/* * 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> */#include <asm/uaccess.h>#include <asm/system.h>#include <asm/bitops.h>#include <linux/config.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/rtnetlink.h>#include <linux/init.h>#include <linux/proc_fs.h>#include <net/sock.h>#include <net/pkt_sched.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])static u32 idx_gen;static struct tcf_police *tcf_police_ht[16];/* Policer hash table lock */static rwlock_t police_lock = RW_LOCK_UNLOCKED;/* 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;}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			qdisc_kill_estimator(&p->stats);#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);}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(tb, TCA_POLICE_MAX, RTA_DATA(rta), RTA_PAYLOAD(rta)) < 0)		return NULL;	if (tb[TCA_POLICE_TBF-1] == NULL)		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) {		if ((p->R_tab = qdisc_get_rtab(&parm->rate, tb[TCA_POLICE_RATE-1])) == NULL)			goto failure;		if (parm->peakrate.rate &&		    (p->P_tab = qdisc_get_rtab(&parm->peakrate, tb[TCA_POLICE_PEAKRATE-1])) == NULL)			goto failure;	}	if (tb[TCA_POLICE_RESULT-1])		p->result = *(int*)RTA_DATA(tb[TCA_POLICE_RESULT-1]);#ifdef CONFIG_NET_ESTIMATOR	if (tb[TCA_POLICE_AVRATE-1])		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)		qdisc_new_estimator(&p->stats, 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->stats.bytes += skb->len;	p->stats.packets++;#ifdef CONFIG_NET_ESTIMATOR	if (p->ewma_rate && p->stats.bps >= p->ewma_rate) {		p->stats.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, 0);		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->stats.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;}