* [PATCH v10 05/22] mips: mm: Add p?d_leaf() definitions [not found] <20190731154603.41797-1-steven.price@arm.com> @ 2019-07-31 15:45 ` Steven Price 2019-07-31 18:35 ` Paul Burton 0 siblings, 1 reply; 2+ messages in thread From: Steven Price @ 2019-07-31 15:45 UTC (permalink / raw) To: linux-mm Cc: Steven Price, Andy Lutomirski, Ard Biesheuvel, Arnd Bergmann, Borislav Petkov, Catalin Marinas, Dave Hansen, Ingo Molnar, James Morse, Jérôme Glisse, Peter Zijlstra, Thomas Gleixner, Will Deacon, x86, H. Peter Anvin, linux-arm-kernel, linux-kernel, Mark Rutland, Liang, Kan, Andrew Morton, Ralf Baechle, Paul Burton, James Hogan, linux-mips 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> --- 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 ^ permalink raw reply related [flat|nested] 2+ messages in thread
* Re: [PATCH v10 05/22] mips: mm: Add p?d_leaf() definitions 2019-07-31 15:45 ` [PATCH v10 05/22] mips: mm: Add p?d_leaf() definitions Steven Price @ 2019-07-31 18:35 ` Paul Burton 0 siblings, 0 replies; 2+ messages in thread From: Paul Burton @ 2019-07-31 18:35 UTC (permalink / raw) To: Steven Price Cc: linux-mm, Andy Lutomirski, Ard Biesheuvel, Arnd Bergmann, Borislav Petkov, Catalin Marinas, Dave Hansen, Ingo Molnar, James Morse, Jérôme Glisse, Peter Zijlstra, Thomas Gleixner, Will Deacon, x86, H. Peter Anvin, linux-arm-kernel, linux-kernel, Mark Rutland, Liang, Kan, Andrew Morton, Ralf Baechle, James Hogan, linux-mips 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 > ^ permalink raw reply [flat|nested] 2+ messages in thread
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2019-07-31 15:45 ` [PATCH v10 05/22] mips: mm: Add p?d_leaf() definitions Steven Price
2019-07-31 18:35 ` Paul Burton
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