[PATCH v3 16/16] KVM: TDX: Fold tdx_bringup() into tdx_hardware_setup()

[Sean Christopherson <seanjc@google.com>]

Now that TDX doesn't need to manually enable virtualization through _KVM_
APIs during setup, fold tdx_bringup() into tdx_hardware_setup() where the
code belongs, e.g. so that KVM doesn't leave the S-EPT kvm_x86_ops wired
up when TDX is disabled.

The weird ordering (and naming) was necessary to allow KVM TDX to use
kvm_enable_virtualization(), which in turn had a hard dependency on
kvm_x86_ops.enable_virtualization_cpu and thus kvm_x86_vendor_init().

Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/kvm/vmx/main.c | 19 ++++++++-----------
 arch/x86/kvm/vmx/tdx.c  | 39 +++++++++++++++------------------------
 arch/x86/kvm/vmx/tdx.h  |  8 ++------
 3 files changed, 25 insertions(+), 41 deletions(-)

diff --git a/arch/x86/kvm/vmx/main.c b/arch/x86/kvm/vmx/main.c
index a46ccd670785..dbebddf648be 100644
--- a/arch/x86/kvm/vmx/main.c
+++ b/arch/x86/kvm/vmx/main.c
@@ -29,10 +29,15 @@ static __init int vt_hardware_setup(void)
 	if (ret)
 		return ret;
 
+	return enable_tdx ? tdx_hardware_setup() : 0;
+}
+
+static void vt_hardware_unsetup(void)
+{
 	if (enable_tdx)
-		tdx_hardware_setup();
+		tdx_hardware_unsetup();
 
-	return 0;
+	vmx_hardware_unsetup();
 }
 
 static int vt_vm_init(struct kvm *kvm)
@@ -869,7 +874,7 @@ struct kvm_x86_ops vt_x86_ops __initdata = {
 
 	.check_processor_compatibility = vmx_check_processor_compat,
 
-	.hardware_unsetup = vmx_hardware_unsetup,
+	.hardware_unsetup = vt_op(hardware_unsetup),
 
 	.enable_virtualization_cpu = vmx_enable_virtualization_cpu,
 	.disable_virtualization_cpu = vt_op(disable_virtualization_cpu),
@@ -1029,7 +1034,6 @@ struct kvm_x86_init_ops vt_init_ops __initdata = {
 static void __exit vt_exit(void)
 {
 	kvm_exit();
-	tdx_cleanup();
 	vmx_exit();
 }
 module_exit(vt_exit);
@@ -1043,11 +1047,6 @@ static int __init vt_init(void)
 	if (r)
 		return r;
 
-	/* tdx_init() has been taken */
-	r = tdx_bringup();
-	if (r)
-		goto err_tdx_bringup;
-
 	/*
 	 * TDX and VMX have different vCPU structures.  Calculate the
 	 * maximum size/align so that kvm_init() can use the larger
@@ -1074,8 +1073,6 @@ static int __init vt_init(void)
 	return 0;
 
 err_kvm_init:
-	tdx_cleanup();
-err_tdx_bringup:
 	vmx_exit();
 	return r;
 }
diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c
index fea3dfc7ac8b..d354022ba9c9 100644
--- a/arch/x86/kvm/vmx/tdx.c
+++ b/arch/x86/kvm/vmx/tdx.c
@@ -3285,7 +3285,12 @@ int tdx_gmem_max_mapping_level(struct kvm *kvm, kvm_pfn_t pfn, bool is_private)
 	return PG_LEVEL_4K;
 }
 
-static int __init __tdx_bringup(void)
+void tdx_hardware_unsetup(void)
+{
+	misc_cg_set_capacity(MISC_CG_RES_TDX, 0);
+}
+
+static int __init __tdx_hardware_setup(void)
 {
 	const struct tdx_sys_info_td_conf *td_conf;
 	int i;
@@ -3359,7 +3364,7 @@ static int __init __tdx_bringup(void)
 	return 0;
 }
 
-int __init tdx_bringup(void)
+int __init tdx_hardware_setup(void)
 {
 	int r, i;
 
@@ -3395,7 +3400,7 @@ int __init tdx_bringup(void)
 		goto success_disable_tdx;
 	}
 
-	r = __tdx_bringup();
+	r = __tdx_hardware_setup();
 	if (r) {
 		/*
 		 * Disable TDX only but don't fail to load module if the TDX
@@ -3409,31 +3414,12 @@ int __init tdx_bringup(void)
 		 */
 		if (r == -ENODEV)
 			goto success_disable_tdx;
+
+		return r;
 	}
 
-	return r;
-
-success_disable_tdx:
-	enable_tdx = 0;
-	return 0;
-}
-
-void tdx_cleanup(void)
-{
-	if (!enable_tdx)
-		return;
-
-	misc_cg_set_capacity(MISC_CG_RES_TDX, 0);
-}
-
-void __init tdx_hardware_setup(void)
-{
 	KVM_SANITY_CHECK_VM_STRUCT_SIZE(kvm_tdx);
 
-	/*
-	 * Note, if the TDX module can't be loaded, KVM TDX support will be
-	 * disabled but KVM will continue loading (see tdx_bringup()).
-	 */
 	vt_x86_ops.vm_size = max_t(unsigned int, vt_x86_ops.vm_size, sizeof(struct kvm_tdx));
 
 	vt_x86_ops.link_external_spt = tdx_sept_link_private_spt;
@@ -3441,4 +3427,9 @@ void __init tdx_hardware_setup(void)
 	vt_x86_ops.free_external_spt = tdx_sept_free_private_spt;
 	vt_x86_ops.remove_external_spte = tdx_sept_remove_private_spte;
 	vt_x86_ops.protected_apic_has_interrupt = tdx_protected_apic_has_interrupt;
+	return 0;
+
+success_disable_tdx:
+	enable_tdx = 0;
+	return 0;
 }
diff --git a/arch/x86/kvm/vmx/tdx.h b/arch/x86/kvm/vmx/tdx.h
index 45b5183ccb36..b5cd2ffb303e 100644
--- a/arch/x86/kvm/vmx/tdx.h
+++ b/arch/x86/kvm/vmx/tdx.h
@@ -8,9 +8,8 @@
 #ifdef CONFIG_KVM_INTEL_TDX
 #include "common.h"
 
-void tdx_hardware_setup(void);
-int tdx_bringup(void);
-void tdx_cleanup(void);
+int tdx_hardware_setup(void);
+void tdx_hardware_unsetup(void);
 
 extern bool enable_tdx;
 
@@ -187,9 +186,6 @@ TDX_BUILD_TDVPS_ACCESSORS(8, MANAGEMENT, management);
 TDX_BUILD_TDVPS_ACCESSORS(64, STATE_NON_ARCH, state_non_arch);
 
 #else
-static inline int tdx_bringup(void) { return 0; }
-static inline void tdx_cleanup(void) {}
-
 #define enable_tdx	0
 
 struct kvm_tdx {
-- 
2.53.0.310.g728cabbaf7-goog