Re: [PATCH v11 00/24] zswap compression batching with optimized iaa_crypto driver

[Herbert Xu]

On Tue, Aug 26, 2025 at 04:09:45AM +0000, Sridhar, Kanchana P wrote:
> 
> Thanks Herbert. Just want to make sure I understand this. Are you
> referring to replacing sg_set_page() for the input with sg_set_folio()?
> We have to pass in a scatterlist for the acomp_req->src..

I'm talking about acomp_request_set_src_folio.  You can pass just
a portion of a folio by specifying an offset and a length.

>         for (i = 0; i < nr_pages; i += nr_comps) {
>                 for_each_sg(acomp_ctx->sg_inputs->sgl, sg, nr_comps, k)
>                         sg_set_folio(sg, folio, PAGE_SIZE, (start + k + i) * PAGE_SIZE);
> 
>                 /*                                                                                                                        
>                  * We need PAGE_SIZE * 2 here since there maybe over-compression case,                                                    
>                  * and hardware-accelerators may won't check the dst buffer size, so                                                      
>                  * giving the dst buffer with enough length to avoid buffer overflow.                                                     
>                  */
>                 for_each_sg(acomp_ctx->sg_outputs->sgl, sg, nr_comps, k)
>                         sg_set_buf(sg, acomp_ctx->buffers[k], PAGE_SIZE * 2);
>
>                 acomp_request_set_params(acomp_ctx->req,
>                                          acomp_ctx->sg_inputs->sgl,
>                                          acomp_ctx->sg_outputs->sgl,
>                                          nr_comps * PAGE_SIZE,
>                                          nr_comps * PAGE_SIZE);

I meant something more like:

		acomp_request_set_src_folio(req, folio, start_offset,
					    nr_comps * PAGE_SIZE);
		acomp_request_set_dst_sg(req, acomp_ctx_sg_outputs->sgl,
					 nr_comps * PAGE_SIZE);
		acomp_request_set_unit_size(req, PAGE_SIZE);

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