Merge branch 'linux-next' of git://git.infradead.org/ubifs-2.6
[pandora-kernel.git] / 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 const struct nla_policy gact_policy[TCA_GACT_MAX + 1] = {
57         [TCA_GACT_PARMS]        = { .len = sizeof(struct tc_gact) },
58         [TCA_GACT_PROB]         = { .len = sizeof(struct tc_gact_p) },
59 };
60
61 static int tcf_gact_init(struct nlattr *nla, struct nlattr *est,
62                          struct tc_action *a, int ovr, int bind)
63 {
64         struct nlattr *tb[TCA_GACT_MAX + 1];
65         struct tc_gact *parm;
66         struct tcf_gact *gact;
67         struct tcf_common *pc;
68         int ret = 0;
69         int err;
70
71         if (nla == NULL)
72                 return -EINVAL;
73
74         err = nla_parse_nested(tb, TCA_GACT_MAX, nla, gact_policy);
75         if (err < 0)
76                 return err;
77
78         if (tb[TCA_GACT_PARMS] == NULL)
79                 return -EINVAL;
80         parm = nla_data(tb[TCA_GACT_PARMS]);
81
82 #ifndef CONFIG_GACT_PROB
83         if (tb[TCA_GACT_PROB] != NULL)
84                 return -EOPNOTSUPP;
85 #endif
86
87         pc = tcf_hash_check(parm->index, a, bind, &gact_hash_info);
88         if (!pc) {
89                 pc = tcf_hash_create(parm->index, est, a, sizeof(*gact),
90                                      bind, &gact_idx_gen, &gact_hash_info);
91                 if (IS_ERR(pc))
92                         return PTR_ERR(pc);
93                 ret = ACT_P_CREATED;
94         } else {
95                 if (!ovr) {
96                         tcf_hash_release(pc, bind, &gact_hash_info);
97                         return -EEXIST;
98                 }
99         }
100
101         gact = to_gact(pc);
102
103         spin_lock_bh(&gact->tcf_lock);
104         gact->tcf_action = parm->action;
105 #ifdef CONFIG_GACT_PROB
106         if (tb[TCA_GACT_PROB] != NULL) {
107                 struct tc_gact_p *p_parm = nla_data(tb[TCA_GACT_PROB]);
108                 gact->tcfg_paction = p_parm->paction;
109                 gact->tcfg_pval    = p_parm->pval;
110                 gact->tcfg_ptype   = p_parm->ptype;
111         }
112 #endif
113         spin_unlock_bh(&gact->tcf_lock);
114         if (ret == ACT_P_CREATED)
115                 tcf_hash_insert(pc, &gact_hash_info);
116         return ret;
117 }
118
119 static int tcf_gact_cleanup(struct tc_action *a, int bind)
120 {
121         struct tcf_gact *gact = a->priv;
122
123         if (gact)
124                 return tcf_hash_release(&gact->common, bind, &gact_hash_info);
125         return 0;
126 }
127
128 static int tcf_gact(struct sk_buff *skb, struct tc_action *a, struct tcf_result *res)
129 {
130         struct tcf_gact *gact = a->priv;
131         int action = TC_ACT_SHOT;
132
133         spin_lock(&gact->tcf_lock);
134 #ifdef CONFIG_GACT_PROB
135         if (gact->tcfg_ptype && gact_rand[gact->tcfg_ptype] != NULL)
136                 action = gact_rand[gact->tcfg_ptype](gact);
137         else
138                 action = gact->tcf_action;
139 #else
140         action = gact->tcf_action;
141 #endif
142         gact->tcf_bstats.bytes += qdisc_pkt_len(skb);
143         gact->tcf_bstats.packets++;
144         if (action == TC_ACT_SHOT)
145                 gact->tcf_qstats.drops++;
146         gact->tcf_tm.lastuse = jiffies;
147         spin_unlock(&gact->tcf_lock);
148
149         return action;
150 }
151
152 static int tcf_gact_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
153 {
154         unsigned char *b = skb_tail_pointer(skb);
155         struct tcf_gact *gact = a->priv;
156         struct tc_gact opt = {
157                 .index   = gact->tcf_index,
158                 .refcnt  = gact->tcf_refcnt - ref,
159                 .bindcnt = gact->tcf_bindcnt - bind,
160                 .action  = gact->tcf_action,
161         };
162         struct tcf_t t;
163
164         NLA_PUT(skb, TCA_GACT_PARMS, sizeof(opt), &opt);
165 #ifdef CONFIG_GACT_PROB
166         if (gact->tcfg_ptype) {
167                 struct tc_gact_p p_opt = {
168                         .paction = gact->tcfg_paction,
169                         .pval    = gact->tcfg_pval,
170                         .ptype   = gact->tcfg_ptype,
171                 };
172
173                 NLA_PUT(skb, TCA_GACT_PROB, sizeof(p_opt), &p_opt);
174         }
175 #endif
176         t.install = jiffies_to_clock_t(jiffies - gact->tcf_tm.install);
177         t.lastuse = jiffies_to_clock_t(jiffies - gact->tcf_tm.lastuse);
178         t.expires = jiffies_to_clock_t(gact->tcf_tm.expires);
179         NLA_PUT(skb, TCA_GACT_TM, sizeof(t), &t);
180         return skb->len;
181
182 nla_put_failure:
183         nlmsg_trim(skb, b);
184         return -1;
185 }
186
187 static struct tc_action_ops act_gact_ops = {
188         .kind           =       "gact",
189         .hinfo          =       &gact_hash_info,
190         .type           =       TCA_ACT_GACT,
191         .capab          =       TCA_CAP_NONE,
192         .owner          =       THIS_MODULE,
193         .act            =       tcf_gact,
194         .dump           =       tcf_gact_dump,
195         .cleanup        =       tcf_gact_cleanup,
196         .lookup         =       tcf_hash_search,
197         .init           =       tcf_gact_init,
198         .walk           =       tcf_generic_walker
199 };
200
201 MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
202 MODULE_DESCRIPTION("Generic Classifier actions");
203 MODULE_LICENSE("GPL");
204
205 static int __init gact_init_module(void)
206 {
207 #ifdef CONFIG_GACT_PROB
208         pr_info("GACT probability on\n");
209 #else
210         pr_info("GACT probability NOT on\n");
211 #endif
212         return tcf_register_action(&act_gact_ops);
213 }
214
215 static void __exit gact_cleanup_module(void)
216 {
217         tcf_unregister_action(&act_gact_ops);
218 }
219
220 module_init(gact_init_module);
221 module_exit(gact_cleanup_module);