linux-kernel - Re: [PATCH 2/2] crypto: caam: Use common error handling code in four functions

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Message-ID: <VI1PR0402MB3342F9E0700AA3A7CC20D8DC98F40@VI1PR0402MB3342.eurprd04.prod.outlook.com>
Date:   Thu, 15 Feb 2018 08:03:24 +0000
From:   Horia Geantă <horia.geanta@....com>
To:     SF Markus Elfring <elfring@...rs.sourceforge.net>,
        "linux-crypto@...r.kernel.org" <linux-crypto@...r.kernel.org>,
        Aymen Sghaier <aymen.sghaier@....com>,
        "David S. Miller" <davem@...emloft.net>,
        Herbert Xu <herbert@...dor.apana.org.au>
CC:     LKML <linux-kernel@...r.kernel.org>,
        "kernel-janitors@...r.kernel.org" <kernel-janitors@...r.kernel.org>
Subject: Re: [PATCH 2/2] crypto: caam: Use common error handling code in four
 functions

On 2/14/2018 8:32 PM, SF Markus Elfring wrote:
> From: Markus Elfring <elfring@...rs.sourceforge.net>
> Date: Wed, 14 Feb 2018 19:14:49 +0100
> 
> Add jump targets so that a bit of exception handling can be better reused
> at the end of these functions.
> 
> Signed-off-by: Markus Elfring <elfring@...rs.sourceforge.net>
[snip]
> @@ -1096,6 +1092,7 @@ static int ahash_digest(struct ahash_request *req)
>  	if (!ret) {
>  		ret = -EINPROGRESS;
>  	} else {
> +unmap_hash:
>  		ahash_unmap(jrdev, edesc, req, digestsize);
>  		kfree(edesc);
>  	}
> 
I understand jumps are a necessary evil for dealing with shortcomings of C,
however please avoid jumping in an if/else branch.

Code could be rewritten as:

  	if (!ret)
  		return -EINPROGRESS;

unmap_hash:
  	ahash_unmap(jrdev, edesc, req, digestsize);
  	kfree(edesc);

Thanks,
Horia