Re: [GIT PATCH] Fix asm-avr32/dma-mapping.h breakage

Adrian Bunk
2007-10-24T12:41:05Z

On Wed, Oct 24, 2007 at 02:21:20PM +0200, Jens Axboe wrote:
> On Wed, Oct 24 2007, Robert P. J. Day wrote:
> > On Wed, 24 Oct 2007, Sam Ravnborg wrote:
> >
> > > On Wed, Oct 24, 2007 at 01:24:53PM +0200, Jens Axboe wrote:
> > > > On Wed, Oct 24 2007, Haavard Skinnemoen wrote:
> > > > > Hi Linus,
> > > > >
> > > > > Sorry about sending you pull requests so rapidly, but Jens broke my
> > > > > dma-mapping.h yesterday. Or you may say the bug was there to begin with
> > > > > and Jens merely exposed it, but that makes it sound like my fault ;-)
> > > > >
> > > > > Anyway, please pull from
> > > > >
> > > > > ssh://master.kernel.org/pub/scm/linux/kernel/git/hskinnemoen/avr32-2.6.git for-linus
> > > > >
> > > > > to receive the following update.
> > > >
> > > > You should not take the blame :-)
> > > >
> > > > I'm collecting these patches, so I'll pull your fix and make sure it
> > > > gets to Linus today along with the other fixes.
> > >
> > > How about doing a "git grep asm/scatterlist"
> > > and fix all victims to use linux/scatterlist?
> > > Or you maybe did this already.
> >
> > i was just about to ask -- is this one of those cases where the asm
> > versions of scatterlist.h should have a warning/error that they should
> > not be included directly, and to include linux/scatterlist.h instead?
>
> No, using asm/scatterlist.h is perfectly fine. The problem is code using
> the sg helpers should include linux/scatterlist.h since that is where
> those are defined.
>
> If you just need the scatterlist structure definition, then
> asm/scatterlist.h is the correct include.

But there's also the general question whether it's good practice for
not architecture specific code to include asm/ headers.

For APIs available on all architectures linux/ header are the right
thing to use, and what is in the asm/ header and what in the linux/
header becomes an implementation detail that can be changed.

> Jens Axboe

cu
Adrian

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