On Tue, Mar 20, 2012 at 09:53:05PM +0100, Daniel Vetter wrote:
Note taht this dma-buf mmap patch does _not_ support every possible insanity an existing subsystem could pull of with mmap: Because it does not allow to intercept pagefaults and shoot down ptes importing subsystems can't add some magic of their own at these points (e.g. to automatically synchronize with outstanding rendering or set up some special resources). I've done a cursory read through a few mmap implementions of various subsytems and I'm hopeful that we can avoid this (and the complexity it'd bring with it).
To clarify: This concerns the importer. The exporter is of course still free to do whatever it pleases. But the goal of this exercise is that importing subsystems can still offer an identical userspace interfaces for buffers imported through dma-buf and native ones, hence why I've mentioned it. -Daniel