summaryrefslogtreecommitdiff
path: root/drivers/vfio/mdev/vfio_mdev.c
blob: 4043cc91f9524eeda64d4506fc8fd83a537a1291 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
// 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(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 void vfio_mdev_request(void *device_data, unsigned int count)
{
	struct mdev_device *mdev = device_data;
	struct mdev_parent *parent = mdev->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 device *dev)
{
	struct mdev_device *mdev = to_mdev_device(dev);
	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, mdev);
	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 device *dev)
{
	struct vfio_device *vdev = dev_get_drvdata(dev);

	vfio_unregister_group_dev(vdev);
	kfree(vdev);
}

static 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);