Re: [PATCH v4 27/36] x86: Implement the new page table range API

From: Mike Rapoport
Date: Wed Mar 15 2023 - 07:18:30 EST


On Wed, Mar 15, 2023 at 11:34:36AM +0100, Peter Zijlstra wrote:
> On Wed, Mar 15, 2023 at 05:14:35AM +0000, Matthew Wilcox (Oracle) wrote:
> > Add PFN_PTE_SHIFT and a noop update_mmu_cache_range().
> >
> > Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
> > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> > Cc: Ingo Molnar <mingo@xxxxxxxxxx>
> > Cc: Borislav Petkov <bp@xxxxxxxxx>
> > Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
> > Cc: x86@xxxxxxxxxx
> > Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
> > ---
> > arch/x86/include/asm/pgtable.h | 13 ++++++-------
> > 1 file changed, 6 insertions(+), 7 deletions(-)
> >
> > diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
> > index 1031025730d0..b237878061c4 100644
> > --- a/arch/x86/include/asm/pgtable.h
> > +++ b/arch/x86/include/asm/pgtable.h
> > @@ -184,6 +184,8 @@ static inline int pte_special(pte_t pte)
> >
> > static inline u64 protnone_mask(u64 val);
> >
> > +#define PFN_PTE_SHIFT PAGE_SHIFT
> > +
> > static inline unsigned long pte_pfn(pte_t pte)
> > {
> > phys_addr_t pfn = pte_val(pte);
> > @@ -1019,13 +1021,6 @@ static inline pud_t native_local_pudp_get_and_clear(pud_t *pudp)
> > return res;
> > }
> >
> > -static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
> > - pte_t *ptep, pte_t pte)
> > -{
> > - page_table_check_ptes_set(mm, addr, ptep, pte, 1);
> > - set_pte(ptep, pte);
> > -}
> > -
>
> And remove set_pte_at() apparently.. whut?!?

It's now in include/linux/pgtable.h

> > static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr,
> > pmd_t *pmdp, pmd_t pmd)
> > {
> > @@ -1291,6 +1286,10 @@ static inline void update_mmu_cache(struct vm_area_struct *vma,
> > unsigned long addr, pte_t *ptep)
> > {
> > }
> > +static inline void update_mmu_cache_range(struct vm_area_struct *vma,
> > + unsigned long addr, pte_t *ptep, unsigned int nr)
> > +{
> > +}
> > static inline void update_mmu_cache_pmd(struct vm_area_struct *vma,
> > unsigned long addr, pmd_t *pmd)
> > {
> > --
> > 2.39.2
> >
>

--
Sincerely yours,
Mike.