diff --git a/drivers/s390/scsi/zfcp_aux.c b/drivers/s390/scsi/zfcp_aux.c
index 68df57157d48b8..5c4b874591ea54 100644
--- a/drivers/s390/scsi/zfcp_aux.c
+++ b/drivers/s390/scsi/zfcp_aux.c
@@ -159,6 +159,9 @@ static int __init zfcp_module_init(void)
 		fc_attach_transport(&zfcp_transport_functions);
 	if (!zfcp_data.scsi_transport_template)
 		goto out_transport;
+	scsi_transport_reserve_device(zfcp_data.scsi_transport_template,
+				      sizeof(struct zfcp_scsi_dev));
+
 
 	retval = misc_register(&zfcp_cfdc_misc);
 	if (retval) {
diff --git a/drivers/s390/scsi/zfcp_def.h b/drivers/s390/scsi/zfcp_def.h
index e1c6b6e05a75ea..d31158c0de937e 100644
--- a/drivers/s390/scsi/zfcp_def.h
+++ b/drivers/s390/scsi/zfcp_def.h
@@ -233,6 +233,45 @@ struct zfcp_unit {
 	struct work_struct	scsi_work;
 };
 
+/**
+ * struct zfcp_scsi_dev - zfcp data per SCSI device
+ * @status: zfcp internal status flags
+ * @lun_handle: handle from "open lun" for issuing FSF requests
+ * @erp_action: zfcp erp data for opening and recovering this LUN
+ * @erp_counter: zfcp erp counter for this LUN
+ * @latencies: FSF channel and fabric latencies
+ * @port: zfcp_port where this LUN belongs to
+ */
+struct zfcp_scsi_dev {
+	atomic_t		status;
+	u32			lun_handle;
+	struct zfcp_erp_action	erp_action;
+	atomic_t		erp_counter;
+	struct zfcp_latencies	latencies;
+	struct zfcp_port	*port;
+};
+
+/**
+ * sdev_to_zfcp - Access zfcp LUN data for SCSI device
+ * @sdev: scsi_device where to get the zfcp_scsi_dev pointer
+ */
+static inline struct zfcp_scsi_dev *sdev_to_zfcp(struct scsi_device *sdev)
+{
+	return scsi_transport_device_data(sdev);
+}
+
+/**
+ * zfcp_scsi_dev_lun - Return SCSI device LUN as 64 bit FCP LUN
+ * @sdev: SCSI device where to get the LUN from
+ */
+static inline u64 zfcp_scsi_dev_lun(struct scsi_device *sdev)
+{
+	u64 fcp_lun;
+
+	int_to_scsilun(sdev->lun, (struct scsi_lun *)&fcp_lun);
+	return fcp_lun;
+}
+
 /**
  * struct zfcp_fsf_req - basic FSF request structure
  * @list: list of FSF requests