[SCSI] qla2xxx: Correct synchronization of software/firmware fcport states.

Greg Wettstein ([e-mail]) noted:

http://article.gmane.org/gmane.linux.scsi/43409

on a reboot of a previously recognized SCST target, the initiator
driver would be unable to re-recognize the device as a target.
It turns out that prior to the SCST software reloading and
returning it's "target-capable" abilities in the PRLI payload,
the HBA would be re-initialized as an initiator-only type port.
Since initiators typically classify themselves as an FCP-2
capable device, both software and firmware do not perform an
explicit logout during port-loss. Unfortunately, as can be seen
by the failure case, when the port (now target-capable) returns,
firmware performs an ADISC without a follow-on PRLI, leaving
stale 'initiator-only' data in the firmware's port database.

Correct the discrepancy by performing the explicit logout during
the transport's request to terminate-rport-io, thus synchronizing
port states and ensuring a follow-on PRLI is performed.

Reported-by: Greg Wettstein <[e-mail]>
Signed-off-by: Andrew Vasquez <[e-mail]>
Cc: Stable Tree <[e-mail]>
Signed-off-by: James Bottomley <[e-mail]>

drivers/scsi/qla2xxx/qla_attr.c

···
 {
 	fc_port_t *fcport = *(fc_port_t **)rport->dd_data;
 
+	/*
+	 * At this point all fcport's software-states are cleared.  Perform any
+	 * final cleanup of firmware resources (PCBs and XCBs).
+	 */
+	if (fcport->loop_id != FC_NO_LOOP_ID) {
+		fcport->ha->isp_ops->fabric_logout(fcport->ha, fcport->loop_id,
+		    fcport->d_id.b.domain, fcport->d_id.b.area,
+		    fcport->d_id.b.al_pa);
+		fcport->loop_id = FC_NO_LOOP_ID;
+	}
+
 	qla2x00_abort_fcport_cmds(fcport);
 	scsi_target_unblock(&rport->dev);
 }