loff_t_to_s64
*l_offset = loff_t_to_s64(fl->fl_start);
*l_len = loff_t_to_s64(fl->fl_end - fl->fl_start + 1);
start = loff_t_to_s64(fl->fl_start);
len = loff_t_to_s64(fl->fl_end - fl->fl_start + 1);