163 void release_pages(struct page **pages, int nr);
168 static inline struct address_space *page_mapping_file(struct page *page)  in page_mapping_file()  argument
170 	if (unlikely(PageSwapCache(page)))  in page_mapping_file()
172 	return page_mapping(page);  in page_mapping_file()
176  * speculatively take a reference to a page.
177  * If the page is free (_refcount == 0), then _refcount is untouched, and 0
181  * been used to lookup the page in the pagecache radix-tree (or page table):
187  * page has been finished with, no matter what it is subsequently allocated
194  * 1. find page in radix tree
196  * 3. check the page is still in pagecache (if no, goto 1)
201  * B. remove page from pagecache
202  * C. free the page
207  *   subsequently, B will complete and 1 will find no page, causing the
210  * It is possible that between 1 and 2, the page is removed then the exact same
211  * page is inserted into the same position in pagecache. That's OK: the
216  * will find the page or it will not. Likewise, the old find_get_page could run
219 static inline int __page_cache_add_speculative(struct page *page, int count)  in __page_cache_add_speculative()  argument
230 	 * found a page in the radix tree here, we have pinned its refcount by  in __page_cache_add_speculative()
234 	VM_BUG_ON_PAGE(page_count(page) == 0, page);  in __page_cache_add_speculative()
235 	page_ref_add(page, count);  in __page_cache_add_speculative()
238 	if (unlikely(!page_ref_add_unless(page, count, 0))) {  in __page_cache_add_speculative()
240 		 * Either the page has been freed, or will be freed.  in __page_cache_add_speculative()
247 	VM_BUG_ON_PAGE(PageTail(page), page);  in __page_cache_add_speculative()
252 static inline int page_cache_get_speculative(struct page *page)  in page_cache_get_speculative()  argument
254 	return __page_cache_add_speculative(page, 1);  in page_cache_get_speculative()
257 static inline int page_cache_add_speculative(struct page *page, int count)  in page_cache_add_speculative()  argument
259 	return __page_cache_add_speculative(page, count);  in page_cache_add_speculative()
263  * attach_page_private - Attach private data to a page.
264  * @page: Page to attach data to.
265  * @data: Data to attach to page.
267  * Attaching private data to a page increments the page's reference count.
268  * The data must be detached before the page will be freed.
270 static inline void attach_page_private(struct page *page, void *data)  in attach_page_private()  argument
272 	get_page(page);  in attach_page_private()
273 	set_page_private(page, (unsigned long)data);  in attach_page_private()
274 	SetPagePrivate(page);  in attach_page_private()
278  * detach_page_private - Detach private data from a page.
279  * @page: Page to detach data from.
281  * Removes the data that was previously attached to the page and decrements
282  * the refcount on the page.
284  * Return: Data that was attached to the page.
286 static inline void *detach_page_private(struct page *page)  in detach_page_private()  argument
288 	void *data = (void *)page_private(page);  in detach_page_private()
290 	if (!PagePrivate(page))  in detach_page_private()
292 	ClearPagePrivate(page);  in detach_page_private()
293 	set_page_private(page, 0);  in detach_page_private()
294 	put_page(page);  in detach_page_private()
300 extern struct page *__page_cache_alloc(gfp_t gfp);
302 static inline struct page *__page_cache_alloc(gfp_t gfp)  in __page_cache_alloc()
308 static inline struct page *page_cache_alloc(struct address_space *x)  in page_cache_alloc()
318 typedef int filler_t(void *, struct page *);
335 struct page *pagecache_get_page(struct address_space *mapping, pgoff_t offset,
339  * find_get_page - find and get a page reference
341  * @offset: the page index
343  * Looks up the page cache slot at @mapping & @offset.  If there is a
344  * page cache page, it is returned with an increased refcount.
348 static inline struct page *find_get_page(struct address_space *mapping,  in find_get_page()
354 static inline struct page *find_get_page_flags(struct address_space *mapping,  in find_get_page_flags()
361  * find_lock_page - locate, pin and lock a pagecache page
363  * @index: the page index
365  * Looks up the page cache entry at @mapping & @index.  If there is a
366  * page cache page, it is returned locked and with an increased
370  * Return: A struct page or %NULL if there is no page in the cache for this
373 static inline struct page *find_lock_page(struct address_space *mapping,  in find_lock_page()
380  * find_lock_head - Locate, pin and lock a pagecache page.
382  * @index: The page index.
384  * Looks up the page cache entry at @mapping & @index.  If there is a
385  * page cache page, its head page is returned locked and with an increased
389  * Return: A struct page which is !PageTail, or %NULL if there is no page
392 static inline struct page *find_lock_head(struct address_space *mapping,  in find_lock_head()
399  * find_or_create_page - locate or add a pagecache page
400  * @mapping: the page's address_space
401  * @index: the page's index into the mapping
402  * @gfp_mask: page allocation mode
404  * Looks up the page cache slot at @mapping & @offset.  If there is a
405  * page cache page, it is returned locked and with an increased
408  * If the page is not present, a new page is allocated using @gfp_mask
409  * and added to the page cache and the VM's LRU list.  The page is
417 static inline struct page *find_or_create_page(struct address_space *mapping,  in find_or_create_page()
426  * grab_cache_page_nowait - returns locked page at given index in given cache
428  * @index: the page index
430  * Same as grab_cache_page(), but do not wait if the page is unavailable.
432  * be regenerated if the page couldn't be grabbed.  This routine should
433  * be safe to call while holding the lock for another page.
435  * Clear __GFP_FS when allocating the page to avoid recursion into the fs
436  * and deadlock against the caller's locked page.
438 static inline struct page *grab_cache_page_nowait(struct address_space *mapping,  in grab_cache_page_nowait()
446 /* Does this page contain this index? */
447 static inline bool thp_contains(struct page *head, pgoff_t index)  in thp_contains()
449 	/* HugeTLBfs indexes the page cache in units of hpage_size */  in thp_contains()
456  * Given the page we found in the page cache, return the page corresponding
459 static inline struct page *find_subpage(struct page *head, pgoff_t index)  in find_subpage()
461 	/* HugeTLBfs wants the head page regardless */  in find_subpage()
472 			struct page **pages);
475 			struct page **pages)  in find_get_pages()
481 			       unsigned int nr_pages, struct page **pages);
484 			struct page **pages);
487 			struct page **pages)  in find_get_pages_tag()
493 struct page *grab_cache_page_write_begin(struct address_space *mapping,
497  * Returns locked page at given index in given cache, creating it if needed.
499 static inline struct page *grab_cache_page(struct address_space *mapping,  in grab_cache_page()
505 extern struct page * read_cache_page(struct address_space *mapping,
507 extern struct page * read_cache_page_gfp(struct address_space *mapping,
512 static inline struct page *read_mapping_page(struct address_space *mapping,  in read_mapping_page()
519  * Get index of the page within radix-tree (but not for hugetlb pages).
522 static inline pgoff_t page_to_index(struct page *page)  in page_to_index()  argument
524 	struct page *head;  in page_to_index()
526 	if (likely(!PageTransTail(page)))  in page_to_index()
527 		return page->index;  in page_to_index()
529 	head = compound_head(page);  in page_to_index()
532 	 *  head page  in page_to_index()
534 	return head->index + page - head;  in page_to_index()
537 extern pgoff_t hugetlb_basepage_index(struct page *page);
543 static inline pgoff_t page_to_pgoff(struct page *page)  in page_to_pgoff()  argument
545 	if (unlikely(PageHuge(page)))  in page_to_pgoff()
546 		return hugetlb_basepage_index(page);  in page_to_pgoff()
547 	return page_to_index(page);  in page_to_pgoff()
551  * Return byte-offset into filesystem object for page.
553 static inline loff_t page_offset(struct page *page)  in page_offset()  argument
555 	return ((loff_t)page->index) << PAGE_SHIFT;  in page_offset()
558 static inline loff_t page_file_offset(struct page *page)  in page_file_offset()  argument
560 	return ((loff_t)page_index(page)) << PAGE_SHIFT;  in page_file_offset()
578 	struct page *page;  member
584 	struct page *page;  member
592 	if (wait_page->page != key->page)  in wake_page_match()
602 extern void __lock_page(struct page *page);
603 extern int __lock_page_killable(struct page *page);
604 extern int __lock_page_async(struct page *page, struct wait_page_queue *wait);
605 extern int __lock_page_or_retry(struct page *page, struct mm_struct *mm,
607 extern void unlock_page(struct page *page);
610  * Return true if the page was successfully locked
612 static inline int trylock_page(struct page *page)  in trylock_page()  argument
614 	page = compound_head(page);  in trylock_page()
615 	return (likely(!test_and_set_bit_lock(PG_locked, &page->flags)));  in trylock_page()
619  * lock_page may only be called if we have the page's inode pinned.
621 static inline void lock_page(struct page *page)  in lock_page()  argument
624 	if (!trylock_page(page))  in lock_page()
625 		__lock_page(page);  in lock_page()
630  * signals.  It returns 0 if it locked the page and -EINTR if it was
633 static inline int lock_page_killable(struct page *page)  in lock_page_killable()  argument
636 	if (!trylock_page(page))  in lock_page_killable()
637 		return __lock_page_killable(page);  in lock_page_killable()
642  * lock_page_async - Lock the page, unless this would block. If the page
643  * is already locked, then queue a callback when the page becomes unlocked.
646  * Returns 0 if the page is locked successfully, or -EIOCBQUEUED if the page
649 static inline int lock_page_async(struct page *page,  in lock_page_async()  argument
652 	if (!trylock_page(page))  in lock_page_async()
653 		return __lock_page_async(page, wait);  in lock_page_async()
658  * lock_page_or_retry - Lock the page, unless this would block and the
664 static inline int lock_page_or_retry(struct page *page, struct mm_struct *mm,  in lock_page_or_retry()  argument
668 	return trylock_page(page) || __lock_page_or_retry(page, mm, flags);  in lock_page_or_retry()
675 extern void wait_on_page_bit(struct page *page, int bit_nr);
676 extern int wait_on_page_bit_killable(struct page *page, int bit_nr);
679  * Wait for a page to be unlocked.
681  * This must be called with the caller "holding" the page,
682  * ie with increased "page->count" so that the page won't
685 static inline void wait_on_page_locked(struct page *page)  in wait_on_page_locked()  argument
687 	if (PageLocked(page))  in wait_on_page_locked()
688 		wait_on_page_bit(compound_head(page), PG_locked);  in wait_on_page_locked()
691 static inline int wait_on_page_locked_killable(struct page *page)  in wait_on_page_locked_killable()  argument
693 	if (!PageLocked(page))  in wait_on_page_locked_killable()
695 	return wait_on_page_bit_killable(compound_head(page), PG_locked);  in wait_on_page_locked_killable()
698 int put_and_wait_on_page_locked(struct page *page, int state);
699 void wait_on_page_writeback(struct page *page);
700 int wait_on_page_writeback_killable(struct page *page);
701 extern void end_page_writeback(struct page *page);
702 void wait_for_stable_page(struct page *page);
704 void __set_page_dirty(struct page *, struct address_space *, int warn);
705 int __set_page_dirty_nobuffers(struct page *page);
706 int __set_page_dirty_no_writeback(struct page *page);
708 void page_endio(struct page *page, bool is_write, int err);
711  * set_page_private_2 - Set PG_private_2 on a page and take a ref
712  * @page: The page.
714  * Set the PG_private_2 flag on a page and take the reference needed for the VM
719 static inline void set_page_private_2(struct page *page)  in set_page_private_2()  argument
721 	page = compound_head(page);  in set_page_private_2()
722 	get_page(page);  in set_page_private_2()
723 	SetPagePrivate2(page);  in set_page_private_2()
726 void end_page_private_2(struct page *page);
727 void wait_on_page_private_2(struct page *page);
728 int wait_on_page_private_2_killable(struct page *page);
731  * Add an arbitrary waiter to a page's wait queue
733 extern void add_page_wait_queue(struct page *page, wait_queue_entry_t *waiter);
757 	/* Check whether the range spilled into the next page. */  in fault_in_pages_writeable()
782 	/* Check whether the range spilled into the next page. */  in fault_in_pages_readable()
792 int add_to_page_cache_locked(struct page *page, struct address_space *mapping,
794 int add_to_page_cache_lru(struct page *page, struct address_space *mapping,
796 extern void delete_from_page_cache(struct page *page);
797 extern void __delete_from_page_cache(struct page *page, void *shadow);
798 void replace_page_cache_page(struct page *old, struct page *new);
806  * the page is new, so we can just run __SetPageLocked() against it.
808 static inline int add_to_page_cache(struct page *page,  in add_to_page_cache()  argument
813 	__SetPageLocked(page);  in add_to_page_cache()
814 	error = add_to_page_cache_locked(page, mapping, offset, gfp_mask);  in add_to_page_cache()
816 		__ClearPageLocked(page);  in add_to_page_cache()
826  * each page in the request.
859 void page_cache_async_ra(struct readahead_control *, struct page *,
869  * @index: Index of first page to be read.
891  * @page: The page at @index which triggered the readahead call.
892  * @index: Index of first page to be read.
895  * page_cache_async_readahead() should be called when a page is used which
903 		struct page *page, pgoff_t index, unsigned long req_count)  in page_cache_async_readahead()  argument
906 	page_cache_async_ra(&ractl, page, req_count);  in page_cache_async_readahead()
910  * readahead_page - Get the next page to read.
913  * Context: The page is locked and has an elevated refcount.  The caller
914  * should decreases the refcount once the page has been submitted for I/O
915  * and unlock the page once all I/O to that page has completed.
916  * Return: A pointer to the next page, or %NULL if we are done.
918 static inline struct page *readahead_page(struct readahead_control *rac)  in readahead_page()
920 	struct page *page;  in readahead_page()  local
931 	page = xa_load(&rac->mapping->i_pages, rac->_index);  in readahead_page()
932 	VM_BUG_ON_PAGE(!PageLocked(page), page);  in readahead_page()
933 	rac->_batch_count = thp_nr_pages(page);  in readahead_page()
935 	return page;  in readahead_page()
939 		struct page **array, unsigned int array_sz)  in __readahead_batch()
943 	struct page *page;  in __readahead_batch()  local
952 	xas_for_each(&xas, page, rac->_index + rac->_nr_pages - 1) {  in __readahead_batch()
953 		if (xas_retry(&xas, page))  in __readahead_batch()
955 		VM_BUG_ON_PAGE(!PageLocked(page), page);  in __readahead_batch()
956 		VM_BUG_ON_PAGE(PageTail(page), page);  in __readahead_batch()
957 		array[i++] = page;  in __readahead_batch()
958 		rac->_batch_count += thp_nr_pages(page);  in __readahead_batch()
961 		 * The page cache isn't using multi-index entries yet,  in __readahead_batch()
963 		 * next index.  This can be removed once the page cache  in __readahead_batch()
966 		if (PageHead(page))  in __readahead_batch()
980  * @array: An array of pointers to struct page.
983  * should decreases the refcount once the page has been submitted for I/O
984  * and unlock the page once all I/O to that page has completed.
1010  * readahead_index - The index of the first page in this readahead request.
1043  * page_mkwrite_check_truncate - check if page was truncated
1044  * @page: the page to check
1045  * @inode: the inode to check the page against
1047  * Returns the number of bytes in the page up to EOF,
1048  * or -EFAULT if the page was truncated.
1050 static inline int page_mkwrite_check_truncate(struct page *page,  in page_mkwrite_check_truncate()  argument
1057 	if (page->mapping != inode->i_mapping)  in page_mkwrite_check_truncate()
1060 	/* page is wholly inside EOF */  in page_mkwrite_check_truncate()
1061 	if (page->index < index)  in page_mkwrite_check_truncate()
1063 	/* page is wholly past EOF */  in page_mkwrite_check_truncate()
1064 	if (page->index > index || !offset)  in page_mkwrite_check_truncate()
1066 	/* page is partially inside EOF */  in page_mkwrite_check_truncate()
1071  * i_blocks_per_page - How many blocks fit in this page.
1073  * @page: The page (head page if the page is a THP).
1075  * If the block size is larger than the size of this page, return zero.
1077  * Context: The caller should hold a refcount on the page to prevent it
1079  * Return: The number of filesystem blocks covered by this page.
1082 unsigned int i_blocks_per_page(struct inode *inode, struct page *page)  in i_blocks_per_page()  argument
1084 	return thp_size(page) >> inode->i_blkbits;  in i_blocks_per_page()