videopool: allocate page-aligned buffers
Submitted by Gwenole Beauchesne @gb
Link to original bug (#733952)
Description
In order to improve interop with GPU resources, it would help to make sure video buffer allocations are page-aligned. This is in view to using userptr (kernel >= 3.16) and expose that to the GPU for further processing.
There are two ways to implement that:
- At the video pool level, in the alloc_buffer() implementation.
- At the system allocator level, through an additional settable param.
Approach (1) is trivial, while approach (2) is more generic and has the potential to be used in other scenarios beyond video buffers.
What is the preferred approach? Thanks.