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-rw-r--r--Documentation/ABI/testing/sysfs-block42
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diff --git a/Documentation/ABI/testing/sysfs-block b/Documentation/ABI/testing/sysfs-block
index 71d184dbb70d..2da04ce6aeef 100644
--- a/Documentation/ABI/testing/sysfs-block
+++ b/Documentation/ABI/testing/sysfs-block
@@ -235,3 +235,45 @@ Description:
write_same_max_bytes is 0, write same is not supported
by the device.
+What: /sys/block/<disk>/queue/write_zeroes_max_bytes
+Date: November 2016
+Contact: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
+Description:
+ Devices that support write zeroes operation in which a
+ single request can be issued to zero out the range of
+ contiguous blocks on storage without having any payload
+ in the request. This can be used to optimize writing zeroes
+ to the devices. write_zeroes_max_bytes indicates how many
+ bytes can be written in a single write zeroes command. If
+ write_zeroes_max_bytes is 0, write zeroes is not supported
+ by the device.
+
+What: /sys/block/<disk>/queue/zoned
+Date: September 2016
+Contact: Damien Le Moal <damien.lemoal@hgst.com>
+Description:
+ zoned indicates if the device is a zoned block device
+ and the zone model of the device if it is indeed zoned.
+ The possible values indicated by zoned are "none" for
+ regular block devices and "host-aware" or "host-managed"
+ for zoned block devices. The characteristics of
+ host-aware and host-managed zoned block devices are
+ described in the ZBC (Zoned Block Commands) and ZAC
+ (Zoned Device ATA Command Set) standards. These standards
+ also define the "drive-managed" zone model. However,
+ since drive-managed zoned block devices do not support
+ zone commands, they will be treated as regular block
+ devices and zoned will report "none".
+
+What: /sys/block/<disk>/queue/chunk_sectors
+Date: September 2016
+Contact: Hannes Reinecke <hare@suse.com>
+Description:
+ chunk_sectors has different meaning depending on the type
+ of the disk. For a RAID device (dm-raid), chunk_sectors
+ indicates the size in 512B sectors of the RAID volume
+ stripe segment. For a zoned block device, either
+ host-aware or host-managed, chunk_sectors indicates the
+ size of 512B sectors of the zones of the device, with
+ the eventual exception of the last zone of the device
+ which may be smaller.