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Date: Tue, 30 Apr 2024 12:04:47 +0900
From: Sergey Senozhatsky <senozhatsky@chromium.org>
To: Herbert Xu <herbert@gondor.apana.org.au>,
	"David S. Miller" <davem@davemloft.net>
Cc: linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [RFC] crypto: passing configuration parameters to comp algos
Message-ID: <20240430030447.GE14947@google.com>
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Hi,

	We'd like to be able to pass algorithm-specific parameters to
comp backends. As of this moment, crypto usees hard-coded default
values and does not permit any run-time algorithm configuration,
which in some cases simply disables the most interesting functionality.
E.g. zstd can be configured to use a pre-trained (in the user-space)
compression dictionary, which significantly changes algorithms
characteristics. Another, obvious and trivial example, is algorithms
compression level.

The problem is that we need to pass params to cra_init() function,
because for some algorithms that's the only place where configuration
can take place (e.g. zstd). Changing cra_init() to accept additional
`struct crypto_comp_params` looks to be a little intrusive so before
I write any patches I'd like to hear your thoughts.