diff options
Diffstat (limited to 'include/linux/page-flags.h')
| -rw-r--r-- | include/linux/page-flags.h | 295 |
1 files changed, 160 insertions, 135 deletions
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 2220bfec278e..f7a0e4af0c73 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -110,6 +110,7 @@ enum pageflags { PG_reclaim, /* To be reclaimed asap */ PG_swapbacked, /* Page is backed by RAM/swap */ PG_unevictable, /* Page is "unevictable" */ + PG_dropbehind, /* drop pages on IO completion */ #ifdef CONFIG_MMU PG_mlocked, /* Page is vma mlocked */ #endif @@ -166,8 +167,12 @@ enum pageflags { /* Remapped by swiotlb-xen. */ PG_xen_remapped = PG_owner_priv_1, - /* non-lru isolated movable page */ - PG_isolated = PG_reclaim, +#ifdef CONFIG_MIGRATION + /* movable_ops page that is isolated for migration */ + PG_movable_ops_isolated = PG_reclaim, + /* this is a movable_ops page (for selected typed pages only) */ + PG_movable_ops = PG_uptodate, +#endif /* Only valid for buddy pages. Used to track pages that are reported */ PG_reported = PG_uptodate, @@ -212,7 +217,7 @@ static __always_inline const struct page *page_fixed_fake_head(const struct page * cold cacheline in some cases. */ if (IS_ALIGNED((unsigned long)page, PAGE_SIZE) && - test_bit(PG_head, &page->flags)) { + test_bit(PG_head, &page->flags.f)) { /* * We can safely access the field of the @page[1] with PG_head * because the @page is a compound page composed with at least @@ -225,11 +230,48 @@ static __always_inline const struct page *page_fixed_fake_head(const struct page } return page; } + +static __always_inline bool page_count_writable(const struct page *page, int u) +{ + if (!static_branch_unlikely(&hugetlb_optimize_vmemmap_key)) + return true; + + /* + * The refcount check is ordered before the fake-head check to prevent + * the following race: + * CPU 1 (HVO) CPU 2 (speculative PFN walker) + * + * page_ref_freeze() + * synchronize_rcu() + * rcu_read_lock() + * page_is_fake_head() is false + * vmemmap_remap_pte() + * XXX: struct page[] becomes r/o + * + * page_ref_unfreeze() + * page_ref_count() is not zero + * + * atomic_add_unless(&page->_refcount) + * XXX: try to modify r/o struct page[] + * + * The refcount check also prevents modification attempts to other (r/o) + * tail pages that are not fake heads. + */ + if (atomic_read_acquire(&page->_refcount) == u) + return false; + + return page_fixed_fake_head(page) == page; +} #else static inline const struct page *page_fixed_fake_head(const struct page *page) { return page; } + +static inline bool page_count_writable(const struct page *page, int u) +{ + return true; +} #endif static __always_inline int page_is_fake_head(const struct page *page) @@ -274,7 +316,7 @@ static __always_inline unsigned long _compound_head(const struct page *page) * check that the page number lies within @folio; the caller is presumed * to have a reference to the page. */ -#define folio_page(folio, n) nth_page(&(folio)->page, n) +#define folio_page(folio, n) (&(folio)->page + (n)) static __always_inline int PageTail(const struct page *page) { @@ -283,14 +325,14 @@ static __always_inline int PageTail(const struct page *page) static __always_inline int PageCompound(const struct page *page) { - return test_bit(PG_head, &page->flags) || + return test_bit(PG_head, &page->flags.f) || READ_ONCE(page->compound_head) & 1; } #define PAGE_POISON_PATTERN -1l static inline int PagePoisoned(const struct page *page) { - return READ_ONCE(page->flags) == PAGE_POISON_PATTERN; + return READ_ONCE(page->flags.f) == PAGE_POISON_PATTERN; } #ifdef CONFIG_DEBUG_VM @@ -306,18 +348,18 @@ static const unsigned long *const_folio_flags(const struct folio *folio, { const struct page *page = &folio->page; - VM_BUG_ON_PGFLAGS(PageTail(page), page); - VM_BUG_ON_PGFLAGS(n > 0 && !test_bit(PG_head, &page->flags), page); - return &page[n].flags; + VM_BUG_ON_PGFLAGS(page->compound_head & 1, page); + VM_BUG_ON_PGFLAGS(n > 0 && !test_bit(PG_head, &page->flags.f), page); + return &page[n].flags.f; } static unsigned long *folio_flags(struct folio *folio, unsigned n) { struct page *page = &folio->page; - VM_BUG_ON_PGFLAGS(PageTail(page), page); - VM_BUG_ON_PGFLAGS(n > 0 && !test_bit(PG_head, &page->flags), page); - return &page[n].flags; + VM_BUG_ON_PGFLAGS(page->compound_head & 1, page); + VM_BUG_ON_PGFLAGS(n > 0 && !test_bit(PG_head, &page->flags.f), page); + return &page[n].flags.f; } /* @@ -407,37 +449,37 @@ FOLIO_CLEAR_FLAG(name, page) #define TESTPAGEFLAG(uname, lname, policy) \ FOLIO_TEST_FLAG(lname, FOLIO_##policy) \ static __always_inline int Page##uname(const struct page *page) \ -{ return test_bit(PG_##lname, &policy(page, 0)->flags); } +{ return test_bit(PG_##lname, &policy(page, 0)->flags.f); } #define SETPAGEFLAG(uname, lname, policy) \ FOLIO_SET_FLAG(lname, FOLIO_##policy) \ static __always_inline void SetPage##uname(struct page *page) \ -{ set_bit(PG_##lname, &policy(page, 1)->flags); } +{ set_bit(PG_##lname, &policy(page, 1)->flags.f); } #define CLEARPAGEFLAG(uname, lname, policy) \ FOLIO_CLEAR_FLAG(lname, FOLIO_##policy) \ static __always_inline void ClearPage##uname(struct page *page) \ -{ clear_bit(PG_##lname, &policy(page, 1)->flags); } +{ clear_bit(PG_##lname, &policy(page, 1)->flags.f); } #define __SETPAGEFLAG(uname, lname, policy) \ __FOLIO_SET_FLAG(lname, FOLIO_##policy) \ static __always_inline void __SetPage##uname(struct page *page) \ -{ __set_bit(PG_##lname, &policy(page, 1)->flags); } +{ __set_bit(PG_##lname, &policy(page, 1)->flags.f); } #define __CLEARPAGEFLAG(uname, lname, policy) \ __FOLIO_CLEAR_FLAG(lname, FOLIO_##policy) \ static __always_inline void __ClearPage##uname(struct page *page) \ -{ __clear_bit(PG_##lname, &policy(page, 1)->flags); } +{ __clear_bit(PG_##lname, &policy(page, 1)->flags.f); } #define TESTSETFLAG(uname, lname, policy) \ FOLIO_TEST_SET_FLAG(lname, FOLIO_##policy) \ static __always_inline int TestSetPage##uname(struct page *page) \ -{ return test_and_set_bit(PG_##lname, &policy(page, 1)->flags); } +{ return test_and_set_bit(PG_##lname, &policy(page, 1)->flags.f); } #define TESTCLEARFLAG(uname, lname, policy) \ FOLIO_TEST_CLEAR_FLAG(lname, FOLIO_##policy) \ static __always_inline int TestClearPage##uname(struct page *page) \ -{ return test_and_clear_bit(PG_##lname, &policy(page, 1)->flags); } +{ return test_and_clear_bit(PG_##lname, &policy(page, 1)->flags.f); } #define PAGEFLAG(uname, lname, policy) \ TESTPAGEFLAG(uname, lname, policy) \ @@ -562,6 +604,10 @@ PAGEFLAG(Reclaim, reclaim, PF_NO_TAIL) FOLIO_FLAG(readahead, FOLIO_HEAD_PAGE) FOLIO_TEST_CLEAR_FLAG(readahead, FOLIO_HEAD_PAGE) +FOLIO_FLAG(dropbehind, FOLIO_HEAD_PAGE) + FOLIO_TEST_CLEAR_FLAG(dropbehind, FOLIO_HEAD_PAGE) + __FOLIO_SET_FLAG(dropbehind, FOLIO_HEAD_PAGE) + #ifdef CONFIG_HIGHMEM /* * Must use a macro here due to header dependency issues. page_zone() is not @@ -572,6 +618,14 @@ FOLIO_FLAG(readahead, FOLIO_HEAD_PAGE) #else PAGEFLAG_FALSE(HighMem, highmem) #endif +#define PhysHighMem(__p) (PageHighMem(phys_to_page(__p))) + +/* Does kmap_local_folio() only allow access to one page of the folio? */ +#ifdef CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP +#define folio_test_partial_kmap(f) true +#else +#define folio_test_partial_kmap(f) folio_test_highmem(f) +#endif #ifdef CONFIG_SWAP static __always_inline bool folio_test_swapcache(const struct folio *folio) @@ -642,15 +696,12 @@ PAGEFLAG_FALSE(VmemmapSelfHosted, vmemmap_self_hosted) /* * On an anonymous folio mapped into a user virtual memory area, * folio->mapping points to its anon_vma, not to a struct address_space; - * with the PAGE_MAPPING_ANON bit set to distinguish it. See rmap.h. + * with the FOLIO_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_MOVABLE bit may be set along with the PAGE_MAPPING_ANON + * On an anonymous folio in a VM_MERGEABLE area, if CONFIG_KSM is enabled, + * the FOLIO_MAPPING_ANON_KSM bit may be set along with the FOLIO_MAPPING_ANON * bit; and then folio->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 used for non-lru movable - * page and then folio->mapping points to a struct movable_operations. + * structure which KSM associates with that merged folio. See ksm.h. * * Please note that, confusingly, "folio_mapping" refers to the inode * address_space which maps the folio from disk; whereas "folio_mapped" @@ -663,56 +714,27 @@ PAGEFLAG_FALSE(VmemmapSelfHosted, vmemmap_self_hosted) * false before calling the following functions (e.g., folio_test_anon). * See mm/slab.h. */ -#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) - -/* - * Different with flags above, this flag is used only for fsdax mode. It - * indicates that this page->mapping is now under reflink case. - */ -#define PAGE_MAPPING_DAX_SHARED ((void *)0x1) - -static __always_inline bool folio_mapping_flags(const struct folio *folio) -{ - return ((unsigned long)folio->mapping & PAGE_MAPPING_FLAGS) != 0; -} - -static __always_inline bool PageMappingFlags(const struct page *page) -{ - return ((unsigned long)page->mapping & PAGE_MAPPING_FLAGS) != 0; -} +#define FOLIO_MAPPING_ANON 0x1 +#define FOLIO_MAPPING_ANON_KSM 0x2 +#define FOLIO_MAPPING_KSM (FOLIO_MAPPING_ANON | FOLIO_MAPPING_ANON_KSM) +#define FOLIO_MAPPING_FLAGS (FOLIO_MAPPING_ANON | FOLIO_MAPPING_ANON_KSM) static __always_inline bool folio_test_anon(const struct folio *folio) { - return ((unsigned long)folio->mapping & PAGE_MAPPING_ANON) != 0; + return ((unsigned long)folio->mapping & FOLIO_MAPPING_ANON) != 0; } static __always_inline bool PageAnonNotKsm(const struct page *page) { unsigned long flags = (unsigned long)page_folio(page)->mapping; - return (flags & PAGE_MAPPING_FLAGS) == PAGE_MAPPING_ANON; + return (flags & FOLIO_MAPPING_FLAGS) == FOLIO_MAPPING_ANON; } static __always_inline bool PageAnon(const struct page *page) { return folio_test_anon(page_folio(page)); } - -static __always_inline bool __folio_test_movable(const struct folio *folio) -{ - return ((unsigned long)folio->mapping & PAGE_MAPPING_FLAGS) == - PAGE_MAPPING_MOVABLE; -} - -static __always_inline bool __PageMovable(const 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" @@ -722,8 +744,8 @@ static __always_inline bool __PageMovable(const struct page *page) */ static __always_inline bool folio_test_ksm(const struct folio *folio) { - return ((unsigned long)folio->mapping & PAGE_MAPPING_FLAGS) == - PAGE_MAPPING_KSM; + return ((unsigned long)folio->mapping & FOLIO_MAPPING_FLAGS) == + FOLIO_MAPPING_KSM; } #else FOLIO_TEST_FLAG_FALSE(ksm) @@ -816,8 +838,6 @@ void set_page_writeback(struct page *page); #define folio_start_writeback(folio) \ __folio_start_writeback(folio, false) -#define folio_start_writeback_keepwrite(folio) \ - __folio_start_writeback(folio, true) static __always_inline bool folio_test_head(const struct folio *folio) { @@ -827,7 +847,7 @@ static __always_inline bool folio_test_head(const struct folio *folio) static __always_inline int PageHead(const struct page *page) { PF_POISONED_CHECK(page); - return test_bit(PG_head, &page->flags) && !page_is_fake_head(page); + return test_bit(PG_head, &page->flags.f) && !page_is_fake_head(page); } __SETPAGEFLAG(Head, head, PF_ANY) @@ -862,38 +882,16 @@ static inline void ClearPageCompound(struct page *page) ClearPageHead(page); } FOLIO_FLAG(large_rmappable, FOLIO_SECOND_PAGE) -FOLIO_TEST_FLAG(partially_mapped, FOLIO_SECOND_PAGE) -/* - * PG_partially_mapped is protected by deferred_split split_queue_lock, - * so its safe to use non-atomic set/clear. - */ -__FOLIO_SET_FLAG(partially_mapped, FOLIO_SECOND_PAGE) -__FOLIO_CLEAR_FLAG(partially_mapped, FOLIO_SECOND_PAGE) +FOLIO_FLAG(partially_mapped, FOLIO_SECOND_PAGE) #else FOLIO_FLAG_FALSE(large_rmappable) -FOLIO_TEST_FLAG_FALSE(partially_mapped) -__FOLIO_SET_FLAG_NOOP(partially_mapped) -__FOLIO_CLEAR_FLAG_NOOP(partially_mapped) +FOLIO_FLAG_FALSE(partially_mapped) #endif #define PG_head_mask ((1UL << PG_head)) #ifdef CONFIG_TRANSPARENT_HUGEPAGE /* - * PageHuge() only returns true for hugetlbfs pages, but not for - * normal or transparent huge pages. - * - * PageTransHuge() returns true for both transparent huge and - * hugetlbfs pages, but not normal pages. PageTransHuge() can only be - * called only in the core VM paths where hugetlbfs pages can't exist. - */ -static inline int PageTransHuge(const struct page *page) -{ - VM_BUG_ON_PAGE(PageTail(page), page); - return PageHead(page); -} - -/* * PageTransCompound 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. @@ -902,21 +900,8 @@ static inline int PageTransCompound(const struct page *page) { return PageCompound(page); } - -/* - * 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. - */ -static inline int PageTransTail(const struct page *page) -{ - return PageTail(page); -} #else -TESTPAGEFLAG_FALSE(TransHuge, transhuge) TESTPAGEFLAG_FALSE(TransCompound, transcompound) -TESTPAGEFLAG_FALSE(TransCompoundMap, transcompoundmap) -TESTPAGEFLAG_FALSE(TransTail, transtail) #endif #if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_TRANSPARENT_HUGEPAGE) @@ -926,11 +911,9 @@ TESTPAGEFLAG_FALSE(TransTail, transtail) * * This flag is set by hwpoison handler. Cleared by THP split or free page. */ -PAGEFLAG(HasHWPoisoned, has_hwpoisoned, PF_SECOND) - TESTSCFLAG(HasHWPoisoned, has_hwpoisoned, PF_SECOND) +FOLIO_FLAG(has_hwpoisoned, FOLIO_SECOND_PAGE) #else -PAGEFLAG_FALSE(HasHWPoisoned, has_hwpoisoned) - TESTSCFLAG_FALSE(HasHWPoisoned, has_hwpoisoned) +FOLIO_FLAG_FALSE(has_hwpoisoned) #endif /* @@ -942,14 +925,15 @@ PAGEFLAG_FALSE(HasHWPoisoned, has_hwpoisoned) enum pagetype { /* 0x00-0x7f are positive numbers, ie mapcount */ /* Reserve 0x80-0xef for mapcount overflow. */ - PGTY_buddy = 0xf0, - PGTY_offline = 0xf1, - PGTY_table = 0xf2, - PGTY_guard = 0xf3, - PGTY_hugetlb = 0xf4, - PGTY_slab = 0xf5, - PGTY_zsmalloc = 0xf6, - PGTY_unaccepted = 0xf7, + PGTY_buddy = 0xf0, + PGTY_offline = 0xf1, + PGTY_table = 0xf2, + PGTY_guard = 0xf3, + PGTY_hugetlb = 0xf4, + PGTY_slab = 0xf5, + PGTY_zsmalloc = 0xf6, + PGTY_unaccepted = 0xf7, + PGTY_large_kmalloc = 0xf8, PGTY_mapcount_underflow = 0xff }; @@ -967,7 +951,7 @@ static inline bool page_mapcount_is_type(unsigned int mapcount) static inline bool page_has_type(const struct page *page) { - return page_mapcount_is_type(data_race(page->page_type)); + return page_type_has_type(data_race(page->page_type)); } #define FOLIO_TYPE_OPS(lname, fname) \ @@ -1064,19 +1048,7 @@ PAGE_TYPE_OPS(Table, table, pgtable) */ PAGE_TYPE_OPS(Guard, guard, guard) -FOLIO_TYPE_OPS(slab, slab) - -/** - * PageSlab - Determine if the page belongs to the slab allocator - * @page: The page to test. - * - * Context: Any context. - * Return: True for slab pages, false for any other kind of page. - */ -static inline bool PageSlab(const struct page *page) -{ - return folio_test_slab(page_folio(page)); -} +PAGE_TYPE_OPS(Slab, slab, slab) #ifdef CONFIG_HUGETLB_PAGE FOLIO_TYPE_OPS(hugetlb, hugetlb) @@ -1092,6 +1064,7 @@ PAGE_TYPE_OPS(Zsmalloc, zsmalloc, zsmalloc) * Serialized with zone lock. */ PAGE_TYPE_OPS(Unaccepted, unaccepted, unaccepted) +PAGE_TYPE_OPS(LargeKmalloc, large_kmalloc, large_kmalloc) /** * PageHuge - Determine if the page belongs to hugetlbfs @@ -1121,9 +1094,61 @@ static inline bool is_page_hwpoison(const struct page *page) return folio_test_hugetlb(folio) && PageHWPoison(&folio->page); } +static inline bool folio_contain_hwpoisoned_page(struct folio *folio) +{ + return folio_test_hwpoison(folio) || + (folio_test_large(folio) && folio_test_has_hwpoisoned(folio)); +} + bool is_free_buddy_page(const struct page *page); -PAGEFLAG(Isolated, isolated, PF_ANY); +#ifdef CONFIG_MIGRATION +/* + * This page is migratable through movable_ops (for selected typed pages + * only). + * + * Page migration of such pages might fail, for example, if the page is + * already isolated by somebody else, or if the page is about to get freed. + * + * While a subsystem might set selected typed pages that support page migration + * as being movable through movable_ops, it must never clear this flag. + * + * This flag is only cleared when the page is freed back to the buddy. + * + * Only selected page types support this flag (see page_movable_ops()) and + * the flag might be used in other context for other pages. Always use + * page_has_movable_ops() instead. + */ +TESTPAGEFLAG(MovableOps, movable_ops, PF_NO_TAIL); +SETPAGEFLAG(MovableOps, movable_ops, PF_NO_TAIL); +/* + * A movable_ops page has this flag set while it is isolated for migration. + * This flag primarily protects against concurrent migration attempts. + * + * Once migration ended (success or failure), the flag is cleared. The + * flag is managed by the migration core. + */ +PAGEFLAG(MovableOpsIsolated, movable_ops_isolated, PF_NO_TAIL); +#else /* !CONFIG_MIGRATION */ +TESTPAGEFLAG_FALSE(MovableOps, movable_ops); +SETPAGEFLAG_NOOP(MovableOps, movable_ops); +PAGEFLAG_FALSE(MovableOpsIsolated, movable_ops_isolated); +#endif /* CONFIG_MIGRATION */ + +/** + * page_has_movable_ops - test for a movable_ops page + * @page: The page to test. + * + * Test whether this is a movable_ops page. Such pages will stay that + * way until freed. + * + * Returns true if this is a movable_ops page, otherwise false. + */ +static inline bool page_has_movable_ops(const struct page *page) +{ + return PageMovableOps(page) && + (PageOffline(page) || PageZsmalloc(page)); +} static __always_inline int PageAnonExclusive(const struct page *page) { @@ -1134,28 +1159,28 @@ static __always_inline int PageAnonExclusive(const struct page *page) */ if (PageHuge(page)) page = compound_head(page); - return test_bit(PG_anon_exclusive, &PF_ANY(page, 1)->flags); + return test_bit(PG_anon_exclusive, &PF_ANY(page, 1)->flags.f); } static __always_inline void SetPageAnonExclusive(struct page *page) { VM_BUG_ON_PGFLAGS(!PageAnonNotKsm(page), page); VM_BUG_ON_PGFLAGS(PageHuge(page) && !PageHead(page), page); - set_bit(PG_anon_exclusive, &PF_ANY(page, 1)->flags); + set_bit(PG_anon_exclusive, &PF_ANY(page, 1)->flags.f); } static __always_inline void ClearPageAnonExclusive(struct page *page) { VM_BUG_ON_PGFLAGS(!PageAnonNotKsm(page), page); VM_BUG_ON_PGFLAGS(PageHuge(page) && !PageHead(page), page); - clear_bit(PG_anon_exclusive, &PF_ANY(page, 1)->flags); + clear_bit(PG_anon_exclusive, &PF_ANY(page, 1)->flags.f); } static __always_inline void __ClearPageAnonExclusive(struct page *page) { VM_BUG_ON_PGFLAGS(!PageAnon(page), page); VM_BUG_ON_PGFLAGS(PageHuge(page) && !PageHead(page), page); - __clear_bit(PG_anon_exclusive, &PF_ANY(page, 1)->flags); + __clear_bit(PG_anon_exclusive, &PF_ANY(page, 1)->flags.f); } #ifdef CONFIG_MMU @@ -1205,7 +1230,7 @@ static __always_inline void __ClearPageAnonExclusive(struct page *page) */ static inline int folio_has_private(const struct folio *folio) { - return !!(folio->flags & PAGE_FLAGS_PRIVATE); + return !!(folio->flags.f & PAGE_FLAGS_PRIVATE); } #undef PF_ANY |