Btrfs: Only delete roots from sysfs when they were added to sysfs

Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 0338f8f..87daed6 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -795,7 +795,8 @@
 {
 	radix_tree_delete(&fs_info->fs_roots_radix,
 			  (unsigned long)root->root_key.objectid);
-	btrfs_sysfs_del_root(root);
+	if (root->in_sysfs)
+		btrfs_sysfs_del_root(root);
 	if (root->inode)
 		iput(root->inode);
 	if (root->node)