KVM: VMX: introduce alloc_loaded_vmcs

Group together the calls to alloc_vmcs and loaded_vmcs_init.  Soon we'll also
allocate an MSR bitmap there.

Cc: stable@vger.kernel.org       # prereq for Spectre mitigation
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index ad6a883..ab4b9bc 100644 (file)
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -3829,11 +3829,6 @@ static struct vmcs *alloc_vmcs_cpu(int cpu)
        return vmcs;
 }
 
-static struct vmcs *alloc_vmcs(void)
-{
-       return alloc_vmcs_cpu(raw_smp_processor_id());
-}
-
 static void free_vmcs(struct vmcs *vmcs)
 {
        free_pages((unsigned long)vmcs, vmcs_config.order);
@@ -3852,6 +3847,22 @@ static void free_loaded_vmcs(struct loaded_vmcs *loaded_vmcs)
        WARN_ON(loaded_vmcs->shadow_vmcs != NULL);
 }
 
+static struct vmcs *alloc_vmcs(void)
+{
+       return alloc_vmcs_cpu(raw_smp_processor_id());
+}
+
+static int alloc_loaded_vmcs(struct loaded_vmcs *loaded_vmcs)
+{
+       loaded_vmcs->vmcs = alloc_vmcs();
+       if (!loaded_vmcs->vmcs)
+               return -ENOMEM;
+
+       loaded_vmcs->shadow_vmcs = NULL;
+       loaded_vmcs_init(loaded_vmcs);
+       return 0;
+}
+
 static void free_kvm_area(void)
 {
        int cpu;
@@ -7145,12 +7156,11 @@ static int enter_vmx_operation(struct kvm_vcpu *vcpu)
 {
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        struct vmcs *shadow_vmcs;
+       int r;
 
-       vmx->nested.vmcs02.vmcs = alloc_vmcs();
-       vmx->nested.vmcs02.shadow_vmcs = NULL;
-       if (!vmx->nested.vmcs02.vmcs)
+       r = alloc_loaded_vmcs(&vmx->nested.vmcs02);
+       if (r < 0)
                goto out_vmcs02;
-       loaded_vmcs_init(&vmx->nested.vmcs02);
 
        if (cpu_has_vmx_msr_bitmap()) {
                vmx->nested.msr_bitmap =
@@ -9545,13 +9555,11 @@ static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, unsigned int id)
        if (!vmx->guest_msrs)
                goto free_pml;
 
-       vmx->loaded_vmcs = &vmx->vmcs01;
-       vmx->loaded_vmcs->vmcs = alloc_vmcs();
-       vmx->loaded_vmcs->shadow_vmcs = NULL;
-       if (!vmx->loaded_vmcs->vmcs)
+       err = alloc_loaded_vmcs(&vmx->vmcs01);
+       if (err < 0)
                goto free_msrs;
-       loaded_vmcs_init(vmx->loaded_vmcs);
 
+       vmx->loaded_vmcs = &vmx->vmcs01;
        cpu = get_cpu();
        vmx_vcpu_load(&vmx->vcpu, cpu);
        vmx->vcpu.cpu = cpu;