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