[libvirt] Intend to add fuse filesystem support for libvirt lxc

[Gao feng]

Hi Everyone,

Now I'm working on making the container's system info(such as /proc/meminfo,cpuinfo..) isolate from
the host.

I made a patch which implement showing the /proc/meminfo base on container's memcg,
and sent it to the community.(http://marc.info/?l=linux-mm&m=133826035821338&w=2)

but I found it's difficult to be accepted, because this way is ugly,
and somebody gave me some suggestions.

the first way is making another kernel file(just like memory.limit_in_bytes),and mount it to the container.
I don't like this way,because there will be many redundance information between this new kernel file and
the existing kernel file,some files such as memory.stat already contains memcg information.

the other way is adding fuse filesystem support for libvirt lxc.
with this way,
we can simply collect information from cgroup in fuse_operations.read function,
and mount this file to the container.
we can impletment isolate meminfo in userspace without changing kernel codes.

I have impletment fuse support for libvrit now, and ready to impletement the meminfo isolated.

I want to know if you have any comment or another ideas?

please let me know.

thanks.