Commit | Line | Data |
---|---|---|
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); |
a12c883a PB |
35 | int filemap_invalidate_pages(struct address_space *mapping, |
36 | loff_t pos, loff_t end, bool nowait); | |
3c435a0f | 37 | |
cbcc268b MWO |
38 | int write_inode_now(struct inode *, int sync); |
39 | int filemap_fdatawrite(struct address_space *); | |
40 | int filemap_flush(struct address_space *); | |
41 | int filemap_fdatawait_keep_errors(struct address_space *mapping); | |
42 | int filemap_fdatawait_range(struct address_space *, loff_t lstart, loff_t lend); | |
43 | int filemap_fdatawait_range_keep_errors(struct address_space *mapping, | |
44 | loff_t start_byte, loff_t end_byte); | |
74e797d7 DH |
45 | int filemap_invalidate_inode(struct inode *inode, bool flush, |
46 | loff_t start, loff_t end); | |
cbcc268b MWO |
47 | |
48 | static inline int filemap_fdatawait(struct address_space *mapping) | |
49 | { | |
50 | return filemap_fdatawait_range(mapping, 0, LLONG_MAX); | |
51 | } | |
52 | ||
53 | bool filemap_range_has_page(struct address_space *, loff_t lstart, loff_t lend); | |
54 | int filemap_write_and_wait_range(struct address_space *mapping, | |
55 | loff_t lstart, loff_t lend); | |
56 | int __filemap_fdatawrite_range(struct address_space *mapping, | |
57 | loff_t start, loff_t end, int sync_mode); | |
58 | int filemap_fdatawrite_range(struct address_space *mapping, | |
59 | loff_t start, loff_t end); | |
60 | int filemap_check_errors(struct address_space *mapping); | |
61 | void __filemap_set_wb_err(struct address_space *mapping, int err); | |
62 | int filemap_fdatawrite_wbc(struct address_space *mapping, | |
63 | struct writeback_control *wbc); | |
3c435a0f | 64 | int kiocb_write_and_wait(struct kiocb *iocb, size_t count); |
cbcc268b MWO |
65 | |
66 | static inline int filemap_write_and_wait(struct address_space *mapping) | |
67 | { | |
68 | return filemap_write_and_wait_range(mapping, 0, LLONG_MAX); | |
69 | } | |
70 | ||
71 | /** | |
72 | * filemap_set_wb_err - set a writeback error on an address_space | |
73 | * @mapping: mapping in which to set writeback error | |
74 | * @err: error to be set in mapping | |
75 | * | |
76 | * When writeback fails in some way, we must record that error so that | |
77 | * userspace can be informed when fsync and the like are called. We endeavor | |
78 | * to report errors on any file that was open at the time of the error. Some | |
79 | * internal callers also need to know when writeback errors have occurred. | |
80 | * | |
81 | * When a writeback error occurs, most filesystems will want to call | |
82 | * filemap_set_wb_err to record the error in the mapping so that it will be | |
83 | * automatically reported whenever fsync is called on the file. | |
84 | */ | |
85 | static inline void filemap_set_wb_err(struct address_space *mapping, int err) | |
86 | { | |
87 | /* Fastpath for common case of no error */ | |
88 | if (unlikely(err)) | |
89 | __filemap_set_wb_err(mapping, err); | |
90 | } | |
91 | ||
92 | /** | |
93 | * filemap_check_wb_err - has an error occurred since the mark was sampled? | |
94 | * @mapping: mapping to check for writeback errors | |
95 | * @since: previously-sampled errseq_t | |
96 | * | |
97 | * Grab the errseq_t value from the mapping, and see if it has changed "since" | |
98 | * the given value was sampled. | |
99 | * | |
100 | * If it has then report the latest error set, otherwise return 0. | |
101 | */ | |
102 | static inline int filemap_check_wb_err(struct address_space *mapping, | |
103 | errseq_t since) | |
104 | { | |
105 | return errseq_check(&mapping->wb_err, since); | |
106 | } | |
107 | ||
108 | /** | |
109 | * filemap_sample_wb_err - sample the current errseq_t to test for later errors | |
110 | * @mapping: mapping to be sampled | |
111 | * | |
112 | * Writeback errors are always reported relative to a particular sample point | |
113 | * in the past. This function provides those sample points. | |
114 | */ | |
115 | static inline errseq_t filemap_sample_wb_err(struct address_space *mapping) | |
116 | { | |
117 | return errseq_sample(&mapping->wb_err); | |
118 | } | |
119 | ||
120 | /** | |
121 | * file_sample_sb_err - sample the current errseq_t to test for later errors | |
122 | * @file: file pointer to be sampled | |
123 | * | |
124 | * Grab the most current superblock-level errseq_t value for the given | |
125 | * struct file. | |
126 | */ | |
127 | static inline errseq_t file_sample_sb_err(struct file *file) | |
128 | { | |
129 | return errseq_sample(&file->f_path.dentry->d_sb->s_wb_err); | |
130 | } | |
131 | ||
132 | /* | |
133 | * Flush file data before changing attributes. Caller must hold any locks | |
134 | * required to prevent further writes to this file until we're done setting | |
135 | * flags. | |
136 | */ | |
137 | static inline int inode_drain_writes(struct inode *inode) | |
138 | { | |
139 | inode_dio_wait(inode); | |
140 | return filemap_write_and_wait(inode->i_mapping); | |
141 | } | |
142 | ||
7716506a MWO |
143 | static inline bool mapping_empty(struct address_space *mapping) |
144 | { | |
145 | return xa_empty(&mapping->i_pages); | |
146 | } | |
147 | ||
51b8c1fe JW |
148 | /* |
149 | * mapping_shrinkable - test if page cache state allows inode reclaim | |
150 | * @mapping: the page cache mapping | |
151 | * | |
152 | * This checks the mapping's cache state for the pupose of inode | |
153 | * reclaim and LRU management. | |
154 | * | |
155 | * The caller is expected to hold the i_lock, but is not required to | |
156 | * hold the i_pages lock, which usually protects cache state. That's | |
157 | * because the i_lock and the list_lru lock that protect the inode and | |
158 | * its LRU state don't nest inside the irq-safe i_pages lock. | |
159 | * | |
160 | * Cache deletions are performed under the i_lock, which ensures that | |
161 | * when an inode goes empty, it will reliably get queued on the LRU. | |
162 | * | |
163 | * Cache additions do not acquire the i_lock and may race with this | |
164 | * check, in which case we'll report the inode as shrinkable when it | |
165 | * has cache pages. This is okay: the shrinker also checks the | |
166 | * refcount and the referenced bit, which will be elevated or set in | |
167 | * the process of adding new cache pages to an inode. | |
168 | */ | |
169 | static inline bool mapping_shrinkable(struct address_space *mapping) | |
170 | { | |
171 | void *head; | |
172 | ||
173 | /* | |
174 | * On highmem systems, there could be lowmem pressure from the | |
175 | * inodes before there is highmem pressure from the page | |
176 | * cache. Make inodes shrinkable regardless of cache state. | |
177 | */ | |
178 | if (IS_ENABLED(CONFIG_HIGHMEM)) | |
179 | return true; | |
180 | ||
181 | /* Cache completely empty? Shrink away. */ | |
182 | head = rcu_access_pointer(mapping->i_pages.xa_head); | |
183 | if (!head) | |
184 | return true; | |
185 | ||
186 | /* | |
187 | * The xarray stores single offset-0 entries directly in the | |
188 | * head pointer, which allows non-resident page cache entries | |
189 | * to escape the shadow shrinker's list of xarray nodes. The | |
190 | * inode shrinker needs to pick them up under memory pressure. | |
191 | */ | |
192 | if (!xa_is_node(head) && xa_is_value(head)) | |
193 | return true; | |
194 | ||
195 | return false; | |
196 | } | |
197 | ||
1da177e4 | 198 | /* |
9c5d760b | 199 | * Bits in mapping->flags. |
1da177e4 | 200 | */ |
9a896c9a | 201 | enum mapping_flags { |
9c5d760b MH |
202 | AS_EIO = 0, /* IO error on async write */ |
203 | AS_ENOSPC = 1, /* ENOSPC on async write */ | |
204 | AS_MM_ALL_LOCKS = 2, /* under mm_take_all_locks() */ | |
205 | AS_UNEVICTABLE = 3, /* e.g., ramdisk, SHM_LOCK */ | |
206 | AS_EXITING = 4, /* final truncate in progress */ | |
371a096e | 207 | /* writeback related tags are not used */ |
9c5d760b | 208 | AS_NO_WRITEBACK_TAGS = 5, |
84429b67 MWO |
209 | AS_RELEASE_ALWAYS = 6, /* Call ->release_folio(), even if no private data */ |
210 | AS_STABLE_WRITES = 7, /* must wait for writeback before modifying | |
762321da | 211 | folio contents */ |
84429b67 MWO |
212 | AS_INACCESSIBLE = 8, /* Do not attempt direct R/W access to the mapping */ |
213 | /* Bits 16-25 are used for FOLIO_ORDER */ | |
214 | AS_FOLIO_ORDER_BITS = 5, | |
215 | AS_FOLIO_ORDER_MIN = 16, | |
216 | AS_FOLIO_ORDER_MAX = AS_FOLIO_ORDER_MIN + AS_FOLIO_ORDER_BITS, | |
9a896c9a | 217 | }; |
1da177e4 | 218 | |
84429b67 MWO |
219 | #define AS_FOLIO_ORDER_BITS_MASK ((1u << AS_FOLIO_ORDER_BITS) - 1) |
220 | #define AS_FOLIO_ORDER_MIN_MASK (AS_FOLIO_ORDER_BITS_MASK << AS_FOLIO_ORDER_MIN) | |
221 | #define AS_FOLIO_ORDER_MAX_MASK (AS_FOLIO_ORDER_BITS_MASK << AS_FOLIO_ORDER_MAX) | |
222 | #define AS_FOLIO_ORDER_MASK (AS_FOLIO_ORDER_MIN_MASK | AS_FOLIO_ORDER_MAX_MASK) | |
223 | ||
8ed1e46a JL |
224 | /** |
225 | * mapping_set_error - record a writeback error in the address_space | |
767e5ee5 MWO |
226 | * @mapping: the mapping in which an error should be set |
227 | * @error: the error to set in the mapping | |
8ed1e46a JL |
228 | * |
229 | * When writeback fails in some way, we must record that error so that | |
230 | * userspace can be informed when fsync and the like are called. We endeavor | |
231 | * to report errors on any file that was open at the time of the error. Some | |
232 | * internal callers also need to know when writeback errors have occurred. | |
233 | * | |
234 | * When a writeback error occurs, most filesystems will want to call | |
235 | * mapping_set_error to record the error in the mapping so that it can be | |
236 | * reported when the application calls fsync(2). | |
237 | */ | |
3e9f45bd GC |
238 | static inline void mapping_set_error(struct address_space *mapping, int error) |
239 | { | |
8ed1e46a JL |
240 | if (likely(!error)) |
241 | return; | |
242 | ||
243 | /* Record in wb_err for checkers using errseq_t based tracking */ | |
735e4ae5 JL |
244 | __filemap_set_wb_err(mapping, error); |
245 | ||
246 | /* Record it in superblock */ | |
8b7b2eb1 MK |
247 | if (mapping->host) |
248 | errseq_set(&mapping->host->i_sb->s_wb_err, error); | |
8ed1e46a JL |
249 | |
250 | /* Record it in flags for now, for legacy callers */ | |
251 | if (error == -ENOSPC) | |
252 | set_bit(AS_ENOSPC, &mapping->flags); | |
253 | else | |
254 | set_bit(AS_EIO, &mapping->flags); | |
3e9f45bd GC |
255 | } |
256 | ||
ba9ddf49 LS |
257 | static inline void mapping_set_unevictable(struct address_space *mapping) |
258 | { | |
259 | set_bit(AS_UNEVICTABLE, &mapping->flags); | |
260 | } | |
261 | ||
89e004ea LS |
262 | static inline void mapping_clear_unevictable(struct address_space *mapping) |
263 | { | |
264 | clear_bit(AS_UNEVICTABLE, &mapping->flags); | |
265 | } | |
266 | ||
1eb6234e | 267 | static inline bool mapping_unevictable(struct address_space *mapping) |
ba9ddf49 | 268 | { |
1eb6234e | 269 | return mapping && test_bit(AS_UNEVICTABLE, &mapping->flags); |
ba9ddf49 | 270 | } |
ba9ddf49 | 271 | |
91b0abe3 JW |
272 | static inline void mapping_set_exiting(struct address_space *mapping) |
273 | { | |
274 | set_bit(AS_EXITING, &mapping->flags); | |
275 | } | |
276 | ||
277 | static inline int mapping_exiting(struct address_space *mapping) | |
278 | { | |
279 | return test_bit(AS_EXITING, &mapping->flags); | |
280 | } | |
281 | ||
371a096e HY |
282 | static inline void mapping_set_no_writeback_tags(struct address_space *mapping) |
283 | { | |
284 | set_bit(AS_NO_WRITEBACK_TAGS, &mapping->flags); | |
285 | } | |
286 | ||
287 | static inline int mapping_use_writeback_tags(struct address_space *mapping) | |
288 | { | |
289 | return !test_bit(AS_NO_WRITEBACK_TAGS, &mapping->flags); | |
290 | } | |
291 | ||
b4fa966f DH |
292 | static inline bool mapping_release_always(const struct address_space *mapping) |
293 | { | |
294 | return test_bit(AS_RELEASE_ALWAYS, &mapping->flags); | |
295 | } | |
296 | ||
297 | static inline void mapping_set_release_always(struct address_space *mapping) | |
298 | { | |
299 | set_bit(AS_RELEASE_ALWAYS, &mapping->flags); | |
300 | } | |
301 | ||
302 | static inline void mapping_clear_release_always(struct address_space *mapping) | |
303 | { | |
304 | clear_bit(AS_RELEASE_ALWAYS, &mapping->flags); | |
305 | } | |
306 | ||
762321da CH |
307 | static inline bool mapping_stable_writes(const struct address_space *mapping) |
308 | { | |
309 | return test_bit(AS_STABLE_WRITES, &mapping->flags); | |
310 | } | |
311 | ||
312 | static inline void mapping_set_stable_writes(struct address_space *mapping) | |
313 | { | |
314 | set_bit(AS_STABLE_WRITES, &mapping->flags); | |
315 | } | |
316 | ||
317 | static inline void mapping_clear_stable_writes(struct address_space *mapping) | |
318 | { | |
319 | clear_bit(AS_STABLE_WRITES, &mapping->flags); | |
320 | } | |
321 | ||
27e6a24a | 322 | static inline void mapping_set_inaccessible(struct address_space *mapping) |
0003e2a4 SC |
323 | { |
324 | /* | |
27e6a24a | 325 | * It's expected inaccessible mappings are also unevictable. Compaction |
0003e2a4 SC |
326 | * migrate scanner (isolate_migratepages_block()) relies on this to |
327 | * reduce page locking. | |
328 | */ | |
329 | set_bit(AS_UNEVICTABLE, &mapping->flags); | |
27e6a24a | 330 | set_bit(AS_INACCESSIBLE, &mapping->flags); |
0003e2a4 SC |
331 | } |
332 | ||
27e6a24a | 333 | static inline bool mapping_inaccessible(struct address_space *mapping) |
0003e2a4 | 334 | { |
27e6a24a | 335 | return test_bit(AS_INACCESSIBLE, &mapping->flags); |
0003e2a4 SC |
336 | } |
337 | ||
dd0fc66f | 338 | static inline gfp_t mapping_gfp_mask(struct address_space * mapping) |
1da177e4 | 339 | { |
9c5d760b | 340 | return mapping->gfp_mask; |
1da177e4 LT |
341 | } |
342 | ||
c62d2555 MH |
343 | /* Restricts the given gfp_mask to what the mapping allows. */ |
344 | static inline gfp_t mapping_gfp_constraint(struct address_space *mapping, | |
345 | gfp_t gfp_mask) | |
346 | { | |
347 | return mapping_gfp_mask(mapping) & gfp_mask; | |
348 | } | |
349 | ||
1da177e4 LT |
350 | /* |
351 | * This is non-atomic. Only to be used before the mapping is activated. | |
352 | * Probably needs a barrier... | |
353 | */ | |
260b2367 | 354 | static inline void mapping_set_gfp_mask(struct address_space *m, gfp_t mask) |
1da177e4 | 355 | { |
9c5d760b | 356 | m->gfp_mask = mask; |
1da177e4 LT |
357 | } |
358 | ||
79c13745 XY |
359 | /* |
360 | * There are some parts of the kernel which assume that PMD entries | |
361 | * are exactly HPAGE_PMD_ORDER. Those should be fixed, but until then, | |
362 | * limit the maximum allocation order to PMD size. I'm not aware of any | |
363 | * assumptions about maximum order if THP are disabled, but 8 seems like | |
364 | * a good order (that's 1MB if you're using 4kB pages) | |
365 | */ | |
366 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE | |
099d9064 | 367 | #define PREFERRED_MAX_PAGECACHE_ORDER HPAGE_PMD_ORDER |
79c13745 | 368 | #else |
099d9064 | 369 | #define PREFERRED_MAX_PAGECACHE_ORDER 8 |
79c13745 XY |
370 | #endif |
371 | ||
099d9064 GS |
372 | /* |
373 | * xas_split_alloc() does not support arbitrary orders. This implies no | |
374 | * 512MB THP on ARM64 with 64KB base page size. | |
375 | */ | |
376 | #define MAX_XAS_ORDER (XA_CHUNK_SHIFT * 2 - 1) | |
377 | #define MAX_PAGECACHE_ORDER min(MAX_XAS_ORDER, PREFERRED_MAX_PAGECACHE_ORDER) | |
378 | ||
7df7c204 PR |
379 | /* |
380 | * mapping_max_folio_size_supported() - Check the max folio size supported | |
381 | * | |
382 | * The filesystem should call this function at mount time if there is a | |
383 | * requirement on the folio mapping size in the page cache. | |
384 | */ | |
385 | static inline size_t mapping_max_folio_size_supported(void) | |
386 | { | |
387 | if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) | |
388 | return 1U << (PAGE_SHIFT + MAX_PAGECACHE_ORDER); | |
389 | return PAGE_SIZE; | |
390 | } | |
391 | ||
84429b67 MWO |
392 | /* |
393 | * mapping_set_folio_order_range() - Set the orders supported by a file. | |
394 | * @mapping: The address space of the file. | |
395 | * @min: Minimum folio order (between 0-MAX_PAGECACHE_ORDER inclusive). | |
396 | * @max: Maximum folio order (between @min-MAX_PAGECACHE_ORDER inclusive). | |
397 | * | |
398 | * The filesystem should call this function in its inode constructor to | |
399 | * indicate which base size (min) and maximum size (max) of folio the VFS | |
400 | * can use to cache the contents of the file. This should only be used | |
401 | * if the filesystem needs special handling of folio sizes (ie there is | |
402 | * something the core cannot know). | |
403 | * Do not tune it based on, eg, i_size. | |
404 | * | |
405 | * Context: This should not be called while the inode is active as it | |
406 | * is non-atomic. | |
407 | */ | |
408 | static inline void mapping_set_folio_order_range(struct address_space *mapping, | |
409 | unsigned int min, | |
410 | unsigned int max) | |
411 | { | |
412 | if (!IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) | |
413 | return; | |
414 | ||
415 | if (min > MAX_PAGECACHE_ORDER) | |
416 | min = MAX_PAGECACHE_ORDER; | |
417 | ||
418 | if (max > MAX_PAGECACHE_ORDER) | |
419 | max = MAX_PAGECACHE_ORDER; | |
420 | ||
421 | if (max < min) | |
422 | max = min; | |
423 | ||
424 | mapping->flags = (mapping->flags & ~AS_FOLIO_ORDER_MASK) | | |
425 | (min << AS_FOLIO_ORDER_MIN) | (max << AS_FOLIO_ORDER_MAX); | |
426 | } | |
427 | ||
428 | static inline void mapping_set_folio_min_order(struct address_space *mapping, | |
429 | unsigned int min) | |
430 | { | |
431 | mapping_set_folio_order_range(mapping, min, MAX_PAGECACHE_ORDER); | |
432 | } | |
433 | ||
ff36da69 MWO |
434 | /** |
435 | * mapping_set_large_folios() - Indicate the file supports large folios. | |
84429b67 | 436 | * @mapping: The address space of the file. |
ff36da69 MWO |
437 | * |
438 | * The filesystem should call this function in its inode constructor to | |
439 | * indicate that the VFS can use large folios to cache the contents of | |
440 | * the file. | |
441 | * | |
442 | * Context: This should not be called while the inode is active as it | |
443 | * is non-atomic. | |
444 | */ | |
445 | static inline void mapping_set_large_folios(struct address_space *mapping) | |
446 | { | |
84429b67 MWO |
447 | mapping_set_folio_order_range(mapping, 0, MAX_PAGECACHE_ORDER); |
448 | } | |
449 | ||
450 | static inline unsigned int | |
451 | mapping_max_folio_order(const struct address_space *mapping) | |
452 | { | |
453 | if (!IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) | |
454 | return 0; | |
455 | return (mapping->flags & AS_FOLIO_ORDER_MAX_MASK) >> AS_FOLIO_ORDER_MAX; | |
456 | } | |
457 | ||
458 | static inline unsigned int | |
459 | mapping_min_folio_order(const struct address_space *mapping) | |
460 | { | |
461 | if (!IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) | |
462 | return 0; | |
463 | return (mapping->flags & AS_FOLIO_ORDER_MIN_MASK) >> AS_FOLIO_ORDER_MIN; | |
ff36da69 MWO |
464 | } |
465 | ||
ab95d23b PR |
466 | static inline unsigned long |
467 | mapping_min_folio_nrpages(struct address_space *mapping) | |
468 | { | |
469 | return 1UL << mapping_min_folio_order(mapping); | |
470 | } | |
471 | ||
472 | /** | |
473 | * mapping_align_index() - Align index for this mapping. | |
474 | * @mapping: The address_space. | |
6f634eb0 | 475 | * @index: The page index. |
ab95d23b PR |
476 | * |
477 | * The index of a folio must be naturally aligned. If you are adding a | |
478 | * new folio to the page cache and need to know what index to give it, | |
479 | * call this function. | |
480 | */ | |
481 | static inline pgoff_t mapping_align_index(struct address_space *mapping, | |
482 | pgoff_t index) | |
483 | { | |
484 | return round_down(index, mapping_min_folio_nrpages(mapping)); | |
ff36da69 MWO |
485 | } |
486 | ||
421f1ab4 MWO |
487 | /* |
488 | * Large folio support currently depends on THP. These dependencies are | |
489 | * being worked on but are not yet fixed. | |
490 | */ | |
ed2145c4 | 491 | static inline bool mapping_large_folio_support(struct address_space *mapping) |
01c70267 | 492 | { |
84429b67 | 493 | /* AS_FOLIO_ORDER is only reasonable for pagecache folios */ |
6a50c9b5 RX |
494 | VM_WARN_ONCE((unsigned long)mapping & PAGE_MAPPING_ANON, |
495 | "Anonymous mapping always supports large folio"); | |
496 | ||
84429b67 | 497 | return mapping_max_folio_order(mapping) > 0; |
01c70267 MWO |
498 | } |
499 | ||
79c13745 | 500 | /* Return the maximum folio size for this pagecache mapping, in bytes. */ |
84429b67 | 501 | static inline size_t mapping_max_folio_size(const struct address_space *mapping) |
79c13745 | 502 | { |
84429b67 | 503 | return PAGE_SIZE << mapping_max_folio_order(mapping); |
79c13745 XY |
504 | } |
505 | ||
6f4d2f97 MWO |
506 | static inline int filemap_nr_thps(struct address_space *mapping) |
507 | { | |
508 | #ifdef CONFIG_READ_ONLY_THP_FOR_FS | |
509 | return atomic_read(&mapping->nr_thps); | |
510 | #else | |
511 | return 0; | |
512 | #endif | |
513 | } | |
514 | ||
515 | static inline void filemap_nr_thps_inc(struct address_space *mapping) | |
516 | { | |
517 | #ifdef CONFIG_READ_ONLY_THP_FOR_FS | |
ed2145c4 | 518 | if (!mapping_large_folio_support(mapping)) |
6f4d2f97 MWO |
519 | atomic_inc(&mapping->nr_thps); |
520 | #else | |
06d44142 | 521 | WARN_ON_ONCE(mapping_large_folio_support(mapping) == 0); |
6f4d2f97 MWO |
522 | #endif |
523 | } | |
524 | ||
525 | static inline void filemap_nr_thps_dec(struct address_space *mapping) | |
526 | { | |
527 | #ifdef CONFIG_READ_ONLY_THP_FOR_FS | |
ed2145c4 | 528 | if (!mapping_large_folio_support(mapping)) |
6f4d2f97 MWO |
529 | atomic_dec(&mapping->nr_thps); |
530 | #else | |
06d44142 | 531 | WARN_ON_ONCE(mapping_large_folio_support(mapping) == 0); |
6f4d2f97 MWO |
532 | #endif |
533 | } | |
534 | ||
2f52578f MWO |
535 | struct address_space *folio_mapping(struct folio *); |
536 | struct address_space *swapcache_mapping(struct folio *); | |
537 | ||
538 | /** | |
539 | * folio_file_mapping - Find the mapping this folio belongs to. | |
540 | * @folio: The folio. | |
541 | * | |
542 | * For folios which are in the page cache, return the mapping that this | |
543 | * page belongs to. Folios in the swap cache return the mapping of the | |
544 | * swap file or swap device where the data is stored. This is different | |
545 | * from the mapping returned by folio_mapping(). The only reason to | |
546 | * use it is if, like NFS, you return 0 from ->activate_swapfile. | |
547 | * | |
548 | * Do not call this for folios which aren't in the page cache or swap cache. | |
549 | */ | |
550 | static inline struct address_space *folio_file_mapping(struct folio *folio) | |
551 | { | |
552 | if (unlikely(folio_test_swapcache(folio))) | |
553 | return swapcache_mapping(folio); | |
554 | ||
555 | return folio->mapping; | |
556 | } | |
557 | ||
bc60abfb MWO |
558 | /** |
559 | * folio_flush_mapping - Find the file mapping this folio belongs to. | |
560 | * @folio: The folio. | |
561 | * | |
562 | * For folios which are in the page cache, return the mapping that this | |
563 | * page belongs to. Anonymous folios return NULL, even if they're in | |
564 | * the swap cache. Other kinds of folio also return NULL. | |
565 | * | |
566 | * This is ONLY used by architecture cache flushing code. If you aren't | |
567 | * writing cache flushing code, you want either folio_mapping() or | |
568 | * folio_file_mapping(). | |
842ca547 | 569 | */ |
bc60abfb | 570 | static inline struct address_space *folio_flush_mapping(struct folio *folio) |
842ca547 | 571 | { |
2f52578f | 572 | if (unlikely(folio_test_swapcache(folio))) |
842ca547 | 573 | return NULL; |
bc60abfb | 574 | |
2f52578f | 575 | return folio_mapping(folio); |
842ca547 MWO |
576 | } |
577 | ||
2f52578f MWO |
578 | static inline struct address_space *page_file_mapping(struct page *page) |
579 | { | |
580 | return folio_file_mapping(page_folio(page)); | |
842ca547 MWO |
581 | } |
582 | ||
452c472e DH |
583 | /** |
584 | * folio_inode - Get the host inode for this folio. | |
585 | * @folio: The folio. | |
586 | * | |
587 | * For folios which are in the page cache, return the inode that this folio | |
588 | * belongs to. | |
589 | * | |
590 | * Do not call this for folios which aren't in the page cache. | |
591 | */ | |
592 | static inline struct inode *folio_inode(struct folio *folio) | |
593 | { | |
594 | return folio->mapping->host; | |
595 | } | |
596 | ||
b03143ac | 597 | /** |
85d0a2ed MWO |
598 | * folio_attach_private - Attach private data to a folio. |
599 | * @folio: Folio to attach data to. | |
600 | * @data: Data to attach to folio. | |
b03143ac | 601 | * |
85d0a2ed MWO |
602 | * Attaching private data to a folio increments the page's reference count. |
603 | * The data must be detached before the folio will be freed. | |
b03143ac | 604 | */ |
85d0a2ed | 605 | static inline void folio_attach_private(struct folio *folio, void *data) |
b03143ac | 606 | { |
85d0a2ed MWO |
607 | folio_get(folio); |
608 | folio->private = data; | |
609 | folio_set_private(folio); | |
b03143ac GJ |
610 | } |
611 | ||
a19672f6 DH |
612 | /** |
613 | * folio_change_private - Change private data on a folio. | |
614 | * @folio: Folio to change the data on. | |
615 | * @data: Data to set on the folio. | |
616 | * | |
617 | * Change the private data attached to a folio and return the old | |
618 | * data. The page must previously have had data attached and the data | |
619 | * must be detached before the folio will be freed. | |
620 | * | |
621 | * Return: Data that was previously attached to the folio. | |
622 | */ | |
623 | static inline void *folio_change_private(struct folio *folio, void *data) | |
624 | { | |
625 | void *old = folio_get_private(folio); | |
626 | ||
627 | folio->private = data; | |
628 | return old; | |
629 | } | |
630 | ||
b03143ac | 631 | /** |
85d0a2ed MWO |
632 | * folio_detach_private - Detach private data from a folio. |
633 | * @folio: Folio to detach data from. | |
b03143ac | 634 | * |
85d0a2ed | 635 | * Removes the data that was previously attached to the folio and decrements |
b03143ac GJ |
636 | * the refcount on the page. |
637 | * | |
85d0a2ed | 638 | * Return: Data that was attached to the folio. |
b03143ac | 639 | */ |
85d0a2ed | 640 | static inline void *folio_detach_private(struct folio *folio) |
b03143ac | 641 | { |
85d0a2ed | 642 | void *data = folio_get_private(folio); |
b03143ac | 643 | |
85d0a2ed | 644 | if (!folio_test_private(folio)) |
b03143ac | 645 | return NULL; |
85d0a2ed MWO |
646 | folio_clear_private(folio); |
647 | folio->private = NULL; | |
648 | folio_put(folio); | |
b03143ac GJ |
649 | |
650 | return data; | |
651 | } | |
652 | ||
85d0a2ed MWO |
653 | static inline void attach_page_private(struct page *page, void *data) |
654 | { | |
655 | folio_attach_private(page_folio(page), data); | |
656 | } | |
657 | ||
658 | static inline void *detach_page_private(struct page *page) | |
659 | { | |
660 | return folio_detach_private(page_folio(page)); | |
661 | } | |
662 | ||
44110fe3 | 663 | #ifdef CONFIG_NUMA |
b951aaff | 664 | struct folio *filemap_alloc_folio_noprof(gfp_t gfp, unsigned int order); |
44110fe3 | 665 | #else |
b951aaff | 666 | static inline struct folio *filemap_alloc_folio_noprof(gfp_t gfp, unsigned int order) |
2ae88149 | 667 | { |
b951aaff | 668 | return folio_alloc_noprof(gfp, order); |
2ae88149 NP |
669 | } |
670 | #endif | |
671 | ||
b951aaff SB |
672 | #define filemap_alloc_folio(...) \ |
673 | alloc_hooks(filemap_alloc_folio_noprof(__VA_ARGS__)) | |
674 | ||
bb3c579e MWO |
675 | static inline struct page *__page_cache_alloc(gfp_t gfp) |
676 | { | |
677 | return &filemap_alloc_folio(gfp, 0)->page; | |
678 | } | |
679 | ||
8a5c743e | 680 | static inline gfp_t readahead_gfp_mask(struct address_space *x) |
7b1de586 | 681 | { |
453f85d4 | 682 | return mapping_gfp_mask(x) | __GFP_NORETRY | __GFP_NOWARN; |
7b1de586 WF |
683 | } |
684 | ||
e9b5b23e | 685 | typedef int filler_t(struct file *, struct folio *); |
1da177e4 | 686 | |
0d3f9296 | 687 | pgoff_t page_cache_next_miss(struct address_space *mapping, |
e7b563bb | 688 | pgoff_t index, unsigned long max_scan); |
0d3f9296 | 689 | pgoff_t page_cache_prev_miss(struct address_space *mapping, |
e7b563bb JW |
690 | pgoff_t index, unsigned long max_scan); |
691 | ||
ffc143db MWO |
692 | /** |
693 | * typedef fgf_t - Flags for getting folios from the page cache. | |
694 | * | |
695 | * Most users of the page cache will not need to use these flags; | |
696 | * there are convenience functions such as filemap_get_folio() and | |
697 | * filemap_lock_folio(). For users which need more control over exactly | |
698 | * what is done with the folios, these flags to __filemap_get_folio() | |
699 | * are available. | |
700 | * | |
701 | * * %FGP_ACCESSED - The folio will be marked accessed. | |
702 | * * %FGP_LOCK - The folio is returned locked. | |
703 | * * %FGP_CREAT - If no folio is present then a new folio is allocated, | |
704 | * added to the page cache and the VM's LRU list. The folio is | |
705 | * returned locked. | |
706 | * * %FGP_FOR_MMAP - The caller wants to do its own locking dance if the | |
707 | * folio is already in cache. If the folio was allocated, unlock it | |
708 | * before returning so the caller can do the same dance. | |
709 | * * %FGP_WRITE - The folio will be written to by the caller. | |
710 | * * %FGP_NOFS - __GFP_FS will get cleared in gfp. | |
711 | * * %FGP_NOWAIT - Don't block on the folio lock. | |
712 | * * %FGP_STABLE - Wait for the folio to be stable (finished writeback) | |
713 | * * %FGP_WRITEBEGIN - The flags to use in a filesystem write_begin() | |
714 | * implementation. | |
715 | */ | |
716 | typedef unsigned int __bitwise fgf_t; | |
717 | ||
718 | #define FGP_ACCESSED ((__force fgf_t)0x00000001) | |
719 | #define FGP_LOCK ((__force fgf_t)0x00000002) | |
720 | #define FGP_CREAT ((__force fgf_t)0x00000004) | |
721 | #define FGP_WRITE ((__force fgf_t)0x00000008) | |
722 | #define FGP_NOFS ((__force fgf_t)0x00000010) | |
723 | #define FGP_NOWAIT ((__force fgf_t)0x00000020) | |
724 | #define FGP_FOR_MMAP ((__force fgf_t)0x00000040) | |
725 | #define FGP_STABLE ((__force fgf_t)0x00000080) | |
4f661701 | 726 | #define FGF_GET_ORDER(fgf) (((__force unsigned)fgf) >> 26) /* top 6 bits */ |
2457aec6 | 727 | |
e999a5c5 MW |
728 | #define FGP_WRITEBEGIN (FGP_LOCK | FGP_WRITE | FGP_CREAT | FGP_STABLE) |
729 | ||
4f661701 MWO |
730 | /** |
731 | * fgf_set_order - Encode a length in the fgf_t flags. | |
732 | * @size: The suggested size of the folio to create. | |
733 | * | |
734 | * The caller of __filemap_get_folio() can use this to suggest a preferred | |
735 | * size for the folio that is created. If there is already a folio at | |
736 | * the index, it will be returned, no matter what its size. If a folio | |
737 | * is freshly created, it may be of a different size than requested | |
738 | * due to alignment constraints, memory pressure, or the presence of | |
739 | * other folios at nearby indices. | |
740 | */ | |
741 | static inline fgf_t fgf_set_order(size_t size) | |
742 | { | |
743 | unsigned int shift = ilog2(size); | |
744 | ||
745 | if (shift <= PAGE_SHIFT) | |
746 | return 0; | |
747 | return (__force fgf_t)((shift - PAGE_SHIFT) << 26); | |
748 | } | |
749 | ||
263e721e | 750 | void *filemap_get_entry(struct address_space *mapping, pgoff_t index); |
3f0c6a07 | 751 | struct folio *__filemap_get_folio(struct address_space *mapping, pgoff_t index, |
ffc143db | 752 | fgf_t fgp_flags, gfp_t gfp); |
3f0c6a07 | 753 | struct page *pagecache_get_page(struct address_space *mapping, pgoff_t index, |
ffc143db | 754 | fgf_t fgp_flags, gfp_t gfp); |
3f0c6a07 MWO |
755 | |
756 | /** | |
757 | * filemap_get_folio - Find and get a folio. | |
758 | * @mapping: The address_space to search. | |
759 | * @index: The page index. | |
760 | * | |
761 | * Looks up the page cache entry at @mapping & @index. If a folio is | |
762 | * present, it is returned with an increased refcount. | |
763 | * | |
66dabbb6 CH |
764 | * Return: A folio or ERR_PTR(-ENOENT) if there is no folio in the cache for |
765 | * this index. Will not return a shadow, swap or DAX entry. | |
3f0c6a07 MWO |
766 | */ |
767 | static inline struct folio *filemap_get_folio(struct address_space *mapping, | |
768 | pgoff_t index) | |
769 | { | |
770 | return __filemap_get_folio(mapping, index, 0, 0); | |
771 | } | |
2457aec6 | 772 | |
ccd16945 MWO |
773 | /** |
774 | * filemap_lock_folio - Find and lock a folio. | |
775 | * @mapping: The address_space to search. | |
776 | * @index: The page index. | |
777 | * | |
778 | * Looks up the page cache entry at @mapping & @index. If a folio is | |
779 | * present, it is returned locked with an increased refcount. | |
780 | * | |
781 | * Context: May sleep. | |
66dabbb6 CH |
782 | * Return: A folio or ERR_PTR(-ENOENT) if there is no folio in the cache for |
783 | * this index. Will not return a shadow, swap or DAX entry. | |
ccd16945 MWO |
784 | */ |
785 | static inline struct folio *filemap_lock_folio(struct address_space *mapping, | |
786 | pgoff_t index) | |
787 | { | |
788 | return __filemap_get_folio(mapping, index, FGP_LOCK, 0); | |
789 | } | |
790 | ||
ee7a5906 VMO |
791 | /** |
792 | * filemap_grab_folio - grab a folio from the page cache | |
793 | * @mapping: The address space to search | |
794 | * @index: The page index | |
795 | * | |
796 | * Looks up the page cache entry at @mapping & @index. If no folio is found, | |
797 | * a new folio is created. The folio is locked, marked as accessed, and | |
798 | * returned. | |
799 | * | |
66dabbb6 CH |
800 | * Return: A found or created folio. ERR_PTR(-ENOMEM) if no folio is found |
801 | * and failed to create a folio. | |
ee7a5906 VMO |
802 | */ |
803 | static inline struct folio *filemap_grab_folio(struct address_space *mapping, | |
804 | pgoff_t index) | |
805 | { | |
806 | return __filemap_get_folio(mapping, index, | |
807 | FGP_LOCK | FGP_ACCESSED | FGP_CREAT, | |
808 | mapping_gfp_mask(mapping)); | |
809 | } | |
810 | ||
2457aec6 MG |
811 | /** |
812 | * find_get_page - find and get a page reference | |
813 | * @mapping: the address_space to search | |
814 | * @offset: the page index | |
815 | * | |
816 | * Looks up the page cache slot at @mapping & @offset. If there is a | |
817 | * page cache page, it is returned with an increased refcount. | |
818 | * | |
819 | * Otherwise, %NULL is returned. | |
820 | */ | |
821 | static inline struct page *find_get_page(struct address_space *mapping, | |
822 | pgoff_t offset) | |
823 | { | |
45f87de5 | 824 | return pagecache_get_page(mapping, offset, 0, 0); |
2457aec6 MG |
825 | } |
826 | ||
827 | static inline struct page *find_get_page_flags(struct address_space *mapping, | |
ffc143db | 828 | pgoff_t offset, fgf_t fgp_flags) |
2457aec6 | 829 | { |
45f87de5 | 830 | return pagecache_get_page(mapping, offset, fgp_flags, 0); |
2457aec6 MG |
831 | } |
832 | ||
833 | /** | |
834 | * find_lock_page - locate, pin and lock a pagecache page | |
2457aec6 | 835 | * @mapping: the address_space to search |
89b42235 | 836 | * @index: the page index |
2457aec6 | 837 | * |
89b42235 | 838 | * Looks up the page cache entry at @mapping & @index. If there is a |
2457aec6 MG |
839 | * page cache page, it is returned locked and with an increased |
840 | * refcount. | |
841 | * | |
a8cf7f27 MWO |
842 | * Context: May sleep. |
843 | * Return: A struct page or %NULL if there is no page in the cache for this | |
844 | * index. | |
2457aec6 MG |
845 | */ |
846 | static inline struct page *find_lock_page(struct address_space *mapping, | |
a8cf7f27 MWO |
847 | pgoff_t index) |
848 | { | |
849 | return pagecache_get_page(mapping, index, FGP_LOCK, 0); | |
850 | } | |
851 | ||
2457aec6 MG |
852 | /** |
853 | * find_or_create_page - locate or add a pagecache page | |
854 | * @mapping: the page's address_space | |
855 | * @index: the page's index into the mapping | |
856 | * @gfp_mask: page allocation mode | |
857 | * | |
858 | * Looks up the page cache slot at @mapping & @offset. If there is a | |
859 | * page cache page, it is returned locked and with an increased | |
860 | * refcount. | |
861 | * | |
862 | * If the page is not present, a new page is allocated using @gfp_mask | |
863 | * and added to the page cache and the VM's LRU list. The page is | |
864 | * returned locked and with an increased refcount. | |
865 | * | |
866 | * On memory exhaustion, %NULL is returned. | |
867 | * | |
868 | * find_or_create_page() may sleep, even if @gfp_flags specifies an | |
869 | * atomic allocation! | |
870 | */ | |
871 | static inline struct page *find_or_create_page(struct address_space *mapping, | |
767e5ee5 | 872 | pgoff_t index, gfp_t gfp_mask) |
2457aec6 | 873 | { |
767e5ee5 | 874 | return pagecache_get_page(mapping, index, |
2457aec6 | 875 | FGP_LOCK|FGP_ACCESSED|FGP_CREAT, |
45f87de5 | 876 | gfp_mask); |
2457aec6 MG |
877 | } |
878 | ||
879 | /** | |
880 | * grab_cache_page_nowait - returns locked page at given index in given cache | |
881 | * @mapping: target address_space | |
882 | * @index: the page index | |
883 | * | |
884 | * Same as grab_cache_page(), but do not wait if the page is unavailable. | |
885 | * This is intended for speculative data generators, where the data can | |
886 | * be regenerated if the page couldn't be grabbed. This routine should | |
887 | * be safe to call while holding the lock for another page. | |
888 | * | |
889 | * Clear __GFP_FS when allocating the page to avoid recursion into the fs | |
890 | * and deadlock against the caller's locked page. | |
891 | */ | |
892 | static inline struct page *grab_cache_page_nowait(struct address_space *mapping, | |
893 | pgoff_t index) | |
894 | { | |
895 | return pagecache_get_page(mapping, index, | |
896 | FGP_LOCK|FGP_CREAT|FGP_NOFS|FGP_NOWAIT, | |
45f87de5 | 897 | mapping_gfp_mask(mapping)); |
2457aec6 MG |
898 | } |
899 | ||
05b0c7ed | 900 | extern pgoff_t __folio_swap_cache_index(struct folio *folio); |
9257e156 MWO |
901 | |
902 | /** | |
903 | * folio_index - File index of a folio. | |
904 | * @folio: The folio. | |
905 | * | |
906 | * For a folio which is either in the page cache or the swap cache, | |
907 | * return its index within the address_space it belongs to. If you know | |
908 | * the page is definitely in the page cache, you can look at the folio's | |
909 | * index directly. | |
910 | * | |
911 | * Return: The index (offset in units of pages) of a folio in its file. | |
912 | */ | |
913 | static inline pgoff_t folio_index(struct folio *folio) | |
914 | { | |
05b0c7ed KS |
915 | if (unlikely(folio_test_swapcache(folio))) |
916 | return __folio_swap_cache_index(folio); | |
917 | return folio->index; | |
9257e156 MWO |
918 | } |
919 | ||
f94b18f6 MWO |
920 | /** |
921 | * folio_next_index - Get the index of the next folio. | |
922 | * @folio: The current folio. | |
923 | * | |
924 | * Return: The index of the folio which follows this folio in the file. | |
925 | */ | |
926 | static inline pgoff_t folio_next_index(struct folio *folio) | |
927 | { | |
928 | return folio->index + folio_nr_pages(folio); | |
929 | } | |
930 | ||
9257e156 MWO |
931 | /** |
932 | * folio_file_page - The page for a particular index. | |
933 | * @folio: The folio which contains this index. | |
934 | * @index: The index we want to look up. | |
935 | * | |
936 | * Sometimes after looking up a folio in the page cache, we need to | |
937 | * obtain the specific page for an index (eg a page fault). | |
938 | * | |
939 | * Return: The page containing the file data for this index. | |
940 | */ | |
941 | static inline struct page *folio_file_page(struct folio *folio, pgoff_t index) | |
942 | { | |
9257e156 MWO |
943 | return folio_page(folio, index & (folio_nr_pages(folio) - 1)); |
944 | } | |
945 | ||
946 | /** | |
947 | * folio_contains - Does this folio contain this index? | |
948 | * @folio: The folio. | |
949 | * @index: The page index within the file. | |
950 | * | |
951 | * Context: The caller should have the page locked in order to prevent | |
952 | * (eg) shmem from moving the page between the page cache and swap cache | |
953 | * and changing its index in the middle of the operation. | |
954 | * Return: true or false. | |
955 | */ | |
956 | static inline bool folio_contains(struct folio *folio, pgoff_t index) | |
957 | { | |
9257e156 MWO |
958 | return index - folio_index(folio) < folio_nr_pages(folio); |
959 | } | |
960 | ||
ec848215 MWO |
961 | /* |
962 | * Given the page we found in the page cache, return the page corresponding | |
963 | * to this index in the file | |
964 | */ | |
965 | static inline struct page *find_subpage(struct page *head, pgoff_t index) | |
4101196b | 966 | { |
ec848215 MWO |
967 | /* HugeTLBfs wants the head page regardless */ |
968 | if (PageHuge(head)) | |
969 | return head; | |
4101196b | 970 | |
6c357848 | 971 | return head + (index & (thp_nr_pages(head) - 1)); |
4101196b MWO |
972 | } |
973 | ||
be0ced5e MWO |
974 | unsigned filemap_get_folios(struct address_space *mapping, pgoff_t *start, |
975 | pgoff_t end, struct folio_batch *fbatch); | |
35b47146 VMO |
976 | unsigned filemap_get_folios_contig(struct address_space *mapping, |
977 | pgoff_t *start, pgoff_t end, struct folio_batch *fbatch); | |
247f9e1f VMO |
978 | unsigned filemap_get_folios_tag(struct address_space *mapping, pgoff_t *start, |
979 | pgoff_t end, xa_mark_t tag, struct folio_batch *fbatch); | |
1da177e4 | 980 | |
54566b2c | 981 | struct page *grab_cache_page_write_begin(struct address_space *mapping, |
b7446e7c | 982 | pgoff_t index); |
afddba49 | 983 | |
1da177e4 LT |
984 | /* |
985 | * Returns locked page at given index in given cache, creating it if needed. | |
986 | */ | |
57f6b96c FW |
987 | static inline struct page *grab_cache_page(struct address_space *mapping, |
988 | pgoff_t index) | |
1da177e4 LT |
989 | { |
990 | return find_or_create_page(mapping, index, mapping_gfp_mask(mapping)); | |
991 | } | |
992 | ||
539a3322 | 993 | struct folio *read_cache_folio(struct address_space *, pgoff_t index, |
e9b5b23e | 994 | filler_t *filler, struct file *file); |
3e629597 MWO |
995 | struct folio *mapping_read_folio_gfp(struct address_space *, pgoff_t index, |
996 | gfp_t flags); | |
539a3322 | 997 | struct page *read_cache_page(struct address_space *, pgoff_t index, |
e9b5b23e | 998 | filler_t *filler, struct file *file); |
0531b2aa LT |
999 | extern struct page * read_cache_page_gfp(struct address_space *mapping, |
1000 | pgoff_t index, gfp_t gfp_mask); | |
1da177e4 | 1001 | |
090d2b18 | 1002 | static inline struct page *read_mapping_page(struct address_space *mapping, |
c14c6843 | 1003 | pgoff_t index, struct file *file) |
090d2b18 | 1004 | { |
c14c6843 | 1005 | return read_cache_page(mapping, index, NULL, file); |
090d2b18 PE |
1006 | } |
1007 | ||
539a3322 | 1008 | static inline struct folio *read_mapping_folio(struct address_space *mapping, |
c14c6843 | 1009 | pgoff_t index, struct file *file) |
539a3322 | 1010 | { |
c14c6843 | 1011 | return read_cache_folio(mapping, index, NULL, file); |
539a3322 MWO |
1012 | } |
1013 | ||
a0f7a756 | 1014 | /* |
a08c7193 | 1015 | * Get the offset in PAGE_SIZE (even for hugetlb pages). |
a0f7a756 | 1016 | */ |
a08c7193 | 1017 | static inline pgoff_t page_to_pgoff(struct page *page) |
a0f7a756 | 1018 | { |
fe3df441 | 1019 | struct page *head; |
e9b61f19 | 1020 | |
e9b61f19 | 1021 | if (likely(!PageTransTail(page))) |
09cbfeaf | 1022 | return page->index; |
e9b61f19 | 1023 | |
fe3df441 | 1024 | head = compound_head(page); |
e9b61f19 KS |
1025 | /* |
1026 | * We don't initialize ->index for tail pages: calculate based on | |
1027 | * head page | |
1028 | */ | |
fe3df441 | 1029 | return head->index + page - head; |
a0f7a756 NH |
1030 | } |
1031 | ||
1da177e4 LT |
1032 | /* |
1033 | * Return byte-offset into filesystem object for page. | |
1034 | */ | |
1035 | static inline loff_t page_offset(struct page *page) | |
1036 | { | |
09cbfeaf | 1037 | return ((loff_t)page->index) << PAGE_SHIFT; |
1da177e4 LT |
1038 | } |
1039 | ||
352b47a6 MWO |
1040 | /** |
1041 | * folio_pos - Returns the byte position of this folio in its file. | |
1042 | * @folio: The folio. | |
1043 | */ | |
1044 | static inline loff_t folio_pos(struct folio *folio) | |
1045 | { | |
1046 | return page_offset(&folio->page); | |
1047 | } | |
1048 | ||
f087b903 MWO |
1049 | /* |
1050 | * Get the offset in PAGE_SIZE (even for hugetlb folios). | |
f087b903 MWO |
1051 | */ |
1052 | static inline pgoff_t folio_pgoff(struct folio *folio) | |
1053 | { | |
f087b903 MWO |
1054 | return folio->index; |
1055 | } | |
1056 | ||
1da177e4 LT |
1057 | static inline pgoff_t linear_page_index(struct vm_area_struct *vma, |
1058 | unsigned long address) | |
1059 | { | |
0fe6e20b | 1060 | pgoff_t pgoff; |
0fe6e20b | 1061 | pgoff = (address - vma->vm_start) >> PAGE_SHIFT; |
1da177e4 | 1062 | pgoff += vma->vm_pgoff; |
09cbfeaf | 1063 | return pgoff; |
1da177e4 LT |
1064 | } |
1065 | ||
c7510ab2 | 1066 | struct wait_page_key { |
df4d4f12 | 1067 | struct folio *folio; |
c7510ab2 JA |
1068 | int bit_nr; |
1069 | int page_match; | |
1070 | }; | |
1071 | ||
1072 | struct wait_page_queue { | |
df4d4f12 | 1073 | struct folio *folio; |
c7510ab2 JA |
1074 | int bit_nr; |
1075 | wait_queue_entry_t wait; | |
1076 | }; | |
1077 | ||
cdc8fcb4 | 1078 | static inline bool wake_page_match(struct wait_page_queue *wait_page, |
c7510ab2 JA |
1079 | struct wait_page_key *key) |
1080 | { | |
df4d4f12 | 1081 | if (wait_page->folio != key->folio) |
cdc8fcb4 | 1082 | return false; |
c7510ab2 JA |
1083 | key->page_match = 1; |
1084 | ||
1085 | if (wait_page->bit_nr != key->bit_nr) | |
cdc8fcb4 | 1086 | return false; |
d1932dc3 | 1087 | |
cdc8fcb4 | 1088 | return true; |
d1932dc3 JA |
1089 | } |
1090 | ||
7c23c782 | 1091 | void __folio_lock(struct folio *folio); |
af7f29d9 | 1092 | int __folio_lock_killable(struct folio *folio); |
fdc724d6 | 1093 | vm_fault_t __folio_lock_or_retry(struct folio *folio, struct vm_fault *vmf); |
4e136428 MWO |
1094 | void unlock_page(struct page *page); |
1095 | void folio_unlock(struct folio *folio); | |
1da177e4 | 1096 | |
cd125eea MWO |
1097 | /** |
1098 | * folio_trylock() - Attempt to lock a folio. | |
1099 | * @folio: The folio to attempt to lock. | |
1100 | * | |
1101 | * Sometimes it is undesirable to wait for a folio to be unlocked (eg | |
1102 | * when the locks are being taken in the wrong order, or if making | |
1103 | * progress through a batch of folios is more important than processing | |
1104 | * them in order). Usually folio_lock() is the correct function to call. | |
1105 | * | |
1106 | * Context: Any context. | |
1107 | * Return: Whether the lock was successfully acquired. | |
1108 | */ | |
7c23c782 MWO |
1109 | static inline bool folio_trylock(struct folio *folio) |
1110 | { | |
1111 | return likely(!test_and_set_bit_lock(PG_locked, folio_flags(folio, 0))); | |
1112 | } | |
1113 | ||
f4458845 AM |
1114 | /* |
1115 | * Return true if the page was successfully locked | |
1116 | */ | |
62087556 | 1117 | static inline bool trylock_page(struct page *page) |
529ae9aa | 1118 | { |
7c23c782 MWO |
1119 | return folio_trylock(page_folio(page)); |
1120 | } | |
1121 | ||
cd125eea MWO |
1122 | /** |
1123 | * folio_lock() - Lock this folio. | |
1124 | * @folio: The folio to lock. | |
1125 | * | |
1126 | * The folio lock protects against many things, probably more than it | |
1127 | * should. It is primarily held while a folio is being brought uptodate, | |
1128 | * either from its backing file or from swap. It is also held while a | |
1129 | * folio is being truncated from its address_space, so holding the lock | |
1130 | * is sufficient to keep folio->mapping stable. | |
1131 | * | |
1132 | * The folio lock is also held while write() is modifying the page to | |
1133 | * provide POSIX atomicity guarantees (as long as the write does not | |
1134 | * cross a page boundary). Other modifications to the data in the folio | |
1135 | * do not hold the folio lock and can race with writes, eg DMA and stores | |
1136 | * to mapped pages. | |
1137 | * | |
1138 | * Context: May sleep. If you need to acquire the locks of two or | |
1139 | * more folios, they must be in order of ascending index, if they are | |
1140 | * in the same address_space. If they are in different address_spaces, | |
1141 | * acquire the lock of the folio which belongs to the address_space which | |
1142 | * has the lowest address in memory first. | |
1143 | */ | |
7c23c782 MWO |
1144 | static inline void folio_lock(struct folio *folio) |
1145 | { | |
1146 | might_sleep(); | |
1147 | if (!folio_trylock(folio)) | |
1148 | __folio_lock(folio); | |
529ae9aa NP |
1149 | } |
1150 | ||
cd125eea MWO |
1151 | /** |
1152 | * lock_page() - Lock the folio containing this page. | |
1153 | * @page: The page to lock. | |
1154 | * | |
1155 | * See folio_lock() for a description of what the lock protects. | |
1156 | * This is a legacy function and new code should probably use folio_lock() | |
1157 | * instead. | |
1158 | * | |
1159 | * Context: May sleep. Pages in the same folio share a lock, so do not | |
1160 | * attempt to lock two pages which share a folio. | |
db37648c | 1161 | */ |
1da177e4 LT |
1162 | static inline void lock_page(struct page *page) |
1163 | { | |
7c23c782 | 1164 | struct folio *folio; |
1da177e4 | 1165 | might_sleep(); |
7c23c782 MWO |
1166 | |
1167 | folio = page_folio(page); | |
1168 | if (!folio_trylock(folio)) | |
1169 | __folio_lock(folio); | |
1da177e4 | 1170 | } |
db37648c | 1171 | |
cd125eea MWO |
1172 | /** |
1173 | * folio_lock_killable() - Lock this folio, interruptible by a fatal signal. | |
1174 | * @folio: The folio to lock. | |
1175 | * | |
1176 | * Attempts to lock the folio, like folio_lock(), except that the sleep | |
1177 | * to acquire the lock is interruptible by a fatal signal. | |
1178 | * | |
1179 | * Context: May sleep; see folio_lock(). | |
1180 | * Return: 0 if the lock was acquired; -EINTR if a fatal signal was received. | |
1181 | */ | |
af7f29d9 MWO |
1182 | static inline int folio_lock_killable(struct folio *folio) |
1183 | { | |
1184 | might_sleep(); | |
1185 | if (!folio_trylock(folio)) | |
1186 | return __folio_lock_killable(folio); | |
1187 | return 0; | |
1188 | } | |
1189 | ||
d065bd81 | 1190 | /* |
19672a9e | 1191 | * folio_lock_or_retry - Lock the folio, unless this would block and the |
d065bd81 | 1192 | * caller indicated that it can handle a retry. |
9a95f3cf | 1193 | * |
c1e8d7c6 | 1194 | * Return value and mmap_lock implications depend on flags; see |
9138e47e | 1195 | * __folio_lock_or_retry(). |
d065bd81 | 1196 | */ |
fdc724d6 SB |
1197 | static inline vm_fault_t folio_lock_or_retry(struct folio *folio, |
1198 | struct vm_fault *vmf) | |
d065bd81 ML |
1199 | { |
1200 | might_sleep(); | |
fdc724d6 SB |
1201 | if (!folio_trylock(folio)) |
1202 | return __folio_lock_or_retry(folio, vmf); | |
1203 | return 0; | |
d065bd81 ML |
1204 | } |
1205 | ||
1da177e4 | 1206 | /* |
101c0bf6 | 1207 | * This is exported only for folio_wait_locked/folio_wait_writeback, etc., |
74d81bfa | 1208 | * and should not be used directly. |
1da177e4 | 1209 | */ |
101c0bf6 MWO |
1210 | void folio_wait_bit(struct folio *folio, int bit_nr); |
1211 | int folio_wait_bit_killable(struct folio *folio, int bit_nr); | |
a4796e37 | 1212 | |
1da177e4 | 1213 | /* |
6baa8d60 | 1214 | * Wait for a folio to be unlocked. |
1da177e4 | 1215 | * |
6baa8d60 | 1216 | * This must be called with the caller "holding" the folio, |
cd125eea MWO |
1217 | * ie with increased folio reference count so that the folio won't |
1218 | * go away during the wait. | |
1da177e4 | 1219 | */ |
6baa8d60 MWO |
1220 | static inline void folio_wait_locked(struct folio *folio) |
1221 | { | |
1222 | if (folio_test_locked(folio)) | |
101c0bf6 | 1223 | folio_wait_bit(folio, PG_locked); |
6baa8d60 MWO |
1224 | } |
1225 | ||
1226 | static inline int folio_wait_locked_killable(struct folio *folio) | |
1227 | { | |
1228 | if (!folio_test_locked(folio)) | |
1229 | return 0; | |
101c0bf6 | 1230 | return folio_wait_bit_killable(folio, PG_locked); |
6baa8d60 MWO |
1231 | } |
1232 | ||
1da177e4 LT |
1233 | static inline void wait_on_page_locked(struct page *page) |
1234 | { | |
6baa8d60 | 1235 | folio_wait_locked(page_folio(page)); |
1da177e4 LT |
1236 | } |
1237 | ||
0b237047 | 1238 | void folio_end_read(struct folio *folio, bool success); |
19343b5b | 1239 | void wait_on_page_writeback(struct page *page); |
490e016f MWO |
1240 | void folio_wait_writeback(struct folio *folio); |
1241 | int folio_wait_writeback_killable(struct folio *folio); | |
4268b480 MWO |
1242 | void end_page_writeback(struct page *page); |
1243 | void folio_end_writeback(struct folio *folio); | |
1d1d1a76 | 1244 | void wait_for_stable_page(struct page *page); |
a49d0c50 | 1245 | void folio_wait_stable(struct folio *folio); |
203a3151 | 1246 | void __folio_mark_dirty(struct folio *folio, struct address_space *, int warn); |
566d3362 | 1247 | void folio_account_cleaned(struct folio *folio, struct bdi_writeback *wb); |
fdaf532a MWO |
1248 | void __folio_cancel_dirty(struct folio *folio); |
1249 | static inline void folio_cancel_dirty(struct folio *folio) | |
1250 | { | |
1251 | /* Avoid atomic ops, locking, etc. when not actually needed. */ | |
1252 | if (folio_test_dirty(folio)) | |
1253 | __folio_cancel_dirty(folio); | |
1254 | } | |
9350f20a MWO |
1255 | bool folio_clear_dirty_for_io(struct folio *folio); |
1256 | bool clear_page_dirty_for_io(struct page *page); | |
5ad6b2bd | 1257 | void folio_invalidate(struct folio *folio, size_t offset, size_t length); |
46de8b97 | 1258 | bool noop_dirty_folio(struct address_space *mapping, struct folio *folio); |
3a6b2162 | 1259 | |
2ec810d5 MWO |
1260 | #ifdef CONFIG_MIGRATION |
1261 | int filemap_migrate_folio(struct address_space *mapping, struct folio *dst, | |
1262 | struct folio *src, enum migrate_mode mode); | |
1263 | #else | |
1264 | #define filemap_migrate_folio NULL | |
1265 | #endif | |
b47393f8 MWO |
1266 | void folio_end_private_2(struct folio *folio); |
1267 | void folio_wait_private_2(struct folio *folio); | |
1268 | int folio_wait_private_2_killable(struct folio *folio); | |
73e10ded | 1269 | |
385e1ca5 DH |
1270 | /* |
1271 | * Add an arbitrary waiter to a page's wait queue | |
1272 | */ | |
df4d4f12 | 1273 | void folio_add_wait_queue(struct folio *folio, wait_queue_entry_t *waiter); |
385e1ca5 | 1274 | |
1da177e4 | 1275 | /* |
bb523b40 | 1276 | * Fault in userspace address range. |
1da177e4 | 1277 | */ |
bb523b40 | 1278 | size_t fault_in_writeable(char __user *uaddr, size_t size); |
da32b581 | 1279 | size_t fault_in_subpage_writeable(char __user *uaddr, size_t size); |
cdd591fc | 1280 | size_t fault_in_safe_writeable(const char __user *uaddr, size_t size); |
bb523b40 | 1281 | size_t fault_in_readable(const char __user *uaddr, size_t size); |
f56f821f | 1282 | |
529ae9aa | 1283 | int add_to_page_cache_lru(struct page *page, struct address_space *mapping, |
9dd3d069 MWO |
1284 | pgoff_t index, gfp_t gfp); |
1285 | int filemap_add_folio(struct address_space *mapping, struct folio *folio, | |
1286 | pgoff_t index, gfp_t gfp); | |
452e9e69 | 1287 | void filemap_remove_folio(struct folio *folio); |
452e9e69 | 1288 | void __filemap_remove_folio(struct folio *folio, void *shadow); |
3720dd6d | 1289 | void replace_page_cache_folio(struct folio *old, struct folio *new); |
aa65c29c | 1290 | void delete_from_page_cache_batch(struct address_space *mapping, |
51dcbdac | 1291 | struct folio_batch *fbatch); |
82c50f8b | 1292 | bool filemap_release_folio(struct folio *folio, gfp_t gfp); |
41139aa4 MWO |
1293 | loff_t mapping_seek_hole_data(struct address_space *, loff_t start, loff_t end, |
1294 | int whence); | |
529ae9aa | 1295 | |
9dd3d069 MWO |
1296 | /* Must be non-static for BPF error injection */ |
1297 | int __filemap_add_folio(struct address_space *mapping, struct folio *folio, | |
1298 | pgoff_t index, gfp_t gfp, void **shadowp); | |
1299 | ||
4bdcd1dd JA |
1300 | bool filemap_range_has_writeback(struct address_space *mapping, |
1301 | loff_t start_byte, loff_t end_byte); | |
1302 | ||
1303 | /** | |
1304 | * filemap_range_needs_writeback - check if range potentially needs writeback | |
1305 | * @mapping: address space within which to check | |
1306 | * @start_byte: offset in bytes where the range starts | |
1307 | * @end_byte: offset in bytes where the range ends (inclusive) | |
1308 | * | |
1309 | * Find at least one page in the range supplied, usually used to check if | |
1310 | * direct writing in this range will trigger a writeback. Used by O_DIRECT | |
1311 | * read/write with IOCB_NOWAIT, to see if the caller needs to do | |
1312 | * filemap_write_and_wait_range() before proceeding. | |
1313 | * | |
1314 | * Return: %true if the caller should do filemap_write_and_wait_range() before | |
1315 | * doing O_DIRECT to a page in this range, %false otherwise. | |
1316 | */ | |
1317 | static inline bool filemap_range_needs_writeback(struct address_space *mapping, | |
1318 | loff_t start_byte, | |
1319 | loff_t end_byte) | |
1320 | { | |
1321 | if (!mapping->nrpages) | |
1322 | return false; | |
1323 | if (!mapping_tagged(mapping, PAGECACHE_TAG_DIRTY) && | |
1324 | !mapping_tagged(mapping, PAGECACHE_TAG_WRITEBACK)) | |
1325 | return false; | |
1326 | return filemap_range_has_writeback(mapping, start_byte, end_byte); | |
1327 | } | |
1328 | ||
042124cc MWO |
1329 | /** |
1330 | * struct readahead_control - Describes a readahead request. | |
1331 | * | |
1332 | * A readahead request is for consecutive pages. Filesystems which | |
1333 | * implement the ->readahead method should call readahead_page() or | |
1334 | * readahead_page_batch() in a loop and attempt to start I/O against | |
1335 | * each page in the request. | |
1336 | * | |
1337 | * Most of the fields in this struct are private and should be accessed | |
1338 | * by the functions below. | |
1339 | * | |
1340 | * @file: The file, used primarily by network filesystems for authentication. | |
1341 | * May be NULL if invoked internally by the filesystem. | |
1342 | * @mapping: Readahead this filesystem object. | |
fcd9ae4f | 1343 | * @ra: File readahead state. May be NULL. |
042124cc MWO |
1344 | */ |
1345 | struct readahead_control { | |
1346 | struct file *file; | |
1347 | struct address_space *mapping; | |
fcd9ae4f | 1348 | struct file_ra_state *ra; |
042124cc MWO |
1349 | /* private: use the readahead_* accessors instead */ |
1350 | pgoff_t _index; | |
1351 | unsigned int _nr_pages; | |
1352 | unsigned int _batch_count; | |
17604240 CH |
1353 | bool _workingset; |
1354 | unsigned long _pflags; | |
042124cc MWO |
1355 | }; |
1356 | ||
fcd9ae4f MWO |
1357 | #define DEFINE_READAHEAD(ractl, f, r, m, i) \ |
1358 | struct readahead_control ractl = { \ | |
1aa83cfa MWO |
1359 | .file = f, \ |
1360 | .mapping = m, \ | |
fcd9ae4f | 1361 | .ra = r, \ |
1aa83cfa MWO |
1362 | ._index = i, \ |
1363 | } | |
1364 | ||
fefa7c47 MWO |
1365 | #define VM_READAHEAD_PAGES (SZ_128K / PAGE_SIZE) |
1366 | ||
1367 | void page_cache_ra_unbounded(struct readahead_control *, | |
1368 | unsigned long nr_to_read, unsigned long lookahead_count); | |
fcd9ae4f | 1369 | void page_cache_sync_ra(struct readahead_control *, unsigned long req_count); |
7836d999 | 1370 | void page_cache_async_ra(struct readahead_control *, struct folio *, |
fefa7c47 | 1371 | unsigned long req_count); |
3ca23644 DH |
1372 | void readahead_expand(struct readahead_control *ractl, |
1373 | loff_t new_start, size_t new_len); | |
fefa7c47 MWO |
1374 | |
1375 | /** | |
1376 | * page_cache_sync_readahead - generic file readahead | |
1377 | * @mapping: address_space which holds the pagecache and I/O vectors | |
1378 | * @ra: file_ra_state which holds the readahead state | |
1379 | * @file: Used by the filesystem for authentication. | |
1380 | * @index: Index of first page to be read. | |
1381 | * @req_count: Total number of pages being read by the caller. | |
1382 | * | |
1383 | * page_cache_sync_readahead() should be called when a cache miss happened: | |
1384 | * it will submit the read. The readahead logic may decide to piggyback more | |
1385 | * pages onto the read request if access patterns suggest it will improve | |
1386 | * performance. | |
1387 | */ | |
1388 | static inline | |
1389 | void page_cache_sync_readahead(struct address_space *mapping, | |
1390 | struct file_ra_state *ra, struct file *file, pgoff_t index, | |
1391 | unsigned long req_count) | |
1392 | { | |
fcd9ae4f MWO |
1393 | DEFINE_READAHEAD(ractl, file, ra, mapping, index); |
1394 | page_cache_sync_ra(&ractl, req_count); | |
fefa7c47 MWO |
1395 | } |
1396 | ||
1397 | /** | |
1398 | * page_cache_async_readahead - file readahead for marked pages | |
1399 | * @mapping: address_space which holds the pagecache and I/O vectors | |
1400 | * @ra: file_ra_state which holds the readahead state | |
1401 | * @file: Used by the filesystem for authentication. | |
bb82ac31 | 1402 | * @folio: The folio which triggered the readahead call. |
fefa7c47 MWO |
1403 | * @req_count: Total number of pages being read by the caller. |
1404 | * | |
1405 | * page_cache_async_readahead() should be called when a page is used which | |
1406 | * is marked as PageReadahead; this is a marker to suggest that the application | |
1407 | * has used up enough of the readahead window that we should start pulling in | |
1408 | * more pages. | |
1409 | */ | |
1410 | static inline | |
1411 | void page_cache_async_readahead(struct address_space *mapping, | |
1412 | struct file_ra_state *ra, struct file *file, | |
bb82ac31 | 1413 | struct folio *folio, unsigned long req_count) |
fefa7c47 | 1414 | { |
bb82ac31 | 1415 | DEFINE_READAHEAD(ractl, file, ra, mapping, folio->index); |
2ebdd1df | 1416 | page_cache_async_ra(&ractl, folio, req_count); |
fefa7c47 MWO |
1417 | } |
1418 | ||
9bf70167 MWO |
1419 | static inline struct folio *__readahead_folio(struct readahead_control *ractl) |
1420 | { | |
1421 | struct folio *folio; | |
1422 | ||
1423 | BUG_ON(ractl->_batch_count > ractl->_nr_pages); | |
1424 | ractl->_nr_pages -= ractl->_batch_count; | |
1425 | ractl->_index += ractl->_batch_count; | |
1426 | ||
1427 | if (!ractl->_nr_pages) { | |
1428 | ractl->_batch_count = 0; | |
1429 | return NULL; | |
1430 | } | |
1431 | ||
1432 | folio = xa_load(&ractl->mapping->i_pages, ractl->_index); | |
1433 | VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio); | |
1434 | ractl->_batch_count = folio_nr_pages(folio); | |
1435 | ||
1436 | return folio; | |
1437 | } | |
1438 | ||
042124cc MWO |
1439 | /** |
1440 | * readahead_page - Get the next page to read. | |
9bf70167 | 1441 | * @ractl: The current readahead request. |
042124cc MWO |
1442 | * |
1443 | * Context: The page is locked and has an elevated refcount. The caller | |
1444 | * should decreases the refcount once the page has been submitted for I/O | |
1445 | * and unlock the page once all I/O to that page has completed. | |
1446 | * Return: A pointer to the next page, or %NULL if we are done. | |
1447 | */ | |
9bf70167 | 1448 | static inline struct page *readahead_page(struct readahead_control *ractl) |
042124cc | 1449 | { |
9bf70167 | 1450 | struct folio *folio = __readahead_folio(ractl); |
042124cc | 1451 | |
9bf70167 MWO |
1452 | return &folio->page; |
1453 | } | |
042124cc | 1454 | |
9bf70167 MWO |
1455 | /** |
1456 | * readahead_folio - Get the next folio to read. | |
1457 | * @ractl: The current readahead request. | |
1458 | * | |
1459 | * Context: The folio is locked. The caller should unlock the folio once | |
1460 | * all I/O to that folio has completed. | |
1461 | * Return: A pointer to the next folio, or %NULL if we are done. | |
1462 | */ | |
1463 | static inline struct folio *readahead_folio(struct readahead_control *ractl) | |
1464 | { | |
1465 | struct folio *folio = __readahead_folio(ractl); | |
042124cc | 1466 | |
9bf70167 MWO |
1467 | if (folio) |
1468 | folio_put(folio); | |
1469 | return folio; | |
042124cc MWO |
1470 | } |
1471 | ||
1472 | static inline unsigned int __readahead_batch(struct readahead_control *rac, | |
1473 | struct page **array, unsigned int array_sz) | |
1474 | { | |
1475 | unsigned int i = 0; | |
1476 | XA_STATE(xas, &rac->mapping->i_pages, 0); | |
1477 | struct page *page; | |
1478 | ||
1479 | BUG_ON(rac->_batch_count > rac->_nr_pages); | |
1480 | rac->_nr_pages -= rac->_batch_count; | |
1481 | rac->_index += rac->_batch_count; | |
1482 | rac->_batch_count = 0; | |
1483 | ||
1484 | xas_set(&xas, rac->_index); | |
1485 | rcu_read_lock(); | |
1486 | xas_for_each(&xas, page, rac->_index + rac->_nr_pages - 1) { | |
4349a83a MWO |
1487 | if (xas_retry(&xas, page)) |
1488 | continue; | |
042124cc MWO |
1489 | VM_BUG_ON_PAGE(!PageLocked(page), page); |
1490 | VM_BUG_ON_PAGE(PageTail(page), page); | |
1491 | array[i++] = page; | |
6c357848 | 1492 | rac->_batch_count += thp_nr_pages(page); |
042124cc MWO |
1493 | if (i == array_sz) |
1494 | break; | |
1495 | } | |
1496 | rcu_read_unlock(); | |
1497 | ||
1498 | return i; | |
1499 | } | |
1500 | ||
1501 | /** | |
1502 | * readahead_page_batch - Get a batch of pages to read. | |
1503 | * @rac: The current readahead request. | |
1504 | * @array: An array of pointers to struct page. | |
1505 | * | |
1506 | * Context: The pages are locked and have an elevated refcount. The caller | |
1507 | * should decreases the refcount once the page has been submitted for I/O | |
1508 | * and unlock the page once all I/O to that page has completed. | |
1509 | * Return: The number of pages placed in the array. 0 indicates the request | |
1510 | * is complete. | |
1511 | */ | |
1512 | #define readahead_page_batch(rac, array) \ | |
1513 | __readahead_batch(rac, array, ARRAY_SIZE(array)) | |
1514 | ||
1515 | /** | |
1516 | * readahead_pos - The byte offset into the file of this readahead request. | |
1517 | * @rac: The readahead request. | |
1518 | */ | |
1519 | static inline loff_t readahead_pos(struct readahead_control *rac) | |
1520 | { | |
1521 | return (loff_t)rac->_index * PAGE_SIZE; | |
1522 | } | |
1523 | ||
1524 | /** | |
1525 | * readahead_length - The number of bytes in this readahead request. | |
1526 | * @rac: The readahead request. | |
1527 | */ | |
076171a6 | 1528 | static inline size_t readahead_length(struct readahead_control *rac) |
042124cc | 1529 | { |
076171a6 | 1530 | return rac->_nr_pages * PAGE_SIZE; |
042124cc MWO |
1531 | } |
1532 | ||
1533 | /** | |
1534 | * readahead_index - The index of the first page in this readahead request. | |
1535 | * @rac: The readahead request. | |
1536 | */ | |
1537 | static inline pgoff_t readahead_index(struct readahead_control *rac) | |
1538 | { | |
1539 | return rac->_index; | |
1540 | } | |
1541 | ||
1542 | /** | |
1543 | * readahead_count - The number of pages in this readahead request. | |
1544 | * @rac: The readahead request. | |
1545 | */ | |
1546 | static inline unsigned int readahead_count(struct readahead_control *rac) | |
1547 | { | |
1548 | return rac->_nr_pages; | |
1549 | } | |
1550 | ||
32c0a6bc MWO |
1551 | /** |
1552 | * readahead_batch_length - The number of bytes in the current batch. | |
1553 | * @rac: The readahead request. | |
1554 | */ | |
076171a6 | 1555 | static inline size_t readahead_batch_length(struct readahead_control *rac) |
32c0a6bc MWO |
1556 | { |
1557 | return rac->_batch_count * PAGE_SIZE; | |
1558 | } | |
1559 | ||
b57c2cb9 FF |
1560 | static inline unsigned long dir_pages(struct inode *inode) |
1561 | { | |
09cbfeaf KS |
1562 | return (unsigned long)(inode->i_size + PAGE_SIZE - 1) >> |
1563 | PAGE_SHIFT; | |
b57c2cb9 FF |
1564 | } |
1565 | ||
f705bf84 MWO |
1566 | /** |
1567 | * folio_mkwrite_check_truncate - check if folio was truncated | |
1568 | * @folio: the folio to check | |
1569 | * @inode: the inode to check the folio against | |
1570 | * | |
1571 | * Return: the number of bytes in the folio up to EOF, | |
1572 | * or -EFAULT if the folio was truncated. | |
1573 | */ | |
1574 | static inline ssize_t folio_mkwrite_check_truncate(struct folio *folio, | |
1575 | struct inode *inode) | |
1576 | { | |
1577 | loff_t size = i_size_read(inode); | |
1578 | pgoff_t index = size >> PAGE_SHIFT; | |
1579 | size_t offset = offset_in_folio(folio, size); | |
1580 | ||
1581 | if (!folio->mapping) | |
1582 | return -EFAULT; | |
1583 | ||
1584 | /* folio is wholly inside EOF */ | |
1585 | if (folio_next_index(folio) - 1 < index) | |
1586 | return folio_size(folio); | |
1587 | /* folio is wholly past EOF */ | |
1588 | if (folio->index > index || !offset) | |
1589 | return -EFAULT; | |
1590 | /* folio is partially inside EOF */ | |
1591 | return offset; | |
1592 | } | |
1593 | ||
243145bc AG |
1594 | /** |
1595 | * page_mkwrite_check_truncate - check if page was truncated | |
1596 | * @page: the page to check | |
1597 | * @inode: the inode to check the page against | |
1598 | * | |
1599 | * Returns the number of bytes in the page up to EOF, | |
1600 | * or -EFAULT if the page was truncated. | |
1601 | */ | |
1602 | static inline int page_mkwrite_check_truncate(struct page *page, | |
1603 | struct inode *inode) | |
1604 | { | |
1605 | loff_t size = i_size_read(inode); | |
1606 | pgoff_t index = size >> PAGE_SHIFT; | |
1607 | int offset = offset_in_page(size); | |
1608 | ||
1609 | if (page->mapping != inode->i_mapping) | |
1610 | return -EFAULT; | |
1611 | ||
1612 | /* page is wholly inside EOF */ | |
1613 | if (page->index < index) | |
1614 | return PAGE_SIZE; | |
1615 | /* page is wholly past EOF */ | |
1616 | if (page->index > index || !offset) | |
1617 | return -EFAULT; | |
1618 | /* page is partially inside EOF */ | |
1619 | return offset; | |
1620 | } | |
1621 | ||
24addd84 | 1622 | /** |
9eb7c76d | 1623 | * i_blocks_per_folio - How many blocks fit in this folio. |
24addd84 | 1624 | * @inode: The inode which contains the blocks. |
9eb7c76d | 1625 | * @folio: The folio. |
24addd84 | 1626 | * |
9eb7c76d | 1627 | * If the block size is larger than the size of this folio, return zero. |
24addd84 | 1628 | * |
9eb7c76d | 1629 | * Context: The caller should hold a refcount on the folio to prevent it |
24addd84 | 1630 | * from being split. |
9eb7c76d | 1631 | * Return: The number of filesystem blocks covered by this folio. |
24addd84 | 1632 | */ |
9eb7c76d MWO |
1633 | static inline |
1634 | unsigned int i_blocks_per_folio(struct inode *inode, struct folio *folio) | |
1635 | { | |
1636 | return folio_size(folio) >> inode->i_blkbits; | |
1637 | } | |
1da177e4 | 1638 | #endif /* _LINUX_PAGEMAP_H */ |