[PATCH] USB Storage: Force starget->scsi_level in usb-storage scsiglue.c

When the usb-storage module forces sdev->scsi_level to SCSI_2, it should
also force starget->scsi_level to the same value. Otherwise, the SCSI
layer may attempt to issue SCSI-3 commands to the device, such as REPORT
LUNS, which it cannot handle. This can prevent the device from working
with Linux.

The AMS Venus DS3 DS2316SU2S SATA-to-SATA+USB enclosure, based on the
Oxford Semiconductor OXU921S chip, requires this patch to function
correctly on Linux. The enclosure reports a SCSI-3 SPC-2 command set
level, but does not correctly handle the REPORT LUNS SCSI command -
probably due to a bug in its firmware.

It seems likely that other USB storage enclosures with similar bugs will
also benefit from this patch.

Tony Lindgren <[e-mail]> collaborated in the development of this
patch.

Signed-off-by: Paul Walmsley <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

drivers/usb/storage/scsiglue.c

···
 	 * data comes from.
 	 */
 	if (sdev->scsi_level < SCSI_2)
-		sdev->scsi_level = SCSI_2;
+		sdev->scsi_level = sdev->sdev_target->scsi_level = SCSI_2;
 
 	/* According to the technical support people at Genesys Logic,
 	 * devices using their chips have problems transferring more than
···
 		 * a Get-Max-LUN request, we won't lose much by setting the
 		 * revision level down to 2.  The only devices that would be
 		 * affected are those with sparse LUNs. */
-		sdev->scsi_level = SCSI_2;
+		sdev->scsi_level = sdev->sdev_target->scsi_level = SCSI_2;
 
 		/* USB-IDE bridges tend to report SK = 0x04 (Non-recoverable
 		 * Hardware Error) when any low-level error occurs,