menuconfig DEV_DAX tristate "DAX: direct access to differentiated memory" default m if NVDIMM_DAX depends on TRANSPARENT_HUGEPAGE help 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. if DEV_DAX config DEV_DAX_PMEM tristate "PMEM DAX: direct access to persistent memory" depends on NVDIMM_DAX default DEV_DAX help Support raw access to persistent memory. Note that this driver consumes memory ranges allocated and exported by the libnvdimm sub-system. Say Y if unsure config NR_DEV_DAX int "Maximum number of Device-DAX instances" default 32768 range 256 2147483647 endif