diff options
| -rw-r--r-- | include/asm-generic/pgtable.h | 13 | ||||
| -rw-r--r-- | include/asm-mips/pgtable.h | 2 | ||||
| -rw-r--r-- | mm/mremap.c | 6 |
3 files changed, 18 insertions, 3 deletions
diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h index f86c1e549466..ff28c8b31f58 100644 --- a/include/asm-generic/pgtable.h +++ b/include/asm-generic/pgtable.h @@ -158,6 +158,19 @@ static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addres #define lazy_mmu_prot_update(pte) do { } while (0) #endif +#ifndef __HAVE_ARCH_MULTIPLE_ZERO_PAGE +#define move_pte(pte, prot, old_addr, new_addr) (pte) +#else +#define move_pte(pte, prot, old_addr, new_addr) \ +({ \ + pte_t newpte = (pte); \ + if (pte_present(pte) && pfn_valid(pte_pfn(pte)) && \ + pte_page(pte) == ZERO_PAGE(old_addr)) \ + newpte = mk_pte(ZERO_PAGE(new_addr), (prot)); \ + newpte; \ +}) +#endif + /* * When walking page tables, get the address of the next boundary, * or the end address of the range if that comes earlier. Although no diff --git a/include/asm-mips/pgtable.h b/include/asm-mips/pgtable.h index cbd1672c94cb..eaf5d9b3a0e1 100644 --- a/include/asm-mips/pgtable.h +++ b/include/asm-mips/pgtable.h @@ -68,6 +68,8 @@ extern unsigned long zero_page_mask; #define ZERO_PAGE(vaddr) \ (virt_to_page(empty_zero_page + (((unsigned long)(vaddr)) & zero_page_mask))) +#define __HAVE_ARCH_MULTIPLE_ZERO_PAGE + extern void paging_init(void); /* diff --git a/mm/mremap.c b/mm/mremap.c index a32fed454bd7..f343fc73a8bd 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -141,10 +141,10 @@ move_one_page(struct vm_area_struct *vma, unsigned long old_addr, if (dst) { pte_t pte; pte = ptep_clear_flush(vma, old_addr, src); + /* ZERO_PAGE can be dependant on virtual addr */ - if (pfn_valid(pte_pfn(pte)) && - pte_page(pte) == ZERO_PAGE(old_addr)) - pte = pte_wrprotect(mk_pte(ZERO_PAGE(new_addr), new_vma->vm_page_prot)); + pte = move_pte(pte, new_vma->vm_page_prot, + old_addr, new_addr); set_pte_at(mm, new_addr, dst, pte); } else error = -ENOMEM; |