Messages in this thread | | | Subject | Re: AGP & non-root mmap calls: "lending" priviledges to a client | Date | Sun, 18 Jul 1999 13:05:34 +0100 (BST) | From | Alan Cox <> |
| |
> A question that has been presented to us is that of direct mmap() access to > AGP bridge-viewed RAM. For our AGP/GART device, the client non-root > processes that are coordinated by the X server are handed a "magic cookie" > that can be used to "bless" a device file descriptor (allowed inside the > kernel) ... and thus allow any mmap as needed directly from the AGP/GART > device. In general, then, only smart and X-server coordinated processes are > then able to do this, enhancing stability, but decreasing unneeded > centralization. > > Are there any plans to allow "handing over" priviledges to clients, from one > process to another? Should a technique of "trusted-cookies" be used to
It already exists for general handle passing for file handles. Precision Insight have a fairly clean working kernel module (free software) in progress for doing the direct render resource management 'right' in a similar style to SGI.
Alan
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/
| |