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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /Documentation/ABI/testing/sysfs-block
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--Documentation/ABI/testing/sysfs-block318
-rw-r--r--Documentation/ABI/testing/sysfs-block-aoe45
-rw-r--r--Documentation/ABI/testing/sysfs-block-bcache156
-rw-r--r--Documentation/ABI/testing/sysfs-block-device60
-rw-r--r--Documentation/ABI/testing/sysfs-block-dm47
-rw-r--r--Documentation/ABI/testing/sysfs-block-loop50
-rw-r--r--Documentation/ABI/testing/sysfs-block-rnbd46
-rw-r--r--Documentation/ABI/testing/sysfs-block-rssd5
-rw-r--r--Documentation/ABI/testing/sysfs-block-zram139
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diff --git a/Documentation/ABI/testing/sysfs-block b/Documentation/ABI/testing/sysfs-block
new file mode 100644
index 000000000..e34cdeeeb
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@@ -0,0 +1,318 @@
+What: /sys/block/<disk>/stat
+Date: February 2008
+Contact: Jerome Marchand <jmarchan@redhat.com>
+Description:
+ The /sys/block/<disk>/stat files displays the I/O
+ statistics of disk <disk>. They contain 11 fields:
+
+ == ==============================================
+ 1 reads completed successfully
+ 2 reads merged
+ 3 sectors read
+ 4 time spent reading (ms)
+ 5 writes completed
+ 6 writes merged
+ 7 sectors written
+ 8 time spent writing (ms)
+ 9 I/Os currently in progress
+ 10 time spent doing I/Os (ms)
+ 11 weighted time spent doing I/Os (ms)
+ 12 discards completed
+ 13 discards merged
+ 14 sectors discarded
+ 15 time spent discarding (ms)
+ 16 flush requests completed
+ 17 time spent flushing (ms)
+ == ==============================================
+
+ For more details refer Documentation/admin-guide/iostats.rst
+
+
+What: /sys/block/<disk>/<part>/stat
+Date: February 2008
+Contact: Jerome Marchand <jmarchan@redhat.com>
+Description:
+ The /sys/block/<disk>/<part>/stat files display the
+ I/O statistics of partition <part>. The format is the
+ same as the above-written /sys/block/<disk>/stat
+ format.
+
+
+What: /sys/block/<disk>/integrity/format
+Date: June 2008
+Contact: Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+ Metadata format for integrity capable block device.
+ E.g. T10-DIF-TYPE1-CRC.
+
+
+What: /sys/block/<disk>/integrity/read_verify
+Date: June 2008
+Contact: Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+ Indicates whether the block layer should verify the
+ integrity of read requests serviced by devices that
+ support sending integrity metadata.
+
+
+What: /sys/block/<disk>/integrity/tag_size
+Date: June 2008
+Contact: Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+ Number of bytes of integrity tag space available per
+ 512 bytes of data.
+
+
+What: /sys/block/<disk>/integrity/device_is_integrity_capable
+Date: July 2014
+Contact: Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+ Indicates whether a storage device is capable of storing
+ integrity metadata. Set if the device is T10 PI-capable.
+
+What: /sys/block/<disk>/integrity/protection_interval_bytes
+Date: July 2015
+Contact: Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+ Describes the number of data bytes which are protected
+ by one integrity tuple. Typically the device's logical
+ block size.
+
+What: /sys/block/<disk>/integrity/write_generate
+Date: June 2008
+Contact: Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+ Indicates whether the block layer should automatically
+ generate checksums for write requests bound for
+ devices that support receiving integrity metadata.
+
+What: /sys/block/<disk>/alignment_offset
+Date: April 2009
+Contact: Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+ Storage devices may report a physical block size that is
+ bigger than the logical block size (for instance a drive
+ with 4KB physical sectors exposing 512-byte logical
+ blocks to the operating system). This parameter
+ indicates how many bytes the beginning of the device is
+ offset from the disk's natural alignment.
+
+What: /sys/block/<disk>/<partition>/alignment_offset
+Date: April 2009
+Contact: Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+ Storage devices may report a physical block size that is
+ bigger than the logical block size (for instance a drive
+ with 4KB physical sectors exposing 512-byte logical
+ blocks to the operating system). This parameter
+ indicates how many bytes the beginning of the partition
+ is offset from the disk's natural alignment.
+
+What: /sys/block/<disk>/queue/logical_block_size
+Date: May 2009
+Contact: Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+ This is the smallest unit the storage device can
+ address. It is typically 512 bytes.
+
+What: /sys/block/<disk>/queue/physical_block_size
+Date: May 2009
+Contact: Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+ This is the smallest unit a physical storage device can
+ write atomically. It is usually the same as the logical
+ block size but may be bigger. One example is SATA
+ drives with 4KB sectors that expose a 512-byte logical
+ block size to the operating system. For stacked block
+ devices the physical_block_size variable contains the
+ maximum physical_block_size of the component devices.
+
+What: /sys/block/<disk>/queue/minimum_io_size
+Date: April 2009
+Contact: Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+ Storage devices may report a granularity or preferred
+ minimum I/O size which is the smallest request the
+ device can perform without incurring a performance
+ penalty. For disk drives this is often the physical
+ block size. For RAID arrays it is often the stripe
+ chunk size. A properly aligned multiple of
+ minimum_io_size is the preferred request size for
+ workloads where a high number of I/O operations is
+ desired.
+
+What: /sys/block/<disk>/queue/optimal_io_size
+Date: April 2009
+Contact: Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+ Storage devices may report an optimal I/O size, which is
+ the device's preferred unit for sustained I/O. This is
+ rarely reported for disk drives. For RAID arrays it is
+ usually the stripe width or the internal track size. A
+ properly aligned multiple of optimal_io_size is the
+ preferred request size for workloads where sustained
+ throughput is desired. If no optimal I/O size is
+ reported this file contains 0.
+
+What: /sys/block/<disk>/queue/nomerges
+Date: January 2010
+Contact:
+Description:
+ Standard I/O elevator operations include attempts to
+ merge contiguous I/Os. For known random I/O loads these
+ attempts will always fail and result in extra cycles
+ being spent in the kernel. This allows one to turn off
+ this behavior on one of two ways: When set to 1, complex
+ merge checks are disabled, but the simple one-shot merges
+ with the previous I/O request are enabled. When set to 2,
+ all merge tries are disabled. The default value is 0 -
+ which enables all types of merge tries.
+
+What: /sys/block/<disk>/discard_alignment
+Date: May 2011
+Contact: Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+ Devices that support discard functionality may
+ internally allocate space in units that are bigger than
+ the exported logical block size. The discard_alignment
+ parameter indicates how many bytes the beginning of the
+ device is offset from the internal allocation unit's
+ natural alignment.
+
+What: /sys/block/<disk>/<partition>/discard_alignment
+Date: May 2011
+Contact: Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+ Devices that support discard functionality may
+ internally allocate space in units that are bigger than
+ the exported logical block size. The discard_alignment
+ parameter indicates how many bytes the beginning of the
+ partition is offset from the internal allocation unit's
+ natural alignment.
+
+What: /sys/block/<disk>/queue/discard_granularity
+Date: May 2011
+Contact: Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+ Devices that support discard functionality may
+ internally allocate space using units that are bigger
+ than the logical block size. The discard_granularity
+ parameter indicates the size of the internal allocation
+ unit in bytes if reported by the device. Otherwise the
+ discard_granularity will be set to match the device's
+ physical block size. A discard_granularity of 0 means
+ that the device does not support discard functionality.
+
+What: /sys/block/<disk>/queue/discard_max_bytes
+Date: May 2011
+Contact: Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+ Devices that support discard functionality may have
+ internal limits on the number of bytes that can be
+ trimmed or unmapped in a single operation. Some storage
+ protocols also have inherent limits on the number of
+ blocks that can be described in a single command. The
+ discard_max_bytes parameter is set by the device driver
+ to the maximum number of bytes that can be discarded in
+ a single operation. Discard requests issued to the
+ device must not exceed this limit. A discard_max_bytes
+ value of 0 means that the device does not support
+ discard functionality.
+
+What: /sys/block/<disk>/queue/discard_zeroes_data
+Date: May 2011
+Contact: Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+ Will always return 0. Don't rely on any specific behavior
+ for discards, and don't read this file.
+
+What: /sys/block/<disk>/queue/write_same_max_bytes
+Date: January 2012
+Contact: Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+ Some devices support a write same operation in which a
+ single data block can be written to a range of several
+ contiguous blocks on storage. This can be used to wipe
+ areas on disk or to initialize drives in a RAID
+ configuration. write_same_max_bytes indicates how many
+ bytes can be written in a single write same command. If
+ write_same_max_bytes is 0, write same is not supported
+ by the device.
+
+What: /sys/block/<disk>/queue/write_zeroes_max_bytes
+Date: November 2016
+Contact: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
+Description:
+ Devices that support write zeroes operation in which a
+ single request can be issued to zero out the range of
+ contiguous blocks on storage without having any payload
+ in the request. This can be used to optimize writing zeroes
+ to the devices. write_zeroes_max_bytes indicates how many
+ bytes can be written in a single write zeroes command. If
+ write_zeroes_max_bytes is 0, write zeroes is not supported
+ by the device.
+
+What: /sys/block/<disk>/queue/zoned
+Date: September 2016
+Contact: Damien Le Moal <damien.lemoal@wdc.com>
+Description:
+ zoned indicates if the device is a zoned block device
+ and the zone model of the device if it is indeed zoned.
+ The possible values indicated by zoned are "none" for
+ regular block devices and "host-aware" or "host-managed"
+ for zoned block devices. The characteristics of
+ host-aware and host-managed zoned block devices are
+ described in the ZBC (Zoned Block Commands) and ZAC
+ (Zoned Device ATA Command Set) standards. These standards
+ also define the "drive-managed" zone model. However,
+ since drive-managed zoned block devices do not support
+ zone commands, they will be treated as regular block
+ devices and zoned will report "none".
+
+What: /sys/block/<disk>/queue/nr_zones
+Date: November 2018
+Contact: Damien Le Moal <damien.lemoal@wdc.com>
+Description:
+ nr_zones indicates the total number of zones of a zoned block
+ device ("host-aware" or "host-managed" zone model). For regular
+ block devices, the value is always 0.
+
+What: /sys/block/<disk>/queue/max_active_zones
+Date: July 2020
+Contact: Niklas Cassel <niklas.cassel@wdc.com>
+Description:
+ For zoned block devices (zoned attribute indicating
+ "host-managed" or "host-aware"), the sum of zones belonging to
+ any of the zone states: EXPLICIT OPEN, IMPLICIT OPEN or CLOSED,
+ is limited by this value. If this value is 0, there is no limit.
+
+What: /sys/block/<disk>/queue/max_open_zones
+Date: July 2020
+Contact: Niklas Cassel <niklas.cassel@wdc.com>
+Description:
+ For zoned block devices (zoned attribute indicating
+ "host-managed" or "host-aware"), the sum of zones belonging to
+ any of the zone states: EXPLICIT OPEN or IMPLICIT OPEN,
+ is limited by this value. If this value is 0, there is no limit.
+
+What: /sys/block/<disk>/queue/chunk_sectors
+Date: September 2016
+Contact: Hannes Reinecke <hare@suse.com>
+Description:
+ chunk_sectors has different meaning depending on the type
+ of the disk. For a RAID device (dm-raid), chunk_sectors
+ indicates the size in 512B sectors of the RAID volume
+ stripe segment. For a zoned block device, either
+ host-aware or host-managed, chunk_sectors indicates the
+ size in 512B sectors of the zones of the device, with
+ the eventual exception of the last zone of the device
+ which may be smaller.
+
+What: /sys/block/<disk>/queue/io_timeout
+Date: November 2018
+Contact: Weiping Zhang <zhangweiping@didiglobal.com>
+Description:
+ io_timeout is the request timeout in milliseconds. If a request
+ does not complete in this time then the block driver timeout
+ handler is invoked. That timeout handler can decide to retry
+ the request, to fail it or to start a device recovery strategy.
diff --git a/Documentation/ABI/testing/sysfs-block-aoe b/Documentation/ABI/testing/sysfs-block-aoe
new file mode 100644
index 000000000..b5837765b
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-block-aoe
@@ -0,0 +1,45 @@
+What: /sys/block/etherd*/mac
+Date: Apr, 2005
+KernelVersion: v2.6.12
+Contact: Ed L. Cashin <ed.cashin@acm.org>
+Description:
+ (RO) The ethernet address of the remote Ata over Ethernet (AoE)
+ device.
+
+What: /sys/block/etherd*/netif
+Date: Apr, 2005
+KernelVersion: v2.6.12
+Contact: Ed L. Cashin <ed.cashin@acm.org>
+Description:
+ (RO) The names of the network interfaces on the localhost (comma
+ separated) through which we are communicating with the remote
+ AoE device.
+
+What: /sys/block/etherd*/state
+Date: Apr, 2005
+KernelVersion: v2.6.12
+Contact: Ed L. Cashin <ed.cashin@acm.org>
+Description:
+ (RO) Device status. The state attribute is "up" when the device
+ is ready for I/O and "down" if detected but unusable. The
+ "down,closewait" state shows that the device is still open and
+ cannot come up again until it has been closed. The "up,kickme"
+ state means that the driver wants to send more commands to the
+ target but found out there were already the max number of
+ commands waiting for a response. It will retry again after being
+ kicked by the periodic timer handler routine.
+
+What: /sys/block/etherd*/firmware-version
+Date: Apr, 2005
+KernelVersion: v2.6.12
+Contact: Ed L. Cashin <ed.cashin@acm.org>
+Description:
+ (RO) Version of the firmware in the target.
+
+What: /sys/block/etherd*/payload
+Date: Dec, 2012
+KernelVersion: v3.10
+Contact: Ed L. Cashin <ed.cashin@acm.org>
+Description:
+ (RO) The amount of user data transferred (in bytes) inside each AoE
+ command on the network, network headers excluded.
diff --git a/Documentation/ABI/testing/sysfs-block-bcache b/Documentation/ABI/testing/sysfs-block-bcache
new file mode 100644
index 000000000..9e4bbc5d5
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-block-bcache
@@ -0,0 +1,156 @@
+What: /sys/block/<disk>/bcache/unregister
+Date: November 2010
+Contact: Kent Overstreet <kent.overstreet@gmail.com>
+Description:
+ A write to this file causes the backing device or cache to be
+ unregistered. If a backing device had dirty data in the cache,
+ writeback mode is automatically disabled and all dirty data is
+ flushed before the device is unregistered. Caches unregister
+ all associated backing devices before unregistering themselves.
+
+What: /sys/block/<disk>/bcache/clear_stats
+Date: November 2010
+Contact: Kent Overstreet <kent.overstreet@gmail.com>
+Description:
+ Writing to this file resets all the statistics for the device.
+
+What: /sys/block/<disk>/bcache/cache
+Date: November 2010
+Contact: Kent Overstreet <kent.overstreet@gmail.com>
+Description:
+ For a backing device that has cache, a symlink to
+ the bcache/ dir of that cache.
+
+What: /sys/block/<disk>/bcache/cache_hits
+Date: November 2010
+Contact: Kent Overstreet <kent.overstreet@gmail.com>
+Description:
+ For backing devices: integer number of full cache hits,
+ counted per bio. A partial cache hit counts as a miss.
+
+What: /sys/block/<disk>/bcache/cache_misses
+Date: November 2010
+Contact: Kent Overstreet <kent.overstreet@gmail.com>
+Description:
+ For backing devices: integer number of cache misses.
+
+What: /sys/block/<disk>/bcache/cache_hit_ratio
+Date: November 2010
+Contact: Kent Overstreet <kent.overstreet@gmail.com>
+Description:
+ For backing devices: cache hits as a percentage.
+
+What: /sys/block/<disk>/bcache/sequential_cutoff
+Date: November 2010
+Contact: Kent Overstreet <kent.overstreet@gmail.com>
+Description:
+ For backing devices: Threshold past which sequential IO will
+ skip the cache. Read and written as bytes in human readable
+ units (i.e. echo 10M > sequntial_cutoff).
+
+What: /sys/block/<disk>/bcache/bypassed
+Date: November 2010
+Contact: Kent Overstreet <kent.overstreet@gmail.com>
+Description:
+ Sum of all reads and writes that have bypassed the cache (due
+ to the sequential cutoff). Expressed as bytes in human
+ readable units.
+
+What: /sys/block/<disk>/bcache/writeback
+Date: November 2010
+Contact: Kent Overstreet <kent.overstreet@gmail.com>
+Description:
+ For backing devices: When on, writeback caching is enabled and
+ writes will be buffered in the cache. When off, caching is in
+ writethrough mode; reads and writes will be added to the
+ cache but no write buffering will take place.
+
+What: /sys/block/<disk>/bcache/writeback_running
+Date: November 2010
+Contact: Kent Overstreet <kent.overstreet@gmail.com>
+Description:
+ For backing devices: when off, dirty data will not be written
+ from the cache to the backing device. The cache will still be
+ used to buffer writes until it is mostly full, at which point
+ writes transparently revert to writethrough mode. Intended only
+ for benchmarking/testing.
+
+What: /sys/block/<disk>/bcache/writeback_delay
+Date: November 2010
+Contact: Kent Overstreet <kent.overstreet@gmail.com>
+Description:
+ For backing devices: In writeback mode, when dirty data is
+ written to the cache and the cache held no dirty data for that
+ backing device, writeback from cache to backing device starts
+ after this delay, expressed as an integer number of seconds.
+
+What: /sys/block/<disk>/bcache/writeback_percent
+Date: November 2010
+Contact: Kent Overstreet <kent.overstreet@gmail.com>
+Description:
+ For backing devices: If nonzero, writeback from cache to
+ backing device only takes place when more than this percentage
+ of the cache is used, allowing more write coalescing to take
+ place and reducing total number of writes sent to the backing
+ device. Integer between 0 and 40.
+
+What: /sys/block/<disk>/bcache/synchronous
+Date: November 2010
+Contact: Kent Overstreet <kent.overstreet@gmail.com>
+Description:
+ For a cache, a boolean that allows synchronous mode to be
+ switched on and off. In synchronous mode all writes are ordered
+ such that the cache can reliably recover from unclean shutdown;
+ if disabled bcache will not generally wait for writes to
+ complete but if the cache is not shut down cleanly all data
+ will be discarded from the cache. Should not be turned off with
+ writeback caching enabled.
+
+What: /sys/block/<disk>/bcache/discard
+Date: November 2010
+Contact: Kent Overstreet <kent.overstreet@gmail.com>
+Description:
+ For a cache, a boolean allowing discard/TRIM to be turned off
+ or back on if the device supports it.
+
+What: /sys/block/<disk>/bcache/bucket_size
+Date: November 2010
+Contact: Kent Overstreet <kent.overstreet@gmail.com>
+Description:
+ For a cache, bucket size in human readable units, as set at
+ cache creation time; should match the erase block size of the
+ SSD for optimal performance.
+
+What: /sys/block/<disk>/bcache/nbuckets
+Date: November 2010
+Contact: Kent Overstreet <kent.overstreet@gmail.com>
+Description:
+ For a cache, the number of usable buckets.
+
+What: /sys/block/<disk>/bcache/tree_depth
+Date: November 2010
+Contact: Kent Overstreet <kent.overstreet@gmail.com>
+Description:
+ For a cache, height of the btree excluding leaf nodes (i.e. a
+ one node tree will have a depth of 0).
+
+What: /sys/block/<disk>/bcache/btree_cache_size
+Date: November 2010
+Contact: Kent Overstreet <kent.overstreet@gmail.com>
+Description:
+ Number of btree buckets/nodes that are currently cached in
+ memory; cache dynamically grows and shrinks in response to
+ memory pressure from the rest of the system.
+
+What: /sys/block/<disk>/bcache/written
+Date: November 2010
+Contact: Kent Overstreet <kent.overstreet@gmail.com>
+Description:
+ For a cache, total amount of data in human readable units
+ written to the cache, excluding all metadata.
+
+What: /sys/block/<disk>/bcache/btree_written
+Date: November 2010
+Contact: Kent Overstreet <kent.overstreet@gmail.com>
+Description:
+ For a cache, sum of all btree writes in human readable units.
diff --git a/Documentation/ABI/testing/sysfs-block-device b/Documentation/ABI/testing/sysfs-block-device
new file mode 100644
index 000000000..aa0fb500e
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-block-device
@@ -0,0 +1,60 @@
+What: /sys/block/*/device/sw_activity
+Date: Jun, 2008
+KernelVersion: v2.6.27
+Contact: linux-ide@vger.kernel.org
+Description:
+ (RW) Used by drivers which support software controlled activity
+ LEDs.
+
+ It has the following valid values:
+
+ == ========================================================
+ 0 OFF - the LED is not activated on activity
+ 1 BLINK_ON - the LED blinks on every 10ms when activity is
+ detected.
+ 2 BLINK_OFF - the LED is on when idle, and blinks off
+ every 10ms when activity is detected.
+ == ========================================================
+
+ Note that the user must turn sw_activity OFF it they wish to
+ control the activity LED via the em_message file.
+
+
+What: /sys/block/*/device/unload_heads
+Date: Sep, 2008
+KernelVersion: v2.6.28
+Contact: linux-ide@vger.kernel.org
+Description:
+ (RW) Hard disk shock protection
+
+ Writing an integer value to this file will take the heads of the
+ respective drive off the platter and block all I/O operations
+ for the specified number of milliseconds.
+
+ - If the device does not support the unload heads feature,
+ access is denied with -EOPNOTSUPP.
+ - The maximal value accepted for a timeout is 30000
+ milliseconds.
+ - A previously set timeout can be cancelled and disk can resume
+ normal operation immediately by specifying a timeout of 0.
+ - Some hard drives only comply with an earlier version of the
+ ATA standard, but support the unload feature nonetheless.
+ There is no safe way Linux can detect these devices, so this
+ is not enabled by default. If it is known that your device
+ does support the unload feature, then you can tell the kernel
+ to enable it by writing -1. It can be disabled again by
+ writing -2.
+ - Values below -2 are rejected with -EINVAL
+
+ For more information, see
+ Documentation/admin-guide/laptops/disk-shock-protection.rst
+
+
+What: /sys/block/*/device/ncq_prio_enable
+Date: Oct, 2016
+KernelVersion: v4.10
+Contact: linux-ide@vger.kernel.org
+Description:
+ (RW) Write to the file to turn on or off the SATA ncq (native
+ command queueing) support. By default this feature is turned
+ off.
diff --git a/Documentation/ABI/testing/sysfs-block-dm b/Documentation/ABI/testing/sysfs-block-dm
new file mode 100644
index 000000000..f9f2339b9
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-block-dm
@@ -0,0 +1,47 @@
+What: /sys/block/dm-<num>/dm/name
+Date: January 2009
+KernelVersion: 2.6.29
+Contact: dm-devel@redhat.com
+Description: Device-mapper device name.
+ Read-only string containing mapped device name.
+Users: util-linux, device-mapper udev rules
+
+What: /sys/block/dm-<num>/dm/uuid
+Date: January 2009
+KernelVersion: 2.6.29
+Contact: dm-devel@redhat.com
+Description: Device-mapper device UUID.
+ Read-only string containing DM-UUID or empty string
+ if DM-UUID is not set.
+Users: util-linux, device-mapper udev rules
+
+What: /sys/block/dm-<num>/dm/suspended
+Date: June 2009
+KernelVersion: 2.6.31
+Contact: dm-devel@redhat.com
+Description: Device-mapper device suspend state.
+ Contains the value 1 while the device is suspended.
+ Otherwise it contains 0. Read-only attribute.
+Users: util-linux, device-mapper udev rules
+
+What: /sys/block/dm-<num>/dm/rq_based_seq_io_merge_deadline
+Date: March 2015
+KernelVersion: 4.1
+Contact: dm-devel@redhat.com
+Description: Allow control over how long a request that is a
+ reasonable merge candidate can be queued on the request
+ queue. The resolution of this deadline is in
+ microseconds (ranging from 1 to 100000 usecs).
+ Setting this attribute to 0 (the default) will disable
+ request-based DM's merge heuristic and associated extra
+ accounting. This attribute is not applicable to
+ bio-based DM devices so it will only ever report 0 for
+ them.
+
+What: /sys/block/dm-<num>/dm/use_blk_mq
+Date: March 2015
+KernelVersion: 4.1
+Contact: dm-devel@redhat.com
+Description: Request-based Device-mapper blk-mq I/O path mode.
+ Contains the value 1 if the device is using blk-mq.
+ Otherwise it contains 0. Read-only attribute.
diff --git a/Documentation/ABI/testing/sysfs-block-loop b/Documentation/ABI/testing/sysfs-block-loop
new file mode 100644
index 000000000..627f4eb87
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-block-loop
@@ -0,0 +1,50 @@
+What: /sys/block/loopX/loop/autoclear
+Date: Aug, 2010
+KernelVersion: v2.6.37
+Contact: linux-block@vger.kernel.org
+Description:
+ (RO) Shows if the device is in autoclear mode or not ( "1" or
+ "0"). Autoclear (if set) indicates that the loopback device will
+ self-distruct after last close.
+
+What: /sys/block/loopX/loop/backing_file
+Date: Aug, 2010
+KernelVersion: v2.6.37
+Contact: linux-block@vger.kernel.org
+Description:
+ (RO) The path of the backing file that the loop device maps its
+ data blocks to.
+
+What: /sys/block/loopX/loop/offset
+Date: Aug, 2010
+KernelVersion: v2.6.37
+Contact: linux-block@vger.kernel.org
+Description:
+ (RO) Start offset (in bytes).
+
+What: /sys/block/loopX/loop/sizelimit
+Date: Aug, 2010
+KernelVersion: v2.6.37
+Contact: linux-block@vger.kernel.org
+Description:
+ (RO) The size (in bytes) that the block device maps, starting
+ from the offset.
+
+What: /sys/block/loopX/loop/partscan
+Date: Aug, 2011
+KernelVersion: v3.10
+Contact: linux-block@vger.kernel.org
+Description:
+ (RO) Shows if automatic partition scanning is enabled for the
+ device or not ("1" or "0"). This can be requested individually
+ per loop device during its setup by setting LO_FLAGS_PARTSCAN in
+ in the ioctl request. By default, no partition tables are
+ scanned.
+
+What: /sys/block/loopX/loop/dio
+Date: Aug, 2015
+KernelVersion: v4.10
+Contact: linux-block@vger.kernel.org
+Description:
+ (RO) Shows if direct IO is being used to access backing file or
+ not ("1 or "0").
diff --git a/Documentation/ABI/testing/sysfs-block-rnbd b/Documentation/ABI/testing/sysfs-block-rnbd
new file mode 100644
index 000000000..14a6fe942
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-block-rnbd
@@ -0,0 +1,46 @@
+What: /sys/block/rnbd<N>/rnbd/unmap_device
+Date: Feb 2020
+KernelVersion: 5.7
+Contact: Jack Wang <jinpu.wang@cloud.ionos.com> Danil Kipnis <danil.kipnis@cloud.ionos.com>
+Description: To unmap a volume, "normal" or "force" has to be written to:
+ /sys/block/rnbd<N>/rnbd/unmap_device
+
+ When "normal" is used, the operation will fail with EBUSY if any process
+ is using the device. When "force" is used, the device is also unmapped
+ when device is in use. All I/Os that are in progress will fail.
+
+ Example::
+
+ # echo "normal" > /sys/block/rnbd0/rnbd/unmap_device
+
+What: /sys/block/rnbd<N>/rnbd/state
+Date: Feb 2020
+KernelVersion: 5.7
+Contact: Jack Wang <jinpu.wang@cloud.ionos.com> Danil Kipnis <danil.kipnis@cloud.ionos.com>
+Description: The file contains the current state of the block device. The state file
+ returns "open" when the device is successfully mapped from the server
+ and accepting I/O requests. When the connection to the server gets
+ disconnected in case of an error (e.g. link failure), the state file
+ returns "closed" and all I/O requests submitted to it will fail with -EIO.
+
+What: /sys/block/rnbd<N>/rnbd/session
+Date: Feb 2020
+KernelVersion: 5.7
+Contact: Jack Wang <jinpu.wang@cloud.ionos.com> Danil Kipnis <danil.kipnis@cloud.ionos.com>
+Description: RNBD uses RTRS session to transport the data between client and
+ server. The entry "session" contains the name of the session, that
+ was used to establish the RTRS session. It's the same name that
+ was passed as server parameter to the map_device entry.
+
+What: /sys/block/rnbd<N>/rnbd/mapping_path
+Date: Feb 2020
+KernelVersion: 5.7
+Contact: Jack Wang <jinpu.wang@cloud.ionos.com> Danil Kipnis <danil.kipnis@cloud.ionos.com>
+Description: Contains the path that was passed as "device_path" to the map_device
+ operation.
+
+What: /sys/block/rnbd<N>/rnbd/access_mode
+Date: Feb 2020
+KernelVersion: 5.7
+Contact: Jack Wang <jinpu.wang@cloud.ionos.com> Danil Kipnis <danil.kipnis@cloud.ionos.com>
+Description: Contains the device access mode: ro, rw or migration.
diff --git a/Documentation/ABI/testing/sysfs-block-rssd b/Documentation/ABI/testing/sysfs-block-rssd
new file mode 100644
index 000000000..beef30c04
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-block-rssd
@@ -0,0 +1,5 @@
+What: /sys/block/rssd*/status
+Date: April 2012
+KernelVersion: 3.4
+Contact: Asai Thambi S P <asamymuthupa@micron.com>
+Description: This is a read-only file. Indicates the status of the device.
diff --git a/Documentation/ABI/testing/sysfs-block-zram b/Documentation/ABI/testing/sysfs-block-zram
new file mode 100644
index 000000000..14b2bf2e5
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-block-zram
@@ -0,0 +1,139 @@
+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.
+
+What: /sys/block/zram<id>/idle
+Date: November 2018
+Contact: Minchan Kim <minchan@kernel.org>
+Description:
+ idle file is write-only and mark zram slot as idle.
+ If system has mounted debugfs, user can see which slots
+ are idle via /sys/kernel/debug/zram/zram<id>/block_state
+
+What: /sys/block/zram<id>/writeback
+Date: November 2018
+Contact: Minchan Kim <minchan@kernel.org>
+Description:
+ The writeback file is write-only and trigger idle and/or
+ huge page writeback to backing device.
+
+What: /sys/block/zram<id>/bd_stat
+Date: November 2018
+Contact: Minchan Kim <minchan@kernel.org>
+Description:
+ The bd_stat file is read-only and represents backing device's
+ statistics (bd_count, bd_reads, bd_writes) in a format
+ similar to block layer statistics file format.
+
+What: /sys/block/zram<id>/writeback_limit_enable
+Date: November 2018
+Contact: Minchan Kim <minchan@kernel.org>
+Description:
+ The writeback_limit_enable file is read-write and specifies
+ eanbe of writeback_limit feature. "1" means eable the feature.
+ No limit "0" is the initial state.
+
+What: /sys/block/zram<id>/writeback_limit
+Date: November 2018
+Contact: Minchan Kim <minchan@kernel.org>
+Description:
+ The writeback_limit file is read-write and specifies the maximum
+ amount of writeback ZRAM can do. The limit could be changed
+ in run time.