On Mon, Feb 12, 2024 at 07:11:46PM -0500, Stefan Hajnoczi wrote: > v4: > - Create kset before registering virtio driver because the kset needed in > virtio_fs_probe(). Solves the empty /sys/fs/virtiofs bug. [Vivek] > v3: > - Use dev_dbg() to avoid spamming logs [Greg] > - Fix 644 mode on "tag" attr and use __ATTR_RO() [Greg] > - Use kset_uevent_ops and eliminate explicit KOBJ_REMOVE [Greg] > v2: > - Vivek mentioned that he didn't have time to work on this patch series > recently so I gave it a shot. > - Information is now exposed in /sys/fs/virtiofs/ whereas before it was part of > the generic virtio device kobject, which didn't really fit. > > Userspace needs a way to enumerate available virtiofs filesystems and detect > when they are hotplugged or unplugged. This would allow systemd to wait for a > virtiofs filesystem during boot, for example. > > This patch series adds the following in sysfs: > > /sys/fs/virtiofs/<n>/tag - unique identifier for mount(8) > /sys/fs/virtiofs/<n>/device - symlink to virtio device > > A uevent is emitted when virtiofs devices are hotplugged or unplugged: > > KERNEL[111.113221] add /fs/virtiofs/2 (virtiofs) > ACTION=add > DEVPATH=/fs/virtiofs/2 > SUBSYSTEM=virtiofs > TAG=test > > KERNEL[165.527167] remove /fs/virtiofs/2 (virtiofs) > ACTION=remove > DEVPATH=/fs/virtiofs/2 > SUBSYSTEM=virtiofs > TAG=test > > Stefan Hajnoczi (3): > virtiofs: forbid newlines in tags > virtiofs: export filesystem tags through sysfs > virtiofs: emit uevents on filesystem events Hi Stefan, Thanks a lot for this patch series. It looks good to me. I also tested and now I can see entries in /sys/fs/virtiofs/. I also wrote a udev rule and a mount unit file to automatically mount virtiofs instance and unmount when device is unplugged. Everything seems to work. Hence.. Reviewed-by: Vivek Goyal <vgoyal@xxxxxxxxxx> Thanks Vivek > > fs/fuse/virtio_fs.c | 137 ++++++++++++++++---- > Documentation/ABI/testing/sysfs-fs-virtiofs | 11 ++ > 2 files changed, 126 insertions(+), 22 deletions(-) > create mode 100644 Documentation/ABI/testing/sysfs-fs-virtiofs > > -- > 2.43.0 >
