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14#include <linux/module.h>
15#include <linux/slab.h>
16#include <linux/types.h>
17#include <linux/kernel.h>
18#include <linux/string.h>
19#include <linux/errno.h>
20#include <linux/skbuff.h>
21#include <net/netlink.h>
22#include <net/pkt_sched.h>
23
24
25struct prio_sched_data
26{
27 int bands;
28 struct tcf_proto *filter_list;
29 u8 prio2band[TC_PRIO_MAX+1];
30 struct Qdisc *queues[TCQ_PRIO_BANDS];
31};
32
33
34static struct Qdisc *
35prio_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
36{
37 struct prio_sched_data *q = qdisc_priv(sch);
38 u32 band = skb->priority;
39 struct tcf_result res;
40 int err;
41
42 *qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
43 if (TC_H_MAJ(skb->priority) != sch->handle) {
44 err = tc_classify(skb, q->filter_list, &res);
45#ifdef CONFIG_NET_CLS_ACT
46 switch (err) {
47 case TC_ACT_STOLEN:
48 case TC_ACT_QUEUED:
49 *qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
50 case TC_ACT_SHOT:
51 return NULL;
52 }
53#endif
54 if (!q->filter_list || err < 0) {
55 if (TC_H_MAJ(band))
56 band = 0;
57 return q->queues[q->prio2band[band&TC_PRIO_MAX]];
58 }
59 band = res.classid;
60 }
61 band = TC_H_MIN(band) - 1;
62 if (band >= q->bands)
63 return q->queues[q->prio2band[0]];
64
65 return q->queues[band];
66}
67
68static int
69prio_enqueue(struct sk_buff *skb, struct Qdisc *sch)
70{
71 struct Qdisc *qdisc;
72 int ret;
73
74 qdisc = prio_classify(skb, sch, &ret);
75#ifdef CONFIG_NET_CLS_ACT
76 if (qdisc == NULL) {
77
78 if (ret & __NET_XMIT_BYPASS)
79 sch->qstats.drops++;
80 kfree_skb(skb);
81 return ret;
82 }
83#endif
84
85 ret = qdisc_enqueue(skb, qdisc);
86 if (ret == NET_XMIT_SUCCESS) {
87 sch->bstats.bytes += qdisc_pkt_len(skb);
88 sch->bstats.packets++;
89 sch->q.qlen++;
90 return NET_XMIT_SUCCESS;
91 }
92 if (net_xmit_drop_count(ret))
93 sch->qstats.drops++;
94 return ret;
95}
96
97static struct sk_buff *prio_peek(struct Qdisc *sch)
98{
99 struct prio_sched_data *q = qdisc_priv(sch);
100 int prio;
101
102 for (prio = 0; prio < q->bands; prio++) {
103 struct Qdisc *qdisc = q->queues[prio];
104 struct sk_buff *skb = qdisc->ops->peek(qdisc);
105 if (skb)
106 return skb;
107 }
108 return NULL;
109}
110
111static struct sk_buff *prio_dequeue(struct Qdisc* sch)
112{
113 struct prio_sched_data *q = qdisc_priv(sch);
114 int prio;
115
116 for (prio = 0; prio < q->bands; prio++) {
117 struct Qdisc *qdisc = q->queues[prio];
118 struct sk_buff *skb = qdisc->dequeue(qdisc);
119 if (skb) {
120 sch->q.qlen--;
121 return skb;
122 }
123 }
124 return NULL;
125
126}
127
128static unsigned int prio_drop(struct Qdisc* sch)
129{
130 struct prio_sched_data *q = qdisc_priv(sch);
131 int prio;
132 unsigned int len;
133 struct Qdisc *qdisc;
134
135 for (prio = q->bands-1; prio >= 0; prio--) {
136 qdisc = q->queues[prio];
137 if (qdisc->ops->drop && (len = qdisc->ops->drop(qdisc)) != 0) {
138 sch->q.qlen--;
139 return len;
140 }
141 }
142 return 0;
143}
144
145
146static void
147prio_reset(struct Qdisc* sch)
148{
149 int prio;
150 struct prio_sched_data *q = qdisc_priv(sch);
151
152 for (prio=0; prio<q->bands; prio++)
153 qdisc_reset(q->queues[prio]);
154 sch->q.qlen = 0;
155}
156
157static void
158prio_destroy(struct Qdisc* sch)
159{
160 int prio;
161 struct prio_sched_data *q = qdisc_priv(sch);
162
163 tcf_destroy_chain(&q->filter_list);
164 for (prio=0; prio<q->bands; prio++)
165 qdisc_destroy(q->queues[prio]);
166}
167
168static int prio_tune(struct Qdisc *sch, struct nlattr *opt)
169{
170 struct prio_sched_data *q = qdisc_priv(sch);
171 struct tc_prio_qopt *qopt;
172 int i;
173
174 if (nla_len(opt) < sizeof(*qopt))
175 return -EINVAL;
176 qopt = nla_data(opt);
177
178 if (qopt->bands > TCQ_PRIO_BANDS || qopt->bands < 2)
179 return -EINVAL;
180
181 for (i=0; i<=TC_PRIO_MAX; i++) {
182 if (qopt->priomap[i] >= qopt->bands)
183 return -EINVAL;
184 }
185
186 sch_tree_lock(sch);
187 q->bands = qopt->bands;
188 memcpy(q->prio2band, qopt->priomap, TC_PRIO_MAX+1);
189
190 for (i=q->bands; i<TCQ_PRIO_BANDS; i++) {
191 struct Qdisc *child = q->queues[i];
192 q->queues[i] = &noop_qdisc;
193 if (child != &noop_qdisc) {
194 qdisc_tree_decrease_qlen(child, child->q.qlen);
195 qdisc_destroy(child);
196 }
197 }
198 sch_tree_unlock(sch);
199
200 for (i=0; i<q->bands; i++) {
201 if (q->queues[i] == &noop_qdisc) {
202 struct Qdisc *child, *old;
203 child = qdisc_create_dflt(qdisc_dev(sch), sch->dev_queue,
204 &pfifo_qdisc_ops,
205 TC_H_MAKE(sch->handle, i + 1));
206 if (child) {
207 sch_tree_lock(sch);
208 old = q->queues[i];
209 q->queues[i] = child;
210
211 if (old != &noop_qdisc) {
212 qdisc_tree_decrease_qlen(old,
213 old->q.qlen);
214 qdisc_destroy(old);
215 }
216 sch_tree_unlock(sch);
217 }
218 }
219 }
220 return 0;
221}
222
223static int prio_init(struct Qdisc *sch, struct nlattr *opt)
224{
225 struct prio_sched_data *q = qdisc_priv(sch);
226 int i;
227
228 for (i=0; i<TCQ_PRIO_BANDS; i++)
229 q->queues[i] = &noop_qdisc;
230
231 if (opt == NULL) {
232 return -EINVAL;
233 } else {
234 int err;
235
236 if ((err= prio_tune(sch, opt)) != 0)
237 return err;
238 }
239 return 0;
240}
241
242static int prio_dump(struct Qdisc *sch, struct sk_buff *skb)
243{
244 struct prio_sched_data *q = qdisc_priv(sch);
245 unsigned char *b = skb_tail_pointer(skb);
246 struct tc_prio_qopt opt;
247
248 opt.bands = q->bands;
249 memcpy(&opt.priomap, q->prio2band, TC_PRIO_MAX+1);
250
251 NLA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt);
252
253 return skb->len;
254
255nla_put_failure:
256 nlmsg_trim(skb, b);
257 return -1;
258}
259
260static int prio_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
261 struct Qdisc **old)
262{
263 struct prio_sched_data *q = qdisc_priv(sch);
264 unsigned long band = arg - 1;
265
266 if (new == NULL)
267 new = &noop_qdisc;
268
269 sch_tree_lock(sch);
270 *old = q->queues[band];
271 q->queues[band] = new;
272 qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
273 qdisc_reset(*old);
274 sch_tree_unlock(sch);
275
276 return 0;
277}
278
279static struct Qdisc *
280prio_leaf(struct Qdisc *sch, unsigned long arg)
281{
282 struct prio_sched_data *q = qdisc_priv(sch);
283 unsigned long band = arg - 1;
284
285 return q->queues[band];
286}
287
288static unsigned long prio_get(struct Qdisc *sch, u32 classid)
289{
290 struct prio_sched_data *q = qdisc_priv(sch);
291 unsigned long band = TC_H_MIN(classid);
292
293 if (band - 1 >= q->bands)
294 return 0;
295 return band;
296}
297
298static unsigned long prio_bind(struct Qdisc *sch, unsigned long parent, u32 classid)
299{
300 return prio_get(sch, classid);
301}
302
303
304static void prio_put(struct Qdisc *q, unsigned long cl)
305{
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
