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                         struct netlink_ext_ack *extack)
  87 {
  88         struct atm_qdisc_data *p = qdisc_priv(sch);
  89         struct atm_flow_data *flow = (struct atm_flow_data *)arg;
  90
  91         pr_debug("atm_tc_graft(sch %p,[qdisc %p],flow %p,new %p,old %p)\n",
  92                 sch, p, flow, new, old);
  93         if (list_empty(&flow->list))
  94                 return -EINVAL;
  95         if (!new)
  96                 new = &noop_qdisc;
  97         *old = flow->q;
  98         flow->q = new;
  99         if (*old)
 100                 qdisc_reset(*old);
 101         return 0;
 102 }
 103
 104 static struct Qdisc *atm_tc_leaf(struct Qdisc *sch, unsigned long cl)
 105 {
 106         struct atm_flow_data *flow = (struct atm_flow_data *)cl;
 107
 108         pr_debug("atm_tc_leaf(sch %p,flow %p)\n", sch, flow);
 109         return flow ? flow->q : NULL;
 110 }
 111
 112 static unsigned long atm_tc_find(struct Qdisc *sch, u32 classid)
 113 {
 114         struct atm_qdisc_data *p __maybe_unused = qdisc_priv(sch);
 115         struct atm_flow_data *flow;
 116
 117         pr_debug("%s(sch %p,[qdisc %p],classid %x)\n", __func__, sch, p, classid);
 118         flow = lookup_flow(sch, classid);
 119         pr_debug("%s: flow %p\n", __func__, flow);
 120         return (unsigned long)flow;
 121 }
 122
 123 static unsigned long atm_tc_bind_filter(struct Qdisc *sch,
 124                                         unsigned long parent, u32 classid)
 125 {
 126         struct atm_qdisc_data *p __maybe_unused = qdisc_priv(sch);
 127         struct atm_flow_data *flow;
 128
 129         pr_debug("%s(sch %p,[qdisc %p],classid %x)\n", __func__, sch, p, classid);
 130         flow = lookup_flow(sch, classid);
 131         if (flow)
 132                 flow->ref++;
 133         pr_debug("%s: flow %p\n", __func__, flow);
 134         return (unsigned long)flow;
 135 }
 136
 137 /*
 138  * atm_tc_put handles all destructions, including the ones that are explicitly
 139  * requested (atm_tc_destroy, etc.). The assumption here is that we never drop
 140  * anything that still seems to be in use.
 141  */
 142 static void atm_tc_put(struct Qdisc *sch, unsigned long cl)
 143 {
 144         struct atm_qdisc_data *p = qdisc_priv(sch);
 145         struct atm_flow_data *flow = (struct atm_flow_data *)cl;
 146
 147         pr_debug("atm_tc_put(sch %p,[qdisc %p],flow %p)\n", sch, p, flow);
 148         if (--flow->ref)
 149                 return;
 150         pr_debug("atm_tc_put: destroying\n");
 151         list_del_init(&flow->list);
 152         pr_debug("atm_tc_put: qdisc %p\n", flow->q);
 153         qdisc_put(flow->q);
 154         tcf_block_put(flow->block);
 155         if (flow->sock) {
 156                 pr_debug("atm_tc_put: f_count %ld\n",
 157                         file_count(flow->sock->file));
 158                 flow->vcc->pop = flow->old_pop;
 159                 sockfd_put(flow->sock);
 160         }
 161         if (flow->excess)
 162                 atm_tc_put(sch, (unsigned long)flow->excess);
 163         if (flow != &p->link)
 164                 kfree(flow);
 165         /*
 166          * If flow == &p->link, the qdisc no longer works at this point and
 167          * needs to be removed. (By the caller of atm_tc_put.)
 168          */
 169 }
 170
 171 static void sch_atm_pop(struct atm_vcc *vcc, struct sk_buff *skb)
 172 {
 173         struct atm_qdisc_data *p = VCC2FLOW(vcc)->parent;
 174
 175         pr_debug("sch_atm_pop(vcc %p,skb %p,[qdisc %p])\n", vcc, skb, p);
 176         VCC2FLOW(vcc)->old_pop(vcc, skb);
 177         tasklet_schedule(&p->task);
 178 }
 179
 180 static const u8 llc_oui_ip[] = {
 181         0xaa,                   /* DSAP: non-ISO */
 182         0xaa,                   /* SSAP: non-ISO */
 183         0x03,                   /* Ctrl: Unnumbered Information Command PDU */
 184         0x00,                   /* OUI: EtherType */
 185         0x00, 0x00,
 186         0x08, 0x00
 187 };                              /* Ethertype IP (0800) */
 188
 189 static const struct nla_policy atm_policy[TCA_ATM_MAX + 1] = {
 190         [TCA_ATM_FD]            = { .type = NLA_U32 },
 191         [TCA_ATM_EXCESS]        = { .type = NLA_U32 },
 192 };
 193
 194 static int atm_tc_change(struct Qdisc *sch, u32 classid, u32 parent,
 195                          struct nlattr **tca, unsigned long *arg,
 196                          struct netlink_ext_ack *extack)
 197 {
 198         struct atm_qdisc_data *p = qdisc_priv(sch);
 199         struct atm_flow_data *flow = (struct atm_flow_data *)*arg;
 200         struct atm_flow_data *excess = NULL;
 201         struct nlattr *opt = tca[TCA_OPTIONS];
 202         struct nlattr *tb[TCA_ATM_MAX + 1];
 203         struct socket *sock;
 204         int fd, error, hdr_len;
 205         void *hdr;
 206
 207         pr_debug("atm_tc_change(sch %p,[qdisc %p],classid %x,parent %x,"
 208                 "flow %p,opt %p)\n", sch, p, classid, parent, flow, opt);
 209         /*
 210          * The concept of parents doesn't apply for this qdisc.
 211          */
 212         if (parent && parent != TC_H_ROOT && parent != sch->handle)
 213                 return -EINVAL;
 214         /*
 215          * ATM classes cannot be changed. In order to change properties of the
 216          * ATM connection, that socket needs to be modified directly (via the
 217          * native ATM API. In order to send a flow to a different VC, the old
 218          * class needs to be removed and a new one added. (This may be changed
 219          * later.)
 220          */
 221         if (flow)
 222                 return -EBUSY;
 223         if (opt == NULL)
 224                 return -EINVAL;
 225
 226         error = nla_parse_nested_deprecated(tb, TCA_ATM_MAX, opt, atm_policy,
 227                                             NULL);
 228         if (error < 0)
 229                 return error;
 230
 231         if (!tb[TCA_ATM_FD])
 232                 return -EINVAL;
 233         fd = nla_get_u32(tb[TCA_ATM_FD]);
 234         pr_debug("atm_tc_change: fd %d\n", fd);
 235         if (tb[TCA_ATM_HDR]) {
 236                 hdr_len = nla_len(tb[TCA_ATM_HDR]);
 237                 hdr = nla_data(tb[TCA_ATM_HDR]);
 238         } else {
 239                 hdr_len = RFC1483LLC_LEN;
 240                 hdr = NULL;     /* default LLC/SNAP for IP */
 241         }
 242         if (!tb[TCA_ATM_EXCESS])
 243                 excess = NULL;
 244         else {
 245                 excess = (struct atm_flow_data *)
 246                         atm_tc_find(sch, nla_get_u32(tb[TCA_ATM_EXCESS]));
 247                 if (!excess)
 248                         return -ENOENT;
 249         }
 250         pr_debug("atm_tc_change: type %d, payload %d, hdr_len %d\n",
 251                  opt->nla_type, nla_len(opt), hdr_len);
 252         sock = sockfd_lookup(fd, &error);
 253         if (!sock)
 254                 return error;   /* f_count++ */
 255         pr_debug("atm_tc_change: f_count %ld\n", file_count(sock->file));
 256         if (sock->ops->family != PF_ATMSVC && sock->ops->family != PF_ATMPVC) {
 257                 error = -EPROTOTYPE;
 258                 goto err_out;
 259         }
 260         /* @@@ should check if the socket is really operational or we'll crash
 261            on vcc->send */
 262         if (classid) {
 263                 if (TC_H_MAJ(classid ^ sch->handle)) {
 264                         pr_debug("atm_tc_change: classid mismatch\n");
 265                         error = -EINVAL;
 266                         goto err_out;
 267                 }
 268         } else {
 269                 int i;
 270                 unsigned long cl;
 271
 272                 for (i = 1; i < 0x8000; i++) {
 273                         classid = TC_H_MAKE(sch->handle, 0x8000 | i);
 274                         cl = atm_tc_find(sch, classid);
 275                         if (!cl)
 276                                 break;
 277                 }
 278         }
 279         pr_debug("atm_tc_change: new id %x\n", classid);
 280         flow = kzalloc(sizeof(struct atm_flow_data) + hdr_len, GFP_KERNEL);
 281         pr_debug("atm_tc_change: flow %p\n", flow);
 282         if (!flow) {
 283                 error = -ENOBUFS;
 284                 goto err_out;
 285         }
 286
 287         error = tcf_block_get(&flow->block, &flow->filter_list, sch,
 288                               extack);
 289         if (error) {
 290                 kfree(flow);
 291                 goto err_out;
 292         }
 293
 294         flow->q = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops, classid,
 295                                     extack);
 296         if (!flow->q)
 297                 flow->q = &noop_qdisc;
 298         pr_debug("atm_tc_change: qdisc %p\n", flow->q);
 299         flow->sock = sock;
 300         flow->vcc = ATM_SD(sock);       /* speedup */
 301         flow->vcc->user_back = flow;
 302         pr_debug("atm_tc_change: vcc %p\n", flow->vcc);
 303         flow->old_pop = flow->vcc->pop;
 304         flow->parent = p;
 305         flow->vcc->pop = sch_atm_pop;
 306         flow->common.classid = classid;
 307         flow->ref = 1;
 308         flow->excess = excess;
 309         list_add(&flow->list, &p->link.list);
 310         flow->hdr_len = hdr_len;
 311         if (hdr)
 312                 memcpy(flow->hdr, hdr, hdr_len);
 313         else
 314                 memcpy(flow->hdr, llc_oui_ip, sizeof(llc_oui_ip));
 315         *arg = (unsigned long)flow;
 316         return 0;
 317 err_out:
 318         sockfd_put(sock);
 319         return error;
 320 }
 321
 322 static int atm_tc_delete(struct Qdisc *sch, unsigned long arg)
 323 {
 324         struct atm_qdisc_data *p = qdisc_priv(sch);
 325         struct atm_flow_data *flow = (struct atm_flow_data *)arg;
 326
 327         pr_debug("atm_tc_delete(sch %p,[qdisc %p],flow %p)\n", sch, p, flow);
 328         if (list_empty(&flow->list))
 329                 return -EINVAL;
 330         if (rcu_access_pointer(flow->filter_list) || flow == &p->link)
 331                 return -EBUSY;
 332         /*
 333          * Reference count must be 2: one for "keepalive" (set at class
 334          * creation), and one for the reference held when calling delete.
 335          */
 336         if (flow->ref < 2) {
 337                 pr_err("atm_tc_delete: flow->ref == %d\n", flow->ref);
 338                 return -EINVAL;
 339         }
 340         if (flow->ref > 2)
 341                 return -EBUSY;  /* catch references via excess, etc. */
 342         atm_tc_put(sch, arg);
 343         return 0;
 344 }
 345
 346 static void atm_tc_walk(struct Qdisc *sch, struct qdisc_walker *walker)
 347 {
 348         struct atm_qdisc_data *p = qdisc_priv(sch);
 349         struct atm_flow_data *flow;
 350
 351         pr_debug("atm_tc_walk(sch %p,[qdisc %p],walker %p)\n", sch, p, walker);
 352         if (walker->stop)
 353                 return;
 354         list_for_each_entry(flow, &p->flows, list) {
 355                 if (walker->count >= walker->skip &&
 356                     walker->fn(sch, (unsigned long)flow, walker) < 0) {
 357                         walker->stop = 1;
 358                         break;
 359                 }
 360                 walker->count++;
 361         }
 362 }
 363
 364 static struct tcf_block *atm_tc_tcf_block(struct Qdisc *sch, unsigned long cl,
 365                                           struct netlink_ext_ack *extack)
 366 {
 367         struct atm_qdisc_data *p = qdisc_priv(sch);
 368         struct atm_flow_data *flow = (struct atm_flow_data *)cl;
 369
 370         pr_debug("atm_tc_find_tcf(sch %p,[qdisc %p],flow %p)\n", sch, p, flow);
 371         return flow ? flow->block : p->link.block;
 372 }
 373
 374 /* --------------------------- Qdisc operations ---------------------------- */
 375
 376 static int atm_tc_enqueue(struct sk_buff *skb, struct Qdisc *sch,
 377                           struct sk_buff **to_free)
 378 {
 379         struct atm_qdisc_data *p = qdisc_priv(sch);
 380         struct atm_flow_data *flow;
 381         struct tcf_result res;
 382         int result;
 383         int ret = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
 384
 385         pr_debug("atm_tc_enqueue(skb %p,sch %p,[qdisc %p])\n", skb, sch, p);
 386         result = TC_ACT_OK;     /* be nice to gcc */
 387         flow = NULL;
 388         if (TC_H_MAJ(skb->priority) != sch->handle ||
 389             !(flow = (struct atm_flow_data *)atm_tc_find(sch, skb->priority))) {
 390                 struct tcf_proto *fl;
 391
 392                 list_for_each_entry(flow, &p->flows, list) {
 393                         fl = rcu_dereference_bh(flow->filter_list);
 394                         if (fl) {
 395                                 result = tcf_classify(skb, fl, &res, true);
 396                                 if (result < 0)
 397                                         continue;
 398                                 flow = (struct atm_flow_data *)res.class;
 399                                 if (!flow)
 400                                         flow = lookup_flow(sch, res.classid);
 401                                 goto done;
 402                         }
 403                 }
 404                 flow = NULL;
 405 done:
 406                 ;
 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                 case TC_ACT_TRAP:
 419                         __qdisc_drop(skb, to_free);
 420                         return NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
 421                 case TC_ACT_SHOT:
 422                         __qdisc_drop(skb, to_free);
 423                         goto drop;
 424                 case TC_ACT_RECLASSIFY:
 425                         if (flow->excess)
 426                                 flow = flow->excess;
 427                         else
 428                                 ATM_SKB(skb)->atm_options |= ATM_ATMOPT_CLP;
 429                         break;
 430                 }
 431 #endif
 432         }
 433
 434         ret = qdisc_enqueue(skb, flow->q, to_free);
 435         if (ret != NET_XMIT_SUCCESS) {
 436 drop: __maybe_unused
 437                 if (net_xmit_drop_count(ret)) {
 438                         qdisc_qstats_drop(sch);
 439                         if (flow)
 440                                 flow->qstats.drops++;
 441                 }
 442                 return ret;
 443         }
 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 NET_XMIT_SUCCESS;
 456         }
 457         tasklet_schedule(&p->task);
 458         return NET_XMIT_SUCCESS | __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 = qdisc_priv(sch);
 472         struct atm_flow_data *flow;
 473         struct sk_buff *skb;
 474
 475         pr_debug("sch_atm_dequeue(sch %p,[qdisc %p])\n", sch, p);
 476         list_for_each_entry(flow, &p->flows, list) {
 477                 if (flow == &p->link)
 478                         continue;
 479                 /*
 480                  * If traffic is properly shaped, this won't generate nasty
 481                  * little bursts. Otherwise, it may ... (but that's okay)
 482                  */
 483                 while ((skb = flow->q->ops->peek(flow->q))) {
 484                         if (!atm_may_send(flow->vcc, skb->truesize))
 485                                 break;
 486
 487                         skb = qdisc_dequeue_peeked(flow->q);
 488                         if (unlikely(!skb))
 489                                 break;
 490
 491                         qdisc_bstats_update(sch, skb);
 492                         bstats_update(&flow->bstats, skb);
 493                         pr_debug("atm_tc_dequeue: sending on class %p\n", flow);
 494                         /* remove any LL header somebody else has attached */
 495                         skb_pull(skb, skb_network_offset(skb));
 496                         if (skb_headroom(skb) < flow->hdr_len) {
 497                                 struct sk_buff *new;
 498
 499                                 new = skb_realloc_headroom(skb, flow->hdr_len);
 500                                 dev_kfree_skb(skb);
 501                                 if (!new)
 502                                         continue;
 503                                 skb = new;
 504                         }
 505                         pr_debug("sch_atm_dequeue: ip %p, data %p\n",
 506                                  skb_network_header(skb), skb->data);
 507                         ATM_SKB(skb)->vcc = flow->vcc;
 508                         memcpy(skb_push(skb, flow->hdr_len), flow->hdr,
 509                                flow->hdr_len);
 510                         refcount_add(skb->truesize,
 511                                    &sk_atm(flow->vcc)->sk_wmem_alloc);
 512                         /* atm.atm_options are already set by atm_tc_enqueue */
 513                         flow->vcc->send(flow->vcc, skb);
 514                 }
 515         }
 516 }
 517
 518 static struct sk_buff *atm_tc_dequeue(struct Qdisc *sch)
 519 {
 520         struct atm_qdisc_data *p = qdisc_priv(sch);
 521         struct sk_buff *skb;
 522
 523         pr_debug("atm_tc_dequeue(sch %p,[qdisc %p])\n", sch, p);
 524         tasklet_schedule(&p->task);
 525         skb = qdisc_dequeue_peeked(p->link.q);
 526         if (skb)
 527                 sch->q.qlen--;
 528         return skb;
 529 }
 530
 531 static struct sk_buff *atm_tc_peek(struct Qdisc *sch)
 532 {
 533         struct atm_qdisc_data *p = qdisc_priv(sch);
 534
 535         pr_debug("atm_tc_peek(sch %p,[qdisc %p])\n", sch, p);
 536
 537         return p->link.q->ops->peek(p->link.q);
 538 }
 539
 540 static int atm_tc_init(struct Qdisc *sch, struct nlattr *opt,
 541                        struct netlink_ext_ack *extack)
 542 {
 543         struct atm_qdisc_data *p = qdisc_priv(sch);
 544         int err;
 545
 546         pr_debug("atm_tc_init(sch %p,[qdisc %p],opt %p)\n", sch, p, opt);
 547         INIT_LIST_HEAD(&p->flows);
 548         INIT_LIST_HEAD(&p->link.list);
 549         list_add(&p->link.list, &p->flows);
 550         p->link.q = qdisc_create_dflt(sch->dev_queue,
 551                                       &pfifo_qdisc_ops, sch->handle, extack);
 552         if (!p->link.q)
 553                 p->link.q = &noop_qdisc;
 554         pr_debug("atm_tc_init: link (%p) qdisc %p\n", &p->link, p->link.q);
 555
 556         err = tcf_block_get(&p->link.block, &p->link.filter_list, sch,
 557                             extack);
 558         if (err)
 559                 return err;
 560
 561         p->link.vcc = NULL;
 562         p->link.sock = NULL;
 563         p->link.common.classid = sch->handle;
 564         p->link.ref = 1;
 565         tasklet_init(&p->task, sch_atm_dequeue, (unsigned long)sch);
 566         return 0;
 567 }
 568
 569 static void atm_tc_reset(struct Qdisc *sch)
 570 {
 571         struct atm_qdisc_data *p = qdisc_priv(sch);
 572         struct atm_flow_data *flow;
 573
 574         pr_debug("atm_tc_reset(sch %p,[qdisc %p])\n", sch, p);
 575         list_for_each_entry(flow, &p->flows, list)
 576                 qdisc_reset(flow->q);
 577         sch->q.qlen = 0;
 578 }
 579
 580 static void atm_tc_destroy(struct Qdisc *sch)
 581 {
 582         struct atm_qdisc_data *p = qdisc_priv(sch);
 583         struct atm_flow_data *flow, *tmp;
 584
 585         pr_debug("atm_tc_destroy(sch %p,[qdisc %p])\n", sch, p);
 586         list_for_each_entry(flow, &p->flows, list) {
 587                 tcf_block_put(flow->block);
 588                 flow->block = NULL;
 589         }
 590
 591         list_for_each_entry_safe(flow, tmp, &p->flows, list) {
 592                 if (flow->ref > 1)
 593                         pr_err("atm_destroy: %p->ref = %d\n", flow, flow->ref);
 594                 atm_tc_put(sch, (unsigned long)flow);
 595         }
 596         tasklet_kill(&p->task);
 597 }
 598
 599 static int atm_tc_dump_class(struct Qdisc *sch, unsigned long cl,
 600                              struct sk_buff *skb, struct tcmsg *tcm)
 601 {
 602         struct atm_qdisc_data *p = qdisc_priv(sch);
 603         struct atm_flow_data *flow = (struct atm_flow_data *)cl;
 604         struct nlattr *nest;
 605
 606         pr_debug("atm_tc_dump_class(sch %p,[qdisc %p],flow %p,skb %p,tcm %p)\n",
 607                 sch, p, flow, skb, tcm);
 608         if (list_empty(&flow->list))
 609                 return -EINVAL;
 610         tcm->tcm_handle = flow->common.classid;
 611         tcm->tcm_info = flow->q->handle;
 612
 613         nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
 614         if (nest == NULL)
 615                 goto nla_put_failure;
 616
 617         if (nla_put(skb, TCA_ATM_HDR, flow->hdr_len, flow->hdr))
 618                 goto nla_put_failure;
 619         if (flow->vcc) {
 620                 struct sockaddr_atmpvc pvc;
 621                 int state;
 622
 623                 memset(&pvc, 0, sizeof(pvc));
 624                 pvc.sap_family = AF_ATMPVC;
 625                 pvc.sap_addr.itf = flow->vcc->dev ? flow->vcc->dev->number : -1;
 626                 pvc.sap_addr.vpi = flow->vcc->vpi;
 627                 pvc.sap_addr.vci = flow->vcc->vci;
 628                 if (nla_put(skb, TCA_ATM_ADDR, sizeof(pvc), &pvc))
 629                         goto nla_put_failure;
 630                 state = ATM_VF2VS(flow->vcc->flags);
 631                 if (nla_put_u32(skb, TCA_ATM_STATE, state))
 632                         goto nla_put_failure;
 633         }
 634         if (flow->excess) {
 635                 if (nla_put_u32(skb, TCA_ATM_EXCESS, flow->common.classid))
 636                         goto nla_put_failure;
 637         } else {
 638                 if (nla_put_u32(skb, TCA_ATM_EXCESS, 0))
 639                         goto nla_put_failure;
 640         }
 641         return nla_nest_end(skb, nest);
 642
 643 nla_put_failure:
 644         nla_nest_cancel(skb, nest);
 645         return -1;
 646 }
 647 static int
 648 atm_tc_dump_class_stats(struct Qdisc *sch, unsigned long arg,
 649                         struct gnet_dump *d)
 650 {
 651         struct atm_flow_data *flow = (struct atm_flow_data *)arg;
 652
 653         if (gnet_stats_copy_basic(qdisc_root_sleeping_running(sch),
 654                                   d, NULL, &flow->bstats) < 0 ||
 655             gnet_stats_copy_queue(d, NULL, &flow->qstats, flow->q->q.qlen) < 0)
 656                 return -1;
 657
 658         return 0;
 659 }
 660
 661 static int atm_tc_dump(struct Qdisc *sch, struct sk_buff *skb)
 662 {
 663         return 0;
 664 }
 665
 666 static const struct Qdisc_class_ops atm_class_ops = {
 667         .graft          = atm_tc_graft,
 668         .leaf           = atm_tc_leaf,
 669         .find           = atm_tc_find,
 670         .change         = atm_tc_change,
 671         .delete         = atm_tc_delete,
 672         .walk           = atm_tc_walk,
 673         .tcf_block      = atm_tc_tcf_block,
 674         .bind_tcf       = atm_tc_bind_filter,
 675         .unbind_tcf     = atm_tc_put,
 676         .dump           = atm_tc_dump_class,
 677         .dump_stats     = atm_tc_dump_class_stats,
 678 };
 679
 680 static struct Qdisc_ops atm_qdisc_ops __read_mostly = {
 681         .cl_ops         = &atm_class_ops,
 682         .id             = "atm",
 683         .priv_size      = sizeof(struct atm_qdisc_data),
 684         .enqueue        = atm_tc_enqueue,
 685         .dequeue        = atm_tc_dequeue,
 686         .peek           = atm_tc_peek,
 687         .init           = atm_tc_init,
 688         .reset          = atm_tc_reset,
 689         .destroy        = atm_tc_destroy,
 690         .dump           = atm_tc_dump,
 691         .owner          = THIS_MODULE,
 692 };
 693
 694 static int __init atm_init(void)
 695 {
 696         return register_qdisc(&atm_qdisc_ops);
 697 }
 698
 699 static void __exit atm_exit(void)
 700 {
 701         unregister_qdisc(&atm_qdisc_ops);
 702 }
 703
 704 module_init(atm_init)
 705 module_exit(atm_exit)
 706 MODULE_LICENSE("GPL");