qla2xxx: disable scsi_transport_fc registration in target mode

There are multiple reasons for disabling this:

1. It provides no functional benefit. We pretty much only get a few more
sysfs entries for each port, but all that information is already
available from /sys/kernel/debug/target/qla-session-X

2. It already only works in private-loop mode. By disabling we'll be
getting more uniform behavior with fabric mode.

3. It creates complications for the new PLOGI handling mechanism:
scsi_transport_fc port deletion timer could race with new session
from initiator and cause logout after successful login.

Cc: <stable@vger.kernel.org> # v3.18+
Signed-off-by: Alexei Potashnik <alexei@purestorage.com>
Signed-off-by: Himanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

drivers/scsi/qla2xxx/qla_init.c

@@ -3340,8 +3340,7 @@ qla2x00_update_fcport(scsi_qla_host_t *vha, fc_port_t *fcport)
 
 	if (IS_QLAFX00(vha->hw)) {
 		qla2x00_set_fcport_state(fcport, FCS_ONLINE);
-		qla2x00_reg_remote_port(vha, fcport);
-		return;
+		goto reg_port;
 	}
 	fcport->login_retry = 0;
 	fcport->flags &= ~(FCF_LOGIN_NEEDED | FCF_ASYNC_SENT);
@@ -3349,7 +3348,16 @@ qla2x00_update_fcport(scsi_qla_host_t *vha, fc_port_t *fcport)
 	qla2x00_set_fcport_state(fcport, FCS_ONLINE);
 	qla2x00_iidma_fcport(vha, fcport);
 	qla24xx_update_fcport_fcp_prio(vha, fcport);
-	qla2x00_reg_remote_port(vha, fcport);
+
+reg_port:
+	if (qla_ini_mode_enabled(vha))
+		qla2x00_reg_remote_port(vha, fcport);
+	else {
+		/*
+		 * Create target mode FC NEXUS in qla_target.c
+		 */
+		qlt_fc_port_added(vha, fcport);
+	}
 }
 
 /*

drivers/scsi/qla2xxx/qla_os.c

@@ -3235,7 +3235,8 @@ qla2x00_schedule_rport_del(struct scsi_qla_host *vha, fc_port_t *fcport,
 		qla2xxx_wake_dpc(base_vha);
 	} else {
 		int now;
-		fc_remote_port_delete(rport);
+		if (rport)
+			fc_remote_port_delete(rport);
 		qlt_do_generation_tick(vha, &now);
 		qlt_fc_port_deleted(vha, fcport, now);
 	}