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
10 MODULE_IMPORT_NS("IOMMUFD");
11 MODULE_IMPORT_NS("IOMMUFD_VFIO");
12
vfio_iommufd_device_has_compat_ioas(struct vfio_device * vdev,struct iommufd_ctx * ictx)13 bool vfio_iommufd_device_has_compat_ioas(struct vfio_device *vdev,
14 struct iommufd_ctx *ictx)
15 {
16 u32 ioas_id;
17
18 return !iommufd_vfio_compat_ioas_get_id(ictx, &ioas_id);
19 }
20
vfio_df_iommufd_bind(struct vfio_device_file * df)21 int vfio_df_iommufd_bind(struct vfio_device_file *df)
22 {
23 struct vfio_device *vdev = df->device;
24 struct iommufd_ctx *ictx = df->iommufd;
25
26 lockdep_assert_held(&vdev->dev_set->lock);
27
28 return vdev->ops->bind_iommufd(vdev, ictx, &df->devid);
29 }
30
vfio_iommufd_compat_attach_ioas(struct vfio_device * vdev,struct iommufd_ctx * ictx)31 int vfio_iommufd_compat_attach_ioas(struct vfio_device *vdev,
32 struct iommufd_ctx *ictx)
33 {
34 u32 ioas_id;
35 int ret;
36
37 lockdep_assert_held(&vdev->dev_set->lock);
38
39 /* compat noiommu does not need to do ioas attach */
40 if (vfio_device_is_noiommu(vdev))
41 return 0;
42
43 ret = iommufd_vfio_compat_ioas_get_id(ictx, &ioas_id);
44 if (ret)
45 return ret;
46
47 /* The legacy path has no way to return the selected pt_id */
48 return vdev->ops->attach_ioas(vdev, &ioas_id);
49 }
50
vfio_df_iommufd_unbind(struct vfio_device_file * df)51 void vfio_df_iommufd_unbind(struct vfio_device_file *df)
52 {
53 struct vfio_device *vdev = df->device;
54
55 lockdep_assert_held(&vdev->dev_set->lock);
56
57 if (vfio_device_is_noiommu(vdev))
58 return;
59
60 if (vdev->ops->unbind_iommufd)
61 vdev->ops->unbind_iommufd(vdev);
62 }
63
vfio_iommufd_device_ictx(struct vfio_device * vdev)64 struct iommufd_ctx *vfio_iommufd_device_ictx(struct vfio_device *vdev)
65 {
66 if (vdev->iommufd_device)
67 return iommufd_device_to_ictx(vdev->iommufd_device);
68 return NULL;
69 }
70 EXPORT_SYMBOL_GPL(vfio_iommufd_device_ictx);
71
vfio_iommufd_device_id(struct vfio_device * vdev)72 static int vfio_iommufd_device_id(struct vfio_device *vdev)
73 {
74 if (vdev->iommufd_device)
75 return iommufd_device_to_id(vdev->iommufd_device);
76 return -EINVAL;
77 }
78
79 /*
80 * Return devid for a device.
81 * valid ID for the device that is owned by the ictx
82 * -ENOENT = device is owned but there is no ID
83 * -ENODEV or other error = device is not owned
84 */
vfio_iommufd_get_dev_id(struct vfio_device * vdev,struct iommufd_ctx * ictx)85 int vfio_iommufd_get_dev_id(struct vfio_device *vdev, struct iommufd_ctx *ictx)
86 {
87 struct iommu_group *group;
88 int devid;
89
90 if (vfio_iommufd_device_ictx(vdev) == ictx)
91 return vfio_iommufd_device_id(vdev);
92
93 group = iommu_group_get(vdev->dev);
94 if (!group)
95 return -ENODEV;
96
97 if (iommufd_ctx_has_group(ictx, group))
98 devid = -ENOENT;
99 else
100 devid = -ENODEV;
101
102 iommu_group_put(group);
103
104 return devid;
105 }
106 EXPORT_SYMBOL_GPL(vfio_iommufd_get_dev_id);
107
108 /*
109 * The physical standard ops mean that the iommufd_device is bound to the
110 * physical device vdev->dev that was provided to vfio_init_group_dev(). Drivers
111 * using this ops set should call vfio_register_group_dev()
112 */
vfio_iommufd_physical_bind(struct vfio_device * vdev,struct iommufd_ctx * ictx,u32 * out_device_id)113 int vfio_iommufd_physical_bind(struct vfio_device *vdev,
114 struct iommufd_ctx *ictx, u32 *out_device_id)
115 {
116 struct iommufd_device *idev;
117
118 idev = iommufd_device_bind(ictx, vdev->dev, out_device_id);
119 if (IS_ERR(idev))
120 return PTR_ERR(idev);
121 vdev->iommufd_device = idev;
122 return 0;
123 }
124 EXPORT_SYMBOL_GPL(vfio_iommufd_physical_bind);
125
vfio_iommufd_physical_unbind(struct vfio_device * vdev)126 void vfio_iommufd_physical_unbind(struct vfio_device *vdev)
127 {
128 lockdep_assert_held(&vdev->dev_set->lock);
129
130 if (vdev->iommufd_attached) {
131 iommufd_device_detach(vdev->iommufd_device);
132 vdev->iommufd_attached = false;
133 }
134 iommufd_device_unbind(vdev->iommufd_device);
135 vdev->iommufd_device = NULL;
136 }
137 EXPORT_SYMBOL_GPL(vfio_iommufd_physical_unbind);
138
vfio_iommufd_physical_attach_ioas(struct vfio_device * vdev,u32 * pt_id)139 int vfio_iommufd_physical_attach_ioas(struct vfio_device *vdev, u32 *pt_id)
140 {
141 int rc;
142
143 lockdep_assert_held(&vdev->dev_set->lock);
144
145 if (WARN_ON(!vdev->iommufd_device))
146 return -EINVAL;
147
148 if (vdev->iommufd_attached)
149 rc = iommufd_device_replace(vdev->iommufd_device, pt_id);
150 else
151 rc = iommufd_device_attach(vdev->iommufd_device, pt_id);
152 if (rc)
153 return rc;
154 vdev->iommufd_attached = true;
155 return 0;
156 }
157 EXPORT_SYMBOL_GPL(vfio_iommufd_physical_attach_ioas);
158
vfio_iommufd_physical_detach_ioas(struct vfio_device * vdev)159 void vfio_iommufd_physical_detach_ioas(struct vfio_device *vdev)
160 {
161 lockdep_assert_held(&vdev->dev_set->lock);
162
163 if (WARN_ON(!vdev->iommufd_device) || !vdev->iommufd_attached)
164 return;
165
166 iommufd_device_detach(vdev->iommufd_device);
167 vdev->iommufd_attached = false;
168 }
169 EXPORT_SYMBOL_GPL(vfio_iommufd_physical_detach_ioas);
170
171 /*
172 * The emulated standard ops mean that vfio_device is going to use the
173 * "mdev path" and will call vfio_pin_pages()/vfio_dma_rw(). Drivers using this
174 * ops set should call vfio_register_emulated_iommu_dev(). Drivers that do
175 * not call vfio_pin_pages()/vfio_dma_rw() have no need to provide dma_unmap.
176 */
177
vfio_emulated_unmap(void * data,unsigned long iova,unsigned long length)178 static void vfio_emulated_unmap(void *data, unsigned long iova,
179 unsigned long length)
180 {
181 struct vfio_device *vdev = data;
182
183 if (vdev->ops->dma_unmap)
184 vdev->ops->dma_unmap(vdev, iova, length);
185 }
186
187 static const struct iommufd_access_ops vfio_user_ops = {
188 .needs_pin_pages = 1,
189 .unmap = vfio_emulated_unmap,
190 };
191
vfio_iommufd_emulated_bind(struct vfio_device * vdev,struct iommufd_ctx * ictx,u32 * out_device_id)192 int vfio_iommufd_emulated_bind(struct vfio_device *vdev,
193 struct iommufd_ctx *ictx, u32 *out_device_id)
194 {
195 struct iommufd_access *user;
196
197 lockdep_assert_held(&vdev->dev_set->lock);
198
199 user = iommufd_access_create(ictx, &vfio_user_ops, vdev, out_device_id);
200 if (IS_ERR(user))
201 return PTR_ERR(user);
202 vdev->iommufd_access = user;
203 return 0;
204 }
205 EXPORT_SYMBOL_GPL(vfio_iommufd_emulated_bind);
206
vfio_iommufd_emulated_unbind(struct vfio_device * vdev)207 void vfio_iommufd_emulated_unbind(struct vfio_device *vdev)
208 {
209 lockdep_assert_held(&vdev->dev_set->lock);
210
211 if (vdev->iommufd_access) {
212 iommufd_access_destroy(vdev->iommufd_access);
213 vdev->iommufd_attached = false;
214 vdev->iommufd_access = NULL;
215 }
216 }
217 EXPORT_SYMBOL_GPL(vfio_iommufd_emulated_unbind);
218
vfio_iommufd_emulated_attach_ioas(struct vfio_device * vdev,u32 * pt_id)219 int vfio_iommufd_emulated_attach_ioas(struct vfio_device *vdev, u32 *pt_id)
220 {
221 int rc;
222
223 lockdep_assert_held(&vdev->dev_set->lock);
224
225 if (vdev->iommufd_attached)
226 rc = iommufd_access_replace(vdev->iommufd_access, *pt_id);
227 else
228 rc = iommufd_access_attach(vdev->iommufd_access, *pt_id);
229 if (rc)
230 return rc;
231 vdev->iommufd_attached = true;
232 return 0;
233 }
234 EXPORT_SYMBOL_GPL(vfio_iommufd_emulated_attach_ioas);
235
vfio_iommufd_emulated_detach_ioas(struct vfio_device * vdev)236 void vfio_iommufd_emulated_detach_ioas(struct vfio_device *vdev)
237 {
238 lockdep_assert_held(&vdev->dev_set->lock);
239
240 if (WARN_ON(!vdev->iommufd_access) ||
241 !vdev->iommufd_attached)
242 return;
243
244 iommufd_access_detach(vdev->iommufd_access);
245 vdev->iommufd_attached = false;
246 }
247 EXPORT_SYMBOL_GPL(vfio_iommufd_emulated_detach_ioas);
248