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	 6ab3d5624e
			
		
	
	
		6ab3d5624e
		
	
	
	
	
		
			
			Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
		
			
				
	
	
		
			112 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			112 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * net/sched/sch_fifo.c	The simplest FIFO queue.
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|  *
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|  *		This program is free software; you can redistribute it and/or
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|  *		modify it under the terms of the GNU General Public License
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|  *		as published by the Free Software Foundation; either version
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|  *		2 of the License, or (at your option) any later version.
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|  *
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|  * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
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|  */
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| 
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| #include <linux/module.h>
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| #include <linux/types.h>
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| #include <linux/kernel.h>
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| #include <linux/errno.h>
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| #include <linux/netdevice.h>
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| #include <linux/skbuff.h>
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| #include <net/pkt_sched.h>
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| 
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| /* 1 band FIFO pseudo-"scheduler" */
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| 
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| struct fifo_sched_data
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| {
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| 	u32 limit;
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| };
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| 
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| static int bfifo_enqueue(struct sk_buff *skb, struct Qdisc* sch)
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| {
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| 	struct fifo_sched_data *q = qdisc_priv(sch);
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| 
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| 	if (likely(sch->qstats.backlog + skb->len <= q->limit))
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| 		return qdisc_enqueue_tail(skb, sch);
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| 
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| 	return qdisc_reshape_fail(skb, sch);
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| }
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| 
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| static int pfifo_enqueue(struct sk_buff *skb, struct Qdisc* sch)
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| {
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| 	struct fifo_sched_data *q = qdisc_priv(sch);
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| 
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| 	if (likely(skb_queue_len(&sch->q) < q->limit))
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| 		return qdisc_enqueue_tail(skb, sch);
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| 
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| 	return qdisc_reshape_fail(skb, sch);
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| }
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| 
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| static int fifo_init(struct Qdisc *sch, struct rtattr *opt)
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| {
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| 	struct fifo_sched_data *q = qdisc_priv(sch);
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| 
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| 	if (opt == NULL) {
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| 		u32 limit = sch->dev->tx_queue_len ? : 1;
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| 
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| 		if (sch->ops == &bfifo_qdisc_ops)
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| 			limit *= sch->dev->mtu;
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| 
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| 		q->limit = limit;
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| 	} else {
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| 		struct tc_fifo_qopt *ctl = RTA_DATA(opt);
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| 
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| 		if (RTA_PAYLOAD(opt) < sizeof(*ctl))
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| 			return -EINVAL;
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| 
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| 		q->limit = ctl->limit;
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| 	}
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| 
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| 	return 0;
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| }
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| 
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| static int fifo_dump(struct Qdisc *sch, struct sk_buff *skb)
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| {
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| 	struct fifo_sched_data *q = qdisc_priv(sch);
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| 	struct tc_fifo_qopt opt = { .limit = q->limit };
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| 
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| 	RTA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt);
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| 	return skb->len;
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| 
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| rtattr_failure:
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| 	return -1;
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| }
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| 
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| struct Qdisc_ops pfifo_qdisc_ops = {
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| 	.id		=	"pfifo",
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| 	.priv_size	=	sizeof(struct fifo_sched_data),
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| 	.enqueue	=	pfifo_enqueue,
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| 	.dequeue	=	qdisc_dequeue_head,
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| 	.requeue	=	qdisc_requeue,
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| 	.drop		=	qdisc_queue_drop,
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| 	.init		=	fifo_init,
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| 	.reset		=	qdisc_reset_queue,
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| 	.change		=	fifo_init,
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| 	.dump		=	fifo_dump,
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| 	.owner		=	THIS_MODULE,
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| };
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| 
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| struct Qdisc_ops bfifo_qdisc_ops = {
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| 	.id		=	"bfifo",
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| 	.priv_size	=	sizeof(struct fifo_sched_data),
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| 	.enqueue	=	bfifo_enqueue,
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| 	.dequeue	=	qdisc_dequeue_head,
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| 	.requeue	=	qdisc_requeue,
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| 	.drop		=	qdisc_queue_drop,
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| 	.init		=	fifo_init,
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| 	.reset		=	qdisc_reset_queue,
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| 	.change		=	fifo_init,
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| 	.dump		=	fifo_dump,
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| 	.owner		=	THIS_MODULE,
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| };
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| 
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| EXPORT_SYMBOL(bfifo_qdisc_ops);
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| EXPORT_SYMBOL(pfifo_qdisc_ops);
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