diff options
| author | Alan Stern <stern@rowland.harvard.edu> | 2007-01-08 16:18:05 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2007-02-07 15:44:35 -0800 |
| commit | f3f4906516a084bbd9aa3da7592e6b029fe78f5b (patch) | |
| tree | 129dbc126c9728c55c90159d3038adf7db9ccd11 /drivers/usb | |
| parent | 85a975d0ce48dfa8dec5bf1bd970f8fd2c48af32 (diff) | |
usb-storage: SCSI level fixes
This patch (as835) removes from usb-storage the code which sets all
devices to a SCSI level of at least SCSI-2. The original reasons for
doing this no longer apply, and in fact it prevents certain kinds of
ATA pass-thru commands from being used.
The patch also marks CB and CBI devices that are SCSI-0 (legacy SCSI)
as being single-LUN, since the combined SCSI-over-USB transport
protocol has no way to convey LUN information to these devices.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Matthew Dharm <mdharm-usb@one-eyed-alien.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/usb')
| -rw-r--r-- | drivers/usb/storage/scsiglue.c | 31 |
1 files changed, 13 insertions, 18 deletions
diff --git a/drivers/usb/storage/scsiglue.c b/drivers/usb/storage/scsiglue.c index e1072d52d641..70234f5dbeeb 100644 --- a/drivers/usb/storage/scsiglue.c +++ b/drivers/usb/storage/scsiglue.c @@ -110,23 +110,6 @@ static int slave_configure(struct scsi_device *sdev) * the end, scatter-gather buffers follow page boundaries. */ blk_queue_dma_alignment(sdev->request_queue, (512 - 1)); - /* Set the SCSI level to at least 2. We'll leave it at 3 if that's - * what is originally reported. We need this to avoid confusing - * the SCSI layer with devices that report 0 or 1, but need 10-byte - * commands (ala ATAPI devices behind certain bridges, or devices - * which simply have broken INQUIRY data). - * - * NOTE: This means /dev/sg programs (ala cdrecord) will get the - * actual information. This seems to be the preference for - * programs like that. - * - * NOTE: This also means that /proc/scsi/scsi and sysfs may report - * the actual value or the modified one, depending on where the - * data comes from. - */ - if (sdev->scsi_level < SCSI_2) - sdev->scsi_level = sdev->sdev_target->scsi_level = SCSI_2; - /* Many devices have trouble transfering more than 32KB at a time, * while others have trouble with more than 64K. At this time we * are limiting both to 32K (64 sectores). @@ -176,7 +159,9 @@ static int slave_configure(struct scsi_device *sdev) * 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 = sdev->sdev_target->scsi_level = SCSI_2; + if (sdev->scsi_level > SCSI_2) + sdev->sdev_target->scsi_level = + sdev->scsi_level = SCSI_2; /* USB-IDE bridges tend to report SK = 0x04 (Non-recoverable * Hardware Error) when any low-level error occurs, @@ -194,6 +179,16 @@ static int slave_configure(struct scsi_device *sdev) sdev->use_10_for_ms = 1; } + /* The CB and CBI transports have no way to pass LUN values + * other than the bits in the second byte of a CDB. But those + * bits don't get set to the LUN value if the device reports + * scsi_level == 0 (UNKNOWN). Hence such devices must necessarily + * be single-LUN. + */ + if ((us->protocol == US_PR_CB || us->protocol == US_PR_CBI) && + sdev->scsi_level == SCSI_UNKNOWN) + us->max_lun = 0; + /* Some devices choke when they receive a PREVENT-ALLOW MEDIUM * REMOVAL command, so suppress those commands. */ if (us->flags & US_FL_NOT_LOCKABLE) |