From 269e09f3fc922b800d118d9c8a721be46b5462a3 Mon Sep 17 00:00:00 2001 From: Igor Mammedov Date: Thu, 16 Jan 2014 17:34:38 +0100 Subject: add optional 2nd stage initialization to -object/object-add commands Introduces USER_CREATABLE interface that must be implemented by objects which are designed to created with -object CLI option or object-add QMP command. Interface provides an ability to do an optional second stage initialization of the object created with -object/object-add commands. By providing complete() callback, which is called after the object properties were set. It allows to: * prevents misusing of -object/object-add by filtering out objects that are not designed for it. * generalize second stage backend initialization instead of adding custom APIs to perform it * early error detection of backend initialization at -object/ object-add time rather than through a proxy DEVICE object that tries to use backend. Signed-off-by: Igor Mammedov Reviewed-by: Stefan Hajnoczi Signed-off-by: Luiz Capitulino --- include/qom/object_interfaces.h | 62 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) create mode 100644 include/qom/object_interfaces.h (limited to 'include') diff --git a/include/qom/object_interfaces.h b/include/qom/object_interfaces.h new file mode 100644 index 0000000000..b7922833e1 --- /dev/null +++ b/include/qom/object_interfaces.h @@ -0,0 +1,62 @@ +#ifndef OBJECT_INTERFACES_H +#define OBJECT_INTERFACES_H + +#include "qom/object.h" + +#define TYPE_USER_CREATABLE "user-creatable" + +#define USER_CREATABLE_CLASS(klass) \ + OBJECT_CLASS_CHECK(UserCreatableClass, (klass), \ + TYPE_USER_CREATABLE) +#define USER_CREATABLE_GET_CLASS(obj) \ + OBJECT_GET_CLASS(UserCreatableClass, (obj), \ + TYPE_USER_CREATABLE) +#define USER_CREATABLE(obj) \ + INTERFACE_CHECK(UserCreatable, (obj), \ + TYPE_USER_CREATABLE) + + +typedef struct UserCreatable { + /* */ + Object Parent; +} UserCreatable; + +/** + * UserCreatableClass: + * @parent_class: the base class + * @complete: callback to be called after @obj's properties are set. + * + * Interface is designed to work with -object/object-add/object_add + * commands. + * Interface is mandatory for objects that are designed to be user + * creatable (i.e. -object/object-add/object_add, will accept only + * objects that inherit this interface). + * + * Interface also 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, + * @user_creatable_complete() wrapper should be called manually if + * object's type implements USER_CREATABLE interface and needs + * complete() callback to be called. + */ +typedef struct UserCreatableClass { + /* */ + InterfaceClass parent_class; + + /* */ + void (*complete)(UserCreatable *uc, Error **errp); +} UserCreatableClass; + +/** + * user_creatable_complete: + * @obj: the object whose complete() method is called if defined + * @errp: if an error occurs, a pointer to an area to store the error + * + * Wrapper to call complete() method if one of types it's inherited + * from implements USER_CREATABLE interface, otherwise the call does + * nothing. + */ +void user_creatable_complete(Object *obj, Error **errp); +#endif -- cgit v1.2.3-55-g7522 From 57d3e1b3f52d07d215ed96df946ee01f8d9f9526 Mon Sep 17 00:00:00 2001 From: Igor Mammedov Date: Thu, 16 Jan 2014 17:34:39 +0100 Subject: virtio_rng: replace custom backend API with UserCreatable.complete() callback in addition fix default backend leak by releasing it if its initialization failed. Signed-off-by: Igor Mammedov Reviewed-by: Stefan Hajnoczi Signed-off-by: Luiz Capitulino --- backends/rng.c | 12 ++++++++++-- hw/virtio/virtio-rng.c | 15 +++++++++------ include/sysemu/rng.h | 11 ----------- 3 files changed, 19 insertions(+), 19 deletions(-) (limited to 'include') diff --git a/backends/rng.c b/backends/rng.c index 7bab806ee1..8b8d5a4973 100644 --- a/backends/rng.c +++ b/backends/rng.c @@ -41,9 +41,9 @@ static bool rng_backend_prop_get_opened(Object *obj, Error **errp) return s->opened; } -void rng_backend_open(RngBackend *s, Error **errp) +static void rng_backend_complete(UserCreatable *uc, Error **errp) { - object_property_set_bool(OBJECT(s), true, "opened", errp); + object_property_set_bool(OBJECT(uc), true, "opened", errp); } static void rng_backend_prop_set_opened(Object *obj, bool value, Error **errp) @@ -77,12 +77,20 @@ static void rng_backend_init(Object *obj) NULL); } +static void rng_backend_class_init(ObjectClass *oc, void *data) +{ + UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc); + + ucc->complete = rng_backend_complete; +} + static const TypeInfo rng_backend_info = { .name = TYPE_RNG_BACKEND, .parent = TYPE_OBJECT, .instance_size = sizeof(RngBackend), .instance_init = rng_backend_init, .class_size = sizeof(RngBackendClass), + .class_init = rng_backend_class_init, .abstract = true, .interfaces = (InterfaceInfo[]) { { TYPE_USER_CREATABLE }, diff --git a/hw/virtio/virtio-rng.c b/hw/virtio/virtio-rng.c index 755fdee628..a16e3bc52e 100644 --- a/hw/virtio/virtio-rng.c +++ b/hw/virtio/virtio-rng.c @@ -15,6 +15,7 @@ #include "hw/virtio/virtio.h" #include "hw/virtio/virtio-rng.h" #include "sysemu/rng.h" +#include "qom/object_interfaces.h" static bool is_guest_ready(VirtIORNG *vrng) { @@ -148,6 +149,14 @@ static void virtio_rng_device_realize(DeviceState *dev, Error **errp) if (vrng->conf.rng == NULL) { vrng->conf.default_backend = RNG_RANDOM(object_new(TYPE_RNG_RANDOM)); + user_creatable_complete(OBJECT(vrng->conf.default_backend), + &local_err); + if (local_err) { + error_propagate(errp, local_err); + object_unref(OBJECT(vrng->conf.default_backend)); + return; + } + object_property_add_child(OBJECT(dev), "default-backend", OBJECT(vrng->conf.default_backend), @@ -166,12 +175,6 @@ static void virtio_rng_device_realize(DeviceState *dev, Error **errp) return; } - rng_backend_open(vrng->rng, &local_err); - if (local_err) { - error_propagate(errp, local_err); - return; - } - vrng->vq = virtio_add_queue(vdev, 8, handle_input); assert(vrng->conf.max_bytes <= INT64_MAX); diff --git a/include/sysemu/rng.h b/include/sysemu/rng.h index 7637fac52d..0a27c9b88c 100644 --- a/include/sysemu/rng.h +++ b/include/sysemu/rng.h @@ -79,15 +79,4 @@ void rng_backend_request_entropy(RngBackend *s, size_t size, * to stop tracking any request. */ void rng_backend_cancel_requests(RngBackend *s); - -/** - * rng_backend_open: - * @s: the backend to open - * @errp: a pointer to return the #Error object if an error occurs. - * - * This function will open the backend if it is not already open. Calling this - * function on an already opened backend will not result in an error. - */ -void rng_backend_open(RngBackend *s, Error **errp); - #endif -- cgit v1.2.3-55-g7522