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