static int ne_create_vm_ioctl()

in drivers/virt/nitro_enclaves/ne_misc_dev.c [1676:1809]

• 96 lines of code
• 14 McCabe index (conditional complexity)

static int ne_create_vm_ioctl(struct ne_pci_dev *ne_pci_dev, u64 __user *slot_uid)
{
	struct ne_pci_dev_cmd_reply cmd_reply = {};
	int enclave_fd = -1;
	struct file *enclave_file = NULL;
	unsigned int i = 0;
	struct ne_enclave *ne_enclave = NULL;
	struct pci_dev *pdev = ne_pci_dev->pdev;
	int rc = -EINVAL;
	struct slot_alloc_req slot_alloc_req = {};

	mutex_lock(&ne_cpu_pool.mutex);

	for (i = 0; i < ne_cpu_pool.nr_parent_vm_cores; i++)
		if (!cpumask_empty(ne_cpu_pool.avail_threads_per_core[i]))
			break;

	if (i == ne_cpu_pool.nr_parent_vm_cores) {
		dev_err_ratelimited(ne_misc_dev.this_device,
				    "No CPUs available in CPU pool\n");

		mutex_unlock(&ne_cpu_pool.mutex);

		return -NE_ERR_NO_CPUS_AVAIL_IN_POOL;
	}

	mutex_unlock(&ne_cpu_pool.mutex);

	ne_enclave = kzalloc(sizeof(*ne_enclave), GFP_KERNEL);
	if (!ne_enclave)
		return -ENOMEM;

	mutex_lock(&ne_cpu_pool.mutex);

	ne_enclave->nr_parent_vm_cores = ne_cpu_pool.nr_parent_vm_cores;
	ne_enclave->nr_threads_per_core = ne_cpu_pool.nr_threads_per_core;
	ne_enclave->numa_node = ne_cpu_pool.numa_node;

	mutex_unlock(&ne_cpu_pool.mutex);

	ne_enclave->threads_per_core = kcalloc(ne_enclave->nr_parent_vm_cores,
					       sizeof(*ne_enclave->threads_per_core),
					       GFP_KERNEL);
	if (!ne_enclave->threads_per_core) {
		rc = -ENOMEM;

		goto free_ne_enclave;
	}

	for (i = 0; i < ne_enclave->nr_parent_vm_cores; i++)
		if (!zalloc_cpumask_var(&ne_enclave->threads_per_core[i], GFP_KERNEL)) {
			rc = -ENOMEM;

			goto free_cpumask;
		}

	if (!zalloc_cpumask_var(&ne_enclave->vcpu_ids, GFP_KERNEL)) {
		rc = -ENOMEM;

		goto free_cpumask;
	}

	enclave_fd = get_unused_fd_flags(O_CLOEXEC);
	if (enclave_fd < 0) {
		rc = enclave_fd;

		dev_err_ratelimited(ne_misc_dev.this_device,
				    "Error in getting unused fd [rc=%d]\n", rc);

		goto free_cpumask;
	}

	enclave_file = anon_inode_getfile("ne-vm", &ne_enclave_fops, ne_enclave, O_RDWR);
	if (IS_ERR(enclave_file)) {
		rc = PTR_ERR(enclave_file);

		dev_err_ratelimited(ne_misc_dev.this_device,
				    "Error in anon inode get file [rc=%d]\n", rc);

		goto put_fd;
	}

	rc = ne_do_request(pdev, SLOT_ALLOC,
			   &slot_alloc_req, sizeof(slot_alloc_req),
			   &cmd_reply, sizeof(cmd_reply));
	if (rc < 0) {
		dev_err_ratelimited(ne_misc_dev.this_device,
				    "Error in slot alloc [rc=%d]\n", rc);

		goto put_file;
	}

	init_waitqueue_head(&ne_enclave->eventq);
	ne_enclave->has_event = false;
	mutex_init(&ne_enclave->enclave_info_mutex);
	ne_enclave->max_mem_regions = cmd_reply.mem_regions;
	INIT_LIST_HEAD(&ne_enclave->mem_regions_list);
	ne_enclave->mm = current->mm;
	ne_enclave->slot_uid = cmd_reply.slot_uid;
	ne_enclave->state = NE_STATE_INIT;

	list_add(&ne_enclave->enclave_list_entry, &ne_pci_dev->enclaves_list);

	if (copy_to_user(slot_uid, &ne_enclave->slot_uid, sizeof(ne_enclave->slot_uid))) {
		/*
		 * As we're holding the only reference to 'enclave_file', fput()
		 * will call ne_enclave_release() which will do a proper cleanup
		 * of all so far allocated resources, leaving only the unused fd
		 * for us to free.
		 */
		fput(enclave_file);
		put_unused_fd(enclave_fd);

		return -EFAULT;
	}

	fd_install(enclave_fd, enclave_file);

	return enclave_fd;

put_file:
	fput(enclave_file);
put_fd:
	put_unused_fd(enclave_fd);
free_cpumask:
	free_cpumask_var(ne_enclave->vcpu_ids);
	for (i = 0; i < ne_enclave->nr_parent_vm_cores; i++)
		free_cpumask_var(ne_enclave->threads_per_core[i]);
	kfree(ne_enclave->threads_per_core);
free_ne_enclave:
	kfree(ne_enclave);

	return rc;
}