migration: Create vmstate_register_any()

We have lots of cases where we are using an instance_id==0 when we
should be using VMSTATE_INSTANCE_ID_ANY (-1).  Basically everything
that can have more than one needs to have a proper instance_id or -1
and the system will take one for it.

vmstate_register_any(): We register with -1.

Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <20231020090731.28701-2-quintela@redhat.com>

1 files changed, 17 insertions, 0 deletions

diff --git a/include/migration/vmstate.h b/include/migration/vmstate.h
index 1af1818..1ea97cc 100644
--- a/include/migration/vmstate.h
+++ b/include/migration/vmstate.h
@@ -1230,6 +1230,23 @@ static inline int vmstate_register(VMStateIf *obj, int instance_id,
                                           opaque, -1, 0, NULL);
 }
 
+/**
+ * vmstate_register_any() - legacy function to register state
+ * serialisation description and let the function choose the id
+ *
+ * New code shouldn't be using this function as QOM-ified devices have
+ * dc->vmsd to store the serialisation description.
+ *
+ * Returns: 0 on success, -1 on failure
+ */
+static inline int vmstate_register_any(VMStateIf *obj,
+                                       const VMStateDescription *vmsd,
+                                       void *opaque)
+{
+    return vmstate_register_with_alias_id(obj, VMSTATE_INSTANCE_ID_ANY, vmsd,
+                                          opaque, -1, 0, NULL);
+}
+
 void vmstate_unregister(VMStateIf *obj, const VMStateDescription *vmsd,
                         void *opaque);