-/**
- * ntfs_unmap_page - release a page that was mapped using ntfs_map_page()
- * @page: the page to release
- *
- * Unpin, unmap and release a page that was obtained from ntfs_map_page().
- */
-static inline void ntfs_unmap_page(struct page *page)
-{
- kunmap(page);
- page_cache_release(page);
-}
-
-/**
- * ntfs_map_page - map a page into accessible memory, reading it if necessary
- * @mapping: address space for which to obtain the page
- * @index: index into the page cache for @mapping of the page to map
- *
- * Read a page from the page cache of the address space @mapping at position
- * @index, where @index is in units of PAGE_CACHE_SIZE, and not in bytes.
- *
- * If the page is not in memory it is loaded from disk first using the readpage
- * method defined in the address space operations of @mapping and the page is
- * added to the page cache of @mapping in the process.
- *
- * If the page is in high memory it is mapped into memory directly addressible
- * by the kernel.
- *
- * Finally the page count is incremented, thus pinning the page into place.
- *
- * The above means that page_address(page) can be used on all pages obtained
- * with ntfs_map_page() to get the kernel virtual address of the page.
- *
- * When finished with the page, the caller has to call ntfs_unmap_page() to
- * unpin, unmap and release the page.
- *
- * Note this does not grant exclusive access. If such is desired, the caller
- * must provide it independently of the ntfs_{un}map_page() calls by using
- * a {rw_}semaphore or other means of serialization. A spin lock cannot be
- * used as ntfs_map_page() can block.
- *
- * The unlocked and uptodate page is returned on success or an encoded error
- * on failure. Caller has to test for error using the IS_ERR() macro on the
- * return value. If that evaluates to TRUE, the negative error code can be
- * obtained using PTR_ERR() on the return value of ntfs_map_page().
- */
-static inline struct page *ntfs_map_page(struct address_space *mapping,
- unsigned long index)
-{
- struct page *page = read_cache_page(mapping, index,
- (filler_t*)mapping->a_ops->readpage, NULL);
-
- if (!IS_ERR(page)) {
- wait_on_page_locked(page);
- kmap(page);
- if (PageUptodate(page) && !PageError(page))
- return page;
- ntfs_unmap_page(page);
- return ERR_PTR(-EIO);
- }
- return page;
-}
-