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 * @dma_unmap: Called when userspace unmaps IOVA from the container
109 * this device is attached to.
110 * @device_feature: Optional, fill in the VFIO_DEVICE_FEATURE ioctl
111 */
112 struct vfio_device_ops {
113 char *name;
114 int (*init)(struct vfio_device *vdev);
115 void (*release)(struct vfio_device *vdev);
116 int (*bind_iommufd)(struct vfio_device *vdev,
117 struct iommufd_ctx *ictx, u32 *out_device_id);
118 void (*unbind_iommufd)(struct vfio_device *vdev);
119 int (*attach_ioas)(struct vfio_device *vdev, u32 *pt_id);
120 void (*detach_ioas)(struct vfio_device *vdev);
121 int (*pasid_attach_ioas)(struct vfio_device *vdev, u32 pasid,
122 u32 *pt_id);
123 void (*pasid_detach_ioas)(struct vfio_device *vdev, u32 pasid);
124 int (*open_device)(struct vfio_device *vdev);
125 void (*close_device)(struct vfio_device *vdev);
126 ssize_t (*read)(struct vfio_device *vdev, char __user *buf,
127 size_t count, loff_t *ppos);
128 ssize_t (*write)(struct vfio_device *vdev, const char __user *buf,
129 size_t count, loff_t *size);
130 long (*ioctl)(struct vfio_device *vdev, unsigned int cmd,
131 unsigned long arg);
132 int (*mmap)(struct vfio_device *vdev, struct vm_area_struct *vma);
133 void (*request)(struct vfio_device *vdev, unsigned int count);
134 int (*match)(struct vfio_device *vdev, char *buf);
135 void (*dma_unmap)(struct vfio_device *vdev, u64 iova, u64 length);
136 int (*device_feature)(struct vfio_device *device, u32 flags,
137 void __user *arg, size_t argsz);
138 };
139
140 #if IS_ENABLED(CONFIG_IOMMUFD)
141 struct iommufd_ctx *vfio_iommufd_device_ictx(struct vfio_device *vdev);
142 int vfio_iommufd_get_dev_id(struct vfio_device *vdev, struct iommufd_ctx *ictx);
143 int vfio_iommufd_physical_bind(struct vfio_device *vdev,
144 struct iommufd_ctx *ictx, u32 *out_device_id);
145 void vfio_iommufd_physical_unbind(struct vfio_device *vdev);
146 int vfio_iommufd_physical_attach_ioas(struct vfio_device *vdev, u32 *pt_id);
147 void vfio_iommufd_physical_detach_ioas(struct vfio_device *vdev);
148 int vfio_iommufd_physical_pasid_attach_ioas(struct vfio_device *vdev,
149 u32 pasid, u32 *pt_id);
150 void vfio_iommufd_physical_pasid_detach_ioas(struct vfio_device *vdev,
151 u32 pasid);
152 int vfio_iommufd_emulated_bind(struct vfio_device *vdev,
153 struct iommufd_ctx *ictx, u32 *out_device_id);
154 void vfio_iommufd_emulated_unbind(struct vfio_device *vdev);
155 int vfio_iommufd_emulated_attach_ioas(struct vfio_device *vdev, u32 *pt_id);
156 void vfio_iommufd_emulated_detach_ioas(struct vfio_device *vdev);
157 #else
158 static inline struct iommufd_ctx *
vfio_iommufd_device_ictx(struct vfio_device * vdev)159 vfio_iommufd_device_ictx(struct vfio_device *vdev)
160 {
161 return NULL;
162 }
163
164 static inline int
vfio_iommufd_get_dev_id(struct vfio_device * vdev,struct iommufd_ctx * ictx)165 vfio_iommufd_get_dev_id(struct vfio_device *vdev, struct iommufd_ctx *ictx)
166 {
167 return VFIO_PCI_DEVID_NOT_OWNED;
168 }
169
170 #define vfio_iommufd_physical_bind \
171 ((int (*)(struct vfio_device *vdev, struct iommufd_ctx *ictx, \
172 u32 *out_device_id)) NULL)
173 #define vfio_iommufd_physical_unbind \
174 ((void (*)(struct vfio_device *vdev)) NULL)
175 #define vfio_iommufd_physical_attach_ioas \
176 ((int (*)(struct vfio_device *vdev, u32 *pt_id)) NULL)
177 #define vfio_iommufd_physical_detach_ioas \
178 ((void (*)(struct vfio_device *vdev)) NULL)
179 #define vfio_iommufd_physical_pasid_attach_ioas \
180 ((int (*)(struct vfio_device *vdev, u32 pasid, u32 *pt_id)) NULL)
181 #define vfio_iommufd_physical_pasid_detach_ioas \
182 ((void (*)(struct vfio_device *vdev, u32 pasid)) NULL)
183 #define vfio_iommufd_emulated_bind \
184 ((int (*)(struct vfio_device *vdev, struct iommufd_ctx *ictx, \
185 u32 *out_device_id)) NULL)
186 #define vfio_iommufd_emulated_unbind \
187 ((void (*)(struct vfio_device *vdev)) NULL)
188 #define vfio_iommufd_emulated_attach_ioas \
189 ((int (*)(struct vfio_device *vdev, u32 *pt_id)) NULL)
190 #define vfio_iommufd_emulated_detach_ioas \
191 ((void (*)(struct vfio_device *vdev)) NULL)
192 #endif
193
vfio_device_cdev_opened(struct vfio_device * device)194 static inline bool vfio_device_cdev_opened(struct vfio_device *device)
195 {
196 return device->cdev_opened;
197 }
198
199 /**
200 * struct vfio_migration_ops - VFIO bus device driver migration callbacks
201 *
202 * @migration_set_state: Optional callback to change the migration state for
203 * devices that support migration. It's mandatory for
204 * VFIO_DEVICE_FEATURE_MIGRATION migration support.
205 * The returned FD is used for data transfer according to the FSM
206 * definition. The driver is responsible to ensure that FD reaches end
207 * of stream or error whenever the migration FSM leaves a data transfer
208 * state or before close_device() returns.
209 * @migration_get_state: Optional callback to get the migration state for
210 * devices that support migration. It's mandatory for
211 * VFIO_DEVICE_FEATURE_MIGRATION migration support.
212 * @migration_get_data_size: Optional callback to get the estimated data
213 * length that will be required to complete stop copy. It's mandatory for
214 * VFIO_DEVICE_FEATURE_MIGRATION migration support.
215 */
216 struct vfio_migration_ops {
217 struct file *(*migration_set_state)(
218 struct vfio_device *device,
219 enum vfio_device_mig_state new_state);
220 int (*migration_get_state)(struct vfio_device *device,
221 enum vfio_device_mig_state *curr_state);
222 int (*migration_get_data_size)(struct vfio_device *device,
223 unsigned long *stop_copy_length);
224 };
225
226 /**
227 * struct vfio_log_ops - VFIO bus device driver logging callbacks
228 *
229 * @log_start: Optional callback to ask the device start DMA logging.
230 * @log_stop: Optional callback to ask the device stop DMA logging.
231 * @log_read_and_clear: Optional callback to ask the device read
232 * and clear the dirty DMAs in some given range.
233 *
234 * The vfio core implementation of the DEVICE_FEATURE_DMA_LOGGING_ set
235 * of features does not track logging state relative to the device,
236 * therefore the device implementation of vfio_log_ops must handle
237 * arbitrary user requests. This includes rejecting subsequent calls
238 * to log_start without an intervening log_stop, as well as graceful
239 * handling of log_stop and log_read_and_clear from invalid states.
240 */
241 struct vfio_log_ops {
242 int (*log_start)(struct vfio_device *device,
243 struct rb_root_cached *ranges, u32 nnodes, u64 *page_size);
244 int (*log_stop)(struct vfio_device *device);
245 int (*log_read_and_clear)(struct vfio_device *device,
246 unsigned long iova, unsigned long length,
247 struct iova_bitmap *dirty);
248 };
249
250 /**
251 * vfio_check_feature - Validate user input for the VFIO_DEVICE_FEATURE ioctl
252 * @flags: Arg from the device_feature op
253 * @argsz: Arg from the device_feature op
254 * @supported_ops: Combination of VFIO_DEVICE_FEATURE_GET and SET the driver
255 * supports
256 * @minsz: Minimum data size the driver accepts
257 *
258 * For use in a driver's device_feature op. Checks that the inputs to the
259 * VFIO_DEVICE_FEATURE ioctl are correct for the driver's feature. Returns 1 if
260 * the driver should execute the get or set, otherwise the relevant
261 * value should be returned.
262 */
vfio_check_feature(u32 flags,size_t argsz,u32 supported_ops,size_t minsz)263 static inline int vfio_check_feature(u32 flags, size_t argsz, u32 supported_ops,
264 size_t minsz)
265 {
266 if ((flags & (VFIO_DEVICE_FEATURE_GET | VFIO_DEVICE_FEATURE_SET)) &
267 ~supported_ops)
268 return -EINVAL;
269 if (flags & VFIO_DEVICE_FEATURE_PROBE)
270 return 0;
271 /* Without PROBE one of GET or SET must be requested */
272 if (!(flags & (VFIO_DEVICE_FEATURE_GET | VFIO_DEVICE_FEATURE_SET)))
273 return -EINVAL;
274 if (argsz < minsz)
275 return -EINVAL;
276 return 1;
277 }
278
279 struct vfio_device *_vfio_alloc_device(size_t size, struct device *dev,
280 const struct vfio_device_ops *ops);
281 #define vfio_alloc_device(dev_struct, member, dev, ops) \
282 container_of(_vfio_alloc_device(sizeof(struct dev_struct) + \
283 BUILD_BUG_ON_ZERO(offsetof( \
284 struct dev_struct, member)), \
285 dev, ops), \
286 struct dev_struct, member)
287
vfio_put_device(struct vfio_device * device)288 static inline void vfio_put_device(struct vfio_device *device)
289 {
290 put_device(&device->device);
291 }
292
293 int vfio_register_group_dev(struct vfio_device *device);
294 int vfio_register_emulated_iommu_dev(struct vfio_device *device);
295 void vfio_unregister_group_dev(struct vfio_device *device);
296
297 int vfio_assign_device_set(struct vfio_device *device, void *set_id);
298 unsigned int vfio_device_set_open_count(struct vfio_device_set *dev_set);
299 struct vfio_device *
300 vfio_find_device_in_devset(struct vfio_device_set *dev_set,
301 struct device *dev);
302
303 int vfio_mig_get_next_state(struct vfio_device *device,
304 enum vfio_device_mig_state cur_fsm,
305 enum vfio_device_mig_state new_fsm,
306 enum vfio_device_mig_state *next_fsm);
307
308 void vfio_combine_iova_ranges(struct rb_root_cached *root, u32 cur_nodes,
309 u32 req_nodes);
310
311 /*
312 * External user API
313 */
314 struct iommu_group *vfio_file_iommu_group(struct file *file);
315
316 #if IS_ENABLED(CONFIG_VFIO_GROUP)
317 bool vfio_file_is_group(struct file *file);
318 bool vfio_file_has_dev(struct file *file, struct vfio_device *device);
319 #else
vfio_file_is_group(struct file * file)320 static inline bool vfio_file_is_group(struct file *file)
321 {
322 return false;
323 }
324
vfio_file_has_dev(struct file * file,struct vfio_device * device)325 static inline bool vfio_file_has_dev(struct file *file, struct vfio_device *device)
326 {
327 return false;
328 }
329 #endif
330 bool vfio_file_is_valid(struct file *file);
331 bool vfio_file_enforced_coherent(struct file *file);
332 void vfio_file_set_kvm(struct file *file, struct kvm *kvm);
333
334 #define VFIO_PIN_PAGES_MAX_ENTRIES (PAGE_SIZE/sizeof(unsigned long))
335
336 int vfio_pin_pages(struct vfio_device *device, dma_addr_t iova,
337 int npage, int prot, struct page **pages);
338 void vfio_unpin_pages(struct vfio_device *device, dma_addr_t iova, int npage);
339 int vfio_dma_rw(struct vfio_device *device, dma_addr_t iova,
340 void *data, size_t len, bool write);
341
342 /*
343 * Sub-module helpers
344 */
345 struct vfio_info_cap {
346 struct vfio_info_cap_header *buf;
347 size_t size;
348 };
349 struct vfio_info_cap_header *vfio_info_cap_add(struct vfio_info_cap *caps,
350 size_t size, u16 id,
351 u16 version);
352 void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset);
353
354 int vfio_info_add_capability(struct vfio_info_cap *caps,
355 struct vfio_info_cap_header *cap, size_t size);
356
357 int vfio_set_irqs_validate_and_prepare(struct vfio_irq_set *hdr,
358 int num_irqs, int max_irq_type,
359 size_t *data_size);
360
361 /*
362 * IRQfd - generic
363 */
364 struct virqfd {
365 void *opaque;
366 struct eventfd_ctx *eventfd;
367 int (*handler)(void *, void *);
368 void (*thread)(void *, void *);
369 void *data;
370 struct work_struct inject;
371 wait_queue_entry_t wait;
372 poll_table pt;
373 struct work_struct shutdown;
374 struct work_struct flush_inject;
375 struct virqfd **pvirqfd;
376 };
377
378 int vfio_virqfd_enable(void *opaque, int (*handler)(void *, void *),
379 void (*thread)(void *, void *), void *data,
380 struct virqfd **pvirqfd, int fd);
381 void vfio_virqfd_disable(struct virqfd **pvirqfd);
382 void vfio_virqfd_flush_thread(struct virqfd **pvirqfd);
383
384 #endif /* VFIO_H */
385