OVFS, OpenDAL File System via Virtio

Virtio is an open standard designed to enhance I/O performance between virtual machines (VMs) and host systems in virtualized environments. VirtioFS is an extension of the Virtio standard specifically crafted for file system sharing between VMs and the host. This is particularly beneficial in scenarios where seamless access to shared files and data between VMs and the host is essential. VirtioFS has been widely adopted in virtualization technologies such as QEMU and Kata Container. Apache OpenDAL is a data access layer that allows users to easily and efficiently retrieve data from various storage services in a unified manner. In this project, our goal is to reference virtiofsd (a standard vhost-user backend, a pure Rust implementation of VirtioFS based on the local file system) and implement VirtioFS based on OpenDAL. Through this project, VMs can access numerous data services through the file system interface with the assistance of the OpenDAL service daemon deployed on the host, all without their awareness. It ensures the efficiency of file system reading and writing in VMs through VirtioFS support. This storage-system-as-a-service approach conceals the details of the distributed storage system from VMs. This ensures the security of storage services, as VMs do not need to be aware of the information, configuration and permission credentials of the accessed storage service. Additionally, it enables the utilization of a new backend storage system without reconfiguring all VMs.