aboutsummaryrefslogtreecommitdiffstats
path: root/net/sched/act_simple.c
blob: 97e84f3ee77563fb14aa7b8e0faf2db476a81501 (plain) (blame)
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
/*
 * net/sched/simp.c	Simple example of an action
 *
 *		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.
 *
 * Authors:	Jamal Hadi Salim (2005-8)
 *
 */

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/skbuff.h>
#include <linux/rtnetlink.h>
#include <net/netlink.h>
#include <net/pkt_sched.h>

#define TCA_ACT_SIMP 22

#include <linux/tc_act/tc_defact.h>
#include <net/tc_act/tc_defact.h>

#define SIMP_TAB_MASK     7
static struct tcf_common *tcf_simp_ht[SIMP_TAB_MASK + 1];
static u32 simp_idx_gen;
static DEFINE_RWLOCK(simp_lock);

static struct tcf_hashinfo simp_hash_info = {
	.htab	=	tcf_simp_ht,
	.hmask	=	SIMP_TAB_MASK,
	.lock	=	&simp_lock,
};

#define SIMP_MAX_DATA	32
static int tcf_simp(struct sk_buff *skb, struct tc_action *a, struct tcf_result *res)
{
	struct tcf_defact *d = a->priv;

	spin_lock(&d->tcf_lock);
	d->tcf_tm.lastuse = jiffies;
	d->tcf_bstats.bytes += qdisc_pkt_len(skb);
	d->tcf_bstats.packets++;

	/* print policy string followed by _ then packet count
	 * Example if this was the 3rd packet and the string was "hello"
	 * then it would look like "hello_3" (without quotes)
	 **/
	pr_info("simple: %s_%d\n",
	       (char *)d->tcfd_defdata, d->tcf_bstats.packets);
	spin_unlock(&d->tcf_lock);
	return d->tcf_action;
}

static int tcf_simp_release(struct tcf_defact *d, int bind)
{
	int ret = 0;
	if (d) {
		if (bind)
			d->tcf_bindcnt--;
		d->tcf_refcnt--;
		if (d->tcf_bindcnt <= 0 && d->tcf_refcnt <= 0) {
			kfree(d->tcfd_defdata);
			tcf_hash_destroy(&d->common, &simp_hash_info);
			ret = 1;
		}
	}
	return ret;
}

static int alloc_defdata(struct tcf_defact *d, char *defdata)
{
	d->tcfd_defdata = kzalloc(SIMP_MAX_DATA, GFP_KERNEL);
	if (unlikely(!d->tcfd_defdata))
		return -ENOMEM;
	strlcpy(d->tcfd_defdata, defdata, SIMP_MAX_DATA);
	return 0;
}

static void reset_policy(struct tcf_defact *d, char *defdata,
			 struct tc_defact *p)
{
	spin_lock_bh(&d->tcf_lock);
	d->tcf_action = p->action;
	memset(d->tcfd_defdata, 0, SIMP_MAX_DATA);
	strlcpy(d->tcfd_defdata, defdata, SIMP_MAX_DATA);
	spin_unlock_bh(&d->tcf_lock);
}

static const struct nla_policy simple_policy[TCA_DEF_MAX + 1] = {
	[TCA_DEF_PARMS]	= { .len = sizeof(struct tc_defact) },
	[TCA_DEF_DATA]	= { .type = NLA_STRING, .len = SIMP_MAX_DATA },
};

static int tcf_simp_init(struct nlattr *nla, struct nlattr *est,
			 struct tc_action *a, int ovr, int bind)
{
	struct nlattr *tb[TCA_DEF_MAX + 1];
	struct tc_defact *parm;
	struct tcf_defact *d;
	struct tcf_common *pc;
	char *defdata;
	int ret = 0, err;

	if (nla == NULL)
		return -EINVAL;

	err = nla_parse_nested(tb, TCA_DEF_MAX, nla, simple_policy);
	if (err < 0)
		return err;

	if (tb[TCA_DEF_PARMS] == NULL)
		return -EINVAL;

	if (tb[TCA_DEF_DATA] == NULL)
		return -EINVAL;

	parm = nla_data(tb[TCA_DEF_PARMS]);
	defdata = nla_data(tb[TCA_DEF_DATA]);

	pc = tcf_hash_check(parm->index, a, bind, &simp_hash_info);
	if (!pc) {
		pc = tcf_hash_create(parm->index, est, a, sizeof(*d), bind,
				     &simp_idx_gen, &simp_hash_info);
		if (IS_ERR(pc))
		    return PTR_ERR(pc);

		d = to_defact(pc);
		ret = alloc_defdata(d, defdata);
		if (ret < 0) {
			kfree(pc);
			return ret;
		}
		d->tcf_action = parm->action;
		ret = ACT_P_CREATED;
	} else {
		d = to_defact(pc);
		if (!ovr) {
			tcf_simp_release(d, bind);
			return -EEXIST;
		}
		reset_policy(d, defdata, parm);
	}

	if (ret == ACT_P_CREATED)
		tcf_hash_insert(pc, &simp_hash_info);
	return ret;
}

static inline int tcf_simp_cleanup(struct tc_action *a, int bind)
{
	struct tcf_defact *d = a->priv;

	if (d)
		return tcf_simp_release(d, bind);
	return 0;
}

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

	NLA_PUT(skb, TCA_DEF_PARMS, sizeof(opt), &opt);
	NLA_PUT_STRING(skb, TCA_DEF_DATA, d->tcfd_defdata);
	t.install = jiffies_to_clock_t(jiffies - d->tcf_tm.install);
	t.lastuse = jiffies_to_clock_t(jiffies - d->tcf_tm.lastuse);
	t.expires = jiffies_to_clock_t(d->tcf_tm.expires);
	NLA_PUT(skb, TCA_DEF_TM, sizeof(t), &t);
	return skb->len;

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

static struct tc_action_ops act_simp_ops = {
	.kind		=	"simple",
	.hinfo		=	&simp_hash_info,
	.type		=	TCA_ACT_SIMP,
	.capab		=	TCA_CAP_NONE,
	.owner		=	THIS_MODULE,
	.act		=	tcf_simp,
	.dump		=	tcf_simp_dump,
	.cleanup	=	tcf_simp_cleanup,
	.init		=	tcf_simp_init,
	.walk		=	tcf_generic_walker,
};

MODULE_AUTHOR("Jamal Hadi Salim(2005)");
MODULE_DESCRIPTION("Simple example action");
MODULE_LICENSE("GPL");

static int __init simp_init_module(void)
{
	int ret = tcf_register_action(&act_simp_ops);
	if (!ret)
		pr_info("Simple TC action Loaded\n");
	return ret;
}

static void __exit simp_cleanup_module(void)
{
	tcf_unregister_action(&act_simp_ops);
}

module_init(simp_init_module);
module_exit(simp_cleanup_module);