[PATCH 4/8] btrfs: free the reloc_control in a consistent way

[Josef Bacik <josef@toxicpanda.com>]

If we have an error while processing the reloc roots we could leak roots
that were added to rc->reloc_roots before we hit the error.  We could
have also not removed the reloct tree mapping from our rb_tree, so clean
up any remaining nodes in the reloc root rb_tree.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/relocation.c | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index c496f8ed8c7e..721d049ff2b5 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -4387,6 +4387,20 @@ static struct reloc_control *alloc_reloc_control(struct btrfs_fs_info *fs_info)
 	return rc;
 }
 
+static void free_reloc_control(struct reloc_control *rc)
+{
+	struct mapping_node *node, *tmp;
+
+	free_reloc_roots(&rc->reloc_roots);
+	rbtree_postorder_for_each_entry_safe(node, tmp,
+					     &rc->reloc_root_tree.rb_root,
+					     rb_node) {
+		rb_erase(&node->rb_node, &rc->reloc_root_tree.rb_root);
+		kfree(node);
+	}
+	kfree(rc);
+}
+
 /*
  * Print the block group being relocated
  */
@@ -4531,7 +4545,7 @@ int btrfs_relocate_block_group(struct btrfs_fs_info *fs_info, u64 group_start)
 		btrfs_dec_block_group_ro(rc->block_group);
 	iput(rc->data_inode);
 	btrfs_put_block_group(rc->block_group);
-	kfree(rc);
+	free_reloc_control(rc);
 	return err;
 }
 
@@ -4708,7 +4722,7 @@ int btrfs_recover_relocation(struct btrfs_root *root)
 out_unset:
 	unset_reloc_control(rc);
 out_free:
-	kfree(rc);
+	free_reloc_control(rc);
 out:
 	if (!list_empty(&reloc_roots))
 		free_reloc_roots(&reloc_roots);
-- 
2.24.1