xref: /linux/samples/connector/cn_test.c (revision be709d48329a500621d2a05835283150ae137b45)
1 /*
2  * 	cn_test.c
3  *
4  * 2004+ Copyright (c) Evgeniy Polyakov <zbr@ioremap.net>
5  * All rights reserved.
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
20  */
21 
22 #define pr_fmt(fmt) "cn_test: " fmt
23 
24 #include <linux/kernel.h>
25 #include <linux/module.h>
26 #include <linux/moduleparam.h>
27 #include <linux/skbuff.h>
28 #include <linux/slab.h>
29 #include <linux/timer.h>
30 
31 #include <linux/connector.h>
32 
33 static struct cb_id cn_test_id = { CN_NETLINK_USERS + 3, 0x456 };
34 static char cn_test_name[] = "cn_test";
35 static struct sock *nls;
36 static struct timer_list cn_test_timer;
37 
38 static void cn_test_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp)
39 {
40 	pr_info("%s: %lu: idx=%x, val=%x, seq=%u, ack=%u, len=%d: %s.\n",
41 	        __func__, jiffies, msg->id.idx, msg->id.val,
42 	        msg->seq, msg->ack, msg->len,
43 	        msg->len ? (char *)msg->data : "");
44 }
45 
46 /*
47  * Do not remove this function even if no one is using it as
48  * this is an example of how to get notifications about new
49  * connector user registration
50  */
51 #if 0
52 static int cn_test_want_notify(void)
53 {
54 	struct cn_ctl_msg *ctl;
55 	struct cn_notify_req *req;
56 	struct cn_msg *msg = NULL;
57 	int size, size0;
58 	struct sk_buff *skb;
59 	struct nlmsghdr *nlh;
60 	u32 group = 1;
61 
62 	size0 = sizeof(*msg) + sizeof(*ctl) + 3 * sizeof(*req);
63 
64 	size = NLMSG_SPACE(size0);
65 
66 	skb = alloc_skb(size, GFP_ATOMIC);
67 	if (!skb) {
68 		pr_err("failed to allocate new skb with size=%u\n", size);
69 		return -ENOMEM;
70 	}
71 
72 	nlh = nlmsg_put(skb, 0, 0x123, NLMSG_DONE, size - sizeof(*nlh), 0);
73 	if (!nlh) {
74 		kfree_skb(skb);
75 		return -EMSGSIZE;
76 	}
77 
78 	msg = nlmsg_data(nlh);
79 
80 	memset(msg, 0, size0);
81 
82 	msg->id.idx = -1;
83 	msg->id.val = -1;
84 	msg->seq = 0x123;
85 	msg->ack = 0x345;
86 	msg->len = size0 - sizeof(*msg);
87 
88 	ctl = (struct cn_ctl_msg *)(msg + 1);
89 
90 	ctl->idx_notify_num = 1;
91 	ctl->val_notify_num = 2;
92 	ctl->group = group;
93 	ctl->len = msg->len - sizeof(*ctl);
94 
95 	req = (struct cn_notify_req *)(ctl + 1);
96 
97 	/*
98 	 * Idx.
99 	 */
100 	req->first = cn_test_id.idx;
101 	req->range = 10;
102 
103 	/*
104 	 * Val 0.
105 	 */
106 	req++;
107 	req->first = cn_test_id.val;
108 	req->range = 10;
109 
110 	/*
111 	 * Val 1.
112 	 */
113 	req++;
114 	req->first = cn_test_id.val + 20;
115 	req->range = 10;
116 
117 	NETLINK_CB(skb).dst_group = ctl->group;
118 	//netlink_broadcast(nls, skb, 0, ctl->group, GFP_ATOMIC);
119 	netlink_unicast(nls, skb, 0, 0);
120 
121 	pr_info("request was sent: group=0x%x\n", ctl->group);
122 
123 	return 0;
124 }
125 #endif
126 
127 static u32 cn_test_timer_counter;
128 static void cn_test_timer_func(struct timer_list *unused)
129 {
130 	struct cn_msg *m;
131 	char data[32];
132 
133 	pr_debug("%s: timer fired\n", __func__);
134 
135 	m = kzalloc(sizeof(*m) + sizeof(data), GFP_ATOMIC);
136 	if (m) {
137 
138 		memcpy(&m->id, &cn_test_id, sizeof(m->id));
139 		m->seq = cn_test_timer_counter;
140 		m->len = sizeof(data);
141 
142 		m->len =
143 		    scnprintf(data, sizeof(data), "counter = %u",
144 			      cn_test_timer_counter) + 1;
145 
146 		memcpy(m + 1, data, m->len);
147 
148 		cn_netlink_send(m, 0, 0, GFP_ATOMIC);
149 		kfree(m);
150 	}
151 
152 	cn_test_timer_counter++;
153 
154 	mod_timer(&cn_test_timer, jiffies + msecs_to_jiffies(1000));
155 }
156 
157 static int cn_test_init(void)
158 {
159 	int err;
160 
161 	err = cn_add_callback(&cn_test_id, cn_test_name, cn_test_callback);
162 	if (err)
163 		goto err_out;
164 	cn_test_id.val++;
165 	err = cn_add_callback(&cn_test_id, cn_test_name, cn_test_callback);
166 	if (err) {
167 		cn_del_callback(&cn_test_id);
168 		goto err_out;
169 	}
170 
171 	timer_setup(&cn_test_timer, cn_test_timer_func, 0);
172 	mod_timer(&cn_test_timer, jiffies + msecs_to_jiffies(1000));
173 
174 	pr_info("initialized with id={%u.%u}\n",
175 		cn_test_id.idx, cn_test_id.val);
176 
177 	return 0;
178 
179       err_out:
180 	if (nls && nls->sk_socket)
181 		sock_release(nls->sk_socket);
182 
183 	return err;
184 }
185 
186 static void cn_test_fini(void)
187 {
188 	del_timer_sync(&cn_test_timer);
189 	cn_del_callback(&cn_test_id);
190 	cn_test_id.val--;
191 	cn_del_callback(&cn_test_id);
192 	if (nls && nls->sk_socket)
193 		sock_release(nls->sk_socket);
194 }
195 
196 module_init(cn_test_init);
197 module_exit(cn_test_fini);
198 
199 MODULE_LICENSE("GPL");
200 MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>");
201 MODULE_DESCRIPTION("Connector's test module");
202