From: Damien Le Moal damien.lemoal@wdc.com
Commit 4758fd91d5a07d46be1101d6d47b289ed5d904d0 upstream.
Similarly to AHCI, introduce the device sysfs attribute sas_ncq_prio_supported to advertise 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 prioity commands.
Link: https://lore.kernel.org/r/20210807041859.579409-11-damien.lemoal@wdc.com Reviewed-by: Hannes Reinecke hare@suse.de Signed-off-by: Damien Le Moal damien.lemoal@wdc.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Integrated-by: Siyu Zhang siyu.zhang@windriver.com --- 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 db95cda1fad4..770b241d7bb2 100644 --- a/drivers/scsi/mpt3sas/mpt3sas_ctl.c +++ b/drivers/scsi/mpt3sas/mpt3sas_ctl.c @@ -3919,6 +3919,24 @@ 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 @@ -3961,6 +3979,7 @@ 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, };