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 /*
  20  * The ATM queuing discipline provides a framework for invoking classifiers
  21  * (aka "filters"), which in turn select classes of this queuing discipline.
  22  * Each class maps the flow(s) it is handling to a given VC. Multiple classes
  23  * may share the same VC.
  24  *
  25  * When creating a class, VCs are specified by passing the number of the open
  26  * socket descriptor by which the calling process references the VC. The kernel
  27  * keeps the VC open at least until all classes using it are removed.
  28  *
  29  * In this file, most functions are named atm_tc_* to avoid confusion with all
  30  * the atm_* in net/atm. This naming convention differs from what's used in the
  31  * rest of net/sched.
  32  *
  33  * Known bugs:
  34  *  - sometimes messes up the IP stack
  35  *  - any manipulations besides the few operations described in the README, are
  36  *    untested and likely to crash the system
  37  *  - should lock the flow while there is data in the queue (?)
  38  */
  39
  40 #define VCC2FLOW(vcc) ((struct atm_flow_data *) ((vcc)->user_back))
  41
  42 struct atm_flow_data {
  43         struct Qdisc            *q;     /* FIFO, TBF, etc. */
  44         struct tcf_proto        *filter_list;
  45         struct atm_vcc          *vcc;   /* VCC; NULL if VCC is closed */
  46         void                    (*old_pop)(struct atm_vcc *vcc,
  47                                            struct sk_buff *skb); /* chaining */
  48         struct atm_qdisc_data   *parent;        /* parent qdisc */
  49         struct socket           *sock;          /* for closing */
  50         u32                     classid;        /* x:y type ID */
  51         int                     ref;            /* reference count */
  52         struct gnet_stats_basic_packed  bstats;
  53         struct gnet_stats_queue qstats;
  54         struct atm_flow_data    *next;
  55         struct atm_flow_data    *excess;        /* flow for excess traffic;
  56                                                    NULL to set CLP instead */
  57         int                     hdr_len;
  58         unsigned char           hdr[0];         /* header data; MUST BE LAST */
  59 };
  60
  61 struct atm_qdisc_data {
  62         struct atm_flow_data    link;           /* unclassified skbs go here */
  63         struct atm_flow_data    *flows;         /* NB: "link" is also on this
  64                                                    list */
  65         struct tasklet_struct   task;           /* dequeue tasklet */
  66 };
  67
  68 /* ------------------------- Class/flow operations ------------------------- */
  69
  70 static int find_flow(struct atm_qdisc_data *qdisc, struct atm_flow_data *flow)
  71 {
  72         struct atm_flow_data *walk;
  73
  74         pr_debug("find_flow(qdisc %p,flow %p)\n", qdisc, flow);
  75         for (walk = qdisc->flows; walk; walk = walk->next)
  76                 if (walk == flow)
  77                         return 1;
  78         pr_debug("find_flow: not found\n");
  79         return 0;
  80 }
  81
  82 static inline struct atm_flow_data *lookup_flow(struct Qdisc *sch, u32 classid)
  83 {
  84         struct atm_qdisc_data *p = qdisc_priv(sch);
  85         struct atm_flow_data *flow;
  86
  87         for (flow = p->flows; flow; flow = flow->next)
  88                 if (flow->classid == classid)
  89                         break;
  90         return flow;
  91 }
  92
  93 static int atm_tc_graft(struct Qdisc *sch, unsigned long arg,
  94                         struct Qdisc *new, struct Qdisc **old)
  95 {
  96         struct atm_qdisc_data *p = qdisc_priv(sch);
  97         struct atm_flow_data *flow = (struct atm_flow_data *)arg;
  98
  99         pr_debug("atm_tc_graft(sch %p,[qdisc %p],flow %p,new %p,old %p)\n",
 100                 sch, p, flow, new, old);
 101         if (!find_flow(p, flow))
 102                 return -EINVAL;
 103         if (!new)
 104                 new = &noop_qdisc;
 105         *old = flow->q;
 106         flow->q = new;
 107         if (*old)
 108                 qdisc_reset(*old);
 109         return 0;
 110 }
 111
 112 static struct Qdisc *atm_tc_leaf(struct Qdisc *sch, unsigned long cl)
 113 {
 114         struct atm_flow_data *flow = (struct atm_flow_data *)cl;
 115
 116         pr_debug("atm_tc_leaf(sch %p,flow %p)\n", sch, flow);
 117         return flow ? flow->q : NULL;
 118 }
 119
 120 static unsigned long atm_tc_get(struct Qdisc *sch, u32 classid)
 121 {
 122         struct atm_qdisc_data *p __maybe_unused = qdisc_priv(sch);
 123         struct atm_flow_data *flow;
 124
 125         pr_debug("atm_tc_get(sch %p,[qdisc %p],classid %x)\n", sch, p, classid);
 126         flow = lookup_flow(sch, classid);
 127         if (flow)
 128                 flow->ref++;
 129         pr_debug("atm_tc_get: flow %p\n", flow);
 130         return (unsigned long)flow;
 131 }
 132
 133 static unsigned long atm_tc_bind_filter(struct Qdisc *sch,
 134                                         unsigned long parent, u32 classid)
 135 {
 136         return atm_tc_get(sch, classid);
 137 }
 138
 139 /*
 140  * atm_tc_put handles all destructions, including the ones that are explicitly
 141  * requested (atm_tc_destroy, etc.). The assumption here is that we never drop
 142  * anything that still seems to be in use.
 143  */
 144 static void atm_tc_put(struct Qdisc *sch, unsigned long cl)
 145 {
 146         struct atm_qdisc_data *p = qdisc_priv(sch);
 147         struct atm_flow_data *flow = (struct atm_flow_data *)cl;
 148         struct atm_flow_data **prev;
 149
 150         pr_debug("atm_tc_put(sch %p,[qdisc %p],flow %p)\n", sch, p, flow);
 151         if (--flow->ref)
 152                 return;
 153         pr_debug("atm_tc_put: destroying\n");
 154         for (prev = &p->flows; *prev; prev = &(*prev)->next)
 155                 if (*prev == flow)
 156                         break;
 157         if (!*prev) {
 158                 printk(KERN_CRIT "atm_tc_put: class %p not found\n", flow);
 159                 return;
 160         }
 161         *prev = flow->next;
 162         pr_debug("atm_tc_put: qdisc %p\n", flow->q);
 163         qdisc_destroy(flow->q);
 164         tcf_destroy_chain(&flow->filter_list);
 165         if (flow->sock) {
 166                 pr_debug("atm_tc_put: f_count %ld\n",
 167                         file_count(flow->sock->file));
 168                 flow->vcc->pop = flow->old_pop;
 169                 sockfd_put(flow->sock);
 170         }
 171         if (flow->excess)
 172                 atm_tc_put(sch, (unsigned long)flow->excess);
 173         if (flow != &p->link)
 174                 kfree(flow);
 175         /*
 176          * If flow == &p->link, the qdisc no longer works at this point and
 177          * needs to be removed. (By the caller of atm_tc_put.)
 178          */
 179 }
 180
 181 static void sch_atm_pop(struct atm_vcc *vcc, struct sk_buff *skb)
 182 {
 183         struct atm_qdisc_data *p = VCC2FLOW(vcc)->parent;
 184
 185         pr_debug("sch_atm_pop(vcc %p,skb %p,[qdisc %p])\n", vcc, skb, p);
 186         VCC2FLOW(vcc)->old_pop(vcc, skb);
 187         tasklet_schedule(&p->task);
 188 }
 189
 190 static const u8 llc_oui_ip[] = {
 191         0xaa,                   /* DSAP: non-ISO */
 192         0xaa,                   /* SSAP: non-ISO */
 193         0x03,                   /* Ctrl: Unnumbered Information Command PDU */
 194         0x00,                   /* OUI: EtherType */
 195         0x00, 0x00,
 196         0x08, 0x00
 197 };                              /* Ethertype IP (0800) */
 198
 199 static const struct nla_policy atm_policy[TCA_ATM_MAX + 1] = {
 200         [TCA_ATM_FD]            = { .type = NLA_U32 },
 201         [TCA_ATM_EXCESS]        = { .type = NLA_U32 },
 202 };
 203
 204 static int atm_tc_change(struct Qdisc *sch, u32 classid, u32 parent,
 205                          struct nlattr **tca, unsigned long *arg)
 206 {
 207         struct atm_qdisc_data *p = qdisc_priv(sch);
 208         struct atm_flow_data *flow = (struct atm_flow_data *)*arg;
 209         struct atm_flow_data *excess = NULL;
 210         struct nlattr *opt = tca[TCA_OPTIONS];
 211         struct nlattr *tb[TCA_ATM_MAX + 1];
 212         struct socket *sock;
 213         int fd, error, hdr_len;
 214         void *hdr;
 215
 216         pr_debug("atm_tc_change(sch %p,[qdisc %p],classid %x,parent %x,"
 217                 "flow %p,opt %p)\n", sch, p, classid, parent, flow, opt);
 218         /*
 219          * The concept of parents doesn't apply for this qdisc.
 220          */
 221         if (parent && parent != TC_H_ROOT && parent != sch->handle)
 222                 return -EINVAL;
 223         /*
 224          * ATM classes cannot be changed. In order to change properties of the
 225          * ATM connection, that socket needs to be modified directly (via the
 226          * native ATM API. In order to send a flow to a different VC, the old
 227          * class needs to be removed and a new one added. (This may be changed
 228          * later.)
 229          */
 230         if (flow)
 231                 return -EBUSY;
 232         if (opt == NULL)
 233                 return -EINVAL;
 234
 235         error = nla_parse_nested(tb, TCA_ATM_MAX, opt, atm_policy);
 236         if (error < 0)
 237                 return error;
 238
 239         if (!tb[TCA_ATM_FD])
 240                 return -EINVAL;
 241         fd = nla_get_u32(tb[TCA_ATM_FD]);
 242         pr_debug("atm_tc_change: fd %d\n", fd);
 243         if (tb[TCA_ATM_HDR]) {
 244                 hdr_len = nla_len(tb[TCA_ATM_HDR]);
 245                 hdr = nla_data(tb[TCA_ATM_HDR]);
 246         } else {
 247                 hdr_len = RFC1483LLC_LEN;
 248                 hdr = NULL;     /* default LLC/SNAP for IP */
 249         }
 250         if (!tb[TCA_ATM_EXCESS])
 251                 excess = NULL;
 252         else {
 253                 excess = (struct atm_flow_data *)
 254                         atm_tc_get(sch, nla_get_u32(tb[TCA_ATM_EXCESS]));
 255                 if (!excess)
 256                         return -ENOENT;
 257         }
 258         pr_debug("atm_tc_change: type %d, payload %d, hdr_len %d\n",
 259                  opt->nla_type, nla_len(opt), hdr_len);
 260         sock = sockfd_lookup(fd, &error);
 261         if (!sock)
 262                 return error;   /* f_count++ */
 263         pr_debug("atm_tc_change: f_count %ld\n", file_count(sock->file));
 264         if (sock->ops->family != PF_ATMSVC && sock->ops->family != PF_ATMPVC) {
 265                 error = -EPROTOTYPE;
 266                 goto err_out;
 267         }
 268         /* @@@ should check if the socket is really operational or we'll crash
 269            on vcc->send */
 270         if (classid) {
 271                 if (TC_H_MAJ(classid ^ sch->handle)) {
 272                         pr_debug("atm_tc_change: classid mismatch\n");
 273                         error = -EINVAL;
 274                         goto err_out;
 275                 }
 276                 if (find_flow(p, flow)) {
 277                         error = -EEXIST;
 278                         goto err_out;
 279                 }
 280         } else {
 281                 int i;
 282                 unsigned long cl;
 283
 284                 for (i = 1; i < 0x8000; i++) {
 285                         classid = TC_H_MAKE(sch->handle, 0x8000 | i);
 286                         cl = atm_tc_get(sch, classid);
 287                         if (!cl)
 288                                 break;
 289                         atm_tc_put(sch, cl);
 290                 }
 291         }
 292         pr_debug("atm_tc_change: new id %x\n", classid);
 293         flow = kzalloc(sizeof(struct atm_flow_data) + hdr_len, GFP_KERNEL);
 294         pr_debug("atm_tc_change: flow %p\n", flow);
 295         if (!flow) {
 296                 error = -ENOBUFS;
 297                 goto err_out;
 298         }
 299         flow->filter_list = NULL;
 300         flow->q = qdisc_create_dflt(qdisc_dev(sch), sch->dev_queue,
 301                                     &pfifo_qdisc_ops, classid);
 302         if (!flow->q)
 303                 flow->q = &noop_qdisc;
 304         pr_debug("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         pr_debug("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 = qdisc_priv(sch);
 334         struct atm_flow_data *flow = (struct atm_flow_data *)arg;
 335
 336         pr_debug("atm_tc_delete(sch %p,[qdisc %p],flow %p)\n", sch, p, flow);
 337         if (!find_flow(qdisc_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 = qdisc_priv(sch);
 358         struct atm_flow_data *flow;
 359
 360         pr_debug("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 = qdisc_priv(sch);
 376         struct atm_flow_data *flow = (struct atm_flow_data *)cl;
 377
 378         pr_debug("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 = qdisc_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         pr_debug("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 | __NET_XMIT_STOLEN;
 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         ret = qdisc_enqueue(skb, flow->q);
 434         if (ret != 0) {
 435 drop: __maybe_unused
 436                 if (net_xmit_drop_count(ret)) {
 437                         sch->qstats.drops++;
 438                         if (flow)
 439                                 flow->qstats.drops++;
 440                 }
 441                 return ret;
 442         }
 443         sch->bstats.bytes += qdisc_pkt_len(skb);
 444         sch->bstats.packets++;
 445         flow->bstats.bytes += qdisc_pkt_len(skb);
 446         flow->bstats.packets++;
 447         /*
 448          * Okay, this may seem weird. We pretend we've dropped the packet if
 449          * it goes via ATM. The reason for this is that the outer qdisc
 450          * expects to be able to q->dequeue the packet later on if we return
 451          * success at this place. Also, sch->q.qdisc needs to reflect whether
 452          * there is a packet egligible for dequeuing or not. Note that the
 453          * statistics of the outer qdisc are necessarily wrong because of all
 454          * this. There's currently no correct solution for this.
 455          */
 456         if (flow == &p->link) {
 457                 sch->q.qlen++;
 458                 return 0;
 459         }
 460         tasklet_schedule(&p->task);
 461         return NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
 462 }
 463
 464 /*
 465  * Dequeue packets and send them over ATM. Note that we quite deliberately
 466  * avoid checking net_device's flow control here, simply because sch_atm
 467  * uses its own channels, which have nothing to do with any CLIP/LANE/or
 468  * non-ATM interfaces.
 469  */
 470
 471 static void sch_atm_dequeue(unsigned long data)
 472 {
 473         struct Qdisc *sch = (struct Qdisc *)data;
 474         struct atm_qdisc_data *p = qdisc_priv(sch);
 475         struct atm_flow_data *flow;
 476         struct sk_buff *skb;
 477
 478         pr_debug("sch_atm_dequeue(sch %p,[qdisc %p])\n", sch, p);
 479         for (flow = p->link.next; flow; flow = flow->next)
 480                 /*
 481                  * If traffic is properly shaped, this won't generate nasty
 482                  * little bursts. Otherwise, it may ... (but that's okay)
 483                  */
 484                 while ((skb = flow->q->ops->peek(flow->q))) {
 485                         if (!atm_may_send(flow->vcc, skb->truesize))
 486                                 break;
 487
 488                         skb = qdisc_dequeue_peeked(flow->q);
 489                         if (unlikely(!skb))
 490                                 break;
 491
 492                         pr_debug("atm_tc_dequeue: sending on class %p\n", flow);
 493                         /* remove any LL header somebody else has attached */
 494                         skb_pull(skb, skb_network_offset(skb));
 495                         if (skb_headroom(skb) < flow->hdr_len) {
 496                                 struct sk_buff *new;
 497
 498                                 new = skb_realloc_headroom(skb, flow->hdr_len);
 499                                 dev_kfree_skb(skb);
 500                                 if (!new)
 501                                         continue;
 502                                 skb = new;
 503                         }
 504                         pr_debug("sch_atm_dequeue: ip %p, data %p\n",
 505                                  skb_network_header(skb), skb->data);
 506                         ATM_SKB(skb)->vcc = flow->vcc;
 507                         memcpy(skb_push(skb, flow->hdr_len), flow->hdr,
 508                                flow->hdr_len);
 509                         atomic_add(skb->truesize,
 510                                    &sk_atm(flow->vcc)->sk_wmem_alloc);
 511                         /* atm.atm_options are already set by atm_tc_enqueue */
 512                         flow->vcc->send(flow->vcc, skb);
 513                 }
 514 }
 515
 516 static struct sk_buff *atm_tc_dequeue(struct Qdisc *sch)
 517 {
 518         struct atm_qdisc_data *p = qdisc_priv(sch);
 519         struct sk_buff *skb;
 520
 521         pr_debug("atm_tc_dequeue(sch %p,[qdisc %p])\n", sch, p);
 522         tasklet_schedule(&p->task);
 523         skb = qdisc_dequeue_peeked(p->link.q);
 524         if (skb)
 525                 sch->q.qlen--;
 526         return skb;
 527 }
 528
 529 static struct sk_buff *atm_tc_peek(struct Qdisc *sch)
 530 {
 531         struct atm_qdisc_data *p = qdisc_priv(sch);
 532
 533         pr_debug("atm_tc_peek(sch %p,[qdisc %p])\n", sch, p);
 534
 535         return p->link.q->ops->peek(p->link.q);
 536 }
 537
 538 static unsigned int atm_tc_drop(struct Qdisc *sch)
 539 {
 540         struct atm_qdisc_data *p = qdisc_priv(sch);
 541         struct atm_flow_data *flow;
 542         unsigned int len;
 543
 544         pr_debug("atm_tc_drop(sch %p,[qdisc %p])\n", sch, p);
 545         for (flow = p->flows; flow; flow = flow->next)
 546                 if (flow->q->ops->drop && (len = flow->q->ops->drop(flow->q)))
 547                         return len;
 548         return 0;
 549 }
 550
 551 static int atm_tc_init(struct Qdisc *sch, struct nlattr *opt)
 552 {
 553         struct atm_qdisc_data *p = qdisc_priv(sch);
 554
 555         pr_debug("atm_tc_init(sch %p,[qdisc %p],opt %p)\n", sch, p, opt);
 556         p->flows = &p->link;
 557         p->link.q = qdisc_create_dflt(qdisc_dev(sch), sch->dev_queue,
 558                                       &pfifo_qdisc_ops, sch->handle);
 559         if (!p->link.q)
 560                 p->link.q = &noop_qdisc;
 561         pr_debug("atm_tc_init: link (%p) qdisc %p\n", &p->link, p->link.q);
 562         p->link.filter_list = NULL;
 563         p->link.vcc = NULL;
 564         p->link.sock = NULL;
 565         p->link.classid = sch->handle;
 566         p->link.ref = 1;
 567         p->link.next = NULL;
 568         tasklet_init(&p->task, sch_atm_dequeue, (unsigned long)sch);
 569         return 0;
 570 }
 571
 572 static void atm_tc_reset(struct Qdisc *sch)
 573 {
 574         struct atm_qdisc_data *p = qdisc_priv(sch);
 575         struct atm_flow_data *flow;
 576
 577         pr_debug("atm_tc_reset(sch %p,[qdisc %p])\n", sch, p);
 578         for (flow = p->flows; flow; flow = flow->next)
 579                 qdisc_reset(flow->q);
 580         sch->q.qlen = 0;
 581 }
 582
 583 static void atm_tc_destroy(struct Qdisc *sch)
 584 {
 585         struct atm_qdisc_data *p = qdisc_priv(sch);
 586         struct atm_flow_data *flow;
 587
 588         pr_debug("atm_tc_destroy(sch %p,[qdisc %p])\n", sch, p);
 589         for (flow = p->flows; flow; flow = flow->next)
 590                 tcf_destroy_chain(&flow->filter_list);
 591
 592         /* races ? */
 593         while ((flow = p->flows)) {
 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 = qdisc_priv(sch);
 612         struct atm_flow_data *flow = (struct atm_flow_data *)cl;
 613         struct nlattr *nest;
 614
 615         pr_debug("atm_tc_dump_class(sch %p,[qdisc %p],flow %p,skb %p,tcm %p)\n",
 616                 sch, p, flow, skb, tcm);
 617         if (!find_flow(p, flow))
 618                 return -EINVAL;
 619         tcm->tcm_handle = flow->classid;
 620         tcm->tcm_info = flow->q->handle;
 621
 622         nest = nla_nest_start(skb, TCA_OPTIONS);
 623         if (nest == NULL)
 624                 goto nla_put_failure;
 625
 626         NLA_PUT(skb, TCA_ATM_HDR, flow->hdr_len, flow->hdr);
 627         if (flow->vcc) {
 628                 struct sockaddr_atmpvc pvc;
 629                 int state;
 630
 631                 pvc.sap_family = AF_ATMPVC;
 632                 pvc.sap_addr.itf = flow->vcc->dev ? flow->vcc->dev->number : -1;
 633                 pvc.sap_addr.vpi = flow->vcc->vpi;
 634                 pvc.sap_addr.vci = flow->vcc->vci;
 635                 NLA_PUT(skb, TCA_ATM_ADDR, sizeof(pvc), &pvc);
 636                 state = ATM_VF2VS(flow->vcc->flags);
 637                 NLA_PUT_U32(skb, TCA_ATM_STATE, state);
 638         }
 639         if (flow->excess)
 640                 NLA_PUT_U32(skb, TCA_ATM_EXCESS, flow->classid);
 641         else {
 642                 NLA_PUT_U32(skb, TCA_ATM_EXCESS, 0);
 643         }
 644
 645         nla_nest_end(skb, nest);
 646         return skb->len;
 647
 648 nla_put_failure:
 649         nla_nest_cancel(skb, nest);
 650         return -1;
 651 }
 652 static int
 653 atm_tc_dump_class_stats(struct Qdisc *sch, unsigned long arg,
 654                         struct gnet_dump *d)
 655 {
 656         struct atm_flow_data *flow = (struct atm_flow_data *)arg;
 657
 658         flow->qstats.qlen = flow->q->q.qlen;
 659
 660         if (gnet_stats_copy_basic(d, &flow->bstats) < 0 ||
 661             gnet_stats_copy_queue(d, &flow->qstats) < 0)
 662                 return -1;
 663
 664         return 0;
 665 }
 666
 667 static int atm_tc_dump(struct Qdisc *sch, struct sk_buff *skb)
 668 {
 669         return 0;
 670 }
 671
 672 static const struct Qdisc_class_ops atm_class_ops = {
 673         .graft          = atm_tc_graft,
 674         .leaf           = atm_tc_leaf,
 675         .get            = atm_tc_get,
 676         .put            = atm_tc_put,
 677         .change         = atm_tc_change,
 678         .delete         = atm_tc_delete,
 679         .walk           = atm_tc_walk,
 680         .tcf_chain      = atm_tc_find_tcf,
 681         .bind_tcf       = atm_tc_bind_filter,
 682         .unbind_tcf     = atm_tc_put,
 683         .dump           = atm_tc_dump_class,
 684         .dump_stats     = atm_tc_dump_class_stats,
 685 };
 686
 687 static struct Qdisc_ops atm_qdisc_ops __read_mostly = {
 688         .cl_ops         = &atm_class_ops,
 689         .id             = "atm",
 690         .priv_size      = sizeof(struct atm_qdisc_data),
 691         .enqueue        = atm_tc_enqueue,
 692         .dequeue        = atm_tc_dequeue,
 693         .peek           = atm_tc_peek,
 694         .drop           = atm_tc_drop,
 695         .init           = atm_tc_init,
 696         .reset          = atm_tc_reset,
 697         .destroy        = atm_tc_destroy,
 698         .dump           = atm_tc_dump,
 699         .owner          = THIS_MODULE,
 700 };
 701
 702 static int __init atm_init(void)
 703 {
 704         return register_qdisc(&atm_qdisc_ops);
 705 }
 706
 707 static void __exit atm_exit(void)
 708 {
 709         unregister_qdisc(&atm_qdisc_ops);
 710 }
 711
 712 module_init(atm_init)
 713 module_exit(atm_exit)
 714 MODULE_LICENSE("GPL");