net/sched/sch_atm.c

   1 /* net/sched/sch_atm.c - ATM VC selection "queueing discipline" */
   2
   3 /* Written 1998-2000 by Werner Almesberger, EPFL ICA */
   4
   5 #include <linux/module.h>
   6 #include <linux/init.h>
   7 #include <linux/string.h>
   8 #include <linux/errno.h>
   9 #include <linux/skbuff.h>
  10 #include <linux/atmdev.h>
  11 #include <linux/atmclip.h>
  12 #include <linux/rtnetlink.h>
  13 #include <linux/file.h>         /* for fput */
  14 #include <net/netlink.h>
  15 #include <net/pkt_sched.h>
  16
  17 extern struct socket *sockfd_lookup(int fd, int *err);  /* @@@ fix this */
  18
  19 #if 0 /* control */
  20 #define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
  21 #else
  22 #define DPRINTK(format,args...)
  23 #endif
  24
  25 #if 0 /* data */
  26 #define D2PRINTK(format,args...) printk(KERN_DEBUG format,##args)
  27 #else
  28 #define D2PRINTK(format,args...)
  29 #endif
  30
  31 /*
  32  * The ATM queuing discipline provides a framework for invoking classifiers
  33  * (aka "filters"), which in turn select classes of this queuing discipline.
  34  * Each class maps the flow(s) it is handling to a given VC. Multiple classes
  35  * may share the same VC.
  36  *
  37  * When creating a class, VCs are specified by passing the number of the open
  38  * socket descriptor by which the calling process references the VC. The kernel
  39  * keeps the VC open at least until all classes using it are removed.
  40  *
  41  * In this file, most functions are named atm_tc_* to avoid confusion with all
  42  * the atm_* in net/atm. This naming convention differs from what's used in the
  43  * rest of net/sched.
  44  *
  45  * Known bugs:
  46  *  - sometimes messes up the IP stack
  47  *  - any manipulations besides the few operations described in the README, are
  48  *    untested and likely to crash the system
  49  *  - should lock the flow while there is data in the queue (?)
  50  */
  51
  52 #define PRIV(sch) qdisc_priv(sch)
  53 #define VCC2FLOW(vcc) ((struct atm_flow_data *) ((vcc)->user_back))
  54
  55 struct atm_flow_data {
  56         struct Qdisc            *q;     /* FIFO, TBF, etc. */
  57         struct tcf_proto        *filter_list;
  58         struct atm_vcc          *vcc;   /* VCC; NULL if VCC is closed */
  59         void                    (*old_pop)(struct atm_vcc *vcc,
  60                                            struct sk_buff * skb); /* chaining */
  61         struct atm_qdisc_data   *parent;        /* parent qdisc */
  62         struct socket           *sock;          /* for closing */
  63         u32                     classid;        /* x:y type ID */
  64         int                     ref;            /* reference count */
  65         struct gnet_stats_basic bstats;
  66         struct gnet_stats_queue qstats;
  67         struct atm_flow_data    *next;
  68         struct atm_flow_data    *excess;        /* flow for excess traffic;
  69                                                    NULL to set CLP instead */
  70         int                     hdr_len;
  71         unsigned char           hdr[0];         /* header data; MUST BE LAST */
  72 };
  73
  74 struct atm_qdisc_data {
  75         struct atm_flow_data    link;           /* unclassified skbs go here */
  76         struct atm_flow_data    *flows;         /* NB: "link" is also on this
  77                                                    list */
  78         struct tasklet_struct   task;           /* requeue tasklet */
  79 };
  80
  81 /* ------------------------- Class/flow operations ------------------------- */
  82
  83 static int find_flow(struct atm_qdisc_data *qdisc, struct atm_flow_data *flow)
  84 {
  85         struct atm_flow_data *walk;
  86
  87         DPRINTK("find_flow(qdisc %p,flow %p)\n", qdisc, flow);
  88         for (walk = qdisc->flows; walk; walk = walk->next)
  89                 if (walk == flow)
  90                         return 1;
  91         DPRINTK("find_flow: not found\n");
  92         return 0;
  93 }
  94
  95 static inline struct atm_flow_data *lookup_flow(struct Qdisc *sch, u32 classid)
  96 {
  97         struct atm_qdisc_data *p = PRIV(sch);
  98         struct atm_flow_data *flow;
  99
 100         for (flow = p->flows; flow; flow = flow->next)
 101                 if (flow->classid == classid)
 102                         break;
 103         return flow;
 104 }
 105
 106 static int atm_tc_graft(struct Qdisc *sch, unsigned long arg,
 107                         struct Qdisc *new, struct Qdisc **old)
 108 {
 109         struct atm_qdisc_data *p = PRIV(sch);
 110         struct atm_flow_data *flow = (struct atm_flow_data *)arg;
 111
 112         DPRINTK("atm_tc_graft(sch %p,[qdisc %p],flow %p,new %p,old %p)\n",
 113                 sch, p, flow, new, old);
 114         if (!find_flow(p, flow))
 115                 return -EINVAL;
 116         if (!new)
 117                 new = &noop_qdisc;
 118         *old = xchg(&flow->q, new);
 119         if (*old)
 120                 qdisc_reset(*old);
 121         return 0;
 122 }
 123
 124 static struct Qdisc *atm_tc_leaf(struct Qdisc *sch, unsigned long cl)
 125 {
 126         struct atm_flow_data *flow = (struct atm_flow_data *)cl;
 127
 128         DPRINTK("atm_tc_leaf(sch %p,flow %p)\n", sch, flow);
 129         return flow ? flow->q : NULL;
 130 }
 131
 132 static unsigned long atm_tc_get(struct Qdisc *sch, u32 classid)
 133 {
 134         struct atm_qdisc_data *p __maybe_unused = PRIV(sch);
 135         struct atm_flow_data *flow;
 136
 137         DPRINTK("atm_tc_get(sch %p,[qdisc %p],classid %x)\n", sch, p, classid);
 138         flow = lookup_flow(sch, classid);
 139         if (flow)
 140                 flow->ref++;
 141         DPRINTK("atm_tc_get: flow %p\n", flow);
 142         return (unsigned long)flow;
 143 }
 144
 145 static unsigned long atm_tc_bind_filter(struct Qdisc *sch,
 146                                         unsigned long parent, u32 classid)
 147 {
 148         return atm_tc_get(sch, classid);
 149 }
 150
 151 /*
 152  * atm_tc_put handles all destructions, including the ones that are explicitly
 153  * requested (atm_tc_destroy, etc.). The assumption here is that we never drop
 154  * anything that still seems to be in use.
 155  */
 156 static void atm_tc_put(struct Qdisc *sch, unsigned long cl)
 157 {
 158         struct atm_qdisc_data *p = PRIV(sch);
 159         struct atm_flow_data *flow = (struct atm_flow_data *)cl;
 160         struct atm_flow_data **prev;
 161
 162         DPRINTK("atm_tc_put(sch %p,[qdisc %p],flow %p)\n", sch, p, flow);
 163         if (--flow->ref)
 164                 return;
 165         DPRINTK("atm_tc_put: destroying\n");
 166         for (prev = &p->flows; *prev; prev = &(*prev)->next)
 167                 if (*prev == flow)
 168                         break;
 169         if (!*prev) {
 170                 printk(KERN_CRIT "atm_tc_put: class %p not found\n", flow);
 171                 return;
 172         }
 173         *prev = flow->next;
 174         DPRINTK("atm_tc_put: qdisc %p\n", flow->q);
 175         qdisc_destroy(flow->q);
 176         tcf_destroy_chain(flow->filter_list);
 177         if (flow->sock) {
 178                 DPRINTK("atm_tc_put: f_count %d\n",
 179                         file_count(flow->sock->file));
 180                 flow->vcc->pop = flow->old_pop;
 181                 sockfd_put(flow->sock);
 182         }
 183         if (flow->excess)
 184                 atm_tc_put(sch, (unsigned long)flow->excess);
 185         if (flow != &p->link)
 186                 kfree(flow);
 187         /*
 188          * If flow == &p->link, the qdisc no longer works at this point and
 189          * needs to be removed. (By the caller of atm_tc_put.)
 190          */
 191 }
 192
 193 static void sch_atm_pop(struct atm_vcc *vcc, struct sk_buff *skb)
 194 {
 195         struct atm_qdisc_data *p = VCC2FLOW(vcc)->parent;
 196
 197         D2PRINTK("sch_atm_pop(vcc %p,skb %p,[qdisc %p])\n", vcc, skb, p);
 198         VCC2FLOW(vcc)->old_pop(vcc, skb);
 199         tasklet_schedule(&p->task);
 200 }
 201
 202 static const u8 llc_oui_ip[] = {
 203         0xaa,                   /* DSAP: non-ISO */
 204         0xaa,                   /* SSAP: non-ISO */
 205         0x03,                   /* Ctrl: Unnumbered Information Command PDU */
 206         0x00,                   /* OUI: EtherType */
 207         0x00, 0x00,
 208         0x08, 0x00
 209 };                              /* Ethertype IP (0800) */
 210
 211 static int atm_tc_change(struct Qdisc *sch, u32 classid, u32 parent,
 212                          struct rtattr **tca, unsigned long *arg)
 213 {
 214         struct atm_qdisc_data *p = PRIV(sch);
 215         struct atm_flow_data *flow = (struct atm_flow_data *)*arg;
 216         struct atm_flow_data *excess = NULL;
 217         struct rtattr *opt = tca[TCA_OPTIONS - 1];
 218         struct rtattr *tb[TCA_ATM_MAX];
 219         struct socket *sock;
 220         int fd, error, hdr_len;
 221         void *hdr;
 222
 223         DPRINTK("atm_tc_change(sch %p,[qdisc %p],classid %x,parent %x,"
 224                 "flow %p,opt %p)\n", sch, p, classid, parent, flow, opt);
 225         /*
 226          * The concept of parents doesn't apply for this qdisc.
 227          */
 228         if (parent && parent != TC_H_ROOT && parent != sch->handle)
 229                 return -EINVAL;
 230         /*
 231          * ATM classes cannot be changed. In order to change properties of the
 232          * ATM connection, that socket needs to be modified directly (via the
 233          * native ATM API. In order to send a flow to a different VC, the old
 234          * class needs to be removed and a new one added. (This may be changed
 235          * later.)
 236          */
 237         if (flow)
 238                 return -EBUSY;
 239         if (opt == NULL || rtattr_parse_nested(tb, TCA_ATM_MAX, opt))
 240                 return -EINVAL;
 241         if (!tb[TCA_ATM_FD - 1] || RTA_PAYLOAD(tb[TCA_ATM_FD - 1]) < sizeof(fd))
 242                 return -EINVAL;
 243         fd = *(int *)RTA_DATA(tb[TCA_ATM_FD - 1]);
 244         DPRINTK("atm_tc_change: fd %d\n", fd);
 245         if (tb[TCA_ATM_HDR - 1]) {
 246                 hdr_len = RTA_PAYLOAD(tb[TCA_ATM_HDR - 1]);
 247                 hdr = RTA_DATA(tb[TCA_ATM_HDR - 1]);
 248         } else {
 249                 hdr_len = RFC1483LLC_LEN;
 250                 hdr = NULL;     /* default LLC/SNAP for IP */
 251         }
 252         if (!tb[TCA_ATM_EXCESS - 1])
 253                 excess = NULL;
 254         else {
 255                 if (RTA_PAYLOAD(tb[TCA_ATM_EXCESS - 1]) != sizeof(u32))
 256                         return -EINVAL;
 257                 excess = (struct atm_flow_data *)
 258                         atm_tc_get(sch, *(u32 *)RTA_DATA(tb[TCA_ATM_EXCESS - 1]));
 259                 if (!excess)
 260                         return -ENOENT;
 261         }
 262         DPRINTK("atm_tc_change: type %d, payload %d, hdr_len %d\n",
 263                 opt->rta_type, RTA_PAYLOAD(opt), hdr_len);
 264         if (!(sock = sockfd_lookup(fd, &error)))
 265                 return error;   /* f_count++ */
 266         DPRINTK("atm_tc_change: f_count %d\n", file_count(sock->file));
 267         if (sock->ops->family != PF_ATMSVC && sock->ops->family != PF_ATMPVC) {
 268                 error = -EPROTOTYPE;
 269                 goto err_out;
 270         }
 271         /* @@@ should check if the socket is really operational or we'll crash
 272            on vcc->send */
 273         if (classid) {
 274                 if (TC_H_MAJ(classid ^ sch->handle)) {
 275                         DPRINTK("atm_tc_change: classid mismatch\n");
 276                         error = -EINVAL;
 277                         goto err_out;
 278                 }
 279                 if (find_flow(p, flow)) {
 280                         error = -EEXIST;
 281                         goto err_out;
 282                 }
 283         } else {
 284                 int i;
 285                 unsigned long cl;
 286
 287                 for (i = 1; i < 0x8000; i++) {
 288                         classid = TC_H_MAKE(sch->handle, 0x8000 | i);
 289                         if (!(cl = atm_tc_get(sch, classid)))
 290                                 break;
 291                         atm_tc_put(sch, cl);
 292                 }
 293         }
 294         DPRINTK("atm_tc_change: new id %x\n", classid);
 295         flow = kzalloc(sizeof(struct atm_flow_data) + hdr_len, GFP_KERNEL);
 296         DPRINTK("atm_tc_change: flow %p\n", flow);
 297         if (!flow) {
 298                 error = -ENOBUFS;
 299                 goto err_out;
 300         }
 301         flow->filter_list = NULL;
 302         if (!(flow->q = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops, classid)))
 303                 flow->q = &noop_qdisc;
 304         DPRINTK("atm_tc_change: qdisc %p\n", flow->q);
 305         flow->sock = sock;
 306         flow->vcc = ATM_SD(sock);       /* speedup */
 307         flow->vcc->user_back = flow;
 308         DPRINTK("atm_tc_change: vcc %p\n", flow->vcc);
 309         flow->old_pop = flow->vcc->pop;
 310         flow->parent = p;
 311         flow->vcc->pop = sch_atm_pop;
 312         flow->classid = classid;
 313         flow->ref = 1;
 314         flow->excess = excess;
 315         flow->next = p->link.next;
 316         p->link.next = flow;
 317         flow->hdr_len = hdr_len;
 318         if (hdr)
 319                 memcpy(flow->hdr, hdr, hdr_len);
 320         else
 321                 memcpy(flow->hdr, llc_oui_ip, sizeof(llc_oui_ip));
 322         *arg = (unsigned long)flow;
 323         return 0;
 324 err_out:
 325         if (excess)
 326                 atm_tc_put(sch, (unsigned long)excess);
 327         sockfd_put(sock);
 328         return error;
 329 }
 330
 331 static int atm_tc_delete(struct Qdisc *sch, unsigned long arg)
 332 {
 333         struct atm_qdisc_data *p = PRIV(sch);
 334         struct atm_flow_data *flow = (struct atm_flow_data *)arg;
 335
 336         DPRINTK("atm_tc_delete(sch %p,[qdisc %p],flow %p)\n", sch, p, flow);
 337         if (!find_flow(PRIV(sch), flow))
 338                 return -EINVAL;
 339         if (flow->filter_list || flow == &p->link)
 340                 return -EBUSY;
 341         /*
 342          * Reference count must be 2: one for "keepalive" (set at class
 343          * creation), and one for the reference held when calling delete.
 344          */
 345         if (flow->ref < 2) {
 346                 printk(KERN_ERR "atm_tc_delete: flow->ref == %d\n", flow->ref);
 347                 return -EINVAL;
 348         }
 349         if (flow->ref > 2)
 350                 return -EBUSY;  /* catch references via excess, etc. */
 351         atm_tc_put(sch, arg);
 352         return 0;
 353 }
 354
 355 static void atm_tc_walk(struct Qdisc *sch, struct qdisc_walker *walker)
 356 {
 357         struct atm_qdisc_data *p = PRIV(sch);
 358         struct atm_flow_data *flow;
 359
 360         DPRINTK("atm_tc_walk(sch %p,[qdisc %p],walker %p)\n", sch, p, walker);
 361         if (walker->stop)
 362                 return;
 363         for (flow = p->flows; flow; flow = flow->next) {
 364                 if (walker->count >= walker->skip)
 365                         if (walker->fn(sch, (unsigned long)flow, walker) < 0) {
 366                                 walker->stop = 1;
 367                                 break;
 368                         }
 369                 walker->count++;
 370         }
 371 }
 372
 373 static struct tcf_proto **atm_tc_find_tcf(struct Qdisc *sch, unsigned long cl)
 374 {
 375         struct atm_qdisc_data *p = PRIV(sch);
 376         struct atm_flow_data *flow = (struct atm_flow_data *)cl;
 377
 378         DPRINTK("atm_tc_find_tcf(sch %p,[qdisc %p],flow %p)\n", sch, p, flow);
 379         return flow ? &flow->filter_list : &p->link.filter_list;
 380 }
 381
 382 /* --------------------------- Qdisc operations ---------------------------- */
 383
 384 static int atm_tc_enqueue(struct sk_buff *skb, struct Qdisc *sch)
 385 {
 386         struct atm_qdisc_data *p = PRIV(sch);
 387         struct atm_flow_data *flow = NULL;      /* @@@ */
 388         struct tcf_result res;
 389         int result;
 390         int ret = NET_XMIT_POLICED;
 391
 392         D2PRINTK("atm_tc_enqueue(skb %p,sch %p,[qdisc %p])\n", skb, sch, p);
 393         result = TC_POLICE_OK;  /* be nice to gcc */
 394         if (TC_H_MAJ(skb->priority) != sch->handle ||
 395             !(flow = (struct atm_flow_data *)atm_tc_get(sch, skb->priority)))
 396                 for (flow = p->flows; flow; flow = flow->next)
 397                         if (flow->filter_list) {
 398                                 result = tc_classify_compat(skb,
 399                                                             flow->filter_list,
 400                                                             &res);
 401                                 if (result < 0)
 402                                         continue;
 403                                 flow = (struct atm_flow_data *)res.class;
 404                                 if (!flow)
 405                                         flow = lookup_flow(sch, res.classid);
 406                                 break;
 407                         }
 408         if (!flow)
 409                 flow = &p->link;
 410         else {
 411                 if (flow->vcc)
 412                         ATM_SKB(skb)->atm_options = flow->vcc->atm_options;
 413                 /*@@@ looks good ... but it's not supposed to work :-) */
 414 #ifdef CONFIG_NET_CLS_ACT
 415                 switch (result) {
 416                 case TC_ACT_QUEUED:
 417                 case TC_ACT_STOLEN:
 418                         kfree_skb(skb);
 419                         return NET_XMIT_SUCCESS;
 420                 case TC_ACT_SHOT:
 421                         kfree_skb(skb);
 422                         goto drop;
 423                 case TC_POLICE_RECLASSIFY:
 424                         if (flow->excess)
 425                                 flow = flow->excess;
 426                         else
 427                                 ATM_SKB(skb)->atm_options |= ATM_ATMOPT_CLP;
 428                         break;
 429                 }
 430 #endif
 431         }
 432
 433         if ((ret = flow->q->enqueue(skb, flow->q)) != 0) {
 434 drop: __maybe_unused
 435                 sch->qstats.drops++;
 436                 if (flow)
 437                         flow->qstats.drops++;
 438                 return ret;
 439         }
 440         sch->bstats.bytes += skb->len;
 441         sch->bstats.packets++;
 442         flow->bstats.bytes += skb->len;
 443         flow->bstats.packets++;
 444         /*
 445          * Okay, this may seem weird. We pretend we've dropped the packet if
 446          * it goes via ATM. The reason for this is that the outer qdisc
 447          * expects to be able to q->dequeue the packet later on if we return
 448          * success at this place. Also, sch->q.qdisc needs to reflect whether
 449          * there is a packet egligible for dequeuing or not. Note that the
 450          * statistics of the outer qdisc are necessarily wrong because of all
 451          * this. There's currently no correct solution for this.
 452          */
 453         if (flow == &p->link) {
 454                 sch->q.qlen++;
 455                 return 0;
 456         }
 457         tasklet_schedule(&p->task);
 458         return NET_XMIT_BYPASS;
 459 }
 460
 461 /*
 462  * Dequeue packets and send them over ATM. Note that we quite deliberately
 463  * avoid checking net_device's flow control here, simply because sch_atm
 464  * uses its own channels, which have nothing to do with any CLIP/LANE/or
 465  * non-ATM interfaces.
 466  */
 467
 468 static void sch_atm_dequeue(unsigned long data)
 469 {
 470         struct Qdisc *sch = (struct Qdisc *)data;
 471         struct atm_qdisc_data *p = PRIV(sch);
 472         struct atm_flow_data *flow;
 473         struct sk_buff *skb;
 474
 475         D2PRINTK("sch_atm_dequeue(sch %p,[qdisc %p])\n", sch, p);
 476         for (flow = p->link.next; flow; flow = flow->next)
 477                 /*
 478                  * If traffic is properly shaped, this won't generate nasty
 479                  * little bursts. Otherwise, it may ... (but that's okay)
 480                  */
 481                 while ((skb = flow->q->dequeue(flow->q))) {
 482                         if (!atm_may_send(flow->vcc, skb->truesize)) {
 483                                 (void)flow->q->ops->requeue(skb, flow->q);
 484                                 break;
 485                         }
 486                         D2PRINTK("atm_tc_dequeue: sending on class %p\n", flow);
 487                         /* remove any LL header somebody else has attached */
 488                         skb_pull(skb, skb_network_offset(skb));
 489                         if (skb_headroom(skb) < flow->hdr_len) {
 490                                 struct sk_buff *new;
 491
 492                                 new = skb_realloc_headroom(skb, flow->hdr_len);
 493                                 dev_kfree_skb(skb);
 494                                 if (!new)
 495                                         continue;
 496                                 skb = new;
 497                         }
 498                         D2PRINTK("sch_atm_dequeue: ip %p, data %p\n",
 499                                  skb_network_header(skb), skb->data);
 500                         ATM_SKB(skb)->vcc = flow->vcc;
 501                         memcpy(skb_push(skb, flow->hdr_len), flow->hdr,
 502                                flow->hdr_len);
 503                         atomic_add(skb->truesize,
 504                                    &sk_atm(flow->vcc)->sk_wmem_alloc);
 505                         /* atm.atm_options are already set by atm_tc_enqueue */
 506                         flow->vcc->send(flow->vcc, skb);
 507                 }
 508 }
 509
 510 static struct sk_buff *atm_tc_dequeue(struct Qdisc *sch)
 511 {
 512         struct atm_qdisc_data *p = PRIV(sch);
 513         struct sk_buff *skb;
 514
 515         D2PRINTK("atm_tc_dequeue(sch %p,[qdisc %p])\n", sch, p);
 516         tasklet_schedule(&p->task);
 517         skb = p->link.q->dequeue(p->link.q);
 518         if (skb)
 519                 sch->q.qlen--;
 520         return skb;
 521 }
 522
 523 static int atm_tc_requeue(struct sk_buff *skb, struct Qdisc *sch)
 524 {
 525         struct atm_qdisc_data *p = PRIV(sch);
 526         int ret;
 527
 528         D2PRINTK("atm_tc_requeue(skb %p,sch %p,[qdisc %p])\n", skb, sch, p);
 529         ret = p->link.q->ops->requeue(skb, p->link.q);
 530         if (!ret) {
 531                 sch->q.qlen++;
 532                 sch->qstats.requeues++;
 533         } else {
 534                 sch->qstats.drops++;
 535                 p->link.qstats.drops++;
 536         }
 537         return ret;
 538 }
 539
 540 static unsigned int atm_tc_drop(struct Qdisc *sch)
 541 {
 542         struct atm_qdisc_data *p = PRIV(sch);
 543         struct atm_flow_data *flow;
 544         unsigned int len;
 545
 546         DPRINTK("atm_tc_drop(sch %p,[qdisc %p])\n", sch, p);
 547         for (flow = p->flows; flow; flow = flow->next)
 548                 if (flow->q->ops->drop && (len = flow->q->ops->drop(flow->q)))
 549                         return len;
 550         return 0;
 551 }
 552
 553 static int atm_tc_init(struct Qdisc *sch, struct rtattr *opt)
 554 {
 555         struct atm_qdisc_data *p = PRIV(sch);
 556
 557         DPRINTK("atm_tc_init(sch %p,[qdisc %p],opt %p)\n", sch, p, opt);
 558         p->flows = &p->link;
 559         if (!(p->link.q = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops,
 560                                             sch->handle)))
 561                 p->link.q = &noop_qdisc;
 562         DPRINTK("atm_tc_init: link (%p) qdisc %p\n", &p->link, p->link.q);
 563         p->link.filter_list = NULL;
 564         p->link.vcc = NULL;
 565         p->link.sock = NULL;
 566         p->link.classid = sch->handle;
 567         p->link.ref = 1;
 568         p->link.next = NULL;
 569         tasklet_init(&p->task, sch_atm_dequeue, (unsigned long)sch);
 570         return 0;
 571 }
 572
 573 static void atm_tc_reset(struct Qdisc *sch)
 574 {
 575         struct atm_qdisc_data *p = PRIV(sch);
 576         struct atm_flow_data *flow;
 577
 578         DPRINTK("atm_tc_reset(sch %p,[qdisc %p])\n", sch, p);
 579         for (flow = p->flows; flow; flow = flow->next)
 580                 qdisc_reset(flow->q);
 581         sch->q.qlen = 0;
 582 }
 583
 584 static void atm_tc_destroy(struct Qdisc *sch)
 585 {
 586         struct atm_qdisc_data *p = PRIV(sch);
 587         struct atm_flow_data *flow;
 588
 589         DPRINTK("atm_tc_destroy(sch %p,[qdisc %p])\n", sch, p);
 590         /* races ? */
 591         while ((flow = p->flows)) {
 592                 tcf_destroy_chain(flow->filter_list);
 593                 flow->filter_list = NULL;
 594                 if (flow->ref > 1)
 595                         printk(KERN_ERR "atm_destroy: %p->ref = %d\n", flow,
 596                                flow->ref);
 597                 atm_tc_put(sch, (unsigned long)flow);
 598                 if (p->flows == flow) {
 599                         printk(KERN_ERR "atm_destroy: putting flow %p didn't "
 600                                "kill it\n", flow);
 601                         p->flows = flow->next;  /* brute force */
 602                         break;
 603                 }
 604         }
 605         tasklet_kill(&p->task);
 606 }
 607
 608 static int atm_tc_dump_class(struct Qdisc *sch, unsigned long cl,
 609                              struct sk_buff *skb, struct tcmsg *tcm)
 610 {
 611         struct atm_qdisc_data *p = PRIV(sch);
 612         struct atm_flow_data *flow = (struct atm_flow_data *)cl;
 613         unsigned char *b = skb_tail_pointer(skb);
 614         struct rtattr *rta;
 615
 616         DPRINTK("atm_tc_dump_class(sch %p,[qdisc %p],flow %p,skb %p,tcm %p)\n",
 617                 sch, p, flow, skb, tcm);
 618         if (!find_flow(p, flow))
 619                 return -EINVAL;
 620         tcm->tcm_handle = flow->classid;
 621         tcm->tcm_info = flow->q->handle;
 622         rta = (struct rtattr *)b;
 623         RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
 624         RTA_PUT(skb, TCA_ATM_HDR, flow->hdr_len, flow->hdr);
 625         if (flow->vcc) {
 626                 struct sockaddr_atmpvc pvc;
 627                 int state;
 628
 629                 pvc.sap_family = AF_ATMPVC;
 630                 pvc.sap_addr.itf = flow->vcc->dev ? flow->vcc->dev->number : -1;
 631                 pvc.sap_addr.vpi = flow->vcc->vpi;
 632                 pvc.sap_addr.vci = flow->vcc->vci;
 633                 RTA_PUT(skb, TCA_ATM_ADDR, sizeof(pvc), &pvc);
 634                 state = ATM_VF2VS(flow->vcc->flags);
 635                 RTA_PUT(skb, TCA_ATM_STATE, sizeof(state), &state);
 636         }
 637         if (flow->excess)
 638                 RTA_PUT(skb, TCA_ATM_EXCESS, sizeof(u32), &flow->classid);
 639         else {
 640                 static u32 zero;
 641
 642                 RTA_PUT(skb, TCA_ATM_EXCESS, sizeof(zero), &zero);
 643         }
 644         rta->rta_len = skb_tail_pointer(skb) - b;
 645         return skb->len;
 646
 647 rtattr_failure:
 648         nlmsg_trim(skb, b);
 649         return -1;
 650 }
 651 static int
 652 atm_tc_dump_class_stats(struct Qdisc *sch, unsigned long arg,
 653                         struct gnet_dump *d)
 654 {
 655         struct atm_flow_data *flow = (struct atm_flow_data *)arg;
 656
 657         flow->qstats.qlen = flow->q->q.qlen;
 658
 659         if (gnet_stats_copy_basic(d, &flow->bstats) < 0 ||
 660             gnet_stats_copy_queue(d, &flow->qstats) < 0)
 661                 return -1;
 662
 663         return 0;
 664 }
 665
 666 static int atm_tc_dump(struct Qdisc *sch, struct sk_buff *skb)
 667 {
 668         return 0;
 669 }
 670
 671 static const struct Qdisc_class_ops atm_class_ops = {
 672         .graft          = atm_tc_graft,
 673         .leaf           = atm_tc_leaf,
 674         .get            = atm_tc_get,
 675         .put            = atm_tc_put,
 676         .change         = atm_tc_change,
 677         .delete         = atm_tc_delete,
 678         .walk           = atm_tc_walk,
 679         .tcf_chain      = atm_tc_find_tcf,
 680         .bind_tcf       = atm_tc_bind_filter,
 681         .unbind_tcf     = atm_tc_put,
 682         .dump           = atm_tc_dump_class,
 683         .dump_stats     = atm_tc_dump_class_stats,
 684 };
 685
 686 static struct Qdisc_ops atm_qdisc_ops __read_mostly = {
 687         .cl_ops         = &atm_class_ops,
 688         .id             = "atm",
 689         .priv_size      = sizeof(struct atm_qdisc_data),
 690         .enqueue        = atm_tc_enqueue,
 691         .dequeue        = atm_tc_dequeue,
 692         .requeue        = atm_tc_requeue,
 693         .drop           = atm_tc_drop,
 694         .init           = atm_tc_init,
 695         .reset          = atm_tc_reset,
 696         .destroy        = atm_tc_destroy,
 697         .dump           = atm_tc_dump,
 698         .owner          = THIS_MODULE,
 699 };
 700
 701 static int __init atm_init(void)
 702 {
 703         return register_qdisc(&atm_qdisc_ops);
 704 }
 705
 706 static void __exit atm_exit(void)
 707 {
 708         unregister_qdisc(&atm_qdisc_ops);
 709 }
 710
 711 module_init(atm_init)
 712 module_exit(atm_exit)
 713 MODULE_LICENSE("GPL");