[PATCH 7/7] scsi: mpt3sas: Introduce sas_ncq_prio_supported sysfs sttribute
From: Damien Le Moal <hidden>
Date: 2021-08-02 09:03:10
Also in:
linux-block, linux-scsi
Subsystem:
lsilogic mpt fusion drivers (fc/sas/spi), scsi subsystem, the rest · Maintainers:
Sathya Prakash, Sreekanth Reddy, Suganath Prabu Subramani, Ranjan Kumar, "James E.J. Bottomley", "Martin K. Petersen", Linus Torvalds
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 <redacted> --- drivers/scsi/mpt3sas/mpt3sas_ctl.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+)
diff --git a/drivers/scsi/mpt3sas/mpt3sas_ctl.c b/drivers/scsi/mpt3sas/mpt3sas_ctl.c
index b66140e4c370..7bce8288fb4f 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_ctl.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_ctl.c@@ -3918,6 +3918,25 @@ 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 desciptor + * @buf: the buffer returned + * + * A sysfs 'read/write' 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 snprintf(buf, PAGE_SIZE, "%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 +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, };
--
2.31.1