lfs_newbuf
struct buf *lfs_newbuf(struct lfs *, struct vnode *, daddr_t, size_t, int);
sbp = lfs_newbuf(fs, VTOI(fs->lfs_ivnode)->i_devvp,
newbp = lfs_newbuf(fs, bp->b_vp, bp->b_lblkno,
bp = lfs_newbuf(fs, devvp,
bp = lfs_newbuf(VTOI(vp)->i_lfs, vp, lbn, size, LFS_NB_CLEAN);