summaryrefslogtreecommitdiff
path: root/drivers/vfio/iommufd.c
blob: 4f82a6fa7c6c7fcc25da29c4a497ee673f34d618 (plain) (blame)
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
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2021-2022, NVIDIA CORPORATION & AFFILIATES
 */
#include <linux/vfio.h>
#include <linux/iommufd.h>

#include "vfio.h"

MODULE_IMPORT_NS(IOMMUFD);
MODULE_IMPORT_NS(IOMMUFD_VFIO);

int vfio_iommufd_bind(struct vfio_device *vdev, struct iommufd_ctx *ictx)
{
	u32 ioas_id;
	u32 device_id;
	int ret;

	lockdep_assert_held(&vdev->dev_set->lock);

	/*
	 * If the driver doesn't provide this op then it means the device does
	 * not do DMA at all. So nothing to do.
	 */
	if (!vdev->ops->bind_iommufd)
		return 0;

	ret = vdev->ops->bind_iommufd(vdev, ictx, &device_id);
	if (ret)
		return ret;

	ret = iommufd_vfio_compat_ioas_id(ictx, &ioas_id);
	if (ret)
		goto err_unbind;
	ret = vdev->ops->attach_ioas(vdev, &ioas_id);
	if (ret)
		goto err_unbind;

	/*
	 * The legacy path has no way to return the device id or the selected
	 * pt_id
	 */
	return 0;

err_unbind:
	if (vdev->ops->unbind_iommufd)
		vdev->ops->unbind_iommufd(vdev);
	return ret;
}

void vfio_iommufd_unbind(struct vfio_device *vdev)
{
	lockdep_assert_held(&vdev->dev_set->lock);

	if (vdev->ops->unbind_iommufd)
		vdev->ops->unbind_iommufd(vdev);
}

/*
 * The physical standard ops mean that the iommufd_device is bound to the
 * physical device vdev->dev that was provided to vfio_init_group_dev(). Drivers
 * using this ops set should call vfio_register_group_dev()
 */
int vfio_iommufd_physical_bind(struct vfio_device *vdev,
			       struct iommufd_ctx *ictx, u32 *out_device_id)
{
	struct iommufd_device *idev;

	idev = iommufd_device_bind(ictx, vdev->dev, out_device_id);
	if (IS_ERR(idev))
		return PTR_ERR(idev);
	vdev->iommufd_device = idev;
	return 0;
}
EXPORT_SYMBOL_GPL(vfio_iommufd_physical_bind);

void vfio_iommufd_physical_unbind(struct vfio_device *vdev)
{
	lockdep_assert_held(&vdev->dev_set->lock);

	if (vdev->iommufd_attached) {
		iommufd_device_detach(vdev->iommufd_device);
		vdev->iommufd_attached = false;
	}
	iommufd_device_unbind(vdev->iommufd_device);
	vdev->iommufd_device = NULL;
}
EXPORT_SYMBOL_GPL(vfio_iommufd_physical_unbind);

int vfio_iommufd_physical_attach_ioas(struct vfio_device *vdev, u32 *pt_id)
{
	int rc;

	rc = iommufd_device_attach(vdev->iommufd_device, pt_id);
	if (rc)
		return rc;
	vdev->iommufd_attached = true;
	return 0;
}
EXPORT_SYMBOL_GPL(vfio_iommufd_physical_attach_ioas);

/*
 * The emulated standard ops mean that vfio_device is going to use the
 * "mdev path" and will call vfio_pin_pages()/vfio_dma_rw(). Drivers using this
 * ops set should call vfio_register_emulated_iommu_dev().
 */

static void vfio_emulated_unmap(void *data, unsigned long iova,
				unsigned long length)
{
	struct vfio_device *vdev = data;

	vdev->ops->dma_unmap(vdev, iova, length);
}

static const struct iommufd_access_ops vfio_user_ops = {
	.needs_pin_pages = 1,
	.unmap = vfio_emulated_unmap,
};

int vfio_iommufd_emulated_bind(struct vfio_device *vdev,
			       struct iommufd_ctx *ictx, u32 *out_device_id)
{
	lockdep_assert_held(&vdev->dev_set->lock);

	vdev->iommufd_ictx = ictx;
	iommufd_ctx_get(ictx);
	return 0;
}
EXPORT_SYMBOL_GPL(vfio_iommufd_emulated_bind);

void vfio_iommufd_emulated_unbind(struct vfio_device *vdev)
{
	lockdep_assert_held(&vdev->dev_set->lock);

	if (vdev->iommufd_access) {
		iommufd_access_destroy(vdev->iommufd_access);
		vdev->iommufd_access = NULL;
	}
	iommufd_ctx_put(vdev->iommufd_ictx);
	vdev->iommufd_ictx = NULL;
}
EXPORT_SYMBOL_GPL(vfio_iommufd_emulated_unbind);

int vfio_iommufd_emulated_attach_ioas(struct vfio_device *vdev, u32 *pt_id)
{
	struct iommufd_access *user;

	lockdep_assert_held(&vdev->dev_set->lock);

	user = iommufd_access_create(vdev->iommufd_ictx, *pt_id, &vfio_user_ops,
				     vdev);
	if (IS_ERR(user))
		return PTR_ERR(user);
	vdev->iommufd_access = user;
	return 0;
}
EXPORT_SYMBOL_GPL(vfio_iommufd_emulated_attach_ioas);