cfid;
        rc = dt_insert(env, parent, (const struct dt_rec *)rec,
-                      (const struct dt_key *)name, th, BYPASS_CAPA, 1);
-       if (rc == 0 && S_ISDIR(type)) {
+                      (const struct dt_key *)name, th, 1);
+       if (rc == 0) {
                dt_write_lock(env, parent, 0);
                rc = dt_ref_add(env, parent, th);
                dt_write_unlock(env, parent);
@@ -1432,64 +1491,22 @@ static int lfsck_namespace_create_orphan_local(const struct lu_env *env,
        GOTO(stop, rc = (rc == 0 ? 1 : rc));
 
 unlock2:
-       dt_write_unlock(env, child);
+       dt_write_unlock(env, orphan);
 
 stop:
        dt_trans_stop(env, dev, th);
 
 unlock1:
-       lfsck_ibits_unlock(&lh, LCK_EX);
+       lfsck_unlock(llh);
 
 log:
-       CDEBUG(D_LFSCK, "%s: namespace LFSCK create orphan locally for "
-              "the object "DFID", name = %s, type %o: rc = %d\n",
+       CDEBUG(D_LFSCK, "%s: namespace LFSCK create orphan dir for "
+              "the object "DFID", name = %s: rc = %d\n",
               lfsck_lfsck2name(lfsck), PFID(cfid),
-              cname->ln_name != NULL ? cname->ln_name : "<NULL>", type, rc);
-
-       if (child != NULL && !IS_ERR(child))
-               lfsck_object_put(env, child);
-
-       return rc;
-}
-
-/**
- * Create the specified orphan MDT-object.
- *
- * For the case that the parent MDT-object stored in some MDT-object's
- * linkEA entry is lost, the LFSCK will re-create the parent object as
- * an orphan and insert it into .lustre/lost+found/MDTxxxx/ directory
- * with the name: ${FID}-P-${conflict_version}.
- *
- * \param[in] env      pointer to the thread context
- * \param[in] com      pointer to the lfsck component
- * \param[in] orphan   pointer to the orphan MDT-object
- *
- *  type "P":          The orphan object to be created was a parent directory
- *                     of some MDT-object which linkEA shows that the @orphan
- *                     object is missing.
- *
- * \see lfsck_layout_recreate_parent() for more types.
- *
- * \param[in] lmv      pointer to master LMV EA that will be set to the orphan
- *
- * \retval             positive number for repaired cases
- * \retval             0 if needs to repair nothing
- * \retval             negative error number on failure
- */
-static int lfsck_namespace_create_orphan(const struct lu_env *env,
-                                        struct lfsck_component *com,
-                                        struct dt_object *orphan,
-                                        struct lmv_mds_md_v1 *lmv)
-{
-       struct lfsck_namespace *ns = com->lc_file_ram;
-       int                     rc;
+              cname->ln_name != NULL ? cname->ln_name : "<NULL>", rc);
 
-       if (dt_object_remote(orphan))
-               rc = lfsck_namespace_create_orphan_remote(env, com, orphan,
-                                                         S_IFDIR, lmv);
-       else
-               rc = lfsck_namespace_create_orphan_local(env, com, orphan,
-                                                        S_IFDIR, lmv);
+       if (parent != NULL && !IS_ERR(parent) && parent != lfsck->li_lpf_obj)
+               lfsck_object_put(env, parent);
 
        if (rc != 0)
                ns->ln_flags |= LF_INCONSISTENT;
@@ -1526,18 +1543,18 @@ static int lfsck_namespace_shrink_linkea(const struct lu_env *env,
                                         bool next)
 {
        struct lfsck_instance           *lfsck     = com->lc_lfsck;
-       struct dt_device                *dev       = lfsck->li_bottom;
+       struct dt_device                *dev       = lfsck_obj2dev(obj);
        struct lfsck_bookmark           *bk        = &lfsck->li_bookmark_ram;
        struct thandle                  *th        = NULL;
        struct lustre_handle             lh        = { 0 };
-       struct linkea_data               ldata_new = { 0 };
+       struct linkea_data               ldata_new = { NULL };
        struct lu_buf                    linkea_buf;
        int                              rc        = 0;
        ENTRY;
 
        rc = lfsck_ibits_lock(env, lfsck, obj, &lh,
-                             MDS_INODELOCK_UPDATE |
-                             MDS_INODELOCK_XATTR, LCK_EX);
+                             MDS_INODELOCK_UPDATE | MDS_INODELOCK_XATTR,
+                             LCK_EX);
        if (rc != 0)
                GOTO(log, rc);
 
@@ -1595,8 +1612,7 @@ again:
 
        lfsck_buf_init(&linkea_buf, ldata_new.ld_buf->lb_buf,
                       ldata_new.ld_leh->leh_len);
-       rc = dt_xattr_set(env, obj, &linkea_buf,
-                         XATTR_NAME_LINK, 0, th, BYPASS_CAPA);
+       rc = dt_xattr_set(env, obj, &linkea_buf, XATTR_NAME_LINK, 0, th);
 
        GOTO(unlock2, rc = (rc == 0 ? 1 : rc));
 
@@ -1652,20 +1668,21 @@ static int lfsck_namespace_shrink_linkea_cond(const struct lu_env *env,
                                              struct lu_name *cname,
                                              struct lu_fid *pfid)
 {
-       struct lu_fid           *cfid   = &lfsck_env_info(env)->lti_fid3;
-       struct lustre_handle     lh     = { 0 };
-       int                      rc;
+       struct lfsck_thread_info *info  = lfsck_env_info(env);
+       struct lu_fid            *cfid  = &info->lti_fid3;
+       struct lfsck_lock_handle *llh   = &info->lti_llh;
+       int                       rc;
        ENTRY;
 
-       rc = lfsck_ibits_lock(env, com->lc_lfsck, parent, &lh,
-                             MDS_INODELOCK_UPDATE, LCK_EX);
+       rc = lfsck_lock(env, com->lc_lfsck, parent, cname->ln_name, llh,
+                       MDS_INODELOCK_UPDATE, LCK_PR);
        if (rc != 0)
                RETURN(rc);
 
        dt_read_lock(env, parent, 0);
        if (unlikely(lfsck_is_dead_obj(parent))) {
                dt_read_unlock(env, parent);
-               lfsck_ibits_unlock(&lh, LCK_EX);
+               lfsck_unlock(llh);
                rc = lfsck_namespace_shrink_linkea(env, com, child, ldata,
                                                   cname, pfid, true);
 
@@ -1673,8 +1690,7 @@ static int lfsck_namespace_shrink_linkea_cond(const struct lu_env *env,
        }
 
        rc = dt_lookup(env, parent, (struct dt_rec *)cfid,
-                      (const struct dt_key *)cname->ln_name,
-                      BYPASS_CAPA);
+                      (const struct dt_key *)cname->ln_name);
        dt_read_unlock(env, parent);
 
        /* It is safe to release the ldlm lock, because when the logic come
@@ -1684,7 +1700,7 @@ static int lfsck_namespace_shrink_linkea_cond(const struct lu_env *env,
         * has removed the specified linkEA entry by race, then it is OK,
         * because the subsequent lfsck_namespace_shrink_linkea() can handle
         * such case. */
-       lfsck_ibits_unlock(&lh, LCK_EX);
+       lfsck_unlock(llh);
        if (rc == -ENOENT) {
                rc = lfsck_namespace_shrink_linkea(env, com, child, ldata,
                                                   cname, pfid, true);
@@ -1739,23 +1755,35 @@ static int lfsck_namespace_replace_cond(const struct lu_env *env,
                                        const struct lu_name *cname)
 {
        struct lfsck_thread_info        *info   = lfsck_env_info(env);
-       struct lu_fid                   *tfid   = &info->lti_fid5;
        struct lu_attr                  *la     = &info->lti_la;
        struct dt_insert_rec            *rec    = &info->lti_dt_rec;
+       struct lu_fid                    tfid;
        struct lfsck_instance           *lfsck  = com->lc_lfsck;
+       /* The child and its name may be on different MDTs. */
        struct dt_device                *dev    = lfsck->li_next;
        const char                      *name   = cname->ln_name;
-       struct dt_object                *obj    = NULL;
-       struct lustre_handle             plh    = { 0 };
+       struct dt_object                *pobj   = NULL;
+       struct dt_object                *cobj   = NULL;
+       struct lfsck_lock_handle        *pllh   = &info->lti_llh;
        struct lustre_handle             clh    = { 0 };
-       struct linkea_data               ldata  = { 0 };
+       struct linkea_data               ldata  = { NULL };
        struct thandle                  *th     = NULL;
        bool                             exist  = true;
        int                              rc     = 0;
        ENTRY;
 
-       rc = lfsck_ibits_lock(env, lfsck, parent, &plh,
-                             MDS_INODELOCK_UPDATE, LCK_EX);
+       /* @parent/@child may be based on lfsck->li_bottom,
+        * but here we need the object based on the lfsck->li_next. */
+
+       pobj = lfsck_object_locate(dev, parent);
+       if (IS_ERR(pobj))
+               GOTO(log, rc = PTR_ERR(pobj));
+
+       if (unlikely(!dt_try_as_dir(env, pobj)))
+               GOTO(log, rc = -ENOTDIR);
+
+       rc = lfsck_lock(env, lfsck, parent, name, pllh,
+                       MDS_INODELOCK_UPDATE, LCK_PW);
        if (rc != 0)
                GOTO(log, rc);
 
@@ -1764,9 +1792,9 @@ static int lfsck_namespace_replace_cond(const struct lu_env *env,
                goto replace;
        }
 
-       obj = lfsck_object_find(env, lfsck, cfid);
-       if (IS_ERR(obj)) {
-               rc = PTR_ERR(obj);
+       cobj = lfsck_object_find_by_dev(env, dev, cfid);
+       if (IS_ERR(cobj)) {
+               rc = PTR_ERR(cobj);
                if (rc == -ENOENT) {
                        exist = false;
                        goto replace;
@@ -1775,13 +1803,13 @@ static int lfsck_namespace_replace_cond(const struct lu_env *env,
                GOTO(log, rc);
        }
 
-       if (!dt_object_exists(obj)) {
+       if (!dt_object_exists(cobj)) {
                exist = false;
                goto replace;
        }
 
-       rc = dt_lookup(env, parent, (struct dt_rec *)tfid,
-                      (const struct dt_key *)name, BYPASS_CAPA);
+       rc = dt_lookup(env, pobj, (struct dt_rec *)&tfid,
+                      (const struct dt_key *)name);
        if (rc == -ENOENT) {
                exist = false;
                goto replace;
@@ -1791,22 +1819,23 @@ static int lfsck_namespace_replace_cond(const struct lu_env *env,
                GOTO(log, rc);
 
        /* Someone changed the name entry, cannot replace it. */
-       if (!lu_fid_eq(cfid, tfid))
+       if (!lu_fid_eq(cfid, &tfid))
                GOTO(log, rc = 0);
 
        /* lock the object to be destroyed. */
-       rc = lfsck_ibits_lock(env, lfsck, obj, &clh,
+       rc = lfsck_ibits_lock(env, lfsck, cobj, &clh,
                              MDS_INODELOCK_UPDATE |
-                             MDS_INODELOCK_XATTR, LCK_EX);
+                             MDS_INODELOCK_UPDATE | MDS_INODELOCK_XATTR,
+                             LCK_EX);
        if (rc != 0)
                GOTO(log, rc);
 
-       if (unlikely(lfsck_is_dead_obj(obj))) {
+       if (unlikely(lfsck_is_dead_obj(cobj))) {
                exist = false;
                goto replace;
        }
 
-       rc = dt_attr_get(env, obj, la, BYPASS_CAPA);
+       rc = dt_attr_get(env, cobj, la);
        if (rc != 0)
                GOTO(log, rc);
 
@@ -1816,8 +1845,7 @@ static int lfsck_namespace_replace_cond(const struct lu_env *env,
                GOTO(log, rc);
 
        if (S_ISREG(la->la_mode)) {
-               rc = dt_xattr_get(env, obj, &LU_BUF_NULL, XATTR_NAME_LOV,
-                                 BYPASS_CAPA);
+               rc = dt_xattr_get(env, cobj, &LU_BUF_NULL, XATTR_NAME_LOV);
                /* If someone has created related OST-object(s),
                 * then keep it. */
                if ((rc > 0) || (rc < 0 && rc != -ENODATA))
@@ -1836,7 +1864,7 @@ replace:
        if (rc != 0)
                GOTO(log, rc);
 
-       rc = linkea_links_find(&ldata, cname, lfsck_dto2fid(parent));
+       rc = linkea_links_find(&ldata, cname, lfsck_dto2fid(pobj));
        /* Someone moved the child, no need to replace. */
        if (rc != 0)
                GOTO(log, rc = 0);
@@ -1849,38 +1877,39 @@ replace:
                GOTO(log, rc = PTR_ERR(th));
 
        if (exist) {
-               rc = dt_declare_destroy(env, obj, th);
+               rc = dt_declare_destroy(env, cobj, th);
                if (rc != 0)
                        GOTO(stop, rc);
        }
 
-       rc = dt_declare_delete(env, parent, (const struct dt_key *)name, th);
+       rc = dt_declare_delete(env, pobj, (const struct dt_key *)name, th);
        if (rc != 0)
                GOTO(stop, rc);
 
        rec->rec_type = S_IFDIR;
        rec->rec_fid = lfsck_dto2fid(child);
-       rc = dt_declare_insert(env, parent, (const struct dt_rec *)rec,
+       rc = dt_declare_insert(env, pobj, (const struct dt_rec *)rec,
                               (const struct dt_key *)name, th);
        if (rc != 0)
                GOTO(stop, rc);
 
-       rc = dt_trans_start(env, dev, th);
+       rc = dt_trans_start_local(env, dev, th);
        if (rc != 0)
                GOTO(stop, rc);
 
        if (exist) {
-               rc = dt_destroy(env, obj, th);
+               rc = dt_destroy(env, cobj, th);
                if (rc != 0)
                        GOTO(stop, rc);
        }
 
        /* The old name entry maybe not exist. */
-       dt_delete(env, parent, (const struct dt_key *)name, th,
-                 BYPASS_CAPA);
+       rc = dt_delete(env, pobj, (const struct dt_key *)name, th);
+       if (rc != 0 && rc != -ENOENT)
+               GOTO(stop, rc);
 
-       rc = dt_insert(env, parent, (const struct dt_rec *)rec,
-                      (const struct dt_key *)name, th, BYPASS_CAPA, 1);
+       rc = dt_insert(env, pobj, (const struct dt_rec *)rec,
+                      (const struct dt_key *)name, th, 1);
 
        GOTO(stop, rc = (rc == 0 ? 1 : rc));
 
@@ -1889,9 +1918,10 @@ stop:
 
 log:
        lfsck_ibits_unlock(&clh, LCK_EX);
-       lfsck_ibits_unlock(&plh, LCK_EX);
-       if (obj != NULL && !IS_ERR(obj))
-               lfsck_object_put(env, obj);
+       lfsck_unlock(pllh);
+
+       if (cobj != NULL && !IS_ERR(cobj))
+               lfsck_object_put(env, cobj);
 
        CDEBUG(D_LFSCK, "%s: namespace LFSCK conditionally destroy the "
               "object "DFID" because of conflict with the object "DFID
@@ -1923,14 +1953,12 @@ int lfsck_namespace_rebuild_linkea(const struct lu_env *env,
                                   struct linkea_data *ldata)
 {
        struct lfsck_instance           *lfsck  = com->lc_lfsck;
-       struct dt_device                *dev    = lfsck->li_bottom;
+       struct dt_device                *dev    = lfsck_obj2dev(obj);
        struct thandle                  *th     = NULL;
        struct lu_buf                    linkea_buf;
        int                              rc     = 0;
        ENTRY;
 
-       LASSERT(!dt_object_remote(obj));
-
        th = dt_trans_create(env, dev);
        if (IS_ERR(th))
                GOTO(log, rc = PTR_ERR(th));
@@ -1954,7 +1982,7 @@ int lfsck_namespace_rebuild_linkea(const struct lu_env *env,
                GOTO(unlock, rc = 1);
 
        rc = dt_xattr_set(env, obj, &linkea_buf,
-                         XATTR_NAME_LINK, 0, th, BYPASS_CAPA);
+                         XATTR_NAME_LINK, 0, th);
 
        GOTO(unlock, rc = (rc == 0 ? 1 : rc));
 
@@ -2009,10 +2037,12 @@ int lfsck_namespace_repair_dirent(const struct lu_env *env,
        struct lfsck_thread_info        *info   = lfsck_env_info(env);
        struct dt_insert_rec            *rec    = &info->lti_dt_rec;
        const struct lu_fid             *cfid   = lfsck_dto2fid(child);
-       struct lu_fid                   *tfid   = &info->lti_fid5;
+       struct lu_fid                    tfid;
        struct lfsck_instance           *lfsck  = com->lc_lfsck;
+       struct dt_object                *dto;
        struct dt_device                *dev    = lfsck->li_next;
        struct thandle                  *th     = NULL;
+       struct lfsck_lock_handle        *llh    = &info->lti_llh;
        struct lustre_handle             lh     = { 0 };
        int                              rc     = 0;
        ENTRY;
@@ -2020,8 +2050,12 @@ int lfsck_namespace_repair_dirent(const struct lu_env *env,
        if (unlikely(!dt_try_as_dir(env, parent)))
                GOTO(log, rc = -ENOTDIR);
 
-       rc = lfsck_ibits_lock(env, lfsck, parent, &lh,
-                             MDS_INODELOCK_UPDATE, LCK_EX);
+       if (!update || strcmp(name, name2) == 0)
+               rc = lfsck_lock(env, lfsck, parent, name, llh,
+                               MDS_INODELOCK_UPDATE, LCK_PW);
+       else
+               rc = lfsck_ibits_lock(env, lfsck, parent, &lh,
+                                     MDS_INODELOCK_UPDATE, LCK_PW);
        if (rc != 0)
                GOTO(log, rc);
 
@@ -2029,14 +2063,15 @@ int lfsck_namespace_repair_dirent(const struct lu_env *env,
        if (IS_ERR(th))
                GOTO(unlock1, rc = PTR_ERR(th));
 
-       rc = dt_declare_delete(env, parent, (const struct dt_key *)name, th);
+       dto = dt_object_locate(parent, th->th_dev);
+       rc = dt_declare_delete(env, dto, (const struct dt_key *)name, th);
        if (rc != 0)
                GOTO(stop, rc);
 
        if (update) {
                rec->rec_type = lfsck_object_type(child) & S_IFMT;
                rec->rec_fid = cfid;
-               rc = dt_declare_insert(env, parent,
+               rc = dt_declare_insert(env, dto,
                                       (const struct dt_rec *)rec,
                                       (const struct dt_key *)name2, th);
                if (rc != 0)
@@ -2044,18 +2079,19 @@ int lfsck_namespace_repair_dirent(const struct lu_env *env,
        }
 
        if (dec) {
-               rc = dt_declare_ref_del(env, parent, th);
+               rc = dt_declare_ref_del(env, dto, th);
                if (rc != 0)
                        GOTO(stop, rc);
        }
 
-       rc = dt_trans_start(env, dev, th);
+       rc = dt_trans_start_local(env, dev, th);
        if (rc != 0)
                GOTO(stop, rc);
 
-       dt_write_lock(env, parent, 0);
-       rc = dt_lookup(env, parent, (struct dt_rec *)tfid,
-                      (const struct dt_key *)name, BYPASS_CAPA);
+
+       dt_write_lock(env, dto, 0);
+       rc = dt_lookup(env, dto, (struct dt_rec *)&tfid,
+                      (const struct dt_key *)name);
        /* Someone has removed the bad name entry by race. */
        if (rc == -ENOENT)
                GOTO(unlock2, rc = 0);
@@ -2065,28 +2101,26 @@ int lfsck_namespace_repair_dirent(const struct lu_env *env,
 
        /* Someone has removed the bad name entry and reused it for other
         * object by race. */
-       if (!lu_fid_eq(tfid, cfid))
+       if (!lu_fid_eq(&tfid, cfid))
                GOTO(unlock2, rc = 0);
 
        if (lfsck->li_bookmark_ram.lb_param & LPF_DRYRUN)
                GOTO(unlock2, rc = 1);
 
-       rc = dt_delete(env, parent, (const struct dt_key *)name, th,
-                      BYPASS_CAPA);
+       rc = dt_delete(env, dto, (const struct dt_key *)name, th);
        if (rc != 0)
                GOTO(unlock2, rc);
 
        if (update) {
-               rc = dt_insert(env, parent,
+               rc = dt_insert(env, dto,
                               (const struct dt_rec *)rec,
-                              (const struct dt_key *)name2, th,
-                              BYPASS_CAPA, 1);
+                              (const struct dt_key *)name2, th, 1);
                if (rc != 0)
                        GOTO(unlock2, rc);
        }
 
        if (dec) {
-               rc = dt_ref_del(env, parent, th);
+               rc = dt_ref_del(env, dto, th);
                if (rc != 0)
                        GOTO(unlock2, rc);
        }
@@ -2107,14 +2141,16 @@ stop:
                                             LNTF_CHECK_LINKEA, true);
 
 unlock1:
-       lfsck_ibits_unlock(&lh, LCK_EX);
+       /* It is harmless even if unlock the unused lock_handle */
+       lfsck_ibits_unlock(&lh, LCK_PW);
+       lfsck_unlock(llh);
 
 log:
        CDEBUG(D_LFSCK, "%s: namespace LFSCK assistant found bad name "
               "entry for: parent "DFID", child "DFID", name %s, type "
               "in name entry %o, type claimed by child %o. repair it "
               "by %s with new name2 %s: rc = %d\n", lfsck_lfsck2name(lfsck),
-              PFID(lfsck_dto2fid(parent)), PFID(lfsck_dto2fid(child)),
+              PFID(lfsck_dto2fid(parent)), PFID(cfid),
               name, type, update ? lfsck_object_type(child) : 0,
               update ? "updating" : "removing", name2, rc);
 
@@ -2154,9 +2190,9 @@ static int lfsck_namespace_repair_unmatched_pairs(const struct lu_env *env,
        struct lfsck_thread_info        *info   = lfsck_env_info(env);
        struct dt_insert_rec            *rec    = &info->lti_dt_rec;
        struct lfsck_instance           *lfsck  = com->lc_lfsck;
-       struct dt_device                *dev    = lfsck->li_bottom;
+       struct dt_device                *dev    = lfsck_obj2dev(obj);
        struct thandle                  *th     = NULL;
-       struct linkea_data               ldata  = { 0 };
+       struct linkea_data               ldata  = { NULL };
        struct lu_buf                    linkea_buf;
        int                              rc     = 0;
        ENTRY;
@@ -2207,16 +2243,15 @@ static int lfsck_namespace_repair_unmatched_pairs(const struct lu_env *env,
                GOTO(unlock, rc = 1);
 
        /* The old ".." name entry maybe not exist. */
-       dt_delete(env, obj, (const struct dt_key *)dotdot, th,
-                 BYPASS_CAPA);
+       dt_delete(env, obj, (const struct dt_key *)dotdot, th);
 
        rc = dt_insert(env, obj, (const struct dt_rec *)rec,
-                      (const struct dt_key *)dotdot, th, BYPASS_CAPA, 1);
+                      (const struct dt_key *)dotdot, th, 1);
        if (rc != 0)
                GOTO(unlock, rc);
 
        rc = dt_xattr_set(env, obj, &linkea_buf,
-                         XATTR_NAME_LINK, 0, th, BYPASS_CAPA);
+                         XATTR_NAME_LINK, 0, th);
 
        GOTO(unlock, rc = (rc == 0 ? 1 : rc));
 
@@ -2339,7 +2374,7 @@ lfsck_namespace_dsd_single(const struct lu_env *env,
        struct lfsck_thread_info *info          = lfsck_env_info(env);
        struct lu_name           *cname         = &info->lti_name;
        const struct lu_fid      *cfid          = lfsck_dto2fid(child);
-       struct lu_fid            *tfid          = &info->lti_fid3;
+       struct lu_fid             tfid;
        struct lfsck_namespace   *ns            = com->lc_file_ram;
        struct lfsck_instance    *lfsck         = com->lc_lfsck;
        struct dt_object         *parent        = NULL;
@@ -2347,9 +2382,9 @@ lfsck_namespace_dsd_single(const struct lu_env *env,
        int                       rc            = 0;
        ENTRY;
 
-       lfsck_namespace_unpack_linkea_entry(ldata, cname, tfid, info->lti_key);
+       lfsck_namespace_unpack_linkea_entry(ldata, cname, &tfid, info->lti_key);
        /* The unique linkEA entry with bad parent will be handled as orphan. */
-       if (!fid_is_sane(tfid)) {
+       if (!fid_is_sane(&tfid)) {
                if (!lustre_handle_is_used(lh) && retry != NULL)
                        *retry = true;
                else
@@ -2359,7 +2394,7 @@ lfsck_namespace_dsd_single(const struct lu_env *env,
                GOTO(out, rc);
        }
 
-       parent = lfsck_object_find_bottom(env, lfsck, tfid);
+       parent = lfsck_object_find_bottom(env, lfsck, &tfid);
        if (IS_ERR(parent))
                GOTO(out, rc = PTR_ERR(parent));
 
@@ -2401,7 +2436,7 @@ lost_parent:
                        /* It is an invalid name entry, we
                         * cannot trust the parent also. */
                        rc = lfsck_namespace_shrink_linkea(env, com, child,
-                                               ldata, cname, tfid, true);
+                                               ldata, cname, &tfid, true);
                        if (rc < 0)
                                GOTO(out, rc);
 
@@ -2414,7 +2449,7 @@ lost_parent:
                }
 
                /* Create the lost parent as an orphan. */
-               rc = lfsck_namespace_create_orphan(env, com, parent, lmv);
+               rc = lfsck_namespace_create_orphan_dir(env, com, parent, lmv);
                if (rc >= 0) {
                        /* Add the missing name entry to the parent. */
                        rc = lfsck_namespace_insert_normal(env, com, parent,
@@ -2430,7 +2465,7 @@ lost_parent:
                                 * current system to be consistent. */
                                rc = lfsck_namespace_shrink_linkea(env,
                                                com, child, ldata,
-                                               cname, tfid, true);
+                                               cname, &tfid, true);
                                if (rc >= 0) {
                                        snprintf(info->lti_tmpbuf,
                                                 sizeof(info->lti_tmpbuf),
@@ -2456,8 +2491,8 @@ lost_parent:
                GOTO(out, rc);
        }
 
-       rc = dt_lookup(env, parent, (struct dt_rec *)tfid,
-                      (const struct dt_key *)cname->ln_name, BYPASS_CAPA);
+       rc = dt_lookup(env, parent, (struct dt_rec *)&tfid,
+                      (const struct dt_key *)cname->ln_name);
        if (rc == -ENOENT) {
                /* If the LFSCK is marked as LF_INCOMPLETE, then means some MDT
                 * has ever tried to verify some remote MDT-object that resides
@@ -2486,7 +2521,7 @@ lost_parent:
                /* It is an invalid name entry, drop it. */
                if (unlikely(rc > 0)) {
                        rc = lfsck_namespace_shrink_linkea(env, com, child,
-                                               ldata, cname, tfid, true);
+                                               ldata, cname, &tfid, true);
                        if (rc >= 0) {
                                snprintf(info->lti_tmpbuf,
                                         sizeof(info->lti_tmpbuf),
@@ -2518,7 +2553,7 @@ lost_parent:
                         * internal status of create operation. Under such
                         * case, nothing to be done. */
                        rc = lfsck_namespace_shrink_linkea_cond(env, com,
-                                       parent, child, ldata, cname, tfid);
+                                       parent, child, ldata, cname, &tfid);
                        if (rc >= 0) {
                                snprintf(info->lti_tmpbuf,
                                         sizeof(info->lti_tmpbuf),
@@ -2534,7 +2569,7 @@ lost_parent:
        if (rc != 0)
                GOTO(out, rc);
 
-       if (!lu_fid_eq(tfid, cfid)) {
+       if (!lu_fid_eq(&tfid, cfid)) {
                if (!lustre_handle_is_used(lh) && retry != NULL) {
                        *retry = true;
 
@@ -2546,7 +2581,7 @@ lost_parent:
                 * may be created by the LFSCK for repairing dangling
                 * name entry. Try to replace it. */
                rc = lfsck_namespace_replace_cond(env, com, parent, child,
-                                                 tfid, cname);
+                                                 &tfid, cname);
                if (rc == 0)
                        rc = lfsck_namespace_dsd_orphan(env, com, child,
                                                        pfid, lh, type);
@@ -2554,6 +2589,9 @@ lost_parent:
                GOTO(out, rc);
        }
 
+       if (fid_is_zero(pfid))
+               GOTO(out, rc = 0);
+
        /* The ".." name entry is wrong, update it. */
        if (!lu_fid_eq(pfid, lfsck_dto2fid(parent))) {
                if (!lustre_handle_is_used(lh) && retry != NULL) {
@@ -2612,27 +2650,29 @@ lfsck_namespace_dsd_multiple(const struct lu_env *env,
        struct lfsck_thread_info *info          = lfsck_env_info(env);
        struct lu_name           *cname         = &info->lti_name;
        const struct lu_fid      *cfid          = lfsck_dto2fid(child);
-       struct lu_fid            *tfid          = &info->lti_fid3;
-       struct lu_fid            *pfid2         = &info->lti_fid4;
+       struct lu_fid            *pfid2         = &info->lti_fid3;
+       struct lu_fid             tfid;
        struct lfsck_namespace   *ns            = com->lc_file_ram;
        struct lfsck_instance    *lfsck         = com->lc_lfsck;
        struct lfsck_bookmark    *bk            = &lfsck->li_bookmark_ram;
        struct dt_object         *parent        = NULL;
-       struct linkea_data        ldata_new     = { 0 };
-       int                       count         = 0;
+       struct linkea_data        ldata_new     = { NULL };
+       int                       dirent_count  = 0;
+       int                       linkea_count  = 0;
        int                       rc            = 0;
        bool                      once          = true;
        ENTRY;
 
 again:
        while (ldata->ld_lee != NULL) {
-               lfsck_namespace_unpack_linkea_entry(ldata, cname, tfid,
+               lfsck_namespace_unpack_linkea_entry(ldata, cname, &tfid,
                                                    info->lti_key);
                /* Drop repeated linkEA entries. */
-               lfsck_namespace_filter_linkea_entry(ldata, cname, tfid, true);
+               lfsck_namespace_filter_linkea_entry(ldata, cname, &tfid, true);
                /* Drop invalid linkEA entry. */
-               if (!fid_is_sane(tfid)) {
+               if (!fid_is_sane(&tfid)) {
                        linkea_del_buf(ldata, cname);
+                       linkea_count++;
                        continue;
                }
 
@@ -2649,12 +2689,12 @@ again:
                 * When the LFSCK runs again, if the dangling name is still
                 * there, the LFSCK should move the orphan directory object
                 * back to the normal namespace. */
-               if (!lpf && !lu_fid_eq(pfid, tfid) && once) {
+               if (!lpf && !lu_fid_eq(pfid, &tfid) && once) {
                        linkea_next_entry(ldata);
                        continue;
                }
 
-               parent = lfsck_object_find_bottom(env, lfsck, tfid);
+               parent = lfsck_object_find_bottom(env, lfsck, &tfid);
                if (IS_ERR(parent))
                        RETURN(PTR_ERR(parent));
 
@@ -2666,6 +2706,7 @@ again:
                                 * child to be visible via other parent, then
                                 * remove this linkEA entry. */
                                linkea_del_buf(ldata, cname);
+                               linkea_count++;
                                continue;
                        }
 
@@ -2676,12 +2717,12 @@ again:
                if (unlikely(!dt_try_as_dir(env, parent))) {
                        lfsck_object_put(env, parent);
                        linkea_del_buf(ldata, cname);
+                       linkea_count++;
                        continue;
                }
 
-               rc = dt_lookup(env, parent, (struct dt_rec *)tfid,
-                              (const struct dt_key *)cname->ln_name,
-                              BYPASS_CAPA);
+               rc = dt_lookup(env, parent, (struct dt_rec *)&tfid,
+                              (const struct dt_key *)cname->ln_name);
                *pfid2 = *lfsck_dto2fid(parent);
                if (rc == -ENOENT) {
                        lfsck_object_put(env, parent);
@@ -2695,7 +2736,7 @@ again:
                        RETURN(rc);
                }
 
-               if (lu_fid_eq(tfid, cfid)) {
+               if (lu_fid_eq(&tfid, cfid)) {
                        lfsck_object_put(env, parent);
                        if (!lu_fid_eq(pfid, pfid2)) {
                                *type = LNIT_UNMATCHED_PAIRS;
@@ -2723,17 +2764,18 @@ rebuild:
                                RETURN(rc);
 
                        linkea_del_buf(ldata, cname);
+                       linkea_count++;
                        linkea_first_entry(ldata);
                        /* There may be some invalid dangling name entries under
                         * other parent directories, remove all of them. */
                        while (ldata->ld_lee != NULL) {
                                lfsck_namespace_unpack_linkea_entry(ldata,
-                                               cname, tfid, info->lti_key);
-                               if (!fid_is_sane(tfid))
+                                               cname, &tfid, info->lti_key);
+                               if (!fid_is_sane(&tfid))
                                        goto next;
 
                                parent = lfsck_object_find_bottom(env, lfsck,
-                                                                 tfid);
+                                                                 &tfid);
                                if (IS_ERR(parent)) {
                                        rc = PTR_ERR(parent);
                                        if (rc != -ENOENT &&
@@ -2759,13 +2801,13 @@ rebuild:
                                        goto next;
                                }
 
-                               count += rc;
+                               dirent_count += rc;
 
 next:
                                linkea_del_buf(ldata, cname);
                        }
 
-                       ns->ln_dirent_repaired += count;
+                       ns->ln_dirent_repaired += dirent_count;
 
                        RETURN(rc);
                }
@@ -2775,7 +2817,7 @@ next:
                 * created by the LFSCK for repairing dangling name entry.
                 * Try to replace it. */
                rc = lfsck_namespace_replace_cond(env, com, parent, child,
-                                                 tfid, cname);
+                                                 &tfid, cname);
                lfsck_object_put(env, parent);
                if (rc < 0)
                        RETURN(rc);
@@ -2786,10 +2828,15 @@ next:
                linkea_del_buf(ldata, cname);
        }
 
+       linkea_first_entry(ldata);
        if (ldata->ld_leh->leh_reccount == 1) {
                rc = lfsck_namespace_dsd_single(env, com, child, pfid, ldata,
                                                lh, type, NULL);
 
+               if (rc == 0 && fid_is_zero(pfid) && linkea_count > 0)
+                       rc = lfsck_namespace_rebuild_linkea(env, com, child,
+                                                           ldata);
+
                RETURN(rc);
        }
 
@@ -2802,7 +2849,6 @@ next:
                RETURN(rc);
        }
 
-       linkea_first_entry(ldata);
        /* If the dangling name entry for the orphan directory object has
         * been remvoed, then just check whether the directory object is
         * still under the .lustre/lost+found/MDTxxxx/ or not. */
@@ -2834,7 +2880,7 @@ next:
  * \param[in] env      pointer to the thread context
  * \param[in] com      pointer to the lfsck component
  * \param[in] obj      pointer to the dt_object to be handled
- * \param[in,out] nlink        pointer to buffer to object's hard lock count before
+ * \param[in,out] la   pointer to buffer to object's attribute before
  *                     and after the repairing
  *
  * \retval             positive number for repaired cases
@@ -2843,20 +2889,20 @@ next:
  */
 static int lfsck_namespace_repair_nlink(const struct lu_env *env,
                                        struct lfsck_component *com,
-                                       struct dt_object *obj, __u32 *nlink)
+                                       struct dt_object *obj,
+                                       struct lu_attr *la)
 {
        struct lfsck_thread_info        *info   = lfsck_env_info(env);
-       struct lu_attr                  *la     = &info->lti_la3;
        struct lu_fid                   *tfid   = &info->lti_fid3;
        struct lfsck_namespace          *ns     = com->lc_file_ram;
        struct lfsck_instance           *lfsck  = com->lc_lfsck;
-       struct dt_device                *dev    = lfsck->li_bottom;
+       struct dt_device                *dev    = lfsck_obj2dev(obj);
        const struct lu_fid             *cfid   = lfsck_dto2fid(obj);
-       struct dt_object                *child  = NULL;
        struct thandle                  *th     = NULL;
-       struct linkea_data               ldata  = { 0 };
+       struct linkea_data               ldata  = { NULL };
        struct lustre_handle             lh     = { 0 };
-       __u32                            old    = *nlink;
+       __u32                            old    = la->la_nlink;
+       int                              idx;
        int                              rc     = 0;
        __u8                             flags;
        ENTRY;
@@ -2864,13 +2910,8 @@ static int lfsck_namespace_repair_nlink(const struct lu_env *env,
        LASSERT(!dt_object_remote(obj));
        LASSERT(S_ISREG(lfsck_object_type(obj)));
 
-       child = lfsck_object_find_by_dev(env, dev, cfid);
-       if (IS_ERR(child))
-               GOTO(log, rc = PTR_ERR(child));
-
-       rc = lfsck_ibits_lock(env, lfsck, child, &lh,
-                             MDS_INODELOCK_UPDATE |
-                             MDS_INODELOCK_XATTR, LCK_EX);
+       rc = lfsck_ibits_lock(env, lfsck, obj, &lh,
+                             MDS_INODELOCK_UPDATE, LCK_PW);
        if (rc != 0)
                GOTO(log, rc);
 
@@ -2879,7 +2920,7 @@ static int lfsck_namespace_repair_nlink(const struct lu_env *env,
                GOTO(log, rc = PTR_ERR(th));
 
        la->la_valid = LA_NLINK;
-       rc = dt_declare_attr_set(env, child, la, th);
+       rc = dt_declare_attr_set(env, obj, la, th);
        if (rc != 0)
                GOTO(stop, rc);
 
@@ -2887,7 +2928,7 @@ static int lfsck_namespace_repair_nlink(const struct lu_env *env,
        if (rc != 0)
                GOTO(stop, rc);
 
-       dt_write_lock(env, child, 0);
+       dt_write_lock(env, obj, 0);
        /* If the LFSCK is marked as LF_INCOMPLETE, then means some MDT has
         * ever tried to verify some remote MDT-object that resides on this
         * MDT, but this MDT failed to respond such request. So means there
@@ -2899,46 +2940,46 @@ static int lfsck_namespace_repair_nlink(const struct lu_env *env,
                GOTO(unlock, rc = 0);
 
        fid_cpu_to_be(tfid, cfid);
-       rc = dt_lookup(env, com->lc_obj, (struct dt_rec *)&flags,
-                      (const struct dt_key *)tfid, BYPASS_CAPA);
+       idx = lfsck_sub_trace_file_fid2idx(cfid);
+       rc = dt_lookup(env, com->lc_sub_trace_objs[idx].lsto_obj,
+                      (struct dt_rec *)&flags, (const struct dt_key *)tfid);
        if (rc != 0)
                GOTO(unlock, rc);
 
        if (flags & LNTF_SKIP_NLINK)
                GOTO(unlock, rc = 0);
 
-       rc = lfsck_links_read2(env, child, &ldata);
-       if (rc == -ENODATA)
-               GOTO(unlock, rc = 0);
+       rc = dt_attr_get(env, obj, la);
+       if (rc != 0)
+               GOTO(unlock, rc = (rc == -ENOENT ? 0 : rc));
 
+       rc = lfsck_links_read2(env, obj, &ldata);
        if (rc != 0)
-               GOTO(unlock, rc);
+               GOTO(unlock, rc = (rc == -ENODATA ? 0 : rc));
 
-       if (*nlink == ldata.ld_leh->leh_reccount)
+       if (la->la_nlink == ldata.ld_leh->leh_reccount ||
+           unlikely(la->la_nlink == 0))
                GOTO(unlock, rc = 0);
 
-       la->la_nlink = *nlink = ldata.ld_leh->leh_reccount;
+       la->la_nlink = ldata.ld_leh->leh_reccount;
        if (lfsck->li_bookmark_ram.lb_param & LPF_DRYRUN)
                GOTO(unlock, rc = 1);
 
-       rc = dt_attr_set(env, child, la, th, BYPASS_CAPA);
+       rc = dt_attr_set(env, obj, la, th);
 
        GOTO(unlock, rc = (rc == 0 ? 1 : rc));
 
 unlock:
-       dt_write_unlock(env, child);
+       dt_write_unlock(env, obj);
 
 stop:
        dt_trans_stop(env, dev, th);
 
 log:
-       lfsck_ibits_unlock(&lh, LCK_EX);
-       if (child != NULL && !IS_ERR(child))
-               lfsck_object_put(env, child);
-
+       lfsck_ibits_unlock(&lh, LCK_PW);
        CDEBUG(D_LFSCK, "%s: namespace LFSCK repaired the object "DFID"'s "
               "nlink count from %u to %u: rc = %d\n",
-              lfsck_lfsck2name(lfsck), PFID(cfid), old, *nlink, rc);
+              lfsck_lfsck2name(lfsck), PFID(cfid), old, la->la_nlink, rc);
 
        if (rc != 0)
                ns->ln_flags |= LF_INCONSISTENT;
@@ -2993,7 +3034,7 @@ static int lfsck_namespace_double_scan_dir(const struct lu_env *env,
        struct lfsck_namespace   *ns            = com->lc_file_ram;
        struct lfsck_instance    *lfsck         = com->lc_lfsck;
        struct lustre_handle      lh            = { 0 };
-       struct linkea_data        ldata         = { 0 };
+       struct linkea_data        ldata         = { NULL };
        bool                      unknown       = false;
        bool                      lpf           = false;
        bool                      retry         = false;
@@ -3054,7 +3095,7 @@ lock:
        }
 
        rc = dt_lookup(env, child, (struct dt_rec *)pfid,
-                      (const struct dt_key *)dotdot, BYPASS_CAPA);
+                      (const struct dt_key *)dotdot);
        if (rc != 0) {
                if (rc != -ENOENT && rc != -ENODATA && rc != -EINVAL) {
                        dt_read_unlock(env, child);
@@ -3071,6 +3112,8 @@ lock:
        } else if (lfsck->li_lpf_obj != NULL &&
                   lu_fid_eq(pfid, lfsck_dto2fid(lfsck->li_lpf_obj))) {
                lpf = true;
+       } else if (unlikely(!fid_is_sane(pfid))) {
+               fid_zero(pfid);
        }
 
        rc = lfsck_links_read(env, child, &ldata);
@@ -3223,7 +3266,7 @@ static int lfsck_namespace_double_scan_one(const struct lu_env *env,
        struct lfsck_instance    *lfsck    = com->lc_lfsck;
        struct lfsck_namespace   *ns       = com->lc_file_ram;
        struct dt_object         *parent   = NULL;
-       struct linkea_data        ldata    = { 0 };
+       struct linkea_data        ldata    = { NULL };
        bool                      repaired = false;
        int                       count    = 0;
        int                       rc;
@@ -3314,7 +3357,7 @@ lost_parent:
                                }
 
                                /* Create the lost parent as an orphan. */
-                               rc = lfsck_namespace_create_orphan(env, com,
+                               rc = lfsck_namespace_create_orphan_dir(env, com,
                                                                parent, NULL);
                                if (rc < 0) {
                                        lfsck_object_put(env, parent);
@@ -3369,8 +3412,7 @@ lost_parent:
                }
 
                rc = dt_lookup(env, parent, (struct dt_rec *)cfid,
-                              (const struct dt_key *)cname->ln_name,
-                              BYPASS_CAPA);
+                              (const struct dt_key *)cname->ln_name);
                if (rc != 0 && rc != -ENOENT) {
                        lfsck_object_put(env, parent);
 
@@ -3413,7 +3455,7 @@ lost_parent:
                        continue;
                }
 
-               rc = dt_attr_get(env, child, la, BYPASS_CAPA);
+               rc = dt_attr_get(env, child, la);
                if (rc != 0)
                        GOTO(out, rc);
 
@@ -3514,37 +3556,38 @@ out:
                count = ldata.ld_leh->leh_reccount;
        }
 
-       /* If the LFSCK is marked as LF_INCOMPLETE, then means some
-        * MDT has ever tried to verify some remote MDT-object that
-        * resides on this MDT, but this MDT failed to respond such
-        * request. So means there may be some remote name entry on
-        * other MDT that references this object with another name,
-        * so we cannot know whether this linkEA is valid or not.
-        * So keep it there and maybe resolved when next LFSCK run. */
-       if (count == 0 && !(ns->ln_flags & LF_INCOMPLETE)) {
-               /* If the child becomes orphan, then insert it into
-                * the global .lustre/lost+found/MDTxxxx directory. */
-               rc = lfsck_namespace_insert_orphan(env, com, child, "", "O",
-                                                  &count);
-               if (rc < 0)
-                       return rc;
+       if (count == 0) {
+               /* If the LFSCK is marked as LF_INCOMPLETE, then means some
+                * MDT has ever tried to verify some remote MDT-object that
+                * resides on this MDT, but this MDT failed to respond such
+                * request. So means there may be some remote name entry on
+                * other MDT that references this object with another name,
+                * so we cannot know whether this linkEA is valid or not.
+                * So keep it there and maybe resolved when next LFSCK run. */
+               if (!(ns->ln_flags & LF_INCOMPLETE)) {
+                       /* If the child becomes orphan, then insert it into
+                        * the global .lustre/lost+found/MDTxxxx directory. */
+                       rc = lfsck_namespace_insert_orphan(env, com, child,
+                                                          "", "O", &count);
+                       if (rc < 0)
+                               return rc;
 
-               if (rc > 0) {
-                       ns->ln_mul_ref_repaired++;
-                       repaired = true;
+                       if (rc > 0) {
+                               ns->ln_mul_ref_repaired++;
+                               repaired = true;
+                       }
                }
-       }
-
-       rc = dt_attr_get(env, child, la, BYPASS_CAPA);
-       if (rc != 0)
-               return rc;
+       } else {
+               rc = dt_attr_get(env, child, la);
+               if (rc != 0)
+                       return rc;
 
-       if (la->la_nlink != count) {
-               rc = lfsck_namespace_repair_nlink(env, com, child,
-                                                 &la->la_nlink);
-               if (rc > 0) {
-                       ns->ln_objs_nlink_repaired++;
-                       rc = 0;
+               if (la->la_nlink != 0 && la->la_nlink != count) {
+                       rc = lfsck_namespace_repair_nlink(env, com, child, la);
+                       if (rc > 0) {
+                               ns->ln_objs_nlink_repaired++;
+                               rc = 0;
+                       }
                }
        }
 
@@ -3661,6 +3704,33 @@ static void lfsck_namespace_release_lmv(const struct lu_env *env,
        }
 }
 
+static int lfsck_namespace_check_for_double_scan(const struct lu_env *env,
+                                                struct lfsck_component *com,
+                                                struct dt_object *obj)
+{
+       struct lu_attr *la = &lfsck_env_info(env)->lti_la;
+       int             rc;
+
+       rc = dt_attr_get(env, obj, la);
+       if (rc != 0)
+               return rc;
+
+       /* zero-linkEA object may be orphan, but it also maybe because
+        * of upgrading. Currently, we cannot record it for double scan.
+        * Because it may cause the LFSCK trace file to be too large. */
+
+       /* "la_ctime" == 1 means that it has ever been removed from
+        * backend /lost+found directory but not been added back to
+        * the normal namespace yet. */
+
+       if ((S_ISREG(lfsck_object_type(obj)) && la->la_nlink > 1) ||
+           unlikely(la->la_ctime == 1))
+               rc = lfsck_namespace_trace_update(env, com, lfsck_dto2fid(obj),
+                                                 LNTF_CHECK_LINKEA, true);
+
+       return rc;
+}
+
 /* namespace APIs */
 
 static int lfsck_namespace_reset(const struct lu_env *env,
@@ -3695,29 +3765,22 @@ static int lfsck_namespace_reset(const struct lu_env *env,
        ns->ln_magic = LFSCK_NAMESPACE_MAGIC;
        ns->ln_status = LS_INIT;
 
-       rc = local_object_unlink(env, lfsck->li_bottom, root,
-                                lfsck_namespace_name);
-       if (rc != 0)
-               GOTO(out, rc);
-
        lfsck_object_put(env, com->lc_obj);
        com->lc_obj = NULL;
-       dto = local_index_find_or_create(env, lfsck->li_los, root,
-                                        lfsck_namespace_name,
-                                        S_IFREG | S_IRUGO | S_IWUSR,
-                                        &dt_lfsck_features);
+       dto = lfsck_namespace_load_one_trace_file(env, com, root,
+                                                 LFSCK_NAMESPACE, true);
        if (IS_ERR(dto))
                GOTO(out, rc = PTR_ERR(dto));
 
        com->lc_obj = dto;
-       rc = dto->do_ops->do_index_try(env, dto, &dt_lfsck_features);
+       rc = lfsck_namespace_load_sub_trace_files(env, com, true);
        if (rc != 0)
                GOTO(out, rc);
 
        lad->lad_incomplete = 0;
        CFS_RESET_BITMAP(lad->lad_bitmap);
 
-       rc = lfsck_namespace_store(env, com);
+       rc = lfsck_namespace_store(env, com, true);
 
        GOTO(out, rc);
 
@@ -3725,7 +3788,7 @@ out:
        up_write(&com->lc_sem);
 
 put:
-       lu_object_put(env, &root->do_lu);
+       lfsck_object_put(env, root);
 log:
        CDEBUG(D_LFSCK, "%s: namespace LFSCK reset: rc = %d\n",
               lfsck_lfsck2name(lfsck), rc);
@@ -3750,6 +3813,7 @@ static void lfsck_namespace_close_dir(const struct lu_env *env,
 {
        struct lfsck_namespace          *ns     = com->lc_file_ram;
        struct lfsck_assistant_data     *lad    = com->lc_data;
+       struct lfsck_assistant_object   *lso    = NULL;
        struct lfsck_instance           *lfsck  = com->lc_lfsck;
        struct lfsck_lmv                *llmv   = lfsck->li_lmv;
        struct lfsck_namespace_req      *lnr;
@@ -3768,13 +3832,21 @@ static void lfsck_namespace_close_dir(const struct lu_env *env,
                RETURN_EXIT;
        }
 
+       lso = lfsck_assistant_object_init(env, lfsck_dto2fid(lfsck->li_obj_dir),
+                       NULL, lfsck->li_pos_current.lp_oit_cookie, true);
+       if (IS_ERR(lso)) {
+               OBD_FREE(lnr, size);
+               ns->ln_striped_dirs_skipped++;
+
+               RETURN_EXIT;
+       }
+
        /* Generate a dummy request to indicate that all shards' name entry
         * in this striped directory has been scanned for the first time. */
        INIT_LIST_HEAD(&lnr->lnr_lar.lar_list);
-       lnr->lnr_obj = lfsck_object_get(lfsck->li_obj_dir);
+       lnr->lnr_lar.lar_parent = lso;
        lnr->lnr_lmv = lfsck_lmv_get(llmv);
        lnr->lnr_fid = *lfsck_dto2fid(lfsck->li_obj_dir);
-       lnr->lnr_oit_cookie = lfsck->li_pos_current.lp_oit_cookie;
        lnr->lnr_dir_cookie = MDS_DIR_END_OFF;
        lnr->lnr_size = size;
 
@@ -3814,10 +3886,9 @@ static int lfsck_namespace_open_dir(const struct lu_env *env,
        if (llmv->ll_lmv_master) {
                struct lmv_mds_md_v1 *lmv = &llmv->ll_lmv;
 
-               if (lmv->lmv_master_mdt_index !=
-                   lfsck_dev_idx(lfsck->li_bottom)) {
+               if (lmv->lmv_master_mdt_index != lfsck_dev_idx(lfsck)) {
                        lmv->lmv_master_mdt_index =
-                               lfsck_dev_idx(lfsck->li_bottom);
+                               lfsck_dev_idx(lfsck);
                        ns->ln_flags |= LF_INCONSISTENT;
                        llmv->ll_lmv_updated = 1;
                }
@@ -3854,7 +3925,7 @@ static int lfsck_namespace_checkpoint(const struct lu_env *env,
                com->lc_new_checked = 0;
        }
 
-       rc = lfsck_namespace_store(env, com);
+       rc = lfsck_namespace_store(env, com, false);
        up_write(&com->lc_sem);
 
 log:
@@ -3976,15 +4047,12 @@ static int lfsck_namespace_exec_oit(const struct lu_env *env,
        struct lfsck_namespace   *ns    = com->lc_file_ram;
        struct lfsck_instance    *lfsck = com->lc_lfsck;
        const struct lu_fid      *fid   = lfsck_dto2fid(obj);
-       struct lu_attr           *la    = &info->lti_la;
        struct lu_fid            *pfid  = &info->lti_fid2;
        struct lu_name           *cname = &info->lti_name;
        struct lu_seq_range      *range = &info->lti_range;
-       struct dt_device         *dev   = lfsck->li_bottom;
-       struct seq_server_site   *ss    =
-                               lu_site2seq(dev->dd_lu_dev.ld_site);
-       struct linkea_data        ldata = { 0 };
-       __u32                     idx   = lfsck_dev_idx(dev);
+       struct seq_server_site   *ss    = lfsck_dev_site(lfsck);
+       struct linkea_data        ldata = { NULL };
+       __u32                     idx   = lfsck_dev_idx(lfsck);
        int                       rc;
        ENTRY;
 
@@ -4012,23 +4080,8 @@ static int lfsck_namespace_exec_oit(const struct lu_env *env,
                GOTO(out, rc = (rc == -ENOENT ? 0 : rc));
        }
 
-       /* zero-linkEA object may be orphan, but it also maybe because
-        * of upgrading. Currently, we cannot record it for double scan.
-        * Because it may cause the LFSCK trace file to be too large. */
        if (rc == -ENODATA) {
-               if (S_ISDIR(lfsck_object_type(obj)))
-                       GOTO(out, rc = 0);
-
-               rc = dt_attr_get(env, obj, la, BYPASS_CAPA);
-               if (rc != 0)
-                       GOTO(out, rc);
-
-               /* "la_ctime" == 1 means that it has ever been removed from
-                * backend /lost+found directory but not been added back to
-                * the normal namespace yet. */
-               if (la->la_nlink > 1 || unlikely(la->la_ctime == 1))
-                       rc = lfsck_namespace_trace_update(env, com, fid,
-                                               LNTF_CHECK_LINKEA, true);
+               rc = lfsck_namespace_check_for_double_scan(env, com, obj);
 
                GOTO(out, rc);
        }
@@ -4054,31 +4107,18 @@ static int lfsck_namespace_exec_oit(const struct lu_env *env,
                rc = fld_local_lookup(env, ss->ss_server_fld,
                                      fid_seq(pfid), range);
                if ((rc == -ENOENT) ||
-                   (rc == 0 && range->lsr_index != idx)) {
+                   (rc == 0 && range->lsr_index != idx))
                        rc = lfsck_namespace_trace_update(env, com, fid,
                                                LNTF_CHECK_LINKEA, true);
-               } else {
-                       if (S_ISDIR(lfsck_object_type(obj)))
-                               GOTO(out, rc = 0);
-
-                       rc = dt_attr_get(env, obj, la, BYPASS_CAPA);
-                       if (rc != 0)
-                               GOTO(out, rc);
-
-                       /* "la_ctime" == 1 means that it has ever been
-                        * removed from backend /lost+found directory but
-                        * not been added back to the normal namespace yet. */
-                       if (la->la_nlink > 1 || unlikely(la->la_ctime == 1))
-                               rc = lfsck_namespace_trace_update(env, com,
-                                               fid, LNTF_CHECK_LINKEA, true);
-               }
+               else
+                       rc = lfsck_namespace_check_for_double_scan(env, com,
+                                                                  obj);
        }
 
        GOTO(out, rc);
 
 out:
        down_write(&com->lc_sem);
-       com->lc_new_checked++;
        if (S_ISDIR(lfsck_object_type(obj)))
                ns->ln_dirs_checked++;
        if (rc != 0)
@@ -4090,13 +4130,32 @@ out:
 
 static int lfsck_namespace_exec_dir(const struct lu_env *env,
                                    struct lfsck_component *com,
+                                   struct lfsck_assistant_object *lso,
                                    struct lu_dirent *ent, __u16 type)
 {
-       struct lfsck_assistant_data     *lad    = com->lc_data;
+       struct lfsck_assistant_data     *lad     = com->lc_data;
+       struct lfsck_instance           *lfsck   = com->lc_lfsck;
        struct lfsck_namespace_req      *lnr;
-       bool                             wakeup = false;
+       struct lfsck_bookmark           *bk      = &lfsck->li_bookmark_ram;
+       struct ptlrpc_thread            *mthread = &lfsck->li_thread;
+       struct ptlrpc_thread            *athread = &lad->lad_thread;
+       struct l_wait_info               lwi     = { 0 };
+       bool                             wakeup  = false;
+
+       l_wait_event(mthread->t_ctl_waitq,
+                    lad->lad_prefetched < bk->lb_async_windows ||
+                    !thread_is_running(mthread) ||
+                    thread_is_stopped(athread),
+                    &lwi);
+
+       if (unlikely(!thread_is_running(mthread)) ||
+                    thread_is_stopped(athread))
+               return 0;
+
+       if (unlikely(lfsck_is_dead_obj(lfsck->li_obj_dir)))
+               return 0;
 
-       lnr = lfsck_namespace_assistant_req_init(com->lc_lfsck, ent, type);
+       lnr = lfsck_namespace_assistant_req_init(com->lc_lfsck, lso, ent, type);
        if (IS_ERR(lnr)) {
                struct lfsck_namespace *ns = com->lc_file_ram;
 
@@ -4174,7 +4233,7 @@ static int lfsck_namespace_post(const struct lu_env *env,
                com->lc_new_checked = 0;
        }
 
-       rc = lfsck_namespace_store(env, com);
+       rc = lfsck_namespace_store(env, com, false);
        up_write(&com->lc_sem);
 
        CDEBUG(D_LFSCK, "%s: namespace LFSCK post done: rc = %d\n",
@@ -4210,17 +4269,17 @@ lfsck_namespace_dump(const struct lu_env *env, struct lfsck_component *com,
                goto out;
 
        rc = lfsck_time_dump(m, ns->ln_time_last_complete,
-                            "time_since_last_completed");
+                            "last_completed");
        if (rc < 0)
                goto out;
 
        rc = lfsck_time_dump(m, ns->ln_time_latest_start,
-                            "time_since_latest_start");
+                            "latest_start");
        if (rc < 0)
                goto out;
 
        rc = lfsck_time_dump(m, ns->ln_time_last_checkpoint,
-                            "time_since_last_checkpoint");
+                            "last_checkpoint");
        if (rc < 0)
                goto out;
 
@@ -4246,24 +4305,25 @@ lfsck_namespace_dump(const struct lu_env *env, struct lfsck_component *com,
                                          lfsck->li_time_last_checkpoint;
                __u64 checked = ns->ln_items_checked + com->lc_new_checked;
                __u64 speed = checked;
-               __u64 new_checked = msecs_to_jiffies(com->lc_new_checked *
-                                                    MSEC_PER_SEC);
+               __u64 new_checked = com->lc_new_checked *
+                                   msecs_to_jiffies(MSEC_PER_SEC);
                __u32 rtime = ns->ln_run_time_phase1 +
                              cfs_duration_sec(duration + HALF_SEC);
 
                if (duration != 0)
                        do_div(new_checked, duration);
+
                if (rtime != 0)
                        do_div(speed, rtime);
-               lfsck_namespace_dump_statistics(m, ns, checked,
-                                               ns->ln_objs_checked_phase2,
-                                               rtime, ns->ln_run_time_phase2);
 
+               lfsck_namespace_dump_statistics(m, ns, checked, 0, rtime, 0);
                seq_printf(m, "average_speed_phase1: "LPU64" items/sec\n"
                              "average_speed_phase2: N/A\n"
+                             "average_speed_total: "LPU64" items/sec\n"
                              "real_time_speed_phase1: "LPU64" items/sec\n"
                              "real_time_speed_phase2: N/A\n",
                              speed,
+                             speed,
                              new_checked);
 
                LASSERT(lfsck->li_di_oit != NULL);
@@ -4296,55 +4356,80 @@ lfsck_namespace_dump(const struct lu_env *env, struct lfsck_component *com,
                lfsck_pos_dump(m, &pos, "current_position");
        } else if (ns->ln_status == LS_SCANNING_PHASE2) {
                cfs_duration_t duration = cfs_time_current() -
-                                         lfsck->li_time_last_checkpoint;
+                                         com->lc_time_last_checkpoint;
                __u64 checked = ns->ln_objs_checked_phase2 +
                                com->lc_new_checked;
                __u64 speed1 = ns->ln_items_checked;
                __u64 speed2 = checked;
-               __u64 new_checked = msecs_to_jiffies(com->lc_new_checked *
-                                                    MSEC_PER_SEC);
+               __u64 speed0 = speed1 + speed2;
+               __u64 new_checked = com->lc_new_checked *
+                                   msecs_to_jiffies(MSEC_PER_SEC);
                __u32 rtime = ns->ln_run_time_phase2 +
                              cfs_duration_sec(duration + HALF_SEC);
+               __u32 time0 = ns->ln_run_time_phase1 + rtime;
 
                if (duration != 0)
                        do_div(new_checked, duration);
+
                if (ns->ln_run_time_phase1 != 0)
                        do_div(speed1, ns->ln_run_time_phase1);
+               else if (ns->ln_items_checked != 0)
+                       time0++;
+
                if (rtime != 0)
                        do_div(speed2, rtime);
+               else if (checked != 0)
+                       time0++;
+
+               if (time0 != 0)
+                       do_div(speed0, time0);
+
                lfsck_namespace_dump_statistics(m, ns, ns->ln_items_checked,
                                                checked,
                                                ns->ln_run_time_phase1, rtime);
-
                seq_printf(m, "average_speed_phase1: "LPU64" items/sec\n"
                              "average_speed_phase2: "LPU64" objs/sec\n"
+                             "average_speed_total: "LPU64" items/sec\n"
                              "real_time_speed_phase1: N/A\n"
                              "real_time_speed_phase2: "LPU64" objs/sec\n"
                              "current_position: "DFID"\n",
                              speed1,
                              speed2,
+                             speed0,
                              new_checked,
                              PFID(&ns->ln_fid_latest_scanned_phase2));
        } else {
                __u64 speed1 = ns->ln_items_checked;
                __u64 speed2 = ns->ln_objs_checked_phase2;
+               __u64 speed0 = speed1 + speed2;
+               __u32 time0 = ns->ln_run_time_phase1 + ns->ln_run_time_phase2;
 
                if (ns->ln_run_time_phase1 != 0)
                        do_div(speed1, ns->ln_run_time_phase1);
+               else if (ns->ln_items_checked != 0)
+                       time0++;
+
                if (ns->ln_run_time_phase2 != 0)
                        do_div(speed2, ns->ln_run_time_phase2);
+               else if (ns->ln_objs_checked_phase2 != 0)
+                       time0++;
+
+               if (time0 != 0)
+                       do_div(speed0, time0);
+
                lfsck_namespace_dump_statistics(m, ns, ns->ln_items_checked,
                                                ns->ln_objs_checked_phase2,
                                                ns->ln_run_time_phase1,
                                                ns->ln_run_time_phase2);
-
                seq_printf(m, "average_speed_phase1: "LPU64" items/sec\n"
                              "average_speed_phase2: "LPU64" objs/sec\n"
+                             "average_speed_total: "LPU64" items/sec\n"
                              "real_time_speed_phase1: N/A\n"
                              "real_time_speed_phase2: N/A\n"
                              "current_position: N/A\n",
                              speed1,
-                             speed2);
+                             speed2,
+                             speed0);
        }
 out:
        up_read(&com->lc_sem);
@@ -4454,86 +4539,56 @@ static int lfsck_namespace_in_notify(const struct lu_env *env,
        struct lfsck_assistant_data     *lad   = com->lc_data;
        struct lfsck_tgt_descs          *ltds  = &lfsck->li_mdt_descs;
        struct lfsck_tgt_desc           *ltd;
-       int                              rc;
+       int                              rc    = 0;
        bool                             fail  = false;
        ENTRY;
 
        switch (lr->lr_event) {
-       case LE_CREATE_ORPHAN: {
-               struct dt_object *orphan = NULL;
-               struct lmv_mds_md_v1 *lmv;
-
-               CDEBUG(D_LFSCK, "%s: namespace LFSCK handling notify from "
-                      "MDT %x to create orphan"DFID" with type %o\n",
-                      lfsck_lfsck2name(lfsck), lr->lr_index,
-                      PFID(&lr->lr_fid), lr->lr_type);
-
-               orphan = lfsck_object_find(env, lfsck, &lr->lr_fid);
-               if (IS_ERR(orphan))
-                       GOTO(out_create, rc = PTR_ERR(orphan));
-
-               if (dt_object_exists(orphan))
-                       GOTO(out_create, rc = -EEXIST);
-
-               if (lr->lr_stripe_count > 0) {
-                       lmv = &lfsck_env_info(env)->lti_lmv;
-                       memset(lmv, 0, sizeof(*lmv));
-                       lmv->lmv_hash_type = lr->lr_hash_type;
-                       lmv->lmv_stripe_count = lr->lr_stripe_count;
-                       lmv->lmv_layout_version = lr->lr_layout_version;
-                       memcpy(lmv->lmv_pool_name, lr->lr_pool_name,
-                              sizeof(lmv->lmv_pool_name));
-               } else {
-                       lmv = NULL;
-               }
-
-               rc = lfsck_namespace_create_orphan_local(env, com, orphan,
-                                                        lr->lr_type, lmv);
-
-               GOTO(out_create, rc = (rc == 1) ? 0 : rc);
-
-out_create:
-               CDEBUG(D_LFSCK, "%s: namespace LFSCK handled notify from "
-                      "MDT %x to create orphan"DFID" with type %o: rc = %d\n",
-                      lfsck_lfsck2name(lfsck), lr->lr_index,
-                      PFID(&lr->lr_fid), lr->lr_type, rc);
-
-               if (orphan != NULL && !IS_ERR(orphan))
-                       lfsck_object_put(env, orphan);
-
-               return rc;
-       }
        case LE_SKIP_NLINK_DECLARE: {
-               struct dt_object        *obj   = com->lc_obj;
+               struct dt_object        *obj;
                struct lu_fid           *key   = &lfsck_env_info(env)->lti_fid3;
+               int                      idx;
                __u8                     flags = 0;
 
                LASSERT(th != NULL);
 
+               idx = lfsck_sub_trace_file_fid2idx(&lr->lr_fid);
+               obj = com->lc_sub_trace_objs[idx].lsto_obj;
+               fid_cpu_to_be(key, &lr->lr_fid);
+               mutex_lock(&com->lc_sub_trace_objs[idx].lsto_mutex);
                rc = dt_declare_delete(env, obj,
                                       (const struct dt_key *)key, th);
                if (rc == 0)
                        rc = dt_declare_insert(env, obj,
                                               (const struct dt_rec *)&flags,
                                               (const struct dt_key *)key, th);
+               mutex_unlock(&com->lc_sub_trace_objs[idx].lsto_mutex);
 
                RETURN(rc);
        }
        case LE_SKIP_NLINK: {
-               struct dt_object        *obj   = com->lc_obj;
+               struct dt_object        *obj;
                struct lu_fid           *key   = &lfsck_env_info(env)->lti_fid3;
+               int                      idx;
                __u8                     flags = 0;
                bool                     exist = false;
                ENTRY;
 
                LASSERT(th != NULL);
 
+               idx = lfsck_sub_trace_file_fid2idx(&lr->lr_fid);
+               obj = com->lc_sub_trace_objs[idx].lsto_obj;
                fid_cpu_to_be(key, &lr->lr_fid);
+               mutex_lock(&com->lc_sub_trace_objs[idx].lsto_mutex);
                rc = dt_lookup(env, obj, (struct dt_rec *)&flags,
-                              (const struct dt_key *)key, BYPASS_CAPA);
+                              (const struct dt_key *)key);
                if (rc == 0) {
-                       if (flags & LNTF_SKIP_NLINK)
+                       if (flags & LNTF_SKIP_NLINK) {
+                               mutex_unlock(
+                               &com->lc_sub_trace_objs[idx].lsto_mutex);
+
                                RETURN(0);
+                       }
 
                        exist = true;
                } else if (rc != -ENOENT) {
@@ -4543,17 +4598,18 @@ out_create:
                flags |= LNTF_SKIP_NLINK;
                if (exist) {
                        rc = dt_delete(env, obj, (const struct dt_key *)key,
-                                      th, BYPASS_CAPA);
+                                      th);
                        if (rc != 0)
                                GOTO(log, rc);
                }
 
                rc = dt_insert(env, obj, (const struct dt_rec *)&flags,
-                              (const struct dt_key *)key, th, BYPASS_CAPA, 1);
+                              (const struct dt_key *)key, th, 1);
 
                GOTO(log, rc);
 
 log:
+               mutex_unlock(&com->lc_sub_trace_objs[idx].lsto_mutex);
                CDEBUG(D_LFSCK, "%s: RPC service thread mark the "DFID
                       " to be skipped for namespace double scan: rc = %d\n",
                       lfsck_lfsck2name(com->lc_lfsck), PFID(&lr->lr_fid), rc);
@@ -4570,12 +4626,14 @@ log:
        case LE_SET_LMV_MASTER: {
                struct dt_object        *obj;
 
-               obj = lfsck_object_find_by_dev(env, lfsck->li_bottom,
-                                              &lr->lr_fid);
+               obj = lfsck_object_find_bottom(env, lfsck, &lr->lr_fid);
                if (IS_ERR(obj))
                        RETURN(PTR_ERR(obj));
 
-               rc = lfsck_namespace_notify_lmv_master_local(env, com, obj);
+               if (likely(dt_object_exists(obj)))
+                       rc = lfsck_namespace_notify_lmv_master_local(env, com,
+                                                                    obj);
+
                lfsck_object_put(env, obj);
 
                RETURN(rc > 0 ? 0 : rc);
@@ -4602,7 +4660,7 @@ log:
               lr->lr_index, lr->lr_status, lr->lr_flags2);
 
        spin_lock(&ltds->ltd_lock);
-       ltd = LTD_TGT(ltds, lr->lr_index);
+       ltd = lfsck_ltd2tgt(ltds, lr->lr_index);
        if (ltd == NULL) {
                spin_unlock(&ltds->ltd_lock);
 
@@ -4708,6 +4766,8 @@ static struct lfsck_operations lfsck_namespace_ops = {
  *
  * \param[in] env      pointer to the thread context
  * \param[in] com      pointer to the lfsck component
+ * \param[in] parent   pointer to the dir object that contains the dangling
+ *                     name entry
  * \param[in] child    pointer to the object corresponding to the dangling
  *                     name entry
  * \param[in] lnr      pointer to the namespace request that contains the
@@ -4719,6 +4779,7 @@ static struct lfsck_operations lfsck_namespace_ops = {
  */
 int lfsck_namespace_repair_dangling(const struct lu_env *env,
                                    struct lfsck_component *com,
+                                   struct dt_object *parent,
                                    struct dt_object *child,
                                    struct lfsck_namespace_req *lnr)
 {
@@ -4728,15 +4789,16 @@ int lfsck_namespace_repair_dangling(const struct lu_env *env,
        struct dt_object_format         *dof    = &info->lti_dof;
        struct dt_insert_rec            *rec    = &info->lti_dt_rec;
        struct lmv_mds_md_v1            *lmv2   = &info->lti_lmv2;
-       struct dt_object                *parent = lnr->lnr_obj;
+       struct dt_object                *pobj   = NULL;
+       struct dt_object                *cobj   = NULL;
        const struct lu_name            *cname;
-       struct linkea_data               ldata  = { 0 };
-       struct lustre_handle             lh     = { 0 };
+       struct linkea_data               ldata  = { NULL };
+       struct lfsck_lock_handle        *llh    = &info->lti_llh;
        struct lu_buf                    linkea_buf;
        struct lu_buf                    lmv_buf;
        struct lfsck_instance           *lfsck  = com->lc_lfsck;
        struct lfsck_bookmark           *bk     = &lfsck->li_bookmark_ram;
-       struct dt_device                *dev    = lfsck_obj2dt_dev(child);
+       struct dt_device                *dev    = lfsck->li_next;
        struct thandle                  *th     = NULL;
        int                              rc     = 0;
        __u16                            type   = lnr->lnr_type;
@@ -4752,27 +4814,37 @@ int lfsck_namespace_repair_dangling(const struct lu_env *env,
        if (!create || bk->lb_param & LPF_DRYRUN)
                GOTO(log, rc = 0);
 
+       /* We may need to create the sub-objects of the @child via LOD,
+        * so make the modification based on lfsck->li_next. */
+
+       pobj = lfsck_object_locate(dev, parent);
+       if (IS_ERR(pobj))
+               GOTO(log, rc = PTR_ERR(pobj));
+
+       if (unlikely(!dt_try_as_dir(env, pobj)))
+               GOTO(log, rc = -ENOTDIR);
+
+       cobj = lfsck_object_locate(dev, child);
+       if (IS_ERR(cobj))
+               GOTO(log, rc = PTR_ERR(cobj));
+
        rc = linkea_data_new(&ldata, &info->lti_linkea_buf2);
        if (rc != 0)
                GOTO(log, rc);
 
-       rc = linkea_add_buf(&ldata, cname, lfsck_dto2fid(parent));
+       rc = linkea_add_buf(&ldata, cname, lfsck_dto2fid(pobj));
        if (rc != 0)
                GOTO(log, rc);
 
-       rc = lfsck_ibits_lock(env, lfsck, parent, &lh,
-                             MDS_INODELOCK_UPDATE, LCK_EX);
+       rc = lfsck_lock(env, lfsck, parent, lnr->lnr_name, llh,
+                       MDS_INODELOCK_UPDATE, LCK_PR);
        if (rc != 0)
                GOTO(log, rc);
 
-       rc = lfsck_namespace_check_exist(env, parent, child, lnr->lnr_name);
+       rc = lfsck_namespace_check_exist(env, pobj, cobj, lnr->lnr_name);
        if (rc != 0)
                GOTO(log, rc);
 
-       th = dt_trans_create(env, dev);
-       if (IS_ERR(th))
-               GOTO(log, rc = PTR_ERR(th));
-
        /* Set the ctime as zero, then others can know it is created for
         * repairing dangling name entry by LFSCK. And if the LFSCK made
         * wrong decision and the real MDT-object has been found later,
@@ -4782,8 +4854,8 @@ int lfsck_namespace_repair_dangling(const struct lu_env *env,
        la->la_valid = LA_TYPE | LA_MODE | LA_UID | LA_GID |
                        LA_ATIME | LA_MTIME | LA_CTIME;
 
-       child->do_ops->do_ah_init(env, hint, parent, child,
-                                 la->la_mode & S_IFMT);
+       cobj->do_ops->do_ah_init(env, hint, pobj, cobj,
+                                la->la_mode & S_IFMT);
 
        memset(dof, 0, sizeof(*dof));
        dof->dof_type = dt_mode_to_dft(type);
@@ -4791,34 +4863,38 @@ int lfsck_namespace_repair_dangling(const struct lu_env *env,
         * the MDT-object without stripes (dof->dof_reg.striped = 0). related
         * OST-objects will be created when write open. */
 
+       th = dt_trans_create(env, dev);
+       if (IS_ERR(th))
+               GOTO(log, rc = PTR_ERR(th));
+
        /* 1a. create child. */
-       rc = dt_declare_create(env, child, la, hint, dof, th);
+       rc = dt_declare_create(env, cobj, la, hint, dof, th);
        if (rc != 0)
                GOTO(stop, rc);
 
        if (S_ISDIR(type)) {
-               if (unlikely(!dt_try_as_dir(env, child)))
+               if (unlikely(!dt_try_as_dir(env, cobj)))
                        GOTO(stop, rc = -ENOTDIR);
 
                /* 2a. insert dot into child dir */
                rec->rec_type = S_IFDIR;
-               rec->rec_fid = lfsck_dto2fid(child);
-               rc = dt_declare_insert(env, child,
+               rec->rec_fid = lfsck_dto2fid(cobj);
+               rc = dt_declare_insert(env, cobj,
                                       (const struct dt_rec *)rec,
                                       (const struct dt_key *)dot, th);
                if (rc != 0)
                        GOTO(stop, rc);
 
                /* 3a. insert dotdot into child dir */
-               rec->rec_fid = lfsck_dto2fid(parent);
-               rc = dt_declare_insert(env, child,
+               rec->rec_fid = lfsck_dto2fid(pobj);
+               rc = dt_declare_insert(env, cobj,
                                       (const struct dt_rec *)rec,
                                       (const struct dt_key *)dotdot, th);
                if (rc != 0)
                        GOTO(stop, rc);
 
                /* 4a. increase child nlink */
-               rc = dt_declare_ref_add(env, child, th);
+               rc = dt_declare_ref_add(env, cobj, th);
                if (rc != 0)
                        GOTO(stop, rc);
 
@@ -4828,7 +4904,7 @@ int lfsck_namespace_repair_dangling(const struct lu_env *env,
 
                        idx = lfsck_shard_name_to_index(env,
                                        lnr->lnr_name, lnr->lnr_namelen,
-                                       type, lfsck_dto2fid(child));
+                                       type, lfsck_dto2fid(cobj));
                        if (unlikely(idx < 0))
                                GOTO(stop, rc = idx);
 
@@ -4838,7 +4914,7 @@ int lfsck_namespace_repair_dangling(const struct lu_env *env,
 
                        lfsck_lmv_header_cpu_to_le(lmv2, lmv2);
                        lfsck_buf_init(&lmv_buf, lmv2, sizeof(*lmv2));
-                       rc = dt_declare_xattr_set(env, child, &lmv_buf,
+                       rc = dt_declare_xattr_set(env, cobj, &lmv_buf,
                                                  XATTR_NAME_LMV, 0, th);
                        if (rc != 0)
                                GOTO(stop, rc);
@@ -4848,75 +4924,71 @@ int lfsck_namespace_repair_dangling(const struct lu_env *env,
        /* 6a. insert linkEA for child */
        lfsck_buf_init(&linkea_buf, ldata.ld_buf->lb_buf,
                       ldata.ld_leh->leh_len);
-       rc = dt_declare_xattr_set(env, child, &linkea_buf,
+       rc = dt_declare_xattr_set(env, cobj, &linkea_buf,
                                  XATTR_NAME_LINK, 0, th);
        if (rc != 0)
                GOTO(stop, rc);
 
-       rc = dt_trans_start(env, dev, th);
+       rc = dt_trans_start_local(env, dev, th);
        if (rc != 0)
                GOTO(stop, rc = (rc == -EEXIST ? 1 : rc));
 
-       dt_write_lock(env, child, 0);
+       dt_write_lock(env, cobj, 0);
        /* 1b. create child */
-       rc = dt_create(env, child, la, hint, dof, th);
+       rc = dt_create(env, cobj, la, hint, dof, th);
        if (rc != 0)
                GOTO(unlock, rc = (rc == -EEXIST ? 1 : rc));
 
        if (S_ISDIR(type)) {
-               if (unlikely(!dt_try_as_dir(env, child)))
-                       GOTO(unlock, rc = -ENOTDIR);
-
                /* 2b. insert dot into child dir */
                rec->rec_type = S_IFDIR;
-               rec->rec_fid = lfsck_dto2fid(child);
-               rc = dt_insert(env, child, (const struct dt_rec *)rec,
-                              (const struct dt_key *)dot, th, BYPASS_CAPA, 1);
+               rec->rec_fid = lfsck_dto2fid(cobj);
+               rc = dt_insert(env, cobj, (const struct dt_rec *)rec,
+                              (const struct dt_key *)dot, th, 1);
                if (rc != 0)
                        GOTO(unlock, rc);
 
                /* 3b. insert dotdot into child dir */
-               rec->rec_fid = lfsck_dto2fid(parent);
-               rc = dt_insert(env, child, (const struct dt_rec *)rec,
-                              (const struct dt_key *)dotdot, th,
-                              BYPASS_CAPA, 1);
+               rec->rec_fid = lfsck_dto2fid(pobj);
+               rc = dt_insert(env, cobj, (const struct dt_rec *)rec,
+                              (const struct dt_key *)dotdot, th, 1);
                if (rc != 0)
                        GOTO(unlock, rc);
 
                /* 4b. increase child nlink */
-               rc = dt_ref_add(env, child, th);
+               rc = dt_ref_add(env, cobj, th);
                if (rc != 0)
                        GOTO(unlock, rc);
 
                /* 5b. generate slave LMV EA. */
                if (lnr->lnr_lmv != NULL && lnr->lnr_lmv->ll_lmv_master) {
-                       rc = dt_xattr_set(env, child, &lmv_buf, XATTR_NAME_LMV,
-                                         0, th, BYPASS_CAPA);
+                       rc = dt_xattr_set(env, cobj, &lmv_buf, XATTR_NAME_LMV,
+                                         0, th);
                        if (rc != 0)
                                GOTO(unlock, rc);
                }
        }
 
        /* 6b. insert linkEA for child. */
-       rc = dt_xattr_set(env, child, &linkea_buf,
-                         XATTR_NAME_LINK, 0, th, BYPASS_CAPA);
+       rc = dt_xattr_set(env, cobj, &linkea_buf,
+                         XATTR_NAME_LINK, 0, th);
 
        GOTO(unlock, rc);
 
 unlock:
-       dt_write_unlock(env, child);
+       dt_write_unlock(env, cobj);
 
 stop:
        dt_trans_stop(env, dev, th);
 
 log:
-       lfsck_ibits_unlock(&lh, LCK_EX);
+       lfsck_unlock(llh);
        CDEBUG(D_LFSCK, "%s: namespace LFSCK assistant found dangling "
               "reference for: parent "DFID", child "DFID", type %u, "
               "name %s. %s: rc = %d\n", lfsck_lfsck2name(lfsck),
               PFID(lfsck_dto2fid(parent)), PFID(lfsck_dto2fid(child)),
               type, cname->ln_name,
-              create ? "Create the lost OST-object as required" :
+              create ? "Create the lost MDT-object as required" :
                        "Keep the MDT-object there by default", rc);
 
        if (rc <= 0) {
@@ -4937,14 +5009,16 @@ static int lfsck_namespace_assistant_handler_p1(const struct lu_env *env,
        struct lfsck_instance      *lfsck    = com->lc_lfsck;
        struct lfsck_bookmark      *bk       = &lfsck->li_bookmark_ram;
        struct lfsck_namespace     *ns       = com->lc_file_ram;
-       struct linkea_data          ldata    = { 0 };
+       struct lfsck_assistant_data *lad     = com->lc_data;
+       struct linkea_data          ldata    = { NULL };
        const struct lu_name       *cname;
        struct thandle             *handle   = NULL;
        struct lfsck_namespace_req *lnr      =
                        container_of0(lar, struct lfsck_namespace_req, lnr_lar);
-       struct dt_object           *dir      = lnr->lnr_obj;
+       struct dt_object           *dir      = NULL;
        struct dt_object           *obj      = NULL;
-       const struct lu_fid        *pfid     = lfsck_dto2fid(dir);
+       struct lfsck_assistant_object *lso   = lar->lar_parent;
+       const struct lu_fid        *pfid     = &lso->lso_fid;
        struct dt_device           *dev      = NULL;
        struct lustre_handle        lh       = { 0 };
        bool                        repaired = false;
@@ -4953,12 +5027,17 @@ static int lfsck_namespace_assistant_handler_p1(const struct lu_env *env,
        bool                        newdata;
        bool                        log      = false;
        bool                        bad_hash = false;
+       bool                        bad_linkea = false;
        int                         idx      = 0;
        int                         count    = 0;
-       int                         rc;
+       int                         rc       = 0;
        enum lfsck_namespace_inconsistency_type type = LNIT_NONE;
        ENTRY;
 
+       if (lso->lso_dead)
+               RETURN(0);
+
+       la->la_nlink = 0;
        if (lnr->lnr_attr & LUDA_UPGRADE) {
                ns->ln_flags |= LF_UPGRADE;
                ns->ln_dirent_repaired++;
@@ -4979,14 +5058,31 @@ static int lfsck_namespace_assistant_handler_p1(const struct lu_env *env,
                GOTO(out, rc);
        }
 
+       if (unlikely(!fid_is_sane(&lnr->lnr_fid))) {
+               CDEBUG(D_LFSCK, "%s: dir scan find invalid FID "DFID
+                      " for the name entry %.*s under "DFID"\n",
+                      lfsck_lfsck2name(lfsck), PFID(&lnr->lnr_fid),
+                      lnr->lnr_namelen, lnr->lnr_name, PFID(pfid));
+
+               if (strcmp(lnr->lnr_name, dotdot) != 0)
+                       /* invalid FID means bad name entry, remove it. */
+                       type = LNIT_BAD_DIRENT;
+               else
+                       /* If the parent FID is invalid, we cannot remove
+                        * the ".." entry directly. */
+                       rc = lfsck_namespace_trace_update(env, com, pfid,
+                                               LNTF_CHECK_PARENT, true);
+
+               GOTO(out, rc);
+       }
+
        if (unlikely(lnr->lnr_dir_cookie == MDS_DIR_END_OFF)) {
                rc = lfsck_namespace_striped_dir_rescan(env, com, lnr);
 
                RETURN(rc);
        }
 
-       if (lnr->lnr_name[0] == '.' &&
-           (lnr->lnr_namelen == 1 || fid_seq_is_dot(fid_seq(&lnr->lnr_fid))))
+       if (fid_seq_is_dot(fid_seq(&lnr->lnr_fid)))
                GOTO(out, rc = 0);
 
        if (lnr->lnr_lmv != NULL && lnr->lnr_lmv->ll_lmv_master) {
@@ -4999,11 +5095,11 @@ static int lfsck_namespace_assistant_handler_p1(const struct lu_env *env,
        if (idx < 0)
                GOTO(out, rc = idx);
 
-       if (idx == lfsck_dev_idx(lfsck->li_bottom)) {
+       if (idx == lfsck_dev_idx(lfsck)) {
                if (unlikely(strcmp(lnr->lnr_name, dotdot) == 0))
                        GOTO(out, rc = 0);
 
-               dev = lfsck->li_next;
+               dev = lfsck->li_bottom;
        } else {
                struct lfsck_tgt_desc *ltd;
 
@@ -5017,7 +5113,7 @@ static int lfsck_namespace_assistant_handler_p1(const struct lu_env *env,
                        GOTO(out, rc);
                }
 
-               ltd = LTD_TGT(&lfsck->li_mdt_descs, idx);
+               ltd = lfsck_ltd2tgt(&lfsck->li_mdt_descs, idx);
                if (unlikely(ltd == NULL)) {
                        CDEBUG(D_LFSCK, "%s: cannot talk with MDT %x which "
                               "did not join the namespace LFSCK\n",
@@ -5038,6 +5134,15 @@ static int lfsck_namespace_assistant_handler_p1(const struct lu_env *env,
        if (dt_object_exists(obj) == 0) {
 
 dangling:
+               if (dir == NULL) {
+                       dir = lfsck_assistant_object_load(env, lfsck, lso);
+                       if (IS_ERR(dir)) {
+                               rc = PTR_ERR(dir);
+
+                               GOTO(trace, rc == -ENOENT ? 0 : rc);
+                       }
+               }
+
                rc = lfsck_namespace_check_exist(env, dir, obj, lnr->lnr_name);
                if (rc == 0) {
                        if (!lfsck_is_valid_slave_name_entry(env, lnr->lnr_lmv,
@@ -5048,7 +5153,7 @@ dangling:
                        }
 
                        type = LNIT_DANGLING;
-                       rc = lfsck_namespace_repair_dangling(env, com,
+                       rc = lfsck_namespace_repair_dangling(env, com, dir,
                                                             obj, lnr);
                        if (rc == 0)
                                repaired = true;
@@ -5057,7 +5162,7 @@ dangling:
                GOTO(out, rc);
        }
 
-       if (!(bk->lb_param & LPF_DRYRUN) && repaired) {
+       if (!(bk->lb_param & LPF_DRYRUN) && lad->lad_advance_lock) {
 
 again:
                rc = lfsck_ibits_lock(env, lfsck, obj, &lh,
@@ -5074,7 +5179,7 @@ again:
                if (rc != 0)
                        GOTO(stop, rc);
 
-               rc = dt_trans_start(env, dev, handle);
+               rc = dt_trans_start_local(env, dev, handle);
                if (rc != 0)
                        GOTO(stop, rc);
 
@@ -5082,10 +5187,6 @@ again:
                dtlocked = true;
        }
 
-       rc = lfsck_namespace_check_exist(env, dir, obj, lnr->lnr_name);
-       if (rc != 0)
-               GOTO(stop, rc);
-
        rc = lfsck_links_read(env, obj, &ldata);
        if (unlikely(rc == -ENOENT)) {
                if (handle != NULL) {
@@ -5112,16 +5213,15 @@ again:
                                type = LNIT_BAD_TYPE;
                        }
 
-                       goto record;
+                       goto stop;
                }
 
-               ns->ln_flags |= LF_INCONSISTENT;
-
                /* If the name entry hash does not match the slave striped
                 * directory, and the name entry does not match also, then
                 * it is quite possible that name entry is corrupted. */
                if (!lfsck_is_valid_slave_name_entry(env, lnr->lnr_lmv,
                                        lnr->lnr_name, lnr->lnr_namelen)) {
+                       ns->ln_flags |= LF_INCONSISTENT;
                        type = LNIT_BAD_DIRENT;
 
                        GOTO(stop, rc = 0);
@@ -5132,6 +5232,7 @@ again:
                 * not recognize the name entry, then it is quite possible
                 * that the name entry is corrupted. */
                if ((lfsck_object_type(obj) & S_IFMT) != lnr->lnr_type) {
+                       ns->ln_flags |= LF_INCONSISTENT;
                        type = LNIT_BAD_DIRENT;
 
                        GOTO(stop, rc = 0);
@@ -5154,7 +5255,6 @@ again:
                        type = LNIT_BAD_TYPE;
 
                count = 1;
-               ns->ln_flags |= LF_INCONSISTENT;
                /* The magic crashed, we are not sure whether there are more
                 * corrupt data in the linkea, so remove all linkea entries. */
                remove = true;
@@ -5165,26 +5265,52 @@ again:
                        type = LNIT_BAD_TYPE;
 
                count = 1;
-               ns->ln_flags |= LF_UPGRADE;
                remove = false;
                newdata = true;
 
 nodata:
                if (bk->lb_param & LPF_DRYRUN) {
+                       if (rc == -ENODATA)
+                               ns->ln_flags |= LF_UPGRADE;
+                       else
+                               ns->ln_flags |= LF_INCONSISTENT;
                        ns->ln_linkea_repaired++;
                        repaired = true;
                        log = true;
-                       goto record;
+                       goto stop;
                }
 
-               if (!lustre_handle_is_used(&lh))
+               if (!lustre_handle_is_used(&lh)) {
+                       remove = false;
+                       newdata = false;
+                       type = LNIT_NONE;
+
                        goto again;
+               }
+
+               if (dir == NULL) {
+                       dir = lfsck_assistant_object_load(env, lfsck, lso);
+                       if (IS_ERR(dir)) {
+                               rc = PTR_ERR(dir);
+
+                               GOTO(stop, rc == -ENOENT ? 0 : rc);
+                       }
+               }
+
+               rc = lfsck_namespace_check_exist(env, dir, obj, lnr->lnr_name);
+               if (rc != 0)
+                       GOTO(stop, rc);
+
+               bad_linkea = true;
+               if (!remove && newdata)
+                       ns->ln_flags |= LF_UPGRADE;
+               else if (remove || !(ns->ln_flags & LF_UPGRADE))
+                       ns->ln_flags |= LF_INCONSISTENT;
 
                if (remove) {
                        LASSERT(newdata);
 
-                       rc = dt_xattr_del(env, obj, XATTR_NAME_LINK, handle,
-                                         BYPASS_CAPA);
+                       rc = dt_xattr_del(env, obj, XATTR_NAME_LINK, handle);
                        if (rc != 0)
                                GOTO(stop, rc);
                }
@@ -5242,35 +5368,6 @@ nodata:
                GOTO(stop, rc);
        }
 
-record:
-       LASSERT(count > 0);
-
-       rc = dt_attr_get(env, obj, la, BYPASS_CAPA);
-       if (rc != 0)
-               GOTO(stop, rc);
-
-       if ((count == 1 && la->la_nlink == 1) ||
-           S_ISDIR(lfsck_object_type(obj)))
-               /* Usually, it is for single linked object or dir, do nothing.*/
-               GOTO(stop, rc);
-
-       /* Following modification will be in another transaction.  */
-       if (handle != NULL) {
-               dt_write_unlock(env, obj);
-               dtlocked = false;
-
-               dt_trans_stop(env, dev, handle);
-               handle = NULL;
-
-               lfsck_ibits_unlock(&lh, LCK_EX);
-       }
-
-       ns->ln_mul_linked_checked++;
-       rc = lfsck_namespace_trace_update(env, com, &lnr->lnr_fid,
-                                         LNTF_CHECK_LINKEA, true);
-
-       GOTO(out, rc);
-
 stop:
        if (dtlocked)
                dt_write_unlock(env, obj);
@@ -5288,13 +5385,31 @@ out:
                ns->ln_flags |= LF_INCONSISTENT;
 
                log = false;
+               if (dir == NULL) {
+                       dir = lfsck_assistant_object_load(env, lfsck, lso);
+                       if (IS_ERR(dir)) {
+                               rc = PTR_ERR(dir);
+
+                               GOTO(trace, rc == -ENOENT ? 0 : rc);
+                       }
+               }
+
                rc = lfsck_namespace_repair_bad_name_hash(env, com, dir,
                                                lnr->lnr_lmv, lnr->lnr_name);
-               if (rc >= 0)
+               if (rc == 0)
                        bad_hash = true;
        }
 
        if (rc >= 0) {
+               if (type != LNIT_NONE && dir == NULL) {
+                       dir = lfsck_assistant_object_load(env, lfsck, lso);
+                       if (IS_ERR(dir)) {
+                               rc = PTR_ERR(dir);
+
+                               GOTO(trace, rc == -ENOENT ? 0 : rc);
+                       }
+               }
+
                switch (type) {
                case LNIT_BAD_TYPE:
                        log = false;
@@ -5319,21 +5434,24 @@ out:
                default:
                        break;
                }
+
+               if (count == 1 && S_ISREG(lfsck_object_type(obj)))
+                       dt_attr_get(env, obj, la);
        }
 
+trace:
        down_write(&com->lc_sem);
        if (rc < 0) {
                CDEBUG(D_LFSCK, "%s: namespace LFSCK assistant fail to handle "
                       "the entry: "DFID", parent "DFID", name %.*s: rc = %d\n",
-                      lfsck_lfsck2name(lfsck), PFID(&lnr->lnr_fid),
-                      PFID(lfsck_dto2fid(lnr->lnr_obj)),
+                      lfsck_lfsck2name(lfsck), PFID(&lnr->lnr_fid), PFID(pfid),
                       lnr->lnr_namelen, lnr->lnr_name, rc);
 
                lfsck_namespace_record_failure(env, lfsck, ns);
                if ((rc == -ENOTCONN || rc == -ESHUTDOWN || rc == -EREMCHG ||
                     rc == -ETIMEDOUT || rc == -EHOSTDOWN ||
                     rc == -EHOSTUNREACH || rc == -EINPROGRESS) &&
-                   dev != NULL && dev != lfsck->li_next)
+                   dev != NULL && dev != lfsck->li_bottom)
                        lfsck_lad_set_bitmap(env, com, idx);
 
                if (!(bk->lb_param & LPF_FAILOUT))
@@ -5343,8 +5461,7 @@ out:
                        CDEBUG(D_LFSCK, "%s: namespace LFSCK assistant "
                               "repaired the entry: "DFID", parent "DFID
                               ", name %.*s\n", lfsck_lfsck2name(lfsck),
-                              PFID(&lnr->lnr_fid),
-                              PFID(lfsck_dto2fid(lnr->lnr_obj)),
+                              PFID(&lnr->lnr_fid), PFID(pfid),
                               lnr->lnr_namelen, lnr->lnr_name);
 
                if (repaired) {
@@ -5385,14 +5502,22 @@ out:
                                               false);
                }
 
-
                rc = 0;
        }
+
+       if (count > 1 || la->la_nlink > 1)
+               ns->ln_mul_linked_checked++;
+
        up_write(&com->lc_sem);
 
        if (obj != NULL && !IS_ERR(obj))
                lfsck_object_put(env, obj);
 
+       if (dir != NULL && !IS_ERR(dir))
+               lfsck_object_put(env, dir);
+
+       lad->lad_advance_lock = bad_linkea;
+
        return rc;
 }
 
@@ -5432,10 +5557,11 @@ static int lfsck_namespace_scan_local_lpf_one(const struct lu_env *env,
        struct lu_fid                   *key    = &info->lti_fid;
        struct lu_attr                  *la     = &info->lti_la;
        struct lfsck_instance           *lfsck  = com->lc_lfsck;
-       struct dt_object                *obj    = com->lc_obj;
+       struct dt_object                *obj;
        struct dt_device                *dev    = lfsck->li_bottom;
        struct dt_object                *child  = NULL;
        struct thandle                  *th     = NULL;
+       int                              idx;
        int                              rc     = 0;
        __u8                             flags  = 0;
        bool                             exist  = false;
@@ -5448,9 +5574,11 @@ static int lfsck_namespace_scan_local_lpf_one(const struct lu_env *env,
        LASSERT(dt_object_exists(child));
        LASSERT(!dt_object_remote(child));
 
+       idx = lfsck_sub_trace_file_fid2idx(&ent->lde_fid);
+       obj = com->lc_sub_trace_objs[idx].lsto_obj;
        fid_cpu_to_be(key, &ent->lde_fid);
        rc = dt_lookup(env, obj, (struct dt_rec *)&flags,
-                      (const struct dt_key *)key, BYPASS_CAPA);
+                      (const struct dt_key *)key);
        if (rc == 0) {
                exist = true;
                flags |= LNTF_CHECK_ORPHAN;
@@ -5504,8 +5632,7 @@ static int lfsck_namespace_scan_local_lpf_one(const struct lu_env *env,
                GOTO(stop, rc);
 
        /* b1. remove name entry from backend /lost+found */
-       rc = dt_delete(env, parent, (const struct dt_key *)ent->lde_name, th,
-                      BYPASS_CAPA);
+       rc = dt_delete(env, parent, (const struct dt_key *)ent->lde_name, th);
        if (rc != 0)
                GOTO(stop, rc);
 
@@ -5520,20 +5647,19 @@ static int lfsck_namespace_scan_local_lpf_one(const struct lu_env *env,
 
        if (exist) {
                /* a3. remove child's FID from the LFSCK trace file. */
-               rc = dt_delete(env, obj, (const struct dt_key *)key, th,
-                              BYPASS_CAPA);
+               rc = dt_delete(env, obj, (const struct dt_key *)key, th);
                if (rc != 0)
                        GOTO(stop, rc);
        } else {
                /* b4. set child's ctime as 1 */
-               rc = dt_attr_set(env, child, la, th, BYPASS_CAPA);
+               rc = dt_attr_set(env, child, la, th);
                if (rc != 0)
                        GOTO(stop, rc);
        }
 
        /* b5. insert child's FID into the LFSCK trace file. */
        rc = dt_insert(env, obj, (const struct dt_rec *)&flags,
-                      (const struct dt_key *)key, th, BYPASS_CAPA, 1);
+                      (const struct dt_key *)key, th, 1);
 
        GOTO(stop, rc = (rc == 0 ? 1 : rc));
 
@@ -5541,7 +5667,7 @@ stop:
        dt_trans_stop(env, dev, th);
 
 out:
-       lu_object_put(env, &child->do_lu);
+       lfsck_object_put(env, child);
 
        return rc;
 }
@@ -5571,19 +5697,19 @@ static void lfsck_namespace_scan_local_lpf(const struct lu_env *env,
        struct lfsck_instance           *lfsck  = com->lc_lfsck;
        struct ptlrpc_thread            *thread = &lfsck->li_thread;
        struct lfsck_bookmark           *bk     = &lfsck->li_bookmark_ram;
-       struct dt_device                *dev    = lfsck->li_bottom;
        struct lfsck_namespace          *ns     = com->lc_file_ram;
        struct dt_object                *parent;
        const struct dt_it_ops          *iops;
        struct dt_it                    *di;
-       struct seq_server_site          *ss     =
-                                       lu_site2seq(dev->dd_lu_dev.ld_site);
+       struct seq_server_site          *ss     = lfsck_dev_site(lfsck);
        __u64                            cookie;
+       __u32                            idx    = lfsck_dev_idx(lfsck);
        int                              rc     = 0;
        __u16                            type;
        ENTRY;
 
-       parent = lfsck_object_find_by_dev(env, dev, &LU_BACKEND_LPF_FID);
+       parent = lfsck_object_find_by_dev(env, lfsck->li_bottom,
+                                         &LU_BACKEND_LPF_FID);
        if (IS_ERR(parent)) {
                CERROR("%s: fail to find backend /lost+found: rc = %ld\n",
                       lfsck_lfsck2name(lfsck), PTR_ERR(parent));
@@ -5602,7 +5728,7 @@ static void lfsck_namespace_scan_local_lpf(const struct lu_env *env,
 
        com->lc_new_scanned = 0;
        iops = &parent->do_index_ops->dio_it;
-       di = iops->init(env, parent, LUDA_64BITHASH | LUDA_TYPE, BYPASS_CAPA);
+       di = iops->init(env, parent, LUDA_64BITHASH | LUDA_TYPE);
        if (IS_ERR(di))
                GOTO(out, rc = PTR_ERR(di));
 
@@ -5613,19 +5739,9 @@ static void lfsck_namespace_scan_local_lpf(const struct lu_env *env,
                rc = 0;
 
        while (rc == 0) {
-               if (OBD_FAIL_CHECK(OBD_FAIL_LFSCK_DELAY3) &&
-                   cfs_fail_val > 0) {
-                       struct l_wait_info lwi;
-
-                       lwi = LWI_TIMEOUT(cfs_time_seconds(cfs_fail_val),
-                                         NULL, NULL);
-                       l_wait_event(thread->t_ctl_waitq,
-                                    !thread_is_running(thread),
-                                    &lwi);
-
-                       if (unlikely(!thread_is_running(thread)))
-                               break;
-               }
+               if (CFS_FAIL_TIMEOUT(OBD_FAIL_LFSCK_DELAY3, cfs_fail_val) &&
+                   unlikely(!thread_is_running(thread)))
+                       break;
 
                rc = iops->rec(env, di, (struct dt_rec *)ent,
                               LUDA_64BITHASH | LUDA_TYPE);
@@ -5653,7 +5769,7 @@ static void lfsck_namespace_scan_local_lpf(const struct lu_env *env,
                                              fid_seq(&ent->lde_fid), range);
                        if (rc != 0)
                                goto skip;
-               } else if (lfsck_dev_idx(dev) != 0) {
+               } else if (idx != 0) {
                        /* If the returned FID is IGIF, then there are three
                         * possible cases:
                         *
@@ -5678,8 +5794,7 @@ static void lfsck_namespace_scan_local_lpf(const struct lu_env *env,
                               "in the backend /lost+found on the MDT %04x, "
                               "to be safe, skip it.\n",
                               lfsck_lfsck2name(lfsck), ent->lde_namelen,
-                              ent->lde_name, PFID(&ent->lde_fid),
-                              lfsck_dev_idx(dev));
+                              ent->lde_name, PFID(&ent->lde_fid), idx);
                        goto skip;
                }
 
@@ -5719,7 +5834,7 @@ out:
        CDEBUG(D_LFSCK, "%s: stop to scan backend /lost+found: rc = %d\n",
               lfsck_lfsck2name(lfsck), rc);
 
-       lu_object_put(env, &parent->do_lu);
+       lfsck_object_put(env, parent);
 }
 
 /**
@@ -5756,6 +5871,7 @@ static int lfsck_namespace_rescan_striped_dir(const struct lu_env *env,
                        (struct lu_dirent *)info->lti_key;
        struct lfsck_bookmark           *bk     = &lfsck->li_bookmark_ram;
        struct ptlrpc_thread            *thread = &lfsck->li_thread;
+       struct lfsck_assistant_object   *lso    = NULL;
        struct lfsck_namespace_req      *lnr;
        struct lfsck_assistant_req      *lar;
        int                              rc;
@@ -5790,7 +5906,20 @@ static int lfsck_namespace_rescan_striped_dir(const struct lu_env *env,
                if (name_is_dot_or_dotdot(ent->lde_name, ent->lde_namelen))
                        goto next;
 
-               lnr = lfsck_namespace_assistant_req_init(lfsck, ent, type);
+               if (lso == NULL) {
+                       lso = lfsck_assistant_object_init(env,
+                               lfsck_dto2fid(dir), NULL,
+                               lfsck->li_pos_current.lp_oit_cookie, true);
+                       if (IS_ERR(lso)) {
+                               if (bk->lb_param & LPF_FAILOUT)
+                                       GOTO(out, rc = PTR_ERR(lso));
+
+                               lso = NULL;
+                               goto next;
+                       }
+               }
+
+               lnr = lfsck_namespace_assistant_req_init(lfsck, lso, ent, type);
                if (IS_ERR(lnr)) {
                        if (bk->lb_param & LPF_FAILOUT)
                                GOTO(out, rc = PTR_ERR(lnr));
@@ -5812,6 +5941,9 @@ next:
        } while (rc == 0);
 
 out:
+       if (lso != NULL && !IS_ERR(lso))
+               lfsck_assistant_object_put(env, lso);
+
        lfsck_close_dir(env, lfsck, rc);
        if (rc <= 0)
                RETURN(rc);
@@ -5832,14 +5964,15 @@ out:
        RETURN(rc == 0 ? 1 : rc);
 }
 
-static int lfsck_namespace_assistant_handler_p2(const struct lu_env *env,
-                                               struct lfsck_component *com)
+static int
+lfsck_namespace_double_scan_one_trace_file(const struct lu_env *env,
+                                          struct lfsck_component *com,
+                                          struct dt_object *obj, bool first)
 {
        struct lfsck_instance   *lfsck  = com->lc_lfsck;
        struct ptlrpc_thread    *thread = &lfsck->li_thread;
        struct lfsck_bookmark   *bk     = &lfsck->li_bookmark_ram;
        struct lfsck_namespace  *ns     = com->lc_file_ram;
-       struct dt_object        *obj    = com->lc_obj;
        const struct dt_it_ops  *iops   = &obj->do_index_ops->dio_it;
        struct dt_object        *target;
        struct dt_it            *di;
@@ -5849,68 +5982,47 @@ static int lfsck_namespace_assistant_handler_p2(const struct lu_env *env,
        __u8                     flags  = 0;
        ENTRY;
 
-       while (!list_empty(&lfsck->li_list_lmv)) {
-               struct lfsck_lmv_unit *llu;
-
-               spin_lock(&lfsck->li_lock);
-               llu = list_entry(lfsck->li_list_lmv.next,
-                                struct lfsck_lmv_unit, llu_link);
-               list_del_init(&llu->llu_link);
-               spin_unlock(&lfsck->li_lock);
-
-               rc = lfsck_namespace_rescan_striped_dir(env, com, llu);
-               if (rc <= 0)
-                       RETURN(rc);
-       }
-
-       CDEBUG(D_LFSCK, "%s: namespace LFSCK phase2 scan start\n",
-              lfsck_lfsck2name(lfsck));
-
-       lfsck_namespace_scan_local_lpf(env, com);
-
-       com->lc_new_checked = 0;
-       com->lc_new_scanned = 0;
-       com->lc_time_last_checkpoint = cfs_time_current();
-       com->lc_time_next_checkpoint = com->lc_time_last_checkpoint +
-                               cfs_time_seconds(LFSCK_CHECKPOINT_INTERVAL);
-
-       di = iops->init(env, obj, 0, BYPASS_CAPA);
+       di = iops->init(env, obj, 0);
        if (IS_ERR(di))
                RETURN(PTR_ERR(di));
 
-       fid_cpu_to_be(&fid, &ns->ln_fid_latest_scanned_phase2);
+       if (first)
+               fid_cpu_to_be(&fid, &ns->ln_fid_latest_scanned_phase2);
+       else
+               fid_zero(&fid);
        rc = iops->get(env, di, (const struct dt_key *)&fid);
        if (rc < 0)
                GOTO(fini, rc);
 
-       /* Skip the start one, which either has been processed or non-exist. */
-       rc = iops->next(env, di);
-       if (rc != 0)
-               GOTO(put, rc);
+       if (first) {
+               /* The start one either has been processed or does not exist,
+                * skip it. */
+               rc = iops->next(env, di);
+               if (rc != 0)
+                       GOTO(put, rc);
+       }
 
        do {
-               if (OBD_FAIL_CHECK(OBD_FAIL_LFSCK_DELAY3) &&
-                   cfs_fail_val > 0) {
-                       struct l_wait_info lwi;
-
-                       lwi = LWI_TIMEOUT(cfs_time_seconds(cfs_fail_val),
-                                         NULL, NULL);
-                       l_wait_event(thread->t_ctl_waitq,
-                                    !thread_is_running(thread),
-                                    &lwi);
-
-                       if (unlikely(!thread_is_running(thread)))
-                               GOTO(put, rc = 0);
-               }
+               if (CFS_FAIL_TIMEOUT(OBD_FAIL_LFSCK_DELAY3, cfs_fail_val) &&
+                   unlikely(!thread_is_running(thread)))
+                       GOTO(put, rc = 0);
 
                key = iops->key(env, di);
+               if (IS_ERR(key)) {
+                       rc = PTR_ERR(key);
+                       if (rc == -ENOENT)
+                               GOTO(put, rc = 1);
+
+                       goto checkpoint;
+               }
+
                fid_be_to_cpu(&fid, (const struct lu_fid *)key);
                if (!fid_is_sane(&fid)) {
                        rc = 0;
                        goto checkpoint;
                }
 
-               target = lfsck_object_find_by_dev(env, lfsck->li_bottom, &fid);
+               target = lfsck_object_find_bottom(env, lfsck, &fid);
                if (IS_ERR(target)) {
                        rc = PTR_ERR(target);
                        goto checkpoint;
@@ -5932,7 +6044,8 @@ checkpoint:
                down_write(&com->lc_sem);
                com->lc_new_checked++;
                com->lc_new_scanned++;
-               ns->ln_fid_latest_scanned_phase2 = fid;
+               if (rc >= 0 && fid_is_sane(&fid))
+                       ns->ln_fid_latest_scanned_phase2 = fid;
                if (rc > 0)
                        ns->ln_objs_repaired_phase2++;
                else if (rc < 0)
@@ -5952,7 +6065,7 @@ checkpoint:
                        ns->ln_time_last_checkpoint = cfs_time_current_sec();
                        ns->ln_objs_checked_phase2 += com->lc_new_checked;
                        com->lc_new_checked = 0;
-                       rc = lfsck_namespace_store(env, com);
+                       rc = lfsck_namespace_store(env, com, false);
                        up_write(&com->lc_sem);
                        if (rc != 0)
                                GOTO(put, rc);
@@ -5978,12 +6091,56 @@ put:
 fini:
        iops->fini(env, di);
 
-       CDEBUG(D_LFSCK, "%s: namespace LFSCK phase2 scan stop: rc = %d\n",
-              lfsck_lfsck2name(lfsck), rc);
-
        return rc;
 }
 
+static int lfsck_namespace_assistant_handler_p2(const struct lu_env *env,
+                                               struct lfsck_component *com)
+{
+       struct lfsck_instance   *lfsck  = com->lc_lfsck;
+       struct lfsck_namespace  *ns     = com->lc_file_ram;
+       int                      rc;
+       int                      i;
+       ENTRY;
+
+       while (!list_empty(&lfsck->li_list_lmv)) {
+               struct lfsck_lmv_unit *llu;
+
+               spin_lock(&lfsck->li_lock);
+               llu = list_entry(lfsck->li_list_lmv.next,
+                                struct lfsck_lmv_unit, llu_link);
+               list_del_init(&llu->llu_link);
+               spin_unlock(&lfsck->li_lock);
+
+               rc = lfsck_namespace_rescan_striped_dir(env, com, llu);
+               if (rc <= 0)
+                       RETURN(rc);
+       }
+
+       CDEBUG(D_LFSCK, "%s: namespace LFSCK phase2 scan start\n",
+              lfsck_lfsck2name(lfsck));
+
+       lfsck_namespace_scan_local_lpf(env, com);
+
+       com->lc_new_checked = 0;
+       com->lc_new_scanned = 0;
+       com->lc_time_last_checkpoint = cfs_time_current();
+       com->lc_time_next_checkpoint = com->lc_time_last_checkpoint +
+                               cfs_time_seconds(LFSCK_CHECKPOINT_INTERVAL);
+
+       i = lfsck_sub_trace_file_fid2idx(&ns->ln_fid_latest_scanned_phase2);
+       rc = lfsck_namespace_double_scan_one_trace_file(env, com,
+                               com->lc_sub_trace_objs[i].lsto_obj, true);
+       while (rc > 0 && ++i < LFSCK_STF_COUNT)
+               rc = lfsck_namespace_double_scan_one_trace_file(env, com,
+                               com->lc_sub_trace_objs[i].lsto_obj, false);
+
+       CDEBUG(D_LFSCK, "%s: namespace LFSCK phase2 scan stop at the No. %d "
+              "trace file: rc = %d\n", lfsck_lfsck2name(lfsck), i, rc);
+
+       RETURN(rc);
+}
+
 static void lfsck_namespace_assistant_fill_pos(const struct lu_env *env,
                                               struct lfsck_component *com,
                                               struct lfsck_position *pos)
@@ -5997,9 +6154,9 @@ static void lfsck_namespace_assistant_fill_pos(const struct lu_env *env,
        lnr = list_entry(lad->lad_req_list.next,
                         struct lfsck_namespace_req,
                         lnr_lar.lar_list);
-       pos->lp_oit_cookie = lnr->lnr_oit_cookie;
+       pos->lp_oit_cookie = lnr->lnr_lar.lar_parent->lso_oit_cookie;
        pos->lp_dir_cookie = lnr->lnr_dir_cookie - 1;
-       pos->lp_dir_parent = *lfsck_dto2fid(lnr->lnr_obj);
+       pos->lp_dir_parent = lnr->lnr_lar.lar_parent->lso_fid;
 }
 
 static int lfsck_namespace_double_scan_result(const struct lu_env *env,
@@ -6011,7 +6168,7 @@ static int lfsck_namespace_double_scan_result(const struct lu_env *env,
 
        down_write(&com->lc_sem);
        ns->ln_run_time_phase2 += cfs_duration_sec(cfs_time_current() +
-                               HALF_SEC - lfsck->li_time_last_checkpoint);
+                                 HALF_SEC - com->lc_time_last_checkpoint);
        ns->ln_time_last_checkpoint = cfs_time_current_sec();
        ns->ln_objs_checked_phase2 += com->lc_new_checked;
        com->lc_new_checked = 0;
@@ -6034,7 +6191,7 @@ static int lfsck_namespace_double_scan_result(const struct lu_env *env,
                ns->ln_status = LS_FAILED;
        }
 
-       rc = lfsck_namespace_store(env, com);
+       rc = lfsck_namespace_store(env, com, false);
        up_write(&com->lc_sem);
 
        return rc;
@@ -6045,6 +6202,13 @@ lfsck_namespace_assistant_sync_failures_interpret(const struct lu_env *env,
                                                  struct ptlrpc_request *req,
                                                  void *args, int rc)
 {
+       if (rc == 0) {
+               struct lfsck_async_interpret_args *laia = args;
+               struct lfsck_tgt_desc             *ltd  = laia->laia_ltd;
+
+               ltd->ltd_synced_failures = 1;
+       }
+
        return 0;
 }
 
@@ -6081,9 +6245,13 @@ static void lfsck_namespace_assistant_sync_failures(const struct lu_env *env,
        struct lfsck_tgt_descs            *ltds  = &lfsck->li_mdt_descs;
        struct lfsck_tgt_desc             *ltd;
        struct ptlrpc_request_set         *set;
+       __u32                              idx;
        int                                rc    = 0;
        ENTRY;
 
+       if (!lad->lad_incomplete)
+               RETURN_EXIT;
+
        set = ptlrpc_prep_set();
        if (set == NULL)
                GOTO(out, rc = -ENOMEM);
@@ -6092,25 +6260,12 @@ static void lfsck_namespace_assistant_sync_failures(const struct lu_env *env,
        memset(laia, 0, sizeof(*laia));
        lad->lad_touch_gen++;
 
-       spin_lock(&ltds->ltd_lock);
-       while (!list_empty(&lad->lad_mdt_list)) {
-               ltd = list_entry(lad->lad_mdt_list.next,
-                                struct lfsck_tgt_desc,
-                                ltd_namespace_list);
-               if (ltd->ltd_namespace_gen == lad->lad_touch_gen)
-                       break;
-
-               ltd->ltd_namespace_gen = lad->lad_touch_gen;
-               list_move_tail(&ltd->ltd_namespace_list,
-                              &lad->lad_mdt_list);
-               if (!lad->lad_incomplete ||
-                   !cfs_bitmap_check(lad->lad_bitmap, ltd->ltd_index)) {
-                       ltd->ltd_namespace_failed = 0;
-                       continue;
-               }
+       down_read(&ltds->ltd_rw_sem);
+       cfs_foreach_bit(lad->lad_bitmap, idx) {
+               ltd = lfsck_ltd2tgt(ltds, idx);
+               LASSERT(ltd != NULL);
 
-               ltd->ltd_namespace_failed = 1;
-               spin_unlock(&ltds->ltd_lock);
+               laia->laia_ltd = ltd;
                rc = lfsck_async_request(env, ltd->ltd_exp, lr, set,
                        lfsck_namespace_assistant_sync_failures_interpret,
                        laia, LFSCK_NOTIFY);
@@ -6118,10 +6273,8 @@ static void lfsck_namespace_assistant_sync_failures(const struct lu_env *env,
                        CDEBUG(D_LFSCK, "%s: namespace LFSCK assistant fail "
                               "to sync failure with MDT %x: rc = %d\n",
                               lfsck_lfsck2name(lfsck), ltd->ltd_index, rc);
-
-               spin_lock(&ltds->ltd_lock);
        }
-       spin_unlock(&ltds->ltd_lock);
+       up_read(&ltds->ltd_rw_sem);
 
        rc = ptlrpc_set_wait(set);
        ptlrpc_set_destroy(set);
@@ -6153,7 +6306,6 @@ struct lfsck_assistant_operations lfsck_namespace_assistant_ops = {
  * entries, then re-generate the linkEA with the given information.
  *
  * \param[in] env      pointer to the thread context
- * \param[in] dev      pointer to the dt_device
  * \param[in] obj      pointer to the dt_object to be handled
  * \param[in] cname    the name for the child in the parent directory
  * \param[in] pfid     the parent directory's FID for the linkEA
@@ -6161,11 +6313,11 @@ struct lfsck_assistant_operations lfsck_namespace_assistant_ops = {
  * \retval             0 for success
  * \retval             negative error number on failure
  */
-int lfsck_verify_linkea(const struct lu_env *env, struct dt_device *dev,
-                       struct dt_object *obj, const struct lu_name *cname,
-                       const struct lu_fid *pfid)
+int lfsck_verify_linkea(const struct lu_env *env, struct dt_object *obj,
+                       const struct lu_name *cname, const struct lu_fid *pfid)
 {
-       struct linkea_data       ldata  = { 0 };
+       struct dt_device        *dev    = lfsck_obj2dev(obj);
+       struct linkea_data       ldata  = { NULL };
        struct lu_buf            linkea_buf;
        struct thandle          *th;
        int                      rc;
@@ -6217,7 +6369,7 @@ int lfsck_verify_linkea(const struct lu_env *env, struct dt_device *dev,
 
        dt_write_lock(env, obj, 0);
        rc = dt_xattr_set(env, obj, &linkea_buf,
-                         XATTR_NAME_LINK, fl, th, BYPASS_CAPA);
+                         XATTR_NAME_LINK, fl, th);
        dt_write_unlock(env, obj);
 
        GOTO(stop, rc);
@@ -6244,7 +6396,7 @@ int lfsck_links_get_first(const struct lu_env *env, struct dt_object *obj,
                          char *name, struct lu_fid *pfid)
 {
        struct lu_name           *cname = &lfsck_env_info(env)->lti_name;
-       struct linkea_data        ldata = { 0 };
+       struct linkea_data        ldata = { NULL };
        int                       rc;
 
        rc = lfsck_links_read(env, obj, &ldata);
@@ -6264,90 +6416,14 @@ int lfsck_links_get_first(const struct lu_env *env, struct dt_object *obj,
 }
 
 /**
- * Remove the name entry from the parent directory.
- *
- * No need to care about the object referenced by the name entry,
- * either the name entry is invalid or redundant, or the referenced
- * object has been processed has been or will be handled by others.
- *
- * \param[in] env      pointer to the thread context
- * \param[in] lfsck    pointer to the lfsck instance
- * \param[in] parent   pointer to the lost+found object
- * \param[in] name     the name for the name entry to be removed
- * \param[in] type     the type for the name entry to be removed
- *
- * \retval             0 for success
- * \retval             negative error number on failure
- */
-int lfsck_remove_name_entry(const struct lu_env *env,
-                           struct lfsck_instance *lfsck,
-                           struct dt_object *parent,
-                           const char *name, __u32 type)
-{
-       struct dt_device        *dev    = lfsck->li_next;
-       struct thandle          *th;
-       struct lustre_handle     lh     = { 0 };
-       int                      rc;
-       ENTRY;
-
-       rc = lfsck_ibits_lock(env, lfsck, parent, &lh,
-                             MDS_INODELOCK_UPDATE, LCK_EX);
-       if (rc != 0)
-               RETURN(rc);
-
-       th = dt_trans_create(env, dev);
-       if (IS_ERR(th))
-               GOTO(unlock, rc = PTR_ERR(th));
-
-       rc = dt_declare_delete(env, parent, (const struct dt_key *)name, th);
-       if (rc != 0)
-               GOTO(stop, rc);
-
-       if (S_ISDIR(type)) {
-               rc = dt_declare_ref_del(env, parent, th);
-               if (rc != 0)
-                       GOTO(stop, rc);
-       }
-
-       rc = dt_trans_start(env, dev, th);
-       if (rc != 0)
-               GOTO(stop, rc);
-
-       rc = dt_delete(env, parent, (const struct dt_key *)name, th,
-                      BYPASS_CAPA);
-       if (rc != 0)
-               GOTO(stop, rc);
-
-       if (S_ISDIR(type)) {
-               dt_write_lock(env, parent, 0);
-               rc = dt_ref_del(env, parent, th);
-               dt_write_unlock(env, parent);
-       }
-
-       GOTO(stop, rc);
-
-stop:
-       dt_trans_stop(env, dev, th);
-
-unlock:
-       lfsck_ibits_unlock(&lh, LCK_EX);
-
-       CDEBUG(D_LFSCK, "%s: remove name entry "DFID"/%s "
-              "with type %o: rc = %d\n", lfsck_lfsck2name(lfsck),
-              PFID(lfsck_dto2fid(parent)), name, type, rc);
-
-       return rc;
-}
-
-/**
  * Update the object's name entry with the given FID.
  *
  * \param[in] env      pointer to the thread context
  * \param[in] lfsck    pointer to the lfsck instance
- * \param[in] parent   pointer to the parent directory that holds
+ * \param[in] dir      pointer to the directory that holds
  *                     the name entry
  * \param[in] name     the name for the entry to be updated
- * \param[in] pfid     the new PFID for the name entry
+ * \param[in] fid      the new FID for the name entry referenced
  * \param[in] type     the type for the name entry to be updated
  *
  * \retval             0 for success
@@ -6355,19 +6431,20 @@ unlock:
  */
 int lfsck_update_name_entry(const struct lu_env *env,
                            struct lfsck_instance *lfsck,
-                           struct dt_object *parent, const char *name,
-                           const struct lu_fid *pfid, __u32 type)
+                           struct dt_object *dir, const char *name,
+                           const struct lu_fid *fid, __u32 type)
 {
-       struct dt_insert_rec    *rec    = &lfsck_env_info(env)->lti_dt_rec;
-       struct dt_device        *dev    = lfsck->li_next;
-       struct lustre_handle     lh     = { 0 };
-       struct thandle          *th;
-       int                      rc;
-       bool                     exists = true;
+       struct lfsck_thread_info *info   = lfsck_env_info(env);
+       struct dt_insert_rec     *rec    = &info->lti_dt_rec;
+       struct lfsck_lock_handle *llh    = &info->lti_llh;
+       struct dt_device         *dev    = lfsck_obj2dev(dir);
+       struct thandle           *th;
+       int                       rc;
+       bool                      exists = true;
        ENTRY;
 
-       rc = lfsck_ibits_lock(env, lfsck, parent, &lh,
-                             MDS_INODELOCK_UPDATE, LCK_EX);
+       rc = lfsck_lock(env, lfsck, dir, name, llh,
+                       MDS_INODELOCK_UPDATE, LCK_PW);
        if (rc != 0)
                RETURN(rc);
 
@@ -6375,27 +6452,26 @@ int lfsck_update_name_entry(const struct lu_env *env,
        if (IS_ERR(th))
                GOTO(unlock, rc = PTR_ERR(th));
 
-       rc = dt_declare_delete(env, parent, (const struct dt_key *)name, th);
+       rc = dt_declare_delete(env, dir, (const struct dt_key *)name, th);
        if (rc != 0)
                GOTO(stop, rc);
 
        rec->rec_type = type;
-       rec->rec_fid = pfid;
-       rc = dt_declare_insert(env, parent, (const struct dt_rec *)rec,
+       rec->rec_fid = fid;
+       rc = dt_declare_insert(env, dir, (const struct dt_rec *)rec,
                               (const struct dt_key *)name, th);
        if (rc != 0)
                GOTO(stop, rc);
 
-       rc = dt_declare_ref_add(env, parent, th);
+       rc = dt_declare_ref_add(env, dir, th);
        if (rc != 0)
                GOTO(stop, rc);
 
-       rc = dt_trans_start(env, dev, th);
+       rc = dt_trans_start_local(env, dev, th);
        if (rc != 0)
                GOTO(stop, rc);
 
-       rc = dt_delete(env, parent, (const struct dt_key *)name, th,
-                      BYPASS_CAPA);
+       rc = dt_delete(env, dir, (const struct dt_key *)name, th);
        if (rc == -ENOENT) {
                exists = false;
                rc = 0;
@@ -6404,12 +6480,12 @@ int lfsck_update_name_entry(const struct lu_env *env,
        if (rc != 0)
                GOTO(stop, rc);
 
-       rc = dt_insert(env, parent, (const struct dt_rec *)rec,
-                      (const struct dt_key *)name, th, BYPASS_CAPA, 1);
+       rc = dt_insert(env, dir, (const struct dt_rec *)rec,
+                      (const struct dt_key *)name, th, 1);
        if (rc == 0 && S_ISDIR(type) && !exists) {
-               dt_write_lock(env, parent, 0);
-               rc = dt_ref_add(env, parent, th);
-               dt_write_unlock(env, parent);
+               dt_write_lock(env, dir, 0);
+               rc = dt_ref_add(env, dir, th);
+               dt_write_unlock(env, dir);
        }
 
        GOTO(stop, rc);
@@ -6418,11 +6494,10 @@ stop:
        dt_trans_stop(env, dev, th);
 
 unlock:
-       lfsck_ibits_unlock(&lh, LCK_EX);
-
+       lfsck_unlock(llh);
        CDEBUG(D_LFSCK, "%s: update name entry "DFID"/%s with the FID "DFID
               " and the type %o: rc = %d\n", lfsck_lfsck2name(lfsck),
-              PFID(lfsck_dto2fid(parent)), name, PFID(pfid), type, rc);
+              PFID(lfsck_dto2fid(dir)), name, PFID(fid), type, rc);
 
        return rc;
 }
@@ -6434,6 +6509,7 @@ int lfsck_namespace_setup(const struct lu_env *env,
        struct lfsck_namespace  *ns;
        struct dt_object        *root = NULL;
        struct dt_object        *obj;
+       int                      i;
        int                      rc;
        ENTRY;
 
@@ -6452,7 +6528,7 @@ int lfsck_namespace_setup(const struct lu_env *env,
        com->lc_ops = &lfsck_namespace_ops;
        com->lc_data = lfsck_assistant_data_init(
                        &lfsck_namespace_assistant_ops,
-                       "lfsck_namespace");
+                       LFSCK_NAMESPACE);
        if (com->lc_data == NULL)
                GOTO(out, rc = -ENOMEM);
 
@@ -6465,6 +6541,9 @@ int lfsck_namespace_setup(const struct lu_env *env,
        if (com->lc_file_disk == NULL)
                GOTO(out, rc = -ENOMEM);
 
+       for (i = 0; i < LFSCK_STF_COUNT; i++)
+               mutex_init(&com->lc_sub_trace_objs[i].lsto_mutex);
+
        root = dt_locate(env, lfsck->li_bottom, &lfsck->li_local_root_fid);
        if (IS_ERR(root))
                GOTO(out, rc = PTR_ERR(root));
@@ -6473,22 +6552,20 @@ int lfsck_namespace_setup(const struct lu_env *env,
                GOTO(out, rc = -ENOTDIR);
 
        obj = local_index_find_or_create(env, lfsck->li_los, root,
-                                        lfsck_namespace_name,
+                                        LFSCK_NAMESPACE,
                                         S_IFREG | S_IRUGO | S_IWUSR,
                                         &dt_lfsck_features);
        if (IS_ERR(obj))
                GOTO(out, rc = PTR_ERR(obj));
 
        com->lc_obj = obj;
-       rc = obj->do_ops->do_index_try(env, obj, &dt_lfsck_features);
-       if (rc != 0)
-               GOTO(out, rc);
-
        rc = lfsck_namespace_load(env, com);
-       if (rc > 0)
-               rc = lfsck_namespace_reset(env, com, true);
-       else if (rc == -ENODATA)
+       if (rc == -ENODATA)
                rc = lfsck_namespace_init(env, com);
+       else if (rc < 0)
+               rc = lfsck_namespace_reset(env, com, true);
+       else
+               rc = lfsck_namespace_load_sub_trace_files(env, com, false);
        if (rc != 0)
                GOTO(out, rc);
 
@@ -6526,7 +6603,7 @@ int lfsck_namespace_setup(const struct lu_env *env,
 
 out:
        if (root != NULL && !IS_ERR(root))
-               lu_object_put(env, &root->do_lu);
+               lfsck_object_put(env, root);
        if (rc != 0) {
                lfsck_component_cleanup(env, com);
                CERROR("%s: fail to init namespace LFSCK component: rc = %d\n",