[PATCH v5 09/18] kvm: x86: Introduce x86 ops hook for pre-update APICv

[Suravee Suthikulpanit]

AMD SVM AVIC needs to update APIC backing page mapping before changing
APICv mode. Introduce struct kvm_x86_ops.pre_update_apicv_exec_ctrl
function hook to be called prior KVM APICv update request to each vcpu.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
---
 arch/x86/include/asm/kvm_host.h | 1 +
 arch/x86/kvm/svm.c              | 6 ++++++
 arch/x86/kvm/x86.c              | 2 ++
 3 files changed, 9 insertions(+)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 5ee6331..c685643 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1091,6 +1091,7 @@ struct kvm_x86_ops {
 	void (*update_cr8_intercept)(struct kvm_vcpu *vcpu, int tpr, int irr);
 	bool (*get_enable_apicv)(struct kvm *kvm);
 	bool (*check_apicv_inhibit_reasons)(ulong bit);
+	void (*pre_update_apicv_exec_ctrl)(struct kvm *kvm, bool activate);
 	void (*refresh_apicv_exec_ctrl)(struct kvm_vcpu *vcpu);
 	void (*hwapic_irr_update)(struct kvm_vcpu *vcpu, int max_irr);
 	void (*hwapic_isr_update)(struct kvm_vcpu *vcpu, int isr);
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 8bffd93..5a4516c 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -7230,6 +7230,11 @@ static bool svm_check_apicv_inhibit_reasons(ulong bit)
 	return supported & BIT(bit);
 }
 
+static void svm_pre_update_apicv_exec_ctrl(struct kvm *kvm, bool activate)
+{
+	avic_update_access_page(kvm, activate);
+}
+
 static struct kvm_x86_ops svm_x86_ops __ro_after_init = {
 	.cpu_has_kvm_support = has_svm,
 	.disabled_by_bios = is_disabled,
@@ -7308,6 +7313,7 @@ static bool svm_check_apicv_inhibit_reasons(ulong bit)
 	.get_enable_apicv = svm_get_enable_apicv,
 	.refresh_apicv_exec_ctrl = svm_refresh_apicv_exec_ctrl,
 	.check_apicv_inhibit_reasons = svm_check_apicv_inhibit_reasons,
+	.pre_update_apicv_exec_ctrl = svm_pre_update_apicv_exec_ctrl,
 	.load_eoi_exitmap = svm_load_eoi_exitmap,
 	.hwapic_irr_update = svm_hwapic_irr_update,
 	.hwapic_isr_update = svm_hwapic_isr_update,
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 1ab8e66..cbc7884 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -7897,6 +7897,8 @@ void kvm_request_apicv_update(struct kvm *kvm, bool activate, ulong bit)
 	}
 
 	trace_kvm_apicv_update_request(activate, bit);
+	if (kvm_x86_ops->pre_update_apicv_exec_ctrl)
+		kvm_x86_ops->pre_update_apicv_exec_ctrl(kvm, activate);
 	kvm_make_all_cpus_request(kvm, KVM_REQ_APICV_UPDATE);
 }
 EXPORT_SYMBOL_GPL(kvm_request_apicv_update);
-- 
1.8.3.1