1 /* 2 * Virtio Support 3 * 4 * Copyright IBM, Corp. 2007 5 * 6 * Authors: 7 * Anthony Liguori <aliguori@us.ibm.com> 8 * 9 * This work is licensed under the terms of the GNU GPL, version 2. See 10 * the COPYING file in the top-level directory. 11 * 12 */ 13 14 #ifndef QEMU_VIRTIO_H 15 #define QEMU_VIRTIO_H 16 17 #include "exec/memory.h" 18 #include "hw/qdev-core.h" 19 #include "net/net.h" 20 #include "migration/vmstate.h" 21 #include "qemu/event_notifier.h" 22 #include "standard-headers/linux/virtio_config.h" 23 #include "standard-headers/linux/virtio_ring.h" 24 #include "qom/object.h" 25 #include "hw/virtio/vhost.h" 26 27 /* 28 * A guest should never accept this. It implies negotiation is broken 29 * between the driver frontend and the device. This bit is re-used for 30 * vhost-user to advertise VHOST_USER_F_PROTOCOL_FEATURES between QEMU 31 * and a vhost-user backend. 32 */ 33 #define VIRTIO_F_BAD_FEATURE 30 34 35 #define VIRTIO_LEGACY_FEATURES ((0x1ULL << VIRTIO_F_BAD_FEATURE) | \ 36 (0x1ULL << VIRTIO_F_NOTIFY_ON_EMPTY) | \ 37 (0x1ULL << VIRTIO_F_ANY_LAYOUT)) 38 39 struct VirtQueue; 40 41 static inline hwaddr vring_align(hwaddr addr, 42 unsigned long align) 43 { 44 return QEMU_ALIGN_UP(addr, align); 45 } 46 47 typedef struct VirtIOFeature { 48 uint64_t flags; 49 size_t end; 50 } VirtIOFeature; 51 52 typedef struct VirtIOConfigSizeParams { 53 size_t min_size; 54 size_t max_size; 55 const VirtIOFeature *feature_sizes; 56 } VirtIOConfigSizeParams; 57 58 size_t virtio_get_config_size(const VirtIOConfigSizeParams *params, 59 uint64_t host_features); 60 61 typedef struct VirtQueue VirtQueue; 62 63 #define VIRTQUEUE_MAX_SIZE 1024 64 65 typedef struct VirtQueueElement 66 { 67 unsigned int index; 68 unsigned int len; 69 unsigned int ndescs; 70 unsigned int out_num; 71 unsigned int in_num; 72 hwaddr *in_addr; 73 hwaddr *out_addr; 74 struct iovec *in_sg; 75 struct iovec *out_sg; 76 } VirtQueueElement; 77 78 #define VIRTIO_QUEUE_MAX 1024 79 80 #define VIRTIO_NO_VECTOR 0xffff 81 82 #define TYPE_VIRTIO_DEVICE "virtio-device" 83 OBJECT_DECLARE_TYPE(VirtIODevice, VirtioDeviceClass, VIRTIO_DEVICE) 84 85 typedef struct { 86 int virtio_bit; 87 const char *feature_desc; 88 } qmp_virtio_feature_map_t; 89 90 enum virtio_device_endian { 91 VIRTIO_DEVICE_ENDIAN_UNKNOWN, 92 VIRTIO_DEVICE_ENDIAN_LITTLE, 93 VIRTIO_DEVICE_ENDIAN_BIG, 94 }; 95 96 struct VirtIODevice 97 { 98 DeviceState parent_obj; 99 const char *name; 100 uint8_t status; 101 uint8_t isr; 102 uint16_t queue_sel; 103 uint64_t guest_features; 104 uint64_t host_features; 105 uint64_t backend_features; 106 size_t config_len; 107 void *config; 108 uint16_t config_vector; 109 uint32_t generation; 110 int nvectors; 111 VirtQueue *vq; 112 MemoryListener listener; 113 uint16_t device_id; 114 /* @vm_running: current VM running state via virtio_vmstate_change() */ 115 bool vm_running; 116 bool broken; /* device in invalid state, needs reset */ 117 bool use_disabled_flag; /* allow use of 'disable' flag when needed */ 118 bool disabled; /* device in temporarily disabled state */ 119 bool use_started; 120 bool started; 121 bool start_on_kick; /* when virtio 1.0 feature has not been negotiated */ 122 bool disable_legacy_check; 123 bool vhost_started; 124 VMChangeStateEntry *vmstate; 125 char *bus_name; 126 uint8_t device_endian; 127 bool use_guest_notifier_mask; 128 AddressSpace *dma_as; 129 QLIST_HEAD(, VirtQueue) *vector_queues; 130 QTAILQ_ENTRY(VirtIODevice) next; 131 }; 132 133 struct VirtioDeviceClass { 134 /*< private >*/ 135 DeviceClass parent; 136 /*< public >*/ 137 138 /* This is what a VirtioDevice must implement */ 139 DeviceRealize realize; 140 DeviceUnrealize unrealize; 141 uint64_t (*get_features)(VirtIODevice *vdev, 142 uint64_t requested_features, 143 Error **errp); 144 uint64_t (*bad_features)(VirtIODevice *vdev); 145 void (*set_features)(VirtIODevice *vdev, uint64_t val); 146 int (*validate_features)(VirtIODevice *vdev); 147 void (*get_config)(VirtIODevice *vdev, uint8_t *config); 148 void (*set_config)(VirtIODevice *vdev, const uint8_t *config); 149 void (*reset)(VirtIODevice *vdev); 150 void (*set_status)(VirtIODevice *vdev, uint8_t val); 151 /* Device must validate queue_index. */ 152 void (*queue_reset)(VirtIODevice *vdev, uint32_t queue_index); 153 /* Device must validate queue_index. */ 154 void (*queue_enable)(VirtIODevice *vdev, uint32_t queue_index); 155 /* For transitional devices, this is a bitmap of features 156 * that are only exposed on the legacy interface but not 157 * the modern one. 158 */ 159 uint64_t legacy_features; 160 /* Test and clear event pending status. 161 * Should be called after unmask to avoid losing events. 162 * If backend does not support masking, 163 * must check in frontend instead. 164 */ 165 bool (*guest_notifier_pending)(VirtIODevice *vdev, int n); 166 /* Mask/unmask events from this vq. Any events reported 167 * while masked will become pending. 168 * If backend does not support masking, 169 * must mask in frontend instead. 170 */ 171 void (*guest_notifier_mask)(VirtIODevice *vdev, int n, bool mask); 172 int (*start_ioeventfd)(VirtIODevice *vdev); 173 void (*stop_ioeventfd)(VirtIODevice *vdev); 174 /* Saving and loading of a device; trying to deprecate save/load 175 * use vmsd for new devices. 176 */ 177 void (*save)(VirtIODevice *vdev, QEMUFile *f); 178 int (*load)(VirtIODevice *vdev, QEMUFile *f, int version_id); 179 /* Post load hook in vmsd is called early while device is processed, and 180 * when VirtIODevice isn't fully initialized. Devices should use this instead, 181 * unless they specifically want to verify the migration stream as it's 182 * processed, e.g. for bounds checking. 183 */ 184 int (*post_load)(VirtIODevice *vdev); 185 const VMStateDescription *vmsd; 186 bool (*primary_unplug_pending)(void *opaque); 187 struct vhost_dev *(*get_vhost)(VirtIODevice *vdev); 188 }; 189 190 void virtio_instance_init_common(Object *proxy_obj, void *data, 191 size_t vdev_size, const char *vdev_name); 192 193 void virtio_init(VirtIODevice *vdev, uint16_t device_id, size_t config_size); 194 195 void virtio_cleanup(VirtIODevice *vdev); 196 197 void virtio_error(VirtIODevice *vdev, const char *fmt, ...) G_GNUC_PRINTF(2, 3); 198 199 /* Set the child bus name. */ 200 void virtio_device_set_child_bus_name(VirtIODevice *vdev, char *bus_name); 201 202 typedef void (*VirtIOHandleOutput)(VirtIODevice *, VirtQueue *); 203 204 VirtQueue *virtio_add_queue(VirtIODevice *vdev, int queue_size, 205 VirtIOHandleOutput handle_output); 206 207 void virtio_del_queue(VirtIODevice *vdev, int n); 208 209 void virtio_delete_queue(VirtQueue *vq); 210 211 void virtqueue_push(VirtQueue *vq, const VirtQueueElement *elem, 212 unsigned int len); 213 void virtqueue_flush(VirtQueue *vq, unsigned int count); 214 void virtqueue_detach_element(VirtQueue *vq, const VirtQueueElement *elem, 215 unsigned int len); 216 void virtqueue_unpop(VirtQueue *vq, const VirtQueueElement *elem, 217 unsigned int len); 218 bool virtqueue_rewind(VirtQueue *vq, unsigned int num); 219 void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem, 220 unsigned int len, unsigned int idx); 221 222 void virtqueue_map(VirtIODevice *vdev, VirtQueueElement *elem); 223 void *virtqueue_pop(VirtQueue *vq, size_t sz); 224 unsigned int virtqueue_drop_all(VirtQueue *vq); 225 void *qemu_get_virtqueue_element(VirtIODevice *vdev, QEMUFile *f, size_t sz); 226 void qemu_put_virtqueue_element(VirtIODevice *vdev, QEMUFile *f, 227 VirtQueueElement *elem); 228 int virtqueue_avail_bytes(VirtQueue *vq, unsigned int in_bytes, 229 unsigned int out_bytes); 230 void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes, 231 unsigned int *out_bytes, 232 unsigned max_in_bytes, unsigned max_out_bytes); 233 234 void virtio_notify_irqfd(VirtIODevice *vdev, VirtQueue *vq); 235 void virtio_notify(VirtIODevice *vdev, VirtQueue *vq); 236 237 int virtio_save(VirtIODevice *vdev, QEMUFile *f); 238 239 extern const VMStateInfo virtio_vmstate_info; 240 241 #define VMSTATE_VIRTIO_DEVICE \ 242 { \ 243 .name = "virtio", \ 244 .info = &virtio_vmstate_info, \ 245 .flags = VMS_SINGLE, \ 246 } 247 248 int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id); 249 250 void virtio_notify_config(VirtIODevice *vdev); 251 252 bool virtio_queue_get_notification(VirtQueue *vq); 253 void virtio_queue_set_notification(VirtQueue *vq, int enable); 254 255 int virtio_queue_ready(VirtQueue *vq); 256 257 int virtio_queue_empty(VirtQueue *vq); 258 259 /* Host binding interface. */ 260 261 uint32_t virtio_config_readb(VirtIODevice *vdev, uint32_t addr); 262 uint32_t virtio_config_readw(VirtIODevice *vdev, uint32_t addr); 263 uint32_t virtio_config_readl(VirtIODevice *vdev, uint32_t addr); 264 void virtio_config_writeb(VirtIODevice *vdev, uint32_t addr, uint32_t data); 265 void virtio_config_writew(VirtIODevice *vdev, uint32_t addr, uint32_t data); 266 void virtio_config_writel(VirtIODevice *vdev, uint32_t addr, uint32_t data); 267 uint32_t virtio_config_modern_readb(VirtIODevice *vdev, uint32_t addr); 268 uint32_t virtio_config_modern_readw(VirtIODevice *vdev, uint32_t addr); 269 uint32_t virtio_config_modern_readl(VirtIODevice *vdev, uint32_t addr); 270 void virtio_config_modern_writeb(VirtIODevice *vdev, 271 uint32_t addr, uint32_t data); 272 void virtio_config_modern_writew(VirtIODevice *vdev, 273 uint32_t addr, uint32_t data); 274 void virtio_config_modern_writel(VirtIODevice *vdev, 275 uint32_t addr, uint32_t data); 276 void virtio_queue_set_addr(VirtIODevice *vdev, int n, hwaddr addr); 277 hwaddr virtio_queue_get_addr(VirtIODevice *vdev, int n); 278 void virtio_queue_set_num(VirtIODevice *vdev, int n, int num); 279 int virtio_queue_get_num(VirtIODevice *vdev, int n); 280 int virtio_queue_get_max_num(VirtIODevice *vdev, int n); 281 int virtio_get_num_queues(VirtIODevice *vdev); 282 void virtio_queue_set_rings(VirtIODevice *vdev, int n, hwaddr desc, 283 hwaddr avail, hwaddr used); 284 void virtio_queue_update_rings(VirtIODevice *vdev, int n); 285 void virtio_queue_set_align(VirtIODevice *vdev, int n, int align); 286 void virtio_queue_notify(VirtIODevice *vdev, int n); 287 uint16_t virtio_queue_vector(VirtIODevice *vdev, int n); 288 void virtio_queue_set_vector(VirtIODevice *vdev, int n, uint16_t vector); 289 int virtio_queue_set_host_notifier_mr(VirtIODevice *vdev, int n, 290 MemoryRegion *mr, bool assign); 291 int virtio_set_status(VirtIODevice *vdev, uint8_t val); 292 void virtio_reset(void *opaque); 293 void virtio_queue_reset(VirtIODevice *vdev, uint32_t queue_index); 294 void virtio_queue_enable(VirtIODevice *vdev, uint32_t queue_index); 295 void virtio_update_irq(VirtIODevice *vdev); 296 int virtio_set_features(VirtIODevice *vdev, uint64_t val); 297 298 /* Base devices. */ 299 typedef struct VirtIOBlkConf VirtIOBlkConf; 300 struct virtio_net_conf; 301 typedef struct virtio_serial_conf virtio_serial_conf; 302 typedef struct virtio_input_conf virtio_input_conf; 303 typedef struct VirtIOSCSIConf VirtIOSCSIConf; 304 typedef struct VirtIORNGConf VirtIORNGConf; 305 306 #define DEFINE_VIRTIO_COMMON_FEATURES(_state, _field) \ 307 DEFINE_PROP_BIT64("indirect_desc", _state, _field, \ 308 VIRTIO_RING_F_INDIRECT_DESC, true), \ 309 DEFINE_PROP_BIT64("event_idx", _state, _field, \ 310 VIRTIO_RING_F_EVENT_IDX, true), \ 311 DEFINE_PROP_BIT64("notify_on_empty", _state, _field, \ 312 VIRTIO_F_NOTIFY_ON_EMPTY, true), \ 313 DEFINE_PROP_BIT64("any_layout", _state, _field, \ 314 VIRTIO_F_ANY_LAYOUT, true), \ 315 DEFINE_PROP_BIT64("iommu_platform", _state, _field, \ 316 VIRTIO_F_IOMMU_PLATFORM, false), \ 317 DEFINE_PROP_BIT64("packed", _state, _field, \ 318 VIRTIO_F_RING_PACKED, false), \ 319 DEFINE_PROP_BIT64("queue_reset", _state, _field, \ 320 VIRTIO_F_RING_RESET, true) 321 322 hwaddr virtio_queue_get_desc_addr(VirtIODevice *vdev, int n); 323 bool virtio_queue_enabled_legacy(VirtIODevice *vdev, int n); 324 bool virtio_queue_enabled(VirtIODevice *vdev, int n); 325 hwaddr virtio_queue_get_avail_addr(VirtIODevice *vdev, int n); 326 hwaddr virtio_queue_get_used_addr(VirtIODevice *vdev, int n); 327 hwaddr virtio_queue_get_desc_size(VirtIODevice *vdev, int n); 328 hwaddr virtio_queue_get_avail_size(VirtIODevice *vdev, int n); 329 hwaddr virtio_queue_get_used_size(VirtIODevice *vdev, int n); 330 unsigned int virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n); 331 void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, 332 unsigned int idx); 333 void virtio_queue_restore_last_avail_idx(VirtIODevice *vdev, int n); 334 void virtio_queue_invalidate_signalled_used(VirtIODevice *vdev, int n); 335 void virtio_queue_update_used_idx(VirtIODevice *vdev, int n); 336 VirtQueue *virtio_get_queue(VirtIODevice *vdev, int n); 337 uint16_t virtio_get_queue_index(VirtQueue *vq); 338 EventNotifier *virtio_queue_get_guest_notifier(VirtQueue *vq); 339 void virtio_queue_set_guest_notifier_fd_handler(VirtQueue *vq, bool assign, 340 bool with_irqfd); 341 int virtio_device_start_ioeventfd(VirtIODevice *vdev); 342 int virtio_device_grab_ioeventfd(VirtIODevice *vdev); 343 void virtio_device_release_ioeventfd(VirtIODevice *vdev); 344 bool virtio_device_ioeventfd_enabled(VirtIODevice *vdev); 345 EventNotifier *virtio_queue_get_host_notifier(VirtQueue *vq); 346 void virtio_queue_set_host_notifier_enabled(VirtQueue *vq, bool enabled); 347 void virtio_queue_host_notifier_read(EventNotifier *n); 348 void virtio_queue_aio_attach_host_notifier(VirtQueue *vq, AioContext *ctx); 349 void virtio_queue_aio_attach_host_notifier_no_poll(VirtQueue *vq, AioContext *ctx); 350 void virtio_queue_aio_detach_host_notifier(VirtQueue *vq, AioContext *ctx); 351 VirtQueue *virtio_vector_first_queue(VirtIODevice *vdev, uint16_t vector); 352 VirtQueue *virtio_vector_next_queue(VirtQueue *vq); 353 354 static inline void virtio_add_feature(uint64_t *features, unsigned int fbit) 355 { 356 assert(fbit < 64); 357 *features |= (1ULL << fbit); 358 } 359 360 static inline void virtio_clear_feature(uint64_t *features, unsigned int fbit) 361 { 362 assert(fbit < 64); 363 *features &= ~(1ULL << fbit); 364 } 365 366 static inline bool virtio_has_feature(uint64_t features, unsigned int fbit) 367 { 368 assert(fbit < 64); 369 return !!(features & (1ULL << fbit)); 370 } 371 372 static inline bool virtio_vdev_has_feature(VirtIODevice *vdev, 373 unsigned int fbit) 374 { 375 return virtio_has_feature(vdev->guest_features, fbit); 376 } 377 378 static inline bool virtio_host_has_feature(VirtIODevice *vdev, 379 unsigned int fbit) 380 { 381 return virtio_has_feature(vdev->host_features, fbit); 382 } 383 384 static inline bool virtio_is_big_endian(VirtIODevice *vdev) 385 { 386 if (!virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) { 387 assert(vdev->device_endian != VIRTIO_DEVICE_ENDIAN_UNKNOWN); 388 return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG; 389 } 390 /* Devices conforming to VIRTIO 1.0 or later are always LE. */ 391 return false; 392 } 393 394 static inline bool virtio_device_started(VirtIODevice *vdev, uint8_t status) 395 { 396 if (vdev->use_started) { 397 return vdev->started; 398 } 399 400 return status & VIRTIO_CONFIG_S_DRIVER_OK; 401 } 402 403 /** 404 * virtio_device_should_start() - check if device startable 405 * @vdev - the VirtIO device 406 * @status - the devices status bits 407 * 408 * This is similar to virtio_device_started() but also encapsulates a 409 * check on the VM status which would prevent a device starting 410 * anyway. 411 */ 412 static inline bool virtio_device_should_start(VirtIODevice *vdev, uint8_t status) 413 { 414 if (vdev->use_started) { 415 return vdev->started; 416 } 417 418 if (!vdev->vm_running) { 419 return false; 420 } 421 422 return status & VIRTIO_CONFIG_S_DRIVER_OK; 423 } 424 425 static inline void virtio_set_started(VirtIODevice *vdev, bool started) 426 { 427 if (started) { 428 vdev->start_on_kick = false; 429 } 430 431 if (vdev->use_started) { 432 vdev->started = started; 433 } 434 } 435 436 static inline void virtio_set_disabled(VirtIODevice *vdev, bool disable) 437 { 438 if (vdev->use_disabled_flag) { 439 vdev->disabled = disable; 440 } 441 } 442 443 static inline bool virtio_device_disabled(VirtIODevice *vdev) 444 { 445 return unlikely(vdev->disabled || vdev->broken); 446 } 447 448 bool virtio_legacy_allowed(VirtIODevice *vdev); 449 bool virtio_legacy_check_disabled(VirtIODevice *vdev); 450 451 #endif 452