Add esfq to iproute2 and 2.4 kernel (#1891)

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@7612 3c298f89-4303-0410-b956-a3cf2f4a3e73

1 files changed, 747 insertions, 0 deletions

diff --git a/target/linux/generic-2.4/patches/620-tc_esfq.patch b/target/linux/generic-2.4/patches/620-tc_esfq.patch
new file mode 100644
index 000000000..d342042c4
--- /dev/null
+++ b/target/linux/generic-2.4/patches/620-tc_esfq.patch
@@ -0,0 +1,747 @@
+diff -urN target.old/linux/generic-2.4/patches/232-esfq_kmod.patch target/linux/generic-2.4/patches/232-esfq_kmod.patch
+--- target.old/linux/generic-2.4/patches/232-esfq_kmod.patch	1969-12-31 19:00:00.000000000 -0500
++++ target/linux/generic-2.4/patches/232-esfq_kmod.patch	2007-06-08 02:35:06.000000000 -0400
+@@ -0,0 +1,743 @@
++diff -urN linux-2.4.34/Documentation/Configure.help linux-2.4.34/Documentation/Configure.help
++--- linux-2.4.34/Documentation/Configure.help	2007-05-10 19:37:42.000000000 -0400
+++++ linux-2.4.34/Documentation/Configure.help	2007-05-10 19:49:49.000000000 -0400
++@@ -11127,6 +11127,24 @@
++   whenever you want).  If you want to compile it as a module, say M
++   here and read <file:Documentation/modules.txt>.
++ 
+++ESFQ queue
+++CONFIG_NET_SCH_ESFQ
+++  Say Y here if you want to use the Stochastic Fairness Queueing (SFQ)
+++  packet scheduling algorithm for some of your network devices or as a
+++  leaf discipline for the CBQ scheduling algorithm (see the top of
+++  <file:net/sched/sch_esfq.c> for details and references about the SFQ
+++  algorithm).
+++
+++  This is an enchanced SFQ version which allows you to control the
+++  hardcoded values in the SFQ scheduler: queue depth, hash table size,
+++  queues limit. Also adds control to the hash function used to identify
+++  packet flows. Hash by src or dst ip and original sfq hash.
+++
+++  This code is also available as a module called sch_esfq.o ( = code
+++  which can be inserted in and removed from the running kernel
+++  whenever you want). If you want to compile it as a module, say M
+++  here and read <file:Documentation/modules.txt>.
+++
++ CSZ packet scheduler
++ CONFIG_NET_SCH_CSZ
++   Say Y here if you want to use the Clark-Shenker-Zhang (CSZ) packet
++diff -urN linux-2.4.34/include/linux/pkt_sched.h linux-2.4.34/include/linux/pkt_sched.h
++--- linux-2.4.34/include/linux/pkt_sched.h	2007-05-10 19:38:19.000000000 -0400
+++++ linux-2.4.34/include/linux/pkt_sched.h	2007-05-10 19:53:59.000000000 -0400
++@@ -173,8 +173,36 @@
++  *
++  *	The only reason for this is efficiency, it is possible
++  *	to change these parameters in compile time.
+++ *
+++ *	If you need to play with these values use esfq instead.
++  */
++ 
+++/* ESFQ section */
+++
+++enum
+++{
+++	/* traditional */
+++	TCA_SFQ_HASH_CLASSIC,
+++	TCA_SFQ_HASH_DST,
+++	TCA_SFQ_HASH_SRC,
+++	/* conntrack */
+++	TCA_SFQ_HASH_CTORIGDST,
+++	TCA_SFQ_HASH_CTORIGSRC,
+++	TCA_SFQ_HASH_CTREPLDST,
+++	TCA_SFQ_HASH_CTREPLSRC,
+++	TCA_SFQ_HASH_CTNATCHG,
+++};
+++
+++struct tc_esfq_qopt
+++{
+++	unsigned	quantum;	/* Bytes per round allocated to flow */
+++	int		perturb_period; /* Period of hash perturbation */
+++	__u32		limit;		/* Maximal packets in queue */
+++	unsigned	divisor;	/* Hash divisor  */
+++	unsigned	flows;		/* Maximal number of flows  */
+++	unsigned	hash_kind;	/* Hash function to use for flow identification */
+++};
+++
++ /* RED section */
++ 
++ enum
++diff -urN linux-2.4.34/net/sched/Config.in linux-2.4.34/net/sched/Config.in
++--- linux-2.4.34/net/sched/Config.in	2007-05-10 19:38:31.000000000 -0400
+++++ linux-2.4.34/net/sched/Config.in	2007-05-10 19:54:45.000000000 -0400
++@@ -12,6 +12,7 @@
++ tristate '  The simplest PRIO pseudoscheduler' CONFIG_NET_SCH_PRIO
++ tristate '  RED queue' CONFIG_NET_SCH_RED
++ tristate '  SFQ queue' CONFIG_NET_SCH_SFQ
+++tristate '  ESFQ queue' CONFIG_NET_SCH_ESFQ
++ tristate '  TEQL queue' CONFIG_NET_SCH_TEQL
++ tristate '  TBF queue' CONFIG_NET_SCH_TBF
++ tristate '  GRED queue' CONFIG_NET_SCH_GRED
++diff -urN linux-2.4.34/net/sched/Makefile linux-2.4.34/net/sched/Makefile
++--- linux-2.4.34/net/sched/Makefile	2007-05-10 19:38:31.000000000 -0400
+++++ linux-2.4.34/net/sched/Makefile	2007-05-10 19:55:13.000000000 -0400
++@@ -19,6 +19,7 @@
++ obj-$(CONFIG_NET_SCH_HFSC)	+= sch_hfsc.o
++ obj-$(CONFIG_NET_SCH_HTB)	+= sch_htb.o
++ obj-$(CONFIG_NET_SCH_SFQ)	+= sch_sfq.o
+++obj-$(CONFIG_NET_SCH_ESFQ)	+= sch_esfq.o
++ obj-$(CONFIG_NET_SCH_RED)	+= sch_red.o
++ obj-$(CONFIG_NET_SCH_TBF)	+= sch_tbf.o
++ obj-$(CONFIG_NET_SCH_PRIO)	+= sch_prio.o
++diff -urN linux-2.4.34/net/sched/sch_esfq.c linux-2.4.34/net/sched/sch_esfq.c
++--- linux-2.4.34/net/sched/sch_esfq.c	1969-12-31 19:00:00.000000000 -0500
+++++ linux-2.4.34/net/sched/sch_esfq.c	2007-05-10 19:57:15.000000000 -0400
++@@ -0,0 +1,649 @@
+++/*
+++ * net/sched/sch_esfq.c	Extended Stochastic Fairness Queueing discipline.
+++ *
+++ *		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>
+++ *
+++ * Changes:	Alexander Atanasov, <alex@ssi.bg>
+++ *		Added dynamic depth,limit,divisor,hash_kind options.
+++ *		Added dst and src hashes.
+++ *
+++ * 		Alexander Clouter, <alex@digriz.org.uk>
+++ *		Ported ESFQ to Linux 2.6.
+++ *
+++ * 		Corey Hickey, <bugfood-c@fatooh.org>
+++ *		Maintenance of the Linux 2.6 port.
+++ *		Added fwmark hash (thanks to Robert Kurjata).
+++ *		Added usage of jhash.
+++ *		
+++ */
+++
+++#include <linux/config.h>
+++#include <linux/module.h>
+++#include <asm/uaccess.h>
+++#include <asm/system.h>
+++#include <linux/bitops.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/if_ether.h>
+++#include <linux/inet.h>
+++#include <linux/netdevice.h>
+++#include <linux/etherdevice.h>
+++#include <linux/notifier.h>
+++#include <linux/init.h>
+++#include <net/ip.h>
+++#include <net/route.h>
+++#include <linux/skbuff.h>
+++#include <net/sock.h>
+++#include <net/pkt_sched.h>
+++#include <linux/jhash.h>
+++
+++#define IPPROTO_DCCP 33
+++#define qdisc_priv(q)   ((void *)(q->data))
+++
+++#ifdef CONFIG_IP_NF_CONNTRACK
+++/* #include <net/netfilter/nf_conntrack.h> */
+++#include <linux/netfilter_ipv4/ip_conntrack.h>
+++#endif
+++
+++/*	Stochastic Fairness Queuing algorithm.
+++	For more comments look at sch_sfq.c.
+++	The difference is that you can change limit, depth,
+++	hash table size and choose alternate hash types.
+++	
+++	classic:	same as in sch_sfq.c
+++	dst:		destination IP address
+++	src:		source IP address
+++	ctorigdst:	original destination IP address
+++	ctorigsrc:	original source IP address
+++	ctrepldst:	reply destination IP address
+++	ctreplsrc:	reply source IP 
+++	ctnatchg:	use the address which changed via nat
+++	
+++*/
+++
+++
+++/* This type should contain at least SFQ_DEPTH*2 values */
+++typedef unsigned int esfq_index;
+++
+++struct esfq_head
+++{
+++	esfq_index	next;
+++	esfq_index	prev;
+++};
+++
+++struct esfq_sched_data
+++{
+++/* Parameters */
+++	int		perturb_period;
+++	unsigned	quantum;	/* Allotment per round: MUST BE >= MTU */
+++	int		limit;
+++	unsigned	depth;
+++	unsigned	hash_divisor;
+++	unsigned	hash_kind;
+++/* Variables */
+++	struct timer_list perturb_timer;
+++	int		perturbation;
+++	esfq_index	tail;		/* Index of current slot in round */
+++	esfq_index	max_depth;	/* Maximal depth */
+++
+++	esfq_index	*ht;			/* Hash table */
+++	esfq_index	*next;			/* Active slots link */
+++	short		*allot;			/* Current allotment per slot */
+++	unsigned short	*hash;			/* Hash value indexed by slots */
+++	struct sk_buff_head	*qs;		/* Slot queue */
+++	struct esfq_head	*dep;		/* Linked list of slots, indexed by depth */
+++	unsigned	dyn_min;	/* For dynamic divisor adjustment; minimum value seen */
+++	unsigned	dyn_max;	/*                                 maximum value seen */
+++	unsigned	dyn_range;	/*	        		   saved range */
+++};
+++
+++/* This contains the info we will hash. */
+++struct esfq_packet_info
+++{
+++	u32	proto;		/* protocol or port */
+++	u32	src;		/* source from packet header */
+++	u32	dst;		/* destination from packet header */
+++	u32	ctorigsrc;	/* original source from conntrack */
+++	u32	ctorigdst;	/* original destination from conntrack */
+++	u32	ctreplsrc;	/* reply source from conntrack */
+++	u32	ctrepldst;	/* reply destination from conntrack */
+++};
+++
+++static __inline__ unsigned esfq_jhash_1word(struct esfq_sched_data *q,u32 a)
+++{
+++	return jhash_1word(a, q->perturbation) & (q->hash_divisor-1);
+++}
+++
+++static __inline__ unsigned esfq_jhash_2words(struct esfq_sched_data *q, u32 a, u32 b)
+++{
+++	return jhash_2words(a, b, q->perturbation) & (q->hash_divisor-1);
+++}
+++
+++static __inline__ unsigned esfq_jhash_3words(struct esfq_sched_data *q, u32 a, u32 b, u32 c)
+++{
+++	return jhash_3words(a, b, c, q->perturbation) & (q->hash_divisor-1);
+++}
+++
+++
+++static unsigned esfq_hash(struct esfq_sched_data *q, struct sk_buff *skb)
+++{
+++	struct esfq_packet_info info;
+++#ifdef CONFIG_IP_NF_CONNTRACK
+++	enum ip_conntrack_info ctinfo;
+++	struct ip_conntrack *ct = ip_conntrack_get(skb, &ctinfo);
+++#endif
+++	
+++	switch (skb->protocol) {
+++	case __constant_htons(ETH_P_IP):
+++	{
+++		struct iphdr *iph = skb->nh.iph;
+++		info.dst = iph->daddr;
+++		info.src = iph->saddr;
+++		if (!(iph->frag_off&htons(IP_MF|IP_OFFSET)) &&
+++		    (iph->protocol == IPPROTO_TCP ||
+++		     iph->protocol == IPPROTO_UDP ||
+++		     iph->protocol == IPPROTO_SCTP ||
+++		     iph->protocol == IPPROTO_DCCP ||
+++		     iph->protocol == IPPROTO_ESP))
+++			info.proto = *(((u32*)iph) + iph->ihl);
+++		else
+++			info.proto = iph->protocol;
+++		break;
+++	}
+++	default:
+++		info.dst   = (u32)(unsigned long)skb->dst;
+++		info.src   = (u32)(unsigned long)skb->sk;
+++		info.proto = skb->protocol;
+++	}
+++
+++#ifdef CONFIG_IP_NF_CONNTRACK
+++	/* defaults if there is no conntrack info */
+++	info.ctorigsrc = info.src;
+++	info.ctorigdst = info.dst;
+++	info.ctreplsrc = info.dst;
+++	info.ctrepldst = info.src;
+++	/* collect conntrack info */
+++	IP_NF_ASSERT(ct);
+++	if (ct) {
+++		if (skb->protocol == __constant_htons(ETH_P_IP)) {
+++			info.ctorigsrc = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.ip;
+++			info.ctorigdst = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.ip;
+++			info.ctreplsrc = ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.ip;
+++			info.ctrepldst = ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.ip;
+++		}
+++	}
+++#endif
+++
+++	switch(q->hash_kind)
+++	{
+++	case TCA_SFQ_HASH_CLASSIC:
+++		return esfq_jhash_3words(q, info.dst, info.src, info.proto);
+++	case TCA_SFQ_HASH_DST:
+++		return esfq_jhash_1word(q, info.dst);
+++	case TCA_SFQ_HASH_SRC:
+++		return esfq_jhash_1word(q, info.src);
+++#ifdef CONFIG_IP_NF_CONNTRACK
+++	case TCA_SFQ_HASH_CTORIGDST:
+++		return esfq_jhash_1word(q, info.ctorigdst);
+++	case TCA_SFQ_HASH_CTORIGSRC:
+++		return esfq_jhash_1word(q, info.ctorigsrc);
+++	case TCA_SFQ_HASH_CTREPLDST:
+++		return esfq_jhash_1word(q, info.ctrepldst);
+++	case TCA_SFQ_HASH_CTREPLSRC:
+++		return esfq_jhash_1word(q, info.ctreplsrc);
+++	case TCA_SFQ_HASH_CTNATCHG:
+++	{
+++		if (info.ctorigdst == info.ctreplsrc)
+++			return esfq_jhash_1word(q, info.ctorigsrc);
+++		else
+++			return esfq_jhash_1word(q, info.ctreplsrc);
+++	}
+++#endif
+++	default:
+++		if (net_ratelimit())
+++			printk(KERN_WARNING "ESFQ: Unknown hash method. Falling back to classic.\n");
+++	}
+++	return esfq_jhash_3words(q, info.dst, info.src, info.proto);
+++}
+++
+++static inline void esfq_link(struct esfq_sched_data *q, esfq_index x)
+++{
+++	esfq_index p, n;
+++	int d = q->qs[x].qlen + q->depth;
+++
+++	p = d;
+++	n = q->dep[d].next;
+++	q->dep[x].next = n;
+++	q->dep[x].prev = p;
+++	q->dep[p].next = q->dep[n].prev = x;
+++}
+++
+++static inline void esfq_dec(struct esfq_sched_data *q, esfq_index x)
+++{
+++	esfq_index p, n;
+++
+++	n = q->dep[x].next;
+++	p = q->dep[x].prev;
+++	q->dep[p].next = n;
+++	q->dep[n].prev = p;
+++
+++	if (n == p && q->max_depth == q->qs[x].qlen + 1)
+++		q->max_depth--;
+++
+++	esfq_link(q, x);
+++}
+++
+++static inline void esfq_inc(struct esfq_sched_data *q, esfq_index x)
+++{
+++	esfq_index p, n;
+++	int d;
+++
+++	n = q->dep[x].next;
+++	p = q->dep[x].prev;
+++	q->dep[p].next = n;
+++	q->dep[n].prev = p;
+++	d = q->qs[x].qlen;
+++	if (q->max_depth < d)
+++		q->max_depth = d;
+++
+++	esfq_link(q, x);
+++}
+++
+++static unsigned int esfq_drop(struct Qdisc *sch)
+++{
+++	struct esfq_sched_data *q = qdisc_priv(sch);
+++	esfq_index d = q->max_depth;
+++	struct sk_buff *skb;
+++	unsigned int len;
+++
+++	/* Queue is full! Find the longest slot and
+++	   drop a packet from it */
+++
+++	if (d > 1) {
+++		esfq_index x = q->dep[d+q->depth].next;
+++		skb = q->qs[x].prev;
+++		len = skb->len;
+++		__skb_unlink(skb, &q->qs[x]);
+++		kfree_skb(skb);
+++		esfq_dec(q, x);
+++		sch->q.qlen--;
+++		sch->stats.drops++;
+++		sch->stats.backlog -= len;
+++		return len;
+++	}
+++
+++	if (d == 1) {
+++		/* It is difficult to believe, but ALL THE SLOTS HAVE LENGTH 1. */
+++		d = q->next[q->tail];
+++		q->next[q->tail] = q->next[d];
+++		q->allot[q->next[d]] += q->quantum;
+++		skb = q->qs[d].prev;
+++		len = skb->len;
+++		__skb_unlink(skb, &q->qs[d]);
+++		kfree_skb(skb);
+++		esfq_dec(q, d);
+++		sch->q.qlen--;
+++		q->ht[q->hash[d]] = q->depth;
+++		sch->stats.drops++;
+++		sch->stats.backlog -= len;
+++		return len;
+++	}
+++
+++	return 0;
+++}
+++
+++static int
+++esfq_enqueue(struct sk_buff *skb, struct Qdisc* sch)
+++{
+++	struct esfq_sched_data *q = qdisc_priv(sch);
+++	unsigned hash = esfq_hash(q, skb);
+++	unsigned depth = q->depth;
+++	esfq_index x;
+++
+++	x = q->ht[hash];
+++	if (x == depth) {
+++		q->ht[hash] = x = q->dep[depth].next;
+++		q->hash[x] = hash;
+++	}
+++	sch->stats.backlog += skb->len;
+++	__skb_queue_tail(&q->qs[x], skb);
+++	esfq_inc(q, x);
+++	if (q->qs[x].qlen == 1) {		/* The flow is new */
+++		if (q->tail == depth) {	/* It is the first flow */
+++			q->tail = x;
+++			q->next[x] = x;
+++			q->allot[x] = q->quantum;
+++		} else {
+++			q->next[x] = q->next[q->tail];
+++			q->next[q->tail] = x;
+++			q->tail = x;
+++		}
+++	}
+++	if (++sch->q.qlen < q->limit-1) {
+++		sch->stats.bytes += skb->len;
+++		sch->stats.packets++;
+++		return 0;
+++	}
+++
+++	esfq_drop(sch);
+++	return NET_XMIT_CN;
+++}
+++
+++static int
+++esfq_requeue(struct sk_buff *skb, struct Qdisc* sch)
+++{
+++	struct esfq_sched_data *q = qdisc_priv(sch);
+++	unsigned hash = esfq_hash(q, skb);
+++	unsigned depth = q->depth;
+++	esfq_index x;
+++
+++	x = q->ht[hash];
+++	if (x == depth) {
+++		q->ht[hash] = x = q->dep[depth].next;
+++		q->hash[x] = hash;
+++	}
+++	sch->stats.backlog += skb->len;
+++	__skb_queue_head(&q->qs[x], skb);
+++	esfq_inc(q, x);
+++	if (q->qs[x].qlen == 1) {		/* The flow is new */
+++		if (q->tail == depth) {	/* It is the first flow */
+++			q->tail = x;
+++			q->next[x] = x;
+++			q->allot[x] = q->quantum;
+++		} else {
+++			q->next[x] = q->next[q->tail];
+++			q->next[q->tail] = x;
+++			q->tail = x;
+++		}
+++	}
+++	if (++sch->q.qlen < q->limit - 1) {
+++		return 0;
+++	}
+++
+++	sch->stats.drops++;
+++	esfq_drop(sch);
+++	return NET_XMIT_CN;
+++}
+++
+++
+++
+++
+++static struct sk_buff *
+++esfq_dequeue(struct Qdisc* sch)
+++{
+++	struct esfq_sched_data *q = qdisc_priv(sch);
+++	struct sk_buff *skb;
+++	unsigned depth = q->depth;
+++	esfq_index a, old_a;
+++
+++	/* No active slots */
+++	if (q->tail == depth)
+++		return NULL;
+++	
+++	a = old_a = q->next[q->tail];
+++	
+++	/* Grab packet */
+++	skb = __skb_dequeue(&q->qs[a]);
+++	esfq_dec(q, a);
+++	sch->q.qlen--;
+++	sch->stats.backlog -= skb->len;
+++	
+++	/* Is the slot empty? */
+++	if (q->qs[a].qlen == 0) {
+++		q->ht[q->hash[a]] = depth;
+++		a = q->next[a];
+++		if (a == old_a) {
+++			q->tail = depth;
+++			return skb;
+++		}
+++		q->next[q->tail] = a;
+++		q->allot[a] += q->quantum;
+++	} else if ((q->allot[a] -= skb->len) <= 0) {
+++		q->tail = a;
+++		a = q->next[a];
+++		q->allot[a] += q->quantum;
+++	}
+++	
+++	return skb;
+++}
+++
+++static void
+++esfq_reset(struct Qdisc* sch)
+++{
+++	struct sk_buff *skb;
+++
+++	while ((skb = esfq_dequeue(sch)) != NULL)
+++		kfree_skb(skb);
+++}
+++
+++static void esfq_perturbation(unsigned long arg)
+++{
+++	struct Qdisc *sch = (struct Qdisc*)arg;
+++	struct esfq_sched_data *q = qdisc_priv(sch);
+++
+++	q->perturbation = net_random()&0x1F;
+++
+++	if (q->perturb_period) {
+++		q->perturb_timer.expires = jiffies + q->perturb_period;
+++		add_timer(&q->perturb_timer);
+++	}
+++}
+++
+++static int esfq_change(struct Qdisc *sch, struct rtattr *opt)
+++{
+++	struct esfq_sched_data *q = qdisc_priv(sch);
+++	struct tc_esfq_qopt *ctl = RTA_DATA(opt);
+++	int old_perturb = q->perturb_period;
+++	
+++	if (opt->rta_len < RTA_LENGTH(sizeof(*ctl)))
+++		return -EINVAL;
+++	
+++	sch_tree_lock(sch);
+++	q->quantum = ctl->quantum ? : psched_mtu(sch->dev);
+++	q->perturb_period = ctl->perturb_period*HZ;
+++//	q->hash_divisor = ctl->divisor;
+++//	q->tail = q->limit = q->depth = ctl->flows;
+++	
+++	if (ctl->limit)
+++		q->limit = min_t(u32, ctl->limit, q->depth);
+++	
+++	if (ctl->hash_kind) {
+++		q->hash_kind = ctl->hash_kind;
+++		if (q->hash_kind != TCA_SFQ_HASH_CLASSIC)
+++			q->perturb_period = 0;
+++	}
+++	
+++	// is sch_tree_lock enough to do this ?
+++	while (sch->q.qlen >= q->limit-1)
+++		esfq_drop(sch);
+++	
+++	if (old_perturb)
+++		del_timer(&q->perturb_timer);
+++	if (q->perturb_period) {
+++		q->perturb_timer.expires = jiffies + q->perturb_period;
+++		add_timer(&q->perturb_timer);
+++	} else {
+++		q->perturbation = 0;
+++	}
+++	sch_tree_unlock(sch);
+++	return 0;
+++}
+++
+++static int esfq_init(struct Qdisc *sch, struct rtattr *opt)
+++{
+++	struct esfq_sched_data *q = qdisc_priv(sch);
+++	struct tc_esfq_qopt *ctl;
+++	esfq_index p = ~0U/2;
+++	int i;
+++	
+++	if (opt && opt->rta_len < RTA_LENGTH(sizeof(*ctl)))
+++		return -EINVAL;
+++
+++	init_timer(&q->perturb_timer);
+++	q->perturb_timer.data = (unsigned long)sch;
+++	q->perturb_timer.function = esfq_perturbation;
+++	q->perturbation = 0;
+++	q->hash_kind = TCA_SFQ_HASH_CLASSIC;
+++	q->max_depth = 0;
+++	q->dyn_min = ~0U; /* maximum value for this type */
+++	q->dyn_max = 0;  /* dyn_min/dyn_max will be set properly upon first packet */
+++	if (opt == NULL) {
+++		q->quantum = psched_mtu(sch->dev);
+++		q->perturb_period = 0;
+++		q->hash_divisor = 1024;
+++		q->tail = q->limit = q->depth = 128;
+++		
+++	} else {
+++		ctl = RTA_DATA(opt);
+++		q->quantum = ctl->quantum ? : psched_mtu(sch->dev);
+++		q->perturb_period = ctl->perturb_period*HZ;
+++		q->hash_divisor = ctl->divisor ? : 1024;
+++		q->tail = q->limit = q->depth = ctl->flows ? : 128;
+++		
+++		if ( q->depth > p - 1 )
+++			return -EINVAL;
+++		
+++		if (ctl->limit)
+++			q->limit = min_t(u32, ctl->limit, q->depth);
+++		
+++		if (ctl->hash_kind) {
+++			q->hash_kind = ctl->hash_kind;
+++		}
+++		
+++		if (q->perturb_period) {
+++			q->perturb_timer.expires = jiffies + q->perturb_period;
+++			add_timer(&q->perturb_timer);
+++		}
+++	}
+++	
+++	q->ht = kmalloc(q->hash_divisor*sizeof(esfq_index), GFP_KERNEL);
+++	if (!q->ht)
+++		goto err_case;
+++		
+++	q->dep = kmalloc((1+q->depth*2)*sizeof(struct esfq_head), GFP_KERNEL);
+++	if (!q->dep)
+++		goto err_case;
+++	q->next = kmalloc(q->depth*sizeof(esfq_index), GFP_KERNEL);
+++	if (!q->next)
+++		goto err_case;
+++	
+++	q->allot = kmalloc(q->depth*sizeof(short), GFP_KERNEL);
+++	if (!q->allot)
+++		goto err_case;
+++	q->hash = kmalloc(q->depth*sizeof(unsigned short), GFP_KERNEL);
+++	if (!q->hash)
+++		goto err_case;
+++	q->qs = kmalloc(q->depth*sizeof(struct sk_buff_head), GFP_KERNEL);
+++	if (!q->qs)
+++		goto err_case;
+++	
+++	for (i=0; i< q->hash_divisor; i++)
+++		q->ht[i] = q->depth;
+++	for (i=0; i<q->depth; i++) {
+++		skb_queue_head_init(&q->qs[i]);
+++		q->dep[i+q->depth].next = i+q->depth;
+++		q->dep[i+q->depth].prev = i+q->depth;
+++	}
+++	
+++	for (i=0; i<q->depth; i++)
+++		esfq_link(q, i);
+++	return 0;
+++err_case:
+++	del_timer(&q->perturb_timer);
+++	if (q->ht)
+++		kfree(q->ht);
+++	if (q->dep)
+++		kfree(q->dep);
+++	if (q->next)
+++		kfree(q->next);
+++	if (q->allot)
+++		kfree(q->allot);
+++	if (q->hash)
+++		kfree(q->hash);
+++	if (q->qs)
+++		kfree(q->qs);
+++	return -ENOBUFS;
+++}
+++
+++static void esfq_destroy(struct Qdisc *sch)
+++{
+++	struct esfq_sched_data *q = qdisc_priv(sch);
+++	del_timer(&q->perturb_timer);
+++	if(q->ht)
+++		kfree(q->ht);
+++	if(q->dep)
+++		kfree(q->dep);
+++	if(q->next)
+++		kfree(q->next);
+++	if(q->allot)
+++		kfree(q->allot);
+++	if(q->hash)
+++		kfree(q->hash);
+++	if(q->qs)
+++		kfree(q->qs);
+++}
+++
+++static int esfq_dump(struct Qdisc *sch, struct sk_buff *skb)
+++{
+++	struct esfq_sched_data *q = qdisc_priv(sch);
+++	unsigned char	 *b = skb->tail;
+++	struct tc_esfq_qopt opt;
+++
+++	opt.quantum = q->quantum;
+++	opt.perturb_period = q->perturb_period/HZ;
+++
+++	opt.limit = q->limit;
+++	opt.divisor = q->hash_divisor;
+++	opt.flows = q->depth;
+++	opt.hash_kind = q->hash_kind;
+++
+++	RTA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt);
+++
+++	return skb->len;
+++
+++rtattr_failure:
+++	skb_trim(skb, b - skb->data);
+++	return -1;
+++}
+++
+++static struct Qdisc_ops esfq_qdisc_ops =
+++{
+++	.next		=	NULL,
+++	.cl_ops		=	NULL,
+++	.id		=	"esfq",
+++	.priv_size	=	sizeof(struct esfq_sched_data),
+++	.enqueue	=	esfq_enqueue,
+++	.dequeue	=	esfq_dequeue,
+++	.requeue	=	esfq_requeue,
+++	.drop		=	esfq_drop,
+++	.init		=	esfq_init,
+++	.reset		=	esfq_reset,
+++	.destroy	=	esfq_destroy,
+++	.change		=	NULL, /* esfq_change - needs more work */
+++	.dump		=	esfq_dump,
+++};
+++
+++static int __init esfq_module_init(void)
+++{
+++	return register_qdisc(&esfq_qdisc_ops);
+++}
+++static void __exit esfq_module_exit(void) 
+++{
+++	unregister_qdisc(&esfq_qdisc_ops);
+++}
+++module_init(esfq_module_init)
+++module_exit(esfq_module_exit)
+++MODULE_LICENSE("GPL");