On 26/08/17 20:49, Christoffer Dall wrote:

On Mon, Jul 31, 2017 at 06:26:17PM +0100, Marc Zyngier wrote:

quoted

Add a new has_gicv4 field in the global VGIC state that indicates
whether the HW is GICv4 capable, as a per-VM predicate indicating
if there is a possibility for a VM to support direct injection
(the above being true and the VM having an ITS).

Signed-off-by: Marc Zyngier <redacted>
---
 include/kvm/arm_vgic.h           | 3 +++
 virt/kvm/arm/vgic/vgic-mmio-v3.c | 5 +++++
 virt/kvm/arm/vgic/vgic.h         | 2 ++
 3 files changed, 10 insertions(+)

diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index ee8587c8c715..84694b42373a 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h

@@ -73,6 +73,9 @@ struct vgic_global {
 	/* Only needed for the legacy KVM_CREATE_IRQCHIP */
 	bool			can_emulate_gicv2;
 
+	/* Does have GICv4? */

nit: questionable comment, how about

  /* Hardware has GICv4? */
or
  /* Do we have GICv4? */

Yup, reads much better.

quoted

+	bool			has_gicv4;
+
 	/* GIC system register CPU interface */
 	struct static_key_false gicv3_cpuif;
 

diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c
index 714fa3933546..74109ca75cc0 100644
--- a/virt/kvm/arm/vgic/vgic-mmio-v3.c
+++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c

@@ -54,6 +54,11 @@ bool vgic_has_its(struct kvm *kvm)
 	return dist->has_its;
 }
 
+bool vgic_is_v4_capable(struct kvm *kvm)
+{
+	return kvm_vgic_global_state.has_gicv4 && vgic_has_its(kvm);
+}
+

uber nit: the naming here is a bit funny, because we won't be presenting
a GICv4 GIC to the guest, so I'd prefer something like
vgic_supports_direct_msis() or something like that, but this is
obviously not a deal breaker.

I like it. It has the advantage of not tying the predicate to a
particular direct injection method, should we one day have a GICv6 (no,
please...).

Thanks,

	M.
-- 
Jazz is not dead. It just smells funny...