text: /* net/sched/sch_atm.c - ATM VC selection "queueing discipline" */
  
  /* Written 1998-2000 by Werner Almesberger, EPFL ICA */
  
  
  #include <linux/module.h>
  #include <linux/init.h>
  #include <linux/string.h>
  #include <linux/errno.h>
  #include <linux/skbuff.h>
  #include <linux/interrupt.h>
  #include <linux/atmdev.h>
  #include <linux/atmclip.h>
  #include <linux/netdevice.h>
  #include <linux/rtnetlink.h>
  #include <linux/file.h> /* for fput */
  #include <net/netlink.h>
  #include <net/pkt_sched.h>
  #include <net/sock.h>
  
  
  extern struct socket *sockfd_lookup(int fd, int *err); /* @@@ fix this */
  
  #if 0 /* control */
  #define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
  #else
  #define DPRINTK(format,args...)
  #endif
  
  #if 0 /* data */
  #define D2PRINTK(format,args...) printk(KERN_DEBUG format,##args)
  #else
  #define D2PRINTK(format,args...)
  #endif
  
  
  /*
   * 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 PRIV(sch) qdisc_priv(sch)
  #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	bstats;
  	struct gnet_stats_queue	qstats;
  	spinlock_t		*stats_lock;
  	struct atm_flow_data	*next;
  	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 atm_flow_data	*flows;		/* NB: "link" is also on this
  						   list */
  	struct tasklet_struct	task;		/* requeue tasklet */
  };
  
  
  /* ------------------------- Class/flow operations ------------------------- */
  
  
  static int find_flow(struct atm_qdisc_data *qdisc,struct atm_flow_data *flow)
  {
  	struct atm_flow_data *walk;
  
  	DPRINTK("find_flow(qdisc %p,flow %p)\n",qdisc,flow);
  	for (walk = qdisc->flows; walk; walk = walk->next)
  		if (walk == flow) return 1;
  	DPRINTK("find_flow: not found\n");
  	return 0;
  }
  
  
  static __inline__ struct atm_flow_data *lookup_flow(struct Qdisc *sch,
      u32 classid)
  {
  	struct atm_qdisc_data *p = PRIV(sch);
  	struct atm_flow_data *flow;
  
  	for (flow = p->flows; flow; flow = flow->next)
  		if (flow->classid == classid) break;
  	return flow;
  }
  
  
  static int atm_tc_graft(struct Qdisc *sch,unsigned long arg,
      struct Qdisc *new,struct Qdisc **old)
  {
  	struct atm_qdisc_data *p = PRIV(sch);
  	struct atm_flow_data *flow = (struct atm_flow_data *) arg;
  
  	DPRINTK("atm_tc_graft(sch %p,[qdisc %p],flow %p,new %p,old %p)\n",sch,
  	    p,flow,new,old);
  	if (!find_flow(p,flow)) return -EINVAL;
  	if (!new) new = &noop_qdisc;
  	*old = xchg(&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;
  
  	DPRINTK("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 __attribute__((unused)) = PRIV(sch);
  	struct atm_flow_data *flow;
  
  	DPRINTK("atm_tc_get(sch %p,[qdisc %p],classid %x)\n",sch,p,classid);
  	flow = lookup_flow(sch,classid);
  	if (flow) flow->ref++;
  	DPRINTK("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 = PRIV(sch);
  	struct atm_flow_data *flow = (struct atm_flow_data *) cl;
  	struct atm_flow_data **prev;
  
  	DPRINTK("atm_tc_put(sch %p,[qdisc %p],flow %p)\n",sch,p,flow);
  	if (--flow->ref) return;
  	DPRINTK("atm_tc_put: destroying\n");
  	for (prev = &p->flows; *prev; prev = &(*prev)->next)
  		if (*prev == flow) break;
  	if (!*prev) {
  		printk(KERN_CRIT "atm_tc_put: class %p not found\n",flow);
  		return;
  	}
  	*prev = flow->next;
  	DPRINTK("atm_tc_put: qdisc %p\n",flow->q);
  	qdisc_destroy(flow->q);
  	tcf_destroy_chain(flow->filter_list);
  	if (flow->sock) {
  		DPRINTK("atm_tc_put: f_count %d\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;
  
  	D2PRINTK("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 int atm_tc_change(struct Qdisc *sch, u32 classid, u32 parent,
      struct rtattr **tca, unsigned long *arg)
  {
  	struct atm_qdisc_data *p = PRIV(sch);
  	struct atm_flow_data *flow = (struct atm_flow_data *) *arg;
  	struct atm_flow_data *excess = NULL;
  	struct rtattr *opt = tca[TCA_OPTIONS-1];
  	struct rtattr *tb[TCA_ATM_MAX];
  	struct socket *sock;
  	int fd,error,hdr_len;
  	void *hdr;
  
  	DPRINTK("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 || rtattr_parse_nested(tb, TCA_ATM_MAX, opt))
  		return -EINVAL;
  	if (!tb[TCA_ATM_FD-1] || RTA_PAYLOAD(tb[TCA_ATM_FD-1]) < sizeof(fd))
  		return -EINVAL;
  	fd = *(int *) RTA_DATA(tb[TCA_ATM_FD-1]);
  	DPRINTK("atm_tc_change: fd %d\n",fd);
  	if (tb[TCA_ATM_HDR-1]) {
  		hdr_len = RTA_PAYLOAD(tb[TCA_ATM_HDR-1]);
  		hdr = RTA_DATA(tb[TCA_ATM_HDR-1]);
  	}
  	else {
  		hdr_len = RFC1483LLC_LEN;
  		hdr = NULL; /* default LLC/SNAP for IP */
  	}
  	if (!tb[TCA_ATM_EXCESS-1]) excess = NULL;
  	else {
  		if (RTA_PAYLOAD(tb[TCA_ATM_EXCESS-1]) != sizeof(u32))
  			return -EINVAL;
  		excess = (struct atm_flow_data *) atm_tc_get(sch,
  		    *(u32 *) RTA_DATA(tb[TCA_ATM_EXCESS-1]));
  		if (!excess) return -ENOENT;
  	}
  	DPRINTK("atm_tc_change: type %d, payload %d, hdr_len %d\n",
  	    opt->rta_type,RTA_PAYLOAD(opt),hdr_len);
  	if (!(sock = sockfd_lookup(fd,&error))) return error; /* f_count++ */
  	DPRINTK("atm_tc_change: f_count %d\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)) {
  			DPRINTK("atm_tc_change: classid mismatch\n");
  			error = -EINVAL;
  			goto err_out;
  		}
  		if (find_flow(p,flow)) {
  			error = -EEXIST;
  			goto err_out;
  		}
  	}
  	else {
  		int i;
  		unsigned long cl;
  
  		for (i = 1; i < 0x8000; i++) {
  			classid = TC_H_MAKE(sch->handle,0x8000 | i);
  			if (!(cl = atm_tc_get(sch,classid))) break;
  			atm_tc_put(sch,cl);
  		}
  	}
  	DPRINTK("atm_tc_change: new id %x\n",classid);
  	flow = kmalloc(sizeof(struct atm_flow_data)+hdr_len,GFP_KERNEL);
  	DPRINTK("atm_tc_change: flow %p\n",flow);
  	if (!flow) {
  		error = -ENOBUFS;
  		goto err_out;
  	}
  	memset(flow,0,sizeof(*flow));
  	flow->filter_list = NULL;
  	if (!(flow->q = qdisc_create_dflt(sch->dev,&pfifo_qdisc_ops,classid)))
  		flow->q = &noop_qdisc;
  	DPRINTK("atm_tc_change: qdisc %p\n",flow->q);
  	flow->sock = sock;
  	flow->vcc = ATM_SD(sock); /* speedup */
  	flow->vcc->user_back = flow;
  	DPRINTK("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;
  	flow->next = p->link.next;
  	p->link.next = flow;
  	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 = PRIV(sch);
  	struct atm_flow_data *flow = (struct atm_flow_data *) arg;
  
  	DPRINTK("atm_tc_delete(sch %p,[qdisc %p],flow %p)\n",sch,p,flow);
  	if (!find_flow(PRIV(sch),flow)) 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 = PRIV(sch);
  	struct atm_flow_data *flow;
  
  	DPRINTK("atm_tc_walk(sch %p,[qdisc %p],walker %p)\n",sch,p,walker);
  	if (walker->stop) return;
  	for (flow = p->flows; flow; flow = flow->next) {
  		if (walker->count >= walker->skip)
  			if (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 = PRIV(sch);
  	struct atm_flow_data *flow = (struct atm_flow_data *) cl;
  
  	DPRINTK("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 = PRIV(sch);
  	struct atm_flow_data *flow = NULL ; /* @@@ */
  	struct tcf_result res;
  	int result;
  	int ret = NET_XMIT_POLICED;
  
  	D2PRINTK("atm_tc_enqueue(skb %p,sch %p,[qdisc %p])\n",skb,sch,p);
  	result = TC_POLICE_OK; /* be nice to gcc */
  	if (TC_H_MAJ(skb->priority) != sch->handle ||
  	    !(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,
  				    &res);
  				if (result < 0) continue;
  				flow = (struct atm_flow_data *) res.class;
  				if (!flow) flow = lookup_flow(sch,res.classid);
  				break;
  			}
  	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_POLICE
  		switch (result) {
  			case TC_POLICE_SHOT:
  				kfree_skb(skb);
  				break;
  			case TC_POLICE_RECLASSIFY:
  				if (flow->excess) flow = flow->excess;
  				else {
  					ATM_SKB(skb)->atm_options |=
  					    ATM_ATMOPT_CLP;
  					break;
  				}
  				/* fall through */
  			case TC_POLICE_OK:
  				/* fall through */
  			default:
  				break;
  		}
  #endif
  	}
  	if (
  #ifdef CONFIG_NET_CLS_POLICE
  	    result == TC_POLICE_SHOT ||
  #endif
  	    (ret = flow->q->enqueue(skb,flow->q)) != 0) {
  		sch->qstats.drops++;
  		if (flow) flow->qstats.drops++;
  		return ret;
  	}
  	sch->bstats.bytes += skb->len;
  	sch->bstats.packets++;
  	flow->bstats.bytes += skb->len;
  	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 0;
  	}
  	tasklet_schedule(&p->task);
  	return 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 = PRIV(sch);
  	struct atm_flow_data *flow;
  	struct sk_buff *skb;
  
  	D2PRINTK("sch_atm_dequeue(sch %p,[qdisc %p])\n",sch,p);
  	for (flow = p->link.next; flow; flow = flow->next)
  		/*
  		 * If traffic is properly shaped, this won't generate nasty
  		 * little bursts. Otherwise, it may ... (but that's okay)
  		 */
  		while ((skb = flow->q->dequeue(flow->q))) {
  			if (!atm_may_send(flow->vcc,skb->truesize)) {
  				(void) flow->q->ops->requeue(skb,flow->q);
  				break;
  			}
  			D2PRINTK("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;
  			}
  			D2PRINTK("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 */
  			(void) flow->vcc->send(flow->vcc,skb);
  		}
  }
  
  
  static struct sk_buff *atm_tc_dequeue(struct Qdisc *sch)
  {
  	struct atm_qdisc_data *p = PRIV(sch);
  	struct sk_buff *skb;
  
  	D2PRINTK("atm_tc_dequeue(sch %p,[qdisc %p])\n",sch,p);
  	tasklet_schedule(&p->task);
  	skb = p->link.q->dequeue(p->link.q);
  	if (skb) sch->q.qlen--;
  	return skb;
  }
  
  
  static int atm_tc_requeue(struct sk_buff *skb,struct Qdisc *sch)
  {
  	struct atm_qdisc_data *p = PRIV(sch);
  	int ret;
  
  	D2PRINTK("atm_tc_requeue(skb %p,sch %p,[qdisc %p])\n",skb,sch,p);
  	ret = p->link.q->ops->requeue(skb,p->link.q);
  	if (!ret) {
  	sch->q.qlen++;
  	sch->qstats.requeues++;
      } else {
  		sch->qstats.drops++;
  		p->link.qstats.drops++;
  	}
  	return ret;
  }
  
  
  static unsigned int atm_tc_drop(struct Qdisc *sch)
  {
  	struct atm_qdisc_data *p = PRIV(sch);
  	struct atm_flow_data *flow;
  	unsigned int len;
  
  	DPRINTK("atm_tc_drop(sch %p,[qdisc %p])\n",sch,p);
  	for (flow = p->flows; flow; flow = flow->next)
  		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 rtattr *opt)
  {
  	struct atm_qdisc_data *p = PRIV(sch);
  
  	DPRINTK("atm_tc_init(sch %p,[qdisc %p],opt %p)\n",sch,p,opt);
  	p->flows = &p->link;
  	if(!(p->link.q = qdisc_create_dflt(sch->dev,&pfifo_qdisc_ops,
  					   sch->handle)))
  		p->link.q = &noop_qdisc;
  	DPRINTK("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;
  	p->link.next = NULL;
  	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 = PRIV(sch);
  	struct atm_flow_data *flow;
  
  	DPRINTK("atm_tc_reset(sch %p,[qdisc %p])\n",sch,p);
  	for (flow = p->flows; flow; flow = flow->next) qdisc_reset(flow->q);
  	sch->q.qlen = 0;
  }
  
  
  static void atm_tc_destroy(struct Qdisc *sch)
  {
  	struct atm_qdisc_data *p = PRIV(sch);
  	struct atm_flow_data *flow;
  
  	DPRINTK("atm_tc_destroy(sch %p,[qdisc %p])\n",sch,p);
  	/* races ? */
  	while ((flow = p->flows)) {
  		tcf_destroy_chain(flow->filter_list);
  		flow->filter_list = NULL;
  		if (flow->ref > 1)
  			printk(KERN_ERR "atm_destroy: %p->ref = %d\n",flow,
  			    flow->ref);
  		atm_tc_put(sch,(unsigned long) flow);
  		if (p->flows == flow) {
  			printk(KERN_ERR "atm_destroy: putting flow %p didn't "
  			    "kill it\n",flow);
  			p->flows = flow->next; /* brute force */
  			break;
  		}
  	}
  	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 = PRIV(sch);
  	struct atm_flow_data *flow = (struct atm_flow_data *) cl;
  	unsigned char *b = skb_tail_pointer(skb);
  	struct rtattr *rta;
  
  	DPRINTK("atm_tc_dump_class(sch %p,[qdisc %p],flow %p,skb %p,tcm %p)\n",
  	    sch,p,flow,skb,tcm);
  	if (!find_flow(p,flow)) return -EINVAL;
  	tcm->tcm_handle = flow->classid;
  	tcm->tcm_info = flow->q->handle;
  	rta = (struct rtattr *) b;
  	RTA_PUT(skb,TCA_OPTIONS,0,NULL);
  	RTA_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;
  		RTA_PUT(skb,TCA_ATM_ADDR,sizeof(pvc),&pvc);
  		state = ATM_VF2VS(flow->vcc->flags);
  		RTA_PUT(skb,TCA_ATM_STATE,sizeof(state),&state);
  	}
  	if (flow->excess)
  		RTA_PUT(skb,TCA_ATM_EXCESS,sizeof(u32),&flow->classid);
  	else {
  		static u32 zero;
  
  		RTA_PUT(skb,TCA_ATM_EXCESS,sizeof(zero),&zero);
  	}
  	rta->rta_len = skb_tail_pointer(skb) - b;
  	return skb->len;
  
  rtattr_failure:
  	nlmsg_trim(skb, b);
  	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 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 = {
  	.next		=	NULL,
  	.cl_ops		=	&atm_class_ops,
  	.id		=	"atm",
  	.priv_size	=	sizeof(struct atm_qdisc_data),
  	.enqueue	=	atm_tc_enqueue,
  	.dequeue	=	atm_tc_dequeue,
  	.requeue	=	atm_tc_requeue,
  	.drop		=	atm_tc_drop,
  	.init		=	atm_tc_init,
  	.reset		=	atm_tc_reset,
  	.destroy	=	atm_tc_destroy,
  	.change		=	NULL,
  	.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");
  