Merge with Linux 2.5.59.

[linux-2.6/linux-mips.git] / net / sched / sch_atm.c

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

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


#include <linux/config.h>
#include <linux/module.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/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) ((struct atm_qdisc_data *) (sch)->data)
#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 tc_stats         stats;
        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_flow_data *flow;

        for (flow = PRIV(sch)->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);
}


static void destroy_filters(struct atm_flow_data *flow)
{
        struct tcf_proto *filter;

        while ((filter = flow->filter_list)) {
                DPRINTK("destroy_filters: destroying filter %p\n",filter);
                flow->filter_list = filter->next;
                filter->ops->destroy(filter);
        }
}


/*
 * 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);
        destroy_filters(flow);
        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 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(tb,TCA_ATM_MAX,RTA_DATA(opt),
            RTA_PAYLOAD(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)))
                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,sizeof(llc_oui));
                ((u16 *) flow->hdr)[3] = htons(ETH_P_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->stats.drops++;
                if (flow) flow->stats.drops++;
                return ret;
        }
        sch->stats.bytes += skb->len;
        sch->stats.packets++;
        flow->stats.bytes += skb->len;
        flow->stats.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_deqeueue: sending on class %p\n",flow);
                        /* remove any LL header somebody else has attached */
                        skb_pull(skb,(char *) skb->nh.iph-(char *) skb->data);
                        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->nh.iph,skb->data);
                        ATM_SKB(skb)->vcc = flow->vcc;
                        memcpy(skb_push(skb,flow->hdr_len),flow->hdr,
                            flow->hdr_len);
                        atomic_add(skb->truesize,&flow->vcc->tx_inuse);
                        ATM_SKB(skb)->iovcnt = 0;
                        /* 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++;
        else {
                sch->stats.drops++;
                p->link.stats.drops++;
        }
        return ret;
}


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

        DPRINTK("atm_tc_drop(sch %p,[qdisc %p])\n",sch,p);
        for (flow = p->flows; flow; flow = flow->next)
                if (flow->q->ops->drop && flow->q->ops->drop(flow->q))
                        return 1;
        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);
        memset(p,0,sizeof(*p));
        p->flows = &p->link;
        if(!(p->link.q = qdisc_create_dflt(sch->dev,&pfifo_qdisc_ops)))
                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);
        MOD_INC_USE_COUNT;
        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)) {
                destroy_filters(flow);
                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);
        MOD_DEC_USE_COUNT;
}


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;
        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;
        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 = 0;

                RTA_PUT(skb,TCA_ATM_EXCESS,sizeof(zero),&zero);
        }
        rta->rta_len = skb->tail-b;
        return skb->len;

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

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,
};

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
};


#ifdef MODULE
int init_module(void)
{
        return register_qdisc(&atm_qdisc_ops);
}


void cleanup_module(void) 
{
        unregister_qdisc(&atm_qdisc_ops);
}
#endif