Re: [PATCH v6 09/19] scsi: allow enabling and disabling command duration limits

Hannes Reinecke
2023-04-11T06:44:18Z

On 4/6/23 13:32, Niklas Cassel wrote:
> From: Damien Le Moal <damien.lemoal@opensource.wdc.com>
>
> Add the sysfs scsi device attribute cdl_enable to allow a user to turn
> enable or disable a device command duration limits feature. CDL is
> disabled by default. This feature must be explicitly enabled by a user by
> setting the cdl_enable attribute to 1.
>
> The new function scsi_cdl_enable() does not do anything beside setting
> the cdl_enable field of struct scsi_device in the case of a (real) scsi
> device (e.g. a SAS HDD). For ATA devices, the command duration limits
> feature needs to be enabled/disabled using the ATA feature sub-page of
> the control mode page. To do so, the scsi_cdl_enable() function checks
> if this mode page is supported using scsi_mode_sense(). If it is,
> scsi_mode_select() is used to enable and disable CDL.
>
> Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
> Co-developed-by: Niklas Cassel <niklas.cassel@wdc.com>
> Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
> ---
> Documentation/ABI/testing/sysfs-block-device | 13 ++++
> drivers/scsi/scsi.c | 62 ++++++++++++++++++++
> drivers/scsi/scsi_sysfs.c | 28 +++++++++
> include/scsi/scsi_device.h | 2 +
> 4 files changed, 105 insertions(+)
>
Reviewed-by: Hannes Reinecke <hare@suse.de>

Cheers,

Hannes
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