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b2441318 | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
1da177e4 LT |
2 | #ifndef _LINUX_PAGEMAP_H |
3 | #define _LINUX_PAGEMAP_H | |
4 | ||
5 | /* | |
6 | * Copyright 1995 Linus Torvalds | |
7 | */ | |
8 | #include <linux/mm.h> | |
9 | #include <linux/fs.h> | |
10 | #include <linux/list.h> | |
11 | #include <linux/highmem.h> | |
12 | #include <linux/compiler.h> | |
7c0f6ba6 | 13 | #include <linux/uaccess.h> |
1da177e4 | 14 | #include <linux/gfp.h> |
3e9f45bd | 15 | #include <linux/bitops.h> |
e286781d | 16 | #include <linux/hardirq.h> /* for in_interrupt() */ |
8edf344c | 17 | #include <linux/hugetlb_inline.h> |
1da177e4 | 18 | |
51dcbdac | 19 | struct folio_batch; |
aa65c29c | 20 | |
cbcc268b MWO |
21 | unsigned long invalidate_mapping_pages(struct address_space *mapping, |
22 | pgoff_t start, pgoff_t end); | |
23 | ||
24 | static inline void invalidate_remote_inode(struct inode *inode) | |
25 | { | |
26 | if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || | |
27 | S_ISLNK(inode->i_mode)) | |
28 | invalidate_mapping_pages(inode->i_mapping, 0, -1); | |
29 | } | |
30 | int invalidate_inode_pages2(struct address_space *mapping); | |
31 | int invalidate_inode_pages2_range(struct address_space *mapping, | |
32 | pgoff_t start, pgoff_t end); | |
e003f74a | 33 | int kiocb_invalidate_pages(struct kiocb *iocb, size_t count); |
c402a9a9 | 34 | void kiocb_invalidate_post_direct_write(struct kiocb *iocb, size_t count); |
3c435a0f | 35 | |
cbcc268b MWO |
36 | int write_inode_now(struct inode *, int sync); |
37 | int filemap_fdatawrite(struct address_space *); | |
38 | int filemap_flush(struct address_space *); | |
39 | int filemap_fdatawait_keep_errors(struct address_space *mapping); | |
40 | int filemap_fdatawait_range(struct address_space *, loff_t lstart, loff_t lend); | |
41 | int filemap_fdatawait_range_keep_errors(struct address_space *mapping, | |
42 | loff_t start_byte, loff_t end_byte); | |
74e797d7 DH |
43 | int filemap_invalidate_inode(struct inode *inode, bool flush, |
44 | loff_t start, loff_t end); | |
cbcc268b MWO |
45 | |
46 | static inline int filemap_fdatawait(struct address_space *mapping) | |
47 | { | |
48 | return filemap_fdatawait_range(mapping, 0, LLONG_MAX); | |
49 | } | |
50 | ||
51 | bool filemap_range_has_page(struct address_space *, loff_t lstart, loff_t lend); | |
52 | int filemap_write_and_wait_range(struct address_space *mapping, | |
53 | loff_t lstart, loff_t lend); | |
54 | int __filemap_fdatawrite_range(struct address_space *mapping, | |
55 | loff_t start, loff_t end, int sync_mode); | |
56 | int filemap_fdatawrite_range(struct address_space *mapping, | |
57 | loff_t start, loff_t end); | |
58 | int filemap_check_errors(struct address_space *mapping); | |
59 | void __filemap_set_wb_err(struct address_space *mapping, int err); | |
60 | int filemap_fdatawrite_wbc(struct address_space *mapping, | |
61 | struct writeback_control *wbc); | |
3c435a0f | 62 | int kiocb_write_and_wait(struct kiocb *iocb, size_t count); |
cbcc268b MWO |
63 | |
64 | static inline int filemap_write_and_wait(struct address_space *mapping) | |
65 | { | |
66 | return filemap_write_and_wait_range(mapping, 0, LLONG_MAX); | |
67 | } | |
68 | ||
69 | /** | |
70 | * filemap_set_wb_err - set a writeback error on an address_space | |
71 | * @mapping: mapping in which to set writeback error | |
72 | * @err: error to be set in mapping | |
73 | * | |
74 | * When writeback fails in some way, we must record that error so that | |
75 | * userspace can be informed when fsync and the like are called. We endeavor | |
76 | * to report errors on any file that was open at the time of the error. Some | |
77 | * internal callers also need to know when writeback errors have occurred. | |
78 | * | |
79 | * When a writeback error occurs, most filesystems will want to call | |
80 | * filemap_set_wb_err to record the error in the mapping so that it will be | |
81 | * automatically reported whenever fsync is called on the file. | |
82 | */ | |
83 | static inline void filemap_set_wb_err(struct address_space *mapping, int err) | |
84 | { | |
85 | /* Fastpath for common case of no error */ | |
86 | if (unlikely(err)) | |
87 | __filemap_set_wb_err(mapping, err); | |
88 | } | |
89 | ||
90 | /** | |
91 | * filemap_check_wb_err - has an error occurred since the mark was sampled? | |
92 | * @mapping: mapping to check for writeback errors | |
93 | * @since: previously-sampled errseq_t | |
94 | * | |
95 | * Grab the errseq_t value from the mapping, and see if it has changed "since" | |
96 | * the given value was sampled. | |
97 | * | |
98 | * If it has then report the latest error set, otherwise return 0. | |
99 | */ | |
100 | static inline int filemap_check_wb_err(struct address_space *mapping, | |
101 | errseq_t since) | |
102 | { | |
103 | return errseq_check(&mapping->wb_err, since); | |
104 | } | |
105 | ||
106 | /** | |
107 | * filemap_sample_wb_err - sample the current errseq_t to test for later errors | |
108 | * @mapping: mapping to be sampled | |
109 | * | |
110 | * Writeback errors are always reported relative to a particular sample point | |
111 | * in the past. This function provides those sample points. | |
112 | */ | |
113 | static inline errseq_t filemap_sample_wb_err(struct address_space *mapping) | |
114 | { | |
115 | return errseq_sample(&mapping->wb_err); | |
116 | } | |
117 | ||
118 | /** | |
119 | * file_sample_sb_err - sample the current errseq_t to test for later errors | |
120 | * @file: file pointer to be sampled | |
121 | * | |
122 | * Grab the most current superblock-level errseq_t value for the given | |
123 | * struct file. | |
124 | */ | |
125 | static inline errseq_t file_sample_sb_err(struct file *file) | |
126 | { | |
127 | return errseq_sample(&file->f_path.dentry->d_sb->s_wb_err); | |
128 | } | |
129 | ||
130 | /* | |
131 | * Flush file data before changing attributes. Caller must hold any locks | |
132 | * required to prevent further writes to this file until we're done setting | |
133 | * flags. | |
134 | */ | |
135 | static inline int inode_drain_writes(struct inode *inode) | |
136 | { | |
137 | inode_dio_wait(inode); | |
138 | return filemap_write_and_wait(inode->i_mapping); | |
139 | } | |
140 | ||
7716506a MWO |
141 | static inline bool mapping_empty(struct address_space *mapping) |
142 | { | |
143 | return xa_empty(&mapping->i_pages); | |
144 | } | |
145 | ||
51b8c1fe JW |
146 | /* |
147 | * mapping_shrinkable - test if page cache state allows inode reclaim | |
148 | * @mapping: the page cache mapping | |
149 | * | |
150 | * This checks the mapping's cache state for the pupose of inode | |
151 | * reclaim and LRU management. | |
152 | * | |
153 | * The caller is expected to hold the i_lock, but is not required to | |
154 | * hold the i_pages lock, which usually protects cache state. That's | |
155 | * because the i_lock and the list_lru lock that protect the inode and | |
156 | * its LRU state don't nest inside the irq-safe i_pages lock. | |
157 | * | |
158 | * Cache deletions are performed under the i_lock, which ensures that | |
159 | * when an inode goes empty, it will reliably get queued on the LRU. | |
160 | * | |
161 | * Cache additions do not acquire the i_lock and may race with this | |
162 | * check, in which case we'll report the inode as shrinkable when it | |
163 | * has cache pages. This is okay: the shrinker also checks the | |
164 | * refcount and the referenced bit, which will be elevated or set in | |
165 | * the process of adding new cache pages to an inode. | |
166 | */ | |
167 | static inline bool mapping_shrinkable(struct address_space *mapping) | |
168 | { | |
169 | void *head; | |
170 | ||
171 | /* | |
172 | * On highmem systems, there could be lowmem pressure from the | |
173 | * inodes before there is highmem pressure from the page | |
174 | * cache. Make inodes shrinkable regardless of cache state. | |
175 | */ | |
176 | if (IS_ENABLED(CONFIG_HIGHMEM)) | |
177 | return true; | |
178 | ||
179 | /* Cache completely empty? Shrink away. */ | |
180 | head = rcu_access_pointer(mapping->i_pages.xa_head); | |
181 | if (!head) | |
182 | return true; | |
183 | ||
184 | /* | |
185 | * The xarray stores single offset-0 entries directly in the | |
186 | * head pointer, which allows non-resident page cache entries | |
187 | * to escape the shadow shrinker's list of xarray nodes. The | |
188 | * inode shrinker needs to pick them up under memory pressure. | |
189 | */ | |
190 | if (!xa_is_node(head) && xa_is_value(head)) | |
191 | return true; | |
192 | ||
193 | return false; | |
194 | } | |
195 | ||
1da177e4 | 196 | /* |
9c5d760b | 197 | * Bits in mapping->flags. |
1da177e4 | 198 | */ |
9a896c9a | 199 | enum mapping_flags { |
9c5d760b MH |
200 | AS_EIO = 0, /* IO error on async write */ |
201 | AS_ENOSPC = 1, /* ENOSPC on async write */ | |
202 | AS_MM_ALL_LOCKS = 2, /* under mm_take_all_locks() */ | |
203 | AS_UNEVICTABLE = 3, /* e.g., ramdisk, SHM_LOCK */ | |
204 | AS_EXITING = 4, /* final truncate in progress */ | |
371a096e | 205 | /* writeback related tags are not used */ |
9c5d760b | 206 | AS_NO_WRITEBACK_TAGS = 5, |
ed2145c4 | 207 | AS_LARGE_FOLIO_SUPPORT = 6, |
b4fa966f | 208 | AS_RELEASE_ALWAYS, /* Call ->release_folio(), even if no private data */ |
762321da CH |
209 | AS_STABLE_WRITES, /* must wait for writeback before modifying |
210 | folio contents */ | |
13629252 | 211 | AS_UNMOVABLE, /* The mapping cannot be moved, ever */ |
9a896c9a | 212 | }; |
1da177e4 | 213 | |
8ed1e46a JL |
214 | /** |
215 | * mapping_set_error - record a writeback error in the address_space | |
767e5ee5 MWO |
216 | * @mapping: the mapping in which an error should be set |
217 | * @error: the error to set in the mapping | |
8ed1e46a JL |
218 | * |
219 | * When writeback fails in some way, we must record that error so that | |
220 | * userspace can be informed when fsync and the like are called. We endeavor | |
221 | * to report errors on any file that was open at the time of the error. Some | |
222 | * internal callers also need to know when writeback errors have occurred. | |
223 | * | |
224 | * When a writeback error occurs, most filesystems will want to call | |
225 | * mapping_set_error to record the error in the mapping so that it can be | |
226 | * reported when the application calls fsync(2). | |
227 | */ | |
3e9f45bd GC |
228 | static inline void mapping_set_error(struct address_space *mapping, int error) |
229 | { | |
8ed1e46a JL |
230 | if (likely(!error)) |
231 | return; | |
232 | ||
233 | /* Record in wb_err for checkers using errseq_t based tracking */ | |
735e4ae5 JL |
234 | __filemap_set_wb_err(mapping, error); |
235 | ||
236 | /* Record it in superblock */ | |
8b7b2eb1 MK |
237 | if (mapping->host) |
238 | errseq_set(&mapping->host->i_sb->s_wb_err, error); | |
8ed1e46a JL |
239 | |
240 | /* Record it in flags for now, for legacy callers */ | |
241 | if (error == -ENOSPC) | |
242 | set_bit(AS_ENOSPC, &mapping->flags); | |
243 | else | |
244 | set_bit(AS_EIO, &mapping->flags); | |
3e9f45bd GC |
245 | } |
246 | ||
ba9ddf49 LS |
247 | static inline void mapping_set_unevictable(struct address_space *mapping) |
248 | { | |
249 | set_bit(AS_UNEVICTABLE, &mapping->flags); | |
250 | } | |
251 | ||
89e004ea LS |
252 | static inline void mapping_clear_unevictable(struct address_space *mapping) |
253 | { | |
254 | clear_bit(AS_UNEVICTABLE, &mapping->flags); | |
255 | } | |
256 | ||
1eb6234e | 257 | static inline bool mapping_unevictable(struct address_space *mapping) |
ba9ddf49 | 258 | { |
1eb6234e | 259 | return mapping && test_bit(AS_UNEVICTABLE, &mapping->flags); |
ba9ddf49 | 260 | } |
ba9ddf49 | 261 | |
91b0abe3 JW |
262 | static inline void mapping_set_exiting(struct address_space *mapping) |
263 | { | |
264 | set_bit(AS_EXITING, &mapping->flags); | |
265 | } | |
266 | ||
267 | static inline int mapping_exiting(struct address_space *mapping) | |
268 | { | |
269 | return test_bit(AS_EXITING, &mapping->flags); | |
270 | } | |
271 | ||
371a096e HY |
272 | static inline void mapping_set_no_writeback_tags(struct address_space *mapping) |
273 | { | |
274 | set_bit(AS_NO_WRITEBACK_TAGS, &mapping->flags); | |
275 | } | |
276 | ||
277 | static inline int mapping_use_writeback_tags(struct address_space *mapping) | |
278 | { | |
279 | return !test_bit(AS_NO_WRITEBACK_TAGS, &mapping->flags); | |
280 | } | |
281 | ||
b4fa966f DH |
282 | static inline bool mapping_release_always(const struct address_space *mapping) |
283 | { | |
284 | return test_bit(AS_RELEASE_ALWAYS, &mapping->flags); | |
285 | } | |
286 | ||
287 | static inline void mapping_set_release_always(struct address_space *mapping) | |
288 | { | |
289 | set_bit(AS_RELEASE_ALWAYS, &mapping->flags); | |
290 | } | |
291 | ||
292 | static inline void mapping_clear_release_always(struct address_space *mapping) | |
293 | { | |
294 | clear_bit(AS_RELEASE_ALWAYS, &mapping->flags); | |
295 | } | |
296 | ||
762321da CH |
297 | static inline bool mapping_stable_writes(const struct address_space *mapping) |
298 | { | |
299 | return test_bit(AS_STABLE_WRITES, &mapping->flags); | |
300 | } | |
301 | ||
302 | static inline void mapping_set_stable_writes(struct address_space *mapping) | |
303 | { | |
304 | set_bit(AS_STABLE_WRITES, &mapping->flags); | |
305 | } | |
306 | ||
307 | static inline void mapping_clear_stable_writes(struct address_space *mapping) | |
308 | { | |
309 | clear_bit(AS_STABLE_WRITES, &mapping->flags); | |
310 | } | |
311 | ||
0003e2a4 SC |
312 | static inline void mapping_set_unmovable(struct address_space *mapping) |
313 | { | |
314 | /* | |
315 | * It's expected unmovable mappings are also unevictable. Compaction | |
316 | * migrate scanner (isolate_migratepages_block()) relies on this to | |
317 | * reduce page locking. | |
318 | */ | |
319 | set_bit(AS_UNEVICTABLE, &mapping->flags); | |
320 | set_bit(AS_UNMOVABLE, &mapping->flags); | |
321 | } | |
322 | ||
323 | static inline bool mapping_unmovable(struct address_space *mapping) | |
324 | { | |
325 | return test_bit(AS_UNMOVABLE, &mapping->flags); | |
326 | } | |
327 | ||
dd0fc66f | 328 | static inline gfp_t mapping_gfp_mask(struct address_space * mapping) |
1da177e4 | 329 | { |
9c5d760b | 330 | return mapping->gfp_mask; |
1da177e4 LT |
331 | } |
332 | ||
c62d2555 MH |
333 | /* Restricts the given gfp_mask to what the mapping allows. */ |
334 | static inline gfp_t mapping_gfp_constraint(struct address_space *mapping, | |
335 | gfp_t gfp_mask) | |
336 | { | |
337 | return mapping_gfp_mask(mapping) & gfp_mask; | |
338 | } | |
339 | ||
1da177e4 LT |
340 | /* |
341 | * This is non-atomic. Only to be used before the mapping is activated. | |
342 | * Probably needs a barrier... | |
343 | */ | |
260b2367 | 344 | static inline void mapping_set_gfp_mask(struct address_space *m, gfp_t mask) |
1da177e4 | 345 | { |
9c5d760b | 346 | m->gfp_mask = mask; |
1da177e4 LT |
347 | } |
348 | ||
79c13745 XY |
349 | /* |
350 | * There are some parts of the kernel which assume that PMD entries | |
351 | * are exactly HPAGE_PMD_ORDER. Those should be fixed, but until then, | |
352 | * limit the maximum allocation order to PMD size. I'm not aware of any | |
353 | * assumptions about maximum order if THP are disabled, but 8 seems like | |
354 | * a good order (that's 1MB if you're using 4kB pages) | |
355 | */ | |
356 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE | |
357 | #define MAX_PAGECACHE_ORDER HPAGE_PMD_ORDER | |
358 | #else | |
359 | #define MAX_PAGECACHE_ORDER 8 | |
360 | #endif | |
361 | ||
ff36da69 MWO |
362 | /** |
363 | * mapping_set_large_folios() - Indicate the file supports large folios. | |
364 | * @mapping: The file. | |
365 | * | |
366 | * The filesystem should call this function in its inode constructor to | |
367 | * indicate that the VFS can use large folios to cache the contents of | |
368 | * the file. | |
369 | * | |
370 | * Context: This should not be called while the inode is active as it | |
371 | * is non-atomic. | |
372 | */ | |
373 | static inline void mapping_set_large_folios(struct address_space *mapping) | |
374 | { | |
ed2145c4 | 375 | __set_bit(AS_LARGE_FOLIO_SUPPORT, &mapping->flags); |
ff36da69 MWO |
376 | } |
377 | ||
421f1ab4 MWO |
378 | /* |
379 | * Large folio support currently depends on THP. These dependencies are | |
380 | * being worked on but are not yet fixed. | |
381 | */ | |
ed2145c4 | 382 | static inline bool mapping_large_folio_support(struct address_space *mapping) |
01c70267 | 383 | { |
421f1ab4 MWO |
384 | return IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && |
385 | test_bit(AS_LARGE_FOLIO_SUPPORT, &mapping->flags); | |
01c70267 MWO |
386 | } |
387 | ||
79c13745 XY |
388 | /* Return the maximum folio size for this pagecache mapping, in bytes. */ |
389 | static inline size_t mapping_max_folio_size(struct address_space *mapping) | |
390 | { | |
391 | if (mapping_large_folio_support(mapping)) | |
392 | return PAGE_SIZE << MAX_PAGECACHE_ORDER; | |
393 | return PAGE_SIZE; | |
394 | } | |
395 | ||
6f4d2f97 MWO |
396 | static inline int filemap_nr_thps(struct address_space *mapping) |
397 | { | |
398 | #ifdef CONFIG_READ_ONLY_THP_FOR_FS | |
399 | return atomic_read(&mapping->nr_thps); | |
400 | #else | |
401 | return 0; | |
402 | #endif | |
403 | } | |
404 | ||
405 | static inline void filemap_nr_thps_inc(struct address_space *mapping) | |
406 | { | |
407 | #ifdef CONFIG_READ_ONLY_THP_FOR_FS | |
ed2145c4 | 408 | if (!mapping_large_folio_support(mapping)) |
6f4d2f97 MWO |
409 | atomic_inc(&mapping->nr_thps); |
410 | #else | |
06d44142 | 411 | WARN_ON_ONCE(mapping_large_folio_support(mapping) == 0); |
6f4d2f97 MWO |
412 | #endif |
413 | } | |
414 | ||
415 | static inline void filemap_nr_thps_dec(struct address_space *mapping) | |
416 | { | |
417 | #ifdef CONFIG_READ_ONLY_THP_FOR_FS | |
ed2145c4 | 418 | if (!mapping_large_folio_support(mapping)) |
6f4d2f97 MWO |
419 | atomic_dec(&mapping->nr_thps); |
420 | #else | |
06d44142 | 421 | WARN_ON_ONCE(mapping_large_folio_support(mapping) == 0); |
6f4d2f97 MWO |
422 | #endif |
423 | } | |
424 | ||
2f52578f MWO |
425 | struct address_space *page_mapping(struct page *); |
426 | struct address_space *folio_mapping(struct folio *); | |
427 | struct address_space *swapcache_mapping(struct folio *); | |
428 | ||
429 | /** | |
430 | * folio_file_mapping - Find the mapping this folio belongs to. | |
431 | * @folio: The folio. | |
432 | * | |
433 | * For folios which are in the page cache, return the mapping that this | |
434 | * page belongs to. Folios in the swap cache return the mapping of the | |
435 | * swap file or swap device where the data is stored. This is different | |
436 | * from the mapping returned by folio_mapping(). The only reason to | |
437 | * use it is if, like NFS, you return 0 from ->activate_swapfile. | |
438 | * | |
439 | * Do not call this for folios which aren't in the page cache or swap cache. | |
440 | */ | |
441 | static inline struct address_space *folio_file_mapping(struct folio *folio) | |
442 | { | |
443 | if (unlikely(folio_test_swapcache(folio))) | |
444 | return swapcache_mapping(folio); | |
445 | ||
446 | return folio->mapping; | |
447 | } | |
448 | ||
bc60abfb MWO |
449 | /** |
450 | * folio_flush_mapping - Find the file mapping this folio belongs to. | |
451 | * @folio: The folio. | |
452 | * | |
453 | * For folios which are in the page cache, return the mapping that this | |
454 | * page belongs to. Anonymous folios return NULL, even if they're in | |
455 | * the swap cache. Other kinds of folio also return NULL. | |
456 | * | |
457 | * This is ONLY used by architecture cache flushing code. If you aren't | |
458 | * writing cache flushing code, you want either folio_mapping() or | |
459 | * folio_file_mapping(). | |
842ca547 | 460 | */ |
bc60abfb | 461 | static inline struct address_space *folio_flush_mapping(struct folio *folio) |
842ca547 | 462 | { |
2f52578f | 463 | if (unlikely(folio_test_swapcache(folio))) |
842ca547 | 464 | return NULL; |
bc60abfb | 465 | |
2f52578f | 466 | return folio_mapping(folio); |
842ca547 MWO |
467 | } |
468 | ||
2f52578f MWO |
469 | static inline struct address_space *page_file_mapping(struct page *page) |
470 | { | |
471 | return folio_file_mapping(page_folio(page)); | |
842ca547 MWO |
472 | } |
473 | ||
452c472e DH |
474 | /** |
475 | * folio_inode - Get the host inode for this folio. | |
476 | * @folio: The folio. | |
477 | * | |
478 | * For folios which are in the page cache, return the inode that this folio | |
479 | * belongs to. | |
480 | * | |
481 | * Do not call this for folios which aren't in the page cache. | |
482 | */ | |
483 | static inline struct inode *folio_inode(struct folio *folio) | |
484 | { | |
485 | return folio->mapping->host; | |
486 | } | |
487 | ||
b03143ac | 488 | /** |
85d0a2ed MWO |
489 | * folio_attach_private - Attach private data to a folio. |
490 | * @folio: Folio to attach data to. | |
491 | * @data: Data to attach to folio. | |
b03143ac | 492 | * |
85d0a2ed MWO |
493 | * Attaching private data to a folio increments the page's reference count. |
494 | * The data must be detached before the folio will be freed. | |
b03143ac | 495 | */ |
85d0a2ed | 496 | static inline void folio_attach_private(struct folio *folio, void *data) |
b03143ac | 497 | { |
85d0a2ed MWO |
498 | folio_get(folio); |
499 | folio->private = data; | |
500 | folio_set_private(folio); | |
b03143ac GJ |
501 | } |
502 | ||
a19672f6 DH |
503 | /** |
504 | * folio_change_private - Change private data on a folio. | |
505 | * @folio: Folio to change the data on. | |
506 | * @data: Data to set on the folio. | |
507 | * | |
508 | * Change the private data attached to a folio and return the old | |
509 | * data. The page must previously have had data attached and the data | |
510 | * must be detached before the folio will be freed. | |
511 | * | |
512 | * Return: Data that was previously attached to the folio. | |
513 | */ | |
514 | static inline void *folio_change_private(struct folio *folio, void *data) | |
515 | { | |
516 | void *old = folio_get_private(folio); | |
517 | ||
518 | folio->private = data; | |
519 | return old; | |
520 | } | |
521 | ||
b03143ac | 522 | /** |
85d0a2ed MWO |
523 | * folio_detach_private - Detach private data from a folio. |
524 | * @folio: Folio to detach data from. | |
b03143ac | 525 | * |
85d0a2ed | 526 | * Removes the data that was previously attached to the folio and decrements |
b03143ac GJ |
527 | * the refcount on the page. |
528 | * | |
85d0a2ed | 529 | * Return: Data that was attached to the folio. |
b03143ac | 530 | */ |
85d0a2ed | 531 | static inline void *folio_detach_private(struct folio *folio) |
b03143ac | 532 | { |
85d0a2ed | 533 | void *data = folio_get_private(folio); |
b03143ac | 534 | |
85d0a2ed | 535 | if (!folio_test_private(folio)) |
b03143ac | 536 | return NULL; |
85d0a2ed MWO |
537 | folio_clear_private(folio); |
538 | folio->private = NULL; | |
539 | folio_put(folio); | |
b03143ac GJ |
540 | |
541 | return data; | |
542 | } | |
543 | ||
85d0a2ed MWO |
544 | static inline void attach_page_private(struct page *page, void *data) |
545 | { | |
546 | folio_attach_private(page_folio(page), data); | |
547 | } | |
548 | ||
549 | static inline void *detach_page_private(struct page *page) | |
550 | { | |
551 | return folio_detach_private(page_folio(page)); | |
552 | } | |
553 | ||
44110fe3 | 554 | #ifdef CONFIG_NUMA |
b951aaff | 555 | struct folio *filemap_alloc_folio_noprof(gfp_t gfp, unsigned int order); |
44110fe3 | 556 | #else |
b951aaff | 557 | static inline struct folio *filemap_alloc_folio_noprof(gfp_t gfp, unsigned int order) |
2ae88149 | 558 | { |
b951aaff | 559 | return folio_alloc_noprof(gfp, order); |
2ae88149 NP |
560 | } |
561 | #endif | |
562 | ||
b951aaff SB |
563 | #define filemap_alloc_folio(...) \ |
564 | alloc_hooks(filemap_alloc_folio_noprof(__VA_ARGS__)) | |
565 | ||
bb3c579e MWO |
566 | static inline struct page *__page_cache_alloc(gfp_t gfp) |
567 | { | |
568 | return &filemap_alloc_folio(gfp, 0)->page; | |
569 | } | |
570 | ||
8a5c743e | 571 | static inline gfp_t readahead_gfp_mask(struct address_space *x) |
7b1de586 | 572 | { |
453f85d4 | 573 | return mapping_gfp_mask(x) | __GFP_NORETRY | __GFP_NOWARN; |
7b1de586 WF |
574 | } |
575 | ||
e9b5b23e | 576 | typedef int filler_t(struct file *, struct folio *); |
1da177e4 | 577 | |
0d3f9296 | 578 | pgoff_t page_cache_next_miss(struct address_space *mapping, |
e7b563bb | 579 | pgoff_t index, unsigned long max_scan); |
0d3f9296 | 580 | pgoff_t page_cache_prev_miss(struct address_space *mapping, |
e7b563bb JW |
581 | pgoff_t index, unsigned long max_scan); |
582 | ||
ffc143db MWO |
583 | /** |
584 | * typedef fgf_t - Flags for getting folios from the page cache. | |
585 | * | |
586 | * Most users of the page cache will not need to use these flags; | |
587 | * there are convenience functions such as filemap_get_folio() and | |
588 | * filemap_lock_folio(). For users which need more control over exactly | |
589 | * what is done with the folios, these flags to __filemap_get_folio() | |
590 | * are available. | |
591 | * | |
592 | * * %FGP_ACCESSED - The folio will be marked accessed. | |
593 | * * %FGP_LOCK - The folio is returned locked. | |
594 | * * %FGP_CREAT - If no folio is present then a new folio is allocated, | |
595 | * added to the page cache and the VM's LRU list. The folio is | |
596 | * returned locked. | |
597 | * * %FGP_FOR_MMAP - The caller wants to do its own locking dance if the | |
598 | * folio is already in cache. If the folio was allocated, unlock it | |
599 | * before returning so the caller can do the same dance. | |
600 | * * %FGP_WRITE - The folio will be written to by the caller. | |
601 | * * %FGP_NOFS - __GFP_FS will get cleared in gfp. | |
602 | * * %FGP_NOWAIT - Don't block on the folio lock. | |
603 | * * %FGP_STABLE - Wait for the folio to be stable (finished writeback) | |
604 | * * %FGP_WRITEBEGIN - The flags to use in a filesystem write_begin() | |
605 | * implementation. | |
606 | */ | |
607 | typedef unsigned int __bitwise fgf_t; | |
608 | ||
609 | #define FGP_ACCESSED ((__force fgf_t)0x00000001) | |
610 | #define FGP_LOCK ((__force fgf_t)0x00000002) | |
611 | #define FGP_CREAT ((__force fgf_t)0x00000004) | |
612 | #define FGP_WRITE ((__force fgf_t)0x00000008) | |
613 | #define FGP_NOFS ((__force fgf_t)0x00000010) | |
614 | #define FGP_NOWAIT ((__force fgf_t)0x00000020) | |
615 | #define FGP_FOR_MMAP ((__force fgf_t)0x00000040) | |
616 | #define FGP_STABLE ((__force fgf_t)0x00000080) | |
4f661701 | 617 | #define FGF_GET_ORDER(fgf) (((__force unsigned)fgf) >> 26) /* top 6 bits */ |
2457aec6 | 618 | |
e999a5c5 MW |
619 | #define FGP_WRITEBEGIN (FGP_LOCK | FGP_WRITE | FGP_CREAT | FGP_STABLE) |
620 | ||
4f661701 MWO |
621 | /** |
622 | * fgf_set_order - Encode a length in the fgf_t flags. | |
623 | * @size: The suggested size of the folio to create. | |
624 | * | |
625 | * The caller of __filemap_get_folio() can use this to suggest a preferred | |
626 | * size for the folio that is created. If there is already a folio at | |
627 | * the index, it will be returned, no matter what its size. If a folio | |
628 | * is freshly created, it may be of a different size than requested | |
629 | * due to alignment constraints, memory pressure, or the presence of | |
630 | * other folios at nearby indices. | |
631 | */ | |
632 | static inline fgf_t fgf_set_order(size_t size) | |
633 | { | |
634 | unsigned int shift = ilog2(size); | |
635 | ||
636 | if (shift <= PAGE_SHIFT) | |
637 | return 0; | |
638 | return (__force fgf_t)((shift - PAGE_SHIFT) << 26); | |
639 | } | |
640 | ||
263e721e | 641 | void *filemap_get_entry(struct address_space *mapping, pgoff_t index); |
3f0c6a07 | 642 | struct folio *__filemap_get_folio(struct address_space *mapping, pgoff_t index, |
ffc143db | 643 | fgf_t fgp_flags, gfp_t gfp); |
3f0c6a07 | 644 | struct page *pagecache_get_page(struct address_space *mapping, pgoff_t index, |
ffc143db | 645 | fgf_t fgp_flags, gfp_t gfp); |
3f0c6a07 MWO |
646 | |
647 | /** | |
648 | * filemap_get_folio - Find and get a folio. | |
649 | * @mapping: The address_space to search. | |
650 | * @index: The page index. | |
651 | * | |
652 | * Looks up the page cache entry at @mapping & @index. If a folio is | |
653 | * present, it is returned with an increased refcount. | |
654 | * | |
66dabbb6 CH |
655 | * Return: A folio or ERR_PTR(-ENOENT) if there is no folio in the cache for |
656 | * this index. Will not return a shadow, swap or DAX entry. | |
3f0c6a07 MWO |
657 | */ |
658 | static inline struct folio *filemap_get_folio(struct address_space *mapping, | |
659 | pgoff_t index) | |
660 | { | |
661 | return __filemap_get_folio(mapping, index, 0, 0); | |
662 | } | |
2457aec6 | 663 | |
ccd16945 MWO |
664 | /** |
665 | * filemap_lock_folio - Find and lock a folio. | |
666 | * @mapping: The address_space to search. | |
667 | * @index: The page index. | |
668 | * | |
669 | * Looks up the page cache entry at @mapping & @index. If a folio is | |
670 | * present, it is returned locked with an increased refcount. | |
671 | * | |
672 | * Context: May sleep. | |
66dabbb6 CH |
673 | * Return: A folio or ERR_PTR(-ENOENT) if there is no folio in the cache for |
674 | * this index. Will not return a shadow, swap or DAX entry. | |
ccd16945 MWO |
675 | */ |
676 | static inline struct folio *filemap_lock_folio(struct address_space *mapping, | |
677 | pgoff_t index) | |
678 | { | |
679 | return __filemap_get_folio(mapping, index, FGP_LOCK, 0); | |
680 | } | |
681 | ||
ee7a5906 VMO |
682 | /** |
683 | * filemap_grab_folio - grab a folio from the page cache | |
684 | * @mapping: The address space to search | |
685 | * @index: The page index | |
686 | * | |
687 | * Looks up the page cache entry at @mapping & @index. If no folio is found, | |
688 | * a new folio is created. The folio is locked, marked as accessed, and | |
689 | * returned. | |
690 | * | |
66dabbb6 CH |
691 | * Return: A found or created folio. ERR_PTR(-ENOMEM) if no folio is found |
692 | * and failed to create a folio. | |
ee7a5906 VMO |
693 | */ |
694 | static inline struct folio *filemap_grab_folio(struct address_space *mapping, | |
695 | pgoff_t index) | |
696 | { | |
697 | return __filemap_get_folio(mapping, index, | |
698 | FGP_LOCK | FGP_ACCESSED | FGP_CREAT, | |
699 | mapping_gfp_mask(mapping)); | |
700 | } | |
701 | ||
2457aec6 MG |
702 | /** |
703 | * find_get_page - find and get a page reference | |
704 | * @mapping: the address_space to search | |
705 | * @offset: the page index | |
706 | * | |
707 | * Looks up the page cache slot at @mapping & @offset. If there is a | |
708 | * page cache page, it is returned with an increased refcount. | |
709 | * | |
710 | * Otherwise, %NULL is returned. | |
711 | */ | |
712 | static inline struct page *find_get_page(struct address_space *mapping, | |
713 | pgoff_t offset) | |
714 | { | |
45f87de5 | 715 | return pagecache_get_page(mapping, offset, 0, 0); |
2457aec6 MG |
716 | } |
717 | ||
718 | static inline struct page *find_get_page_flags(struct address_space *mapping, | |
ffc143db | 719 | pgoff_t offset, fgf_t fgp_flags) |
2457aec6 | 720 | { |
45f87de5 | 721 | return pagecache_get_page(mapping, offset, fgp_flags, 0); |
2457aec6 MG |
722 | } |
723 | ||
724 | /** | |
725 | * find_lock_page - locate, pin and lock a pagecache page | |
2457aec6 | 726 | * @mapping: the address_space to search |
89b42235 | 727 | * @index: the page index |
2457aec6 | 728 | * |
89b42235 | 729 | * Looks up the page cache entry at @mapping & @index. If there is a |
2457aec6 MG |
730 | * page cache page, it is returned locked and with an increased |
731 | * refcount. | |
732 | * | |
a8cf7f27 MWO |
733 | * Context: May sleep. |
734 | * Return: A struct page or %NULL if there is no page in the cache for this | |
735 | * index. | |
2457aec6 MG |
736 | */ |
737 | static inline struct page *find_lock_page(struct address_space *mapping, | |
a8cf7f27 MWO |
738 | pgoff_t index) |
739 | { | |
740 | return pagecache_get_page(mapping, index, FGP_LOCK, 0); | |
741 | } | |
742 | ||
2457aec6 MG |
743 | /** |
744 | * find_or_create_page - locate or add a pagecache page | |
745 | * @mapping: the page's address_space | |
746 | * @index: the page's index into the mapping | |
747 | * @gfp_mask: page allocation mode | |
748 | * | |
749 | * Looks up the page cache slot at @mapping & @offset. If there is a | |
750 | * page cache page, it is returned locked and with an increased | |
751 | * refcount. | |
752 | * | |
753 | * If the page is not present, a new page is allocated using @gfp_mask | |
754 | * and added to the page cache and the VM's LRU list. The page is | |
755 | * returned locked and with an increased refcount. | |
756 | * | |
757 | * On memory exhaustion, %NULL is returned. | |
758 | * | |
759 | * find_or_create_page() may sleep, even if @gfp_flags specifies an | |
760 | * atomic allocation! | |
761 | */ | |
762 | static inline struct page *find_or_create_page(struct address_space *mapping, | |
767e5ee5 | 763 | pgoff_t index, gfp_t gfp_mask) |
2457aec6 | 764 | { |
767e5ee5 | 765 | return pagecache_get_page(mapping, index, |
2457aec6 | 766 | FGP_LOCK|FGP_ACCESSED|FGP_CREAT, |
45f87de5 | 767 | gfp_mask); |
2457aec6 MG |
768 | } |
769 | ||
770 | /** | |
771 | * grab_cache_page_nowait - returns locked page at given index in given cache | |
772 | * @mapping: target address_space | |
773 | * @index: the page index | |
774 | * | |
775 | * Same as grab_cache_page(), but do not wait if the page is unavailable. | |
776 | * This is intended for speculative data generators, where the data can | |
777 | * be regenerated if the page couldn't be grabbed. This routine should | |
778 | * be safe to call while holding the lock for another page. | |
779 | * | |
780 | * Clear __GFP_FS when allocating the page to avoid recursion into the fs | |
781 | * and deadlock against the caller's locked page. | |
782 | */ | |
783 | static inline struct page *grab_cache_page_nowait(struct address_space *mapping, | |
784 | pgoff_t index) | |
785 | { | |
786 | return pagecache_get_page(mapping, index, | |
787 | FGP_LOCK|FGP_CREAT|FGP_NOFS|FGP_NOWAIT, | |
45f87de5 | 788 | mapping_gfp_mask(mapping)); |
2457aec6 MG |
789 | } |
790 | ||
9257e156 MWO |
791 | #define swapcache_index(folio) __page_file_index(&(folio)->page) |
792 | ||
793 | /** | |
794 | * folio_index - File index of a folio. | |
795 | * @folio: The folio. | |
796 | * | |
797 | * For a folio which is either in the page cache or the swap cache, | |
798 | * return its index within the address_space it belongs to. If you know | |
799 | * the page is definitely in the page cache, you can look at the folio's | |
800 | * index directly. | |
801 | * | |
802 | * Return: The index (offset in units of pages) of a folio in its file. | |
803 | */ | |
804 | static inline pgoff_t folio_index(struct folio *folio) | |
805 | { | |
806 | if (unlikely(folio_test_swapcache(folio))) | |
807 | return swapcache_index(folio); | |
808 | return folio->index; | |
809 | } | |
810 | ||
f94b18f6 MWO |
811 | /** |
812 | * folio_next_index - Get the index of the next folio. | |
813 | * @folio: The current folio. | |
814 | * | |
815 | * Return: The index of the folio which follows this folio in the file. | |
816 | */ | |
817 | static inline pgoff_t folio_next_index(struct folio *folio) | |
818 | { | |
819 | return folio->index + folio_nr_pages(folio); | |
820 | } | |
821 | ||
9257e156 MWO |
822 | /** |
823 | * folio_file_page - The page for a particular index. | |
824 | * @folio: The folio which contains this index. | |
825 | * @index: The index we want to look up. | |
826 | * | |
827 | * Sometimes after looking up a folio in the page cache, we need to | |
828 | * obtain the specific page for an index (eg a page fault). | |
829 | * | |
830 | * Return: The page containing the file data for this index. | |
831 | */ | |
832 | static inline struct page *folio_file_page(struct folio *folio, pgoff_t index) | |
833 | { | |
9257e156 MWO |
834 | return folio_page(folio, index & (folio_nr_pages(folio) - 1)); |
835 | } | |
836 | ||
837 | /** | |
838 | * folio_contains - Does this folio contain this index? | |
839 | * @folio: The folio. | |
840 | * @index: The page index within the file. | |
841 | * | |
842 | * Context: The caller should have the page locked in order to prevent | |
843 | * (eg) shmem from moving the page between the page cache and swap cache | |
844 | * and changing its index in the middle of the operation. | |
845 | * Return: true or false. | |
846 | */ | |
847 | static inline bool folio_contains(struct folio *folio, pgoff_t index) | |
848 | { | |
9257e156 MWO |
849 | return index - folio_index(folio) < folio_nr_pages(folio); |
850 | } | |
851 | ||
ec848215 MWO |
852 | /* |
853 | * Given the page we found in the page cache, return the page corresponding | |
854 | * to this index in the file | |
855 | */ | |
856 | static inline struct page *find_subpage(struct page *head, pgoff_t index) | |
4101196b | 857 | { |
ec848215 MWO |
858 | /* HugeTLBfs wants the head page regardless */ |
859 | if (PageHuge(head)) | |
860 | return head; | |
4101196b | 861 | |
6c357848 | 862 | return head + (index & (thp_nr_pages(head) - 1)); |
4101196b MWO |
863 | } |
864 | ||
be0ced5e MWO |
865 | unsigned filemap_get_folios(struct address_space *mapping, pgoff_t *start, |
866 | pgoff_t end, struct folio_batch *fbatch); | |
35b47146 VMO |
867 | unsigned filemap_get_folios_contig(struct address_space *mapping, |
868 | pgoff_t *start, pgoff_t end, struct folio_batch *fbatch); | |
247f9e1f VMO |
869 | unsigned filemap_get_folios_tag(struct address_space *mapping, pgoff_t *start, |
870 | pgoff_t end, xa_mark_t tag, struct folio_batch *fbatch); | |
1da177e4 | 871 | |
54566b2c | 872 | struct page *grab_cache_page_write_begin(struct address_space *mapping, |
b7446e7c | 873 | pgoff_t index); |
afddba49 | 874 | |
1da177e4 LT |
875 | /* |
876 | * Returns locked page at given index in given cache, creating it if needed. | |
877 | */ | |
57f6b96c FW |
878 | static inline struct page *grab_cache_page(struct address_space *mapping, |
879 | pgoff_t index) | |
1da177e4 LT |
880 | { |
881 | return find_or_create_page(mapping, index, mapping_gfp_mask(mapping)); | |
882 | } | |
883 | ||
539a3322 | 884 | struct folio *read_cache_folio(struct address_space *, pgoff_t index, |
e9b5b23e | 885 | filler_t *filler, struct file *file); |
3e629597 MWO |
886 | struct folio *mapping_read_folio_gfp(struct address_space *, pgoff_t index, |
887 | gfp_t flags); | |
539a3322 | 888 | struct page *read_cache_page(struct address_space *, pgoff_t index, |
e9b5b23e | 889 | filler_t *filler, struct file *file); |
0531b2aa LT |
890 | extern struct page * read_cache_page_gfp(struct address_space *mapping, |
891 | pgoff_t index, gfp_t gfp_mask); | |
1da177e4 | 892 | |
090d2b18 | 893 | static inline struct page *read_mapping_page(struct address_space *mapping, |
c14c6843 | 894 | pgoff_t index, struct file *file) |
090d2b18 | 895 | { |
c14c6843 | 896 | return read_cache_page(mapping, index, NULL, file); |
090d2b18 PE |
897 | } |
898 | ||
539a3322 | 899 | static inline struct folio *read_mapping_folio(struct address_space *mapping, |
c14c6843 | 900 | pgoff_t index, struct file *file) |
539a3322 | 901 | { |
c14c6843 | 902 | return read_cache_folio(mapping, index, NULL, file); |
539a3322 MWO |
903 | } |
904 | ||
a0f7a756 | 905 | /* |
a08c7193 | 906 | * Get the offset in PAGE_SIZE (even for hugetlb pages). |
a0f7a756 | 907 | */ |
a08c7193 | 908 | static inline pgoff_t page_to_pgoff(struct page *page) |
a0f7a756 | 909 | { |
fe3df441 | 910 | struct page *head; |
e9b61f19 | 911 | |
e9b61f19 | 912 | if (likely(!PageTransTail(page))) |
09cbfeaf | 913 | return page->index; |
e9b61f19 | 914 | |
fe3df441 | 915 | head = compound_head(page); |
e9b61f19 KS |
916 | /* |
917 | * We don't initialize ->index for tail pages: calculate based on | |
918 | * head page | |
919 | */ | |
fe3df441 | 920 | return head->index + page - head; |
a0f7a756 NH |
921 | } |
922 | ||
1da177e4 LT |
923 | /* |
924 | * Return byte-offset into filesystem object for page. | |
925 | */ | |
926 | static inline loff_t page_offset(struct page *page) | |
927 | { | |
09cbfeaf | 928 | return ((loff_t)page->index) << PAGE_SHIFT; |
1da177e4 LT |
929 | } |
930 | ||
f981c595 MG |
931 | static inline loff_t page_file_offset(struct page *page) |
932 | { | |
8cd79788 | 933 | return ((loff_t)page_index(page)) << PAGE_SHIFT; |
f981c595 MG |
934 | } |
935 | ||
352b47a6 MWO |
936 | /** |
937 | * folio_pos - Returns the byte position of this folio in its file. | |
938 | * @folio: The folio. | |
939 | */ | |
940 | static inline loff_t folio_pos(struct folio *folio) | |
941 | { | |
942 | return page_offset(&folio->page); | |
943 | } | |
944 | ||
945 | /** | |
946 | * folio_file_pos - Returns the byte position of this folio in its file. | |
947 | * @folio: The folio. | |
948 | * | |
949 | * This differs from folio_pos() for folios which belong to a swap file. | |
950 | * NFS is the only filesystem today which needs to use folio_file_pos(). | |
951 | */ | |
952 | static inline loff_t folio_file_pos(struct folio *folio) | |
953 | { | |
954 | return page_file_offset(&folio->page); | |
955 | } | |
956 | ||
f087b903 MWO |
957 | /* |
958 | * Get the offset in PAGE_SIZE (even for hugetlb folios). | |
f087b903 MWO |
959 | */ |
960 | static inline pgoff_t folio_pgoff(struct folio *folio) | |
961 | { | |
f087b903 MWO |
962 | return folio->index; |
963 | } | |
964 | ||
1da177e4 LT |
965 | static inline pgoff_t linear_page_index(struct vm_area_struct *vma, |
966 | unsigned long address) | |
967 | { | |
0fe6e20b | 968 | pgoff_t pgoff; |
0fe6e20b | 969 | pgoff = (address - vma->vm_start) >> PAGE_SHIFT; |
1da177e4 | 970 | pgoff += vma->vm_pgoff; |
09cbfeaf | 971 | return pgoff; |
1da177e4 LT |
972 | } |
973 | ||
c7510ab2 | 974 | struct wait_page_key { |
df4d4f12 | 975 | struct folio *folio; |
c7510ab2 JA |
976 | int bit_nr; |
977 | int page_match; | |
978 | }; | |
979 | ||
980 | struct wait_page_queue { | |
df4d4f12 | 981 | struct folio *folio; |
c7510ab2 JA |
982 | int bit_nr; |
983 | wait_queue_entry_t wait; | |
984 | }; | |
985 | ||
cdc8fcb4 | 986 | static inline bool wake_page_match(struct wait_page_queue *wait_page, |
c7510ab2 JA |
987 | struct wait_page_key *key) |
988 | { | |
df4d4f12 | 989 | if (wait_page->folio != key->folio) |
cdc8fcb4 | 990 | return false; |
c7510ab2 JA |
991 | key->page_match = 1; |
992 | ||
993 | if (wait_page->bit_nr != key->bit_nr) | |
cdc8fcb4 | 994 | return false; |
d1932dc3 | 995 | |
cdc8fcb4 | 996 | return true; |
d1932dc3 JA |
997 | } |
998 | ||
7c23c782 | 999 | void __folio_lock(struct folio *folio); |
af7f29d9 | 1000 | int __folio_lock_killable(struct folio *folio); |
fdc724d6 | 1001 | vm_fault_t __folio_lock_or_retry(struct folio *folio, struct vm_fault *vmf); |
4e136428 MWO |
1002 | void unlock_page(struct page *page); |
1003 | void folio_unlock(struct folio *folio); | |
1da177e4 | 1004 | |
cd125eea MWO |
1005 | /** |
1006 | * folio_trylock() - Attempt to lock a folio. | |
1007 | * @folio: The folio to attempt to lock. | |
1008 | * | |
1009 | * Sometimes it is undesirable to wait for a folio to be unlocked (eg | |
1010 | * when the locks are being taken in the wrong order, or if making | |
1011 | * progress through a batch of folios is more important than processing | |
1012 | * them in order). Usually folio_lock() is the correct function to call. | |
1013 | * | |
1014 | * Context: Any context. | |
1015 | * Return: Whether the lock was successfully acquired. | |
1016 | */ | |
7c23c782 MWO |
1017 | static inline bool folio_trylock(struct folio *folio) |
1018 | { | |
1019 | return likely(!test_and_set_bit_lock(PG_locked, folio_flags(folio, 0))); | |
1020 | } | |
1021 | ||
f4458845 AM |
1022 | /* |
1023 | * Return true if the page was successfully locked | |
1024 | */ | |
62087556 | 1025 | static inline bool trylock_page(struct page *page) |
529ae9aa | 1026 | { |
7c23c782 MWO |
1027 | return folio_trylock(page_folio(page)); |
1028 | } | |
1029 | ||
cd125eea MWO |
1030 | /** |
1031 | * folio_lock() - Lock this folio. | |
1032 | * @folio: The folio to lock. | |
1033 | * | |
1034 | * The folio lock protects against many things, probably more than it | |
1035 | * should. It is primarily held while a folio is being brought uptodate, | |
1036 | * either from its backing file or from swap. It is also held while a | |
1037 | * folio is being truncated from its address_space, so holding the lock | |
1038 | * is sufficient to keep folio->mapping stable. | |
1039 | * | |
1040 | * The folio lock is also held while write() is modifying the page to | |
1041 | * provide POSIX atomicity guarantees (as long as the write does not | |
1042 | * cross a page boundary). Other modifications to the data in the folio | |
1043 | * do not hold the folio lock and can race with writes, eg DMA and stores | |
1044 | * to mapped pages. | |
1045 | * | |
1046 | * Context: May sleep. If you need to acquire the locks of two or | |
1047 | * more folios, they must be in order of ascending index, if they are | |
1048 | * in the same address_space. If they are in different address_spaces, | |
1049 | * acquire the lock of the folio which belongs to the address_space which | |
1050 | * has the lowest address in memory first. | |
1051 | */ | |
7c23c782 MWO |
1052 | static inline void folio_lock(struct folio *folio) |
1053 | { | |
1054 | might_sleep(); | |
1055 | if (!folio_trylock(folio)) | |
1056 | __folio_lock(folio); | |
529ae9aa NP |
1057 | } |
1058 | ||
cd125eea MWO |
1059 | /** |
1060 | * lock_page() - Lock the folio containing this page. | |
1061 | * @page: The page to lock. | |
1062 | * | |
1063 | * See folio_lock() for a description of what the lock protects. | |
1064 | * This is a legacy function and new code should probably use folio_lock() | |
1065 | * instead. | |
1066 | * | |
1067 | * Context: May sleep. Pages in the same folio share a lock, so do not | |
1068 | * attempt to lock two pages which share a folio. | |
db37648c | 1069 | */ |
1da177e4 LT |
1070 | static inline void lock_page(struct page *page) |
1071 | { | |
7c23c782 | 1072 | struct folio *folio; |
1da177e4 | 1073 | might_sleep(); |
7c23c782 MWO |
1074 | |
1075 | folio = page_folio(page); | |
1076 | if (!folio_trylock(folio)) | |
1077 | __folio_lock(folio); | |
1da177e4 | 1078 | } |
db37648c | 1079 | |
cd125eea MWO |
1080 | /** |
1081 | * folio_lock_killable() - Lock this folio, interruptible by a fatal signal. | |
1082 | * @folio: The folio to lock. | |
1083 | * | |
1084 | * Attempts to lock the folio, like folio_lock(), except that the sleep | |
1085 | * to acquire the lock is interruptible by a fatal signal. | |
1086 | * | |
1087 | * Context: May sleep; see folio_lock(). | |
1088 | * Return: 0 if the lock was acquired; -EINTR if a fatal signal was received. | |
1089 | */ | |
af7f29d9 MWO |
1090 | static inline int folio_lock_killable(struct folio *folio) |
1091 | { | |
1092 | might_sleep(); | |
1093 | if (!folio_trylock(folio)) | |
1094 | return __folio_lock_killable(folio); | |
1095 | return 0; | |
1096 | } | |
1097 | ||
d065bd81 | 1098 | /* |
19672a9e | 1099 | * folio_lock_or_retry - Lock the folio, unless this would block and the |
d065bd81 | 1100 | * caller indicated that it can handle a retry. |
9a95f3cf | 1101 | * |
c1e8d7c6 | 1102 | * Return value and mmap_lock implications depend on flags; see |
9138e47e | 1103 | * __folio_lock_or_retry(). |
d065bd81 | 1104 | */ |
fdc724d6 SB |
1105 | static inline vm_fault_t folio_lock_or_retry(struct folio *folio, |
1106 | struct vm_fault *vmf) | |
d065bd81 ML |
1107 | { |
1108 | might_sleep(); | |
fdc724d6 SB |
1109 | if (!folio_trylock(folio)) |
1110 | return __folio_lock_or_retry(folio, vmf); | |
1111 | return 0; | |
d065bd81 ML |
1112 | } |
1113 | ||
1da177e4 | 1114 | /* |
101c0bf6 | 1115 | * This is exported only for folio_wait_locked/folio_wait_writeback, etc., |
74d81bfa | 1116 | * and should not be used directly. |
1da177e4 | 1117 | */ |
101c0bf6 MWO |
1118 | void folio_wait_bit(struct folio *folio, int bit_nr); |
1119 | int folio_wait_bit_killable(struct folio *folio, int bit_nr); | |
a4796e37 | 1120 | |
1da177e4 | 1121 | /* |
6baa8d60 | 1122 | * Wait for a folio to be unlocked. |
1da177e4 | 1123 | * |
6baa8d60 | 1124 | * This must be called with the caller "holding" the folio, |
cd125eea MWO |
1125 | * ie with increased folio reference count so that the folio won't |
1126 | * go away during the wait. | |
1da177e4 | 1127 | */ |
6baa8d60 MWO |
1128 | static inline void folio_wait_locked(struct folio *folio) |
1129 | { | |
1130 | if (folio_test_locked(folio)) | |
101c0bf6 | 1131 | folio_wait_bit(folio, PG_locked); |
6baa8d60 MWO |
1132 | } |
1133 | ||
1134 | static inline int folio_wait_locked_killable(struct folio *folio) | |
1135 | { | |
1136 | if (!folio_test_locked(folio)) | |
1137 | return 0; | |
101c0bf6 | 1138 | return folio_wait_bit_killable(folio, PG_locked); |
6baa8d60 MWO |
1139 | } |
1140 | ||
1da177e4 LT |
1141 | static inline void wait_on_page_locked(struct page *page) |
1142 | { | |
6baa8d60 | 1143 | folio_wait_locked(page_folio(page)); |
1da177e4 LT |
1144 | } |
1145 | ||
0b237047 | 1146 | void folio_end_read(struct folio *folio, bool success); |
19343b5b | 1147 | void wait_on_page_writeback(struct page *page); |
490e016f MWO |
1148 | void folio_wait_writeback(struct folio *folio); |
1149 | int folio_wait_writeback_killable(struct folio *folio); | |
4268b480 MWO |
1150 | void end_page_writeback(struct page *page); |
1151 | void folio_end_writeback(struct folio *folio); | |
1d1d1a76 | 1152 | void wait_for_stable_page(struct page *page); |
a49d0c50 | 1153 | void folio_wait_stable(struct folio *folio); |
203a3151 | 1154 | void __folio_mark_dirty(struct folio *folio, struct address_space *, int warn); |
566d3362 | 1155 | void folio_account_cleaned(struct folio *folio, struct bdi_writeback *wb); |
fdaf532a MWO |
1156 | void __folio_cancel_dirty(struct folio *folio); |
1157 | static inline void folio_cancel_dirty(struct folio *folio) | |
1158 | { | |
1159 | /* Avoid atomic ops, locking, etc. when not actually needed. */ | |
1160 | if (folio_test_dirty(folio)) | |
1161 | __folio_cancel_dirty(folio); | |
1162 | } | |
9350f20a MWO |
1163 | bool folio_clear_dirty_for_io(struct folio *folio); |
1164 | bool clear_page_dirty_for_io(struct page *page); | |
5ad6b2bd | 1165 | void folio_invalidate(struct folio *folio, size_t offset, size_t length); |
46de8b97 | 1166 | bool noop_dirty_folio(struct address_space *mapping, struct folio *folio); |
3a6b2162 | 1167 | |
2ec810d5 MWO |
1168 | #ifdef CONFIG_MIGRATION |
1169 | int filemap_migrate_folio(struct address_space *mapping, struct folio *dst, | |
1170 | struct folio *src, enum migrate_mode mode); | |
1171 | #else | |
1172 | #define filemap_migrate_folio NULL | |
1173 | #endif | |
b47393f8 MWO |
1174 | void folio_end_private_2(struct folio *folio); |
1175 | void folio_wait_private_2(struct folio *folio); | |
1176 | int folio_wait_private_2_killable(struct folio *folio); | |
73e10ded | 1177 | |
385e1ca5 DH |
1178 | /* |
1179 | * Add an arbitrary waiter to a page's wait queue | |
1180 | */ | |
df4d4f12 | 1181 | void folio_add_wait_queue(struct folio *folio, wait_queue_entry_t *waiter); |
385e1ca5 | 1182 | |
1da177e4 | 1183 | /* |
bb523b40 | 1184 | * Fault in userspace address range. |
1da177e4 | 1185 | */ |
bb523b40 | 1186 | size_t fault_in_writeable(char __user *uaddr, size_t size); |
da32b581 | 1187 | size_t fault_in_subpage_writeable(char __user *uaddr, size_t size); |
cdd591fc | 1188 | size_t fault_in_safe_writeable(const char __user *uaddr, size_t size); |
bb523b40 | 1189 | size_t fault_in_readable(const char __user *uaddr, size_t size); |
f56f821f | 1190 | |
529ae9aa | 1191 | int add_to_page_cache_lru(struct page *page, struct address_space *mapping, |
9dd3d069 MWO |
1192 | pgoff_t index, gfp_t gfp); |
1193 | int filemap_add_folio(struct address_space *mapping, struct folio *folio, | |
1194 | pgoff_t index, gfp_t gfp); | |
452e9e69 | 1195 | void filemap_remove_folio(struct folio *folio); |
452e9e69 | 1196 | void __filemap_remove_folio(struct folio *folio, void *shadow); |
3720dd6d | 1197 | void replace_page_cache_folio(struct folio *old, struct folio *new); |
aa65c29c | 1198 | void delete_from_page_cache_batch(struct address_space *mapping, |
51dcbdac | 1199 | struct folio_batch *fbatch); |
82c50f8b | 1200 | bool filemap_release_folio(struct folio *folio, gfp_t gfp); |
41139aa4 MWO |
1201 | loff_t mapping_seek_hole_data(struct address_space *, loff_t start, loff_t end, |
1202 | int whence); | |
529ae9aa | 1203 | |
9dd3d069 MWO |
1204 | /* Must be non-static for BPF error injection */ |
1205 | int __filemap_add_folio(struct address_space *mapping, struct folio *folio, | |
1206 | pgoff_t index, gfp_t gfp, void **shadowp); | |
1207 | ||
4bdcd1dd JA |
1208 | bool filemap_range_has_writeback(struct address_space *mapping, |
1209 | loff_t start_byte, loff_t end_byte); | |
1210 | ||
1211 | /** | |
1212 | * filemap_range_needs_writeback - check if range potentially needs writeback | |
1213 | * @mapping: address space within which to check | |
1214 | * @start_byte: offset in bytes where the range starts | |
1215 | * @end_byte: offset in bytes where the range ends (inclusive) | |
1216 | * | |
1217 | * Find at least one page in the range supplied, usually used to check if | |
1218 | * direct writing in this range will trigger a writeback. Used by O_DIRECT | |
1219 | * read/write with IOCB_NOWAIT, to see if the caller needs to do | |
1220 | * filemap_write_and_wait_range() before proceeding. | |
1221 | * | |
1222 | * Return: %true if the caller should do filemap_write_and_wait_range() before | |
1223 | * doing O_DIRECT to a page in this range, %false otherwise. | |
1224 | */ | |
1225 | static inline bool filemap_range_needs_writeback(struct address_space *mapping, | |
1226 | loff_t start_byte, | |
1227 | loff_t end_byte) | |
1228 | { | |
1229 | if (!mapping->nrpages) | |
1230 | return false; | |
1231 | if (!mapping_tagged(mapping, PAGECACHE_TAG_DIRTY) && | |
1232 | !mapping_tagged(mapping, PAGECACHE_TAG_WRITEBACK)) | |
1233 | return false; | |
1234 | return filemap_range_has_writeback(mapping, start_byte, end_byte); | |
1235 | } | |
1236 | ||
042124cc MWO |
1237 | /** |
1238 | * struct readahead_control - Describes a readahead request. | |
1239 | * | |
1240 | * A readahead request is for consecutive pages. Filesystems which | |
1241 | * implement the ->readahead method should call readahead_page() or | |
1242 | * readahead_page_batch() in a loop and attempt to start I/O against | |
1243 | * each page in the request. | |
1244 | * | |
1245 | * Most of the fields in this struct are private and should be accessed | |
1246 | * by the functions below. | |
1247 | * | |
1248 | * @file: The file, used primarily by network filesystems for authentication. | |
1249 | * May be NULL if invoked internally by the filesystem. | |
1250 | * @mapping: Readahead this filesystem object. | |
fcd9ae4f | 1251 | * @ra: File readahead state. May be NULL. |
042124cc MWO |
1252 | */ |
1253 | struct readahead_control { | |
1254 | struct file *file; | |
1255 | struct address_space *mapping; | |
fcd9ae4f | 1256 | struct file_ra_state *ra; |
042124cc MWO |
1257 | /* private: use the readahead_* accessors instead */ |
1258 | pgoff_t _index; | |
1259 | unsigned int _nr_pages; | |
1260 | unsigned int _batch_count; | |
17604240 CH |
1261 | bool _workingset; |
1262 | unsigned long _pflags; | |
042124cc MWO |
1263 | }; |
1264 | ||
fcd9ae4f MWO |
1265 | #define DEFINE_READAHEAD(ractl, f, r, m, i) \ |
1266 | struct readahead_control ractl = { \ | |
1aa83cfa MWO |
1267 | .file = f, \ |
1268 | .mapping = m, \ | |
fcd9ae4f | 1269 | .ra = r, \ |
1aa83cfa MWO |
1270 | ._index = i, \ |
1271 | } | |
1272 | ||
fefa7c47 MWO |
1273 | #define VM_READAHEAD_PAGES (SZ_128K / PAGE_SIZE) |
1274 | ||
1275 | void page_cache_ra_unbounded(struct readahead_control *, | |
1276 | unsigned long nr_to_read, unsigned long lookahead_count); | |
fcd9ae4f | 1277 | void page_cache_sync_ra(struct readahead_control *, unsigned long req_count); |
7836d999 | 1278 | void page_cache_async_ra(struct readahead_control *, struct folio *, |
fefa7c47 | 1279 | unsigned long req_count); |
3ca23644 DH |
1280 | void readahead_expand(struct readahead_control *ractl, |
1281 | loff_t new_start, size_t new_len); | |
fefa7c47 MWO |
1282 | |
1283 | /** | |
1284 | * page_cache_sync_readahead - generic file readahead | |
1285 | * @mapping: address_space which holds the pagecache and I/O vectors | |
1286 | * @ra: file_ra_state which holds the readahead state | |
1287 | * @file: Used by the filesystem for authentication. | |
1288 | * @index: Index of first page to be read. | |
1289 | * @req_count: Total number of pages being read by the caller. | |
1290 | * | |
1291 | * page_cache_sync_readahead() should be called when a cache miss happened: | |
1292 | * it will submit the read. The readahead logic may decide to piggyback more | |
1293 | * pages onto the read request if access patterns suggest it will improve | |
1294 | * performance. | |
1295 | */ | |
1296 | static inline | |
1297 | void page_cache_sync_readahead(struct address_space *mapping, | |
1298 | struct file_ra_state *ra, struct file *file, pgoff_t index, | |
1299 | unsigned long req_count) | |
1300 | { | |
fcd9ae4f MWO |
1301 | DEFINE_READAHEAD(ractl, file, ra, mapping, index); |
1302 | page_cache_sync_ra(&ractl, req_count); | |
fefa7c47 MWO |
1303 | } |
1304 | ||
1305 | /** | |
1306 | * page_cache_async_readahead - file readahead for marked pages | |
1307 | * @mapping: address_space which holds the pagecache and I/O vectors | |
1308 | * @ra: file_ra_state which holds the readahead state | |
1309 | * @file: Used by the filesystem for authentication. | |
2ebdd1df | 1310 | * @folio: The folio at @index which triggered the readahead call. |
fefa7c47 MWO |
1311 | * @index: Index of first page to be read. |
1312 | * @req_count: Total number of pages being read by the caller. | |
1313 | * | |
1314 | * page_cache_async_readahead() should be called when a page is used which | |
1315 | * is marked as PageReadahead; this is a marker to suggest that the application | |
1316 | * has used up enough of the readahead window that we should start pulling in | |
1317 | * more pages. | |
1318 | */ | |
1319 | static inline | |
1320 | void page_cache_async_readahead(struct address_space *mapping, | |
1321 | struct file_ra_state *ra, struct file *file, | |
2ebdd1df | 1322 | struct folio *folio, pgoff_t index, unsigned long req_count) |
fefa7c47 | 1323 | { |
fcd9ae4f | 1324 | DEFINE_READAHEAD(ractl, file, ra, mapping, index); |
2ebdd1df | 1325 | page_cache_async_ra(&ractl, folio, req_count); |
fefa7c47 MWO |
1326 | } |
1327 | ||
9bf70167 MWO |
1328 | static inline struct folio *__readahead_folio(struct readahead_control *ractl) |
1329 | { | |
1330 | struct folio *folio; | |
1331 | ||
1332 | BUG_ON(ractl->_batch_count > ractl->_nr_pages); | |
1333 | ractl->_nr_pages -= ractl->_batch_count; | |
1334 | ractl->_index += ractl->_batch_count; | |
1335 | ||
1336 | if (!ractl->_nr_pages) { | |
1337 | ractl->_batch_count = 0; | |
1338 | return NULL; | |
1339 | } | |
1340 | ||
1341 | folio = xa_load(&ractl->mapping->i_pages, ractl->_index); | |
1342 | VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio); | |
1343 | ractl->_batch_count = folio_nr_pages(folio); | |
1344 | ||
1345 | return folio; | |
1346 | } | |
1347 | ||
042124cc MWO |
1348 | /** |
1349 | * readahead_page - Get the next page to read. | |
9bf70167 | 1350 | * @ractl: The current readahead request. |
042124cc MWO |
1351 | * |
1352 | * Context: The page is locked and has an elevated refcount. The caller | |
1353 | * should decreases the refcount once the page has been submitted for I/O | |
1354 | * and unlock the page once all I/O to that page has completed. | |
1355 | * Return: A pointer to the next page, or %NULL if we are done. | |
1356 | */ | |
9bf70167 | 1357 | static inline struct page *readahead_page(struct readahead_control *ractl) |
042124cc | 1358 | { |
9bf70167 | 1359 | struct folio *folio = __readahead_folio(ractl); |
042124cc | 1360 | |
9bf70167 MWO |
1361 | return &folio->page; |
1362 | } | |
042124cc | 1363 | |
9bf70167 MWO |
1364 | /** |
1365 | * readahead_folio - Get the next folio to read. | |
1366 | * @ractl: The current readahead request. | |
1367 | * | |
1368 | * Context: The folio is locked. The caller should unlock the folio once | |
1369 | * all I/O to that folio has completed. | |
1370 | * Return: A pointer to the next folio, or %NULL if we are done. | |
1371 | */ | |
1372 | static inline struct folio *readahead_folio(struct readahead_control *ractl) | |
1373 | { | |
1374 | struct folio *folio = __readahead_folio(ractl); | |
042124cc | 1375 | |
9bf70167 MWO |
1376 | if (folio) |
1377 | folio_put(folio); | |
1378 | return folio; | |
042124cc MWO |
1379 | } |
1380 | ||
1381 | static inline unsigned int __readahead_batch(struct readahead_control *rac, | |
1382 | struct page **array, unsigned int array_sz) | |
1383 | { | |
1384 | unsigned int i = 0; | |
1385 | XA_STATE(xas, &rac->mapping->i_pages, 0); | |
1386 | struct page *page; | |
1387 | ||
1388 | BUG_ON(rac->_batch_count > rac->_nr_pages); | |
1389 | rac->_nr_pages -= rac->_batch_count; | |
1390 | rac->_index += rac->_batch_count; | |
1391 | rac->_batch_count = 0; | |
1392 | ||
1393 | xas_set(&xas, rac->_index); | |
1394 | rcu_read_lock(); | |
1395 | xas_for_each(&xas, page, rac->_index + rac->_nr_pages - 1) { | |
4349a83a MWO |
1396 | if (xas_retry(&xas, page)) |
1397 | continue; | |
042124cc MWO |
1398 | VM_BUG_ON_PAGE(!PageLocked(page), page); |
1399 | VM_BUG_ON_PAGE(PageTail(page), page); | |
1400 | array[i++] = page; | |
6c357848 | 1401 | rac->_batch_count += thp_nr_pages(page); |
042124cc MWO |
1402 | if (i == array_sz) |
1403 | break; | |
1404 | } | |
1405 | rcu_read_unlock(); | |
1406 | ||
1407 | return i; | |
1408 | } | |
1409 | ||
1410 | /** | |
1411 | * readahead_page_batch - Get a batch of pages to read. | |
1412 | * @rac: The current readahead request. | |
1413 | * @array: An array of pointers to struct page. | |
1414 | * | |
1415 | * Context: The pages are locked and have an elevated refcount. The caller | |
1416 | * should decreases the refcount once the page has been submitted for I/O | |
1417 | * and unlock the page once all I/O to that page has completed. | |
1418 | * Return: The number of pages placed in the array. 0 indicates the request | |
1419 | * is complete. | |
1420 | */ | |
1421 | #define readahead_page_batch(rac, array) \ | |
1422 | __readahead_batch(rac, array, ARRAY_SIZE(array)) | |
1423 | ||
1424 | /** | |
1425 | * readahead_pos - The byte offset into the file of this readahead request. | |
1426 | * @rac: The readahead request. | |
1427 | */ | |
1428 | static inline loff_t readahead_pos(struct readahead_control *rac) | |
1429 | { | |
1430 | return (loff_t)rac->_index * PAGE_SIZE; | |
1431 | } | |
1432 | ||
1433 | /** | |
1434 | * readahead_length - The number of bytes in this readahead request. | |
1435 | * @rac: The readahead request. | |
1436 | */ | |
076171a6 | 1437 | static inline size_t readahead_length(struct readahead_control *rac) |
042124cc | 1438 | { |
076171a6 | 1439 | return rac->_nr_pages * PAGE_SIZE; |
042124cc MWO |
1440 | } |
1441 | ||
1442 | /** | |
1443 | * readahead_index - The index of the first page in this readahead request. | |
1444 | * @rac: The readahead request. | |
1445 | */ | |
1446 | static inline pgoff_t readahead_index(struct readahead_control *rac) | |
1447 | { | |
1448 | return rac->_index; | |
1449 | } | |
1450 | ||
1451 | /** | |
1452 | * readahead_count - The number of pages in this readahead request. | |
1453 | * @rac: The readahead request. | |
1454 | */ | |
1455 | static inline unsigned int readahead_count(struct readahead_control *rac) | |
1456 | { | |
1457 | return rac->_nr_pages; | |
1458 | } | |
1459 | ||
32c0a6bc MWO |
1460 | /** |
1461 | * readahead_batch_length - The number of bytes in the current batch. | |
1462 | * @rac: The readahead request. | |
1463 | */ | |
076171a6 | 1464 | static inline size_t readahead_batch_length(struct readahead_control *rac) |
32c0a6bc MWO |
1465 | { |
1466 | return rac->_batch_count * PAGE_SIZE; | |
1467 | } | |
1468 | ||
b57c2cb9 FF |
1469 | static inline unsigned long dir_pages(struct inode *inode) |
1470 | { | |
09cbfeaf KS |
1471 | return (unsigned long)(inode->i_size + PAGE_SIZE - 1) >> |
1472 | PAGE_SHIFT; | |
b57c2cb9 FF |
1473 | } |
1474 | ||
f705bf84 MWO |
1475 | /** |
1476 | * folio_mkwrite_check_truncate - check if folio was truncated | |
1477 | * @folio: the folio to check | |
1478 | * @inode: the inode to check the folio against | |
1479 | * | |
1480 | * Return: the number of bytes in the folio up to EOF, | |
1481 | * or -EFAULT if the folio was truncated. | |
1482 | */ | |
1483 | static inline ssize_t folio_mkwrite_check_truncate(struct folio *folio, | |
1484 | struct inode *inode) | |
1485 | { | |
1486 | loff_t size = i_size_read(inode); | |
1487 | pgoff_t index = size >> PAGE_SHIFT; | |
1488 | size_t offset = offset_in_folio(folio, size); | |
1489 | ||
1490 | if (!folio->mapping) | |
1491 | return -EFAULT; | |
1492 | ||
1493 | /* folio is wholly inside EOF */ | |
1494 | if (folio_next_index(folio) - 1 < index) | |
1495 | return folio_size(folio); | |
1496 | /* folio is wholly past EOF */ | |
1497 | if (folio->index > index || !offset) | |
1498 | return -EFAULT; | |
1499 | /* folio is partially inside EOF */ | |
1500 | return offset; | |
1501 | } | |
1502 | ||
243145bc AG |
1503 | /** |
1504 | * page_mkwrite_check_truncate - check if page was truncated | |
1505 | * @page: the page to check | |
1506 | * @inode: the inode to check the page against | |
1507 | * | |
1508 | * Returns the number of bytes in the page up to EOF, | |
1509 | * or -EFAULT if the page was truncated. | |
1510 | */ | |
1511 | static inline int page_mkwrite_check_truncate(struct page *page, | |
1512 | struct inode *inode) | |
1513 | { | |
1514 | loff_t size = i_size_read(inode); | |
1515 | pgoff_t index = size >> PAGE_SHIFT; | |
1516 | int offset = offset_in_page(size); | |
1517 | ||
1518 | if (page->mapping != inode->i_mapping) | |
1519 | return -EFAULT; | |
1520 | ||
1521 | /* page is wholly inside EOF */ | |
1522 | if (page->index < index) | |
1523 | return PAGE_SIZE; | |
1524 | /* page is wholly past EOF */ | |
1525 | if (page->index > index || !offset) | |
1526 | return -EFAULT; | |
1527 | /* page is partially inside EOF */ | |
1528 | return offset; | |
1529 | } | |
1530 | ||
24addd84 | 1531 | /** |
9eb7c76d | 1532 | * i_blocks_per_folio - How many blocks fit in this folio. |
24addd84 | 1533 | * @inode: The inode which contains the blocks. |
9eb7c76d | 1534 | * @folio: The folio. |
24addd84 | 1535 | * |
9eb7c76d | 1536 | * If the block size is larger than the size of this folio, return zero. |
24addd84 | 1537 | * |
9eb7c76d | 1538 | * Context: The caller should hold a refcount on the folio to prevent it |
24addd84 | 1539 | * from being split. |
9eb7c76d | 1540 | * Return: The number of filesystem blocks covered by this folio. |
24addd84 | 1541 | */ |
9eb7c76d MWO |
1542 | static inline |
1543 | unsigned int i_blocks_per_folio(struct inode *inode, struct folio *folio) | |
1544 | { | |
1545 | return folio_size(folio) >> inode->i_blkbits; | |
1546 | } | |
1547 | ||
24addd84 MWO |
1548 | static inline |
1549 | unsigned int i_blocks_per_page(struct inode *inode, struct page *page) | |
1550 | { | |
9eb7c76d | 1551 | return i_blocks_per_folio(inode, page_folio(page)); |
24addd84 | 1552 | } |
1da177e4 | 1553 | #endif /* _LINUX_PAGEMAP_H */ |