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