/* Traffic control (tc): setup interface queuing desciplines.

*

* VILLASnode uses these functions to setup the network emulation feature.

*

* Author: Steffen Vogel <post@steffenvogel.de>

* SPDX-FileCopyrightText: 2014-2023 Institute for Automation of Complex Power Systems, RWTH Aachen University

* SPDX-License-Identifier: Apache-2.0

*/

#include <linux/if_ether.h>

#include <netlink/route/cls/fw.h>

#include <netlink/route/qdisc/prio.h>

#include <villas/exceptions.hpp>

#include <villas/kernel/if.hpp>

#include <villas/kernel/kernel.hpp>

#include <villas/kernel/nl.hpp>

#include <villas/kernel/tc.hpp>

#include <villas/utils.hpp>

using namespace villas;

using namespace villas::kernel;

int villas::kernel::tc::prio(Interface *i, struct rtnl_qdisc **qd,

tc_hdl_t handle, tc_hdl_t parent, int bands) {

int ret;

struct nl_sock *sock = nl::init();

struct rtnl_qdisc *q = rtnl_qdisc_alloc();

ret = kernel::loadModule("sch_prio");

if (ret)

throw RuntimeError("Failed to load kernel module: sch_prio ({})", ret);

/* This is the default priomap used by the tc-prio qdisc

* We will use the first 'bands' bands internally */

uint8_t map[] = QDISC_PRIO_DEFAULT_PRIOMAP;

for (unsigned i = 0; i < std::size(map); i++)

map[i] += bands;

rtnl_tc_set_link(TC_CAST(q), i->nl_link);

rtnl_tc_set_parent(TC_CAST(q), parent);

rtnl_tc_set_handle(TC_CAST(q), handle);

rtnl_tc_set_kind(TC_CAST(q), "prio");

rtnl_qdisc_prio_set_bands(q, bands + 3);

rtnl_qdisc_prio_set_priomap(q, map, sizeof(map));

ret = rtnl_qdisc_add(sock, q, NLM_F_CREATE | NLM_F_REPLACE);

*qd = q;

auto logger = Log::get("kernel");

logger->debug("Added prio qdisc with {} bands to interface '{}'", bands,

rtnl_link_get_name(i->nl_link));

return ret;

}

int villas::kernel::tc::mark(Interface *i, struct rtnl_cls **cls,

tc_hdl_t flowid, uint32_t mark) {

int ret;

struct nl_sock *sock = nl::init();

struct rtnl_cls *c = rtnl_cls_alloc();

ret = kernel::loadModule("cls_fw");

if (ret)

throw RuntimeError("Failed to load kernel module: cls_fw");

rtnl_tc_set_link(TC_CAST(c), i->nl_link);

rtnl_tc_set_handle(TC_CAST(c), mark);

rtnl_tc_set_kind(TC_CAST(c), "fw");

rtnl_cls_set_protocol(c, ETH_P_ALL);

rtnl_fw_set_classid(c, flowid);

rtnl_fw_set_mask(c, 0xFFFFFFFF);

ret = rtnl_cls_add(sock, c, NLM_F_CREATE);

*cls = c;

auto logger = Log::get("kernel");

logger->debug("Added fwmark classifier with mark {} to interface '{}'", mark,

rtnl_link_get_name(i->nl_link));

return ret;

}

int villas::kernel::tc::reset(Interface *i) {

struct nl_sock *sock = nl::init();

// We restore the default pfifo_fast qdisc, by deleting ours

return rtnl_qdisc_delete(sock, i->tc_qdisc);

}