test.c

以前做的操作系统的课程设计,内容包括：1)编写一个C程序

#define _NO_VERSION_
#include <linux/module.h>
#include <linux/version.h>
 
#include <linux/config.h>
#include <asm/uaccess.h>
#include <linux/types.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/errno.h>
#include <asm/segment.h>
#include <linux/kernel.h>

extern int errno;
unsigned int test_major=0;
char kernel_version []=UTS_RELEASE;


static ssize_t read_test(struct file * file,char *buf,size_t count,loff_t * f_pos)　
　//读数
 {
    int left;
   /* if(verify_area(VERIFY_WRITE,buf,count) == -EFAULT )
           return -EFAULT;*/

    for(left=count;left>0;left--)
    {
        __put_user(1,buf);
        buf++;
    }
    return  count;  	
}


static ssize_t write_test(struct file * file,const char *buf,size_t count,loff_t *f_pos)　　
　　　                                         //写数
{
    return count;
}

static int open_test(struct inode * node,struct file * file)　//打开设备
{
    MOD_INC_USE_COUNT;
    return 0;
}

static int release_test(struct inode * inode,struct file * file)　　//关闭设备
{
    MOD_DEC_USE_COUNT;
        return 0;
}


struct file_operations test_fops ={
 read:read_test,
 write:write_test,
 open:open_test,
 release:release_test
  };

int init_module(void)　　//模块初始化
{
    int result;
    result = register_chrdev(0,"mydev",&test_fops);
    if(result < 0)	
    {
        printk("mydev: can't get major number.\n");
        return result;
    }

    if(test_major==0) test_major=result;
    return 0;
}
void cleanup_module(void)　　　//模块删除
{    
     unregister_chrdev(test_major,"mydev");
}