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 | 65 | * |
9de4f22a HY |
66 | * PG_swapbacked is set when a page uses swap as a backing storage. This are |
67 | * usually PageAnon or shmem pages but please note that even anonymous pages | |
68 | * might lose their PG_swapbacked flag when they simply can be dropped (e.g. as | |
69 | * a result of MADV_FREE). | |
70 | * | |
da6052f7 NP |
71 | * PG_referenced, PG_reclaim are used for page reclaim for anonymous and |
72 | * file-backed pagecache (see mm/vmscan.c). | |
1da177e4 LT |
73 | * |
74 | * PG_error is set to indicate that an I/O error occurred on this page. | |
75 | * | |
76 | * PG_arch_1 is an architecture specific page state bit. The generic code | |
77 | * guarantees that this bit is cleared for a page when it first is entered into | |
78 | * the page cache. | |
79 | * | |
d466f2fc AK |
80 | * PG_hwpoison indicates that a page got corrupted in hardware and contains |
81 | * data with incorrect ECC bits that triggered a machine check. Accessing is | |
82 | * not safe since it may cause another machine check. Don't touch! | |
1da177e4 LT |
83 | */ |
84 | ||
85 | /* | |
3b12da6d | 86 | * Don't use the pageflags directly. Use the PageFoo macros. |
91fc8ab3 AW |
87 | * |
88 | * The page flags field is split into two parts, the main flags area | |
89 | * which extends from the low bits upwards, and the fields area which | |
90 | * extends from the high bits downwards. | |
91 | * | |
92 | * | FIELD | ... | FLAGS | | |
9223b419 CL |
93 | * N-1 ^ 0 |
94 | * (NR_PAGEFLAGS) | |
91fc8ab3 | 95 | * |
9223b419 CL |
96 | * The fields area is reserved for fields mapping zone, node (for NUMA) and |
97 | * SPARSEMEM section (for variants of SPARSEMEM that require section ids like | |
98 | * SPARSEMEM_EXTREME with !SPARSEMEM_VMEMMAP). | |
1da177e4 | 99 | */ |
e2683181 CL |
100 | enum pageflags { |
101 | PG_locked, /* Page is locked. Don't touch. */ | |
e2683181 CL |
102 | PG_referenced, |
103 | PG_uptodate, | |
104 | PG_dirty, | |
105 | PG_lru, | |
106 | PG_active, | |
1899ad18 | 107 | PG_workingset, |
b91e1302 | 108 | PG_waiters, /* Page has waiters, check its waitqueue. Must be bit #7 and in the same byte as "PG_locked" */ |
1899ad18 | 109 | PG_error, |
e2683181 CL |
110 | PG_slab, |
111 | PG_owner_priv_1, /* Owner use. If pagecache, fs may use*/ | |
e2683181 CL |
112 | PG_arch_1, |
113 | PG_reserved, | |
114 | PG_private, /* If pagecache, has fs-private data */ | |
266cf658 | 115 | PG_private_2, /* If pagecache, has fs aux data */ |
e2683181 | 116 | PG_writeback, /* Page is under writeback */ |
e20b8cca | 117 | PG_head, /* A head page */ |
e2683181 CL |
118 | PG_mappedtodisk, /* Has blocks allocated on-disk */ |
119 | PG_reclaim, /* To be reclaimed asap */ | |
b2e18538 | 120 | PG_swapbacked, /* Page is backed by RAM/swap */ |
894bc310 | 121 | PG_unevictable, /* Page is "unevictable" */ |
af8e3354 | 122 | #ifdef CONFIG_MMU |
b291f000 | 123 | PG_mlocked, /* Page is vma mlocked */ |
894bc310 | 124 | #endif |
46cf98cd | 125 | #ifdef CONFIG_ARCH_USES_PG_UNCACHED |
602c4d11 | 126 | PG_uncached, /* Page has been mapped as uncached */ |
d466f2fc AK |
127 | #endif |
128 | #ifdef CONFIG_MEMORY_FAILURE | |
129 | PG_hwpoison, /* hardware poisoned page. Don't touch */ | |
e9da73d6 | 130 | #endif |
1c676e0d | 131 | #if defined(CONFIG_PAGE_IDLE_FLAG) && defined(CONFIG_64BIT) |
33c3fc71 VD |
132 | PG_young, |
133 | PG_idle, | |
4beba948 SP |
134 | #endif |
135 | #ifdef CONFIG_64BIT | |
136 | PG_arch_2, | |
c275c5c6 PC |
137 | #endif |
138 | #ifdef CONFIG_KASAN_HW_TAGS | |
139 | PG_skip_kasan_poison, | |
f886ed44 | 140 | #endif |
0cad47cf AW |
141 | __NR_PAGEFLAGS, |
142 | ||
d389a4a8 MWO |
143 | PG_readahead = PG_reclaim, |
144 | ||
0cad47cf AW |
145 | /* Filesystems */ |
146 | PG_checked = PG_owner_priv_1, | |
147 | ||
6326fec1 NP |
148 | /* SwapBacked */ |
149 | PG_swapcache = PG_owner_priv_1, /* Swap page: swp_entry_t in private */ | |
150 | ||
266cf658 DH |
151 | /* Two page bits are conscripted by FS-Cache to maintain local caching |
152 | * state. These bits are set on pages belonging to the netfs's inodes | |
153 | * when those inodes are being locally cached. | |
154 | */ | |
155 | PG_fscache = PG_private_2, /* page backed by cache */ | |
156 | ||
0cad47cf | 157 | /* XEN */ |
d8ac3dd4 | 158 | /* Pinned in Xen as a read-only pagetable page. */ |
0cad47cf | 159 | PG_pinned = PG_owner_priv_1, |
d8ac3dd4 | 160 | /* Pinned as part of domain save (see xen_mm_pin_all()). */ |
0cad47cf | 161 | PG_savepinned = PG_dirty, |
d8ac3dd4 JH |
162 | /* Has a grant mapping of another (foreign) domain's page. */ |
163 | PG_foreign = PG_owner_priv_1, | |
b877ac98 JG |
164 | /* Remapped by swiotlb-xen. */ |
165 | PG_xen_remapped = PG_owner_priv_1, | |
8a38082d | 166 | |
9023cb7e | 167 | /* SLOB */ |
9023cb7e | 168 | PG_slob_free = PG_private, |
53f9263b KS |
169 | |
170 | /* Compound pages. Stored in first tail page's flags */ | |
e18c45ff | 171 | PG_double_map = PG_workingset, |
bda807d4 | 172 | |
eac96c3e YS |
173 | #ifdef CONFIG_MEMORY_FAILURE |
174 | /* | |
175 | * Compound pages. Stored in first tail page's flags. | |
176 | * Indicates that at least one subpage is hwpoisoned in the | |
177 | * THP. | |
178 | */ | |
179 | PG_has_hwpoisoned = PG_mappedtodisk, | |
180 | #endif | |
181 | ||
bda807d4 MK |
182 | /* non-lru isolated movable page */ |
183 | PG_isolated = PG_reclaim, | |
36e66c55 AD |
184 | |
185 | /* Only valid for buddy pages. Used to track pages that are reported */ | |
186 | PG_reported = PG_uptodate, | |
e2683181 | 187 | }; |
1da177e4 | 188 | |
41c961b9 MS |
189 | #define PAGEFLAGS_MASK ((1UL << NR_PAGEFLAGS) - 1) |
190 | ||
9223b419 CL |
191 | #ifndef __GENERATING_BOUNDS_H |
192 | ||
0f2317e3 | 193 | static inline unsigned long _compound_head(const struct page *page) |
0e6d31a7 KS |
194 | { |
195 | unsigned long head = READ_ONCE(page->compound_head); | |
196 | ||
197 | if (unlikely(head & 1)) | |
0f2317e3 MWO |
198 | return head - 1; |
199 | return (unsigned long)page; | |
0e6d31a7 KS |
200 | } |
201 | ||
0f2317e3 MWO |
202 | #define compound_head(page) ((typeof(page))_compound_head(page)) |
203 | ||
7b230db3 MWO |
204 | /** |
205 | * page_folio - Converts from page to folio. | |
206 | * @p: The page. | |
207 | * | |
208 | * Every page is part of a folio. This function cannot be called on a | |
209 | * NULL pointer. | |
210 | * | |
211 | * Context: No reference, nor lock is required on @page. If the caller | |
212 | * does not hold a reference, this call may race with a folio split, so | |
213 | * it should re-check the folio still contains this page after gaining | |
214 | * a reference on the folio. | |
215 | * Return: The folio which contains this page. | |
216 | */ | |
217 | #define page_folio(p) (_Generic((p), \ | |
218 | const struct page *: (const struct folio *)_compound_head(p), \ | |
219 | struct page *: (struct folio *)_compound_head(p))) | |
220 | ||
221 | /** | |
222 | * folio_page - Return a page from a folio. | |
223 | * @folio: The folio. | |
224 | * @n: The page number to return. | |
225 | * | |
226 | * @n is relative to the start of the folio. This function does not | |
227 | * check that the page number lies within @folio; the caller is presumed | |
228 | * to have a reference to the page. | |
229 | */ | |
230 | #define folio_page(folio, n) nth_page(&(folio)->page, n) | |
231 | ||
4b0f3261 | 232 | static __always_inline int PageTail(struct page *page) |
0e6d31a7 KS |
233 | { |
234 | return READ_ONCE(page->compound_head) & 1; | |
235 | } | |
236 | ||
4b0f3261 | 237 | static __always_inline int PageCompound(struct page *page) |
0e6d31a7 KS |
238 | { |
239 | return test_bit(PG_head, &page->flags) || PageTail(page); | |
240 | } | |
241 | ||
f165b378 PT |
242 | #define PAGE_POISON_PATTERN -1l |
243 | static inline int PagePoisoned(const struct page *page) | |
244 | { | |
477d01fc | 245 | return READ_ONCE(page->flags) == PAGE_POISON_PATTERN; |
f165b378 PT |
246 | } |
247 | ||
f682a97a AD |
248 | #ifdef CONFIG_DEBUG_VM |
249 | void page_init_poison(struct page *page, size_t size); | |
250 | #else | |
251 | static inline void page_init_poison(struct page *page, size_t size) | |
252 | { | |
253 | } | |
254 | #endif | |
255 | ||
d389a4a8 MWO |
256 | static unsigned long *folio_flags(struct folio *folio, unsigned n) |
257 | { | |
258 | struct page *page = &folio->page; | |
259 | ||
260 | VM_BUG_ON_PGFLAGS(PageTail(page), page); | |
261 | VM_BUG_ON_PGFLAGS(n > 0 && !test_bit(PG_head, &page->flags), page); | |
262 | return &page[n].flags; | |
263 | } | |
264 | ||
95ad9755 KS |
265 | /* |
266 | * Page flags policies wrt compound pages | |
267 | * | |
f165b378 PT |
268 | * PF_POISONED_CHECK |
269 | * check if this struct page poisoned/uninitialized | |
270 | * | |
95ad9755 KS |
271 | * PF_ANY: |
272 | * the page flag is relevant for small, head and tail pages. | |
273 | * | |
274 | * PF_HEAD: | |
275 | * for compound page all operations related to the page flag applied to | |
276 | * head page. | |
277 | * | |
62906027 NP |
278 | * PF_ONLY_HEAD: |
279 | * for compound page, callers only ever operate on the head page. | |
280 | * | |
95ad9755 KS |
281 | * PF_NO_TAIL: |
282 | * modifications of the page flag must be done on small or head pages, | |
283 | * checks can be done on tail pages too. | |
284 | * | |
285 | * PF_NO_COMPOUND: | |
286 | * the page flag is not relevant for compound pages. | |
a08d93e5 MWO |
287 | * |
288 | * PF_SECOND: | |
289 | * the page flag is stored in the first tail page. | |
95ad9755 | 290 | */ |
f165b378 PT |
291 | #define PF_POISONED_CHECK(page) ({ \ |
292 | VM_BUG_ON_PGFLAGS(PagePoisoned(page), page); \ | |
293 | page; }) | |
294 | #define PF_ANY(page, enforce) PF_POISONED_CHECK(page) | |
295 | #define PF_HEAD(page, enforce) PF_POISONED_CHECK(compound_head(page)) | |
62906027 NP |
296 | #define PF_ONLY_HEAD(page, enforce) ({ \ |
297 | VM_BUG_ON_PGFLAGS(PageTail(page), page); \ | |
f165b378 | 298 | PF_POISONED_CHECK(page); }) |
95ad9755 KS |
299 | #define PF_NO_TAIL(page, enforce) ({ \ |
300 | VM_BUG_ON_PGFLAGS(enforce && PageTail(page), page); \ | |
f165b378 | 301 | PF_POISONED_CHECK(compound_head(page)); }) |
822cdd11 | 302 | #define PF_NO_COMPOUND(page, enforce) ({ \ |
95ad9755 | 303 | VM_BUG_ON_PGFLAGS(enforce && PageCompound(page), page); \ |
f165b378 | 304 | PF_POISONED_CHECK(page); }) |
a08d93e5 MWO |
305 | #define PF_SECOND(page, enforce) ({ \ |
306 | VM_BUG_ON_PGFLAGS(!PageHead(page), page); \ | |
307 | PF_POISONED_CHECK(&page[1]); }) | |
95ad9755 | 308 | |
d389a4a8 MWO |
309 | /* Which page is the flag stored in */ |
310 | #define FOLIO_PF_ANY 0 | |
311 | #define FOLIO_PF_HEAD 0 | |
312 | #define FOLIO_PF_ONLY_HEAD 0 | |
313 | #define FOLIO_PF_NO_TAIL 0 | |
314 | #define FOLIO_PF_NO_COMPOUND 0 | |
315 | #define FOLIO_PF_SECOND 1 | |
316 | ||
f94a62e9 CL |
317 | /* |
318 | * Macros to create function definitions for page flags | |
319 | */ | |
95ad9755 | 320 | #define TESTPAGEFLAG(uname, lname, policy) \ |
d389a4a8 MWO |
321 | static __always_inline bool folio_test_##lname(struct folio *folio) \ |
322 | { return test_bit(PG_##lname, folio_flags(folio, FOLIO_##policy)); } \ | |
4b0f3261 | 323 | static __always_inline int Page##uname(struct page *page) \ |
d389a4a8 | 324 | { return test_bit(PG_##lname, &policy(page, 0)->flags); } |
f94a62e9 | 325 | |
95ad9755 | 326 | #define SETPAGEFLAG(uname, lname, policy) \ |
d389a4a8 MWO |
327 | static __always_inline \ |
328 | void folio_set_##lname(struct folio *folio) \ | |
329 | { set_bit(PG_##lname, folio_flags(folio, FOLIO_##policy)); } \ | |
4b0f3261 | 330 | static __always_inline void SetPage##uname(struct page *page) \ |
d389a4a8 | 331 | { set_bit(PG_##lname, &policy(page, 1)->flags); } |
f94a62e9 | 332 | |
95ad9755 | 333 | #define CLEARPAGEFLAG(uname, lname, policy) \ |
d389a4a8 MWO |
334 | static __always_inline \ |
335 | void folio_clear_##lname(struct folio *folio) \ | |
336 | { clear_bit(PG_##lname, folio_flags(folio, FOLIO_##policy)); } \ | |
4b0f3261 | 337 | static __always_inline void ClearPage##uname(struct page *page) \ |
d389a4a8 | 338 | { clear_bit(PG_##lname, &policy(page, 1)->flags); } |
f94a62e9 | 339 | |
95ad9755 | 340 | #define __SETPAGEFLAG(uname, lname, policy) \ |
d389a4a8 MWO |
341 | static __always_inline \ |
342 | void __folio_set_##lname(struct folio *folio) \ | |
343 | { __set_bit(PG_##lname, folio_flags(folio, FOLIO_##policy)); } \ | |
4b0f3261 | 344 | static __always_inline void __SetPage##uname(struct page *page) \ |
d389a4a8 | 345 | { __set_bit(PG_##lname, &policy(page, 1)->flags); } |
f94a62e9 | 346 | |
95ad9755 | 347 | #define __CLEARPAGEFLAG(uname, lname, policy) \ |
d389a4a8 MWO |
348 | static __always_inline \ |
349 | void __folio_clear_##lname(struct folio *folio) \ | |
350 | { __clear_bit(PG_##lname, folio_flags(folio, FOLIO_##policy)); } \ | |
4b0f3261 | 351 | static __always_inline void __ClearPage##uname(struct page *page) \ |
d389a4a8 | 352 | { __clear_bit(PG_##lname, &policy(page, 1)->flags); } |
f94a62e9 | 353 | |
95ad9755 | 354 | #define TESTSETFLAG(uname, lname, policy) \ |
d389a4a8 MWO |
355 | static __always_inline \ |
356 | bool folio_test_set_##lname(struct folio *folio) \ | |
357 | { return test_and_set_bit(PG_##lname, folio_flags(folio, FOLIO_##policy)); } \ | |
4b0f3261 | 358 | static __always_inline int TestSetPage##uname(struct page *page) \ |
d389a4a8 | 359 | { return test_and_set_bit(PG_##lname, &policy(page, 1)->flags); } |
f94a62e9 | 360 | |
95ad9755 | 361 | #define TESTCLEARFLAG(uname, lname, policy) \ |
d389a4a8 MWO |
362 | static __always_inline \ |
363 | bool folio_test_clear_##lname(struct folio *folio) \ | |
364 | { return test_and_clear_bit(PG_##lname, folio_flags(folio, FOLIO_##policy)); } \ | |
4b0f3261 | 365 | static __always_inline int TestClearPage##uname(struct page *page) \ |
d389a4a8 | 366 | { return test_and_clear_bit(PG_##lname, &policy(page, 1)->flags); } |
f94a62e9 | 367 | |
95ad9755 KS |
368 | #define PAGEFLAG(uname, lname, policy) \ |
369 | TESTPAGEFLAG(uname, lname, policy) \ | |
370 | SETPAGEFLAG(uname, lname, policy) \ | |
371 | CLEARPAGEFLAG(uname, lname, policy) | |
f94a62e9 | 372 | |
95ad9755 KS |
373 | #define __PAGEFLAG(uname, lname, policy) \ |
374 | TESTPAGEFLAG(uname, lname, policy) \ | |
375 | __SETPAGEFLAG(uname, lname, policy) \ | |
376 | __CLEARPAGEFLAG(uname, lname, policy) | |
f94a62e9 | 377 | |
95ad9755 KS |
378 | #define TESTSCFLAG(uname, lname, policy) \ |
379 | TESTSETFLAG(uname, lname, policy) \ | |
380 | TESTCLEARFLAG(uname, lname, policy) | |
f94a62e9 | 381 | |
d389a4a8 | 382 | #define TESTPAGEFLAG_FALSE(uname, lname) \ |
1611f74a | 383 | static inline bool folio_test_##lname(const struct folio *folio) { return false; } \ |
2f3e442c JW |
384 | static inline int Page##uname(const struct page *page) { return 0; } |
385 | ||
d389a4a8 MWO |
386 | #define SETPAGEFLAG_NOOP(uname, lname) \ |
387 | static inline void folio_set_##lname(struct folio *folio) { } \ | |
8a7a8544 LS |
388 | static inline void SetPage##uname(struct page *page) { } |
389 | ||
d389a4a8 MWO |
390 | #define CLEARPAGEFLAG_NOOP(uname, lname) \ |
391 | static inline void folio_clear_##lname(struct folio *folio) { } \ | |
8a7a8544 LS |
392 | static inline void ClearPage##uname(struct page *page) { } |
393 | ||
d389a4a8 MWO |
394 | #define __CLEARPAGEFLAG_NOOP(uname, lname) \ |
395 | static inline void __folio_clear_##lname(struct folio *folio) { } \ | |
8a7a8544 LS |
396 | static inline void __ClearPage##uname(struct page *page) { } |
397 | ||
d389a4a8 MWO |
398 | #define TESTSETFLAG_FALSE(uname, lname) \ |
399 | static inline bool folio_test_set_##lname(struct folio *folio) \ | |
400 | { return 0; } \ | |
2f3e442c JW |
401 | static inline int TestSetPage##uname(struct page *page) { return 0; } |
402 | ||
d389a4a8 MWO |
403 | #define TESTCLEARFLAG_FALSE(uname, lname) \ |
404 | static inline bool folio_test_clear_##lname(struct folio *folio) \ | |
405 | { return 0; } \ | |
8a7a8544 LS |
406 | static inline int TestClearPage##uname(struct page *page) { return 0; } |
407 | ||
d389a4a8 MWO |
408 | #define PAGEFLAG_FALSE(uname, lname) TESTPAGEFLAG_FALSE(uname, lname) \ |
409 | SETPAGEFLAG_NOOP(uname, lname) CLEARPAGEFLAG_NOOP(uname, lname) | |
2f3e442c | 410 | |
d389a4a8 MWO |
411 | #define TESTSCFLAG_FALSE(uname, lname) \ |
412 | TESTSETFLAG_FALSE(uname, lname) TESTCLEARFLAG_FALSE(uname, lname) | |
2f3e442c | 413 | |
48c935ad | 414 | __PAGEFLAG(Locked, locked, PF_NO_TAIL) |
62906027 | 415 | PAGEFLAG(Waiters, waiters, PF_ONLY_HEAD) __CLEARPAGEFLAG(Waiters, waiters, PF_ONLY_HEAD) |
d72520ad | 416 | PAGEFLAG(Error, error, PF_NO_TAIL) TESTCLEARFLAG(Error, error, PF_NO_TAIL) |
8cb38fab KS |
417 | PAGEFLAG(Referenced, referenced, PF_HEAD) |
418 | TESTCLEARFLAG(Referenced, referenced, PF_HEAD) | |
419 | __SETPAGEFLAG(Referenced, referenced, PF_HEAD) | |
df8c94d1 KS |
420 | PAGEFLAG(Dirty, dirty, PF_HEAD) TESTSCFLAG(Dirty, dirty, PF_HEAD) |
421 | __CLEARPAGEFLAG(Dirty, dirty, PF_HEAD) | |
8cb38fab | 422 | PAGEFLAG(LRU, lru, PF_HEAD) __CLEARPAGEFLAG(LRU, lru, PF_HEAD) |
d25b5bd8 | 423 | TESTCLEARFLAG(LRU, lru, PF_HEAD) |
8cb38fab KS |
424 | PAGEFLAG(Active, active, PF_HEAD) __CLEARPAGEFLAG(Active, active, PF_HEAD) |
425 | TESTCLEARFLAG(Active, active, PF_HEAD) | |
1899ad18 JW |
426 | PAGEFLAG(Workingset, workingset, PF_HEAD) |
427 | TESTCLEARFLAG(Workingset, workingset, PF_HEAD) | |
dcb351cd KS |
428 | __PAGEFLAG(Slab, slab, PF_NO_TAIL) |
429 | __PAGEFLAG(SlobFree, slob_free, PF_NO_TAIL) | |
df8c94d1 | 430 | PAGEFLAG(Checked, checked, PF_NO_COMPOUND) /* Used by some filesystems */ |
c13985fa KS |
431 | |
432 | /* Xen */ | |
433 | PAGEFLAG(Pinned, pinned, PF_NO_COMPOUND) | |
434 | TESTSCFLAG(Pinned, pinned, PF_NO_COMPOUND) | |
435 | PAGEFLAG(SavePinned, savepinned, PF_NO_COMPOUND); | |
436 | PAGEFLAG(Foreign, foreign, PF_NO_COMPOUND); | |
b877ac98 JG |
437 | PAGEFLAG(XenRemapped, xen_remapped, PF_NO_COMPOUND) |
438 | TESTCLEARFLAG(XenRemapped, xen_remapped, PF_NO_COMPOUND) | |
c13985fa | 439 | |
de09d31d KS |
440 | PAGEFLAG(Reserved, reserved, PF_NO_COMPOUND) |
441 | __CLEARPAGEFLAG(Reserved, reserved, PF_NO_COMPOUND) | |
d483da5b | 442 | __SETPAGEFLAG(Reserved, reserved, PF_NO_COMPOUND) |
da5efc40 KS |
443 | PAGEFLAG(SwapBacked, swapbacked, PF_NO_TAIL) |
444 | __CLEARPAGEFLAG(SwapBacked, swapbacked, PF_NO_TAIL) | |
445 | __SETPAGEFLAG(SwapBacked, swapbacked, PF_NO_TAIL) | |
95ad9755 | 446 | |
266cf658 DH |
447 | /* |
448 | * Private page markings that may be used by the filesystem that owns the page | |
449 | * for its own purposes. | |
450 | * - PG_private and PG_private_2 cause releasepage() and co to be invoked | |
451 | */ | |
2ee08717 | 452 | PAGEFLAG(Private, private, PF_ANY) |
95ad9755 KS |
453 | PAGEFLAG(Private2, private_2, PF_ANY) TESTSCFLAG(Private2, private_2, PF_ANY) |
454 | PAGEFLAG(OwnerPriv1, owner_priv_1, PF_ANY) | |
455 | TESTCLEARFLAG(OwnerPriv1, owner_priv_1, PF_ANY) | |
266cf658 | 456 | |
6a1e7f77 CL |
457 | /* |
458 | * Only test-and-set exist for PG_writeback. The unconditional operators are | |
459 | * risky: they bypass page accounting. | |
460 | */ | |
225311a4 HY |
461 | TESTPAGEFLAG(Writeback, writeback, PF_NO_TAIL) |
462 | TESTSCFLAG(Writeback, writeback, PF_NO_TAIL) | |
e2f0a0db | 463 | PAGEFLAG(MappedToDisk, mappedtodisk, PF_NO_TAIL) |
6a1e7f77 | 464 | |
579f8290 | 465 | /* PG_readahead is only used for reads; PG_reclaim is only for writes */ |
e2f0a0db KS |
466 | PAGEFLAG(Reclaim, reclaim, PF_NO_TAIL) |
467 | TESTCLEARFLAG(Reclaim, reclaim, PF_NO_TAIL) | |
d389a4a8 MWO |
468 | PAGEFLAG(Readahead, readahead, PF_NO_COMPOUND) |
469 | TESTCLEARFLAG(Readahead, readahead, PF_NO_COMPOUND) | |
6a1e7f77 CL |
470 | |
471 | #ifdef CONFIG_HIGHMEM | |
1da177e4 | 472 | /* |
6a1e7f77 CL |
473 | * Must use a macro here due to header dependency issues. page_zone() is not |
474 | * available at this point. | |
1da177e4 | 475 | */ |
3ca65c19 | 476 | #define PageHighMem(__p) is_highmem_idx(page_zonenum(__p)) |
6a1e7f77 | 477 | #else |
d389a4a8 | 478 | PAGEFLAG_FALSE(HighMem, highmem) |
6a1e7f77 CL |
479 | #endif |
480 | ||
481 | #ifdef CONFIG_SWAP | |
d389a4a8 | 482 | static __always_inline bool folio_test_swapcache(struct folio *folio) |
6326fec1 | 483 | { |
d389a4a8 MWO |
484 | return folio_test_swapbacked(folio) && |
485 | test_bit(PG_swapcache, folio_flags(folio, 0)); | |
486 | } | |
6326fec1 | 487 | |
d389a4a8 MWO |
488 | static __always_inline bool PageSwapCache(struct page *page) |
489 | { | |
490 | return folio_test_swapcache(page_folio(page)); | |
6326fec1 | 491 | } |
d389a4a8 | 492 | |
38d8b4e6 HY |
493 | SETPAGEFLAG(SwapCache, swapcache, PF_NO_TAIL) |
494 | CLEARPAGEFLAG(SwapCache, swapcache, PF_NO_TAIL) | |
6a1e7f77 | 495 | #else |
d389a4a8 | 496 | PAGEFLAG_FALSE(SwapCache, swapcache) |
6a1e7f77 CL |
497 | #endif |
498 | ||
8cb38fab KS |
499 | PAGEFLAG(Unevictable, unevictable, PF_HEAD) |
500 | __CLEARPAGEFLAG(Unevictable, unevictable, PF_HEAD) | |
501 | TESTCLEARFLAG(Unevictable, unevictable, PF_HEAD) | |
b291f000 | 502 | |
af8e3354 | 503 | #ifdef CONFIG_MMU |
e4f87d5d KS |
504 | PAGEFLAG(Mlocked, mlocked, PF_NO_TAIL) |
505 | __CLEARPAGEFLAG(Mlocked, mlocked, PF_NO_TAIL) | |
506 | TESTSCFLAG(Mlocked, mlocked, PF_NO_TAIL) | |
894bc310 | 507 | #else |
d389a4a8 MWO |
508 | PAGEFLAG_FALSE(Mlocked, mlocked) __CLEARPAGEFLAG_NOOP(Mlocked, mlocked) |
509 | TESTSCFLAG_FALSE(Mlocked, mlocked) | |
894bc310 LS |
510 | #endif |
511 | ||
46cf98cd | 512 | #ifdef CONFIG_ARCH_USES_PG_UNCACHED |
b9d41817 | 513 | PAGEFLAG(Uncached, uncached, PF_NO_COMPOUND) |
602c4d11 | 514 | #else |
d389a4a8 | 515 | PAGEFLAG_FALSE(Uncached, uncached) |
6a1e7f77 | 516 | #endif |
1da177e4 | 517 | |
d466f2fc | 518 | #ifdef CONFIG_MEMORY_FAILURE |
95ad9755 KS |
519 | PAGEFLAG(HWPoison, hwpoison, PF_ANY) |
520 | TESTSCFLAG(HWPoison, hwpoison, PF_ANY) | |
d466f2fc | 521 | #define __PG_HWPOISON (1UL << PG_hwpoison) |
bf181c58 NH |
522 | #define MAGIC_HWPOISON 0x48575053U /* HWPS */ |
523 | extern void SetPageHWPoisonTakenOff(struct page *page); | |
524 | extern void ClearPageHWPoisonTakenOff(struct page *page); | |
06be6ff3 | 525 | extern bool take_page_off_buddy(struct page *page); |
bf181c58 | 526 | extern bool put_page_back_buddy(struct page *page); |
d466f2fc | 527 | #else |
d389a4a8 | 528 | PAGEFLAG_FALSE(HWPoison, hwpoison) |
d466f2fc AK |
529 | #define __PG_HWPOISON 0 |
530 | #endif | |
531 | ||
1c676e0d | 532 | #if defined(CONFIG_PAGE_IDLE_FLAG) && defined(CONFIG_64BIT) |
95ad9755 KS |
533 | TESTPAGEFLAG(Young, young, PF_ANY) |
534 | SETPAGEFLAG(Young, young, PF_ANY) | |
535 | TESTCLEARFLAG(Young, young, PF_ANY) | |
536 | PAGEFLAG(Idle, idle, PF_ANY) | |
33c3fc71 VD |
537 | #endif |
538 | ||
c275c5c6 PC |
539 | #ifdef CONFIG_KASAN_HW_TAGS |
540 | PAGEFLAG(SkipKASanPoison, skip_kasan_poison, PF_HEAD) | |
541 | #else | |
d389a4a8 | 542 | PAGEFLAG_FALSE(SkipKASanPoison, skip_kasan_poison) |
c275c5c6 PC |
543 | #endif |
544 | ||
36e66c55 AD |
545 | /* |
546 | * PageReported() is used to track reported free pages within the Buddy | |
547 | * allocator. We can use the non-atomic version of the test and set | |
548 | * operations as both should be shielded with the zone lock to prevent | |
549 | * any possible races on the setting or clearing of the bit. | |
550 | */ | |
551 | __PAGEFLAG(Reported, reported, PF_NO_COMPOUND) | |
552 | ||
e8c6158f KS |
553 | /* |
554 | * On an anonymous page mapped into a user virtual memory area, | |
555 | * page->mapping points to its anon_vma, not to a struct address_space; | |
556 | * with the PAGE_MAPPING_ANON bit set to distinguish it. See rmap.h. | |
557 | * | |
558 | * On an anonymous page in a VM_MERGEABLE area, if CONFIG_KSM is enabled, | |
bda807d4 MK |
559 | * the PAGE_MAPPING_MOVABLE bit may be set along with the PAGE_MAPPING_ANON |
560 | * bit; and then page->mapping points, not to an anon_vma, but to a private | |
e8c6158f KS |
561 | * structure which KSM associates with that merged page. See ksm.h. |
562 | * | |
bda807d4 MK |
563 | * PAGE_MAPPING_KSM without PAGE_MAPPING_ANON is used for non-lru movable |
564 | * page and then page->mapping points a struct address_space. | |
e8c6158f KS |
565 | * |
566 | * Please note that, confusingly, "page_mapping" refers to the inode | |
567 | * address_space which maps the page from disk; whereas "page_mapped" | |
568 | * refers to user virtual address space into which the page is mapped. | |
569 | */ | |
bda807d4 MK |
570 | #define PAGE_MAPPING_ANON 0x1 |
571 | #define PAGE_MAPPING_MOVABLE 0x2 | |
572 | #define PAGE_MAPPING_KSM (PAGE_MAPPING_ANON | PAGE_MAPPING_MOVABLE) | |
573 | #define PAGE_MAPPING_FLAGS (PAGE_MAPPING_ANON | PAGE_MAPPING_MOVABLE) | |
e8c6158f | 574 | |
bda807d4 | 575 | static __always_inline int PageMappingFlags(struct page *page) |
17514574 | 576 | { |
bda807d4 | 577 | return ((unsigned long)page->mapping & PAGE_MAPPING_FLAGS) != 0; |
17514574 MG |
578 | } |
579 | ||
d389a4a8 | 580 | static __always_inline bool folio_test_anon(struct folio *folio) |
e8c6158f | 581 | { |
d389a4a8 MWO |
582 | return ((unsigned long)folio->mapping & PAGE_MAPPING_ANON) != 0; |
583 | } | |
584 | ||
585 | static __always_inline bool PageAnon(struct page *page) | |
e8c6158f | 586 | { |
d389a4a8 | 587 | return folio_test_anon(page_folio(page)); |
bda807d4 MK |
588 | } |
589 | ||
590 | static __always_inline int __PageMovable(struct page *page) | |
591 | { | |
592 | return ((unsigned long)page->mapping & PAGE_MAPPING_FLAGS) == | |
593 | PAGE_MAPPING_MOVABLE; | |
e8c6158f KS |
594 | } |
595 | ||
596 | #ifdef CONFIG_KSM | |
597 | /* | |
598 | * A KSM page is one of those write-protected "shared pages" or "merged pages" | |
599 | * which KSM maps into multiple mms, wherever identical anonymous page content | |
600 | * is found in VM_MERGEABLE vmas. It's a PageAnon page, pointing not to any | |
601 | * anon_vma, but to that page's node of the stable tree. | |
602 | */ | |
d389a4a8 | 603 | static __always_inline bool folio_test_ksm(struct folio *folio) |
e8c6158f | 604 | { |
d389a4a8 | 605 | return ((unsigned long)folio->mapping & PAGE_MAPPING_FLAGS) == |
bda807d4 | 606 | PAGE_MAPPING_KSM; |
e8c6158f | 607 | } |
d389a4a8 MWO |
608 | |
609 | static __always_inline bool PageKsm(struct page *page) | |
610 | { | |
611 | return folio_test_ksm(page_folio(page)); | |
612 | } | |
e8c6158f | 613 | #else |
d389a4a8 | 614 | TESTPAGEFLAG_FALSE(Ksm, ksm) |
e8c6158f KS |
615 | #endif |
616 | ||
1a9b5b7f WF |
617 | u64 stable_page_flags(struct page *page); |
618 | ||
ece01414 MWO |
619 | /** |
620 | * folio_test_uptodate - Is this folio up to date? | |
621 | * @folio: The folio. | |
622 | * | |
623 | * The uptodate flag is set on a folio when every byte in the folio is | |
624 | * at least as new as the corresponding bytes on storage. Anonymous | |
625 | * and CoW folios are always uptodate. If the folio is not uptodate, | |
626 | * some of the bytes in it may be; see the is_partially_uptodate() | |
627 | * address_space operation. | |
628 | */ | |
d389a4a8 | 629 | static inline bool folio_test_uptodate(struct folio *folio) |
0ed361de | 630 | { |
d389a4a8 | 631 | bool ret = test_bit(PG_uptodate, folio_flags(folio, 0)); |
0ed361de | 632 | /* |
d389a4a8 MWO |
633 | * Must ensure that the data we read out of the folio is loaded |
634 | * _after_ we've loaded folio->flags to check the uptodate bit. | |
635 | * We can skip the barrier if the folio is not uptodate, because | |
0ed361de NP |
636 | * we wouldn't be reading anything from it. |
637 | * | |
d389a4a8 | 638 | * See folio_mark_uptodate() for the other side of the story. |
0ed361de NP |
639 | */ |
640 | if (ret) | |
641 | smp_rmb(); | |
642 | ||
643 | return ret; | |
644 | } | |
645 | ||
d389a4a8 MWO |
646 | static inline int PageUptodate(struct page *page) |
647 | { | |
648 | return folio_test_uptodate(page_folio(page)); | |
649 | } | |
650 | ||
651 | static __always_inline void __folio_mark_uptodate(struct folio *folio) | |
0ed361de NP |
652 | { |
653 | smp_wmb(); | |
d389a4a8 | 654 | __set_bit(PG_uptodate, folio_flags(folio, 0)); |
0ed361de NP |
655 | } |
656 | ||
d389a4a8 | 657 | static __always_inline void folio_mark_uptodate(struct folio *folio) |
2dcea57a | 658 | { |
0ed361de NP |
659 | /* |
660 | * Memory barrier must be issued before setting the PG_uptodate bit, | |
d389a4a8 MWO |
661 | * so that all previous stores issued in order to bring the folio |
662 | * uptodate are actually visible before folio_test_uptodate becomes true. | |
0ed361de NP |
663 | */ |
664 | smp_wmb(); | |
d389a4a8 MWO |
665 | set_bit(PG_uptodate, folio_flags(folio, 0)); |
666 | } | |
667 | ||
668 | static __always_inline void __SetPageUptodate(struct page *page) | |
669 | { | |
670 | __folio_mark_uptodate((struct folio *)page); | |
671 | } | |
672 | ||
673 | static __always_inline void SetPageUptodate(struct page *page) | |
674 | { | |
675 | folio_mark_uptodate((struct folio *)page); | |
0ed361de NP |
676 | } |
677 | ||
d2998c4d | 678 | CLEARPAGEFLAG(Uptodate, uptodate, PF_NO_TAIL) |
1da177e4 | 679 | |
f143f1ea MWO |
680 | bool __folio_start_writeback(struct folio *folio, bool keep_write); |
681 | bool set_page_writeback(struct page *page); | |
1c8349a1 | 682 | |
f143f1ea MWO |
683 | #define folio_start_writeback(folio) \ |
684 | __folio_start_writeback(folio, false) | |
685 | #define folio_start_writeback_keepwrite(folio) \ | |
686 | __folio_start_writeback(folio, true) | |
1da177e4 | 687 | |
f143f1ea | 688 | static inline void set_page_writeback_keepwrite(struct page *page) |
6a1e7f77 | 689 | { |
f143f1ea | 690 | folio_start_writeback_keepwrite(page_folio(page)); |
6a1e7f77 | 691 | } |
1da177e4 | 692 | |
f143f1ea | 693 | static inline bool test_set_page_writeback(struct page *page) |
1c8349a1 | 694 | { |
f143f1ea | 695 | return set_page_writeback(page); |
1c8349a1 NJ |
696 | } |
697 | ||
95ad9755 | 698 | __PAGEFLAG(Head, head, PF_ANY) CLEARPAGEFLAG(Head, head, PF_ANY) |
e20b8cca | 699 | |
9c325215 MWO |
700 | /** |
701 | * folio_test_large() - Does this folio contain more than one page? | |
702 | * @folio: The folio to test. | |
703 | * | |
704 | * Return: True if the folio is larger than one page. | |
705 | */ | |
706 | static inline bool folio_test_large(struct folio *folio) | |
d389a4a8 MWO |
707 | { |
708 | return folio_test_head(folio); | |
709 | } | |
710 | ||
4b0f3261 | 711 | static __always_inline void set_compound_head(struct page *page, struct page *head) |
ad4b3fb7 | 712 | { |
1d798ca3 | 713 | WRITE_ONCE(page->compound_head, (unsigned long)head + 1); |
ad4b3fb7 CD |
714 | } |
715 | ||
4b0f3261 | 716 | static __always_inline void clear_compound_head(struct page *page) |
6a1e7f77 | 717 | { |
1d798ca3 | 718 | WRITE_ONCE(page->compound_head, 0); |
6a1e7f77 | 719 | } |
6d777953 | 720 | |
4e6af67e AA |
721 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
722 | static inline void ClearPageCompound(struct page *page) | |
723 | { | |
1d798ca3 KS |
724 | BUG_ON(!PageHead(page)); |
725 | ClearPageHead(page); | |
4e6af67e AA |
726 | } |
727 | #endif | |
728 | ||
d2a1a1f0 | 729 | #define PG_head_mask ((1UL << PG_head)) |
dfa7e20c | 730 | |
e8c6158f KS |
731 | #ifdef CONFIG_HUGETLB_PAGE |
732 | int PageHuge(struct page *page); | |
733 | int PageHeadHuge(struct page *page); | |
d389a4a8 MWO |
734 | static inline bool folio_test_hugetlb(struct folio *folio) |
735 | { | |
736 | return PageHeadHuge(&folio->page); | |
737 | } | |
e8c6158f | 738 | #else |
d389a4a8 MWO |
739 | TESTPAGEFLAG_FALSE(Huge, hugetlb) |
740 | TESTPAGEFLAG_FALSE(HeadHuge, headhuge) | |
e8c6158f KS |
741 | #endif |
742 | ||
936a5fe6 | 743 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
71e3aac0 AA |
744 | /* |
745 | * PageHuge() only returns true for hugetlbfs pages, but not for | |
746 | * normal or transparent huge pages. | |
747 | * | |
748 | * PageTransHuge() returns true for both transparent huge and | |
749 | * hugetlbfs pages, but not normal pages. PageTransHuge() can only be | |
750 | * called only in the core VM paths where hugetlbfs pages can't exist. | |
751 | */ | |
752 | static inline int PageTransHuge(struct page *page) | |
753 | { | |
309381fe | 754 | VM_BUG_ON_PAGE(PageTail(page), page); |
71e3aac0 AA |
755 | return PageHead(page); |
756 | } | |
757 | ||
d389a4a8 MWO |
758 | static inline bool folio_test_transhuge(struct folio *folio) |
759 | { | |
760 | return folio_test_head(folio); | |
761 | } | |
762 | ||
385de357 DN |
763 | /* |
764 | * PageTransCompound returns true for both transparent huge pages | |
765 | * and hugetlbfs pages, so it should only be called when it's known | |
766 | * that hugetlbfs pages aren't involved. | |
767 | */ | |
936a5fe6 AA |
768 | static inline int PageTransCompound(struct page *page) |
769 | { | |
770 | return PageCompound(page); | |
771 | } | |
71e3aac0 | 772 | |
385de357 DN |
773 | /* |
774 | * PageTransTail returns true for both transparent huge pages | |
775 | * and hugetlbfs pages, so it should only be called when it's known | |
776 | * that hugetlbfs pages aren't involved. | |
777 | */ | |
778 | static inline int PageTransTail(struct page *page) | |
779 | { | |
780 | return PageTail(page); | |
781 | } | |
782 | ||
53f9263b KS |
783 | /* |
784 | * PageDoubleMap indicates that the compound page is mapped with PTEs as well | |
785 | * as PMDs. | |
786 | * | |
787 | * This is required for optimization of rmap operations for THP: we can postpone | |
788 | * per small page mapcount accounting (and its overhead from atomic operations) | |
789 | * until the first PMD split. | |
790 | * | |
791 | * For the page PageDoubleMap means ->_mapcount in all sub-pages is offset up | |
792 | * by one. This reference will go away with last compound_mapcount. | |
793 | * | |
794 | * See also __split_huge_pmd_locked() and page_remove_anon_compound_rmap(). | |
795 | */ | |
a08d93e5 MWO |
796 | PAGEFLAG(DoubleMap, double_map, PF_SECOND) |
797 | TESTSCFLAG(DoubleMap, double_map, PF_SECOND) | |
936a5fe6 | 798 | #else |
d389a4a8 MWO |
799 | TESTPAGEFLAG_FALSE(TransHuge, transhuge) |
800 | TESTPAGEFLAG_FALSE(TransCompound, transcompound) | |
801 | TESTPAGEFLAG_FALSE(TransCompoundMap, transcompoundmap) | |
802 | TESTPAGEFLAG_FALSE(TransTail, transtail) | |
803 | PAGEFLAG_FALSE(DoubleMap, double_map) | |
804 | TESTSCFLAG_FALSE(DoubleMap, double_map) | |
936a5fe6 AA |
805 | #endif |
806 | ||
eac96c3e YS |
807 | #if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_TRANSPARENT_HUGEPAGE) |
808 | /* | |
809 | * PageHasHWPoisoned indicates that at least one subpage is hwpoisoned in the | |
810 | * compound page. | |
811 | * | |
812 | * This flag is set by hwpoison handler. Cleared by THP split or free page. | |
813 | */ | |
814 | PAGEFLAG(HasHWPoisoned, has_hwpoisoned, PF_SECOND) | |
815 | TESTSCFLAG(HasHWPoisoned, has_hwpoisoned, PF_SECOND) | |
816 | #else | |
e6643593 LT |
817 | PAGEFLAG_FALSE(HasHWPoisoned, has_hwpoisoned) |
818 | TESTSCFLAG_FALSE(HasHWPoisoned, has_hwpoisoned) | |
eac96c3e YS |
819 | #endif |
820 | ||
0daa322b DH |
821 | /* |
822 | * Check if a page is currently marked HWPoisoned. Note that this check is | |
823 | * best effort only and inherently racy: there is no way to synchronize with | |
824 | * failing hardware. | |
825 | */ | |
826 | static inline bool is_page_hwpoison(struct page *page) | |
827 | { | |
828 | if (PageHWPoison(page)) | |
829 | return true; | |
830 | return PageHuge(page) && PageHWPoison(compound_head(page)); | |
831 | } | |
832 | ||
e8c6158f | 833 | /* |
6e292b9b MW |
834 | * For pages that are never mapped to userspace (and aren't PageSlab), |
835 | * page_type may be used. Because it is initialised to -1, we invert the | |
836 | * sense of the bit, so __SetPageFoo *clears* the bit used for PageFoo, and | |
837 | * __ClearPageFoo *sets* the bit used for PageFoo. We reserve a few high and | |
838 | * low bits so that an underflow or overflow of page_mapcount() won't be | |
839 | * mistaken for a page type value. | |
e8c6158f | 840 | */ |
6e292b9b MW |
841 | |
842 | #define PAGE_TYPE_BASE 0xf0000000 | |
843 | /* Reserve 0x0000007f to catch underflows of page_mapcount */ | |
144552ff | 844 | #define PAGE_MAPCOUNT_RESERVE -128 |
6e292b9b | 845 | #define PG_buddy 0x00000080 |
ca215086 | 846 | #define PG_offline 0x00000100 |
18b2db3b RG |
847 | #define PG_table 0x00000200 |
848 | #define PG_guard 0x00000400 | |
6e292b9b MW |
849 | |
850 | #define PageType(page, flag) \ | |
851 | ((page->page_type & (PAGE_TYPE_BASE | flag)) == PAGE_TYPE_BASE) | |
852 | ||
144552ff AY |
853 | static inline int page_has_type(struct page *page) |
854 | { | |
855 | return (int)page->page_type < PAGE_MAPCOUNT_RESERVE; | |
856 | } | |
857 | ||
6e292b9b | 858 | #define PAGE_TYPE_OPS(uname, lname) \ |
632c0a1a VD |
859 | static __always_inline int Page##uname(struct page *page) \ |
860 | { \ | |
6e292b9b | 861 | return PageType(page, PG_##lname); \ |
632c0a1a VD |
862 | } \ |
863 | static __always_inline void __SetPage##uname(struct page *page) \ | |
864 | { \ | |
6e292b9b MW |
865 | VM_BUG_ON_PAGE(!PageType(page, 0), page); \ |
866 | page->page_type &= ~PG_##lname; \ | |
632c0a1a VD |
867 | } \ |
868 | static __always_inline void __ClearPage##uname(struct page *page) \ | |
869 | { \ | |
870 | VM_BUG_ON_PAGE(!Page##uname(page), page); \ | |
6e292b9b | 871 | page->page_type |= PG_##lname; \ |
e8c6158f KS |
872 | } |
873 | ||
632c0a1a | 874 | /* |
6e292b9b | 875 | * PageBuddy() indicates that the page is free and in the buddy system |
632c0a1a VD |
876 | * (see mm/page_alloc.c). |
877 | */ | |
6e292b9b | 878 | PAGE_TYPE_OPS(Buddy, buddy) |
e8c6158f | 879 | |
632c0a1a | 880 | /* |
ca215086 DH |
881 | * PageOffline() indicates that the page is logically offline although the |
882 | * containing section is online. (e.g. inflated in a balloon driver or | |
883 | * not onlined when onlining the section). | |
884 | * The content of these pages is effectively stale. Such pages should not | |
885 | * be touched (read/write/dump/save) except by their owner. | |
aa218795 DH |
886 | * |
887 | * If a driver wants to allow to offline unmovable PageOffline() pages without | |
888 | * putting them back to the buddy, it can do so via the memory notifier by | |
889 | * decrementing the reference count in MEM_GOING_OFFLINE and incrementing the | |
890 | * reference count in MEM_CANCEL_OFFLINE. When offlining, the PageOffline() | |
891 | * pages (now with a reference count of zero) are treated like free pages, | |
892 | * allowing the containing memory block to get offlined. A driver that | |
893 | * relies on this feature is aware that re-onlining the memory block will | |
894 | * require to re-set the pages PageOffline() and not giving them to the | |
895 | * buddy via online_page_callback_t. | |
82840451 DH |
896 | * |
897 | * There are drivers that mark a page PageOffline() and expect there won't be | |
898 | * any further access to page content. PFN walkers that read content of random | |
899 | * pages should check PageOffline() and synchronize with such drivers using | |
900 | * page_offline_freeze()/page_offline_thaw(). | |
632c0a1a | 901 | */ |
ca215086 | 902 | PAGE_TYPE_OPS(Offline, offline) |
e8c6158f | 903 | |
82840451 DH |
904 | extern void page_offline_freeze(void); |
905 | extern void page_offline_thaw(void); | |
906 | extern void page_offline_begin(void); | |
907 | extern void page_offline_end(void); | |
908 | ||
1d40a5ea MW |
909 | /* |
910 | * Marks pages in use as page tables. | |
911 | */ | |
912 | PAGE_TYPE_OPS(Table, table) | |
913 | ||
3972f6bb VB |
914 | /* |
915 | * Marks guardpages used with debug_pagealloc. | |
916 | */ | |
917 | PAGE_TYPE_OPS(Guard, guard) | |
918 | ||
832fc1de NH |
919 | extern bool is_free_buddy_page(struct page *page); |
920 | ||
bda807d4 MK |
921 | __PAGEFLAG(Isolated, isolated, PF_ANY); |
922 | ||
af8e3354 | 923 | #ifdef CONFIG_MMU |
d2a1a1f0 | 924 | #define __PG_MLOCKED (1UL << PG_mlocked) |
33925b25 | 925 | #else |
b291f000 | 926 | #define __PG_MLOCKED 0 |
894bc310 LS |
927 | #endif |
928 | ||
dfa7e20c RA |
929 | /* |
930 | * Flags checked when a page is freed. Pages being freed should not have | |
4be408ce | 931 | * these flags set. If they are, there is a problem. |
dfa7e20c | 932 | */ |
6326fec1 NP |
933 | #define PAGE_FLAGS_CHECK_AT_FREE \ |
934 | (1UL << PG_lru | 1UL << PG_locked | \ | |
935 | 1UL << PG_private | 1UL << PG_private_2 | \ | |
936 | 1UL << PG_writeback | 1UL << PG_reserved | \ | |
937 | 1UL << PG_slab | 1UL << PG_active | \ | |
938 | 1UL << PG_unevictable | __PG_MLOCKED) | |
dfa7e20c RA |
939 | |
940 | /* | |
941 | * Flags checked when a page is prepped for return by the page allocator. | |
4be408ce | 942 | * Pages being prepped should not have these flags set. If they are set, |
79f4b7bf | 943 | * there has been a kernel bug or struct page corruption. |
f4c18e6f NH |
944 | * |
945 | * __PG_HWPOISON is exceptional because it needs to be kept beyond page's | |
946 | * alloc-free cycle to prevent from reusing the page. | |
dfa7e20c | 947 | */ |
f4c18e6f | 948 | #define PAGE_FLAGS_CHECK_AT_PREP \ |
41c961b9 | 949 | (PAGEFLAGS_MASK & ~__PG_HWPOISON) |
dfa7e20c | 950 | |
edcf4748 | 951 | #define PAGE_FLAGS_PRIVATE \ |
d2a1a1f0 | 952 | (1UL << PG_private | 1UL << PG_private_2) |
266cf658 DH |
953 | /** |
954 | * page_has_private - Determine if page has private stuff | |
955 | * @page: The page to be checked | |
956 | * | |
957 | * Determine if a page has private stuff, indicating that release routines | |
958 | * should be invoked upon it. | |
959 | */ | |
edcf4748 JW |
960 | static inline int page_has_private(struct page *page) |
961 | { | |
962 | return !!(page->flags & PAGE_FLAGS_PRIVATE); | |
963 | } | |
964 | ||
d389a4a8 MWO |
965 | static inline bool folio_has_private(struct folio *folio) |
966 | { | |
967 | return page_has_private(&folio->page); | |
968 | } | |
969 | ||
95ad9755 KS |
970 | #undef PF_ANY |
971 | #undef PF_HEAD | |
62906027 | 972 | #undef PF_ONLY_HEAD |
95ad9755 KS |
973 | #undef PF_NO_TAIL |
974 | #undef PF_NO_COMPOUND | |
a08d93e5 | 975 | #undef PF_SECOND |
edcf4748 | 976 | #endif /* !__GENERATING_BOUNDS_H */ |
266cf658 | 977 | |
1da177e4 | 978 | #endif /* PAGE_FLAGS_H */ |