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 10 /** 11 * struct vdpa_calllback - vDPA callback definition. 12 * @callback: interrupt callback function 13 * @private: the data passed to the callback function 14 */ 15 struct vdpa_callback { 16 irqreturn_t (*callback)(void *data); 17 void *private; 18 }; 19 20 /** 21 * struct vdpa_notification_area - vDPA notification area 22 * @addr: base address of the notification area 23 * @size: size of the notification area 24 */ 25 struct vdpa_notification_area { 26 resource_size_t addr; 27 resource_size_t size; 28 }; 29 30 /** 31 * struct vdpa_vq_state_split - vDPA split virtqueue state 32 * @avail_index: available index 33 */ 34 struct vdpa_vq_state_split { 35 u16 avail_index; 36 }; 37 38 /** 39 * struct vdpa_vq_state_packed - vDPA packed virtqueue state 40 * @last_avail_counter: last driver ring wrap counter observed by device 41 * @last_avail_idx: device available index 42 * @last_used_counter: device ring wrap counter 43 * @last_used_idx: used index 44 */ 45 struct vdpa_vq_state_packed { 46 u16 last_avail_counter:1; 47 u16 last_avail_idx:15; 48 u16 last_used_counter:1; 49 u16 last_used_idx:15; 50 }; 51 52 struct vdpa_vq_state { 53 union { 54 struct vdpa_vq_state_split split; 55 struct vdpa_vq_state_packed packed; 56 }; 57 }; 58 59 struct vdpa_mgmt_dev; 60 61 /** 62 * struct vdpa_device - representation of a vDPA device 63 * @dev: underlying device 64 * @dma_dev: the actual device that is performing DMA 65 * @config: the configuration ops for this device. 66 * @index: device index 67 * @features_valid: were features initialized? for legacy guests 68 * @nvqs: maximum number of supported virtqueues 69 * @mdev: management device pointer; caller must setup when registering device as part 70 * of dev_add() mgmtdev ops callback before invoking _vdpa_register_device(). 71 */ 72 struct vdpa_device { 73 struct device dev; 74 struct device *dma_dev; 75 const struct vdpa_config_ops *config; 76 unsigned int index; 77 bool features_valid; 78 int nvqs; 79 struct vdpa_mgmt_dev *mdev; 80 }; 81 82 /** 83 * struct vdpa_iova_range - the IOVA range support by the device 84 * @first: start of the IOVA range 85 * @last: end of the IOVA range 86 */ 87 struct vdpa_iova_range { 88 u64 first; 89 u64 last; 90 }; 91 92 /** 93 * struct vdpa_config_ops - operations for configuring a vDPA device. 94 * Note: vDPA device drivers are required to implement all of the 95 * operations unless it is mentioned to be optional in the following 96 * list. 97 * 98 * @set_vq_address: Set the address of virtqueue 99 * @vdev: vdpa device 100 * @idx: virtqueue index 101 * @desc_area: address of desc area 102 * @driver_area: address of driver area 103 * @device_area: address of device area 104 * Returns integer: success (0) or error (< 0) 105 * @set_vq_num: Set the size of virtqueue 106 * @vdev: vdpa device 107 * @idx: virtqueue index 108 * @num: the size of virtqueue 109 * @kick_vq: Kick the virtqueue 110 * @vdev: vdpa device 111 * @idx: virtqueue index 112 * @set_vq_cb: Set the interrupt callback function for 113 * a virtqueue 114 * @vdev: vdpa device 115 * @idx: virtqueue index 116 * @cb: virtio-vdev interrupt callback structure 117 * @set_vq_ready: Set ready status for a virtqueue 118 * @vdev: vdpa device 119 * @idx: virtqueue index 120 * @ready: ready (true) not ready(false) 121 * @get_vq_ready: Get ready status for a virtqueue 122 * @vdev: vdpa device 123 * @idx: virtqueue index 124 * Returns boolean: ready (true) or not (false) 125 * @set_vq_state: Set the state for a virtqueue 126 * @vdev: vdpa device 127 * @idx: virtqueue index 128 * @state: pointer to set virtqueue state (last_avail_idx) 129 * Returns integer: success (0) or error (< 0) 130 * @get_vq_state: Get the state for a virtqueue 131 * @vdev: vdpa device 132 * @idx: virtqueue index 133 * @state: pointer to returned state (last_avail_idx) 134 * @get_vq_notification: Get the notification area for a virtqueue 135 * @vdev: vdpa device 136 * @idx: virtqueue index 137 * Returns the notifcation area 138 * @get_vq_irq: Get the irq number of a virtqueue (optional, 139 * but must implemented if require vq irq offloading) 140 * @vdev: vdpa device 141 * @idx: virtqueue index 142 * Returns int: irq number of a virtqueue, 143 * negative number if no irq assigned. 144 * @get_vq_align: Get the virtqueue align requirement 145 * for the device 146 * @vdev: vdpa device 147 * Returns virtqueue algin requirement 148 * @get_features: Get virtio features supported by the device 149 * @vdev: vdpa device 150 * Returns the virtio features support by the 151 * device 152 * @set_features: Set virtio features supported by the driver 153 * @vdev: vdpa device 154 * @features: feature support by the driver 155 * Returns integer: success (0) or error (< 0) 156 * @set_config_cb: Set the config interrupt callback 157 * @vdev: vdpa device 158 * @cb: virtio-vdev interrupt callback structure 159 * @get_vq_num_max: Get the max size of virtqueue 160 * @vdev: vdpa device 161 * Returns u16: max size of virtqueue 162 * @get_device_id: Get virtio device id 163 * @vdev: vdpa device 164 * Returns u32: virtio device id 165 * @get_vendor_id: Get id for the vendor that provides this device 166 * @vdev: vdpa device 167 * Returns u32: virtio vendor id 168 * @get_status: Get the device status 169 * @vdev: vdpa device 170 * Returns u8: virtio device status 171 * @set_status: Set the device status 172 * @vdev: vdpa device 173 * @status: virtio device status 174 * @get_config_size: Get the size of the configuration space 175 * @vdev: vdpa device 176 * Returns size_t: configuration size 177 * @get_config: Read from device specific configuration space 178 * @vdev: vdpa device 179 * @offset: offset from the beginning of 180 * configuration space 181 * @buf: buffer used to read to 182 * @len: the length to read from 183 * configuration space 184 * @set_config: Write to device specific configuration space 185 * @vdev: vdpa device 186 * @offset: offset from the beginning of 187 * configuration space 188 * @buf: buffer used to write from 189 * @len: the length to write to 190 * configuration space 191 * @get_generation: Get device config generation (optional) 192 * @vdev: vdpa device 193 * Returns u32: device generation 194 * @get_iova_range: Get supported iova range (optional) 195 * @vdev: vdpa device 196 * Returns the iova range supported by 197 * the device. 198 * @set_map: Set device memory mapping (optional) 199 * Needed for device that using device 200 * specific DMA translation (on-chip IOMMU) 201 * @vdev: vdpa device 202 * @iotlb: vhost memory mapping to be 203 * used by the vDPA 204 * Returns integer: success (0) or error (< 0) 205 * @dma_map: Map an area of PA to IOVA (optional) 206 * Needed for device that using device 207 * specific DMA translation (on-chip IOMMU) 208 * and preferring incremental map. 209 * @vdev: vdpa device 210 * @iova: iova to be mapped 211 * @size: size of the area 212 * @pa: physical address for the map 213 * @perm: device access permission (VHOST_MAP_XX) 214 * Returns integer: success (0) or error (< 0) 215 * @dma_unmap: Unmap an area of IOVA (optional but 216 * must be implemented with dma_map) 217 * Needed for device that using device 218 * specific DMA translation (on-chip IOMMU) 219 * and preferring incremental unmap. 220 * @vdev: vdpa device 221 * @iova: iova to be unmapped 222 * @size: size of the area 223 * Returns integer: success (0) or error (< 0) 224 * @free: Free resources that belongs to vDPA (optional) 225 * @vdev: vdpa device 226 */ 227 struct vdpa_config_ops { 228 /* Virtqueue ops */ 229 int (*set_vq_address)(struct vdpa_device *vdev, 230 u16 idx, u64 desc_area, u64 driver_area, 231 u64 device_area); 232 void (*set_vq_num)(struct vdpa_device *vdev, u16 idx, u32 num); 233 void (*kick_vq)(struct vdpa_device *vdev, u16 idx); 234 void (*set_vq_cb)(struct vdpa_device *vdev, u16 idx, 235 struct vdpa_callback *cb); 236 void (*set_vq_ready)(struct vdpa_device *vdev, u16 idx, bool ready); 237 bool (*get_vq_ready)(struct vdpa_device *vdev, u16 idx); 238 int (*set_vq_state)(struct vdpa_device *vdev, u16 idx, 239 const struct vdpa_vq_state *state); 240 int (*get_vq_state)(struct vdpa_device *vdev, u16 idx, 241 struct vdpa_vq_state *state); 242 struct vdpa_notification_area 243 (*get_vq_notification)(struct vdpa_device *vdev, u16 idx); 244 /* vq irq is not expected to be changed once DRIVER_OK is set */ 245 int (*get_vq_irq)(struct vdpa_device *vdv, u16 idx); 246 247 /* Device ops */ 248 u32 (*get_vq_align)(struct vdpa_device *vdev); 249 u64 (*get_features)(struct vdpa_device *vdev); 250 int (*set_features)(struct vdpa_device *vdev, u64 features); 251 void (*set_config_cb)(struct vdpa_device *vdev, 252 struct vdpa_callback *cb); 253 u16 (*get_vq_num_max)(struct vdpa_device *vdev); 254 u32 (*get_device_id)(struct vdpa_device *vdev); 255 u32 (*get_vendor_id)(struct vdpa_device *vdev); 256 u8 (*get_status)(struct vdpa_device *vdev); 257 void (*set_status)(struct vdpa_device *vdev, u8 status); 258 size_t (*get_config_size)(struct vdpa_device *vdev); 259 void (*get_config)(struct vdpa_device *vdev, unsigned int offset, 260 void *buf, unsigned int len); 261 void (*set_config)(struct vdpa_device *vdev, unsigned int offset, 262 const void *buf, unsigned int len); 263 u32 (*get_generation)(struct vdpa_device *vdev); 264 struct vdpa_iova_range (*get_iova_range)(struct vdpa_device *vdev); 265 266 /* DMA ops */ 267 int (*set_map)(struct vdpa_device *vdev, struct vhost_iotlb *iotlb); 268 int (*dma_map)(struct vdpa_device *vdev, u64 iova, u64 size, 269 u64 pa, u32 perm); 270 int (*dma_unmap)(struct vdpa_device *vdev, u64 iova, u64 size); 271 272 /* Free device resources */ 273 void (*free)(struct vdpa_device *vdev); 274 }; 275 276 struct vdpa_device *__vdpa_alloc_device(struct device *parent, 277 const struct vdpa_config_ops *config, 278 size_t size, const char *name); 279 280 #define vdpa_alloc_device(dev_struct, member, parent, config, name) \ 281 container_of(__vdpa_alloc_device( \ 282 parent, config, \ 283 sizeof(dev_struct) + \ 284 BUILD_BUG_ON_ZERO(offsetof( \ 285 dev_struct, member)), name), \ 286 dev_struct, member) 287 288 int vdpa_register_device(struct vdpa_device *vdev, int nvqs); 289 void vdpa_unregister_device(struct vdpa_device *vdev); 290 291 int _vdpa_register_device(struct vdpa_device *vdev, int nvqs); 292 void _vdpa_unregister_device(struct vdpa_device *vdev); 293 294 /** 295 * struct vdpa_driver - operations for a vDPA driver 296 * @driver: underlying device driver 297 * @probe: the function to call when a device is found. Returns 0 or -errno. 298 * @remove: the function to call when a device is removed. 299 */ 300 struct vdpa_driver { 301 struct device_driver driver; 302 int (*probe)(struct vdpa_device *vdev); 303 void (*remove)(struct vdpa_device *vdev); 304 }; 305 306 #define vdpa_register_driver(drv) \ 307 __vdpa_register_driver(drv, THIS_MODULE) 308 int __vdpa_register_driver(struct vdpa_driver *drv, struct module *owner); 309 void vdpa_unregister_driver(struct vdpa_driver *drv); 310 311 #define module_vdpa_driver(__vdpa_driver) \ 312 module_driver(__vdpa_driver, vdpa_register_driver, \ 313 vdpa_unregister_driver) 314 315 static inline struct vdpa_driver *drv_to_vdpa(struct device_driver *driver) 316 { 317 return container_of(driver, struct vdpa_driver, driver); 318 } 319 320 static inline struct vdpa_device *dev_to_vdpa(struct device *_dev) 321 { 322 return container_of(_dev, struct vdpa_device, dev); 323 } 324 325 static inline void *vdpa_get_drvdata(const struct vdpa_device *vdev) 326 { 327 return dev_get_drvdata(&vdev->dev); 328 } 329 330 static inline void vdpa_set_drvdata(struct vdpa_device *vdev, void *data) 331 { 332 dev_set_drvdata(&vdev->dev, data); 333 } 334 335 static inline struct device *vdpa_get_dma_dev(struct vdpa_device *vdev) 336 { 337 return vdev->dma_dev; 338 } 339 340 static inline void vdpa_reset(struct vdpa_device *vdev) 341 { 342 const struct vdpa_config_ops *ops = vdev->config; 343 344 vdev->features_valid = false; 345 ops->set_status(vdev, 0); 346 } 347 348 static inline int vdpa_set_features(struct vdpa_device *vdev, u64 features) 349 { 350 const struct vdpa_config_ops *ops = vdev->config; 351 352 vdev->features_valid = true; 353 return ops->set_features(vdev, features); 354 } 355 356 357 static inline void vdpa_get_config(struct vdpa_device *vdev, unsigned offset, 358 void *buf, unsigned int len) 359 { 360 const struct vdpa_config_ops *ops = vdev->config; 361 362 /* 363 * Config accesses aren't supposed to trigger before features are set. 364 * If it does happen we assume a legacy guest. 365 */ 366 if (!vdev->features_valid) 367 vdpa_set_features(vdev, 0); 368 ops->get_config(vdev, offset, buf, len); 369 } 370 371 /** 372 * struct vdpa_mgmtdev_ops - vdpa device ops 373 * @dev_add: Add a vdpa device using alloc and register 374 * @mdev: parent device to use for device addition 375 * @name: name of the new vdpa device 376 * Driver need to add a new device using _vdpa_register_device() 377 * after fully initializing the vdpa device. Driver must return 0 378 * on success or appropriate error code. 379 * @dev_del: Remove a vdpa device using unregister 380 * @mdev: parent device to use for device removal 381 * @dev: vdpa device to remove 382 * Driver need to remove the specified device by calling 383 * _vdpa_unregister_device(). 384 */ 385 struct vdpa_mgmtdev_ops { 386 int (*dev_add)(struct vdpa_mgmt_dev *mdev, const char *name); 387 void (*dev_del)(struct vdpa_mgmt_dev *mdev, struct vdpa_device *dev); 388 }; 389 390 struct vdpa_mgmt_dev { 391 struct device *device; 392 const struct vdpa_mgmtdev_ops *ops; 393 const struct virtio_device_id *id_table; /* supported ids */ 394 struct list_head list; 395 }; 396 397 int vdpa_mgmtdev_register(struct vdpa_mgmt_dev *mdev); 398 void vdpa_mgmtdev_unregister(struct vdpa_mgmt_dev *mdev); 399 400 #endif /* _LINUX_VDPA_H */ 401