EXT_LAST_EXTENT
nex = EXT_LAST_EXTENT(eh);
if (nearex != EXT_LAST_EXTENT(eh)) {
while (nearex < EXT_LAST_EXTENT(eh)) {
if (nearex + 1 < EXT_LAST_EXTENT(eh)) {
len = (EXT_LAST_EXTENT(eh) - nearex - 1) *
ex = EXT_LAST_EXTENT(eh);