intel
Add hint for map operation
add hint for map operation
read/write hint represent the purpose of mapping operation
backend could optimize vaMapBuffer basing on these hint
As we discussed offline we also have a feature request to control access time. I.e. to have something like vaMapBuffer3 which accepts timeout option to give user control on how much time user can wait until GPU resource will be free (timeout 0 will mean non blocking call). We can't use two different functions to check it, because between check and use GPU may acquire resource. consider it as pure feature request, fine to have at least access flags for now
How does an application know if a driver supports vaMapBuffer2()? In the current implementation, invoking vaMapBuffer2(), getting error and then falling back to vaMapBuffer()? It seems to be inefficient. Shall we develop a better way, e.g., querying?
