static int mlx5_vdpa_dev_add()

in mlx5/net/mlx5_vnet.c [2538:2673]

• 116 lines of code
• 22 McCabe index (conditional complexity)

static int mlx5_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name,
			     const struct vdpa_dev_set_config *add_config)
{
	struct mlx5_vdpa_mgmtdev *mgtdev = container_of(v_mdev, struct mlx5_vdpa_mgmtdev, mgtdev);
	struct virtio_net_config *config;
	struct mlx5_core_dev *pfmdev;
	struct mlx5_vdpa_dev *mvdev;
	struct mlx5_vdpa_net *ndev;
	struct mlx5_core_dev *mdev;
	u32 max_vqs;
	u16 mtu;
	int err;

	if (mgtdev->ndev)
		return -ENOSPC;

	mdev = mgtdev->madev->mdev;
	if (!(MLX5_CAP_DEV_VDPA_EMULATION(mdev, virtio_queue_type) &
	    MLX5_VIRTIO_EMULATION_CAP_VIRTIO_QUEUE_TYPE_SPLIT)) {
		dev_warn(mdev->device, "missing support for split virtqueues\n");
		return -EOPNOTSUPP;
	}

	max_vqs = MLX5_CAP_DEV_VDPA_EMULATION(mdev, max_num_virtio_queues);
	if (max_vqs < 2) {
		dev_warn(mdev->device,
			 "%d virtqueues are supported. At least 2 are required\n",
			 max_vqs);
		return -EAGAIN;
	}

	if (add_config->mask & BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MAX_VQP)) {
		if (add_config->net.max_vq_pairs > max_vqs / 2)
			return -EINVAL;
		max_vqs = min_t(u32, max_vqs, 2 * add_config->net.max_vq_pairs);
	} else {
		max_vqs = 2;
	}

	ndev = vdpa_alloc_device(struct mlx5_vdpa_net, mvdev.vdev, mdev->device, &mlx5_vdpa_ops,
				 name, false);
	if (IS_ERR(ndev))
		return PTR_ERR(ndev);

	ndev->mvdev.mlx_features = mgtdev->mgtdev.supported_features;
	ndev->mvdev.max_vqs = max_vqs;
	mvdev = &ndev->mvdev;
	mvdev->mdev = mdev;

	ndev->vqs = kcalloc(max_vqs, sizeof(*ndev->vqs), GFP_KERNEL);
	ndev->event_cbs = kcalloc(max_vqs + 1, sizeof(*ndev->event_cbs), GFP_KERNEL);
	if (!ndev->vqs || !ndev->event_cbs) {
		err = -ENOMEM;
		goto err_alloc;
	}

	init_mvqs(ndev);
	mutex_init(&ndev->reslock);
	config = &ndev->config;
	err = query_mtu(mdev, &mtu);
	if (err)
		goto err_mtu;

	ndev->config.mtu = cpu_to_mlx5vdpa16(mvdev, mtu);

	if (get_link_state(mvdev))
		ndev->config.status |= cpu_to_mlx5vdpa16(mvdev, VIRTIO_NET_S_LINK_UP);
	else
		ndev->config.status &= cpu_to_mlx5vdpa16(mvdev, ~VIRTIO_NET_S_LINK_UP);

	if (add_config->mask & (1 << VDPA_ATTR_DEV_NET_CFG_MACADDR)) {
		memcpy(ndev->config.mac, add_config->net.mac, ETH_ALEN);
	} else {
		err = mlx5_query_nic_vport_mac_address(mdev, 0, 0, config->mac);
		if (err)
			goto err_mtu;
	}

	if (!is_zero_ether_addr(config->mac)) {
		pfmdev = pci_get_drvdata(pci_physfn(mdev->pdev));
		err = mlx5_mpfs_add_mac(pfmdev, config->mac);
		if (err)
			goto err_mtu;

		ndev->mvdev.mlx_features |= BIT_ULL(VIRTIO_NET_F_MAC);
	}

	config->max_virtqueue_pairs = cpu_to_mlx5vdpa16(mvdev, mlx5_vdpa_max_qps(max_vqs));
	mvdev->vdev.dma_dev = &mdev->pdev->dev;
	err = mlx5_vdpa_alloc_resources(&ndev->mvdev);
	if (err)
		goto err_mpfs;

	if (MLX5_CAP_GEN(mvdev->mdev, umem_uid_0)) {
		err = mlx5_vdpa_create_mr(mvdev, NULL);
		if (err)
			goto err_res;
	}

	err = alloc_resources(ndev);
	if (err)
		goto err_mr;

	mvdev->wq = create_singlethread_workqueue("mlx5_vdpa_wq");
	if (!mvdev->wq) {
		err = -ENOMEM;
		goto err_res2;
	}

	ndev->nb.notifier_call = event_handler;
	mlx5_notifier_register(mdev, &ndev->nb);
	mvdev->vdev.mdev = &mgtdev->mgtdev;
	err = _vdpa_register_device(&mvdev->vdev, 2 * mlx5_vdpa_max_qps(max_vqs) + 1);
	if (err)
		goto err_reg;

	mgtdev->ndev = ndev;
	return 0;

err_reg:
	destroy_workqueue(mvdev->wq);
err_res2:
	free_resources(ndev);
err_mr:
	mlx5_vdpa_destroy_mr(mvdev);
err_res:
	mlx5_vdpa_free_resources(&ndev->mvdev);
err_mpfs:
	if (!is_zero_ether_addr(config->mac))
		mlx5_mpfs_del_mac(pfmdev, config->mac);
err_mtu:
	mutex_destroy(&ndev->reslock);
err_alloc:
	put_device(&mvdev->vdev.dev);
	return err;
}