Changes since v1 [1]: 1/ Several simplifications from Christoph including dropping the __pfn_t dependency, and merging ZONE_DEVICE into the base arch_add_memory() implementation. 2/ Drop the deeper changes to the memory hotplug code that enabled allocating the backing 'struct page' array from pmem (struct vmem_altmap). This functionality is still needed when large capacity PMEM devices arrive. However, for now we can take this simple step to enable struct page mapping in RAM and enable it by default for small capacity CONFIG_X86_PMEM_LEGACY devices. 3/ A rework of the PMEM api to allow usage of the non-temporal memcpy_to_pmem() implementation even on platforms without pcommit instruction support. [1]: https://lists.01.org/pipermail/linux-nvdimm/2015-August/001809.html --- When we last left this debate [2] it was becoming clear that the 'page-less' approach left too many I/O scenarios off the table. The page-less enabling is still useful for avoiding the overhead of struct page where it is not needed, but in the end, page-backed persistent memory seems to be a requirement. We confirmed as much at the recently concluded Persistent Memory Microconference at Linux Plumbers. Whereas the initial RFC of this functionality enabled userspace to pick whether struct page is allocated from RAM or PMEM. This new version only enables RAM-backed for now. This is suitable for existing NVDIMM devices and a starting point to incrementally build "allocate struct page from PMEM" support. [2]: https://lists.01.org/pipermail/linux-nvdimm/2015-May/000748.html --- Christoph Hellwig (2): mm: move __phys_to_pfn and __pfn_to_phys to asm/generic/memory_model.h add devm_memremap_pages Dan Williams (7): dax: drop size parameter to ->direct_access() mm: ZONE_DEVICE for "device memory" x86, pmem: push fallback handling to arch code libnvdimm, pfn: 'struct page' provider infrastructure libnvdimm, pmem: 'struct page' for pmem libnvdimm, pmem: direct map legacy pmem by default devm_memremap_pages: protect against pmem device unbind arch/arm/include/asm/memory.h | 6 - arch/arm64/include/asm/memory.h | 6 - arch/ia64/mm/init.c | 4 arch/powerpc/mm/mem.c | 4 arch/powerpc/sysdev/axonram.c | 2 arch/s390/mm/init.c | 2 arch/sh/mm/init.c | 5 - arch/tile/mm/init.c | 2 arch/unicore32/include/asm/memory.h | 6 - arch/x86/include/asm/io.h | 2 arch/x86/include/asm/pmem.h | 41 ++++ arch/x86/mm/init_32.c | 4 arch/x86/mm/init_64.c | 4 drivers/acpi/nfit.c | 2 drivers/block/brd.c | 6 - drivers/nvdimm/Kconfig | 23 ++ drivers/nvdimm/Makefile | 2 drivers/nvdimm/btt.c | 6 - drivers/nvdimm/btt_devs.c | 172 +----------------- drivers/nvdimm/claim.c | 201 +++++++++++++++++++++ drivers/nvdimm/e820.c | 1 drivers/nvdimm/namespace_devs.c | 62 +++++- drivers/nvdimm/nd-core.h | 9 + drivers/nvdimm/nd.h | 59 ++++++ drivers/nvdimm/pfn.h | 35 ++++ drivers/nvdimm/pfn_devs.c | 337 +++++++++++++++++++++++++++++++++++ drivers/nvdimm/pmem.c | 220 +++++++++++++++++++++-- drivers/nvdimm/region.c | 2 drivers/nvdimm/region_devs.c | 20 ++ drivers/s390/block/dcssblk.c | 4 fs/block_dev.c | 2 include/asm-generic/memory_model.h | 6 + include/asm-generic/pmem.h | 72 +++++++ include/linux/blkdev.h | 2 include/linux/io.h | 57 ++++++ include/linux/libnvdimm.h | 4 include/linux/memory_hotplug.h | 5 - include/linux/mmzone.h | 23 ++ include/linux/pmem.h | 73 +------- kernel/memremap.c | 136 ++++++++++++++ mm/Kconfig | 17 ++ mm/memory_hotplug.c | 14 + mm/page_alloc.c | 3 tools/testing/nvdimm/Kbuild | 3 tools/testing/nvdimm/test/iomap.c | 13 + 45 files changed, 1369 insertions(+), 310 deletions(-) create mode 100644 drivers/nvdimm/claim.c create mode 100644 drivers/nvdimm/pfn.h create mode 100644 drivers/nvdimm/pfn_devs.c create mode 100644 include/asm-generic/pmem.h -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>