[PATCH 6/7] KVM: nVMX: Move the checks for Host Control Registers and MSRs to a separate helper function

[Krish Sadhukhan <krish.sadhukhan@xxxxxxxxxx>]

.. to improve readability and maintainability, and to align the code as per
the layout of the checks in chapter "VM Entries" in Intel SDM vol 3C.

Signed-off-by: Krish Sadhukhan <krish.sadhukhan@xxxxxxxxxx>
Reviewed-by: Mihai Carabas <mihai.carabas@xxxxxxxxxx>
Reviewed-by: Mark Kanda <mark.kanda@xxxxxxxxxx>
---
 arch/x86/kvm/vmx.c | 39 +++++++++++++++++++++++++--------------
 1 file changed, 25 insertions(+), 14 deletions(-)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index a428bfd..9273f3e 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -13134,25 +13134,18 @@ static int nested_check_vm_entry_controls(struct kvm_vcpu *vcpu,
 	return 0;
 }
 
-static int nested_check_vmentry_prereqs(struct kvm_vcpu *vcpu,
-					struct vmcs12 *vmcs12)
+/*
+ * Checks related to Host Control Registers and MSRs
+ */
+static int nested_check_host_control_regs(struct kvm_vcpu *vcpu,
+                                          struct vmcs12 *vmcs12)
 {
 	bool ia32e;
 
-	if (vmcs12->guest_activity_state != GUEST_ACTIVITY_ACTIVE &&
-	    vmcs12->guest_activity_state != GUEST_ACTIVITY_HLT)
-		return VMXERR_ENTRY_INVALID_CONTROL_FIELD;
-
-	if (nested_check_vm_execution_controls(vcpu, vmcs12) ||
-	    nested_check_vm_exit_controls(vcpu, vmcs12) ||
-	    nested_check_vm_entry_controls(vcpu, vmcs12))
-		return VMXERR_ENTRY_INVALID_CONTROL_FIELD;
-
 	if (!nested_host_cr0_valid(vcpu, vmcs12->host_cr0) ||
 	    !nested_host_cr4_valid(vcpu, vmcs12->host_cr4) ||
 	    !nested_cr3_valid(vcpu, vmcs12->host_cr3))
-		return VMXERR_ENTRY_INVALID_HOST_STATE_FIELD;
-
+		return -EINVAL;
 	/*
 	 * If the load IA32_EFER VM-exit control is 1, bits reserved in the
 	 * IA32_EFER MSR must be 0 in the field for that register. In addition,
@@ -13165,12 +13158,30 @@ static int nested_check_vmentry_prereqs(struct kvm_vcpu *vcpu,
 		if (!kvm_valid_efer(vcpu, vmcs12->host_ia32_efer) ||
 		    ia32e != !!(vmcs12->host_ia32_efer & EFER_LMA) ||
 		    ia32e != !!(vmcs12->host_ia32_efer & EFER_LME))
-			return VMXERR_ENTRY_INVALID_HOST_STATE_FIELD;
+			return -EINVAL;
 	}
 
 	return 0;
 }
 
+static int nested_check_vmentry_prereqs(struct kvm_vcpu *vcpu,
+					struct vmcs12 *vmcs12)
+{
+	if (vmcs12->guest_activity_state != GUEST_ACTIVITY_ACTIVE &&
+	    vmcs12->guest_activity_state != GUEST_ACTIVITY_HLT)
+		return VMXERR_ENTRY_INVALID_CONTROL_FIELD;
+
+	if (nested_check_vm_execution_controls(vcpu, vmcs12) ||
+	    nested_check_vm_exit_controls(vcpu, vmcs12) ||
+	    nested_check_vm_entry_controls(vcpu, vmcs12))
+		return VMXERR_ENTRY_INVALID_CONTROL_FIELD;
+
+	if (nested_check_host_control_regs(vcpu, vmcs12))
+		return VMXERR_ENTRY_INVALID_HOST_STATE_FIELD;
+
+	return 0;
+}
+
 static int nested_vmx_check_vmcs_link_ptr(struct kvm_vcpu *vcpu,
 					  struct vmcs12 *vmcs12)
 {
-- 
2.9.5