diff options
Diffstat (limited to 'include/linux/page-flags.h')
| -rw-r--r-- | include/linux/page-flags.h | 47 |
1 files changed, 37 insertions, 10 deletions
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index f4ed4f1b0c77..e5a32445f930 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -371,10 +371,15 @@ PAGEFLAG(Idle, idle, PF_ANY) #define PAGE_MAPPING_KSM 2 #define PAGE_MAPPING_FLAGS (PAGE_MAPPING_ANON | PAGE_MAPPING_KSM) +static __always_inline int PageAnonHead(struct page *page) +{ + return ((unsigned long)page->mapping & PAGE_MAPPING_ANON) != 0; +} + static __always_inline int PageAnon(struct page *page) { page = compound_head(page); - return ((unsigned long)page->mapping & PAGE_MAPPING_ANON) != 0; + return PageAnonHead(page); } #ifdef CONFIG_KSM @@ -474,7 +479,7 @@ static inline void ClearPageCompound(struct page *page) } #endif -#define PG_head_mask ((1L << PG_head)) +#define PG_head_mask ((1UL << PG_head)) #ifdef CONFIG_HUGETLB_PAGE int PageHuge(struct page *page); @@ -517,6 +522,27 @@ static inline int PageTransCompound(struct page *page) } /* + * PageTransCompoundMap is the same as PageTransCompound, but it also + * guarantees the primary MMU has the entire compound page mapped + * through pmd_trans_huge, which in turn guarantees the secondary MMUs + * can also map the entire compound page. This allows the secondary + * MMUs to call get_user_pages() only once for each compound page and + * to immediately map the entire compound page with a single secondary + * MMU fault. If there will be a pmd split later, the secondary MMUs + * will get an update through the MMU notifier invalidation through + * split_huge_pmd(). + * + * Unlike PageTransCompound, this is safe to be called only while + * split_huge_pmd() cannot run from under us, like if protected by the + * MMU notifier, otherwise it may result in page->_mapcount < 0 false + * positives. + */ +static inline int PageTransCompoundMap(struct page *page) +{ + return PageTransCompound(page) && atomic_read(&page->_mapcount) < 0; +} + +/* * PageTransTail returns true for both transparent huge pages * and hugetlbfs pages, so it should only be called when it's known * that hugetlbfs pages aren't involved. @@ -559,6 +585,7 @@ static inline int TestClearPageDoubleMap(struct page *page) #else TESTPAGEFLAG_FALSE(TransHuge) TESTPAGEFLAG_FALSE(TransCompound) +TESTPAGEFLAG_FALSE(TransCompoundMap) TESTPAGEFLAG_FALSE(TransTail) TESTPAGEFLAG_FALSE(DoubleMap) TESTSETFLAG_FALSE(DoubleMap) @@ -643,7 +670,7 @@ static inline void ClearPageSlabPfmemalloc(struct page *page) } #ifdef CONFIG_MMU -#define __PG_MLOCKED (1 << PG_mlocked) +#define __PG_MLOCKED (1UL << PG_mlocked) #else #define __PG_MLOCKED 0 #endif @@ -653,11 +680,11 @@ static inline void ClearPageSlabPfmemalloc(struct page *page) * these flags set. It they are, there is a problem. */ #define PAGE_FLAGS_CHECK_AT_FREE \ - (1 << PG_lru | 1 << PG_locked | \ - 1 << PG_private | 1 << PG_private_2 | \ - 1 << PG_writeback | 1 << PG_reserved | \ - 1 << PG_slab | 1 << PG_swapcache | 1 << PG_active | \ - 1 << PG_unevictable | __PG_MLOCKED) + (1UL << PG_lru | 1UL << PG_locked | \ + 1UL << PG_private | 1UL << PG_private_2 | \ + 1UL << PG_writeback | 1UL << PG_reserved | \ + 1UL << PG_slab | 1UL << PG_swapcache | 1UL << PG_active | \ + 1UL << PG_unevictable | __PG_MLOCKED) /* * Flags checked when a page is prepped for return by the page allocator. @@ -668,10 +695,10 @@ static inline void ClearPageSlabPfmemalloc(struct page *page) * alloc-free cycle to prevent from reusing the page. */ #define PAGE_FLAGS_CHECK_AT_PREP \ - (((1 << NR_PAGEFLAGS) - 1) & ~__PG_HWPOISON) + (((1UL << NR_PAGEFLAGS) - 1) & ~__PG_HWPOISON) #define PAGE_FLAGS_PRIVATE \ - (1 << PG_private | 1 << PG_private_2) + (1UL << PG_private | 1UL << PG_private_2) /** * page_has_private - Determine if page has private stuff * @page: The page to be checked |