7320fd3a30
of supported operations by example read() and write() operations. Inspired by: http://www.daemonnews.org/200010/blueprints.html PR: 16173 Submitted by: sobomax
149 lines
5.3 KiB
C
149 lines
5.3 KiB
C
/* 08 Nov 1998*/
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/*
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* cdevmod.c - a sample kld module implementing a character device driver.
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*
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* 08 Nov 1998 Rajesh Vaidheeswarran
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*
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* Copyright (c) 1998 Rajesh Vaidheeswarran
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by Rajesh Vaidheeswarran.
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* 4. The name Rajesh Vaidheeswarran may not be used to endorse or promote
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* products derived from this software without specific prior written
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* permission.
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*
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* THIS SOFTWARE IS PROVIDED BY RAJESH VAIDHEESWARRAN ``AS IS'' AND ANY
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* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE RAJESH VAIDHEESWARRAN BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* Copyright (c) 1993 Terrence R. Lambert.
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by Terrence R. Lambert.
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* 4. The name Terrence R. Lambert may not be used to endorse or promote
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* products derived from this software without specific prior written
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* permission.
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*
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* THIS SOFTWARE IS PROVIDED BY TERRENCE R. LAMBERT ``AS IS'' AND ANY
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* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE TERRENCE R. LAMBERT BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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*
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* $FreeBSD$
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*/
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/kernel.h>
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#include <sys/module.h>
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#include <sys/conf.h>
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#include "cdev.h"
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#define CDEV_MAJOR 32
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static struct cdevsw my_devsw = {
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/* open */ mydev_open,
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/* close */ mydev_close,
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/* read */ mydev_read,
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/* write */ mydev_write,
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/* ioctl */ mydev_ioctl,
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/* poll */ nopoll,
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/* mmap */ nommap,
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/* strategy */ nostrategy,
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/* name */ "cdev",
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/* maj */ CDEV_MAJOR,
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/* dump */ nodump,
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/* psize */ nopsize,
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/* flags */ D_TTY,
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/* bmaj */ -1
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};
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/*
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* Used as the variable that is the reference to our device
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* in devfs... we must keep this variable sane until we
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* call kldunload.
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*/
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static dev_t sdev;
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/*
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* This function is called each time the module is loaded or unloaded.
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* Since we are a miscellaneous module, we have to provide whatever
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* code is necessary to patch ourselves into the area we are being
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* loaded to change.
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*
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* The stat information is basically common to all modules, so there
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* is no real issue involved with stat; we will leave it lkm_nullcmd(),
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* since we don't have to do anything about it.
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*/
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static int
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cdev_load(module_t mod, int cmd, void *arg)
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{
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int err = 0;
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switch (cmd) {
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case MOD_LOAD:
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/* Do any initialization that you should do with the kernel */
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/* if we make it to here, print copyright on console*/
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printf("\nSample Loaded kld character device driver\n");
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printf("Copyright (c) 1998\n");
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printf("Rajesh Vaidheeswarran\n");
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printf("All rights reserved\n");
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sdev = make_dev(&my_devsw, 0, UID_ROOT, GID_WHEEL, 0600, "cdev");
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break; /* Success*/
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case MOD_UNLOAD:
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printf("Unloaded kld character device driver\n");
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destroy_dev(sdev);
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break; /* Success*/
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default: /* we only understand load/unload*/
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err = EINVAL;
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break;
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}
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return(err);
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}
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/* Now declare the module to the system */
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DEV_MODULE(cdev, cdev_load, NULL);
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