@@ -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"
@@ -200,6 +201,23 @@ struct vcpu_svm {
struct page *avic_backing_page;
u64 *avic_physical_id_cache;
bool avic_is_running;
+
+ /*
+ * Per-vcpu list of struct amd_svm_iommu_ir:
+ * This is used mainly to store interrupt remapping information used
+ * when update the vcpu affinity. This avoids the need to scan for
+ * IRTE and try to match ga_tag in the IOMMU driver.
+ */
+ struct list_head ir_list;
+ spinlock_t ir_list_lock;
+};
+
+/*
+ * This is a wrapper of struct amd_iommu_ir_data.
+ */
+struct amd_svm_iommu_ir {
+ struct list_head node; /* Used by SVM for per-vcpu ir_list */
+ void *data; /* Storing pointer to struct amd_ir_data */
};
#define AVIC_LOGICAL_ID_ENTRY_GUEST_PHYSICAL_ID_MASK (0xFF)
@@ -1440,31 +1458,34 @@ free_avic:
return err;
}
-/**
- * This function is called during VCPU halt/unhalt.
- */
-static void avic_set_running(struct kvm_vcpu *vcpu, bool is_run)
+static inline int
+avic_update_iommu_vcpu_affinity(struct kvm_vcpu *vcpu, int cpu, bool r)
{
- u64 entry;
- int h_physical_id = kvm_cpu_get_apicid(vcpu->cpu);
+ int ret = 0;
+ unsigned long flags;
+ struct amd_svm_iommu_ir *ir;
struct vcpu_svm *svm = to_svm(vcpu);
- if (!kvm_vcpu_apicv_active(vcpu))
- return;
-
- svm->avic_is_running = is_run;
+ if (!kvm_arch_has_assigned_device(vcpu->kvm))
+ return 0;
- /* ID = 0xff (broadcast), ID > 0xff (reserved) */
- if (WARN_ON(h_physical_id >= AVIC_MAX_PHYSICAL_ID_COUNT))
- return;
+ /*
+ * 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);
- entry = READ_ONCE(*(svm->avic_physical_id_cache));
- WARN_ON(is_run == !!(entry & AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK));
+ if (list_empty(&svm->ir_list))
+ goto out;
- entry &= ~AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK;
- if (is_run)
- entry |= AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK;
- WRITE_ONCE(*(svm->avic_physical_id_cache), entry);
+ list_for_each_entry(ir, &svm->ir_list, node) {
+ ret = amd_iommu_update_ga(cpu, r, ir->data);
+ if (ret)
+ break;
+ }
+out:
+ spin_unlock_irqrestore(&svm->ir_list_lock, flags);
+ return ret;
}
static void avic_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
@@ -1491,6 +1512,8 @@ static void avic_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
entry |= AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK;
WRITE_ONCE(*(svm->avic_physical_id_cache), entry);
+ avic_update_iommu_vcpu_affinity(vcpu, h_physical_id,
+ svm->avic_is_running);
}
static void avic_vcpu_put(struct kvm_vcpu *vcpu)
@@ -1502,10 +1525,27 @@ static void avic_vcpu_put(struct kvm_vcpu *vcpu)
return;
entry = READ_ONCE(*(svm->avic_physical_id_cache));
+ if (entry & AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK)
+ avic_update_iommu_vcpu_affinity(vcpu, -1, 0);
+
entry &= ~AVIC_PHYSICAL_ID_ENTRY_IS_RUNNING_MASK;
WRITE_ONCE(*(svm->avic_physical_id_cache), entry);
}
+/**
+ * This function is called during VCPU halt/unhalt.
+ */
+static void avic_set_running(struct kvm_vcpu *vcpu, bool is_run)
+{
+ struct vcpu_svm *svm = to_svm(vcpu);
+
+ svm->avic_is_running = is_run;
+ if (is_run)
+ avic_vcpu_load(vcpu, vcpu->cpu);
+ else
+ avic_vcpu_put(vcpu);
+}
+
static void svm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
{
struct vcpu_svm *svm = to_svm(vcpu);
@@ -1567,6 +1607,9 @@ static struct kvm_vcpu *svm_create_vcpu(struct kvm *kvm, unsigned int id)
err = avic_init_backing_page(&svm->vcpu);
if (err)
goto free_page4;
+
+ INIT_LIST_HEAD(&svm->ir_list);
+ spin_lock_init(&svm->ir_list_lock);
}
/* We initialize this flag to true to make sure that the is_running
@@ -4363,6 +4406,209 @@ static void svm_deliver_avic_intr(struct kvm_vcpu *vcpu, int vec)
kvm_vcpu_wake_up(vcpu);
}
+static void svm_ir_list_del(struct vcpu_svm *svm, struct amd_iommu_pi_data *pi)
+{
+ unsigned long flags;
+ struct amd_svm_iommu_ir *cur;
+
+ spin_lock_irqsave(&svm->ir_list_lock, flags);
+ list_for_each_entry(cur, &svm->ir_list, node) {
+ if (cur->data != pi->ir_data)
+ continue;
+ list_del(&cur->node);
+ kfree(cur);
+ break;
+ }
+ spin_unlock_irqrestore(&svm->ir_list_lock, flags);
+}
+
+static int svm_ir_list_add(struct vcpu_svm *svm, struct amd_iommu_pi_data *pi)
+{
+ int ret = 0;
+ unsigned long flags;
+ struct amd_svm_iommu_ir *ir;
+
+ /**
+ * In some cases, the existing irte is updaed and re-set,
+ * so we need to check here if it's already been * added
+ * to the ir_list.
+ */
+ if (pi->ir_data && (pi->prev_ga_tag != 0)) {
+ struct kvm *kvm = svm->vcpu.kvm;
+ u32 vcpu_id = AVIC_GATAG_TO_VCPUID(pi->prev_ga_tag);
+ struct kvm_vcpu *prev_vcpu = kvm_get_vcpu_by_id(kvm, vcpu_id);
+ struct vcpu_svm *prev_svm;
+
+ if (!prev_vcpu) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ prev_svm = to_svm(prev_vcpu);
+ svm_ir_list_del(prev_svm, pi);
+ }
+
+ /**
+ * Allocating new amd_iommu_pi_data, which will get
+ * add to the per-vcpu ir_list.
+ */
+ ir = kzalloc(sizeof(struct amd_svm_iommu_ir), GFP_KERNEL);
+ if (!ir) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ ir->data = pi->ir_data;
+
+ spin_lock_irqsave(&svm->ir_list_lock, flags);
+ list_add(&ir->node, &svm->ir_list);
+ spin_unlock_irqrestore(&svm->ir_list_lock, flags);
+out:
+ return ret;
+}
+
+/**
+ * Note:
+ * The HW cannot support posting multicast/broadcast
+ * interrupts to a vCPU. So, we still use legacy 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.
+ */
+static int
+get_pi_vcpu_info(struct kvm *kvm, struct kvm_kernel_irq_routing_entry *e,
+ struct vcpu_data *vcpu_info, struct vcpu_svm **svm)
+{
+ struct kvm_lapic_irq irq;
+ struct kvm_vcpu *vcpu = NULL;
+
+ kvm_set_msi_irq(e, &irq);
+
+ if (!kvm_intr_is_single_vcpu(kvm, &irq, &vcpu)) {
+ pr_debug("SVM: %s: use legacy intr remap mode for irq %u\n",
+ __func__, irq.vector);
+ return -1;
+ }
+
+ pr_debug("SVM: %s: use GA mode for irq %u\n", __func__,
+ irq.vector);
+ *svm = to_svm(vcpu);
+ vcpu_info->pi_desc_addr = page_to_phys((*svm)->avic_backing_page);
+ vcpu_info->vector = irq.vector;
+
+ return 0;
+}
+
+/*
+ * 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;
+ int idx, ret = -EINVAL;
+
+ 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) {
+ struct vcpu_data vcpu_info;
+ struct vcpu_svm *svm = NULL;
+
+ if (e->type != KVM_IRQ_ROUTING_MSI)
+ continue;
+
+ /**
+ * Here, we setup with legacy mode in the following cases:
+ * 1. When cannot target interrupt to a specific vcpu.
+ * 2. Unsetting posted interrupt.
+ * 3. APIC virtialization is disabled for the vcpu.
+ */
+ if (!get_pi_vcpu_info(kvm, e, &vcpu_info, &svm) && set &&
+ kvm_vcpu_apicv_active(&svm->vcpu)) {
+ struct amd_iommu_pi_data pi;
+
+ /* Try to enable guest_mode in IRTE */
+ pi.base = page_to_phys(svm->avic_backing_page) & AVIC_HPA_MASK;
+ pi.ga_tag = AVIC_GATAG(kvm->arch.avic_vm_id,
+ svm->vcpu.vcpu_id);
+ pi.is_guest_mode = true;
+ pi.vcpu_data = &vcpu_info;
+ ret = irq_set_vcpu_affinity(host_irq, &pi);
+
+ /**
+ * Here, we successfully setting up vcpu affinity in
+ * IOMMU guest mode. Now, we need to store the posted
+ * interrupt information in a per-vcpu ir_list so that
+ * we can reference to them directly when we update vcpu
+ * scheduling information in IOMMU irte.
+ */
+ if (!ret && pi.is_guest_mode)
+ svm_ir_list_add(svm, &pi);
+ } else {
+ /* Use legacy mode in IRTE */
+ struct amd_iommu_pi_data pi;
+
+ /**
+ * Here, pi is used to:
+ * - Tell IOMMU to use legacy mode for this interrupt.
+ * - Retrieve ga_tag of prior interrupt remapping data.
+ */
+ pi.is_guest_mode = false;
+ ret = irq_set_vcpu_affinity(host_irq, &pi);
+
+ /**
+ * Check if the posted interrupt was previously
+ * setup with the guest_mode by checking if the ga_tag
+ * was cached. If so, we need to clean up the per-vcpu
+ * ir_list.
+ */
+ if (!ret && pi.prev_ga_tag) {
+ int id = AVIC_GATAG_TO_VCPUID(pi.prev_ga_tag);
+ struct kvm_vcpu *vcpu;
+
+ vcpu = kvm_get_vcpu_by_id(kvm, id);
+ if (vcpu)
+ svm_ir_list_del(to_svm(vcpu), &pi);
+ }
+ }
+
+ if (!ret && svm) {
+ trace_kvm_pi_irte_update(svm->vcpu.vcpu_id,
+ host_irq, e->gsi,
+ vcpu_info.vector,
+ vcpu_info.pi_desc_addr, set);
+ }
+
+ 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);
@@ -5189,6 +5435,7 @@ 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)