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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>
22
23
24struct prio_sched_data
25{
26 int bands;
27 struct tcf_proto *filter_list;
28 u8 prio2band[TC_PRIO_MAX+1];
29 struct Qdisc *queues[TCQ_PRIO_BANDS];
30};
31
32
33static struct Qdisc *
34prio_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
35{
36 struct prio_sched_data *q = qdisc_priv(sch);
37 u32 band = skb->priority;
38 struct tcf_result res;
39 int err;
40
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;
51 }
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]];
57 }
58 band = res.classid;
59 }
60 band = TC_H_MIN(band) - 1;
61 if (band >= q->bands)
62 return q->queues[q->prio2band[0]];
63
64 return q->queues[band];
65}
66
67static int
68prio_enqueue(struct sk_buff *skb, struct Qdisc *sch)
69{
70 struct Qdisc *qdisc;
71 int ret;
72
73 qdisc = prio_classify(skb, sch, &ret);
74#ifdef CONFIG_NET_CLS_ACT
75 if (qdisc == NULL) {
76
77 if (ret & __NET_XMIT_BYPASS)
78 sch->qstats.drops++;
79 kfree_skb(skb);
80 return ret;
81 }
82#endif
83
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;
90 }
91 if (net_xmit_drop_count(ret))
92 sch->qstats.drops++;
93 return ret;
94}
95
96static struct sk_buff *prio_peek(struct Qdisc *sch)
97{
98 struct prio_sched_data *q = qdisc_priv(sch);
99 int prio;
100
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;
106 }
107 return NULL;
108}
109
110static struct sk_buff *prio_dequeue(struct Qdisc* sch)
111{
112 struct prio_sched_data *q = qdisc_priv(sch);
113 int prio;
114
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;
121 }
122 }
123 return NULL;
124
125}
126
127static unsigned int prio_drop(struct Qdisc* sch)
128{
129 struct prio_sched_data *q = qdisc_priv(sch);
130 int prio;
131 unsigned int len;
132 struct Qdisc *qdisc;
133
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;
139 }
140 }
141 return 0;
142}
143
144
145static void
146prio_reset(struct Qdisc* sch)
147{
148 int prio;
149 struct prio_sched_data *q = qdisc_priv(sch);
150
151 for (prio=0; prio<q->bands; prio++)
152 qdisc_reset(q->queues[prio]);
153 sch->q.qlen = 0;
154}
155
156static void
157prio_destroy(struct Qdisc* sch)
158{
159 int prio;
160 struct prio_sched_data *q = qdisc_priv(sch);
161
162 tcf_destroy_chain(&q->filter_list);
163 for (prio=0; prio<q->bands; prio++)
164 qdisc_destroy(q->queues[prio]);
165}
166
167static int prio_tune(struct Qdisc *sch, struct nlattr *opt)
168{
169 struct prio_sched_data *q = qdisc_priv(sch);
170 struct tc_prio_qopt *qopt;
171 int i;
172
173 if (nla_len(opt) < sizeof(*qopt))
174 return -EINVAL;
175 qopt = nla_data(opt);
176
177 if (qopt->bands > TCQ_PRIO_BANDS || qopt->bands < 2)
178 return -EINVAL;
179
180 for (i=0; i<=TC_PRIO_MAX; i++) {
181 if (qopt->priomap[i] >= qopt->bands)
182 return -EINVAL;
183 }
184
185 sch_tree_lock(sch);
186 q->bands = qopt->bands;
187 memcpy(q->prio2band, qopt->priomap, TC_PRIO_MAX+1);
188
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);
195 }
196 }
197 sch_tree_unlock(sch);
198
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;
209
210 if (old != &noop_qdisc) {
211 qdisc_tree_decrease_qlen(old,
212 old->q.qlen);
213 qdisc_destroy(old);
214 }
215 sch_tree_unlock(sch);
216 }
217 }
218 }
219 return 0;
220}
221
222static int prio_init(struct Qdisc *sch, struct nlattr *opt)
223{
224 struct prio_sched_data *q = qdisc_priv(sch);
225 int i;
226
227 for (i=0; i<TCQ_PRIO_BANDS; i++)
228 q->queues[i] = &noop_qdisc;
229
230 if (opt == NULL) {
231 return -EINVAL;
232 } else {
233 int err;
234
235 if ((err= prio_tune(sch, opt)) != 0)
236 return err;
237 }
238 return 0;
239}
240
241static int prio_dump(struct Qdisc *sch, struct sk_buff *skb)
242{
243 struct prio_sched_data *q = qdisc_priv(sch);
244 unsigned char *b = skb_tail_pointer(skb);
245 struct tc_prio_qopt opt;
246
247 opt.bands = q->bands;
248 memcpy(&opt.priomap, q->prio2band, TC_PRIO_MAX+1);
249
250 NLA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt);
251
252 return skb->len;
253
254nla_put_failure:
255 nlmsg_trim(skb, b);
256 return -1;
257}
258
259static int prio_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
260 struct Qdisc **old)
261{
262 struct prio_sched_data *q = qdisc_priv(sch);
263 unsigned long band = arg - 1;
264
265 if (new == NULL)
266 new = &noop_qdisc;
267
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);
274
275 return 0;
276}
277
278static struct Qdisc *
279prio_leaf(struct Qdisc *sch, unsigned long arg)
280{
281 struct prio_sched_data *q = qdisc_priv(sch);
282 unsigned long band = arg - 1;
283
284 return q->queues[band];
285}
286
287static unsigned long prio_get(struct Qdisc *sch, u32 classid)
288{
289 struct prio_sched_data *q = qdisc_priv(sch);
290 unsigned long band = TC_H_MIN(classid);
291
292 if (band - 1 >= q->bands)
293 return 0;
294 return band;
295}
296
297static unsigned long prio_bind(struct Qdisc *sch, unsigned long parent, u32 classid)
298{
299 return prio_get(sch, classid);
300}
301
302
303static void prio_put(struct Qdisc *q, unsigned long cl)
304{
305 return;
306}
307
308static int prio_dump_class(struct Qdisc *sch, unsigned long cl, struct sk_buff *skb,
309 struct tcmsg *tcm)
310{
311 struct prio_sched_data *q = qdisc_priv(sch);
312
313 tcm->tcm_handle |= TC_H_MIN(cl);
314 tcm->tcm_info = q->queues[cl-1]->handle;
315 return 0;
316}
317
318static int prio_dump_class_stats(struct Qdisc *sch, unsigned long cl,
319 struct gnet_dump *d)
320{
321 struct prio_sched_data *q = qdisc_priv(sch);
322 struct Qdisc *cl_q;
323
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;
329
330 return 0;
331}
332
333static void prio_walk(struct Qdisc *sch, struct qdisc_walker *arg)
334{
335 struct prio_sched_data *q = qdisc_priv(sch);
336 int prio;
337
338 if (arg->stop)
339 return;
340
341 for (prio = 0; prio < q->bands; prio++) {
342 if (arg->count < arg->skip) {
343 arg->count++;
344 continue;
345 }
346 if (arg->fn(sch, prio+1, arg) < 0) {
347 arg->stop = 1;
348 break;
349 }
350 arg->count++;
351 }
352}
353
354static struct tcf_proto ** prio_find_tcf(struct Qdisc *sch, unsigned long cl)
355{
356 struct prio_sched_data *q = qdisc_priv(sch);
357
358 if (cl)
359 return NULL;
360 return &q->filter_list;
361}
362
363static 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,
374};
375
376static 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,
391};
392
393static int __init prio_module_init(void)
394{
395 return register_qdisc(&prio_qdisc_ops);
396}
397
398static void __exit prio_module_exit(void)
399{
400 unregister_qdisc(&prio_qdisc_ops);
401}
402
403module_init(prio_module_init)
404module_exit(prio_module_exit)
405
406MODULE_LICENSE("GPL");
407
