include/hw/virtio/virtio.h

   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 enum virtio_device_endian {
  86     VIRTIO_DEVICE_ENDIAN_UNKNOWN,
  87     VIRTIO_DEVICE_ENDIAN_LITTLE,
  88     VIRTIO_DEVICE_ENDIAN_BIG,
  89 };
  90
  91 struct VirtIODevice
  92 {
  93     DeviceState parent_obj;
  94     const char *name;
  95     uint8_t status;
  96     uint8_t isr;
  97     uint16_t queue_sel;
  98     uint64_t guest_features;
  99     uint64_t host_features;
 100     uint64_t backend_features;
 101     size_t config_len;
 102     void *config;
 103     uint16_t config_vector;
 104     uint32_t generation;
 105     int nvectors;
 106     VirtQueue *vq;
 107     MemoryListener listener;
 108     uint16_t device_id;
 109     /* @vm_running: current VM running state via virtio_vmstate_change() */
 110     bool vm_running;
 111     bool broken; /* device in invalid state, needs reset */
 112     bool use_disabled_flag; /* allow use of 'disable' flag when needed */
 113     bool disabled; /* device in temporarily disabled state */
 114     bool use_started;
 115     bool started;
 116     bool start_on_kick; /* when virtio 1.0 feature has not been negotiated */
 117     bool disable_legacy_check;
 118     bool vhost_started;
 119     VMChangeStateEntry *vmstate;
 120     char *bus_name;
 121     uint8_t device_endian;
 122     bool use_guest_notifier_mask;
 123     AddressSpace *dma_as;
 124     QLIST_HEAD(, VirtQueue) *vector_queues;
 125     QTAILQ_ENTRY(VirtIODevice) next;
 126 };
 127
 128 struct VirtioDeviceClass {
 129     /*< private >*/
 130     DeviceClass parent;
 131     /*< public >*/
 132
 133     /* This is what a VirtioDevice must implement */
 134     DeviceRealize realize;
 135     DeviceUnrealize unrealize;
 136     uint64_t (*get_features)(VirtIODevice *vdev,
 137                              uint64_t requested_features,
 138                              Error **errp);
 139     uint64_t (*bad_features)(VirtIODevice *vdev);
 140     void (*set_features)(VirtIODevice *vdev, uint64_t val);
 141     int (*validate_features)(VirtIODevice *vdev);
 142     void (*get_config)(VirtIODevice *vdev, uint8_t *config);
 143     void (*set_config)(VirtIODevice *vdev, const uint8_t *config);
 144     void (*reset)(VirtIODevice *vdev);
 145     void (*set_status)(VirtIODevice *vdev, uint8_t val);
 146     /* For transitional devices, this is a bitmap of features
 147      * that are only exposed on the legacy interface but not
 148      * the modern one.
 149      */
 150     uint64_t legacy_features;
 151     /* Test and clear event pending status.
 152      * Should be called after unmask to avoid losing events.
 153      * If backend does not support masking,
 154      * must check in frontend instead.
 155      */
 156     bool (*guest_notifier_pending)(VirtIODevice *vdev, int n);
 157     /* Mask/unmask events from this vq. Any events reported
 158      * while masked will become pending.
 159      * If backend does not support masking,
 160      * must mask in frontend instead.
 161      */
 162     void (*guest_notifier_mask)(VirtIODevice *vdev, int n, bool mask);
 163     int (*start_ioeventfd)(VirtIODevice *vdev);
 164     void (*stop_ioeventfd)(VirtIODevice *vdev);
 165     /* Saving and loading of a device; trying to deprecate save/load
 166      * use vmsd for new devices.
 167      */
 168     void (*save)(VirtIODevice *vdev, QEMUFile *f);
 169     int (*load)(VirtIODevice *vdev, QEMUFile *f, int version_id);
 170     /* Post load hook in vmsd is called early while device is processed, and
 171      * when VirtIODevice isn't fully initialized.  Devices should use this instead,
 172      * unless they specifically want to verify the migration stream as it's
 173      * processed, e.g. for bounds checking.
 174      */
 175     int (*post_load)(VirtIODevice *vdev);
 176     const VMStateDescription *vmsd;
 177     bool (*primary_unplug_pending)(void *opaque);
 178     struct vhost_dev *(*get_vhost)(VirtIODevice *vdev);
 179 };
 180
 181 void virtio_instance_init_common(Object *proxy_obj, void *data,
 182                                  size_t vdev_size, const char *vdev_name);
 183
 184 void virtio_init(VirtIODevice *vdev, uint16_t device_id, size_t config_size);
 185
 186 void virtio_cleanup(VirtIODevice *vdev);
 187
 188 void virtio_error(VirtIODevice *vdev, const char *fmt, ...) G_GNUC_PRINTF(2, 3);
 189
 190 /* Set the child bus name. */
 191 void virtio_device_set_child_bus_name(VirtIODevice *vdev, char *bus_name);
 192
 193 typedef void (*VirtIOHandleOutput)(VirtIODevice *, VirtQueue *);
 194
 195 VirtQueue *virtio_add_queue(VirtIODevice *vdev, int queue_size,
 196                             VirtIOHandleOutput handle_output);
 197
 198 void virtio_del_queue(VirtIODevice *vdev, int n);
 199
 200 void virtio_delete_queue(VirtQueue *vq);
 201
 202 void virtqueue_push(VirtQueue *vq, const VirtQueueElement *elem,
 203                     unsigned int len);
 204 void virtqueue_flush(VirtQueue *vq, unsigned int count);
 205 void virtqueue_detach_element(VirtQueue *vq, const VirtQueueElement *elem,
 206                               unsigned int len);
 207 void virtqueue_unpop(VirtQueue *vq, const VirtQueueElement *elem,
 208                      unsigned int len);
 209 bool virtqueue_rewind(VirtQueue *vq, unsigned int num);
 210 void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem,
 211                     unsigned int len, unsigned int idx);
 212
 213 void virtqueue_map(VirtIODevice *vdev, VirtQueueElement *elem);
 214 void *virtqueue_pop(VirtQueue *vq, size_t sz);
 215 unsigned int virtqueue_drop_all(VirtQueue *vq);
 216 void *qemu_get_virtqueue_element(VirtIODevice *vdev, QEMUFile *f, size_t sz);
 217 void qemu_put_virtqueue_element(VirtIODevice *vdev, QEMUFile *f,
 218                                 VirtQueueElement *elem);
 219 int virtqueue_avail_bytes(VirtQueue *vq, unsigned int in_bytes,
 220                           unsigned int out_bytes);
 221 void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes,
 222                                unsigned int *out_bytes,
 223                                unsigned max_in_bytes, unsigned max_out_bytes);
 224
 225 void virtio_notify_irqfd(VirtIODevice *vdev, VirtQueue *vq);
 226 void virtio_notify(VirtIODevice *vdev, VirtQueue *vq);
 227
 228 int virtio_save(VirtIODevice *vdev, QEMUFile *f);
 229
 230 extern const VMStateInfo virtio_vmstate_info;
 231
 232 #define VMSTATE_VIRTIO_DEVICE \
 233     {                                         \
 234         .name = "virtio",                     \
 235         .info = &virtio_vmstate_info,         \
 236         .flags = VMS_SINGLE,                  \
 237     }
 238
 239 int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id);
 240
 241 void virtio_notify_config(VirtIODevice *vdev);
 242
 243 bool virtio_queue_get_notification(VirtQueue *vq);
 244 void virtio_queue_set_notification(VirtQueue *vq, int enable);
 245
 246 int virtio_queue_ready(VirtQueue *vq);
 247
 248 int virtio_queue_empty(VirtQueue *vq);
 249
 250 /* Host binding interface.  */
 251
 252 uint32_t virtio_config_readb(VirtIODevice *vdev, uint32_t addr);
 253 uint32_t virtio_config_readw(VirtIODevice *vdev, uint32_t addr);
 254 uint32_t virtio_config_readl(VirtIODevice *vdev, uint32_t addr);
 255 void virtio_config_writeb(VirtIODevice *vdev, uint32_t addr, uint32_t data);
 256 void virtio_config_writew(VirtIODevice *vdev, uint32_t addr, uint32_t data);
 257 void virtio_config_writel(VirtIODevice *vdev, uint32_t addr, uint32_t data);
 258 uint32_t virtio_config_modern_readb(VirtIODevice *vdev, uint32_t addr);
 259 uint32_t virtio_config_modern_readw(VirtIODevice *vdev, uint32_t addr);
 260 uint32_t virtio_config_modern_readl(VirtIODevice *vdev, uint32_t addr);
 261 void virtio_config_modern_writeb(VirtIODevice *vdev,
 262                                  uint32_t addr, uint32_t data);
 263 void virtio_config_modern_writew(VirtIODevice *vdev,
 264                                  uint32_t addr, uint32_t data);
 265 void virtio_config_modern_writel(VirtIODevice *vdev,
 266                                  uint32_t addr, uint32_t data);
 267 void virtio_queue_set_addr(VirtIODevice *vdev, int n, hwaddr addr);
 268 hwaddr virtio_queue_get_addr(VirtIODevice *vdev, int n);
 269 void virtio_queue_set_num(VirtIODevice *vdev, int n, int num);
 270 int virtio_queue_get_num(VirtIODevice *vdev, int n);
 271 int virtio_queue_get_max_num(VirtIODevice *vdev, int n);
 272 int virtio_get_num_queues(VirtIODevice *vdev);
 273 void virtio_queue_set_rings(VirtIODevice *vdev, int n, hwaddr desc,
 274                             hwaddr avail, hwaddr used);
 275 void virtio_queue_update_rings(VirtIODevice *vdev, int n);
 276 void virtio_queue_set_align(VirtIODevice *vdev, int n, int align);
 277 void virtio_queue_notify(VirtIODevice *vdev, int n);
 278 uint16_t virtio_queue_vector(VirtIODevice *vdev, int n);
 279 void virtio_queue_set_vector(VirtIODevice *vdev, int n, uint16_t vector);
 280 int virtio_queue_set_host_notifier_mr(VirtIODevice *vdev, int n,
 281                                       MemoryRegion *mr, bool assign);
 282 int virtio_set_status(VirtIODevice *vdev, uint8_t val);
 283 void virtio_reset(void *opaque);
 284 void virtio_update_irq(VirtIODevice *vdev);
 285 int virtio_set_features(VirtIODevice *vdev, uint64_t val);
 286
 287 /* Base devices.  */
 288 typedef struct VirtIOBlkConf VirtIOBlkConf;
 289 struct virtio_net_conf;
 290 typedef struct virtio_serial_conf virtio_serial_conf;
 291 typedef struct virtio_input_conf virtio_input_conf;
 292 typedef struct VirtIOSCSIConf VirtIOSCSIConf;
 293 typedef struct VirtIORNGConf VirtIORNGConf;
 294
 295 #define DEFINE_VIRTIO_COMMON_FEATURES(_state, _field) \
 296     DEFINE_PROP_BIT64("indirect_desc", _state, _field,    \
 297                       VIRTIO_RING_F_INDIRECT_DESC, true), \
 298     DEFINE_PROP_BIT64("event_idx", _state, _field,        \
 299                       VIRTIO_RING_F_EVENT_IDX, true),     \
 300     DEFINE_PROP_BIT64("notify_on_empty", _state, _field,  \
 301                       VIRTIO_F_NOTIFY_ON_EMPTY, true), \
 302     DEFINE_PROP_BIT64("any_layout", _state, _field, \
 303                       VIRTIO_F_ANY_LAYOUT, true), \
 304     DEFINE_PROP_BIT64("iommu_platform", _state, _field, \
 305                       VIRTIO_F_IOMMU_PLATFORM, false), \
 306     DEFINE_PROP_BIT64("packed", _state, _field, \
 307                       VIRTIO_F_RING_PACKED, false)
 308
 309 hwaddr virtio_queue_get_desc_addr(VirtIODevice *vdev, int n);
 310 bool virtio_queue_enabled_legacy(VirtIODevice *vdev, int n);
 311 bool virtio_queue_enabled(VirtIODevice *vdev, int n);
 312 hwaddr virtio_queue_get_avail_addr(VirtIODevice *vdev, int n);
 313 hwaddr virtio_queue_get_used_addr(VirtIODevice *vdev, int n);
 314 hwaddr virtio_queue_get_desc_size(VirtIODevice *vdev, int n);
 315 hwaddr virtio_queue_get_avail_size(VirtIODevice *vdev, int n);
 316 hwaddr virtio_queue_get_used_size(VirtIODevice *vdev, int n);
 317 unsigned int virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n);
 318 void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n,
 319                                      unsigned int idx);
 320 void virtio_queue_restore_last_avail_idx(VirtIODevice *vdev, int n);
 321 void virtio_queue_invalidate_signalled_used(VirtIODevice *vdev, int n);
 322 void virtio_queue_update_used_idx(VirtIODevice *vdev, int n);
 323 VirtQueue *virtio_get_queue(VirtIODevice *vdev, int n);
 324 uint16_t virtio_get_queue_index(VirtQueue *vq);
 325 EventNotifier *virtio_queue_get_guest_notifier(VirtQueue *vq);
 326 void virtio_queue_set_guest_notifier_fd_handler(VirtQueue *vq, bool assign,
 327                                                 bool with_irqfd);
 328 int virtio_device_start_ioeventfd(VirtIODevice *vdev);
 329 int virtio_device_grab_ioeventfd(VirtIODevice *vdev);
 330 void virtio_device_release_ioeventfd(VirtIODevice *vdev);
 331 bool virtio_device_ioeventfd_enabled(VirtIODevice *vdev);
 332 EventNotifier *virtio_queue_get_host_notifier(VirtQueue *vq);
 333 void virtio_queue_set_host_notifier_enabled(VirtQueue *vq, bool enabled);
 334 void virtio_queue_host_notifier_read(EventNotifier *n);
 335 void virtio_queue_aio_attach_host_notifier(VirtQueue *vq, AioContext *ctx);
 336 void virtio_queue_aio_attach_host_notifier_no_poll(VirtQueue *vq, AioContext *ctx);
 337 void virtio_queue_aio_detach_host_notifier(VirtQueue *vq, AioContext *ctx);
 338 VirtQueue *virtio_vector_first_queue(VirtIODevice *vdev, uint16_t vector);
 339 VirtQueue *virtio_vector_next_queue(VirtQueue *vq);
 340
 341 static inline void virtio_add_feature(uint64_t *features, unsigned int fbit)
 342 {
 343     assert(fbit < 64);
 344     *features |= (1ULL << fbit);
 345 }
 346
 347 static inline void virtio_clear_feature(uint64_t *features, unsigned int fbit)
 348 {
 349     assert(fbit < 64);
 350     *features &= ~(1ULL << fbit);
 351 }
 352
 353 static inline bool virtio_has_feature(uint64_t features, unsigned int fbit)
 354 {
 355     assert(fbit < 64);
 356     return !!(features & (1ULL << fbit));
 357 }
 358
 359 static inline bool virtio_vdev_has_feature(VirtIODevice *vdev,
 360                                            unsigned int fbit)
 361 {
 362     return virtio_has_feature(vdev->guest_features, fbit);
 363 }
 364
 365 static inline bool virtio_host_has_feature(VirtIODevice *vdev,
 366                                            unsigned int fbit)
 367 {
 368     return virtio_has_feature(vdev->host_features, fbit);
 369 }
 370
 371 static inline bool virtio_is_big_endian(VirtIODevice *vdev)
 372 {
 373     if (!virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) {
 374         assert(vdev->device_endian != VIRTIO_DEVICE_ENDIAN_UNKNOWN);
 375         return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG;
 376     }
 377     /* Devices conforming to VIRTIO 1.0 or later are always LE. */
 378     return false;
 379 }
 380
 381 static inline bool virtio_device_started(VirtIODevice *vdev, uint8_t status)
 382 {
 383     if (vdev->use_started) {
 384         return vdev->started;
 385     }
 386
 387     if (!vdev->vm_running) {
 388         return false;
 389     }
 390
 391     return status & VIRTIO_CONFIG_S_DRIVER_OK;
 392 }
 393
 394 static inline void virtio_set_started(VirtIODevice *vdev, bool started)
 395 {
 396     if (started) {
 397         vdev->start_on_kick = false;
 398     }
 399
 400     if (vdev->use_started) {
 401         vdev->started = started;
 402     }
 403 }
 404
 405 static inline void virtio_set_disabled(VirtIODevice *vdev, bool disable)
 406 {
 407     if (vdev->use_disabled_flag) {
 408         vdev->disabled = disable;
 409     }
 410 }
 411
 412 static inline bool virtio_device_disabled(VirtIODevice *vdev)
 413 {
 414     return unlikely(vdev->disabled || vdev->broken);
 415 }
 416
 417 bool virtio_legacy_allowed(VirtIODevice *vdev);
 418 bool virtio_legacy_check_disabled(VirtIODevice *vdev);
 419
 420 #endif