[PATCH] UBIFS: add a comment in key.h for unused parameter

[Artem Bityutskiy]

On Sun, 2015-12-20 at 11:25 +0800, Dongsheng Yang wrote:
> Add a comment in key.h to explain why we keep an unused
> parameter in key helpers.
> 
> Signed-off-by: Dongsheng Yang <yangds.fnst at cn.fujitsu.com>
> ---
>  fs/ubifs/key.h | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/fs/ubifs/key.h b/fs/ubifs/key.h
> index 92a8491..dce72c4 100644
> --- a/fs/ubifs/key.h
> +++ b/fs/ubifs/key.h
> @@ -34,6 +34,12 @@
>   * node. We use "r5" hash borrowed from reiserfs.
>   */
>  
> +/*
> + * Lot's of the key helpers require a struct ubifs_info *c as the
> first parameter.
> + * But we are not using it at all currently. That's designed for
> scalability for
> + * different c->key_format. But right now, there is only one key
> type, UBIFS_SIMPLE_KEY_FMT.
> + */

I think word "scalability" is not a perfect fit here. Just say for
future extensions, or something like this. Scalability is a bit
confusing.