i_e2fs_last_blk
if ( ip->i_e2fs_last_blk && lbn == ip->i_e2fs_last_lblk + 1) {
return ip->i_e2fs_last_blk + 1;
ip->i_e2fs_last_blk = newb;
ip->i_e2fs_last_blk = newb;
ip->i_e2fs_last_blk = newb;
ip->i_e2fs_last_blk = newb;
ip->i_e2fs_last_blk = 0;