fpgafs/fpgafs_lldrv_dbg.c

/*********************************************
 * Benjamin Krill <ben@codiert.org>
 *********************************************/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/pagemap.h>
#include <linux/mm.h>
#include "fpgafs.h"

static int load = 0;
static unsigned char *load_buf;

static int fpgafs_send_data_dbg(const char __user *buf, int len)
{
	printk("fpgafs: send data DEBUG\n");
	return 0;
}

static int fpgafs_recv_data_dbg(unsigned char *buf, int len)
{
	printk("fpgafs: receive data DEBUG\n");
	return 4;
}

static int fpgafs_read_load_dbg(unsigned char *buf, int len)
{
	if (load == 0)
		return -EBUSY;

	len = len > sizeof(load_buf)?sizeof(load_buf):len;

	if (copy_to_user(buf, load_buf, len))
		return -EFAULT;

	return len;
}

static int fpgafs_write_load_dbg(const char __user *buf, int len)
{
	u32 cp = 0;
	u8 __user *usr;

	if (load == 1)
		return -EBUSY;

	if (len < 2)
		return -EINVAL;

	if (!access_ok(VERIFY_READ, buf, len))
		return -EFAULT;

	load_buf = kmalloc(len,GFP_USER);

	while (cp < len) {
		usr = (u8*)&buf[cp];
		if (__get_user(load_buf[cp], usr))
			return -EFAULT;
		cp++;
	}

	load = 1;
	return len;
}

static struct fpgafs_lldrv fpgafs_lldrv_dbg = {
	.name = "dbg",
	.init = NULL,
	.exit = NULL,
	.send = &fpgafs_send_data_dbg,
	.recv = &fpgafs_recv_data_dbg,
	.read_load = &fpgafs_read_load_dbg,
	.write_load = &fpgafs_write_load_dbg,
};

/* init exit functions ... */
int __init fpgafs_lldrv_dbg_init(void)
{
	return fpgafs_register_lldrv(&fpgafs_lldrv_dbg);
}

void __exit fpgafs_lldrv_dbg_exit(void)
{
	load = 0;
	kfree(load_buf);
	fpgafs_unregister_lldrv(&fpgafs_lldrv_dbg);
}

module_init(fpgafs_lldrv_dbg_init);
module_exit(fpgafs_lldrv_dbg_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Benjamin Krill <ben@codiert.org>");