Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/shaggy...
[linux-2.6-block.git] / net / sched / sch_dsmark.c
CommitLineData
1da177e4
LT
1/* net/sched/sch_dsmark.c - Differentiated Services field marker */
2
3/* Written 1998-2000 by Werner Almesberger, EPFL ICA */
4
5
1da177e4
LT
6#include <linux/module.h>
7#include <linux/init.h>
8#include <linux/types.h>
9#include <linux/string.h>
10#include <linux/errno.h>
11#include <linux/skbuff.h>
1da177e4 12#include <linux/rtnetlink.h>
5b0ac72b 13#include <linux/bitops.h>
1da177e4
LT
14#include <net/pkt_sched.h>
15#include <net/dsfield.h>
16#include <net/inet_ecn.h>
17#include <asm/byteorder.h>
18
1da177e4
LT
19/*
20 * classid class marking
21 * ------- ----- -------
22 * n/a 0 n/a
23 * x:0 1 use entry [0]
24 * ... ... ...
25 * x:y y>0 y+1 use entry [y]
26 * ... ... ...
27 * x:indices-1 indices use entry [indices-1]
28 * ... ... ...
29 * x:y y+1 use entry [y & (indices-1)]
30 * ... ... ...
31 * 0xffff 0x10000 use entry [indices-1]
32 */
33
34
35#define NO_DEFAULT_INDEX (1 << 16)
36
37struct dsmark_qdisc_data {
38 struct Qdisc *q;
39 struct tcf_proto *filter_list;
af0d1141
TG
40 u8 *mask; /* "owns" the array */
41 u8 *value;
42 u16 indices;
43 u32 default_index; /* index range is 0...0xffff */
1da177e4
LT
44 int set_tc_index;
45};
46
758cc43c
TG
47static inline int dsmark_valid_index(struct dsmark_qdisc_data *p, u16 index)
48{
49 return (index <= p->indices && index > 0);
50}
1da177e4
LT
51
52/* ------------------------- Class/flow operations ------------------------- */
53
af0d1141
TG
54static int dsmark_graft(struct Qdisc *sch, unsigned long arg,
55 struct Qdisc *new, struct Qdisc **old)
1da177e4 56{
81da99ed 57 struct dsmark_qdisc_data *p = qdisc_priv(sch);
1da177e4 58
81da99ed 59 pr_debug("dsmark_graft(sch %p,[qdisc %p],new %p,old %p)\n",
af0d1141 60 sch, p, new, old);
486b53e5
TG
61
62 if (new == NULL) {
5ce2d488 63 new = qdisc_create_dflt(qdisc_dev(sch), sch->dev_queue,
bb949fbd 64 &pfifo_qdisc_ops,
9f9afec4 65 sch->handle);
486b53e5
TG
66 if (new == NULL)
67 new = &noop_qdisc;
68 }
69
1da177e4 70 sch_tree_lock(sch);
b94c8afc
PM
71 *old = p->q;
72 p->q = new;
5e50da01 73 qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
af0d1141 74 qdisc_reset(*old);
af0d1141
TG
75 sch_tree_unlock(sch);
76
10297b99 77 return 0;
1da177e4
LT
78}
79
1da177e4
LT
80static struct Qdisc *dsmark_leaf(struct Qdisc *sch, unsigned long arg)
81{
81da99ed
SH
82 struct dsmark_qdisc_data *p = qdisc_priv(sch);
83 return p->q;
1da177e4
LT
84}
85
af0d1141 86static unsigned long dsmark_get(struct Qdisc *sch, u32 classid)
1da177e4 87{
81da99ed
SH
88 pr_debug("dsmark_get(sch %p,[qdisc %p],classid %x)\n",
89 sch, qdisc_priv(sch), classid);
1da177e4 90
af0d1141 91 return TC_H_MIN(classid) + 1;
1da177e4
LT
92}
93
1da177e4 94static unsigned long dsmark_bind_filter(struct Qdisc *sch,
af0d1141 95 unsigned long parent, u32 classid)
1da177e4 96{
af0d1141 97 return dsmark_get(sch, classid);
1da177e4
LT
98}
99
1da177e4
LT
100static void dsmark_put(struct Qdisc *sch, unsigned long cl)
101{
102}
103
27a3421e
PM
104static const struct nla_policy dsmark_policy[TCA_DSMARK_MAX + 1] = {
105 [TCA_DSMARK_INDICES] = { .type = NLA_U16 },
106 [TCA_DSMARK_DEFAULT_INDEX] = { .type = NLA_U16 },
107 [TCA_DSMARK_SET_TC_INDEX] = { .type = NLA_FLAG },
108 [TCA_DSMARK_MASK] = { .type = NLA_U8 },
109 [TCA_DSMARK_VALUE] = { .type = NLA_U8 },
110};
111
1da177e4 112static int dsmark_change(struct Qdisc *sch, u32 classid, u32 parent,
1e90474c 113 struct nlattr **tca, unsigned long *arg)
1da177e4 114{
81da99ed 115 struct dsmark_qdisc_data *p = qdisc_priv(sch);
1e90474c
PM
116 struct nlattr *opt = tca[TCA_OPTIONS];
117 struct nlattr *tb[TCA_DSMARK_MAX + 1];
758cc43c
TG
118 int err = -EINVAL;
119 u8 mask = 0;
1da177e4 120
81da99ed 121 pr_debug("dsmark_change(sch %p,[qdisc %p],classid %x,parent %x),"
758cc43c
TG
122 "arg 0x%lx\n", sch, p, classid, parent, *arg);
123
124 if (!dsmark_valid_index(p, *arg)) {
125 err = -ENOENT;
1e90474c 126 goto errout;
1da177e4 127 }
1da177e4 128
cee63723 129 if (!opt)
1e90474c 130 goto errout;
758cc43c 131
27a3421e 132 err = nla_parse_nested(tb, TCA_DSMARK_MAX, opt, dsmark_policy);
cee63723 133 if (err < 0)
27a3421e 134 goto errout;
cee63723 135
27a3421e 136 if (tb[TCA_DSMARK_MASK])
1e90474c 137 mask = nla_get_u8(tb[TCA_DSMARK_MASK]);
27a3421e
PM
138
139 if (tb[TCA_DSMARK_VALUE])
1e90474c 140 p->value[*arg-1] = nla_get_u8(tb[TCA_DSMARK_VALUE]);
10297b99 141
1e90474c 142 if (tb[TCA_DSMARK_MASK])
758cc43c
TG
143 p->mask[*arg-1] = mask;
144
145 err = 0;
146
1e90474c 147errout:
758cc43c
TG
148 return err;
149}
1da177e4 150
af0d1141 151static int dsmark_delete(struct Qdisc *sch, unsigned long arg)
1da177e4 152{
81da99ed 153 struct dsmark_qdisc_data *p = qdisc_priv(sch);
1da177e4 154
af0d1141 155 if (!dsmark_valid_index(p, arg))
1da177e4 156 return -EINVAL;
10297b99 157
1da177e4
LT
158 p->mask[arg-1] = 0xff;
159 p->value[arg-1] = 0;
af0d1141 160
1da177e4
LT
161 return 0;
162}
163
9d127fbd 164static void dsmark_walk(struct Qdisc *sch, struct qdisc_walker *walker)
1da177e4 165{
81da99ed 166 struct dsmark_qdisc_data *p = qdisc_priv(sch);
1da177e4
LT
167 int i;
168
81da99ed 169 pr_debug("dsmark_walk(sch %p,[qdisc %p],walker %p)\n", sch, p, walker);
af0d1141 170
1da177e4
LT
171 if (walker->stop)
172 return;
af0d1141 173
1da177e4
LT
174 for (i = 0; i < p->indices; i++) {
175 if (p->mask[i] == 0xff && !p->value[i])
0451eb07 176 goto ignore;
1da177e4
LT
177 if (walker->count >= walker->skip) {
178 if (walker->fn(sch, i+1, walker) < 0) {
179 walker->stop = 1;
180 break;
181 }
182 }
10297b99 183ignore:
0451eb07 184 walker->count++;
10297b99 185 }
1da177e4
LT
186}
187
9d127fbd
SH
188static inline struct tcf_proto **dsmark_find_tcf(struct Qdisc *sch,
189 unsigned long cl)
1da177e4 190{
81da99ed
SH
191 struct dsmark_qdisc_data *p = qdisc_priv(sch);
192 return &p->filter_list;
1da177e4
LT
193}
194
1da177e4
LT
195/* --------------------------- Qdisc operations ---------------------------- */
196
9d127fbd 197static int dsmark_enqueue(struct sk_buff *skb, struct Qdisc *sch)
1da177e4 198{
81da99ed 199 struct dsmark_qdisc_data *p = qdisc_priv(sch);
af0d1141
TG
200 int err;
201
81da99ed 202 pr_debug("dsmark_enqueue(skb %p,sch %p,[qdisc %p])\n", skb, sch, p);
1da177e4 203
1da177e4 204 if (p->set_tc_index) {
1da177e4 205 switch (skb->protocol) {
60678040 206 case htons(ETH_P_IP):
9d127fbd
SH
207 if (skb_cow_head(skb, sizeof(struct iphdr)))
208 goto drop;
4c30719f 209
9d127fbd
SH
210 skb->tc_index = ipv4_get_dsfield(ip_hdr(skb))
211 & ~INET_ECN_MASK;
212 break;
4c30719f 213
60678040 214 case htons(ETH_P_IPV6):
9d127fbd
SH
215 if (skb_cow_head(skb, sizeof(struct ipv6hdr)))
216 goto drop;
4c30719f 217
9d127fbd
SH
218 skb->tc_index = ipv6_get_dsfield(ipv6_hdr(skb))
219 & ~INET_ECN_MASK;
220 break;
221 default:
222 skb->tc_index = 0;
223 break;
3ff50b79 224 }
1da177e4 225 }
af0d1141
TG
226
227 if (TC_H_MAJ(skb->priority) == sch->handle)
1da177e4 228 skb->tc_index = TC_H_MIN(skb->priority);
af0d1141
TG
229 else {
230 struct tcf_result res;
231 int result = tc_classify(skb, p->filter_list, &res);
232
81da99ed 233 pr_debug("result %d class 0x%04x\n", result, res.classid);
af0d1141 234
1da177e4 235 switch (result) {
f6853e2d
PM
236#ifdef CONFIG_NET_CLS_ACT
237 case TC_ACT_QUEUED:
238 case TC_ACT_STOLEN:
239 kfree_skb(skb);
378a2f09 240 return NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
4c30719f 241
f6853e2d 242 case TC_ACT_SHOT:
4c30719f 243 goto drop;
1da177e4 244#endif
c3bc7cff 245 case TC_ACT_OK:
f6853e2d
PM
246 skb->tc_index = TC_H_MIN(res.classid);
247 break;
4c30719f 248
f6853e2d
PM
249 default:
250 if (p->default_index != NO_DEFAULT_INDEX)
251 skb->tc_index = p->default_index;
252 break;
3ff50b79 253 }
1da177e4 254 }
1da177e4 255
5f86173b 256 err = qdisc_enqueue(skb, p->q);
af0d1141 257 if (err != NET_XMIT_SUCCESS) {
378a2f09
JP
258 if (net_xmit_drop_count(err))
259 sch->qstats.drops++;
af0d1141 260 return err;
1da177e4 261 }
af0d1141 262
0abf77e5 263 sch->bstats.bytes += qdisc_pkt_len(skb);
1da177e4
LT
264 sch->bstats.packets++;
265 sch->q.qlen++;
1da177e4 266
af0d1141 267 return NET_XMIT_SUCCESS;
4c30719f
SH
268
269drop:
270 kfree_skb(skb);
271 sch->qstats.drops++;
c27f339a 272 return NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
af0d1141 273}
1da177e4
LT
274
275static struct sk_buff *dsmark_dequeue(struct Qdisc *sch)
276{
81da99ed 277 struct dsmark_qdisc_data *p = qdisc_priv(sch);
1da177e4 278 struct sk_buff *skb;
af0d1141
TG
279 u32 index;
280
81da99ed 281 pr_debug("dsmark_dequeue(sch %p,[qdisc %p])\n", sch, p);
1da177e4 282
1da177e4 283 skb = p->q->ops->dequeue(p->q);
af0d1141 284 if (skb == NULL)
1da177e4 285 return NULL;
af0d1141 286
1da177e4 287 sch->q.qlen--;
af0d1141
TG
288
289 index = skb->tc_index & (p->indices - 1);
81da99ed 290 pr_debug("index %d->%d\n", skb->tc_index, index);
af0d1141 291
1da177e4 292 switch (skb->protocol) {
60678040 293 case htons(ETH_P_IP):
9d127fbd
SH
294 ipv4_change_dsfield(ip_hdr(skb), p->mask[index],
295 p->value[index]);
1da177e4 296 break;
60678040 297 case htons(ETH_P_IPV6):
9d127fbd
SH
298 ipv6_change_dsfield(ipv6_hdr(skb), p->mask[index],
299 p->value[index]);
1da177e4 300 break;
9d127fbd
SH
301 default:
302 /*
303 * Only complain if a change was actually attempted.
304 * This way, we can send non-IP traffic through dsmark
305 * and don't need yet another qdisc as a bypass.
306 */
307 if (p->mask[index] != 0xff || p->value[index])
308 printk(KERN_WARNING
309 "dsmark_dequeue: unsupported protocol %d\n",
310 ntohs(skb->protocol));
311 break;
3ff50b79 312 }
af0d1141 313
1da177e4
LT
314 return skb;
315}
316
8e3af978
JP
317static struct sk_buff *dsmark_peek(struct Qdisc *sch)
318{
319 struct dsmark_qdisc_data *p = qdisc_priv(sch);
320
321 pr_debug("dsmark_peek(sch %p,[qdisc %p])\n", sch, p);
322
323 return p->q->ops->peek(p->q);
324}
325
1da177e4
LT
326static unsigned int dsmark_drop(struct Qdisc *sch)
327{
81da99ed 328 struct dsmark_qdisc_data *p = qdisc_priv(sch);
1da177e4 329 unsigned int len;
10297b99 330
81da99ed 331 pr_debug("dsmark_reset(sch %p,[qdisc %p])\n", sch, p);
af0d1141
TG
332
333 if (p->q->ops->drop == NULL)
1da177e4 334 return 0;
af0d1141
TG
335
336 len = p->q->ops->drop(p->q);
337 if (len)
338 sch->q.qlen--;
339
1da177e4
LT
340 return len;
341}
342
1e90474c 343static int dsmark_init(struct Qdisc *sch, struct nlattr *opt)
1da177e4 344{
81da99ed 345 struct dsmark_qdisc_data *p = qdisc_priv(sch);
1e90474c 346 struct nlattr *tb[TCA_DSMARK_MAX + 1];
758cc43c
TG
347 int err = -EINVAL;
348 u32 default_index = NO_DEFAULT_INDEX;
349 u16 indices;
350 u8 *mask;
351
81da99ed 352 pr_debug("dsmark_init(sch %p,[qdisc %p],opt %p)\n", sch, p, opt);
758cc43c 353
cee63723
PM
354 if (!opt)
355 goto errout;
356
27a3421e 357 err = nla_parse_nested(tb, TCA_DSMARK_MAX, opt, dsmark_policy);
cee63723 358 if (err < 0)
758cc43c
TG
359 goto errout;
360
cee63723 361 err = -EINVAL;
1e90474c 362 indices = nla_get_u16(tb[TCA_DSMARK_INDICES]);
5b0ac72b
DM
363
364 if (hweight32(indices) != 1)
758cc43c
TG
365 goto errout;
366
27a3421e 367 if (tb[TCA_DSMARK_DEFAULT_INDEX])
1e90474c 368 default_index = nla_get_u16(tb[TCA_DSMARK_DEFAULT_INDEX]);
758cc43c
TG
369
370 mask = kmalloc(indices * 2, GFP_KERNEL);
371 if (mask == NULL) {
372 err = -ENOMEM;
373 goto errout;
1da177e4 374 }
758cc43c
TG
375
376 p->mask = mask;
377 memset(p->mask, 0xff, indices);
378
379 p->value = p->mask + indices;
380 memset(p->value, 0, indices);
381
382 p->indices = indices;
383 p->default_index = default_index;
1e90474c 384 p->set_tc_index = nla_get_flag(tb[TCA_DSMARK_SET_TC_INDEX]);
758cc43c 385
5ce2d488 386 p->q = qdisc_create_dflt(qdisc_dev(sch), sch->dev_queue,
bb949fbd 387 &pfifo_qdisc_ops, sch->handle);
758cc43c 388 if (p->q == NULL)
1da177e4 389 p->q = &noop_qdisc;
758cc43c 390
81da99ed 391 pr_debug("dsmark_init: qdisc %p\n", p->q);
758cc43c
TG
392
393 err = 0;
394errout:
758cc43c 395 return err;
1da177e4
LT
396}
397
1da177e4
LT
398static void dsmark_reset(struct Qdisc *sch)
399{
81da99ed 400 struct dsmark_qdisc_data *p = qdisc_priv(sch);
1da177e4 401
81da99ed 402 pr_debug("dsmark_reset(sch %p,[qdisc %p])\n", sch, p);
1da177e4
LT
403 qdisc_reset(p->q);
404 sch->q.qlen = 0;
405}
406
1da177e4
LT
407static void dsmark_destroy(struct Qdisc *sch)
408{
81da99ed 409 struct dsmark_qdisc_data *p = qdisc_priv(sch);
1da177e4 410
81da99ed 411 pr_debug("dsmark_destroy(sch %p,[qdisc %p])\n", sch, p);
af0d1141 412
ff31ab56 413 tcf_destroy_chain(&p->filter_list);
1da177e4
LT
414 qdisc_destroy(p->q);
415 kfree(p->mask);
416}
417
1da177e4 418static int dsmark_dump_class(struct Qdisc *sch, unsigned long cl,
02f23f09 419 struct sk_buff *skb, struct tcmsg *tcm)
1da177e4 420{
81da99ed 421 struct dsmark_qdisc_data *p = qdisc_priv(sch);
1e90474c 422 struct nlattr *opts = NULL;
1da177e4 423
81da99ed 424 pr_debug("dsmark_dump_class(sch %p,[qdisc %p],class %ld\n", sch, p, cl);
02f23f09
TG
425
426 if (!dsmark_valid_index(p, cl))
1da177e4 427 return -EINVAL;
02f23f09
TG
428
429 tcm->tcm_handle = TC_H_MAKE(TC_H_MAJ(sch->handle), cl-1);
cdc7f8e3 430 tcm->tcm_info = p->q->handle;
02f23f09 431
1e90474c
PM
432 opts = nla_nest_start(skb, TCA_OPTIONS);
433 if (opts == NULL)
434 goto nla_put_failure;
435 NLA_PUT_U8(skb, TCA_DSMARK_MASK, p->mask[cl-1]);
436 NLA_PUT_U8(skb, TCA_DSMARK_VALUE, p->value[cl-1]);
02f23f09 437
1e90474c 438 return nla_nest_end(skb, opts);
1da177e4 439
1e90474c 440nla_put_failure:
bc3ed28c
TG
441 nla_nest_cancel(skb, opts);
442 return -EMSGSIZE;
1da177e4
LT
443}
444
445static int dsmark_dump(struct Qdisc *sch, struct sk_buff *skb)
446{
81da99ed 447 struct dsmark_qdisc_data *p = qdisc_priv(sch);
1e90474c 448 struct nlattr *opts = NULL;
1da177e4 449
1e90474c
PM
450 opts = nla_nest_start(skb, TCA_OPTIONS);
451 if (opts == NULL)
452 goto nla_put_failure;
453 NLA_PUT_U16(skb, TCA_DSMARK_INDICES, p->indices);
02f23f09
TG
454
455 if (p->default_index != NO_DEFAULT_INDEX)
1e90474c 456 NLA_PUT_U16(skb, TCA_DSMARK_DEFAULT_INDEX, p->default_index);
1da177e4 457
1da177e4 458 if (p->set_tc_index)
1e90474c 459 NLA_PUT_FLAG(skb, TCA_DSMARK_SET_TC_INDEX);
02f23f09 460
1e90474c 461 return nla_nest_end(skb, opts);
1da177e4 462
1e90474c 463nla_put_failure:
bc3ed28c
TG
464 nla_nest_cancel(skb, opts);
465 return -EMSGSIZE;
1da177e4
LT
466}
467
20fea08b 468static const struct Qdisc_class_ops dsmark_class_ops = {
1da177e4
LT
469 .graft = dsmark_graft,
470 .leaf = dsmark_leaf,
471 .get = dsmark_get,
472 .put = dsmark_put,
473 .change = dsmark_change,
474 .delete = dsmark_delete,
475 .walk = dsmark_walk,
476 .tcf_chain = dsmark_find_tcf,
477 .bind_tcf = dsmark_bind_filter,
478 .unbind_tcf = dsmark_put,
479 .dump = dsmark_dump_class,
480};
481
20fea08b 482static struct Qdisc_ops dsmark_qdisc_ops __read_mostly = {
1da177e4
LT
483 .next = NULL,
484 .cl_ops = &dsmark_class_ops,
485 .id = "dsmark",
486 .priv_size = sizeof(struct dsmark_qdisc_data),
487 .enqueue = dsmark_enqueue,
488 .dequeue = dsmark_dequeue,
8e3af978 489 .peek = dsmark_peek,
1da177e4
LT
490 .drop = dsmark_drop,
491 .init = dsmark_init,
492 .reset = dsmark_reset,
493 .destroy = dsmark_destroy,
494 .change = NULL,
495 .dump = dsmark_dump,
496 .owner = THIS_MODULE,
497};
498
499static int __init dsmark_module_init(void)
500{
501 return register_qdisc(&dsmark_qdisc_ops);
502}
af0d1141 503
10297b99 504static void __exit dsmark_module_exit(void)
1da177e4
LT
505{
506 unregister_qdisc(&dsmark_qdisc_ops);
507}
af0d1141 508
1da177e4
LT
509module_init(dsmark_module_init)
510module_exit(dsmark_module_exit)
af0d1141 511
1da177e4 512MODULE_LICENSE("GPL");