swim: use bdev_check_media_change

Switch to use bdev_check_media_change instead of check_disk_change and
call floppy_revalidate manually.  Given that floppy_revalidate only
deals with media change events, the extra call into ->revalidate_disk
from bdev_disk_changed is not required either, so stop wiring up the
method.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drivers/block/swim.c

@@ -217,6 +217,8 @@ extern int swim_read_sector_header(struct swim __iomem *base,
 extern int swim_read_sector_data(struct swim __iomem *base,
 				 unsigned char *data);
 
+static int floppy_revalidate(struct gendisk *disk);
+
 static DEFINE_MUTEX(swim_mutex);
 static inline void set_swim_mode(struct swim __iomem *base, int enable)
 {
@@ -638,7 +640,8 @@ static int floppy_open(struct block_device *bdev, fmode_t mode)
 		return 0;
 
 	if (mode & (FMODE_READ|FMODE_WRITE)) {
-		check_disk_change(bdev);
+		if (bdev_check_media_change(bdev))
+			floppy_revalidate(bdev->bd_disk);
 		if ((mode & FMODE_WRITE) && fs->write_protected) {
 			err = -EROFS;
 			goto out;
@@ -760,7 +763,6 @@ static const struct block_device_operations floppy_fops = {
 	.ioctl		 = floppy_ioctl,
 	.getgeo		 = floppy_getgeo,
 	.check_events	 = floppy_check_events,
-	.revalidate_disk = floppy_revalidate,
 };
 
 static struct kobject *floppy_find(dev_t dev, int *part, void *data)