cdrom.c

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	if (CDROM_CAN(CDC_GENERIC_PACKET)) {
		ret = mmc_ioctl(cdi, cmd, arg);
		if (ret != -ENOTTY) {
			return ret;
		}
	}

	/* note: most of the cdinfo() calls are commented out here,
	   because they fill up the sys log when CD players poll
	   the drive. */
	switch (cmd) {
	case CDROMSUBCHNL: {
		struct cdrom_subchnl q;
		u_char requested, back;
		if (!CDROM_CAN(CDC_PLAY_AUDIO))
			return -ENOSYS;
		/* cdinfo(CD_DO_IOCTL,"entering CDROMSUBCHNL\n");*/ 
		IOCTL_IN(arg, struct cdrom_subchnl, q);
		requested = q.cdsc_format;
		if (!((requested == CDROM_MSF) ||
		      (requested == CDROM_LBA)))
			return -EINVAL;
		q.cdsc_format = CDROM_MSF;
		if ((ret=cdo->audio_ioctl(cdi, cmd, &q)))
			return ret;
		back = q.cdsc_format; /* local copy */
		sanitize_format(&q.cdsc_absaddr, &back, requested);
		sanitize_format(&q.cdsc_reladdr, &q.cdsc_format, requested);
		IOCTL_OUT(arg, struct cdrom_subchnl, q);
		/* cdinfo(CD_DO_IOCTL, "CDROMSUBCHNL successful\n"); */ 
		return 0;
		}
	case CDROMREADTOCHDR: {
		struct cdrom_tochdr header;
		if (!CDROM_CAN(CDC_PLAY_AUDIO))
			return -ENOSYS;
		/* cdinfo(CD_DO_IOCTL, "entering CDROMREADTOCHDR\n"); */ 
		IOCTL_IN(arg, struct cdrom_tochdr, header);
		if ((ret=cdo->audio_ioctl(cdi, cmd, &header)))
			return ret;
		IOCTL_OUT(arg, struct cdrom_tochdr, header);
		/* cdinfo(CD_DO_IOCTL, "CDROMREADTOCHDR successful\n"); */ 
		return 0;
		}
	case CDROMREADTOCENTRY: {
		struct cdrom_tocentry entry;
		u_char requested_format;
		if (!CDROM_CAN(CDC_PLAY_AUDIO))
			return -ENOSYS;
		/* cdinfo(CD_DO_IOCTL, "entering CDROMREADTOCENTRY\n"); */ 
		IOCTL_IN(arg, struct cdrom_tocentry, entry);
		requested_format = entry.cdte_format;
		if (!((requested_format == CDROM_MSF) || 
			(requested_format == CDROM_LBA)))
				return -EINVAL;
		/* make interface to low-level uniform */
		entry.cdte_format = CDROM_MSF;
		if ((ret=cdo->audio_ioctl(cdi, cmd, &entry)))
			return ret;
		sanitize_format(&entry.cdte_addr,
		&entry.cdte_format, requested_format);
		IOCTL_OUT(arg, struct cdrom_tocentry, entry);
		/* cdinfo(CD_DO_IOCTL, "CDROMREADTOCENTRY successful\n"); */ 
		return 0;
		}
	case CDROMPLAYMSF: {
		struct cdrom_msf msf;
		if (!CDROM_CAN(CDC_PLAY_AUDIO))
			return -ENOSYS;
		cdinfo(CD_DO_IOCTL, "entering CDROMPLAYMSF\n"); 
		IOCTL_IN(arg, struct cdrom_msf, msf);
		return cdo->audio_ioctl(cdi, cmd, &msf);
		}
	case CDROMPLAYTRKIND: {
		struct cdrom_ti ti;
		if (!CDROM_CAN(CDC_PLAY_AUDIO))
			return -ENOSYS;
		cdinfo(CD_DO_IOCTL, "entering CDROMPLAYTRKIND\n"); 
		IOCTL_IN(arg, struct cdrom_ti, ti);
		CHECKAUDIO;
		return cdo->audio_ioctl(cdi, cmd, &ti);
		}
	case CDROMVOLCTRL: {
		struct cdrom_volctrl volume;
		if (!CDROM_CAN(CDC_PLAY_AUDIO))
			return -ENOSYS;
		cdinfo(CD_DO_IOCTL, "entering CDROMVOLCTRL\n"); 
		IOCTL_IN(arg, struct cdrom_volctrl, volume);
		return cdo->audio_ioctl(cdi, cmd, &volume);
		}
	case CDROMVOLREAD: {
		struct cdrom_volctrl volume;
		if (!CDROM_CAN(CDC_PLAY_AUDIO))
			return -ENOSYS;
		cdinfo(CD_DO_IOCTL, "entering CDROMVOLREAD\n"); 
		if ((ret=cdo->audio_ioctl(cdi, cmd, &volume)))
			return ret;
		IOCTL_OUT(arg, struct cdrom_volctrl, volume);
		return 0;
		}
	case CDROMSTART:
	case CDROMSTOP:
	case CDROMPAUSE:
	case CDROMRESUME: {
		if (!CDROM_CAN(CDC_PLAY_AUDIO))
			return -ENOSYS;
		cdinfo(CD_DO_IOCTL, "doing audio ioctl (start/stop/pause/resume)\n"); 
		CHECKAUDIO;
		return cdo->audio_ioctl(cdi, cmd, NULL);
		}
	} /* switch */

	/* do the device specific ioctls */
	if (CDROM_CAN(CDC_IOCTLS))
		return cdo->dev_ioctl(cdi, cmd, arg);
	
	return -ENOSYS;
}

static inline
int msf_to_lba(char m, char s, char f)
{
	return (((m * CD_SECS) + s) * CD_FRAMES + f) - CD_MSF_OFFSET;
}

/*
 * Required when we need to use READ_10 to issue other than 2048 block
 * reads
 */
static int cdrom_switch_blocksize(struct cdrom_device_info *cdi, int size)
{
	struct cdrom_device_ops *cdo = cdi->ops;
	struct cdrom_generic_command cgc;
	struct modesel_head mh;

	memset(&mh, 0, sizeof(mh));
	mh.block_desc_length = 0x08;
	mh.block_length_med = (size >> 8) & 0xff;
	mh.block_length_lo = size & 0xff;

	memset(&cgc, 0, sizeof(cgc));
	cgc.cmd[0] = 0x15;
	cgc.cmd[1] = 1 << 4;
	cgc.cmd[4] = 12;
	cgc.buflen = sizeof(mh);
	cgc.buffer = (char *) &mh;
	cgc.data_direction = CGC_DATA_WRITE;
	mh.block_desc_length = 0x08;
	mh.block_length_med = (size >> 8) & 0xff;
	mh.block_length_lo = size & 0xff;

	return cdo->generic_packet(cdi, &cgc);
}

static int cdrom_do_cmd(struct cdrom_device_info *cdi,
			struct cdrom_generic_command *cgc)
{
	struct request_sense *usense, sense;
	unsigned char *ubuf;
	int ret;

	if (cgc->data_direction == CGC_DATA_UNKNOWN)
		return -EINVAL;

	if (cgc->buflen < 0 || cgc->buflen >= 131072)
		return -EINVAL;

	if ((ubuf = cgc->buffer)) {
		cgc->buffer = kmalloc(cgc->buflen, GFP_KERNEL);
		if (cgc->buffer == NULL)
			return -ENOMEM;
	}

	usense = cgc->sense;
	cgc->sense = &sense;
	if (usense && !access_ok(VERIFY_WRITE, usense, sizeof(*usense)))
		return -EFAULT;

	if (cgc->data_direction == CGC_DATA_READ) {
		if (!access_ok(VERIFY_READ, ubuf, cgc->buflen))
			return -EFAULT;
	} else if (cgc->data_direction == CGC_DATA_WRITE) {
		if (copy_from_user(cgc->buffer, ubuf, cgc->buflen)) {
			kfree(cgc->buffer);
			return -EFAULT;
		}
	}

	ret = cdi->ops->generic_packet(cdi, cgc);
	__copy_to_user(usense, cgc->sense, sizeof(*usense));
	if (!ret && cgc->data_direction == CGC_DATA_READ)
		__copy_to_user(ubuf, cgc->buffer, cgc->buflen);
	kfree(cgc->buffer);
	return ret;
}

static int mmc_ioctl(struct cdrom_device_info *cdi, unsigned int cmd,
		     unsigned long arg)
{		
	struct cdrom_device_ops *cdo = cdi->ops;
	struct cdrom_generic_command cgc;
	kdev_t dev = cdi->dev;
	char buffer[32];
	int ret = 0;

	memset(&cgc, 0, sizeof(cgc));

	/* build a unified command and queue it through
	   cdo->generic_packet() */
	switch (cmd) {
	case CDROMREADRAW:
	case CDROMREADMODE1:
	case CDROMREADMODE2: {
		struct cdrom_msf msf;
		int blocksize = 0, format = 0, lba;
		
		switch (cmd) {
		case CDROMREADRAW:
			blocksize = CD_FRAMESIZE_RAW;
			break;
		case CDROMREADMODE1:
			blocksize = CD_FRAMESIZE;
			format = 2;
			break;
		case CDROMREADMODE2:
			blocksize = CD_FRAMESIZE_RAW0;
			break;
		}
		IOCTL_IN(arg, struct cdrom_msf, msf);
		lba = msf_to_lba(msf.cdmsf_min0,msf.cdmsf_sec0,msf.cdmsf_frame0);
		/* FIXME: we need upper bound checking, too!! */
		if (lba < 0)
			return -EINVAL;
		cgc.buffer = (char *) kmalloc(blocksize, GFP_KERNEL);
		if (cgc.buffer == NULL)
			return -ENOMEM;
		cgc.data_direction = CGC_DATA_READ;
		ret = cdrom_read_block(cdi, &cgc, lba, 1, format, blocksize);
		if (ret) {
			/*
			 * SCSI-II devices are not required to support
			 * READ_CD, so let's try switching block size
			 */
			/* FIXME: switch back again... */
			if ((ret = cdrom_switch_blocksize(cdi, blocksize))) {
				kfree(cgc.buffer);
				return ret;
			}
			cgc.sense = NULL;
			ret = cdrom_read_cd(cdi, &cgc, lba, blocksize, 1);
			ret |= cdrom_switch_blocksize(cdi, blocksize);
		}
		if (!ret && copy_to_user((char *)arg, cgc.buffer, blocksize))
			ret = -EFAULT;
		kfree(cgc.buffer);
		return ret;
		}
	case CDROMREADAUDIO: {
		struct cdrom_read_audio ra;
		int lba;

		IOCTL_IN(arg, struct cdrom_read_audio, ra);

		if (ra.addr_format == CDROM_MSF)
			lba = msf_to_lba(ra.addr.msf.minute,
					 ra.addr.msf.second,
					 ra.addr.msf.frame);
		else if (ra.addr_format == CDROM_LBA)
			lba = ra.addr.lba;
		else
			return -EINVAL;

		/* FIXME: we need upper bound checking, too!! */
		if (lba < 0 || ra.nframes <= 0)
			return -EINVAL;

		if ((cgc.buffer = (char *) kmalloc(CD_FRAMESIZE_RAW, GFP_KERNEL)) == NULL)
			return -ENOMEM;

		if (!access_ok(VERIFY_WRITE, ra.buf, ra.nframes*CD_FRAMESIZE_RAW)) {
			kfree(cgc.buffer);
			return -EFAULT;
		}
		cgc.data_direction = CGC_DATA_READ;
		while (ra.nframes > 0) {
			ret = cdrom_read_block(cdi, &cgc, lba, 1, 1, CD_FRAMESIZE_RAW);
			if (ret) break;
			__copy_to_user(ra.buf, cgc.buffer, CD_FRAMESIZE_RAW);
			ra.buf += CD_FRAMESIZE_RAW;
			ra.nframes--;
			lba++;
		}
		kfree(cgc.buffer);
		return ret;
		}
	case CDROMSUBCHNL: {
		struct cdrom_subchnl q;
		u_char requested, back;
		IOCTL_IN(arg, struct cdrom_subchnl, q);
		requested = q.cdsc_format;
		if (!((requested == CDROM_MSF) ||
		      (requested == CDROM_LBA)))
			return -EINVAL;
		q.cdsc_format = CDROM_MSF;
		if ((ret = cdrom_read_subchannel(cdi, &q, 0)))
			return ret;
		back = q.cdsc_format; /* local copy */
		sanitize_format(&q.cdsc_absaddr, &back, requested);
		sanitize_format(&q.cdsc_reladdr, &q.cdsc_format, requested);
		IOCTL_OUT(arg, struct cdrom_subchnl, q);
		/* cdinfo(CD_DO_IOCTL, "CDROMSUBCHNL successful\n"); */ 
		return 0;
		}
	case CDROMPLAYMSF: {
		struct cdrom_msf msf;
		cdinfo(CD_DO_IOCTL, "entering CDROMPLAYMSF\n");
		IOCTL_IN(arg, struct cdrom_msf, msf);
		cgc.cmd[0] = GPCMD_PLAY_AUDIO_MSF;
		cgc.cmd[3] = msf.cdmsf_min0;
		cgc.cmd[4] = msf.cdmsf_sec0;
		cgc.cmd[5] = msf.cdmsf_frame0;
		cgc.cmd[6] = msf.cdmsf_min1;
		cgc.cmd[7] = msf.cdmsf_sec1;
		cgc.cmd[8] = msf.cdmsf_frame1;
		cgc.data_direction = CGC_DATA_NONE;
		return cdo->generic_packet(cdi, &cgc);
		}
	case CDROMPLAYBLK: {
		struct cdrom_blk blk;
		cdinfo(CD_DO_IOCTL, "entering CDROMPLAYBLK\n");
		IOCTL_IN(arg, struct cdrom_blk, blk);
		cgc.cmd[0] = GPCMD_PLAY_AUDIO_10;
		cgc.cmd[2] = (blk.from >> 24) & 0xff;
		cgc.cmd[3] = (blk.from >> 16) & 0xff;
		cgc.cmd[4] = (blk.from >>  8) & 0xff;
		cgc.cmd[5] = blk.from & 0xff;
		cgc.cmd[7] = (blk.len >> 8) & 0xff;
		cgc.cmd[8] = blk.len & 0xff;
		cgc.data_direction = CGC_DATA_NONE;
		return cdo->generic_packet(cdi, &cgc);
		}
	case CDROMVOLCTRL:
	case CDROMVOLREAD: {
		struct cdrom_volctrl volctrl;
		char mask[32];
		unsigned short offset;
		cdinfo(CD_DO_IOCTL, "entering CDROMVOLUME\n");

		IOCTL_IN(arg, struct cdrom_volctrl, volctrl);

		cgc.buffer = buffer;
		cgc.buflen = 24;
		if ((ret = cdrom_mode_sense(cdi, &cgc, GPMODE_AUDIO_CTL_PAGE, 0)))
		    return ret;
		
		/* some drives have longer pages, adjust and reread. */
		if (buffer[1] > cgc.buflen) {
			cgc.buflen = buffer[1] + 2;
			if ((ret = cdrom_mode_sense(cdi, &cgc, 
					GPMODE_AUDIO_CTL_PAGE, 0))) 
			    return ret;
		}
		
		/* get the offset from the length of the page. length
		   is measure from byte 2 an on, thus the 14. */
		offset = buffer[1] - 14;

		/* now we have the current volume settings. if it was only
		   a CDROMVOLREAD, return these values */
		if (cmd == CDROMVOLREAD) {
			volctrl.channel0 = buffer[offset+9];
			volctrl.channel1 = buffer[offset+11];
			volctrl.channel2 = buffer[offset+13];
			volctrl.channel3 = buffer[offset+15];
			IOCTL_OUT(arg, struct cdrom_volctrl, volctrl);
			return 0;
		}
		
		/* get the volume mask */
		cgc.buffer = mask;
		if ((ret = cdrom_mode_sense(cdi, &cgc, 
				GPMODE_AUDIO_CTL_PAGE, 1)))
			return ret;

		buffer[offset+9] = volctrl.channel0 & mask[offset+9];
		buffer[offset+11] = volctrl.channel1 & mask[offset+11];
		buffer[offset+13] = volctrl.channel2 & mask[offset+13];
		buffer[offset+15] = volctrl.channel3 & mask[offset+15];

		/* set volume */
		cgc.buffer = buffer;
		return cdrom_mode_select(cdi, &cgc);
		}

	case CDROMSTART:
	case CDROMSTOP: {
		cdinfo(CD_DO_IOCTL, "entering CDROMSTART/CDROMSTOP\n"); 
		cgc.cmd[0] = GPCMD_START_STOP_UNIT;
		cgc.cmd[1] = 1;
		cgc.cmd[4] = (cmd == CDROMSTART) ? 1 : 0;
		cgc.data_direction = CGC_DATA_NONE;
		return cdo->generic_packet(cdi, &cgc);
		}

	case CDROMPAUSE:
	case CDROMRESUME: {
		cdinfo(CD_DO_IOCTL, "entering CDROMPAUSE/CDROMRESUME\n"); 
		cgc.cmd[0] = GPCMD_PAUSE_RESUME;
		cgc.cmd[8] = (cmd == CDROMRESUME) ? 1 : 0;
		cgc.data_direction = CGC_DATA_NONE;
		return cdo->generic_packet(cdi, &cgc);
		}

	case DVD_READ_STRUCT: {
		dvd_struct *s;
		int size = sizeof(dvd_struct);
		if (!CDROM_CAN(CDC_DVD))
			return -ENOSYS;
		if ((s = (dvd_struct *) kmalloc(size, GFP_KERNEL)) == NULL)
			return -ENOMEM;
		cdinfo(CD_DO_IOCTL, "entering DVD_READ_STRUCT\n"); 
		if (copy_from_user(s, (dvd_struct *)arg, size)) {
			kfree(s);
			return -EFAULT;
		}
		if ((ret = dvd_read_struct(cdi, s))) {
			kfree(s);
			return ret;
		}
		if (copy_to_user((dvd_struct *)arg, s, size))
			ret =