Merge branch 'upstream-jeff' of git://git.kernel.org/pub/scm/linux/kernel/git/romieu...
[linux-2.6] / net / sched / act_gact.c
1 /*
2  * net/sched/gact.c     Generic actions
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  * copyright    Jamal Hadi Salim (2002-4)
10  *
11  */
12
13 #include <linux/types.h>
14 #include <linux/kernel.h>
15 #include <linux/string.h>
16 #include <linux/errno.h>
17 #include <linux/skbuff.h>
18 #include <linux/rtnetlink.h>
19 #include <linux/module.h>
20 #include <linux/init.h>
21 #include <net/netlink.h>
22 #include <net/pkt_sched.h>
23 #include <linux/tc_act/tc_gact.h>
24 #include <net/tc_act/tc_gact.h>
25
26 #define GACT_TAB_MASK   15
27 static struct tcf_common *tcf_gact_ht[GACT_TAB_MASK + 1];
28 static u32 gact_idx_gen;
29 static DEFINE_RWLOCK(gact_lock);
30
31 static struct tcf_hashinfo gact_hash_info = {
32         .htab   =       tcf_gact_ht,
33         .hmask  =       GACT_TAB_MASK,
34         .lock   =       &gact_lock,
35 };
36
37 #ifdef CONFIG_GACT_PROB
38 static int gact_net_rand(struct tcf_gact *gact)
39 {
40         if (!gact->tcfg_pval || net_random() % gact->tcfg_pval)
41                 return gact->tcf_action;
42         return gact->tcfg_paction;
43 }
44
45 static int gact_determ(struct tcf_gact *gact)
46 {
47         if (!gact->tcfg_pval || gact->tcf_bstats.packets % gact->tcfg_pval)
48                 return gact->tcf_action;
49         return gact->tcfg_paction;
50 }
51
52 typedef int (*g_rand)(struct tcf_gact *gact);
53 static g_rand gact_rand[MAX_RAND]= { NULL, gact_net_rand, gact_determ };
54 #endif /* CONFIG_GACT_PROB */
55
56 static int tcf_gact_init(struct rtattr *rta, struct rtattr *est,
57                          struct tc_action *a, int ovr, int bind)
58 {
59         struct rtattr *tb[TCA_GACT_MAX];
60         struct tc_gact *parm;
61         struct tcf_gact *gact;
62         struct tcf_common *pc;
63         int ret = 0;
64
65         if (rta == NULL || rtattr_parse_nested(tb, TCA_GACT_MAX, rta) < 0)
66                 return -EINVAL;
67
68         if (tb[TCA_GACT_PARMS - 1] == NULL ||
69             RTA_PAYLOAD(tb[TCA_GACT_PARMS - 1]) < sizeof(*parm))
70                 return -EINVAL;
71         parm = RTA_DATA(tb[TCA_GACT_PARMS - 1]);
72
73         if (tb[TCA_GACT_PROB-1] != NULL)
74 #ifdef CONFIG_GACT_PROB
75                 if (RTA_PAYLOAD(tb[TCA_GACT_PROB-1]) < sizeof(struct tc_gact_p))
76                         return -EINVAL;
77 #else
78                 return -EOPNOTSUPP;
79 #endif
80
81         pc = tcf_hash_check(parm->index, a, bind, &gact_hash_info);
82         if (!pc) {
83                 pc = tcf_hash_create(parm->index, est, a, sizeof(*gact),
84                                      bind, &gact_idx_gen, &gact_hash_info);
85                 if (unlikely(!pc))
86                         return -ENOMEM;
87                 ret = ACT_P_CREATED;
88         } else {
89                 if (!ovr) {
90                         tcf_hash_release(pc, bind, &gact_hash_info);
91                         return -EEXIST;
92                 }
93         }
94
95         gact = to_gact(pc);
96
97         spin_lock_bh(&gact->tcf_lock);
98         gact->tcf_action = parm->action;
99 #ifdef CONFIG_GACT_PROB
100         if (tb[TCA_GACT_PROB-1] != NULL) {
101                 struct tc_gact_p *p_parm = RTA_DATA(tb[TCA_GACT_PROB-1]);
102                 gact->tcfg_paction = p_parm->paction;
103                 gact->tcfg_pval    = p_parm->pval;
104                 gact->tcfg_ptype   = p_parm->ptype;
105         }
106 #endif
107         spin_unlock_bh(&gact->tcf_lock);
108         if (ret == ACT_P_CREATED)
109                 tcf_hash_insert(pc, &gact_hash_info);
110         return ret;
111 }
112
113 static int tcf_gact_cleanup(struct tc_action *a, int bind)
114 {
115         struct tcf_gact *gact = a->priv;
116
117         if (gact)
118                 return tcf_hash_release(&gact->common, bind, &gact_hash_info);
119         return 0;
120 }
121
122 static int tcf_gact(struct sk_buff *skb, struct tc_action *a, struct tcf_result *res)
123 {
124         struct tcf_gact *gact = a->priv;
125         int action = TC_ACT_SHOT;
126
127         spin_lock(&gact->tcf_lock);
128 #ifdef CONFIG_GACT_PROB
129         if (gact->tcfg_ptype && gact_rand[gact->tcfg_ptype] != NULL)
130                 action = gact_rand[gact->tcfg_ptype](gact);
131         else
132                 action = gact->tcf_action;
133 #else
134         action = gact->tcf_action;
135 #endif
136         gact->tcf_bstats.bytes += skb->len;
137         gact->tcf_bstats.packets++;
138         if (action == TC_ACT_SHOT)
139                 gact->tcf_qstats.drops++;
140         gact->tcf_tm.lastuse = jiffies;
141         spin_unlock(&gact->tcf_lock);
142
143         return action;
144 }
145
146 static int tcf_gact_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
147 {
148         unsigned char *b = skb_tail_pointer(skb);
149         struct tc_gact opt;
150         struct tcf_gact *gact = a->priv;
151         struct tcf_t t;
152
153         opt.index = gact->tcf_index;
154         opt.refcnt = gact->tcf_refcnt - ref;
155         opt.bindcnt = gact->tcf_bindcnt - bind;
156         opt.action = gact->tcf_action;
157         RTA_PUT(skb, TCA_GACT_PARMS, sizeof(opt), &opt);
158 #ifdef CONFIG_GACT_PROB
159         if (gact->tcfg_ptype) {
160                 struct tc_gact_p p_opt;
161                 p_opt.paction = gact->tcfg_paction;
162                 p_opt.pval = gact->tcfg_pval;
163                 p_opt.ptype = gact->tcfg_ptype;
164                 RTA_PUT(skb, TCA_GACT_PROB, sizeof(p_opt), &p_opt);
165         }
166 #endif
167         t.install = jiffies_to_clock_t(jiffies - gact->tcf_tm.install);
168         t.lastuse = jiffies_to_clock_t(jiffies - gact->tcf_tm.lastuse);
169         t.expires = jiffies_to_clock_t(gact->tcf_tm.expires);
170         RTA_PUT(skb, TCA_GACT_TM, sizeof(t), &t);
171         return skb->len;
172
173 rtattr_failure:
174         nlmsg_trim(skb, b);
175         return -1;
176 }
177
178 static struct tc_action_ops act_gact_ops = {
179         .kind           =       "gact",
180         .hinfo          =       &gact_hash_info,
181         .type           =       TCA_ACT_GACT,
182         .capab          =       TCA_CAP_NONE,
183         .owner          =       THIS_MODULE,
184         .act            =       tcf_gact,
185         .dump           =       tcf_gact_dump,
186         .cleanup        =       tcf_gact_cleanup,
187         .lookup         =       tcf_hash_search,
188         .init           =       tcf_gact_init,
189         .walk           =       tcf_generic_walker
190 };
191
192 MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
193 MODULE_DESCRIPTION("Generic Classifier actions");
194 MODULE_LICENSE("GPL");
195
196 static int __init gact_init_module(void)
197 {
198 #ifdef CONFIG_GACT_PROB
199         printk("GACT probability on\n");
200 #else
201         printk("GACT probability NOT on\n");
202 #endif
203         return tcf_register_action(&act_gact_ops);
204 }
205
206 static void __exit gact_cleanup_module(void)
207 {
208         tcf_unregister_action(&act_gact_ops);
209 }
210
211 module_init(gact_init_module);
212 module_exit(gact_cleanup_module);