Re: [PATCH 3/3] btrfs: clean search for device item in finish sprout

[David Sterba <dsterba@suse.cz>]

On Wed, Aug 21, 2019 at 05:26:34PM +0800, Anand Jain wrote:
> No need to btrfs_item_key_to_cpu() as we continue to next leaf. Also keep
> the found_key and search key separate.
> 
> Signed-off-by: Anand Jain <anand.jain@oracle.com>
> ---
>  fs/btrfs/volumes.c | 9 ++++-----
>  1 file changed, 4 insertions(+), 5 deletions(-)
> 
> diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
> index a343aa9cf5ba..1db06894aee6 100644
> --- a/fs/btrfs/volumes.c
> +++ b/fs/btrfs/volumes.c
> @@ -2471,6 +2471,7 @@ static int btrfs_finish_sprout(struct btrfs_trans_handle *trans)
>  	struct extent_buffer *leaf;
>  	struct btrfs_dev_item *dev_item;
>  	struct btrfs_device *device;
> +	struct btrfs_key found_key;

The declaration should be in the scope of use, ie. inside the while
loop.

>  	struct btrfs_key key;
>  	u8 fs_uuid[BTRFS_FSID_SIZE];
>  	u8 dev_uuid[BTRFS_UUID_SIZE];
> @@ -2498,15 +2499,13 @@ static int btrfs_finish_sprout(struct btrfs_trans_handle *trans)
>  				break;
>  			if (ret < 0)
>  				goto error;
> -			leaf = path->nodes[0];
> -			btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
>  			btrfs_release_path(path);
>  			continue;
>  		}
>  
> -		btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
> -		if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID ||
> -		    key.type != BTRFS_DEV_ITEM_KEY)
> +		btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
> +		if (found_key.objectid != BTRFS_DEV_ITEMS_OBJECTID ||
> +		    found_key.type != BTRFS_DEV_ITEM_KEY)
>  			break;
>  
>  		dev_item = btrfs_item_ptr(leaf, path->slots[0],
> -- 
> 2.21.0 (Apple Git-120)