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 * Copyright (c) 1998 Rajesh Vaidheeswarran 8 * All rights reserved. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 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 23 * permission. 24 * 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 35 * SUCH DAMAGE. 36 * 37 * Copyright (c) 1993 Terrence R. Lambert. 38 * All rights reserved. 39 * 40 * Redistribution and use in source and binary forms, with or without 41 * modification, are permitted provided that the following conditions 42 * are met: 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 53 * permission. 54 * 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 65 * SUCH DAMAGE. 66 * 67 * 68 * $FreeBSD$ 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 107 cdev_load(module_t mod, int cmd, void *arg) 108 { 109 int err = 0; 110 111 switch (cmd) { 112 case MOD_LOAD: 113 114 /* Do any initialization that you should do with the kernel */ 115 116 /* 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"); 122 break; /* Success*/ 123 124 case MOD_UNLOAD: 125 printf("Unloaded kld character device driver\n"); 126 destroy_dev(sdev); 127 break; /* Success*/ 128 129 default: /* we only understand load/unload*/ 130 err = EOPNOTSUPP; 131 break; 132 } 133 134 return(err); 135 } 136 137 /* Now declare the module to the system */ 138 139 DEV_MODULE(cdev, cdev_load, NULL); 140