[SCSI] qla2xxx: Stall mid-layer error handlers while rport is blocked.

Stall error handler if attempting recovery while an rport is
blocked.  This avoids device offline scenarios due to errors in
the error handler.

Reference implementation from lpfc/mptfc.
Signed-off-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

drivers/scsi/qla2xxx/qla_os.c

@@ -589,6 +589,23 @@ qla2x00_wait_for_loop_ready(scsi_qla_host_t *ha)
 	return (return_status);
 }
 
+static void
+qla2x00_block_error_handler(struct scsi_cmnd *cmnd)
+{
+	struct Scsi_Host *shost = cmnd->device->host;
+	struct fc_rport *rport = starget_to_rport(scsi_target(cmnd->device));
+	unsigned long flags;
+
+	spin_lock_irqsave(shost->host_lock, flags);
+	while (rport->port_state == FC_PORTSTATE_BLOCKED) {
+		spin_unlock_irqrestore(shost->host_lock, flags);
+		msleep(1000);
+		spin_lock_irqsave(shost->host_lock, flags);
+	}
+	spin_unlock_irqrestore(shost->host_lock, flags);
+	return;
+}
+
 /**************************************************************************
 * qla2xxx_eh_abort
 *
@@ -615,6 +632,8 @@ qla2xxx_eh_abort(struct scsi_cmnd *cmd)
 	unsigned long flags;
 	int wait = 0;
 
+	qla2x00_block_error_handler(cmd);
+
 	if (!CMD_SP(cmd))
 		return SUCCESS;
 
@@ -748,6 +767,8 @@ qla2xxx_eh_device_reset(struct scsi_cmnd *cmd)
 	unsigned int id, lun;
 	unsigned long serial;
 
+	qla2x00_block_error_handler(cmd);
+
 	ret = FAILED;
 
 	id = cmd->device->id;
@@ -877,6 +898,8 @@ qla2xxx_eh_bus_reset(struct scsi_cmnd *cmd)
 	unsigned int id, lun;
 	unsigned long serial;
 
+	qla2x00_block_error_handler(cmd);
+
 	ret = FAILED;
 
 	id = cmd->device->id;
@@ -936,6 +959,8 @@ qla2xxx_eh_host_reset(struct scsi_cmnd *cmd)
 	unsigned int id, lun;
 	unsigned long serial;
 
+	qla2x00_block_error_handler(cmd);
+
 	ret = FAILED;
 
 	id = cmd->device->id;