Re: [PATCH v2] crypto: xxhash - Implement xxhash support

[Eric Biggers <ebiggers@kernel.org>]

On Tue, May 28, 2019 at 03:14:51PM +0300, Nikolay Borisov wrote:
> xxhash is currently implemented as a self-contained module in /lib.
> This patch enables that module to be used as part of the generic kernel
> crypto framework. It adds a simple wrapper to the 64bit version.
> 

Thanks, this looks a lot better.  A couple minor comments below.

> +static int xxhash64_init(struct shash_desc *desc)
> +{
> +	struct xxhash64_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm);
> +	struct xxhash64_desc_ctx *dctx = shash_desc_ctx(desc);
> +
> +	xxh64_reset(&dctx->xxhstate, tctx->seed);
> +
> +	return 0;
> +}
> +
> +static int xxhash64_setkey(struct crypto_shash *tfm, const u8 *key,
> +			 unsigned int keylen)
> +{
> +	struct xxhash64_tfm_ctx *tctx = crypto_shash_ctx(tfm);
> +
> +	if (keylen != sizeof(tctx->seed)) {
> +		crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
> +		return -EINVAL;
> +	}
> +	tctx->seed = get_unaligned_le64(key);
> +	return 0;
> +}

Can you please move xxhash64_setkey() to before xxhash64_init() to match the
order in which the functions get called?

Sometimes people get confused and think that crypto_shash_init() comes before
crypto_shash_setkey(), so it's helpful to keep definitions in order.

> +module_init(xxhash_mod_init);

Can you change this to subsys_initcall?  We're using subsys_initcall for the
generic implementations of crypto algorithms now, so that when other
implementations (e.g. assembly language implementations) are added, the crypto
self-tests can compare them to the generic implementations.

Thanks,

- Eric