| Message ID | 20221024003541.1347364-1-rmclure@linux.ibm.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v3,1/3] powerpc: Add common pud_pfn stub for all platforms | expand |
Le 24/10/2022 à 02:35, 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. > > 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> > --- > V2: Remove conditional BUILD_BUG and BUG. Instead warn on usage. > --- > arch/powerpc/include/asm/book3s/64/pgtable.h | 10 ---------- > arch/powerpc/include/asm/pgtable.h | 14 ++++++++++++++ > 2 files changed, 14 insertions(+), 10 deletions(-) > > diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h > index 486902aff040..f9aefa492df0 100644 > --- a/arch/powerpc/include/asm/book3s/64/pgtable.h > +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h > @@ -1413,16 +1413,6 @@ static inline int pgd_devmap(pgd_t pgd) > } > #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ > > -static inline int pud_pfn(pud_t pud) > -{ > - /* > - * Currently all calls to pud_pfn() are gated around a pud_devmap() > - * check so this should never be used. If it grows another user we > - * want to know about it. > - */ > - BUILD_BUG(); > - return 0; > -} > #define __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION > pte_t ptep_modify_prot_start(struct vm_area_struct *, unsigned long, pte_t *); > void ptep_modify_prot_commit(struct vm_area_struct *, unsigned long, > diff --git a/arch/powerpc/include/asm/pgtable.h b/arch/powerpc/include/asm/pgtable.h > index 33f4bf8d22b0..36956fb440e1 100644 > --- a/arch/powerpc/include/asm/pgtable.h > +++ b/arch/powerpc/include/asm/pgtable.h > @@ -158,6 +158,20 @@ struct seq_file; > void arch_report_meminfo(struct seq_file *m); > #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(1, "pud: platform does not use pud entries directly"); Would a WARN_ONCE() be enough ? > + return 0; > +} > +#endif > + > #endif /* __ASSEMBLY__ */ > > #endif /* _ASM_POWERPC_PGTABLE_H */
diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h index 486902aff040..f9aefa492df0 100644 --- a/arch/powerpc/include/asm/book3s/64/pgtable.h +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h @@ -1413,16 +1413,6 @@ static inline int pgd_devmap(pgd_t pgd) } #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ -static inline int pud_pfn(pud_t pud) -{ - /* - * Currently all calls to pud_pfn() are gated around a pud_devmap() - * check so this should never be used. If it grows another user we - * want to know about it. - */ - BUILD_BUG(); - return 0; -} #define __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION pte_t ptep_modify_prot_start(struct vm_area_struct *, unsigned long, pte_t *); void ptep_modify_prot_commit(struct vm_area_struct *, unsigned long, diff --git a/arch/powerpc/include/asm/pgtable.h b/arch/powerpc/include/asm/pgtable.h index 33f4bf8d22b0..36956fb440e1 100644 --- a/arch/powerpc/include/asm/pgtable.h +++ b/arch/powerpc/include/asm/pgtable.h @@ -158,6 +158,20 @@ struct seq_file; void arch_report_meminfo(struct seq_file *m); #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(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> --- V2: Remove conditional BUILD_BUG and BUG. Instead warn on usage. --- arch/powerpc/include/asm/book3s/64/pgtable.h | 10 ---------- arch/powerpc/include/asm/pgtable.h | 14 ++++++++++++++ 2 files changed, 14 insertions(+), 10 deletions(-)