Re: [PATCH 3/4] btrfs-progs: map-logical: loosen the required trees to open the filesystem

[Nikolay Borisov <nborisov@suse.com>]

On 12.08.21 г. 8:35, Qu Wenruo wrote:
> For btrfs-map-logical, it only requires chunk tree to do the
> logicla->physical mapping.
> 
> All othe trees are not really needed.
> 
> Loosen the required trees to make btrfs-map-logical to work better on
> corrupted fs.
> 
> Signed-off-by: Qu Wenruo <wqu@suse.com>
> ---
>  btrfs-map-logical.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/btrfs-map-logical.c b/btrfs-map-logical.c
> index 21f00fa20ce8..9f119d08bad8 100644
> --- a/btrfs-map-logical.c
> +++ b/btrfs-map-logical.c
> @@ -261,7 +261,8 @@ int main(int argc, char **argv)
>  	radix_tree_init();
>  	cache_tree_init(&root_cache);
>  
> -	root = open_ctree(dev, 0, 0);
> +	root = open_ctree(dev, 0, OPEN_CTREE_PARTIAL |
> +				  OPEN_CTREE_NO_BLOCK_GROUPS);

nit: OPEN_CTREE_PARTIAL implies ignoring error when opening the csum and
extent tress, since those trees are opened via
setup_root_or_create_block. This tells me that
OPEN_CTREE_NO_BLOCK_GROUPS is redundant and can be removed and replaced
with simply OPEN_CTREE_PARTIAL.

>  	if (!root) {
>  		fprintf(stderr, "Open ctree failed\n");
>  		free(output_file);
>