xref: /openbmc/linux/include/net/sch_generic.h (revision 63dc02bd)
1 #ifndef __NET_SCHED_GENERIC_H
2 #define __NET_SCHED_GENERIC_H
3 
4 #include <linux/netdevice.h>
5 #include <linux/types.h>
6 #include <linux/rcupdate.h>
7 #include <linux/pkt_sched.h>
8 #include <linux/pkt_cls.h>
9 #include <net/gen_stats.h>
10 #include <net/rtnetlink.h>
11 
12 struct Qdisc_ops;
13 struct qdisc_walker;
14 struct tcf_walker;
15 struct module;
16 
17 struct qdisc_rate_table {
18 	struct tc_ratespec rate;
19 	u32		data[256];
20 	struct qdisc_rate_table *next;
21 	int		refcnt;
22 };
23 
24 enum qdisc_state_t {
25 	__QDISC_STATE_SCHED,
26 	__QDISC_STATE_DEACTIVATED,
27 	__QDISC_STATE_THROTTLED,
28 };
29 
30 /*
31  * following bits are only changed while qdisc lock is held
32  */
33 enum qdisc___state_t {
34 	__QDISC___STATE_RUNNING = 1,
35 };
36 
37 struct qdisc_size_table {
38 	struct rcu_head		rcu;
39 	struct list_head	list;
40 	struct tc_sizespec	szopts;
41 	int			refcnt;
42 	u16			data[];
43 };
44 
45 struct Qdisc {
46 	int 			(*enqueue)(struct sk_buff *skb, struct Qdisc *dev);
47 	struct sk_buff *	(*dequeue)(struct Qdisc *dev);
48 	unsigned int		flags;
49 #define TCQ_F_BUILTIN		1
50 #define TCQ_F_INGRESS		2
51 #define TCQ_F_CAN_BYPASS	4
52 #define TCQ_F_MQROOT		8
53 #define TCQ_F_WARN_NONWC	(1 << 16)
54 	int			padded;
55 	const struct Qdisc_ops	*ops;
56 	struct qdisc_size_table	__rcu *stab;
57 	struct list_head	list;
58 	u32			handle;
59 	u32			parent;
60 	atomic_t		refcnt;
61 	struct gnet_stats_rate_est	rate_est;
62 	int			(*reshape_fail)(struct sk_buff *skb,
63 					struct Qdisc *q);
64 
65 	void			*u32_node;
66 
67 	/* This field is deprecated, but it is still used by CBQ
68 	 * and it will live until better solution will be invented.
69 	 */
70 	struct Qdisc		*__parent;
71 	struct netdev_queue	*dev_queue;
72 	struct Qdisc		*next_sched;
73 
74 	struct sk_buff		*gso_skb;
75 	/*
76 	 * For performance sake on SMP, we put highly modified fields at the end
77 	 */
78 	unsigned long		state;
79 	struct sk_buff_head	q;
80 	struct gnet_stats_basic_packed bstats;
81 	unsigned int		__state;
82 	struct gnet_stats_queue	qstats;
83 	struct rcu_head		rcu_head;
84 	spinlock_t		busylock;
85 	u32			limit;
86 };
87 
88 static inline bool qdisc_is_running(const struct Qdisc *qdisc)
89 {
90 	return (qdisc->__state & __QDISC___STATE_RUNNING) ? true : false;
91 }
92 
93 static inline bool qdisc_run_begin(struct Qdisc *qdisc)
94 {
95 	if (qdisc_is_running(qdisc))
96 		return false;
97 	qdisc->__state |= __QDISC___STATE_RUNNING;
98 	return true;
99 }
100 
101 static inline void qdisc_run_end(struct Qdisc *qdisc)
102 {
103 	qdisc->__state &= ~__QDISC___STATE_RUNNING;
104 }
105 
106 static inline bool qdisc_is_throttled(const struct Qdisc *qdisc)
107 {
108 	return test_bit(__QDISC_STATE_THROTTLED, &qdisc->state) ? true : false;
109 }
110 
111 static inline void qdisc_throttled(struct Qdisc *qdisc)
112 {
113 	set_bit(__QDISC_STATE_THROTTLED, &qdisc->state);
114 }
115 
116 static inline void qdisc_unthrottled(struct Qdisc *qdisc)
117 {
118 	clear_bit(__QDISC_STATE_THROTTLED, &qdisc->state);
119 }
120 
121 struct Qdisc_class_ops {
122 	/* Child qdisc manipulation */
123 	struct netdev_queue *	(*select_queue)(struct Qdisc *, struct tcmsg *);
124 	int			(*graft)(struct Qdisc *, unsigned long cl,
125 					struct Qdisc *, struct Qdisc **);
126 	struct Qdisc *		(*leaf)(struct Qdisc *, unsigned long cl);
127 	void			(*qlen_notify)(struct Qdisc *, unsigned long);
128 
129 	/* Class manipulation routines */
130 	unsigned long		(*get)(struct Qdisc *, u32 classid);
131 	void			(*put)(struct Qdisc *, unsigned long);
132 	int			(*change)(struct Qdisc *, u32, u32,
133 					struct nlattr **, unsigned long *);
134 	int			(*delete)(struct Qdisc *, unsigned long);
135 	void			(*walk)(struct Qdisc *, struct qdisc_walker * arg);
136 
137 	/* Filter manipulation */
138 	struct tcf_proto **	(*tcf_chain)(struct Qdisc *, unsigned long);
139 	unsigned long		(*bind_tcf)(struct Qdisc *, unsigned long,
140 					u32 classid);
141 	void			(*unbind_tcf)(struct Qdisc *, unsigned long);
142 
143 	/* rtnetlink specific */
144 	int			(*dump)(struct Qdisc *, unsigned long,
145 					struct sk_buff *skb, struct tcmsg*);
146 	int			(*dump_stats)(struct Qdisc *, unsigned long,
147 					struct gnet_dump *);
148 };
149 
150 struct Qdisc_ops {
151 	struct Qdisc_ops	*next;
152 	const struct Qdisc_class_ops	*cl_ops;
153 	char			id[IFNAMSIZ];
154 	int			priv_size;
155 
156 	int 			(*enqueue)(struct sk_buff *, struct Qdisc *);
157 	struct sk_buff *	(*dequeue)(struct Qdisc *);
158 	struct sk_buff *	(*peek)(struct Qdisc *);
159 	unsigned int		(*drop)(struct Qdisc *);
160 
161 	int			(*init)(struct Qdisc *, struct nlattr *arg);
162 	void			(*reset)(struct Qdisc *);
163 	void			(*destroy)(struct Qdisc *);
164 	int			(*change)(struct Qdisc *, struct nlattr *arg);
165 	void			(*attach)(struct Qdisc *);
166 
167 	int			(*dump)(struct Qdisc *, struct sk_buff *);
168 	int			(*dump_stats)(struct Qdisc *, struct gnet_dump *);
169 
170 	struct module		*owner;
171 };
172 
173 
174 struct tcf_result {
175 	unsigned long	class;
176 	u32		classid;
177 };
178 
179 struct tcf_proto_ops {
180 	struct tcf_proto_ops	*next;
181 	char			kind[IFNAMSIZ];
182 
183 	int			(*classify)(struct sk_buff *,
184 					    const struct tcf_proto *,
185 					    struct tcf_result *);
186 	int			(*init)(struct tcf_proto*);
187 	void			(*destroy)(struct tcf_proto*);
188 
189 	unsigned long		(*get)(struct tcf_proto*, u32 handle);
190 	void			(*put)(struct tcf_proto*, unsigned long);
191 	int			(*change)(struct tcf_proto*, unsigned long,
192 					u32 handle, struct nlattr **,
193 					unsigned long *);
194 	int			(*delete)(struct tcf_proto*, unsigned long);
195 	void			(*walk)(struct tcf_proto*, struct tcf_walker *arg);
196 
197 	/* rtnetlink specific */
198 	int			(*dump)(struct tcf_proto*, unsigned long,
199 					struct sk_buff *skb, struct tcmsg*);
200 
201 	struct module		*owner;
202 };
203 
204 struct tcf_proto {
205 	/* Fast access part */
206 	struct tcf_proto	*next;
207 	void			*root;
208 	int			(*classify)(struct sk_buff *,
209 					    const struct tcf_proto *,
210 					    struct tcf_result *);
211 	__be16			protocol;
212 
213 	/* All the rest */
214 	u32			prio;
215 	u32			classid;
216 	struct Qdisc		*q;
217 	void			*data;
218 	const struct tcf_proto_ops	*ops;
219 };
220 
221 struct qdisc_skb_cb {
222 	unsigned int		pkt_len;
223 	unsigned char		data[24];
224 };
225 
226 static inline void qdisc_cb_private_validate(const struct sk_buff *skb, int sz)
227 {
228 	struct qdisc_skb_cb *qcb;
229 	BUILD_BUG_ON(sizeof(skb->cb) < sizeof(unsigned int) + sz);
230 	BUILD_BUG_ON(sizeof(qcb->data) < sz);
231 }
232 
233 static inline int qdisc_qlen(const struct Qdisc *q)
234 {
235 	return q->q.qlen;
236 }
237 
238 static inline struct qdisc_skb_cb *qdisc_skb_cb(const struct sk_buff *skb)
239 {
240 	return (struct qdisc_skb_cb *)skb->cb;
241 }
242 
243 static inline spinlock_t *qdisc_lock(struct Qdisc *qdisc)
244 {
245 	return &qdisc->q.lock;
246 }
247 
248 static inline struct Qdisc *qdisc_root(const struct Qdisc *qdisc)
249 {
250 	return qdisc->dev_queue->qdisc;
251 }
252 
253 static inline struct Qdisc *qdisc_root_sleeping(const struct Qdisc *qdisc)
254 {
255 	return qdisc->dev_queue->qdisc_sleeping;
256 }
257 
258 /* The qdisc root lock is a mechanism by which to top level
259  * of a qdisc tree can be locked from any qdisc node in the
260  * forest.  This allows changing the configuration of some
261  * aspect of the qdisc tree while blocking out asynchronous
262  * qdisc access in the packet processing paths.
263  *
264  * It is only legal to do this when the root will not change
265  * on us.  Otherwise we'll potentially lock the wrong qdisc
266  * root.  This is enforced by holding the RTNL semaphore, which
267  * all users of this lock accessor must do.
268  */
269 static inline spinlock_t *qdisc_root_lock(const struct Qdisc *qdisc)
270 {
271 	struct Qdisc *root = qdisc_root(qdisc);
272 
273 	ASSERT_RTNL();
274 	return qdisc_lock(root);
275 }
276 
277 static inline spinlock_t *qdisc_root_sleeping_lock(const struct Qdisc *qdisc)
278 {
279 	struct Qdisc *root = qdisc_root_sleeping(qdisc);
280 
281 	ASSERT_RTNL();
282 	return qdisc_lock(root);
283 }
284 
285 static inline struct net_device *qdisc_dev(const struct Qdisc *qdisc)
286 {
287 	return qdisc->dev_queue->dev;
288 }
289 
290 static inline void sch_tree_lock(const struct Qdisc *q)
291 {
292 	spin_lock_bh(qdisc_root_sleeping_lock(q));
293 }
294 
295 static inline void sch_tree_unlock(const struct Qdisc *q)
296 {
297 	spin_unlock_bh(qdisc_root_sleeping_lock(q));
298 }
299 
300 #define tcf_tree_lock(tp)	sch_tree_lock((tp)->q)
301 #define tcf_tree_unlock(tp)	sch_tree_unlock((tp)->q)
302 
303 extern struct Qdisc noop_qdisc;
304 extern struct Qdisc_ops noop_qdisc_ops;
305 extern struct Qdisc_ops pfifo_fast_ops;
306 extern struct Qdisc_ops mq_qdisc_ops;
307 
308 struct Qdisc_class_common {
309 	u32			classid;
310 	struct hlist_node	hnode;
311 };
312 
313 struct Qdisc_class_hash {
314 	struct hlist_head	*hash;
315 	unsigned int		hashsize;
316 	unsigned int		hashmask;
317 	unsigned int		hashelems;
318 };
319 
320 static inline unsigned int qdisc_class_hash(u32 id, u32 mask)
321 {
322 	id ^= id >> 8;
323 	id ^= id >> 4;
324 	return id & mask;
325 }
326 
327 static inline struct Qdisc_class_common *
328 qdisc_class_find(const struct Qdisc_class_hash *hash, u32 id)
329 {
330 	struct Qdisc_class_common *cl;
331 	struct hlist_node *n;
332 	unsigned int h;
333 
334 	h = qdisc_class_hash(id, hash->hashmask);
335 	hlist_for_each_entry(cl, n, &hash->hash[h], hnode) {
336 		if (cl->classid == id)
337 			return cl;
338 	}
339 	return NULL;
340 }
341 
342 extern int qdisc_class_hash_init(struct Qdisc_class_hash *);
343 extern void qdisc_class_hash_insert(struct Qdisc_class_hash *, struct Qdisc_class_common *);
344 extern void qdisc_class_hash_remove(struct Qdisc_class_hash *, struct Qdisc_class_common *);
345 extern void qdisc_class_hash_grow(struct Qdisc *, struct Qdisc_class_hash *);
346 extern void qdisc_class_hash_destroy(struct Qdisc_class_hash *);
347 
348 extern void dev_init_scheduler(struct net_device *dev);
349 extern void dev_shutdown(struct net_device *dev);
350 extern void dev_activate(struct net_device *dev);
351 extern void dev_deactivate(struct net_device *dev);
352 extern void dev_deactivate_many(struct list_head *head);
353 extern struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue,
354 				     struct Qdisc *qdisc);
355 extern void qdisc_reset(struct Qdisc *qdisc);
356 extern void qdisc_destroy(struct Qdisc *qdisc);
357 extern void qdisc_tree_decrease_qlen(struct Qdisc *qdisc, unsigned int n);
358 extern struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
359 				 struct Qdisc_ops *ops);
360 extern struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue,
361 				       struct Qdisc_ops *ops, u32 parentid);
362 extern void __qdisc_calculate_pkt_len(struct sk_buff *skb,
363 				      const struct qdisc_size_table *stab);
364 extern void tcf_destroy(struct tcf_proto *tp);
365 extern void tcf_destroy_chain(struct tcf_proto **fl);
366 
367 /* Reset all TX qdiscs greater then index of a device.  */
368 static inline void qdisc_reset_all_tx_gt(struct net_device *dev, unsigned int i)
369 {
370 	struct Qdisc *qdisc;
371 
372 	for (; i < dev->num_tx_queues; i++) {
373 		qdisc = netdev_get_tx_queue(dev, i)->qdisc;
374 		if (qdisc) {
375 			spin_lock_bh(qdisc_lock(qdisc));
376 			qdisc_reset(qdisc);
377 			spin_unlock_bh(qdisc_lock(qdisc));
378 		}
379 	}
380 }
381 
382 static inline void qdisc_reset_all_tx(struct net_device *dev)
383 {
384 	qdisc_reset_all_tx_gt(dev, 0);
385 }
386 
387 /* Are all TX queues of the device empty?  */
388 static inline bool qdisc_all_tx_empty(const struct net_device *dev)
389 {
390 	unsigned int i;
391 	for (i = 0; i < dev->num_tx_queues; i++) {
392 		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
393 		const struct Qdisc *q = txq->qdisc;
394 
395 		if (q->q.qlen)
396 			return false;
397 	}
398 	return true;
399 }
400 
401 /* Are any of the TX qdiscs changing?  */
402 static inline bool qdisc_tx_changing(const struct net_device *dev)
403 {
404 	unsigned int i;
405 	for (i = 0; i < dev->num_tx_queues; i++) {
406 		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
407 		if (txq->qdisc != txq->qdisc_sleeping)
408 			return true;
409 	}
410 	return false;
411 }
412 
413 /* Is the device using the noop qdisc on all queues?  */
414 static inline bool qdisc_tx_is_noop(const struct net_device *dev)
415 {
416 	unsigned int i;
417 	for (i = 0; i < dev->num_tx_queues; i++) {
418 		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
419 		if (txq->qdisc != &noop_qdisc)
420 			return false;
421 	}
422 	return true;
423 }
424 
425 static inline unsigned int qdisc_pkt_len(const struct sk_buff *skb)
426 {
427 	return qdisc_skb_cb(skb)->pkt_len;
428 }
429 
430 /* additional qdisc xmit flags (NET_XMIT_MASK in linux/netdevice.h) */
431 enum net_xmit_qdisc_t {
432 	__NET_XMIT_STOLEN = 0x00010000,
433 	__NET_XMIT_BYPASS = 0x00020000,
434 };
435 
436 #ifdef CONFIG_NET_CLS_ACT
437 #define net_xmit_drop_count(e)	((e) & __NET_XMIT_STOLEN ? 0 : 1)
438 #else
439 #define net_xmit_drop_count(e)	(1)
440 #endif
441 
442 static inline void qdisc_calculate_pkt_len(struct sk_buff *skb,
443 					   const struct Qdisc *sch)
444 {
445 #ifdef CONFIG_NET_SCHED
446 	struct qdisc_size_table *stab = rcu_dereference_bh(sch->stab);
447 
448 	if (stab)
449 		__qdisc_calculate_pkt_len(skb, stab);
450 #endif
451 }
452 
453 static inline int qdisc_enqueue(struct sk_buff *skb, struct Qdisc *sch)
454 {
455 	qdisc_calculate_pkt_len(skb, sch);
456 	return sch->enqueue(skb, sch);
457 }
458 
459 static inline int qdisc_enqueue_root(struct sk_buff *skb, struct Qdisc *sch)
460 {
461 	qdisc_skb_cb(skb)->pkt_len = skb->len;
462 	return qdisc_enqueue(skb, sch) & NET_XMIT_MASK;
463 }
464 
465 
466 static inline void bstats_update(struct gnet_stats_basic_packed *bstats,
467 				 const struct sk_buff *skb)
468 {
469 	bstats->bytes += qdisc_pkt_len(skb);
470 	bstats->packets += skb_is_gso(skb) ? skb_shinfo(skb)->gso_segs : 1;
471 }
472 
473 static inline void qdisc_bstats_update(struct Qdisc *sch,
474 				       const struct sk_buff *skb)
475 {
476 	bstats_update(&sch->bstats, skb);
477 }
478 
479 static inline int __qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch,
480 				       struct sk_buff_head *list)
481 {
482 	__skb_queue_tail(list, skb);
483 	sch->qstats.backlog += qdisc_pkt_len(skb);
484 
485 	return NET_XMIT_SUCCESS;
486 }
487 
488 static inline int qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch)
489 {
490 	return __qdisc_enqueue_tail(skb, sch, &sch->q);
491 }
492 
493 static inline struct sk_buff *__qdisc_dequeue_head(struct Qdisc *sch,
494 						   struct sk_buff_head *list)
495 {
496 	struct sk_buff *skb = __skb_dequeue(list);
497 
498 	if (likely(skb != NULL)) {
499 		sch->qstats.backlog -= qdisc_pkt_len(skb);
500 		qdisc_bstats_update(sch, skb);
501 	}
502 
503 	return skb;
504 }
505 
506 static inline struct sk_buff *qdisc_dequeue_head(struct Qdisc *sch)
507 {
508 	return __qdisc_dequeue_head(sch, &sch->q);
509 }
510 
511 static inline unsigned int __qdisc_queue_drop_head(struct Qdisc *sch,
512 					      struct sk_buff_head *list)
513 {
514 	struct sk_buff *skb = __skb_dequeue(list);
515 
516 	if (likely(skb != NULL)) {
517 		unsigned int len = qdisc_pkt_len(skb);
518 		sch->qstats.backlog -= len;
519 		kfree_skb(skb);
520 		return len;
521 	}
522 
523 	return 0;
524 }
525 
526 static inline unsigned int qdisc_queue_drop_head(struct Qdisc *sch)
527 {
528 	return __qdisc_queue_drop_head(sch, &sch->q);
529 }
530 
531 static inline struct sk_buff *__qdisc_dequeue_tail(struct Qdisc *sch,
532 						   struct sk_buff_head *list)
533 {
534 	struct sk_buff *skb = __skb_dequeue_tail(list);
535 
536 	if (likely(skb != NULL))
537 		sch->qstats.backlog -= qdisc_pkt_len(skb);
538 
539 	return skb;
540 }
541 
542 static inline struct sk_buff *qdisc_dequeue_tail(struct Qdisc *sch)
543 {
544 	return __qdisc_dequeue_tail(sch, &sch->q);
545 }
546 
547 static inline struct sk_buff *qdisc_peek_head(struct Qdisc *sch)
548 {
549 	return skb_peek(&sch->q);
550 }
551 
552 /* generic pseudo peek method for non-work-conserving qdisc */
553 static inline struct sk_buff *qdisc_peek_dequeued(struct Qdisc *sch)
554 {
555 	/* we can reuse ->gso_skb because peek isn't called for root qdiscs */
556 	if (!sch->gso_skb) {
557 		sch->gso_skb = sch->dequeue(sch);
558 		if (sch->gso_skb)
559 			/* it's still part of the queue */
560 			sch->q.qlen++;
561 	}
562 
563 	return sch->gso_skb;
564 }
565 
566 /* use instead of qdisc->dequeue() for all qdiscs queried with ->peek() */
567 static inline struct sk_buff *qdisc_dequeue_peeked(struct Qdisc *sch)
568 {
569 	struct sk_buff *skb = sch->gso_skb;
570 
571 	if (skb) {
572 		sch->gso_skb = NULL;
573 		sch->q.qlen--;
574 	} else {
575 		skb = sch->dequeue(sch);
576 	}
577 
578 	return skb;
579 }
580 
581 static inline void __qdisc_reset_queue(struct Qdisc *sch,
582 				       struct sk_buff_head *list)
583 {
584 	/*
585 	 * We do not know the backlog in bytes of this list, it
586 	 * is up to the caller to correct it
587 	 */
588 	__skb_queue_purge(list);
589 }
590 
591 static inline void qdisc_reset_queue(struct Qdisc *sch)
592 {
593 	__qdisc_reset_queue(sch, &sch->q);
594 	sch->qstats.backlog = 0;
595 }
596 
597 static inline unsigned int __qdisc_queue_drop(struct Qdisc *sch,
598 					      struct sk_buff_head *list)
599 {
600 	struct sk_buff *skb = __qdisc_dequeue_tail(sch, list);
601 
602 	if (likely(skb != NULL)) {
603 		unsigned int len = qdisc_pkt_len(skb);
604 		kfree_skb(skb);
605 		return len;
606 	}
607 
608 	return 0;
609 }
610 
611 static inline unsigned int qdisc_queue_drop(struct Qdisc *sch)
612 {
613 	return __qdisc_queue_drop(sch, &sch->q);
614 }
615 
616 static inline int qdisc_drop(struct sk_buff *skb, struct Qdisc *sch)
617 {
618 	kfree_skb(skb);
619 	sch->qstats.drops++;
620 
621 	return NET_XMIT_DROP;
622 }
623 
624 static inline int qdisc_reshape_fail(struct sk_buff *skb, struct Qdisc *sch)
625 {
626 	sch->qstats.drops++;
627 
628 #ifdef CONFIG_NET_CLS_ACT
629 	if (sch->reshape_fail == NULL || sch->reshape_fail(skb, sch))
630 		goto drop;
631 
632 	return NET_XMIT_SUCCESS;
633 
634 drop:
635 #endif
636 	kfree_skb(skb);
637 	return NET_XMIT_DROP;
638 }
639 
640 /* Length to Time (L2T) lookup in a qdisc_rate_table, to determine how
641    long it will take to send a packet given its size.
642  */
643 static inline u32 qdisc_l2t(struct qdisc_rate_table* rtab, unsigned int pktlen)
644 {
645 	int slot = pktlen + rtab->rate.cell_align + rtab->rate.overhead;
646 	if (slot < 0)
647 		slot = 0;
648 	slot >>= rtab->rate.cell_log;
649 	if (slot > 255)
650 		return rtab->data[255]*(slot >> 8) + rtab->data[slot & 0xFF];
651 	return rtab->data[slot];
652 }
653 
654 #ifdef CONFIG_NET_CLS_ACT
655 static inline struct sk_buff *skb_act_clone(struct sk_buff *skb, gfp_t gfp_mask,
656 					    int action)
657 {
658 	struct sk_buff *n;
659 
660 	n = skb_clone(skb, gfp_mask);
661 
662 	if (n) {
663 		n->tc_verd = SET_TC_VERD(n->tc_verd, 0);
664 		n->tc_verd = CLR_TC_OK2MUNGE(n->tc_verd);
665 		n->tc_verd = CLR_TC_MUNGED(n->tc_verd);
666 	}
667 	return n;
668 }
669 #endif
670 
671 #endif
672