Export through sysfs as a scsi_disk attribute the zoned capabilities of
a disk ("zoned_cap" attribute file). This new attribute indicates in
human readable form (i.e. a string) the zoned block capabilities
implemented by the disk as found in the ZONED field of the disk block
device characteristics VPD page. The possible values are:
- "none": ZONED=00b (not reported), regular disk
- "host-aware": ZONED=01b, host-aware ZBC disk
- "drive-managed": ZONED=10b, drive-managed ZBC disk (regular disk
interface)
For completness, also add the following value which is detected using
the device type rather than the ZONED field:
- "host-managed": device type = 0x14 (TYPE_ZBC), host-managed ZBC disk
This new sysfs attribute is purely informational and complementary to
the "zoned" device request queue sysfs attribute as it allows
applications and user daemons (e.g. udev) to easily differentiate
regular disks from drive-managed SMR disks without the need for direct
access tools such as provided by sg3utils.
Signed-off-by: Damien Le Moal <damien.lemoal@xxxxxxx>
---
drivers/scsi/sd.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 8929e178c6f8..1bc2a061efa9 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -528,6 +528,21 @@ max_write_same_blocks_store(struct device *dev, struct device_attribute *attr,
}
static DEVICE_ATTR_RW(max_write_same_blocks);
+static ssize_t
+zoned_cap_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct scsi_disk *sdkp = to_scsi_disk(dev);
+
+ if (sdkp->device->type == TYPE_ZBC)
+ return sprintf(buf, "host-managed\n");
+ if (sdkp->zoned == 1)
+ return sprintf(buf, "host-aware\n");
+ if (sdkp->zoned == 2)
+ return sprintf(buf, "drive-managed\n");
+ return sprintf(buf, "none\n");
+}
+static DEVICE_ATTR_RO(zoned_cap);
+
static struct attribute *sd_disk_attrs[] = {
&dev_attr_cache_type.attr,
&dev_attr_FUA.attr,
@@ -541,6 +556,7 @@ static struct attribute *sd_disk_attrs[] = {
&dev_attr_zeroing_mode.attr,
&dev_attr_max_write_same_blocks.attr,
&dev_attr_max_medium_access_timeouts.attr,
+ &dev_attr_zoned_cap.attr,
NULL,
};
ATTRIBUTE_GROUPS(sd_disk);
--
2.25.4
