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 | * | |
1da177e4 LT |
71 | * PG_uptodate tells whether the page's contents is valid. When a read |
72 | * completes, the page becomes uptodate, unless a disk I/O error happened. | |
73 | * | |
da6052f7 NP |
74 | * PG_referenced, PG_reclaim are used for page reclaim for anonymous and |
75 | * file-backed pagecache (see mm/vmscan.c). | |
1da177e4 LT |
76 | * |
77 | * PG_error is set to indicate that an I/O error occurred on this page. | |
78 | * | |
79 | * PG_arch_1 is an architecture specific page state bit. The generic code | |
80 | * guarantees that this bit is cleared for a page when it first is entered into | |
81 | * the page cache. | |
82 | * | |
d466f2fc AK |
83 | * PG_hwpoison indicates that a page got corrupted in hardware and contains |
84 | * data with incorrect ECC bits that triggered a machine check. Accessing is | |
85 | * not safe since it may cause another machine check. Don't touch! | |
1da177e4 LT |
86 | */ |
87 | ||
88 | /* | |
3b12da6d | 89 | * Don't use the pageflags directly. Use the PageFoo macros. |
91fc8ab3 AW |
90 | * |
91 | * The page flags field is split into two parts, the main flags area | |
92 | * which extends from the low bits upwards, and the fields area which | |
93 | * extends from the high bits downwards. | |
94 | * | |
95 | * | FIELD | ... | FLAGS | | |
9223b419 CL |
96 | * N-1 ^ 0 |
97 | * (NR_PAGEFLAGS) | |
91fc8ab3 | 98 | * |
9223b419 CL |
99 | * The fields area is reserved for fields mapping zone, node (for NUMA) and |
100 | * SPARSEMEM section (for variants of SPARSEMEM that require section ids like | |
101 | * SPARSEMEM_EXTREME with !SPARSEMEM_VMEMMAP). | |
1da177e4 | 102 | */ |
e2683181 CL |
103 | enum pageflags { |
104 | PG_locked, /* Page is locked. Don't touch. */ | |
e2683181 CL |
105 | PG_referenced, |
106 | PG_uptodate, | |
107 | PG_dirty, | |
108 | PG_lru, | |
109 | PG_active, | |
1899ad18 | 110 | PG_workingset, |
b91e1302 | 111 | PG_waiters, /* Page has waiters, check its waitqueue. Must be bit #7 and in the same byte as "PG_locked" */ |
1899ad18 | 112 | PG_error, |
e2683181 CL |
113 | PG_slab, |
114 | PG_owner_priv_1, /* Owner use. If pagecache, fs may use*/ | |
e2683181 CL |
115 | PG_arch_1, |
116 | PG_reserved, | |
117 | PG_private, /* If pagecache, has fs-private data */ | |
266cf658 | 118 | PG_private_2, /* If pagecache, has fs aux data */ |
e2683181 | 119 | PG_writeback, /* Page is under writeback */ |
e20b8cca | 120 | PG_head, /* A head page */ |
e2683181 CL |
121 | PG_mappedtodisk, /* Has blocks allocated on-disk */ |
122 | PG_reclaim, /* To be reclaimed asap */ | |
b2e18538 | 123 | PG_swapbacked, /* Page is backed by RAM/swap */ |
894bc310 | 124 | PG_unevictable, /* Page is "unevictable" */ |
af8e3354 | 125 | #ifdef CONFIG_MMU |
b291f000 | 126 | PG_mlocked, /* Page is vma mlocked */ |
894bc310 | 127 | #endif |
46cf98cd | 128 | #ifdef CONFIG_ARCH_USES_PG_UNCACHED |
602c4d11 | 129 | PG_uncached, /* Page has been mapped as uncached */ |
d466f2fc AK |
130 | #endif |
131 | #ifdef CONFIG_MEMORY_FAILURE | |
132 | PG_hwpoison, /* hardware poisoned page. Don't touch */ | |
e9da73d6 | 133 | #endif |
1c676e0d | 134 | #if defined(CONFIG_PAGE_IDLE_FLAG) && defined(CONFIG_64BIT) |
33c3fc71 VD |
135 | PG_young, |
136 | PG_idle, | |
4beba948 SP |
137 | #endif |
138 | #ifdef CONFIG_64BIT | |
139 | PG_arch_2, | |
c275c5c6 PC |
140 | #endif |
141 | #ifdef CONFIG_KASAN_HW_TAGS | |
142 | PG_skip_kasan_poison, | |
f886ed44 | 143 | #endif |
0cad47cf AW |
144 | __NR_PAGEFLAGS, |
145 | ||
d389a4a8 MWO |
146 | PG_readahead = PG_reclaim, |
147 | ||
0cad47cf AW |
148 | /* Filesystems */ |
149 | PG_checked = PG_owner_priv_1, | |
150 | ||
6326fec1 NP |
151 | /* SwapBacked */ |
152 | PG_swapcache = PG_owner_priv_1, /* Swap page: swp_entry_t in private */ | |
153 | ||
266cf658 DH |
154 | /* Two page bits are conscripted by FS-Cache to maintain local caching |
155 | * state. These bits are set on pages belonging to the netfs's inodes | |
156 | * when those inodes are being locally cached. | |
157 | */ | |
158 | PG_fscache = PG_private_2, /* page backed by cache */ | |
159 | ||
0cad47cf | 160 | /* XEN */ |
d8ac3dd4 | 161 | /* Pinned in Xen as a read-only pagetable page. */ |
0cad47cf | 162 | PG_pinned = PG_owner_priv_1, |
d8ac3dd4 | 163 | /* Pinned as part of domain save (see xen_mm_pin_all()). */ |
0cad47cf | 164 | PG_savepinned = PG_dirty, |
d8ac3dd4 JH |
165 | /* Has a grant mapping of another (foreign) domain's page. */ |
166 | PG_foreign = PG_owner_priv_1, | |
b877ac98 JG |
167 | /* Remapped by swiotlb-xen. */ |
168 | PG_xen_remapped = PG_owner_priv_1, | |
8a38082d | 169 | |
9023cb7e | 170 | /* SLOB */ |
9023cb7e | 171 | PG_slob_free = PG_private, |
53f9263b KS |
172 | |
173 | /* Compound pages. Stored in first tail page's flags */ | |
e18c45ff | 174 | PG_double_map = PG_workingset, |
bda807d4 | 175 | |
eac96c3e YS |
176 | #ifdef CONFIG_MEMORY_FAILURE |
177 | /* | |
178 | * Compound pages. Stored in first tail page's flags. | |
179 | * Indicates that at least one subpage is hwpoisoned in the | |
180 | * THP. | |
181 | */ | |
182 | PG_has_hwpoisoned = PG_mappedtodisk, | |
183 | #endif | |
184 | ||
bda807d4 MK |
185 | /* non-lru isolated movable page */ |
186 | PG_isolated = PG_reclaim, | |
36e66c55 AD |
187 | |
188 | /* Only valid for buddy pages. Used to track pages that are reported */ | |
189 | PG_reported = PG_uptodate, | |
e2683181 | 190 | }; |
1da177e4 | 191 | |
41c961b9 MS |
192 | #define PAGEFLAGS_MASK ((1UL << NR_PAGEFLAGS) - 1) |
193 | ||
9223b419 CL |
194 | #ifndef __GENERATING_BOUNDS_H |
195 | ||
0f2317e3 | 196 | static inline unsigned long _compound_head(const struct page *page) |
0e6d31a7 KS |
197 | { |
198 | unsigned long head = READ_ONCE(page->compound_head); | |
199 | ||
200 | if (unlikely(head & 1)) | |
0f2317e3 MWO |
201 | return head - 1; |
202 | return (unsigned long)page; | |
0e6d31a7 KS |
203 | } |
204 | ||
0f2317e3 MWO |
205 | #define compound_head(page) ((typeof(page))_compound_head(page)) |
206 | ||
7b230db3 MWO |
207 | /** |
208 | * page_folio - Converts from page to folio. | |
209 | * @p: The page. | |
210 | * | |
211 | * Every page is part of a folio. This function cannot be called on a | |
212 | * NULL pointer. | |
213 | * | |
214 | * Context: No reference, nor lock is required on @page. If the caller | |
215 | * does not hold a reference, this call may race with a folio split, so | |
216 | * it should re-check the folio still contains this page after gaining | |
217 | * a reference on the folio. | |
218 | * Return: The folio which contains this page. | |
219 | */ | |
220 | #define page_folio(p) (_Generic((p), \ | |
221 | const struct page *: (const struct folio *)_compound_head(p), \ | |
222 | struct page *: (struct folio *)_compound_head(p))) | |
223 | ||
224 | /** | |
225 | * folio_page - Return a page from a folio. | |
226 | * @folio: The folio. | |
227 | * @n: The page number to return. | |
228 | * | |
229 | * @n is relative to the start of the folio. This function does not | |
230 | * check that the page number lies within @folio; the caller is presumed | |
231 | * to have a reference to the page. | |
232 | */ | |
233 | #define folio_page(folio, n) nth_page(&(folio)->page, n) | |
234 | ||
4b0f3261 | 235 | static __always_inline int PageTail(struct page *page) |
0e6d31a7 KS |
236 | { |
237 | return READ_ONCE(page->compound_head) & 1; | |
238 | } | |
239 | ||
4b0f3261 | 240 | static __always_inline int PageCompound(struct page *page) |
0e6d31a7 KS |
241 | { |
242 | return test_bit(PG_head, &page->flags) || PageTail(page); | |
243 | } | |
244 | ||
f165b378 PT |
245 | #define PAGE_POISON_PATTERN -1l |
246 | static inline int PagePoisoned(const struct page *page) | |
247 | { | |
248 | return page->flags == PAGE_POISON_PATTERN; | |
249 | } | |
250 | ||
f682a97a AD |
251 | #ifdef CONFIG_DEBUG_VM |
252 | void page_init_poison(struct page *page, size_t size); | |
253 | #else | |
254 | static inline void page_init_poison(struct page *page, size_t size) | |
255 | { | |
256 | } | |
257 | #endif | |
258 | ||
d389a4a8 MWO |
259 | static unsigned long *folio_flags(struct folio *folio, unsigned n) |
260 | { | |
261 | struct page *page = &folio->page; | |
262 | ||
263 | VM_BUG_ON_PGFLAGS(PageTail(page), page); | |
264 | VM_BUG_ON_PGFLAGS(n > 0 && !test_bit(PG_head, &page->flags), page); | |
265 | return &page[n].flags; | |
266 | } | |
267 | ||
95ad9755 KS |
268 | /* |
269 | * Page flags policies wrt compound pages | |
270 | * | |
f165b378 PT |
271 | * PF_POISONED_CHECK |
272 | * check if this struct page poisoned/uninitialized | |
273 | * | |
95ad9755 KS |
274 | * PF_ANY: |
275 | * the page flag is relevant for small, head and tail pages. | |
276 | * | |
277 | * PF_HEAD: | |
278 | * for compound page all operations related to the page flag applied to | |
279 | * head page. | |
280 | * | |
62906027 NP |
281 | * PF_ONLY_HEAD: |
282 | * for compound page, callers only ever operate on the head page. | |
283 | * | |
95ad9755 KS |
284 | * PF_NO_TAIL: |
285 | * modifications of the page flag must be done on small or head pages, | |
286 | * checks can be done on tail pages too. | |
287 | * | |
288 | * PF_NO_COMPOUND: | |
289 | * the page flag is not relevant for compound pages. | |
a08d93e5 MWO |
290 | * |
291 | * PF_SECOND: | |
292 | * the page flag is stored in the first tail page. | |
95ad9755 | 293 | */ |
f165b378 PT |
294 | #define PF_POISONED_CHECK(page) ({ \ |
295 | VM_BUG_ON_PGFLAGS(PagePoisoned(page), page); \ | |
296 | page; }) | |
297 | #define PF_ANY(page, enforce) PF_POISONED_CHECK(page) | |
298 | #define PF_HEAD(page, enforce) PF_POISONED_CHECK(compound_head(page)) | |
62906027 NP |
299 | #define PF_ONLY_HEAD(page, enforce) ({ \ |
300 | VM_BUG_ON_PGFLAGS(PageTail(page), page); \ | |
f165b378 | 301 | PF_POISONED_CHECK(page); }) |
95ad9755 KS |
302 | #define PF_NO_TAIL(page, enforce) ({ \ |
303 | VM_BUG_ON_PGFLAGS(enforce && PageTail(page), page); \ | |
f165b378 | 304 | PF_POISONED_CHECK(compound_head(page)); }) |
822cdd11 | 305 | #define PF_NO_COMPOUND(page, enforce) ({ \ |
95ad9755 | 306 | VM_BUG_ON_PGFLAGS(enforce && PageCompound(page), page); \ |
f165b378 | 307 | PF_POISONED_CHECK(page); }) |
a08d93e5 MWO |
308 | #define PF_SECOND(page, enforce) ({ \ |
309 | VM_BUG_ON_PGFLAGS(!PageHead(page), page); \ | |
310 | PF_POISONED_CHECK(&page[1]); }) | |
95ad9755 | 311 | |
d389a4a8 MWO |
312 | /* Which page is the flag stored in */ |
313 | #define FOLIO_PF_ANY 0 | |
314 | #define FOLIO_PF_HEAD 0 | |
315 | #define FOLIO_PF_ONLY_HEAD 0 | |
316 | #define FOLIO_PF_NO_TAIL 0 | |
317 | #define FOLIO_PF_NO_COMPOUND 0 | |
318 | #define FOLIO_PF_SECOND 1 | |
319 | ||
f94a62e9 CL |
320 | /* |
321 | * Macros to create function definitions for page flags | |
322 | */ | |
95ad9755 | 323 | #define TESTPAGEFLAG(uname, lname, policy) \ |
d389a4a8 MWO |
324 | static __always_inline bool folio_test_##lname(struct folio *folio) \ |
325 | { return test_bit(PG_##lname, folio_flags(folio, FOLIO_##policy)); } \ | |
4b0f3261 | 326 | static __always_inline int Page##uname(struct page *page) \ |
d389a4a8 | 327 | { return test_bit(PG_##lname, &policy(page, 0)->flags); } |
f94a62e9 | 328 | |
95ad9755 | 329 | #define SETPAGEFLAG(uname, lname, policy) \ |
d389a4a8 MWO |
330 | static __always_inline \ |
331 | void folio_set_##lname(struct folio *folio) \ | |
332 | { set_bit(PG_##lname, folio_flags(folio, FOLIO_##policy)); } \ | |
4b0f3261 | 333 | static __always_inline void SetPage##uname(struct page *page) \ |
d389a4a8 | 334 | { set_bit(PG_##lname, &policy(page, 1)->flags); } |
f94a62e9 | 335 | |
95ad9755 | 336 | #define CLEARPAGEFLAG(uname, lname, policy) \ |
d389a4a8 MWO |
337 | static __always_inline \ |
338 | void folio_clear_##lname(struct folio *folio) \ | |
339 | { clear_bit(PG_##lname, folio_flags(folio, FOLIO_##policy)); } \ | |
4b0f3261 | 340 | static __always_inline void ClearPage##uname(struct page *page) \ |
d389a4a8 | 341 | { clear_bit(PG_##lname, &policy(page, 1)->flags); } |
f94a62e9 | 342 | |
95ad9755 | 343 | #define __SETPAGEFLAG(uname, lname, policy) \ |
d389a4a8 MWO |
344 | static __always_inline \ |
345 | void __folio_set_##lname(struct folio *folio) \ | |
346 | { __set_bit(PG_##lname, folio_flags(folio, FOLIO_##policy)); } \ | |
4b0f3261 | 347 | static __always_inline void __SetPage##uname(struct page *page) \ |
d389a4a8 | 348 | { __set_bit(PG_##lname, &policy(page, 1)->flags); } |
f94a62e9 | 349 | |
95ad9755 | 350 | #define __CLEARPAGEFLAG(uname, lname, policy) \ |
d389a4a8 MWO |
351 | static __always_inline \ |
352 | void __folio_clear_##lname(struct folio *folio) \ | |
353 | { __clear_bit(PG_##lname, folio_flags(folio, FOLIO_##policy)); } \ | |
4b0f3261 | 354 | static __always_inline void __ClearPage##uname(struct page *page) \ |
d389a4a8 | 355 | { __clear_bit(PG_##lname, &policy(page, 1)->flags); } |
f94a62e9 | 356 | |
95ad9755 | 357 | #define TESTSETFLAG(uname, lname, policy) \ |
d389a4a8 MWO |
358 | static __always_inline \ |
359 | bool folio_test_set_##lname(struct folio *folio) \ | |
360 | { return test_and_set_bit(PG_##lname, folio_flags(folio, FOLIO_##policy)); } \ | |
4b0f3261 | 361 | static __always_inline int TestSetPage##uname(struct page *page) \ |
d389a4a8 | 362 | { return test_and_set_bit(PG_##lname, &policy(page, 1)->flags); } |
f94a62e9 | 363 | |
95ad9755 | 364 | #define TESTCLEARFLAG(uname, lname, policy) \ |
d389a4a8 MWO |
365 | static __always_inline \ |
366 | bool folio_test_clear_##lname(struct folio *folio) \ | |
367 | { return test_and_clear_bit(PG_##lname, folio_flags(folio, FOLIO_##policy)); } \ | |
4b0f3261 | 368 | static __always_inline int TestClearPage##uname(struct page *page) \ |
d389a4a8 | 369 | { return test_and_clear_bit(PG_##lname, &policy(page, 1)->flags); } |
f94a62e9 | 370 | |
95ad9755 KS |
371 | #define PAGEFLAG(uname, lname, policy) \ |
372 | TESTPAGEFLAG(uname, lname, policy) \ | |
373 | SETPAGEFLAG(uname, lname, policy) \ | |
374 | CLEARPAGEFLAG(uname, lname, policy) | |
f94a62e9 | 375 | |
95ad9755 KS |
376 | #define __PAGEFLAG(uname, lname, policy) \ |
377 | TESTPAGEFLAG(uname, lname, policy) \ | |
378 | __SETPAGEFLAG(uname, lname, policy) \ | |
379 | __CLEARPAGEFLAG(uname, lname, policy) | |
f94a62e9 | 380 | |
95ad9755 KS |
381 | #define TESTSCFLAG(uname, lname, policy) \ |
382 | TESTSETFLAG(uname, lname, policy) \ | |
383 | TESTCLEARFLAG(uname, lname, policy) | |
f94a62e9 | 384 | |
d389a4a8 MWO |
385 | #define TESTPAGEFLAG_FALSE(uname, lname) \ |
386 | static inline bool folio_test_##lname(const struct folio *folio) { return 0; } \ | |
2f3e442c JW |
387 | static inline int Page##uname(const struct page *page) { return 0; } |
388 | ||
d389a4a8 MWO |
389 | #define SETPAGEFLAG_NOOP(uname, lname) \ |
390 | static inline void folio_set_##lname(struct folio *folio) { } \ | |
8a7a8544 LS |
391 | static inline void SetPage##uname(struct page *page) { } |
392 | ||
d389a4a8 MWO |
393 | #define CLEARPAGEFLAG_NOOP(uname, lname) \ |
394 | static inline void folio_clear_##lname(struct folio *folio) { } \ | |
8a7a8544 LS |
395 | static inline void ClearPage##uname(struct page *page) { } |
396 | ||
d389a4a8 MWO |
397 | #define __CLEARPAGEFLAG_NOOP(uname, lname) \ |
398 | static inline void __folio_clear_##lname(struct folio *folio) { } \ | |
8a7a8544 LS |
399 | static inline void __ClearPage##uname(struct page *page) { } |
400 | ||
d389a4a8 MWO |
401 | #define TESTSETFLAG_FALSE(uname, lname) \ |
402 | static inline bool folio_test_set_##lname(struct folio *folio) \ | |
403 | { return 0; } \ | |
2f3e442c JW |
404 | static inline int TestSetPage##uname(struct page *page) { return 0; } |
405 | ||
d389a4a8 MWO |
406 | #define TESTCLEARFLAG_FALSE(uname, lname) \ |
407 | static inline bool folio_test_clear_##lname(struct folio *folio) \ | |
408 | { return 0; } \ | |
8a7a8544 LS |
409 | static inline int TestClearPage##uname(struct page *page) { return 0; } |
410 | ||
d389a4a8 MWO |
411 | #define PAGEFLAG_FALSE(uname, lname) TESTPAGEFLAG_FALSE(uname, lname) \ |
412 | SETPAGEFLAG_NOOP(uname, lname) CLEARPAGEFLAG_NOOP(uname, lname) | |
2f3e442c | 413 | |
d389a4a8 MWO |
414 | #define TESTSCFLAG_FALSE(uname, lname) \ |
415 | TESTSETFLAG_FALSE(uname, lname) TESTCLEARFLAG_FALSE(uname, lname) | |
2f3e442c | 416 | |
48c935ad | 417 | __PAGEFLAG(Locked, locked, PF_NO_TAIL) |
62906027 | 418 | PAGEFLAG(Waiters, waiters, PF_ONLY_HEAD) __CLEARPAGEFLAG(Waiters, waiters, PF_ONLY_HEAD) |
d72520ad | 419 | PAGEFLAG(Error, error, PF_NO_TAIL) TESTCLEARFLAG(Error, error, PF_NO_TAIL) |
8cb38fab KS |
420 | PAGEFLAG(Referenced, referenced, PF_HEAD) |
421 | TESTCLEARFLAG(Referenced, referenced, PF_HEAD) | |
422 | __SETPAGEFLAG(Referenced, referenced, PF_HEAD) | |
df8c94d1 KS |
423 | PAGEFLAG(Dirty, dirty, PF_HEAD) TESTSCFLAG(Dirty, dirty, PF_HEAD) |
424 | __CLEARPAGEFLAG(Dirty, dirty, PF_HEAD) | |
8cb38fab | 425 | PAGEFLAG(LRU, lru, PF_HEAD) __CLEARPAGEFLAG(LRU, lru, PF_HEAD) |
d25b5bd8 | 426 | TESTCLEARFLAG(LRU, lru, PF_HEAD) |
8cb38fab KS |
427 | PAGEFLAG(Active, active, PF_HEAD) __CLEARPAGEFLAG(Active, active, PF_HEAD) |
428 | TESTCLEARFLAG(Active, active, PF_HEAD) | |
1899ad18 JW |
429 | PAGEFLAG(Workingset, workingset, PF_HEAD) |
430 | TESTCLEARFLAG(Workingset, workingset, PF_HEAD) | |
dcb351cd KS |
431 | __PAGEFLAG(Slab, slab, PF_NO_TAIL) |
432 | __PAGEFLAG(SlobFree, slob_free, PF_NO_TAIL) | |
df8c94d1 | 433 | PAGEFLAG(Checked, checked, PF_NO_COMPOUND) /* Used by some filesystems */ |
c13985fa KS |
434 | |
435 | /* Xen */ | |
436 | PAGEFLAG(Pinned, pinned, PF_NO_COMPOUND) | |
437 | TESTSCFLAG(Pinned, pinned, PF_NO_COMPOUND) | |
438 | PAGEFLAG(SavePinned, savepinned, PF_NO_COMPOUND); | |
439 | PAGEFLAG(Foreign, foreign, PF_NO_COMPOUND); | |
b877ac98 JG |
440 | PAGEFLAG(XenRemapped, xen_remapped, PF_NO_COMPOUND) |
441 | TESTCLEARFLAG(XenRemapped, xen_remapped, PF_NO_COMPOUND) | |
c13985fa | 442 | |
de09d31d KS |
443 | PAGEFLAG(Reserved, reserved, PF_NO_COMPOUND) |
444 | __CLEARPAGEFLAG(Reserved, reserved, PF_NO_COMPOUND) | |
d483da5b | 445 | __SETPAGEFLAG(Reserved, reserved, PF_NO_COMPOUND) |
da5efc40 KS |
446 | PAGEFLAG(SwapBacked, swapbacked, PF_NO_TAIL) |
447 | __CLEARPAGEFLAG(SwapBacked, swapbacked, PF_NO_TAIL) | |
448 | __SETPAGEFLAG(SwapBacked, swapbacked, PF_NO_TAIL) | |
95ad9755 | 449 | |
266cf658 DH |
450 | /* |
451 | * Private page markings that may be used by the filesystem that owns the page | |
452 | * for its own purposes. | |
453 | * - PG_private and PG_private_2 cause releasepage() and co to be invoked | |
454 | */ | |
2ee08717 | 455 | PAGEFLAG(Private, private, PF_ANY) |
95ad9755 KS |
456 | PAGEFLAG(Private2, private_2, PF_ANY) TESTSCFLAG(Private2, private_2, PF_ANY) |
457 | PAGEFLAG(OwnerPriv1, owner_priv_1, PF_ANY) | |
458 | TESTCLEARFLAG(OwnerPriv1, owner_priv_1, PF_ANY) | |
266cf658 | 459 | |
6a1e7f77 CL |
460 | /* |
461 | * Only test-and-set exist for PG_writeback. The unconditional operators are | |
462 | * risky: they bypass page accounting. | |
463 | */ | |
225311a4 HY |
464 | TESTPAGEFLAG(Writeback, writeback, PF_NO_TAIL) |
465 | TESTSCFLAG(Writeback, writeback, PF_NO_TAIL) | |
e2f0a0db | 466 | PAGEFLAG(MappedToDisk, mappedtodisk, PF_NO_TAIL) |
6a1e7f77 | 467 | |
579f8290 | 468 | /* PG_readahead is only used for reads; PG_reclaim is only for writes */ |
e2f0a0db KS |
469 | PAGEFLAG(Reclaim, reclaim, PF_NO_TAIL) |
470 | TESTCLEARFLAG(Reclaim, reclaim, PF_NO_TAIL) | |
d389a4a8 MWO |
471 | PAGEFLAG(Readahead, readahead, PF_NO_COMPOUND) |
472 | TESTCLEARFLAG(Readahead, readahead, PF_NO_COMPOUND) | |
6a1e7f77 CL |
473 | |
474 | #ifdef CONFIG_HIGHMEM | |
1da177e4 | 475 | /* |
6a1e7f77 CL |
476 | * Must use a macro here due to header dependency issues. page_zone() is not |
477 | * available at this point. | |
1da177e4 | 478 | */ |
3ca65c19 | 479 | #define PageHighMem(__p) is_highmem_idx(page_zonenum(__p)) |
6a1e7f77 | 480 | #else |
d389a4a8 | 481 | PAGEFLAG_FALSE(HighMem, highmem) |
6a1e7f77 CL |
482 | #endif |
483 | ||
484 | #ifdef CONFIG_SWAP | |
d389a4a8 | 485 | static __always_inline bool folio_test_swapcache(struct folio *folio) |
6326fec1 | 486 | { |
d389a4a8 MWO |
487 | return folio_test_swapbacked(folio) && |
488 | test_bit(PG_swapcache, folio_flags(folio, 0)); | |
489 | } | |
6326fec1 | 490 | |
d389a4a8 MWO |
491 | static __always_inline bool PageSwapCache(struct page *page) |
492 | { | |
493 | return folio_test_swapcache(page_folio(page)); | |
6326fec1 | 494 | } |
d389a4a8 | 495 | |
38d8b4e6 HY |
496 | SETPAGEFLAG(SwapCache, swapcache, PF_NO_TAIL) |
497 | CLEARPAGEFLAG(SwapCache, swapcache, PF_NO_TAIL) | |
6a1e7f77 | 498 | #else |
d389a4a8 | 499 | PAGEFLAG_FALSE(SwapCache, swapcache) |
6a1e7f77 CL |
500 | #endif |
501 | ||
8cb38fab KS |
502 | PAGEFLAG(Unevictable, unevictable, PF_HEAD) |
503 | __CLEARPAGEFLAG(Unevictable, unevictable, PF_HEAD) | |
504 | TESTCLEARFLAG(Unevictable, unevictable, PF_HEAD) | |
b291f000 | 505 | |
af8e3354 | 506 | #ifdef CONFIG_MMU |
e4f87d5d KS |
507 | PAGEFLAG(Mlocked, mlocked, PF_NO_TAIL) |
508 | __CLEARPAGEFLAG(Mlocked, mlocked, PF_NO_TAIL) | |
509 | TESTSCFLAG(Mlocked, mlocked, PF_NO_TAIL) | |
894bc310 | 510 | #else |
d389a4a8 MWO |
511 | PAGEFLAG_FALSE(Mlocked, mlocked) __CLEARPAGEFLAG_NOOP(Mlocked, mlocked) |
512 | TESTSCFLAG_FALSE(Mlocked, mlocked) | |
894bc310 LS |
513 | #endif |
514 | ||
46cf98cd | 515 | #ifdef CONFIG_ARCH_USES_PG_UNCACHED |
b9d41817 | 516 | PAGEFLAG(Uncached, uncached, PF_NO_COMPOUND) |
602c4d11 | 517 | #else |
d389a4a8 | 518 | PAGEFLAG_FALSE(Uncached, uncached) |
6a1e7f77 | 519 | #endif |
1da177e4 | 520 | |
d466f2fc | 521 | #ifdef CONFIG_MEMORY_FAILURE |
95ad9755 KS |
522 | PAGEFLAG(HWPoison, hwpoison, PF_ANY) |
523 | TESTSCFLAG(HWPoison, hwpoison, PF_ANY) | |
d466f2fc | 524 | #define __PG_HWPOISON (1UL << PG_hwpoison) |
06be6ff3 | 525 | extern bool take_page_off_buddy(struct page *page); |
d466f2fc | 526 | #else |
d389a4a8 | 527 | PAGEFLAG_FALSE(HWPoison, hwpoison) |
d466f2fc AK |
528 | #define __PG_HWPOISON 0 |
529 | #endif | |
530 | ||
1c676e0d | 531 | #if defined(CONFIG_PAGE_IDLE_FLAG) && defined(CONFIG_64BIT) |
95ad9755 KS |
532 | TESTPAGEFLAG(Young, young, PF_ANY) |
533 | SETPAGEFLAG(Young, young, PF_ANY) | |
534 | TESTCLEARFLAG(Young, young, PF_ANY) | |
535 | PAGEFLAG(Idle, idle, PF_ANY) | |
33c3fc71 VD |
536 | #endif |
537 | ||
c275c5c6 PC |
538 | #ifdef CONFIG_KASAN_HW_TAGS |
539 | PAGEFLAG(SkipKASanPoison, skip_kasan_poison, PF_HEAD) | |
540 | #else | |
d389a4a8 | 541 | PAGEFLAG_FALSE(SkipKASanPoison, skip_kasan_poison) |
c275c5c6 PC |
542 | #endif |
543 | ||
36e66c55 AD |
544 | /* |
545 | * PageReported() is used to track reported free pages within the Buddy | |
546 | * allocator. We can use the non-atomic version of the test and set | |
547 | * operations as both should be shielded with the zone lock to prevent | |
548 | * any possible races on the setting or clearing of the bit. | |
549 | */ | |
550 | __PAGEFLAG(Reported, reported, PF_NO_COMPOUND) | |
551 | ||
e8c6158f KS |
552 | /* |
553 | * On an anonymous page mapped into a user virtual memory area, | |
554 | * page->mapping points to its anon_vma, not to a struct address_space; | |
555 | * with the PAGE_MAPPING_ANON bit set to distinguish it. See rmap.h. | |
556 | * | |
557 | * On an anonymous page in a VM_MERGEABLE area, if CONFIG_KSM is enabled, | |
bda807d4 MK |
558 | * the PAGE_MAPPING_MOVABLE bit may be set along with the PAGE_MAPPING_ANON |
559 | * bit; and then page->mapping points, not to an anon_vma, but to a private | |
e8c6158f KS |
560 | * structure which KSM associates with that merged page. See ksm.h. |
561 | * | |
bda807d4 MK |
562 | * PAGE_MAPPING_KSM without PAGE_MAPPING_ANON is used for non-lru movable |
563 | * page and then page->mapping points a struct address_space. | |
e8c6158f KS |
564 | * |
565 | * Please note that, confusingly, "page_mapping" refers to the inode | |
566 | * address_space which maps the page from disk; whereas "page_mapped" | |
567 | * refers to user virtual address space into which the page is mapped. | |
568 | */ | |
bda807d4 MK |
569 | #define PAGE_MAPPING_ANON 0x1 |
570 | #define PAGE_MAPPING_MOVABLE 0x2 | |
571 | #define PAGE_MAPPING_KSM (PAGE_MAPPING_ANON | PAGE_MAPPING_MOVABLE) | |
572 | #define PAGE_MAPPING_FLAGS (PAGE_MAPPING_ANON | PAGE_MAPPING_MOVABLE) | |
e8c6158f | 573 | |
bda807d4 | 574 | static __always_inline int PageMappingFlags(struct page *page) |
17514574 | 575 | { |
bda807d4 | 576 | return ((unsigned long)page->mapping & PAGE_MAPPING_FLAGS) != 0; |
17514574 MG |
577 | } |
578 | ||
d389a4a8 | 579 | static __always_inline bool folio_test_anon(struct folio *folio) |
e8c6158f | 580 | { |
d389a4a8 MWO |
581 | return ((unsigned long)folio->mapping & PAGE_MAPPING_ANON) != 0; |
582 | } | |
583 | ||
584 | static __always_inline bool PageAnon(struct page *page) | |
e8c6158f | 585 | { |
d389a4a8 | 586 | return folio_test_anon(page_folio(page)); |
bda807d4 MK |
587 | } |
588 | ||
589 | static __always_inline int __PageMovable(struct page *page) | |
590 | { | |
591 | return ((unsigned long)page->mapping & PAGE_MAPPING_FLAGS) == | |
592 | PAGE_MAPPING_MOVABLE; | |
e8c6158f KS |
593 | } |
594 | ||
595 | #ifdef CONFIG_KSM | |
596 | /* | |
597 | * A KSM page is one of those write-protected "shared pages" or "merged pages" | |
598 | * which KSM maps into multiple mms, wherever identical anonymous page content | |
599 | * is found in VM_MERGEABLE vmas. It's a PageAnon page, pointing not to any | |
600 | * anon_vma, but to that page's node of the stable tree. | |
601 | */ | |
d389a4a8 | 602 | static __always_inline bool folio_test_ksm(struct folio *folio) |
e8c6158f | 603 | { |
d389a4a8 | 604 | return ((unsigned long)folio->mapping & PAGE_MAPPING_FLAGS) == |
bda807d4 | 605 | PAGE_MAPPING_KSM; |
e8c6158f | 606 | } |
d389a4a8 MWO |
607 | |
608 | static __always_inline bool PageKsm(struct page *page) | |
609 | { | |
610 | return folio_test_ksm(page_folio(page)); | |
611 | } | |
e8c6158f | 612 | #else |
d389a4a8 | 613 | TESTPAGEFLAG_FALSE(Ksm, ksm) |
e8c6158f KS |
614 | #endif |
615 | ||
1a9b5b7f WF |
616 | u64 stable_page_flags(struct page *page); |
617 | ||
d389a4a8 | 618 | static inline bool folio_test_uptodate(struct folio *folio) |
0ed361de | 619 | { |
d389a4a8 | 620 | bool ret = test_bit(PG_uptodate, folio_flags(folio, 0)); |
0ed361de | 621 | /* |
d389a4a8 MWO |
622 | * Must ensure that the data we read out of the folio is loaded |
623 | * _after_ we've loaded folio->flags to check the uptodate bit. | |
624 | * We can skip the barrier if the folio is not uptodate, because | |
0ed361de NP |
625 | * we wouldn't be reading anything from it. |
626 | * | |
d389a4a8 | 627 | * See folio_mark_uptodate() for the other side of the story. |
0ed361de NP |
628 | */ |
629 | if (ret) | |
630 | smp_rmb(); | |
631 | ||
632 | return ret; | |
633 | } | |
634 | ||
d389a4a8 MWO |
635 | static inline int PageUptodate(struct page *page) |
636 | { | |
637 | return folio_test_uptodate(page_folio(page)); | |
638 | } | |
639 | ||
640 | static __always_inline void __folio_mark_uptodate(struct folio *folio) | |
0ed361de NP |
641 | { |
642 | smp_wmb(); | |
d389a4a8 | 643 | __set_bit(PG_uptodate, folio_flags(folio, 0)); |
0ed361de NP |
644 | } |
645 | ||
d389a4a8 | 646 | static __always_inline void folio_mark_uptodate(struct folio *folio) |
2dcea57a | 647 | { |
0ed361de NP |
648 | /* |
649 | * Memory barrier must be issued before setting the PG_uptodate bit, | |
d389a4a8 MWO |
650 | * so that all previous stores issued in order to bring the folio |
651 | * uptodate are actually visible before folio_test_uptodate becomes true. | |
0ed361de NP |
652 | */ |
653 | smp_wmb(); | |
d389a4a8 MWO |
654 | set_bit(PG_uptodate, folio_flags(folio, 0)); |
655 | } | |
656 | ||
657 | static __always_inline void __SetPageUptodate(struct page *page) | |
658 | { | |
659 | __folio_mark_uptodate((struct folio *)page); | |
660 | } | |
661 | ||
662 | static __always_inline void SetPageUptodate(struct page *page) | |
663 | { | |
664 | folio_mark_uptodate((struct folio *)page); | |
0ed361de NP |
665 | } |
666 | ||
d2998c4d | 667 | CLEARPAGEFLAG(Uptodate, uptodate, PF_NO_TAIL) |
1da177e4 | 668 | |
f143f1ea MWO |
669 | bool __folio_start_writeback(struct folio *folio, bool keep_write); |
670 | bool set_page_writeback(struct page *page); | |
1c8349a1 | 671 | |
f143f1ea MWO |
672 | #define folio_start_writeback(folio) \ |
673 | __folio_start_writeback(folio, false) | |
674 | #define folio_start_writeback_keepwrite(folio) \ | |
675 | __folio_start_writeback(folio, true) | |
1da177e4 | 676 | |
f143f1ea | 677 | static inline void set_page_writeback_keepwrite(struct page *page) |
6a1e7f77 | 678 | { |
f143f1ea | 679 | folio_start_writeback_keepwrite(page_folio(page)); |
6a1e7f77 | 680 | } |
1da177e4 | 681 | |
f143f1ea | 682 | static inline bool test_set_page_writeback(struct page *page) |
1c8349a1 | 683 | { |
f143f1ea | 684 | return set_page_writeback(page); |
1c8349a1 NJ |
685 | } |
686 | ||
95ad9755 | 687 | __PAGEFLAG(Head, head, PF_ANY) CLEARPAGEFLAG(Head, head, PF_ANY) |
e20b8cca | 688 | |
d389a4a8 MWO |
689 | /* Whether there are one or multiple pages in a folio */ |
690 | static inline bool folio_test_single(struct folio *folio) | |
691 | { | |
692 | return !folio_test_head(folio); | |
693 | } | |
694 | ||
695 | static inline bool folio_test_multi(struct folio *folio) | |
696 | { | |
697 | return folio_test_head(folio); | |
698 | } | |
699 | ||
4b0f3261 | 700 | static __always_inline void set_compound_head(struct page *page, struct page *head) |
ad4b3fb7 | 701 | { |
1d798ca3 | 702 | WRITE_ONCE(page->compound_head, (unsigned long)head + 1); |
ad4b3fb7 CD |
703 | } |
704 | ||
4b0f3261 | 705 | static __always_inline void clear_compound_head(struct page *page) |
6a1e7f77 | 706 | { |
1d798ca3 | 707 | WRITE_ONCE(page->compound_head, 0); |
6a1e7f77 | 708 | } |
6d777953 | 709 | |
4e6af67e AA |
710 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
711 | static inline void ClearPageCompound(struct page *page) | |
712 | { | |
1d798ca3 KS |
713 | BUG_ON(!PageHead(page)); |
714 | ClearPageHead(page); | |
4e6af67e AA |
715 | } |
716 | #endif | |
717 | ||
d2a1a1f0 | 718 | #define PG_head_mask ((1UL << PG_head)) |
dfa7e20c | 719 | |
e8c6158f KS |
720 | #ifdef CONFIG_HUGETLB_PAGE |
721 | int PageHuge(struct page *page); | |
722 | int PageHeadHuge(struct page *page); | |
d389a4a8 MWO |
723 | static inline bool folio_test_hugetlb(struct folio *folio) |
724 | { | |
725 | return PageHeadHuge(&folio->page); | |
726 | } | |
e8c6158f | 727 | #else |
d389a4a8 MWO |
728 | TESTPAGEFLAG_FALSE(Huge, hugetlb) |
729 | TESTPAGEFLAG_FALSE(HeadHuge, headhuge) | |
e8c6158f KS |
730 | #endif |
731 | ||
936a5fe6 | 732 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
71e3aac0 AA |
733 | /* |
734 | * PageHuge() only returns true for hugetlbfs pages, but not for | |
735 | * normal or transparent huge pages. | |
736 | * | |
737 | * PageTransHuge() returns true for both transparent huge and | |
738 | * hugetlbfs pages, but not normal pages. PageTransHuge() can only be | |
739 | * called only in the core VM paths where hugetlbfs pages can't exist. | |
740 | */ | |
741 | static inline int PageTransHuge(struct page *page) | |
742 | { | |
309381fe | 743 | VM_BUG_ON_PAGE(PageTail(page), page); |
71e3aac0 AA |
744 | return PageHead(page); |
745 | } | |
746 | ||
d389a4a8 MWO |
747 | static inline bool folio_test_transhuge(struct folio *folio) |
748 | { | |
749 | return folio_test_head(folio); | |
750 | } | |
751 | ||
385de357 DN |
752 | /* |
753 | * PageTransCompound returns true for both transparent huge pages | |
754 | * and hugetlbfs pages, so it should only be called when it's known | |
755 | * that hugetlbfs pages aren't involved. | |
756 | */ | |
936a5fe6 AA |
757 | static inline int PageTransCompound(struct page *page) |
758 | { | |
759 | return PageCompound(page); | |
760 | } | |
71e3aac0 | 761 | |
385de357 DN |
762 | /* |
763 | * PageTransTail returns true for both transparent huge pages | |
764 | * and hugetlbfs pages, so it should only be called when it's known | |
765 | * that hugetlbfs pages aren't involved. | |
766 | */ | |
767 | static inline int PageTransTail(struct page *page) | |
768 | { | |
769 | return PageTail(page); | |
770 | } | |
771 | ||
53f9263b KS |
772 | /* |
773 | * PageDoubleMap indicates that the compound page is mapped with PTEs as well | |
774 | * as PMDs. | |
775 | * | |
776 | * This is required for optimization of rmap operations for THP: we can postpone | |
777 | * per small page mapcount accounting (and its overhead from atomic operations) | |
778 | * until the first PMD split. | |
779 | * | |
780 | * For the page PageDoubleMap means ->_mapcount in all sub-pages is offset up | |
781 | * by one. This reference will go away with last compound_mapcount. | |
782 | * | |
783 | * See also __split_huge_pmd_locked() and page_remove_anon_compound_rmap(). | |
784 | */ | |
a08d93e5 MWO |
785 | PAGEFLAG(DoubleMap, double_map, PF_SECOND) |
786 | TESTSCFLAG(DoubleMap, double_map, PF_SECOND) | |
936a5fe6 | 787 | #else |
d389a4a8 MWO |
788 | TESTPAGEFLAG_FALSE(TransHuge, transhuge) |
789 | TESTPAGEFLAG_FALSE(TransCompound, transcompound) | |
790 | TESTPAGEFLAG_FALSE(TransCompoundMap, transcompoundmap) | |
791 | TESTPAGEFLAG_FALSE(TransTail, transtail) | |
792 | PAGEFLAG_FALSE(DoubleMap, double_map) | |
793 | TESTSCFLAG_FALSE(DoubleMap, double_map) | |
936a5fe6 AA |
794 | #endif |
795 | ||
eac96c3e YS |
796 | #if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_TRANSPARENT_HUGEPAGE) |
797 | /* | |
798 | * PageHasHWPoisoned indicates that at least one subpage is hwpoisoned in the | |
799 | * compound page. | |
800 | * | |
801 | * This flag is set by hwpoison handler. Cleared by THP split or free page. | |
802 | */ | |
803 | PAGEFLAG(HasHWPoisoned, has_hwpoisoned, PF_SECOND) | |
804 | TESTSCFLAG(HasHWPoisoned, has_hwpoisoned, PF_SECOND) | |
805 | #else | |
806 | PAGEFLAG_FALSE(HasHWPoisoned) | |
807 | TESTSCFLAG_FALSE(HasHWPoisoned) | |
808 | #endif | |
809 | ||
0daa322b DH |
810 | /* |
811 | * Check if a page is currently marked HWPoisoned. Note that this check is | |
812 | * best effort only and inherently racy: there is no way to synchronize with | |
813 | * failing hardware. | |
814 | */ | |
815 | static inline bool is_page_hwpoison(struct page *page) | |
816 | { | |
817 | if (PageHWPoison(page)) | |
818 | return true; | |
819 | return PageHuge(page) && PageHWPoison(compound_head(page)); | |
820 | } | |
821 | ||
e8c6158f | 822 | /* |
6e292b9b MW |
823 | * For pages that are never mapped to userspace (and aren't PageSlab), |
824 | * page_type may be used. Because it is initialised to -1, we invert the | |
825 | * sense of the bit, so __SetPageFoo *clears* the bit used for PageFoo, and | |
826 | * __ClearPageFoo *sets* the bit used for PageFoo. We reserve a few high and | |
827 | * low bits so that an underflow or overflow of page_mapcount() won't be | |
828 | * mistaken for a page type value. | |
e8c6158f | 829 | */ |
6e292b9b MW |
830 | |
831 | #define PAGE_TYPE_BASE 0xf0000000 | |
832 | /* Reserve 0x0000007f to catch underflows of page_mapcount */ | |
144552ff | 833 | #define PAGE_MAPCOUNT_RESERVE -128 |
6e292b9b | 834 | #define PG_buddy 0x00000080 |
ca215086 | 835 | #define PG_offline 0x00000100 |
18b2db3b RG |
836 | #define PG_table 0x00000200 |
837 | #define PG_guard 0x00000400 | |
6e292b9b MW |
838 | |
839 | #define PageType(page, flag) \ | |
840 | ((page->page_type & (PAGE_TYPE_BASE | flag)) == PAGE_TYPE_BASE) | |
841 | ||
144552ff AY |
842 | static inline int page_has_type(struct page *page) |
843 | { | |
844 | return (int)page->page_type < PAGE_MAPCOUNT_RESERVE; | |
845 | } | |
846 | ||
6e292b9b | 847 | #define PAGE_TYPE_OPS(uname, lname) \ |
632c0a1a VD |
848 | static __always_inline int Page##uname(struct page *page) \ |
849 | { \ | |
6e292b9b | 850 | return PageType(page, PG_##lname); \ |
632c0a1a VD |
851 | } \ |
852 | static __always_inline void __SetPage##uname(struct page *page) \ | |
853 | { \ | |
6e292b9b MW |
854 | VM_BUG_ON_PAGE(!PageType(page, 0), page); \ |
855 | page->page_type &= ~PG_##lname; \ | |
632c0a1a VD |
856 | } \ |
857 | static __always_inline void __ClearPage##uname(struct page *page) \ | |
858 | { \ | |
859 | VM_BUG_ON_PAGE(!Page##uname(page), page); \ | |
6e292b9b | 860 | page->page_type |= PG_##lname; \ |
e8c6158f KS |
861 | } |
862 | ||
632c0a1a | 863 | /* |
6e292b9b | 864 | * PageBuddy() indicates that the page is free and in the buddy system |
632c0a1a VD |
865 | * (see mm/page_alloc.c). |
866 | */ | |
6e292b9b | 867 | PAGE_TYPE_OPS(Buddy, buddy) |
e8c6158f | 868 | |
632c0a1a | 869 | /* |
ca215086 DH |
870 | * PageOffline() indicates that the page is logically offline although the |
871 | * containing section is online. (e.g. inflated in a balloon driver or | |
872 | * not onlined when onlining the section). | |
873 | * The content of these pages is effectively stale. Such pages should not | |
874 | * be touched (read/write/dump/save) except by their owner. | |
aa218795 DH |
875 | * |
876 | * If a driver wants to allow to offline unmovable PageOffline() pages without | |
877 | * putting them back to the buddy, it can do so via the memory notifier by | |
878 | * decrementing the reference count in MEM_GOING_OFFLINE and incrementing the | |
879 | * reference count in MEM_CANCEL_OFFLINE. When offlining, the PageOffline() | |
880 | * pages (now with a reference count of zero) are treated like free pages, | |
881 | * allowing the containing memory block to get offlined. A driver that | |
882 | * relies on this feature is aware that re-onlining the memory block will | |
883 | * require to re-set the pages PageOffline() and not giving them to the | |
884 | * buddy via online_page_callback_t. | |
82840451 DH |
885 | * |
886 | * There are drivers that mark a page PageOffline() and expect there won't be | |
887 | * any further access to page content. PFN walkers that read content of random | |
888 | * pages should check PageOffline() and synchronize with such drivers using | |
889 | * page_offline_freeze()/page_offline_thaw(). | |
632c0a1a | 890 | */ |
ca215086 | 891 | PAGE_TYPE_OPS(Offline, offline) |
e8c6158f | 892 | |
82840451 DH |
893 | extern void page_offline_freeze(void); |
894 | extern void page_offline_thaw(void); | |
895 | extern void page_offline_begin(void); | |
896 | extern void page_offline_end(void); | |
897 | ||
1d40a5ea MW |
898 | /* |
899 | * Marks pages in use as page tables. | |
900 | */ | |
901 | PAGE_TYPE_OPS(Table, table) | |
902 | ||
3972f6bb VB |
903 | /* |
904 | * Marks guardpages used with debug_pagealloc. | |
905 | */ | |
906 | PAGE_TYPE_OPS(Guard, guard) | |
907 | ||
832fc1de NH |
908 | extern bool is_free_buddy_page(struct page *page); |
909 | ||
bda807d4 MK |
910 | __PAGEFLAG(Isolated, isolated, PF_ANY); |
911 | ||
072bb0aa MG |
912 | /* |
913 | * If network-based swap is enabled, sl*b must keep track of whether pages | |
914 | * were allocated from pfmemalloc reserves. | |
915 | */ | |
916 | static inline int PageSlabPfmemalloc(struct page *page) | |
917 | { | |
309381fe | 918 | VM_BUG_ON_PAGE(!PageSlab(page), page); |
072bb0aa MG |
919 | return PageActive(page); |
920 | } | |
921 | ||
0b303fb4 VB |
922 | /* |
923 | * A version of PageSlabPfmemalloc() for opportunistic checks where the page | |
924 | * might have been freed under us and not be a PageSlab anymore. | |
925 | */ | |
926 | static inline int __PageSlabPfmemalloc(struct page *page) | |
927 | { | |
928 | return PageActive(page); | |
929 | } | |
930 | ||
072bb0aa MG |
931 | static inline void SetPageSlabPfmemalloc(struct page *page) |
932 | { | |
309381fe | 933 | VM_BUG_ON_PAGE(!PageSlab(page), page); |
072bb0aa MG |
934 | SetPageActive(page); |
935 | } | |
936 | ||
937 | static inline void __ClearPageSlabPfmemalloc(struct page *page) | |
938 | { | |
309381fe | 939 | VM_BUG_ON_PAGE(!PageSlab(page), page); |
072bb0aa MG |
940 | __ClearPageActive(page); |
941 | } | |
942 | ||
943 | static inline void ClearPageSlabPfmemalloc(struct page *page) | |
944 | { | |
309381fe | 945 | VM_BUG_ON_PAGE(!PageSlab(page), page); |
072bb0aa MG |
946 | ClearPageActive(page); |
947 | } | |
948 | ||
af8e3354 | 949 | #ifdef CONFIG_MMU |
d2a1a1f0 | 950 | #define __PG_MLOCKED (1UL << PG_mlocked) |
33925b25 | 951 | #else |
b291f000 | 952 | #define __PG_MLOCKED 0 |
894bc310 LS |
953 | #endif |
954 | ||
dfa7e20c RA |
955 | /* |
956 | * Flags checked when a page is freed. Pages being freed should not have | |
4be408ce | 957 | * these flags set. If they are, there is a problem. |
dfa7e20c | 958 | */ |
6326fec1 NP |
959 | #define PAGE_FLAGS_CHECK_AT_FREE \ |
960 | (1UL << PG_lru | 1UL << PG_locked | \ | |
961 | 1UL << PG_private | 1UL << PG_private_2 | \ | |
962 | 1UL << PG_writeback | 1UL << PG_reserved | \ | |
963 | 1UL << PG_slab | 1UL << PG_active | \ | |
964 | 1UL << PG_unevictable | __PG_MLOCKED) | |
dfa7e20c RA |
965 | |
966 | /* | |
967 | * Flags checked when a page is prepped for return by the page allocator. | |
4be408ce | 968 | * Pages being prepped should not have these flags set. If they are set, |
79f4b7bf | 969 | * there has been a kernel bug or struct page corruption. |
f4c18e6f NH |
970 | * |
971 | * __PG_HWPOISON is exceptional because it needs to be kept beyond page's | |
972 | * alloc-free cycle to prevent from reusing the page. | |
dfa7e20c | 973 | */ |
f4c18e6f | 974 | #define PAGE_FLAGS_CHECK_AT_PREP \ |
41c961b9 | 975 | (PAGEFLAGS_MASK & ~__PG_HWPOISON) |
dfa7e20c | 976 | |
edcf4748 | 977 | #define PAGE_FLAGS_PRIVATE \ |
d2a1a1f0 | 978 | (1UL << PG_private | 1UL << PG_private_2) |
266cf658 DH |
979 | /** |
980 | * page_has_private - Determine if page has private stuff | |
981 | * @page: The page to be checked | |
982 | * | |
983 | * Determine if a page has private stuff, indicating that release routines | |
984 | * should be invoked upon it. | |
985 | */ | |
edcf4748 JW |
986 | static inline int page_has_private(struct page *page) |
987 | { | |
988 | return !!(page->flags & PAGE_FLAGS_PRIVATE); | |
989 | } | |
990 | ||
d389a4a8 MWO |
991 | static inline bool folio_has_private(struct folio *folio) |
992 | { | |
993 | return page_has_private(&folio->page); | |
994 | } | |
995 | ||
95ad9755 KS |
996 | #undef PF_ANY |
997 | #undef PF_HEAD | |
62906027 | 998 | #undef PF_ONLY_HEAD |
95ad9755 KS |
999 | #undef PF_NO_TAIL |
1000 | #undef PF_NO_COMPOUND | |
a08d93e5 | 1001 | #undef PF_SECOND |
edcf4748 | 1002 | #endif /* !__GENERATING_BOUNDS_H */ |
266cf658 | 1003 | |
1da177e4 | 1004 | #endif /* PAGE_FLAGS_H */ |