[PATCH v2 1/3] KVM: SVM: Make kvm_x86_ops.vcpu_precreate() hook fully AVIC specific

[Sean Christopherson]

In anticipation of deferring all per-VM AVIC initialization until a vCPU
is first created, move SVM's kvm_x86_ops.vcpu_precreate() hook into avic.c
as avic_vcpu_pre_create() and nullify the hook if AVIC is disabled (and
WARN if the hook is somehow invoked without AVIC enabled).

Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
 arch/x86/kvm/svm/avic.c | 13 +++++++++----
 arch/x86/kvm/svm/svm.c  |  8 ++------
 arch/x86/kvm/svm/svm.h  |  2 +-
 3 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c
index 58e493a80cb0..4a0a2dbd1687 100644
--- a/arch/x86/kvm/svm/avic.c
+++ b/arch/x86/kvm/svm/avic.c
@@ -293,13 +293,10 @@ static int avic_get_physical_id_table_order(struct kvm *kvm)
 	return get_order((__avic_get_max_physical_id(kvm, NULL) + 1) * sizeof(u64));
 }
 
-int avic_alloc_physical_id_table(struct kvm *kvm)
+static int avic_alloc_physical_id_table(struct kvm *kvm)
 {
 	struct kvm_svm *kvm_svm = to_kvm_svm(kvm);
 
-	if (!irqchip_in_kernel(kvm) || !enable_apicv)
-		return 0;
-
 	if (kvm_svm->avic_physical_id_table)
 		return 0;
 
@@ -311,6 +308,14 @@ int avic_alloc_physical_id_table(struct kvm *kvm)
 	return 0;
 }
 
+int avic_vcpu_precreate(struct kvm *kvm)
+{
+	if (!irqchip_in_kernel(kvm) || WARN_ON_ONCE(!enable_apicv))
+		return 0;
+
+	return avic_alloc_physical_id_table(kvm);
+}
+
 void avic_vm_destroy(struct kvm *kvm)
 {
 	unsigned long flags;
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index ef69a51ab27f..a7d141f7e76c 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -1306,11 +1306,6 @@ void svm_switch_vmcb(struct vcpu_svm *svm, struct kvm_vmcb_info *target_vmcb)
 	svm->vmcb = target_vmcb->ptr;
 }
 
-static int svm_vcpu_precreate(struct kvm *kvm)
-{
-	return avic_alloc_physical_id_table(kvm);
-}
-
 static int svm_vcpu_create(struct kvm_vcpu *vcpu)
 {
 	struct vcpu_svm *svm;
@@ -5333,7 +5328,7 @@ struct kvm_x86_ops svm_x86_ops __initdata = {
 	.emergency_disable_virtualization_cpu = svm_emergency_disable_virtualization_cpu,
 	.has_emulated_msr = svm_has_emulated_msr,
 
-	.vcpu_precreate = svm_vcpu_precreate,
+	.vcpu_precreate = avic_vcpu_precreate,
 	.vcpu_create = svm_vcpu_create,
 	.vcpu_free = svm_vcpu_free,
 	.vcpu_reset = svm_vcpu_reset,
@@ -5712,6 +5707,7 @@ static __init int svm_hardware_setup(void)
 	enable_apicv = avic_hardware_setup();
 	if (!enable_apicv) {
 		enable_ipiv = false;
+		svm_x86_ops.vcpu_precreate = NULL;
 		svm_x86_ops.vcpu_blocking = NULL;
 		svm_x86_ops.vcpu_unblocking = NULL;
 		svm_x86_ops.vcpu_get_apicv_inhibit_reasons = NULL;
diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
index 716be21fba33..3c5459374969 100644
--- a/arch/x86/kvm/svm/svm.h
+++ b/arch/x86/kvm/svm/svm.h
@@ -945,7 +945,7 @@ extern struct kvm_x86_nested_ops svm_nested_ops;
 
 bool __init avic_hardware_setup(void);
 void avic_hardware_unsetup(void);
-int avic_alloc_physical_id_table(struct kvm *kvm);
+int avic_vcpu_precreate(struct kvm *kvm);
 void avic_vm_destroy(struct kvm *kvm);
 int avic_vm_init(struct kvm *kvm);
 void avic_init_vmcb(struct vcpu_svm *svm, struct vmcb *vmcb);
-- 
2.55.0.rc0.799.gd6f94ed593-goog