+LPROC_SEQ_FOPS(ldiskfs_osd_readcache);
+
+#if LUSTRE_VERSION_CODE < OBD_OCD_VERSION(3, 0, 52, 0)
+static int ldiskfs_osd_index_in_idif_seq_show(struct seq_file *m, void *data)
+{
+ struct osd_device *dev = osd_dt_dev((struct dt_device *)m->private);
+
+ LASSERT(dev != NULL);
+ if (unlikely(dev->od_mnt == NULL))
+ return -EINPROGRESS;
+
+ seq_printf(m, "%d\n", (int)(dev->od_index_in_idif));
+ return 0;
+}
+
+static ssize_t
+ldiskfs_osd_index_in_idif_seq_write(struct file *file,
+ const char __user *buffer,
+ size_t count, loff_t *off)
+{
+ struct lu_env env;
+ struct seq_file *m = file->private_data;
+ struct dt_device *dt = m->private;
+ struct osd_device *dev = osd_dt_dev(dt);
+ struct lu_target *tgt;
+ __s64 val;
+ int rc;
+
+ LASSERT(dev != NULL);
+ if (unlikely(dev->od_mnt == NULL))
+ return -EINPROGRESS;
+
+ rc = lprocfs_str_to_s64(buffer, count, &val);
+ if (rc != 0)
+ return rc;
+
+ if (dev->od_index_in_idif) {
+ if (val != 0)
+ return count;
+
+ LCONSOLE_WARN("%s: OST-index in IDIF has been enabled, "
+ "it cannot be reverted back.\n", osd_name(dev));
+ return -EPERM;
+ }
+
+ if (val == 0)
+ return count;
+
+ rc = lu_env_init(&env, LCT_DT_THREAD);
+ if (rc != 0)
+ return rc;
+
+ tgt = dev->od_dt_dev.dd_lu_dev.ld_site->ls_tgt;
+ tgt->lut_lsd.lsd_feature_rocompat |= OBD_ROCOMPAT_IDX_IN_IDIF;
+ rc = tgt_server_data_update(&env, tgt, 1);
+ lu_env_fini(&env);
+ if (rc < 0)
+ return rc;
+
+ LCONSOLE_INFO("%s: enable OST-index in IDIF successfully, "
+ "it cannot be reverted back.\n", osd_name(dev));
+
+ dev->od_index_in_idif = 1;
+ return count;
+}
+LPROC_SEQ_FOPS(ldiskfs_osd_index_in_idif);
+
+int osd_register_proc_index_in_idif(struct osd_device *osd)
+{
+ struct proc_dir_entry *proc;
+
+ proc = proc_create_data("index_in_idif", 0, osd->od_proc_entry,
+ &ldiskfs_osd_index_in_idif_fops,
+ &osd->od_dt_dev);
+ if (proc == NULL)
+ return -ENOMEM;
+
+ return 0;
+}
+#endif
+
+LPROC_SEQ_FOPS_RO_TYPE(ldiskfs, dt_blksize);
+LPROC_SEQ_FOPS_RO_TYPE(ldiskfs, dt_kbytestotal);
+LPROC_SEQ_FOPS_RO_TYPE(ldiskfs, dt_kbytesfree);
+LPROC_SEQ_FOPS_RO_TYPE(ldiskfs, dt_kbytesavail);
+LPROC_SEQ_FOPS_RO_TYPE(ldiskfs, dt_filestotal);
+LPROC_SEQ_FOPS_RO_TYPE(ldiskfs, dt_filesfree);