On Sat, Nov 11, 2023 at 06:55:18AM -0500, Greg KH wrote: > On Wed, Nov 08, 2023 at 04:33:33PM -0500, Vivek Goyal 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. Tag has a newline char at the end. > > > > /sys/bus/virtio/devices/virtio<N>/tag > > > > # cat /sys/bus/virtio/devices/virtio<N>/tag > > myfs > > > > Note, tag is available at KOBJ_BIND time and not at KOBJ_ADD event time. > > > > v2: > > - Add a newline char at the end in tag file. (Alyssa Ross) > > - Add a line in commit logs about tag file being available at KOBJ_BIND > > time and not KOBJ_ADD time. > > > > Signed-off-by: Vivek Goyal <vgoyal@xxxxxxxxxx> > > Reviewed-by: Stefan Hajnoczi <stefanha@xxxxxxxxxx> > > --- > > fs/fuse/virtio_fs.c | 34 ++++++++++++++++++++++++++++++++++ > > 1 file changed, 34 insertions(+) > > No documentation for your new sysfs file? :( Hi Greg, My bad. I forgot about it while posting V2. As per your comment in another email, I will include some documentation in Documentation/ABI/. Not very sure what file name to choose. I will probably start with "sysfs-bus-virtio-devices-virtiofs". Thanks Vivek
