[Qemu-devel] Re: [PATCH v5 4/5] Inter-VM shared memory PCI device

[Cam Macdonell <cam@cs.ualberta.ca>]

On Mon, May 10, 2010 at 10:52 AM, Anthony Liguori <anthony@codemonkey.ws> wrote:
>> Yes, I think the ack is the way to go, so the guest has to be aware of
>> it.  Would setting a flag in the driver-specific config space be an
>> acceptable ack that the shared region is now mapped?
>>
>
> You know it's mapped because it's mapped when the pci map function returns.
>  You don't need the guest to explicitly tell you.
>

I've been playing with migration.  It appears that the memory is
preserved on migration in the default case which makes sense as it is
part of the qemu memory allocation.  In my current implementation, I
"map" the shared memory in by calling cpu_register_physical_memory()
with the offset returned from qemu_ram_map().

My question is how to I unregister the physical memory so it is not
copied on migration (for the role=peer case).  There isn't a
cpu_unregister_physical_memory().

Cam