Re: Using VMChannel to communicate with the host.

Dor Laor
2007-09-09T09:56:21Z

Cam Macdonell wrote:
> Hi,
>
> I'm trying to get a better understanding of VM-to-host communication
> that doesn't involve going over virtual networks. I understand there
> are a couple of developments underway, but I just want to play around a
> better sense of things. I think the current hypercall mechanism is the
> current way to do this using the -vmchannel option. But, I'm not very
> experienced with PCI devices and their drivers so I need some help. All
> I want to do is to communicate across a unix domain socket on the host.
> Besides loading the hypercall module in the guest how do things needs
> to be configured on the host?
>
> Is there a simple tutorial or just a webpage with examples for how to do
> this?
>
> Thanks,
> Cam
>
I just tested it, it got a little deprecated over time since it call
pci_module_init instead of pci_register_* and some more irq function
deprecation.The sysfs interface in not complete and you can't read/write
from the device.
The qemu parameters are -vmchannel di:2258,unix:/tmp/file,server
2258 is the vendor id for the device, you can use unix sockets ot even
tcp for the host end.

In several week we'll publish better version of it. Maybe we'll publish
a preview before.
-Dor