diff options
Diffstat (limited to 'include/linux/pagemap.h')
| -rw-r--r-- | include/linux/pagemap.h | 68 |
1 files changed, 56 insertions, 12 deletions
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index d1f4eff605ad..c3afd3242b54 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -54,7 +54,8 @@ static inline void mapping_set_error(struct address_space *mapping, int error) __filemap_set_wb_err(mapping, error); /* Record it in superblock */ - errseq_set(&mapping->host->i_sb->s_wb_err, error); + 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) @@ -278,6 +279,7 @@ pgoff_t page_cache_prev_miss(struct address_space *mapping, #define FGP_NOFS 0x00000010 #define FGP_NOWAIT 0x00000020 #define FGP_FOR_MMAP 0x00000040 +#define FGP_HEAD 0x00000080 struct page *pagecache_get_page(struct address_space *mapping, pgoff_t offset, int fgp_flags, gfp_t cache_gfp_mask); @@ -309,18 +311,37 @@ static inline struct page *find_get_page_flags(struct address_space *mapping, * @mapping: the address_space to search * @offset: the page index * - * Looks up the page cache slot at @mapping & @offset. If there is a + * Looks up the page cache entry at @mapping & @offset. If there is a * page cache page, it is returned locked and with an increased * refcount. * - * Otherwise, %NULL is returned. - * - * find_lock_page() may sleep. + * 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 offset) + pgoff_t index) +{ + return pagecache_get_page(mapping, index, FGP_LOCK, 0); +} + +/** + * find_lock_head - Locate, pin and lock a pagecache page. + * @mapping: The address_space to search. + * @offset: The page index. + * + * Looks up the page cache entry at @mapping & @offset. If there is a + * page cache page, its head page is returned locked and with an increased + * refcount. + * + * Context: May sleep. + * Return: A struct page which is !PageTail, or %NULL if there is no page + * in the cache for this index. + */ +static inline struct page *find_lock_head(struct address_space *mapping, + pgoff_t index) { - return pagecache_get_page(mapping, offset, FGP_LOCK, 0); + return pagecache_get_page(mapping, index, FGP_LOCK | FGP_HEAD, 0); } /** @@ -371,6 +392,15 @@ static inline struct page *grab_cache_page_nowait(struct address_space *mapping, mapping_gfp_mask(mapping)); } +/* Does this page contain this index? */ +static inline bool thp_contains(struct page *head, pgoff_t index) +{ + /* HugeTLBfs indexes the page cache in units of hpage_size */ + if (PageHuge(head)) + return head->index == index; + return page_index(head) == (index & ~(thp_nr_pages(head) - 1UL)); +} + /* * Given the page we found in the page cache, return the page corresponding * to this index in the file @@ -381,11 +411,9 @@ static inline struct page *find_subpage(struct page *head, pgoff_t index) if (PageHuge(head)) return head; - return head + (index & (hpage_nr_pages(head) - 1)); + return head + (index & (thp_nr_pages(head) - 1)); } -struct page *find_get_entry(struct address_space *mapping, pgoff_t offset); -struct page *find_lock_entry(struct address_space *mapping, pgoff_t offset); unsigned find_get_entries(struct address_space *mapping, pgoff_t start, unsigned int nr_entries, struct page **entries, pgoff_t *indices); @@ -773,7 +801,7 @@ static inline struct page *readahead_page(struct readahead_control *rac) page = xa_load(&rac->mapping->i_pages, rac->_index); VM_BUG_ON_PAGE(!PageLocked(page), page); - rac->_batch_count = hpage_nr_pages(page); + rac->_batch_count = thp_nr_pages(page); return page; } @@ -796,7 +824,7 @@ static inline unsigned int __readahead_batch(struct readahead_control *rac, VM_BUG_ON_PAGE(!PageLocked(page), page); VM_BUG_ON_PAGE(PageTail(page), page); array[i++] = page; - rac->_batch_count += hpage_nr_pages(page); + rac->_batch_count += thp_nr_pages(page); /* * The page cache isn't using multi-index entries yet, @@ -899,4 +927,20 @@ static inline int page_mkwrite_check_truncate(struct page *page, return offset; } +/** + * i_blocks_per_page - How many blocks fit in this page. + * @inode: The inode which contains the blocks. + * @page: The page (head page if the page is a THP). + * + * If the block size is larger than the size of this page, return zero. + * + * Context: The caller should hold a refcount on the page to prevent it + * from being split. + * Return: The number of filesystem blocks covered by this page. + */ +static inline +unsigned int i_blocks_per_page(struct inode *inode, struct page *page) +{ + return thp_size(page) >> inode->i_blkbits; +} #endif /* _LINUX_PAGEMAP_H */ |