qdev: Drop misleading qdev_free() function

The qdev_free() function name is misleading since all the function does
is unlink the device from its parent.  The device is not necessarily
freed.

The device will be freed when its QObject refcount reaches zero.  It is
usual for the parent (bus) to hold the final reference but there are
cases where something else holds a reference so "free" is a misleading
name.

Call object_unparent(obj) directly instead of having a qdev wrapper
function.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>

15 files changed, 21 insertions, 29 deletions

diff --git a/hw/acpi/piix4.c b/hw/acpi/piix4.c
index 3bcd89056..93849c8d3 100644
--- a/hw/acpi/piix4.c
+++ b/hw/acpi/piix4.c
@@ -328,7 +328,7 @@ static void acpi_piix_eject_slot(PIIX4PMState *s, unsigned slots)
             if (pc->no_hotplug) {
                 slot_free = false;
             } else {
-                qdev_free(qdev);
+                object_unparent(OBJECT(qdev));
             }
         }
     }
diff --git a/hw/core/qdev.c b/hw/core/qdev.c
index 533f6dd12..e374a9399 100644
--- a/hw/core/qdev.c
+++ b/hw/core/qdev.c
@@ -164,7 +164,7 @@ int qdev_init(DeviceState *dev)
     if (local_err != NULL) {
         qerror_report_err(local_err);
         error_free(local_err);
-        qdev_free(dev);
+        object_unparent(OBJECT(dev));
         return -1;
     }
     return 0;
@@ -258,7 +258,7 @@ void qbus_reset_all_fn(void *opaque)
 int qdev_simple_unplug_cb(DeviceState *dev)
 {
     /* just zap it */
-    qdev_free(dev);
+    object_unparent(OBJECT(dev));
     return 0;
 }
 
@@ -280,12 +280,6 @@ void qdev_init_nofail(DeviceState *dev)
     }
 }
 
-/* Unlink device from bus and free the structure.  */
-void qdev_free(DeviceState *dev)
-{
-    object_unparent(OBJECT(dev));
-}
-
 void qdev_machine_creation_done(void)
 {
     /*
@@ -458,7 +452,7 @@ static void bus_unparent(Object *obj)
 
     while ((kid = QTAILQ_FIRST(&bus->children)) != NULL) {
         DeviceState *dev = kid->child;
-        qdev_free(dev);
+        object_unparent(OBJECT(dev));
     }
     if (bus->parent) {
         QLIST_REMOVE(bus, sibling);
diff --git a/hw/pci/pci-hotplug-old.c b/hw/pci/pci-hotplug-old.c
index 619fe473e..8dbc3c1ca 100644
--- a/hw/pci/pci-hotplug-old.c
+++ b/hw/pci/pci-hotplug-old.c
@@ -248,7 +248,7 @@ static PCIDevice *qemu_pci_hot_add_storage(Monitor *mon,
         }
         dev = pci_create(bus, devfn, "virtio-blk-pci");
         if (qdev_prop_set_drive(&dev->qdev, "drive", dinfo->bdrv) < 0) {
-            qdev_free(&dev->qdev);
+            object_unparent(OBJECT(dev));
             dev = NULL;
             break;
         }
diff --git a/hw/pci/pci_bridge.c b/hw/pci/pci_bridge.c
index e6b22b860..290ababb8 100644
--- a/hw/pci/pci_bridge.c
+++ b/hw/pci/pci_bridge.c
@@ -391,7 +391,7 @@ void pci_bridge_exitfn(PCIDevice *pci_dev)
     pci_bridge_region_cleanup(s, s->windows);
     memory_region_destroy(&s->address_space_mem);
     memory_region_destroy(&s->address_space_io);
-    /* qbus_free() is called automatically by qdev_free() */
+    /* qbus_free() is called automatically during device deletion */
 }
 
 /*
diff --git a/hw/pci/pcie.c b/hw/pci/pcie.c
index 268a69664..ca60cf217 100644
--- a/hw/pci/pcie.c
+++ b/hw/pci/pcie.c
@@ -251,7 +251,7 @@ static int pcie_cap_slot_hotplug(DeviceState *qdev,
                                    PCI_EXP_SLTSTA_PDS);
         pcie_cap_slot_event(d, PCI_EXP_HP_EV_PDC);
     } else {
-        qdev_free(&pci_dev->qdev);
+        object_unparent(OBJECT(pci_dev));
         pci_word_test_and_clear_mask(exp_cap + PCI_EXP_SLTSTA,
                                      PCI_EXP_SLTSTA_PDS);
         pcie_cap_slot_event(d, PCI_EXP_HP_EV_PDC);
diff --git a/hw/pci/shpc.c b/hw/pci/shpc.c
index 0bbd36e27..576244b9f 100644
--- a/hw/pci/shpc.c
+++ b/hw/pci/shpc.c
@@ -254,7 +254,7 @@ static void shpc_free_devices_in_slot(SHPCDevice *shpc, int slot)
          ++devfn) {
         PCIDevice *affected_dev = shpc->sec_bus->devices[devfn];
         if (affected_dev) {
-            qdev_free(&affected_dev->qdev);
+            object_unparent(OBJECT(affected_dev));
         }
     }
 }
diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c
index cd67db5e5..f93a81c7c 100644
--- a/hw/s390x/virtio-ccw.c
+++ b/hw/s390x/virtio-ccw.c
@@ -1239,7 +1239,7 @@ static int virtio_ccw_busdev_unplug(DeviceState *dev)
 
     css_generate_sch_crws(sch->cssid, sch->ssid, sch->schid, 1, 0);
 
-    qdev_free(dev);
+    object_unparent(OBJECT(dev));
     return 0;
 }
 
diff --git a/hw/scsi/scsi-bus.c b/hw/scsi/scsi-bus.c
index 24ec52f8f..ea916d146 100644
--- a/hw/scsi/scsi-bus.c
+++ b/hw/scsi/scsi-bus.c
@@ -178,7 +178,7 @@ static int scsi_qdev_init(DeviceState *qdev)
         d = scsi_device_find(bus, dev->channel, dev->id, dev->lun);
         assert(d);
         if (d->lun == dev->lun && dev != d) {
-            qdev_free(&d->qdev);
+            object_unparent(OBJECT(d));
         }
     }
 
@@ -231,13 +231,13 @@ SCSIDevice *scsi_bus_legacy_add_drive(SCSIBus *bus, BlockDriverState *bdrv,
     }
     if (qdev_prop_set_drive(dev, "drive", bdrv) < 0) {
         error_setg(errp, "Setting drive property failed");
-        qdev_free(dev);
+        object_unparent(OBJECT(dev));
         return NULL;
     }
     object_property_set_bool(OBJECT(dev), true, "realized", &err);
     if (err != NULL) {
         error_propagate(errp, err);
-        qdev_free(dev);
+        object_unparent(OBJECT(dev));
         return NULL;
     }
     return SCSI_DEVICE(dev);
diff --git a/hw/usb/bus.c b/hw/usb/bus.c
index 72d5b9222..ca329bef2 100644
--- a/hw/usb/bus.c
+++ b/hw/usb/bus.c
@@ -356,8 +356,9 @@ void usb_port_location(USBPort *downstream, USBPort *upstream, int portnr)
 
 void usb_unregister_port(USBBus *bus, USBPort *port)
 {
-    if (port->dev)
-        qdev_free(&port->dev->qdev);
+    if (port->dev) {
+        object_unparent(OBJECT(port->dev));
+    }
     QTAILQ_REMOVE(&bus->free, port, next);
     bus->nfree--;
 }
@@ -505,7 +506,7 @@ int usb_device_delete_addr(int busnr, int addr)
         return -1;
     dev = port->dev;
 
-    qdev_free(&dev->qdev);
+    object_unparent(OBJECT(dev));
     return 0;
 }
 
diff --git a/hw/usb/dev-storage.c b/hw/usb/dev-storage.c
index 1d81ac2a6..c434c5680 100644
--- a/hw/usb/dev-storage.c
+++ b/hw/usb/dev-storage.c
@@ -703,7 +703,7 @@ static USBDevice *usb_msd_init(USBBus *bus, const char *filename)
         return NULL;
     }
     if (qdev_prop_set_drive(&dev->qdev, "drive", dinfo->bdrv) < 0) {
-        qdev_free(&dev->qdev);
+        object_unparent(OBJECT(dev));
         return NULL;
     }
     if (qdev_init(&dev->qdev) < 0)
diff --git a/hw/usb/host-legacy.c b/hw/usb/host-legacy.c
index 3a5f70572..3cc9c4282 100644
--- a/hw/usb/host-legacy.c
+++ b/hw/usb/host-legacy.c
@@ -132,7 +132,7 @@ USBDevice *usb_host_device_open(USBBus *bus, const char *devname)
     return dev;
 
 fail:
-    qdev_free(&dev->qdev);
+    object_unparent(OBJECT(dev));
     return NULL;
 }
 
diff --git a/hw/virtio/virtio-bus.c b/hw/virtio/virtio-bus.c
index 6849a018a..e6b103c99 100644
--- a/hw/virtio/virtio-bus.c
+++ b/hw/virtio/virtio-bus.c
@@ -67,7 +67,6 @@ void virtio_bus_reset(VirtioBusState *bus)
 /* Destroy the VirtIODevice */
 void virtio_bus_destroy_device(VirtioBusState *bus)
 {
-    DeviceState *qdev;
     BusState *qbus = BUS(bus);
     VirtioBusClass *klass = VIRTIO_BUS_GET_CLASS(bus);
     DPRINTF("%s: remove device.\n", qbus->name);
@@ -76,8 +75,7 @@ void virtio_bus_destroy_device(VirtioBusState *bus)
         if (klass->device_unplug != NULL) {
             klass->device_unplug(qbus->parent);
         }
-        qdev = DEVICE(bus->vdev);
-        qdev_free(qdev);
+        object_unparent(OBJECT(bus->vdev));
         bus->vdev = NULL;
     }
 }
diff --git a/hw/xen/xen_platform.c b/hw/xen/xen_platform.c
index 79bf0b33d..70875e412 100644
--- a/hw/xen/xen_platform.c
+++ b/hw/xen/xen_platform.c
@@ -95,7 +95,7 @@ static void unplug_nic(PCIBus *b, PCIDevice *d, void *o)
     if (pci_get_word(d->config + PCI_CLASS_DEVICE) ==
             PCI_CLASS_NETWORK_ETHERNET
             && strcmp(d->name, "xen-pci-passthrough") != 0) {
-        qdev_free(DEVICE(d));
+        object_unparent(OBJECT(d));
     }
 }
 
diff --git a/include/hw/qdev-core.h b/include/hw/qdev-core.h
index e191ca0bd..f2043a69c 100644
--- a/include/hw/qdev-core.h
+++ b/include/hw/qdev-core.h
@@ -221,7 +221,6 @@ void qdev_init_nofail(DeviceState *dev);
 void qdev_set_legacy_instance_id(DeviceState *dev, int alias_id,
                                  int required_for_version);
 void qdev_unplug(DeviceState *dev, Error **errp);
-void qdev_free(DeviceState *dev);
 int qdev_simple_unplug_cb(DeviceState *dev);
 void qdev_machine_creation_done(void);
 bool qdev_machine_modified(void);
diff --git a/qdev-monitor.c b/qdev-monitor.c
index 9099d3d8f..8e8ed4c13 100644
--- a/qdev-monitor.c
+++ b/qdev-monitor.c
@@ -526,7 +526,7 @@ DeviceState *qdev_device_add(QemuOpts *opts)
         qdev->id = id;
     }
     if (qemu_opt_foreach(opts, set_property, qdev, 1) != 0) {
-        qdev_free(qdev);
+        object_unparent(OBJECT(qdev));
         object_unref(OBJECT(qdev));
         return NULL;
     }