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10#include <linux/kernel.h>
11#include <linux/backing-dev.h>
12#include <linux/dax.h>
13#include <linux/gfp.h>
14#include <linux/mm.h>
15#include <linux/swap.h>
16#include <linux/export.h>
17#include <linux/pagemap.h>
18#include <linux/highmem.h>
19#include <linux/pagevec.h>
20#include <linux/task_io_accounting_ops.h>
21#include <linux/buffer_head.h>
22
23#include <linux/shmem_fs.h>
24#include <linux/cleancache.h>
25#include <linux/rmap.h>
26#include "internal.h"
27
28
29
30
31
32
33static inline void __clear_shadow_entry(struct address_space *mapping,
34 pgoff_t index, void *entry)
35{
36 struct radix_tree_node *node;
37 void **slot;
38
39 if (!__radix_tree_lookup(&mapping->i_pages, index, &node, &slot))
40 return;
41 if (*slot != entry)
42 return;
43 __radix_tree_replace(&mapping->i_pages, node, slot, NULL,
44 workingset_update_node);
45 mapping->nrexceptional--;
46}
47
48static void clear_shadow_entry(struct address_space *mapping, pgoff_t index,
49 void *entry)
50{
51 xa_lock_irq(&mapping->i_pages);
52 __clear_shadow_entry(mapping, index, entry);
53 xa_unlock_irq(&mapping->i_pages);
54}
55
56
57
58
59
60
61static void truncate_exceptional_pvec_entries(struct address_space *mapping,
62 struct pagevec *pvec, pgoff_t *indices,
63 pgoff_t end)
64{
65 int i, j;
66 bool dax, lock;
67
68
69 if (shmem_mapping(mapping))
70 return;
71
72 for (j = 0; j < pagevec_count(pvec); j++)
73 if (radix_tree_exceptional_entry(pvec->pages[j]))
74 break;
75
76 if (j == pagevec_count(pvec))
77 return;
78
79 dax = dax_mapping(mapping);
80 lock = !dax && indices[j] < end;
81 if (lock)
82 xa_lock_irq(&mapping->i_pages);
83
84 for (i = j; i < pagevec_count(pvec); i++) {
85 struct page *page = pvec->pages[i];
86 pgoff_t index = indices[i];
87
88 if (!radix_tree_exceptional_entry(page)) {
89 pvec->pages[j++] = page;
90 continue;
91 }
92
93 if (index >= end)
94 continue;
95
96 if (unlikely(dax)) {
97 dax_delete_mapping_entry(mapping, index);
98 continue;
99 }
100
101 __clear_shadow_entry(mapping, index, page);
102 }
103
104 if (lock)
105 xa_unlock_irq(&mapping->i_pages);
106 pvec->nr = j;
107}
108
109
110
111
112
113static int invalidate_exceptional_entry(struct address_space *mapping,
114 pgoff_t index, void *entry)
115{
116
117 if (shmem_mapping(mapping) || dax_mapping(mapping))
118 return 1;
119 clear_shadow_entry(mapping, index, entry);
120 return 1;
121}
122
123
124
125
126
127static int invalidate_exceptional_entry2(struct address_space *mapping,
128 pgoff_t index, void *entry)
129{
130
131 if (shmem_mapping(mapping))
132 return 1;
133 if (dax_mapping(mapping))
134 return dax_invalidate_mapping_entry_sync(mapping, index);
135 clear_shadow_entry(mapping, index, entry);
136 return 1;
137}
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153
154void do_invalidatepage(struct page *page, unsigned int offset,
155 unsigned int length)
156{
157 void (*invalidatepage)(struct page *, unsigned int, unsigned int);
158
159 invalidatepage = page->mapping->a_ops->invalidatepage;
160#ifdef CONFIG_BLOCK
161 if (!invalidatepage)
162 invalidatepage = block_invalidatepage;
163#endif
164 if (invalidatepage)
165 (*invalidatepage)(page, offset, length);
166}
167
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177
178static void
179truncate_cleanup_page(struct address_space *mapping, struct page *page)
180{
181 if (page_mapped(page)) {
182 pgoff_t nr = PageTransHuge(page) ? HPAGE_PMD_NR : 1;
183 unmap_mapping_pages(mapping, page->index, nr, false);
184 }
185
186 if (page_has_private(page))
187 do_invalidatepage(page, 0, PAGE_SIZE);
188
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192
193
194 cancel_dirty_page(page);
195 ClearPageMappedToDisk(page);
196}
197
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204
205
206static int
207invalidate_complete_page(struct address_space *mapping, struct page *page)
208{
209 int ret;
210
211 if (page->mapping != mapping)
212 return 0;
213
214 if (page_has_private(page) && !try_to_release_page(page, 0))
215 return 0;
216
217 ret = remove_mapping(mapping, page);
218
219 return ret;
220}
221
222int truncate_inode_page(struct address_space *mapping, struct page *page)
223{
224 VM_BUG_ON_PAGE(PageTail(page), page);
225
226 if (page->mapping != mapping)
227 return -EIO;
228
229 truncate_cleanup_page(mapping, page);
230 delete_from_page_cache(page);
231 return 0;
232}
233
234
235
236
237int generic_error_remove_page(struct address_space *mapping, struct page *page)
238{
239 if (!mapping)
240 return -EINVAL;
241
242
243
244
245 if (!S_ISREG(mapping->host->i_mode))
246 return -EIO;
247 return truncate_inode_page(mapping, page);
248}
249EXPORT_SYMBOL(generic_error_remove_page);
250
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255
256
257int invalidate_inode_page(struct page *page)
258{
259 struct address_space *mapping = page_mapping(page);
260 if (!mapping)
261 return 0;
262 if (PageDirty(page) || PageWriteback(page))
263 return 0;
264 if (page_mapped(page))
265 return 0;
266 return invalidate_complete_page(mapping, page);
267}
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293void truncate_inode_pages_range(struct address_space *mapping,
294 loff_t lstart, loff_t lend)
295{
296 pgoff_t start;
297 pgoff_t end;
298 unsigned int partial_start;
299 unsigned int partial_end;
300 struct pagevec pvec;
301 pgoff_t indices[PAGEVEC_SIZE];
302 pgoff_t index;
303 int i;
304
305 if (mapping->nrpages == 0 && mapping->nrexceptional == 0)
306 goto out;
307
308
309 partial_start = lstart & (PAGE_SIZE - 1);
310 partial_end = (lend + 1) & (PAGE_SIZE - 1);
311
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316
317
318 start = (lstart + PAGE_SIZE - 1) >> PAGE_SHIFT;
319 if (lend == -1)
320
321
322
323
324
325 end = -1;
326 else
327 end = (lend + 1) >> PAGE_SHIFT;
328
329 pagevec_init(&pvec);
330 index = start;
331 while (index < end && pagevec_lookup_entries(&pvec, mapping, index,
332 min(end - index, (pgoff_t)PAGEVEC_SIZE),
333 indices)) {
334
335
336
337
338
339 struct pagevec locked_pvec;
340
341 pagevec_init(&locked_pvec);
342 for (i = 0; i < pagevec_count(&pvec); i++) {
343 struct page *page = pvec.pages[i];
344
345
346 index = indices[i];
347 if (index >= end)
348 break;
349
350 if (radix_tree_exceptional_entry(page))
351 continue;
352
353 if (!trylock_page(page))
354 continue;
355 WARN_ON(page_to_index(page) != index);
356 if (PageWriteback(page)) {
357 unlock_page(page);
358 continue;
359 }
360 if (page->mapping != mapping) {
361 unlock_page(page);
362 continue;
363 }
364 pagevec_add(&locked_pvec, page);
365 }
366 for (i = 0; i < pagevec_count(&locked_pvec); i++)
367 truncate_cleanup_page(mapping, locked_pvec.pages[i]);
368 delete_from_page_cache_batch(mapping, &locked_pvec);
369 for (i = 0; i < pagevec_count(&locked_pvec); i++)
370 unlock_page(locked_pvec.pages[i]);
371 truncate_exceptional_pvec_entries(mapping, &pvec, indices, end);
372 pagevec_release(&pvec);
373 cond_resched();
374 index++;
375 }
376 if (partial_start) {
377 struct page *page = find_lock_page(mapping, start - 1);
378 if (page) {
379 unsigned int top = PAGE_SIZE;
380 if (start > end) {
381
382 top = partial_end;
383 partial_end = 0;
384 }
385 wait_on_page_writeback(page);
386 zero_user_segment(page, partial_start, top);
387 cleancache_invalidate_page(mapping, page);
388 if (page_has_private(page))
389 do_invalidatepage(page, partial_start,
390 top - partial_start);
391 unlock_page(page);
392 put_page(page);
393 }
394 }
395 if (partial_end) {
396 struct page *page = find_lock_page(mapping, end);
397 if (page) {
398 wait_on_page_writeback(page);
399 zero_user_segment(page, 0, partial_end);
400 cleancache_invalidate_page(mapping, page);
401 if (page_has_private(page))
402 do_invalidatepage(page, 0,
403 partial_end);
404 unlock_page(page);
405 put_page(page);
406 }
407 }
408
409
410
411
412 if (start >= end)
413 goto out;
414
415 index = start;
416 for ( ; ; ) {
417 cond_resched();
418 if (!pagevec_lookup_entries(&pvec, mapping, index,
419 min(end - index, (pgoff_t)PAGEVEC_SIZE), indices)) {
420
421 if (index == start)
422 break;
423
424 index = start;
425 continue;
426 }
427 if (index == start && indices[0] >= end) {
428
429 pagevec_remove_exceptionals(&pvec);
430 pagevec_release(&pvec);
431 break;
432 }
433
434 for (i = 0; i < pagevec_count(&pvec); i++) {
435 struct page *page = pvec.pages[i];
436
437
438 index = indices[i];
439 if (index >= end) {
440
441 index = start - 1;
442 break;
443 }
444
445 if (radix_tree_exceptional_entry(page))
446 continue;
447
448 lock_page(page);
449 WARN_ON(page_to_index(page) != index);
450 wait_on_page_writeback(page);
451 truncate_inode_page(mapping, page);
452 unlock_page(page);
453 }
454 truncate_exceptional_pvec_entries(mapping, &pvec, indices, end);
455 pagevec_release(&pvec);
456 index++;
457 }
458
459out:
460 cleancache_invalidate_inode(mapping);
461}
462EXPORT_SYMBOL(truncate_inode_pages_range);
463
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475
476void truncate_inode_pages(struct address_space *mapping, loff_t lstart)
477{
478 truncate_inode_pages_range(mapping, lstart, (loff_t)-1);
479}
480EXPORT_SYMBOL(truncate_inode_pages);
481
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490
491void truncate_inode_pages_final(struct address_space *mapping)
492{
493 unsigned long nrexceptional;
494 unsigned long nrpages;
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503 mapping_set_exiting(mapping);
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510 nrpages = mapping->nrpages;
511 smp_rmb();
512 nrexceptional = mapping->nrexceptional;
513
514 if (nrpages || nrexceptional) {
515
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519
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521 xa_lock_irq(&mapping->i_pages);
522 xa_unlock_irq(&mapping->i_pages);
523
524 truncate_inode_pages(mapping, 0);
525 }
526}
527EXPORT_SYMBOL(truncate_inode_pages_final);
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541
542unsigned long invalidate_mapping_pages(struct address_space *mapping,
543 pgoff_t start, pgoff_t end)
544{
545 pgoff_t indices[PAGEVEC_SIZE];
546 struct pagevec pvec;
547 pgoff_t index = start;
548 unsigned long ret;
549 unsigned long count = 0;
550 int i;
551
552 pagevec_init(&pvec);
553 while (index <= end && pagevec_lookup_entries(&pvec, mapping, index,
554 min(end - index, (pgoff_t)PAGEVEC_SIZE - 1) + 1,
555 indices)) {
556 for (i = 0; i < pagevec_count(&pvec); i++) {
557 struct page *page = pvec.pages[i];
558
559
560 index = indices[i];
561 if (index > end)
562 break;
563
564 if (radix_tree_exceptional_entry(page)) {
565 invalidate_exceptional_entry(mapping, index,
566 page);
567 continue;
568 }
569
570 if (!trylock_page(page))
571 continue;
572
573 WARN_ON(page_to_index(page) != index);
574
575
576 if (PageTransTail(page)) {
577 unlock_page(page);
578 continue;
579 } else if (PageTransHuge(page)) {
580 index += HPAGE_PMD_NR - 1;
581 i += HPAGE_PMD_NR - 1;
582
583
584
585
586
587 if (index > end) {
588 unlock_page(page);
589 continue;
590 }
591 }
592
593 ret = invalidate_inode_page(page);
594 unlock_page(page);
595
596
597
598
599 if (!ret)
600 deactivate_file_page(page);
601 count += ret;
602 }
603 pagevec_remove_exceptionals(&pvec);
604 pagevec_release(&pvec);
605 cond_resched();
606 index++;
607 }
608 return count;
609}
610EXPORT_SYMBOL(invalidate_mapping_pages);
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618
619static int
620invalidate_complete_page2(struct address_space *mapping, struct page *page)
621{
622 unsigned long flags;
623
624 if (page->mapping != mapping)
625 return 0;
626
627 if (page_has_private(page) && !try_to_release_page(page, GFP_KERNEL))
628 return 0;
629
630 xa_lock_irqsave(&mapping->i_pages, flags);
631 if (PageDirty(page))
632 goto failed;
633
634 BUG_ON(page_has_private(page));
635 __delete_from_page_cache(page, NULL);
636 xa_unlock_irqrestore(&mapping->i_pages, flags);
637
638 if (mapping->a_ops->freepage)
639 mapping->a_ops->freepage(page);
640
641 put_page(page);
642 return 1;
643failed:
644 xa_unlock_irqrestore(&mapping->i_pages, flags);
645 return 0;
646}
647
648static int do_launder_page(struct address_space *mapping, struct page *page)
649{
650 if (!PageDirty(page))
651 return 0;
652 if (page->mapping != mapping || mapping->a_ops->launder_page == NULL)
653 return 0;
654 return mapping->a_ops->launder_page(page);
655}
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667
668int invalidate_inode_pages2_range(struct address_space *mapping,
669 pgoff_t start, pgoff_t end)
670{
671 pgoff_t indices[PAGEVEC_SIZE];
672 struct pagevec pvec;
673 pgoff_t index;
674 int i;
675 int ret = 0;
676 int ret2 = 0;
677 int did_range_unmap = 0;
678
679 if (mapping->nrpages == 0 && mapping->nrexceptional == 0)
680 goto out;
681
682 pagevec_init(&pvec);
683 index = start;
684 while (index <= end && pagevec_lookup_entries(&pvec, mapping, index,
685 min(end - index, (pgoff_t)PAGEVEC_SIZE - 1) + 1,
686 indices)) {
687 for (i = 0; i < pagevec_count(&pvec); i++) {
688 struct page *page = pvec.pages[i];
689
690
691 index = indices[i];
692 if (index > end)
693 break;
694
695 if (radix_tree_exceptional_entry(page)) {
696 if (!invalidate_exceptional_entry2(mapping,
697 index, page))
698 ret = -EBUSY;
699 continue;
700 }
701
702 lock_page(page);
703 WARN_ON(page_to_index(page) != index);
704 if (page->mapping != mapping) {
705 unlock_page(page);
706 continue;
707 }
708 wait_on_page_writeback(page);
709 if (page_mapped(page)) {
710 if (!did_range_unmap) {
711
712
713
714 unmap_mapping_pages(mapping, index,
715 (1 + end - index), false);
716 did_range_unmap = 1;
717 } else {
718
719
720
721 unmap_mapping_pages(mapping, index,
722 1, false);
723 }
724 }
725 BUG_ON(page_mapped(page));
726 ret2 = do_launder_page(mapping, page);
727 if (ret2 == 0) {
728 if (!invalidate_complete_page2(mapping, page))
729 ret2 = -EBUSY;
730 }
731 if (ret2 < 0)
732 ret = ret2;
733 unlock_page(page);
734 }
735 pagevec_remove_exceptionals(&pvec);
736 pagevec_release(&pvec);
737 cond_resched();
738 index++;
739 }
740
741
742
743
744
745
746
747 if (dax_mapping(mapping)) {
748 unmap_mapping_pages(mapping, start, end - start + 1, false);
749 }
750out:
751 cleancache_invalidate_inode(mapping);
752 return ret;
753}
754EXPORT_SYMBOL_GPL(invalidate_inode_pages2_range);
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764
765int invalidate_inode_pages2(struct address_space *mapping)
766{
767 return invalidate_inode_pages2_range(mapping, 0, -1);
768}
769EXPORT_SYMBOL_GPL(invalidate_inode_pages2);
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786void truncate_pagecache(struct inode *inode, loff_t newsize)
787{
788 struct address_space *mapping = inode->i_mapping;
789 loff_t holebegin = round_up(newsize, PAGE_SIZE);
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799
800 unmap_mapping_range(mapping, holebegin, 0, 1);
801 truncate_inode_pages(mapping, newsize);
802 unmap_mapping_range(mapping, holebegin, 0, 1);
803}
804EXPORT_SYMBOL(truncate_pagecache);
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819void truncate_setsize(struct inode *inode, loff_t newsize)
820{
821 loff_t oldsize = inode->i_size;
822
823 i_size_write(inode, newsize);
824 if (newsize > oldsize)
825 pagecache_isize_extended(inode, oldsize, newsize);
826 truncate_pagecache(inode, newsize);
827}
828EXPORT_SYMBOL(truncate_setsize);
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849void pagecache_isize_extended(struct inode *inode, loff_t from, loff_t to)
850{
851 int bsize = i_blocksize(inode);
852 loff_t rounded_from;
853 struct page *page;
854 pgoff_t index;
855
856 WARN_ON(to > inode->i_size);
857
858 if (from >= to || bsize == PAGE_SIZE)
859 return;
860
861 rounded_from = round_up(from, bsize);
862 if (to <= rounded_from || !(rounded_from & (PAGE_SIZE - 1)))
863 return;
864
865 index = from >> PAGE_SHIFT;
866 page = find_lock_page(inode->i_mapping, index);
867
868 if (!page)
869 return;
870
871
872
873
874 if (page_mkclean(page))
875 set_page_dirty(page);
876 unlock_page(page);
877 put_page(page);
878}
879EXPORT_SYMBOL(pagecache_isize_extended);
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893
894void truncate_pagecache_range(struct inode *inode, loff_t lstart, loff_t lend)
895{
896 struct address_space *mapping = inode->i_mapping;
897 loff_t unmap_start = round_up(lstart, PAGE_SIZE);
898 loff_t unmap_end = round_down(1 + lend, PAGE_SIZE) - 1;
899
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910
911
912 if ((u64)unmap_end > (u64)unmap_start)
913 unmap_mapping_range(mapping, unmap_start,
914 1 + unmap_end - unmap_start, 0);
915 truncate_inode_pages_range(mapping, lstart, lend);
916}
917EXPORT_SYMBOL(truncate_pagecache_range);
918