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-rw-r--r--net/sched/sch_fifo.c212
1 files changed, 212 insertions, 0 deletions
diff --git a/net/sched/sch_fifo.c b/net/sched/sch_fifo.c
new file mode 100644
index 00000000000..4888305c96d
--- /dev/null
+++ b/net/sched/sch_fifo.c
@@ -0,0 +1,212 @@
+/*
+ * 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 <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 <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 = qdisc_priv(sch);
+
+ if (sch->qstats.backlog + skb->len <= q->limit) {
+ __skb_queue_tail(&sch->q, skb);
+ sch->qstats.backlog += skb->len;
+ sch->bstats.bytes += skb->len;
+ sch->bstats.packets++;
+ return 0;
+ }
+ sch->qstats.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->qstats.backlog += skb->len;
+ sch->qstats.requeues++;
+ return 0;
+}
+
+static struct sk_buff *
+bfifo_dequeue(struct Qdisc* sch)
+{
+ struct sk_buff *skb;
+
+ skb = __skb_dequeue(&sch->q);
+ if (skb)
+ sch->qstats.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->qstats.backlog -= len;
+ kfree_skb(skb);
+ return len;
+ }
+ return 0;
+}
+
+static void
+fifo_reset(struct Qdisc* sch)
+{
+ skb_queue_purge(&sch->q);
+ sch->qstats.backlog = 0;
+}
+
+static int
+pfifo_enqueue(struct sk_buff *skb, struct Qdisc* sch)
+{
+ struct fifo_sched_data *q = qdisc_priv(sch);
+
+ if (sch->q.qlen < q->limit) {
+ __skb_queue_tail(&sch->q, skb);
+ sch->bstats.bytes += skb->len;
+ sch->bstats.packets++;
+ return 0;
+ }
+ sch->qstats.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);
+ sch->qstats.requeues++;
+ 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 = qdisc_priv(sch);
+
+ 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 = qdisc_priv(sch);
+ 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);