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+What:		/sys/bus/dax/devices/daxX.Y/align
+Date:		October, 2020
+KernelVersion:	v5.10
+Contact:	nvdimm@lists.linux.dev
+Description:
+		(RW) Provides a way to specify an alignment for a dax device.
+		Values allowed are constrained by the physical address ranges
+		that back the dax device, and also by arch requirements.
+
+What:		/sys/bus/dax/devices/daxX.Y/mapping
+Date:		October, 2020
+KernelVersion:	v5.10
+Contact:	nvdimm@lists.linux.dev
+Description:
+		(WO) Provides a way to allocate a mapping range under a dax
+		device. Specified in the format <start>-<end>.
+
+What:		/sys/bus/dax/devices/daxX.Y/mapping[0..N]/start
+What:		/sys/bus/dax/devices/daxX.Y/mapping[0..N]/end
+What:		/sys/bus/dax/devices/daxX.Y/mapping[0..N]/page_offset
+Date:		October, 2020
+KernelVersion:	v5.10
+Contact:	nvdimm@lists.linux.dev
+Description:
+		(RO) A dax device may have multiple constituent discontiguous
+		address ranges. These are represented by the different
+		'mappingX' subdirectories. The 'start' attribute indicates the
+		start physical address for the given range. The 'end' attribute
+		indicates the end physical address for the given range. The
+		'page_offset' attribute indicates the offset of the current
+		range in the dax device.
+
+What:		/sys/bus/dax/devices/daxX.Y/resource
+Date:		June, 2019
+KernelVersion:	v5.3
+Contact:	nvdimm@lists.linux.dev
+Description:
+		(RO) The resource attribute indicates the starting physical
+		address of a dax device. In case of a device with multiple
+		constituent ranges, it indicates the starting address of the
+		first range.
+
+What:		/sys/bus/dax/devices/daxX.Y/size
+Date:		October, 2020
+KernelVersion:	v5.10
+Contact:	nvdimm@lists.linux.dev
+Description:
+		(RW) The size attribute indicates the total size of a dax
+		device. For creating subdivided dax devices, or for resizing
+		an existing device, the new size can be written to this as
+		part of the reconfiguration process.
+
+What:		/sys/bus/dax/devices/daxX.Y/numa_node
+Date:		November, 2019
+KernelVersion:	v5.5
+Contact:	nvdimm@lists.linux.dev
+Description:
+		(RO) If NUMA is enabled and the platform has affinitized the
+		backing device for this dax device, emit the CPU node
+		affinity for this device.
+
+What:		/sys/bus/dax/devices/daxX.Y/target_node
+Date:		February, 2019
+KernelVersion:	v5.1
+Contact:	nvdimm@lists.linux.dev
+Description:
+		(RO) The target-node attribute is the Linux numa-node that a
+		device-dax instance may create when it is online. Prior to
+		being online the device's 'numa_node' property reflects the
+		closest online cpu node which is the typical expectation of a
+		device 'numa_node'. Once it is online it becomes its own
+		distinct numa node.
+
+What:		$(readlink -f /sys/bus/dax/devices/daxX.Y)/../dax_region/available_size
+Date:		October, 2020
+KernelVersion:	v5.10
+Contact:	nvdimm@lists.linux.dev
+Description:
+		(RO) The available_size attribute tracks available dax region
+		capacity. This only applies to volatile hmem devices, not pmem
+		devices, since pmem devices are defined by nvdimm namespace
+		boundaries.
+
+What:		$(readlink -f /sys/bus/dax/devices/daxX.Y)/../dax_region/size
+Date:		July, 2017
+KernelVersion:	v5.1
+Contact:	nvdimm@lists.linux.dev
+Description:
+		(RO) The size attribute indicates the size of a given dax region
+		in bytes.
+
+What:		$(readlink -f /sys/bus/dax/devices/daxX.Y)/../dax_region/align
+Date:		October, 2020
+KernelVersion:	v5.10
+Contact:	nvdimm@lists.linux.dev
+Description:
+		(RO) The align attribute indicates alignment of the dax region.
+		Changes on align may not always be valid, when say certain
+		mappings were created with 2M and then we switch to 1G. This
+		validates all ranges against the new value being attempted, post
+		resizing.
+
+What:		$(readlink -f /sys/bus/dax/devices/daxX.Y)/../dax_region/seed
+Date:		October, 2020
+KernelVersion:	v5.10
+Contact:	nvdimm@lists.linux.dev
+Description:
+		(RO) The seed device is a concept for dynamic dax regions to be
+		able to split the region amongst multiple sub-instances.  The
+		seed device, similar to libnvdimm seed devices, is a device
+		that starts with zero capacity allocated and unbound to a
+		driver.
+
+What:		$(readlink -f /sys/bus/dax/devices/daxX.Y)/../dax_region/create
+Date:		October, 2020
+KernelVersion:	v5.10
+Contact:	nvdimm@lists.linux.dev
+Description:
+		(RW) The create interface to the dax region provides a way to
+		create a new unconfigured dax device under the given region, which
+		can then be configured (with a size etc.) and then probed.
+
+What:		$(readlink -f /sys/bus/dax/devices/daxX.Y)/../dax_region/delete
+Date:		October, 2020
+KernelVersion:	v5.10
+Contact:	nvdimm@lists.linux.dev
+Description:
+		(WO) The delete interface for a dax region provides for deletion
+		of any 0-sized and idle dax devices.
+
+What:		$(readlink -f /sys/bus/dax/devices/daxX.Y)/../dax_region/id
+Date:		July, 2017
+KernelVersion:	v5.1
+Contact:	nvdimm@lists.linux.dev
+Description:
+		(RO) The id attribute indicates the region id of a dax region.
