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