1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * VFIO API definition
4 *
5 * Copyright (C) 2012 Red Hat, Inc. All rights reserved.
6 * Author: Alex Williamson <alex.williamson@redhat.com>
7 */
8 #ifndef VFIO_H
9 #define VFIO_H
10
11
12 #include <linux/iommu.h>
13 #include <linux/mm.h>
14 #include <linux/workqueue.h>
15 #include <linux/poll.h>
16 #include <linux/cdev.h>
17 #include <uapi/linux/vfio.h>
18 #include <linux/iova_bitmap.h>
19
20 struct kvm;
21 struct iommufd_ctx;
22 struct iommufd_device;
23 struct iommufd_access;
24 struct vfio_info_cap;
25
26 /*
27 * VFIO devices can be placed in a set, this allows all devices to share this
28 * structure and the VFIO core will provide a lock that is held around
29 * open_device()/close_device() for all devices in the set.
30 */
31 struct vfio_device_set {
32 void *set_id;
33 struct mutex lock;
34 struct list_head device_list;
35 unsigned int device_count;
36 };
37
38 struct vfio_device {
39 struct device *dev;
40 const struct vfio_device_ops *ops;
41 /*
42 * mig_ops/log_ops is a static property of the vfio_device which must
43 * be set prior to registering the vfio_device.
44 */
45 const struct vfio_migration_ops *mig_ops;
46 const struct vfio_log_ops *log_ops;
47 #if IS_ENABLED(CONFIG_VFIO_GROUP)
48 struct vfio_group *group;
49 struct list_head group_next;
50 struct list_head iommu_entry;
51 #endif
52 struct vfio_device_set *dev_set;
53 struct list_head dev_set_list;
54 unsigned int migration_flags;
55 struct kvm *kvm;
56
57 /* Members below here are private, not for driver use */
58 unsigned int index;
59 struct device device; /* device.kref covers object life circle */
60 #if IS_ENABLED(CONFIG_VFIO_DEVICE_CDEV)
61 struct cdev cdev;
62 #endif
63 refcount_t refcount; /* user count on registered device*/
64 unsigned int open_count;
65 struct completion comp;
66 struct iommufd_access *iommufd_access;
67 void (*put_kvm)(struct kvm *kvm);
68 struct inode *inode;
69 #if IS_ENABLED(CONFIG_IOMMUFD)
70 struct iommufd_device *iommufd_device;
71 struct ida pasids;
72 u8 iommufd_attached:1;
73 #endif
74 u8 cdev_opened:1;
75 #ifdef CONFIG_DEBUG_FS
76 /*
77 * debug_root is a static property of the vfio_device
78 * which must be set prior to registering the vfio_device.
79 */
80 struct dentry *debug_root;
81 #endif
82 };
83
84 /**
85 * struct vfio_device_ops - VFIO bus driver device callbacks
86 *
87 * @name: Name of the device driver.
88 * @init: initialize private fields in device structure
89 * @release: Reclaim private fields in device structure
90 * @bind_iommufd: Called when binding the device to an iommufd
91 * @unbind_iommufd: Opposite of bind_iommufd
92 * @attach_ioas: Called when attaching device to an IOAS/HWPT managed by the
93 * bound iommufd. Undo in unbind_iommufd if @detach_ioas is not
94 * called.
95 * @detach_ioas: Opposite of attach_ioas
96 * @pasid_attach_ioas: The pasid variation of attach_ioas
97 * @pasid_detach_ioas: Opposite of pasid_attach_ioas
98 * @open_device: Called when the first file descriptor is opened for this device
99 * @close_device: Opposite of open_device
100 * @read: Perform read(2) on device file descriptor
101 * @write: Perform write(2) on device file descriptor
102 * @ioctl: Perform ioctl(2) on device file descriptor, supporting VFIO_DEVICE_*
103 * operations documented below
104 * @mmap: Perform mmap(2) on a region of the device file descriptor
105 * @request: Request for the bus driver to release the device
106 * @match: Optional device name match callback (return: 0 for no-match, >0 for
107 * match, -errno for abort (ex. match with insufficient or incorrect
108 * additional args)
109 * @match_token_uuid: Optional device token match/validation. Return 0
110 * if the uuid is valid for the device, -errno otherwise. uuid is NULL
111 * if none was provided.
112 * @dma_unmap: Called when userspace unmaps IOVA from the container
113 * this device is attached to.
114 * @device_feature: Optional, fill in the VFIO_DEVICE_FEATURE ioctl
115 */
116 struct vfio_device_ops {
117 char *name;
118 int (*init)(struct vfio_device *vdev);
119 void (*release)(struct vfio_device *vdev);
120 int (*bind_iommufd)(struct vfio_device *vdev,
121 struct iommufd_ctx *ictx, u32 *out_device_id);
122 void (*unbind_iommufd)(struct vfio_device *vdev);
123 int (*attach_ioas)(struct vfio_device *vdev, u32 *pt_id);
124 void (*detach_ioas)(struct vfio_device *vdev);
125 int (*pasid_attach_ioas)(struct vfio_device *vdev, u32 pasid,
126 u32 *pt_id);
127 void (*pasid_detach_ioas)(struct vfio_device *vdev, u32 pasid);
128 int (*open_device)(struct vfio_device *vdev);
129 void (*close_device)(struct vfio_device *vdev);
130 ssize_t (*read)(struct vfio_device *vdev, char __user *buf,
131 size_t count, loff_t *ppos);
132 ssize_t (*write)(struct vfio_device *vdev, const char __user *buf,
133 size_t count, loff_t *size);
134 long (*ioctl)(struct vfio_device *vdev, unsigned int cmd,
135 unsigned long arg);
136 int (*get_region_info_caps)(struct vfio_device *vdev,
137 struct vfio_region_info *info,
138 struct vfio_info_cap *caps);
139 int (*mmap)(struct vfio_device *vdev, struct vm_area_struct *vma);
140 void (*request)(struct vfio_device *vdev, unsigned int count);
141 int (*match)(struct vfio_device *vdev, char *buf);
142 int (*match_token_uuid)(struct vfio_device *vdev, const uuid_t *uuid);
143 void (*dma_unmap)(struct vfio_device *vdev, u64 iova, u64 length);
144 int (*device_feature)(struct vfio_device *device, u32 flags,
145 void __user *arg, size_t argsz);
146 };
147
148 #if IS_ENABLED(CONFIG_IOMMUFD)
149 struct iommufd_ctx *vfio_iommufd_device_ictx(struct vfio_device *vdev);
150 int vfio_iommufd_get_dev_id(struct vfio_device *vdev, struct iommufd_ctx *ictx);
151 int vfio_iommufd_physical_bind(struct vfio_device *vdev,
152 struct iommufd_ctx *ictx, u32 *out_device_id);
153 void vfio_iommufd_physical_unbind(struct vfio_device *vdev);
154 int vfio_iommufd_physical_attach_ioas(struct vfio_device *vdev, u32 *pt_id);
155 void vfio_iommufd_physical_detach_ioas(struct vfio_device *vdev);
156 int vfio_iommufd_physical_pasid_attach_ioas(struct vfio_device *vdev,
157 u32 pasid, u32 *pt_id);
158 void vfio_iommufd_physical_pasid_detach_ioas(struct vfio_device *vdev,
159 u32 pasid);
160 int vfio_iommufd_emulated_bind(struct vfio_device *vdev,
161 struct iommufd_ctx *ictx, u32 *out_device_id);
162 void vfio_iommufd_emulated_unbind(struct vfio_device *vdev);
163 int vfio_iommufd_emulated_attach_ioas(struct vfio_device *vdev, u32 *pt_id);
164 void vfio_iommufd_emulated_detach_ioas(struct vfio_device *vdev);
165 #else
166 static inline struct iommufd_ctx *
vfio_iommufd_device_ictx(struct vfio_device * vdev)167 vfio_iommufd_device_ictx(struct vfio_device *vdev)
168 {
169 return NULL;
170 }
171
172 static inline int
vfio_iommufd_get_dev_id(struct vfio_device * vdev,struct iommufd_ctx * ictx)173 vfio_iommufd_get_dev_id(struct vfio_device *vdev, struct iommufd_ctx *ictx)
174 {
175 return VFIO_PCI_DEVID_NOT_OWNED;
176 }
177
178 #define vfio_iommufd_physical_bind \
179 ((int (*)(struct vfio_device *vdev, struct iommufd_ctx *ictx, \
180 u32 *out_device_id)) NULL)
181 #define vfio_iommufd_physical_unbind \
182 ((void (*)(struct vfio_device *vdev)) NULL)
183 #define vfio_iommufd_physical_attach_ioas \
184 ((int (*)(struct vfio_device *vdev, u32 *pt_id)) NULL)
185 #define vfio_iommufd_physical_detach_ioas \
186 ((void (*)(struct vfio_device *vdev)) NULL)
187 #define vfio_iommufd_physical_pasid_attach_ioas \
188 ((int (*)(struct vfio_device *vdev, u32 pasid, u32 *pt_id)) NULL)
189 #define vfio_iommufd_physical_pasid_detach_ioas \
190 ((void (*)(struct vfio_device *vdev, u32 pasid)) NULL)
191 #define vfio_iommufd_emulated_bind \
192 ((int (*)(struct vfio_device *vdev, struct iommufd_ctx *ictx, \
193 u32 *out_device_id)) NULL)
194 #define vfio_iommufd_emulated_unbind \
195 ((void (*)(struct vfio_device *vdev)) NULL)
196 #define vfio_iommufd_emulated_attach_ioas \
197 ((int (*)(struct vfio_device *vdev, u32 *pt_id)) NULL)
198 #define vfio_iommufd_emulated_detach_ioas \
199 ((void (*)(struct vfio_device *vdev)) NULL)
200 #endif
201
vfio_device_cdev_opened(struct vfio_device * device)202 static inline bool vfio_device_cdev_opened(struct vfio_device *device)
203 {
204 return device->cdev_opened;
205 }
206
207 /**
208 * struct vfio_migration_ops - VFIO bus device driver migration callbacks
209 *
210 * @migration_set_state: Optional callback to change the migration state for
211 * devices that support migration. It's mandatory for
212 * VFIO_DEVICE_FEATURE_MIGRATION migration support.
213 * The returned FD is used for data transfer according to the FSM
214 * definition. The driver is responsible to ensure that FD reaches end
215 * of stream or error whenever the migration FSM leaves a data transfer
216 * state or before close_device() returns.
217 * @migration_get_state: Optional callback to get the migration state for
218 * devices that support migration. It's mandatory for
219 * VFIO_DEVICE_FEATURE_MIGRATION migration support.
220 * @migration_get_data_size: Optional callback to get the estimated data
221 * length that will be required to complete stop copy. It's mandatory for
222 * VFIO_DEVICE_FEATURE_MIGRATION migration support.
223 */
224 struct vfio_migration_ops {
225 struct file *(*migration_set_state)(
226 struct vfio_device *device,
227 enum vfio_device_mig_state new_state);
228 int (*migration_get_state)(struct vfio_device *device,
229 enum vfio_device_mig_state *curr_state);
230 int (*migration_get_data_size)(struct vfio_device *device,
231 unsigned long *stop_copy_length);
232 };
233
234 /**
235 * struct vfio_log_ops - VFIO bus device driver logging callbacks
236 *
237 * @log_start: Optional callback to ask the device start DMA logging.
238 * @log_stop: Optional callback to ask the device stop DMA logging.
239 * @log_read_and_clear: Optional callback to ask the device read
240 * and clear the dirty DMAs in some given range.
241 *
242 * The vfio core implementation of the DEVICE_FEATURE_DMA_LOGGING_ set
243 * of features does not track logging state relative to the device,
244 * therefore the device implementation of vfio_log_ops must handle
245 * arbitrary user requests. This includes rejecting subsequent calls
246 * to log_start without an intervening log_stop, as well as graceful
247 * handling of log_stop and log_read_and_clear from invalid states.
248 */
249 struct vfio_log_ops {
250 int (*log_start)(struct vfio_device *device,
251 struct rb_root_cached *ranges, u32 nnodes, u64 *page_size);
252 int (*log_stop)(struct vfio_device *device);
253 int (*log_read_and_clear)(struct vfio_device *device,
254 unsigned long iova, unsigned long length,
255 struct iova_bitmap *dirty);
256 };
257
258 /**
259 * vfio_check_feature - Validate user input for the VFIO_DEVICE_FEATURE ioctl
260 * @flags: Arg from the device_feature op
261 * @argsz: Arg from the device_feature op
262 * @supported_ops: Combination of VFIO_DEVICE_FEATURE_GET and SET the driver
263 * supports
264 * @minsz: Minimum data size the driver accepts
265 *
266 * For use in a driver's device_feature op. Checks that the inputs to the
267 * VFIO_DEVICE_FEATURE ioctl are correct for the driver's feature. Returns 1 if
268 * the driver should execute the get or set, otherwise the relevant
269 * value should be returned.
270 */
vfio_check_feature(u32 flags,size_t argsz,u32 supported_ops,size_t minsz)271 static inline int vfio_check_feature(u32 flags, size_t argsz, u32 supported_ops,
272 size_t minsz)
273 {
274 if ((flags & (VFIO_DEVICE_FEATURE_GET | VFIO_DEVICE_FEATURE_SET)) &
275 ~supported_ops)
276 return -EINVAL;
277 if (flags & VFIO_DEVICE_FEATURE_PROBE)
278 return 0;
279 /* Without PROBE one of GET or SET must be requested */
280 if (!(flags & (VFIO_DEVICE_FEATURE_GET | VFIO_DEVICE_FEATURE_SET)))
281 return -EINVAL;
282 if (argsz < minsz)
283 return -EINVAL;
284 return 1;
285 }
286
287 struct vfio_device *_vfio_alloc_device(size_t size, struct device *dev,
288 const struct vfio_device_ops *ops);
289 #define vfio_alloc_device(dev_struct, member, dev, ops) \
290 container_of(_vfio_alloc_device(sizeof(struct dev_struct) + \
291 BUILD_BUG_ON_ZERO(offsetof( \
292 struct dev_struct, member)), \
293 dev, ops), \
294 struct dev_struct, member)
295
vfio_put_device(struct vfio_device * device)296 static inline void vfio_put_device(struct vfio_device *device)
297 {
298 put_device(&device->device);
299 }
300
301 int vfio_register_group_dev(struct vfio_device *device);
302 int vfio_register_emulated_iommu_dev(struct vfio_device *device);
303 void vfio_unregister_group_dev(struct vfio_device *device);
304 bool vfio_device_try_get_registration(struct vfio_device *device);
305 void vfio_device_put_registration(struct vfio_device *device);
306
307 int vfio_assign_device_set(struct vfio_device *device, void *set_id);
308 unsigned int vfio_device_set_open_count(struct vfio_device_set *dev_set);
309 struct vfio_device *
310 vfio_find_device_in_devset(struct vfio_device_set *dev_set,
311 struct device *dev);
312
313 int vfio_mig_get_next_state(struct vfio_device *device,
314 enum vfio_device_mig_state cur_fsm,
315 enum vfio_device_mig_state new_fsm,
316 enum vfio_device_mig_state *next_fsm);
317
318 void vfio_combine_iova_ranges(struct rb_root_cached *root, u32 cur_nodes,
319 u32 req_nodes);
320
321 /*
322 * External user API
323 */
324 struct iommu_group *vfio_file_iommu_group(struct file *file);
325
326 #if IS_ENABLED(CONFIG_VFIO_GROUP)
327 bool vfio_file_is_group(struct file *file);
328 bool vfio_file_has_dev(struct file *file, struct vfio_device *device);
329 #else
vfio_file_is_group(struct file * file)330 static inline bool vfio_file_is_group(struct file *file)
331 {
332 return false;
333 }
334
vfio_file_has_dev(struct file * file,struct vfio_device * device)335 static inline bool vfio_file_has_dev(struct file *file, struct vfio_device *device)
336 {
337 return false;
338 }
339 #endif
340 bool vfio_file_is_valid(struct file *file);
341 bool vfio_file_enforced_coherent(struct file *file);
342 void vfio_file_set_kvm(struct file *file, struct kvm *kvm);
343
344 #define VFIO_PIN_PAGES_MAX_ENTRIES (PAGE_SIZE/sizeof(unsigned long))
345
346 int vfio_pin_pages(struct vfio_device *device, dma_addr_t iova,
347 int npage, int prot, struct page **pages);
348 void vfio_unpin_pages(struct vfio_device *device, dma_addr_t iova, int npage);
349 int vfio_dma_rw(struct vfio_device *device, dma_addr_t iova,
350 void *data, size_t len, bool write);
351
352 /*
353 * Sub-module helpers
354 */
355 struct vfio_info_cap {
356 struct vfio_info_cap_header *buf;
357 size_t size;
358 };
359 struct vfio_info_cap_header *vfio_info_cap_add(struct vfio_info_cap *caps,
360 size_t size, u16 id,
361 u16 version);
362 void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset);
363
364 int vfio_info_add_capability(struct vfio_info_cap *caps,
365 struct vfio_info_cap_header *cap, size_t size);
366
367 int vfio_set_irqs_validate_and_prepare(struct vfio_irq_set *hdr,
368 int num_irqs, int max_irq_type,
369 size_t *data_size);
370
371 /*
372 * IRQfd - generic
373 */
374 struct virqfd {
375 void *opaque;
376 struct eventfd_ctx *eventfd;
377 int (*handler)(void *, void *);
378 void (*thread)(void *, void *);
379 void *data;
380 struct work_struct inject;
381 wait_queue_entry_t wait;
382 poll_table pt;
383 struct work_struct shutdown;
384 struct work_struct flush_inject;
385 struct virqfd **pvirqfd;
386 };
387
388 int vfio_virqfd_enable(void *opaque, int (*handler)(void *, void *),
389 void (*thread)(void *, void *), void *data,
390 struct virqfd **pvirqfd, int fd);
391 void vfio_virqfd_disable(struct virqfd **pvirqfd);
392 void vfio_virqfd_flush_thread(struct virqfd **pvirqfd);
393
394 #endif /* VFIO_H */
395