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 "hw/virtio/virtio-bus.h" 25 #include "hw/virtio/virtio-access.h" 26 #include "migration/blocker.h" 27 #include "migration/qemu-file-types.h" 28 #include "sysemu/dma.h" 29 #include "sysemu/tcg.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 = qatomic_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 return log_size; 175 } 176 177 static int vhost_set_backend_type(struct vhost_dev *dev, 178 VhostBackendType backend_type) 179 { 180 int r = 0; 181 182 switch (backend_type) { 183 #ifdef CONFIG_VHOST_KERNEL 184 case VHOST_BACKEND_TYPE_KERNEL: 185 dev->vhost_ops = &kernel_ops; 186 break; 187 #endif 188 #ifdef CONFIG_VHOST_USER 189 case VHOST_BACKEND_TYPE_USER: 190 dev->vhost_ops = &user_ops; 191 break; 192 #endif 193 #ifdef CONFIG_VHOST_VDPA 194 case VHOST_BACKEND_TYPE_VDPA: 195 dev->vhost_ops = &vdpa_ops; 196 break; 197 #endif 198 default: 199 error_report("Unknown vhost backend type"); 200 r = -1; 201 } 202 203 return r; 204 } 205 206 static struct vhost_log *vhost_log_alloc(uint64_t size, bool share) 207 { 208 Error *err = NULL; 209 struct vhost_log *log; 210 uint64_t logsize = size * sizeof(*(log->log)); 211 int fd = -1; 212 213 log = g_new0(struct vhost_log, 1); 214 if (share) { 215 log->log = qemu_memfd_alloc("vhost-log", logsize, 216 F_SEAL_GROW | F_SEAL_SHRINK | F_SEAL_SEAL, 217 &fd, &err); 218 if (err) { 219 error_report_err(err); 220 g_free(log); 221 return NULL; 222 } 223 memset(log->log, 0, logsize); 224 } else { 225 log->log = g_malloc0(logsize); 226 } 227 228 log->size = size; 229 log->refcnt = 1; 230 log->fd = fd; 231 232 return log; 233 } 234 235 static struct vhost_log *vhost_log_get(uint64_t size, bool share) 236 { 237 struct vhost_log *log = share ? vhost_log_shm : vhost_log; 238 239 if (!log || log->size != size) { 240 log = vhost_log_alloc(size, share); 241 if (share) { 242 vhost_log_shm = log; 243 } else { 244 vhost_log = log; 245 } 246 } else { 247 ++log->refcnt; 248 } 249 250 return log; 251 } 252 253 static void vhost_log_put(struct vhost_dev *dev, bool sync) 254 { 255 struct vhost_log *log = dev->log; 256 257 if (!log) { 258 return; 259 } 260 261 --log->refcnt; 262 if (log->refcnt == 0) { 263 /* Sync only the range covered by the old log */ 264 if (dev->log_size && sync) { 265 vhost_log_sync_range(dev, 0, dev->log_size * VHOST_LOG_CHUNK - 1); 266 } 267 268 if (vhost_log == log) { 269 g_free(log->log); 270 vhost_log = NULL; 271 } else if (vhost_log_shm == log) { 272 qemu_memfd_free(log->log, log->size * sizeof(*(log->log)), 273 log->fd); 274 vhost_log_shm = NULL; 275 } 276 277 g_free(log); 278 } 279 280 dev->log = NULL; 281 dev->log_size = 0; 282 } 283 284 static bool vhost_dev_log_is_shared(struct vhost_dev *dev) 285 { 286 return dev->vhost_ops->vhost_requires_shm_log && 287 dev->vhost_ops->vhost_requires_shm_log(dev); 288 } 289 290 static inline void vhost_dev_log_resize(struct vhost_dev *dev, uint64_t size) 291 { 292 struct vhost_log *log = vhost_log_get(size, vhost_dev_log_is_shared(dev)); 293 uint64_t log_base = (uintptr_t)log->log; 294 int r; 295 296 /* inform backend of log switching, this must be done before 297 releasing the current log, to ensure no logging is lost */ 298 r = dev->vhost_ops->vhost_set_log_base(dev, log_base, log); 299 if (r < 0) { 300 VHOST_OPS_DEBUG("vhost_set_log_base failed"); 301 } 302 303 vhost_log_put(dev, true); 304 dev->log = log; 305 dev->log_size = size; 306 } 307 308 static int vhost_dev_has_iommu(struct vhost_dev *dev) 309 { 310 VirtIODevice *vdev = dev->vdev; 311 312 /* 313 * For vhost, VIRTIO_F_IOMMU_PLATFORM means the backend support 314 * incremental memory mapping API via IOTLB API. For platform that 315 * does not have IOMMU, there's no need to enable this feature 316 * which may cause unnecessary IOTLB miss/update trnasactions. 317 */ 318 return virtio_bus_device_iommu_enabled(vdev) && 319 virtio_host_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM); 320 } 321 322 static void *vhost_memory_map(struct vhost_dev *dev, hwaddr addr, 323 hwaddr *plen, bool is_write) 324 { 325 if (!vhost_dev_has_iommu(dev)) { 326 return cpu_physical_memory_map(addr, plen, is_write); 327 } else { 328 return (void *)(uintptr_t)addr; 329 } 330 } 331 332 static void vhost_memory_unmap(struct vhost_dev *dev, void *buffer, 333 hwaddr len, int is_write, 334 hwaddr access_len) 335 { 336 if (!vhost_dev_has_iommu(dev)) { 337 cpu_physical_memory_unmap(buffer, len, is_write, access_len); 338 } 339 } 340 341 static int vhost_verify_ring_part_mapping(void *ring_hva, 342 uint64_t ring_gpa, 343 uint64_t ring_size, 344 void *reg_hva, 345 uint64_t reg_gpa, 346 uint64_t reg_size) 347 { 348 uint64_t hva_ring_offset; 349 uint64_t ring_last = range_get_last(ring_gpa, ring_size); 350 uint64_t reg_last = range_get_last(reg_gpa, reg_size); 351 352 if (ring_last < reg_gpa || ring_gpa > reg_last) { 353 return 0; 354 } 355 /* check that whole ring's is mapped */ 356 if (ring_last > reg_last) { 357 return -ENOMEM; 358 } 359 /* check that ring's MemoryRegion wasn't replaced */ 360 hva_ring_offset = ring_gpa - reg_gpa; 361 if (ring_hva != reg_hva + hva_ring_offset) { 362 return -EBUSY; 363 } 364 365 return 0; 366 } 367 368 static int vhost_verify_ring_mappings(struct vhost_dev *dev, 369 void *reg_hva, 370 uint64_t reg_gpa, 371 uint64_t reg_size) 372 { 373 int i, j; 374 int r = 0; 375 const char *part_name[] = { 376 "descriptor table", 377 "available ring", 378 "used ring" 379 }; 380 381 if (vhost_dev_has_iommu(dev)) { 382 return 0; 383 } 384 385 for (i = 0; i < dev->nvqs; ++i) { 386 struct vhost_virtqueue *vq = dev->vqs + i; 387 388 if (vq->desc_phys == 0) { 389 continue; 390 } 391 392 j = 0; 393 r = vhost_verify_ring_part_mapping( 394 vq->desc, vq->desc_phys, vq->desc_size, 395 reg_hva, reg_gpa, reg_size); 396 if (r) { 397 break; 398 } 399 400 j++; 401 r = vhost_verify_ring_part_mapping( 402 vq->avail, vq->avail_phys, vq->avail_size, 403 reg_hva, reg_gpa, reg_size); 404 if (r) { 405 break; 406 } 407 408 j++; 409 r = vhost_verify_ring_part_mapping( 410 vq->used, vq->used_phys, vq->used_size, 411 reg_hva, reg_gpa, reg_size); 412 if (r) { 413 break; 414 } 415 } 416 417 if (r == -ENOMEM) { 418 error_report("Unable to map %s for ring %d", part_name[j], i); 419 } else if (r == -EBUSY) { 420 error_report("%s relocated for ring %d", part_name[j], i); 421 } 422 return r; 423 } 424 425 /* 426 * vhost_section: identify sections needed for vhost access 427 * 428 * We only care about RAM sections here (where virtqueue and guest 429 * internals accessed by virtio might live). If we find one we still 430 * allow the backend to potentially filter it out of our list. 431 */ 432 static bool vhost_section(struct vhost_dev *dev, MemoryRegionSection *section) 433 { 434 MemoryRegion *mr = section->mr; 435 436 if (memory_region_is_ram(mr) && !memory_region_is_rom(mr)) { 437 uint8_t dirty_mask = memory_region_get_dirty_log_mask(mr); 438 uint8_t handled_dirty; 439 440 /* 441 * Kernel based vhost doesn't handle any block which is doing 442 * dirty-tracking other than migration for which it has 443 * specific logging support. However for TCG the kernel never 444 * gets involved anyway so we can also ignore it's 445 * self-modiying code detection flags. However a vhost-user 446 * client could still confuse a TCG guest if it re-writes 447 * executable memory that has already been translated. 448 */ 449 handled_dirty = (1 << DIRTY_MEMORY_MIGRATION) | 450 (1 << DIRTY_MEMORY_CODE); 451 452 if (dirty_mask & ~handled_dirty) { 453 trace_vhost_reject_section(mr->name, 1); 454 return false; 455 } 456 457 if (dev->vhost_ops->vhost_backend_mem_section_filter && 458 !dev->vhost_ops->vhost_backend_mem_section_filter(dev, section)) { 459 trace_vhost_reject_section(mr->name, 2); 460 return false; 461 } 462 463 trace_vhost_section(mr->name); 464 return true; 465 } else { 466 trace_vhost_reject_section(mr->name, 3); 467 return false; 468 } 469 } 470 471 static void vhost_begin(MemoryListener *listener) 472 { 473 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 474 memory_listener); 475 dev->tmp_sections = NULL; 476 dev->n_tmp_sections = 0; 477 } 478 479 static void vhost_commit(MemoryListener *listener) 480 { 481 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 482 memory_listener); 483 MemoryRegionSection *old_sections; 484 int n_old_sections; 485 uint64_t log_size; 486 size_t regions_size; 487 int r; 488 int i; 489 bool changed = false; 490 491 /* Note we can be called before the device is started, but then 492 * starting the device calls set_mem_table, so we need to have 493 * built the data structures. 494 */ 495 old_sections = dev->mem_sections; 496 n_old_sections = dev->n_mem_sections; 497 dev->mem_sections = dev->tmp_sections; 498 dev->n_mem_sections = dev->n_tmp_sections; 499 500 if (dev->n_mem_sections != n_old_sections) { 501 changed = true; 502 } else { 503 /* Same size, lets check the contents */ 504 for (int i = 0; i < n_old_sections; i++) { 505 if (!MemoryRegionSection_eq(&old_sections[i], 506 &dev->mem_sections[i])) { 507 changed = true; 508 break; 509 } 510 } 511 } 512 513 trace_vhost_commit(dev->started, changed); 514 if (!changed) { 515 goto out; 516 } 517 518 /* Rebuild the regions list from the new sections list */ 519 regions_size = offsetof(struct vhost_memory, regions) + 520 dev->n_mem_sections * sizeof dev->mem->regions[0]; 521 dev->mem = g_realloc(dev->mem, regions_size); 522 dev->mem->nregions = dev->n_mem_sections; 523 used_memslots = dev->mem->nregions; 524 for (i = 0; i < dev->n_mem_sections; i++) { 525 struct vhost_memory_region *cur_vmr = dev->mem->regions + i; 526 struct MemoryRegionSection *mrs = dev->mem_sections + i; 527 528 cur_vmr->guest_phys_addr = mrs->offset_within_address_space; 529 cur_vmr->memory_size = int128_get64(mrs->size); 530 cur_vmr->userspace_addr = 531 (uintptr_t)memory_region_get_ram_ptr(mrs->mr) + 532 mrs->offset_within_region; 533 cur_vmr->flags_padding = 0; 534 } 535 536 if (!dev->started) { 537 goto out; 538 } 539 540 for (i = 0; i < dev->mem->nregions; i++) { 541 if (vhost_verify_ring_mappings(dev, 542 (void *)(uintptr_t)dev->mem->regions[i].userspace_addr, 543 dev->mem->regions[i].guest_phys_addr, 544 dev->mem->regions[i].memory_size)) { 545 error_report("Verify ring failure on region %d", i); 546 abort(); 547 } 548 } 549 550 if (!dev->log_enabled) { 551 r = dev->vhost_ops->vhost_set_mem_table(dev, dev->mem); 552 if (r < 0) { 553 VHOST_OPS_DEBUG("vhost_set_mem_table failed"); 554 } 555 goto out; 556 } 557 log_size = vhost_get_log_size(dev); 558 /* We allocate an extra 4K bytes to log, 559 * to reduce the * number of reallocations. */ 560 #define VHOST_LOG_BUFFER (0x1000 / sizeof *dev->log) 561 /* To log more, must increase log size before table update. */ 562 if (dev->log_size < log_size) { 563 vhost_dev_log_resize(dev, log_size + VHOST_LOG_BUFFER); 564 } 565 r = dev->vhost_ops->vhost_set_mem_table(dev, dev->mem); 566 if (r < 0) { 567 VHOST_OPS_DEBUG("vhost_set_mem_table failed"); 568 } 569 /* To log less, can only decrease log size after table update. */ 570 if (dev->log_size > log_size + VHOST_LOG_BUFFER) { 571 vhost_dev_log_resize(dev, log_size); 572 } 573 574 out: 575 /* Deref the old list of sections, this must happen _after_ the 576 * vhost_set_mem_table to ensure the client isn't still using the 577 * section we're about to unref. 578 */ 579 while (n_old_sections--) { 580 memory_region_unref(old_sections[n_old_sections].mr); 581 } 582 g_free(old_sections); 583 return; 584 } 585 586 /* Adds the section data to the tmp_section structure. 587 * It relies on the listener calling us in memory address order 588 * and for each region (via the _add and _nop methods) to 589 * join neighbours. 590 */ 591 static void vhost_region_add_section(struct vhost_dev *dev, 592 MemoryRegionSection *section) 593 { 594 bool need_add = true; 595 uint64_t mrs_size = int128_get64(section->size); 596 uint64_t mrs_gpa = section->offset_within_address_space; 597 uintptr_t mrs_host = (uintptr_t)memory_region_get_ram_ptr(section->mr) + 598 section->offset_within_region; 599 RAMBlock *mrs_rb = section->mr->ram_block; 600 601 trace_vhost_region_add_section(section->mr->name, mrs_gpa, mrs_size, 602 mrs_host); 603 604 if (dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER) { 605 /* Round the section to it's page size */ 606 /* First align the start down to a page boundary */ 607 size_t mrs_page = qemu_ram_pagesize(mrs_rb); 608 uint64_t alignage = mrs_host & (mrs_page - 1); 609 if (alignage) { 610 mrs_host -= alignage; 611 mrs_size += alignage; 612 mrs_gpa -= alignage; 613 } 614 /* Now align the size up to a page boundary */ 615 alignage = mrs_size & (mrs_page - 1); 616 if (alignage) { 617 mrs_size += mrs_page - alignage; 618 } 619 trace_vhost_region_add_section_aligned(section->mr->name, mrs_gpa, 620 mrs_size, mrs_host); 621 } 622 623 if (dev->n_tmp_sections) { 624 /* Since we already have at least one section, lets see if 625 * this extends it; since we're scanning in order, we only 626 * have to look at the last one, and the FlatView that calls 627 * us shouldn't have overlaps. 628 */ 629 MemoryRegionSection *prev_sec = dev->tmp_sections + 630 (dev->n_tmp_sections - 1); 631 uint64_t prev_gpa_start = prev_sec->offset_within_address_space; 632 uint64_t prev_size = int128_get64(prev_sec->size); 633 uint64_t prev_gpa_end = range_get_last(prev_gpa_start, prev_size); 634 uint64_t prev_host_start = 635 (uintptr_t)memory_region_get_ram_ptr(prev_sec->mr) + 636 prev_sec->offset_within_region; 637 uint64_t prev_host_end = range_get_last(prev_host_start, prev_size); 638 639 if (mrs_gpa <= (prev_gpa_end + 1)) { 640 /* OK, looks like overlapping/intersecting - it's possible that 641 * the rounding to page sizes has made them overlap, but they should 642 * match up in the same RAMBlock if they do. 643 */ 644 if (mrs_gpa < prev_gpa_start) { 645 error_report("%s:Section '%s' rounded to %"PRIx64 646 " prior to previous '%s' %"PRIx64, 647 __func__, section->mr->name, mrs_gpa, 648 prev_sec->mr->name, prev_gpa_start); 649 /* A way to cleanly fail here would be better */ 650 return; 651 } 652 /* Offset from the start of the previous GPA to this GPA */ 653 size_t offset = mrs_gpa - prev_gpa_start; 654 655 if (prev_host_start + offset == mrs_host && 656 section->mr == prev_sec->mr && 657 (!dev->vhost_ops->vhost_backend_can_merge || 658 dev->vhost_ops->vhost_backend_can_merge(dev, 659 mrs_host, mrs_size, 660 prev_host_start, prev_size))) { 661 uint64_t max_end = MAX(prev_host_end, mrs_host + mrs_size); 662 need_add = false; 663 prev_sec->offset_within_address_space = 664 MIN(prev_gpa_start, mrs_gpa); 665 prev_sec->offset_within_region = 666 MIN(prev_host_start, mrs_host) - 667 (uintptr_t)memory_region_get_ram_ptr(prev_sec->mr); 668 prev_sec->size = int128_make64(max_end - MIN(prev_host_start, 669 mrs_host)); 670 trace_vhost_region_add_section_merge(section->mr->name, 671 int128_get64(prev_sec->size), 672 prev_sec->offset_within_address_space, 673 prev_sec->offset_within_region); 674 } else { 675 /* adjoining regions are fine, but overlapping ones with 676 * different blocks/offsets shouldn't happen 677 */ 678 if (mrs_gpa != prev_gpa_end + 1) { 679 error_report("%s: Overlapping but not coherent sections " 680 "at %"PRIx64, 681 __func__, mrs_gpa); 682 return; 683 } 684 } 685 } 686 } 687 688 if (need_add) { 689 ++dev->n_tmp_sections; 690 dev->tmp_sections = g_renew(MemoryRegionSection, dev->tmp_sections, 691 dev->n_tmp_sections); 692 dev->tmp_sections[dev->n_tmp_sections - 1] = *section; 693 /* The flatview isn't stable and we don't use it, making it NULL 694 * means we can memcmp the list. 695 */ 696 dev->tmp_sections[dev->n_tmp_sections - 1].fv = NULL; 697 memory_region_ref(section->mr); 698 } 699 } 700 701 /* Used for both add and nop callbacks */ 702 static void vhost_region_addnop(MemoryListener *listener, 703 MemoryRegionSection *section) 704 { 705 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 706 memory_listener); 707 708 if (!vhost_section(dev, section)) { 709 return; 710 } 711 vhost_region_add_section(dev, section); 712 } 713 714 static void vhost_iommu_unmap_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb) 715 { 716 struct vhost_iommu *iommu = container_of(n, struct vhost_iommu, n); 717 struct vhost_dev *hdev = iommu->hdev; 718 hwaddr iova = iotlb->iova + iommu->iommu_offset; 719 720 if (vhost_backend_invalidate_device_iotlb(hdev, iova, 721 iotlb->addr_mask + 1)) { 722 error_report("Fail to invalidate device iotlb"); 723 } 724 } 725 726 static void vhost_iommu_region_add(MemoryListener *listener, 727 MemoryRegionSection *section) 728 { 729 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 730 iommu_listener); 731 struct vhost_iommu *iommu; 732 Int128 end; 733 int iommu_idx; 734 IOMMUMemoryRegion *iommu_mr; 735 int ret; 736 737 if (!memory_region_is_iommu(section->mr)) { 738 return; 739 } 740 741 iommu_mr = IOMMU_MEMORY_REGION(section->mr); 742 743 iommu = g_malloc0(sizeof(*iommu)); 744 end = int128_add(int128_make64(section->offset_within_region), 745 section->size); 746 end = int128_sub(end, int128_one()); 747 iommu_idx = memory_region_iommu_attrs_to_index(iommu_mr, 748 MEMTXATTRS_UNSPECIFIED); 749 iommu_notifier_init(&iommu->n, vhost_iommu_unmap_notify, 750 IOMMU_NOTIFIER_DEVIOTLB_UNMAP, 751 section->offset_within_region, 752 int128_get64(end), 753 iommu_idx); 754 iommu->mr = section->mr; 755 iommu->iommu_offset = section->offset_within_address_space - 756 section->offset_within_region; 757 iommu->hdev = dev; 758 ret = memory_region_register_iommu_notifier(section->mr, &iommu->n, NULL); 759 if (ret) { 760 /* 761 * Some vIOMMUs do not support dev-iotlb yet. If so, try to use the 762 * UNMAP legacy message 763 */ 764 iommu->n.notifier_flags = IOMMU_NOTIFIER_UNMAP; 765 memory_region_register_iommu_notifier(section->mr, &iommu->n, 766 &error_fatal); 767 } 768 QLIST_INSERT_HEAD(&dev->iommu_list, iommu, iommu_next); 769 /* TODO: can replay help performance here? */ 770 } 771 772 static void vhost_iommu_region_del(MemoryListener *listener, 773 MemoryRegionSection *section) 774 { 775 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 776 iommu_listener); 777 struct vhost_iommu *iommu; 778 779 if (!memory_region_is_iommu(section->mr)) { 780 return; 781 } 782 783 QLIST_FOREACH(iommu, &dev->iommu_list, iommu_next) { 784 if (iommu->mr == section->mr && 785 iommu->n.start == section->offset_within_region) { 786 memory_region_unregister_iommu_notifier(iommu->mr, 787 &iommu->n); 788 QLIST_REMOVE(iommu, iommu_next); 789 g_free(iommu); 790 break; 791 } 792 } 793 } 794 795 static int vhost_virtqueue_set_addr(struct vhost_dev *dev, 796 struct vhost_virtqueue *vq, 797 unsigned idx, bool enable_log) 798 { 799 struct vhost_vring_addr addr; 800 int r; 801 memset(&addr, 0, sizeof(struct vhost_vring_addr)); 802 803 if (dev->vhost_ops->vhost_vq_get_addr) { 804 r = dev->vhost_ops->vhost_vq_get_addr(dev, &addr, vq); 805 if (r < 0) { 806 VHOST_OPS_DEBUG("vhost_vq_get_addr failed"); 807 return -errno; 808 } 809 } else { 810 addr.desc_user_addr = (uint64_t)(unsigned long)vq->desc; 811 addr.avail_user_addr = (uint64_t)(unsigned long)vq->avail; 812 addr.used_user_addr = (uint64_t)(unsigned long)vq->used; 813 } 814 addr.index = idx; 815 addr.log_guest_addr = vq->used_phys; 816 addr.flags = enable_log ? (1 << VHOST_VRING_F_LOG) : 0; 817 r = dev->vhost_ops->vhost_set_vring_addr(dev, &addr); 818 if (r < 0) { 819 VHOST_OPS_DEBUG("vhost_set_vring_addr failed"); 820 return -errno; 821 } 822 return 0; 823 } 824 825 static int vhost_dev_set_features(struct vhost_dev *dev, 826 bool enable_log) 827 { 828 uint64_t features = dev->acked_features; 829 int r; 830 if (enable_log) { 831 features |= 0x1ULL << VHOST_F_LOG_ALL; 832 } 833 if (!vhost_dev_has_iommu(dev)) { 834 features &= ~(0x1ULL << VIRTIO_F_IOMMU_PLATFORM); 835 } 836 if (dev->vhost_ops->vhost_force_iommu) { 837 if (dev->vhost_ops->vhost_force_iommu(dev) == true) { 838 features |= 0x1ULL << VIRTIO_F_IOMMU_PLATFORM; 839 } 840 } 841 r = dev->vhost_ops->vhost_set_features(dev, features); 842 if (r < 0) { 843 VHOST_OPS_DEBUG("vhost_set_features failed"); 844 goto out; 845 } 846 if (dev->vhost_ops->vhost_set_backend_cap) { 847 r = dev->vhost_ops->vhost_set_backend_cap(dev); 848 if (r < 0) { 849 VHOST_OPS_DEBUG("vhost_set_backend_cap failed"); 850 goto out; 851 } 852 } 853 854 out: 855 return r < 0 ? -errno : 0; 856 } 857 858 static int vhost_dev_set_log(struct vhost_dev *dev, bool enable_log) 859 { 860 int r, i, idx; 861 hwaddr addr; 862 863 r = vhost_dev_set_features(dev, enable_log); 864 if (r < 0) { 865 goto err_features; 866 } 867 for (i = 0; i < dev->nvqs; ++i) { 868 idx = dev->vhost_ops->vhost_get_vq_index(dev, dev->vq_index + i); 869 addr = virtio_queue_get_desc_addr(dev->vdev, idx); 870 if (!addr) { 871 /* 872 * The queue might not be ready for start. If this 873 * is the case there is no reason to continue the process. 874 * The similar logic is used by the vhost_virtqueue_start() 875 * routine. 876 */ 877 continue; 878 } 879 r = vhost_virtqueue_set_addr(dev, dev->vqs + i, idx, 880 enable_log); 881 if (r < 0) { 882 goto err_vq; 883 } 884 } 885 return 0; 886 err_vq: 887 for (; i >= 0; --i) { 888 idx = dev->vhost_ops->vhost_get_vq_index(dev, dev->vq_index + i); 889 vhost_virtqueue_set_addr(dev, dev->vqs + i, idx, 890 dev->log_enabled); 891 } 892 vhost_dev_set_features(dev, dev->log_enabled); 893 err_features: 894 return r; 895 } 896 897 static int vhost_migration_log(MemoryListener *listener, bool enable) 898 { 899 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 900 memory_listener); 901 int r; 902 if (enable == dev->log_enabled) { 903 return 0; 904 } 905 if (!dev->started) { 906 dev->log_enabled = enable; 907 return 0; 908 } 909 910 r = 0; 911 if (!enable) { 912 r = vhost_dev_set_log(dev, false); 913 if (r < 0) { 914 goto check_dev_state; 915 } 916 vhost_log_put(dev, false); 917 } else { 918 vhost_dev_log_resize(dev, vhost_get_log_size(dev)); 919 r = vhost_dev_set_log(dev, true); 920 if (r < 0) { 921 goto check_dev_state; 922 } 923 } 924 925 check_dev_state: 926 dev->log_enabled = enable; 927 /* 928 * vhost-user-* devices could change their state during log 929 * initialization due to disconnect. So check dev state after 930 * vhost communication. 931 */ 932 if (!dev->started) { 933 /* 934 * Since device is in the stopped state, it is okay for 935 * migration. Return success. 936 */ 937 r = 0; 938 } 939 if (r) { 940 /* An error occurred. */ 941 dev->log_enabled = false; 942 } 943 944 return r; 945 } 946 947 static void vhost_log_global_start(MemoryListener *listener) 948 { 949 int r; 950 951 r = vhost_migration_log(listener, true); 952 if (r < 0) { 953 abort(); 954 } 955 } 956 957 static void vhost_log_global_stop(MemoryListener *listener) 958 { 959 int r; 960 961 r = vhost_migration_log(listener, false); 962 if (r < 0) { 963 abort(); 964 } 965 } 966 967 static void vhost_log_start(MemoryListener *listener, 968 MemoryRegionSection *section, 969 int old, int new) 970 { 971 /* FIXME: implement */ 972 } 973 974 static void vhost_log_stop(MemoryListener *listener, 975 MemoryRegionSection *section, 976 int old, int new) 977 { 978 /* FIXME: implement */ 979 } 980 981 /* The vhost driver natively knows how to handle the vrings of non 982 * cross-endian legacy devices and modern devices. Only legacy devices 983 * exposed to a bi-endian guest may require the vhost driver to use a 984 * specific endianness. 985 */ 986 static inline bool vhost_needs_vring_endian(VirtIODevice *vdev) 987 { 988 if (virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) { 989 return false; 990 } 991 #ifdef HOST_WORDS_BIGENDIAN 992 return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_LITTLE; 993 #else 994 return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG; 995 #endif 996 } 997 998 static int vhost_virtqueue_set_vring_endian_legacy(struct vhost_dev *dev, 999 bool is_big_endian, 1000 int vhost_vq_index) 1001 { 1002 struct vhost_vring_state s = { 1003 .index = vhost_vq_index, 1004 .num = is_big_endian 1005 }; 1006 1007 if (!dev->vhost_ops->vhost_set_vring_endian(dev, &s)) { 1008 return 0; 1009 } 1010 1011 VHOST_OPS_DEBUG("vhost_set_vring_endian failed"); 1012 if (errno == ENOTTY) { 1013 error_report("vhost does not support cross-endian"); 1014 return -ENOSYS; 1015 } 1016 1017 return -errno; 1018 } 1019 1020 static int vhost_memory_region_lookup(struct vhost_dev *hdev, 1021 uint64_t gpa, uint64_t *uaddr, 1022 uint64_t *len) 1023 { 1024 int i; 1025 1026 for (i = 0; i < hdev->mem->nregions; i++) { 1027 struct vhost_memory_region *reg = hdev->mem->regions + i; 1028 1029 if (gpa >= reg->guest_phys_addr && 1030 reg->guest_phys_addr + reg->memory_size > gpa) { 1031 *uaddr = reg->userspace_addr + gpa - reg->guest_phys_addr; 1032 *len = reg->guest_phys_addr + reg->memory_size - gpa; 1033 return 0; 1034 } 1035 } 1036 1037 return -EFAULT; 1038 } 1039 1040 int vhost_device_iotlb_miss(struct vhost_dev *dev, uint64_t iova, int write) 1041 { 1042 IOMMUTLBEntry iotlb; 1043 uint64_t uaddr, len; 1044 int ret = -EFAULT; 1045 1046 RCU_READ_LOCK_GUARD(); 1047 1048 trace_vhost_iotlb_miss(dev, 1); 1049 1050 iotlb = address_space_get_iotlb_entry(dev->vdev->dma_as, 1051 iova, write, 1052 MEMTXATTRS_UNSPECIFIED); 1053 if (iotlb.target_as != NULL) { 1054 ret = vhost_memory_region_lookup(dev, iotlb.translated_addr, 1055 &uaddr, &len); 1056 if (ret) { 1057 trace_vhost_iotlb_miss(dev, 3); 1058 error_report("Fail to lookup the translated address " 1059 "%"PRIx64, iotlb.translated_addr); 1060 goto out; 1061 } 1062 1063 len = MIN(iotlb.addr_mask + 1, len); 1064 iova = iova & ~iotlb.addr_mask; 1065 1066 ret = vhost_backend_update_device_iotlb(dev, iova, uaddr, 1067 len, iotlb.perm); 1068 if (ret) { 1069 trace_vhost_iotlb_miss(dev, 4); 1070 error_report("Fail to update device iotlb"); 1071 goto out; 1072 } 1073 } 1074 1075 trace_vhost_iotlb_miss(dev, 2); 1076 1077 out: 1078 return ret; 1079 } 1080 1081 static int vhost_virtqueue_start(struct vhost_dev *dev, 1082 struct VirtIODevice *vdev, 1083 struct vhost_virtqueue *vq, 1084 unsigned idx) 1085 { 1086 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); 1087 VirtioBusState *vbus = VIRTIO_BUS(qbus); 1088 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(vbus); 1089 hwaddr s, l, a; 1090 int r; 1091 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, idx); 1092 struct vhost_vring_file file = { 1093 .index = vhost_vq_index 1094 }; 1095 struct vhost_vring_state state = { 1096 .index = vhost_vq_index 1097 }; 1098 struct VirtQueue *vvq = virtio_get_queue(vdev, idx); 1099 1100 a = virtio_queue_get_desc_addr(vdev, idx); 1101 if (a == 0) { 1102 /* Queue might not be ready for start */ 1103 return 0; 1104 } 1105 1106 vq->num = state.num = virtio_queue_get_num(vdev, idx); 1107 r = dev->vhost_ops->vhost_set_vring_num(dev, &state); 1108 if (r) { 1109 VHOST_OPS_DEBUG("vhost_set_vring_num failed"); 1110 return -errno; 1111 } 1112 1113 state.num = virtio_queue_get_last_avail_idx(vdev, idx); 1114 r = dev->vhost_ops->vhost_set_vring_base(dev, &state); 1115 if (r) { 1116 VHOST_OPS_DEBUG("vhost_set_vring_base failed"); 1117 return -errno; 1118 } 1119 1120 if (vhost_needs_vring_endian(vdev)) { 1121 r = vhost_virtqueue_set_vring_endian_legacy(dev, 1122 virtio_is_big_endian(vdev), 1123 vhost_vq_index); 1124 if (r) { 1125 return -errno; 1126 } 1127 } 1128 1129 vq->desc_size = s = l = virtio_queue_get_desc_size(vdev, idx); 1130 vq->desc_phys = a; 1131 vq->desc = vhost_memory_map(dev, a, &l, false); 1132 if (!vq->desc || l != s) { 1133 r = -ENOMEM; 1134 goto fail_alloc_desc; 1135 } 1136 vq->avail_size = s = l = virtio_queue_get_avail_size(vdev, idx); 1137 vq->avail_phys = a = virtio_queue_get_avail_addr(vdev, idx); 1138 vq->avail = vhost_memory_map(dev, a, &l, false); 1139 if (!vq->avail || l != s) { 1140 r = -ENOMEM; 1141 goto fail_alloc_avail; 1142 } 1143 vq->used_size = s = l = virtio_queue_get_used_size(vdev, idx); 1144 vq->used_phys = a = virtio_queue_get_used_addr(vdev, idx); 1145 vq->used = vhost_memory_map(dev, a, &l, true); 1146 if (!vq->used || l != s) { 1147 r = -ENOMEM; 1148 goto fail_alloc_used; 1149 } 1150 1151 r = vhost_virtqueue_set_addr(dev, vq, vhost_vq_index, dev->log_enabled); 1152 if (r < 0) { 1153 r = -errno; 1154 goto fail_alloc; 1155 } 1156 1157 file.fd = event_notifier_get_fd(virtio_queue_get_host_notifier(vvq)); 1158 r = dev->vhost_ops->vhost_set_vring_kick(dev, &file); 1159 if (r) { 1160 VHOST_OPS_DEBUG("vhost_set_vring_kick failed"); 1161 r = -errno; 1162 goto fail_kick; 1163 } 1164 1165 /* Clear and discard previous events if any. */ 1166 event_notifier_test_and_clear(&vq->masked_notifier); 1167 1168 /* Init vring in unmasked state, unless guest_notifier_mask 1169 * will do it later. 1170 */ 1171 if (!vdev->use_guest_notifier_mask) { 1172 /* TODO: check and handle errors. */ 1173 vhost_virtqueue_mask(dev, vdev, idx, false); 1174 } 1175 1176 if (k->query_guest_notifiers && 1177 k->query_guest_notifiers(qbus->parent) && 1178 virtio_queue_vector(vdev, idx) == VIRTIO_NO_VECTOR) { 1179 file.fd = -1; 1180 r = dev->vhost_ops->vhost_set_vring_call(dev, &file); 1181 if (r) { 1182 goto fail_vector; 1183 } 1184 } 1185 1186 return 0; 1187 1188 fail_vector: 1189 fail_kick: 1190 fail_alloc: 1191 vhost_memory_unmap(dev, vq->used, virtio_queue_get_used_size(vdev, idx), 1192 0, 0); 1193 fail_alloc_used: 1194 vhost_memory_unmap(dev, vq->avail, virtio_queue_get_avail_size(vdev, idx), 1195 0, 0); 1196 fail_alloc_avail: 1197 vhost_memory_unmap(dev, vq->desc, virtio_queue_get_desc_size(vdev, idx), 1198 0, 0); 1199 fail_alloc_desc: 1200 return r; 1201 } 1202 1203 static void vhost_virtqueue_stop(struct vhost_dev *dev, 1204 struct VirtIODevice *vdev, 1205 struct vhost_virtqueue *vq, 1206 unsigned idx) 1207 { 1208 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, idx); 1209 struct vhost_vring_state state = { 1210 .index = vhost_vq_index, 1211 }; 1212 int r; 1213 1214 if (virtio_queue_get_desc_addr(vdev, idx) == 0) { 1215 /* Don't stop the virtqueue which might have not been started */ 1216 return; 1217 } 1218 1219 r = dev->vhost_ops->vhost_get_vring_base(dev, &state); 1220 if (r < 0) { 1221 VHOST_OPS_DEBUG("vhost VQ %u ring restore failed: %d", idx, r); 1222 /* Connection to the backend is broken, so let's sync internal 1223 * last avail idx to the device used idx. 1224 */ 1225 virtio_queue_restore_last_avail_idx(vdev, idx); 1226 } else { 1227 virtio_queue_set_last_avail_idx(vdev, idx, state.num); 1228 } 1229 virtio_queue_invalidate_signalled_used(vdev, idx); 1230 virtio_queue_update_used_idx(vdev, idx); 1231 1232 /* In the cross-endian case, we need to reset the vring endianness to 1233 * native as legacy devices expect so by default. 1234 */ 1235 if (vhost_needs_vring_endian(vdev)) { 1236 vhost_virtqueue_set_vring_endian_legacy(dev, 1237 !virtio_is_big_endian(vdev), 1238 vhost_vq_index); 1239 } 1240 1241 vhost_memory_unmap(dev, vq->used, virtio_queue_get_used_size(vdev, idx), 1242 1, virtio_queue_get_used_size(vdev, idx)); 1243 vhost_memory_unmap(dev, vq->avail, virtio_queue_get_avail_size(vdev, idx), 1244 0, virtio_queue_get_avail_size(vdev, idx)); 1245 vhost_memory_unmap(dev, vq->desc, virtio_queue_get_desc_size(vdev, idx), 1246 0, virtio_queue_get_desc_size(vdev, idx)); 1247 } 1248 1249 static void vhost_eventfd_add(MemoryListener *listener, 1250 MemoryRegionSection *section, 1251 bool match_data, uint64_t data, EventNotifier *e) 1252 { 1253 } 1254 1255 static void vhost_eventfd_del(MemoryListener *listener, 1256 MemoryRegionSection *section, 1257 bool match_data, uint64_t data, EventNotifier *e) 1258 { 1259 } 1260 1261 static int vhost_virtqueue_set_busyloop_timeout(struct vhost_dev *dev, 1262 int n, uint32_t timeout) 1263 { 1264 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, n); 1265 struct vhost_vring_state state = { 1266 .index = vhost_vq_index, 1267 .num = timeout, 1268 }; 1269 int r; 1270 1271 if (!dev->vhost_ops->vhost_set_vring_busyloop_timeout) { 1272 return -EINVAL; 1273 } 1274 1275 r = dev->vhost_ops->vhost_set_vring_busyloop_timeout(dev, &state); 1276 if (r) { 1277 VHOST_OPS_DEBUG("vhost_set_vring_busyloop_timeout failed"); 1278 return r; 1279 } 1280 1281 return 0; 1282 } 1283 1284 static int vhost_virtqueue_init(struct vhost_dev *dev, 1285 struct vhost_virtqueue *vq, int n) 1286 { 1287 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, n); 1288 struct vhost_vring_file file = { 1289 .index = vhost_vq_index, 1290 }; 1291 int r = event_notifier_init(&vq->masked_notifier, 0); 1292 if (r < 0) { 1293 return r; 1294 } 1295 1296 file.fd = event_notifier_get_fd(&vq->masked_notifier); 1297 r = dev->vhost_ops->vhost_set_vring_call(dev, &file); 1298 if (r) { 1299 VHOST_OPS_DEBUG("vhost_set_vring_call failed"); 1300 r = -errno; 1301 goto fail_call; 1302 } 1303 1304 vq->dev = dev; 1305 1306 return 0; 1307 fail_call: 1308 event_notifier_cleanup(&vq->masked_notifier); 1309 return r; 1310 } 1311 1312 static void vhost_virtqueue_cleanup(struct vhost_virtqueue *vq) 1313 { 1314 event_notifier_cleanup(&vq->masked_notifier); 1315 } 1316 1317 int vhost_dev_init(struct vhost_dev *hdev, void *opaque, 1318 VhostBackendType backend_type, uint32_t busyloop_timeout, 1319 Error **errp) 1320 { 1321 uint64_t features; 1322 int i, r, n_initialized_vqs = 0; 1323 1324 hdev->vdev = NULL; 1325 hdev->migration_blocker = NULL; 1326 1327 r = vhost_set_backend_type(hdev, backend_type); 1328 assert(r >= 0); 1329 1330 r = hdev->vhost_ops->vhost_backend_init(hdev, opaque, errp); 1331 if (r < 0) { 1332 goto fail; 1333 } 1334 1335 r = hdev->vhost_ops->vhost_set_owner(hdev); 1336 if (r < 0) { 1337 error_setg_errno(errp, -r, "vhost_set_owner failed"); 1338 goto fail; 1339 } 1340 1341 r = hdev->vhost_ops->vhost_get_features(hdev, &features); 1342 if (r < 0) { 1343 error_setg_errno(errp, -r, "vhost_get_features failed"); 1344 goto fail; 1345 } 1346 1347 for (i = 0; i < hdev->nvqs; ++i, ++n_initialized_vqs) { 1348 r = vhost_virtqueue_init(hdev, hdev->vqs + i, hdev->vq_index + i); 1349 if (r < 0) { 1350 error_setg_errno(errp, -r, "Failed to initialize virtqueue %d", i); 1351 goto fail; 1352 } 1353 } 1354 1355 if (busyloop_timeout) { 1356 for (i = 0; i < hdev->nvqs; ++i) { 1357 r = vhost_virtqueue_set_busyloop_timeout(hdev, hdev->vq_index + i, 1358 busyloop_timeout); 1359 if (r < 0) { 1360 error_setg_errno(errp, -r, "Failed to set busyloop timeout"); 1361 goto fail_busyloop; 1362 } 1363 } 1364 } 1365 1366 hdev->features = features; 1367 1368 hdev->memory_listener = (MemoryListener) { 1369 .name = "vhost", 1370 .begin = vhost_begin, 1371 .commit = vhost_commit, 1372 .region_add = vhost_region_addnop, 1373 .region_nop = vhost_region_addnop, 1374 .log_start = vhost_log_start, 1375 .log_stop = vhost_log_stop, 1376 .log_sync = vhost_log_sync, 1377 .log_global_start = vhost_log_global_start, 1378 .log_global_stop = vhost_log_global_stop, 1379 .eventfd_add = vhost_eventfd_add, 1380 .eventfd_del = vhost_eventfd_del, 1381 .priority = 10 1382 }; 1383 1384 hdev->iommu_listener = (MemoryListener) { 1385 .name = "vhost-iommu", 1386 .region_add = vhost_iommu_region_add, 1387 .region_del = vhost_iommu_region_del, 1388 }; 1389 1390 if (hdev->migration_blocker == NULL) { 1391 if (!(hdev->features & (0x1ULL << VHOST_F_LOG_ALL))) { 1392 error_setg(&hdev->migration_blocker, 1393 "Migration disabled: vhost lacks VHOST_F_LOG_ALL feature."); 1394 } else if (vhost_dev_log_is_shared(hdev) && !qemu_memfd_alloc_check()) { 1395 error_setg(&hdev->migration_blocker, 1396 "Migration disabled: failed to allocate shared memory"); 1397 } 1398 } 1399 1400 if (hdev->migration_blocker != NULL) { 1401 r = migrate_add_blocker(hdev->migration_blocker, errp); 1402 if (r < 0) { 1403 error_free(hdev->migration_blocker); 1404 goto fail_busyloop; 1405 } 1406 } 1407 1408 hdev->mem = g_malloc0(offsetof(struct vhost_memory, regions)); 1409 hdev->n_mem_sections = 0; 1410 hdev->mem_sections = NULL; 1411 hdev->log = NULL; 1412 hdev->log_size = 0; 1413 hdev->log_enabled = false; 1414 hdev->started = false; 1415 memory_listener_register(&hdev->memory_listener, &address_space_memory); 1416 QLIST_INSERT_HEAD(&vhost_devices, hdev, entry); 1417 1418 if (used_memslots > hdev->vhost_ops->vhost_backend_memslots_limit(hdev)) { 1419 error_setg(errp, "vhost backend memory slots limit is less" 1420 " than current number of present memory slots"); 1421 r = -EINVAL; 1422 goto fail_busyloop; 1423 } 1424 1425 return 0; 1426 1427 fail_busyloop: 1428 if (busyloop_timeout) { 1429 while (--i >= 0) { 1430 vhost_virtqueue_set_busyloop_timeout(hdev, hdev->vq_index + i, 0); 1431 } 1432 } 1433 fail: 1434 hdev->nvqs = n_initialized_vqs; 1435 vhost_dev_cleanup(hdev); 1436 return r; 1437 } 1438 1439 void vhost_dev_cleanup(struct vhost_dev *hdev) 1440 { 1441 int i; 1442 1443 for (i = 0; i < hdev->nvqs; ++i) { 1444 vhost_virtqueue_cleanup(hdev->vqs + i); 1445 } 1446 if (hdev->mem) { 1447 /* those are only safe after successful init */ 1448 memory_listener_unregister(&hdev->memory_listener); 1449 QLIST_REMOVE(hdev, entry); 1450 } 1451 if (hdev->migration_blocker) { 1452 migrate_del_blocker(hdev->migration_blocker); 1453 error_free(hdev->migration_blocker); 1454 } 1455 g_free(hdev->mem); 1456 g_free(hdev->mem_sections); 1457 if (hdev->vhost_ops) { 1458 hdev->vhost_ops->vhost_backend_cleanup(hdev); 1459 } 1460 assert(!hdev->log); 1461 1462 memset(hdev, 0, sizeof(struct vhost_dev)); 1463 } 1464 1465 /* Stop processing guest IO notifications in qemu. 1466 * Start processing them in vhost in kernel. 1467 */ 1468 int vhost_dev_enable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev) 1469 { 1470 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); 1471 int i, r, e; 1472 1473 /* We will pass the notifiers to the kernel, make sure that QEMU 1474 * doesn't interfere. 1475 */ 1476 r = virtio_device_grab_ioeventfd(vdev); 1477 if (r < 0) { 1478 error_report("binding does not support host notifiers"); 1479 goto fail; 1480 } 1481 1482 for (i = 0; i < hdev->nvqs; ++i) { 1483 r = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i, 1484 true); 1485 if (r < 0) { 1486 error_report("vhost VQ %d notifier binding failed: %d", i, -r); 1487 goto fail_vq; 1488 } 1489 } 1490 1491 return 0; 1492 fail_vq: 1493 while (--i >= 0) { 1494 e = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i, 1495 false); 1496 if (e < 0) { 1497 error_report("vhost VQ %d notifier cleanup error: %d", i, -r); 1498 } 1499 assert (e >= 0); 1500 virtio_bus_cleanup_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i); 1501 } 1502 virtio_device_release_ioeventfd(vdev); 1503 fail: 1504 return r; 1505 } 1506 1507 /* Stop processing guest IO notifications in vhost. 1508 * Start processing them in qemu. 1509 * This might actually run the qemu handlers right away, 1510 * so virtio in qemu must be completely setup when this is called. 1511 */ 1512 void vhost_dev_disable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev) 1513 { 1514 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); 1515 int i, r; 1516 1517 for (i = 0; i < hdev->nvqs; ++i) { 1518 r = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i, 1519 false); 1520 if (r < 0) { 1521 error_report("vhost VQ %d notifier cleanup failed: %d", i, -r); 1522 } 1523 assert (r >= 0); 1524 virtio_bus_cleanup_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i); 1525 } 1526 virtio_device_release_ioeventfd(vdev); 1527 } 1528 1529 /* Test and clear event pending status. 1530 * Should be called after unmask to avoid losing events. 1531 */ 1532 bool vhost_virtqueue_pending(struct vhost_dev *hdev, int n) 1533 { 1534 struct vhost_virtqueue *vq = hdev->vqs + n - hdev->vq_index; 1535 assert(n >= hdev->vq_index && n < hdev->vq_index + hdev->nvqs); 1536 return event_notifier_test_and_clear(&vq->masked_notifier); 1537 } 1538 1539 /* Mask/unmask events from this vq. */ 1540 void vhost_virtqueue_mask(struct vhost_dev *hdev, VirtIODevice *vdev, int n, 1541 bool mask) 1542 { 1543 struct VirtQueue *vvq = virtio_get_queue(vdev, n); 1544 int r, index = n - hdev->vq_index; 1545 struct vhost_vring_file file; 1546 1547 /* should only be called after backend is connected */ 1548 assert(hdev->vhost_ops); 1549 1550 if (mask) { 1551 assert(vdev->use_guest_notifier_mask); 1552 file.fd = event_notifier_get_fd(&hdev->vqs[index].masked_notifier); 1553 } else { 1554 file.fd = event_notifier_get_fd(virtio_queue_get_guest_notifier(vvq)); 1555 } 1556 1557 file.index = hdev->vhost_ops->vhost_get_vq_index(hdev, n); 1558 r = hdev->vhost_ops->vhost_set_vring_call(hdev, &file); 1559 if (r < 0) { 1560 VHOST_OPS_DEBUG("vhost_set_vring_call failed"); 1561 } 1562 } 1563 1564 uint64_t vhost_get_features(struct vhost_dev *hdev, const int *feature_bits, 1565 uint64_t features) 1566 { 1567 const int *bit = feature_bits; 1568 while (*bit != VHOST_INVALID_FEATURE_BIT) { 1569 uint64_t bit_mask = (1ULL << *bit); 1570 if (!(hdev->features & bit_mask)) { 1571 features &= ~bit_mask; 1572 } 1573 bit++; 1574 } 1575 return features; 1576 } 1577 1578 void vhost_ack_features(struct vhost_dev *hdev, const int *feature_bits, 1579 uint64_t features) 1580 { 1581 const int *bit = feature_bits; 1582 while (*bit != VHOST_INVALID_FEATURE_BIT) { 1583 uint64_t bit_mask = (1ULL << *bit); 1584 if (features & bit_mask) { 1585 hdev->acked_features |= bit_mask; 1586 } 1587 bit++; 1588 } 1589 } 1590 1591 int vhost_dev_get_config(struct vhost_dev *hdev, uint8_t *config, 1592 uint32_t config_len, Error **errp) 1593 { 1594 assert(hdev->vhost_ops); 1595 1596 if (hdev->vhost_ops->vhost_get_config) { 1597 return hdev->vhost_ops->vhost_get_config(hdev, config, config_len, 1598 errp); 1599 } 1600 1601 error_setg(errp, "vhost_get_config not implemented"); 1602 return -ENOTSUP; 1603 } 1604 1605 int vhost_dev_set_config(struct vhost_dev *hdev, const uint8_t *data, 1606 uint32_t offset, uint32_t size, uint32_t flags) 1607 { 1608 assert(hdev->vhost_ops); 1609 1610 if (hdev->vhost_ops->vhost_set_config) { 1611 return hdev->vhost_ops->vhost_set_config(hdev, data, offset, 1612 size, flags); 1613 } 1614 1615 return -1; 1616 } 1617 1618 void vhost_dev_set_config_notifier(struct vhost_dev *hdev, 1619 const VhostDevConfigOps *ops) 1620 { 1621 hdev->config_ops = ops; 1622 } 1623 1624 void vhost_dev_free_inflight(struct vhost_inflight *inflight) 1625 { 1626 if (inflight && inflight->addr) { 1627 qemu_memfd_free(inflight->addr, inflight->size, inflight->fd); 1628 inflight->addr = NULL; 1629 inflight->fd = -1; 1630 } 1631 } 1632 1633 static int vhost_dev_resize_inflight(struct vhost_inflight *inflight, 1634 uint64_t new_size) 1635 { 1636 Error *err = NULL; 1637 int fd = -1; 1638 void *addr = qemu_memfd_alloc("vhost-inflight", new_size, 1639 F_SEAL_GROW | F_SEAL_SHRINK | F_SEAL_SEAL, 1640 &fd, &err); 1641 1642 if (err) { 1643 error_report_err(err); 1644 return -1; 1645 } 1646 1647 vhost_dev_free_inflight(inflight); 1648 inflight->offset = 0; 1649 inflight->addr = addr; 1650 inflight->fd = fd; 1651 inflight->size = new_size; 1652 1653 return 0; 1654 } 1655 1656 void vhost_dev_save_inflight(struct vhost_inflight *inflight, QEMUFile *f) 1657 { 1658 if (inflight->addr) { 1659 qemu_put_be64(f, inflight->size); 1660 qemu_put_be16(f, inflight->queue_size); 1661 qemu_put_buffer(f, inflight->addr, inflight->size); 1662 } else { 1663 qemu_put_be64(f, 0); 1664 } 1665 } 1666 1667 int vhost_dev_load_inflight(struct vhost_inflight *inflight, QEMUFile *f) 1668 { 1669 uint64_t size; 1670 1671 size = qemu_get_be64(f); 1672 if (!size) { 1673 return 0; 1674 } 1675 1676 if (inflight->size != size) { 1677 if (vhost_dev_resize_inflight(inflight, size)) { 1678 return -1; 1679 } 1680 } 1681 inflight->queue_size = qemu_get_be16(f); 1682 1683 qemu_get_buffer(f, inflight->addr, size); 1684 1685 return 0; 1686 } 1687 1688 int vhost_dev_prepare_inflight(struct vhost_dev *hdev, VirtIODevice *vdev) 1689 { 1690 int r; 1691 1692 if (hdev->vhost_ops->vhost_get_inflight_fd == NULL || 1693 hdev->vhost_ops->vhost_set_inflight_fd == NULL) { 1694 return 0; 1695 } 1696 1697 hdev->vdev = vdev; 1698 1699 r = vhost_dev_set_features(hdev, hdev->log_enabled); 1700 if (r < 0) { 1701 VHOST_OPS_DEBUG("vhost_dev_prepare_inflight failed"); 1702 return r; 1703 } 1704 1705 return 0; 1706 } 1707 1708 int vhost_dev_set_inflight(struct vhost_dev *dev, 1709 struct vhost_inflight *inflight) 1710 { 1711 int r; 1712 1713 if (dev->vhost_ops->vhost_set_inflight_fd && inflight->addr) { 1714 r = dev->vhost_ops->vhost_set_inflight_fd(dev, inflight); 1715 if (r) { 1716 VHOST_OPS_DEBUG("vhost_set_inflight_fd failed"); 1717 return -errno; 1718 } 1719 } 1720 1721 return 0; 1722 } 1723 1724 int vhost_dev_get_inflight(struct vhost_dev *dev, uint16_t queue_size, 1725 struct vhost_inflight *inflight) 1726 { 1727 int r; 1728 1729 if (dev->vhost_ops->vhost_get_inflight_fd) { 1730 r = dev->vhost_ops->vhost_get_inflight_fd(dev, queue_size, inflight); 1731 if (r) { 1732 VHOST_OPS_DEBUG("vhost_get_inflight_fd failed"); 1733 return -errno; 1734 } 1735 } 1736 1737 return 0; 1738 } 1739 1740 /* Host notifiers must be enabled at this point. */ 1741 int vhost_dev_start(struct vhost_dev *hdev, VirtIODevice *vdev) 1742 { 1743 int i, r; 1744 1745 /* should only be called after backend is connected */ 1746 assert(hdev->vhost_ops); 1747 1748 hdev->started = true; 1749 hdev->vdev = vdev; 1750 1751 r = vhost_dev_set_features(hdev, hdev->log_enabled); 1752 if (r < 0) { 1753 goto fail_features; 1754 } 1755 1756 if (vhost_dev_has_iommu(hdev)) { 1757 memory_listener_register(&hdev->iommu_listener, vdev->dma_as); 1758 } 1759 1760 r = hdev->vhost_ops->vhost_set_mem_table(hdev, hdev->mem); 1761 if (r < 0) { 1762 VHOST_OPS_DEBUG("vhost_set_mem_table failed"); 1763 r = -errno; 1764 goto fail_mem; 1765 } 1766 for (i = 0; i < hdev->nvqs; ++i) { 1767 r = vhost_virtqueue_start(hdev, 1768 vdev, 1769 hdev->vqs + i, 1770 hdev->vq_index + i); 1771 if (r < 0) { 1772 goto fail_vq; 1773 } 1774 } 1775 1776 if (hdev->log_enabled) { 1777 uint64_t log_base; 1778 1779 hdev->log_size = vhost_get_log_size(hdev); 1780 hdev->log = vhost_log_get(hdev->log_size, 1781 vhost_dev_log_is_shared(hdev)); 1782 log_base = (uintptr_t)hdev->log->log; 1783 r = hdev->vhost_ops->vhost_set_log_base(hdev, 1784 hdev->log_size ? log_base : 0, 1785 hdev->log); 1786 if (r < 0) { 1787 VHOST_OPS_DEBUG("vhost_set_log_base failed"); 1788 r = -errno; 1789 goto fail_log; 1790 } 1791 } 1792 if (hdev->vhost_ops->vhost_dev_start) { 1793 r = hdev->vhost_ops->vhost_dev_start(hdev, true); 1794 if (r) { 1795 goto fail_log; 1796 } 1797 } 1798 if (vhost_dev_has_iommu(hdev) && 1799 hdev->vhost_ops->vhost_set_iotlb_callback) { 1800 hdev->vhost_ops->vhost_set_iotlb_callback(hdev, true); 1801 1802 /* Update used ring information for IOTLB to work correctly, 1803 * vhost-kernel code requires for this.*/ 1804 for (i = 0; i < hdev->nvqs; ++i) { 1805 struct vhost_virtqueue *vq = hdev->vqs + i; 1806 vhost_device_iotlb_miss(hdev, vq->used_phys, true); 1807 } 1808 } 1809 return 0; 1810 fail_log: 1811 vhost_log_put(hdev, false); 1812 fail_vq: 1813 while (--i >= 0) { 1814 vhost_virtqueue_stop(hdev, 1815 vdev, 1816 hdev->vqs + i, 1817 hdev->vq_index + i); 1818 } 1819 1820 fail_mem: 1821 fail_features: 1822 1823 hdev->started = false; 1824 return r; 1825 } 1826 1827 /* Host notifiers must be enabled at this point. */ 1828 void vhost_dev_stop(struct vhost_dev *hdev, VirtIODevice *vdev) 1829 { 1830 int i; 1831 1832 /* should only be called after backend is connected */ 1833 assert(hdev->vhost_ops); 1834 1835 if (hdev->vhost_ops->vhost_dev_start) { 1836 hdev->vhost_ops->vhost_dev_start(hdev, false); 1837 } 1838 for (i = 0; i < hdev->nvqs; ++i) { 1839 vhost_virtqueue_stop(hdev, 1840 vdev, 1841 hdev->vqs + i, 1842 hdev->vq_index + i); 1843 } 1844 1845 if (vhost_dev_has_iommu(hdev)) { 1846 if (hdev->vhost_ops->vhost_set_iotlb_callback) { 1847 hdev->vhost_ops->vhost_set_iotlb_callback(hdev, false); 1848 } 1849 memory_listener_unregister(&hdev->iommu_listener); 1850 } 1851 vhost_log_put(hdev, true); 1852 hdev->started = false; 1853 hdev->vdev = NULL; 1854 } 1855 1856 int vhost_net_set_backend(struct vhost_dev *hdev, 1857 struct vhost_vring_file *file) 1858 { 1859 if (hdev->vhost_ops->vhost_net_set_backend) { 1860 return hdev->vhost_ops->vhost_net_set_backend(hdev, file); 1861 } 1862 1863 return -1; 1864 } 1865