block: move more syncing and invalidation to delete_partition

Move the calls to fsync_bdev and __invalidate_device from del_gendisk to
delete_partition.  For the other two callers that check that there are
no openers for the delete partitions(s) the callouts are a no-op as no
file system can be mounted, but this keeps all the cleanup in one
place.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210406062303.811835-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/genhd.c

@@ -686,11 +686,8 @@ void del_gendisk(struct gendisk *disk)
 
 	/* invalidate stuff */
 	disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
-	while ((part = disk_part_iter_next(&piter))) {
-		fsync_bdev(part);
-		__invalidate_device(part, true);
+	while ((part = disk_part_iter_next(&piter)))
 		delete_partition(part);
-	}
 	disk_part_iter_exit(&piter);
 
 	fsync_bdev(disk->part0);

block/partitions/core.c

@@ -287,6 +287,9 @@ struct device_type part_type = {
  */
 void delete_partition(struct block_device *part)
 {
+	fsync_bdev(part);
+	__invalidate_device(part, true);
+
 	xa_erase(&part->bd_disk->part_tbl, part->bd_partno);
 	kobject_put(part->bd_holder_dir);
 	device_del(&part->bd_device);
@@ -468,9 +471,6 @@ int bdev_del_partition(struct block_device *bdev, int partno)
 	if (part->bd_openers)
 		goto out_unlock;
 
-	sync_blockdev(part);
-	invalidate_bdev(part);
-
 	delete_partition(part);
 	ret = 0;
 out_unlock: