1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2010 Luigi Rizzo, Riccardo Panicucci, Universita` di Pisa
5 * All rights reserved
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29/*
30 * internal dummynet APIs.
31 */
32
33#ifndef _IP_DN_PRIVATE_H
34#define _IP_DN_PRIVATE_H
35
36/* debugging support
37 * use ND() to remove debugging, D() to print a line,
38 * DX(level, ...) to print above a certain level
39 * If you redefine D() you are expected to redefine all.
40 */
41#ifndef D
42#define ND(fmt, ...) do {} while (0)
43#define D1(fmt, ...) do {} while (0)
44#define D(fmt, ...) printf("%-10s " fmt "\n",      \
45        __FUNCTION__, ## __VA_ARGS__)
46#define DX(lev, fmt, ...) do {              \
47        if (V_dn_cfg.debug > lev) D(fmt, ## __VA_ARGS__); } while (0)
48#endif
49
50MALLOC_DECLARE(M_DUMMYNET);
51
52#ifndef __linux__
53#define div64(a, b)  ((int64_t)(a) / (int64_t)(b))
54#endif
55
56#define DN_LOCK_INIT() do {				\
57	mtx_init(&V_dn_cfg.uh_mtx, "dn_uh", NULL, MTX_DEF);	\
58	mtx_init(&V_dn_cfg.bh_mtx, "dn_bh", NULL, MTX_DEF);	\
59	} while (0)
60#define DN_LOCK_DESTROY() do {				\
61	mtx_destroy(&V_dn_cfg.uh_mtx);			\
62	mtx_destroy(&V_dn_cfg.bh_mtx);			\
63	} while (0)
64#if 0 /* not used yet */
65#define DN_UH_RLOCK()		mtx_lock(&V_dn_cfg.uh_mtx)
66#define DN_UH_RUNLOCK()		mtx_unlock(&V_dn_cfg.uh_mtx)
67#define DN_UH_WLOCK()		mtx_lock(&V_dn_cfg.uh_mtx)
68#define DN_UH_WUNLOCK()		mtx_unlock(&V_dn_cfg.uh_mtx)
69#define DN_UH_LOCK_ASSERT()	mtx_assert(&V_dn_cfg.uh_mtx, MA_OWNED)
70#endif
71
72#define DN_BH_RLOCK()		mtx_lock(&V_dn_cfg.uh_mtx)
73#define DN_BH_RUNLOCK()		mtx_unlock(&V_dn_cfg.uh_mtx)
74#define DN_BH_WLOCK()		mtx_lock(&V_dn_cfg.uh_mtx)
75#define DN_BH_WUNLOCK()		mtx_unlock(&V_dn_cfg.uh_mtx)
76#define DN_BH_LOCK_ASSERT()	mtx_assert(&V_dn_cfg.uh_mtx, MA_OWNED)
77
78SLIST_HEAD(dn_fsk_head, dn_fsk);
79
80struct mq {	/* a basic queue of packets*/
81        struct mbuf *head, *tail;
82	int count;
83};
84
85static inline void
86set_oid(struct dn_id *o, int type, int len)
87{
88        o->type = type;
89        o->len = len;
90        o->subtype = 0;
91}
92
93/*
94 * configuration and data for a dummynet instance
95 *
96 * When a configuration is modified from userland, 'id' is incremented
97 * so we can use the value to check for stale pointers.
98 */
99struct dn_parms {
100	uint32_t	id;		/* configuration version */
101
102	/* defaults (sysctl-accessible) */
103	int	red_lookup_depth;
104	int	red_avg_pkt_size;
105	int	red_max_pkt_size;
106	int	hash_size;
107	int	max_hash_size;
108	long	byte_limit;		/* max queue sizes */
109	long	slot_limit;
110
111	int	io_fast;
112	int	debug;
113
114	/* timekeeping */
115	struct timeval prev_t;		/* last time dummynet_tick ran */
116	struct dn_heap	evheap;		/* scheduled events */
117
118	long	tick_last;		/* Last tick duration (usec). */
119	long	tick_delta;		/* Last vs standard tick diff (usec). */
120	long	tick_delta_sum;	/* Accumulated tick difference (usec).*/
121	long	tick_adjustment;	/* Tick adjustments done. */
122	long	tick_lost;		/* Lost(coalesced) ticks number. */
123	/* Adjusted vs non-adjusted curr_time difference (ticks). */
124	long	tick_diff;
125
126	/* counters of objects -- used for reporting space */
127	int	schk_count;
128	int	si_count;
129	int	fsk_count;
130	int	queue_count;
131
132	/* packet counters */
133	unsigned long	io_pkt;
134	unsigned long	io_pkt_fast;
135	unsigned long	io_pkt_drop;
136
137	/* ticks and other stuff */
138	uint64_t	curr_time;
139	/* flowsets and schedulers are in hash tables, with 'hash_size'
140	 * buckets. fshash is looked up at every packet arrival
141	 * so better be generous if we expect many entries.
142	 */
143	struct dn_ht	*fshash;
144	struct dn_ht	*schedhash;
145	/* list of flowsets without a scheduler -- use sch_chain */
146	struct dn_fsk_head	fsu;	/* list of unlinked flowsets */
147
148	/* Store the fs/sch to scan when draining. The value is the
149	 * bucket number of the hash table. Expire can be disabled
150	 * with net.inet.ip.dummynet.expire=0, or it happens every
151	 * expire ticks.
152	 **/
153	int drain_fs;
154	int drain_sch;
155	uint32_t expire;
156	uint32_t expire_cycle;	/* tick count */
157
158	int init_done;
159
160#ifdef _KERNEL
161	/*
162	 * This file is normally used in the kernel, unless we do
163	 * some userland tests, in which case we do not need a mtx.
164	 * uh_mtx arbitrates between system calls and also
165	 * protects fshash, schedhash and fsunlinked.
166	 * These structures are readonly for the lower half.
167	 * bh_mtx protects all other structures which may be
168	 * modified upon packet arrivals
169	 */
170#if defined( __linux__ ) || defined( _WIN32 )
171	spinlock_t uh_mtx;
172	spinlock_t bh_mtx;
173#else
174	struct mtx uh_mtx;
175	struct mtx bh_mtx;
176#endif
177
178#endif /* _KERNEL */
179};
180
181/*
182 * Delay line, contains all packets on output from a link.
183 * Every scheduler instance has one.
184 */
185struct delay_line {
186	struct dn_id oid;
187	struct dn_sch_inst *si;
188	struct mq mq;
189};
190
191/*
192 * The kernel side of a flowset. It is linked in a hash table
193 * of flowsets, and in a list of children of their parent scheduler.
194 * qht is either the queue or (if HAVE_MASK) a hash table queues.
195 * Note that the mask to use is the (flow_mask|sched_mask), which
196 * changes as we attach/detach schedulers. So we store it here.
197 *
198 * XXX If we want to add scheduler-specific parameters, we need to
199 * put them in external storage because the scheduler may not be
200 * available when the fsk is created.
201 */
202struct dn_fsk { /* kernel side of a flowset */
203	struct dn_fs fs;
204	SLIST_ENTRY(dn_fsk) fsk_next;	/* hash chain for fshash */
205
206	struct ipfw_flow_id fsk_mask;
207
208	/* qht is a hash table of queues, or just a single queue
209	 * a bit in fs.flags tells us which one
210	 */
211	struct dn_ht	*qht;
212	struct dn_schk *sched;		/* Sched we are linked to */
213	SLIST_ENTRY(dn_fsk) sch_chain;	/* list of fsk attached to sched */
214
215	/* bucket index used by drain routine to drain queues for this
216	 * flowset
217	 */
218	int drain_bucket;
219	/* Parameter realted to RED / GRED */
220	/* original values are in dn_fs*/
221	int w_q ;		/* queue weight (scaled) */
222	int max_th ;		/* maximum threshold for queue (scaled) */
223	int min_th ;		/* minimum threshold for queue (scaled) */
224	int max_p ;		/* maximum value for p_b (scaled) */
225
226	u_int c_1 ;		/* max_p/(max_th-min_th) (scaled) */
227	u_int c_2 ;		/* max_p*min_th/(max_th-min_th) (scaled) */
228	u_int c_3 ;		/* for GRED, (1-max_p)/max_th (scaled) */
229	u_int c_4 ;		/* for GRED, 1 - 2*max_p (scaled) */
230	u_int * w_q_lookup ;	/* lookup table for computing (1-w_q)^t */
231	u_int lookup_depth ;	/* depth of lookup table */
232	int lookup_step ;	/* granularity inside the lookup table */
233	int lookup_weight ;	/* equal to (1-w_q)^t / (1-w_q)^(t+1) */
234	int avg_pkt_size ;	/* medium packet size */
235	int max_pkt_size ;	/* max packet size */
236#ifdef NEW_AQM
237	struct dn_aqm *aqmfp;	/* Pointer to AQM functions */
238	void *aqmcfg;	/* configuration parameters for AQM */
239#endif
240};
241
242/*
243 * A queue is created as a child of a flowset unless it belongs to
244 * a !MULTIQUEUE scheduler. It is normally in a hash table in the
245 * flowset. fs always points to the parent flowset.
246 * si normally points to the sch_inst, unless the flowset has been
247 * detached from the scheduler -- in this case si == NULL and we
248 * should not enqueue.
249 */
250struct dn_queue {
251	struct dn_flow ni;	/* oid, flow_id, stats */
252	struct mq mq;	/* packets queue */
253	struct dn_sch_inst *_si;	/* owner scheduler instance */
254	SLIST_ENTRY(dn_queue) q_next; /* hash chain list for qht */
255	struct dn_fsk *fs;		/* parent flowset. */
256
257	/* RED parameters */
258	int avg;		/* average queue length est. (scaled) */
259	int count;		/* arrivals since last RED drop */
260	int random;		/* random value (scaled) */
261	uint64_t q_time;	/* start of queue idle time */
262#ifdef NEW_AQM
263	void *aqm_status;	/* per-queue status variables*/
264#endif
265
266};
267
268/*
269 * The kernel side of a scheduler. Contains the userland config,
270 * a link, pointer to extra config arguments from command line,
271 * kernel flags, and a pointer to the scheduler methods.
272 * It is stored in a hash table, and holds a list of all
273 * flowsets and scheduler instances.
274 * XXX sch must be at the beginning, see schk_hash().
275 */
276struct dn_schk {
277	struct dn_sch sch;
278	struct dn_alg *fp;	/* Pointer to scheduler functions */
279	struct dn_link link;	/* The link, embedded */
280	struct dn_profile *profile; /* delay profile, if any */
281	struct dn_id *cfg;	/* extra config arguments */
282
283	SLIST_ENTRY(dn_schk) schk_next;  /* hash chain for schedhash */
284
285	struct dn_fsk_head fsk_list;  /* all fsk linked to me */
286	struct dn_fsk *fs;	/* Flowset for !MULTIQUEUE */
287
288	/* bucket index used by the drain routine to drain the scheduler
289	 * instance for this flowset.
290	 */
291	int drain_bucket;
292
293	/* Hash table of all instances (through sch.sched_mask)
294	 * or single instance if no mask. Always valid.
295	 */
296	struct dn_ht	*siht;
297};
298
299/*
300 * Scheduler instance.
301 * Contains variables and all queues relative to a this instance.
302 * This struct is created a runtime.
303 */
304struct dn_sch_inst {
305	struct dn_flow	ni;	/* oid, flowid and stats */
306	SLIST_ENTRY(dn_sch_inst) si_next; /* hash chain for siht */
307	struct delay_line dline;
308	struct dn_schk *sched;	/* the template */
309	int		kflags;	/* DN_ACTIVE */
310
311	int64_t	credit;		/* bits I can transmit (more or less). */
312	uint64_t sched_time;	/* time link was scheduled in ready_heap */
313	uint64_t idle_time;	/* start of scheduler instance idle time */
314
315	/* q_count is the number of queues that this instance is using.
316	 * The counter is incremented or decremented when
317	 * a reference from the queue is created or deleted.
318	 * It is used to make sure that a scheduler instance can be safely
319	 * deleted by the drain routine. See notes below.
320	 */
321	int q_count;
322
323};
324
325/*
326 * NOTE about object drain.
327 * The system will automatically (XXX check when) drain queues and
328 * scheduler instances when they are idle.
329 * A queue is idle when it has no packets; an instance is idle when
330 * it is not in the evheap heap, and the corresponding delay line is empty.
331 * A queue can be safely deleted when it is idle because of the scheduler
332 * function xxx_free_queue() will remove any references to it.
333 * An instance can be only deleted when no queues reference it. To be sure
334 * of that, a counter (q_count) stores the number of queues that are pointing
335 * to the instance.
336 *
337 * XXX
338 * Order of scan:
339 * - take all flowset in a bucket for the flowset hash table
340 * - take all queues in a bucket for the flowset
341 * - increment the queue bucket
342 * - scan next flowset bucket
343 * Nothing is done if a bucket contains no entries.
344 *
345 * The same schema is used for sceduler instances
346 */
347
348/* kernel-side flags. Linux has DN_DELETE in fcntl.h
349 */
350enum {
351	/* 1 and 2 are reserved for the SCAN flags */
352	DN_DESTROY	= 0x0004, /* destroy */
353	DN_DELETE_FS	= 0x0008, /* destroy flowset */
354	DN_DETACH	= 0x0010,
355	DN_ACTIVE	= 0x0020, /* object is in evheap */
356	DN_F_DLINE	= 0x0040, /* object is a delay line */
357	DN_DEL_SAFE	= 0x0080, /* delete a queue only if no longer needed
358				   * by scheduler */
359	DN_QHT_IS_Q	= 0x0100, /* in flowset, qht is a single queue */
360};
361
362/*
363 * Packets processed by dummynet have an mbuf tag associated with
364 * them that carries their dummynet state.
365 * Outside dummynet, only the 'rule' field is relevant, and it must
366 * be at the beginning of the structure.
367 */
368struct dn_pkt_tag {
369	struct ipfw_rule_ref rule;	/* matching rule	*/
370
371	/* second part, dummynet specific */
372	int dn_dir;		/* action when packet comes out.*/
373				/* see ip_fw_private.h		*/
374	uint64_t output_time;	/* when the pkt is due for delivery*/
375	uint16_t if_index;
376	uint16_t if_idxgen;
377	uint16_t iphdr_off;	/* IP header offset for mtodo()	*/
378};
379
380/*
381 * Possible values for dn_dir. XXXGL: this needs to be reviewed
382 * and converted to same values ip_fw_args.flags use.
383 */
384enum {
385	DIR_OUT =	0,
386	DIR_IN =	1,
387	DIR_FWD =	2,
388	DIR_DROP =	3,
389	PROTO_LAYER2 =	0x4, /* set for layer 2 */
390	PROTO_IPV4 =	0x08,
391	PROTO_IPV6 =	0x10,
392	PROTO_IFB =	0x0c, /* layer2 + ifbridge */
393};
394
395/*
396 * States for the Packet Loss Rate Gilbert-Elliott
397 * channel model
398 */
399enum {
400	PLR_STATE_G = 0,
401	PLR_STATE_B,
402};
403
404//extern struct dn_parms V_dn_cfg;
405VNET_DECLARE(struct dn_parms, dn_cfg);
406#define V_dn_cfg	VNET(dn_cfg)
407
408int dummynet_io(struct mbuf **, struct ip_fw_args *);
409void dummynet_sched_lock(void);
410void dummynet_sched_unlock(void);
411void dummynet_task(void *context, int pending);
412void dn_reschedule(void);
413struct dn_pkt_tag * dn_tag_get(struct mbuf *m);
414
415struct dn_queue *ipdn_q_find(struct dn_fsk *, struct dn_sch_inst *,
416        struct ipfw_flow_id *);
417struct dn_sch_inst *ipdn_si_find(struct dn_schk *, struct ipfw_flow_id *);
418
419/*
420 * copy_range is a template for requests for ranges of pipes/queues/scheds.
421 * The number of ranges is variable and can be derived by o.len.
422 * As a default, we use a small number of entries so that the struct
423 * fits easily on the stack and is sufficient for most common requests.
424 */
425#define DEFAULT_RANGES	5
426struct copy_range {
427        struct dn_id o;
428        uint32_t	r[ 2 * DEFAULT_RANGES ];
429};
430
431struct copy_args {
432	char **start;
433	char *end;
434	int flags;
435	int type;
436	struct copy_range *extra;	/* extra filtering */
437};
438
439struct sockopt;
440int ip_dummynet_compat(struct sockopt *sopt);
441int dummynet_get(struct sockopt *sopt, void **compat);
442int dn_c_copy_q (void *_ni, void *arg);
443int dn_c_copy_pipe(struct dn_schk *s, struct copy_args *a, int nq);
444int dn_c_copy_fs(struct dn_fsk *f, struct copy_args *a, int nq);
445int dn_compat_copy_queue(struct copy_args *a, void *_o);
446int dn_compat_copy_pipe(struct copy_args *a, void *_o);
447int copy_data_helper_compat(void *_o, void *_arg);
448int dn_compat_calc_size(void);
449int do_config(void *p, size_t l);
450
451/* function to drain idle object */
452void dn_drain_scheduler(void);
453void dn_drain_queue(void);
454
455#ifdef NEW_AQM
456int ecn_mark(struct mbuf* m);
457
458/* moved from ip_dn_io.c to here to be available for AQMs modules*/
459static inline void
460mq_append(struct mq *q, struct mbuf *m)
461{
462#ifdef USERSPACE
463	// buffers from netmap need to be copied
464	// XXX note that the routine is not expected to fail
465	ND("append %p to %p", m, q);
466	if (m->m_flags & M_STACK) {
467		struct mbuf *m_new;
468		void *p;
469		int l, ofs;
470
471		ofs = m->m_data - m->__m_extbuf;
472		// XXX allocate
473		MGETHDR(m_new, M_NOWAIT, MT_DATA);
474		ND("*** WARNING, volatile buf %p ext %p %d dofs %d m_new %p",
475			m, m->__m_extbuf, m->__m_extlen, ofs, m_new);
476		p = m_new->__m_extbuf;	/* new pointer */
477		l = m_new->__m_extlen;	/* new len */
478		if (l <= m->__m_extlen) {
479			panic("extlen too large");
480		}
481
482		*m_new = *m;	// copy
483		m_new->m_flags &= ~M_STACK;
484		m_new->__m_extbuf = p; // point to new buffer
485		_pkt_copy(m->__m_extbuf, p, m->__m_extlen);
486		m_new->m_data = p + ofs;
487		m = m_new;
488	}
489#endif /* USERSPACE */
490	if (q->head == NULL)
491		q->head = m;
492	else
493		q->tail->m_nextpkt = m;
494	q->count++;
495	q->tail = m;
496	m->m_nextpkt = NULL;
497}
498#endif /* NEW_AQM */
499
500#endif /* _IP_DN_PRIVATE_H */
501