Re: [PATCH 00/52] [RFC] virtio-fs: shared file system for virtual machines

[Aneesh Kumar K.V]

Vivek Goyal <vgoyal@xxxxxxxxxx> writes:

> Hi,
>
> Here are RFC patches for virtio-fs. Looking for feedback on this approach.
>
> These patches should apply on top of 4.20-rc5. We have also put code for
> various components here.
>
> https://gitlab.com/virtio-fs
>
> Problem Description
> ===================
> We want to be able to take a directory tree on the host and share it with
> guest[s]. Our goal is to be able to do it in a fast, consistent and secure
> manner. Our primary use case is kata containers, but it should be usable in
> other scenarios as well.
>
> Containers may rely on local file system semantics for shared volumes,
> read-write mounts that multiple containers access simultaneously.  File
> system changes must be visible to other containers with the same consistency
> expected of a local file system, including mmap MAP_SHARED.
>
> Existing Solutions
> ==================
> We looked at existing solutions and virtio-9p already provides basic shared
> file system functionality although does not offer local file system semantics,
> causing some workloads and test suites to fail.

Can you elaborate on this? Is this with 9p2000.L ? We did quiet a lot of
work to make sure posix test suite pass on 9p file system. Also 
was the mount option with cache=loose?

-aneesh