aboutsummaryrefslogtreecommitdiffstats
path: root/net/sched/act_gact.c
blob: b77f5a06a658f56bf3733ab72918aa63aedd1c16 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
/*
 * net/sched/gact.c	Generic actions
 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 *
 * copyright 	Jamal Hadi Salim (2002-4)
 *
 */

#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/skbuff.h>
#include <linux/rtnetlink.h>
#include <linux/module.h>
#include <linux/init.h>
#include <net/netlink.h>
#include <net/pkt_sched.h>
#include <linux/tc_act/tc_gact.h>
#include <net/tc_act/tc_gact.h>

#define GACT_TAB_MASK	15
static struct tcf_common *tcf_gact_ht[GACT_TAB_MASK + 1];
static u32 gact_idx_gen;
static DEFINE_RWLOCK(gact_lock);

static struct tcf_hashinfo gact_hash_info = {
	.htab	=	tcf_gact_ht,
	.hmask	=	GACT_TAB_MASK,
	.lock	=	&gact_lock,
};

#ifdef CONFIG_GACT_PROB
static int gact_net_rand(struct tcf_gact *gact)
{
	if (!gact->tcfg_pval || net_random() % gact->tcfg_pval)
		return gact->tcf_action;
	return gact->tcfg_paction;
}

static int gact_determ(struct tcf_gact *gact)
{
	if (!gact->tcfg_pval || gact->tcf_bstats.packets % gact->tcfg_pval)
		return gact->tcf_action;
	return gact->tcfg_paction;
}

typedef int (*g_rand)(struct tcf_gact *gact);
static g_rand gact_rand[MAX_RAND] = { NULL, gact_net_rand, gact_determ };
#endif /* CONFIG_GACT_PROB */

static const struct nla_policy gact_policy[TCA_GACT_MAX + 1] = {
	[TCA_GACT_PARMS]	= { .len = sizeof(struct tc_gact) },
	[TCA_GACT_PROB]		= { .len = sizeof(struct tc_gact_p) },
};

static int tcf_gact_init(struct nlattr *nla, struct nlattr *est,
			 struct tc_action *a, int ovr, int bind)
{
	struct nlattr *tb[TCA_GACT_MAX + 1];
	struct tc_gact *parm;
	struct tcf_gact *gact;
	struct tcf_common *pc;
	int ret = 0;
	int err;

	if (nla == NULL)
		return -EINVAL;

	err = nla_parse_nested(tb, TCA_GACT_MAX, nla, gact_policy);
	if (err < 0)
		return err;

	if (tb[TCA_GACT_PARMS] == NULL)
		return -EINVAL;
	parm = nla_data(tb[TCA_GACT_PARMS]);

#ifndef CONFIG_GACT_PROB
	if (tb[TCA_GACT_PROB] != NULL)
		return -EOPNOTSUPP;
#endif

	pc = tcf_hash_check(parm->index, a, bind, &gact_hash_info);
	if (!pc) {
		pc = tcf_hash_create(parm->index, est, a, sizeof(*gact),
				     bind, &gact_idx_gen, &gact_hash_info);
		if (IS_ERR(pc))
			return PTR_ERR(pc);
		ret = ACT_P_CREATED;
	} else {
		if (!ovr) {
			tcf_hash_release(pc, bind, &gact_hash_info);
			return -EEXIST;
		}
	}

	gact = to_gact(pc);

	spin_lock_bh(&gact->tcf_lock);
	gact->tcf_action = parm->action;
#ifdef CONFIG_GACT_PROB
	if (tb[TCA_GACT_PROB] != NULL) {
		struct tc_gact_p *p_parm = nla_data(tb[TCA_GACT_PROB]);
		gact->tcfg_paction = p_parm->paction;
		gact->tcfg_pval    = p_parm->pval;
		gact->tcfg_ptype   = p_parm->ptype;
	}
#endif
	spin_unlock_bh(&gact->tcf_lock);
	if (ret == ACT_P_CREATED)
		tcf_hash_insert(pc, &gact_hash_info);
	return ret;
}

static int tcf_gact_cleanup(struct tc_action *a, int bind)
{
	struct tcf_gact *gact = a->priv;

	if (gact)
		return tcf_hash_release(&gact->common, bind, &gact_hash_info);
	return 0;
}

static int tcf_gact(struct sk_buff *skb, const struct tc_action *a,
		    struct tcf_result *res)
{
	struct tcf_gact *gact = a->priv;
	int action = TC_ACT_SHOT;

	spin_lock(&gact->tcf_lock);
#ifdef CONFIG_GACT_PROB
	if (gact->tcfg_ptype && gact_rand[gact->tcfg_ptype] != NULL)
		action = gact_rand[gact->tcfg_ptype](gact);
	else
		action = gact->tcf_action;
#else
	action = gact->tcf_action;
#endif
	gact->tcf_bstats.bytes += qdisc_pkt_len(skb);
	gact->tcf_bstats.packets++;
	if (action == TC_ACT_SHOT)
		gact->tcf_qstats.drops++;
	gact->tcf_tm.lastuse = jiffies;
	spin_unlock(&gact->tcf_lock);

	return action;
}

static int tcf_gact_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
{
	unsigned char *b = skb_tail_pointer(skb);
	struct tcf_gact *gact = a->priv;
	struct tc_gact opt = {
		.index   = gact->tcf_index,
		.refcnt  = gact->tcf_refcnt - ref,
		.bindcnt = gact->tcf_bindcnt - bind,
		.action  = gact->tcf_action,
	};
	struct tcf_t t;

	NLA_PUT(skb, TCA_GACT_PARMS, sizeof(opt), &opt);
#ifdef CONFIG_GACT_PROB
	if (gact->tcfg_ptype) {
		struct tc_gact_p p_opt = {
			.paction = gact->tcfg_paction,
			.pval    = gact->tcfg_pval,
			.ptype   = gact->tcfg_ptype,
		};

		NLA_PUT(skb, TCA_GACT_PROB, sizeof(p_opt), &p_opt);
	}
#endif
	t.install = jiffies_to_clock_t(jiffies - gact->tcf_tm.install);
	t.lastuse = jiffies_to_clock_t(jiffies - gact->tcf_tm.lastuse);
	t.expires = jiffies_to_clock_t(gact->tcf_tm.expires);
	NLA_PUT(skb, TCA_GACT_TM, sizeof(t), &t);
	return skb->len;

nla_put_failure:
	nlmsg_trim(skb, b);
	return -1;
}

static struct tc_action_ops act_gact_ops = {
	.kind		=	"gact",
	.hinfo		=	&gact_hash_info,
	.type		=	TCA_ACT_GACT,
	.capab		=	TCA_CAP_NONE,
	.owner		=	THIS_MODULE,
	.act		=	tcf_gact,
	.dump		=	tcf_gact_dump,
	.cleanup	=	tcf_gact_cleanup,
	.lookup		=	tcf_hash_search,
	.init		=	tcf_gact_init,
	.walk		=	tcf_generic_walker
};

MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
MODULE_DESCRIPTION("Generic Classifier actions");
MODULE_LICENSE("GPL");

static int __init gact_init_module(void)
{
#ifdef CONFIG_GACT_PROB
	pr_info("GACT probability on\n");
#else
	pr_info("GACT probability NOT on\n");
#endif
	return tcf_register_action(&act_gact_ops);
}

static void __exit gact_cleanup_module(void)
{
	tcf_unregister_action(&act_gact_ops);
}

module_init(gact_init_module);
module_exit(gact_cleanup_module);