[PATCH v4 17/22] btrfs-progs: add a btrfs_delete_and_free_root helper

[Josef Bacik <josef@toxicpanda.com>]

The free space tree code already does this, but we need it for cleaning
up per block group roots.  Abstract this code out into a helper so that
we can use it in multiple places in the future.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 kernel-shared/disk-io.c         | 25 +++++++++++++++++++++++++
 kernel-shared/disk-io.h         |  2 ++
 kernel-shared/free-space-tree.c | 24 +++---------------------
 3 files changed, 30 insertions(+), 21 deletions(-)

diff --git a/kernel-shared/disk-io.c b/kernel-shared/disk-io.c
index 38118e1d..83977cec 100644
--- a/kernel-shared/disk-io.c
+++ b/kernel-shared/disk-io.c
@@ -2368,6 +2368,31 @@ int btrfs_set_buffer_uptodate(struct extent_buffer *eb)
 	return set_extent_buffer_uptodate(eb);
 }
 
+int btrfs_delete_and_free_root(struct btrfs_trans_handle *trans,
+			       struct btrfs_root *root)
+{
+	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct btrfs_root *tree_root = fs_info->tree_root;
+	int ret;
+
+	ret = btrfs_del_root(trans, tree_root, &root->root_key);
+	if (ret)
+		return ret;
+
+	list_del(&root->dirty_list);
+	ret = clean_tree_block(root->node);
+	if (ret)
+		return ret;
+	ret = btrfs_free_tree_block(trans, root, root->node, 0, 1);
+	if (ret)
+		return ret;
+	rb_erase(&root->rb_node, &fs_info->global_roots_tree);
+	free_extent_buffer(root->node);
+	free_extent_buffer(root->commit_root);
+	kfree(root);
+	return 0;
+}
+
 struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
 				     struct btrfs_fs_info *fs_info,
 				     u64 objectid)
diff --git a/kernel-shared/disk-io.h b/kernel-shared/disk-io.h
index 4f58cad1..6a64b620 100644
--- a/kernel-shared/disk-io.h
+++ b/kernel-shared/disk-io.h
@@ -214,6 +214,8 @@ int btrfs_fs_roots_compare_roots(struct rb_node *node1, struct rb_node *node2);
 struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
 				     struct btrfs_fs_info *fs_info,
 				     u64 objectid);
+int btrfs_delete_and_free_root(struct btrfs_trans_handle *trans,
+			       struct btrfs_root *root);
 struct btrfs_root *btrfs_csum_root(struct btrfs_fs_info *fs_info, u64 bytenr);
 struct btrfs_root *btrfs_extent_root(struct btrfs_fs_info *fs_inf, u64 bytenr);
 struct btrfs_root *btrfs_global_root(struct btrfs_fs_info *fs_info,
diff --git a/kernel-shared/free-space-tree.c b/kernel-shared/free-space-tree.c
index a82865d3..0a13b1d6 100644
--- a/kernel-shared/free-space-tree.c
+++ b/kernel-shared/free-space-tree.c
@@ -1257,27 +1257,9 @@ int btrfs_clear_free_space_tree(struct btrfs_fs_info *fs_info)
 	if (ret)
 		goto abort;
 
-	ret = btrfs_del_root(trans, tree_root, &free_space_root->root_key);
-	if (ret)
-		goto abort;
-
-	list_del(&free_space_root->dirty_list);
-
-	ret = clean_tree_block(free_space_root->node);
-	if (ret)
-		goto abort;
-	ret = btrfs_free_tree_block(trans, free_space_root,
-				    free_space_root->node, 0, 1);
-	if (ret)
-		goto abort;
-
-	rb_erase(&free_space_root->rb_node, &fs_info->global_roots_tree);
-	free_extent_buffer(free_space_root->node);
-	free_extent_buffer(free_space_root->commit_root);
-	kfree(free_space_root);
-
-	ret = btrfs_commit_transaction(trans, tree_root);
-
+	ret = btrfs_delete_and_free_root(trans, free_space_root);
+	if (!ret)
+		ret = btrfs_commit_transaction(trans, tree_root);
 abort:
 	return ret;
 }
-- 
2.26.3