diff options
| author |   Weiping Zhang <zhangweiping@didichuxing.com> | 2018-02-26 22:08:28 +0800 |
|---|---|---|
| committer |   Martin K. Petersen <martin.petersen@oracle.com> | 2018-03-01 21:26:54 -0500 |
| commit | 18d595bf9de99a0f092d8522da42df8b09ef5c2f (patch) | |
| tree | 0b23079c90a6f9ba5c3676ede8b8f3530912dafb /Documentation/scsi/sd-parameters.txt | |
| parent | scsi: atp870u: 64 bit bug in atp885_init() (diff) | |
| download | linux-dev-18d595bf9de99a0f092d8522da42df8b09ef5c2f.tar.xz linux-dev-18d595bf9de99a0f092d8522da42df8b09ef5c2f.zip | |
scsi: sd: Documentation: add sd-parameters.txt
Add a file for documenting SCSI sd module parameters and describe the
cache_type setting.
[mkp: tweaked text a bit]
Signed-off-by: Weiping Zhang <zhangweiping@didichuxing.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'Documentation/scsi/sd-parameters.txt')
| -rw-r--r-- | Documentation/scsi/sd-parameters.txt | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/Documentation/scsi/sd-parameters.txt b/Documentation/scsi/sd-parameters.txt new file mode 100644 index 000000000000..8e5af00d88e7 --- /dev/null +++ b/Documentation/scsi/sd-parameters.txt @@ -0,0 +1,22 @@ +Linux SCSI Disk Driver (sd) Parameters +====================================== + +cache_type (RW) +--------------- +Enable/disable drive write & read cache. + + cache_type string | WCE RCD | Write cache | Read cache +----------------------------+---------+-------------+------------ + write through | 0 0 | off | on + none | 0 1 | off | off + write back | 1 0 | on | on + write back, no read (daft) | 1 1 | on | off + +To set cache type to "write back" and save this setting to the drive: + + # echo "write back" > cache_type + +To modify the caching mode without making the change persistent, prepend +"temporary " to the cache type string. E.g.: + + # echo "temporary write back" > cache_type |