tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2021-2022, NVIDIA CORPORATION & AFFILIATES
4 */
5#include <linux/vfio.h>
6#include <linux/iommufd.h>
7
8#include "vfio.h"
9
10MODULE_IMPORT_NS(IOMMUFD);
11MODULE_IMPORT_NS(IOMMUFD_VFIO);
12
13int vfio_iommufd_bind(struct vfio_device *vdev, struct iommufd_ctx *ictx)
14{
15 u32 ioas_id;
16 u32 device_id;
17 int ret;
18
19 lockdep_assert_held(&vdev->dev_set->lock);
20
21 /*
22 * If the driver doesn't provide this op then it means the device does
23 * not do DMA at all. So nothing to do.
24 */
25 if (!vdev->ops->bind_iommufd)
26 return 0;
27
28 ret = vdev->ops->bind_iommufd(vdev, ictx, &device_id);
29 if (ret)
30 return ret;
31
32 ret = iommufd_vfio_compat_ioas_id(ictx, &ioas_id);
33 if (ret)
34 goto err_unbind;
35 ret = vdev->ops->attach_ioas(vdev, &ioas_id);
36 if (ret)
37 goto err_unbind;
38
39 /*
40 * The legacy path has no way to return the device id or the selected
41 * pt_id
42 */
43 return 0;
44
45err_unbind:
46 if (vdev->ops->unbind_iommufd)
47 vdev->ops->unbind_iommufd(vdev);
48 return ret;
49}
50
51void vfio_iommufd_unbind(struct vfio_device *vdev)
52{
53 lockdep_assert_held(&vdev->dev_set->lock);
54
55 if (vdev->ops->unbind_iommufd)
56 vdev->ops->unbind_iommufd(vdev);
57}
58
59/*
60 * The physical standard ops mean that the iommufd_device is bound to the
61 * physical device vdev->dev that was provided to vfio_init_group_dev(). Drivers
62 * using this ops set should call vfio_register_group_dev()
63 */
64int vfio_iommufd_physical_bind(struct vfio_device *vdev,
65 struct iommufd_ctx *ictx, u32 *out_device_id)
66{
67 struct iommufd_device *idev;
68
69 idev = iommufd_device_bind(ictx, vdev->dev, out_device_id);
70 if (IS_ERR(idev))
71 return PTR_ERR(idev);
72 vdev->iommufd_device = idev;
73 return 0;
74}
75EXPORT_SYMBOL_GPL(vfio_iommufd_physical_bind);
76
77void vfio_iommufd_physical_unbind(struct vfio_device *vdev)
78{
79 lockdep_assert_held(&vdev->dev_set->lock);
80
81 if (vdev->iommufd_attached) {
82 iommufd_device_detach(vdev->iommufd_device);
83 vdev->iommufd_attached = false;
84 }
85 iommufd_device_unbind(vdev->iommufd_device);
86 vdev->iommufd_device = NULL;
87}
88EXPORT_SYMBOL_GPL(vfio_iommufd_physical_unbind);
89
90int vfio_iommufd_physical_attach_ioas(struct vfio_device *vdev, u32 *pt_id)
91{
92 int rc;
93
94 rc = iommufd_device_attach(vdev->iommufd_device, pt_id);
95 if (rc)
96 return rc;
97 vdev->iommufd_attached = true;
98 return 0;
99}
100EXPORT_SYMBOL_GPL(vfio_iommufd_physical_attach_ioas);
101
102/*
103 * The emulated standard ops mean that vfio_device is going to use the
104 * "mdev path" and will call vfio_pin_pages()/vfio_dma_rw(). Drivers using this
105 * ops set should call vfio_register_emulated_iommu_dev().
106 */
107
108static void vfio_emulated_unmap(void *data, unsigned long iova,
109 unsigned long length)
110{
111 struct vfio_device *vdev = data;
112
113 vdev->ops->dma_unmap(vdev, iova, length);
114}
115
116static const struct iommufd_access_ops vfio_user_ops = {
117 .needs_pin_pages = 1,
118 .unmap = vfio_emulated_unmap,
119};
120
121int vfio_iommufd_emulated_bind(struct vfio_device *vdev,
122 struct iommufd_ctx *ictx, u32 *out_device_id)
123{
124 lockdep_assert_held(&vdev->dev_set->lock);
125
126 vdev->iommufd_ictx = ictx;
127 iommufd_ctx_get(ictx);
128 return 0;
129}
130EXPORT_SYMBOL_GPL(vfio_iommufd_emulated_bind);
131
132void vfio_iommufd_emulated_unbind(struct vfio_device *vdev)
133{
134 lockdep_assert_held(&vdev->dev_set->lock);
135
136 if (vdev->iommufd_access) {
137 iommufd_access_destroy(vdev->iommufd_access);
138 vdev->iommufd_access = NULL;
139 }
140 iommufd_ctx_put(vdev->iommufd_ictx);
141 vdev->iommufd_ictx = NULL;
142}
143EXPORT_SYMBOL_GPL(vfio_iommufd_emulated_unbind);
144
145int vfio_iommufd_emulated_attach_ioas(struct vfio_device *vdev, u32 *pt_id)
146{
147 struct iommufd_access *user;
148
149 lockdep_assert_held(&vdev->dev_set->lock);
150
151 user = iommufd_access_create(vdev->iommufd_ictx, *pt_id, &vfio_user_ops,
152 vdev);
153 if (IS_ERR(user))
154 return PTR_ERR(user);
155 vdev->iommufd_access = user;
156 return 0;
157}
158EXPORT_SYMBOL_GPL(vfio_iommufd_emulated_attach_ioas);