Question about ION carveout heap support partial cache flush

On Mon, Aug 27, 2012 at 04:23:31PM +0800, zhangfei gao wrote:

On Mon, Aug 27, 2012 at 1:46 PM, Haojian Zhuang
[off-list ref] wrote:

quoted

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.