static int query_virtqueue()

in mlx5/net/mlx5_vnet.c [1072:1107]

• 31 lines of code
• 3 McCabe index (conditional complexity)

static int query_virtqueue(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtqueue *mvq,
			   struct mlx5_virtq_attr *attr)
{
	int outlen = MLX5_ST_SZ_BYTES(query_virtio_net_q_out);
	u32 in[MLX5_ST_SZ_DW(query_virtio_net_q_in)] = {};
	void *out;
	void *obj_context;
	void *cmd_hdr;
	int err;

	out = kzalloc(outlen, GFP_KERNEL);
	if (!out)
		return -ENOMEM;

	cmd_hdr = MLX5_ADDR_OF(query_virtio_net_q_in, in, general_obj_in_cmd_hdr);

	MLX5_SET(general_obj_in_cmd_hdr, cmd_hdr, opcode, MLX5_CMD_OP_QUERY_GENERAL_OBJECT);
	MLX5_SET(general_obj_in_cmd_hdr, cmd_hdr, obj_type, MLX5_OBJ_TYPE_VIRTIO_NET_Q);
	MLX5_SET(general_obj_in_cmd_hdr, cmd_hdr, obj_id, mvq->virtq_id);
	MLX5_SET(general_obj_in_cmd_hdr, cmd_hdr, uid, ndev->mvdev.res.uid);
	err = mlx5_cmd_exec(ndev->mvdev.mdev, in, sizeof(in), out, outlen);
	if (err)
		goto err_cmd;

	obj_context = MLX5_ADDR_OF(query_virtio_net_q_out, out, obj_context);
	memset(attr, 0, sizeof(*attr));
	attr->state = MLX5_GET(virtio_net_q_object, obj_context, state);
	attr->available_index = MLX5_GET(virtio_net_q_object, obj_context, hw_available_index);
	attr->used_index = MLX5_GET(virtio_net_q_object, obj_context, hw_used_index);
	kfree(out);
	return 0;

err_cmd:
	kfree(out);
	return err;
}