// SPDX-License-Identifier: GPL-2.0-only/* * 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> */ #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(struct vfio_device *core_vdev){	struct mdev_device *mdev = to_mdev_device(core_vdev->dev);	struct mdev_parent *parent = mdev->type->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(struct vfio_device *core_vdev){	struct mdev_device *mdev = to_mdev_device(core_vdev->dev);	struct mdev_parent *parent = mdev->type->parent; 	if (likely(parent->ops->release))		parent->ops->release(mdev); 	module_put(THIS_MODULE);} static long vfio_mdev_unlocked_ioctl(struct vfio_device *core_vdev,				     unsigned int cmd, unsigned long arg){	struct mdev_device *mdev = to_mdev_device(core_vdev->dev);	struct mdev_parent *parent = mdev->type->parent; 	if (unlikely(!parent->ops->ioctl))		return -EINVAL; 	return parent->ops->ioctl(mdev, cmd, arg);} static ssize_t vfio_mdev_read(struct vfio_device *core_vdev, char __user *buf,			      size_t count, loff_t *ppos){	struct mdev_device *mdev = to_mdev_device(core_vdev->dev);	struct mdev_parent *parent = mdev->type->parent; 	if (unlikely(!parent->ops->read))		return -EINVAL; 	return parent->ops->read(mdev, buf, count, ppos);} static ssize_t vfio_mdev_write(struct vfio_device *core_vdev,			       const char __user *buf, size_t count,			       loff_t *ppos){	struct mdev_device *mdev = to_mdev_device(core_vdev->dev);	struct mdev_parent *parent = mdev->type->parent; 	if (unlikely(!parent->ops->write))		return -EINVAL; 	return parent->ops->write(mdev, buf, count, ppos);} static int vfio_mdev_mmap(struct vfio_device *core_vdev,			  struct vm_area_struct *vma){	struct mdev_device *mdev = to_mdev_device(core_vdev->dev);	struct mdev_parent *parent = mdev->type->parent; 	if (unlikely(!parent->ops->mmap))		return -EINVAL; 	return parent->ops->mmap(mdev, vma);} static void vfio_mdev_request(struct vfio_device *core_vdev, unsigned int count){	struct mdev_device *mdev = to_mdev_device(core_vdev->dev);	struct mdev_parent *parent = mdev->type->parent; 	if (parent->ops->request)		parent->ops->request(mdev, count);	else if (count == 0)		dev_notice(mdev_dev(mdev),			   "No mdev vendor driver request callback support, blocked until released by user\n");} 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,	.request	= vfio_mdev_request,}; static int vfio_mdev_probe(struct mdev_device *mdev){	struct vfio_device *vdev;	int ret; 	vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);	if (!vdev)		return -ENOMEM; 	vfio_init_group_dev(vdev, &mdev->dev, &vfio_mdev_dev_ops);	ret = vfio_register_group_dev(vdev);	if (ret) {		kfree(vdev);		return ret;	}	dev_set_drvdata(&mdev->dev, vdev);	return 0;} static void vfio_mdev_remove(struct mdev_device *mdev){	struct vfio_device *vdev = dev_get_drvdata(&mdev->dev); 	vfio_unregister_group_dev(vdev);	kfree(vdev);} static struct mdev_driver vfio_mdev_driver = {	.driver = {		.name = "vfio_mdev",		.owner = THIS_MODULE,		.mod_name = KBUILD_MODNAME,	},	.probe	= vfio_mdev_probe,	.remove	= vfio_mdev_remove,}; static int __init vfio_mdev_init(void){	return mdev_register_driver(&vfio_mdev_driver);} 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);