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| author | Chaitanya Kulkarni <chaitanya.kulkarni@hgst.com> | 2016-11-30 23:28:59 +0300 |
|---|---|---|
| committer | Jens Axboe <axboe@fb.com> | 2016-12-01 17:58:40 +0300 |
| commit | a6f0788ec2881ac14e97ff7fa6a78a807f87b5ba (patch) | |
| tree | 493bf4be078a224b84c405220965e7a6c00a505c /Documentation/ABI/testing/sysfs-block | |
| parent | e73c23ff736e1ea371dfa419d7bf8e77ee53044a (diff) | |
| download | linux-a6f0788ec2881ac14e97ff7fa6a78a807f87b5ba.tar.xz | |
block: add support for REQ_OP_WRITE_ZEROES
This adds a new block layer operation to zero out a range of
LBAs. This allows to implement zeroing for devices that don't use
either discard with a predictable zero pattern or WRITE SAME of zeroes.
The prominent example of that is NVMe with the Write Zeroes command,
but in the future, this should also help with improving the way
zeroing discards work. For this operation, suitable entry is exported in
sysfs which indicate the number of maximum bytes allowed in one
write zeroes operation by the device.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@hgst.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'Documentation/ABI/testing/sysfs-block')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-block | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-block b/Documentation/ABI/testing/sysfs-block index ee2d5cd26bfe..2da04ce6aeef 100644 --- a/Documentation/ABI/testing/sysfs-block +++ b/Documentation/ABI/testing/sysfs-block @@ -235,6 +235,19 @@ 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> |