Provides an ability to do an optional second stage initialization of an object created with -object/object-add/object_add commands.
Patch adds interface that provides realize() callback, which is called after the object properties were set upon completion of -object/object-add/object_add command, if the type implements OBJECT_REALIZE_INTERFACE. It allows to: * generalize second stage backend initialization instead of adding custom APIs to perform it * early error detection of backend initialization at -object/ object-add/object_add time rather than through a proxy DEVICE object that tries to use backend. Signed-off-by: Igor Mammedov <imamm...@redhat.com> --- Next patch will convert virtio_rng to a new interface as an example. The same interface will be useful for memory backend. --- include/qom/object_interfaces.h | 53 +++++++++++++++++++++++++++++++++++++++ qmp.c | 6 ++++ qom/Makefile.objs | 1 + qom/object_interfaces.c | 33 ++++++++++++++++++++++++ vl.c | 14 ++++++++++ 5 files changed, 107 insertions(+), 0 deletions(-) create mode 100644 include/qom/object_interfaces.h create mode 100644 qom/object_interfaces.c diff --git a/include/qom/object_interfaces.h b/include/qom/object_interfaces.h new file mode 100644 index 0000000..8a42d46 --- /dev/null +++ b/include/qom/object_interfaces.h @@ -0,0 +1,53 @@ +#ifndef OBJECT_INTERFACES_H +#define OBJECT_INTERFACES_H + +#include "qom/object.h" + +#define TYPE_OBJECT_REALIZE_INTERFACE "object-realize-interface" + +#define OBJECT_REALIZE_INTERFACE_CLASS(klass) \ + OBJECT_CLASS_CHECK(ObjectRealizeInterfaceClass, (klass), \ + TYPE_OBJECT_REALIZE_INTERFACE) +#define OBJECT_REALIZE_INTERFACE_GET_CLASS(obj) \ + OBJECT_GET_CLASS(ObjectRealizeInterfaceClass, (obj), \ + TYPE_OBJECT_REALIZE_INTERFACE) +#define OBJECT_REALIZE_INTERFACE(obj) \ + INTERFACE_CHECK(ObjectRealizeInterface, (obj), \ + TYPE_OBJECT_REALIZE_INTERFACE) + + +typedef struct ObjectRealizeInterface { + /* <private> */ + Object Parent; +} ObjectRealizeInterface; + +/** + * ObjectRealizeInterfaceClass: + * @parent_class: the base class + * @realize: callback to be called after @obj's properties are set. + * + * Interface is designed to work with -object/object-add/object_add + * commands and provides an optional ability to do the second stage + * initialization of the object after its properties were set. + * + * For objects created without using -object/object-add/object_add, + * @call_object_realize_interface should be called manually if object's + * type implements OBJECT_REALIZE_INTERFACE. + */ +typedef struct ObjectRealizeInterfaceClass { + /* <private> */ + InterfaceClass parent_class; + + void (*realize)(ObjectRealizeInterface *obj, Error **errp); +} ObjectRealizeInterfaceClass; + +/** + * call_object_realize_interface: + * @obj: the object whose realize() method is called + * @errp: if an error occurs, a pointer to an area to store the error + * + * Wrapper to call realize() method if one of obj's types + * implements OBJECT_REALIZE_INTERFACE, otherwise the call does nothing. + */ +void call_object_realize_interface(Object *obj, Error **errp); +#endif diff --git a/qmp.c b/qmp.c index a67e0c4..3ed78cd 100644 --- a/qmp.c +++ b/qmp.c @@ -27,6 +27,7 @@ #include "qapi/qmp/qobject.h" #include "qapi/qmp-input-visitor.h" #include "hw/boards.h" +#include "qom/object_interfaces.h" NameInfo *qmp_query_name(Error **errp) { @@ -554,6 +555,11 @@ void object_add(const char *type, const char *id, const QDict *qdict, } } + call_object_realize_interface(obj, &local_err); + if (local_err) { + goto out; + } + object_property_add_child(container_get(object_get_root(), "/objects"), id, obj, &local_err); out: diff --git a/qom/Makefile.objs b/qom/Makefile.objs index 6a93ac7..985003b 100644 --- a/qom/Makefile.objs +++ b/qom/Makefile.objs @@ -1,2 +1,3 @@ common-obj-y = object.o container.o qom-qobject.o common-obj-y += cpu.o +common-obj-y += object_interfaces.o diff --git a/qom/object_interfaces.c b/qom/object_interfaces.c new file mode 100644 index 0000000..d2aa722 --- /dev/null +++ b/qom/object_interfaces.c @@ -0,0 +1,33 @@ +#include "qom/object_interfaces.h" +#include "qemu/module.h" + +void call_object_realize_interface(Object *obj, Error **errp) +{ + ObjectRealizeInterface *ori; + ObjectRealizeInterfaceClass *oric; + + ori = (ObjectRealizeInterface *) + object_dynamic_cast(obj, TYPE_OBJECT_REALIZE_INTERFACE); + if (!ori) { + return; + } + + oric = OBJECT_REALIZE_INTERFACE_GET_CLASS(ori); + if (oric->realize) { + oric->realize(ori, errp); + } +} + + +static void register_types(void) +{ + static const TypeInfo realize_interface_info = { + .name = TYPE_OBJECT_REALIZE_INTERFACE, + .parent = TYPE_INTERFACE, + .class_size = sizeof(ObjectRealizeInterfaceClass), + }; + + type_register_static(&realize_interface_info); +} + +type_init(register_types) diff --git a/vl.c b/vl.c index 45f9177..1620393 100644 --- a/vl.c +++ b/vl.c @@ -170,6 +170,7 @@ int main(int argc, char **argv) #include "ui/qemu-spice.h" #include "qapi/string-input-visitor.h" +#include "qom/object_interfaces.h" //#define DEBUG_NET //#define DEBUG_SLIRP @@ -2798,6 +2799,7 @@ static int object_create(QemuOpts *opts, void *opaque) { const char *type = qemu_opt_get(opts, "qom-type"); const char *id = qemu_opts_id(opts); + Error *local_err = NULL; Object *obj; g_assert(type != NULL); @@ -2813,9 +2815,21 @@ static int object_create(QemuOpts *opts, void *opaque) return -1; } + call_object_realize_interface(obj, &local_err); + if (local_err) { + goto out; + } + object_property_add_child(container_get(object_get_root(), "/objects"), id, obj, NULL); + +out: object_unref(obj); + if (local_err) { + qerror_report_err(local_err); + error_free(local_err); + return -1; + } return 0; } -- 1.7.1