zram: document failed_reads, failed_writes stats

Document `failed_reads' and `failed_writes' device attributes.
Remove info about `discard' - there is no such zram attr.

Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/Documentation/ABI/testing/sysfs-block-zram b/Documentation/ABI/testing/sysfs-block-zram
index 3f0b9ae..8aa0468 100644 (file)
--- a/Documentation/ABI/testing/sysfs-block-zram
+++ b/Documentation/ABI/testing/sysfs-block-zram
@@ -43,6 +43,21 @@ Description:
                The invalid_io file is read-only and specifies the number of
                non-page-size-aligned I/O requests issued to this device.
 
+What:          /sys/block/zram<id>/failed_reads
+Date:          February 2014
+Contact:       Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
+Description:
+               The failed_reads file is read-only and specifies the number of
+               failed reads happened on this device.
+
+
+What:          /sys/block/zram<id>/failed_writes
+Date:          February 2014
+Contact:       Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
+Description:
+               The failed_writes file is read-only and specifies the number of
+               failed writes happened on this device.
+
 What:          /sys/block/zram<id>/notify_free
 Date:          August 2010
 Contact:       Nitin Gupta <ngupta@vflare.org>
@@ -53,15 +68,6 @@ Description:
                is freed. This statistic is applicable only when this disk is
                being used as a swap disk.
 
-What:          /sys/block/zram<id>/discard
-Date:          August 2010
-Contact:       Nitin Gupta <ngupta@vflare.org>
-Description:
-               The discard file is read-only and specifies the number of
-               discard requests received by this device. These requests
-               provide information to block device regarding blocks which are
-               no longer used by filesystem.
-
 What:          /sys/block/zram<id>/zero_pages
 Date:          August 2010
 Contact:       Nitin Gupta <ngupta@vflare.org>

diff --git a/Documentation/blockdev/zram.txt b/Documentation/blockdev/zram.txt
index 393541b..b31ac5e 100644 (file)
--- a/Documentation/blockdev/zram.txt
+++ b/Documentation/blockdev/zram.txt
@@ -51,9 +51,10 @@ size of the disk when not in use so a huge zram is wasteful.
                disksize
                num_reads
                num_writes
+               failed_reads
+               failed_writes
                invalid_io
                notify_free
-               discard
                zero_pages
                orig_data_size
                compr_data_size