static int ne_setup_msix()

in drivers/virt/nitro_enclaves/ne_pci_dev.c [295:364]

• 44 lines of code
• 6 McCabe index (conditional complexity)

static int ne_setup_msix(struct pci_dev *pdev)
{
	struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev);
	int nr_vecs = 0;
	int rc = -EINVAL;

	nr_vecs = pci_msix_vec_count(pdev);
	if (nr_vecs < 0) {
		rc = nr_vecs;

		dev_err(&pdev->dev, "Error in getting vec count [rc=%d]\n", rc);

		return rc;
	}

	rc = pci_alloc_irq_vectors(pdev, nr_vecs, nr_vecs, PCI_IRQ_MSIX);
	if (rc < 0) {
		dev_err(&pdev->dev, "Error in alloc MSI-X vecs [rc=%d]\n", rc);

		return rc;
	}

	/*
	 * This IRQ gets triggered every time the PCI device responds to a
	 * command request. The reply is then retrieved, reading from the MMIO
	 * space of the PCI device.
	 */
	rc = request_irq(pci_irq_vector(pdev, NE_VEC_REPLY), ne_reply_handler,
			 0, "enclave_cmd", ne_pci_dev);
	if (rc < 0) {
		dev_err(&pdev->dev, "Error in request irq reply [rc=%d]\n", rc);

		goto free_irq_vectors;
	}

	ne_pci_dev->event_wq = create_singlethread_workqueue("ne_pci_dev_wq");
	if (!ne_pci_dev->event_wq) {
		rc = -ENOMEM;

		dev_err(&pdev->dev, "Cannot get wq for dev events [rc=%d]\n", rc);

		goto free_reply_irq_vec;
	}

	INIT_WORK(&ne_pci_dev->notify_work, ne_event_work_handler);

	/*
	 * This IRQ gets triggered every time any enclave's state changes. Its
	 * handler then scans for the changes and propagates them to the user
	 * space.
	 */
	rc = request_irq(pci_irq_vector(pdev, NE_VEC_EVENT), ne_event_handler,
			 0, "enclave_evt", ne_pci_dev);
	if (rc < 0) {
		dev_err(&pdev->dev, "Error in request irq event [rc=%d]\n", rc);

		goto destroy_wq;
	}

	return 0;

destroy_wq:
	destroy_workqueue(ne_pci_dev->event_wq);
free_reply_irq_vec:
	free_irq(pci_irq_vector(pdev, NE_VEC_REPLY), ne_pci_dev);
free_irq_vectors:
	pci_free_irq_vectors(pdev);

	return rc;
}