[Virtio-fs] [PATCH] virtiofs: Export filesystem tags through sysfs

[Miklos Szeredi]

On Thu, 5 Oct 2023 at 22:30, Vivek Goyal <vgoyal at redhat.com> wrote:
>
> virtiofs filesystem is mounted using a "tag" which is exported by the
> virtiofs device. virtiofs driver knows about all the available tags but
> these are not exported to user space.
>
> People have asked these tags to be exported to user space. Most recently
> Lennart Poettering has asked for it as he wants to scan the tags and mount
> virtiofs automatically in certain cases.
>
> https://gitlab.com/virtio-fs/virtiofsd/-/issues/128
>
> This patch exports tags through sysfs. One tag is associated with each
> virtiofs device. A new "tag" file appears under virtiofs device dir.
> Actual filesystem tag can be obtained by reading this "tag" file.
>
> For example, if a virtiofs device exports tag "myfs", a new file "tag"
> will show up here.
>
> /sys/bus/virtio/devices/virtio<N>/tag
>
> # cat /sys/bus/virtio/devices/virtio<N>/tag
> myfs
>
> Signed-off-by: Vivek Goyal <vgoyal at redhat.com>

Hi Vivek,

This needs something under Documentation/.

While the interface looks good to me, I think we need an ack on that
from the virtio maintainer.

Thanks,
Miklos