1 /* 2 * vhost support 3 * 4 * Copyright Red Hat, Inc. 2010 5 * 6 * Authors: 7 * Michael S. Tsirkin <mst@redhat.com> 8 * 9 * This work is licensed under the terms of the GNU GPL, version 2. See 10 * the COPYING file in the top-level directory. 11 * 12 * Contributions after 2012-01-13 are licensed under the terms of the 13 * GNU GPL, version 2 or (at your option) any later version. 14 */ 15 16 #include "qemu/osdep.h" 17 #include "qapi/error.h" 18 #include "hw/virtio/vhost.h" 19 #include "qemu/atomic.h" 20 #include "qemu/range.h" 21 #include "qemu/error-report.h" 22 #include "qemu/memfd.h" 23 #include "standard-headers/linux/vhost_types.h" 24 #include "exec/address-spaces.h" 25 #include "hw/virtio/virtio-bus.h" 26 #include "hw/virtio/virtio-access.h" 27 #include "migration/blocker.h" 28 #include "migration/qemu-file-types.h" 29 #include "sysemu/dma.h" 30 #include "trace.h" 31 32 /* enabled until disconnected backend stabilizes */ 33 #define _VHOST_DEBUG 1 34 35 #ifdef _VHOST_DEBUG 36 #define VHOST_OPS_DEBUG(fmt, ...) \ 37 do { error_report(fmt ": %s (%d)", ## __VA_ARGS__, \ 38 strerror(errno), errno); } while (0) 39 #else 40 #define VHOST_OPS_DEBUG(fmt, ...) \ 41 do { } while (0) 42 #endif 43 44 static struct vhost_log *vhost_log; 45 static struct vhost_log *vhost_log_shm; 46 47 static unsigned int used_memslots; 48 static QLIST_HEAD(, vhost_dev) vhost_devices = 49 QLIST_HEAD_INITIALIZER(vhost_devices); 50 51 bool vhost_has_free_slot(void) 52 { 53 unsigned int slots_limit = ~0U; 54 struct vhost_dev *hdev; 55 56 QLIST_FOREACH(hdev, &vhost_devices, entry) { 57 unsigned int r = hdev->vhost_ops->vhost_backend_memslots_limit(hdev); 58 slots_limit = MIN(slots_limit, r); 59 } 60 return slots_limit > used_memslots; 61 } 62 63 static void vhost_dev_sync_region(struct vhost_dev *dev, 64 MemoryRegionSection *section, 65 uint64_t mfirst, uint64_t mlast, 66 uint64_t rfirst, uint64_t rlast) 67 { 68 vhost_log_chunk_t *log = dev->log->log; 69 70 uint64_t start = MAX(mfirst, rfirst); 71 uint64_t end = MIN(mlast, rlast); 72 vhost_log_chunk_t *from = log + start / VHOST_LOG_CHUNK; 73 vhost_log_chunk_t *to = log + end / VHOST_LOG_CHUNK + 1; 74 uint64_t addr = QEMU_ALIGN_DOWN(start, VHOST_LOG_CHUNK); 75 76 if (end < start) { 77 return; 78 } 79 assert(end / VHOST_LOG_CHUNK < dev->log_size); 80 assert(start / VHOST_LOG_CHUNK < dev->log_size); 81 82 for (;from < to; ++from) { 83 vhost_log_chunk_t log; 84 /* We first check with non-atomic: much cheaper, 85 * and we expect non-dirty to be the common case. */ 86 if (!*from) { 87 addr += VHOST_LOG_CHUNK; 88 continue; 89 } 90 /* Data must be read atomically. We don't really need barrier semantics 91 * but it's easier to use atomic_* than roll our own. */ 92 log = atomic_xchg(from, 0); 93 while (log) { 94 int bit = ctzl(log); 95 hwaddr page_addr; 96 hwaddr section_offset; 97 hwaddr mr_offset; 98 page_addr = addr + bit * VHOST_LOG_PAGE; 99 section_offset = page_addr - section->offset_within_address_space; 100 mr_offset = section_offset + section->offset_within_region; 101 memory_region_set_dirty(section->mr, mr_offset, VHOST_LOG_PAGE); 102 log &= ~(0x1ull << bit); 103 } 104 addr += VHOST_LOG_CHUNK; 105 } 106 } 107 108 static int vhost_sync_dirty_bitmap(struct vhost_dev *dev, 109 MemoryRegionSection *section, 110 hwaddr first, 111 hwaddr last) 112 { 113 int i; 114 hwaddr start_addr; 115 hwaddr end_addr; 116 117 if (!dev->log_enabled || !dev->started) { 118 return 0; 119 } 120 start_addr = section->offset_within_address_space; 121 end_addr = range_get_last(start_addr, int128_get64(section->size)); 122 start_addr = MAX(first, start_addr); 123 end_addr = MIN(last, end_addr); 124 125 for (i = 0; i < dev->mem->nregions; ++i) { 126 struct vhost_memory_region *reg = dev->mem->regions + i; 127 vhost_dev_sync_region(dev, section, start_addr, end_addr, 128 reg->guest_phys_addr, 129 range_get_last(reg->guest_phys_addr, 130 reg->memory_size)); 131 } 132 for (i = 0; i < dev->nvqs; ++i) { 133 struct vhost_virtqueue *vq = dev->vqs + i; 134 135 if (!vq->used_phys && !vq->used_size) { 136 continue; 137 } 138 139 vhost_dev_sync_region(dev, section, start_addr, end_addr, vq->used_phys, 140 range_get_last(vq->used_phys, vq->used_size)); 141 } 142 return 0; 143 } 144 145 static void vhost_log_sync(MemoryListener *listener, 146 MemoryRegionSection *section) 147 { 148 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 149 memory_listener); 150 vhost_sync_dirty_bitmap(dev, section, 0x0, ~0x0ULL); 151 } 152 153 static void vhost_log_sync_range(struct vhost_dev *dev, 154 hwaddr first, hwaddr last) 155 { 156 int i; 157 /* FIXME: this is N^2 in number of sections */ 158 for (i = 0; i < dev->n_mem_sections; ++i) { 159 MemoryRegionSection *section = &dev->mem_sections[i]; 160 vhost_sync_dirty_bitmap(dev, section, first, last); 161 } 162 } 163 164 static uint64_t vhost_get_log_size(struct vhost_dev *dev) 165 { 166 uint64_t log_size = 0; 167 int i; 168 for (i = 0; i < dev->mem->nregions; ++i) { 169 struct vhost_memory_region *reg = dev->mem->regions + i; 170 uint64_t last = range_get_last(reg->guest_phys_addr, 171 reg->memory_size); 172 log_size = MAX(log_size, last / VHOST_LOG_CHUNK + 1); 173 } 174 for (i = 0; i < dev->nvqs; ++i) { 175 struct vhost_virtqueue *vq = dev->vqs + i; 176 177 if (!vq->used_phys && !vq->used_size) { 178 continue; 179 } 180 181 uint64_t last = vq->used_phys + vq->used_size - 1; 182 log_size = MAX(log_size, last / VHOST_LOG_CHUNK + 1); 183 } 184 return log_size; 185 } 186 187 static struct vhost_log *vhost_log_alloc(uint64_t size, bool share) 188 { 189 Error *err = NULL; 190 struct vhost_log *log; 191 uint64_t logsize = size * sizeof(*(log->log)); 192 int fd = -1; 193 194 log = g_new0(struct vhost_log, 1); 195 if (share) { 196 log->log = qemu_memfd_alloc("vhost-log", logsize, 197 F_SEAL_GROW | F_SEAL_SHRINK | F_SEAL_SEAL, 198 &fd, &err); 199 if (err) { 200 error_report_err(err); 201 g_free(log); 202 return NULL; 203 } 204 memset(log->log, 0, logsize); 205 } else { 206 log->log = g_malloc0(logsize); 207 } 208 209 log->size = size; 210 log->refcnt = 1; 211 log->fd = fd; 212 213 return log; 214 } 215 216 static struct vhost_log *vhost_log_get(uint64_t size, bool share) 217 { 218 struct vhost_log *log = share ? vhost_log_shm : vhost_log; 219 220 if (!log || log->size != size) { 221 log = vhost_log_alloc(size, share); 222 if (share) { 223 vhost_log_shm = log; 224 } else { 225 vhost_log = log; 226 } 227 } else { 228 ++log->refcnt; 229 } 230 231 return log; 232 } 233 234 static void vhost_log_put(struct vhost_dev *dev, bool sync) 235 { 236 struct vhost_log *log = dev->log; 237 238 if (!log) { 239 return; 240 } 241 242 --log->refcnt; 243 if (log->refcnt == 0) { 244 /* Sync only the range covered by the old log */ 245 if (dev->log_size && sync) { 246 vhost_log_sync_range(dev, 0, dev->log_size * VHOST_LOG_CHUNK - 1); 247 } 248 249 if (vhost_log == log) { 250 g_free(log->log); 251 vhost_log = NULL; 252 } else if (vhost_log_shm == log) { 253 qemu_memfd_free(log->log, log->size * sizeof(*(log->log)), 254 log->fd); 255 vhost_log_shm = NULL; 256 } 257 258 g_free(log); 259 } 260 261 dev->log = NULL; 262 dev->log_size = 0; 263 } 264 265 static bool vhost_dev_log_is_shared(struct vhost_dev *dev) 266 { 267 return dev->vhost_ops->vhost_requires_shm_log && 268 dev->vhost_ops->vhost_requires_shm_log(dev); 269 } 270 271 static inline void vhost_dev_log_resize(struct vhost_dev *dev, uint64_t size) 272 { 273 struct vhost_log *log = vhost_log_get(size, vhost_dev_log_is_shared(dev)); 274 uint64_t log_base = (uintptr_t)log->log; 275 int r; 276 277 /* inform backend of log switching, this must be done before 278 releasing the current log, to ensure no logging is lost */ 279 r = dev->vhost_ops->vhost_set_log_base(dev, log_base, log); 280 if (r < 0) { 281 VHOST_OPS_DEBUG("vhost_set_log_base failed"); 282 } 283 284 vhost_log_put(dev, true); 285 dev->log = log; 286 dev->log_size = size; 287 } 288 289 static int vhost_dev_has_iommu(struct vhost_dev *dev) 290 { 291 VirtIODevice *vdev = dev->vdev; 292 293 return virtio_host_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM); 294 } 295 296 static void *vhost_memory_map(struct vhost_dev *dev, hwaddr addr, 297 hwaddr *plen, int is_write) 298 { 299 if (!vhost_dev_has_iommu(dev)) { 300 return cpu_physical_memory_map(addr, plen, is_write); 301 } else { 302 return (void *)(uintptr_t)addr; 303 } 304 } 305 306 static void vhost_memory_unmap(struct vhost_dev *dev, void *buffer, 307 hwaddr len, int is_write, 308 hwaddr access_len) 309 { 310 if (!vhost_dev_has_iommu(dev)) { 311 cpu_physical_memory_unmap(buffer, len, is_write, access_len); 312 } 313 } 314 315 static int vhost_verify_ring_part_mapping(void *ring_hva, 316 uint64_t ring_gpa, 317 uint64_t ring_size, 318 void *reg_hva, 319 uint64_t reg_gpa, 320 uint64_t reg_size) 321 { 322 uint64_t hva_ring_offset; 323 uint64_t ring_last = range_get_last(ring_gpa, ring_size); 324 uint64_t reg_last = range_get_last(reg_gpa, reg_size); 325 326 if (ring_last < reg_gpa || ring_gpa > reg_last) { 327 return 0; 328 } 329 /* check that whole ring's is mapped */ 330 if (ring_last > reg_last) { 331 return -ENOMEM; 332 } 333 /* check that ring's MemoryRegion wasn't replaced */ 334 hva_ring_offset = ring_gpa - reg_gpa; 335 if (ring_hva != reg_hva + hva_ring_offset) { 336 return -EBUSY; 337 } 338 339 return 0; 340 } 341 342 static int vhost_verify_ring_mappings(struct vhost_dev *dev, 343 void *reg_hva, 344 uint64_t reg_gpa, 345 uint64_t reg_size) 346 { 347 int i, j; 348 int r = 0; 349 const char *part_name[] = { 350 "descriptor table", 351 "available ring", 352 "used ring" 353 }; 354 355 if (vhost_dev_has_iommu(dev)) { 356 return 0; 357 } 358 359 for (i = 0; i < dev->nvqs; ++i) { 360 struct vhost_virtqueue *vq = dev->vqs + i; 361 362 if (vq->desc_phys == 0) { 363 continue; 364 } 365 366 j = 0; 367 r = vhost_verify_ring_part_mapping( 368 vq->desc, vq->desc_phys, vq->desc_size, 369 reg_hva, reg_gpa, reg_size); 370 if (r) { 371 break; 372 } 373 374 j++; 375 r = vhost_verify_ring_part_mapping( 376 vq->avail, vq->avail_phys, vq->avail_size, 377 reg_hva, reg_gpa, reg_size); 378 if (r) { 379 break; 380 } 381 382 j++; 383 r = vhost_verify_ring_part_mapping( 384 vq->used, vq->used_phys, vq->used_size, 385 reg_hva, reg_gpa, reg_size); 386 if (r) { 387 break; 388 } 389 } 390 391 if (r == -ENOMEM) { 392 error_report("Unable to map %s for ring %d", part_name[j], i); 393 } else if (r == -EBUSY) { 394 error_report("%s relocated for ring %d", part_name[j], i); 395 } 396 return r; 397 } 398 399 static bool vhost_section(struct vhost_dev *dev, MemoryRegionSection *section) 400 { 401 bool result; 402 bool log_dirty = memory_region_get_dirty_log_mask(section->mr) & 403 ~(1 << DIRTY_MEMORY_MIGRATION); 404 result = memory_region_is_ram(section->mr) && 405 !memory_region_is_rom(section->mr); 406 407 /* Vhost doesn't handle any block which is doing dirty-tracking other 408 * than migration; this typically fires on VGA areas. 409 */ 410 result &= !log_dirty; 411 412 if (result && dev->vhost_ops->vhost_backend_mem_section_filter) { 413 result &= 414 dev->vhost_ops->vhost_backend_mem_section_filter(dev, section); 415 } 416 417 trace_vhost_section(section->mr->name, result); 418 return result; 419 } 420 421 static void vhost_begin(MemoryListener *listener) 422 { 423 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 424 memory_listener); 425 dev->tmp_sections = NULL; 426 dev->n_tmp_sections = 0; 427 } 428 429 static void vhost_commit(MemoryListener *listener) 430 { 431 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 432 memory_listener); 433 MemoryRegionSection *old_sections; 434 int n_old_sections; 435 uint64_t log_size; 436 size_t regions_size; 437 int r; 438 int i; 439 bool changed = false; 440 441 /* Note we can be called before the device is started, but then 442 * starting the device calls set_mem_table, so we need to have 443 * built the data structures. 444 */ 445 old_sections = dev->mem_sections; 446 n_old_sections = dev->n_mem_sections; 447 dev->mem_sections = dev->tmp_sections; 448 dev->n_mem_sections = dev->n_tmp_sections; 449 450 if (dev->n_mem_sections != n_old_sections) { 451 changed = true; 452 } else { 453 /* Same size, lets check the contents */ 454 for (int i = 0; i < n_old_sections; i++) { 455 if (!MemoryRegionSection_eq(&old_sections[i], 456 &dev->mem_sections[i])) { 457 changed = true; 458 break; 459 } 460 } 461 } 462 463 trace_vhost_commit(dev->started, changed); 464 if (!changed) { 465 goto out; 466 } 467 468 /* Rebuild the regions list from the new sections list */ 469 regions_size = offsetof(struct vhost_memory, regions) + 470 dev->n_mem_sections * sizeof dev->mem->regions[0]; 471 dev->mem = g_realloc(dev->mem, regions_size); 472 dev->mem->nregions = dev->n_mem_sections; 473 used_memslots = dev->mem->nregions; 474 for (i = 0; i < dev->n_mem_sections; i++) { 475 struct vhost_memory_region *cur_vmr = dev->mem->regions + i; 476 struct MemoryRegionSection *mrs = dev->mem_sections + i; 477 478 cur_vmr->guest_phys_addr = mrs->offset_within_address_space; 479 cur_vmr->memory_size = int128_get64(mrs->size); 480 cur_vmr->userspace_addr = 481 (uintptr_t)memory_region_get_ram_ptr(mrs->mr) + 482 mrs->offset_within_region; 483 cur_vmr->flags_padding = 0; 484 } 485 486 if (!dev->started) { 487 goto out; 488 } 489 490 for (i = 0; i < dev->mem->nregions; i++) { 491 if (vhost_verify_ring_mappings(dev, 492 (void *)(uintptr_t)dev->mem->regions[i].userspace_addr, 493 dev->mem->regions[i].guest_phys_addr, 494 dev->mem->regions[i].memory_size)) { 495 error_report("Verify ring failure on region %d", i); 496 abort(); 497 } 498 } 499 500 if (!dev->log_enabled) { 501 r = dev->vhost_ops->vhost_set_mem_table(dev, dev->mem); 502 if (r < 0) { 503 VHOST_OPS_DEBUG("vhost_set_mem_table failed"); 504 } 505 goto out; 506 } 507 log_size = vhost_get_log_size(dev); 508 /* We allocate an extra 4K bytes to log, 509 * to reduce the * number of reallocations. */ 510 #define VHOST_LOG_BUFFER (0x1000 / sizeof *dev->log) 511 /* To log more, must increase log size before table update. */ 512 if (dev->log_size < log_size) { 513 vhost_dev_log_resize(dev, log_size + VHOST_LOG_BUFFER); 514 } 515 r = dev->vhost_ops->vhost_set_mem_table(dev, dev->mem); 516 if (r < 0) { 517 VHOST_OPS_DEBUG("vhost_set_mem_table failed"); 518 } 519 /* To log less, can only decrease log size after table update. */ 520 if (dev->log_size > log_size + VHOST_LOG_BUFFER) { 521 vhost_dev_log_resize(dev, log_size); 522 } 523 524 out: 525 /* Deref the old list of sections, this must happen _after_ the 526 * vhost_set_mem_table to ensure the client isn't still using the 527 * section we're about to unref. 528 */ 529 while (n_old_sections--) { 530 memory_region_unref(old_sections[n_old_sections].mr); 531 } 532 g_free(old_sections); 533 return; 534 } 535 536 /* Adds the section data to the tmp_section structure. 537 * It relies on the listener calling us in memory address order 538 * and for each region (via the _add and _nop methods) to 539 * join neighbours. 540 */ 541 static void vhost_region_add_section(struct vhost_dev *dev, 542 MemoryRegionSection *section) 543 { 544 bool need_add = true; 545 uint64_t mrs_size = int128_get64(section->size); 546 uint64_t mrs_gpa = section->offset_within_address_space; 547 uintptr_t mrs_host = (uintptr_t)memory_region_get_ram_ptr(section->mr) + 548 section->offset_within_region; 549 RAMBlock *mrs_rb = section->mr->ram_block; 550 size_t mrs_page = qemu_ram_pagesize(mrs_rb); 551 552 trace_vhost_region_add_section(section->mr->name, mrs_gpa, mrs_size, 553 mrs_host); 554 555 /* Round the section to it's page size */ 556 /* First align the start down to a page boundary */ 557 uint64_t alignage = mrs_host & (mrs_page - 1); 558 if (alignage) { 559 mrs_host -= alignage; 560 mrs_size += alignage; 561 mrs_gpa -= alignage; 562 } 563 /* Now align the size up to a page boundary */ 564 alignage = mrs_size & (mrs_page - 1); 565 if (alignage) { 566 mrs_size += mrs_page - alignage; 567 } 568 trace_vhost_region_add_section_aligned(section->mr->name, mrs_gpa, mrs_size, 569 mrs_host); 570 571 if (dev->n_tmp_sections) { 572 /* Since we already have at least one section, lets see if 573 * this extends it; since we're scanning in order, we only 574 * have to look at the last one, and the FlatView that calls 575 * us shouldn't have overlaps. 576 */ 577 MemoryRegionSection *prev_sec = dev->tmp_sections + 578 (dev->n_tmp_sections - 1); 579 uint64_t prev_gpa_start = prev_sec->offset_within_address_space; 580 uint64_t prev_size = int128_get64(prev_sec->size); 581 uint64_t prev_gpa_end = range_get_last(prev_gpa_start, prev_size); 582 uint64_t prev_host_start = 583 (uintptr_t)memory_region_get_ram_ptr(prev_sec->mr) + 584 prev_sec->offset_within_region; 585 uint64_t prev_host_end = range_get_last(prev_host_start, prev_size); 586 587 if (mrs_gpa <= (prev_gpa_end + 1)) { 588 /* OK, looks like overlapping/intersecting - it's possible that 589 * the rounding to page sizes has made them overlap, but they should 590 * match up in the same RAMBlock if they do. 591 */ 592 if (mrs_gpa < prev_gpa_start) { 593 error_report("%s:Section '%s' rounded to %"PRIx64 594 " prior to previous '%s' %"PRIx64, 595 __func__, section->mr->name, mrs_gpa, 596 prev_sec->mr->name, prev_gpa_start); 597 /* A way to cleanly fail here would be better */ 598 return; 599 } 600 /* Offset from the start of the previous GPA to this GPA */ 601 size_t offset = mrs_gpa - prev_gpa_start; 602 603 if (prev_host_start + offset == mrs_host && 604 section->mr == prev_sec->mr && 605 (!dev->vhost_ops->vhost_backend_can_merge || 606 dev->vhost_ops->vhost_backend_can_merge(dev, 607 mrs_host, mrs_size, 608 prev_host_start, prev_size))) { 609 uint64_t max_end = MAX(prev_host_end, mrs_host + mrs_size); 610 need_add = false; 611 prev_sec->offset_within_address_space = 612 MIN(prev_gpa_start, mrs_gpa); 613 prev_sec->offset_within_region = 614 MIN(prev_host_start, mrs_host) - 615 (uintptr_t)memory_region_get_ram_ptr(prev_sec->mr); 616 prev_sec->size = int128_make64(max_end - MIN(prev_host_start, 617 mrs_host)); 618 trace_vhost_region_add_section_merge(section->mr->name, 619 int128_get64(prev_sec->size), 620 prev_sec->offset_within_address_space, 621 prev_sec->offset_within_region); 622 } else { 623 /* adjoining regions are fine, but overlapping ones with 624 * different blocks/offsets shouldn't happen 625 */ 626 if (mrs_gpa != prev_gpa_end + 1) { 627 error_report("%s: Overlapping but not coherent sections " 628 "at %"PRIx64, 629 __func__, mrs_gpa); 630 return; 631 } 632 } 633 } 634 } 635 636 if (need_add) { 637 ++dev->n_tmp_sections; 638 dev->tmp_sections = g_renew(MemoryRegionSection, dev->tmp_sections, 639 dev->n_tmp_sections); 640 dev->tmp_sections[dev->n_tmp_sections - 1] = *section; 641 /* The flatview isn't stable and we don't use it, making it NULL 642 * means we can memcmp the list. 643 */ 644 dev->tmp_sections[dev->n_tmp_sections - 1].fv = NULL; 645 memory_region_ref(section->mr); 646 } 647 } 648 649 /* Used for both add and nop callbacks */ 650 static void vhost_region_addnop(MemoryListener *listener, 651 MemoryRegionSection *section) 652 { 653 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 654 memory_listener); 655 656 if (!vhost_section(dev, section)) { 657 return; 658 } 659 vhost_region_add_section(dev, section); 660 } 661 662 static void vhost_iommu_unmap_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb) 663 { 664 struct vhost_iommu *iommu = container_of(n, struct vhost_iommu, n); 665 struct vhost_dev *hdev = iommu->hdev; 666 hwaddr iova = iotlb->iova + iommu->iommu_offset; 667 668 if (vhost_backend_invalidate_device_iotlb(hdev, iova, 669 iotlb->addr_mask + 1)) { 670 error_report("Fail to invalidate device iotlb"); 671 } 672 } 673 674 static void vhost_iommu_region_add(MemoryListener *listener, 675 MemoryRegionSection *section) 676 { 677 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 678 iommu_listener); 679 struct vhost_iommu *iommu; 680 Int128 end; 681 int iommu_idx, ret; 682 IOMMUMemoryRegion *iommu_mr; 683 Error *err = NULL; 684 685 if (!memory_region_is_iommu(section->mr)) { 686 return; 687 } 688 689 iommu_mr = IOMMU_MEMORY_REGION(section->mr); 690 691 iommu = g_malloc0(sizeof(*iommu)); 692 end = int128_add(int128_make64(section->offset_within_region), 693 section->size); 694 end = int128_sub(end, int128_one()); 695 iommu_idx = memory_region_iommu_attrs_to_index(iommu_mr, 696 MEMTXATTRS_UNSPECIFIED); 697 iommu_notifier_init(&iommu->n, vhost_iommu_unmap_notify, 698 IOMMU_NOTIFIER_UNMAP, 699 section->offset_within_region, 700 int128_get64(end), 701 iommu_idx); 702 iommu->mr = section->mr; 703 iommu->iommu_offset = section->offset_within_address_space - 704 section->offset_within_region; 705 iommu->hdev = dev; 706 ret = memory_region_register_iommu_notifier(section->mr, &iommu->n, &err); 707 if (ret) { 708 error_report_err(err); 709 exit(1); 710 } 711 QLIST_INSERT_HEAD(&dev->iommu_list, iommu, iommu_next); 712 /* TODO: can replay help performance here? */ 713 } 714 715 static void vhost_iommu_region_del(MemoryListener *listener, 716 MemoryRegionSection *section) 717 { 718 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 719 iommu_listener); 720 struct vhost_iommu *iommu; 721 722 if (!memory_region_is_iommu(section->mr)) { 723 return; 724 } 725 726 QLIST_FOREACH(iommu, &dev->iommu_list, iommu_next) { 727 if (iommu->mr == section->mr && 728 iommu->n.start == section->offset_within_region) { 729 memory_region_unregister_iommu_notifier(iommu->mr, 730 &iommu->n); 731 QLIST_REMOVE(iommu, iommu_next); 732 g_free(iommu); 733 break; 734 } 735 } 736 } 737 738 static int vhost_virtqueue_set_addr(struct vhost_dev *dev, 739 struct vhost_virtqueue *vq, 740 unsigned idx, bool enable_log) 741 { 742 struct vhost_vring_addr addr = { 743 .index = idx, 744 .desc_user_addr = (uint64_t)(unsigned long)vq->desc, 745 .avail_user_addr = (uint64_t)(unsigned long)vq->avail, 746 .used_user_addr = (uint64_t)(unsigned long)vq->used, 747 .log_guest_addr = vq->used_phys, 748 .flags = enable_log ? (1 << VHOST_VRING_F_LOG) : 0, 749 }; 750 int r = dev->vhost_ops->vhost_set_vring_addr(dev, &addr); 751 if (r < 0) { 752 VHOST_OPS_DEBUG("vhost_set_vring_addr failed"); 753 return -errno; 754 } 755 return 0; 756 } 757 758 static int vhost_dev_set_features(struct vhost_dev *dev, 759 bool enable_log) 760 { 761 uint64_t features = dev->acked_features; 762 int r; 763 if (enable_log) { 764 features |= 0x1ULL << VHOST_F_LOG_ALL; 765 } 766 r = dev->vhost_ops->vhost_set_features(dev, features); 767 if (r < 0) { 768 VHOST_OPS_DEBUG("vhost_set_features failed"); 769 } 770 return r < 0 ? -errno : 0; 771 } 772 773 static int vhost_dev_set_log(struct vhost_dev *dev, bool enable_log) 774 { 775 int r, i, idx; 776 r = vhost_dev_set_features(dev, enable_log); 777 if (r < 0) { 778 goto err_features; 779 } 780 for (i = 0; i < dev->nvqs; ++i) { 781 idx = dev->vhost_ops->vhost_get_vq_index(dev, dev->vq_index + i); 782 r = vhost_virtqueue_set_addr(dev, dev->vqs + i, idx, 783 enable_log); 784 if (r < 0) { 785 goto err_vq; 786 } 787 } 788 return 0; 789 err_vq: 790 for (; i >= 0; --i) { 791 idx = dev->vhost_ops->vhost_get_vq_index(dev, dev->vq_index + i); 792 vhost_virtqueue_set_addr(dev, dev->vqs + i, idx, 793 dev->log_enabled); 794 } 795 vhost_dev_set_features(dev, dev->log_enabled); 796 err_features: 797 return r; 798 } 799 800 static int vhost_migration_log(MemoryListener *listener, int enable) 801 { 802 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 803 memory_listener); 804 int r; 805 if (!!enable == dev->log_enabled) { 806 return 0; 807 } 808 if (!dev->started) { 809 dev->log_enabled = enable; 810 return 0; 811 } 812 if (!enable) { 813 r = vhost_dev_set_log(dev, false); 814 if (r < 0) { 815 return r; 816 } 817 vhost_log_put(dev, false); 818 } else { 819 vhost_dev_log_resize(dev, vhost_get_log_size(dev)); 820 r = vhost_dev_set_log(dev, true); 821 if (r < 0) { 822 return r; 823 } 824 } 825 dev->log_enabled = enable; 826 return 0; 827 } 828 829 static void vhost_log_global_start(MemoryListener *listener) 830 { 831 int r; 832 833 r = vhost_migration_log(listener, true); 834 if (r < 0) { 835 abort(); 836 } 837 } 838 839 static void vhost_log_global_stop(MemoryListener *listener) 840 { 841 int r; 842 843 r = vhost_migration_log(listener, false); 844 if (r < 0) { 845 abort(); 846 } 847 } 848 849 static void vhost_log_start(MemoryListener *listener, 850 MemoryRegionSection *section, 851 int old, int new) 852 { 853 /* FIXME: implement */ 854 } 855 856 static void vhost_log_stop(MemoryListener *listener, 857 MemoryRegionSection *section, 858 int old, int new) 859 { 860 /* FIXME: implement */ 861 } 862 863 /* The vhost driver natively knows how to handle the vrings of non 864 * cross-endian legacy devices and modern devices. Only legacy devices 865 * exposed to a bi-endian guest may require the vhost driver to use a 866 * specific endianness. 867 */ 868 static inline bool vhost_needs_vring_endian(VirtIODevice *vdev) 869 { 870 if (virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) { 871 return false; 872 } 873 #ifdef HOST_WORDS_BIGENDIAN 874 return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_LITTLE; 875 #else 876 return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG; 877 #endif 878 } 879 880 static int vhost_virtqueue_set_vring_endian_legacy(struct vhost_dev *dev, 881 bool is_big_endian, 882 int vhost_vq_index) 883 { 884 struct vhost_vring_state s = { 885 .index = vhost_vq_index, 886 .num = is_big_endian 887 }; 888 889 if (!dev->vhost_ops->vhost_set_vring_endian(dev, &s)) { 890 return 0; 891 } 892 893 VHOST_OPS_DEBUG("vhost_set_vring_endian failed"); 894 if (errno == ENOTTY) { 895 error_report("vhost does not support cross-endian"); 896 return -ENOSYS; 897 } 898 899 return -errno; 900 } 901 902 static int vhost_memory_region_lookup(struct vhost_dev *hdev, 903 uint64_t gpa, uint64_t *uaddr, 904 uint64_t *len) 905 { 906 int i; 907 908 for (i = 0; i < hdev->mem->nregions; i++) { 909 struct vhost_memory_region *reg = hdev->mem->regions + i; 910 911 if (gpa >= reg->guest_phys_addr && 912 reg->guest_phys_addr + reg->memory_size > gpa) { 913 *uaddr = reg->userspace_addr + gpa - reg->guest_phys_addr; 914 *len = reg->guest_phys_addr + reg->memory_size - gpa; 915 return 0; 916 } 917 } 918 919 return -EFAULT; 920 } 921 922 int vhost_device_iotlb_miss(struct vhost_dev *dev, uint64_t iova, int write) 923 { 924 IOMMUTLBEntry iotlb; 925 uint64_t uaddr, len; 926 int ret = -EFAULT; 927 928 RCU_READ_LOCK_GUARD(); 929 930 trace_vhost_iotlb_miss(dev, 1); 931 932 iotlb = address_space_get_iotlb_entry(dev->vdev->dma_as, 933 iova, write, 934 MEMTXATTRS_UNSPECIFIED); 935 if (iotlb.target_as != NULL) { 936 ret = vhost_memory_region_lookup(dev, iotlb.translated_addr, 937 &uaddr, &len); 938 if (ret) { 939 trace_vhost_iotlb_miss(dev, 3); 940 error_report("Fail to lookup the translated address " 941 "%"PRIx64, iotlb.translated_addr); 942 goto out; 943 } 944 945 len = MIN(iotlb.addr_mask + 1, len); 946 iova = iova & ~iotlb.addr_mask; 947 948 ret = vhost_backend_update_device_iotlb(dev, iova, uaddr, 949 len, iotlb.perm); 950 if (ret) { 951 trace_vhost_iotlb_miss(dev, 4); 952 error_report("Fail to update device iotlb"); 953 goto out; 954 } 955 } 956 957 trace_vhost_iotlb_miss(dev, 2); 958 959 out: 960 return ret; 961 } 962 963 static int vhost_virtqueue_start(struct vhost_dev *dev, 964 struct VirtIODevice *vdev, 965 struct vhost_virtqueue *vq, 966 unsigned idx) 967 { 968 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); 969 VirtioBusState *vbus = VIRTIO_BUS(qbus); 970 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(vbus); 971 hwaddr s, l, a; 972 int r; 973 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, idx); 974 struct vhost_vring_file file = { 975 .index = vhost_vq_index 976 }; 977 struct vhost_vring_state state = { 978 .index = vhost_vq_index 979 }; 980 struct VirtQueue *vvq = virtio_get_queue(vdev, idx); 981 982 a = virtio_queue_get_desc_addr(vdev, idx); 983 if (a == 0) { 984 /* Queue might not be ready for start */ 985 return 0; 986 } 987 988 vq->num = state.num = virtio_queue_get_num(vdev, idx); 989 r = dev->vhost_ops->vhost_set_vring_num(dev, &state); 990 if (r) { 991 VHOST_OPS_DEBUG("vhost_set_vring_num failed"); 992 return -errno; 993 } 994 995 state.num = virtio_queue_get_last_avail_idx(vdev, idx); 996 r = dev->vhost_ops->vhost_set_vring_base(dev, &state); 997 if (r) { 998 VHOST_OPS_DEBUG("vhost_set_vring_base failed"); 999 return -errno; 1000 } 1001 1002 if (vhost_needs_vring_endian(vdev)) { 1003 r = vhost_virtqueue_set_vring_endian_legacy(dev, 1004 virtio_is_big_endian(vdev), 1005 vhost_vq_index); 1006 if (r) { 1007 return -errno; 1008 } 1009 } 1010 1011 vq->desc_size = s = l = virtio_queue_get_desc_size(vdev, idx); 1012 vq->desc_phys = a; 1013 vq->desc = vhost_memory_map(dev, a, &l, 0); 1014 if (!vq->desc || l != s) { 1015 r = -ENOMEM; 1016 goto fail_alloc_desc; 1017 } 1018 vq->avail_size = s = l = virtio_queue_get_avail_size(vdev, idx); 1019 vq->avail_phys = a = virtio_queue_get_avail_addr(vdev, idx); 1020 vq->avail = vhost_memory_map(dev, a, &l, 0); 1021 if (!vq->avail || l != s) { 1022 r = -ENOMEM; 1023 goto fail_alloc_avail; 1024 } 1025 vq->used_size = s = l = virtio_queue_get_used_size(vdev, idx); 1026 vq->used_phys = a = virtio_queue_get_used_addr(vdev, idx); 1027 vq->used = vhost_memory_map(dev, a, &l, 1); 1028 if (!vq->used || l != s) { 1029 r = -ENOMEM; 1030 goto fail_alloc_used; 1031 } 1032 1033 r = vhost_virtqueue_set_addr(dev, vq, vhost_vq_index, dev->log_enabled); 1034 if (r < 0) { 1035 r = -errno; 1036 goto fail_alloc; 1037 } 1038 1039 file.fd = event_notifier_get_fd(virtio_queue_get_host_notifier(vvq)); 1040 r = dev->vhost_ops->vhost_set_vring_kick(dev, &file); 1041 if (r) { 1042 VHOST_OPS_DEBUG("vhost_set_vring_kick failed"); 1043 r = -errno; 1044 goto fail_kick; 1045 } 1046 1047 /* Clear and discard previous events if any. */ 1048 event_notifier_test_and_clear(&vq->masked_notifier); 1049 1050 /* Init vring in unmasked state, unless guest_notifier_mask 1051 * will do it later. 1052 */ 1053 if (!vdev->use_guest_notifier_mask) { 1054 /* TODO: check and handle errors. */ 1055 vhost_virtqueue_mask(dev, vdev, idx, false); 1056 } 1057 1058 if (k->query_guest_notifiers && 1059 k->query_guest_notifiers(qbus->parent) && 1060 virtio_queue_vector(vdev, idx) == VIRTIO_NO_VECTOR) { 1061 file.fd = -1; 1062 r = dev->vhost_ops->vhost_set_vring_call(dev, &file); 1063 if (r) { 1064 goto fail_vector; 1065 } 1066 } 1067 1068 return 0; 1069 1070 fail_vector: 1071 fail_kick: 1072 fail_alloc: 1073 vhost_memory_unmap(dev, vq->used, virtio_queue_get_used_size(vdev, idx), 1074 0, 0); 1075 fail_alloc_used: 1076 vhost_memory_unmap(dev, vq->avail, virtio_queue_get_avail_size(vdev, idx), 1077 0, 0); 1078 fail_alloc_avail: 1079 vhost_memory_unmap(dev, vq->desc, virtio_queue_get_desc_size(vdev, idx), 1080 0, 0); 1081 fail_alloc_desc: 1082 return r; 1083 } 1084 1085 static void vhost_virtqueue_stop(struct vhost_dev *dev, 1086 struct VirtIODevice *vdev, 1087 struct vhost_virtqueue *vq, 1088 unsigned idx) 1089 { 1090 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, idx); 1091 struct vhost_vring_state state = { 1092 .index = vhost_vq_index, 1093 }; 1094 int r; 1095 1096 if (virtio_queue_get_desc_addr(vdev, idx) == 0) { 1097 /* Don't stop the virtqueue which might have not been started */ 1098 return; 1099 } 1100 1101 r = dev->vhost_ops->vhost_get_vring_base(dev, &state); 1102 if (r < 0) { 1103 VHOST_OPS_DEBUG("vhost VQ %u ring restore failed: %d", idx, r); 1104 /* Connection to the backend is broken, so let's sync internal 1105 * last avail idx to the device used idx. 1106 */ 1107 virtio_queue_restore_last_avail_idx(vdev, idx); 1108 } else { 1109 virtio_queue_set_last_avail_idx(vdev, idx, state.num); 1110 } 1111 virtio_queue_invalidate_signalled_used(vdev, idx); 1112 virtio_queue_update_used_idx(vdev, idx); 1113 1114 /* In the cross-endian case, we need to reset the vring endianness to 1115 * native as legacy devices expect so by default. 1116 */ 1117 if (vhost_needs_vring_endian(vdev)) { 1118 vhost_virtqueue_set_vring_endian_legacy(dev, 1119 !virtio_is_big_endian(vdev), 1120 vhost_vq_index); 1121 } 1122 1123 vhost_memory_unmap(dev, vq->used, virtio_queue_get_used_size(vdev, idx), 1124 1, virtio_queue_get_used_size(vdev, idx)); 1125 vhost_memory_unmap(dev, vq->avail, virtio_queue_get_avail_size(vdev, idx), 1126 0, virtio_queue_get_avail_size(vdev, idx)); 1127 vhost_memory_unmap(dev, vq->desc, virtio_queue_get_desc_size(vdev, idx), 1128 0, virtio_queue_get_desc_size(vdev, idx)); 1129 } 1130 1131 static void vhost_eventfd_add(MemoryListener *listener, 1132 MemoryRegionSection *section, 1133 bool match_data, uint64_t data, EventNotifier *e) 1134 { 1135 } 1136 1137 static void vhost_eventfd_del(MemoryListener *listener, 1138 MemoryRegionSection *section, 1139 bool match_data, uint64_t data, EventNotifier *e) 1140 { 1141 } 1142 1143 static int vhost_virtqueue_set_busyloop_timeout(struct vhost_dev *dev, 1144 int n, uint32_t timeout) 1145 { 1146 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, n); 1147 struct vhost_vring_state state = { 1148 .index = vhost_vq_index, 1149 .num = timeout, 1150 }; 1151 int r; 1152 1153 if (!dev->vhost_ops->vhost_set_vring_busyloop_timeout) { 1154 return -EINVAL; 1155 } 1156 1157 r = dev->vhost_ops->vhost_set_vring_busyloop_timeout(dev, &state); 1158 if (r) { 1159 VHOST_OPS_DEBUG("vhost_set_vring_busyloop_timeout failed"); 1160 return r; 1161 } 1162 1163 return 0; 1164 } 1165 1166 static int vhost_virtqueue_init(struct vhost_dev *dev, 1167 struct vhost_virtqueue *vq, int n) 1168 { 1169 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, n); 1170 struct vhost_vring_file file = { 1171 .index = vhost_vq_index, 1172 }; 1173 int r = event_notifier_init(&vq->masked_notifier, 0); 1174 if (r < 0) { 1175 return r; 1176 } 1177 1178 file.fd = event_notifier_get_fd(&vq->masked_notifier); 1179 r = dev->vhost_ops->vhost_set_vring_call(dev, &file); 1180 if (r) { 1181 VHOST_OPS_DEBUG("vhost_set_vring_call failed"); 1182 r = -errno; 1183 goto fail_call; 1184 } 1185 1186 vq->dev = dev; 1187 1188 return 0; 1189 fail_call: 1190 event_notifier_cleanup(&vq->masked_notifier); 1191 return r; 1192 } 1193 1194 static void vhost_virtqueue_cleanup(struct vhost_virtqueue *vq) 1195 { 1196 event_notifier_cleanup(&vq->masked_notifier); 1197 } 1198 1199 int vhost_dev_init(struct vhost_dev *hdev, void *opaque, 1200 VhostBackendType backend_type, uint32_t busyloop_timeout) 1201 { 1202 uint64_t features; 1203 int i, r, n_initialized_vqs = 0; 1204 Error *local_err = NULL; 1205 1206 hdev->vdev = NULL; 1207 hdev->migration_blocker = NULL; 1208 1209 r = vhost_set_backend_type(hdev, backend_type); 1210 assert(r >= 0); 1211 1212 r = hdev->vhost_ops->vhost_backend_init(hdev, opaque); 1213 if (r < 0) { 1214 goto fail; 1215 } 1216 1217 r = hdev->vhost_ops->vhost_set_owner(hdev); 1218 if (r < 0) { 1219 VHOST_OPS_DEBUG("vhost_set_owner failed"); 1220 goto fail; 1221 } 1222 1223 r = hdev->vhost_ops->vhost_get_features(hdev, &features); 1224 if (r < 0) { 1225 VHOST_OPS_DEBUG("vhost_get_features failed"); 1226 goto fail; 1227 } 1228 1229 for (i = 0; i < hdev->nvqs; ++i, ++n_initialized_vqs) { 1230 r = vhost_virtqueue_init(hdev, hdev->vqs + i, hdev->vq_index + i); 1231 if (r < 0) { 1232 goto fail; 1233 } 1234 } 1235 1236 if (busyloop_timeout) { 1237 for (i = 0; i < hdev->nvqs; ++i) { 1238 r = vhost_virtqueue_set_busyloop_timeout(hdev, hdev->vq_index + i, 1239 busyloop_timeout); 1240 if (r < 0) { 1241 goto fail_busyloop; 1242 } 1243 } 1244 } 1245 1246 hdev->features = features; 1247 1248 hdev->memory_listener = (MemoryListener) { 1249 .begin = vhost_begin, 1250 .commit = vhost_commit, 1251 .region_add = vhost_region_addnop, 1252 .region_nop = vhost_region_addnop, 1253 .log_start = vhost_log_start, 1254 .log_stop = vhost_log_stop, 1255 .log_sync = vhost_log_sync, 1256 .log_global_start = vhost_log_global_start, 1257 .log_global_stop = vhost_log_global_stop, 1258 .eventfd_add = vhost_eventfd_add, 1259 .eventfd_del = vhost_eventfd_del, 1260 .priority = 10 1261 }; 1262 1263 hdev->iommu_listener = (MemoryListener) { 1264 .region_add = vhost_iommu_region_add, 1265 .region_del = vhost_iommu_region_del, 1266 }; 1267 1268 if (hdev->migration_blocker == NULL) { 1269 if (!(hdev->features & (0x1ULL << VHOST_F_LOG_ALL))) { 1270 error_setg(&hdev->migration_blocker, 1271 "Migration disabled: vhost lacks VHOST_F_LOG_ALL feature."); 1272 } else if (vhost_dev_log_is_shared(hdev) && !qemu_memfd_alloc_check()) { 1273 error_setg(&hdev->migration_blocker, 1274 "Migration disabled: failed to allocate shared memory"); 1275 } 1276 } 1277 1278 if (hdev->migration_blocker != NULL) { 1279 r = migrate_add_blocker(hdev->migration_blocker, &local_err); 1280 if (local_err) { 1281 error_report_err(local_err); 1282 error_free(hdev->migration_blocker); 1283 goto fail_busyloop; 1284 } 1285 } 1286 1287 hdev->mem = g_malloc0(offsetof(struct vhost_memory, regions)); 1288 hdev->n_mem_sections = 0; 1289 hdev->mem_sections = NULL; 1290 hdev->log = NULL; 1291 hdev->log_size = 0; 1292 hdev->log_enabled = false; 1293 hdev->started = false; 1294 memory_listener_register(&hdev->memory_listener, &address_space_memory); 1295 QLIST_INSERT_HEAD(&vhost_devices, hdev, entry); 1296 1297 if (used_memslots > hdev->vhost_ops->vhost_backend_memslots_limit(hdev)) { 1298 error_report("vhost backend memory slots limit is less" 1299 " than current number of present memory slots"); 1300 r = -1; 1301 if (busyloop_timeout) { 1302 goto fail_busyloop; 1303 } else { 1304 goto fail; 1305 } 1306 } 1307 1308 return 0; 1309 1310 fail_busyloop: 1311 while (--i >= 0) { 1312 vhost_virtqueue_set_busyloop_timeout(hdev, hdev->vq_index + i, 0); 1313 } 1314 fail: 1315 hdev->nvqs = n_initialized_vqs; 1316 vhost_dev_cleanup(hdev); 1317 return r; 1318 } 1319 1320 void vhost_dev_cleanup(struct vhost_dev *hdev) 1321 { 1322 int i; 1323 1324 for (i = 0; i < hdev->nvqs; ++i) { 1325 vhost_virtqueue_cleanup(hdev->vqs + i); 1326 } 1327 if (hdev->mem) { 1328 /* those are only safe after successful init */ 1329 memory_listener_unregister(&hdev->memory_listener); 1330 QLIST_REMOVE(hdev, entry); 1331 } 1332 if (hdev->migration_blocker) { 1333 migrate_del_blocker(hdev->migration_blocker); 1334 error_free(hdev->migration_blocker); 1335 } 1336 g_free(hdev->mem); 1337 g_free(hdev->mem_sections); 1338 if (hdev->vhost_ops) { 1339 hdev->vhost_ops->vhost_backend_cleanup(hdev); 1340 } 1341 assert(!hdev->log); 1342 1343 memset(hdev, 0, sizeof(struct vhost_dev)); 1344 } 1345 1346 /* Stop processing guest IO notifications in qemu. 1347 * Start processing them in vhost in kernel. 1348 */ 1349 int vhost_dev_enable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev) 1350 { 1351 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); 1352 int i, r, e; 1353 1354 /* We will pass the notifiers to the kernel, make sure that QEMU 1355 * doesn't interfere. 1356 */ 1357 r = virtio_device_grab_ioeventfd(vdev); 1358 if (r < 0) { 1359 error_report("binding does not support host notifiers"); 1360 goto fail; 1361 } 1362 1363 for (i = 0; i < hdev->nvqs; ++i) { 1364 r = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i, 1365 true); 1366 if (r < 0) { 1367 error_report("vhost VQ %d notifier binding failed: %d", i, -r); 1368 goto fail_vq; 1369 } 1370 } 1371 1372 return 0; 1373 fail_vq: 1374 while (--i >= 0) { 1375 e = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i, 1376 false); 1377 if (e < 0) { 1378 error_report("vhost VQ %d notifier cleanup error: %d", i, -r); 1379 } 1380 assert (e >= 0); 1381 virtio_bus_cleanup_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i); 1382 } 1383 virtio_device_release_ioeventfd(vdev); 1384 fail: 1385 return r; 1386 } 1387 1388 /* Stop processing guest IO notifications in vhost. 1389 * Start processing them in qemu. 1390 * This might actually run the qemu handlers right away, 1391 * so virtio in qemu must be completely setup when this is called. 1392 */ 1393 void vhost_dev_disable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev) 1394 { 1395 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); 1396 int i, r; 1397 1398 for (i = 0; i < hdev->nvqs; ++i) { 1399 r = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i, 1400 false); 1401 if (r < 0) { 1402 error_report("vhost VQ %d notifier cleanup failed: %d", i, -r); 1403 } 1404 assert (r >= 0); 1405 virtio_bus_cleanup_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i); 1406 } 1407 virtio_device_release_ioeventfd(vdev); 1408 } 1409 1410 /* Test and clear event pending status. 1411 * Should be called after unmask to avoid losing events. 1412 */ 1413 bool vhost_virtqueue_pending(struct vhost_dev *hdev, int n) 1414 { 1415 struct vhost_virtqueue *vq = hdev->vqs + n - hdev->vq_index; 1416 assert(n >= hdev->vq_index && n < hdev->vq_index + hdev->nvqs); 1417 return event_notifier_test_and_clear(&vq->masked_notifier); 1418 } 1419 1420 /* Mask/unmask events from this vq. */ 1421 void vhost_virtqueue_mask(struct vhost_dev *hdev, VirtIODevice *vdev, int n, 1422 bool mask) 1423 { 1424 struct VirtQueue *vvq = virtio_get_queue(vdev, n); 1425 int r, index = n - hdev->vq_index; 1426 struct vhost_vring_file file; 1427 1428 /* should only be called after backend is connected */ 1429 assert(hdev->vhost_ops); 1430 1431 if (mask) { 1432 assert(vdev->use_guest_notifier_mask); 1433 file.fd = event_notifier_get_fd(&hdev->vqs[index].masked_notifier); 1434 } else { 1435 file.fd = event_notifier_get_fd(virtio_queue_get_guest_notifier(vvq)); 1436 } 1437 1438 file.index = hdev->vhost_ops->vhost_get_vq_index(hdev, n); 1439 r = hdev->vhost_ops->vhost_set_vring_call(hdev, &file); 1440 if (r < 0) { 1441 VHOST_OPS_DEBUG("vhost_set_vring_call failed"); 1442 } 1443 } 1444 1445 uint64_t vhost_get_features(struct vhost_dev *hdev, const int *feature_bits, 1446 uint64_t features) 1447 { 1448 const int *bit = feature_bits; 1449 while (*bit != VHOST_INVALID_FEATURE_BIT) { 1450 uint64_t bit_mask = (1ULL << *bit); 1451 if (!(hdev->features & bit_mask)) { 1452 features &= ~bit_mask; 1453 } 1454 bit++; 1455 } 1456 return features; 1457 } 1458 1459 void vhost_ack_features(struct vhost_dev *hdev, const int *feature_bits, 1460 uint64_t features) 1461 { 1462 const int *bit = feature_bits; 1463 while (*bit != VHOST_INVALID_FEATURE_BIT) { 1464 uint64_t bit_mask = (1ULL << *bit); 1465 if (features & bit_mask) { 1466 hdev->acked_features |= bit_mask; 1467 } 1468 bit++; 1469 } 1470 } 1471 1472 int vhost_dev_get_config(struct vhost_dev *hdev, uint8_t *config, 1473 uint32_t config_len) 1474 { 1475 assert(hdev->vhost_ops); 1476 1477 if (hdev->vhost_ops->vhost_get_config) { 1478 return hdev->vhost_ops->vhost_get_config(hdev, config, config_len); 1479 } 1480 1481 return -1; 1482 } 1483 1484 int vhost_dev_set_config(struct vhost_dev *hdev, const uint8_t *data, 1485 uint32_t offset, uint32_t size, uint32_t flags) 1486 { 1487 assert(hdev->vhost_ops); 1488 1489 if (hdev->vhost_ops->vhost_set_config) { 1490 return hdev->vhost_ops->vhost_set_config(hdev, data, offset, 1491 size, flags); 1492 } 1493 1494 return -1; 1495 } 1496 1497 void vhost_dev_set_config_notifier(struct vhost_dev *hdev, 1498 const VhostDevConfigOps *ops) 1499 { 1500 hdev->config_ops = ops; 1501 } 1502 1503 void vhost_dev_free_inflight(struct vhost_inflight *inflight) 1504 { 1505 if (inflight->addr) { 1506 qemu_memfd_free(inflight->addr, inflight->size, inflight->fd); 1507 inflight->addr = NULL; 1508 inflight->fd = -1; 1509 } 1510 } 1511 1512 static int vhost_dev_resize_inflight(struct vhost_inflight *inflight, 1513 uint64_t new_size) 1514 { 1515 Error *err = NULL; 1516 int fd = -1; 1517 void *addr = qemu_memfd_alloc("vhost-inflight", new_size, 1518 F_SEAL_GROW | F_SEAL_SHRINK | F_SEAL_SEAL, 1519 &fd, &err); 1520 1521 if (err) { 1522 error_report_err(err); 1523 return -1; 1524 } 1525 1526 vhost_dev_free_inflight(inflight); 1527 inflight->offset = 0; 1528 inflight->addr = addr; 1529 inflight->fd = fd; 1530 inflight->size = new_size; 1531 1532 return 0; 1533 } 1534 1535 void vhost_dev_save_inflight(struct vhost_inflight *inflight, QEMUFile *f) 1536 { 1537 if (inflight->addr) { 1538 qemu_put_be64(f, inflight->size); 1539 qemu_put_be16(f, inflight->queue_size); 1540 qemu_put_buffer(f, inflight->addr, inflight->size); 1541 } else { 1542 qemu_put_be64(f, 0); 1543 } 1544 } 1545 1546 int vhost_dev_load_inflight(struct vhost_inflight *inflight, QEMUFile *f) 1547 { 1548 uint64_t size; 1549 1550 size = qemu_get_be64(f); 1551 if (!size) { 1552 return 0; 1553 } 1554 1555 if (inflight->size != size) { 1556 if (vhost_dev_resize_inflight(inflight, size)) { 1557 return -1; 1558 } 1559 } 1560 inflight->queue_size = qemu_get_be16(f); 1561 1562 qemu_get_buffer(f, inflight->addr, size); 1563 1564 return 0; 1565 } 1566 1567 int vhost_dev_set_inflight(struct vhost_dev *dev, 1568 struct vhost_inflight *inflight) 1569 { 1570 int r; 1571 1572 if (dev->vhost_ops->vhost_set_inflight_fd && inflight->addr) { 1573 r = dev->vhost_ops->vhost_set_inflight_fd(dev, inflight); 1574 if (r) { 1575 VHOST_OPS_DEBUG("vhost_set_inflight_fd failed"); 1576 return -errno; 1577 } 1578 } 1579 1580 return 0; 1581 } 1582 1583 int vhost_dev_get_inflight(struct vhost_dev *dev, uint16_t queue_size, 1584 struct vhost_inflight *inflight) 1585 { 1586 int r; 1587 1588 if (dev->vhost_ops->vhost_get_inflight_fd) { 1589 r = dev->vhost_ops->vhost_get_inflight_fd(dev, queue_size, inflight); 1590 if (r) { 1591 VHOST_OPS_DEBUG("vhost_get_inflight_fd failed"); 1592 return -errno; 1593 } 1594 } 1595 1596 return 0; 1597 } 1598 1599 /* Host notifiers must be enabled at this point. */ 1600 int vhost_dev_start(struct vhost_dev *hdev, VirtIODevice *vdev) 1601 { 1602 int i, r; 1603 1604 /* should only be called after backend is connected */ 1605 assert(hdev->vhost_ops); 1606 1607 hdev->started = true; 1608 hdev->vdev = vdev; 1609 1610 r = vhost_dev_set_features(hdev, hdev->log_enabled); 1611 if (r < 0) { 1612 goto fail_features; 1613 } 1614 1615 if (vhost_dev_has_iommu(hdev)) { 1616 memory_listener_register(&hdev->iommu_listener, vdev->dma_as); 1617 } 1618 1619 r = hdev->vhost_ops->vhost_set_mem_table(hdev, hdev->mem); 1620 if (r < 0) { 1621 VHOST_OPS_DEBUG("vhost_set_mem_table failed"); 1622 r = -errno; 1623 goto fail_mem; 1624 } 1625 for (i = 0; i < hdev->nvqs; ++i) { 1626 r = vhost_virtqueue_start(hdev, 1627 vdev, 1628 hdev->vqs + i, 1629 hdev->vq_index + i); 1630 if (r < 0) { 1631 goto fail_vq; 1632 } 1633 } 1634 1635 if (hdev->log_enabled) { 1636 uint64_t log_base; 1637 1638 hdev->log_size = vhost_get_log_size(hdev); 1639 hdev->log = vhost_log_get(hdev->log_size, 1640 vhost_dev_log_is_shared(hdev)); 1641 log_base = (uintptr_t)hdev->log->log; 1642 r = hdev->vhost_ops->vhost_set_log_base(hdev, 1643 hdev->log_size ? log_base : 0, 1644 hdev->log); 1645 if (r < 0) { 1646 VHOST_OPS_DEBUG("vhost_set_log_base failed"); 1647 r = -errno; 1648 goto fail_log; 1649 } 1650 } 1651 1652 if (vhost_dev_has_iommu(hdev)) { 1653 hdev->vhost_ops->vhost_set_iotlb_callback(hdev, true); 1654 1655 /* Update used ring information for IOTLB to work correctly, 1656 * vhost-kernel code requires for this.*/ 1657 for (i = 0; i < hdev->nvqs; ++i) { 1658 struct vhost_virtqueue *vq = hdev->vqs + i; 1659 vhost_device_iotlb_miss(hdev, vq->used_phys, true); 1660 } 1661 } 1662 return 0; 1663 fail_log: 1664 vhost_log_put(hdev, false); 1665 fail_vq: 1666 while (--i >= 0) { 1667 vhost_virtqueue_stop(hdev, 1668 vdev, 1669 hdev->vqs + i, 1670 hdev->vq_index + i); 1671 } 1672 1673 fail_mem: 1674 fail_features: 1675 1676 hdev->started = false; 1677 return r; 1678 } 1679 1680 /* Host notifiers must be enabled at this point. */ 1681 void vhost_dev_stop(struct vhost_dev *hdev, VirtIODevice *vdev) 1682 { 1683 int i; 1684 1685 /* should only be called after backend is connected */ 1686 assert(hdev->vhost_ops); 1687 1688 for (i = 0; i < hdev->nvqs; ++i) { 1689 vhost_virtqueue_stop(hdev, 1690 vdev, 1691 hdev->vqs + i, 1692 hdev->vq_index + i); 1693 } 1694 1695 if (vhost_dev_has_iommu(hdev)) { 1696 hdev->vhost_ops->vhost_set_iotlb_callback(hdev, false); 1697 memory_listener_unregister(&hdev->iommu_listener); 1698 } 1699 vhost_log_put(hdev, true); 1700 hdev->started = false; 1701 hdev->vdev = NULL; 1702 } 1703 1704 int vhost_net_set_backend(struct vhost_dev *hdev, 1705 struct vhost_vring_file *file) 1706 { 1707 if (hdev->vhost_ops->vhost_net_set_backend) { 1708 return hdev->vhost_ops->vhost_net_set_backend(hdev, file); 1709 } 1710 1711 return -1; 1712 } 1713