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 #include "qemu/osdep.h" 15 #include "qapi/error.h" 16 #include "qapi/qmp/qdict.h" 17 #include "qapi/qapi-commands-virtio.h" 18 #include "qapi/qapi-commands-qom.h" 19 #include "qapi/qapi-visit-virtio.h" 20 #include "qapi/qmp/qjson.h" 21 #include "cpu.h" 22 #include "trace.h" 23 #include "qemu/error-report.h" 24 #include "qemu/log.h" 25 #include "qemu/main-loop.h" 26 #include "qemu/module.h" 27 #include "qom/object_interfaces.h" 28 #include "hw/virtio/virtio.h" 29 #include "migration/qemu-file-types.h" 30 #include "qemu/atomic.h" 31 #include "hw/virtio/virtio-bus.h" 32 #include "hw/qdev-properties.h" 33 #include "hw/virtio/virtio-access.h" 34 #include "sysemu/dma.h" 35 #include "sysemu/runstate.h" 36 #include "standard-headers/linux/virtio_ids.h" 37 38 /* QAPI list of realized VirtIODevices */ 39 static QTAILQ_HEAD(, VirtIODevice) virtio_list; 40 41 /* 42 * The alignment to use between consumer and producer parts of vring. 43 * x86 pagesize again. This is the default, used by transports like PCI 44 * which don't provide a means for the guest to tell the host the alignment. 45 */ 46 #define VIRTIO_PCI_VRING_ALIGN 4096 47 48 typedef struct VRingDesc 49 { 50 uint64_t addr; 51 uint32_t len; 52 uint16_t flags; 53 uint16_t next; 54 } VRingDesc; 55 56 typedef struct VRingPackedDesc { 57 uint64_t addr; 58 uint32_t len; 59 uint16_t id; 60 uint16_t flags; 61 } VRingPackedDesc; 62 63 typedef struct VRingAvail 64 { 65 uint16_t flags; 66 uint16_t idx; 67 uint16_t ring[]; 68 } VRingAvail; 69 70 typedef struct VRingUsedElem 71 { 72 uint32_t id; 73 uint32_t len; 74 } VRingUsedElem; 75 76 typedef struct VRingUsed 77 { 78 uint16_t flags; 79 uint16_t idx; 80 VRingUsedElem ring[]; 81 } VRingUsed; 82 83 typedef struct VRingMemoryRegionCaches { 84 struct rcu_head rcu; 85 MemoryRegionCache desc; 86 MemoryRegionCache avail; 87 MemoryRegionCache used; 88 } VRingMemoryRegionCaches; 89 90 typedef struct VRing 91 { 92 unsigned int num; 93 unsigned int num_default; 94 unsigned int align; 95 hwaddr desc; 96 hwaddr avail; 97 hwaddr used; 98 VRingMemoryRegionCaches *caches; 99 } VRing; 100 101 typedef struct VRingPackedDescEvent { 102 uint16_t off_wrap; 103 uint16_t flags; 104 } VRingPackedDescEvent ; 105 106 struct VirtQueue 107 { 108 VRing vring; 109 VirtQueueElement *used_elems; 110 111 /* Next head to pop */ 112 uint16_t last_avail_idx; 113 bool last_avail_wrap_counter; 114 115 /* Last avail_idx read from VQ. */ 116 uint16_t shadow_avail_idx; 117 bool shadow_avail_wrap_counter; 118 119 uint16_t used_idx; 120 bool used_wrap_counter; 121 122 /* Last used index value we have signalled on */ 123 uint16_t signalled_used; 124 125 /* Last used index value we have signalled on */ 126 bool signalled_used_valid; 127 128 /* Notification enabled? */ 129 bool notification; 130 131 uint16_t queue_index; 132 133 unsigned int inuse; 134 135 uint16_t vector; 136 VirtIOHandleOutput handle_output; 137 VirtIODevice *vdev; 138 EventNotifier guest_notifier; 139 EventNotifier host_notifier; 140 bool host_notifier_enabled; 141 QLIST_ENTRY(VirtQueue) node; 142 }; 143 144 const char *virtio_device_names[] = { 145 [VIRTIO_ID_NET] = "virtio-net", 146 [VIRTIO_ID_BLOCK] = "virtio-blk", 147 [VIRTIO_ID_CONSOLE] = "virtio-serial", 148 [VIRTIO_ID_RNG] = "virtio-rng", 149 [VIRTIO_ID_BALLOON] = "virtio-balloon", 150 [VIRTIO_ID_IOMEM] = "virtio-iomem", 151 [VIRTIO_ID_RPMSG] = "virtio-rpmsg", 152 [VIRTIO_ID_SCSI] = "virtio-scsi", 153 [VIRTIO_ID_9P] = "virtio-9p", 154 [VIRTIO_ID_MAC80211_WLAN] = "virtio-mac-wlan", 155 [VIRTIO_ID_RPROC_SERIAL] = "virtio-rproc-serial", 156 [VIRTIO_ID_CAIF] = "virtio-caif", 157 [VIRTIO_ID_MEMORY_BALLOON] = "virtio-mem-balloon", 158 [VIRTIO_ID_GPU] = "virtio-gpu", 159 [VIRTIO_ID_CLOCK] = "virtio-clk", 160 [VIRTIO_ID_INPUT] = "virtio-input", 161 [VIRTIO_ID_VSOCK] = "vhost-vsock", 162 [VIRTIO_ID_CRYPTO] = "virtio-crypto", 163 [VIRTIO_ID_SIGNAL_DIST] = "virtio-signal", 164 [VIRTIO_ID_PSTORE] = "virtio-pstore", 165 [VIRTIO_ID_IOMMU] = "virtio-iommu", 166 [VIRTIO_ID_MEM] = "virtio-mem", 167 [VIRTIO_ID_SOUND] = "virtio-sound", 168 [VIRTIO_ID_FS] = "virtio-user-fs", 169 [VIRTIO_ID_PMEM] = "virtio-pmem", 170 [VIRTIO_ID_RPMB] = "virtio-rpmb", 171 [VIRTIO_ID_MAC80211_HWSIM] = "virtio-mac-hwsim", 172 [VIRTIO_ID_VIDEO_ENCODER] = "virtio-vid-encoder", 173 [VIRTIO_ID_VIDEO_DECODER] = "virtio-vid-decoder", 174 [VIRTIO_ID_SCMI] = "virtio-scmi", 175 [VIRTIO_ID_NITRO_SEC_MOD] = "virtio-nitro-sec-mod", 176 [VIRTIO_ID_I2C_ADAPTER] = "vhost-user-i2c", 177 [VIRTIO_ID_WATCHDOG] = "virtio-watchdog", 178 [VIRTIO_ID_CAN] = "virtio-can", 179 [VIRTIO_ID_DMABUF] = "virtio-dmabuf", 180 [VIRTIO_ID_PARAM_SERV] = "virtio-param-serv", 181 [VIRTIO_ID_AUDIO_POLICY] = "virtio-audio-pol", 182 [VIRTIO_ID_BT] = "virtio-bluetooth", 183 [VIRTIO_ID_GPIO] = "virtio-gpio" 184 }; 185 186 static const char *virtio_id_to_name(uint16_t device_id) 187 { 188 assert(device_id < G_N_ELEMENTS(virtio_device_names)); 189 const char *name = virtio_device_names[device_id]; 190 assert(name != NULL); 191 return name; 192 } 193 194 /* Called within call_rcu(). */ 195 static void virtio_free_region_cache(VRingMemoryRegionCaches *caches) 196 { 197 assert(caches != NULL); 198 address_space_cache_destroy(&caches->desc); 199 address_space_cache_destroy(&caches->avail); 200 address_space_cache_destroy(&caches->used); 201 g_free(caches); 202 } 203 204 static void virtio_virtqueue_reset_region_cache(struct VirtQueue *vq) 205 { 206 VRingMemoryRegionCaches *caches; 207 208 caches = qatomic_read(&vq->vring.caches); 209 qatomic_rcu_set(&vq->vring.caches, NULL); 210 if (caches) { 211 call_rcu(caches, virtio_free_region_cache, rcu); 212 } 213 } 214 215 static void virtio_init_region_cache(VirtIODevice *vdev, int n) 216 { 217 VirtQueue *vq = &vdev->vq[n]; 218 VRingMemoryRegionCaches *old = vq->vring.caches; 219 VRingMemoryRegionCaches *new = NULL; 220 hwaddr addr, size; 221 int64_t len; 222 bool packed; 223 224 225 addr = vq->vring.desc; 226 if (!addr) { 227 goto out_no_cache; 228 } 229 new = g_new0(VRingMemoryRegionCaches, 1); 230 size = virtio_queue_get_desc_size(vdev, n); 231 packed = virtio_vdev_has_feature(vq->vdev, VIRTIO_F_RING_PACKED) ? 232 true : false; 233 len = address_space_cache_init(&new->desc, vdev->dma_as, 234 addr, size, packed); 235 if (len < size) { 236 virtio_error(vdev, "Cannot map desc"); 237 goto err_desc; 238 } 239 240 size = virtio_queue_get_used_size(vdev, n); 241 len = address_space_cache_init(&new->used, vdev->dma_as, 242 vq->vring.used, size, true); 243 if (len < size) { 244 virtio_error(vdev, "Cannot map used"); 245 goto err_used; 246 } 247 248 size = virtio_queue_get_avail_size(vdev, n); 249 len = address_space_cache_init(&new->avail, vdev->dma_as, 250 vq->vring.avail, size, false); 251 if (len < size) { 252 virtio_error(vdev, "Cannot map avail"); 253 goto err_avail; 254 } 255 256 qatomic_rcu_set(&vq->vring.caches, new); 257 if (old) { 258 call_rcu(old, virtio_free_region_cache, rcu); 259 } 260 return; 261 262 err_avail: 263 address_space_cache_destroy(&new->avail); 264 err_used: 265 address_space_cache_destroy(&new->used); 266 err_desc: 267 address_space_cache_destroy(&new->desc); 268 out_no_cache: 269 g_free(new); 270 virtio_virtqueue_reset_region_cache(vq); 271 } 272 273 /* virt queue functions */ 274 void virtio_queue_update_rings(VirtIODevice *vdev, int n) 275 { 276 VRing *vring = &vdev->vq[n].vring; 277 278 if (!vring->num || !vring->desc || !vring->align) { 279 /* not yet setup -> nothing to do */ 280 return; 281 } 282 vring->avail = vring->desc + vring->num * sizeof(VRingDesc); 283 vring->used = vring_align(vring->avail + 284 offsetof(VRingAvail, ring[vring->num]), 285 vring->align); 286 virtio_init_region_cache(vdev, n); 287 } 288 289 /* Called within rcu_read_lock(). */ 290 static void vring_split_desc_read(VirtIODevice *vdev, VRingDesc *desc, 291 MemoryRegionCache *cache, int i) 292 { 293 address_space_read_cached(cache, i * sizeof(VRingDesc), 294 desc, sizeof(VRingDesc)); 295 virtio_tswap64s(vdev, &desc->addr); 296 virtio_tswap32s(vdev, &desc->len); 297 virtio_tswap16s(vdev, &desc->flags); 298 virtio_tswap16s(vdev, &desc->next); 299 } 300 301 static void vring_packed_event_read(VirtIODevice *vdev, 302 MemoryRegionCache *cache, 303 VRingPackedDescEvent *e) 304 { 305 hwaddr off_off = offsetof(VRingPackedDescEvent, off_wrap); 306 hwaddr off_flags = offsetof(VRingPackedDescEvent, flags); 307 308 e->flags = virtio_lduw_phys_cached(vdev, cache, off_flags); 309 /* Make sure flags is seen before off_wrap */ 310 smp_rmb(); 311 e->off_wrap = virtio_lduw_phys_cached(vdev, cache, off_off); 312 virtio_tswap16s(vdev, &e->flags); 313 } 314 315 static void vring_packed_off_wrap_write(VirtIODevice *vdev, 316 MemoryRegionCache *cache, 317 uint16_t off_wrap) 318 { 319 hwaddr off = offsetof(VRingPackedDescEvent, off_wrap); 320 321 virtio_stw_phys_cached(vdev, cache, off, off_wrap); 322 address_space_cache_invalidate(cache, off, sizeof(off_wrap)); 323 } 324 325 static void vring_packed_flags_write(VirtIODevice *vdev, 326 MemoryRegionCache *cache, uint16_t flags) 327 { 328 hwaddr off = offsetof(VRingPackedDescEvent, flags); 329 330 virtio_stw_phys_cached(vdev, cache, off, flags); 331 address_space_cache_invalidate(cache, off, sizeof(flags)); 332 } 333 334 /* Called within rcu_read_lock(). */ 335 static VRingMemoryRegionCaches *vring_get_region_caches(struct VirtQueue *vq) 336 { 337 return qatomic_rcu_read(&vq->vring.caches); 338 } 339 340 /* Called within rcu_read_lock(). */ 341 static inline uint16_t vring_avail_flags(VirtQueue *vq) 342 { 343 VRingMemoryRegionCaches *caches = vring_get_region_caches(vq); 344 hwaddr pa = offsetof(VRingAvail, flags); 345 346 if (!caches) { 347 return 0; 348 } 349 350 return virtio_lduw_phys_cached(vq->vdev, &caches->avail, pa); 351 } 352 353 /* Called within rcu_read_lock(). */ 354 static inline uint16_t vring_avail_idx(VirtQueue *vq) 355 { 356 VRingMemoryRegionCaches *caches = vring_get_region_caches(vq); 357 hwaddr pa = offsetof(VRingAvail, idx); 358 359 if (!caches) { 360 return 0; 361 } 362 363 vq->shadow_avail_idx = virtio_lduw_phys_cached(vq->vdev, &caches->avail, pa); 364 return vq->shadow_avail_idx; 365 } 366 367 /* Called within rcu_read_lock(). */ 368 static inline uint16_t vring_avail_ring(VirtQueue *vq, int i) 369 { 370 VRingMemoryRegionCaches *caches = vring_get_region_caches(vq); 371 hwaddr pa = offsetof(VRingAvail, ring[i]); 372 373 if (!caches) { 374 return 0; 375 } 376 377 return virtio_lduw_phys_cached(vq->vdev, &caches->avail, pa); 378 } 379 380 /* Called within rcu_read_lock(). */ 381 static inline uint16_t vring_get_used_event(VirtQueue *vq) 382 { 383 return vring_avail_ring(vq, vq->vring.num); 384 } 385 386 /* Called within rcu_read_lock(). */ 387 static inline void vring_used_write(VirtQueue *vq, VRingUsedElem *uelem, 388 int i) 389 { 390 VRingMemoryRegionCaches *caches = vring_get_region_caches(vq); 391 hwaddr pa = offsetof(VRingUsed, ring[i]); 392 393 if (!caches) { 394 return; 395 } 396 397 virtio_tswap32s(vq->vdev, &uelem->id); 398 virtio_tswap32s(vq->vdev, &uelem->len); 399 address_space_write_cached(&caches->used, pa, uelem, sizeof(VRingUsedElem)); 400 address_space_cache_invalidate(&caches->used, pa, sizeof(VRingUsedElem)); 401 } 402 403 /* Called within rcu_read_lock(). */ 404 static uint16_t vring_used_idx(VirtQueue *vq) 405 { 406 VRingMemoryRegionCaches *caches = vring_get_region_caches(vq); 407 hwaddr pa = offsetof(VRingUsed, idx); 408 409 if (!caches) { 410 return 0; 411 } 412 413 return virtio_lduw_phys_cached(vq->vdev, &caches->used, pa); 414 } 415 416 /* Called within rcu_read_lock(). */ 417 static inline void vring_used_idx_set(VirtQueue *vq, uint16_t val) 418 { 419 VRingMemoryRegionCaches *caches = vring_get_region_caches(vq); 420 hwaddr pa = offsetof(VRingUsed, idx); 421 422 if (caches) { 423 virtio_stw_phys_cached(vq->vdev, &caches->used, pa, val); 424 address_space_cache_invalidate(&caches->used, pa, sizeof(val)); 425 } 426 427 vq->used_idx = val; 428 } 429 430 /* Called within rcu_read_lock(). */ 431 static inline void vring_used_flags_set_bit(VirtQueue *vq, int mask) 432 { 433 VRingMemoryRegionCaches *caches = vring_get_region_caches(vq); 434 VirtIODevice *vdev = vq->vdev; 435 hwaddr pa = offsetof(VRingUsed, flags); 436 uint16_t flags; 437 438 if (!caches) { 439 return; 440 } 441 442 flags = virtio_lduw_phys_cached(vq->vdev, &caches->used, pa); 443 virtio_stw_phys_cached(vdev, &caches->used, pa, flags | mask); 444 address_space_cache_invalidate(&caches->used, pa, sizeof(flags)); 445 } 446 447 /* Called within rcu_read_lock(). */ 448 static inline void vring_used_flags_unset_bit(VirtQueue *vq, int mask) 449 { 450 VRingMemoryRegionCaches *caches = vring_get_region_caches(vq); 451 VirtIODevice *vdev = vq->vdev; 452 hwaddr pa = offsetof(VRingUsed, flags); 453 uint16_t flags; 454 455 if (!caches) { 456 return; 457 } 458 459 flags = virtio_lduw_phys_cached(vq->vdev, &caches->used, pa); 460 virtio_stw_phys_cached(vdev, &caches->used, pa, flags & ~mask); 461 address_space_cache_invalidate(&caches->used, pa, sizeof(flags)); 462 } 463 464 /* Called within rcu_read_lock(). */ 465 static inline void vring_set_avail_event(VirtQueue *vq, uint16_t val) 466 { 467 VRingMemoryRegionCaches *caches; 468 hwaddr pa; 469 if (!vq->notification) { 470 return; 471 } 472 473 caches = vring_get_region_caches(vq); 474 if (!caches) { 475 return; 476 } 477 478 pa = offsetof(VRingUsed, ring[vq->vring.num]); 479 virtio_stw_phys_cached(vq->vdev, &caches->used, pa, val); 480 address_space_cache_invalidate(&caches->used, pa, sizeof(val)); 481 } 482 483 static void virtio_queue_split_set_notification(VirtQueue *vq, int enable) 484 { 485 RCU_READ_LOCK_GUARD(); 486 487 if (virtio_vdev_has_feature(vq->vdev, VIRTIO_RING_F_EVENT_IDX)) { 488 vring_set_avail_event(vq, vring_avail_idx(vq)); 489 } else if (enable) { 490 vring_used_flags_unset_bit(vq, VRING_USED_F_NO_NOTIFY); 491 } else { 492 vring_used_flags_set_bit(vq, VRING_USED_F_NO_NOTIFY); 493 } 494 if (enable) { 495 /* Expose avail event/used flags before caller checks the avail idx. */ 496 smp_mb(); 497 } 498 } 499 500 static void virtio_queue_packed_set_notification(VirtQueue *vq, int enable) 501 { 502 uint16_t off_wrap; 503 VRingPackedDescEvent e; 504 VRingMemoryRegionCaches *caches; 505 506 RCU_READ_LOCK_GUARD(); 507 caches = vring_get_region_caches(vq); 508 if (!caches) { 509 return; 510 } 511 512 vring_packed_event_read(vq->vdev, &caches->used, &e); 513 514 if (!enable) { 515 e.flags = VRING_PACKED_EVENT_FLAG_DISABLE; 516 } else if (virtio_vdev_has_feature(vq->vdev, VIRTIO_RING_F_EVENT_IDX)) { 517 off_wrap = vq->shadow_avail_idx | vq->shadow_avail_wrap_counter << 15; 518 vring_packed_off_wrap_write(vq->vdev, &caches->used, off_wrap); 519 /* Make sure off_wrap is wrote before flags */ 520 smp_wmb(); 521 e.flags = VRING_PACKED_EVENT_FLAG_DESC; 522 } else { 523 e.flags = VRING_PACKED_EVENT_FLAG_ENABLE; 524 } 525 526 vring_packed_flags_write(vq->vdev, &caches->used, e.flags); 527 if (enable) { 528 /* Expose avail event/used flags before caller checks the avail idx. */ 529 smp_mb(); 530 } 531 } 532 533 bool virtio_queue_get_notification(VirtQueue *vq) 534 { 535 return vq->notification; 536 } 537 538 void virtio_queue_set_notification(VirtQueue *vq, int enable) 539 { 540 vq->notification = enable; 541 542 if (!vq->vring.desc) { 543 return; 544 } 545 546 if (virtio_vdev_has_feature(vq->vdev, VIRTIO_F_RING_PACKED)) { 547 virtio_queue_packed_set_notification(vq, enable); 548 } else { 549 virtio_queue_split_set_notification(vq, enable); 550 } 551 } 552 553 int virtio_queue_ready(VirtQueue *vq) 554 { 555 return vq->vring.avail != 0; 556 } 557 558 static void vring_packed_desc_read_flags(VirtIODevice *vdev, 559 uint16_t *flags, 560 MemoryRegionCache *cache, 561 int i) 562 { 563 hwaddr off = i * sizeof(VRingPackedDesc) + offsetof(VRingPackedDesc, flags); 564 565 *flags = virtio_lduw_phys_cached(vdev, cache, off); 566 } 567 568 static void vring_packed_desc_read(VirtIODevice *vdev, 569 VRingPackedDesc *desc, 570 MemoryRegionCache *cache, 571 int i, bool strict_order) 572 { 573 hwaddr off = i * sizeof(VRingPackedDesc); 574 575 vring_packed_desc_read_flags(vdev, &desc->flags, cache, i); 576 577 if (strict_order) { 578 /* Make sure flags is read before the rest fields. */ 579 smp_rmb(); 580 } 581 582 address_space_read_cached(cache, off + offsetof(VRingPackedDesc, addr), 583 &desc->addr, sizeof(desc->addr)); 584 address_space_read_cached(cache, off + offsetof(VRingPackedDesc, id), 585 &desc->id, sizeof(desc->id)); 586 address_space_read_cached(cache, off + offsetof(VRingPackedDesc, len), 587 &desc->len, sizeof(desc->len)); 588 virtio_tswap64s(vdev, &desc->addr); 589 virtio_tswap16s(vdev, &desc->id); 590 virtio_tswap32s(vdev, &desc->len); 591 } 592 593 static void vring_packed_desc_write_data(VirtIODevice *vdev, 594 VRingPackedDesc *desc, 595 MemoryRegionCache *cache, 596 int i) 597 { 598 hwaddr off_id = i * sizeof(VRingPackedDesc) + 599 offsetof(VRingPackedDesc, id); 600 hwaddr off_len = i * sizeof(VRingPackedDesc) + 601 offsetof(VRingPackedDesc, len); 602 603 virtio_tswap32s(vdev, &desc->len); 604 virtio_tswap16s(vdev, &desc->id); 605 address_space_write_cached(cache, off_id, &desc->id, sizeof(desc->id)); 606 address_space_cache_invalidate(cache, off_id, sizeof(desc->id)); 607 address_space_write_cached(cache, off_len, &desc->len, sizeof(desc->len)); 608 address_space_cache_invalidate(cache, off_len, sizeof(desc->len)); 609 } 610 611 static void vring_packed_desc_write_flags(VirtIODevice *vdev, 612 VRingPackedDesc *desc, 613 MemoryRegionCache *cache, 614 int i) 615 { 616 hwaddr off = i * sizeof(VRingPackedDesc) + offsetof(VRingPackedDesc, flags); 617 618 virtio_stw_phys_cached(vdev, cache, off, desc->flags); 619 address_space_cache_invalidate(cache, off, sizeof(desc->flags)); 620 } 621 622 static void vring_packed_desc_write(VirtIODevice *vdev, 623 VRingPackedDesc *desc, 624 MemoryRegionCache *cache, 625 int i, bool strict_order) 626 { 627 vring_packed_desc_write_data(vdev, desc, cache, i); 628 if (strict_order) { 629 /* Make sure data is wrote before flags. */ 630 smp_wmb(); 631 } 632 vring_packed_desc_write_flags(vdev, desc, cache, i); 633 } 634 635 static inline bool is_desc_avail(uint16_t flags, bool wrap_counter) 636 { 637 bool avail, used; 638 639 avail = !!(flags & (1 << VRING_PACKED_DESC_F_AVAIL)); 640 used = !!(flags & (1 << VRING_PACKED_DESC_F_USED)); 641 return (avail != used) && (avail == wrap_counter); 642 } 643 644 /* Fetch avail_idx from VQ memory only when we really need to know if 645 * guest has added some buffers. 646 * Called within rcu_read_lock(). */ 647 static int virtio_queue_empty_rcu(VirtQueue *vq) 648 { 649 if (virtio_device_disabled(vq->vdev)) { 650 return 1; 651 } 652 653 if (unlikely(!vq->vring.avail)) { 654 return 1; 655 } 656 657 if (vq->shadow_avail_idx != vq->last_avail_idx) { 658 return 0; 659 } 660 661 return vring_avail_idx(vq) == vq->last_avail_idx; 662 } 663 664 static int virtio_queue_split_empty(VirtQueue *vq) 665 { 666 bool empty; 667 668 if (virtio_device_disabled(vq->vdev)) { 669 return 1; 670 } 671 672 if (unlikely(!vq->vring.avail)) { 673 return 1; 674 } 675 676 if (vq->shadow_avail_idx != vq->last_avail_idx) { 677 return 0; 678 } 679 680 RCU_READ_LOCK_GUARD(); 681 empty = vring_avail_idx(vq) == vq->last_avail_idx; 682 return empty; 683 } 684 685 /* Called within rcu_read_lock(). */ 686 static int virtio_queue_packed_empty_rcu(VirtQueue *vq) 687 { 688 struct VRingPackedDesc desc; 689 VRingMemoryRegionCaches *cache; 690 691 if (unlikely(!vq->vring.desc)) { 692 return 1; 693 } 694 695 cache = vring_get_region_caches(vq); 696 if (!cache) { 697 return 1; 698 } 699 700 vring_packed_desc_read_flags(vq->vdev, &desc.flags, &cache->desc, 701 vq->last_avail_idx); 702 703 return !is_desc_avail(desc.flags, vq->last_avail_wrap_counter); 704 } 705 706 static int virtio_queue_packed_empty(VirtQueue *vq) 707 { 708 RCU_READ_LOCK_GUARD(); 709 return virtio_queue_packed_empty_rcu(vq); 710 } 711 712 int virtio_queue_empty(VirtQueue *vq) 713 { 714 if (virtio_vdev_has_feature(vq->vdev, VIRTIO_F_RING_PACKED)) { 715 return virtio_queue_packed_empty(vq); 716 } else { 717 return virtio_queue_split_empty(vq); 718 } 719 } 720 721 static void virtqueue_unmap_sg(VirtQueue *vq, const VirtQueueElement *elem, 722 unsigned int len) 723 { 724 AddressSpace *dma_as = vq->vdev->dma_as; 725 unsigned int offset; 726 int i; 727 728 offset = 0; 729 for (i = 0; i < elem->in_num; i++) { 730 size_t size = MIN(len - offset, elem->in_sg[i].iov_len); 731 732 dma_memory_unmap(dma_as, elem->in_sg[i].iov_base, 733 elem->in_sg[i].iov_len, 734 DMA_DIRECTION_FROM_DEVICE, size); 735 736 offset += size; 737 } 738 739 for (i = 0; i < elem->out_num; i++) 740 dma_memory_unmap(dma_as, elem->out_sg[i].iov_base, 741 elem->out_sg[i].iov_len, 742 DMA_DIRECTION_TO_DEVICE, 743 elem->out_sg[i].iov_len); 744 } 745 746 /* virtqueue_detach_element: 747 * @vq: The #VirtQueue 748 * @elem: The #VirtQueueElement 749 * @len: number of bytes written 750 * 751 * Detach the element from the virtqueue. This function is suitable for device 752 * reset or other situations where a #VirtQueueElement is simply freed and will 753 * not be pushed or discarded. 754 */ 755 void virtqueue_detach_element(VirtQueue *vq, const VirtQueueElement *elem, 756 unsigned int len) 757 { 758 vq->inuse -= elem->ndescs; 759 virtqueue_unmap_sg(vq, elem, len); 760 } 761 762 static void virtqueue_split_rewind(VirtQueue *vq, unsigned int num) 763 { 764 vq->last_avail_idx -= num; 765 } 766 767 static void virtqueue_packed_rewind(VirtQueue *vq, unsigned int num) 768 { 769 if (vq->last_avail_idx < num) { 770 vq->last_avail_idx = vq->vring.num + vq->last_avail_idx - num; 771 vq->last_avail_wrap_counter ^= 1; 772 } else { 773 vq->last_avail_idx -= num; 774 } 775 } 776 777 /* virtqueue_unpop: 778 * @vq: The #VirtQueue 779 * @elem: The #VirtQueueElement 780 * @len: number of bytes written 781 * 782 * Pretend the most recent element wasn't popped from the virtqueue. The next 783 * call to virtqueue_pop() will refetch the element. 784 */ 785 void virtqueue_unpop(VirtQueue *vq, const VirtQueueElement *elem, 786 unsigned int len) 787 { 788 789 if (virtio_vdev_has_feature(vq->vdev, VIRTIO_F_RING_PACKED)) { 790 virtqueue_packed_rewind(vq, 1); 791 } else { 792 virtqueue_split_rewind(vq, 1); 793 } 794 795 virtqueue_detach_element(vq, elem, len); 796 } 797 798 /* virtqueue_rewind: 799 * @vq: The #VirtQueue 800 * @num: Number of elements to push back 801 * 802 * Pretend that elements weren't popped from the virtqueue. The next 803 * virtqueue_pop() will refetch the oldest element. 804 * 805 * Use virtqueue_unpop() instead if you have a VirtQueueElement. 806 * 807 * Returns: true on success, false if @num is greater than the number of in use 808 * elements. 809 */ 810 bool virtqueue_rewind(VirtQueue *vq, unsigned int num) 811 { 812 if (num > vq->inuse) { 813 return false; 814 } 815 816 vq->inuse -= num; 817 if (virtio_vdev_has_feature(vq->vdev, VIRTIO_F_RING_PACKED)) { 818 virtqueue_packed_rewind(vq, num); 819 } else { 820 virtqueue_split_rewind(vq, num); 821 } 822 return true; 823 } 824 825 static void virtqueue_split_fill(VirtQueue *vq, const VirtQueueElement *elem, 826 unsigned int len, unsigned int idx) 827 { 828 VRingUsedElem uelem; 829 830 if (unlikely(!vq->vring.used)) { 831 return; 832 } 833 834 idx = (idx + vq->used_idx) % vq->vring.num; 835 836 uelem.id = elem->index; 837 uelem.len = len; 838 vring_used_write(vq, &uelem, idx); 839 } 840 841 static void virtqueue_packed_fill(VirtQueue *vq, const VirtQueueElement *elem, 842 unsigned int len, unsigned int idx) 843 { 844 vq->used_elems[idx].index = elem->index; 845 vq->used_elems[idx].len = len; 846 vq->used_elems[idx].ndescs = elem->ndescs; 847 } 848 849 static void virtqueue_packed_fill_desc(VirtQueue *vq, 850 const VirtQueueElement *elem, 851 unsigned int idx, 852 bool strict_order) 853 { 854 uint16_t head; 855 VRingMemoryRegionCaches *caches; 856 VRingPackedDesc desc = { 857 .id = elem->index, 858 .len = elem->len, 859 }; 860 bool wrap_counter = vq->used_wrap_counter; 861 862 if (unlikely(!vq->vring.desc)) { 863 return; 864 } 865 866 head = vq->used_idx + idx; 867 if (head >= vq->vring.num) { 868 head -= vq->vring.num; 869 wrap_counter ^= 1; 870 } 871 if (wrap_counter) { 872 desc.flags |= (1 << VRING_PACKED_DESC_F_AVAIL); 873 desc.flags |= (1 << VRING_PACKED_DESC_F_USED); 874 } else { 875 desc.flags &= ~(1 << VRING_PACKED_DESC_F_AVAIL); 876 desc.flags &= ~(1 << VRING_PACKED_DESC_F_USED); 877 } 878 879 caches = vring_get_region_caches(vq); 880 if (!caches) { 881 return; 882 } 883 884 vring_packed_desc_write(vq->vdev, &desc, &caches->desc, head, strict_order); 885 } 886 887 /* Called within rcu_read_lock(). */ 888 void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem, 889 unsigned int len, unsigned int idx) 890 { 891 trace_virtqueue_fill(vq, elem, len, idx); 892 893 virtqueue_unmap_sg(vq, elem, len); 894 895 if (virtio_device_disabled(vq->vdev)) { 896 return; 897 } 898 899 if (virtio_vdev_has_feature(vq->vdev, VIRTIO_F_RING_PACKED)) { 900 virtqueue_packed_fill(vq, elem, len, idx); 901 } else { 902 virtqueue_split_fill(vq, elem, len, idx); 903 } 904 } 905 906 /* Called within rcu_read_lock(). */ 907 static void virtqueue_split_flush(VirtQueue *vq, unsigned int count) 908 { 909 uint16_t old, new; 910 911 if (unlikely(!vq->vring.used)) { 912 return; 913 } 914 915 /* Make sure buffer is written before we update index. */ 916 smp_wmb(); 917 trace_virtqueue_flush(vq, count); 918 old = vq->used_idx; 919 new = old + count; 920 vring_used_idx_set(vq, new); 921 vq->inuse -= count; 922 if (unlikely((int16_t)(new - vq->signalled_used) < (uint16_t)(new - old))) 923 vq->signalled_used_valid = false; 924 } 925 926 static void virtqueue_packed_flush(VirtQueue *vq, unsigned int count) 927 { 928 unsigned int i, ndescs = 0; 929 930 if (unlikely(!vq->vring.desc)) { 931 return; 932 } 933 934 for (i = 1; i < count; i++) { 935 virtqueue_packed_fill_desc(vq, &vq->used_elems[i], i, false); 936 ndescs += vq->used_elems[i].ndescs; 937 } 938 virtqueue_packed_fill_desc(vq, &vq->used_elems[0], 0, true); 939 ndescs += vq->used_elems[0].ndescs; 940 941 vq->inuse -= ndescs; 942 vq->used_idx += ndescs; 943 if (vq->used_idx >= vq->vring.num) { 944 vq->used_idx -= vq->vring.num; 945 vq->used_wrap_counter ^= 1; 946 vq->signalled_used_valid = false; 947 } 948 } 949 950 void virtqueue_flush(VirtQueue *vq, unsigned int count) 951 { 952 if (virtio_device_disabled(vq->vdev)) { 953 vq->inuse -= count; 954 return; 955 } 956 957 if (virtio_vdev_has_feature(vq->vdev, VIRTIO_F_RING_PACKED)) { 958 virtqueue_packed_flush(vq, count); 959 } else { 960 virtqueue_split_flush(vq, count); 961 } 962 } 963 964 void virtqueue_push(VirtQueue *vq, const VirtQueueElement *elem, 965 unsigned int len) 966 { 967 RCU_READ_LOCK_GUARD(); 968 virtqueue_fill(vq, elem, len, 0); 969 virtqueue_flush(vq, 1); 970 } 971 972 /* Called within rcu_read_lock(). */ 973 static int virtqueue_num_heads(VirtQueue *vq, unsigned int idx) 974 { 975 uint16_t num_heads = vring_avail_idx(vq) - idx; 976 977 /* Check it isn't doing very strange things with descriptor numbers. */ 978 if (num_heads > vq->vring.num) { 979 virtio_error(vq->vdev, "Guest moved used index from %u to %u", 980 idx, vq->shadow_avail_idx); 981 return -EINVAL; 982 } 983 /* On success, callers read a descriptor at vq->last_avail_idx. 984 * Make sure descriptor read does not bypass avail index read. */ 985 if (num_heads) { 986 smp_rmb(); 987 } 988 989 return num_heads; 990 } 991 992 /* Called within rcu_read_lock(). */ 993 static bool virtqueue_get_head(VirtQueue *vq, unsigned int idx, 994 unsigned int *head) 995 { 996 /* Grab the next descriptor number they're advertising, and increment 997 * the index we've seen. */ 998 *head = vring_avail_ring(vq, idx % vq->vring.num); 999 1000 /* If their number is silly, that's a fatal mistake. */ 1001 if (*head >= vq->vring.num) { 1002 virtio_error(vq->vdev, "Guest says index %u is available", *head); 1003 return false; 1004 } 1005 1006 return true; 1007 } 1008 1009 enum { 1010 VIRTQUEUE_READ_DESC_ERROR = -1, 1011 VIRTQUEUE_READ_DESC_DONE = 0, /* end of chain */ 1012 VIRTQUEUE_READ_DESC_MORE = 1, /* more buffers in chain */ 1013 }; 1014 1015 static int virtqueue_split_read_next_desc(VirtIODevice *vdev, VRingDesc *desc, 1016 MemoryRegionCache *desc_cache, 1017 unsigned int max, unsigned int *next) 1018 { 1019 /* If this descriptor says it doesn't chain, we're done. */ 1020 if (!(desc->flags & VRING_DESC_F_NEXT)) { 1021 return VIRTQUEUE_READ_DESC_DONE; 1022 } 1023 1024 /* Check they're not leading us off end of descriptors. */ 1025 *next = desc->next; 1026 /* Make sure compiler knows to grab that: we don't want it changing! */ 1027 smp_wmb(); 1028 1029 if (*next >= max) { 1030 virtio_error(vdev, "Desc next is %u", *next); 1031 return VIRTQUEUE_READ_DESC_ERROR; 1032 } 1033 1034 vring_split_desc_read(vdev, desc, desc_cache, *next); 1035 return VIRTQUEUE_READ_DESC_MORE; 1036 } 1037 1038 /* Called within rcu_read_lock(). */ 1039 static void virtqueue_split_get_avail_bytes(VirtQueue *vq, 1040 unsigned int *in_bytes, unsigned int *out_bytes, 1041 unsigned max_in_bytes, unsigned max_out_bytes, 1042 VRingMemoryRegionCaches *caches) 1043 { 1044 VirtIODevice *vdev = vq->vdev; 1045 unsigned int max, idx; 1046 unsigned int total_bufs, in_total, out_total; 1047 MemoryRegionCache indirect_desc_cache = MEMORY_REGION_CACHE_INVALID; 1048 int64_t len = 0; 1049 int rc; 1050 1051 idx = vq->last_avail_idx; 1052 total_bufs = in_total = out_total = 0; 1053 1054 max = vq->vring.num; 1055 1056 while ((rc = virtqueue_num_heads(vq, idx)) > 0) { 1057 MemoryRegionCache *desc_cache = &caches->desc; 1058 unsigned int num_bufs; 1059 VRingDesc desc; 1060 unsigned int i; 1061 1062 num_bufs = total_bufs; 1063 1064 if (!virtqueue_get_head(vq, idx++, &i)) { 1065 goto err; 1066 } 1067 1068 vring_split_desc_read(vdev, &desc, desc_cache, i); 1069 1070 if (desc.flags & VRING_DESC_F_INDIRECT) { 1071 if (!desc.len || (desc.len % sizeof(VRingDesc))) { 1072 virtio_error(vdev, "Invalid size for indirect buffer table"); 1073 goto err; 1074 } 1075 1076 /* If we've got too many, that implies a descriptor loop. */ 1077 if (num_bufs >= max) { 1078 virtio_error(vdev, "Looped descriptor"); 1079 goto err; 1080 } 1081 1082 /* loop over the indirect descriptor table */ 1083 len = address_space_cache_init(&indirect_desc_cache, 1084 vdev->dma_as, 1085 desc.addr, desc.len, false); 1086 desc_cache = &indirect_desc_cache; 1087 if (len < desc.len) { 1088 virtio_error(vdev, "Cannot map indirect buffer"); 1089 goto err; 1090 } 1091 1092 max = desc.len / sizeof(VRingDesc); 1093 num_bufs = i = 0; 1094 vring_split_desc_read(vdev, &desc, desc_cache, i); 1095 } 1096 1097 do { 1098 /* If we've got too many, that implies a descriptor loop. */ 1099 if (++num_bufs > max) { 1100 virtio_error(vdev, "Looped descriptor"); 1101 goto err; 1102 } 1103 1104 if (desc.flags & VRING_DESC_F_WRITE) { 1105 in_total += desc.len; 1106 } else { 1107 out_total += desc.len; 1108 } 1109 if (in_total >= max_in_bytes && out_total >= max_out_bytes) { 1110 goto done; 1111 } 1112 1113 rc = virtqueue_split_read_next_desc(vdev, &desc, desc_cache, max, &i); 1114 } while (rc == VIRTQUEUE_READ_DESC_MORE); 1115 1116 if (rc == VIRTQUEUE_READ_DESC_ERROR) { 1117 goto err; 1118 } 1119 1120 if (desc_cache == &indirect_desc_cache) { 1121 address_space_cache_destroy(&indirect_desc_cache); 1122 total_bufs++; 1123 } else { 1124 total_bufs = num_bufs; 1125 } 1126 } 1127 1128 if (rc < 0) { 1129 goto err; 1130 } 1131 1132 done: 1133 address_space_cache_destroy(&indirect_desc_cache); 1134 if (in_bytes) { 1135 *in_bytes = in_total; 1136 } 1137 if (out_bytes) { 1138 *out_bytes = out_total; 1139 } 1140 return; 1141 1142 err: 1143 in_total = out_total = 0; 1144 goto done; 1145 } 1146 1147 static int virtqueue_packed_read_next_desc(VirtQueue *vq, 1148 VRingPackedDesc *desc, 1149 MemoryRegionCache 1150 *desc_cache, 1151 unsigned int max, 1152 unsigned int *next, 1153 bool indirect) 1154 { 1155 /* If this descriptor says it doesn't chain, we're done. */ 1156 if (!indirect && !(desc->flags & VRING_DESC_F_NEXT)) { 1157 return VIRTQUEUE_READ_DESC_DONE; 1158 } 1159 1160 ++*next; 1161 if (*next == max) { 1162 if (indirect) { 1163 return VIRTQUEUE_READ_DESC_DONE; 1164 } else { 1165 (*next) -= vq->vring.num; 1166 } 1167 } 1168 1169 vring_packed_desc_read(vq->vdev, desc, desc_cache, *next, false); 1170 return VIRTQUEUE_READ_DESC_MORE; 1171 } 1172 1173 /* Called within rcu_read_lock(). */ 1174 static void virtqueue_packed_get_avail_bytes(VirtQueue *vq, 1175 unsigned int *in_bytes, 1176 unsigned int *out_bytes, 1177 unsigned max_in_bytes, 1178 unsigned max_out_bytes, 1179 VRingMemoryRegionCaches *caches) 1180 { 1181 VirtIODevice *vdev = vq->vdev; 1182 unsigned int max, idx; 1183 unsigned int total_bufs, in_total, out_total; 1184 MemoryRegionCache *desc_cache; 1185 MemoryRegionCache indirect_desc_cache = MEMORY_REGION_CACHE_INVALID; 1186 int64_t len = 0; 1187 VRingPackedDesc desc; 1188 bool wrap_counter; 1189 1190 idx = vq->last_avail_idx; 1191 wrap_counter = vq->last_avail_wrap_counter; 1192 total_bufs = in_total = out_total = 0; 1193 1194 max = vq->vring.num; 1195 1196 for (;;) { 1197 unsigned int num_bufs = total_bufs; 1198 unsigned int i = idx; 1199 int rc; 1200 1201 desc_cache = &caches->desc; 1202 vring_packed_desc_read(vdev, &desc, desc_cache, idx, true); 1203 if (!is_desc_avail(desc.flags, wrap_counter)) { 1204 break; 1205 } 1206 1207 if (desc.flags & VRING_DESC_F_INDIRECT) { 1208 if (desc.len % sizeof(VRingPackedDesc)) { 1209 virtio_error(vdev, "Invalid size for indirect buffer table"); 1210 goto err; 1211 } 1212 1213 /* If we've got too many, that implies a descriptor loop. */ 1214 if (num_bufs >= max) { 1215 virtio_error(vdev, "Looped descriptor"); 1216 goto err; 1217 } 1218 1219 /* loop over the indirect descriptor table */ 1220 len = address_space_cache_init(&indirect_desc_cache, 1221 vdev->dma_as, 1222 desc.addr, desc.len, false); 1223 desc_cache = &indirect_desc_cache; 1224 if (len < desc.len) { 1225 virtio_error(vdev, "Cannot map indirect buffer"); 1226 goto err; 1227 } 1228 1229 max = desc.len / sizeof(VRingPackedDesc); 1230 num_bufs = i = 0; 1231 vring_packed_desc_read(vdev, &desc, desc_cache, i, false); 1232 } 1233 1234 do { 1235 /* If we've got too many, that implies a descriptor loop. */ 1236 if (++num_bufs > max) { 1237 virtio_error(vdev, "Looped descriptor"); 1238 goto err; 1239 } 1240 1241 if (desc.flags & VRING_DESC_F_WRITE) { 1242 in_total += desc.len; 1243 } else { 1244 out_total += desc.len; 1245 } 1246 if (in_total >= max_in_bytes && out_total >= max_out_bytes) { 1247 goto done; 1248 } 1249 1250 rc = virtqueue_packed_read_next_desc(vq, &desc, desc_cache, max, 1251 &i, desc_cache == 1252 &indirect_desc_cache); 1253 } while (rc == VIRTQUEUE_READ_DESC_MORE); 1254 1255 if (desc_cache == &indirect_desc_cache) { 1256 address_space_cache_destroy(&indirect_desc_cache); 1257 total_bufs++; 1258 idx++; 1259 } else { 1260 idx += num_bufs - total_bufs; 1261 total_bufs = num_bufs; 1262 } 1263 1264 if (idx >= vq->vring.num) { 1265 idx -= vq->vring.num; 1266 wrap_counter ^= 1; 1267 } 1268 } 1269 1270 /* Record the index and wrap counter for a kick we want */ 1271 vq->shadow_avail_idx = idx; 1272 vq->shadow_avail_wrap_counter = wrap_counter; 1273 done: 1274 address_space_cache_destroy(&indirect_desc_cache); 1275 if (in_bytes) { 1276 *in_bytes = in_total; 1277 } 1278 if (out_bytes) { 1279 *out_bytes = out_total; 1280 } 1281 return; 1282 1283 err: 1284 in_total = out_total = 0; 1285 goto done; 1286 } 1287 1288 void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes, 1289 unsigned int *out_bytes, 1290 unsigned max_in_bytes, unsigned max_out_bytes) 1291 { 1292 uint16_t desc_size; 1293 VRingMemoryRegionCaches *caches; 1294 1295 RCU_READ_LOCK_GUARD(); 1296 1297 if (unlikely(!vq->vring.desc)) { 1298 goto err; 1299 } 1300 1301 caches = vring_get_region_caches(vq); 1302 if (!caches) { 1303 goto err; 1304 } 1305 1306 desc_size = virtio_vdev_has_feature(vq->vdev, VIRTIO_F_RING_PACKED) ? 1307 sizeof(VRingPackedDesc) : sizeof(VRingDesc); 1308 if (caches->desc.len < vq->vring.num * desc_size) { 1309 virtio_error(vq->vdev, "Cannot map descriptor ring"); 1310 goto err; 1311 } 1312 1313 if (virtio_vdev_has_feature(vq->vdev, VIRTIO_F_RING_PACKED)) { 1314 virtqueue_packed_get_avail_bytes(vq, in_bytes, out_bytes, 1315 max_in_bytes, max_out_bytes, 1316 caches); 1317 } else { 1318 virtqueue_split_get_avail_bytes(vq, in_bytes, out_bytes, 1319 max_in_bytes, max_out_bytes, 1320 caches); 1321 } 1322 1323 return; 1324 err: 1325 if (in_bytes) { 1326 *in_bytes = 0; 1327 } 1328 if (out_bytes) { 1329 *out_bytes = 0; 1330 } 1331 } 1332 1333 int virtqueue_avail_bytes(VirtQueue *vq, unsigned int in_bytes, 1334 unsigned int out_bytes) 1335 { 1336 unsigned int in_total, out_total; 1337 1338 virtqueue_get_avail_bytes(vq, &in_total, &out_total, in_bytes, out_bytes); 1339 return in_bytes <= in_total && out_bytes <= out_total; 1340 } 1341 1342 static bool virtqueue_map_desc(VirtIODevice *vdev, unsigned int *p_num_sg, 1343 hwaddr *addr, struct iovec *iov, 1344 unsigned int max_num_sg, bool is_write, 1345 hwaddr pa, size_t sz) 1346 { 1347 bool ok = false; 1348 unsigned num_sg = *p_num_sg; 1349 assert(num_sg <= max_num_sg); 1350 1351 if (!sz) { 1352 virtio_error(vdev, "virtio: zero sized buffers are not allowed"); 1353 goto out; 1354 } 1355 1356 while (sz) { 1357 hwaddr len = sz; 1358 1359 if (num_sg == max_num_sg) { 1360 virtio_error(vdev, "virtio: too many write descriptors in " 1361 "indirect table"); 1362 goto out; 1363 } 1364 1365 iov[num_sg].iov_base = dma_memory_map(vdev->dma_as, pa, &len, 1366 is_write ? 1367 DMA_DIRECTION_FROM_DEVICE : 1368 DMA_DIRECTION_TO_DEVICE, 1369 MEMTXATTRS_UNSPECIFIED); 1370 if (!iov[num_sg].iov_base) { 1371 virtio_error(vdev, "virtio: bogus descriptor or out of resources"); 1372 goto out; 1373 } 1374 1375 iov[num_sg].iov_len = len; 1376 addr[num_sg] = pa; 1377 1378 sz -= len; 1379 pa += len; 1380 num_sg++; 1381 } 1382 ok = true; 1383 1384 out: 1385 *p_num_sg = num_sg; 1386 return ok; 1387 } 1388 1389 /* Only used by error code paths before we have a VirtQueueElement (therefore 1390 * virtqueue_unmap_sg() can't be used). Assumes buffers weren't written to 1391 * yet. 1392 */ 1393 static void virtqueue_undo_map_desc(unsigned int out_num, unsigned int in_num, 1394 struct iovec *iov) 1395 { 1396 unsigned int i; 1397 1398 for (i = 0; i < out_num + in_num; i++) { 1399 int is_write = i >= out_num; 1400 1401 cpu_physical_memory_unmap(iov->iov_base, iov->iov_len, is_write, 0); 1402 iov++; 1403 } 1404 } 1405 1406 static void virtqueue_map_iovec(VirtIODevice *vdev, struct iovec *sg, 1407 hwaddr *addr, unsigned int num_sg, 1408 bool is_write) 1409 { 1410 unsigned int i; 1411 hwaddr len; 1412 1413 for (i = 0; i < num_sg; i++) { 1414 len = sg[i].iov_len; 1415 sg[i].iov_base = dma_memory_map(vdev->dma_as, 1416 addr[i], &len, is_write ? 1417 DMA_DIRECTION_FROM_DEVICE : 1418 DMA_DIRECTION_TO_DEVICE, 1419 MEMTXATTRS_UNSPECIFIED); 1420 if (!sg[i].iov_base) { 1421 error_report("virtio: error trying to map MMIO memory"); 1422 exit(1); 1423 } 1424 if (len != sg[i].iov_len) { 1425 error_report("virtio: unexpected memory split"); 1426 exit(1); 1427 } 1428 } 1429 } 1430 1431 void virtqueue_map(VirtIODevice *vdev, VirtQueueElement *elem) 1432 { 1433 virtqueue_map_iovec(vdev, elem->in_sg, elem->in_addr, elem->in_num, true); 1434 virtqueue_map_iovec(vdev, elem->out_sg, elem->out_addr, elem->out_num, 1435 false); 1436 } 1437 1438 static void *virtqueue_alloc_element(size_t sz, unsigned out_num, unsigned in_num) 1439 { 1440 VirtQueueElement *elem; 1441 size_t in_addr_ofs = QEMU_ALIGN_UP(sz, __alignof__(elem->in_addr[0])); 1442 size_t out_addr_ofs = in_addr_ofs + in_num * sizeof(elem->in_addr[0]); 1443 size_t out_addr_end = out_addr_ofs + out_num * sizeof(elem->out_addr[0]); 1444 size_t in_sg_ofs = QEMU_ALIGN_UP(out_addr_end, __alignof__(elem->in_sg[0])); 1445 size_t out_sg_ofs = in_sg_ofs + in_num * sizeof(elem->in_sg[0]); 1446 size_t out_sg_end = out_sg_ofs + out_num * sizeof(elem->out_sg[0]); 1447 1448 assert(sz >= sizeof(VirtQueueElement)); 1449 elem = g_malloc(out_sg_end); 1450 trace_virtqueue_alloc_element(elem, sz, in_num, out_num); 1451 elem->out_num = out_num; 1452 elem->in_num = in_num; 1453 elem->in_addr = (void *)elem + in_addr_ofs; 1454 elem->out_addr = (void *)elem + out_addr_ofs; 1455 elem->in_sg = (void *)elem + in_sg_ofs; 1456 elem->out_sg = (void *)elem + out_sg_ofs; 1457 return elem; 1458 } 1459 1460 static void *virtqueue_split_pop(VirtQueue *vq, size_t sz) 1461 { 1462 unsigned int i, head, max; 1463 VRingMemoryRegionCaches *caches; 1464 MemoryRegionCache indirect_desc_cache = MEMORY_REGION_CACHE_INVALID; 1465 MemoryRegionCache *desc_cache; 1466 int64_t len; 1467 VirtIODevice *vdev = vq->vdev; 1468 VirtQueueElement *elem = NULL; 1469 unsigned out_num, in_num, elem_entries; 1470 hwaddr addr[VIRTQUEUE_MAX_SIZE]; 1471 struct iovec iov[VIRTQUEUE_MAX_SIZE]; 1472 VRingDesc desc; 1473 int rc; 1474 1475 RCU_READ_LOCK_GUARD(); 1476 if (virtio_queue_empty_rcu(vq)) { 1477 goto done; 1478 } 1479 /* Needed after virtio_queue_empty(), see comment in 1480 * virtqueue_num_heads(). */ 1481 smp_rmb(); 1482 1483 /* When we start there are none of either input nor output. */ 1484 out_num = in_num = elem_entries = 0; 1485 1486 max = vq->vring.num; 1487 1488 if (vq->inuse >= vq->vring.num) { 1489 virtio_error(vdev, "Virtqueue size exceeded"); 1490 goto done; 1491 } 1492 1493 if (!virtqueue_get_head(vq, vq->last_avail_idx++, &head)) { 1494 goto done; 1495 } 1496 1497 if (virtio_vdev_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX)) { 1498 vring_set_avail_event(vq, vq->last_avail_idx); 1499 } 1500 1501 i = head; 1502 1503 caches = vring_get_region_caches(vq); 1504 if (!caches) { 1505 virtio_error(vdev, "Region caches not initialized"); 1506 goto done; 1507 } 1508 1509 if (caches->desc.len < max * sizeof(VRingDesc)) { 1510 virtio_error(vdev, "Cannot map descriptor ring"); 1511 goto done; 1512 } 1513 1514 desc_cache = &caches->desc; 1515 vring_split_desc_read(vdev, &desc, desc_cache, i); 1516 if (desc.flags & VRING_DESC_F_INDIRECT) { 1517 if (!desc.len || (desc.len % sizeof(VRingDesc))) { 1518 virtio_error(vdev, "Invalid size for indirect buffer table"); 1519 goto done; 1520 } 1521 1522 /* loop over the indirect descriptor table */ 1523 len = address_space_cache_init(&indirect_desc_cache, vdev->dma_as, 1524 desc.addr, desc.len, false); 1525 desc_cache = &indirect_desc_cache; 1526 if (len < desc.len) { 1527 virtio_error(vdev, "Cannot map indirect buffer"); 1528 goto done; 1529 } 1530 1531 max = desc.len / sizeof(VRingDesc); 1532 i = 0; 1533 vring_split_desc_read(vdev, &desc, desc_cache, i); 1534 } 1535 1536 /* Collect all the descriptors */ 1537 do { 1538 bool map_ok; 1539 1540 if (desc.flags & VRING_DESC_F_WRITE) { 1541 map_ok = virtqueue_map_desc(vdev, &in_num, addr + out_num, 1542 iov + out_num, 1543 VIRTQUEUE_MAX_SIZE - out_num, true, 1544 desc.addr, desc.len); 1545 } else { 1546 if (in_num) { 1547 virtio_error(vdev, "Incorrect order for descriptors"); 1548 goto err_undo_map; 1549 } 1550 map_ok = virtqueue_map_desc(vdev, &out_num, addr, iov, 1551 VIRTQUEUE_MAX_SIZE, false, 1552 desc.addr, desc.len); 1553 } 1554 if (!map_ok) { 1555 goto err_undo_map; 1556 } 1557 1558 /* If we've got too many, that implies a descriptor loop. */ 1559 if (++elem_entries > max) { 1560 virtio_error(vdev, "Looped descriptor"); 1561 goto err_undo_map; 1562 } 1563 1564 rc = virtqueue_split_read_next_desc(vdev, &desc, desc_cache, max, &i); 1565 } while (rc == VIRTQUEUE_READ_DESC_MORE); 1566 1567 if (rc == VIRTQUEUE_READ_DESC_ERROR) { 1568 goto err_undo_map; 1569 } 1570 1571 /* Now copy what we have collected and mapped */ 1572 elem = virtqueue_alloc_element(sz, out_num, in_num); 1573 elem->index = head; 1574 elem->ndescs = 1; 1575 for (i = 0; i < out_num; i++) { 1576 elem->out_addr[i] = addr[i]; 1577 elem->out_sg[i] = iov[i]; 1578 } 1579 for (i = 0; i < in_num; i++) { 1580 elem->in_addr[i] = addr[out_num + i]; 1581 elem->in_sg[i] = iov[out_num + i]; 1582 } 1583 1584 vq->inuse++; 1585 1586 trace_virtqueue_pop(vq, elem, elem->in_num, elem->out_num); 1587 done: 1588 address_space_cache_destroy(&indirect_desc_cache); 1589 1590 return elem; 1591 1592 err_undo_map: 1593 virtqueue_undo_map_desc(out_num, in_num, iov); 1594 goto done; 1595 } 1596 1597 static void *virtqueue_packed_pop(VirtQueue *vq, size_t sz) 1598 { 1599 unsigned int i, max; 1600 VRingMemoryRegionCaches *caches; 1601 MemoryRegionCache indirect_desc_cache = MEMORY_REGION_CACHE_INVALID; 1602 MemoryRegionCache *desc_cache; 1603 int64_t len; 1604 VirtIODevice *vdev = vq->vdev; 1605 VirtQueueElement *elem = NULL; 1606 unsigned out_num, in_num, elem_entries; 1607 hwaddr addr[VIRTQUEUE_MAX_SIZE]; 1608 struct iovec iov[VIRTQUEUE_MAX_SIZE]; 1609 VRingPackedDesc desc; 1610 uint16_t id; 1611 int rc; 1612 1613 RCU_READ_LOCK_GUARD(); 1614 if (virtio_queue_packed_empty_rcu(vq)) { 1615 goto done; 1616 } 1617 1618 /* When we start there are none of either input nor output. */ 1619 out_num = in_num = elem_entries = 0; 1620 1621 max = vq->vring.num; 1622 1623 if (vq->inuse >= vq->vring.num) { 1624 virtio_error(vdev, "Virtqueue size exceeded"); 1625 goto done; 1626 } 1627 1628 i = vq->last_avail_idx; 1629 1630 caches = vring_get_region_caches(vq); 1631 if (!caches) { 1632 virtio_error(vdev, "Region caches not initialized"); 1633 goto done; 1634 } 1635 1636 if (caches->desc.len < max * sizeof(VRingDesc)) { 1637 virtio_error(vdev, "Cannot map descriptor ring"); 1638 goto done; 1639 } 1640 1641 desc_cache = &caches->desc; 1642 vring_packed_desc_read(vdev, &desc, desc_cache, i, true); 1643 id = desc.id; 1644 if (desc.flags & VRING_DESC_F_INDIRECT) { 1645 if (desc.len % sizeof(VRingPackedDesc)) { 1646 virtio_error(vdev, "Invalid size for indirect buffer table"); 1647 goto done; 1648 } 1649 1650 /* loop over the indirect descriptor table */ 1651 len = address_space_cache_init(&indirect_desc_cache, vdev->dma_as, 1652 desc.addr, desc.len, false); 1653 desc_cache = &indirect_desc_cache; 1654 if (len < desc.len) { 1655 virtio_error(vdev, "Cannot map indirect buffer"); 1656 goto done; 1657 } 1658 1659 max = desc.len / sizeof(VRingPackedDesc); 1660 i = 0; 1661 vring_packed_desc_read(vdev, &desc, desc_cache, i, false); 1662 } 1663 1664 /* Collect all the descriptors */ 1665 do { 1666 bool map_ok; 1667 1668 if (desc.flags & VRING_DESC_F_WRITE) { 1669 map_ok = virtqueue_map_desc(vdev, &in_num, addr + out_num, 1670 iov + out_num, 1671 VIRTQUEUE_MAX_SIZE - out_num, true, 1672 desc.addr, desc.len); 1673 } else { 1674 if (in_num) { 1675 virtio_error(vdev, "Incorrect order for descriptors"); 1676 goto err_undo_map; 1677 } 1678 map_ok = virtqueue_map_desc(vdev, &out_num, addr, iov, 1679 VIRTQUEUE_MAX_SIZE, false, 1680 desc.addr, desc.len); 1681 } 1682 if (!map_ok) { 1683 goto err_undo_map; 1684 } 1685 1686 /* If we've got too many, that implies a descriptor loop. */ 1687 if (++elem_entries > max) { 1688 virtio_error(vdev, "Looped descriptor"); 1689 goto err_undo_map; 1690 } 1691 1692 rc = virtqueue_packed_read_next_desc(vq, &desc, desc_cache, max, &i, 1693 desc_cache == 1694 &indirect_desc_cache); 1695 } while (rc == VIRTQUEUE_READ_DESC_MORE); 1696 1697 /* Now copy what we have collected and mapped */ 1698 elem = virtqueue_alloc_element(sz, out_num, in_num); 1699 for (i = 0; i < out_num; i++) { 1700 elem->out_addr[i] = addr[i]; 1701 elem->out_sg[i] = iov[i]; 1702 } 1703 for (i = 0; i < in_num; i++) { 1704 elem->in_addr[i] = addr[out_num + i]; 1705 elem->in_sg[i] = iov[out_num + i]; 1706 } 1707 1708 elem->index = id; 1709 elem->ndescs = (desc_cache == &indirect_desc_cache) ? 1 : elem_entries; 1710 vq->last_avail_idx += elem->ndescs; 1711 vq->inuse += elem->ndescs; 1712 1713 if (vq->last_avail_idx >= vq->vring.num) { 1714 vq->last_avail_idx -= vq->vring.num; 1715 vq->last_avail_wrap_counter ^= 1; 1716 } 1717 1718 vq->shadow_avail_idx = vq->last_avail_idx; 1719 vq->shadow_avail_wrap_counter = vq->last_avail_wrap_counter; 1720 1721 trace_virtqueue_pop(vq, elem, elem->in_num, elem->out_num); 1722 done: 1723 address_space_cache_destroy(&indirect_desc_cache); 1724 1725 return elem; 1726 1727 err_undo_map: 1728 virtqueue_undo_map_desc(out_num, in_num, iov); 1729 goto done; 1730 } 1731 1732 void *virtqueue_pop(VirtQueue *vq, size_t sz) 1733 { 1734 if (virtio_device_disabled(vq->vdev)) { 1735 return NULL; 1736 } 1737 1738 if (virtio_vdev_has_feature(vq->vdev, VIRTIO_F_RING_PACKED)) { 1739 return virtqueue_packed_pop(vq, sz); 1740 } else { 1741 return virtqueue_split_pop(vq, sz); 1742 } 1743 } 1744 1745 static unsigned int virtqueue_packed_drop_all(VirtQueue *vq) 1746 { 1747 VRingMemoryRegionCaches *caches; 1748 MemoryRegionCache *desc_cache; 1749 unsigned int dropped = 0; 1750 VirtQueueElement elem = {}; 1751 VirtIODevice *vdev = vq->vdev; 1752 VRingPackedDesc desc; 1753 1754 RCU_READ_LOCK_GUARD(); 1755 1756 caches = vring_get_region_caches(vq); 1757 if (!caches) { 1758 return 0; 1759 } 1760 1761 desc_cache = &caches->desc; 1762 1763 virtio_queue_set_notification(vq, 0); 1764 1765 while (vq->inuse < vq->vring.num) { 1766 unsigned int idx = vq->last_avail_idx; 1767 /* 1768 * works similar to virtqueue_pop but does not map buffers 1769 * and does not allocate any memory. 1770 */ 1771 vring_packed_desc_read(vdev, &desc, desc_cache, 1772 vq->last_avail_idx , true); 1773 if (!is_desc_avail(desc.flags, vq->last_avail_wrap_counter)) { 1774 break; 1775 } 1776 elem.index = desc.id; 1777 elem.ndescs = 1; 1778 while (virtqueue_packed_read_next_desc(vq, &desc, desc_cache, 1779 vq->vring.num, &idx, false)) { 1780 ++elem.ndescs; 1781 } 1782 /* 1783 * immediately push the element, nothing to unmap 1784 * as both in_num and out_num are set to 0. 1785 */ 1786 virtqueue_push(vq, &elem, 0); 1787 dropped++; 1788 vq->last_avail_idx += elem.ndescs; 1789 if (vq->last_avail_idx >= vq->vring.num) { 1790 vq->last_avail_idx -= vq->vring.num; 1791 vq->last_avail_wrap_counter ^= 1; 1792 } 1793 } 1794 1795 return dropped; 1796 } 1797 1798 static unsigned int virtqueue_split_drop_all(VirtQueue *vq) 1799 { 1800 unsigned int dropped = 0; 1801 VirtQueueElement elem = {}; 1802 VirtIODevice *vdev = vq->vdev; 1803 bool fEventIdx = virtio_vdev_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX); 1804 1805 while (!virtio_queue_empty(vq) && vq->inuse < vq->vring.num) { 1806 /* works similar to virtqueue_pop but does not map buffers 1807 * and does not allocate any memory */ 1808 smp_rmb(); 1809 if (!virtqueue_get_head(vq, vq->last_avail_idx, &elem.index)) { 1810 break; 1811 } 1812 vq->inuse++; 1813 vq->last_avail_idx++; 1814 if (fEventIdx) { 1815 vring_set_avail_event(vq, vq->last_avail_idx); 1816 } 1817 /* immediately push the element, nothing to unmap 1818 * as both in_num and out_num are set to 0 */ 1819 virtqueue_push(vq, &elem, 0); 1820 dropped++; 1821 } 1822 1823 return dropped; 1824 } 1825 1826 /* virtqueue_drop_all: 1827 * @vq: The #VirtQueue 1828 * Drops all queued buffers and indicates them to the guest 1829 * as if they are done. Useful when buffers can not be 1830 * processed but must be returned to the guest. 1831 */ 1832 unsigned int virtqueue_drop_all(VirtQueue *vq) 1833 { 1834 struct VirtIODevice *vdev = vq->vdev; 1835 1836 if (virtio_device_disabled(vq->vdev)) { 1837 return 0; 1838 } 1839 1840 if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { 1841 return virtqueue_packed_drop_all(vq); 1842 } else { 1843 return virtqueue_split_drop_all(vq); 1844 } 1845 } 1846 1847 /* Reading and writing a structure directly to QEMUFile is *awful*, but 1848 * it is what QEMU has always done by mistake. We can change it sooner 1849 * or later by bumping the version number of the affected vm states. 1850 * In the meanwhile, since the in-memory layout of VirtQueueElement 1851 * has changed, we need to marshal to and from the layout that was 1852 * used before the change. 1853 */ 1854 typedef struct VirtQueueElementOld { 1855 unsigned int index; 1856 unsigned int out_num; 1857 unsigned int in_num; 1858 hwaddr in_addr[VIRTQUEUE_MAX_SIZE]; 1859 hwaddr out_addr[VIRTQUEUE_MAX_SIZE]; 1860 struct iovec in_sg[VIRTQUEUE_MAX_SIZE]; 1861 struct iovec out_sg[VIRTQUEUE_MAX_SIZE]; 1862 } VirtQueueElementOld; 1863 1864 void *qemu_get_virtqueue_element(VirtIODevice *vdev, QEMUFile *f, size_t sz) 1865 { 1866 VirtQueueElement *elem; 1867 VirtQueueElementOld data; 1868 int i; 1869 1870 qemu_get_buffer(f, (uint8_t *)&data, sizeof(VirtQueueElementOld)); 1871 1872 /* TODO: teach all callers that this can fail, and return failure instead 1873 * of asserting here. 1874 * This is just one thing (there are probably more) that must be 1875 * fixed before we can allow NDEBUG compilation. 1876 */ 1877 assert(ARRAY_SIZE(data.in_addr) >= data.in_num); 1878 assert(ARRAY_SIZE(data.out_addr) >= data.out_num); 1879 1880 elem = virtqueue_alloc_element(sz, data.out_num, data.in_num); 1881 elem->index = data.index; 1882 1883 for (i = 0; i < elem->in_num; i++) { 1884 elem->in_addr[i] = data.in_addr[i]; 1885 } 1886 1887 for (i = 0; i < elem->out_num; i++) { 1888 elem->out_addr[i] = data.out_addr[i]; 1889 } 1890 1891 for (i = 0; i < elem->in_num; i++) { 1892 /* Base is overwritten by virtqueue_map. */ 1893 elem->in_sg[i].iov_base = 0; 1894 elem->in_sg[i].iov_len = data.in_sg[i].iov_len; 1895 } 1896 1897 for (i = 0; i < elem->out_num; i++) { 1898 /* Base is overwritten by virtqueue_map. */ 1899 elem->out_sg[i].iov_base = 0; 1900 elem->out_sg[i].iov_len = data.out_sg[i].iov_len; 1901 } 1902 1903 if (virtio_host_has_feature(vdev, VIRTIO_F_RING_PACKED)) { 1904 qemu_get_be32s(f, &elem->ndescs); 1905 } 1906 1907 virtqueue_map(vdev, elem); 1908 return elem; 1909 } 1910 1911 void qemu_put_virtqueue_element(VirtIODevice *vdev, QEMUFile *f, 1912 VirtQueueElement *elem) 1913 { 1914 VirtQueueElementOld data; 1915 int i; 1916 1917 memset(&data, 0, sizeof(data)); 1918 data.index = elem->index; 1919 data.in_num = elem->in_num; 1920 data.out_num = elem->out_num; 1921 1922 for (i = 0; i < elem->in_num; i++) { 1923 data.in_addr[i] = elem->in_addr[i]; 1924 } 1925 1926 for (i = 0; i < elem->out_num; i++) { 1927 data.out_addr[i] = elem->out_addr[i]; 1928 } 1929 1930 for (i = 0; i < elem->in_num; i++) { 1931 /* Base is overwritten by virtqueue_map when loading. Do not 1932 * save it, as it would leak the QEMU address space layout. */ 1933 data.in_sg[i].iov_len = elem->in_sg[i].iov_len; 1934 } 1935 1936 for (i = 0; i < elem->out_num; i++) { 1937 /* Do not save iov_base as above. */ 1938 data.out_sg[i].iov_len = elem->out_sg[i].iov_len; 1939 } 1940 1941 if (virtio_host_has_feature(vdev, VIRTIO_F_RING_PACKED)) { 1942 qemu_put_be32s(f, &elem->ndescs); 1943 } 1944 1945 qemu_put_buffer(f, (uint8_t *)&data, sizeof(VirtQueueElementOld)); 1946 } 1947 1948 /* virtio device */ 1949 static void virtio_notify_vector(VirtIODevice *vdev, uint16_t vector) 1950 { 1951 BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); 1952 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); 1953 1954 if (virtio_device_disabled(vdev)) { 1955 return; 1956 } 1957 1958 if (k->notify) { 1959 k->notify(qbus->parent, vector); 1960 } 1961 } 1962 1963 void virtio_update_irq(VirtIODevice *vdev) 1964 { 1965 virtio_notify_vector(vdev, VIRTIO_NO_VECTOR); 1966 } 1967 1968 static int virtio_validate_features(VirtIODevice *vdev) 1969 { 1970 VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); 1971 1972 if (virtio_host_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM) && 1973 !virtio_vdev_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM)) { 1974 return -EFAULT; 1975 } 1976 1977 if (k->validate_features) { 1978 return k->validate_features(vdev); 1979 } else { 1980 return 0; 1981 } 1982 } 1983 1984 int virtio_set_status(VirtIODevice *vdev, uint8_t val) 1985 { 1986 VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); 1987 trace_virtio_set_status(vdev, val); 1988 1989 if (virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) { 1990 if (!(vdev->status & VIRTIO_CONFIG_S_FEATURES_OK) && 1991 val & VIRTIO_CONFIG_S_FEATURES_OK) { 1992 int ret = virtio_validate_features(vdev); 1993 1994 if (ret) { 1995 return ret; 1996 } 1997 } 1998 } 1999 2000 if ((vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) != 2001 (val & VIRTIO_CONFIG_S_DRIVER_OK)) { 2002 virtio_set_started(vdev, val & VIRTIO_CONFIG_S_DRIVER_OK); 2003 } 2004 2005 if (k->set_status) { 2006 k->set_status(vdev, val); 2007 } 2008 vdev->status = val; 2009 2010 return 0; 2011 } 2012 2013 static enum virtio_device_endian virtio_default_endian(void) 2014 { 2015 if (target_words_bigendian()) { 2016 return VIRTIO_DEVICE_ENDIAN_BIG; 2017 } else { 2018 return VIRTIO_DEVICE_ENDIAN_LITTLE; 2019 } 2020 } 2021 2022 static enum virtio_device_endian virtio_current_cpu_endian(void) 2023 { 2024 if (cpu_virtio_is_big_endian(current_cpu)) { 2025 return VIRTIO_DEVICE_ENDIAN_BIG; 2026 } else { 2027 return VIRTIO_DEVICE_ENDIAN_LITTLE; 2028 } 2029 } 2030 2031 void virtio_reset(void *opaque) 2032 { 2033 VirtIODevice *vdev = opaque; 2034 VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); 2035 int i; 2036 2037 virtio_set_status(vdev, 0); 2038 if (current_cpu) { 2039 /* Guest initiated reset */ 2040 vdev->device_endian = virtio_current_cpu_endian(); 2041 } else { 2042 /* System reset */ 2043 vdev->device_endian = virtio_default_endian(); 2044 } 2045 2046 if (k->reset) { 2047 k->reset(vdev); 2048 } 2049 2050 vdev->start_on_kick = false; 2051 vdev->started = false; 2052 vdev->broken = false; 2053 vdev->guest_features = 0; 2054 vdev->queue_sel = 0; 2055 vdev->status = 0; 2056 vdev->disabled = false; 2057 qatomic_set(&vdev->isr, 0); 2058 vdev->config_vector = VIRTIO_NO_VECTOR; 2059 virtio_notify_vector(vdev, vdev->config_vector); 2060 2061 for(i = 0; i < VIRTIO_QUEUE_MAX; i++) { 2062 vdev->vq[i].vring.desc = 0; 2063 vdev->vq[i].vring.avail = 0; 2064 vdev->vq[i].vring.used = 0; 2065 vdev->vq[i].last_avail_idx = 0; 2066 vdev->vq[i].shadow_avail_idx = 0; 2067 vdev->vq[i].used_idx = 0; 2068 vdev->vq[i].last_avail_wrap_counter = true; 2069 vdev->vq[i].shadow_avail_wrap_counter = true; 2070 vdev->vq[i].used_wrap_counter = true; 2071 virtio_queue_set_vector(vdev, i, VIRTIO_NO_VECTOR); 2072 vdev->vq[i].signalled_used = 0; 2073 vdev->vq[i].signalled_used_valid = false; 2074 vdev->vq[i].notification = true; 2075 vdev->vq[i].vring.num = vdev->vq[i].vring.num_default; 2076 vdev->vq[i].inuse = 0; 2077 virtio_virtqueue_reset_region_cache(&vdev->vq[i]); 2078 } 2079 } 2080 2081 uint32_t virtio_config_readb(VirtIODevice *vdev, uint32_t addr) 2082 { 2083 VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); 2084 uint8_t val; 2085 2086 if (addr + sizeof(val) > vdev->config_len) { 2087 return (uint32_t)-1; 2088 } 2089 2090 k->get_config(vdev, vdev->config); 2091 2092 val = ldub_p(vdev->config + addr); 2093 return val; 2094 } 2095 2096 uint32_t virtio_config_readw(VirtIODevice *vdev, uint32_t addr) 2097 { 2098 VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); 2099 uint16_t val; 2100 2101 if (addr + sizeof(val) > vdev->config_len) { 2102 return (uint32_t)-1; 2103 } 2104 2105 k->get_config(vdev, vdev->config); 2106 2107 val = lduw_p(vdev->config + addr); 2108 return val; 2109 } 2110 2111 uint32_t virtio_config_readl(VirtIODevice *vdev, uint32_t addr) 2112 { 2113 VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); 2114 uint32_t val; 2115 2116 if (addr + sizeof(val) > vdev->config_len) { 2117 return (uint32_t)-1; 2118 } 2119 2120 k->get_config(vdev, vdev->config); 2121 2122 val = ldl_p(vdev->config + addr); 2123 return val; 2124 } 2125 2126 void virtio_config_writeb(VirtIODevice *vdev, uint32_t addr, uint32_t data) 2127 { 2128 VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); 2129 uint8_t val = data; 2130 2131 if (addr + sizeof(val) > vdev->config_len) { 2132 return; 2133 } 2134 2135 stb_p(vdev->config + addr, val); 2136 2137 if (k->set_config) { 2138 k->set_config(vdev, vdev->config); 2139 } 2140 } 2141 2142 void virtio_config_writew(VirtIODevice *vdev, uint32_t addr, uint32_t data) 2143 { 2144 VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); 2145 uint16_t val = data; 2146 2147 if (addr + sizeof(val) > vdev->config_len) { 2148 return; 2149 } 2150 2151 stw_p(vdev->config + addr, val); 2152 2153 if (k->set_config) { 2154 k->set_config(vdev, vdev->config); 2155 } 2156 } 2157 2158 void virtio_config_writel(VirtIODevice *vdev, uint32_t addr, uint32_t data) 2159 { 2160 VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); 2161 uint32_t val = data; 2162 2163 if (addr + sizeof(val) > vdev->config_len) { 2164 return; 2165 } 2166 2167 stl_p(vdev->config + addr, val); 2168 2169 if (k->set_config) { 2170 k->set_config(vdev, vdev->config); 2171 } 2172 } 2173 2174 uint32_t virtio_config_modern_readb(VirtIODevice *vdev, uint32_t addr) 2175 { 2176 VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); 2177 uint8_t val; 2178 2179 if (addr + sizeof(val) > vdev->config_len) { 2180 return (uint32_t)-1; 2181 } 2182 2183 k->get_config(vdev, vdev->config); 2184 2185 val = ldub_p(vdev->config + addr); 2186 return val; 2187 } 2188 2189 uint32_t virtio_config_modern_readw(VirtIODevice *vdev, uint32_t addr) 2190 { 2191 VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); 2192 uint16_t val; 2193 2194 if (addr + sizeof(val) > vdev->config_len) { 2195 return (uint32_t)-1; 2196 } 2197 2198 k->get_config(vdev, vdev->config); 2199 2200 val = lduw_le_p(vdev->config + addr); 2201 return val; 2202 } 2203 2204 uint32_t virtio_config_modern_readl(VirtIODevice *vdev, uint32_t addr) 2205 { 2206 VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); 2207 uint32_t val; 2208 2209 if (addr + sizeof(val) > vdev->config_len) { 2210 return (uint32_t)-1; 2211 } 2212 2213 k->get_config(vdev, vdev->config); 2214 2215 val = ldl_le_p(vdev->config + addr); 2216 return val; 2217 } 2218 2219 void virtio_config_modern_writeb(VirtIODevice *vdev, 2220 uint32_t addr, uint32_t data) 2221 { 2222 VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); 2223 uint8_t val = data; 2224 2225 if (addr + sizeof(val) > vdev->config_len) { 2226 return; 2227 } 2228 2229 stb_p(vdev->config + addr, val); 2230 2231 if (k->set_config) { 2232 k->set_config(vdev, vdev->config); 2233 } 2234 } 2235 2236 void virtio_config_modern_writew(VirtIODevice *vdev, 2237 uint32_t addr, uint32_t data) 2238 { 2239 VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); 2240 uint16_t val = data; 2241 2242 if (addr + sizeof(val) > vdev->config_len) { 2243 return; 2244 } 2245 2246 stw_le_p(vdev->config + addr, val); 2247 2248 if (k->set_config) { 2249 k->set_config(vdev, vdev->config); 2250 } 2251 } 2252 2253 void virtio_config_modern_writel(VirtIODevice *vdev, 2254 uint32_t addr, uint32_t data) 2255 { 2256 VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); 2257 uint32_t val = data; 2258 2259 if (addr + sizeof(val) > vdev->config_len) { 2260 return; 2261 } 2262 2263 stl_le_p(vdev->config + addr, val); 2264 2265 if (k->set_config) { 2266 k->set_config(vdev, vdev->config); 2267 } 2268 } 2269 2270 void virtio_queue_set_addr(VirtIODevice *vdev, int n, hwaddr addr) 2271 { 2272 if (!vdev->vq[n].vring.num) { 2273 return; 2274 } 2275 vdev->vq[n].vring.desc = addr; 2276 virtio_queue_update_rings(vdev, n); 2277 } 2278 2279 hwaddr virtio_queue_get_addr(VirtIODevice *vdev, int n) 2280 { 2281 return vdev->vq[n].vring.desc; 2282 } 2283 2284 void virtio_queue_set_rings(VirtIODevice *vdev, int n, hwaddr desc, 2285 hwaddr avail, hwaddr used) 2286 { 2287 if (!vdev->vq[n].vring.num) { 2288 return; 2289 } 2290 vdev->vq[n].vring.desc = desc; 2291 vdev->vq[n].vring.avail = avail; 2292 vdev->vq[n].vring.used = used; 2293 virtio_init_region_cache(vdev, n); 2294 } 2295 2296 void virtio_queue_set_num(VirtIODevice *vdev, int n, int num) 2297 { 2298 /* Don't allow guest to flip queue between existent and 2299 * nonexistent states, or to set it to an invalid size. 2300 */ 2301 if (!!num != !!vdev->vq[n].vring.num || 2302 num > VIRTQUEUE_MAX_SIZE || 2303 num < 0) { 2304 return; 2305 } 2306 vdev->vq[n].vring.num = num; 2307 } 2308 2309 VirtQueue *virtio_vector_first_queue(VirtIODevice *vdev, uint16_t vector) 2310 { 2311 return QLIST_FIRST(&vdev->vector_queues[vector]); 2312 } 2313 2314 VirtQueue *virtio_vector_next_queue(VirtQueue *vq) 2315 { 2316 return QLIST_NEXT(vq, node); 2317 } 2318 2319 int virtio_queue_get_num(VirtIODevice *vdev, int n) 2320 { 2321 return vdev->vq[n].vring.num; 2322 } 2323 2324 int virtio_queue_get_max_num(VirtIODevice *vdev, int n) 2325 { 2326 return vdev->vq[n].vring.num_default; 2327 } 2328 2329 int virtio_get_num_queues(VirtIODevice *vdev) 2330 { 2331 int i; 2332 2333 for (i = 0; i < VIRTIO_QUEUE_MAX; i++) { 2334 if (!virtio_queue_get_num(vdev, i)) { 2335 break; 2336 } 2337 } 2338 2339 return i; 2340 } 2341 2342 void virtio_queue_set_align(VirtIODevice *vdev, int n, int align) 2343 { 2344 BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); 2345 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); 2346 2347 /* virtio-1 compliant devices cannot change the alignment */ 2348 if (virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) { 2349 error_report("tried to modify queue alignment for virtio-1 device"); 2350 return; 2351 } 2352 /* Check that the transport told us it was going to do this 2353 * (so a buggy transport will immediately assert rather than 2354 * silently failing to migrate this state) 2355 */ 2356 assert(k->has_variable_vring_alignment); 2357 2358 if (align) { 2359 vdev->vq[n].vring.align = align; 2360 virtio_queue_update_rings(vdev, n); 2361 } 2362 } 2363 2364 static void virtio_queue_notify_vq(VirtQueue *vq) 2365 { 2366 if (vq->vring.desc && vq->handle_output) { 2367 VirtIODevice *vdev = vq->vdev; 2368 2369 if (unlikely(vdev->broken)) { 2370 return; 2371 } 2372 2373 trace_virtio_queue_notify(vdev, vq - vdev->vq, vq); 2374 vq->handle_output(vdev, vq); 2375 2376 if (unlikely(vdev->start_on_kick)) { 2377 virtio_set_started(vdev, true); 2378 } 2379 } 2380 } 2381 2382 void virtio_queue_notify(VirtIODevice *vdev, int n) 2383 { 2384 VirtQueue *vq = &vdev->vq[n]; 2385 2386 if (unlikely(!vq->vring.desc || vdev->broken)) { 2387 return; 2388 } 2389 2390 trace_virtio_queue_notify(vdev, vq - vdev->vq, vq); 2391 if (vq->host_notifier_enabled) { 2392 event_notifier_set(&vq->host_notifier); 2393 } else if (vq->handle_output) { 2394 vq->handle_output(vdev, vq); 2395 2396 if (unlikely(vdev->start_on_kick)) { 2397 virtio_set_started(vdev, true); 2398 } 2399 } 2400 } 2401 2402 uint16_t virtio_queue_vector(VirtIODevice *vdev, int n) 2403 { 2404 return n < VIRTIO_QUEUE_MAX ? vdev->vq[n].vector : 2405 VIRTIO_NO_VECTOR; 2406 } 2407 2408 void virtio_queue_set_vector(VirtIODevice *vdev, int n, uint16_t vector) 2409 { 2410 VirtQueue *vq = &vdev->vq[n]; 2411 2412 if (n < VIRTIO_QUEUE_MAX) { 2413 if (vdev->vector_queues && 2414 vdev->vq[n].vector != VIRTIO_NO_VECTOR) { 2415 QLIST_REMOVE(vq, node); 2416 } 2417 vdev->vq[n].vector = vector; 2418 if (vdev->vector_queues && 2419 vector != VIRTIO_NO_VECTOR) { 2420 QLIST_INSERT_HEAD(&vdev->vector_queues[vector], vq, node); 2421 } 2422 } 2423 } 2424 2425 VirtQueue *virtio_add_queue(VirtIODevice *vdev, int queue_size, 2426 VirtIOHandleOutput handle_output) 2427 { 2428 int i; 2429 2430 for (i = 0; i < VIRTIO_QUEUE_MAX; i++) { 2431 if (vdev->vq[i].vring.num == 0) 2432 break; 2433 } 2434 2435 if (i == VIRTIO_QUEUE_MAX || queue_size > VIRTQUEUE_MAX_SIZE) 2436 abort(); 2437 2438 vdev->vq[i].vring.num = queue_size; 2439 vdev->vq[i].vring.num_default = queue_size; 2440 vdev->vq[i].vring.align = VIRTIO_PCI_VRING_ALIGN; 2441 vdev->vq[i].handle_output = handle_output; 2442 vdev->vq[i].used_elems = g_new0(VirtQueueElement, queue_size); 2443 2444 return &vdev->vq[i]; 2445 } 2446 2447 void virtio_delete_queue(VirtQueue *vq) 2448 { 2449 vq->vring.num = 0; 2450 vq->vring.num_default = 0; 2451 vq->handle_output = NULL; 2452 g_free(vq->used_elems); 2453 vq->used_elems = NULL; 2454 virtio_virtqueue_reset_region_cache(vq); 2455 } 2456 2457 void virtio_del_queue(VirtIODevice *vdev, int n) 2458 { 2459 if (n < 0 || n >= VIRTIO_QUEUE_MAX) { 2460 abort(); 2461 } 2462 2463 virtio_delete_queue(&vdev->vq[n]); 2464 } 2465 2466 static void virtio_set_isr(VirtIODevice *vdev, int value) 2467 { 2468 uint8_t old = qatomic_read(&vdev->isr); 2469 2470 /* Do not write ISR if it does not change, so that its cacheline remains 2471 * shared in the common case where the guest does not read it. 2472 */ 2473 if ((old & value) != value) { 2474 qatomic_or(&vdev->isr, value); 2475 } 2476 } 2477 2478 /* Called within rcu_read_lock(). */ 2479 static bool virtio_split_should_notify(VirtIODevice *vdev, VirtQueue *vq) 2480 { 2481 uint16_t old, new; 2482 bool v; 2483 /* We need to expose used array entries before checking used event. */ 2484 smp_mb(); 2485 /* Always notify when queue is empty (when feature acknowledge) */ 2486 if (virtio_vdev_has_feature(vdev, VIRTIO_F_NOTIFY_ON_EMPTY) && 2487 !vq->inuse && virtio_queue_empty(vq)) { 2488 return true; 2489 } 2490 2491 if (!virtio_vdev_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX)) { 2492 return !(vring_avail_flags(vq) & VRING_AVAIL_F_NO_INTERRUPT); 2493 } 2494 2495 v = vq->signalled_used_valid; 2496 vq->signalled_used_valid = true; 2497 old = vq->signalled_used; 2498 new = vq->signalled_used = vq->used_idx; 2499 return !v || vring_need_event(vring_get_used_event(vq), new, old); 2500 } 2501 2502 static bool vring_packed_need_event(VirtQueue *vq, bool wrap, 2503 uint16_t off_wrap, uint16_t new, 2504 uint16_t old) 2505 { 2506 int off = off_wrap & ~(1 << 15); 2507 2508 if (wrap != off_wrap >> 15) { 2509 off -= vq->vring.num; 2510 } 2511 2512 return vring_need_event(off, new, old); 2513 } 2514 2515 /* Called within rcu_read_lock(). */ 2516 static bool virtio_packed_should_notify(VirtIODevice *vdev, VirtQueue *vq) 2517 { 2518 VRingPackedDescEvent e; 2519 uint16_t old, new; 2520 bool v; 2521 VRingMemoryRegionCaches *caches; 2522 2523 caches = vring_get_region_caches(vq); 2524 if (!caches) { 2525 return false; 2526 } 2527 2528 vring_packed_event_read(vdev, &caches->avail, &e); 2529 2530 old = vq->signalled_used; 2531 new = vq->signalled_used = vq->used_idx; 2532 v = vq->signalled_used_valid; 2533 vq->signalled_used_valid = true; 2534 2535 if (e.flags == VRING_PACKED_EVENT_FLAG_DISABLE) { 2536 return false; 2537 } else if (e.flags == VRING_PACKED_EVENT_FLAG_ENABLE) { 2538 return true; 2539 } 2540 2541 return !v || vring_packed_need_event(vq, vq->used_wrap_counter, 2542 e.off_wrap, new, old); 2543 } 2544 2545 /* Called within rcu_read_lock(). */ 2546 static bool virtio_should_notify(VirtIODevice *vdev, VirtQueue *vq) 2547 { 2548 if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { 2549 return virtio_packed_should_notify(vdev, vq); 2550 } else { 2551 return virtio_split_should_notify(vdev, vq); 2552 } 2553 } 2554 2555 void virtio_notify_irqfd(VirtIODevice *vdev, VirtQueue *vq) 2556 { 2557 WITH_RCU_READ_LOCK_GUARD() { 2558 if (!virtio_should_notify(vdev, vq)) { 2559 return; 2560 } 2561 } 2562 2563 trace_virtio_notify_irqfd(vdev, vq); 2564 2565 /* 2566 * virtio spec 1.0 says ISR bit 0 should be ignored with MSI, but 2567 * windows drivers included in virtio-win 1.8.0 (circa 2015) are 2568 * incorrectly polling this bit during crashdump and hibernation 2569 * in MSI mode, causing a hang if this bit is never updated. 2570 * Recent releases of Windows do not really shut down, but rather 2571 * log out and hibernate to make the next startup faster. Hence, 2572 * this manifested as a more serious hang during shutdown with 2573 * 2574 * Next driver release from 2016 fixed this problem, so working around it 2575 * is not a must, but it's easy to do so let's do it here. 2576 * 2577 * Note: it's safe to update ISR from any thread as it was switched 2578 * to an atomic operation. 2579 */ 2580 virtio_set_isr(vq->vdev, 0x1); 2581 event_notifier_set(&vq->guest_notifier); 2582 } 2583 2584 static void virtio_irq(VirtQueue *vq) 2585 { 2586 virtio_set_isr(vq->vdev, 0x1); 2587 virtio_notify_vector(vq->vdev, vq->vector); 2588 } 2589 2590 void virtio_notify(VirtIODevice *vdev, VirtQueue *vq) 2591 { 2592 WITH_RCU_READ_LOCK_GUARD() { 2593 if (!virtio_should_notify(vdev, vq)) { 2594 return; 2595 } 2596 } 2597 2598 trace_virtio_notify(vdev, vq); 2599 virtio_irq(vq); 2600 } 2601 2602 void virtio_notify_config(VirtIODevice *vdev) 2603 { 2604 if (!(vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) 2605 return; 2606 2607 virtio_set_isr(vdev, 0x3); 2608 vdev->generation++; 2609 virtio_notify_vector(vdev, vdev->config_vector); 2610 } 2611 2612 static bool virtio_device_endian_needed(void *opaque) 2613 { 2614 VirtIODevice *vdev = opaque; 2615 2616 assert(vdev->device_endian != VIRTIO_DEVICE_ENDIAN_UNKNOWN); 2617 if (!virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) { 2618 return vdev->device_endian != virtio_default_endian(); 2619 } 2620 /* Devices conforming to VIRTIO 1.0 or later are always LE. */ 2621 return vdev->device_endian != VIRTIO_DEVICE_ENDIAN_LITTLE; 2622 } 2623 2624 static bool virtio_64bit_features_needed(void *opaque) 2625 { 2626 VirtIODevice *vdev = opaque; 2627 2628 return (vdev->host_features >> 32) != 0; 2629 } 2630 2631 static bool virtio_virtqueue_needed(void *opaque) 2632 { 2633 VirtIODevice *vdev = opaque; 2634 2635 return virtio_host_has_feature(vdev, VIRTIO_F_VERSION_1); 2636 } 2637 2638 static bool virtio_packed_virtqueue_needed(void *opaque) 2639 { 2640 VirtIODevice *vdev = opaque; 2641 2642 return virtio_host_has_feature(vdev, VIRTIO_F_RING_PACKED); 2643 } 2644 2645 static bool virtio_ringsize_needed(void *opaque) 2646 { 2647 VirtIODevice *vdev = opaque; 2648 int i; 2649 2650 for (i = 0; i < VIRTIO_QUEUE_MAX; i++) { 2651 if (vdev->vq[i].vring.num != vdev->vq[i].vring.num_default) { 2652 return true; 2653 } 2654 } 2655 return false; 2656 } 2657 2658 static bool virtio_extra_state_needed(void *opaque) 2659 { 2660 VirtIODevice *vdev = opaque; 2661 BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); 2662 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); 2663 2664 return k->has_extra_state && 2665 k->has_extra_state(qbus->parent); 2666 } 2667 2668 static bool virtio_broken_needed(void *opaque) 2669 { 2670 VirtIODevice *vdev = opaque; 2671 2672 return vdev->broken; 2673 } 2674 2675 static bool virtio_started_needed(void *opaque) 2676 { 2677 VirtIODevice *vdev = opaque; 2678 2679 return vdev->started; 2680 } 2681 2682 static bool virtio_disabled_needed(void *opaque) 2683 { 2684 VirtIODevice *vdev = opaque; 2685 2686 return vdev->disabled; 2687 } 2688 2689 static const VMStateDescription vmstate_virtqueue = { 2690 .name = "virtqueue_state", 2691 .version_id = 1, 2692 .minimum_version_id = 1, 2693 .fields = (VMStateField[]) { 2694 VMSTATE_UINT64(vring.avail, struct VirtQueue), 2695 VMSTATE_UINT64(vring.used, struct VirtQueue), 2696 VMSTATE_END_OF_LIST() 2697 } 2698 }; 2699 2700 static const VMStateDescription vmstate_packed_virtqueue = { 2701 .name = "packed_virtqueue_state", 2702 .version_id = 1, 2703 .minimum_version_id = 1, 2704 .fields = (VMStateField[]) { 2705 VMSTATE_UINT16(last_avail_idx, struct VirtQueue), 2706 VMSTATE_BOOL(last_avail_wrap_counter, struct VirtQueue), 2707 VMSTATE_UINT16(used_idx, struct VirtQueue), 2708 VMSTATE_BOOL(used_wrap_counter, struct VirtQueue), 2709 VMSTATE_UINT32(inuse, struct VirtQueue), 2710 VMSTATE_END_OF_LIST() 2711 } 2712 }; 2713 2714 static const VMStateDescription vmstate_virtio_virtqueues = { 2715 .name = "virtio/virtqueues", 2716 .version_id = 1, 2717 .minimum_version_id = 1, 2718 .needed = &virtio_virtqueue_needed, 2719 .fields = (VMStateField[]) { 2720 VMSTATE_STRUCT_VARRAY_POINTER_KNOWN(vq, struct VirtIODevice, 2721 VIRTIO_QUEUE_MAX, 0, vmstate_virtqueue, VirtQueue), 2722 VMSTATE_END_OF_LIST() 2723 } 2724 }; 2725 2726 static const VMStateDescription vmstate_virtio_packed_virtqueues = { 2727 .name = "virtio/packed_virtqueues", 2728 .version_id = 1, 2729 .minimum_version_id = 1, 2730 .needed = &virtio_packed_virtqueue_needed, 2731 .fields = (VMStateField[]) { 2732 VMSTATE_STRUCT_VARRAY_POINTER_KNOWN(vq, struct VirtIODevice, 2733 VIRTIO_QUEUE_MAX, 0, vmstate_packed_virtqueue, VirtQueue), 2734 VMSTATE_END_OF_LIST() 2735 } 2736 }; 2737 2738 static const VMStateDescription vmstate_ringsize = { 2739 .name = "ringsize_state", 2740 .version_id = 1, 2741 .minimum_version_id = 1, 2742 .fields = (VMStateField[]) { 2743 VMSTATE_UINT32(vring.num_default, struct VirtQueue), 2744 VMSTATE_END_OF_LIST() 2745 } 2746 }; 2747 2748 static const VMStateDescription vmstate_virtio_ringsize = { 2749 .name = "virtio/ringsize", 2750 .version_id = 1, 2751 .minimum_version_id = 1, 2752 .needed = &virtio_ringsize_needed, 2753 .fields = (VMStateField[]) { 2754 VMSTATE_STRUCT_VARRAY_POINTER_KNOWN(vq, struct VirtIODevice, 2755 VIRTIO_QUEUE_MAX, 0, vmstate_ringsize, VirtQueue), 2756 VMSTATE_END_OF_LIST() 2757 } 2758 }; 2759 2760 static int get_extra_state(QEMUFile *f, void *pv, size_t size, 2761 const VMStateField *field) 2762 { 2763 VirtIODevice *vdev = pv; 2764 BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); 2765 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); 2766 2767 if (!k->load_extra_state) { 2768 return -1; 2769 } else { 2770 return k->load_extra_state(qbus->parent, f); 2771 } 2772 } 2773 2774 static int put_extra_state(QEMUFile *f, void *pv, size_t size, 2775 const VMStateField *field, JSONWriter *vmdesc) 2776 { 2777 VirtIODevice *vdev = pv; 2778 BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); 2779 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); 2780 2781 k->save_extra_state(qbus->parent, f); 2782 return 0; 2783 } 2784 2785 static const VMStateInfo vmstate_info_extra_state = { 2786 .name = "virtqueue_extra_state", 2787 .get = get_extra_state, 2788 .put = put_extra_state, 2789 }; 2790 2791 static const VMStateDescription vmstate_virtio_extra_state = { 2792 .name = "virtio/extra_state", 2793 .version_id = 1, 2794 .minimum_version_id = 1, 2795 .needed = &virtio_extra_state_needed, 2796 .fields = (VMStateField[]) { 2797 { 2798 .name = "extra_state", 2799 .version_id = 0, 2800 .field_exists = NULL, 2801 .size = 0, 2802 .info = &vmstate_info_extra_state, 2803 .flags = VMS_SINGLE, 2804 .offset = 0, 2805 }, 2806 VMSTATE_END_OF_LIST() 2807 } 2808 }; 2809 2810 static const VMStateDescription vmstate_virtio_device_endian = { 2811 .name = "virtio/device_endian", 2812 .version_id = 1, 2813 .minimum_version_id = 1, 2814 .needed = &virtio_device_endian_needed, 2815 .fields = (VMStateField[]) { 2816 VMSTATE_UINT8(device_endian, VirtIODevice), 2817 VMSTATE_END_OF_LIST() 2818 } 2819 }; 2820 2821 static const VMStateDescription vmstate_virtio_64bit_features = { 2822 .name = "virtio/64bit_features", 2823 .version_id = 1, 2824 .minimum_version_id = 1, 2825 .needed = &virtio_64bit_features_needed, 2826 .fields = (VMStateField[]) { 2827 VMSTATE_UINT64(guest_features, VirtIODevice), 2828 VMSTATE_END_OF_LIST() 2829 } 2830 }; 2831 2832 static const VMStateDescription vmstate_virtio_broken = { 2833 .name = "virtio/broken", 2834 .version_id = 1, 2835 .minimum_version_id = 1, 2836 .needed = &virtio_broken_needed, 2837 .fields = (VMStateField[]) { 2838 VMSTATE_BOOL(broken, VirtIODevice), 2839 VMSTATE_END_OF_LIST() 2840 } 2841 }; 2842 2843 static const VMStateDescription vmstate_virtio_started = { 2844 .name = "virtio/started", 2845 .version_id = 1, 2846 .minimum_version_id = 1, 2847 .needed = &virtio_started_needed, 2848 .fields = (VMStateField[]) { 2849 VMSTATE_BOOL(started, VirtIODevice), 2850 VMSTATE_END_OF_LIST() 2851 } 2852 }; 2853 2854 static const VMStateDescription vmstate_virtio_disabled = { 2855 .name = "virtio/disabled", 2856 .version_id = 1, 2857 .minimum_version_id = 1, 2858 .needed = &virtio_disabled_needed, 2859 .fields = (VMStateField[]) { 2860 VMSTATE_BOOL(disabled, VirtIODevice), 2861 VMSTATE_END_OF_LIST() 2862 } 2863 }; 2864 2865 static const VMStateDescription vmstate_virtio = { 2866 .name = "virtio", 2867 .version_id = 1, 2868 .minimum_version_id = 1, 2869 .fields = (VMStateField[]) { 2870 VMSTATE_END_OF_LIST() 2871 }, 2872 .subsections = (const VMStateDescription*[]) { 2873 &vmstate_virtio_device_endian, 2874 &vmstate_virtio_64bit_features, 2875 &vmstate_virtio_virtqueues, 2876 &vmstate_virtio_ringsize, 2877 &vmstate_virtio_broken, 2878 &vmstate_virtio_extra_state, 2879 &vmstate_virtio_started, 2880 &vmstate_virtio_packed_virtqueues, 2881 &vmstate_virtio_disabled, 2882 NULL 2883 } 2884 }; 2885 2886 int virtio_save(VirtIODevice *vdev, QEMUFile *f) 2887 { 2888 BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); 2889 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); 2890 VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev); 2891 uint32_t guest_features_lo = (vdev->guest_features & 0xffffffff); 2892 int i; 2893 2894 if (k->save_config) { 2895 k->save_config(qbus->parent, f); 2896 } 2897 2898 qemu_put_8s(f, &vdev->status); 2899 qemu_put_8s(f, &vdev->isr); 2900 qemu_put_be16s(f, &vdev->queue_sel); 2901 qemu_put_be32s(f, &guest_features_lo); 2902 qemu_put_be32(f, vdev->config_len); 2903 qemu_put_buffer(f, vdev->config, vdev->config_len); 2904 2905 for (i = 0; i < VIRTIO_QUEUE_MAX; i++) { 2906 if (vdev->vq[i].vring.num == 0) 2907 break; 2908 } 2909 2910 qemu_put_be32(f, i); 2911 2912 for (i = 0; i < VIRTIO_QUEUE_MAX; i++) { 2913 if (vdev->vq[i].vring.num == 0) 2914 break; 2915 2916 qemu_put_be32(f, vdev->vq[i].vring.num); 2917 if (k->has_variable_vring_alignment) { 2918 qemu_put_be32(f, vdev->vq[i].vring.align); 2919 } 2920 /* 2921 * Save desc now, the rest of the ring addresses are saved in 2922 * subsections for VIRTIO-1 devices. 2923 */ 2924 qemu_put_be64(f, vdev->vq[i].vring.desc); 2925 qemu_put_be16s(f, &vdev->vq[i].last_avail_idx); 2926 if (k->save_queue) { 2927 k->save_queue(qbus->parent, i, f); 2928 } 2929 } 2930 2931 if (vdc->save != NULL) { 2932 vdc->save(vdev, f); 2933 } 2934 2935 if (vdc->vmsd) { 2936 int ret = vmstate_save_state(f, vdc->vmsd, vdev, NULL); 2937 if (ret) { 2938 return ret; 2939 } 2940 } 2941 2942 /* Subsections */ 2943 return vmstate_save_state(f, &vmstate_virtio, vdev, NULL); 2944 } 2945 2946 /* A wrapper for use as a VMState .put function */ 2947 static int virtio_device_put(QEMUFile *f, void *opaque, size_t size, 2948 const VMStateField *field, JSONWriter *vmdesc) 2949 { 2950 return virtio_save(VIRTIO_DEVICE(opaque), f); 2951 } 2952 2953 /* A wrapper for use as a VMState .get function */ 2954 static int virtio_device_get(QEMUFile *f, void *opaque, size_t size, 2955 const VMStateField *field) 2956 { 2957 VirtIODevice *vdev = VIRTIO_DEVICE(opaque); 2958 DeviceClass *dc = DEVICE_CLASS(VIRTIO_DEVICE_GET_CLASS(vdev)); 2959 2960 return virtio_load(vdev, f, dc->vmsd->version_id); 2961 } 2962 2963 const VMStateInfo virtio_vmstate_info = { 2964 .name = "virtio", 2965 .get = virtio_device_get, 2966 .put = virtio_device_put, 2967 }; 2968 2969 static int virtio_set_features_nocheck(VirtIODevice *vdev, uint64_t val) 2970 { 2971 VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); 2972 bool bad = (val & ~(vdev->host_features)) != 0; 2973 2974 val &= vdev->host_features; 2975 if (k->set_features) { 2976 k->set_features(vdev, val); 2977 } 2978 vdev->guest_features = val; 2979 return bad ? -1 : 0; 2980 } 2981 2982 int virtio_set_features(VirtIODevice *vdev, uint64_t val) 2983 { 2984 int ret; 2985 /* 2986 * The driver must not attempt to set features after feature negotiation 2987 * has finished. 2988 */ 2989 if (vdev->status & VIRTIO_CONFIG_S_FEATURES_OK) { 2990 return -EINVAL; 2991 } 2992 2993 if (val & (1ull << VIRTIO_F_BAD_FEATURE)) { 2994 qemu_log_mask(LOG_GUEST_ERROR, 2995 "%s: guest driver for %s has enabled UNUSED(30) feature bit!\n", 2996 __func__, vdev->name); 2997 } 2998 2999 ret = virtio_set_features_nocheck(vdev, val); 3000 if (virtio_vdev_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX)) { 3001 /* VIRTIO_RING_F_EVENT_IDX changes the size of the caches. */ 3002 int i; 3003 for (i = 0; i < VIRTIO_QUEUE_MAX; i++) { 3004 if (vdev->vq[i].vring.num != 0) { 3005 virtio_init_region_cache(vdev, i); 3006 } 3007 } 3008 } 3009 if (!ret) { 3010 if (!virtio_device_started(vdev, vdev->status) && 3011 !virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) { 3012 vdev->start_on_kick = true; 3013 } 3014 } 3015 return ret; 3016 } 3017 3018 size_t virtio_get_config_size(const VirtIOConfigSizeParams *params, 3019 uint64_t host_features) 3020 { 3021 size_t config_size = params->min_size; 3022 const VirtIOFeature *feature_sizes = params->feature_sizes; 3023 size_t i; 3024 3025 for (i = 0; feature_sizes[i].flags != 0; i++) { 3026 if (host_features & feature_sizes[i].flags) { 3027 config_size = MAX(feature_sizes[i].end, config_size); 3028 } 3029 } 3030 3031 assert(config_size <= params->max_size); 3032 return config_size; 3033 } 3034 3035 int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id) 3036 { 3037 int i, ret; 3038 int32_t config_len; 3039 uint32_t num; 3040 uint32_t features; 3041 BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); 3042 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); 3043 VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev); 3044 3045 /* 3046 * We poison the endianness to ensure it does not get used before 3047 * subsections have been loaded. 3048 */ 3049 vdev->device_endian = VIRTIO_DEVICE_ENDIAN_UNKNOWN; 3050 3051 if (k->load_config) { 3052 ret = k->load_config(qbus->parent, f); 3053 if (ret) 3054 return ret; 3055 } 3056 3057 qemu_get_8s(f, &vdev->status); 3058 qemu_get_8s(f, &vdev->isr); 3059 qemu_get_be16s(f, &vdev->queue_sel); 3060 if (vdev->queue_sel >= VIRTIO_QUEUE_MAX) { 3061 return -1; 3062 } 3063 qemu_get_be32s(f, &features); 3064 3065 /* 3066 * Temporarily set guest_features low bits - needed by 3067 * virtio net load code testing for VIRTIO_NET_F_CTRL_GUEST_OFFLOADS 3068 * VIRTIO_NET_F_GUEST_ANNOUNCE and VIRTIO_NET_F_CTRL_VQ. 3069 * 3070 * Note: devices should always test host features in future - don't create 3071 * new dependencies like this. 3072 */ 3073 vdev->guest_features = features; 3074 3075 config_len = qemu_get_be32(f); 3076 3077 /* 3078 * There are cases where the incoming config can be bigger or smaller 3079 * than what we have; so load what we have space for, and skip 3080 * any excess that's in the stream. 3081 */ 3082 qemu_get_buffer(f, vdev->config, MIN(config_len, vdev->config_len)); 3083 3084 while (config_len > vdev->config_len) { 3085 qemu_get_byte(f); 3086 config_len--; 3087 } 3088 3089 num = qemu_get_be32(f); 3090 3091 if (num > VIRTIO_QUEUE_MAX) { 3092 error_report("Invalid number of virtqueues: 0x%x", num); 3093 return -1; 3094 } 3095 3096 for (i = 0; i < num; i++) { 3097 vdev->vq[i].vring.num = qemu_get_be32(f); 3098 if (k->has_variable_vring_alignment) { 3099 vdev->vq[i].vring.align = qemu_get_be32(f); 3100 } 3101 vdev->vq[i].vring.desc = qemu_get_be64(f); 3102 qemu_get_be16s(f, &vdev->vq[i].last_avail_idx); 3103 vdev->vq[i].signalled_used_valid = false; 3104 vdev->vq[i].notification = true; 3105 3106 if (!vdev->vq[i].vring.desc && vdev->vq[i].last_avail_idx) { 3107 error_report("VQ %d address 0x0 " 3108 "inconsistent with Host index 0x%x", 3109 i, vdev->vq[i].last_avail_idx); 3110 return -1; 3111 } 3112 if (k->load_queue) { 3113 ret = k->load_queue(qbus->parent, i, f); 3114 if (ret) 3115 return ret; 3116 } 3117 } 3118 3119 virtio_notify_vector(vdev, VIRTIO_NO_VECTOR); 3120 3121 if (vdc->load != NULL) { 3122 ret = vdc->load(vdev, f, version_id); 3123 if (ret) { 3124 return ret; 3125 } 3126 } 3127 3128 if (vdc->vmsd) { 3129 ret = vmstate_load_state(f, vdc->vmsd, vdev, version_id); 3130 if (ret) { 3131 return ret; 3132 } 3133 } 3134 3135 /* Subsections */ 3136 ret = vmstate_load_state(f, &vmstate_virtio, vdev, 1); 3137 if (ret) { 3138 return ret; 3139 } 3140 3141 if (vdev->device_endian == VIRTIO_DEVICE_ENDIAN_UNKNOWN) { 3142 vdev->device_endian = virtio_default_endian(); 3143 } 3144 3145 if (virtio_64bit_features_needed(vdev)) { 3146 /* 3147 * Subsection load filled vdev->guest_features. Run them 3148 * through virtio_set_features to sanity-check them against 3149 * host_features. 3150 */ 3151 uint64_t features64 = vdev->guest_features; 3152 if (virtio_set_features_nocheck(vdev, features64) < 0) { 3153 error_report("Features 0x%" PRIx64 " unsupported. " 3154 "Allowed features: 0x%" PRIx64, 3155 features64, vdev->host_features); 3156 return -1; 3157 } 3158 } else { 3159 if (virtio_set_features_nocheck(vdev, features) < 0) { 3160 error_report("Features 0x%x unsupported. " 3161 "Allowed features: 0x%" PRIx64, 3162 features, vdev->host_features); 3163 return -1; 3164 } 3165 } 3166 3167 if (!virtio_device_started(vdev, vdev->status) && 3168 !virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) { 3169 vdev->start_on_kick = true; 3170 } 3171 3172 RCU_READ_LOCK_GUARD(); 3173 for (i = 0; i < num; i++) { 3174 if (vdev->vq[i].vring.desc) { 3175 uint16_t nheads; 3176 3177 /* 3178 * VIRTIO-1 devices migrate desc, used, and avail ring addresses so 3179 * only the region cache needs to be set up. Legacy devices need 3180 * to calculate used and avail ring addresses based on the desc 3181 * address. 3182 */ 3183 if (virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) { 3184 virtio_init_region_cache(vdev, i); 3185 } else { 3186 virtio_queue_update_rings(vdev, i); 3187 } 3188 3189 if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { 3190 vdev->vq[i].shadow_avail_idx = vdev->vq[i].last_avail_idx; 3191 vdev->vq[i].shadow_avail_wrap_counter = 3192 vdev->vq[i].last_avail_wrap_counter; 3193 continue; 3194 } 3195 3196 nheads = vring_avail_idx(&vdev->vq[i]) - vdev->vq[i].last_avail_idx; 3197 /* Check it isn't doing strange things with descriptor numbers. */ 3198 if (nheads > vdev->vq[i].vring.num) { 3199 virtio_error(vdev, "VQ %d size 0x%x Guest index 0x%x " 3200 "inconsistent with Host index 0x%x: delta 0x%x", 3201 i, vdev->vq[i].vring.num, 3202 vring_avail_idx(&vdev->vq[i]), 3203 vdev->vq[i].last_avail_idx, nheads); 3204 vdev->vq[i].used_idx = 0; 3205 vdev->vq[i].shadow_avail_idx = 0; 3206 vdev->vq[i].inuse = 0; 3207 continue; 3208 } 3209 vdev->vq[i].used_idx = vring_used_idx(&vdev->vq[i]); 3210 vdev->vq[i].shadow_avail_idx = vring_avail_idx(&vdev->vq[i]); 3211 3212 /* 3213 * Some devices migrate VirtQueueElements that have been popped 3214 * from the avail ring but not yet returned to the used ring. 3215 * Since max ring size < UINT16_MAX it's safe to use modulo 3216 * UINT16_MAX + 1 subtraction. 3217 */ 3218 vdev->vq[i].inuse = (uint16_t)(vdev->vq[i].last_avail_idx - 3219 vdev->vq[i].used_idx); 3220 if (vdev->vq[i].inuse > vdev->vq[i].vring.num) { 3221 error_report("VQ %d size 0x%x < last_avail_idx 0x%x - " 3222 "used_idx 0x%x", 3223 i, vdev->vq[i].vring.num, 3224 vdev->vq[i].last_avail_idx, 3225 vdev->vq[i].used_idx); 3226 return -1; 3227 } 3228 } 3229 } 3230 3231 if (vdc->post_load) { 3232 ret = vdc->post_load(vdev); 3233 if (ret) { 3234 return ret; 3235 } 3236 } 3237 3238 return 0; 3239 } 3240 3241 void virtio_cleanup(VirtIODevice *vdev) 3242 { 3243 qemu_del_vm_change_state_handler(vdev->vmstate); 3244 } 3245 3246 static void virtio_vmstate_change(void *opaque, bool running, RunState state) 3247 { 3248 VirtIODevice *vdev = opaque; 3249 BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); 3250 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); 3251 bool backend_run = running && virtio_device_started(vdev, vdev->status); 3252 vdev->vm_running = running; 3253 3254 if (backend_run) { 3255 virtio_set_status(vdev, vdev->status); 3256 } 3257 3258 if (k->vmstate_change) { 3259 k->vmstate_change(qbus->parent, backend_run); 3260 } 3261 3262 if (!backend_run) { 3263 virtio_set_status(vdev, vdev->status); 3264 } 3265 } 3266 3267 void virtio_instance_init_common(Object *proxy_obj, void *data, 3268 size_t vdev_size, const char *vdev_name) 3269 { 3270 DeviceState *vdev = data; 3271 3272 object_initialize_child_with_props(proxy_obj, "virtio-backend", vdev, 3273 vdev_size, vdev_name, &error_abort, 3274 NULL); 3275 qdev_alias_all_properties(vdev, proxy_obj); 3276 } 3277 3278 void virtio_init(VirtIODevice *vdev, uint16_t device_id, size_t config_size) 3279 { 3280 BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); 3281 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); 3282 int i; 3283 int nvectors = k->query_nvectors ? k->query_nvectors(qbus->parent) : 0; 3284 3285 if (nvectors) { 3286 vdev->vector_queues = 3287 g_malloc0(sizeof(*vdev->vector_queues) * nvectors); 3288 } 3289 3290 vdev->start_on_kick = false; 3291 vdev->started = false; 3292 vdev->vhost_started = false; 3293 vdev->device_id = device_id; 3294 vdev->status = 0; 3295 qatomic_set(&vdev->isr, 0); 3296 vdev->queue_sel = 0; 3297 vdev->config_vector = VIRTIO_NO_VECTOR; 3298 vdev->vq = g_new0(VirtQueue, VIRTIO_QUEUE_MAX); 3299 vdev->vm_running = runstate_is_running(); 3300 vdev->broken = false; 3301 for (i = 0; i < VIRTIO_QUEUE_MAX; i++) { 3302 vdev->vq[i].vector = VIRTIO_NO_VECTOR; 3303 vdev->vq[i].vdev = vdev; 3304 vdev->vq[i].queue_index = i; 3305 vdev->vq[i].host_notifier_enabled = false; 3306 } 3307 3308 vdev->name = virtio_id_to_name(device_id); 3309 vdev->config_len = config_size; 3310 if (vdev->config_len) { 3311 vdev->config = g_malloc0(config_size); 3312 } else { 3313 vdev->config = NULL; 3314 } 3315 vdev->vmstate = qdev_add_vm_change_state_handler(DEVICE(vdev), 3316 virtio_vmstate_change, vdev); 3317 vdev->device_endian = virtio_default_endian(); 3318 vdev->use_guest_notifier_mask = true; 3319 } 3320 3321 /* 3322 * Only devices that have already been around prior to defining the virtio 3323 * standard support legacy mode; this includes devices not specified in the 3324 * standard. All newer devices conform to the virtio standard only. 3325 */ 3326 bool virtio_legacy_allowed(VirtIODevice *vdev) 3327 { 3328 switch (vdev->device_id) { 3329 case VIRTIO_ID_NET: 3330 case VIRTIO_ID_BLOCK: 3331 case VIRTIO_ID_CONSOLE: 3332 case VIRTIO_ID_RNG: 3333 case VIRTIO_ID_BALLOON: 3334 case VIRTIO_ID_RPMSG: 3335 case VIRTIO_ID_SCSI: 3336 case VIRTIO_ID_9P: 3337 case VIRTIO_ID_RPROC_SERIAL: 3338 case VIRTIO_ID_CAIF: 3339 return true; 3340 default: 3341 return false; 3342 } 3343 } 3344 3345 bool virtio_legacy_check_disabled(VirtIODevice *vdev) 3346 { 3347 return vdev->disable_legacy_check; 3348 } 3349 3350 hwaddr virtio_queue_get_desc_addr(VirtIODevice *vdev, int n) 3351 { 3352 return vdev->vq[n].vring.desc; 3353 } 3354 3355 bool virtio_queue_enabled_legacy(VirtIODevice *vdev, int n) 3356 { 3357 return virtio_queue_get_desc_addr(vdev, n) != 0; 3358 } 3359 3360 bool virtio_queue_enabled(VirtIODevice *vdev, int n) 3361 { 3362 BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); 3363 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); 3364 3365 if (k->queue_enabled) { 3366 return k->queue_enabled(qbus->parent, n); 3367 } 3368 return virtio_queue_enabled_legacy(vdev, n); 3369 } 3370 3371 hwaddr virtio_queue_get_avail_addr(VirtIODevice *vdev, int n) 3372 { 3373 return vdev->vq[n].vring.avail; 3374 } 3375 3376 hwaddr virtio_queue_get_used_addr(VirtIODevice *vdev, int n) 3377 { 3378 return vdev->vq[n].vring.used; 3379 } 3380 3381 hwaddr virtio_queue_get_desc_size(VirtIODevice *vdev, int n) 3382 { 3383 return sizeof(VRingDesc) * vdev->vq[n].vring.num; 3384 } 3385 3386 hwaddr virtio_queue_get_avail_size(VirtIODevice *vdev, int n) 3387 { 3388 int s; 3389 3390 if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { 3391 return sizeof(struct VRingPackedDescEvent); 3392 } 3393 3394 s = virtio_vdev_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; 3395 return offsetof(VRingAvail, ring) + 3396 sizeof(uint16_t) * vdev->vq[n].vring.num + s; 3397 } 3398 3399 hwaddr virtio_queue_get_used_size(VirtIODevice *vdev, int n) 3400 { 3401 int s; 3402 3403 if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { 3404 return sizeof(struct VRingPackedDescEvent); 3405 } 3406 3407 s = virtio_vdev_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; 3408 return offsetof(VRingUsed, ring) + 3409 sizeof(VRingUsedElem) * vdev->vq[n].vring.num + s; 3410 } 3411 3412 static unsigned int virtio_queue_packed_get_last_avail_idx(VirtIODevice *vdev, 3413 int n) 3414 { 3415 unsigned int avail, used; 3416 3417 avail = vdev->vq[n].last_avail_idx; 3418 avail |= ((uint16_t)vdev->vq[n].last_avail_wrap_counter) << 15; 3419 3420 used = vdev->vq[n].used_idx; 3421 used |= ((uint16_t)vdev->vq[n].used_wrap_counter) << 15; 3422 3423 return avail | used << 16; 3424 } 3425 3426 static uint16_t virtio_queue_split_get_last_avail_idx(VirtIODevice *vdev, 3427 int n) 3428 { 3429 return vdev->vq[n].last_avail_idx; 3430 } 3431 3432 unsigned int virtio_queue_get_last_avail_idx(VirtIODevice *vdev, int n) 3433 { 3434 if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { 3435 return virtio_queue_packed_get_last_avail_idx(vdev, n); 3436 } else { 3437 return virtio_queue_split_get_last_avail_idx(vdev, n); 3438 } 3439 } 3440 3441 static void virtio_queue_packed_set_last_avail_idx(VirtIODevice *vdev, 3442 int n, unsigned int idx) 3443 { 3444 struct VirtQueue *vq = &vdev->vq[n]; 3445 3446 vq->last_avail_idx = vq->shadow_avail_idx = idx & 0x7fff; 3447 vq->last_avail_wrap_counter = 3448 vq->shadow_avail_wrap_counter = !!(idx & 0x8000); 3449 idx >>= 16; 3450 vq->used_idx = idx & 0x7ffff; 3451 vq->used_wrap_counter = !!(idx & 0x8000); 3452 } 3453 3454 static void virtio_queue_split_set_last_avail_idx(VirtIODevice *vdev, 3455 int n, unsigned int idx) 3456 { 3457 vdev->vq[n].last_avail_idx = idx; 3458 vdev->vq[n].shadow_avail_idx = idx; 3459 } 3460 3461 void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, 3462 unsigned int idx) 3463 { 3464 if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { 3465 virtio_queue_packed_set_last_avail_idx(vdev, n, idx); 3466 } else { 3467 virtio_queue_split_set_last_avail_idx(vdev, n, idx); 3468 } 3469 } 3470 3471 static void virtio_queue_packed_restore_last_avail_idx(VirtIODevice *vdev, 3472 int n) 3473 { 3474 /* We don't have a reference like avail idx in shared memory */ 3475 return; 3476 } 3477 3478 static void virtio_queue_split_restore_last_avail_idx(VirtIODevice *vdev, 3479 int n) 3480 { 3481 RCU_READ_LOCK_GUARD(); 3482 if (vdev->vq[n].vring.desc) { 3483 vdev->vq[n].last_avail_idx = vring_used_idx(&vdev->vq[n]); 3484 vdev->vq[n].shadow_avail_idx = vdev->vq[n].last_avail_idx; 3485 } 3486 } 3487 3488 void virtio_queue_restore_last_avail_idx(VirtIODevice *vdev, int n) 3489 { 3490 if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { 3491 virtio_queue_packed_restore_last_avail_idx(vdev, n); 3492 } else { 3493 virtio_queue_split_restore_last_avail_idx(vdev, n); 3494 } 3495 } 3496 3497 static void virtio_queue_packed_update_used_idx(VirtIODevice *vdev, int n) 3498 { 3499 /* used idx was updated through set_last_avail_idx() */ 3500 return; 3501 } 3502 3503 static void virtio_split_packed_update_used_idx(VirtIODevice *vdev, int n) 3504 { 3505 RCU_READ_LOCK_GUARD(); 3506 if (vdev->vq[n].vring.desc) { 3507 vdev->vq[n].used_idx = vring_used_idx(&vdev->vq[n]); 3508 } 3509 } 3510 3511 void virtio_queue_update_used_idx(VirtIODevice *vdev, int n) 3512 { 3513 if (virtio_vdev_has_feature(vdev, VIRTIO_F_RING_PACKED)) { 3514 return virtio_queue_packed_update_used_idx(vdev, n); 3515 } else { 3516 return virtio_split_packed_update_used_idx(vdev, n); 3517 } 3518 } 3519 3520 void virtio_queue_invalidate_signalled_used(VirtIODevice *vdev, int n) 3521 { 3522 vdev->vq[n].signalled_used_valid = false; 3523 } 3524 3525 VirtQueue *virtio_get_queue(VirtIODevice *vdev, int n) 3526 { 3527 return vdev->vq + n; 3528 } 3529 3530 uint16_t virtio_get_queue_index(VirtQueue *vq) 3531 { 3532 return vq->queue_index; 3533 } 3534 3535 static void virtio_queue_guest_notifier_read(EventNotifier *n) 3536 { 3537 VirtQueue *vq = container_of(n, VirtQueue, guest_notifier); 3538 if (event_notifier_test_and_clear(n)) { 3539 virtio_irq(vq); 3540 } 3541 } 3542 3543 void virtio_queue_set_guest_notifier_fd_handler(VirtQueue *vq, bool assign, 3544 bool with_irqfd) 3545 { 3546 if (assign && !with_irqfd) { 3547 event_notifier_set_handler(&vq->guest_notifier, 3548 virtio_queue_guest_notifier_read); 3549 } else { 3550 event_notifier_set_handler(&vq->guest_notifier, NULL); 3551 } 3552 if (!assign) { 3553 /* Test and clear notifier before closing it, 3554 * in case poll callback didn't have time to run. */ 3555 virtio_queue_guest_notifier_read(&vq->guest_notifier); 3556 } 3557 } 3558 3559 EventNotifier *virtio_queue_get_guest_notifier(VirtQueue *vq) 3560 { 3561 return &vq->guest_notifier; 3562 } 3563 3564 static void virtio_queue_host_notifier_aio_poll_begin(EventNotifier *n) 3565 { 3566 VirtQueue *vq = container_of(n, VirtQueue, host_notifier); 3567 3568 virtio_queue_set_notification(vq, 0); 3569 } 3570 3571 static bool virtio_queue_host_notifier_aio_poll(void *opaque) 3572 { 3573 EventNotifier *n = opaque; 3574 VirtQueue *vq = container_of(n, VirtQueue, host_notifier); 3575 3576 return vq->vring.desc && !virtio_queue_empty(vq); 3577 } 3578 3579 static void virtio_queue_host_notifier_aio_poll_ready(EventNotifier *n) 3580 { 3581 VirtQueue *vq = container_of(n, VirtQueue, host_notifier); 3582 3583 virtio_queue_notify_vq(vq); 3584 } 3585 3586 static void virtio_queue_host_notifier_aio_poll_end(EventNotifier *n) 3587 { 3588 VirtQueue *vq = container_of(n, VirtQueue, host_notifier); 3589 3590 /* Caller polls once more after this to catch requests that race with us */ 3591 virtio_queue_set_notification(vq, 1); 3592 } 3593 3594 void virtio_queue_aio_attach_host_notifier(VirtQueue *vq, AioContext *ctx) 3595 { 3596 aio_set_event_notifier(ctx, &vq->host_notifier, true, 3597 virtio_queue_host_notifier_read, 3598 virtio_queue_host_notifier_aio_poll, 3599 virtio_queue_host_notifier_aio_poll_ready); 3600 aio_set_event_notifier_poll(ctx, &vq->host_notifier, 3601 virtio_queue_host_notifier_aio_poll_begin, 3602 virtio_queue_host_notifier_aio_poll_end); 3603 } 3604 3605 /* 3606 * Same as virtio_queue_aio_attach_host_notifier() but without polling. Use 3607 * this for rx virtqueues and similar cases where the virtqueue handler 3608 * function does not pop all elements. When the virtqueue is left non-empty 3609 * polling consumes CPU cycles and should not be used. 3610 */ 3611 void virtio_queue_aio_attach_host_notifier_no_poll(VirtQueue *vq, AioContext *ctx) 3612 { 3613 aio_set_event_notifier(ctx, &vq->host_notifier, true, 3614 virtio_queue_host_notifier_read, 3615 NULL, NULL); 3616 } 3617 3618 void virtio_queue_aio_detach_host_notifier(VirtQueue *vq, AioContext *ctx) 3619 { 3620 aio_set_event_notifier(ctx, &vq->host_notifier, true, NULL, NULL, NULL); 3621 /* Test and clear notifier before after disabling event, 3622 * in case poll callback didn't have time to run. */ 3623 virtio_queue_host_notifier_read(&vq->host_notifier); 3624 } 3625 3626 void virtio_queue_host_notifier_read(EventNotifier *n) 3627 { 3628 VirtQueue *vq = container_of(n, VirtQueue, host_notifier); 3629 if (event_notifier_test_and_clear(n)) { 3630 virtio_queue_notify_vq(vq); 3631 } 3632 } 3633 3634 EventNotifier *virtio_queue_get_host_notifier(VirtQueue *vq) 3635 { 3636 return &vq->host_notifier; 3637 } 3638 3639 void virtio_queue_set_host_notifier_enabled(VirtQueue *vq, bool enabled) 3640 { 3641 vq->host_notifier_enabled = enabled; 3642 } 3643 3644 int virtio_queue_set_host_notifier_mr(VirtIODevice *vdev, int n, 3645 MemoryRegion *mr, bool assign) 3646 { 3647 BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); 3648 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); 3649 3650 if (k->set_host_notifier_mr) { 3651 return k->set_host_notifier_mr(qbus->parent, n, mr, assign); 3652 } 3653 3654 return -1; 3655 } 3656 3657 void virtio_device_set_child_bus_name(VirtIODevice *vdev, char *bus_name) 3658 { 3659 g_free(vdev->bus_name); 3660 vdev->bus_name = g_strdup(bus_name); 3661 } 3662 3663 void G_GNUC_PRINTF(2, 3) virtio_error(VirtIODevice *vdev, const char *fmt, ...) 3664 { 3665 va_list ap; 3666 3667 va_start(ap, fmt); 3668 error_vreport(fmt, ap); 3669 va_end(ap); 3670 3671 if (virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) { 3672 vdev->status = vdev->status | VIRTIO_CONFIG_S_NEEDS_RESET; 3673 virtio_notify_config(vdev); 3674 } 3675 3676 vdev->broken = true; 3677 } 3678 3679 static void virtio_memory_listener_commit(MemoryListener *listener) 3680 { 3681 VirtIODevice *vdev = container_of(listener, VirtIODevice, listener); 3682 int i; 3683 3684 for (i = 0; i < VIRTIO_QUEUE_MAX; i++) { 3685 if (vdev->vq[i].vring.num == 0) { 3686 break; 3687 } 3688 virtio_init_region_cache(vdev, i); 3689 } 3690 } 3691 3692 static void virtio_device_realize(DeviceState *dev, Error **errp) 3693 { 3694 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 3695 VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(dev); 3696 Error *err = NULL; 3697 3698 /* Devices should either use vmsd or the load/save methods */ 3699 assert(!vdc->vmsd || !vdc->load); 3700 3701 if (vdc->realize != NULL) { 3702 vdc->realize(dev, &err); 3703 if (err != NULL) { 3704 error_propagate(errp, err); 3705 return; 3706 } 3707 } 3708 3709 virtio_bus_device_plugged(vdev, &err); 3710 if (err != NULL) { 3711 error_propagate(errp, err); 3712 vdc->unrealize(dev); 3713 return; 3714 } 3715 3716 vdev->listener.commit = virtio_memory_listener_commit; 3717 vdev->listener.name = "virtio"; 3718 memory_listener_register(&vdev->listener, vdev->dma_as); 3719 QTAILQ_INSERT_TAIL(&virtio_list, vdev, next); 3720 } 3721 3722 static void virtio_device_unrealize(DeviceState *dev) 3723 { 3724 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 3725 VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(dev); 3726 3727 memory_listener_unregister(&vdev->listener); 3728 virtio_bus_device_unplugged(vdev); 3729 3730 if (vdc->unrealize != NULL) { 3731 vdc->unrealize(dev); 3732 } 3733 3734 QTAILQ_REMOVE(&virtio_list, vdev, next); 3735 g_free(vdev->bus_name); 3736 vdev->bus_name = NULL; 3737 } 3738 3739 static void virtio_device_free_virtqueues(VirtIODevice *vdev) 3740 { 3741 int i; 3742 if (!vdev->vq) { 3743 return; 3744 } 3745 3746 for (i = 0; i < VIRTIO_QUEUE_MAX; i++) { 3747 if (vdev->vq[i].vring.num == 0) { 3748 break; 3749 } 3750 virtio_virtqueue_reset_region_cache(&vdev->vq[i]); 3751 } 3752 g_free(vdev->vq); 3753 } 3754 3755 static void virtio_device_instance_finalize(Object *obj) 3756 { 3757 VirtIODevice *vdev = VIRTIO_DEVICE(obj); 3758 3759 virtio_device_free_virtqueues(vdev); 3760 3761 g_free(vdev->config); 3762 g_free(vdev->vector_queues); 3763 } 3764 3765 static Property virtio_properties[] = { 3766 DEFINE_VIRTIO_COMMON_FEATURES(VirtIODevice, host_features), 3767 DEFINE_PROP_BOOL("use-started", VirtIODevice, use_started, true), 3768 DEFINE_PROP_BOOL("use-disabled-flag", VirtIODevice, use_disabled_flag, true), 3769 DEFINE_PROP_BOOL("x-disable-legacy-check", VirtIODevice, 3770 disable_legacy_check, false), 3771 DEFINE_PROP_END_OF_LIST(), 3772 }; 3773 3774 static int virtio_device_start_ioeventfd_impl(VirtIODevice *vdev) 3775 { 3776 VirtioBusState *qbus = VIRTIO_BUS(qdev_get_parent_bus(DEVICE(vdev))); 3777 int i, n, r, err; 3778 3779 /* 3780 * Batch all the host notifiers in a single transaction to avoid 3781 * quadratic time complexity in address_space_update_ioeventfds(). 3782 */ 3783 memory_region_transaction_begin(); 3784 for (n = 0; n < VIRTIO_QUEUE_MAX; n++) { 3785 VirtQueue *vq = &vdev->vq[n]; 3786 if (!virtio_queue_get_num(vdev, n)) { 3787 continue; 3788 } 3789 r = virtio_bus_set_host_notifier(qbus, n, true); 3790 if (r < 0) { 3791 err = r; 3792 goto assign_error; 3793 } 3794 event_notifier_set_handler(&vq->host_notifier, 3795 virtio_queue_host_notifier_read); 3796 } 3797 3798 for (n = 0; n < VIRTIO_QUEUE_MAX; n++) { 3799 /* Kick right away to begin processing requests already in vring */ 3800 VirtQueue *vq = &vdev->vq[n]; 3801 if (!vq->vring.num) { 3802 continue; 3803 } 3804 event_notifier_set(&vq->host_notifier); 3805 } 3806 memory_region_transaction_commit(); 3807 return 0; 3808 3809 assign_error: 3810 i = n; /* save n for a second iteration after transaction is committed. */ 3811 while (--n >= 0) { 3812 VirtQueue *vq = &vdev->vq[n]; 3813 if (!virtio_queue_get_num(vdev, n)) { 3814 continue; 3815 } 3816 3817 event_notifier_set_handler(&vq->host_notifier, NULL); 3818 r = virtio_bus_set_host_notifier(qbus, n, false); 3819 assert(r >= 0); 3820 } 3821 /* 3822 * The transaction expects the ioeventfds to be open when it 3823 * commits. Do it now, before the cleanup loop. 3824 */ 3825 memory_region_transaction_commit(); 3826 3827 while (--i >= 0) { 3828 if (!virtio_queue_get_num(vdev, i)) { 3829 continue; 3830 } 3831 virtio_bus_cleanup_host_notifier(qbus, i); 3832 } 3833 return err; 3834 } 3835 3836 int virtio_device_start_ioeventfd(VirtIODevice *vdev) 3837 { 3838 BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); 3839 VirtioBusState *vbus = VIRTIO_BUS(qbus); 3840 3841 return virtio_bus_start_ioeventfd(vbus); 3842 } 3843 3844 static void virtio_device_stop_ioeventfd_impl(VirtIODevice *vdev) 3845 { 3846 VirtioBusState *qbus = VIRTIO_BUS(qdev_get_parent_bus(DEVICE(vdev))); 3847 int n, r; 3848 3849 /* 3850 * Batch all the host notifiers in a single transaction to avoid 3851 * quadratic time complexity in address_space_update_ioeventfds(). 3852 */ 3853 memory_region_transaction_begin(); 3854 for (n = 0; n < VIRTIO_QUEUE_MAX; n++) { 3855 VirtQueue *vq = &vdev->vq[n]; 3856 3857 if (!virtio_queue_get_num(vdev, n)) { 3858 continue; 3859 } 3860 event_notifier_set_handler(&vq->host_notifier, NULL); 3861 r = virtio_bus_set_host_notifier(qbus, n, false); 3862 assert(r >= 0); 3863 } 3864 /* 3865 * The transaction expects the ioeventfds to be open when it 3866 * commits. Do it now, before the cleanup loop. 3867 */ 3868 memory_region_transaction_commit(); 3869 3870 for (n = 0; n < VIRTIO_QUEUE_MAX; n++) { 3871 if (!virtio_queue_get_num(vdev, n)) { 3872 continue; 3873 } 3874 virtio_bus_cleanup_host_notifier(qbus, n); 3875 } 3876 } 3877 3878 int virtio_device_grab_ioeventfd(VirtIODevice *vdev) 3879 { 3880 BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); 3881 VirtioBusState *vbus = VIRTIO_BUS(qbus); 3882 3883 return virtio_bus_grab_ioeventfd(vbus); 3884 } 3885 3886 void virtio_device_release_ioeventfd(VirtIODevice *vdev) 3887 { 3888 BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); 3889 VirtioBusState *vbus = VIRTIO_BUS(qbus); 3890 3891 virtio_bus_release_ioeventfd(vbus); 3892 } 3893 3894 static void virtio_device_class_init(ObjectClass *klass, void *data) 3895 { 3896 /* Set the default value here. */ 3897 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); 3898 DeviceClass *dc = DEVICE_CLASS(klass); 3899 3900 dc->realize = virtio_device_realize; 3901 dc->unrealize = virtio_device_unrealize; 3902 dc->bus_type = TYPE_VIRTIO_BUS; 3903 device_class_set_props(dc, virtio_properties); 3904 vdc->start_ioeventfd = virtio_device_start_ioeventfd_impl; 3905 vdc->stop_ioeventfd = virtio_device_stop_ioeventfd_impl; 3906 3907 vdc->legacy_features |= VIRTIO_LEGACY_FEATURES; 3908 3909 QTAILQ_INIT(&virtio_list); 3910 } 3911 3912 bool virtio_device_ioeventfd_enabled(VirtIODevice *vdev) 3913 { 3914 BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); 3915 VirtioBusState *vbus = VIRTIO_BUS(qbus); 3916 3917 return virtio_bus_ioeventfd_enabled(vbus); 3918 } 3919 3920 VirtioInfoList *qmp_x_query_virtio(Error **errp) 3921 { 3922 VirtioInfoList *list = NULL; 3923 VirtioInfoList *node; 3924 VirtIODevice *vdev; 3925 3926 QTAILQ_FOREACH(vdev, &virtio_list, next) { 3927 DeviceState *dev = DEVICE(vdev); 3928 Error *err = NULL; 3929 QObject *obj = qmp_qom_get(dev->canonical_path, "realized", &err); 3930 3931 if (err == NULL) { 3932 GString *is_realized = qobject_to_json_pretty(obj, true); 3933 /* virtio device is NOT realized, remove it from list */ 3934 if (!strncmp(is_realized->str, "false", 4)) { 3935 QTAILQ_REMOVE(&virtio_list, vdev, next); 3936 } else { 3937 node = g_new0(VirtioInfoList, 1); 3938 node->value = g_new(VirtioInfo, 1); 3939 node->value->path = g_strdup(dev->canonical_path); 3940 node->value->name = g_strdup(vdev->name); 3941 QAPI_LIST_PREPEND(list, node->value); 3942 } 3943 g_string_free(is_realized, true); 3944 } 3945 qobject_unref(obj); 3946 } 3947 3948 return list; 3949 } 3950 3951 static const TypeInfo virtio_device_info = { 3952 .name = TYPE_VIRTIO_DEVICE, 3953 .parent = TYPE_DEVICE, 3954 .instance_size = sizeof(VirtIODevice), 3955 .class_init = virtio_device_class_init, 3956 .instance_finalize = virtio_device_instance_finalize, 3957 .abstract = true, 3958 .class_size = sizeof(VirtioDeviceClass), 3959 }; 3960 3961 static void virtio_register_types(void) 3962 { 3963 type_register_static(&virtio_device_info); 3964 } 3965 3966 type_init(virtio_register_types) 3967