5 files changed, 49 insertions, 0 deletions

diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h
index f3f0ffd5fb..db75c6dfd0 100644
--- a/include/hw/pci/pci.h
+++ b/include/hw/pci/pci.h
@@ -265,6 +265,7 @@ typedef struct PCIReqIDCache PCIReqIDCache;
 
 struct PCIDevice {
     DeviceState qdev;
+    bool partially_hotplugged;
 
     /* PCI config space */
     uint8_t *config;
@@ -352,6 +353,9 @@ struct PCIDevice {
     MSIVectorUseNotifier msix_vector_use_notifier;
     MSIVectorReleaseNotifier msix_vector_release_notifier;
     MSIVectorPollNotifier msix_vector_poll_notifier;
+
+    /* ID of standby device in net_failover pair */
+    char *failover_pair_id;
 };
 
 void pci_register_bar(PCIDevice *pci_dev, int region_num,
diff --git a/include/hw/qdev-core.h b/include/hw/qdev-core.h
index aa123f88cb..1518495b1e 100644
--- a/include/hw/qdev-core.h
+++ b/include/hw/qdev-core.h
@@ -78,6 +78,19 @@ typedef void (*BusUnrealize)(BusState *bus, Error **errp);
  * respective parent types.
  *   </para>
  * </note>
+ *
+ * # Hiding a device #
+ * To hide a device, a DeviceListener function should_be_hidden() needs to
+ * be registered.
+ * It can be used to defer adding a device and therefore hide it from the
+ * guest. The handler registering to this DeviceListener can save the QOpts
+ * passed to it for re-using it later and must return that it wants the device
+ * to be/remain hidden or not. When the handler function decides the device
+ * shall not be hidden it will be added in qdev_device_add() and
+ * realized as any other device. Otherwise qdev_device_add() will return early
+ * without adding the device. The guest will not see a "hidden" device
+ * until it was marked don't hide and qdev_device_add called again.
+ *
  */
 typedef struct DeviceClass {
     /*< private >*/
@@ -143,6 +156,7 @@ struct DeviceState {
     bool pending_deleted_event;
     QemuOpts *opts;
     int hotplugged;
+    bool allow_unplug_during_migration;
     BusState *parent_bus;
     QLIST_HEAD(, NamedGPIOList) gpios;
     QLIST_HEAD(, BusState) child_bus;
@@ -154,6 +168,12 @@ struct DeviceState {
 struct DeviceListener {
     void (*realize)(DeviceListener *listener, DeviceState *dev);
     void (*unrealize)(DeviceListener *listener, DeviceState *dev);
+    /*
+     * This callback is called upon init of the DeviceState and allows to
+     * inform qdev that a device should be hidden, depending on the device
+     * opts, for example, to hide a standby device.
+     */
+    int (*should_be_hidden)(DeviceListener *listener, QemuOpts *device_opts);
     QTAILQ_ENTRY(DeviceListener) link;
 };
 
@@ -451,4 +471,14 @@ static inline bool qbus_is_hotpluggable(BusState *bus)
 void device_listener_register(DeviceListener *listener);
 void device_listener_unregister(DeviceListener *listener);
 
+/**
+ * @qdev_should_hide_device:
+ * @opts: QemuOpts as passed on cmdline.
+ *
+ * Check if a device should be added.
+ * When a device is added via qdev_device_add() this will be called,
+ * and return if the device should be added now or not.
+ */
+bool qdev_should_hide_device(QemuOpts *opts);
+
 #endif
diff --git a/include/hw/virtio/virtio-net.h b/include/hw/virtio/virtio-net.h
index 07a9319f4b..96c68d4a92 100644
--- a/include/hw/virtio/virtio-net.h
+++ b/include/hw/virtio/virtio-net.h
@@ -18,6 +18,7 @@
 #include "standard-headers/linux/virtio_net.h"
 #include "hw/virtio/virtio.h"
 #include "net/announce.h"
+#include "qemu/option_int.h"
 
 #define TYPE_VIRTIO_NET "virtio-net-device"
 #define VIRTIO_NET(obj) \
@@ -43,6 +44,7 @@ typedef struct virtio_net_conf
     int32_t speed;
     char *duplex_str;
     uint8_t duplex;
+    char *primary_id_str;
 } virtio_net_conf;
 
 /* Coalesced packets type & status */
@@ -187,6 +189,16 @@ struct VirtIONet {
     AnnounceTimer announce_timer;
     bool needs_vnet_hdr_swap;
     bool mtu_bypass_backend;
+    QemuOpts *primary_device_opts;
+    QDict *primary_device_dict;
+    DeviceState *primary_dev;
+    BusState *primary_bus;
+    char *primary_device_id;
+    char *standby_id;
+    bool primary_should_be_hidden;
+    bool failover;
+    DeviceListener primary_listener;
+    Notifier migration_state;
 };
 
 void virtio_net_set_netclient_name(VirtIONet *n, const char *name,
diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h
index 60bbc0e18a..3448d67d2a 100644
--- a/include/hw/virtio/virtio.h
+++ b/include/hw/virtio/virtio.h
@@ -160,6 +160,7 @@ typedef struct VirtioDeviceClass {
      */
     int (*post_load)(VirtIODevice *vdev);
     const VMStateDescription *vmsd;
+    bool (*primary_unplug_pending)(void *opaque);
 } VirtioDeviceClass;
 
 void virtio_instance_init_common(Object *proxy_obj, void *data,
diff --git a/include/migration/vmstate.h b/include/migration/vmstate.h
index b9ee563aa4..ac4f46a67d 100644
--- a/include/migration/vmstate.h
+++ b/include/migration/vmstate.h
@@ -186,6 +186,8 @@ struct VMStateDescription {
     int (*pre_save)(void *opaque);
     int (*post_save)(void *opaque);
     bool (*needed)(void *opaque);
+    bool (*dev_unplug_pending)(void *opaque);
+
     const VMStateField *fields;
     const VMStateDescription **subsections;
 };