Changes since the initial RFC [1] * Split the generic detection of the attribute from any policy / mechanism that leverages the EFI_MEMORY_SP designation (Ard). * Various cleanups to the lib/memregion implementation (Willy) * Rebase on v5.2-rc2 * Several fixes resulting from testing with efi_fake_mem and the work-in-progress patches that add HMAT support to qemu. Details in patch3 and patch8. [1]: https://lore.kernel.org/lkml/155440490809.3190322.15060922240602775809.stgit@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/ --- The EFI 2.8 Specification [2] introduces the EFI_MEMORY_SP ("specific purpose") memory attribute. This attribute bit replaces the deprecated ACPI HMAT "reservation hint" that was introduced in ACPI 6.2 and removed in ACPI 6.3. Given the increasing diversity of memory types that might be advertised to the operating system, there is a need for platform firmware to hint which memory ranges are free for the OS to use as general purpose memory and which ranges are intended for application specific usage. For example, an application with prior knowledge of the platform may expect to be able to exclusively allocate a precious / limited pool of high bandwidth memory. Alternatively, for the general purpose case, the operating system may want to make the memory available on a best effort basis as a unique numa-node with performance properties by the new CONFIG_HMEM_REPORTING [3] facility. In support of optionally allowing either application-exclusive and core-kernel-mm managed access to differentiated memory, claim EFI_MEMORY_SP ranges for exposure as device-dax instances by default. Such instances can be directly owned / mapped by a platform-topology-aware application. Alternatively, with the new kmem facility [4], the administrator has the option to instead designate that those memory ranges be hot-added to the core-kernel-mm as a unique memory numa-node. In short, allow for the decision about what software agent manages specific-purpose memory to be made at runtime. The patches are based on the new HMAT+HMEM_REPORTING facilities merged for v5.2-rc1. The implementation is tested with qemu emulation of HMAT [5] plus the efi_fake_mem facility for applying the EFI_MEMORY_SP attribute. [2]: https://uefi.org/sites/default/files/resources/UEFI_Spec_2_8_final.pdf [3]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=e1cf33aafb84 [4]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c221c0b0308f [5]: http://patchwork.ozlabs.org/cover/1096737/ --- Dan Williams (8): acpi: Drop drivers/acpi/hmat/ directory acpi/hmat: Skip publishing target info for nodes with no online memory efi: Enumerate EFI_MEMORY_SP x86, efi: Reserve UEFI 2.8 Specific Purpose Memory for dax lib/memregion: Uplevel the pmem "region" ida to a global allocator device-dax: Add a driver for "hmem" devices acpi/hmat: Register HMAT at device_initcall level acpi/hmat: Register "specific purpose" memory as an "hmem" device arch/x86/Kconfig | 20 +++++ arch/x86/boot/compressed/eboot.c | 5 + arch/x86/boot/compressed/kaslr.c | 2 arch/x86/include/asm/e820/types.h | 9 ++ arch/x86/kernel/e820.c | 9 ++ arch/x86/kernel/setup.c | 1 arch/x86/platform/efi/efi.c | 37 ++++++++- drivers/acpi/Kconfig | 13 +++ drivers/acpi/Makefile | 2 drivers/acpi/hmat.c | 149 +++++++++++++++++++++++++++++++++---- drivers/acpi/hmat/Kconfig | 11 --- drivers/acpi/hmat/Makefile | 2 drivers/acpi/numa.c | 15 +++- drivers/dax/Kconfig | 27 +++++-- drivers/dax/Makefile | 2 drivers/dax/hmem.c | 58 ++++++++++++++ drivers/firmware/efi/efi.c | 5 + drivers/nvdimm/Kconfig | 1 drivers/nvdimm/core.c | 1 drivers/nvdimm/nd-core.h | 1 drivers/nvdimm/region_devs.c | 13 +-- include/linux/efi.h | 15 ++++ include/linux/ioport.h | 1 include/linux/memblock.h | 7 ++ include/linux/memregion.h | 11 +++ lib/Kconfig | 7 ++ lib/Makefile | 1 lib/memregion.c | 15 ++++ mm/memblock.c | 4 + 29 files changed, 387 insertions(+), 57 deletions(-) rename drivers/acpi/{hmat/hmat.c => hmat.c} (81%) delete mode 100644 drivers/acpi/hmat/Kconfig delete mode 100644 drivers/acpi/hmat/Makefile create mode 100644 drivers/dax/hmem.c create mode 100644 include/linux/memregion.h create mode 100644 lib/memregion.c
