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_calllback - vDPA callback definition.
14  * @callback: interrupt callback function
15  * @private: the data passed to the callback function
16  */
17 struct vdpa_callback {
18 	irqreturn_t (*callback)(void *data);
19 	void *private;
20 };
21 
22 /**
23  * struct vdpa_notification_area - vDPA notification area
24  * @addr: base address of the notification area
25  * @size: size of the notification area
26  */
27 struct vdpa_notification_area {
28 	resource_size_t addr;
29 	resource_size_t size;
30 };
31 
32 /**
33  * struct vdpa_vq_state_split - vDPA split virtqueue state
34  * @avail_index: available index
35  */
36 struct vdpa_vq_state_split {
37 	u16	avail_index;
38 };
39 
40 /**
41  * struct vdpa_vq_state_packed - vDPA packed virtqueue state
42  * @last_avail_counter: last driver ring wrap counter observed by device
43  * @last_avail_idx: device available index
44  * @last_used_counter: device ring wrap counter
45  * @last_used_idx: used index
46  */
47 struct vdpa_vq_state_packed {
48 	u16	last_avail_counter:1;
49 	u16	last_avail_idx:15;
50 	u16	last_used_counter:1;
51 	u16	last_used_idx:15;
52 };
53 
54 struct vdpa_vq_state {
55 	union {
56 		struct vdpa_vq_state_split split;
57 		struct vdpa_vq_state_packed packed;
58 	};
59 };
60 
61 struct vdpa_mgmt_dev;
62 
63 /**
64  * struct vdpa_device - representation of a vDPA device
65  * @dev: underlying device
66  * @dma_dev: the actual device that is performing DMA
67  * @driver_override: driver name to force a match; do not set directly,
68  *                   because core frees it; use driver_set_override() to
69  *                   set or clear it.
70  * @config: the configuration ops for this device.
71  * @cf_lock: Protects get and set access to configuration layout.
72  * @index: device index
73  * @features_valid: were features initialized? for legacy guests
74  * @ngroups: the number of virtqueue groups
75  * @nas: the number of address spaces
76  * @use_va: indicate whether virtual address must be used by this device
77  * @nvqs: maximum number of supported virtqueues
78  * @mdev: management device pointer; caller must setup when registering device as part
79  *	  of dev_add() mgmtdev ops callback before invoking _vdpa_register_device().
80  */
81 struct vdpa_device {
82 	struct device dev;
83 	struct device *dma_dev;
84 	const char *driver_override;
85 	const struct vdpa_config_ops *config;
86 	struct rw_semaphore cf_lock; /* Protects get/set config */
87 	unsigned int index;
88 	bool features_valid;
89 	bool use_va;
90 	u32 nvqs;
91 	struct vdpa_mgmt_dev *mdev;
92 	unsigned int ngroups;
93 	unsigned int nas;
94 };
95 
96 /**
97  * struct vdpa_iova_range - the IOVA range support by the device
98  * @first: start of the IOVA range
99  * @last: end of the IOVA range
100  */
101 struct vdpa_iova_range {
102 	u64 first;
103 	u64 last;
104 };
105 
106 struct vdpa_dev_set_config {
107 	struct {
108 		u8 mac[ETH_ALEN];
109 		u16 mtu;
110 		u16 max_vq_pairs;
111 	} net;
112 	u64 mask;
113 };
114 
115 /**
116  * Corresponding file area for device memory mapping
117  * @file: vma->vm_file for the mapping
118  * @offset: mapping offset in the vm_file
119  */
120 struct vdpa_map_file {
121 	struct file *file;
122 	u64 offset;
123 };
124 
125 /**
126  * struct vdpa_config_ops - operations for configuring a vDPA device.
127  * Note: vDPA device drivers are required to implement all of the
128  * operations unless it is mentioned to be optional in the following
129  * list.
130  *
131  * @set_vq_address:		Set the address of virtqueue
132  *				@vdev: vdpa device
133  *				@idx: virtqueue index
134  *				@desc_area: address of desc area
135  *				@driver_area: address of driver area
136  *				@device_area: address of device area
137  *				Returns integer: success (0) or error (< 0)
138  * @set_vq_num:			Set the size of virtqueue
139  *				@vdev: vdpa device
140  *				@idx: virtqueue index
141  *				@num: the size of virtqueue
142  * @kick_vq:			Kick the virtqueue
143  *				@vdev: vdpa device
144  *				@idx: virtqueue index
145  * @set_vq_cb:			Set the interrupt callback function for
146  *				a virtqueue
147  *				@vdev: vdpa device
148  *				@idx: virtqueue index
149  *				@cb: virtio-vdev interrupt callback structure
150  * @set_vq_ready:		Set ready status for a virtqueue
151  *				@vdev: vdpa device
152  *				@idx: virtqueue index
153  *				@ready: ready (true) not ready(false)
154  * @get_vq_ready:		Get ready status for a virtqueue
155  *				@vdev: vdpa device
156  *				@idx: virtqueue index
157  *				Returns boolean: ready (true) or not (false)
158  * @set_vq_state:		Set the state for a virtqueue
159  *				@vdev: vdpa device
160  *				@idx: virtqueue index
161  *				@state: pointer to set virtqueue state (last_avail_idx)
162  *				Returns integer: success (0) or error (< 0)
163  * @get_vq_state:		Get the state for a virtqueue
164  *				@vdev: vdpa device
165  *				@idx: virtqueue index
166  *				@state: pointer to returned state (last_avail_idx)
167  * @get_vq_notification:	Get the notification area for a virtqueue (optional)
168  *				@vdev: vdpa device
169  *				@idx: virtqueue index
170  *				Returns the notifcation area
171  * @get_vq_irq:			Get the irq number of a virtqueue (optional,
172  *				but must implemented if require vq irq offloading)
173  *				@vdev: vdpa device
174  *				@idx: virtqueue index
175  *				Returns int: irq number of a virtqueue,
176  *				negative number if no irq assigned.
177  * @get_vq_align:		Get the virtqueue align requirement
178  *				for the device
179  *				@vdev: vdpa device
180  *				Returns virtqueue algin requirement
181  * @get_vq_group:		Get the group id for a specific
182  *				virtqueue (optional)
183  *				@vdev: vdpa device
184  *				@idx: virtqueue index
185  *				Returns u32: group id for this virtqueue
186  * @get_device_features:	Get virtio features supported by the device
187  *				@vdev: vdpa device
188  *				Returns the virtio features support by the
189  *				device
190  * @set_driver_features:	Set virtio features supported by the driver
191  *				@vdev: vdpa device
192  *				@features: feature support by the driver
193  *				Returns integer: success (0) or error (< 0)
194  * @get_driver_features:	Get the virtio driver features in action
195  *				@vdev: vdpa device
196  *				Returns the virtio features accepted
197  * @set_config_cb:		Set the config interrupt callback
198  *				@vdev: vdpa device
199  *				@cb: virtio-vdev interrupt callback structure
200  * @get_vq_num_max:		Get the max size of virtqueue
201  *				@vdev: vdpa device
202  *				Returns u16: max size of virtqueue
203  * @get_vq_num_min:		Get the min size of virtqueue (optional)
204  *				@vdev: vdpa device
205  *				Returns u16: min size of virtqueue
206  * @get_device_id:		Get virtio device id
207  *				@vdev: vdpa device
208  *				Returns u32: virtio device id
209  * @get_vendor_id:		Get id for the vendor that provides this device
210  *				@vdev: vdpa device
211  *				Returns u32: virtio vendor id
212  * @get_status:			Get the device status
213  *				@vdev: vdpa device
214  *				Returns u8: virtio device status
215  * @set_status:			Set the device status
216  *				@vdev: vdpa device
217  *				@status: virtio device status
218  * @reset:			Reset device
219  *				@vdev: vdpa device
220  *				Returns integer: success (0) or error (< 0)
221  * @get_config_size:		Get the size of the configuration space includes
222  *				fields that are conditional on feature bits.
223  *				@vdev: vdpa device
224  *				Returns size_t: configuration size
225  * @get_config:			Read from device specific configuration space
226  *				@vdev: vdpa device
227  *				@offset: offset from the beginning of
228  *				configuration space
229  *				@buf: buffer used to read to
230  *				@len: the length to read from
231  *				configuration space
232  * @set_config:			Write to device specific configuration space
233  *				@vdev: vdpa device
234  *				@offset: offset from the beginning of
235  *				configuration space
236  *				@buf: buffer used to write from
237  *				@len: the length to write to
238  *				configuration space
239  * @get_generation:		Get device config generation (optional)
240  *				@vdev: vdpa device
241  *				Returns u32: device generation
242  * @get_iova_range:		Get supported iova range (optional)
243  *				@vdev: vdpa device
244  *				Returns the iova range supported by
245  *				the device.
246  * @set_group_asid:		Set address space identifier for a
247  *				virtqueue group (optional)
248  *				@vdev: vdpa device
249  *				@group: virtqueue group
250  *				@asid: address space id for this group
251  *				Returns integer: success (0) or error (< 0)
252  * @set_map:			Set device memory mapping (optional)
253  *				Needed for device that using device
254  *				specific DMA translation (on-chip IOMMU)
255  *				@vdev: vdpa device
256  *				@asid: address space identifier
257  *				@iotlb: vhost memory mapping to be
258  *				used by the vDPA
259  *				Returns integer: success (0) or error (< 0)
260  * @dma_map:			Map an area of PA to IOVA (optional)
261  *				Needed for device that using device
262  *				specific DMA translation (on-chip IOMMU)
263  *				and preferring incremental map.
264  *				@vdev: vdpa device
265  *				@asid: address space identifier
266  *				@iova: iova to be mapped
267  *				@size: size of the area
268  *				@pa: physical address for the map
269  *				@perm: device access permission (VHOST_MAP_XX)
270  *				Returns integer: success (0) or error (< 0)
271  * @dma_unmap:			Unmap an area of IOVA (optional but
272  *				must be implemented with dma_map)
273  *				Needed for device that using device
274  *				specific DMA translation (on-chip IOMMU)
275  *				and preferring incremental unmap.
276  *				@vdev: vdpa device
277  *				@asid: address space identifier
278  *				@iova: iova to be unmapped
279  *				@size: size of the area
280  *				Returns integer: success (0) or error (< 0)
281  * @free:			Free resources that belongs to vDPA (optional)
282  *				@vdev: vdpa device
283  */
284 struct vdpa_config_ops {
285 	/* Virtqueue ops */
286 	int (*set_vq_address)(struct vdpa_device *vdev,
287 			      u16 idx, u64 desc_area, u64 driver_area,
288 			      u64 device_area);
289 	void (*set_vq_num)(struct vdpa_device *vdev, u16 idx, u32 num);
290 	void (*kick_vq)(struct vdpa_device *vdev, u16 idx);
291 	void (*set_vq_cb)(struct vdpa_device *vdev, u16 idx,
292 			  struct vdpa_callback *cb);
293 	void (*set_vq_ready)(struct vdpa_device *vdev, u16 idx, bool ready);
294 	bool (*get_vq_ready)(struct vdpa_device *vdev, u16 idx);
295 	int (*set_vq_state)(struct vdpa_device *vdev, u16 idx,
296 			    const struct vdpa_vq_state *state);
297 	int (*get_vq_state)(struct vdpa_device *vdev, u16 idx,
298 			    struct vdpa_vq_state *state);
299 	int (*get_vendor_vq_stats)(struct vdpa_device *vdev, u16 idx,
300 				   struct sk_buff *msg,
301 				   struct netlink_ext_ack *extack);
302 	struct vdpa_notification_area
303 	(*get_vq_notification)(struct vdpa_device *vdev, u16 idx);
304 	/* vq irq is not expected to be changed once DRIVER_OK is set */
305 	int (*get_vq_irq)(struct vdpa_device *vdev, u16 idx);
306 
307 	/* Device ops */
308 	u32 (*get_vq_align)(struct vdpa_device *vdev);
309 	u32 (*get_vq_group)(struct vdpa_device *vdev, u16 idx);
310 	u64 (*get_device_features)(struct vdpa_device *vdev);
311 	int (*set_driver_features)(struct vdpa_device *vdev, u64 features);
312 	u64 (*get_driver_features)(struct vdpa_device *vdev);
313 	void (*set_config_cb)(struct vdpa_device *vdev,
314 			      struct vdpa_callback *cb);
315 	u16 (*get_vq_num_max)(struct vdpa_device *vdev);
316 	u16 (*get_vq_num_min)(struct vdpa_device *vdev);
317 	u32 (*get_device_id)(struct vdpa_device *vdev);
318 	u32 (*get_vendor_id)(struct vdpa_device *vdev);
319 	u8 (*get_status)(struct vdpa_device *vdev);
320 	void (*set_status)(struct vdpa_device *vdev, u8 status);
321 	int (*reset)(struct vdpa_device *vdev);
322 	size_t (*get_config_size)(struct vdpa_device *vdev);
323 	void (*get_config)(struct vdpa_device *vdev, unsigned int offset,
324 			   void *buf, unsigned int len);
325 	void (*set_config)(struct vdpa_device *vdev, unsigned int offset,
326 			   const void *buf, unsigned int len);
327 	u32 (*get_generation)(struct vdpa_device *vdev);
328 	struct vdpa_iova_range (*get_iova_range)(struct vdpa_device *vdev);
329 
330 	/* DMA ops */
331 	int (*set_map)(struct vdpa_device *vdev, unsigned int asid,
332 		       struct vhost_iotlb *iotlb);
333 	int (*dma_map)(struct vdpa_device *vdev, unsigned int asid,
334 		       u64 iova, u64 size, u64 pa, u32 perm, void *opaque);
335 	int (*dma_unmap)(struct vdpa_device *vdev, unsigned int asid,
336 			 u64 iova, u64 size);
337 	int (*set_group_asid)(struct vdpa_device *vdev, unsigned int group,
338 			      unsigned int asid);
339 
340 	/* Free device resources */
341 	void (*free)(struct vdpa_device *vdev);
342 };
343 
344 struct vdpa_device *__vdpa_alloc_device(struct device *parent,
345 					const struct vdpa_config_ops *config,
346 					unsigned int ngroups, unsigned int nas,
347 					size_t size, const char *name,
348 					bool use_va);
349 
350 /**
351  * vdpa_alloc_device - allocate and initilaize a vDPA device
352  *
353  * @dev_struct: the type of the parent structure
354  * @member: the name of struct vdpa_device within the @dev_struct
355  * @parent: the parent device
356  * @config: the bus operations that is supported by this device
357  * @ngroups: the number of virtqueue groups supported by this device
358  * @nas: the number of address spaces
359  * @name: name of the vdpa device
360  * @use_va: indicate whether virtual address must be used by this device
361  *
362  * Return allocated data structure or ERR_PTR upon error
363  */
364 #define vdpa_alloc_device(dev_struct, member, parent, config, ngroups, nas, \
365 			  name, use_va) \
366 			  container_of((__vdpa_alloc_device( \
367 				       parent, config, ngroups, nas, \
368 				       (sizeof(dev_struct) + \
369 				       BUILD_BUG_ON_ZERO(offsetof( \
370 				       dev_struct, member))), name, use_va)), \
371 				       dev_struct, member)
372 
373 int vdpa_register_device(struct vdpa_device *vdev, u32 nvqs);
374 void vdpa_unregister_device(struct vdpa_device *vdev);
375 
376 int _vdpa_register_device(struct vdpa_device *vdev, u32 nvqs);
377 void _vdpa_unregister_device(struct vdpa_device *vdev);
378 
379 /**
380  * struct vdpa_driver - operations for a vDPA driver
381  * @driver: underlying device driver
382  * @probe: the function to call when a device is found.  Returns 0 or -errno.
383  * @remove: the function to call when a device is removed.
384  */
385 struct vdpa_driver {
386 	struct device_driver driver;
387 	int (*probe)(struct vdpa_device *vdev);
388 	void (*remove)(struct vdpa_device *vdev);
389 };
390 
391 #define vdpa_register_driver(drv) \
392 	__vdpa_register_driver(drv, THIS_MODULE)
393 int __vdpa_register_driver(struct vdpa_driver *drv, struct module *owner);
394 void vdpa_unregister_driver(struct vdpa_driver *drv);
395 
396 #define module_vdpa_driver(__vdpa_driver) \
397 	module_driver(__vdpa_driver, vdpa_register_driver,	\
398 		      vdpa_unregister_driver)
399 
drv_to_vdpa(struct device_driver * driver)400 static inline struct vdpa_driver *drv_to_vdpa(struct device_driver *driver)
401 {
402 	return container_of(driver, struct vdpa_driver, driver);
403 }
404 
dev_to_vdpa(struct device * _dev)405 static inline struct vdpa_device *dev_to_vdpa(struct device *_dev)
406 {
407 	return container_of(_dev, struct vdpa_device, dev);
408 }
409 
vdpa_get_drvdata(const struct vdpa_device * vdev)410 static inline void *vdpa_get_drvdata(const struct vdpa_device *vdev)
411 {
412 	return dev_get_drvdata(&vdev->dev);
413 }
414 
vdpa_set_drvdata(struct vdpa_device * vdev,void * data)415 static inline void vdpa_set_drvdata(struct vdpa_device *vdev, void *data)
416 {
417 	dev_set_drvdata(&vdev->dev, data);
418 }
419 
vdpa_get_dma_dev(struct vdpa_device * vdev)420 static inline struct device *vdpa_get_dma_dev(struct vdpa_device *vdev)
421 {
422 	return vdev->dma_dev;
423 }
424 
vdpa_reset(struct vdpa_device * vdev)425 static inline int vdpa_reset(struct vdpa_device *vdev)
426 {
427 	const struct vdpa_config_ops *ops = vdev->config;
428 	int ret;
429 
430 	down_write(&vdev->cf_lock);
431 	vdev->features_valid = false;
432 	ret = ops->reset(vdev);
433 	up_write(&vdev->cf_lock);
434 	return ret;
435 }
436 
vdpa_set_features_unlocked(struct vdpa_device * vdev,u64 features)437 static inline int vdpa_set_features_unlocked(struct vdpa_device *vdev, u64 features)
438 {
439 	const struct vdpa_config_ops *ops = vdev->config;
440 	int ret;
441 
442 	vdev->features_valid = true;
443 	ret = ops->set_driver_features(vdev, features);
444 
445 	return ret;
446 }
447 
vdpa_set_features(struct vdpa_device * vdev,u64 features)448 static inline int vdpa_set_features(struct vdpa_device *vdev, u64 features)
449 {
450 	int ret;
451 
452 	down_write(&vdev->cf_lock);
453 	ret = vdpa_set_features_unlocked(vdev, features);
454 	up_write(&vdev->cf_lock);
455 
456 	return ret;
457 }
458 
459 void vdpa_get_config(struct vdpa_device *vdev, unsigned int offset,
460 		     void *buf, unsigned int len);
461 void vdpa_set_config(struct vdpa_device *dev, unsigned int offset,
462 		     const void *buf, unsigned int length);
463 void vdpa_set_status(struct vdpa_device *vdev, u8 status);
464 
465 /**
466  * struct vdpa_mgmtdev_ops - vdpa device ops
467  * @dev_add: Add a vdpa device using alloc and register
468  *	     @mdev: parent device to use for device addition
469  *	     @name: name of the new vdpa device
470  *	     @config: config attributes to apply to the device under creation
471  *	     Driver need to add a new device using _vdpa_register_device()
472  *	     after fully initializing the vdpa device. Driver must return 0
473  *	     on success or appropriate error code.
474  * @dev_del: Remove a vdpa device using unregister
475  *	     @mdev: parent device to use for device removal
476  *	     @dev: vdpa device to remove
477  *	     Driver need to remove the specified device by calling
478  *	     _vdpa_unregister_device().
479  */
480 struct vdpa_mgmtdev_ops {
481 	int (*dev_add)(struct vdpa_mgmt_dev *mdev, const char *name,
482 		       const struct vdpa_dev_set_config *config);
483 	void (*dev_del)(struct vdpa_mgmt_dev *mdev, struct vdpa_device *dev);
484 };
485 
486 /**
487  * struct vdpa_mgmt_dev - vdpa management device
488  * @device: Management parent device
489  * @ops: operations supported by management device
490  * @id_table: Pointer to device id table of supported ids
491  * @config_attr_mask: bit mask of attributes of type enum vdpa_attr that
492  *		      management device support during dev_add callback
493  * @list: list entry
494  */
495 struct vdpa_mgmt_dev {
496 	struct device *device;
497 	const struct vdpa_mgmtdev_ops *ops;
498 	struct virtio_device_id *id_table;
499 	u64 config_attr_mask;
500 	struct list_head list;
501 	u64 supported_features;
502 	u32 max_supported_vqs;
503 };
504 
505 int vdpa_mgmtdev_register(struct vdpa_mgmt_dev *mdev);
506 void vdpa_mgmtdev_unregister(struct vdpa_mgmt_dev *mdev);
507 
508 #endif /* _LINUX_VDPA_H */
509