+/**
+ * Retrieve fldb entry from MDT0 and add to local FLDB and cache.
+ **/
+int fld_update_from_controller(const struct lu_env *env,
+ struct lu_server_fld *fld)
+{
+ struct fld_thread_info *info;
+ struct lu_seq_range *range;
+ struct lu_seq_range_array *lsra;
+ __u32 index;
+ struct ptlrpc_request *req;
+ int rc;
+ int i;
+ ENTRY;
+
+ /* Update only happens during initalization, i.e. local FLDB
+ * does not exist yet */
+ if (!fld->lsf_new)
+ RETURN(0);
+
+ rc = fld_name_to_index(fld->lsf_name, &index);
+ if (rc < 0)
+ RETURN(rc);
+
+ /* No need update fldb for MDT0 */
+ if (index == 0)
+ RETURN(0);
+
+ info = lu_context_key_get(&env->le_ctx, &fld_thread_key);
+ LASSERT(info != NULL);
+ range = &info->fti_lrange;
+ memset(range, 0, sizeof(*range));
+ range->lsr_index = index;
+ fld_range_set_mdt(range);
+
+ do {
+ rc = fld_client_rpc(fld->lsf_control_exp, range, FLD_READ,
+ &req);
+ if (rc != 0 && rc != -EAGAIN)
+ GOTO(out, rc);
+
+ LASSERT(req != NULL);
+ lsra = (struct lu_seq_range_array *)req_capsule_server_get(
+ &req->rq_pill, &RMF_GENERIC_DATA);
+ if (lsra == NULL)
+ GOTO(out, rc = -EPROTO);
+
+ range_array_le_to_cpu(lsra, lsra);
+ for (i = 0; i < lsra->lsra_count; i++) {
+ int rc1;
+
+ if (lsra->lsra_lsr[i].lsr_flags != LU_SEQ_RANGE_MDT)
+ GOTO(out, rc = -EINVAL);
+
+ if (lsra->lsra_lsr[i].lsr_index != index)
+ GOTO(out, rc = -EINVAL);
+
+ mutex_lock(&fld->lsf_lock);
+ rc1 = fld_insert_entry(env, fld, &lsra->lsra_lsr[i]);
+ mutex_unlock(&fld->lsf_lock);
+
+ if (rc1 != 0)
+ GOTO(out, rc = rc1);
+ }
+ if (rc == -EAGAIN)
+ *range = lsra->lsra_lsr[lsra->lsra_count - 1];
+ } while (rc == -EAGAIN);
+
+ fld->lsf_new = 1;