[SCSI] zfcp: Fix opening of wka ports

Running two wka_port_get calls in parallel could issue two open_port
requests, overwriting the port handle. Don't issue an open_port
for the state PORT_OPENING, and only read the data from GOOD
responses.
Signed-off-by: NChristof Schmitt <christof.schmitt@de.ibm.com>
Acked-by: NSwen Schillig <swen@vnet.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

drivers/s390/scsi/zfcp_fc.c

@@ -50,7 +50,8 @@ static int zfcp_wka_port_get(struct zfcp_wka_port *wka_port)
 	if (mutex_lock_interruptible(&wka_port->mutex))
 		return -ERESTARTSYS;
 
-	if (wka_port->status != ZFCP_WKA_PORT_ONLINE) {
+	if (wka_port->status == ZFCP_WKA_PORT_OFFLINE ||
+	    wka_port->status == ZFCP_WKA_PORT_CLOSING) {
 		wka_port->status = ZFCP_WKA_PORT_OPENING;
 		if (zfcp_fsf_open_wka_port(wka_port))
 			wka_port->status = ZFCP_WKA_PORT_OFFLINE;

drivers/s390/scsi/zfcp_fsf.c

@@ -1584,6 +1584,7 @@ static void zfcp_fsf_open_wka_port_handler(struct zfcp_fsf_req *req)
 		wka_port->status = ZFCP_WKA_PORT_OFFLINE;
 		break;
 	case FSF_PORT_ALREADY_OPEN:
+		break;
 	case FSF_GOOD:
 		wka_port->handle = header->port_handle;
 		wka_port->status = ZFCP_WKA_PORT_ONLINE;