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 * $FreeBSD$
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 (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(&dn_cfg.uh_mtx, "dn_uh", NULL, MTX_DEF); \
60 mtx_init(&dn_cfg.bh_mtx, "dn_bh", NULL, MTX_DEF); \
61 } while (0)
62 #define DN_LOCK_DESTROY() do { \
63 mtx_destroy(&dn_cfg.uh_mtx); \
64 mtx_destroy(&dn_cfg.bh_mtx); \
65 } while (0)
66 #if 0 /* not used yet */
67 #define DN_UH_RLOCK() mtx_lock(&dn_cfg.uh_mtx)
68 #define DN_UH_RUNLOCK() mtx_unlock(&dn_cfg.uh_mtx)
69 #define DN_UH_WLOCK() mtx_lock(&dn_cfg.uh_mtx)
70 #define DN_UH_WUNLOCK() mtx_unlock(&dn_cfg.uh_mtx)
71 #define DN_UH_LOCK_ASSERT() mtx_assert(&dn_cfg.uh_mtx, MA_OWNED)
72 #endif
73
74 #define DN_BH_RLOCK() mtx_lock(&dn_cfg.uh_mtx)
75 #define DN_BH_RUNLOCK() mtx_unlock(&dn_cfg.uh_mtx)
76 #define DN_BH_WLOCK() mtx_lock(&dn_cfg.uh_mtx)
77 #define DN_BH_WUNLOCK() mtx_unlock(&dn_cfg.uh_mtx)
78 #define DN_BH_LOCK_ASSERT() mtx_assert(&dn_cfg.uh_mtx, MA_OWNED)
79
80 SLIST_HEAD(dn_schk_head, dn_schk);
81 SLIST_HEAD(dn_sch_inst_head, dn_sch_inst);
82 SLIST_HEAD(dn_fsk_head, dn_fsk);
83 SLIST_HEAD(dn_queue_head, dn_queue);
84 SLIST_HEAD(dn_alg_head, dn_alg);
85
86 #ifdef NEW_AQM
87 SLIST_HEAD(dn_aqm_head, dn_aqm); /* for new AQMs */
88 #endif
89
90 struct mq { /* a basic queue of packets*/
91 struct mbuf *head, *tail;
92 int count;
93 };
94
95 static inline void
set_oid(struct dn_id * o,int type,int len)96 set_oid(struct dn_id *o, int type, int len)
97 {
98 o->type = type;
99 o->len = len;
100 o->subtype = 0;
101 }
102
103 /*
104 * configuration and global data for a dummynet instance
105 *
106 * When a configuration is modified from userland, 'id' is incremented
107 * so we can use the value to check for stale pointers.
108 */
109 struct dn_parms {
110 uint32_t id; /* configuration version */
111
112 /* defaults (sysctl-accessible) */
113 int red_lookup_depth;
114 int red_avg_pkt_size;
115 int red_max_pkt_size;
116 int hash_size;
117 int max_hash_size;
118 long byte_limit; /* max queue sizes */
119 long slot_limit;
120
121 int io_fast;
122 int debug;
123
124 /* timekeeping */
125 struct timeval prev_t; /* last time dummynet_tick ran */
126 struct dn_heap evheap; /* scheduled events */
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 /* ticks and other stuff */
135 uint64_t curr_time;
136 /* flowsets and schedulers are in hash tables, with 'hash_size'
137 * buckets. fshash is looked up at every packet arrival
138 * so better be generous if we expect many entries.
139 */
140 struct dn_ht *fshash;
141 struct dn_ht *schedhash;
142 /* list of flowsets without a scheduler -- use sch_chain */
143 struct dn_fsk_head fsu; /* list of unlinked flowsets */
144 struct dn_alg_head schedlist; /* list of algorithms */
145 #ifdef NEW_AQM
146 struct dn_aqm_head aqmlist; /* list of AQMs */
147 #endif
148
149 /* Store the fs/sch to scan when draining. The value is the
150 * bucket number of the hash table. Expire can be disabled
151 * with net.inet.ip.dummynet.expire=0, or it happens every
152 * expire ticks.
153 **/
154 int drain_fs;
155 int drain_sch;
156 uint32_t expire;
157 uint32_t expire_cycle; /* tick count */
158
159 int init_done;
160
161 /* if the upper half is busy doing something long,
162 * can set the busy flag and we will enqueue packets in
163 * a queue for later processing.
164 */
165 int busy;
166 struct mq pending;
167
168 #ifdef _KERNEL
169 /*
170 * This file is normally used in the kernel, unless we do
171 * some userland tests, in which case we do not need a mtx.
172 * uh_mtx arbitrates between system calls and also
173 * protects fshash, schedhash and fsunlinked.
174 * These structures are readonly for the lower half.
175 * bh_mtx protects all other structures which may be
176 * modified upon packet arrivals
177 */
178 #if defined( __linux__ ) || defined( _WIN32 )
179 spinlock_t uh_mtx;
180 spinlock_t bh_mtx;
181 #else
182 struct mtx uh_mtx;
183 struct mtx bh_mtx;
184 #endif
185
186 #endif /* _KERNEL */
187 };
188
189 /*
190 * Delay line, contains all packets on output from a link.
191 * Every scheduler instance has one.
192 */
193 struct delay_line {
194 struct dn_id oid;
195 struct dn_sch_inst *si;
196 struct mq mq;
197 };
198
199 /*
200 * The kernel side of a flowset. It is linked in a hash table
201 * of flowsets, and in a list of children of their parent scheduler.
202 * qht is either the queue or (if HAVE_MASK) a hash table queues.
203 * Note that the mask to use is the (flow_mask|sched_mask), which
204 * changes as we attach/detach schedulers. So we store it here.
205 *
206 * XXX If we want to add scheduler-specific parameters, we need to
207 * put them in external storage because the scheduler may not be
208 * available when the fsk is created.
209 */
210 struct dn_fsk { /* kernel side of a flowset */
211 struct dn_fs fs;
212 SLIST_ENTRY(dn_fsk) fsk_next; /* hash chain for fshash */
213
214 struct ipfw_flow_id fsk_mask;
215
216 /* qht is a hash table of queues, or just a single queue
217 * a bit in fs.flags tells us which one
218 */
219 struct dn_ht *qht;
220 struct dn_schk *sched; /* Sched we are linked to */
221 SLIST_ENTRY(dn_fsk) sch_chain; /* list of fsk attached to sched */
222
223 /* bucket index used by drain routine to drain queues for this
224 * flowset
225 */
226 int drain_bucket;
227 /* Parameter realted to RED / GRED */
228 /* original values are in dn_fs*/
229 int w_q ; /* queue weight (scaled) */
230 int max_th ; /* maximum threshold for queue (scaled) */
231 int min_th ; /* minimum threshold for queue (scaled) */
232 int max_p ; /* maximum value for p_b (scaled) */
233
234 u_int c_1 ; /* max_p/(max_th-min_th) (scaled) */
235 u_int c_2 ; /* max_p*min_th/(max_th-min_th) (scaled) */
236 u_int c_3 ; /* for GRED, (1-max_p)/max_th (scaled) */
237 u_int c_4 ; /* for GRED, 1 - 2*max_p (scaled) */
238 u_int * w_q_lookup ; /* lookup table for computing (1-w_q)^t */
239 u_int lookup_depth ; /* depth of lookup table */
240 int lookup_step ; /* granularity inside the lookup table */
241 int lookup_weight ; /* equal to (1-w_q)^t / (1-w_q)^(t+1) */
242 int avg_pkt_size ; /* medium packet size */
243 int max_pkt_size ; /* max packet size */
244 #ifdef NEW_AQM
245 struct dn_aqm *aqmfp; /* Pointer to AQM functions */
246 void *aqmcfg; /* configuration parameters for AQM */
247 #endif
248 };
249
250 /*
251 * A queue is created as a child of a flowset unless it belongs to
252 * a !MULTIQUEUE scheduler. It is normally in a hash table in the
253 * flowset. fs always points to the parent flowset.
254 * si normally points to the sch_inst, unless the flowset has been
255 * detached from the scheduler -- in this case si == NULL and we
256 * should not enqueue.
257 */
258 struct dn_queue {
259 struct dn_flow ni; /* oid, flow_id, stats */
260 struct mq mq; /* packets queue */
261 struct dn_sch_inst *_si; /* owner scheduler instance */
262 SLIST_ENTRY(dn_queue) q_next; /* hash chain list for qht */
263 struct dn_fsk *fs; /* parent flowset. */
264
265 /* RED parameters */
266 int avg; /* average queue length est. (scaled) */
267 int count; /* arrivals since last RED drop */
268 int random; /* random value (scaled) */
269 uint64_t q_time; /* start of queue idle time */
270 #ifdef NEW_AQM
271 void *aqm_status; /* per-queue status variables*/
272 #endif
273
274 };
275
276 /*
277 * The kernel side of a scheduler. Contains the userland config,
278 * a link, pointer to extra config arguments from command line,
279 * kernel flags, and a pointer to the scheduler methods.
280 * It is stored in a hash table, and holds a list of all
281 * flowsets and scheduler instances.
282 * XXX sch must be at the beginning, see schk_hash().
283 */
284 struct dn_schk {
285 struct dn_sch sch;
286 struct dn_alg *fp; /* Pointer to scheduler functions */
287 struct dn_link link; /* The link, embedded */
288 struct dn_profile *profile; /* delay profile, if any */
289 struct dn_id *cfg; /* extra config arguments */
290
291 SLIST_ENTRY(dn_schk) schk_next; /* hash chain for schedhash */
292
293 struct dn_fsk_head fsk_list; /* all fsk linked to me */
294 struct dn_fsk *fs; /* Flowset for !MULTIQUEUE */
295
296 /* bucket index used by the drain routine to drain the scheduler
297 * instance for this flowset.
298 */
299 int drain_bucket;
300
301 /* Hash table of all instances (through sch.sched_mask)
302 * or single instance if no mask. Always valid.
303 */
304 struct dn_ht *siht;
305 };
306
307
308 /*
309 * Scheduler instance.
310 * Contains variables and all queues relative to a this instance.
311 * This struct is created a runtime.
312 */
313 struct dn_sch_inst {
314 struct dn_flow ni; /* oid, flowid and stats */
315 SLIST_ENTRY(dn_sch_inst) si_next; /* hash chain for siht */
316 struct delay_line dline;
317 struct dn_schk *sched; /* the template */
318 int kflags; /* DN_ACTIVE */
319
320 int64_t credit; /* bits I can transmit (more or less). */
321 uint64_t sched_time; /* time link was scheduled in ready_heap */
322 uint64_t idle_time; /* start of scheduler instance idle time */
323
324 /* q_count is the number of queues that this instance is using.
325 * The counter is incremented or decremented when
326 * a reference from the queue is created or deleted.
327 * It is used to make sure that a scheduler instance can be safely
328 * deleted by the drain routine. See notes below.
329 */
330 int q_count;
331
332 };
333
334 /*
335 * NOTE about object drain.
336 * The system will automatically (XXX check when) drain queues and
337 * scheduler instances when they are idle.
338 * A queue is idle when it has no packets; an instance is idle when
339 * it is not in the evheap heap, and the corresponding delay line is empty.
340 * A queue can be safely deleted when it is idle because of the scheduler
341 * function xxx_free_queue() will remove any references to it.
342 * An instance can be only deleted when no queues reference it. To be sure
343 * of that, a counter (q_count) stores the number of queues that are pointing
344 * to the instance.
345 *
346 * XXX
347 * Order of scan:
348 * - take all flowset in a bucket for the flowset hash table
349 * - take all queues in a bucket for the flowset
350 * - increment the queue bucket
351 * - scan next flowset bucket
352 * Nothing is done if a bucket contains no entries.
353 *
354 * The same schema is used for sceduler instances
355 */
356
357
358 /* kernel-side flags. Linux has DN_DELETE in fcntl.h
359 */
360 enum {
361 /* 1 and 2 are reserved for the SCAN flags */
362 DN_DESTROY = 0x0004, /* destroy */
363 DN_DELETE_FS = 0x0008, /* destroy flowset */
364 DN_DETACH = 0x0010,
365 DN_ACTIVE = 0x0020, /* object is in evheap */
366 DN_F_DLINE = 0x0040, /* object is a delay line */
367 DN_DEL_SAFE = 0x0080, /* delete a queue only if no longer needed
368 * by scheduler */
369 DN_QHT_IS_Q = 0x0100, /* in flowset, qht is a single queue */
370 };
371
372 /*
373 * Packets processed by dummynet have an mbuf tag associated with
374 * them that carries their dummynet state.
375 * Outside dummynet, only the 'rule' field is relevant, and it must
376 * be at the beginning of the structure.
377 */
378 struct dn_pkt_tag {
379 struct ipfw_rule_ref rule; /* matching rule */
380
381 /* second part, dummynet specific */
382 int dn_dir; /* action when packet comes out.*/
383 /* see ip_fw_private.h */
384 uint64_t output_time; /* when the pkt is due for delivery*/
385 struct ifnet *ifp; /* interface, for ip_output */
386 struct _ip6dn_args ip6opt; /* XXX ipv6 options */
387 uint16_t iphdr_off; /* IP header offset for mtodo() */
388 };
389
390 extern struct dn_parms dn_cfg;
391 //VNET_DECLARE(struct dn_parms, _base_dn_cfg);
392 //#define dn_cfg VNET(_base_dn_cfg)
393
394 int dummynet_io(struct mbuf **, int , struct ip_fw_args *);
395 void dummynet_task(void *context, int pending);
396 void dn_reschedule(void);
397 struct dn_pkt_tag * dn_tag_get(struct mbuf *m);
398
399 struct dn_queue *ipdn_q_find(struct dn_fsk *, struct dn_sch_inst *,
400 struct ipfw_flow_id *);
401 struct dn_sch_inst *ipdn_si_find(struct dn_schk *, struct ipfw_flow_id *);
402
403 /*
404 * copy_range is a template for requests for ranges of pipes/queues/scheds.
405 * The number of ranges is variable and can be derived by o.len.
406 * As a default, we use a small number of entries so that the struct
407 * fits easily on the stack and is sufficient for most common requests.
408 */
409 #define DEFAULT_RANGES 5
410 struct copy_range {
411 struct dn_id o;
412 uint32_t r[ 2 * DEFAULT_RANGES ];
413 };
414
415 struct copy_args {
416 char **start;
417 char *end;
418 int flags;
419 int type;
420 struct copy_range *extra; /* extra filtering */
421 };
422
423 struct sockopt;
424 int ip_dummynet_compat(struct sockopt *sopt);
425 int dummynet_get(struct sockopt *sopt, void **compat);
426 int dn_c_copy_q (void *_ni, void *arg);
427 int dn_c_copy_pipe(struct dn_schk *s, struct copy_args *a, int nq);
428 int dn_c_copy_fs(struct dn_fsk *f, struct copy_args *a, int nq);
429 int dn_compat_copy_queue(struct copy_args *a, void *_o);
430 int dn_compat_copy_pipe(struct copy_args *a, void *_o);
431 int copy_data_helper_compat(void *_o, void *_arg);
432 int dn_compat_calc_size(void);
433 int do_config(void *p, int l);
434
435 /* function to drain idle object */
436 void dn_drain_scheduler(void);
437 void dn_drain_queue(void);
438
439 #ifdef NEW_AQM
440 int ecn_mark(struct mbuf* m);
441
442 /* moved from ip_dn_io.c to here to be available for AQMs modules*/
443 static inline void
mq_append(struct mq * q,struct mbuf * m)444 mq_append(struct mq *q, struct mbuf *m)
445 {
446 #ifdef USERSPACE
447 // buffers from netmap need to be copied
448 // XXX note that the routine is not expected to fail
449 ND("append %p to %p", m, q);
450 if (m->m_flags & M_STACK) {
451 struct mbuf *m_new;
452 void *p;
453 int l, ofs;
454
455 ofs = m->m_data - m->__m_extbuf;
456 // XXX allocate
457 MGETHDR(m_new, M_NOWAIT, MT_DATA);
458 ND("*** WARNING, volatile buf %p ext %p %d dofs %d m_new %p",
459 m, m->__m_extbuf, m->__m_extlen, ofs, m_new);
460 p = m_new->__m_extbuf; /* new pointer */
461 l = m_new->__m_extlen; /* new len */
462 if (l <= m->__m_extlen) {
463 panic("extlen too large");
464 }
465
466 *m_new = *m; // copy
467 m_new->m_flags &= ~M_STACK;
468 m_new->__m_extbuf = p; // point to new buffer
469 _pkt_copy(m->__m_extbuf, p, m->__m_extlen);
470 m_new->m_data = p + ofs;
471 m = m_new;
472 }
473 #endif /* USERSPACE */
474 if (q->head == NULL)
475 q->head = m;
476 else
477 q->tail->m_nextpkt = m;
478 q->count++;
479 q->tail = m;
480 m->m_nextpkt = NULL;
481 }
482 #endif /* NEW_AQM */
483
484 #endif /* _IP_DN_PRIVATE_H */
485