1 #ifndef VHOST_H 2 #define VHOST_H 3 4 #include "hw/virtio/vhost-backend.h" 5 #include "hw/virtio/virtio.h" 6 #include "exec/memory.h" 7 8 #define VHOST_F_DEVICE_IOTLB 63 9 #define VHOST_USER_F_PROTOCOL_FEATURES 30 10 11 /* Generic structures common for any vhost based device. */ 12 13 struct vhost_inflight { 14 int fd; 15 void *addr; 16 uint64_t size; 17 uint64_t offset; 18 uint16_t queue_size; 19 }; 20 21 struct vhost_virtqueue { 22 int kick; 23 int call; 24 void *desc; 25 void *avail; 26 void *used; 27 int num; 28 unsigned long long desc_phys; 29 unsigned desc_size; 30 unsigned long long avail_phys; 31 unsigned avail_size; 32 unsigned long long used_phys; 33 unsigned used_size; 34 EventNotifier masked_notifier; 35 EventNotifier error_notifier; 36 EventNotifier masked_config_notifier; 37 struct vhost_dev *dev; 38 }; 39 40 typedef unsigned long vhost_log_chunk_t; 41 #define VHOST_LOG_PAGE 0x1000 42 #define VHOST_LOG_BITS (8 * sizeof(vhost_log_chunk_t)) 43 #define VHOST_LOG_CHUNK (VHOST_LOG_PAGE * VHOST_LOG_BITS) 44 #define VHOST_INVALID_FEATURE_BIT (0xff) 45 #define VHOST_QUEUE_NUM_CONFIG_INR 0 46 47 struct vhost_log { 48 unsigned long long size; 49 int refcnt; 50 int fd; 51 vhost_log_chunk_t *log; 52 }; 53 54 struct vhost_dev; 55 struct vhost_iommu { 56 struct vhost_dev *hdev; 57 MemoryRegion *mr; 58 hwaddr iommu_offset; 59 IOMMUNotifier n; 60 QLIST_ENTRY(vhost_iommu) iommu_next; 61 }; 62 63 typedef struct VhostDevConfigOps { 64 /* Vhost device config space changed callback 65 */ 66 int (*vhost_dev_config_notifier)(struct vhost_dev *dev); 67 } VhostDevConfigOps; 68 69 struct vhost_memory; 70 71 /** 72 * struct vhost_dev - common vhost_dev structure 73 * @vhost_ops: backend specific ops 74 * @config_ops: ops for config changes (see @vhost_dev_set_config_notifier) 75 */ 76 struct vhost_dev { 77 VirtIODevice *vdev; 78 MemoryListener memory_listener; 79 MemoryListener iommu_listener; 80 struct vhost_memory *mem; 81 int n_mem_sections; 82 MemoryRegionSection *mem_sections; 83 int n_tmp_sections; 84 MemoryRegionSection *tmp_sections; 85 struct vhost_virtqueue *vqs; 86 unsigned int nvqs; 87 /* the first virtqueue which would be used by this vhost dev */ 88 int vq_index; 89 /* one past the last vq index for the virtio device (not vhost) */ 90 int vq_index_end; 91 /* if non-zero, minimum required value for max_queues */ 92 int num_queues; 93 /** 94 * vhost feature handling requires matching the feature set 95 * offered by a backend which may be a subset of the total 96 * features eventually offered to the guest. 97 * 98 * @features: available features provided by the backend 99 * @acked_features: final negotiated features with front-end driver 100 * 101 * @backend_features: this is used in a couple of places to either 102 * store VHOST_USER_F_PROTOCOL_FEATURES to apply to 103 * VHOST_USER_SET_FEATURES or VHOST_NET_F_VIRTIO_NET_HDR. Its 104 * future use should be discouraged and the variable retired as 105 * its easy to confuse with the VirtIO backend_features. 106 */ 107 uint64_t features; 108 uint64_t acked_features; 109 uint64_t backend_features; 110 111 /** 112 * @protocol_features: is the vhost-user only feature set by 113 * VHOST_USER_SET_PROTOCOL_FEATURES. Protocol features are only 114 * negotiated if VHOST_USER_F_PROTOCOL_FEATURES has been offered 115 * by the backend (see @features). 116 */ 117 uint64_t protocol_features; 118 119 uint64_t max_queues; 120 uint64_t backend_cap; 121 /* @started: is the vhost device started? */ 122 bool started; 123 bool log_enabled; 124 uint64_t log_size; 125 Error *migration_blocker; 126 const VhostOps *vhost_ops; 127 void *opaque; 128 struct vhost_log *log; 129 QLIST_ENTRY(vhost_dev) entry; 130 QLIST_HEAD(, vhost_iommu) iommu_list; 131 IOMMUNotifier n; 132 const VhostDevConfigOps *config_ops; 133 }; 134 135 extern const VhostOps kernel_ops; 136 extern const VhostOps user_ops; 137 extern const VhostOps vdpa_ops; 138 139 struct vhost_net { 140 struct vhost_dev dev; 141 struct vhost_virtqueue vqs[2]; 142 int backend; 143 NetClientState *nc; 144 }; 145 146 /** 147 * vhost_dev_init() - initialise the vhost interface 148 * @hdev: the common vhost_dev structure 149 * @opaque: opaque ptr passed to backend (vhost/vhost-user/vdpa) 150 * @backend_type: type of backend 151 * @busyloop_timeout: timeout for polling virtqueue 152 * @errp: error handle 153 * 154 * The initialisation of the vhost device will trigger the 155 * initialisation of the backend and potentially capability 156 * negotiation of backend interface. Configuration of the VirtIO 157 * itself won't happen until the interface is started. 158 * 159 * Return: 0 on success, non-zero on error while setting errp. 160 */ 161 int vhost_dev_init(struct vhost_dev *hdev, void *opaque, 162 VhostBackendType backend_type, 163 uint32_t busyloop_timeout, Error **errp); 164 165 /** 166 * vhost_dev_cleanup() - tear down and cleanup vhost interface 167 * @hdev: the common vhost_dev structure 168 */ 169 void vhost_dev_cleanup(struct vhost_dev *hdev); 170 171 /** 172 * vhost_dev_enable_notifiers() - enable event notifiers 173 * @hdev: common vhost_dev structure 174 * @vdev: the VirtIODevice structure 175 * 176 * Enable notifications directly to the vhost device rather than being 177 * triggered by QEMU itself. Notifications should be enabled before 178 * the vhost device is started via @vhost_dev_start. 179 * 180 * Return: 0 on success, < 0 on error. 181 */ 182 int vhost_dev_enable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev); 183 184 /** 185 * vhost_dev_disable_notifiers - disable event notifications 186 * @hdev: common vhost_dev structure 187 * @vdev: the VirtIODevice structure 188 * 189 * Disable direct notifications to vhost device. 190 */ 191 void vhost_dev_disable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev); 192 bool vhost_config_pending(struct vhost_dev *hdev); 193 void vhost_config_mask(struct vhost_dev *hdev, VirtIODevice *vdev, bool mask); 194 195 /** 196 * vhost_dev_is_started() - report status of vhost device 197 * @hdev: common vhost_dev structure 198 * 199 * Return the started status of the vhost device 200 */ 201 static inline bool vhost_dev_is_started(struct vhost_dev *hdev) 202 { 203 return hdev->started; 204 } 205 206 /** 207 * vhost_dev_start() - start the vhost device 208 * @hdev: common vhost_dev structure 209 * @vdev: the VirtIODevice structure 210 * @vrings: true to have vrings enabled in this call 211 * 212 * Starts the vhost device. From this point VirtIO feature negotiation 213 * can start and the device can start processing VirtIO transactions. 214 * 215 * Return: 0 on success, < 0 on error. 216 */ 217 int vhost_dev_start(struct vhost_dev *hdev, VirtIODevice *vdev, bool vrings); 218 219 /** 220 * vhost_dev_stop() - stop the vhost device 221 * @hdev: common vhost_dev structure 222 * @vdev: the VirtIODevice structure 223 * @vrings: true to have vrings disabled in this call 224 * 225 * Stop the vhost device. After the device is stopped the notifiers 226 * can be disabled (@vhost_dev_disable_notifiers) and the device can 227 * be torn down (@vhost_dev_cleanup). 228 */ 229 void vhost_dev_stop(struct vhost_dev *hdev, VirtIODevice *vdev, bool vrings); 230 231 /** 232 * DOC: vhost device configuration handling 233 * 234 * The VirtIO device configuration space is used for rarely changing 235 * or initialisation time parameters. The configuration can be updated 236 * by either the guest driver or the device itself. If the device can 237 * change the configuration over time the vhost handler should 238 * register a @VhostDevConfigOps structure with 239 * @vhost_dev_set_config_notifier so the guest can be notified. Some 240 * devices register a handler anyway and will signal an error if an 241 * unexpected config change happens. 242 */ 243 244 /** 245 * vhost_dev_get_config() - fetch device configuration 246 * @hdev: common vhost_dev_structure 247 * @config: pointer to device appropriate config structure 248 * @config_len: size of device appropriate config structure 249 * 250 * Return: 0 on success, < 0 on error while setting errp 251 */ 252 int vhost_dev_get_config(struct vhost_dev *hdev, uint8_t *config, 253 uint32_t config_len, Error **errp); 254 255 /** 256 * vhost_dev_set_config() - set device configuration 257 * @hdev: common vhost_dev_structure 258 * @data: pointer to data to set 259 * @offset: offset into configuration space 260 * @size: length of set 261 * @flags: @VhostSetConfigType flags 262 * 263 * By use of @offset/@size a subset of the configuration space can be 264 * written to. The @flags are used to indicate if it is a normal 265 * transaction or related to migration. 266 * 267 * Return: 0 on success, non-zero on error 268 */ 269 int vhost_dev_set_config(struct vhost_dev *dev, const uint8_t *data, 270 uint32_t offset, uint32_t size, uint32_t flags); 271 272 /** 273 * vhost_dev_set_config_notifier() - register VhostDevConfigOps 274 * @hdev: common vhost_dev_structure 275 * @ops: notifier ops 276 * 277 * If the device is expected to change configuration a notifier can be 278 * setup to handle the case. 279 */ 280 void vhost_dev_set_config_notifier(struct vhost_dev *dev, 281 const VhostDevConfigOps *ops); 282 283 284 /* Test and clear masked event pending status. 285 * Should be called after unmask to avoid losing events. 286 */ 287 bool vhost_virtqueue_pending(struct vhost_dev *hdev, int n); 288 289 /* Mask/unmask events from this vq. 290 */ 291 void vhost_virtqueue_mask(struct vhost_dev *hdev, VirtIODevice *vdev, int n, 292 bool mask); 293 294 /** 295 * vhost_get_features() - return a sanitised set of feature bits 296 * @hdev: common vhost_dev structure 297 * @feature_bits: pointer to terminated table of feature bits 298 * @features: original feature set 299 * 300 * This returns a set of features bits that is an intersection of what 301 * is supported by the vhost backend (hdev->features), the supported 302 * feature_bits and the requested feature set. 303 */ 304 uint64_t vhost_get_features(struct vhost_dev *hdev, const int *feature_bits, 305 uint64_t features); 306 307 /** 308 * vhost_ack_features() - set vhost acked_features 309 * @hdev: common vhost_dev structure 310 * @feature_bits: pointer to terminated table of feature bits 311 * @features: requested feature set 312 * 313 * This sets the internal hdev->acked_features to the intersection of 314 * the backends advertised features and the supported feature_bits. 315 */ 316 void vhost_ack_features(struct vhost_dev *hdev, const int *feature_bits, 317 uint64_t features); 318 bool vhost_has_free_slot(void); 319 320 int vhost_net_set_backend(struct vhost_dev *hdev, 321 struct vhost_vring_file *file); 322 323 int vhost_device_iotlb_miss(struct vhost_dev *dev, uint64_t iova, int write); 324 325 int vhost_virtqueue_start(struct vhost_dev *dev, struct VirtIODevice *vdev, 326 struct vhost_virtqueue *vq, unsigned idx); 327 void vhost_virtqueue_stop(struct vhost_dev *dev, struct VirtIODevice *vdev, 328 struct vhost_virtqueue *vq, unsigned idx); 329 330 void vhost_dev_reset_inflight(struct vhost_inflight *inflight); 331 void vhost_dev_free_inflight(struct vhost_inflight *inflight); 332 void vhost_dev_save_inflight(struct vhost_inflight *inflight, QEMUFile *f); 333 int vhost_dev_load_inflight(struct vhost_inflight *inflight, QEMUFile *f); 334 int vhost_dev_prepare_inflight(struct vhost_dev *hdev, VirtIODevice *vdev); 335 int vhost_dev_set_inflight(struct vhost_dev *dev, 336 struct vhost_inflight *inflight); 337 int vhost_dev_get_inflight(struct vhost_dev *dev, uint16_t queue_size, 338 struct vhost_inflight *inflight); 339 #endif 340