summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--Documentation/scsi/sd-parameters.txt22
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