ulfs_getlbns
if ((error = ulfs_getlbns(fs, vp, bn, xap, nump)) != 0)
int ulfs_getlbns(struct lfs *, struct uvnode *, daddr_t, struct indir *, int *);
if ((error = ulfs_getlbns(vp, bn, xap, nump)) != 0)
int ulfs_getlbns(struct vnode *, daddr_t, struct indir *, int *);