1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 1999 Assar Westerlund 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 * 28 * $FreeBSD$ 29 */ 30 31 #include <sys/param.h> 32 #include <sys/proc.h> 33 #include <sys/module.h> 34 #include <sys/sysproto.h> 35 #include <sys/sysent.h> 36 #include <sys/kernel.h> 37 #include <sys/systm.h> 38 39 /* 40 * The function for implementing the syscall. 41 */ 42 static int 43 hello(struct thread *td, void *arg) 44 { 45 46 printf("hello kernel\n"); 47 return (0); 48 } 49 50 /* 51 * The `sysent' for the new syscall 52 */ 53 static struct sysent hello_sysent = { 54 0, /* sy_narg */ 55 hello /* sy_call */ 56 }; 57 58 /* 59 * The offset in sysent where the syscall is allocated. 60 */ 61 static int offset = NO_SYSCALL; 62 63 /* 64 * The function called at load/unload. 65 */ 66 static int 67 load(struct module *module, int cmd, void *arg) 68 { 69 int error = 0; 70 71 switch (cmd) { 72 case MOD_LOAD : 73 printf("syscall loaded at %d\n", offset); 74 break; 75 case MOD_UNLOAD : 76 printf("syscall unloaded from %d\n", offset); 77 break; 78 default : 79 error = EOPNOTSUPP; 80 break; 81 } 82 return (error); 83 } 84 85 SYSCALL_MODULE(syscall, &offset, &hello_sysent, load, NULL); 86