[PATCH v3 06/16] kvm: x86: svm: Add support to activate/deactivate posted interrupts

[Suthikulpanit, Suravee]

Introduce interface for activate/deactivate posted interrupts, and
implement SVM hooks to toggle AMD IOMMU guest virtual APIC mode.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
---
 arch/x86/include/asm/kvm_host.h |  4 ++++
 arch/x86/kvm/svm.c              | 44 +++++++++++++++++++++++++++++++++++++++++
 arch/x86/kvm/x86.c              |  5 +++++
 3 files changed, 53 insertions(+)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index a50fca1b..624e883 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1193,6 +1193,10 @@ struct kvm_x86_ops {
 
 	int (*update_pi_irte)(struct kvm *kvm, unsigned int host_irq,
 			      uint32_t guest_irq, bool set);
+
+	int (*activate_pi_irte)(struct kvm_vcpu *vcpu);
+	int (*deactivate_pi_irte)(struct kvm_vcpu *vcpu);
+
 	void (*apicv_post_state_restore)(struct kvm_vcpu *vcpu);
 	bool (*dy_apicv_has_pending_interrupt)(struct kvm_vcpu *vcpu);
 
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 245bde0..8673617 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -5398,6 +5398,48 @@ static int svm_update_pi_irte(struct kvm *kvm, unsigned int host_irq,
 	return ret;
 }
 
+static int svm_set_pi_irte_mode(struct kvm_vcpu *vcpu, bool activate)
+{
+	int ret = 0;
+	unsigned long flags;
+	struct amd_svm_iommu_ir *ir;
+	struct vcpu_svm *svm = to_svm(vcpu);
+
+	if (!kvm_arch_has_assigned_device(vcpu->kvm))
+		return 0;
+
+	/*
+	 * Here, we go through the per-vcpu ir_list to update all existing
+	 * interrupt remapping table entry targeting this vcpu.
+	 */
+	spin_lock_irqsave(&svm->ir_list_lock, flags);
+
+	if (list_empty(&svm->ir_list))
+		goto out;
+
+	list_for_each_entry(ir, &svm->ir_list, node) {
+		if (activate)
+			ret = amd_iommu_activate_guest_mode(ir->data);
+		else
+			ret = amd_iommu_deactivate_guest_mode(ir->data);
+		if (ret)
+			break;
+	}
+out:
+	spin_unlock_irqrestore(&svm->ir_list_lock, flags);
+	return ret;
+}
+
+static int svm_activate_pi_irte(struct kvm_vcpu *vcpu)
+{
+	return svm_set_pi_irte_mode(vcpu, true);
+}
+
+static int svm_deactivate_pi_irte(struct kvm_vcpu *vcpu)
+{
+	return svm_set_pi_irte_mode(vcpu, false);
+}
+
 static int svm_nmi_allowed(struct kvm_vcpu *vcpu)
 {
 	struct vcpu_svm *svm = to_svm(vcpu);
@@ -7321,6 +7363,8 @@ static bool svm_need_emulation_on_page_fault(struct kvm_vcpu *vcpu)
 	.deliver_posted_interrupt = svm_deliver_avic_intr,
 	.dy_apicv_has_pending_interrupt = svm_dy_apicv_has_pending_interrupt,
 	.update_pi_irte = svm_update_pi_irte,
+	.activate_pi_irte = svm_activate_pi_irte,
+	.deactivate_pi_irte = svm_deactivate_pi_irte,
 	.setup_mce = svm_setup_mce,
 
 	.smi_allowed = svm_smi_allowed,
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index bc74876..1540629 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -7198,6 +7198,9 @@ void kvm_vcpu_activate_apicv(struct kvm_vcpu *vcpu)
 	kvm_apic_update_apicv(vcpu);
 
 	kvm_x86_ops->refresh_apicv_exec_ctrl(vcpu);
+
+	if (kvm_x86_ops->activate_pi_irte)
+		kvm_x86_ops->activate_pi_irte(vcpu);
 }
 EXPORT_SYMBOL_GPL(kvm_vcpu_activate_apicv);
 
@@ -7212,6 +7215,8 @@ void kvm_vcpu_deactivate_apicv(struct kvm_vcpu *vcpu)
 
 	vcpu->arch.apicv_active = false;
 	kvm_apic_update_apicv(vcpu);
+	if (kvm_x86_ops->deactivate_pi_irte)
+		kvm_x86_ops->deactivate_pi_irte(vcpu);
 	kvm_x86_ops->refresh_apicv_exec_ctrl(vcpu);
 }
 EXPORT_SYMBOL_GPL(kvm_vcpu_deactivate_apicv);
-- 
1.8.3.1