[RFC PATCH v2 22/69] KVM: x86: Add vm_type to differentiate legacy VMs from protected VMs

[isaku.yamahata@intel.com]

From: Sean Christopherson <sean.j.christopherson@intel.com>

Add a capability to effectively allow userspace to query what VM types
are supported by KVM.

Co-developed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
---
 arch/x86/include/asm/kvm-x86-ops.h    | 1 +
 arch/x86/include/asm/kvm_host.h       | 2 ++
 arch/x86/include/uapi/asm/kvm.h       | 4 ++++
 arch/x86/kvm/svm/svm.c                | 6 ++++++
 arch/x86/kvm/vmx/vmx.c                | 6 ++++++
 arch/x86/kvm/x86.c                    | 9 ++++++++-
 include/uapi/linux/kvm.h              | 2 ++
 tools/arch/x86/include/uapi/asm/kvm.h | 4 ++++
 tools/include/uapi/linux/kvm.h        | 2 ++
 9 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index e7bef91cee04..01457da0162b 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -18,6 +18,7 @@ KVM_X86_OP_NULL(hardware_unsetup)
 KVM_X86_OP_NULL(cpu_has_accelerated_tpr)
 KVM_X86_OP(has_emulated_msr)
 KVM_X86_OP(vcpu_after_set_cpuid)
+KVM_X86_OP(is_vm_type_supported)
 KVM_X86_OP(vm_init)
 KVM_X86_OP_NULL(vm_destroy)
 KVM_X86_OP(vcpu_create)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 80b943e4ab6d..301b10172cbf 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -975,6 +975,7 @@ struct kvm_x86_msr_filter {
 #define APICV_INHIBIT_REASON_X2APIC	5
 
 struct kvm_arch {
+	unsigned long vm_type;
 	unsigned long n_used_mmu_pages;
 	unsigned long n_requested_mmu_pages;
 	unsigned long n_max_mmu_pages;
@@ -1207,6 +1208,7 @@ struct kvm_x86_ops {
 	bool (*has_emulated_msr)(struct kvm *kvm, u32 index);
 	void (*vcpu_after_set_cpuid)(struct kvm_vcpu *vcpu);
 
+	bool (*is_vm_type_supported)(unsigned long vm_type);
 	unsigned int vm_size;
 	int (*vm_init)(struct kvm *kvm);
 	void (*vm_destroy)(struct kvm *kvm);
diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h
index 0662f644aad9..8341ec720b3f 100644
--- a/arch/x86/include/uapi/asm/kvm.h
+++ b/arch/x86/include/uapi/asm/kvm.h
@@ -490,4 +490,8 @@ struct kvm_pmu_event_filter {
 #define KVM_PMU_EVENT_ALLOW 0
 #define KVM_PMU_EVENT_DENY 1
 
+#define KVM_X86_LEGACY_VM	0
+#define KVM_X86_SEV_ES_VM	1
+#define KVM_X86_TDX_VM		2
+
 #endif /* _ASM_X86_KVM_H */
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 25c72925eb8a..286a49b09269 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -4422,6 +4422,11 @@ static void svm_vm_destroy(struct kvm *kvm)
 	sev_vm_destroy(kvm);
 }
 
+static bool svm_is_vm_type_supported(unsigned long type)
+{
+	return type == KVM_X86_LEGACY_VM;
+}
+
 static int svm_vm_init(struct kvm *kvm)
 {
 	if (!pause_filter_count || !pause_filter_thresh)
@@ -4448,6 +4453,7 @@ static struct kvm_x86_ops svm_x86_ops __initdata = {
 	.vcpu_free = svm_free_vcpu,
 	.vcpu_reset = svm_vcpu_reset,
 
+	.is_vm_type_supported = svm_is_vm_type_supported,
 	.vm_size = sizeof(struct kvm_svm),
 	.vm_init = svm_vm_init,
 	.vm_destroy = svm_vm_destroy,
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 6c043a160b30..84c2df824ecc 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -6951,6 +6951,11 @@ static int vmx_create_vcpu(struct kvm_vcpu *vcpu)
 	return err;
 }
 
+static bool vmx_is_vm_type_supported(unsigned long type)
+{
+	return type == KVM_X86_LEGACY_VM;
+}
+
 #define L1TF_MSG_SMT "L1TF CPU bug present and SMT on, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details.\n"
 #define L1TF_MSG_L1D "L1TF CPU bug present and virtualization mitigation disabled, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details.\n"
 
@@ -7605,6 +7610,7 @@ static struct kvm_x86_ops vmx_x86_ops __initdata = {
 	.cpu_has_accelerated_tpr = report_flexpriority,
 	.has_emulated_msr = vmx_has_emulated_msr,
 
+	.is_vm_type_supported = vmx_is_vm_type_supported,
 	.vm_size = sizeof(struct kvm_vmx),
 	.vm_init = vmx_vm_init,
 
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 9244d1d560d5..d7110d48cbc1 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3995,6 +3995,11 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 		else
 			r = 0;
 		break;
+	case KVM_CAP_VM_TYPES:
+		r = BIT(KVM_X86_LEGACY_VM);
+		if (static_call(kvm_x86_is_vm_type_supported)(KVM_X86_TDX_VM))
+			r |= BIT(KVM_X86_TDX_VM);
+		break;
 	default:
 		break;
 	}
@@ -10746,9 +10751,11 @@ void kvm_arch_free_vm(struct kvm *kvm)
 
 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 {
-	if (type)
+	if (!static_call(kvm_x86_is_vm_type_supported)(type))
 		return -EINVAL;
 
+	kvm->arch.vm_type = type;
+
 	INIT_HLIST_HEAD(&kvm->arch.mask_notifier_list);
 	INIT_LIST_HEAD(&kvm->arch.active_mmu_pages);
 	INIT_LIST_HEAD(&kvm->arch.zapped_obsolete_pages);
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 79d9c44d1ad7..52b3e212037a 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -1084,6 +1084,8 @@ struct kvm_ppc_resize_hpt {
 #define KVM_CAP_VM_COPY_ENC_CONTEXT_FROM 197
 #define KVM_CAP_PTP_KVM 198
 
+#define KVM_CAP_VM_TYPES 1000
+
 #ifdef KVM_CAP_IRQ_ROUTING
 
 struct kvm_irq_routing_irqchip {
diff --git a/tools/arch/x86/include/uapi/asm/kvm.h b/tools/arch/x86/include/uapi/asm/kvm.h
index 0662f644aad9..8341ec720b3f 100644
--- a/tools/arch/x86/include/uapi/asm/kvm.h
+++ b/tools/arch/x86/include/uapi/asm/kvm.h
@@ -490,4 +490,8 @@ struct kvm_pmu_event_filter {
 #define KVM_PMU_EVENT_ALLOW 0
 #define KVM_PMU_EVENT_DENY 1
 
+#define KVM_X86_LEGACY_VM	0
+#define KVM_X86_SEV_ES_VM	1
+#define KVM_X86_TDX_VM		2
+
 #endif /* _ASM_X86_KVM_H */
diff --git a/tools/include/uapi/linux/kvm.h b/tools/include/uapi/linux/kvm.h
index 79d9c44d1ad7..52b3e212037a 100644
--- a/tools/include/uapi/linux/kvm.h
+++ b/tools/include/uapi/linux/kvm.h
@@ -1084,6 +1084,8 @@ struct kvm_ppc_resize_hpt {
 #define KVM_CAP_VM_COPY_ENC_CONTEXT_FROM 197
 #define KVM_CAP_PTP_KVM 198
 
+#define KVM_CAP_VM_TYPES 1000
+
 #ifdef KVM_CAP_IRQ_ROUTING
 
 struct kvm_irq_routing_irqchip {
-- 
2.25.1