Re: [PATCH 2/4] btrfs: Consolidate retval checking of core btree functions

[Qu Wenruo <quwenruo.btrfs@gmx.com>]

On 2018/12/17 下午4:36, Nikolay Borisov wrote:
> Core btree functions in btrfs generally return 0 for error

Isn't 0 for key found? It's <0 for error.

 and 1 in case
> the sought item cannot be found. Consolidate the checks for those
> conditions in one 'if () {} else if () {}' struct rather than 2 separate
> 'if () {}' statements. This emphasizes that the handling code pertains
> to a single function. No functional changes.
> 
> Signed-off-by: Nikolay Borisov <nborisov@suse.com>
The code itself is OK, but the commit message is really confusing.

Thanks,
Qu

> ---
>  fs/btrfs/inode.c | 7 ++-----
>  1 file changed, 2 insertions(+), 5 deletions(-)
> 
> diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
> index fe25f66a98d9..511d3b314af2 100644
> --- a/fs/btrfs/inode.c
> +++ b/fs/btrfs/inode.c
> @@ -6801,9 +6801,7 @@ struct extent_map *btrfs_get_extent(struct btrfs_inode *inode,
>  	if (ret < 0) {
>  		err = ret;
>  		goto out;
> -	}
> -
> -	if (ret != 0) {
> +	} else if (ret > 0) {
>  		if (path->slots[0] == 0)
>  			goto not_found;
>  		path->slots[0]--;
> @@ -6853,8 +6851,7 @@ struct extent_map *btrfs_get_extent(struct btrfs_inode *inode,
>  			if (ret < 0) {
>  				err = ret;
>  				goto out;
> -			}
> -			if (ret > 0)
> +			} else if (ret > 0)
>  				goto not_found;
>  			leaf = path->nodes[0];
>  		}
>