VirtIODevice *virtio_serial_init(DeviceState *dev, virtio_serial_conf *conf) { VirtIOSerial *vser; VirtIODevice *vdev; uint32_t i, max_supported_ports; if (!conf->max_virtserial_ports) return NULL; /* Each port takes 2 queues, and one pair is for the control queue */ max_supported_ports = VIRTIO_PCI_QUEUE_MAX / 2 - 1; if (conf->max_virtserial_ports > max_supported_ports) { error_report("maximum ports supported: %u", max_supported_ports); return NULL; } vdev = virtio_common_init("virtio-serial", VIRTIO_ID_CONSOLE, sizeof(struct virtio_console_config), sizeof(VirtIOSerial)); vser = DO_UPCAST(VirtIOSerial, vdev, vdev); /* Spawn a new virtio-serial bus on which the ports will ride as devices */ vser->bus = virtser_bus_new(dev); vser->bus->vser = vser; QTAILQ_INIT(&vser->ports); vser->bus->max_nr_ports = conf->max_virtserial_ports; vser->ivqs = qemu_malloc(conf->max_virtserial_ports * sizeof(VirtQueue *)); vser->ovqs = qemu_malloc(conf->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->config.max_nr_ports = tswap32(conf->max_virtserial_ports); vser->ports_map = qemu_mallocz(((conf->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->vdev.get_features = get_features; vser->vdev.get_config = get_config; vser->vdev.set_config = set_config; vser->qdev = dev; /* * Register for the savevm section with the virtio-console name * to preserve backward compat */ register_savevm(dev, "virtio-console", -1, 3, virtio_serial_save, virtio_serial_load, vser); return vdev; }