RE: [PATCH v9 10/19] crypto: acomp - New interfaces to facilitate batching support in acomp & drivers.

[Sridhar, Kanchana P]

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> Sent: Friday, May 16, 2025 5:46 PM
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> Subject: Re: [PATCH v9 10/19] crypto: acomp - New interfaces to facilitate
> batching support in acomp & drivers.
> 
> On Fri, May 16, 2025 at 07:17:36PM +0000, Sridhar, Kanchana P wrote:
> >
> > It appears acomp_do_req_chain() and acomp_reqchain_finish() compress
> the
> 
> That's the fallback path.
> 
> A hardware driver capable of batching is supposed to declare the
> bit in cra_flags that bypasses the fallback.

IIUC, are you referring to the "CRYPTO_ALG_REQ_SEG" cra_flags bit?

If a hardware driver sets this bit, then crypto_acomp_req_seg() will
return "true" in crypto_acomp_compress() and the folio will be compressed
as one unit by the call to " crypto_acomp_reqtfm(req)->compress(req)":

int crypto_acomp_compress(struct acomp_req *req)
{
	struct crypto_acomp *tfm = crypto_acomp_reqtfm(req);

	if (acomp_req_on_stack(req) && acomp_is_async(tfm))
		return -EAGAIN;
	if ((crypto_acomp_req_virt(tfm) || acomp_request_issg(req)) &&
	    (crypto_acomp_req_seg(tfm) || !acomp_request_isunit(req)))
		return crypto_acomp_reqtfm(req)->compress(req);
	return acomp_do_req_chain(req, true);
}
EXPORT_SYMBOL_GPL(crypto_acomp_compress);

If so, then we still have not addressed the issue highlighted in [1], please
correct me if I am wrong:

[1]: https://lore.kernel.org/all/CAKEwX=PRzZEYOuTECjjqYbUDXUjMzOc-R5s14-iX8qevDxGBpA@xxxxxxxxxxxxxx/

Can you please advise?

Thanks,
Kanchana