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fs: check for statfs overflow
[linux-2.6/mini2440.git] / net / sched / sch_hfsc.c
blob0ae7d19dcba8c0e0906577832b5df293e9a0641e
1 /*
2 * Copyright (c) 2003 Patrick McHardy, <kaber@trash.net>
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version 2
7 * of the License, or (at your option) any later version.
8 *
9 * 2003-10-17 - Ported from altq
10 */
11 /*
12 * Copyright (c) 1997-1999 Carnegie Mellon University. All Rights Reserved.
13 *
14 * Permission to use, copy, modify, and distribute this software and
15 * its documentation is hereby granted (including for commercial or
16 * for-profit use), provided that both the copyright notice and this
17 * permission notice appear in all copies of the software, derivative
18 * works, or modified versions, and any portions thereof.
19 *
20 * THIS SOFTWARE IS EXPERIMENTAL AND IS KNOWN TO HAVE BUGS, SOME OF
21 * WHICH MAY HAVE SERIOUS CONSEQUENCES. CARNEGIE MELLON PROVIDES THIS
22 * SOFTWARE IN ITS ``AS IS'' CONDITION, AND ANY EXPRESS OR IMPLIED
23 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
25 * DISCLAIMED. IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
28 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
29 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
30 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
32 * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
33 * DAMAGE.
34 *
35 * Carnegie Mellon encourages (but does not require) users of this
36 * software to return any improvements or extensions that they make,
37 * and to grant Carnegie Mellon the rights to redistribute these
38 * changes without encumbrance.
39 */
40 /*
41 * H-FSC is described in Proceedings of SIGCOMM'97,
42 * "A Hierarchical Fair Service Curve Algorithm for Link-Sharing,
43 * Real-Time and Priority Service"
44 * by Ion Stoica, Hui Zhang, and T. S. Eugene Ng.
45 *
46 * Oleg Cherevko <olwi@aq.ml.com.ua> added the upperlimit for link-sharing.
47 * when a class has an upperlimit, the fit-time is computed from the
48 * upperlimit service curve. the link-sharing scheduler does not schedule
49 * a class whose fit-time exceeds the current time.
50 */
51
52 #include <linux/kernel.h>
53 #include <linux/module.h>
54 #include <linux/types.h>
55 #include <linux/errno.h>
56 #include <linux/compiler.h>
57 #include <linux/spinlock.h>
58 #include <linux/skbuff.h>
59 #include <linux/string.h>
60 #include <linux/slab.h>
61 #include <linux/list.h>
62 #include <linux/rbtree.h>
63 #include <linux/init.h>
64 #include <linux/rtnetlink.h>
65 #include <linux/pkt_sched.h>
66 #include <net/netlink.h>
67 #include <net/pkt_sched.h>
68 #include <net/pkt_cls.h>
69 #include <asm/div64.h>
70
71 /*
72 * kernel internal service curve representation:
73 * coordinates are given by 64 bit unsigned integers.
74 * x-axis: unit is clock count.
75 * y-axis: unit is byte.
76 *
77 * The service curve parameters are converted to the internal
78 * representation. The slope values are scaled to avoid overflow.
79 * the inverse slope values as well as the y-projection of the 1st
80 * segment are kept in order to to avoid 64-bit divide operations
81 * that are expensive on 32-bit architectures.
82 */
83
84 struct internal_sc
85 {
86 u64 sm1; /* scaled slope of the 1st segment */
87 u64 ism1; /* scaled inverse-slope of the 1st segment */
88 u64 dx; /* the x-projection of the 1st segment */
89 u64 dy; /* the y-projection of the 1st segment */
90 u64 sm2; /* scaled slope of the 2nd segment */
91 u64 ism2; /* scaled inverse-slope of the 2nd segment */
92 };
93
94 /* runtime service curve */
95 struct runtime_sc
96 {
97 u64 x; /* current starting position on x-axis */
98 u64 y; /* current starting position on y-axis */
99 u64 sm1; /* scaled slope of the 1st segment */
100 u64 ism1; /* scaled inverse-slope of the 1st segment */
101 u64 dx; /* the x-projection of the 1st segment */
102 u64 dy; /* the y-projection of the 1st segment */
103 u64 sm2; /* scaled slope of the 2nd segment */
104 u64 ism2; /* scaled inverse-slope of the 2nd segment */
105 };
106
107 enum hfsc_class_flags
108 {
109 HFSC_RSC = 0x1,
110 HFSC_FSC = 0x2,
111 HFSC_USC = 0x4
112 };
113
114 struct hfsc_class
115 {
116 struct Qdisc_class_common cl_common;
117 unsigned int refcnt; /* usage count */
118
119 struct gnet_stats_basic bstats;
120 struct gnet_stats_queue qstats;
121 struct gnet_stats_rate_est rate_est;
122 unsigned int level; /* class level in hierarchy */
123 struct tcf_proto *filter_list; /* filter list */
124 unsigned int filter_cnt; /* filter count */
125
126 struct hfsc_sched *sched; /* scheduler data */
127 struct hfsc_class *cl_parent; /* parent class */
128 struct list_head siblings; /* sibling classes */
129 struct list_head children; /* child classes */
130 struct Qdisc *qdisc; /* leaf qdisc */
131
132 struct rb_node el_node; /* qdisc's eligible tree member */
133 struct rb_root vt_tree; /* active children sorted by cl_vt */
134 struct rb_node vt_node; /* parent's vt_tree member */
135 struct rb_root cf_tree; /* active children sorted by cl_f */
136 struct rb_node cf_node; /* parent's cf_heap member */
137 struct list_head dlist; /* drop list member */
138
139 u64 cl_total; /* total work in bytes */
140 u64 cl_cumul; /* cumulative work in bytes done by
141 real-time criteria */
142
143 u64 cl_d; /* deadline*/
144 u64 cl_e; /* eligible time */
145 u64 cl_vt; /* virtual time */
146 u64 cl_f; /* time when this class will fit for
147 link-sharing, max(myf, cfmin) */
148 u64 cl_myf; /* my fit-time (calculated from this
149 class's own upperlimit curve) */
150 u64 cl_myfadj; /* my fit-time adjustment (to cancel
151 history dependence) */
152 u64 cl_cfmin; /* earliest children's fit-time (used
153 with cl_myf to obtain cl_f) */
154 u64 cl_cvtmin; /* minimal virtual time among the
155 children fit for link-sharing
156 (monotonic within a period) */
157 u64 cl_vtadj; /* intra-period cumulative vt
158 adjustment */
159 u64 cl_vtoff; /* inter-period cumulative vt offset */
160 u64 cl_cvtmax; /* max child's vt in the last period */
161 u64 cl_cvtoff; /* cumulative cvtmax of all periods */
162 u64 cl_pcvtoff; /* parent's cvtoff at initialization
163 time */
164
165 struct internal_sc cl_rsc; /* internal real-time service curve */
166 struct internal_sc cl_fsc; /* internal fair service curve */
167 struct internal_sc cl_usc; /* internal upperlimit service curve */
168 struct runtime_sc cl_deadline; /* deadline curve */
169 struct runtime_sc cl_eligible; /* eligible curve */
170 struct runtime_sc cl_virtual; /* virtual curve */
171 struct runtime_sc cl_ulimit; /* upperlimit curve */
172
173 unsigned long cl_flags; /* which curves are valid */
174 unsigned long cl_vtperiod; /* vt period sequence number */
175 unsigned long cl_parentperiod;/* parent's vt period sequence number*/
176 unsigned long cl_nactive; /* number of active children */
177 };
178
179 struct hfsc_sched
180 {
181 u16 defcls; /* default class id */
182 struct hfsc_class root; /* root class */
183 struct Qdisc_class_hash clhash; /* class hash */
184 struct rb_root eligible; /* eligible tree */
185 struct list_head droplist; /* active leaf class list (for
186 dropping) */
187 struct sk_buff_head requeue; /* requeued packet */
188 struct qdisc_watchdog watchdog; /* watchdog timer */
189 };
190
191 #define HT_INFINITY 0xffffffffffffffffULL /* infinite time value */
192
193
194 /*
195 * eligible tree holds backlogged classes being sorted by their eligible times.
196 * there is one eligible tree per hfsc instance.
197 */
198
199 static void
200 eltree_insert(struct hfsc_class *cl)
201 {
202 struct rb_node **p = &cl->sched->eligible.rb_node;
203 struct rb_node *parent = NULL;
204 struct hfsc_class *cl1;
205
206 while (*p != NULL) {
207 parent = *p;
208 cl1 = rb_entry(parent, struct hfsc_class, el_node);
209 if (cl->cl_e >= cl1->cl_e)
210 p = &parent->rb_right;
211 else
212 p = &parent->rb_left;
213 }
214 rb_link_node(&cl->el_node, parent, p);
215 rb_insert_color(&cl->el_node, &cl->sched->eligible);
216 }
217
218 static inline void
219 eltree_remove(struct hfsc_class *cl)
220 {
221 rb_erase(&cl->el_node, &cl->sched->eligible);
222 }
223
224 static inline void
225 eltree_update(struct hfsc_class *cl)
226 {
227 eltree_remove(cl);
228 eltree_insert(cl);
229 }
230
231 /* find the class with the minimum deadline among the eligible classes */
232 static inline struct hfsc_class *
233 eltree_get_mindl(struct hfsc_sched *q, u64 cur_time)
234 {
235 struct hfsc_class *p, *cl = NULL;
236 struct rb_node *n;
237
238 for (n = rb_first(&q->eligible); n != NULL; n = rb_next(n)) {
239 p = rb_entry(n, struct hfsc_class, el_node);
240 if (p->cl_e > cur_time)
241 break;
242 if (cl == NULL || p->cl_d < cl->cl_d)
243 cl = p;
244 }
245 return cl;
246 }
247
248 /* find the class with minimum eligible time among the eligible classes */
249 static inline struct hfsc_class *
250 eltree_get_minel(struct hfsc_sched *q)
251 {
252 struct rb_node *n;
253
254 n = rb_first(&q->eligible);
255 if (n == NULL)
256 return NULL;
257 return rb_entry(n, struct hfsc_class, el_node);
258 }
259
260 /*
261 * vttree holds holds backlogged child classes being sorted by their virtual
262 * time. each intermediate class has one vttree.
263 */
264 static void
265 vttree_insert(struct hfsc_class *cl)
266 {
267 struct rb_node **p = &cl->cl_parent->vt_tree.rb_node;
268 struct rb_node *parent = NULL;
269 struct hfsc_class *cl1;
270
271 while (*p != NULL) {
272 parent = *p;
273 cl1 = rb_entry(parent, struct hfsc_class, vt_node);
274 if (cl->cl_vt >= cl1->cl_vt)
275 p = &parent->rb_right;
276 else
277 p = &parent->rb_left;
278 }
279 rb_link_node(&cl->vt_node, parent, p);
280 rb_insert_color(&cl->vt_node, &cl->cl_parent->vt_tree);
281 }
282
283 static inline void
284 vttree_remove(struct hfsc_class *cl)
285 {
286 rb_erase(&cl->vt_node, &cl->cl_parent->vt_tree);
287 }
288
289 static inline void
290 vttree_update(struct hfsc_class *cl)
291 {
292 vttree_remove(cl);
293 vttree_insert(cl);
294 }
295
296 static inline struct hfsc_class *
297 vttree_firstfit(struct hfsc_class *cl, u64 cur_time)
298 {
299 struct hfsc_class *p;
300 struct rb_node *n;
301
302 for (n = rb_first(&cl->vt_tree); n != NULL; n = rb_next(n)) {
303 p = rb_entry(n, struct hfsc_class, vt_node);
304 if (p->cl_f <= cur_time)
305 return p;
306 }
307 return NULL;
308 }
309
310 /*
311 * get the leaf class with the minimum vt in the hierarchy
312 */
313 static struct hfsc_class *
314 vttree_get_minvt(struct hfsc_class *cl, u64 cur_time)
315 {
316 /* if root-class's cfmin is bigger than cur_time nothing to do */
317 if (cl->cl_cfmin > cur_time)
318 return NULL;
319
320 while (cl->level > 0) {
321 cl = vttree_firstfit(cl, cur_time);
322 if (cl == NULL)
323 return NULL;
324 /*
325 * update parent's cl_cvtmin.
326 */
327 if (cl->cl_parent->cl_cvtmin < cl->cl_vt)
328 cl->cl_parent->cl_cvtmin = cl->cl_vt;
329 }
330 return cl;
331 }
332
333 static void
334 cftree_insert(struct hfsc_class *cl)
335 {
336 struct rb_node **p = &cl->cl_parent->cf_tree.rb_node;
337 struct rb_node *parent = NULL;
338 struct hfsc_class *cl1;
339
340 while (*p != NULL) {
341 parent = *p;
342 cl1 = rb_entry(parent, struct hfsc_class, cf_node);
343 if (cl->cl_f >= cl1->cl_f)
344 p = &parent->rb_right;
345 else
346 p = &parent->rb_left;
347 }
348 rb_link_node(&cl->cf_node, parent, p);
349 rb_insert_color(&cl->cf_node, &cl->cl_parent->cf_tree);
350 }
351
352 static inline void
353 cftree_remove(struct hfsc_class *cl)
354 {
355 rb_erase(&cl->cf_node, &cl->cl_parent->cf_tree);
356 }
357
358 static inline void
359 cftree_update(struct hfsc_class *cl)
360 {
361 cftree_remove(cl);
362 cftree_insert(cl);
363 }
364
365 /*
366 * service curve support functions
367 *
368 * external service curve parameters
369 * m: bps
370 * d: us
371 * internal service curve parameters
372 * sm: (bytes/psched_us) << SM_SHIFT
373 * ism: (psched_us/byte) << ISM_SHIFT
374 * dx: psched_us
375 *
376 * The clock source resolution with ktime is 1.024us.
377 *
378 * sm and ism are scaled in order to keep effective digits.
379 * SM_SHIFT and ISM_SHIFT are selected to keep at least 4 effective
380 * digits in decimal using the following table.
381 *
382 * bits/sec 100Kbps 1Mbps 10Mbps 100Mbps 1Gbps
383 * ------------+-------------------------------------------------------
384 * bytes/1.024us 12.8e-3 128e-3 1280e-3 12800e-3 128000e-3
385 *
386 * 1.024us/byte 78.125 7.8125 0.78125 0.078125 0.0078125
387 */
388 #define SM_SHIFT 20
389 #define ISM_SHIFT 18
390
391 #define SM_MASK ((1ULL << SM_SHIFT) - 1)
392 #define ISM_MASK ((1ULL << ISM_SHIFT) - 1)
393
394 static inline u64
395 seg_x2y(u64 x, u64 sm)
396 {
397 u64 y;
398
399 /*
400 * compute
401 * y = x * sm >> SM_SHIFT
402 * but divide it for the upper and lower bits to avoid overflow
403 */
404 y = (x >> SM_SHIFT) * sm + (((x & SM_MASK) * sm) >> SM_SHIFT);
405 return y;
406 }
407
408 static inline u64
409 seg_y2x(u64 y, u64 ism)
410 {
411 u64 x;
412
413 if (y == 0)
414 x = 0;
415 else if (ism == HT_INFINITY)
416 x = HT_INFINITY;
417 else {
418 x = (y >> ISM_SHIFT) * ism
419 + (((y & ISM_MASK) * ism) >> ISM_SHIFT);
420 }
421 return x;
422 }
423
424 /* Convert m (bps) into sm (bytes/psched us) */
425 static u64
426 m2sm(u32 m)
427 {
428 u64 sm;
429
430 sm = ((u64)m << SM_SHIFT);
431 sm += PSCHED_TICKS_PER_SEC - 1;
432 do_div(sm, PSCHED_TICKS_PER_SEC);
433 return sm;
434 }
435
436 /* convert m (bps) into ism (psched us/byte) */
437 static u64
438 m2ism(u32 m)
439 {
440 u64 ism;
441
442 if (m == 0)
443 ism = HT_INFINITY;
444 else {
445 ism = ((u64)PSCHED_TICKS_PER_SEC << ISM_SHIFT);
446 ism += m - 1;
447 do_div(ism, m);
448 }
449 return ism;
450 }
451
452 /* convert d (us) into dx (psched us) */
453 static u64
454 d2dx(u32 d)
455 {
456 u64 dx;
457
458 dx = ((u64)d * PSCHED_TICKS_PER_SEC);
459 dx += USEC_PER_SEC - 1;
460 do_div(dx, USEC_PER_SEC);
461 return dx;
462 }
463
464 /* convert sm (bytes/psched us) into m (bps) */
465 static u32
466 sm2m(u64 sm)
467 {
468 u64 m;
469
470 m = (sm * PSCHED_TICKS_PER_SEC) >> SM_SHIFT;
471 return (u32)m;
472 }
473
474 /* convert dx (psched us) into d (us) */
475 static u32
476 dx2d(u64 dx)
477 {
478 u64 d;
479
480 d = dx * USEC_PER_SEC;
481 do_div(d, PSCHED_TICKS_PER_SEC);
482 return (u32)d;
483 }
484
485 static void
486 sc2isc(struct tc_service_curve *sc, struct internal_sc *isc)
487 {
488 isc->sm1 = m2sm(sc->m1);
489 isc->ism1 = m2ism(sc->m1);
490 isc->dx = d2dx(sc->d);
491 isc->dy = seg_x2y(isc->dx, isc->sm1);
492 isc->sm2 = m2sm(sc->m2);
493 isc->ism2 = m2ism(sc->m2);
494 }
495
496 /*
497 * initialize the runtime service curve with the given internal
498 * service curve starting at (x, y).
499 */
500 static void
501 rtsc_init(struct runtime_sc *rtsc, struct internal_sc *isc, u64 x, u64 y)
502 {
503 rtsc->x = x;
504 rtsc->y = y;
505 rtsc->sm1 = isc->sm1;
506 rtsc->ism1 = isc->ism1;
507 rtsc->dx = isc->dx;
508 rtsc->dy = isc->dy;
509 rtsc->sm2 = isc->sm2;
510 rtsc->ism2 = isc->ism2;
511 }
512
513 /*
514 * calculate the y-projection of the runtime service curve by the
515 * given x-projection value
516 */
517 static u64
518 rtsc_y2x(struct runtime_sc *rtsc, u64 y)
519 {
520 u64 x;
521
522 if (y < rtsc->y)
523 x = rtsc->x;
524 else if (y <= rtsc->y + rtsc->dy) {
525 /* x belongs to the 1st segment */
526 if (rtsc->dy == 0)
527 x = rtsc->x + rtsc->dx;
528 else
529 x = rtsc->x + seg_y2x(y - rtsc->y, rtsc->ism1);
530 } else {
531 /* x belongs to the 2nd segment */
532 x = rtsc->x + rtsc->dx
533 + seg_y2x(y - rtsc->y - rtsc->dy, rtsc->ism2);
534 }
535 return x;
536 }
537
538 static u64
539 rtsc_x2y(struct runtime_sc *rtsc, u64 x)
540 {
541 u64 y;
542
543 if (x <= rtsc->x)
544 y = rtsc->y;
545 else if (x <= rtsc->x + rtsc->dx)
546 /* y belongs to the 1st segment */
547 y = rtsc->y + seg_x2y(x - rtsc->x, rtsc->sm1);
548 else
549 /* y belongs to the 2nd segment */
550 y = rtsc->y + rtsc->dy
551 + seg_x2y(x - rtsc->x - rtsc->dx, rtsc->sm2);
552 return y;
553 }
554
555 /*
556 * update the runtime service curve by taking the minimum of the current
557 * runtime service curve and the service curve starting at (x, y).
558 */
559 static void
560 rtsc_min(struct runtime_sc *rtsc, struct internal_sc *isc, u64 x, u64 y)
561 {
562 u64 y1, y2, dx, dy;
563 u32 dsm;
564
565 if (isc->sm1 <= isc->sm2) {
566 /* service curve is convex */
567 y1 = rtsc_x2y(rtsc, x);
568 if (y1 < y)
569 /* the current rtsc is smaller */
570 return;
571 rtsc->x = x;
572 rtsc->y = y;
573 return;
574 }
575
576 /*
577 * service curve is concave
578 * compute the two y values of the current rtsc
579 * y1: at x
580 * y2: at (x + dx)
581 */
582 y1 = rtsc_x2y(rtsc, x);
583 if (y1 <= y) {
584 /* rtsc is below isc, no change to rtsc */
585 return;
586 }
587
588 y2 = rtsc_x2y(rtsc, x + isc->dx);
589 if (y2 >= y + isc->dy) {
590 /* rtsc is above isc, replace rtsc by isc */
591 rtsc->x = x;
592 rtsc->y = y;
593 rtsc->dx = isc->dx;
594 rtsc->dy = isc->dy;
595 return;
596 }
597
598 /*
599 * the two curves intersect
600 * compute the offsets (dx, dy) using the reverse
601 * function of seg_x2y()
602 * seg_x2y(dx, sm1) == seg_x2y(dx, sm2) + (y1 - y)
603 */
604 dx = (y1 - y) << SM_SHIFT;
605 dsm = isc->sm1 - isc->sm2;
606 do_div(dx, dsm);
607 /*
608 * check if (x, y1) belongs to the 1st segment of rtsc.
609 * if so, add the offset.
610 */
611 if (rtsc->x + rtsc->dx > x)
612 dx += rtsc->x + rtsc->dx - x;
613 dy = seg_x2y(dx, isc->sm1);
614
615 rtsc->x = x;
616 rtsc->y = y;
617 rtsc->dx = dx;
618 rtsc->dy = dy;
619 return;
620 }
621
622 static void
623 init_ed(struct hfsc_class *cl, unsigned int next_len)
624 {
625 u64 cur_time = psched_get_time();
626
627 /* update the deadline curve */
628 rtsc_min(&cl->cl_deadline, &cl->cl_rsc, cur_time, cl->cl_cumul);
629
630 /*
631 * update the eligible curve.
632 * for concave, it is equal to the deadline curve.
633 * for convex, it is a linear curve with slope m2.
634 */
635 cl->cl_eligible = cl->cl_deadline;
636 if (cl->cl_rsc.sm1 <= cl->cl_rsc.sm2) {
637 cl->cl_eligible.dx = 0;
638 cl->cl_eligible.dy = 0;
639 }
640
641 /* compute e and d */
642 cl->cl_e = rtsc_y2x(&cl->cl_eligible, cl->cl_cumul);
643 cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
644
645 eltree_insert(cl);
646 }
647
648 static void
649 update_ed(struct hfsc_class *cl, unsigned int next_len)
650 {
651 cl->cl_e = rtsc_y2x(&cl->cl_eligible, cl->cl_cumul);
652 cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
653
654 eltree_update(cl);
655 }
656
657 static inline void
658 update_d(struct hfsc_class *cl, unsigned int next_len)
659 {
660 cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
661 }
662
663 static inline void
664 update_cfmin(struct hfsc_class *cl)
665 {
666 struct rb_node *n = rb_first(&cl->cf_tree);
667 struct hfsc_class *p;
668
669 if (n == NULL) {
670 cl->cl_cfmin = 0;
671 return;
672 }
673 p = rb_entry(n, struct hfsc_class, cf_node);
674 cl->cl_cfmin = p->cl_f;
675 }
676
677 static void
678 init_vf(struct hfsc_class *cl, unsigned int len)
679 {
680 struct hfsc_class *max_cl;
681 struct rb_node *n;
682 u64 vt, f, cur_time;
683 int go_active;
684
685 cur_time = 0;
686 go_active = 1;
687 for (; cl->cl_parent != NULL; cl = cl->cl_parent) {
688 if (go_active && cl->cl_nactive++ == 0)
689 go_active = 1;
690 else
691 go_active = 0;
692
693 if (go_active) {
694 n = rb_last(&cl->cl_parent->vt_tree);
695 if (n != NULL) {
696 max_cl = rb_entry(n, struct hfsc_class,vt_node);
697 /*
698 * set vt to the average of the min and max
699 * classes. if the parent's period didn't
700 * change, don't decrease vt of the class.
701 */
702 vt = max_cl->cl_vt;
703 if (cl->cl_parent->cl_cvtmin != 0)
704 vt = (cl->cl_parent->cl_cvtmin + vt)/2;
705
706 if (cl->cl_parent->cl_vtperiod !=
707 cl->cl_parentperiod || vt > cl->cl_vt)
708 cl->cl_vt = vt;
709 } else {
710 /*
711 * first child for a new parent backlog period.
712 * add parent's cvtmax to cvtoff to make a new
713 * vt (vtoff + vt) larger than the vt in the
714 * last period for all children.
715 */
716 vt = cl->cl_parent->cl_cvtmax;
717 cl->cl_parent->cl_cvtoff += vt;
718 cl->cl_parent->cl_cvtmax = 0;
719 cl->cl_parent->cl_cvtmin = 0;
720 cl->cl_vt = 0;
721 }
722
723 cl->cl_vtoff = cl->cl_parent->cl_cvtoff -
724 cl->cl_pcvtoff;
725
726 /* update the virtual curve */
727 vt = cl->cl_vt + cl->cl_vtoff;
728 rtsc_min(&cl->cl_virtual, &cl->cl_fsc, vt,
729 cl->cl_total);
730 if (cl->cl_virtual.x == vt) {
731 cl->cl_virtual.x -= cl->cl_vtoff;
732 cl->cl_vtoff = 0;
733 }
734 cl->cl_vtadj = 0;
735
736 cl->cl_vtperiod++; /* increment vt period */
737 cl->cl_parentperiod = cl->cl_parent->cl_vtperiod;
738 if (cl->cl_parent->cl_nactive == 0)
739 cl->cl_parentperiod++;
740 cl->cl_f = 0;
741
742 vttree_insert(cl);
743 cftree_insert(cl);
744
745 if (cl->cl_flags & HFSC_USC) {
746 /* class has upper limit curve */
747 if (cur_time == 0)
748 cur_time = psched_get_time();
749
750 /* update the ulimit curve */
751 rtsc_min(&cl->cl_ulimit, &cl->cl_usc, cur_time,
752 cl->cl_total);
753 /* compute myf */
754 cl->cl_myf = rtsc_y2x(&cl->cl_ulimit,
755 cl->cl_total);
756 cl->cl_myfadj = 0;
757 }
758 }
759
760 f = max(cl->cl_myf, cl->cl_cfmin);
761 if (f != cl->cl_f) {
762 cl->cl_f = f;
763 cftree_update(cl);
764 update_cfmin(cl->cl_parent);
765 }
766 }
767 }
768
769 static void
770 update_vf(struct hfsc_class *cl, unsigned int len, u64 cur_time)
771 {
772 u64 f; /* , myf_bound, delta; */
773 int go_passive = 0;
774
775 if (cl->qdisc->q.qlen == 0 && cl->cl_flags & HFSC_FSC)
776 go_passive = 1;
777
778 for (; cl->cl_parent != NULL; cl = cl->cl_parent) {
779 cl->cl_total += len;
780
781 if (!(cl->cl_flags & HFSC_FSC) || cl->cl_nactive == 0)
782 continue;
783
784 if (go_passive && --cl->cl_nactive == 0)
785 go_passive = 1;
786 else
787 go_passive = 0;
788
789 if (go_passive) {
790 /* no more active child, going passive */
791
792 /* update cvtmax of the parent class */
793 if (cl->cl_vt > cl->cl_parent->cl_cvtmax)
794 cl->cl_parent->cl_cvtmax = cl->cl_vt;
795
796 /* remove this class from the vt tree */
797 vttree_remove(cl);
798
799 cftree_remove(cl);
800 update_cfmin(cl->cl_parent);
801
802 continue;
803 }
804
805 /*
806 * update vt and f
807 */
808 cl->cl_vt = rtsc_y2x(&cl->cl_virtual, cl->cl_total)
809 - cl->cl_vtoff + cl->cl_vtadj;
810
811 /*
812 * if vt of the class is smaller than cvtmin,
813 * the class was skipped in the past due to non-fit.
814 * if so, we need to adjust vtadj.
815 */
816 if (cl->cl_vt < cl->cl_parent->cl_cvtmin) {
817 cl->cl_vtadj += cl->cl_parent->cl_cvtmin - cl->cl_vt;
818 cl->cl_vt = cl->cl_parent->cl_cvtmin;
819 }
820
821 /* update the vt tree */
822 vttree_update(cl);
823
824 if (cl->cl_flags & HFSC_USC) {
825 cl->cl_myf = cl->cl_myfadj + rtsc_y2x(&cl->cl_ulimit,
826 cl->cl_total);
827 #if 0
828 /*
829 * This code causes classes to stay way under their
830 * limit when multiple classes are used at gigabit
831 * speed. needs investigation. -kaber
832 */
833 /*
834 * if myf lags behind by more than one clock tick
835 * from the current time, adjust myfadj to prevent
836 * a rate-limited class from going greedy.
837 * in a steady state under rate-limiting, myf
838 * fluctuates within one clock tick.
839 */
840 myf_bound = cur_time - PSCHED_JIFFIE2US(1);
841 if (cl->cl_myf < myf_bound) {
842 delta = cur_time - cl->cl_myf;
843 cl->cl_myfadj += delta;
844 cl->cl_myf += delta;
845 }
846 #endif
847 }
848
849 f = max(cl->cl_myf, cl->cl_cfmin);
850 if (f != cl->cl_f) {
851 cl->cl_f = f;
852 cftree_update(cl);
853 update_cfmin(cl->cl_parent);
854 }
855 }
856 }
857
858 static void
859 set_active(struct hfsc_class *cl, unsigned int len)
860 {
861 if (cl->cl_flags & HFSC_RSC)
862 init_ed(cl, len);
863 if (cl->cl_flags & HFSC_FSC)
864 init_vf(cl, len);
865
866 list_add_tail(&cl->dlist, &cl->sched->droplist);
867 }
868
869 static void
870 set_passive(struct hfsc_class *cl)
871 {
872 if (cl->cl_flags & HFSC_RSC)
873 eltree_remove(cl);
874
875 list_del(&cl->dlist);
876
877 /*
878 * vttree is now handled in update_vf() so that update_vf(cl, 0, 0)
879 * needs to be called explicitly to remove a class from vttree.
880 */
881 }
882
883 /*
884 * hack to get length of first packet in queue.
885 */
886 static unsigned int
887 qdisc_peek_len(struct Qdisc *sch)
888 {
889 struct sk_buff *skb;
890 unsigned int len;
891
892 skb = sch->dequeue(sch);
893 if (skb == NULL) {
894 if (net_ratelimit())
895 printk("qdisc_peek_len: non work-conserving qdisc ?\n");
896 return 0;
897 }
898 len = qdisc_pkt_len(skb);
899 if (unlikely(sch->ops->requeue(skb, sch) != NET_XMIT_SUCCESS)) {
900 if (net_ratelimit())
901 printk("qdisc_peek_len: failed to requeue\n");
902 qdisc_tree_decrease_qlen(sch, 1);
903 return 0;
904 }
905 return len;
906 }
907
908 static void
909 hfsc_purge_queue(struct Qdisc *sch, struct hfsc_class *cl)
910 {
911 unsigned int len = cl->qdisc->q.qlen;
912
913 qdisc_reset(cl->qdisc);
914 qdisc_tree_decrease_qlen(cl->qdisc, len);
915 }
916
917 static void
918 hfsc_adjust_levels(struct hfsc_class *cl)
919 {
920 struct hfsc_class *p;
921 unsigned int level;
922
923 do {
924 level = 0;
925 list_for_each_entry(p, &cl->children, siblings) {
926 if (p->level >= level)
927 level = p->level + 1;
928 }
929 cl->level = level;
930 } while ((cl = cl->cl_parent) != NULL);
931 }
932
933 static inline struct hfsc_class *
934 hfsc_find_class(u32 classid, struct Qdisc *sch)
935 {
936 struct hfsc_sched *q = qdisc_priv(sch);
937 struct Qdisc_class_common *clc;
938
939 clc = qdisc_class_find(&q->clhash, classid);
940 if (clc == NULL)
941 return NULL;
942 return container_of(clc, struct hfsc_class, cl_common);
943 }
944
945 static void
946 hfsc_change_rsc(struct hfsc_class *cl, struct tc_service_curve *rsc,
947 u64 cur_time)
948 {
949 sc2isc(rsc, &cl->cl_rsc);
950 rtsc_init(&cl->cl_deadline, &cl->cl_rsc, cur_time, cl->cl_cumul);
951 cl->cl_eligible = cl->cl_deadline;
952 if (cl->cl_rsc.sm1 <= cl->cl_rsc.sm2) {
953 cl->cl_eligible.dx = 0;
954 cl->cl_eligible.dy = 0;
955 }
956 cl->cl_flags |= HFSC_RSC;
957 }
958
959 static void
960 hfsc_change_fsc(struct hfsc_class *cl, struct tc_service_curve *fsc)
961 {
962 sc2isc(fsc, &cl->cl_fsc);
963 rtsc_init(&cl->cl_virtual, &cl->cl_fsc, cl->cl_vt, cl->cl_total);
964 cl->cl_flags |= HFSC_FSC;
965 }
966
967 static void
968 hfsc_change_usc(struct hfsc_class *cl, struct tc_service_curve *usc,
969 u64 cur_time)
970 {
971 sc2isc(usc, &cl->cl_usc);
972 rtsc_init(&cl->cl_ulimit, &cl->cl_usc, cur_time, cl->cl_total);
973 cl->cl_flags |= HFSC_USC;
974 }
975
976 static const struct nla_policy hfsc_policy[TCA_HFSC_MAX + 1] = {
977 [TCA_HFSC_RSC] = { .len = sizeof(struct tc_service_curve) },
978 [TCA_HFSC_FSC] = { .len = sizeof(struct tc_service_curve) },
979 [TCA_HFSC_USC] = { .len = sizeof(struct tc_service_curve) },
980 };
981
982 static int
983 hfsc_change_class(struct Qdisc *sch, u32 classid, u32 parentid,
984 struct nlattr **tca, unsigned long *arg)
985 {
986 struct hfsc_sched *q = qdisc_priv(sch);
987 struct hfsc_class *cl = (struct hfsc_class *)*arg;
988 struct hfsc_class *parent = NULL;
989 struct nlattr *opt = tca[TCA_OPTIONS];
990 struct nlattr *tb[TCA_HFSC_MAX + 1];
991 struct tc_service_curve *rsc = NULL, *fsc = NULL, *usc = NULL;
992 u64 cur_time;
993 int err;
994
995 if (opt == NULL)
996 return -EINVAL;
997
998 err = nla_parse_nested(tb, TCA_HFSC_MAX, opt, hfsc_policy);
999 if (err < 0)
1000 return err;
1001
1002 if (tb[TCA_HFSC_RSC]) {
1003 rsc = nla_data(tb[TCA_HFSC_RSC]);
1004 if (rsc->m1 == 0 && rsc->m2 == 0)
1005 rsc = NULL;
1006 }
1007
1008 if (tb[TCA_HFSC_FSC]) {
1009 fsc = nla_data(tb[TCA_HFSC_FSC]);
1010 if (fsc->m1 == 0 && fsc->m2 == 0)
1011 fsc = NULL;
1012 }
1013
1014 if (tb[TCA_HFSC_USC]) {
1015 usc = nla_data(tb[TCA_HFSC_USC]);
1016 if (usc->m1 == 0 && usc->m2 == 0)
1017 usc = NULL;
1018 }
1019
1020 if (cl != NULL) {
1021 if (parentid) {
1022 if (cl->cl_parent &&
1023 cl->cl_parent->cl_common.classid != parentid)
1024 return -EINVAL;
1025 if (cl->cl_parent == NULL && parentid != TC_H_ROOT)
1026 return -EINVAL;
1027 }
1028 cur_time = psched_get_time();
1029
1030 sch_tree_lock(sch);
1031 if (rsc != NULL)
1032 hfsc_change_rsc(cl, rsc, cur_time);
1033 if (fsc != NULL)
1034 hfsc_change_fsc(cl, fsc);
1035 if (usc != NULL)
1036 hfsc_change_usc(cl, usc, cur_time);
1037
1038 if (cl->qdisc->q.qlen != 0) {
1039 if (cl->cl_flags & HFSC_RSC)
1040 update_ed(cl, qdisc_peek_len(cl->qdisc));
1041 if (cl->cl_flags & HFSC_FSC)
1042 update_vf(cl, 0, cur_time);
1043 }
1044 sch_tree_unlock(sch);
1045
1046 if (tca[TCA_RATE])
1047 gen_replace_estimator(&cl->bstats, &cl->rate_est,
1048 qdisc_root_lock(sch),
1049 tca[TCA_RATE]);
1050 return 0;
1051 }
1052
1053 if (parentid == TC_H_ROOT)
1054 return -EEXIST;
1055
1056 parent = &q->root;
1057 if (parentid) {
1058 parent = hfsc_find_class(parentid, sch);
1059 if (parent == NULL)
1060 return -ENOENT;
1061 }
1062
1063 if (classid == 0 || TC_H_MAJ(classid ^ sch->handle) != 0)
1064 return -EINVAL;
1065 if (hfsc_find_class(classid, sch))
1066 return -EEXIST;
1067
1068 if (rsc == NULL && fsc == NULL)
1069 return -EINVAL;
1070
1071 cl = kzalloc(sizeof(struct hfsc_class), GFP_KERNEL);
1072 if (cl == NULL)
1073 return -ENOBUFS;
1074
1075 if (rsc != NULL)
1076 hfsc_change_rsc(cl, rsc, 0);
1077 if (fsc != NULL)
1078 hfsc_change_fsc(cl, fsc);
1079 if (usc != NULL)
1080 hfsc_change_usc(cl, usc, 0);
1081
1082 cl->cl_common.classid = classid;
1083 cl->refcnt = 1;
1084 cl->sched = q;
1085 cl->cl_parent = parent;
1086 cl->qdisc = qdisc_create_dflt(qdisc_dev(sch), sch->dev_queue,
1087 &pfifo_qdisc_ops, classid);
1088 if (cl->qdisc == NULL)
1089 cl->qdisc = &noop_qdisc;
1090 INIT_LIST_HEAD(&cl->children);
1091 cl->vt_tree = RB_ROOT;
1092 cl->cf_tree = RB_ROOT;
1093
1094 sch_tree_lock(sch);
1095 qdisc_class_hash_insert(&q->clhash, &cl->cl_common);
1096 list_add_tail(&cl->siblings, &parent->children);
1097 if (parent->level == 0)
1098 hfsc_purge_queue(sch, parent);
1099 hfsc_adjust_levels(parent);
1100 cl->cl_pcvtoff = parent->cl_cvtoff;
1101 sch_tree_unlock(sch);
1102
1103 qdisc_class_hash_grow(sch, &q->clhash);
1104
1105 if (tca[TCA_RATE])
1106 gen_new_estimator(&cl->bstats, &cl->rate_est,
1107 qdisc_root_lock(sch), tca[TCA_RATE]);
1108 *arg = (unsigned long)cl;
1109 return 0;
1110 }
1111
1112 static void
1113 hfsc_destroy_class(struct Qdisc *sch, struct hfsc_class *cl)
1114 {
1115 struct hfsc_sched *q = qdisc_priv(sch);
1116
1117 tcf_destroy_chain(&cl->filter_list);
1118 qdisc_destroy(cl->qdisc);
1119 gen_kill_estimator(&cl->bstats, &cl->rate_est);
1120 if (cl != &q->root)
1121 kfree(cl);
1122 }
1123
1124 static int
1125 hfsc_delete_class(struct Qdisc *sch, unsigned long arg)
1126 {
1127 struct hfsc_sched *q = qdisc_priv(sch);
1128 struct hfsc_class *cl = (struct hfsc_class *)arg;
1129
1130 if (cl->level > 0 || cl->filter_cnt > 0 || cl == &q->root)
1131 return -EBUSY;
1132
1133 sch_tree_lock(sch);
1134
1135 list_del(&cl->siblings);
1136 hfsc_adjust_levels(cl->cl_parent);
1137
1138 hfsc_purge_queue(sch, cl);
1139 qdisc_class_hash_remove(&q->clhash, &cl->cl_common);
1140
1141 if (--cl->refcnt == 0)
1142 hfsc_destroy_class(sch, cl);
1143
1144 sch_tree_unlock(sch);
1145 return 0;
1146 }
1147
1148 static struct hfsc_class *
1149 hfsc_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
1150 {
1151 struct hfsc_sched *q = qdisc_priv(sch);
1152 struct hfsc_class *cl;
1153 struct tcf_result res;
1154 struct tcf_proto *tcf;
1155 int result;
1156
1157 if (TC_H_MAJ(skb->priority ^ sch->handle) == 0 &&
1158 (cl = hfsc_find_class(skb->priority, sch)) != NULL)
1159 if (cl->level == 0)
1160 return cl;
1161
1162 *qerr = NET_XMIT_BYPASS;
1163 tcf = q->root.filter_list;
1164 while (tcf && (result = tc_classify(skb, tcf, &res)) >= 0) {
1165 #ifdef CONFIG_NET_CLS_ACT
1166 switch (result) {
1167 case TC_ACT_QUEUED:
1168 case TC_ACT_STOLEN:
1169 *qerr = NET_XMIT_SUCCESS;
1170 case TC_ACT_SHOT:
1171 return NULL;
1172 }
1173 #endif
1174 if ((cl = (struct hfsc_class *)res.class) == NULL) {
1175 if ((cl = hfsc_find_class(res.classid, sch)) == NULL)
1176 break; /* filter selected invalid classid */
1177 }
1178
1179 if (cl->level == 0)
1180 return cl; /* hit leaf class */
1181
1182 /* apply inner filter chain */
1183 tcf = cl->filter_list;
1184 }
1185
1186 /* classification failed, try default class */
1187 cl = hfsc_find_class(TC_H_MAKE(TC_H_MAJ(sch->handle), q->defcls), sch);
1188 if (cl == NULL || cl->level > 0)
1189 return NULL;
1190
1191 return cl;
1192 }
1193
1194 static int
1195 hfsc_graft_class(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
1196 struct Qdisc **old)
1197 {
1198 struct hfsc_class *cl = (struct hfsc_class *)arg;
1199
1200 if (cl == NULL)
1201 return -ENOENT;
1202 if (cl->level > 0)
1203 return -EINVAL;
1204 if (new == NULL) {
1205 new = qdisc_create_dflt(qdisc_dev(sch), sch->dev_queue,
1206 &pfifo_qdisc_ops,
1207 cl->cl_common.classid);
1208 if (new == NULL)
1209 new = &noop_qdisc;
1210 }
1211
1212 sch_tree_lock(sch);
1213 hfsc_purge_queue(sch, cl);
1214 *old = xchg(&cl->qdisc, new);
1215 sch_tree_unlock(sch);
1216 return 0;
1217 }
1218
1219 static struct Qdisc *
1220 hfsc_class_leaf(struct Qdisc *sch, unsigned long arg)
1221 {
1222 struct hfsc_class *cl = (struct hfsc_class *)arg;
1223
1224 if (cl != NULL && cl->level == 0)
1225 return cl->qdisc;
1226
1227 return NULL;
1228 }
1229
1230 static void
1231 hfsc_qlen_notify(struct Qdisc *sch, unsigned long arg)
1232 {
1233 struct hfsc_class *cl = (struct hfsc_class *)arg;
1234
1235 if (cl->qdisc->q.qlen == 0) {
1236 update_vf(cl, 0, 0);
1237 set_passive(cl);
1238 }
1239 }
1240
1241 static unsigned long
1242 hfsc_get_class(struct Qdisc *sch, u32 classid)
1243 {
1244 struct hfsc_class *cl = hfsc_find_class(classid, sch);
1245
1246 if (cl != NULL)
1247 cl->refcnt++;
1248
1249 return (unsigned long)cl;
1250 }
1251
1252 static void
1253 hfsc_put_class(struct Qdisc *sch, unsigned long arg)
1254 {
1255 struct hfsc_class *cl = (struct hfsc_class *)arg;
1256
1257 if (--cl->refcnt == 0)
1258 hfsc_destroy_class(sch, cl);
1259 }
1260
1261 static unsigned long
1262 hfsc_bind_tcf(struct Qdisc *sch, unsigned long parent, u32 classid)
1263 {
1264 struct hfsc_class *p = (struct hfsc_class *)parent;
1265 struct hfsc_class *cl = hfsc_find_class(classid, sch);
1266
1267 if (cl != NULL) {
1268 if (p != NULL && p->level <= cl->level)
1269 return 0;
1270 cl->filter_cnt++;
1271 }
1272
1273 return (unsigned long)cl;
1274 }
1275
1276 static void
1277 hfsc_unbind_tcf(struct Qdisc *sch, unsigned long arg)
1278 {
1279 struct hfsc_class *cl = (struct hfsc_class *)arg;
1280
1281 cl->filter_cnt--;
1282 }
1283
1284 static struct tcf_proto **
1285 hfsc_tcf_chain(struct Qdisc *sch, unsigned long arg)
1286 {
1287 struct hfsc_sched *q = qdisc_priv(sch);
1288 struct hfsc_class *cl = (struct hfsc_class *)arg;
1289
1290 if (cl == NULL)
1291 cl = &q->root;
1292
1293 return &cl->filter_list;
1294 }
1295
1296 static int
1297 hfsc_dump_sc(struct sk_buff *skb, int attr, struct internal_sc *sc)
1298 {
1299 struct tc_service_curve tsc;
1300
1301 tsc.m1 = sm2m(sc->sm1);
1302 tsc.d = dx2d(sc->dx);
1303 tsc.m2 = sm2m(sc->sm2);
1304 NLA_PUT(skb, attr, sizeof(tsc), &tsc);
1305
1306 return skb->len;
1307
1308 nla_put_failure:
1309 return -1;
1310 }
1311
1312 static inline int
1313 hfsc_dump_curves(struct sk_buff *skb, struct hfsc_class *cl)
1314 {
1315 if ((cl->cl_flags & HFSC_RSC) &&
1316 (hfsc_dump_sc(skb, TCA_HFSC_RSC, &cl->cl_rsc) < 0))
1317 goto nla_put_failure;
1318
1319 if ((cl->cl_flags & HFSC_FSC) &&
1320 (hfsc_dump_sc(skb, TCA_HFSC_FSC, &cl->cl_fsc) < 0))
1321 goto nla_put_failure;
1322
1323 if ((cl->cl_flags & HFSC_USC) &&
1324 (hfsc_dump_sc(skb, TCA_HFSC_USC, &cl->cl_usc) < 0))
1325 goto nla_put_failure;
1326
1327 return skb->len;
1328
1329 nla_put_failure:
1330 return -1;
1331 }
1332
1333 static int
1334 hfsc_dump_class(struct Qdisc *sch, unsigned long arg, struct sk_buff *skb,
1335 struct tcmsg *tcm)
1336 {
1337 struct hfsc_class *cl = (struct hfsc_class *)arg;
1338 struct nlattr *nest;
1339
1340 tcm->tcm_parent = cl->cl_parent ? cl->cl_parent->cl_common.classid :
1341 TC_H_ROOT;
1342 tcm->tcm_handle = cl->cl_common.classid;
1343 if (cl->level == 0)
1344 tcm->tcm_info = cl->qdisc->handle;
1345
1346 nest = nla_nest_start(skb, TCA_OPTIONS);
1347 if (nest == NULL)
1348 goto nla_put_failure;
1349 if (hfsc_dump_curves(skb, cl) < 0)
1350 goto nla_put_failure;
1351 nla_nest_end(skb, nest);
1352 return skb->len;
1353
1354 nla_put_failure:
1355 nla_nest_cancel(skb, nest);
1356 return -EMSGSIZE;
1357 }
1358
1359 static int
1360 hfsc_dump_class_stats(struct Qdisc *sch, unsigned long arg,
1361 struct gnet_dump *d)
1362 {
1363 struct hfsc_class *cl = (struct hfsc_class *)arg;
1364 struct tc_hfsc_stats xstats;
1365
1366 cl->qstats.qlen = cl->qdisc->q.qlen;
1367 xstats.level = cl->level;
1368 xstats.period = cl->cl_vtperiod;
1369 xstats.work = cl->cl_total;
1370 xstats.rtwork = cl->cl_cumul;
1371
1372 if (gnet_stats_copy_basic(d, &cl->bstats) < 0 ||
1373 gnet_stats_copy_rate_est(d, &cl->rate_est) < 0 ||
1374 gnet_stats_copy_queue(d, &cl->qstats) < 0)
1375 return -1;
1376
1377 return gnet_stats_copy_app(d, &xstats, sizeof(xstats));
1378 }
1379
1380
1381
1382 static void
1383 hfsc_walk(struct Qdisc *sch, struct qdisc_walker *arg)
1384 {
1385 struct hfsc_sched *q = qdisc_priv(sch);
1386 struct hlist_node *n;
1387 struct hfsc_class *cl;
1388 unsigned int i;
1389
1390 if (arg->stop)
1391 return;
1392
1393 for (i = 0; i < q->clhash.hashsize; i++) {
1394 hlist_for_each_entry(cl, n, &q->clhash.hash[i],
1395 cl_common.hnode) {
1396 if (arg->count < arg->skip) {
1397 arg->count++;
1398 continue;
1399 }
1400 if (arg->fn(sch, (unsigned long)cl, arg) < 0) {
1401 arg->stop = 1;
1402 return;
1403 }
1404 arg->count++;
1405 }
1406 }
1407 }
1408
1409 static void
1410 hfsc_schedule_watchdog(struct Qdisc *sch)
1411 {
1412 struct hfsc_sched *q = qdisc_priv(sch);
1413 struct hfsc_class *cl;
1414 u64 next_time = 0;
1415
1416 if ((cl = eltree_get_minel(q)) != NULL)
1417 next_time = cl->cl_e;
1418 if (q->root.cl_cfmin != 0) {
1419 if (next_time == 0 || next_time > q->root.cl_cfmin)
1420 next_time = q->root.cl_cfmin;
1421 }
1422 WARN_ON(next_time == 0);
1423 qdisc_watchdog_schedule(&q->watchdog, next_time);
1424 }
1425
1426 static int
1427 hfsc_init_qdisc(struct Qdisc *sch, struct nlattr *opt)
1428 {
1429 struct hfsc_sched *q = qdisc_priv(sch);
1430 struct tc_hfsc_qopt *qopt;
1431 int err;
1432
1433 if (opt == NULL || nla_len(opt) < sizeof(*qopt))
1434 return -EINVAL;
1435 qopt = nla_data(opt);
1436
1437 q->defcls = qopt->defcls;
1438 err = qdisc_class_hash_init(&q->clhash);
1439 if (err < 0)
1440 return err;
1441 q->eligible = RB_ROOT;
1442 INIT_LIST_HEAD(&q->droplist);
1443 skb_queue_head_init(&q->requeue);
1444
1445 q->root.cl_common.classid = sch->handle;
1446 q->root.refcnt = 1;
1447 q->root.sched = q;
1448 q->root.qdisc = qdisc_create_dflt(qdisc_dev(sch), sch->dev_queue,
1449 &pfifo_qdisc_ops,
1450 sch->handle);
1451 if (q->root.qdisc == NULL)
1452 q->root.qdisc = &noop_qdisc;
1453 INIT_LIST_HEAD(&q->root.children);
1454 q->root.vt_tree = RB_ROOT;
1455 q->root.cf_tree = RB_ROOT;
1456
1457 qdisc_class_hash_insert(&q->clhash, &q->root.cl_common);
1458 qdisc_class_hash_grow(sch, &q->clhash);
1459
1460 qdisc_watchdog_init(&q->watchdog, sch);
1461
1462 return 0;
1463 }
1464
1465 static int
1466 hfsc_change_qdisc(struct Qdisc *sch, struct nlattr *opt)
1467 {
1468 struct hfsc_sched *q = qdisc_priv(sch);
1469 struct tc_hfsc_qopt *qopt;
1470
1471 if (opt == NULL || nla_len(opt) < sizeof(*qopt))
1472 return -EINVAL;
1473 qopt = nla_data(opt);
1474
1475 sch_tree_lock(sch);
1476 q->defcls = qopt->defcls;
1477 sch_tree_unlock(sch);
1478
1479 return 0;
1480 }
1481
1482 static void
1483 hfsc_reset_class(struct hfsc_class *cl)
1484 {
1485 cl->cl_total = 0;
1486 cl->cl_cumul = 0;
1487 cl->cl_d = 0;
1488 cl->cl_e = 0;
1489 cl->cl_vt = 0;
1490 cl->cl_vtadj = 0;
1491 cl->cl_vtoff = 0;
1492 cl->cl_cvtmin = 0;
1493 cl->cl_cvtmax = 0;
1494 cl->cl_cvtoff = 0;
1495 cl->cl_pcvtoff = 0;
1496 cl->cl_vtperiod = 0;
1497 cl->cl_parentperiod = 0;
1498 cl->cl_f = 0;
1499 cl->cl_myf = 0;
1500 cl->cl_myfadj = 0;
1501 cl->cl_cfmin = 0;
1502 cl->cl_nactive = 0;
1503
1504 cl->vt_tree = RB_ROOT;
1505 cl->cf_tree = RB_ROOT;
1506 qdisc_reset(cl->qdisc);
1507
1508 if (cl->cl_flags & HFSC_RSC)
1509 rtsc_init(&cl->cl_deadline, &cl->cl_rsc, 0, 0);
1510 if (cl->cl_flags & HFSC_FSC)
1511 rtsc_init(&cl->cl_virtual, &cl->cl_fsc, 0, 0);
1512 if (cl->cl_flags & HFSC_USC)
1513 rtsc_init(&cl->cl_ulimit, &cl->cl_usc, 0, 0);
1514 }
1515
1516 static void
1517 hfsc_reset_qdisc(struct Qdisc *sch)
1518 {
1519 struct hfsc_sched *q = qdisc_priv(sch);
1520 struct hfsc_class *cl;
1521 struct hlist_node *n;
1522 unsigned int i;
1523
1524 for (i = 0; i < q->clhash.hashsize; i++) {
1525 hlist_for_each_entry(cl, n, &q->clhash.hash[i], cl_common.hnode)
1526 hfsc_reset_class(cl);
1527 }
1528 __skb_queue_purge(&q->requeue);
1529 q->eligible = RB_ROOT;
1530 INIT_LIST_HEAD(&q->droplist);
1531 qdisc_watchdog_cancel(&q->watchdog);
1532 sch->q.qlen = 0;
1533 }
1534
1535 static void
1536 hfsc_destroy_qdisc(struct Qdisc *sch)
1537 {
1538 struct hfsc_sched *q = qdisc_priv(sch);
1539 struct hlist_node *n, *next;
1540 struct hfsc_class *cl;
1541 unsigned int i;
1542
1543 for (i = 0; i < q->clhash.hashsize; i++) {
1544 hlist_for_each_entry(cl, n, &q->clhash.hash[i], cl_common.hnode)
1545 tcf_destroy_chain(&cl->filter_list);
1546 }
1547 for (i = 0; i < q->clhash.hashsize; i++) {
1548 hlist_for_each_entry_safe(cl, n, next, &q->clhash.hash[i],
1549 cl_common.hnode)
1550 hfsc_destroy_class(sch, cl);
1551 }
1552 qdisc_class_hash_destroy(&q->clhash);
1553 __skb_queue_purge(&q->requeue);
1554 qdisc_watchdog_cancel(&q->watchdog);
1555 }
1556
1557 static int
1558 hfsc_dump_qdisc(struct Qdisc *sch, struct sk_buff *skb)
1559 {
1560 struct hfsc_sched *q = qdisc_priv(sch);
1561 unsigned char *b = skb_tail_pointer(skb);
1562 struct tc_hfsc_qopt qopt;
1563
1564 qopt.defcls = q->defcls;
1565 NLA_PUT(skb, TCA_OPTIONS, sizeof(qopt), &qopt);
1566 return skb->len;
1567
1568 nla_put_failure:
1569 nlmsg_trim(skb, b);
1570 return -1;
1571 }
1572
1573 static int
1574 hfsc_enqueue(struct sk_buff *skb, struct Qdisc *sch)
1575 {
1576 struct hfsc_class *cl;
1577 int err;
1578
1579 cl = hfsc_classify(skb, sch, &err);
1580 if (cl == NULL) {
1581 if (err == NET_XMIT_BYPASS)
1582 sch->qstats.drops++;
1583 kfree_skb(skb);
1584 return err;
1585 }
1586
1587 err = qdisc_enqueue(skb, cl->qdisc);
1588 if (unlikely(err != NET_XMIT_SUCCESS)) {
1589 cl->qstats.drops++;
1590 sch->qstats.drops++;
1591 return err;
1592 }
1593
1594 if (cl->qdisc->q.qlen == 1)
1595 set_active(cl, qdisc_pkt_len(skb));
1596
1597 cl->bstats.packets++;
1598 cl->bstats.bytes += qdisc_pkt_len(skb);
1599 sch->bstats.packets++;
1600 sch->bstats.bytes += qdisc_pkt_len(skb);
1601 sch->q.qlen++;
1602
1603 return NET_XMIT_SUCCESS;
1604 }
1605
1606 static struct sk_buff *
1607 hfsc_dequeue(struct Qdisc *sch)
1608 {
1609 struct hfsc_sched *q = qdisc_priv(sch);
1610 struct hfsc_class *cl;
1611 struct sk_buff *skb;
1612 u64 cur_time;
1613 unsigned int next_len;
1614 int realtime = 0;
1615
1616 if (sch->q.qlen == 0)
1617 return NULL;
1618 if ((skb = __skb_dequeue(&q->requeue)))
1619 goto out;
1620
1621 cur_time = psched_get_time();
1622
1623 /*
1624 * if there are eligible classes, use real-time criteria.
1625 * find the class with the minimum deadline among
1626 * the eligible classes.
1627 */
1628 if ((cl = eltree_get_mindl(q, cur_time)) != NULL) {
1629 realtime = 1;
1630 } else {
1631 /*
1632 * use link-sharing criteria
1633 * get the class with the minimum vt in the hierarchy
1634 */
1635 cl = vttree_get_minvt(&q->root, cur_time);
1636 if (cl == NULL) {
1637 sch->qstats.overlimits++;
1638 hfsc_schedule_watchdog(sch);
1639 return NULL;
1640 }
1641 }
1642
1643 skb = cl->qdisc->dequeue(cl->qdisc);
1644 if (skb == NULL) {
1645 if (net_ratelimit())
1646 printk("HFSC: Non-work-conserving qdisc ?\n");
1647 return NULL;
1648 }
1649
1650 update_vf(cl, qdisc_pkt_len(skb), cur_time);
1651 if (realtime)
1652 cl->cl_cumul += qdisc_pkt_len(skb);
1653
1654 if (cl->qdisc->q.qlen != 0) {
1655 if (cl->cl_flags & HFSC_RSC) {
1656 /* update ed */
1657 next_len = qdisc_peek_len(cl->qdisc);
1658 if (realtime)
1659 update_ed(cl, next_len);
1660 else
1661 update_d(cl, next_len);
1662 }
1663 } else {
1664 /* the class becomes passive */
1665 set_passive(cl);
1666 }
1667
1668 out:
1669 sch->flags &= ~TCQ_F_THROTTLED;
1670 sch->q.qlen--;
1671
1672 return skb;
1673 }
1674
1675 static int
1676 hfsc_requeue(struct sk_buff *skb, struct Qdisc *sch)
1677 {
1678 struct hfsc_sched *q = qdisc_priv(sch);
1679
1680 __skb_queue_head(&q->requeue, skb);
1681 sch->q.qlen++;
1682 sch->qstats.requeues++;
1683 return NET_XMIT_SUCCESS;
1684 }
1685
1686 static unsigned int
1687 hfsc_drop(struct Qdisc *sch)
1688 {
1689 struct hfsc_sched *q = qdisc_priv(sch);
1690 struct hfsc_class *cl;
1691 unsigned int len;
1692
1693 list_for_each_entry(cl, &q->droplist, dlist) {
1694 if (cl->qdisc->ops->drop != NULL &&
1695 (len = cl->qdisc->ops->drop(cl->qdisc)) > 0) {
1696 if (cl->qdisc->q.qlen == 0) {
1697 update_vf(cl, 0, 0);
1698 set_passive(cl);
1699 } else {
1700 list_move_tail(&cl->dlist, &q->droplist);
1701 }
1702 cl->qstats.drops++;
1703 sch->qstats.drops++;
1704 sch->q.qlen--;
1705 return len;
1706 }
1707 }
1708 return 0;
1709 }
1710
1711 static const struct Qdisc_class_ops hfsc_class_ops = {
1712 .change = hfsc_change_class,
1713 .delete = hfsc_delete_class,
1714 .graft = hfsc_graft_class,
1715 .leaf = hfsc_class_leaf,
1716 .qlen_notify = hfsc_qlen_notify,
1717 .get = hfsc_get_class,
1718 .put = hfsc_put_class,
1719 .bind_tcf = hfsc_bind_tcf,
1720 .unbind_tcf = hfsc_unbind_tcf,
1721 .tcf_chain = hfsc_tcf_chain,
1722 .dump = hfsc_dump_class,
1723 .dump_stats = hfsc_dump_class_stats,
1724 .walk = hfsc_walk
1725 };
1726
1727 static struct Qdisc_ops hfsc_qdisc_ops __read_mostly = {
1728 .id = "hfsc",
1729 .init = hfsc_init_qdisc,
1730 .change = hfsc_change_qdisc,
1731 .reset = hfsc_reset_qdisc,
1732 .destroy = hfsc_destroy_qdisc,
1733 .dump = hfsc_dump_qdisc,
1734 .enqueue = hfsc_enqueue,
1735 .dequeue = hfsc_dequeue,
1736 .requeue = hfsc_requeue,
1737 .drop = hfsc_drop,
1738 .cl_ops = &hfsc_class_ops,
1739 .priv_size = sizeof(struct hfsc_sched),
1740 .owner = THIS_MODULE
1741 };
1742
1743 static int __init
1744 hfsc_init(void)
1745 {
1746 return register_qdisc(&hfsc_qdisc_ops);
1747 }
1748
1749 static void __exit
1750 hfsc_cleanup(void)
1751 {
1752 unregister_qdisc(&hfsc_qdisc_ops);
1753 }
1754
1755 MODULE_LICENSE("GPL");
1756 module_init(hfsc_init);
1757 module_exit(hfsc_cleanup);
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