On 8/6/21 9:42 AM, Damien Le Moal wrote:
> Similarly to AHCI, introduce the device sysfs attribute
> sas_ncq_prio_supported to advertize if a SATA device supports the NCQ
> priority feature. Without this new attribute, the user can only
> discover if a SATA device supports NCQ priority by trying to enable
> the feature use with the sas_ncq_prio_enable sysfs device attribute,
> which fails when the device does not support high priroity commands.
>
> Signed-off-by: Damien Le Moal <damien.lemoal@xxxxxxx>
> ---
> drivers/scsi/mpt3sas/mpt3sas_ctl.c | 19 +++++++++++++++++++
> 1 file changed, 19 insertions(+)
>
> diff --git a/drivers/scsi/mpt3sas/mpt3sas_ctl.c b/drivers/scsi/mpt3sas/mpt3sas_ctl.c
> index b66140e4c370..f83d4d32d459 100644
> --- a/drivers/scsi/mpt3sas/mpt3sas_ctl.c
> +++ b/drivers/scsi/mpt3sas/mpt3sas_ctl.c
> @@ -3918,6 +3918,24 @@ sas_device_handle_show(struct device *dev, struct device_attribute *attr,
> }
> static DEVICE_ATTR_RO(sas_device_handle);
>
> +/**
> + * sas_ncq_prio_supported_show - Indicate if device supports NCQ priority
> + * @dev: pointer to embedded device
> + * @attr: sas_ncq_prio_supported attribute descriptor
> + * @buf: the buffer returned
> + *
> + * A sysfs 'read-only' sdev attribute, only works with SATA
> + */
> +static ssize_t
> +sas_ncq_prio_supported_show(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct scsi_device *sdev = to_scsi_device(dev);
> +
> + return sysfs_emit(buf, "%d\n", scsih_ncq_prio_supp(sdev));
> +}
> +static DEVICE_ATTR_RO(sas_ncq_prio_supported);
> +
> /**
> * sas_ncq_prio_enable_show - send prioritized io commands to device
> * @dev: pointer to embedded device
> @@ -3960,6 +3978,7 @@ static DEVICE_ATTR_RW(sas_ncq_prio_enable);
> struct device_attribute *mpt3sas_dev_attrs[] = {
> &dev_attr_sas_address,
> &dev_attr_sas_device_handle,
> + &dev_attr_sas_ncq_prio_supported,
> &dev_attr_sas_ncq_prio_enable,
> NULL,
> };
>
One wonders where the relationship to the previous patches are, but hey:
Reviewed-by: Hannes Reinecke <hare@xxxxxxx>
Cheers,
Hannes
--
Dr. Hannes Reinecke Kernel Storage Architect
hare@xxxxxxx +49 911 74053 688
SUSE Software Solutions Germany GmbH, Maxfeldstr. 5, 90409 Nürnberg
HRB 36809 (AG Nürnberg), GF: Felix Imendörffer
