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LU-5707 lfsck: store namespace LFSCK statistics info in new EA
[fs/lustre-release.git] / lustre / lfsck / lfsck_namespace.c
index f91bdcd..9b67144 100644 (file)
@@ -64,8 +64,8 @@ lfsck_namespace_assistant_req_init(struct lfsck_instance *lfsck,
                return ERR_PTR(-ENOMEM);
 
        INIT_LIST_HEAD(&lnr->lnr_lar.lar_list);
-       lu_object_get(&lfsck->li_obj_dir->do_lu);
-       lnr->lnr_obj = lfsck->li_obj_dir;
+       lnr->lnr_obj = lfsck_object_get(lfsck->li_obj_dir);
+       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;
@@ -84,6 +84,9 @@ static void lfsck_namespace_assistant_req_fini(const struct lu_env *env,
        struct lfsck_namespace_req *lnr =
                        container_of0(lar, struct lfsck_namespace_req, lnr_lar);
 
+       if (lnr->lnr_lmv != NULL)
+               lfsck_lmv_put(env, lnr->lnr_lmv);
+
        lu_object_put(env, &lnr->lnr_obj->do_lu);
        OBD_FREE(lnr, lnr->lnr_size);
 }
@@ -131,6 +134,29 @@ static void lfsck_namespace_le_to_cpu(struct lfsck_namespace *dst,
        dst->ln_bad_type_repaired = le64_to_cpu(src->ln_bad_type_repaired);
        dst->ln_lost_dirent_repaired =
                                le64_to_cpu(src->ln_lost_dirent_repaired);
+       dst->ln_striped_dirs_scanned =
+                               le64_to_cpu(src->ln_striped_dirs_scanned);
+       dst->ln_striped_dirs_repaired =
+                               le64_to_cpu(src->ln_striped_dirs_repaired);
+       dst->ln_striped_dirs_failed =
+                               le64_to_cpu(src->ln_striped_dirs_failed);
+       dst->ln_striped_dirs_disabled =
+                               le64_to_cpu(src->ln_striped_dirs_disabled);
+       dst->ln_striped_dirs_skipped =
+                               le64_to_cpu(src->ln_striped_dirs_skipped);
+       dst->ln_striped_shards_scanned =
+                               le64_to_cpu(src->ln_striped_shards_scanned);
+       dst->ln_striped_shards_repaired =
+                               le64_to_cpu(src->ln_striped_shards_repaired);
+       dst->ln_striped_shards_failed =
+                               le64_to_cpu(src->ln_striped_shards_failed);
+       dst->ln_striped_shards_skipped =
+                               le64_to_cpu(src->ln_striped_shards_skipped);
+       dst->ln_name_hash_repaired = le64_to_cpu(src->ln_name_hash_repaired);
+       dst->ln_local_lpf_scanned = le64_to_cpu(src->ln_local_lpf_scanned);
+       dst->ln_local_lpf_moved = le64_to_cpu(src->ln_local_lpf_moved);
+       dst->ln_local_lpf_skipped = le64_to_cpu(src->ln_local_lpf_skipped);
+       dst->ln_local_lpf_failed = le64_to_cpu(src->ln_local_lpf_failed);
        dst->ln_bitmap_size = le32_to_cpu(src->ln_bitmap_size);
 }
 
@@ -177,6 +203,29 @@ static void lfsck_namespace_cpu_to_le(struct lfsck_namespace *dst,
        dst->ln_bad_type_repaired = cpu_to_le64(src->ln_bad_type_repaired);
        dst->ln_lost_dirent_repaired =
                                cpu_to_le64(src->ln_lost_dirent_repaired);
+       dst->ln_striped_dirs_scanned =
+                               cpu_to_le64(src->ln_striped_dirs_scanned);
+       dst->ln_striped_dirs_repaired =
+                               cpu_to_le64(src->ln_striped_dirs_repaired);
+       dst->ln_striped_dirs_failed =
+                               cpu_to_le64(src->ln_striped_dirs_failed);
+       dst->ln_striped_dirs_disabled =
+                               cpu_to_le64(src->ln_striped_dirs_disabled);
+       dst->ln_striped_dirs_skipped =
+                               cpu_to_le64(src->ln_striped_dirs_skipped);
+       dst->ln_striped_shards_scanned =
+                               cpu_to_le64(src->ln_striped_shards_scanned);
+       dst->ln_striped_shards_repaired =
+                               cpu_to_le64(src->ln_striped_shards_repaired);
+       dst->ln_striped_shards_failed =
+                               cpu_to_le64(src->ln_striped_shards_failed);
+       dst->ln_striped_shards_skipped =
+                               cpu_to_le64(src->ln_striped_shards_skipped);
+       dst->ln_name_hash_repaired = cpu_to_le64(src->ln_name_hash_repaired);
+       dst->ln_local_lpf_scanned = cpu_to_le64(src->ln_local_lpf_scanned);
+       dst->ln_local_lpf_moved = cpu_to_le64(src->ln_local_lpf_moved);
+       dst->ln_local_lpf_skipped = cpu_to_le64(src->ln_local_lpf_skipped);
+       dst->ln_local_lpf_failed = cpu_to_le64(src->ln_local_lpf_failed);
        dst->ln_bitmap_size = cpu_to_le32(src->ln_bitmap_size);
 }
 
@@ -202,14 +251,13 @@ static void lfsck_namespace_record_failure(const struct lu_env *env,
 }
 
 /**
- * Load the MDT bitmap from the lfsck_namespace tracing file.
+ * Load the MDT bitmap from the lfsck_namespace trace file.
  *
  * \param[in] env      pointer to the thread context
  * \param[in] com      pointer to the lfsck component
  *
- * \retval             positive number for data corruption
  * \retval             0 for success
- * \retval             negative error number on failure
+ * \retval             negative error number on failure or data corruption
  */
 static int lfsck_namespace_load_bitmap(const struct lu_env *env,
                                       struct lfsck_component *com)
@@ -259,14 +307,8 @@ static int lfsck_namespace_load_bitmap(const struct lu_env *env,
        rc = dt_xattr_get(env, obj,
                          lfsck_buf_get(env, bitmap->data, size),
                          XATTR_NAME_LFSCK_BITMAP, BYPASS_CAPA);
-       if (rc == -ERANGE || rc == -ENODATA || rc == 0)
-               RETURN(1);
-
-       if (rc < 0)
-               RETURN(rc);
-
        if (rc != size)
-               RETURN(rc);
+               RETURN(rc >= 0 ? -EINVAL : rc);
 
        if (cfs_bitmap_check_empty(bitmap))
                lad->lad_incomplete = 0;
@@ -277,9 +319,19 @@ 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)
@@ -299,7 +351,7 @@ 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;
                }
@@ -308,13 +360,22 @@ 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, BYPASS_CAPA);
+               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;
@@ -325,6 +386,9 @@ static int lfsck_namespace_store(const struct lu_env *env,
        __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) {
@@ -356,6 +420,20 @@ static int lfsck_namespace_store(const struct lu_env *env,
                        GOTO(out, rc);
        }
 
+#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, lfsck->li_bottom, handle);
        if (rc != 0)
                GOTO(out, rc);
@@ -369,6 +447,13 @@ static int lfsck_namespace_store(const struct lu_env *env,
                                  XATTR_NAME_LFSCK_BITMAP, 0, handle,
                                  BYPASS_CAPA);
 
+#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, BYPASS_CAPA);
+#endif
+
        GOTO(out, rc);
 
 out:
@@ -391,18 +476,18 @@ 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);
        return rc;
 }
 
 /**
- * Update the namespace LFSCK tracing file for the given @fid
+ * Update the namespace LFSCK trace file for the given @fid
  *
  * \param[in] env      pointer to the thread context
  * \param[in] com      pointer to the lfsck component
  * \param[in] fid      the fid which flags to be updated in the lfsck
- *                     tracing file
+ *                     trace file
  * \param[in] add      true if add new flags, otherwise remove flags
  *
  * \retval             0 for succeed or nothing to be done
@@ -495,7 +580,7 @@ log:
                dt_trans_stop(env, dev, th);
 
        CDEBUG(D_LFSCK, "%s: namespace LFSCK %s flags for "DFID" in the "
-              "tracing file, flags %x, old %x, new %x: rc = %d\n",
+              "trace file, flags %x, old %x, new %x: rc = %d\n",
               lfsck_lfsck2name(lfsck), add ? "add" : "del", PFID(fid),
               (__u32)flags, (__u32)old, (__u32)new, rc);
 
@@ -505,9 +590,9 @@ unlock:
        return rc;
 }
 
-static int lfsck_namespace_check_exist(const struct lu_env *env,
-                                      struct dt_object *dir,
-                                      struct dt_object *obj, const char *name)
+int lfsck_namespace_check_exist(const struct lu_env *env,
+                               struct dt_object *dir,
+                               struct dt_object *obj, const char *name)
 {
        struct lu_fid    *fid = &lfsck_env_info(env)->lti_fid;
        int               rc;
@@ -727,6 +812,8 @@ static int lfsck_namespace_filter_linkea_entry(struct linkea_data *ldata,
  *  type "O":          The MDT-object has no linkEA, and there is no name
  *                     entry that references the MDT-object.
  *
+ *  type "S":          The orphan MDT-object is a shard of a striped directory
+ *
  * \see lfsck_layout_recreate_parent() for more types.
  *
  * The orphan name will be like:
@@ -749,6 +836,7 @@ static int lfsck_namespace_insert_orphan(const struct lu_env *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;
        const struct lu_fid             *cfid   = lfsck_dto2fid(orphan);
        const struct lu_fid             *pfid;
        struct lfsck_instance           *lfsck  = com->lc_lfsck;
@@ -852,6 +940,13 @@ static int lfsck_namespace_insert_orphan(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, orphan, la, th);
+       if (rc != 0)
+               GOTO(stop, rc);
+
        rc = dt_trans_start_local(env, dev, th);
        if (rc != 0)
                GOTO(stop, rc);
@@ -902,6 +997,11 @@ 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);
+
        GOTO(stop, rc = (rc == 0 ? 1 : rc));
 
 unlock:
@@ -1001,6 +1101,10 @@ static int lfsck_namespace_insert_normal(const struct lu_env *env,
        if (rc != 0)
                GOTO(stop, rc);
 
+       rc = dt_declare_attr_set(env, child, la, th);
+       if (rc != 0)
+               GOTO(stop, rc);
+
        rc = dt_trans_start_local(env, dev, th);
        if (rc != 0)
                GOTO(stop, rc);
@@ -1020,6 +1124,10 @@ static int lfsck_namespace_insert_normal(const struct lu_env *env,
 
        la->la_ctime = cfs_time_current_sec();
        rc = dt_attr_set(env, parent, la, th, BYPASS_CAPA);
+       if (rc != 0)
+               GOTO(stop, rc);
+
+       rc = dt_attr_set(env, child, la, th, BYPASS_CAPA);
 
        GOTO(stop, rc = (rc == 0 ? 1 : rc));
 
@@ -1061,11 +1169,13 @@ log:
  * \param[in] type     the orphan's type to be created
  *
  *  type "P":          The orphan object to be created was a parent directory
- *                     of some DMT-object which linkEA shows that the @orphan
+ *                     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
@@ -1073,7 +1183,8 @@ log:
 static int lfsck_namespace_create_orphan_remote(const struct lu_env *env,
                                                struct lfsck_component *com,
                                                struct dt_object *orphan,
-                                               __u32 type)
+                                               __u32 type,
+                                               struct lmv_mds_md_v1 *lmv)
 {
        struct lfsck_thread_info        *info   = lfsck_env_info(env);
        struct lfsck_request            *lr     = &info->lti_lr;
@@ -1122,6 +1233,13 @@ static int lfsck_namespace_create_orphan_remote(const struct lu_env *env,
        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);
@@ -1160,18 +1278,21 @@ out:
  * \param[in] type     the orphan's type to be created
  *
  *  type "P":          The orphan object to be created was a parent directory
- *                     of some DMT-object which linkEA shows that the @orphan
+ *                     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)
+                                              __u32 type,
+                                              struct lmv_mds_md_v1 *lmv)
 {
        struct lfsck_thread_info        *info   = lfsck_env_info(env);
        struct lu_attr                  *la     = &info->lti_la;
@@ -1180,6 +1301,7 @@ static int lfsck_namespace_create_orphan_local(const struct lu_env *env,
        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 lfsck_instance           *lfsck  = com->lc_lfsck;
@@ -1190,6 +1312,7 @@ static int lfsck_namespace_create_orphan_local(const struct lu_env *env,
        struct lustre_handle             lh     = { 0 };
        struct linkea_data               ldata  = { 0 };
        struct lu_buf                    linkea_buf;
+       struct lu_buf                    lmv_buf;
        char                             name[32];
        int                              namelen;
        int                              idx    = 0;
@@ -1266,6 +1389,17 @@ static int lfsck_namespace_create_orphan_local(const struct lu_env *env,
        if (rc != 0)
                GOTO(stop, rc);
 
+       if (lmv != NULL) {
+               lmv->lmv_magic = LMV_MAGIC;
+               lmv->lmv_master_mdt_index = lfsck_dev_idx(dev);
+               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,
+                                         XATTR_NAME_LMV, 0, th);
+               if (rc != 0)
+                       GOTO(stop, rc);
+       }
+
        lfsck_buf_init(&linkea_buf, ldata.ld_buf->lb_buf,
                       ldata.ld_leh->leh_len);
        rc = dt_declare_xattr_set(env, child, &linkea_buf,
@@ -1315,6 +1449,13 @@ static int lfsck_namespace_create_orphan_local(const struct lu_env *env,
                        GOTO(unlock2, rc);
        }
 
+       if (lmv != NULL) {
+               rc = dt_xattr_set(env, child, &lmv_buf, XATTR_NAME_LMV, 0,
+                                 th, BYPASS_CAPA);
+               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);
@@ -1367,28 +1508,31 @@ log:
  * \param[in] orphan   pointer to the orphan MDT-object
  *
  *  type "P":          The orphan object to be created was a parent directory
- *                     of some DMT-object which linkEA shows that the @orphan
+ *                     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 dt_object *orphan,
+                                        struct lmv_mds_md_v1 *lmv)
 {
        struct lfsck_namespace *ns = com->lc_file_ram;
        int                     rc;
 
        if (dt_object_remote(orphan))
                rc = lfsck_namespace_create_orphan_remote(env, com, orphan,
-                                                         S_IFDIR);
+                                                         S_IFDIR, lmv);
        else
                rc = lfsck_namespace_create_orphan_local(env, com, orphan,
-                                                        S_IFDIR);
+                                                        S_IFDIR, lmv);
 
        if (rc != 0)
                ns->ln_flags |= LF_INCONSISTENT;
@@ -1999,7 +2143,7 @@ stop:
        dt_trans_stop(env, dev, th);
 
        /* We are not sure whether the child will become orphan or not.
-        * Record it in the LFSCK tracing file for further checking in
+        * Record it in the LFSCK trace file for further checking in
         * the second-stage scanning. */
        if (!update && !dec && rc == 0)
                lfsck_namespace_trace_update(env, com, cfid,
@@ -2242,6 +2386,7 @@ lfsck_namespace_dsd_single(const struct lu_env *env,
        struct lfsck_namespace   *ns            = com->lc_file_ram;
        struct lfsck_instance    *lfsck         = com->lc_lfsck;
        struct dt_object         *parent        = NULL;
+       struct lmv_mds_md_v1     *lmv;
        int                       rc            = 0;
        ENTRY;
 
@@ -2286,8 +2431,33 @@ lfsck_namespace_dsd_single(const struct lu_env *env,
                lfsck_ibits_unlock(lh, LCK_EX);
 
 lost_parent:
+               lmv = &info->lti_lmv;
+               rc = lfsck_read_stripe_lmv(env, child, lmv);
+               if (rc != 0 && rc != -ENODATA)
+                       GOTO(out, rc);
+
+               if (rc == -ENODATA || lmv->lmv_magic != LMV_MAGIC_STRIPE) {
+                       lmv = NULL;
+               } else if (lfsck_shard_name_to_index(env,
+                                       cname->ln_name, cname->ln_namelen,
+                                       S_IFDIR, cfid) < 0) {
+                       /* It is an invalid name entry, we
+                        * cannot trust the parent also. */
+                       rc = lfsck_namespace_shrink_linkea(env, com, child,
+                                               ldata, cname, tfid, true);
+                       if (rc < 0)
+                               GOTO(out, rc);
+
+                       snprintf(info->lti_tmpbuf, sizeof(info->lti_tmpbuf),
+                                "-"DFID, PFID(pfid));
+                       rc = lfsck_namespace_insert_orphan(env, com, child,
+                                               info->lti_tmpbuf, "S", NULL);
+
+                       GOTO(out, rc);
+               }
+
                /* Create the lost parent as an orphan. */
-               rc = lfsck_namespace_create_orphan(env, com, parent);
+               rc = lfsck_namespace_create_orphan(env, com, parent, lmv);
                if (rc >= 0) {
                        /* Add the missing name entry to the parent. */
                        rc = lfsck_namespace_insert_normal(env, com, parent,
@@ -2349,6 +2519,28 @@ lost_parent:
                }
 
                lfsck_ibits_unlock(lh, LCK_EX);
+               rc = lfsck_namespace_check_name(env, parent, child, cname);
+               if (rc == -ENOENT)
+                       goto lost_parent;
+
+               if (rc < 0)
+                       GOTO(out, rc);
+
+               /* It is an invalid name entry, drop it. */
+               if (unlikely(rc > 0)) {
+                       rc = lfsck_namespace_shrink_linkea(env, com, child,
+                                               ldata, cname, tfid, true);
+                       if (rc >= 0) {
+                               snprintf(info->lti_tmpbuf,
+                                        sizeof(info->lti_tmpbuf),
+                                        "-"DFID, PFID(pfid));
+                               rc = lfsck_namespace_insert_orphan(env, com,
+                                       child, info->lti_tmpbuf, "D", NULL);
+                       }
+
+                       GOTO(out, rc);
+               }
+
                /* Add the missing name entry back to the namespace. */
                rc = lfsck_namespace_insert_normal(env, com, parent, child,
                                                   cname->ln_name);
@@ -2405,6 +2597,9 @@ 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) {
@@ -2470,7 +2665,8 @@ lfsck_namespace_dsd_multiple(const struct lu_env *env,
        struct lfsck_bookmark    *bk            = &lfsck->li_bookmark_ram;
        struct dt_object         *parent        = NULL;
        struct linkea_data        ldata_new     = { 0 };
-       int                       count         = 0;
+       int                       dirent_count  = 0;
+       int                       linkea_count  = 0;
        int                       rc            = 0;
        bool                      once          = true;
        ENTRY;
@@ -2484,6 +2680,7 @@ again:
                /* Drop invalid linkEA entry. */
                if (!fid_is_sane(tfid)) {
                        linkea_del_buf(ldata, cname);
+                       linkea_count++;
                        continue;
                }
 
@@ -2517,6 +2714,7 @@ again:
                                 * child to be visible via other parent, then
                                 * remove this linkEA entry. */
                                linkea_del_buf(ldata, cname);
+                               linkea_count++;
                                continue;
                        }
 
@@ -2527,6 +2725,7 @@ again:
                if (unlikely(!dt_try_as_dir(env, parent))) {
                        lfsck_object_put(env, parent);
                        linkea_del_buf(ldata, cname);
+                       linkea_count++;
                        continue;
                }
 
@@ -2574,6 +2773,7 @@ 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. */
@@ -2610,13 +2810,13 @@ 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);
                }
@@ -2637,10 +2837,15 @@ 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);
        }
 
@@ -2653,7 +2858,6 @@ 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. */
@@ -2674,6 +2878,130 @@ next:
 }
 
 /**
+ * Repair the object's nlink attribute.
+ *
+ * If all the known name entries have been verified, then the object's hard
+ * link attribute should match the object's linkEA entries count unless the
+ * object's has too much hard link to be recorded in the linkEA. Such cases
+ * should have been marked in the LFSCK trace file. Otherwise, trust the
+ * linkEA to update the object's nlink attribute.
+ *
+ * \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
+ *                     and after the repairing
+ *
+ * \retval             positive number for repaired cases
+ * \retval             0 if nothing to be repaired
+ * \retval             negative error number on failure
+ */
+static int lfsck_namespace_repair_nlink(const struct lu_env *env,
+                                       struct lfsck_component *com,
+                                       struct dt_object *obj, __u32 *nlink)
+{
+       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;
+       const struct lu_fid             *cfid   = lfsck_dto2fid(obj);
+       struct dt_object                *child  = NULL;
+       struct thandle                  *th     = NULL;
+       struct linkea_data               ldata  = { 0 };
+       struct lustre_handle             lh     = { 0 };
+       __u32                            old    = *nlink;
+       int                              rc     = 0;
+       __u8                             flags;
+       ENTRY;
+
+       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);
+       if (rc != 0)
+               GOTO(log, rc);
+
+       th = dt_trans_create(env, dev);
+       if (IS_ERR(th))
+               GOTO(log, rc = PTR_ERR(th));
+
+       la->la_valid = LA_NLINK;
+       rc = dt_declare_attr_set(env, child, la, th);
+       if (rc != 0)
+               GOTO(stop, rc);
+
+       rc = dt_trans_start_local(env, dev, th);
+       if (rc != 0)
+               GOTO(stop, rc);
+
+       dt_write_lock(env, child, 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)
+               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);
+       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);
+
+       if (rc != 0)
+               GOTO(unlock, rc);
+
+       if (*nlink == ldata.ld_leh->leh_reccount)
+               GOTO(unlock, rc = 0);
+
+       la->la_nlink = *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);
+
+       GOTO(unlock, rc = (rc == 0 ? 1 : rc));
+
+unlock:
+       dt_write_unlock(env, child);
+
+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);
+
+       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);
+
+       if (rc != 0)
+               ns->ln_flags |= LF_INCONSISTENT;
+
+       return rc;
+}
+
+/**
  * Double scan the directory object for namespace LFSCK.
  *
  * This function will verify the <parent, child> pairs in the namespace tree:
@@ -2730,6 +3058,22 @@ static int lfsck_namespace_double_scan_dir(const struct lu_env *env,
 
        LASSERT(!dt_object_remote(child));
 
+       if (flags & LNTF_UNCERTAIN_LMV) {
+               if (flags & LNTF_RECHECK_NAME_HASH) {
+                       rc = lfsck_namespace_scan_shard(env, com, child);
+                       if (rc < 0)
+                               RETURN(rc);
+
+                       ns->ln_striped_shards_scanned++;
+               } else {
+                       ns->ln_striped_shards_skipped++;
+               }
+       }
+
+       flags &= ~(LNTF_RECHECK_NAME_HASH | LNTF_UNCERTAIN_LMV);
+       if (flags == 0)
+               RETURN(0);
+
        if (flags & (LNTF_CHECK_LINKEA | LNTF_CHECK_PARENT) &&
            !(lfsck->li_bookmark_ram.lb_param & LPF_ALL_TGT)) {
                CDEBUG(D_LFSCK, "%s: some MDT(s) maybe NOT take part in the"
@@ -2782,6 +3126,8 @@ 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);
@@ -3026,7 +3372,7 @@ lost_parent:
 
                                /* Create the lost parent as an orphan. */
                                rc = lfsck_namespace_create_orphan(env, com,
-                                                                  parent);
+                                                               parent, NULL);
                                if (rc < 0) {
                                        lfsck_object_put(env, parent);
 
@@ -3157,6 +3503,30 @@ lost_parent:
                        GOTO(out, rc = 0);
                }
 
+               rc = lfsck_namespace_check_name(env, parent, child, cname);
+               if (rc == -ENOENT)
+                       goto lost_parent;
+
+               if (rc < 0) {
+                       lfsck_object_put(env, parent);
+
+                       GOTO(out, rc);
+               }
+
+               /* It is an invalid name entry, drop it. */
+               if (unlikely(rc > 0)) {
+                       lfsck_object_put(env, parent);
+                       rc = lfsck_namespace_shrink_linkea(env, com, child,
+                                               &ldata, cname, pfid, true);
+                       if (rc < 0)
+                               GOTO(out, rc);
+
+                       if (rc > 0)
+                               repaired = true;
+
+                       continue;
+               }
+
                /* Add the missing name entry back to the namespace. */
                rc = lfsck_namespace_insert_normal(env, com, parent, child,
                                                   cname->ln_name);
@@ -3227,8 +3597,12 @@ out:
                return rc;
 
        if (la->la_nlink != count) {
-               /* XXX: there will be other patch(es) for MDT-object
-                *      hard links verification. */
+               rc = lfsck_namespace_repair_nlink(env, com, child,
+                                                 &la->la_nlink);
+               if (rc > 0) {
+                       ns->ln_objs_nlink_repaired++;
+                       rc = 0;
+               }
        }
 
        if (repaired) {
@@ -3267,6 +3641,20 @@ static void lfsck_namespace_dump_statistics(struct seq_file *m,
                      "multiple_referenced_repaired: "LPU64"\n"
                      "bad_file_type_repaired: "LPU64"\n"
                      "lost_dirent_repaired: "LPU64"\n"
+                     "local_lost_found_scanned: "LPU64"\n"
+                     "local_lost_found_moved: "LPU64"\n"
+                     "local_lost_found_skipped: "LPU64"\n"
+                     "local_lost_found_failed: "LPU64"\n"
+                     "striped_dirs_scanned: "LPU64"\n"
+                     "striped_dirs_repaired: "LPU64"\n"
+                     "striped_dirs_failed: "LPU64"\n"
+                     "striped_dirs_disabled: "LPU64"\n"
+                     "striped_dirs_skipped: "LPU64"\n"
+                     "striped_shards_scanned: "LPU64"\n"
+                     "striped_shards_repaired: "LPU64"\n"
+                     "striped_shards_failed: "LPU64"\n"
+                     "striped_shards_skipped: "LPU64"\n"
+                     "name_hash_repaired: "LPU64"\n"
                      "success_count: %u\n"
                      "run_time_phase1: %u seconds\n"
                      "run_time_phase2: %u seconds\n",
@@ -3288,11 +3676,48 @@ static void lfsck_namespace_dump_statistics(struct seq_file *m,
                      ns->ln_mul_ref_repaired,
                      ns->ln_bad_type_repaired,
                      ns->ln_lost_dirent_repaired,
+                     ns->ln_local_lpf_scanned,
+                     ns->ln_local_lpf_moved,
+                     ns->ln_local_lpf_skipped,
+                     ns->ln_local_lpf_failed,
+                     ns->ln_striped_dirs_scanned,
+                     ns->ln_striped_dirs_repaired,
+                     ns->ln_striped_dirs_failed,
+                     ns->ln_striped_dirs_disabled,
+                     ns->ln_striped_dirs_skipped,
+                     ns->ln_striped_shards_scanned,
+                     ns->ln_striped_shards_repaired,
+                     ns->ln_striped_shards_failed,
+                     ns->ln_striped_shards_skipped,
+                     ns->ln_name_hash_repaired,
                      ns->ln_success_count,
                      time_phase1,
                      time_phase2);
 }
 
+static void lfsck_namespace_release_lmv(const struct lu_env *env,
+                                       struct lfsck_component *com)
+{
+       struct lfsck_instance           *lfsck  = com->lc_lfsck;
+       struct lfsck_namespace          *ns     = com->lc_file_ram;
+
+       while (!list_empty(&lfsck->li_list_lmv)) {
+               struct lfsck_lmv_unit   *llu;
+               struct lfsck_lmv        *llmv;
+
+               llu = list_entry(lfsck->li_list_lmv.next,
+                                struct lfsck_lmv_unit, llu_link);
+               llmv = &llu->llu_lmv;
+
+               LASSERTF(atomic_read(&llmv->ll_ref) == 1,
+                        "still in using: %u\n",
+                        atomic_read(&llmv->ll_ref));
+
+               ns->ln_striped_dirs_skipped++;
+               lfsck_lmv_put(env, llmv);
+       }
+}
+
 /* namespace APIs */
 
 static int lfsck_namespace_reset(const struct lu_env *env,
@@ -3349,7 +3774,7 @@ static int lfsck_namespace_reset(const struct lu_env *env,
        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);
 
@@ -3377,24 +3802,108 @@ lfsck_namespace_fail(const struct lu_env *env, struct lfsck_component *com,
        up_write(&com->lc_sem);
 }
 
-static int lfsck_namespace_checkpoint(const struct lu_env *env,
-                                     struct lfsck_component *com, bool init)
+static void lfsck_namespace_close_dir(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;
+       struct lfsck_namespace          *ns     = com->lc_file_ram;
+       struct lfsck_assistant_data     *lad    = com->lc_data;
+       struct lfsck_instance           *lfsck  = com->lc_lfsck;
+       struct lfsck_lmv                *llmv   = lfsck->li_lmv;
+       struct lfsck_namespace_req      *lnr;
+       __u32                            size   =
+                               sizeof(*lnr) + LFSCK_TMPBUF_LEN;
+       bool                             wakeup = false;
+       ENTRY;
 
-       if (!init) {
-               rc = lfsck_checkpoint_generic(env, com);
-               if (rc != 0)
-                       goto log;
+       if (llmv == NULL)
+               RETURN_EXIT;
+
+       OBD_ALLOC(lnr, size);
+       if (lnr == NULL) {
+               ns->ln_striped_dirs_skipped++;
+
+               RETURN_EXIT;
        }
 
-       down_write(&com->lc_sem);
-       if (init) {
-               ns->ln_pos_latest_start = lfsck->li_pos_checkpoint;
-       } else {
-               ns->ln_pos_last_checkpoint = lfsck->li_pos_checkpoint;
+       /* 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_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;
+
+       spin_lock(&lad->lad_lock);
+       if (lad->lad_assistant_status < 0) {
+               spin_unlock(&lad->lad_lock);
+               lfsck_namespace_assistant_req_fini(env, &lnr->lnr_lar);
+               ns->ln_striped_dirs_skipped++;
+
+               RETURN_EXIT;
+       }
+
+       list_add_tail(&lnr->lnr_lar.lar_list, &lad->lad_req_list);
+       if (lad->lad_prefetched == 0)
+               wakeup = true;
+
+       lad->lad_prefetched++;
+       spin_unlock(&lad->lad_lock);
+       if (wakeup)
+               wake_up_all(&lad->lad_thread.t_ctl_waitq);
+
+       EXIT;
+}
+
+static int lfsck_namespace_open_dir(const struct lu_env *env,
+                                   struct lfsck_component *com)
+{
+       struct lfsck_instance   *lfsck  = com->lc_lfsck;
+       struct lfsck_namespace  *ns     = com->lc_file_ram;
+       struct lfsck_lmv        *llmv   = lfsck->li_lmv;
+       int                      rc     = 0;
+       ENTRY;
+
+       if (llmv == NULL)
+               RETURN(0);
+
+       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)) {
+                       lmv->lmv_master_mdt_index =
+                               lfsck_dev_idx(lfsck->li_bottom);
+                       ns->ln_flags |= LF_INCONSISTENT;
+                       llmv->ll_lmv_updated = 1;
+               }
+       } else {
+               rc = lfsck_namespace_verify_stripe_slave(env, com,
+                                       lfsck->li_obj_dir, llmv);
+       }
+
+       RETURN(rc > 0 ? 0 : rc);
+}
+
+static int lfsck_namespace_checkpoint(const struct lu_env *env,
+                                     struct lfsck_component *com, bool init)
+{
+       struct lfsck_instance   *lfsck = com->lc_lfsck;
+       struct lfsck_namespace  *ns    = com->lc_file_ram;
+       int                      rc;
+
+       if (!init) {
+               rc = lfsck_checkpoint_generic(env, com);
+               if (rc != 0)
+                       goto log;
+       }
+
+       down_write(&com->lc_sem);
+       if (init) {
+               ns->ln_pos_latest_start = lfsck->li_pos_checkpoint;
+       } else {
+               ns->ln_pos_last_checkpoint = lfsck->li_pos_checkpoint;
                ns->ln_run_time_phase1 += cfs_duration_sec(cfs_time_current() +
                                HALF_SEC - lfsck->li_time_last_checkpoint);
                ns->ln_time_last_checkpoint = cfs_time_current_sec();
@@ -3402,7 +3911,7 @@ 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:
@@ -3425,17 +3934,17 @@ static int lfsck_namespace_prep(const struct lu_env *env,
        int                      rc;
 
        rc = lfsck_namespace_load_bitmap(env, com);
-       if (rc > 0 || (rc == 0 && ns->ln_status == LS_COMPLETED)) {
+       if (rc != 0 || ns->ln_status == LS_COMPLETED) {
                rc = lfsck_namespace_reset(env, com, false);
                if (rc == 0)
                        rc = lfsck_set_param(env, lfsck, lsp->lsp_start, true);
-       }
 
-       if (rc != 0) {
-               CDEBUG(D_LFSCK, "%s: namespace LFSCK prep failed: rc = %d\n",
-                      lfsck_lfsck2name(lfsck), rc);
+               if (rc != 0) {
+                       CDEBUG(D_LFSCK, "%s: namespace LFSCK prep failed: "
+                              "rc = %d\n", lfsck_lfsck2name(lfsck), rc);
 
-               return rc;
+                       return rc;
+               }
        }
 
        down_write(&com->lc_sem);
@@ -3473,6 +3982,16 @@ static int lfsck_namespace_prep(const struct lu_env *env,
                        ns->ln_mul_ref_repaired = 0;
                        ns->ln_bad_type_repaired = 0;
                        ns->ln_lost_dirent_repaired = 0;
+                       ns->ln_striped_dirs_scanned = 0;
+                       ns->ln_striped_dirs_repaired = 0;
+                       ns->ln_striped_dirs_failed = 0;
+                       ns->ln_striped_dirs_disabled = 0;
+                       ns->ln_striped_dirs_skipped = 0;
+                       ns->ln_striped_shards_scanned = 0;
+                       ns->ln_striped_shards_repaired = 0;
+                       ns->ln_striped_shards_failed = 0;
+                       ns->ln_striped_shards_skipped = 0;
+                       ns->ln_name_hash_repaired = 0;
                        fid_zero(&ns->ln_fid_latest_scanned_phase2);
                        if (list_empty(&com->lc_link_dir))
                                list_add_tail(&com->lc_link_dir,
@@ -3552,7 +4071,7 @@ static int lfsck_namespace_exec_oit(const struct lu_env *env,
 
        /* 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 tracing file to be too large. */
+        * 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);
@@ -3561,7 +4080,10 @@ static int lfsck_namespace_exec_oit(const struct lu_env *env,
                if (rc != 0)
                        GOTO(out, rc);
 
-               if (la->la_nlink > 1)
+               /* "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);
 
@@ -3600,7 +4122,10 @@ static int lfsck_namespace_exec_oit(const struct lu_env *env,
                        if (rc != 0)
                                GOTO(out, rc);
 
-                       if (la->la_nlink > 1)
+                       /* "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);
                }
@@ -3671,6 +4196,8 @@ static int lfsck_namespace_post(const struct lu_env *env,
        lfsck_post_generic(env, com, &result);
 
        down_write(&com->lc_sem);
+       lfsck_namespace_release_lmv(env, com);
+
        spin_lock(&lfsck->li_lock);
        if (!init)
                ns->ln_pos_last_checkpoint = lfsck->li_pos_checkpoint;
@@ -3681,8 +4208,9 @@ static int lfsck_namespace_post(const struct lu_env *env,
                list_del_init(&com->lc_link_dir);
                list_move_tail(&com->lc_link, &lfsck->li_list_double_scan);
        } else if (result == 0) {
-               ns->ln_status = lfsck->li_status;
-               if (ns->ln_status == 0)
+               if (lfsck->li_status != 0)
+                       ns->ln_status = lfsck->li_status;
+               else
                        ns->ln_status = LS_STOPPED;
                if (ns->ln_status != LS_PAUSED) {
                        list_del_init(&com->lc_link_dir);
@@ -3703,7 +4231,7 @@ 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",
@@ -3775,7 +4303,8 @@ 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 = com->lc_new_checked * HZ;
+               __u64 new_checked = msecs_to_jiffies(com->lc_new_checked *
+                                                    MSEC_PER_SEC);
                __u32 rtime = ns->ln_run_time_phase1 +
                              cfs_duration_sec(duration + HALF_SEC);
 
@@ -3829,7 +4358,8 @@ lfsck_namespace_dump(const struct lu_env *env, struct lfsck_component *com,
                                com->lc_new_checked;
                __u64 speed1 = ns->ln_items_checked;
                __u64 speed2 = checked;
-               __u64 new_checked = com->lc_new_checked * HZ;
+               __u64 new_checked = msecs_to_jiffies(com->lc_new_checked *
+                                                    MSEC_PER_SEC);
                __u32 rtime = ns->ln_run_time_phase2 +
                              cfs_duration_sec(duration + HALF_SEC);
 
@@ -3881,9 +4411,27 @@ out:
 static int lfsck_namespace_double_scan(const struct lu_env *env,
                                       struct lfsck_component *com)
 {
-       struct lfsck_namespace *ns = com->lc_file_ram;
+       struct lfsck_namespace          *ns     = com->lc_file_ram;
+       struct lfsck_assistant_data     *lad    = com->lc_data;
+       struct lfsck_tgt_descs          *ltds   = &com->lc_lfsck->li_mdt_descs;
+       struct lfsck_tgt_desc           *ltd;
+       struct lfsck_tgt_desc           *next;
+       int                              rc;
+
+       rc = lfsck_double_scan_generic(env, com, ns->ln_status);
+       if (thread_is_stopped(&lad->lad_thread)) {
+               LASSERT(list_empty(&lad->lad_req_list));
+               LASSERT(list_empty(&lad->lad_mdt_phase1_list));
+
+               spin_lock(&ltds->ltd_lock);
+               list_for_each_entry_safe(ltd, next, &lad->lad_mdt_phase2_list,
+                                        ltd_namespace_phase_list) {
+                       list_del_init(&ltd->ltd_namespace_phase_list);
+               }
+               spin_unlock(&ltds->ltd_lock);
+       }
 
-       return lfsck_double_scan_generic(env, com, ns->ln_status);
+       return rc;
 }
 
 static void lfsck_namespace_data_release(const struct lu_env *env,
@@ -3900,6 +4448,7 @@ static void lfsck_namespace_data_release(const struct lu_env *env,
        LASSERT(list_empty(&lad->lad_req_list));
 
        com->lc_data = NULL;
+       lfsck_namespace_release_lmv(env, com);
 
        spin_lock(&ltds->ltd_lock);
        list_for_each_entry_safe(ltd, next, &lad->lad_mdt_phase1_list,
@@ -3916,14 +4465,46 @@ static void lfsck_namespace_data_release(const struct lu_env *env,
        }
        spin_unlock(&ltds->ltd_lock);
 
-       CFS_FREE_BITMAP(lad->lad_bitmap);
+       if (likely(lad->lad_bitmap != NULL))
+               CFS_FREE_BITMAP(lad->lad_bitmap);
 
        OBD_FREE_PTR(lad);
 }
 
+static void lfsck_namespace_quit(const struct lu_env *env,
+                                struct lfsck_component *com)
+{
+       struct lfsck_assistant_data     *lad    = com->lc_data;
+       struct lfsck_tgt_descs          *ltds   = &com->lc_lfsck->li_mdt_descs;
+       struct lfsck_tgt_desc           *ltd;
+       struct lfsck_tgt_desc           *next;
+
+       LASSERT(lad != NULL);
+
+       lfsck_quit_generic(env, com);
+
+       LASSERT(thread_is_init(&lad->lad_thread) ||
+               thread_is_stopped(&lad->lad_thread));
+       LASSERT(list_empty(&lad->lad_req_list));
+
+       lfsck_namespace_release_lmv(env, com);
+
+       spin_lock(&ltds->ltd_lock);
+       list_for_each_entry_safe(ltd, next, &lad->lad_mdt_phase1_list,
+                                ltd_namespace_phase_list) {
+               list_del_init(&ltd->ltd_namespace_phase_list);
+       }
+       list_for_each_entry_safe(ltd, next, &lad->lad_mdt_phase2_list,
+                                ltd_namespace_phase_list) {
+               list_del_init(&ltd->ltd_namespace_phase_list);
+       }
+       spin_unlock(&ltds->ltd_lock);
+}
+
 static int lfsck_namespace_in_notify(const struct lu_env *env,
                                     struct lfsck_component *com,
-                                    struct lfsck_request *lr)
+                                    struct lfsck_request *lr,
+                                    struct thandle *th)
 {
        struct lfsck_instance           *lfsck = com->lc_lfsck;
        struct lfsck_namespace          *ns    = com->lc_file_ram;
@@ -3937,6 +4518,7 @@ static int lfsck_namespace_in_notify(const struct lu_env *env,
        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",
@@ -3950,8 +4532,20 @@ static int lfsck_namespace_in_notify(const struct lu_env *env,
                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);
+                                                        lr->lr_type, lmv);
 
                GOTO(out_create, rc = (rc == 1) ? 0 : rc);
 
@@ -3966,6 +4560,92 @@ out_create:
 
                return rc;
        }
+       case LE_SKIP_NLINK_DECLARE: {
+               struct dt_object        *obj   = com->lc_obj;
+               struct lu_fid           *key   = &lfsck_env_info(env)->lti_fid3;
+               __u8                     flags = 0;
+
+               LASSERT(th != NULL);
+
+               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);
+
+               RETURN(rc);
+       }
+       case LE_SKIP_NLINK: {
+               struct dt_object        *obj   = com->lc_obj;
+               struct lu_fid           *key   = &lfsck_env_info(env)->lti_fid3;
+               __u8                     flags = 0;
+               bool                     exist = false;
+               ENTRY;
+
+               LASSERT(th != NULL);
+
+               fid_cpu_to_be(key, &lr->lr_fid);
+               rc = dt_lookup(env, obj, (struct dt_rec *)&flags,
+                              (const struct dt_key *)key, BYPASS_CAPA);
+               if (rc == 0) {
+                       if (flags & LNTF_SKIP_NLINK)
+                               RETURN(0);
+
+                       exist = true;
+               } else if (rc != -ENOENT) {
+                       GOTO(log, rc);
+               }
+
+               flags |= LNTF_SKIP_NLINK;
+               if (exist) {
+                       rc = dt_delete(env, obj, (const struct dt_key *)key,
+                                      th, BYPASS_CAPA);
+                       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);
+
+               GOTO(log, rc);
+
+log:
+               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);
+
+               if (rc != 0)
+                       /* If we cannot record this object in the LFSCK tracing,
+                        * we have to mark the LFSC as LF_INCOMPLETE, then the
+                        * LFSCK will skip nlink attribute verification for
+                        * all objects. */
+                       ns->ln_flags |= LF_INCOMPLETE;
+
+               return 0;
+       }
+       case LE_SET_LMV_MASTER: {
+               struct dt_object        *obj;
+
+               obj = lfsck_object_find_by_dev(env, lfsck->li_bottom,
+                                              &lr->lr_fid);
+               if (IS_ERR(obj))
+                       RETURN(PTR_ERR(obj));
+
+               rc = lfsck_namespace_notify_lmv_master_local(env, com, obj);
+               lfsck_object_put(env, obj);
+
+               RETURN(rc > 0 ? 0 : rc);
+       }
+       case LE_SET_LMV_SLAVE: {
+               if (!(lr->lr_flags & LEF_RECHECK_NAME_HASH))
+                       ns->ln_striped_shards_repaired++;
+
+               rc = lfsck_namespace_trace_update(env, com, &lr->lr_fid,
+                                                 LNTF_RECHECK_NAME_HASH, true);
+
+               RETURN(rc > 0 ? 0 : rc);
+       }
        case LE_PHASE1_DONE:
        case LE_PHASE2_DONE:
        case LE_PEER_EXIT:
@@ -4055,6 +4735,8 @@ static int lfsck_namespace_query(const struct lu_env *env,
 static struct lfsck_operations lfsck_namespace_ops = {
        .lfsck_reset            = lfsck_namespace_reset,
        .lfsck_fail             = lfsck_namespace_fail,
+       .lfsck_close_dir        = lfsck_namespace_close_dir,
+       .lfsck_open_dir         = lfsck_namespace_open_dir,
        .lfsck_checkpoint       = lfsck_namespace_checkpoint,
        .lfsck_prep             = lfsck_namespace_prep,
        .lfsck_exec_oit         = lfsck_namespace_exec_oit,
@@ -4063,7 +4745,7 @@ static struct lfsck_operations lfsck_namespace_ops = {
        .lfsck_dump             = lfsck_namespace_dump,
        .lfsck_double_scan      = lfsck_namespace_double_scan,
        .lfsck_data_release     = lfsck_namespace_data_release,
-       .lfsck_quit             = lfsck_quit_generic,
+       .lfsck_quit             = lfsck_namespace_quit,
        .lfsck_in_notify        = lfsck_namespace_in_notify,
        .lfsck_query            = lfsck_namespace_query,
 };
@@ -4102,11 +4784,13 @@ int lfsck_namespace_repair_dangling(const struct lu_env *env,
        struct dt_allocation_hint       *hint   = &info->lti_hint;
        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;
        const struct lu_name            *cname;
        struct linkea_data               ldata  = { 0 };
        struct lustre_handle             lh     = { 0 };
        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);
@@ -4194,9 +4878,31 @@ int lfsck_namespace_repair_dangling(const struct lu_env *env,
                rc = dt_declare_ref_add(env, child, th);
                if (rc != 0)
                        GOTO(stop, rc);
+
+               /* 5a. generate slave LMV EA. */
+               if (lnr->lnr_lmv != NULL && lnr->lnr_lmv->ll_lmv_master) {
+                       int idx;
+
+                       idx = lfsck_shard_name_to_index(env,
+                                       lnr->lnr_name, lnr->lnr_namelen,
+                                       type, lfsck_dto2fid(child));
+                       if (unlikely(idx < 0))
+                               GOTO(stop, rc = idx);
+
+                       *lmv2 = lnr->lnr_lmv->ll_lmv;
+                       lmv2->lmv_magic = LMV_MAGIC_STRIPE;
+                       lmv2->lmv_master_mdt_index = idx;
+
+                       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,
+                                                 XATTR_NAME_LMV, 0, th);
+                       if (rc != 0)
+                               GOTO(stop, rc);
+               }
        }
 
-       /* 5a. insert linkEA for child */
+       /* 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,
@@ -4238,9 +4944,17 @@ int lfsck_namespace_repair_dangling(const struct lu_env *env,
                rc = dt_ref_add(env, child, 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);
+                       if (rc != 0)
+                               GOTO(unlock, rc);
+               }
        }
 
-       /* 5b. insert linkEA for child. */
+       /* 6b. insert linkEA for child. */
        rc = dt_xattr_set(env, child, &linkea_buf,
                          XATTR_NAME_LINK, 0, th, BYPASS_CAPA);
 
@@ -4295,6 +5009,7 @@ static int lfsck_namespace_assistant_handler_p1(const struct lu_env *env,
        bool                        remove;
        bool                        newdata;
        bool                        log      = false;
+       bool                        bad_hash = false;
        int                         idx      = 0;
        int                         count    = 0;
        int                         rc;
@@ -4321,10 +5036,22 @@ static int lfsck_namespace_assistant_handler_p1(const struct lu_env *env,
                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))))
                GOTO(out, rc = 0);
 
+       if (lnr->lnr_lmv != NULL && lnr->lnr_lmv->ll_lmv_master) {
+               rc = lfsck_namespace_handle_striped_master(env, com, lnr);
+
+               RETURN(rc);
+       }
+
        idx = lfsck_find_mdt_idx_by_fid(env, lfsck, &lnr->lnr_fid);
        if (idx < 0)
                GOTO(out, rc = idx);
@@ -4370,6 +5097,13 @@ static int lfsck_namespace_assistant_handler_p1(const struct lu_env *env,
 dangling:
                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,
+                                       lnr->lnr_name, lnr->lnr_namelen)) {
+                               type = LNIT_BAD_DIRENT;
+
+                               GOTO(out, rc);
+                       }
+
                        type = LNIT_DANGLING;
                        rc = lfsck_namespace_repair_dangling(env, com,
                                                             obj, lnr);
@@ -4440,6 +5174,16 @@ again:
 
                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)) {
+                       type = LNIT_BAD_DIRENT;
+
+                       GOTO(stop, rc = 0);
+               }
+
                /* If the file type stored in the name entry does not match
                 * the file type claimed by the object, and the object does
                 * not recognize the name entry, then it is quite possible
@@ -4514,6 +5258,33 @@ nodata:
                        GOTO(stop, rc);
 
                rc = lfsck_links_write(env, obj, &ldata, handle);
+               if (unlikely(rc == -ENOSPC) &&
+                   S_ISREG(lfsck_object_type(obj)) && !dt_object_remote(obj)) {
+                       if (handle != NULL) {
+                               LASSERT(dt_write_locked(env, obj));
+
+                               dt_write_unlock(env, obj);
+                               dtlocked = false;
+
+                               dt_trans_stop(env, dev, handle);
+                               handle = NULL;
+
+                               lfsck_ibits_unlock(&lh, LCK_EX);
+                       }
+
+                       rc = lfsck_namespace_trace_update(env, com,
+                                       &lnr->lnr_fid, LNTF_SKIP_NLINK, true);
+                       if (rc != 0)
+                               /* If we cannot record this object in the
+                                * LFSCK tracing, we have to mark the LFSCK
+                                * as LF_INCOMPLETE, then the LFSCK will
+                                * skip nlink attribute verification for
+                                * all objects. */
+                               ns->ln_flags |= LF_INCOMPLETE;
+
+                       GOTO(out, rc = 0);
+               }
+
                if (rc != 0)
                        GOTO(stop, rc);
 
@@ -4567,6 +5338,19 @@ stop:
 out:
        lfsck_ibits_unlock(&lh, LCK_EX);
 
+       if (!name_is_dot_or_dotdot(lnr->lnr_name, lnr->lnr_namelen) &&
+           !lfsck_is_valid_slave_name_entry(env, lnr->lnr_lmv,
+                                            lnr->lnr_name, lnr->lnr_namelen) &&
+           type != LNIT_BAD_DIRENT) {
+               ns->ln_flags |= LF_INCONSISTENT;
+
+               log = false;
+               rc = lfsck_namespace_repair_bad_name_hash(env, com, dir,
+                                               lnr->lnr_lmv, lnr->lnr_name);
+               if (rc >= 0)
+                       bad_hash = true;
+       }
+
        if (rc >= 0) {
                switch (type) {
                case LNIT_BAD_TYPE:
@@ -4644,6 +5428,21 @@ out:
                                               false);
                }
 
+               if (bad_hash) {
+                       ns->ln_name_hash_repaired++;
+
+                       /* Not count repeatedly. */
+                       if (!repaired)
+                               ns->ln_items_repaired++;
+
+                       if (bk->lb_param & LPF_DRYRUN &&
+                           lfsck_pos_is_zero(&ns->ln_pos_first_inconsistent))
+                               lfsck_pos_fill(env, lfsck,
+                                              &ns->ln_pos_first_inconsistent,
+                                              false);
+               }
+
+
                rc = 0;
        }
        up_write(&com->lc_sem);
@@ -4654,6 +5453,442 @@ out:
        return rc;
 }
 
+/**
+ * Handle one orphan under the backend /lost+found directory
+ *
+ * Insert the orphan FID into the namespace LFSCK trace file for further
+ * processing (via the subsequent namespace LFSCK second-stage scanning).
+ * At the same time, remove the orphan name entry from backend /lost+found
+ * directory. There is an interval between the orphan name entry removed
+ * from the backend /lost+found directory and the orphan FID in the LFSCK
+ * trace file handled. In such interval, the LFSCK can be reset, then
+ * all the FIDs recorded in the namespace LFSCK trace file will be dropped.
+ * To guarantee that the orphans can be found when LFSCK run next time
+ * without e2fsck again, when remove the orphan name entry, the LFSCK
+ * will set the orphan's ctime attribute as 1. Since normal applications
+ * cannot change the object's ctime attribute as 1. Then when LFSCK run
+ * next time, it can record the object (that ctime is 1) in the namespace
+ * LFSCK trace file during the first-stage scanning.
+ *
+ * \param[in] env      pointer to the thread context
+ * \param[in] com      pointer to the lfsck component
+ * \param[in] parent   pointer to the object for the backend /lost+found
+ * \param[in] ent      pointer to the name entry for the target under the
+ *                     backend /lost+found
+ *
+ * \retval             positive for repaired
+ * \retval             0 if needs to repair nothing
+ * \retval             negative error number on failure
+ */
+static int lfsck_namespace_scan_local_lpf_one(const struct lu_env *env,
+                                             struct lfsck_component *com,
+                                             struct dt_object *parent,
+                                             struct lu_dirent *ent)
+{
+       struct lfsck_thread_info        *info   = lfsck_env_info(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_device                *dev    = lfsck->li_bottom;
+       struct dt_object                *child  = NULL;
+       struct thandle                  *th     = NULL;
+       int                              rc     = 0;
+       __u8                             flags  = 0;
+       bool                             exist  = false;
+       ENTRY;
+
+       child = lfsck_object_find_by_dev(env, dev, &ent->lde_fid);
+       if (IS_ERR(child))
+               RETURN(PTR_ERR(child));
+
+       LASSERT(dt_object_exists(child));
+       LASSERT(!dt_object_remote(child));
+
+       fid_cpu_to_be(key, &ent->lde_fid);
+       rc = dt_lookup(env, obj, (struct dt_rec *)&flags,
+                      (const struct dt_key *)key, BYPASS_CAPA);
+       if (rc == 0) {
+               exist = true;
+               flags |= LNTF_CHECK_ORPHAN;
+       } else if (rc == -ENOENT) {
+               flags = LNTF_CHECK_ORPHAN;
+       } else {
+               GOTO(out, rc);
+       }
+
+       th = dt_trans_create(env, dev);
+       if (IS_ERR(th))
+               GOTO(out, rc = PTR_ERR(th));
+
+       /* a1. remove name entry from backend /lost+found */
+       rc = dt_declare_delete(env, parent,
+                              (const struct dt_key *)ent->lde_name, th);
+       if (rc != 0)
+               GOTO(stop, rc);
+
+       if (S_ISDIR(lfsck_object_type(child))) {
+               /* a2. decrease parent's nlink */
+               rc = dt_declare_ref_del(env, parent, th);
+               if (rc != 0)
+                       GOTO(stop, rc);
+       }
+
+       if (exist) {
+               /* a3. remove child's FID from the LFSCK trace file. */
+               rc = dt_declare_delete(env, obj,
+                                      (const struct dt_key *)key, th);
+               if (rc != 0)
+                       GOTO(stop, rc);
+       } else {
+               /* a4. set child's ctime as 1 */
+               memset(la, 0, sizeof(*la));
+               la->la_ctime = 1;
+               la->la_valid = LA_CTIME;
+               rc = dt_declare_attr_set(env, child, la, th);
+               if (rc != 0)
+                       GOTO(stop, rc);
+       }
+
+       /* a5. insert child's FID into the LFSCK trace file. */
+       rc = dt_declare_insert(env, obj, (const struct dt_rec *)&flags,
+                              (const struct dt_key *)key, th);
+       if (rc != 0)
+               GOTO(stop, rc);
+
+       rc = dt_trans_start_local(env, dev, th);
+       if (rc != 0)
+               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);
+       if (rc != 0)
+               GOTO(stop, rc);
+
+       if (S_ISDIR(lfsck_object_type(child))) {
+               /* b2. decrease parent's nlink */
+               dt_write_lock(env, parent, 0);
+               rc = dt_ref_del(env, parent, th);
+               dt_write_unlock(env, parent);
+               if (rc != 0)
+                       GOTO(stop, rc);
+       }
+
+       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);
+               if (rc != 0)
+                       GOTO(stop, rc);
+       } else {
+               /* b4. set child's ctime as 1 */
+               rc = dt_attr_set(env, child, la, th, BYPASS_CAPA);
+               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);
+
+       GOTO(stop, rc = (rc == 0 ? 1 : rc));
+
+stop:
+       dt_trans_stop(env, dev, th);
+
+out:
+       lu_object_put(env, &child->do_lu);
+
+       return rc;
+}
+
+/**
+ * Handle orphans under the backend /lost+found directory
+ *
+ * Some backend checker, such as e2fsck for ldiskfs may find some orphans
+ * and put them under the backend /lost+found directory that is invisible
+ * to client. The LFSCK will scan such directory, for the original client
+ * visible orphans, add their fids into the namespace LFSCK trace file,
+ * then the subsenquent namespace LFSCK second-stage scanning can handle
+ * them as other objects to be double scanned: either move back to normal
+ * namespace, or to the global visible orphan directory:
+ * /ROOT/.lustre/lost+found/MDTxxxx/
+ *
+ * \param[in] env      pointer to the thread context
+ * \param[in] com      pointer to the lfsck component
+ */
+static void lfsck_namespace_scan_local_lpf(const struct lu_env *env,
+                                          struct lfsck_component *com)
+{
+       struct lfsck_thread_info        *info   = lfsck_env_info(env);
+       struct lu_dirent                *ent    =
+                                       (struct lu_dirent *)info->lti_key;
+       struct lu_seq_range             *range  = &info->lti_range;
+       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);
+       __u64                            cookie;
+       int                              rc     = 0;
+       __u16                            type;
+       ENTRY;
+
+       parent = lfsck_object_find_by_dev(env, dev, &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));
+               RETURN_EXIT;
+       }
+
+       /* It is normal that the /lost+found does not exist for ZFS backend. */
+       if (!dt_object_exists(parent))
+               GOTO(out, rc = 0);
+
+       if (unlikely(!dt_try_as_dir(env, parent)))
+               GOTO(out, rc = -ENOTDIR);
+
+       CDEBUG(D_LFSCK, "%s: start to scan backend /lost+found\n",
+              lfsck_lfsck2name(lfsck));
+
+       com->lc_new_scanned = 0;
+       iops = &parent->do_index_ops->dio_it;
+       di = iops->init(env, parent, LUDA_64BITHASH | LUDA_TYPE, BYPASS_CAPA);
+       if (IS_ERR(di))
+               GOTO(out, rc = PTR_ERR(di));
+
+       rc = iops->load(env, di, 0);
+       if (rc == 0)
+               rc = iops->next(env, di);
+       else if (rc > 0)
+               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;
+               }
+
+               rc = iops->rec(env, di, (struct dt_rec *)ent,
+                              LUDA_64BITHASH | LUDA_TYPE);
+               if (rc == 0)
+                       rc = lfsck_unpack_ent(ent, &cookie, &type);
+
+               if (unlikely(rc != 0)) {
+                       CDEBUG(D_LFSCK, "%s: fail to iterate backend "
+                              "/lost+found: rc = %d\n",
+                              lfsck_lfsck2name(lfsck), rc);
+
+                       goto skip;
+               }
+
+               /* skip dot and dotdot entries */
+               if (name_is_dot_or_dotdot(ent->lde_name, ent->lde_namelen))
+                       goto next;
+
+               if (!fid_seq_in_fldb(fid_seq(&ent->lde_fid)))
+                       goto skip;
+
+               if (fid_is_norm(&ent->lde_fid)) {
+                       fld_range_set_mdt(range);
+                       rc = fld_local_lookup(env, ss->ss_server_fld,
+                                             fid_seq(&ent->lde_fid), range);
+                       if (rc != 0)
+                               goto skip;
+               } else if (lfsck_dev_idx(dev) != 0) {
+                       /* If the returned FID is IGIF, then there are three
+                        * possible cases:
+                        *
+                        * 1) The object is upgraded from old Lustre-1.8 with
+                        *    IGIF assigned to such object.
+                        * 2) The object is a backend local object and is
+                        *    invisible to client.
+                        * 3) The object lost its LMV EA, and since there is
+                        *    no FID-in-dirent for the orphan in the backend
+                        *    /lost+found directory, then the low layer will
+                        *    return IGIF for such object.
+                        *
+                        * For MDTx (x != 0), it is either case 2) or case 3),
+                        * but from the LFSCK view, they are indistinguishable.
+                        * To be safe, the LFSCK will keep it there and report
+                        * some message, then the adminstrator can handle that
+                        * furtherly.
+                        *
+                        * For MDT0, it is more possible the case 1). The LFSCK
+                        * will handle the orphan as an upgraded object. */
+                       CDEBUG(D_LFSCK, "%s: the orphan %.*s with IGIF "DFID
+                              "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));
+                       goto skip;
+               }
+
+               rc = lfsck_namespace_scan_local_lpf_one(env, com, parent, ent);
+
+skip:
+               down_write(&com->lc_sem);
+               com->lc_new_scanned++;
+               ns->ln_local_lpf_scanned++;
+               if (rc > 0)
+                       ns->ln_local_lpf_moved++;
+               else if (rc == 0)
+                       ns->ln_local_lpf_skipped++;
+               else
+                       ns->ln_local_lpf_failed++;
+               up_write(&com->lc_sem);
+
+               if (rc < 0 && bk->lb_param & LPF_FAILOUT)
+                       break;
+
+next:
+               lfsck_control_speed_by_self(com);
+               if (unlikely(!thread_is_running(thread))) {
+                       rc = 0;
+                       break;
+               }
+
+               rc = iops->next(env, di);
+       }
+
+       iops->put(env, di);
+       iops->fini(env, di);
+
+       EXIT;
+
+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);
+}
+
+/**
+ * Rescan the striped directory after the master LMV EA reset.
+ *
+ * Sometimes, the master LMV EA of the striped directory maybe lost, so when
+ * the namespace LFSCK engine scan the striped directory for the first time,
+ * it will be regarded as a normal directory. As the LFSCK processing, some
+ * other LFSCK instance on other MDT will find the shard of this striped dir,
+ * and find that the master MDT-object of the striped directory lost its LMV
+ * EA, then such remote LFSCK instance will regenerate the master LMV EA and
+ * notify the LFSCK instance on this MDT to rescan the striped directory.
+ *
+ * \param[in] env      pointer to the thread context
+ * \param[in] com      pointer to the lfsck component
+ * \param[in] llu      the lfsck_lmv_unit that contains the striped directory
+ *                     to be rescanned.
+ *
+ * \retval             positive number for success
+ * \retval             0 for LFSCK stopped/paused
+ * \retval             negative error number on failure
+ */
+static int lfsck_namespace_rescan_striped_dir(const struct lu_env *env,
+                                             struct lfsck_component *com,
+                                             struct lfsck_lmv_unit *llu)
+{
+       struct lfsck_thread_info        *info   = lfsck_env_info(env);
+       struct lfsck_instance           *lfsck  = com->lc_lfsck;
+       struct lfsck_assistant_data     *lad    = com->lc_data;
+       struct dt_object                *dir;
+       const struct dt_it_ops          *iops;
+       struct dt_it                    *di;
+       struct lu_dirent                *ent    =
+                       (struct lu_dirent *)info->lti_key;
+       struct lfsck_bookmark           *bk     = &lfsck->li_bookmark_ram;
+       struct ptlrpc_thread            *thread = &lfsck->li_thread;
+       struct lfsck_namespace_req      *lnr;
+       struct lfsck_assistant_req      *lar;
+       int                              rc;
+       __u16                            type;
+       ENTRY;
+
+       LASSERT(list_empty(&lad->lad_req_list));
+
+       lfsck->li_lmv = &llu->llu_lmv;
+       lfsck->li_obj_dir = lfsck_object_get(llu->llu_obj);
+       rc = lfsck_open_dir(env, lfsck, 0);
+       if (rc != 0)
+               RETURN(rc);
+
+       dir = lfsck->li_obj_dir;
+       di = lfsck->li_di_dir;
+       iops = &dir->do_index_ops->dio_it;
+       do {
+               rc = iops->rec(env, di, (struct dt_rec *)ent,
+                              lfsck->li_args_dir);
+               if (rc == 0)
+                       rc = lfsck_unpack_ent(ent, &lfsck->li_cookie_dir,
+                                             &type);
+
+               if (rc != 0) {
+                       if (bk->lb_param & LPF_FAILOUT)
+                               GOTO(out, rc);
+
+                       goto next;
+               }
+
+               if (name_is_dot_or_dotdot(ent->lde_name, ent->lde_namelen))
+                       goto next;
+
+               lnr = lfsck_namespace_assistant_req_init(lfsck, ent, type);
+               if (IS_ERR(lnr)) {
+                       if (bk->lb_param & LPF_FAILOUT)
+                               GOTO(out, rc = PTR_ERR(lnr));
+
+                       goto next;
+               }
+
+               lar = &lnr->lnr_lar;
+               rc = lfsck_namespace_assistant_handler_p1(env, com, lar);
+               lfsck_namespace_assistant_req_fini(env, lar);
+               if (rc != 0 && bk->lb_param & LPF_FAILOUT)
+                       GOTO(out, rc);
+
+               if (unlikely(!thread_is_running(thread)))
+                       GOTO(out, rc = 0);
+
+next:
+               rc = iops->next(env, di);
+       } while (rc == 0);
+
+out:
+       lfsck_close_dir(env, lfsck, rc);
+       if (rc <= 0)
+               RETURN(rc);
+
+       /* The close_dir() may insert a dummy lnr in the lad->lad_req_list. */
+       if (list_empty(&lad->lad_req_list))
+               RETURN(1);
+
+       spin_lock(&lad->lad_lock);
+       lar = list_entry(lad->lad_req_list.next, struct lfsck_assistant_req,
+                         lar_list);
+       list_del_init(&lar->lar_list);
+       spin_unlock(&lad->lad_lock);
+
+       rc = lfsck_namespace_assistant_handler_p1(env, com, lar);
+       lfsck_namespace_assistant_req_fini(env, lar);
+
+       RETURN(rc == 0 ? 1 : rc);
+}
+
 static int lfsck_namespace_assistant_handler_p2(const struct lu_env *env,
                                                struct lfsck_component *com)
 {
@@ -4671,9 +5906,25 @@ 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();
@@ -4716,7 +5967,7 @@ static int lfsck_namespace_assistant_handler_p2(const struct lu_env *env,
                        goto checkpoint;
                }
 
-               target = lfsck_object_find(env, lfsck, &fid);
+               target = lfsck_object_find_by_dev(env, lfsck->li_bottom, &fid);
                if (IS_ERR(target)) {
                        rc = PTR_ERR(target);
                        goto checkpoint;
@@ -4758,7 +6009,7 @@ 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);
@@ -4832,14 +6083,15 @@ static int lfsck_namespace_double_scan_result(const struct lu_env *env,
                ns->ln_time_last_complete = ns->ln_time_last_checkpoint;
                ns->ln_success_count++;
        } else if (rc == 0) {
-               ns->ln_status = lfsck->li_status;
-               if (ns->ln_status == 0)
+               if (lfsck->li_status != 0)
+                       ns->ln_status = lfsck->li_status;
+               else
                        ns->ln_status = LS_STOPPED;
        } else {
                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;
@@ -4937,7 +6189,7 @@ out:
        if (rc != 0)
                CDEBUG(D_LFSCK, "%s: namespace LFSCK assistant fail "
                       "to sync failure with MDTs, and related MDTs "
-                      "may handle orphan un-properly: rc = %d\n",
+                      "may handle orphan improperly: rc = %d\n",
                       lfsck_lfsck2name(lfsck), rc);
 
        EXIT;
@@ -5290,10 +6542,10 @@ int lfsck_namespace_setup(const struct lu_env *env,
                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);
        if (rc != 0)
                GOTO(out, rc);