Re: [PATCH] btrfs: Remove err variable from btrfs_get_extent

[David Sterba <dsterba@suse.cz>]

On Mon, Aug 03, 2020 at 12:58:46PM +0300, Nikolay Borisov wrote:
> @@ -6713,32 +6708,33 @@ struct extent_map *btrfs_get_extent(struct btrfs_inode *inode,
>  		goto insert;
>  	}
>  not_found:
> +	ret = 0;
>  	em->start = start;
>  	em->orig_start = start;
>  	em->len = len;
>  	em->block_start = EXTENT_MAP_HOLE;
>  insert:
> +	ret = 0;

It's not necessary to set ret = 0 in not_found, there's no conditional
until this line keeping it for 'insert' should be sufficient.

>  	btrfs_release_path(path);
>  	if (em->start > start || extent_map_end(em) <= start) {
>  		btrfs_err(fs_info,
>  			  "bad extent! em: [%llu %llu] passed [%llu %llu]",
>  			  em->start, em->len, start, len);
> -		err = -EIO;
> +		ret = -EIO;
>  		goto out;
>  	}
> 
> -	err = 0;
>  	write_lock(&em_tree->lock);
> -	err = btrfs_add_extent_mapping(fs_info, em_tree, &em, start, len);
> +	ret = btrfs_add_extent_mapping(fs_info, em_tree, &em, start, len);
>  	write_unlock(&em_tree->lock);
>  out:
>  	btrfs_free_path(path);
> 
>  	trace_btrfs_get_extent(root, inode, em);
> 
> -	if (err) {
> +	if (ret) {
>  		free_extent_map(em);
> -		return ERR_PTR(err);
> +		return ERR_PTR(ret);
>  	}
>  	return em;
>  }
> --
> 2.17.1