module.c

来自「在linux下使用c语言编写的一个文件拷贝的源码」· C语言 代码 · 共 76 行

#include <linux/module.h>
#include <linux/config.h>
#include <linux/version.h>
#include <linux/types.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/errno.h>
#include <asm/segment.h>
unsigned int test_major = 0;
char kernel_version[] = UTS_RELEASE;

static ssize_t read_test(struct file *file, char *buf, size_t size,
			 loff_t * loff)
{
    printk("<0>Hello!This is the program written by Nick Cen.\n");
    return size;
}

static ssize_t write_test(struct file *file, const char *buf, size_t size,
			  loff_t * loff)
{
    return size;
}

static int open_test(struct inode *inode, struct file *file)
{
    MOD_INC_USE_COUNT;
    return 0;
}

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


struct file_operations test_fops = {
    NULL,
    NULL,
    read_test,
    write_test,
    NULL,
    NULL,
    NULL,
    NULL,
    open_test,
    NULL,
    release_test,
    NULL,
    NULL,
    NULL,
    NULL,
    NULL,
    NULL,
    NULL,
};

int init_module(void)
{
    int result;
    result = register_chrdev(0, "test", &test_fops);
    if (result < 0) {
	printk(KERN_INFO "test: can't get major number\n");
	return result;
    }
    if (test_major == 0)
	test_major = result;	/* dynamic */
    return 0;
}

void cleanup_module(void)
{
    unregister_chrdev(test_major, "test");
}