Linux v5.4-rc3 - dax
# SPDX-License-Identifier: GPL-2.0-only
tristate "DAX: direct access to differentiated memory"
default m if NVDIMM_DAX
tristate "Device DAX: direct access mapping device"
depends on TRANSPARENT_HUGEPAGE
Support raw access to differentiated (persistence, bandwidth,
latency...) memory via an mmap(2) capable character
device. Platform firmware or a device driver may identify a
platform memory resource that is differentiated from the
baseline memory pool. Mappings of a /dev/daxX.Y device impose
restrictions that make the mapping behavior deterministic.
tristate "PMEM DAX: direct access to persistent memory"
depends on LIBNVDIMM && NVDIMM_DAX && DEV_DAX
Support raw access to persistent memory. Note that this
driver consumes memory ranges allocated and exported by the
Say M if unsure
tristate "KMEM DAX: volatile-use of persistent memory"
depends on DEV_DAX
depends on MEMORY_HOTPLUG # for add_memory() and friends
Support access to persistent memory as if it were RAM. This
allows easier use of persistent memory by unmodified
To use this feature, a DAX device must be unbound from the
device_dax driver (PMEM DAX) and bound to this kmem driver
on each boot.
Say N if unsure.
tristate "PMEM DAX: support the deprecated /sys/class/dax interface"
depends on m && DEV_DAX_PMEM=m
Older versions of the libdaxctl library expect to find all
device-dax instances under /sys/class/dax. If libdaxctl in
your distribution is older than v58 say M, otherwise say N.