Re: [RFC PATCH 00/21] crypto: consolidate and clean up compression APIs

Herbert Xu
2023-07-28T09:56:25Z

On Tue, Jul 18, 2023 at 02:58:26PM +0200, Ard Biesheuvel wrote:
>
> Patch #2 removes the support for on-the-fly allocation of destination
> buffers and scatterlists from the Intel QAT driver. This is never used,
> and not even implemented by all drivers (the HiSilicon ZIP driver does
> not support it). The diffstat of this patch makes a good case why the
> caller should be in charge of allocating the memory, not the driver.

The implementation in qat may not be optimal, but being able to
allocate memory in the algorithm is a big plus for IPComp at least.

Being able to allocate memory page by page as you decompress
means that:

1. We're not affected by memory fragmentation.
2. We don't waste memory by always allocating for the worst case.

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