qdev: Base object creation on QDict rather than QemuOpts

QDicts are both what QMP natively uses and what the keyval parser
produces. Going through QemuOpts isn't useful for either one, so switch
the main device creation function to QDicts. By sharing more code with
the -object/object-add code path, we can even reduce the code size a
bit.

This commit doesn't remove the detour through QemuOpts from any code
path yet, but it allows the following commits to do so.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20211008133442.141332-15-kwolf@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Peter Krempa <pkrempa@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

1 files changed, 13 insertions, 10 deletions

diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index f503f28..09e173a 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -858,9 +858,11 @@ static void failover_add_primary(VirtIONet *n, Error **errp)
         return;
     }
 
-    dev = qdev_device_add(n->primary_opts, &err);
+    dev = qdev_device_add_from_qdict(n->primary_opts,
+                                     n->primary_opts_from_json,
+                                     &err);
     if (err) {
-        qemu_opts_del(n->primary_opts);
+        qobject_unref(n->primary_opts);
         n->primary_opts = NULL;
     } else {
         object_unref(OBJECT(dev));
@@ -3287,7 +3289,9 @@ static void virtio_net_migration_state_notifier(Notifier *notifier, void *data)
 }
 
 static bool failover_hide_primary_device(DeviceListener *listener,
-                                         QemuOpts *device_opts, Error **errp)
+                                         const QDict *device_opts,
+                                         bool from_json,
+                                         Error **errp)
 {
     VirtIONet *n = container_of(listener, VirtIONet, primary_listener);
     const char *standby_id;
@@ -3295,7 +3299,7 @@ static bool failover_hide_primary_device(DeviceListener *listener,
     if (!device_opts) {
         return false;
     }
-    standby_id = qemu_opt_get(device_opts, "failover_pair_id");
+    standby_id = qdict_get_try_str(device_opts, "failover_pair_id");
     if (g_strcmp0(standby_id, n->netclient_name) != 0) {
         return false;
     }
@@ -3306,12 +3310,8 @@ static bool failover_hide_primary_device(DeviceListener *listener,
         return false;
     }
 
-    /*
-     * Having a weak reference here should be okay because a device can't be
-     * deleted while it's hidden. This will be replaced soon with a QDict that
-     * has a clearer ownership model.
-     */
-    n->primary_opts = device_opts;
+    n->primary_opts = qdict_clone_shallow(device_opts);
+    n->primary_opts_from_json = from_json;
 
     /* failover_primary_hidden is set during feature negotiation */
     return qatomic_read(&n->failover_primary_hidden);
@@ -3502,8 +3502,11 @@ static void virtio_net_device_unrealize(DeviceState *dev)
     g_free(n->vlans);
 
     if (n->failover) {
+        qobject_unref(n->primary_opts);
         device_listener_unregister(&n->primary_listener);
         remove_migration_state_change_notifier(&n->migration_state);
+    } else {
+        assert(n->primary_opts == NULL);
     }
 
     max_queues = n->multiqueue ? n->max_queues : 1;