Merge branch 'master' into upstream
[linux-2.6] / net / sched / sch_hfsc.c
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/config.h>
54 #include <linux/module.h>
55 #include <linux/types.h>
56 #include <linux/errno.h>
57 #include <linux/jiffies.h>
58 #include <linux/compiler.h>
59 #include <linux/spinlock.h>
60 #include <linux/skbuff.h>
61 #include <linux/string.h>
62 #include <linux/slab.h>
63 #include <linux/timer.h>
64 #include <linux/list.h>
65 #include <linux/rbtree.h>
66 #include <linux/init.h>
67 #include <linux/netdevice.h>
68 #include <linux/rtnetlink.h>
69 #include <linux/pkt_sched.h>
70 #include <net/pkt_sched.h>
71 #include <net/pkt_cls.h>
72 #include <asm/system.h>
73 #include <asm/div64.h>
74
75 #define HFSC_DEBUG 1
76
77 /*
78  * kernel internal service curve representation:
79  *   coordinates are given by 64 bit unsigned integers.
80  *   x-axis: unit is clock count.
81  *   y-axis: unit is byte.
82  *
83  *   The service curve parameters are converted to the internal
84  *   representation. The slope values are scaled to avoid overflow.
85  *   the inverse slope values as well as the y-projection of the 1st
86  *   segment are kept in order to to avoid 64-bit divide operations
87  *   that are expensive on 32-bit architectures.
88  */
89
90 struct internal_sc
91 {
92         u64     sm1;    /* scaled slope of the 1st segment */
93         u64     ism1;   /* scaled inverse-slope of the 1st segment */
94         u64     dx;     /* the x-projection of the 1st segment */
95         u64     dy;     /* the y-projection of the 1st segment */
96         u64     sm2;    /* scaled slope of the 2nd segment */
97         u64     ism2;   /* scaled inverse-slope of the 2nd segment */
98 };
99
100 /* runtime service curve */
101 struct runtime_sc
102 {
103         u64     x;      /* current starting position on x-axis */
104         u64     y;      /* current starting position on y-axis */
105         u64     sm1;    /* scaled slope of the 1st segment */
106         u64     ism1;   /* scaled inverse-slope of the 1st segment */
107         u64     dx;     /* the x-projection of the 1st segment */
108         u64     dy;     /* the y-projection of the 1st segment */
109         u64     sm2;    /* scaled slope of the 2nd segment */
110         u64     ism2;   /* scaled inverse-slope of the 2nd segment */
111 };
112
113 enum hfsc_class_flags
114 {
115         HFSC_RSC = 0x1,
116         HFSC_FSC = 0x2,
117         HFSC_USC = 0x4
118 };
119
120 struct hfsc_class
121 {
122         u32             classid;        /* class id */
123         unsigned int    refcnt;         /* usage count */
124
125         struct gnet_stats_basic bstats;
126         struct gnet_stats_queue qstats;
127         struct gnet_stats_rate_est rate_est;
128         spinlock_t      *stats_lock;
129         unsigned int    level;          /* class level in hierarchy */
130         struct tcf_proto *filter_list;  /* filter list */
131         unsigned int    filter_cnt;     /* filter count */
132
133         struct hfsc_sched *sched;       /* scheduler data */
134         struct hfsc_class *cl_parent;   /* parent class */
135         struct list_head siblings;      /* sibling classes */
136         struct list_head children;      /* child classes */
137         struct Qdisc    *qdisc;         /* leaf qdisc */
138
139         struct rb_node el_node;         /* qdisc's eligible tree member */
140         struct rb_root vt_tree;         /* active children sorted by cl_vt */
141         struct rb_node vt_node;         /* parent's vt_tree member */
142         struct rb_root cf_tree;         /* active children sorted by cl_f */
143         struct rb_node cf_node;         /* parent's cf_heap member */
144         struct list_head hlist;         /* hash list member */
145         struct list_head dlist;         /* drop list member */
146
147         u64     cl_total;               /* total work in bytes */
148         u64     cl_cumul;               /* cumulative work in bytes done by
149                                            real-time criteria */
150
151         u64     cl_d;                   /* deadline*/
152         u64     cl_e;                   /* eligible time */
153         u64     cl_vt;                  /* virtual time */
154         u64     cl_f;                   /* time when this class will fit for
155                                            link-sharing, max(myf, cfmin) */
156         u64     cl_myf;                 /* my fit-time (calculated from this
157                                            class's own upperlimit curve) */
158         u64     cl_myfadj;              /* my fit-time adjustment (to cancel
159                                            history dependence) */
160         u64     cl_cfmin;               /* earliest children's fit-time (used
161                                            with cl_myf to obtain cl_f) */
162         u64     cl_cvtmin;              /* minimal virtual time among the
163                                            children fit for link-sharing
164                                            (monotonic within a period) */
165         u64     cl_vtadj;               /* intra-period cumulative vt
166                                            adjustment */
167         u64     cl_vtoff;               /* inter-period cumulative vt offset */
168         u64     cl_cvtmax;              /* max child's vt in the last period */
169         u64     cl_cvtoff;              /* cumulative cvtmax of all periods */
170         u64     cl_pcvtoff;             /* parent's cvtoff at initalization
171                                            time */
172
173         struct internal_sc cl_rsc;      /* internal real-time service curve */
174         struct internal_sc cl_fsc;      /* internal fair service curve */
175         struct internal_sc cl_usc;      /* internal upperlimit service curve */
176         struct runtime_sc cl_deadline;  /* deadline curve */
177         struct runtime_sc cl_eligible;  /* eligible curve */
178         struct runtime_sc cl_virtual;   /* virtual curve */
179         struct runtime_sc cl_ulimit;    /* upperlimit curve */
180
181         unsigned long   cl_flags;       /* which curves are valid */
182         unsigned long   cl_vtperiod;    /* vt period sequence number */
183         unsigned long   cl_parentperiod;/* parent's vt period sequence number*/
184         unsigned long   cl_nactive;     /* number of active children */
185 };
186
187 #define HFSC_HSIZE      16
188
189 struct hfsc_sched
190 {
191         u16     defcls;                         /* default class id */
192         struct hfsc_class root;                 /* root class */
193         struct list_head clhash[HFSC_HSIZE];    /* class hash */
194         struct rb_root eligible;                /* eligible tree */
195         struct list_head droplist;              /* active leaf class list (for
196                                                    dropping) */
197         struct sk_buff_head requeue;            /* requeued packet */
198         struct timer_list wd_timer;             /* watchdog timer */
199 };
200
201 /*
202  * macros
203  */
204 #ifdef CONFIG_NET_SCH_CLK_GETTIMEOFDAY
205 #include <linux/time.h>
206 #undef PSCHED_GET_TIME
207 #define PSCHED_GET_TIME(stamp)                                          \
208 do {                                                                    \
209         struct timeval tv;                                              \
210         do_gettimeofday(&tv);                                           \
211         (stamp) = 1ULL * USEC_PER_SEC * tv.tv_sec + tv.tv_usec;         \
212 } while (0)
213 #endif
214
215 #if HFSC_DEBUG
216 #define ASSERT(cond)                                                    \
217 do {                                                                    \
218         if (unlikely(!(cond)))                                          \
219                 printk("assertion %s failed at %s:%i (%s)\n",           \
220                        #cond, __FILE__, __LINE__, __FUNCTION__);        \
221 } while (0)
222 #else
223 #define ASSERT(cond)
224 #endif /* HFSC_DEBUG */
225
226 #define HT_INFINITY     0xffffffffffffffffULL   /* infinite time value */
227
228
229 /*
230  * eligible tree holds backlogged classes being sorted by their eligible times.
231  * there is one eligible tree per hfsc instance.
232  */
233
234 static void
235 eltree_insert(struct hfsc_class *cl)
236 {
237         struct rb_node **p = &cl->sched->eligible.rb_node;
238         struct rb_node *parent = NULL;
239         struct hfsc_class *cl1;
240
241         while (*p != NULL) {
242                 parent = *p;
243                 cl1 = rb_entry(parent, struct hfsc_class, el_node);
244                 if (cl->cl_e >= cl1->cl_e)
245                         p = &parent->rb_right;
246                 else
247                         p = &parent->rb_left;
248         }
249         rb_link_node(&cl->el_node, parent, p);
250         rb_insert_color(&cl->el_node, &cl->sched->eligible);
251 }
252
253 static inline void
254 eltree_remove(struct hfsc_class *cl)
255 {
256         rb_erase(&cl->el_node, &cl->sched->eligible);
257 }
258
259 static inline void
260 eltree_update(struct hfsc_class *cl)
261 {
262         eltree_remove(cl);
263         eltree_insert(cl);
264 }
265
266 /* find the class with the minimum deadline among the eligible classes */
267 static inline struct hfsc_class *
268 eltree_get_mindl(struct hfsc_sched *q, u64 cur_time)
269 {
270         struct hfsc_class *p, *cl = NULL;
271         struct rb_node *n;
272
273         for (n = rb_first(&q->eligible); n != NULL; n = rb_next(n)) {
274                 p = rb_entry(n, struct hfsc_class, el_node);
275                 if (p->cl_e > cur_time)
276                         break;
277                 if (cl == NULL || p->cl_d < cl->cl_d)
278                         cl = p;
279         }
280         return cl;
281 }
282
283 /* find the class with minimum eligible time among the eligible classes */
284 static inline struct hfsc_class *
285 eltree_get_minel(struct hfsc_sched *q)
286 {
287         struct rb_node *n;
288         
289         n = rb_first(&q->eligible);
290         if (n == NULL)
291                 return NULL;
292         return rb_entry(n, struct hfsc_class, el_node);
293 }
294
295 /*
296  * vttree holds holds backlogged child classes being sorted by their virtual
297  * time. each intermediate class has one vttree.
298  */
299 static void
300 vttree_insert(struct hfsc_class *cl)
301 {
302         struct rb_node **p = &cl->cl_parent->vt_tree.rb_node;
303         struct rb_node *parent = NULL;
304         struct hfsc_class *cl1;
305
306         while (*p != NULL) {
307                 parent = *p;
308                 cl1 = rb_entry(parent, struct hfsc_class, vt_node);
309                 if (cl->cl_vt >= cl1->cl_vt)
310                         p = &parent->rb_right;
311                 else
312                         p = &parent->rb_left;
313         }
314         rb_link_node(&cl->vt_node, parent, p);
315         rb_insert_color(&cl->vt_node, &cl->cl_parent->vt_tree);
316 }
317
318 static inline void
319 vttree_remove(struct hfsc_class *cl)
320 {
321         rb_erase(&cl->vt_node, &cl->cl_parent->vt_tree);
322 }
323
324 static inline void
325 vttree_update(struct hfsc_class *cl)
326 {
327         vttree_remove(cl);
328         vttree_insert(cl);
329 }
330
331 static inline struct hfsc_class *
332 vttree_firstfit(struct hfsc_class *cl, u64 cur_time)
333 {
334         struct hfsc_class *p;
335         struct rb_node *n;
336
337         for (n = rb_first(&cl->vt_tree); n != NULL; n = rb_next(n)) {
338                 p = rb_entry(n, struct hfsc_class, vt_node);
339                 if (p->cl_f <= cur_time)
340                         return p;
341         }
342         return NULL;
343 }
344
345 /*
346  * get the leaf class with the minimum vt in the hierarchy
347  */
348 static struct hfsc_class *
349 vttree_get_minvt(struct hfsc_class *cl, u64 cur_time)
350 {
351         /* if root-class's cfmin is bigger than cur_time nothing to do */
352         if (cl->cl_cfmin > cur_time)
353                 return NULL;
354
355         while (cl->level > 0) {
356                 cl = vttree_firstfit(cl, cur_time);
357                 if (cl == NULL)
358                         return NULL;
359                 /*
360                  * update parent's cl_cvtmin.
361                  */
362                 if (cl->cl_parent->cl_cvtmin < cl->cl_vt)
363                         cl->cl_parent->cl_cvtmin = cl->cl_vt;
364         }
365         return cl;
366 }
367
368 static void
369 cftree_insert(struct hfsc_class *cl)
370 {
371         struct rb_node **p = &cl->cl_parent->cf_tree.rb_node;
372         struct rb_node *parent = NULL;
373         struct hfsc_class *cl1;
374
375         while (*p != NULL) {
376                 parent = *p;
377                 cl1 = rb_entry(parent, struct hfsc_class, cf_node);
378                 if (cl->cl_f >= cl1->cl_f)
379                         p = &parent->rb_right;
380                 else
381                         p = &parent->rb_left;
382         }
383         rb_link_node(&cl->cf_node, parent, p);
384         rb_insert_color(&cl->cf_node, &cl->cl_parent->cf_tree);
385 }
386
387 static inline void
388 cftree_remove(struct hfsc_class *cl)
389 {
390         rb_erase(&cl->cf_node, &cl->cl_parent->cf_tree);
391 }
392
393 static inline void
394 cftree_update(struct hfsc_class *cl)
395 {
396         cftree_remove(cl);
397         cftree_insert(cl);
398 }
399
400 /*
401  * service curve support functions
402  *
403  *  external service curve parameters
404  *      m: bps
405  *      d: us
406  *  internal service curve parameters
407  *      sm: (bytes/psched_us) << SM_SHIFT
408  *      ism: (psched_us/byte) << ISM_SHIFT
409  *      dx: psched_us
410  *
411  * Clock source resolution (CONFIG_NET_SCH_CLK_*)
412  *  JIFFIES: for 48<=HZ<=1534 resolution is between 0.63us and 1.27us.
413  *  CPU: resolution is between 0.5us and 1us.
414  *  GETTIMEOFDAY: resolution is exactly 1us.
415  *
416  * sm and ism are scaled in order to keep effective digits.
417  * SM_SHIFT and ISM_SHIFT are selected to keep at least 4 effective
418  * digits in decimal using the following table.
419  *
420  * Note: We can afford the additional accuracy (altq hfsc keeps at most
421  * 3 effective digits) thanks to the fact that linux clock is bounded
422  * much more tightly.
423  *
424  *  bits/sec      100Kbps     1Mbps     10Mbps     100Mbps    1Gbps
425  *  ------------+-------------------------------------------------------
426  *  bytes/0.5us   6.25e-3    62.5e-3    625e-3     6250e-e    62500e-3
427  *  bytes/us      12.5e-3    125e-3     1250e-3    12500e-3   125000e-3
428  *  bytes/1.27us  15.875e-3  158.75e-3  1587.5e-3  15875e-3   158750e-3
429  *
430  *  0.5us/byte    160        16         1.6        0.16       0.016
431  *  us/byte       80         8          0.8        0.08       0.008
432  *  1.27us/byte   63         6.3        0.63       0.063      0.0063
433  */
434 #define SM_SHIFT        20
435 #define ISM_SHIFT       18
436
437 #define SM_MASK         ((1ULL << SM_SHIFT) - 1)
438 #define ISM_MASK        ((1ULL << ISM_SHIFT) - 1)
439
440 static inline u64
441 seg_x2y(u64 x, u64 sm)
442 {
443         u64 y;
444
445         /*
446          * compute
447          *      y = x * sm >> SM_SHIFT
448          * but divide it for the upper and lower bits to avoid overflow
449          */
450         y = (x >> SM_SHIFT) * sm + (((x & SM_MASK) * sm) >> SM_SHIFT);
451         return y;
452 }
453
454 static inline u64
455 seg_y2x(u64 y, u64 ism)
456 {
457         u64 x;
458
459         if (y == 0)
460                 x = 0;
461         else if (ism == HT_INFINITY)
462                 x = HT_INFINITY;
463         else {
464                 x = (y >> ISM_SHIFT) * ism
465                     + (((y & ISM_MASK) * ism) >> ISM_SHIFT);
466         }
467         return x;
468 }
469
470 /* Convert m (bps) into sm (bytes/psched us) */
471 static u64
472 m2sm(u32 m)
473 {
474         u64 sm;
475
476         sm = ((u64)m << SM_SHIFT);
477         sm += PSCHED_JIFFIE2US(HZ) - 1;
478         do_div(sm, PSCHED_JIFFIE2US(HZ));
479         return sm;
480 }
481
482 /* convert m (bps) into ism (psched us/byte) */
483 static u64
484 m2ism(u32 m)
485 {
486         u64 ism;
487
488         if (m == 0)
489                 ism = HT_INFINITY;
490         else {
491                 ism = ((u64)PSCHED_JIFFIE2US(HZ) << ISM_SHIFT);
492                 ism += m - 1;
493                 do_div(ism, m);
494         }
495         return ism;
496 }
497
498 /* convert d (us) into dx (psched us) */
499 static u64
500 d2dx(u32 d)
501 {
502         u64 dx;
503
504         dx = ((u64)d * PSCHED_JIFFIE2US(HZ));
505         dx += USEC_PER_SEC - 1;
506         do_div(dx, USEC_PER_SEC);
507         return dx;
508 }
509
510 /* convert sm (bytes/psched us) into m (bps) */
511 static u32
512 sm2m(u64 sm)
513 {
514         u64 m;
515
516         m = (sm * PSCHED_JIFFIE2US(HZ)) >> SM_SHIFT;
517         return (u32)m;
518 }
519
520 /* convert dx (psched us) into d (us) */
521 static u32
522 dx2d(u64 dx)
523 {
524         u64 d;
525
526         d = dx * USEC_PER_SEC;
527         do_div(d, PSCHED_JIFFIE2US(HZ));
528         return (u32)d;
529 }
530
531 static void
532 sc2isc(struct tc_service_curve *sc, struct internal_sc *isc)
533 {
534         isc->sm1  = m2sm(sc->m1);
535         isc->ism1 = m2ism(sc->m1);
536         isc->dx   = d2dx(sc->d);
537         isc->dy   = seg_x2y(isc->dx, isc->sm1);
538         isc->sm2  = m2sm(sc->m2);
539         isc->ism2 = m2ism(sc->m2);
540 }
541
542 /*
543  * initialize the runtime service curve with the given internal
544  * service curve starting at (x, y).
545  */
546 static void
547 rtsc_init(struct runtime_sc *rtsc, struct internal_sc *isc, u64 x, u64 y)
548 {
549         rtsc->x    = x;
550         rtsc->y    = y;
551         rtsc->sm1  = isc->sm1;
552         rtsc->ism1 = isc->ism1;
553         rtsc->dx   = isc->dx;
554         rtsc->dy   = isc->dy;
555         rtsc->sm2  = isc->sm2;
556         rtsc->ism2 = isc->ism2;
557 }
558
559 /*
560  * calculate the y-projection of the runtime service curve by the
561  * given x-projection value
562  */
563 static u64
564 rtsc_y2x(struct runtime_sc *rtsc, u64 y)
565 {
566         u64 x;
567
568         if (y < rtsc->y)
569                 x = rtsc->x;
570         else if (y <= rtsc->y + rtsc->dy) {
571                 /* x belongs to the 1st segment */
572                 if (rtsc->dy == 0)
573                         x = rtsc->x + rtsc->dx;
574                 else
575                         x = rtsc->x + seg_y2x(y - rtsc->y, rtsc->ism1);
576         } else {
577                 /* x belongs to the 2nd segment */
578                 x = rtsc->x + rtsc->dx
579                     + seg_y2x(y - rtsc->y - rtsc->dy, rtsc->ism2);
580         }
581         return x;
582 }
583
584 static u64
585 rtsc_x2y(struct runtime_sc *rtsc, u64 x)
586 {
587         u64 y;
588
589         if (x <= rtsc->x)
590                 y = rtsc->y;
591         else if (x <= rtsc->x + rtsc->dx)
592                 /* y belongs to the 1st segment */
593                 y = rtsc->y + seg_x2y(x - rtsc->x, rtsc->sm1);
594         else
595                 /* y belongs to the 2nd segment */
596                 y = rtsc->y + rtsc->dy
597                     + seg_x2y(x - rtsc->x - rtsc->dx, rtsc->sm2);
598         return y;
599 }
600
601 /*
602  * update the runtime service curve by taking the minimum of the current
603  * runtime service curve and the service curve starting at (x, y).
604  */
605 static void
606 rtsc_min(struct runtime_sc *rtsc, struct internal_sc *isc, u64 x, u64 y)
607 {
608         u64 y1, y2, dx, dy;
609         u32 dsm;
610
611         if (isc->sm1 <= isc->sm2) {
612                 /* service curve is convex */
613                 y1 = rtsc_x2y(rtsc, x);
614                 if (y1 < y)
615                         /* the current rtsc is smaller */
616                         return;
617                 rtsc->x = x;
618                 rtsc->y = y;
619                 return;
620         }
621
622         /*
623          * service curve is concave
624          * compute the two y values of the current rtsc
625          *      y1: at x
626          *      y2: at (x + dx)
627          */
628         y1 = rtsc_x2y(rtsc, x);
629         if (y1 <= y) {
630                 /* rtsc is below isc, no change to rtsc */
631                 return;
632         }
633
634         y2 = rtsc_x2y(rtsc, x + isc->dx);
635         if (y2 >= y + isc->dy) {
636                 /* rtsc is above isc, replace rtsc by isc */
637                 rtsc->x = x;
638                 rtsc->y = y;
639                 rtsc->dx = isc->dx;
640                 rtsc->dy = isc->dy;
641                 return;
642         }
643
644         /*
645          * the two curves intersect
646          * compute the offsets (dx, dy) using the reverse
647          * function of seg_x2y()
648          *      seg_x2y(dx, sm1) == seg_x2y(dx, sm2) + (y1 - y)
649          */
650         dx = (y1 - y) << SM_SHIFT;
651         dsm = isc->sm1 - isc->sm2;
652         do_div(dx, dsm);
653         /*
654          * check if (x, y1) belongs to the 1st segment of rtsc.
655          * if so, add the offset.
656          */
657         if (rtsc->x + rtsc->dx > x)
658                 dx += rtsc->x + rtsc->dx - x;
659         dy = seg_x2y(dx, isc->sm1);
660
661         rtsc->x = x;
662         rtsc->y = y;
663         rtsc->dx = dx;
664         rtsc->dy = dy;
665         return;
666 }
667
668 static void
669 init_ed(struct hfsc_class *cl, unsigned int next_len)
670 {
671         u64 cur_time;
672
673         PSCHED_GET_TIME(cur_time);
674
675         /* update the deadline curve */
676         rtsc_min(&cl->cl_deadline, &cl->cl_rsc, cur_time, cl->cl_cumul);
677
678         /*
679          * update the eligible curve.
680          * for concave, it is equal to the deadline curve.
681          * for convex, it is a linear curve with slope m2.
682          */
683         cl->cl_eligible = cl->cl_deadline;
684         if (cl->cl_rsc.sm1 <= cl->cl_rsc.sm2) {
685                 cl->cl_eligible.dx = 0;
686                 cl->cl_eligible.dy = 0;
687         }
688
689         /* compute e and d */
690         cl->cl_e = rtsc_y2x(&cl->cl_eligible, cl->cl_cumul);
691         cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
692
693         eltree_insert(cl);
694 }
695
696 static void
697 update_ed(struct hfsc_class *cl, unsigned int next_len)
698 {
699         cl->cl_e = rtsc_y2x(&cl->cl_eligible, cl->cl_cumul);
700         cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
701
702         eltree_update(cl);
703 }
704
705 static inline void
706 update_d(struct hfsc_class *cl, unsigned int next_len)
707 {
708         cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
709 }
710
711 static inline void
712 update_cfmin(struct hfsc_class *cl)
713 {
714         struct rb_node *n = rb_first(&cl->cf_tree);
715         struct hfsc_class *p;
716
717         if (n == NULL) {
718                 cl->cl_cfmin = 0;
719                 return;
720         }
721         p = rb_entry(n, struct hfsc_class, cf_node);
722         cl->cl_cfmin = p->cl_f;
723 }
724
725 static void
726 init_vf(struct hfsc_class *cl, unsigned int len)
727 {
728         struct hfsc_class *max_cl;
729         struct rb_node *n;
730         u64 vt, f, cur_time;
731         int go_active;
732
733         cur_time = 0;
734         go_active = 1;
735         for (; cl->cl_parent != NULL; cl = cl->cl_parent) {
736                 if (go_active && cl->cl_nactive++ == 0)
737                         go_active = 1;
738                 else
739                         go_active = 0;
740
741                 if (go_active) {
742                         n = rb_last(&cl->cl_parent->vt_tree);
743                         if (n != NULL) {
744                                 max_cl = rb_entry(n, struct hfsc_class,vt_node);
745                                 /*
746                                  * set vt to the average of the min and max
747                                  * classes.  if the parent's period didn't
748                                  * change, don't decrease vt of the class.
749                                  */
750                                 vt = max_cl->cl_vt;
751                                 if (cl->cl_parent->cl_cvtmin != 0)
752                                         vt = (cl->cl_parent->cl_cvtmin + vt)/2;
753
754                                 if (cl->cl_parent->cl_vtperiod !=
755                                     cl->cl_parentperiod || vt > cl->cl_vt)
756                                         cl->cl_vt = vt;
757                         } else {
758                                 /*
759                                  * first child for a new parent backlog period.
760                                  * add parent's cvtmax to cvtoff to make a new
761                                  * vt (vtoff + vt) larger than the vt in the
762                                  * last period for all children.
763                                  */
764                                 vt = cl->cl_parent->cl_cvtmax;
765                                 cl->cl_parent->cl_cvtoff += vt;
766                                 cl->cl_parent->cl_cvtmax = 0;
767                                 cl->cl_parent->cl_cvtmin = 0;
768                                 cl->cl_vt = 0;
769                         }
770
771                         cl->cl_vtoff = cl->cl_parent->cl_cvtoff -
772                                                         cl->cl_pcvtoff;
773
774                         /* update the virtual curve */
775                         vt = cl->cl_vt + cl->cl_vtoff;
776                         rtsc_min(&cl->cl_virtual, &cl->cl_fsc, vt,
777                                                       cl->cl_total);
778                         if (cl->cl_virtual.x == vt) {
779                                 cl->cl_virtual.x -= cl->cl_vtoff;
780                                 cl->cl_vtoff = 0;
781                         }
782                         cl->cl_vtadj = 0;
783
784                         cl->cl_vtperiod++;  /* increment vt period */
785                         cl->cl_parentperiod = cl->cl_parent->cl_vtperiod;
786                         if (cl->cl_parent->cl_nactive == 0)
787                                 cl->cl_parentperiod++;
788                         cl->cl_f = 0;
789
790                         vttree_insert(cl);
791                         cftree_insert(cl);
792
793                         if (cl->cl_flags & HFSC_USC) {
794                                 /* class has upper limit curve */
795                                 if (cur_time == 0)
796                                         PSCHED_GET_TIME(cur_time);
797
798                                 /* update the ulimit curve */
799                                 rtsc_min(&cl->cl_ulimit, &cl->cl_usc, cur_time,
800                                          cl->cl_total);
801                                 /* compute myf */
802                                 cl->cl_myf = rtsc_y2x(&cl->cl_ulimit,
803                                                       cl->cl_total);
804                                 cl->cl_myfadj = 0;
805                         }
806                 }
807
808                 f = max(cl->cl_myf, cl->cl_cfmin);
809                 if (f != cl->cl_f) {
810                         cl->cl_f = f;
811                         cftree_update(cl);
812                         update_cfmin(cl->cl_parent);
813                 }
814         }
815 }
816
817 static void
818 update_vf(struct hfsc_class *cl, unsigned int len, u64 cur_time)
819 {
820         u64 f; /* , myf_bound, delta; */
821         int go_passive = 0;
822
823         if (cl->qdisc->q.qlen == 0 && cl->cl_flags & HFSC_FSC)
824                 go_passive = 1;
825
826         for (; cl->cl_parent != NULL; cl = cl->cl_parent) {
827                 cl->cl_total += len;
828
829                 if (!(cl->cl_flags & HFSC_FSC) || cl->cl_nactive == 0)
830                         continue;
831
832                 if (go_passive && --cl->cl_nactive == 0)
833                         go_passive = 1;
834                 else
835                         go_passive = 0;
836
837                 if (go_passive) {
838                         /* no more active child, going passive */
839
840                         /* update cvtmax of the parent class */
841                         if (cl->cl_vt > cl->cl_parent->cl_cvtmax)
842                                 cl->cl_parent->cl_cvtmax = cl->cl_vt;
843
844                         /* remove this class from the vt tree */
845                         vttree_remove(cl);
846
847                         cftree_remove(cl);
848                         update_cfmin(cl->cl_parent);
849
850                         continue;
851                 }
852
853                 /*
854                  * update vt and f
855                  */
856                 cl->cl_vt = rtsc_y2x(&cl->cl_virtual, cl->cl_total)
857                             - cl->cl_vtoff + cl->cl_vtadj;
858
859                 /*
860                  * if vt of the class is smaller than cvtmin,
861                  * the class was skipped in the past due to non-fit.
862                  * if so, we need to adjust vtadj.
863                  */
864                 if (cl->cl_vt < cl->cl_parent->cl_cvtmin) {
865                         cl->cl_vtadj += cl->cl_parent->cl_cvtmin - cl->cl_vt;
866                         cl->cl_vt = cl->cl_parent->cl_cvtmin;
867                 }
868
869                 /* update the vt tree */
870                 vttree_update(cl);
871
872                 if (cl->cl_flags & HFSC_USC) {
873                         cl->cl_myf = cl->cl_myfadj + rtsc_y2x(&cl->cl_ulimit,
874                                                               cl->cl_total);
875 #if 0
876                         /*
877                          * This code causes classes to stay way under their
878                          * limit when multiple classes are used at gigabit
879                          * speed. needs investigation. -kaber
880                          */
881                         /*
882                          * if myf lags behind by more than one clock tick
883                          * from the current time, adjust myfadj to prevent
884                          * a rate-limited class from going greedy.
885                          * in a steady state under rate-limiting, myf
886                          * fluctuates within one clock tick.
887                          */
888                         myf_bound = cur_time - PSCHED_JIFFIE2US(1);
889                         if (cl->cl_myf < myf_bound) {
890                                 delta = cur_time - cl->cl_myf;
891                                 cl->cl_myfadj += delta;
892                                 cl->cl_myf += delta;
893                         }
894 #endif
895                 }
896
897                 f = max(cl->cl_myf, cl->cl_cfmin);
898                 if (f != cl->cl_f) {
899                         cl->cl_f = f;
900                         cftree_update(cl);
901                         update_cfmin(cl->cl_parent);
902                 }
903         }
904 }
905
906 static void
907 set_active(struct hfsc_class *cl, unsigned int len)
908 {
909         if (cl->cl_flags & HFSC_RSC)
910                 init_ed(cl, len);
911         if (cl->cl_flags & HFSC_FSC)
912                 init_vf(cl, len);
913
914         list_add_tail(&cl->dlist, &cl->sched->droplist);
915 }
916
917 static void
918 set_passive(struct hfsc_class *cl)
919 {
920         if (cl->cl_flags & HFSC_RSC)
921                 eltree_remove(cl);
922
923         list_del(&cl->dlist);
924
925         /*
926          * vttree is now handled in update_vf() so that update_vf(cl, 0, 0)
927          * needs to be called explicitly to remove a class from vttree.
928          */
929 }
930
931 /*
932  * hack to get length of first packet in queue.
933  */
934 static unsigned int
935 qdisc_peek_len(struct Qdisc *sch)
936 {
937         struct sk_buff *skb;
938         unsigned int len;
939
940         skb = sch->dequeue(sch);
941         if (skb == NULL) {
942                 if (net_ratelimit())
943                         printk("qdisc_peek_len: non work-conserving qdisc ?\n");
944                 return 0;
945         }
946         len = skb->len;
947         if (unlikely(sch->ops->requeue(skb, sch) != NET_XMIT_SUCCESS)) {
948                 if (net_ratelimit())
949                         printk("qdisc_peek_len: failed to requeue\n");
950                 return 0;
951         }
952         return len;
953 }
954
955 static void
956 hfsc_purge_queue(struct Qdisc *sch, struct hfsc_class *cl)
957 {
958         unsigned int len = cl->qdisc->q.qlen;
959
960         qdisc_reset(cl->qdisc);
961         if (len > 0) {
962                 update_vf(cl, 0, 0);
963                 set_passive(cl);
964                 sch->q.qlen -= len;
965         }
966 }
967
968 static void
969 hfsc_adjust_levels(struct hfsc_class *cl)
970 {
971         struct hfsc_class *p;
972         unsigned int level;
973
974         do {
975                 level = 0;
976                 list_for_each_entry(p, &cl->children, siblings) {
977                         if (p->level >= level)
978                                 level = p->level + 1;
979                 }
980                 cl->level = level;
981         } while ((cl = cl->cl_parent) != NULL);
982 }
983
984 static inline unsigned int
985 hfsc_hash(u32 h)
986 {
987         h ^= h >> 8;
988         h ^= h >> 4;
989
990         return h & (HFSC_HSIZE - 1);
991 }
992
993 static inline struct hfsc_class *
994 hfsc_find_class(u32 classid, struct Qdisc *sch)
995 {
996         struct hfsc_sched *q = qdisc_priv(sch);
997         struct hfsc_class *cl;
998
999         list_for_each_entry(cl, &q->clhash[hfsc_hash(classid)], hlist) {
1000                 if (cl->classid == classid)
1001                         return cl;
1002         }
1003         return NULL;
1004 }
1005
1006 static void
1007 hfsc_change_rsc(struct hfsc_class *cl, struct tc_service_curve *rsc,
1008                 u64 cur_time)
1009 {
1010         sc2isc(rsc, &cl->cl_rsc);
1011         rtsc_init(&cl->cl_deadline, &cl->cl_rsc, cur_time, cl->cl_cumul);
1012         cl->cl_eligible = cl->cl_deadline;
1013         if (cl->cl_rsc.sm1 <= cl->cl_rsc.sm2) {
1014                 cl->cl_eligible.dx = 0;
1015                 cl->cl_eligible.dy = 0;
1016         }
1017         cl->cl_flags |= HFSC_RSC;
1018 }
1019
1020 static void
1021 hfsc_change_fsc(struct hfsc_class *cl, struct tc_service_curve *fsc)
1022 {
1023         sc2isc(fsc, &cl->cl_fsc);
1024         rtsc_init(&cl->cl_virtual, &cl->cl_fsc, cl->cl_vt, cl->cl_total);
1025         cl->cl_flags |= HFSC_FSC;
1026 }
1027
1028 static void
1029 hfsc_change_usc(struct hfsc_class *cl, struct tc_service_curve *usc,
1030                 u64 cur_time)
1031 {
1032         sc2isc(usc, &cl->cl_usc);
1033         rtsc_init(&cl->cl_ulimit, &cl->cl_usc, cur_time, cl->cl_total);
1034         cl->cl_flags |= HFSC_USC;
1035 }
1036
1037 static int
1038 hfsc_change_class(struct Qdisc *sch, u32 classid, u32 parentid,
1039                   struct rtattr **tca, unsigned long *arg)
1040 {
1041         struct hfsc_sched *q = qdisc_priv(sch);
1042         struct hfsc_class *cl = (struct hfsc_class *)*arg;
1043         struct hfsc_class *parent = NULL;
1044         struct rtattr *opt = tca[TCA_OPTIONS-1];
1045         struct rtattr *tb[TCA_HFSC_MAX];
1046         struct tc_service_curve *rsc = NULL, *fsc = NULL, *usc = NULL;
1047         u64 cur_time;
1048
1049         if (opt == NULL || rtattr_parse_nested(tb, TCA_HFSC_MAX, opt))
1050                 return -EINVAL;
1051
1052         if (tb[TCA_HFSC_RSC-1]) {
1053                 if (RTA_PAYLOAD(tb[TCA_HFSC_RSC-1]) < sizeof(*rsc))
1054                         return -EINVAL;
1055                 rsc = RTA_DATA(tb[TCA_HFSC_RSC-1]);
1056                 if (rsc->m1 == 0 && rsc->m2 == 0)
1057                         rsc = NULL;
1058         }
1059
1060         if (tb[TCA_HFSC_FSC-1]) {
1061                 if (RTA_PAYLOAD(tb[TCA_HFSC_FSC-1]) < sizeof(*fsc))
1062                         return -EINVAL;
1063                 fsc = RTA_DATA(tb[TCA_HFSC_FSC-1]);
1064                 if (fsc->m1 == 0 && fsc->m2 == 0)
1065                         fsc = NULL;
1066         }
1067
1068         if (tb[TCA_HFSC_USC-1]) {
1069                 if (RTA_PAYLOAD(tb[TCA_HFSC_USC-1]) < sizeof(*usc))
1070                         return -EINVAL;
1071                 usc = RTA_DATA(tb[TCA_HFSC_USC-1]);
1072                 if (usc->m1 == 0 && usc->m2 == 0)
1073                         usc = NULL;
1074         }
1075
1076         if (cl != NULL) {
1077                 if (parentid) {
1078                         if (cl->cl_parent && cl->cl_parent->classid != parentid)
1079                                 return -EINVAL;
1080                         if (cl->cl_parent == NULL && parentid != TC_H_ROOT)
1081                                 return -EINVAL;
1082                 }
1083                 PSCHED_GET_TIME(cur_time);
1084
1085                 sch_tree_lock(sch);
1086                 if (rsc != NULL)
1087                         hfsc_change_rsc(cl, rsc, cur_time);
1088                 if (fsc != NULL)
1089                         hfsc_change_fsc(cl, fsc);
1090                 if (usc != NULL)
1091                         hfsc_change_usc(cl, usc, cur_time);
1092
1093                 if (cl->qdisc->q.qlen != 0) {
1094                         if (cl->cl_flags & HFSC_RSC)
1095                                 update_ed(cl, qdisc_peek_len(cl->qdisc));
1096                         if (cl->cl_flags & HFSC_FSC)
1097                                 update_vf(cl, 0, cur_time);
1098                 }
1099                 sch_tree_unlock(sch);
1100
1101 #ifdef CONFIG_NET_ESTIMATOR
1102                 if (tca[TCA_RATE-1])
1103                         gen_replace_estimator(&cl->bstats, &cl->rate_est,
1104                                 cl->stats_lock, tca[TCA_RATE-1]);
1105 #endif
1106                 return 0;
1107         }
1108
1109         if (parentid == TC_H_ROOT)
1110                 return -EEXIST;
1111
1112         parent = &q->root;
1113         if (parentid) {
1114                 parent = hfsc_find_class(parentid, sch);
1115                 if (parent == NULL)
1116                         return -ENOENT;
1117         }
1118
1119         if (classid == 0 || TC_H_MAJ(classid ^ sch->handle) != 0)
1120                 return -EINVAL;
1121         if (hfsc_find_class(classid, sch))
1122                 return -EEXIST;
1123
1124         if (rsc == NULL && fsc == NULL)
1125                 return -EINVAL;
1126
1127         cl = kmalloc(sizeof(struct hfsc_class), GFP_KERNEL);
1128         if (cl == NULL)
1129                 return -ENOBUFS;
1130         memset(cl, 0, sizeof(struct hfsc_class));
1131
1132         if (rsc != NULL)
1133                 hfsc_change_rsc(cl, rsc, 0);
1134         if (fsc != NULL)
1135                 hfsc_change_fsc(cl, fsc);
1136         if (usc != NULL)
1137                 hfsc_change_usc(cl, usc, 0);
1138
1139         cl->refcnt    = 1;
1140         cl->classid   = classid;
1141         cl->sched     = q;
1142         cl->cl_parent = parent;
1143         cl->qdisc = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops);
1144         if (cl->qdisc == NULL)
1145                 cl->qdisc = &noop_qdisc;
1146         cl->stats_lock = &sch->dev->queue_lock;
1147         INIT_LIST_HEAD(&cl->children);
1148         cl->vt_tree = RB_ROOT;
1149         cl->cf_tree = RB_ROOT;
1150
1151         sch_tree_lock(sch);
1152         list_add_tail(&cl->hlist, &q->clhash[hfsc_hash(classid)]);
1153         list_add_tail(&cl->siblings, &parent->children);
1154         if (parent->level == 0)
1155                 hfsc_purge_queue(sch, parent);
1156         hfsc_adjust_levels(parent);
1157         cl->cl_pcvtoff = parent->cl_cvtoff;
1158         sch_tree_unlock(sch);
1159
1160 #ifdef CONFIG_NET_ESTIMATOR
1161         if (tca[TCA_RATE-1])
1162                 gen_new_estimator(&cl->bstats, &cl->rate_est,
1163                         cl->stats_lock, tca[TCA_RATE-1]);
1164 #endif
1165         *arg = (unsigned long)cl;
1166         return 0;
1167 }
1168
1169 static void
1170 hfsc_destroy_filters(struct tcf_proto **fl)
1171 {
1172         struct tcf_proto *tp;
1173
1174         while ((tp = *fl) != NULL) {
1175                 *fl = tp->next;
1176                 tcf_destroy(tp);
1177         }
1178 }
1179
1180 static void
1181 hfsc_destroy_class(struct Qdisc *sch, struct hfsc_class *cl)
1182 {
1183         struct hfsc_sched *q = qdisc_priv(sch);
1184
1185         hfsc_destroy_filters(&cl->filter_list);
1186         qdisc_destroy(cl->qdisc);
1187 #ifdef CONFIG_NET_ESTIMATOR
1188         gen_kill_estimator(&cl->bstats, &cl->rate_est);
1189 #endif
1190         if (cl != &q->root)
1191                 kfree(cl);
1192 }
1193
1194 static int
1195 hfsc_delete_class(struct Qdisc *sch, unsigned long arg)
1196 {
1197         struct hfsc_sched *q = qdisc_priv(sch);
1198         struct hfsc_class *cl = (struct hfsc_class *)arg;
1199
1200         if (cl->level > 0 || cl->filter_cnt > 0 || cl == &q->root)
1201                 return -EBUSY;
1202
1203         sch_tree_lock(sch);
1204
1205         list_del(&cl->hlist);
1206         list_del(&cl->siblings);
1207         hfsc_adjust_levels(cl->cl_parent);
1208         hfsc_purge_queue(sch, cl);
1209         if (--cl->refcnt == 0)
1210                 hfsc_destroy_class(sch, cl);
1211
1212         sch_tree_unlock(sch);
1213         return 0;
1214 }
1215
1216 static struct hfsc_class *
1217 hfsc_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
1218 {
1219         struct hfsc_sched *q = qdisc_priv(sch);
1220         struct hfsc_class *cl;
1221         struct tcf_result res;
1222         struct tcf_proto *tcf;
1223         int result;
1224
1225         if (TC_H_MAJ(skb->priority ^ sch->handle) == 0 &&
1226             (cl = hfsc_find_class(skb->priority, sch)) != NULL)
1227                 if (cl->level == 0)
1228                         return cl;
1229
1230         *qerr = NET_XMIT_BYPASS;
1231         tcf = q->root.filter_list;
1232         while (tcf && (result = tc_classify(skb, tcf, &res)) >= 0) {
1233 #ifdef CONFIG_NET_CLS_ACT
1234                 switch (result) {
1235                 case TC_ACT_QUEUED:
1236                 case TC_ACT_STOLEN: 
1237                         *qerr = NET_XMIT_SUCCESS;
1238                 case TC_ACT_SHOT: 
1239                         return NULL;
1240                 }
1241 #elif defined(CONFIG_NET_CLS_POLICE)
1242                 if (result == TC_POLICE_SHOT)
1243                         return NULL;
1244 #endif
1245                 if ((cl = (struct hfsc_class *)res.class) == NULL) {
1246                         if ((cl = hfsc_find_class(res.classid, sch)) == NULL)
1247                                 break; /* filter selected invalid classid */
1248                 }
1249
1250                 if (cl->level == 0)
1251                         return cl; /* hit leaf class */
1252
1253                 /* apply inner filter chain */
1254                 tcf = cl->filter_list;
1255         }
1256
1257         /* classification failed, try default class */
1258         cl = hfsc_find_class(TC_H_MAKE(TC_H_MAJ(sch->handle), q->defcls), sch);
1259         if (cl == NULL || cl->level > 0)
1260                 return NULL;
1261
1262         return cl;
1263 }
1264
1265 static int
1266 hfsc_graft_class(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
1267                  struct Qdisc **old)
1268 {
1269         struct hfsc_class *cl = (struct hfsc_class *)arg;
1270
1271         if (cl == NULL)
1272                 return -ENOENT;
1273         if (cl->level > 0)
1274                 return -EINVAL;
1275         if (new == NULL) {
1276                 new = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops);
1277                 if (new == NULL)
1278                         new = &noop_qdisc;
1279         }
1280
1281         sch_tree_lock(sch);
1282         hfsc_purge_queue(sch, cl);
1283         *old = xchg(&cl->qdisc, new);
1284         sch_tree_unlock(sch);
1285         return 0;
1286 }
1287
1288 static struct Qdisc *
1289 hfsc_class_leaf(struct Qdisc *sch, unsigned long arg)
1290 {
1291         struct hfsc_class *cl = (struct hfsc_class *)arg;
1292
1293         if (cl != NULL && cl->level == 0)
1294                 return cl->qdisc;
1295
1296         return NULL;
1297 }
1298
1299 static unsigned long
1300 hfsc_get_class(struct Qdisc *sch, u32 classid)
1301 {
1302         struct hfsc_class *cl = hfsc_find_class(classid, sch);
1303
1304         if (cl != NULL)
1305                 cl->refcnt++;
1306
1307         return (unsigned long)cl;
1308 }
1309
1310 static void
1311 hfsc_put_class(struct Qdisc *sch, unsigned long arg)
1312 {
1313         struct hfsc_class *cl = (struct hfsc_class *)arg;
1314
1315         if (--cl->refcnt == 0)
1316                 hfsc_destroy_class(sch, cl);
1317 }
1318
1319 static unsigned long
1320 hfsc_bind_tcf(struct Qdisc *sch, unsigned long parent, u32 classid)
1321 {
1322         struct hfsc_class *p = (struct hfsc_class *)parent;
1323         struct hfsc_class *cl = hfsc_find_class(classid, sch);
1324
1325         if (cl != NULL) {
1326                 if (p != NULL && p->level <= cl->level)
1327                         return 0;
1328                 cl->filter_cnt++;
1329         }
1330
1331         return (unsigned long)cl;
1332 }
1333
1334 static void
1335 hfsc_unbind_tcf(struct Qdisc *sch, unsigned long arg)
1336 {
1337         struct hfsc_class *cl = (struct hfsc_class *)arg;
1338
1339         cl->filter_cnt--;
1340 }
1341
1342 static struct tcf_proto **
1343 hfsc_tcf_chain(struct Qdisc *sch, unsigned long arg)
1344 {
1345         struct hfsc_sched *q = qdisc_priv(sch);
1346         struct hfsc_class *cl = (struct hfsc_class *)arg;
1347
1348         if (cl == NULL)
1349                 cl = &q->root;
1350
1351         return &cl->filter_list;
1352 }
1353
1354 static int
1355 hfsc_dump_sc(struct sk_buff *skb, int attr, struct internal_sc *sc)
1356 {
1357         struct tc_service_curve tsc;
1358
1359         tsc.m1 = sm2m(sc->sm1);
1360         tsc.d  = dx2d(sc->dx);
1361         tsc.m2 = sm2m(sc->sm2);
1362         RTA_PUT(skb, attr, sizeof(tsc), &tsc);
1363
1364         return skb->len;
1365
1366  rtattr_failure:
1367         return -1;
1368 }
1369
1370 static inline int
1371 hfsc_dump_curves(struct sk_buff *skb, struct hfsc_class *cl)
1372 {
1373         if ((cl->cl_flags & HFSC_RSC) &&
1374             (hfsc_dump_sc(skb, TCA_HFSC_RSC, &cl->cl_rsc) < 0))
1375                 goto rtattr_failure;
1376
1377         if ((cl->cl_flags & HFSC_FSC) &&
1378             (hfsc_dump_sc(skb, TCA_HFSC_FSC, &cl->cl_fsc) < 0))
1379                 goto rtattr_failure;
1380
1381         if ((cl->cl_flags & HFSC_USC) &&
1382             (hfsc_dump_sc(skb, TCA_HFSC_USC, &cl->cl_usc) < 0))
1383                 goto rtattr_failure;
1384
1385         return skb->len;
1386
1387  rtattr_failure:
1388         return -1;
1389 }
1390
1391 static int
1392 hfsc_dump_class(struct Qdisc *sch, unsigned long arg, struct sk_buff *skb,
1393                 struct tcmsg *tcm)
1394 {
1395         struct hfsc_class *cl = (struct hfsc_class *)arg;
1396         unsigned char *b = skb->tail;
1397         struct rtattr *rta = (struct rtattr *)b;
1398
1399         tcm->tcm_parent = cl->cl_parent ? cl->cl_parent->classid : TC_H_ROOT;
1400         tcm->tcm_handle = cl->classid;
1401         if (cl->level == 0)
1402                 tcm->tcm_info = cl->qdisc->handle;
1403
1404         RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
1405         if (hfsc_dump_curves(skb, cl) < 0)
1406                 goto rtattr_failure;
1407         rta->rta_len = skb->tail - b;
1408         return skb->len;
1409
1410  rtattr_failure:
1411         skb_trim(skb, b - skb->data);
1412         return -1;
1413 }
1414
1415 static int
1416 hfsc_dump_class_stats(struct Qdisc *sch, unsigned long arg,
1417         struct gnet_dump *d)
1418 {
1419         struct hfsc_class *cl = (struct hfsc_class *)arg;
1420         struct tc_hfsc_stats xstats;
1421
1422         cl->qstats.qlen = cl->qdisc->q.qlen;
1423         xstats.level   = cl->level;
1424         xstats.period  = cl->cl_vtperiod;
1425         xstats.work    = cl->cl_total;
1426         xstats.rtwork  = cl->cl_cumul;
1427
1428         if (gnet_stats_copy_basic(d, &cl->bstats) < 0 ||
1429 #ifdef CONFIG_NET_ESTIMATOR
1430             gnet_stats_copy_rate_est(d, &cl->rate_est) < 0 ||
1431 #endif
1432             gnet_stats_copy_queue(d, &cl->qstats) < 0)
1433                 return -1;
1434
1435         return gnet_stats_copy_app(d, &xstats, sizeof(xstats));
1436 }
1437
1438
1439
1440 static void
1441 hfsc_walk(struct Qdisc *sch, struct qdisc_walker *arg)
1442 {
1443         struct hfsc_sched *q = qdisc_priv(sch);
1444         struct hfsc_class *cl;
1445         unsigned int i;
1446
1447         if (arg->stop)
1448                 return;
1449
1450         for (i = 0; i < HFSC_HSIZE; i++) {
1451                 list_for_each_entry(cl, &q->clhash[i], hlist) {
1452                         if (arg->count < arg->skip) {
1453                                 arg->count++;
1454                                 continue;
1455                         }
1456                         if (arg->fn(sch, (unsigned long)cl, arg) < 0) {
1457                                 arg->stop = 1;
1458                                 return;
1459                         }
1460                         arg->count++;
1461                 }
1462         }
1463 }
1464
1465 static void
1466 hfsc_watchdog(unsigned long arg)
1467 {
1468         struct Qdisc *sch = (struct Qdisc *)arg;
1469
1470         sch->flags &= ~TCQ_F_THROTTLED;
1471         netif_schedule(sch->dev);
1472 }
1473
1474 static void
1475 hfsc_schedule_watchdog(struct Qdisc *sch, u64 cur_time)
1476 {
1477         struct hfsc_sched *q = qdisc_priv(sch);
1478         struct hfsc_class *cl;
1479         u64 next_time = 0;
1480         long delay;
1481
1482         if ((cl = eltree_get_minel(q)) != NULL)
1483                 next_time = cl->cl_e;
1484         if (q->root.cl_cfmin != 0) {
1485                 if (next_time == 0 || next_time > q->root.cl_cfmin)
1486                         next_time = q->root.cl_cfmin;
1487         }
1488         ASSERT(next_time != 0);
1489         delay = next_time - cur_time;
1490         delay = PSCHED_US2JIFFIE(delay);
1491
1492         sch->flags |= TCQ_F_THROTTLED;
1493         mod_timer(&q->wd_timer, jiffies + delay);
1494 }
1495
1496 static int
1497 hfsc_init_qdisc(struct Qdisc *sch, struct rtattr *opt)
1498 {
1499         struct hfsc_sched *q = qdisc_priv(sch);
1500         struct tc_hfsc_qopt *qopt;
1501         unsigned int i;
1502
1503         if (opt == NULL || RTA_PAYLOAD(opt) < sizeof(*qopt))
1504                 return -EINVAL;
1505         qopt = RTA_DATA(opt);
1506
1507         sch->stats_lock = &sch->dev->queue_lock;
1508
1509         q->defcls = qopt->defcls;
1510         for (i = 0; i < HFSC_HSIZE; i++)
1511                 INIT_LIST_HEAD(&q->clhash[i]);
1512         q->eligible = RB_ROOT;
1513         INIT_LIST_HEAD(&q->droplist);
1514         skb_queue_head_init(&q->requeue);
1515
1516         q->root.refcnt  = 1;
1517         q->root.classid = sch->handle;
1518         q->root.sched   = q;
1519         q->root.qdisc = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops);
1520         if (q->root.qdisc == NULL)
1521                 q->root.qdisc = &noop_qdisc;
1522         q->root.stats_lock = &sch->dev->queue_lock;
1523         INIT_LIST_HEAD(&q->root.children);
1524         q->root.vt_tree = RB_ROOT;
1525         q->root.cf_tree = RB_ROOT;
1526
1527         list_add(&q->root.hlist, &q->clhash[hfsc_hash(q->root.classid)]);
1528
1529         init_timer(&q->wd_timer);
1530         q->wd_timer.function = hfsc_watchdog;
1531         q->wd_timer.data = (unsigned long)sch;
1532
1533         return 0;
1534 }
1535
1536 static int
1537 hfsc_change_qdisc(struct Qdisc *sch, struct rtattr *opt)
1538 {
1539         struct hfsc_sched *q = qdisc_priv(sch);
1540         struct tc_hfsc_qopt *qopt;
1541
1542         if (opt == NULL || RTA_PAYLOAD(opt) < sizeof(*qopt))
1543                 return -EINVAL;
1544         qopt = RTA_DATA(opt);
1545
1546         sch_tree_lock(sch);
1547         q->defcls = qopt->defcls;
1548         sch_tree_unlock(sch);
1549
1550         return 0;
1551 }
1552
1553 static void
1554 hfsc_reset_class(struct hfsc_class *cl)
1555 {
1556         cl->cl_total        = 0;
1557         cl->cl_cumul        = 0;
1558         cl->cl_d            = 0;
1559         cl->cl_e            = 0;
1560         cl->cl_vt           = 0;
1561         cl->cl_vtadj        = 0;
1562         cl->cl_vtoff        = 0;
1563         cl->cl_cvtmin       = 0;
1564         cl->cl_cvtmax       = 0;
1565         cl->cl_cvtoff       = 0;
1566         cl->cl_pcvtoff      = 0;
1567         cl->cl_vtperiod     = 0;
1568         cl->cl_parentperiod = 0;
1569         cl->cl_f            = 0;
1570         cl->cl_myf          = 0;
1571         cl->cl_myfadj       = 0;
1572         cl->cl_cfmin        = 0;
1573         cl->cl_nactive      = 0;
1574
1575         cl->vt_tree = RB_ROOT;
1576         cl->cf_tree = RB_ROOT;
1577         qdisc_reset(cl->qdisc);
1578
1579         if (cl->cl_flags & HFSC_RSC)
1580                 rtsc_init(&cl->cl_deadline, &cl->cl_rsc, 0, 0);
1581         if (cl->cl_flags & HFSC_FSC)
1582                 rtsc_init(&cl->cl_virtual, &cl->cl_fsc, 0, 0);
1583         if (cl->cl_flags & HFSC_USC)
1584                 rtsc_init(&cl->cl_ulimit, &cl->cl_usc, 0, 0);
1585 }
1586
1587 static void
1588 hfsc_reset_qdisc(struct Qdisc *sch)
1589 {
1590         struct hfsc_sched *q = qdisc_priv(sch);
1591         struct hfsc_class *cl;
1592         unsigned int i;
1593
1594         for (i = 0; i < HFSC_HSIZE; i++) {
1595                 list_for_each_entry(cl, &q->clhash[i], hlist)
1596                         hfsc_reset_class(cl);
1597         }
1598         __skb_queue_purge(&q->requeue);
1599         q->eligible = RB_ROOT;
1600         INIT_LIST_HEAD(&q->droplist);
1601         del_timer(&q->wd_timer);
1602         sch->flags &= ~TCQ_F_THROTTLED;
1603         sch->q.qlen = 0;
1604 }
1605
1606 static void
1607 hfsc_destroy_qdisc(struct Qdisc *sch)
1608 {
1609         struct hfsc_sched *q = qdisc_priv(sch);
1610         struct hfsc_class *cl, *next;
1611         unsigned int i;
1612
1613         for (i = 0; i < HFSC_HSIZE; i++) {
1614                 list_for_each_entry_safe(cl, next, &q->clhash[i], hlist)
1615                         hfsc_destroy_class(sch, cl);
1616         }
1617         __skb_queue_purge(&q->requeue);
1618         del_timer(&q->wd_timer);
1619 }
1620
1621 static int
1622 hfsc_dump_qdisc(struct Qdisc *sch, struct sk_buff *skb)
1623 {
1624         struct hfsc_sched *q = qdisc_priv(sch);
1625         unsigned char *b = skb->tail;
1626         struct tc_hfsc_qopt qopt;
1627
1628         qopt.defcls = q->defcls;
1629         RTA_PUT(skb, TCA_OPTIONS, sizeof(qopt), &qopt);
1630         return skb->len;
1631
1632  rtattr_failure:
1633         skb_trim(skb, b - skb->data);
1634         return -1;
1635 }
1636
1637 static int
1638 hfsc_enqueue(struct sk_buff *skb, struct Qdisc *sch)
1639 {
1640         struct hfsc_class *cl;
1641         unsigned int len;
1642         int err;
1643
1644         cl = hfsc_classify(skb, sch, &err);
1645         if (cl == NULL) {
1646                 if (err == NET_XMIT_BYPASS)
1647                         sch->qstats.drops++;
1648                 kfree_skb(skb);
1649                 return err;
1650         }
1651
1652         len = skb->len;
1653         err = cl->qdisc->enqueue(skb, cl->qdisc);
1654         if (unlikely(err != NET_XMIT_SUCCESS)) {
1655                 cl->qstats.drops++;
1656                 sch->qstats.drops++;
1657                 return err;
1658         }
1659
1660         if (cl->qdisc->q.qlen == 1)
1661                 set_active(cl, len);
1662
1663         cl->bstats.packets++;
1664         cl->bstats.bytes += len;
1665         sch->bstats.packets++;
1666         sch->bstats.bytes += len;
1667         sch->q.qlen++;
1668
1669         return NET_XMIT_SUCCESS;
1670 }
1671
1672 static struct sk_buff *
1673 hfsc_dequeue(struct Qdisc *sch)
1674 {
1675         struct hfsc_sched *q = qdisc_priv(sch);
1676         struct hfsc_class *cl;
1677         struct sk_buff *skb;
1678         u64 cur_time;
1679         unsigned int next_len;
1680         int realtime = 0;
1681
1682         if (sch->q.qlen == 0)
1683                 return NULL;
1684         if ((skb = __skb_dequeue(&q->requeue)))
1685                 goto out;
1686
1687         PSCHED_GET_TIME(cur_time);
1688
1689         /*
1690          * if there are eligible classes, use real-time criteria.
1691          * find the class with the minimum deadline among
1692          * the eligible classes.
1693          */
1694         if ((cl = eltree_get_mindl(q, cur_time)) != NULL) {
1695                 realtime = 1;
1696         } else {
1697                 /*
1698                  * use link-sharing criteria
1699                  * get the class with the minimum vt in the hierarchy
1700                  */
1701                 cl = vttree_get_minvt(&q->root, cur_time);
1702                 if (cl == NULL) {
1703                         sch->qstats.overlimits++;
1704                         hfsc_schedule_watchdog(sch, cur_time);
1705                         return NULL;
1706                 }
1707         }
1708
1709         skb = cl->qdisc->dequeue(cl->qdisc);
1710         if (skb == NULL) {
1711                 if (net_ratelimit())
1712                         printk("HFSC: Non-work-conserving qdisc ?\n");
1713                 return NULL;
1714         }
1715
1716         update_vf(cl, skb->len, cur_time);
1717         if (realtime)
1718                 cl->cl_cumul += skb->len;
1719
1720         if (cl->qdisc->q.qlen != 0) {
1721                 if (cl->cl_flags & HFSC_RSC) {
1722                         /* update ed */
1723                         next_len = qdisc_peek_len(cl->qdisc);
1724                         if (realtime)
1725                                 update_ed(cl, next_len);
1726                         else
1727                                 update_d(cl, next_len);
1728                 }
1729         } else {
1730                 /* the class becomes passive */
1731                 set_passive(cl);
1732         }
1733
1734  out:
1735         sch->flags &= ~TCQ_F_THROTTLED;
1736         sch->q.qlen--;
1737
1738         return skb;
1739 }
1740
1741 static int
1742 hfsc_requeue(struct sk_buff *skb, struct Qdisc *sch)
1743 {
1744         struct hfsc_sched *q = qdisc_priv(sch);
1745
1746         __skb_queue_head(&q->requeue, skb);
1747         sch->q.qlen++;
1748         sch->qstats.requeues++;
1749         return NET_XMIT_SUCCESS;
1750 }
1751
1752 static unsigned int
1753 hfsc_drop(struct Qdisc *sch)
1754 {
1755         struct hfsc_sched *q = qdisc_priv(sch);
1756         struct hfsc_class *cl;
1757         unsigned int len;
1758
1759         list_for_each_entry(cl, &q->droplist, dlist) {
1760                 if (cl->qdisc->ops->drop != NULL &&
1761                     (len = cl->qdisc->ops->drop(cl->qdisc)) > 0) {
1762                         if (cl->qdisc->q.qlen == 0) {
1763                                 update_vf(cl, 0, 0);
1764                                 set_passive(cl);
1765                         } else {
1766                                 list_move_tail(&cl->dlist, &q->droplist);
1767                         }
1768                         cl->qstats.drops++;
1769                         sch->qstats.drops++;
1770                         sch->q.qlen--;
1771                         return len;
1772                 }
1773         }
1774         return 0;
1775 }
1776
1777 static struct Qdisc_class_ops hfsc_class_ops = {
1778         .change         = hfsc_change_class,
1779         .delete         = hfsc_delete_class,
1780         .graft          = hfsc_graft_class,
1781         .leaf           = hfsc_class_leaf,
1782         .get            = hfsc_get_class,
1783         .put            = hfsc_put_class,
1784         .bind_tcf       = hfsc_bind_tcf,
1785         .unbind_tcf     = hfsc_unbind_tcf,
1786         .tcf_chain      = hfsc_tcf_chain,
1787         .dump           = hfsc_dump_class,
1788         .dump_stats     = hfsc_dump_class_stats,
1789         .walk           = hfsc_walk
1790 };
1791
1792 static struct Qdisc_ops hfsc_qdisc_ops = {
1793         .id             = "hfsc",
1794         .init           = hfsc_init_qdisc,
1795         .change         = hfsc_change_qdisc,
1796         .reset          = hfsc_reset_qdisc,
1797         .destroy        = hfsc_destroy_qdisc,
1798         .dump           = hfsc_dump_qdisc,
1799         .enqueue        = hfsc_enqueue,
1800         .dequeue        = hfsc_dequeue,
1801         .requeue        = hfsc_requeue,
1802         .drop           = hfsc_drop,
1803         .cl_ops         = &hfsc_class_ops,
1804         .priv_size      = sizeof(struct hfsc_sched),
1805         .owner          = THIS_MODULE
1806 };
1807
1808 static int __init
1809 hfsc_init(void)
1810 {
1811         return register_qdisc(&hfsc_qdisc_ops);
1812 }
1813
1814 static void __exit
1815 hfsc_cleanup(void)
1816 {
1817         unregister_qdisc(&hfsc_qdisc_ops);
1818 }
1819
1820 MODULE_LICENSE("GPL");
1821 module_init(hfsc_init);
1822 module_exit(hfsc_cleanup);