> -----Original Message-----
> From: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
> Sent: Thursday, August 14, 2025 10:29 PM
> To: Sridhar, Kanchana P <kanchana.p.sridhar@xxxxxxxxx>
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> Subject: Re: [PATCH v11 18/24] crypto: acomp - Add
> crypto_acomp_batch_size() to get an algorithm's batch-size.
>
> On Thu, Jul 31, 2025 at 09:36:36PM -0700, Kanchana P Sridhar wrote:
> >
> > diff --git a/include/crypto/internal/acompress.h
> b/include/crypto/internal/acompress.h
> > index ffffd88bbbad3..2325ee18e7a10 100644
> > --- a/include/crypto/internal/acompress.h
> > +++ b/include/crypto/internal/acompress.h
> > @@ -28,6 +28,8 @@
> > *
> > * @compress: Function performs a compress operation
> > * @decompress: Function performs a de-compress operation
> > + * @get_batch_size: Maximum batch-size for batching
> compress/decompress
> > + * operations.
> > * @init: Initialize the cryptographic transformation object.
> > * This function is used to initialize the cryptographic
> > * transformation object. This function is called only once at
> > @@ -46,6 +48,7 @@
> > struct acomp_alg {
> > int (*compress)(struct acomp_req *req);
> > int (*decompress)(struct acomp_req *req);
> > + unsigned int (*get_batch_size)(void);
>
> I can't imagine a situation where this needs to be dynamic.
> Please just make it a static value rather than a callback function.
Hi Herbert,
I am not sure I understand.. Kernel users such as zswap/zram need to query
the algorithm to get the maximum supported batch-size so they can allocate
resources for dst buffers. The get_batch_size() callback and associated
crypto_acomp_batch_size() wrapper help accomplish this.
Can you please clarify what you mean by "static value"?
Thanks,
Kanchana
>
> Thanks,
> --
> Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
> Home Page: http://gondor.apana.org.au/~herbert/
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