diff options
author | Damien Le Moal <dlemoal@kernel.org> | 2023-05-11 04:13:42 +0300 |
---|---|---|
committer | Martin K. Petersen <martin.petersen@oracle.com> | 2023-05-23 00:05:19 +0300 |
commit | 1b22cfb14142aba7742d307c4f8d7006f919308c (patch) | |
tree | 27f10d331c3e090a7e9903cd7c16663eaed9d4c7 /drivers | |
parent | 624885209f31eb9985bf51abe204ecbffe2fdeea (diff) | |
download | linux-1b22cfb14142aba7742d307c4f8d7006f919308c.tar.xz |
scsi: core: Allow enabling and disabling command duration limits
Add the sysfs scsi_device attribute cdl_enable to allow a user to 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 <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Co-developed-by: Niklas Cassel <niklas.cassel@wdc.com>
Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Link: https://lore.kernel.org/r/20230511011356.227789-10-nks@flawful.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/scsi/scsi.c | 62 | ||||
-rw-r--r-- | drivers/scsi/scsi_sysfs.c | 28 |
2 files changed, 90 insertions, 0 deletions
diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c index c03814ce23ca..c4bf99a842f3 100644 --- a/drivers/scsi/scsi.c +++ b/drivers/scsi/scsi.c @@ -652,6 +652,68 @@ void scsi_cdl_check(struct scsi_device *sdev) } /** + * scsi_cdl_enable - Enable or disable a SCSI device supports for Command + * Duration Limits + * @sdev: The target device + * @enable: the target state + */ +int scsi_cdl_enable(struct scsi_device *sdev, bool enable) +{ + struct scsi_mode_data data; + struct scsi_sense_hdr sshdr; + struct scsi_vpd *vpd; + bool is_ata = false; + char buf[64]; + int ret; + + if (!sdev->cdl_supported) + return -EOPNOTSUPP; + + rcu_read_lock(); + vpd = rcu_dereference(sdev->vpd_pg89); + if (vpd) + is_ata = true; + rcu_read_unlock(); + + /* + * For ATA devices, CDL needs to be enabled with a SET FEATURES command. + */ + if (is_ata) { + char *buf_data; + int len; + + ret = scsi_mode_sense(sdev, 0x08, 0x0a, 0xf2, buf, sizeof(buf), + 5 * HZ, 3, &data, NULL); + if (ret) + return -EINVAL; + + /* Enable CDL using the ATA feature page */ + len = min_t(size_t, sizeof(buf), + data.length - data.header_length - + data.block_descriptor_length); + buf_data = buf + data.header_length + + data.block_descriptor_length; + if (enable) + buf_data[4] = 0x02; + else + buf_data[4] = 0; + + ret = scsi_mode_select(sdev, 1, 0, buf_data, len, 5 * HZ, 3, + &data, &sshdr); + if (ret) { + if (scsi_sense_valid(&sshdr)) + scsi_print_sense_hdr(sdev, + dev_name(&sdev->sdev_gendev), &sshdr); + return ret; + } + } + + sdev->cdl_enable = enable; + + return 0; +} + +/** * scsi_device_get - get an additional reference to a scsi_device * @sdev: device to get a reference to * diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c index 98fcbbf1c1e3..60317676e45f 100644 --- a/drivers/scsi/scsi_sysfs.c +++ b/drivers/scsi/scsi_sysfs.c @@ -1222,6 +1222,33 @@ static DEVICE_ATTR(queue_ramp_up_period, S_IRUGO | S_IWUSR, sdev_show_queue_ramp_up_period, sdev_store_queue_ramp_up_period); +static ssize_t sdev_show_cdl_enable(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct scsi_device *sdev = to_scsi_device(dev); + + return sysfs_emit(buf, "%d\n", (int)sdev->cdl_enable); +} + +static ssize_t sdev_store_cdl_enable(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + int ret; + bool v; + + if (kstrtobool(buf, &v)) + return -EINVAL; + + ret = scsi_cdl_enable(to_scsi_device(dev), v); + if (ret) + return ret; + + return count; +} +static DEVICE_ATTR(cdl_enable, S_IRUGO | S_IWUSR, + sdev_show_cdl_enable, sdev_store_cdl_enable); + static umode_t scsi_sdev_attr_is_visible(struct kobject *kobj, struct attribute *attr, int i) { @@ -1302,6 +1329,7 @@ static struct attribute *scsi_sdev_attrs[] = { #endif &dev_attr_queue_ramp_up_period.attr, &dev_attr_cdl_supported.attr, + &dev_attr_cdl_enable.attr, REF_EVT(media_change), REF_EVT(inquiry_change_reported), REF_EVT(capacity_change_reported), |