--- /dev/null
+/*
+ * 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, which can never be swapped out. Some
+ * of them might not even exist (eg empty_bad_page)...
+ *
+ * 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_uptodate tells whether the page's contents is valid. When a read
+ * completes, the page becomes uptodate, unless a disk I/O error happened.
+ *
+ * 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_highmem pages are not permanently mapped into the kernel virtual address
+ * space, they need to be kmapped separately for doing IO on the pages. The
+ * struct page (these bits with information) are always mapped into kernel
+ * address space...
+ *
+ * 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 *_dontuse flags. Use the macros. Otherwise you'll break
+ * locked- and dirty-page accounting.
+ *
+ * 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_error,
+ PG_referenced,
+ PG_uptodate,
+ PG_dirty,
+ PG_lru,
+ PG_active,
+ 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 */
+#ifdef CONFIG_PAGEFLAGS_EXTENDED
+ PG_head, /* A head page */
+ PG_tail, /* A tail page */
+#else
+ PG_compound, /* A compound page */
+#endif
+ PG_swapcache, /* Swap page: swp_entry_t in private */
+ 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
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+ PG_compound_lock,
+#endif
+ __NR_PAGEFLAGS,
+
+ /* Filesystems */
+ PG_checked = PG_owner_priv_1,
+
+ /* 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,
+
+ /* SLOB */
+ PG_slob_free = PG_private,
+};
+
+#ifndef __GENERATING_BOUNDS_H
+
+/*
+ * Macros to create function definitions for page flags
+ */
+#define TESTPAGEFLAG(uname, lname) \
+static inline int Page##uname(const struct page *page) \
+ { return test_bit(PG_##lname, &page->flags); }
+
+#define SETPAGEFLAG(uname, lname) \
+static inline void SetPage##uname(struct page *page) \
+ { set_bit(PG_##lname, &page->flags); }
+
+#define CLEARPAGEFLAG(uname, lname) \
+static inline void ClearPage##uname(struct page *page) \
+ { clear_bit(PG_##lname, &page->flags); }
+
+#define __SETPAGEFLAG(uname, lname) \
+static inline void __SetPage##uname(struct page *page) \
+ { __set_bit(PG_##lname, &page->flags); }
+
+#define __CLEARPAGEFLAG(uname, lname) \
+static inline void __ClearPage##uname(struct page *page) \
+ { __clear_bit(PG_##lname, &page->flags); }
+
+#define TESTSETFLAG(uname, lname) \
+static inline int TestSetPage##uname(struct page *page) \
+ { return test_and_set_bit(PG_##lname, &page->flags); }
+
+#define TESTCLEARFLAG(uname, lname) \
+static inline int TestClearPage##uname(struct page *page) \
+ { return test_and_clear_bit(PG_##lname, &page->flags); }
+
+#define __TESTCLEARFLAG(uname, lname) \
+static inline int __TestClearPage##uname(struct page *page) \
+ { return __test_and_clear_bit(PG_##lname, &page->flags); }
+
+#define PAGEFLAG(uname, lname) TESTPAGEFLAG(uname, lname) \
+ SETPAGEFLAG(uname, lname) CLEARPAGEFLAG(uname, lname)
+
+#define __PAGEFLAG(uname, lname) TESTPAGEFLAG(uname, lname) \
+ __SETPAGEFLAG(uname, lname) __CLEARPAGEFLAG(uname, lname)
+
+#define TESTSCFLAG(uname, lname) \
+ TESTSETFLAG(uname, lname) TESTCLEARFLAG(uname, lname)
+
+#define TESTPAGEFLAG_FALSE(uname) \
+static inline int Page##uname(const struct page *page) { return 0; }
+
+#define SETPAGEFLAG_NOOP(uname) \
+static inline void SetPage##uname(struct page *page) { }
+
+#define CLEARPAGEFLAG_NOOP(uname) \
+static inline void ClearPage##uname(struct page *page) { }
+
+#define __CLEARPAGEFLAG_NOOP(uname) \
+static inline void __ClearPage##uname(struct page *page) { }
+
+#define TESTSETFLAG_FALSE(uname) \
+static inline int TestSetPage##uname(struct page *page) { return 0; }
+
+#define TESTCLEARFLAG_FALSE(uname) \
+static inline int TestClearPage##uname(struct page *page) { return 0; }
+
+#define __TESTCLEARFLAG_FALSE(uname) \
+static inline int __TestClearPage##uname(struct page *page) { return 0; }
+
+#define PAGEFLAG_FALSE(uname) TESTPAGEFLAG_FALSE(uname) \
+ SETPAGEFLAG_NOOP(uname) CLEARPAGEFLAG_NOOP(uname)
+
+#define TESTSCFLAG_FALSE(uname) \
+ TESTSETFLAG_FALSE(uname) TESTCLEARFLAG_FALSE(uname)
+
+struct page; /* forward declaration */
+
+TESTPAGEFLAG(Locked, locked)
+PAGEFLAG(Error, error) TESTCLEARFLAG(Error, error)
+PAGEFLAG(Referenced, referenced) TESTCLEARFLAG(Referenced, referenced)
+ __SETPAGEFLAG(Referenced, referenced)
+PAGEFLAG(Dirty, dirty) TESTSCFLAG(Dirty, dirty) __CLEARPAGEFLAG(Dirty, dirty)
+PAGEFLAG(LRU, lru) __CLEARPAGEFLAG(LRU, lru)
+PAGEFLAG(Active, active) __CLEARPAGEFLAG(Active, active)
+ TESTCLEARFLAG(Active, active)
+__PAGEFLAG(Slab, slab)
+PAGEFLAG(Checked, checked) /* Used by some filesystems */
+PAGEFLAG(Pinned, pinned) TESTSCFLAG(Pinned, pinned) /* Xen */
+PAGEFLAG(SavePinned, savepinned); /* Xen */
+PAGEFLAG(Foreign, foreign); /* Xen */
+PAGEFLAG(Reserved, reserved) __CLEARPAGEFLAG(Reserved, reserved)
+PAGEFLAG(SwapBacked, swapbacked) __CLEARPAGEFLAG(SwapBacked, swapbacked)
+ __SETPAGEFLAG(SwapBacked, swapbacked)
+
+__PAGEFLAG(SlobFree, slob_free)
+
+/*
+ * 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 releasepage() and co to be invoked
+ */
+PAGEFLAG(Private, private) __SETPAGEFLAG(Private, private)
+ __CLEARPAGEFLAG(Private, private)
+PAGEFLAG(Private2, private_2) TESTSCFLAG(Private2, private_2)
+PAGEFLAG(OwnerPriv1, owner_priv_1) TESTCLEARFLAG(OwnerPriv1, owner_priv_1)
+
+/*
+ * Only test-and-set exist for PG_writeback. The unconditional operators are
+ * risky: they bypass page accounting.
+ */
+TESTPAGEFLAG(Writeback, writeback) TESTSCFLAG(Writeback, writeback)
+PAGEFLAG(MappedToDisk, mappedtodisk)
+
+/* PG_readahead is only used for reads; PG_reclaim is only for writes */
+PAGEFLAG(Reclaim, reclaim) TESTCLEARFLAG(Reclaim, reclaim)
+PAGEFLAG(Readahead, reclaim) TESTCLEARFLAG(Readahead, reclaim)
+
+#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(page_zone(__p))
+#else
+PAGEFLAG_FALSE(HighMem)
+#endif
+
+#ifdef CONFIG_SWAP
+PAGEFLAG(SwapCache, swapcache)
+#else
+PAGEFLAG_FALSE(SwapCache)
+#endif
+
+PAGEFLAG(Unevictable, unevictable) __CLEARPAGEFLAG(Unevictable, unevictable)
+ TESTCLEARFLAG(Unevictable, unevictable)
+
+#ifdef CONFIG_MMU
+PAGEFLAG(Mlocked, mlocked) __CLEARPAGEFLAG(Mlocked, mlocked)
+ TESTSCFLAG(Mlocked, mlocked) __TESTCLEARFLAG(Mlocked, mlocked)
+#else
+PAGEFLAG_FALSE(Mlocked) __CLEARPAGEFLAG_NOOP(Mlocked)
+ TESTSCFLAG_FALSE(Mlocked) __TESTCLEARFLAG_FALSE(Mlocked)
+#endif
+
+#ifdef CONFIG_ARCH_USES_PG_UNCACHED
+PAGEFLAG(Uncached, uncached)
+#else
+PAGEFLAG_FALSE(Uncached)
+#endif
+
+#ifdef CONFIG_MEMORY_FAILURE
+PAGEFLAG(HWPoison, hwpoison)
+TESTSCFLAG(HWPoison, hwpoison)
+#define __PG_HWPOISON (1UL << PG_hwpoison)
+#else
+PAGEFLAG_FALSE(HWPoison)
+#define __PG_HWPOISON 0
+#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_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
+ * structure which KSM associates with that merged page. See ksm.h.
+ *
+ * PAGE_MAPPING_KSM without PAGE_MAPPING_ANON is currently never used.
+ *
+ * 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)
+
+static inline int PageAnon(struct page *page)
+{
+ return ((unsigned long)page->mapping & PAGE_MAPPING_ANON) != 0;
+}
+
+#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 inline int PageKsm(struct page *page)
+{
+ return ((unsigned long)page->mapping & PAGE_MAPPING_FLAGS) ==
+ (PAGE_MAPPING_ANON | PAGE_MAPPING_KSM);
+}
+#else
+TESTPAGEFLAG_FALSE(Ksm)
+#endif
+
+u64 stable_page_flags(struct page *page);
+
+static inline int PageUptodate(struct page *page)
+{
+ int ret = test_bit(PG_uptodate, &(page)->flags);
+
+ /*
+ * Must ensure that the data we read out of the page is loaded
+ * _after_ we've loaded page->flags to check for PageUptodate.
+ * We can skip the barrier if the page is not uptodate, because
+ * we wouldn't be reading anything from it.
+ *
+ * See SetPageUptodate() for the other side of the story.
+ */
+ if (ret)
+ smp_rmb();
+
+ return ret;
+}
+
+static inline void __SetPageUptodate(struct page *page)
+{
+ smp_wmb();
+ __set_bit(PG_uptodate, &(page)->flags);
+}
+
+static inline void SetPageUptodate(struct page *page)
+{
+ /*
+ * Memory barrier must be issued before setting the PG_uptodate bit,
+ * so that all previous stores issued in order to bring the page
+ * uptodate are actually visible before PageUptodate becomes true.
+ */
+ smp_wmb();
+ set_bit(PG_uptodate, &(page)->flags);
+}
+
+CLEARPAGEFLAG(Uptodate, uptodate)
+
+int test_clear_page_writeback(struct page *page);
+int __test_set_page_writeback(struct page *page, bool keep_write);
+
+#define test_set_page_writeback(page) \
+ __test_set_page_writeback(page, false)
+#define test_set_page_writeback_keepwrite(page) \
+ __test_set_page_writeback(page, true)
+
+static inline void set_page_writeback(struct page *page)
+{
+ test_set_page_writeback(page);
+}
+
+static inline void set_page_writeback_keepwrite(struct page *page)
+{
+ test_set_page_writeback_keepwrite(page);
+}
+
+#ifdef CONFIG_PAGEFLAGS_EXTENDED
+/*
+ * System with lots of page flags available. This allows separate
+ * flags for PageHead() and PageTail() checks of compound pages so that bit
+ * tests can be used in performance sensitive paths. PageCompound is
+ * generally not used in hot code paths except arch/powerpc/mm/init_64.c
+ * and arch/powerpc/kvm/book3s_64_vio_hv.c which use it to detect huge pages
+ * and avoid handling those in real mode.
+ */
+__PAGEFLAG(Head, head) CLEARPAGEFLAG(Head, head)
+__PAGEFLAG(Tail, tail)
+
+static inline int PageCompound(struct page *page)
+{
+ return page->flags & ((1L << PG_head) | (1L << PG_tail));
+
+}
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+static inline void ClearPageCompound(struct page *page)
+{
+ BUG_ON(!PageHead(page));
+ ClearPageHead(page);
+}
+#endif
+
+#define PG_head_mask ((1L << PG_head))
+
+#else
+/*
+ * Reduce page flag use as much as possible by overlapping
+ * compound page flags with the flags used for page cache pages. Possible
+ * because PageCompound is always set for compound pages and not for
+ * pages on the LRU and/or pagecache.
+ */
+TESTPAGEFLAG(Compound, compound)
+__SETPAGEFLAG(Head, compound) __CLEARPAGEFLAG(Head, compound)
+
+/*
+ * PG_reclaim is used in combination with PG_compound to mark the
+ * head and tail of a compound page. This saves one page flag
+ * but makes it impossible to use compound pages for the page cache.
+ * The PG_reclaim bit would have to be used for reclaim or readahead
+ * if compound pages enter the page cache.
+ *
+ * PG_compound & PG_reclaim => Tail page
+ * PG_compound & ~PG_reclaim => Head page
+ */
+#define PG_head_mask ((1L << PG_compound))
+#define PG_head_tail_mask ((1L << PG_compound) | (1L << PG_reclaim))
+
+static inline int PageHead(struct page *page)
+{
+ return ((page->flags & PG_head_tail_mask) == PG_head_mask);
+}
+
+static inline int PageTail(struct page *page)
+{
+ return ((page->flags & PG_head_tail_mask) == PG_head_tail_mask);
+}
+
+static inline void __SetPageTail(struct page *page)
+{
+ page->flags |= PG_head_tail_mask;
+}
+
+static inline void __ClearPageTail(struct page *page)
+{
+ page->flags &= ~PG_head_tail_mask;
+}
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+static inline void ClearPageCompound(struct page *page)
+{
+ BUG_ON((page->flags & PG_head_tail_mask) != (1 << PG_compound));
+ clear_bit(PG_compound, &page->flags);
+}
+#endif
+
+#endif /* !PAGEFLAGS_EXTENDED */
+
+#ifdef CONFIG_HUGETLB_PAGE
+int PageHuge(struct page *page);
+int PageHeadHuge(struct page *page);
+bool page_huge_active(struct page *page);
+#else
+TESTPAGEFLAG_FALSE(Huge)
+TESTPAGEFLAG_FALSE(HeadHuge)
+
+static inline bool page_huge_active(struct page *page)
+{
+ return 0;
+}
+#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);
+}
+
+/*
+ * 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
+
+static inline int PageTransHuge(struct page *page)
+{
+ return 0;
+}
+
+static inline int PageTransCompound(struct page *page)
+{
+ return 0;
+}
+
+static inline int PageTransTail(struct page *page)
+{
+ return 0;
+}
+#endif
+
+/*
+ * 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;
+}
+
+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);
+}
+
+static inline void __ClearPageBuddy(struct page *page)
+{
+ VM_BUG_ON_PAGE(!PageBuddy(page), page);
+ atomic_set(&page->_mapcount, -1);
+}
+
+#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);
+}
+
+/*
+ * If network-based swap is enabled, sl*b must keep track of whether pages
+ * were allocated from pfmemalloc reserves.
+ */
+static inline int PageSlabPfmemalloc(struct page *page)
+{
+ VM_BUG_ON_PAGE(!PageSlab(page), page);
+ return PageActive(page);
+}
+
+static inline void SetPageSlabPfmemalloc(struct page *page)
+{
+ VM_BUG_ON_PAGE(!PageSlab(page), page);
+ SetPageActive(page);
+}
+
+static inline void __ClearPageSlabPfmemalloc(struct page *page)
+{
+ VM_BUG_ON_PAGE(!PageSlab(page), page);
+ __ClearPageActive(page);
+}
+
+static inline void ClearPageSlabPfmemalloc(struct page *page)
+{
+ VM_BUG_ON_PAGE(!PageSlab(page), page);
+ ClearPageActive(page);
+}
+
+#ifdef CONFIG_MMU
+#define __PG_MLOCKED (1 << PG_mlocked)
+#else
+#define __PG_MLOCKED 0
+#endif
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+#define __PG_COMPOUND_LOCK (1 << PG_compound_lock)
+#else
+#define __PG_COMPOUND_LOCK 0
+#endif
+
+/*
+ * Flags checked when a page is freed. Pages being freed should not have
+ * 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 | __PG_HWPOISON | \
+ __PG_COMPOUND_LOCK)
+
+/*
+ * Flags checked when a page is prepped for return by the page allocator.
+ * Pages being prepped should not have any flags set. It they are set,
+ * there has been a kernel bug or struct page corruption.
+ */
+#define PAGE_FLAGS_CHECK_AT_PREP ((1 << NR_PAGEFLAGS) - 1)
+
+#define PAGE_FLAGS_PRIVATE \
+ (1 << PG_private | 1 << 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);
+}
+
+#endif /* !__GENERATING_BOUNDS_H */
+
+#endif /* PAGE_FLAGS_H */
Code Review / kvmfornfv.git / blobdiff