[smartpqi updates PATCH V2 09/11] smartpqi: fix duplicate device nodes for tape changers

[Don Brace <don.brace@microchip.com>]

From: Kevin Barnett <kevin.barnett@microchip.com>

Stop the OS from re-discovering multiple LUNs for
tape drive and medium changer.

Duplicate device nodes for Ultrium tape drive and
medium changer are being created.

The Ultrium tape drive is a multi-LUN SCSI target.
It presents a LUN for the tape drive and a 2nd
LUN for the medium changer.
Our controller FW lists both LUNs in the RPL
results.

As a result, the smartpqi driver exposes both
devices to the OS. Then the OS does its normal
device discovery via the SCSI REPORT LUNS command,
which causes it to re-discover both devices a 2nd time,
which results in the duplicate device nodes.

Reviewed-by: Scott Benesh <scott.benesh@microchip.com>
Reviewed-by: Scott Teel <scott.teel@microchip.com>
Reviewed-by: Mike McGowen <mike.mcgowen@microchip.com>
Signed-off-by: Kevin Barnett <kevin.barnett@microchip.com>
Signed-off-by: Don Brace <don.brace@microchip.com>
---
 drivers/scsi/smartpqi/smartpqi.h      |  1 +
 drivers/scsi/smartpqi/smartpqi_init.c | 23 +++++++++++++++++++----
 2 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/drivers/scsi/smartpqi/smartpqi.h b/drivers/scsi/smartpqi/smartpqi.h
index c439583a4ca5..aac88ac0a0b7 100644
--- a/drivers/scsi/smartpqi/smartpqi.h
+++ b/drivers/scsi/smartpqi/smartpqi.h
@@ -1106,6 +1106,7 @@ struct pqi_scsi_dev {
 	u8	keep_device : 1;
 	u8	volume_offline : 1;
 	u8	rescan : 1;
+	u8	ignore_device : 1;
 	bool	aio_enabled;		/* only valid for physical disks */
 	bool	in_remove;
 	bool	device_offline;
diff --git a/drivers/scsi/smartpqi/smartpqi_init.c b/drivers/scsi/smartpqi/smartpqi_init.c
index c28eb7ea4a24..8be116992cb0 100644
--- a/drivers/scsi/smartpqi/smartpqi_init.c
+++ b/drivers/scsi/smartpqi/smartpqi_init.c
@@ -6297,9 +6297,13 @@ static int pqi_slave_alloc(struct scsi_device *sdev)
 		rphy = target_to_rphy(starget);
 		device = pqi_find_device_by_sas_rphy(ctrl_info, rphy);
 		if (device) {
-			device->target = sdev_id(sdev);
-			device->lun = sdev->lun;
-			device->target_lun_valid = true;
+			if (device->target_lun_valid) {
+				device->ignore_device = true;
+			} else {
+				device->target = sdev_id(sdev);
+				device->lun = sdev->lun;
+				device->target_lun_valid = true;
+			}
 		}
 	} else {
 		device = pqi_find_scsi_dev(ctrl_info, sdev_channel(sdev),
@@ -6336,14 +6340,25 @@ static int pqi_map_queues(struct Scsi_Host *shost)
 					ctrl_info->pci_dev, 0);
 }
 
+static inline bool pqi_is_tape_changer_device(struct pqi_scsi_dev *device)
+{
+	return device->devtype == TYPE_TAPE || device->devtype == TYPE_MEDIUM_CHANGER;
+}
+
 static int pqi_slave_configure(struct scsi_device *sdev)
 {
+	int rc = 0;
 	struct pqi_scsi_dev *device;
 
 	device = sdev->hostdata;
 	device->devtype = sdev->type;
 
-	return 0;
+	if (pqi_is_tape_changer_device(device) && device->ignore_device) {
+		rc = -ENXIO;
+		device->ignore_device = false;
+	}
+
+	return rc;
 }
 
 static int pqi_getpciinfo_ioctl(struct pqi_ctrl_info *ctrl_info, void __user *arg)
-- 
2.28.0.rc1.9.ge7ae437ac1