[PATCH v4 7/7] KVM: arm: enable KVM_SIGNAL_MSI and MSI routing

Eric Auger
2016-04-04T08:48:02Z

If the ITS modality is not available, let's simply support MSI
injection by transforming the MSI.data into an SPI ID.

This becomes possible to use KVM_SIGNAL_MSI ioctl and MSI
routing for arm too.

Signed-off-by: Eric Auger <eric.auger@linaro.org>

---

v2 -> v3:
- reword the commit message
- add sanity check about devid provision

v1 -> v2:
- introduce vgic_v2m_inject_msi in vgic-v2-emul.c following Andre's
advice

Conflicts:
arch/arm/kvm/Kconfig

Conflicts:
arch/arm/kvm/Kconfig
---
arch/arm/kvm/Kconfig | 1 +
virt/kvm/arm/vgic/vgic-v2.c | 15 +++++++++++++++
virt/kvm/arm/vgic/vgic.h | 1 +
virt/kvm/arm/vgic/vgic_irqfd.c | 2 +-
4 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/arch/arm/kvm/Kconfig b/arch/arm/kvm/Kconfig
index 92c3aec..67019e5 100644
--- a/arch/arm/kvm/Kconfig
+++ b/arch/arm/kvm/Kconfig
@@ -50,6 +50,7 @@ config KVM_NEW_VGIC
bool "New VGIC implementation"
depends on KVM
default y
+ select HAVE_KVM_MSI
select HAVE_KVM_IRQCHIP
select HAVE_KVM_IRQ_ROUTING
---help---
diff --git a/virt/kvm/arm/vgic/vgic-v2.c b/virt/kvm/arm/vgic/vgic-v2.c
index 5f7c289..7400af0 100644
--- a/virt/kvm/arm/vgic/vgic-v2.c
+++ b/virt/kvm/arm/vgic/vgic-v2.c
@@ -248,6 +248,21 @@ void vgic_v2_enable(struct kvm_vcpu *vcpu)
vcpu->arch.vgic_cpu.vgic_v2.vgic_hcr = GICH_HCR_EN;
}

+/**
+ * vgic_v2m_inject_msi: emulates GICv2M MSI injection by injecting
+ * the SPI ID matching the msi data
+ *
+ * @kvm: pointer to the kvm struct
+ * @msi: the msi struct handle
+ */
+int vgic_v2m_inject_msi(struct kvm *kvm, struct kvm_msi *msi)
+{
+ if (msi->flags & KVM_MSI_VALID_DEVID)
+ return -EINVAL;
+
+ return kvm_vgic_inject_irq(kvm, 0, msi->data, 1);
+}
+
int vgic_v2_map_resources(struct kvm *kvm)
{
struct vgic_dist *dist = &kvm->arch.vgic;
diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
index 223c778..354a865 100644
--- a/virt/kvm/arm/vgic/vgic.h
+++ b/virt/kvm/arm/vgic/vgic.h
@@ -44,6 +44,7 @@ int vgic_v2_probe(struct device_node *vgic_node);
int vgic_v2_map_resources(struct kvm *kvm);
int vgic_register_dist_regions(struct kvm *kvm, gpa_t dist_base_address,
enum vgic_type);
+int vgic_v2m_inject_msi(struct kvm *kvm, struct kvm_msi *msi);

#ifdef CONFIG_KVM_ARM_VGIC_V3
void vgic_v3_irq_change_affinity(struct kvm *kvm, u32 intid, u64 mpidr);
diff --git a/virt/kvm/arm/vgic/vgic_irqfd.c b/virt/kvm/arm/vgic/vgic_irqfd.c
index a3a7f02..588cdd6 100644
--- a/virt/kvm/arm/vgic/vgic_irqfd.c
+++ b/virt/kvm/arm/vgic/vgic_irqfd.c
@@ -100,7 +100,7 @@ int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
msi.devid = e->devid;

if (!vgic_has_its(kvm))
- return -ENODEV;
+ return vgic_v2m_inject_msi(kvm, &msi);

return vits_inject_msi(kvm, &msi);
}
--
1.9.1