Moved, renamed, and deleted files

The original directory structure was scattered and unorganized.
Changes are basically to make it look like kernel structure.

1 files changed, 503 insertions, 0 deletions

diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
new file mode 100644
index 00000000..c88d2a94
--- /dev/null
+++ b/include/linux/page-flags.h
@@ -0,0 +1,503 @@
+/*
+ * Macros for manipulating and testing page->flags
+ */
+
+#ifndef PAGE_FLAGS_H
+#define PAGE_FLAGS_H
+
+#include <linux/types.h>
+#include <linux/bug.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 */
+	PG_pinned = PG_owner_priv_1,
+	PG_savepinned = PG_dirty,
+
+	/* 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 PAGEFLAG_FALSE(uname) 						\
+static inline int Page##uname(const struct page *page)			\
+			{ return 0; }
+
+#define TESTSCFLAG(uname, lname)					\
+	TESTSETFLAG(uname, lname) TESTCLEARFLAG(uname, lname)
+
+#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 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; }
+
+struct page;	/* forward declaration */
+
+TESTPAGEFLAG(Locked, locked)
+PAGEFLAG(Error, error) TESTCLEARFLAG(Error, error)
+PAGEFLAG(Referenced, referenced) TESTCLEARFLAG(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(Reserved, reserved) __CLEARPAGEFLAG(Reserved, reserved)
+PAGEFLAG(SwapBacked, swapbacked) __CLEARPAGEFLAG(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 file reads; PG_reclaim is only for writes */
+PAGEFLAG(Reclaim, reclaim) TESTCLEARFLAG(Reclaim, reclaim)
+PAGEFLAG(Readahead, reclaim)		/* Reminder to do async read-ahead */
+
+#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)
+	SETPAGEFLAG_NOOP(SwapCache) CLEARPAGEFLAG_NOOP(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) SETPAGEFLAG_NOOP(Mlocked)
+	TESTCLEARFLAG_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
+
+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)
+{
+#ifdef CONFIG_S390
+	if (!test_and_set_bit(PG_uptodate, &page->flags))
+		page_set_storage_key(page_to_phys(page), PAGE_DEFAULT_KEY, 0);
+#else
+	/*
+	 * 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.
+	 *
+	 * s390 doesn't need an explicit smp_wmb here because the test and
+	 * set bit already provides full barriers.
+	 */
+	smp_wmb();
+	set_bit(PG_uptodate, &(page)->flags);
+#endif
+}
+
+CLEARPAGEFLAG(Uptodate, uptodate)
+
+extern void cancel_dirty_page(struct page *page, unsigned int account_size);
+
+int test_clear_page_writeback(struct page *page);
+int test_set_page_writeback(struct page *page);
+
+static inline void set_page_writeback(struct page *page)
+{
+	test_set_page_writeback(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.
+ */
+__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
+#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)
+__PAGEFLAG(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_tail_mask ((1L << PG_compound) | (1L << PG_reclaim))
+
+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_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(PageTail(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
+
+#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 */