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Diffstat (limited to 'hw/intc/arm_gicv3_its_kvm.c')
-rw-r--r--hw/intc/arm_gicv3_its_kvm.c131
1 files changed, 118 insertions, 13 deletions
diff --git a/hw/intc/arm_gicv3_its_kvm.c b/hw/intc/arm_gicv3_its_kvm.c
index a0441d6bd1..1f8991b8a6 100644
--- a/hw/intc/arm_gicv3_its_kvm.c
+++ b/hw/intc/arm_gicv3_its_kvm.c
@@ -53,23 +53,38 @@ static int kvm_its_send_msi(GICv3ITSState *s, uint32_t value, uint16_t devid)
     return kvm_vm_ioctl(kvm_state, KVM_SIGNAL_MSI, &msi);
 }
 
-static void kvm_arm_its_realize(DeviceState *dev, Error **errp)
+/**
+ * vm_change_state_handler - VM change state callback aiming at flushing
+ * ITS tables into guest RAM
+ *
+ * The tables get flushed to guest RAM whenever the VM gets stopped.
+ */
+static void vm_change_state_handler(void *opaque, int running,
+                                    RunState state)
 {
-    GICv3ITSState *s = ARM_GICV3_ITS_COMMON(dev);
-    Error *local_err = NULL;
+    GICv3ITSState *s = (GICv3ITSState *)opaque;
+    Error *err = NULL;
+    int ret;
 
-    /*
-     * Block migration of a KVM GICv3 ITS device: the API for saving and
-     * restoring the state in the kernel is not yet available
-     */
-    error_setg(&s->migration_blocker, "vITS migration is not implemented");
-    migrate_add_blocker(s->migration_blocker, &local_err);
-    if (local_err) {
-        error_propagate(errp, local_err);
-        error_free(s->migration_blocker);
+    if (running) {
         return;
     }
 
+    ret = kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_CTRL,
+                            KVM_DEV_ARM_ITS_SAVE_TABLES, NULL, true, &err);
+    if (err) {
+        error_report_err(err);
+    }
+    if (ret < 0 && ret != -EFAULT) {
+        abort();
+    }
+}
+
+static void kvm_arm_its_realize(DeviceState *dev, Error **errp)
+{
+    GICv3ITSState *s = ARM_GICV3_ITS_COMMON(dev);
+    Error *local_err = NULL;
+
     s->dev_fd = kvm_create_device(kvm_state, KVM_DEV_TYPE_ARM_VGIC_ITS, false);
     if (s->dev_fd < 0) {
         error_setg_errno(errp, -s->dev_fd, "error creating in-kernel ITS");
@@ -78,7 +93,7 @@ static void kvm_arm_its_realize(DeviceState *dev, Error **errp)
 
     /* explicit init of the ITS */
     kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_CTRL,
-                      KVM_DEV_ARM_VGIC_CTRL_INIT, NULL, true);
+                      KVM_DEV_ARM_VGIC_CTRL_INIT, NULL, true, &error_abort);
 
     /* register the base address */
     kvm_arm_register_device(&s->iomem_its_cntrl, -1, KVM_DEV_ARM_VGIC_GRP_ADDR,
@@ -86,9 +101,23 @@ static void kvm_arm_its_realize(DeviceState *dev, Error **errp)
 
     gicv3_its_init_mmio(s, NULL);
 
+    if (!kvm_device_check_attr(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
+        GITS_CTLR)) {
+        error_setg(&s->migration_blocker, "This operating system kernel "
+                   "does not support vITS migration");
+        migrate_add_blocker(s->migration_blocker, &local_err);
+        if (local_err) {
+            error_propagate(errp, local_err);
+            error_free(s->migration_blocker);
+            return;
+        }
+    }
+
     kvm_msi_use_devid = true;
     kvm_gsi_direct_mapping = false;
     kvm_msi_via_irqfd_allowed = kvm_irqfds_enabled();
+
+    qemu_add_vm_change_state_handler(vm_change_state_handler, s);
 }
 
 static void kvm_arm_its_init(Object *obj)
@@ -102,6 +131,80 @@ static void kvm_arm_its_init(Object *obj)
                              &error_abort);
 }
 
+/**
+ * kvm_arm_its_pre_save - handles the saving of ITS registers.
+ * ITS tables are flushed into guest RAM separately and earlier,
+ * through the VM change state handler, since at the moment pre_save()
+ * is called, the guest RAM has already been saved.
+ */
+static void kvm_arm_its_pre_save(GICv3ITSState *s)
+{
+    int i;
+
+    for (i = 0; i < 8; i++) {
+        kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
+                          GITS_BASER + i * 8, &s->baser[i], false,
+                          &error_abort);
+    }
+
+    kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
+                      GITS_CTLR, &s->ctlr, false, &error_abort);
+
+    kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
+                      GITS_CBASER, &s->cbaser, false, &error_abort);
+
+    kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
+                      GITS_CREADR, &s->creadr, false, &error_abort);
+
+    kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
+                      GITS_CWRITER, &s->cwriter, false, &error_abort);
+
+    kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
+                      GITS_IIDR, &s->iidr, false, &error_abort);
+}
+
+/**
+ * kvm_arm_its_post_load - Restore both the ITS registers and tables
+ */
+static void kvm_arm_its_post_load(GICv3ITSState *s)
+{
+    int i;
+
+    if (!s->iidr) {
+        return;
+    }
+
+    kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
+                      GITS_IIDR, &s->iidr, true, &error_abort);
+
+    /*
+     * must be written before GITS_CREADR since GITS_CBASER write
+     * access resets GITS_CREADR.
+     */
+    kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
+                      GITS_CBASER, &s->cbaser, true, &error_abort);
+
+    kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
+                      GITS_CREADR, &s->creadr, true, &error_abort);
+
+    kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
+                      GITS_CWRITER, &s->cwriter, true, &error_abort);
+
+
+    for (i = 0; i < 8; i++) {
+        kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
+                          GITS_BASER + i * 8, &s->baser[i], true,
+                          &error_abort);
+    }
+
+    kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_CTRL,
+                      KVM_DEV_ARM_ITS_RESTORE_TABLES, NULL, true,
+                      &error_abort);
+
+    kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_ITS_REGS,
+                      GITS_CTLR, &s->ctlr, true, &error_abort);
+}
+
 static void kvm_arm_its_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
@@ -109,6 +212,8 @@ static void kvm_arm_its_class_init(ObjectClass *klass, void *data)
 
     dc->realize = kvm_arm_its_realize;
     icc->send_msi = kvm_its_send_msi;
+    icc->pre_save = kvm_arm_its_pre_save;
+    icc->post_load = kvm_arm_its_post_load;
 }
 
 static const TypeInfo kvm_arm_its_info = {