/* * VFIO based driver for Mediated device * * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved. *     Author: Neo Jia <cjia@nvidia.com> *             Kirti Wankhede <kwankhede@nvidia.com> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include <linux/init.h>#include <linux/module.h>#include <linux/device.h>#include <linux/kernel.h>#include <linux/slab.h>#include <linux/vfio.h>#include <linux/mdev.h> #include "mdev_private.h" #define DRIVER_VERSION  "0.1"#define DRIVER_AUTHOR   "NVIDIA Corporation"#define DRIVER_DESC     "VFIO based driver for Mediated device" static int vfio_mdev_open(void *device_data){	struct mdev_device *mdev = device_data;	struct mdev_parent *parent = mdev->parent;	int ret; 	if (unlikely(!parent->ops->open))		return -EINVAL; 	if (!try_module_get(THIS_MODULE))		return -ENODEV; 	ret = parent->ops->open(mdev);	if (ret)		module_put(THIS_MODULE); 	return ret;} static void vfio_mdev_release(void *device_data){	struct mdev_device *mdev = device_data;	struct mdev_parent *parent = mdev->parent; 	if (likely(parent->ops->release))		parent->ops->release(mdev); 	module_put(THIS_MODULE);} static long vfio_mdev_unlocked_ioctl(void *device_data,				     unsigned int cmd, unsigned long arg){	struct mdev_device *mdev = device_data;	struct mdev_parent *parent = mdev->parent; 	if (unlikely(!parent->ops->ioctl))		return -EINVAL; 	return parent->ops->ioctl(mdev, cmd, arg);} static ssize_t vfio_mdev_read(void *device_data, char __user *buf,			      size_t count, loff_t *ppos){	struct mdev_device *mdev = device_data;	struct mdev_parent *parent = mdev->parent; 	if (unlikely(!parent->ops->read))		return -EINVAL; 	return parent->ops->read(mdev, buf, count, ppos);} static ssize_t vfio_mdev_write(void *device_data, const char __user *buf,			       size_t count, loff_t *ppos){	struct mdev_device *mdev = device_data;	struct mdev_parent *parent = mdev->parent; 	if (unlikely(!parent->ops->write))		return -EINVAL; 	return parent->ops->write(mdev, buf, count, ppos);} static int vfio_mdev_mmap(void *device_data, struct vm_area_struct *vma){	struct mdev_device *mdev = device_data;	struct mdev_parent *parent = mdev->parent; 	if (unlikely(!parent->ops->mmap))		return -EINVAL; 	return parent->ops->mmap(mdev, vma);} static const struct vfio_device_ops vfio_mdev_dev_ops = {	.name		= "vfio-mdev",	.open		= vfio_mdev_open,	.release	= vfio_mdev_release,	.ioctl		= vfio_mdev_unlocked_ioctl,	.read		= vfio_mdev_read,	.write		= vfio_mdev_write,	.mmap		= vfio_mdev_mmap,}; int vfio_mdev_probe(struct device *dev){	struct mdev_device *mdev = to_mdev_device(dev); 	return vfio_add_group_dev(dev, &vfio_mdev_dev_ops, mdev);} void vfio_mdev_remove(struct device *dev){	vfio_del_group_dev(dev);} struct mdev_driver vfio_mdev_driver = {	.name	= "vfio_mdev",	.probe	= vfio_mdev_probe,	.remove	= vfio_mdev_remove,}; static int __init vfio_mdev_init(void){	return mdev_register_driver(&vfio_mdev_driver, THIS_MODULE);} static void __exit vfio_mdev_exit(void){	mdev_unregister_driver(&vfio_mdev_driver);} module_init(vfio_mdev_init)module_exit(vfio_mdev_exit) MODULE_VERSION(DRIVER_VERSION);MODULE_LICENSE("GPL v2");MODULE_AUTHOR(DRIVER_AUTHOR);MODULE_DESCRIPTION(DRIVER_DESC);