QOM/QTest infrastructure fixes

* QOM machine memory and build fixes
 * QOM link<> and child<> property reference counting fixes
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2.0.22 (GNU/Linux)
 
 iQIcBAABAgAGBQJTKg+kAAoJEPou0S0+fgE/VoIP/0V9g3IzNHnLCmEUeS1TIy1T
 aCbjB1vzVu1cZPtV/afvD6WmhQivODlS82pioS93FxU0E52zx4U+roN1w81mer6R
 9+ylYL27bH6I0VAyE68wD+C2HDZCgYSwZ2LPsOk9V1xlHad4cfmtrB+KEyd6dMdf
 II4FNyo3aYRodLbA/gWR0ZI86oVaS0HtZtZMI2OANpT+aKZYWDMnrDdEGKo92PEU
 QGKI6esmGEbm5DkKpHpUjjus8ml6AbfnFsT8adKnhw+t//IiZhAyfMadgySZ6yPO
 35FRx/qHEoTiIDgbR4Nmhn4qJCXtyzufWT+jI9ARZ1SSrwRWX7uZQoaDW0J++5c+
 8W0mzhy0+9B0CwOnK31DcKqDSE6WAF8c8MYqwCC9fk6JlHmYsJh2Messw6ZxF2EP
 2Rg3CeCM4XK4V+E+dy2aQWaOAEQ3XUGifA/n4LGwhrOAM/KXTy5XJOuCbEqhd3gz
 CPELYNubEG8mncPE/6A1IxdaVk+4FSvlzrtRlRmLmJKypSXjZ2vcAgo9P0LyRgDf
 4mKuXTl1XgNYDtD+X2+5lrCCyZ23Z1L/kaPpZphlj3HrdAxvNWEYQZHMLTflMy1i
 HRAqxcZvwzz0ecZWTrpVBEnrgHR1YV5p+p/MdPG4w0+QplpGqPn+FQHOqrEYL+ub
 Q/A9y1c8CORaTx2P+OiP
 =+i1T
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/afaerber/tags/qom-devices-for-2.0' into staging

QOM/QTest infrastructure fixes

* QOM machine memory and build fixes
* QOM link<> and child<> property reference counting fixes

# gpg: Signature made Wed 19 Mar 2014 21:44:04 GMT using RSA key ID 3E7E013F
# gpg: Good signature from "Andreas Färber <afaerber@suse.de>"
# gpg:                 aka "Andreas Färber <afaerber@suse.com>"

* remotes/afaerber/tags/qom-devices-for-2.0:
  virtio-rng: Avoid default_backend refcount leak
  qom: Add check() argument to object_property_add_link()
  qom: Make QOM link property unref optional
  qom: Don't make link NULL on object_property_set_link() failure
  qom: Split object_property_set_link()
  vl.c: Fix OpenBSD compilation issue due to namespace collisions
  vl.c: Fix memory leak in qemu_register_machine()

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

hw/core/qdev-properties.c

@@ -21,6 +21,18 @@ void qdev_prop_set_after_realize(DeviceState *dev, const char *name,
     }
 }
 
+void qdev_prop_allow_set_link_before_realize(Object *obj, const char *name,
+                                             Object *val, Error **errp)
+{
+    DeviceState *dev = DEVICE(obj);
+
+    if (dev->realized) {
+        error_setg(errp, "Attempt to set link property '%s' on device '%s' "
+                   "(type '%s') after it was realized",
+                   name, dev->id, object_get_typename(obj));
+    }
+}
+
 void *qdev_get_prop_ptr(DeviceState *dev, Property *prop)
 {
     void *ptr = dev;

hw/core/qdev.c

@@ -98,6 +98,8 @@ static void bus_add_child(BusState *bus, DeviceState *child)
     object_property_add_link(OBJECT(bus), name,
                              object_get_typename(OBJECT(child)),
                              (Object **)&kid->child,
+                             NULL, /* read-only property */
+                             0, /* return ownership on prop deletion */
                              NULL);
 }
 
@@ -824,7 +826,8 @@ static void device_initfn(Object *obj)
     } while (class != object_class_by_name(TYPE_DEVICE));
 
     object_property_add_link(OBJECT(dev), "parent_bus", TYPE_BUS,
-                             (Object **)&dev->parent_bus, &error_abort);
+                             (Object **)&dev->parent_bus, NULL, 0,
+                             &error_abort);
 }
 
 static void device_post_init(Object *obj)
@@ -944,7 +947,10 @@ static void qbus_initfn(Object *obj)
     QTAILQ_INIT(&bus->children);
     object_property_add_link(obj, QDEV_HOTPLUG_HANDLER_PROPERTY,
                              TYPE_HOTPLUG_HANDLER,
-                             (Object **)&bus->hotplug_handler, NULL);
+                             (Object **)&bus->hotplug_handler,
+                             object_property_allow_set_link,
+                             OBJ_PROP_LINK_UNREF_ON_RELEASE,
+                             NULL);
     object_property_add_bool(obj, "realized",
                              bus_get_realized, bus_set_realized, NULL);
 }

hw/dma/xilinx_axidma.c

@@ -537,9 +537,15 @@ static void xilinx_axidma_realize(DeviceState *dev, Error **errp)
     Error *local_errp = NULL;
 
     object_property_add_link(OBJECT(ds), "dma", TYPE_XILINX_AXI_DMA,
-                             (Object **)&ds->dma, &local_errp);
+                             (Object **)&ds->dma,
+                             object_property_allow_set_link,
+                             OBJ_PROP_LINK_UNREF_ON_RELEASE,
+                             &local_errp);
     object_property_add_link(OBJECT(cs), "dma", TYPE_XILINX_AXI_DMA,
-                             (Object **)&cs->dma, &local_errp);
+                             (Object **)&cs->dma,
+                             object_property_allow_set_link,
+                             OBJ_PROP_LINK_UNREF_ON_RELEASE,
+                             &local_errp);
     if (local_errp) {
         goto xilinx_axidma_realize_fail;
     }
@@ -571,10 +577,16 @@ static void xilinx_axidma_init(Object *obj)
     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
 
     object_property_add_link(obj, "axistream-connected", TYPE_STREAM_SLAVE,
-                             (Object **)&s->tx_data_dev, &error_abort);
+                             (Object **)&s->tx_data_dev,
+                             qdev_prop_allow_set_link_before_realize,
+                             OBJ_PROP_LINK_UNREF_ON_RELEASE,
+                             &error_abort);
     object_property_add_link(obj, "axistream-control-connected",
                              TYPE_STREAM_SLAVE,
-                             (Object **)&s->tx_control_dev, &error_abort);
+                             (Object **)&s->tx_control_dev,
+                             qdev_prop_allow_set_link_before_realize,
+                             OBJ_PROP_LINK_UNREF_ON_RELEASE,
+                             &error_abort);
 
     object_initialize(&s->rx_data_dev, sizeof(s->rx_data_dev),
                       TYPE_XILINX_AXI_DMA_DATA_STREAM);

hw/net/xilinx_axienet.c

@@ -945,9 +945,15 @@ static void xilinx_enet_realize(DeviceState *dev, Error **errp)
     Error *local_errp = NULL;
 
     object_property_add_link(OBJECT(ds), "enet", "xlnx.axi-ethernet",
-                             (Object **) &ds->enet, &local_errp);
+                             (Object **) &ds->enet,
+                             object_property_allow_set_link,
+                             OBJ_PROP_LINK_UNREF_ON_RELEASE,
+                             &local_errp);
     object_property_add_link(OBJECT(cs), "enet", "xlnx.axi-ethernet",
-                             (Object **) &cs->enet, &local_errp);
+                             (Object **) &cs->enet,
+                             object_property_allow_set_link,
+                             OBJ_PROP_LINK_UNREF_ON_RELEASE,
+                             &local_errp);
     if (local_errp) {
         goto xilinx_enet_realize_fail;
     }
@@ -982,10 +988,16 @@ static void xilinx_enet_init(Object *obj)
     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
 
     object_property_add_link(obj, "axistream-connected", TYPE_STREAM_SLAVE,
-                             (Object **) &s->tx_data_dev, &error_abort);
+                             (Object **) &s->tx_data_dev,
+                             qdev_prop_allow_set_link_before_realize,
+                             OBJ_PROP_LINK_UNREF_ON_RELEASE,
+                             &error_abort);
     object_property_add_link(obj, "axistream-control-connected",
                              TYPE_STREAM_SLAVE,
-                             (Object **) &s->tx_control_dev, &error_abort);
+                             (Object **) &s->tx_control_dev,
+                             qdev_prop_allow_set_link_before_realize,
+                             OBJ_PROP_LINK_UNREF_ON_RELEASE,
+                             &error_abort);
 
     object_initialize(&s->rx_data_dev, sizeof(s->rx_data_dev),
                       TYPE_XILINX_AXI_ENET_DATA_STREAM);

hw/pcmcia/pxa2xx.c

@@ -198,7 +198,9 @@ static void pxa2xx_pcmcia_initfn(Object *obj)
     s->slot.irq = qemu_allocate_irqs(pxa2xx_pcmcia_set_irq, s, 1)[0];
 
     object_property_add_link(obj, "card", TYPE_PCMCIA_CARD,
-                             (Object **)&s->card, NULL);
+                             (Object **)&s->card,
+                             NULL, /* read-only property */
+                             0, NULL);
 }
 
 /* Insert a new card into a slot */

hw/s390x/s390-virtio-bus.c

@@ -313,7 +313,9 @@ static void s390_virtio_rng_instance_init(Object *obj)
     object_initialize(&dev->vdev, sizeof(dev->vdev), TYPE_VIRTIO_RNG);
     object_property_add_child(obj, "virtio-backend", OBJECT(&dev->vdev), NULL);
     object_property_add_link(obj, "rng", TYPE_RNG_BACKEND,
-                             (Object **)&dev->vdev.conf.rng, NULL);
+                             (Object **)&dev->vdev.conf.rng,
+                             qdev_prop_allow_set_link_before_realize,
+                             OBJ_PROP_LINK_UNREF_ON_RELEASE, NULL);
 }
 
 static uint64_t s390_virtio_device_vq_token(VirtIOS390Device *dev, int vq)

hw/s390x/virtio-ccw.c

@@ -1272,7 +1272,9 @@ static void virtio_ccw_rng_instance_init(Object *obj)
     object_initialize(&dev->vdev, sizeof(dev->vdev), TYPE_VIRTIO_RNG);
     object_property_add_child(obj, "virtio-backend", OBJECT(&dev->vdev), NULL);
     object_property_add_link(obj, "rng", TYPE_RNG_BACKEND,
-                             (Object **)&dev->vdev.conf.rng, NULL);
+                             (Object **)&dev->vdev.conf.rng,
+                             qdev_prop_allow_set_link_before_realize,
+                             OBJ_PROP_LINK_UNREF_ON_RELEASE, NULL);
 }
 
 static Property virtio_ccw_rng_properties[] = {

hw/virtio/virtio-pci.c

@@ -1517,7 +1517,9 @@ static void virtio_rng_initfn(Object *obj)
     object_initialize(&dev->vdev, sizeof(dev->vdev), TYPE_VIRTIO_RNG);
     object_property_add_child(obj, "virtio-backend", OBJECT(&dev->vdev), NULL);
     object_property_add_link(obj, "rng", TYPE_RNG_BACKEND,
-                             (Object **)&dev->vdev.conf.rng, NULL);
+                             (Object **)&dev->vdev.conf.rng,
+                             qdev_prop_allow_set_link_before_realize,
+                             OBJ_PROP_LINK_UNREF_ON_RELEASE, NULL);
 
 }
 

hw/virtio/virtio-rng.c

@@ -162,6 +162,9 @@ static void virtio_rng_device_realize(DeviceState *dev, Error **errp)
                                   OBJECT(vrng->conf.default_backend),
                                   NULL);
 
+        /* The child property took a reference, we can safely drop ours now */
+        object_unref(OBJECT(vrng->conf.default_backend));
+
         object_property_set_link(OBJECT(dev),
                                  OBJECT(vrng->conf.default_backend),
                                  "rng", NULL);
@@ -223,7 +226,9 @@ static void virtio_rng_initfn(Object *obj)
     VirtIORNG *vrng = VIRTIO_RNG(obj);
 
     object_property_add_link(obj, "rng", TYPE_RNG_BACKEND,
-                             (Object **)&vrng->conf.rng, NULL);
+                             (Object **)&vrng->conf.rng,
+                             qdev_prop_allow_set_link_before_realize,
+                             OBJ_PROP_LINK_UNREF_ON_RELEASE, NULL);
 }
 
 static const TypeInfo virtio_rng_info = {

include/hw/boards.h

@@ -54,6 +54,7 @@ struct QEMUMachine {
 int qemu_register_machine(QEMUMachine *m);
 
 #define TYPE_MACHINE "machine"
+#undef MACHINE  /* BSD defines it and QEMU does not use it */
 #define MACHINE(obj) \
     OBJECT_CHECK(MachineState, (obj), TYPE_MACHINE)
 #define MACHINE_GET_CLASS(obj) \

include/hw/qdev-properties.h

@@ -204,4 +204,15 @@ void qdev_property_add_static(DeviceState *dev, Property *prop, Error **errp);
  */
 void qdev_prop_set_after_realize(DeviceState *dev, const char *name,
                                  Error **errp);
+
+/**
+ * qdev_prop_allow_set_link_before_realize:
+ *
+ * Set the #Error object if an attempt is made to set the link after realize.
+ * This function should be used as the check() argument to
+ * object_property_add_link().
+ */
+void qdev_prop_allow_set_link_before_realize(Object *obj, const char *name,
+                                             Object *val, Error **errp);
+
 #endif

include/qom/object.h

@@ -1067,12 +1067,29 @@ Object *object_resolve_path_component(Object *parent, const gchar *part);
 void object_property_add_child(Object *obj, const char *name,
                                Object *child, Error **errp);
 
+typedef enum {
+    /* Unref the link pointer when the property is deleted */
+    OBJ_PROP_LINK_UNREF_ON_RELEASE = 0x1,
+} ObjectPropertyLinkFlags;
+
+/**
+ * object_property_allow_set_link:
+ *
+ * The default implementation of the object_property_add_link() check()
+ * callback function.  It allows the link property to be set and never returns
+ * an error.
+ */
+void object_property_allow_set_link(Object *, const char *,
+                                    Object *, Error **);
+
 /**
  * object_property_add_link:
  * @obj: the object to add a property to
  * @name: the name of the property
  * @type: the qobj type of the link
  * @child: a pointer to where the link object reference is stored
+ * @check: callback to veto setting or NULL if the property is read-only
+ * @flags: additional options for the link
  * @errp: if an error occurs, a pointer to an area to store the area
  *
  * Links establish relationships between objects.  Links are unidirectional
@@ -1081,13 +1098,23 @@ void object_property_add_child(Object *obj, const char *name,
  *
  * Links form the graph in the object model.
  *
+ * The <code>@check()</code> callback is invoked when
+ * object_property_set_link() is called and can raise an error to prevent the
+ * link being set.  If <code>@check</code> is NULL, the property is read-only
+ * and cannot be set.
+ *
  * Ownership of the pointer that @child points to is transferred to the
  * link property.  The reference count for <code>*@child</code> is
  * managed by the property from after the function returns till the
- * property is deleted with object_property_del().
+ * property is deleted with object_property_del().  If the
+ * <code>@flags</code> <code>OBJ_PROP_LINK_UNREF_ON_RELEASE</code> bit is set,
+ * the reference count is decremented when the property is deleted.
  */
 void object_property_add_link(Object *obj, const char *name,
                               const char *type, Object **child,
+                              void (*check)(Object *obj, const char *name,
+                                            Object *val, Error **errp),
+                              ObjectPropertyLinkFlags flags,
                               Error **errp);
 
 /**

qom/object.c

@@ -1023,10 +1023,23 @@ out:
     g_free(type);
 }
 
+void object_property_allow_set_link(Object *obj, const char *name,
+                                    Object *val, Error **errp)
+{
+    /* Allow the link to be set, always */
+}
+
+typedef struct {
+    Object **child;
+    void (*check)(Object *, const char *, Object *, Error **);
+    ObjectPropertyLinkFlags flags;
+} LinkProperty;
+
 static void object_get_link_property(Object *obj, Visitor *v, void *opaque,
                                      const char *name, Error **errp)
 {
-    Object **child = opaque;
+    LinkProperty *lprop = opaque;
+    Object **child = lprop->child;
     gchar *path;
 
     if (*child) {
@@ -1039,65 +1052,119 @@ static void object_get_link_property(Object *obj, Visitor *v, void *opaque,
     }
 }
 
+/*
+ * object_resolve_link:
+ *
+ * Lookup an object and ensure its type matches the link property type.  This
+ * is similar to object_resolve_path() except type verification against the
+ * link property is performed.
+ *
+ * Returns: The matched object or NULL on path lookup failures.
+ */
+static Object *object_resolve_link(Object *obj, const char *name,
+                                   const char *path, Error **errp)
+{
+    const char *type;
+    gchar *target_type;
+    bool ambiguous = false;
+    Object *target;
+
+    /* Go from link<FOO> to FOO.  */
+    type = object_property_get_type(obj, name, NULL);
+    target_type = g_strndup(&type[5], strlen(type) - 6);
+    target = object_resolve_path_type(path, target_type, &ambiguous);
+
+    if (ambiguous) {
+        error_set(errp, QERR_AMBIGUOUS_PATH, path);
+    } else if (!target) {
+        target = object_resolve_path(path, &ambiguous);
+        if (target || ambiguous) {
+            error_set(errp, QERR_INVALID_PARAMETER_TYPE, name, target_type);
+        } else {
+            error_set(errp, QERR_DEVICE_NOT_FOUND, path);
+        }
+        target = NULL;
+    }
+    g_free(target_type);
+
+    return target;
+}
+
 static void object_set_link_property(Object *obj, Visitor *v, void *opaque,
                                      const char *name, Error **errp)
 {
-    Object **child = opaque;
-    Object *old_target;
-    bool ambiguous = false;
-    const char *type;
-    char *path;
-    gchar *target_type;
+    Error *local_err = NULL;
+    LinkProperty *prop = opaque;
+    Object **child = prop->child;
+    Object *old_target = *child;
+    Object *new_target = NULL;
+    char *path = NULL;
 
-    type = object_property_get_type(obj, name, NULL);
+    visit_type_str(v, &path, name, &local_err);
 
-    visit_type_str(v, &path, name, errp);
-
-    old_target = *child;
-    *child = NULL;
-
-    if (strcmp(path, "") != 0) {
-        Object *target;
-
-        /* Go from link<FOO> to FOO.  */
-        target_type = g_strndup(&type[5], strlen(type) - 6);
-        target = object_resolve_path_type(path, target_type, &ambiguous);
-
-        if (ambiguous) {
-            error_set(errp, QERR_AMBIGUOUS_PATH, path);
-        } else if (target) {
-            object_ref(target);
-            *child = target;
-        } else {
-            target = object_resolve_path(path, &ambiguous);
-            if (target || ambiguous) {
-                error_set(errp, QERR_INVALID_PARAMETER_TYPE, name, target_type);
-            } else {
-                error_set(errp, QERR_DEVICE_NOT_FOUND, path);
-            }
-        }
-        g_free(target_type);
+    if (!local_err && strcmp(path, "") != 0) {
+        new_target = object_resolve_link(obj, name, path, &local_err);
     }
 
     g_free(path);
+    if (local_err) {
+        error_propagate(errp, local_err);
+        return;
+    }
 
+    prop->check(obj, name, new_target, &local_err);
+    if (local_err) {
+        error_propagate(errp, local_err);
+        return;
+    }
+
+    if (new_target) {
+        object_ref(new_target);
+    }
+    *child = new_target;
     if (old_target != NULL) {
         object_unref(old_target);
     }
 }
 
+static void object_release_link_property(Object *obj, const char *name,
+                                         void *opaque)
+{
+    LinkProperty *prop = opaque;
+
+    if ((prop->flags & OBJ_PROP_LINK_UNREF_ON_RELEASE) && *prop->child) {
+        object_unref(*prop->child);
+    }
+    g_free(prop);
+}
+
 void object_property_add_link(Object *obj, const char *name,
                               const char *type, Object **child,
+                              void (*check)(Object *, const char *,
+                                            Object *, Error **),
+                              ObjectPropertyLinkFlags flags,
                               Error **errp)
 {
+    Error *local_err = NULL;
+    LinkProperty *prop = g_malloc(sizeof(*prop));
     gchar *full_type;
 
+    prop->child = child;
+    prop->check = check;
+    prop->flags = flags;
+
     full_type = g_strdup_printf("link<%s>", type);
 
     object_property_add(obj, name, full_type,
                         object_get_link_property,
-                        object_set_link_property,
-                        NULL, child, errp);
+                        check ? object_set_link_property : NULL,
+                        object_release_link_property,
+                        prop,
+                        &local_err);
+    if (local_err) {
+        error_propagate(errp, local_err);
+        g_free(prop);
+    }
 
     g_free(full_type);
 }

ui/console.c

@@ -1180,7 +1180,10 @@ static QemuConsole *new_console(DisplayState *ds, console_type_t console_type)
     obj = object_new(TYPE_QEMU_CONSOLE);
     s = QEMU_CONSOLE(obj);
     object_property_add_link(obj, "device", TYPE_DEVICE,
-                             (Object **)&s->device, &local_err);
+                             (Object **)&s->device,
+                             object_property_allow_set_link,
+                             OBJ_PROP_LINK_UNREF_ON_RELEASE,
+                             &local_err);
     object_property_add_uint32_ptr(obj, "head",
                                    &s->head, &local_err);
 

vl.c

@@ -58,6 +58,7 @@ int main(int argc, char **argv)
 
 #include <glib.h>
 
+#include "qemu/sockets.h"
 #include "hw/hw.h"
 #include "hw/boards.h"
 #include "hw/usb.h"
@@ -103,7 +104,6 @@ int main(int argc, char **argv)
 
 #include "disas/disas.h"
 
-#include "qemu/sockets.h"
 
 #include "slirp/libslirp.h"
 
@@ -1587,14 +1587,16 @@ static void machine_class_init(ObjectClass *oc, void *data)
 
 int qemu_register_machine(QEMUMachine *m)
 {
+    char *name = g_strconcat(m->name, TYPE_MACHINE_SUFFIX, NULL);
     TypeInfo ti = {
-        .name       = g_strconcat(m->name, TYPE_MACHINE_SUFFIX, NULL),
+        .name       = name,
         .parent     = TYPE_MACHINE,
         .class_init = machine_class_init,
         .class_data = (void *)m,
     };
 
     type_register(&ti);
+    g_free(name);
 
     return 0;
 }