[RFC PATCH v5 010/104] KVM: TDX: Make TDX VM type supported

[isaku . yamahata]

From: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>

As first step TDX VM support, return that TDX VM type supported to device
model, e.g. qemu.  The callback to create guest TD is vm_init callback for
KVM_CREATE_VM.  Add a place holder function and call a function to
initialize TDX module on demand because in that callback VMX is enabled by
hardware_enable callback (vmx_hardware_enable).

Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
---
 arch/x86/kvm/vmx/main.c    | 24 ++++++++++++++++++++++--
 arch/x86/kvm/vmx/tdx.c     |  5 +++++
 arch/x86/kvm/vmx/vmx.c     |  5 -----
 arch/x86/kvm/vmx/x86_ops.h |  3 ++-
 4 files changed, 29 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index 77da926ee505..8103d1c32cc9 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -5,6 +5,12 @@
 #include "vmx.h"
 #include "nested.h"
 #include "pmu.h"
+#include "tdx.h"
+
+static bool vt_is_vm_type_supported(unsigned long type)
+{
+	return type == KVM_X86_DEFAULT_VM || tdx_is_vm_type_supported(type);
+}
 
 static __init int vt_hardware_setup(void)
 {
@@ -19,6 +25,20 @@ static __init int vt_hardware_setup(void)
 	return 0;
 }
 
+static int vt_vm_init(struct kvm *kvm)
+{
+	int ret;
+
+	if (is_td(kvm)) {
+		ret = tdx_module_setup();
+		if (ret)
+			return ret;
+		return -EOPNOTSUPP;	/* Not ready to create guest TD yet. */
+	}
+
+	return vmx_vm_init(kvm);
+}
+
 struct kvm_x86_ops vt_x86_ops __initdata = {
 	.name = "kvm_intel",
 
@@ -29,9 +49,9 @@ struct kvm_x86_ops vt_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,
+	.is_vm_type_supported = vt_is_vm_type_supported,
 	.vm_size = sizeof(struct kvm_vmx),
-	.vm_init = vmx_vm_init,
+	.vm_init = vt_vm_init,
 
 	.vcpu_create = vmx_vcpu_create,
 	.vcpu_free = vmx_vcpu_free,
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index 8adc87ad1807..e8d293a3c11c 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -105,6 +105,11 @@ int tdx_module_setup(void)
 	return ret;
 }
 
+bool tdx_is_vm_type_supported(unsigned long type)
+{
+	return type == KVM_X86_TDX_VM && READ_ONCE(enable_tdx);
+}
+
 static int __init __tdx_hardware_setup(struct kvm_x86_ops *x86_ops)
 {
 	u32 max_pa;
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 3c7b3f245fee..7838cd177f0e 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7079,11 +7079,6 @@ int vmx_vcpu_create(struct kvm_vcpu *vcpu)
 	return err;
 }
 
-bool vmx_is_vm_type_supported(unsigned long type)
-{
-	return type == KVM_X86_DEFAULT_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"
 
diff --git a/arch/x86/kvm/vmx/x86_ops.h b/arch/x86/kvm/vmx/x86_ops.h
index f7327bc73be0..78331dbc29f7 100644
--- a/arch/x86/kvm/vmx/x86_ops.h
+++ b/arch/x86/kvm/vmx/x86_ops.h
@@ -25,7 +25,6 @@ void vmx_hardware_unsetup(void);
 int vmx_hardware_enable(void);
 void vmx_hardware_disable(void);
 bool report_flexpriority(void);
-bool vmx_is_vm_type_supported(unsigned long type);
 int vmx_vm_init(struct kvm *kvm);
 int vmx_vcpu_create(struct kvm_vcpu *vcpu);
 int vmx_vcpu_pre_run(struct kvm_vcpu *vcpu);
@@ -130,10 +129,12 @@ void vmx_setup_mce(struct kvm_vcpu *vcpu);
 #ifdef CONFIG_INTEL_TDX_HOST
 void __init tdx_pre_kvm_init(unsigned int *vcpu_size,
 			unsigned int *vcpu_align, unsigned int *vm_size);
+bool tdx_is_vm_type_supported(unsigned long type);
 void __init tdx_hardware_setup(struct kvm_x86_ops *x86_ops);
 #else
 static inline void tdx_pre_kvm_init(
 	unsigned int *vcpu_size, unsigned int *vcpu_align, unsigned int *vm_size) {}
+static inline bool tdx_is_vm_type_supported(unsigned long type) { return false; }
 static inline void tdx_hardware_setup(struct kvm_x86_ops *x86_ops) {}
 #endif
 
-- 
2.25.1