On Mon, May 09, 2016 at 05:18:42PM +0100, Daniel P. Berrange wrote:
On Mon, May 09, 2016 at 04:57:17PM +0100, Stefan Hajnoczi wrote:
> virtio-vsock support has been added to the nfs-ganesha NFS server. I'm
> currently working on upstreaming virtio-vsock into Linux and QEMU. I
> also have patches for the Linux NFS client and server.
>
> Users wishing to share a file system with the guest will need to
> configure the NFS server. Perhaps libvirt could handle that given that
> it already has <filesystem> syntax.
>
> The basic task is setting up either the kernel nfsd or nfs-ganesha for
> the VM to access the NFS export(s). When the VM is destroy the NFS
> server can be shut down.
Can you elaborate on the interaction between QEMU and the NFS server
on the host ? What actually needed changing in nfs-ganesha to support
virtio-vsock ? I thought that on the host side we wouldn't need any
changes, because QEMU would just talk to a regular NFS server over
TCP, and the only virtio-vsock changes would be in QEMU and the guest
kernel.
The NFS protocol (and SUNRPC) is aware of the transport its running
over. In order to fully support the protocol it needs to know about
AF_VSOCK and addressing.
The NFS server changes allow specifying an AF_VSOCK listen port. The
machine name format in /etc/exports or equivalent config also needs to
support vsock.
Stefan