1 /* 08 Nov 1998*/
2 /*-
3 * cdevmod.c - a sample kld module implementing a character device driver.
4 *
5 * 08 Nov 1998 Rajesh Vaidheeswarran
6 *
7 * SPDX-License-Identifier: BSD-4-Clause
8 *
9 * Copyright (c) 1998 Rajesh Vaidheeswarran
10 * All rights reserved.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. All advertising materials mentioning features or use of this software
21 * must display the following acknowledgement:
22 * This product includes software developed by Rajesh Vaidheeswarran.
23 * 4. The name Rajesh Vaidheeswarran may not be used to endorse or promote
24 * products derived from this software without specific prior written
25 * permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY RAJESH VAIDHEESWARRAN ``AS IS'' AND ANY
28 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 * ARE DISCLAIMED. IN NO EVENT SHALL THE RAJESH VAIDHEESWARRAN BE LIABLE
31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 * SUCH DAMAGE.
38 *
39 * Copyright (c) 1993 Terrence R. Lambert.
40 * All rights reserved.
41 *
42 * Redistribution and use in source and binary forms, with or without
43 * modification, are permitted provided that the following conditions
44 * are met:
45 * 1. Redistributions of source code must retain the above copyright
46 * notice, this list of conditions and the following disclaimer.
47 * 2. Redistributions in binary form must reproduce the above copyright
48 * notice, this list of conditions and the following disclaimer in the
49 * documentation and/or other materials provided with the distribution.
50 * 3. All advertising materials mentioning features or use of this software
51 * must display the following acknowledgement:
52 * This product includes software developed by Terrence R. Lambert.
53 * 4. The name Terrence R. Lambert may not be used to endorse or promote
54 * products derived from this software without specific prior written
55 * permission.
56 *
57 * THIS SOFTWARE IS PROVIDED BY TERRENCE R. LAMBERT ``AS IS'' AND ANY
58 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
59 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
60 * ARE DISCLAIMED. IN NO EVENT SHALL THE TERRENCE R. LAMBERT BE LIABLE
61 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
62 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
63 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
64 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
65 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
66 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
67 * SUCH DAMAGE.
68 *
69 */
70 #include <sys/param.h>
71 #include <sys/systm.h>
72 #include <sys/kernel.h>
73 #include <sys/module.h>
74 #include <sys/conf.h>
75
76 #include "cdev.h"
77
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"
86 };
87
88 /*
89 * Used as the variable that is the reference to our device
90 * in devfs... we must keep this variable sane until we
91 * call kldunload.
92 */
93 static struct cdev *sdev;
94
95 /*
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
99 * loaded to change.
100 *
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.
104 */
105
106 static int
cdev_load(module_t mod,int cmd,void * arg)107 cdev_load(module_t mod, int cmd, void *arg)
108 {
109 int err = 0;
110 struct make_dev_args mda;
111
112 switch (cmd) {
113 case MOD_LOAD:
114
115 /* Do any initialization that you should do with the kernel */
116
117 /* if we make it to here, print copyright on console*/
118 printf("\nSample Loaded kld character device driver\n");
119 printf("Copyright (c) 1998\n");
120 printf("Rajesh Vaidheeswarran\n");
121 printf("All rights reserved\n");
122
123 make_dev_args_init(&mda);
124 mda.mda_devsw = &my_devsw;
125 mda.mda_uid = UID_ROOT;
126 mda.mda_gid = GID_WHEEL;
127 mda.mda_mode = 0600;
128 err = make_dev_s(&mda, &sdev, "cdev");
129 break;
130
131 case MOD_UNLOAD:
132 printf("Unloaded kld character device driver\n");
133 destroy_dev(sdev);
134 break; /* Success*/
135
136 default: /* we only understand load/unload*/
137 err = EOPNOTSUPP;
138 break;
139 }
140
141 return(err);
142 }
143
144 /* Now declare the module to the system */
145
146 DEV_MODULE(cdev, cdev_load, NULL);
147