sch_generic.h 16.2 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664
#ifndef __NET_SCHED_GENERIC_H
#define __NET_SCHED_GENERIC_H

#include <linux/netdevice.h>
#include <linux/types.h>
#include <linux/rcupdate.h>
#include <linux/pkt_sched.h>
#include <linux/pkt_cls.h>
#include <net/gen_stats.h>
#include <net/rtnetlink.h>

struct Qdisc_ops;
struct qdisc_walker;
struct tcf_walker;
struct module;

struct qdisc_rate_table {
	struct tc_ratespec rate;
	u32		data[256];
	struct qdisc_rate_table *next;
	int		refcnt;
};

enum qdisc_state_t {
	__QDISC_STATE_SCHED,
	__QDISC_STATE_DEACTIVATED,
	__QDISC_STATE_THROTTLED,
};

/*
 * following bits are only changed while qdisc lock is held
 */
enum qdisc___state_t {
	__QDISC___STATE_RUNNING = 1,
};

struct qdisc_size_table {
	struct rcu_head		rcu;
	struct list_head	list;
	struct tc_sizespec	szopts;
	int			refcnt;
	u16			data[];
};

struct Qdisc {
	int 			(*enqueue)(struct sk_buff *skb, struct Qdisc *dev);
	struct sk_buff *	(*dequeue)(struct Qdisc *dev);
	unsigned int		flags;
#define TCQ_F_BUILTIN		1
#define TCQ_F_INGRESS		2
#define TCQ_F_CAN_BYPASS	4
#define TCQ_F_MQROOT		8
#define TCQ_F_WARN_NONWC	(1 << 16)
	int			padded;
	const struct Qdisc_ops	*ops;
	struct qdisc_size_table	__rcu *stab;
	struct list_head	list;
	u32			handle;
	u32			parent;
	atomic_t		refcnt;
	struct gnet_stats_rate_est	rate_est;
	int			(*reshape_fail)(struct sk_buff *skb,
					struct Qdisc *q);

	void			*u32_node;

	/* This field is deprecated, but it is still used by CBQ
	 * and it will live until better solution will be invented.
	 */
	struct Qdisc		*__parent;
	struct netdev_queue	*dev_queue;
	struct Qdisc		*next_sched;

	struct sk_buff		*gso_skb;
	/*
	 * For performance sake on SMP, we put highly modified fields at the end
	 */
	unsigned long		state;
	struct sk_buff_head	q;
	struct gnet_stats_basic_packed bstats;
	unsigned int		__state;
	struct gnet_stats_queue	qstats;
	struct rcu_head		rcu_head;
	spinlock_t		busylock;
	u32			limit;
};

static inline bool qdisc_is_running(const struct Qdisc *qdisc)
{
	return (qdisc->__state & __QDISC___STATE_RUNNING) ? true : false;
}

static inline bool qdisc_run_begin(struct Qdisc *qdisc)
{
	if (qdisc_is_running(qdisc))
		return false;
	qdisc->__state |= __QDISC___STATE_RUNNING;
	return true;
}

static inline void qdisc_run_end(struct Qdisc *qdisc)
{
	qdisc->__state &= ~__QDISC___STATE_RUNNING;
}

static inline bool qdisc_is_throttled(const struct Qdisc *qdisc)
{
	return test_bit(__QDISC_STATE_THROTTLED, &qdisc->state) ? true : false;
}

static inline void qdisc_throttled(struct Qdisc *qdisc)
{
	set_bit(__QDISC_STATE_THROTTLED, &qdisc->state);
}

static inline void qdisc_unthrottled(struct Qdisc *qdisc)
{
	clear_bit(__QDISC_STATE_THROTTLED, &qdisc->state);
}

struct Qdisc_class_ops {
	/* Child qdisc manipulation */
	struct netdev_queue *	(*select_queue)(struct Qdisc *, struct tcmsg *);
	int			(*graft)(struct Qdisc *, unsigned long cl,
					struct Qdisc *, struct Qdisc **);
	struct Qdisc *		(*leaf)(struct Qdisc *, unsigned long cl);
	void			(*qlen_notify)(struct Qdisc *, unsigned long);

	/* Class manipulation routines */
	unsigned long		(*get)(struct Qdisc *, u32 classid);
	void			(*put)(struct Qdisc *, unsigned long);
	int			(*change)(struct Qdisc *, u32, u32,
					struct nlattr **, unsigned long *);
	int			(*delete)(struct Qdisc *, unsigned long);
	void			(*walk)(struct Qdisc *, struct qdisc_walker * arg);

	/* Filter manipulation */
	struct tcf_proto **	(*tcf_chain)(struct Qdisc *, unsigned long);
	unsigned long		(*bind_tcf)(struct Qdisc *, unsigned long,
					u32 classid);
	void			(*unbind_tcf)(struct Qdisc *, unsigned long);

	/* rtnetlink specific */
	int			(*dump)(struct Qdisc *, unsigned long,
					struct sk_buff *skb, struct tcmsg*);
	int			(*dump_stats)(struct Qdisc *, unsigned long,
					struct gnet_dump *);
};

struct Qdisc_ops {
	struct Qdisc_ops	*next;
	const struct Qdisc_class_ops	*cl_ops;
	char			id[IFNAMSIZ];
	int			priv_size;

	int 			(*enqueue)(struct sk_buff *, struct Qdisc *);
	struct sk_buff *	(*dequeue)(struct Qdisc *);
	struct sk_buff *	(*peek)(struct Qdisc *);
	unsigned int		(*drop)(struct Qdisc *);

	int			(*init)(struct Qdisc *, struct nlattr *arg);
	void			(*reset)(struct Qdisc *);
	void			(*destroy)(struct Qdisc *);
	int			(*change)(struct Qdisc *, struct nlattr *arg);
	void			(*attach)(struct Qdisc *);

	int			(*dump)(struct Qdisc *, struct sk_buff *);
	int			(*dump_stats)(struct Qdisc *, struct gnet_dump *);

	struct module		*owner;
};


struct tcf_result {
	unsigned long	class;
	u32		classid;
};

struct tcf_proto_ops {
	struct tcf_proto_ops	*next;
	char			kind[IFNAMSIZ];

	int			(*classify)(struct sk_buff *,
					    const struct tcf_proto *,
					    struct tcf_result *);
	int			(*init)(struct tcf_proto*);
	void			(*destroy)(struct tcf_proto*);

	unsigned long		(*get)(struct tcf_proto*, u32 handle);
	void			(*put)(struct tcf_proto*, unsigned long);
	int			(*change)(struct tcf_proto*, unsigned long,
					u32 handle, struct nlattr **,
					unsigned long *);
	int			(*delete)(struct tcf_proto*, unsigned long);
	void			(*walk)(struct tcf_proto*, struct tcf_walker *arg);

	/* rtnetlink specific */
	int			(*dump)(struct tcf_proto*, unsigned long,
					struct sk_buff *skb, struct tcmsg*);

	struct module		*owner;
};

struct tcf_proto {
	/* Fast access part */
	struct tcf_proto	*next;
	void			*root;
	int			(*classify)(struct sk_buff *,
					    const struct tcf_proto *,
					    struct tcf_result *);
	__be16			protocol;

	/* All the rest */
	u32			prio;
	u32			classid;
	struct Qdisc		*q;
	void			*data;
	const struct tcf_proto_ops	*ops;
};

struct qdisc_skb_cb {
	unsigned int		pkt_len;
	long			data[];
};

static inline int qdisc_qlen(const struct Qdisc *q)
{
	return q->q.qlen;
}

static inline struct qdisc_skb_cb *qdisc_skb_cb(const struct sk_buff *skb)
{
	return (struct qdisc_skb_cb *)skb->cb;
}

static inline spinlock_t *qdisc_lock(struct Qdisc *qdisc)
{
	return &qdisc->q.lock;
}

static inline struct Qdisc *qdisc_root(const struct Qdisc *qdisc)
{
	return qdisc->dev_queue->qdisc;
}

static inline struct Qdisc *qdisc_root_sleeping(const struct Qdisc *qdisc)
{
	return qdisc->dev_queue->qdisc_sleeping;
}

/* The qdisc root lock is a mechanism by which to top level
 * of a qdisc tree can be locked from any qdisc node in the
 * forest.  This allows changing the configuration of some
 * aspect of the qdisc tree while blocking out asynchronous
 * qdisc access in the packet processing paths.
 *
 * It is only legal to do this when the root will not change
 * on us.  Otherwise we'll potentially lock the wrong qdisc
 * root.  This is enforced by holding the RTNL semaphore, which
 * all users of this lock accessor must do.
 */
static inline spinlock_t *qdisc_root_lock(const struct Qdisc *qdisc)
{
	struct Qdisc *root = qdisc_root(qdisc);

	ASSERT_RTNL();
	return qdisc_lock(root);
}

static inline spinlock_t *qdisc_root_sleeping_lock(const struct Qdisc *qdisc)
{
	struct Qdisc *root = qdisc_root_sleeping(qdisc);

	ASSERT_RTNL();
	return qdisc_lock(root);
}

static inline struct net_device *qdisc_dev(const struct Qdisc *qdisc)
{
	return qdisc->dev_queue->dev;
}

static inline void sch_tree_lock(const struct Qdisc *q)
{
	spin_lock_bh(qdisc_root_sleeping_lock(q));
}

static inline void sch_tree_unlock(const struct Qdisc *q)
{
	spin_unlock_bh(qdisc_root_sleeping_lock(q));
}

#define tcf_tree_lock(tp)	sch_tree_lock((tp)->q)
#define tcf_tree_unlock(tp)	sch_tree_unlock((tp)->q)

extern struct Qdisc noop_qdisc;
extern struct Qdisc_ops noop_qdisc_ops;
extern struct Qdisc_ops pfifo_fast_ops;
extern struct Qdisc_ops mq_qdisc_ops;

struct Qdisc_class_common {
	u32			classid;
	struct hlist_node	hnode;
};

struct Qdisc_class_hash {
	struct hlist_head	*hash;
	unsigned int		hashsize;
	unsigned int		hashmask;
	unsigned int		hashelems;
};

static inline unsigned int qdisc_class_hash(u32 id, u32 mask)
{
	id ^= id >> 8;
	id ^= id >> 4;
	return id & mask;
}

static inline struct Qdisc_class_common *
qdisc_class_find(const struct Qdisc_class_hash *hash, u32 id)
{
	struct Qdisc_class_common *cl;
	struct hlist_node *n;
	unsigned int h;

	h = qdisc_class_hash(id, hash->hashmask);
	hlist_for_each_entry(cl, n, &hash->hash[h], hnode) {
		if (cl->classid == id)
			return cl;
	}
	return NULL;
}

extern int qdisc_class_hash_init(struct Qdisc_class_hash *);
extern void qdisc_class_hash_insert(struct Qdisc_class_hash *, struct Qdisc_class_common *);
extern void qdisc_class_hash_remove(struct Qdisc_class_hash *, struct Qdisc_class_common *);
extern void qdisc_class_hash_grow(struct Qdisc *, struct Qdisc_class_hash *);
extern void qdisc_class_hash_destroy(struct Qdisc_class_hash *);

extern void dev_init_scheduler(struct net_device *dev);
extern void dev_shutdown(struct net_device *dev);
extern void dev_activate(struct net_device *dev);
extern void dev_deactivate(struct net_device *dev);
extern void dev_deactivate_many(struct list_head *head);
extern struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue,
				     struct Qdisc *qdisc);
extern void qdisc_reset(struct Qdisc *qdisc);
extern void qdisc_destroy(struct Qdisc *qdisc);
extern void qdisc_tree_decrease_qlen(struct Qdisc *qdisc, unsigned int n);
extern struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
				 struct Qdisc_ops *ops);
extern struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue,
				       struct Qdisc_ops *ops, u32 parentid);
extern void __qdisc_calculate_pkt_len(struct sk_buff *skb,
				      const struct qdisc_size_table *stab);
extern void tcf_destroy(struct tcf_proto *tp);
extern void tcf_destroy_chain(struct tcf_proto **fl);

/* Reset all TX qdiscs greater then index of a device.  */
static inline void qdisc_reset_all_tx_gt(struct net_device *dev, unsigned int i)
{
	struct Qdisc *qdisc;

	for (; i < dev->num_tx_queues; i++) {
		qdisc = netdev_get_tx_queue(dev, i)->qdisc;
		if (qdisc) {
			spin_lock_bh(qdisc_lock(qdisc));
			qdisc_reset(qdisc);
			spin_unlock_bh(qdisc_lock(qdisc));
		}
	}
}

static inline void qdisc_reset_all_tx(struct net_device *dev)
{
	qdisc_reset_all_tx_gt(dev, 0);
}

/* Are all TX queues of the device empty?  */
static inline bool qdisc_all_tx_empty(const struct net_device *dev)
{
	unsigned int i;
	for (i = 0; i < dev->num_tx_queues; i++) {
		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
		const struct Qdisc *q = txq->qdisc;

		if (q->q.qlen)
			return false;
	}
	return true;
}

/* Are any of the TX qdiscs changing?  */
static inline bool qdisc_tx_changing(const struct net_device *dev)
{
	unsigned int i;
	for (i = 0; i < dev->num_tx_queues; i++) {
		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
		if (txq->qdisc != txq->qdisc_sleeping)
			return true;
	}
	return false;
}

/* Is the device using the noop qdisc on all queues?  */
static inline bool qdisc_tx_is_noop(const struct net_device *dev)
{
	unsigned int i;
	for (i = 0; i < dev->num_tx_queues; i++) {
		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
		if (txq->qdisc != &noop_qdisc)
			return false;
	}
	return true;
}

static inline unsigned int qdisc_pkt_len(const struct sk_buff *skb)
{
	return qdisc_skb_cb(skb)->pkt_len;
}

/* additional qdisc xmit flags (NET_XMIT_MASK in linux/netdevice.h) */
enum net_xmit_qdisc_t {
	__NET_XMIT_STOLEN = 0x00010000,
	__NET_XMIT_BYPASS = 0x00020000,
};

#ifdef CONFIG_NET_CLS_ACT
#define net_xmit_drop_count(e)	((e) & __NET_XMIT_STOLEN ? 0 : 1)
#else
#define net_xmit_drop_count(e)	(1)
#endif

static inline void qdisc_calculate_pkt_len(struct sk_buff *skb,
					   const struct Qdisc *sch)
{
#ifdef CONFIG_NET_SCHED
	struct qdisc_size_table *stab = rcu_dereference_bh(sch->stab);

	if (stab)
		__qdisc_calculate_pkt_len(skb, stab);
#endif
}

static inline int qdisc_enqueue(struct sk_buff *skb, struct Qdisc *sch)
{
	qdisc_calculate_pkt_len(skb, sch);
	return sch->enqueue(skb, sch);
}

static inline int qdisc_enqueue_root(struct sk_buff *skb, struct Qdisc *sch)
{
	qdisc_skb_cb(skb)->pkt_len = skb->len;
	return qdisc_enqueue(skb, sch) & NET_XMIT_MASK;
}


static inline void bstats_update(struct gnet_stats_basic_packed *bstats,
				 const struct sk_buff *skb)
{
	bstats->bytes += qdisc_pkt_len(skb);
	bstats->packets += skb_is_gso(skb) ? skb_shinfo(skb)->gso_segs : 1;
}

static inline void qdisc_bstats_update(struct Qdisc *sch,
				       const struct sk_buff *skb)
{
	bstats_update(&sch->bstats, skb);
}

static inline int __qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch,
				       struct sk_buff_head *list)
{
	__skb_queue_tail(list, skb);
	sch->qstats.backlog += qdisc_pkt_len(skb);

	return NET_XMIT_SUCCESS;
}

static inline int qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch)
{
	return __qdisc_enqueue_tail(skb, sch, &sch->q);
}

static inline struct sk_buff *__qdisc_dequeue_head(struct Qdisc *sch,
						   struct sk_buff_head *list)
{
	struct sk_buff *skb = __skb_dequeue(list);

	if (likely(skb != NULL)) {
		sch->qstats.backlog -= qdisc_pkt_len(skb);
		qdisc_bstats_update(sch, skb);
	}

	return skb;
}

static inline struct sk_buff *qdisc_dequeue_head(struct Qdisc *sch)
{
	return __qdisc_dequeue_head(sch, &sch->q);
}

static inline unsigned int __qdisc_queue_drop_head(struct Qdisc *sch,
					      struct sk_buff_head *list)
{
	struct sk_buff *skb = __skb_dequeue(list);

	if (likely(skb != NULL)) {
		unsigned int len = qdisc_pkt_len(skb);
		sch->qstats.backlog -= len;
		kfree_skb(skb);
		return len;
	}

	return 0;
}

static inline unsigned int qdisc_queue_drop_head(struct Qdisc *sch)
{
	return __qdisc_queue_drop_head(sch, &sch->q);
}

static inline struct sk_buff *__qdisc_dequeue_tail(struct Qdisc *sch,
						   struct sk_buff_head *list)
{
	struct sk_buff *skb = __skb_dequeue_tail(list);

	if (likely(skb != NULL))
		sch->qstats.backlog -= qdisc_pkt_len(skb);

	return skb;
}

static inline struct sk_buff *qdisc_dequeue_tail(struct Qdisc *sch)
{
	return __qdisc_dequeue_tail(sch, &sch->q);
}

static inline struct sk_buff *qdisc_peek_head(struct Qdisc *sch)
{
	return skb_peek(&sch->q);
}

/* generic pseudo peek method for non-work-conserving qdisc */
static inline struct sk_buff *qdisc_peek_dequeued(struct Qdisc *sch)
{
	/* we can reuse ->gso_skb because peek isn't called for root qdiscs */
	if (!sch->gso_skb) {
		sch->gso_skb = sch->dequeue(sch);
		if (sch->gso_skb)
			/* it's still part of the queue */
			sch->q.qlen++;
	}

	return sch->gso_skb;
}

/* use instead of qdisc->dequeue() for all qdiscs queried with ->peek() */
static inline struct sk_buff *qdisc_dequeue_peeked(struct Qdisc *sch)
{
	struct sk_buff *skb = sch->gso_skb;

	if (skb) {
		sch->gso_skb = NULL;
		sch->q.qlen--;
	} else {
		skb = sch->dequeue(sch);
	}

	return skb;
}

static inline void __qdisc_reset_queue(struct Qdisc *sch,
				       struct sk_buff_head *list)
{
	/*
	 * We do not know the backlog in bytes of this list, it
	 * is up to the caller to correct it
	 */
	__skb_queue_purge(list);
}

static inline void qdisc_reset_queue(struct Qdisc *sch)
{
	__qdisc_reset_queue(sch, &sch->q);
	sch->qstats.backlog = 0;
}

static inline unsigned int __qdisc_queue_drop(struct Qdisc *sch,
					      struct sk_buff_head *list)
{
	struct sk_buff *skb = __qdisc_dequeue_tail(sch, list);

	if (likely(skb != NULL)) {
		unsigned int len = qdisc_pkt_len(skb);
		kfree_skb(skb);
		return len;
	}

	return 0;
}

static inline unsigned int qdisc_queue_drop(struct Qdisc *sch)
{
	return __qdisc_queue_drop(sch, &sch->q);
}

static inline int qdisc_drop(struct sk_buff *skb, struct Qdisc *sch)
{
	kfree_skb(skb);
	sch->qstats.drops++;

	return NET_XMIT_DROP;
}

static inline int qdisc_reshape_fail(struct sk_buff *skb, struct Qdisc *sch)
{
	sch->qstats.drops++;

#ifdef CONFIG_NET_CLS_ACT
	if (sch->reshape_fail == NULL || sch->reshape_fail(skb, sch))
		goto drop;

	return NET_XMIT_SUCCESS;

drop:
#endif
	kfree_skb(skb);
	return NET_XMIT_DROP;
}

/* Length to Time (L2T) lookup in a qdisc_rate_table, to determine how
   long it will take to send a packet given its size.
 */
static inline u32 qdisc_l2t(struct qdisc_rate_table* rtab, unsigned int pktlen)
{
	int slot = pktlen + rtab->rate.cell_align + rtab->rate.overhead;
	if (slot < 0)
		slot = 0;
	slot >>= rtab->rate.cell_log;
	if (slot > 255)
		return rtab->data[255]*(slot >> 8) + rtab->data[slot & 0xFF];
	return rtab->data[slot];
}

#ifdef CONFIG_NET_CLS_ACT
static inline struct sk_buff *skb_act_clone(struct sk_buff *skb, gfp_t gfp_mask,
					    int action)
{
	struct sk_buff *n;

	n = skb_clone(skb, gfp_mask);

	if (n) {
		n->tc_verd = SET_TC_VERD(n->tc_verd, 0);
		n->tc_verd = CLR_TC_OK2MUNGE(n->tc_verd);
		n->tc_verd = CLR_TC_MUNGED(n->tc_verd);
	}
	return n;
}
#endif

#endif