Re: [PATCH V4 10/26] openrisc/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT

Stafford Horne
2022-06-25T04:05:01Z

On Fri, Jun 24, 2022 at 10:13:23AM +0530, Anshuman Khandual wrote:
> This enables ARCH_HAS_VM_GET_PAGE_PROT on the platform and exports standard
> vm_get_page_prot() implementation via DECLARE_VM_GET_PAGE_PROT, which looks
> up a private and static protection_map[] array. Subsequently all __SXXX and
> __PXXX macros can be dropped which are no longer needed.
>
> Cc: Jonas Bonn <jonas@southpole.se>
> Cc: openrisc@lists.librecores.org
> Cc: linux-kernel@vger.kernel.org
> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
> ---
> arch/openrisc/Kconfig | 1 +
> arch/openrisc/include/asm/pgtable.h | 18 ------------------
> arch/openrisc/mm/init.c | 20 ++++++++++++++++++++
> 3 files changed, 21 insertions(+), 18 deletions(-)
>
> diff --git a/arch/openrisc/Kconfig b/arch/openrisc/Kconfig
> index e814df4c483c..fe0dfb50eb86 100644
> --- a/arch/openrisc/Kconfig
> +++ b/arch/openrisc/Kconfig
> @@ -10,6 +10,7 @@ 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/openrisc/include/asm/pgtable.h b/arch/openrisc/include/asm/pgtable.h
> index c3abbf71e09f..dcae8aea132f 100644
> --- a/arch/openrisc/include/asm/pgtable.h
> +++ b/arch/openrisc/include/asm/pgtable.h
> @@ -176,24 +176,6 @@ extern void paging_init(void);
> __pgprot(_PAGE_ALL | _PAGE_SRE | _PAGE_SWE \
> | _PAGE_SHARED | _PAGE_DIRTY | _PAGE_EXEC | _PAGE_CI)
>
> -#define __P000 PAGE_NONE
> -#define __P001 PAGE_READONLY_X
> -#define __P010 PAGE_COPY
> -#define __P011 PAGE_COPY_X
> -#define __P100 PAGE_READONLY
> -#define __P101 PAGE_READONLY_X
> -#define __P110 PAGE_COPY
> -#define __P111 PAGE_COPY_X
> -
> -#define __S000 PAGE_NONE
> -#define __S001 PAGE_READONLY_X
> -#define __S010 PAGE_SHARED
> -#define __S011 PAGE_SHARED_X
> -#define __S100 PAGE_READONLY
> -#define __S101 PAGE_READONLY_X
> -#define __S110 PAGE_SHARED
> -#define __S111 PAGE_SHARED_X
> -
> /* zero page used for uninitialized stuff */
> extern unsigned long empty_zero_page[2048];
> #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
> diff --git a/arch/openrisc/mm/init.c b/arch/openrisc/mm/init.c
> index 3a021ab6f1ae..a654b9dcba91 100644
> --- a/arch/openrisc/mm/init.c
> +++ b/arch/openrisc/mm/init.c
> @@ -208,3 +208,23 @@ void __init mem_init(void)
> mem_init_done = 1;
> return;
> }
> +
> +static pgprot_t protection_map[16] __ro_after_init = {
> + [VM_NONE] = PAGE_NONE,
> + [VM_READ] = PAGE_READONLY_X,
> + [VM_WRITE] = PAGE_COPY,
> + [VM_WRITE | VM_READ] = PAGE_COPY_X,
> + [VM_EXEC] = PAGE_READONLY,
> + [VM_EXEC | VM_READ] = PAGE_READONLY_X,
> + [VM_EXEC | VM_WRITE] = PAGE_COPY,
> + [VM_EXEC | VM_WRITE | VM_READ] = PAGE_COPY_X,
> + [VM_SHARED] = PAGE_NONE,
> + [VM_SHARED | VM_READ] = PAGE_READONLY_X,
> + [VM_SHARED | VM_WRITE] = PAGE_SHARED,
> + [VM_SHARED | VM_WRITE | VM_READ] = PAGE_SHARED_X,
> + [VM_SHARED | VM_EXEC] = PAGE_READONLY,
> + [VM_SHARED | VM_EXEC | VM_READ] = PAGE_READONLY_X,
> + [VM_SHARED | VM_EXEC | VM_WRITE] = PAGE_SHARED,
> + [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = PAGE_SHARED_X
> +};
> +DECLARE_VM_GET_PAGE_PROT

Looks good.

Acked-by: Stafford Horne <shorne@gmail.com>