Clean/Invalidate L1/L2 DCache on userspace.

[Richard Liu]

Hi All:

     Does any one try to clean/invalidate L2 Dcache for userspace memory?

Program allocated a memory from malloc on userspace.
Tried to pass userspace memory point to kernel and use function 
"dma_cache_maint" to flush/invalidate it.
But it's not work.

     sys_cacheflush seems only flush L1 and icache only.
It doesn't fit my requirement.
So, I cannot find any solution to clean/invalidate L2 Dcache from user 
space.