btrfs: free the reloc_control in a consistent way

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 reloc 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>
Reviewed-by: David Sterba <dsterba@suse.com>
[ use rbtree_postorder_for_each_entry_safe ]
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index 631f940..a0c8f79 100644 (file)
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -4202,6 +4202,18 @@ 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)
+               kfree(node);
+
+       kfree(rc);
+}
+
 /*
  * Print the block group being relocated
  */
@@ -4346,7 +4358,7 @@ out:
                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;
 }
 
@@ -4522,7 +4534,7 @@ out_clean:
                err = ret;
 out_unset:
        unset_reloc_control(rc);
-       kfree(rc);
+       free_reloc_control(rc);
 out:
        if (!list_empty(&reloc_roots))
                free_reloc_roots(&reloc_roots);