RE: [PATCH v11 18/24] crypto: acomp - Add crypto_acomp_batch_size() to get an algorithm's batch-size.

[Sridhar, Kanchana P]

> -----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,
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