[linux-2.6-block.git] / net / sched / sch_prio.c

/*
 * net/sched/sch_prio.c	Simple 3-band priority "scheduler".
 *
 *		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>
 * Fixes:       19990609: J Hadi Salim <hadi@nortelnetworks.com>:
 *              Init --  EINVAL when opt undefined
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/skbuff.h>
#include <net/netlink.h>
#include <net/pkt_sched.h>


struct prio_sched_data
{
	int bands;
	struct tcf_proto *filter_list;
	u8  prio2band[TC_PRIO_MAX+1];
	struct Qdisc *queues[TCQ_PRIO_BANDS];
};


static struct Qdisc *
prio_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
{
	struct prio_sched_data *q = qdisc_priv(sch);
	u32 band = skb->priority;
	struct tcf_result res;
	int err;

	*qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
	if (TC_H_MAJ(skb->priority) != sch->handle) {
		err = tc_classify(skb, q->filter_list, &res);
#ifdef CONFIG_NET_CLS_ACT
		switch (err) {
		case TC_ACT_STOLEN:
		case TC_ACT_QUEUED:
			*qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
		case TC_ACT_SHOT:
			return NULL;
		}
#endif
		if (!q->filter_list || err < 0) {
			if (TC_H_MAJ(band))
				band = 0;
			return q->queues[q->prio2band[band&TC_PRIO_MAX]];
		}
		band = res.classid;
	}
	band = TC_H_MIN(band) - 1;
	if (band >= q->bands)
		return q->queues[q->prio2band[0]];

	return q->queues[band];
}

static int
prio_enqueue(struct sk_buff *skb, struct Qdisc *sch)
{
	struct Qdisc *qdisc;
	int ret;

	qdisc = prio_classify(skb, sch, &ret);
#ifdef CONFIG_NET_CLS_ACT
	if (qdisc == NULL) {

		if (ret & __NET_XMIT_BYPASS)
			sch->qstats.drops++;
		kfree_skb(skb);
		return ret;
	}
#endif

	ret = qdisc_enqueue(skb, qdisc);
	if (ret == NET_XMIT_SUCCESS) {
		sch->bstats.bytes += qdisc_pkt_len(skb);
		sch->bstats.packets++;
		sch->q.qlen++;
		return NET_XMIT_SUCCESS;
	}
	if (net_xmit_drop_count(ret))
		sch->qstats.drops++;
	return ret;
}


static int
prio_requeue(struct sk_buff *skb, struct Qdisc* sch)
{
	struct Qdisc *qdisc;
	int ret;

	qdisc = prio_classify(skb, sch, &ret);
#ifdef CONFIG_NET_CLS_ACT
	if (qdisc == NULL) {
		if (ret & __NET_XMIT_BYPASS)
			sch->qstats.drops++;
		kfree_skb(skb);
		return ret;
	}
#endif

	if ((ret = qdisc->ops->requeue(skb, qdisc)) == NET_XMIT_SUCCESS) {
		sch->q.qlen++;
		sch->qstats.requeues++;
		return NET_XMIT_SUCCESS;
	}
	if (net_xmit_drop_count(ret))
		sch->qstats.drops++;
	return ret;
}


static struct sk_buff *prio_dequeue(struct Qdisc* sch)
{
	struct prio_sched_data *q = qdisc_priv(sch);
	int prio;

	for (prio = 0; prio < q->bands; prio++) {
		struct Qdisc *qdisc = q->queues[prio];
		struct sk_buff *skb = qdisc->dequeue(qdisc);
		if (skb) {
			sch->q.qlen--;
			return skb;
		}
	}
	return NULL;

}

static unsigned int prio_drop(struct Qdisc* sch)
{
	struct prio_sched_data *q = qdisc_priv(sch);
	int prio;
	unsigned int len;
	struct Qdisc *qdisc;

	for (prio = q->bands-1; prio >= 0; prio--) {
		qdisc = q->queues[prio];
		if (qdisc->ops->drop && (len = qdisc->ops->drop(qdisc)) != 0) {
			sch->q.qlen--;
			return len;
		}
	}
	return 0;
}


static void
prio_reset(struct Qdisc* sch)
{
	int prio;
	struct prio_sched_data *q = qdisc_priv(sch);

	for (prio=0; prio<q->bands; prio++)
		qdisc_reset(q->queues[prio]);
	sch->q.qlen = 0;
}

static void
prio_destroy(struct Qdisc* sch)
{
	int prio;
	struct prio_sched_data *q = qdisc_priv(sch);

	tcf_destroy_chain(&q->filter_list);
	for (prio=0; prio<q->bands; prio++)
		qdisc_destroy(q->queues[prio]);
}

static int prio_tune(struct Qdisc *sch, struct nlattr *opt)
{
	struct prio_sched_data *q = qdisc_priv(sch);
	struct tc_prio_qopt *qopt;
	int i;

	if (nla_len(opt) < sizeof(*qopt))
		return -EINVAL;
	qopt = nla_data(opt);

	if (qopt->bands > TCQ_PRIO_BANDS || qopt->bands < 2)
		return -EINVAL;

	for (i=0; i<=TC_PRIO_MAX; i++) {
		if (qopt->priomap[i] >= qopt->bands)
			return -EINVAL;
	}

	sch_tree_lock(sch);
	q->bands = qopt->bands;
	memcpy(q->prio2band, qopt->priomap, TC_PRIO_MAX+1);

	for (i=q->bands; i<TCQ_PRIO_BANDS; i++) {
		struct Qdisc *child = xchg(&q->queues[i], &noop_qdisc);
		if (child != &noop_qdisc) {
			qdisc_tree_decrease_qlen(child, child->q.qlen);
			qdisc_destroy(child);
		}
	}
	sch_tree_unlock(sch);

	for (i=0; i<q->bands; i++) {
		if (q->queues[i] == &noop_qdisc) {
			struct Qdisc *child;
			child = qdisc_create_dflt(qdisc_dev(sch), sch->dev_queue,
						  &pfifo_qdisc_ops,
						  TC_H_MAKE(sch->handle, i + 1));
			if (child) {
				sch_tree_lock(sch);
				child = xchg(&q->queues[i], child);

				if (child != &noop_qdisc) {
					qdisc_tree_decrease_qlen(child,
								 child->q.qlen);
					qdisc_destroy(child);
				}
				sch_tree_unlock(sch);
			}
		}
	}
	return 0;
}

static int prio_init(struct Qdisc *sch, struct nlattr *opt)
{
	struct prio_sched_data *q = qdisc_priv(sch);
	int i;

	for (i=0; i<TCQ_PRIO_BANDS; i++)
		q->queues[i] = &noop_qdisc;

	if (opt == NULL) {
		return -EINVAL;
	} else {
		int err;

		if ((err= prio_tune(sch, opt)) != 0)
			return err;
	}
	return 0;
}

static int prio_dump(struct Qdisc *sch, struct sk_buff *skb)
{
	struct prio_sched_data *q = qdisc_priv(sch);
	unsigned char *b = skb_tail_pointer(skb);
	struct nlattr *nest;
	struct tc_prio_qopt opt;

	opt.bands = q->bands;
	memcpy(&opt.priomap, q->prio2band, TC_PRIO_MAX+1);

	nest = nla_nest_compat_start(skb, TCA_OPTIONS, sizeof(opt), &opt);
	if (nest == NULL)
		goto nla_put_failure;
	nla_nest_compat_end(skb, nest);

	return skb->len;

nla_put_failure:
	nlmsg_trim(skb, b);
	return -1;
}

static int prio_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
		      struct Qdisc **old)
{
	struct prio_sched_data *q = qdisc_priv(sch);
	unsigned long band = arg - 1;

	if (band >= q->bands)
		return -EINVAL;

	if (new == NULL)
		new = &noop_qdisc;

	sch_tree_lock(sch);
	*old = q->queues[band];
	q->queues[band] = new;
	qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
	qdisc_reset(*old);
	sch_tree_unlock(sch);

	return 0;
}

static struct Qdisc *
prio_leaf(struct Qdisc *sch, unsigned long arg)
{
	struct prio_sched_data *q = qdisc_priv(sch);
	unsigned long band = arg - 1;

	if (band >= q->bands)
		return NULL;

	return q->queues[band];
}

static unsigned long prio_get(struct Qdisc *sch, u32 classid)
{
	struct prio_sched_data *q = qdisc_priv(sch);
	unsigned long band = TC_H_MIN(classid);

	if (band - 1 >= q->bands)
		return 0;
	return band;
}

static unsigned long prio_bind(struct Qdisc *sch, unsigned long parent, u32 classid)
{
	return prio_get(sch, classid);
}


static void prio_put(struct Qdisc *q, unsigned long cl)
{
	return;
}

static int prio_change(struct Qdisc *sch, u32 handle, u32 parent, struct nlattr **tca, unsigned long *arg)
{
	unsigned long cl = *arg;
	struct prio_sched_data *q = qdisc_priv(sch);

	if (cl - 1 > q->bands)
		return -ENOENT;
	return 0;
}

static int prio_delete(struct Qdisc *sch, unsigned long cl)
{
	struct prio_sched_data *q = qdisc_priv(sch);
	if (cl - 1 > q->bands)
		return -ENOENT;
	return 0;
}


static int prio_dump_class(struct Qdisc *sch, unsigned long cl, struct sk_buff *skb,
			   struct tcmsg *tcm)
{
	struct prio_sched_data *q = qdisc_priv(sch);

	if (cl - 1 > q->bands)
		return -ENOENT;
	tcm->tcm_handle |= TC_H_MIN(cl);
	if (q->queues[cl-1])
		tcm->tcm_info = q->queues[cl-1]->handle;
	return 0;
}

static int prio_dump_class_stats(struct Qdisc *sch, unsigned long cl,
				 struct gnet_dump *d)
{
	struct prio_sched_data *q = qdisc_priv(sch);
	struct Qdisc *cl_q;

	cl_q = q->queues[cl - 1];
	if (gnet_stats_copy_basic(d, &cl_q->bstats) < 0 ||
	    gnet_stats_copy_queue(d, &cl_q->qstats) < 0)
		return -1;

	return 0;
}

static void prio_walk(struct Qdisc *sch, struct qdisc_walker *arg)
{
	struct prio_sched_data *q = qdisc_priv(sch);
	int prio;

	if (arg->stop)
		return;

	for (prio = 0; prio < q->bands; prio++) {
		if (arg->count < arg->skip) {
			arg->count++;
			continue;
		}
		if (arg->fn(sch, prio+1, arg) < 0) {
			arg->stop = 1;
			break;
		}
		arg->count++;
	}
}

static struct tcf_proto ** prio_find_tcf(struct Qdisc *sch, unsigned long cl)
{
	struct prio_sched_data *q = qdisc_priv(sch);

	if (cl)
		return NULL;
	return &q->filter_list;
}

static const struct Qdisc_class_ops prio_class_ops = {
	.graft		=	prio_graft,
	.leaf		=	prio_leaf,
	.get		=	prio_get,
	.put		=	prio_put,
	.change		=	prio_change,
	.delete		=	prio_delete,
	.walk		=	prio_walk,
	.tcf_chain	=	prio_find_tcf,
	.bind_tcf	=	prio_bind,
	.unbind_tcf	=	prio_put,
	.dump		=	prio_dump_class,
	.dump_stats	=	prio_dump_class_stats,
};

static struct Qdisc_ops prio_qdisc_ops __read_mostly = {
	.next		=	NULL,
	.cl_ops		=	&prio_class_ops,
	.id		=	"prio",
	.priv_size	=	sizeof(struct prio_sched_data),
	.enqueue	=	prio_enqueue,
	.dequeue	=	prio_dequeue,
	.requeue	=	prio_requeue,
	.drop		=	prio_drop,
	.init		=	prio_init,
	.reset		=	prio_reset,
	.destroy	=	prio_destroy,
	.change		=	prio_tune,
	.dump		=	prio_dump,
	.owner		=	THIS_MODULE,
};

static int __init prio_module_init(void)
{
	return register_qdisc(&prio_qdisc_ops);
}

static void __exit prio_module_exit(void)
{
	unregister_qdisc(&prio_qdisc_ops);
}

module_init(prio_module_init)
module_exit(prio_module_exit)

MODULE_LICENSE("GPL");
Commit	Line	Data
1da177e4 LT	1	/*
	2	* net/sched/sch_prio.c Simple 3-band priority "scheduler".
	3	*
	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.
	8	*
	9	* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
10297b99	10	* Fixes: 19990609: J Hadi Salim <hadi@nortelnetworks.com>:
1da177e4 LT	11	* Init -- EINVAL when opt undefined
	12	*/
	13
1da177e4	14	#include <linux/module.h>
1da177e4 LT	15	#include <linux/types.h>
1da177e4 LT	16	#include <linux/kernel.h>
1da177e4	17	#include <linux/string.h>
1da177e4	18	#include <linux/errno.h>
1da177e4	19	#include <linux/skbuff.h>
dc5fc579	20	#include <net/netlink.h>
1da177e4 LT	21	#include <net/pkt_sched.h>
	22
	23
	24	struct prio_sched_data
	25	{
	26	int bands;
	27	struct tcf_proto *filter_list;
	28	u8 prio2band[TC_PRIO_MAX+1];
	29	struct Qdisc *queues[TCQ_PRIO_BANDS];
	30	};
	31
	32
	33	static struct Qdisc *
	34	prio_classify(struct sk_buff skb, struct Qdisc sch, int *qerr)
	35	{
	36	struct prio_sched_data *q = qdisc_priv(sch);
	37	u32 band = skb->priority;
	38	struct tcf_result res;
bdba91ec	39	int err;
1da177e4	40
c27f339a	41	*qerr = NET_XMIT_SUCCESS \| __NET_XMIT_BYPASS;
1da177e4	42	if (TC_H_MAJ(skb->priority) != sch->handle) {
bdba91ec	43	err = tc_classify(skb, q->filter_list, &res);
1da177e4	44	#ifdef CONFIG_NET_CLS_ACT
dbaaa07a	45	switch (err) {
1da177e4 LT	46	case TC_ACT_STOLEN:
1da177e4 LT	47	case TC_ACT_QUEUED:
378a2f09	48	*qerr = NET_XMIT_SUCCESS \| __NET_XMIT_STOLEN;
1da177e4 LT	49	case TC_ACT_SHOT:
1da177e4 LT	50	return NULL;
3ff50b79	51	}
1da177e4	52	#endif
bdba91ec	53	if (!q->filter_list \|\| err < 0) {
1da177e4 LT	54	if (TC_H_MAJ(band))
1da177e4 LT	55	band = 0;
1d8ae3fd	56	return q->queues[q->prio2band[band&TC_PRIO_MAX]];
1da177e4 LT	57	}
	58	band = res.classid;
	59	}
	60	band = TC_H_MIN(band) - 1;
3e5c2d3b	61	if (band >= q->bands)
1d8ae3fd DM	62	return q->queues[q->prio2band[0]];
1d8ae3fd DM	63
1da177e4 LT	64	return q->queues[band];
	65	}
	66
	67	static int
	68	prio_enqueue(struct sk_buff skb, struct Qdisc sch)
	69	{
	70	struct Qdisc *qdisc;
	71	int ret;
	72
	73	qdisc = prio_classify(skb, sch, &ret);
	74	#ifdef CONFIG_NET_CLS_ACT
	75	if (qdisc == NULL) {
29f1df6c	76
c27f339a	77	if (ret & __NET_XMIT_BYPASS)
1da177e4 LT	78	sch->qstats.drops++;
	79	kfree_skb(skb);
	80	return ret;
	81	}
	82	#endif
	83
5f86173b JK	84	ret = qdisc_enqueue(skb, qdisc);
5f86173b JK	85	if (ret == NET_XMIT_SUCCESS) {
0abf77e5	86	sch->bstats.bytes += qdisc_pkt_len(skb);
1da177e4 LT	87	sch->bstats.packets++;
	88	sch->q.qlen++;
	89	return NET_XMIT_SUCCESS;
	90	}
378a2f09 JP	91	if (net_xmit_drop_count(ret))
378a2f09 JP	92	sch->qstats.drops++;
10297b99	93	return ret;
1da177e4 LT	94	}
	95
	96
	97	static int
	98	prio_requeue(struct sk_buff skb, struct Qdisc sch)
	99	{
	100	struct Qdisc *qdisc;
	101	int ret;
	102
	103	qdisc = prio_classify(skb, sch, &ret);
	104	#ifdef CONFIG_NET_CLS_ACT
	105	if (qdisc == NULL) {
c27f339a	106	if (ret & __NET_XMIT_BYPASS)
1da177e4 LT	107	sch->qstats.drops++;
	108	kfree_skb(skb);
	109	return ret;
	110	}
	111	#endif
	112
	113	if ((ret = qdisc->ops->requeue(skb, qdisc)) == NET_XMIT_SUCCESS) {
	114	sch->q.qlen++;
	115	sch->qstats.requeues++;
4cf7cb28	116	return NET_XMIT_SUCCESS;
1da177e4	117	}
378a2f09 JP	118	if (net_xmit_drop_count(ret))
378a2f09 JP	119	sch->qstats.drops++;
0d40b6e5	120	return ret;
1da177e4 LT	121	}
	122
	123
1d8ae3fd	124	static struct sk_buff prio_dequeue(struct Qdisc sch)
1da177e4	125	{
1da177e4 LT	126	struct prio_sched_data *q = qdisc_priv(sch);
1da177e4 LT	127	int prio;
1da177e4 LT	128
1da177e4 LT	129	for (prio = 0; prio < q->bands; prio++) {
1d8ae3fd DM	130	struct Qdisc *qdisc = q->queues[prio];
	131	struct sk_buff *skb = qdisc->dequeue(qdisc);
	132	if (skb) {
	133	sch->q.qlen--;
	134	return skb;
1da177e4 LT	135	}
	136	}
	137	return NULL;
	138
	139	}
	140
	141	static unsigned int prio_drop(struct Qdisc* sch)
	142	{
	143	struct prio_sched_data *q = qdisc_priv(sch);
	144	int prio;
	145	unsigned int len;
	146	struct Qdisc *qdisc;
	147
	148	for (prio = q->bands-1; prio >= 0; prio--) {
	149	qdisc = q->queues[prio];
6d037a26	150	if (qdisc->ops->drop && (len = qdisc->ops->drop(qdisc)) != 0) {
1da177e4 LT	151	sch->q.qlen--;
	152	return len;
	153	}
	154	}
	155	return 0;
	156	}
	157
	158
	159	static void
	160	prio_reset(struct Qdisc* sch)
	161	{
	162	int prio;
	163	struct prio_sched_data *q = qdisc_priv(sch);
	164
	165	for (prio=0; prio<q->bands; prio++)
	166	qdisc_reset(q->queues[prio]);
	167	sch->q.qlen = 0;
	168	}
	169
	170	static void
	171	prio_destroy(struct Qdisc* sch)
	172	{
	173	int prio;
	174	struct prio_sched_data *q = qdisc_priv(sch);
1da177e4	175
ff31ab56	176	tcf_destroy_chain(&q->filter_list);
1da177e4 LT	177	for (prio=0; prio<q->bands; prio++)
	178	qdisc_destroy(q->queues[prio]);
	179	}
	180
1e90474c	181	static int prio_tune(struct Qdisc sch, struct nlattr opt)
1da177e4 LT	182	{
1da177e4 LT	183	struct prio_sched_data *q = qdisc_priv(sch);
d62733c8	184	struct tc_prio_qopt *qopt;
1da177e4 LT	185	int i;
1da177e4 LT	186
1d8ae3fd DM	187	if (nla_len(opt) < sizeof(*qopt))
	188	return -EINVAL;
	189	qopt = nla_data(opt);
d62733c8	190
1d8ae3fd	191	if (qopt->bands > TCQ_PRIO_BANDS \|\| qopt->bands < 2)
1da177e4 LT	192	return -EINVAL;
	193
	194	for (i=0; i<=TC_PRIO_MAX; i++) {
1d8ae3fd	195	if (qopt->priomap[i] >= qopt->bands)
1da177e4 LT	196	return -EINVAL;
	197	}
	198
	199	sch_tree_lock(sch);
1d8ae3fd	200	q->bands = qopt->bands;
1da177e4 LT	201	memcpy(q->prio2band, qopt->priomap, TC_PRIO_MAX+1);
	202
	203	for (i=q->bands; i<TCQ_PRIO_BANDS; i++) {
	204	struct Qdisc *child = xchg(&q->queues[i], &noop_qdisc);
5e50da01 PM	205	if (child != &noop_qdisc) {
5e50da01 PM	206	qdisc_tree_decrease_qlen(child, child->q.qlen);
1da177e4	207	qdisc_destroy(child);
5e50da01	208	}
1da177e4 LT	209	}
	210	sch_tree_unlock(sch);
	211
dd914b40 AA	212	for (i=0; i<q->bands; i++) {
dd914b40 AA	213	if (q->queues[i] == &noop_qdisc) {
1da177e4	214	struct Qdisc *child;
5ce2d488	215	child = qdisc_create_dflt(qdisc_dev(sch), sch->dev_queue,
bb949fbd	216	&pfifo_qdisc_ops,
9f9afec4	217	TC_H_MAKE(sch->handle, i + 1));
1da177e4 LT	218	if (child) {
1da177e4 LT	219	sch_tree_lock(sch);
dd914b40	220	child = xchg(&q->queues[i], child);
1da177e4	221
5e50da01 PM	222	if (child != &noop_qdisc) {
	223	qdisc_tree_decrease_qlen(child,
	224	child->q.qlen);
1da177e4	225	qdisc_destroy(child);
5e50da01	226	}
1da177e4 LT	227	sch_tree_unlock(sch);
	228	}
	229	}
	230	}
	231	return 0;
	232	}
	233
1e90474c	234	static int prio_init(struct Qdisc sch, struct nlattr opt)
1da177e4 LT	235	{
	236	struct prio_sched_data *q = qdisc_priv(sch);
	237	int i;
	238
	239	for (i=0; i<TCQ_PRIO_BANDS; i++)
	240	q->queues[i] = &noop_qdisc;
	241
	242	if (opt == NULL) {
	243	return -EINVAL;
	244	} else {
	245	int err;
	246
	247	if ((err= prio_tune(sch, opt)) != 0)
	248	return err;
	249	}
	250	return 0;
	251	}
	252
	253	static int prio_dump(struct Qdisc sch, struct sk_buff skb)
	254	{
	255	struct prio_sched_data *q = qdisc_priv(sch);
27a884dc	256	unsigned char *b = skb_tail_pointer(skb);
1e90474c	257	struct nlattr *nest;
1da177e4 LT	258	struct tc_prio_qopt opt;
	259
	260	opt.bands = q->bands;
	261	memcpy(&opt.priomap, q->prio2band, TC_PRIO_MAX+1);
d62733c8	262
1e90474c PM	263	nest = nla_nest_compat_start(skb, TCA_OPTIONS, sizeof(opt), &opt);
	264	if (nest == NULL)
	265	goto nla_put_failure;
1e90474c	266	nla_nest_compat_end(skb, nest);
d62733c8	267
1da177e4 LT	268	return skb->len;
1da177e4 LT	269
1e90474c	270	nla_put_failure:
dc5fc579	271	nlmsg_trim(skb, b);
1da177e4 LT	272	return -1;
	273	}
	274
	275	static int prio_graft(struct Qdisc sch, unsigned long arg, struct Qdisc new,
	276	struct Qdisc **old)
	277	{
	278	struct prio_sched_data *q = qdisc_priv(sch);
	279	unsigned long band = arg - 1;
	280
	281	if (band >= q->bands)
	282	return -EINVAL;
	283
	284	if (new == NULL)
	285	new = &noop_qdisc;
	286
	287	sch_tree_lock(sch);
	288	*old = q->queues[band];
	289	q->queues[band] = new;
5e50da01	290	qdisc_tree_decrease_qlen(old, (old)->q.qlen);
1da177e4 LT	291	qdisc_reset(*old);
	292	sch_tree_unlock(sch);
	293
	294	return 0;
	295	}
	296
	297	static struct Qdisc *
	298	prio_leaf(struct Qdisc *sch, unsigned long arg)
	299	{
	300	struct prio_sched_data *q = qdisc_priv(sch);
	301	unsigned long band = arg - 1;
	302
	303	if (band >= q->bands)
	304	return NULL;
	305
	306	return q->queues[band];
	307	}
	308
	309	static unsigned long prio_get(struct Qdisc *sch, u32 classid)
	310	{
	311	struct prio_sched_data *q = qdisc_priv(sch);
	312	unsigned long band = TC_H_MIN(classid);
	313
	314	if (band - 1 >= q->bands)
	315	return 0;
	316	return band;
	317	}
	318
	319	static unsigned long prio_bind(struct Qdisc *sch, unsigned long parent, u32 classid)
	320	{
	321	return prio_get(sch, classid);
	322	}
	323
	324
	325	static void prio_put(struct Qdisc *q, unsigned long cl)
	326	{
	327	return;
	328	}
	329
1e90474c	330	static int prio_change(struct Qdisc sch, u32 handle, u32 parent, struct nlattr tca, unsigned long arg)
1da177e4 LT	331	{
	332	unsigned long cl = *arg;
	333	struct prio_sched_data *q = qdisc_priv(sch);
	334
	335	if (cl - 1 > q->bands)
	336	return -ENOENT;
	337	return 0;
	338	}
	339
	340	static int prio_delete(struct Qdisc *sch, unsigned long cl)
	341	{
	342	struct prio_sched_data *q = qdisc_priv(sch);
	343	if (cl - 1 > q->bands)
	344	return -ENOENT;
	345	return 0;
	346	}
	347
	348
	349	static int prio_dump_class(struct Qdisc sch, unsigned long cl, struct sk_buff skb,
	350	struct tcmsg *tcm)
	351	{
	352	struct prio_sched_data *q = qdisc_priv(sch);
	353
	354	if (cl - 1 > q->bands)
	355	return -ENOENT;
	356	tcm->tcm_handle \|= TC_H_MIN(cl);
	357	if (q->queues[cl-1])
	358	tcm->tcm_info = q->queues[cl-1]->handle;
	359	return 0;
	360	}
	361
2cf6c36c JP	362	static int prio_dump_class_stats(struct Qdisc *sch, unsigned long cl,
	363	struct gnet_dump *d)
	364	{
	365	struct prio_sched_data *q = qdisc_priv(sch);
	366	struct Qdisc *cl_q;
	367
	368	cl_q = q->queues[cl - 1];
	369	if (gnet_stats_copy_basic(d, &cl_q->bstats) < 0 \|\|
	370	gnet_stats_copy_queue(d, &cl_q->qstats) < 0)
	371	return -1;
	372
	373	return 0;
	374	}
	375
1da177e4 LT	376	static void prio_walk(struct Qdisc sch, struct qdisc_walker arg)
	377	{
	378	struct prio_sched_data *q = qdisc_priv(sch);
	379	int prio;
	380
	381	if (arg->stop)
	382	return;
	383
	384	for (prio = 0; prio < q->bands; prio++) {
	385	if (arg->count < arg->skip) {
	386	arg->count++;
	387	continue;
	388	}
	389	if (arg->fn(sch, prio+1, arg) < 0) {
	390	arg->stop = 1;
	391	break;
	392	}
	393	arg->count++;
	394	}
	395	}
	396
	397	static struct tcf_proto ** prio_find_tcf(struct Qdisc *sch, unsigned long cl)
	398	{
	399	struct prio_sched_data *q = qdisc_priv(sch);
	400
	401	if (cl)
	402	return NULL;
	403	return &q->filter_list;
	404	}
	405
20fea08b	406	static const struct Qdisc_class_ops prio_class_ops = {
1da177e4 LT	407	.graft = prio_graft,
	408	.leaf = prio_leaf,
	409	.get = prio_get,
	410	.put = prio_put,
	411	.change = prio_change,
	412	.delete = prio_delete,
	413	.walk = prio_walk,
	414	.tcf_chain = prio_find_tcf,
	415	.bind_tcf = prio_bind,
	416	.unbind_tcf = prio_put,
	417	.dump = prio_dump_class,
2cf6c36c	418	.dump_stats = prio_dump_class_stats,
1da177e4 LT	419	};
1da177e4 LT	420
20fea08b	421	static struct Qdisc_ops prio_qdisc_ops __read_mostly = {
1da177e4 LT	422	.next = NULL,
	423	.cl_ops = &prio_class_ops,
	424	.id = "prio",
	425	.priv_size = sizeof(struct prio_sched_data),
	426	.enqueue = prio_enqueue,
	427	.dequeue = prio_dequeue,
	428	.requeue = prio_requeue,
	429	.drop = prio_drop,
	430	.init = prio_init,
	431	.reset = prio_reset,
	432	.destroy = prio_destroy,
	433	.change = prio_tune,
	434	.dump = prio_dump,
	435	.owner = THIS_MODULE,
	436	};
	437
	438	static int __init prio_module_init(void)
	439	{
1d8ae3fd	440	return register_qdisc(&prio_qdisc_ops);
1da177e4 LT	441	}
1da177e4 LT	442
10297b99	443	static void __exit prio_module_exit(void)
1da177e4 LT	444	{
	445	unregister_qdisc(&prio_qdisc_ops);
	446	}
	447
	448	module_init(prio_module_init)
	449	module_exit(prio_module_exit)
	450
	451	MODULE_LICENSE("GPL");