Btrfs: add disk ioctl, mostly working

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 3a15943ea8ed..8740752f3845 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -116,7 +116,13 @@ int btrfs_commit_tree_roots(struct btrfs_trans_handle *trans,
         struct btrfs_fs_info *fs_info = root->fs_info;
         struct btrfs_root *tree_root = fs_info->tree_root;
         struct btrfs_root *extent_root = fs_info->extent_root;
+        struct btrfs_root *dev_root = fs_info->dev_root;
 
+        if (btrfs_super_device_root(fs_info->disk_super) !=
+            bh_blocknr(dev_root->node)) {
+                btrfs_set_super_device_root(fs_info->disk_super,
+                                            bh_blocknr(dev_root->node));
+        }
         while(1) {
                 old_extent_block = btrfs_root_blocknr(&extent_root->root_item);
                 if (old_extent_block == bh_blocknr(extent_root->node))