diff options
Diffstat (limited to 'include/linux/pagemap.h')
| -rw-r--r-- | include/linux/pagemap.h | 1561 |
1 files changed, 1561 insertions, 0 deletions
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h new file mode 100644 index 000000000..8c9608b21 --- /dev/null +++ b/include/linux/pagemap.h @@ -0,0 +1,1561 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _LINUX_PAGEMAP_H +#define _LINUX_PAGEMAP_H + +/* + * Copyright 1995 Linus Torvalds + */ +#include <linux/mm.h> +#include <linux/fs.h> +#include <linux/list.h> +#include <linux/highmem.h> +#include <linux/compiler.h> +#include <linux/uaccess.h> +#include <linux/gfp.h> +#include <linux/bitops.h> +#include <linux/hardirq.h> /* for in_interrupt() */ +#include <linux/hugetlb_inline.h> + +struct folio_batch; + +unsigned long invalidate_mapping_pages(struct address_space *mapping, + pgoff_t start, pgoff_t end); + +static inline void invalidate_remote_inode(struct inode *inode) +{ + if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || + S_ISLNK(inode->i_mode)) + invalidate_mapping_pages(inode->i_mapping, 0, -1); +} +int invalidate_inode_pages2(struct address_space *mapping); +int invalidate_inode_pages2_range(struct address_space *mapping, + pgoff_t start, pgoff_t end); +int kiocb_invalidate_pages(struct kiocb *iocb, size_t count); +void kiocb_invalidate_post_direct_write(struct kiocb *iocb, size_t count); + +int write_inode_now(struct inode *, int sync); +int filemap_fdatawrite(struct address_space *); +int filemap_flush(struct address_space *); +int filemap_fdatawait_keep_errors(struct address_space *mapping); +int filemap_fdatawait_range(struct address_space *, loff_t lstart, loff_t lend); +int filemap_fdatawait_range_keep_errors(struct address_space *mapping, + loff_t start_byte, loff_t end_byte); + +static inline int filemap_fdatawait(struct address_space *mapping) +{ + return filemap_fdatawait_range(mapping, 0, LLONG_MAX); +} + +bool filemap_range_has_page(struct address_space *, loff_t lstart, loff_t lend); +int filemap_write_and_wait_range(struct address_space *mapping, + loff_t lstart, loff_t lend); +int __filemap_fdatawrite_range(struct address_space *mapping, + loff_t start, loff_t end, int sync_mode); +int filemap_fdatawrite_range(struct address_space *mapping, + loff_t start, loff_t end); +int filemap_check_errors(struct address_space *mapping); +void __filemap_set_wb_err(struct address_space *mapping, int err); +int filemap_fdatawrite_wbc(struct address_space *mapping, + struct writeback_control *wbc); +int kiocb_write_and_wait(struct kiocb *iocb, size_t count); + +static inline int filemap_write_and_wait(struct address_space *mapping) +{ + return filemap_write_and_wait_range(mapping, 0, LLONG_MAX); +} + +/** + * filemap_set_wb_err - set a writeback error on an address_space + * @mapping: mapping in which to set writeback error + * @err: error to be set in mapping + * + * When writeback fails in some way, we must record that error so that + * userspace can be informed when fsync and the like are called. We endeavor + * to report errors on any file that was open at the time of the error. Some + * internal callers also need to know when writeback errors have occurred. + * + * When a writeback error occurs, most filesystems will want to call + * filemap_set_wb_err to record the error in the mapping so that it will be + * automatically reported whenever fsync is called on the file. + */ +static inline void filemap_set_wb_err(struct address_space *mapping, int err) +{ + /* Fastpath for common case of no error */ + if (unlikely(err)) + __filemap_set_wb_err(mapping, err); +} + +/** + * filemap_check_wb_err - has an error occurred since the mark was sampled? + * @mapping: mapping to check for writeback errors + * @since: previously-sampled errseq_t + * + * Grab the errseq_t value from the mapping, and see if it has changed "since" + * the given value was sampled. + * + * If it has then report the latest error set, otherwise return 0. + */ +static inline int filemap_check_wb_err(struct address_space *mapping, + errseq_t since) +{ + return errseq_check(&mapping->wb_err, since); +} + +/** + * filemap_sample_wb_err - sample the current errseq_t to test for later errors + * @mapping: mapping to be sampled + * + * Writeback errors are always reported relative to a particular sample point + * in the past. This function provides those sample points. + */ +static inline errseq_t filemap_sample_wb_err(struct address_space *mapping) +{ + return errseq_sample(&mapping->wb_err); +} + +/** + * file_sample_sb_err - sample the current errseq_t to test for later errors + * @file: file pointer to be sampled + * + * Grab the most current superblock-level errseq_t value for the given + * struct file. + */ +static inline errseq_t file_sample_sb_err(struct file *file) +{ + return errseq_sample(&file->f_path.dentry->d_sb->s_wb_err); +} + +/* + * Flush file data before changing attributes. Caller must hold any locks + * required to prevent further writes to this file until we're done setting + * flags. + */ +static inline int inode_drain_writes(struct inode *inode) +{ + inode_dio_wait(inode); + return filemap_write_and_wait(inode->i_mapping); +} + +static inline bool mapping_empty(struct address_space *mapping) +{ + return xa_empty(&mapping->i_pages); +} + +/* + * mapping_shrinkable - test if page cache state allows inode reclaim + * @mapping: the page cache mapping + * + * This checks the mapping's cache state for the pupose of inode + * reclaim and LRU management. + * + * The caller is expected to hold the i_lock, but is not required to + * hold the i_pages lock, which usually protects cache state. That's + * because the i_lock and the list_lru lock that protect the inode and + * its LRU state don't nest inside the irq-safe i_pages lock. + * + * Cache deletions are performed under the i_lock, which ensures that + * when an inode goes empty, it will reliably get queued on the LRU. + * + * Cache additions do not acquire the i_lock and may race with this + * check, in which case we'll report the inode as shrinkable when it + * has cache pages. This is okay: the shrinker also checks the + * refcount and the referenced bit, which will be elevated or set in + * the process of adding new cache pages to an inode. + */ +static inline bool mapping_shrinkable(struct address_space *mapping) +{ + void *head; + + /* + * On highmem systems, there could be lowmem pressure from the + * inodes before there is highmem pressure from the page + * cache. Make inodes shrinkable regardless of cache state. + */ + if (IS_ENABLED(CONFIG_HIGHMEM)) + return true; + + /* Cache completely empty? Shrink away. */ + head = rcu_access_pointer(mapping->i_pages.xa_head); + if (!head) + return true; + + /* + * The xarray stores single offset-0 entries directly in the + * head pointer, which allows non-resident page cache entries + * to escape the shadow shrinker's list of xarray nodes. The + * inode shrinker needs to pick them up under memory pressure. + */ + if (!xa_is_node(head) && xa_is_value(head)) + return true; + + return false; +} + +/* + * Bits in mapping->flags. + */ +enum mapping_flags { + AS_EIO = 0, /* IO error on async write */ + AS_ENOSPC = 1, /* ENOSPC on async write */ + AS_MM_ALL_LOCKS = 2, /* under mm_take_all_locks() */ + AS_UNEVICTABLE = 3, /* e.g., ramdisk, SHM_LOCK */ + AS_EXITING = 4, /* final truncate in progress */ + /* writeback related tags are not used */ + AS_NO_WRITEBACK_TAGS = 5, + AS_LARGE_FOLIO_SUPPORT = 6, + AS_RELEASE_ALWAYS, /* Call ->release_folio(), even if no private data */ + AS_STABLE_WRITES, /* must wait for writeback before modifying + folio contents */ +}; + +/** + * mapping_set_error - record a writeback error in the address_space + * @mapping: the mapping in which an error should be set + * @error: the error to set in the mapping + * + * When writeback fails in some way, we must record that error so that + * userspace can be informed when fsync and the like are called. We endeavor + * to report errors on any file that was open at the time of the error. Some + * internal callers also need to know when writeback errors have occurred. + * + * When a writeback error occurs, most filesystems will want to call + * mapping_set_error to record the error in the mapping so that it can be + * reported when the application calls fsync(2). + */ +static inline void mapping_set_error(struct address_space *mapping, int error) +{ + if (likely(!error)) + return; + + /* Record in wb_err for checkers using errseq_t based tracking */ + __filemap_set_wb_err(mapping, error); + + /* Record it in superblock */ + if (mapping->host) + errseq_set(&mapping->host->i_sb->s_wb_err, error); + + /* Record it in flags for now, for legacy callers */ + if (error == -ENOSPC) + set_bit(AS_ENOSPC, &mapping->flags); + else + set_bit(AS_EIO, &mapping->flags); +} + +static inline void mapping_set_unevictable(struct address_space *mapping) +{ + set_bit(AS_UNEVICTABLE, &mapping->flags); +} + +static inline void mapping_clear_unevictable(struct address_space *mapping) +{ + clear_bit(AS_UNEVICTABLE, &mapping->flags); +} + +static inline bool mapping_unevictable(struct address_space *mapping) +{ + return mapping && test_bit(AS_UNEVICTABLE, &mapping->flags); +} + +static inline void mapping_set_exiting(struct address_space *mapping) +{ + set_bit(AS_EXITING, &mapping->flags); +} + +static inline int mapping_exiting(struct address_space *mapping) +{ + return test_bit(AS_EXITING, &mapping->flags); +} + +static inline void mapping_set_no_writeback_tags(struct address_space *mapping) +{ + set_bit(AS_NO_WRITEBACK_TAGS, &mapping->flags); +} + +static inline int mapping_use_writeback_tags(struct address_space *mapping) +{ + return !test_bit(AS_NO_WRITEBACK_TAGS, &mapping->flags); +} + +static inline bool mapping_release_always(const struct address_space *mapping) +{ + return test_bit(AS_RELEASE_ALWAYS, &mapping->flags); +} + +static inline void mapping_set_release_always(struct address_space *mapping) +{ + set_bit(AS_RELEASE_ALWAYS, &mapping->flags); +} + +static inline void mapping_clear_release_always(struct address_space *mapping) +{ + clear_bit(AS_RELEASE_ALWAYS, &mapping->flags); +} + +static inline bool mapping_stable_writes(const struct address_space *mapping) +{ + return test_bit(AS_STABLE_WRITES, &mapping->flags); +} + +static inline void mapping_set_stable_writes(struct address_space *mapping) +{ + set_bit(AS_STABLE_WRITES, &mapping->flags); +} + +static inline void mapping_clear_stable_writes(struct address_space *mapping) +{ + clear_bit(AS_STABLE_WRITES, &mapping->flags); +} + +static inline gfp_t mapping_gfp_mask(struct address_space * mapping) +{ + return mapping->gfp_mask; +} + +/* Restricts the given gfp_mask to what the mapping allows. */ +static inline gfp_t mapping_gfp_constraint(struct address_space *mapping, + gfp_t gfp_mask) +{ + return mapping_gfp_mask(mapping) & gfp_mask; +} + +/* + * This is non-atomic. Only to be used before the mapping is activated. + * Probably needs a barrier... + */ +static inline void mapping_set_gfp_mask(struct address_space *m, gfp_t mask) +{ + m->gfp_mask = mask; +} + +/** + * mapping_set_large_folios() - Indicate the file supports large folios. + * @mapping: The file. + * + * The filesystem should call this function in its inode constructor to + * indicate that the VFS can use large folios to cache the contents of + * the file. + * + * Context: This should not be called while the inode is active as it + * is non-atomic. + */ +static inline void mapping_set_large_folios(struct address_space *mapping) +{ + __set_bit(AS_LARGE_FOLIO_SUPPORT, &mapping->flags); +} + +/* + * Large folio support currently depends on THP. These dependencies are + * being worked on but are not yet fixed. + */ +static inline bool mapping_large_folio_support(struct address_space *mapping) +{ + return IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && + test_bit(AS_LARGE_FOLIO_SUPPORT, &mapping->flags); +} + +static inline int filemap_nr_thps(struct address_space *mapping) +{ +#ifdef CONFIG_READ_ONLY_THP_FOR_FS + return atomic_read(&mapping->nr_thps); +#else + return 0; +#endif +} + +static inline void filemap_nr_thps_inc(struct address_space *mapping) +{ +#ifdef CONFIG_READ_ONLY_THP_FOR_FS + if (!mapping_large_folio_support(mapping)) + atomic_inc(&mapping->nr_thps); +#else + WARN_ON_ONCE(mapping_large_folio_support(mapping) == 0); +#endif +} + +static inline void filemap_nr_thps_dec(struct address_space *mapping) +{ +#ifdef CONFIG_READ_ONLY_THP_FOR_FS + if (!mapping_large_folio_support(mapping)) + atomic_dec(&mapping->nr_thps); +#else + WARN_ON_ONCE(mapping_large_folio_support(mapping) == 0); +#endif +} + +struct address_space *page_mapping(struct page *); +struct address_space *folio_mapping(struct folio *); +struct address_space *swapcache_mapping(struct folio *); + +/** + * folio_file_mapping - Find the mapping this folio belongs to. + * @folio: The folio. + * + * For folios which are in the page cache, return the mapping that this + * page belongs to. Folios in the swap cache return the mapping of the + * swap file or swap device where the data is stored. This is different + * from the mapping returned by folio_mapping(). The only reason to + * use it is if, like NFS, you return 0 from ->activate_swapfile. + * + * Do not call this for folios which aren't in the page cache or swap cache. + */ +static inline struct address_space *folio_file_mapping(struct folio *folio) +{ + if (unlikely(folio_test_swapcache(folio))) + return swapcache_mapping(folio); + + return folio->mapping; +} + +/** + * folio_flush_mapping - Find the file mapping this folio belongs to. + * @folio: The folio. + * + * For folios which are in the page cache, return the mapping that this + * page belongs to. Anonymous folios return NULL, even if they're in + * the swap cache. Other kinds of folio also return NULL. + * + * This is ONLY used by architecture cache flushing code. If you aren't + * writing cache flushing code, you want either folio_mapping() or + * folio_file_mapping(). + */ +static inline struct address_space *folio_flush_mapping(struct folio *folio) +{ + if (unlikely(folio_test_swapcache(folio))) + return NULL; + + return folio_mapping(folio); +} + +static inline struct address_space *page_file_mapping(struct page *page) +{ + return folio_file_mapping(page_folio(page)); +} + +/** + * folio_inode - Get the host inode for this folio. + * @folio: The folio. + * + * For folios which are in the page cache, return the inode that this folio + * belongs to. + * + * Do not call this for folios which aren't in the page cache. + */ +static inline struct inode *folio_inode(struct folio *folio) +{ + return folio->mapping->host; +} + +/** + * folio_attach_private - Attach private data to a folio. + * @folio: Folio to attach data to. + * @data: Data to attach to folio. + * + * Attaching private data to a folio increments the page's reference count. + * The data must be detached before the folio will be freed. + */ +static inline void folio_attach_private(struct folio *folio, void *data) +{ + folio_get(folio); + folio->private = data; + folio_set_private(folio); +} + +/** + * folio_change_private - Change private data on a folio. + * @folio: Folio to change the data on. + * @data: Data to set on the folio. + * + * Change the private data attached to a folio and return the old + * data. The page must previously have had data attached and the data + * must be detached before the folio will be freed. + * + * Return: Data that was previously attached to the folio. + */ +static inline void *folio_change_private(struct folio *folio, void *data) +{ + void *old = folio_get_private(folio); + + folio->private = data; + return old; +} + +/** + * folio_detach_private - Detach private data from a folio. + * @folio: Folio to detach data from. + * + * Removes the data that was previously attached to the folio and decrements + * the refcount on the page. + * + * Return: Data that was attached to the folio. + */ +static inline void *folio_detach_private(struct folio *folio) +{ + void *data = folio_get_private(folio); + + if (!folio_test_private(folio)) + return NULL; + folio_clear_private(folio); + folio->private = NULL; + folio_put(folio); + + return data; +} + +static inline void attach_page_private(struct page *page, void *data) +{ + folio_attach_private(page_folio(page), data); +} + +static inline void *detach_page_private(struct page *page) +{ + return folio_detach_private(page_folio(page)); +} + +/* + * There are some parts of the kernel which assume that PMD entries + * are exactly HPAGE_PMD_ORDER. Those should be fixed, but until then, + * limit the maximum allocation order to PMD size. I'm not aware of any + * assumptions about maximum order if THP are disabled, but 8 seems like + * a good order (that's 1MB if you're using 4kB pages) + */ +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +#define MAX_PAGECACHE_ORDER HPAGE_PMD_ORDER +#else +#define MAX_PAGECACHE_ORDER 8 +#endif + +#ifdef CONFIG_NUMA +struct folio *filemap_alloc_folio(gfp_t gfp, unsigned int order); +#else +static inline struct folio *filemap_alloc_folio(gfp_t gfp, unsigned int order) +{ + return folio_alloc(gfp, order); +} +#endif + +static inline struct page *__page_cache_alloc(gfp_t gfp) +{ + return &filemap_alloc_folio(gfp, 0)->page; +} + +static inline struct page *page_cache_alloc(struct address_space *x) +{ + return __page_cache_alloc(mapping_gfp_mask(x)); +} + +static inline gfp_t readahead_gfp_mask(struct address_space *x) +{ + return mapping_gfp_mask(x) | __GFP_NORETRY | __GFP_NOWARN; +} + +typedef int filler_t(struct file *, struct folio *); + +pgoff_t page_cache_next_miss(struct address_space *mapping, + pgoff_t index, unsigned long max_scan); +pgoff_t page_cache_prev_miss(struct address_space *mapping, + pgoff_t index, unsigned long max_scan); + +/** + * typedef fgf_t - Flags for getting folios from the page cache. + * + * Most users of the page cache will not need to use these flags; + * there are convenience functions such as filemap_get_folio() and + * filemap_lock_folio(). For users which need more control over exactly + * what is done with the folios, these flags to __filemap_get_folio() + * are available. + * + * * %FGP_ACCESSED - The folio will be marked accessed. + * * %FGP_LOCK - The folio is returned locked. + * * %FGP_CREAT - If no folio is present then a new folio is allocated, + * added to the page cache and the VM's LRU list. The folio is + * returned locked. + * * %FGP_FOR_MMAP - The caller wants to do its own locking dance if the + * folio is already in cache. If the folio was allocated, unlock it + * before returning so the caller can do the same dance. + * * %FGP_WRITE - The folio will be written to by the caller. + * * %FGP_NOFS - __GFP_FS will get cleared in gfp. + * * %FGP_NOWAIT - Don't block on the folio lock. + * * %FGP_STABLE - Wait for the folio to be stable (finished writeback) + * * %FGP_WRITEBEGIN - The flags to use in a filesystem write_begin() + * implementation. + */ +typedef unsigned int __bitwise fgf_t; + +#define FGP_ACCESSED ((__force fgf_t)0x00000001) +#define FGP_LOCK ((__force fgf_t)0x00000002) +#define FGP_CREAT ((__force fgf_t)0x00000004) +#define FGP_WRITE ((__force fgf_t)0x00000008) +#define FGP_NOFS ((__force fgf_t)0x00000010) +#define FGP_NOWAIT ((__force fgf_t)0x00000020) +#define FGP_FOR_MMAP ((__force fgf_t)0x00000040) +#define FGP_STABLE ((__force fgf_t)0x00000080) +#define FGF_GET_ORDER(fgf) (((__force unsigned)fgf) >> 26) /* top 6 bits */ + +#define FGP_WRITEBEGIN (FGP_LOCK | FGP_WRITE | FGP_CREAT | FGP_STABLE) + +/** + * fgf_set_order - Encode a length in the fgf_t flags. + * @size: The suggested size of the folio to create. + * + * The caller of __filemap_get_folio() can use this to suggest a preferred + * size for the folio that is created. If there is already a folio at + * the index, it will be returned, no matter what its size. If a folio + * is freshly created, it may be of a different size than requested + * due to alignment constraints, memory pressure, or the presence of + * other folios at nearby indices. + */ +static inline fgf_t fgf_set_order(size_t size) +{ + unsigned int shift = ilog2(size); + + if (shift <= PAGE_SHIFT) + return 0; + return (__force fgf_t)((shift - PAGE_SHIFT) << 26); +} + +void *filemap_get_entry(struct address_space *mapping, pgoff_t index); +struct folio *__filemap_get_folio(struct address_space *mapping, pgoff_t index, + fgf_t fgp_flags, gfp_t gfp); +struct page *pagecache_get_page(struct address_space *mapping, pgoff_t index, + fgf_t fgp_flags, gfp_t gfp); + +/** + * filemap_get_folio - Find and get a folio. + * @mapping: The address_space to search. + * @index: The page index. + * + * Looks up the page cache entry at @mapping & @index. If a folio is + * present, it is returned with an increased refcount. + * + * Return: A folio or ERR_PTR(-ENOENT) if there is no folio in the cache for + * this index. Will not return a shadow, swap or DAX entry. + */ +static inline struct folio *filemap_get_folio(struct address_space *mapping, + pgoff_t index) +{ + return __filemap_get_folio(mapping, index, 0, 0); +} + +/** + * filemap_lock_folio - Find and lock a folio. + * @mapping: The address_space to search. + * @index: The page index. + * + * Looks up the page cache entry at @mapping & @index. If a folio is + * present, it is returned locked with an increased refcount. + * + * Context: May sleep. + * Return: A folio or ERR_PTR(-ENOENT) if there is no folio in the cache for + * this index. Will not return a shadow, swap or DAX entry. + */ +static inline struct folio *filemap_lock_folio(struct address_space *mapping, + pgoff_t index) +{ + return __filemap_get_folio(mapping, index, FGP_LOCK, 0); +} + +/** + * filemap_grab_folio - grab a folio from the page cache + * @mapping: The address space to search + * @index: The page index + * + * Looks up the page cache entry at @mapping & @index. If no folio is found, + * a new folio is created. The folio is locked, marked as accessed, and + * returned. + * + * Return: A found or created folio. ERR_PTR(-ENOMEM) if no folio is found + * and failed to create a folio. + */ +static inline struct folio *filemap_grab_folio(struct address_space *mapping, + pgoff_t index) +{ + return __filemap_get_folio(mapping, index, + FGP_LOCK | FGP_ACCESSED | FGP_CREAT, + mapping_gfp_mask(mapping)); +} + +/** + * find_get_page - find and get a page reference + * @mapping: the address_space to search + * @offset: the page index + * + * Looks up the page cache slot at @mapping & @offset. If there is a + * page cache page, it is returned with an increased refcount. + * + * Otherwise, %NULL is returned. + */ +static inline struct page *find_get_page(struct address_space *mapping, + pgoff_t offset) +{ + return pagecache_get_page(mapping, offset, 0, 0); +} + +static inline struct page *find_get_page_flags(struct address_space *mapping, + pgoff_t offset, fgf_t fgp_flags) +{ + return pagecache_get_page(mapping, offset, fgp_flags, 0); +} + +/** + * find_lock_page - locate, pin and lock a pagecache page + * @mapping: the address_space to search + * @index: the page index + * + * Looks up the page cache entry at @mapping & @index. If there is a + * page cache page, it is returned locked and with an increased + * refcount. + * + * Context: May sleep. + * Return: A struct page or %NULL if there is no page in the cache for this + * index. + */ +static inline struct page *find_lock_page(struct address_space *mapping, + pgoff_t index) +{ + return pagecache_get_page(mapping, index, FGP_LOCK, 0); +} + +/** + * find_or_create_page - locate or add a pagecache page + * @mapping: the page's address_space + * @index: the page's index into the mapping + * @gfp_mask: page allocation mode + * + * Looks up the page cache slot at @mapping & @offset. If there is a + * page cache page, it is returned locked and with an increased + * refcount. + * + * If the page is not present, a new page is allocated using @gfp_mask + * and added to the page cache and the VM's LRU list. The page is + * returned locked and with an increased refcount. + * + * On memory exhaustion, %NULL is returned. + * + * find_or_create_page() may sleep, even if @gfp_flags specifies an + * atomic allocation! + */ +static inline struct page *find_or_create_page(struct address_space *mapping, + pgoff_t index, gfp_t gfp_mask) +{ + return pagecache_get_page(mapping, index, + FGP_LOCK|FGP_ACCESSED|FGP_CREAT, + gfp_mask); +} + +/** + * grab_cache_page_nowait - returns locked page at given index in given cache + * @mapping: target address_space + * @index: the page index + * + * Same as grab_cache_page(), but do not wait if the page is unavailable. + * This is intended for speculative data generators, where the data can + * be regenerated if the page couldn't be grabbed. This routine should + * be safe to call while holding the lock for another page. + * + * Clear __GFP_FS when allocating the page to avoid recursion into the fs + * and deadlock against the caller's locked page. + */ +static inline struct page *grab_cache_page_nowait(struct address_space *mapping, + pgoff_t index) +{ + return pagecache_get_page(mapping, index, + FGP_LOCK|FGP_CREAT|FGP_NOFS|FGP_NOWAIT, + mapping_gfp_mask(mapping)); +} + +#define swapcache_index(folio) __page_file_index(&(folio)->page) + +/** + * folio_index - File index of a folio. + * @folio: The folio. + * + * For a folio which is either in the page cache or the swap cache, + * return its index within the address_space it belongs to. If you know + * the page is definitely in the page cache, you can look at the folio's + * index directly. + * + * Return: The index (offset in units of pages) of a folio in its file. + */ +static inline pgoff_t folio_index(struct folio *folio) +{ + if (unlikely(folio_test_swapcache(folio))) + return swapcache_index(folio); + return folio->index; +} + +/** + * folio_next_index - Get the index of the next folio. + * @folio: The current folio. + * + * Return: The index of the folio which follows this folio in the file. + */ +static inline pgoff_t folio_next_index(struct folio *folio) +{ + return folio->index + folio_nr_pages(folio); +} + +/** + * folio_file_page - The page for a particular index. + * @folio: The folio which contains this index. + * @index: The index we want to look up. + * + * Sometimes after looking up a folio in the page cache, we need to + * obtain the specific page for an index (eg a page fault). + * + * Return: The page containing the file data for this index. + */ +static inline struct page *folio_file_page(struct folio *folio, pgoff_t index) +{ + /* HugeTLBfs indexes the page cache in units of hpage_size */ + if (folio_test_hugetlb(folio)) + return &folio->page; + return folio_page(folio, index & (folio_nr_pages(folio) - 1)); +} + +/** + * folio_contains - Does this folio contain this index? + * @folio: The folio. + * @index: The page index within the file. + * + * Context: The caller should have the page locked in order to prevent + * (eg) shmem from moving the page between the page cache and swap cache + * and changing its index in the middle of the operation. + * Return: true or false. + */ +static inline bool folio_contains(struct folio *folio, pgoff_t index) +{ + /* HugeTLBfs indexes the page cache in units of hpage_size */ + if (folio_test_hugetlb(folio)) + return folio->index == index; + return index - folio_index(folio) < folio_nr_pages(folio); +} + +/* + * Given the page we found in the page cache, return the page corresponding + * to this index in the file + */ +static inline struct page *find_subpage(struct page *head, pgoff_t index) +{ + /* HugeTLBfs wants the head page regardless */ + if (PageHuge(head)) + return head; + + return head + (index & (thp_nr_pages(head) - 1)); +} + +unsigned filemap_get_folios(struct address_space *mapping, pgoff_t *start, + pgoff_t end, struct folio_batch *fbatch); +unsigned filemap_get_folios_contig(struct address_space *mapping, + pgoff_t *start, pgoff_t end, struct folio_batch *fbatch); +unsigned filemap_get_folios_tag(struct address_space *mapping, pgoff_t *start, + pgoff_t end, xa_mark_t tag, struct folio_batch *fbatch); + +struct page *grab_cache_page_write_begin(struct address_space *mapping, + pgoff_t index); + +/* + * Returns locked page at given index in given cache, creating it if needed. + */ +static inline struct page *grab_cache_page(struct address_space *mapping, + pgoff_t index) +{ + return find_or_create_page(mapping, index, mapping_gfp_mask(mapping)); +} + +struct folio *read_cache_folio(struct address_space *, pgoff_t index, + filler_t *filler, struct file *file); +struct folio *mapping_read_folio_gfp(struct address_space *, pgoff_t index, + gfp_t flags); +struct page *read_cache_page(struct address_space *, pgoff_t index, + filler_t *filler, struct file *file); +extern struct page * read_cache_page_gfp(struct address_space *mapping, + pgoff_t index, gfp_t gfp_mask); + +static inline struct page *read_mapping_page(struct address_space *mapping, + pgoff_t index, struct file *file) +{ + return read_cache_page(mapping, index, NULL, file); +} + +static inline struct folio *read_mapping_folio(struct address_space *mapping, + pgoff_t index, struct file *file) +{ + return read_cache_folio(mapping, index, NULL, file); +} + +/* + * Get index of the page within radix-tree (but not for hugetlb pages). + * (TODO: remove once hugetlb pages will have ->index in PAGE_SIZE) + */ +static inline pgoff_t page_to_index(struct page *page) +{ + struct page *head; + + if (likely(!PageTransTail(page))) + return page->index; + + head = compound_head(page); + /* + * We don't initialize ->index for tail pages: calculate based on + * head page + */ + return head->index + page - head; +} + +extern pgoff_t hugetlb_basepage_index(struct page *page); + +/* + * Get the offset in PAGE_SIZE (even for hugetlb pages). + * (TODO: hugetlb pages should have ->index in PAGE_SIZE) + */ +static inline pgoff_t page_to_pgoff(struct page *page) +{ + if (unlikely(PageHuge(page))) + return hugetlb_basepage_index(page); + return page_to_index(page); +} + +/* + * Return byte-offset into filesystem object for page. + */ +static inline loff_t page_offset(struct page *page) +{ + return ((loff_t)page->index) << PAGE_SHIFT; +} + +static inline loff_t page_file_offset(struct page *page) +{ + return ((loff_t)page_index(page)) << PAGE_SHIFT; +} + +/** + * folio_pos - Returns the byte position of this folio in its file. + * @folio: The folio. + */ +static inline loff_t folio_pos(struct folio *folio) +{ + return page_offset(&folio->page); +} + +/** + * folio_file_pos - Returns the byte position of this folio in its file. + * @folio: The folio. + * + * This differs from folio_pos() for folios which belong to a swap file. + * NFS is the only filesystem today which needs to use folio_file_pos(). + */ +static inline loff_t folio_file_pos(struct folio *folio) +{ + return page_file_offset(&folio->page); +} + +/* + * Get the offset in PAGE_SIZE (even for hugetlb folios). + * (TODO: hugetlb folios should have ->index in PAGE_SIZE) + */ +static inline pgoff_t folio_pgoff(struct folio *folio) +{ + if (unlikely(folio_test_hugetlb(folio))) + return hugetlb_basepage_index(&folio->page); + return folio->index; +} + +extern pgoff_t linear_hugepage_index(struct vm_area_struct *vma, + unsigned long address); + +static inline pgoff_t linear_page_index(struct vm_area_struct *vma, + unsigned long address) +{ + pgoff_t pgoff; + if (unlikely(is_vm_hugetlb_page(vma))) + return linear_hugepage_index(vma, address); + pgoff = (address - vma->vm_start) >> PAGE_SHIFT; + pgoff += vma->vm_pgoff; + return pgoff; +} + +struct wait_page_key { + struct folio *folio; + int bit_nr; + int page_match; +}; + +struct wait_page_queue { + struct folio *folio; + int bit_nr; + wait_queue_entry_t wait; +}; + +static inline bool wake_page_match(struct wait_page_queue *wait_page, + struct wait_page_key *key) +{ + if (wait_page->folio != key->folio) + return false; + key->page_match = 1; + + if (wait_page->bit_nr != key->bit_nr) + return false; + + return true; +} + +void __folio_lock(struct folio *folio); +int __folio_lock_killable(struct folio *folio); +vm_fault_t __folio_lock_or_retry(struct folio *folio, struct vm_fault *vmf); +void unlock_page(struct page *page); +void folio_unlock(struct folio *folio); + +/** + * folio_trylock() - Attempt to lock a folio. + * @folio: The folio to attempt to lock. + * + * Sometimes it is undesirable to wait for a folio to be unlocked (eg + * when the locks are being taken in the wrong order, or if making + * progress through a batch of folios is more important than processing + * them in order). Usually folio_lock() is the correct function to call. + * + * Context: Any context. + * Return: Whether the lock was successfully acquired. + */ +static inline bool folio_trylock(struct folio *folio) +{ + return likely(!test_and_set_bit_lock(PG_locked, folio_flags(folio, 0))); +} + +/* + * Return true if the page was successfully locked + */ +static inline int trylock_page(struct page *page) +{ + return folio_trylock(page_folio(page)); +} + +/** + * folio_lock() - Lock this folio. + * @folio: The folio to lock. + * + * The folio lock protects against many things, probably more than it + * should. It is primarily held while a folio is being brought uptodate, + * either from its backing file or from swap. It is also held while a + * folio is being truncated from its address_space, so holding the lock + * is sufficient to keep folio->mapping stable. + * + * The folio lock is also held while write() is modifying the page to + * provide POSIX atomicity guarantees (as long as the write does not + * cross a page boundary). Other modifications to the data in the folio + * do not hold the folio lock and can race with writes, eg DMA and stores + * to mapped pages. + * + * Context: May sleep. If you need to acquire the locks of two or + * more folios, they must be in order of ascending index, if they are + * in the same address_space. If they are in different address_spaces, + * acquire the lock of the folio which belongs to the address_space which + * has the lowest address in memory first. + */ +static inline void folio_lock(struct folio *folio) +{ + might_sleep(); + if (!folio_trylock(folio)) + __folio_lock(folio); +} + +/** + * lock_page() - Lock the folio containing this page. + * @page: The page to lock. + * + * See folio_lock() for a description of what the lock protects. + * This is a legacy function and new code should probably use folio_lock() + * instead. + * + * Context: May sleep. Pages in the same folio share a lock, so do not + * attempt to lock two pages which share a folio. + */ +static inline void lock_page(struct page *page) +{ + struct folio *folio; + might_sleep(); + + folio = page_folio(page); + if (!folio_trylock(folio)) + __folio_lock(folio); +} + +/** + * folio_lock_killable() - Lock this folio, interruptible by a fatal signal. + * @folio: The folio to lock. + * + * Attempts to lock the folio, like folio_lock(), except that the sleep + * to acquire the lock is interruptible by a fatal signal. + * + * Context: May sleep; see folio_lock(). + * Return: 0 if the lock was acquired; -EINTR if a fatal signal was received. + */ +static inline int folio_lock_killable(struct folio *folio) +{ + might_sleep(); + if (!folio_trylock(folio)) + return __folio_lock_killable(folio); + return 0; +} + +/* + * folio_lock_or_retry - Lock the folio, unless this would block and the + * caller indicated that it can handle a retry. + * + * Return value and mmap_lock implications depend on flags; see + * __folio_lock_or_retry(). + */ +static inline vm_fault_t folio_lock_or_retry(struct folio *folio, + struct vm_fault *vmf) +{ + might_sleep(); + if (!folio_trylock(folio)) + return __folio_lock_or_retry(folio, vmf); + return 0; +} + +/* + * This is exported only for folio_wait_locked/folio_wait_writeback, etc., + * and should not be used directly. + */ +void folio_wait_bit(struct folio *folio, int bit_nr); +int folio_wait_bit_killable(struct folio *folio, int bit_nr); + +/* + * Wait for a folio to be unlocked. + * + * This must be called with the caller "holding" the folio, + * ie with increased folio reference count so that the folio won't + * go away during the wait. + */ +static inline void folio_wait_locked(struct folio *folio) +{ + if (folio_test_locked(folio)) + folio_wait_bit(folio, PG_locked); +} + +static inline int folio_wait_locked_killable(struct folio *folio) +{ + if (!folio_test_locked(folio)) + return 0; + return folio_wait_bit_killable(folio, PG_locked); +} + +static inline void wait_on_page_locked(struct page *page) +{ + folio_wait_locked(page_folio(page)); +} + +void wait_on_page_writeback(struct page *page); +void folio_wait_writeback(struct folio *folio); +int folio_wait_writeback_killable(struct folio *folio); +void end_page_writeback(struct page *page); +void folio_end_writeback(struct folio *folio); +void wait_for_stable_page(struct page *page); +void folio_wait_stable(struct folio *folio); +void __folio_mark_dirty(struct folio *folio, struct address_space *, int warn); +static inline void __set_page_dirty(struct page *page, + struct address_space *mapping, int warn) +{ + __folio_mark_dirty(page_folio(page), mapping, warn); +} +void folio_account_cleaned(struct folio *folio, struct bdi_writeback *wb); +void __folio_cancel_dirty(struct folio *folio); +static inline void folio_cancel_dirty(struct folio *folio) +{ + /* Avoid atomic ops, locking, etc. when not actually needed. */ + if (folio_test_dirty(folio)) + __folio_cancel_dirty(folio); +} +bool folio_clear_dirty_for_io(struct folio *folio); +bool clear_page_dirty_for_io(struct page *page); +void folio_invalidate(struct folio *folio, size_t offset, size_t length); +int __set_page_dirty_nobuffers(struct page *page); +bool noop_dirty_folio(struct address_space *mapping, struct folio *folio); + +#ifdef CONFIG_MIGRATION +int filemap_migrate_folio(struct address_space *mapping, struct folio *dst, + struct folio *src, enum migrate_mode mode); +#else +#define filemap_migrate_folio NULL +#endif +void folio_end_private_2(struct folio *folio); +void folio_wait_private_2(struct folio *folio); +int folio_wait_private_2_killable(struct folio *folio); + +/* + * Add an arbitrary waiter to a page's wait queue + */ +void folio_add_wait_queue(struct folio *folio, wait_queue_entry_t *waiter); + +/* + * Fault in userspace address range. + */ +size_t fault_in_writeable(char __user *uaddr, size_t size); +size_t fault_in_subpage_writeable(char __user *uaddr, size_t size); +size_t fault_in_safe_writeable(const char __user *uaddr, size_t size); +size_t fault_in_readable(const char __user *uaddr, size_t size); + +int add_to_page_cache_lru(struct page *page, struct address_space *mapping, + pgoff_t index, gfp_t gfp); +int filemap_add_folio(struct address_space *mapping, struct folio *folio, + pgoff_t index, gfp_t gfp); +void filemap_remove_folio(struct folio *folio); +void __filemap_remove_folio(struct folio *folio, void *shadow); +void replace_page_cache_folio(struct folio *old, struct folio *new); +void delete_from_page_cache_batch(struct address_space *mapping, + struct folio_batch *fbatch); +bool filemap_release_folio(struct folio *folio, gfp_t gfp); +loff_t mapping_seek_hole_data(struct address_space *, loff_t start, loff_t end, + int whence); + +/* Must be non-static for BPF error injection */ +int __filemap_add_folio(struct address_space *mapping, struct folio *folio, + pgoff_t index, gfp_t gfp, void **shadowp); + +bool filemap_range_has_writeback(struct address_space *mapping, + loff_t start_byte, loff_t end_byte); + +/** + * filemap_range_needs_writeback - check if range potentially needs writeback + * @mapping: address space within which to check + * @start_byte: offset in bytes where the range starts + * @end_byte: offset in bytes where the range ends (inclusive) + * + * Find at least one page in the range supplied, usually used to check if + * direct writing in this range will trigger a writeback. Used by O_DIRECT + * read/write with IOCB_NOWAIT, to see if the caller needs to do + * filemap_write_and_wait_range() before proceeding. + * + * Return: %true if the caller should do filemap_write_and_wait_range() before + * doing O_DIRECT to a page in this range, %false otherwise. + */ +static inline bool filemap_range_needs_writeback(struct address_space *mapping, + loff_t start_byte, + loff_t end_byte) +{ + if (!mapping->nrpages) + return false; + if (!mapping_tagged(mapping, PAGECACHE_TAG_DIRTY) && + !mapping_tagged(mapping, PAGECACHE_TAG_WRITEBACK)) + return false; + return filemap_range_has_writeback(mapping, start_byte, end_byte); +} + +/** + * struct readahead_control - Describes a readahead request. + * + * A readahead request is for consecutive pages. Filesystems which + * implement the ->readahead method should call readahead_page() or + * readahead_page_batch() in a loop and attempt to start I/O against + * each page in the request. + * + * Most of the fields in this struct are private and should be accessed + * by the functions below. + * + * @file: The file, used primarily by network filesystems for authentication. + * May be NULL if invoked internally by the filesystem. + * @mapping: Readahead this filesystem object. + * @ra: File readahead state. May be NULL. + */ +struct readahead_control { + struct file *file; + struct address_space *mapping; + struct file_ra_state *ra; +/* private: use the readahead_* accessors instead */ + pgoff_t _index; + unsigned int _nr_pages; + unsigned int _batch_count; + bool _workingset; + unsigned long _pflags; +}; + +#define DEFINE_READAHEAD(ractl, f, r, m, i) \ + struct readahead_control ractl = { \ + .file = f, \ + .mapping = m, \ + .ra = r, \ + ._index = i, \ + } + +#define VM_READAHEAD_PAGES (SZ_128K / PAGE_SIZE) + +void page_cache_ra_unbounded(struct readahead_control *, + unsigned long nr_to_read, unsigned long lookahead_count); +void page_cache_sync_ra(struct readahead_control *, unsigned long req_count); +void page_cache_async_ra(struct readahead_control *, struct folio *, + unsigned long req_count); +void readahead_expand(struct readahead_control *ractl, + loff_t new_start, size_t new_len); + +/** + * page_cache_sync_readahead - generic file readahead + * @mapping: address_space which holds the pagecache and I/O vectors + * @ra: file_ra_state which holds the readahead state + * @file: Used by the filesystem for authentication. + * @index: Index of first page to be read. + * @req_count: Total number of pages being read by the caller. + * + * page_cache_sync_readahead() should be called when a cache miss happened: + * it will submit the read. The readahead logic may decide to piggyback more + * pages onto the read request if access patterns suggest it will improve + * performance. + */ +static inline +void page_cache_sync_readahead(struct address_space *mapping, + struct file_ra_state *ra, struct file *file, pgoff_t index, + unsigned long req_count) +{ + DEFINE_READAHEAD(ractl, file, ra, mapping, index); + page_cache_sync_ra(&ractl, req_count); +} + +/** + * page_cache_async_readahead - file readahead for marked pages + * @mapping: address_space which holds the pagecache and I/O vectors + * @ra: file_ra_state which holds the readahead state + * @file: Used by the filesystem for authentication. + * @folio: The folio at @index which triggered the readahead call. + * @index: Index of first page to be read. + * @req_count: Total number of pages being read by the caller. + * + * page_cache_async_readahead() should be called when a page is used which + * is marked as PageReadahead; this is a marker to suggest that the application + * has used up enough of the readahead window that we should start pulling in + * more pages. + */ +static inline +void page_cache_async_readahead(struct address_space *mapping, + struct file_ra_state *ra, struct file *file, + struct folio *folio, pgoff_t index, unsigned long req_count) +{ + DEFINE_READAHEAD(ractl, file, ra, mapping, index); + page_cache_async_ra(&ractl, folio, req_count); +} + +static inline struct folio *__readahead_folio(struct readahead_control *ractl) +{ + struct folio *folio; + + BUG_ON(ractl->_batch_count > ractl->_nr_pages); + ractl->_nr_pages -= ractl->_batch_count; + ractl->_index += ractl->_batch_count; + + if (!ractl->_nr_pages) { + ractl->_batch_count = 0; + return NULL; + } + + folio = xa_load(&ractl->mapping->i_pages, ractl->_index); + VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio); + ractl->_batch_count = folio_nr_pages(folio); + + return folio; +} + +/** + * readahead_page - Get the next page to read. + * @ractl: The current readahead request. + * + * Context: The page is locked and has an elevated refcount. The caller + * should decreases the refcount once the page has been submitted for I/O + * and unlock the page once all I/O to that page has completed. + * Return: A pointer to the next page, or %NULL if we are done. + */ +static inline struct page *readahead_page(struct readahead_control *ractl) +{ + struct folio *folio = __readahead_folio(ractl); + + return &folio->page; +} + +/** + * readahead_folio - Get the next folio to read. + * @ractl: The current readahead request. + * + * Context: The folio is locked. The caller should unlock the folio once + * all I/O to that folio has completed. + * Return: A pointer to the next folio, or %NULL if we are done. + */ +static inline struct folio *readahead_folio(struct readahead_control *ractl) +{ + struct folio *folio = __readahead_folio(ractl); + + if (folio) + folio_put(folio); + return folio; +} + +static inline unsigned int __readahead_batch(struct readahead_control *rac, + struct page **array, unsigned int array_sz) +{ + unsigned int i = 0; + XA_STATE(xas, &rac->mapping->i_pages, 0); + struct page *page; + + BUG_ON(rac->_batch_count > rac->_nr_pages); + rac->_nr_pages -= rac->_batch_count; + rac->_index += rac->_batch_count; + rac->_batch_count = 0; + + xas_set(&xas, rac->_index); + rcu_read_lock(); + xas_for_each(&xas, page, rac->_index + rac->_nr_pages - 1) { + if (xas_retry(&xas, page)) + continue; + VM_BUG_ON_PAGE(!PageLocked(page), page); + VM_BUG_ON_PAGE(PageTail(page), page); + array[i++] = page; + rac->_batch_count += thp_nr_pages(page); + if (i == array_sz) + break; + } + rcu_read_unlock(); + + return i; +} + +/** + * readahead_page_batch - Get a batch of pages to read. + * @rac: The current readahead request. + * @array: An array of pointers to struct page. + * + * Context: The pages are locked and have an elevated refcount. The caller + * should decreases the refcount once the page has been submitted for I/O + * and unlock the page once all I/O to that page has completed. + * Return: The number of pages placed in the array. 0 indicates the request + * is complete. + */ +#define readahead_page_batch(rac, array) \ + __readahead_batch(rac, array, ARRAY_SIZE(array)) + +/** + * readahead_pos - The byte offset into the file of this readahead request. + * @rac: The readahead request. + */ +static inline loff_t readahead_pos(struct readahead_control *rac) +{ + return (loff_t)rac->_index * PAGE_SIZE; +} + +/** + * readahead_length - The number of bytes in this readahead request. + * @rac: The readahead request. + */ +static inline size_t readahead_length(struct readahead_control *rac) +{ + return rac->_nr_pages * PAGE_SIZE; +} + +/** + * readahead_index - The index of the first page in this readahead request. + * @rac: The readahead request. + */ +static inline pgoff_t readahead_index(struct readahead_control *rac) +{ + return rac->_index; +} + +/** + * readahead_count - The number of pages in this readahead request. + * @rac: The readahead request. + */ +static inline unsigned int readahead_count(struct readahead_control *rac) +{ + return rac->_nr_pages; +} + +/** + * readahead_batch_length - The number of bytes in the current batch. + * @rac: The readahead request. + */ +static inline size_t readahead_batch_length(struct readahead_control *rac) +{ + return rac->_batch_count * PAGE_SIZE; +} + +static inline unsigned long dir_pages(struct inode *inode) +{ + return (unsigned long)(inode->i_size + PAGE_SIZE - 1) >> + PAGE_SHIFT; +} + +/** + * folio_mkwrite_check_truncate - check if folio was truncated + * @folio: the folio to check + * @inode: the inode to check the folio against + * + * Return: the number of bytes in the folio up to EOF, + * or -EFAULT if the folio was truncated. + */ +static inline ssize_t folio_mkwrite_check_truncate(struct folio *folio, + struct inode *inode) +{ + loff_t size = i_size_read(inode); + pgoff_t index = size >> PAGE_SHIFT; + size_t offset = offset_in_folio(folio, size); + + if (!folio->mapping) + return -EFAULT; + + /* folio is wholly inside EOF */ + if (folio_next_index(folio) - 1 < index) + return folio_size(folio); + /* folio is wholly past EOF */ + if (folio->index > index || !offset) + return -EFAULT; + /* folio is partially inside EOF */ + return offset; +} + +/** + * page_mkwrite_check_truncate - check if page was truncated + * @page: the page to check + * @inode: the inode to check the page against + * + * Returns the number of bytes in the page up to EOF, + * or -EFAULT if the page was truncated. + */ +static inline int page_mkwrite_check_truncate(struct page *page, + struct inode *inode) +{ + loff_t size = i_size_read(inode); + pgoff_t index = size >> PAGE_SHIFT; + int offset = offset_in_page(size); + + if (page->mapping != inode->i_mapping) + return -EFAULT; + + /* page is wholly inside EOF */ + if (page->index < index) + return PAGE_SIZE; + /* page is wholly past EOF */ + if (page->index > index || !offset) + return -EFAULT; + /* page is partially inside EOF */ + return offset; +} + +/** + * i_blocks_per_folio - How many blocks fit in this folio. + * @inode: The inode which contains the blocks. + * @folio: The folio. + * + * If the block size is larger than the size of this folio, return zero. + * + * Context: The caller should hold a refcount on the folio to prevent it + * from being split. + * Return: The number of filesystem blocks covered by this folio. + */ +static inline +unsigned int i_blocks_per_folio(struct inode *inode, struct folio *folio) +{ + return folio_size(folio) >> inode->i_blkbits; +} + +static inline +unsigned int i_blocks_per_page(struct inode *inode, struct page *page) +{ + return i_blocks_per_folio(inode, page_folio(page)); +} +#endif /* _LINUX_PAGEMAP_H */ |