diff options
Diffstat (limited to 'include/linux/page-flags.h')
| -rw-r--r-- | include/linux/page-flags.h | 76 |
1 files changed, 56 insertions, 20 deletions
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index e34a27727b9a..39b4494e29f1 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -69,13 +69,14 @@ */ enum pageflags { PG_locked, /* Page is locked. Don't touch. */ - PG_error, PG_referenced, PG_uptodate, PG_dirty, PG_lru, PG_active, + PG_workingset, PG_waiters, /* Page has waiters, check its waitqueue. Must be bit #7 and in the same byte as "PG_locked" */ + PG_error, PG_slab, PG_owner_priv_1, /* Owner use. If pagecache, fs may use*/ PG_arch_1, @@ -162,6 +163,14 @@ static inline int PagePoisoned(const struct page *page) return page->flags == PAGE_POISON_PATTERN; } +#ifdef CONFIG_DEBUG_VM +void page_init_poison(struct page *page, size_t size); +#else +static inline void page_init_poison(struct page *page, size_t size) +{ +} +#endif + /* * Page flags policies wrt compound pages * @@ -280,6 +289,8 @@ PAGEFLAG(Dirty, dirty, PF_HEAD) TESTSCFLAG(Dirty, dirty, PF_HEAD) PAGEFLAG(LRU, lru, PF_HEAD) __CLEARPAGEFLAG(LRU, lru, PF_HEAD) PAGEFLAG(Active, active, PF_HEAD) __CLEARPAGEFLAG(Active, active, PF_HEAD) TESTCLEARFLAG(Active, active, PF_HEAD) +PAGEFLAG(Workingset, workingset, PF_HEAD) + TESTCLEARFLAG(Workingset, workingset, PF_HEAD) __PAGEFLAG(Slab, slab, PF_NO_TAIL) __PAGEFLAG(SlobFree, slob_free, PF_NO_TAIL) PAGEFLAG(Checked, checked, PF_NO_COMPOUND) /* Used by some filesystems */ @@ -292,6 +303,7 @@ PAGEFLAG(Foreign, foreign, PF_NO_COMPOUND); PAGEFLAG(Reserved, reserved, PF_NO_COMPOUND) __CLEARPAGEFLAG(Reserved, reserved, PF_NO_COMPOUND) + __SETPAGEFLAG(Reserved, reserved, PF_NO_COMPOUND) PAGEFLAG(SwapBacked, swapbacked, PF_NO_TAIL) __CLEARPAGEFLAG(SwapBacked, swapbacked, PF_NO_TAIL) __SETPAGEFLAG(SwapBacked, swapbacked, PF_NO_TAIL) @@ -369,8 +381,13 @@ PAGEFLAG_FALSE(Uncached) PAGEFLAG(HWPoison, hwpoison, PF_ANY) TESTSCFLAG(HWPoison, hwpoison, PF_ANY) #define __PG_HWPOISON (1UL << PG_hwpoison) +extern bool set_hwpoison_free_buddy_page(struct page *page); #else PAGEFLAG_FALSE(HWPoison) +static inline bool set_hwpoison_free_buddy_page(struct page *page) +{ + return 0; +} #define __PG_HWPOISON 0 #endif @@ -642,49 +659,68 @@ PAGEFLAG_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. + * For pages that are never mapped to userspace (and aren't PageSlab), + * page_type may be used. Because it is initialised to -1, we invert the + * sense of the bit, so __SetPageFoo *clears* the bit used for PageFoo, and + * __ClearPageFoo *sets* the bit used for PageFoo. We reserve a few high and + * low bits so that an underflow or overflow of page_mapcount() won't be + * mistaken for a page type value. */ -#define PAGE_MAPCOUNT_OPS(uname, lname) \ + +#define PAGE_TYPE_BASE 0xf0000000 +/* Reserve 0x0000007f to catch underflows of page_mapcount */ +#define PAGE_MAPCOUNT_RESERVE -128 +#define PG_buddy 0x00000080 +#define PG_balloon 0x00000100 +#define PG_kmemcg 0x00000200 +#define PG_table 0x00000400 + +#define PageType(page, flag) \ + ((page->page_type & (PAGE_TYPE_BASE | flag)) == PAGE_TYPE_BASE) + +static inline int page_has_type(struct page *page) +{ + return (int)page->page_type < PAGE_MAPCOUNT_RESERVE; +} + +#define PAGE_TYPE_OPS(uname, lname) \ static __always_inline int Page##uname(struct page *page) \ { \ - return atomic_read(&page->_mapcount) == \ - PAGE_##lname##_MAPCOUNT_VALUE; \ + return PageType(page, PG_##lname); \ } \ 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); \ + VM_BUG_ON_PAGE(!PageType(page, 0), page); \ + page->page_type &= ~PG_##lname; \ } \ static __always_inline void __ClearPage##uname(struct page *page) \ { \ VM_BUG_ON_PAGE(!Page##uname(page), page); \ - atomic_set(&page->_mapcount, -1); \ + page->page_type |= PG_##lname; \ } /* - * PageBuddy() indicate that the page is free and in the buddy system + * PageBuddy() indicates that the page is free and in the buddy system * (see mm/page_alloc.c). */ -#define PAGE_BUDDY_MAPCOUNT_VALUE (-128) -PAGE_MAPCOUNT_OPS(Buddy, BUDDY) +PAGE_TYPE_OPS(Buddy, buddy) /* - * PageBalloon() is set on pages that are on the balloon page list + * PageBalloon() is true for pages that are on the balloon page list * (see mm/balloon_compaction.c). */ -#define PAGE_BALLOON_MAPCOUNT_VALUE (-256) -PAGE_MAPCOUNT_OPS(Balloon, BALLOON) +PAGE_TYPE_OPS(Balloon, balloon) /* * 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) +PAGE_TYPE_OPS(Kmemcg, kmemcg) + +/* + * Marks pages in use as page tables. + */ +PAGE_TYPE_OPS(Table, table) extern bool is_free_buddy_page(struct page *page); |