Message ID | 20231130025404.37179-6-rmclure@linux.ibm.com (mailing list archive) |
---|---|
State | Changes Requested |
Headers | show |
Series | Support page table check | expand |
Le 30/11/2023 à 03:53, Rohan McLure a écrit : > Prior to this commit, pud_pfn was implemented with BUILD_BUG as the inline > function for 64-bit Book3S systems but is never included, as its > invocations in generic code are guarded by calls to pud_devmap which return > zero on such systems. A future patch will provide support for page table > checks, the generic code for which depends on a pud_pfn stub being > implemented, even while the patch will not interact with puds directly. This is not correct anymore, that was changed by commit 27af67f35631 ("powerpc/book3s64/mm: enable transparent pud hugepage") > > Remove the 64-bit Book3S stub and define pud_pfn to warn on all > platforms. pud_pfn may be defined properly on a per-platform basis > should it grow real usages in future. Your patch removes nothing, it just adds a fallback, is that still correct ? > > Signed-off-by: Rohan McLure <rmclure@linux.ibm.com> > --- > arch/powerpc/include/asm/pgtable.h | 14 ++++++++++++++ > 1 file changed, 14 insertions(+) > > diff --git a/arch/powerpc/include/asm/pgtable.h b/arch/powerpc/include/asm/pgtable.h > index db0231afca9d..9c0f2151f08f 100644 > --- a/arch/powerpc/include/asm/pgtable.h > +++ b/arch/powerpc/include/asm/pgtable.h > @@ -219,6 +219,20 @@ static inline bool arch_supports_memmap_on_memory(unsigned long vmemmap_size) > > #endif /* CONFIG_PPC64 */ > > +/* > + * Currently only consumed by page_table_check_pud_{set,clear}. Since clears > + * and sets to page table entries at any level are done through > + * page_table_check_pte_{set,clear}, provide stub implementation. > + */ > +#ifndef pud_pfn > +#define pud_pfn pud_pfn > +static inline int pud_pfn(pud_t pud) > +{ > + WARN_ONCE(1, "pud: platform does not use pud entries directly"); > + return 0; > +} > +#endif > + > #endif /* __ASSEMBLY__ */ > > #endif /* _ASM_POWERPC_PGTABLE_H */
diff --git a/arch/powerpc/include/asm/pgtable.h b/arch/powerpc/include/asm/pgtable.h index db0231afca9d..9c0f2151f08f 100644 --- a/arch/powerpc/include/asm/pgtable.h +++ b/arch/powerpc/include/asm/pgtable.h @@ -219,6 +219,20 @@ static inline bool arch_supports_memmap_on_memory(unsigned long vmemmap_size) #endif /* CONFIG_PPC64 */ +/* + * Currently only consumed by page_table_check_pud_{set,clear}. Since clears + * and sets to page table entries at any level are done through + * page_table_check_pte_{set,clear}, provide stub implementation. + */ +#ifndef pud_pfn +#define pud_pfn pud_pfn +static inline int pud_pfn(pud_t pud) +{ + WARN_ONCE(1, "pud: platform does not use pud entries directly"); + return 0; +} +#endif + #endif /* __ASSEMBLY__ */ #endif /* _ASM_POWERPC_PGTABLE_H */
Prior to this commit, pud_pfn was implemented with BUILD_BUG as the inline function for 64-bit Book3S systems but is never included, as its invocations in generic code are guarded by calls to pud_devmap which return zero on such systems. A future patch will provide support for page table checks, the generic code for which depends on a pud_pfn stub being implemented, even while the patch will not interact with puds directly. Remove the 64-bit Book3S stub and define pud_pfn to warn on all platforms. pud_pfn may be defined properly on a per-platform basis should it grow real usages in future. Signed-off-by: Rohan McLure <rmclure@linux.ibm.com> --- arch/powerpc/include/asm/pgtable.h | 14 ++++++++++++++ 1 file changed, 14 insertions(+)