i_ffs2_size
lastlbn = lblkno(fs, ip->i_ffs2_size);
ip->i_ffs2_size = lblktosize(fs, nb + 1);
uvm_vnp_setsize(vp, ip->i_ffs2_size);
if (nb != 0 && ip->i_ffs2_size >= lblktosize(fs, lbn + 1)) {
osize = fragroundup(fs, blkoff(fs, ip->i_ffs2_size));
if (ip->i_ffs2_size < lblktosize(fs, lbn + 1))
lastlbn = lblkno(fs, ip->i_ffs2_size);
if (nb != 0 && ip->i_ffs2_size >= lblktosize(fs, lbn + 1)) {
osize = fragroundup(fs, blkoff(fs, ip->i_ffs2_size));
if (ip->i_ffs2_size < lblktosize(fs, lbn + 1))