Automatic merge of /spare/repo/netdev-2.6 branch hdlc
[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/config.h>
7 #include <linux/module.h>
8 #include <linux/init.h>
9 #include <linux/types.h>
10 #include <linux/string.h>
11 #include <linux/errno.h>
12 #include <linux/skbuff.h>
13 #include <linux/netdevice.h> /* for pkt_sched */
14 #include <linux/rtnetlink.h>
15 #include <net/pkt_sched.h>
16 #include <net/dsfield.h>
17 #include <net/inet_ecn.h>
18 #include <asm/byteorder.h>
19
20
21 #if 0 /* control */
22 #define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
23 #else
24 #define DPRINTK(format,args...)
25 #endif
26
27 #if 0 /* data */
28 #define D2PRINTK(format,args...) printk(KERN_DEBUG format,##args)
29 #else
30 #define D2PRINTK(format,args...)
31 #endif
32
33
34 #define PRIV(sch) qdisc_priv(sch)
35
36
37 /*
38  * classid      class           marking
39  * -------      -----           -------
40  *   n/a          0             n/a
41  *   x:0          1             use entry [0]
42  *   ...         ...            ...
43  *   x:y y>0     y+1            use entry [y]
44  *   ...         ...            ...
45  * x:indices-1  indices         use entry [indices-1]
46  *   ...         ...            ...
47  *   x:y         y+1            use entry [y & (indices-1)]
48  *   ...         ...            ...
49  * 0xffff       0x10000         use entry [indices-1]
50  */
51
52
53 #define NO_DEFAULT_INDEX        (1 << 16)
54
55 struct dsmark_qdisc_data {
56         struct Qdisc            *q;
57         struct tcf_proto        *filter_list;
58         __u8                    *mask;  /* "owns" the array */
59         __u8                    *value;
60         __u16                   indices;
61         __u32                   default_index;  /* index range is 0...0xffff */
62         int                     set_tc_index;
63 };
64
65
66 /* ------------------------- Class/flow operations ------------------------- */
67
68
69 static int dsmark_graft(struct Qdisc *sch,unsigned long arg,
70     struct Qdisc *new,struct Qdisc **old)
71 {
72         struct dsmark_qdisc_data *p = PRIV(sch);
73
74         DPRINTK("dsmark_graft(sch %p,[qdisc %p],new %p,old %p)\n",sch,p,new,
75             old);
76
77         if (new == NULL) {
78                 new = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops);
79                 if (new == NULL)
80                         new = &noop_qdisc;
81         }
82
83         sch_tree_lock(sch);
84         *old = xchg(&p->q,new);
85         if (*old)
86                 qdisc_reset(*old);
87         sch->q.qlen = 0;
88         sch_tree_unlock(sch); /* @@@ move up ? */
89         return 0;
90 }
91
92
93 static struct Qdisc *dsmark_leaf(struct Qdisc *sch, unsigned long arg)
94 {
95         struct dsmark_qdisc_data *p = PRIV(sch);
96
97         return p->q;
98 }
99
100
101 static unsigned long dsmark_get(struct Qdisc *sch,u32 classid)
102 {
103         struct dsmark_qdisc_data *p __attribute__((unused)) = PRIV(sch);
104
105         DPRINTK("dsmark_get(sch %p,[qdisc %p],classid %x)\n",sch,p,classid);
106         return TC_H_MIN(classid)+1;
107 }
108
109
110 static unsigned long dsmark_bind_filter(struct Qdisc *sch,
111     unsigned long parent, u32 classid)
112 {
113         return dsmark_get(sch,classid);
114 }
115
116
117 static void dsmark_put(struct Qdisc *sch, unsigned long cl)
118 {
119 }
120
121
122 static int dsmark_change(struct Qdisc *sch, u32 classid, u32 parent,
123     struct rtattr **tca, unsigned long *arg)
124 {
125         struct dsmark_qdisc_data *p = PRIV(sch);
126         struct rtattr *opt = tca[TCA_OPTIONS-1];
127         struct rtattr *tb[TCA_DSMARK_MAX];
128
129         DPRINTK("dsmark_change(sch %p,[qdisc %p],classid %x,parent %x),"
130             "arg 0x%lx\n",sch,p,classid,parent,*arg);
131         if (*arg > p->indices)
132                 return -ENOENT;
133         if (!opt || rtattr_parse_nested(tb, TCA_DSMARK_MAX, opt))
134                 return -EINVAL;
135         if (tb[TCA_DSMARK_MASK-1]) {
136                 if (!RTA_PAYLOAD(tb[TCA_DSMARK_MASK-1]))
137                         return -EINVAL;
138                 p->mask[*arg-1] = *(__u8 *) RTA_DATA(tb[TCA_DSMARK_MASK-1]);
139         }
140         if (tb[TCA_DSMARK_VALUE-1]) {
141                 if (!RTA_PAYLOAD(tb[TCA_DSMARK_VALUE-1]))
142                         return -EINVAL;
143                 p->value[*arg-1] = *(__u8 *) RTA_DATA(tb[TCA_DSMARK_VALUE-1]);
144         }
145         return 0;
146 }
147
148
149 static int dsmark_delete(struct Qdisc *sch,unsigned long arg)
150 {
151         struct dsmark_qdisc_data *p = PRIV(sch);
152
153         if (!arg || arg > p->indices)
154                 return -EINVAL;
155         p->mask[arg-1] = 0xff;
156         p->value[arg-1] = 0;
157         return 0;
158 }
159
160
161 static void dsmark_walk(struct Qdisc *sch,struct qdisc_walker *walker)
162 {
163         struct dsmark_qdisc_data *p = PRIV(sch);
164         int i;
165
166         DPRINTK("dsmark_walk(sch %p,[qdisc %p],walker %p)\n",sch,p,walker);
167         if (walker->stop)
168                 return;
169         for (i = 0; i < p->indices; i++) {
170                 if (p->mask[i] == 0xff && !p->value[i])
171                         goto ignore;
172                 if (walker->count >= walker->skip) {
173                         if (walker->fn(sch, i+1, walker) < 0) {
174                                 walker->stop = 1;
175                                 break;
176                         }
177                 }
178 ignore:         
179                 walker->count++;
180         }
181 }
182
183
184 static struct tcf_proto **dsmark_find_tcf(struct Qdisc *sch,unsigned long cl)
185 {
186         struct dsmark_qdisc_data *p = PRIV(sch);
187
188         return &p->filter_list;
189 }
190
191
192 /* --------------------------- Qdisc operations ---------------------------- */
193
194
195 static int dsmark_enqueue(struct sk_buff *skb,struct Qdisc *sch)
196 {
197         struct dsmark_qdisc_data *p = PRIV(sch);
198         struct tcf_result res;
199         int result;
200         int ret = NET_XMIT_POLICED;
201
202         D2PRINTK("dsmark_enqueue(skb %p,sch %p,[qdisc %p])\n",skb,sch,p);
203         if (p->set_tc_index) {
204                 /* FIXME: Safe with non-linear skbs? --RR */
205                 switch (skb->protocol) {
206                         case __constant_htons(ETH_P_IP):
207                                 skb->tc_index = ipv4_get_dsfield(skb->nh.iph)
208                                         & ~INET_ECN_MASK;
209                                 break;
210                         case __constant_htons(ETH_P_IPV6):
211                                 skb->tc_index = ipv6_get_dsfield(skb->nh.ipv6h)
212                                         & ~INET_ECN_MASK;
213                                 break;
214                         default:
215                                 skb->tc_index = 0;
216                                 break;
217                 };
218         }
219         result = TC_POLICE_OK; /* be nice to gcc */
220         if (TC_H_MAJ(skb->priority) == sch->handle) {
221                 skb->tc_index = TC_H_MIN(skb->priority);
222         } else {
223                 result = tc_classify(skb,p->filter_list,&res);
224                 D2PRINTK("result %d class 0x%04x\n",result,res.classid);
225                 switch (result) {
226 #ifdef CONFIG_NET_CLS_POLICE
227                         case TC_POLICE_SHOT:
228                                 kfree_skb(skb);
229                                 break;
230 #if 0
231                         case TC_POLICE_RECLASSIFY:
232                                 /* FIXME: what to do here ??? */
233 #endif
234 #endif
235                         case TC_POLICE_OK:
236                                 skb->tc_index = TC_H_MIN(res.classid);
237                                 break;
238                         case TC_POLICE_UNSPEC:
239                                 /* fall through */
240                         default:
241                                 if (p->default_index != NO_DEFAULT_INDEX)
242                                         skb->tc_index = p->default_index;
243                                 break;
244                 };
245         }
246         if (
247 #ifdef CONFIG_NET_CLS_POLICE
248             result == TC_POLICE_SHOT ||
249 #endif
250
251             ((ret = p->q->enqueue(skb,p->q)) != 0)) {
252                 sch->qstats.drops++;
253                 return ret;
254         }
255         sch->bstats.bytes += skb->len;
256         sch->bstats.packets++;
257         sch->q.qlen++;
258         return ret;
259 }
260
261
262 static struct sk_buff *dsmark_dequeue(struct Qdisc *sch)
263 {
264         struct dsmark_qdisc_data *p = PRIV(sch);
265         struct sk_buff *skb;
266         int index;
267
268         D2PRINTK("dsmark_dequeue(sch %p,[qdisc %p])\n",sch,p);
269         skb = p->q->ops->dequeue(p->q);
270         if (!skb)
271                 return NULL;
272         sch->q.qlen--;
273         index = skb->tc_index & (p->indices-1);
274         D2PRINTK("index %d->%d\n",skb->tc_index,index);
275         switch (skb->protocol) {
276                 case __constant_htons(ETH_P_IP):
277                         ipv4_change_dsfield(skb->nh.iph,
278                             p->mask[index],p->value[index]);
279                         break;
280                 case __constant_htons(ETH_P_IPV6):
281                         ipv6_change_dsfield(skb->nh.ipv6h,
282                             p->mask[index],p->value[index]);
283                         break;
284                 default:
285                         /*
286                          * Only complain if a change was actually attempted.
287                          * This way, we can send non-IP traffic through dsmark
288                          * and don't need yet another qdisc as a bypass.
289                          */
290                         if (p->mask[index] != 0xff || p->value[index])
291                                 printk(KERN_WARNING "dsmark_dequeue: "
292                                        "unsupported protocol %d\n",
293                                        htons(skb->protocol));
294                         break;
295         };
296         return skb;
297 }
298
299
300 static int dsmark_requeue(struct sk_buff *skb,struct Qdisc *sch)
301 {
302         int ret;
303         struct dsmark_qdisc_data *p = PRIV(sch);
304
305         D2PRINTK("dsmark_requeue(skb %p,sch %p,[qdisc %p])\n",skb,sch,p);
306         if ((ret = p->q->ops->requeue(skb, p->q)) == 0) {
307                 sch->q.qlen++;
308                 sch->qstats.requeues++;
309                 return 0;
310         }
311         sch->qstats.drops++;
312         return ret;
313 }
314
315
316 static unsigned int dsmark_drop(struct Qdisc *sch)
317 {
318         struct dsmark_qdisc_data *p = PRIV(sch);
319         unsigned int len;
320         
321         DPRINTK("dsmark_reset(sch %p,[qdisc %p])\n",sch,p);
322         if (!p->q->ops->drop)
323                 return 0;
324         if (!(len = p->q->ops->drop(p->q)))
325                 return 0;
326         sch->q.qlen--;
327         return len;
328 }
329
330
331 static int dsmark_init(struct Qdisc *sch,struct rtattr *opt)
332 {
333         struct dsmark_qdisc_data *p = PRIV(sch);
334         struct rtattr *tb[TCA_DSMARK_MAX];
335         __u16 tmp;
336
337         DPRINTK("dsmark_init(sch %p,[qdisc %p],opt %p)\n",sch,p,opt);
338         if (!opt ||
339             rtattr_parse(tb,TCA_DSMARK_MAX,RTA_DATA(opt),RTA_PAYLOAD(opt)) < 0 ||
340             !tb[TCA_DSMARK_INDICES-1] ||
341             RTA_PAYLOAD(tb[TCA_DSMARK_INDICES-1]) < sizeof(__u16))
342                 return -EINVAL;
343         p->indices = *(__u16 *) RTA_DATA(tb[TCA_DSMARK_INDICES-1]);
344         if (!p->indices)
345                 return -EINVAL;
346         for (tmp = p->indices; tmp != 1; tmp >>= 1) {
347                 if (tmp & 1)
348                         return -EINVAL;
349         }
350         p->default_index = NO_DEFAULT_INDEX;
351         if (tb[TCA_DSMARK_DEFAULT_INDEX-1]) {
352                 if (RTA_PAYLOAD(tb[TCA_DSMARK_DEFAULT_INDEX-1]) < sizeof(__u16))
353                         return -EINVAL;
354                 p->default_index =
355                     *(__u16 *) RTA_DATA(tb[TCA_DSMARK_DEFAULT_INDEX-1]);
356         }
357         p->set_tc_index = !!tb[TCA_DSMARK_SET_TC_INDEX-1];
358         p->mask = kmalloc(p->indices*2,GFP_KERNEL);
359         if (!p->mask)
360                 return -ENOMEM;
361         p->value = p->mask+p->indices;
362         memset(p->mask,0xff,p->indices);
363         memset(p->value,0,p->indices);
364         if (!(p->q = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops)))
365                 p->q = &noop_qdisc;
366         DPRINTK("dsmark_init: qdisc %p\n",&p->q);
367         return 0;
368 }
369
370
371 static void dsmark_reset(struct Qdisc *sch)
372 {
373         struct dsmark_qdisc_data *p = PRIV(sch);
374
375         DPRINTK("dsmark_reset(sch %p,[qdisc %p])\n",sch,p);
376         qdisc_reset(p->q);
377         sch->q.qlen = 0;
378 }
379
380
381 static void dsmark_destroy(struct Qdisc *sch)
382 {
383         struct dsmark_qdisc_data *p = PRIV(sch);
384         struct tcf_proto *tp;
385
386         DPRINTK("dsmark_destroy(sch %p,[qdisc %p])\n",sch,p);
387         while (p->filter_list) {
388                 tp = p->filter_list;
389                 p->filter_list = tp->next;
390                 tcf_destroy(tp);
391         }
392         qdisc_destroy(p->q);
393         kfree(p->mask);
394 }
395
396
397 static int dsmark_dump_class(struct Qdisc *sch, unsigned long cl,
398     struct sk_buff *skb, struct tcmsg *tcm)
399 {
400         struct dsmark_qdisc_data *p = PRIV(sch);
401         unsigned char *b = skb->tail;
402         struct rtattr *rta;
403
404         DPRINTK("dsmark_dump_class(sch %p,[qdisc %p],class %ld\n",sch,p,cl);
405         if (!cl || cl > p->indices)
406                 return -EINVAL;
407         tcm->tcm_handle = TC_H_MAKE(TC_H_MAJ(sch->handle),cl-1);
408         rta = (struct rtattr *) b;
409         RTA_PUT(skb,TCA_OPTIONS,0,NULL);
410         RTA_PUT(skb,TCA_DSMARK_MASK,1,&p->mask[cl-1]);
411         RTA_PUT(skb,TCA_DSMARK_VALUE,1,&p->value[cl-1]);
412         rta->rta_len = skb->tail-b;
413         return skb->len;
414
415 rtattr_failure:
416         skb_trim(skb,b-skb->data);
417         return -1;
418 }
419
420 static int dsmark_dump(struct Qdisc *sch, struct sk_buff *skb)
421 {
422         struct dsmark_qdisc_data *p = PRIV(sch);
423         unsigned char *b = skb->tail;
424         struct rtattr *rta;
425
426         rta = (struct rtattr *) b;
427         RTA_PUT(skb,TCA_OPTIONS,0,NULL);
428         RTA_PUT(skb,TCA_DSMARK_INDICES,sizeof(__u16),&p->indices);
429         if (p->default_index != NO_DEFAULT_INDEX) {
430                 __u16 tmp = p->default_index;
431
432                 RTA_PUT(skb,TCA_DSMARK_DEFAULT_INDEX, sizeof(__u16), &tmp);
433         }
434         if (p->set_tc_index)
435                 RTA_PUT(skb, TCA_DSMARK_SET_TC_INDEX, 0, NULL);
436         rta->rta_len = skb->tail-b;
437         return skb->len;
438
439 rtattr_failure:
440         skb_trim(skb,b-skb->data);
441         return -1;
442 }
443
444 static struct Qdisc_class_ops dsmark_class_ops = {
445         .graft          =       dsmark_graft,
446         .leaf           =       dsmark_leaf,
447         .get            =       dsmark_get,
448         .put            =       dsmark_put,
449         .change         =       dsmark_change,
450         .delete         =       dsmark_delete,
451         .walk           =       dsmark_walk,
452         .tcf_chain      =       dsmark_find_tcf,
453         .bind_tcf       =       dsmark_bind_filter,
454         .unbind_tcf     =       dsmark_put,
455         .dump           =       dsmark_dump_class,
456 };
457
458 static struct Qdisc_ops dsmark_qdisc_ops = {
459         .next           =       NULL,
460         .cl_ops         =       &dsmark_class_ops,
461         .id             =       "dsmark",
462         .priv_size      =       sizeof(struct dsmark_qdisc_data),
463         .enqueue        =       dsmark_enqueue,
464         .dequeue        =       dsmark_dequeue,
465         .requeue        =       dsmark_requeue,
466         .drop           =       dsmark_drop,
467         .init           =       dsmark_init,
468         .reset          =       dsmark_reset,
469         .destroy        =       dsmark_destroy,
470         .change         =       NULL,
471         .dump           =       dsmark_dump,
472         .owner          =       THIS_MODULE,
473 };
474
475 static int __init dsmark_module_init(void)
476 {
477         return register_qdisc(&dsmark_qdisc_ops);
478 }
479 static void __exit dsmark_module_exit(void) 
480 {
481         unregister_qdisc(&dsmark_qdisc_ops);
482 }
483 module_init(dsmark_module_init)
484 module_exit(dsmark_module_exit)
485 MODULE_LICENSE("GPL");