Re: [PATCH 1/4] block: use ARCH_KMALLOC_MINALIGN as the default dma pad mask

FUJITA Tomonori
2008-05-20T13:25:25Z

On Tue, 20 May 2008 17:38:20 +0800
Herbert Xu <herbert@gondor.apana.org.au> wrote:

> On Tue, May 20, 2008 at 02:31:29AM -0700, Andrew Morton wrote:
> >
> > So here you're using it for "dma aligment" whereas crypto is using it
> > (or ARCH_SLAB_MINALIGN!) for "cpu 64-bit alignment".
>
> No the 64-bit alignment is just an example. The purpose of
> CRYPTO_MINALIGN is pretty much the same as ARCH_KMALLOC_MINALIGN,
> i.e., the minimum alignment guaranteed by kmalloc. The only
> reason it exists is because ARCH_KMALLOC_MINALIGN isn't defined
> on all platforms.

struct ablkcipher_request {
struct crypto_async_request base;

unsigned int nbytes;

void *info;

struct scatterlist *src;
struct scatterlist *dst;

void *__ctx[] CRYPTO_MINALIGN_ATTR;
};

Does someone do DMA from/to __ctx?