1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_VDPA_H
3#define _LINUX_VDPA_H
4
5#include <linux/kernel.h>
6#include <linux/device.h>
7#include <linux/interrupt.h>
8#include <linux/vhost_iotlb.h>
9#include <linux/virtio_net.h>
10#include <linux/if_ether.h>
11
12/**
13 * struct vdpa_callback - vDPA callback definition.
14 * @callback: interrupt callback function
15 * @private: the data passed to the callback function
16 * @trigger: the eventfd for the callback (Optional).
17 * When it is set, the vDPA driver must guarantee that
18 * signaling it is functional equivalent to triggering
19 * the callback. Then vDPA parent can signal it directly
20 * instead of triggering the callback.
21 */
22struct vdpa_callback {
23 irqreturn_t (*callback)(void *data);
24 void *private;
25 struct eventfd_ctx *trigger;
26};
27
28/**
29 * struct vdpa_notification_area - vDPA notification area
30 * @addr: base address of the notification area
31 * @size: size of the notification area
32 */
33struct vdpa_notification_area {
34 resource_size_t addr;
35 resource_size_t size;
36};
37
38/**
39 * struct vdpa_vq_state_split - vDPA split virtqueue state
40 * @avail_index: available index
41 */
42struct vdpa_vq_state_split {
43 u16 avail_index;
44};
45
46/**
47 * struct vdpa_vq_state_packed - vDPA packed virtqueue state
48 * @last_avail_counter: last driver ring wrap counter observed by device
49 * @last_avail_idx: device available index
50 * @last_used_counter: device ring wrap counter
51 * @last_used_idx: used index
52 */
53struct vdpa_vq_state_packed {
54 u16 last_avail_counter:1;
55 u16 last_avail_idx:15;
56 u16 last_used_counter:1;
57 u16 last_used_idx:15;
58};
59
60struct vdpa_vq_state {
61 union {
62 struct vdpa_vq_state_split split;
63 struct vdpa_vq_state_packed packed;
64 };
65};
66
67struct vdpa_mgmt_dev;
68
69/**
70 * struct vdpa_device - representation of a vDPA device
71 * @dev: underlying device
72 * @dma_dev: the actual device that is performing DMA
73 * @driver_override: driver name to force a match; do not set directly,
74 * because core frees it; use driver_set_override() to
75 * set or clear it.
76 * @config: the configuration ops for this device.
77 * @cf_lock: Protects get and set access to configuration layout.
78 * @index: device index
79 * @features_valid: were features initialized? for legacy guests
80 * @ngroups: the number of virtqueue groups
81 * @nas: the number of address spaces
82 * @use_va: indicate whether virtual address must be used by this device
83 * @nvqs: maximum number of supported virtqueues
84 * @mdev: management device pointer; caller must setup when registering device as part
85 * of dev_add() mgmtdev ops callback before invoking _vdpa_register_device().
86 */
87struct vdpa_device {
88 struct device dev;
89 struct device *dma_dev;
90 const char *driver_override;
91 const struct vdpa_config_ops *config;
92 struct rw_semaphore cf_lock; /* Protects get/set config */
93 unsigned int index;
94 bool features_valid;
95 bool use_va;
96 u32 nvqs;
97 struct vdpa_mgmt_dev *mdev;
98 unsigned int ngroups;
99 unsigned int nas;
100};
101
102/**
103 * struct vdpa_iova_range - the IOVA range support by the device
104 * @first: start of the IOVA range
105 * @last: end of the IOVA range
106 */
107struct vdpa_iova_range {
108 u64 first;
109 u64 last;
110};
111
112struct vdpa_dev_set_config {
113 u64 device_features;
114 struct {
115 u8 mac[ETH_ALEN];
116 u16 mtu;
117 u16 max_vq_pairs;
118 } net;
119 u64 mask;
120};
121
122/**
123 * struct vdpa_map_file - file area for device memory mapping
124 * @file: vma->vm_file for the mapping
125 * @offset: mapping offset in the vm_file
126 */
127struct vdpa_map_file {
128 struct file *file;
129 u64 offset;
130};
131
132/**
133 * struct vdpa_config_ops - operations for configuring a vDPA device.
134 * Note: vDPA device drivers are required to implement all of the
135 * operations unless it is mentioned to be optional in the following
136 * list.
137 *
138 * @set_vq_address: Set the address of virtqueue
139 * @vdev: vdpa device
140 * @idx: virtqueue index
141 * @desc_area: address of desc area
142 * @driver_area: address of driver area
143 * @device_area: address of device area
144 * Returns integer: success (0) or error (< 0)
145 * @set_vq_num: Set the size of virtqueue
146 * @vdev: vdpa device
147 * @idx: virtqueue index
148 * @num: the size of virtqueue
149 * @kick_vq: Kick the virtqueue
150 * @vdev: vdpa device
151 * @idx: virtqueue index
152 * @kick_vq_with_data: Kick the virtqueue and supply extra data
153 * (only if VIRTIO_F_NOTIFICATION_DATA is negotiated)
154 * @vdev: vdpa device
155 * @data for split virtqueue:
156 * 16 bits vqn and 16 bits next available index.
157 * @data for packed virtqueue:
158 * 16 bits vqn, 15 least significant bits of
159 * next available index and 1 bit next_wrap.
160 * @set_vq_cb: Set the interrupt callback function for
161 * a virtqueue
162 * @vdev: vdpa device
163 * @idx: virtqueue index
164 * @cb: virtio-vdev interrupt callback structure
165 * @set_vq_ready: Set ready status for a virtqueue
166 * @vdev: vdpa device
167 * @idx: virtqueue index
168 * @ready: ready (true) not ready(false)
169 * @get_vq_ready: Get ready status for a virtqueue
170 * @vdev: vdpa device
171 * @idx: virtqueue index
172 * Returns boolean: ready (true) or not (false)
173 * @set_vq_state: Set the state for a virtqueue
174 * @vdev: vdpa device
175 * @idx: virtqueue index
176 * @state: pointer to set virtqueue state (last_avail_idx)
177 * Returns integer: success (0) or error (< 0)
178 * @get_vq_state: Get the state for a virtqueue
179 * @vdev: vdpa device
180 * @idx: virtqueue index
181 * @state: pointer to returned state (last_avail_idx)
182 * @get_vendor_vq_stats: Get the vendor statistics of a device.
183 * @vdev: vdpa device
184 * @idx: virtqueue index
185 * @msg: socket buffer holding stats message
186 * @extack: extack for reporting error messages
187 * Returns integer: success (0) or error (< 0)
188 * @get_vq_notification: Get the notification area for a virtqueue (optional)
189 * @vdev: vdpa device
190 * @idx: virtqueue index
191 * Returns the notification area
192 * @get_vq_irq: Get the irq number of a virtqueue (optional,
193 * but must implemented if require vq irq offloading)
194 * @vdev: vdpa device
195 * @idx: virtqueue index
196 * Returns int: irq number of a virtqueue,
197 * negative number if no irq assigned.
198 * @get_vq_align: Get the virtqueue align requirement
199 * for the device
200 * @vdev: vdpa device
201 * Returns virtqueue algin requirement
202 * @get_vq_group: Get the group id for a specific
203 * virtqueue (optional)
204 * @vdev: vdpa device
205 * @idx: virtqueue index
206 * Returns u32: group id for this virtqueue
207 * @get_vq_desc_group: Get the group id for the descriptor table of
208 * a specific virtqueue (optional)
209 * @vdev: vdpa device
210 * @idx: virtqueue index
211 * Returns u32: group id for the descriptor table
212 * portion of this virtqueue. Could be different
213 * than the one from @get_vq_group, in which case
214 * the access to the descriptor table can be
215 * confined to a separate asid, isolating from
216 * the virtqueue's buffer address access.
217 * @get_device_features: Get virtio features supported by the device
218 * @vdev: vdpa device
219 * Returns the virtio features support by the
220 * device
221 * @get_backend_features: Get parent-specific backend features (optional)
222 * Returns the vdpa features supported by the
223 * device.
224 * @set_driver_features: Set virtio features supported by the driver
225 * @vdev: vdpa device
226 * @features: feature support by the driver
227 * Returns integer: success (0) or error (< 0)
228 * @get_driver_features: Get the virtio driver features in action
229 * @vdev: vdpa device
230 * Returns the virtio features accepted
231 * @set_config_cb: Set the config interrupt callback
232 * @vdev: vdpa device
233 * @cb: virtio-vdev interrupt callback structure
234 * @get_vq_num_max: Get the max size of virtqueue
235 * @vdev: vdpa device
236 * Returns u16: max size of virtqueue
237 * @get_vq_num_min: Get the min size of virtqueue (optional)
238 * @vdev: vdpa device
239 * Returns u16: min size of virtqueue
240 * @get_device_id: Get virtio device id
241 * @vdev: vdpa device
242 * Returns u32: virtio device id
243 * @get_vendor_id: Get id for the vendor that provides this device
244 * @vdev: vdpa device
245 * Returns u32: virtio vendor id
246 * @get_status: Get the device status
247 * @vdev: vdpa device
248 * Returns u8: virtio device status
249 * @set_status: Set the device status
250 * @vdev: vdpa device
251 * @status: virtio device status
252 * @reset: Reset device
253 * @vdev: vdpa device
254 * Returns integer: success (0) or error (< 0)
255 * @compat_reset: Reset device with compatibility quirks to
256 * accommodate older userspace. Only needed by
257 * parent driver which used to have bogus reset
258 * behaviour, and has to maintain such behaviour
259 * for compatibility with older userspace.
260 * Historically compliant driver only has to
261 * implement .reset, Historically non-compliant
262 * driver should implement both.
263 * @vdev: vdpa device
264 * @flags: compatibility quirks for reset
265 * Returns integer: success (0) or error (< 0)
266 * @suspend: Suspend the device (optional)
267 * @vdev: vdpa device
268 * Returns integer: success (0) or error (< 0)
269 * @resume: Resume the device (optional)
270 * @vdev: vdpa device
271 * Returns integer: success (0) or error (< 0)
272 * @get_config_size: Get the size of the configuration space includes
273 * fields that are conditional on feature bits.
274 * @vdev: vdpa device
275 * Returns size_t: configuration size
276 * @get_config: Read from device specific configuration space
277 * @vdev: vdpa device
278 * @offset: offset from the beginning of
279 * configuration space
280 * @buf: buffer used to read to
281 * @len: the length to read from
282 * configuration space
283 * @set_config: Write to device specific configuration space
284 * @vdev: vdpa device
285 * @offset: offset from the beginning of
286 * configuration space
287 * @buf: buffer used to write from
288 * @len: the length to write to
289 * configuration space
290 * @get_generation: Get device config generation (optional)
291 * @vdev: vdpa device
292 * Returns u32: device generation
293 * @get_iova_range: Get supported iova range (optional)
294 * @vdev: vdpa device
295 * Returns the iova range supported by
296 * the device.
297 * @set_vq_affinity: Set the affinity of virtqueue (optional)
298 * @vdev: vdpa device
299 * @idx: virtqueue index
300 * @cpu_mask: the affinity mask
301 * Returns integer: success (0) or error (< 0)
302 * @get_vq_affinity: Get the affinity of virtqueue (optional)
303 * @vdev: vdpa device
304 * @idx: virtqueue index
305 * Returns the affinity mask
306 * @set_group_asid: Set address space identifier for a
307 * virtqueue group (optional)
308 * @vdev: vdpa device
309 * @group: virtqueue group
310 * @asid: address space id for this group
311 * Returns integer: success (0) or error (< 0)
312 * @set_map: Set device memory mapping (optional)
313 * Needed for device that using device
314 * specific DMA translation (on-chip IOMMU)
315 * @vdev: vdpa device
316 * @asid: address space identifier
317 * @iotlb: vhost memory mapping to be
318 * used by the vDPA
319 * Returns integer: success (0) or error (< 0)
320 * @dma_map: Map an area of PA to IOVA (optional)
321 * Needed for device that using device
322 * specific DMA translation (on-chip IOMMU)
323 * and preferring incremental map.
324 * @vdev: vdpa device
325 * @asid: address space identifier
326 * @iova: iova to be mapped
327 * @size: size of the area
328 * @pa: physical address for the map
329 * @perm: device access permission (VHOST_MAP_XX)
330 * Returns integer: success (0) or error (< 0)
331 * @dma_unmap: Unmap an area of IOVA (optional but
332 * must be implemented with dma_map)
333 * Needed for device that using device
334 * specific DMA translation (on-chip IOMMU)
335 * and preferring incremental unmap.
336 * @vdev: vdpa device
337 * @asid: address space identifier
338 * @iova: iova to be unmapped
339 * @size: size of the area
340 * Returns integer: success (0) or error (< 0)
341 * @reset_map: Reset device memory mapping to the default
342 * state (optional)
343 * Needed for devices that are using device
344 * specific DMA translation and prefer mapping
345 * to be decoupled from the virtio life cycle,
346 * i.e. device .reset op does not reset mapping
347 * @vdev: vdpa device
348 * @asid: address space identifier
349 * Returns integer: success (0) or error (< 0)
350 * @get_vq_dma_dev: Get the dma device for a specific
351 * virtqueue (optional)
352 * @vdev: vdpa device
353 * @idx: virtqueue index
354 * Returns pointer to structure device or error (NULL)
355 * @bind_mm: Bind the device to a specific address space
356 * so the vDPA framework can use VA when this
357 * callback is implemented. (optional)
358 * @vdev: vdpa device
359 * @mm: address space to bind
360 * @unbind_mm: Unbind the device from the address space
361 * bound using the bind_mm callback. (optional)
362 * @vdev: vdpa device
363 * @free: Free resources that belongs to vDPA (optional)
364 * @vdev: vdpa device
365 */
366struct vdpa_config_ops {
367 /* Virtqueue ops */
368 int (*set_vq_address)(struct vdpa_device *vdev,
369 u16 idx, u64 desc_area, u64 driver_area,
370 u64 device_area);
371 void (*set_vq_num)(struct vdpa_device *vdev, u16 idx, u32 num);
372 void (*kick_vq)(struct vdpa_device *vdev, u16 idx);
373 void (*kick_vq_with_data)(struct vdpa_device *vdev, u32 data);
374 void (*set_vq_cb)(struct vdpa_device *vdev, u16 idx,
375 struct vdpa_callback *cb);
376 void (*set_vq_ready)(struct vdpa_device *vdev, u16 idx, bool ready);
377 bool (*get_vq_ready)(struct vdpa_device *vdev, u16 idx);
378 int (*set_vq_state)(struct vdpa_device *vdev, u16 idx,
379 const struct vdpa_vq_state *state);
380 int (*get_vq_state)(struct vdpa_device *vdev, u16 idx,
381 struct vdpa_vq_state *state);
382 int (*get_vendor_vq_stats)(struct vdpa_device *vdev, u16 idx,
383 struct sk_buff *msg,
384 struct netlink_ext_ack *extack);
385 struct vdpa_notification_area
386 (*get_vq_notification)(struct vdpa_device *vdev, u16 idx);
387 /* vq irq is not expected to be changed once DRIVER_OK is set */
388 int (*get_vq_irq)(struct vdpa_device *vdev, u16 idx);
389
390 /* Device ops */
391 u32 (*get_vq_align)(struct vdpa_device *vdev);
392 u32 (*get_vq_group)(struct vdpa_device *vdev, u16 idx);
393 u32 (*get_vq_desc_group)(struct vdpa_device *vdev, u16 idx);
394 u64 (*get_device_features)(struct vdpa_device *vdev);
395 u64 (*get_backend_features)(const struct vdpa_device *vdev);
396 int (*set_driver_features)(struct vdpa_device *vdev, u64 features);
397 u64 (*get_driver_features)(struct vdpa_device *vdev);
398 void (*set_config_cb)(struct vdpa_device *vdev,
399 struct vdpa_callback *cb);
400 u16 (*get_vq_num_max)(struct vdpa_device *vdev);
401 u16 (*get_vq_num_min)(struct vdpa_device *vdev);
402 u32 (*get_device_id)(struct vdpa_device *vdev);
403 u32 (*get_vendor_id)(struct vdpa_device *vdev);
404 u8 (*get_status)(struct vdpa_device *vdev);
405 void (*set_status)(struct vdpa_device *vdev, u8 status);
406 int (*reset)(struct vdpa_device *vdev);
407 int (*compat_reset)(struct vdpa_device *vdev, u32 flags);
408#define VDPA_RESET_F_CLEAN_MAP 1
409 int (*suspend)(struct vdpa_device *vdev);
410 int (*resume)(struct vdpa_device *vdev);
411 size_t (*get_config_size)(struct vdpa_device *vdev);
412 void (*get_config)(struct vdpa_device *vdev, unsigned int offset,
413 void *buf, unsigned int len);
414 void (*set_config)(struct vdpa_device *vdev, unsigned int offset,
415 const void *buf, unsigned int len);
416 u32 (*get_generation)(struct vdpa_device *vdev);
417 struct vdpa_iova_range (*get_iova_range)(struct vdpa_device *vdev);
418 int (*set_vq_affinity)(struct vdpa_device *vdev, u16 idx,
419 const struct cpumask *cpu_mask);
420 const struct cpumask *(*get_vq_affinity)(struct vdpa_device *vdev,
421 u16 idx);
422
423 /* DMA ops */
424 int (*set_map)(struct vdpa_device *vdev, unsigned int asid,
425 struct vhost_iotlb *iotlb);
426 int (*dma_map)(struct vdpa_device *vdev, unsigned int asid,
427 u64 iova, u64 size, u64 pa, u32 perm, void *opaque);
428 int (*dma_unmap)(struct vdpa_device *vdev, unsigned int asid,
429 u64 iova, u64 size);
430 int (*reset_map)(struct vdpa_device *vdev, unsigned int asid);
431 int (*set_group_asid)(struct vdpa_device *vdev, unsigned int group,
432 unsigned int asid);
433 struct device *(*get_vq_dma_dev)(struct vdpa_device *vdev, u16 idx);
434 int (*bind_mm)(struct vdpa_device *vdev, struct mm_struct *mm);
435 void (*unbind_mm)(struct vdpa_device *vdev);
436
437 /* Free device resources */
438 void (*free)(struct vdpa_device *vdev);
439};
440
441struct vdpa_device *__vdpa_alloc_device(struct device *parent,
442 const struct vdpa_config_ops *config,
443 unsigned int ngroups, unsigned int nas,
444 size_t size, const char *name,
445 bool use_va);
446
447/**
448 * vdpa_alloc_device - allocate and initilaize a vDPA device
449 *
450 * @dev_struct: the type of the parent structure
451 * @member: the name of struct vdpa_device within the @dev_struct
452 * @parent: the parent device
453 * @config: the bus operations that is supported by this device
454 * @ngroups: the number of virtqueue groups supported by this device
455 * @nas: the number of address spaces
456 * @name: name of the vdpa device
457 * @use_va: indicate whether virtual address must be used by this device
458 *
459 * Return allocated data structure or ERR_PTR upon error
460 */
461#define vdpa_alloc_device(dev_struct, member, parent, config, ngroups, nas, \
462 name, use_va) \
463 container_of((__vdpa_alloc_device( \
464 parent, config, ngroups, nas, \
465 (sizeof(dev_struct) + \
466 BUILD_BUG_ON_ZERO(offsetof( \
467 dev_struct, member))), name, use_va)), \
468 dev_struct, member)
469
470int vdpa_register_device(struct vdpa_device *vdev, u32 nvqs);
471void vdpa_unregister_device(struct vdpa_device *vdev);
472
473int _vdpa_register_device(struct vdpa_device *vdev, u32 nvqs);
474void _vdpa_unregister_device(struct vdpa_device *vdev);
475
476/**
477 * struct vdpa_driver - operations for a vDPA driver
478 * @driver: underlying device driver
479 * @probe: the function to call when a device is found. Returns 0 or -errno.
480 * @remove: the function to call when a device is removed.
481 */
482struct vdpa_driver {
483 struct device_driver driver;
484 int (*probe)(struct vdpa_device *vdev);
485 void (*remove)(struct vdpa_device *vdev);
486};
487
488#define vdpa_register_driver(drv) \
489 __vdpa_register_driver(drv, THIS_MODULE)
490int __vdpa_register_driver(struct vdpa_driver *drv, struct module *owner);
491void vdpa_unregister_driver(struct vdpa_driver *drv);
492
493#define module_vdpa_driver(__vdpa_driver) \
494 module_driver(__vdpa_driver, vdpa_register_driver, \
495 vdpa_unregister_driver)
496
497static inline struct vdpa_driver *drv_to_vdpa(struct device_driver *driver)
498{
499 return container_of(driver, struct vdpa_driver, driver);
500}
501
502static inline struct vdpa_device *dev_to_vdpa(struct device *_dev)
503{
504 return container_of(_dev, struct vdpa_device, dev);
505}
506
507static inline void *vdpa_get_drvdata(const struct vdpa_device *vdev)
508{
509 return dev_get_drvdata(dev: &vdev->dev);
510}
511
512static inline void vdpa_set_drvdata(struct vdpa_device *vdev, void *data)
513{
514 dev_set_drvdata(dev: &vdev->dev, data);
515}
516
517static inline struct device *vdpa_get_dma_dev(struct vdpa_device *vdev)
518{
519 return vdev->dma_dev;
520}
521
522static inline int vdpa_reset(struct vdpa_device *vdev, u32 flags)
523{
524 const struct vdpa_config_ops *ops = vdev->config;
525 int ret;
526
527 down_write(sem: &vdev->cf_lock);
528 vdev->features_valid = false;
529 if (ops->compat_reset && flags)
530 ret = ops->compat_reset(vdev, flags);
531 else
532 ret = ops->reset(vdev);
533 up_write(sem: &vdev->cf_lock);
534 return ret;
535}
536
537static inline int vdpa_set_features_unlocked(struct vdpa_device *vdev, u64 features)
538{
539 const struct vdpa_config_ops *ops = vdev->config;
540 int ret;
541
542 vdev->features_valid = true;
543 ret = ops->set_driver_features(vdev, features);
544
545 return ret;
546}
547
548static inline int vdpa_set_features(struct vdpa_device *vdev, u64 features)
549{
550 int ret;
551
552 down_write(sem: &vdev->cf_lock);
553 ret = vdpa_set_features_unlocked(vdev, features);
554 up_write(sem: &vdev->cf_lock);
555
556 return ret;
557}
558
559void vdpa_get_config(struct vdpa_device *vdev, unsigned int offset,
560 void *buf, unsigned int len);
561void vdpa_set_config(struct vdpa_device *dev, unsigned int offset,
562 const void *buf, unsigned int length);
563void vdpa_set_status(struct vdpa_device *vdev, u8 status);
564
565/**
566 * struct vdpa_mgmtdev_ops - vdpa device ops
567 * @dev_add: Add a vdpa device using alloc and register
568 * @mdev: parent device to use for device addition
569 * @name: name of the new vdpa device
570 * @config: config attributes to apply to the device under creation
571 * Driver need to add a new device using _vdpa_register_device()
572 * after fully initializing the vdpa device. Driver must return 0
573 * on success or appropriate error code.
574 * @dev_del: Remove a vdpa device using unregister
575 * @mdev: parent device to use for device removal
576 * @dev: vdpa device to remove
577 * Driver need to remove the specified device by calling
578 * _vdpa_unregister_device().
579 */
580struct vdpa_mgmtdev_ops {
581 int (*dev_add)(struct vdpa_mgmt_dev *mdev, const char *name,
582 const struct vdpa_dev_set_config *config);
583 void (*dev_del)(struct vdpa_mgmt_dev *mdev, struct vdpa_device *dev);
584};
585
586/**
587 * struct vdpa_mgmt_dev - vdpa management device
588 * @device: Management parent device
589 * @ops: operations supported by management device
590 * @id_table: Pointer to device id table of supported ids
591 * @config_attr_mask: bit mask of attributes of type enum vdpa_attr that
592 * management device support during dev_add callback
593 * @list: list entry
594 * @supported_features: features supported by device
595 * @max_supported_vqs: maximum number of virtqueues supported by device
596 */
597struct vdpa_mgmt_dev {
598 struct device *device;
599 const struct vdpa_mgmtdev_ops *ops;
600 struct virtio_device_id *id_table;
601 u64 config_attr_mask;
602 struct list_head list;
603 u64 supported_features;
604 u32 max_supported_vqs;
605};
606
607int vdpa_mgmtdev_register(struct vdpa_mgmt_dev *mdev);
608void vdpa_mgmtdev_unregister(struct vdpa_mgmt_dev *mdev);
609
610#endif /* _LINUX_VDPA_H */
611

source code of linux/include/linux/vdpa.h