Commit 73ca4918 authored by Patrick McHardy's avatar Patrick McHardy Committed by David S. Miller
Browse files

[NET_SCHED]: act_api: qdisc internal reclassify support 



The behaviour of NET_CLS_POLICE for TC_POLICE_RECLASSIFY was to return
it to the qdisc, which could handle it internally or ignore it. With
NET_CLS_ACT however, tc_classify starts over at the first classifier
and never returns it to the qdisc. This makes it impossible to support
qdisc-internal reclassification, which in turn makes it impossible to
remove the old NET_CLS_POLICE code without breaking compatibility since
we have two qdiscs (CBQ and ATM) that support this.

This patch adds a tc_classify_compat function that handles
reclassification the old way and changes CBQ and ATM to use it.

This again is of course not fully backwards compatible with the previous
NET_CLS_ACT behaviour. Unfortunately there is no way to fully maintain
compatibility *and* support qdisc internal reclassification with
NET_CLS_ACT, but this seems like the better choice over keeping the two
incompatible options around forever.

Signed-off-by: default avatarPatrick McHardy <kaber@trash.net>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent f6853e2d

include/net/pkt_sched.h

+3 −1
Original line number Diff line number Diff line
@@ -89,6 +89,8 @@ static inline void qdisc_run(struct net_device *dev) 
		__qdisc_run(dev);

}



extern int tc_classify_compat(struct sk_buff *skb, struct tcf_proto *tp,

			      struct tcf_result *res);

extern int tc_classify(struct sk_buff *skb, struct tcf_proto *tp,

		       struct tcf_result *res);

include/net/sch_generic.h

+1 −1
Original line number Diff line number Diff line
@@ -290,7 +290,7 @@ static inline int qdisc_reshape_fail(struct sk_buff *skb, struct Qdisc *sch) 
{

	sch->qstats.drops++;



#ifdef CONFIG_NET_CLS_POLICE

#if defined(CONFIG_NET_CLS_ACT) || defined(CONFIG_NET_CLS_POLICE)

	if (sch->reshape_fail == NULL || sch->reshape_fail(skb, sch))

		goto drop;

net/sched/sch_api.c

+38 −29
Original line number Diff line number Diff line
@@ -1145,47 +1145,57 @@ static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb) 
   to this qdisc, (optionally) tests for protocol and asks

   specific classifiers.

 */

int tc_classify_compat(struct sk_buff *skb, struct tcf_proto *tp,

		       struct tcf_result *res)

{

	__be16 protocol = skb->protocol;

	int err = 0;



	for (; tp; tp = tp->next) {

		if ((tp->protocol == protocol ||

		     tp->protocol == htons(ETH_P_ALL)) &&

		    (err = tp->classify(skb, tp, res)) >= 0) {

#ifdef CONFIG_NET_CLS_ACT

			if (err != TC_ACT_RECLASSIFY && skb->tc_verd)

				skb->tc_verd = SET_TC_VERD(skb->tc_verd, 0);

#endif

			return err;

		}

	}

	return -1;

}

EXPORT_SYMBOL(tc_classify_compat);



int tc_classify(struct sk_buff *skb, struct tcf_proto *tp,

		struct tcf_result *res)

{

	int err = 0;

	__be16 protocol = skb->protocol;

	__be16 protocol;

#ifdef CONFIG_NET_CLS_ACT

	struct tcf_proto *otp = tp;

reclassify:

#endif

	protocol = skb->protocol;



	for ( ; tp; tp = tp->next) {

		if ((tp->protocol == protocol ||

			tp->protocol == htons(ETH_P_ALL)) &&

			(err = tp->classify(skb, tp, res)) >= 0) {

	err = tc_classify_compat(skb, tp, res);

#ifdef CONFIG_NET_CLS_ACT

			if ( TC_ACT_RECLASSIFY == err) {

				__u32 verd = (__u32) G_TC_VERD(skb->tc_verd);

	if (err == TC_ACT_RECLASSIFY) {

		u32 verd = G_TC_VERD(skb->tc_verd);

		tp = otp;



				if (MAX_REC_LOOP < verd++) {

					printk("rule prio %d protocol %02x reclassify is buggy packet dropped\n",

		if (verd++ >= MAX_REC_LOOP) {

			printk("rule prio %u protocol %02x reclassify loop, "

			       "packet dropped\n",

			       tp->prio&0xffff, ntohs(tp->protocol));

			return TC_ACT_SHOT;

		}

		skb->tc_verd = SET_TC_VERD(skb->tc_verd, verd);

		goto reclassify;

			} else {

				if (skb->tc_verd)

					skb->tc_verd = SET_TC_VERD(skb->tc_verd,0);

				return err;

	}

#else



			return err;

#endif

	return err;

}



	}

	return -1;

}

EXPORT_SYMBOL(tc_classify);



void tcf_destroy(struct tcf_proto *tp)

{
@@ -1252,4 +1262,3 @@ EXPORT_SYMBOL(qdisc_get_rtab); 
EXPORT_SYMBOL(qdisc_put_rtab);

EXPORT_SYMBOL(register_qdisc);

EXPORT_SYMBOL(unregister_qdisc);
 
EXPORT_SYMBOL(tc_classify);

net/sched/sch_atm.c

+9 −2
Original line number Diff line number Diff line
@@ -396,7 +396,8 @@ static int atm_tc_enqueue(struct sk_buff *skb, struct Qdisc *sch) 
	    !(flow = (struct atm_flow_data *)atm_tc_get(sch, skb->priority)))

		for (flow = p->flows; flow; flow = flow->next)

			if (flow->filter_list) {

				result = tc_classify(skb, flow->filter_list,

				result = tc_classify_compat(skb,

							    flow->filter_list,

							    &res);

				if (result < 0)

					continue;
@@ -420,6 +421,12 @@ static int atm_tc_enqueue(struct sk_buff *skb, struct Qdisc *sch) 
		case TC_ACT_SHOT:

			kfree_skb(skb);

			goto drop;

		case TC_POLICE_RECLASSIFY:

			if (flow->excess)

				flow = flow->excess;

			else

				ATM_SKB(skb)->atm_options |= ATM_ATMOPT_CLP;

			break;

		}

#elif defined(CONFIG_NET_CLS_POLICE)

		switch (result) {

net/sched/sch_cbq.c

+21 −18
Original line number Diff line number Diff line
@@ -82,7 +82,7 @@ struct cbq_class 
	unsigned char		priority2;	/* priority to be used after overlimit */

	unsigned char		ewma_log;	/* time constant for idle time calculation */

	unsigned char		ovl_strategy;

#ifdef CONFIG_NET_CLS_POLICE

#if defined(CONFIG_NET_CLS_ACT) || defined(CONFIG_NET_CLS_POLICE)

	unsigned char		police;

#endif
@@ -154,7 +154,7 @@ struct cbq_sched_data 
	struct cbq_class	*active[TC_CBQ_MAXPRIO+1];	/* List of all classes

								   with backlog */



#ifdef CONFIG_NET_CLS_POLICE

#if defined(CONFIG_NET_CLS_ACT) || defined(CONFIG_NET_CLS_POLICE)

	struct cbq_class	*rx_class;

#endif

	struct cbq_class	*tx_class;
@@ -196,7 +196,7 @@ cbq_class_lookup(struct cbq_sched_data *q, u32 classid) 
	return NULL;

}



#ifdef CONFIG_NET_CLS_POLICE

#if defined(CONFIG_NET_CLS_ACT) || defined(CONFIG_NET_CLS_POLICE)



static struct cbq_class *

cbq_reclassify(struct sk_buff *skb, struct cbq_class *this)
@@ -247,7 +247,8 @@ cbq_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr) 
		/*

		 * Step 2+n. Apply classifier.

		 */

		if (!head->filter_list || (result = tc_classify(skb, head->filter_list, &res)) < 0)

		if (!head->filter_list ||

		    (result = tc_classify_compat(skb, head->filter_list, &res)) < 0)

			goto fallback;



		if ((cl = (void*)res.class) == NULL) {
@@ -267,6 +268,8 @@ cbq_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr) 
			*qerr = NET_XMIT_SUCCESS;

		case TC_ACT_SHOT:

			return NULL;

		case TC_ACT_RECLASSIFY:

			return cbq_reclassify(skb, cl);

		}

#elif defined(CONFIG_NET_CLS_POLICE)

		switch (result) {
@@ -389,7 +392,7 @@ cbq_enqueue(struct sk_buff *skb, struct Qdisc *sch) 
	int ret;

	struct cbq_class *cl = cbq_classify(skb, sch, &ret);



#ifdef CONFIG_NET_CLS_POLICE

#if defined(CONFIG_NET_CLS_ACT) || defined(CONFIG_NET_CLS_POLICE)

	q->rx_class = cl;

#endif

	if (cl == NULL) {
@@ -399,7 +402,7 @@ cbq_enqueue(struct sk_buff *skb, struct Qdisc *sch) 
		return ret;

	}



#ifdef CONFIG_NET_CLS_POLICE

#if defined(CONFIG_NET_CLS_ACT) || defined(CONFIG_NET_CLS_POLICE)

	cl->q->__parent = sch;

#endif

	if ((ret = cl->q->enqueue(skb, cl->q)) == NET_XMIT_SUCCESS) {
@@ -434,7 +437,7 @@ cbq_requeue(struct sk_buff *skb, struct Qdisc *sch) 


	cbq_mark_toplevel(q, cl);



#ifdef CONFIG_NET_CLS_POLICE

#if defined(CONFIG_NET_CLS_ACT) || defined(CONFIG_NET_CLS_POLICE)

	q->rx_class = cl;

	cl->q->__parent = sch;

#endif
@@ -670,7 +673,7 @@ static enum hrtimer_restart cbq_undelay(struct hrtimer *timer) 
}





#ifdef CONFIG_NET_CLS_POLICE

#if defined(CONFIG_NET_CLS_ACT) || defined(CONFIG_NET_CLS_POLICE)



static int cbq_reshape_fail(struct sk_buff *skb, struct Qdisc *child)

{
@@ -1364,7 +1367,7 @@ static int cbq_set_overlimit(struct cbq_class *cl, struct tc_cbq_ovl *ovl) 
	return 0;

}



#ifdef CONFIG_NET_CLS_POLICE

#if defined(CONFIG_NET_CLS_ACT) || defined(CONFIG_NET_CLS_POLICE)

static int cbq_set_police(struct cbq_class *cl, struct tc_cbq_police *p)

{

	cl->police = p->police;
@@ -1532,7 +1535,7 @@ rtattr_failure: 
	return -1;

}



#ifdef CONFIG_NET_CLS_POLICE

#if defined(CONFIG_NET_CLS_ACT) || defined(CONFIG_NET_CLS_POLICE)

static __inline__ int cbq_dump_police(struct sk_buff *skb, struct cbq_class *cl)

{

	unsigned char *b = skb_tail_pointer(skb);
@@ -1558,7 +1561,7 @@ static int cbq_dump_attr(struct sk_buff *skb, struct cbq_class *cl) 
	    cbq_dump_rate(skb, cl) < 0 ||

	    cbq_dump_wrr(skb, cl) < 0 ||

	    cbq_dump_ovl(skb, cl) < 0 ||

#ifdef CONFIG_NET_CLS_POLICE

#if defined(CONFIG_NET_CLS_ACT) || defined(CONFIG_NET_CLS_POLICE)

	    cbq_dump_police(skb, cl) < 0 ||

#endif

	    cbq_dump_fopt(skb, cl) < 0)
@@ -1653,7 +1656,7 @@ static int cbq_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new, 
						     cl->classid)) == NULL)

				return -ENOBUFS;

		} else {

#ifdef CONFIG_NET_CLS_POLICE

#if defined(CONFIG_NET_CLS_ACT) || defined(CONFIG_NET_CLS_POLICE)

			if (cl->police == TC_POLICE_RECLASSIFY)

				new->reshape_fail = cbq_reshape_fail;

#endif
@@ -1718,7 +1721,7 @@ cbq_destroy(struct Qdisc* sch) 
	struct cbq_class *cl;

	unsigned h;



#ifdef CONFIG_NET_CLS_POLICE

#if defined(CONFIG_NET_CLS_ACT) || defined(CONFIG_NET_CLS_POLICE)

	q->rx_class = NULL;

#endif

	/*
@@ -1747,7 +1750,7 @@ static void cbq_put(struct Qdisc *sch, unsigned long arg) 
	struct cbq_class *cl = (struct cbq_class*)arg;



	if (--cl->refcnt == 0) {

#ifdef CONFIG_NET_CLS_POLICE

#if defined(CONFIG_NET_CLS_ACT) || defined(CONFIG_NET_CLS_POLICE)

		struct cbq_sched_data *q = qdisc_priv(sch);



		spin_lock_bh(&sch->dev->queue_lock);
@@ -1795,7 +1798,7 @@ cbq_change_class(struct Qdisc *sch, u32 classid, u32 parentid, struct rtattr **t 
	    RTA_PAYLOAD(tb[TCA_CBQ_WRROPT-1]) < sizeof(struct tc_cbq_wrropt))

			return -EINVAL;



#ifdef CONFIG_NET_CLS_POLICE

#if defined(CONFIG_NET_CLS_ACT) || defined(CONFIG_NET_CLS_POLICE)

	if (tb[TCA_CBQ_POLICE-1] &&

	    RTA_PAYLOAD(tb[TCA_CBQ_POLICE-1]) < sizeof(struct tc_cbq_police))

			return -EINVAL;
@@ -1838,7 +1841,7 @@ cbq_change_class(struct Qdisc *sch, u32 classid, u32 parentid, struct rtattr **t 
		if (tb[TCA_CBQ_OVL_STRATEGY-1])

			cbq_set_overlimit(cl, RTA_DATA(tb[TCA_CBQ_OVL_STRATEGY-1]));



#ifdef CONFIG_NET_CLS_POLICE

#if defined(CONFIG_NET_CLS_ACT) || defined(CONFIG_NET_CLS_POLICE)

		if (tb[TCA_CBQ_POLICE-1])

			cbq_set_police(cl, RTA_DATA(tb[TCA_CBQ_POLICE-1]));

#endif
@@ -1931,7 +1934,7 @@ cbq_change_class(struct Qdisc *sch, u32 classid, u32 parentid, struct rtattr **t 
	cl->overlimit = cbq_ovl_classic;

	if (tb[TCA_CBQ_OVL_STRATEGY-1])

		cbq_set_overlimit(cl, RTA_DATA(tb[TCA_CBQ_OVL_STRATEGY-1]));

#ifdef CONFIG_NET_CLS_POLICE

#if defined(CONFIG_NET_CLS_ACT) || defined(CONFIG_NET_CLS_POLICE)

	if (tb[TCA_CBQ_POLICE-1])

		cbq_set_police(cl, RTA_DATA(tb[TCA_CBQ_POLICE-1]));

#endif
@@ -1975,7 +1978,7 @@ static int cbq_delete(struct Qdisc *sch, unsigned long arg) 
		q->tx_class = NULL;

		q->tx_borrowed = NULL;

	}

#ifdef CONFIG_NET_CLS_POLICE

#if defined(CONFIG_NET_CLS_ACT) || defined(CONFIG_NET_CLS_POLICE)

	if (q->rx_class == cl)

		q->rx_class = NULL;

#endif

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