f2fs: Convert f2fs to read_folio

This is a "weak" conversion which converts straight back to using pages.
A full conversion should be performed at some point, hopefully by
someone familiar with the filesystem.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

fs/f2fs/data.c

@@ -2372,8 +2372,9 @@ static int f2fs_mpage_readpages(struct inode *inode,
 	return ret;
 }
 
-static int f2fs_read_data_page(struct file *file, struct page *page)
+static int f2fs_read_data_folio(struct file *file, struct folio *folio)
 {
+	struct page *page = &folio->page;
 	struct inode *inode = page_file_mapping(page)->host;
 	int ret = -EAGAIN;
 
@@ -3935,7 +3936,7 @@ static void f2fs_swap_deactivate(struct file *file)
 #endif
 
 const struct address_space_operations f2fs_dblock_aops = {
-	.readpage	= f2fs_read_data_page,
+	.read_folio	= f2fs_read_data_folio,
 	.readahead	= f2fs_readahead,
 	.writepage	= f2fs_write_data_page,
 	.writepages	= f2fs_write_data_pages,