ulfs_bufio
error = ulfs_bufio(UIO_READ, vp, &dirbuf, sizeof dirbuf, (off_t)0,
error = ulfs_bufio(UIO_WRITE, *vpp, ap->a_target, len, (off_t)0,
int ulfs_bufio(enum uio_rw, struct vnode *, void *, size_t, off_t, int,
error = ulfs_bufio(UIO_READ, ITOV(ip), (void *)dp, MINDIRSIZ,