[PATCH RFC 09/39] KVM: x86: declare Xen HVM guest capability

From: Joao Martins
Date: Wed Feb 20 2019 - 15:17:43 EST


Also take the chance to document this rather old capability of
KVM_CAP_XEN_HVM which only means it supports the Xen hypercall MSR.

Signed-off-by: Joao Martins <joao.m.martins@xxxxxxxxxx>
---
Documentation/virtual/kvm/api.txt | 14 ++++++++++++++
arch/x86/kvm/x86.c | 1 +
include/uapi/linux/kvm.h | 3 +++
3 files changed, 18 insertions(+)

diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index 356156f5c52d..c3a1402b76bf 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -5016,6 +5016,7 @@ CPU when the exception is taken. If this virtual SError is taken to EL1 using
AArch64, this value will be reported in the ISS field of ESR_ELx.

See KVM_CAP_VCPU_EVENTS for more details.
+
8.20 KVM_CAP_HYPERV_SEND_IPI

Architectures: x86
@@ -5023,3 +5024,16 @@ Architectures: x86
This capability indicates that KVM supports paravirtualized Hyper-V IPI send
hypercalls:
HvCallSendSyntheticClusterIpi, HvCallSendSyntheticClusterIpiEx.
+
+8.21 KVM_CAP_XEN_HVM
+
+Architectures: x86
+
+This capability indicates that KVM supports the Xen hypercall page MSR.
+
+8.22 KVM_CAP_XEN_HVM_GUEST
+
+Architectures: x86
+
+This capability indicates that KVM supports Xen HVM guests.
+This includes KVM_IRQ_ROUTING_XEN_EVTCHN as well.
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 888598fdf543..11b9ff2bd901 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3009,6 +3009,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
case KVM_CAP_PIT_STATE2:
case KVM_CAP_SET_IDENTITY_MAP_ADDR:
case KVM_CAP_XEN_HVM:
+ case KVM_CAP_XEN_HVM_GUEST:
case KVM_CAP_VCPU_EVENTS:
case KVM_CAP_HYPERV:
case KVM_CAP_HYPERV_VAPIC:
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index b91e57d9e6d3..682ea00abd58 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -1003,6 +1003,7 @@ struct kvm_ppc_resize_hpt {
#define KVM_CAP_ARM_VM_IPA_SIZE 165
#define KVM_CAP_MANUAL_DIRTY_LOG_PROTECT 166
#define KVM_CAP_HYPERV_CPUID 167
+#define KVM_CAP_XEN_HVM_GUEST 168

#ifdef KVM_CAP_IRQ_ROUTING

@@ -1455,6 +1456,7 @@ struct kvm_enc_region {
/* Available with KVM_CAP_HYPERV_CPUID */
#define KVM_GET_SUPPORTED_HV_CPUID _IOWR(KVMIO, 0xc1, struct kvm_cpuid2)

+/* Available with KVM_CAP_XEN_HVM_GUEST */
#define KVM_XEN_HVM_GET_ATTR _IOWR(KVMIO, 0xc2, struct kvm_xen_hvm_attr)
#define KVM_XEN_HVM_SET_ATTR _IOW(KVMIO, 0xc3, struct kvm_xen_hvm_attr)

@@ -1472,6 +1474,7 @@ struct kvm_xen_hvm_attr {
} u;
};

+/* Available with KVM_CAP_XEN_HVM_GUEST */
#define KVM_XEN_ATTR_TYPE_SHARED_INFO 0x0
#define KVM_XEN_ATTR_TYPE_VCPU_INFO 0x1
#define KVM_XEN_ATTR_TYPE_VCPU_TIME_INFO 0x2
--
2.11.0