convert to use generic dma_map_ops struct, cleanup

Ingo Molnar <mingo@elte.hu> wrote:

> looks good on x86 but on ia64 there's a problem with one of the
> prototypes:
>
> In file included from tip/arch/ia64/include/asm/io.h:72,
>                  from tip/arch/ia64/include/asm/smp.h:20,
>                  from tip/include/linux/smp.h:33,
>                  from tip/include/linux/sched.h:68,
>                  from tip/arch/ia64/kernel/asm-offsets.c:9:
> tip/arch/ia64/include/asm/machvec.h:101: warning: parameter has incomplete type
> tip/arch/ia64/include/asm/machvec.h:103: warning: parameter has incomplete type
>
> that's about "enum dma_data_direction".
>
> I dont think enums can be forward declared like that.
>
> machvec.h is a fairly lowlevel include file - so including
> linux/dma-mapping.h probably wont work. We could do a
> linux/dma-mapping-types.h file that is more lowlevel, or we could move the
> machvec_dma_sync_single() and machvec_dma_sync_sg() declarations to a more
> highlevel file - like arch/ia64/include/asm/dma-mapping.h.
>
> To me the latter looks cleaner but no strong feelings.

Yeah, agreed.

They are generic IA64 DMA operations so I think that it makes sense to
move them to dma-mapping.h.

Signed-off-by: Ingo Molnar <mingo@elte.hu>