Re: [PATCH v2] libata: Simulate REPORT LUNS for ATAPI devices

From: Patrick Mansfield
Date: Wed Dec 13 2006 - 13:57:14 EST


On Mon, Dec 04, 2006 at 03:32:20PM -0800, Darrick J. Wong wrote:
> The Quantum GoVault SATAPI removable disk device returns ATA_ERR in
> response to a REPORT LUNS packet. If this happens to an ATAPI device
> that is attached to a SAS controller (this is the case with sas_ata),
> the device does not load because SCSI won't touch a "SCSI device"
> that won't report its LUNs. Since most ATAPI devices don't support
> multiple LUNs anyway, we might as well fake a response like we do for
> ATA devices.

If the REPORT LUNS fails, we should fall back to a sequential scan.

Is (or why isn't) the error propagated back to scsi?

> Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx>
> ---
>
> drivers/ata/libata-scsi.c | 9 +++++++--
> 1 files changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
> index 47ea111..5ecf260 100644
> --- a/drivers/ata/libata-scsi.c
> +++ b/drivers/ata/libata-scsi.c
> @@ -2833,8 +2833,13 @@ static inline int __ata_scsi_queuecmd(st
> rc = ata_scsi_translate(dev, cmd, done, xlat_func);
> else
> ata_scsi_simulate(dev, cmd, done);
> - } else
> - rc = ata_scsi_translate(dev, cmd, done, atapi_xlat);
> + } else {
> + /* Simulate REPORT LUNS for ATAPI devices */
> + if (cmd->cmnd[0] == REPORT_LUNS)
> + ata_scsi_simulate(dev, cmd, done);
> + else
> + rc = ata_scsi_translate(dev, cmd, done, atapi_xlat);
> + }
>
> return rc;
> }

-- Patrick Mansfield
-
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