学步园

就不写驱动程序，都忘了怎么去编译了

1  编写源程序hello.c

/*======================================================================

    A simple kernel module: "hello world"

         

    The initial developer of the original code is Baohua Song

    <author@linuxdriver.cn>. All Rights Reserved.

======================================================================*/

#include <linux/init.h>

#include <linux/module.h>

MODULE_LICENSE("Dual BSD/GPL");

static int hello_init(void)

{

  printk(KERN_INFO " Hello World enter\n");

  return 0;

}



static void hello_exit(void)

{

  printk(KERN_INFO " Hello World exit\n ");

}



module_init(hello_init);

module_exit(hello_exit);



MODULE_AUTHOR("Liao Minghua");

MODULE_DESCRIPTION("Hello World Module");

MODULE_ALIAS("hello module");

2 编写Makfle文件

#ifneq ($(KERNELRELEASE),)
obj-m := hello.o
#else
KERNELDIR := /lib/modules/$(shell uname -r)/build
PWD := $(shell pwd)

default:
	$(MAKE) -C $(KERNELDIR) M=$(PWD) modules
#endif

clean:
	rm -f *.ko *.mod.c *.mod.o *.o *.markers *.order *.symvers

3 编译模块

[root@localhost hello]# make

编译过程信息：

make -C /lib/modules/2.6.33.3-85.fc13.i686.PAE/build M=/home/minghua/Documents/code/linuxdriver_code_tool/04/hello modules
make[1]: Entering directory `/usr/src/kernels/2.6.33.3-85.fc13.i686.PAE'
  CC [M]  /home/minghua/Documents/code/linuxdriver_code_tool/04/hello/hello.o
  Building modules, stage 2.
  MODPOST 1 modules
  CC      /home/minghua/Documents/code/linuxdriver_code_tool/04/hello/hello.mod.o
  LD [M]  /home/minghua/Documents/code/linuxdriver_code_tool/04/hello/hello.ko
make[1]: Leaving directory `/usr/src/kernels/2.6.33.3-85.fc13.i686.PAE'

4 装载内核模块

[root@localhost hello]# insmod hello.ko

5 卸载内核模块

[root@localhost hello]# rmmod hello

6 查看内核加载和卸载时的printk的信息

[root@localhost hello]# dmesg | tail -8

输出如下信息：

 Hello World enter
 Hello World exit

注释：dmesg | tail -8 意思是打印内核信息的最后8行