pktcdvd: Convert to bdops->check_events()

Convert from ->media_changed() to ->check_events().

pktcdvd needs to forward all event related operations to the
underlying device.  Forward ->check_events() instead of
->media_changed() and inherit disk->[async_]events.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Peter Osterlund <petero2@telia.com>

drivers/block/pktcdvd.c

@@ -2796,7 +2796,8 @@ static int pkt_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd,
 	return ret;
 }
 
-static int pkt_media_changed(struct gendisk *disk)
+static unsigned int pkt_check_events(struct gendisk *disk,
+				     unsigned int clearing)
 {
 	struct pktcdvd_device *pd = disk->private_data;
 	struct gendisk *attached_disk;
@@ -2806,9 +2807,9 @@ static int pkt_media_changed(struct gendisk *disk)
 	if (!pd->bdev)
 		return 0;
 	attached_disk = pd->bdev->bd_disk;
-	if (!attached_disk)
+	if (!attached_disk || !attached_disk->fops->check_events)
 		return 0;
-	return attached_disk->fops->media_changed(attached_disk);
+	return attached_disk->fops->check_events(attached_disk, clearing);
 }
 
 static const struct block_device_operations pktcdvd_ops = {
@@ -2816,7 +2817,7 @@ static const struct block_device_operations pktcdvd_ops = {
 	.open =			pkt_open,
 	.release =		pkt_close,
 	.ioctl =		pkt_ioctl,
-	.media_changed =	pkt_media_changed,
+	.check_events =		pkt_check_events,
 };
 
 static char *pktcdvd_devnode(struct gendisk *gd, mode_t *mode)
@@ -2889,6 +2890,10 @@ static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev)
 	if (ret)
 		goto out_new_dev;
 
+	/* inherit events of the host device */
+	disk->events = pd->bdev->bd_disk->events;
+	disk->async_events = pd->bdev->bd_disk->async_events;
+
 	add_disk(disk);
 
 	pkt_sysfs_dev_new(pd);