1083 lines
35 KiB
C
1083 lines
35 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
/*
|
|
* Macros for manipulating and testing page->flags
|
|
*/
|
|
|
|
#ifndef PAGE_FLAGS_H
|
|
#define PAGE_FLAGS_H
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/bug.h>
|
|
#include <linux/mmdebug.h>
|
|
#ifndef __GENERATING_BOUNDS_H
|
|
#include <linux/mm_types.h>
|
|
#include <generated/bounds.h>
|
|
#endif /* !__GENERATING_BOUNDS_H */
|
|
|
|
/*
|
|
* Various page->flags bits:
|
|
*
|
|
* PG_reserved is set for special pages. The "struct page" of such a page
|
|
* should in general not be touched (e.g. set dirty) except by its owner.
|
|
* Pages marked as PG_reserved include:
|
|
* - Pages part of the kernel image (including vDSO) and similar (e.g. BIOS,
|
|
* initrd, HW tables)
|
|
* - Pages reserved or allocated early during boot (before the page allocator
|
|
* was initialized). This includes (depending on the architecture) the
|
|
* initial vmemmap, initial page tables, crashkernel, elfcorehdr, and much
|
|
* much more. Once (if ever) freed, PG_reserved is cleared and they will
|
|
* be given to the page allocator.
|
|
* - Pages falling into physical memory gaps - not IORESOURCE_SYSRAM. Trying
|
|
* to read/write these pages might end badly. Don't touch!
|
|
* - The zero page(s)
|
|
* - Pages not added to the page allocator when onlining a section because
|
|
* they were excluded via the online_page_callback() or because they are
|
|
* PG_hwpoison.
|
|
* - Pages allocated in the context of kexec/kdump (loaded kernel image,
|
|
* control pages, vmcoreinfo)
|
|
* - MMIO/DMA pages. Some architectures don't allow to ioremap pages that are
|
|
* not marked PG_reserved (as they might be in use by somebody else who does
|
|
* not respect the caching strategy).
|
|
* - Pages part of an offline section (struct pages of offline sections should
|
|
* not be trusted as they will be initialized when first onlined).
|
|
* - MCA pages on ia64
|
|
* - Pages holding CPU notes for POWER Firmware Assisted Dump
|
|
* - Device memory (e.g. PMEM, DAX, HMM)
|
|
* Some PG_reserved pages will be excluded from the hibernation image.
|
|
* PG_reserved does in general not hinder anybody from dumping or swapping
|
|
* and is no longer required for remap_pfn_range(). ioremap might require it.
|
|
* Consequently, PG_reserved for a page mapped into user space can indicate
|
|
* the zero page, the vDSO, MMIO pages or device memory.
|
|
*
|
|
* The PG_private bitflag is set on pagecache pages if they contain filesystem
|
|
* specific data (which is normally at page->private). It can be used by
|
|
* private allocations for its own usage.
|
|
*
|
|
* During initiation of disk I/O, PG_locked is set. This bit is set before I/O
|
|
* and cleared when writeback _starts_ or when read _completes_. PG_writeback
|
|
* is set before writeback starts and cleared when it finishes.
|
|
*
|
|
* PG_locked also pins a page in pagecache, and blocks truncation of the file
|
|
* while it is held.
|
|
*
|
|
* page_waitqueue(page) is a wait queue of all tasks waiting for the page
|
|
* to become unlocked.
|
|
*
|
|
* PG_swapbacked is set when a page uses swap as a backing storage. This are
|
|
* usually PageAnon or shmem pages but please note that even anonymous pages
|
|
* might lose their PG_swapbacked flag when they simply can be dropped (e.g. as
|
|
* a result of MADV_FREE).
|
|
*
|
|
* PG_referenced, PG_reclaim are used for page reclaim for anonymous and
|
|
* file-backed pagecache (see mm/vmscan.c).
|
|
*
|
|
* PG_error is set to indicate that an I/O error occurred on this page.
|
|
*
|
|
* PG_arch_1 is an architecture specific page state bit. The generic code
|
|
* guarantees that this bit is cleared for a page when it first is entered into
|
|
* the page cache.
|
|
*
|
|
* PG_hwpoison indicates that a page got corrupted in hardware and contains
|
|
* data with incorrect ECC bits that triggered a machine check. Accessing is
|
|
* not safe since it may cause another machine check. Don't touch!
|
|
*/
|
|
|
|
/*
|
|
* Don't use the pageflags directly. Use the PageFoo macros.
|
|
*
|
|
* The page flags field is split into two parts, the main flags area
|
|
* which extends from the low bits upwards, and the fields area which
|
|
* extends from the high bits downwards.
|
|
*
|
|
* | FIELD | ... | FLAGS |
|
|
* N-1 ^ 0
|
|
* (NR_PAGEFLAGS)
|
|
*
|
|
* The fields area is reserved for fields mapping zone, node (for NUMA) and
|
|
* SPARSEMEM section (for variants of SPARSEMEM that require section ids like
|
|
* SPARSEMEM_EXTREME with !SPARSEMEM_VMEMMAP).
|
|
*/
|
|
enum pageflags {
|
|
PG_locked, /* Page is locked. Don't touch. */
|
|
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,
|
|
PG_reserved,
|
|
PG_private, /* If pagecache, has fs-private data */
|
|
PG_private_2, /* If pagecache, has fs aux data */
|
|
PG_writeback, /* Page is under writeback */
|
|
PG_head, /* A head page */
|
|
PG_mappedtodisk, /* Has blocks allocated on-disk */
|
|
PG_reclaim, /* To be reclaimed asap */
|
|
PG_swapbacked, /* Page is backed by RAM/swap */
|
|
PG_unevictable, /* Page is "unevictable" */
|
|
#ifdef CONFIG_MMU
|
|
PG_mlocked, /* Page is vma mlocked */
|
|
#endif
|
|
#ifdef CONFIG_ARCH_USES_PG_UNCACHED
|
|
PG_uncached, /* Page has been mapped as uncached */
|
|
#endif
|
|
#ifdef CONFIG_MEMORY_FAILURE
|
|
PG_hwpoison, /* hardware poisoned page. Don't touch */
|
|
#endif
|
|
#if defined(CONFIG_PAGE_IDLE_FLAG) && defined(CONFIG_64BIT)
|
|
PG_young,
|
|
PG_idle,
|
|
#endif
|
|
#ifdef CONFIG_ARCH_USES_PG_ARCH_X
|
|
PG_arch_2,
|
|
PG_arch_3,
|
|
#endif
|
|
#ifdef CONFIG_KASAN_HW_TAGS
|
|
PG_skip_kasan_poison,
|
|
#endif
|
|
__NR_PAGEFLAGS,
|
|
|
|
PG_readahead = PG_reclaim,
|
|
|
|
/*
|
|
* Depending on the way an anonymous folio can be mapped into a page
|
|
* table (e.g., single PMD/PUD/CONT of the head page vs. PTE-mapped
|
|
* THP), PG_anon_exclusive may be set only for the head page or for
|
|
* tail pages of an anonymous folio. For now, we only expect it to be
|
|
* set on tail pages for PTE-mapped THP.
|
|
*/
|
|
PG_anon_exclusive = PG_mappedtodisk,
|
|
|
|
/* Filesystems */
|
|
PG_checked = PG_owner_priv_1,
|
|
|
|
/* SwapBacked */
|
|
PG_swapcache = PG_owner_priv_1, /* Swap page: swp_entry_t in private */
|
|
|
|
/* Two page bits are conscripted by FS-Cache to maintain local caching
|
|
* state. These bits are set on pages belonging to the netfs's inodes
|
|
* when those inodes are being locally cached.
|
|
*/
|
|
PG_fscache = PG_private_2, /* page backed by cache */
|
|
|
|
/* XEN */
|
|
/* Pinned in Xen as a read-only pagetable page. */
|
|
PG_pinned = PG_owner_priv_1,
|
|
/* Pinned as part of domain save (see xen_mm_pin_all()). */
|
|
PG_savepinned = PG_dirty,
|
|
/* Has a grant mapping of another (foreign) domain's page. */
|
|
PG_foreign = PG_owner_priv_1,
|
|
/* Remapped by swiotlb-xen. */
|
|
PG_xen_remapped = PG_owner_priv_1,
|
|
|
|
/* SLOB */
|
|
PG_slob_free = PG_private,
|
|
|
|
#ifdef CONFIG_MEMORY_FAILURE
|
|
/*
|
|
* Compound pages. Stored in first tail page's flags.
|
|
* Indicates that at least one subpage is hwpoisoned in the
|
|
* THP.
|
|
*/
|
|
PG_has_hwpoisoned = PG_error,
|
|
#endif
|
|
|
|
/* non-lru isolated movable page */
|
|
PG_isolated = PG_reclaim,
|
|
|
|
/* Only valid for buddy pages. Used to track pages that are reported */
|
|
PG_reported = PG_uptodate,
|
|
|
|
#ifdef CONFIG_MEMORY_HOTPLUG
|
|
/* For self-hosted memmap pages */
|
|
PG_vmemmap_self_hosted = PG_owner_priv_1,
|
|
#endif
|
|
};
|
|
|
|
#define PAGEFLAGS_MASK ((1UL << NR_PAGEFLAGS) - 1)
|
|
|
|
#ifndef __GENERATING_BOUNDS_H
|
|
|
|
#ifdef CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP
|
|
DECLARE_STATIC_KEY_FALSE(hugetlb_optimize_vmemmap_key);
|
|
|
|
/*
|
|
* Return the real head page struct iff the @page is a fake head page, otherwise
|
|
* return the @page itself. See Documentation/mm/vmemmap_dedup.rst.
|
|
*/
|
|
static __always_inline const struct page *page_fixed_fake_head(const struct page *page)
|
|
{
|
|
if (!static_branch_unlikely(&hugetlb_optimize_vmemmap_key))
|
|
return page;
|
|
|
|
/*
|
|
* Only addresses aligned with PAGE_SIZE of struct page may be fake head
|
|
* struct page. The alignment check aims to avoid access the fields (
|
|
* e.g. compound_head) of the @page[1]. It can avoid touch a (possibly)
|
|
* cold cacheline in some cases.
|
|
*/
|
|
if (IS_ALIGNED((unsigned long)page, PAGE_SIZE) &&
|
|
test_bit(PG_head, &page->flags)) {
|
|
/*
|
|
* We can safely access the field of the @page[1] with PG_head
|
|
* because the @page is a compound page composed with at least
|
|
* two contiguous pages.
|
|
*/
|
|
unsigned long head = READ_ONCE(page[1].compound_head);
|
|
|
|
if (likely(head & 1))
|
|
return (const struct page *)(head - 1);
|
|
}
|
|
return page;
|
|
}
|
|
#else
|
|
static inline const struct page *page_fixed_fake_head(const struct page *page)
|
|
{
|
|
return page;
|
|
}
|
|
#endif
|
|
|
|
static __always_inline int page_is_fake_head(struct page *page)
|
|
{
|
|
return page_fixed_fake_head(page) != page;
|
|
}
|
|
|
|
static inline unsigned long _compound_head(const struct page *page)
|
|
{
|
|
unsigned long head = READ_ONCE(page->compound_head);
|
|
|
|
if (unlikely(head & 1))
|
|
return head - 1;
|
|
return (unsigned long)page_fixed_fake_head(page);
|
|
}
|
|
|
|
#define compound_head(page) ((typeof(page))_compound_head(page))
|
|
|
|
/**
|
|
* page_folio - Converts from page to folio.
|
|
* @p: The page.
|
|
*
|
|
* Every page is part of a folio. This function cannot be called on a
|
|
* NULL pointer.
|
|
*
|
|
* Context: No reference, nor lock is required on @page. If the caller
|
|
* does not hold a reference, this call may race with a folio split, so
|
|
* it should re-check the folio still contains this page after gaining
|
|
* a reference on the folio.
|
|
* Return: The folio which contains this page.
|
|
*/
|
|
#define page_folio(p) (_Generic((p), \
|
|
const struct page *: (const struct folio *)_compound_head(p), \
|
|
struct page *: (struct folio *)_compound_head(p)))
|
|
|
|
/**
|
|
* folio_page - Return a page from a folio.
|
|
* @folio: The folio.
|
|
* @n: The page number to return.
|
|
*
|
|
* @n is relative to the start of the folio. This function does not
|
|
* 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)
|
|
|
|
static __always_inline int PageTail(struct page *page)
|
|
{
|
|
return READ_ONCE(page->compound_head) & 1 || page_is_fake_head(page);
|
|
}
|
|
|
|
static __always_inline int PageCompound(struct page *page)
|
|
{
|
|
return test_bit(PG_head, &page->flags) ||
|
|
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;
|
|
}
|
|
|
|
#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
|
|
|
|
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;
|
|
}
|
|
|
|
/*
|
|
* Page flags policies wrt compound pages
|
|
*
|
|
* PF_POISONED_CHECK
|
|
* check if this struct page poisoned/uninitialized
|
|
*
|
|
* PF_ANY:
|
|
* the page flag is relevant for small, head and tail pages.
|
|
*
|
|
* PF_HEAD:
|
|
* for compound page all operations related to the page flag applied to
|
|
* head page.
|
|
*
|
|
* PF_ONLY_HEAD:
|
|
* for compound page, callers only ever operate on the head page.
|
|
*
|
|
* PF_NO_TAIL:
|
|
* modifications of the page flag must be done on small or head pages,
|
|
* checks can be done on tail pages too.
|
|
*
|
|
* PF_NO_COMPOUND:
|
|
* the page flag is not relevant for compound pages.
|
|
*
|
|
* PF_SECOND:
|
|
* the page flag is stored in the first tail page.
|
|
*/
|
|
#define PF_POISONED_CHECK(page) ({ \
|
|
VM_BUG_ON_PGFLAGS(PagePoisoned(page), page); \
|
|
page; })
|
|
#define PF_ANY(page, enforce) PF_POISONED_CHECK(page)
|
|
#define PF_HEAD(page, enforce) PF_POISONED_CHECK(compound_head(page))
|
|
#define PF_ONLY_HEAD(page, enforce) ({ \
|
|
VM_BUG_ON_PGFLAGS(PageTail(page), page); \
|
|
PF_POISONED_CHECK(page); })
|
|
#define PF_NO_TAIL(page, enforce) ({ \
|
|
VM_BUG_ON_PGFLAGS(enforce && PageTail(page), page); \
|
|
PF_POISONED_CHECK(compound_head(page)); })
|
|
#define PF_NO_COMPOUND(page, enforce) ({ \
|
|
VM_BUG_ON_PGFLAGS(enforce && PageCompound(page), page); \
|
|
PF_POISONED_CHECK(page); })
|
|
#define PF_SECOND(page, enforce) ({ \
|
|
VM_BUG_ON_PGFLAGS(!PageHead(page), page); \
|
|
PF_POISONED_CHECK(&page[1]); })
|
|
|
|
/* Which page is the flag stored in */
|
|
#define FOLIO_PF_ANY 0
|
|
#define FOLIO_PF_HEAD 0
|
|
#define FOLIO_PF_ONLY_HEAD 0
|
|
#define FOLIO_PF_NO_TAIL 0
|
|
#define FOLIO_PF_NO_COMPOUND 0
|
|
#define FOLIO_PF_SECOND 1
|
|
|
|
/*
|
|
* Macros to create function definitions for page flags
|
|
*/
|
|
#define TESTPAGEFLAG(uname, lname, policy) \
|
|
static __always_inline bool folio_test_##lname(struct folio *folio) \
|
|
{ return test_bit(PG_##lname, folio_flags(folio, FOLIO_##policy)); } \
|
|
static __always_inline int Page##uname(struct page *page) \
|
|
{ return test_bit(PG_##lname, &policy(page, 0)->flags); }
|
|
|
|
#define SETPAGEFLAG(uname, lname, policy) \
|
|
static __always_inline \
|
|
void folio_set_##lname(struct folio *folio) \
|
|
{ set_bit(PG_##lname, folio_flags(folio, FOLIO_##policy)); } \
|
|
static __always_inline void SetPage##uname(struct page *page) \
|
|
{ set_bit(PG_##lname, &policy(page, 1)->flags); }
|
|
|
|
#define CLEARPAGEFLAG(uname, lname, policy) \
|
|
static __always_inline \
|
|
void folio_clear_##lname(struct folio *folio) \
|
|
{ clear_bit(PG_##lname, folio_flags(folio, FOLIO_##policy)); } \
|
|
static __always_inline void ClearPage##uname(struct page *page) \
|
|
{ clear_bit(PG_##lname, &policy(page, 1)->flags); }
|
|
|
|
#define __SETPAGEFLAG(uname, lname, policy) \
|
|
static __always_inline \
|
|
void __folio_set_##lname(struct folio *folio) \
|
|
{ __set_bit(PG_##lname, folio_flags(folio, FOLIO_##policy)); } \
|
|
static __always_inline void __SetPage##uname(struct page *page) \
|
|
{ __set_bit(PG_##lname, &policy(page, 1)->flags); }
|
|
|
|
#define __CLEARPAGEFLAG(uname, lname, policy) \
|
|
static __always_inline \
|
|
void __folio_clear_##lname(struct folio *folio) \
|
|
{ __clear_bit(PG_##lname, folio_flags(folio, FOLIO_##policy)); } \
|
|
static __always_inline void __ClearPage##uname(struct page *page) \
|
|
{ __clear_bit(PG_##lname, &policy(page, 1)->flags); }
|
|
|
|
#define TESTSETFLAG(uname, lname, policy) \
|
|
static __always_inline \
|
|
bool folio_test_set_##lname(struct folio *folio) \
|
|
{ return test_and_set_bit(PG_##lname, folio_flags(folio, FOLIO_##policy)); } \
|
|
static __always_inline int TestSetPage##uname(struct page *page) \
|
|
{ return test_and_set_bit(PG_##lname, &policy(page, 1)->flags); }
|
|
|
|
#define TESTCLEARFLAG(uname, lname, policy) \
|
|
static __always_inline \
|
|
bool folio_test_clear_##lname(struct folio *folio) \
|
|
{ return test_and_clear_bit(PG_##lname, folio_flags(folio, FOLIO_##policy)); } \
|
|
static __always_inline int TestClearPage##uname(struct page *page) \
|
|
{ return test_and_clear_bit(PG_##lname, &policy(page, 1)->flags); }
|
|
|
|
#define PAGEFLAG(uname, lname, policy) \
|
|
TESTPAGEFLAG(uname, lname, policy) \
|
|
SETPAGEFLAG(uname, lname, policy) \
|
|
CLEARPAGEFLAG(uname, lname, policy)
|
|
|
|
#define __PAGEFLAG(uname, lname, policy) \
|
|
TESTPAGEFLAG(uname, lname, policy) \
|
|
__SETPAGEFLAG(uname, lname, policy) \
|
|
__CLEARPAGEFLAG(uname, lname, policy)
|
|
|
|
#define TESTSCFLAG(uname, lname, policy) \
|
|
TESTSETFLAG(uname, lname, policy) \
|
|
TESTCLEARFLAG(uname, lname, policy)
|
|
|
|
#define TESTPAGEFLAG_FALSE(uname, lname) \
|
|
static inline bool folio_test_##lname(const struct folio *folio) { return false; } \
|
|
static inline int Page##uname(const struct page *page) { return 0; }
|
|
|
|
#define SETPAGEFLAG_NOOP(uname, lname) \
|
|
static inline void folio_set_##lname(struct folio *folio) { } \
|
|
static inline void SetPage##uname(struct page *page) { }
|
|
|
|
#define CLEARPAGEFLAG_NOOP(uname, lname) \
|
|
static inline void folio_clear_##lname(struct folio *folio) { } \
|
|
static inline void ClearPage##uname(struct page *page) { }
|
|
|
|
#define __CLEARPAGEFLAG_NOOP(uname, lname) \
|
|
static inline void __folio_clear_##lname(struct folio *folio) { } \
|
|
static inline void __ClearPage##uname(struct page *page) { }
|
|
|
|
#define TESTSETFLAG_FALSE(uname, lname) \
|
|
static inline bool folio_test_set_##lname(struct folio *folio) \
|
|
{ return 0; } \
|
|
static inline int TestSetPage##uname(struct page *page) { return 0; }
|
|
|
|
#define TESTCLEARFLAG_FALSE(uname, lname) \
|
|
static inline bool folio_test_clear_##lname(struct folio *folio) \
|
|
{ return 0; } \
|
|
static inline int TestClearPage##uname(struct page *page) { return 0; }
|
|
|
|
#define PAGEFLAG_FALSE(uname, lname) TESTPAGEFLAG_FALSE(uname, lname) \
|
|
SETPAGEFLAG_NOOP(uname, lname) CLEARPAGEFLAG_NOOP(uname, lname)
|
|
|
|
#define TESTSCFLAG_FALSE(uname, lname) \
|
|
TESTSETFLAG_FALSE(uname, lname) TESTCLEARFLAG_FALSE(uname, lname)
|
|
|
|
__PAGEFLAG(Locked, locked, PF_NO_TAIL)
|
|
PAGEFLAG(Waiters, waiters, PF_ONLY_HEAD)
|
|
PAGEFLAG(Error, error, PF_NO_TAIL) TESTCLEARFLAG(Error, error, PF_NO_TAIL)
|
|
PAGEFLAG(Referenced, referenced, PF_HEAD)
|
|
TESTCLEARFLAG(Referenced, referenced, PF_HEAD)
|
|
__SETPAGEFLAG(Referenced, referenced, PF_HEAD)
|
|
PAGEFLAG(Dirty, dirty, PF_HEAD) TESTSCFLAG(Dirty, dirty, PF_HEAD)
|
|
__CLEARPAGEFLAG(Dirty, dirty, PF_HEAD)
|
|
PAGEFLAG(LRU, lru, PF_HEAD) __CLEARPAGEFLAG(LRU, lru, PF_HEAD)
|
|
TESTCLEARFLAG(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 */
|
|
|
|
/* Xen */
|
|
PAGEFLAG(Pinned, pinned, PF_NO_COMPOUND)
|
|
TESTSCFLAG(Pinned, pinned, PF_NO_COMPOUND)
|
|
PAGEFLAG(SavePinned, savepinned, PF_NO_COMPOUND);
|
|
PAGEFLAG(Foreign, foreign, PF_NO_COMPOUND);
|
|
PAGEFLAG(XenRemapped, xen_remapped, PF_NO_COMPOUND)
|
|
TESTCLEARFLAG(XenRemapped, xen_remapped, 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)
|
|
|
|
/*
|
|
* Private page markings that may be used by the filesystem that owns the page
|
|
* for its own purposes.
|
|
* - PG_private and PG_private_2 cause release_folio() and co to be invoked
|
|
*/
|
|
PAGEFLAG(Private, private, PF_ANY)
|
|
PAGEFLAG(Private2, private_2, PF_ANY) TESTSCFLAG(Private2, private_2, PF_ANY)
|
|
PAGEFLAG(OwnerPriv1, owner_priv_1, PF_ANY)
|
|
TESTCLEARFLAG(OwnerPriv1, owner_priv_1, PF_ANY)
|
|
|
|
/*
|
|
* Only test-and-set exist for PG_writeback. The unconditional operators are
|
|
* risky: they bypass page accounting.
|
|
*/
|
|
TESTPAGEFLAG(Writeback, writeback, PF_NO_TAIL)
|
|
TESTSCFLAG(Writeback, writeback, PF_NO_TAIL)
|
|
PAGEFLAG(MappedToDisk, mappedtodisk, PF_NO_TAIL)
|
|
|
|
/* PG_readahead is only used for reads; PG_reclaim is only for writes */
|
|
PAGEFLAG(Reclaim, reclaim, PF_NO_TAIL)
|
|
TESTCLEARFLAG(Reclaim, reclaim, PF_NO_TAIL)
|
|
PAGEFLAG(Readahead, readahead, PF_NO_COMPOUND)
|
|
TESTCLEARFLAG(Readahead, readahead, PF_NO_COMPOUND)
|
|
|
|
#ifdef CONFIG_HIGHMEM
|
|
/*
|
|
* Must use a macro here due to header dependency issues. page_zone() is not
|
|
* available at this point.
|
|
*/
|
|
#define PageHighMem(__p) is_highmem_idx(page_zonenum(__p))
|
|
#define folio_test_highmem(__f) is_highmem_idx(folio_zonenum(__f))
|
|
#else
|
|
PAGEFLAG_FALSE(HighMem, highmem)
|
|
#endif
|
|
|
|
#ifdef CONFIG_SWAP
|
|
static __always_inline bool folio_test_swapcache(struct folio *folio)
|
|
{
|
|
return folio_test_swapbacked(folio) &&
|
|
test_bit(PG_swapcache, folio_flags(folio, 0));
|
|
}
|
|
|
|
static __always_inline bool PageSwapCache(struct page *page)
|
|
{
|
|
return folio_test_swapcache(page_folio(page));
|
|
}
|
|
|
|
SETPAGEFLAG(SwapCache, swapcache, PF_NO_TAIL)
|
|
CLEARPAGEFLAG(SwapCache, swapcache, PF_NO_TAIL)
|
|
#else
|
|
PAGEFLAG_FALSE(SwapCache, swapcache)
|
|
#endif
|
|
|
|
PAGEFLAG(Unevictable, unevictable, PF_HEAD)
|
|
__CLEARPAGEFLAG(Unevictable, unevictable, PF_HEAD)
|
|
TESTCLEARFLAG(Unevictable, unevictable, PF_HEAD)
|
|
|
|
#ifdef CONFIG_MMU
|
|
PAGEFLAG(Mlocked, mlocked, PF_NO_TAIL)
|
|
__CLEARPAGEFLAG(Mlocked, mlocked, PF_NO_TAIL)
|
|
TESTSCFLAG(Mlocked, mlocked, PF_NO_TAIL)
|
|
#else
|
|
PAGEFLAG_FALSE(Mlocked, mlocked) __CLEARPAGEFLAG_NOOP(Mlocked, mlocked)
|
|
TESTSCFLAG_FALSE(Mlocked, mlocked)
|
|
#endif
|
|
|
|
#ifdef CONFIG_ARCH_USES_PG_UNCACHED
|
|
PAGEFLAG(Uncached, uncached, PF_NO_COMPOUND)
|
|
#else
|
|
PAGEFLAG_FALSE(Uncached, uncached)
|
|
#endif
|
|
|
|
#ifdef CONFIG_MEMORY_FAILURE
|
|
PAGEFLAG(HWPoison, hwpoison, PF_ANY)
|
|
TESTSCFLAG(HWPoison, hwpoison, PF_ANY)
|
|
#define __PG_HWPOISON (1UL << PG_hwpoison)
|
|
#define MAGIC_HWPOISON 0x48575053U /* HWPS */
|
|
extern void SetPageHWPoisonTakenOff(struct page *page);
|
|
extern void ClearPageHWPoisonTakenOff(struct page *page);
|
|
extern bool take_page_off_buddy(struct page *page);
|
|
extern bool put_page_back_buddy(struct page *page);
|
|
#else
|
|
PAGEFLAG_FALSE(HWPoison, hwpoison)
|
|
#define __PG_HWPOISON 0
|
|
#endif
|
|
|
|
#if defined(CONFIG_PAGE_IDLE_FLAG) && defined(CONFIG_64BIT)
|
|
TESTPAGEFLAG(Young, young, PF_ANY)
|
|
SETPAGEFLAG(Young, young, PF_ANY)
|
|
TESTCLEARFLAG(Young, young, PF_ANY)
|
|
PAGEFLAG(Idle, idle, PF_ANY)
|
|
#endif
|
|
|
|
#ifdef CONFIG_KASAN_HW_TAGS
|
|
PAGEFLAG(SkipKASanPoison, skip_kasan_poison, PF_HEAD)
|
|
#else
|
|
PAGEFLAG_FALSE(SkipKASanPoison, skip_kasan_poison)
|
|
#endif
|
|
|
|
/*
|
|
* PageReported() is used to track reported free pages within the Buddy
|
|
* allocator. We can use the non-atomic version of the test and set
|
|
* operations as both should be shielded with the zone lock to prevent
|
|
* any possible races on the setting or clearing of the bit.
|
|
*/
|
|
__PAGEFLAG(Reported, reported, PF_NO_COMPOUND)
|
|
|
|
#ifdef CONFIG_MEMORY_HOTPLUG
|
|
PAGEFLAG(VmemmapSelfHosted, vmemmap_self_hosted, PF_ANY)
|
|
#else
|
|
PAGEFLAG_FALSE(VmemmapSelfHosted, vmemmap_self_hosted)
|
|
#endif
|
|
|
|
/*
|
|
* On an anonymous page mapped into a user virtual memory area,
|
|
* page->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.
|
|
*
|
|
* 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
|
|
* 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 used for non-lru movable
|
|
* page and then page->mapping points to a struct movable_operations.
|
|
*
|
|
* 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 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(struct folio *folio)
|
|
{
|
|
return ((unsigned long)folio->mapping & PAGE_MAPPING_FLAGS) != 0;
|
|
}
|
|
|
|
static __always_inline int PageMappingFlags(struct page *page)
|
|
{
|
|
return ((unsigned long)page->mapping & PAGE_MAPPING_FLAGS) != 0;
|
|
}
|
|
|
|
static __always_inline bool folio_test_anon(struct folio *folio)
|
|
{
|
|
return ((unsigned long)folio->mapping & PAGE_MAPPING_ANON) != 0;
|
|
}
|
|
|
|
static __always_inline bool PageAnon(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 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"
|
|
* which KSM maps into multiple mms, wherever identical anonymous page content
|
|
* is found in VM_MERGEABLE vmas. It's a PageAnon page, pointing not to any
|
|
* anon_vma, but to that page's node of the stable tree.
|
|
*/
|
|
static __always_inline bool folio_test_ksm(struct folio *folio)
|
|
{
|
|
return ((unsigned long)folio->mapping & PAGE_MAPPING_FLAGS) ==
|
|
PAGE_MAPPING_KSM;
|
|
}
|
|
|
|
static __always_inline bool PageKsm(struct page *page)
|
|
{
|
|
return folio_test_ksm(page_folio(page));
|
|
}
|
|
#else
|
|
TESTPAGEFLAG_FALSE(Ksm, ksm)
|
|
#endif
|
|
|
|
u64 stable_page_flags(struct page *page);
|
|
|
|
/**
|
|
* folio_test_uptodate - Is this folio up to date?
|
|
* @folio: The folio.
|
|
*
|
|
* The uptodate flag is set on a folio when every byte in the folio is
|
|
* at least as new as the corresponding bytes on storage. Anonymous
|
|
* and CoW folios are always uptodate. If the folio is not uptodate,
|
|
* some of the bytes in it may be; see the is_partially_uptodate()
|
|
* address_space operation.
|
|
*/
|
|
static inline bool folio_test_uptodate(struct folio *folio)
|
|
{
|
|
bool ret = test_bit(PG_uptodate, folio_flags(folio, 0));
|
|
/*
|
|
* Must ensure that the data we read out of the folio is loaded
|
|
* _after_ we've loaded folio->flags to check the uptodate bit.
|
|
* We can skip the barrier if the folio is not uptodate, because
|
|
* we wouldn't be reading anything from it.
|
|
*
|
|
* See folio_mark_uptodate() for the other side of the story.
|
|
*/
|
|
if (ret)
|
|
smp_rmb();
|
|
|
|
return ret;
|
|
}
|
|
|
|
static inline int PageUptodate(struct page *page)
|
|
{
|
|
return folio_test_uptodate(page_folio(page));
|
|
}
|
|
|
|
static __always_inline void __folio_mark_uptodate(struct folio *folio)
|
|
{
|
|
smp_wmb();
|
|
__set_bit(PG_uptodate, folio_flags(folio, 0));
|
|
}
|
|
|
|
static __always_inline void folio_mark_uptodate(struct folio *folio)
|
|
{
|
|
/*
|
|
* Memory barrier must be issued before setting the PG_uptodate bit,
|
|
* so that all previous stores issued in order to bring the folio
|
|
* uptodate are actually visible before folio_test_uptodate becomes true.
|
|
*/
|
|
smp_wmb();
|
|
set_bit(PG_uptodate, folio_flags(folio, 0));
|
|
}
|
|
|
|
static __always_inline void __SetPageUptodate(struct page *page)
|
|
{
|
|
__folio_mark_uptodate((struct folio *)page);
|
|
}
|
|
|
|
static __always_inline void SetPageUptodate(struct page *page)
|
|
{
|
|
folio_mark_uptodate((struct folio *)page);
|
|
}
|
|
|
|
CLEARPAGEFLAG(Uptodate, uptodate, PF_NO_TAIL)
|
|
|
|
bool __folio_start_writeback(struct folio *folio, bool keep_write);
|
|
bool 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 inline void set_page_writeback_keepwrite(struct page *page)
|
|
{
|
|
folio_start_writeback_keepwrite(page_folio(page));
|
|
}
|
|
|
|
static inline bool test_set_page_writeback(struct page *page)
|
|
{
|
|
return set_page_writeback(page);
|
|
}
|
|
|
|
static __always_inline bool folio_test_head(struct folio *folio)
|
|
{
|
|
return test_bit(PG_head, folio_flags(folio, FOLIO_PF_ANY));
|
|
}
|
|
|
|
static __always_inline int PageHead(struct page *page)
|
|
{
|
|
PF_POISONED_CHECK(page);
|
|
return test_bit(PG_head, &page->flags) && !page_is_fake_head(page);
|
|
}
|
|
|
|
__SETPAGEFLAG(Head, head, PF_ANY)
|
|
__CLEARPAGEFLAG(Head, head, PF_ANY)
|
|
CLEARPAGEFLAG(Head, head, PF_ANY)
|
|
|
|
/**
|
|
* folio_test_large() - Does this folio contain more than one page?
|
|
* @folio: The folio to test.
|
|
*
|
|
* Return: True if the folio is larger than one page.
|
|
*/
|
|
static inline bool folio_test_large(struct folio *folio)
|
|
{
|
|
return folio_test_head(folio);
|
|
}
|
|
|
|
static __always_inline void set_compound_head(struct page *page, struct page *head)
|
|
{
|
|
WRITE_ONCE(page->compound_head, (unsigned long)head + 1);
|
|
}
|
|
|
|
static __always_inline void clear_compound_head(struct page *page)
|
|
{
|
|
WRITE_ONCE(page->compound_head, 0);
|
|
}
|
|
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
|
static inline void ClearPageCompound(struct page *page)
|
|
{
|
|
BUG_ON(!PageHead(page));
|
|
ClearPageHead(page);
|
|
}
|
|
#endif
|
|
|
|
#define PG_head_mask ((1UL << PG_head))
|
|
|
|
#ifdef CONFIG_HUGETLB_PAGE
|
|
int PageHuge(struct page *page);
|
|
int PageHeadHuge(struct page *page);
|
|
static inline bool folio_test_hugetlb(struct folio *folio)
|
|
{
|
|
return PageHeadHuge(&folio->page);
|
|
}
|
|
#else
|
|
TESTPAGEFLAG_FALSE(Huge, hugetlb)
|
|
TESTPAGEFLAG_FALSE(HeadHuge, headhuge)
|
|
#endif
|
|
|
|
#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(struct page *page)
|
|
{
|
|
VM_BUG_ON_PAGE(PageTail(page), page);
|
|
return PageHead(page);
|
|
}
|
|
|
|
static inline bool folio_test_transhuge(struct folio *folio)
|
|
{
|
|
return folio_test_head(folio);
|
|
}
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
static inline int PageTransCompound(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(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)
|
|
/*
|
|
* PageHasHWPoisoned indicates that at least one subpage is hwpoisoned in the
|
|
* compound page.
|
|
*
|
|
* 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)
|
|
#else
|
|
PAGEFLAG_FALSE(HasHWPoisoned, has_hwpoisoned)
|
|
TESTSCFLAG_FALSE(HasHWPoisoned, has_hwpoisoned)
|
|
#endif
|
|
|
|
/*
|
|
* Check if a page is currently marked HWPoisoned. Note that this check is
|
|
* best effort only and inherently racy: there is no way to synchronize with
|
|
* failing hardware.
|
|
*/
|
|
static inline bool is_page_hwpoison(struct page *page)
|
|
{
|
|
if (PageHWPoison(page))
|
|
return true;
|
|
return PageHuge(page) && PageHWPoison(compound_head(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_TYPE_BASE 0xf0000000
|
|
/* Reserve 0x0000007f to catch underflows of page_mapcount */
|
|
#define PAGE_MAPCOUNT_RESERVE -128
|
|
#define PG_buddy 0x00000080
|
|
#define PG_offline 0x00000100
|
|
#define PG_table 0x00000200
|
|
#define PG_guard 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 PageType(page, PG_##lname); \
|
|
} \
|
|
static __always_inline void __SetPage##uname(struct page *page) \
|
|
{ \
|
|
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); \
|
|
page->page_type |= PG_##lname; \
|
|
}
|
|
|
|
/*
|
|
* PageBuddy() indicates that the page is free and in the buddy system
|
|
* (see mm/page_alloc.c).
|
|
*/
|
|
PAGE_TYPE_OPS(Buddy, buddy)
|
|
|
|
/*
|
|
* PageOffline() indicates that the page is logically offline although the
|
|
* containing section is online. (e.g. inflated in a balloon driver or
|
|
* not onlined when onlining the section).
|
|
* The content of these pages is effectively stale. Such pages should not
|
|
* be touched (read/write/dump/save) except by their owner.
|
|
*
|
|
* If a driver wants to allow to offline unmovable PageOffline() pages without
|
|
* putting them back to the buddy, it can do so via the memory notifier by
|
|
* decrementing the reference count in MEM_GOING_OFFLINE and incrementing the
|
|
* reference count in MEM_CANCEL_OFFLINE. When offlining, the PageOffline()
|
|
* pages (now with a reference count of zero) are treated like free pages,
|
|
* allowing the containing memory block to get offlined. A driver that
|
|
* relies on this feature is aware that re-onlining the memory block will
|
|
* require to re-set the pages PageOffline() and not giving them to the
|
|
* buddy via online_page_callback_t.
|
|
*
|
|
* There are drivers that mark a page PageOffline() and expect there won't be
|
|
* any further access to page content. PFN walkers that read content of random
|
|
* pages should check PageOffline() and synchronize with such drivers using
|
|
* page_offline_freeze()/page_offline_thaw().
|
|
*/
|
|
PAGE_TYPE_OPS(Offline, offline)
|
|
|
|
extern void page_offline_freeze(void);
|
|
extern void page_offline_thaw(void);
|
|
extern void page_offline_begin(void);
|
|
extern void page_offline_end(void);
|
|
|
|
/*
|
|
* Marks pages in use as page tables.
|
|
*/
|
|
PAGE_TYPE_OPS(Table, table)
|
|
|
|
/*
|
|
* Marks guardpages used with debug_pagealloc.
|
|
*/
|
|
PAGE_TYPE_OPS(Guard, guard)
|
|
|
|
extern bool is_free_buddy_page(struct page *page);
|
|
|
|
PAGEFLAG(Isolated, isolated, PF_ANY);
|
|
|
|
static __always_inline int PageAnonExclusive(struct page *page)
|
|
{
|
|
VM_BUG_ON_PGFLAGS(!PageAnon(page), page);
|
|
VM_BUG_ON_PGFLAGS(PageHuge(page) && !PageHead(page), page);
|
|
return test_bit(PG_anon_exclusive, &PF_ANY(page, 1)->flags);
|
|
}
|
|
|
|
static __always_inline void SetPageAnonExclusive(struct page *page)
|
|
{
|
|
VM_BUG_ON_PGFLAGS(!PageAnon(page) || PageKsm(page), page);
|
|
VM_BUG_ON_PGFLAGS(PageHuge(page) && !PageHead(page), page);
|
|
set_bit(PG_anon_exclusive, &PF_ANY(page, 1)->flags);
|
|
}
|
|
|
|
static __always_inline void ClearPageAnonExclusive(struct page *page)
|
|
{
|
|
VM_BUG_ON_PGFLAGS(!PageAnon(page) || PageKsm(page), page);
|
|
VM_BUG_ON_PGFLAGS(PageHuge(page) && !PageHead(page), page);
|
|
clear_bit(PG_anon_exclusive, &PF_ANY(page, 1)->flags);
|
|
}
|
|
|
|
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);
|
|
}
|
|
|
|
#ifdef CONFIG_MMU
|
|
#define __PG_MLOCKED (1UL << PG_mlocked)
|
|
#else
|
|
#define __PG_MLOCKED 0
|
|
#endif
|
|
|
|
/*
|
|
* Flags checked when a page is freed. Pages being freed should not have
|
|
* these flags set. If they are, there is a problem.
|
|
*/
|
|
#define PAGE_FLAGS_CHECK_AT_FREE \
|
|
(1UL << PG_lru | 1UL << PG_locked | \
|
|
1UL << PG_private | 1UL << PG_private_2 | \
|
|
1UL << PG_writeback | 1UL << PG_reserved | \
|
|
1UL << PG_slab | 1UL << PG_active | \
|
|
1UL << PG_unevictable | __PG_MLOCKED | LRU_GEN_MASK)
|
|
|
|
/*
|
|
* Flags checked when a page is prepped for return by the page allocator.
|
|
* Pages being prepped should not have these flags set. If they are set,
|
|
* there has been a kernel bug or struct page corruption.
|
|
*
|
|
* __PG_HWPOISON is exceptional because it needs to be kept beyond page's
|
|
* alloc-free cycle to prevent from reusing the page.
|
|
*/
|
|
#define PAGE_FLAGS_CHECK_AT_PREP \
|
|
((PAGEFLAGS_MASK & ~__PG_HWPOISON) | LRU_GEN_MASK | LRU_REFS_MASK)
|
|
|
|
#define PAGE_FLAGS_PRIVATE \
|
|
(1UL << PG_private | 1UL << PG_private_2)
|
|
/**
|
|
* page_has_private - Determine if page has private stuff
|
|
* @page: The page to be checked
|
|
*
|
|
* Determine if a page has private stuff, indicating that release routines
|
|
* should be invoked upon it.
|
|
*/
|
|
static inline int page_has_private(struct page *page)
|
|
{
|
|
return !!(page->flags & PAGE_FLAGS_PRIVATE);
|
|
}
|
|
|
|
static inline bool folio_has_private(struct folio *folio)
|
|
{
|
|
return page_has_private(&folio->page);
|
|
}
|
|
|
|
#undef PF_ANY
|
|
#undef PF_HEAD
|
|
#undef PF_ONLY_HEAD
|
|
#undef PF_NO_TAIL
|
|
#undef PF_NO_COMPOUND
|
|
#undef PF_SECOND
|
|
#endif /* !__GENERATING_BOUNDS_H */
|
|
|
|
#endif /* PAGE_FLAGS_H */
|