htb.c

/*
 * lib/route/qdisc/htb.c        HTB Qdisc
 *
 *      This library is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU Lesser General Public
 *      License as published by the Free Software Foundation version 2.1
 *      of the License.
 *
 * Copyright (c) 2003-2011 Thomas Graf <tgraf@suug.ch>
 * Copyright (c) 2005-2006 Petr Gotthard <petr.gotthard@siemens.com>
 * Copyright (c) 2005-2006 Siemens AG Oesterreich
 */

/**
 * @ingroup qdisc
 * @ingroup class
 * @defgroup qdisc_htb Hierachical Token Bucket (HTB)
 * @{
 */

#include <netlink-private/netlink.h>
#include <netlink-private/tc.h>
#include <netlink/netlink.h>
#include <netlink/cache.h>
#include <netlink/utils.h>
#include <netlink-private/route/tc-api.h>
#include <netlink/route/qdisc.h>
#include <netlink/route/class.h>
#include <netlink/route/link.h>
#include <netlink/route/qdisc/htb.h>

/** @cond SKIP */
#define SCH_HTB_HAS_RATE2QUANTUM        0x01
#define SCH_HTB_HAS_DEFCLS              0x02

#define SCH_HTB_HAS_PRIO                0x001
#define SCH_HTB_HAS_RATE                0x002
#define SCH_HTB_HAS_CEIL                0x004
#define SCH_HTB_HAS_RBUFFER             0x008
#define SCH_HTB_HAS_CBUFFER             0x010
#define SCH_HTB_HAS_QUANTUM             0x020
#define SCH_HTB_HAS_LEVEL               0x040
/** @endcond */

static struct nla_policy htb_policy[TCA_HTB_MAX+1] = {
        [TCA_HTB_INIT]  = { .minlen = sizeof(struct tc_htb_glob) },
        [TCA_HTB_PARMS] = { .minlen = sizeof(struct tc_htb_opt) },
};

static int htb_qdisc_msg_parser(struct rtnl_tc *tc, void *data)
{
        struct nlattr *tb[TCA_HTB_MAX + 1];
        struct rtnl_htb_qdisc *htb = data;
        int err;

        if ((err = tca_parse(tb, TCA_HTB_MAX, tc, htb_policy)) < 0)
                return err;
        
        if (tb[TCA_HTB_INIT]) {
                struct tc_htb_glob opts;

                nla_memcpy(&opts, tb[TCA_HTB_INIT], sizeof(opts));
                htb->qh_rate2quantum = opts.rate2quantum;
                htb->qh_defcls = opts.defcls;
                htb->qh_direct_pkts = opts.direct_pkts;

                htb->qh_mask = (SCH_HTB_HAS_RATE2QUANTUM | SCH_HTB_HAS_DEFCLS);
        }

        return 0;
}

static int htb_class_msg_parser(struct rtnl_tc *tc, void *data)
{
        struct nlattr *tb[TCA_HTB_MAX + 1];
        struct rtnl_htb_class *htb = data;
        int err;

        if ((err = tca_parse(tb, TCA_HTB_MAX, tc, htb_policy)) < 0)
                return err;
        
        if (tb[TCA_HTB_PARMS]) {
                struct tc_htb_opt opts;

                nla_memcpy(&opts, tb[TCA_HTB_PARMS], sizeof(opts));
                htb->ch_prio = opts.prio;
                rtnl_copy_ratespec(&htb->ch_rate, &opts.rate);
                rtnl_copy_ratespec(&htb->ch_ceil, &opts.ceil);
                htb->ch_rbuffer = rtnl_tc_calc_bufsize(nl_ticks2us(opts.buffer),
                                                       opts.rate.rate);
                htb->ch_cbuffer = rtnl_tc_calc_bufsize(nl_ticks2us(opts.cbuffer),
                                                       opts.ceil.rate);
                htb->ch_quantum = opts.quantum;
                htb->ch_level = opts.level;

                rtnl_tc_set_mpu(tc, htb->ch_rate.rs_mpu);
                rtnl_tc_set_overhead(tc, htb->ch_rate.rs_overhead);

                htb->ch_mask = (SCH_HTB_HAS_PRIO | SCH_HTB_HAS_RATE |
                                SCH_HTB_HAS_CEIL | SCH_HTB_HAS_RBUFFER |
                                SCH_HTB_HAS_CBUFFER | SCH_HTB_HAS_QUANTUM |
                                SCH_HTB_HAS_LEVEL);
        }

        return 0;
}

static void htb_qdisc_dump_line(struct rtnl_tc *tc, void *data,
                                struct nl_dump_params *p)
{
        struct rtnl_htb_qdisc *htb = data;

        if (!htb)
                return;

        if (htb->qh_mask & SCH_HTB_HAS_RATE2QUANTUM)
                nl_dump(p, " r2q %u", htb->qh_rate2quantum);

        if (htb->qh_mask & SCH_HTB_HAS_DEFCLS) {
                char buf[64];
                nl_dump(p, " default-class %s",
                        rtnl_tc_handle2str(htb->qh_defcls, buf, sizeof(buf)));
        }
}

static void htb_class_dump_line(struct rtnl_tc *tc, void *data,
                                struct nl_dump_params *p)
{
        struct rtnl_htb_class *htb = data;

        if (!htb)
                return;

        if (htb->ch_mask & SCH_HTB_HAS_RATE) {
                double r, rbit;
                char *ru, *rubit;

                r = nl_cancel_down_bytes(htb->ch_rate.rs_rate, &ru);
                rbit = nl_cancel_down_bits(htb->ch_rate.rs_rate*8, &rubit);

                nl_dump(p, " rate %.2f%s/s (%.0f%s) log %u",
                        r, ru, rbit, rubit, 1<<htb->ch_rate.rs_cell_log);
        }
}

static void htb_class_dump_details(struct rtnl_tc *tc, void *data,
                                   struct nl_dump_params *p)
{
        struct rtnl_htb_class *htb = data;

        if (!htb)
                return;

        /* line 1 */
        if (htb->ch_mask & SCH_HTB_HAS_CEIL) {
                double r, rbit;
                char *ru, *rubit;

                r = nl_cancel_down_bytes(htb->ch_ceil.rs_rate, &ru);
                rbit = nl_cancel_down_bits(htb->ch_ceil.rs_rate*8, &rubit);

                nl_dump(p, " ceil %.2f%s/s (%.0f%s) log %u",
                        r, ru, rbit, rubit, 1<<htb->ch_ceil.rs_cell_log);
        }

        if (htb->ch_mask & SCH_HTB_HAS_PRIO)
                nl_dump(p, " prio %u", htb->ch_prio);

        if (htb->ch_mask & SCH_HTB_HAS_RBUFFER) {
                double b;
                char *bu;

                b = nl_cancel_down_bytes(htb->ch_rbuffer, &bu);
                nl_dump(p, " rbuffer %.2f%s", b, bu);
        }

        if (htb->ch_mask & SCH_HTB_HAS_CBUFFER) {
                double b;
                char *bu;

                b = nl_cancel_down_bytes(htb->ch_cbuffer, &bu);
                nl_dump(p, " cbuffer %.2f%s", b, bu);
        }

        if (htb->ch_mask & SCH_HTB_HAS_QUANTUM)
                nl_dump(p, " quantum %u", htb->ch_quantum);
}

static int htb_qdisc_msg_fill(struct rtnl_tc *tc, void *data,
                              struct nl_msg *msg)
{
        struct rtnl_htb_qdisc *htb = data;
        struct tc_htb_glob opts = {
                .version = TC_HTB_PROTOVER,
                .rate2quantum = 10,
        };

        if (htb) {
                if (htb->qh_mask & SCH_HTB_HAS_RATE2QUANTUM)
                        opts.rate2quantum = htb->qh_rate2quantum;

                if (htb->qh_mask & SCH_HTB_HAS_DEFCLS)
                        opts.defcls = htb->qh_defcls;
        }

        return nla_put(msg, TCA_HTB_INIT, sizeof(opts), &opts);
}

static int htb_class_msg_fill(struct rtnl_tc *tc, void *data,
                              struct nl_msg *msg)
{
        struct rtnl_htb_class *htb = data;
        uint32_t mtu, rtable[RTNL_TC_RTABLE_SIZE], ctable[RTNL_TC_RTABLE_SIZE];
        struct tc_htb_opt opts;
        int buffer, cbuffer;

        if (!htb || !(htb->ch_mask & SCH_HTB_HAS_RATE))
                BUG();

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

        /* if not set, zero (0) is used as priority */
        if (htb->ch_mask & SCH_HTB_HAS_PRIO)
                opts.prio = htb->ch_prio;

        mtu = rtnl_tc_get_mtu(tc);

        rtnl_tc_build_rate_table(tc, &htb->ch_rate, rtable);
        rtnl_rcopy_ratespec(&opts.rate, &htb->ch_rate);

        if (htb->ch_mask & SCH_HTB_HAS_CEIL) {
                rtnl_tc_build_rate_table(tc, &htb->ch_ceil, ctable);
                rtnl_rcopy_ratespec(&opts.ceil, &htb->ch_ceil);
        } else {
                /*
                 * If not set, configured rate is used as ceil, which implies
                 * no borrowing.
                 */
                memcpy(&opts.ceil, &opts.rate, sizeof(struct tc_ratespec));
        }

        if (htb->ch_mask & SCH_HTB_HAS_RBUFFER)
                buffer = htb->ch_rbuffer;
        else
                buffer = opts.rate.rate / nl_get_psched_hz() + mtu; /* XXX */

        opts.buffer = nl_us2ticks(rtnl_tc_calc_txtime(buffer, opts.rate.rate));

        if (htb->ch_mask & SCH_HTB_HAS_CBUFFER)
                cbuffer = htb->ch_cbuffer;
        else
                cbuffer = opts.ceil.rate / nl_get_psched_hz() + mtu; /* XXX */

        opts.cbuffer = nl_us2ticks(rtnl_tc_calc_txtime(cbuffer, opts.ceil.rate));

        if (htb->ch_mask & SCH_HTB_HAS_QUANTUM)
                opts.quantum = htb->ch_quantum;

        NLA_PUT(msg, TCA_HTB_PARMS, sizeof(opts), &opts);
        NLA_PUT(msg, TCA_HTB_RTAB, sizeof(rtable), &rtable);
        NLA_PUT(msg, TCA_HTB_CTAB, sizeof(ctable), &ctable);

        return 0;

nla_put_failure:
        return -NLE_MSGSIZE;
}

static struct rtnl_tc_ops htb_qdisc_ops;
static struct rtnl_tc_ops htb_class_ops;

static struct rtnl_htb_qdisc *htb_qdisc_data(struct rtnl_qdisc *qdisc)
{
        return rtnl_tc_data_check(TC_CAST(qdisc), &htb_qdisc_ops);
}

static struct rtnl_htb_class *htb_class_data(struct rtnl_class *class)
{
        return rtnl_tc_data_check(TC_CAST(class), &htb_class_ops);
}

/**
 * @name Attribute Modifications
 * @{
 */

/**
 * Return rate/quantum ratio of HTB qdisc
 * @arg qdisc           htb qdisc object
 *
 * @return rate/quantum ratio or 0 if unspecified
 */
uint32_t rtnl_htb_get_rate2quantum(struct rtnl_qdisc *qdisc)
{
        struct rtnl_htb_qdisc *htb;

        if ((htb = htb_qdisc_data(qdisc)) &&
            htb->qh_mask & SCH_HTB_HAS_RATE2QUANTUM)
                return htb->qh_rate2quantum;

        return 0;
}

int rtnl_htb_set_rate2quantum(struct rtnl_qdisc *qdisc, uint32_t rate2quantum)
{
        struct rtnl_htb_qdisc *htb;

        if (!(htb = htb_qdisc_data(qdisc)))
                return -NLE_OPNOTSUPP;

        htb->qh_rate2quantum = rate2quantum;
        htb->qh_mask |= SCH_HTB_HAS_RATE2QUANTUM;

        return 0;
}

/**
 * Return default class of HTB qdisc
 * @arg qdisc           htb qdisc object
 *
 * Returns the classid of the class where all unclassified traffic
 * goes to.
 *
 * @return classid or TC_H_UNSPEC if unspecified.
 */
uint32_t rtnl_htb_get_defcls(struct rtnl_qdisc *qdisc)
{
        struct rtnl_htb_qdisc *htb;

        if ((htb = htb_qdisc_data(qdisc)) &&
            htb->qh_mask & SCH_HTB_HAS_DEFCLS)
                return htb->qh_defcls;

        return TC_H_UNSPEC;
}

/**
 * Set default class of the htb qdisc to the specified value
 * @arg qdisc           qdisc to change
 * @arg defcls          new default class
 */
int rtnl_htb_set_defcls(struct rtnl_qdisc *qdisc, uint32_t defcls)
{
        struct rtnl_htb_qdisc *htb;

        if (!(htb = htb_qdisc_data(qdisc)))
                return -NLE_OPNOTSUPP;

        htb->qh_defcls = defcls;
        htb->qh_mask |= SCH_HTB_HAS_DEFCLS;

        return 0;
}

uint32_t rtnl_htb_get_prio(struct rtnl_class *class)
{
        struct rtnl_htb_class *htb;

        if ((htb = htb_class_data(class)) && htb->ch_mask & SCH_HTB_HAS_PRIO)
                return htb->ch_prio;

        return 0;
}

int rtnl_htb_set_prio(struct rtnl_class *class, uint32_t prio)
{
        struct rtnl_htb_class *htb;

        if (!(htb = htb_class_data(class)))
                return -NLE_OPNOTSUPP;

        htb->ch_prio = prio;
        htb->ch_mask |= SCH_HTB_HAS_PRIO;

        return 0;
}

/**
 * Return rate of HTB class
 * @arg class           htb class object
 *
 * @return Rate in bytes/s or 0 if unspecified.
 */
uint32_t rtnl_htb_get_rate(struct rtnl_class *class)
{
        struct rtnl_htb_class *htb;

        if ((htb = htb_class_data(class)) && htb->ch_mask & SCH_HTB_HAS_RATE)
                return htb->ch_rate.rs_rate;

        return 0;
}

/**
 * Set rate of HTB class
 * @arg class           htb class object
 * @arg rate            new rate in bytes per second
 *
 * @return 0 on success or a negative error code.
 */
int rtnl_htb_set_rate(struct rtnl_class *class, uint32_t rate)
{
        struct rtnl_htb_class *htb;

        if (!(htb = htb_class_data(class)))
                return -NLE_OPNOTSUPP;

        htb->ch_rate.rs_cell_log = UINT8_MAX; /* use default value */
        htb->ch_rate.rs_rate = rate;
        htb->ch_mask |= SCH_HTB_HAS_RATE;

        return 0;
}

/**
 * Return ceil rate of HTB class
 * @arg class           htb class object
 *
 * @return Ceil rate in bytes/s or 0 if unspecified
 */
uint32_t rtnl_htb_get_ceil(struct rtnl_class *class)
{
        struct rtnl_htb_class *htb;

        if ((htb = htb_class_data(class)) && htb->ch_mask & SCH_HTB_HAS_CEIL)
                return htb->ch_ceil.rs_rate;

        return 0;
}

/**
 * Set ceil rate of HTB class
 * @arg class           htb class object
 * @arg ceil            new ceil rate number of bytes per second
 *
 * @return 0 on success or a negative error code.
 */
int rtnl_htb_set_ceil(struct rtnl_class *class, uint32_t ceil)
{
        struct rtnl_htb_class *htb;

        if (!(htb = htb_class_data(class)))
                return -NLE_OPNOTSUPP;

        htb->ch_ceil.rs_cell_log = UINT8_MAX; /* use default value */
        htb->ch_ceil.rs_rate = ceil;
        htb->ch_mask |= SCH_HTB_HAS_CEIL;

        return 0;
}

/**
 * Return burst buffer size of HTB class
 * @arg class           htb class object
 *
 * @return Burst buffer size or 0 if unspecified
 */
uint32_t rtnl_htb_get_rbuffer(struct rtnl_class *class)
{
        struct rtnl_htb_class *htb;

        if ((htb = htb_class_data(class)) &&
             htb->ch_mask & SCH_HTB_HAS_RBUFFER)
                return htb->ch_rbuffer;

        return 0;
}

/**
 * Set size of the rate bucket of HTB class.
 * @arg class           HTB class to be modified.
 * @arg rbuffer         New size in bytes.
 */
int rtnl_htb_set_rbuffer(struct rtnl_class *class, uint32_t rbuffer)
{
        struct rtnl_htb_class *htb;

        if (!(htb = htb_class_data(class)))
                return -NLE_OPNOTSUPP;

        htb->ch_rbuffer = rbuffer;
        htb->ch_mask |= SCH_HTB_HAS_RBUFFER;

        return 0;
}

/**
 * Return ceil burst buffer size of HTB class
 * @arg class           htb class object
 *
 * @return Ceil burst buffer size or 0 if unspecified
 */
uint32_t rtnl_htb_get_cbuffer(struct rtnl_class *class)
{
        struct rtnl_htb_class *htb;

        if ((htb = htb_class_data(class)) &&
             htb->ch_mask & SCH_HTB_HAS_CBUFFER)
                return htb->ch_cbuffer;

        return 0;
}

/**
 * Set size of the ceil bucket of HTB class.
 * @arg class           HTB class to be modified.
 * @arg cbuffer         New size in bytes.
 */
int rtnl_htb_set_cbuffer(struct rtnl_class *class, uint32_t cbuffer)
{
        struct rtnl_htb_class *htb;

        if (!(htb = htb_class_data(class)))
                return -NLE_OPNOTSUPP;

        htb->ch_cbuffer = cbuffer;
        htb->ch_mask |= SCH_HTB_HAS_CBUFFER;

        return 0;
}

/**
 * Return quantum of HTB class
 * @arg class           htb class object
 *
 * See XXX[quantum def]
 *
 * @return Quantum or 0 if unspecified.
 */
uint32_t rtnl_htb_get_quantum(struct rtnl_class *class)
{
        struct rtnl_htb_class *htb;

        if ((htb = htb_class_data(class)) &&
            htb->ch_mask & SCH_HTB_HAS_QUANTUM)
                return htb->ch_quantum;

        return 0;
}

/**
 * Set quantum of HTB class (overwrites value calculated based on r2q)
 * @arg class           htb class object
 * @arg quantum         new quantum in number of bytes
 *
 * See XXX[quantum def]
 *
 * @return 0 on success or a negative error code.
 */
int rtnl_htb_set_quantum(struct rtnl_class *class, uint32_t quantum)
{
        struct rtnl_htb_class *htb;

        if (!(htb = htb_class_data(class)))
                return -NLE_OPNOTSUPP;

        htb->ch_quantum = quantum;
        htb->ch_mask |= SCH_HTB_HAS_QUANTUM;

        return 0;
}

/**
 * Return level of HTB class
 * @arg class           htb class object
 *
 * Returns the level of the HTB class. Leaf classes are assigned level
 * 0, root classes have level (TC_HTB_MAXDEPTH - 1). Interior classes
 * have a level of one less than their parent.
 *
 * @return Level or -NLE_OPNOTSUPP
 */
int rtnl_htb_get_level(struct rtnl_class *class)
{
        struct rtnl_htb_class *htb;

        if ((htb = htb_class_data(class)) && htb->ch_mask & SCH_HTB_HAS_LEVEL)
                return htb->ch_level;

        return -NLE_OPNOTSUPP;
}

/**
 * Set level of HTB class
 * @arg class           htb class object
 * @arg level           new level of HTB class
 *
 * Sets the level of a HTB class. Note that changing the level of a HTB
 * class does not change the level of its in kernel counterpart. This
 * function is provided only to create HTB objects which can be compared
 * against or filtered upon.
 *
 * @return 0 on success or a negative error code.
 */
int rtnl_htb_set_level(struct rtnl_class *class, int level)
{
        struct rtnl_htb_class *htb;

        if (!(htb = htb_class_data(class)))
                return -NLE_OPNOTSUPP;

        htb->ch_level = level;
        htb->ch_mask |= SCH_HTB_HAS_LEVEL;

        return 0;
}

/** @} */

static struct rtnl_tc_ops htb_qdisc_ops = {
        .to_kind                = "htb",
        .to_type                = RTNL_TC_TYPE_QDISC,
        .to_size                = sizeof(struct rtnl_htb_qdisc),
        .to_msg_parser          = htb_qdisc_msg_parser,
        .to_dump[NL_DUMP_LINE]  = htb_qdisc_dump_line,
        .to_msg_fill            = htb_qdisc_msg_fill,
};

static struct rtnl_tc_ops htb_class_ops = {
        .to_kind                = "htb",
        .to_type                = RTNL_TC_TYPE_CLASS,
        .to_size                = sizeof(struct rtnl_htb_class),
        .to_msg_parser          = htb_class_msg_parser,
        .to_dump = {
            [NL_DUMP_LINE]      = htb_class_dump_line,
            [NL_DUMP_DETAILS]   = htb_class_dump_details,
        },
        .to_msg_fill            = htb_class_msg_fill,
};

static void __init htb_init(void)
{
        rtnl_tc_register(&htb_qdisc_ops);
        rtnl_tc_register(&htb_class_ops);
}

static void __exit htb_exit(void)
{
        rtnl_tc_unregister(&htb_qdisc_ops);
        rtnl_tc_unregister(&htb_class_ops);
}

/** @} */