Pull battery into release branch
[linux-2.6] / net / sched / sch_dsmark.c
1 /* net/sched/sch_dsmark.c - Differentiated Services field marker */
2
3 /* Written 1998-2000 by Werner Almesberger, EPFL ICA */
4
5
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>
12 #include <linux/rtnetlink.h>
13 #include <net/pkt_sched.h>
14 #include <net/dsfield.h>
15 #include <net/inet_ecn.h>
16 #include <asm/byteorder.h>
17
18
19 #if 0 /* control */
20 #define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
21 #else
22 #define DPRINTK(format,args...)
23 #endif
24
25 #if 0 /* data */
26 #define D2PRINTK(format,args...) printk(KERN_DEBUG format,##args)
27 #else
28 #define D2PRINTK(format,args...)
29 #endif
30
31
32 #define PRIV(sch) ((struct dsmark_qdisc_data *) qdisc_priv(sch))
33
34
35 /*
36  * classid      class           marking
37  * -------      -----           -------
38  *   n/a          0             n/a
39  *   x:0          1             use entry [0]
40  *   ...         ...            ...
41  *   x:y y>0     y+1            use entry [y]
42  *   ...         ...            ...
43  * x:indices-1  indices         use entry [indices-1]
44  *   ...         ...            ...
45  *   x:y         y+1            use entry [y & (indices-1)]
46  *   ...         ...            ...
47  * 0xffff       0x10000         use entry [indices-1]
48  */
49
50
51 #define NO_DEFAULT_INDEX        (1 << 16)
52
53 struct dsmark_qdisc_data {
54         struct Qdisc            *q;
55         struct tcf_proto        *filter_list;
56         u8                      *mask;  /* "owns" the array */
57         u8                      *value;
58         u16                     indices;
59         u32                     default_index;  /* index range is 0...0xffff */
60         int                     set_tc_index;
61 };
62
63 static inline int dsmark_valid_indices(u16 indices)
64 {
65         while (indices != 1) {
66                 if (indices & 1)
67                         return 0;
68                 indices >>= 1;
69         }
70
71         return 1;
72 }
73
74 static inline int dsmark_valid_index(struct dsmark_qdisc_data *p, u16 index)
75 {
76         return (index <= p->indices && index > 0);
77 }
78
79 /* ------------------------- Class/flow operations ------------------------- */
80
81 static int dsmark_graft(struct Qdisc *sch, unsigned long arg,
82                         struct Qdisc *new, struct Qdisc **old)
83 {
84         struct dsmark_qdisc_data *p = PRIV(sch);
85
86         DPRINTK("dsmark_graft(sch %p,[qdisc %p],new %p,old %p)\n",
87                 sch, p, new, old);
88
89         if (new == NULL) {
90                 new = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops,
91                                         sch->handle);
92                 if (new == NULL)
93                         new = &noop_qdisc;
94         }
95
96         sch_tree_lock(sch);
97         *old = xchg(&p->q, new);
98         qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
99         qdisc_reset(*old);
100         sch_tree_unlock(sch);
101
102         return 0;
103 }
104
105 static struct Qdisc *dsmark_leaf(struct Qdisc *sch, unsigned long arg)
106 {
107         return PRIV(sch)->q;
108 }
109
110 static unsigned long dsmark_get(struct Qdisc *sch, u32 classid)
111 {
112         DPRINTK("dsmark_get(sch %p,[qdisc %p],classid %x)\n",
113                 sch, PRIV(sch), classid);
114
115         return TC_H_MIN(classid) + 1;
116 }
117
118 static unsigned long dsmark_bind_filter(struct Qdisc *sch,
119                                         unsigned long parent, u32 classid)
120 {
121         return dsmark_get(sch, classid);
122 }
123
124 static void dsmark_put(struct Qdisc *sch, unsigned long cl)
125 {
126 }
127
128 static int dsmark_change(struct Qdisc *sch, u32 classid, u32 parent,
129                          struct rtattr **tca, unsigned long *arg)
130 {
131         struct dsmark_qdisc_data *p = PRIV(sch);
132         struct rtattr *opt = tca[TCA_OPTIONS-1];
133         struct rtattr *tb[TCA_DSMARK_MAX];
134         int err = -EINVAL;
135         u8 mask = 0;
136
137         DPRINTK("dsmark_change(sch %p,[qdisc %p],classid %x,parent %x),"
138                 "arg 0x%lx\n", sch, p, classid, parent, *arg);
139
140         if (!dsmark_valid_index(p, *arg)) {
141                 err = -ENOENT;
142                 goto rtattr_failure;
143         }
144
145         if (!opt || rtattr_parse_nested(tb, TCA_DSMARK_MAX, opt))
146                 goto rtattr_failure;
147
148         if (tb[TCA_DSMARK_MASK-1])
149                 mask = RTA_GET_U8(tb[TCA_DSMARK_MASK-1]);
150
151         if (tb[TCA_DSMARK_VALUE-1])
152                 p->value[*arg-1] = RTA_GET_U8(tb[TCA_DSMARK_VALUE-1]);
153
154         if (tb[TCA_DSMARK_MASK-1])
155                 p->mask[*arg-1] = mask;
156
157         err = 0;
158
159 rtattr_failure:
160         return err;
161 }
162
163 static int dsmark_delete(struct Qdisc *sch, unsigned long arg)
164 {
165         struct dsmark_qdisc_data *p = PRIV(sch);
166
167         if (!dsmark_valid_index(p, arg))
168                 return -EINVAL;
169
170         p->mask[arg-1] = 0xff;
171         p->value[arg-1] = 0;
172
173         return 0;
174 }
175
176 static void dsmark_walk(struct Qdisc *sch,struct qdisc_walker *walker)
177 {
178         struct dsmark_qdisc_data *p = PRIV(sch);
179         int i;
180
181         DPRINTK("dsmark_walk(sch %p,[qdisc %p],walker %p)\n", sch, p, walker);
182
183         if (walker->stop)
184                 return;
185
186         for (i = 0; i < p->indices; i++) {
187                 if (p->mask[i] == 0xff && !p->value[i])
188                         goto ignore;
189                 if (walker->count >= walker->skip) {
190                         if (walker->fn(sch, i+1, walker) < 0) {
191                                 walker->stop = 1;
192                                 break;
193                         }
194                 }
195 ignore:
196                 walker->count++;
197         }
198 }
199
200 static struct tcf_proto **dsmark_find_tcf(struct Qdisc *sch,unsigned long cl)
201 {
202         return &PRIV(sch)->filter_list;
203 }
204
205 /* --------------------------- Qdisc operations ---------------------------- */
206
207 static int dsmark_enqueue(struct sk_buff *skb,struct Qdisc *sch)
208 {
209         struct dsmark_qdisc_data *p = PRIV(sch);
210         int err;
211
212         D2PRINTK("dsmark_enqueue(skb %p,sch %p,[qdisc %p])\n", skb, sch, p);
213
214         if (p->set_tc_index) {
215                 /* FIXME: Safe with non-linear skbs? --RR */
216                 switch (skb->protocol) {
217                         case __constant_htons(ETH_P_IP):
218                                 skb->tc_index = ipv4_get_dsfield(ip_hdr(skb))
219                                         & ~INET_ECN_MASK;
220                                 break;
221                         case __constant_htons(ETH_P_IPV6):
222                                 skb->tc_index = ipv6_get_dsfield(ipv6_hdr(skb))
223                                         & ~INET_ECN_MASK;
224                                 break;
225                         default:
226                                 skb->tc_index = 0;
227                                 break;
228                 }
229         }
230
231         if (TC_H_MAJ(skb->priority) == sch->handle)
232                 skb->tc_index = TC_H_MIN(skb->priority);
233         else {
234                 struct tcf_result res;
235                 int result = tc_classify(skb, p->filter_list, &res);
236
237                 D2PRINTK("result %d class 0x%04x\n", result, res.classid);
238
239                 switch (result) {
240 #ifdef CONFIG_NET_CLS_ACT
241                 case TC_ACT_QUEUED:
242                 case TC_ACT_STOLEN:
243                         kfree_skb(skb);
244                         return NET_XMIT_SUCCESS;
245                 case TC_ACT_SHOT:
246                         kfree_skb(skb);
247                         sch->qstats.drops++;
248                         return NET_XMIT_BYPASS;
249 #endif
250                 case TC_ACT_OK:
251                         skb->tc_index = TC_H_MIN(res.classid);
252                         break;
253                 default:
254                         if (p->default_index != NO_DEFAULT_INDEX)
255                                 skb->tc_index = p->default_index;
256                         break;
257                 }
258         }
259
260         err = p->q->enqueue(skb,p->q);
261         if (err != NET_XMIT_SUCCESS) {
262                 sch->qstats.drops++;
263                 return err;
264         }
265
266         sch->bstats.bytes += skb->len;
267         sch->bstats.packets++;
268         sch->q.qlen++;
269
270         return NET_XMIT_SUCCESS;
271 }
272
273 static struct sk_buff *dsmark_dequeue(struct Qdisc *sch)
274 {
275         struct dsmark_qdisc_data *p = PRIV(sch);
276         struct sk_buff *skb;
277         u32 index;
278
279         D2PRINTK("dsmark_dequeue(sch %p,[qdisc %p])\n", sch, p);
280
281         skb = p->q->ops->dequeue(p->q);
282         if (skb == NULL)
283                 return NULL;
284
285         sch->q.qlen--;
286
287         index = skb->tc_index & (p->indices - 1);
288         D2PRINTK("index %d->%d\n", skb->tc_index, index);
289
290         switch (skb->protocol) {
291                 case __constant_htons(ETH_P_IP):
292                         ipv4_change_dsfield(ip_hdr(skb), p->mask[index],
293                                             p->value[index]);
294                         break;
295                 case __constant_htons(ETH_P_IPV6):
296                         ipv6_change_dsfield(ipv6_hdr(skb), p->mask[index],
297                                             p->value[index]);
298                         break;
299                 default:
300                         /*
301                          * Only complain if a change was actually attempted.
302                          * This way, we can send non-IP traffic through dsmark
303                          * and don't need yet another qdisc as a bypass.
304                          */
305                         if (p->mask[index] != 0xff || p->value[index])
306                                 printk(KERN_WARNING "dsmark_dequeue: "
307                                        "unsupported protocol %d\n",
308                                        ntohs(skb->protocol));
309                         break;
310         }
311
312         return skb;
313 }
314
315 static int dsmark_requeue(struct sk_buff *skb,struct Qdisc *sch)
316 {
317         struct dsmark_qdisc_data *p = PRIV(sch);
318         int err;
319
320         D2PRINTK("dsmark_requeue(skb %p,sch %p,[qdisc %p])\n", skb, sch, p);
321
322         err = p->q->ops->requeue(skb, p->q);
323         if (err != NET_XMIT_SUCCESS) {
324                 sch->qstats.drops++;
325                 return err;
326         }
327
328         sch->q.qlen++;
329         sch->qstats.requeues++;
330
331         return NET_XMIT_SUCCESS;
332 }
333
334 static unsigned int dsmark_drop(struct Qdisc *sch)
335 {
336         struct dsmark_qdisc_data *p = PRIV(sch);
337         unsigned int len;
338
339         DPRINTK("dsmark_reset(sch %p,[qdisc %p])\n", sch, p);
340
341         if (p->q->ops->drop == NULL)
342                 return 0;
343
344         len = p->q->ops->drop(p->q);
345         if (len)
346                 sch->q.qlen--;
347
348         return len;
349 }
350
351 static int dsmark_init(struct Qdisc *sch, struct rtattr *opt)
352 {
353         struct dsmark_qdisc_data *p = PRIV(sch);
354         struct rtattr *tb[TCA_DSMARK_MAX];
355         int err = -EINVAL;
356         u32 default_index = NO_DEFAULT_INDEX;
357         u16 indices;
358         u8 *mask;
359
360         DPRINTK("dsmark_init(sch %p,[qdisc %p],opt %p)\n", sch, p, opt);
361
362         if (!opt || rtattr_parse_nested(tb, TCA_DSMARK_MAX, opt) < 0)
363                 goto errout;
364
365         indices = RTA_GET_U16(tb[TCA_DSMARK_INDICES-1]);
366         if (!indices || !dsmark_valid_indices(indices))
367                 goto errout;
368
369         if (tb[TCA_DSMARK_DEFAULT_INDEX-1])
370                 default_index = RTA_GET_U16(tb[TCA_DSMARK_DEFAULT_INDEX-1]);
371
372         mask = kmalloc(indices * 2, GFP_KERNEL);
373         if (mask == NULL) {
374                 err = -ENOMEM;
375                 goto errout;
376         }
377
378         p->mask = mask;
379         memset(p->mask, 0xff, indices);
380
381         p->value = p->mask + indices;
382         memset(p->value, 0, indices);
383
384         p->indices = indices;
385         p->default_index = default_index;
386         p->set_tc_index = RTA_GET_FLAG(tb[TCA_DSMARK_SET_TC_INDEX-1]);
387
388         p->q = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops, sch->handle);
389         if (p->q == NULL)
390                 p->q = &noop_qdisc;
391
392         DPRINTK("dsmark_init: qdisc %p\n", p->q);
393
394         err = 0;
395 errout:
396 rtattr_failure:
397         return err;
398 }
399
400 static void dsmark_reset(struct Qdisc *sch)
401 {
402         struct dsmark_qdisc_data *p = PRIV(sch);
403
404         DPRINTK("dsmark_reset(sch %p,[qdisc %p])\n", sch, p);
405         qdisc_reset(p->q);
406         sch->q.qlen = 0;
407 }
408
409 static void dsmark_destroy(struct Qdisc *sch)
410 {
411         struct dsmark_qdisc_data *p = PRIV(sch);
412
413         DPRINTK("dsmark_destroy(sch %p,[qdisc %p])\n", sch, p);
414
415         tcf_destroy_chain(p->filter_list);
416         qdisc_destroy(p->q);
417         kfree(p->mask);
418 }
419
420 static int dsmark_dump_class(struct Qdisc *sch, unsigned long cl,
421                              struct sk_buff *skb, struct tcmsg *tcm)
422 {
423         struct dsmark_qdisc_data *p = PRIV(sch);
424         struct rtattr *opts = NULL;
425
426         DPRINTK("dsmark_dump_class(sch %p,[qdisc %p],class %ld\n", sch, p, cl);
427
428         if (!dsmark_valid_index(p, cl))
429                 return -EINVAL;
430
431         tcm->tcm_handle = TC_H_MAKE(TC_H_MAJ(sch->handle), cl-1);
432         tcm->tcm_info = p->q->handle;
433
434         opts = RTA_NEST(skb, TCA_OPTIONS);
435         RTA_PUT_U8(skb,TCA_DSMARK_MASK, p->mask[cl-1]);
436         RTA_PUT_U8(skb,TCA_DSMARK_VALUE, p->value[cl-1]);
437
438         return RTA_NEST_END(skb, opts);
439
440 rtattr_failure:
441         return RTA_NEST_CANCEL(skb, opts);
442 }
443
444 static int dsmark_dump(struct Qdisc *sch, struct sk_buff *skb)
445 {
446         struct dsmark_qdisc_data *p = PRIV(sch);
447         struct rtattr *opts = NULL;
448
449         opts = RTA_NEST(skb, TCA_OPTIONS);
450         RTA_PUT_U16(skb, TCA_DSMARK_INDICES, p->indices);
451
452         if (p->default_index != NO_DEFAULT_INDEX)
453                 RTA_PUT_U16(skb, TCA_DSMARK_DEFAULT_INDEX, p->default_index);
454
455         if (p->set_tc_index)
456                 RTA_PUT_FLAG(skb, TCA_DSMARK_SET_TC_INDEX);
457
458         return RTA_NEST_END(skb, opts);
459
460 rtattr_failure:
461         return RTA_NEST_CANCEL(skb, opts);
462 }
463
464 static struct Qdisc_class_ops dsmark_class_ops = {
465         .graft          =       dsmark_graft,
466         .leaf           =       dsmark_leaf,
467         .get            =       dsmark_get,
468         .put            =       dsmark_put,
469         .change         =       dsmark_change,
470         .delete         =       dsmark_delete,
471         .walk           =       dsmark_walk,
472         .tcf_chain      =       dsmark_find_tcf,
473         .bind_tcf       =       dsmark_bind_filter,
474         .unbind_tcf     =       dsmark_put,
475         .dump           =       dsmark_dump_class,
476 };
477
478 static struct Qdisc_ops dsmark_qdisc_ops = {
479         .next           =       NULL,
480         .cl_ops         =       &dsmark_class_ops,
481         .id             =       "dsmark",
482         .priv_size      =       sizeof(struct dsmark_qdisc_data),
483         .enqueue        =       dsmark_enqueue,
484         .dequeue        =       dsmark_dequeue,
485         .requeue        =       dsmark_requeue,
486         .drop           =       dsmark_drop,
487         .init           =       dsmark_init,
488         .reset          =       dsmark_reset,
489         .destroy        =       dsmark_destroy,
490         .change         =       NULL,
491         .dump           =       dsmark_dump,
492         .owner          =       THIS_MODULE,
493 };
494
495 static int __init dsmark_module_init(void)
496 {
497         return register_qdisc(&dsmark_qdisc_ops);
498 }
499
500 static void __exit dsmark_module_exit(void)
501 {
502         unregister_qdisc(&dsmark_qdisc_ops);
503 }
504
505 module_init(dsmark_module_init)
506 module_exit(dsmark_module_exit)
507
508 MODULE_LICENSE("GPL");