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, int 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 size_t mrs_page = qemu_ram_pagesize(mrs_rb); 551 552 trace_vhost_region_add_section(section->mr->name, mrs_gpa, mrs_size, 553 mrs_host); 554 555 /* Round the section to it's page size */ 556 /* First align the start down to a page boundary */ 557 uint64_t alignage = mrs_host & (mrs_page - 1); 558 if (alignage) { 559 mrs_host -= alignage; 560 mrs_size += alignage; 561 mrs_gpa -= alignage; 562 } 563 /* Now align the size up to a page boundary */ 564 alignage = mrs_size & (mrs_page - 1); 565 if (alignage) { 566 mrs_size += mrs_page - alignage; 567 } 568 trace_vhost_region_add_section_aligned(section->mr->name, mrs_gpa, mrs_size, 569 mrs_host); 570 571 if (dev->n_tmp_sections) { 572 /* Since we already have at least one section, lets see if 573 * this extends it; since we're scanning in order, we only 574 * have to look at the last one, and the FlatView that calls 575 * us shouldn't have overlaps. 576 */ 577 MemoryRegionSection *prev_sec = dev->tmp_sections + 578 (dev->n_tmp_sections - 1); 579 uint64_t prev_gpa_start = prev_sec->offset_within_address_space; 580 uint64_t prev_size = int128_get64(prev_sec->size); 581 uint64_t prev_gpa_end = range_get_last(prev_gpa_start, prev_size); 582 uint64_t prev_host_start = 583 (uintptr_t)memory_region_get_ram_ptr(prev_sec->mr) + 584 prev_sec->offset_within_region; 585 uint64_t prev_host_end = range_get_last(prev_host_start, prev_size); 586 587 if (mrs_gpa <= (prev_gpa_end + 1)) { 588 /* OK, looks like overlapping/intersecting - it's possible that 589 * the rounding to page sizes has made them overlap, but they should 590 * match up in the same RAMBlock if they do. 591 */ 592 if (mrs_gpa < prev_gpa_start) { 593 error_report("%s:Section rounded to %"PRIx64 594 " prior to previous %"PRIx64, 595 __func__, mrs_gpa, prev_gpa_start); 596 /* A way to cleanly fail here would be better */ 597 return; 598 } 599 /* Offset from the start of the previous GPA to this GPA */ 600 size_t offset = mrs_gpa - prev_gpa_start; 601 602 if (prev_host_start + offset == mrs_host && 603 section->mr == prev_sec->mr && 604 (!dev->vhost_ops->vhost_backend_can_merge || 605 dev->vhost_ops->vhost_backend_can_merge(dev, 606 mrs_host, mrs_size, 607 prev_host_start, prev_size))) { 608 uint64_t max_end = MAX(prev_host_end, mrs_host + mrs_size); 609 need_add = false; 610 prev_sec->offset_within_address_space = 611 MIN(prev_gpa_start, mrs_gpa); 612 prev_sec->offset_within_region = 613 MIN(prev_host_start, mrs_host) - 614 (uintptr_t)memory_region_get_ram_ptr(prev_sec->mr); 615 prev_sec->size = int128_make64(max_end - MIN(prev_host_start, 616 mrs_host)); 617 trace_vhost_region_add_section_merge(section->mr->name, 618 int128_get64(prev_sec->size), 619 prev_sec->offset_within_address_space, 620 prev_sec->offset_within_region); 621 } else { 622 /* adjoining regions are fine, but overlapping ones with 623 * different blocks/offsets shouldn't happen 624 */ 625 if (mrs_gpa != prev_gpa_end + 1) { 626 error_report("%s: Overlapping but not coherent sections " 627 "at %"PRIx64, 628 __func__, mrs_gpa); 629 return; 630 } 631 } 632 } 633 } 634 635 if (need_add) { 636 ++dev->n_tmp_sections; 637 dev->tmp_sections = g_renew(MemoryRegionSection, dev->tmp_sections, 638 dev->n_tmp_sections); 639 dev->tmp_sections[dev->n_tmp_sections - 1] = *section; 640 /* The flatview isn't stable and we don't use it, making it NULL 641 * means we can memcmp the list. 642 */ 643 dev->tmp_sections[dev->n_tmp_sections - 1].fv = NULL; 644 memory_region_ref(section->mr); 645 } 646 } 647 648 /* Used for both add and nop callbacks */ 649 static void vhost_region_addnop(MemoryListener *listener, 650 MemoryRegionSection *section) 651 { 652 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 653 memory_listener); 654 655 if (!vhost_section(dev, section)) { 656 return; 657 } 658 vhost_region_add_section(dev, section); 659 } 660 661 static void vhost_iommu_unmap_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb) 662 { 663 struct vhost_iommu *iommu = container_of(n, struct vhost_iommu, n); 664 struct vhost_dev *hdev = iommu->hdev; 665 hwaddr iova = iotlb->iova + iommu->iommu_offset; 666 667 if (vhost_backend_invalidate_device_iotlb(hdev, iova, 668 iotlb->addr_mask + 1)) { 669 error_report("Fail to invalidate device iotlb"); 670 } 671 } 672 673 static void vhost_iommu_region_add(MemoryListener *listener, 674 MemoryRegionSection *section) 675 { 676 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 677 iommu_listener); 678 struct vhost_iommu *iommu; 679 Int128 end; 680 int iommu_idx, ret; 681 IOMMUMemoryRegion *iommu_mr; 682 Error *err = NULL; 683 684 if (!memory_region_is_iommu(section->mr)) { 685 return; 686 } 687 688 iommu_mr = IOMMU_MEMORY_REGION(section->mr); 689 690 iommu = g_malloc0(sizeof(*iommu)); 691 end = int128_add(int128_make64(section->offset_within_region), 692 section->size); 693 end = int128_sub(end, int128_one()); 694 iommu_idx = memory_region_iommu_attrs_to_index(iommu_mr, 695 MEMTXATTRS_UNSPECIFIED); 696 iommu_notifier_init(&iommu->n, vhost_iommu_unmap_notify, 697 IOMMU_NOTIFIER_UNMAP, 698 section->offset_within_region, 699 int128_get64(end), 700 iommu_idx); 701 iommu->mr = section->mr; 702 iommu->iommu_offset = section->offset_within_address_space - 703 section->offset_within_region; 704 iommu->hdev = dev; 705 ret = memory_region_register_iommu_notifier(section->mr, &iommu->n, &err); 706 if (ret) { 707 error_report_err(err); 708 exit(1); 709 } 710 QLIST_INSERT_HEAD(&dev->iommu_list, iommu, iommu_next); 711 /* TODO: can replay help performance here? */ 712 } 713 714 static void vhost_iommu_region_del(MemoryListener *listener, 715 MemoryRegionSection *section) 716 { 717 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 718 iommu_listener); 719 struct vhost_iommu *iommu; 720 721 if (!memory_region_is_iommu(section->mr)) { 722 return; 723 } 724 725 QLIST_FOREACH(iommu, &dev->iommu_list, iommu_next) { 726 if (iommu->mr == section->mr && 727 iommu->n.start == section->offset_within_region) { 728 memory_region_unregister_iommu_notifier(iommu->mr, 729 &iommu->n); 730 QLIST_REMOVE(iommu, iommu_next); 731 g_free(iommu); 732 break; 733 } 734 } 735 } 736 737 static int vhost_virtqueue_set_addr(struct vhost_dev *dev, 738 struct vhost_virtqueue *vq, 739 unsigned idx, bool enable_log) 740 { 741 struct vhost_vring_addr addr = { 742 .index = idx, 743 .desc_user_addr = (uint64_t)(unsigned long)vq->desc, 744 .avail_user_addr = (uint64_t)(unsigned long)vq->avail, 745 .used_user_addr = (uint64_t)(unsigned long)vq->used, 746 .log_guest_addr = vq->used_phys, 747 .flags = enable_log ? (1 << VHOST_VRING_F_LOG) : 0, 748 }; 749 int r = dev->vhost_ops->vhost_set_vring_addr(dev, &addr); 750 if (r < 0) { 751 VHOST_OPS_DEBUG("vhost_set_vring_addr failed"); 752 return -errno; 753 } 754 return 0; 755 } 756 757 static int vhost_dev_set_features(struct vhost_dev *dev, 758 bool enable_log) 759 { 760 uint64_t features = dev->acked_features; 761 int r; 762 if (enable_log) { 763 features |= 0x1ULL << VHOST_F_LOG_ALL; 764 } 765 r = dev->vhost_ops->vhost_set_features(dev, features); 766 if (r < 0) { 767 VHOST_OPS_DEBUG("vhost_set_features failed"); 768 } 769 return r < 0 ? -errno : 0; 770 } 771 772 static int vhost_dev_set_log(struct vhost_dev *dev, bool enable_log) 773 { 774 int r, i, idx; 775 r = vhost_dev_set_features(dev, enable_log); 776 if (r < 0) { 777 goto err_features; 778 } 779 for (i = 0; i < dev->nvqs; ++i) { 780 idx = dev->vhost_ops->vhost_get_vq_index(dev, dev->vq_index + i); 781 r = vhost_virtqueue_set_addr(dev, dev->vqs + i, idx, 782 enable_log); 783 if (r < 0) { 784 goto err_vq; 785 } 786 } 787 return 0; 788 err_vq: 789 for (; i >= 0; --i) { 790 idx = dev->vhost_ops->vhost_get_vq_index(dev, dev->vq_index + i); 791 vhost_virtqueue_set_addr(dev, dev->vqs + i, idx, 792 dev->log_enabled); 793 } 794 vhost_dev_set_features(dev, dev->log_enabled); 795 err_features: 796 return r; 797 } 798 799 static int vhost_migration_log(MemoryListener *listener, int enable) 800 { 801 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 802 memory_listener); 803 int r; 804 if (!!enable == dev->log_enabled) { 805 return 0; 806 } 807 if (!dev->started) { 808 dev->log_enabled = enable; 809 return 0; 810 } 811 if (!enable) { 812 r = vhost_dev_set_log(dev, false); 813 if (r < 0) { 814 return r; 815 } 816 vhost_log_put(dev, false); 817 } else { 818 vhost_dev_log_resize(dev, vhost_get_log_size(dev)); 819 r = vhost_dev_set_log(dev, true); 820 if (r < 0) { 821 return r; 822 } 823 } 824 dev->log_enabled = enable; 825 return 0; 826 } 827 828 static void vhost_log_global_start(MemoryListener *listener) 829 { 830 int r; 831 832 r = vhost_migration_log(listener, true); 833 if (r < 0) { 834 abort(); 835 } 836 } 837 838 static void vhost_log_global_stop(MemoryListener *listener) 839 { 840 int r; 841 842 r = vhost_migration_log(listener, false); 843 if (r < 0) { 844 abort(); 845 } 846 } 847 848 static void vhost_log_start(MemoryListener *listener, 849 MemoryRegionSection *section, 850 int old, int new) 851 { 852 /* FIXME: implement */ 853 } 854 855 static void vhost_log_stop(MemoryListener *listener, 856 MemoryRegionSection *section, 857 int old, int new) 858 { 859 /* FIXME: implement */ 860 } 861 862 /* The vhost driver natively knows how to handle the vrings of non 863 * cross-endian legacy devices and modern devices. Only legacy devices 864 * exposed to a bi-endian guest may require the vhost driver to use a 865 * specific endianness. 866 */ 867 static inline bool vhost_needs_vring_endian(VirtIODevice *vdev) 868 { 869 if (virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) { 870 return false; 871 } 872 #ifdef HOST_WORDS_BIGENDIAN 873 return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_LITTLE; 874 #else 875 return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG; 876 #endif 877 } 878 879 static int vhost_virtqueue_set_vring_endian_legacy(struct vhost_dev *dev, 880 bool is_big_endian, 881 int vhost_vq_index) 882 { 883 struct vhost_vring_state s = { 884 .index = vhost_vq_index, 885 .num = is_big_endian 886 }; 887 888 if (!dev->vhost_ops->vhost_set_vring_endian(dev, &s)) { 889 return 0; 890 } 891 892 VHOST_OPS_DEBUG("vhost_set_vring_endian failed"); 893 if (errno == ENOTTY) { 894 error_report("vhost does not support cross-endian"); 895 return -ENOSYS; 896 } 897 898 return -errno; 899 } 900 901 static int vhost_memory_region_lookup(struct vhost_dev *hdev, 902 uint64_t gpa, uint64_t *uaddr, 903 uint64_t *len) 904 { 905 int i; 906 907 for (i = 0; i < hdev->mem->nregions; i++) { 908 struct vhost_memory_region *reg = hdev->mem->regions + i; 909 910 if (gpa >= reg->guest_phys_addr && 911 reg->guest_phys_addr + reg->memory_size > gpa) { 912 *uaddr = reg->userspace_addr + gpa - reg->guest_phys_addr; 913 *len = reg->guest_phys_addr + reg->memory_size - gpa; 914 return 0; 915 } 916 } 917 918 return -EFAULT; 919 } 920 921 int vhost_device_iotlb_miss(struct vhost_dev *dev, uint64_t iova, int write) 922 { 923 IOMMUTLBEntry iotlb; 924 uint64_t uaddr, len; 925 int ret = -EFAULT; 926 927 rcu_read_lock(); 928 929 trace_vhost_iotlb_miss(dev, 1); 930 931 iotlb = address_space_get_iotlb_entry(dev->vdev->dma_as, 932 iova, write, 933 MEMTXATTRS_UNSPECIFIED); 934 if (iotlb.target_as != NULL) { 935 ret = vhost_memory_region_lookup(dev, iotlb.translated_addr, 936 &uaddr, &len); 937 if (ret) { 938 trace_vhost_iotlb_miss(dev, 3); 939 error_report("Fail to lookup the translated address " 940 "%"PRIx64, iotlb.translated_addr); 941 goto out; 942 } 943 944 len = MIN(iotlb.addr_mask + 1, len); 945 iova = iova & ~iotlb.addr_mask; 946 947 ret = vhost_backend_update_device_iotlb(dev, iova, uaddr, 948 len, iotlb.perm); 949 if (ret) { 950 trace_vhost_iotlb_miss(dev, 4); 951 error_report("Fail to update device iotlb"); 952 goto out; 953 } 954 } 955 956 trace_vhost_iotlb_miss(dev, 2); 957 958 out: 959 rcu_read_unlock(); 960 961 return ret; 962 } 963 964 static int vhost_virtqueue_start(struct vhost_dev *dev, 965 struct VirtIODevice *vdev, 966 struct vhost_virtqueue *vq, 967 unsigned idx) 968 { 969 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); 970 VirtioBusState *vbus = VIRTIO_BUS(qbus); 971 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(vbus); 972 hwaddr s, l, a; 973 int r; 974 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, idx); 975 struct vhost_vring_file file = { 976 .index = vhost_vq_index 977 }; 978 struct vhost_vring_state state = { 979 .index = vhost_vq_index 980 }; 981 struct VirtQueue *vvq = virtio_get_queue(vdev, idx); 982 983 a = virtio_queue_get_desc_addr(vdev, idx); 984 if (a == 0) { 985 /* Queue might not be ready for start */ 986 return 0; 987 } 988 989 vq->num = state.num = virtio_queue_get_num(vdev, idx); 990 r = dev->vhost_ops->vhost_set_vring_num(dev, &state); 991 if (r) { 992 VHOST_OPS_DEBUG("vhost_set_vring_num failed"); 993 return -errno; 994 } 995 996 state.num = virtio_queue_get_last_avail_idx(vdev, idx); 997 r = dev->vhost_ops->vhost_set_vring_base(dev, &state); 998 if (r) { 999 VHOST_OPS_DEBUG("vhost_set_vring_base failed"); 1000 return -errno; 1001 } 1002 1003 if (vhost_needs_vring_endian(vdev)) { 1004 r = vhost_virtqueue_set_vring_endian_legacy(dev, 1005 virtio_is_big_endian(vdev), 1006 vhost_vq_index); 1007 if (r) { 1008 return -errno; 1009 } 1010 } 1011 1012 vq->desc_size = s = l = virtio_queue_get_desc_size(vdev, idx); 1013 vq->desc_phys = a; 1014 vq->desc = vhost_memory_map(dev, a, &l, 0); 1015 if (!vq->desc || l != s) { 1016 r = -ENOMEM; 1017 goto fail_alloc_desc; 1018 } 1019 vq->avail_size = s = l = virtio_queue_get_avail_size(vdev, idx); 1020 vq->avail_phys = a = virtio_queue_get_avail_addr(vdev, idx); 1021 vq->avail = vhost_memory_map(dev, a, &l, 0); 1022 if (!vq->avail || l != s) { 1023 r = -ENOMEM; 1024 goto fail_alloc_avail; 1025 } 1026 vq->used_size = s = l = virtio_queue_get_used_size(vdev, idx); 1027 vq->used_phys = a = virtio_queue_get_used_addr(vdev, idx); 1028 vq->used = vhost_memory_map(dev, a, &l, 1); 1029 if (!vq->used || l != s) { 1030 r = -ENOMEM; 1031 goto fail_alloc_used; 1032 } 1033 1034 r = vhost_virtqueue_set_addr(dev, vq, vhost_vq_index, dev->log_enabled); 1035 if (r < 0) { 1036 r = -errno; 1037 goto fail_alloc; 1038 } 1039 1040 file.fd = event_notifier_get_fd(virtio_queue_get_host_notifier(vvq)); 1041 r = dev->vhost_ops->vhost_set_vring_kick(dev, &file); 1042 if (r) { 1043 VHOST_OPS_DEBUG("vhost_set_vring_kick failed"); 1044 r = -errno; 1045 goto fail_kick; 1046 } 1047 1048 /* Clear and discard previous events if any. */ 1049 event_notifier_test_and_clear(&vq->masked_notifier); 1050 1051 /* Init vring in unmasked state, unless guest_notifier_mask 1052 * will do it later. 1053 */ 1054 if (!vdev->use_guest_notifier_mask) { 1055 /* TODO: check and handle errors. */ 1056 vhost_virtqueue_mask(dev, vdev, idx, false); 1057 } 1058 1059 if (k->query_guest_notifiers && 1060 k->query_guest_notifiers(qbus->parent) && 1061 virtio_queue_vector(vdev, idx) == VIRTIO_NO_VECTOR) { 1062 file.fd = -1; 1063 r = dev->vhost_ops->vhost_set_vring_call(dev, &file); 1064 if (r) { 1065 goto fail_vector; 1066 } 1067 } 1068 1069 return 0; 1070 1071 fail_vector: 1072 fail_kick: 1073 fail_alloc: 1074 vhost_memory_unmap(dev, vq->used, virtio_queue_get_used_size(vdev, idx), 1075 0, 0); 1076 fail_alloc_used: 1077 vhost_memory_unmap(dev, vq->avail, virtio_queue_get_avail_size(vdev, idx), 1078 0, 0); 1079 fail_alloc_avail: 1080 vhost_memory_unmap(dev, vq->desc, virtio_queue_get_desc_size(vdev, idx), 1081 0, 0); 1082 fail_alloc_desc: 1083 return r; 1084 } 1085 1086 static void vhost_virtqueue_stop(struct vhost_dev *dev, 1087 struct VirtIODevice *vdev, 1088 struct vhost_virtqueue *vq, 1089 unsigned idx) 1090 { 1091 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, idx); 1092 struct vhost_vring_state state = { 1093 .index = vhost_vq_index, 1094 }; 1095 int r; 1096 1097 if (virtio_queue_get_desc_addr(vdev, idx) == 0) { 1098 /* Don't stop the virtqueue which might have not been started */ 1099 return; 1100 } 1101 1102 r = dev->vhost_ops->vhost_get_vring_base(dev, &state); 1103 if (r < 0) { 1104 VHOST_OPS_DEBUG("vhost VQ %u ring restore failed: %d", idx, r); 1105 /* Connection to the backend is broken, so let's sync internal 1106 * last avail idx to the device used idx. 1107 */ 1108 virtio_queue_restore_last_avail_idx(vdev, idx); 1109 } else { 1110 virtio_queue_set_last_avail_idx(vdev, idx, state.num); 1111 } 1112 virtio_queue_invalidate_signalled_used(vdev, idx); 1113 virtio_queue_update_used_idx(vdev, idx); 1114 1115 /* In the cross-endian case, we need to reset the vring endianness to 1116 * native as legacy devices expect so by default. 1117 */ 1118 if (vhost_needs_vring_endian(vdev)) { 1119 vhost_virtqueue_set_vring_endian_legacy(dev, 1120 !virtio_is_big_endian(vdev), 1121 vhost_vq_index); 1122 } 1123 1124 vhost_memory_unmap(dev, vq->used, virtio_queue_get_used_size(vdev, idx), 1125 1, virtio_queue_get_used_size(vdev, idx)); 1126 vhost_memory_unmap(dev, vq->avail, virtio_queue_get_avail_size(vdev, idx), 1127 0, virtio_queue_get_avail_size(vdev, idx)); 1128 vhost_memory_unmap(dev, vq->desc, virtio_queue_get_desc_size(vdev, idx), 1129 0, virtio_queue_get_desc_size(vdev, idx)); 1130 } 1131 1132 static void vhost_eventfd_add(MemoryListener *listener, 1133 MemoryRegionSection *section, 1134 bool match_data, uint64_t data, EventNotifier *e) 1135 { 1136 } 1137 1138 static void vhost_eventfd_del(MemoryListener *listener, 1139 MemoryRegionSection *section, 1140 bool match_data, uint64_t data, EventNotifier *e) 1141 { 1142 } 1143 1144 static int vhost_virtqueue_set_busyloop_timeout(struct vhost_dev *dev, 1145 int n, uint32_t timeout) 1146 { 1147 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, n); 1148 struct vhost_vring_state state = { 1149 .index = vhost_vq_index, 1150 .num = timeout, 1151 }; 1152 int r; 1153 1154 if (!dev->vhost_ops->vhost_set_vring_busyloop_timeout) { 1155 return -EINVAL; 1156 } 1157 1158 r = dev->vhost_ops->vhost_set_vring_busyloop_timeout(dev, &state); 1159 if (r) { 1160 VHOST_OPS_DEBUG("vhost_set_vring_busyloop_timeout failed"); 1161 return r; 1162 } 1163 1164 return 0; 1165 } 1166 1167 static int vhost_virtqueue_init(struct vhost_dev *dev, 1168 struct vhost_virtqueue *vq, int n) 1169 { 1170 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, n); 1171 struct vhost_vring_file file = { 1172 .index = vhost_vq_index, 1173 }; 1174 int r = event_notifier_init(&vq->masked_notifier, 0); 1175 if (r < 0) { 1176 return r; 1177 } 1178 1179 file.fd = event_notifier_get_fd(&vq->masked_notifier); 1180 r = dev->vhost_ops->vhost_set_vring_call(dev, &file); 1181 if (r) { 1182 VHOST_OPS_DEBUG("vhost_set_vring_call failed"); 1183 r = -errno; 1184 goto fail_call; 1185 } 1186 1187 vq->dev = dev; 1188 1189 return 0; 1190 fail_call: 1191 event_notifier_cleanup(&vq->masked_notifier); 1192 return r; 1193 } 1194 1195 static void vhost_virtqueue_cleanup(struct vhost_virtqueue *vq) 1196 { 1197 event_notifier_cleanup(&vq->masked_notifier); 1198 } 1199 1200 int vhost_dev_init(struct vhost_dev *hdev, void *opaque, 1201 VhostBackendType backend_type, uint32_t busyloop_timeout) 1202 { 1203 uint64_t features; 1204 int i, r, n_initialized_vqs = 0; 1205 Error *local_err = NULL; 1206 1207 hdev->vdev = NULL; 1208 hdev->migration_blocker = NULL; 1209 1210 r = vhost_set_backend_type(hdev, backend_type); 1211 assert(r >= 0); 1212 1213 r = hdev->vhost_ops->vhost_backend_init(hdev, opaque); 1214 if (r < 0) { 1215 goto fail; 1216 } 1217 1218 r = hdev->vhost_ops->vhost_set_owner(hdev); 1219 if (r < 0) { 1220 VHOST_OPS_DEBUG("vhost_set_owner failed"); 1221 goto fail; 1222 } 1223 1224 r = hdev->vhost_ops->vhost_get_features(hdev, &features); 1225 if (r < 0) { 1226 VHOST_OPS_DEBUG("vhost_get_features failed"); 1227 goto fail; 1228 } 1229 1230 for (i = 0; i < hdev->nvqs; ++i, ++n_initialized_vqs) { 1231 r = vhost_virtqueue_init(hdev, hdev->vqs + i, hdev->vq_index + i); 1232 if (r < 0) { 1233 goto fail; 1234 } 1235 } 1236 1237 if (busyloop_timeout) { 1238 for (i = 0; i < hdev->nvqs; ++i) { 1239 r = vhost_virtqueue_set_busyloop_timeout(hdev, hdev->vq_index + i, 1240 busyloop_timeout); 1241 if (r < 0) { 1242 goto fail_busyloop; 1243 } 1244 } 1245 } 1246 1247 hdev->features = features; 1248 1249 hdev->memory_listener = (MemoryListener) { 1250 .begin = vhost_begin, 1251 .commit = vhost_commit, 1252 .region_add = vhost_region_addnop, 1253 .region_nop = vhost_region_addnop, 1254 .log_start = vhost_log_start, 1255 .log_stop = vhost_log_stop, 1256 .log_sync = vhost_log_sync, 1257 .log_global_start = vhost_log_global_start, 1258 .log_global_stop = vhost_log_global_stop, 1259 .eventfd_add = vhost_eventfd_add, 1260 .eventfd_del = vhost_eventfd_del, 1261 .priority = 10 1262 }; 1263 1264 hdev->iommu_listener = (MemoryListener) { 1265 .region_add = vhost_iommu_region_add, 1266 .region_del = vhost_iommu_region_del, 1267 }; 1268 1269 if (hdev->migration_blocker == NULL) { 1270 if (!(hdev->features & (0x1ULL << VHOST_F_LOG_ALL))) { 1271 error_setg(&hdev->migration_blocker, 1272 "Migration disabled: vhost lacks VHOST_F_LOG_ALL feature."); 1273 } else if (vhost_dev_log_is_shared(hdev) && !qemu_memfd_alloc_check()) { 1274 error_setg(&hdev->migration_blocker, 1275 "Migration disabled: failed to allocate shared memory"); 1276 } 1277 } 1278 1279 if (hdev->migration_blocker != NULL) { 1280 r = migrate_add_blocker(hdev->migration_blocker, &local_err); 1281 if (local_err) { 1282 error_report_err(local_err); 1283 error_free(hdev->migration_blocker); 1284 goto fail_busyloop; 1285 } 1286 } 1287 1288 hdev->mem = g_malloc0(offsetof(struct vhost_memory, regions)); 1289 hdev->n_mem_sections = 0; 1290 hdev->mem_sections = NULL; 1291 hdev->log = NULL; 1292 hdev->log_size = 0; 1293 hdev->log_enabled = false; 1294 hdev->started = false; 1295 memory_listener_register(&hdev->memory_listener, &address_space_memory); 1296 QLIST_INSERT_HEAD(&vhost_devices, hdev, entry); 1297 1298 if (used_memslots > hdev->vhost_ops->vhost_backend_memslots_limit(hdev)) { 1299 error_report("vhost backend memory slots limit is less" 1300 " than current number of present memory slots"); 1301 r = -1; 1302 if (busyloop_timeout) { 1303 goto fail_busyloop; 1304 } else { 1305 goto fail; 1306 } 1307 } 1308 1309 return 0; 1310 1311 fail_busyloop: 1312 while (--i >= 0) { 1313 vhost_virtqueue_set_busyloop_timeout(hdev, hdev->vq_index + i, 0); 1314 } 1315 fail: 1316 hdev->nvqs = n_initialized_vqs; 1317 vhost_dev_cleanup(hdev); 1318 return r; 1319 } 1320 1321 void vhost_dev_cleanup(struct vhost_dev *hdev) 1322 { 1323 int i; 1324 1325 for (i = 0; i < hdev->nvqs; ++i) { 1326 vhost_virtqueue_cleanup(hdev->vqs + i); 1327 } 1328 if (hdev->mem) { 1329 /* those are only safe after successful init */ 1330 memory_listener_unregister(&hdev->memory_listener); 1331 QLIST_REMOVE(hdev, entry); 1332 } 1333 if (hdev->migration_blocker) { 1334 migrate_del_blocker(hdev->migration_blocker); 1335 error_free(hdev->migration_blocker); 1336 } 1337 g_free(hdev->mem); 1338 g_free(hdev->mem_sections); 1339 if (hdev->vhost_ops) { 1340 hdev->vhost_ops->vhost_backend_cleanup(hdev); 1341 } 1342 assert(!hdev->log); 1343 1344 memset(hdev, 0, sizeof(struct vhost_dev)); 1345 } 1346 1347 /* Stop processing guest IO notifications in qemu. 1348 * Start processing them in vhost in kernel. 1349 */ 1350 int vhost_dev_enable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev) 1351 { 1352 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); 1353 int i, r, e; 1354 1355 /* We will pass the notifiers to the kernel, make sure that QEMU 1356 * doesn't interfere. 1357 */ 1358 r = virtio_device_grab_ioeventfd(vdev); 1359 if (r < 0) { 1360 error_report("binding does not support host notifiers"); 1361 goto fail; 1362 } 1363 1364 for (i = 0; i < hdev->nvqs; ++i) { 1365 r = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i, 1366 true); 1367 if (r < 0) { 1368 error_report("vhost VQ %d notifier binding failed: %d", i, -r); 1369 goto fail_vq; 1370 } 1371 } 1372 1373 return 0; 1374 fail_vq: 1375 while (--i >= 0) { 1376 e = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i, 1377 false); 1378 if (e < 0) { 1379 error_report("vhost VQ %d notifier cleanup error: %d", i, -r); 1380 } 1381 assert (e >= 0); 1382 virtio_bus_cleanup_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i); 1383 } 1384 virtio_device_release_ioeventfd(vdev); 1385 fail: 1386 return r; 1387 } 1388 1389 /* Stop processing guest IO notifications in vhost. 1390 * Start processing them in qemu. 1391 * This might actually run the qemu handlers right away, 1392 * so virtio in qemu must be completely setup when this is called. 1393 */ 1394 void vhost_dev_disable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev) 1395 { 1396 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); 1397 int i, r; 1398 1399 for (i = 0; i < hdev->nvqs; ++i) { 1400 r = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i, 1401 false); 1402 if (r < 0) { 1403 error_report("vhost VQ %d notifier cleanup failed: %d", i, -r); 1404 } 1405 assert (r >= 0); 1406 virtio_bus_cleanup_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i); 1407 } 1408 virtio_device_release_ioeventfd(vdev); 1409 } 1410 1411 /* Test and clear event pending status. 1412 * Should be called after unmask to avoid losing events. 1413 */ 1414 bool vhost_virtqueue_pending(struct vhost_dev *hdev, int n) 1415 { 1416 struct vhost_virtqueue *vq = hdev->vqs + n - hdev->vq_index; 1417 assert(n >= hdev->vq_index && n < hdev->vq_index + hdev->nvqs); 1418 return event_notifier_test_and_clear(&vq->masked_notifier); 1419 } 1420 1421 /* Mask/unmask events from this vq. */ 1422 void vhost_virtqueue_mask(struct vhost_dev *hdev, VirtIODevice *vdev, int n, 1423 bool mask) 1424 { 1425 struct VirtQueue *vvq = virtio_get_queue(vdev, n); 1426 int r, index = n - hdev->vq_index; 1427 struct vhost_vring_file file; 1428 1429 /* should only be called after backend is connected */ 1430 assert(hdev->vhost_ops); 1431 1432 if (mask) { 1433 assert(vdev->use_guest_notifier_mask); 1434 file.fd = event_notifier_get_fd(&hdev->vqs[index].masked_notifier); 1435 } else { 1436 file.fd = event_notifier_get_fd(virtio_queue_get_guest_notifier(vvq)); 1437 } 1438 1439 file.index = hdev->vhost_ops->vhost_get_vq_index(hdev, n); 1440 r = hdev->vhost_ops->vhost_set_vring_call(hdev, &file); 1441 if (r < 0) { 1442 VHOST_OPS_DEBUG("vhost_set_vring_call failed"); 1443 } 1444 } 1445 1446 uint64_t vhost_get_features(struct vhost_dev *hdev, const int *feature_bits, 1447 uint64_t features) 1448 { 1449 const int *bit = feature_bits; 1450 while (*bit != VHOST_INVALID_FEATURE_BIT) { 1451 uint64_t bit_mask = (1ULL << *bit); 1452 if (!(hdev->features & bit_mask)) { 1453 features &= ~bit_mask; 1454 } 1455 bit++; 1456 } 1457 return features; 1458 } 1459 1460 void vhost_ack_features(struct vhost_dev *hdev, const int *feature_bits, 1461 uint64_t features) 1462 { 1463 const int *bit = feature_bits; 1464 while (*bit != VHOST_INVALID_FEATURE_BIT) { 1465 uint64_t bit_mask = (1ULL << *bit); 1466 if (features & bit_mask) { 1467 hdev->acked_features |= bit_mask; 1468 } 1469 bit++; 1470 } 1471 } 1472 1473 int vhost_dev_get_config(struct vhost_dev *hdev, uint8_t *config, 1474 uint32_t config_len) 1475 { 1476 assert(hdev->vhost_ops); 1477 1478 if (hdev->vhost_ops->vhost_get_config) { 1479 return hdev->vhost_ops->vhost_get_config(hdev, config, config_len); 1480 } 1481 1482 return -1; 1483 } 1484 1485 int vhost_dev_set_config(struct vhost_dev *hdev, const uint8_t *data, 1486 uint32_t offset, uint32_t size, uint32_t flags) 1487 { 1488 assert(hdev->vhost_ops); 1489 1490 if (hdev->vhost_ops->vhost_set_config) { 1491 return hdev->vhost_ops->vhost_set_config(hdev, data, offset, 1492 size, flags); 1493 } 1494 1495 return -1; 1496 } 1497 1498 void vhost_dev_set_config_notifier(struct vhost_dev *hdev, 1499 const VhostDevConfigOps *ops) 1500 { 1501 hdev->config_ops = ops; 1502 } 1503 1504 void vhost_dev_free_inflight(struct vhost_inflight *inflight) 1505 { 1506 if (inflight->addr) { 1507 qemu_memfd_free(inflight->addr, inflight->size, inflight->fd); 1508 inflight->addr = NULL; 1509 inflight->fd = -1; 1510 } 1511 } 1512 1513 static int vhost_dev_resize_inflight(struct vhost_inflight *inflight, 1514 uint64_t new_size) 1515 { 1516 Error *err = NULL; 1517 int fd = -1; 1518 void *addr = qemu_memfd_alloc("vhost-inflight", new_size, 1519 F_SEAL_GROW | F_SEAL_SHRINK | F_SEAL_SEAL, 1520 &fd, &err); 1521 1522 if (err) { 1523 error_report_err(err); 1524 return -1; 1525 } 1526 1527 vhost_dev_free_inflight(inflight); 1528 inflight->offset = 0; 1529 inflight->addr = addr; 1530 inflight->fd = fd; 1531 inflight->size = new_size; 1532 1533 return 0; 1534 } 1535 1536 void vhost_dev_save_inflight(struct vhost_inflight *inflight, QEMUFile *f) 1537 { 1538 if (inflight->addr) { 1539 qemu_put_be64(f, inflight->size); 1540 qemu_put_be16(f, inflight->queue_size); 1541 qemu_put_buffer(f, inflight->addr, inflight->size); 1542 } else { 1543 qemu_put_be64(f, 0); 1544 } 1545 } 1546 1547 int vhost_dev_load_inflight(struct vhost_inflight *inflight, QEMUFile *f) 1548 { 1549 uint64_t size; 1550 1551 size = qemu_get_be64(f); 1552 if (!size) { 1553 return 0; 1554 } 1555 1556 if (inflight->size != size) { 1557 if (vhost_dev_resize_inflight(inflight, size)) { 1558 return -1; 1559 } 1560 } 1561 inflight->queue_size = qemu_get_be16(f); 1562 1563 qemu_get_buffer(f, inflight->addr, size); 1564 1565 return 0; 1566 } 1567 1568 int vhost_dev_set_inflight(struct vhost_dev *dev, 1569 struct vhost_inflight *inflight) 1570 { 1571 int r; 1572 1573 if (dev->vhost_ops->vhost_set_inflight_fd && inflight->addr) { 1574 r = dev->vhost_ops->vhost_set_inflight_fd(dev, inflight); 1575 if (r) { 1576 VHOST_OPS_DEBUG("vhost_set_inflight_fd failed"); 1577 return -errno; 1578 } 1579 } 1580 1581 return 0; 1582 } 1583 1584 int vhost_dev_get_inflight(struct vhost_dev *dev, uint16_t queue_size, 1585 struct vhost_inflight *inflight) 1586 { 1587 int r; 1588 1589 if (dev->vhost_ops->vhost_get_inflight_fd) { 1590 r = dev->vhost_ops->vhost_get_inflight_fd(dev, queue_size, inflight); 1591 if (r) { 1592 VHOST_OPS_DEBUG("vhost_get_inflight_fd failed"); 1593 return -errno; 1594 } 1595 } 1596 1597 return 0; 1598 } 1599 1600 /* Host notifiers must be enabled at this point. */ 1601 int vhost_dev_start(struct vhost_dev *hdev, VirtIODevice *vdev) 1602 { 1603 int i, r; 1604 1605 /* should only be called after backend is connected */ 1606 assert(hdev->vhost_ops); 1607 1608 hdev->started = true; 1609 hdev->vdev = vdev; 1610 1611 r = vhost_dev_set_features(hdev, hdev->log_enabled); 1612 if (r < 0) { 1613 goto fail_features; 1614 } 1615 1616 if (vhost_dev_has_iommu(hdev)) { 1617 memory_listener_register(&hdev->iommu_listener, vdev->dma_as); 1618 } 1619 1620 r = hdev->vhost_ops->vhost_set_mem_table(hdev, hdev->mem); 1621 if (r < 0) { 1622 VHOST_OPS_DEBUG("vhost_set_mem_table failed"); 1623 r = -errno; 1624 goto fail_mem; 1625 } 1626 for (i = 0; i < hdev->nvqs; ++i) { 1627 r = vhost_virtqueue_start(hdev, 1628 vdev, 1629 hdev->vqs + i, 1630 hdev->vq_index + i); 1631 if (r < 0) { 1632 goto fail_vq; 1633 } 1634 } 1635 1636 if (hdev->log_enabled) { 1637 uint64_t log_base; 1638 1639 hdev->log_size = vhost_get_log_size(hdev); 1640 hdev->log = vhost_log_get(hdev->log_size, 1641 vhost_dev_log_is_shared(hdev)); 1642 log_base = (uintptr_t)hdev->log->log; 1643 r = hdev->vhost_ops->vhost_set_log_base(hdev, 1644 hdev->log_size ? log_base : 0, 1645 hdev->log); 1646 if (r < 0) { 1647 VHOST_OPS_DEBUG("vhost_set_log_base failed"); 1648 r = -errno; 1649 goto fail_log; 1650 } 1651 } 1652 1653 if (vhost_dev_has_iommu(hdev)) { 1654 hdev->vhost_ops->vhost_set_iotlb_callback(hdev, true); 1655 1656 /* Update used ring information for IOTLB to work correctly, 1657 * vhost-kernel code requires for this.*/ 1658 for (i = 0; i < hdev->nvqs; ++i) { 1659 struct vhost_virtqueue *vq = hdev->vqs + i; 1660 vhost_device_iotlb_miss(hdev, vq->used_phys, true); 1661 } 1662 } 1663 return 0; 1664 fail_log: 1665 vhost_log_put(hdev, false); 1666 fail_vq: 1667 while (--i >= 0) { 1668 vhost_virtqueue_stop(hdev, 1669 vdev, 1670 hdev->vqs + i, 1671 hdev->vq_index + i); 1672 } 1673 1674 fail_mem: 1675 fail_features: 1676 1677 hdev->started = false; 1678 return r; 1679 } 1680 1681 /* Host notifiers must be enabled at this point. */ 1682 void vhost_dev_stop(struct vhost_dev *hdev, VirtIODevice *vdev) 1683 { 1684 int i; 1685 1686 /* should only be called after backend is connected */ 1687 assert(hdev->vhost_ops); 1688 1689 for (i = 0; i < hdev->nvqs; ++i) { 1690 vhost_virtqueue_stop(hdev, 1691 vdev, 1692 hdev->vqs + i, 1693 hdev->vq_index + i); 1694 } 1695 1696 if (vhost_dev_has_iommu(hdev)) { 1697 hdev->vhost_ops->vhost_set_iotlb_callback(hdev, false); 1698 memory_listener_unregister(&hdev->iommu_listener); 1699 } 1700 vhost_log_put(hdev, true); 1701 hdev->started = false; 1702 hdev->vdev = NULL; 1703 } 1704 1705 int vhost_net_set_backend(struct vhost_dev *hdev, 1706 struct vhost_vring_file *file) 1707 { 1708 if (hdev->vhost_ops->vhost_net_set_backend) { 1709 return hdev->vhost_ops->vhost_net_set_backend(hdev, file); 1710 } 1711 1712 return -1; 1713 } 1714