qdev: add to BusState "hotplug-handler" link

It will allow to reuse field with different BUSes,
reducing code duplication. Field is intended for
replacing 'hotplug_qdev' field in PCIBus and also
will allow to avoid adding equivalent field to
DimmBus with possiblitity to refactor other BUSes
to use it instead of custom field.
In addition once all users of allow_hotplug field
are converted to new API, link could replace
allow_hotplug field in qdev hotplug code.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/include/hw/qdev-core.h b/include/hw/qdev-core.h
index 2c4f140..41ec533 100644
--- a/include/hw/qdev-core.h
+++ b/include/hw/qdev-core.h
@@ -8,6 +8,7 @@
 #include "qom/object.h"
 #include "hw/irq.h"
 #include "qapi/error.h"
+#include "hw/hotplug.h"
 
 enum {
     DEV_NVECTORS_UNSPECIFIED = -1,
@@ -180,14 +181,18 @@ typedef struct BusChild {
     QTAILQ_ENTRY(BusChild) sibling;
 } BusChild;
 
+#define QDEV_HOTPLUG_HANDLER_PROPERTY "hotplug-handler"
+
 /**
  * BusState:
+ * @hotplug_device: link to a hotplug device associated with bus.
  */
 struct BusState {
     Object obj;
     DeviceState *parent;
     const char *name;
     int allow_hotplug;
+    HotplugHandler *hotplug_handler;
     int max_index;
     QTAILQ_HEAD(ChildrenHead, BusChild) children;
     QLIST_ENTRY(BusState) sibling;
@@ -321,4 +326,11 @@ extern int qdev_hotplug;
 
 char *qdev_get_dev_path(DeviceState *dev);
 
+static inline void qbus_set_hotplug_handler(BusState *bus, DeviceState *handler,
+                                            Error **errp)
+{
+    object_property_set_link(OBJECT(bus), OBJECT(handler),
+                             QDEV_HOTPLUG_HANDLER_PROPERTY, errp);
+    bus->allow_hotplug = 1;
+}
 #endif