f2fs: call redirty_page_for_writepage

This patch replace some general codes with redirty_page_for_writepage, which
can be enabled after consideration on additional procedure like counting dirty
pages appropriately.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 45abd60..b5cd6d1 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -798,10 +798,8 @@
 	 * this page does not have to be written to disk.
 	 */
 	offset = i_size & (PAGE_CACHE_SIZE - 1);
-	if ((page->index >= end_index + 1) || !offset) {
-		inode_dec_dirty_dents(inode);
+	if ((page->index >= end_index + 1) || !offset)
 		goto out;
-	}
 
 	zero_user_segment(page, offset, PAGE_CACHE_SIZE);
 write:
@@ -810,7 +808,6 @@
 
 	/* Dentry blocks are controlled by checkpoint */
 	if (S_ISDIR(inode->i_mode)) {
-		inode_dec_dirty_dents(inode);
 		err = do_write_data_page(page, &fio);
 		goto done;
 	}
@@ -832,15 +829,14 @@
 
 	clear_cold_data(page);
 out:
+	inode_dec_dirty_dents(inode);
 	unlock_page(page);
 	if (need_balance_fs)
 		f2fs_balance_fs(sbi);
 	return 0;
 
 redirty_out:
-	wbc->pages_skipped++;
-	account_page_redirty(page);
-	set_page_dirty(page);
+	redirty_page_for_writepage(wbc, page);
 	return AOP_WRITEPAGE_ACTIVATE;
 }