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