On Wed, Apr 20, 2011 at 8:25 AM, Arnd Bergmann arnd@arndb.de wrote:
On Wednesday 20 April 2011 03:52:53 Clark, Rob wrote:
From DRI perspective.. I guess the global buffer name is restricted to a 4 byte integer, unless you change the DRI proto..
I still like the idea of using file handles to pass the buffers between kernel subsystems. Maybe there could be an ioctl to encapsulate a buffer from DRI in a file so we can give it to another subsystem, and/or an ioctl to register a buffer from a file handle with DRI.
That's been the original design of gem, i.e. using fd handles (and perhaps even passing them around in unix domain sockets). There's one small problem with that approach: You're quickly running out of fds with the linux default limit of 1024. Hence the roll-your-own approach.
Aside: I'll be participating as a gem drm/i915 hacker. I'll send a short overview of how gem/kms tackles these problems after easter because our approach is rather different from what the arm community seems to want (as far as I can tell). -Daniel