f9eac0818d1814966e8362bedc8e49225f9981f9
[linux-3.10.git] / 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 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;           /* requeue 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 = xchg(&flow->q, new);
106         if (*old)
107                 qdisc_reset(*old);
108         return 0;
109 }
110
111 static struct Qdisc *atm_tc_leaf(struct Qdisc *sch, unsigned long cl)
112 {
113         struct atm_flow_data *flow = (struct atm_flow_data *)cl;
114
115         pr_debug("atm_tc_leaf(sch %p,flow %p)\n", sch, flow);
116         return flow ? flow->q : NULL;
117 }
118
119 static unsigned long atm_tc_get(struct Qdisc *sch, u32 classid)
120 {
121         struct atm_qdisc_data *p __maybe_unused = qdisc_priv(sch);
122         struct atm_flow_data *flow;
123
124         pr_debug("atm_tc_get(sch %p,[qdisc %p],classid %x)\n", sch, p, classid);
125         flow = lookup_flow(sch, classid);
126         if (flow)
127                 flow->ref++;
128         pr_debug("atm_tc_get: flow %p\n", flow);
129         return (unsigned long)flow;
130 }
131
132 static unsigned long atm_tc_bind_filter(struct Qdisc *sch,
133                                         unsigned long parent, u32 classid)
134 {
135         return atm_tc_get(sch, classid);
136 }
137
138 /*
139  * atm_tc_put handles all destructions, including the ones that are explicitly
140  * requested (atm_tc_destroy, etc.). The assumption here is that we never drop
141  * anything that still seems to be in use.
142  */
143 static void atm_tc_put(struct Qdisc *sch, unsigned long cl)
144 {
145         struct atm_qdisc_data *p = qdisc_priv(sch);
146         struct atm_flow_data *flow = (struct atm_flow_data *)cl;
147         struct atm_flow_data **prev;
148
149         pr_debug("atm_tc_put(sch %p,[qdisc %p],flow %p)\n", sch, p, flow);
150         if (--flow->ref)
151                 return;
152         pr_debug("atm_tc_put: destroying\n");
153         for (prev = &p->flows; *prev; prev = &(*prev)->next)
154                 if (*prev == flow)
155                         break;
156         if (!*prev) {
157                 printk(KERN_CRIT "atm_tc_put: class %p not found\n", flow);
158                 return;
159         }
160         *prev = flow->next;
161         pr_debug("atm_tc_put: qdisc %p\n", flow->q);
162         qdisc_destroy(flow->q);
163         tcf_destroy_chain(&flow->filter_list);
164         if (flow->sock) {
165                 pr_debug("atm_tc_put: f_count %ld\n",
166                         file_count(flow->sock->file));
167                 flow->vcc->pop = flow->old_pop;
168                 sockfd_put(flow->sock);
169         }
170         if (flow->excess)
171                 atm_tc_put(sch, (unsigned long)flow->excess);
172         if (flow != &p->link)
173                 kfree(flow);
174         /*
175          * If flow == &p->link, the qdisc no longer works at this point and
176          * needs to be removed. (By the caller of atm_tc_put.)
177          */
178 }
179
180 static void sch_atm_pop(struct atm_vcc *vcc, struct sk_buff *skb)
181 {
182         struct atm_qdisc_data *p = VCC2FLOW(vcc)->parent;
183
184         pr_debug("sch_atm_pop(vcc %p,skb %p,[qdisc %p])\n", vcc, skb, p);
185         VCC2FLOW(vcc)->old_pop(vcc, skb);
186         tasklet_schedule(&p->task);
187 }
188
189 static const u8 llc_oui_ip[] = {
190         0xaa,                   /* DSAP: non-ISO */
191         0xaa,                   /* SSAP: non-ISO */
192         0x03,                   /* Ctrl: Unnumbered Information Command PDU */
193         0x00,                   /* OUI: EtherType */
194         0x00, 0x00,
195         0x08, 0x00
196 };                              /* Ethertype IP (0800) */
197
198 static const struct nla_policy atm_policy[TCA_ATM_MAX + 1] = {
199         [TCA_ATM_FD]            = { .type = NLA_U32 },
200         [TCA_ATM_EXCESS]        = { .type = NLA_U32 },
201 };
202
203 static int atm_tc_change(struct Qdisc *sch, u32 classid, u32 parent,
204                          struct nlattr **tca, unsigned long *arg)
205 {
206         struct atm_qdisc_data *p = qdisc_priv(sch);
207         struct atm_flow_data *flow = (struct atm_flow_data *)*arg;
208         struct atm_flow_data *excess = NULL;
209         struct nlattr *opt = tca[TCA_OPTIONS];
210         struct nlattr *tb[TCA_ATM_MAX + 1];
211         struct socket *sock;
212         int fd, error, hdr_len;
213         void *hdr;
214
215         pr_debug("atm_tc_change(sch %p,[qdisc %p],classid %x,parent %x,"
216                 "flow %p,opt %p)\n", sch, p, classid, parent, flow, opt);
217         /*
218          * The concept of parents doesn't apply for this qdisc.
219          */
220         if (parent && parent != TC_H_ROOT && parent != sch->handle)
221                 return -EINVAL;
222         /*
223          * ATM classes cannot be changed. In order to change properties of the
224          * ATM connection, that socket needs to be modified directly (via the
225          * native ATM API. In order to send a flow to a different VC, the old
226          * class needs to be removed and a new one added. (This may be changed
227          * later.)
228          */
229         if (flow)
230                 return -EBUSY;
231         if (opt == NULL)
232                 return -EINVAL;
233
234         error = nla_parse_nested(tb, TCA_ATM_MAX, opt, atm_policy);
235         if (error < 0)
236                 return error;
237
238         if (!tb[TCA_ATM_FD])
239                 return -EINVAL;
240         fd = nla_get_u32(tb[TCA_ATM_FD]);
241         pr_debug("atm_tc_change: fd %d\n", fd);
242         if (tb[TCA_ATM_HDR]) {
243                 hdr_len = nla_len(tb[TCA_ATM_HDR]);
244                 hdr = nla_data(tb[TCA_ATM_HDR]);
245         } else {
246                 hdr_len = RFC1483LLC_LEN;
247                 hdr = NULL;     /* default LLC/SNAP for IP */
248         }
249         if (!tb[TCA_ATM_EXCESS])
250                 excess = NULL;
251         else {
252                 excess = (struct atm_flow_data *)
253                         atm_tc_get(sch, nla_get_u32(tb[TCA_ATM_EXCESS]));
254                 if (!excess)
255                         return -ENOENT;
256         }
257         pr_debug("atm_tc_change: type %d, payload %d, hdr_len %d\n",
258                  opt->nla_type, nla_len(opt), hdr_len);
259         sock = sockfd_lookup(fd, &error);
260         if (!sock)
261                 return error;   /* f_count++ */
262         pr_debug("atm_tc_change: f_count %ld\n", file_count(sock->file));
263         if (sock->ops->family != PF_ATMSVC && sock->ops->family != PF_ATMPVC) {
264                 error = -EPROTOTYPE;
265                 goto err_out;
266         }
267         /* @@@ should check if the socket is really operational or we'll crash
268            on vcc->send */
269         if (classid) {
270                 if (TC_H_MAJ(classid ^ sch->handle)) {
271                         pr_debug("atm_tc_change: classid mismatch\n");
272                         error = -EINVAL;
273                         goto err_out;
274                 }
275                 if (find_flow(p, flow)) {
276                         error = -EEXIST;
277                         goto err_out;
278                 }
279         } else {
280                 int i;
281                 unsigned long cl;
282
283                 for (i = 1; i < 0x8000; i++) {
284                         classid = TC_H_MAKE(sch->handle, 0x8000 | i);
285                         cl = atm_tc_get(sch, classid);
286                         if (!cl)
287                                 break;
288                         atm_tc_put(sch, cl);
289                 }
290         }
291         pr_debug("atm_tc_change: new id %x\n", classid);
292         flow = kzalloc(sizeof(struct atm_flow_data) + hdr_len, GFP_KERNEL);
293         pr_debug("atm_tc_change: flow %p\n", flow);
294         if (!flow) {
295                 error = -ENOBUFS;
296                 goto err_out;
297         }
298         flow->filter_list = NULL;
299         flow->q = qdisc_create_dflt(qdisc_dev(sch), sch->dev_queue,
300                                     &pfifo_qdisc_ops, classid);
301         if (!flow->q)
302                 flow->q = &noop_qdisc;
303         pr_debug("atm_tc_change: qdisc %p\n", flow->q);
304         flow->sock = sock;
305         flow->vcc = ATM_SD(sock);       /* speedup */
306         flow->vcc->user_back = flow;
307         pr_debug("atm_tc_change: vcc %p\n", flow->vcc);
308         flow->old_pop = flow->vcc->pop;
309         flow->parent = p;
310         flow->vcc->pop = sch_atm_pop;
311         flow->classid = classid;
312         flow->ref = 1;
313         flow->excess = excess;
314         flow->next = p->link.next;
315         p->link.next = flow;
316         flow->hdr_len = hdr_len;
317         if (hdr)
318                 memcpy(flow->hdr, hdr, hdr_len);
319         else
320                 memcpy(flow->hdr, llc_oui_ip, sizeof(llc_oui_ip));
321         *arg = (unsigned long)flow;
322         return 0;
323 err_out:
324         if (excess)
325                 atm_tc_put(sch, (unsigned long)excess);
326         sockfd_put(sock);
327         return error;
328 }
329
330 static int atm_tc_delete(struct Qdisc *sch, unsigned long arg)
331 {
332         struct atm_qdisc_data *p = qdisc_priv(sch);
333         struct atm_flow_data *flow = (struct atm_flow_data *)arg;
334
335         pr_debug("atm_tc_delete(sch %p,[qdisc %p],flow %p)\n", sch, p, flow);
336         if (!find_flow(qdisc_priv(sch), flow))
337                 return -EINVAL;
338         if (flow->filter_list || flow == &p->link)
339                 return -EBUSY;
340         /*
341          * Reference count must be 2: one for "keepalive" (set at class
342          * creation), and one for the reference held when calling delete.
343          */
344         if (flow->ref < 2) {
345                 printk(KERN_ERR "atm_tc_delete: flow->ref == %d\n", flow->ref);
346                 return -EINVAL;
347         }
348         if (flow->ref > 2)
349                 return -EBUSY;  /* catch references via excess, etc. */
350         atm_tc_put(sch, arg);
351         return 0;
352 }
353
354 static void atm_tc_walk(struct Qdisc *sch, struct qdisc_walker *walker)
355 {
356         struct atm_qdisc_data *p = qdisc_priv(sch);
357         struct atm_flow_data *flow;
358
359         pr_debug("atm_tc_walk(sch %p,[qdisc %p],walker %p)\n", sch, p, walker);
360         if (walker->stop)
361                 return;
362         for (flow = p->flows; flow; flow = flow->next) {
363                 if (walker->count >= walker->skip)
364                         if (walker->fn(sch, (unsigned long)flow, walker) < 0) {
365                                 walker->stop = 1;
366                                 break;
367                         }
368                 walker->count++;
369         }
370 }
371
372 static struct tcf_proto **atm_tc_find_tcf(struct Qdisc *sch, unsigned long cl)
373 {
374         struct atm_qdisc_data *p = qdisc_priv(sch);
375         struct atm_flow_data *flow = (struct atm_flow_data *)cl;
376
377         pr_debug("atm_tc_find_tcf(sch %p,[qdisc %p],flow %p)\n", sch, p, flow);
378         return flow ? &flow->filter_list : &p->link.filter_list;
379 }
380
381 /* --------------------------- Qdisc operations ---------------------------- */
382
383 static int atm_tc_enqueue(struct sk_buff *skb, struct Qdisc *sch)
384 {
385         struct atm_qdisc_data *p = qdisc_priv(sch);
386         struct atm_flow_data *flow = NULL;      /* @@@ */
387         struct tcf_result res;
388         int result;
389         int ret = NET_XMIT_POLICED;
390
391         pr_debug("atm_tc_enqueue(skb %p,sch %p,[qdisc %p])\n", skb, sch, p);
392         result = TC_POLICE_OK;  /* be nice to gcc */
393         if (TC_H_MAJ(skb->priority) != sch->handle ||
394             !(flow = (struct atm_flow_data *)atm_tc_get(sch, skb->priority)))
395                 for (flow = p->flows; flow; flow = flow->next)
396                         if (flow->filter_list) {
397                                 result = tc_classify_compat(skb,
398                                                             flow->filter_list,
399                                                             &res);
400                                 if (result < 0)
401                                         continue;
402                                 flow = (struct atm_flow_data *)res.class;
403                                 if (!flow)
404                                         flow = lookup_flow(sch, res.classid);
405                                 break;
406                         }
407         if (!flow)
408                 flow = &p->link;
409         else {
410                 if (flow->vcc)
411                         ATM_SKB(skb)->atm_options = flow->vcc->atm_options;
412                 /*@@@ looks good ... but it's not supposed to work :-) */
413 #ifdef CONFIG_NET_CLS_ACT
414                 switch (result) {
415                 case TC_ACT_QUEUED:
416                 case TC_ACT_STOLEN:
417                         kfree_skb(skb);
418                         return NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
419                 case TC_ACT_SHOT:
420                         kfree_skb(skb);
421                         goto drop;
422                 case TC_POLICE_RECLASSIFY:
423                         if (flow->excess)
424                                 flow = flow->excess;
425                         else
426                                 ATM_SKB(skb)->atm_options |= ATM_ATMOPT_CLP;
427                         break;
428                 }
429 #endif
430         }
431
432         ret = qdisc_enqueue(skb, flow->q);
433         if (ret != 0) {
434 drop: __maybe_unused
435                 if (net_xmit_drop_count(ret)) {
436                         sch->qstats.drops++;
437                         if (flow)
438                                 flow->qstats.drops++;
439                 }
440                 return ret;
441         }
442         sch->bstats.bytes += qdisc_pkt_len(skb);
443         sch->bstats.packets++;
444         flow->bstats.bytes += qdisc_pkt_len(skb);
445         flow->bstats.packets++;
446         /*
447          * Okay, this may seem weird. We pretend we've dropped the packet if
448          * it goes via ATM. The reason for this is that the outer qdisc
449          * expects to be able to q->dequeue the packet later on if we return
450          * success at this place. Also, sch->q.qdisc needs to reflect whether
451          * there is a packet egligible for dequeuing or not. Note that the
452          * statistics of the outer qdisc are necessarily wrong because of all
453          * this. There's currently no correct solution for this.
454          */
455         if (flow == &p->link) {
456                 sch->q.qlen++;
457                 return 0;
458         }
459         tasklet_schedule(&p->task);
460         return NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
461 }
462
463 /*
464  * Dequeue packets and send them over ATM. Note that we quite deliberately
465  * avoid checking net_device's flow control here, simply because sch_atm
466  * uses its own channels, which have nothing to do with any CLIP/LANE/or
467  * non-ATM interfaces.
468  */
469
470 static void sch_atm_dequeue(unsigned long data)
471 {
472         struct Qdisc *sch = (struct Qdisc *)data;
473         struct atm_qdisc_data *p = qdisc_priv(sch);
474         struct atm_flow_data *flow;
475         struct sk_buff *skb;
476
477         pr_debug("sch_atm_dequeue(sch %p,[qdisc %p])\n", sch, p);
478         for (flow = p->link.next; flow; flow = flow->next)
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->dequeue(flow->q))) {
484                         if (!atm_may_send(flow->vcc, skb->truesize)) {
485                                 (void)flow->q->ops->requeue(skb, flow->q);
486                                 break;
487                         }
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                         atomic_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 static struct sk_buff *atm_tc_dequeue(struct Qdisc *sch)
513 {
514         struct atm_qdisc_data *p = qdisc_priv(sch);
515         struct sk_buff *skb;
516
517         pr_debug("atm_tc_dequeue(sch %p,[qdisc %p])\n", sch, p);
518         tasklet_schedule(&p->task);
519         skb = p->link.q->dequeue(p->link.q);
520         if (skb)
521                 sch->q.qlen--;
522         return skb;
523 }
524
525 static struct sk_buff *atm_tc_peek(struct Qdisc *sch)
526 {
527         struct atm_qdisc_data *p = qdisc_priv(sch);
528
529         pr_debug("atm_tc_peek(sch %p,[qdisc %p])\n", sch, p);
530
531         return p->link.q->ops->peek(p->link.q);
532 }
533
534 static int atm_tc_requeue(struct sk_buff *skb, struct Qdisc *sch)
535 {
536         struct atm_qdisc_data *p = qdisc_priv(sch);
537         int ret;
538
539         pr_debug("atm_tc_requeue(skb %p,sch %p,[qdisc %p])\n", skb, sch, p);
540         ret = p->link.q->ops->requeue(skb, p->link.q);
541         if (!ret) {
542                 sch->q.qlen++;
543                 sch->qstats.requeues++;
544         } else if (net_xmit_drop_count(ret)) {
545                 sch->qstats.drops++;
546                 p->link.qstats.drops++;
547         }
548         return ret;
549 }
550
551 static unsigned int atm_tc_drop(struct Qdisc *sch)
552 {
553         struct atm_qdisc_data *p = qdisc_priv(sch);
554         struct atm_flow_data *flow;
555         unsigned int len;
556
557         pr_debug("atm_tc_drop(sch %p,[qdisc %p])\n", sch, p);
558         for (flow = p->flows; flow; flow = flow->next)
559                 if (flow->q->ops->drop && (len = flow->q->ops->drop(flow->q)))
560                         return len;
561         return 0;
562 }
563
564 static int atm_tc_init(struct Qdisc *sch, struct nlattr *opt)
565 {
566         struct atm_qdisc_data *p = qdisc_priv(sch);
567
568         pr_debug("atm_tc_init(sch %p,[qdisc %p],opt %p)\n", sch, p, opt);
569         p->flows = &p->link;
570         p->link.q = qdisc_create_dflt(qdisc_dev(sch), sch->dev_queue,
571                                       &pfifo_qdisc_ops, sch->handle);
572         if (!p->link.q)
573                 p->link.q = &noop_qdisc;
574         pr_debug("atm_tc_init: link (%p) qdisc %p\n", &p->link, p->link.q);
575         p->link.filter_list = NULL;
576         p->link.vcc = NULL;
577         p->link.sock = NULL;
578         p->link.classid = sch->handle;
579         p->link.ref = 1;
580         p->link.next = NULL;
581         tasklet_init(&p->task, sch_atm_dequeue, (unsigned long)sch);
582         return 0;
583 }
584
585 static void atm_tc_reset(struct Qdisc *sch)
586 {
587         struct atm_qdisc_data *p = qdisc_priv(sch);
588         struct atm_flow_data *flow;
589
590         pr_debug("atm_tc_reset(sch %p,[qdisc %p])\n", sch, p);
591         for (flow = p->flows; flow; flow = flow->next)
592                 qdisc_reset(flow->q);
593         sch->q.qlen = 0;
594 }
595
596 static void atm_tc_destroy(struct Qdisc *sch)
597 {
598         struct atm_qdisc_data *p = qdisc_priv(sch);
599         struct atm_flow_data *flow;
600
601         pr_debug("atm_tc_destroy(sch %p,[qdisc %p])\n", sch, p);
602         for (flow = p->flows; flow; flow = flow->next)
603                 tcf_destroy_chain(&flow->filter_list);
604
605         /* races ? */
606         while ((flow = p->flows)) {
607                 if (flow->ref > 1)
608                         printk(KERN_ERR "atm_destroy: %p->ref = %d\n", flow,
609                                flow->ref);
610                 atm_tc_put(sch, (unsigned long)flow);
611                 if (p->flows == flow) {
612                         printk(KERN_ERR "atm_destroy: putting flow %p didn't "
613                                "kill it\n", flow);
614                         p->flows = flow->next;  /* brute force */
615                         break;
616                 }
617         }
618         tasklet_kill(&p->task);
619 }
620
621 static int atm_tc_dump_class(struct Qdisc *sch, unsigned long cl,
622                              struct sk_buff *skb, struct tcmsg *tcm)
623 {
624         struct atm_qdisc_data *p = qdisc_priv(sch);
625         struct atm_flow_data *flow = (struct atm_flow_data *)cl;
626         struct nlattr *nest;
627
628         pr_debug("atm_tc_dump_class(sch %p,[qdisc %p],flow %p,skb %p,tcm %p)\n",
629                 sch, p, flow, skb, tcm);
630         if (!find_flow(p, flow))
631                 return -EINVAL;
632         tcm->tcm_handle = flow->classid;
633         tcm->tcm_info = flow->q->handle;
634
635         nest = nla_nest_start(skb, TCA_OPTIONS);
636         if (nest == NULL)
637                 goto nla_put_failure;
638
639         NLA_PUT(skb, TCA_ATM_HDR, flow->hdr_len, flow->hdr);
640         if (flow->vcc) {
641                 struct sockaddr_atmpvc pvc;
642                 int state;
643
644                 pvc.sap_family = AF_ATMPVC;
645                 pvc.sap_addr.itf = flow->vcc->dev ? flow->vcc->dev->number : -1;
646                 pvc.sap_addr.vpi = flow->vcc->vpi;
647                 pvc.sap_addr.vci = flow->vcc->vci;
648                 NLA_PUT(skb, TCA_ATM_ADDR, sizeof(pvc), &pvc);
649                 state = ATM_VF2VS(flow->vcc->flags);
650                 NLA_PUT_U32(skb, TCA_ATM_STATE, state);
651         }
652         if (flow->excess)
653                 NLA_PUT_U32(skb, TCA_ATM_EXCESS, flow->classid);
654         else {
655                 NLA_PUT_U32(skb, TCA_ATM_EXCESS, 0);
656         }
657
658         nla_nest_end(skb, nest);
659         return skb->len;
660
661 nla_put_failure:
662         nla_nest_cancel(skb, nest);
663         return -1;
664 }
665 static int
666 atm_tc_dump_class_stats(struct Qdisc *sch, unsigned long arg,
667                         struct gnet_dump *d)
668 {
669         struct atm_flow_data *flow = (struct atm_flow_data *)arg;
670
671         flow->qstats.qlen = flow->q->q.qlen;
672
673         if (gnet_stats_copy_basic(d, &flow->bstats) < 0 ||
674             gnet_stats_copy_queue(d, &flow->qstats) < 0)
675                 return -1;
676
677         return 0;
678 }
679
680 static int atm_tc_dump(struct Qdisc *sch, struct sk_buff *skb)
681 {
682         return 0;
683 }
684
685 static const struct Qdisc_class_ops atm_class_ops = {
686         .graft          = atm_tc_graft,
687         .leaf           = atm_tc_leaf,
688         .get            = atm_tc_get,
689         .put            = atm_tc_put,
690         .change         = atm_tc_change,
691         .delete         = atm_tc_delete,
692         .walk           = atm_tc_walk,
693         .tcf_chain      = atm_tc_find_tcf,
694         .bind_tcf       = atm_tc_bind_filter,
695         .unbind_tcf     = atm_tc_put,
696         .dump           = atm_tc_dump_class,
697         .dump_stats     = atm_tc_dump_class_stats,
698 };
699
700 static struct Qdisc_ops atm_qdisc_ops __read_mostly = {
701         .cl_ops         = &atm_class_ops,
702         .id             = "atm",
703         .priv_size      = sizeof(struct atm_qdisc_data),
704         .enqueue        = atm_tc_enqueue,
705         .dequeue        = atm_tc_dequeue,
706         .peek           = atm_tc_peek,
707         .requeue        = atm_tc_requeue,
708         .drop           = atm_tc_drop,
709         .init           = atm_tc_init,
710         .reset          = atm_tc_reset,
711         .destroy        = atm_tc_destroy,
712         .dump           = atm_tc_dump,
713         .owner          = THIS_MODULE,
714 };
715
716 static int __init atm_init(void)
717 {
718         return register_qdisc(&atm_qdisc_ops);
719 }
720
721 static void __exit atm_exit(void)
722 {
723         unregister_qdisc(&atm_qdisc_ops);
724 }
725
726 module_init(atm_init)
727 module_exit(atm_exit)
728 MODULE_LICENSE("GPL");