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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
96
97static int
98prio_requeue(struct sk_buff *skb, struct Qdisc* sch)
99{
100 struct Qdisc *qdisc;
101 int ret;
102
103 qdisc = prio_classify(skb, sch, &ret);
104#ifdef CONFIG_NET_CLS_ACT
105 if (qdisc == NULL) {
106 if (ret & __NET_XMIT_BYPASS)
107 sch->qstats.drops++;
108 kfree_skb(skb);
109 return ret;
110 }
111#endif
112
113 if ((ret = qdisc->ops->requeue(skb, qdisc)) == NET_XMIT_SUCCESS) {
114 sch->q.qlen++;
115 sch->qstats.requeues++;
116 return NET_XMIT_SUCCESS;
117 }
118 if (net_xmit_drop_count(ret))
119 sch->qstats.drops++;
120 return ret;
121}
122
123
124static struct sk_buff *prio_dequeue(struct Qdisc* sch)
125{
126 struct prio_sched_data *q = qdisc_priv(sch);
127 int prio;
128
129 for (prio = 0; prio < q->bands; prio++) {
130 struct Qdisc *qdisc = q->queues[prio];
131 struct sk_buff *skb = qdisc->dequeue(qdisc);
132 if (skb) {
133 sch->q.qlen--;
134 return skb;
135 }
136 }
137 return NULL;
138
139}
140
141static unsigned int prio_drop(struct Qdisc* sch)
142{
143 struct prio_sched_data *q = qdisc_priv(sch);
144 int prio;
145 unsigned int len;
146 struct Qdisc *qdisc;
147
148 for (prio = q->bands-1; prio >= 0; prio--) {
149 qdisc = q->queues[prio];
150 if (qdisc->ops->drop && (len = qdisc->ops->drop(qdisc)) != 0) {
151 sch->q.qlen--;
152 return len;
153 }
154 }
155 return 0;
156}
157
158
159static void
160prio_reset(struct Qdisc* sch)
161{
162 int prio;
163 struct prio_sched_data *q = qdisc_priv(sch);
164
165 for (prio=0; prio<q->bands; prio++)
166 qdisc_reset(q->queues[prio]);
167 sch->q.qlen = 0;
168}
169
170static void
171prio_destroy(struct Qdisc* sch)
172{
173 int prio;
174 struct prio_sched_data *q = qdisc_priv(sch);
175
176 tcf_destroy_chain(&q->filter_list);
177 for (prio=0; prio<q->bands; prio++)
178 qdisc_destroy(q->queues[prio]);
179}
180
181static int prio_tune(struct Qdisc *sch, struct nlattr *opt)
182{
183 struct prio_sched_data *q = qdisc_priv(sch);
184 struct tc_prio_qopt *qopt;
185 int i;
186
187 if (nla_len(opt) < sizeof(*qopt))
188 return -EINVAL;
189 qopt = nla_data(opt);
190
191 if (qopt->bands > TCQ_PRIO_BANDS || qopt->bands < 2)
192 return -EINVAL;
193
194 for (i=0; i<=TC_PRIO_MAX; i++) {
195 if (qopt->priomap[i] >= qopt->bands)
196 return -EINVAL;
197 }
198
199 sch_tree_lock(sch);
200 q->bands = qopt->bands;
201 memcpy(q->prio2band, qopt->priomap, TC_PRIO_MAX+1);
202
203 for (i=q->bands; i<TCQ_PRIO_BANDS; i++) {
204 struct Qdisc *child = xchg(&q->queues[i], &noop_qdisc);
205 if (child != &noop_qdisc) {
206 qdisc_tree_decrease_qlen(child, child->q.qlen);
207 qdisc_destroy(child);
208 }
209 }
210 sch_tree_unlock(sch);
211
212 for (i=0; i<q->bands; i++) {
213 if (q->queues[i] == &noop_qdisc) {
214 struct Qdisc *child;
215 child = qdisc_create_dflt(qdisc_dev(sch), sch->dev_queue,
216 &pfifo_qdisc_ops,
217 TC_H_MAKE(sch->handle, i + 1));
218 if (child) {
219 sch_tree_lock(sch);
220 child = xchg(&q->queues[i], child);
221
222 if (child != &noop_qdisc) {
223 qdisc_tree_decrease_qlen(child,
224 child->q.qlen);
225 qdisc_destroy(child);
226 }
227 sch_tree_unlock(sch);
228 }
229 }
230 }
231 return 0;
232}
233
234static int prio_init(struct Qdisc *sch, struct nlattr *opt)
235{
236 struct prio_sched_data *q = qdisc_priv(sch);
237 int i;
238
239 for (i=0; i<TCQ_PRIO_BANDS; i++)
240 q->queues[i] = &noop_qdisc;
241
242 if (opt == NULL) {
243 return -EINVAL;
244 } else {
245 int err;
246
247 if ((err= prio_tune(sch, opt)) != 0)
248 return err;
249 }
250 return 0;
251}
252
253static int prio_dump(struct Qdisc *sch, struct sk_buff *skb)
254{
255 struct prio_sched_data *q = qdisc_priv(sch);
256 unsigned char *b = skb_tail_pointer(skb);
257 struct tc_prio_qopt opt;
258
259 opt.bands = q->bands;
260 memcpy(&opt.priomap, q->prio2band, TC_PRIO_MAX+1);
261
262 NLA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt);
263
264 return skb->len;
265
266nla_put_failure:
267 nlmsg_trim(skb, b);
268 return -1;
269}
270
271static int prio_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
272 struct Qdisc **old)
273{
274 struct prio_sched_data *q = qdisc_priv(sch);
275 unsigned long band = arg - 1;
276
277 if (band >= q->bands)
278 return -EINVAL;
279
280 if (new == NULL)
281 new = &noop_qdisc;
282
283 sch_tree_lock(sch);
284 *old = q->queues[band];
285 q->queues[band] = new;
286 qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
287 qdisc_reset(*old);
288 sch_tree_unlock(sch);
289
290 return 0;
291}
292
293static struct Qdisc *
294prio_leaf(struct Qdisc *sch, unsigned long arg)
295{
296 struct prio_sched_data *q = qdisc_priv(sch);
297 unsigned long band = arg - 1;
298
299 if (band >= q->bands)
300 return NULL;
301
302 return q->queues[band];
303}
304
305static unsigned long prio_get(struct Qdisc *sch, u32 classid)
306{
307 struct prio_sched_data *q = qdisc_priv(sch);
308 unsigned long band = TC_H_MIN(classid);
309
310 if (band - 1 >= q->bands)
311 return 0;
312 return band;
313}
314
315static unsigned long prio_bind(struct Qdisc *sch, unsigned long parent, u32 classid)
316{
317 return prio_get(sch, classid);
318}
319
320
321static void prio_put(struct Qdisc *q, unsigned long cl)
322{
323 return;
324}
325
326static int prio_change(struct Qdisc *sch, u32 handle, u32 parent, struct nlattr **tca, unsigned long *arg)
327{
328 unsigned long cl = *arg;
329 struct prio_sched_data *q = qdisc_priv(sch);
330
331 if (cl - 1 > q->bands)
332 return -ENOENT;
333 return 0;
334}
335
336static int prio_delete(struct Qdisc *sch, unsigned long cl)
337{
338 struct prio_sched_data *q = qdisc_priv(sch);
339 if (cl - 1 > q->bands)
340 return -ENOENT;
341 return 0;
342}
343
344
345static int prio_dump_class(struct Qdisc *sch, unsigned long cl, struct sk_buff *skb,
346 struct tcmsg *tcm)
347{
348 struct prio_sched_data *q = qdisc_priv(sch);
349
350 if (cl - 1 > q->bands)
351 return -ENOENT;
352 tcm->tcm_handle |= TC_H_MIN(cl);
353 if (q->queues[cl-1])
354 tcm->tcm_info = q->queues[cl-1]->handle;
355 return 0;
356}
357
358static int prio_dump_class_stats(struct Qdisc *sch, unsigned long cl,
359 struct gnet_dump *d)
360{
361 struct prio_sched_data *q = qdisc_priv(sch);
362 struct Qdisc *cl_q;
363
364 cl_q = q->queues[cl - 1];
365 if (gnet_stats_copy_basic(d, &cl_q->bstats) < 0 ||
366 gnet_stats_copy_queue(d, &cl_q->qstats) < 0)
367 return -1;
368
369 return 0;
370}
371
372static void prio_walk(struct Qdisc *sch, struct qdisc_walker *arg)
373{
374 struct prio_sched_data *q = qdisc_priv(sch);
375 int prio;
376
377 if (arg->stop)
378 return;
379
380 for (prio = 0; prio < q->bands; prio++) {
381 if (arg->count < arg->skip) {
382 arg->count++;
383 continue;
384 }
385 if (arg->fn(sch, prio+1, arg) < 0) {
386 arg->stop = 1;
387 break;
388 }
389 arg->count++;
390 }
391}
392
393static struct tcf_proto ** prio_find_tcf(struct Qdisc *sch, unsigned long cl)
394{
395 struct prio_sched_data *q = qdisc_priv(sch);
396
397 if (cl)
398 return NULL;
399 return &q->filter_list;
400}
401
402static const struct Qdisc_class_ops prio_class_ops = {
403 .graft = prio_graft,
404 .leaf = prio_leaf,
405 .get = prio_get,
406 .put = prio_put,
407 .change = prio_change,
408 .delete = prio_delete,
409 .walk = prio_walk,
410 .tcf_chain = prio_find_tcf,
411 .bind_tcf = prio_bind,
412 .unbind_tcf = prio_put,
413 .dump = prio_dump_class,
414 .dump_stats = prio_dump_class_stats,
415};
416
417static struct Qdisc_ops prio_qdisc_ops __read_mostly = {
418 .next = NULL,
419 .cl_ops = &prio_class_ops,
420 .id = "prio",
421 .priv_size = sizeof(struct prio_sched_data),
422 .enqueue = prio_enqueue,
423 .dequeue = prio_dequeue,
424 .requeue = prio_requeue,
425 .drop = prio_drop,
426 .init = prio_init,
427 .reset = prio_reset,
428 .destroy = prio_destroy,
429 .change = prio_tune,
430 .dump = prio_dump,
431 .owner = THIS_MODULE,
432};
433
434static int __init prio_module_init(void)
435{
436 return register_qdisc(&prio_qdisc_ops);
437}
438
439static void __exit prio_module_exit(void)
440{
441 unregister_qdisc(&prio_qdisc_ops);
442}
443
444module_init(prio_module_init)
445module_exit(prio_module_exit)
446
447MODULE_LICENSE("GPL");
448
