scsi: zfcp: Move fc_host updates during xport data handling into fenced function

When executing exchange port data for a FCP device for the first time, or
after an adapter recovery, we update several properties of the fibre
channel host object which represents that FCP device.

When moving the scsi host object allocation and registration - and thus
also the fibre channel host object allocation - to after the first exchange
config and exchange port data, this is not possible for the former case.

Move all these update into separate, and fenced function that first checks
whether the scsi host object already exists or not, before making the
updates.

During the first ever exchange port data in the adapter life cycle this
will make the exchange port data handler skip over this update step, but we
can repeat it later, after we allocated the scsi host object.

For any further recovery of that adapter the work flow is only changed
slightly because then the scsi host object already exists and we don't free
it until we release the adapter completely at the end of its life cycle.

Link: https://lore.kernel.org/r/ae454c2dc6da0b02907c489af91d0b211d331825.1588956679.git.bblock@linux.ibm.comReviewed-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/s390/scsi/zfcp_ext.h

@@ -176,6 +176,9 @@ extern void zfcp_scsi_shost_update_config_data(
 	struct zfcp_adapter *const adapter,
 	const struct fsf_qtcb_bottom_config *const bottom,
 	const bool bottom_incomplete);
+extern void zfcp_scsi_shost_update_port_data(
+	struct zfcp_adapter *const adapter,
+	const struct fsf_qtcb_bottom_port *const bottom);
 
 /* zfcp_sysfs.c */
 extern const struct attribute_group *zfcp_unit_attr_groups[];

drivers/s390/scsi/zfcp_fsf.c

@@ -725,19 +725,10 @@ static void zfcp_fsf_exchange_port_evaluate(struct zfcp_fsf_req *req)
 {
 	struct zfcp_adapter *adapter = req->adapter;
 	struct fsf_qtcb_bottom_port *bottom = &req->qtcb->bottom.port;
-	struct Scsi_Host *shost = adapter->scsi_host;
 
 	if (req->data)
 		memcpy(req->data, bottom, sizeof(*bottom));
 
-	fc_host_permanent_port_name(shost) = bottom->wwpn;
-	fc_host_maxframe_size(shost) = bottom->maximum_frame_size;
-	fc_host_supported_speeds(shost) =
-		zfcp_fsf_convert_portspeed(bottom->supported_speed);
-	memcpy(fc_host_supported_fc4s(shost), bottom->supported_fc4_types,
-	       FC_FC4_LIST_SIZE);
-	memcpy(fc_host_active_fc4s(shost), bottom->active_fc4_types,
-	       FC_FC4_LIST_SIZE);
 	if (adapter->adapter_features & FSF_FEATURE_FC_SECURITY)
 		adapter->fc_security_algorithms =
 			bottom->fc_security_algorithms;
@@ -764,6 +755,7 @@ static void zfcp_fsf_exchange_port_data_handler(struct zfcp_fsf_req *req)
 		 */
 		zfcp_diag_update_xdata(diag_hdr, bottom, false);
 
+		zfcp_scsi_shost_update_port_data(req->adapter, bottom);
 		zfcp_fsf_exchange_port_evaluate(req);
 		break;
 	case FSF_EXCHANGE_CONFIG_DATA_INCOMPLETE:
@@ -772,6 +764,8 @@ static void zfcp_fsf_exchange_port_data_handler(struct zfcp_fsf_req *req)
 
 		zfcp_fsf_link_down_info_eval(req,
 			&qtcb->header.fsf_status_qual.link_down_info);
+
+		zfcp_scsi_shost_update_port_data(req->adapter, bottom);
 		zfcp_fsf_exchange_port_evaluate(req);
 		break;
 	}

drivers/s390/scsi/zfcp_scsi.c

@@ -911,6 +911,25 @@ void zfcp_scsi_shost_update_config_data(
 	}
 }
 
+void zfcp_scsi_shost_update_port_data(
+	struct zfcp_adapter *const adapter,
+	const struct fsf_qtcb_bottom_port *const bottom)
+{
+	struct Scsi_Host *const shost = adapter->scsi_host;
+
+	if (shost == NULL)
+		return;
+
+	fc_host_permanent_port_name(shost) = bottom->wwpn;
+	fc_host_maxframe_size(shost) = bottom->maximum_frame_size;
+	fc_host_supported_speeds(shost) =
+		zfcp_fsf_convert_portspeed(bottom->supported_speed);
+	memcpy(fc_host_supported_fc4s(shost), bottom->supported_fc4_types,
+	       FC_FC4_LIST_SIZE);
+	memcpy(fc_host_active_fc4s(shost), bottom->active_fc4_types,
+	       FC_FC4_LIST_SIZE);
+}
+
 struct fc_function_template zfcp_transport_functions = {
 	.show_starget_port_id = 1,
 	.show_starget_port_name = 1,