KVM: x86: Uninline and export hv_track_root_tdp()

Uninline and export Hyper-V's hv_track_root_tdp(), which is (somewhat
indirectly) the last remaining reference to kvm_x86_ops from vendor
modules, i.e. will allow unexporting kvm_x86_ops.  Reloading the TDP PGD
isn't the fastest of paths, hv_track_root_tdp() isn't exactly tiny, and
disallowing vendor code from accessing kvm_x86_ops provides nice-to-have
encapsulation of common x86 code (and of Hyper-V code for that matter).

No functional change intended.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220128005208.4008533-10-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/kvm_onhyperv.c

@@ -92,3 +92,17 @@ int hv_remote_flush_tlb(struct kvm *kvm)
 	return hv_remote_flush_tlb_with_range(kvm, NULL);
 }
 EXPORT_SYMBOL_GPL(hv_remote_flush_tlb);
+
+void hv_track_root_tdp(struct kvm_vcpu *vcpu, hpa_t root_tdp)
+{
+	struct kvm_arch *kvm_arch = &vcpu->kvm->arch;
+
+	if (kvm_x86_ops.tlb_remote_flush == hv_remote_flush_tlb) {
+		spin_lock(&kvm_arch->hv_root_tdp_lock);
+		vcpu->arch.hv_root_tdp = root_tdp;
+		if (root_tdp != kvm_arch->hv_root_tdp)
+			kvm_arch->hv_root_tdp = INVALID_PAGE;
+		spin_unlock(&kvm_arch->hv_root_tdp_lock);
+	}
+}
+EXPORT_SYMBOL_GPL(hv_track_root_tdp);

arch/x86/kvm/kvm_onhyperv.h

@@ -10,19 +10,7 @@
 int hv_remote_flush_tlb_with_range(struct kvm *kvm,
 		struct kvm_tlb_range *range);
 int hv_remote_flush_tlb(struct kvm *kvm);
-
-static inline void hv_track_root_tdp(struct kvm_vcpu *vcpu, hpa_t root_tdp)
-{
-	struct kvm_arch *kvm_arch = &vcpu->kvm->arch;
-
-	if (kvm_x86_ops.tlb_remote_flush == hv_remote_flush_tlb) {
-		spin_lock(&kvm_arch->hv_root_tdp_lock);
-		vcpu->arch.hv_root_tdp = root_tdp;
-		if (root_tdp != kvm_arch->hv_root_tdp)
-			kvm_arch->hv_root_tdp = INVALID_PAGE;
-		spin_unlock(&kvm_arch->hv_root_tdp_lock);
-	}
-}
+void hv_track_root_tdp(struct kvm_vcpu *vcpu, hpa_t root_tdp);
 #else /* !CONFIG_HYPERV */
 static inline void hv_track_root_tdp(struct kvm_vcpu *vcpu, hpa_t root_tdp)
 {