On 07.12.24 11:50, Julia Zhang wrote:
To implement dGPU prime feature, virtgpu needs to import/export buffer between virtio iGPU and passthrough dGPU. Before that, virtgpu should check if P2P is possible or not. But calling function pci_p2pdma_distance in guest VM will only get virtual p2pdma_distance instead of real physical p2pdma_distance.So this series introduce an implementation of virtgpu device_attachcallback to get p2pdma_distance. And also adds a new virtgpu command to pass PCI notations from guest to host and a new xen privcmd to get physical p2pdma_distance according to the PCI notations in host.
It is hard to review this series without having a clear picture how this all is coming together. I guess the virtgpu frontend will send a p2pdma_distance request to the backend, which is running in user mode of dom0. This backend will then call into the privcmd driver to obtain the needed information and sends it back to the frontend. Can you please confirm my suspicion is correct? Juergen
OpenPGP_0xB0DE9DD628BF132F.asc
Description: OpenPGP public key
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