PCI: Add support for AGP in cur/max bus speed
[wandboard.git] / net / sched / sch_prio.c
blob93285cecb246942b5640809d34e7d17d9ee1d63a
1 /*
2 * net/sched/sch_prio.c Simple 3-band priority "scheduler".
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.
9 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
10 * Fixes: 19990609: J Hadi Salim <hadi@nortelnetworks.com>:
11 * Init -- EINVAL when opt undefined
14 #include <linux/module.h>
15 #include <linux/types.h>
16 #include <linux/kernel.h>
17 #include <linux/string.h>
18 #include <linux/errno.h>
19 #include <linux/skbuff.h>
20 #include <net/netlink.h>
21 #include <net/pkt_sched.h>
24 struct prio_sched_data
26 int bands;
27 struct tcf_proto *filter_list;
28 u8 prio2band[TC_PRIO_MAX+1];
29 struct Qdisc *queues[TCQ_PRIO_BANDS];
33 static struct Qdisc *
34 prio_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
36 struct prio_sched_data *q = qdisc_priv(sch);
37 u32 band = skb->priority;
38 struct tcf_result res;
39 int err;
41 *qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
42 if (TC_H_MAJ(skb->priority) != sch->handle) {
43 err = tc_classify(skb, q->filter_list, &res);
44 #ifdef CONFIG_NET_CLS_ACT
45 switch (err) {
46 case TC_ACT_STOLEN:
47 case TC_ACT_QUEUED:
48 *qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
49 case TC_ACT_SHOT:
50 return NULL;
52 #endif
53 if (!q->filter_list || err < 0) {
54 if (TC_H_MAJ(band))
55 band = 0;
56 return q->queues[q->prio2band[band&TC_PRIO_MAX]];
58 band = res.classid;
60 band = TC_H_MIN(band) - 1;
61 if (band >= q->bands)
62 return q->queues[q->prio2band[0]];
64 return q->queues[band];
67 static int
68 prio_enqueue(struct sk_buff *skb, struct Qdisc *sch)
70 struct Qdisc *qdisc;
71 int ret;
73 qdisc = prio_classify(skb, sch, &ret);
74 #ifdef CONFIG_NET_CLS_ACT
75 if (qdisc == NULL) {
77 if (ret & __NET_XMIT_BYPASS)
78 sch->qstats.drops++;
79 kfree_skb(skb);
80 return ret;
82 #endif
84 ret = qdisc_enqueue(skb, qdisc);
85 if (ret == NET_XMIT_SUCCESS) {
86 sch->bstats.bytes += qdisc_pkt_len(skb);
87 sch->bstats.packets++;
88 sch->q.qlen++;
89 return NET_XMIT_SUCCESS;
91 if (net_xmit_drop_count(ret))
92 sch->qstats.drops++;
93 return ret;
96 static struct sk_buff *prio_peek(struct Qdisc *sch)
98 struct prio_sched_data *q = qdisc_priv(sch);
99 int prio;
101 for (prio = 0; prio < q->bands; prio++) {
102 struct Qdisc *qdisc = q->queues[prio];
103 struct sk_buff *skb = qdisc->ops->peek(qdisc);
104 if (skb)
105 return skb;
107 return NULL;
110 static struct sk_buff *prio_dequeue(struct Qdisc* sch)
112 struct prio_sched_data *q = qdisc_priv(sch);
113 int prio;
115 for (prio = 0; prio < q->bands; prio++) {
116 struct Qdisc *qdisc = q->queues[prio];
117 struct sk_buff *skb = qdisc->dequeue(qdisc);
118 if (skb) {
119 sch->q.qlen--;
120 return skb;
123 return NULL;
127 static unsigned int prio_drop(struct Qdisc* sch)
129 struct prio_sched_data *q = qdisc_priv(sch);
130 int prio;
131 unsigned int len;
132 struct Qdisc *qdisc;
134 for (prio = q->bands-1; prio >= 0; prio--) {
135 qdisc = q->queues[prio];
136 if (qdisc->ops->drop && (len = qdisc->ops->drop(qdisc)) != 0) {
137 sch->q.qlen--;
138 return len;
141 return 0;
145 static void
146 prio_reset(struct Qdisc* sch)
148 int prio;
149 struct prio_sched_data *q = qdisc_priv(sch);
151 for (prio=0; prio<q->bands; prio++)
152 qdisc_reset(q->queues[prio]);
153 sch->q.qlen = 0;
156 static void
157 prio_destroy(struct Qdisc* sch)
159 int prio;
160 struct prio_sched_data *q = qdisc_priv(sch);
162 tcf_destroy_chain(&q->filter_list);
163 for (prio=0; prio<q->bands; prio++)
164 qdisc_destroy(q->queues[prio]);
167 static int prio_tune(struct Qdisc *sch, struct nlattr *opt)
169 struct prio_sched_data *q = qdisc_priv(sch);
170 struct tc_prio_qopt *qopt;
171 int i;
173 if (nla_len(opt) < sizeof(*qopt))
174 return -EINVAL;
175 qopt = nla_data(opt);
177 if (qopt->bands > TCQ_PRIO_BANDS || qopt->bands < 2)
178 return -EINVAL;
180 for (i=0; i<=TC_PRIO_MAX; i++) {
181 if (qopt->priomap[i] >= qopt->bands)
182 return -EINVAL;
185 sch_tree_lock(sch);
186 q->bands = qopt->bands;
187 memcpy(q->prio2band, qopt->priomap, TC_PRIO_MAX+1);
189 for (i=q->bands; i<TCQ_PRIO_BANDS; i++) {
190 struct Qdisc *child = q->queues[i];
191 q->queues[i] = &noop_qdisc;
192 if (child != &noop_qdisc) {
193 qdisc_tree_decrease_qlen(child, child->q.qlen);
194 qdisc_destroy(child);
197 sch_tree_unlock(sch);
199 for (i=0; i<q->bands; i++) {
200 if (q->queues[i] == &noop_qdisc) {
201 struct Qdisc *child, *old;
202 child = qdisc_create_dflt(qdisc_dev(sch), sch->dev_queue,
203 &pfifo_qdisc_ops,
204 TC_H_MAKE(sch->handle, i + 1));
205 if (child) {
206 sch_tree_lock(sch);
207 old = q->queues[i];
208 q->queues[i] = child;
210 if (old != &noop_qdisc) {
211 qdisc_tree_decrease_qlen(old,
212 old->q.qlen);
213 qdisc_destroy(old);
215 sch_tree_unlock(sch);
219 return 0;
222 static int prio_init(struct Qdisc *sch, struct nlattr *opt)
224 struct prio_sched_data *q = qdisc_priv(sch);
225 int i;
227 for (i=0; i<TCQ_PRIO_BANDS; i++)
228 q->queues[i] = &noop_qdisc;
230 if (opt == NULL) {
231 return -EINVAL;
232 } else {
233 int err;
235 if ((err= prio_tune(sch, opt)) != 0)
236 return err;
238 return 0;
241 static int prio_dump(struct Qdisc *sch, struct sk_buff *skb)
243 struct prio_sched_data *q = qdisc_priv(sch);
244 unsigned char *b = skb_tail_pointer(skb);
245 struct tc_prio_qopt opt;
247 opt.bands = q->bands;
248 memcpy(&opt.priomap, q->prio2band, TC_PRIO_MAX+1);
250 NLA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt);
252 return skb->len;
254 nla_put_failure:
255 nlmsg_trim(skb, b);
256 return -1;
259 static int prio_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
260 struct Qdisc **old)
262 struct prio_sched_data *q = qdisc_priv(sch);
263 unsigned long band = arg - 1;
265 if (new == NULL)
266 new = &noop_qdisc;
268 sch_tree_lock(sch);
269 *old = q->queues[band];
270 q->queues[band] = new;
271 qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
272 qdisc_reset(*old);
273 sch_tree_unlock(sch);
275 return 0;
278 static struct Qdisc *
279 prio_leaf(struct Qdisc *sch, unsigned long arg)
281 struct prio_sched_data *q = qdisc_priv(sch);
282 unsigned long band = arg - 1;
284 return q->queues[band];
287 static unsigned long prio_get(struct Qdisc *sch, u32 classid)
289 struct prio_sched_data *q = qdisc_priv(sch);
290 unsigned long band = TC_H_MIN(classid);
292 if (band - 1 >= q->bands)
293 return 0;
294 return band;
297 static unsigned long prio_bind(struct Qdisc *sch, unsigned long parent, u32 classid)
299 return prio_get(sch, classid);
303 static void prio_put(struct Qdisc *q, unsigned long cl)
305 return;
308 static int prio_dump_class(struct Qdisc *sch, unsigned long cl, struct sk_buff *skb,
309 struct tcmsg *tcm)
311 struct prio_sched_data *q = qdisc_priv(sch);
313 tcm->tcm_handle |= TC_H_MIN(cl);
314 tcm->tcm_info = q->queues[cl-1]->handle;
315 return 0;
318 static int prio_dump_class_stats(struct Qdisc *sch, unsigned long cl,
319 struct gnet_dump *d)
321 struct prio_sched_data *q = qdisc_priv(sch);
322 struct Qdisc *cl_q;
324 cl_q = q->queues[cl - 1];
325 cl_q->qstats.qlen = cl_q->q.qlen;
326 if (gnet_stats_copy_basic(d, &cl_q->bstats) < 0 ||
327 gnet_stats_copy_queue(d, &cl_q->qstats) < 0)
328 return -1;
330 return 0;
333 static void prio_walk(struct Qdisc *sch, struct qdisc_walker *arg)
335 struct prio_sched_data *q = qdisc_priv(sch);
336 int prio;
338 if (arg->stop)
339 return;
341 for (prio = 0; prio < q->bands; prio++) {
342 if (arg->count < arg->skip) {
343 arg->count++;
344 continue;
346 if (arg->fn(sch, prio+1, arg) < 0) {
347 arg->stop = 1;
348 break;
350 arg->count++;
354 static struct tcf_proto ** prio_find_tcf(struct Qdisc *sch, unsigned long cl)
356 struct prio_sched_data *q = qdisc_priv(sch);
358 if (cl)
359 return NULL;
360 return &q->filter_list;
363 static const struct Qdisc_class_ops prio_class_ops = {
364 .graft = prio_graft,
365 .leaf = prio_leaf,
366 .get = prio_get,
367 .put = prio_put,
368 .walk = prio_walk,
369 .tcf_chain = prio_find_tcf,
370 .bind_tcf = prio_bind,
371 .unbind_tcf = prio_put,
372 .dump = prio_dump_class,
373 .dump_stats = prio_dump_class_stats,
376 static struct Qdisc_ops prio_qdisc_ops __read_mostly = {
377 .next = NULL,
378 .cl_ops = &prio_class_ops,
379 .id = "prio",
380 .priv_size = sizeof(struct prio_sched_data),
381 .enqueue = prio_enqueue,
382 .dequeue = prio_dequeue,
383 .peek = prio_peek,
384 .drop = prio_drop,
385 .init = prio_init,
386 .reset = prio_reset,
387 .destroy = prio_destroy,
388 .change = prio_tune,
389 .dump = prio_dump,
390 .owner = THIS_MODULE,
393 static int __init prio_module_init(void)
395 return register_qdisc(&prio_qdisc_ops);
398 static void __exit prio_module_exit(void)
400 unregister_qdisc(&prio_qdisc_ops);
403 module_init(prio_module_init)
404 module_exit(prio_module_exit)
406 MODULE_LICENSE("GPL");