virgl: support PIPE_CAP_BUFFER_MAP_PERSISTENT_COHERENT
We should have GL4.5 with this. Piglit tests should now pass.
In terms of performance, we're between 70% to 80% of host
performance on Iris, based on a apitrace of a 2013 GL4.5
game:
11.204 FPS (guest)
15.947 FPS (host)
This is still better than the status quo, when said game was unplayable
with Virgl due to an inefficient GL4.3 fallback.
TEST=piglit -t arb_buffer_storage all results/ passes
Reviewed-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4821>
3 files changed
