Btrfs: run orphan cleanup on default fs root

This patch revert's commit

6c090a11e1c403b727a6a8eff0b97d5fb9e95cb5

Since it introduces this problem where we can run orphan cleanup on a
volume that can have orphan entries re-added.  Instead of my original
fix, Yan Zheng pointed out that we can just revert my original fix and
then run the orphan cleanup in open_ctree after we look up the fs_root.
I have tested this with all the tests that gave me problems and this
patch fixes both problems.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

fs/btrfs/disk-io.c

@@ -1993,6 +1993,12 @@ struct btrfs_root *open_ctree(struct super_block *sb,
 	if (!fs_info->fs_root)
 		goto fail_trans_kthread;
 
+	if (!(sb->s_flags & MS_RDONLY)) {
+		down_read(&fs_info->cleanup_work_sem);
+		btrfs_orphan_cleanup(fs_info->fs_root);
+		up_read(&fs_info->cleanup_work_sem);
+	}
+
 	return tree_root;
 
 fail_trans_kthread:

fs/btrfs/inode.c

@@ -3797,12 +3797,6 @@ struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
 
 	if (location.type == BTRFS_INODE_ITEM_KEY) {
 		inode = btrfs_iget(dir->i_sb, &location, root);
-		if (unlikely(root->clean_orphans) &&
-		    !(inode->i_sb->s_flags & MS_RDONLY)) {
-			down_read(&root->fs_info->cleanup_work_sem);
-			btrfs_orphan_cleanup(root);
-			up_read(&root->fs_info->cleanup_work_sem);
-		}
 		return inode;
 	}