diff options
Diffstat (limited to 'include/asm-generic/pgtable.h')
-rw-r--r-- | include/asm-generic/pgtable.h | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h index 701beab27aab..f50a87d35239 100644 --- a/include/asm-generic/pgtable.h +++ b/include/asm-generic/pgtable.h @@ -7,6 +7,16 @@ #include <linux/mm_types.h> #include <linux/bug.h> +/* + * On almost all architectures and configurations, 0 can be used as the + * upper ceiling to free_pgtables(): on many architectures it has the same + * effect as using TASK_SIZE. However, there is one configuration which + * must impose a more careful limit, to avoid freeing kernel pgtables. + */ +#ifndef USER_PGTABLES_CEILING +#define USER_PGTABLES_CEILING 0UL +#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, @@ -461,10 +471,8 @@ static inline int is_zero_pfn(unsigned long pfn) return offset_from_zero_pfn <= (zero_page_mask >> PAGE_SHIFT); } -static inline unsigned long my_zero_pfn(unsigned long addr) -{ - return page_to_pfn(ZERO_PAGE(addr)); -} +#define my_zero_pfn(addr) page_to_pfn(ZERO_PAGE(addr)) + #else static inline int is_zero_pfn(unsigned long pfn) { |