protection_map[] is an array based construct that translates given vm_flags combination. This array contains page protection map, which is populated by the platform via [__S000 .. __S111] and [__P000 .. __P111] exported macros. Primary usage for protection_map[] is for vm_get_page_prot(), which is used to determine page protection value for a given vm_flags. vm_get_page_prot() implementation, could again call platform overrides arch_vm_get_page_prot() and arch_filter_pgprot(). Some platforms override protection_map[] that was originally built with __SXXX/__PXXX with different runtime values. Currently there are multiple layers of abstraction i.e __SXXX/__PXXX macros , protection_map[], arch_vm_get_page_prot() and arch_filter_pgprot() built between the platform and generic MM, finally defining vm_get_page_prot(). Hence this series proposes to drop all these abstraction levels and instead just move the responsibility of defining vm_get_page_prot() to the platform itself making it clean and simple. This first introduces ARCH_HAS_VM_GET_PAGE_PROT which enables the platforms to define custom vm_get_page_prot(). This starts converting platforms that either change protection_map[] or define the overrides arch_filter_pgprot() or arch_vm_get_page_prot() which enables for those constructs to be dropped off completely. This series then converts remaining platforms which enables for __SXXX/__PXXX constructs to be dropped off completely. Finally it drops the generic vm_get_page_prot() and then ARCH_HAS_VM_GET_PAGE_PROT as every platform now defines their own vm_get_page_prot(). The last patch demonstrates how vm_flags combination indices can be defined as macros and be replaces across all platforms (if required, not done yet). The series has been inspired from an earlier discuss with Christoph Hellwig https://lore.kernel.org/all/1632712920-8171-1-git-send-email-anshuman.khandual@xxxxxxx/ This series applies on 5.17-rc1 after the following patch. https://lore.kernel.org/all/1643004823-16441-1-git-send-email-anshuman.khandual@xxxxxxx/ This has been cross built for multiple platforms. I would like to get some early feed back on this proposal. All reviews and suggestions welcome. Hello Christoph, I have taken the liberty to preserve your authorship on the x86 patch which is borrowed almost as is from our earlier discussion. I have also added you as 'Suggested-by:' on the patch that adds config ARCH_HAS_VM_GET_PAGE_PROT. Nonetheless please feel free to correct me for any other missing authorship attributes I should have added. Thank you. - Anshuman Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: linux-mm@xxxxxxxxx Cc: linux-kernel@xxxxxxxxxxxxxxx Anshuman Khandual (30): mm/debug_vm_pgtable: Directly use vm_get_page_prot() mm/mmap: Clarify protection_map[] indices mm/mmap: Add new config ARCH_HAS_VM_GET_PAGE_PROT powerpc/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT arm64/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT sparc/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT mips/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT m68k/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT arm/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT mm/mmap: Drop protection_map[] mm/mmap: Drop arch_filter_pgprot() mm/mmap: Drop arch_vm_get_page_pgprot() s390/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT riscv/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT alpha/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT sh/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT arc/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT csky/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT extensa/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT parisc/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT openrisc/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT um/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT microblaze/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT nios2/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT hexagon/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT nds32/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT ia64/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT mm/mmap: Drop generic vm_get_page_prot() mm/mmap: Drop ARCH_HAS_VM_GET_PAGE_PROT mm/mmap: Define macros for vm_flags access permission combinations Christoph Hellwig (1): x86/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT arch/alpha/include/asm/pgtable.h | 17 ----- arch/alpha/mm/init.c | 41 +++++++++++ arch/arc/include/asm/pgtable-bits-arcv2.h | 17 ----- arch/arc/mm/mmap.c | 41 +++++++++++ arch/arm/include/asm/pgtable.h | 18 ----- arch/arm/mm/mmu.c | 50 +++++++++++-- arch/arm64/Kconfig | 1 - arch/arm64/include/asm/mman.h | 3 +- arch/arm64/include/asm/pgtable-prot.h | 18 ----- arch/arm64/include/asm/pgtable.h | 2 +- arch/arm64/mm/mmap.c | 50 +++++++++++++ arch/csky/include/asm/pgtable.h | 18 ----- arch/csky/mm/init.c | 41 +++++++++++ arch/hexagon/include/asm/pgtable.h | 24 ------- arch/hexagon/mm/init.c | 42 +++++++++++ arch/ia64/include/asm/pgtable.h | 17 ----- arch/ia64/mm/init.c | 43 ++++++++++- arch/m68k/include/asm/mcf_pgtable.h | 59 --------------- arch/m68k/include/asm/motorola_pgtable.h | 22 ------ arch/m68k/include/asm/sun3_pgtable.h | 22 ------ arch/m68k/mm/init.c | 87 +++++++++++++++++++++++ arch/m68k/mm/motorola.c | 44 +++++++++++- arch/microblaze/include/asm/pgtable.h | 17 ----- arch/microblaze/mm/init.c | 41 +++++++++++ arch/mips/include/asm/pgtable.h | 22 ------ arch/mips/mm/cache.c | 65 ++++++++++------- arch/nds32/include/asm/pgtable.h | 17 ----- arch/nds32/mm/mmap.c | 41 +++++++++++ arch/nios2/include/asm/pgtable.h | 16 ----- arch/nios2/mm/init.c | 41 +++++++++++ arch/openrisc/include/asm/pgtable.h | 18 ----- arch/openrisc/mm/init.c | 41 +++++++++++ arch/parisc/include/asm/pgtable.h | 20 ------ arch/parisc/mm/init.c | 41 +++++++++++ arch/powerpc/include/asm/mman.h | 3 +- arch/powerpc/include/asm/pgtable.h | 19 ----- arch/powerpc/mm/mmap.c | 47 ++++++++++++ arch/riscv/include/asm/pgtable.h | 16 ----- arch/riscv/mm/init.c | 41 +++++++++++ arch/s390/include/asm/pgtable.h | 17 ----- arch/s390/mm/mmap.c | 41 +++++++++++ arch/sh/include/asm/pgtable.h | 17 ----- arch/sh/mm/mmap.c | 43 +++++++++++ arch/sparc/include/asm/mman.h | 1 - arch/sparc/include/asm/pgtable_32.h | 19 ----- arch/sparc/include/asm/pgtable_64.h | 19 ----- arch/sparc/mm/init_32.c | 41 +++++++++++ arch/sparc/mm/init_64.c | 71 +++++++++++++----- arch/um/include/asm/pgtable.h | 17 ----- arch/um/kernel/mem.c | 41 +++++++++++ arch/x86/Kconfig | 1 - arch/x86/include/asm/pgtable.h | 5 -- arch/x86/include/asm/pgtable_types.h | 19 ----- arch/x86/include/uapi/asm/mman.h | 14 ---- arch/x86/mm/Makefile | 2 +- arch/x86/mm/mem_encrypt_amd.c | 4 -- arch/x86/mm/pgprot.c | 71 ++++++++++++++++++ arch/xtensa/include/asm/pgtable.h | 18 ----- arch/xtensa/mm/init.c | 41 +++++++++++ include/linux/mm.h | 45 ++++++++++-- include/linux/mman.h | 4 -- mm/Kconfig | 3 - mm/debug_vm_pgtable.c | 27 +++---- mm/mmap.c | 22 ------ 64 files changed, 1150 insertions(+), 636 deletions(-) create mode 100644 arch/x86/mm/pgprot.c -- 2.25.1
