f2fs: call f2fs_balance_fs for setattr

If inode becomes dirty, we need to check the # of dirty inodes whether or not
further checkpoint would be required.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 578bc7b..5e3e167 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -694,7 +694,6 @@
 			err = f2fs_truncate(inode);
 			if (err)
 				return err;
-			f2fs_balance_fs(F2FS_I_SB(inode), true);
 		} else {
 			/*
 			 * do not trim all blocks after i_size if target size is
@@ -723,6 +722,10 @@
 	}
 
 	f2fs_mark_inode_dirty_sync(inode);
+
+	/* inode change will produce dirty node pages flushed by checkpoint */
+	f2fs_balance_fs(F2FS_I_SB(inode), true);
+
 	return err;
 }