How to bypass cache from driver?

Hello all,
I’m new in using TX2. I’ve traced the driver source code, nvmap, for few weeks.
As I figure out, nvmap is close to the communication between cpu and gpu instead of only gpu.
Then I trace another source code, nvgpu, but I cannot understand the code. I wonder if there are some guide to lead me to know more about it??
As the topic, I also want to know how to bypass the L1 or L2 cache of gpu from driver instead of using PTX or CUDA.
Also, I want to know if gpu can direct access swap space from driver?

THX

hello chinessgo55,

you may refer to Accelerated GStreamer User Guide, please check [gst-nvivafilter] plug-in for directly memory access.
thanks