1 /* 2 * Migration support for VFIO devices 3 * 4 * Copyright NVIDIA, Inc. 2020 5 * 6 * This work is licensed under the terms of the GNU GPL, version 2. See 7 * the COPYING file in the top-level directory. 8 */ 9 10 #include "qemu/osdep.h" 11 #include "qemu/main-loop.h" 12 #include "qemu/cutils.h" 13 #include <linux/vfio.h> 14 #include <sys/ioctl.h> 15 16 #include "sysemu/runstate.h" 17 #include "hw/vfio/vfio-common.h" 18 #include "migration/migration.h" 19 #include "migration/vmstate.h" 20 #include "migration/qemu-file.h" 21 #include "migration/register.h" 22 #include "migration/blocker.h" 23 #include "migration/misc.h" 24 #include "qapi/error.h" 25 #include "exec/ramlist.h" 26 #include "exec/ram_addr.h" 27 #include "pci.h" 28 #include "trace.h" 29 #include "hw/hw.h" 30 31 /* 32 * Flags to be used as unique delimiters for VFIO devices in the migration 33 * stream. These flags are composed as: 34 * 0xffffffff => MSB 32-bit all 1s 35 * 0xef10 => Magic ID, represents emulated (virtual) function IO 36 * 0x0000 => 16-bits reserved for flags 37 * 38 * The beginning of state information is marked by _DEV_CONFIG_STATE, 39 * _DEV_SETUP_STATE, or _DEV_DATA_STATE, respectively. The end of a 40 * certain state information is marked by _END_OF_STATE. 41 */ 42 #define VFIO_MIG_FLAG_END_OF_STATE (0xffffffffef100001ULL) 43 #define VFIO_MIG_FLAG_DEV_CONFIG_STATE (0xffffffffef100002ULL) 44 #define VFIO_MIG_FLAG_DEV_SETUP_STATE (0xffffffffef100003ULL) 45 #define VFIO_MIG_FLAG_DEV_DATA_STATE (0xffffffffef100004ULL) 46 47 static int64_t bytes_transferred; 48 49 static inline int vfio_mig_access(VFIODevice *vbasedev, void *val, int count, 50 off_t off, bool iswrite) 51 { 52 int ret; 53 54 ret = iswrite ? pwrite(vbasedev->fd, val, count, off) : 55 pread(vbasedev->fd, val, count, off); 56 if (ret < count) { 57 error_report("vfio_mig_%s %d byte %s: failed at offset 0x%" 58 HWADDR_PRIx", err: %s", iswrite ? "write" : "read", count, 59 vbasedev->name, off, strerror(errno)); 60 return (ret < 0) ? ret : -EINVAL; 61 } 62 return 0; 63 } 64 65 static int vfio_mig_rw(VFIODevice *vbasedev, __u8 *buf, size_t count, 66 off_t off, bool iswrite) 67 { 68 int ret, done = 0; 69 __u8 *tbuf = buf; 70 71 while (count) { 72 int bytes = 0; 73 74 if (count >= 8 && !(off % 8)) { 75 bytes = 8; 76 } else if (count >= 4 && !(off % 4)) { 77 bytes = 4; 78 } else if (count >= 2 && !(off % 2)) { 79 bytes = 2; 80 } else { 81 bytes = 1; 82 } 83 84 ret = vfio_mig_access(vbasedev, tbuf, bytes, off, iswrite); 85 if (ret) { 86 return ret; 87 } 88 89 count -= bytes; 90 done += bytes; 91 off += bytes; 92 tbuf += bytes; 93 } 94 return done; 95 } 96 97 #define vfio_mig_read(f, v, c, o) vfio_mig_rw(f, (__u8 *)v, c, o, false) 98 #define vfio_mig_write(f, v, c, o) vfio_mig_rw(f, (__u8 *)v, c, o, true) 99 100 #define VFIO_MIG_STRUCT_OFFSET(f) \ 101 offsetof(struct vfio_device_migration_info, f) 102 /* 103 * Change the device_state register for device @vbasedev. Bits set in @mask 104 * are preserved, bits set in @value are set, and bits not set in either @mask 105 * or @value are cleared in device_state. If the register cannot be accessed, 106 * the resulting state would be invalid, or the device enters an error state, 107 * an error is returned. 108 */ 109 110 static int vfio_migration_set_state(VFIODevice *vbasedev, uint32_t mask, 111 uint32_t value) 112 { 113 VFIOMigration *migration = vbasedev->migration; 114 VFIORegion *region = &migration->region; 115 off_t dev_state_off = region->fd_offset + 116 VFIO_MIG_STRUCT_OFFSET(device_state); 117 uint32_t device_state; 118 int ret; 119 120 ret = vfio_mig_read(vbasedev, &device_state, sizeof(device_state), 121 dev_state_off); 122 if (ret < 0) { 123 return ret; 124 } 125 126 device_state = (device_state & mask) | value; 127 128 if (!VFIO_DEVICE_STATE_VALID(device_state)) { 129 return -EINVAL; 130 } 131 132 ret = vfio_mig_write(vbasedev, &device_state, sizeof(device_state), 133 dev_state_off); 134 if (ret < 0) { 135 int rret; 136 137 rret = vfio_mig_read(vbasedev, &device_state, sizeof(device_state), 138 dev_state_off); 139 140 if ((rret < 0) || (VFIO_DEVICE_STATE_IS_ERROR(device_state))) { 141 hw_error("%s: Device in error state 0x%x", vbasedev->name, 142 device_state); 143 return rret ? rret : -EIO; 144 } 145 return ret; 146 } 147 148 migration->device_state = device_state; 149 trace_vfio_migration_set_state(vbasedev->name, device_state); 150 return 0; 151 } 152 153 static void *get_data_section_size(VFIORegion *region, uint64_t data_offset, 154 uint64_t data_size, uint64_t *size) 155 { 156 void *ptr = NULL; 157 uint64_t limit = 0; 158 int i; 159 160 if (!region->mmaps) { 161 if (size) { 162 *size = MIN(data_size, region->size - data_offset); 163 } 164 return ptr; 165 } 166 167 for (i = 0; i < region->nr_mmaps; i++) { 168 VFIOMmap *map = region->mmaps + i; 169 170 if ((data_offset >= map->offset) && 171 (data_offset < map->offset + map->size)) { 172 173 /* check if data_offset is within sparse mmap areas */ 174 ptr = map->mmap + data_offset - map->offset; 175 if (size) { 176 *size = MIN(data_size, map->offset + map->size - data_offset); 177 } 178 break; 179 } else if ((data_offset < map->offset) && 180 (!limit || limit > map->offset)) { 181 /* 182 * data_offset is not within sparse mmap areas, find size of 183 * non-mapped area. Check through all list since region->mmaps list 184 * is not sorted. 185 */ 186 limit = map->offset; 187 } 188 } 189 190 if (!ptr && size) { 191 *size = limit ? MIN(data_size, limit - data_offset) : data_size; 192 } 193 return ptr; 194 } 195 196 static int vfio_save_buffer(QEMUFile *f, VFIODevice *vbasedev, uint64_t *size) 197 { 198 VFIOMigration *migration = vbasedev->migration; 199 VFIORegion *region = &migration->region; 200 uint64_t data_offset = 0, data_size = 0, sz; 201 int ret; 202 203 ret = vfio_mig_read(vbasedev, &data_offset, sizeof(data_offset), 204 region->fd_offset + VFIO_MIG_STRUCT_OFFSET(data_offset)); 205 if (ret < 0) { 206 return ret; 207 } 208 209 ret = vfio_mig_read(vbasedev, &data_size, sizeof(data_size), 210 region->fd_offset + VFIO_MIG_STRUCT_OFFSET(data_size)); 211 if (ret < 0) { 212 return ret; 213 } 214 215 trace_vfio_save_buffer(vbasedev->name, data_offset, data_size, 216 migration->pending_bytes); 217 218 qemu_put_be64(f, data_size); 219 sz = data_size; 220 221 while (sz) { 222 void *buf; 223 uint64_t sec_size; 224 bool buf_allocated = false; 225 226 buf = get_data_section_size(region, data_offset, sz, &sec_size); 227 228 if (!buf) { 229 buf = g_try_malloc(sec_size); 230 if (!buf) { 231 error_report("%s: Error allocating buffer ", __func__); 232 return -ENOMEM; 233 } 234 buf_allocated = true; 235 236 ret = vfio_mig_read(vbasedev, buf, sec_size, 237 region->fd_offset + data_offset); 238 if (ret < 0) { 239 g_free(buf); 240 return ret; 241 } 242 } 243 244 qemu_put_buffer(f, buf, sec_size); 245 246 if (buf_allocated) { 247 g_free(buf); 248 } 249 sz -= sec_size; 250 data_offset += sec_size; 251 } 252 253 ret = qemu_file_get_error(f); 254 255 if (!ret && size) { 256 *size = data_size; 257 } 258 259 bytes_transferred += data_size; 260 return ret; 261 } 262 263 static int vfio_load_buffer(QEMUFile *f, VFIODevice *vbasedev, 264 uint64_t data_size) 265 { 266 VFIORegion *region = &vbasedev->migration->region; 267 uint64_t data_offset = 0, size, report_size; 268 int ret; 269 270 do { 271 ret = vfio_mig_read(vbasedev, &data_offset, sizeof(data_offset), 272 region->fd_offset + VFIO_MIG_STRUCT_OFFSET(data_offset)); 273 if (ret < 0) { 274 return ret; 275 } 276 277 if (data_offset + data_size > region->size) { 278 /* 279 * If data_size is greater than the data section of migration region 280 * then iterate the write buffer operation. This case can occur if 281 * size of migration region at destination is smaller than size of 282 * migration region at source. 283 */ 284 report_size = size = region->size - data_offset; 285 data_size -= size; 286 } else { 287 report_size = size = data_size; 288 data_size = 0; 289 } 290 291 trace_vfio_load_state_device_data(vbasedev->name, data_offset, size); 292 293 while (size) { 294 void *buf; 295 uint64_t sec_size; 296 bool buf_alloc = false; 297 298 buf = get_data_section_size(region, data_offset, size, &sec_size); 299 300 if (!buf) { 301 buf = g_try_malloc(sec_size); 302 if (!buf) { 303 error_report("%s: Error allocating buffer ", __func__); 304 return -ENOMEM; 305 } 306 buf_alloc = true; 307 } 308 309 qemu_get_buffer(f, buf, sec_size); 310 311 if (buf_alloc) { 312 ret = vfio_mig_write(vbasedev, buf, sec_size, 313 region->fd_offset + data_offset); 314 g_free(buf); 315 316 if (ret < 0) { 317 return ret; 318 } 319 } 320 size -= sec_size; 321 data_offset += sec_size; 322 } 323 324 ret = vfio_mig_write(vbasedev, &report_size, sizeof(report_size), 325 region->fd_offset + VFIO_MIG_STRUCT_OFFSET(data_size)); 326 if (ret < 0) { 327 return ret; 328 } 329 } while (data_size); 330 331 return 0; 332 } 333 334 static int vfio_update_pending(VFIODevice *vbasedev) 335 { 336 VFIOMigration *migration = vbasedev->migration; 337 VFIORegion *region = &migration->region; 338 uint64_t pending_bytes = 0; 339 int ret; 340 341 ret = vfio_mig_read(vbasedev, &pending_bytes, sizeof(pending_bytes), 342 region->fd_offset + VFIO_MIG_STRUCT_OFFSET(pending_bytes)); 343 if (ret < 0) { 344 migration->pending_bytes = 0; 345 return ret; 346 } 347 348 migration->pending_bytes = pending_bytes; 349 trace_vfio_update_pending(vbasedev->name, pending_bytes); 350 return 0; 351 } 352 353 static int vfio_save_device_config_state(QEMUFile *f, void *opaque) 354 { 355 VFIODevice *vbasedev = opaque; 356 357 qemu_put_be64(f, VFIO_MIG_FLAG_DEV_CONFIG_STATE); 358 359 if (vbasedev->ops && vbasedev->ops->vfio_save_config) { 360 vbasedev->ops->vfio_save_config(vbasedev, f); 361 } 362 363 qemu_put_be64(f, VFIO_MIG_FLAG_END_OF_STATE); 364 365 trace_vfio_save_device_config_state(vbasedev->name); 366 367 return qemu_file_get_error(f); 368 } 369 370 static int vfio_load_device_config_state(QEMUFile *f, void *opaque) 371 { 372 VFIODevice *vbasedev = opaque; 373 uint64_t data; 374 375 if (vbasedev->ops && vbasedev->ops->vfio_load_config) { 376 int ret; 377 378 ret = vbasedev->ops->vfio_load_config(vbasedev, f); 379 if (ret) { 380 error_report("%s: Failed to load device config space", 381 vbasedev->name); 382 return ret; 383 } 384 } 385 386 data = qemu_get_be64(f); 387 if (data != VFIO_MIG_FLAG_END_OF_STATE) { 388 error_report("%s: Failed loading device config space, " 389 "end flag incorrect 0x%"PRIx64, vbasedev->name, data); 390 return -EINVAL; 391 } 392 393 trace_vfio_load_device_config_state(vbasedev->name); 394 return qemu_file_get_error(f); 395 } 396 397 static void vfio_migration_cleanup(VFIODevice *vbasedev) 398 { 399 VFIOMigration *migration = vbasedev->migration; 400 401 if (migration->region.mmaps) { 402 vfio_region_unmap(&migration->region); 403 } 404 } 405 406 /* ---------------------------------------------------------------------- */ 407 408 static int vfio_save_setup(QEMUFile *f, void *opaque) 409 { 410 VFIODevice *vbasedev = opaque; 411 VFIOMigration *migration = vbasedev->migration; 412 int ret; 413 414 trace_vfio_save_setup(vbasedev->name); 415 416 qemu_put_be64(f, VFIO_MIG_FLAG_DEV_SETUP_STATE); 417 418 if (migration->region.mmaps) { 419 /* 420 * Calling vfio_region_mmap() from migration thread. Memory API called 421 * from this function require locking the iothread when called from 422 * outside the main loop thread. 423 */ 424 qemu_mutex_lock_iothread(); 425 ret = vfio_region_mmap(&migration->region); 426 qemu_mutex_unlock_iothread(); 427 if (ret) { 428 error_report("%s: Failed to mmap VFIO migration region: %s", 429 vbasedev->name, strerror(-ret)); 430 error_report("%s: Falling back to slow path", vbasedev->name); 431 } 432 } 433 434 ret = vfio_migration_set_state(vbasedev, VFIO_DEVICE_STATE_MASK, 435 VFIO_DEVICE_STATE_SAVING); 436 if (ret) { 437 error_report("%s: Failed to set state SAVING", vbasedev->name); 438 return ret; 439 } 440 441 qemu_put_be64(f, VFIO_MIG_FLAG_END_OF_STATE); 442 443 ret = qemu_file_get_error(f); 444 if (ret) { 445 return ret; 446 } 447 448 return 0; 449 } 450 451 static void vfio_save_cleanup(void *opaque) 452 { 453 VFIODevice *vbasedev = opaque; 454 455 vfio_migration_cleanup(vbasedev); 456 trace_vfio_save_cleanup(vbasedev->name); 457 } 458 459 static void vfio_save_pending(QEMUFile *f, void *opaque, 460 uint64_t threshold_size, 461 uint64_t *res_precopy_only, 462 uint64_t *res_compatible, 463 uint64_t *res_postcopy_only) 464 { 465 VFIODevice *vbasedev = opaque; 466 VFIOMigration *migration = vbasedev->migration; 467 int ret; 468 469 ret = vfio_update_pending(vbasedev); 470 if (ret) { 471 return; 472 } 473 474 *res_precopy_only += migration->pending_bytes; 475 476 trace_vfio_save_pending(vbasedev->name, *res_precopy_only, 477 *res_postcopy_only, *res_compatible); 478 } 479 480 static int vfio_save_iterate(QEMUFile *f, void *opaque) 481 { 482 VFIODevice *vbasedev = opaque; 483 VFIOMigration *migration = vbasedev->migration; 484 uint64_t data_size; 485 int ret; 486 487 qemu_put_be64(f, VFIO_MIG_FLAG_DEV_DATA_STATE); 488 489 if (migration->pending_bytes == 0) { 490 ret = vfio_update_pending(vbasedev); 491 if (ret) { 492 return ret; 493 } 494 495 if (migration->pending_bytes == 0) { 496 qemu_put_be64(f, 0); 497 qemu_put_be64(f, VFIO_MIG_FLAG_END_OF_STATE); 498 /* indicates data finished, goto complete phase */ 499 return 1; 500 } 501 } 502 503 ret = vfio_save_buffer(f, vbasedev, &data_size); 504 if (ret) { 505 error_report("%s: vfio_save_buffer failed %s", vbasedev->name, 506 strerror(errno)); 507 return ret; 508 } 509 510 qemu_put_be64(f, VFIO_MIG_FLAG_END_OF_STATE); 511 512 ret = qemu_file_get_error(f); 513 if (ret) { 514 return ret; 515 } 516 517 /* 518 * Reset pending_bytes as .save_live_pending is not called during savevm or 519 * snapshot case, in such case vfio_update_pending() at the start of this 520 * function updates pending_bytes. 521 */ 522 migration->pending_bytes = 0; 523 trace_vfio_save_iterate(vbasedev->name, data_size); 524 return 0; 525 } 526 527 static int vfio_save_complete_precopy(QEMUFile *f, void *opaque) 528 { 529 VFIODevice *vbasedev = opaque; 530 VFIOMigration *migration = vbasedev->migration; 531 uint64_t data_size; 532 int ret; 533 534 ret = vfio_migration_set_state(vbasedev, ~VFIO_DEVICE_STATE_RUNNING, 535 VFIO_DEVICE_STATE_SAVING); 536 if (ret) { 537 error_report("%s: Failed to set state STOP and SAVING", 538 vbasedev->name); 539 return ret; 540 } 541 542 ret = vfio_update_pending(vbasedev); 543 if (ret) { 544 return ret; 545 } 546 547 while (migration->pending_bytes > 0) { 548 qemu_put_be64(f, VFIO_MIG_FLAG_DEV_DATA_STATE); 549 ret = vfio_save_buffer(f, vbasedev, &data_size); 550 if (ret < 0) { 551 error_report("%s: Failed to save buffer", vbasedev->name); 552 return ret; 553 } 554 555 if (data_size == 0) { 556 break; 557 } 558 559 ret = vfio_update_pending(vbasedev); 560 if (ret) { 561 return ret; 562 } 563 } 564 565 qemu_put_be64(f, VFIO_MIG_FLAG_END_OF_STATE); 566 567 ret = qemu_file_get_error(f); 568 if (ret) { 569 return ret; 570 } 571 572 ret = vfio_migration_set_state(vbasedev, ~VFIO_DEVICE_STATE_SAVING, 0); 573 if (ret) { 574 error_report("%s: Failed to set state STOPPED", vbasedev->name); 575 return ret; 576 } 577 578 trace_vfio_save_complete_precopy(vbasedev->name); 579 return ret; 580 } 581 582 static void vfio_save_state(QEMUFile *f, void *opaque) 583 { 584 VFIODevice *vbasedev = opaque; 585 int ret; 586 587 ret = vfio_save_device_config_state(f, opaque); 588 if (ret) { 589 error_report("%s: Failed to save device config space", 590 vbasedev->name); 591 qemu_file_set_error(f, ret); 592 } 593 } 594 595 static int vfio_load_setup(QEMUFile *f, void *opaque) 596 { 597 VFIODevice *vbasedev = opaque; 598 VFIOMigration *migration = vbasedev->migration; 599 int ret = 0; 600 601 if (migration->region.mmaps) { 602 ret = vfio_region_mmap(&migration->region); 603 if (ret) { 604 error_report("%s: Failed to mmap VFIO migration region %d: %s", 605 vbasedev->name, migration->region.nr, 606 strerror(-ret)); 607 error_report("%s: Falling back to slow path", vbasedev->name); 608 } 609 } 610 611 ret = vfio_migration_set_state(vbasedev, ~VFIO_DEVICE_STATE_MASK, 612 VFIO_DEVICE_STATE_RESUMING); 613 if (ret) { 614 error_report("%s: Failed to set state RESUMING", vbasedev->name); 615 if (migration->region.mmaps) { 616 vfio_region_unmap(&migration->region); 617 } 618 } 619 return ret; 620 } 621 622 static int vfio_load_cleanup(void *opaque) 623 { 624 VFIODevice *vbasedev = opaque; 625 626 vfio_migration_cleanup(vbasedev); 627 trace_vfio_load_cleanup(vbasedev->name); 628 return 0; 629 } 630 631 static int vfio_load_state(QEMUFile *f, void *opaque, int version_id) 632 { 633 VFIODevice *vbasedev = opaque; 634 int ret = 0; 635 uint64_t data; 636 637 data = qemu_get_be64(f); 638 while (data != VFIO_MIG_FLAG_END_OF_STATE) { 639 640 trace_vfio_load_state(vbasedev->name, data); 641 642 switch (data) { 643 case VFIO_MIG_FLAG_DEV_CONFIG_STATE: 644 { 645 return vfio_load_device_config_state(f, opaque); 646 } 647 case VFIO_MIG_FLAG_DEV_SETUP_STATE: 648 { 649 data = qemu_get_be64(f); 650 if (data == VFIO_MIG_FLAG_END_OF_STATE) { 651 return ret; 652 } else { 653 error_report("%s: SETUP STATE: EOS not found 0x%"PRIx64, 654 vbasedev->name, data); 655 return -EINVAL; 656 } 657 break; 658 } 659 case VFIO_MIG_FLAG_DEV_DATA_STATE: 660 { 661 uint64_t data_size = qemu_get_be64(f); 662 663 if (data_size) { 664 ret = vfio_load_buffer(f, vbasedev, data_size); 665 if (ret < 0) { 666 return ret; 667 } 668 } 669 break; 670 } 671 default: 672 error_report("%s: Unknown tag 0x%"PRIx64, vbasedev->name, data); 673 return -EINVAL; 674 } 675 676 data = qemu_get_be64(f); 677 ret = qemu_file_get_error(f); 678 if (ret) { 679 return ret; 680 } 681 } 682 return ret; 683 } 684 685 static SaveVMHandlers savevm_vfio_handlers = { 686 .save_setup = vfio_save_setup, 687 .save_cleanup = vfio_save_cleanup, 688 .save_live_pending = vfio_save_pending, 689 .save_live_iterate = vfio_save_iterate, 690 .save_live_complete_precopy = vfio_save_complete_precopy, 691 .save_state = vfio_save_state, 692 .load_setup = vfio_load_setup, 693 .load_cleanup = vfio_load_cleanup, 694 .load_state = vfio_load_state, 695 }; 696 697 /* ---------------------------------------------------------------------- */ 698 699 static void vfio_vmstate_change(void *opaque, bool running, RunState state) 700 { 701 VFIODevice *vbasedev = opaque; 702 VFIOMigration *migration = vbasedev->migration; 703 uint32_t value, mask; 704 int ret; 705 706 if (vbasedev->migration->vm_running == running) { 707 return; 708 } 709 710 if (running) { 711 /* 712 * Here device state can have one of _SAVING, _RESUMING or _STOP bit. 713 * Transition from _SAVING to _RUNNING can happen if there is migration 714 * failure, in that case clear _SAVING bit. 715 * Transition from _RESUMING to _RUNNING occurs during resuming 716 * phase, in that case clear _RESUMING bit. 717 * In both the above cases, set _RUNNING bit. 718 */ 719 mask = ~VFIO_DEVICE_STATE_MASK; 720 value = VFIO_DEVICE_STATE_RUNNING; 721 } else { 722 /* 723 * Here device state could be either _RUNNING or _SAVING|_RUNNING. Reset 724 * _RUNNING bit 725 */ 726 mask = ~VFIO_DEVICE_STATE_RUNNING; 727 728 /* 729 * When VM state transition to stop for savevm command, device should 730 * start saving data. 731 */ 732 if (state == RUN_STATE_SAVE_VM) { 733 value = VFIO_DEVICE_STATE_SAVING; 734 } else { 735 value = 0; 736 } 737 } 738 739 ret = vfio_migration_set_state(vbasedev, mask, value); 740 if (ret) { 741 /* 742 * Migration should be aborted in this case, but vm_state_notify() 743 * currently does not support reporting failures. 744 */ 745 error_report("%s: Failed to set device state 0x%x", vbasedev->name, 746 (migration->device_state & mask) | value); 747 qemu_file_set_error(migrate_get_current()->to_dst_file, ret); 748 } 749 vbasedev->migration->vm_running = running; 750 trace_vfio_vmstate_change(vbasedev->name, running, RunState_str(state), 751 (migration->device_state & mask) | value); 752 } 753 754 static void vfio_migration_state_notifier(Notifier *notifier, void *data) 755 { 756 MigrationState *s = data; 757 VFIOMigration *migration = container_of(notifier, VFIOMigration, 758 migration_state); 759 VFIODevice *vbasedev = migration->vbasedev; 760 int ret; 761 762 trace_vfio_migration_state_notifier(vbasedev->name, 763 MigrationStatus_str(s->state)); 764 765 switch (s->state) { 766 case MIGRATION_STATUS_CANCELLING: 767 case MIGRATION_STATUS_CANCELLED: 768 case MIGRATION_STATUS_FAILED: 769 bytes_transferred = 0; 770 ret = vfio_migration_set_state(vbasedev, 771 ~(VFIO_DEVICE_STATE_SAVING | VFIO_DEVICE_STATE_RESUMING), 772 VFIO_DEVICE_STATE_RUNNING); 773 if (ret) { 774 error_report("%s: Failed to set state RUNNING", vbasedev->name); 775 } 776 } 777 } 778 779 static void vfio_migration_exit(VFIODevice *vbasedev) 780 { 781 VFIOMigration *migration = vbasedev->migration; 782 783 vfio_region_exit(&migration->region); 784 vfio_region_finalize(&migration->region); 785 g_free(vbasedev->migration); 786 vbasedev->migration = NULL; 787 } 788 789 static int vfio_migration_init(VFIODevice *vbasedev, 790 struct vfio_region_info *info) 791 { 792 int ret; 793 Object *obj; 794 VFIOMigration *migration; 795 char id[256] = ""; 796 g_autofree char *path = NULL, *oid = NULL; 797 798 if (!vbasedev->ops->vfio_get_object) { 799 return -EINVAL; 800 } 801 802 obj = vbasedev->ops->vfio_get_object(vbasedev); 803 if (!obj) { 804 return -EINVAL; 805 } 806 807 vbasedev->migration = g_new0(VFIOMigration, 1); 808 809 ret = vfio_region_setup(obj, vbasedev, &vbasedev->migration->region, 810 info->index, "migration"); 811 if (ret) { 812 error_report("%s: Failed to setup VFIO migration region %d: %s", 813 vbasedev->name, info->index, strerror(-ret)); 814 goto err; 815 } 816 817 if (!vbasedev->migration->region.size) { 818 error_report("%s: Invalid zero-sized VFIO migration region %d", 819 vbasedev->name, info->index); 820 ret = -EINVAL; 821 goto err; 822 } 823 824 migration = vbasedev->migration; 825 migration->vbasedev = vbasedev; 826 827 oid = vmstate_if_get_id(VMSTATE_IF(DEVICE(obj))); 828 if (oid) { 829 path = g_strdup_printf("%s/vfio", oid); 830 } else { 831 path = g_strdup("vfio"); 832 } 833 strpadcpy(id, sizeof(id), path, '\0'); 834 835 register_savevm_live(id, VMSTATE_INSTANCE_ID_ANY, 1, &savevm_vfio_handlers, 836 vbasedev); 837 838 migration->vm_state = qdev_add_vm_change_state_handler(vbasedev->dev, 839 vfio_vmstate_change, 840 vbasedev); 841 migration->migration_state.notify = vfio_migration_state_notifier; 842 add_migration_state_change_notifier(&migration->migration_state); 843 return 0; 844 845 err: 846 vfio_migration_exit(vbasedev); 847 return ret; 848 } 849 850 /* ---------------------------------------------------------------------- */ 851 852 int64_t vfio_mig_bytes_transferred(void) 853 { 854 return bytes_transferred; 855 } 856 857 int vfio_migration_probe(VFIODevice *vbasedev, Error **errp) 858 { 859 VFIOContainer *container = vbasedev->group->container; 860 struct vfio_region_info *info = NULL; 861 int ret = -ENOTSUP; 862 863 if (!vbasedev->enable_migration || !container->dirty_pages_supported) { 864 goto add_blocker; 865 } 866 867 ret = vfio_get_dev_region_info(vbasedev, VFIO_REGION_TYPE_MIGRATION, 868 VFIO_REGION_SUBTYPE_MIGRATION, &info); 869 if (ret) { 870 goto add_blocker; 871 } 872 873 ret = vfio_migration_init(vbasedev, info); 874 if (ret) { 875 goto add_blocker; 876 } 877 878 trace_vfio_migration_probe(vbasedev->name, info->index); 879 g_free(info); 880 return 0; 881 882 add_blocker: 883 error_setg(&vbasedev->migration_blocker, 884 "VFIO device doesn't support migration"); 885 g_free(info); 886 887 ret = migrate_add_blocker(vbasedev->migration_blocker, errp); 888 if (ret < 0) { 889 error_free(vbasedev->migration_blocker); 890 vbasedev->migration_blocker = NULL; 891 } 892 return ret; 893 } 894 895 void vfio_migration_finalize(VFIODevice *vbasedev) 896 { 897 if (vbasedev->migration) { 898 VFIOMigration *migration = vbasedev->migration; 899 900 remove_migration_state_change_notifier(&migration->migration_state); 901 qemu_del_vm_change_state_handler(migration->vm_state); 902 unregister_savevm(VMSTATE_IF(vbasedev->dev), "vfio", vbasedev); 903 vfio_migration_exit(vbasedev); 904 } 905 906 if (vbasedev->migration_blocker) { 907 migrate_del_blocker(vbasedev->migration_blocker); 908 error_free(vbasedev->migration_blocker); 909 vbasedev->migration_blocker = NULL; 910 } 911 } 912