111 lines
2.5 KiB
C
111 lines
2.5 KiB
C
/*
|
|
* 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/module.h>
|
|
#include <linux/types.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/skbuff.h>
|
|
#include <net/pkt_sched.h>
|
|
|
|
/* 1 band FIFO pseudo-"scheduler" */
|
|
|
|
struct fifo_sched_data
|
|
{
|
|
u32 limit;
|
|
};
|
|
|
|
static int bfifo_enqueue(struct sk_buff *skb, struct Qdisc* sch)
|
|
{
|
|
struct fifo_sched_data *q = qdisc_priv(sch);
|
|
|
|
if (likely(sch->qstats.backlog + skb->len <= q->limit))
|
|
return qdisc_enqueue_tail(skb, sch);
|
|
|
|
return qdisc_reshape_fail(skb, sch);
|
|
}
|
|
|
|
static int pfifo_enqueue(struct sk_buff *skb, struct Qdisc* sch)
|
|
{
|
|
struct fifo_sched_data *q = qdisc_priv(sch);
|
|
|
|
if (likely(skb_queue_len(&sch->q) < q->limit))
|
|
return qdisc_enqueue_tail(skb, sch);
|
|
|
|
return qdisc_reshape_fail(skb, sch);
|
|
}
|
|
|
|
static int fifo_init(struct Qdisc *sch, struct rtattr *opt)
|
|
{
|
|
struct fifo_sched_data *q = qdisc_priv(sch);
|
|
|
|
if (opt == NULL) {
|
|
u32 limit = sch->dev->tx_queue_len ? : 1;
|
|
|
|
if (sch->ops == &bfifo_qdisc_ops)
|
|
limit *= sch->dev->mtu;
|
|
|
|
q->limit = limit;
|
|
} else {
|
|
struct tc_fifo_qopt *ctl = RTA_DATA(opt);
|
|
|
|
if (RTA_PAYLOAD(opt) < 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 = qdisc_priv(sch);
|
|
struct tc_fifo_qopt opt = { .limit = q->limit };
|
|
|
|
RTA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt);
|
|
return skb->len;
|
|
|
|
rtattr_failure:
|
|
return -1;
|
|
}
|
|
|
|
struct Qdisc_ops pfifo_qdisc_ops = {
|
|
.id = "pfifo",
|
|
.priv_size = sizeof(struct fifo_sched_data),
|
|
.enqueue = pfifo_enqueue,
|
|
.dequeue = qdisc_dequeue_head,
|
|
.requeue = qdisc_requeue,
|
|
.drop = qdisc_queue_drop,
|
|
.init = fifo_init,
|
|
.reset = qdisc_reset_queue,
|
|
.change = fifo_init,
|
|
.dump = fifo_dump,
|
|
.owner = THIS_MODULE,
|
|
};
|
|
|
|
struct Qdisc_ops bfifo_qdisc_ops = {
|
|
.id = "bfifo",
|
|
.priv_size = sizeof(struct fifo_sched_data),
|
|
.enqueue = bfifo_enqueue,
|
|
.dequeue = qdisc_dequeue_head,
|
|
.requeue = qdisc_requeue,
|
|
.drop = qdisc_queue_drop,
|
|
.init = fifo_init,
|
|
.reset = qdisc_reset_queue,
|
|
.change = fifo_init,
|
|
.dump = fifo_dump,
|
|
.owner = THIS_MODULE,
|
|
};
|
|
|
|
EXPORT_SYMBOL(bfifo_qdisc_ops);
|
|
EXPORT_SYMBOL(pfifo_qdisc_ops);
|