Re: [PATCH 03/13] mm: Add generic p?d_large() macros

Peter Zijlstra
2019-02-18T11:31:50Z

On Fri, Feb 15, 2019 at 05:02:24PM +0000, Steven Price wrote:
> From: James Morse <james.morse@arm.com>
>
> Exposing the pud/pgd levels of the page tables to walk_page_range() means
> we may come across the exotic large mappings that come with large areas
> of contiguous memory (such as the kernel's linear map).
>
> For architectures that don't provide p?d_large() macros, provided a
> does nothing default.

Kan was going to fix that for all archs I think..

See:

http://lkml.kernel.org/r/20190204105409.GA17550@hirez.programming.kicks-ass.net

> Signed-off-by: James Morse <james.morse@arm.com>
> Signed-off-by: Steven Price <steven.price@arm.com>
> ---
> include/asm-generic/pgtable.h | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
> diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h
> index 05e61e6c843f..7630d663cd51 100644
> --- a/include/asm-generic/pgtable.h
> +++ b/include/asm-generic/pgtable.h
> @@ -1186,4 +1186,14 @@ static inline bool arch_has_pfn_modify_check(void)
> #define mm_pmd_folded(mm) __is_defined(__PAGETABLE_PMD_FOLDED)
> #endif
>
> +#ifndef pgd_large
> +#define pgd_large(x) 0
> +#endif
> +#ifndef pud_large
> +#define pud_large(x) 0
> +#endif
> +#ifndef pmd_large
> +#define pmd_large(x) 0
> +#endif
> +
> #endif /* _ASM_GENERIC_PGTABLE_H */
> --
> 2.20.1
>