sai_status_t SwitchStateBase::vs_create_hostif_tap_interface()

in vslib/SwitchStateBaseHostif.cpp [516:694]

• 115 lines of code
• 16 McCabe index (conditional complexity)

sai_status_t SwitchStateBase::vs_create_hostif_tap_interface(
        _In_ uint32_t attr_count,
        _In_ const sai_attribute_t *attr_list)
{
    SWSS_LOG_ENTER();

    // validate SAI_HOSTIF_ATTR_TYPE

    auto attr_type = sai_metadata_get_attr_by_id(SAI_HOSTIF_ATTR_TYPE, attr_count, attr_list);

    if (attr_type == NULL)
    {
        SWSS_LOG_ERROR("attr SAI_HOSTIF_ATTR_TYPE was not passed");

        return SAI_STATUS_FAILURE;
    }

    /* The genetlink host interface is created to associate trap group to genetlink family and multicast group
     * created by driver. It does not create any netdev interface. Hence skipping tap interface creation
     */
    if (attr_type->value.s32 == SAI_HOSTIF_TYPE_GENETLINK)
    {
        SWSS_LOG_DEBUG("Skipping tap create for hostif type genetlink");

        return SAI_STATUS_SUCCESS;
    }

    if (attr_type->value.s32 != SAI_HOSTIF_TYPE_NETDEV)
    {
        SWSS_LOG_ERROR("only SAI_HOSTIF_TYPE_NETDEV is supported");

        return SAI_STATUS_FAILURE;
    }

    // validate SAI_HOSTIF_ATTR_OBJ_ID

    auto attr_obj_id = sai_metadata_get_attr_by_id(SAI_HOSTIF_ATTR_OBJ_ID, attr_count, attr_list);

    if (attr_obj_id == NULL)
    {
        SWSS_LOG_ERROR("attr SAI_HOSTIF_ATTR_OBJ_ID was not passed");

        return SAI_STATUS_FAILURE;
    }

    sai_object_id_t obj_id = attr_obj_id->value.oid;

    sai_object_type_t ot = objectTypeQuery(obj_id);

    if (ot == SAI_OBJECT_TYPE_VLAN)
    {
        SWSS_LOG_DEBUG("Skipping tap creation for hostif with object type VLAN");
        return SAI_STATUS_SUCCESS;
    }

    if (ot != SAI_OBJECT_TYPE_PORT)
    {
        SWSS_LOG_ERROR("SAI_HOSTIF_ATTR_OBJ_ID=%s expected to be PORT but is: %s",
                sai_serialize_object_id(obj_id).c_str(),
                sai_serialize_object_type(ot).c_str());

        return SAI_STATUS_FAILURE;
    }

    // validate SAI_HOSTIF_ATTR_NAME

    auto attr_name = sai_metadata_get_attr_by_id(SAI_HOSTIF_ATTR_NAME, attr_count, attr_list);

    if (attr_name == NULL)
    {
        SWSS_LOG_ERROR("attr SAI_HOSTIF_ATTR_NAME was not passed");

        return SAI_STATUS_FAILURE;
    }

    if (strnlen(attr_name->value.chardata, sizeof(attr_name->value.chardata)) >= MAX_INTERFACE_NAME_LEN)
    {
        SWSS_LOG_ERROR("interface name is too long: %.*s", MAX_INTERFACE_NAME_LEN, attr_name->value.chardata);

        return SAI_STATUS_FAILURE;
    }

    std::string name = std::string(attr_name->value.chardata);

    // create TAP device

    SWSS_LOG_INFO("creating hostif %s", name.c_str());

    int tapfd = vs_create_tap_device(name.c_str(), IFF_TAP | IFF_MULTI_QUEUE | IFF_NO_PI);

    if (tapfd < 0)
    {
        SWSS_LOG_ERROR("failed to create TAP device for %s", name.c_str());

        return SAI_STATUS_FAILURE;
    }

    SWSS_LOG_INFO("created TAP device for %s, fd: %d", name.c_str(), tapfd);

    sai_attribute_t attr;

    memset(&attr, 0, sizeof(attr));

    attr.id = SAI_SWITCH_ATTR_SRC_MAC_ADDRESS;

    sai_status_t status = get(SAI_OBJECT_TYPE_SWITCH, m_switch_id, 1, &attr);

    if (status != SAI_STATUS_SUCCESS)
    {
        SWSS_LOG_ERROR("failed to get SAI_SWITCH_ATTR_SRC_MAC_ADDRESS on switch %s: %s",
                sai_serialize_object_id(m_switch_id).c_str(),
                sai_serialize_status(status).c_str());
    }

    int err = vs_set_dev_mac_address(name.c_str(), attr.value.mac);

    if (err < 0)
    {
        SWSS_LOG_ERROR("failed to set MAC address %s for %s",
                sai_serialize_mac(attr.value.mac).c_str(),
                name.c_str());

        close(tapfd);

        return SAI_STATUS_FAILURE;
    }

    std::string vname = vs_get_veth_name(name, obj_id);

    int mtu = ETH_FRAME_BUFFER_SIZE;

    sai_attribute_t attrmtu;

    attrmtu.id = SAI_PORT_ATTR_MTU;

    if (get(SAI_OBJECT_TYPE_PORT, obj_id, 1, &attrmtu) == SAI_STATUS_SUCCESS)
    {
        mtu = attrmtu.value.u32;

        SWSS_LOG_INFO("setting new MTU: %d on %s", mtu, vname.c_str());
    }

    vs_set_dev_mtu(vname.c_str(), mtu);

    attr.id = SAI_PORT_ATTR_ADMIN_STATE;

    status = get(SAI_OBJECT_TYPE_PORT, obj_id, 1, &attr);

    if (status != SAI_STATUS_SUCCESS)
    {
        SWSS_LOG_ERROR("failed to get admin state for port %s",
                sai_serialize_object_id(obj_id).c_str());

        return status;
    }

    if (ifup(vname.c_str(), obj_id, attr.value.booldata, false))
    {
        SWSS_LOG_ERROR("ifup failed on %s", vname.c_str());

        return SAI_STATUS_FAILURE;
    }

    if (!hostif_create_tap_veth_forwarding(name, tapfd, obj_id))
    {
        SWSS_LOG_ERROR("forwarding rule on %s was not added", name.c_str());
    }

    SWSS_LOG_INFO("mapping interface %s to port id %s",
            vname.c_str(),
            sai_serialize_object_id(obj_id).c_str());

    setIfNameToPortId(vname, obj_id);
    setPortIdToTapName(obj_id, name);

    SWSS_LOG_INFO("created tap interface %s", name.c_str());

    return SAI_STATUS_SUCCESS;
}