| Message ID | 20230315051444.3229621-6-willy@infradead.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | New page table range API | expand |
On Wed, Mar 15, 2023 at 05:14:13AM +0000, Matthew Wilcox (Oracle) wrote: > Most architectures can just define set_pte() and PFN_PTE_SHIFT to > use this definition. It's also a handy spot to document the guarantees > provided by the MM. > > Suggested-by: Mike Rapoport (IBM) <rppt@kernel.org> > Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org> > --- > include/linux/pgtable.h | 37 +++++++++++++++++++++++++++++++++++++ > 1 file changed, 37 insertions(+) > > diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h > index c5a51481bbb9..a755fe94b4b4 100644 > --- a/include/linux/pgtable.h > +++ b/include/linux/pgtable.h > @@ -172,6 +172,43 @@ static inline int pmd_young(pmd_t pmd) > } > #endif > > +#ifndef set_ptes > +#ifdef PFN_PTE_SHIFT > +/** > + * set_ptes - Map consecutive pages to a contiguous range of addresses. > + * @mm: Address space to map the pages into. > + * @addr: Address to map the first page at. > + * @ptep: Page table pointer for the first entry. > + * @pte: Page table entry for the first page. > + * @nr: Number of pages to map. > + * > + * May be overridden by the architecture, or the architecture can define > + * set_pte() and PFN_PTE_SHIFT. > + * > + * Context: The caller holds the page table lock. The pages all belong > + * to the same folio. The PTEs are all in the same PMD. > + */ > +static inline void set_ptes(struct mm_struct *mm, unsigned long addr, > + pte_t *ptep, pte_t pte, unsigned int nr) > +{ > + page_table_check_ptes_set(mm, addr, ptep, pte, nr); > + > + for (;;) { > + set_pte(ptep, pte); > + if (--nr == 0) > + break; > + ptep++; > + pte = __pte(pte_val(pte) + (1UL << PFN_PTE_SHIFT)); > + } > +} > +#ifndef set_pte_at > +#define set_pte_at(mm, addr, ptep, pte) set_ptes(mm, addr, ptep, pte, 1) > +#endif > +#endif > +#else > +#define set_pte_at(mm, addr, ptep, pte) set_ptes(mm, addr, ptep, pte, 1) > +#endif > + > #ifndef __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS > extern int ptep_set_access_flags(struct vm_area_struct *vma, > unsigned long address, pte_t *ptep, > -- > 2.39.2 >
On 3/15/23 10:44, Matthew Wilcox (Oracle) wrote: > Most architectures can just define set_pte() and PFN_PTE_SHIFT to > use this definition. It's also a handy spot to document the guarantees > provided by the MM. > > Suggested-by: Mike Rapoport (IBM) <rppt@kernel.org> > Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> > --- > include/linux/pgtable.h | 37 +++++++++++++++++++++++++++++++++++++ > 1 file changed, 37 insertions(+) > > diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h > index c5a51481bbb9..a755fe94b4b4 100644 > --- a/include/linux/pgtable.h > +++ b/include/linux/pgtable.h > @@ -172,6 +172,43 @@ static inline int pmd_young(pmd_t pmd) > } > #endif > > +#ifndef set_ptes > +#ifdef PFN_PTE_SHIFT > +/** > + * set_ptes - Map consecutive pages to a contiguous range of addresses. > + * @mm: Address space to map the pages into. > + * @addr: Address to map the first page at. > + * @ptep: Page table pointer for the first entry. > + * @pte: Page table entry for the first page. > + * @nr: Number of pages to map. > + * > + * May be overridden by the architecture, or the architecture can define > + * set_pte() and PFN_PTE_SHIFT. > + * > + * Context: The caller holds the page table lock. The pages all belong > + * to the same folio. The PTEs are all in the same PMD. > + */ > +static inline void set_ptes(struct mm_struct *mm, unsigned long addr, > + pte_t *ptep, pte_t pte, unsigned int nr) > +{ > + page_table_check_ptes_set(mm, addr, ptep, pte, nr); > + > + for (;;) { > + set_pte(ptep, pte); > + if (--nr == 0) > + break; > + ptep++; > + pte = __pte(pte_val(pte) + (1UL << PFN_PTE_SHIFT)); > + } > +} > +#ifndef set_pte_at > +#define set_pte_at(mm, addr, ptep, pte) set_ptes(mm, addr, ptep, pte, 1) > +#endif Should not there be a build phase call out when both set_ptes() and PFN_PTE_SHIFT are not defined on a given platform ? --- a/include/linux/pgtable.h +++ b/include/linux/pgtable.h @@ -204,6 +204,8 @@ static inline void set_ptes(struct mm_struct *mm, unsigned long addr, #ifndef set_pte_at #define set_pte_at(mm, addr, ptep, pte) set_ptes(mm, addr, ptep, pte, 1) #endif +#else +#error "You should define PFN_PTE_SHIFT" #endif #else #define set_pte_at(mm, addr, ptep, pte) set_ptes(mm, addr, ptep, pte, 1) > +#endif> +#else > +#define set_pte_at(mm, addr, ptep, pte) set_ptes(mm, addr, ptep, pte, 1) > +#endif > + > #ifndef __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS > extern int ptep_set_access_flags(struct vm_area_struct *vma, > unsigned long address, pte_t *ptep,
On Thu, May 25, 2023 at 08:31:14AM +0530, Anshuman Khandual wrote: > > +#ifndef set_ptes > > +#ifdef PFN_PTE_SHIFT > > +/** > > + * set_ptes - Map consecutive pages to a contiguous range of addresses. > > + * @mm: Address space to map the pages into. > > + * @addr: Address to map the first page at. > > + * @ptep: Page table pointer for the first entry. > > + * @pte: Page table entry for the first page. > > + * @nr: Number of pages to map. > > + * > > + * May be overridden by the architecture, or the architecture can define > > + * set_pte() and PFN_PTE_SHIFT. > > + * > > + * Context: The caller holds the page table lock. The pages all belong > > + * to the same folio. The PTEs are all in the same PMD. > > + */ > > +static inline void set_ptes(struct mm_struct *mm, unsigned long addr, > > + pte_t *ptep, pte_t pte, unsigned int nr) > > +{ > > + page_table_check_ptes_set(mm, addr, ptep, pte, nr); > > + > > + for (;;) { > > + set_pte(ptep, pte); > > + if (--nr == 0) > > + break; > > + ptep++; > > + pte = __pte(pte_val(pte) + (1UL << PFN_PTE_SHIFT)); > > + } > > +} > > +#ifndef set_pte_at > > +#define set_pte_at(mm, addr, ptep, pte) set_ptes(mm, addr, ptep, pte, 1) > > +#endif > > Should not there be a build phase call out when both set_ptes() and PFN_PTE_SHIFT > are not defined on a given platform ? How does that help? Either way you get a clear build error.
diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h index c5a51481bbb9..a755fe94b4b4 100644 --- a/include/linux/pgtable.h +++ b/include/linux/pgtable.h @@ -172,6 +172,43 @@ static inline int pmd_young(pmd_t pmd) } #endif +#ifndef set_ptes +#ifdef PFN_PTE_SHIFT +/** + * set_ptes - Map consecutive pages to a contiguous range of addresses. + * @mm: Address space to map the pages into. + * @addr: Address to map the first page at. + * @ptep: Page table pointer for the first entry. + * @pte: Page table entry for the first page. + * @nr: Number of pages to map. + * + * May be overridden by the architecture, or the architecture can define + * set_pte() and PFN_PTE_SHIFT. + * + * Context: The caller holds the page table lock. The pages all belong + * to the same folio. The PTEs are all in the same PMD. + */ +static inline void set_ptes(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, pte_t pte, unsigned int nr) +{ + page_table_check_ptes_set(mm, addr, ptep, pte, nr); + + for (;;) { + set_pte(ptep, pte); + if (--nr == 0) + break; + ptep++; + pte = __pte(pte_val(pte) + (1UL << PFN_PTE_SHIFT)); + } +} +#ifndef set_pte_at +#define set_pte_at(mm, addr, ptep, pte) set_ptes(mm, addr, ptep, pte, 1) +#endif +#endif +#else +#define set_pte_at(mm, addr, ptep, pte) set_ptes(mm, addr, ptep, pte, 1) +#endif + #ifndef __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS extern int ptep_set_access_flags(struct vm_area_struct *vma, unsigned long address, pte_t *ptep,
Most architectures can just define set_pte() and PFN_PTE_SHIFT to use this definition. It's also a handy spot to document the guarantees provided by the MM. Suggested-by: Mike Rapoport (IBM) <rppt@kernel.org> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> --- include/linux/pgtable.h | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+)