Btrfs: create UUID tree if required
This tree is not created by mkfs.btrfs. Therefore when a filesystem
is mounted writable and the UUID tree does not exist, this tree is
created if required. The tree is also added to the fs_info structure
and initialized, but this commit does not yet read or write UUID tree
elements.
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 306547b..e084218 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -3429,6 +3429,32 @@
return 0;
}
+int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_trans_handle *trans;
+ struct btrfs_root *tree_root = fs_info->tree_root;
+ struct btrfs_root *uuid_root;
+
+ /*
+ * 1 - root node
+ * 1 - root item
+ */
+ trans = btrfs_start_transaction(tree_root, 2);
+ if (IS_ERR(trans))
+ return PTR_ERR(trans);
+
+ uuid_root = btrfs_create_tree(trans, fs_info,
+ BTRFS_UUID_TREE_OBJECTID);
+ if (IS_ERR(uuid_root)) {
+ btrfs_abort_transaction(trans, tree_root,
+ PTR_ERR(uuid_root));
+ return PTR_ERR(uuid_root);
+ }
+
+ fs_info->uuid_root = uuid_root;
+
+ return btrfs_commit_transaction(trans, tree_root);
+}
/*
* shrinking a device means finding all of the device extents past
* the new size, and then following the back refs to the chunks.