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Date:   Sat, 22 Jul 2023 13:23:01 +1200
From:   Herbert Xu <herbert@gondor.apana.org.au>
To:     Tom Zanussi <tom.zanussi@linux.intel.com>
Cc:     davem@davemloft.net, fenghua.yu@intel.com, vkoul@kernel.org,
        dave.jiang@intel.com, tony.luck@intel.com,
        wajdi.k.feghali@intel.com, james.guilford@intel.com,
        kanchana.p.sridhar@intel.com, vinodh.gopal@intel.com,
        giovanni.cabiddu@intel.com, linux-kernel@vger.kernel.org,
        linux-crypto@vger.kernel.org, dmaengine@vger.kernel.org
Subject: Re: [PATCH v7 12/14] crypto: iaa - Add support for deflate-iaa
 compression algorithm
Message-ID: <ZLsvdS6NbaetDFe1@gondor.apana.org.au>
References: <20230710190654.299639-1-tom.zanussi@linux.intel.com>
 <20230710190654.299639-13-tom.zanussi@linux.intel.com>
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On Mon, Jul 10, 2023 at 02:06:52PM -0500, Tom Zanussi wrote:
>
> Because the IAA hardware has a 4k history-window limitation, only
> buffers <= 4k, or that have been compressed using a <= 4k history
> window, are technically compliant with the deflate spec, which allows
> for a window of up to 32k.  Because of this limitation, the IAA fixed
> mode deflate algorithm is given its own algorithm name, 'deflate-iaa'.

So compressed results produced by this can always be decompressed
by the generic algorithm, right?

If it's only when you decompress that you may encounter failures,
then I suggest that we still use the same algorithm name, but fall
back at run-time if the result cannot be decompressed by the
hardware.  Is it possible to fail gracefully and then retry the
decompression in this case?

Thanks,
-- 
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