Question about ION carveout heap support partial cache flush

[Russell King - ARM Linux]

On Mon, Aug 27, 2012 at 04:23:31PM +0800, zhangfei gao wrote:
> On Mon, Aug 27, 2012 at 1:46 PM, Haojian Zhuang
> <haojian.zhuang at gmail.com> wrote:
> > Let me summerize it. First, user space address is mapped. Then,
> > flushing user space
> > address is triggered. It's a workaround of fixing non-existed virtual
> > address without fixing
> > vmap() or any other solution. It's just a quick fix.
> >
> > Zhangfei,
> > I doubt that the issue may be caused by missing memory barrier.
> > Flushing is using
> > coprocessor instructions. It's a little different.
> 
> Is there any limitation that dmac_map_area & dmac_flush_range
> supporting addr mapped from user space?

They DEFINITELY DO NOT SUPPORT FLUSHING USER SPACE.