3 * cdevmod.c - a sample kld module implementing a character device driver.
5 * 08 Nov 1998 Rajesh Vaidheeswarran
7 * Copyright (c) 1998 Rajesh Vaidheeswarran
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by Rajesh Vaidheeswarran.
21 * 4. The name Rajesh Vaidheeswarran may not be used to endorse or promote
22 * products derived from this software without specific prior written
25 * THIS SOFTWARE IS PROVIDED BY RAJESH VAIDHEESWARRAN ``AS IS'' AND ANY
26 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED. IN NO EVENT SHALL THE RAJESH VAIDHEESWARRAN BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 * Copyright (c) 1993 Terrence R. Lambert.
38 * All rights reserved.
40 * Redistribution and use in source and binary forms, with or without
41 * modification, are permitted provided that the following conditions
43 * 1. Redistributions of source code must retain the above copyright
44 * notice, this list of conditions and the following disclaimer.
45 * 2. Redistributions in binary form must reproduce the above copyright
46 * notice, this list of conditions and the following disclaimer in the
47 * documentation and/or other materials provided with the distribution.
48 * 3. All advertising materials mentioning features or use of this software
49 * must display the following acknowledgement:
50 * This product includes software developed by Terrence R. Lambert.
51 * 4. The name Terrence R. Lambert may not be used to endorse or promote
52 * products derived from this software without specific prior written
55 * THIS SOFTWARE IS PROVIDED BY TERRENCE R. LAMBERT ``AS IS'' AND ANY
56 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
57 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
58 * ARE DISCLAIMED. IN NO EVENT SHALL THE TERRENCE R. LAMBERT BE LIABLE
59 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
60 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
61 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
62 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
63 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
64 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
70 #include <sys/param.h>
71 #include <sys/systm.h>
72 #include <sys/kernel.h>
73 #include <sys/module.h>
78 static struct cdevsw my_devsw = {
79 /* version */ .d_version = D_VERSION,
80 /* open */ .d_open = mydev_open,
81 /* close */ .d_close = mydev_close,
82 /* read */ .d_read = mydev_read,
83 /* write */ .d_write = mydev_write,
84 /* ioctl */ .d_ioctl = mydev_ioctl,
85 /* name */ .d_name = "cdev"
89 * Used as the variable that is the reference to our device
90 * in devfs... we must keep this variable sane until we
93 static struct cdev *sdev;
96 * This function is called each time the module is loaded or unloaded.
97 * Since we are a miscellaneous module, we have to provide whatever
98 * code is necessary to patch ourselves into the area we are being
101 * The stat information is basically common to all modules, so there
102 * is no real issue involved with stat; we will leave it lkm_nullcmd(),
103 * since we don't have to do anything about it.
107 cdev_load(module_t mod, int cmd, void *arg)
114 /* Do any initialization that you should do with the kernel */
116 /* if we make it to here, print copyright on console*/
117 printf("\nSample Loaded kld character device driver\n");
118 printf("Copyright (c) 1998\n");
119 printf("Rajesh Vaidheeswarran\n");
120 printf("All rights reserved\n");
121 sdev = make_dev(&my_devsw, 0, UID_ROOT, GID_WHEEL, 0600, "cdev");
125 printf("Unloaded kld character device driver\n");
129 default: /* we only understand load/unload*/
137 /* Now declare the module to the system */
139 DEV_MODULE(cdev, cdev_load, NULL);