diff options
Diffstat (limited to 'Documentation/ABI/testing/sysfs-block')
-rw-r--r-- | Documentation/ABI/testing/sysfs-block | 42 |
1 files changed, 42 insertions, 0 deletions
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. |