@@ -680,6 +680,7 @@ struct kvm_ppc_cpu_char {
/* POWER9 XIVE Native Interrupt Controller */
#define KVM_DEV_XIVE_GRP_CTRL 1
#define KVM_DEV_XIVE_RESET 1
+#define KVM_DEV_XIVE_EQ_SYNC 2
#define KVM_DEV_XIVE_GRP_SOURCE 2 /* 64-bit source identifier */
#define KVM_DEV_XIVE_GRP_SOURCE_CONFIG 3 /* 64-bit source identifier */
#define KVM_DEV_XIVE_GRP_EQ_CONFIG 4 /* 64-bit EQ identifier */
@@ -681,6 +681,88 @@ static int kvmppc_xive_reset(struct kvmppc_xive *xive)
return 0;
}
+static void kvmppc_xive_native_sync_sources(struct kvmppc_xive_src_block *sb)
+{
+ int j;
+
+ for (j = 0; j < KVMPPC_XICS_IRQ_PER_ICS; j++) {
+ struct kvmppc_xive_irq_state *state = &sb->irq_state[j];
+ struct xive_irq_data *xd;
+ u32 hw_num;
+
+ if (!state->valid)
+ continue;
+
+ /*
+ * The struct kvmppc_xive_irq_state reflects the state
+ * of the EAS configuration and not the state of the
+ * source. The source is masked setting the PQ bits to
+ * '-Q', which is what is being done before calling
+ * the KVM_DEV_XIVE_EQ_SYNC control.
+ *
+ * If a source EAS is configured, OPAL syncs the XIVE
+ * IC of the source and the XIVE IC of the previous
+ * target if any.
+ *
+ * So it should be fine ignoring MASKED sources as
+ * they have been synced already.
+ */
+ if (state->act_priority == MASKED)
+ continue;
+
+ kvmppc_xive_select_irq(state, &hw_num, &xd);
+ xive_native_sync_source(hw_num);
+ xive_native_sync_queue(hw_num);
+ }
+}
+
+static int kvmppc_xive_native_vcpu_eq_sync(struct kvm_vcpu *vcpu)
+{
+ struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu;
+ unsigned int prio;
+
+ if (!xc)
+ return -ENOENT;
+
+ for (prio = 0; prio < KVMPPC_XIVE_Q_COUNT; prio++) {
+ struct xive_q *q = &xc->queues[prio];
+
+ if (!q->qpage)
+ continue;
+
+ /* Mark EQ page dirty for migration */
+ mark_page_dirty(vcpu->kvm, gpa_to_gfn(q->guest_qaddr));
+ }
+ return 0;
+}
+
+static int kvmppc_xive_native_eq_sync(struct kvmppc_xive *xive)
+{
+ struct kvm *kvm = xive->kvm;
+ struct kvm_vcpu *vcpu;
+ unsigned int i;
+
+ pr_devel("%s\n", __func__);
+
+ mutex_lock(&kvm->lock);
+ for (i = 0; i <= xive->max_sbid; i++) {
+ struct kvmppc_xive_src_block *sb = xive->src_blocks[i];
+
+ if (sb) {
+ arch_spin_lock(&sb->lock);
+ kvmppc_xive_native_sync_sources(sb);
+ arch_spin_unlock(&sb->lock);
+ }
+ }
+
+ kvm_for_each_vcpu(i, vcpu, kvm) {
+ kvmppc_xive_native_vcpu_eq_sync(vcpu);
+ }
+ mutex_unlock(&kvm->lock);
+
+ return 0;
+}
+
static int kvmppc_xive_native_set_attr(struct kvm_device *dev,
struct kvm_device_attr *attr)
{
@@ -691,6 +773,8 @@ static int kvmppc_xive_native_set_attr(struct kvm_device *dev,
switch (attr->attr) {
case KVM_DEV_XIVE_RESET:
return kvmppc_xive_reset(xive);
+ case KVM_DEV_XIVE_EQ_SYNC:
+ return kvmppc_xive_native_eq_sync(xive);
}
break;
case KVM_DEV_XIVE_GRP_SOURCE:
@@ -729,6 +813,7 @@ static int kvmppc_xive_native_has_attr(struct kvm_device *dev,
case KVM_DEV_XIVE_GRP_CTRL:
switch (attr->attr) {
case KVM_DEV_XIVE_RESET:
+ case KVM_DEV_XIVE_EQ_SYNC:
return 0;
}
break;
@@ -23,6 +23,12 @@ the legacy interrupt mode, referred as XICS (POWER7/8).
queues. To be used by kexec and kdump.
Errors: none
+ 1.2 KVM_DEV_XIVE_EQ_SYNC (write only)
+ Sync all the sources and queues and mark the EQ pages dirty. This
+ to make sure that a consistent memory state is captured when
+ migrating the VM.
+ Errors: none
+
2. KVM_DEV_XIVE_GRP_SOURCE (write only)
Initializes a new source in the XIVE device and mask it.
Attributes:
@@ -100,3 +106,26 @@ the legacy interrupt mode, referred as XICS (POWER7/8).
Errors:
-ENOENT: Unknown source number
-EINVAL: Not initialized source number
+
+* Migration:
+
+ Saving the state of a VM using the XIVE native exploitation mode
+ should follow a specific sequence. When the VM is stopped :
+
+ 1. Mask all sources (PQ=01) to stop the flow of events.
+
+ 2. Sync the XIVE device with the KVM control KVM_DEV_XIVE_EQ_SYNC to
+ flush any in-flight event notification and to stabilize the EQs. At
+ this stage, the EQ pages are marked dirty to make sure they are
+ transferred in the migration sequence.
+
+ 3. Capture the state of the source targeting, the EQs configuration
+ and the state of thread interrupt context registers.
+
+ Restore is similar :
+
+ 1. Restore the EQ configuration. As targeting depends on it.
+ 2. Restore targeting
+ 3. Restore the thread interrupt contexts
+ 4. Restore the source states
+ 5. Let the vCPU run