Re: [Qemu-devel] [GSoC 2010] Pass-through filesystem support.

[jvrao <jvrao@linux.vnet.ibm.com>]

Mohammed Gamal wrote:
> On Tue, Apr 20, 2010 at 8:36 PM, jvrao <jvrao@linux.vnet.ibm.com> wrote:
> 
> ... <snip> ...
> 
>>> This'd be something interesting to do. I wonder if that would fit in
>>> the GSoC timeframe, or whether it'd be a little too short. So how long
>>> you'd estimate something like that would take?
>> I think it would take ~3PM for someone with decent VFS/NFS knowledge.
>> They key is fh-to-dentry mapping. In the loose cache mode client caches
>> this information .. but even in this mode we can't assume that it will be cached
>> forever. Need protocol amendments, client/server side changes to implement
>> this in the no-cache mode which can be used even in the loose cache mode when
>> we get a cache-miss.
>>
>> Thanks,
>> JV
> 
> I think I'd be glad to go for virtio-9p in GSoC. The roadmap is a
> little bit hazy for me at the moment but I think we can set the goals.
> I'd appreciate some pointers as to where to get more info on what to
> do and if there is any relevant documentation on that matter.

You can wet your feet by starting with the patch set 
"[Qemu-devel] [PATCH -V5 00/21] virtio-9p: paravirtual file system passthrough" on the mailing list.

Start QEMU on any latest distro like Fedora 12; choose mainline kernel for guest.

You can start QEMU with something like "-virtfs local,path=/tmp/,mount_tag=v_tmp" 
and mount it on the guest. ex:  mount -t 9p -o trans=virtio -o debug=0xFFFF v_tmp /mnt.

http://plan9.bell-labs.com/wiki/plan9/9p2010/index.html gives basic information on .L protocol.

You can start to play around.. by exporting NFS on top of VirtFS..

Thanks,
JV



> 
> Regards,
> Mohammed
> 
>