Implement DRM Native Pixmap using prime buffer
This CL implements a new client native pixmap through the prime buffer. In
particular it uses a new feature of prime to map the exported graphics fd,
which conveniently can be used in the GpuMemoryBuffer for zero-copy (and
one-copy) rasterization in Chrome.
This pretty much replaces VGEM infrastructure when that's used to share buffers
in Chrome processes, so support for VGEM in Chrome is being removed as well in
this CL.
This feature requires Kernel changes in i915 and drm subsystems, and also in
userspace mini-gbm library.
BUG=581151
TEST=memory coherent (IvyBridge) and non-coherent hardware (BayTrail-T).
Review URL: https://codereview.chromium.org/1262043002
Cr-Commit-Position: refs/heads/master@{#383513}
29 files changed
