f2fs: convert f2fs_write_data_page() to use folio

Convert to use folio, so that we can get rid of 'page->index' to
prepare for removal of 'index' field in structure page [1].

[1] https://lore.kernel.org/all/Zp8fgUSIBGQ1TN0D@casper.infradead.org/

Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Chao Yu <chao@kernel.org>
Reviewed-by: Li Zetao <lizetao1@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/data.c

@@ -2945,22 +2945,23 @@ int f2fs_write_single_data_page(struct folio *folio, int *submitted,
 static int f2fs_write_data_page(struct page *page,
 					struct writeback_control *wbc)
 {
+	struct folio *folio = page_folio(page);
 #ifdef CONFIG_F2FS_FS_COMPRESSION
-	struct inode *inode = page->mapping->host;
+	struct inode *inode = folio->mapping->host;
 
 	if (unlikely(f2fs_cp_error(F2FS_I_SB(inode))))
 		goto out;
 
 	if (f2fs_compressed_file(inode)) {
-		if (f2fs_is_compressed_cluster(inode, page->index)) {
-			redirty_page_for_writepage(wbc, page);
+		if (f2fs_is_compressed_cluster(inode, folio->index)) {
+			folio_redirty_for_writepage(wbc, folio);
 			return AOP_WRITEPAGE_ACTIVATE;
 		}
 	}
 out:
 #endif
 
-	return f2fs_write_single_data_page(page_folio(page), NULL, NULL, NULL,
+	return f2fs_write_single_data_page(folio, NULL, NULL, NULL,
 						wbc, FS_DATA_IO, 0, true);
 }