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Diffstat (limited to 'Documentation/ABI/testing/sysfs-block')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-block | 27 |
1 files changed, 14 insertions, 13 deletions
diff --git a/Documentation/ABI/testing/sysfs-block b/Documentation/ABI/testing/sysfs-block index 2b5d56127fc..279da08f754 100644 --- a/Documentation/ABI/testing/sysfs-block +++ b/Documentation/ABI/testing/sysfs-block @@ -206,16 +206,17 @@ Description: when a discarded area is read the discard_zeroes_data parameter will be set to one. Otherwise it will be 0 and the result of reading a discarded area is undefined. -What: /sys/block/<disk>/alias -Date: Aug 2011 -Contact: Nao Nishijima <nao.nishijima.xt@hitachi.com> -Description: - A raw device name of a disk does not always point a same disk - each boot-up time. Therefore, users have to use persistent - device names, which udev creates when the kernel finds a disk, - instead of raw device name. However, kernel doesn't show those - persistent names on its messages (e.g. dmesg). - This file can store an alias of the disk and it would be - appeared in kernel messages if it is set. A disk can have an - alias which length is up to 255bytes. Users can use alphabets, - numbers, "-" and "_" in alias name. This file is writeonce. + +What: /sys/block/<disk>/queue/write_same_max_bytes +Date: January 2012 +Contact: Martin K. Petersen <martin.petersen@oracle.com> +Description: + Some devices support a write same operation in which a + single data block can be written to a range of several + contiguous blocks on storage. This can be used to wipe + areas on disk or to initialize drives in a RAID + configuration. write_same_max_bytes indicates how many + bytes can be written in a single write same command. If + write_same_max_bytes is 0, write same is not supported + by the device. + |