blob: 132a5bc94294d206dd745ee1fd6bfe45cf2020a9 [file] [log] [blame]
/*
* net/sched/sch_fifo.c The simplest FIFO queue.
*
* 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 <linux/config.h>
#include <linux/module.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/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 <net/ip.h>
#include <net/route.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <net/pkt_sched.h>
/* 1 band FIFO pseudo-"scheduler" */
struct fifo_sched_data
{
unsigned limit;
};
static int
bfifo_enqueue(struct sk_buff *skb, struct Qdisc* sch)
{
struct fifo_sched_data *q = (struct fifo_sched_data *)sch->data;
if (sch->stats.backlog + skb->len <= q->limit) {
__skb_queue_tail(&sch->q, skb);
sch->stats.backlog += skb->len;
sch->stats.bytes += skb->len;
sch->stats.packets++;
return 0;
}
sch->stats.drops++;
#ifdef CONFIG_NET_CLS_POLICE
if (sch->reshape_fail==NULL || sch->reshape_fail(skb, sch))
#endif
kfree_skb(skb);
return NET_XMIT_DROP;
}
static int
bfifo_requeue(struct sk_buff *skb, struct Qdisc* sch)
{
__skb_queue_head(&sch->q, skb);
sch->stats.backlog += skb->len;
return 0;
}
static struct sk_buff *
bfifo_dequeue(struct Qdisc* sch)
{
struct sk_buff *skb;
skb = __skb_dequeue(&sch->q);
if (skb)
sch->stats.backlog -= skb->len;
return skb;
}
static unsigned int
fifo_drop(struct Qdisc* sch)
{
struct sk_buff *skb;
skb = __skb_dequeue_tail(&sch->q);
if (skb) {
unsigned int len = skb->len;
sch->stats.backlog -= len;
kfree_skb(skb);
return len;
}
return 0;
}
static void
fifo_reset(struct Qdisc* sch)
{
skb_queue_purge(&sch->q);
sch->stats.backlog = 0;
}
static int
pfifo_enqueue(struct sk_buff *skb, struct Qdisc* sch)
{
struct fifo_sched_data *q = (struct fifo_sched_data *)sch->data;
if (sch->q.qlen < q->limit) {
__skb_queue_tail(&sch->q, skb);
sch->stats.bytes += skb->len;
sch->stats.packets++;
return 0;
}
sch->stats.drops++;
#ifdef CONFIG_NET_CLS_POLICE
if (sch->reshape_fail==NULL || sch->reshape_fail(skb, sch))
#endif
kfree_skb(skb);
return NET_XMIT_DROP;
}
static int
pfifo_requeue(struct sk_buff *skb, struct Qdisc* sch)
{
__skb_queue_head(&sch->q, skb);
return 0;
}
static struct sk_buff *
pfifo_dequeue(struct Qdisc* sch)
{
return __skb_dequeue(&sch->q);
}
static int fifo_init(struct Qdisc *sch, struct rtattr *opt)
{
struct fifo_sched_data *q = (void*)sch->data;
if (opt == NULL) {
unsigned int limit = sch->dev->tx_queue_len ? : 1;
if (sch->ops == &bfifo_qdisc_ops)
q->limit = limit*sch->dev->mtu;
else
q->limit = limit;
} else {
struct tc_fifo_qopt *ctl = RTA_DATA(opt);
if (opt->rta_len < RTA_LENGTH(sizeof(*ctl)))
return -EINVAL;
q->limit = ctl->limit;
}
return 0;
}
static int fifo_dump(struct Qdisc *sch, struct sk_buff *skb)
{
struct fifo_sched_data *q = (void*)sch->data;
unsigned char *b = skb->tail;
struct tc_fifo_qopt opt;
opt.limit = q->limit;
RTA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt);
return skb->len;
rtattr_failure:
skb_trim(skb, b - skb->data);
return -1;
}
struct Qdisc_ops pfifo_qdisc_ops = {
.next = NULL,
.cl_ops = NULL,
.id = "pfifo",
.priv_size = sizeof(struct fifo_sched_data),
.enqueue = pfifo_enqueue,
.dequeue = pfifo_dequeue,
.requeue = pfifo_requeue,
.drop = fifo_drop,
.init = fifo_init,
.reset = fifo_reset,
.destroy = NULL,
.change = fifo_init,
.dump = fifo_dump,
.owner = THIS_MODULE,
};
struct Qdisc_ops bfifo_qdisc_ops = {
.next = NULL,
.cl_ops = NULL,
.id = "bfifo",
.priv_size = sizeof(struct fifo_sched_data),
.enqueue = bfifo_enqueue,
.dequeue = bfifo_dequeue,
.requeue = bfifo_requeue,
.drop = fifo_drop,
.init = fifo_init,
.reset = fifo_reset,
.destroy = NULL,
.change = fifo_init,
.dump = fifo_dump,
.owner = THIS_MODULE,
};
EXPORT_SYMBOL(bfifo_qdisc_ops);
EXPORT_SYMBOL(pfifo_qdisc_ops);