KVM: VMX: Use vpid_sync_context() directly when possible

Use vpid_sync_context() directly for flows that run if and only if
enable_vpid=1, or more specifically, nested VMX flows that are gated by
vmx->nested.msrs.secondary_ctls_high.SECONDARY_EXEC_ENABLE_VPID being
set, which is allowed if and only if enable_vpid=1.  Because these flows
call __vmx_flush_tlb() with @invalidate_gpa=false, the if-statement that
decides between INVEPT and INVVPID will always go down the INVVPID path,
i.e. call vpid_sync_context() because
"enable_ept && (invalidate_gpa || !enable_vpid)" always evaluates false.

This helps pave the way toward removing @invalidate_gpa and @vpid from
__vmx_flush_tlb() and its callers.

Opportunstically drop unnecessary brackets in handle_invvpid() around an
affected __vmx_flush_tlb()->vpid_sync_context() conversion.

No functional change intended.
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200320212833.3507-10-sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/vmx/nested.c

@@ -2459,7 +2459,7 @@ static int prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12,
 		if (nested_cpu_has_vpid(vmcs12) && nested_has_guest_tlb_tag(vcpu)) {
 			if (vmcs12->virtual_processor_id != vmx->nested.last_vpid) {
 				vmx->nested.last_vpid = vmcs12->virtual_processor_id;
-				__vmx_flush_tlb(vcpu, nested_get_vpid02(vcpu), false);
+				vpid_sync_context(nested_get_vpid02(vcpu));
 			}
 		} else {
 			/*
@@ -5234,21 +5234,21 @@ static int handle_invvpid(struct kvm_vcpu *vcpu)
 		    is_noncanonical_address(operand.gla, vcpu))
 			return nested_vmx_failValid(vcpu,
 				VMXERR_INVALID_OPERAND_TO_INVEPT_INVVPID);
-		if (cpu_has_vmx_invvpid_individual_addr()) {
+		if (cpu_has_vmx_invvpid_individual_addr())
 			__invvpid(VMX_VPID_EXTENT_INDIVIDUAL_ADDR,
 				vpid02, operand.gla);
-		} else
-			__vmx_flush_tlb(vcpu, vpid02, false);
+		else
+			vpid_sync_context(vpid02);
 		break;
 	case VMX_VPID_EXTENT_SINGLE_CONTEXT:
 	case VMX_VPID_EXTENT_SINGLE_NON_GLOBAL:
 		if (!operand.vpid)
 			return nested_vmx_failValid(vcpu,
 				VMXERR_INVALID_OPERAND_TO_INVEPT_INVVPID);
-		__vmx_flush_tlb(vcpu, vpid02, false);
+		vpid_sync_context(vpid02);
 		break;
 	case VMX_VPID_EXTENT_ALL_CONTEXT:
-		__vmx_flush_tlb(vcpu, vpid02, false);
+		vpid_sync_context(vpid02);
 		break;
 	default:
 		WARN_ON_ONCE(1);