Re: [PATCH] sparc: use asm-generic/scatterlist.h

From: FUJITA Tomonori
Date: Mon Mar 01 2010 - 01:05:57 EST

On Fri, 26 Feb 2010 04:35:36 -0800 (PST)
David Miller <davem@xxxxxxxxxxxxx> wrote:

> From: FUJITA Tomonori <fujita.tomonori@xxxxxxxxxxxxx>
> Date: Fri, 26 Feb 2010 09:43:51 +0900
> > sparc's scatterlist structure is identical to the generic one.
> >
> > Signed-off-by: FUJITA Tomonori <fujita.tomonori@xxxxxxxxxxxxx>
> Applied, thank you.


> BTW, the conditional sg_dma_len() definition cpp games done
> in asm-generic/scatterlist.h might be superfluous these days.

You are referring to the following code (I guess that this hack came
from x86)?

#if __BITS_PER_LONG == 64
#define sg_dma_len(sg) ((sg)->dma_length)
#define sg_dma_len(sg) ((sg)->length)
#endif /* 64 bit */

if so, seems that you are right. we could simply have:

#define sg_dma_len(sg) ((sg)->dma_length)

The current users of asm-generic/scatterlist.h are microblaze, s390,
score, sh, and x86.

The first three users don't support DMA so sg_dma_len doesn't matter
for them.

sh and x86_32 use sg->length, x86_64 uses sg->dma_length. However, sh
and x86_32 sets dma_length in dma_map_sg() so they can use

I'll clean up this in the next merge window.
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