This patch implements update_pi_irte function hook to allow SVM
communicate to IOMMU driver regarding how to set up IRTE for handling
posted interrupt.
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpa...@amd.com>
---
arch/x86/kvm/svm.c | 107 +++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 107 insertions(+)
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index a0aaaa6..5a0b89a 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -43,6 +43,7 @@
#include <asm/desc.h>
#include <asm/debugreg.h>
#include <asm/kvm_para.h>
+#include <asm/irq_remapping.h>
#include <asm/virtext.h>
#include "trace.h"
@@ -1336,6 +1337,13 @@ static void avic_vm_destroy(struct kvm *kvm)
spin_unlock_irqrestore(&svm_vm_data_hash_lock, flags);
}
+static atomic_t avic_tag_gen = ATOMIC_INIT(0);
+
+static inline u32 avic_get_next_tag(void)
+{
+ return atomic_inc_return(&avic_tag_gen);
+}
+
static int avic_vm_init(struct kvm *kvm)
{
unsigned long flags;
@@ -1360,6 +1368,8 @@ static int avic_vm_init(struct kvm *kvm)
if (!l_page)
goto free_avic;
+ vm_data->avic_tag = avic_get_next_tag();
+
vm_data->avic_logical_id_table_page = l_page;
clear_page(page_address(l_page));
@@ -4297,6 +4307,102 @@ static void svm_deliver_avic_intr(struct kvm_vcpu
*vcpu, int vec)
kvm_vcpu_wake_up(vcpu);
}
+/*
+ * svm_update_pi_irte - set IRTE for Posted-Interrupts
+ *
+ * @kvm: kvm
+ * @host_irq: host irq of the interrupt
+ * @guest_irq: gsi of the interrupt
+ * @set: set or unset PI
+ * returns 0 on success, < 0 on failure
+ */
+static int svm_update_pi_irte(struct kvm *kvm, unsigned int host_irq,
+ uint32_t guest_irq, bool set)
+{
+ struct kvm_kernel_irq_routing_entry *e;
+ struct kvm_irq_routing_table *irq_rt;
+ struct kvm_lapic_irq irq;
+ struct kvm_vcpu *vcpu = NULL;
+ struct vcpu_data vcpu_info;
+ int idx, ret = -EINVAL;
+ struct vcpu_svm *svm;
+ struct amd_iommu_pi_data pi_data;
+
+ if (!kvm_arch_has_assigned_device(kvm) ||
+ !irq_remapping_cap(IRQ_POSTING_CAP))
+ return 0;
+
+ pr_debug("SVM: %s: host_irq=%#x, guest_irq=%#x, set=%#x\n",
+ __func__, host_irq, guest_irq, set);
+
+ idx = srcu_read_lock(&kvm->irq_srcu);
+ irq_rt = srcu_dereference(kvm->irq_routing, &kvm->irq_srcu);
+ WARN_ON(guest_irq >= irq_rt->nr_rt_entries);
+
+ hlist_for_each_entry(e, &irq_rt->map[guest_irq], link) {
+ if (e->type != KVM_IRQ_ROUTING_MSI)
+ continue;
+
+ /**
+ * Note:
+ * The HW cannot support posting multicast/broadcast
+ * interrupts to a vCPU. So, we still use interrupt
+ * remapping for these kind of interrupts.
+ *
+ * For lowest-priority interrupts, we only support
+ * those with single CPU as the destination, e.g. user
+ * configures the interrupts via /proc/irq or uses
+ * irqbalance to make the interrupts single-CPU.
+ */
+ kvm_set_msi_irq(e, &irq);
+ if (kvm_intr_is_single_vcpu(kvm, &irq, &vcpu)) {
+ svm = to_svm(vcpu);
+ vcpu_info.pi_desc_addr =
page_to_phys(svm->avic_backing_page);
+ vcpu_info.vector = irq.vector;
+
+ trace_kvm_pi_irte_update(vcpu->vcpu_id, host_irq,
e->gsi,
+ vcpu_info.vector,
+ vcpu_info.pi_desc_addr, set);
+
+ pi_data.vcpu_id = vcpu->vcpu_id;
+
+ pr_debug("SVM: %s: use GA mode for irq %u\n", __func__,
+ irq.vector);
+ } else {
+ set = false;
+
+ pr_debug("SVM: %s: use legacy intr remap mode for irq
%u\n",
+ __func__, irq.vector);
+ }
+
+ /**
+ * Note:
+ * When AVIC is disabled, we fall-back to setup
+ * IRTE w/ legacy mode
+ */
+ if (set && kvm_vcpu_apicv_active(&svm->vcpu)) {
+ /* Enable GA mode in IRTE */
+ pi_data.avic_tag = kvm->arch.avic_tag;
+ pi_data.vcpu_data = &vcpu_info;
+ ret = irq_set_vcpu_affinity(host_irq, &pi_data);
+ } else {
+ /* Use legacy mode in IRTE */
+ pi_data.vcpu_data = NULL;
+ ret = irq_set_vcpu_affinity(host_irq, &pi_data);
+ }
+
+ if (ret < 0) {
+ pr_err("%s: failed to update PI IRTE\n", __func__);
+ goto out;
+ }
+ }
+
+ ret = 0;
+out:
+ srcu_read_unlock(&kvm->irq_srcu, idx);
+ return ret;
+}
+
static int svm_nmi_allowed(struct kvm_vcpu *vcpu)
{
struct vcpu_svm *svm = to_svm(vcpu);
@@ -5123,6 +5229,7 @@ static struct kvm_x86_ops svm_x86_ops = {
.pmu_ops = &amd_pmu_ops,
.deliver_posted_interrupt = svm_deliver_avic_intr,
+ .update_pi_irte = svm_update_pi_irte,
};
static int __init svm_init(void)
--
1.9.1
