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

Ard Biesheuvel
2023-07-28T09:57:56Z

On Fri, 28 Jul 2023 at 11:56, Herbert Xu <herbert@gondor.apana.org.au> wrote:
>
> 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.
>

So will IPcomp be able to simply assign those pages to the SKB afterwards?