1 files changed, 104 insertions, 0 deletions
diff --git a/event-loop-base.c b/event-loop-base.c
new file mode 100644
index 0000000000..a924c73a7c
--- /dev/null
+++ b/event-loop-base.c
@@ -0,0 +1,104 @@
+/*
+ * QEMU event-loop base
+ *
+ * Copyright (C) 2022 Red Hat Inc
+ *
+ * Authors:
+ *  Stefan Hajnoczi <stefanha@redhat.com>
+ *  Nicolas Saenz Julienne <nsaenzju@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "qom/object_interfaces.h"
+#include "qapi/error.h"
+#include "sysemu/event-loop-base.h"
+
+typedef struct {
+    const char *name;
+    ptrdiff_t offset; /* field's byte offset in EventLoopBase struct */
+} EventLoopBaseParamInfo;
+
+static EventLoopBaseParamInfo aio_max_batch_info = {
+    "aio-max-batch", offsetof(EventLoopBase, aio_max_batch),
+};
+
+static void event_loop_base_get_param(Object *obj, Visitor *v,
+        const char *name, void *opaque, Error **errp)
+{
+    EventLoopBase *event_loop_base = EVENT_LOOP_BASE(obj);
+    EventLoopBaseParamInfo *info = opaque;
+    int64_t *field = (void *)event_loop_base + info->offset;
+
+    visit_type_int64(v, name, field, errp);
+}
+
+static void event_loop_base_set_param(Object *obj, Visitor *v,
+        const char *name, void *opaque, Error **errp)
+{
+    EventLoopBaseClass *bc = EVENT_LOOP_BASE_GET_CLASS(obj);
+    EventLoopBase *base = EVENT_LOOP_BASE(obj);
+    EventLoopBaseParamInfo *info = opaque;
+    int64_t *field = (void *)base + info->offset;
+    int64_t value;
+
+    if (!visit_type_int64(v, name, &value, errp)) {
+        return;
+    }
+
+    if (value < 0) {
+        error_setg(errp, "%s value must be in range [0, %" PRId64 "]",
+                   info->name, INT64_MAX);
+        return;
+    }
+
+    *field = value;
+
+    if (bc->update_params) {
+        bc->update_params(base, errp);
+    }
+
+    return;
+}
+
+static void event_loop_base_complete(UserCreatable *uc, Error **errp)
+{
+    EventLoopBaseClass *bc = EVENT_LOOP_BASE_GET_CLASS(uc);
+    EventLoopBase *base = EVENT_LOOP_BASE(uc);
+
+    if (bc->init) {
+        bc->init(base, errp);
+    }
+}
+
+static void event_loop_base_class_init(ObjectClass *klass, void *class_data)
+{
+    UserCreatableClass *ucc = USER_CREATABLE_CLASS(klass);
+    ucc->complete = event_loop_base_complete;
+
+    object_class_property_add(klass, "aio-max-batch", "int",
+                              event_loop_base_get_param,
+                              event_loop_base_set_param,
+                              NULL, &aio_max_batch_info);
+}
+
+static const TypeInfo event_loop_base_info = {
+    .name = TYPE_EVENT_LOOP_BASE,
+    .parent = TYPE_OBJECT,
+    .instance_size = sizeof(EventLoopBase),
+    .class_size = sizeof(EventLoopBaseClass),
+    .class_init = event_loop_base_class_init,
+    .abstract = true,
+    .interfaces = (InterfaceInfo[]) {
+        { TYPE_USER_CREATABLE },
+        { }
+    }
+};
+
+static void register_types(void)
+{
+    type_register_static(&event_loop_base_info);
+}
+type_init(register_types);