cdrom.c

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	return ret;
}

static int cdrom_media_changed(kdev_t dev)
{
	struct cdrom_device_info *cdi = cdrom_find_device(dev);
	/* This talks to the VFS, which doesn't like errors - just 1 or 0.  
	 * Returning "0" is always safe (media hasn't been changed). Do that 
	 * if the low-level cdrom driver dosn't support media changed. */ 
	if (cdi == NULL || cdi->ops->media_changed == NULL)
		return 0;
	if (!CDROM_CAN(CDC_MEDIA_CHANGED))
		return 0;
	return media_changed(cdi, 0);
}

/* badly broken, I know. Is due for a fixup anytime. */
void cdrom_count_tracks(struct cdrom_device_info *cdi, tracktype* tracks)
{
	struct cdrom_tochdr header;
	struct cdrom_tocentry entry;
	int ret, i;
	tracks->data=0;
	tracks->audio=0;
	tracks->cdi=0;
	tracks->xa=0;
	tracks->error=0;
	cdinfo(CD_COUNT_TRACKS, "entering cdrom_count_tracks\n"); 
        if (!CDROM_CAN(CDC_PLAY_AUDIO)) { 
                tracks->error=CDS_NO_INFO;
                return;
        }        
	/* Grab the TOC header so we can see how many tracks there are */
	if ((ret = cdi->ops->audio_ioctl(cdi, CDROMREADTOCHDR, &header))) {
		if (ret == -ENOMEDIUM)
			tracks->error = CDS_NO_DISC;
		else
			tracks->error = CDS_NO_INFO;
		return;
	}	
	/* check what type of tracks are on this disc */
	entry.cdte_format = CDROM_MSF;
	for (i = header.cdth_trk0; i <= header.cdth_trk1; i++) {
		entry.cdte_track  = i;
		if (cdi->ops->audio_ioctl(cdi, CDROMREADTOCENTRY, &entry)) {
			tracks->error=CDS_NO_INFO;
			return;
		}	
		if (entry.cdte_ctrl & CDROM_DATA_TRACK) {
		    if (entry.cdte_format == 0x10)
			tracks->cdi++;
		    else if (entry.cdte_format == 0x20) 
			tracks->xa++;
		    else
			tracks->data++;
		} else
		    tracks->audio++;
		cdinfo(CD_COUNT_TRACKS, "track %d: format=%d, ctrl=%d\n",
		       i, entry.cdte_format, entry.cdte_ctrl);
	}	
	cdinfo(CD_COUNT_TRACKS, "disc has %d tracks: %d=audio %d=data %d=Cd-I %d=XA\n", 
		header.cdth_trk1, tracks->audio, tracks->data, 
		tracks->cdi, tracks->xa);
}	

/* Requests to the low-level drivers will /always/ be done in the
   following format convention:

   CDROM_LBA: all data-related requests.
   CDROM_MSF: all audio-related requests.

   However, a low-level implementation is allowed to refuse this
   request, and return information in its own favorite format.

   It doesn't make sense /at all/ to ask for a play_audio in LBA
   format, or ask for multi-session info in MSF format. However, for
   backward compatibility these format requests will be satisfied, but
   the requests to the low-level drivers will be sanitized in the more
   meaningful format indicated above.
 */

static
void sanitize_format(union cdrom_addr *addr,
		     u_char * curr, u_char requested)
{
	if (*curr == requested)
		return;                 /* nothing to be done! */
	if (requested == CDROM_LBA) {
		addr->lba = (int) addr->msf.frame +
			75 * (addr->msf.second - 2 + 60 * addr->msf.minute);
	} else {                        /* CDROM_MSF */
		int lba = addr->lba;
		addr->msf.frame = lba % 75;
		lba /= 75;
		lba += 2;
		addr->msf.second = lba % 60;
		addr->msf.minute = lba / 60;
	}
	*curr = requested;
}

void init_cdrom_command(struct cdrom_generic_command *cgc, void *buf, int len,
			int type)
{
	memset(cgc, 0, sizeof(struct cdrom_generic_command));
	if (buf)
		memset(buf, 0, len);
	cgc->buffer = (char *) buf;
	cgc->buflen = len;
	cgc->data_direction = type;
	cgc->timeout = 5*HZ;
}

/* DVD handling */

#define copy_key(dest,src)	memcpy((dest), (src), sizeof(dvd_key))
#define copy_chal(dest,src)	memcpy((dest), (src), sizeof(dvd_challenge))

static void setup_report_key(struct cdrom_generic_command *cgc, unsigned agid, unsigned type)
{
	cgc->cmd[0] = GPCMD_REPORT_KEY;
	cgc->cmd[10] = type | (agid << 6);
	switch (type) {
		case 0: case 8: case 5: {
			cgc->buflen = 8;
			break;
		}
		case 1: {
			cgc->buflen = 16;
			break;
		}
		case 2: case 4: {
			cgc->buflen = 12;
			break;
		}
	}
	cgc->cmd[9] = cgc->buflen;
	cgc->data_direction = CGC_DATA_READ;
}

static void setup_send_key(struct cdrom_generic_command *cgc, unsigned agid, unsigned type)
{
	cgc->cmd[0] = GPCMD_SEND_KEY;
	cgc->cmd[10] = type | (agid << 6);
	switch (type) {
		case 1: {
			cgc->buflen = 16;
			break;
		}
		case 3: {
			cgc->buflen = 12;
			break;
		}
		case 6: {
			cgc->buflen = 8;
			break;
		}
	}
	cgc->cmd[9] = cgc->buflen;
	cgc->data_direction = CGC_DATA_WRITE;
}

static int dvd_do_auth(struct cdrom_device_info *cdi, dvd_authinfo *ai)
{
	int ret;
	u_char buf[20];
	struct cdrom_generic_command cgc;
	struct cdrom_device_ops *cdo = cdi->ops;
	rpc_state_t rpc_state;

	memset(buf, 0, sizeof(buf));
	init_cdrom_command(&cgc, buf, 0, CGC_DATA_READ);

	switch (ai->type) {
	/* LU data send */
	case DVD_LU_SEND_AGID:
		cdinfo(CD_DVD, "entering DVD_LU_SEND_AGID\n"); 
		setup_report_key(&cgc, ai->lsa.agid, 0);

		if ((ret = cdo->generic_packet(cdi, &cgc)))
			return ret;

		ai->lsa.agid = buf[7] >> 6;
		/* Returning data, let host change state */
		break;

	case DVD_LU_SEND_KEY1:
		cdinfo(CD_DVD, "entering DVD_LU_SEND_KEY1\n"); 
		setup_report_key(&cgc, ai->lsk.agid, 2);

		if ((ret = cdo->generic_packet(cdi, &cgc)))
			return ret;

		copy_key(ai->lsk.key, &buf[4]);
		/* Returning data, let host change state */
		break;

	case DVD_LU_SEND_CHALLENGE:
		cdinfo(CD_DVD, "entering DVD_LU_SEND_CHALLENGE\n"); 
		setup_report_key(&cgc, ai->lsc.agid, 1);

		if ((ret = cdo->generic_packet(cdi, &cgc)))
			return ret;

		copy_chal(ai->lsc.chal, &buf[4]);
		/* Returning data, let host change state */
		break;

	/* Post-auth key */
	case DVD_LU_SEND_TITLE_KEY:
		cdinfo(CD_DVD, "entering DVD_LU_SEND_TITLE_KEY\n"); 
		setup_report_key(&cgc, ai->lstk.agid, 4);
		cgc.cmd[5] = ai->lstk.lba;
		cgc.cmd[4] = ai->lstk.lba >> 8;
		cgc.cmd[3] = ai->lstk.lba >> 16;
		cgc.cmd[2] = ai->lstk.lba >> 24;

		if ((ret = cdo->generic_packet(cdi, &cgc)))
			return ret;

		ai->lstk.cpm = (buf[4] >> 7) & 1;
		ai->lstk.cp_sec = (buf[4] >> 6) & 1;
		ai->lstk.cgms = (buf[4] >> 4) & 3;
		copy_key(ai->lstk.title_key, &buf[5]);
		/* Returning data, let host change state */
		break;

	case DVD_LU_SEND_ASF:
		cdinfo(CD_DVD, "entering DVD_LU_SEND_ASF\n"); 
		setup_report_key(&cgc, ai->lsasf.agid, 5);
		
		if ((ret = cdo->generic_packet(cdi, &cgc)))
			return ret;

		ai->lsasf.asf = buf[7] & 1;
		break;

	/* LU data receive (LU changes state) */
	case DVD_HOST_SEND_CHALLENGE:
		cdinfo(CD_DVD, "entering DVD_HOST_SEND_CHALLENGE\n"); 
		setup_send_key(&cgc, ai->hsc.agid, 1);
		buf[1] = 0xe;
		copy_chal(&buf[4], ai->hsc.chal);

		if ((ret = cdo->generic_packet(cdi, &cgc)))
			return ret;

		ai->type = DVD_LU_SEND_KEY1;
		break;

	case DVD_HOST_SEND_KEY2:
		cdinfo(CD_DVD, "entering DVD_HOST_SEND_KEY2\n"); 
		setup_send_key(&cgc, ai->hsk.agid, 3);
		buf[1] = 0xa;
		copy_key(&buf[4], ai->hsk.key);

		if ((ret = cdo->generic_packet(cdi, &cgc))) {
			ai->type = DVD_AUTH_FAILURE;
			return ret;
		}
		ai->type = DVD_AUTH_ESTABLISHED;
		break;

	/* Misc */
	case DVD_INVALIDATE_AGID:
		cdinfo(CD_DVD, "entering DVD_INVALIDATE_AGID\n"); 
		setup_report_key(&cgc, ai->lsa.agid, 0x3f);
		if ((ret = cdo->generic_packet(cdi, &cgc)))
			return ret;
		break;

	/* Get region settings */
	case DVD_LU_SEND_RPC_STATE:
		cdinfo(CD_DVD, "entering DVD_LU_SEND_RPC_STATE\n");
		setup_report_key(&cgc, 0, 8);
		memset(&rpc_state, 0, sizeof(rpc_state_t));
		cgc.buffer = (char *) &rpc_state;

		if ((ret = cdo->generic_packet(cdi, &cgc)))
			return ret;

		ai->lrpcs.type = rpc_state.type_code;
		ai->lrpcs.vra = rpc_state.vra;
		ai->lrpcs.ucca = rpc_state.ucca;
		ai->lrpcs.region_mask = rpc_state.region_mask;
		ai->lrpcs.rpc_scheme = rpc_state.rpc_scheme;
		break;

	/* Set region settings */
	case DVD_HOST_SEND_RPC_STATE:
		cdinfo(CD_DVD, "entering DVD_HOST_SEND_RPC_STATE\n");
		setup_send_key(&cgc, 0, 6);
		buf[1] = 6;
		buf[4] = ai->hrpcs.pdrc;

		if ((ret = cdo->generic_packet(cdi, &cgc)))
			return ret;
		break;

	default:
		cdinfo(CD_WARNING, "Invalid DVD key ioctl (%d)\n", ai->type);
		return -ENOTTY;
	}

	return 0;
}

static int dvd_read_physical(struct cdrom_device_info *cdi, dvd_struct *s)
{
	int ret, i;
	u_char buf[4 + 4 * 20], *base;
	struct dvd_layer *layer;
	struct cdrom_generic_command cgc;
	struct cdrom_device_ops *cdo = cdi->ops;

	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
	cgc.cmd[0] = GPCMD_READ_DVD_STRUCTURE;
	cgc.cmd[6] = s->physical.layer_num;
	cgc.cmd[7] = s->type;
	cgc.cmd[9] = cgc.buflen & 0xff;

	if ((ret = cdo->generic_packet(cdi, &cgc)))
		return ret;

	base = &buf[4];
	layer = &s->physical.layer[0];

	/* place the data... really ugly, but at least we won't have to
	   worry about endianess in userspace or here. */
	for (i = 0; i < 4; ++i, base += 20, ++layer) {
		memset(layer, 0, sizeof(*layer));
		layer->book_version = base[0] & 0xf;
		layer->book_type = base[0] >> 4;
		layer->min_rate = base[1] & 0xf;
		layer->disc_size = base[1] >> 4;
		layer->layer_type = base[2] & 0xf;
		layer->track_path = (base[2] >> 4) & 1;
		layer->nlayers = (base[2] >> 5) & 3;
		layer->track_density = base[3] & 0xf;
		layer->linear_density = base[3] >> 4;
		layer->start_sector = base[5] << 16 | base[6] << 8 | base[7];
		layer->end_sector = base[9] << 16 | base[10] << 8 | base[11];
		layer->end_sector_l0 = base[13] << 16 | base[14] << 8 | base[15];
		layer->bca = base[16] >> 7;
	}

	return 0;
}

static int dvd_read_copyright(struct cdrom_device_info *cdi, dvd_struct *s)
{
	int ret;
	u_char buf[8];
	struct cdrom_generic_command cgc;
	struct cdrom_device_ops *cdo = cdi->ops;

	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
	cgc.cmd[0] = GPCMD_READ_DVD_STRUCTURE;
	cgc.cmd[6] = s->copyright.layer_num;
	cgc.cmd[7] = s->type;
	cgc.cmd[8] = cgc.buflen >> 8;
	cgc.cmd[9] = cgc.buflen & 0xff;

	if ((ret = cdo->generic_packet(cdi, &cgc)))
		return ret;

	s->copyright.cpst = buf[4];
	s->copyright.rmi = buf[5];

	return 0;
}

static int dvd_read_disckey(struct cdrom_device_info *cdi, dvd_struct *s)
{
	int ret, size;
	u_char *buf;
	struct cdrom_generic_command cgc;
	struct cdrom_device_ops *cdo = cdi->ops;

	size = sizeof(s->disckey.value) + 4;

	if ((buf = (u_char *) kmalloc(size, GFP_KERNEL)) == NULL)
		return -ENOMEM;

	init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
	cgc.cmd[0] = GPCMD_READ_DVD_STRUCTURE;
	cgc.cmd[7] = s->type;
	cgc.cmd[8] = size >> 8;
	cgc.cmd[9] = size & 0xff;
	cgc.cmd[10] = s->disckey.agid << 6;

	if (!(ret = cdo->generic_packet(cdi, &cgc)))
		memcpy(s->disckey.value, &buf[4], sizeof(s->disckey.value));

	kfree(buf);
	return ret;
}

static int dvd_read_bca(struct cdrom_device_info *cdi, dvd_struct *s)
{
	int ret;
	u_char buf[4 + 188];
	struct cdrom_generic_command cgc;
	struct cdrom_device_ops *cdo = cdi->ops;

	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
	cgc.cmd[0] = GPCMD_READ_DVD_STRUCTURE;
	cgc.cmd[7] = s->type;
	cgc.cmd[9] = cgc.buflen = 0xff;

	if ((ret = cdo->generic_packet(cdi, &cgc)))
		return ret;

	s->bca.len = buf[0] << 8 | buf[1];
	if (s->bca.len < 12 || s->bca.len > 188) {
		cdinfo(CD_WARNING, "Received invalid BCA length (%d)\n", s->bca.len);
		return -EIO;
	}
	memcpy(s->bca.value, &buf[4], s->bca.len);

	return 0;
}

static int dvd_read_manufact(struct cdrom_device_info *cdi, dvd_struct *s)
{
	int ret = 0, size;
	u_char *buf;
	struct cdrom_generic_command cgc;
	struct cdrom_device_ops *cdo = cdi->ops;

	size = sizeof(s->manufact.value) + 4;