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Date:   Mon, 26 Jun 2023 17:52:41 +0800
From:   Herbert Xu <herbert@gondor.apana.org.au>
To:     Ard Biesheuvel <ardb@kernel.org>
Cc:     David Howells <dhowells@redhat.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Roberto Sassu <roberto.sassu@huaweicloud.com>,
        Eric Biggers <ebiggers@kernel.org>,
        Stefan Berger <stefanb@linux.ibm.com>,
        Mimi Zohar <zohar@linux.ibm.com>, dmitry.kasatkin@gmail.com,
        Jarkko Sakkinen <jarkko@kernel.org>, keyrings@vger.kernel.org,
        Linux Crypto Mailing List <linux-crypto@vger.kernel.org>
Subject: Re: [v2 PATCH 0/5] crypto: Add akcipher interface without SGs
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On Mon, Jun 26, 2023 at 11:21:20AM +0200, Ard Biesheuvel wrote:
>
> As I asked before, could we do the same for the acomp API? The only
> existing user blocks on the completion, and the vast majority of
> implementations is software only.

We already have scomp.  It's not exported so we could export it.

However, compression is quite different because it was one of the
original network stack algorithms (IPcomp).  So SG will always be
needed.

In fact, if anything SG fits quite well with decompression because
it would allow us to allocate pages as we go, avoiding the need
to allocate a large chunk of memory at the start as we do today.

We don't make use of that ability today but that's something that
I'd like to address.

Cheers,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt