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