Re: [RFC PATCH v1 00/15] Xen PV backend support for KVM/Xen guests

[Joao Martins]

On 10/01/2023 15:43, Joao Martins wrote:
> On 10/01/2023 12:37, David Woodhouse wrote:
>> So for now we'll limit the
>> back ends to mapping a single grant ref at a time.
>>
> Which is not a practical limitation right now. 

Gah, no. xen-usb and 9p do use possibly-discontiguous grant maps :(

> One grant ref is actually fine
> for the everything else that is not the block shared-ring.  Xen devices in 
> Qemu
> seem to be using the legacy backend interface, and thus (un)mapping one grant 
> at
> a time, or otherwise copying grefs.
>