linux/net/sched/police.c
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

613 lines
13 KiB
C

/*
* net/sched/police.c Input police filter.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
* J Hadi Salim (action changes)
*/
#include <asm/uaccess.h>
#include <asm/system.h>
#include <linux/bitops.h>
#include <linux/config.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/in.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/module.h>
#include <linux/rtnetlink.h>
#include <linux/init.h>
#include <net/sock.h>
#include <net/act_api.h>
#define L2T(p,L) ((p)->R_tab->data[(L)>>(p)->R_tab->rate.cell_log])
#define L2T_P(p,L) ((p)->P_tab->data[(L)>>(p)->P_tab->rate.cell_log])
#define PRIV(a) ((struct tcf_police *) (a)->priv)
/* use generic hash table */
#define MY_TAB_SIZE 16
#define MY_TAB_MASK 15
static u32 idx_gen;
static struct tcf_police *tcf_police_ht[MY_TAB_SIZE];
/* Policer hash table lock */
static DEFINE_RWLOCK(police_lock);
/* Each policer is serialized by its individual spinlock */
static __inline__ unsigned tcf_police_hash(u32 index)
{
return index&0xF;
}
static __inline__ struct tcf_police * tcf_police_lookup(u32 index)
{
struct tcf_police *p;
read_lock(&police_lock);
for (p = tcf_police_ht[tcf_police_hash(index)]; p; p = p->next) {
if (p->index == index)
break;
}
read_unlock(&police_lock);
return p;
}
#ifdef CONFIG_NET_CLS_ACT
static int tcf_generic_walker(struct sk_buff *skb, struct netlink_callback *cb,
int type, struct tc_action *a)
{
struct tcf_police *p;
int err = 0, index = -1, i = 0, s_i = 0, n_i = 0;
struct rtattr *r;
read_lock(&police_lock);
s_i = cb->args[0];
for (i = 0; i < MY_TAB_SIZE; i++) {
p = tcf_police_ht[tcf_police_hash(i)];
for (; p; p = p->next) {
index++;
if (index < s_i)
continue;
a->priv = p;
a->order = index;
r = (struct rtattr*) skb->tail;
RTA_PUT(skb, a->order, 0, NULL);
if (type == RTM_DELACTION)
err = tcf_action_dump_1(skb, a, 0, 1);
else
err = tcf_action_dump_1(skb, a, 0, 0);
if (err < 0) {
index--;
skb_trim(skb, (u8*)r - skb->data);
goto done;
}
r->rta_len = skb->tail - (u8*)r;
n_i++;
}
}
done:
read_unlock(&police_lock);
if (n_i)
cb->args[0] += n_i;
return n_i;
rtattr_failure:
skb_trim(skb, (u8*)r - skb->data);
goto done;
}
static inline int
tcf_hash_search(struct tc_action *a, u32 index)
{
struct tcf_police *p = tcf_police_lookup(index);
if (p != NULL) {
a->priv = p;
return 1;
} else {
return 0;
}
}
#endif
static inline u32 tcf_police_new_index(void)
{
do {
if (++idx_gen == 0)
idx_gen = 1;
} while (tcf_police_lookup(idx_gen));
return idx_gen;
}
void tcf_police_destroy(struct tcf_police *p)
{
unsigned h = tcf_police_hash(p->index);
struct tcf_police **p1p;
for (p1p = &tcf_police_ht[h]; *p1p; p1p = &(*p1p)->next) {
if (*p1p == p) {
write_lock_bh(&police_lock);
*p1p = p->next;
write_unlock_bh(&police_lock);
#ifdef CONFIG_NET_ESTIMATOR
gen_kill_estimator(&p->bstats, &p->rate_est);
#endif
if (p->R_tab)
qdisc_put_rtab(p->R_tab);
if (p->P_tab)
qdisc_put_rtab(p->P_tab);
kfree(p);
return;
}
}
BUG_TRAP(0);
}
#ifdef CONFIG_NET_CLS_ACT
static int tcf_act_police_locate(struct rtattr *rta, struct rtattr *est,
struct tc_action *a, int ovr, int bind)
{
unsigned h;
int ret = 0, err;
struct rtattr *tb[TCA_POLICE_MAX];
struct tc_police *parm;
struct tcf_police *p;
struct qdisc_rate_table *R_tab = NULL, *P_tab = NULL;
if (rta == NULL || rtattr_parse_nested(tb, TCA_POLICE_MAX, rta) < 0)
return -EINVAL;
if (tb[TCA_POLICE_TBF-1] == NULL ||
RTA_PAYLOAD(tb[TCA_POLICE_TBF-1]) != sizeof(*parm))
return -EINVAL;
parm = RTA_DATA(tb[TCA_POLICE_TBF-1]);
if (tb[TCA_POLICE_RESULT-1] != NULL &&
RTA_PAYLOAD(tb[TCA_POLICE_RESULT-1]) != sizeof(u32))
return -EINVAL;
if (tb[TCA_POLICE_RESULT-1] != NULL &&
RTA_PAYLOAD(tb[TCA_POLICE_RESULT-1]) != sizeof(u32))
return -EINVAL;
if (parm->index && (p = tcf_police_lookup(parm->index)) != NULL) {
a->priv = p;
if (bind) {
p->bindcnt += 1;
p->refcnt += 1;
}
if (ovr)
goto override;
return ret;
}
p = kmalloc(sizeof(*p), GFP_KERNEL);
if (p == NULL)
return -ENOMEM;
memset(p, 0, sizeof(*p));
ret = ACT_P_CREATED;
p->refcnt = 1;
spin_lock_init(&p->lock);
p->stats_lock = &p->lock;
if (bind)
p->bindcnt = 1;
override:
if (parm->rate.rate) {
err = -ENOMEM;
R_tab = qdisc_get_rtab(&parm->rate, tb[TCA_POLICE_RATE-1]);
if (R_tab == NULL)
goto failure;
if (parm->peakrate.rate) {
P_tab = qdisc_get_rtab(&parm->peakrate,
tb[TCA_POLICE_PEAKRATE-1]);
if (p->P_tab == NULL) {
qdisc_put_rtab(R_tab);
goto failure;
}
}
}
/* No failure allowed after this point */
spin_lock_bh(&p->lock);
if (R_tab != NULL) {
qdisc_put_rtab(p->R_tab);
p->R_tab = R_tab;
}
if (P_tab != NULL) {
qdisc_put_rtab(p->P_tab);
p->P_tab = P_tab;
}
if (tb[TCA_POLICE_RESULT-1])
p->result = *(u32*)RTA_DATA(tb[TCA_POLICE_RESULT-1]);
p->toks = p->burst = parm->burst;
p->mtu = parm->mtu;
if (p->mtu == 0) {
p->mtu = ~0;
if (p->R_tab)
p->mtu = 255<<p->R_tab->rate.cell_log;
}
if (p->P_tab)
p->ptoks = L2T_P(p, p->mtu);
p->action = parm->action;
#ifdef CONFIG_NET_ESTIMATOR
if (tb[TCA_POLICE_AVRATE-1])
p->ewma_rate = *(u32*)RTA_DATA(tb[TCA_POLICE_AVRATE-1]);
if (est)
gen_replace_estimator(&p->bstats, &p->rate_est, p->stats_lock, est);
#endif
spin_unlock_bh(&p->lock);
if (ret != ACT_P_CREATED)
return ret;
PSCHED_GET_TIME(p->t_c);
p->index = parm->index ? : tcf_police_new_index();
h = tcf_police_hash(p->index);
write_lock_bh(&police_lock);
p->next = tcf_police_ht[h];
tcf_police_ht[h] = p;
write_unlock_bh(&police_lock);
a->priv = p;
return ret;
failure:
if (ret == ACT_P_CREATED)
kfree(p);
return err;
}
static int tcf_act_police_cleanup(struct tc_action *a, int bind)
{
struct tcf_police *p = PRIV(a);
if (p != NULL)
return tcf_police_release(p, bind);
return 0;
}
static int tcf_act_police(struct sk_buff **pskb, struct tc_action *a)
{
psched_time_t now;
struct sk_buff *skb = *pskb;
struct tcf_police *p = PRIV(a);
long toks;
long ptoks = 0;
spin_lock(&p->lock);
p->bstats.bytes += skb->len;
p->bstats.packets++;
#ifdef CONFIG_NET_ESTIMATOR
if (p->ewma_rate && p->rate_est.bps >= p->ewma_rate) {
p->qstats.overlimits++;
spin_unlock(&p->lock);
return p->action;
}
#endif
if (skb->len <= p->mtu) {
if (p->R_tab == NULL) {
spin_unlock(&p->lock);
return p->result;
}
PSCHED_GET_TIME(now);
toks = PSCHED_TDIFF_SAFE(now, p->t_c, p->burst);
if (p->P_tab) {
ptoks = toks + p->ptoks;
if (ptoks > (long)L2T_P(p, p->mtu))
ptoks = (long)L2T_P(p, p->mtu);
ptoks -= L2T_P(p, skb->len);
}
toks += p->toks;
if (toks > (long)p->burst)
toks = p->burst;
toks -= L2T(p, skb->len);
if ((toks|ptoks) >= 0) {
p->t_c = now;
p->toks = toks;
p->ptoks = ptoks;
spin_unlock(&p->lock);
return p->result;
}
}
p->qstats.overlimits++;
spin_unlock(&p->lock);
return p->action;
}
static int
tcf_act_police_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
{
unsigned char *b = skb->tail;
struct tc_police opt;
struct tcf_police *p = PRIV(a);
opt.index = p->index;
opt.action = p->action;
opt.mtu = p->mtu;
opt.burst = p->burst;
opt.refcnt = p->refcnt - ref;
opt.bindcnt = p->bindcnt - bind;
if (p->R_tab)
opt.rate = p->R_tab->rate;
else
memset(&opt.rate, 0, sizeof(opt.rate));
if (p->P_tab)
opt.peakrate = p->P_tab->rate;
else
memset(&opt.peakrate, 0, sizeof(opt.peakrate));
RTA_PUT(skb, TCA_POLICE_TBF, sizeof(opt), &opt);
if (p->result)
RTA_PUT(skb, TCA_POLICE_RESULT, sizeof(int), &p->result);
#ifdef CONFIG_NET_ESTIMATOR
if (p->ewma_rate)
RTA_PUT(skb, TCA_POLICE_AVRATE, 4, &p->ewma_rate);
#endif
return skb->len;
rtattr_failure:
skb_trim(skb, b - skb->data);
return -1;
}
MODULE_AUTHOR("Alexey Kuznetsov");
MODULE_DESCRIPTION("Policing actions");
MODULE_LICENSE("GPL");
static struct tc_action_ops act_police_ops = {
.kind = "police",
.type = TCA_ID_POLICE,
.capab = TCA_CAP_NONE,
.owner = THIS_MODULE,
.act = tcf_act_police,
.dump = tcf_act_police_dump,
.cleanup = tcf_act_police_cleanup,
.lookup = tcf_hash_search,
.init = tcf_act_police_locate,
.walk = tcf_generic_walker
};
static int __init
police_init_module(void)
{
return tcf_register_action(&act_police_ops);
}
static void __exit
police_cleanup_module(void)
{
tcf_unregister_action(&act_police_ops);
}
module_init(police_init_module);
module_exit(police_cleanup_module);
#endif
struct tcf_police * tcf_police_locate(struct rtattr *rta, struct rtattr *est)
{
unsigned h;
struct tcf_police *p;
struct rtattr *tb[TCA_POLICE_MAX];
struct tc_police *parm;
if (rtattr_parse_nested(tb, TCA_POLICE_MAX, rta) < 0)
return NULL;
if (tb[TCA_POLICE_TBF-1] == NULL ||
RTA_PAYLOAD(tb[TCA_POLICE_TBF-1]) != sizeof(*parm))
return NULL;
parm = RTA_DATA(tb[TCA_POLICE_TBF-1]);
if (parm->index && (p = tcf_police_lookup(parm->index)) != NULL) {
p->refcnt++;
return p;
}
p = kmalloc(sizeof(*p), GFP_KERNEL);
if (p == NULL)
return NULL;
memset(p, 0, sizeof(*p));
p->refcnt = 1;
spin_lock_init(&p->lock);
p->stats_lock = &p->lock;
if (parm->rate.rate) {
p->R_tab = qdisc_get_rtab(&parm->rate, tb[TCA_POLICE_RATE-1]);
if (p->R_tab == NULL)
goto failure;
if (parm->peakrate.rate) {
p->P_tab = qdisc_get_rtab(&parm->peakrate,
tb[TCA_POLICE_PEAKRATE-1]);
if (p->P_tab == NULL)
goto failure;
}
}
if (tb[TCA_POLICE_RESULT-1]) {
if (RTA_PAYLOAD(tb[TCA_POLICE_RESULT-1]) != sizeof(u32))
goto failure;
p->result = *(u32*)RTA_DATA(tb[TCA_POLICE_RESULT-1]);
}
#ifdef CONFIG_NET_ESTIMATOR
if (tb[TCA_POLICE_AVRATE-1]) {
if (RTA_PAYLOAD(tb[TCA_POLICE_AVRATE-1]) != sizeof(u32))
goto failure;
p->ewma_rate = *(u32*)RTA_DATA(tb[TCA_POLICE_AVRATE-1]);
}
#endif
p->toks = p->burst = parm->burst;
p->mtu = parm->mtu;
if (p->mtu == 0) {
p->mtu = ~0;
if (p->R_tab)
p->mtu = 255<<p->R_tab->rate.cell_log;
}
if (p->P_tab)
p->ptoks = L2T_P(p, p->mtu);
PSCHED_GET_TIME(p->t_c);
p->index = parm->index ? : tcf_police_new_index();
p->action = parm->action;
#ifdef CONFIG_NET_ESTIMATOR
if (est)
gen_new_estimator(&p->bstats, &p->rate_est, p->stats_lock, est);
#endif
h = tcf_police_hash(p->index);
write_lock_bh(&police_lock);
p->next = tcf_police_ht[h];
tcf_police_ht[h] = p;
write_unlock_bh(&police_lock);
return p;
failure:
if (p->R_tab)
qdisc_put_rtab(p->R_tab);
kfree(p);
return NULL;
}
int tcf_police(struct sk_buff *skb, struct tcf_police *p)
{
psched_time_t now;
long toks;
long ptoks = 0;
spin_lock(&p->lock);
p->bstats.bytes += skb->len;
p->bstats.packets++;
#ifdef CONFIG_NET_ESTIMATOR
if (p->ewma_rate && p->rate_est.bps >= p->ewma_rate) {
p->qstats.overlimits++;
spin_unlock(&p->lock);
return p->action;
}
#endif
if (skb->len <= p->mtu) {
if (p->R_tab == NULL) {
spin_unlock(&p->lock);
return p->result;
}
PSCHED_GET_TIME(now);
toks = PSCHED_TDIFF_SAFE(now, p->t_c, p->burst);
if (p->P_tab) {
ptoks = toks + p->ptoks;
if (ptoks > (long)L2T_P(p, p->mtu))
ptoks = (long)L2T_P(p, p->mtu);
ptoks -= L2T_P(p, skb->len);
}
toks += p->toks;
if (toks > (long)p->burst)
toks = p->burst;
toks -= L2T(p, skb->len);
if ((toks|ptoks) >= 0) {
p->t_c = now;
p->toks = toks;
p->ptoks = ptoks;
spin_unlock(&p->lock);
return p->result;
}
}
p->qstats.overlimits++;
spin_unlock(&p->lock);
return p->action;
}
int tcf_police_dump(struct sk_buff *skb, struct tcf_police *p)
{
unsigned char *b = skb->tail;
struct tc_police opt;
opt.index = p->index;
opt.action = p->action;
opt.mtu = p->mtu;
opt.burst = p->burst;
if (p->R_tab)
opt.rate = p->R_tab->rate;
else
memset(&opt.rate, 0, sizeof(opt.rate));
if (p->P_tab)
opt.peakrate = p->P_tab->rate;
else
memset(&opt.peakrate, 0, sizeof(opt.peakrate));
RTA_PUT(skb, TCA_POLICE_TBF, sizeof(opt), &opt);
if (p->result)
RTA_PUT(skb, TCA_POLICE_RESULT, sizeof(int), &p->result);
#ifdef CONFIG_NET_ESTIMATOR
if (p->ewma_rate)
RTA_PUT(skb, TCA_POLICE_AVRATE, 4, &p->ewma_rate);
#endif
return skb->len;
rtattr_failure:
skb_trim(skb, b - skb->data);
return -1;
}
int tcf_police_dump_stats(struct sk_buff *skb, struct tcf_police *p)
{
struct gnet_dump d;
if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS,
TCA_XSTATS, p->stats_lock, &d) < 0)
goto errout;
if (gnet_stats_copy_basic(&d, &p->bstats) < 0 ||
#ifdef CONFIG_NET_ESTIMATOR
gnet_stats_copy_rate_est(&d, &p->rate_est) < 0 ||
#endif
gnet_stats_copy_queue(&d, &p->qstats) < 0)
goto errout;
if (gnet_stats_finish_copy(&d) < 0)
goto errout;
return 0;
errout:
return -1;
}
EXPORT_SYMBOL(tcf_police);
EXPORT_SYMBOL(tcf_police_destroy);
EXPORT_SYMBOL(tcf_police_dump);
EXPORT_SYMBOL(tcf_police_dump_stats);
EXPORT_SYMBOL(tcf_police_hash);
EXPORT_SYMBOL(tcf_police_ht);
EXPORT_SYMBOL(tcf_police_locate);
EXPORT_SYMBOL(tcf_police_lookup);
EXPORT_SYMBOL(tcf_police_new_index);