/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2005 Nuno Antunes <nuno.antunes@gmail.com>
* Copyright (c) 2007 Alexander Motin <mav@freebsd.org>
* Copyright (c) 2019 Lutz Donnerhacke <lutz@donnerhacke.de>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* ng_car - An implementation of committed access rate for netgraph
*
* TODO:
* - Sanitize input config values (impose some limits)
* - Implement DSCP marking for IPv4
* - Decouple functionality into a simple classifier (g/y/r)
* and various action nodes (i.e. shape, dcsp, pcp)
*/
#include <sys/param.h>
#include <sys/errno.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <netgraph/ng_message.h>
#include <netgraph/ng_parse.h>
#include <netgraph/netgraph.h>
#include <netgraph/ng_car.h>
#include "qos.h"
#define NG_CAR_QUEUE_SIZE 100 /* Maximum queue size for SHAPE mode */
#define NG_CAR_QUEUE_MIN_TH 8 /* Minimum RED threshold for SHAPE mode */
/* Hook private info */
struct hookinfo {
hook_p hook; /* this (source) hook */
hook_p dest; /* destination hook */
int64_t tc; /* committed token bucket counter */
int64_t te; /* exceeded/peak token bucket counter */
struct bintime lastRefill; /* last token refill time */
struct ng_car_hookconf conf; /* hook configuration */
struct ng_car_hookstats stats; /* hook stats */
struct mbuf *q[NG_CAR_QUEUE_SIZE]; /* circular packet queue */
u_int q_first; /* first queue element */
u_int q_last; /* last queue element */
struct callout q_callout; /* periodic queue processing routine */
struct mtx q_mtx; /* queue mutex */
};
/* Private information for each node instance */
struct privdata {
node_p node; /* the node itself */
struct hookinfo upper; /* hook to upper layers */
struct hookinfo lower; /* hook to lower layers */
};
typedef struct privdata *priv_p;
static ng_constructor_t ng_car_constructor;
static ng_rcvmsg_t ng_car_rcvmsg;
static ng_shutdown_t ng_car_shutdown;
static ng_newhook_t ng_car_newhook;
static ng_rcvdata_t ng_car_rcvdata;
static ng_disconnect_t ng_car_disconnect;
static void ng_car_refillhook(struct hookinfo *h);
static void ng_car_schedule(struct hookinfo *h);
void ng_car_q_event(node_p node, hook_p hook, void *arg, int arg2);
static void ng_car_enqueue(struct hookinfo *h, item_p item);
/* Parse type for struct ng_car_hookstats */
static const struct ng_parse_struct_field ng_car_hookstats_type_fields[]
= NG_CAR_HOOKSTATS;
static const struct ng_parse_type ng_car_hookstats_type = {
&ng_parse_struct_type,
&ng_car_hookstats_type_fields
};
/* Parse type for struct ng_car_bulkstats */
static const struct ng_parse_struct_field ng_car_bulkstats_type_fields[]
= NG_CAR_BULKSTATS(&ng_car_hookstats_type);
static const struct ng_parse_type ng_car_bulkstats_type = {
&ng_parse_struct_type,
&ng_car_bulkstats_type_fields
};
/* Parse type for struct ng_car_hookconf */
static const struct ng_parse_struct_field ng_car_hookconf_type_fields[]
= NG_CAR_HOOKCONF;
static const struct ng_parse_type ng_car_hookconf_type = {
&ng_parse_struct_type,
&ng_car_hookconf_type_fields
};
/* Parse type for struct ng_car_bulkconf */
static const struct ng_parse_struct_field ng_car_bulkconf_type_fields[]
= NG_CAR_BULKCONF(&ng_car_hookconf_type);
static const struct ng_parse_type ng_car_bulkconf_type = {
&ng_parse_struct_type,
&ng_car_bulkconf_type_fields
};
/* Command list */
static struct ng_cmdlist ng_car_cmdlist[] = {
{
NGM_CAR_COOKIE,
NGM_CAR_GET_STATS,
"getstats",
NULL,
&ng_car_bulkstats_type,
},
{
NGM_CAR_COOKIE,
NGM_CAR_CLR_STATS,
"clrstats",
NULL,
NULL,
},
{
NGM_CAR_COOKIE,
NGM_CAR_GETCLR_STATS,
"getclrstats",
NULL,
&ng_car_bulkstats_type,
},
{
NGM_CAR_COOKIE,
NGM_CAR_GET_CONF,
"getconf",
NULL,
&ng_car_bulkconf_type,
},
{
NGM_CAR_COOKIE,
NGM_CAR_SET_CONF,
"setconf",
&ng_car_bulkconf_type,
NULL,
},
{ 0 }
};
/* Netgraph node type descriptor */
static struct ng_type ng_car_typestruct = {
.version = NG_ABI_VERSION,
.name = NG_CAR_NODE_TYPE,
.constructor = ng_car_constructor,
.rcvmsg = ng_car_rcvmsg,
.shutdown = ng_car_shutdown,
.newhook = ng_car_newhook,
.rcvdata = ng_car_rcvdata,
.disconnect = ng_car_disconnect,
.cmdlist = ng_car_cmdlist,
};
NETGRAPH_INIT(car, &ng_car_typestruct);
/*
* Node constructor
*/
static int
ng_car_constructor(node_p node)
{
priv_p priv;
/* Initialize private descriptor. */
priv = malloc(sizeof(*priv), M_NETGRAPH, M_WAITOK | M_ZERO);
NG_NODE_SET_PRIVATE(node, priv);
priv->node = node;
/*
* Arbitrary default values
*/
priv->upper.hook = NULL;
priv->upper.dest = NULL;
priv->upper.tc = priv->upper.conf.cbs = NG_CAR_CBS_MIN;
priv->upper.te = priv->upper.conf.ebs = NG_CAR_EBS_MIN;
priv->upper.conf.cir = NG_CAR_CIR_DFLT;
priv->upper.conf.green_action = NG_CAR_ACTION_FORWARD;
priv->upper.conf.yellow_action = NG_CAR_ACTION_FORWARD;
priv->upper.conf.red_action = NG_CAR_ACTION_DROP;
priv->upper.conf.mode = 0;
getbinuptime(&priv->upper.lastRefill);
priv->upper.q_first = 0;
priv->upper.q_last = 0;
ng_callout_init(&priv->upper.q_callout);
mtx_init(&priv->upper.q_mtx, "ng_car_u", NULL, MTX_DEF);
priv->lower.hook = NULL;
priv->lower.dest = NULL;
priv->lower.tc = priv->lower.conf.cbs = NG_CAR_CBS_MIN;
priv->lower.te = priv->lower.conf.ebs = NG_CAR_EBS_MIN;
priv->lower.conf.cir = NG_CAR_CIR_DFLT;
priv->lower.conf.green_action = NG_CAR_ACTION_FORWARD;
priv->lower.conf.yellow_action = NG_CAR_ACTION_FORWARD;
priv->lower.conf.red_action = NG_CAR_ACTION_DROP;
priv->lower.conf.mode = 0;
priv->lower.lastRefill = priv->upper.lastRefill;
priv->lower.q_first = 0;
priv->lower.q_last = 0;
ng_callout_init(&priv->lower.q_callout);
mtx_init(&priv->lower.q_mtx, "ng_car_l", NULL, MTX_DEF);
return (0);
}
/*
* Add a hook.
*/
static int
ng_car_newhook(node_p node, hook_p hook, const char *name)
{
const priv_p priv = NG_NODE_PRIVATE(node);
if (strcmp(name, NG_CAR_HOOK_LOWER) == 0) {
priv->lower.hook = hook;
priv->upper.dest = hook;
bzero(&priv->lower.stats, sizeof(priv->lower.stats));
NG_HOOK_SET_PRIVATE(hook, &priv->lower);
} else if (strcmp(name, NG_CAR_HOOK_UPPER) == 0) {
priv->upper.hook = hook;
priv->lower.dest = hook;
bzero(&priv->upper.stats, sizeof(priv->upper.stats));
NG_HOOK_SET_PRIVATE(hook, &priv->upper);
} else
return (EINVAL);
return(0);
}
/*
* Data has arrived.
*/
static int
ng_car_rcvdata(hook_p hook, item_p item )
{
struct hookinfo *const hinfo = NG_HOOK_PRIVATE(hook);
struct mbuf *m;
struct m_qos_color *colp;
enum qos_color col;
int error = 0;
u_int len;
/* If queue is not empty now then enqueue packet. */
if (hinfo->q_first != hinfo->q_last) {
ng_car_enqueue(hinfo, item);
return (0);
}
m = NGI_M(item);
#define NG_CAR_PERFORM_MATCH_ACTION(a,col) \
do { \
switch (a) { \
case NG_CAR_ACTION_FORWARD: \
/* Do nothing. */ \
break; \
case NG_CAR_ACTION_MARK: \
if (colp == NULL) { \
colp = (void *)m_tag_alloc( \
M_QOS_COOKIE, M_QOS_COLOR, \
MTAG_SIZE(m_qos_color), M_NOWAIT); \
if (colp != NULL) \
m_tag_prepend(m, &colp->tag); \
} \
if (colp != NULL) \
colp->color = col; \
break; \
case NG_CAR_ACTION_DROP: \
default: \
/* Drop packet and return. */ \
NG_FREE_ITEM(item); \
++hinfo->stats.dropped_pkts; \
return (0); \
} \
} while (0)
/* Packet is counted as 128 tokens for better resolution */
if (hinfo->conf.opt & NG_CAR_COUNT_PACKETS) {
len = 128;
} else {
len = m->m_pkthdr.len;
}
/* Determine current color of the packet (default green) */
colp = (void *)m_tag_locate(m, M_QOS_COOKIE, M_QOS_COLOR, NULL);
if ((hinfo->conf.opt & NG_CAR_COLOR_AWARE) && (colp != NULL))
col = colp->color;
else
col = QOS_COLOR_GREEN;
/* Check committed token bucket. */
if (hinfo->tc - len >= 0 && col <= QOS_COLOR_GREEN) {
/* This packet is green. */
++hinfo->stats.green_pkts;
hinfo->tc -= len;
NG_CAR_PERFORM_MATCH_ACTION(
hinfo->conf.green_action,
QOS_COLOR_GREEN);
} else {
/* Refill only if not green without it. */
ng_car_refillhook(hinfo);
/* Check committed token bucket again after refill. */
if (hinfo->tc - len >= 0 && col <= QOS_COLOR_GREEN) {
/* This packet is green */
++hinfo->stats.green_pkts;
hinfo->tc -= len;
NG_CAR_PERFORM_MATCH_ACTION(
hinfo->conf.green_action,
QOS_COLOR_GREEN);
/* If not green and mode is SHAPE, enqueue packet. */
} else if (hinfo->conf.mode == NG_CAR_SHAPE) {
ng_car_enqueue(hinfo, item);
return (0);
/* If not green and mode is RED, calculate probability. */
} else if (hinfo->conf.mode == NG_CAR_RED) {
/* Is packet is bigger then extended burst? */
if (len - (hinfo->tc - len) > hinfo->conf.ebs ||
col >= QOS_COLOR_RED) {
/* This packet is definitely red. */
++hinfo->stats.red_pkts;
hinfo->te = 0;
NG_CAR_PERFORM_MATCH_ACTION(
hinfo->conf.red_action,
QOS_COLOR_RED);
/* Use token bucket to simulate RED-like drop
probability. */
} else if (hinfo->te + (len - hinfo->tc) < hinfo->conf.ebs &&
col <= QOS_COLOR_YELLOW) {
/* This packet is yellow */
++hinfo->stats.yellow_pkts;
hinfo->te += len - hinfo->tc;
/* Go to negative tokens. */
hinfo->tc -= len;
NG_CAR_PERFORM_MATCH_ACTION(
hinfo->conf.yellow_action,
QOS_COLOR_YELLOW);
} else {
/* This packet is probably red. */
++hinfo->stats.red_pkts;
hinfo->te = 0;
NG_CAR_PERFORM_MATCH_ACTION(
hinfo->conf.red_action,
QOS_COLOR_RED);
}
/* If not green and mode is SINGLE/DOUBLE RATE. */
} else {
/* Check extended token bucket. */
if (hinfo->te - len >= 0 && col <= QOS_COLOR_YELLOW) {
/* This packet is yellow */
++hinfo->stats.yellow_pkts;
hinfo->te -= len;
NG_CAR_PERFORM_MATCH_ACTION(
hinfo->conf.yellow_action,
QOS_COLOR_YELLOW);
} else {
/* This packet is red */
++hinfo->stats.red_pkts;
NG_CAR_PERFORM_MATCH_ACTION(
hinfo->conf.red_action,
QOS_COLOR_RED);
}
}
}
#undef NG_CAR_PERFORM_MATCH_ACTION
NG_FWD_ITEM_HOOK(error, item, hinfo->dest);
if (error != 0)
++hinfo->stats.errors;
++hinfo->stats.passed_pkts;
return (error);
}
/*
* Receive a control message.
*/
static int
ng_car_rcvmsg(node_p node, item_p item, hook_p lasthook)
{
const priv_p priv = NG_NODE_PRIVATE(node);
struct ng_mesg *resp = NULL;
int error = 0;
struct ng_mesg *msg;
NGI_GET_MSG(item, msg);
switch (msg->header.typecookie) {
case NGM_CAR_COOKIE:
switch (msg->header.cmd) {
case NGM_CAR_GET_STATS:
case NGM_CAR_GETCLR_STATS:
{
struct ng_car_bulkstats *bstats;
NG_MKRESPONSE(resp, msg,
sizeof(*bstats), M_NOWAIT);
if (resp == NULL) {
error = ENOMEM;
break;
}
bstats = (struct ng_car_bulkstats *)resp->data;
bcopy(&priv->upper.stats, &bstats->downstream,
sizeof(bstats->downstream));
bcopy(&priv->lower.stats, &bstats->upstream,
sizeof(bstats->upstream));
}
if (msg->header.cmd == NGM_CAR_GET_STATS)
break;
case NGM_CAR_CLR_STATS:
bzero(&priv->upper.stats,
sizeof(priv->upper.stats));
bzero(&priv->lower.stats,
sizeof(priv->lower.stats));
break;
case NGM_CAR_GET_CONF:
{
struct ng_car_bulkconf *bconf;
NG_MKRESPONSE(resp, msg,
sizeof(*bconf), M_NOWAIT);
if (resp == NULL) {
error = ENOMEM;
break;
}
bconf = (struct ng_car_bulkconf *)resp->data;
bcopy(&priv->upper.conf, &bconf->downstream,
sizeof(bconf->downstream));
bcopy(&priv->lower.conf, &bconf->upstream,
sizeof(bconf->upstream));
/* Convert internal 1/(8*128) of pps into pps */
if (bconf->downstream.opt & NG_CAR_COUNT_PACKETS) {
bconf->downstream.cir /= 1024;
bconf->downstream.pir /= 1024;
bconf->downstream.cbs /= 128;
bconf->downstream.ebs /= 128;
}
if (bconf->upstream.opt & NG_CAR_COUNT_PACKETS) {
bconf->upstream.cir /= 1024;
bconf->upstream.pir /= 1024;
bconf->upstream.cbs /= 128;
bconf->upstream.ebs /= 128;
}
}
break;
case NGM_CAR_SET_CONF:
{
struct ng_car_bulkconf *const bconf =
(struct ng_car_bulkconf *)msg->data;
/* Check for invalid or illegal config. */
if (msg->header.arglen != sizeof(*bconf)) {
error = EINVAL;
break;
}
/* Convert pps into internal 1/(8*128) of pps */
if (bconf->downstream.opt & NG_CAR_COUNT_PACKETS) {
bconf->downstream.cir *= 1024;
bconf->downstream.pir *= 1024;
bconf->downstream.cbs *= 128;
bconf->downstream.ebs *= 128;
}
if (bconf->upstream.opt & NG_CAR_COUNT_PACKETS) {
bconf->upstream.cir *= 1024;
bconf->upstream.pir *= 1024;
bconf->upstream.cbs *= 128;
bconf->upstream.ebs *= 128;
}
if ((bconf->downstream.cir > 1000000000) ||
(bconf->downstream.pir > 1000000000) ||
(bconf->upstream.cir > 1000000000) ||
(bconf->upstream.pir > 1000000000) ||
(bconf->downstream.cbs == 0 &&
bconf->downstream.ebs == 0) ||
(bconf->upstream.cbs == 0 &&
bconf->upstream.ebs == 0))
{
error = EINVAL;
break;
}
if ((bconf->upstream.mode == NG_CAR_SHAPE) &&
(bconf->upstream.cir == 0)) {
error = EINVAL;
break;
}
if ((bconf->downstream.mode == NG_CAR_SHAPE) &&
(bconf->downstream.cir == 0)) {
error = EINVAL;
break;
}
/* Copy downstream config. */
bcopy(&bconf->downstream, &priv->upper.conf,
sizeof(priv->upper.conf));
priv->upper.tc = priv->upper.conf.cbs;
if (priv->upper.conf.mode == NG_CAR_RED ||
priv->upper.conf.mode == NG_CAR_SHAPE) {
priv->upper.te = 0;
} else {
priv->upper.te = priv->upper.conf.ebs;
}
/* Copy upstream config. */
bcopy(&bconf->upstream, &priv->lower.conf,
sizeof(priv->lower.conf));
priv->lower.tc = priv->lower.conf.cbs;
if (priv->lower.conf.mode == NG_CAR_RED ||
priv->lower.conf.mode == NG_CAR_SHAPE) {
priv->lower.te = 0;
} else {
priv->lower.te = priv->lower.conf.ebs;
}
}
break;
default:
error = EINVAL;
break;
}
break;
default:
error = EINVAL;
break;
}
NG_RESPOND_MSG(error, node, item, resp);
NG_FREE_MSG(msg);
return (error);
}
/*
* Do local shutdown processing.
*/
static int
ng_car_shutdown(node_p node)
{
const priv_p priv = NG_NODE_PRIVATE(node);
ng_uncallout(&priv->upper.q_callout, node);
ng_uncallout(&priv->lower.q_callout, node);
mtx_destroy(&priv->upper.q_mtx);
mtx_destroy(&priv->lower.q_mtx);
NG_NODE_UNREF(priv->node);
free(priv, M_NETGRAPH);
return (0);
}
/*
* Hook disconnection.
*
* For this type, removal of the last link destroys the node.
*/
static int
ng_car_disconnect(hook_p hook)
{
struct hookinfo *const hinfo = NG_HOOK_PRIVATE(hook);
const node_p node = NG_HOOK_NODE(hook);
const priv_p priv = NG_NODE_PRIVATE(node);
if (hinfo) {
/* Purge queue if not empty. */
while (hinfo->q_first != hinfo->q_last) {
NG_FREE_M(hinfo->q[hinfo->q_first]);
hinfo->q_first++;
if (hinfo->q_first >= NG_CAR_QUEUE_SIZE)
hinfo->q_first = 0;
}
/* Remove hook refs. */
if (hinfo->hook == priv->upper.hook)
priv->lower.dest = NULL;
else
priv->upper.dest = NULL;
hinfo->hook = NULL;
}
/* Already shutting down? */
if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
&& (NG_NODE_IS_VALID(NG_HOOK_NODE(hook))))
ng_rmnode_self(NG_HOOK_NODE(hook));
return (0);
}
/*
* Hook's token buckets refillment.
*/
static void
ng_car_refillhook(struct hookinfo *h)
{
struct bintime newt, deltat;
unsigned int deltat_us;
/* Get current time. */
getbinuptime(&newt);
/* Get time delta since last refill. */
deltat = newt;
bintime_sub(&deltat, &h->lastRefill);
/* Time must go forward. */
if (deltat.sec < 0) {
h->lastRefill = newt;
return;
}
/* But not too far forward. */
if (deltat.sec >= 1000) {
deltat_us = (1000 << 20);
} else {
/* convert bintime to the 1/(2^20) of sec */
deltat_us = (deltat.sec << 20) + (deltat.frac >> 44);
}
if (h->conf.mode == NG_CAR_SINGLE_RATE) {
int64_t delta;
/* Refill committed token bucket. */
h->tc += (h->conf.cir * deltat_us) >> 23;
delta = h->tc - h->conf.cbs;
if (delta > 0) {
h->tc = h->conf.cbs;
/* Refill exceeded token bucket. */
h->te += delta;
if (h->te > ((int64_t)h->conf.ebs))
h->te = h->conf.ebs;
}
} else if (h->conf.mode == NG_CAR_DOUBLE_RATE) {
/* Refill committed token bucket. */
h->tc += (h->conf.cir * deltat_us) >> 23;
if (h->tc > ((int64_t)h->conf.cbs))
h->tc = h->conf.cbs;
/* Refill peak token bucket. */
h->te += (h->conf.pir * deltat_us) >> 23;
if (h->te > ((int64_t)h->conf.ebs))
h->te = h->conf.ebs;
} else { /* RED or SHAPE mode. */
/* Refill committed token bucket. */
h->tc += (h->conf.cir * deltat_us) >> 23;
if (h->tc > ((int64_t)h->conf.cbs))
h->tc = h->conf.cbs;
}
/* Remember this moment. */
h->lastRefill = newt;
}
/*
* Schedule callout when we will have required tokens.
*/
static void
ng_car_schedule(struct hookinfo *hinfo)
{
int delay;
delay = (-(hinfo->tc)) * hz * 8 / hinfo->conf.cir + 1;
ng_callout(&hinfo->q_callout, NG_HOOK_NODE(hinfo->hook), hinfo->hook,
delay, &ng_car_q_event, NULL, 0);
}
/*
* Queue processing callout handler.
*/
void
ng_car_q_event(node_p node, hook_p hook, void *arg, int arg2)
{
struct hookinfo *hinfo = NG_HOOK_PRIVATE(hook);
struct mbuf *m;
int error;
/* Refill tokens for time we have slept. */
ng_car_refillhook(hinfo);
/* If we have some tokens */
while (hinfo->tc >= 0) {
/* Send packet. */
m = hinfo->q[hinfo->q_first];
NG_SEND_DATA_ONLY(error, hinfo->dest, m);
if (error != 0)
++hinfo->stats.errors;
++hinfo->stats.passed_pkts;
/* Get next one. */
hinfo->q_first++;
if (hinfo->q_first >= NG_CAR_QUEUE_SIZE)
hinfo->q_first = 0;
/* Stop if none left. */
if (hinfo->q_first == hinfo->q_last)
break;
/* If we have more packet, try it. */
m = hinfo->q[hinfo->q_first];
if (hinfo->conf.opt & NG_CAR_COUNT_PACKETS) {
hinfo->tc -= 128;
} else {
hinfo->tc -= m->m_pkthdr.len;
}
}
/* If something left */
if (hinfo->q_first != hinfo->q_last)
/* Schedule queue processing. */
ng_car_schedule(hinfo);
}
/*
* Enqueue packet.
*/
static void
ng_car_enqueue(struct hookinfo *hinfo, item_p item)
{
struct mbuf *m;
int len;
struct m_qos_color *colp;
enum qos_color col;
NGI_GET_M(item, m);
NG_FREE_ITEM(item);
/* Determine current color of the packet (default green) */
colp = (void *)m_tag_locate(m, M_QOS_COOKIE, M_QOS_COLOR, NULL);
if ((hinfo->conf.opt & NG_CAR_COLOR_AWARE) && (colp != NULL))
col = colp->color;
else
col = QOS_COLOR_GREEN;
/* Lock queue mutex. */
mtx_lock(&hinfo->q_mtx);
/* Calculate used queue length. */
len = hinfo->q_last - hinfo->q_first;
if (len < 0)
len += NG_CAR_QUEUE_SIZE;
/* If queue is overflowed or we have no RED tokens. */
if ((len >= (NG_CAR_QUEUE_SIZE - 1)) ||
(hinfo->te + len >= NG_CAR_QUEUE_SIZE) ||
(col >= QOS_COLOR_RED)) {
/* Drop packet. */
++hinfo->stats.red_pkts;
++hinfo->stats.dropped_pkts;
NG_FREE_M(m);
hinfo->te = 0;
} else {
/* This packet is yellow. */
++hinfo->stats.yellow_pkts;
/* Enqueue packet. */
hinfo->q[hinfo->q_last] = m;
hinfo->q_last++;
if (hinfo->q_last >= NG_CAR_QUEUE_SIZE)
hinfo->q_last = 0;
/* Use RED tokens. */
if (len > NG_CAR_QUEUE_MIN_TH)
hinfo->te += len - NG_CAR_QUEUE_MIN_TH;
/* If this is a first packet in the queue. */
if (len == 0) {
if (hinfo->conf.opt & NG_CAR_COUNT_PACKETS) {
hinfo->tc -= 128;
} else {
hinfo->tc -= m->m_pkthdr.len;
}
/* Schedule queue processing. */
ng_car_schedule(hinfo);
}
}
/* Unlock queue mutex. */
mtx_unlock(&hinfo->q_mtx);
}
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