procインターフェース

Makefile

obj-m = proctest.o
KVERSION = $(shell uname -r)
all:
	make -C /lib/modules/$(KVERSION)/build M=$(PWD) modules
clean:
	make -C /lib/modules/$(KVERSION)/build M=$(PWD) clean

proctest.c

/*
* 基本的に下のURLのパクリ
* http://d.hatena.ne.jp/masami256/20100315/1268662409
* create_proc_entry -> proc_create が主な変更
*/

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/fs.h>
#include <linux/proc_fs.h>
#include <linux/stat.h>
#include <linux/string.h>
#include <asm/uaccess.h>


MODULE_DESCRIPTION("proc file system test");
MODULE_LICENSE("GPL");

static const char const module_name[] = "proc_test";

static int proc_test_read(struct file *file, char __user *buf, size_t size, loff_t *ppos);

static int proc_test_write(struct file *file, const char __user *buf, size_t size, loff_t *ppos);

static struct file_operations proctest_fop = {
	.read = proc_test_read,
	.write = proc_test_write,
};

static struct proc_dir_entry *pdir_entry;

static int proc_test_init(void)
{
	printk(KERN_INFO "%s\n", __FUNCTION__);

//	pdir_entry = create_proc_entry(module_name, 0644, NULL);
//	kernel 3.10では使えない?
	pdir_entry = proc_create(module_name, 0644, NULL, &proctest_fop);
	if (!pdir_entry) {
		remove_proc_entry(module_name, NULL);
		return -EFAULT;
	}

//	pdir_entry->mode = S_IRUGO;
//	pdir_entry->gid = 0;
//	pdir_entry->uid = 0;
//	pdir_entry->read_proc = (read_proc_t *) proc_test_read;
//	pdir_entry->write_proc = (write_proc_t *) proc_test_write;

	return 0;
}

static void proc_test_cleanup(void)
{
	printk(KERN_INFO "%s\n", __FUNCTION__);
	remove_proc_entry(module_name, NULL);
}

static char proc_test_buf[256] = "Hello, World";

static int proc_test_read(struct file *file, char __user *buf, size_t size, loff_t *ppos)
{
	if (*ppos >= 256)
		return -EINVAL;
	if (*ppos + size > 256)
		size = 256 - *ppos;

	if (!buf)
		return -EINVAL;

	size = snprintf(buf, size, "%s", proc_test_buf + *ppos);
	*ppos += size;

	return size;
}


static int proc_test_write(struct file *file, const char __user *buf, size_t size, loff_t *ppos)
{
	if (*ppos >= 256)
		return -EINVAL;
	if (*ppos + size > 256)
		size = 256 - *ppos;

	if (!buf)
		return -EINVAL;
	
	memset(proc_test_buf, 0x0, sizeof(proc_test_buf));
	if (copy_from_user(proc_test_buf + *ppos, buf, size))
		return -EFAULT;

	return size;
}


module_init(proc_test_init);
module_exit(proc_test_cleanup);