KVM: nSVM: Use KVM-governed feature framework to track "Pause Filter enabled"

Track "Pause Filtering is exposed to L1" via governed feature flags
instead of using dedicated bits/flags in vcpu_svm.

No functional change intended.

Reviewed-by: Yuan Yao <yuan.yao@intel.com>
Link: https://lore.kernel.org/r/20230815203653.519297-13-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

Author: sean-jc

arch/x86/kvm/governed_features.h

@@ -12,6 +12,8 @@ KVM_GOVERNED_X86_FEATURE(NRIPS)
 KVM_GOVERNED_X86_FEATURE(TSCRATEMSR)
 KVM_GOVERNED_X86_FEATURE(V_VMSAVE_VMLOAD)
 KVM_GOVERNED_X86_FEATURE(LBRV)
+KVM_GOVERNED_X86_FEATURE(PAUSEFILTER)
+KVM_GOVERNED_X86_FEATURE(PFTHRESHOLD)
 
 #undef KVM_GOVERNED_X86_FEATURE
 #undef KVM_GOVERNED_FEATURE

arch/x86/kvm/svm/nested.c

@@ -743,8 +743,14 @@ static void nested_vmcb02_prepare_control(struct vcpu_svm *svm,
 	if (!nested_vmcb_needs_vls_intercept(svm))
 		vmcb02->control.virt_ext |= VIRTUAL_VMLOAD_VMSAVE_ENABLE_MASK;
 
-	pause_count12 = svm->pause_filter_enabled ? svm->nested.ctl.pause_filter_count : 0;
-	pause_thresh12 = svm->pause_threshold_enabled ? svm->nested.ctl.pause_filter_thresh : 0;
+	if (guest_can_use(vcpu, X86_FEATURE_PAUSEFILTER))
+		pause_count12 = svm->nested.ctl.pause_filter_count;
+	else
+		pause_count12 = 0;
+	if (guest_can_use(vcpu, X86_FEATURE_PFTHRESHOLD))
+		pause_thresh12 = svm->nested.ctl.pause_filter_thresh;
+	else
+		pause_thresh12 = 0;
 	if (kvm_pause_in_guest(svm->vcpu.kvm)) {
 		/* use guest values since host doesn't intercept PAUSE */
 		vmcb02->control.pause_filter_count = pause_count12;

arch/x86/kvm/svm/svm.c

@@ -4271,11 +4271,8 @@ static void svm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu)
 	if (!guest_cpuid_is_intel(vcpu))
 		kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_V_VMSAVE_VMLOAD);
 
-	svm->pause_filter_enabled = kvm_cpu_cap_has(X86_FEATURE_PAUSEFILTER) &&
-			guest_cpuid_has(vcpu, X86_FEATURE_PAUSEFILTER);
-
-	svm->pause_threshold_enabled = kvm_cpu_cap_has(X86_FEATURE_PFTHRESHOLD) &&
-			guest_cpuid_has(vcpu, X86_FEATURE_PFTHRESHOLD);
+	kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_PAUSEFILTER);
+	kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_PFTHRESHOLD);
 
 	svm->vgif_enabled = vgif && guest_cpuid_has(vcpu, X86_FEATURE_VGIF);
 

arch/x86/kvm/svm/svm.h

@@ -259,8 +259,6 @@ struct vcpu_svm {
 	bool soft_int_injected;
 
 	/* optional nested SVM features that are enabled for this guest  */
-	bool pause_filter_enabled         : 1;
-	bool pause_threshold_enabled      : 1;
 	bool vgif_enabled                 : 1;
 	bool vnmi_enabled                 : 1;