[PATCH] cdrom helpers

	cdrom_open(), cdrom_release(), cdrom_ioctl() and cdrom_media_changed()
got an additional argument - struct cdrom_device_info *.  Drivers that used
to have them as methods are using wrappers that pass right cdrom_device_info.
Existing callers (in ide-cd.c) updated.  pcd.c, mcdx.c, sbpcd.c and sr.c
got ->private_data in their disks pointing to relevant objects.  Since all
callers of cdrom_find_device() are gone, it got removed.  Since all users
of cdrom_device_info->dev are gone, it's not set anymore (and got removed).

drivers/block/paride/pcd.c

@@ -249,12 +249,37 @@ static int pcd_warned;		/* Have we logged a phase warning ? */
 
 /* kernel glue structures */
 
+static int pcd_block_open(struct inode *inode, struct file *file)
+{
+	struct pcd_unit *cd = inode->i_bdev->bd_disk->private_data;
+	return cdrom_open(&cd->info, inode, file);
+}
+
+static int pcd_block_release(struct inode *inode, struct file *file)
+{
+	struct pcd_unit *cd = inode->i_bdev->bd_disk->private_data;
+	return cdrom_release(&cd->info, file);
+}
+
+static int pcd_block_ioctl(struct inode *inode, struct file *file,
+				unsigned cmd, unsigned long arg)
+{
+	struct pcd_unit *cd = inode->i_bdev->bd_disk->private_data;
+	return cdrom_ioctl(&cd->info, inode, cmd, arg);
+}
+
+static int pcd_block_media_changed(struct gendisk *disk)
+{
+	struct pcd_unit *cd = disk->private_data;
+	return cdrom_media_changed(&cd->info);
+}
+
 static struct block_device_operations pcd_bdops = {
-	.owner			= THIS_MODULE,
-	.open			= cdrom_open,
-	.release		= cdrom_release,
-	.ioctl			= cdrom_ioctl,
-	.check_media_change	= cdrom_media_changed,
+	.owner		= THIS_MODULE,
+	.open		= pcd_block_open,
+	.release	= pcd_block_release,
+	.ioctl		= pcd_block_ioctl,
+	.media_changed	= pcd_block_media_changed,
 };
 
 static struct cdrom_device_ops pcd_dops = {
@@ -297,7 +322,6 @@ static void pcd_init_units(void)
 		snprintf(cd->name, sizeof(cd->info.name), "%s%d", name, unit);
 		cd->info.ops = &pcd_dops;
 		cd->info.handle = cd;
-		cd->info.dev = mk_kdev(major, unit);
 		cd->info.speed = 0;
 		cd->info.capacity = 1;
 		cd->info.mask = 0;
@@ -937,6 +961,7 @@ static int __init pcd_init(void)
 	for (unit = 0, cd = pcd; unit < PCD_UNITS; unit++, cd++) {
 		if (cd->present) {
 			register_cdrom(&cd->info);
+			cd->disk->private_data = cd;
 			add_disk(cd->disk);
 		}
 	}

drivers/cdrom/cdrom.c

@@ -338,14 +338,11 @@ static struct cdrom_device_info *topCdromPtr;
 int register_cdrom(struct cdrom_device_info *cdi)
 {
 	static char banner_printed;
-	int major = major(cdi->dev);
         struct cdrom_device_ops *cdo = cdi->ops;
         int *change_capability = (int *)&cdo->capability; /* hack */
 
 	cdinfo(CD_OPEN, "entering register_cdrom\n"); 
 
-	if (major < 0 || major >= MAX_BLKDEV)
-		return -1;
 	if (cdo->open == NULL || cdo->release == NULL)
 		return -2;
 	if ( !banner_printed ) {
@@ -389,16 +386,11 @@ int register_cdrom(struct cdrom_device_info *cdi)
 int unregister_cdrom(struct cdrom_device_info *unreg)
 {
 	struct cdrom_device_info *cdi, *prev;
-	int major = major(unreg->dev);
-
 	cdinfo(CD_OPEN, "entering unregister_cdrom\n"); 
 
-	if (major < 0 || major >= MAX_BLKDEV)
-		return -1;
-
 	prev = NULL;
 	cdi = topCdromPtr;
-	while (cdi != NULL && !kdev_same(cdi->dev, unreg->dev)) {
+	while (cdi && cdi != unreg) {
 		prev = cdi;
 		cdi = cdi->next;
 	}
@@ -414,17 +406,6 @@ int unregister_cdrom(struct cdrom_device_info *unreg)
 	return 0;
 }
 
-static struct cdrom_device_info *cdrom_find_device(kdev_t dev)
-{
-	struct cdrom_device_info *cdi;
-
-	cdi = topCdromPtr;
-	while (cdi != NULL && !kdev_same(cdi->dev, dev))
-		cdi = cdi->next;
-
-	return cdi;
-}
-
 /* We use the open-option O_NONBLOCK to indicate that the
  * purpose of opening is only for subsequent ioctl() calls; no device
  * integrity checks are performed.
@@ -433,16 +414,11 @@ static struct cdrom_device_info *cdrom_find_device(kdev_t dev)
  * is in their own interest: device control becomes a lot easier
  * this way.
  */
-int cdrom_open(struct inode *ip, struct file *fp)
+int cdrom_open(struct cdrom_device_info *cdi, struct inode *ip, struct file *fp)
 {
-	struct cdrom_device_info *cdi;
-	kdev_t dev = ip->i_rdev;
 	int ret;
 
 	cdinfo(CD_OPEN, "entering cdrom_open\n"); 
-	if ((cdi = cdrom_find_device(dev)) == NULL)
-		return -ENODEV;
-
 	/* if this was a O_NONBLOCK open and we should honor the flags,
 	 * do a quick open without drive/disc integrity checks. */
 	if ((fp->f_flags & O_NONBLOCK) && (cdi->options & CDO_USE_FFLAGS))
@@ -627,10 +603,8 @@ int check_for_audio_disc(struct cdrom_device_info * cdi,
 
 
 /* Admittedly, the logic below could be performed in a nicer way. */
-int cdrom_release(struct inode *ip, struct file *fp)
+int cdrom_release(struct cdrom_device_info *cdi, struct file *fp)
 {
-	kdev_t dev = ip->i_rdev;
-	struct cdrom_device_info *cdi = cdrom_find_device(dev);
 	struct cdrom_device_ops *cdo = cdi->ops;
 	int opened_for_data;
 
@@ -843,9 +817,8 @@ int media_changed(struct cdrom_device_info *cdi, int queue)
 	return ret;
 }
 
-int cdrom_media_changed(kdev_t dev)
+int cdrom_media_changed(struct cdrom_device_info *cdi)
 {
-	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. */ 
@@ -1457,11 +1430,9 @@ static int cdrom_read_block(struct cdrom_device_info *cdi,
  * these days. ATAPI / SCSI specific code now mainly resides in
  * mmc_ioct().
  */
-int cdrom_ioctl(struct inode *ip, struct file *fp, unsigned int cmd,
-		       unsigned long arg)
+int cdrom_ioctl(struct cdrom_device_info *cdi, struct inode *ip,
+		unsigned int cmd, unsigned long arg)
 {
-	kdev_t dev = ip->i_rdev;
-	struct cdrom_device_info *cdi = cdrom_find_device(dev);
 	struct cdrom_device_ops *cdo = cdi->ops;
 	int ret;
 
@@ -1614,7 +1585,7 @@ int cdrom_ioctl(struct inode *ip, struct file *fp, unsigned int cmd,
 		cdinfo(CD_DO_IOCTL, "entering CDROM_RESET\n");
 		if (!CDROM_CAN(CDC_RESET))
 			return -ENOSYS;
-		invalidate_buffers(dev);
+		invalidate_bdev(ip->i_bdev, 0);
 		return cdo->reset(cdi);
 		}
 

drivers/cdrom/cdu31a.c

@@ -3151,15 +3151,6 @@ static void scd_release(struct cdrom_device_info *cdi)
 	sony_usage--;
 }
 
-struct block_device_operations scd_bdops =
-{
-	.owner			= THIS_MODULE,
-	.open			= cdrom_open,
-	.release		= cdrom_release,
-	.ioctl			= cdrom_ioctl,
-	.check_media_change	= cdrom_media_changed,
-};
-
 static struct cdrom_device_ops scd_dops = {
 	.open			= scd_open,
 	.release		= scd_release,
@@ -3188,6 +3179,36 @@ static struct cdrom_device_info scd_info = {
 	.name		= "cdu31a"
 };
 
+static int scd_block_open(struct inode *inode, struct file *file)
+{
+	return cdrom_open(&scd_info, inode, file);
+}
+
+static int scd_block_release(struct inode *inode, struct file *file)
+{
+	return cdrom_release(&scd_info, file);
+}
+
+static int scd_block_ioctl(struct inode *inode, struct file *file,
+				unsigned cmd, unsigned long arg)
+{
+	return cdrom_ioctl(&scd_info, inode, cmd, arg);
+}
+
+static int scd_block_media_changed(struct gendisk *disk)
+{
+	return cdrom_media_changed(&scd_info);
+}
+
+struct block_device_operations scd_bdops =
+{
+	.owner		= THIS_MODULE,
+	.open		= scd_block_open,
+	.release	= scd_block_release,
+	.ioctl		= scd_block_ioctl,
+	.media_changed	= scd_block_media_changed,
+};
+
 static struct gendisk *scd_gendisk;
 
 /* The different types of disc loading mechanisms supported */
@@ -3437,7 +3458,6 @@ int __init cdu31a_init(void)
 	init_timer(&cdu31a_abort_timer);
 	cdu31a_abort_timer.function = handle_abort_timeout;
 
-	scd_info.dev = mk_kdev(MAJOR_NR, 0);
 	scd_info.mask = deficiency;
 	scd_gendisk = disk;
 	if (register_cdrom(&scd_info))

drivers/cdrom/cm206.c

@@ -770,15 +770,6 @@ void get_disc_status(void)
 	}
 }
 
-struct block_device_operations cm206_bdops =
-{
-	.owner			= THIS_MODULE,
-	.open			= cdrom_open,
-	.release		= cdrom_release,
-	.ioctl			= cdrom_ioctl,
-	.check_media_change	= cdrom_media_changed,
-};
-
 /* The new open. The real opening strategy is defined in cdrom.c. */
 
 static int cm206_open(struct cdrom_device_info *cdi, int purpose)
@@ -1357,6 +1348,36 @@ static struct cdrom_device_info cm206_info = {
 	.name		= "cm206",
 };
 
+static int cm206_block_open(struct inode *inode, struct file *file)
+{
+	return cdrom_open(&cm206_info, inode, file);
+}
+
+static int cm206_block_release(struct inode *inode, struct file *file)
+{
+	return cdrom_release(&cm206_info, file);
+}
+
+static int cm206_block_ioctl(struct inode *inode, struct file *file,
+				unsigned cmd, unsigned long arg)
+{
+	return cdrom_ioctl(&cm206_info, inode, cmd, arg);
+}
+
+static int cm206_block_media_changed(struct gendisk *disk)
+{
+	return cdrom_media_changed(&cm206_info);
+}
+
+static struct block_device_operations cm206_bdops =
+{
+	.owner		= THIS_MODULE,
+	.open		= cm206_block_open,
+	.release	= cm206_block_release,
+	.ioctl		= cm206_block_ioctl,
+	.media_changed	= cm206_block_media_changed,
+};
+
 static struct gendisk *cm206_gendisk;
 
 /* This function probes for the adapter card. It returns the base
@@ -1479,7 +1500,6 @@ int __init cm206_init(void)
 	disk->fops = &cm206_bdops;
 	disk->flags = GENHD_FL_CD;
 	cm206_gendisk = disk;
-	cm206_info.dev = mk_kdev(MAJOR_NR, 0);
 	if (register_cdrom(&cm206_info) != 0) {
 		printk(KERN_INFO "Cannot register for cdrom %d!\n", MAJOR_NR);
 		goto out_cdrom;

drivers/cdrom/mcd.c

@@ -192,15 +192,6 @@ int mcd_audio_ioctl(struct cdrom_device_info *cdi, unsigned int cmd,
 		    void *arg);
 int mcd_drive_status(struct cdrom_device_info *cdi, int slot_nr);
 
-struct block_device_operations mcd_bdops =
-{
-	.owner			= THIS_MODULE,
-	.open			= cdrom_open,
-	.release		= cdrom_release,
-	.ioctl			= cdrom_ioctl,
-	.check_media_change	= cdrom_media_changed,
-};
-
 static struct timer_list mcd_timer;
 
 static struct cdrom_device_ops mcd_dops = {
@@ -221,6 +212,36 @@ static struct cdrom_device_info mcd_info = {
 	.name		= "mcd",
 };
 
+static int mcd_block_open(struct inode *inode, struct file *file)
+{
+	return cdrom_open(&mcd_info, inode, file);
+}
+
+static int mcd_block_release(struct inode *inode, struct file *file)
+{
+	return cdrom_release(&mcd_info, file);
+}
+
+static int mcd_block_ioctl(struct inode *inode, struct file *file,
+				unsigned cmd, unsigned long arg)
+{
+	return cdrom_ioctl(&mcd_info, inode, cmd, arg);
+}
+
+static int mcd_block_media_changed(struct gendisk *disk)
+{
+	return cdrom_media_changed(&mcd_info);
+}
+
+static struct block_device_operations mcd_bdops =
+{
+	.owner		= THIS_MODULE,
+	.open		= mcd_block_open,
+	.release	= mcd_block_release,
+	.ioctl		= mcd_block_ioctl,
+	.media_changed	= mcd_block_media_changed,
+};
+
 static struct gendisk *mcd_gendisk;
 
 #ifndef MODULE
@@ -1128,7 +1149,6 @@ int __init mcd_init(void)
 	disk->fops = &mcd_bdops;
 	disk->flags = GENHD_FL_CD;
 	mcd_gendisk = disk;
-	mcd_info.dev = mk_kdev(MAJOR_NR, 0);
 
 	if (register_cdrom(&mcd_info) != 0) {
 		printk(KERN_ERR "mcd: Unable to register Mitsumi CD-ROM.\n");

drivers/cdrom/mcdx.c

@@ -220,13 +220,38 @@ struct s_drive_stuff {
 int mcdx_init(void);
 void do_mcdx_request(request_queue_t * q);
 
-struct block_device_operations mcdx_bdops =
+static int mcdx_block_open(struct inode *inode, struct file *file)
 {
-	owner:			THIS_MODULE,
-	open:			cdrom_open,
-	release:		cdrom_release,
-	ioctl:			cdrom_ioctl,
-	check_media_change:	cdrom_media_changed,
+	struct s_drive_stuff *p = inode->i_bdev->bd_disk->private_data;
+	return cdrom_open(&p->info, inode, file);
+}
+
+static int mcdx_block_release(struct inode *inode, struct file *file)
+{
+	struct s_drive_stuff *p = inode->i_bdev->bd_disk->private_data;
+	return cdrom_release(&p->info, file);
+}
+
+static int mcdx_block_ioctl(struct inode *inode, struct file *file,
+				unsigned cmd, unsigned long arg)
+{
+	struct s_drive_stuff *p = inode->i_bdev->bd_disk->private_data;
+	return cdrom_ioctl(&p->info, inode, cmd, arg);
+}
+
+static int mcdx_block_media_changed(struct gendisk *disk)
+{
+	struct s_drive_stuff *p = disk->private_data;
+	return cdrom_media_changed(&p->info);
+}
+
+static struct block_device_operations mcdx_bdops =
+{
+	.owner		= THIS_MODULE,
+	.open		= mcdx_block_open,
+	.release	= mcdx_block_release,
+	.ioctl		= mcdx_block_ioctl,
+	.media_changed	= mcdx_block_media_changed,
 };
 
 
@@ -1218,7 +1243,6 @@ int __init mcdx_init_drive(int drive)
 	stuffp->info.capacity = 1;
 	stuffp->info.handle = stuffp;
 	sprintf(stuffp->info.name, "mcdx%d", drive);
-	stuffp->info.dev = mk_kdev(MAJOR_NR, drive);
 	disk->major = MAJOR_NR;
 	disk->first_minor = drive;
 	strcpy(disk->disk_name, stuffp->info.name);
@@ -1243,6 +1267,7 @@ int __init mcdx_init_drive(int drive)
 		blk_cleanup_queue(BLK_DEFAULT_QUEUE(MAJOR_NR));
 		return 2;
 	}
+	disk->private_data = stuffp;
 	add_disk(disk);
 	printk(msg);
 	return 0;

drivers/cdrom/sbpcd.c

@@ -5351,13 +5351,38 @@ static int sbp_data(struct request *req)
 }
 /*==========================================================================*/
 
+static int sbpcd_block_open(struct inode *inode, struct file *file)
+{
+	struct sbpcd_drive *p = inode->i_bdev->bd_disk->private_data;
+	return cdrom_open(p->sbpcd_infop, inode, file);
+}
+
+static int sbpcd_block_release(struct inode *inode, struct file *file)
+{
+	struct sbpcd_drive *p = inode->i_bdev->bd_disk->private_data;
+	return cdrom_release(p->sbpcd_infop, file);
+}
+
+static int sbpcd_block_ioctl(struct inode *inode, struct file *file,
+				unsigned cmd, unsigned long arg)
+{
+	struct sbpcd_drive *p = inode->i_bdev->bd_disk->private_data;
+	return cdrom_ioctl(p->sbpcd_infop, inode, cmd, arg);
+}
+
+static int sbpcd_block_media_changed(struct gendisk *disk)
+{
+	struct sbpcd_drive *p = disk->private_data;
+	return cdrom_media_changed(p->sbpcd_infop);
+}
+
 static struct block_device_operations sbpcd_bdops =
 {
-	owner:			THIS_MODULE,
-	open:			cdrom_open,
-	release:		cdrom_release,
-	ioctl:			cdrom_ioctl,
-	check_media_change:	cdrom_media_changed,
+	.owner		= THIS_MODULE,
+	.open		= sbpcd_block_open,
+	.release	= sbpcd_block_release,
+	.ioctl		= sbpcd_block_ioctl,
+	.media_changed	= sbpcd_block_media_changed,
 };
 /*==========================================================================*/
 /*
@@ -5828,7 +5853,6 @@ int __init sbpcd_init(void)
 		sbpcd_infop->speed = 2;
 		sbpcd_infop->capacity = 1;
 		sprintf(sbpcd_infop->name, "sbpcd%d", j);
-		sbpcd_infop->dev = mk_kdev(MAJOR_NR, j);
 		sbpcd_infop->handle = p;
 		p->sbpcd_infop = sbpcd_infop;
 		disk = alloc_disk(1);
@@ -5844,6 +5868,7 @@ int __init sbpcd_init(void)
 		{
 			printk(" sbpcd: Unable to register with Uniform CD-ROm driver\n");
 		}
+		disk->private_data = p;
 		add_disk(disk);
 	}
 	blk_queue_hardsect_size(BLK_DEFAULT_QUEUE(MAJOR_NR), CD_FRAMESIZE);
@@ -5874,7 +5899,6 @@ void sbpcd_exit(void)
 		put_disk(D_S[j].disk);
 		vfree(D_S[j].sbp_buf);
 		if (D_S[j].sbp_audsiz>0) vfree(D_S[j].aud_buf);
-		devfs_unregister(D_S[j].disk.de);
 		if ((unregister_cdrom(D_S[j].sbpcd_infop) == -EINVAL))
 		{
 			msg(DBG_INF, "What's that: can't unregister info %s.\n", major_name);

drivers/cdrom/sonycd535.c

@@ -1585,7 +1585,7 @@ static int __init sony535_init(void)
 	blk_init_queue(BLK_DEFAULT_QUEUE(MAJOR_NR), do_cdu535_request,
 			&sonycd535_lock);
 	blk_queue_hardsect_size(BLK_DEFAULT_QUEUE(MAJOR_NR), CDU535_BLOCK_SIZE);
-	sony_toc = kamlloc(sizeof(struct s535_sony_toc), GFP_KERNEL);
+	sony_toc = kmalloc(sizeof(struct s535_sony_toc), GFP_KERNEL);
 	err = -ENOMEM;
 	if (!sony_toc)
 		goto out2;

drivers/ide/ide-cd.c

@@ -2647,7 +2647,6 @@ static int ide_cdrom_register (ide_drive_t *drive, int nslots)
 	struct cdrom_info *info = drive->driver_data;
 	struct cdrom_device_info *devinfo = &info->devinfo;
 
-	devinfo->dev = mk_kdev(drive->disk->major, drive->disk->first_minor);
 	devinfo->ops = &ide_cdrom_dops;
 	devinfo->mask = 0;
 	devinfo->speed = CDROM_STATE_FLAGS(drive)->current_speed;
@@ -3026,6 +3025,7 @@ int ide_cdrom_ioctl (ide_drive_t *drive,
 		     struct inode *inode, struct file *file,
 		     unsigned int cmd, unsigned long arg)
 {
+	struct cdrom_info *info = drive->driver_data;
 	int error;
 
 	/* Try the generic SCSI command ioctl's first.. */
@@ -3034,7 +3034,7 @@ int ide_cdrom_ioctl (ide_drive_t *drive,
 		return error;
 
 	/* Then the generic cdrom ioctl's.. */
-	return cdrom_ioctl(inode, file, cmd, arg);
+	return cdrom_ioctl(&info->devinfo, inode, cmd, arg);
 }
 
 static
@@ -3044,9 +3044,9 @@ int ide_cdrom_open (struct inode *ip, struct file *fp, ide_drive_t *drive)
 	int rc = -ENOMEM;
 
 	MOD_INC_USE_COUNT;
-	if (info->buffer == NULL)
+	if (!info->buffer)
 		info->buffer = (char *) kmalloc(SECTOR_BUFFER_SIZE, GFP_KERNEL);
-        if ((info->buffer == NULL) || (rc = cdrom_open(ip, fp))) {
+        if (!info->buffer || (rc = cdrom_open(&info->devinfo, ip, fp))) {
 		drive->usage--;
 		MOD_DEC_USE_COUNT;
 	}
@@ -3057,15 +3057,16 @@ static
 void ide_cdrom_release (struct inode *inode, struct file *file,
 			ide_drive_t *drive)
 {
-	cdrom_release (inode, file);
+	struct cdrom_info *info = drive->driver_data;
+	cdrom_release (&info->devinfo, file);
 	MOD_DEC_USE_COUNT;
 }
 
 static
 int ide_cdrom_check_media_change (ide_drive_t *drive)
 {
-	return cdrom_media_changed(mk_kdev(drive->disk->major,
-			drive->disk->first_minor));
+	struct cdrom_info *info = drive->driver_data;
+	return cdrom_media_changed(&info->devinfo);
 }
 
 static

drivers/scsi/sr.c

@@ -386,13 +386,38 @@ static int sr_init_command(Scsi_Cmnd * SCpnt)
 	return 1;
 }
 
+static int sr_block_open(struct inode *inode, struct file *file)
+{
+	Scsi_CD *cd = inode->i_bdev->bd_disk->private_data;
+	return cdrom_open(&cd->cdi, inode, file);
+}
+
+static int sr_block_release(struct inode *inode, struct file *file)
+{
+	Scsi_CD *cd = inode->i_bdev->bd_disk->private_data;
+	return cdrom_release(&cd->cdi, file);
+}
+
+static int sr_block_ioctl(struct inode *inode, struct file *file, unsigned cmd,
+			  unsigned long arg)
+{
+	Scsi_CD *cd = inode->i_bdev->bd_disk->private_data;
+	return cdrom_ioctl(&cd->cdi, inode, cmd, arg);
+}
+
+static int sr_block_media_changed(struct gendisk *disk)
+{
+	Scsi_CD *cd = disk->private_data;
+	return cdrom_media_changed(&cd->cdi);
+}
+
 struct block_device_operations sr_bdops =
 {
-	owner:			THIS_MODULE,
-	open:			cdrom_open,
-	release:		cdrom_release,
-	ioctl:			cdrom_ioctl,
-	check_media_change:	cdrom_media_changed,
+	.owner		= THIS_MODULE,
+	.open		= sr_block_open,
+	.release	= sr_block_release,
+	.ioctl		= sr_block_ioctl,
+	.media_changed	= sr_block_media_changed,
 };
 
 static int sr_open(struct cdrom_device_info *cdi, int purpose)
@@ -757,7 +782,6 @@ void sr_finish()
 
 		cd->cdi.ops = &sr_dops;
 		cd->cdi.handle = cd;
-		cd->cdi.dev = mk_kdev(MAJOR_NR, i);
 		cd->cdi.mask = 0;
 		cd->cdi.capacity = 1;
 		/*
@@ -770,6 +794,7 @@ void sr_finish()
 		disk->driverfs_dev = &cd->device->sdev_driverfs_dev;
 		register_cdrom(&cd->cdi);
 		set_capacity(disk, cd->capacity);
+		disk->private_data = cd;
 		add_disk(disk);
 	}
 }

include/linux/cdrom.h

@@ -731,7 +731,6 @@ struct cdrom_device_info {
 	struct cdrom_device_info *next; /* next device_info for this major */
 	void *handle;		        /* driver-dependent data */
 /* specifications */
-        kdev_t dev;	                /* device number */
 	int mask;                       /* mask of capability: disables them */
 	int speed;			/* maximum speed for reading data */
 	int capacity;			/* number of discs in jukebox */
@@ -776,10 +775,10 @@ struct cdrom_device_ops {
 };
 
 /* the general block_device operations structure: */
-extern int cdrom_open(struct inode *, struct file *);
-extern int cdrom_release(struct inode *, struct file *);
-extern int cdrom_ioctl(struct inode *, struct file *, unsigned, unsigned long);
-extern int cdrom_media_changed(kdev_t);
+extern int cdrom_open(struct cdrom_device_info *, struct inode *, struct file *);
+extern int cdrom_release(struct cdrom_device_info *, struct file *);
+extern int cdrom_ioctl(struct cdrom_device_info *, struct inode *, unsigned, unsigned long);
+extern int cdrom_media_changed(struct cdrom_device_info *);
 
 extern int register_cdrom(struct cdrom_device_info *cdi);
 extern int unregister_cdrom(struct cdrom_device_info *cdi);