1 /* 2 * vhost support 3 * 4 * Copyright Red Hat, Inc. 2010 5 * 6 * Authors: 7 * Michael S. Tsirkin <mst@redhat.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 * Contributions after 2012-01-13 are licensed under the terms of the 13 * GNU GPL, version 2 or (at your option) any later version. 14 */ 15 16 #include "qemu/osdep.h" 17 #include "qapi/error.h" 18 #include "hw/virtio/vhost.h" 19 #include "qemu/atomic.h" 20 #include "qemu/range.h" 21 #include "qemu/error-report.h" 22 #include "qemu/memfd.h" 23 #include "standard-headers/linux/vhost_types.h" 24 #include "exec/address-spaces.h" 25 #include "hw/virtio/virtio-bus.h" 26 #include "hw/virtio/virtio-access.h" 27 #include "migration/blocker.h" 28 #include "migration/qemu-file-types.h" 29 #include "sysemu/dma.h" 30 #include "trace.h" 31 32 /* enabled until disconnected backend stabilizes */ 33 #define _VHOST_DEBUG 1 34 35 #ifdef _VHOST_DEBUG 36 #define VHOST_OPS_DEBUG(fmt, ...) \ 37 do { error_report(fmt ": %s (%d)", ## __VA_ARGS__, \ 38 strerror(errno), errno); } while (0) 39 #else 40 #define VHOST_OPS_DEBUG(fmt, ...) \ 41 do { } while (0) 42 #endif 43 44 static struct vhost_log *vhost_log; 45 static struct vhost_log *vhost_log_shm; 46 47 static unsigned int used_memslots; 48 static QLIST_HEAD(, vhost_dev) vhost_devices = 49 QLIST_HEAD_INITIALIZER(vhost_devices); 50 51 bool vhost_has_free_slot(void) 52 { 53 unsigned int slots_limit = ~0U; 54 struct vhost_dev *hdev; 55 56 QLIST_FOREACH(hdev, &vhost_devices, entry) { 57 unsigned int r = hdev->vhost_ops->vhost_backend_memslots_limit(hdev); 58 slots_limit = MIN(slots_limit, r); 59 } 60 return slots_limit > used_memslots; 61 } 62 63 static void vhost_dev_sync_region(struct vhost_dev *dev, 64 MemoryRegionSection *section, 65 uint64_t mfirst, uint64_t mlast, 66 uint64_t rfirst, uint64_t rlast) 67 { 68 vhost_log_chunk_t *log = dev->log->log; 69 70 uint64_t start = MAX(mfirst, rfirst); 71 uint64_t end = MIN(mlast, rlast); 72 vhost_log_chunk_t *from = log + start / VHOST_LOG_CHUNK; 73 vhost_log_chunk_t *to = log + end / VHOST_LOG_CHUNK + 1; 74 uint64_t addr = QEMU_ALIGN_DOWN(start, VHOST_LOG_CHUNK); 75 76 if (end < start) { 77 return; 78 } 79 assert(end / VHOST_LOG_CHUNK < dev->log_size); 80 assert(start / VHOST_LOG_CHUNK < dev->log_size); 81 82 for (;from < to; ++from) { 83 vhost_log_chunk_t log; 84 /* We first check with non-atomic: much cheaper, 85 * and we expect non-dirty to be the common case. */ 86 if (!*from) { 87 addr += VHOST_LOG_CHUNK; 88 continue; 89 } 90 /* Data must be read atomically. We don't really need barrier semantics 91 * but it's easier to use atomic_* than roll our own. */ 92 log = atomic_xchg(from, 0); 93 while (log) { 94 int bit = ctzl(log); 95 hwaddr page_addr; 96 hwaddr section_offset; 97 hwaddr mr_offset; 98 page_addr = addr + bit * VHOST_LOG_PAGE; 99 section_offset = page_addr - section->offset_within_address_space; 100 mr_offset = section_offset + section->offset_within_region; 101 memory_region_set_dirty(section->mr, mr_offset, VHOST_LOG_PAGE); 102 log &= ~(0x1ull << bit); 103 } 104 addr += VHOST_LOG_CHUNK; 105 } 106 } 107 108 static int vhost_sync_dirty_bitmap(struct vhost_dev *dev, 109 MemoryRegionSection *section, 110 hwaddr first, 111 hwaddr last) 112 { 113 int i; 114 hwaddr start_addr; 115 hwaddr end_addr; 116 117 if (!dev->log_enabled || !dev->started) { 118 return 0; 119 } 120 start_addr = section->offset_within_address_space; 121 end_addr = range_get_last(start_addr, int128_get64(section->size)); 122 start_addr = MAX(first, start_addr); 123 end_addr = MIN(last, end_addr); 124 125 for (i = 0; i < dev->mem->nregions; ++i) { 126 struct vhost_memory_region *reg = dev->mem->regions + i; 127 vhost_dev_sync_region(dev, section, start_addr, end_addr, 128 reg->guest_phys_addr, 129 range_get_last(reg->guest_phys_addr, 130 reg->memory_size)); 131 } 132 for (i = 0; i < dev->nvqs; ++i) { 133 struct vhost_virtqueue *vq = dev->vqs + i; 134 135 if (!vq->used_phys && !vq->used_size) { 136 continue; 137 } 138 139 vhost_dev_sync_region(dev, section, start_addr, end_addr, vq->used_phys, 140 range_get_last(vq->used_phys, vq->used_size)); 141 } 142 return 0; 143 } 144 145 static void vhost_log_sync(MemoryListener *listener, 146 MemoryRegionSection *section) 147 { 148 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 149 memory_listener); 150 vhost_sync_dirty_bitmap(dev, section, 0x0, ~0x0ULL); 151 } 152 153 static void vhost_log_sync_range(struct vhost_dev *dev, 154 hwaddr first, hwaddr last) 155 { 156 int i; 157 /* FIXME: this is N^2 in number of sections */ 158 for (i = 0; i < dev->n_mem_sections; ++i) { 159 MemoryRegionSection *section = &dev->mem_sections[i]; 160 vhost_sync_dirty_bitmap(dev, section, first, last); 161 } 162 } 163 164 static uint64_t vhost_get_log_size(struct vhost_dev *dev) 165 { 166 uint64_t log_size = 0; 167 int i; 168 for (i = 0; i < dev->mem->nregions; ++i) { 169 struct vhost_memory_region *reg = dev->mem->regions + i; 170 uint64_t last = range_get_last(reg->guest_phys_addr, 171 reg->memory_size); 172 log_size = MAX(log_size, last / VHOST_LOG_CHUNK + 1); 173 } 174 for (i = 0; i < dev->nvqs; ++i) { 175 struct vhost_virtqueue *vq = dev->vqs + i; 176 177 if (!vq->used_phys && !vq->used_size) { 178 continue; 179 } 180 181 uint64_t last = vq->used_phys + vq->used_size - 1; 182 log_size = MAX(log_size, last / VHOST_LOG_CHUNK + 1); 183 } 184 return log_size; 185 } 186 187 static struct vhost_log *vhost_log_alloc(uint64_t size, bool share) 188 { 189 Error *err = NULL; 190 struct vhost_log *log; 191 uint64_t logsize = size * sizeof(*(log->log)); 192 int fd = -1; 193 194 log = g_new0(struct vhost_log, 1); 195 if (share) { 196 log->log = qemu_memfd_alloc("vhost-log", logsize, 197 F_SEAL_GROW | F_SEAL_SHRINK | F_SEAL_SEAL, 198 &fd, &err); 199 if (err) { 200 error_report_err(err); 201 g_free(log); 202 return NULL; 203 } 204 memset(log->log, 0, logsize); 205 } else { 206 log->log = g_malloc0(logsize); 207 } 208 209 log->size = size; 210 log->refcnt = 1; 211 log->fd = fd; 212 213 return log; 214 } 215 216 static struct vhost_log *vhost_log_get(uint64_t size, bool share) 217 { 218 struct vhost_log *log = share ? vhost_log_shm : vhost_log; 219 220 if (!log || log->size != size) { 221 log = vhost_log_alloc(size, share); 222 if (share) { 223 vhost_log_shm = log; 224 } else { 225 vhost_log = log; 226 } 227 } else { 228 ++log->refcnt; 229 } 230 231 return log; 232 } 233 234 static void vhost_log_put(struct vhost_dev *dev, bool sync) 235 { 236 struct vhost_log *log = dev->log; 237 238 if (!log) { 239 return; 240 } 241 242 --log->refcnt; 243 if (log->refcnt == 0) { 244 /* Sync only the range covered by the old log */ 245 if (dev->log_size && sync) { 246 vhost_log_sync_range(dev, 0, dev->log_size * VHOST_LOG_CHUNK - 1); 247 } 248 249 if (vhost_log == log) { 250 g_free(log->log); 251 vhost_log = NULL; 252 } else if (vhost_log_shm == log) { 253 qemu_memfd_free(log->log, log->size * sizeof(*(log->log)), 254 log->fd); 255 vhost_log_shm = NULL; 256 } 257 258 g_free(log); 259 } 260 261 dev->log = NULL; 262 dev->log_size = 0; 263 } 264 265 static bool vhost_dev_log_is_shared(struct vhost_dev *dev) 266 { 267 return dev->vhost_ops->vhost_requires_shm_log && 268 dev->vhost_ops->vhost_requires_shm_log(dev); 269 } 270 271 static inline void vhost_dev_log_resize(struct vhost_dev *dev, uint64_t size) 272 { 273 struct vhost_log *log = vhost_log_get(size, vhost_dev_log_is_shared(dev)); 274 uint64_t log_base = (uintptr_t)log->log; 275 int r; 276 277 /* inform backend of log switching, this must be done before 278 releasing the current log, to ensure no logging is lost */ 279 r = dev->vhost_ops->vhost_set_log_base(dev, log_base, log); 280 if (r < 0) { 281 VHOST_OPS_DEBUG("vhost_set_log_base failed"); 282 } 283 284 vhost_log_put(dev, true); 285 dev->log = log; 286 dev->log_size = size; 287 } 288 289 static int vhost_dev_has_iommu(struct vhost_dev *dev) 290 { 291 VirtIODevice *vdev = dev->vdev; 292 293 return virtio_host_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM); 294 } 295 296 static void *vhost_memory_map(struct vhost_dev *dev, hwaddr addr, 297 hwaddr *plen, bool is_write) 298 { 299 if (!vhost_dev_has_iommu(dev)) { 300 return cpu_physical_memory_map(addr, plen, is_write); 301 } else { 302 return (void *)(uintptr_t)addr; 303 } 304 } 305 306 static void vhost_memory_unmap(struct vhost_dev *dev, void *buffer, 307 hwaddr len, int is_write, 308 hwaddr access_len) 309 { 310 if (!vhost_dev_has_iommu(dev)) { 311 cpu_physical_memory_unmap(buffer, len, is_write, access_len); 312 } 313 } 314 315 static int vhost_verify_ring_part_mapping(void *ring_hva, 316 uint64_t ring_gpa, 317 uint64_t ring_size, 318 void *reg_hva, 319 uint64_t reg_gpa, 320 uint64_t reg_size) 321 { 322 uint64_t hva_ring_offset; 323 uint64_t ring_last = range_get_last(ring_gpa, ring_size); 324 uint64_t reg_last = range_get_last(reg_gpa, reg_size); 325 326 if (ring_last < reg_gpa || ring_gpa > reg_last) { 327 return 0; 328 } 329 /* check that whole ring's is mapped */ 330 if (ring_last > reg_last) { 331 return -ENOMEM; 332 } 333 /* check that ring's MemoryRegion wasn't replaced */ 334 hva_ring_offset = ring_gpa - reg_gpa; 335 if (ring_hva != reg_hva + hva_ring_offset) { 336 return -EBUSY; 337 } 338 339 return 0; 340 } 341 342 static int vhost_verify_ring_mappings(struct vhost_dev *dev, 343 void *reg_hva, 344 uint64_t reg_gpa, 345 uint64_t reg_size) 346 { 347 int i, j; 348 int r = 0; 349 const char *part_name[] = { 350 "descriptor table", 351 "available ring", 352 "used ring" 353 }; 354 355 if (vhost_dev_has_iommu(dev)) { 356 return 0; 357 } 358 359 for (i = 0; i < dev->nvqs; ++i) { 360 struct vhost_virtqueue *vq = dev->vqs + i; 361 362 if (vq->desc_phys == 0) { 363 continue; 364 } 365 366 j = 0; 367 r = vhost_verify_ring_part_mapping( 368 vq->desc, vq->desc_phys, vq->desc_size, 369 reg_hva, reg_gpa, reg_size); 370 if (r) { 371 break; 372 } 373 374 j++; 375 r = vhost_verify_ring_part_mapping( 376 vq->avail, vq->avail_phys, vq->avail_size, 377 reg_hva, reg_gpa, reg_size); 378 if (r) { 379 break; 380 } 381 382 j++; 383 r = vhost_verify_ring_part_mapping( 384 vq->used, vq->used_phys, vq->used_size, 385 reg_hva, reg_gpa, reg_size); 386 if (r) { 387 break; 388 } 389 } 390 391 if (r == -ENOMEM) { 392 error_report("Unable to map %s for ring %d", part_name[j], i); 393 } else if (r == -EBUSY) { 394 error_report("%s relocated for ring %d", part_name[j], i); 395 } 396 return r; 397 } 398 399 static bool vhost_section(struct vhost_dev *dev, MemoryRegionSection *section) 400 { 401 bool result; 402 bool log_dirty = memory_region_get_dirty_log_mask(section->mr) & 403 ~(1 << DIRTY_MEMORY_MIGRATION); 404 result = memory_region_is_ram(section->mr) && 405 !memory_region_is_rom(section->mr); 406 407 /* Vhost doesn't handle any block which is doing dirty-tracking other 408 * than migration; this typically fires on VGA areas. 409 */ 410 result &= !log_dirty; 411 412 if (result && dev->vhost_ops->vhost_backend_mem_section_filter) { 413 result &= 414 dev->vhost_ops->vhost_backend_mem_section_filter(dev, section); 415 } 416 417 trace_vhost_section(section->mr->name, result); 418 return result; 419 } 420 421 static void vhost_begin(MemoryListener *listener) 422 { 423 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 424 memory_listener); 425 dev->tmp_sections = NULL; 426 dev->n_tmp_sections = 0; 427 } 428 429 static void vhost_commit(MemoryListener *listener) 430 { 431 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 432 memory_listener); 433 MemoryRegionSection *old_sections; 434 int n_old_sections; 435 uint64_t log_size; 436 size_t regions_size; 437 int r; 438 int i; 439 bool changed = false; 440 441 /* Note we can be called before the device is started, but then 442 * starting the device calls set_mem_table, so we need to have 443 * built the data structures. 444 */ 445 old_sections = dev->mem_sections; 446 n_old_sections = dev->n_mem_sections; 447 dev->mem_sections = dev->tmp_sections; 448 dev->n_mem_sections = dev->n_tmp_sections; 449 450 if (dev->n_mem_sections != n_old_sections) { 451 changed = true; 452 } else { 453 /* Same size, lets check the contents */ 454 for (int i = 0; i < n_old_sections; i++) { 455 if (!MemoryRegionSection_eq(&old_sections[i], 456 &dev->mem_sections[i])) { 457 changed = true; 458 break; 459 } 460 } 461 } 462 463 trace_vhost_commit(dev->started, changed); 464 if (!changed) { 465 goto out; 466 } 467 468 /* Rebuild the regions list from the new sections list */ 469 regions_size = offsetof(struct vhost_memory, regions) + 470 dev->n_mem_sections * sizeof dev->mem->regions[0]; 471 dev->mem = g_realloc(dev->mem, regions_size); 472 dev->mem->nregions = dev->n_mem_sections; 473 used_memslots = dev->mem->nregions; 474 for (i = 0; i < dev->n_mem_sections; i++) { 475 struct vhost_memory_region *cur_vmr = dev->mem->regions + i; 476 struct MemoryRegionSection *mrs = dev->mem_sections + i; 477 478 cur_vmr->guest_phys_addr = mrs->offset_within_address_space; 479 cur_vmr->memory_size = int128_get64(mrs->size); 480 cur_vmr->userspace_addr = 481 (uintptr_t)memory_region_get_ram_ptr(mrs->mr) + 482 mrs->offset_within_region; 483 cur_vmr->flags_padding = 0; 484 } 485 486 if (!dev->started) { 487 goto out; 488 } 489 490 for (i = 0; i < dev->mem->nregions; i++) { 491 if (vhost_verify_ring_mappings(dev, 492 (void *)(uintptr_t)dev->mem->regions[i].userspace_addr, 493 dev->mem->regions[i].guest_phys_addr, 494 dev->mem->regions[i].memory_size)) { 495 error_report("Verify ring failure on region %d", i); 496 abort(); 497 } 498 } 499 500 if (!dev->log_enabled) { 501 r = dev->vhost_ops->vhost_set_mem_table(dev, dev->mem); 502 if (r < 0) { 503 VHOST_OPS_DEBUG("vhost_set_mem_table failed"); 504 } 505 goto out; 506 } 507 log_size = vhost_get_log_size(dev); 508 /* We allocate an extra 4K bytes to log, 509 * to reduce the * number of reallocations. */ 510 #define VHOST_LOG_BUFFER (0x1000 / sizeof *dev->log) 511 /* To log more, must increase log size before table update. */ 512 if (dev->log_size < log_size) { 513 vhost_dev_log_resize(dev, log_size + VHOST_LOG_BUFFER); 514 } 515 r = dev->vhost_ops->vhost_set_mem_table(dev, dev->mem); 516 if (r < 0) { 517 VHOST_OPS_DEBUG("vhost_set_mem_table failed"); 518 } 519 /* To log less, can only decrease log size after table update. */ 520 if (dev->log_size > log_size + VHOST_LOG_BUFFER) { 521 vhost_dev_log_resize(dev, log_size); 522 } 523 524 out: 525 /* Deref the old list of sections, this must happen _after_ the 526 * vhost_set_mem_table to ensure the client isn't still using the 527 * section we're about to unref. 528 */ 529 while (n_old_sections--) { 530 memory_region_unref(old_sections[n_old_sections].mr); 531 } 532 g_free(old_sections); 533 return; 534 } 535 536 /* Adds the section data to the tmp_section structure. 537 * It relies on the listener calling us in memory address order 538 * and for each region (via the _add and _nop methods) to 539 * join neighbours. 540 */ 541 static void vhost_region_add_section(struct vhost_dev *dev, 542 MemoryRegionSection *section) 543 { 544 bool need_add = true; 545 uint64_t mrs_size = int128_get64(section->size); 546 uint64_t mrs_gpa = section->offset_within_address_space; 547 uintptr_t mrs_host = (uintptr_t)memory_region_get_ram_ptr(section->mr) + 548 section->offset_within_region; 549 RAMBlock *mrs_rb = section->mr->ram_block; 550 551 trace_vhost_region_add_section(section->mr->name, mrs_gpa, mrs_size, 552 mrs_host); 553 554 if (dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER) { 555 /* Round the section to it's page size */ 556 /* First align the start down to a page boundary */ 557 size_t mrs_page = qemu_ram_pagesize(mrs_rb); 558 uint64_t alignage = mrs_host & (mrs_page - 1); 559 if (alignage) { 560 mrs_host -= alignage; 561 mrs_size += alignage; 562 mrs_gpa -= alignage; 563 } 564 /* Now align the size up to a page boundary */ 565 alignage = mrs_size & (mrs_page - 1); 566 if (alignage) { 567 mrs_size += mrs_page - alignage; 568 } 569 trace_vhost_region_add_section_aligned(section->mr->name, mrs_gpa, 570 mrs_size, mrs_host); 571 } 572 573 if (dev->n_tmp_sections) { 574 /* Since we already have at least one section, lets see if 575 * this extends it; since we're scanning in order, we only 576 * have to look at the last one, and the FlatView that calls 577 * us shouldn't have overlaps. 578 */ 579 MemoryRegionSection *prev_sec = dev->tmp_sections + 580 (dev->n_tmp_sections - 1); 581 uint64_t prev_gpa_start = prev_sec->offset_within_address_space; 582 uint64_t prev_size = int128_get64(prev_sec->size); 583 uint64_t prev_gpa_end = range_get_last(prev_gpa_start, prev_size); 584 uint64_t prev_host_start = 585 (uintptr_t)memory_region_get_ram_ptr(prev_sec->mr) + 586 prev_sec->offset_within_region; 587 uint64_t prev_host_end = range_get_last(prev_host_start, prev_size); 588 589 if (mrs_gpa <= (prev_gpa_end + 1)) { 590 /* OK, looks like overlapping/intersecting - it's possible that 591 * the rounding to page sizes has made them overlap, but they should 592 * match up in the same RAMBlock if they do. 593 */ 594 if (mrs_gpa < prev_gpa_start) { 595 error_report("%s:Section '%s' rounded to %"PRIx64 596 " prior to previous '%s' %"PRIx64, 597 __func__, section->mr->name, mrs_gpa, 598 prev_sec->mr->name, prev_gpa_start); 599 /* A way to cleanly fail here would be better */ 600 return; 601 } 602 /* Offset from the start of the previous GPA to this GPA */ 603 size_t offset = mrs_gpa - prev_gpa_start; 604 605 if (prev_host_start + offset == mrs_host && 606 section->mr == prev_sec->mr && 607 (!dev->vhost_ops->vhost_backend_can_merge || 608 dev->vhost_ops->vhost_backend_can_merge(dev, 609 mrs_host, mrs_size, 610 prev_host_start, prev_size))) { 611 uint64_t max_end = MAX(prev_host_end, mrs_host + mrs_size); 612 need_add = false; 613 prev_sec->offset_within_address_space = 614 MIN(prev_gpa_start, mrs_gpa); 615 prev_sec->offset_within_region = 616 MIN(prev_host_start, mrs_host) - 617 (uintptr_t)memory_region_get_ram_ptr(prev_sec->mr); 618 prev_sec->size = int128_make64(max_end - MIN(prev_host_start, 619 mrs_host)); 620 trace_vhost_region_add_section_merge(section->mr->name, 621 int128_get64(prev_sec->size), 622 prev_sec->offset_within_address_space, 623 prev_sec->offset_within_region); 624 } else { 625 /* adjoining regions are fine, but overlapping ones with 626 * different blocks/offsets shouldn't happen 627 */ 628 if (mrs_gpa != prev_gpa_end + 1) { 629 error_report("%s: Overlapping but not coherent sections " 630 "at %"PRIx64, 631 __func__, mrs_gpa); 632 return; 633 } 634 } 635 } 636 } 637 638 if (need_add) { 639 ++dev->n_tmp_sections; 640 dev->tmp_sections = g_renew(MemoryRegionSection, dev->tmp_sections, 641 dev->n_tmp_sections); 642 dev->tmp_sections[dev->n_tmp_sections - 1] = *section; 643 /* The flatview isn't stable and we don't use it, making it NULL 644 * means we can memcmp the list. 645 */ 646 dev->tmp_sections[dev->n_tmp_sections - 1].fv = NULL; 647 memory_region_ref(section->mr); 648 } 649 } 650 651 /* Used for both add and nop callbacks */ 652 static void vhost_region_addnop(MemoryListener *listener, 653 MemoryRegionSection *section) 654 { 655 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 656 memory_listener); 657 658 if (!vhost_section(dev, section)) { 659 return; 660 } 661 vhost_region_add_section(dev, section); 662 } 663 664 static void vhost_iommu_unmap_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb) 665 { 666 struct vhost_iommu *iommu = container_of(n, struct vhost_iommu, n); 667 struct vhost_dev *hdev = iommu->hdev; 668 hwaddr iova = iotlb->iova + iommu->iommu_offset; 669 670 if (vhost_backend_invalidate_device_iotlb(hdev, iova, 671 iotlb->addr_mask + 1)) { 672 error_report("Fail to invalidate device iotlb"); 673 } 674 } 675 676 static void vhost_iommu_region_add(MemoryListener *listener, 677 MemoryRegionSection *section) 678 { 679 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 680 iommu_listener); 681 struct vhost_iommu *iommu; 682 Int128 end; 683 int iommu_idx, ret; 684 IOMMUMemoryRegion *iommu_mr; 685 Error *err = NULL; 686 687 if (!memory_region_is_iommu(section->mr)) { 688 return; 689 } 690 691 iommu_mr = IOMMU_MEMORY_REGION(section->mr); 692 693 iommu = g_malloc0(sizeof(*iommu)); 694 end = int128_add(int128_make64(section->offset_within_region), 695 section->size); 696 end = int128_sub(end, int128_one()); 697 iommu_idx = memory_region_iommu_attrs_to_index(iommu_mr, 698 MEMTXATTRS_UNSPECIFIED); 699 iommu_notifier_init(&iommu->n, vhost_iommu_unmap_notify, 700 IOMMU_NOTIFIER_UNMAP, 701 section->offset_within_region, 702 int128_get64(end), 703 iommu_idx); 704 iommu->mr = section->mr; 705 iommu->iommu_offset = section->offset_within_address_space - 706 section->offset_within_region; 707 iommu->hdev = dev; 708 ret = memory_region_register_iommu_notifier(section->mr, &iommu->n, &err); 709 if (ret) { 710 error_report_err(err); 711 exit(1); 712 } 713 QLIST_INSERT_HEAD(&dev->iommu_list, iommu, iommu_next); 714 /* TODO: can replay help performance here? */ 715 } 716 717 static void vhost_iommu_region_del(MemoryListener *listener, 718 MemoryRegionSection *section) 719 { 720 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 721 iommu_listener); 722 struct vhost_iommu *iommu; 723 724 if (!memory_region_is_iommu(section->mr)) { 725 return; 726 } 727 728 QLIST_FOREACH(iommu, &dev->iommu_list, iommu_next) { 729 if (iommu->mr == section->mr && 730 iommu->n.start == section->offset_within_region) { 731 memory_region_unregister_iommu_notifier(iommu->mr, 732 &iommu->n); 733 QLIST_REMOVE(iommu, iommu_next); 734 g_free(iommu); 735 break; 736 } 737 } 738 } 739 740 static int vhost_virtqueue_set_addr(struct vhost_dev *dev, 741 struct vhost_virtqueue *vq, 742 unsigned idx, bool enable_log) 743 { 744 struct vhost_vring_addr addr = { 745 .index = idx, 746 .desc_user_addr = (uint64_t)(unsigned long)vq->desc, 747 .avail_user_addr = (uint64_t)(unsigned long)vq->avail, 748 .used_user_addr = (uint64_t)(unsigned long)vq->used, 749 .log_guest_addr = vq->used_phys, 750 .flags = enable_log ? (1 << VHOST_VRING_F_LOG) : 0, 751 }; 752 int r = dev->vhost_ops->vhost_set_vring_addr(dev, &addr); 753 if (r < 0) { 754 VHOST_OPS_DEBUG("vhost_set_vring_addr failed"); 755 return -errno; 756 } 757 return 0; 758 } 759 760 static int vhost_dev_set_features(struct vhost_dev *dev, 761 bool enable_log) 762 { 763 uint64_t features = dev->acked_features; 764 int r; 765 if (enable_log) { 766 features |= 0x1ULL << VHOST_F_LOG_ALL; 767 } 768 r = dev->vhost_ops->vhost_set_features(dev, features); 769 if (r < 0) { 770 VHOST_OPS_DEBUG("vhost_set_features failed"); 771 } 772 return r < 0 ? -errno : 0; 773 } 774 775 static int vhost_dev_set_log(struct vhost_dev *dev, bool enable_log) 776 { 777 int r, i, idx; 778 r = vhost_dev_set_features(dev, enable_log); 779 if (r < 0) { 780 goto err_features; 781 } 782 for (i = 0; i < dev->nvqs; ++i) { 783 idx = dev->vhost_ops->vhost_get_vq_index(dev, dev->vq_index + i); 784 r = vhost_virtqueue_set_addr(dev, dev->vqs + i, idx, 785 enable_log); 786 if (r < 0) { 787 goto err_vq; 788 } 789 } 790 return 0; 791 err_vq: 792 for (; i >= 0; --i) { 793 idx = dev->vhost_ops->vhost_get_vq_index(dev, dev->vq_index + i); 794 vhost_virtqueue_set_addr(dev, dev->vqs + i, idx, 795 dev->log_enabled); 796 } 797 vhost_dev_set_features(dev, dev->log_enabled); 798 err_features: 799 return r; 800 } 801 802 static int vhost_migration_log(MemoryListener *listener, int enable) 803 { 804 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 805 memory_listener); 806 int r; 807 if (!!enable == dev->log_enabled) { 808 return 0; 809 } 810 if (!dev->started) { 811 dev->log_enabled = enable; 812 return 0; 813 } 814 if (!enable) { 815 r = vhost_dev_set_log(dev, false); 816 if (r < 0) { 817 return r; 818 } 819 vhost_log_put(dev, false); 820 } else { 821 vhost_dev_log_resize(dev, vhost_get_log_size(dev)); 822 r = vhost_dev_set_log(dev, true); 823 if (r < 0) { 824 return r; 825 } 826 } 827 dev->log_enabled = enable; 828 return 0; 829 } 830 831 static void vhost_log_global_start(MemoryListener *listener) 832 { 833 int r; 834 835 r = vhost_migration_log(listener, true); 836 if (r < 0) { 837 abort(); 838 } 839 } 840 841 static void vhost_log_global_stop(MemoryListener *listener) 842 { 843 int r; 844 845 r = vhost_migration_log(listener, false); 846 if (r < 0) { 847 abort(); 848 } 849 } 850 851 static void vhost_log_start(MemoryListener *listener, 852 MemoryRegionSection *section, 853 int old, int new) 854 { 855 /* FIXME: implement */ 856 } 857 858 static void vhost_log_stop(MemoryListener *listener, 859 MemoryRegionSection *section, 860 int old, int new) 861 { 862 /* FIXME: implement */ 863 } 864 865 /* The vhost driver natively knows how to handle the vrings of non 866 * cross-endian legacy devices and modern devices. Only legacy devices 867 * exposed to a bi-endian guest may require the vhost driver to use a 868 * specific endianness. 869 */ 870 static inline bool vhost_needs_vring_endian(VirtIODevice *vdev) 871 { 872 if (virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) { 873 return false; 874 } 875 #ifdef HOST_WORDS_BIGENDIAN 876 return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_LITTLE; 877 #else 878 return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG; 879 #endif 880 } 881 882 static int vhost_virtqueue_set_vring_endian_legacy(struct vhost_dev *dev, 883 bool is_big_endian, 884 int vhost_vq_index) 885 { 886 struct vhost_vring_state s = { 887 .index = vhost_vq_index, 888 .num = is_big_endian 889 }; 890 891 if (!dev->vhost_ops->vhost_set_vring_endian(dev, &s)) { 892 return 0; 893 } 894 895 VHOST_OPS_DEBUG("vhost_set_vring_endian failed"); 896 if (errno == ENOTTY) { 897 error_report("vhost does not support cross-endian"); 898 return -ENOSYS; 899 } 900 901 return -errno; 902 } 903 904 static int vhost_memory_region_lookup(struct vhost_dev *hdev, 905 uint64_t gpa, uint64_t *uaddr, 906 uint64_t *len) 907 { 908 int i; 909 910 for (i = 0; i < hdev->mem->nregions; i++) { 911 struct vhost_memory_region *reg = hdev->mem->regions + i; 912 913 if (gpa >= reg->guest_phys_addr && 914 reg->guest_phys_addr + reg->memory_size > gpa) { 915 *uaddr = reg->userspace_addr + gpa - reg->guest_phys_addr; 916 *len = reg->guest_phys_addr + reg->memory_size - gpa; 917 return 0; 918 } 919 } 920 921 return -EFAULT; 922 } 923 924 int vhost_device_iotlb_miss(struct vhost_dev *dev, uint64_t iova, int write) 925 { 926 IOMMUTLBEntry iotlb; 927 uint64_t uaddr, len; 928 int ret = -EFAULT; 929 930 RCU_READ_LOCK_GUARD(); 931 932 trace_vhost_iotlb_miss(dev, 1); 933 934 iotlb = address_space_get_iotlb_entry(dev->vdev->dma_as, 935 iova, write, 936 MEMTXATTRS_UNSPECIFIED); 937 if (iotlb.target_as != NULL) { 938 ret = vhost_memory_region_lookup(dev, iotlb.translated_addr, 939 &uaddr, &len); 940 if (ret) { 941 trace_vhost_iotlb_miss(dev, 3); 942 error_report("Fail to lookup the translated address " 943 "%"PRIx64, iotlb.translated_addr); 944 goto out; 945 } 946 947 len = MIN(iotlb.addr_mask + 1, len); 948 iova = iova & ~iotlb.addr_mask; 949 950 ret = vhost_backend_update_device_iotlb(dev, iova, uaddr, 951 len, iotlb.perm); 952 if (ret) { 953 trace_vhost_iotlb_miss(dev, 4); 954 error_report("Fail to update device iotlb"); 955 goto out; 956 } 957 } 958 959 trace_vhost_iotlb_miss(dev, 2); 960 961 out: 962 return ret; 963 } 964 965 static int vhost_virtqueue_start(struct vhost_dev *dev, 966 struct VirtIODevice *vdev, 967 struct vhost_virtqueue *vq, 968 unsigned idx) 969 { 970 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); 971 VirtioBusState *vbus = VIRTIO_BUS(qbus); 972 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(vbus); 973 hwaddr s, l, a; 974 int r; 975 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, idx); 976 struct vhost_vring_file file = { 977 .index = vhost_vq_index 978 }; 979 struct vhost_vring_state state = { 980 .index = vhost_vq_index 981 }; 982 struct VirtQueue *vvq = virtio_get_queue(vdev, idx); 983 984 a = virtio_queue_get_desc_addr(vdev, idx); 985 if (a == 0) { 986 /* Queue might not be ready for start */ 987 return 0; 988 } 989 990 vq->num = state.num = virtio_queue_get_num(vdev, idx); 991 r = dev->vhost_ops->vhost_set_vring_num(dev, &state); 992 if (r) { 993 VHOST_OPS_DEBUG("vhost_set_vring_num failed"); 994 return -errno; 995 } 996 997 state.num = virtio_queue_get_last_avail_idx(vdev, idx); 998 r = dev->vhost_ops->vhost_set_vring_base(dev, &state); 999 if (r) { 1000 VHOST_OPS_DEBUG("vhost_set_vring_base failed"); 1001 return -errno; 1002 } 1003 1004 if (vhost_needs_vring_endian(vdev)) { 1005 r = vhost_virtqueue_set_vring_endian_legacy(dev, 1006 virtio_is_big_endian(vdev), 1007 vhost_vq_index); 1008 if (r) { 1009 return -errno; 1010 } 1011 } 1012 1013 vq->desc_size = s = l = virtio_queue_get_desc_size(vdev, idx); 1014 vq->desc_phys = a; 1015 vq->desc = vhost_memory_map(dev, a, &l, false); 1016 if (!vq->desc || l != s) { 1017 r = -ENOMEM; 1018 goto fail_alloc_desc; 1019 } 1020 vq->avail_size = s = l = virtio_queue_get_avail_size(vdev, idx); 1021 vq->avail_phys = a = virtio_queue_get_avail_addr(vdev, idx); 1022 vq->avail = vhost_memory_map(dev, a, &l, false); 1023 if (!vq->avail || l != s) { 1024 r = -ENOMEM; 1025 goto fail_alloc_avail; 1026 } 1027 vq->used_size = s = l = virtio_queue_get_used_size(vdev, idx); 1028 vq->used_phys = a = virtio_queue_get_used_addr(vdev, idx); 1029 vq->used = vhost_memory_map(dev, a, &l, true); 1030 if (!vq->used || l != s) { 1031 r = -ENOMEM; 1032 goto fail_alloc_used; 1033 } 1034 1035 r = vhost_virtqueue_set_addr(dev, vq, vhost_vq_index, dev->log_enabled); 1036 if (r < 0) { 1037 r = -errno; 1038 goto fail_alloc; 1039 } 1040 1041 file.fd = event_notifier_get_fd(virtio_queue_get_host_notifier(vvq)); 1042 r = dev->vhost_ops->vhost_set_vring_kick(dev, &file); 1043 if (r) { 1044 VHOST_OPS_DEBUG("vhost_set_vring_kick failed"); 1045 r = -errno; 1046 goto fail_kick; 1047 } 1048 1049 /* Clear and discard previous events if any. */ 1050 event_notifier_test_and_clear(&vq->masked_notifier); 1051 1052 /* Init vring in unmasked state, unless guest_notifier_mask 1053 * will do it later. 1054 */ 1055 if (!vdev->use_guest_notifier_mask) { 1056 /* TODO: check and handle errors. */ 1057 vhost_virtqueue_mask(dev, vdev, idx, false); 1058 } 1059 1060 if (k->query_guest_notifiers && 1061 k->query_guest_notifiers(qbus->parent) && 1062 virtio_queue_vector(vdev, idx) == VIRTIO_NO_VECTOR) { 1063 file.fd = -1; 1064 r = dev->vhost_ops->vhost_set_vring_call(dev, &file); 1065 if (r) { 1066 goto fail_vector; 1067 } 1068 } 1069 1070 return 0; 1071 1072 fail_vector: 1073 fail_kick: 1074 fail_alloc: 1075 vhost_memory_unmap(dev, vq->used, virtio_queue_get_used_size(vdev, idx), 1076 0, 0); 1077 fail_alloc_used: 1078 vhost_memory_unmap(dev, vq->avail, virtio_queue_get_avail_size(vdev, idx), 1079 0, 0); 1080 fail_alloc_avail: 1081 vhost_memory_unmap(dev, vq->desc, virtio_queue_get_desc_size(vdev, idx), 1082 0, 0); 1083 fail_alloc_desc: 1084 return r; 1085 } 1086 1087 static void vhost_virtqueue_stop(struct vhost_dev *dev, 1088 struct VirtIODevice *vdev, 1089 struct vhost_virtqueue *vq, 1090 unsigned idx) 1091 { 1092 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, idx); 1093 struct vhost_vring_state state = { 1094 .index = vhost_vq_index, 1095 }; 1096 int r; 1097 1098 if (virtio_queue_get_desc_addr(vdev, idx) == 0) { 1099 /* Don't stop the virtqueue which might have not been started */ 1100 return; 1101 } 1102 1103 r = dev->vhost_ops->vhost_get_vring_base(dev, &state); 1104 if (r < 0) { 1105 VHOST_OPS_DEBUG("vhost VQ %u ring restore failed: %d", idx, r); 1106 /* Connection to the backend is broken, so let's sync internal 1107 * last avail idx to the device used idx. 1108 */ 1109 virtio_queue_restore_last_avail_idx(vdev, idx); 1110 } else { 1111 virtio_queue_set_last_avail_idx(vdev, idx, state.num); 1112 } 1113 virtio_queue_invalidate_signalled_used(vdev, idx); 1114 virtio_queue_update_used_idx(vdev, idx); 1115 1116 /* In the cross-endian case, we need to reset the vring endianness to 1117 * native as legacy devices expect so by default. 1118 */ 1119 if (vhost_needs_vring_endian(vdev)) { 1120 vhost_virtqueue_set_vring_endian_legacy(dev, 1121 !virtio_is_big_endian(vdev), 1122 vhost_vq_index); 1123 } 1124 1125 vhost_memory_unmap(dev, vq->used, virtio_queue_get_used_size(vdev, idx), 1126 1, virtio_queue_get_used_size(vdev, idx)); 1127 vhost_memory_unmap(dev, vq->avail, virtio_queue_get_avail_size(vdev, idx), 1128 0, virtio_queue_get_avail_size(vdev, idx)); 1129 vhost_memory_unmap(dev, vq->desc, virtio_queue_get_desc_size(vdev, idx), 1130 0, virtio_queue_get_desc_size(vdev, idx)); 1131 } 1132 1133 static void vhost_eventfd_add(MemoryListener *listener, 1134 MemoryRegionSection *section, 1135 bool match_data, uint64_t data, EventNotifier *e) 1136 { 1137 } 1138 1139 static void vhost_eventfd_del(MemoryListener *listener, 1140 MemoryRegionSection *section, 1141 bool match_data, uint64_t data, EventNotifier *e) 1142 { 1143 } 1144 1145 static int vhost_virtqueue_set_busyloop_timeout(struct vhost_dev *dev, 1146 int n, uint32_t timeout) 1147 { 1148 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, n); 1149 struct vhost_vring_state state = { 1150 .index = vhost_vq_index, 1151 .num = timeout, 1152 }; 1153 int r; 1154 1155 if (!dev->vhost_ops->vhost_set_vring_busyloop_timeout) { 1156 return -EINVAL; 1157 } 1158 1159 r = dev->vhost_ops->vhost_set_vring_busyloop_timeout(dev, &state); 1160 if (r) { 1161 VHOST_OPS_DEBUG("vhost_set_vring_busyloop_timeout failed"); 1162 return r; 1163 } 1164 1165 return 0; 1166 } 1167 1168 static int vhost_virtqueue_init(struct vhost_dev *dev, 1169 struct vhost_virtqueue *vq, int n) 1170 { 1171 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, n); 1172 struct vhost_vring_file file = { 1173 .index = vhost_vq_index, 1174 }; 1175 int r = event_notifier_init(&vq->masked_notifier, 0); 1176 if (r < 0) { 1177 return r; 1178 } 1179 1180 file.fd = event_notifier_get_fd(&vq->masked_notifier); 1181 r = dev->vhost_ops->vhost_set_vring_call(dev, &file); 1182 if (r) { 1183 VHOST_OPS_DEBUG("vhost_set_vring_call failed"); 1184 r = -errno; 1185 goto fail_call; 1186 } 1187 1188 vq->dev = dev; 1189 1190 return 0; 1191 fail_call: 1192 event_notifier_cleanup(&vq->masked_notifier); 1193 return r; 1194 } 1195 1196 static void vhost_virtqueue_cleanup(struct vhost_virtqueue *vq) 1197 { 1198 event_notifier_cleanup(&vq->masked_notifier); 1199 } 1200 1201 int vhost_dev_init(struct vhost_dev *hdev, void *opaque, 1202 VhostBackendType backend_type, uint32_t busyloop_timeout) 1203 { 1204 uint64_t features; 1205 int i, r, n_initialized_vqs = 0; 1206 Error *local_err = NULL; 1207 1208 hdev->vdev = NULL; 1209 hdev->migration_blocker = NULL; 1210 1211 r = vhost_set_backend_type(hdev, backend_type); 1212 assert(r >= 0); 1213 1214 r = hdev->vhost_ops->vhost_backend_init(hdev, opaque); 1215 if (r < 0) { 1216 goto fail; 1217 } 1218 1219 r = hdev->vhost_ops->vhost_set_owner(hdev); 1220 if (r < 0) { 1221 VHOST_OPS_DEBUG("vhost_set_owner failed"); 1222 goto fail; 1223 } 1224 1225 r = hdev->vhost_ops->vhost_get_features(hdev, &features); 1226 if (r < 0) { 1227 VHOST_OPS_DEBUG("vhost_get_features failed"); 1228 goto fail; 1229 } 1230 1231 for (i = 0; i < hdev->nvqs; ++i, ++n_initialized_vqs) { 1232 r = vhost_virtqueue_init(hdev, hdev->vqs + i, hdev->vq_index + i); 1233 if (r < 0) { 1234 goto fail; 1235 } 1236 } 1237 1238 if (busyloop_timeout) { 1239 for (i = 0; i < hdev->nvqs; ++i) { 1240 r = vhost_virtqueue_set_busyloop_timeout(hdev, hdev->vq_index + i, 1241 busyloop_timeout); 1242 if (r < 0) { 1243 goto fail_busyloop; 1244 } 1245 } 1246 } 1247 1248 hdev->features = features; 1249 1250 hdev->memory_listener = (MemoryListener) { 1251 .begin = vhost_begin, 1252 .commit = vhost_commit, 1253 .region_add = vhost_region_addnop, 1254 .region_nop = vhost_region_addnop, 1255 .log_start = vhost_log_start, 1256 .log_stop = vhost_log_stop, 1257 .log_sync = vhost_log_sync, 1258 .log_global_start = vhost_log_global_start, 1259 .log_global_stop = vhost_log_global_stop, 1260 .eventfd_add = vhost_eventfd_add, 1261 .eventfd_del = vhost_eventfd_del, 1262 .priority = 10 1263 }; 1264 1265 hdev->iommu_listener = (MemoryListener) { 1266 .region_add = vhost_iommu_region_add, 1267 .region_del = vhost_iommu_region_del, 1268 }; 1269 1270 if (hdev->migration_blocker == NULL) { 1271 if (!(hdev->features & (0x1ULL << VHOST_F_LOG_ALL))) { 1272 error_setg(&hdev->migration_blocker, 1273 "Migration disabled: vhost lacks VHOST_F_LOG_ALL feature."); 1274 } else if (vhost_dev_log_is_shared(hdev) && !qemu_memfd_alloc_check()) { 1275 error_setg(&hdev->migration_blocker, 1276 "Migration disabled: failed to allocate shared memory"); 1277 } 1278 } 1279 1280 if (hdev->migration_blocker != NULL) { 1281 r = migrate_add_blocker(hdev->migration_blocker, &local_err); 1282 if (local_err) { 1283 error_report_err(local_err); 1284 error_free(hdev->migration_blocker); 1285 goto fail_busyloop; 1286 } 1287 } 1288 1289 hdev->mem = g_malloc0(offsetof(struct vhost_memory, regions)); 1290 hdev->n_mem_sections = 0; 1291 hdev->mem_sections = NULL; 1292 hdev->log = NULL; 1293 hdev->log_size = 0; 1294 hdev->log_enabled = false; 1295 hdev->started = false; 1296 memory_listener_register(&hdev->memory_listener, &address_space_memory); 1297 QLIST_INSERT_HEAD(&vhost_devices, hdev, entry); 1298 1299 if (used_memslots > hdev->vhost_ops->vhost_backend_memslots_limit(hdev)) { 1300 error_report("vhost backend memory slots limit is less" 1301 " than current number of present memory slots"); 1302 r = -1; 1303 if (busyloop_timeout) { 1304 goto fail_busyloop; 1305 } else { 1306 goto fail; 1307 } 1308 } 1309 1310 return 0; 1311 1312 fail_busyloop: 1313 while (--i >= 0) { 1314 vhost_virtqueue_set_busyloop_timeout(hdev, hdev->vq_index + i, 0); 1315 } 1316 fail: 1317 hdev->nvqs = n_initialized_vqs; 1318 vhost_dev_cleanup(hdev); 1319 return r; 1320 } 1321 1322 void vhost_dev_cleanup(struct vhost_dev *hdev) 1323 { 1324 int i; 1325 1326 for (i = 0; i < hdev->nvqs; ++i) { 1327 vhost_virtqueue_cleanup(hdev->vqs + i); 1328 } 1329 if (hdev->mem) { 1330 /* those are only safe after successful init */ 1331 memory_listener_unregister(&hdev->memory_listener); 1332 QLIST_REMOVE(hdev, entry); 1333 } 1334 if (hdev->migration_blocker) { 1335 migrate_del_blocker(hdev->migration_blocker); 1336 error_free(hdev->migration_blocker); 1337 } 1338 g_free(hdev->mem); 1339 g_free(hdev->mem_sections); 1340 if (hdev->vhost_ops) { 1341 hdev->vhost_ops->vhost_backend_cleanup(hdev); 1342 } 1343 assert(!hdev->log); 1344 1345 memset(hdev, 0, sizeof(struct vhost_dev)); 1346 } 1347 1348 /* Stop processing guest IO notifications in qemu. 1349 * Start processing them in vhost in kernel. 1350 */ 1351 int vhost_dev_enable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev) 1352 { 1353 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); 1354 int i, r, e; 1355 1356 /* We will pass the notifiers to the kernel, make sure that QEMU 1357 * doesn't interfere. 1358 */ 1359 r = virtio_device_grab_ioeventfd(vdev); 1360 if (r < 0) { 1361 error_report("binding does not support host notifiers"); 1362 goto fail; 1363 } 1364 1365 for (i = 0; i < hdev->nvqs; ++i) { 1366 r = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i, 1367 true); 1368 if (r < 0) { 1369 error_report("vhost VQ %d notifier binding failed: %d", i, -r); 1370 goto fail_vq; 1371 } 1372 } 1373 1374 return 0; 1375 fail_vq: 1376 while (--i >= 0) { 1377 e = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i, 1378 false); 1379 if (e < 0) { 1380 error_report("vhost VQ %d notifier cleanup error: %d", i, -r); 1381 } 1382 assert (e >= 0); 1383 virtio_bus_cleanup_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i); 1384 } 1385 virtio_device_release_ioeventfd(vdev); 1386 fail: 1387 return r; 1388 } 1389 1390 /* Stop processing guest IO notifications in vhost. 1391 * Start processing them in qemu. 1392 * This might actually run the qemu handlers right away, 1393 * so virtio in qemu must be completely setup when this is called. 1394 */ 1395 void vhost_dev_disable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev) 1396 { 1397 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); 1398 int i, r; 1399 1400 for (i = 0; i < hdev->nvqs; ++i) { 1401 r = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i, 1402 false); 1403 if (r < 0) { 1404 error_report("vhost VQ %d notifier cleanup failed: %d", i, -r); 1405 } 1406 assert (r >= 0); 1407 virtio_bus_cleanup_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i); 1408 } 1409 virtio_device_release_ioeventfd(vdev); 1410 } 1411 1412 /* Test and clear event pending status. 1413 * Should be called after unmask to avoid losing events. 1414 */ 1415 bool vhost_virtqueue_pending(struct vhost_dev *hdev, int n) 1416 { 1417 struct vhost_virtqueue *vq = hdev->vqs + n - hdev->vq_index; 1418 assert(n >= hdev->vq_index && n < hdev->vq_index + hdev->nvqs); 1419 return event_notifier_test_and_clear(&vq->masked_notifier); 1420 } 1421 1422 /* Mask/unmask events from this vq. */ 1423 void vhost_virtqueue_mask(struct vhost_dev *hdev, VirtIODevice *vdev, int n, 1424 bool mask) 1425 { 1426 struct VirtQueue *vvq = virtio_get_queue(vdev, n); 1427 int r, index = n - hdev->vq_index; 1428 struct vhost_vring_file file; 1429 1430 /* should only be called after backend is connected */ 1431 assert(hdev->vhost_ops); 1432 1433 if (mask) { 1434 assert(vdev->use_guest_notifier_mask); 1435 file.fd = event_notifier_get_fd(&hdev->vqs[index].masked_notifier); 1436 } else { 1437 file.fd = event_notifier_get_fd(virtio_queue_get_guest_notifier(vvq)); 1438 } 1439 1440 file.index = hdev->vhost_ops->vhost_get_vq_index(hdev, n); 1441 r = hdev->vhost_ops->vhost_set_vring_call(hdev, &file); 1442 if (r < 0) { 1443 VHOST_OPS_DEBUG("vhost_set_vring_call failed"); 1444 } 1445 } 1446 1447 uint64_t vhost_get_features(struct vhost_dev *hdev, const int *feature_bits, 1448 uint64_t features) 1449 { 1450 const int *bit = feature_bits; 1451 while (*bit != VHOST_INVALID_FEATURE_BIT) { 1452 uint64_t bit_mask = (1ULL << *bit); 1453 if (!(hdev->features & bit_mask)) { 1454 features &= ~bit_mask; 1455 } 1456 bit++; 1457 } 1458 return features; 1459 } 1460 1461 void vhost_ack_features(struct vhost_dev *hdev, const int *feature_bits, 1462 uint64_t features) 1463 { 1464 const int *bit = feature_bits; 1465 while (*bit != VHOST_INVALID_FEATURE_BIT) { 1466 uint64_t bit_mask = (1ULL << *bit); 1467 if (features & bit_mask) { 1468 hdev->acked_features |= bit_mask; 1469 } 1470 bit++; 1471 } 1472 } 1473 1474 int vhost_dev_get_config(struct vhost_dev *hdev, uint8_t *config, 1475 uint32_t config_len) 1476 { 1477 assert(hdev->vhost_ops); 1478 1479 if (hdev->vhost_ops->vhost_get_config) { 1480 return hdev->vhost_ops->vhost_get_config(hdev, config, config_len); 1481 } 1482 1483 return -1; 1484 } 1485 1486 int vhost_dev_set_config(struct vhost_dev *hdev, const uint8_t *data, 1487 uint32_t offset, uint32_t size, uint32_t flags) 1488 { 1489 assert(hdev->vhost_ops); 1490 1491 if (hdev->vhost_ops->vhost_set_config) { 1492 return hdev->vhost_ops->vhost_set_config(hdev, data, offset, 1493 size, flags); 1494 } 1495 1496 return -1; 1497 } 1498 1499 void vhost_dev_set_config_notifier(struct vhost_dev *hdev, 1500 const VhostDevConfigOps *ops) 1501 { 1502 hdev->config_ops = ops; 1503 } 1504 1505 void vhost_dev_free_inflight(struct vhost_inflight *inflight) 1506 { 1507 if (inflight->addr) { 1508 qemu_memfd_free(inflight->addr, inflight->size, inflight->fd); 1509 inflight->addr = NULL; 1510 inflight->fd = -1; 1511 } 1512 } 1513 1514 static int vhost_dev_resize_inflight(struct vhost_inflight *inflight, 1515 uint64_t new_size) 1516 { 1517 Error *err = NULL; 1518 int fd = -1; 1519 void *addr = qemu_memfd_alloc("vhost-inflight", new_size, 1520 F_SEAL_GROW | F_SEAL_SHRINK | F_SEAL_SEAL, 1521 &fd, &err); 1522 1523 if (err) { 1524 error_report_err(err); 1525 return -1; 1526 } 1527 1528 vhost_dev_free_inflight(inflight); 1529 inflight->offset = 0; 1530 inflight->addr = addr; 1531 inflight->fd = fd; 1532 inflight->size = new_size; 1533 1534 return 0; 1535 } 1536 1537 void vhost_dev_save_inflight(struct vhost_inflight *inflight, QEMUFile *f) 1538 { 1539 if (inflight->addr) { 1540 qemu_put_be64(f, inflight->size); 1541 qemu_put_be16(f, inflight->queue_size); 1542 qemu_put_buffer(f, inflight->addr, inflight->size); 1543 } else { 1544 qemu_put_be64(f, 0); 1545 } 1546 } 1547 1548 int vhost_dev_load_inflight(struct vhost_inflight *inflight, QEMUFile *f) 1549 { 1550 uint64_t size; 1551 1552 size = qemu_get_be64(f); 1553 if (!size) { 1554 return 0; 1555 } 1556 1557 if (inflight->size != size) { 1558 if (vhost_dev_resize_inflight(inflight, size)) { 1559 return -1; 1560 } 1561 } 1562 inflight->queue_size = qemu_get_be16(f); 1563 1564 qemu_get_buffer(f, inflight->addr, size); 1565 1566 return 0; 1567 } 1568 1569 int vhost_dev_set_inflight(struct vhost_dev *dev, 1570 struct vhost_inflight *inflight) 1571 { 1572 int r; 1573 1574 if (dev->vhost_ops->vhost_set_inflight_fd && inflight->addr) { 1575 r = dev->vhost_ops->vhost_set_inflight_fd(dev, inflight); 1576 if (r) { 1577 VHOST_OPS_DEBUG("vhost_set_inflight_fd failed"); 1578 return -errno; 1579 } 1580 } 1581 1582 return 0; 1583 } 1584 1585 int vhost_dev_get_inflight(struct vhost_dev *dev, uint16_t queue_size, 1586 struct vhost_inflight *inflight) 1587 { 1588 int r; 1589 1590 if (dev->vhost_ops->vhost_get_inflight_fd) { 1591 r = dev->vhost_ops->vhost_get_inflight_fd(dev, queue_size, inflight); 1592 if (r) { 1593 VHOST_OPS_DEBUG("vhost_get_inflight_fd failed"); 1594 return -errno; 1595 } 1596 } 1597 1598 return 0; 1599 } 1600 1601 /* Host notifiers must be enabled at this point. */ 1602 int vhost_dev_start(struct vhost_dev *hdev, VirtIODevice *vdev) 1603 { 1604 int i, r; 1605 1606 /* should only be called after backend is connected */ 1607 assert(hdev->vhost_ops); 1608 1609 hdev->started = true; 1610 hdev->vdev = vdev; 1611 1612 r = vhost_dev_set_features(hdev, hdev->log_enabled); 1613 if (r < 0) { 1614 goto fail_features; 1615 } 1616 1617 if (vhost_dev_has_iommu(hdev)) { 1618 memory_listener_register(&hdev->iommu_listener, vdev->dma_as); 1619 } 1620 1621 r = hdev->vhost_ops->vhost_set_mem_table(hdev, hdev->mem); 1622 if (r < 0) { 1623 VHOST_OPS_DEBUG("vhost_set_mem_table failed"); 1624 r = -errno; 1625 goto fail_mem; 1626 } 1627 for (i = 0; i < hdev->nvqs; ++i) { 1628 r = vhost_virtqueue_start(hdev, 1629 vdev, 1630 hdev->vqs + i, 1631 hdev->vq_index + i); 1632 if (r < 0) { 1633 goto fail_vq; 1634 } 1635 } 1636 1637 if (hdev->log_enabled) { 1638 uint64_t log_base; 1639 1640 hdev->log_size = vhost_get_log_size(hdev); 1641 hdev->log = vhost_log_get(hdev->log_size, 1642 vhost_dev_log_is_shared(hdev)); 1643 log_base = (uintptr_t)hdev->log->log; 1644 r = hdev->vhost_ops->vhost_set_log_base(hdev, 1645 hdev->log_size ? log_base : 0, 1646 hdev->log); 1647 if (r < 0) { 1648 VHOST_OPS_DEBUG("vhost_set_log_base failed"); 1649 r = -errno; 1650 goto fail_log; 1651 } 1652 } 1653 1654 if (vhost_dev_has_iommu(hdev)) { 1655 hdev->vhost_ops->vhost_set_iotlb_callback(hdev, true); 1656 1657 /* Update used ring information for IOTLB to work correctly, 1658 * vhost-kernel code requires for this.*/ 1659 for (i = 0; i < hdev->nvqs; ++i) { 1660 struct vhost_virtqueue *vq = hdev->vqs + i; 1661 vhost_device_iotlb_miss(hdev, vq->used_phys, true); 1662 } 1663 } 1664 return 0; 1665 fail_log: 1666 vhost_log_put(hdev, false); 1667 fail_vq: 1668 while (--i >= 0) { 1669 vhost_virtqueue_stop(hdev, 1670 vdev, 1671 hdev->vqs + i, 1672 hdev->vq_index + i); 1673 } 1674 1675 fail_mem: 1676 fail_features: 1677 1678 hdev->started = false; 1679 return r; 1680 } 1681 1682 /* Host notifiers must be enabled at this point. */ 1683 void vhost_dev_stop(struct vhost_dev *hdev, VirtIODevice *vdev) 1684 { 1685 int i; 1686 1687 /* should only be called after backend is connected */ 1688 assert(hdev->vhost_ops); 1689 1690 for (i = 0; i < hdev->nvqs; ++i) { 1691 vhost_virtqueue_stop(hdev, 1692 vdev, 1693 hdev->vqs + i, 1694 hdev->vq_index + i); 1695 } 1696 1697 if (vhost_dev_has_iommu(hdev)) { 1698 hdev->vhost_ops->vhost_set_iotlb_callback(hdev, false); 1699 memory_listener_unregister(&hdev->iommu_listener); 1700 } 1701 vhost_log_put(hdev, true); 1702 hdev->started = false; 1703 hdev->vdev = NULL; 1704 } 1705 1706 int vhost_net_set_backend(struct vhost_dev *hdev, 1707 struct vhost_vring_file *file) 1708 { 1709 if (hdev->vhost_ops->vhost_net_set_backend) { 1710 return hdev->vhost_ops->vhost_net_set_backend(hdev, file); 1711 } 1712 1713 return -1; 1714 } 1715