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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Macros for manipulating and testing page->flags
3 */
4
5#ifndef PAGE_FLAGS_H
6#define PAGE_FLAGS_H
7
Andrew Mortonf886ed42006-06-23 02:03:06 -07008#include <linux/types.h>
Paul Gortmaker187f1882011-11-23 20:12:59 -05009#include <linux/bug.h>
Mel Gorman072bb0a2012-07-31 16:43:58 -070010#include <linux/mmdebug.h>
Christoph Lameter9223b412008-04-28 02:12:48 -070011#ifndef __GENERATING_BOUNDS_H
Christoph Lameter6d777952007-05-06 14:49:40 -070012#include <linux/mm_types.h>
Sam Ravnborg01fc0ac2009-04-19 21:57:19 +020013#include <generated/bounds.h>
Christoph Lameter9223b412008-04-28 02:12:48 -070014#endif /* !__GENERATING_BOUNDS_H */
Andrew Mortonf886ed42006-06-23 02:03:06 -070015
Linus Torvalds1da177e2005-04-16 15:20:36 -070016/*
17 * Various page->flags bits:
18 *
19 * PG_reserved is set for special pages, which can never be swapped out. Some
20 * of them might not even exist (eg empty_bad_page)...
21 *
Nick Pigginda6052f2006-09-25 23:31:35 -070022 * The PG_private bitflag is set on pagecache pages if they contain filesystem
23 * specific data (which is normally at page->private). It can be used by
24 * private allocations for its own usage.
Linus Torvalds1da177e2005-04-16 15:20:36 -070025 *
Nick Pigginda6052f2006-09-25 23:31:35 -070026 * During initiation of disk I/O, PG_locked is set. This bit is set before I/O
27 * and cleared when writeback _starts_ or when read _completes_. PG_writeback
28 * is set before writeback starts and cleared when it finishes.
29 *
30 * PG_locked also pins a page in pagecache, and blocks truncation of the file
31 * while it is held.
32 *
33 * page_waitqueue(page) is a wait queue of all tasks waiting for the page
34 * to become unlocked.
Linus Torvalds1da177e2005-04-16 15:20:36 -070035 *
36 * PG_uptodate tells whether the page's contents is valid. When a read
37 * completes, the page becomes uptodate, unless a disk I/O error happened.
38 *
Nick Pigginda6052f2006-09-25 23:31:35 -070039 * PG_referenced, PG_reclaim are used for page reclaim for anonymous and
40 * file-backed pagecache (see mm/vmscan.c).
Linus Torvalds1da177e2005-04-16 15:20:36 -070041 *
42 * PG_error is set to indicate that an I/O error occurred on this page.
43 *
44 * PG_arch_1 is an architecture specific page state bit. The generic code
45 * guarantees that this bit is cleared for a page when it first is entered into
46 * the page cache.
47 *
48 * PG_highmem pages are not permanently mapped into the kernel virtual address
49 * space, they need to be kmapped separately for doing IO on the pages. The
50 * struct page (these bits with information) are always mapped into kernel
51 * address space...
Nick Pigginda6052f2006-09-25 23:31:35 -070052 *
Andi Kleend466f2f2009-09-16 11:50:03 +020053 * PG_hwpoison indicates that a page got corrupted in hardware and contains
54 * data with incorrect ECC bits that triggered a machine check. Accessing is
55 * not safe since it may cause another machine check. Don't touch!
Linus Torvalds1da177e2005-04-16 15:20:36 -070056 */
57
58/*
59 * Don't use the *_dontuse flags. Use the macros. Otherwise you'll break
Andy Whitcroft91fc8ab2006-04-10 22:53:01 -070060 * locked- and dirty-page accounting.
61 *
62 * The page flags field is split into two parts, the main flags area
63 * which extends from the low bits upwards, and the fields area which
64 * extends from the high bits downwards.
65 *
66 * | FIELD | ... | FLAGS |
Christoph Lameter9223b412008-04-28 02:12:48 -070067 * N-1 ^ 0
68 * (NR_PAGEFLAGS)
Andy Whitcroft91fc8ab2006-04-10 22:53:01 -070069 *
Christoph Lameter9223b412008-04-28 02:12:48 -070070 * The fields area is reserved for fields mapping zone, node (for NUMA) and
71 * SPARSEMEM section (for variants of SPARSEMEM that require section ids like
72 * SPARSEMEM_EXTREME with !SPARSEMEM_VMEMMAP).
Linus Torvalds1da177e2005-04-16 15:20:36 -070073 */
Christoph Lametere2683182008-04-28 02:12:47 -070074enum pageflags {
75 PG_locked, /* Page is locked. Don't touch. */
76 PG_error,
77 PG_referenced,
78 PG_uptodate,
79 PG_dirty,
80 PG_lru,
81 PG_active,
82 PG_slab,
83 PG_owner_priv_1, /* Owner use. If pagecache, fs may use*/
Christoph Lametere2683182008-04-28 02:12:47 -070084 PG_arch_1,
85 PG_reserved,
86 PG_private, /* If pagecache, has fs-private data */
David Howells266cf652009-04-03 16:42:36 +010087 PG_private_2, /* If pagecache, has fs aux data */
Christoph Lametere2683182008-04-28 02:12:47 -070088 PG_writeback, /* Page is under writeback */
Christoph Lametere20b8cc2008-04-28 02:12:55 -070089 PG_head, /* A head page */
Christoph Lametere2683182008-04-28 02:12:47 -070090 PG_swapcache, /* Swap page: swp_entry_t in private */
91 PG_mappedtodisk, /* Has blocks allocated on-disk */
92 PG_reclaim, /* To be reclaimed asap */
Rik van Rielb2e18532008-10-18 20:26:30 -070093 PG_swapbacked, /* Page is backed by RAM/swap */
Lee Schermerhorn894bc312008-10-18 20:26:39 -070094 PG_unevictable, /* Page is "unevictable" */
Hugh Dickinsaf8e3352009-12-14 17:58:59 -080095#ifdef CONFIG_MMU
Nick Pigginb291f002008-10-18 20:26:44 -070096 PG_mlocked, /* Page is vma mlocked */
Lee Schermerhorn894bc312008-10-18 20:26:39 -070097#endif
Venkatesh Pallipadi46cf98c2009-07-10 09:57:37 -070098#ifdef CONFIG_ARCH_USES_PG_UNCACHED
Christoph Lameter602c4d12008-04-28 02:12:52 -070099 PG_uncached, /* Page has been mapped as uncached */
Andrew Mortonf886ed42006-06-23 02:03:06 -0700100#endif
Andi Kleend466f2f2009-09-16 11:50:03 +0200101#ifdef CONFIG_MEMORY_FAILURE
102 PG_hwpoison, /* hardware poisoned page. Don't touch */
103#endif
Vladimir Davydov33c3fc72015-09-09 15:35:45 -0700104#if defined(CONFIG_IDLE_PAGE_TRACKING) && defined(CONFIG_64BIT)
105 PG_young,
106 PG_idle,
107#endif
Andy Whitcroft0cad47c2008-07-23 21:27:16 -0700108 __NR_PAGEFLAGS,
109
110 /* Filesystems */
111 PG_checked = PG_owner_priv_1,
112
David Howells266cf652009-04-03 16:42:36 +0100113 /* Two page bits are conscripted by FS-Cache to maintain local caching
114 * state. These bits are set on pages belonging to the netfs's inodes
115 * when those inodes are being locally cached.
116 */
117 PG_fscache = PG_private_2, /* page backed by cache */
118
Andy Whitcroft0cad47c2008-07-23 21:27:16 -0700119 /* XEN */
Jennifer Herbertd8ac3dd2015-01-05 13:24:09 +0000120 /* Pinned in Xen as a read-only pagetable page. */
Andy Whitcroft0cad47c2008-07-23 21:27:16 -0700121 PG_pinned = PG_owner_priv_1,
Jennifer Herbertd8ac3dd2015-01-05 13:24:09 +0000122 /* Pinned as part of domain save (see xen_mm_pin_all()). */
Andy Whitcroft0cad47c2008-07-23 21:27:16 -0700123 PG_savepinned = PG_dirty,
Jennifer Herbertd8ac3dd2015-01-05 13:24:09 +0000124 /* Has a grant mapping of another (foreign) domain's page. */
125 PG_foreign = PG_owner_priv_1,
Andy Whitcroft8a380822008-07-23 21:27:18 -0700126
Andy Whitcroft9023cb72008-07-23 21:27:19 -0700127 /* SLOB */
Andy Whitcroft9023cb72008-07-23 21:27:19 -0700128 PG_slob_free = PG_private,
Kirill A. Shutemov53f92632016-01-15 16:53:42 -0800129
130 /* Compound pages. Stored in first tail page's flags */
131 PG_double_map = PG_private_2,
Minchan Kimbda807d2016-07-26 15:23:05 -0700132
133 /* non-lru isolated movable page */
134 PG_isolated = PG_reclaim,
Christoph Lametere2683182008-04-28 02:12:47 -0700135};
Linus Torvalds1da177e2005-04-16 15:20:36 -0700136
Christoph Lameter9223b412008-04-28 02:12:48 -0700137#ifndef __GENERATING_BOUNDS_H
138
Kirill A. Shutemov0e6d31a2016-01-15 16:51:17 -0800139struct page; /* forward declaration */
140
141static inline struct page *compound_head(struct page *page)
142{
143 unsigned long head = READ_ONCE(page->compound_head);
144
145 if (unlikely(head & 1))
146 return (struct page *) (head - 1);
147 return page;
148}
149
Denys Vlasenko4b0f3262016-03-17 14:18:24 -0700150static __always_inline int PageTail(struct page *page)
Kirill A. Shutemov0e6d31a2016-01-15 16:51:17 -0800151{
152 return READ_ONCE(page->compound_head) & 1;
153}
154
Denys Vlasenko4b0f3262016-03-17 14:18:24 -0700155static __always_inline int PageCompound(struct page *page)
Kirill A. Shutemov0e6d31a2016-01-15 16:51:17 -0800156{
157 return test_bit(PG_head, &page->flags) || PageTail(page);
158}
159
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160/*
Kirill A. Shutemov95ad9752016-01-15 16:51:21 -0800161 * Page flags policies wrt compound pages
162 *
163 * PF_ANY:
164 * the page flag is relevant for small, head and tail pages.
165 *
166 * PF_HEAD:
167 * for compound page all operations related to the page flag applied to
168 * head page.
169 *
170 * PF_NO_TAIL:
171 * modifications of the page flag must be done on small or head pages,
172 * checks can be done on tail pages too.
173 *
174 * PF_NO_COMPOUND:
175 * the page flag is not relevant for compound pages.
176 */
177#define PF_ANY(page, enforce) page
178#define PF_HEAD(page, enforce) compound_head(page)
179#define PF_NO_TAIL(page, enforce) ({ \
180 VM_BUG_ON_PGFLAGS(enforce && PageTail(page), page); \
181 compound_head(page);})
Kirill A. Shutemov822cdd112016-01-15 16:52:03 -0800182#define PF_NO_COMPOUND(page, enforce) ({ \
Kirill A. Shutemov95ad9752016-01-15 16:51:21 -0800183 VM_BUG_ON_PGFLAGS(enforce && PageCompound(page), page); \
184 page;})
185
186/*
Christoph Lameterf94a62e2008-04-28 02:12:49 -0700187 * Macros to create function definitions for page flags
188 */
Kirill A. Shutemov95ad9752016-01-15 16:51:21 -0800189#define TESTPAGEFLAG(uname, lname, policy) \
Denys Vlasenko4b0f3262016-03-17 14:18:24 -0700190static __always_inline int Page##uname(struct page *page) \
Kirill A. Shutemov95ad9752016-01-15 16:51:21 -0800191 { return test_bit(PG_##lname, &policy(page, 0)->flags); }
Christoph Lameterf94a62e2008-04-28 02:12:49 -0700192
Kirill A. Shutemov95ad9752016-01-15 16:51:21 -0800193#define SETPAGEFLAG(uname, lname, policy) \
Denys Vlasenko4b0f3262016-03-17 14:18:24 -0700194static __always_inline void SetPage##uname(struct page *page) \
Kirill A. Shutemov95ad9752016-01-15 16:51:21 -0800195 { set_bit(PG_##lname, &policy(page, 1)->flags); }
Christoph Lameterf94a62e2008-04-28 02:12:49 -0700196
Kirill A. Shutemov95ad9752016-01-15 16:51:21 -0800197#define CLEARPAGEFLAG(uname, lname, policy) \
Denys Vlasenko4b0f3262016-03-17 14:18:24 -0700198static __always_inline void ClearPage##uname(struct page *page) \
Kirill A. Shutemov95ad9752016-01-15 16:51:21 -0800199 { clear_bit(PG_##lname, &policy(page, 1)->flags); }
Christoph Lameterf94a62e2008-04-28 02:12:49 -0700200
Kirill A. Shutemov95ad9752016-01-15 16:51:21 -0800201#define __SETPAGEFLAG(uname, lname, policy) \
Denys Vlasenko4b0f3262016-03-17 14:18:24 -0700202static __always_inline void __SetPage##uname(struct page *page) \
Kirill A. Shutemov95ad9752016-01-15 16:51:21 -0800203 { __set_bit(PG_##lname, &policy(page, 1)->flags); }
Christoph Lameterf94a62e2008-04-28 02:12:49 -0700204
Kirill A. Shutemov95ad9752016-01-15 16:51:21 -0800205#define __CLEARPAGEFLAG(uname, lname, policy) \
Denys Vlasenko4b0f3262016-03-17 14:18:24 -0700206static __always_inline void __ClearPage##uname(struct page *page) \
Kirill A. Shutemov95ad9752016-01-15 16:51:21 -0800207 { __clear_bit(PG_##lname, &policy(page, 1)->flags); }
Christoph Lameterf94a62e2008-04-28 02:12:49 -0700208
Kirill A. Shutemov95ad9752016-01-15 16:51:21 -0800209#define TESTSETFLAG(uname, lname, policy) \
Denys Vlasenko4b0f3262016-03-17 14:18:24 -0700210static __always_inline int TestSetPage##uname(struct page *page) \
Kirill A. Shutemov95ad9752016-01-15 16:51:21 -0800211 { return test_and_set_bit(PG_##lname, &policy(page, 1)->flags); }
Christoph Lameterf94a62e2008-04-28 02:12:49 -0700212
Kirill A. Shutemov95ad9752016-01-15 16:51:21 -0800213#define TESTCLEARFLAG(uname, lname, policy) \
Denys Vlasenko4b0f3262016-03-17 14:18:24 -0700214static __always_inline int TestClearPage##uname(struct page *page) \
Kirill A. Shutemov95ad9752016-01-15 16:51:21 -0800215 { return test_and_clear_bit(PG_##lname, &policy(page, 1)->flags); }
Christoph Lameterf94a62e2008-04-28 02:12:49 -0700216
Kirill A. Shutemov95ad9752016-01-15 16:51:21 -0800217#define PAGEFLAG(uname, lname, policy) \
218 TESTPAGEFLAG(uname, lname, policy) \
219 SETPAGEFLAG(uname, lname, policy) \
220 CLEARPAGEFLAG(uname, lname, policy)
Christoph Lameterf94a62e2008-04-28 02:12:49 -0700221
Kirill A. Shutemov95ad9752016-01-15 16:51:21 -0800222#define __PAGEFLAG(uname, lname, policy) \
223 TESTPAGEFLAG(uname, lname, policy) \
224 __SETPAGEFLAG(uname, lname, policy) \
225 __CLEARPAGEFLAG(uname, lname, policy)
Christoph Lameterf94a62e2008-04-28 02:12:49 -0700226
Kirill A. Shutemov95ad9752016-01-15 16:51:21 -0800227#define TESTSCFLAG(uname, lname, policy) \
228 TESTSETFLAG(uname, lname, policy) \
229 TESTCLEARFLAG(uname, lname, policy)
Christoph Lameterf94a62e2008-04-28 02:12:49 -0700230
Johannes Weiner2f3e4422014-08-06 16:05:40 -0700231#define TESTPAGEFLAG_FALSE(uname) \
232static inline int Page##uname(const struct page *page) { return 0; }
233
Lee Schermerhorn8a7a8542008-10-18 20:26:37 -0700234#define SETPAGEFLAG_NOOP(uname) \
235static inline void SetPage##uname(struct page *page) { }
236
237#define CLEARPAGEFLAG_NOOP(uname) \
238static inline void ClearPage##uname(struct page *page) { }
239
240#define __CLEARPAGEFLAG_NOOP(uname) \
241static inline void __ClearPage##uname(struct page *page) { }
242
Johannes Weiner2f3e4422014-08-06 16:05:40 -0700243#define TESTSETFLAG_FALSE(uname) \
244static inline int TestSetPage##uname(struct page *page) { return 0; }
245
Lee Schermerhorn8a7a8542008-10-18 20:26:37 -0700246#define TESTCLEARFLAG_FALSE(uname) \
247static inline int TestClearPage##uname(struct page *page) { return 0; }
248
Johannes Weiner2f3e4422014-08-06 16:05:40 -0700249#define PAGEFLAG_FALSE(uname) TESTPAGEFLAG_FALSE(uname) \
250 SETPAGEFLAG_NOOP(uname) CLEARPAGEFLAG_NOOP(uname)
251
252#define TESTSCFLAG_FALSE(uname) \
253 TESTSETFLAG_FALSE(uname) TESTCLEARFLAG_FALSE(uname)
254
Kirill A. Shutemov48c935a2016-01-15 16:51:24 -0800255__PAGEFLAG(Locked, locked, PF_NO_TAIL)
Kirill A. Shutemovdf8c94d2016-01-15 16:51:28 -0800256PAGEFLAG(Error, error, PF_NO_COMPOUND) TESTCLEARFLAG(Error, error, PF_NO_COMPOUND)
Kirill A. Shutemov8cb38fa2016-01-15 16:51:32 -0800257PAGEFLAG(Referenced, referenced, PF_HEAD)
258 TESTCLEARFLAG(Referenced, referenced, PF_HEAD)
259 __SETPAGEFLAG(Referenced, referenced, PF_HEAD)
Kirill A. Shutemovdf8c94d2016-01-15 16:51:28 -0800260PAGEFLAG(Dirty, dirty, PF_HEAD) TESTSCFLAG(Dirty, dirty, PF_HEAD)
261 __CLEARPAGEFLAG(Dirty, dirty, PF_HEAD)
Kirill A. Shutemov8cb38fa2016-01-15 16:51:32 -0800262PAGEFLAG(LRU, lru, PF_HEAD) __CLEARPAGEFLAG(LRU, lru, PF_HEAD)
263PAGEFLAG(Active, active, PF_HEAD) __CLEARPAGEFLAG(Active, active, PF_HEAD)
264 TESTCLEARFLAG(Active, active, PF_HEAD)
Kirill A. Shutemovdcb351c2016-01-15 16:51:35 -0800265__PAGEFLAG(Slab, slab, PF_NO_TAIL)
266__PAGEFLAG(SlobFree, slob_free, PF_NO_TAIL)
Kirill A. Shutemovdf8c94d2016-01-15 16:51:28 -0800267PAGEFLAG(Checked, checked, PF_NO_COMPOUND) /* Used by some filesystems */
Kirill A. Shutemovc13985f2016-01-15 16:51:39 -0800268
269/* Xen */
270PAGEFLAG(Pinned, pinned, PF_NO_COMPOUND)
271 TESTSCFLAG(Pinned, pinned, PF_NO_COMPOUND)
272PAGEFLAG(SavePinned, savepinned, PF_NO_COMPOUND);
273PAGEFLAG(Foreign, foreign, PF_NO_COMPOUND);
274
Kirill A. Shutemovde09d312016-01-15 16:51:42 -0800275PAGEFLAG(Reserved, reserved, PF_NO_COMPOUND)
276 __CLEARPAGEFLAG(Reserved, reserved, PF_NO_COMPOUND)
Kirill A. Shutemovda5efc42016-01-15 16:51:46 -0800277PAGEFLAG(SwapBacked, swapbacked, PF_NO_TAIL)
278 __CLEARPAGEFLAG(SwapBacked, swapbacked, PF_NO_TAIL)
279 __SETPAGEFLAG(SwapBacked, swapbacked, PF_NO_TAIL)
Christoph Lameter6a1e7f72008-04-28 02:12:50 -0700280
Christoph Lameterf94a62e2008-04-28 02:12:49 -0700281/*
David Howells266cf652009-04-03 16:42:36 +0100282 * Private page markings that may be used by the filesystem that owns the page
283 * for its own purposes.
284 * - PG_private and PG_private_2 cause releasepage() and co to be invoked
285 */
Kirill A. Shutemov95ad9752016-01-15 16:51:21 -0800286PAGEFLAG(Private, private, PF_ANY) __SETPAGEFLAG(Private, private, PF_ANY)
287 __CLEARPAGEFLAG(Private, private, PF_ANY)
288PAGEFLAG(Private2, private_2, PF_ANY) TESTSCFLAG(Private2, private_2, PF_ANY)
289PAGEFLAG(OwnerPriv1, owner_priv_1, PF_ANY)
290 TESTCLEARFLAG(OwnerPriv1, owner_priv_1, PF_ANY)
David Howells266cf652009-04-03 16:42:36 +0100291
292/*
Christoph Lameter6a1e7f72008-04-28 02:12:50 -0700293 * Only test-and-set exist for PG_writeback. The unconditional operators are
294 * risky: they bypass page accounting.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700295 */
Kirill A. Shutemovdf8c94d2016-01-15 16:51:28 -0800296TESTPAGEFLAG(Writeback, writeback, PF_NO_COMPOUND)
297 TESTSCFLAG(Writeback, writeback, PF_NO_COMPOUND)
Kirill A. Shutemove2f0a0d2016-07-26 15:25:59 -0700298PAGEFLAG(MappedToDisk, mappedtodisk, PF_NO_TAIL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299
Shaohua Li579f8292014-02-06 12:04:21 -0800300/* PG_readahead is only used for reads; PG_reclaim is only for writes */
Kirill A. Shutemove2f0a0d2016-07-26 15:25:59 -0700301PAGEFLAG(Reclaim, reclaim, PF_NO_TAIL)
302 TESTCLEARFLAG(Reclaim, reclaim, PF_NO_TAIL)
Kirill A. Shutemovdf8c94d2016-01-15 16:51:28 -0800303PAGEFLAG(Readahead, reclaim, PF_NO_COMPOUND)
304 TESTCLEARFLAG(Readahead, reclaim, PF_NO_COMPOUND)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700305
Christoph Lameter6a1e7f72008-04-28 02:12:50 -0700306#ifdef CONFIG_HIGHMEM
307/*
308 * Must use a macro here due to header dependency issues. page_zone() is not
309 * available at this point.
310 */
Vineet Gupta3ca65c12015-11-05 18:48:29 -0800311#define PageHighMem(__p) is_highmem_idx(page_zonenum(__p))
Christoph Lameter6a1e7f72008-04-28 02:12:50 -0700312#else
Christoph Lameterec7cade2008-04-28 02:12:53 -0700313PAGEFLAG_FALSE(HighMem)
Christoph Lameter6a1e7f72008-04-28 02:12:50 -0700314#endif
315
316#ifdef CONFIG_SWAP
Kirill A. Shutemov50ea78d2016-01-15 16:51:49 -0800317PAGEFLAG(SwapCache, swapcache, PF_NO_COMPOUND)
Christoph Lameter6a1e7f72008-04-28 02:12:50 -0700318#else
Christoph Lameterec7cade2008-04-28 02:12:53 -0700319PAGEFLAG_FALSE(SwapCache)
Christoph Lameter6a1e7f72008-04-28 02:12:50 -0700320#endif
321
Kirill A. Shutemov8cb38fa2016-01-15 16:51:32 -0800322PAGEFLAG(Unevictable, unevictable, PF_HEAD)
323 __CLEARPAGEFLAG(Unevictable, unevictable, PF_HEAD)
324 TESTCLEARFLAG(Unevictable, unevictable, PF_HEAD)
Lee Schermerhorn894bc312008-10-18 20:26:39 -0700325
Hugh Dickinsaf8e3352009-12-14 17:58:59 -0800326#ifdef CONFIG_MMU
Kirill A. Shutemove4f87d52016-01-15 16:51:53 -0800327PAGEFLAG(Mlocked, mlocked, PF_NO_TAIL)
328 __CLEARPAGEFLAG(Mlocked, mlocked, PF_NO_TAIL)
329 TESTSCFLAG(Mlocked, mlocked, PF_NO_TAIL)
David Howells33925b22009-03-31 15:23:26 -0700330#else
Johannes Weiner2f3e4422014-08-06 16:05:40 -0700331PAGEFLAG_FALSE(Mlocked) __CLEARPAGEFLAG_NOOP(Mlocked)
Kirill A. Shutemov685eaad2016-01-15 16:52:10 -0800332 TESTSCFLAG_FALSE(Mlocked)
David Howells33925b22009-03-31 15:23:26 -0700333#endif
334
Venkatesh Pallipadi46cf98c2009-07-10 09:57:37 -0700335#ifdef CONFIG_ARCH_USES_PG_UNCACHED
Kirill A. Shutemovb9d41812016-01-15 16:51:56 -0800336PAGEFLAG(Uncached, uncached, PF_NO_COMPOUND)
Christoph Lameter602c4d12008-04-28 02:12:52 -0700337#else
Christoph Lameterec7cade2008-04-28 02:12:53 -0700338PAGEFLAG_FALSE(Uncached)
Christoph Lameter6a1e7f72008-04-28 02:12:50 -0700339#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340
Andi Kleend466f2f2009-09-16 11:50:03 +0200341#ifdef CONFIG_MEMORY_FAILURE
Kirill A. Shutemov95ad9752016-01-15 16:51:21 -0800342PAGEFLAG(HWPoison, hwpoison, PF_ANY)
343TESTSCFLAG(HWPoison, hwpoison, PF_ANY)
Andi Kleend466f2f2009-09-16 11:50:03 +0200344#define __PG_HWPOISON (1UL << PG_hwpoison)
345#else
346PAGEFLAG_FALSE(HWPoison)
347#define __PG_HWPOISON 0
348#endif
349
Vladimir Davydov33c3fc72015-09-09 15:35:45 -0700350#if defined(CONFIG_IDLE_PAGE_TRACKING) && defined(CONFIG_64BIT)
Kirill A. Shutemov95ad9752016-01-15 16:51:21 -0800351TESTPAGEFLAG(Young, young, PF_ANY)
352SETPAGEFLAG(Young, young, PF_ANY)
353TESTCLEARFLAG(Young, young, PF_ANY)
354PAGEFLAG(Idle, idle, PF_ANY)
Vladimir Davydov33c3fc72015-09-09 15:35:45 -0700355#endif
356
Kirill A. Shutemove8c61582015-04-15 16:13:08 -0700357/*
358 * On an anonymous page mapped into a user virtual memory area,
359 * page->mapping points to its anon_vma, not to a struct address_space;
360 * with the PAGE_MAPPING_ANON bit set to distinguish it. See rmap.h.
361 *
362 * On an anonymous page in a VM_MERGEABLE area, if CONFIG_KSM is enabled,
Minchan Kimbda807d2016-07-26 15:23:05 -0700363 * the PAGE_MAPPING_MOVABLE bit may be set along with the PAGE_MAPPING_ANON
364 * bit; and then page->mapping points, not to an anon_vma, but to a private
Kirill A. Shutemove8c61582015-04-15 16:13:08 -0700365 * structure which KSM associates with that merged page. See ksm.h.
366 *
Minchan Kimbda807d2016-07-26 15:23:05 -0700367 * PAGE_MAPPING_KSM without PAGE_MAPPING_ANON is used for non-lru movable
368 * page and then page->mapping points a struct address_space.
Kirill A. Shutemove8c61582015-04-15 16:13:08 -0700369 *
370 * Please note that, confusingly, "page_mapping" refers to the inode
371 * address_space which maps the page from disk; whereas "page_mapped"
372 * refers to user virtual address space into which the page is mapped.
373 */
Minchan Kimbda807d2016-07-26 15:23:05 -0700374#define PAGE_MAPPING_ANON 0x1
375#define PAGE_MAPPING_MOVABLE 0x2
376#define PAGE_MAPPING_KSM (PAGE_MAPPING_ANON | PAGE_MAPPING_MOVABLE)
377#define PAGE_MAPPING_FLAGS (PAGE_MAPPING_ANON | PAGE_MAPPING_MOVABLE)
Kirill A. Shutemove8c61582015-04-15 16:13:08 -0700378
Minchan Kimbda807d2016-07-26 15:23:05 -0700379static __always_inline int PageMappingFlags(struct page *page)
Mel Gorman17514572016-05-19 17:13:21 -0700380{
Minchan Kimbda807d2016-07-26 15:23:05 -0700381 return ((unsigned long)page->mapping & PAGE_MAPPING_FLAGS) != 0;
Mel Gorman17514572016-05-19 17:13:21 -0700382}
383
Denys Vlasenko4b0f3262016-03-17 14:18:24 -0700384static __always_inline int PageAnon(struct page *page)
Kirill A. Shutemove8c61582015-04-15 16:13:08 -0700385{
Kirill A. Shutemov822cdd112016-01-15 16:52:03 -0800386 page = compound_head(page);
Minchan Kimbda807d2016-07-26 15:23:05 -0700387 return ((unsigned long)page->mapping & PAGE_MAPPING_ANON) != 0;
388}
389
390static __always_inline int __PageMovable(struct page *page)
391{
392 return ((unsigned long)page->mapping & PAGE_MAPPING_FLAGS) ==
393 PAGE_MAPPING_MOVABLE;
Kirill A. Shutemove8c61582015-04-15 16:13:08 -0700394}
395
396#ifdef CONFIG_KSM
397/*
398 * A KSM page is one of those write-protected "shared pages" or "merged pages"
399 * which KSM maps into multiple mms, wherever identical anonymous page content
400 * is found in VM_MERGEABLE vmas. It's a PageAnon page, pointing not to any
401 * anon_vma, but to that page's node of the stable tree.
402 */
Denys Vlasenko4b0f3262016-03-17 14:18:24 -0700403static __always_inline int PageKsm(struct page *page)
Kirill A. Shutemove8c61582015-04-15 16:13:08 -0700404{
Kirill A. Shutemov822cdd112016-01-15 16:52:03 -0800405 page = compound_head(page);
Kirill A. Shutemove8c61582015-04-15 16:13:08 -0700406 return ((unsigned long)page->mapping & PAGE_MAPPING_FLAGS) ==
Minchan Kimbda807d2016-07-26 15:23:05 -0700407 PAGE_MAPPING_KSM;
Kirill A. Shutemove8c61582015-04-15 16:13:08 -0700408}
409#else
410TESTPAGEFLAG_FALSE(Ksm)
411#endif
412
Wu Fengguang1a9b5b72009-12-16 12:19:59 +0100413u64 stable_page_flags(struct page *page);
414
Nick Piggin0ed361d2008-02-04 22:29:34 -0800415static inline int PageUptodate(struct page *page)
416{
Kirill A. Shutemovd2998c42016-01-15 16:52:00 -0800417 int ret;
418 page = compound_head(page);
419 ret = test_bit(PG_uptodate, &(page)->flags);
Nick Piggin0ed361d2008-02-04 22:29:34 -0800420 /*
421 * Must ensure that the data we read out of the page is loaded
422 * _after_ we've loaded page->flags to check for PageUptodate.
423 * We can skip the barrier if the page is not uptodate, because
424 * we wouldn't be reading anything from it.
425 *
426 * See SetPageUptodate() for the other side of the story.
427 */
428 if (ret)
429 smp_rmb();
430
431 return ret;
432}
433
Denys Vlasenko4b0f3262016-03-17 14:18:24 -0700434static __always_inline void __SetPageUptodate(struct page *page)
Nick Piggin0ed361d2008-02-04 22:29:34 -0800435{
Kirill A. Shutemovd2998c42016-01-15 16:52:00 -0800436 VM_BUG_ON_PAGE(PageTail(page), page);
Nick Piggin0ed361d2008-02-04 22:29:34 -0800437 smp_wmb();
Kirill A. Shutemovdf8c94d2016-01-15 16:51:28 -0800438 __set_bit(PG_uptodate, &page->flags);
Nick Piggin0ed361d2008-02-04 22:29:34 -0800439}
440
Denys Vlasenko4b0f3262016-03-17 14:18:24 -0700441static __always_inline void SetPageUptodate(struct page *page)
Heiko Carstens2dcea572006-09-29 01:58:41 -0700442{
Kirill A. Shutemovd2998c42016-01-15 16:52:00 -0800443 VM_BUG_ON_PAGE(PageTail(page), page);
Nick Piggin0ed361d2008-02-04 22:29:34 -0800444 /*
445 * Memory barrier must be issued before setting the PG_uptodate bit,
446 * so that all previous stores issued in order to bring the page
447 * uptodate are actually visible before PageUptodate becomes true.
Nick Piggin0ed361d2008-02-04 22:29:34 -0800448 */
449 smp_wmb();
Kirill A. Shutemovdf8c94d2016-01-15 16:51:28 -0800450 set_bit(PG_uptodate, &page->flags);
Nick Piggin0ed361d2008-02-04 22:29:34 -0800451}
452
Kirill A. Shutemovd2998c42016-01-15 16:52:00 -0800453CLEARPAGEFLAG(Uptodate, uptodate, PF_NO_TAIL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700454
Linus Torvalds1da177e2005-04-16 15:20:36 -0700455int test_clear_page_writeback(struct page *page);
Namjae Jeon1c8349a2014-05-12 08:12:25 -0400456int __test_set_page_writeback(struct page *page, bool keep_write);
457
458#define test_set_page_writeback(page) \
459 __test_set_page_writeback(page, false)
460#define test_set_page_writeback_keepwrite(page) \
461 __test_set_page_writeback(page, true)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700462
Linus Torvalds1da177e2005-04-16 15:20:36 -0700463static inline void set_page_writeback(struct page *page)
464{
465 test_set_page_writeback(page);
466}
467
Namjae Jeon1c8349a2014-05-12 08:12:25 -0400468static inline void set_page_writeback_keepwrite(struct page *page)
469{
470 test_set_page_writeback_keepwrite(page);
471}
472
Kirill A. Shutemov95ad9752016-01-15 16:51:21 -0800473__PAGEFLAG(Head, head, PF_ANY) CLEARPAGEFLAG(Head, head, PF_ANY)
Kirill A. Shutemov1d798ca2015-11-06 16:29:54 -0800474
Denys Vlasenko4b0f3262016-03-17 14:18:24 -0700475static __always_inline void set_compound_head(struct page *page, struct page *head)
Kirill A. Shutemov1d798ca2015-11-06 16:29:54 -0800476{
477 WRITE_ONCE(page->compound_head, (unsigned long)head + 1);
478}
479
Denys Vlasenko4b0f3262016-03-17 14:18:24 -0700480static __always_inline void clear_compound_head(struct page *page)
Kirill A. Shutemov1d798ca2015-11-06 16:29:54 -0800481{
482 WRITE_ONCE(page->compound_head, 0);
483}
484
Andrea Arcangeli4e6af672011-01-13 15:46:44 -0800485#ifdef CONFIG_TRANSPARENT_HUGEPAGE
486static inline void ClearPageCompound(struct page *page)
487{
488 BUG_ON(!PageHead(page));
489 ClearPageHead(page);
490}
491#endif
Petr Tesarikb3acc562014-06-23 13:22:03 -0700492
Yu Zhaod2a1a1f2016-05-20 16:58:16 -0700493#define PG_head_mask ((1UL << PG_head))
Petr Tesarikb3acc562014-06-23 13:22:03 -0700494
Kirill A. Shutemove8c61582015-04-15 16:13:08 -0700495#ifdef CONFIG_HUGETLB_PAGE
496int PageHuge(struct page *page);
497int PageHeadHuge(struct page *page);
Naoya Horiguchi7e1f0492015-04-15 16:14:41 -0700498bool page_huge_active(struct page *page);
Kirill A. Shutemove8c61582015-04-15 16:13:08 -0700499#else
500TESTPAGEFLAG_FALSE(Huge)
501TESTPAGEFLAG_FALSE(HeadHuge)
Naoya Horiguchi7e1f0492015-04-15 16:14:41 -0700502
503static inline bool page_huge_active(struct page *page)
504{
505 return 0;
506}
Kirill A. Shutemove8c61582015-04-15 16:13:08 -0700507#endif
508
Naoya Horiguchi7e1f0492015-04-15 16:14:41 -0700509
Andrea Arcangeli936a5fe2011-01-13 15:46:48 -0800510#ifdef CONFIG_TRANSPARENT_HUGEPAGE
Andrea Arcangeli71e3aac2011-01-13 15:46:52 -0800511/*
512 * PageHuge() only returns true for hugetlbfs pages, but not for
513 * normal or transparent huge pages.
514 *
515 * PageTransHuge() returns true for both transparent huge and
516 * hugetlbfs pages, but not normal pages. PageTransHuge() can only be
517 * called only in the core VM paths where hugetlbfs pages can't exist.
518 */
519static inline int PageTransHuge(struct page *page)
520{
Sasha Levin309381fea2014-01-23 15:52:54 -0800521 VM_BUG_ON_PAGE(PageTail(page), page);
Andrea Arcangeli71e3aac2011-01-13 15:46:52 -0800522 return PageHead(page);
523}
524
Dean Nelson385de352012-03-21 16:34:05 -0700525/*
526 * PageTransCompound returns true for both transparent huge pages
527 * and hugetlbfs pages, so it should only be called when it's known
528 * that hugetlbfs pages aren't involved.
529 */
Andrea Arcangeli936a5fe2011-01-13 15:46:48 -0800530static inline int PageTransCompound(struct page *page)
531{
532 return PageCompound(page);
533}
Andrea Arcangeli71e3aac2011-01-13 15:46:52 -0800534
Dean Nelson385de352012-03-21 16:34:05 -0700535/*
Andrea Arcangeli127393f2016-05-05 16:22:20 -0700536 * PageTransCompoundMap is the same as PageTransCompound, but it also
537 * guarantees the primary MMU has the entire compound page mapped
538 * through pmd_trans_huge, which in turn guarantees the secondary MMUs
539 * can also map the entire compound page. This allows the secondary
540 * MMUs to call get_user_pages() only once for each compound page and
541 * to immediately map the entire compound page with a single secondary
542 * MMU fault. If there will be a pmd split later, the secondary MMUs
543 * will get an update through the MMU notifier invalidation through
544 * split_huge_pmd().
545 *
546 * Unlike PageTransCompound, this is safe to be called only while
547 * split_huge_pmd() cannot run from under us, like if protected by the
548 * MMU notifier, otherwise it may result in page->_mapcount < 0 false
549 * positives.
550 */
551static inline int PageTransCompoundMap(struct page *page)
552{
553 return PageTransCompound(page) && atomic_read(&page->_mapcount) < 0;
554}
555
556/*
Dean Nelson385de352012-03-21 16:34:05 -0700557 * PageTransTail returns true for both transparent huge pages
558 * and hugetlbfs pages, so it should only be called when it's known
559 * that hugetlbfs pages aren't involved.
560 */
561static inline int PageTransTail(struct page *page)
562{
563 return PageTail(page);
564}
565
Kirill A. Shutemov53f92632016-01-15 16:53:42 -0800566/*
567 * PageDoubleMap indicates that the compound page is mapped with PTEs as well
568 * as PMDs.
569 *
570 * This is required for optimization of rmap operations for THP: we can postpone
571 * per small page mapcount accounting (and its overhead from atomic operations)
572 * until the first PMD split.
573 *
574 * For the page PageDoubleMap means ->_mapcount in all sub-pages is offset up
575 * by one. This reference will go away with last compound_mapcount.
576 *
577 * See also __split_huge_pmd_locked() and page_remove_anon_compound_rmap().
578 */
579static inline int PageDoubleMap(struct page *page)
580{
581 return PageHead(page) && test_bit(PG_double_map, &page[1].flags);
582}
583
Kirill A. Shutemov9a73f612016-07-26 15:25:53 -0700584static inline void SetPageDoubleMap(struct page *page)
585{
586 VM_BUG_ON_PAGE(!PageHead(page), page);
587 set_bit(PG_double_map, &page[1].flags);
588}
589
590static inline void ClearPageDoubleMap(struct page *page)
591{
592 VM_BUG_ON_PAGE(!PageHead(page), page);
593 clear_bit(PG_double_map, &page[1].flags);
594}
Kirill A. Shutemov53f92632016-01-15 16:53:42 -0800595static inline int TestSetPageDoubleMap(struct page *page)
596{
597 VM_BUG_ON_PAGE(!PageHead(page), page);
598 return test_and_set_bit(PG_double_map, &page[1].flags);
599}
600
601static inline int TestClearPageDoubleMap(struct page *page)
602{
603 VM_BUG_ON_PAGE(!PageHead(page), page);
604 return test_and_clear_bit(PG_double_map, &page[1].flags);
605}
606
Andrea Arcangeli936a5fe2011-01-13 15:46:48 -0800607#else
Kirill A. Shutemovd8c1bde2016-01-15 16:51:13 -0800608TESTPAGEFLAG_FALSE(TransHuge)
609TESTPAGEFLAG_FALSE(TransCompound)
Andrea Arcangeli127393f2016-05-05 16:22:20 -0700610TESTPAGEFLAG_FALSE(TransCompoundMap)
Kirill A. Shutemovd8c1bde2016-01-15 16:51:13 -0800611TESTPAGEFLAG_FALSE(TransTail)
Kirill A. Shutemov9a73f612016-07-26 15:25:53 -0700612PAGEFLAG_FALSE(DoubleMap)
Kirill A. Shutemov53f92632016-01-15 16:53:42 -0800613 TESTSETFLAG_FALSE(DoubleMap)
614 TESTCLEARFLAG_FALSE(DoubleMap)
Andrea Arcangeli936a5fe2011-01-13 15:46:48 -0800615#endif
616
Mel Gorman072bb0a2012-07-31 16:43:58 -0700617/*
Vladimir Davydov632c0a12016-07-26 15:24:18 -0700618 * For pages that are never mapped to userspace, page->mapcount may be
619 * used for storing extra information about page type. Any value used
620 * for this purpose must be <= -2, but it's better start not too close
621 * to -2 so that an underflow of the page_mapcount() won't be mistaken
622 * for a special page.
623 */
624#define PAGE_MAPCOUNT_OPS(uname, lname) \
625static __always_inline int Page##uname(struct page *page) \
626{ \
627 return atomic_read(&page->_mapcount) == \
628 PAGE_##lname##_MAPCOUNT_VALUE; \
629} \
630static __always_inline void __SetPage##uname(struct page *page) \
631{ \
632 VM_BUG_ON_PAGE(atomic_read(&page->_mapcount) != -1, page); \
633 atomic_set(&page->_mapcount, PAGE_##lname##_MAPCOUNT_VALUE); \
634} \
635static __always_inline void __ClearPage##uname(struct page *page) \
636{ \
637 VM_BUG_ON_PAGE(!Page##uname(page), page); \
638 atomic_set(&page->_mapcount, -1); \
639}
640
641/*
Kirill A. Shutemove8c61582015-04-15 16:13:08 -0700642 * PageBuddy() indicate that the page is free and in the buddy system
643 * (see mm/page_alloc.c).
Kirill A. Shutemove8c61582015-04-15 16:13:08 -0700644 */
Vladimir Davydov632c0a12016-07-26 15:24:18 -0700645#define PAGE_BUDDY_MAPCOUNT_VALUE (-128)
646PAGE_MAPCOUNT_OPS(Buddy, BUDDY)
Kirill A. Shutemove8c61582015-04-15 16:13:08 -0700647
Vladimir Davydov632c0a12016-07-26 15:24:18 -0700648/*
649 * PageBalloon() is set on pages that are on the balloon page list
650 * (see mm/balloon_compaction.c).
651 */
652#define PAGE_BALLOON_MAPCOUNT_VALUE (-256)
653PAGE_MAPCOUNT_OPS(Balloon, BALLOON)
Kirill A. Shutemove8c61582015-04-15 16:13:08 -0700654
Vladimir Davydov49491482016-07-26 15:24:24 -0700655/*
656 * If kmemcg is enabled, the buddy allocator will set PageKmemcg() on
657 * pages allocated with __GFP_ACCOUNT. It gets cleared on page free.
658 */
659#define PAGE_KMEMCG_MAPCOUNT_VALUE (-512)
660PAGE_MAPCOUNT_OPS(Kmemcg, KMEMCG)
661
Naoya Horiguchi832fc1d2016-03-17 14:17:41 -0700662extern bool is_free_buddy_page(struct page *page);
663
Minchan Kimbda807d2016-07-26 15:23:05 -0700664__PAGEFLAG(Isolated, isolated, PF_ANY);
665
Kirill A. Shutemove8c61582015-04-15 16:13:08 -0700666/*
Mel Gorman072bb0a2012-07-31 16:43:58 -0700667 * If network-based swap is enabled, sl*b must keep track of whether pages
668 * were allocated from pfmemalloc reserves.
669 */
670static inline int PageSlabPfmemalloc(struct page *page)
671{
Sasha Levin309381fea2014-01-23 15:52:54 -0800672 VM_BUG_ON_PAGE(!PageSlab(page), page);
Mel Gorman072bb0a2012-07-31 16:43:58 -0700673 return PageActive(page);
674}
675
676static inline void SetPageSlabPfmemalloc(struct page *page)
677{
Sasha Levin309381fea2014-01-23 15:52:54 -0800678 VM_BUG_ON_PAGE(!PageSlab(page), page);
Mel Gorman072bb0a2012-07-31 16:43:58 -0700679 SetPageActive(page);
680}
681
682static inline void __ClearPageSlabPfmemalloc(struct page *page)
683{
Sasha Levin309381fea2014-01-23 15:52:54 -0800684 VM_BUG_ON_PAGE(!PageSlab(page), page);
Mel Gorman072bb0a2012-07-31 16:43:58 -0700685 __ClearPageActive(page);
686}
687
688static inline void ClearPageSlabPfmemalloc(struct page *page)
689{
Sasha Levin309381fea2014-01-23 15:52:54 -0800690 VM_BUG_ON_PAGE(!PageSlab(page), page);
Mel Gorman072bb0a2012-07-31 16:43:58 -0700691 ClearPageActive(page);
692}
693
Hugh Dickinsaf8e3352009-12-14 17:58:59 -0800694#ifdef CONFIG_MMU
Yu Zhaod2a1a1f2016-05-20 16:58:16 -0700695#define __PG_MLOCKED (1UL << PG_mlocked)
David Howells33925b22009-03-31 15:23:26 -0700696#else
Nick Pigginb291f002008-10-18 20:26:44 -0700697#define __PG_MLOCKED 0
Lee Schermerhorn894bc312008-10-18 20:26:39 -0700698#endif
699
Russ Andersondfa7e202008-06-09 11:18:45 -0500700/*
701 * Flags checked when a page is freed. Pages being freed should not have
702 * these flags set. It they are, there is a problem.
703 */
Hugh Dickins79f4b7b2009-01-06 14:40:05 -0800704#define PAGE_FLAGS_CHECK_AT_FREE \
Yu Zhaod2a1a1f2016-05-20 16:58:16 -0700705 (1UL << PG_lru | 1UL << PG_locked | \
706 1UL << PG_private | 1UL << PG_private_2 | \
707 1UL << PG_writeback | 1UL << PG_reserved | \
708 1UL << PG_slab | 1UL << PG_swapcache | 1UL << PG_active | \
709 1UL << PG_unevictable | __PG_MLOCKED)
Russ Andersondfa7e202008-06-09 11:18:45 -0500710
711/*
712 * Flags checked when a page is prepped for return by the page allocator.
Naoya Horiguchif4c18e62015-08-06 15:47:08 -0700713 * Pages being prepped should not have these flags set. It they are set,
Hugh Dickins79f4b7b2009-01-06 14:40:05 -0800714 * there has been a kernel bug or struct page corruption.
Naoya Horiguchif4c18e62015-08-06 15:47:08 -0700715 *
716 * __PG_HWPOISON is exceptional because it needs to be kept beyond page's
717 * alloc-free cycle to prevent from reusing the page.
Russ Andersondfa7e202008-06-09 11:18:45 -0500718 */
Naoya Horiguchif4c18e62015-08-06 15:47:08 -0700719#define PAGE_FLAGS_CHECK_AT_PREP \
Yu Zhaod2a1a1f2016-05-20 16:58:16 -0700720 (((1UL << NR_PAGEFLAGS) - 1) & ~__PG_HWPOISON)
Russ Andersondfa7e202008-06-09 11:18:45 -0500721
Johannes Weineredcf4742009-09-21 17:02:59 -0700722#define PAGE_FLAGS_PRIVATE \
Yu Zhaod2a1a1f2016-05-20 16:58:16 -0700723 (1UL << PG_private | 1UL << PG_private_2)
David Howells266cf652009-04-03 16:42:36 +0100724/**
725 * page_has_private - Determine if page has private stuff
726 * @page: The page to be checked
727 *
728 * Determine if a page has private stuff, indicating that release routines
729 * should be invoked upon it.
730 */
Johannes Weineredcf4742009-09-21 17:02:59 -0700731static inline int page_has_private(struct page *page)
732{
733 return !!(page->flags & PAGE_FLAGS_PRIVATE);
734}
735
Kirill A. Shutemov95ad9752016-01-15 16:51:21 -0800736#undef PF_ANY
737#undef PF_HEAD
738#undef PF_NO_TAIL
739#undef PF_NO_COMPOUND
Johannes Weineredcf4742009-09-21 17:02:59 -0700740#endif /* !__GENERATING_BOUNDS_H */
David Howells266cf652009-04-03 16:42:36 +0100741
Linus Torvalds1da177e2005-04-16 15:20:36 -0700742#endif /* PAGE_FLAGS_H */