Changes since v1 [1]: - Combine this series with "Manual definition of Soft Reserved memory devices" [2] as the pre-requisites are required to test the device-dax facility, the device-dax changes are part of the justification for the numa-info reworks. - Provide a generic version of numa data retrieval based on memblock for arm64 rather than adding a new / empty phys_to_target_node() stub alongside memory_add_physaddr_to_nid(). (Will) - Fix several corner case allocation bugs and pass the unit test written by Joao. - Lift the restriction that a 'seed' device must be activated before a new seed can be created. This minor sanity check was to prevent userspace spamming devices, but it gets in the way of some of allocation scenarios like allocating a memory-range that is guaranteed to never be evicted due to memory-side-cache conflicts. (Iqbal) - Add debug prints for space allocation decisions (Joao) - Rebased on v5.8-rc2 which included resolving conflicts in the kmem driver and memremap_pages(). [1]: http://lore.kernel.org/r/158500767138.2088294.17131646259803932461.stgit@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx [2]: http://lore.kernel.org/r/158489354353.1457606.8327903161927980740.stgit@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/ --- The device-dax facility allows an address range to be directly mapped through a chardev, or optionally hotplugged to the core kernel page allocator as System-RAM. It is the mechanism for converting persistent memory (pmem) to be used as another volatile memory pool i.e. the current Memory Tiering hot topic on linux-mm. In the case of pmem the nvdimm-namespace-label mechanism can sub-divide it, but that labeling mechanism is not available / applicable to soft-reserved ("EFI specific purpose") memory [3]. This series provides a sysfs-mechanism for the daxctl utility to enable provisioning of volatile-soft-reserved memory ranges. The motivations for this facility are: 1/ Allow performance differentiated memory ranges to be split between kernel-managed and directly-accessed use cases. 2/ Allow physical memory to be provisioned along performance relevant address boundaries. For example, divide a memory-side cache [4] along cache-color boundaries. 3/ Parcel out soft-reserved memory to VMs using device-dax as a security / permissions boundary [5]. Specifically I have seen people (ab)using memmap=nn!ss (mark System-RAM as Persistent Memory) just to get the device-dax interface on custom address ranges. A follow-on for the VM use case is to teach device-dax to dynamically allocate 'struct page' at runtime to reduce the duplication of 'struct page' space in both the guest and the host kernel for the same physical pages. Given the intersections of arm64, x86, and core memremap_pages() changes I'd like to explore taking this through the libnvdimm tree, but that is step 2. Any concerns with the proposed infrastructure changes (memblock-numainfo and multi-range-memremap-pages)? [3]: http://lore.kernel.org/r/157309097008.1579826.12818463304589384434.stgit@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx [4]: http://lore.kernel.org/r/154899811738.3165233.12325692939590944259.stgit@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx [5]: http://lore.kernel.org/r/20200110190313.17144-1-joao.m.martins@xxxxxxxxxx --- Dan Williams (22): x86/numa: Cleanup configuration dependent command-line options x86/numa: Add 'nohmat' option efi/fake_mem: Arrange for a resource entry per efi_fake_mem instance ACPI: HMAT: Refactor hmat_register_target_device to hmem_register_device resource: Report parent to walk_iomem_res_desc() callback x86: Move NUMA_KEEP_MEMINFO and related definition to x86-internals numa: Introduce a generic memory_add_physaddr_to_nid() memblock: Introduce a generic phys_addr_to_target_node() arm64: Convert to generic memblock for numa-info ACPI: HMAT: Attach a device for each soft-reserved range device-dax: Drop the dax_region.pfn_flags attribute device-dax: Move instance creation parameters to 'struct dev_dax_data' device-dax: Make pgmap optional for instance creation device-dax: Kill dax_kmem_res device-dax: Add an allocation interface for device-dax instances device-dax: Introduce 'seed' devices drivers/base: Make device_find_child_by_name() compatible with sysfs inputs device-dax: Add resize support mm/memremap_pages: Convert to 'struct range' mm/memremap_pages: Support multiple ranges per invocation device-dax: Add dis-contiguous resource support device-dax: Introduce 'mapping' devices arch/arm64/Kconfig | 1 arch/arm64/mm/numa.c | 10 arch/powerpc/kvm/book3s_hv_uvmem.c | 14 arch/x86/Kconfig | 7 arch/x86/include/asm/numa.h | 8 arch/x86/kernel/e820.c | 16 + arch/x86/mm/numa.c | 12 arch/x86/mm/numa_emulation.c | 3 arch/x86/mm/numa_internal.h | 7 arch/x86/xen/enlighten_pv.c | 2 drivers/acpi/numa/hmat.c | 76 --- drivers/acpi/numa/srat.c | 9 drivers/base/core.c | 2 drivers/dax/Kconfig | 6 drivers/dax/Makefile | 3 drivers/dax/bus.c | 902 ++++++++++++++++++++++++++++++-- drivers/dax/bus.h | 28 + drivers/dax/dax-private.h | 39 + drivers/dax/device.c | 97 ++- drivers/dax/hmem/Makefile | 6 drivers/dax/hmem/device.c | 100 ++++ drivers/dax/hmem/hmem.c | 20 - drivers/dax/kmem.c | 199 ++++--- drivers/dax/pmem/compat.c | 2 drivers/dax/pmem/core.c | 22 + drivers/firmware/efi/x86_fake_mem.c | 12 drivers/gpu/drm/nouveau/nouveau_dmem.c | 4 drivers/nvdimm/badrange.c | 26 - drivers/nvdimm/claim.c | 13 drivers/nvdimm/nd.h | 3 drivers/nvdimm/pfn_devs.c | 13 drivers/nvdimm/pmem.c | 27 + drivers/nvdimm/region.c | 21 - drivers/pci/p2pdma.c | 12 include/acpi/acpi_numa.h | 14 include/linux/dax.h | 8 include/linux/memblock.h | 4 include/linux/memremap.h | 11 include/linux/mm.h | 13 include/linux/numa.h | 9 include/linux/range.h | 6 kernel/resource.c | 11 mm/Kconfig | 7 mm/memblock.c | 22 + mm/memremap.c | 300 ++++++----- mm/page_alloc.c | 82 +++ tools/testing/nvdimm/dax-dev.c | 22 + tools/testing/nvdimm/test/iomap.c | 2 48 files changed, 1705 insertions(+), 528 deletions(-) create mode 100644 drivers/dax/hmem/Makefile create mode 100644 drivers/dax/hmem/device.c rename drivers/dax/{hmem.c => hmem/hmem.c} (74%) base-commit: 48778464bb7d346b47157d21ffde2af6b2d39110
