2 * net/sched/sch_fifo.c The simplest FIFO queue.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
9 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
12 #include <linux/config.h>
13 #include <asm/uaccess.h>
14 #include <asm/system.h>
15 #include <asm/bitops.h>
16 #include <linux/types.h>
17 #include <linux/kernel.h>
18 #include <linux/sched.h>
19 #include <linux/string.h>
21 #include <linux/socket.h>
22 #include <linux/sockios.h>
24 #include <linux/errno.h>
25 #include <linux/interrupt.h>
26 #include <linux/if_ether.h>
27 #include <linux/inet.h>
28 #include <linux/netdevice.h>
29 #include <linux/etherdevice.h>
30 #include <linux/notifier.h>
32 #include <net/route.h>
33 #include <linux/skbuff.h>
35 #include <net/pkt_sched.h>
37 /* 1 band FIFO pseudo-"scheduler" */
39 struct fifo_sched_data
45 bfifo_enqueue(struct sk_buff *skb, struct Qdisc* sch)
47 struct fifo_sched_data *q = (struct fifo_sched_data *)sch->data;
49 if (sch->stats.backlog <= q->limit) {
50 __skb_queue_tail(&sch->q, skb);
51 sch->stats.backlog += skb->len;
52 sch->stats.bytes += skb->len;
57 #ifdef CONFIG_NET_CLS_POLICE
58 if (sch->reshape_fail==NULL || sch->reshape_fail(skb, sch))
65 bfifo_requeue(struct sk_buff *skb, struct Qdisc* sch)
67 __skb_queue_head(&sch->q, skb);
68 sch->stats.backlog += skb->len;
72 static struct sk_buff *
73 bfifo_dequeue(struct Qdisc* sch)
77 skb = __skb_dequeue(&sch->q);
79 sch->stats.backlog -= skb->len;
84 fifo_drop(struct Qdisc* sch)
88 skb = __skb_dequeue_tail(&sch->q);
90 sch->stats.backlog -= skb->len;
98 fifo_reset(struct Qdisc* sch)
100 skb_queue_purge(&sch->q);
101 sch->stats.backlog = 0;
105 pfifo_enqueue(struct sk_buff *skb, struct Qdisc* sch)
107 struct fifo_sched_data *q = (struct fifo_sched_data *)sch->data;
109 if (sch->q.qlen <= q->limit) {
110 __skb_queue_tail(&sch->q, skb);
111 sch->stats.bytes += skb->len;
112 sch->stats.packets++;
116 #ifdef CONFIG_NET_CLS_POLICE
117 if (sch->reshape_fail==NULL || sch->reshape_fail(skb, sch))
120 return NET_XMIT_DROP;
124 pfifo_requeue(struct sk_buff *skb, struct Qdisc* sch)
126 __skb_queue_head(&sch->q, skb);
131 static struct sk_buff *
132 pfifo_dequeue(struct Qdisc* sch)
134 return __skb_dequeue(&sch->q);
137 static int fifo_init(struct Qdisc *sch, struct rtattr *opt)
139 struct fifo_sched_data *q = (void*)sch->data;
142 if (sch->ops == &bfifo_qdisc_ops)
143 q->limit = sch->dev->tx_queue_len*sch->dev->mtu;
145 q->limit = sch->dev->tx_queue_len;
147 struct tc_fifo_qopt *ctl = RTA_DATA(opt);
148 if (opt->rta_len < RTA_LENGTH(sizeof(*ctl)))
150 q->limit = ctl->limit;
155 static int fifo_dump(struct Qdisc *sch, struct sk_buff *skb)
157 struct fifo_sched_data *q = (void*)sch->data;
158 unsigned char *b = skb->tail;
159 struct tc_fifo_qopt opt;
161 opt.limit = q->limit;
162 RTA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt);
167 skb_trim(skb, b - skb->data);
171 struct Qdisc_ops pfifo_qdisc_ops =
176 sizeof(struct fifo_sched_data),
191 struct Qdisc_ops bfifo_qdisc_ops =
196 sizeof(struct fifo_sched_data),