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