]> bbs.cooldavid.org Git - net-next-2.6.git/blame - net/sched/cls_tcindex.c
[NETLINK]: Use nlmsg_trim() where appropriate
[net-next-2.6.git] / net / sched / cls_tcindex.c
CommitLineData
1da177e4
LT
1/*
2 * net/sched/cls_tcindex.c Packet classifier for skb->tc_index
3 *
4 * Written 1998,1999 by Werner Almesberger, EPFL ICA
5 */
6
1da177e4
LT
7#include <linux/module.h>
8#include <linux/types.h>
9#include <linux/kernel.h>
10#include <linux/skbuff.h>
11#include <linux/errno.h>
12#include <linux/netdevice.h>
13#include <net/ip.h>
14#include <net/act_api.h>
dc5fc579 15#include <net/netlink.h>
1da177e4
LT
16#include <net/pkt_cls.h>
17#include <net/route.h>
18
19
20/*
21 * Not quite sure if we need all the xchgs Alexey uses when accessing things.
22 * Can always add them later ... :)
23 */
24
25/*
26 * Passing parameters to the root seems to be done more awkwardly than really
27 * necessary. At least, u32 doesn't seem to use such dirty hacks. To be
28 * verified. FIXME.
29 */
30
31#define PERFECT_HASH_THRESHOLD 64 /* use perfect hash if not bigger */
32#define DEFAULT_HASH_SIZE 64 /* optimized for diffserv */
33
34
35#if 1 /* control */
36#define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
37#else
38#define DPRINTK(format,args...)
39#endif
40
41#if 0 /* data */
42#define D2PRINTK(format,args...) printk(KERN_DEBUG format,##args)
43#else
44#define D2PRINTK(format,args...)
45#endif
46
47
48#define PRIV(tp) ((struct tcindex_data *) (tp)->root)
49
50
51struct tcindex_filter_result {
52 struct tcf_exts exts;
53 struct tcf_result res;
54};
55
56struct tcindex_filter {
57 u16 key;
58 struct tcindex_filter_result result;
59 struct tcindex_filter *next;
60};
61
62
63struct tcindex_data {
64 struct tcindex_filter_result *perfect; /* perfect hash; NULL if none */
65 struct tcindex_filter **h; /* imperfect hash; only used if !perfect;
66 NULL if unused */
67 u16 mask; /* AND key with mask */
68 int shift; /* shift ANDed key to the right */
69 int hash; /* hash table size; 0 if undefined */
70 int alloc_hash; /* allocated size */
71 int fall_through; /* 0: only classify if explicit match */
72};
73
74static struct tcf_ext_map tcindex_ext_map = {
75 .police = TCA_TCINDEX_POLICE,
76 .action = TCA_TCINDEX_ACT
77};
78
79static inline int
80tcindex_filter_is_set(struct tcindex_filter_result *r)
81{
82 return tcf_exts_is_predicative(&r->exts) || r->res.classid;
83}
84
85static struct tcindex_filter_result *
86tcindex_lookup(struct tcindex_data *p, u16 key)
87{
88 struct tcindex_filter *f;
89
90 if (p->perfect)
91 return tcindex_filter_is_set(p->perfect + key) ?
92 p->perfect + key : NULL;
93 else if (p->h) {
94 for (f = p->h[key % p->hash]; f; f = f->next)
95 if (f->key == key)
96 return &f->result;
97 }
98
99 return NULL;
100}
101
102
103static int tcindex_classify(struct sk_buff *skb, struct tcf_proto *tp,
104 struct tcf_result *res)
105{
106 struct tcindex_data *p = PRIV(tp);
107 struct tcindex_filter_result *f;
108 int key = (skb->tc_index & p->mask) >> p->shift;
109
110 D2PRINTK("tcindex_classify(skb %p,tp %p,res %p),p %p\n",skb,tp,res,p);
111
112 f = tcindex_lookup(p, key);
113 if (!f) {
114 if (!p->fall_through)
115 return -1;
116 res->classid = TC_H_MAKE(TC_H_MAJ(tp->q->handle), key);
117 res->class = 0;
118 D2PRINTK("alg 0x%x\n",res->classid);
119 return 0;
120 }
121 *res = f->res;
122 D2PRINTK("map 0x%x\n",res->classid);
123
124 return tcf_exts_exec(skb, &f->exts, res);
125}
126
127
128static unsigned long tcindex_get(struct tcf_proto *tp, u32 handle)
129{
130 struct tcindex_data *p = PRIV(tp);
131 struct tcindex_filter_result *r;
132
133 DPRINTK("tcindex_get(tp %p,handle 0x%08x)\n",tp,handle);
134 if (p->perfect && handle >= p->alloc_hash)
135 return 0;
136 r = tcindex_lookup(p, handle);
137 return r && tcindex_filter_is_set(r) ? (unsigned long) r : 0UL;
138}
139
140
141static void tcindex_put(struct tcf_proto *tp, unsigned long f)
142{
143 DPRINTK("tcindex_put(tp %p,f 0x%lx)\n",tp,f);
144}
145
146
147static int tcindex_init(struct tcf_proto *tp)
148{
149 struct tcindex_data *p;
150
151 DPRINTK("tcindex_init(tp %p)\n",tp);
0da974f4 152 p = kzalloc(sizeof(struct tcindex_data),GFP_KERNEL);
1da177e4
LT
153 if (!p)
154 return -ENOMEM;
155
1da177e4
LT
156 p->mask = 0xffff;
157 p->hash = DEFAULT_HASH_SIZE;
158 p->fall_through = 1;
159
160 tp->root = p;
161 return 0;
162}
163
164
165static int
166__tcindex_delete(struct tcf_proto *tp, unsigned long arg, int lock)
167{
168 struct tcindex_data *p = PRIV(tp);
169 struct tcindex_filter_result *r = (struct tcindex_filter_result *) arg;
170 struct tcindex_filter *f = NULL;
171
172 DPRINTK("tcindex_delete(tp %p,arg 0x%lx),p %p,f %p\n",tp,arg,p,f);
173 if (p->perfect) {
174 if (!r->res.class)
175 return -ENOENT;
176 } else {
177 int i;
178 struct tcindex_filter **walk = NULL;
179
180 for (i = 0; i < p->hash; i++)
181 for (walk = p->h+i; *walk; walk = &(*walk)->next)
182 if (&(*walk)->result == r)
183 goto found;
184 return -ENOENT;
185
186found:
187 f = *walk;
188 if (lock)
189 tcf_tree_lock(tp);
190 *walk = f->next;
191 if (lock)
192 tcf_tree_unlock(tp);
193 }
194 tcf_unbind_filter(tp, &r->res);
195 tcf_exts_destroy(tp, &r->exts);
a51482bd 196 kfree(f);
1da177e4
LT
197 return 0;
198}
199
200static int tcindex_delete(struct tcf_proto *tp, unsigned long arg)
201{
202 return __tcindex_delete(tp, arg, 1);
203}
204
205static inline int
206valid_perfect_hash(struct tcindex_data *p)
207{
208 return p->hash > (p->mask >> p->shift);
209}
210
211static int
212tcindex_set_parms(struct tcf_proto *tp, unsigned long base, u32 handle,
213 struct tcindex_data *p, struct tcindex_filter_result *r,
214 struct rtattr **tb, struct rtattr *est)
215{
216 int err, balloc = 0;
217 struct tcindex_filter_result new_filter_result, *old_r = r;
218 struct tcindex_filter_result cr;
219 struct tcindex_data cp;
220 struct tcindex_filter *f = NULL; /* make gcc behave */
221 struct tcf_exts e;
222
223 err = tcf_exts_validate(tp, tb, est, &e, &tcindex_ext_map);
224 if (err < 0)
225 return err;
10297b99 226
1da177e4
LT
227 memcpy(&cp, p, sizeof(cp));
228 memset(&new_filter_result, 0, sizeof(new_filter_result));
229
230 if (old_r)
231 memcpy(&cr, r, sizeof(cr));
232 else
233 memset(&cr, 0, sizeof(cr));
234
235 err = -EINVAL;
236 if (tb[TCA_TCINDEX_HASH-1]) {
237 if (RTA_PAYLOAD(tb[TCA_TCINDEX_HASH-1]) < sizeof(u32))
238 goto errout;
239 cp.hash = *(u32 *) RTA_DATA(tb[TCA_TCINDEX_HASH-1]);
240 }
241
242 if (tb[TCA_TCINDEX_MASK-1]) {
243 if (RTA_PAYLOAD(tb[TCA_TCINDEX_MASK-1]) < sizeof(u16))
244 goto errout;
245 cp.mask = *(u16 *) RTA_DATA(tb[TCA_TCINDEX_MASK-1]);
246 }
247
248 if (tb[TCA_TCINDEX_SHIFT-1]) {
bb8a954f 249 if (RTA_PAYLOAD(tb[TCA_TCINDEX_SHIFT-1]) < sizeof(int))
1da177e4 250 goto errout;
bb8a954f 251 cp.shift = *(int *) RTA_DATA(tb[TCA_TCINDEX_SHIFT-1]);
1da177e4
LT
252 }
253
254 err = -EBUSY;
255 /* Hash already allocated, make sure that we still meet the
256 * requirements for the allocated hash.
257 */
258 if (cp.perfect) {
259 if (!valid_perfect_hash(&cp) ||
260 cp.hash > cp.alloc_hash)
261 goto errout;
262 } else if (cp.h && cp.hash != cp.alloc_hash)
263 goto errout;
264
265 err = -EINVAL;
266 if (tb[TCA_TCINDEX_FALL_THROUGH-1]) {
267 if (RTA_PAYLOAD(tb[TCA_TCINDEX_FALL_THROUGH-1]) < sizeof(u32))
268 goto errout;
269 cp.fall_through =
270 *(u32 *) RTA_DATA(tb[TCA_TCINDEX_FALL_THROUGH-1]);
271 }
272
273 if (!cp.hash) {
274 /* Hash not specified, use perfect hash if the upper limit
275 * of the hashing index is below the threshold.
276 */
277 if ((cp.mask >> cp.shift) < PERFECT_HASH_THRESHOLD)
278 cp.hash = (cp.mask >> cp.shift)+1;
279 else
280 cp.hash = DEFAULT_HASH_SIZE;
281 }
282
283 if (!cp.perfect && !cp.h)
284 cp.alloc_hash = cp.hash;
285
286 /* Note: this could be as restrictive as if (handle & ~(mask >> shift))
287 * but then, we'd fail handles that may become valid after some future
288 * mask change. While this is extremely unlikely to ever matter,
289 * the check below is safer (and also more backwards-compatible).
290 */
291 if (cp.perfect || valid_perfect_hash(&cp))
292 if (handle >= cp.alloc_hash)
293 goto errout;
294
295
296 err = -ENOMEM;
297 if (!cp.perfect && !cp.h) {
298 if (valid_perfect_hash(&cp)) {
0da974f4 299 cp.perfect = kcalloc(cp.hash, sizeof(*r), GFP_KERNEL);
1da177e4
LT
300 if (!cp.perfect)
301 goto errout;
1da177e4
LT
302 balloc = 1;
303 } else {
0da974f4 304 cp.h = kcalloc(cp.hash, sizeof(f), GFP_KERNEL);
1da177e4
LT
305 if (!cp.h)
306 goto errout;
1da177e4
LT
307 balloc = 2;
308 }
309 }
310
311 if (cp.perfect)
312 r = cp.perfect + handle;
313 else
314 r = tcindex_lookup(&cp, handle) ? : &new_filter_result;
315
316 if (r == &new_filter_result) {
0da974f4 317 f = kzalloc(sizeof(*f), GFP_KERNEL);
1da177e4
LT
318 if (!f)
319 goto errout_alloc;
10297b99 320 }
1da177e4
LT
321
322 if (tb[TCA_TCINDEX_CLASSID-1]) {
323 cr.res.classid = *(u32 *) RTA_DATA(tb[TCA_TCINDEX_CLASSID-1]);
324 tcf_bind_filter(tp, &cr.res, base);
10297b99 325 }
1da177e4
LT
326
327 tcf_exts_change(tp, &cr.exts, &e);
328
329 tcf_tree_lock(tp);
330 if (old_r && old_r != r)
331 memset(old_r, 0, sizeof(*old_r));
332
333 memcpy(p, &cp, sizeof(cp));
334 memcpy(r, &cr, sizeof(cr));
335
336 if (r == &new_filter_result) {
337 struct tcindex_filter **fp;
338
339 f->key = handle;
340 f->result = new_filter_result;
341 f->next = NULL;
342 for (fp = p->h+(handle % p->hash); *fp; fp = &(*fp)->next)
343 /* nothing */;
344 *fp = f;
10297b99 345 }
1da177e4
LT
346 tcf_tree_unlock(tp);
347
348 return 0;
349
350errout_alloc:
351 if (balloc == 1)
352 kfree(cp.perfect);
353 else if (balloc == 2)
354 kfree(cp.h);
355errout:
356 tcf_exts_destroy(tp, &e);
357 return err;
358}
359
360static int
361tcindex_change(struct tcf_proto *tp, unsigned long base, u32 handle,
362 struct rtattr **tca, unsigned long *arg)
363{
364 struct rtattr *opt = tca[TCA_OPTIONS-1];
365 struct rtattr *tb[TCA_TCINDEX_MAX];
366 struct tcindex_data *p = PRIV(tp);
367 struct tcindex_filter_result *r = (struct tcindex_filter_result *) *arg;
368
369 DPRINTK("tcindex_change(tp %p,handle 0x%08x,tca %p,arg %p),opt %p,"
370 "p %p,r %p,*arg 0x%lx\n",
371 tp, handle, tca, arg, opt, p, r, arg ? *arg : 0L);
372
373 if (!opt)
374 return 0;
375
376 if (rtattr_parse_nested(tb, TCA_TCINDEX_MAX, opt) < 0)
377 return -EINVAL;
378
379 return tcindex_set_parms(tp, base, handle, p, r, tb, tca[TCA_RATE-1]);
380}
381
382
383static void tcindex_walk(struct tcf_proto *tp, struct tcf_walker *walker)
384{
385 struct tcindex_data *p = PRIV(tp);
386 struct tcindex_filter *f,*next;
387 int i;
388
389 DPRINTK("tcindex_walk(tp %p,walker %p),p %p\n",tp,walker,p);
390 if (p->perfect) {
391 for (i = 0; i < p->hash; i++) {
392 if (!p->perfect[i].res.class)
393 continue;
394 if (walker->count >= walker->skip) {
395 if (walker->fn(tp,
396 (unsigned long) (p->perfect+i), walker)
397 < 0) {
398 walker->stop = 1;
399 return;
400 }
401 }
402 walker->count++;
403 }
404 }
405 if (!p->h)
406 return;
407 for (i = 0; i < p->hash; i++) {
408 for (f = p->h[i]; f; f = next) {
409 next = f->next;
410 if (walker->count >= walker->skip) {
411 if (walker->fn(tp,(unsigned long) &f->result,
412 walker) < 0) {
413 walker->stop = 1;
414 return;
415 }
416 }
417 walker->count++;
418 }
419 }
420}
421
422
423static int tcindex_destroy_element(struct tcf_proto *tp,
424 unsigned long arg, struct tcf_walker *walker)
425{
426 return __tcindex_delete(tp, arg, 0);
427}
428
429
430static void tcindex_destroy(struct tcf_proto *tp)
431{
432 struct tcindex_data *p = PRIV(tp);
433 struct tcf_walker walker;
434
435 DPRINTK("tcindex_destroy(tp %p),p %p\n",tp,p);
436 walker.count = 0;
437 walker.skip = 0;
438 walker.fn = &tcindex_destroy_element;
439 tcindex_walk(tp,&walker);
a51482bd
JJ
440 kfree(p->perfect);
441 kfree(p->h);
1da177e4
LT
442 kfree(p);
443 tp->root = NULL;
444}
445
446
447static int tcindex_dump(struct tcf_proto *tp, unsigned long fh,
448 struct sk_buff *skb, struct tcmsg *t)
449{
450 struct tcindex_data *p = PRIV(tp);
451 struct tcindex_filter_result *r = (struct tcindex_filter_result *) fh;
27a884dc 452 unsigned char *b = skb_tail_pointer(skb);
1da177e4
LT
453 struct rtattr *rta;
454
455 DPRINTK("tcindex_dump(tp %p,fh 0x%lx,skb %p,t %p),p %p,r %p,b %p\n",
456 tp,fh,skb,t,p,r,b);
457 DPRINTK("p->perfect %p p->h %p\n",p->perfect,p->h);
458 rta = (struct rtattr *) b;
459 RTA_PUT(skb,TCA_OPTIONS,0,NULL);
460 if (!fh) {
461 t->tcm_handle = ~0; /* whatever ... */
462 RTA_PUT(skb,TCA_TCINDEX_HASH,sizeof(p->hash),&p->hash);
463 RTA_PUT(skb,TCA_TCINDEX_MASK,sizeof(p->mask),&p->mask);
464 RTA_PUT(skb,TCA_TCINDEX_SHIFT,sizeof(p->shift),&p->shift);
465 RTA_PUT(skb,TCA_TCINDEX_FALL_THROUGH,sizeof(p->fall_through),
466 &p->fall_through);
27a884dc 467 rta->rta_len = skb_tail_pointer(skb) - b;
1da177e4
LT
468 } else {
469 if (p->perfect) {
470 t->tcm_handle = r-p->perfect;
471 } else {
472 struct tcindex_filter *f;
473 int i;
474
475 t->tcm_handle = 0;
476 for (i = 0; !t->tcm_handle && i < p->hash; i++) {
477 for (f = p->h[i]; !t->tcm_handle && f;
478 f = f->next) {
479 if (&f->result == r)
480 t->tcm_handle = f->key;
481 }
482 }
483 }
484 DPRINTK("handle = %d\n",t->tcm_handle);
485 if (r->res.class)
486 RTA_PUT(skb, TCA_TCINDEX_CLASSID, 4, &r->res.classid);
487
488 if (tcf_exts_dump(skb, &r->exts, &tcindex_ext_map) < 0)
489 goto rtattr_failure;
27a884dc 490 rta->rta_len = skb_tail_pointer(skb) - b;
1da177e4
LT
491
492 if (tcf_exts_dump_stats(skb, &r->exts, &tcindex_ext_map) < 0)
493 goto rtattr_failure;
494 }
10297b99 495
1da177e4
LT
496 return skb->len;
497
498rtattr_failure:
dc5fc579 499 nlmsg_trim(skb, b);
1da177e4
LT
500 return -1;
501}
502
503static struct tcf_proto_ops cls_tcindex_ops = {
504 .next = NULL,
505 .kind = "tcindex",
506 .classify = tcindex_classify,
507 .init = tcindex_init,
508 .destroy = tcindex_destroy,
509 .get = tcindex_get,
510 .put = tcindex_put,
511 .change = tcindex_change,
512 .delete = tcindex_delete,
513 .walk = tcindex_walk,
514 .dump = tcindex_dump,
515 .owner = THIS_MODULE,
516};
517
518static int __init init_tcindex(void)
519{
520 return register_tcf_proto_ops(&cls_tcindex_ops);
521}
522
10297b99 523static void __exit exit_tcindex(void)
1da177e4
LT
524{
525 unregister_tcf_proto_ops(&cls_tcindex_ops);
526}
527
528module_init(init_tcindex)
529module_exit(exit_tcindex)
530MODULE_LICENSE("GPL");