第一人入门字符设备驱动程序的问题
在Linux高级开发技术里面,第二章学了一点内核驱动,虽然里面排版巨烂,但勉强能很懂
按照它的程序,自己敲到机子上之后,编译总是能不过,提示
struct file_opterations有错不知道为啥,是不是结构体有问题???
请大虾看一下源码:
#include <linux/types.h>
#include <linux/fs.h>
#include <linux/errno.h>
#define DEFAULT 0
unsigned int dev_major = 0;
static int dev_read(struct inode *node,struct file*file,char* buf,int i)
{
int a,b;
char* c = "hello ";
int j;
if(verify_area(VERIFY_WRITE,buf,i) == DEFAULT)
return DEFAULT;
/*get_user(a,int(buf[0]));
get_user(b,int(buf[1]));
a = a+b;
*/
for(j = 0;j <i;j++)
{
buf[j] = c[j];
}
return i;
}
static int dev_write(struct inode *node,struct file*file,const char* buf,int count)
{
return count;
}
static int dev_open(struct inode *node,struct file*file)
{
/*MOD_INC_USE_COUNT;*/
return 0;
}
static void dev_release(struct inode *node,struct file*file)
{
/*MOD_DEC_USE_COUNT;*/
}
struct file_operations dev_fops = {
NULL,dev_read,dev_write,NULL,
NULL,NULL,NULL,dev_open,
dev_release,NULL,NULL,NULL,NULL
};
int init_module()
{
int result;
result = register_chrdev(0, "test ",&dev_fops);
if(result < 0)
{
printk( "Wrong! ");
return result;
}
if(dev_major == 0)
dev_major = result;
return 0;
}
void cleanup_module()
{
unregister_chrdev(dev_major, "mydev ");
}
应用程序的main函数:
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
main()
{
int ret;
int buf[10];
ret = open( "/dev/mydev ",O_RDWR);
if(ret == -1)
{
printf( "cann 't open mydev ");
exit(0);
}
/*printf( "please input two number! ");
scanf( "%d ",buf);
scanf( "%d ",buf+1);*/
read(ret,buf,1);
printf( "the result is:%s ",buf);
close(ret);
}
帮忙看下,有什么问题
还有呀,就是内核函数怎么查询???
用man put_user说查不到此函数,用man 2 put_user也查不到
不知道有什么手册没???
谢了
[解决办法]
struct file_operations dev_fops = {
NULL,dev_read,dev_write,NULL,
NULL,NULL,NULL,dev_open,
dev_release,NULL,NULL,NULL,NULL
};
改成下面这个试试
struct file_operations dev_fops ={
read: dev_read,
write: dev_write,
open: dev_open,
release:dev_release
};
[解决办法]
内核函数怎么查询???
建议楼主装一下SOURCE INSIGHT,然后建个工程,直接把LINUX内核代码添加进去~~~
以后直接查找就可以了~~~