1 # SPDX-License-Identifier: GPL-2.0-only
3 tristate "NVDIMM (Non-Volatile Memory Device) Support"
4 depends on PHYS_ADDR_T_64BIT
9 Generic support for non-volatile memory devices including
10 ACPI-6-NFIT defined resources. On platforms that define an
11 NFIT, or otherwise can discover NVDIMM resources, a libnvdimm
12 bus is registered to advertise PMEM (persistent memory)
13 namespaces (/dev/pmemX). A PMEM namespace refers to a
14 memory resource that may span multiple DIMMs and support DAX
20 tristate "PMEM: Persistent memory block device support"
24 select ND_PFN if NVDIMM_PFN
26 Memory ranges for PMEM are described by either an NFIT
27 (NVDIMM Firmware Interface Table, see CONFIG_NFIT_ACPI), a
28 non-standard OEM-specific E820 memory type (type-12, see
29 CONFIG_X86_PMEM_LEGACY), or it is manually specified by the
30 'memmap=nn[KMG]!ss[KMG]' kernel command line (see
31 Documentation/admin-guide/kernel-parameters.rst). This driver converts
32 these persistent memory ranges into block devices that are
33 capable of DAX (direct-access) file system mappings. See
34 Documentation/driver-api/nvdimm/nvdimm.rst for more details.
36 Say Y if you want to use an NVDIMM
45 bool "BTT: Block Translation Table (atomic sector updates)"
46 default y if LIBNVDIMM
49 The Block Translation Table (BTT) provides atomic sector
50 update semantics for persistent memory devices, so that
51 applications that rely on sector writes not being torn (a
52 guarantee that typical disks provide) can continue to do so.
53 The BTT manifests itself as an alternate personality for an
54 NVDIMM namespace, i.e. a namespace can be in raw mode pmemX,
63 bool "PFN: Map persistent (device) memory"
65 depends on ZONE_DEVICE
68 Map persistent memory, i.e. advertise it to the memory
69 management sub-system. By default persistent memory does
70 not support direct I/O, RDMA, or any other usage that
71 requires a 'struct page' to mediate an I/O request. This
72 driver allocates and initializes the infrastructure needed
73 to support those use cases.
78 bool "NVDIMM DAX: Raw access to persistent memory"
82 Support raw device dax access to a persistent memory
83 namespace. For environments that want to hard partition
84 persistent memory, this capability provides a mechanism to
85 sub-divide a namespace into character devices that can only be
86 accessed via DAX (mmap(2)).
91 tristate "Device-tree support for persistent memory regions"
95 Allows regions of persistent memory to be described in the
102 depends on ENCRYPTED_KEYS
103 depends on (LIBNVDIMM=ENCRYPTED_KEYS) || LIBNVDIMM=m
109 KMSAN, and other memory debug facilities, increase the size of
110 'struct page' to contain extra metadata. This collides with
111 the NVDIMM capability to store a potentially
112 larger-than-"System RAM" size 'struct page' array in a
113 reservation of persistent memory rather than limited /
114 precious DRAM. However, that reservation needs to persist for
115 the life of the given NVDIMM namespace. If you are using KMSAN
116 to debug an issue unrelated to NVDIMMs or DAX then say N to this
117 option. Otherwise, say Y but understand that any namespaces
118 (with the page array stored pmem) created with this build of
119 the kernel will permanently reserve and strand excess
120 capacity compared to the CONFIG_KMSAN=n case.
124 config NVDIMM_TEST_BUILD
125 tristate "Build the unit test core"
127 depends on COMPILE_TEST && X86_64
128 default m if COMPILE_TEST
130 Build the core of the unit test infrastructure. The result of
131 this build is non-functional for unit test execution, but it
132 otherwise helps catch build errors induced by changes to the
133 core devm_memremap_pages() implementation and other
136 config NVDIMM_SECURITY_TEST
137 bool "Enable NVDIMM security unit tests"
138 depends on NVDIMM_KEYS
140 The NVDIMM and CXL subsystems support unit testing of their device
141 security state machines. The NVDIMM_SECURITY_TEST option disables CPU
142 cache maintenance operations around events like secure erase and
143 overwrite. Also, when enabled, the NVDIMM subsystem core helps the unit
144 test implement a mock state machine.