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/slab.h>
   7 #include <linux/init.h>
   8 #include <linux/interrupt.h>
   9 #include <linux/string.h>
  10 #include <linux/errno.h>
  11 #include <linux/skbuff.h>
  12 #include <linux/atmdev.h>
  13 #include <linux/atmclip.h>
  14 #include <linux/rtnetlink.h>
  15 #include <linux/file.h>         /* for fput */
  16 #include <net/netlink.h>
  17 #include <net/pkt_sched.h>
  18 #include <net/pkt_cls.h>
  19
  20 /*
  21  * The ATM queuing discipline provides a framework for invoking classifiers
  22  * (aka "filters"), which in turn select classes of this queuing discipline.
  23  * Each class maps the flow(s) it is handling to a given VC. Multiple classes
  24  * may share the same VC.
  25  *
  26  * When creating a class, VCs are specified by passing the number of the open
  27  * socket descriptor by which the calling process references the VC. The kernel
  28  * keeps the VC open at least until all classes using it are removed.
  29  *
  30  * In this file, most functions are named atm_tc_* to avoid confusion with all
  31  * the atm_* in net/atm. This naming convention differs from what's used in the
  32  * rest of net/sched.
  33  *
  34  * Known bugs:
  35  *  - sometimes messes up the IP stack
  36  *  - any manipulations besides the few operations described in the README, are
  37  *    untested and likely to crash the system
  38  *  - should lock the flow while there is data in the queue (?)
  39  */
  40
  41 #define VCC2FLOW(vcc) ((struct atm_flow_data *) ((vcc)->user_back))
  42
  43 struct atm_flow_data {
  44         struct Qdisc            *q;     /* FIFO, TBF, etc. */
  45         struct tcf_proto __rcu  *filter_list;
  46         struct tcf_block        *block;
  47         struct atm_vcc          *vcc;   /* VCC; NULL if VCC is closed */
  48         void                    (*old_pop)(struct atm_vcc *vcc,
  49                                            struct sk_buff *skb); /* chaining */
  50         struct atm_qdisc_data   *parent;        /* parent qdisc */
  51         struct socket           *sock;          /* for closing */
  52         u32                     classid;        /* x:y type ID */
  53         int                     ref;            /* reference count */
  54         struct gnet_stats_basic_packed  bstats;
  55         struct gnet_stats_queue qstats;
  56         struct list_head        list;
  57         struct atm_flow_data    *excess;        /* flow for excess traffic;
  58                                                    NULL to set CLP instead */
  59         int                     hdr_len;
  60         unsigned char           hdr[0];         /* header data; MUST BE LAST */
  61 };
  62
  63 struct atm_qdisc_data {
  64         struct atm_flow_data    link;           /* unclassified skbs go here */
  65         struct list_head        flows;          /* NB: "link" is also on this
  66                                                    list */
  67         struct tasklet_struct   task;           /* dequeue tasklet */
  68 };
  69
  70 /* ------------------------- Class/flow operations ------------------------- */
  71
  72 static inline struct atm_flow_data *lookup_flow(struct Qdisc *sch, u32 classid)
  73 {
  74         struct atm_qdisc_data *p = qdisc_priv(sch);
  75         struct atm_flow_data *flow;
  76
  77         list_for_each_entry(flow, &p->flows, list) {
  78                 if (flow->classid == classid)
  79                         return flow;
  80         }
  81         return NULL;
  82 }
  83
  84 static int atm_tc_graft(struct Qdisc *sch, unsigned long arg,
  85                         struct Qdisc *new, struct Qdisc **old)
  86 {
  87         struct atm_qdisc_data *p = qdisc_priv(sch);
  88         struct atm_flow_data *flow = (struct atm_flow_data *)arg;
  89
  90         pr_debug("atm_tc_graft(sch %p,[qdisc %p],flow %p,new %p,old %p)\n",
  91                 sch, p, flow, new, old);
  92         if (list_empty(&flow->list))
  93                 return -EINVAL;
  94         if (!new)
  95                 new = &noop_qdisc;
  96         *old = flow->q;
  97         flow->q = new;
  98         if (*old)
  99                 qdisc_reset(*old);
 100         return 0;
 101 }
 102
 103 static struct Qdisc *atm_tc_leaf(struct Qdisc *sch, unsigned long cl)
 104 {
 105         struct atm_flow_data *flow = (struct atm_flow_data *)cl;
 106
 107         pr_debug("atm_tc_leaf(sch %p,flow %p)\n", sch, flow);
 108         return flow ? flow->q : NULL;
 109 }
 110
 111 static unsigned long atm_tc_get(struct Qdisc *sch, u32 classid)
 112 {
 113         struct atm_qdisc_data *p __maybe_unused = qdisc_priv(sch);
 114         struct atm_flow_data *flow;
 115
 116         pr_debug("atm_tc_get(sch %p,[qdisc %p],classid %x)\n", sch, p, classid);
 117         flow = lookup_flow(sch, classid);
 118         if (flow)
 119                 flow->ref++;
 120         pr_debug("atm_tc_get: flow %p\n", flow);
 121         return (unsigned long)flow;
 122 }
 123
 124 static unsigned long atm_tc_bind_filter(struct Qdisc *sch,
 125                                         unsigned long parent, u32 classid)
 126 {
 127         return atm_tc_get(sch, classid);
 128 }
 129
 130 /*
 131  * atm_tc_put handles all destructions, including the ones that are explicitly
 132  * requested (atm_tc_destroy, etc.). The assumption here is that we never drop
 133  * anything that still seems to be in use.
 134  */
 135 static void atm_tc_put(struct Qdisc *sch, unsigned long cl)
 136 {
 137         struct atm_qdisc_data *p = qdisc_priv(sch);
 138         struct atm_flow_data *flow = (struct atm_flow_data *)cl;
 139
 140         pr_debug("atm_tc_put(sch %p,[qdisc %p],flow %p)\n", sch, p, flow);
 141         if (--flow->ref)
 142                 return;
 143         pr_debug("atm_tc_put: destroying\n");
 144         list_del_init(&flow->list);
 145         pr_debug("atm_tc_put: qdisc %p\n", flow->q);
 146         qdisc_destroy(flow->q);
 147         tcf_block_put(flow->block);
 148         if (flow->sock) {
 149                 pr_debug("atm_tc_put: f_count %ld\n",
 150                         file_count(flow->sock->file));
 151                 flow->vcc->pop = flow->old_pop;
 152                 sockfd_put(flow->sock);
 153         }
 154         if (flow->excess)
 155                 atm_tc_put(sch, (unsigned long)flow->excess);
 156         if (flow != &p->link)
 157                 kfree(flow);
 158         /*
 159          * If flow == &p->link, the qdisc no longer works at this point and
 160          * needs to be removed. (By the caller of atm_tc_put.)
 161          */
 162 }
 163
 164 static void sch_atm_pop(struct atm_vcc *vcc, struct sk_buff *skb)
 165 {
 166         struct atm_qdisc_data *p = VCC2FLOW(vcc)->parent;
 167
 168         pr_debug("sch_atm_pop(vcc %p,skb %p,[qdisc %p])\n", vcc, skb, p);
 169         VCC2FLOW(vcc)->old_pop(vcc, skb);
 170         tasklet_schedule(&p->task);
 171 }
 172
 173 static const u8 llc_oui_ip[] = {
 174         0xaa,                   /* DSAP: non-ISO */
 175         0xaa,                   /* SSAP: non-ISO */
 176         0x03,                   /* Ctrl: Unnumbered Information Command PDU */
 177         0x00,                   /* OUI: EtherType */
 178         0x00, 0x00,
 179         0x08, 0x00
 180 };                              /* Ethertype IP (0800) */
 181
 182 static const struct nla_policy atm_policy[TCA_ATM_MAX + 1] = {
 183         [TCA_ATM_FD]            = { .type = NLA_U32 },
 184         [TCA_ATM_EXCESS]        = { .type = NLA_U32 },
 185 };
 186
 187 static int atm_tc_change(struct Qdisc *sch, u32 classid, u32 parent,
 188                          struct nlattr **tca, unsigned long *arg)
 189 {
 190         struct atm_qdisc_data *p = qdisc_priv(sch);
 191         struct atm_flow_data *flow = (struct atm_flow_data *)*arg;
 192         struct atm_flow_data *excess = NULL;
 193         struct nlattr *opt = tca[TCA_OPTIONS];
 194         struct nlattr *tb[TCA_ATM_MAX + 1];
 195         struct socket *sock;
 196         int fd, error, hdr_len;
 197         void *hdr;
 198
 199         pr_debug("atm_tc_change(sch %p,[qdisc %p],classid %x,parent %x,"
 200                 "flow %p,opt %p)\n", sch, p, classid, parent, flow, opt);
 201         /*
 202          * The concept of parents doesn't apply for this qdisc.
 203          */
 204         if (parent && parent != TC_H_ROOT && parent != sch->handle)
 205                 return -EINVAL;
 206         /*
 207          * ATM classes cannot be changed. In order to change properties of the
 208          * ATM connection, that socket needs to be modified directly (via the
 209          * native ATM API. In order to send a flow to a different VC, the old
 210          * class needs to be removed and a new one added. (This may be changed
 211          * later.)
 212          */
 213         if (flow)
 214                 return -EBUSY;
 215         if (opt == NULL)
 216                 return -EINVAL;
 217
 218         error = nla_parse_nested(tb, TCA_ATM_MAX, opt, atm_policy, NULL);
 219         if (error < 0)
 220                 return error;
 221
 222         if (!tb[TCA_ATM_FD])
 223                 return -EINVAL;
 224         fd = nla_get_u32(tb[TCA_ATM_FD]);
 225         pr_debug("atm_tc_change: fd %d\n", fd);
 226         if (tb[TCA_ATM_HDR]) {
 227                 hdr_len = nla_len(tb[TCA_ATM_HDR]);
 228                 hdr = nla_data(tb[TCA_ATM_HDR]);
 229         } else {
 230                 hdr_len = RFC1483LLC_LEN;
 231                 hdr = NULL;     /* default LLC/SNAP for IP */
 232         }
 233         if (!tb[TCA_ATM_EXCESS])
 234                 excess = NULL;
 235         else {
 236                 excess = (struct atm_flow_data *)
 237                         atm_tc_get(sch, nla_get_u32(tb[TCA_ATM_EXCESS]));
 238                 if (!excess)
 239                         return -ENOENT;
 240         }
 241         pr_debug("atm_tc_change: type %d, payload %d, hdr_len %d\n",
 242                  opt->nla_type, nla_len(opt), hdr_len);
 243         sock = sockfd_lookup(fd, &error);
 244         if (!sock)
 245                 return error;   /* f_count++ */
 246         pr_debug("atm_tc_change: f_count %ld\n", file_count(sock->file));
 247         if (sock->ops->family != PF_ATMSVC && sock->ops->family != PF_ATMPVC) {
 248                 error = -EPROTOTYPE;
 249                 goto err_out;
 250         }
 251         /* @@@ should check if the socket is really operational or we'll crash
 252            on vcc->send */
 253         if (classid) {
 254                 if (TC_H_MAJ(classid ^ sch->handle)) {
 255                         pr_debug("atm_tc_change: classid mismatch\n");
 256                         error = -EINVAL;
 257                         goto err_out;
 258                 }
 259         } else {
 260                 int i;
 261                 unsigned long cl;
 262
 263                 for (i = 1; i < 0x8000; i++) {
 264                         classid = TC_H_MAKE(sch->handle, 0x8000 | i);
 265                         cl = atm_tc_get(sch, classid);
 266                         if (!cl)
 267                                 break;
 268                         atm_tc_put(sch, cl);
 269                 }
 270         }
 271         pr_debug("atm_tc_change: new id %x\n", classid);
 272         flow = kzalloc(sizeof(struct atm_flow_data) + hdr_len, GFP_KERNEL);
 273         pr_debug("atm_tc_change: flow %p\n", flow);
 274         if (!flow) {
 275                 error = -ENOBUFS;
 276                 goto err_out;
 277         }
 278
 279         error = tcf_block_get(&flow->block, &flow->filter_list);
 280         if (error) {
 281                 kfree(flow);
 282                 goto err_out;
 283         }
 284
 285         flow->q = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops, classid);
 286         if (!flow->q)
 287                 flow->q = &noop_qdisc;
 288         pr_debug("atm_tc_change: qdisc %p\n", flow->q);
 289         flow->sock = sock;
 290         flow->vcc = ATM_SD(sock);       /* speedup */
 291         flow->vcc->user_back = flow;
 292         pr_debug("atm_tc_change: vcc %p\n", flow->vcc);
 293         flow->old_pop = flow->vcc->pop;
 294         flow->parent = p;
 295         flow->vcc->pop = sch_atm_pop;
 296         flow->classid = classid;
 297         flow->ref = 1;
 298         flow->excess = excess;
 299         list_add(&flow->list, &p->link.list);
 300         flow->hdr_len = hdr_len;
 301         if (hdr)
 302                 memcpy(flow->hdr, hdr, hdr_len);
 303         else
 304                 memcpy(flow->hdr, llc_oui_ip, sizeof(llc_oui_ip));
 305         *arg = (unsigned long)flow;
 306         return 0;
 307 err_out:
 308         if (excess)
 309                 atm_tc_put(sch, (unsigned long)excess);
 310         sockfd_put(sock);
 311         return error;
 312 }
 313
 314 static int atm_tc_delete(struct Qdisc *sch, unsigned long arg)
 315 {
 316         struct atm_qdisc_data *p = qdisc_priv(sch);
 317         struct atm_flow_data *flow = (struct atm_flow_data *)arg;
 318
 319         pr_debug("atm_tc_delete(sch %p,[qdisc %p],flow %p)\n", sch, p, flow);
 320         if (list_empty(&flow->list))
 321                 return -EINVAL;
 322         if (rcu_access_pointer(flow->filter_list) || flow == &p->link)
 323                 return -EBUSY;
 324         /*
 325          * Reference count must be 2: one for "keepalive" (set at class
 326          * creation), and one for the reference held when calling delete.
 327          */
 328         if (flow->ref < 2) {
 329                 pr_err("atm_tc_delete: flow->ref == %d\n", flow->ref);
 330                 return -EINVAL;
 331         }
 332         if (flow->ref > 2)
 333                 return -EBUSY;  /* catch references via excess, etc. */
 334         atm_tc_put(sch, arg);
 335         return 0;
 336 }
 337
 338 static void atm_tc_walk(struct Qdisc *sch, struct qdisc_walker *walker)
 339 {
 340         struct atm_qdisc_data *p = qdisc_priv(sch);
 341         struct atm_flow_data *flow;
 342
 343         pr_debug("atm_tc_walk(sch %p,[qdisc %p],walker %p)\n", sch, p, walker);
 344         if (walker->stop)
 345                 return;
 346         list_for_each_entry(flow, &p->flows, list) {
 347                 if (walker->count >= walker->skip &&
 348                     walker->fn(sch, (unsigned long)flow, walker) < 0) {
 349                         walker->stop = 1;
 350                         break;
 351                 }
 352                 walker->count++;
 353         }
 354 }
 355
 356 static struct tcf_block *atm_tc_tcf_block(struct Qdisc *sch, unsigned long cl)
 357 {
 358         struct atm_qdisc_data *p = qdisc_priv(sch);
 359         struct atm_flow_data *flow = (struct atm_flow_data *)cl;
 360
 361         pr_debug("atm_tc_find_tcf(sch %p,[qdisc %p],flow %p)\n", sch, p, flow);
 362         return flow ? flow->block : p->link.block;
 363 }
 364
 365 /* --------------------------- Qdisc operations ---------------------------- */
 366
 367 static int atm_tc_enqueue(struct sk_buff *skb, struct Qdisc *sch,
 368                           struct sk_buff **to_free)
 369 {
 370         struct atm_qdisc_data *p = qdisc_priv(sch);
 371         struct atm_flow_data *flow;
 372         struct tcf_result res;
 373         int result;
 374         int ret = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
 375
 376         pr_debug("atm_tc_enqueue(skb %p,sch %p,[qdisc %p])\n", skb, sch, p);
 377         result = TC_ACT_OK;     /* be nice to gcc */
 378         flow = NULL;
 379         if (TC_H_MAJ(skb->priority) != sch->handle ||
 380             !(flow = (struct atm_flow_data *)atm_tc_get(sch, skb->priority))) {
 381                 struct tcf_proto *fl;
 382
 383                 list_for_each_entry(flow, &p->flows, list) {
 384                         fl = rcu_dereference_bh(flow->filter_list);
 385                         if (fl) {
 386                                 result = tcf_classify(skb, fl, &res, true);
 387                                 if (result < 0)
 388                                         continue;
 389                                 flow = (struct atm_flow_data *)res.class;
 390                                 if (!flow)
 391                                         flow = lookup_flow(sch, res.classid);
 392                                 goto done;
 393                         }
 394                 }
 395                 flow = NULL;
 396 done:
 397                 ;
 398         }
 399         if (!flow) {
 400                 flow = &p->link;
 401         } else {
 402                 if (flow->vcc)
 403                         ATM_SKB(skb)->atm_options = flow->vcc->atm_options;
 404                 /*@@@ looks good ... but it's not supposed to work :-) */
 405 #ifdef CONFIG_NET_CLS_ACT
 406                 switch (result) {
 407                 case TC_ACT_QUEUED:
 408                 case TC_ACT_STOLEN:
 409                 case TC_ACT_TRAP:
 410                         __qdisc_drop(skb, to_free);
 411                         return NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
 412                 case TC_ACT_SHOT:
 413                         __qdisc_drop(skb, to_free);
 414                         goto drop;
 415                 case TC_ACT_RECLASSIFY:
 416                         if (flow->excess)
 417                                 flow = flow->excess;
 418                         else
 419                                 ATM_SKB(skb)->atm_options |= ATM_ATMOPT_CLP;
 420                         break;
 421                 }
 422 #endif
 423         }
 424
 425         ret = qdisc_enqueue(skb, flow->q, to_free);
 426         if (ret != NET_XMIT_SUCCESS) {
 427 drop: __maybe_unused
 428                 if (net_xmit_drop_count(ret)) {
 429                         qdisc_qstats_drop(sch);
 430                         if (flow)
 431                                 flow->qstats.drops++;
 432                 }
 433                 return ret;
 434         }
 435         /*
 436          * Okay, this may seem weird. We pretend we've dropped the packet if
 437          * it goes via ATM. The reason for this is that the outer qdisc
 438          * expects to be able to q->dequeue the packet later on if we return
 439          * success at this place. Also, sch->q.qdisc needs to reflect whether
 440          * there is a packet egligible for dequeuing or not. Note that the
 441          * statistics of the outer qdisc are necessarily wrong because of all
 442          * this. There's currently no correct solution for this.
 443          */
 444         if (flow == &p->link) {
 445                 sch->q.qlen++;
 446                 return NET_XMIT_SUCCESS;
 447         }
 448         tasklet_schedule(&p->task);
 449         return NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
 450 }
 451
 452 /*
 453  * Dequeue packets and send them over ATM. Note that we quite deliberately
 454  * avoid checking net_device's flow control here, simply because sch_atm
 455  * uses its own channels, which have nothing to do with any CLIP/LANE/or
 456  * non-ATM interfaces.
 457  */
 458
 459 static void sch_atm_dequeue(unsigned long data)
 460 {
 461         struct Qdisc *sch = (struct Qdisc *)data;
 462         struct atm_qdisc_data *p = qdisc_priv(sch);
 463         struct atm_flow_data *flow;
 464         struct sk_buff *skb;
 465
 466         pr_debug("sch_atm_dequeue(sch %p,[qdisc %p])\n", sch, p);
 467         list_for_each_entry(flow, &p->flows, list) {
 468                 if (flow == &p->link)
 469                         continue;
 470                 /*
 471                  * If traffic is properly shaped, this won't generate nasty
 472                  * little bursts. Otherwise, it may ... (but that's okay)
 473                  */
 474                 while ((skb = flow->q->ops->peek(flow->q))) {
 475                         if (!atm_may_send(flow->vcc, skb->truesize))
 476                                 break;
 477
 478                         skb = qdisc_dequeue_peeked(flow->q);
 479                         if (unlikely(!skb))
 480                                 break;
 481
 482                         qdisc_bstats_update(sch, skb);
 483                         bstats_update(&flow->bstats, skb);
 484                         pr_debug("atm_tc_dequeue: sending on class %p\n", flow);
 485                         /* remove any LL header somebody else has attached */
 486                         skb_pull(skb, skb_network_offset(skb));
 487                         if (skb_headroom(skb) < flow->hdr_len) {
 488                                 struct sk_buff *new;
 489
 490                                 new = skb_realloc_headroom(skb, flow->hdr_len);
 491                                 dev_kfree_skb(skb);
 492                                 if (!new)
 493                                         continue;
 494                                 skb = new;
 495                         }
 496                         pr_debug("sch_atm_dequeue: ip %p, data %p\n",
 497                                  skb_network_header(skb), skb->data);
 498                         ATM_SKB(skb)->vcc = flow->vcc;
 499                         memcpy(skb_push(skb, flow->hdr_len), flow->hdr,
 500                                flow->hdr_len);
 501                         refcount_add(skb->truesize,
 502                                    &sk_atm(flow->vcc)->sk_wmem_alloc);
 503                         /* atm.atm_options are already set by atm_tc_enqueue */
 504                         flow->vcc->send(flow->vcc, skb);
 505                 }
 506         }
 507 }
 508
 509 static struct sk_buff *atm_tc_dequeue(struct Qdisc *sch)
 510 {
 511         struct atm_qdisc_data *p = qdisc_priv(sch);
 512         struct sk_buff *skb;
 513
 514         pr_debug("atm_tc_dequeue(sch %p,[qdisc %p])\n", sch, p);
 515         tasklet_schedule(&p->task);
 516         skb = qdisc_dequeue_peeked(p->link.q);
 517         if (skb)
 518                 sch->q.qlen--;
 519         return skb;
 520 }
 521
 522 static struct sk_buff *atm_tc_peek(struct Qdisc *sch)
 523 {
 524         struct atm_qdisc_data *p = qdisc_priv(sch);
 525
 526         pr_debug("atm_tc_peek(sch %p,[qdisc %p])\n", sch, p);
 527
 528         return p->link.q->ops->peek(p->link.q);
 529 }
 530
 531 static int atm_tc_init(struct Qdisc *sch, struct nlattr *opt)
 532 {
 533         struct atm_qdisc_data *p = qdisc_priv(sch);
 534         int err;
 535
 536         pr_debug("atm_tc_init(sch %p,[qdisc %p],opt %p)\n", sch, p, opt);
 537         INIT_LIST_HEAD(&p->flows);
 538         INIT_LIST_HEAD(&p->link.list);
 539         list_add(&p->link.list, &p->flows);
 540         p->link.q = qdisc_create_dflt(sch->dev_queue,
 541                                       &pfifo_qdisc_ops, sch->handle);
 542         if (!p->link.q)
 543                 p->link.q = &noop_qdisc;
 544         pr_debug("atm_tc_init: link (%p) qdisc %p\n", &p->link, p->link.q);
 545
 546         err = tcf_block_get(&p->link.block, &p->link.filter_list);
 547         if (err)
 548                 return err;
 549
 550         p->link.vcc = NULL;
 551         p->link.sock = NULL;
 552         p->link.classid = sch->handle;
 553         p->link.ref = 1;
 554         tasklet_init(&p->task, sch_atm_dequeue, (unsigned long)sch);
 555         return 0;
 556 }
 557
 558 static void atm_tc_reset(struct Qdisc *sch)
 559 {
 560         struct atm_qdisc_data *p = qdisc_priv(sch);
 561         struct atm_flow_data *flow;
 562
 563         pr_debug("atm_tc_reset(sch %p,[qdisc %p])\n", sch, p);
 564         list_for_each_entry(flow, &p->flows, list)
 565                 qdisc_reset(flow->q);
 566         sch->q.qlen = 0;
 567 }
 568
 569 static void atm_tc_destroy(struct Qdisc *sch)
 570 {
 571         struct atm_qdisc_data *p = qdisc_priv(sch);
 572         struct atm_flow_data *flow, *tmp;
 573
 574         pr_debug("atm_tc_destroy(sch %p,[qdisc %p])\n", sch, p);
 575         list_for_each_entry(flow, &p->flows, list)
 576                 tcf_block_put(flow->block);
 577
 578         list_for_each_entry_safe(flow, tmp, &p->flows, list) {
 579                 if (flow->ref > 1)
 580                         pr_err("atm_destroy: %p->ref = %d\n", flow, flow->ref);
 581                 atm_tc_put(sch, (unsigned long)flow);
 582         }
 583         tasklet_kill(&p->task);
 584 }
 585
 586 static int atm_tc_dump_class(struct Qdisc *sch, unsigned long cl,
 587                              struct sk_buff *skb, struct tcmsg *tcm)
 588 {
 589         struct atm_qdisc_data *p = qdisc_priv(sch);
 590         struct atm_flow_data *flow = (struct atm_flow_data *)cl;
 591         struct nlattr *nest;
 592
 593         pr_debug("atm_tc_dump_class(sch %p,[qdisc %p],flow %p,skb %p,tcm %p)\n",
 594                 sch, p, flow, skb, tcm);
 595         if (list_empty(&flow->list))
 596                 return -EINVAL;
 597         tcm->tcm_handle = flow->classid;
 598         tcm->tcm_info = flow->q->handle;
 599
 600         nest = nla_nest_start(skb, TCA_OPTIONS);
 601         if (nest == NULL)
 602                 goto nla_put_failure;
 603
 604         if (nla_put(skb, TCA_ATM_HDR, flow->hdr_len, flow->hdr))
 605                 goto nla_put_failure;
 606         if (flow->vcc) {
 607                 struct sockaddr_atmpvc pvc;
 608                 int state;
 609
 610                 memset(&pvc, 0, sizeof(pvc));
 611                 pvc.sap_family = AF_ATMPVC;
 612                 pvc.sap_addr.itf = flow->vcc->dev ? flow->vcc->dev->number : -1;
 613                 pvc.sap_addr.vpi = flow->vcc->vpi;
 614                 pvc.sap_addr.vci = flow->vcc->vci;
 615                 if (nla_put(skb, TCA_ATM_ADDR, sizeof(pvc), &pvc))
 616                         goto nla_put_failure;
 617                 state = ATM_VF2VS(flow->vcc->flags);
 618                 if (nla_put_u32(skb, TCA_ATM_STATE, state))
 619                         goto nla_put_failure;
 620         }
 621         if (flow->excess) {
 622                 if (nla_put_u32(skb, TCA_ATM_EXCESS, flow->classid))
 623                         goto nla_put_failure;
 624         } else {
 625                 if (nla_put_u32(skb, TCA_ATM_EXCESS, 0))
 626                         goto nla_put_failure;
 627         }
 628         return nla_nest_end(skb, nest);
 629
 630 nla_put_failure:
 631         nla_nest_cancel(skb, nest);
 632         return -1;
 633 }
 634 static int
 635 atm_tc_dump_class_stats(struct Qdisc *sch, unsigned long arg,
 636                         struct gnet_dump *d)
 637 {
 638         struct atm_flow_data *flow = (struct atm_flow_data *)arg;
 639
 640         if (gnet_stats_copy_basic(qdisc_root_sleeping_running(sch),
 641                                   d, NULL, &flow->bstats) < 0 ||
 642             gnet_stats_copy_queue(d, NULL, &flow->qstats, flow->q->q.qlen) < 0)
 643                 return -1;
 644
 645         return 0;
 646 }
 647
 648 static int atm_tc_dump(struct Qdisc *sch, struct sk_buff *skb)
 649 {
 650         return 0;
 651 }
 652
 653 static const struct Qdisc_class_ops atm_class_ops = {
 654         .graft          = atm_tc_graft,
 655         .leaf           = atm_tc_leaf,
 656         .get            = atm_tc_get,
 657         .put            = atm_tc_put,
 658         .change         = atm_tc_change,
 659         .delete         = atm_tc_delete,
 660         .walk           = atm_tc_walk,
 661         .tcf_block      = atm_tc_tcf_block,
 662         .bind_tcf       = atm_tc_bind_filter,
 663         .unbind_tcf     = atm_tc_put,
 664         .dump           = atm_tc_dump_class,
 665         .dump_stats     = atm_tc_dump_class_stats,
 666 };
 667
 668 static struct Qdisc_ops atm_qdisc_ops __read_mostly = {
 669         .cl_ops         = &atm_class_ops,
 670         .id             = "atm",
 671         .priv_size      = sizeof(struct atm_qdisc_data),
 672         .enqueue        = atm_tc_enqueue,
 673         .dequeue        = atm_tc_dequeue,
 674         .peek           = atm_tc_peek,
 675         .init           = atm_tc_init,
 676         .reset          = atm_tc_reset,
 677         .destroy        = atm_tc_destroy,
 678         .dump           = atm_tc_dump,
 679         .owner          = THIS_MODULE,
 680 };
 681
 682 static int __init atm_init(void)
 683 {
 684         return register_qdisc(&atm_qdisc_ops);
 685 }
 686
 687 static void __exit atm_exit(void)
 688 {
 689         unregister_qdisc(&atm_qdisc_ops);
 690 }
 691
 692 module_init(atm_init)
 693 module_exit(atm_exit)
 694 MODULE_LICENSE("GPL");