xref: /openbmc/linux/include/linux/vdpa.h (revision b63e5c70)
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  */
22 struct 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  */
33 struct 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  */
42 struct 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  */
53 struct 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 
60 struct vdpa_vq_state {
61 	union {
62 		struct vdpa_vq_state_split split;
63 		struct vdpa_vq_state_packed packed;
64 	};
65 };
66 
67 struct 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  */
87 struct 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  */
107 struct vdpa_iova_range {
108 	u64 first;
109 	u64 last;
110 };
111 
112 struct 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  */
127 struct 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_device_features:	Get virtio features supported by the device
208  *				@vdev: vdpa device
209  *				Returns the virtio features support by the
210  *				device
211  * @get_backend_features:	Get parent-specific backend features (optional)
212  *				Returns the vdpa features supported by the
213  *				device.
214  * @set_driver_features:	Set virtio features supported by the driver
215  *				@vdev: vdpa device
216  *				@features: feature support by the driver
217  *				Returns integer: success (0) or error (< 0)
218  * @get_driver_features:	Get the virtio driver features in action
219  *				@vdev: vdpa device
220  *				Returns the virtio features accepted
221  * @set_config_cb:		Set the config interrupt callback
222  *				@vdev: vdpa device
223  *				@cb: virtio-vdev interrupt callback structure
224  * @get_vq_num_max:		Get the max size of virtqueue
225  *				@vdev: vdpa device
226  *				Returns u16: max size of virtqueue
227  * @get_vq_num_min:		Get the min size of virtqueue (optional)
228  *				@vdev: vdpa device
229  *				Returns u16: min size of virtqueue
230  * @get_device_id:		Get virtio device id
231  *				@vdev: vdpa device
232  *				Returns u32: virtio device id
233  * @get_vendor_id:		Get id for the vendor that provides this device
234  *				@vdev: vdpa device
235  *				Returns u32: virtio vendor id
236  * @get_status:			Get the device status
237  *				@vdev: vdpa device
238  *				Returns u8: virtio device status
239  * @set_status:			Set the device status
240  *				@vdev: vdpa device
241  *				@status: virtio device status
242  * @reset:			Reset device
243  *				@vdev: vdpa device
244  *				Returns integer: success (0) or error (< 0)
245  * @suspend:			Suspend the device (optional)
246  *				@vdev: vdpa device
247  *				Returns integer: success (0) or error (< 0)
248  * @resume:			Resume the device (optional)
249  *				@vdev: vdpa device
250  *				Returns integer: success (0) or error (< 0)
251  * @get_config_size:		Get the size of the configuration space includes
252  *				fields that are conditional on feature bits.
253  *				@vdev: vdpa device
254  *				Returns size_t: configuration size
255  * @get_config:			Read from device specific configuration space
256  *				@vdev: vdpa device
257  *				@offset: offset from the beginning of
258  *				configuration space
259  *				@buf: buffer used to read to
260  *				@len: the length to read from
261  *				configuration space
262  * @set_config:			Write to device specific configuration space
263  *				@vdev: vdpa device
264  *				@offset: offset from the beginning of
265  *				configuration space
266  *				@buf: buffer used to write from
267  *				@len: the length to write to
268  *				configuration space
269  * @get_generation:		Get device config generation (optional)
270  *				@vdev: vdpa device
271  *				Returns u32: device generation
272  * @get_iova_range:		Get supported iova range (optional)
273  *				@vdev: vdpa device
274  *				Returns the iova range supported by
275  *				the device.
276  * @set_vq_affinity:		Set the affinity of virtqueue (optional)
277  *				@vdev: vdpa device
278  *				@idx: virtqueue index
279  *				@cpu_mask: the affinity mask
280  *				Returns integer: success (0) or error (< 0)
281  * @get_vq_affinity:		Get the affinity of virtqueue (optional)
282  *				@vdev: vdpa device
283  *				@idx: virtqueue index
284  *				Returns the affinity mask
285  * @set_group_asid:		Set address space identifier for a
286  *				virtqueue group (optional)
287  *				@vdev: vdpa device
288  *				@group: virtqueue group
289  *				@asid: address space id for this group
290  *				Returns integer: success (0) or error (< 0)
291  * @set_map:			Set device memory mapping (optional)
292  *				Needed for device that using device
293  *				specific DMA translation (on-chip IOMMU)
294  *				@vdev: vdpa device
295  *				@asid: address space identifier
296  *				@iotlb: vhost memory mapping to be
297  *				used by the vDPA
298  *				Returns integer: success (0) or error (< 0)
299  * @dma_map:			Map an area of PA to IOVA (optional)
300  *				Needed for device that using device
301  *				specific DMA translation (on-chip IOMMU)
302  *				and preferring incremental map.
303  *				@vdev: vdpa device
304  *				@asid: address space identifier
305  *				@iova: iova to be mapped
306  *				@size: size of the area
307  *				@pa: physical address for the map
308  *				@perm: device access permission (VHOST_MAP_XX)
309  *				Returns integer: success (0) or error (< 0)
310  * @dma_unmap:			Unmap an area of IOVA (optional but
311  *				must be implemented with dma_map)
312  *				Needed for device that using device
313  *				specific DMA translation (on-chip IOMMU)
314  *				and preferring incremental unmap.
315  *				@vdev: vdpa device
316  *				@asid: address space identifier
317  *				@iova: iova to be unmapped
318  *				@size: size of the area
319  *				Returns integer: success (0) or error (< 0)
320  * @get_vq_dma_dev:		Get the dma device for a specific
321  *				virtqueue (optional)
322  *				@vdev: vdpa device
323  *				@idx: virtqueue index
324  *				Returns pointer to structure device or error (NULL)
325  * @bind_mm:			Bind the device to a specific address space
326  *				so the vDPA framework can use VA when this
327  *				callback is implemented. (optional)
328  *				@vdev: vdpa device
329  *				@mm: address space to bind
330  * @unbind_mm:			Unbind the device from the address space
331  *				bound using the bind_mm callback. (optional)
332  *				@vdev: vdpa device
333  * @free:			Free resources that belongs to vDPA (optional)
334  *				@vdev: vdpa device
335  */
336 struct vdpa_config_ops {
337 	/* Virtqueue ops */
338 	int (*set_vq_address)(struct vdpa_device *vdev,
339 			      u16 idx, u64 desc_area, u64 driver_area,
340 			      u64 device_area);
341 	void (*set_vq_num)(struct vdpa_device *vdev, u16 idx, u32 num);
342 	void (*kick_vq)(struct vdpa_device *vdev, u16 idx);
343 	void (*kick_vq_with_data)(struct vdpa_device *vdev, u32 data);
344 	void (*set_vq_cb)(struct vdpa_device *vdev, u16 idx,
345 			  struct vdpa_callback *cb);
346 	void (*set_vq_ready)(struct vdpa_device *vdev, u16 idx, bool ready);
347 	bool (*get_vq_ready)(struct vdpa_device *vdev, u16 idx);
348 	int (*set_vq_state)(struct vdpa_device *vdev, u16 idx,
349 			    const struct vdpa_vq_state *state);
350 	int (*get_vq_state)(struct vdpa_device *vdev, u16 idx,
351 			    struct vdpa_vq_state *state);
352 	int (*get_vendor_vq_stats)(struct vdpa_device *vdev, u16 idx,
353 				   struct sk_buff *msg,
354 				   struct netlink_ext_ack *extack);
355 	struct vdpa_notification_area
356 	(*get_vq_notification)(struct vdpa_device *vdev, u16 idx);
357 	/* vq irq is not expected to be changed once DRIVER_OK is set */
358 	int (*get_vq_irq)(struct vdpa_device *vdev, u16 idx);
359 
360 	/* Device ops */
361 	u32 (*get_vq_align)(struct vdpa_device *vdev);
362 	u32 (*get_vq_group)(struct vdpa_device *vdev, u16 idx);
363 	u64 (*get_device_features)(struct vdpa_device *vdev);
364 	u64 (*get_backend_features)(const struct vdpa_device *vdev);
365 	int (*set_driver_features)(struct vdpa_device *vdev, u64 features);
366 	u64 (*get_driver_features)(struct vdpa_device *vdev);
367 	void (*set_config_cb)(struct vdpa_device *vdev,
368 			      struct vdpa_callback *cb);
369 	u16 (*get_vq_num_max)(struct vdpa_device *vdev);
370 	u16 (*get_vq_num_min)(struct vdpa_device *vdev);
371 	u32 (*get_device_id)(struct vdpa_device *vdev);
372 	u32 (*get_vendor_id)(struct vdpa_device *vdev);
373 	u8 (*get_status)(struct vdpa_device *vdev);
374 	void (*set_status)(struct vdpa_device *vdev, u8 status);
375 	int (*reset)(struct vdpa_device *vdev);
376 	int (*suspend)(struct vdpa_device *vdev);
377 	int (*resume)(struct vdpa_device *vdev);
378 	size_t (*get_config_size)(struct vdpa_device *vdev);
379 	void (*get_config)(struct vdpa_device *vdev, unsigned int offset,
380 			   void *buf, unsigned int len);
381 	void (*set_config)(struct vdpa_device *vdev, unsigned int offset,
382 			   const void *buf, unsigned int len);
383 	u32 (*get_generation)(struct vdpa_device *vdev);
384 	struct vdpa_iova_range (*get_iova_range)(struct vdpa_device *vdev);
385 	int (*set_vq_affinity)(struct vdpa_device *vdev, u16 idx,
386 			       const struct cpumask *cpu_mask);
387 	const struct cpumask *(*get_vq_affinity)(struct vdpa_device *vdev,
388 						 u16 idx);
389 
390 	/* DMA ops */
391 	int (*set_map)(struct vdpa_device *vdev, unsigned int asid,
392 		       struct vhost_iotlb *iotlb);
393 	int (*dma_map)(struct vdpa_device *vdev, unsigned int asid,
394 		       u64 iova, u64 size, u64 pa, u32 perm, void *opaque);
395 	int (*dma_unmap)(struct vdpa_device *vdev, unsigned int asid,
396 			 u64 iova, u64 size);
397 	int (*set_group_asid)(struct vdpa_device *vdev, unsigned int group,
398 			      unsigned int asid);
399 	struct device *(*get_vq_dma_dev)(struct vdpa_device *vdev, u16 idx);
400 	int (*bind_mm)(struct vdpa_device *vdev, struct mm_struct *mm);
401 	void (*unbind_mm)(struct vdpa_device *vdev);
402 
403 	/* Free device resources */
404 	void (*free)(struct vdpa_device *vdev);
405 };
406 
407 struct vdpa_device *__vdpa_alloc_device(struct device *parent,
408 					const struct vdpa_config_ops *config,
409 					unsigned int ngroups, unsigned int nas,
410 					size_t size, const char *name,
411 					bool use_va);
412 
413 /**
414  * vdpa_alloc_device - allocate and initilaize a vDPA device
415  *
416  * @dev_struct: the type of the parent structure
417  * @member: the name of struct vdpa_device within the @dev_struct
418  * @parent: the parent device
419  * @config: the bus operations that is supported by this device
420  * @ngroups: the number of virtqueue groups supported by this device
421  * @nas: the number of address spaces
422  * @name: name of the vdpa device
423  * @use_va: indicate whether virtual address must be used by this device
424  *
425  * Return allocated data structure or ERR_PTR upon error
426  */
427 #define vdpa_alloc_device(dev_struct, member, parent, config, ngroups, nas, \
428 			  name, use_va) \
429 			  container_of((__vdpa_alloc_device( \
430 				       parent, config, ngroups, nas, \
431 				       (sizeof(dev_struct) + \
432 				       BUILD_BUG_ON_ZERO(offsetof( \
433 				       dev_struct, member))), name, use_va)), \
434 				       dev_struct, member)
435 
436 int vdpa_register_device(struct vdpa_device *vdev, u32 nvqs);
437 void vdpa_unregister_device(struct vdpa_device *vdev);
438 
439 int _vdpa_register_device(struct vdpa_device *vdev, u32 nvqs);
440 void _vdpa_unregister_device(struct vdpa_device *vdev);
441 
442 /**
443  * struct vdpa_driver - operations for a vDPA driver
444  * @driver: underlying device driver
445  * @probe: the function to call when a device is found.  Returns 0 or -errno.
446  * @remove: the function to call when a device is removed.
447  */
448 struct vdpa_driver {
449 	struct device_driver driver;
450 	int (*probe)(struct vdpa_device *vdev);
451 	void (*remove)(struct vdpa_device *vdev);
452 };
453 
454 #define vdpa_register_driver(drv) \
455 	__vdpa_register_driver(drv, THIS_MODULE)
456 int __vdpa_register_driver(struct vdpa_driver *drv, struct module *owner);
457 void vdpa_unregister_driver(struct vdpa_driver *drv);
458 
459 #define module_vdpa_driver(__vdpa_driver) \
460 	module_driver(__vdpa_driver, vdpa_register_driver,	\
461 		      vdpa_unregister_driver)
462 
drv_to_vdpa(struct device_driver * driver)463 static inline struct vdpa_driver *drv_to_vdpa(struct device_driver *driver)
464 {
465 	return container_of(driver, struct vdpa_driver, driver);
466 }
467 
dev_to_vdpa(struct device * _dev)468 static inline struct vdpa_device *dev_to_vdpa(struct device *_dev)
469 {
470 	return container_of(_dev, struct vdpa_device, dev);
471 }
472 
vdpa_get_drvdata(const struct vdpa_device * vdev)473 static inline void *vdpa_get_drvdata(const struct vdpa_device *vdev)
474 {
475 	return dev_get_drvdata(&vdev->dev);
476 }
477 
vdpa_set_drvdata(struct vdpa_device * vdev,void * data)478 static inline void vdpa_set_drvdata(struct vdpa_device *vdev, void *data)
479 {
480 	dev_set_drvdata(&vdev->dev, data);
481 }
482 
vdpa_get_dma_dev(struct vdpa_device * vdev)483 static inline struct device *vdpa_get_dma_dev(struct vdpa_device *vdev)
484 {
485 	return vdev->dma_dev;
486 }
487 
vdpa_reset(struct vdpa_device * vdev)488 static inline int vdpa_reset(struct vdpa_device *vdev)
489 {
490 	const struct vdpa_config_ops *ops = vdev->config;
491 	int ret;
492 
493 	down_write(&vdev->cf_lock);
494 	vdev->features_valid = false;
495 	ret = ops->reset(vdev);
496 	up_write(&vdev->cf_lock);
497 	return ret;
498 }
499 
vdpa_set_features_unlocked(struct vdpa_device * vdev,u64 features)500 static inline int vdpa_set_features_unlocked(struct vdpa_device *vdev, u64 features)
501 {
502 	const struct vdpa_config_ops *ops = vdev->config;
503 	int ret;
504 
505 	vdev->features_valid = true;
506 	ret = ops->set_driver_features(vdev, features);
507 
508 	return ret;
509 }
510 
vdpa_set_features(struct vdpa_device * vdev,u64 features)511 static inline int vdpa_set_features(struct vdpa_device *vdev, u64 features)
512 {
513 	int ret;
514 
515 	down_write(&vdev->cf_lock);
516 	ret = vdpa_set_features_unlocked(vdev, features);
517 	up_write(&vdev->cf_lock);
518 
519 	return ret;
520 }
521 
522 void vdpa_get_config(struct vdpa_device *vdev, unsigned int offset,
523 		     void *buf, unsigned int len);
524 void vdpa_set_config(struct vdpa_device *dev, unsigned int offset,
525 		     const void *buf, unsigned int length);
526 void vdpa_set_status(struct vdpa_device *vdev, u8 status);
527 
528 /**
529  * struct vdpa_mgmtdev_ops - vdpa device ops
530  * @dev_add: Add a vdpa device using alloc and register
531  *	     @mdev: parent device to use for device addition
532  *	     @name: name of the new vdpa device
533  *	     @config: config attributes to apply to the device under creation
534  *	     Driver need to add a new device using _vdpa_register_device()
535  *	     after fully initializing the vdpa device. Driver must return 0
536  *	     on success or appropriate error code.
537  * @dev_del: Remove a vdpa device using unregister
538  *	     @mdev: parent device to use for device removal
539  *	     @dev: vdpa device to remove
540  *	     Driver need to remove the specified device by calling
541  *	     _vdpa_unregister_device().
542  */
543 struct vdpa_mgmtdev_ops {
544 	int (*dev_add)(struct vdpa_mgmt_dev *mdev, const char *name,
545 		       const struct vdpa_dev_set_config *config);
546 	void (*dev_del)(struct vdpa_mgmt_dev *mdev, struct vdpa_device *dev);
547 };
548 
549 /**
550  * struct vdpa_mgmt_dev - vdpa management device
551  * @device: Management parent device
552  * @ops: operations supported by management device
553  * @id_table: Pointer to device id table of supported ids
554  * @config_attr_mask: bit mask of attributes of type enum vdpa_attr that
555  *		      management device support during dev_add callback
556  * @list: list entry
557  * @supported_features: features supported by device
558  * @max_supported_vqs: maximum number of virtqueues supported by device
559  */
560 struct vdpa_mgmt_dev {
561 	struct device *device;
562 	const struct vdpa_mgmtdev_ops *ops;
563 	struct virtio_device_id *id_table;
564 	u64 config_attr_mask;
565 	struct list_head list;
566 	u64 supported_features;
567 	u32 max_supported_vqs;
568 };
569 
570 int vdpa_mgmtdev_register(struct vdpa_mgmt_dev *mdev);
571 void vdpa_mgmtdev_unregister(struct vdpa_mgmt_dev *mdev);
572 
573 #endif /* _LINUX_VDPA_H */
574