WINDOW_MASK
ret.x[0] = readb(iomapadr + (ofs & WINDOW_MASK));
if (len > (WINDOW_LENGTH - (from & WINDOW_MASK)))
thislen = WINDOW_LENGTH-(from & WINDOW_MASK);
memcpy_fromio(to, iomapadr + (from & WINDOW_MASK), thislen);
writeb(d.x[0], iomapadr + (adr & WINDOW_MASK));
if (len > (WINDOW_LENGTH - (to & WINDOW_MASK)))
thislen = WINDOW_LENGTH-(to & WINDOW_MASK);
memcpy_toio(iomapadr + (to & WINDOW_MASK), from, thislen);