diff options
Diffstat (limited to 'include/linux/page-flags.h')
| -rw-r--r-- | include/linux/page-flags.h | 167 |
1 files changed, 108 insertions, 59 deletions
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index f4ed4f1b0c77..74e4dda91238 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -129,6 +129,9 @@ enum pageflags { /* Compound pages. Stored in first tail page's flags */ PG_double_map = PG_private_2, + + /* non-lru isolated movable page */ + PG_isolated = PG_reclaim, }; #ifndef __GENERATING_BOUNDS_H @@ -292,11 +295,11 @@ PAGEFLAG(OwnerPriv1, owner_priv_1, PF_ANY) */ TESTPAGEFLAG(Writeback, writeback, PF_NO_COMPOUND) TESTSCFLAG(Writeback, writeback, PF_NO_COMPOUND) -PAGEFLAG(MappedToDisk, mappedtodisk, PF_NO_COMPOUND) +PAGEFLAG(MappedToDisk, mappedtodisk, PF_NO_TAIL) /* PG_readahead is only used for reads; PG_reclaim is only for writes */ -PAGEFLAG(Reclaim, reclaim, PF_NO_COMPOUND) - TESTCLEARFLAG(Reclaim, reclaim, PF_NO_COMPOUND) +PAGEFLAG(Reclaim, reclaim, PF_NO_TAIL) + TESTCLEARFLAG(Reclaim, reclaim, PF_NO_TAIL) PAGEFLAG(Readahead, reclaim, PF_NO_COMPOUND) TESTCLEARFLAG(Readahead, reclaim, PF_NO_COMPOUND) @@ -357,19 +360,26 @@ PAGEFLAG(Idle, idle, PF_ANY) * with the PAGE_MAPPING_ANON bit set to distinguish it. See rmap.h. * * On an anonymous page in a VM_MERGEABLE area, if CONFIG_KSM is enabled, - * the PAGE_MAPPING_KSM bit may be set along with the PAGE_MAPPING_ANON bit; - * and then page->mapping points, not to an anon_vma, but to a private + * the PAGE_MAPPING_MOVABLE bit may be set along with the PAGE_MAPPING_ANON + * bit; and then page->mapping points, not to an anon_vma, but to a private * structure which KSM associates with that merged page. See ksm.h. * - * PAGE_MAPPING_KSM without PAGE_MAPPING_ANON is currently never used. + * PAGE_MAPPING_KSM without PAGE_MAPPING_ANON is used for non-lru movable + * page and then page->mapping points a struct address_space. * * Please note that, confusingly, "page_mapping" refers to the inode * address_space which maps the page from disk; whereas "page_mapped" * refers to user virtual address space into which the page is mapped. */ -#define PAGE_MAPPING_ANON 1 -#define PAGE_MAPPING_KSM 2 -#define PAGE_MAPPING_FLAGS (PAGE_MAPPING_ANON | PAGE_MAPPING_KSM) +#define PAGE_MAPPING_ANON 0x1 +#define PAGE_MAPPING_MOVABLE 0x2 +#define PAGE_MAPPING_KSM (PAGE_MAPPING_ANON | PAGE_MAPPING_MOVABLE) +#define PAGE_MAPPING_FLAGS (PAGE_MAPPING_ANON | PAGE_MAPPING_MOVABLE) + +static __always_inline int PageMappingFlags(struct page *page) +{ + return ((unsigned long)page->mapping & PAGE_MAPPING_FLAGS) != 0; +} static __always_inline int PageAnon(struct page *page) { @@ -377,6 +387,12 @@ static __always_inline int PageAnon(struct page *page) return ((unsigned long)page->mapping & PAGE_MAPPING_ANON) != 0; } +static __always_inline int __PageMovable(struct page *page) +{ + return ((unsigned long)page->mapping & PAGE_MAPPING_FLAGS) == + PAGE_MAPPING_MOVABLE; +} + #ifdef CONFIG_KSM /* * A KSM page is one of those write-protected "shared pages" or "merged pages" @@ -388,7 +404,7 @@ static __always_inline int PageKsm(struct page *page) { page = compound_head(page); return ((unsigned long)page->mapping & PAGE_MAPPING_FLAGS) == - (PAGE_MAPPING_ANON | PAGE_MAPPING_KSM); + PAGE_MAPPING_KSM; } #else TESTPAGEFLAG_FALSE(Ksm) @@ -474,7 +490,7 @@ 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 +533,27 @@ 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. @@ -544,6 +581,17 @@ static inline int PageDoubleMap(struct page *page) return PageHead(page) && test_bit(PG_double_map, &page[1].flags); } +static inline void SetPageDoubleMap(struct page *page) +{ + VM_BUG_ON_PAGE(!PageHead(page), page); + set_bit(PG_double_map, &page[1].flags); +} + +static inline void ClearPageDoubleMap(struct page *page) +{ + VM_BUG_ON_PAGE(!PageHead(page), page); + clear_bit(PG_double_map, &page[1].flags); +} static inline int TestSetPageDoubleMap(struct page *page) { VM_BUG_ON_PAGE(!PageHead(page), page); @@ -559,60 +607,61 @@ static inline int TestClearPageDoubleMap(struct page *page) #else TESTPAGEFLAG_FALSE(TransHuge) TESTPAGEFLAG_FALSE(TransCompound) +TESTPAGEFLAG_FALSE(TransCompoundMap) TESTPAGEFLAG_FALSE(TransTail) -TESTPAGEFLAG_FALSE(DoubleMap) +PAGEFLAG_FALSE(DoubleMap) TESTSETFLAG_FALSE(DoubleMap) TESTCLEARFLAG_FALSE(DoubleMap) #endif /* + * For pages that are never mapped to userspace, page->mapcount may be + * used for storing extra information about page type. Any value used + * for this purpose must be <= -2, but it's better start not too close + * to -2 so that an underflow of the page_mapcount() won't be mistaken + * for a special page. + */ +#define PAGE_MAPCOUNT_OPS(uname, lname) \ +static __always_inline int Page##uname(struct page *page) \ +{ \ + return atomic_read(&page->_mapcount) == \ + PAGE_##lname##_MAPCOUNT_VALUE; \ +} \ +static __always_inline void __SetPage##uname(struct page *page) \ +{ \ + VM_BUG_ON_PAGE(atomic_read(&page->_mapcount) != -1, page); \ + atomic_set(&page->_mapcount, PAGE_##lname##_MAPCOUNT_VALUE); \ +} \ +static __always_inline void __ClearPage##uname(struct page *page) \ +{ \ + VM_BUG_ON_PAGE(!Page##uname(page), page); \ + atomic_set(&page->_mapcount, -1); \ +} + +/* * PageBuddy() indicate that the page is free and in the buddy system * (see mm/page_alloc.c). - * - * PAGE_BUDDY_MAPCOUNT_VALUE must be <= -2 but better not too close to - * -2 so that an underflow of the page_mapcount() won't be mistaken - * for a genuine PAGE_BUDDY_MAPCOUNT_VALUE. -128 can be created very - * efficiently by most CPU architectures. */ -#define PAGE_BUDDY_MAPCOUNT_VALUE (-128) - -static inline int PageBuddy(struct page *page) -{ - return atomic_read(&page->_mapcount) == PAGE_BUDDY_MAPCOUNT_VALUE; -} +#define PAGE_BUDDY_MAPCOUNT_VALUE (-128) +PAGE_MAPCOUNT_OPS(Buddy, BUDDY) -static inline void __SetPageBuddy(struct page *page) -{ - VM_BUG_ON_PAGE(atomic_read(&page->_mapcount) != -1, page); - atomic_set(&page->_mapcount, PAGE_BUDDY_MAPCOUNT_VALUE); -} +/* + * PageBalloon() is set on pages that are on the balloon page list + * (see mm/balloon_compaction.c). + */ +#define PAGE_BALLOON_MAPCOUNT_VALUE (-256) +PAGE_MAPCOUNT_OPS(Balloon, BALLOON) -static inline void __ClearPageBuddy(struct page *page) -{ - VM_BUG_ON_PAGE(!PageBuddy(page), page); - atomic_set(&page->_mapcount, -1); -} +/* + * If kmemcg is enabled, the buddy allocator will set PageKmemcg() on + * pages allocated with __GFP_ACCOUNT. It gets cleared on page free. + */ +#define PAGE_KMEMCG_MAPCOUNT_VALUE (-512) +PAGE_MAPCOUNT_OPS(Kmemcg, KMEMCG) extern bool is_free_buddy_page(struct page *page); -#define PAGE_BALLOON_MAPCOUNT_VALUE (-256) - -static inline int PageBalloon(struct page *page) -{ - return atomic_read(&page->_mapcount) == PAGE_BALLOON_MAPCOUNT_VALUE; -} - -static inline void __SetPageBalloon(struct page *page) -{ - VM_BUG_ON_PAGE(atomic_read(&page->_mapcount) != -1, page); - atomic_set(&page->_mapcount, PAGE_BALLOON_MAPCOUNT_VALUE); -} - -static inline void __ClearPageBalloon(struct page *page) -{ - VM_BUG_ON_PAGE(!PageBalloon(page), page); - atomic_set(&page->_mapcount, -1); -} +__PAGEFLAG(Isolated, isolated, PF_ANY); /* * If network-based swap is enabled, sl*b must keep track of whether pages @@ -643,7 +692,7 @@ 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 +702,11 @@ 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 +717,10 @@ 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 |