Re: [PATCH v3 12/14] btrfs: Use btrfs_for_each_slot in btrfs_unlink_all_paths

[Josef Bacik <josef@toxicpanda.com>]

On Wed, Mar 02, 2022 at 05:48:27PM +0100, Gabriel Niebler wrote:
> This function can be simplified by refactoring to use the new iterator macro.
> 
> No functional changes.
> 
> Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
> Signed-off-by: Gabriel Niebler <gniebler@suse.com>
> ---
>  fs/btrfs/send.c | 36 +++++++++++++-----------------------
>  1 file changed, 13 insertions(+), 23 deletions(-)
> 
> diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
> index 7e40c73bb912..af3668279875 100644
> --- a/fs/btrfs/send.c
> +++ b/fs/btrfs/send.c
> @@ -6119,8 +6119,11 @@ static int btrfs_unlink_all_paths(struct send_ctx *sctx)
>  {
>  	LIST_HEAD(deleted_refs);
>  	struct btrfs_path *path;
> +	struct btrfs_root *root = sctx->parent_root;
>  	struct btrfs_key key;
> +	struct btrfs_key found_key;
>  	struct parent_paths_ctx ctx;
> +	int iter_ret = 0;
>  	int ret;
>  
>  	path = alloc_path_for_send();
> @@ -6130,39 +6133,26 @@ static int btrfs_unlink_all_paths(struct send_ctx *sctx)
>  	key.objectid = sctx->cur_ino;
>  	key.type = BTRFS_INODE_REF_KEY;
>  	key.offset = 0;
> -	ret = btrfs_search_slot(NULL, sctx->parent_root, &key, path, 0, 0);
> -	if (ret < 0)
> -		goto out;
>  
>  	ctx.refs = &deleted_refs;
>  	ctx.sctx = sctx;
>  
> -	while (true) {
> -		struct extent_buffer *eb = path->nodes[0];
> -		int slot = path->slots[0];
> -
> -		if (slot >= btrfs_header_nritems(eb)) {
> -			ret = btrfs_next_leaf(sctx->parent_root, path);
> -			if (ret < 0)
> -				goto out;
> -			else if (ret > 0)
> -				break;
> -			continue;
> -		}
> -
> -		btrfs_item_key_to_cpu(eb, &key, slot);
> -		if (key.objectid != sctx->cur_ino)
> +	btrfs_for_each_slot(root, &key, &found_key, path, iter_ret) {
> +		if (found_key.objectid != key.objectid)
>  			break;
> -		if (key.type != BTRFS_INODE_REF_KEY &&
> -		    key.type != BTRFS_INODE_EXTREF_KEY)
> +		if (found_key.type != key.type &&
> +		    found_key.type != BTRFS_INODE_EXTREF_KEY)
>  			break;
>  
> -		ret = iterate_inode_ref(sctx->parent_root, path, &key, 1,
> +		ret = iterate_inode_ref(root, path, &key, 1,
>  					record_parent_ref, &ctx);

This patch is causing btrfs/168 to fail, this should be &found_key, not &key.
Thanks,

Josef