1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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 * $FreeBSD: stable/12/sys/netpfil/ipfw/ip_dn_private.h 371151 2021-12-06 14:19:21Z markj $
33 */
34
35 #ifndef _IP_DN_PRIVATE_H
36 #define _IP_DN_PRIVATE_H
37
38 /* debugging support
39 * use ND() to remove debugging, D() to print a line,
40 * DX(level, ...) to print above a certain level
41 * If you redefine D() you are expected to redefine all.
42 */
43 #ifndef D
44 #define ND(fmt, ...) do {} while (0)
45 #define D1(fmt, ...) do {} while (0)
46 #define D(fmt, ...) printf("%-10s " fmt "\n", \
47 __FUNCTION__, ## __VA_ARGS__)
48 #define DX(lev, fmt, ...) do { \
49 if (V_dn_cfg.debug > lev) D(fmt, ## __VA_ARGS__); } while (0)
50 #endif
51
52 MALLOC_DECLARE(M_DUMMYNET);
53
54 #ifndef __linux__
55 #define div64(a, b) ((int64_t)(a) / (int64_t)(b))
56 #endif
57
58 #define DN_LOCK_INIT() do { \
59 mtx_init(&V_dn_cfg.uh_mtx, "dn_uh", NULL, MTX_DEF); \
60 mtx_init(&V_dn_cfg.bh_mtx, "dn_bh", NULL, MTX_DEF); \
61 } while (0)
62 #define DN_LOCK_DESTROY() do { \
63 mtx_destroy(&V_dn_cfg.uh_mtx); \
64 mtx_destroy(&V_dn_cfg.bh_mtx); \
65 } while (0)
66 #if 0 /* not used yet */
67 #define DN_UH_RLOCK() mtx_lock(&V_dn_cfg.uh_mtx)
68 #define DN_UH_RUNLOCK() mtx_unlock(&V_dn_cfg.uh_mtx)
69 #define DN_UH_WLOCK() mtx_lock(&V_dn_cfg.uh_mtx)
70 #define DN_UH_WUNLOCK() mtx_unlock(&V_dn_cfg.uh_mtx)
71 #define DN_UH_LOCK_ASSERT() mtx_assert(&V_dn_cfg.uh_mtx, MA_OWNED)
72 #endif
73
74 #define DN_BH_RLOCK() mtx_lock(&V_dn_cfg.uh_mtx)
75 #define DN_BH_RUNLOCK() mtx_unlock(&V_dn_cfg.uh_mtx)
76 #define DN_BH_WLOCK() mtx_lock(&V_dn_cfg.uh_mtx)
77 #define DN_BH_WUNLOCK() mtx_unlock(&V_dn_cfg.uh_mtx)
78 #define DN_BH_LOCK_ASSERT() mtx_assert(&V_dn_cfg.uh_mtx, MA_OWNED)
79
80 SLIST_HEAD(dn_fsk_head, dn_fsk);
81
82 struct mq { /* a basic queue of packets*/
83 struct mbuf *head, *tail;
84 int count;
85 };
86
87 static inline void
set_oid(struct dn_id * o,int type,int len)88 set_oid(struct dn_id *o, int type, int len)
89 {
90 o->type = type;
91 o->len = len;
92 o->subtype = 0;
93 }
94
95 /*
96 * configuration and data for a dummynet instance
97 *
98 * When a configuration is modified from userland, 'id' is incremented
99 * so we can use the value to check for stale pointers.
100 */
101 struct dn_parms {
102 uint32_t id; /* configuration version */
103
104 /* defaults (sysctl-accessible) */
105 int red_lookup_depth;
106 int red_avg_pkt_size;
107 int red_max_pkt_size;
108 int hash_size;
109 int max_hash_size;
110 long byte_limit; /* max queue sizes */
111 long slot_limit;
112
113 int io_fast;
114 int debug;
115
116 /* timekeeping */
117 struct timeval prev_t; /* last time dummynet_tick ran */
118 struct dn_heap evheap; /* scheduled events */
119
120 long tick_last; /* Last tick duration (usec). */
121 long tick_delta; /* Last vs standard tick diff (usec). */
122 long tick_delta_sum; /* Accumulated tick difference (usec).*/
123 long tick_adjustment; /* Tick adjustments done. */
124 long tick_lost; /* Lost(coalesced) ticks number. */
125 /* Adjusted vs non-adjusted curr_time difference (ticks). */
126 long tick_diff;
127
128 /* counters of objects -- used for reporting space */
129 int schk_count;
130 int si_count;
131 int fsk_count;
132 int queue_count;
133
134 /* packet counters */
135 unsigned long io_pkt;
136 unsigned long io_pkt_fast;
137 unsigned long io_pkt_drop;
138
139 /* ticks and other stuff */
140 uint64_t curr_time;
141 /* flowsets and schedulers are in hash tables, with 'hash_size'
142 * buckets. fshash is looked up at every packet arrival
143 * so better be generous if we expect many entries.
144 */
145 struct dn_ht *fshash;
146 struct dn_ht *schedhash;
147 /* list of flowsets without a scheduler -- use sch_chain */
148 struct dn_fsk_head fsu; /* list of unlinked flowsets */
149
150 /* Store the fs/sch to scan when draining. The value is the
151 * bucket number of the hash table. Expire can be disabled
152 * with net.inet.ip.dummynet.expire=0, or it happens every
153 * expire ticks.
154 **/
155 int drain_fs;
156 int drain_sch;
157 uint32_t expire;
158 uint32_t expire_cycle; /* tick count */
159
160 int init_done;
161
162 #ifdef _KERNEL
163 /*
164 * This file is normally used in the kernel, unless we do
165 * some userland tests, in which case we do not need a mtx.
166 * uh_mtx arbitrates between system calls and also
167 * protects fshash, schedhash and fsunlinked.
168 * These structures are readonly for the lower half.
169 * bh_mtx protects all other structures which may be
170 * modified upon packet arrivals
171 */
172 #if defined( __linux__ ) || defined( _WIN32 )
173 spinlock_t uh_mtx;
174 spinlock_t bh_mtx;
175 #else
176 struct mtx uh_mtx;
177 struct mtx bh_mtx;
178 #endif
179
180 #endif /* _KERNEL */
181 };
182
183 /*
184 * Delay line, contains all packets on output from a link.
185 * Every scheduler instance has one.
186 */
187 struct delay_line {
188 struct dn_id oid;
189 struct dn_sch_inst *si;
190 struct mq mq;
191 };
192
193 /*
194 * The kernel side of a flowset. It is linked in a hash table
195 * of flowsets, and in a list of children of their parent scheduler.
196 * qht is either the queue or (if HAVE_MASK) a hash table queues.
197 * Note that the mask to use is the (flow_mask|sched_mask), which
198 * changes as we attach/detach schedulers. So we store it here.
199 *
200 * XXX If we want to add scheduler-specific parameters, we need to
201 * put them in external storage because the scheduler may not be
202 * available when the fsk is created.
203 */
204 struct dn_fsk { /* kernel side of a flowset */
205 struct dn_fs fs;
206 SLIST_ENTRY(dn_fsk) fsk_next; /* hash chain for fshash */
207
208 struct ipfw_flow_id fsk_mask;
209
210 /* qht is a hash table of queues, or just a single queue
211 * a bit in fs.flags tells us which one
212 */
213 struct dn_ht *qht;
214 struct dn_schk *sched; /* Sched we are linked to */
215 SLIST_ENTRY(dn_fsk) sch_chain; /* list of fsk attached to sched */
216
217 /* bucket index used by drain routine to drain queues for this
218 * flowset
219 */
220 int drain_bucket;
221 /* Parameter realted to RED / GRED */
222 /* original values are in dn_fs*/
223 int w_q ; /* queue weight (scaled) */
224 int max_th ; /* maximum threshold for queue (scaled) */
225 int min_th ; /* minimum threshold for queue (scaled) */
226 int max_p ; /* maximum value for p_b (scaled) */
227
228 u_int c_1 ; /* max_p/(max_th-min_th) (scaled) */
229 u_int c_2 ; /* max_p*min_th/(max_th-min_th) (scaled) */
230 u_int c_3 ; /* for GRED, (1-max_p)/max_th (scaled) */
231 u_int c_4 ; /* for GRED, 1 - 2*max_p (scaled) */
232 u_int * w_q_lookup ; /* lookup table for computing (1-w_q)^t */
233 u_int lookup_depth ; /* depth of lookup table */
234 int lookup_step ; /* granularity inside the lookup table */
235 int lookup_weight ; /* equal to (1-w_q)^t / (1-w_q)^(t+1) */
236 int avg_pkt_size ; /* medium packet size */
237 int max_pkt_size ; /* max packet size */
238 #ifdef NEW_AQM
239 struct dn_aqm *aqmfp; /* Pointer to AQM functions */
240 void *aqmcfg; /* configuration parameters for AQM */
241 #endif
242 };
243
244 /*
245 * A queue is created as a child of a flowset unless it belongs to
246 * a !MULTIQUEUE scheduler. It is normally in a hash table in the
247 * flowset. fs always points to the parent flowset.
248 * si normally points to the sch_inst, unless the flowset has been
249 * detached from the scheduler -- in this case si == NULL and we
250 * should not enqueue.
251 */
252 struct dn_queue {
253 struct dn_flow ni; /* oid, flow_id, stats */
254 struct mq mq; /* packets queue */
255 struct dn_sch_inst *_si; /* owner scheduler instance */
256 SLIST_ENTRY(dn_queue) q_next; /* hash chain list for qht */
257 struct dn_fsk *fs; /* parent flowset. */
258
259 /* RED parameters */
260 int avg; /* average queue length est. (scaled) */
261 int count; /* arrivals since last RED drop */
262 int random; /* random value (scaled) */
263 uint64_t q_time; /* start of queue idle time */
264 #ifdef NEW_AQM
265 void *aqm_status; /* per-queue status variables*/
266 #endif
267
268 };
269
270 /*
271 * The kernel side of a scheduler. Contains the userland config,
272 * a link, pointer to extra config arguments from command line,
273 * kernel flags, and a pointer to the scheduler methods.
274 * It is stored in a hash table, and holds a list of all
275 * flowsets and scheduler instances.
276 * XXX sch must be at the beginning, see schk_hash().
277 */
278 struct dn_schk {
279 struct dn_sch sch;
280 struct dn_alg *fp; /* Pointer to scheduler functions */
281 struct dn_link link; /* The link, embedded */
282 struct dn_profile *profile; /* delay profile, if any */
283 struct dn_id *cfg; /* extra config arguments */
284
285 SLIST_ENTRY(dn_schk) schk_next; /* hash chain for schedhash */
286
287 struct dn_fsk_head fsk_list; /* all fsk linked to me */
288 struct dn_fsk *fs; /* Flowset for !MULTIQUEUE */
289
290 /* bucket index used by the drain routine to drain the scheduler
291 * instance for this flowset.
292 */
293 int drain_bucket;
294
295 /* Hash table of all instances (through sch.sched_mask)
296 * or single instance if no mask. Always valid.
297 */
298 struct dn_ht *siht;
299 };
300
301
302 /*
303 * Scheduler instance.
304 * Contains variables and all queues relative to a this instance.
305 * This struct is created a runtime.
306 */
307 struct dn_sch_inst {
308 struct dn_flow ni; /* oid, flowid and stats */
309 SLIST_ENTRY(dn_sch_inst) si_next; /* hash chain for siht */
310 struct delay_line dline;
311 struct dn_schk *sched; /* the template */
312 int kflags; /* DN_ACTIVE */
313
314 int64_t credit; /* bits I can transmit (more or less). */
315 uint64_t sched_time; /* time link was scheduled in ready_heap */
316 uint64_t idle_time; /* start of scheduler instance idle time */
317
318 /* q_count is the number of queues that this instance is using.
319 * The counter is incremented or decremented when
320 * a reference from the queue is created or deleted.
321 * It is used to make sure that a scheduler instance can be safely
322 * deleted by the drain routine. See notes below.
323 */
324 int q_count;
325
326 };
327
328 /*
329 * NOTE about object drain.
330 * The system will automatically (XXX check when) drain queues and
331 * scheduler instances when they are idle.
332 * A queue is idle when it has no packets; an instance is idle when
333 * it is not in the evheap heap, and the corresponding delay line is empty.
334 * A queue can be safely deleted when it is idle because of the scheduler
335 * function xxx_free_queue() will remove any references to it.
336 * An instance can be only deleted when no queues reference it. To be sure
337 * of that, a counter (q_count) stores the number of queues that are pointing
338 * to the instance.
339 *
340 * XXX
341 * Order of scan:
342 * - take all flowset in a bucket for the flowset hash table
343 * - take all queues in a bucket for the flowset
344 * - increment the queue bucket
345 * - scan next flowset bucket
346 * Nothing is done if a bucket contains no entries.
347 *
348 * The same schema is used for sceduler instances
349 */
350
351
352 /* kernel-side flags. Linux has DN_DELETE in fcntl.h
353 */
354 enum {
355 /* 1 and 2 are reserved for the SCAN flags */
356 DN_DESTROY = 0x0004, /* destroy */
357 DN_DELETE_FS = 0x0008, /* destroy flowset */
358 DN_DETACH = 0x0010,
359 DN_ACTIVE = 0x0020, /* object is in evheap */
360 DN_F_DLINE = 0x0040, /* object is a delay line */
361 DN_DEL_SAFE = 0x0080, /* delete a queue only if no longer needed
362 * by scheduler */
363 DN_QHT_IS_Q = 0x0100, /* in flowset, qht is a single queue */
364 };
365
366 /*
367 * Packets processed by dummynet have an mbuf tag associated with
368 * them that carries their dummynet state.
369 * Outside dummynet, only the 'rule' field is relevant, and it must
370 * be at the beginning of the structure.
371 */
372 struct dn_pkt_tag {
373 struct ipfw_rule_ref rule; /* matching rule */
374
375 /* second part, dummynet specific */
376 int dn_dir; /* action when packet comes out.*/
377 /* see ip_fw_private.h */
378 uint64_t output_time; /* when the pkt is due for delivery*/
379 struct ifnet *ifp; /* interface, for ip_output */
380 struct _ip6dn_args ip6opt; /* XXX ipv6 options */
381 uint16_t iphdr_off; /* IP header offset for mtodo() */
382 };
383
384 VNET_DECLARE(struct dn_parms, dn_cfg);
385 #define V_dn_cfg VNET(dn_cfg)
386
387 int dummynet_io(struct mbuf **, int , struct ip_fw_args *);
388 void dummynet_task(void *context, int pending);
389 void dn_reschedule(void);
390 struct dn_pkt_tag * dn_tag_get(struct mbuf *m);
391
392 struct dn_queue *ipdn_q_find(struct dn_fsk *, struct dn_sch_inst *,
393 struct ipfw_flow_id *);
394 struct dn_sch_inst *ipdn_si_find(struct dn_schk *, struct ipfw_flow_id *);
395
396 /*
397 * copy_range is a template for requests for ranges of pipes/queues/scheds.
398 * The number of ranges is variable and can be derived by o.len.
399 * As a default, we use a small number of entries so that the struct
400 * fits easily on the stack and is sufficient for most common requests.
401 */
402 #define DEFAULT_RANGES 5
403 struct copy_range {
404 struct dn_id o;
405 uint32_t r[ 2 * DEFAULT_RANGES ];
406 };
407
408 struct copy_args {
409 char **start;
410 char *end;
411 int flags;
412 int type;
413 struct copy_range *extra; /* extra filtering */
414 };
415
416 struct sockopt;
417 int ip_dummynet_compat(struct sockopt *sopt);
418 int dummynet_get(struct sockopt *sopt, void **compat);
419 int dn_c_copy_q (void *_ni, void *arg);
420 int dn_c_copy_pipe(struct dn_schk *s, struct copy_args *a, int nq);
421 int dn_c_copy_fs(struct dn_fsk *f, struct copy_args *a, int nq);
422 int dn_compat_copy_queue(struct copy_args *a, void *_o);
423 int dn_compat_copy_pipe(struct copy_args *a, void *_o);
424 int copy_data_helper_compat(void *_o, void *_arg);
425 int dn_compat_calc_size(void);
426 int do_config(void *p, size_t l);
427
428 /* function to drain idle object */
429 void dn_drain_scheduler(void);
430 void dn_drain_queue(void);
431
432 #ifdef NEW_AQM
433 int ecn_mark(struct mbuf* m);
434
435 /* moved from ip_dn_io.c to here to be available for AQMs modules*/
436 static inline void
mq_append(struct mq * q,struct mbuf * m)437 mq_append(struct mq *q, struct mbuf *m)
438 {
439 #ifdef USERSPACE
440 // buffers from netmap need to be copied
441 // XXX note that the routine is not expected to fail
442 ND("append %p to %p", m, q);
443 if (m->m_flags & M_STACK) {
444 struct mbuf *m_new;
445 void *p;
446 int l, ofs;
447
448 ofs = m->m_data - m->__m_extbuf;
449 // XXX allocate
450 MGETHDR(m_new, M_NOWAIT, MT_DATA);
451 ND("*** WARNING, volatile buf %p ext %p %d dofs %d m_new %p",
452 m, m->__m_extbuf, m->__m_extlen, ofs, m_new);
453 p = m_new->__m_extbuf; /* new pointer */
454 l = m_new->__m_extlen; /* new len */
455 if (l <= m->__m_extlen) {
456 panic("extlen too large");
457 }
458
459 *m_new = *m; // copy
460 m_new->m_flags &= ~M_STACK;
461 m_new->__m_extbuf = p; // point to new buffer
462 _pkt_copy(m->__m_extbuf, p, m->__m_extlen);
463 m_new->m_data = p + ofs;
464 m = m_new;
465 }
466 #endif /* USERSPACE */
467 if (q->head == NULL)
468 q->head = m;
469 else
470 q->tail->m_nextpkt = m;
471 q->count++;
472 q->tail = m;
473 m->m_nextpkt = NULL;
474 }
475 #endif /* NEW_AQM */
476
477 #endif /* _IP_DN_PRIVATE_H */
478