/******************************************************************************
 * prmigr_back.c
 * 
 * XenLinux process migration tool
 * 
 * Copyright (c) 2005 Anton Korenyushkin tiger@xxxxxxxxxxxxxx
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <asm/uaccess.h>
#include <asm-xen/xen_proc.h>
#include <asm-xen/gnttab.h>
#include <asm-xen/evtchn.h>
#include <asm-xen/xenbus.h>

#define PRMIGR_PROC_FNAME "prmigr"
#define PRMIGR_DIR "/tools"

/* proc file system stuff */

static struct proc_dir_entry *prmigr_proc_file;

static ssize_t prmigr_input(struct file *filp,
			    const char *buff,
			    size_t len,
			    loff_t * off)
{
	int err;

 	err = xenbus_mkdir(PRMIGR_DIR, "prmigr");
	if (err)
		printk(">>>prmigr_back: mkdir failed with %d\n", err);
	else
		printk(">>>prmigr_back: mkdir succeded\n");

	return len;
}


static int prmigr_permission(struct inode *inode, int op, struct nameidata *foo)
{
	if (op == 2 && current->euid == 0)
		return 0;
	return -EACCES;
}

int prmigr_open(struct inode *inode, struct file *file)
{
	try_module_get(THIS_MODULE);
	return 0;
}

int prmigr_close(struct inode *inode, struct file *file)
{
	module_put(THIS_MODULE);
	return 0;		/* success */
}

static struct file_operations prmigr_fops = {
	.write = prmigr_input,
	.open = prmigr_open,
	.release = prmigr_close,
};

static struct inode_operations prmigr_iops = {
	.permission = prmigr_permission,
};


/* Initialisation stuff */

static int __init prmigr_back_init(void)
{
	int ret = 0;

	prmigr_proc_file = create_xen_proc_entry(PRMIGR_PROC_FNAME, 0200);
	prmigr_proc_file->owner = THIS_MODULE;
	prmigr_proc_file->proc_iops = &prmigr_iops;
	prmigr_proc_file->proc_fops = &prmigr_fops;
	prmigr_proc_file->mode = S_IWUSR;
	prmigr_proc_file->uid = 0;
	prmigr_proc_file->gid = 0;
	prmigr_proc_file->size = 0;

	if (prmigr_proc_file == NULL) {
		ret = -ENOMEM;
		remove_xen_proc_entry(PRMIGR_PROC_FNAME);
		/* FIXME */
		printk(KERN_INFO "Error: Could not initialize %s/%s",
		       "/proc/xen",
		       PRMIGR_PROC_FNAME);
	}

	return ret;
}

__initcall(prmigr_back_init);

/*
 * Local variables:
 *  c-file-style: "linux"
 *  indent-tabs-mode: t
 *  c-indent-level: 8
 *  c-basic-offset: 8
 *  tab-width: 8
 * End:
 */