580 	int hs = sizeof (hdr);  in pg_write()  local
584 	if (count < hs)  in pg_write()
587 	if (copy_from_user(&hdr, buf, hs))  in pg_write()
594 	if ((count - hs) > PG_MAX_DATA)  in pg_write()
598 		if (count != hs)  in pg_write()
619 	if (copy_from_user(dev->bufptr, buf + hs, count - hs))  in pg_write()
628 	int hs = sizeof (hdr);  in pg_read()  local
633 	if (count < hs)  in pg_read()
650 		if (copy > (count - hs))  in pg_read()
651 			copy = count - hs;  in pg_read()
657 	if (copy_to_user(buf, &hdr, hs))  in pg_read()
660 		if (copy_to_user(buf + hs, dev->bufptr, copy))  in pg_read()
662 	return copy + hs;  in pg_read()