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authorJoe Lawrence <joe.lawrence@redhat.com>2016-08-09 14:01:30 -0400
committerJens Axboe <axboe@fb.com>2016-08-11 09:37:23 -0600
commit005411ea7ee776a56b1e0120a31c65efdee5cab1 (patch)
tree8e9a7f2da028926e27ee8544cd7b1e7d66bf0c40 /Documentation/block
parentc21377f8366c95440d533edbe47d070f662c62ef (diff)
downloadlinux-005411ea7ee776a56b1e0120a31c65efdee5cab1.tar.bz2
doc: update block/queue-sysfs.txt entries
Add descriptions for dax, io_poll, and write_same_max_bytes files. Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'Documentation/block')
-rw-r--r--Documentation/block/queue-sysfs.txt18
1 files changed, 18 insertions, 0 deletions
diff --git a/Documentation/block/queue-sysfs.txt b/Documentation/block/queue-sysfs.txt
index d515d58962b9..2a3904030dea 100644
--- a/Documentation/block/queue-sysfs.txt
+++ b/Documentation/block/queue-sysfs.txt
@@ -14,6 +14,12 @@ add_random (RW)
This file allows to turn off the disk entropy contribution. Default
value of this file is '1'(on).
+dax (RO)
+--------
+This file indicates whether the device supports Direct Access (DAX),
+used by CPU-addressable storage to bypass the pagecache. It shows '1'
+if true, '0' if not.
+
discard_granularity (RO)
-----------------------
This shows the size of internal allocation of the device in bytes, if
@@ -46,6 +52,12 @@ hw_sector_size (RO)
-------------------
This is the hardware sector size of the device, in bytes.
+io_poll (RW)
+------------
+When read, this file shows the total number of block IO polls and how
+many returned success. Writing '0' to this file will disable polling
+for this device. Writing any non-zero value will enable this feature.
+
iostats (RW)
-------------
This file is used to control (on/off) the iostats accounting of the
@@ -151,5 +163,11 @@ device state. This means that it might not be safe to toggle the
setting from "write back" to "write through", since that will also
eliminate cache flushes issued by the kernel.
+write_same_max_bytes (RO)
+-------------------------
+This is the number of bytes the device can write in a single write-same
+command. A value of '0' means write-same is not supported by this
+device.
+
Jens Axboe <jens.axboe@oracle.com>, February 2009