On 11.09.2024 08:58, Jiqian Chen wrote:
> The current hypercall interfaces to manage and assign interrupts to
> domains is mostly based in using pIRQs as handlers. Such pIRQ values
> are abstract domain-specific references to interrupts.
>
> Classic HVM domains can have access to {,un}map_pirq hypercalls if the
> domain is allowed to route physical interrupts over event channels.
> That's however a different interface, limited to only mapping
> interrupts to itself. PVH domains on the other hand never had access
> to the interface, as PVH domains are not allowed to route interrupts
> over event channels.
>
> In order to allow setting up PCI passthrough from a PVH domain it
> needs access to the {,un}map_pirq hypercalls so interrupts can be
> assigned a pIRQ handler that can then be used by further hypercalls to
> bind the interrupt to a domain.
>
> Note that the {,un}map_pirq hypercalls end up calling helpers that are
> already used against a PVH domain in order to setup interrupts for the
> hardware domain when running in PVH mode. physdev_map_pirq() will
> call allocate_and_map_{gsi,msi}_pirq() which is already used by the
> vIO-APIC or the vPCI code respectively. So the exposed code paths are
> not new when targeting a PVH domain, but rather previous callers are
> not hypercall but emulation based.
>
> Signed-off-by: Jiqian Chen <jiqian.c...@amd.com>
> Signed-off-by: Huang Rui <ray.hu...@amd.com>
> Signed-off-by: Jiqian Chen <jiqian.c...@amd.com>
Acked-by: Jan Beulich <jbeul...@suse.com>
