Re: [PATCH v2 1/8] crypto: support (de)compression API that doesn't require tfm object

[Herbert Xu <herbert@gondor.apana.org.au>]

On Thu, Aug 20, 2015 at 04:52:17PM +0900, Joonsoo Kim wrote:
> 
> Hmm... I guess there is no problem. crypto_alg object fetched by
> crypto_get_comp() introduced in this patch could be hardware device
> algorithm which is same one that we can eventually fetch from tfm object.
> So, this approach would correctly track the crypto_alg regardless
> it is a hardware one or not. If there is some dependency between
> algorithm and tfm, it can't support _noctx API. Am I missing
> something?

Your approach limits what hardware devices we can support in
future.  It is fairly common for hardware drivers to only allocate
resources when a tfm is created.  With your tfmless interface,
the driver would have to unconditionally allocate resources.

It is essentially a global tfm without the tfm.

> Yes, I thought this way before, but, current way is much simpler so
> I try it first. If it is not acceptable, I will implement this
> approach.

Please go with a global tfm.

Thanks,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
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