swim[3]: Convert to bdops->check_events()

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

Both swim and swim3 buffer media changed state and clear it on
revalidation.  They will behave correctly with kernel event polling.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Laurent Vivier <laurent@lvivier.info>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/drivers/block/swim.c b/drivers/block/swim.c
index 75333d0..24a482f 100644
--- a/drivers/block/swim.c
+++ b/drivers/block/swim.c
@@ -741,11 +741,12 @@
 	return 0;
 }
 
-static int floppy_check_change(struct gendisk *disk)
+static unsigned int floppy_check_events(struct gendisk *disk,
+					unsigned int clearing)
 {
 	struct floppy_state *fs = disk->private_data;
 
-	return fs->ejected;
+	return fs->ejected ? DISK_EVENT_MEDIA_CHANGE : 0;
 }
 
 static int floppy_revalidate(struct gendisk *disk)
@@ -772,7 +773,7 @@
 	.release	 = floppy_release,
 	.ioctl		 = floppy_ioctl,
 	.getgeo		 = floppy_getgeo,
-	.media_changed	 = floppy_check_change,
+	.check_events	 = floppy_check_events,
 	.revalidate_disk = floppy_revalidate,
 };
 
@@ -857,6 +858,7 @@
 		swd->unit[drive].disk->first_minor = drive;
 		sprintf(swd->unit[drive].disk->disk_name, "fd%d", drive);
 		swd->unit[drive].disk->fops = &floppy_fops;
+		swd->unit[drive].disk->events = DISK_EVENT_MEDIA_CHANGE;
 		swd->unit[drive].disk->private_data = &swd->unit[drive];
 		swd->unit[drive].disk->queue = swd->queue;
 		set_capacity(swd->unit[drive].disk, 2880);