Messages in this thread | | | From | Paul Burton <> | Subject | Re: [PATCH v10 05/22] mips: mm: Add p?d_leaf() definitions | Date | Wed, 31 Jul 2019 18:35:54 +0000 |
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Hi Steven,
On Wed, Jul 31, 2019 at 04:45:46PM +0100, Steven Price wrote: > walk_page_range() is going to be allowed to walk page tables other than > those of user space. For this it needs to know when it has reached a > 'leaf' entry in the page tables. This information is provided by the > p?d_leaf() functions/macros. > > If _PAGE_HUGE is defined we can simply look for it. When not defined we > can be confident that there are no leaf pages in existence and fall back > on the generic implementation (added in a later patch) which returns 0. > > CC: Ralf Baechle <ralf@linux-mips.org> > CC: Paul Burton <paul.burton@mips.com> > CC: James Hogan <jhogan@kernel.org> > CC: linux-mips@vger.kernel.org > Signed-off-by: Steven Price <steven.price@arm.com>
Acked-by: Paul Burton <paul.burton@mips.com>
Thanks, Paul
> --- > arch/mips/include/asm/pgtable.h | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h > index 7d27194e3b45..238ca243ad31 100644 > --- a/arch/mips/include/asm/pgtable.h > +++ b/arch/mips/include/asm/pgtable.h > @@ -627,6 +627,11 @@ static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm, > > #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ > > +#ifdef _PAGE_HUGE > +#define pmd_leaf(pmd) ((pmd_val(pmd) & _PAGE_HUGE) != 0) > +#define pud_leaf(pud) ((pud_val(pud) & _PAGE_HUGE) != 0) > +#endif > + > #define gup_fast_permitted(start, end) (!cpu_has_dc_aliases) > > #include <asm-generic/pgtable.h> > -- > 2.20.1 >
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