[PATCH for-5.0 2/8] xive: Link "xive" property to XiveSource::xive pointer

[Greg Kurz]

The source object has both a pointer and a "xive" property pointing to the
notifier object. Confusing bugs could arise if these ever go out of sync.

Change the property definition so that it explicitely sets the pointer.
The property isn't optional : not being able to set the link is a bug
and QEMU should rather abort than exit in this case.

Signed-off-by: Greg Kurz <address@hidden>
---
 hw/intc/pnv_xive.c   |    4 ++--
 hw/intc/spapr_xive.c |    4 ++--
 hw/intc/xive.c       |   20 ++++++++++----------
 hw/ppc/pnv_psi.c     |    3 +--
 4 files changed, 15 insertions(+), 16 deletions(-)

diff --git a/hw/intc/pnv_xive.c b/hw/intc/pnv_xive.c
index 348f2fdd263d..9e23dc705dc3 100644
--- a/hw/intc/pnv_xive.c
+++ b/hw/intc/pnv_xive.c
@@ -1695,8 +1695,8 @@ static void pnv_xive_realize(DeviceState *dev, Error 
**errp)
      */
     object_property_set_int(OBJECT(xsrc), PNV_XIVE_NR_IRQS, "nr-irqs",
                             &error_fatal);
-    object_property_add_const_link(OBJECT(xsrc), "xive", OBJECT(xive),
-                                   &error_fatal);
+    object_property_set_link(OBJECT(xsrc), OBJECT(xive), "xive",
+                             &error_abort);
     object_property_set_bool(OBJECT(xsrc), true, "realized", &local_err);
     if (local_err) {
         error_propagate(errp, local_err);
diff --git a/hw/intc/spapr_xive.c b/hw/intc/spapr_xive.c
index 9cb8d38a3bab..10890aeeeb5b 100644
--- a/hw/intc/spapr_xive.c
+++ b/hw/intc/spapr_xive.c
@@ -276,8 +276,8 @@ static void spapr_xive_realize(DeviceState *dev, Error 
**errp)
      */
     object_property_set_int(OBJECT(xsrc), xive->nr_irqs, "nr-irqs",
                             &error_fatal);
-    object_property_add_const_link(OBJECT(xsrc), "xive", OBJECT(xive),
-                                   &error_fatal);
+    object_property_set_link(OBJECT(xsrc), OBJECT(xive), "xive",
+                             &error_abort);
     object_property_set_bool(OBJECT(xsrc), true, "realized", &local_err);
     if (local_err) {
         error_propagate(errp, local_err);
diff --git a/hw/intc/xive.c b/hw/intc/xive.c
index 5363fcaa416c..b69bceb4d255 100644
--- a/hw/intc/xive.c
+++ b/hw/intc/xive.c
@@ -1063,17 +1063,8 @@ static void xive_source_reset(void *dev)
 static void xive_source_realize(DeviceState *dev, Error **errp)
 {
     XiveSource *xsrc = XIVE_SOURCE(dev);
-    Object *obj;
-    Error *local_err = NULL;
-
-    obj = object_property_get_link(OBJECT(dev), "xive", &local_err);
-    if (!obj) {
-        error_propagate(errp, local_err);
-        error_prepend(errp, "required link 'xive' not found: ");
-        return;
-    }
 
-    xsrc->xive = XIVE_NOTIFIER(obj);
+    assert(xsrc->xive);
 
     if (!xsrc->nr_irqs) {
         error_setg(errp, "Number of interrupt needs to be greater than 0");
@@ -1122,6 +1113,14 @@ static Property xive_source_properties[] = {
     DEFINE_PROP_END_OF_LIST(),
 };
 
+static void xive_source_instance_init(Object *obj)
+{
+    object_property_add_link(obj, "xive", TYPE_XIVE_NOTIFIER,
+                             (Object **) &XIVE_SOURCE(obj)->xive,
+                             qdev_prop_allow_set_link_before_realize,
+                             OBJ_PROP_LINK_STRONG, &error_abort);
+}
+
 static void xive_source_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
@@ -1141,6 +1140,7 @@ static const TypeInfo xive_source_info = {
     .name          = TYPE_XIVE_SOURCE,
     .parent        = TYPE_DEVICE,
     .instance_size = sizeof(XiveSource),
+    .instance_init = xive_source_instance_init,
     .class_init    = xive_source_class_init,
 };
 
diff --git a/hw/ppc/pnv_psi.c b/hw/ppc/pnv_psi.c
index 68d0dfacfe2b..a360515a86f8 100644
--- a/hw/ppc/pnv_psi.c
+++ b/hw/ppc/pnv_psi.c
@@ -851,8 +851,7 @@ static void pnv_psi_power9_realize(DeviceState *dev, Error 
**errp)
                             &error_fatal);
     object_property_set_int(OBJECT(xsrc), PSIHB9_NUM_IRQS, "nr-irqs",
                             &error_fatal);
-    object_property_add_const_link(OBJECT(xsrc), "xive", OBJECT(psi),
-                                   &error_fatal);
+    object_property_set_link(OBJECT(xsrc), OBJECT(psi), "xive", &error_abort);
     object_property_set_bool(OBJECT(xsrc), true, "realized", &local_err);
     if (local_err) {
         error_propagate(errp, local_err);