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 "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 changed = n_old_sections && memcmp(dev->mem_sections, old_sections, 455 n_old_sections * sizeof(old_sections[0])) != 0; 456 } 457 458 trace_vhost_commit(dev->started, changed); 459 if (!changed) { 460 goto out; 461 } 462 463 /* Rebuild the regions list from the new sections list */ 464 regions_size = offsetof(struct vhost_memory, regions) + 465 dev->n_mem_sections * sizeof dev->mem->regions[0]; 466 dev->mem = g_realloc(dev->mem, regions_size); 467 dev->mem->nregions = dev->n_mem_sections; 468 used_memslots = dev->mem->nregions; 469 for (i = 0; i < dev->n_mem_sections; i++) { 470 struct vhost_memory_region *cur_vmr = dev->mem->regions + i; 471 struct MemoryRegionSection *mrs = dev->mem_sections + i; 472 473 cur_vmr->guest_phys_addr = mrs->offset_within_address_space; 474 cur_vmr->memory_size = int128_get64(mrs->size); 475 cur_vmr->userspace_addr = 476 (uintptr_t)memory_region_get_ram_ptr(mrs->mr) + 477 mrs->offset_within_region; 478 cur_vmr->flags_padding = 0; 479 } 480 481 if (!dev->started) { 482 goto out; 483 } 484 485 for (i = 0; i < dev->mem->nregions; i++) { 486 if (vhost_verify_ring_mappings(dev, 487 (void *)(uintptr_t)dev->mem->regions[i].userspace_addr, 488 dev->mem->regions[i].guest_phys_addr, 489 dev->mem->regions[i].memory_size)) { 490 error_report("Verify ring failure on region %d", i); 491 abort(); 492 } 493 } 494 495 if (!dev->log_enabled) { 496 r = dev->vhost_ops->vhost_set_mem_table(dev, dev->mem); 497 if (r < 0) { 498 VHOST_OPS_DEBUG("vhost_set_mem_table failed"); 499 } 500 goto out; 501 } 502 log_size = vhost_get_log_size(dev); 503 /* We allocate an extra 4K bytes to log, 504 * to reduce the * number of reallocations. */ 505 #define VHOST_LOG_BUFFER (0x1000 / sizeof *dev->log) 506 /* To log more, must increase log size before table update. */ 507 if (dev->log_size < log_size) { 508 vhost_dev_log_resize(dev, log_size + VHOST_LOG_BUFFER); 509 } 510 r = dev->vhost_ops->vhost_set_mem_table(dev, dev->mem); 511 if (r < 0) { 512 VHOST_OPS_DEBUG("vhost_set_mem_table failed"); 513 } 514 /* To log less, can only decrease log size after table update. */ 515 if (dev->log_size > log_size + VHOST_LOG_BUFFER) { 516 vhost_dev_log_resize(dev, log_size); 517 } 518 519 out: 520 /* Deref the old list of sections, this must happen _after_ the 521 * vhost_set_mem_table to ensure the client isn't still using the 522 * section we're about to unref. 523 */ 524 while (n_old_sections--) { 525 memory_region_unref(old_sections[n_old_sections].mr); 526 } 527 g_free(old_sections); 528 return; 529 } 530 531 /* Adds the section data to the tmp_section structure. 532 * It relies on the listener calling us in memory address order 533 * and for each region (via the _add and _nop methods) to 534 * join neighbours. 535 */ 536 static void vhost_region_add_section(struct vhost_dev *dev, 537 MemoryRegionSection *section) 538 { 539 bool need_add = true; 540 uint64_t mrs_size = int128_get64(section->size); 541 uint64_t mrs_gpa = section->offset_within_address_space; 542 uintptr_t mrs_host = (uintptr_t)memory_region_get_ram_ptr(section->mr) + 543 section->offset_within_region; 544 RAMBlock *mrs_rb = section->mr->ram_block; 545 size_t mrs_page = qemu_ram_pagesize(mrs_rb); 546 547 trace_vhost_region_add_section(section->mr->name, mrs_gpa, mrs_size, 548 mrs_host); 549 550 /* Round the section to it's page size */ 551 /* First align the start down to a page boundary */ 552 uint64_t alignage = mrs_host & (mrs_page - 1); 553 if (alignage) { 554 mrs_host -= alignage; 555 mrs_size += alignage; 556 mrs_gpa -= alignage; 557 } 558 /* Now align the size up to a page boundary */ 559 alignage = mrs_size & (mrs_page - 1); 560 if (alignage) { 561 mrs_size += mrs_page - alignage; 562 } 563 trace_vhost_region_add_section_aligned(section->mr->name, mrs_gpa, mrs_size, 564 mrs_host); 565 566 if (dev->n_tmp_sections) { 567 /* Since we already have at least one section, lets see if 568 * this extends it; since we're scanning in order, we only 569 * have to look at the last one, and the FlatView that calls 570 * us shouldn't have overlaps. 571 */ 572 MemoryRegionSection *prev_sec = dev->tmp_sections + 573 (dev->n_tmp_sections - 1); 574 uint64_t prev_gpa_start = prev_sec->offset_within_address_space; 575 uint64_t prev_size = int128_get64(prev_sec->size); 576 uint64_t prev_gpa_end = range_get_last(prev_gpa_start, prev_size); 577 uint64_t prev_host_start = 578 (uintptr_t)memory_region_get_ram_ptr(prev_sec->mr) + 579 prev_sec->offset_within_region; 580 uint64_t prev_host_end = range_get_last(prev_host_start, prev_size); 581 582 if (mrs_gpa <= (prev_gpa_end + 1)) { 583 /* OK, looks like overlapping/intersecting - it's possible that 584 * the rounding to page sizes has made them overlap, but they should 585 * match up in the same RAMBlock if they do. 586 */ 587 if (mrs_gpa < prev_gpa_start) { 588 error_report("%s:Section rounded to %"PRIx64 589 " prior to previous %"PRIx64, 590 __func__, mrs_gpa, prev_gpa_start); 591 /* A way to cleanly fail here would be better */ 592 return; 593 } 594 /* Offset from the start of the previous GPA to this GPA */ 595 size_t offset = mrs_gpa - prev_gpa_start; 596 597 if (prev_host_start + offset == mrs_host && 598 section->mr == prev_sec->mr && 599 (!dev->vhost_ops->vhost_backend_can_merge || 600 dev->vhost_ops->vhost_backend_can_merge(dev, 601 mrs_host, mrs_size, 602 prev_host_start, prev_size))) { 603 uint64_t max_end = MAX(prev_host_end, mrs_host + mrs_size); 604 need_add = false; 605 prev_sec->offset_within_address_space = 606 MIN(prev_gpa_start, mrs_gpa); 607 prev_sec->offset_within_region = 608 MIN(prev_host_start, mrs_host) - 609 (uintptr_t)memory_region_get_ram_ptr(prev_sec->mr); 610 prev_sec->size = int128_make64(max_end - MIN(prev_host_start, 611 mrs_host)); 612 trace_vhost_region_add_section_merge(section->mr->name, 613 int128_get64(prev_sec->size), 614 prev_sec->offset_within_address_space, 615 prev_sec->offset_within_region); 616 } else { 617 /* adjoining regions are fine, but overlapping ones with 618 * different blocks/offsets shouldn't happen 619 */ 620 if (mrs_gpa != prev_gpa_end + 1) { 621 error_report("%s: Overlapping but not coherent sections " 622 "at %"PRIx64, 623 __func__, mrs_gpa); 624 return; 625 } 626 } 627 } 628 } 629 630 if (need_add) { 631 ++dev->n_tmp_sections; 632 dev->tmp_sections = g_renew(MemoryRegionSection, dev->tmp_sections, 633 dev->n_tmp_sections); 634 dev->tmp_sections[dev->n_tmp_sections - 1] = *section; 635 /* The flatview isn't stable and we don't use it, making it NULL 636 * means we can memcmp the list. 637 */ 638 dev->tmp_sections[dev->n_tmp_sections - 1].fv = NULL; 639 memory_region_ref(section->mr); 640 } 641 } 642 643 /* Used for both add and nop callbacks */ 644 static void vhost_region_addnop(MemoryListener *listener, 645 MemoryRegionSection *section) 646 { 647 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 648 memory_listener); 649 650 if (!vhost_section(dev, section)) { 651 return; 652 } 653 vhost_region_add_section(dev, section); 654 } 655 656 static void vhost_iommu_unmap_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb) 657 { 658 struct vhost_iommu *iommu = container_of(n, struct vhost_iommu, n); 659 struct vhost_dev *hdev = iommu->hdev; 660 hwaddr iova = iotlb->iova + iommu->iommu_offset; 661 662 if (vhost_backend_invalidate_device_iotlb(hdev, iova, 663 iotlb->addr_mask + 1)) { 664 error_report("Fail to invalidate device iotlb"); 665 } 666 } 667 668 static void vhost_iommu_region_add(MemoryListener *listener, 669 MemoryRegionSection *section) 670 { 671 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 672 iommu_listener); 673 struct vhost_iommu *iommu; 674 Int128 end; 675 int iommu_idx; 676 IOMMUMemoryRegion *iommu_mr; 677 678 if (!memory_region_is_iommu(section->mr)) { 679 return; 680 } 681 682 iommu_mr = IOMMU_MEMORY_REGION(section->mr); 683 684 iommu = g_malloc0(sizeof(*iommu)); 685 end = int128_add(int128_make64(section->offset_within_region), 686 section->size); 687 end = int128_sub(end, int128_one()); 688 iommu_idx = memory_region_iommu_attrs_to_index(iommu_mr, 689 MEMTXATTRS_UNSPECIFIED); 690 iommu_notifier_init(&iommu->n, vhost_iommu_unmap_notify, 691 IOMMU_NOTIFIER_UNMAP, 692 section->offset_within_region, 693 int128_get64(end), 694 iommu_idx); 695 iommu->mr = section->mr; 696 iommu->iommu_offset = section->offset_within_address_space - 697 section->offset_within_region; 698 iommu->hdev = dev; 699 memory_region_register_iommu_notifier(section->mr, &iommu->n); 700 QLIST_INSERT_HEAD(&dev->iommu_list, iommu, iommu_next); 701 /* TODO: can replay help performance here? */ 702 } 703 704 static void vhost_iommu_region_del(MemoryListener *listener, 705 MemoryRegionSection *section) 706 { 707 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 708 iommu_listener); 709 struct vhost_iommu *iommu; 710 711 if (!memory_region_is_iommu(section->mr)) { 712 return; 713 } 714 715 QLIST_FOREACH(iommu, &dev->iommu_list, iommu_next) { 716 if (iommu->mr == section->mr && 717 iommu->n.start == section->offset_within_region) { 718 memory_region_unregister_iommu_notifier(iommu->mr, 719 &iommu->n); 720 QLIST_REMOVE(iommu, iommu_next); 721 g_free(iommu); 722 break; 723 } 724 } 725 } 726 727 static int vhost_virtqueue_set_addr(struct vhost_dev *dev, 728 struct vhost_virtqueue *vq, 729 unsigned idx, bool enable_log) 730 { 731 struct vhost_vring_addr addr = { 732 .index = idx, 733 .desc_user_addr = (uint64_t)(unsigned long)vq->desc, 734 .avail_user_addr = (uint64_t)(unsigned long)vq->avail, 735 .used_user_addr = (uint64_t)(unsigned long)vq->used, 736 .log_guest_addr = vq->used_phys, 737 .flags = enable_log ? (1 << VHOST_VRING_F_LOG) : 0, 738 }; 739 int r = dev->vhost_ops->vhost_set_vring_addr(dev, &addr); 740 if (r < 0) { 741 VHOST_OPS_DEBUG("vhost_set_vring_addr failed"); 742 return -errno; 743 } 744 return 0; 745 } 746 747 static int vhost_dev_set_features(struct vhost_dev *dev, 748 bool enable_log) 749 { 750 uint64_t features = dev->acked_features; 751 int r; 752 if (enable_log) { 753 features |= 0x1ULL << VHOST_F_LOG_ALL; 754 } 755 r = dev->vhost_ops->vhost_set_features(dev, features); 756 if (r < 0) { 757 VHOST_OPS_DEBUG("vhost_set_features failed"); 758 } 759 return r < 0 ? -errno : 0; 760 } 761 762 static int vhost_dev_set_log(struct vhost_dev *dev, bool enable_log) 763 { 764 int r, i, idx; 765 r = vhost_dev_set_features(dev, enable_log); 766 if (r < 0) { 767 goto err_features; 768 } 769 for (i = 0; i < dev->nvqs; ++i) { 770 idx = dev->vhost_ops->vhost_get_vq_index(dev, dev->vq_index + i); 771 r = vhost_virtqueue_set_addr(dev, dev->vqs + i, idx, 772 enable_log); 773 if (r < 0) { 774 goto err_vq; 775 } 776 } 777 return 0; 778 err_vq: 779 for (; i >= 0; --i) { 780 idx = dev->vhost_ops->vhost_get_vq_index(dev, dev->vq_index + i); 781 vhost_virtqueue_set_addr(dev, dev->vqs + i, idx, 782 dev->log_enabled); 783 } 784 vhost_dev_set_features(dev, dev->log_enabled); 785 err_features: 786 return r; 787 } 788 789 static int vhost_migration_log(MemoryListener *listener, int enable) 790 { 791 struct vhost_dev *dev = container_of(listener, struct vhost_dev, 792 memory_listener); 793 int r; 794 if (!!enable == dev->log_enabled) { 795 return 0; 796 } 797 if (!dev->started) { 798 dev->log_enabled = enable; 799 return 0; 800 } 801 if (!enable) { 802 r = vhost_dev_set_log(dev, false); 803 if (r < 0) { 804 return r; 805 } 806 vhost_log_put(dev, false); 807 } else { 808 vhost_dev_log_resize(dev, vhost_get_log_size(dev)); 809 r = vhost_dev_set_log(dev, true); 810 if (r < 0) { 811 return r; 812 } 813 } 814 dev->log_enabled = enable; 815 return 0; 816 } 817 818 static void vhost_log_global_start(MemoryListener *listener) 819 { 820 int r; 821 822 r = vhost_migration_log(listener, true); 823 if (r < 0) { 824 abort(); 825 } 826 } 827 828 static void vhost_log_global_stop(MemoryListener *listener) 829 { 830 int r; 831 832 r = vhost_migration_log(listener, false); 833 if (r < 0) { 834 abort(); 835 } 836 } 837 838 static void vhost_log_start(MemoryListener *listener, 839 MemoryRegionSection *section, 840 int old, int new) 841 { 842 /* FIXME: implement */ 843 } 844 845 static void vhost_log_stop(MemoryListener *listener, 846 MemoryRegionSection *section, 847 int old, int new) 848 { 849 /* FIXME: implement */ 850 } 851 852 /* The vhost driver natively knows how to handle the vrings of non 853 * cross-endian legacy devices and modern devices. Only legacy devices 854 * exposed to a bi-endian guest may require the vhost driver to use a 855 * specific endianness. 856 */ 857 static inline bool vhost_needs_vring_endian(VirtIODevice *vdev) 858 { 859 if (virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) { 860 return false; 861 } 862 #ifdef HOST_WORDS_BIGENDIAN 863 return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_LITTLE; 864 #else 865 return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG; 866 #endif 867 } 868 869 static int vhost_virtqueue_set_vring_endian_legacy(struct vhost_dev *dev, 870 bool is_big_endian, 871 int vhost_vq_index) 872 { 873 struct vhost_vring_state s = { 874 .index = vhost_vq_index, 875 .num = is_big_endian 876 }; 877 878 if (!dev->vhost_ops->vhost_set_vring_endian(dev, &s)) { 879 return 0; 880 } 881 882 VHOST_OPS_DEBUG("vhost_set_vring_endian failed"); 883 if (errno == ENOTTY) { 884 error_report("vhost does not support cross-endian"); 885 return -ENOSYS; 886 } 887 888 return -errno; 889 } 890 891 static int vhost_memory_region_lookup(struct vhost_dev *hdev, 892 uint64_t gpa, uint64_t *uaddr, 893 uint64_t *len) 894 { 895 int i; 896 897 for (i = 0; i < hdev->mem->nregions; i++) { 898 struct vhost_memory_region *reg = hdev->mem->regions + i; 899 900 if (gpa >= reg->guest_phys_addr && 901 reg->guest_phys_addr + reg->memory_size > gpa) { 902 *uaddr = reg->userspace_addr + gpa - reg->guest_phys_addr; 903 *len = reg->guest_phys_addr + reg->memory_size - gpa; 904 return 0; 905 } 906 } 907 908 return -EFAULT; 909 } 910 911 int vhost_device_iotlb_miss(struct vhost_dev *dev, uint64_t iova, int write) 912 { 913 IOMMUTLBEntry iotlb; 914 uint64_t uaddr, len; 915 int ret = -EFAULT; 916 917 rcu_read_lock(); 918 919 trace_vhost_iotlb_miss(dev, 1); 920 921 iotlb = address_space_get_iotlb_entry(dev->vdev->dma_as, 922 iova, write, 923 MEMTXATTRS_UNSPECIFIED); 924 if (iotlb.target_as != NULL) { 925 ret = vhost_memory_region_lookup(dev, iotlb.translated_addr, 926 &uaddr, &len); 927 if (ret) { 928 trace_vhost_iotlb_miss(dev, 3); 929 error_report("Fail to lookup the translated address " 930 "%"PRIx64, iotlb.translated_addr); 931 goto out; 932 } 933 934 len = MIN(iotlb.addr_mask + 1, len); 935 iova = iova & ~iotlb.addr_mask; 936 937 ret = vhost_backend_update_device_iotlb(dev, iova, uaddr, 938 len, iotlb.perm); 939 if (ret) { 940 trace_vhost_iotlb_miss(dev, 4); 941 error_report("Fail to update device iotlb"); 942 goto out; 943 } 944 } 945 946 trace_vhost_iotlb_miss(dev, 2); 947 948 out: 949 rcu_read_unlock(); 950 951 return ret; 952 } 953 954 static int vhost_virtqueue_start(struct vhost_dev *dev, 955 struct VirtIODevice *vdev, 956 struct vhost_virtqueue *vq, 957 unsigned idx) 958 { 959 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); 960 VirtioBusState *vbus = VIRTIO_BUS(qbus); 961 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(vbus); 962 hwaddr s, l, a; 963 int r; 964 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, idx); 965 struct vhost_vring_file file = { 966 .index = vhost_vq_index 967 }; 968 struct vhost_vring_state state = { 969 .index = vhost_vq_index 970 }; 971 struct VirtQueue *vvq = virtio_get_queue(vdev, idx); 972 973 a = virtio_queue_get_desc_addr(vdev, idx); 974 if (a == 0) { 975 /* Queue might not be ready for start */ 976 return 0; 977 } 978 979 vq->num = state.num = virtio_queue_get_num(vdev, idx); 980 r = dev->vhost_ops->vhost_set_vring_num(dev, &state); 981 if (r) { 982 VHOST_OPS_DEBUG("vhost_set_vring_num failed"); 983 return -errno; 984 } 985 986 state.num = virtio_queue_get_last_avail_idx(vdev, idx); 987 r = dev->vhost_ops->vhost_set_vring_base(dev, &state); 988 if (r) { 989 VHOST_OPS_DEBUG("vhost_set_vring_base failed"); 990 return -errno; 991 } 992 993 if (vhost_needs_vring_endian(vdev)) { 994 r = vhost_virtqueue_set_vring_endian_legacy(dev, 995 virtio_is_big_endian(vdev), 996 vhost_vq_index); 997 if (r) { 998 return -errno; 999 } 1000 } 1001 1002 vq->desc_size = s = l = virtio_queue_get_desc_size(vdev, idx); 1003 vq->desc_phys = a; 1004 vq->desc = vhost_memory_map(dev, a, &l, 0); 1005 if (!vq->desc || l != s) { 1006 r = -ENOMEM; 1007 goto fail_alloc_desc; 1008 } 1009 vq->avail_size = s = l = virtio_queue_get_avail_size(vdev, idx); 1010 vq->avail_phys = a = virtio_queue_get_avail_addr(vdev, idx); 1011 vq->avail = vhost_memory_map(dev, a, &l, 0); 1012 if (!vq->avail || l != s) { 1013 r = -ENOMEM; 1014 goto fail_alloc_avail; 1015 } 1016 vq->used_size = s = l = virtio_queue_get_used_size(vdev, idx); 1017 vq->used_phys = a = virtio_queue_get_used_addr(vdev, idx); 1018 vq->used = vhost_memory_map(dev, a, &l, 1); 1019 if (!vq->used || l != s) { 1020 r = -ENOMEM; 1021 goto fail_alloc_used; 1022 } 1023 1024 r = vhost_virtqueue_set_addr(dev, vq, vhost_vq_index, dev->log_enabled); 1025 if (r < 0) { 1026 r = -errno; 1027 goto fail_alloc; 1028 } 1029 1030 file.fd = event_notifier_get_fd(virtio_queue_get_host_notifier(vvq)); 1031 r = dev->vhost_ops->vhost_set_vring_kick(dev, &file); 1032 if (r) { 1033 VHOST_OPS_DEBUG("vhost_set_vring_kick failed"); 1034 r = -errno; 1035 goto fail_kick; 1036 } 1037 1038 /* Clear and discard previous events if any. */ 1039 event_notifier_test_and_clear(&vq->masked_notifier); 1040 1041 /* Init vring in unmasked state, unless guest_notifier_mask 1042 * will do it later. 1043 */ 1044 if (!vdev->use_guest_notifier_mask) { 1045 /* TODO: check and handle errors. */ 1046 vhost_virtqueue_mask(dev, vdev, idx, false); 1047 } 1048 1049 if (k->query_guest_notifiers && 1050 k->query_guest_notifiers(qbus->parent) && 1051 virtio_queue_vector(vdev, idx) == VIRTIO_NO_VECTOR) { 1052 file.fd = -1; 1053 r = dev->vhost_ops->vhost_set_vring_call(dev, &file); 1054 if (r) { 1055 goto fail_vector; 1056 } 1057 } 1058 1059 return 0; 1060 1061 fail_vector: 1062 fail_kick: 1063 fail_alloc: 1064 vhost_memory_unmap(dev, vq->used, virtio_queue_get_used_size(vdev, idx), 1065 0, 0); 1066 fail_alloc_used: 1067 vhost_memory_unmap(dev, vq->avail, virtio_queue_get_avail_size(vdev, idx), 1068 0, 0); 1069 fail_alloc_avail: 1070 vhost_memory_unmap(dev, vq->desc, virtio_queue_get_desc_size(vdev, idx), 1071 0, 0); 1072 fail_alloc_desc: 1073 return r; 1074 } 1075 1076 static void vhost_virtqueue_stop(struct vhost_dev *dev, 1077 struct VirtIODevice *vdev, 1078 struct vhost_virtqueue *vq, 1079 unsigned idx) 1080 { 1081 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, idx); 1082 struct vhost_vring_state state = { 1083 .index = vhost_vq_index, 1084 }; 1085 int r; 1086 1087 if (virtio_queue_get_desc_addr(vdev, idx) == 0) { 1088 /* Don't stop the virtqueue which might have not been started */ 1089 return; 1090 } 1091 1092 r = dev->vhost_ops->vhost_get_vring_base(dev, &state); 1093 if (r < 0) { 1094 VHOST_OPS_DEBUG("vhost VQ %u ring restore failed: %d", idx, r); 1095 /* Connection to the backend is broken, so let's sync internal 1096 * last avail idx to the device used idx. 1097 */ 1098 virtio_queue_restore_last_avail_idx(vdev, idx); 1099 } else { 1100 virtio_queue_set_last_avail_idx(vdev, idx, state.num); 1101 } 1102 virtio_queue_invalidate_signalled_used(vdev, idx); 1103 virtio_queue_update_used_idx(vdev, idx); 1104 1105 /* In the cross-endian case, we need to reset the vring endianness to 1106 * native as legacy devices expect so by default. 1107 */ 1108 if (vhost_needs_vring_endian(vdev)) { 1109 vhost_virtqueue_set_vring_endian_legacy(dev, 1110 !virtio_is_big_endian(vdev), 1111 vhost_vq_index); 1112 } 1113 1114 vhost_memory_unmap(dev, vq->used, virtio_queue_get_used_size(vdev, idx), 1115 1, virtio_queue_get_used_size(vdev, idx)); 1116 vhost_memory_unmap(dev, vq->avail, virtio_queue_get_avail_size(vdev, idx), 1117 0, virtio_queue_get_avail_size(vdev, idx)); 1118 vhost_memory_unmap(dev, vq->desc, virtio_queue_get_desc_size(vdev, idx), 1119 0, virtio_queue_get_desc_size(vdev, idx)); 1120 } 1121 1122 static void vhost_eventfd_add(MemoryListener *listener, 1123 MemoryRegionSection *section, 1124 bool match_data, uint64_t data, EventNotifier *e) 1125 { 1126 } 1127 1128 static void vhost_eventfd_del(MemoryListener *listener, 1129 MemoryRegionSection *section, 1130 bool match_data, uint64_t data, EventNotifier *e) 1131 { 1132 } 1133 1134 static int vhost_virtqueue_set_busyloop_timeout(struct vhost_dev *dev, 1135 int n, uint32_t timeout) 1136 { 1137 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, n); 1138 struct vhost_vring_state state = { 1139 .index = vhost_vq_index, 1140 .num = timeout, 1141 }; 1142 int r; 1143 1144 if (!dev->vhost_ops->vhost_set_vring_busyloop_timeout) { 1145 return -EINVAL; 1146 } 1147 1148 r = dev->vhost_ops->vhost_set_vring_busyloop_timeout(dev, &state); 1149 if (r) { 1150 VHOST_OPS_DEBUG("vhost_set_vring_busyloop_timeout failed"); 1151 return r; 1152 } 1153 1154 return 0; 1155 } 1156 1157 static int vhost_virtqueue_init(struct vhost_dev *dev, 1158 struct vhost_virtqueue *vq, int n) 1159 { 1160 int vhost_vq_index = dev->vhost_ops->vhost_get_vq_index(dev, n); 1161 struct vhost_vring_file file = { 1162 .index = vhost_vq_index, 1163 }; 1164 int r = event_notifier_init(&vq->masked_notifier, 0); 1165 if (r < 0) { 1166 return r; 1167 } 1168 1169 file.fd = event_notifier_get_fd(&vq->masked_notifier); 1170 r = dev->vhost_ops->vhost_set_vring_call(dev, &file); 1171 if (r) { 1172 VHOST_OPS_DEBUG("vhost_set_vring_call failed"); 1173 r = -errno; 1174 goto fail_call; 1175 } 1176 1177 vq->dev = dev; 1178 1179 return 0; 1180 fail_call: 1181 event_notifier_cleanup(&vq->masked_notifier); 1182 return r; 1183 } 1184 1185 static void vhost_virtqueue_cleanup(struct vhost_virtqueue *vq) 1186 { 1187 event_notifier_cleanup(&vq->masked_notifier); 1188 } 1189 1190 int vhost_dev_init(struct vhost_dev *hdev, void *opaque, 1191 VhostBackendType backend_type, uint32_t busyloop_timeout) 1192 { 1193 uint64_t features; 1194 int i, r, n_initialized_vqs = 0; 1195 Error *local_err = NULL; 1196 1197 hdev->vdev = NULL; 1198 hdev->migration_blocker = NULL; 1199 1200 r = vhost_set_backend_type(hdev, backend_type); 1201 assert(r >= 0); 1202 1203 r = hdev->vhost_ops->vhost_backend_init(hdev, opaque); 1204 if (r < 0) { 1205 goto fail; 1206 } 1207 1208 r = hdev->vhost_ops->vhost_set_owner(hdev); 1209 if (r < 0) { 1210 VHOST_OPS_DEBUG("vhost_set_owner failed"); 1211 goto fail; 1212 } 1213 1214 r = hdev->vhost_ops->vhost_get_features(hdev, &features); 1215 if (r < 0) { 1216 VHOST_OPS_DEBUG("vhost_get_features failed"); 1217 goto fail; 1218 } 1219 1220 for (i = 0; i < hdev->nvqs; ++i, ++n_initialized_vqs) { 1221 r = vhost_virtqueue_init(hdev, hdev->vqs + i, hdev->vq_index + i); 1222 if (r < 0) { 1223 goto fail; 1224 } 1225 } 1226 1227 if (busyloop_timeout) { 1228 for (i = 0; i < hdev->nvqs; ++i) { 1229 r = vhost_virtqueue_set_busyloop_timeout(hdev, hdev->vq_index + i, 1230 busyloop_timeout); 1231 if (r < 0) { 1232 goto fail_busyloop; 1233 } 1234 } 1235 } 1236 1237 hdev->features = features; 1238 1239 hdev->memory_listener = (MemoryListener) { 1240 .begin = vhost_begin, 1241 .commit = vhost_commit, 1242 .region_add = vhost_region_addnop, 1243 .region_nop = vhost_region_addnop, 1244 .log_start = vhost_log_start, 1245 .log_stop = vhost_log_stop, 1246 .log_sync = vhost_log_sync, 1247 .log_global_start = vhost_log_global_start, 1248 .log_global_stop = vhost_log_global_stop, 1249 .eventfd_add = vhost_eventfd_add, 1250 .eventfd_del = vhost_eventfd_del, 1251 .priority = 10 1252 }; 1253 1254 hdev->iommu_listener = (MemoryListener) { 1255 .region_add = vhost_iommu_region_add, 1256 .region_del = vhost_iommu_region_del, 1257 }; 1258 1259 if (hdev->migration_blocker == NULL) { 1260 if (!(hdev->features & (0x1ULL << VHOST_F_LOG_ALL))) { 1261 error_setg(&hdev->migration_blocker, 1262 "Migration disabled: vhost lacks VHOST_F_LOG_ALL feature."); 1263 } else if (vhost_dev_log_is_shared(hdev) && !qemu_memfd_alloc_check()) { 1264 error_setg(&hdev->migration_blocker, 1265 "Migration disabled: failed to allocate shared memory"); 1266 } 1267 } 1268 1269 if (hdev->migration_blocker != NULL) { 1270 r = migrate_add_blocker(hdev->migration_blocker, &local_err); 1271 if (local_err) { 1272 error_report_err(local_err); 1273 error_free(hdev->migration_blocker); 1274 goto fail_busyloop; 1275 } 1276 } 1277 1278 hdev->mem = g_malloc0(offsetof(struct vhost_memory, regions)); 1279 hdev->n_mem_sections = 0; 1280 hdev->mem_sections = NULL; 1281 hdev->log = NULL; 1282 hdev->log_size = 0; 1283 hdev->log_enabled = false; 1284 hdev->started = false; 1285 memory_listener_register(&hdev->memory_listener, &address_space_memory); 1286 QLIST_INSERT_HEAD(&vhost_devices, hdev, entry); 1287 1288 if (used_memslots > hdev->vhost_ops->vhost_backend_memslots_limit(hdev)) { 1289 error_report("vhost backend memory slots limit is less" 1290 " than current number of present memory slots"); 1291 r = -1; 1292 if (busyloop_timeout) { 1293 goto fail_busyloop; 1294 } else { 1295 goto fail; 1296 } 1297 } 1298 1299 return 0; 1300 1301 fail_busyloop: 1302 while (--i >= 0) { 1303 vhost_virtqueue_set_busyloop_timeout(hdev, hdev->vq_index + i, 0); 1304 } 1305 fail: 1306 hdev->nvqs = n_initialized_vqs; 1307 vhost_dev_cleanup(hdev); 1308 return r; 1309 } 1310 1311 void vhost_dev_cleanup(struct vhost_dev *hdev) 1312 { 1313 int i; 1314 1315 for (i = 0; i < hdev->nvqs; ++i) { 1316 vhost_virtqueue_cleanup(hdev->vqs + i); 1317 } 1318 if (hdev->mem) { 1319 /* those are only safe after successful init */ 1320 memory_listener_unregister(&hdev->memory_listener); 1321 QLIST_REMOVE(hdev, entry); 1322 } 1323 if (hdev->migration_blocker) { 1324 migrate_del_blocker(hdev->migration_blocker); 1325 error_free(hdev->migration_blocker); 1326 } 1327 g_free(hdev->mem); 1328 g_free(hdev->mem_sections); 1329 if (hdev->vhost_ops) { 1330 hdev->vhost_ops->vhost_backend_cleanup(hdev); 1331 } 1332 assert(!hdev->log); 1333 1334 memset(hdev, 0, sizeof(struct vhost_dev)); 1335 } 1336 1337 /* Stop processing guest IO notifications in qemu. 1338 * Start processing them in vhost in kernel. 1339 */ 1340 int vhost_dev_enable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev) 1341 { 1342 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); 1343 int i, r, e; 1344 1345 /* We will pass the notifiers to the kernel, make sure that QEMU 1346 * doesn't interfere. 1347 */ 1348 r = virtio_device_grab_ioeventfd(vdev); 1349 if (r < 0) { 1350 error_report("binding does not support host notifiers"); 1351 goto fail; 1352 } 1353 1354 for (i = 0; i < hdev->nvqs; ++i) { 1355 r = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i, 1356 true); 1357 if (r < 0) { 1358 error_report("vhost VQ %d notifier binding failed: %d", i, -r); 1359 goto fail_vq; 1360 } 1361 } 1362 1363 return 0; 1364 fail_vq: 1365 while (--i >= 0) { 1366 e = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i, 1367 false); 1368 if (e < 0) { 1369 error_report("vhost VQ %d notifier cleanup error: %d", i, -r); 1370 } 1371 assert (e >= 0); 1372 virtio_bus_cleanup_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i); 1373 } 1374 virtio_device_release_ioeventfd(vdev); 1375 fail: 1376 return r; 1377 } 1378 1379 /* Stop processing guest IO notifications in vhost. 1380 * Start processing them in qemu. 1381 * This might actually run the qemu handlers right away, 1382 * so virtio in qemu must be completely setup when this is called. 1383 */ 1384 void vhost_dev_disable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev) 1385 { 1386 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); 1387 int i, r; 1388 1389 for (i = 0; i < hdev->nvqs; ++i) { 1390 r = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i, 1391 false); 1392 if (r < 0) { 1393 error_report("vhost VQ %d notifier cleanup failed: %d", i, -r); 1394 } 1395 assert (r >= 0); 1396 virtio_bus_cleanup_host_notifier(VIRTIO_BUS(qbus), hdev->vq_index + i); 1397 } 1398 virtio_device_release_ioeventfd(vdev); 1399 } 1400 1401 /* Test and clear event pending status. 1402 * Should be called after unmask to avoid losing events. 1403 */ 1404 bool vhost_virtqueue_pending(struct vhost_dev *hdev, int n) 1405 { 1406 struct vhost_virtqueue *vq = hdev->vqs + n - hdev->vq_index; 1407 assert(n >= hdev->vq_index && n < hdev->vq_index + hdev->nvqs); 1408 return event_notifier_test_and_clear(&vq->masked_notifier); 1409 } 1410 1411 /* Mask/unmask events from this vq. */ 1412 void vhost_virtqueue_mask(struct vhost_dev *hdev, VirtIODevice *vdev, int n, 1413 bool mask) 1414 { 1415 struct VirtQueue *vvq = virtio_get_queue(vdev, n); 1416 int r, index = n - hdev->vq_index; 1417 struct vhost_vring_file file; 1418 1419 /* should only be called after backend is connected */ 1420 assert(hdev->vhost_ops); 1421 1422 if (mask) { 1423 assert(vdev->use_guest_notifier_mask); 1424 file.fd = event_notifier_get_fd(&hdev->vqs[index].masked_notifier); 1425 } else { 1426 file.fd = event_notifier_get_fd(virtio_queue_get_guest_notifier(vvq)); 1427 } 1428 1429 file.index = hdev->vhost_ops->vhost_get_vq_index(hdev, n); 1430 r = hdev->vhost_ops->vhost_set_vring_call(hdev, &file); 1431 if (r < 0) { 1432 VHOST_OPS_DEBUG("vhost_set_vring_call failed"); 1433 } 1434 } 1435 1436 uint64_t vhost_get_features(struct vhost_dev *hdev, const int *feature_bits, 1437 uint64_t features) 1438 { 1439 const int *bit = feature_bits; 1440 while (*bit != VHOST_INVALID_FEATURE_BIT) { 1441 uint64_t bit_mask = (1ULL << *bit); 1442 if (!(hdev->features & bit_mask)) { 1443 features &= ~bit_mask; 1444 } 1445 bit++; 1446 } 1447 return features; 1448 } 1449 1450 void vhost_ack_features(struct vhost_dev *hdev, const int *feature_bits, 1451 uint64_t features) 1452 { 1453 const int *bit = feature_bits; 1454 while (*bit != VHOST_INVALID_FEATURE_BIT) { 1455 uint64_t bit_mask = (1ULL << *bit); 1456 if (features & bit_mask) { 1457 hdev->acked_features |= bit_mask; 1458 } 1459 bit++; 1460 } 1461 } 1462 1463 int vhost_dev_get_config(struct vhost_dev *hdev, uint8_t *config, 1464 uint32_t config_len) 1465 { 1466 assert(hdev->vhost_ops); 1467 1468 if (hdev->vhost_ops->vhost_get_config) { 1469 return hdev->vhost_ops->vhost_get_config(hdev, config, config_len); 1470 } 1471 1472 return -1; 1473 } 1474 1475 int vhost_dev_set_config(struct vhost_dev *hdev, const uint8_t *data, 1476 uint32_t offset, uint32_t size, uint32_t flags) 1477 { 1478 assert(hdev->vhost_ops); 1479 1480 if (hdev->vhost_ops->vhost_set_config) { 1481 return hdev->vhost_ops->vhost_set_config(hdev, data, offset, 1482 size, flags); 1483 } 1484 1485 return -1; 1486 } 1487 1488 void vhost_dev_set_config_notifier(struct vhost_dev *hdev, 1489 const VhostDevConfigOps *ops) 1490 { 1491 hdev->config_ops = ops; 1492 } 1493 1494 void vhost_dev_free_inflight(struct vhost_inflight *inflight) 1495 { 1496 if (inflight->addr) { 1497 qemu_memfd_free(inflight->addr, inflight->size, inflight->fd); 1498 inflight->addr = NULL; 1499 inflight->fd = -1; 1500 } 1501 } 1502 1503 static int vhost_dev_resize_inflight(struct vhost_inflight *inflight, 1504 uint64_t new_size) 1505 { 1506 Error *err = NULL; 1507 int fd = -1; 1508 void *addr = qemu_memfd_alloc("vhost-inflight", new_size, 1509 F_SEAL_GROW | F_SEAL_SHRINK | F_SEAL_SEAL, 1510 &fd, &err); 1511 1512 if (err) { 1513 error_report_err(err); 1514 return -1; 1515 } 1516 1517 vhost_dev_free_inflight(inflight); 1518 inflight->offset = 0; 1519 inflight->addr = addr; 1520 inflight->fd = fd; 1521 inflight->size = new_size; 1522 1523 return 0; 1524 } 1525 1526 void vhost_dev_save_inflight(struct vhost_inflight *inflight, QEMUFile *f) 1527 { 1528 if (inflight->addr) { 1529 qemu_put_be64(f, inflight->size); 1530 qemu_put_be16(f, inflight->queue_size); 1531 qemu_put_buffer(f, inflight->addr, inflight->size); 1532 } else { 1533 qemu_put_be64(f, 0); 1534 } 1535 } 1536 1537 int vhost_dev_load_inflight(struct vhost_inflight *inflight, QEMUFile *f) 1538 { 1539 uint64_t size; 1540 1541 size = qemu_get_be64(f); 1542 if (!size) { 1543 return 0; 1544 } 1545 1546 if (inflight->size != size) { 1547 if (vhost_dev_resize_inflight(inflight, size)) { 1548 return -1; 1549 } 1550 } 1551 inflight->queue_size = qemu_get_be16(f); 1552 1553 qemu_get_buffer(f, inflight->addr, size); 1554 1555 return 0; 1556 } 1557 1558 int vhost_dev_set_inflight(struct vhost_dev *dev, 1559 struct vhost_inflight *inflight) 1560 { 1561 int r; 1562 1563 if (dev->vhost_ops->vhost_set_inflight_fd && inflight->addr) { 1564 r = dev->vhost_ops->vhost_set_inflight_fd(dev, inflight); 1565 if (r) { 1566 VHOST_OPS_DEBUG("vhost_set_inflight_fd failed"); 1567 return -errno; 1568 } 1569 } 1570 1571 return 0; 1572 } 1573 1574 int vhost_dev_get_inflight(struct vhost_dev *dev, uint16_t queue_size, 1575 struct vhost_inflight *inflight) 1576 { 1577 int r; 1578 1579 if (dev->vhost_ops->vhost_get_inflight_fd) { 1580 r = dev->vhost_ops->vhost_get_inflight_fd(dev, queue_size, inflight); 1581 if (r) { 1582 VHOST_OPS_DEBUG("vhost_get_inflight_fd failed"); 1583 return -errno; 1584 } 1585 } 1586 1587 return 0; 1588 } 1589 1590 /* Host notifiers must be enabled at this point. */ 1591 int vhost_dev_start(struct vhost_dev *hdev, VirtIODevice *vdev) 1592 { 1593 int i, r; 1594 1595 /* should only be called after backend is connected */ 1596 assert(hdev->vhost_ops); 1597 1598 hdev->started = true; 1599 hdev->vdev = vdev; 1600 1601 r = vhost_dev_set_features(hdev, hdev->log_enabled); 1602 if (r < 0) { 1603 goto fail_features; 1604 } 1605 1606 if (vhost_dev_has_iommu(hdev)) { 1607 memory_listener_register(&hdev->iommu_listener, vdev->dma_as); 1608 } 1609 1610 r = hdev->vhost_ops->vhost_set_mem_table(hdev, hdev->mem); 1611 if (r < 0) { 1612 VHOST_OPS_DEBUG("vhost_set_mem_table failed"); 1613 r = -errno; 1614 goto fail_mem; 1615 } 1616 for (i = 0; i < hdev->nvqs; ++i) { 1617 r = vhost_virtqueue_start(hdev, 1618 vdev, 1619 hdev->vqs + i, 1620 hdev->vq_index + i); 1621 if (r < 0) { 1622 goto fail_vq; 1623 } 1624 } 1625 1626 if (hdev->log_enabled) { 1627 uint64_t log_base; 1628 1629 hdev->log_size = vhost_get_log_size(hdev); 1630 hdev->log = vhost_log_get(hdev->log_size, 1631 vhost_dev_log_is_shared(hdev)); 1632 log_base = (uintptr_t)hdev->log->log; 1633 r = hdev->vhost_ops->vhost_set_log_base(hdev, 1634 hdev->log_size ? log_base : 0, 1635 hdev->log); 1636 if (r < 0) { 1637 VHOST_OPS_DEBUG("vhost_set_log_base failed"); 1638 r = -errno; 1639 goto fail_log; 1640 } 1641 } 1642 1643 if (vhost_dev_has_iommu(hdev)) { 1644 hdev->vhost_ops->vhost_set_iotlb_callback(hdev, true); 1645 1646 /* Update used ring information for IOTLB to work correctly, 1647 * vhost-kernel code requires for this.*/ 1648 for (i = 0; i < hdev->nvqs; ++i) { 1649 struct vhost_virtqueue *vq = hdev->vqs + i; 1650 vhost_device_iotlb_miss(hdev, vq->used_phys, true); 1651 } 1652 } 1653 return 0; 1654 fail_log: 1655 vhost_log_put(hdev, false); 1656 fail_vq: 1657 while (--i >= 0) { 1658 vhost_virtqueue_stop(hdev, 1659 vdev, 1660 hdev->vqs + i, 1661 hdev->vq_index + i); 1662 } 1663 1664 fail_mem: 1665 fail_features: 1666 1667 hdev->started = false; 1668 return r; 1669 } 1670 1671 /* Host notifiers must be enabled at this point. */ 1672 void vhost_dev_stop(struct vhost_dev *hdev, VirtIODevice *vdev) 1673 { 1674 int i; 1675 1676 /* should only be called after backend is connected */ 1677 assert(hdev->vhost_ops); 1678 1679 for (i = 0; i < hdev->nvqs; ++i) { 1680 vhost_virtqueue_stop(hdev, 1681 vdev, 1682 hdev->vqs + i, 1683 hdev->vq_index + i); 1684 } 1685 1686 if (vhost_dev_has_iommu(hdev)) { 1687 hdev->vhost_ops->vhost_set_iotlb_callback(hdev, false); 1688 memory_listener_unregister(&hdev->iommu_listener); 1689 } 1690 vhost_log_put(hdev, true); 1691 hdev->started = false; 1692 hdev->vdev = NULL; 1693 } 1694 1695 int vhost_net_set_backend(struct vhost_dev *hdev, 1696 struct vhost_vring_file *file) 1697 { 1698 if (hdev->vhost_ops->vhost_net_set_backend) { 1699 return hdev->vhost_ops->vhost_net_set_backend(hdev, file); 1700 } 1701 1702 return -1; 1703 } 1704