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_class_common common;
  45         struct Qdisc            *q;     /* FIFO, TBF, etc. */
  46         struct tcf_proto __rcu  *filter_list;
  47         struct tcf_block        *block;
  48         struct atm_vcc          *vcc;   /* VCC; NULL if VCC is closed */
  49         void                    (*old_pop)(struct atm_vcc *vcc,
  50                                            struct sk_buff *skb); /* chaining */
  51         struct atm_qdisc_data   *parent;        /* parent qdisc */
  52         struct socket           *sock;          /* for closing */
  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->common.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_find(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("%s(sch %p,[qdisc %p],classid %x)\n", __func__, sch, p, classid);
 117         flow = lookup_flow(sch, classid);
 118         pr_debug("%s: flow %p\n", __func__, flow);
 119         return (unsigned long)flow;
 120 }
 121
 122 static unsigned long atm_tc_bind_filter(struct Qdisc *sch,
 123                                         unsigned long parent, u32 classid)
 124 {
 125         struct atm_qdisc_data *p __maybe_unused = qdisc_priv(sch);
 126         struct atm_flow_data *flow;
 127
 128         pr_debug("%s(sch %p,[qdisc %p],classid %x)\n", __func__, sch, p, classid);
 129         flow = lookup_flow(sch, classid);
 130         if (flow)
 131                 flow->ref++;
 132         pr_debug("%s: flow %p\n", __func__, flow);
 133         return (unsigned long)flow;
 134 }
 135
 136 /*
 137  * atm_tc_put handles all destructions, including the ones that are explicitly
 138  * requested (atm_tc_destroy, etc.). The assumption here is that we never drop
 139  * anything that still seems to be in use.
 140  */
 141 static void atm_tc_put(struct Qdisc *sch, unsigned long cl)
 142 {
 143         struct atm_qdisc_data *p = qdisc_priv(sch);
 144         struct atm_flow_data *flow = (struct atm_flow_data *)cl;
 145
 146         pr_debug("atm_tc_put(sch %p,[qdisc %p],flow %p)\n", sch, p, flow);
 147         if (--flow->ref)
 148                 return;
 149         pr_debug("atm_tc_put: destroying\n");
 150         list_del_init(&flow->list);
 151         pr_debug("atm_tc_put: qdisc %p\n", flow->q);
 152         qdisc_destroy(flow->q);
 153         tcf_block_put(flow->block);
 154         if (flow->sock) {
 155                 pr_debug("atm_tc_put: f_count %ld\n",
 156                         file_count(flow->sock->file));
 157                 flow->vcc->pop = flow->old_pop;
 158                 sockfd_put(flow->sock);
 159         }
 160         if (flow->excess)
 161                 atm_tc_put(sch, (unsigned long)flow->excess);
 162         if (flow != &p->link)
 163                 kfree(flow);
 164         /*
 165          * If flow == &p->link, the qdisc no longer works at this point and
 166          * needs to be removed. (By the caller of atm_tc_put.)
 167          */
 168 }
 169
 170 static void sch_atm_pop(struct atm_vcc *vcc, struct sk_buff *skb)
 171 {
 172         struct atm_qdisc_data *p = VCC2FLOW(vcc)->parent;
 173
 174         pr_debug("sch_atm_pop(vcc %p,skb %p,[qdisc %p])\n", vcc, skb, p);
 175         VCC2FLOW(vcc)->old_pop(vcc, skb);
 176         tasklet_schedule(&p->task);
 177 }
 178
 179 static const u8 llc_oui_ip[] = {
 180         0xaa,                   /* DSAP: non-ISO */
 181         0xaa,                   /* SSAP: non-ISO */
 182         0x03,                   /* Ctrl: Unnumbered Information Command PDU */
 183         0x00,                   /* OUI: EtherType */
 184         0x00, 0x00,
 185         0x08, 0x00
 186 };                              /* Ethertype IP (0800) */
 187
 188 static const struct nla_policy atm_policy[TCA_ATM_MAX + 1] = {
 189         [TCA_ATM_FD]            = { .type = NLA_U32 },
 190         [TCA_ATM_EXCESS]        = { .type = NLA_U32 },
 191 };
 192
 193 static int atm_tc_change(struct Qdisc *sch, u32 classid, u32 parent,
 194                          struct nlattr **tca, unsigned long *arg,
 195                          struct netlink_ext_ack *extack)
 196 {
 197         struct atm_qdisc_data *p = qdisc_priv(sch);
 198         struct atm_flow_data *flow = (struct atm_flow_data *)*arg;
 199         struct atm_flow_data *excess = NULL;
 200         struct nlattr *opt = tca[TCA_OPTIONS];
 201         struct nlattr *tb[TCA_ATM_MAX + 1];
 202         struct socket *sock;
 203         int fd, error, hdr_len;
 204         void *hdr;
 205
 206         pr_debug("atm_tc_change(sch %p,[qdisc %p],classid %x,parent %x,"
 207                 "flow %p,opt %p)\n", sch, p, classid, parent, flow, opt);
 208         /*
 209          * The concept of parents doesn't apply for this qdisc.
 210          */
 211         if (parent && parent != TC_H_ROOT && parent != sch->handle)
 212                 return -EINVAL;
 213         /*
 214          * ATM classes cannot be changed. In order to change properties of the
 215          * ATM connection, that socket needs to be modified directly (via the
 216          * native ATM API. In order to send a flow to a different VC, the old
 217          * class needs to be removed and a new one added. (This may be changed
 218          * later.)
 219          */
 220         if (flow)
 221                 return -EBUSY;
 222         if (opt == NULL)
 223                 return -EINVAL;
 224
 225         error = nla_parse_nested(tb, TCA_ATM_MAX, opt, atm_policy, NULL);
 226         if (error < 0)
 227                 return error;
 228
 229         if (!tb[TCA_ATM_FD])
 230                 return -EINVAL;
 231         fd = nla_get_u32(tb[TCA_ATM_FD]);
 232         pr_debug("atm_tc_change: fd %d\n", fd);
 233         if (tb[TCA_ATM_HDR]) {
 234                 hdr_len = nla_len(tb[TCA_ATM_HDR]);
 235                 hdr = nla_data(tb[TCA_ATM_HDR]);
 236         } else {
 237                 hdr_len = RFC1483LLC_LEN;
 238                 hdr = NULL;     /* default LLC/SNAP for IP */
 239         }
 240         if (!tb[TCA_ATM_EXCESS])
 241                 excess = NULL;
 242         else {
 243                 excess = (struct atm_flow_data *)
 244                         atm_tc_find(sch, nla_get_u32(tb[TCA_ATM_EXCESS]));
 245                 if (!excess)
 246                         return -ENOENT;
 247         }
 248         pr_debug("atm_tc_change: type %d, payload %d, hdr_len %d\n",
 249                  opt->nla_type, nla_len(opt), hdr_len);
 250         sock = sockfd_lookup(fd, &error);
 251         if (!sock)
 252                 return error;   /* f_count++ */
 253         pr_debug("atm_tc_change: f_count %ld\n", file_count(sock->file));
 254         if (sock->ops->family != PF_ATMSVC && sock->ops->family != PF_ATMPVC) {
 255                 error = -EPROTOTYPE;
 256                 goto err_out;
 257         }
 258         /* @@@ should check if the socket is really operational or we'll crash
 259            on vcc->send */
 260         if (classid) {
 261                 if (TC_H_MAJ(classid ^ sch->handle)) {
 262                         pr_debug("atm_tc_change: classid mismatch\n");
 263                         error = -EINVAL;
 264                         goto err_out;
 265                 }
 266         } else {
 267                 int i;
 268                 unsigned long cl;
 269
 270                 for (i = 1; i < 0x8000; i++) {
 271                         classid = TC_H_MAKE(sch->handle, 0x8000 | i);
 272                         cl = atm_tc_find(sch, classid);
 273                         if (!cl)
 274                                 break;
 275                 }
 276         }
 277         pr_debug("atm_tc_change: new id %x\n", classid);
 278         flow = kzalloc(sizeof(struct atm_flow_data) + hdr_len, GFP_KERNEL);
 279         pr_debug("atm_tc_change: flow %p\n", flow);
 280         if (!flow) {
 281                 error = -ENOBUFS;
 282                 goto err_out;
 283         }
 284
 285         error = tcf_block_get(&flow->block, &flow->filter_list, sch);
 286         if (error) {
 287                 kfree(flow);
 288                 goto err_out;
 289         }
 290
 291         flow->q = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops, classid);
 292         if (!flow->q)
 293                 flow->q = &noop_qdisc;
 294         pr_debug("atm_tc_change: qdisc %p\n", flow->q);
 295         flow->sock = sock;
 296         flow->vcc = ATM_SD(sock);       /* speedup */
 297         flow->vcc->user_back = flow;
 298         pr_debug("atm_tc_change: vcc %p\n", flow->vcc);
 299         flow->old_pop = flow->vcc->pop;
 300         flow->parent = p;
 301         flow->vcc->pop = sch_atm_pop;
 302         flow->common.classid = classid;
 303         flow->ref = 1;
 304         flow->excess = excess;
 305         list_add(&flow->list, &p->link.list);
 306         flow->hdr_len = hdr_len;
 307         if (hdr)
 308                 memcpy(flow->hdr, hdr, hdr_len);
 309         else
 310                 memcpy(flow->hdr, llc_oui_ip, sizeof(llc_oui_ip));
 311         *arg = (unsigned long)flow;
 312         return 0;
 313 err_out:
 314         sockfd_put(sock);
 315         return error;
 316 }
 317
 318 static int atm_tc_delete(struct Qdisc *sch, unsigned long arg)
 319 {
 320         struct atm_qdisc_data *p = qdisc_priv(sch);
 321         struct atm_flow_data *flow = (struct atm_flow_data *)arg;
 322
 323         pr_debug("atm_tc_delete(sch %p,[qdisc %p],flow %p)\n", sch, p, flow);
 324         if (list_empty(&flow->list))
 325                 return -EINVAL;
 326         if (rcu_access_pointer(flow->filter_list) || flow == &p->link)
 327                 return -EBUSY;
 328         /*
 329          * Reference count must be 2: one for "keepalive" (set at class
 330          * creation), and one for the reference held when calling delete.
 331          */
 332         if (flow->ref < 2) {
 333                 pr_err("atm_tc_delete: flow->ref == %d\n", flow->ref);
 334                 return -EINVAL;
 335         }
 336         if (flow->ref > 2)
 337                 return -EBUSY;  /* catch references via excess, etc. */
 338         atm_tc_put(sch, arg);
 339         return 0;
 340 }
 341
 342 static void atm_tc_walk(struct Qdisc *sch, struct qdisc_walker *walker)
 343 {
 344         struct atm_qdisc_data *p = qdisc_priv(sch);
 345         struct atm_flow_data *flow;
 346
 347         pr_debug("atm_tc_walk(sch %p,[qdisc %p],walker %p)\n", sch, p, walker);
 348         if (walker->stop)
 349                 return;
 350         list_for_each_entry(flow, &p->flows, list) {
 351                 if (walker->count >= walker->skip &&
 352                     walker->fn(sch, (unsigned long)flow, walker) < 0) {
 353                         walker->stop = 1;
 354                         break;
 355                 }
 356                 walker->count++;
 357         }
 358 }
 359
 360 static struct tcf_block *atm_tc_tcf_block(struct Qdisc *sch, unsigned long cl)
 361 {
 362         struct atm_qdisc_data *p = qdisc_priv(sch);
 363         struct atm_flow_data *flow = (struct atm_flow_data *)cl;
 364
 365         pr_debug("atm_tc_find_tcf(sch %p,[qdisc %p],flow %p)\n", sch, p, flow);
 366         return flow ? flow->block : p->link.block;
 367 }
 368
 369 /* --------------------------- Qdisc operations ---------------------------- */
 370
 371 static int atm_tc_enqueue(struct sk_buff *skb, struct Qdisc *sch,
 372                           struct sk_buff **to_free)
 373 {
 374         struct atm_qdisc_data *p = qdisc_priv(sch);
 375         struct atm_flow_data *flow;
 376         struct tcf_result res;
 377         int result;
 378         int ret = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
 379
 380         pr_debug("atm_tc_enqueue(skb %p,sch %p,[qdisc %p])\n", skb, sch, p);
 381         result = TC_ACT_OK;     /* be nice to gcc */
 382         flow = NULL;
 383         if (TC_H_MAJ(skb->priority) != sch->handle ||
 384             !(flow = (struct atm_flow_data *)atm_tc_find(sch, skb->priority))) {
 385                 struct tcf_proto *fl;
 386
 387                 list_for_each_entry(flow, &p->flows, list) {
 388                         fl = rcu_dereference_bh(flow->filter_list);
 389                         if (fl) {
 390                                 result = tcf_classify(skb, fl, &res, true);
 391                                 if (result < 0)
 392                                         continue;
 393                                 flow = (struct atm_flow_data *)res.class;
 394                                 if (!flow)
 395                                         flow = lookup_flow(sch, res.classid);
 396                                 goto done;
 397                         }
 398                 }
 399                 flow = NULL;
 400 done:
 401                 ;
 402         }
 403         if (!flow) {
 404                 flow = &p->link;
 405         } else {
 406                 if (flow->vcc)
 407                         ATM_SKB(skb)->atm_options = flow->vcc->atm_options;
 408                 /*@@@ looks good ... but it's not supposed to work :-) */
 409 #ifdef CONFIG_NET_CLS_ACT
 410                 switch (result) {
 411                 case TC_ACT_QUEUED:
 412                 case TC_ACT_STOLEN:
 413                 case TC_ACT_TRAP:
 414                         __qdisc_drop(skb, to_free);
 415                         return NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
 416                 case TC_ACT_SHOT:
 417                         __qdisc_drop(skb, to_free);
 418                         goto drop;
 419                 case TC_ACT_RECLASSIFY:
 420                         if (flow->excess)
 421                                 flow = flow->excess;
 422                         else
 423                                 ATM_SKB(skb)->atm_options |= ATM_ATMOPT_CLP;
 424                         break;
 425                 }
 426 #endif
 427         }
 428
 429         ret = qdisc_enqueue(skb, flow->q, to_free);
 430         if (ret != NET_XMIT_SUCCESS) {
 431 drop: __maybe_unused
 432                 if (net_xmit_drop_count(ret)) {
 433                         qdisc_qstats_drop(sch);
 434                         if (flow)
 435                                 flow->qstats.drops++;
 436                 }
 437                 return ret;
 438         }
 439         /*
 440          * Okay, this may seem weird. We pretend we've dropped the packet if
 441          * it goes via ATM. The reason for this is that the outer qdisc
 442          * expects to be able to q->dequeue the packet later on if we return
 443          * success at this place. Also, sch->q.qdisc needs to reflect whether
 444          * there is a packet egligible for dequeuing or not. Note that the
 445          * statistics of the outer qdisc are necessarily wrong because of all
 446          * this. There's currently no correct solution for this.
 447          */
 448         if (flow == &p->link) {
 449                 sch->q.qlen++;
 450                 return NET_XMIT_SUCCESS;
 451         }
 452         tasklet_schedule(&p->task);
 453         return NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
 454 }
 455
 456 /*
 457  * Dequeue packets and send them over ATM. Note that we quite deliberately
 458  * avoid checking net_device's flow control here, simply because sch_atm
 459  * uses its own channels, which have nothing to do with any CLIP/LANE/or
 460  * non-ATM interfaces.
 461  */
 462
 463 static void sch_atm_dequeue(unsigned long data)
 464 {
 465         struct Qdisc *sch = (struct Qdisc *)data;
 466         struct atm_qdisc_data *p = qdisc_priv(sch);
 467         struct atm_flow_data *flow;
 468         struct sk_buff *skb;
 469
 470         pr_debug("sch_atm_dequeue(sch %p,[qdisc %p])\n", sch, p);
 471         list_for_each_entry(flow, &p->flows, list) {
 472                 if (flow == &p->link)
 473                         continue;
 474                 /*
 475                  * If traffic is properly shaped, this won't generate nasty
 476                  * little bursts. Otherwise, it may ... (but that's okay)
 477                  */
 478                 while ((skb = flow->q->ops->peek(flow->q))) {
 479                         if (!atm_may_send(flow->vcc, skb->truesize))
 480                                 break;
 481
 482                         skb = qdisc_dequeue_peeked(flow->q);
 483                         if (unlikely(!skb))
 484                                 break;
 485
 486                         qdisc_bstats_update(sch, skb);
 487                         bstats_update(&flow->bstats, skb);
 488                         pr_debug("atm_tc_dequeue: sending on class %p\n", flow);
 489                         /* remove any LL header somebody else has attached */
 490                         skb_pull(skb, skb_network_offset(skb));
 491                         if (skb_headroom(skb) < flow->hdr_len) {
 492                                 struct sk_buff *new;
 493
 494                                 new = skb_realloc_headroom(skb, flow->hdr_len);
 495                                 dev_kfree_skb(skb);
 496                                 if (!new)
 497                                         continue;
 498                                 skb = new;
 499                         }
 500                         pr_debug("sch_atm_dequeue: ip %p, data %p\n",
 501                                  skb_network_header(skb), skb->data);
 502                         ATM_SKB(skb)->vcc = flow->vcc;
 503                         memcpy(skb_push(skb, flow->hdr_len), flow->hdr,
 504                                flow->hdr_len);
 505                         refcount_add(skb->truesize,
 506                                    &sk_atm(flow->vcc)->sk_wmem_alloc);
 507                         /* atm.atm_options are already set by atm_tc_enqueue */
 508                         flow->vcc->send(flow->vcc, skb);
 509                 }
 510         }
 511 }
 512
 513 static struct sk_buff *atm_tc_dequeue(struct Qdisc *sch)
 514 {
 515         struct atm_qdisc_data *p = qdisc_priv(sch);
 516         struct sk_buff *skb;
 517
 518         pr_debug("atm_tc_dequeue(sch %p,[qdisc %p])\n", sch, p);
 519         tasklet_schedule(&p->task);
 520         skb = qdisc_dequeue_peeked(p->link.q);
 521         if (skb)
 522                 sch->q.qlen--;
 523         return skb;
 524 }
 525
 526 static struct sk_buff *atm_tc_peek(struct Qdisc *sch)
 527 {
 528         struct atm_qdisc_data *p = qdisc_priv(sch);
 529
 530         pr_debug("atm_tc_peek(sch %p,[qdisc %p])\n", sch, p);
 531
 532         return p->link.q->ops->peek(p->link.q);
 533 }
 534
 535 static int atm_tc_init(struct Qdisc *sch, struct nlattr *opt,
 536                        struct netlink_ext_ack *extack)
 537 {
 538         struct atm_qdisc_data *p = qdisc_priv(sch);
 539         int err;
 540
 541         pr_debug("atm_tc_init(sch %p,[qdisc %p],opt %p)\n", sch, p, opt);
 542         INIT_LIST_HEAD(&p->flows);
 543         INIT_LIST_HEAD(&p->link.list);
 544         list_add(&p->link.list, &p->flows);
 545         p->link.q = qdisc_create_dflt(sch->dev_queue,
 546                                       &pfifo_qdisc_ops, sch->handle);
 547         if (!p->link.q)
 548                 p->link.q = &noop_qdisc;
 549         pr_debug("atm_tc_init: link (%p) qdisc %p\n", &p->link, p->link.q);
 550
 551         err = tcf_block_get(&p->link.block, &p->link.filter_list, sch);
 552         if (err)
 553                 return err;
 554
 555         p->link.vcc = NULL;
 556         p->link.sock = NULL;
 557         p->link.common.classid = sch->handle;
 558         p->link.ref = 1;
 559         tasklet_init(&p->task, sch_atm_dequeue, (unsigned long)sch);
 560         return 0;
 561 }
 562
 563 static void atm_tc_reset(struct Qdisc *sch)
 564 {
 565         struct atm_qdisc_data *p = qdisc_priv(sch);
 566         struct atm_flow_data *flow;
 567
 568         pr_debug("atm_tc_reset(sch %p,[qdisc %p])\n", sch, p);
 569         list_for_each_entry(flow, &p->flows, list)
 570                 qdisc_reset(flow->q);
 571         sch->q.qlen = 0;
 572 }
 573
 574 static void atm_tc_destroy(struct Qdisc *sch)
 575 {
 576         struct atm_qdisc_data *p = qdisc_priv(sch);
 577         struct atm_flow_data *flow, *tmp;
 578
 579         pr_debug("atm_tc_destroy(sch %p,[qdisc %p])\n", sch, p);
 580         list_for_each_entry(flow, &p->flows, list) {
 581                 tcf_block_put(flow->block);
 582                 flow->block = NULL;
 583         }
 584
 585         list_for_each_entry_safe(flow, tmp, &p->flows, list) {
 586                 if (flow->ref > 1)
 587                         pr_err("atm_destroy: %p->ref = %d\n", flow, flow->ref);
 588                 atm_tc_put(sch, (unsigned long)flow);
 589         }
 590         tasklet_kill(&p->task);
 591 }
 592
 593 static int atm_tc_dump_class(struct Qdisc *sch, unsigned long cl,
 594                              struct sk_buff *skb, struct tcmsg *tcm)
 595 {
 596         struct atm_qdisc_data *p = qdisc_priv(sch);
 597         struct atm_flow_data *flow = (struct atm_flow_data *)cl;
 598         struct nlattr *nest;
 599
 600         pr_debug("atm_tc_dump_class(sch %p,[qdisc %p],flow %p,skb %p,tcm %p)\n",
 601                 sch, p, flow, skb, tcm);
 602         if (list_empty(&flow->list))
 603                 return -EINVAL;
 604         tcm->tcm_handle = flow->common.classid;
 605         tcm->tcm_info = flow->q->handle;
 606
 607         nest = nla_nest_start(skb, TCA_OPTIONS);
 608         if (nest == NULL)
 609                 goto nla_put_failure;
 610
 611         if (nla_put(skb, TCA_ATM_HDR, flow->hdr_len, flow->hdr))
 612                 goto nla_put_failure;
 613         if (flow->vcc) {
 614                 struct sockaddr_atmpvc pvc;
 615                 int state;
 616
 617                 memset(&pvc, 0, sizeof(pvc));
 618                 pvc.sap_family = AF_ATMPVC;
 619                 pvc.sap_addr.itf = flow->vcc->dev ? flow->vcc->dev->number : -1;
 620                 pvc.sap_addr.vpi = flow->vcc->vpi;
 621                 pvc.sap_addr.vci = flow->vcc->vci;
 622                 if (nla_put(skb, TCA_ATM_ADDR, sizeof(pvc), &pvc))
 623                         goto nla_put_failure;
 624                 state = ATM_VF2VS(flow->vcc->flags);
 625                 if (nla_put_u32(skb, TCA_ATM_STATE, state))
 626                         goto nla_put_failure;
 627         }
 628         if (flow->excess) {
 629                 if (nla_put_u32(skb, TCA_ATM_EXCESS, flow->common.classid))
 630                         goto nla_put_failure;
 631         } else {
 632                 if (nla_put_u32(skb, TCA_ATM_EXCESS, 0))
 633                         goto nla_put_failure;
 634         }
 635         return nla_nest_end(skb, nest);
 636
 637 nla_put_failure:
 638         nla_nest_cancel(skb, nest);
 639         return -1;
 640 }
 641 static int
 642 atm_tc_dump_class_stats(struct Qdisc *sch, unsigned long arg,
 643                         struct gnet_dump *d)
 644 {
 645         struct atm_flow_data *flow = (struct atm_flow_data *)arg;
 646
 647         if (gnet_stats_copy_basic(qdisc_root_sleeping_running(sch),
 648                                   d, NULL, &flow->bstats) < 0 ||
 649             gnet_stats_copy_queue(d, NULL, &flow->qstats, flow->q->q.qlen) < 0)
 650                 return -1;
 651
 652         return 0;
 653 }
 654
 655 static int atm_tc_dump(struct Qdisc *sch, struct sk_buff *skb)
 656 {
 657         return 0;
 658 }
 659
 660 static const struct Qdisc_class_ops atm_class_ops = {
 661         .graft          = atm_tc_graft,
 662         .leaf           = atm_tc_leaf,
 663         .find           = atm_tc_find,
 664         .change         = atm_tc_change,
 665         .delete         = atm_tc_delete,
 666         .walk           = atm_tc_walk,
 667         .tcf_block      = atm_tc_tcf_block,
 668         .bind_tcf       = atm_tc_bind_filter,
 669         .unbind_tcf     = atm_tc_put,
 670         .dump           = atm_tc_dump_class,
 671         .dump_stats     = atm_tc_dump_class_stats,
 672 };
 673
 674 static struct Qdisc_ops atm_qdisc_ops __read_mostly = {
 675         .cl_ops         = &atm_class_ops,
 676         .id             = "atm",
 677         .priv_size      = sizeof(struct atm_qdisc_data),
 678         .enqueue        = atm_tc_enqueue,
 679         .dequeue        = atm_tc_dequeue,
 680         .peek           = atm_tc_peek,
 681         .init           = atm_tc_init,
 682         .reset          = atm_tc_reset,
 683         .destroy        = atm_tc_destroy,
 684         .dump           = atm_tc_dump,
 685         .owner          = THIS_MODULE,
 686 };
 687
 688 static int __init atm_init(void)
 689 {
 690         return register_qdisc(&atm_qdisc_ops);
 691 }
 692
 693 static void __exit atm_exit(void)
 694 {
 695         unregister_qdisc(&atm_qdisc_ops);
 696 }
 697
 698 module_init(atm_init)
 699 module_exit(atm_exit)
 700 MODULE_LICENSE("GPL");