Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 100 insertions, 0 deletions

diff --git a/Documentation/ABI/testing/sysfs-block-zram b/Documentation/ABI/testing/sysfs-block-zram
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+What:		/sys/block/zram<id>/disksize
+Date:		August 2010
+Contact:	Nitin Gupta <ngupta@vflare.org>
+Description:
+		The disksize file is read-write and specifies the disk size
+		which represents the limit on the *uncompressed* worth of data
+		that can be stored in this disk.
+		Unit: bytes
+
+What:		/sys/block/zram<id>/initstate
+Date:		August 2010
+Contact:	Nitin Gupta <ngupta@vflare.org>
+Description:
+		The initstate file is read-only and shows the initialization
+		state of the device.
+
+What:		/sys/block/zram<id>/reset
+Date:		August 2010
+Contact:	Nitin Gupta <ngupta@vflare.org>
+Description:
+		The reset file is write-only and allows resetting the
+		device. The reset operation frees all the memory associated
+		with this device.
+
+What:		/sys/block/zram<id>/max_comp_streams
+Date:		February 2014
+Contact:	Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
+Description:
+		The max_comp_streams file is read-write and specifies the
+		number of backend's zcomp_strm compression streams (number of
+		concurrent compress operations).
+
+What:		/sys/block/zram<id>/comp_algorithm
+Date:		February 2014
+Contact:	Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
+Description:
+		The comp_algorithm file is read-write and lets to show
+		available and selected compression algorithms, change
+		compression algorithm selection.
+
+What:		/sys/block/zram<id>/mem_used_max
+Date:		August 2014
+Contact:	Minchan Kim <minchan@kernel.org>
+Description:
+		The mem_used_max file is write-only and is used to reset
+		the counter of maximum memory zram have consumed to store
+		compressed data. For resetting the value, you should write
+		"0". Otherwise, you could see -EINVAL.
+		Unit: bytes
+
+What:		/sys/block/zram<id>/mem_limit
+Date:		August 2014
+Contact:	Minchan Kim <minchan@kernel.org>
+Description:
+		The mem_limit file is write-only and specifies the maximum
+		amount of memory ZRAM can use to store the compressed data.
+		The limit could be changed in run time and "0" means disable
+		the limit. No limit is the initial state.  Unit: bytes
+
+What:		/sys/block/zram<id>/compact
+Date:		August 2015
+Contact:	Minchan Kim <minchan@kernel.org>
+Description:
+		The compact file is write-only and trigger compaction for
+		allocator zrm uses. The allocator moves some objects so that
+		it could free fragment space.
+
+What:		/sys/block/zram<id>/io_stat
+Date:		August 2015
+Contact:	Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
+Description:
+		The io_stat file is read-only and accumulates device's I/O
+		statistics not accounted by block layer. For example,
+		failed_reads, failed_writes, etc. File format is similar to
+		block layer statistics file format.
+
+What:		/sys/block/zram<id>/mm_stat
+Date:		August 2015
+Contact:	Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
+Description:
+		The mm_stat file is read-only and represents device's mm
+		statistics (orig_data_size, compr_data_size, etc.) in a format
+		similar to block layer statistics file format.
+
+What:		/sys/block/zram<id>/debug_stat
+Date:		July 2016
+Contact:	Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
+Description:
+		The debug_stat file is read-only and represents various
+		device's debugging info useful for kernel developers. Its
+		format is not documented intentionally and may change
+		anytime without any notice.
+
+What:		/sys/block/zram<id>/backing_dev
+Date:		June 2017
+Contact:	Minchan Kim <minchan@kernel.org>
+Description:
+		The backing_dev file is read-write and set up backing
+		device for zram to write incompressible pages.
+		For using, user should enable CONFIG_ZRAM_WRITEBACK.