cls_rsvp.h

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	while (i-- > 0) {
		u32 h;
		if ((data->hgenerator += 0x10000) == 0)
			data->hgenerator = 0x10000;
		h = data->hgenerator|salt;
		if (rsvp_get(tp, h) == 0)
			return h;
	}
	return 0;
}

static int tunnel_bts(struct rsvp_head *data)
{
	int n = data->tgenerator>>5;
	u32 b = 1<<(data->tgenerator&0x1F);
	
	if (data->tmap[n]&b)
		return 0;
	data->tmap[n] |= b;
	return 1;
}

static void tunnel_recycle(struct rsvp_head *data)
{
	struct rsvp_session **sht = data->ht;
	u32 tmap[256/32];
	int h1, h2;

	memset(tmap, 0, sizeof(tmap));

	for (h1=0; h1<256; h1++) {
		struct rsvp_session *s;
		for (s = sht[h1]; s; s = s->next) {
			for (h2=0; h2<=16; h2++) {
				struct rsvp_filter *f;

				for (f = s->ht[h2]; f; f = f->next) {
					if (f->tunnelhdr == 0)
						continue;
					data->tgenerator = f->res.classid;
					tunnel_bts(data);
				}
			}
		}
	}

	memcpy(data->tmap, tmap, sizeof(tmap));
}

static u32 gen_tunnel(struct rsvp_head *data)
{
	int i, k;

	for (k=0; k<2; k++) {
		for (i=255; i>0; i--) {
			if (++data->tgenerator == 0)
				data->tgenerator = 1;
			if (tunnel_bts(data))
				return data->tgenerator;
		}
		tunnel_recycle(data);
	}
	return 0;
}

static int rsvp_change(struct tcf_proto *tp, unsigned long base,
		       u32 handle,
		       struct rtattr **tca,
		       unsigned long *arg)
{
	struct rsvp_head *data = tp->root;
	struct rsvp_filter *f, **fp;
	struct rsvp_session *s, **sp;
	struct tc_rsvp_pinfo *pinfo = NULL;
	struct rtattr *opt = tca[TCA_OPTIONS-1];
	struct rtattr *tb[TCA_RSVP_MAX];
	unsigned h1, h2;
	u32 *dst;
	int err;

	if (opt == NULL)
		return handle ? -EINVAL : 0;

	if (rtattr_parse(tb, TCA_RSVP_MAX, RTA_DATA(opt), RTA_PAYLOAD(opt)) < 0)
		return -EINVAL;

	if ((f = (struct rsvp_filter*)*arg) != NULL) {
		/* Node exists: adjust only classid */

		if (f->handle != handle && handle)
			return -EINVAL;
		if (tb[TCA_RSVP_CLASSID-1]) {
			unsigned long cl;

			f->res.classid = *(u32*)RTA_DATA(tb[TCA_RSVP_CLASSID-1]);
			cl = cls_set_class(tp, &f->res.class, tp->q->ops->cl_ops->bind_tcf(tp->q, base, f->res.classid));
			if (cl)
				tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);
		}
#ifdef CONFIG_NET_CLS_POLICE
		if (tb[TCA_RSVP_POLICE-1]) {
			struct tcf_police *police = tcf_police_locate(tb[TCA_RSVP_POLICE-1], tca[TCA_RATE-1]);

			tcf_tree_lock(tp);
			police = xchg(&f->police, police);
			tcf_tree_unlock(tp);

			tcf_police_release(police);
		}
#endif
		return 0;
	}

	/* Now more serious part... */
	if (handle)
		return -EINVAL;
	if (tb[TCA_RSVP_DST-1] == NULL)
		return -EINVAL;

	f = kmalloc(sizeof(struct rsvp_filter), GFP_KERNEL);
	if (f == NULL)
		return -ENOBUFS;

	memset(f, 0, sizeof(*f));
	h2 = 16;
	if (tb[TCA_RSVP_SRC-1]) {
		err = -EINVAL;
		if (RTA_PAYLOAD(tb[TCA_RSVP_SRC-1]) != sizeof(f->src))
			goto errout;
		memcpy(f->src, RTA_DATA(tb[TCA_RSVP_SRC-1]), sizeof(f->src));
		h2 = hash_src(f->src);
	}
	if (tb[TCA_RSVP_PINFO-1]) {
		err = -EINVAL;
		if (RTA_PAYLOAD(tb[TCA_RSVP_PINFO-1]) < sizeof(struct tc_rsvp_pinfo))
			goto errout;
		pinfo = RTA_DATA(tb[TCA_RSVP_PINFO-1]);
		f->spi = pinfo->spi;
		f->tunnelhdr = pinfo->tunnelhdr;
	}
	if (tb[TCA_RSVP_CLASSID-1]) {
		err = -EINVAL;
		if (RTA_PAYLOAD(tb[TCA_RSVP_CLASSID-1]) != 4)
			goto errout;
		f->res.classid = *(u32*)RTA_DATA(tb[TCA_RSVP_CLASSID-1]);
	}

	err = -EINVAL;
	if (RTA_PAYLOAD(tb[TCA_RSVP_DST-1]) != sizeof(f->src))
		goto errout;
	dst = RTA_DATA(tb[TCA_RSVP_DST-1]);
	h1 = hash_dst(dst, pinfo ? pinfo->protocol : 0, pinfo ? pinfo->tunnelid : 0);

	err = -ENOMEM;
	if ((f->handle = gen_handle(tp, h1 | (h2<<8))) == 0)
		goto errout;

	if (f->tunnelhdr) {
		err = -EINVAL;
		if (f->res.classid > 255)
			goto errout;

		err = -ENOMEM;
		if (f->res.classid == 0 &&
		    (f->res.classid = gen_tunnel(data)) == 0)
			goto errout;
	}

	for (sp = &data->ht[h1]; (s=*sp) != NULL; sp = &s->next) {
		if (dst[RSVP_DST_LEN-1] == s->dst[RSVP_DST_LEN-1] &&
		    pinfo->protocol == s->protocol &&
		    memcmp(&pinfo->dpi, &s->dpi, sizeof(s->dpi)) == 0
#if RSVP_DST_LEN == 4
		    && dst[0] == s->dst[0]
		    && dst[1] == s->dst[1]
		    && dst[2] == s->dst[2]
#endif
		    && pinfo->tunnelid == s->tunnelid) {

insert:
			/* OK, we found appropriate session */

			fp = &s->ht[h2];

			f->sess = s;
			if (f->tunnelhdr == 0)
				cls_set_class(tp, &f->res.class, tp->q->ops->cl_ops->bind_tcf(tp->q, base, f->res.classid));
#ifdef CONFIG_NET_CLS_POLICE
			if (tb[TCA_RSVP_POLICE-1])
				f->police = tcf_police_locate(tb[TCA_RSVP_POLICE-1], tca[TCA_RATE-1]);
#endif

			for (fp = &s->ht[h2]; *fp; fp = &(*fp)->next)
				if (((*fp)->spi.mask&f->spi.mask) != f->spi.mask)
					break;
			f->next = *fp;
			wmb();
			*fp = f;

			*arg = (unsigned long)f;
			return 0;
		}
	}

	/* No session found. Create new one. */

	err = -ENOBUFS;
	s = kmalloc(sizeof(struct rsvp_session), GFP_KERNEL);
	if (s == NULL)
		goto errout;
	memset(s, 0, sizeof(*s));
	memcpy(s->dst, dst, sizeof(s->dst));
	s->dpi = pinfo->dpi;
	s->protocol = pinfo->protocol;
	s->tunnelid = pinfo->tunnelid;
	for (sp = &data->ht[h1]; *sp; sp = &(*sp)->next) {
		if (((*sp)->dpi.mask&s->dpi.mask) != s->dpi.mask)
			break;
	}
	s->next = *sp;
	wmb();
	*sp = s;
	
	goto insert;

errout:
	if (f)
		kfree(f);
	return err;
}

static void rsvp_walk(struct tcf_proto *tp, struct tcf_walker *arg)
{
	struct rsvp_head *head = tp->root;
	unsigned h, h1;

	if (arg->stop)
		return;

	for (h = 0; h < 256; h++) {
		struct rsvp_session *s;

		for (s = head->ht[h]; s; s = s->next) {
			for (h1 = 0; h1 <= 16; h1++) {
				struct rsvp_filter *f;

				for (f = s->ht[h1]; f; f = f->next) {
					if (arg->count < arg->skip) {
						arg->count++;
						continue;
					}
					if (arg->fn(tp, (unsigned long)f, arg) < 0) {
						arg->stop = 1;
						break;
					}
					arg->count++;
				}
			}
		}
	}
}

#ifdef CONFIG_RTNETLINK
static int rsvp_dump(struct tcf_proto *tp, unsigned long fh,
		     struct sk_buff *skb, struct tcmsg *t)
{
	struct rsvp_filter *f = (struct rsvp_filter*)fh;
	struct rsvp_session *s;
	unsigned char	 *b = skb->tail;
	struct rtattr *rta;
	struct tc_rsvp_pinfo pinfo;

	if (f == NULL)
		return skb->len;
	s = f->sess;

	t->tcm_handle = f->handle;


	rta = (struct rtattr*)b;
	RTA_PUT(skb, TCA_OPTIONS, 0, NULL);

	RTA_PUT(skb, TCA_RSVP_DST, sizeof(s->dst), &s->dst);
	pinfo.dpi = s->dpi;
	pinfo.spi = f->spi;
	pinfo.protocol = s->protocol;
	pinfo.tunnelid = s->tunnelid;
	pinfo.tunnelhdr = f->tunnelhdr;
	RTA_PUT(skb, TCA_RSVP_PINFO, sizeof(pinfo), &pinfo);
	if (f->res.classid)
		RTA_PUT(skb, TCA_RSVP_CLASSID, 4, &f->res.classid);
	if (((f->handle>>8)&0xFF) != 16)
		RTA_PUT(skb, TCA_RSVP_SRC, sizeof(f->src), f->src);
#ifdef CONFIG_NET_CLS_POLICE
	if (f->police) {
		struct rtattr * p_rta = (struct rtattr*)skb->tail;

		RTA_PUT(skb, TCA_RSVP_POLICE, 0, NULL);

		if (tcf_police_dump(skb, f->police) < 0)
			goto rtattr_failure;

		p_rta->rta_len = skb->tail - (u8*)p_rta;
	}
#endif

	rta->rta_len = skb->tail - b;
#ifdef CONFIG_NET_CLS_POLICE
	if (f->police) {
		if (qdisc_copy_stats(skb, &f->police->stats))
			goto rtattr_failure;
	}
#endif
	return skb->len;

rtattr_failure:
	skb_trim(skb, b - skb->data);
	return -1;
}
#endif

struct tcf_proto_ops RSVP_OPS = {
	NULL,
	RSVP_ID,
	rsvp_classify,
	rsvp_init,
	rsvp_destroy,

	rsvp_get,
	rsvp_put,
	rsvp_change,
	rsvp_delete,
	rsvp_walk,
#ifdef CONFIG_RTNETLINK
	rsvp_dump
#else
	NULL
#endif
};

#ifdef MODULE
int init_module(void)
{
	return register_tcf_proto_ops(&RSVP_OPS);
}

void cleanup_module(void) 
{
	unregister_tcf_proto_ops(&RSVP_OPS);
}
#endif