[PATCH] net: Add netconsole support to dm9000 driver
[linux-2.6] / net / sched / cls_basic.c
1 /*
2  * net/sched/cls_basic.c        Basic Packet Classifier.
3  *
4  *              This program is free software; you can redistribute it and/or
5  *              modify it under the terms of the GNU General Public License
6  *              as published by the Free Software Foundation; either version
7  *              2 of the License, or (at your option) any later version.
8  *
9  * Authors:     Thomas Graf <tgraf@suug.ch>
10  */
11
12 #include <linux/module.h>
13 #include <linux/types.h>
14 #include <linux/kernel.h>
15 #include <linux/sched.h>
16 #include <linux/string.h>
17 #include <linux/mm.h>
18 #include <linux/errno.h>
19 #include <linux/rtnetlink.h>
20 #include <linux/skbuff.h>
21 #include <net/act_api.h>
22 #include <net/pkt_cls.h>
23
24 struct basic_head
25 {
26         u32                     hgenerator;
27         struct list_head        flist;
28 };
29
30 struct basic_filter
31 {
32         u32                     handle;
33         struct tcf_exts         exts;
34         struct tcf_ematch_tree  ematches;
35         struct tcf_result       res;
36         struct list_head        link;
37 };
38
39 static struct tcf_ext_map basic_ext_map = {
40         .action = TCA_BASIC_ACT,
41         .police = TCA_BASIC_POLICE
42 };
43
44 static int basic_classify(struct sk_buff *skb, struct tcf_proto *tp,
45                           struct tcf_result *res)
46 {
47         int r;
48         struct basic_head *head = (struct basic_head *) tp->root;
49         struct basic_filter *f;
50
51         list_for_each_entry(f, &head->flist, link) {
52                 if (!tcf_em_tree_match(skb, &f->ematches, NULL))
53                         continue;
54                 *res = f->res;
55                 r = tcf_exts_exec(skb, &f->exts, res);
56                 if (r < 0)
57                         continue;
58                 return r;
59         }
60         return -1;
61 }
62
63 static unsigned long basic_get(struct tcf_proto *tp, u32 handle)
64 {
65         unsigned long l = 0UL;
66         struct basic_head *head = (struct basic_head *) tp->root;
67         struct basic_filter *f;
68
69         if (head == NULL)
70                 return 0UL;
71
72         list_for_each_entry(f, &head->flist, link)
73                 if (f->handle == handle)
74                         l = (unsigned long) f;
75
76         return l;
77 }
78
79 static void basic_put(struct tcf_proto *tp, unsigned long f)
80 {
81 }
82
83 static int basic_init(struct tcf_proto *tp)
84 {
85         return 0;
86 }
87
88 static inline void basic_delete_filter(struct tcf_proto *tp,
89                                        struct basic_filter *f)
90 {
91         tcf_unbind_filter(tp, &f->res);
92         tcf_exts_destroy(tp, &f->exts);
93         tcf_em_tree_destroy(tp, &f->ematches);
94         kfree(f);
95 }
96
97 static void basic_destroy(struct tcf_proto *tp)
98 {
99         struct basic_head *head = (struct basic_head *) xchg(&tp->root, NULL);
100         struct basic_filter *f, *n;
101         
102         list_for_each_entry_safe(f, n, &head->flist, link) {
103                 list_del(&f->link);
104                 basic_delete_filter(tp, f);
105         }
106 }
107
108 static int basic_delete(struct tcf_proto *tp, unsigned long arg)
109 {
110         struct basic_head *head = (struct basic_head *) tp->root;
111         struct basic_filter *t, *f = (struct basic_filter *) arg;
112
113         list_for_each_entry(t, &head->flist, link)
114                 if (t == f) {
115                         tcf_tree_lock(tp);
116                         list_del(&t->link);
117                         tcf_tree_unlock(tp);
118                         basic_delete_filter(tp, t);
119                         return 0;
120                 }
121
122         return -ENOENT;
123 }
124
125 static inline int basic_set_parms(struct tcf_proto *tp, struct basic_filter *f,
126                                   unsigned long base, struct rtattr **tb,
127                                   struct rtattr *est)
128 {
129         int err = -EINVAL;
130         struct tcf_exts e;
131         struct tcf_ematch_tree t;
132
133         if (tb[TCA_BASIC_CLASSID-1])
134                 if (RTA_PAYLOAD(tb[TCA_BASIC_CLASSID-1]) < sizeof(u32))
135                         return err;
136
137         err = tcf_exts_validate(tp, tb, est, &e, &basic_ext_map);
138         if (err < 0)
139                 return err;
140
141         err = tcf_em_tree_validate(tp, tb[TCA_BASIC_EMATCHES-1], &t);
142         if (err < 0)
143                 goto errout;
144
145         if (tb[TCA_BASIC_CLASSID-1]) {
146                 f->res.classid = *(u32*)RTA_DATA(tb[TCA_BASIC_CLASSID-1]);
147                 tcf_bind_filter(tp, &f->res, base);
148         }
149
150         tcf_exts_change(tp, &f->exts, &e);
151         tcf_em_tree_change(tp, &f->ematches, &t);
152
153         return 0;
154 errout:
155         tcf_exts_destroy(tp, &e);
156         return err;
157 }
158
159 static int basic_change(struct tcf_proto *tp, unsigned long base, u32 handle,
160                         struct rtattr **tca, unsigned long *arg)
161 {
162         int err = -EINVAL;
163         struct basic_head *head = (struct basic_head *) tp->root;
164         struct rtattr *tb[TCA_BASIC_MAX];
165         struct basic_filter *f = (struct basic_filter *) *arg;
166
167         if (tca[TCA_OPTIONS-1] == NULL)
168                 return -EINVAL;
169
170         if (rtattr_parse_nested(tb, TCA_BASIC_MAX, tca[TCA_OPTIONS-1]) < 0)
171                 return -EINVAL;
172
173         if (f != NULL) {
174                 if (handle && f->handle != handle)
175                         return -EINVAL;
176                 return basic_set_parms(tp, f, base, tb, tca[TCA_RATE-1]);
177         }
178
179         err = -ENOBUFS;
180         if (head == NULL) {
181                 head = kzalloc(sizeof(*head), GFP_KERNEL);
182                 if (head == NULL)
183                         goto errout;
184
185                 INIT_LIST_HEAD(&head->flist);
186                 tp->root = head;
187         }
188
189         f = kzalloc(sizeof(*f), GFP_KERNEL);
190         if (f == NULL)
191                 goto errout;
192
193         err = -EINVAL;
194         if (handle)
195                 f->handle = handle;
196         else {
197                 int i = 0x80000000;
198                 do {
199                         if (++head->hgenerator == 0x7FFFFFFF)
200                                 head->hgenerator = 1;
201                 } while (--i > 0 && basic_get(tp, head->hgenerator));
202
203                 if (i <= 0) {
204                         printk(KERN_ERR "Insufficient number of handles\n");
205                         goto errout;
206                 }
207
208                 f->handle = head->hgenerator;
209         }
210
211         err = basic_set_parms(tp, f, base, tb, tca[TCA_RATE-1]);
212         if (err < 0)
213                 goto errout;
214
215         tcf_tree_lock(tp);
216         list_add(&f->link, &head->flist);
217         tcf_tree_unlock(tp);
218         *arg = (unsigned long) f;
219
220         return 0;
221 errout:
222         if (*arg == 0UL && f)
223                 kfree(f);
224
225         return err;
226 }
227
228 static void basic_walk(struct tcf_proto *tp, struct tcf_walker *arg)
229 {
230         struct basic_head *head = (struct basic_head *) tp->root;
231         struct basic_filter *f;
232
233         list_for_each_entry(f, &head->flist, link) {
234                 if (arg->count < arg->skip)
235                         goto skip;
236
237                 if (arg->fn(tp, (unsigned long) f, arg) < 0) {
238                         arg->stop = 1;
239                         break;
240                 }
241 skip:
242                 arg->count++;
243         }
244 }
245
246 static int basic_dump(struct tcf_proto *tp, unsigned long fh,
247                       struct sk_buff *skb, struct tcmsg *t)
248 {
249         struct basic_filter *f = (struct basic_filter *) fh;
250         unsigned char *b = skb->tail;
251         struct rtattr *rta;
252
253         if (f == NULL)
254                 return skb->len;
255
256         t->tcm_handle = f->handle;
257
258         rta = (struct rtattr *) b;
259         RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
260
261         if (f->res.classid)
262                 RTA_PUT(skb, TCA_BASIC_CLASSID, sizeof(u32), &f->res.classid);
263
264         if (tcf_exts_dump(skb, &f->exts, &basic_ext_map) < 0 ||
265             tcf_em_tree_dump(skb, &f->ematches, TCA_BASIC_EMATCHES) < 0)
266                 goto rtattr_failure;
267
268         rta->rta_len = (skb->tail - b);
269         return skb->len;
270
271 rtattr_failure:
272         skb_trim(skb, b - skb->data);
273         return -1;
274 }
275
276 static struct tcf_proto_ops cls_basic_ops = {
277         .kind           =       "basic",
278         .classify       =       basic_classify,
279         .init           =       basic_init,
280         .destroy        =       basic_destroy,
281         .get            =       basic_get,
282         .put            =       basic_put,
283         .change         =       basic_change,
284         .delete         =       basic_delete,
285         .walk           =       basic_walk,
286         .dump           =       basic_dump,
287         .owner          =       THIS_MODULE,
288 };
289
290 static int __init init_basic(void)
291 {
292         return register_tcf_proto_ops(&cls_basic_ops);
293 }
294
295 static void __exit exit_basic(void) 
296 {
297         unregister_tcf_proto_ops(&cls_basic_ops);
298 }
299
300 module_init(init_basic)
301 module_exit(exit_basic)
302 MODULE_LICENSE("GPL");
303