static int gve_probe()

in google/gve/gve_main.c [2612:2746]

• 108 lines of code
• 10 McCabe index (conditional complexity)

static int gve_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
{
	int max_tx_queues, max_rx_queues;
	struct net_device *dev;
	__be32 __iomem *db_bar;
	struct gve_registers __iomem *reg_bar;
	struct gve_priv *priv;
	int err;

	err = pci_enable_device(pdev);
	if (err)
		return err;

	err = pci_request_regions(pdev, gve_driver_name);
	if (err)
		goto abort_with_enabled;

	pci_set_master(pdev);

	err = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
	if (err) {
		dev_err(&pdev->dev, "Failed to set dma mask: err=%d\n", err);
		goto abort_with_pci_region;
	}

	reg_bar = pci_iomap(pdev, GVE_REGISTER_BAR, 0);
	if (!reg_bar) {
		dev_err(&pdev->dev, "Failed to map pci bar!\n");
		err = -ENOMEM;
		goto abort_with_pci_region;
	}

	db_bar = pci_iomap(pdev, GVE_DOORBELL_BAR, 0);
	if (!db_bar) {
		dev_err(&pdev->dev, "Failed to map doorbell bar!\n");
		err = -ENOMEM;
		goto abort_with_reg_bar;
	}

	gve_write_version(&reg_bar->driver_version);
	/* Get max queues to alloc etherdev */
	max_tx_queues = ioread32be(&reg_bar->max_tx_queues);
	max_rx_queues = ioread32be(&reg_bar->max_rx_queues);
	/* Alloc and setup the netdev and priv */
	dev = alloc_etherdev_mqs(sizeof(*priv), max_tx_queues, max_rx_queues);
	if (!dev) {
		dev_err(&pdev->dev, "could not allocate netdev\n");
		err = -ENOMEM;
		goto abort_with_db_bar;
	}
	SET_NETDEV_DEV(dev, &pdev->dev);
	pci_set_drvdata(pdev, dev);
	dev->ethtool_ops = &gve_ethtool_ops;
	dev->netdev_ops = &gve_netdev_ops;
	dev->queue_mgmt_ops = &gve_queue_mgmt_ops;
	dev->stat_ops = &gve_stat_ops;

	/* Set default and supported features.
	 *
	 * Features might be set in other locations as well (such as
	 * `gve_adminq_describe_device`).
	 */
	dev->hw_features = NETIF_F_HIGHDMA;
	dev->hw_features |= NETIF_F_SG;
	dev->hw_features |= NETIF_F_HW_CSUM;
	dev->hw_features |= NETIF_F_TSO;
	dev->hw_features |= NETIF_F_TSO6;
	dev->hw_features |= NETIF_F_TSO_ECN;
	dev->hw_features |= NETIF_F_RXCSUM;
	dev->hw_features |= NETIF_F_RXHASH;
	dev->features = dev->hw_features;
	dev->watchdog_timeo = 5 * HZ;
	dev->min_mtu = ETH_MIN_MTU;
	netif_carrier_off(dev);

	priv = netdev_priv(dev);
	priv->dev = dev;
	priv->pdev = pdev;
	priv->msg_enable = DEFAULT_MSG_LEVEL;
	priv->reg_bar0 = reg_bar;
	priv->db_bar2 = db_bar;
	priv->service_task_flags = 0x0;
	priv->state_flags = 0x0;
	priv->ethtool_flags = 0x0;
	priv->data_buffer_size_dqo = GVE_DEFAULT_RX_BUFFER_SIZE;
	priv->max_rx_buffer_size = GVE_DEFAULT_RX_BUFFER_SIZE;

	gve_set_probe_in_progress(priv);
	priv->gve_wq = alloc_ordered_workqueue("gve", 0);
	if (!priv->gve_wq) {
		dev_err(&pdev->dev, "Could not allocate workqueue");
		err = -ENOMEM;
		goto abort_with_netdev;
	}
	INIT_WORK(&priv->service_task, gve_service_task);
	INIT_WORK(&priv->stats_report_task, gve_stats_report_task);
	priv->tx_cfg.max_queues = max_tx_queues;
	priv->rx_cfg.max_queues = max_rx_queues;

	err = gve_init_priv(priv, false);
	if (err)
		goto abort_with_wq;

	err = register_netdev(dev);
	if (err)
		goto abort_with_gve_init;

	dev_info(&pdev->dev, "GVE version %s\n", gve_version_str);
	dev_info(&pdev->dev, "GVE queue format %d\n", (int)priv->queue_format);
	gve_clear_probe_in_progress(priv);
	queue_work(priv->gve_wq, &priv->service_task);
	return 0;

abort_with_gve_init:
	gve_teardown_priv_resources(priv);

abort_with_wq:
	destroy_workqueue(priv->gve_wq);

abort_with_netdev:
	free_netdev(dev);

abort_with_db_bar:
	pci_iounmap(pdev, db_bar);

abort_with_reg_bar:
	pci_iounmap(pdev, reg_bar);

abort_with_pci_region:
	pci_release_regions(pdev);

abort_with_enabled:
	pci_disable_device(pdev);
	return err;
}