Re: documentation on using 9pfs in xen

[Paul Leiber <paul@xxxxxxxxxxxxxxxx>]

Am 20.01.2024 um 01:19 schrieb Sam Mulvey:
> Hello!
>
> I'm seeing a lot of documentation online about the *development* of 9pfs 
> in Xen going back quite a while.  I'm not finding any documentation 
> about using 9pfs in xen.  Is there anyone using it out there?   I'm 
> using PVH domUs.
This message didn't let me go. I was also interested in learning how to 
use 9pfs, and I also didn't find documentation. While procrastinating, I 
found out how to use 9pfs in Xen.
In the guest config, you need to enter a line like this (see [1]):

p9      = ['tag=test,security_model=none,path=/tmp/mnt']

In the DomU, you need to mount the file system with a mount command (see 
[2]):
mount -t 9p test /tmp/mnt/

The path for the directory to be mounted in Dom0 and the mount point in 
DomU don't need to be the same, of course. Then, you can find the 
content of the directory in Dom0 in the mount point in Dom0 and vice versa.
I didn't test this very thoroughly, but it seems be working. I hope this 
helps others.
Best regards,

Paul


[1] https://xenbits.xen.org/docs/unstable/man/xl.cfg.5.html
[2] https://wiki.qemu.org/Documentation/9psetup