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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * net/sched/sch_prio.c Simple 3-band priority "scheduler".
4 *
5 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
6 * Fixes: 19990609: J Hadi Salim <hadi@nortelnetworks.com>:
7 * Init -- EINVAL when opt undefined
8 */
9
10#include <linux/module.h>
11#include <linux/slab.h>
12#include <linux/types.h>
13#include <linux/kernel.h>
14#include <linux/string.h>
15#include <linux/errno.h>
16#include <linux/skbuff.h>
17#include <net/netlink.h>
18#include <net/pkt_sched.h>
19#include <net/pkt_cls.h>
20
21struct prio_sched_data {
22 int bands;
23 struct tcf_proto __rcu *filter_list;
24 struct tcf_block *block;
25 u8 prio2band[TC_PRIO_MAX+1];
26 struct Qdisc *queues[TCQ_PRIO_BANDS];
27};
28
29
30static struct Qdisc *
31prio_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
32{
33 struct prio_sched_data *q = qdisc_priv(sch);
34 u32 band = skb->priority;
35 struct tcf_result res;
36 struct tcf_proto *fl;
37 int err;
38
39 *qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
40 if (TC_H_MAJ(skb->priority) != sch->handle) {
41 fl = rcu_dereference_bh(q->filter_list);
42 err = tcf_classify(skb, NULL, fl, &res, false);
43#ifdef CONFIG_NET_CLS_ACT
44 switch (err) {
45 case TC_ACT_STOLEN:
46 case TC_ACT_QUEUED:
47 case TC_ACT_TRAP:
48 *qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
49 fallthrough;
50 case TC_ACT_SHOT:
51 return NULL;
52 }
53#endif
54 if (!fl || 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, struct sk_buff **to_free)
70{
71 unsigned int len = qdisc_pkt_len(skb);
72 struct Qdisc *qdisc;
73 int ret;
74
75 qdisc = prio_classify(skb, sch, &ret);
76#ifdef CONFIG_NET_CLS_ACT
77 if (qdisc == NULL) {
78
79 if (ret & __NET_XMIT_BYPASS)
80 qdisc_qstats_drop(sch);
81 __qdisc_drop(skb, to_free);
82 return ret;
83 }
84#endif
85
86 ret = qdisc_enqueue(skb, qdisc, to_free);
87 if (ret == NET_XMIT_SUCCESS) {
88 sch->qstats.backlog += len;
89 sch->q.qlen++;
90 return NET_XMIT_SUCCESS;
91 }
92 if (net_xmit_drop_count(ret))
93 qdisc_qstats_drop(sch);
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_peeked(qdisc);
119 if (skb) {
120 qdisc_bstats_update(sch, skb);
121 qdisc_qstats_backlog_dec(sch, skb);
122 sch->q.qlen--;
123 return skb;
124 }
125 }
126 return NULL;
127
128}
129
130static void
131prio_reset(struct Qdisc *sch)
132{
133 int prio;
134 struct prio_sched_data *q = qdisc_priv(sch);
135
136 for (prio = 0; prio < q->bands; prio++)
137 qdisc_reset(q->queues[prio]);
138}
139
140static int prio_offload(struct Qdisc *sch, struct tc_prio_qopt *qopt)
141{
142 struct net_device *dev = qdisc_dev(sch);
143 struct tc_prio_qopt_offload opt = {
144 .handle = sch->handle,
145 .parent = sch->parent,
146 };
147
148 if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc)
149 return -EOPNOTSUPP;
150
151 if (qopt) {
152 opt.command = TC_PRIO_REPLACE;
153 opt.replace_params.bands = qopt->bands;
154 memcpy(&opt.replace_params.priomap, qopt->priomap,
155 TC_PRIO_MAX + 1);
156 opt.replace_params.qstats = &sch->qstats;
157 } else {
158 opt.command = TC_PRIO_DESTROY;
159 }
160
161 return dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_QDISC_PRIO, &opt);
162}
163
164static void
165prio_destroy(struct Qdisc *sch)
166{
167 int prio;
168 struct prio_sched_data *q = qdisc_priv(sch);
169
170 tcf_block_put(q->block);
171 prio_offload(sch, NULL);
172 for (prio = 0; prio < q->bands; prio++)
173 qdisc_put(q->queues[prio]);
174}
175
176static int prio_tune(struct Qdisc *sch, struct nlattr *opt,
177 struct netlink_ext_ack *extack)
178{
179 struct prio_sched_data *q = qdisc_priv(sch);
180 struct Qdisc *queues[TCQ_PRIO_BANDS];
181 int oldbands = q->bands, i;
182 struct tc_prio_qopt *qopt;
183
184 if (nla_len(opt) < sizeof(*qopt))
185 return -EINVAL;
186 qopt = nla_data(opt);
187
188 if (qopt->bands > TCQ_PRIO_BANDS || qopt->bands < TCQ_MIN_PRIO_BANDS)
189 return -EINVAL;
190
191 for (i = 0; i <= TC_PRIO_MAX; i++) {
192 if (qopt->priomap[i] >= qopt->bands)
193 return -EINVAL;
194 }
195
196 /* Before commit, make sure we can allocate all new qdiscs */
197 for (i = oldbands; i < qopt->bands; i++) {
198 queues[i] = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops,
199 TC_H_MAKE(sch->handle, i + 1),
200 extack);
201 if (!queues[i]) {
202 while (i > oldbands)
203 qdisc_put(queues[--i]);
204 return -ENOMEM;
205 }
206 }
207
208 prio_offload(sch, qopt);
209 sch_tree_lock(sch);
210 q->bands = qopt->bands;
211 memcpy(q->prio2band, qopt->priomap, TC_PRIO_MAX+1);
212
213 for (i = q->bands; i < oldbands; i++)
214 qdisc_tree_flush_backlog(q->queues[i]);
215
216 for (i = oldbands; i < q->bands; i++) {
217 q->queues[i] = queues[i];
218 if (q->queues[i] != &noop_qdisc)
219 qdisc_hash_add(q->queues[i], true);
220 }
221
222 sch_tree_unlock(sch);
223
224 for (i = q->bands; i < oldbands; i++)
225 qdisc_put(q->queues[i]);
226 return 0;
227}
228
229static int prio_init(struct Qdisc *sch, struct nlattr *opt,
230 struct netlink_ext_ack *extack)
231{
232 struct prio_sched_data *q = qdisc_priv(sch);
233 int err;
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 return prio_tune(sch, opt, extack);
243}
244
245static int prio_dump_offload(struct Qdisc *sch)
246{
247 struct tc_prio_qopt_offload hw_stats = {
248 .command = TC_PRIO_STATS,
249 .handle = sch->handle,
250 .parent = sch->parent,
251 {
252 .stats = {
253 .bstats = &sch->bstats,
254 .qstats = &sch->qstats,
255 },
256 },
257 };
258
259 return qdisc_offload_dump_helper(sch, TC_SETUP_QDISC_PRIO, &hw_stats);
260}
261
262static int prio_dump(struct Qdisc *sch, struct sk_buff *skb)
263{
264 struct prio_sched_data *q = qdisc_priv(sch);
265 unsigned char *b = skb_tail_pointer(skb);
266 struct tc_prio_qopt opt;
267 int err;
268
269 opt.bands = q->bands;
270 memcpy(&opt.priomap, q->prio2band, TC_PRIO_MAX + 1);
271
272 err = prio_dump_offload(sch);
273 if (err)
274 goto nla_put_failure;
275
276 if (nla_put(skb, TCA_OPTIONS, sizeof(opt), &opt))
277 goto nla_put_failure;
278
279 return skb->len;
280
281nla_put_failure:
282 nlmsg_trim(skb, b);
283 return -1;
284}
285
286static int prio_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
287 struct Qdisc **old, struct netlink_ext_ack *extack)
288{
289 struct prio_sched_data *q = qdisc_priv(sch);
290 struct tc_prio_qopt_offload graft_offload;
291 unsigned long band = arg - 1;
292
293 if (!new) {
294 new = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops,
295 TC_H_MAKE(sch->handle, arg), extack);
296 if (!new)
297 new = &noop_qdisc;
298 else
299 qdisc_hash_add(new, true);
300 }
301
302 *old = qdisc_replace(sch, new, &q->queues[band]);
303
304 graft_offload.handle = sch->handle;
305 graft_offload.parent = sch->parent;
306 graft_offload.graft_params.band = band;
307 graft_offload.graft_params.child_handle = new->handle;
308 graft_offload.command = TC_PRIO_GRAFT;
309
310 qdisc_offload_graft_helper(qdisc_dev(sch), sch, new, *old,
311 TC_SETUP_QDISC_PRIO, &graft_offload,
312 extack);
313 return 0;
314}
315
316static struct Qdisc *
317prio_leaf(struct Qdisc *sch, unsigned long arg)
318{
319 struct prio_sched_data *q = qdisc_priv(sch);
320 unsigned long band = arg - 1;
321
322 return q->queues[band];
323}
324
325static unsigned long prio_find(struct Qdisc *sch, u32 classid)
326{
327 struct prio_sched_data *q = qdisc_priv(sch);
328 unsigned long band = TC_H_MIN(classid);
329
330 if (band - 1 >= q->bands)
331 return 0;
332 return band;
333}
334
335static unsigned long prio_bind(struct Qdisc *sch, unsigned long parent, u32 classid)
336{
337 return prio_find(sch, classid);
338}
339
340
341static void prio_unbind(struct Qdisc *q, unsigned long cl)
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 tcm->tcm_handle |= TC_H_MIN(cl);
351 tcm->tcm_info = q->queues[cl-1]->handle;
352 return 0;
353}
354
355static int prio_dump_class_stats(struct Qdisc *sch, unsigned long cl,
356 struct gnet_dump *d)
357{
358 struct prio_sched_data *q = qdisc_priv(sch);
359 struct Qdisc *cl_q;
360
361 cl_q = q->queues[cl - 1];
362 if (gnet_stats_copy_basic(d, cl_q->cpu_bstats,
363 &cl_q->bstats, true) < 0 ||
364 qdisc_qstats_copy(d, cl_q) < 0)
365 return -1;
366
367 return 0;
368}
369
370static void prio_walk(struct Qdisc *sch, struct qdisc_walker *arg)
371{
372 struct prio_sched_data *q = qdisc_priv(sch);
373 int prio;
374
375 if (arg->stop)
376 return;
377
378 for (prio = 0; prio < q->bands; prio++) {
379 if (!tc_qdisc_stats_dump(sch, prio + 1, arg))
380 break;
381 }
382}
383
384static struct tcf_block *prio_tcf_block(struct Qdisc *sch, unsigned long cl,
385 struct netlink_ext_ack *extack)
386{
387 struct prio_sched_data *q = qdisc_priv(sch);
388
389 if (cl)
390 return NULL;
391 return q->block;
392}
393
394static const struct Qdisc_class_ops prio_class_ops = {
395 .graft = prio_graft,
396 .leaf = prio_leaf,
397 .find = prio_find,
398 .walk = prio_walk,
399 .tcf_block = prio_tcf_block,
400 .bind_tcf = prio_bind,
401 .unbind_tcf = prio_unbind,
402 .dump = prio_dump_class,
403 .dump_stats = prio_dump_class_stats,
404};
405
406static struct Qdisc_ops prio_qdisc_ops __read_mostly = {
407 .next = NULL,
408 .cl_ops = &prio_class_ops,
409 .id = "prio",
410 .priv_size = sizeof(struct prio_sched_data),
411 .enqueue = prio_enqueue,
412 .dequeue = prio_dequeue,
413 .peek = prio_peek,
414 .init = prio_init,
415 .reset = prio_reset,
416 .destroy = prio_destroy,
417 .change = prio_tune,
418 .dump = prio_dump,
419 .owner = THIS_MODULE,
420};
421MODULE_ALIAS_NET_SCH("prio");
422
423static int __init prio_module_init(void)
424{
425 return register_qdisc(&prio_qdisc_ops);
426}
427
428static void __exit prio_module_exit(void)
429{
430 unregister_qdisc(&prio_qdisc_ops);
431}
432
433module_init(prio_module_init)
434module_exit(prio_module_exit)
435
436MODULE_LICENSE("GPL");
437MODULE_DESCRIPTION("Simple 3-band priority qdisc");
1/*
2 * net/sched/sch_prio.c Simple 3-band priority "scheduler".
3 *
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.
8 *
9 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
10 * Fixes: 19990609: J Hadi Salim <hadi@nortelnetworks.com>:
11 * Init -- EINVAL when opt undefined
12 */
13
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#include <net/pkt_cls.h>
24
25struct prio_sched_data {
26 int bands;
27 struct tcf_proto __rcu *filter_list;
28 struct tcf_block *block;
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 struct tcf_proto *fl;
41 int err;
42
43 *qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
44 if (TC_H_MAJ(skb->priority) != sch->handle) {
45 fl = rcu_dereference_bh(q->filter_list);
46 err = tcf_classify(skb, fl, &res, false);
47#ifdef CONFIG_NET_CLS_ACT
48 switch (err) {
49 case TC_ACT_STOLEN:
50 case TC_ACT_QUEUED:
51 case TC_ACT_TRAP:
52 *qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
53 /* fall through */
54 case TC_ACT_SHOT:
55 return NULL;
56 }
57#endif
58 if (!fl || err < 0) {
59 if (TC_H_MAJ(band))
60 band = 0;
61 return q->queues[q->prio2band[band & TC_PRIO_MAX]];
62 }
63 band = res.classid;
64 }
65 band = TC_H_MIN(band) - 1;
66 if (band >= q->bands)
67 return q->queues[q->prio2band[0]];
68
69 return q->queues[band];
70}
71
72static int
73prio_enqueue(struct sk_buff *skb, struct Qdisc *sch, struct sk_buff **to_free)
74{
75 struct Qdisc *qdisc;
76 int ret;
77
78 qdisc = prio_classify(skb, sch, &ret);
79#ifdef CONFIG_NET_CLS_ACT
80 if (qdisc == NULL) {
81
82 if (ret & __NET_XMIT_BYPASS)
83 qdisc_qstats_drop(sch);
84 __qdisc_drop(skb, to_free);
85 return ret;
86 }
87#endif
88
89 ret = qdisc_enqueue(skb, qdisc, to_free);
90 if (ret == NET_XMIT_SUCCESS) {
91 qdisc_qstats_backlog_inc(sch, skb);
92 sch->q.qlen++;
93 return NET_XMIT_SUCCESS;
94 }
95 if (net_xmit_drop_count(ret))
96 qdisc_qstats_drop(sch);
97 return ret;
98}
99
100static struct sk_buff *prio_peek(struct Qdisc *sch)
101{
102 struct prio_sched_data *q = qdisc_priv(sch);
103 int prio;
104
105 for (prio = 0; prio < q->bands; prio++) {
106 struct Qdisc *qdisc = q->queues[prio];
107 struct sk_buff *skb = qdisc->ops->peek(qdisc);
108 if (skb)
109 return skb;
110 }
111 return NULL;
112}
113
114static struct sk_buff *prio_dequeue(struct Qdisc *sch)
115{
116 struct prio_sched_data *q = qdisc_priv(sch);
117 int prio;
118
119 for (prio = 0; prio < q->bands; prio++) {
120 struct Qdisc *qdisc = q->queues[prio];
121 struct sk_buff *skb = qdisc_dequeue_peeked(qdisc);
122 if (skb) {
123 qdisc_bstats_update(sch, skb);
124 qdisc_qstats_backlog_dec(sch, skb);
125 sch->q.qlen--;
126 return skb;
127 }
128 }
129 return NULL;
130
131}
132
133static void
134prio_reset(struct Qdisc *sch)
135{
136 int prio;
137 struct prio_sched_data *q = qdisc_priv(sch);
138
139 for (prio = 0; prio < q->bands; prio++)
140 qdisc_reset(q->queues[prio]);
141 sch->qstats.backlog = 0;
142 sch->q.qlen = 0;
143}
144
145static int prio_offload(struct Qdisc *sch, struct tc_prio_qopt *qopt)
146{
147 struct net_device *dev = qdisc_dev(sch);
148 struct tc_prio_qopt_offload opt = {
149 .handle = sch->handle,
150 .parent = sch->parent,
151 };
152
153 if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc)
154 return -EOPNOTSUPP;
155
156 if (qopt) {
157 opt.command = TC_PRIO_REPLACE;
158 opt.replace_params.bands = qopt->bands;
159 memcpy(&opt.replace_params.priomap, qopt->priomap,
160 TC_PRIO_MAX + 1);
161 opt.replace_params.qstats = &sch->qstats;
162 } else {
163 opt.command = TC_PRIO_DESTROY;
164 }
165
166 return dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_QDISC_PRIO, &opt);
167}
168
169static void
170prio_destroy(struct Qdisc *sch)
171{
172 int prio;
173 struct prio_sched_data *q = qdisc_priv(sch);
174
175 tcf_block_put(q->block);
176 prio_offload(sch, NULL);
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 struct netlink_ext_ack *extack)
183{
184 struct prio_sched_data *q = qdisc_priv(sch);
185 struct Qdisc *queues[TCQ_PRIO_BANDS];
186 int oldbands = q->bands, i;
187 struct tc_prio_qopt *qopt;
188
189 if (nla_len(opt) < sizeof(*qopt))
190 return -EINVAL;
191 qopt = nla_data(opt);
192
193 if (qopt->bands > TCQ_PRIO_BANDS || qopt->bands < 2)
194 return -EINVAL;
195
196 for (i = 0; i <= TC_PRIO_MAX; i++) {
197 if (qopt->priomap[i] >= qopt->bands)
198 return -EINVAL;
199 }
200
201 /* Before commit, make sure we can allocate all new qdiscs */
202 for (i = oldbands; i < qopt->bands; i++) {
203 queues[i] = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops,
204 TC_H_MAKE(sch->handle, i + 1),
205 extack);
206 if (!queues[i]) {
207 while (i > oldbands)
208 qdisc_destroy(queues[--i]);
209 return -ENOMEM;
210 }
211 }
212
213 prio_offload(sch, qopt);
214 sch_tree_lock(sch);
215 q->bands = qopt->bands;
216 memcpy(q->prio2band, qopt->priomap, TC_PRIO_MAX+1);
217
218 for (i = q->bands; i < oldbands; i++) {
219 struct Qdisc *child = q->queues[i];
220
221 qdisc_tree_reduce_backlog(child, child->q.qlen,
222 child->qstats.backlog);
223 qdisc_destroy(child);
224 }
225
226 for (i = oldbands; i < q->bands; i++) {
227 q->queues[i] = queues[i];
228 if (q->queues[i] != &noop_qdisc)
229 qdisc_hash_add(q->queues[i], true);
230 }
231
232 sch_tree_unlock(sch);
233 return 0;
234}
235
236static int prio_init(struct Qdisc *sch, struct nlattr *opt,
237 struct netlink_ext_ack *extack)
238{
239 struct prio_sched_data *q = qdisc_priv(sch);
240 int err;
241
242 if (!opt)
243 return -EINVAL;
244
245 err = tcf_block_get(&q->block, &q->filter_list, sch, extack);
246 if (err)
247 return err;
248
249 return prio_tune(sch, opt, extack);
250}
251
252static int prio_dump_offload(struct Qdisc *sch)
253{
254 struct net_device *dev = qdisc_dev(sch);
255 struct tc_prio_qopt_offload hw_stats = {
256 .command = TC_PRIO_STATS,
257 .handle = sch->handle,
258 .parent = sch->parent,
259 {
260 .stats = {
261 .bstats = &sch->bstats,
262 .qstats = &sch->qstats,
263 },
264 },
265 };
266 int err;
267
268 sch->flags &= ~TCQ_F_OFFLOADED;
269 if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc)
270 return 0;
271
272 err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_QDISC_PRIO,
273 &hw_stats);
274 if (err == -EOPNOTSUPP)
275 return 0;
276
277 if (!err)
278 sch->flags |= TCQ_F_OFFLOADED;
279
280 return err;
281}
282
283static int prio_dump(struct Qdisc *sch, struct sk_buff *skb)
284{
285 struct prio_sched_data *q = qdisc_priv(sch);
286 unsigned char *b = skb_tail_pointer(skb);
287 struct tc_prio_qopt opt;
288 int err;
289
290 opt.bands = q->bands;
291 memcpy(&opt.priomap, q->prio2band, TC_PRIO_MAX + 1);
292
293 err = prio_dump_offload(sch);
294 if (err)
295 goto nla_put_failure;
296
297 if (nla_put(skb, TCA_OPTIONS, sizeof(opt), &opt))
298 goto nla_put_failure;
299
300 return skb->len;
301
302nla_put_failure:
303 nlmsg_trim(skb, b);
304 return -1;
305}
306
307static int prio_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
308 struct Qdisc **old, struct netlink_ext_ack *extack)
309{
310 struct prio_sched_data *q = qdisc_priv(sch);
311 struct tc_prio_qopt_offload graft_offload;
312 struct net_device *dev = qdisc_dev(sch);
313 unsigned long band = arg - 1;
314 bool any_qdisc_is_offloaded;
315 int err;
316
317 if (new == NULL)
318 new = &noop_qdisc;
319
320 *old = qdisc_replace(sch, new, &q->queues[band]);
321
322 if (!tc_can_offload(dev))
323 return 0;
324
325 graft_offload.handle = sch->handle;
326 graft_offload.parent = sch->parent;
327 graft_offload.graft_params.band = band;
328 graft_offload.graft_params.child_handle = new->handle;
329 graft_offload.command = TC_PRIO_GRAFT;
330
331 err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_QDISC_PRIO,
332 &graft_offload);
333
334 /* Don't report error if the graft is part of destroy operation. */
335 if (err && new != &noop_qdisc) {
336 /* Don't report error if the parent, the old child and the new
337 * one are not offloaded.
338 */
339 any_qdisc_is_offloaded = sch->flags & TCQ_F_OFFLOADED;
340 any_qdisc_is_offloaded |= new->flags & TCQ_F_OFFLOADED;
341 if (*old)
342 any_qdisc_is_offloaded |= (*old)->flags &
343 TCQ_F_OFFLOADED;
344
345 if (any_qdisc_is_offloaded)
346 NL_SET_ERR_MSG(extack, "Offloading graft operation failed.");
347 }
348
349 return 0;
350}
351
352static struct Qdisc *
353prio_leaf(struct Qdisc *sch, unsigned long arg)
354{
355 struct prio_sched_data *q = qdisc_priv(sch);
356 unsigned long band = arg - 1;
357
358 return q->queues[band];
359}
360
361static unsigned long prio_find(struct Qdisc *sch, u32 classid)
362{
363 struct prio_sched_data *q = qdisc_priv(sch);
364 unsigned long band = TC_H_MIN(classid);
365
366 if (band - 1 >= q->bands)
367 return 0;
368 return band;
369}
370
371static unsigned long prio_bind(struct Qdisc *sch, unsigned long parent, u32 classid)
372{
373 return prio_find(sch, classid);
374}
375
376
377static void prio_unbind(struct Qdisc *q, unsigned long cl)
378{
379}
380
381static int prio_dump_class(struct Qdisc *sch, unsigned long cl, struct sk_buff *skb,
382 struct tcmsg *tcm)
383{
384 struct prio_sched_data *q = qdisc_priv(sch);
385
386 tcm->tcm_handle |= TC_H_MIN(cl);
387 tcm->tcm_info = q->queues[cl-1]->handle;
388 return 0;
389}
390
391static int prio_dump_class_stats(struct Qdisc *sch, unsigned long cl,
392 struct gnet_dump *d)
393{
394 struct prio_sched_data *q = qdisc_priv(sch);
395 struct Qdisc *cl_q;
396
397 cl_q = q->queues[cl - 1];
398 if (gnet_stats_copy_basic(qdisc_root_sleeping_running(sch),
399 d, NULL, &cl_q->bstats) < 0 ||
400 gnet_stats_copy_queue(d, NULL, &cl_q->qstats, cl_q->q.qlen) < 0)
401 return -1;
402
403 return 0;
404}
405
406static void prio_walk(struct Qdisc *sch, struct qdisc_walker *arg)
407{
408 struct prio_sched_data *q = qdisc_priv(sch);
409 int prio;
410
411 if (arg->stop)
412 return;
413
414 for (prio = 0; prio < q->bands; prio++) {
415 if (arg->count < arg->skip) {
416 arg->count++;
417 continue;
418 }
419 if (arg->fn(sch, prio + 1, arg) < 0) {
420 arg->stop = 1;
421 break;
422 }
423 arg->count++;
424 }
425}
426
427static struct tcf_block *prio_tcf_block(struct Qdisc *sch, unsigned long cl,
428 struct netlink_ext_ack *extack)
429{
430 struct prio_sched_data *q = qdisc_priv(sch);
431
432 if (cl)
433 return NULL;
434 return q->block;
435}
436
437static const struct Qdisc_class_ops prio_class_ops = {
438 .graft = prio_graft,
439 .leaf = prio_leaf,
440 .find = prio_find,
441 .walk = prio_walk,
442 .tcf_block = prio_tcf_block,
443 .bind_tcf = prio_bind,
444 .unbind_tcf = prio_unbind,
445 .dump = prio_dump_class,
446 .dump_stats = prio_dump_class_stats,
447};
448
449static struct Qdisc_ops prio_qdisc_ops __read_mostly = {
450 .next = NULL,
451 .cl_ops = &prio_class_ops,
452 .id = "prio",
453 .priv_size = sizeof(struct prio_sched_data),
454 .enqueue = prio_enqueue,
455 .dequeue = prio_dequeue,
456 .peek = prio_peek,
457 .init = prio_init,
458 .reset = prio_reset,
459 .destroy = prio_destroy,
460 .change = prio_tune,
461 .dump = prio_dump,
462 .owner = THIS_MODULE,
463};
464
465static int __init prio_module_init(void)
466{
467 return register_qdisc(&prio_qdisc_ops);
468}
469
470static void __exit prio_module_exit(void)
471{
472 unregister_qdisc(&prio_qdisc_ops);
473}
474
475module_init(prio_module_init)
476module_exit(prio_module_exit)
477
478MODULE_LICENSE("GPL");