xref: /openbmc/linux/drivers/vfio/vfio.h (revision 9aa2cba7)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (C) 2012 Red Hat, Inc.  All rights reserved.
4  *     Author: Alex Williamson <alex.williamson@redhat.com>
5  */
6 #ifndef __VFIO_VFIO_H__
7 #define __VFIO_VFIO_H__
8 
9 #include <linux/file.h>
10 #include <linux/device.h>
11 #include <linux/cdev.h>
12 #include <linux/module.h>
13 #include <linux/vfio.h>
14 
15 struct iommufd_ctx;
16 struct iommu_group;
17 struct vfio_container;
18 
19 struct vfio_device_file {
20 	struct vfio_device *device;
21 	struct vfio_group *group;
22 
23 	u8 access_granted;
24 	u32 devid; /* only valid when iommufd is valid */
25 	spinlock_t kvm_ref_lock; /* protect kvm field */
26 	struct kvm *kvm;
27 	struct iommufd_ctx *iommufd; /* protected by struct vfio_device_set::lock */
28 };
29 
30 void vfio_device_put_registration(struct vfio_device *device);
31 bool vfio_device_try_get_registration(struct vfio_device *device);
32 int vfio_df_open(struct vfio_device_file *df);
33 void vfio_df_close(struct vfio_device_file *df);
34 struct vfio_device_file *
35 vfio_allocate_device_file(struct vfio_device *device);
36 
37 extern const struct file_operations vfio_device_fops;
38 
39 #ifdef CONFIG_VFIO_NOIOMMU
40 extern bool vfio_noiommu __read_mostly;
41 #else
42 enum { vfio_noiommu = false };
43 #endif
44 
45 enum vfio_group_type {
46 	/*
47 	 * Physical device with IOMMU backing.
48 	 */
49 	VFIO_IOMMU,
50 
51 	/*
52 	 * Virtual device without IOMMU backing. The VFIO core fakes up an
53 	 * iommu_group as the iommu_group sysfs interface is part of the
54 	 * userspace ABI.  The user of these devices must not be able to
55 	 * directly trigger unmediated DMA.
56 	 */
57 	VFIO_EMULATED_IOMMU,
58 
59 	/*
60 	 * Physical device without IOMMU backing. The VFIO core fakes up an
61 	 * iommu_group as the iommu_group sysfs interface is part of the
62 	 * userspace ABI.  Users can trigger unmediated DMA by the device,
63 	 * usage is highly dangerous, requires an explicit opt-in and will
64 	 * taint the kernel.
65 	 */
66 	VFIO_NO_IOMMU,
67 };
68 
69 #if IS_ENABLED(CONFIG_VFIO_GROUP)
70 struct vfio_group {
71 	struct device 			dev;
72 	struct cdev			cdev;
73 	/*
74 	 * When drivers is non-zero a driver is attached to the struct device
75 	 * that provided the iommu_group and thus the iommu_group is a valid
76 	 * pointer. When drivers is 0 the driver is being detached. Once users
77 	 * reaches 0 then the iommu_group is invalid.
78 	 */
79 	refcount_t			drivers;
80 	unsigned int			container_users;
81 	struct iommu_group		*iommu_group;
82 	struct vfio_container		*container;
83 	struct list_head		device_list;
84 	struct mutex			device_lock;
85 	struct list_head		vfio_next;
86 #if IS_ENABLED(CONFIG_VFIO_CONTAINER)
87 	struct list_head		container_next;
88 #endif
89 	enum vfio_group_type		type;
90 	struct mutex			group_lock;
91 	struct kvm			*kvm;
92 	struct file			*opened_file;
93 	struct blocking_notifier_head	notifier;
94 	struct iommufd_ctx		*iommufd;
95 	spinlock_t			kvm_ref_lock;
96 	unsigned int			cdev_device_open_cnt;
97 };
98 
99 int vfio_device_block_group(struct vfio_device *device);
100 void vfio_device_unblock_group(struct vfio_device *device);
101 int vfio_device_set_group(struct vfio_device *device,
102 			  enum vfio_group_type type);
103 void vfio_device_remove_group(struct vfio_device *device);
104 void vfio_device_group_register(struct vfio_device *device);
105 void vfio_device_group_unregister(struct vfio_device *device);
106 int vfio_device_group_use_iommu(struct vfio_device *device);
107 void vfio_device_group_unuse_iommu(struct vfio_device *device);
108 void vfio_df_group_close(struct vfio_device_file *df);
109 struct vfio_group *vfio_group_from_file(struct file *file);
110 bool vfio_group_enforced_coherent(struct vfio_group *group);
111 void vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm);
112 bool vfio_device_has_container(struct vfio_device *device);
113 int __init vfio_group_init(void);
114 void vfio_group_cleanup(void);
115 
116 static inline bool vfio_device_is_noiommu(struct vfio_device *vdev)
117 {
118 	return IS_ENABLED(CONFIG_VFIO_NOIOMMU) &&
119 	       vdev->group->type == VFIO_NO_IOMMU;
120 }
121 #else
122 struct vfio_group;
123 
124 static inline int vfio_device_block_group(struct vfio_device *device)
125 {
126 	return 0;
127 }
128 
129 static inline void vfio_device_unblock_group(struct vfio_device *device)
130 {
131 }
132 
133 static inline int vfio_device_set_group(struct vfio_device *device,
134 					enum vfio_group_type type)
135 {
136 	return 0;
137 }
138 
139 static inline void vfio_device_remove_group(struct vfio_device *device)
140 {
141 }
142 
143 static inline void vfio_device_group_register(struct vfio_device *device)
144 {
145 }
146 
147 static inline void vfio_device_group_unregister(struct vfio_device *device)
148 {
149 }
150 
151 static inline int vfio_device_group_use_iommu(struct vfio_device *device)
152 {
153 	return -EOPNOTSUPP;
154 }
155 
156 static inline void vfio_device_group_unuse_iommu(struct vfio_device *device)
157 {
158 }
159 
160 static inline void vfio_df_group_close(struct vfio_device_file *df)
161 {
162 }
163 
164 static inline struct vfio_group *vfio_group_from_file(struct file *file)
165 {
166 	return NULL;
167 }
168 
169 static inline bool vfio_group_enforced_coherent(struct vfio_group *group)
170 {
171 	return true;
172 }
173 
174 static inline void vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm)
175 {
176 }
177 
178 static inline bool vfio_device_has_container(struct vfio_device *device)
179 {
180 	return false;
181 }
182 
183 static inline int __init vfio_group_init(void)
184 {
185 	return 0;
186 }
187 
188 static inline void vfio_group_cleanup(void)
189 {
190 }
191 
192 static inline bool vfio_device_is_noiommu(struct vfio_device *vdev)
193 {
194 	return false;
195 }
196 #endif /* CONFIG_VFIO_GROUP */
197 
198 #if IS_ENABLED(CONFIG_VFIO_CONTAINER)
199 /**
200  * struct vfio_iommu_driver_ops - VFIO IOMMU driver callbacks
201  */
202 struct vfio_iommu_driver_ops {
203 	char		*name;
204 	struct module	*owner;
205 	void		*(*open)(unsigned long arg);
206 	void		(*release)(void *iommu_data);
207 	long		(*ioctl)(void *iommu_data, unsigned int cmd,
208 				 unsigned long arg);
209 	int		(*attach_group)(void *iommu_data,
210 					struct iommu_group *group,
211 					enum vfio_group_type);
212 	void		(*detach_group)(void *iommu_data,
213 					struct iommu_group *group);
214 	int		(*pin_pages)(void *iommu_data,
215 				     struct iommu_group *group,
216 				     dma_addr_t user_iova,
217 				     int npage, int prot,
218 				     struct page **pages);
219 	void		(*unpin_pages)(void *iommu_data,
220 				       dma_addr_t user_iova, int npage);
221 	void		(*register_device)(void *iommu_data,
222 					   struct vfio_device *vdev);
223 	void		(*unregister_device)(void *iommu_data,
224 					     struct vfio_device *vdev);
225 	int		(*dma_rw)(void *iommu_data, dma_addr_t user_iova,
226 				  void *data, size_t count, bool write);
227 	struct iommu_domain *(*group_iommu_domain)(void *iommu_data,
228 						   struct iommu_group *group);
229 };
230 
231 struct vfio_iommu_driver {
232 	const struct vfio_iommu_driver_ops	*ops;
233 	struct list_head			vfio_next;
234 };
235 
236 int vfio_register_iommu_driver(const struct vfio_iommu_driver_ops *ops);
237 void vfio_unregister_iommu_driver(const struct vfio_iommu_driver_ops *ops);
238 
239 struct vfio_container *vfio_container_from_file(struct file *filep);
240 int vfio_group_use_container(struct vfio_group *group);
241 void vfio_group_unuse_container(struct vfio_group *group);
242 int vfio_container_attach_group(struct vfio_container *container,
243 				struct vfio_group *group);
244 void vfio_group_detach_container(struct vfio_group *group);
245 void vfio_device_container_register(struct vfio_device *device);
246 void vfio_device_container_unregister(struct vfio_device *device);
247 int vfio_device_container_pin_pages(struct vfio_device *device,
248 				    dma_addr_t iova, int npage,
249 				    int prot, struct page **pages);
250 void vfio_device_container_unpin_pages(struct vfio_device *device,
251 				       dma_addr_t iova, int npage);
252 int vfio_device_container_dma_rw(struct vfio_device *device,
253 				 dma_addr_t iova, void *data,
254 				 size_t len, bool write);
255 
256 int __init vfio_container_init(void);
257 void vfio_container_cleanup(void);
258 #else
259 static inline struct vfio_container *
260 vfio_container_from_file(struct file *filep)
261 {
262 	return NULL;
263 }
264 
265 static inline int vfio_group_use_container(struct vfio_group *group)
266 {
267 	return -EOPNOTSUPP;
268 }
269 
270 static inline void vfio_group_unuse_container(struct vfio_group *group)
271 {
272 }
273 
274 static inline int vfio_container_attach_group(struct vfio_container *container,
275 					      struct vfio_group *group)
276 {
277 	return -EOPNOTSUPP;
278 }
279 
280 static inline void vfio_group_detach_container(struct vfio_group *group)
281 {
282 }
283 
284 static inline void vfio_device_container_register(struct vfio_device *device)
285 {
286 }
287 
288 static inline void vfio_device_container_unregister(struct vfio_device *device)
289 {
290 }
291 
292 static inline int vfio_device_container_pin_pages(struct vfio_device *device,
293 						  dma_addr_t iova, int npage,
294 						  int prot, struct page **pages)
295 {
296 	return -EOPNOTSUPP;
297 }
298 
299 static inline void vfio_device_container_unpin_pages(struct vfio_device *device,
300 						     dma_addr_t iova, int npage)
301 {
302 }
303 
304 static inline int vfio_device_container_dma_rw(struct vfio_device *device,
305 					       dma_addr_t iova, void *data,
306 					       size_t len, bool write)
307 {
308 	return -EOPNOTSUPP;
309 }
310 
311 static inline int vfio_container_init(void)
312 {
313 	return 0;
314 }
315 static inline void vfio_container_cleanup(void)
316 {
317 }
318 #endif
319 
320 #if IS_ENABLED(CONFIG_IOMMUFD)
321 bool vfio_iommufd_device_has_compat_ioas(struct vfio_device *vdev,
322 					 struct iommufd_ctx *ictx);
323 int vfio_df_iommufd_bind(struct vfio_device_file *df);
324 void vfio_df_iommufd_unbind(struct vfio_device_file *df);
325 int vfio_iommufd_compat_attach_ioas(struct vfio_device *device,
326 				    struct iommufd_ctx *ictx);
327 #else
328 static inline bool
329 vfio_iommufd_device_has_compat_ioas(struct vfio_device *vdev,
330 				    struct iommufd_ctx *ictx)
331 {
332 	return false;
333 }
334 
335 static inline int vfio_df_iommufd_bind(struct vfio_device_file *fd)
336 {
337 	return -EOPNOTSUPP;
338 }
339 
340 static inline void vfio_df_iommufd_unbind(struct vfio_device_file *df)
341 {
342 }
343 
344 static inline int
345 vfio_iommufd_compat_attach_ioas(struct vfio_device *device,
346 				struct iommufd_ctx *ictx)
347 {
348 	return -EOPNOTSUPP;
349 }
350 #endif
351 
352 int vfio_df_ioctl_attach_pt(struct vfio_device_file *df,
353 			    struct vfio_device_attach_iommufd_pt __user *arg);
354 int vfio_df_ioctl_detach_pt(struct vfio_device_file *df,
355 			    struct vfio_device_detach_iommufd_pt __user *arg);
356 
357 #if IS_ENABLED(CONFIG_VFIO_DEVICE_CDEV)
358 void vfio_init_device_cdev(struct vfio_device *device);
359 
360 static inline int vfio_device_add(struct vfio_device *device)
361 {
362 	/* cdev does not support noiommu device */
363 	if (vfio_device_is_noiommu(device))
364 		return device_add(&device->device);
365 	vfio_init_device_cdev(device);
366 	return cdev_device_add(&device->cdev, &device->device);
367 }
368 
369 static inline void vfio_device_del(struct vfio_device *device)
370 {
371 	if (vfio_device_is_noiommu(device))
372 		device_del(&device->device);
373 	else
374 		cdev_device_del(&device->cdev, &device->device);
375 }
376 
377 int vfio_device_fops_cdev_open(struct inode *inode, struct file *filep);
378 long vfio_df_ioctl_bind_iommufd(struct vfio_device_file *df,
379 				struct vfio_device_bind_iommufd __user *arg);
380 void vfio_df_unbind_iommufd(struct vfio_device_file *df);
381 int vfio_cdev_init(struct class *device_class);
382 void vfio_cdev_cleanup(void);
383 #else
384 static inline void vfio_init_device_cdev(struct vfio_device *device)
385 {
386 }
387 
388 static inline int vfio_device_add(struct vfio_device *device)
389 {
390 	return device_add(&device->device);
391 }
392 
393 static inline void vfio_device_del(struct vfio_device *device)
394 {
395 	device_del(&device->device);
396 }
397 
398 static inline int vfio_device_fops_cdev_open(struct inode *inode,
399 					     struct file *filep)
400 {
401 	return 0;
402 }
403 
404 static inline long vfio_df_ioctl_bind_iommufd(struct vfio_device_file *df,
405 					      struct vfio_device_bind_iommufd __user *arg)
406 {
407 	return -ENOTTY;
408 }
409 
410 static inline void vfio_df_unbind_iommufd(struct vfio_device_file *df)
411 {
412 }
413 
414 static inline int vfio_cdev_init(struct class *device_class)
415 {
416 	return 0;
417 }
418 
419 static inline void vfio_cdev_cleanup(void)
420 {
421 }
422 #endif /* CONFIG_VFIO_DEVICE_CDEV */
423 
424 #if IS_ENABLED(CONFIG_VFIO_VIRQFD)
425 int __init vfio_virqfd_init(void);
426 void vfio_virqfd_exit(void);
427 #else
428 static inline int __init vfio_virqfd_init(void)
429 {
430 	return 0;
431 }
432 static inline void vfio_virqfd_exit(void)
433 {
434 }
435 #endif
436 
437 #ifdef CONFIG_HAVE_KVM
438 void vfio_device_get_kvm_safe(struct vfio_device *device, struct kvm *kvm);
439 void vfio_device_put_kvm(struct vfio_device *device);
440 #else
441 static inline void vfio_device_get_kvm_safe(struct vfio_device *device,
442 					    struct kvm *kvm)
443 {
444 }
445 
446 static inline void vfio_device_put_kvm(struct vfio_device *device)
447 {
448 }
449 #endif
450 
451 #endif
452