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