Main updates since v1: - Now passes the same number of xfs_test with dax=always as without this series (some seem to fail on my setup normally). Thanks Dave for the suggestion as there were some deadlocks/crashes in v1 due to misshandling of write-protect faults and truncation which should now be fixed. - The pgmap field has been moved to the folio (thanks Matthew for the suggestion). - No longer remove the vmf_insert_pfn_pXd() functions and instead refactor them for use by DAX as Peter Xu suggested they will be needed in future and I see there are patches in linux-next that call them. FS DAX pages have always maintained their own page reference counts without following the normal rules for page reference counting. In particular pages are considered free when the refcount hits one rather than zero and refcounts are not added when mapping the page. Tracking this requires special PTE bits (PTE_DEVMAP) and a secondary mechanism for allowing GUP to hold references on the page (see get_dev_pagemap). However there doesn't seem to be any reason why FS DAX pages need their own reference counting scheme. By treating the refcounts on these pages the same way as normal pages we can remove a lot of special checks. In particular pXd_trans_huge() becomes the same as pXd_leaf(), although I haven't made that change here. It also frees up a valuable SW define PTE bit on architectures that have devmap PTE bits defined. It also almost certainly allows further clean-up of the devmap managed functions, but I have left that as a future improvment. I am not intimately familiar with the FS DAX code so would appreciate some careful review there. In particular I have not given any thought at all to CONFIG_FS_DAX_LIMITED. Signed-off-by: Alistair Popple <apopple@xxxxxxxxxx> --- Cc: dan.j.williams@xxxxxxxxx Cc: vishal.l.verma@xxxxxxxxx Cc: dave.jiang@xxxxxxxxx Cc: logang@xxxxxxxxxxxx Cc: bhelgaas@xxxxxxxxxx Cc: jack@xxxxxxx Cc: jgg@xxxxxxxx Cc: catalin.marinas@xxxxxxx Cc: will@xxxxxxxxxx Cc: mpe@xxxxxxxxxxxxxx Cc: npiggin@xxxxxxxxx Cc: dave.hansen@xxxxxxxxxxxxxxx Cc: ira.weiny@xxxxxxxxx Cc: willy@xxxxxxxxxxxxx Cc: djwong@xxxxxxxxxx Cc: tytso@xxxxxxx Cc: linmiaohe@xxxxxxxxxx Cc: david@xxxxxxxxxx Cc: peterx@xxxxxxxxxx Cc: linux-doc@xxxxxxxxxxxxxxx Cc: linux-kernel@xxxxxxxxxxxxxxx Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx Cc: linuxppc-dev@xxxxxxxxxxxxxxxx Cc: nvdimm@xxxxxxxxxxxxxxx Cc: linux-cxl@xxxxxxxxxxxxxxx Cc: linux-fsdevel@xxxxxxxxxxxxxxx Cc: linux-mm@xxxxxxxxx Cc: linux-ext4@xxxxxxxxxxxxxxx Cc: linux-xfs@xxxxxxxxxxxxxxx Cc: jhubbard@xxxxxxxxxx Cc: hch@xxxxxx Cc: david@xxxxxxxxxxxxx Alistair Popple (12): mm/gup.c: Remove redundant check for PCI P2PDMA page pci/p2pdma: Don't initialise page refcount to one fs/dax: Refactor wait for dax idle page mm: Allow compound zone device pages mm/memory: Add dax_insert_pfn huge_memory: Allow mappings of PUD sized pages huge_memory: Allow mappings of PMD sized pages gup: Don't allow FOLL_LONGTERM pinning of FS DAX pages mm: Update vm_normal_page() callers to accept FS DAX pages fs/dax: Properly refcount fs dax pages mm: Remove pXX_devmap callers mm: Remove devmap related functions and page table bits Documentation/mm/arch_pgtable_helpers.rst | 6 +- arch/arm64/Kconfig | 1 +- arch/arm64/include/asm/pgtable-prot.h | 1 +- arch/arm64/include/asm/pgtable.h | 24 +-- arch/powerpc/Kconfig | 1 +- arch/powerpc/include/asm/book3s/64/hash-4k.h | 6 +- arch/powerpc/include/asm/book3s/64/hash-64k.h | 7 +- arch/powerpc/include/asm/book3s/64/pgtable.h | 52 +---- arch/powerpc/include/asm/book3s/64/radix.h | 14 +- arch/powerpc/mm/book3s64/hash_pgtable.c | 3 +- arch/powerpc/mm/book3s64/pgtable.c | 8 +- arch/powerpc/mm/book3s64/radix_pgtable.c | 5 +- arch/powerpc/mm/pgtable.c | 2 +- arch/x86/Kconfig | 1 +- arch/x86/include/asm/pgtable.h | 50 +---- arch/x86/include/asm/pgtable_types.h | 5 +- arch/x86/mm/pat/memtype.c | 4 +- drivers/dax/device.c | 12 +- drivers/dax/super.c | 2 +- drivers/gpu/drm/nouveau/nouveau_dmem.c | 3 +- drivers/nvdimm/pmem.c | 4 +- drivers/pci/p2pdma.c | 12 +- fs/dax.c | 197 ++++++++--------- fs/ext4/inode.c | 5 +- fs/fuse/dax.c | 4 +- fs/fuse/virtio_fs.c | 3 +- fs/proc/task_mmu.c | 16 +- fs/userfaultfd.c | 2 +- fs/xfs/xfs_inode.c | 4 +- include/linux/dax.h | 12 +- include/linux/huge_mm.h | 15 +- include/linux/memremap.h | 17 +- include/linux/migrate.h | 4 +- include/linux/mm.h | 39 +--- include/linux/mm_types.h | 9 +- include/linux/mmzone.h | 8 +- include/linux/page-flags.h | 6 +- include/linux/pfn_t.h | 20 +-- include/linux/pgtable.h | 21 +-- include/linux/rmap.h | 15 +- lib/test_hmm.c | 3 +- mm/Kconfig | 4 +- mm/debug_vm_pgtable.c | 59 +----- mm/gup.c | 177 +--------------- mm/hmm.c | 12 +- mm/huge_memory.c | 221 +++++++++++-------- mm/internal.h | 2 +- mm/khugepaged.c | 2 +- mm/mapping_dirty_helpers.c | 4 +- mm/memcontrol-v1.c | 2 +- mm/memory-failure.c | 6 +- mm/memory.c | 126 +++++++---- mm/memremap.c | 53 ++--- mm/migrate_device.c | 9 +- mm/mlock.c | 2 +- mm/mm_init.c | 23 +- mm/mprotect.c | 2 +- mm/mremap.c | 5 +- mm/page_vma_mapped.c | 5 +- mm/pagewalk.c | 8 +- mm/pgtable-generic.c | 7 +- mm/rmap.c | 49 ++++- mm/swap.c | 2 +- mm/userfaultfd.c | 2 +- mm/vmscan.c | 5 +- 65 files changed, 591 insertions(+), 819 deletions(-) base-commit: 6f1833b8208c3b9e59eff10792667b6639365146 -- git-series 0.9.1
