| Message ID | 20200108202448.9669-6-sean.j.christopherson@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: x86/mmu: Huge page fixes, cleanup, and DAX | expand |
Sean Christopherson <sean.j.christopherson@intel.com> writes: > diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h > index b5e49e6bac63..400ac8da75e8 100644 > --- a/arch/x86/include/asm/pgtable_types.h > +++ b/arch/x86/include/asm/pgtable_types.h > @@ -561,6 +561,10 @@ static inline void update_page_count(int level, unsigned long pages) { } > extern pte_t *lookup_address(unsigned long address, unsigned int *level); > extern pte_t *lookup_address_in_pgd(pgd_t *pgd, unsigned long address, > unsigned int *level); > + > +struct mm_struct; > +pte_t *lookup_address_in_mm(struct mm_struct *mm, unsigned long address, > + unsigned int *level); Please keep the file consistent and use extern even if not required. Other than that: Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
On 09/01/20 22:04, Thomas Gleixner wrote: > Sean Christopherson <sean.j.christopherson@intel.com> writes: > >> diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h >> index b5e49e6bac63..400ac8da75e8 100644 >> --- a/arch/x86/include/asm/pgtable_types.h >> +++ b/arch/x86/include/asm/pgtable_types.h >> @@ -561,6 +561,10 @@ static inline void update_page_count(int level, unsigned long pages) { } >> extern pte_t *lookup_address(unsigned long address, unsigned int *level); >> extern pte_t *lookup_address_in_pgd(pgd_t *pgd, unsigned long address, >> unsigned int *level); >> + >> +struct mm_struct; >> +pte_t *lookup_address_in_mm(struct mm_struct *mm, unsigned long address, >> + unsigned int *level); > > Please keep the file consistent and use extern even if not required. > > Other than that: > > Reviewed-by: Thomas Gleixner <tglx@linutronix.de> > Adjusted, thanks for the review. Paolo
diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h index b5e49e6bac63..400ac8da75e8 100644 --- a/arch/x86/include/asm/pgtable_types.h +++ b/arch/x86/include/asm/pgtable_types.h @@ -561,6 +561,10 @@ static inline void update_page_count(int level, unsigned long pages) { } extern pte_t *lookup_address(unsigned long address, unsigned int *level); extern pte_t *lookup_address_in_pgd(pgd_t *pgd, unsigned long address, unsigned int *level); + +struct mm_struct; +pte_t *lookup_address_in_mm(struct mm_struct *mm, unsigned long address, + unsigned int *level); extern pmd_t *lookup_pmd_address(unsigned long address); extern phys_addr_t slow_virt_to_phys(void *__address); extern int __init kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index 0d09cc5aad61..8787fec876e4 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -618,6 +618,17 @@ pte_t *lookup_address(unsigned long address, unsigned int *level) } EXPORT_SYMBOL_GPL(lookup_address); +/* + * Lookup the page table entry for a virtual address in a given mm. Return a + * pointer to the entry and the level of the mapping. + */ +pte_t *lookup_address_in_mm(struct mm_struct *mm, unsigned long address, + unsigned int *level) +{ + return lookup_address_in_pgd(pgd_offset(mm, address), address, level); +} +EXPORT_SYMBOL_GPL(lookup_address_in_mm); + static pte_t *_lookup_address_cpa(struct cpa_data *cpa, unsigned long address, unsigned int *level) {
Add a helper, lookup_address_in_mm(), to traverse the page tables of a given mm struct. KVM will use the helper to retrieve the host mapping level, e.g. 4k vs. 2mb vs. 1gb, of a compound (or DAX-backed) page without having to resort to implementation specific metadata. E.g. KVM currently uses different logic for HugeTLB vs. THP, and would add a third variant for DAX-backed files. Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> --- arch/x86/include/asm/pgtable_types.h | 4 ++++ arch/x86/mm/pageattr.c | 11 +++++++++++ 2 files changed, 15 insertions(+)