Commit | Line | Data |
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b2441318 | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
1da177e4 LT |
2 | /* |
3 | * Macros for manipulating and testing page->flags | |
4 | */ | |
5 | ||
6 | #ifndef PAGE_FLAGS_H | |
7 | #define PAGE_FLAGS_H | |
8 | ||
f886ed44 | 9 | #include <linux/types.h> |
187f1882 | 10 | #include <linux/bug.h> |
072bb0aa | 11 | #include <linux/mmdebug.h> |
9223b419 | 12 | #ifndef __GENERATING_BOUNDS_H |
6d777953 | 13 | #include <linux/mm_types.h> |
01fc0ac1 | 14 | #include <generated/bounds.h> |
9223b419 | 15 | #endif /* !__GENERATING_BOUNDS_H */ |
f886ed44 | 16 | |
1da177e4 LT |
17 | /* |
18 | * Various page->flags bits: | |
19 | * | |
6e2e07cd DH |
20 | * PG_reserved is set for special pages. The "struct page" of such a page |
21 | * should in general not be touched (e.g. set dirty) except by its owner. | |
22 | * Pages marked as PG_reserved include: | |
23 | * - Pages part of the kernel image (including vDSO) and similar (e.g. BIOS, | |
24 | * initrd, HW tables) | |
25 | * - Pages reserved or allocated early during boot (before the page allocator | |
26 | * was initialized). This includes (depending on the architecture) the | |
27 | * initial vmemmap, initial page tables, crashkernel, elfcorehdr, and much | |
28 | * much more. Once (if ever) freed, PG_reserved is cleared and they will | |
29 | * be given to the page allocator. | |
30 | * - Pages falling into physical memory gaps - not IORESOURCE_SYSRAM. Trying | |
31 | * to read/write these pages might end badly. Don't touch! | |
32 | * - The zero page(s) | |
33 | * - Pages not added to the page allocator when onlining a section because | |
34 | * they were excluded via the online_page_callback() or because they are | |
35 | * PG_hwpoison. | |
36 | * - Pages allocated in the context of kexec/kdump (loaded kernel image, | |
37 | * control pages, vmcoreinfo) | |
38 | * - MMIO/DMA pages. Some architectures don't allow to ioremap pages that are | |
39 | * not marked PG_reserved (as they might be in use by somebody else who does | |
40 | * not respect the caching strategy). | |
41 | * - Pages part of an offline section (struct pages of offline sections should | |
42 | * not be trusted as they will be initialized when first onlined). | |
43 | * - MCA pages on ia64 | |
44 | * - Pages holding CPU notes for POWER Firmware Assisted Dump | |
45 | * - Device memory (e.g. PMEM, DAX, HMM) | |
46 | * Some PG_reserved pages will be excluded from the hibernation image. | |
47 | * PG_reserved does in general not hinder anybody from dumping or swapping | |
48 | * and is no longer required for remap_pfn_range(). ioremap might require it. | |
49 | * Consequently, PG_reserved for a page mapped into user space can indicate | |
50 | * the zero page, the vDSO, MMIO pages or device memory. | |
1da177e4 | 51 | * |
da6052f7 NP |
52 | * The PG_private bitflag is set on pagecache pages if they contain filesystem |
53 | * specific data (which is normally at page->private). It can be used by | |
54 | * private allocations for its own usage. | |
1da177e4 | 55 | * |
da6052f7 NP |
56 | * During initiation of disk I/O, PG_locked is set. This bit is set before I/O |
57 | * and cleared when writeback _starts_ or when read _completes_. PG_writeback | |
58 | * is set before writeback starts and cleared when it finishes. | |
59 | * | |
60 | * PG_locked also pins a page in pagecache, and blocks truncation of the file | |
61 | * while it is held. | |
62 | * | |
63 | * page_waitqueue(page) is a wait queue of all tasks waiting for the page | |
64 | * to become unlocked. | |
1da177e4 LT |
65 | * |
66 | * PG_uptodate tells whether the page's contents is valid. When a read | |
67 | * completes, the page becomes uptodate, unless a disk I/O error happened. | |
68 | * | |
da6052f7 NP |
69 | * PG_referenced, PG_reclaim are used for page reclaim for anonymous and |
70 | * file-backed pagecache (see mm/vmscan.c). | |
1da177e4 LT |
71 | * |
72 | * PG_error is set to indicate that an I/O error occurred on this page. | |
73 | * | |
74 | * PG_arch_1 is an architecture specific page state bit. The generic code | |
75 | * guarantees that this bit is cleared for a page when it first is entered into | |
76 | * the page cache. | |
77 | * | |
d466f2fc AK |
78 | * PG_hwpoison indicates that a page got corrupted in hardware and contains |
79 | * data with incorrect ECC bits that triggered a machine check. Accessing is | |
80 | * not safe since it may cause another machine check. Don't touch! | |
1da177e4 LT |
81 | */ |
82 | ||
83 | /* | |
84 | * Don't use the *_dontuse flags. Use the macros. Otherwise you'll break | |
91fc8ab3 AW |
85 | * locked- and dirty-page accounting. |
86 | * | |
87 | * The page flags field is split into two parts, the main flags area | |
88 | * which extends from the low bits upwards, and the fields area which | |
89 | * extends from the high bits downwards. | |
90 | * | |
91 | * | FIELD | ... | FLAGS | | |
9223b419 CL |
92 | * N-1 ^ 0 |
93 | * (NR_PAGEFLAGS) | |
91fc8ab3 | 94 | * |
9223b419 CL |
95 | * The fields area is reserved for fields mapping zone, node (for NUMA) and |
96 | * SPARSEMEM section (for variants of SPARSEMEM that require section ids like | |
97 | * SPARSEMEM_EXTREME with !SPARSEMEM_VMEMMAP). | |
1da177e4 | 98 | */ |
e2683181 CL |
99 | enum pageflags { |
100 | PG_locked, /* Page is locked. Don't touch. */ | |
e2683181 CL |
101 | PG_referenced, |
102 | PG_uptodate, | |
103 | PG_dirty, | |
104 | PG_lru, | |
105 | PG_active, | |
1899ad18 | 106 | PG_workingset, |
b91e1302 | 107 | PG_waiters, /* Page has waiters, check its waitqueue. Must be bit #7 and in the same byte as "PG_locked" */ |
1899ad18 | 108 | PG_error, |
e2683181 CL |
109 | PG_slab, |
110 | PG_owner_priv_1, /* Owner use. If pagecache, fs may use*/ | |
e2683181 CL |
111 | PG_arch_1, |
112 | PG_reserved, | |
113 | PG_private, /* If pagecache, has fs-private data */ | |
266cf658 | 114 | PG_private_2, /* If pagecache, has fs aux data */ |
e2683181 | 115 | PG_writeback, /* Page is under writeback */ |
e20b8cca | 116 | PG_head, /* A head page */ |
e2683181 CL |
117 | PG_mappedtodisk, /* Has blocks allocated on-disk */ |
118 | PG_reclaim, /* To be reclaimed asap */ | |
b2e18538 | 119 | PG_swapbacked, /* Page is backed by RAM/swap */ |
894bc310 | 120 | PG_unevictable, /* Page is "unevictable" */ |
af8e3354 | 121 | #ifdef CONFIG_MMU |
b291f000 | 122 | PG_mlocked, /* Page is vma mlocked */ |
894bc310 | 123 | #endif |
46cf98cd | 124 | #ifdef CONFIG_ARCH_USES_PG_UNCACHED |
602c4d11 | 125 | PG_uncached, /* Page has been mapped as uncached */ |
d466f2fc AK |
126 | #endif |
127 | #ifdef CONFIG_MEMORY_FAILURE | |
128 | PG_hwpoison, /* hardware poisoned page. Don't touch */ | |
e9da73d6 | 129 | #endif |
33c3fc71 VD |
130 | #if defined(CONFIG_IDLE_PAGE_TRACKING) && defined(CONFIG_64BIT) |
131 | PG_young, | |
132 | PG_idle, | |
f886ed44 | 133 | #endif |
0cad47cf AW |
134 | __NR_PAGEFLAGS, |
135 | ||
136 | /* Filesystems */ | |
137 | PG_checked = PG_owner_priv_1, | |
138 | ||
6326fec1 NP |
139 | /* SwapBacked */ |
140 | PG_swapcache = PG_owner_priv_1, /* Swap page: swp_entry_t in private */ | |
141 | ||
266cf658 DH |
142 | /* Two page bits are conscripted by FS-Cache to maintain local caching |
143 | * state. These bits are set on pages belonging to the netfs's inodes | |
144 | * when those inodes are being locally cached. | |
145 | */ | |
146 | PG_fscache = PG_private_2, /* page backed by cache */ | |
147 | ||
0cad47cf | 148 | /* XEN */ |
d8ac3dd4 | 149 | /* Pinned in Xen as a read-only pagetable page. */ |
0cad47cf | 150 | PG_pinned = PG_owner_priv_1, |
d8ac3dd4 | 151 | /* Pinned as part of domain save (see xen_mm_pin_all()). */ |
0cad47cf | 152 | PG_savepinned = PG_dirty, |
d8ac3dd4 JH |
153 | /* Has a grant mapping of another (foreign) domain's page. */ |
154 | PG_foreign = PG_owner_priv_1, | |
8a38082d | 155 | |
9023cb7e | 156 | /* SLOB */ |
9023cb7e | 157 | PG_slob_free = PG_private, |
53f9263b KS |
158 | |
159 | /* Compound pages. Stored in first tail page's flags */ | |
160 | PG_double_map = PG_private_2, | |
bda807d4 MK |
161 | |
162 | /* non-lru isolated movable page */ | |
163 | PG_isolated = PG_reclaim, | |
e2683181 | 164 | }; |
1da177e4 | 165 | |
9223b419 CL |
166 | #ifndef __GENERATING_BOUNDS_H |
167 | ||
0e6d31a7 KS |
168 | struct page; /* forward declaration */ |
169 | ||
170 | static inline struct page *compound_head(struct page *page) | |
171 | { | |
172 | unsigned long head = READ_ONCE(page->compound_head); | |
173 | ||
174 | if (unlikely(head & 1)) | |
175 | return (struct page *) (head - 1); | |
176 | return page; | |
177 | } | |
178 | ||
4b0f3261 | 179 | static __always_inline int PageTail(struct page *page) |
0e6d31a7 KS |
180 | { |
181 | return READ_ONCE(page->compound_head) & 1; | |
182 | } | |
183 | ||
4b0f3261 | 184 | static __always_inline int PageCompound(struct page *page) |
0e6d31a7 KS |
185 | { |
186 | return test_bit(PG_head, &page->flags) || PageTail(page); | |
187 | } | |
188 | ||
f165b378 PT |
189 | #define PAGE_POISON_PATTERN -1l |
190 | static inline int PagePoisoned(const struct page *page) | |
191 | { | |
192 | return page->flags == PAGE_POISON_PATTERN; | |
193 | } | |
194 | ||
f682a97a AD |
195 | #ifdef CONFIG_DEBUG_VM |
196 | void page_init_poison(struct page *page, size_t size); | |
197 | #else | |
198 | static inline void page_init_poison(struct page *page, size_t size) | |
199 | { | |
200 | } | |
201 | #endif | |
202 | ||
95ad9755 KS |
203 | /* |
204 | * Page flags policies wrt compound pages | |
205 | * | |
f165b378 PT |
206 | * PF_POISONED_CHECK |
207 | * check if this struct page poisoned/uninitialized | |
208 | * | |
95ad9755 KS |
209 | * PF_ANY: |
210 | * the page flag is relevant for small, head and tail pages. | |
211 | * | |
212 | * PF_HEAD: | |
213 | * for compound page all operations related to the page flag applied to | |
214 | * head page. | |
215 | * | |
62906027 NP |
216 | * PF_ONLY_HEAD: |
217 | * for compound page, callers only ever operate on the head page. | |
218 | * | |
95ad9755 KS |
219 | * PF_NO_TAIL: |
220 | * modifications of the page flag must be done on small or head pages, | |
221 | * checks can be done on tail pages too. | |
222 | * | |
223 | * PF_NO_COMPOUND: | |
224 | * the page flag is not relevant for compound pages. | |
225 | */ | |
f165b378 PT |
226 | #define PF_POISONED_CHECK(page) ({ \ |
227 | VM_BUG_ON_PGFLAGS(PagePoisoned(page), page); \ | |
228 | page; }) | |
229 | #define PF_ANY(page, enforce) PF_POISONED_CHECK(page) | |
230 | #define PF_HEAD(page, enforce) PF_POISONED_CHECK(compound_head(page)) | |
62906027 NP |
231 | #define PF_ONLY_HEAD(page, enforce) ({ \ |
232 | VM_BUG_ON_PGFLAGS(PageTail(page), page); \ | |
f165b378 | 233 | PF_POISONED_CHECK(page); }) |
95ad9755 KS |
234 | #define PF_NO_TAIL(page, enforce) ({ \ |
235 | VM_BUG_ON_PGFLAGS(enforce && PageTail(page), page); \ | |
f165b378 | 236 | PF_POISONED_CHECK(compound_head(page)); }) |
822cdd11 | 237 | #define PF_NO_COMPOUND(page, enforce) ({ \ |
95ad9755 | 238 | VM_BUG_ON_PGFLAGS(enforce && PageCompound(page), page); \ |
f165b378 | 239 | PF_POISONED_CHECK(page); }) |
95ad9755 | 240 | |
f94a62e9 CL |
241 | /* |
242 | * Macros to create function definitions for page flags | |
243 | */ | |
95ad9755 | 244 | #define TESTPAGEFLAG(uname, lname, policy) \ |
4b0f3261 | 245 | static __always_inline int Page##uname(struct page *page) \ |
95ad9755 | 246 | { return test_bit(PG_##lname, &policy(page, 0)->flags); } |
f94a62e9 | 247 | |
95ad9755 | 248 | #define SETPAGEFLAG(uname, lname, policy) \ |
4b0f3261 | 249 | static __always_inline void SetPage##uname(struct page *page) \ |
95ad9755 | 250 | { set_bit(PG_##lname, &policy(page, 1)->flags); } |
f94a62e9 | 251 | |
95ad9755 | 252 | #define CLEARPAGEFLAG(uname, lname, policy) \ |
4b0f3261 | 253 | static __always_inline void ClearPage##uname(struct page *page) \ |
95ad9755 | 254 | { clear_bit(PG_##lname, &policy(page, 1)->flags); } |
f94a62e9 | 255 | |
95ad9755 | 256 | #define __SETPAGEFLAG(uname, lname, policy) \ |
4b0f3261 | 257 | static __always_inline void __SetPage##uname(struct page *page) \ |
95ad9755 | 258 | { __set_bit(PG_##lname, &policy(page, 1)->flags); } |
f94a62e9 | 259 | |
95ad9755 | 260 | #define __CLEARPAGEFLAG(uname, lname, policy) \ |
4b0f3261 | 261 | static __always_inline void __ClearPage##uname(struct page *page) \ |
95ad9755 | 262 | { __clear_bit(PG_##lname, &policy(page, 1)->flags); } |
f94a62e9 | 263 | |
95ad9755 | 264 | #define TESTSETFLAG(uname, lname, policy) \ |
4b0f3261 | 265 | static __always_inline int TestSetPage##uname(struct page *page) \ |
95ad9755 | 266 | { return test_and_set_bit(PG_##lname, &policy(page, 1)->flags); } |
f94a62e9 | 267 | |
95ad9755 | 268 | #define TESTCLEARFLAG(uname, lname, policy) \ |
4b0f3261 | 269 | static __always_inline int TestClearPage##uname(struct page *page) \ |
95ad9755 | 270 | { return test_and_clear_bit(PG_##lname, &policy(page, 1)->flags); } |
f94a62e9 | 271 | |
95ad9755 KS |
272 | #define PAGEFLAG(uname, lname, policy) \ |
273 | TESTPAGEFLAG(uname, lname, policy) \ | |
274 | SETPAGEFLAG(uname, lname, policy) \ | |
275 | CLEARPAGEFLAG(uname, lname, policy) | |
f94a62e9 | 276 | |
95ad9755 KS |
277 | #define __PAGEFLAG(uname, lname, policy) \ |
278 | TESTPAGEFLAG(uname, lname, policy) \ | |
279 | __SETPAGEFLAG(uname, lname, policy) \ | |
280 | __CLEARPAGEFLAG(uname, lname, policy) | |
f94a62e9 | 281 | |
95ad9755 KS |
282 | #define TESTSCFLAG(uname, lname, policy) \ |
283 | TESTSETFLAG(uname, lname, policy) \ | |
284 | TESTCLEARFLAG(uname, lname, policy) | |
f94a62e9 | 285 | |
2f3e442c JW |
286 | #define TESTPAGEFLAG_FALSE(uname) \ |
287 | static inline int Page##uname(const struct page *page) { return 0; } | |
288 | ||
8a7a8544 LS |
289 | #define SETPAGEFLAG_NOOP(uname) \ |
290 | static inline void SetPage##uname(struct page *page) { } | |
291 | ||
292 | #define CLEARPAGEFLAG_NOOP(uname) \ | |
293 | static inline void ClearPage##uname(struct page *page) { } | |
294 | ||
295 | #define __CLEARPAGEFLAG_NOOP(uname) \ | |
296 | static inline void __ClearPage##uname(struct page *page) { } | |
297 | ||
2f3e442c JW |
298 | #define TESTSETFLAG_FALSE(uname) \ |
299 | static inline int TestSetPage##uname(struct page *page) { return 0; } | |
300 | ||
8a7a8544 LS |
301 | #define TESTCLEARFLAG_FALSE(uname) \ |
302 | static inline int TestClearPage##uname(struct page *page) { return 0; } | |
303 | ||
2f3e442c JW |
304 | #define PAGEFLAG_FALSE(uname) TESTPAGEFLAG_FALSE(uname) \ |
305 | SETPAGEFLAG_NOOP(uname) CLEARPAGEFLAG_NOOP(uname) | |
306 | ||
307 | #define TESTSCFLAG_FALSE(uname) \ | |
308 | TESTSETFLAG_FALSE(uname) TESTCLEARFLAG_FALSE(uname) | |
309 | ||
48c935ad | 310 | __PAGEFLAG(Locked, locked, PF_NO_TAIL) |
62906027 | 311 | PAGEFLAG(Waiters, waiters, PF_ONLY_HEAD) __CLEARPAGEFLAG(Waiters, waiters, PF_ONLY_HEAD) |
df8c94d1 | 312 | PAGEFLAG(Error, error, PF_NO_COMPOUND) TESTCLEARFLAG(Error, error, PF_NO_COMPOUND) |
8cb38fab KS |
313 | PAGEFLAG(Referenced, referenced, PF_HEAD) |
314 | TESTCLEARFLAG(Referenced, referenced, PF_HEAD) | |
315 | __SETPAGEFLAG(Referenced, referenced, PF_HEAD) | |
df8c94d1 KS |
316 | PAGEFLAG(Dirty, dirty, PF_HEAD) TESTSCFLAG(Dirty, dirty, PF_HEAD) |
317 | __CLEARPAGEFLAG(Dirty, dirty, PF_HEAD) | |
8cb38fab KS |
318 | PAGEFLAG(LRU, lru, PF_HEAD) __CLEARPAGEFLAG(LRU, lru, PF_HEAD) |
319 | PAGEFLAG(Active, active, PF_HEAD) __CLEARPAGEFLAG(Active, active, PF_HEAD) | |
320 | TESTCLEARFLAG(Active, active, PF_HEAD) | |
1899ad18 JW |
321 | PAGEFLAG(Workingset, workingset, PF_HEAD) |
322 | TESTCLEARFLAG(Workingset, workingset, PF_HEAD) | |
dcb351cd KS |
323 | __PAGEFLAG(Slab, slab, PF_NO_TAIL) |
324 | __PAGEFLAG(SlobFree, slob_free, PF_NO_TAIL) | |
df8c94d1 | 325 | PAGEFLAG(Checked, checked, PF_NO_COMPOUND) /* Used by some filesystems */ |
c13985fa KS |
326 | |
327 | /* Xen */ | |
328 | PAGEFLAG(Pinned, pinned, PF_NO_COMPOUND) | |
329 | TESTSCFLAG(Pinned, pinned, PF_NO_COMPOUND) | |
330 | PAGEFLAG(SavePinned, savepinned, PF_NO_COMPOUND); | |
331 | PAGEFLAG(Foreign, foreign, PF_NO_COMPOUND); | |
332 | ||
de09d31d KS |
333 | PAGEFLAG(Reserved, reserved, PF_NO_COMPOUND) |
334 | __CLEARPAGEFLAG(Reserved, reserved, PF_NO_COMPOUND) | |
d483da5b | 335 | __SETPAGEFLAG(Reserved, reserved, PF_NO_COMPOUND) |
da5efc40 KS |
336 | PAGEFLAG(SwapBacked, swapbacked, PF_NO_TAIL) |
337 | __CLEARPAGEFLAG(SwapBacked, swapbacked, PF_NO_TAIL) | |
338 | __SETPAGEFLAG(SwapBacked, swapbacked, PF_NO_TAIL) | |
95ad9755 | 339 | |
266cf658 DH |
340 | /* |
341 | * Private page markings that may be used by the filesystem that owns the page | |
342 | * for its own purposes. | |
343 | * - PG_private and PG_private_2 cause releasepage() and co to be invoked | |
344 | */ | |
95ad9755 KS |
345 | PAGEFLAG(Private, private, PF_ANY) __SETPAGEFLAG(Private, private, PF_ANY) |
346 | __CLEARPAGEFLAG(Private, private, PF_ANY) | |
347 | PAGEFLAG(Private2, private_2, PF_ANY) TESTSCFLAG(Private2, private_2, PF_ANY) | |
348 | PAGEFLAG(OwnerPriv1, owner_priv_1, PF_ANY) | |
349 | TESTCLEARFLAG(OwnerPriv1, owner_priv_1, PF_ANY) | |
266cf658 | 350 | |
6a1e7f77 CL |
351 | /* |
352 | * Only test-and-set exist for PG_writeback. The unconditional operators are | |
353 | * risky: they bypass page accounting. | |
354 | */ | |
225311a4 HY |
355 | TESTPAGEFLAG(Writeback, writeback, PF_NO_TAIL) |
356 | TESTSCFLAG(Writeback, writeback, PF_NO_TAIL) | |
e2f0a0db | 357 | PAGEFLAG(MappedToDisk, mappedtodisk, PF_NO_TAIL) |
6a1e7f77 | 358 | |
579f8290 | 359 | /* PG_readahead is only used for reads; PG_reclaim is only for writes */ |
e2f0a0db KS |
360 | PAGEFLAG(Reclaim, reclaim, PF_NO_TAIL) |
361 | TESTCLEARFLAG(Reclaim, reclaim, PF_NO_TAIL) | |
df8c94d1 KS |
362 | PAGEFLAG(Readahead, reclaim, PF_NO_COMPOUND) |
363 | TESTCLEARFLAG(Readahead, reclaim, PF_NO_COMPOUND) | |
6a1e7f77 CL |
364 | |
365 | #ifdef CONFIG_HIGHMEM | |
1da177e4 | 366 | /* |
6a1e7f77 CL |
367 | * Must use a macro here due to header dependency issues. page_zone() is not |
368 | * available at this point. | |
1da177e4 | 369 | */ |
3ca65c19 | 370 | #define PageHighMem(__p) is_highmem_idx(page_zonenum(__p)) |
6a1e7f77 | 371 | #else |
ec7cade8 | 372 | PAGEFLAG_FALSE(HighMem) |
6a1e7f77 CL |
373 | #endif |
374 | ||
375 | #ifdef CONFIG_SWAP | |
6326fec1 NP |
376 | static __always_inline int PageSwapCache(struct page *page) |
377 | { | |
38d8b4e6 HY |
378 | #ifdef CONFIG_THP_SWAP |
379 | page = compound_head(page); | |
380 | #endif | |
6326fec1 NP |
381 | return PageSwapBacked(page) && test_bit(PG_swapcache, &page->flags); |
382 | ||
383 | } | |
38d8b4e6 HY |
384 | SETPAGEFLAG(SwapCache, swapcache, PF_NO_TAIL) |
385 | CLEARPAGEFLAG(SwapCache, swapcache, PF_NO_TAIL) | |
6a1e7f77 | 386 | #else |
ec7cade8 | 387 | PAGEFLAG_FALSE(SwapCache) |
6a1e7f77 CL |
388 | #endif |
389 | ||
8cb38fab KS |
390 | PAGEFLAG(Unevictable, unevictable, PF_HEAD) |
391 | __CLEARPAGEFLAG(Unevictable, unevictable, PF_HEAD) | |
392 | TESTCLEARFLAG(Unevictable, unevictable, PF_HEAD) | |
b291f000 | 393 | |
af8e3354 | 394 | #ifdef CONFIG_MMU |
e4f87d5d KS |
395 | PAGEFLAG(Mlocked, mlocked, PF_NO_TAIL) |
396 | __CLEARPAGEFLAG(Mlocked, mlocked, PF_NO_TAIL) | |
397 | TESTSCFLAG(Mlocked, mlocked, PF_NO_TAIL) | |
894bc310 | 398 | #else |
2f3e442c | 399 | PAGEFLAG_FALSE(Mlocked) __CLEARPAGEFLAG_NOOP(Mlocked) |
685eaade | 400 | TESTSCFLAG_FALSE(Mlocked) |
894bc310 LS |
401 | #endif |
402 | ||
46cf98cd | 403 | #ifdef CONFIG_ARCH_USES_PG_UNCACHED |
b9d41817 | 404 | PAGEFLAG(Uncached, uncached, PF_NO_COMPOUND) |
602c4d11 | 405 | #else |
ec7cade8 | 406 | PAGEFLAG_FALSE(Uncached) |
6a1e7f77 | 407 | #endif |
1da177e4 | 408 | |
d466f2fc | 409 | #ifdef CONFIG_MEMORY_FAILURE |
95ad9755 KS |
410 | PAGEFLAG(HWPoison, hwpoison, PF_ANY) |
411 | TESTSCFLAG(HWPoison, hwpoison, PF_ANY) | |
d466f2fc | 412 | #define __PG_HWPOISON (1UL << PG_hwpoison) |
d4ae9916 | 413 | extern bool set_hwpoison_free_buddy_page(struct page *page); |
d466f2fc AK |
414 | #else |
415 | PAGEFLAG_FALSE(HWPoison) | |
d4ae9916 NH |
416 | static inline bool set_hwpoison_free_buddy_page(struct page *page) |
417 | { | |
418 | return 0; | |
419 | } | |
d466f2fc AK |
420 | #define __PG_HWPOISON 0 |
421 | #endif | |
422 | ||
33c3fc71 | 423 | #if defined(CONFIG_IDLE_PAGE_TRACKING) && defined(CONFIG_64BIT) |
95ad9755 KS |
424 | TESTPAGEFLAG(Young, young, PF_ANY) |
425 | SETPAGEFLAG(Young, young, PF_ANY) | |
426 | TESTCLEARFLAG(Young, young, PF_ANY) | |
427 | PAGEFLAG(Idle, idle, PF_ANY) | |
33c3fc71 VD |
428 | #endif |
429 | ||
e8c6158f KS |
430 | /* |
431 | * On an anonymous page mapped into a user virtual memory area, | |
432 | * page->mapping points to its anon_vma, not to a struct address_space; | |
433 | * with the PAGE_MAPPING_ANON bit set to distinguish it. See rmap.h. | |
434 | * | |
435 | * On an anonymous page in a VM_MERGEABLE area, if CONFIG_KSM is enabled, | |
bda807d4 MK |
436 | * the PAGE_MAPPING_MOVABLE bit may be set along with the PAGE_MAPPING_ANON |
437 | * bit; and then page->mapping points, not to an anon_vma, but to a private | |
e8c6158f KS |
438 | * structure which KSM associates with that merged page. See ksm.h. |
439 | * | |
bda807d4 MK |
440 | * PAGE_MAPPING_KSM without PAGE_MAPPING_ANON is used for non-lru movable |
441 | * page and then page->mapping points a struct address_space. | |
e8c6158f KS |
442 | * |
443 | * Please note that, confusingly, "page_mapping" refers to the inode | |
444 | * address_space which maps the page from disk; whereas "page_mapped" | |
445 | * refers to user virtual address space into which the page is mapped. | |
446 | */ | |
bda807d4 MK |
447 | #define PAGE_MAPPING_ANON 0x1 |
448 | #define PAGE_MAPPING_MOVABLE 0x2 | |
449 | #define PAGE_MAPPING_KSM (PAGE_MAPPING_ANON | PAGE_MAPPING_MOVABLE) | |
450 | #define PAGE_MAPPING_FLAGS (PAGE_MAPPING_ANON | PAGE_MAPPING_MOVABLE) | |
e8c6158f | 451 | |
bda807d4 | 452 | static __always_inline int PageMappingFlags(struct page *page) |
17514574 | 453 | { |
bda807d4 | 454 | return ((unsigned long)page->mapping & PAGE_MAPPING_FLAGS) != 0; |
17514574 MG |
455 | } |
456 | ||
4b0f3261 | 457 | static __always_inline int PageAnon(struct page *page) |
e8c6158f | 458 | { |
822cdd11 | 459 | page = compound_head(page); |
bda807d4 MK |
460 | return ((unsigned long)page->mapping & PAGE_MAPPING_ANON) != 0; |
461 | } | |
462 | ||
463 | static __always_inline int __PageMovable(struct page *page) | |
464 | { | |
465 | return ((unsigned long)page->mapping & PAGE_MAPPING_FLAGS) == | |
466 | PAGE_MAPPING_MOVABLE; | |
e8c6158f KS |
467 | } |
468 | ||
469 | #ifdef CONFIG_KSM | |
470 | /* | |
471 | * A KSM page is one of those write-protected "shared pages" or "merged pages" | |
472 | * which KSM maps into multiple mms, wherever identical anonymous page content | |
473 | * is found in VM_MERGEABLE vmas. It's a PageAnon page, pointing not to any | |
474 | * anon_vma, but to that page's node of the stable tree. | |
475 | */ | |
4b0f3261 | 476 | static __always_inline int PageKsm(struct page *page) |
e8c6158f | 477 | { |
822cdd11 | 478 | page = compound_head(page); |
e8c6158f | 479 | return ((unsigned long)page->mapping & PAGE_MAPPING_FLAGS) == |
bda807d4 | 480 | PAGE_MAPPING_KSM; |
e8c6158f KS |
481 | } |
482 | #else | |
483 | TESTPAGEFLAG_FALSE(Ksm) | |
484 | #endif | |
485 | ||
1a9b5b7f WF |
486 | u64 stable_page_flags(struct page *page); |
487 | ||
0ed361de NP |
488 | static inline int PageUptodate(struct page *page) |
489 | { | |
d2998c4d KS |
490 | int ret; |
491 | page = compound_head(page); | |
492 | ret = test_bit(PG_uptodate, &(page)->flags); | |
0ed361de NP |
493 | /* |
494 | * Must ensure that the data we read out of the page is loaded | |
495 | * _after_ we've loaded page->flags to check for PageUptodate. | |
496 | * We can skip the barrier if the page is not uptodate, because | |
497 | * we wouldn't be reading anything from it. | |
498 | * | |
499 | * See SetPageUptodate() for the other side of the story. | |
500 | */ | |
501 | if (ret) | |
502 | smp_rmb(); | |
503 | ||
504 | return ret; | |
505 | } | |
506 | ||
4b0f3261 | 507 | static __always_inline void __SetPageUptodate(struct page *page) |
0ed361de | 508 | { |
d2998c4d | 509 | VM_BUG_ON_PAGE(PageTail(page), page); |
0ed361de | 510 | smp_wmb(); |
df8c94d1 | 511 | __set_bit(PG_uptodate, &page->flags); |
0ed361de NP |
512 | } |
513 | ||
4b0f3261 | 514 | static __always_inline void SetPageUptodate(struct page *page) |
2dcea57a | 515 | { |
d2998c4d | 516 | VM_BUG_ON_PAGE(PageTail(page), page); |
0ed361de NP |
517 | /* |
518 | * Memory barrier must be issued before setting the PG_uptodate bit, | |
519 | * so that all previous stores issued in order to bring the page | |
520 | * uptodate are actually visible before PageUptodate becomes true. | |
0ed361de NP |
521 | */ |
522 | smp_wmb(); | |
df8c94d1 | 523 | set_bit(PG_uptodate, &page->flags); |
0ed361de NP |
524 | } |
525 | ||
d2998c4d | 526 | CLEARPAGEFLAG(Uptodate, uptodate, PF_NO_TAIL) |
1da177e4 | 527 | |
6a1e7f77 | 528 | int test_clear_page_writeback(struct page *page); |
1c8349a1 NJ |
529 | int __test_set_page_writeback(struct page *page, bool keep_write); |
530 | ||
531 | #define test_set_page_writeback(page) \ | |
532 | __test_set_page_writeback(page, false) | |
533 | #define test_set_page_writeback_keepwrite(page) \ | |
534 | __test_set_page_writeback(page, true) | |
1da177e4 | 535 | |
6a1e7f77 CL |
536 | static inline void set_page_writeback(struct page *page) |
537 | { | |
538 | test_set_page_writeback(page); | |
539 | } | |
1da177e4 | 540 | |
1c8349a1 NJ |
541 | static inline void set_page_writeback_keepwrite(struct page *page) |
542 | { | |
543 | test_set_page_writeback_keepwrite(page); | |
544 | } | |
545 | ||
95ad9755 | 546 | __PAGEFLAG(Head, head, PF_ANY) CLEARPAGEFLAG(Head, head, PF_ANY) |
e20b8cca | 547 | |
4b0f3261 | 548 | static __always_inline void set_compound_head(struct page *page, struct page *head) |
ad4b3fb7 | 549 | { |
1d798ca3 | 550 | WRITE_ONCE(page->compound_head, (unsigned long)head + 1); |
ad4b3fb7 CD |
551 | } |
552 | ||
4b0f3261 | 553 | static __always_inline void clear_compound_head(struct page *page) |
6a1e7f77 | 554 | { |
1d798ca3 | 555 | WRITE_ONCE(page->compound_head, 0); |
6a1e7f77 | 556 | } |
6d777953 | 557 | |
4e6af67e AA |
558 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
559 | static inline void ClearPageCompound(struct page *page) | |
560 | { | |
1d798ca3 KS |
561 | BUG_ON(!PageHead(page)); |
562 | ClearPageHead(page); | |
4e6af67e AA |
563 | } |
564 | #endif | |
565 | ||
d2a1a1f0 | 566 | #define PG_head_mask ((1UL << PG_head)) |
dfa7e20c | 567 | |
e8c6158f KS |
568 | #ifdef CONFIG_HUGETLB_PAGE |
569 | int PageHuge(struct page *page); | |
570 | int PageHeadHuge(struct page *page); | |
7e1f049e | 571 | bool page_huge_active(struct page *page); |
e8c6158f KS |
572 | #else |
573 | TESTPAGEFLAG_FALSE(Huge) | |
574 | TESTPAGEFLAG_FALSE(HeadHuge) | |
7e1f049e NH |
575 | |
576 | static inline bool page_huge_active(struct page *page) | |
577 | { | |
578 | return 0; | |
579 | } | |
e8c6158f KS |
580 | #endif |
581 | ||
7e1f049e | 582 | |
936a5fe6 | 583 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
71e3aac0 AA |
584 | /* |
585 | * PageHuge() only returns true for hugetlbfs pages, but not for | |
586 | * normal or transparent huge pages. | |
587 | * | |
588 | * PageTransHuge() returns true for both transparent huge and | |
589 | * hugetlbfs pages, but not normal pages. PageTransHuge() can only be | |
590 | * called only in the core VM paths where hugetlbfs pages can't exist. | |
591 | */ | |
592 | static inline int PageTransHuge(struct page *page) | |
593 | { | |
309381fe | 594 | VM_BUG_ON_PAGE(PageTail(page), page); |
71e3aac0 AA |
595 | return PageHead(page); |
596 | } | |
597 | ||
385de357 DN |
598 | /* |
599 | * PageTransCompound returns true for both transparent huge pages | |
600 | * and hugetlbfs pages, so it should only be called when it's known | |
601 | * that hugetlbfs pages aren't involved. | |
602 | */ | |
936a5fe6 AA |
603 | static inline int PageTransCompound(struct page *page) |
604 | { | |
605 | return PageCompound(page); | |
606 | } | |
71e3aac0 | 607 | |
127393fb AA |
608 | /* |
609 | * PageTransCompoundMap is the same as PageTransCompound, but it also | |
610 | * guarantees the primary MMU has the entire compound page mapped | |
611 | * through pmd_trans_huge, which in turn guarantees the secondary MMUs | |
612 | * can also map the entire compound page. This allows the secondary | |
613 | * MMUs to call get_user_pages() only once for each compound page and | |
614 | * to immediately map the entire compound page with a single secondary | |
615 | * MMU fault. If there will be a pmd split later, the secondary MMUs | |
616 | * will get an update through the MMU notifier invalidation through | |
617 | * split_huge_pmd(). | |
618 | * | |
619 | * Unlike PageTransCompound, this is safe to be called only while | |
620 | * split_huge_pmd() cannot run from under us, like if protected by the | |
621 | * MMU notifier, otherwise it may result in page->_mapcount < 0 false | |
622 | * positives. | |
623 | */ | |
624 | static inline int PageTransCompoundMap(struct page *page) | |
625 | { | |
626 | return PageTransCompound(page) && atomic_read(&page->_mapcount) < 0; | |
627 | } | |
628 | ||
385de357 DN |
629 | /* |
630 | * PageTransTail returns true for both transparent huge pages | |
631 | * and hugetlbfs pages, so it should only be called when it's known | |
632 | * that hugetlbfs pages aren't involved. | |
633 | */ | |
634 | static inline int PageTransTail(struct page *page) | |
635 | { | |
636 | return PageTail(page); | |
637 | } | |
638 | ||
53f9263b KS |
639 | /* |
640 | * PageDoubleMap indicates that the compound page is mapped with PTEs as well | |
641 | * as PMDs. | |
642 | * | |
643 | * This is required for optimization of rmap operations for THP: we can postpone | |
644 | * per small page mapcount accounting (and its overhead from atomic operations) | |
645 | * until the first PMD split. | |
646 | * | |
647 | * For the page PageDoubleMap means ->_mapcount in all sub-pages is offset up | |
648 | * by one. This reference will go away with last compound_mapcount. | |
649 | * | |
650 | * See also __split_huge_pmd_locked() and page_remove_anon_compound_rmap(). | |
651 | */ | |
652 | static inline int PageDoubleMap(struct page *page) | |
653 | { | |
654 | return PageHead(page) && test_bit(PG_double_map, &page[1].flags); | |
655 | } | |
656 | ||
9a73f61b KS |
657 | static inline void SetPageDoubleMap(struct page *page) |
658 | { | |
659 | VM_BUG_ON_PAGE(!PageHead(page), page); | |
660 | set_bit(PG_double_map, &page[1].flags); | |
661 | } | |
662 | ||
663 | static inline void ClearPageDoubleMap(struct page *page) | |
664 | { | |
665 | VM_BUG_ON_PAGE(!PageHead(page), page); | |
666 | clear_bit(PG_double_map, &page[1].flags); | |
667 | } | |
53f9263b KS |
668 | static inline int TestSetPageDoubleMap(struct page *page) |
669 | { | |
670 | VM_BUG_ON_PAGE(!PageHead(page), page); | |
671 | return test_and_set_bit(PG_double_map, &page[1].flags); | |
672 | } | |
673 | ||
674 | static inline int TestClearPageDoubleMap(struct page *page) | |
675 | { | |
676 | VM_BUG_ON_PAGE(!PageHead(page), page); | |
677 | return test_and_clear_bit(PG_double_map, &page[1].flags); | |
678 | } | |
679 | ||
936a5fe6 | 680 | #else |
d8c1bdeb KS |
681 | TESTPAGEFLAG_FALSE(TransHuge) |
682 | TESTPAGEFLAG_FALSE(TransCompound) | |
127393fb | 683 | TESTPAGEFLAG_FALSE(TransCompoundMap) |
d8c1bdeb | 684 | TESTPAGEFLAG_FALSE(TransTail) |
9a73f61b | 685 | PAGEFLAG_FALSE(DoubleMap) |
53f9263b KS |
686 | TESTSETFLAG_FALSE(DoubleMap) |
687 | TESTCLEARFLAG_FALSE(DoubleMap) | |
936a5fe6 AA |
688 | #endif |
689 | ||
e8c6158f | 690 | /* |
6e292b9b MW |
691 | * For pages that are never mapped to userspace (and aren't PageSlab), |
692 | * page_type may be used. Because it is initialised to -1, we invert the | |
693 | * sense of the bit, so __SetPageFoo *clears* the bit used for PageFoo, and | |
694 | * __ClearPageFoo *sets* the bit used for PageFoo. We reserve a few high and | |
695 | * low bits so that an underflow or overflow of page_mapcount() won't be | |
696 | * mistaken for a page type value. | |
e8c6158f | 697 | */ |
6e292b9b MW |
698 | |
699 | #define PAGE_TYPE_BASE 0xf0000000 | |
700 | /* Reserve 0x0000007f to catch underflows of page_mapcount */ | |
144552ff | 701 | #define PAGE_MAPCOUNT_RESERVE -128 |
6e292b9b | 702 | #define PG_buddy 0x00000080 |
ca215086 | 703 | #define PG_offline 0x00000100 |
6e292b9b | 704 | #define PG_kmemcg 0x00000200 |
1d40a5ea | 705 | #define PG_table 0x00000400 |
3972f6bb | 706 | #define PG_guard 0x00000800 |
6e292b9b MW |
707 | |
708 | #define PageType(page, flag) \ | |
709 | ((page->page_type & (PAGE_TYPE_BASE | flag)) == PAGE_TYPE_BASE) | |
710 | ||
144552ff AY |
711 | static inline int page_has_type(struct page *page) |
712 | { | |
713 | return (int)page->page_type < PAGE_MAPCOUNT_RESERVE; | |
714 | } | |
715 | ||
6e292b9b | 716 | #define PAGE_TYPE_OPS(uname, lname) \ |
632c0a1a VD |
717 | static __always_inline int Page##uname(struct page *page) \ |
718 | { \ | |
6e292b9b | 719 | return PageType(page, PG_##lname); \ |
632c0a1a VD |
720 | } \ |
721 | static __always_inline void __SetPage##uname(struct page *page) \ | |
722 | { \ | |
6e292b9b MW |
723 | VM_BUG_ON_PAGE(!PageType(page, 0), page); \ |
724 | page->page_type &= ~PG_##lname; \ | |
632c0a1a VD |
725 | } \ |
726 | static __always_inline void __ClearPage##uname(struct page *page) \ | |
727 | { \ | |
728 | VM_BUG_ON_PAGE(!Page##uname(page), page); \ | |
6e292b9b | 729 | page->page_type |= PG_##lname; \ |
e8c6158f KS |
730 | } |
731 | ||
632c0a1a | 732 | /* |
6e292b9b | 733 | * PageBuddy() indicates that the page is free and in the buddy system |
632c0a1a VD |
734 | * (see mm/page_alloc.c). |
735 | */ | |
6e292b9b | 736 | PAGE_TYPE_OPS(Buddy, buddy) |
e8c6158f | 737 | |
632c0a1a | 738 | /* |
ca215086 DH |
739 | * PageOffline() indicates that the page is logically offline although the |
740 | * containing section is online. (e.g. inflated in a balloon driver or | |
741 | * not onlined when onlining the section). | |
742 | * The content of these pages is effectively stale. Such pages should not | |
743 | * be touched (read/write/dump/save) except by their owner. | |
632c0a1a | 744 | */ |
ca215086 | 745 | PAGE_TYPE_OPS(Offline, offline) |
e8c6158f | 746 | |
4949148a VD |
747 | /* |
748 | * If kmemcg is enabled, the buddy allocator will set PageKmemcg() on | |
749 | * pages allocated with __GFP_ACCOUNT. It gets cleared on page free. | |
750 | */ | |
6e292b9b | 751 | PAGE_TYPE_OPS(Kmemcg, kmemcg) |
4949148a | 752 | |
1d40a5ea MW |
753 | /* |
754 | * Marks pages in use as page tables. | |
755 | */ | |
756 | PAGE_TYPE_OPS(Table, table) | |
757 | ||
3972f6bb VB |
758 | /* |
759 | * Marks guardpages used with debug_pagealloc. | |
760 | */ | |
761 | PAGE_TYPE_OPS(Guard, guard) | |
762 | ||
832fc1de NH |
763 | extern bool is_free_buddy_page(struct page *page); |
764 | ||
bda807d4 MK |
765 | __PAGEFLAG(Isolated, isolated, PF_ANY); |
766 | ||
072bb0aa MG |
767 | /* |
768 | * If network-based swap is enabled, sl*b must keep track of whether pages | |
769 | * were allocated from pfmemalloc reserves. | |
770 | */ | |
771 | static inline int PageSlabPfmemalloc(struct page *page) | |
772 | { | |
309381fe | 773 | VM_BUG_ON_PAGE(!PageSlab(page), page); |
072bb0aa MG |
774 | return PageActive(page); |
775 | } | |
776 | ||
777 | static inline void SetPageSlabPfmemalloc(struct page *page) | |
778 | { | |
309381fe | 779 | VM_BUG_ON_PAGE(!PageSlab(page), page); |
072bb0aa MG |
780 | SetPageActive(page); |
781 | } | |
782 | ||
783 | static inline void __ClearPageSlabPfmemalloc(struct page *page) | |
784 | { | |
309381fe | 785 | VM_BUG_ON_PAGE(!PageSlab(page), page); |
072bb0aa MG |
786 | __ClearPageActive(page); |
787 | } | |
788 | ||
789 | static inline void ClearPageSlabPfmemalloc(struct page *page) | |
790 | { | |
309381fe | 791 | VM_BUG_ON_PAGE(!PageSlab(page), page); |
072bb0aa MG |
792 | ClearPageActive(page); |
793 | } | |
794 | ||
af8e3354 | 795 | #ifdef CONFIG_MMU |
d2a1a1f0 | 796 | #define __PG_MLOCKED (1UL << PG_mlocked) |
33925b25 | 797 | #else |
b291f000 | 798 | #define __PG_MLOCKED 0 |
894bc310 LS |
799 | #endif |
800 | ||
dfa7e20c RA |
801 | /* |
802 | * Flags checked when a page is freed. Pages being freed should not have | |
803 | * these flags set. It they are, there is a problem. | |
804 | */ | |
6326fec1 NP |
805 | #define PAGE_FLAGS_CHECK_AT_FREE \ |
806 | (1UL << PG_lru | 1UL << PG_locked | \ | |
807 | 1UL << PG_private | 1UL << PG_private_2 | \ | |
808 | 1UL << PG_writeback | 1UL << PG_reserved | \ | |
809 | 1UL << PG_slab | 1UL << PG_active | \ | |
810 | 1UL << PG_unevictable | __PG_MLOCKED) | |
dfa7e20c RA |
811 | |
812 | /* | |
813 | * Flags checked when a page is prepped for return by the page allocator. | |
f4c18e6f | 814 | * Pages being prepped should not have these flags set. It they are set, |
79f4b7bf | 815 | * there has been a kernel bug or struct page corruption. |
f4c18e6f NH |
816 | * |
817 | * __PG_HWPOISON is exceptional because it needs to be kept beyond page's | |
818 | * alloc-free cycle to prevent from reusing the page. | |
dfa7e20c | 819 | */ |
f4c18e6f | 820 | #define PAGE_FLAGS_CHECK_AT_PREP \ |
d2a1a1f0 | 821 | (((1UL << NR_PAGEFLAGS) - 1) & ~__PG_HWPOISON) |
dfa7e20c | 822 | |
edcf4748 | 823 | #define PAGE_FLAGS_PRIVATE \ |
d2a1a1f0 | 824 | (1UL << PG_private | 1UL << PG_private_2) |
266cf658 DH |
825 | /** |
826 | * page_has_private - Determine if page has private stuff | |
827 | * @page: The page to be checked | |
828 | * | |
829 | * Determine if a page has private stuff, indicating that release routines | |
830 | * should be invoked upon it. | |
831 | */ | |
edcf4748 JW |
832 | static inline int page_has_private(struct page *page) |
833 | { | |
834 | return !!(page->flags & PAGE_FLAGS_PRIVATE); | |
835 | } | |
836 | ||
95ad9755 KS |
837 | #undef PF_ANY |
838 | #undef PF_HEAD | |
62906027 | 839 | #undef PF_ONLY_HEAD |
95ad9755 KS |
840 | #undef PF_NO_TAIL |
841 | #undef PF_NO_COMPOUND | |
edcf4748 | 842 | #endif /* !__GENERATING_BOUNDS_H */ |
266cf658 | 843 | |
1da177e4 | 844 | #endif /* PAGE_FLAGS_H */ |