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