md: use set_capacity_and_notify

Use set_capacity_and_notify to set the size of both the disk and block
device.  This also gets the uevent notifications for the resize for free.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/drivers/md/md-linear.c b/drivers/md/md-linear.c
index 5ab2206..98f1b4b 100644
--- a/drivers/md/md-linear.c
+++ b/drivers/md/md-linear.c
@@ -200,9 +200,8 @@ static int linear_add(struct mddev *mddev, struct md_rdev *rdev)
 		"copied raid_disks doesn't match mddev->raid_disks");
 	rcu_assign_pointer(mddev->private, newconf);
 	md_set_array_sectors(mddev, linear_size(mddev, 0, 0));
-	set_capacity(mddev->gendisk, mddev->array_sectors);
+	set_capacity_and_notify(mddev->gendisk, mddev->array_sectors);
 	mddev_resume(mddev);
-	revalidate_disk_size(mddev->gendisk, true);
 	kfree_rcu(oldconf, rcu);
 	return 0;
 }