cdrom.c

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int cdrom_get_media_event(struct cdrom_device_info *cdi,
			  struct media_event_desc *med)
{
	struct packet_command cgc;
	unsigned char buffer[8];
	struct event_header *eh = (struct event_header *) buffer;

	init_cdrom_command(&cgc, buffer, sizeof(buffer), CGC_DATA_READ);
	cgc.cmd[0] = GPCMD_GET_EVENT_STATUS_NOTIFICATION;
	cgc.cmd[1] = 1;		/* IMMED */
	cgc.cmd[4] = 1 << 4;	/* media event */
	cgc.cmd[8] = sizeof(buffer);
	cgc.quiet = 1;

	if (cdi->ops->generic_packet(cdi, &cgc))
		return 1;

	if (be16_to_cpu(eh->data_len) < sizeof(*med))
		return 1;

	if (eh->nea || eh->notification_class != 0x4)
		return 1;

	memcpy(med, &buffer[sizeof(*eh)], sizeof(*med));
	return 0;
}

/*
 * the first prototypes used 0x2c as the page code for the mrw mode page,
 * subsequently this was changed to 0x03. probe the one used by this drive
 */
static int cdrom_mrw_probe_pc(struct cdrom_device_info *cdi)
{
	struct packet_command cgc;
	char buffer[16];

	init_cdrom_command(&cgc, buffer, sizeof(buffer), CGC_DATA_READ);

	cgc.timeout = HZ;
	cgc.quiet = 1;

	if (!cdrom_mode_sense(cdi, &cgc, MRW_MODE_PC, 0)) {
		cdi->mrw_mode_page = MRW_MODE_PC;
		return 0;
	} else if (!cdrom_mode_sense(cdi, &cgc, MRW_MODE_PC_PRE1, 0)) {
		cdi->mrw_mode_page = MRW_MODE_PC_PRE1;
		return 0;
	}

	return 1;
}

static int cdrom_is_mrw(struct cdrom_device_info *cdi, int *write)
{
	struct packet_command cgc;
	struct mrw_feature_desc *mfd;
	unsigned char buffer[16];
	int ret;

	*write = 0;

	init_cdrom_command(&cgc, buffer, sizeof(buffer), CGC_DATA_READ);

	cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
	cgc.cmd[3] = CDF_MRW;
	cgc.cmd[8] = sizeof(buffer);
	cgc.quiet = 1;

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

	mfd = (struct mrw_feature_desc *)&buffer[sizeof(struct feature_header)];
	if (be16_to_cpu(mfd->feature_code) != CDF_MRW)
		return 1;
	*write = mfd->write;

	if ((ret = cdrom_mrw_probe_pc(cdi))) {
		*write = 0;
		return ret;
	}

	return 0;
}

static int cdrom_mrw_bgformat(struct cdrom_device_info *cdi, int cont)
{
	struct packet_command cgc;
	unsigned char buffer[12];
	int ret;

	printk(KERN_INFO "cdrom: %sstarting format\n", cont ? "Re" : "");

	/*
	 * FmtData bit set (bit 4), format type is 1
	 */
	init_cdrom_command(&cgc, buffer, sizeof(buffer), CGC_DATA_WRITE);
	cgc.cmd[0] = GPCMD_FORMAT_UNIT;
	cgc.cmd[1] = (1 << 4) | 1;

	cgc.timeout = 5 * 60 * HZ;

	/*
	 * 4 byte format list header, 8 byte format list descriptor
	 */
	buffer[1] = 1 << 1;
	buffer[3] = 8;

	/*
	 * nr_blocks field
	 */
	buffer[4] = 0xff;
	buffer[5] = 0xff;
	buffer[6] = 0xff;
	buffer[7] = 0xff;

	buffer[8] = 0x24 << 2;
	buffer[11] = cont;

	ret = cdi->ops->generic_packet(cdi, &cgc);
	if (ret)
		printk(KERN_INFO "cdrom: bgformat failed\n");

	return ret;
}

static int cdrom_mrw_bgformat_susp(struct cdrom_device_info *cdi, int immed)
{
	struct packet_command cgc;

	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
	cgc.cmd[0] = GPCMD_CLOSE_TRACK;

	/*
	 * Session = 1, Track = 0
	 */
	cgc.cmd[1] = !!immed;
	cgc.cmd[2] = 1 << 1;

	cgc.timeout = 5 * 60 * HZ;

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

static int cdrom_flush_cache(struct cdrom_device_info *cdi)
{
	struct packet_command cgc;

	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
	cgc.cmd[0] = GPCMD_FLUSH_CACHE;

	cgc.timeout = 5 * 60 * HZ;

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

static int cdrom_mrw_exit(struct cdrom_device_info *cdi)
{
	disc_information di;
	int ret;

	ret = cdrom_get_disc_info(cdi, &di);
	if (ret < 0 || ret < (int)offsetof(typeof(di),disc_type))
		return 1;

	ret = 0;
	if (di.mrw_status == CDM_MRW_BGFORMAT_ACTIVE) {
		printk(KERN_INFO "cdrom: issuing MRW back ground "
				"format suspend\n");
		ret = cdrom_mrw_bgformat_susp(cdi, 0);
	}

	if (!ret && cdi->media_written)
		ret = cdrom_flush_cache(cdi);

	return ret;
}

static int cdrom_mrw_set_lba_space(struct cdrom_device_info *cdi, int space)
{
	struct packet_command cgc;
	struct mode_page_header *mph;
	char buffer[16];
	int ret, offset, size;

	init_cdrom_command(&cgc, buffer, sizeof(buffer), CGC_DATA_READ);

	cgc.buffer = buffer;
	cgc.buflen = sizeof(buffer);

	if ((ret = cdrom_mode_sense(cdi, &cgc, cdi->mrw_mode_page, 0)))
		return ret;

	mph = (struct mode_page_header *) buffer;
	offset = be16_to_cpu(mph->desc_length);
	size = be16_to_cpu(mph->mode_data_length) + 2;

	buffer[offset + 3] = space;
	cgc.buflen = size;

	if ((ret = cdrom_mode_select(cdi, &cgc)))
		return ret;

	printk(KERN_INFO "cdrom: %s: mrw address space %s selected\n", cdi->name, mrw_address_space[space]);
	return 0;
}

static int cdrom_get_random_writable(struct cdrom_device_info *cdi,
			      struct rwrt_feature_desc *rfd)
{
	struct packet_command cgc;
	char buffer[24];
	int ret;

	init_cdrom_command(&cgc, buffer, sizeof(buffer), CGC_DATA_READ);

	cgc.cmd[0] = GPCMD_GET_CONFIGURATION;	/* often 0x46 */
	cgc.cmd[3] = CDF_RWRT;			/* often 0x0020 */
	cgc.cmd[8] = sizeof(buffer);		/* often 0x18 */
	cgc.quiet = 1;

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

	memcpy(rfd, &buffer[sizeof(struct feature_header)], sizeof (*rfd));
	return 0;
}

static int cdrom_has_defect_mgt(struct cdrom_device_info *cdi)
{
	struct packet_command cgc;
	char buffer[16];
	__be16 *feature_code;
	int ret;

	init_cdrom_command(&cgc, buffer, sizeof(buffer), CGC_DATA_READ);

	cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
	cgc.cmd[3] = CDF_HWDM;
	cgc.cmd[8] = sizeof(buffer);
	cgc.quiet = 1;

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

	feature_code = (__be16 *) &buffer[sizeof(struct feature_header)];
	if (be16_to_cpu(*feature_code) == CDF_HWDM)
		return 0;

	return 1;
}


static int cdrom_is_random_writable(struct cdrom_device_info *cdi, int *write)
{
	struct rwrt_feature_desc rfd;
	int ret;

	*write = 0;

	if ((ret = cdrom_get_random_writable(cdi, &rfd)))
		return ret;

	if (CDF_RWRT == be16_to_cpu(rfd.feature_code))
		*write = 1;

	return 0;
}

static int cdrom_media_erasable(struct cdrom_device_info *cdi)
{
	disc_information di;
	int ret;

	ret = cdrom_get_disc_info(cdi, &di);
	if (ret < 0 || ret < offsetof(typeof(di), n_first_track))
		return -1;

	return di.erasable;
}

/*
 * FIXME: check RO bit
 */
static int cdrom_dvdram_open_write(struct cdrom_device_info *cdi)
{
	int ret = cdrom_media_erasable(cdi);

	/*
	 * allow writable open if media info read worked and media is
	 * erasable, _or_ if it fails since not all drives support it
	 */
	if (!ret)
		return 1;

	return 0;
}

static int cdrom_mrw_open_write(struct cdrom_device_info *cdi)
{
	disc_information di;
	int ret;

	/*
	 * always reset to DMA lba space on open
	 */
	if (cdrom_mrw_set_lba_space(cdi, MRW_LBA_DMA)) {
		printk(KERN_ERR "cdrom: failed setting lba address space\n");
		return 1;
	}

	ret = cdrom_get_disc_info(cdi, &di);
	if (ret < 0 || ret < offsetof(typeof(di),disc_type))
		return 1;

	if (!di.erasable)
		return 1;

	/*
	 * mrw_status
	 * 0	-	not MRW formatted
	 * 1	-	MRW bgformat started, but not running or complete
	 * 2	-	MRW bgformat in progress
	 * 3	-	MRW formatting complete
	 */
	ret = 0;
	printk(KERN_INFO "cdrom open: mrw_status '%s'\n",
			mrw_format_status[di.mrw_status]);
	if (!di.mrw_status)
		ret = 1;
	else if (di.mrw_status == CDM_MRW_BGFORMAT_INACTIVE &&
			mrw_format_restart)
		ret = cdrom_mrw_bgformat(cdi, 1);

	return ret;
}

static int mo_open_write(struct cdrom_device_info *cdi)
{
	struct packet_command cgc;
	char buffer[255];
	int ret;

	init_cdrom_command(&cgc, &buffer, 4, CGC_DATA_READ);
	cgc.quiet = 1;

	/*
	 * obtain write protect information as per
	 * drivers/scsi/sd.c:sd_read_write_protect_flag
	 */

	ret = cdrom_mode_sense(cdi, &cgc, GPMODE_ALL_PAGES, 0);
	if (ret)
		ret = cdrom_mode_sense(cdi, &cgc, GPMODE_VENDOR_PAGE, 0);
	if (ret) {
		cgc.buflen = 255;
		ret = cdrom_mode_sense(cdi, &cgc, GPMODE_ALL_PAGES, 0);
	}

	/* drive gave us no info, let the user go ahead */
	if (ret)
		return 0;

	return buffer[3] & 0x80;
}

static int cdrom_ram_open_write(struct cdrom_device_info *cdi)
{
	struct rwrt_feature_desc rfd;
	int ret;

	if ((ret = cdrom_has_defect_mgt(cdi)))
		return ret;

	if ((ret = cdrom_get_random_writable(cdi, &rfd)))
		return ret;
	else if (CDF_RWRT == be16_to_cpu(rfd.feature_code))
		ret = !rfd.curr;

	cdinfo(CD_OPEN, "can open for random write\n");
	return ret;
}

static void cdrom_mmc3_profile(struct cdrom_device_info *cdi)
{
	struct packet_command cgc;
	char buffer[32];
	int ret, mmc3_profile;

	init_cdrom_command(&cgc, buffer, sizeof(buffer), CGC_DATA_READ);

	cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
	cgc.cmd[1] = 0;
	cgc.cmd[2] = cgc.cmd[3] = 0;		/* Starting Feature Number */
	cgc.cmd[8] = sizeof(buffer);		/* Allocation Length */
	cgc.quiet = 1;

	if ((ret = cdi->ops->generic_packet(cdi, &cgc)))
		mmc3_profile = 0xffff;
	else
		mmc3_profile = (buffer[6] << 8) | buffer[7];

	cdi->mmc3_profile = mmc3_profile;
}

static int cdrom_is_dvd_rw(struct cdrom_device_info *cdi)
{
	switch (cdi->mmc3_profile) {
	case 0x12:	/* DVD-RAM	*/
	case 0x1A:	/* DVD+RW	*/
		return 0;
	default:
		return 1;
	}
}

/*
 * returns 0 for ok to open write, non-0 to disallow
 */
static int cdrom_open_write(struct cdrom_device_info *cdi)
{
	int mrw, mrw_write, ram_write;
	int ret = 1;

	mrw = 0;
	if (!cdrom_is_mrw(cdi, &mrw_write))
		mrw = 1;

	if (CDROM_CAN(CDC_MO_DRIVE))
		ram_write = 1;
	else
		(void) cdrom_is_random_writable(cdi, &ram_write);
	
	if (mrw)
		cdi->mask &= ~CDC_MRW;
	else
		cdi->mask |= CDC_MRW;

	if (mrw_write)
		cdi->mask &= ~CDC_MRW_W;
	else
		cdi->mask |= CDC_MRW_W;

	if (ram_write)
		cdi->mask &= ~CDC_RAM;
	else
		cdi->mask |= CDC_RAM;

	if (CDROM_CAN(CDC_MRW_W))
		ret = cdrom_mrw_open_write(cdi);
	else if (CDROM_CAN(CDC_DVD_RAM))
		ret = cdrom_dvdram_open_write(cdi);
 	else if (CDROM_CAN(CDC_RAM) &&
 		 !CDROM_CAN(CDC_CD_R|CDC_CD_RW|CDC_DVD|CDC_DVD_R|CDC_MRW|CDC_MO_DRIVE))
 		ret = cdrom_ram_open_write(cdi);
	else if (CDROM_CAN(CDC_MO_DRIVE))
		ret = mo_open_write(cdi);
	else if (!cdrom_is_dvd_rw(cdi))
		ret = 0;

	return ret;
}

static void cdrom_dvd_rw_close_write(struct cdrom_device_info *cdi)
{
	struct packet_command cgc;

	if (cdi->mmc3_profile != 0x1a) {
		cdinfo(CD_CLOSE, "%s: No DVD+RW\n", cdi->name);
		return;
	}

	if (!cdi->media_written) {
		cdinfo(CD_CLOSE, "%s: DVD+RW media clean\n", cdi->name);
		return;
	}

	printk(KERN_INFO "cdrom: %s: dirty DVD+RW media, \"finalizing\"\n",
	       cdi->name);

	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);