Re: [PATCH v7 12/14] crypto: iaa - Add support for deflate-iaa compression algorithm

Tom Zanussi
2023-07-22T17:14:36Z

On Sat, 2023-07-22 at 13:23 +1200, Herbert Xu wrote:
> 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?
>

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?
>

Yeah, I think that should be possible. I'll try it out and add it to
the next version. Thanks for the suggestion!

Tom

> Thanks,