Re: [Qemu-devel] Re: Add target memory mapping API

[Avi Kivity]

Mike Day wrote:
> > What is the motivation for efficient rmw?
> >     
>
> rmw would be good for changing bytes in a device config space, or
> programming an IOMMU. Right now these are not on the critical path but
> they may be soon in some cases. For example imagine an assigned I/O
> device that wants to dynamically map io translations for each DMA.
>   

You don't do these with dma, instead you use cpu instructions which go 
through cpu_physical_memory_rw().

--
error compiling committee.c: too many arguments to function