microblaze: uaccess: fix put_user and get_user macros
[linux-2.6.git] / 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 <linux/bitops.h>
14 #include <net/pkt_sched.h>
15 #include <net/dsfield.h>
16 #include <net/inet_ecn.h>
17 #include <asm/byteorder.h>
18
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
37 struct dsmark_qdisc_data {
38         struct Qdisc            *q;
39         struct tcf_proto        *filter_list;
40         u8                      *mask;  /* "owns" the array */
41         u8                      *value;
42         u16                     indices;
43         u32                     default_index;  /* index range is 0...0xffff */
44         int                     set_tc_index;
45 };
46
47 static inline int dsmark_valid_index(struct dsmark_qdisc_data *p, u16 index)
48 {
49         return (index <= p->indices && index > 0);
50 }
51
52 /* ------------------------- Class/flow operations ------------------------- */
53
54 static int dsmark_graft(struct Qdisc *sch, unsigned long arg,
55                         struct Qdisc *new, struct Qdisc **old)
56 {
57         struct dsmark_qdisc_data *p = qdisc_priv(sch);
58
59         pr_debug("dsmark_graft(sch %p,[qdisc %p],new %p,old %p)\n",
60                 sch, p, new, old);
61
62         if (new == NULL) {
63                 new = qdisc_create_dflt(qdisc_dev(sch), sch->dev_queue,
64                                         &pfifo_qdisc_ops,
65                                         sch->handle);
66                 if (new == NULL)
67                         new = &noop_qdisc;
68         }
69
70         sch_tree_lock(sch);
71         *old = p->q;
72         p->q = new;
73         qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
74         qdisc_reset(*old);
75         sch_tree_unlock(sch);
76
77         return 0;
78 }
79
80 static struct Qdisc *dsmark_leaf(struct Qdisc *sch, unsigned long arg)
81 {
82         struct dsmark_qdisc_data *p = qdisc_priv(sch);
83         return p->q;
84 }
85
86 static unsigned long dsmark_get(struct Qdisc *sch, u32 classid)
87 {
88         pr_debug("dsmark_get(sch %p,[qdisc %p],classid %x)\n",
89                 sch, qdisc_priv(sch), classid);
90
91         return TC_H_MIN(classid) + 1;
92 }
93
94 static unsigned long dsmark_bind_filter(struct Qdisc *sch,
95                                         unsigned long parent, u32 classid)
96 {
97         return dsmark_get(sch, classid);
98 }
99
100 static void dsmark_put(struct Qdisc *sch, unsigned long cl)
101 {
102 }
103
104 static 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
112 static int dsmark_change(struct Qdisc *sch, u32 classid, u32 parent,
113                          struct nlattr **tca, unsigned long *arg)
114 {
115         struct dsmark_qdisc_data *p = qdisc_priv(sch);
116         struct nlattr *opt = tca[TCA_OPTIONS];
117         struct nlattr *tb[TCA_DSMARK_MAX + 1];
118         int err = -EINVAL;
119         u8 mask = 0;
120
121         pr_debug("dsmark_change(sch %p,[qdisc %p],classid %x,parent %x),"
122                 "arg 0x%lx\n", sch, p, classid, parent, *arg);
123
124         if (!dsmark_valid_index(p, *arg)) {
125                 err = -ENOENT;
126                 goto errout;
127         }
128
129         if (!opt)
130                 goto errout;
131
132         err = nla_parse_nested(tb, TCA_DSMARK_MAX, opt, dsmark_policy);
133         if (err < 0)
134                 goto errout;
135
136         if (tb[TCA_DSMARK_MASK])
137                 mask = nla_get_u8(tb[TCA_DSMARK_MASK]);
138
139         if (tb[TCA_DSMARK_VALUE])
140                 p->value[*arg-1] = nla_get_u8(tb[TCA_DSMARK_VALUE]);
141
142         if (tb[TCA_DSMARK_MASK])
143                 p->mask[*arg-1] = mask;
144
145         err = 0;
146
147 errout:
148         return err;
149 }
150
151 static int dsmark_delete(struct Qdisc *sch, unsigned long arg)
152 {
153         struct dsmark_qdisc_data *p = qdisc_priv(sch);
154
155         if (!dsmark_valid_index(p, arg))
156                 return -EINVAL;
157
158         p->mask[arg-1] = 0xff;
159         p->value[arg-1] = 0;
160
161         return 0;
162 }
163
164 static void dsmark_walk(struct Qdisc *sch, struct qdisc_walker *walker)
165 {
166         struct dsmark_qdisc_data *p = qdisc_priv(sch);
167         int i;
168
169         pr_debug("dsmark_walk(sch %p,[qdisc %p],walker %p)\n", sch, p, walker);
170
171         if (walker->stop)
172                 return;
173
174         for (i = 0; i < p->indices; i++) {
175                 if (p->mask[i] == 0xff && !p->value[i])
176                         goto ignore;
177                 if (walker->count >= walker->skip) {
178                         if (walker->fn(sch, i+1, walker) < 0) {
179                                 walker->stop = 1;
180                                 break;
181                         }
182                 }
183 ignore:
184                 walker->count++;
185         }
186 }
187
188 static inline struct tcf_proto **dsmark_find_tcf(struct Qdisc *sch,
189                                                  unsigned long cl)
190 {
191         struct dsmark_qdisc_data *p = qdisc_priv(sch);
192         return &p->filter_list;
193 }
194
195 /* --------------------------- Qdisc operations ---------------------------- */
196
197 static int dsmark_enqueue(struct sk_buff *skb, struct Qdisc *sch)
198 {
199         struct dsmark_qdisc_data *p = qdisc_priv(sch);
200         int err;
201
202         pr_debug("dsmark_enqueue(skb %p,sch %p,[qdisc %p])\n", skb, sch, p);
203
204         if (p->set_tc_index) {
205                 switch (skb->protocol) {
206                 case htons(ETH_P_IP):
207                         if (skb_cow_head(skb, sizeof(struct iphdr)))
208                                 goto drop;
209
210                         skb->tc_index = ipv4_get_dsfield(ip_hdr(skb))
211                                 & ~INET_ECN_MASK;
212                         break;
213
214                 case htons(ETH_P_IPV6):
215                         if (skb_cow_head(skb, sizeof(struct ipv6hdr)))
216                                 goto drop;
217
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;
224                 }
225         }
226
227         if (TC_H_MAJ(skb->priority) == sch->handle)
228                 skb->tc_index = TC_H_MIN(skb->priority);
229         else {
230                 struct tcf_result res;
231                 int result = tc_classify(skb, p->filter_list, &res);
232
233                 pr_debug("result %d class 0x%04x\n", result, res.classid);
234
235                 switch (result) {
236 #ifdef CONFIG_NET_CLS_ACT
237                 case TC_ACT_QUEUED:
238                 case TC_ACT_STOLEN:
239                         kfree_skb(skb);
240                         return NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
241
242                 case TC_ACT_SHOT:
243                         goto drop;
244 #endif
245                 case TC_ACT_OK:
246                         skb->tc_index = TC_H_MIN(res.classid);
247                         break;
248
249                 default:
250                         if (p->default_index != NO_DEFAULT_INDEX)
251                                 skb->tc_index = p->default_index;
252                         break;
253                 }
254         }
255
256         err = qdisc_enqueue(skb, p->q);
257         if (err != NET_XMIT_SUCCESS) {
258                 if (net_xmit_drop_count(err))
259                         sch->qstats.drops++;
260                 return err;
261         }
262
263         sch->bstats.bytes += qdisc_pkt_len(skb);
264         sch->bstats.packets++;
265         sch->q.qlen++;
266
267         return NET_XMIT_SUCCESS;
268
269 drop:
270         kfree_skb(skb);
271         sch->qstats.drops++;
272         return NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
273 }
274
275 static struct sk_buff *dsmark_dequeue(struct Qdisc *sch)
276 {
277         struct dsmark_qdisc_data *p = qdisc_priv(sch);
278         struct sk_buff *skb;
279         u32 index;
280
281         pr_debug("dsmark_dequeue(sch %p,[qdisc %p])\n", sch, p);
282
283         skb = p->q->ops->dequeue(p->q);
284         if (skb == NULL)
285                 return NULL;
286
287         sch->q.qlen--;
288
289         index = skb->tc_index & (p->indices - 1);
290         pr_debug("index %d->%d\n", skb->tc_index, index);
291
292         switch (skb->protocol) {
293         case htons(ETH_P_IP):
294                 ipv4_change_dsfield(ip_hdr(skb), p->mask[index],
295                                     p->value[index]);
296                         break;
297         case htons(ETH_P_IPV6):
298                 ipv6_change_dsfield(ipv6_hdr(skb), p->mask[index],
299                                     p->value[index]);
300                         break;
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;
312         }
313
314         return skb;
315 }
316
317 static 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
326 static unsigned int dsmark_drop(struct Qdisc *sch)
327 {
328         struct dsmark_qdisc_data *p = qdisc_priv(sch);
329         unsigned int len;
330
331         pr_debug("dsmark_reset(sch %p,[qdisc %p])\n", sch, p);
332
333         if (p->q->ops->drop == NULL)
334                 return 0;
335
336         len = p->q->ops->drop(p->q);
337         if (len)
338                 sch->q.qlen--;
339
340         return len;
341 }
342
343 static int dsmark_init(struct Qdisc *sch, struct nlattr *opt)
344 {
345         struct dsmark_qdisc_data *p = qdisc_priv(sch);
346         struct nlattr *tb[TCA_DSMARK_MAX + 1];
347         int err = -EINVAL;
348         u32 default_index = NO_DEFAULT_INDEX;
349         u16 indices;
350         u8 *mask;
351
352         pr_debug("dsmark_init(sch %p,[qdisc %p],opt %p)\n", sch, p, opt);
353
354         if (!opt)
355                 goto errout;
356
357         err = nla_parse_nested(tb, TCA_DSMARK_MAX, opt, dsmark_policy);
358         if (err < 0)
359                 goto errout;
360
361         err = -EINVAL;
362         indices = nla_get_u16(tb[TCA_DSMARK_INDICES]);
363
364         if (hweight32(indices) != 1)
365                 goto errout;
366
367         if (tb[TCA_DSMARK_DEFAULT_INDEX])
368                 default_index = nla_get_u16(tb[TCA_DSMARK_DEFAULT_INDEX]);
369
370         mask = kmalloc(indices * 2, GFP_KERNEL);
371         if (mask == NULL) {
372                 err = -ENOMEM;
373                 goto errout;
374         }
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;
384         p->set_tc_index = nla_get_flag(tb[TCA_DSMARK_SET_TC_INDEX]);
385
386         p->q = qdisc_create_dflt(qdisc_dev(sch), sch->dev_queue,
387                                  &pfifo_qdisc_ops, sch->handle);
388         if (p->q == NULL)
389                 p->q = &noop_qdisc;
390
391         pr_debug("dsmark_init: qdisc %p\n", p->q);
392
393         err = 0;
394 errout:
395         return err;
396 }
397
398 static void dsmark_reset(struct Qdisc *sch)
399 {
400         struct dsmark_qdisc_data *p = qdisc_priv(sch);
401
402         pr_debug("dsmark_reset(sch %p,[qdisc %p])\n", sch, p);
403         qdisc_reset(p->q);
404         sch->q.qlen = 0;
405 }
406
407 static void dsmark_destroy(struct Qdisc *sch)
408 {
409         struct dsmark_qdisc_data *p = qdisc_priv(sch);
410
411         pr_debug("dsmark_destroy(sch %p,[qdisc %p])\n", sch, p);
412
413         tcf_destroy_chain(&p->filter_list);
414         qdisc_destroy(p->q);
415         kfree(p->mask);
416 }
417
418 static int dsmark_dump_class(struct Qdisc *sch, unsigned long cl,
419                              struct sk_buff *skb, struct tcmsg *tcm)
420 {
421         struct dsmark_qdisc_data *p = qdisc_priv(sch);
422         struct nlattr *opts = NULL;
423
424         pr_debug("dsmark_dump_class(sch %p,[qdisc %p],class %ld\n", sch, p, cl);
425
426         if (!dsmark_valid_index(p, cl))
427                 return -EINVAL;
428
429         tcm->tcm_handle = TC_H_MAKE(TC_H_MAJ(sch->handle), cl-1);
430         tcm->tcm_info = p->q->handle;
431
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]);
437
438         return nla_nest_end(skb, opts);
439
440 nla_put_failure:
441         nla_nest_cancel(skb, opts);
442         return -EMSGSIZE;
443 }
444
445 static int dsmark_dump(struct Qdisc *sch, struct sk_buff *skb)
446 {
447         struct dsmark_qdisc_data *p = qdisc_priv(sch);
448         struct nlattr *opts = NULL;
449
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);
454
455         if (p->default_index != NO_DEFAULT_INDEX)
456                 NLA_PUT_U16(skb, TCA_DSMARK_DEFAULT_INDEX, p->default_index);
457
458         if (p->set_tc_index)
459                 NLA_PUT_FLAG(skb, TCA_DSMARK_SET_TC_INDEX);
460
461         return nla_nest_end(skb, opts);
462
463 nla_put_failure:
464         nla_nest_cancel(skb, opts);
465         return -EMSGSIZE;
466 }
467
468 static const struct Qdisc_class_ops dsmark_class_ops = {
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
482 static struct Qdisc_ops dsmark_qdisc_ops __read_mostly = {
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,
489         .peek           =       dsmark_peek,
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
499 static int __init dsmark_module_init(void)
500 {
501         return register_qdisc(&dsmark_qdisc_ops);
502 }
503
504 static void __exit dsmark_module_exit(void)
505 {
506         unregister_qdisc(&dsmark_qdisc_ops);
507 }
508
509 module_init(dsmark_module_init)
510 module_exit(dsmark_module_exit)
511
512 MODULE_LICENSE("GPL");