Remove obsolete #include <linux/config.h>
[linux-2.6.git] / net / sched / sch_prio.c
1 /*
2  * net/sched/sch_prio.c Simple 3-band priority "scheduler".
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
7  *              2 of the License, or (at your option) any later version.
8  *
9  * Authors:     Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
10  * Fixes:       19990609: J Hadi Salim <hadi@nortelnetworks.com>: 
11  *              Init --  EINVAL when opt undefined
12  */
13
14 #include <linux/module.h>
15 #include <asm/uaccess.h>
16 #include <asm/system.h>
17 #include <linux/bitops.h>
18 #include <linux/types.h>
19 #include <linux/kernel.h>
20 #include <linux/sched.h>
21 #include <linux/string.h>
22 #include <linux/mm.h>
23 #include <linux/socket.h>
24 #include <linux/sockios.h>
25 #include <linux/in.h>
26 #include <linux/errno.h>
27 #include <linux/interrupt.h>
28 #include <linux/if_ether.h>
29 #include <linux/inet.h>
30 #include <linux/netdevice.h>
31 #include <linux/etherdevice.h>
32 #include <linux/notifier.h>
33 #include <net/ip.h>
34 #include <net/route.h>
35 #include <linux/skbuff.h>
36 #include <net/sock.h>
37 #include <net/pkt_sched.h>
38
39
40 struct prio_sched_data
41 {
42         int bands;
43         struct tcf_proto *filter_list;
44         u8  prio2band[TC_PRIO_MAX+1];
45         struct Qdisc *queues[TCQ_PRIO_BANDS];
46 };
47
48
49 static struct Qdisc *
50 prio_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
51 {
52         struct prio_sched_data *q = qdisc_priv(sch);
53         u32 band = skb->priority;
54         struct tcf_result res;
55
56         *qerr = NET_XMIT_BYPASS;
57         if (TC_H_MAJ(skb->priority) != sch->handle) {
58 #ifdef CONFIG_NET_CLS_ACT
59                 switch (tc_classify(skb, q->filter_list, &res)) {
60                 case TC_ACT_STOLEN:
61                 case TC_ACT_QUEUED:
62                         *qerr = NET_XMIT_SUCCESS;
63                 case TC_ACT_SHOT:
64                         return NULL;
65                 };
66
67                 if (!q->filter_list ) {
68 #else
69                 if (!q->filter_list || tc_classify(skb, q->filter_list, &res)) {
70 #endif
71                         if (TC_H_MAJ(band))
72                                 band = 0;
73                         return q->queues[q->prio2band[band&TC_PRIO_MAX]];
74                 }
75                 band = res.classid;
76         }
77         band = TC_H_MIN(band) - 1;
78         if (band > q->bands)
79                 return q->queues[q->prio2band[0]];
80
81         return q->queues[band];
82 }
83
84 static int
85 prio_enqueue(struct sk_buff *skb, struct Qdisc *sch)
86 {
87         struct Qdisc *qdisc;
88         int ret;
89
90         qdisc = prio_classify(skb, sch, &ret);
91 #ifdef CONFIG_NET_CLS_ACT
92         if (qdisc == NULL) {
93
94                 if (ret == NET_XMIT_BYPASS)
95                         sch->qstats.drops++;
96                 kfree_skb(skb);
97                 return ret;
98         }
99 #endif
100
101         if ((ret = qdisc->enqueue(skb, qdisc)) == NET_XMIT_SUCCESS) {
102                 sch->bstats.bytes += skb->len;
103                 sch->bstats.packets++;
104                 sch->q.qlen++;
105                 return NET_XMIT_SUCCESS;
106         }
107         sch->qstats.drops++;
108         return ret; 
109 }
110
111
112 static int
113 prio_requeue(struct sk_buff *skb, struct Qdisc* sch)
114 {
115         struct Qdisc *qdisc;
116         int ret;
117
118         qdisc = prio_classify(skb, sch, &ret);
119 #ifdef CONFIG_NET_CLS_ACT
120         if (qdisc == NULL) {
121                 if (ret == NET_XMIT_BYPASS)
122                         sch->qstats.drops++;
123                 kfree_skb(skb);
124                 return ret;
125         }
126 #endif
127
128         if ((ret = qdisc->ops->requeue(skb, qdisc)) == NET_XMIT_SUCCESS) {
129                 sch->q.qlen++;
130                 sch->qstats.requeues++;
131                 return 0;
132         }
133         sch->qstats.drops++;
134         return NET_XMIT_DROP;
135 }
136
137
138 static struct sk_buff *
139 prio_dequeue(struct Qdisc* sch)
140 {
141         struct sk_buff *skb;
142         struct prio_sched_data *q = qdisc_priv(sch);
143         int prio;
144         struct Qdisc *qdisc;
145
146         for (prio = 0; prio < q->bands; prio++) {
147                 qdisc = q->queues[prio];
148                 skb = qdisc->dequeue(qdisc);
149                 if (skb) {
150                         sch->q.qlen--;
151                         return skb;
152                 }
153         }
154         return NULL;
155
156 }
157
158 static unsigned int prio_drop(struct Qdisc* sch)
159 {
160         struct prio_sched_data *q = qdisc_priv(sch);
161         int prio;
162         unsigned int len;
163         struct Qdisc *qdisc;
164
165         for (prio = q->bands-1; prio >= 0; prio--) {
166                 qdisc = q->queues[prio];
167                 if (qdisc->ops->drop && (len = qdisc->ops->drop(qdisc)) != 0) {
168                         sch->q.qlen--;
169                         return len;
170                 }
171         }
172         return 0;
173 }
174
175
176 static void
177 prio_reset(struct Qdisc* sch)
178 {
179         int prio;
180         struct prio_sched_data *q = qdisc_priv(sch);
181
182         for (prio=0; prio<q->bands; prio++)
183                 qdisc_reset(q->queues[prio]);
184         sch->q.qlen = 0;
185 }
186
187 static void
188 prio_destroy(struct Qdisc* sch)
189 {
190         int prio;
191         struct prio_sched_data *q = qdisc_priv(sch);
192         struct tcf_proto *tp;
193
194         while ((tp = q->filter_list) != NULL) {
195                 q->filter_list = tp->next;
196                 tcf_destroy(tp);
197         }
198
199         for (prio=0; prio<q->bands; prio++)
200                 qdisc_destroy(q->queues[prio]);
201 }
202
203 static int prio_tune(struct Qdisc *sch, struct rtattr *opt)
204 {
205         struct prio_sched_data *q = qdisc_priv(sch);
206         struct tc_prio_qopt *qopt = RTA_DATA(opt);
207         int i;
208
209         if (opt->rta_len < RTA_LENGTH(sizeof(*qopt)))
210                 return -EINVAL;
211         if (qopt->bands > TCQ_PRIO_BANDS || qopt->bands < 2)
212                 return -EINVAL;
213
214         for (i=0; i<=TC_PRIO_MAX; i++) {
215                 if (qopt->priomap[i] >= qopt->bands)
216                         return -EINVAL;
217         }
218
219         sch_tree_lock(sch);
220         q->bands = qopt->bands;
221         memcpy(q->prio2band, qopt->priomap, TC_PRIO_MAX+1);
222
223         for (i=q->bands; i<TCQ_PRIO_BANDS; i++) {
224                 struct Qdisc *child = xchg(&q->queues[i], &noop_qdisc);
225                 if (child != &noop_qdisc)
226                         qdisc_destroy(child);
227         }
228         sch_tree_unlock(sch);
229
230         for (i=0; i<q->bands; i++) {
231                 if (q->queues[i] == &noop_qdisc) {
232                         struct Qdisc *child;
233                         child = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops);
234                         if (child) {
235                                 sch_tree_lock(sch);
236                                 child = xchg(&q->queues[i], child);
237
238                                 if (child != &noop_qdisc)
239                                         qdisc_destroy(child);
240                                 sch_tree_unlock(sch);
241                         }
242                 }
243         }
244         return 0;
245 }
246
247 static int prio_init(struct Qdisc *sch, struct rtattr *opt)
248 {
249         struct prio_sched_data *q = qdisc_priv(sch);
250         int i;
251
252         for (i=0; i<TCQ_PRIO_BANDS; i++)
253                 q->queues[i] = &noop_qdisc;
254
255         if (opt == NULL) {
256                 return -EINVAL;
257         } else {
258                 int err;
259
260                 if ((err= prio_tune(sch, opt)) != 0)
261                         return err;
262         }
263         return 0;
264 }
265
266 static int prio_dump(struct Qdisc *sch, struct sk_buff *skb)
267 {
268         struct prio_sched_data *q = qdisc_priv(sch);
269         unsigned char    *b = skb->tail;
270         struct tc_prio_qopt opt;
271
272         opt.bands = q->bands;
273         memcpy(&opt.priomap, q->prio2band, TC_PRIO_MAX+1);
274         RTA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt);
275         return skb->len;
276
277 rtattr_failure:
278         skb_trim(skb, b - skb->data);
279         return -1;
280 }
281
282 static int prio_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
283                       struct Qdisc **old)
284 {
285         struct prio_sched_data *q = qdisc_priv(sch);
286         unsigned long band = arg - 1;
287
288         if (band >= q->bands)
289                 return -EINVAL;
290
291         if (new == NULL)
292                 new = &noop_qdisc;
293
294         sch_tree_lock(sch);
295         *old = q->queues[band];
296         q->queues[band] = new;
297         sch->q.qlen -= (*old)->q.qlen;
298         qdisc_reset(*old);
299         sch_tree_unlock(sch);
300
301         return 0;
302 }
303
304 static struct Qdisc *
305 prio_leaf(struct Qdisc *sch, unsigned long arg)
306 {
307         struct prio_sched_data *q = qdisc_priv(sch);
308         unsigned long band = arg - 1;
309
310         if (band >= q->bands)
311                 return NULL;
312
313         return q->queues[band];
314 }
315
316 static unsigned long prio_get(struct Qdisc *sch, u32 classid)
317 {
318         struct prio_sched_data *q = qdisc_priv(sch);
319         unsigned long band = TC_H_MIN(classid);
320
321         if (band - 1 >= q->bands)
322                 return 0;
323         return band;
324 }
325
326 static unsigned long prio_bind(struct Qdisc *sch, unsigned long parent, u32 classid)
327 {
328         return prio_get(sch, classid);
329 }
330
331
332 static void prio_put(struct Qdisc *q, unsigned long cl)
333 {
334         return;
335 }
336
337 static int prio_change(struct Qdisc *sch, u32 handle, u32 parent, struct rtattr **tca, unsigned long *arg)
338 {
339         unsigned long cl = *arg;
340         struct prio_sched_data *q = qdisc_priv(sch);
341
342         if (cl - 1 > q->bands)
343                 return -ENOENT;
344         return 0;
345 }
346
347 static int prio_delete(struct Qdisc *sch, unsigned long cl)
348 {
349         struct prio_sched_data *q = qdisc_priv(sch);
350         if (cl - 1 > q->bands)
351                 return -ENOENT;
352         return 0;
353 }
354
355
356 static int prio_dump_class(struct Qdisc *sch, unsigned long cl, struct sk_buff *skb,
357                            struct tcmsg *tcm)
358 {
359         struct prio_sched_data *q = qdisc_priv(sch);
360
361         if (cl - 1 > q->bands)
362                 return -ENOENT;
363         tcm->tcm_handle |= TC_H_MIN(cl);
364         if (q->queues[cl-1])
365                 tcm->tcm_info = q->queues[cl-1]->handle;
366         return 0;
367 }
368
369 static void prio_walk(struct Qdisc *sch, struct qdisc_walker *arg)
370 {
371         struct prio_sched_data *q = qdisc_priv(sch);
372         int prio;
373
374         if (arg->stop)
375                 return;
376
377         for (prio = 0; prio < q->bands; prio++) {
378                 if (arg->count < arg->skip) {
379                         arg->count++;
380                         continue;
381                 }
382                 if (arg->fn(sch, prio+1, arg) < 0) {
383                         arg->stop = 1;
384                         break;
385                 }
386                 arg->count++;
387         }
388 }
389
390 static struct tcf_proto ** prio_find_tcf(struct Qdisc *sch, unsigned long cl)
391 {
392         struct prio_sched_data *q = qdisc_priv(sch);
393
394         if (cl)
395                 return NULL;
396         return &q->filter_list;
397 }
398
399 static struct Qdisc_class_ops prio_class_ops = {
400         .graft          =       prio_graft,
401         .leaf           =       prio_leaf,
402         .get            =       prio_get,
403         .put            =       prio_put,
404         .change         =       prio_change,
405         .delete         =       prio_delete,
406         .walk           =       prio_walk,
407         .tcf_chain      =       prio_find_tcf,
408         .bind_tcf       =       prio_bind,
409         .unbind_tcf     =       prio_put,
410         .dump           =       prio_dump_class,
411 };
412
413 static struct Qdisc_ops prio_qdisc_ops = {
414         .next           =       NULL,
415         .cl_ops         =       &prio_class_ops,
416         .id             =       "prio",
417         .priv_size      =       sizeof(struct prio_sched_data),
418         .enqueue        =       prio_enqueue,
419         .dequeue        =       prio_dequeue,
420         .requeue        =       prio_requeue,
421         .drop           =       prio_drop,
422         .init           =       prio_init,
423         .reset          =       prio_reset,
424         .destroy        =       prio_destroy,
425         .change         =       prio_tune,
426         .dump           =       prio_dump,
427         .owner          =       THIS_MODULE,
428 };
429
430 static int __init prio_module_init(void)
431 {
432         return register_qdisc(&prio_qdisc_ops);
433 }
434
435 static void __exit prio_module_exit(void) 
436 {
437         unregister_qdisc(&prio_qdisc_ops);
438 }
439
440 module_init(prio_module_init)
441 module_exit(prio_module_exit)
442
443 MODULE_LICENSE("GPL");