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 
lookup_flow(struct Qdisc * sch,u32 classid)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 
atm_tc_graft(struct Qdisc * sch,unsigned long arg,struct Qdisc * new,struct Qdisc ** old,struct netlink_ext_ack * extack)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 
atm_tc_leaf(struct Qdisc * sch,unsigned long cl)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 
atm_tc_find(struct Qdisc * sch,u32 classid)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 
atm_tc_bind_filter(struct Qdisc * sch,unsigned long parent,u32 classid)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  */
atm_tc_put(struct Qdisc * sch,unsigned long cl)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_destroy(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 
sch_atm_pop(struct atm_vcc * vcc,struct sk_buff * skb)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 
atm_tc_change(struct Qdisc * sch,u32 classid,u32 parent,struct nlattr ** tca,unsigned long * arg,struct netlink_ext_ack * extack)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(tb, TCA_ATM_MAX, opt, atm_policy, NULL);
227 	if (error < 0)
228 		return error;
229 
230 	if (!tb[TCA_ATM_FD])
231 		return -EINVAL;
232 	fd = nla_get_u32(tb[TCA_ATM_FD]);
233 	pr_debug("atm_tc_change: fd %d\n", fd);
234 	if (tb[TCA_ATM_HDR]) {
235 		hdr_len = nla_len(tb[TCA_ATM_HDR]);
236 		hdr = nla_data(tb[TCA_ATM_HDR]);
237 	} else {
238 		hdr_len = RFC1483LLC_LEN;
239 		hdr = NULL;	/* default LLC/SNAP for IP */
240 	}
241 	if (!tb[TCA_ATM_EXCESS])
242 		excess = NULL;
243 	else {
244 		excess = (struct atm_flow_data *)
245 			atm_tc_find(sch, nla_get_u32(tb[TCA_ATM_EXCESS]));
246 		if (!excess)
247 			return -ENOENT;
248 	}
249 	pr_debug("atm_tc_change: type %d, payload %d, hdr_len %d\n",
250 		 opt->nla_type, nla_len(opt), hdr_len);
251 	sock = sockfd_lookup(fd, &error);
252 	if (!sock)
253 		return error;	/* f_count++ */
254 	pr_debug("atm_tc_change: f_count %ld\n", file_count(sock->file));
255 	if (sock->ops->family != PF_ATMSVC && sock->ops->family != PF_ATMPVC) {
256 		error = -EPROTOTYPE;
257 		goto err_out;
258 	}
259 	/* @@@ should check if the socket is really operational or we'll crash
260 	   on vcc->send */
261 	if (classid) {
262 		if (TC_H_MAJ(classid ^ sch->handle)) {
263 			pr_debug("atm_tc_change: classid mismatch\n");
264 			error = -EINVAL;
265 			goto err_out;
266 		}
267 	} else {
268 		int i;
269 		unsigned long cl;
270 
271 		for (i = 1; i < 0x8000; i++) {
272 			classid = TC_H_MAKE(sch->handle, 0x8000 | i);
273 			cl = atm_tc_find(sch, classid);
274 			if (!cl)
275 				break;
276 		}
277 	}
278 	pr_debug("atm_tc_change: new id %x\n", classid);
279 	flow = kzalloc(sizeof(struct atm_flow_data) + hdr_len, GFP_KERNEL);
280 	pr_debug("atm_tc_change: flow %p\n", flow);
281 	if (!flow) {
282 		error = -ENOBUFS;
283 		goto err_out;
284 	}
285 
286 	error = tcf_block_get(&flow->block, &flow->filter_list, sch,
287 			      extack);
288 	if (error) {
289 		kfree(flow);
290 		goto err_out;
291 	}
292 
293 	flow->q = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops, classid,
294 				    extack);
295 	if (!flow->q)
296 		flow->q = &noop_qdisc;
297 	pr_debug("atm_tc_change: qdisc %p\n", flow->q);
298 	flow->sock = sock;
299 	flow->vcc = ATM_SD(sock);	/* speedup */
300 	flow->vcc->user_back = flow;
301 	pr_debug("atm_tc_change: vcc %p\n", flow->vcc);
302 	flow->old_pop = flow->vcc->pop;
303 	flow->parent = p;
304 	flow->vcc->pop = sch_atm_pop;
305 	flow->common.classid = classid;
306 	flow->ref = 1;
307 	flow->excess = excess;
308 	list_add(&flow->list, &p->link.list);
309 	flow->hdr_len = hdr_len;
310 	if (hdr)
311 		memcpy(flow->hdr, hdr, hdr_len);
312 	else
313 		memcpy(flow->hdr, llc_oui_ip, sizeof(llc_oui_ip));
314 	*arg = (unsigned long)flow;
315 	return 0;
316 err_out:
317 	sockfd_put(sock);
318 	return error;
319 }
320 
atm_tc_delete(struct Qdisc * sch,unsigned long arg)321 static int atm_tc_delete(struct Qdisc *sch, unsigned long arg)
322 {
323 	struct atm_qdisc_data *p = qdisc_priv(sch);
324 	struct atm_flow_data *flow = (struct atm_flow_data *)arg;
325 
326 	pr_debug("atm_tc_delete(sch %p,[qdisc %p],flow %p)\n", sch, p, flow);
327 	if (list_empty(&flow->list))
328 		return -EINVAL;
329 	if (rcu_access_pointer(flow->filter_list) || flow == &p->link)
330 		return -EBUSY;
331 	/*
332 	 * Reference count must be 2: one for "keepalive" (set at class
333 	 * creation), and one for the reference held when calling delete.
334 	 */
335 	if (flow->ref < 2) {
336 		pr_err("atm_tc_delete: flow->ref == %d\n", flow->ref);
337 		return -EINVAL;
338 	}
339 	if (flow->ref > 2)
340 		return -EBUSY;	/* catch references via excess, etc. */
341 	atm_tc_put(sch, arg);
342 	return 0;
343 }
344 
atm_tc_walk(struct Qdisc * sch,struct qdisc_walker * walker)345 static void atm_tc_walk(struct Qdisc *sch, struct qdisc_walker *walker)
346 {
347 	struct atm_qdisc_data *p = qdisc_priv(sch);
348 	struct atm_flow_data *flow;
349 
350 	pr_debug("atm_tc_walk(sch %p,[qdisc %p],walker %p)\n", sch, p, walker);
351 	if (walker->stop)
352 		return;
353 	list_for_each_entry(flow, &p->flows, list) {
354 		if (walker->count >= walker->skip &&
355 		    walker->fn(sch, (unsigned long)flow, walker) < 0) {
356 			walker->stop = 1;
357 			break;
358 		}
359 		walker->count++;
360 	}
361 }
362 
atm_tc_tcf_block(struct Qdisc * sch,unsigned long cl,struct netlink_ext_ack * extack)363 static struct tcf_block *atm_tc_tcf_block(struct Qdisc *sch, unsigned long cl,
364 					  struct netlink_ext_ack *extack)
365 {
366 	struct atm_qdisc_data *p = qdisc_priv(sch);
367 	struct atm_flow_data *flow = (struct atm_flow_data *)cl;
368 
369 	pr_debug("atm_tc_find_tcf(sch %p,[qdisc %p],flow %p)\n", sch, p, flow);
370 	return flow ? flow->block : p->link.block;
371 }
372 
373 /* --------------------------- Qdisc operations ---------------------------- */
374 
atm_tc_enqueue(struct sk_buff * skb,struct Qdisc * sch,struct sk_buff ** to_free)375 static int atm_tc_enqueue(struct sk_buff *skb, struct Qdisc *sch,
376 			  struct sk_buff **to_free)
377 {
378 	struct atm_qdisc_data *p = qdisc_priv(sch);
379 	struct atm_flow_data *flow;
380 	struct tcf_result res;
381 	int result;
382 	int ret = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
383 
384 	pr_debug("atm_tc_enqueue(skb %p,sch %p,[qdisc %p])\n", skb, sch, p);
385 	result = TC_ACT_OK;	/* be nice to gcc */
386 	flow = NULL;
387 	if (TC_H_MAJ(skb->priority) != sch->handle ||
388 	    !(flow = (struct atm_flow_data *)atm_tc_find(sch, skb->priority))) {
389 		struct tcf_proto *fl;
390 
391 		list_for_each_entry(flow, &p->flows, list) {
392 			fl = rcu_dereference_bh(flow->filter_list);
393 			if (fl) {
394 				result = tcf_classify(skb, fl, &res, true);
395 				if (result < 0)
396 					continue;
397 				flow = (struct atm_flow_data *)res.class;
398 				if (!flow)
399 					flow = lookup_flow(sch, res.classid);
400 				goto done;
401 			}
402 		}
403 		flow = NULL;
404 done:
405 		;
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 		case TC_ACT_TRAP:
418 			__qdisc_drop(skb, to_free);
419 			return NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
420 		case TC_ACT_SHOT:
421 			__qdisc_drop(skb, to_free);
422 			goto drop;
423 		case TC_ACT_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, to_free);
434 	if (ret != NET_XMIT_SUCCESS) {
435 drop: __maybe_unused
436 		if (net_xmit_drop_count(ret)) {
437 			qdisc_qstats_drop(sch);
438 			if (flow)
439 				flow->qstats.drops++;
440 		}
441 		return ret;
442 	}
443 	/*
444 	 * Okay, this may seem weird. We pretend we've dropped the packet if
445 	 * it goes via ATM. The reason for this is that the outer qdisc
446 	 * expects to be able to q->dequeue the packet later on if we return
447 	 * success at this place. Also, sch->q.qdisc needs to reflect whether
448 	 * there is a packet egligible for dequeuing or not. Note that the
449 	 * statistics of the outer qdisc are necessarily wrong because of all
450 	 * this. There's currently no correct solution for this.
451 	 */
452 	if (flow == &p->link) {
453 		sch->q.qlen++;
454 		return NET_XMIT_SUCCESS;
455 	}
456 	tasklet_schedule(&p->task);
457 	return NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
458 }
459 
460 /*
461  * Dequeue packets and send them over ATM. Note that we quite deliberately
462  * avoid checking net_device's flow control here, simply because sch_atm
463  * uses its own channels, which have nothing to do with any CLIP/LANE/or
464  * non-ATM interfaces.
465  */
466 
sch_atm_dequeue(unsigned long data)467 static void sch_atm_dequeue(unsigned long data)
468 {
469 	struct Qdisc *sch = (struct Qdisc *)data;
470 	struct atm_qdisc_data *p = qdisc_priv(sch);
471 	struct atm_flow_data *flow;
472 	struct sk_buff *skb;
473 
474 	pr_debug("sch_atm_dequeue(sch %p,[qdisc %p])\n", sch, p);
475 	list_for_each_entry(flow, &p->flows, list) {
476 		if (flow == &p->link)
477 			continue;
478 		/*
479 		 * If traffic is properly shaped, this won't generate nasty
480 		 * little bursts. Otherwise, it may ... (but that's okay)
481 		 */
482 		while ((skb = flow->q->ops->peek(flow->q))) {
483 			if (!atm_may_send(flow->vcc, skb->truesize))
484 				break;
485 
486 			skb = qdisc_dequeue_peeked(flow->q);
487 			if (unlikely(!skb))
488 				break;
489 
490 			qdisc_bstats_update(sch, skb);
491 			bstats_update(&flow->bstats, skb);
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 			refcount_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 
atm_tc_dequeue(struct Qdisc * sch)517 static struct sk_buff *atm_tc_dequeue(struct Qdisc *sch)
518 {
519 	struct atm_qdisc_data *p = qdisc_priv(sch);
520 	struct sk_buff *skb;
521 
522 	pr_debug("atm_tc_dequeue(sch %p,[qdisc %p])\n", sch, p);
523 	tasklet_schedule(&p->task);
524 	skb = qdisc_dequeue_peeked(p->link.q);
525 	if (skb)
526 		sch->q.qlen--;
527 	return skb;
528 }
529 
atm_tc_peek(struct Qdisc * sch)530 static struct sk_buff *atm_tc_peek(struct Qdisc *sch)
531 {
532 	struct atm_qdisc_data *p = qdisc_priv(sch);
533 
534 	pr_debug("atm_tc_peek(sch %p,[qdisc %p])\n", sch, p);
535 
536 	return p->link.q->ops->peek(p->link.q);
537 }
538 
atm_tc_init(struct Qdisc * sch,struct nlattr * opt,struct netlink_ext_ack * extack)539 static int atm_tc_init(struct Qdisc *sch, struct nlattr *opt,
540 		       struct netlink_ext_ack *extack)
541 {
542 	struct atm_qdisc_data *p = qdisc_priv(sch);
543 	int err;
544 
545 	pr_debug("atm_tc_init(sch %p,[qdisc %p],opt %p)\n", sch, p, opt);
546 	INIT_LIST_HEAD(&p->flows);
547 	INIT_LIST_HEAD(&p->link.list);
548 	list_add(&p->link.list, &p->flows);
549 	p->link.q = qdisc_create_dflt(sch->dev_queue,
550 				      &pfifo_qdisc_ops, sch->handle, extack);
551 	if (!p->link.q)
552 		p->link.q = &noop_qdisc;
553 	pr_debug("atm_tc_init: link (%p) qdisc %p\n", &p->link, p->link.q);
554 
555 	err = tcf_block_get(&p->link.block, &p->link.filter_list, sch,
556 			    extack);
557 	if (err)
558 		return err;
559 
560 	p->link.vcc = NULL;
561 	p->link.sock = NULL;
562 	p->link.common.classid = sch->handle;
563 	p->link.ref = 1;
564 	tasklet_init(&p->task, sch_atm_dequeue, (unsigned long)sch);
565 	return 0;
566 }
567 
atm_tc_reset(struct Qdisc * sch)568 static void atm_tc_reset(struct Qdisc *sch)
569 {
570 	struct atm_qdisc_data *p = qdisc_priv(sch);
571 	struct atm_flow_data *flow;
572 
573 	pr_debug("atm_tc_reset(sch %p,[qdisc %p])\n", sch, p);
574 	list_for_each_entry(flow, &p->flows, list)
575 		qdisc_reset(flow->q);
576 	sch->q.qlen = 0;
577 }
578 
atm_tc_destroy(struct Qdisc * sch)579 static void atm_tc_destroy(struct Qdisc *sch)
580 {
581 	struct atm_qdisc_data *p = qdisc_priv(sch);
582 	struct atm_flow_data *flow, *tmp;
583 
584 	pr_debug("atm_tc_destroy(sch %p,[qdisc %p])\n", sch, p);
585 	list_for_each_entry(flow, &p->flows, list) {
586 		tcf_block_put(flow->block);
587 		flow->block = NULL;
588 	}
589 
590 	list_for_each_entry_safe(flow, tmp, &p->flows, list) {
591 		if (flow->ref > 1)
592 			pr_err("atm_destroy: %p->ref = %d\n", flow, flow->ref);
593 		atm_tc_put(sch, (unsigned long)flow);
594 	}
595 	tasklet_kill(&p->task);
596 }
597 
atm_tc_dump_class(struct Qdisc * sch,unsigned long cl,struct sk_buff * skb,struct tcmsg * tcm)598 static int atm_tc_dump_class(struct Qdisc *sch, unsigned long cl,
599 			     struct sk_buff *skb, struct tcmsg *tcm)
600 {
601 	struct atm_qdisc_data *p = qdisc_priv(sch);
602 	struct atm_flow_data *flow = (struct atm_flow_data *)cl;
603 	struct nlattr *nest;
604 
605 	pr_debug("atm_tc_dump_class(sch %p,[qdisc %p],flow %p,skb %p,tcm %p)\n",
606 		sch, p, flow, skb, tcm);
607 	if (list_empty(&flow->list))
608 		return -EINVAL;
609 	tcm->tcm_handle = flow->common.classid;
610 	tcm->tcm_info = flow->q->handle;
611 
612 	nest = nla_nest_start(skb, TCA_OPTIONS);
613 	if (nest == NULL)
614 		goto nla_put_failure;
615 
616 	if (nla_put(skb, TCA_ATM_HDR, flow->hdr_len, flow->hdr))
617 		goto nla_put_failure;
618 	if (flow->vcc) {
619 		struct sockaddr_atmpvc pvc;
620 		int state;
621 
622 		memset(&pvc, 0, sizeof(pvc));
623 		pvc.sap_family = AF_ATMPVC;
624 		pvc.sap_addr.itf = flow->vcc->dev ? flow->vcc->dev->number : -1;
625 		pvc.sap_addr.vpi = flow->vcc->vpi;
626 		pvc.sap_addr.vci = flow->vcc->vci;
627 		if (nla_put(skb, TCA_ATM_ADDR, sizeof(pvc), &pvc))
628 			goto nla_put_failure;
629 		state = ATM_VF2VS(flow->vcc->flags);
630 		if (nla_put_u32(skb, TCA_ATM_STATE, state))
631 			goto nla_put_failure;
632 	}
633 	if (flow->excess) {
634 		if (nla_put_u32(skb, TCA_ATM_EXCESS, flow->common.classid))
635 			goto nla_put_failure;
636 	} else {
637 		if (nla_put_u32(skb, TCA_ATM_EXCESS, 0))
638 			goto nla_put_failure;
639 	}
640 	return nla_nest_end(skb, nest);
641 
642 nla_put_failure:
643 	nla_nest_cancel(skb, nest);
644 	return -1;
645 }
646 static int
atm_tc_dump_class_stats(struct Qdisc * sch,unsigned long arg,struct gnet_dump * d)647 atm_tc_dump_class_stats(struct Qdisc *sch, unsigned long arg,
648 			struct gnet_dump *d)
649 {
650 	struct atm_flow_data *flow = (struct atm_flow_data *)arg;
651 
652 	if (gnet_stats_copy_basic(qdisc_root_sleeping_running(sch),
653 				  d, NULL, &flow->bstats) < 0 ||
654 	    gnet_stats_copy_queue(d, NULL, &flow->qstats, flow->q->q.qlen) < 0)
655 		return -1;
656 
657 	return 0;
658 }
659 
atm_tc_dump(struct Qdisc * sch,struct sk_buff * skb)660 static int atm_tc_dump(struct Qdisc *sch, struct sk_buff *skb)
661 {
662 	return 0;
663 }
664 
665 static const struct Qdisc_class_ops atm_class_ops = {
666 	.graft		= atm_tc_graft,
667 	.leaf		= atm_tc_leaf,
668 	.find		= atm_tc_find,
669 	.change		= atm_tc_change,
670 	.delete		= atm_tc_delete,
671 	.walk		= atm_tc_walk,
672 	.tcf_block	= atm_tc_tcf_block,
673 	.bind_tcf	= atm_tc_bind_filter,
674 	.unbind_tcf	= atm_tc_put,
675 	.dump		= atm_tc_dump_class,
676 	.dump_stats	= atm_tc_dump_class_stats,
677 };
678 
679 static struct Qdisc_ops atm_qdisc_ops __read_mostly = {
680 	.cl_ops		= &atm_class_ops,
681 	.id		= "atm",
682 	.priv_size	= sizeof(struct atm_qdisc_data),
683 	.enqueue	= atm_tc_enqueue,
684 	.dequeue	= atm_tc_dequeue,
685 	.peek		= atm_tc_peek,
686 	.init		= atm_tc_init,
687 	.reset		= atm_tc_reset,
688 	.destroy	= atm_tc_destroy,
689 	.dump		= atm_tc_dump,
690 	.owner		= THIS_MODULE,
691 };
692 
atm_init(void)693 static int __init atm_init(void)
694 {
695 	return register_qdisc(&atm_qdisc_ops);
696 }
697 
atm_exit(void)698 static void __exit atm_exit(void)
699 {
700 	unregister_qdisc(&atm_qdisc_ops);
701 }
702 
703 module_init(atm_init)
704 module_exit(atm_exit)
705 MODULE_LICENSE("GPL");
706