virtio-fs feature allows to share a file system between hypervisor and guest. It has been recently released for RHEL8.2:
- https://bugzilla.redhat.com/show_bug.cgi?id=1694164
In the context of CephFS and Manila, virtio-fs would allow to run the ceph client in the hypervisor to provide isolation between storage backend and tenant and later share the fs to the guest through qemu.
There was a previous RFE (for virtio-vsock) that got closed once virtio-fs was released, however the piece of code for Manila does not seem to be covered by the current code:
- https://bugzilla.redhat.com/show_bug.cgi?id=1363787