Re: [PATCH V4 26/26] mm/mmap: Drop ARCH_HAS_VM_GET_PAGE_PROT

From: Christophe Leroy
Date: Mon Jun 27 2022 - 01:48:54 EST




Le 24/06/2022 à 06:43, Anshuman Khandual a écrit :
> Now all the platforms enable ARCH_HAS_GET_PAGE_PROT. They define and export
> own vm_get_page_prot() whether custom or standard DECLARE_VM_GET_PAGE_PROT.
> Hence there is no need for default generic fallback for vm_get_page_prot().
> Just drop this fallback and also ARCH_HAS_GET_PAGE_PROT mechanism.
>
> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> Cc: linux-mm@xxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>

Reviewed-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>

> ---
> arch/alpha/Kconfig | 1 -
> arch/arc/Kconfig | 1 -
> arch/arm/Kconfig | 1 -
> arch/arm64/Kconfig | 1 -
> arch/csky/Kconfig | 1 -
> arch/hexagon/Kconfig | 1 -
> arch/ia64/Kconfig | 1 -
> arch/loongarch/Kconfig | 1 -
> arch/m68k/Kconfig | 1 -
> arch/microblaze/Kconfig | 1 -
> arch/mips/Kconfig | 1 -
> arch/nios2/Kconfig | 1 -
> arch/openrisc/Kconfig | 1 -
> arch/parisc/Kconfig | 1 -
> arch/powerpc/Kconfig | 1 -
> arch/riscv/Kconfig | 1 -
> arch/s390/Kconfig | 1 -
> arch/sh/Kconfig | 1 -
> arch/sparc/Kconfig | 1 -
> arch/um/Kconfig | 1 -
> arch/x86/Kconfig | 1 -
> arch/xtensa/Kconfig | 1 -
> include/linux/mm.h | 3 ---
> mm/Kconfig | 3 ---
> mm/mmap.c | 22 ----------------------
> 25 files changed, 50 deletions(-)
>
> diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig
> index db1c8b329461..7d0d26b5b3f5 100644
> --- a/arch/alpha/Kconfig
> +++ b/arch/alpha/Kconfig
> @@ -2,7 +2,6 @@
> config ALPHA
> bool
> default y
> - select ARCH_HAS_VM_GET_PAGE_PROT
> select ARCH_32BIT_USTAT_F_TINODE
> select ARCH_MIGHT_HAVE_PC_PARPORT
> select ARCH_MIGHT_HAVE_PC_SERIO
> diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
> index 8be56a5d8a9b..9e3653253ef2 100644
> --- a/arch/arc/Kconfig
> +++ b/arch/arc/Kconfig
> @@ -13,7 +13,6 @@ config ARC
> select ARCH_HAS_SETUP_DMA_OPS
> select ARCH_HAS_SYNC_DMA_FOR_CPU
> select ARCH_HAS_SYNC_DMA_FOR_DEVICE
> - select ARCH_HAS_VM_GET_PAGE_PROT
> select ARCH_SUPPORTS_ATOMIC_RMW if ARC_HAS_LLSC
> select ARCH_32BIT_OFF_T
> select BUILDTIME_TABLE_SORT
> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> index e153b6d4fc5b..7630ba9cb6cc 100644
> --- a/arch/arm/Kconfig
> +++ b/arch/arm/Kconfig
> @@ -24,7 +24,6 @@ config ARM
> select ARCH_HAS_SYNC_DMA_FOR_CPU if SWIOTLB || !MMU
> select ARCH_HAS_TEARDOWN_DMA_OPS if MMU
> select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
> - select ARCH_HAS_VM_GET_PAGE_PROT
> select ARCH_HAVE_CUSTOM_GPIO_H
> select ARCH_HAVE_NMI_SAFE_CMPXCHG if CPU_V7 || CPU_V7M || CPU_V6K
> select ARCH_HAS_GCOV_PROFILE_ALL
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index 1652a9800ebe..7030bf3f8d6f 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -45,7 +45,6 @@ config ARM64
> select ARCH_HAS_SYSCALL_WRAPPER
> select ARCH_HAS_TEARDOWN_DMA_OPS if IOMMU_SUPPORT
> select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
> - select ARCH_HAS_VM_GET_PAGE_PROT
> select ARCH_HAS_ZONE_DMA_SET if EXPERT
> select ARCH_HAVE_ELF_PROT
> select ARCH_HAVE_NMI_SAFE_CMPXCHG
> diff --git a/arch/csky/Kconfig b/arch/csky/Kconfig
> index 588b8a9c68ed..21d72b078eef 100644
> --- a/arch/csky/Kconfig
> +++ b/arch/csky/Kconfig
> @@ -6,7 +6,6 @@ config CSKY
> select ARCH_HAS_GCOV_PROFILE_ALL
> select ARCH_HAS_SYNC_DMA_FOR_CPU
> select ARCH_HAS_SYNC_DMA_FOR_DEVICE
> - select ARCH_HAS_VM_GET_PAGE_PROT
> select ARCH_USE_BUILTIN_BSWAP
> select ARCH_USE_QUEUED_RWLOCKS
> select ARCH_WANT_FRAME_POINTERS if !CPU_CK610 && $(cc-option,-mbacktrace)
> diff --git a/arch/hexagon/Kconfig b/arch/hexagon/Kconfig
> index bc4ceecd0588..54eadf265178 100644
> --- a/arch/hexagon/Kconfig
> +++ b/arch/hexagon/Kconfig
> @@ -6,7 +6,6 @@ config HEXAGON
> def_bool y
> select ARCH_32BIT_OFF_T
> select ARCH_HAS_SYNC_DMA_FOR_DEVICE
> - select ARCH_HAS_VM_GET_PAGE_PROT
> select ARCH_NO_PREEMPT
> select DMA_GLOBAL_POOL
> # Other pending projects/to-do items.
> diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig
> index 0510a5737711..cb93769a9f2a 100644
> --- a/arch/ia64/Kconfig
> +++ b/arch/ia64/Kconfig
> @@ -12,7 +12,6 @@ config IA64
> select ARCH_HAS_DMA_MARK_CLEAN
> select ARCH_HAS_STRNCPY_FROM_USER
> select ARCH_HAS_STRNLEN_USER
> - select ARCH_HAS_VM_GET_PAGE_PROT
> select ARCH_MIGHT_HAVE_PC_PARPORT
> select ARCH_MIGHT_HAVE_PC_SERIO
> select ACPI
> diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
> index fd07b8e760ee..1920d52653b4 100644
> --- a/arch/loongarch/Kconfig
> +++ b/arch/loongarch/Kconfig
> @@ -9,7 +9,6 @@ config LOONGARCH
> select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
> select ARCH_HAS_PHYS_TO_DMA
> select ARCH_HAS_PTE_SPECIAL
> - select ARCH_HAS_VM_GET_PAGE_PROT
> select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
> select ARCH_INLINE_READ_LOCK if !PREEMPTION
> select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
> diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig
> index 49aa0cf13e96..936cce42ae9a 100644
> --- a/arch/m68k/Kconfig
> +++ b/arch/m68k/Kconfig
> @@ -7,7 +7,6 @@ config M68K
> select ARCH_HAS_CURRENT_STACK_POINTER
> select ARCH_HAS_DMA_PREP_COHERENT if HAS_DMA && MMU && !COLDFIRE
> select ARCH_HAS_SYNC_DMA_FOR_DEVICE if HAS_DMA
> - select ARCH_HAS_VM_GET_PAGE_PROT
> select ARCH_HAVE_NMI_SAFE_CMPXCHG if RMW_INSNS
> select ARCH_MIGHT_HAVE_PC_PARPORT if ISA
> select ARCH_NO_PREEMPT if !COLDFIRE
> diff --git a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig
> index 15f91ba8a0c4..8cf429ad1c84 100644
> --- a/arch/microblaze/Kconfig
> +++ b/arch/microblaze/Kconfig
> @@ -7,7 +7,6 @@ config MICROBLAZE
> select ARCH_HAS_GCOV_PROFILE_ALL
> select ARCH_HAS_SYNC_DMA_FOR_CPU
> select ARCH_HAS_SYNC_DMA_FOR_DEVICE
> - select ARCH_HAS_VM_GET_PAGE_PROT
> select ARCH_MIGHT_HAVE_PC_PARPORT
> select ARCH_WANT_IPC_PARSE_VERSION
> select BUILDTIME_TABLE_SORT
> diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
> index d0b7eb11ec81..db09d45d59ec 100644
> --- a/arch/mips/Kconfig
> +++ b/arch/mips/Kconfig
> @@ -14,7 +14,6 @@ config MIPS
> select ARCH_HAS_STRNLEN_USER
> select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
> select ARCH_HAS_UBSAN_SANITIZE_ALL
> - select ARCH_HAS_VM_GET_PAGE_PROT
> select ARCH_HAS_GCOV_PROFILE_ALL
> select ARCH_KEEP_MEMBLOCK
> select ARCH_SUPPORTS_UPROBES
> diff --git a/arch/nios2/Kconfig b/arch/nios2/Kconfig
> index e0459dffd218..4167f1eb4cd8 100644
> --- a/arch/nios2/Kconfig
> +++ b/arch/nios2/Kconfig
> @@ -6,7 +6,6 @@ config NIOS2
> select ARCH_HAS_SYNC_DMA_FOR_CPU
> select ARCH_HAS_SYNC_DMA_FOR_DEVICE
> select ARCH_HAS_DMA_SET_UNCACHED
> - select ARCH_HAS_VM_GET_PAGE_PROT
> select ARCH_NO_SWAP
> select COMMON_CLK
> select TIMER_OF
> diff --git a/arch/openrisc/Kconfig b/arch/openrisc/Kconfig
> index fe0dfb50eb86..e814df4c483c 100644
> --- a/arch/openrisc/Kconfig
> +++ b/arch/openrisc/Kconfig
> @@ -10,7 +10,6 @@ config OPENRISC
> select ARCH_HAS_DMA_SET_UNCACHED
> select ARCH_HAS_DMA_CLEAR_UNCACHED
> select ARCH_HAS_SYNC_DMA_FOR_DEVICE
> - select ARCH_HAS_VM_GET_PAGE_PROT
> select COMMON_CLK
> select OF
> select OF_EARLY_FLATTREE
> diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig
> index 90eabc846f81..5f2448dc5a2b 100644
> --- a/arch/parisc/Kconfig
> +++ b/arch/parisc/Kconfig
> @@ -11,7 +11,6 @@ config PARISC
> select ARCH_HAS_ELF_RANDOMIZE
> select ARCH_HAS_STRICT_KERNEL_RWX
> select ARCH_HAS_UBSAN_SANITIZE_ALL
> - select ARCH_HAS_VM_GET_PAGE_PROT
> select ARCH_HAS_PTE_SPECIAL
> select ARCH_NO_SG_CHAIN
> select ARCH_SUPPORTS_HUGETLBFS if PA20
> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
> index 1035d172c7dd..250b8658b2d4 100644
> --- a/arch/powerpc/Kconfig
> +++ b/arch/powerpc/Kconfig
> @@ -140,7 +140,6 @@ config PPC
> select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
> select ARCH_HAS_UACCESS_FLUSHCACHE
> select ARCH_HAS_UBSAN_SANITIZE_ALL
> - select ARCH_HAS_VM_GET_PAGE_PROT
> select ARCH_HAVE_NMI_SAFE_CMPXCHG
> select ARCH_KEEP_MEMBLOCK
> select ARCH_MIGHT_HAVE_PC_PARPORT
> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index 583389d4e43a..32ffef9f6e5b 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -32,7 +32,6 @@ config RISCV
> select ARCH_HAS_STRICT_MODULE_RWX if MMU && !XIP_KERNEL
> select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
> select ARCH_HAS_UBSAN_SANITIZE_ALL
> - select ARCH_HAS_VM_GET_PAGE_PROT
> select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
> select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
> select ARCH_STACKWALK
> diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
> index c4481377ca83..91c0b80a8bf0 100644
> --- a/arch/s390/Kconfig
> +++ b/arch/s390/Kconfig
> @@ -81,7 +81,6 @@ config S390
> select ARCH_HAS_SYSCALL_WRAPPER
> select ARCH_HAS_UBSAN_SANITIZE_ALL
> select ARCH_HAS_VDSO_DATA
> - select ARCH_HAS_VM_GET_PAGE_PROT
> select ARCH_HAVE_NMI_SAFE_CMPXCHG
> select ARCH_INLINE_READ_LOCK
> select ARCH_INLINE_READ_LOCK_BH
> diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
> index 91f3ea325388..5f220e903e5a 100644
> --- a/arch/sh/Kconfig
> +++ b/arch/sh/Kconfig
> @@ -12,7 +12,6 @@ config SUPERH
> select ARCH_HAS_GCOV_PROFILE_ALL
> select ARCH_HAS_PTE_SPECIAL
> select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
> - select ARCH_HAS_VM_GET_PAGE_PROT
> select ARCH_HIBERNATION_POSSIBLE if MMU
> select ARCH_MIGHT_HAVE_PC_PARPORT
> select ARCH_WANT_IPC_PARSE_VERSION
> diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
> index 09f868613a4d..9c1cce74953a 100644
> --- a/arch/sparc/Kconfig
> +++ b/arch/sparc/Kconfig
> @@ -13,7 +13,6 @@ config 64BIT
> config SPARC
> bool
> default y
> - select ARCH_HAS_VM_GET_PAGE_PROT
> select ARCH_MIGHT_HAVE_PC_PARPORT if SPARC64 && PCI
> select ARCH_MIGHT_HAVE_PC_SERIO
> select DMA_OPS
> diff --git a/arch/um/Kconfig b/arch/um/Kconfig
> index 7fb43654e5b5..4ec22e156a2e 100644
> --- a/arch/um/Kconfig
> +++ b/arch/um/Kconfig
> @@ -10,7 +10,6 @@ config UML
> select ARCH_HAS_KCOV
> select ARCH_HAS_STRNCPY_FROM_USER
> select ARCH_HAS_STRNLEN_USER
> - select ARCH_HAS_VM_GET_PAGE_PROT
> select ARCH_NO_PREEMPT
> select HAVE_ARCH_AUDITSYSCALL
> select HAVE_ARCH_SECCOMP_FILTER
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index be0b95e51df6..841e4843d0c4 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -94,7 +94,6 @@ config X86
> select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
> select ARCH_HAS_SYSCALL_WRAPPER
> select ARCH_HAS_UBSAN_SANITIZE_ALL
> - select ARCH_HAS_VM_GET_PAGE_PROT
> select ARCH_HAS_DEBUG_WX
> select ARCH_HAS_ZONE_DMA_SET if EXPERT
> select ARCH_HAVE_NMI_SAFE_CMPXCHG
> diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
> index 4c0d83520ff1..0b0f0172cced 100644
> --- a/arch/xtensa/Kconfig
> +++ b/arch/xtensa/Kconfig
> @@ -11,7 +11,6 @@ config XTENSA
> select ARCH_HAS_DMA_SET_UNCACHED if MMU
> select ARCH_HAS_STRNCPY_FROM_USER if !KASAN
> select ARCH_HAS_STRNLEN_USER
> - select ARCH_HAS_VM_GET_PAGE_PROT
> select ARCH_USE_MEMTEST
> select ARCH_USE_QUEUED_RWLOCKS
> select ARCH_USE_QUEUED_SPINLOCKS
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index 70d900f6df43..d776a86be1d4 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -424,9 +424,6 @@ extern unsigned int kobjsize(const void *objp);
> * mapping from the currently active vm_flags protection bits (the
> * low four bits) to a page protection mask..
> */
> -#ifndef CONFIG_ARCH_HAS_VM_GET_PAGE_PROT
> -extern pgprot_t protection_map[16];
> -#endif
>
> #define DECLARE_VM_GET_PAGE_PROT \
> pgprot_t vm_get_page_prot(unsigned long vm_flags) \
> diff --git a/mm/Kconfig b/mm/Kconfig
> index 169e64192e48..f47d257a053b 100644
> --- a/mm/Kconfig
> +++ b/mm/Kconfig
> @@ -951,9 +951,6 @@ config ARCH_HAS_CURRENT_STACK_POINTER
> register alias named "current_stack_pointer", this config can be
> selected.
>
> -config ARCH_HAS_VM_GET_PAGE_PROT
> - bool
> -
> config ARCH_HAS_PTE_DEVMAP
> bool
>
> diff --git a/mm/mmap.c b/mm/mmap.c
> index 43db3bd49071..3557fe83d124 100644
> --- a/mm/mmap.c
> +++ b/mm/mmap.c
> @@ -101,28 +101,6 @@ static void unmap_region(struct mm_struct *mm,
> * w: (no) no
> * x: (yes) yes
> */
> -#ifndef CONFIG_ARCH_HAS_VM_GET_PAGE_PROT
> -pgprot_t protection_map[16] __ro_after_init = {
> - [VM_NONE] = __P000,
> - [VM_READ] = __P001,
> - [VM_WRITE] = __P010,
> - [VM_WRITE | VM_READ] = __P011,
> - [VM_EXEC] = __P100,
> - [VM_EXEC | VM_READ] = __P101,
> - [VM_EXEC | VM_WRITE] = __P110,
> - [VM_EXEC | VM_WRITE | VM_READ] = __P111,
> - [VM_SHARED] = __S000,
> - [VM_SHARED | VM_READ] = __S001,
> - [VM_SHARED | VM_WRITE] = __S010,
> - [VM_SHARED | VM_WRITE | VM_READ] = __S011,
> - [VM_SHARED | VM_EXEC] = __S100,
> - [VM_SHARED | VM_EXEC | VM_READ] = __S101,
> - [VM_SHARED | VM_EXEC | VM_WRITE] = __S110,
> - [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = __S111
> -};
> -DECLARE_VM_GET_PAGE_PROT
> -#endif /* CONFIG_ARCH_HAS_VM_GET_PAGE_PROT */
> -
> static pgprot_t vm_pgprot_modify(pgprot_t oldprot, unsigned long vm_flags)
> {
> return pgprot_modify(oldprot, vm_get_page_prot(vm_flags));