Re: [PATCH 07/10] crypto: Use ARCH_DMA_MINALIGN instead of ARCH_KMALLOC_MINALIGN

Catalin Marinas
2022-04-18T09:19:31Z

On Mon, Apr 18, 2022 at 04:37:17PM +0800, Herbert Xu wrote:
> On Sun, Apr 17, 2022 at 05:30:27PM +0100, Catalin Marinas wrote:
> >
> > Do you mean as per Ard's proposal here:
> >
> > https://lore.kernel.org/r/CAMj1kXH0x5Va7Wgs+mU1ONDwwsazOBuN4z4ihVzO2uG-n41Kbg@mail.gmail.com
> >
> > struct crypto_request {
> > union {
> > struct {
> > ... fields ...
> > };
> > u8 __padding[ARCH_DMA_MINALIGN];
> > };
> > void __ctx[] __aligned(CRYPTO_MINALIGN);
> > };
> >
> > If CRYPTO_MINALIGN is lowered to, say, 8 (to be the same as lowest
> > ARCH_KMALLOC_MINALIGN), the __alignof__(req->__ctx) would be 8.
> > Functions like crypto_tfm_ctx_alignment() will return 8 when what you
> > need is 128. We can change those functions to return ARCH_DMA_MINALIGN
> > instead or always bump cra_alignmask to ARCH_DMA_MINALIGN-1.
>
> OK, at this point I think we need to let the code do the talking :)
>
> I've seen Ard's patches already and I think I understand what your
> needs are. So let me whip up some code to show you guys what I
> think needs to be done.
>
> Please bear with me for a few days.

Thanks Herbert, that's great. Whenever you have time, I'll be busy this
week with collecting arm64 patches for the upcoming merging window
anyway.

--
Catalin