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8#include <linux/module.h>
9#include <linux/slab.h>
10#include <linux/types.h>
11#include <linux/kernel.h>
12#include <linux/string.h>
13#include <linux/errno.h>
14#include <linux/skbuff.h>
15#include <net/netlink.h>
16#include <net/pkt_sched.h>
17#include <net/pkt_cls.h>
18
19struct multiq_sched_data {
20 u16 bands;
21 u16 max_bands;
22 u16 curband;
23 struct tcf_proto __rcu *filter_list;
24 struct tcf_block *block;
25 struct Qdisc **queues;
26};
27
28
29static struct Qdisc *
30multiq_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
31{
32 struct multiq_sched_data *q = qdisc_priv(sch);
33 u32 band;
34 struct tcf_result res;
35 struct tcf_proto *fl = rcu_dereference_bh(q->filter_list);
36 int err;
37
38 *qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
39 err = tcf_classify(skb, fl, &res, false);
40#ifdef CONFIG_NET_CLS_ACT
41 switch (err) {
42 case TC_ACT_STOLEN:
43 case TC_ACT_QUEUED:
44 case TC_ACT_TRAP:
45 *qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
46
47 case TC_ACT_SHOT:
48 return NULL;
49 }
50#endif
51 band = skb_get_queue_mapping(skb);
52
53 if (band >= q->bands)
54 return q->queues[0];
55
56 return q->queues[band];
57}
58
59static int
60multiq_enqueue(struct sk_buff *skb, struct Qdisc *sch,
61 struct sk_buff **to_free)
62{
63 struct Qdisc *qdisc;
64 int ret;
65
66 qdisc = multiq_classify(skb, sch, &ret);
67#ifdef CONFIG_NET_CLS_ACT
68 if (qdisc == NULL) {
69
70 if (ret & __NET_XMIT_BYPASS)
71 qdisc_qstats_drop(sch);
72 __qdisc_drop(skb, to_free);
73 return ret;
74 }
75#endif
76
77 ret = qdisc_enqueue(skb, qdisc, to_free);
78 if (ret == NET_XMIT_SUCCESS) {
79 sch->q.qlen++;
80 return NET_XMIT_SUCCESS;
81 }
82 if (net_xmit_drop_count(ret))
83 qdisc_qstats_drop(sch);
84 return ret;
85}
86
87static struct sk_buff *multiq_dequeue(struct Qdisc *sch)
88{
89 struct multiq_sched_data *q = qdisc_priv(sch);
90 struct Qdisc *qdisc;
91 struct sk_buff *skb;
92 int band;
93
94 for (band = 0; band < q->bands; band++) {
95
96 q->curband++;
97 if (q->curband >= q->bands)
98 q->curband = 0;
99
100
101
102
103 if (!netif_xmit_stopped(
104 netdev_get_tx_queue(qdisc_dev(sch), q->curband))) {
105 qdisc = q->queues[q->curband];
106 skb = qdisc->dequeue(qdisc);
107 if (skb) {
108 qdisc_bstats_update(sch, skb);
109 sch->q.qlen--;
110 return skb;
111 }
112 }
113 }
114 return NULL;
115
116}
117
118static struct sk_buff *multiq_peek(struct Qdisc *sch)
119{
120 struct multiq_sched_data *q = qdisc_priv(sch);
121 unsigned int curband = q->curband;
122 struct Qdisc *qdisc;
123 struct sk_buff *skb;
124 int band;
125
126 for (band = 0; band < q->bands; band++) {
127
128 curband++;
129 if (curband >= q->bands)
130 curband = 0;
131
132
133
134
135 if (!netif_xmit_stopped(
136 netdev_get_tx_queue(qdisc_dev(sch), curband))) {
137 qdisc = q->queues[curband];
138 skb = qdisc->ops->peek(qdisc);
139 if (skb)
140 return skb;
141 }
142 }
143 return NULL;
144
145}
146
147static void
148multiq_reset(struct Qdisc *sch)
149{
150 u16 band;
151 struct multiq_sched_data *q = qdisc_priv(sch);
152
153 for (band = 0; band < q->bands; band++)
154 qdisc_reset(q->queues[band]);
155 sch->q.qlen = 0;
156 q->curband = 0;
157}
158
159static void
160multiq_destroy(struct Qdisc *sch)
161{
162 int band;
163 struct multiq_sched_data *q = qdisc_priv(sch);
164
165 tcf_block_put(q->block);
166 for (band = 0; band < q->bands; band++)
167 qdisc_put(q->queues[band]);
168
169 kfree(q->queues);
170}
171
172static int multiq_tune(struct Qdisc *sch, struct nlattr *opt,
173 struct netlink_ext_ack *extack)
174{
175 struct multiq_sched_data *q = qdisc_priv(sch);
176 struct tc_multiq_qopt *qopt;
177 int i;
178
179 if (!netif_is_multiqueue(qdisc_dev(sch)))
180 return -EOPNOTSUPP;
181 if (nla_len(opt) < sizeof(*qopt))
182 return -EINVAL;
183
184 qopt = nla_data(opt);
185
186 qopt->bands = qdisc_dev(sch)->real_num_tx_queues;
187
188 sch_tree_lock(sch);
189 q->bands = qopt->bands;
190 for (i = q->bands; i < q->max_bands; i++) {
191 if (q->queues[i] != &noop_qdisc) {
192 struct Qdisc *child = q->queues[i];
193
194 q->queues[i] = &noop_qdisc;
195 qdisc_tree_flush_backlog(child);
196 qdisc_put(child);
197 }
198 }
199
200 sch_tree_unlock(sch);
201
202 for (i = 0; i < q->bands; i++) {
203 if (q->queues[i] == &noop_qdisc) {
204 struct Qdisc *child, *old;
205 child = qdisc_create_dflt(sch->dev_queue,
206 &pfifo_qdisc_ops,
207 TC_H_MAKE(sch->handle,
208 i + 1), extack);
209 if (child) {
210 sch_tree_lock(sch);
211 old = q->queues[i];
212 q->queues[i] = child;
213 if (child != &noop_qdisc)
214 qdisc_hash_add(child, true);
215
216 if (old != &noop_qdisc) {
217 qdisc_tree_flush_backlog(old);
218 qdisc_put(old);
219 }
220 sch_tree_unlock(sch);
221 }
222 }
223 }
224 return 0;
225}
226
227static int multiq_init(struct Qdisc *sch, struct nlattr *opt,
228 struct netlink_ext_ack *extack)
229{
230 struct multiq_sched_data *q = qdisc_priv(sch);
231 int i, err;
232
233 q->queues = NULL;
234
235 if (!opt)
236 return -EINVAL;
237
238 err = tcf_block_get(&q->block, &q->filter_list, sch, extack);
239 if (err)
240 return err;
241
242 q->max_bands = qdisc_dev(sch)->num_tx_queues;
243
244 q->queues = kcalloc(q->max_bands, sizeof(struct Qdisc *), GFP_KERNEL);
245 if (!q->queues)
246 return -ENOBUFS;
247 for (i = 0; i < q->max_bands; i++)
248 q->queues[i] = &noop_qdisc;
249
250 return multiq_tune(sch, opt, extack);
251}
252
253static int multiq_dump(struct Qdisc *sch, struct sk_buff *skb)
254{
255 struct multiq_sched_data *q = qdisc_priv(sch);
256 unsigned char *b = skb_tail_pointer(skb);
257 struct tc_multiq_qopt opt;
258
259 opt.bands = q->bands;
260 opt.max_bands = q->max_bands;
261
262 if (nla_put(skb, TCA_OPTIONS, sizeof(opt), &opt))
263 goto nla_put_failure;
264
265 return skb->len;
266
267nla_put_failure:
268 nlmsg_trim(skb, b);
269 return -1;
270}
271
272static int multiq_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
273 struct Qdisc **old, struct netlink_ext_ack *extack)
274{
275 struct multiq_sched_data *q = qdisc_priv(sch);
276 unsigned long band = arg - 1;
277
278 if (new == NULL)
279 new = &noop_qdisc;
280
281 *old = qdisc_replace(sch, new, &q->queues[band]);
282 return 0;
283}
284
285static struct Qdisc *
286multiq_leaf(struct Qdisc *sch, unsigned long arg)
287{
288 struct multiq_sched_data *q = qdisc_priv(sch);
289 unsigned long band = arg - 1;
290
291 return q->queues[band];
292}
293
294static unsigned long multiq_find(struct Qdisc *sch, u32 classid)
295{
296 struct multiq_sched_data *q = qdisc_priv(sch);
297 unsigned long band = TC_H_MIN(classid);
298
299 if (band - 1 >= q->bands)
300 return 0;
301 return band;
302}
303
304static unsigned long multiq_bind(struct Qdisc *sch, unsigned long parent,
305 u32 classid)
306{
307 return multiq_find(sch, classid);
308}
309
310
311static void multiq_unbind(struct Qdisc *q, unsigned long cl)
312{
313}
314
315static int multiq_dump_class(struct Qdisc *sch, unsigned long cl,
316 struct sk_buff *skb, struct tcmsg *tcm)
317{
318 struct multiq_sched_data *q = qdisc_priv(sch);
319
320 tcm->tcm_handle |= TC_H_MIN(cl);
321 tcm->tcm_info = q->queues[cl - 1]->handle;
322 return 0;
323}
324
325static int multiq_dump_class_stats(struct Qdisc *sch, unsigned long cl,
326 struct gnet_dump *d)
327{
328 struct multiq_sched_data *q = qdisc_priv(sch);
329 struct Qdisc *cl_q;
330
331 cl_q = q->queues[cl - 1];
332 if (gnet_stats_copy_basic(qdisc_root_sleeping_running(sch),
333 d, NULL, &cl_q->bstats) < 0 ||
334 qdisc_qstats_copy(d, cl_q) < 0)
335 return -1;
336
337 return 0;
338}
339
340static void multiq_walk(struct Qdisc *sch, struct qdisc_walker *arg)
341{
342 struct multiq_sched_data *q = qdisc_priv(sch);
343 int band;
344
345 if (arg->stop)
346 return;
347
348 for (band = 0; band < q->bands; band++) {
349 if (arg->count < arg->skip) {
350 arg->count++;
351 continue;
352 }
353 if (arg->fn(sch, band + 1, arg) < 0) {
354 arg->stop = 1;
355 break;
356 }
357 arg->count++;
358 }
359}
360
361static struct tcf_block *multiq_tcf_block(struct Qdisc *sch, unsigned long cl,
362 struct netlink_ext_ack *extack)
363{
364 struct multiq_sched_data *q = qdisc_priv(sch);
365
366 if (cl)
367 return NULL;
368 return q->block;
369}
370
371static const struct Qdisc_class_ops multiq_class_ops = {
372 .graft = multiq_graft,
373 .leaf = multiq_leaf,
374 .find = multiq_find,
375 .walk = multiq_walk,
376 .tcf_block = multiq_tcf_block,
377 .bind_tcf = multiq_bind,
378 .unbind_tcf = multiq_unbind,
379 .dump = multiq_dump_class,
380 .dump_stats = multiq_dump_class_stats,
381};
382
383static struct Qdisc_ops multiq_qdisc_ops __read_mostly = {
384 .next = NULL,
385 .cl_ops = &multiq_class_ops,
386 .id = "multiq",
387 .priv_size = sizeof(struct multiq_sched_data),
388 .enqueue = multiq_enqueue,
389 .dequeue = multiq_dequeue,
390 .peek = multiq_peek,
391 .init = multiq_init,
392 .reset = multiq_reset,
393 .destroy = multiq_destroy,
394 .change = multiq_tune,
395 .dump = multiq_dump,
396 .owner = THIS_MODULE,
397};
398
399static int __init multiq_module_init(void)
400{
401 return register_qdisc(&multiq_qdisc_ops);
402}
403
404static void __exit multiq_module_exit(void)
405{
406 unregister_qdisc(&multiq_qdisc_ops);
407}
408
409module_init(multiq_module_init)
410module_exit(multiq_module_exit)
411
412MODULE_LICENSE("GPL");
413
