qemu

remote-obj.c (5018B)

---

 /*
  * Copyright © 2020, 2021 Oracle and/or its affiliates.
  *
  * This work is licensed under the terms of the GNU GPL-v2, version 2 or later.
  *
  * See the COPYING file in the top-level directory.
  *
  */
 
 #include "qemu/osdep.h"
 
 #include "qemu/error-report.h"
 #include "qemu/notify.h"
 #include "qom/object_interfaces.h"
 #include "hw/qdev-core.h"
 #include "io/channel.h"
 #include "hw/qdev-core.h"
 #include "hw/remote/machine.h"
 #include "io/channel-util.h"
 #include "qapi/error.h"
 #include "sysemu/sysemu.h"
 #include "hw/pci/pci.h"
 #include "qemu/sockets.h"
 #include "monitor/monitor.h"
 
 #define TYPE_REMOTE_OBJECT "x-remote-object"
 OBJECT_DECLARE_TYPE(RemoteObject, RemoteObjectClass, REMOTE_OBJECT)
 
 struct RemoteObjectClass {
     ObjectClass parent_class;
 
     unsigned int nr_devs;
     unsigned int max_devs;
 };
 
 struct RemoteObject {
     /* private */
     Object parent;
 
     Notifier machine_done;
 
     int32_t fd;
     char *devid;
 
     QIOChannel *ioc;
 
     DeviceState *dev;
     DeviceListener listener;
 };
 
 static void remote_object_set_fd(Object *obj, const char *str, Error **errp)
 {
     RemoteObject *o = REMOTE_OBJECT(obj);
     int fd = -1;
 
     fd = monitor_fd_param(monitor_cur(), str, errp);
     if (fd == -1) {
         error_prepend(errp, "Could not parse remote object fd %s:", str);
         return;
     }
 
     if (!fd_is_socket(fd)) {
         error_setg(errp, "File descriptor '%s' is not a socket", str);
         close(fd);
         return;
     }
 
     o->fd = fd;
 }
 
 static void remote_object_set_devid(Object *obj, const char *str, Error **errp)
 {
     RemoteObject *o = REMOTE_OBJECT(obj);
 
     g_free(o->devid);
 
     o->devid = g_strdup(str);
 }
 
 static void remote_object_unrealize_listener(DeviceListener *listener,
                                              DeviceState *dev)
 {
     RemoteObject *o = container_of(listener, RemoteObject, listener);
 
     if (o->dev == dev) {
         object_unref(OBJECT(o));
     }
 }
 
 static void remote_object_machine_done(Notifier *notifier, void *data)
 {
     RemoteObject *o = container_of(notifier, RemoteObject, machine_done);
     DeviceState *dev = NULL;
     QIOChannel *ioc = NULL;
     Coroutine *co = NULL;
     RemoteCommDev *comdev = NULL;
     Error *err = NULL;
 
     dev = qdev_find_recursive(sysbus_get_default(), o->devid);
     if (!dev || !object_dynamic_cast(OBJECT(dev), TYPE_PCI_DEVICE)) {
         error_report("%s is not a PCI device", o->devid);
         return;
     }
 
     ioc = qio_channel_new_fd(o->fd, &err);
     if (!ioc) {
         error_report_err(err);
         return;
     }
     qio_channel_set_blocking(ioc, false, NULL);
 
     o->dev = dev;
 
     o->listener.unrealize = remote_object_unrealize_listener;
     device_listener_register(&o->listener);
 
     /* co-routine should free this. */
     comdev = g_new0(RemoteCommDev, 1);
     *comdev = (RemoteCommDev) {
         .ioc = ioc,
         .dev = PCI_DEVICE(dev),
     };
 
     co = qemu_coroutine_create(mpqemu_remote_msg_loop_co, comdev);
     qemu_coroutine_enter(co);
 }
 
 static void remote_object_init(Object *obj)
 {
     RemoteObjectClass *k = REMOTE_OBJECT_GET_CLASS(obj);
     RemoteObject *o = REMOTE_OBJECT(obj);
 
     if (k->nr_devs >= k->max_devs) {
         error_report("Reached maximum number of devices: %u", k->max_devs);
         return;
     }
 
     o->ioc = NULL;
     o->fd = -1;
     o->devid = NULL;
 
     k->nr_devs++;
 
     o->machine_done.notify = remote_object_machine_done;
     qemu_add_machine_init_done_notifier(&o->machine_done);
 }
 
 static void remote_object_finalize(Object *obj)
 {
     RemoteObjectClass *k = REMOTE_OBJECT_GET_CLASS(obj);
     RemoteObject *o = REMOTE_OBJECT(obj);
 
     device_listener_unregister(&o->listener);
 
     if (o->ioc) {
         qio_channel_shutdown(o->ioc, QIO_CHANNEL_SHUTDOWN_BOTH, NULL);
         qio_channel_close(o->ioc, NULL);
     }
 
     object_unref(OBJECT(o->ioc));
 
     k->nr_devs--;
     g_free(o->devid);
 }
 
 static void remote_object_class_init(ObjectClass *klass, void *data)
 {
     RemoteObjectClass *k = REMOTE_OBJECT_CLASS(klass);
 
     /*
      * Limit number of supported devices to 1. This is done to avoid devices
      * from one VM accessing the RAM of another VM. This is done until we
      * start using separate address spaces for individual devices.
      */
     k->max_devs = 1;
     k->nr_devs = 0;
 
     object_class_property_add_str(klass, "fd", NULL, remote_object_set_fd);
     object_class_property_add_str(klass, "devid", NULL,
                                   remote_object_set_devid);
 }
 
 static const TypeInfo remote_object_info = {
     .name = TYPE_REMOTE_OBJECT,
     .parent = TYPE_OBJECT,
     .instance_size = sizeof(RemoteObject),
     .instance_init = remote_object_init,
     .instance_finalize = remote_object_finalize,
     .class_size = sizeof(RemoteObjectClass),
     .class_init = remote_object_class_init,
     .interfaces = (InterfaceInfo[]) {
         { TYPE_USER_CREATABLE },
         { }
     }
 };
 
 static void register_types(void)
 {
     type_register_static(&remote_object_info);
 }
 
 type_init(register_types);