调用linux 内核模块测试

[root@openstack01 TestModule2]# uname -a

Linux openstack01 3.10.0-514.el7.x86_64 #1 SMP Tue Nov 22 16:42:41 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux

Makefile:

obj-m:=TestModule.o
VERSION_NUM:=$(shell uname -r)  
KERNELBUILD := /lib/modules/`uname -r`/build  
CURRENT_PATH:=$(shell pwd)  
  
all:  
make -C $(KERNELBUILD) M=$(CURRENT_PATH) modules  
  
clean:  
make -C $(KERNELBUILD) M=$(CURRENT_PATH) clean 

[root@openstack01 TestModule2]# cat TestModule.c

#ifndef _KERNEL_  
        #define _KERNEL_  
#endif  
  
#ifndef MODULE  
        #define MODULE  
#endif  
  
  
#include <linux/module.h>  
#include <linux/kernel.h>  
#include <linux/version.h>  
#include <linux/types.h>  
#include <linux/fs.h>  
#include <linux/mm.h>  
#include <linux/utsrelease.h>  
#include <linux/errno.h>  
#include <asm/segment.h>  
#include <linux/sched.h>  
#include <asm/uaccess.h>  
  
#define DATA_LENGTH 10  
  
MODULE_LICENSE("GPL");  
MODULE_AUTHOR("TUO LI HENG");  
  
char kernel_version[] = UTS_RELEASE;  
  
unsigned int test_major = 0;  
  
ssize_t read_test(struct file *file, char * buf, size_t count, loff_t *f_ops)  
{  
        int left, i, *p;  
        int data[DATA_LENGTH];  
        p = data;  
        for(i=0; i<10; ++i)  
                data[i] = 61;  
  
        for(left=count; left>0; --left)  
        {  
                copy_to_user(buf, p, 1);  
                ++buf;  
                ++p;  
        }  
        return 0;  
  
}  
  
ssize_t write_test(struct file *file, char * buf, size_t count, loff_t *f_ops)  
{  
  
        return 0;  
}  
  
static int open_test(struct inode* inode, struct file *file)  
{  
        return 0;  
  
}  
  
static int release_test(struct inode *inode, struct file *file)  
{  
        return 0;  
}  
  
struct file_operations test_fops = {  
read: read_test,  
write: write_test,  
open: open_test,  
release: release_test  
  
};  
  
  
static int hello_init(void)  
{  
        printk(KERN_ALERT "hello, I am Tuotuo\n");  
        int result = 0;  
        result = register_chrdev (0, "test", &test_fops);  
        if(result < 0)  
        {  
                printk(KERN_ALERT "test:can't get major number\n");  
                return result;  
        }  
        if(test_major == 0)  
                test_major = result;  
        printk(KERN_ALERT "test major:%d/r/n", result);  
        return 0;  
}  
  
  
static void hello_exit(void)  
{  
        unregister_chrdev(test_major, "test");  
        printk(KERN_ALERT "googbye Kernel module tuotuo\n");  
}  
  
module_init(hello_init);  
module_exit(hello_exit); 

make 报错 

/data/TestModule2/TestModule.c:26:25: error: ‘UTS_RELEASE’ undeclared here (not in a function)
 char kernel_version[] = UTS_RELEASE;  

[root@openstack01 TestModule2]# grep  'UTS_RELEASE' /usr/src/kernels/3.10.0-514.el7.x86_64/include/generated/utsrelease.h
#define UTS_RELEASE "3.10.0-514.el7.x86_64"

UTS_RELEASE 定义转移到utsrelease.h 文件中 

 cp /usr/src/kernels/3.10.0-514.el7.x86_64/include/generated/utsrelease.h /usr/src/kernels/3.10.0-514.el7.x86_64/include/generated/uapi/linux

添加  #include <linux/utsrelease.h> 

根据打印的

tail -f /var/log/message

Sep 13 11:12:01 localhost kernel: hello, I am Tuotuo
Sep 13 11:12:01 localhost kernel: test major:246/r/n
Sep 13 11:12:01 localhost kernel: test major:246/r/n

[root@openstack01 dev]# mknod test c 246 0

创建字符设备

测试类:

1. [root@localhost module]# cat TestApp.c   
2. #include <stdio.h>  
3. #include <sys/stat.h>  
4. #include <fcntl.h>  
5. int main()  
6. {  
7.         char buf[20] = {0,};  
8.         int i = 0;  
9.         int p = open("/dev/test", O_RDWR);  
10.         if(p == -1)  
11.         {  
12.                 printf("cannot open\n");  
13.                 exit(0);  
14.         }  
15.         printf("buf addr %ui\r\n",buf);  
16.         read(p, buf, 10);  
17.         for(i = 0; i<10; i++)  
18.         {  
19.                 printf("%s\r\n",buf+i);  
20.         }  
21.         close(p);  
22.         return 1;  
23. }  

1. gcc TestApp.c -o TestApp  

打印:

[root@openstack01 TestModule2]# ./TestApp 
buf addr 2882151968i
==========
=========
========
=======
======
=====
====
===
==
=