net/sched/sch_atm.c - kernel/msm-4.9 - Gitiles

 /* net/sched/sch_atm.c - ATM VC selection "queueing discipline" */

 /* Written 1998-2000 by Werner Almesberger, EPFL ICA */

 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/init.h>
 #include <linux/string.h>
 #include <linux/errno.h>
 #include <linux/skbuff.h>
 #include <linux/atmdev.h>
 #include <linux/atmclip.h>
 #include <linux/rtnetlink.h>
 #include <linux/file.h>		/* for fput */
 #include <net/netlink.h>
 #include <net/pkt_sched.h>

 extern struct socket *sockfd_lookup(int fd, int *err);	/* @@@ fix this */

 /*
  * The ATM queuing discipline provides a framework for invoking classifiers
  * (aka "filters"), which in turn select classes of this queuing discipline.
  * Each class maps the flow(s) it is handling to a given VC. Multiple classes
  * may share the same VC.
  *
  * When creating a class, VCs are specified by passing the number of the open
  * socket descriptor by which the calling process references the VC. The kernel
  * keeps the VC open at least until all classes using it are removed.
  *
  * In this file, most functions are named atm_tc_* to avoid confusion with all
  * the atm_* in net/atm. This naming convention differs from what's used in the
  * rest of net/sched.
  *
  * Known bugs:
  *  - sometimes messes up the IP stack
  *  - any manipulations besides the few operations described in the README, are
  *    untested and likely to crash the system
  *  - should lock the flow while there is data in the queue (?)
  */

 #define VCC2FLOW(vcc) ((struct atm_flow_data *) ((vcc)->user_back))

 struct atm_flow_data {
 	struct Qdisc		*q;	/* FIFO, TBF, etc. */
 	struct tcf_proto	*filter_list;
 	struct atm_vcc		*vcc;	/* VCC; NULL if VCC is closed */
 	void			(*old_pop)(struct atm_vcc *vcc,
 					   struct sk_buff *skb); /* chaining */
 	struct atm_qdisc_data	*parent;	/* parent qdisc */
 	struct socket		*sock;		/* for closing */
 	u32			classid;	/* x:y type ID */
 	int			ref;		/* reference count */
 	struct gnet_stats_basic_packed	bstats;
 	struct gnet_stats_queue	qstats;
 	struct list_head	list;
 	struct atm_flow_data	*excess;	/* flow for excess traffic;
 						   NULL to set CLP instead */
 	int			hdr_len;
 	unsigned char		hdr[0];		/* header data; MUST BE LAST */
 };

 struct atm_qdisc_data {
 	struct atm_flow_data	link;		/* unclassified skbs go here */
 	struct list_head	flows;		/* NB: "link" is also on this
 						   list */
 	struct tasklet_struct	task;		/* dequeue tasklet */
 };

 /* ------------------------- Class/flow operations ------------------------- */

 static inline struct atm_flow_data *lookup_flow(struct Qdisc *sch, u32 classid)
 {
 	struct atm_qdisc_data *p = qdisc_priv(sch);
 	struct atm_flow_data *flow;

 	list_for_each_entry(flow, &p->flows, list) {
 		if (flow->classid == classid)
 			return flow;
 	}
 	return NULL;
 }

 static int atm_tc_graft(struct Qdisc *sch, unsigned long arg,
 			struct Qdisc *new, struct Qdisc **old)
 {
 	struct atm_qdisc_data *p = qdisc_priv(sch);
 	struct atm_flow_data *flow = (struct atm_flow_data *)arg;

 	pr_debug("atm_tc_graft(sch %p,[qdisc %p],flow %p,new %p,old %p)\n",
 		sch, p, flow, new, old);
 	if (list_empty(&flow->list))
 		return -EINVAL;
 	if (!new)
 		new = &noop_qdisc;
 	*old = flow->q;
 	flow->q = new;
 	if (*old)
 		qdisc_reset(*old);
 	return 0;
 }

 static struct Qdisc *atm_tc_leaf(struct Qdisc *sch, unsigned long cl)
 {
 	struct atm_flow_data *flow = (struct atm_flow_data *)cl;

 	pr_debug("atm_tc_leaf(sch %p,flow %p)\n", sch, flow);
 	return flow ? flow->q : NULL;
 }

 static unsigned long atm_tc_get(struct Qdisc *sch, u32 classid)
 {
 	struct atm_qdisc_data *p __maybe_unused = qdisc_priv(sch);
 	struct atm_flow_data *flow;

 	pr_debug("atm_tc_get(sch %p,[qdisc %p],classid %x)\n", sch, p, classid);
 	flow = lookup_flow(sch, classid);
 	if (flow)
 		flow->ref++;
 	pr_debug("atm_tc_get: flow %p\n", flow);
 	return (unsigned long)flow;
 }

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

 /*
  * atm_tc_put handles all destructions, including the ones that are explicitly
  * requested (atm_tc_destroy, etc.). The assumption here is that we never drop
  * anything that still seems to be in use.
  */
 static void atm_tc_put(struct Qdisc *sch, unsigned long cl)
 {
 	struct atm_qdisc_data *p = qdisc_priv(sch);
 	struct atm_flow_data *flow = (struct atm_flow_data *)cl;

 	pr_debug("atm_tc_put(sch %p,[qdisc %p],flow %p)\n", sch, p, flow);
 	if (--flow->ref)
 		return;
 	pr_debug("atm_tc_put: destroying\n");
 	list_del_init(&flow->list);
 	pr_debug("atm_tc_put: qdisc %p\n", flow->q);
 	qdisc_destroy(flow->q);
 	tcf_destroy_chain(&flow->filter_list);
 	if (flow->sock) {
 		pr_debug("atm_tc_put: f_count %ld\n",
 			file_count(flow->sock->file));
 		flow->vcc->pop = flow->old_pop;
 		sockfd_put(flow->sock);
 	}
 	if (flow->excess)
 		atm_tc_put(sch, (unsigned long)flow->excess);
 	if (flow != &p->link)
 		kfree(flow);
 	/*
 	 * If flow == &p->link, the qdisc no longer works at this point and
 	 * needs to be removed. (By the caller of atm_tc_put.)
 	 */
 }

 static void sch_atm_pop(struct atm_vcc *vcc, struct sk_buff *skb)
 {
 	struct atm_qdisc_data *p = VCC2FLOW(vcc)->parent;

 	pr_debug("sch_atm_pop(vcc %p,skb %p,[qdisc %p])\n", vcc, skb, p);
 	VCC2FLOW(vcc)->old_pop(vcc, skb);
 	tasklet_schedule(&p->task);
 }

 static const u8 llc_oui_ip[] = {
 	0xaa,			/* DSAP: non-ISO */
 	0xaa,			/* SSAP: non-ISO */
 	0x03,			/* Ctrl: Unnumbered Information Command PDU */
 	0x00,			/* OUI: EtherType */
 	0x00, 0x00,
 	0x08, 0x00
 };				/* Ethertype IP (0800) */

 static const struct nla_policy atm_policy[TCA_ATM_MAX + 1] = {
 	[TCA_ATM_FD]		= { .type = NLA_U32 },
 	[TCA_ATM_EXCESS]	= { .type = NLA_U32 },
 };

 static int atm_tc_change(struct Qdisc *sch, u32 classid, u32 parent,
 			 struct nlattr **tca, unsigned long *arg)
 {
 	struct atm_qdisc_data *p = qdisc_priv(sch);
 	struct atm_flow_data *flow = (struct atm_flow_data *)*arg;
 	struct atm_flow_data *excess = NULL;
 	struct nlattr *opt = tca[TCA_OPTIONS];
 	struct nlattr *tb[TCA_ATM_MAX + 1];
 	struct socket *sock;
 	int fd, error, hdr_len;
 	void *hdr;

 	pr_debug("atm_tc_change(sch %p,[qdisc %p],classid %x,parent %x,"
 		"flow %p,opt %p)\n", sch, p, classid, parent, flow, opt);
 	/*
 	 * The concept of parents doesn't apply for this qdisc.
 	 */
 	if (parent && parent != TC_H_ROOT && parent != sch->handle)
 		return -EINVAL;
 	/*
 	 * ATM classes cannot be changed. In order to change properties of the
 	 * ATM connection, that socket needs to be modified directly (via the
 	 * native ATM API. In order to send a flow to a different VC, the old
 	 * class needs to be removed and a new one added. (This may be changed
 	 * later.)
 	 */
 	if (flow)
 		return -EBUSY;
 	if (opt == NULL)
 		return -EINVAL;

 	error = nla_parse_nested(tb, TCA_ATM_MAX, opt, atm_policy);
 	if (error < 0)
 		return error;

 	if (!tb[TCA_ATM_FD])
 		return -EINVAL;
 	fd = nla_get_u32(tb[TCA_ATM_FD]);
 	pr_debug("atm_tc_change: fd %d\n", fd);
 	if (tb[TCA_ATM_HDR]) {
 		hdr_len = nla_len(tb[TCA_ATM_HDR]);
 		hdr = nla_data(tb[TCA_ATM_HDR]);
 	} else {
 		hdr_len = RFC1483LLC_LEN;
 		hdr = NULL;	/* default LLC/SNAP for IP */
 	}
 	if (!tb[TCA_ATM_EXCESS])
 		excess = NULL;
 	else {
 		excess = (struct atm_flow_data *)
 			atm_tc_get(sch, nla_get_u32(tb[TCA_ATM_EXCESS]));
 		if (!excess)
 			return -ENOENT;
 	}
 	pr_debug("atm_tc_change: type %d, payload %d, hdr_len %d\n",
 		 opt->nla_type, nla_len(opt), hdr_len);
 	sock = sockfd_lookup(fd, &error);
 	if (!sock)
 		return error;	/* f_count++ */
 	pr_debug("atm_tc_change: f_count %ld\n", file_count(sock->file));
 	if (sock->ops->family != PF_ATMSVC && sock->ops->family != PF_ATMPVC) {
 		error = -EPROTOTYPE;
 		goto err_out;
 	}
 	/* @@@ should check if the socket is really operational or we'll crash
 	   on vcc->send */
 	if (classid) {
 		if (TC_H_MAJ(classid ^ sch->handle)) {
 			pr_debug("atm_tc_change: classid mismatch\n");
 			error = -EINVAL;
 			goto err_out;
 		}
 	} else {
 		int i;
 		unsigned long cl;

 		for (i = 1; i < 0x8000; i++) {
 			classid = TC_H_MAKE(sch->handle, 0x8000 | i);
 			cl = atm_tc_get(sch, classid);
 			if (!cl)
 				break;
 			atm_tc_put(sch, cl);
 		}
 	}
 	pr_debug("atm_tc_change: new id %x\n", classid);
 	flow = kzalloc(sizeof(struct atm_flow_data) + hdr_len, GFP_KERNEL);
 	pr_debug("atm_tc_change: flow %p\n", flow);
 	if (!flow) {
 		error = -ENOBUFS;
 		goto err_out;
 	}
 	flow->filter_list = NULL;
 	flow->q = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops, classid);
 	if (!flow->q)
 		flow->q = &noop_qdisc;
 	pr_debug("atm_tc_change: qdisc %p\n", flow->q);
 	flow->sock = sock;
 	flow->vcc = ATM_SD(sock);	/* speedup */
 	flow->vcc->user_back = flow;
 	pr_debug("atm_tc_change: vcc %p\n", flow->vcc);
 	flow->old_pop = flow->vcc->pop;
 	flow->parent = p;
 	flow->vcc->pop = sch_atm_pop;
 	flow->classid = classid;
 	flow->ref = 1;
 	flow->excess = excess;
 	list_add(&flow->list, &p->link.list);
 	flow->hdr_len = hdr_len;
 	if (hdr)
 		memcpy(flow->hdr, hdr, hdr_len);
 	else
 		memcpy(flow->hdr, llc_oui_ip, sizeof(llc_oui_ip));
 	*arg = (unsigned long)flow;
 	return 0;
 err_out:
 	if (excess)
 		atm_tc_put(sch, (unsigned long)excess);
 	sockfd_put(sock);
 	return error;
 }

 static int atm_tc_delete(struct Qdisc *sch, unsigned long arg)
 {
 	struct atm_qdisc_data *p = qdisc_priv(sch);
 	struct atm_flow_data *flow = (struct atm_flow_data *)arg;

 	pr_debug("atm_tc_delete(sch %p,[qdisc %p],flow %p)\n", sch, p, flow);
 	if (list_empty(&flow->list))
 		return -EINVAL;
 	if (flow->filter_list || flow == &p->link)
 		return -EBUSY;
 	/*
 	 * Reference count must be 2: one for "keepalive" (set at class
 	 * creation), and one for the reference held when calling delete.
 	 */
 	if (flow->ref < 2) {
 		printk(KERN_ERR "atm_tc_delete: flow->ref == %d\n", flow->ref);
 		return -EINVAL;
 	}
 	if (flow->ref > 2)
 		return -EBUSY;	/* catch references via excess, etc. */
 	atm_tc_put(sch, arg);
 	return 0;
 }

 static void atm_tc_walk(struct Qdisc *sch, struct qdisc_walker *walker)
 {
 	struct atm_qdisc_data *p = qdisc_priv(sch);
 	struct atm_flow_data *flow;

 	pr_debug("atm_tc_walk(sch %p,[qdisc %p],walker %p)\n", sch, p, walker);
 	if (walker->stop)
 		return;
 	list_for_each_entry(flow, &p->flows, list) {
 		if (walker->count >= walker->skip &&
 		    walker->fn(sch, (unsigned long)flow, walker) < 0) {
 			walker->stop = 1;
 			break;
 		}
 		walker->count++;
 	}
 }

 static struct tcf_proto **atm_tc_find_tcf(struct Qdisc *sch, unsigned long cl)
 {
 	struct atm_qdisc_data *p = qdisc_priv(sch);
 	struct atm_flow_data *flow = (struct atm_flow_data *)cl;

 	pr_debug("atm_tc_find_tcf(sch %p,[qdisc %p],flow %p)\n", sch, p, flow);
 	return flow ? &flow->filter_list : &p->link.filter_list;
 }

 /* --------------------------- Qdisc operations ---------------------------- */

 static int atm_tc_enqueue(struct sk_buff *skb, struct Qdisc *sch)
 {
 	struct atm_qdisc_data *p = qdisc_priv(sch);
 	struct atm_flow_data *flow;
 	struct tcf_result res;
 	int result;
 	int ret = NET_XMIT_POLICED;

 	pr_debug("atm_tc_enqueue(skb %p,sch %p,[qdisc %p])\n", skb, sch, p);
 	result = TC_POLICE_OK;	/* be nice to gcc */
 	flow = NULL;
 	if (TC_H_MAJ(skb->priority) != sch->handle ||
 	    !(flow = (struct atm_flow_data *)atm_tc_get(sch, skb->priority))) {
 		list_for_each_entry(flow, &p->flows, list) {
 			if (flow->filter_list) {
 				result = tc_classify_compat(skb,
 							    flow->filter_list,
 							    &res);
 				if (result < 0)
 					continue;
 				flow = (struct atm_flow_data *)res.class;
 				if (!flow)
 					flow = lookup_flow(sch, res.classid);
 				goto done;
 			}
 		}
 		flow = NULL;
 	done:
 		;
 	}
 	if (!flow)
 		flow = &p->link;
 	else {
 		if (flow->vcc)
 			ATM_SKB(skb)->atm_options = flow->vcc->atm_options;
 		/*@@@ looks good ... but it's not supposed to work :-) */
 #ifdef CONFIG_NET_CLS_ACT
 		switch (result) {
 		case TC_ACT_QUEUED:
 		case TC_ACT_STOLEN:
 			kfree_skb(skb);
 			return NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
 		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;
 		}
 #endif
 	}

 	ret = qdisc_enqueue(skb, flow->q);
 	if (ret != NET_XMIT_SUCCESS) {
 drop: __maybe_unused
 		if (net_xmit_drop_count(ret)) {
 			sch->qstats.drops++;
 			if (flow)
 				flow->qstats.drops++;
 		}
 		return ret;
 	}
 	sch->bstats.bytes += qdisc_pkt_len(skb);
 	sch->bstats.packets++;
 	flow->bstats.bytes += qdisc_pkt_len(skb);
 	flow->bstats.packets++;
 	/*
 	 * Okay, this may seem weird. We pretend we've dropped the packet if
 	 * it goes via ATM. The reason for this is that the outer qdisc
 	 * expects to be able to q->dequeue the packet later on if we return
 	 * success at this place. Also, sch->q.qdisc needs to reflect whether
 	 * there is a packet egligible for dequeuing or not. Note that the
 	 * statistics of the outer qdisc are necessarily wrong because of all
 	 * this. There's currently no correct solution for this.
 	 */
 	if (flow == &p->link) {
 		sch->q.qlen++;
 		return NET_XMIT_SUCCESS;
 	}
 	tasklet_schedule(&p->task);
 	return NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
 }

 /*
  * Dequeue packets and send them over ATM. Note that we quite deliberately
  * avoid checking net_device's flow control here, simply because sch_atm
  * uses its own channels, which have nothing to do with any CLIP/LANE/or
  * non-ATM interfaces.
  */

 static void sch_atm_dequeue(unsigned long data)
 {
 	struct Qdisc *sch = (struct Qdisc *)data;
 	struct atm_qdisc_data *p = qdisc_priv(sch);
 	struct atm_flow_data *flow;
 	struct sk_buff *skb;

 	pr_debug("sch_atm_dequeue(sch %p,[qdisc %p])\n", sch, p);
 	list_for_each_entry(flow, &p->flows, list) {
 		if (flow == &p->link)
 			continue;
 		/*
 		 * If traffic is properly shaped, this won't generate nasty
 		 * little bursts. Otherwise, it may ... (but that's okay)
 		 */
 		while ((skb = flow->q->ops->peek(flow->q))) {
 			if (!atm_may_send(flow->vcc, skb->truesize))
 				break;

 			skb = qdisc_dequeue_peeked(flow->q);
 			if (unlikely(!skb))
 				break;

 			pr_debug("atm_tc_dequeue: sending on class %p\n", flow);
 			/* remove any LL header somebody else has attached */
 			skb_pull(skb, skb_network_offset(skb));
 			if (skb_headroom(skb) < flow->hdr_len) {
 				struct sk_buff *new;

 				new = skb_realloc_headroom(skb, flow->hdr_len);
 				dev_kfree_skb(skb);
 				if (!new)
 					continue;
 				skb = new;
 			}
 			pr_debug("sch_atm_dequeue: ip %p, data %p\n",
 				 skb_network_header(skb), skb->data);
 			ATM_SKB(skb)->vcc = flow->vcc;
 			memcpy(skb_push(skb, flow->hdr_len), flow->hdr,
 			       flow->hdr_len);
 			atomic_add(skb->truesize,
 				   &sk_atm(flow->vcc)->sk_wmem_alloc);
 			/* atm.atm_options are already set by atm_tc_enqueue */
 			flow->vcc->send(flow->vcc, skb);
 		}
 	}
 }

 static struct sk_buff *atm_tc_dequeue(struct Qdisc *sch)
 {
 	struct atm_qdisc_data *p = qdisc_priv(sch);
 	struct sk_buff *skb;

 	pr_debug("atm_tc_dequeue(sch %p,[qdisc %p])\n", sch, p);
 	tasklet_schedule(&p->task);
 	skb = qdisc_dequeue_peeked(p->link.q);
 	if (skb)
 		sch->q.qlen--;
 	return skb;
 }

 static struct sk_buff *atm_tc_peek(struct Qdisc *sch)
 {
 	struct atm_qdisc_data *p = qdisc_priv(sch);

 	pr_debug("atm_tc_peek(sch %p,[qdisc %p])\n", sch, p);

 	return p->link.q->ops->peek(p->link.q);
 }

 static unsigned int atm_tc_drop(struct Qdisc *sch)
 {
 	struct atm_qdisc_data *p = qdisc_priv(sch);
 	struct atm_flow_data *flow;
 	unsigned int len;

 	pr_debug("atm_tc_drop(sch %p,[qdisc %p])\n", sch, p);
 	list_for_each_entry(flow, &p->flows, list) {
 		if (flow->q->ops->drop && (len = flow->q->ops->drop(flow->q)))
 			return len;
 	}
 	return 0;
 }

 static int atm_tc_init(struct Qdisc *sch, struct nlattr *opt)
 {
 	struct atm_qdisc_data *p = qdisc_priv(sch);

 	pr_debug("atm_tc_init(sch %p,[qdisc %p],opt %p)\n", sch, p, opt);
 	INIT_LIST_HEAD(&p->flows);
 	INIT_LIST_HEAD(&p->link.list);
 	list_add(&p->link.list, &p->flows);
 	p->link.q = qdisc_create_dflt(sch->dev_queue,
 				      &pfifo_qdisc_ops, sch->handle);
 	if (!p->link.q)
 		p->link.q = &noop_qdisc;
 	pr_debug("atm_tc_init: link (%p) qdisc %p\n", &p->link, p->link.q);
 	p->link.filter_list = NULL;
 	p->link.vcc = NULL;
 	p->link.sock = NULL;
 	p->link.classid = sch->handle;
 	p->link.ref = 1;
 	tasklet_init(&p->task, sch_atm_dequeue, (unsigned long)sch);
 	return 0;
 }

 static void atm_tc_reset(struct Qdisc *sch)
 {
 	struct atm_qdisc_data *p = qdisc_priv(sch);
 	struct atm_flow_data *flow;

 	pr_debug("atm_tc_reset(sch %p,[qdisc %p])\n", sch, p);
 	list_for_each_entry(flow, &p->flows, list)
 		qdisc_reset(flow->q);
 	sch->q.qlen = 0;
 }

 static void atm_tc_destroy(struct Qdisc *sch)
 {
 	struct atm_qdisc_data *p = qdisc_priv(sch);
 	struct atm_flow_data *flow, *tmp;

 	pr_debug("atm_tc_destroy(sch %p,[qdisc %p])\n", sch, p);
 	list_for_each_entry(flow, &p->flows, list)
 		tcf_destroy_chain(&flow->filter_list);

 	list_for_each_entry_safe(flow, tmp, &p->flows, list) {
 		if (flow->ref > 1)
 			printk(KERN_ERR "atm_destroy: %p->ref = %d\n", flow,
 			       flow->ref);
 		atm_tc_put(sch, (unsigned long)flow);
 	}
 	tasklet_kill(&p->task);
 }

 static int atm_tc_dump_class(struct Qdisc *sch, unsigned long cl,
 			     struct sk_buff *skb, struct tcmsg *tcm)
 {
 	struct atm_qdisc_data *p = qdisc_priv(sch);
 	struct atm_flow_data *flow = (struct atm_flow_data *)cl;
 	struct nlattr *nest;

 	pr_debug("atm_tc_dump_class(sch %p,[qdisc %p],flow %p,skb %p,tcm %p)\n",
 		sch, p, flow, skb, tcm);
 	if (list_empty(&flow->list))
 		return -EINVAL;
 	tcm->tcm_handle = flow->classid;
 	tcm->tcm_info = flow->q->handle;

 	nest = nla_nest_start(skb, TCA_OPTIONS);
 	if (nest == NULL)
 		goto nla_put_failure;

 	NLA_PUT(skb, TCA_ATM_HDR, flow->hdr_len, flow->hdr);
 	if (flow->vcc) {
 		struct sockaddr_atmpvc pvc;
 		int state;

 		pvc.sap_family = AF_ATMPVC;
 		pvc.sap_addr.itf = flow->vcc->dev ? flow->vcc->dev->number : -1;
 		pvc.sap_addr.vpi = flow->vcc->vpi;
 		pvc.sap_addr.vci = flow->vcc->vci;
 		NLA_PUT(skb, TCA_ATM_ADDR, sizeof(pvc), &pvc);
 		state = ATM_VF2VS(flow->vcc->flags);
 		NLA_PUT_U32(skb, TCA_ATM_STATE, state);
 	}
 	if (flow->excess)
 		NLA_PUT_U32(skb, TCA_ATM_EXCESS, flow->classid);
 	else {
 		NLA_PUT_U32(skb, TCA_ATM_EXCESS, 0);
 	}

 	nla_nest_end(skb, nest);
 	return skb->len;

 nla_put_failure:
 	nla_nest_cancel(skb, nest);
 	return -1;
 }
 static int
 atm_tc_dump_class_stats(struct Qdisc *sch, unsigned long arg,
 			struct gnet_dump *d)
 {
 	struct atm_flow_data *flow = (struct atm_flow_data *)arg;

 	flow->qstats.qlen = flow->q->q.qlen;

 	if (gnet_stats_copy_basic(d, &flow->bstats) < 0 ||
 	    gnet_stats_copy_queue(d, &flow->qstats) < 0)
 		return -1;

 	return 0;
 }

 static int atm_tc_dump(struct Qdisc *sch, struct sk_buff *skb)
 {
 	return 0;
 }

 static const struct Qdisc_class_ops atm_class_ops = {
 	.graft		= atm_tc_graft,
 	.leaf		= atm_tc_leaf,
 	.get		= atm_tc_get,
 	.put		= atm_tc_put,
 	.change		= atm_tc_change,
 	.delete		= atm_tc_delete,
 	.walk		= atm_tc_walk,
 	.tcf_chain	= atm_tc_find_tcf,
 	.bind_tcf	= atm_tc_bind_filter,
 	.unbind_tcf	= atm_tc_put,
 	.dump		= atm_tc_dump_class,
 	.dump_stats	= atm_tc_dump_class_stats,
 };

 static struct Qdisc_ops atm_qdisc_ops __read_mostly = {
 	.cl_ops		= &atm_class_ops,
 	.id		= "atm",
 	.priv_size	= sizeof(struct atm_qdisc_data),
 	.enqueue	= atm_tc_enqueue,
 	.dequeue	= atm_tc_dequeue,
 	.peek		= atm_tc_peek,
 	.drop		= atm_tc_drop,
 	.init		= atm_tc_init,
 	.reset		= atm_tc_reset,
 	.destroy	= atm_tc_destroy,
 	.dump		= atm_tc_dump,
 	.owner		= THIS_MODULE,
 };

 static int __init atm_init(void)
 {
 	return register_qdisc(&atm_qdisc_ops);
 }

 static void __exit atm_exit(void)
 {
 	unregister_qdisc(&atm_qdisc_ops);
 }

 module_init(atm_init)
 module_exit(atm_exit)
 MODULE_LICENSE("GPL");
	/* net/sched/sch_atm.c - ATM VC selection "queueing discipline" */

	/* Written 1998-2000 by Werner Almesberger, EPFL ICA */

	#include <linux/module.h>
	#include <linux/slab.h>
	#include <linux/init.h>
	#include <linux/string.h>
	#include <linux/errno.h>
	#include <linux/skbuff.h>
	#include <linux/atmdev.h>
	#include <linux/atmclip.h>
	#include <linux/rtnetlink.h>
	#include <linux/file.h> /* for fput */
	#include <net/netlink.h>
	#include <net/pkt_sched.h>

	extern struct socket sockfd_lookup(int fd, int err); /* @@@ fix this */

	/*
	* The ATM queuing discipline provides a framework for invoking classifiers
	* (aka "filters"), which in turn select classes of this queuing discipline.
	* Each class maps the flow(s) it is handling to a given VC. Multiple classes
	* may share the same VC.
	*
	* When creating a class, VCs are specified by passing the number of the open
	* socket descriptor by which the calling process references the VC. The kernel
	* keeps the VC open at least until all classes using it are removed.
	*
	* In this file, most functions are named atm_tc_* to avoid confusion with all
	* the atm_* in net/atm. This naming convention differs from what's used in the
	* rest of net/sched.
	*
	* Known bugs:
	* - sometimes messes up the IP stack
	* - any manipulations besides the few operations described in the README, are
	* untested and likely to crash the system
	* - should lock the flow while there is data in the queue (?)
	*/

	#define VCC2FLOW(vcc) ((struct atm_flow_data *) ((vcc)->user_back))

	struct atm_flow_data {
	struct Qdisc q; / FIFO, TBF, etc. */
	struct tcf_proto *filter_list;
	struct atm_vcc vcc; / VCC; NULL if VCC is closed */
	void (old_pop)(struct atm_vcc vcc,
	struct sk_buff skb); / chaining */
	struct atm_qdisc_data parent; / parent qdisc */
	struct socket sock; / for closing */
	u32 classid; /* x:y type ID */
	int ref; /* reference count */
	struct gnet_stats_basic_packed bstats;
	struct gnet_stats_queue qstats;
	struct list_head list;
	struct atm_flow_data excess; / flow for excess traffic;
	NULL to set CLP instead */
	int hdr_len;
	unsigned char hdr[0]; /* header data; MUST BE LAST */
	};

	struct atm_qdisc_data {
	struct atm_flow_data link; /* unclassified skbs go here */
	struct list_head flows; /* NB: "link" is also on this
	list */
	struct tasklet_struct task; /* dequeue tasklet */
	};

	/* ------------------------- Class/flow operations ------------------------- */

	static inline struct atm_flow_data lookup_flow(struct Qdisc sch, u32 classid)
	{
	struct atm_qdisc_data *p = qdisc_priv(sch);
	struct atm_flow_data *flow;

	list_for_each_entry(flow, &p->flows, list) {
	if (flow->classid == classid)
	return flow;
	}
	return NULL;
	}

	static int atm_tc_graft(struct Qdisc *sch, unsigned long arg,
	struct Qdisc new, struct Qdisc *old)
	{
	struct atm_qdisc_data *p = qdisc_priv(sch);
	struct atm_flow_data flow = (struct atm_flow_data )arg;

	pr_debug("atm_tc_graft(sch %p,[qdisc %p],flow %p,new %p,old %p)\n",
	sch, p, flow, new, old);
	if (list_empty(&flow->list))
	return -EINVAL;
	if (!new)
	new = &noop_qdisc;
	*old = flow->q;
	flow->q = new;
	if (*old)
	qdisc_reset(*old);
	return 0;
	}

	static struct Qdisc atm_tc_leaf(struct Qdisc sch, unsigned long cl)
	{
	struct atm_flow_data flow = (struct atm_flow_data )cl;

	pr_debug("atm_tc_leaf(sch %p,flow %p)\n", sch, flow);
	return flow ? flow->q : NULL;
	}

	static unsigned long atm_tc_get(struct Qdisc *sch, u32 classid)
	{
	struct atm_qdisc_data *p __maybe_unused = qdisc_priv(sch);
	struct atm_flow_data *flow;

	pr_debug("atm_tc_get(sch %p,[qdisc %p],classid %x)\n", sch, p, classid);
	flow = lookup_flow(sch, classid);
	if (flow)
	flow->ref++;
	pr_debug("atm_tc_get: flow %p\n", flow);
	return (unsigned long)flow;
	}

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

	/*
	* atm_tc_put handles all destructions, including the ones that are explicitly
	* requested (atm_tc_destroy, etc.). The assumption here is that we never drop
	* anything that still seems to be in use.
	*/
	static void atm_tc_put(struct Qdisc *sch, unsigned long cl)
	{
	struct atm_qdisc_data *p = qdisc_priv(sch);
	struct atm_flow_data flow = (struct atm_flow_data )cl;

	pr_debug("atm_tc_put(sch %p,[qdisc %p],flow %p)\n", sch, p, flow);
	if (--flow->ref)
	return;
	pr_debug("atm_tc_put: destroying\n");
	list_del_init(&flow->list);
	pr_debug("atm_tc_put: qdisc %p\n", flow->q);
	qdisc_destroy(flow->q);
	tcf_destroy_chain(&flow->filter_list);
	if (flow->sock) {
	pr_debug("atm_tc_put: f_count %ld\n",
	file_count(flow->sock->file));
	flow->vcc->pop = flow->old_pop;
	sockfd_put(flow->sock);
	}
	if (flow->excess)
	atm_tc_put(sch, (unsigned long)flow->excess);
	if (flow != &p->link)
	kfree(flow);
	/*
	* If flow == &p->link, the qdisc no longer works at this point and
	* needs to be removed. (By the caller of atm_tc_put.)
	*/
	}

	static void sch_atm_pop(struct atm_vcc vcc, struct sk_buff skb)
	{
	struct atm_qdisc_data *p = VCC2FLOW(vcc)->parent;

	pr_debug("sch_atm_pop(vcc %p,skb %p,[qdisc %p])\n", vcc, skb, p);
	VCC2FLOW(vcc)->old_pop(vcc, skb);
	tasklet_schedule(&p->task);
	}

	static const u8 llc_oui_ip[] = {
	0xaa, /* DSAP: non-ISO */
	0xaa, /* SSAP: non-ISO */
	0x03, /* Ctrl: Unnumbered Information Command PDU */
	0x00, /* OUI: EtherType */
	0x00, 0x00,
	0x08, 0x00
	}; /* Ethertype IP (0800) */

	static const struct nla_policy atm_policy[TCA_ATM_MAX + 1] = {
	[TCA_ATM_FD] = { .type = NLA_U32 },
	[TCA_ATM_EXCESS] = { .type = NLA_U32 },
	};

	static int atm_tc_change(struct Qdisc *sch, u32 classid, u32 parent,
	struct nlattr *tca, unsigned long arg)
	{
	struct atm_qdisc_data *p = qdisc_priv(sch);
	struct atm_flow_data flow = (struct atm_flow_data )*arg;
	struct atm_flow_data *excess = NULL;
	struct nlattr *opt = tca[TCA_OPTIONS];
	struct nlattr *tb[TCA_ATM_MAX + 1];
	struct socket *sock;
	int fd, error, hdr_len;
	void *hdr;

	pr_debug("atm_tc_change(sch %p,[qdisc %p],classid %x,parent %x,"
	"flow %p,opt %p)\n", sch, p, classid, parent, flow, opt);
	/*
	* The concept of parents doesn't apply for this qdisc.
	*/
	if (parent && parent != TC_H_ROOT && parent != sch->handle)
	return -EINVAL;
	/*
	* ATM classes cannot be changed. In order to change properties of the
	* ATM connection, that socket needs to be modified directly (via the
	* native ATM API. In order to send a flow to a different VC, the old
	* class needs to be removed and a new one added. (This may be changed
	* later.)
	*/
	if (flow)
	return -EBUSY;
	if (opt == NULL)
	return -EINVAL;

	error = nla_parse_nested(tb, TCA_ATM_MAX, opt, atm_policy);
	if (error < 0)
	return error;

	if (!tb[TCA_ATM_FD])
	return -EINVAL;
	fd = nla_get_u32(tb[TCA_ATM_FD]);
	pr_debug("atm_tc_change: fd %d\n", fd);
	if (tb[TCA_ATM_HDR]) {
	hdr_len = nla_len(tb[TCA_ATM_HDR]);
	hdr = nla_data(tb[TCA_ATM_HDR]);
	} else {
	hdr_len = RFC1483LLC_LEN;
	hdr = NULL; /* default LLC/SNAP for IP */
	}
	if (!tb[TCA_ATM_EXCESS])
	excess = NULL;
	else {
	excess = (struct atm_flow_data *)
	atm_tc_get(sch, nla_get_u32(tb[TCA_ATM_EXCESS]));
	if (!excess)
	return -ENOENT;
	}
	pr_debug("atm_tc_change: type %d, payload %d, hdr_len %d\n",
	opt->nla_type, nla_len(opt), hdr_len);
	sock = sockfd_lookup(fd, &error);
	if (!sock)
	return error; /* f_count++ */
	pr_debug("atm_tc_change: f_count %ld\n", file_count(sock->file));
	if (sock->ops->family != PF_ATMSVC && sock->ops->family != PF_ATMPVC) {
	error = -EPROTOTYPE;
	goto err_out;
	}
	/* @@@ should check if the socket is really operational or we'll crash
	on vcc->send */
	if (classid) {
	if (TC_H_MAJ(classid ^ sch->handle)) {
	pr_debug("atm_tc_change: classid mismatch\n");
	error = -EINVAL;
	goto err_out;
	}
	} else {
	int i;
	unsigned long cl;

	for (i = 1; i < 0x8000; i++) {
	classid = TC_H_MAKE(sch->handle, 0x8000 \| i);
	cl = atm_tc_get(sch, classid);
	if (!cl)
	break;
	atm_tc_put(sch, cl);
	}
	}
	pr_debug("atm_tc_change: new id %x\n", classid);
	flow = kzalloc(sizeof(struct atm_flow_data) + hdr_len, GFP_KERNEL);
	pr_debug("atm_tc_change: flow %p\n", flow);
	if (!flow) {
	error = -ENOBUFS;
	goto err_out;
	}
	flow->filter_list = NULL;
	flow->q = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops, classid);
	if (!flow->q)
	flow->q = &noop_qdisc;
	pr_debug("atm_tc_change: qdisc %p\n", flow->q);
	flow->sock = sock;
	flow->vcc = ATM_SD(sock); /* speedup */
	flow->vcc->user_back = flow;
	pr_debug("atm_tc_change: vcc %p\n", flow->vcc);
	flow->old_pop = flow->vcc->pop;
	flow->parent = p;
	flow->vcc->pop = sch_atm_pop;
	flow->classid = classid;
	flow->ref = 1;
	flow->excess = excess;
	list_add(&flow->list, &p->link.list);
	flow->hdr_len = hdr_len;
	if (hdr)
	memcpy(flow->hdr, hdr, hdr_len);
	else
	memcpy(flow->hdr, llc_oui_ip, sizeof(llc_oui_ip));
	*arg = (unsigned long)flow;
	return 0;
	err_out:
	if (excess)
	atm_tc_put(sch, (unsigned long)excess);
	sockfd_put(sock);
	return error;
	}

	static int atm_tc_delete(struct Qdisc *sch, unsigned long arg)
	{
	struct atm_qdisc_data *p = qdisc_priv(sch);
	struct atm_flow_data flow = (struct atm_flow_data )arg;

	pr_debug("atm_tc_delete(sch %p,[qdisc %p],flow %p)\n", sch, p, flow);
	if (list_empty(&flow->list))
	return -EINVAL;
	if (flow->filter_list \|\| flow == &p->link)
	return -EBUSY;
	/*
	* Reference count must be 2: one for "keepalive" (set at class
	* creation), and one for the reference held when calling delete.
	*/
	if (flow->ref < 2) {
	printk(KERN_ERR "atm_tc_delete: flow->ref == %d\n", flow->ref);
	return -EINVAL;
	}
	if (flow->ref > 2)
	return -EBUSY; /* catch references via excess, etc. */
	atm_tc_put(sch, arg);
	return 0;
	}

	static void atm_tc_walk(struct Qdisc sch, struct qdisc_walker walker)
	{
	struct atm_qdisc_data *p = qdisc_priv(sch);
	struct atm_flow_data *flow;

	pr_debug("atm_tc_walk(sch %p,[qdisc %p],walker %p)\n", sch, p, walker);
	if (walker->stop)
	return;
	list_for_each_entry(flow, &p->flows, list) {
	if (walker->count >= walker->skip &&
	walker->fn(sch, (unsigned long)flow, walker) < 0) {
	walker->stop = 1;
	break;
	}
	walker->count++;
	}
	}

	static struct tcf_proto *atm_tc_find_tcf(struct Qdisc sch, unsigned long cl)
	{
	struct atm_qdisc_data *p = qdisc_priv(sch);
	struct atm_flow_data flow = (struct atm_flow_data )cl;

	pr_debug("atm_tc_find_tcf(sch %p,[qdisc %p],flow %p)\n", sch, p, flow);
	return flow ? &flow->filter_list : &p->link.filter_list;
	}

	/* --------------------------- Qdisc operations ---------------------------- */

	static int atm_tc_enqueue(struct sk_buff skb, struct Qdisc sch)
	{
	struct atm_qdisc_data *p = qdisc_priv(sch);
	struct atm_flow_data *flow;
	struct tcf_result res;
	int result;
	int ret = NET_XMIT_POLICED;

	pr_debug("atm_tc_enqueue(skb %p,sch %p,[qdisc %p])\n", skb, sch, p);
	result = TC_POLICE_OK; /* be nice to gcc */
	flow = NULL;
	if (TC_H_MAJ(skb->priority) != sch->handle \|\|
	!(flow = (struct atm_flow_data *)atm_tc_get(sch, skb->priority))) {
	list_for_each_entry(flow, &p->flows, list) {
	if (flow->filter_list) {
	result = tc_classify_compat(skb,
	flow->filter_list,
	&res);
	if (result < 0)
	continue;
	flow = (struct atm_flow_data *)res.class;
	if (!flow)
	flow = lookup_flow(sch, res.classid);
	goto done;
	}
	}
	flow = NULL;
	done:
	;
	}
	if (!flow)
	flow = &p->link;
	else {
	if (flow->vcc)
	ATM_SKB(skb)->atm_options = flow->vcc->atm_options;
	/@@@ looks good ... but it's not supposed to work :-) /
	#ifdef CONFIG_NET_CLS_ACT
	switch (result) {
	case TC_ACT_QUEUED:
	case TC_ACT_STOLEN:
	kfree_skb(skb);
	return NET_XMIT_SUCCESS \| __NET_XMIT_STOLEN;
	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;
	}
	#endif
	}

	ret = qdisc_enqueue(skb, flow->q);
	if (ret != NET_XMIT_SUCCESS) {
	drop: __maybe_unused
	if (net_xmit_drop_count(ret)) {
	sch->qstats.drops++;
	if (flow)
	flow->qstats.drops++;
	}
	return ret;
	}
	sch->bstats.bytes += qdisc_pkt_len(skb);
	sch->bstats.packets++;
	flow->bstats.bytes += qdisc_pkt_len(skb);
	flow->bstats.packets++;
	/*
	* Okay, this may seem weird. We pretend we've dropped the packet if
	* it goes via ATM. The reason for this is that the outer qdisc
	* expects to be able to q->dequeue the packet later on if we return
	* success at this place. Also, sch->q.qdisc needs to reflect whether
	* there is a packet egligible for dequeuing or not. Note that the
	* statistics of the outer qdisc are necessarily wrong because of all
	* this. There's currently no correct solution for this.
	*/
	if (flow == &p->link) {
	sch->q.qlen++;
	return NET_XMIT_SUCCESS;
	}
	tasklet_schedule(&p->task);
	return NET_XMIT_SUCCESS \| __NET_XMIT_BYPASS;
	}

	/*
	* Dequeue packets and send them over ATM. Note that we quite deliberately
	* avoid checking net_device's flow control here, simply because sch_atm
	* uses its own channels, which have nothing to do with any CLIP/LANE/or
	* non-ATM interfaces.
	*/

	static void sch_atm_dequeue(unsigned long data)
	{
	struct Qdisc sch = (struct Qdisc )data;
	struct atm_qdisc_data *p = qdisc_priv(sch);
	struct atm_flow_data *flow;
	struct sk_buff *skb;

	pr_debug("sch_atm_dequeue(sch %p,[qdisc %p])\n", sch, p);
	list_for_each_entry(flow, &p->flows, list) {
	if (flow == &p->link)
	continue;
	/*
	* If traffic is properly shaped, this won't generate nasty
	* little bursts. Otherwise, it may ... (but that's okay)
	*/
	while ((skb = flow->q->ops->peek(flow->q))) {
	if (!atm_may_send(flow->vcc, skb->truesize))
	break;

	skb = qdisc_dequeue_peeked(flow->q);
	if (unlikely(!skb))
	break;

	pr_debug("atm_tc_dequeue: sending on class %p\n", flow);
	/* remove any LL header somebody else has attached */
	skb_pull(skb, skb_network_offset(skb));
	if (skb_headroom(skb) < flow->hdr_len) {
	struct sk_buff *new;

	new = skb_realloc_headroom(skb, flow->hdr_len);
	dev_kfree_skb(skb);
	if (!new)
	continue;
	skb = new;
	}
	pr_debug("sch_atm_dequeue: ip %p, data %p\n",
	skb_network_header(skb), skb->data);
	ATM_SKB(skb)->vcc = flow->vcc;
	memcpy(skb_push(skb, flow->hdr_len), flow->hdr,
	flow->hdr_len);
	atomic_add(skb->truesize,
	&sk_atm(flow->vcc)->sk_wmem_alloc);
	/* atm.atm_options are already set by atm_tc_enqueue */
	flow->vcc->send(flow->vcc, skb);
	}
	}
	}

	static struct sk_buff atm_tc_dequeue(struct Qdisc sch)
	{
	struct atm_qdisc_data *p = qdisc_priv(sch);
	struct sk_buff *skb;

	pr_debug("atm_tc_dequeue(sch %p,[qdisc %p])\n", sch, p);
	tasklet_schedule(&p->task);
	skb = qdisc_dequeue_peeked(p->link.q);
	if (skb)
	sch->q.qlen--;
	return skb;
	}

	static struct sk_buff atm_tc_peek(struct Qdisc sch)
	{
	struct atm_qdisc_data *p = qdisc_priv(sch);

	pr_debug("atm_tc_peek(sch %p,[qdisc %p])\n", sch, p);

	return p->link.q->ops->peek(p->link.q);
	}

	static unsigned int atm_tc_drop(struct Qdisc *sch)
	{
	struct atm_qdisc_data *p = qdisc_priv(sch);
	struct atm_flow_data *flow;
	unsigned int len;

	pr_debug("atm_tc_drop(sch %p,[qdisc %p])\n", sch, p);
	list_for_each_entry(flow, &p->flows, list) {
	if (flow->q->ops->drop && (len = flow->q->ops->drop(flow->q)))
	return len;
	}
	return 0;
	}

	static int atm_tc_init(struct Qdisc sch, struct nlattr opt)
	{
	struct atm_qdisc_data *p = qdisc_priv(sch);

	pr_debug("atm_tc_init(sch %p,[qdisc %p],opt %p)\n", sch, p, opt);
	INIT_LIST_HEAD(&p->flows);
	INIT_LIST_HEAD(&p->link.list);
	list_add(&p->link.list, &p->flows);
	p->link.q = qdisc_create_dflt(sch->dev_queue,
	&pfifo_qdisc_ops, sch->handle);
	if (!p->link.q)
	p->link.q = &noop_qdisc;
	pr_debug("atm_tc_init: link (%p) qdisc %p\n", &p->link, p->link.q);
	p->link.filter_list = NULL;
	p->link.vcc = NULL;
	p->link.sock = NULL;
	p->link.classid = sch->handle;
	p->link.ref = 1;
	tasklet_init(&p->task, sch_atm_dequeue, (unsigned long)sch);
	return 0;
	}

	static void atm_tc_reset(struct Qdisc *sch)
	{
	struct atm_qdisc_data *p = qdisc_priv(sch);
	struct atm_flow_data *flow;

	pr_debug("atm_tc_reset(sch %p,[qdisc %p])\n", sch, p);
	list_for_each_entry(flow, &p->flows, list)
	qdisc_reset(flow->q);
	sch->q.qlen = 0;
	}

	static void atm_tc_destroy(struct Qdisc *sch)
	{
	struct atm_qdisc_data *p = qdisc_priv(sch);
	struct atm_flow_data flow, tmp;

	pr_debug("atm_tc_destroy(sch %p,[qdisc %p])\n", sch, p);
	list_for_each_entry(flow, &p->flows, list)
	tcf_destroy_chain(&flow->filter_list);

	list_for_each_entry_safe(flow, tmp, &p->flows, list) {
	if (flow->ref > 1)
	printk(KERN_ERR "atm_destroy: %p->ref = %d\n", flow,
	flow->ref);
	atm_tc_put(sch, (unsigned long)flow);
	}
	tasklet_kill(&p->task);
	}

	static int atm_tc_dump_class(struct Qdisc *sch, unsigned long cl,
	struct sk_buff skb, struct tcmsg tcm)
	{
	struct atm_qdisc_data *p = qdisc_priv(sch);
	struct atm_flow_data flow = (struct atm_flow_data )cl;
	struct nlattr *nest;

	pr_debug("atm_tc_dump_class(sch %p,[qdisc %p],flow %p,skb %p,tcm %p)\n",
	sch, p, flow, skb, tcm);
	if (list_empty(&flow->list))
	return -EINVAL;
	tcm->tcm_handle = flow->classid;
	tcm->tcm_info = flow->q->handle;

	nest = nla_nest_start(skb, TCA_OPTIONS);
	if (nest == NULL)
	goto nla_put_failure;

	NLA_PUT(skb, TCA_ATM_HDR, flow->hdr_len, flow->hdr);
	if (flow->vcc) {
	struct sockaddr_atmpvc pvc;
	int state;

	pvc.sap_family = AF_ATMPVC;
	pvc.sap_addr.itf = flow->vcc->dev ? flow->vcc->dev->number : -1;
	pvc.sap_addr.vpi = flow->vcc->vpi;
	pvc.sap_addr.vci = flow->vcc->vci;
	NLA_PUT(skb, TCA_ATM_ADDR, sizeof(pvc), &pvc);
	state = ATM_VF2VS(flow->vcc->flags);
	NLA_PUT_U32(skb, TCA_ATM_STATE, state);
	}
	if (flow->excess)
	NLA_PUT_U32(skb, TCA_ATM_EXCESS, flow->classid);
	else {
	NLA_PUT_U32(skb, TCA_ATM_EXCESS, 0);
	}

	nla_nest_end(skb, nest);
	return skb->len;

	nla_put_failure:
	nla_nest_cancel(skb, nest);
	return -1;
	}
	static int
	atm_tc_dump_class_stats(struct Qdisc *sch, unsigned long arg,
	struct gnet_dump *d)
	{
	struct atm_flow_data flow = (struct atm_flow_data )arg;

	flow->qstats.qlen = flow->q->q.qlen;

	if (gnet_stats_copy_basic(d, &flow->bstats) < 0 \|\|
	gnet_stats_copy_queue(d, &flow->qstats) < 0)
	return -1;

	return 0;
	}

	static int atm_tc_dump(struct Qdisc sch, struct sk_buff skb)
	{
	return 0;
	}

	static const struct Qdisc_class_ops atm_class_ops = {
	.graft = atm_tc_graft,
	.leaf = atm_tc_leaf,
	.get = atm_tc_get,
	.put = atm_tc_put,
	.change = atm_tc_change,
	.delete = atm_tc_delete,
	.walk = atm_tc_walk,
	.tcf_chain = atm_tc_find_tcf,
	.bind_tcf = atm_tc_bind_filter,
	.unbind_tcf = atm_tc_put,
	.dump = atm_tc_dump_class,
	.dump_stats = atm_tc_dump_class_stats,
	};

	static struct Qdisc_ops atm_qdisc_ops __read_mostly = {
	.cl_ops = &atm_class_ops,
	.id = "atm",
	.priv_size = sizeof(struct atm_qdisc_data),
	.enqueue = atm_tc_enqueue,
	.dequeue = atm_tc_dequeue,
	.peek = atm_tc_peek,
	.drop = atm_tc_drop,
	.init = atm_tc_init,
	.reset = atm_tc_reset,
	.destroy = atm_tc_destroy,
	.dump = atm_tc_dump,
	.owner = THIS_MODULE,
	};

	static int __init atm_init(void)
	{
	return register_qdisc(&atm_qdisc_ops);
	}

	static void __exit atm_exit(void)
	{
	unregister_qdisc(&atm_qdisc_ops);
	}

	module_init(atm_init)
	module_exit(atm_exit)
	MODULE_LICENSE("GPL");