KVM: VMX: unifdef the EFER specific code

To allow access to the EFER register in 32bit KVM the EFER specific code has to
be exported to the x86 generic code. This patch does this in a backwards
compatible manner.

[avi: add check for EFER-less hosts]
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

arch/x86/kvm/vmx.c

@@ -1335,14 +1335,14 @@ static void vmx_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
 	vcpu->arch.cr4 = cr4;
 }
 
-#ifdef CONFIG_X86_64
-
 static void vmx_set_efer(struct kvm_vcpu *vcpu, u64 efer)
 {
 	struct vcpu_vmx *vmx = to_vmx(vcpu);
 	struct kvm_msr_entry *msr = find_msr_entry(vmx, MSR_EFER);
 
 	vcpu->arch.shadow_efer = efer;
+	if (!msr)
+		return;
 	if (efer & EFER_LMA) {
 		vmcs_write32(VM_ENTRY_CONTROLS,
 				     vmcs_read32(VM_ENTRY_CONTROLS) |
@@ -1359,8 +1359,6 @@ static void vmx_set_efer(struct kvm_vcpu *vcpu, u64 efer)
 	setup_msrs(vmx);
 }
 
-#endif
-
 static u64 vmx_get_segment_base(struct kvm_vcpu *vcpu, int seg)
 {
 	struct kvm_vmx_segment_field *sf = &kvm_vmx_segment_fields[seg];
@@ -1775,9 +1773,7 @@ static int vmx_vcpu_reset(struct kvm_vcpu *vcpu)
 	vmx->vcpu.arch.cr0 = 0x60000010;
 	vmx_set_cr0(&vmx->vcpu, vmx->vcpu.arch.cr0); /* enter rmode */
 	vmx_set_cr4(&vmx->vcpu, 0);
-#ifdef CONFIG_X86_64
 	vmx_set_efer(&vmx->vcpu, 0);
-#endif
 	vmx_fpu_activate(&vmx->vcpu);
 	update_exception_bitmap(&vmx->vcpu);
 
@@ -2668,9 +2664,7 @@ static struct kvm_x86_ops vmx_x86_ops = {
 	.set_cr0 = vmx_set_cr0,
 	.set_cr3 = vmx_set_cr3,
 	.set_cr4 = vmx_set_cr4,
-#ifdef CONFIG_X86_64
 	.set_efer = vmx_set_efer,
-#endif
 	.get_idt = vmx_get_idt,
 	.set_idt = vmx_set_idt,
 	.get_gdt = vmx_get_gdt,