static void virtio_serial_device_realize(DeviceState *dev, Error **errp) { VirtIODevice *vdev = VIRTIO_DEVICE(dev); VirtIOSerial *vser = VIRTIO_SERIAL(dev); uint32_t i, max_supported_ports; if (!vser->serial.max_virtserial_ports) { error_setg(errp, "Maximum number of serial ports not specified"); return; } /* Each port takes 2 queues, and one pair is for the control queue */ max_supported_ports = VIRTIO_QUEUE_MAX / 2 - 1; if (vser->serial.max_virtserial_ports > max_supported_ports) { error_setg(errp, "maximum ports supported: %u", max_supported_ports); return; } /* We don't support emergency write, skip it for now. */ /* TODO: cleaner fix, depending on host features. */ virtio_init(vdev, "virtio-serial", VIRTIO_ID_CONSOLE, offsetof(struct virtio_console_config, emerg_wr)); /* Spawn a new virtio-serial bus on which the ports will ride as devices */ qbus_create_inplace(&vser->bus, sizeof(vser->bus), TYPE_VIRTIO_SERIAL_BUS, dev, vdev->bus_name); qbus_set_hotplug_handler(BUS(&vser->bus), DEVICE(vser), errp); vser->bus.vser = vser; QTAILQ_INIT(&vser->ports); vser->bus.max_nr_ports = vser->serial.max_virtserial_ports; vser->ivqs = g_malloc(vser->serial.max_virtserial_ports * sizeof(VirtQueue *)); vser->ovqs = g_malloc(vser->serial.max_virtserial_ports * sizeof(VirtQueue *)); /* Add a queue for host to guest transfers for port 0 (backward compat) */ vser->ivqs[0] = virtio_add_queue(vdev, 128, handle_input); /* Add a queue for guest to host transfers for port 0 (backward compat) */ vser->ovqs[0] = virtio_add_queue(vdev, 128, handle_output); /* TODO: host to guest notifications can get dropped * if the queue fills up. Implement queueing in host, * this might also make it possible to reduce the control * queue size: as guest preposts buffers there, * this will save 4Kbyte of guest memory per entry. */ /* control queue: host to guest */ vser->c_ivq = virtio_add_queue(vdev, 32, control_in); /* control queue: guest to host */ vser->c_ovq = virtio_add_queue(vdev, 32, control_out); for (i = 1; i < vser->bus.max_nr_ports; i++) { /* Add a per-port queue for host to guest transfers */ vser->ivqs[i] = virtio_add_queue(vdev, 128, handle_input); /* Add a per-per queue for guest to host transfers */ vser->ovqs[i] = virtio_add_queue(vdev, 128, handle_output); } vser->ports_map = g_malloc0(((vser->serial.max_virtserial_ports + 31) / 32) * sizeof(vser->ports_map[0])); /* * Reserve location 0 for a console port for backward compat * (old kernel, new qemu) */ mark_port_added(vser, 0); vser->post_load = NULL; QLIST_INSERT_HEAD(&vserdevices.devices, vser, next); }