Cliff note: HMM offers 2 things (each standing on its own). First it allows to use device memory transparently inside any process without any modifications to process program code. Second it allows to mirror process address space on a device. Change since v15: - drop safety net patch - s/devm_memremap_pages_remove/devm_memunmap_pages Work is under way to use this feature inside nouveau (the upstream open source driver for NVidia GPU) either in 4.11 or 4.12 timeframe. But this patchset have been otherwise tested with the close source driver for NVidia GPU and thus we are confident it works and allow to use the hardware for seamless interaction between CPU and GPU in common address space of a process. I also discussed the features with other company and i am confident it can be use on other, yet, unrelease hardware. So hope this time it can be consider for 4.11 or i would like to know any reasons to not accept this patchset. Know issues: Device memory pick some random unuse physical address range. Latter memory hotplug might fails because of this. Intention is to fix this in latter patchset to use physical address above the platform limit thus making sure that no real memory can be hotplug at conflicting address. Patchset overview: Patchset is divided into 3 features that can each be use independently from one another. First is changes to ZONE_DEVICE so we can have struct page for device un-addressable memory (patch 2-6). Second is process address space mirroring (patch 8 to 10), this allow to snapshot CPU page table and to keep the device page table synchronize with the CPU one. Last is a new page migration helper which allow migration for range of virtual address using hardware copy engine (patch 11-14). Other patches just introduce common definitions or add safety net to catch wrong use of some of the features. Future plan: In this patchset i restricted myself to set of core features what is missing: - force read only on CPU for memory duplication and GPU atomic - changes to mmu_notifier for optimization purposes - migration of file back page to device memory I plan to submit a couple more patchset to implement those features once core HMM is upstream. Git tree: https://cgit.freedesktop.org/~glisse/linux/log/?h=hmm-v16 Previous patchset posting : v1 http://lwn.net/Articles/597289/ v2 https://lkml.org/lkml/2014/6/12/559 v3 https://lkml.org/lkml/2014/6/13/633 v4 https://lkml.org/lkml/2014/8/29/423 v5 https://lkml.org/lkml/2014/11/3/759 v6 http://lwn.net/Articles/619737/ v7 http://lwn.net/Articles/627316/ v8 https://lwn.net/Articles/645515/ v9 https://lwn.net/Articles/651553/ v10 https://lwn.net/Articles/654430/ v11 http://www.gossamer-threads.com/lists/linux/kernel/2286424 v12 http://www.kernelhub.org/?msg=972982&p=2 v13 https://lwn.net/Articles/706856/ v14 https://lkml.org/lkml/2016/12/8/344 v15 http://www.mail-archive.com/linux-kernel@xxxxxxxxxxxxxxx/msg1304107.html Jérôme Glisse (15): mm/memory/hotplug: convert device bool to int to allow for more flags v2 mm/ZONE_DEVICE/devmem_pages_remove: allow early removal of device memory v2 mm/ZONE_DEVICE/free-page: callback when page is freed mm/ZONE_DEVICE/unaddressable: add support for un-addressable device memory v2 mm/ZONE_DEVICE/x86: add support for un-addressable device memory mm/hmm: heterogeneous memory management (HMM for short) mm/hmm/mirror: mirror process address space on device with HMM helpers mm/hmm/mirror: helper to snapshot CPU page table mm/hmm/mirror: device page fault handler mm/hmm/migrate: support un-addressable ZONE_DEVICE page in migration mm/hmm/migrate: add new boolean copy flag to migratepage() callback mm/hmm/migrate: new memory migration helper for use with device memory v2 mm/hmm/migrate: optimize page map once in vma being migrated mm/hmm/devmem: device driver helper to hotplug ZONE_DEVICE memory v2 mm/hmm/devmem: dummy HMM device as an helper for ZONE_DEVICE memory MAINTAINERS | 7 + arch/ia64/mm/init.c | 23 +- arch/powerpc/mm/mem.c | 22 +- arch/s390/mm/init.c | 10 +- arch/sh/mm/init.c | 22 +- arch/tile/mm/init.c | 10 +- arch/x86/mm/init_32.c | 23 +- arch/x86/mm/init_64.c | 41 +- drivers/dax/pmem.c | 3 +- drivers/nvdimm/pmem.c | 7 +- drivers/staging/lustre/lustre/llite/rw26.c | 8 +- fs/aio.c | 7 +- fs/btrfs/disk-io.c | 11 +- fs/hugetlbfs/inode.c | 9 +- fs/nfs/internal.h | 5 +- fs/nfs/write.c | 9 +- fs/proc/task_mmu.c | 10 +- fs/ubifs/file.c | 8 +- include/linux/balloon_compaction.h | 3 +- include/linux/fs.h | 13 +- include/linux/hmm.h | 525 ++++++++++++++ include/linux/ioport.h | 1 + include/linux/memory_hotplug.h | 31 +- include/linux/memremap.h | 59 +- include/linux/migrate.h | 7 +- include/linux/mm_types.h | 5 + include/linux/swap.h | 18 +- include/linux/swapops.h | 67 ++ kernel/fork.c | 2 + kernel/memremap.c | 69 +- mm/Kconfig | 51 ++ mm/Makefile | 1 + mm/balloon_compaction.c | 2 +- mm/hmm.c | 1085 ++++++++++++++++++++++++++++ mm/memory.c | 64 +- mm/memory_hotplug.c | 14 +- mm/migrate.c | 687 +++++++++++++++++- mm/mprotect.c | 12 + mm/rmap.c | 47 ++ mm/zsmalloc.c | 12 +- tools/testing/nvdimm/test/iomap.c | 3 +- 41 files changed, 2926 insertions(+), 87 deletions(-) create mode 100644 include/linux/hmm.h create mode 100644 mm/hmm.c -- 2.4.3 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. 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