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 "qemu/log.h" 24 #include "standard-headers/linux/vhost_types.h" 25 #include "hw/virtio/virtio-bus.h" 26 #include "migration/blocker.h" 27 #include "migration/qemu-file-types.h" 28 #include "sysemu/dma.h" 29 #include "trace.h" 30 31 /* enabled until disconnected backend stabilizes */ 32 #define _VHOST_DEBUG 1 33 34 #ifdef _VHOST_DEBUG 35 #define VHOST_OPS_DEBUG(retval, fmt, ...) \ 36 do { \ 37 error_report(fmt ": %s (%d)", ## __VA_ARGS__, \ 38 strerror(-retval), -retval); \ 39 } while (0) 40 #else 41 #define VHOST_OPS_DEBUG(retval, fmt, ...) \ 42 do { } while (0) 43 #endif 44 45 static struct vhost_log *vhost_log; 46 static struct vhost_log *vhost_log_shm; 47 48 static unsigned int used_memslots; 49 static QLIST_HEAD(, vhost_dev) vhost_devices = 50 QLIST_HEAD_INITIALIZER(vhost_devices); 51 52 bool vhost_has_free_slot(void) 53 { 54 unsigned int slots_limit = ~0U; 55 struct vhost_dev *hdev; 56 57 QLIST_FOREACH(hdev, &vhost_devices, entry) { 58 unsigned int r = hdev->vhost_ops->vhost_backend_memslots_limit(hdev); 59 slots_limit = MIN(slots_limit, r); 60 } 61 return slots_limit > used_memslots; 62 } 63 64 static void vhost_dev_sync_region(struct vhost_dev *dev, 65 MemoryRegionSection *section, 66 uint64_t mfirst, uint64_t mlast, 67 uint64_t rfirst, uint64_t rlast) 68 { 69 vhost_log_chunk_t *log = dev->log->log; 70 71 uint64_t start = MAX(mfirst, rfirst); 72 uint64_t end = MIN(mlast, rlast); 73 vhost_log_chunk_t *from = log + start / VHOST_LOG_CHUNK; 74 vhost_log_chunk_t *to = log + end / VHOST_LOG_CHUNK + 1; 75 uint64_t addr = QEMU_ALIGN_DOWN(start, VHOST_LOG_CHUNK); 76 77 if (end < start) { 78 return; 79 } 80 assert(end / VHOST_LOG_CHUNK < dev->log_size); 81 assert(start / VHOST_LOG_CHUNK < dev->log_size); 82 83 for (;from < to; ++from) { 84 vhost_log_chunk_t log; 85 /* We first check with non-atomic: much cheaper, 86 * and we expect non-dirty to be the common case. */ 87 if (!*from) { 88 addr += VHOST_LOG_CHUNK; 89 continue; 90 } 91 /* Data must be read atomically. We don't really need barrier semantics 92 * but it's easier to use atomic_* than roll our own. */ 93 log = qatomic_xchg(from, 0); 94 while (log) { 95 int bit = ctzl(log); 96 hwaddr page_addr; 97 hwaddr section_offset; 98 hwaddr mr_offset; 99 page_addr = addr + bit * VHOST_LOG_PAGE; 100 section_offset = page_addr - section->offset_within_address_space; 101 mr_offset = section_offset + section->offset_within_region; 102 memory_region_set_dirty(section->mr, mr_offset, VHOST_LOG_PAGE); 103 log &= ~(0x1ull << bit); 104 } 105 addr += VHOST_LOG_CHUNK; 106 } 107 } 108 109 bool vhost_dev_has_iommu(struct vhost_dev *dev) 110 { 111 VirtIODevice *vdev = dev->vdev; 112 113 /* 114 * For vhost, VIRTIO_F_IOMMU_PLATFORM means the backend support 115 * incremental memory mapping API via IOTLB API. For platform that 116 * does not have IOMMU, there's no need to enable this feature 117 * which may cause unnecessary IOTLB miss/update transactions. 118 */ 119 if (vdev) { 120 return virtio_bus_device_iommu_enabled(vdev) && 121 virtio_host_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM); 122 } else { 123 return false; 124 } 125 } 126 127 static int vhost_sync_dirty_bitmap(struct vhost_dev *dev, 128 MemoryRegionSection *section, 129 hwaddr first, 130 hwaddr last) 131 { 132 int i; 133 hwaddr start_addr; 134 hwaddr end_addr; 135 136 if (!dev->log_enabled || !dev->started) { 137 return 0; 138 } 139 start_addr = section->offset_within_address_space; 140 end_addr = range_get_last(start_addr, int128_get64(section->size)); 141 start_addr = MAX(first, start_addr); 142 end_addr = MIN(last, end_addr); 143 144 for (i = 0; i < dev->mem->nregions; ++i) { 145 struct vhost_memory_region *reg = dev->mem->regions + i; 146 vhost_dev_sync_region(dev, section, start_addr, end_addr, 147 reg->guest_phys_addr, 148 range_get_last(reg->guest_phys_addr, 149 reg->memory_size)); 150 } 151 for (i = 0; i < dev->nvqs; ++i) { 152 struct vhost_virtqueue *vq = dev->vqs + i; 153 154 if (!vq->used_phys && !vq->used_size) { 155 continue; 156 } 157 158 if (vhost_dev_has_iommu(dev)) { 159 IOMMUTLBEntry iotlb; 160 hwaddr used_phys = vq->used_phys, used_size = vq->used_size; 161 hwaddr phys, s, offset; 162 163 while (used_size) { 164 rcu_read_lock(); 165 iotlb = address_space_get_iotlb_entry(dev->vdev->dma_as, 166 used_phys, 167 true, 168 MEMTXATTRS_UNSPECIFIED); 169 rcu_read_unlock(); 170 171 if (!iotlb.target_as) { 172 qemu_log_mask(LOG_GUEST_ERROR, "translation " 173 "failure for used_iova %"PRIx64"\n", 174 used_phys); 175 return -EINVAL; 176 } 177 178 offset = used_phys & iotlb.addr_mask; 179 phys = iotlb.translated_addr + offset; 180 181 /* 182 * Distance from start of used ring until last byte of 183 * IOMMU page. 184 */ 185 s = iotlb.addr_mask - offset; 186 /* 187 * Size of used ring, or of the part of it until end 188 * of IOMMU page. To avoid zero result, do the adding 189 * outside of MIN(). 190 */ 191 s = MIN(s, used_size - 1) + 1; 192 193 vhost_dev_sync_region(dev, section, start_addr, end_addr, phys, 194 range_get_last(phys, s)); 195 used_size -= s; 196 used_phys += s; 197 } 198 } else { 199 vhost_dev_sync_region(dev, section, start_addr, 200 end_addr, vq->used_phys, 201 range_get_last(vq->used_phys, vq->used_size)); 202 } 203 } 204 return 0; 205 } 206 207 static void vhost_log_sync(MemoryListener *listener, 208 MemoryRegionSection *section) 209 { 210 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 211 memory_listener); 212 vhost_sync_dirty_bitmap(dev, section, 0x0, ~0x0ULL); 213 } 214 215 static void vhost_log_sync_range(struct vhost_dev *dev, 216 hwaddr first, hwaddr last) 217 { 218 int i; 219 /* FIXME: this is N^2 in number of sections */ 220 for (i = 0; i < dev->n_mem_sections; ++i) { 221 MemoryRegionSection *section = &dev->mem_sections[i]; 222 vhost_sync_dirty_bitmap(dev, section, first, last); 223 } 224 } 225 226 static uint64_t vhost_get_log_size(struct vhost_dev *dev) 227 { 228 uint64_t log_size = 0; 229 int i; 230 for (i = 0; i < dev->mem->nregions; ++i) { 231 struct vhost_memory_region *reg = dev->mem->regions + i; 232 uint64_t last = range_get_last(reg->guest_phys_addr, 233 reg->memory_size); 234 log_size = MAX(log_size, last / VHOST_LOG_CHUNK + 1); 235 } 236 return log_size; 237 } 238 239 static int vhost_set_backend_type(struct vhost_dev *dev, 240 VhostBackendType backend_type) 241 { 242 int r = 0; 243 244 switch (backend_type) { 245 #ifdef CONFIG_VHOST_KERNEL 246 case VHOST_BACKEND_TYPE_KERNEL: 247 dev->vhost_ops = &kernel_ops; 248 break; 249 #endif 250 #ifdef CONFIG_VHOST_USER 251 case VHOST_BACKEND_TYPE_USER: 252 dev->vhost_ops = &user_ops; 253 break; 254 #endif 255 #ifdef CONFIG_VHOST_VDPA 256 case VHOST_BACKEND_TYPE_VDPA: 257 dev->vhost_ops = &vdpa_ops; 258 break; 259 #endif 260 default: 261 error_report("Unknown vhost backend type"); 262 r = -1; 263 } 264 265 return r; 266 } 267 268 static struct vhost_log *vhost_log_alloc(uint64_t size, bool share) 269 { 270 Error *err = NULL; 271 struct vhost_log *log; 272 uint64_t logsize = size * sizeof(*(log->log)); 273 int fd = -1; 274 275 log = g_new0(struct vhost_log, 1); 276 if (share) { 277 log->log = qemu_memfd_alloc("vhost-log", logsize, 278 F_SEAL_GROW | F_SEAL_SHRINK | F_SEAL_SEAL, 279 &fd, &err); 280 if (err) { 281 error_report_err(err); 282 g_free(log); 283 return NULL; 284 } 285 memset(log->log, 0, logsize); 286 } else { 287 log->log = g_malloc0(logsize); 288 } 289 290 log->size = size; 291 log->refcnt = 1; 292 log->fd = fd; 293 294 return log; 295 } 296 297 static struct vhost_log *vhost_log_get(uint64_t size, bool share) 298 { 299 struct vhost_log *log = share ? vhost_log_shm : vhost_log; 300 301 if (!log || log->size != size) { 302 log = vhost_log_alloc(size, share); 303 if (share) { 304 vhost_log_shm = log; 305 } else { 306 vhost_log = log; 307 } 308 } else { 309 ++log->refcnt; 310 } 311 312 return log; 313 } 314 315 static void vhost_log_put(struct vhost_dev *dev, bool sync) 316 { 317 struct vhost_log *log = dev->log; 318 319 if (!log) { 320 return; 321 } 322 323 --log->refcnt; 324 if (log->refcnt == 0) { 325 /* Sync only the range covered by the old log */ 326 if (dev->log_size && sync) { 327 vhost_log_sync_range(dev, 0, dev->log_size * VHOST_LOG_CHUNK - 1); 328 } 329 330 if (vhost_log == log) { 331 g_free(log->log); 332 vhost_log = NULL; 333 } else if (vhost_log_shm == log) { 334 qemu_memfd_free(log->log, log->size * sizeof(*(log->log)), 335 log->fd); 336 vhost_log_shm = NULL; 337 } 338 339 g_free(log); 340 } 341 342 dev->log = NULL; 343 dev->log_size = 0; 344 } 345 346 static bool vhost_dev_log_is_shared(struct vhost_dev *dev) 347 { 348 return dev->vhost_ops->vhost_requires_shm_log && 349 dev->vhost_ops->vhost_requires_shm_log(dev); 350 } 351 352 static inline void vhost_dev_log_resize(struct vhost_dev *dev, uint64_t size) 353 { 354 struct vhost_log *log = vhost_log_get(size, vhost_dev_log_is_shared(dev)); 355 uint64_t log_base = (uintptr_t)log->log; 356 int r; 357 358 /* inform backend of log switching, this must be done before 359 releasing the current log, to ensure no logging is lost */ 360 r = dev->vhost_ops->vhost_set_log_base(dev, log_base, log); 361 if (r < 0) { 362 VHOST_OPS_DEBUG(r, "vhost_set_log_base failed"); 363 } 364 365 vhost_log_put(dev, true); 366 dev->log = log; 367 dev->log_size = size; 368 } 369 370 static void *vhost_memory_map(struct vhost_dev *dev, hwaddr addr, 371 hwaddr *plen, bool is_write) 372 { 373 if (!vhost_dev_has_iommu(dev)) { 374 return cpu_physical_memory_map(addr, plen, is_write); 375 } else { 376 return (void *)(uintptr_t)addr; 377 } 378 } 379 380 static void vhost_memory_unmap(struct vhost_dev *dev, void *buffer, 381 hwaddr len, int is_write, 382 hwaddr access_len) 383 { 384 if (!vhost_dev_has_iommu(dev)) { 385 cpu_physical_memory_unmap(buffer, len, is_write, access_len); 386 } 387 } 388 389 static int vhost_verify_ring_part_mapping(void *ring_hva, 390 uint64_t ring_gpa, 391 uint64_t ring_size, 392 void *reg_hva, 393 uint64_t reg_gpa, 394 uint64_t reg_size) 395 { 396 uint64_t hva_ring_offset; 397 uint64_t ring_last = range_get_last(ring_gpa, ring_size); 398 uint64_t reg_last = range_get_last(reg_gpa, reg_size); 399 400 if (ring_last < reg_gpa || ring_gpa > reg_last) { 401 return 0; 402 } 403 /* check that whole ring's is mapped */ 404 if (ring_last > reg_last) { 405 return -ENOMEM; 406 } 407 /* check that ring's MemoryRegion wasn't replaced */ 408 hva_ring_offset = ring_gpa - reg_gpa; 409 if (ring_hva != reg_hva + hva_ring_offset) { 410 return -EBUSY; 411 } 412 413 return 0; 414 } 415 416 static int vhost_verify_ring_mappings(struct vhost_dev *dev, 417 void *reg_hva, 418 uint64_t reg_gpa, 419 uint64_t reg_size) 420 { 421 int i, j; 422 int r = 0; 423 const char *part_name[] = { 424 "descriptor table", 425 "available ring", 426 "used ring" 427 }; 428 429 if (vhost_dev_has_iommu(dev)) { 430 return 0; 431 } 432 433 for (i = 0; i < dev->nvqs; ++i) { 434 struct vhost_virtqueue *vq = dev->vqs + i; 435 436 if (vq->desc_phys == 0) { 437 continue; 438 } 439 440 j = 0; 441 r = vhost_verify_ring_part_mapping( 442 vq->desc, vq->desc_phys, vq->desc_size, 443 reg_hva, reg_gpa, reg_size); 444 if (r) { 445 break; 446 } 447 448 j++; 449 r = vhost_verify_ring_part_mapping( 450 vq->avail, vq->avail_phys, vq->avail_size, 451 reg_hva, reg_gpa, reg_size); 452 if (r) { 453 break; 454 } 455 456 j++; 457 r = vhost_verify_ring_part_mapping( 458 vq->used, vq->used_phys, vq->used_size, 459 reg_hva, reg_gpa, reg_size); 460 if (r) { 461 break; 462 } 463 } 464 465 if (r == -ENOMEM) { 466 error_report("Unable to map %s for ring %d", part_name[j], i); 467 } else if (r == -EBUSY) { 468 error_report("%s relocated for ring %d", part_name[j], i); 469 } 470 return r; 471 } 472 473 /* 474 * vhost_section: identify sections needed for vhost access 475 * 476 * We only care about RAM sections here (where virtqueue and guest 477 * internals accessed by virtio might live). If we find one we still 478 * allow the backend to potentially filter it out of our list. 479 */ 480 static bool vhost_section(struct vhost_dev *dev, MemoryRegionSection *section) 481 { 482 MemoryRegion *mr = section->mr; 483 484 if (memory_region_is_ram(mr) && !memory_region_is_rom(mr)) { 485 uint8_t dirty_mask = memory_region_get_dirty_log_mask(mr); 486 uint8_t handled_dirty; 487 488 /* 489 * Kernel based vhost doesn't handle any block which is doing 490 * dirty-tracking other than migration for which it has 491 * specific logging support. However for TCG the kernel never 492 * gets involved anyway so we can also ignore it's 493 * self-modiying code detection flags. However a vhost-user 494 * client could still confuse a TCG guest if it re-writes 495 * executable memory that has already been translated. 496 */ 497 handled_dirty = (1 << DIRTY_MEMORY_MIGRATION) | 498 (1 << DIRTY_MEMORY_CODE); 499 500 if (dirty_mask & ~handled_dirty) { 501 trace_vhost_reject_section(mr->name, 1); 502 return false; 503 } 504 505 if (dev->vhost_ops->vhost_backend_mem_section_filter && 506 !dev->vhost_ops->vhost_backend_mem_section_filter(dev, section)) { 507 trace_vhost_reject_section(mr->name, 2); 508 return false; 509 } 510 511 trace_vhost_section(mr->name); 512 return true; 513 } else { 514 trace_vhost_reject_section(mr->name, 3); 515 return false; 516 } 517 } 518 519 static void vhost_begin(MemoryListener *listener) 520 { 521 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 522 memory_listener); 523 dev->tmp_sections = NULL; 524 dev->n_tmp_sections = 0; 525 } 526 527 static void vhost_commit(MemoryListener *listener) 528 { 529 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 530 memory_listener); 531 MemoryRegionSection *old_sections; 532 int n_old_sections; 533 uint64_t log_size; 534 size_t regions_size; 535 int r; 536 int i; 537 bool changed = false; 538 539 /* Note we can be called before the device is started, but then 540 * starting the device calls set_mem_table, so we need to have 541 * built the data structures. 542 */ 543 old_sections = dev->mem_sections; 544 n_old_sections = dev->n_mem_sections; 545 dev->mem_sections = dev->tmp_sections; 546 dev->n_mem_sections = dev->n_tmp_sections; 547 548 if (dev->n_mem_sections != n_old_sections) { 549 changed = true; 550 } else { 551 /* Same size, lets check the contents */ 552 for (int i = 0; i < n_old_sections; i++) { 553 if (!MemoryRegionSection_eq(&old_sections[i], 554 &dev->mem_sections[i])) { 555 changed = true; 556 break; 557 } 558 } 559 } 560 561 trace_vhost_commit(dev->started, changed); 562 if (!changed) { 563 goto out; 564 } 565 566 /* Rebuild the regions list from the new sections list */ 567 regions_size = offsetof(struct vhost_memory, regions) + 568 dev->n_mem_sections * sizeof dev->mem->regions[0]; 569 dev->mem = g_realloc(dev->mem, regions_size); 570 dev->mem->nregions = dev->n_mem_sections; 571 used_memslots = dev->mem->nregions; 572 for (i = 0; i < dev->n_mem_sections; i++) { 573 struct vhost_memory_region *cur_vmr = dev->mem->regions + i; 574 struct MemoryRegionSection *mrs = dev->mem_sections + i; 575 576 cur_vmr->guest_phys_addr = mrs->offset_within_address_space; 577 cur_vmr->memory_size = int128_get64(mrs->size); 578 cur_vmr->userspace_addr = 579 (uintptr_t)memory_region_get_ram_ptr(mrs->mr) + 580 mrs->offset_within_region; 581 cur_vmr->flags_padding = 0; 582 } 583 584 if (!dev->started) { 585 goto out; 586 } 587 588 for (i = 0; i < dev->mem->nregions; i++) { 589 if (vhost_verify_ring_mappings(dev, 590 (void *)(uintptr_t)dev->mem->regions[i].userspace_addr, 591 dev->mem->regions[i].guest_phys_addr, 592 dev->mem->regions[i].memory_size)) { 593 error_report("Verify ring failure on region %d", i); 594 abort(); 595 } 596 } 597 598 if (!dev->log_enabled) { 599 r = dev->vhost_ops->vhost_set_mem_table(dev, dev->mem); 600 if (r < 0) { 601 VHOST_OPS_DEBUG(r, "vhost_set_mem_table failed"); 602 } 603 goto out; 604 } 605 log_size = vhost_get_log_size(dev); 606 /* We allocate an extra 4K bytes to log, 607 * to reduce the * number of reallocations. */ 608 #define VHOST_LOG_BUFFER (0x1000 / sizeof *dev->log) 609 /* To log more, must increase log size before table update. */ 610 if (dev->log_size < log_size) { 611 vhost_dev_log_resize(dev, log_size + VHOST_LOG_BUFFER); 612 } 613 r = dev->vhost_ops->vhost_set_mem_table(dev, dev->mem); 614 if (r < 0) { 615 VHOST_OPS_DEBUG(r, "vhost_set_mem_table failed"); 616 } 617 /* To log less, can only decrease log size after table update. */ 618 if (dev->log_size > log_size + VHOST_LOG_BUFFER) { 619 vhost_dev_log_resize(dev, log_size); 620 } 621 622 out: 623 /* Deref the old list of sections, this must happen _after_ the 624 * vhost_set_mem_table to ensure the client isn't still using the 625 * section we're about to unref. 626 */ 627 while (n_old_sections--) { 628 memory_region_unref(old_sections[n_old_sections].mr); 629 } 630 g_free(old_sections); 631 return; 632 } 633 634 /* Adds the section data to the tmp_section structure. 635 * It relies on the listener calling us in memory address order 636 * and for each region (via the _add and _nop methods) to 637 * join neighbours. 638 */ 639 static void vhost_region_add_section(struct vhost_dev *dev, 640 MemoryRegionSection *section) 641 { 642 bool need_add = true; 643 uint64_t mrs_size = int128_get64(section->size); 644 uint64_t mrs_gpa = section->offset_within_address_space; 645 uintptr_t mrs_host = (uintptr_t)memory_region_get_ram_ptr(section->mr) + 646 section->offset_within_region; 647 RAMBlock *mrs_rb = section->mr->ram_block; 648 649 trace_vhost_region_add_section(section->mr->name, mrs_gpa, mrs_size, 650 mrs_host); 651 652 if (dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER) { 653 /* Round the section to it's page size */ 654 /* First align the start down to a page boundary */ 655 size_t mrs_page = qemu_ram_pagesize(mrs_rb); 656 uint64_t alignage = mrs_host & (mrs_page - 1); 657 if (alignage) { 658 mrs_host -= alignage; 659 mrs_size += alignage; 660 mrs_gpa -= alignage; 661 } 662 /* Now align the size up to a page boundary */ 663 alignage = mrs_size & (mrs_page - 1); 664 if (alignage) { 665 mrs_size += mrs_page - alignage; 666 } 667 trace_vhost_region_add_section_aligned(section->mr->name, mrs_gpa, 668 mrs_size, mrs_host); 669 } 670 671 if (dev->n_tmp_sections) { 672 /* Since we already have at least one section, lets see if 673 * this extends it; since we're scanning in order, we only 674 * have to look at the last one, and the FlatView that calls 675 * us shouldn't have overlaps. 676 */ 677 MemoryRegionSection *prev_sec = dev->tmp_sections + 678 (dev->n_tmp_sections - 1); 679 uint64_t prev_gpa_start = prev_sec->offset_within_address_space; 680 uint64_t prev_size = int128_get64(prev_sec->size); 681 uint64_t prev_gpa_end = range_get_last(prev_gpa_start, prev_size); 682 uint64_t prev_host_start = 683 (uintptr_t)memory_region_get_ram_ptr(prev_sec->mr) + 684 prev_sec->offset_within_region; 685 uint64_t prev_host_end = range_get_last(prev_host_start, prev_size); 686 687 if (mrs_gpa <= (prev_gpa_end + 1)) { 688 /* OK, looks like overlapping/intersecting - it's possible that 689 * the rounding to page sizes has made them overlap, but they should 690 * match up in the same RAMBlock if they do. 691 */ 692 if (mrs_gpa < prev_gpa_start) { 693 error_report("%s:Section '%s' rounded to %"PRIx64 694 " prior to previous '%s' %"PRIx64, 695 __func__, section->mr->name, mrs_gpa, 696 prev_sec->mr->name, prev_gpa_start); 697 /* A way to cleanly fail here would be better */ 698 return; 699 } 700 /* Offset from the start of the previous GPA to this GPA */ 701 size_t offset = mrs_gpa - prev_gpa_start; 702 703 if (prev_host_start + offset == mrs_host && 704 section->mr == prev_sec->mr && 705 (!dev->vhost_ops->vhost_backend_can_merge || 706 dev->vhost_ops->vhost_backend_can_merge(dev, 707 mrs_host, mrs_size, 708 prev_host_start, prev_size))) { 709 uint64_t max_end = MAX(prev_host_end, mrs_host + mrs_size); 710 need_add = false; 711 prev_sec->offset_within_address_space = 712 MIN(prev_gpa_start, mrs_gpa); 713 prev_sec->offset_within_region = 714 MIN(prev_host_start, mrs_host) - 715 (uintptr_t)memory_region_get_ram_ptr(prev_sec->mr); 716 prev_sec->size = int128_make64(max_end - MIN(prev_host_start, 717 mrs_host)); 718 trace_vhost_region_add_section_merge(section->mr->name, 719 int128_get64(prev_sec->size), 720 prev_sec->offset_within_address_space, 721 prev_sec->offset_within_region); 722 } else { 723 /* adjoining regions are fine, but overlapping ones with 724 * different blocks/offsets shouldn't happen 725 */ 726 if (mrs_gpa != prev_gpa_end + 1) { 727 error_report("%s: Overlapping but not coherent sections " 728 "at %"PRIx64, 729 __func__, mrs_gpa); 730 return; 731 } 732 } 733 } 734 } 735 736 if (need_add) { 737 ++dev->n_tmp_sections; 738 dev->tmp_sections = g_renew(MemoryRegionSection, dev->tmp_sections, 739 dev->n_tmp_sections); 740 dev->tmp_sections[dev->n_tmp_sections - 1] = *section; 741 /* The flatview isn't stable and we don't use it, making it NULL 742 * means we can memcmp the list. 743 */ 744 dev->tmp_sections[dev->n_tmp_sections - 1].fv = NULL; 745 memory_region_ref(section->mr); 746 } 747 } 748 749 /* Used for both add and nop callbacks */ 750 static void vhost_region_addnop(MemoryListener *listener, 751 MemoryRegionSection *section) 752 { 753 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 754 memory_listener); 755 756 if (!vhost_section(dev, section)) { 757 return; 758 } 759 vhost_region_add_section(dev, section); 760 } 761 762 static void vhost_iommu_unmap_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb) 763 { 764 struct vhost_iommu *iommu = container_of(n, struct vhost_iommu, n); 765 struct vhost_dev *hdev = iommu->hdev; 766 hwaddr iova = iotlb->iova + iommu->iommu_offset; 767 768 if (vhost_backend_invalidate_device_iotlb(hdev, iova, 769 iotlb->addr_mask + 1)) { 770 error_report("Fail to invalidate device iotlb"); 771 } 772 } 773 774 static void vhost_iommu_region_add(MemoryListener *listener, 775 MemoryRegionSection *section) 776 { 777 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 778 iommu_listener); 779 struct vhost_iommu *iommu; 780 Int128 end; 781 int iommu_idx; 782 IOMMUMemoryRegion *iommu_mr; 783 int ret; 784 785 if (!memory_region_is_iommu(section->mr)) { 786 return; 787 } 788 789 iommu_mr = IOMMU_MEMORY_REGION(section->mr); 790 791 iommu = g_malloc0(sizeof(*iommu)); 792 end = int128_add(int128_make64(section->offset_within_region), 793 section->size); 794 end = int128_sub(end, int128_one()); 795 iommu_idx = memory_region_iommu_attrs_to_index(iommu_mr, 796 MEMTXATTRS_UNSPECIFIED); 797 iommu_notifier_init(&iommu->n, vhost_iommu_unmap_notify, 798 IOMMU_NOTIFIER_DEVIOTLB_UNMAP, 799 section->offset_within_region, 800 int128_get64(end), 801 iommu_idx); 802 iommu->mr = section->mr; 803 iommu->iommu_offset = section->offset_within_address_space - 804 section->offset_within_region; 805 iommu->hdev = dev; 806 ret = memory_region_register_iommu_notifier(section->mr, &iommu->n, NULL); 807 if (ret) { 808 /* 809 * Some vIOMMUs do not support dev-iotlb yet. If so, try to use the 810 * UNMAP legacy message 811 */ 812 iommu->n.notifier_flags = IOMMU_NOTIFIER_UNMAP; 813 memory_region_register_iommu_notifier(section->mr, &iommu->n, 814 &error_fatal); 815 } 816 QLIST_INSERT_HEAD(&dev->iommu_list, iommu, iommu_next); 817 /* TODO: can replay help performance here? */ 818 } 819 820 static void vhost_iommu_region_del(MemoryListener *listener, 821 MemoryRegionSection *section) 822 { 823 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 824 iommu_listener); 825 struct vhost_iommu *iommu; 826 827 if (!memory_region_is_iommu(section->mr)) { 828 return; 829 } 830 831 QLIST_FOREACH(iommu, &dev->iommu_list, iommu_next) { 832 if (iommu->mr == section->mr && 833 iommu->n.start == section->offset_within_region) { 834 memory_region_unregister_iommu_notifier(iommu->mr, 835 &iommu->n); 836 QLIST_REMOVE(iommu, iommu_next); 837 g_free(iommu); 838 break; 839 } 840 } 841 } 842 843 static int vhost_virtqueue_set_addr(struct vhost_dev *dev, 844 struct vhost_virtqueue *vq, 845 unsigned idx, bool enable_log) 846 { 847 struct vhost_vring_addr addr; 848 int r; 849 memset(&addr, 0, sizeof(struct vhost_vring_addr)); 850 851 if (dev->vhost_ops->vhost_vq_get_addr) { 852 r = dev->vhost_ops->vhost_vq_get_addr(dev, &addr, vq); 853 if (r < 0) { 854 VHOST_OPS_DEBUG(r, "vhost_vq_get_addr failed"); 855 return r; 856 } 857 } else { 858 addr.desc_user_addr = (uint64_t)(unsigned long)vq->desc; 859 addr.avail_user_addr = (uint64_t)(unsigned long)vq->avail; 860 addr.used_user_addr = (uint64_t)(unsigned long)vq->used; 861 } 862 addr.index = idx; 863 addr.log_guest_addr = vq->used_phys; 864 addr.flags = enable_log ? (1 << VHOST_VRING_F_LOG) : 0; 865 r = dev->vhost_ops->vhost_set_vring_addr(dev, &addr); 866 if (r < 0) { 867 VHOST_OPS_DEBUG(r, "vhost_set_vring_addr failed"); 868 } 869 return r; 870 } 871 872 static int vhost_dev_set_features(struct vhost_dev *dev, 873 bool enable_log) 874 { 875 uint64_t features = dev->acked_features; 876 int r; 877 if (enable_log) { 878 features |= 0x1ULL << VHOST_F_LOG_ALL; 879 } 880 if (!vhost_dev_has_iommu(dev)) { 881 features &= ~(0x1ULL << VIRTIO_F_IOMMU_PLATFORM); 882 } 883 if (dev->vhost_ops->vhost_force_iommu) { 884 if (dev->vhost_ops->vhost_force_iommu(dev) == true) { 885 features |= 0x1ULL << VIRTIO_F_IOMMU_PLATFORM; 886 } 887 } 888 r = dev->vhost_ops->vhost_set_features(dev, features); 889 if (r < 0) { 890 VHOST_OPS_DEBUG(r, "vhost_set_features failed"); 891 goto out; 892 } 893 if (dev->vhost_ops->vhost_set_backend_cap) { 894 r = dev->vhost_ops->vhost_set_backend_cap(dev); 895 if (r < 0) { 896 VHOST_OPS_DEBUG(r, "vhost_set_backend_cap failed"); 897 goto out; 898 } 899 } 900 901 out: 902 return r; 903 } 904 905 static int vhost_dev_set_log(struct vhost_dev *dev, bool enable_log) 906 { 907 int r, i, idx; 908 hwaddr addr; 909 910 r = vhost_dev_set_features(dev, enable_log); 911 if (r < 0) { 912 goto err_features; 913 } 914 for (i = 0; i < dev->nvqs; ++i) { 915 idx = dev->vhost_ops->vhost_get_vq_index(dev, dev->vq_index + i); 916 addr = virtio_queue_get_desc_addr(dev->vdev, idx); 917 if (!addr) { 918 /* 919 * The queue might not be ready for start. If this 920 * is the case there is no reason to continue the process. 921 * The similar logic is used by the vhost_virtqueue_start() 922 * routine. 923 */ 924 continue; 925 } 926 r = vhost_virtqueue_set_addr(dev, dev->vqs + i, idx, 927 enable_log); 928 if (r < 0) { 929 goto err_vq; 930 } 931 } 932 return 0; 933 err_vq: 934 for (; i >= 0; --i) { 935 idx = dev->vhost_ops->vhost_get_vq_index(dev, dev->vq_index + i); 936 addr = virtio_queue_get_desc_addr(dev->vdev, idx); 937 if (!addr) { 938 continue; 939 } 940 vhost_virtqueue_set_addr(dev, dev->vqs + i, idx, 941 dev->log_enabled); 942 } 943 vhost_dev_set_features(dev, dev->log_enabled); 944 err_features: 945 return r; 946 } 947 948 static int vhost_migration_log(MemoryListener *listener, bool enable) 949 { 950 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 951 memory_listener); 952 int r; 953 if (enable == dev->log_enabled) { 954 return 0; 955 } 956 if (!dev->started) { 957 dev->log_enabled = enable; 958 return 0; 959 } 960 961 r = 0; 962 if (!enable) { 963 r = vhost_dev_set_log(dev, false); 964 if (r < 0) { 965 goto check_dev_state; 966 } 967 vhost_log_put(dev, false); 968 } else { 969 vhost_dev_log_resize(dev, vhost_get_log_size(dev)); 970 r = vhost_dev_set_log(dev, true); 971 if (r < 0) { 972 goto check_dev_state; 973 } 974 } 975 976 check_dev_state: 977 dev->log_enabled = enable; 978 /* 979 * vhost-user-* devices could change their state during log 980 * initialization due to disconnect. So check dev state after 981 * vhost communication. 982 */ 983 if (!dev->started) { 984 /* 985 * Since device is in the stopped state, it is okay for 986 * migration. Return success. 987 */ 988 r = 0; 989 } 990 if (r) { 991 /* An error occurred. */ 992 dev->log_enabled = false; 993 } 994 995 return r; 996 } 997 998 static void vhost_log_global_start(MemoryListener *listener) 999 { 1000 int r; 1001 1002 r = vhost_migration_log(listener, true); 1003 if (r < 0) { 1004 abort(); 1005 } 1006 } 1007 1008 static void vhost_log_global_stop(MemoryListener *listener) 1009 { 1010 int r; 1011 1012 r = vhost_migration_log(listener, false); 1013 if (r < 0) { 1014 abort(); 1015 } 1016 } 1017 1018 static void vhost_log_start(MemoryListener *listener, 1019 MemoryRegionSection *section, 1020 int old, int new) 1021 { 1022 /* FIXME: implement */ 1023 } 1024 1025 static void vhost_log_stop(MemoryListener *listener, 1026 MemoryRegionSection *section, 1027 int old, int new) 1028 { 1029 /* FIXME: implement */ 1030 } 1031 1032 /* The vhost driver natively knows how to handle the vrings of non 1033 * cross-endian legacy devices and modern devices. Only legacy devices 1034 * exposed to a bi-endian guest may require the vhost driver to use a 1035 * specific endianness. 1036 */ 1037 static inline bool vhost_needs_vring_endian(VirtIODevice *vdev) 1038 { 1039 if (virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) { 1040 return false; 1041 } 1042 #if HOST_BIG_ENDIAN 1043 return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_LITTLE; 1044 #else 1045 return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG; 1046 #endif 1047 } 1048 1049 static int vhost_virtqueue_set_vring_endian_legacy(struct vhost_dev *dev, 1050 bool is_big_endian, 1051 int vhost_vq_index) 1052 { 1053 int r; 1054 struct vhost_vring_state s = { 1055 .index = vhost_vq_index, 1056 .num = is_big_endian 1057 }; 1058 1059 r = dev->vhost_ops->vhost_set_vring_endian(dev, &s); 1060 if (r < 0) { 1061 VHOST_OPS_DEBUG(r, "vhost_set_vring_endian failed"); 1062 } 1063 return r; 1064 } 1065 1066 static int vhost_memory_region_lookup(struct vhost_dev *hdev, 1067 uint64_t gpa, uint64_t *uaddr, 1068 uint64_t *len) 1069 { 1070 int i; 1071 1072 for (i = 0; i < hdev->mem->nregions; i++) { 1073 struct vhost_memory_region *reg = hdev->mem->regions + i; 1074 1075 if (gpa >= reg->guest_phys_addr && 1076 reg->guest_phys_addr + reg->memory_size > gpa) { 1077 *uaddr = reg->userspace_addr + gpa - reg->guest_phys_addr; 1078 *len = reg->guest_phys_addr + reg->memory_size - gpa; 1079 return 0; 1080 } 1081 } 1082 1083 return -EFAULT; 1084 } 1085 1086 int vhost_device_iotlb_miss(struct vhost_dev *dev, uint64_t iova, int write) 1087 { 1088 IOMMUTLBEntry iotlb; 1089 uint64_t uaddr, len; 1090 int ret = -EFAULT; 1091 1092 RCU_READ_LOCK_GUARD(); 1093 1094 trace_vhost_iotlb_miss(dev, 1); 1095 1096 iotlb = address_space_get_iotlb_entry(dev->vdev->dma_as, 1097 iova, write, 1098 MEMTXATTRS_UNSPECIFIED); 1099 if (iotlb.target_as != NULL) { 1100 ret = vhost_memory_region_lookup(dev, iotlb.translated_addr, 1101 &uaddr, &len); 1102 if (ret) { 1103 trace_vhost_iotlb_miss(dev, 3); 1104 error_report("Fail to lookup the translated address " 1105 "%"PRIx64, iotlb.translated_addr); 1106 goto out; 1107 } 1108 1109 len = MIN(iotlb.addr_mask + 1, len); 1110 iova = iova & ~iotlb.addr_mask; 1111 1112 ret = vhost_backend_update_device_iotlb(dev, iova, uaddr, 1113 len, iotlb.perm); 1114 if (ret) { 1115 trace_vhost_iotlb_miss(dev, 4); 1116 error_report("Fail to update device iotlb"); 1117 goto out; 1118 } 1119 } 1120 1121 trace_vhost_iotlb_miss(dev, 2); 1122 1123 out: 1124 return ret; 1125 } 1126 1127 int vhost_virtqueue_start(struct vhost_dev *dev, 1128 struct VirtIODevice *vdev, 1129 struct vhost_virtqueue *vq, 1130 unsigned idx) 1131 { 1132 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); 1133 VirtioBusState *vbus = VIRTIO_BUS(qbus); 1134 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(vbus); 1135 hwaddr s, l, a; 1136 int r; 1137 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, idx); 1138 struct vhost_vring_file file = { 1139 .index = vhost_vq_index 1140 }; 1141 struct vhost_vring_state state = { 1142 .index = vhost_vq_index 1143 }; 1144 struct VirtQueue *vvq = virtio_get_queue(vdev, idx); 1145 1146 a = virtio_queue_get_desc_addr(vdev, idx); 1147 if (a == 0) { 1148 /* Queue might not be ready for start */ 1149 return 0; 1150 } 1151 1152 vq->num = state.num = virtio_queue_get_num(vdev, idx); 1153 r = dev->vhost_ops->vhost_set_vring_num(dev, &state); 1154 if (r) { 1155 VHOST_OPS_DEBUG(r, "vhost_set_vring_num failed"); 1156 return r; 1157 } 1158 1159 state.num = virtio_queue_get_last_avail_idx(vdev, idx); 1160 r = dev->vhost_ops->vhost_set_vring_base(dev, &state); 1161 if (r) { 1162 VHOST_OPS_DEBUG(r, "vhost_set_vring_base failed"); 1163 return r; 1164 } 1165 1166 if (vhost_needs_vring_endian(vdev)) { 1167 r = vhost_virtqueue_set_vring_endian_legacy(dev, 1168 virtio_is_big_endian(vdev), 1169 vhost_vq_index); 1170 if (r) { 1171 return r; 1172 } 1173 } 1174 1175 vq->desc_size = s = l = virtio_queue_get_desc_size(vdev, idx); 1176 vq->desc_phys = a; 1177 vq->desc = vhost_memory_map(dev, a, &l, false); 1178 if (!vq->desc || l != s) { 1179 r = -ENOMEM; 1180 goto fail_alloc_desc; 1181 } 1182 vq->avail_size = s = l = virtio_queue_get_avail_size(vdev, idx); 1183 vq->avail_phys = a = virtio_queue_get_avail_addr(vdev, idx); 1184 vq->avail = vhost_memory_map(dev, a, &l, false); 1185 if (!vq->avail || l != s) { 1186 r = -ENOMEM; 1187 goto fail_alloc_avail; 1188 } 1189 vq->used_size = s = l = virtio_queue_get_used_size(vdev, idx); 1190 vq->used_phys = a = virtio_queue_get_used_addr(vdev, idx); 1191 vq->used = vhost_memory_map(dev, a, &l, true); 1192 if (!vq->used || l != s) { 1193 r = -ENOMEM; 1194 goto fail_alloc_used; 1195 } 1196 1197 r = vhost_virtqueue_set_addr(dev, vq, vhost_vq_index, dev->log_enabled); 1198 if (r < 0) { 1199 goto fail_alloc; 1200 } 1201 1202 file.fd = event_notifier_get_fd(virtio_queue_get_host_notifier(vvq)); 1203 r = dev->vhost_ops->vhost_set_vring_kick(dev, &file); 1204 if (r) { 1205 VHOST_OPS_DEBUG(r, "vhost_set_vring_kick failed"); 1206 goto fail_kick; 1207 } 1208 1209 /* Clear and discard previous events if any. */ 1210 event_notifier_test_and_clear(&vq->masked_notifier); 1211 1212 /* Init vring in unmasked state, unless guest_notifier_mask 1213 * will do it later. 1214 */ 1215 if (!vdev->use_guest_notifier_mask) { 1216 /* TODO: check and handle errors. */ 1217 vhost_virtqueue_mask(dev, vdev, idx, false); 1218 } 1219 1220 if (k->query_guest_notifiers && 1221 k->query_guest_notifiers(qbus->parent) && 1222 virtio_queue_vector(vdev, idx) == VIRTIO_NO_VECTOR) { 1223 file.fd = -1; 1224 r = dev->vhost_ops->vhost_set_vring_call(dev, &file); 1225 if (r) { 1226 goto fail_vector; 1227 } 1228 } 1229 1230 return 0; 1231 1232 fail_vector: 1233 fail_kick: 1234 fail_alloc: 1235 vhost_memory_unmap(dev, vq->used, virtio_queue_get_used_size(vdev, idx), 1236 0, 0); 1237 fail_alloc_used: 1238 vhost_memory_unmap(dev, vq->avail, virtio_queue_get_avail_size(vdev, idx), 1239 0, 0); 1240 fail_alloc_avail: 1241 vhost_memory_unmap(dev, vq->desc, virtio_queue_get_desc_size(vdev, idx), 1242 0, 0); 1243 fail_alloc_desc: 1244 return r; 1245 } 1246 1247 void vhost_virtqueue_stop(struct vhost_dev *dev, 1248 struct VirtIODevice *vdev, 1249 struct vhost_virtqueue *vq, 1250 unsigned idx) 1251 { 1252 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, idx); 1253 struct vhost_vring_state state = { 1254 .index = vhost_vq_index, 1255 }; 1256 int r; 1257 1258 if (virtio_queue_get_desc_addr(vdev, idx) == 0) { 1259 /* Don't stop the virtqueue which might have not been started */ 1260 return; 1261 } 1262 1263 r = dev->vhost_ops->vhost_get_vring_base(dev, &state); 1264 if (r < 0) { 1265 VHOST_OPS_DEBUG(r, "vhost VQ %u ring restore failed: %d", idx, r); 1266 /* Connection to the backend is broken, so let's sync internal 1267 * last avail idx to the device used idx. 1268 */ 1269 virtio_queue_restore_last_avail_idx(vdev, idx); 1270 } else { 1271 virtio_queue_set_last_avail_idx(vdev, idx, state.num); 1272 } 1273 virtio_queue_invalidate_signalled_used(vdev, idx); 1274 virtio_queue_update_used_idx(vdev, idx); 1275 1276 /* In the cross-endian case, we need to reset the vring endianness to 1277 * native as legacy devices expect so by default. 1278 */ 1279 if (vhost_needs_vring_endian(vdev)) { 1280 vhost_virtqueue_set_vring_endian_legacy(dev, 1281 !virtio_is_big_endian(vdev), 1282 vhost_vq_index); 1283 } 1284 1285 vhost_memory_unmap(dev, vq->used, virtio_queue_get_used_size(vdev, idx), 1286 1, virtio_queue_get_used_size(vdev, idx)); 1287 vhost_memory_unmap(dev, vq->avail, virtio_queue_get_avail_size(vdev, idx), 1288 0, virtio_queue_get_avail_size(vdev, idx)); 1289 vhost_memory_unmap(dev, vq->desc, virtio_queue_get_desc_size(vdev, idx), 1290 0, virtio_queue_get_desc_size(vdev, idx)); 1291 } 1292 1293 static int vhost_virtqueue_set_busyloop_timeout(struct vhost_dev *dev, 1294 int n, uint32_t timeout) 1295 { 1296 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, n); 1297 struct vhost_vring_state state = { 1298 .index = vhost_vq_index, 1299 .num = timeout, 1300 }; 1301 int r; 1302 1303 if (!dev->vhost_ops->vhost_set_vring_busyloop_timeout) { 1304 return -EINVAL; 1305 } 1306 1307 r = dev->vhost_ops->vhost_set_vring_busyloop_timeout(dev, &state); 1308 if (r) { 1309 VHOST_OPS_DEBUG(r, "vhost_set_vring_busyloop_timeout failed"); 1310 return r; 1311 } 1312 1313 return 0; 1314 } 1315 1316 static void vhost_virtqueue_error_notifier(EventNotifier *n) 1317 { 1318 struct vhost_virtqueue *vq = container_of(n, struct vhost_virtqueue, 1319 error_notifier); 1320 struct vhost_dev *dev = vq->dev; 1321 int index = vq - dev->vqs; 1322 1323 if (event_notifier_test_and_clear(n) && dev->vdev) { 1324 VHOST_OPS_DEBUG(-EINVAL, "vhost vring error in virtqueue %d", 1325 dev->vq_index + index); 1326 } 1327 } 1328 1329 static int vhost_virtqueue_init(struct vhost_dev *dev, 1330 struct vhost_virtqueue *vq, int n) 1331 { 1332 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, n); 1333 struct vhost_vring_file file = { 1334 .index = vhost_vq_index, 1335 }; 1336 int r = event_notifier_init(&vq->masked_notifier, 0); 1337 if (r < 0) { 1338 return r; 1339 } 1340 1341 file.fd = event_notifier_get_wfd(&vq->masked_notifier); 1342 r = dev->vhost_ops->vhost_set_vring_call(dev, &file); 1343 if (r) { 1344 VHOST_OPS_DEBUG(r, "vhost_set_vring_call failed"); 1345 goto fail_call; 1346 } 1347 1348 vq->dev = dev; 1349 1350 if (dev->vhost_ops->vhost_set_vring_err) { 1351 r = event_notifier_init(&vq->error_notifier, 0); 1352 if (r < 0) { 1353 goto fail_call; 1354 } 1355 1356 file.fd = event_notifier_get_fd(&vq->error_notifier); 1357 r = dev->vhost_ops->vhost_set_vring_err(dev, &file); 1358 if (r) { 1359 VHOST_OPS_DEBUG(r, "vhost_set_vring_err failed"); 1360 goto fail_err; 1361 } 1362 1363 event_notifier_set_handler(&vq->error_notifier, 1364 vhost_virtqueue_error_notifier); 1365 } 1366 1367 return 0; 1368 1369 fail_err: 1370 event_notifier_cleanup(&vq->error_notifier); 1371 fail_call: 1372 event_notifier_cleanup(&vq->masked_notifier); 1373 return r; 1374 } 1375 1376 static void vhost_virtqueue_cleanup(struct vhost_virtqueue *vq) 1377 { 1378 event_notifier_cleanup(&vq->masked_notifier); 1379 if (vq->dev->vhost_ops->vhost_set_vring_err) { 1380 event_notifier_set_handler(&vq->error_notifier, NULL); 1381 event_notifier_cleanup(&vq->error_notifier); 1382 } 1383 } 1384 1385 int vhost_dev_init(struct vhost_dev *hdev, void *opaque, 1386 VhostBackendType backend_type, uint32_t busyloop_timeout, 1387 Error **errp) 1388 { 1389 uint64_t features; 1390 int i, r, n_initialized_vqs = 0; 1391 1392 hdev->vdev = NULL; 1393 hdev->migration_blocker = NULL; 1394 1395 r = vhost_set_backend_type(hdev, backend_type); 1396 assert(r >= 0); 1397 1398 r = hdev->vhost_ops->vhost_backend_init(hdev, opaque, errp); 1399 if (r < 0) { 1400 goto fail; 1401 } 1402 1403 r = hdev->vhost_ops->vhost_set_owner(hdev); 1404 if (r < 0) { 1405 error_setg_errno(errp, -r, "vhost_set_owner failed"); 1406 goto fail; 1407 } 1408 1409 r = hdev->vhost_ops->vhost_get_features(hdev, &features); 1410 if (r < 0) { 1411 error_setg_errno(errp, -r, "vhost_get_features failed"); 1412 goto fail; 1413 } 1414 1415 for (i = 0; i < hdev->nvqs; ++i, ++n_initialized_vqs) { 1416 r = vhost_virtqueue_init(hdev, hdev->vqs + i, hdev->vq_index + i); 1417 if (r < 0) { 1418 error_setg_errno(errp, -r, "Failed to initialize virtqueue %d", i); 1419 goto fail; 1420 } 1421 } 1422 1423 if (busyloop_timeout) { 1424 for (i = 0; i < hdev->nvqs; ++i) { 1425 r = vhost_virtqueue_set_busyloop_timeout(hdev, hdev->vq_index + i, 1426 busyloop_timeout); 1427 if (r < 0) { 1428 error_setg_errno(errp, -r, "Failed to set busyloop timeout"); 1429 goto fail_busyloop; 1430 } 1431 } 1432 } 1433 1434 hdev->features = features; 1435 1436 hdev->memory_listener = (MemoryListener) { 1437 .name = "vhost", 1438 .begin = vhost_begin, 1439 .commit = vhost_commit, 1440 .region_add = vhost_region_addnop, 1441 .region_nop = vhost_region_addnop, 1442 .log_start = vhost_log_start, 1443 .log_stop = vhost_log_stop, 1444 .log_sync = vhost_log_sync, 1445 .log_global_start = vhost_log_global_start, 1446 .log_global_stop = vhost_log_global_stop, 1447 .priority = MEMORY_LISTENER_PRIORITY_DEV_BACKEND 1448 }; 1449 1450 hdev->iommu_listener = (MemoryListener) { 1451 .name = "vhost-iommu", 1452 .region_add = vhost_iommu_region_add, 1453 .region_del = vhost_iommu_region_del, 1454 }; 1455 1456 if (hdev->migration_blocker == NULL) { 1457 if (!(hdev->features & (0x1ULL << VHOST_F_LOG_ALL))) { 1458 error_setg(&hdev->migration_blocker, 1459 "Migration disabled: vhost lacks VHOST_F_LOG_ALL feature."); 1460 } else if (vhost_dev_log_is_shared(hdev) && !qemu_memfd_alloc_check()) { 1461 error_setg(&hdev->migration_blocker, 1462 "Migration disabled: failed to allocate shared memory"); 1463 } 1464 } 1465 1466 if (hdev->migration_blocker != NULL) { 1467 r = migrate_add_blocker(hdev->migration_blocker, errp); 1468 if (r < 0) { 1469 error_free(hdev->migration_blocker); 1470 goto fail_busyloop; 1471 } 1472 } 1473 1474 hdev->mem = g_malloc0(offsetof(struct vhost_memory, regions)); 1475 hdev->n_mem_sections = 0; 1476 hdev->mem_sections = NULL; 1477 hdev->log = NULL; 1478 hdev->log_size = 0; 1479 hdev->log_enabled = false; 1480 hdev->started = false; 1481 memory_listener_register(&hdev->memory_listener, &address_space_memory); 1482 QLIST_INSERT_HEAD(&vhost_devices, hdev, entry); 1483 1484 if (used_memslots > hdev->vhost_ops->vhost_backend_memslots_limit(hdev)) { 1485 error_setg(errp, "vhost backend memory slots limit is less" 1486 " than current number of present memory slots"); 1487 r = -EINVAL; 1488 goto fail_busyloop; 1489 } 1490 1491 return 0; 1492 1493 fail_busyloop: 1494 if (busyloop_timeout) { 1495 while (--i >= 0) { 1496 vhost_virtqueue_set_busyloop_timeout(hdev, hdev->vq_index + i, 0); 1497 } 1498 } 1499 fail: 1500 hdev->nvqs = n_initialized_vqs; 1501 vhost_dev_cleanup(hdev); 1502 return r; 1503 } 1504 1505 void vhost_dev_cleanup(struct vhost_dev *hdev) 1506 { 1507 int i; 1508 1509 trace_vhost_dev_cleanup(hdev); 1510 1511 for (i = 0; i < hdev->nvqs; ++i) { 1512 vhost_virtqueue_cleanup(hdev->vqs + i); 1513 } 1514 if (hdev->mem) { 1515 /* those are only safe after successful init */ 1516 memory_listener_unregister(&hdev->memory_listener); 1517 QLIST_REMOVE(hdev, entry); 1518 } 1519 if (hdev->migration_blocker) { 1520 migrate_del_blocker(hdev->migration_blocker); 1521 error_free(hdev->migration_blocker); 1522 } 1523 g_free(hdev->mem); 1524 g_free(hdev->mem_sections); 1525 if (hdev->vhost_ops) { 1526 hdev->vhost_ops->vhost_backend_cleanup(hdev); 1527 } 1528 assert(!hdev->log); 1529 1530 memset(hdev, 0, sizeof(struct vhost_dev)); 1531 } 1532 1533 static void vhost_dev_disable_notifiers_nvqs(struct vhost_dev *hdev, 1534 VirtIODevice *vdev, 1535 unsigned int nvqs) 1536 { 1537 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); 1538 int i, r; 1539 1540 /* 1541 * Batch all the host notifiers in a single transaction to avoid 1542 * quadratic time complexity in address_space_update_ioeventfds(). 1543 */ 1544 memory_region_transaction_begin(); 1545 1546 for (i = 0; i < nvqs; ++i) { 1547 r = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i, 1548 false); 1549 if (r < 0) { 1550 error_report("vhost VQ %d notifier cleanup failed: %d", i, -r); 1551 } 1552 assert(r >= 0); 1553 } 1554 1555 /* 1556 * The transaction expects the ioeventfds to be open when it 1557 * commits. Do it now, before the cleanup loop. 1558 */ 1559 memory_region_transaction_commit(); 1560 1561 for (i = 0; i < nvqs; ++i) { 1562 virtio_bus_cleanup_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i); 1563 } 1564 virtio_device_release_ioeventfd(vdev); 1565 } 1566 1567 /* Stop processing guest IO notifications in qemu. 1568 * Start processing them in vhost in kernel. 1569 */ 1570 int vhost_dev_enable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev) 1571 { 1572 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); 1573 int i, r; 1574 1575 /* We will pass the notifiers to the kernel, make sure that QEMU 1576 * doesn't interfere. 1577 */ 1578 r = virtio_device_grab_ioeventfd(vdev); 1579 if (r < 0) { 1580 error_report("binding does not support host notifiers"); 1581 return r; 1582 } 1583 1584 /* 1585 * Batch all the host notifiers in a single transaction to avoid 1586 * quadratic time complexity in address_space_update_ioeventfds(). 1587 */ 1588 memory_region_transaction_begin(); 1589 1590 for (i = 0; i < hdev->nvqs; ++i) { 1591 r = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i, 1592 true); 1593 if (r < 0) { 1594 error_report("vhost VQ %d notifier binding failed: %d", i, -r); 1595 memory_region_transaction_commit(); 1596 vhost_dev_disable_notifiers_nvqs(hdev, vdev, i); 1597 return r; 1598 } 1599 } 1600 1601 memory_region_transaction_commit(); 1602 1603 return 0; 1604 } 1605 1606 /* Stop processing guest IO notifications in vhost. 1607 * Start processing them in qemu. 1608 * This might actually run the qemu handlers right away, 1609 * so virtio in qemu must be completely setup when this is called. 1610 */ 1611 void vhost_dev_disable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev) 1612 { 1613 vhost_dev_disable_notifiers_nvqs(hdev, vdev, hdev->nvqs); 1614 } 1615 1616 /* Test and clear event pending status. 1617 * Should be called after unmask to avoid losing events. 1618 */ 1619 bool vhost_virtqueue_pending(struct vhost_dev *hdev, int n) 1620 { 1621 struct vhost_virtqueue *vq = hdev->vqs + n - hdev->vq_index; 1622 assert(n >= hdev->vq_index && n < hdev->vq_index + hdev->nvqs); 1623 return event_notifier_test_and_clear(&vq->masked_notifier); 1624 } 1625 1626 /* Mask/unmask events from this vq. */ 1627 void vhost_virtqueue_mask(struct vhost_dev *hdev, VirtIODevice *vdev, int n, 1628 bool mask) 1629 { 1630 struct VirtQueue *vvq = virtio_get_queue(vdev, n); 1631 int r, index = n - hdev->vq_index; 1632 struct vhost_vring_file file; 1633 1634 /* should only be called after backend is connected */ 1635 assert(hdev->vhost_ops); 1636 1637 if (mask) { 1638 assert(vdev->use_guest_notifier_mask); 1639 file.fd = event_notifier_get_wfd(&hdev->vqs[index].masked_notifier); 1640 } else { 1641 file.fd = event_notifier_get_wfd(virtio_queue_get_guest_notifier(vvq)); 1642 } 1643 1644 file.index = hdev->vhost_ops->vhost_get_vq_index(hdev, n); 1645 r = hdev->vhost_ops->vhost_set_vring_call(hdev, &file); 1646 if (r < 0) { 1647 error_report("vhost_set_vring_call failed %d", -r); 1648 } 1649 } 1650 1651 bool vhost_config_pending(struct vhost_dev *hdev) 1652 { 1653 assert(hdev->vhost_ops); 1654 if ((hdev->started == false) || 1655 (hdev->vhost_ops->vhost_set_config_call == NULL)) { 1656 return false; 1657 } 1658 1659 EventNotifier *notifier = 1660 &hdev->vqs[VHOST_QUEUE_NUM_CONFIG_INR].masked_config_notifier; 1661 return event_notifier_test_and_clear(notifier); 1662 } 1663 1664 void vhost_config_mask(struct vhost_dev *hdev, VirtIODevice *vdev, bool mask) 1665 { 1666 int fd; 1667 int r; 1668 EventNotifier *notifier = 1669 &hdev->vqs[VHOST_QUEUE_NUM_CONFIG_INR].masked_config_notifier; 1670 EventNotifier *config_notifier = &vdev->config_notifier; 1671 assert(hdev->vhost_ops); 1672 1673 if ((hdev->started == false) || 1674 (hdev->vhost_ops->vhost_set_config_call == NULL)) { 1675 return; 1676 } 1677 if (mask) { 1678 assert(vdev->use_guest_notifier_mask); 1679 fd = event_notifier_get_fd(notifier); 1680 } else { 1681 fd = event_notifier_get_fd(config_notifier); 1682 } 1683 r = hdev->vhost_ops->vhost_set_config_call(hdev, fd); 1684 if (r < 0) { 1685 error_report("vhost_set_config_call failed %d", -r); 1686 } 1687 } 1688 1689 static void vhost_stop_config_intr(struct vhost_dev *dev) 1690 { 1691 int fd = -1; 1692 assert(dev->vhost_ops); 1693 if (dev->vhost_ops->vhost_set_config_call) { 1694 dev->vhost_ops->vhost_set_config_call(dev, fd); 1695 } 1696 } 1697 1698 static void vhost_start_config_intr(struct vhost_dev *dev) 1699 { 1700 int r; 1701 1702 assert(dev->vhost_ops); 1703 int fd = event_notifier_get_fd(&dev->vdev->config_notifier); 1704 if (dev->vhost_ops->vhost_set_config_call) { 1705 r = dev->vhost_ops->vhost_set_config_call(dev, fd); 1706 if (!r) { 1707 event_notifier_set(&dev->vdev->config_notifier); 1708 } 1709 } 1710 } 1711 1712 uint64_t vhost_get_features(struct vhost_dev *hdev, const int *feature_bits, 1713 uint64_t features) 1714 { 1715 const int *bit = feature_bits; 1716 while (*bit != VHOST_INVALID_FEATURE_BIT) { 1717 uint64_t bit_mask = (1ULL << *bit); 1718 if (!(hdev->features & bit_mask)) { 1719 features &= ~bit_mask; 1720 } 1721 bit++; 1722 } 1723 return features; 1724 } 1725 1726 void vhost_ack_features(struct vhost_dev *hdev, const int *feature_bits, 1727 uint64_t features) 1728 { 1729 const int *bit = feature_bits; 1730 while (*bit != VHOST_INVALID_FEATURE_BIT) { 1731 uint64_t bit_mask = (1ULL << *bit); 1732 if (features & bit_mask) { 1733 hdev->acked_features |= bit_mask; 1734 } 1735 bit++; 1736 } 1737 } 1738 1739 int vhost_dev_get_config(struct vhost_dev *hdev, uint8_t *config, 1740 uint32_t config_len, Error **errp) 1741 { 1742 assert(hdev->vhost_ops); 1743 1744 if (hdev->vhost_ops->vhost_get_config) { 1745 return hdev->vhost_ops->vhost_get_config(hdev, config, config_len, 1746 errp); 1747 } 1748 1749 error_setg(errp, "vhost_get_config not implemented"); 1750 return -ENOSYS; 1751 } 1752 1753 int vhost_dev_set_config(struct vhost_dev *hdev, const uint8_t *data, 1754 uint32_t offset, uint32_t size, uint32_t flags) 1755 { 1756 assert(hdev->vhost_ops); 1757 1758 if (hdev->vhost_ops->vhost_set_config) { 1759 return hdev->vhost_ops->vhost_set_config(hdev, data, offset, 1760 size, flags); 1761 } 1762 1763 return -ENOSYS; 1764 } 1765 1766 void vhost_dev_set_config_notifier(struct vhost_dev *hdev, 1767 const VhostDevConfigOps *ops) 1768 { 1769 hdev->config_ops = ops; 1770 } 1771 1772 void vhost_dev_free_inflight(struct vhost_inflight *inflight) 1773 { 1774 if (inflight && inflight->addr) { 1775 qemu_memfd_free(inflight->addr, inflight->size, inflight->fd); 1776 inflight->addr = NULL; 1777 inflight->fd = -1; 1778 } 1779 } 1780 1781 static int vhost_dev_resize_inflight(struct vhost_inflight *inflight, 1782 uint64_t new_size) 1783 { 1784 Error *err = NULL; 1785 int fd = -1; 1786 void *addr = qemu_memfd_alloc("vhost-inflight", new_size, 1787 F_SEAL_GROW | F_SEAL_SHRINK | F_SEAL_SEAL, 1788 &fd, &err); 1789 1790 if (err) { 1791 error_report_err(err); 1792 return -ENOMEM; 1793 } 1794 1795 vhost_dev_free_inflight(inflight); 1796 inflight->offset = 0; 1797 inflight->addr = addr; 1798 inflight->fd = fd; 1799 inflight->size = new_size; 1800 1801 return 0; 1802 } 1803 1804 void vhost_dev_save_inflight(struct vhost_inflight *inflight, QEMUFile *f) 1805 { 1806 if (inflight->addr) { 1807 qemu_put_be64(f, inflight->size); 1808 qemu_put_be16(f, inflight->queue_size); 1809 qemu_put_buffer(f, inflight->addr, inflight->size); 1810 } else { 1811 qemu_put_be64(f, 0); 1812 } 1813 } 1814 1815 int vhost_dev_load_inflight(struct vhost_inflight *inflight, QEMUFile *f) 1816 { 1817 uint64_t size; 1818 1819 size = qemu_get_be64(f); 1820 if (!size) { 1821 return 0; 1822 } 1823 1824 if (inflight->size != size) { 1825 int ret = vhost_dev_resize_inflight(inflight, size); 1826 if (ret < 0) { 1827 return ret; 1828 } 1829 } 1830 inflight->queue_size = qemu_get_be16(f); 1831 1832 qemu_get_buffer(f, inflight->addr, size); 1833 1834 return 0; 1835 } 1836 1837 int vhost_dev_prepare_inflight(struct vhost_dev *hdev, VirtIODevice *vdev) 1838 { 1839 int r; 1840 1841 if (hdev->vhost_ops->vhost_get_inflight_fd == NULL || 1842 hdev->vhost_ops->vhost_set_inflight_fd == NULL) { 1843 return 0; 1844 } 1845 1846 hdev->vdev = vdev; 1847 1848 r = vhost_dev_set_features(hdev, hdev->log_enabled); 1849 if (r < 0) { 1850 VHOST_OPS_DEBUG(r, "vhost_dev_prepare_inflight failed"); 1851 return r; 1852 } 1853 1854 return 0; 1855 } 1856 1857 int vhost_dev_set_inflight(struct vhost_dev *dev, 1858 struct vhost_inflight *inflight) 1859 { 1860 int r; 1861 1862 if (dev->vhost_ops->vhost_set_inflight_fd && inflight->addr) { 1863 r = dev->vhost_ops->vhost_set_inflight_fd(dev, inflight); 1864 if (r) { 1865 VHOST_OPS_DEBUG(r, "vhost_set_inflight_fd failed"); 1866 return r; 1867 } 1868 } 1869 1870 return 0; 1871 } 1872 1873 int vhost_dev_get_inflight(struct vhost_dev *dev, uint16_t queue_size, 1874 struct vhost_inflight *inflight) 1875 { 1876 int r; 1877 1878 if (dev->vhost_ops->vhost_get_inflight_fd) { 1879 r = dev->vhost_ops->vhost_get_inflight_fd(dev, queue_size, inflight); 1880 if (r) { 1881 VHOST_OPS_DEBUG(r, "vhost_get_inflight_fd failed"); 1882 return r; 1883 } 1884 } 1885 1886 return 0; 1887 } 1888 1889 static int vhost_dev_set_vring_enable(struct vhost_dev *hdev, int enable) 1890 { 1891 if (!hdev->vhost_ops->vhost_set_vring_enable) { 1892 return 0; 1893 } 1894 1895 /* 1896 * For vhost-user devices, if VHOST_USER_F_PROTOCOL_FEATURES has not 1897 * been negotiated, the rings start directly in the enabled state, and 1898 * .vhost_set_vring_enable callback will fail since 1899 * VHOST_USER_SET_VRING_ENABLE is not supported. 1900 */ 1901 if (hdev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER && 1902 !virtio_has_feature(hdev->backend_features, 1903 VHOST_USER_F_PROTOCOL_FEATURES)) { 1904 return 0; 1905 } 1906 1907 return hdev->vhost_ops->vhost_set_vring_enable(hdev, enable); 1908 } 1909 1910 /* Host notifiers must be enabled at this point. */ 1911 int vhost_dev_start(struct vhost_dev *hdev, VirtIODevice *vdev, bool vrings) 1912 { 1913 int i, r; 1914 1915 /* should only be called after backend is connected */ 1916 assert(hdev->vhost_ops); 1917 1918 trace_vhost_dev_start(hdev, vdev->name, vrings); 1919 1920 vdev->vhost_started = true; 1921 hdev->started = true; 1922 hdev->vdev = vdev; 1923 1924 r = vhost_dev_set_features(hdev, hdev->log_enabled); 1925 if (r < 0) { 1926 goto fail_features; 1927 } 1928 1929 if (vhost_dev_has_iommu(hdev)) { 1930 memory_listener_register(&hdev->iommu_listener, vdev->dma_as); 1931 } 1932 1933 r = hdev->vhost_ops->vhost_set_mem_table(hdev, hdev->mem); 1934 if (r < 0) { 1935 VHOST_OPS_DEBUG(r, "vhost_set_mem_table failed"); 1936 goto fail_mem; 1937 } 1938 for (i = 0; i < hdev->nvqs; ++i) { 1939 r = vhost_virtqueue_start(hdev, 1940 vdev, 1941 hdev->vqs + i, 1942 hdev->vq_index + i); 1943 if (r < 0) { 1944 goto fail_vq; 1945 } 1946 } 1947 1948 r = event_notifier_init( 1949 &hdev->vqs[VHOST_QUEUE_NUM_CONFIG_INR].masked_config_notifier, 0); 1950 if (r < 0) { 1951 VHOST_OPS_DEBUG(r, "event_notifier_init failed"); 1952 goto fail_vq; 1953 } 1954 event_notifier_test_and_clear( 1955 &hdev->vqs[VHOST_QUEUE_NUM_CONFIG_INR].masked_config_notifier); 1956 if (!vdev->use_guest_notifier_mask) { 1957 vhost_config_mask(hdev, vdev, true); 1958 } 1959 if (hdev->log_enabled) { 1960 uint64_t log_base; 1961 1962 hdev->log_size = vhost_get_log_size(hdev); 1963 hdev->log = vhost_log_get(hdev->log_size, 1964 vhost_dev_log_is_shared(hdev)); 1965 log_base = (uintptr_t)hdev->log->log; 1966 r = hdev->vhost_ops->vhost_set_log_base(hdev, 1967 hdev->log_size ? log_base : 0, 1968 hdev->log); 1969 if (r < 0) { 1970 VHOST_OPS_DEBUG(r, "vhost_set_log_base failed"); 1971 goto fail_log; 1972 } 1973 } 1974 if (vrings) { 1975 r = vhost_dev_set_vring_enable(hdev, true); 1976 if (r) { 1977 goto fail_log; 1978 } 1979 } 1980 if (hdev->vhost_ops->vhost_dev_start) { 1981 r = hdev->vhost_ops->vhost_dev_start(hdev, true); 1982 if (r) { 1983 goto fail_start; 1984 } 1985 } 1986 if (vhost_dev_has_iommu(hdev) && 1987 hdev->vhost_ops->vhost_set_iotlb_callback) { 1988 hdev->vhost_ops->vhost_set_iotlb_callback(hdev, true); 1989 1990 /* Update used ring information for IOTLB to work correctly, 1991 * vhost-kernel code requires for this.*/ 1992 for (i = 0; i < hdev->nvqs; ++i) { 1993 struct vhost_virtqueue *vq = hdev->vqs + i; 1994 vhost_device_iotlb_miss(hdev, vq->used_phys, true); 1995 } 1996 } 1997 vhost_start_config_intr(hdev); 1998 return 0; 1999 fail_start: 2000 if (vrings) { 2001 vhost_dev_set_vring_enable(hdev, false); 2002 } 2003 fail_log: 2004 vhost_log_put(hdev, false); 2005 fail_vq: 2006 while (--i >= 0) { 2007 vhost_virtqueue_stop(hdev, 2008 vdev, 2009 hdev->vqs + i, 2010 hdev->vq_index + i); 2011 } 2012 2013 fail_mem: 2014 if (vhost_dev_has_iommu(hdev)) { 2015 memory_listener_unregister(&hdev->iommu_listener); 2016 } 2017 fail_features: 2018 vdev->vhost_started = false; 2019 hdev->started = false; 2020 return r; 2021 } 2022 2023 /* Host notifiers must be enabled at this point. */ 2024 void vhost_dev_stop(struct vhost_dev *hdev, VirtIODevice *vdev, bool vrings) 2025 { 2026 int i; 2027 2028 /* should only be called after backend is connected */ 2029 assert(hdev->vhost_ops); 2030 event_notifier_test_and_clear( 2031 &hdev->vqs[VHOST_QUEUE_NUM_CONFIG_INR].masked_config_notifier); 2032 event_notifier_test_and_clear(&vdev->config_notifier); 2033 2034 trace_vhost_dev_stop(hdev, vdev->name, vrings); 2035 2036 if (hdev->vhost_ops->vhost_dev_start) { 2037 hdev->vhost_ops->vhost_dev_start(hdev, false); 2038 } 2039 if (vrings) { 2040 vhost_dev_set_vring_enable(hdev, false); 2041 } 2042 for (i = 0; i < hdev->nvqs; ++i) { 2043 vhost_virtqueue_stop(hdev, 2044 vdev, 2045 hdev->vqs + i, 2046 hdev->vq_index + i); 2047 } 2048 if (hdev->vhost_ops->vhost_reset_status) { 2049 hdev->vhost_ops->vhost_reset_status(hdev); 2050 } 2051 2052 if (vhost_dev_has_iommu(hdev)) { 2053 if (hdev->vhost_ops->vhost_set_iotlb_callback) { 2054 hdev->vhost_ops->vhost_set_iotlb_callback(hdev, false); 2055 } 2056 memory_listener_unregister(&hdev->iommu_listener); 2057 } 2058 vhost_stop_config_intr(hdev); 2059 vhost_log_put(hdev, true); 2060 hdev->started = false; 2061 vdev->vhost_started = false; 2062 hdev->vdev = NULL; 2063 } 2064 2065 int vhost_net_set_backend(struct vhost_dev *hdev, 2066 struct vhost_vring_file *file) 2067 { 2068 if (hdev->vhost_ops->vhost_net_set_backend) { 2069 return hdev->vhost_ops->vhost_net_set_backend(hdev, file); 2070 } 2071 2072 return -ENOSYS; 2073 } 2074