1 /* 2 * Block driver for Hyper-V VHDX Images 3 * 4 * Copyright (c) 2013 Red Hat, Inc., 5 * 6 * Authors: 7 * Jeff Cody <jcody@redhat.com> 8 * 9 * This is based on the "VHDX Format Specification v1.00", published 8/25/2012 10 * by Microsoft: 11 * https://www.microsoft.com/en-us/download/details.aspx?id=34750 12 * 13 * This work is licensed under the terms of the GNU LGPL, version 2 or later. 14 * See the COPYING.LIB file in the top-level directory. 15 * 16 */ 17 18 #include "qemu/osdep.h" 19 #include "qapi/error.h" 20 #include "block/block_int.h" 21 #include "block/qdict.h" 22 #include "sysemu/block-backend.h" 23 #include "qemu/module.h" 24 #include "qemu/option.h" 25 #include "qemu/crc32c.h" 26 #include "qemu/bswap.h" 27 #include "vhdx.h" 28 #include "migration/blocker.h" 29 #include "qemu/uuid.h" 30 #include "qapi/qmp/qdict.h" 31 #include "qapi/qobject-input-visitor.h" 32 #include "qapi/qapi-visit-block-core.h" 33 34 /* Options for VHDX creation */ 35 36 #define VHDX_BLOCK_OPT_LOG_SIZE "log_size" 37 #define VHDX_BLOCK_OPT_BLOCK_SIZE "block_size" 38 #define VHDX_BLOCK_OPT_ZERO "block_state_zero" 39 40 typedef enum VHDXImageType { 41 VHDX_TYPE_DYNAMIC = 0, 42 VHDX_TYPE_FIXED, 43 VHDX_TYPE_DIFFERENCING, /* Currently unsupported */ 44 } VHDXImageType; 45 46 static QemuOptsList vhdx_create_opts; 47 48 /* Several metadata and region table data entries are identified by 49 * guids in a MS-specific GUID format. */ 50 51 52 /* ------- Known Region Table GUIDs ---------------------- */ 53 static const MSGUID bat_guid = { .data1 = 0x2dc27766, 54 .data2 = 0xf623, 55 .data3 = 0x4200, 56 .data4 = { 0x9d, 0x64, 0x11, 0x5e, 57 0x9b, 0xfd, 0x4a, 0x08} }; 58 59 static const MSGUID metadata_guid = { .data1 = 0x8b7ca206, 60 .data2 = 0x4790, 61 .data3 = 0x4b9a, 62 .data4 = { 0xb8, 0xfe, 0x57, 0x5f, 63 0x05, 0x0f, 0x88, 0x6e} }; 64 65 66 67 /* ------- Known Metadata Entry GUIDs ---------------------- */ 68 static const MSGUID file_param_guid = { .data1 = 0xcaa16737, 69 .data2 = 0xfa36, 70 .data3 = 0x4d43, 71 .data4 = { 0xb3, 0xb6, 0x33, 0xf0, 72 0xaa, 0x44, 0xe7, 0x6b} }; 73 74 static const MSGUID virtual_size_guid = { .data1 = 0x2FA54224, 75 .data2 = 0xcd1b, 76 .data3 = 0x4876, 77 .data4 = { 0xb2, 0x11, 0x5d, 0xbe, 78 0xd8, 0x3b, 0xf4, 0xb8} }; 79 80 static const MSGUID page83_guid = { .data1 = 0xbeca12ab, 81 .data2 = 0xb2e6, 82 .data3 = 0x4523, 83 .data4 = { 0x93, 0xef, 0xc3, 0x09, 84 0xe0, 0x00, 0xc7, 0x46} }; 85 86 87 static const MSGUID phys_sector_guid = { .data1 = 0xcda348c7, 88 .data2 = 0x445d, 89 .data3 = 0x4471, 90 .data4 = { 0x9c, 0xc9, 0xe9, 0x88, 91 0x52, 0x51, 0xc5, 0x56} }; 92 93 static const MSGUID parent_locator_guid = { .data1 = 0xa8d35f2d, 94 .data2 = 0xb30b, 95 .data3 = 0x454d, 96 .data4 = { 0xab, 0xf7, 0xd3, 97 0xd8, 0x48, 0x34, 98 0xab, 0x0c} }; 99 100 static const MSGUID logical_sector_guid = { .data1 = 0x8141bf1d, 101 .data2 = 0xa96f, 102 .data3 = 0x4709, 103 .data4 = { 0xba, 0x47, 0xf2, 104 0x33, 0xa8, 0xfa, 105 0xab, 0x5f} }; 106 107 /* Each parent type must have a valid GUID; this is for parent images 108 * of type 'VHDX'. If we were to allow e.g. a QCOW2 parent, we would 109 * need to make up our own QCOW2 GUID type */ 110 static const MSGUID parent_vhdx_guid __attribute__((unused)) 111 = { .data1 = 0xb04aefb7, 112 .data2 = 0xd19e, 113 .data3 = 0x4a81, 114 .data4 = { 0xb7, 0x89, 0x25, 0xb8, 115 0xe9, 0x44, 0x59, 0x13} }; 116 117 118 #define META_FILE_PARAMETER_PRESENT 0x01 119 #define META_VIRTUAL_DISK_SIZE_PRESENT 0x02 120 #define META_PAGE_83_PRESENT 0x04 121 #define META_LOGICAL_SECTOR_SIZE_PRESENT 0x08 122 #define META_PHYS_SECTOR_SIZE_PRESENT 0x10 123 #define META_PARENT_LOCATOR_PRESENT 0x20 124 125 #define META_ALL_PRESENT \ 126 (META_FILE_PARAMETER_PRESENT | META_VIRTUAL_DISK_SIZE_PRESENT | \ 127 META_PAGE_83_PRESENT | META_LOGICAL_SECTOR_SIZE_PRESENT | \ 128 META_PHYS_SECTOR_SIZE_PRESENT) 129 130 131 typedef struct VHDXSectorInfo { 132 uint32_t bat_idx; /* BAT entry index */ 133 uint32_t sectors_avail; /* sectors available in payload block */ 134 uint32_t bytes_left; /* bytes left in the block after data to r/w */ 135 uint32_t bytes_avail; /* bytes available in payload block */ 136 uint64_t file_offset; /* absolute offset in bytes, in file */ 137 uint64_t block_offset; /* block offset, in bytes */ 138 } VHDXSectorInfo; 139 140 /* Calculates new checksum. 141 * 142 * Zero is substituted during crc calculation for the original crc field 143 * crc_offset: byte offset in buf of the buffer crc 144 * buf: buffer pointer 145 * size: size of buffer (must be > crc_offset+4) 146 * 147 * Note: The buffer should have all multi-byte data in little-endian format, 148 * and the resulting checksum is in little endian format. 149 */ 150 uint32_t vhdx_update_checksum(uint8_t *buf, size_t size, int crc_offset) 151 { 152 uint32_t crc; 153 154 assert(buf != NULL); 155 assert(size > (crc_offset + sizeof(crc))); 156 157 memset(buf + crc_offset, 0, sizeof(crc)); 158 crc = crc32c(0xffffffff, buf, size); 159 cpu_to_le32s(&crc); 160 memcpy(buf + crc_offset, &crc, sizeof(crc)); 161 162 return crc; 163 } 164 165 uint32_t vhdx_checksum_calc(uint32_t crc, uint8_t *buf, size_t size, 166 int crc_offset) 167 { 168 uint32_t crc_new; 169 uint32_t crc_orig; 170 assert(buf != NULL); 171 172 if (crc_offset > 0) { 173 memcpy(&crc_orig, buf + crc_offset, sizeof(crc_orig)); 174 memset(buf + crc_offset, 0, sizeof(crc_orig)); 175 } 176 177 crc_new = crc32c(crc, buf, size); 178 if (crc_offset > 0) { 179 memcpy(buf + crc_offset, &crc_orig, sizeof(crc_orig)); 180 } 181 182 return crc_new; 183 } 184 185 /* Validates the checksum of the buffer, with an in-place CRC. 186 * 187 * Zero is substituted during crc calculation for the original crc field, 188 * and the crc field is restored afterwards. But the buffer will be modified 189 * during the calculation, so this may not be not suitable for multi-threaded 190 * use. 191 * 192 * crc_offset: byte offset in buf of the buffer crc 193 * buf: buffer pointer 194 * size: size of buffer (must be > crc_offset+4) 195 * 196 * returns true if checksum is valid, false otherwise 197 */ 198 bool vhdx_checksum_is_valid(uint8_t *buf, size_t size, int crc_offset) 199 { 200 uint32_t crc_orig; 201 uint32_t crc; 202 203 assert(buf != NULL); 204 assert(size > (crc_offset + 4)); 205 206 memcpy(&crc_orig, buf + crc_offset, sizeof(crc_orig)); 207 crc_orig = le32_to_cpu(crc_orig); 208 209 crc = vhdx_checksum_calc(0xffffffff, buf, size, crc_offset); 210 211 return crc == crc_orig; 212 } 213 214 215 /* 216 * This generates a UUID that is compliant with the MS GUIDs used 217 * in the VHDX spec (and elsewhere). 218 */ 219 void vhdx_guid_generate(MSGUID *guid) 220 { 221 QemuUUID uuid; 222 assert(guid != NULL); 223 224 qemu_uuid_generate(&uuid); 225 memcpy(guid, &uuid, sizeof(MSGUID)); 226 } 227 228 /* Check for region overlaps inside the VHDX image */ 229 static int vhdx_region_check(BDRVVHDXState *s, uint64_t start, uint64_t length) 230 { 231 int ret = 0; 232 uint64_t end; 233 VHDXRegionEntry *r; 234 235 end = start + length; 236 QLIST_FOREACH(r, &s->regions, entries) { 237 if (!((start >= r->end) || (end <= r->start))) { 238 ret = -EINVAL; 239 goto exit; 240 } 241 } 242 243 exit: 244 return ret; 245 } 246 247 /* Register a region for future checks */ 248 static void vhdx_region_register(BDRVVHDXState *s, 249 uint64_t start, uint64_t length) 250 { 251 VHDXRegionEntry *r; 252 253 r = g_malloc0(sizeof(*r)); 254 255 r->start = start; 256 r->end = start + length; 257 258 QLIST_INSERT_HEAD(&s->regions, r, entries); 259 } 260 261 /* Free all registered regions */ 262 static void vhdx_region_unregister_all(BDRVVHDXState *s) 263 { 264 VHDXRegionEntry *r, *r_next; 265 266 QLIST_FOREACH_SAFE(r, &s->regions, entries, r_next) { 267 QLIST_REMOVE(r, entries); 268 g_free(r); 269 } 270 } 271 272 static void vhdx_set_shift_bits(BDRVVHDXState *s) 273 { 274 s->logical_sector_size_bits = ctz32(s->logical_sector_size); 275 s->sectors_per_block_bits = ctz32(s->sectors_per_block); 276 s->chunk_ratio_bits = ctz64(s->chunk_ratio); 277 s->block_size_bits = ctz32(s->block_size); 278 } 279 280 /* 281 * Per the MS VHDX Specification, for every VHDX file: 282 * - The header section is fixed size - 1 MB 283 * - The header section is always the first "object" 284 * - The first 64KB of the header is the File Identifier 285 * - The first uint64 (8 bytes) is the VHDX Signature ("vhdxfile") 286 * - The following 512 bytes constitute a UTF-16 string identifiying the 287 * software that created the file, and is optional and diagnostic only. 288 * 289 * Therefore, we probe by looking for the vhdxfile signature "vhdxfile" 290 */ 291 static int vhdx_probe(const uint8_t *buf, int buf_size, const char *filename) 292 { 293 if (buf_size >= 8 && !memcmp(buf, "vhdxfile", 8)) { 294 return 100; 295 } 296 return 0; 297 } 298 299 /* 300 * Writes the header to the specified offset. 301 * 302 * This will optionally read in buffer data from disk (otherwise zero-fill), 303 * and then update the header checksum. Header is converted to proper 304 * endianness before being written to the specified file offset 305 */ 306 static int vhdx_write_header(BdrvChild *file, VHDXHeader *hdr, 307 uint64_t offset, bool read) 308 { 309 BlockDriverState *bs_file = file->bs; 310 uint8_t *buffer = NULL; 311 int ret; 312 VHDXHeader *header_le; 313 314 assert(bs_file != NULL); 315 assert(hdr != NULL); 316 317 /* the header checksum is not over just the packed size of VHDXHeader, 318 * but rather over the entire 'reserved' range for the header, which is 319 * 4KB (VHDX_HEADER_SIZE). */ 320 321 buffer = qemu_blockalign(bs_file, VHDX_HEADER_SIZE); 322 if (read) { 323 /* if true, we can't assume the extra reserved bytes are 0 */ 324 ret = bdrv_pread(file, offset, buffer, VHDX_HEADER_SIZE); 325 if (ret < 0) { 326 goto exit; 327 } 328 } else { 329 memset(buffer, 0, VHDX_HEADER_SIZE); 330 } 331 332 /* overwrite the actual VHDXHeader portion */ 333 header_le = (VHDXHeader *)buffer; 334 memcpy(header_le, hdr, sizeof(VHDXHeader)); 335 vhdx_header_le_export(hdr, header_le); 336 vhdx_update_checksum(buffer, VHDX_HEADER_SIZE, 337 offsetof(VHDXHeader, checksum)); 338 ret = bdrv_pwrite_sync(file, offset, header_le, sizeof(VHDXHeader)); 339 340 exit: 341 qemu_vfree(buffer); 342 return ret; 343 } 344 345 /* Update the VHDX headers 346 * 347 * This follows the VHDX spec procedures for header updates. 348 * 349 * - non-current header is updated with largest sequence number 350 */ 351 static int vhdx_update_header(BlockDriverState *bs, BDRVVHDXState *s, 352 bool generate_data_write_guid, MSGUID *log_guid) 353 { 354 int ret = 0; 355 int hdr_idx = 0; 356 uint64_t header_offset = VHDX_HEADER1_OFFSET; 357 358 VHDXHeader *active_header; 359 VHDXHeader *inactive_header; 360 361 /* operate on the non-current header */ 362 if (s->curr_header == 0) { 363 hdr_idx = 1; 364 header_offset = VHDX_HEADER2_OFFSET; 365 } 366 367 active_header = s->headers[s->curr_header]; 368 inactive_header = s->headers[hdr_idx]; 369 370 inactive_header->sequence_number = active_header->sequence_number + 1; 371 372 /* a new file guid must be generated before any file write, including 373 * headers */ 374 inactive_header->file_write_guid = s->session_guid; 375 376 /* a new data guid only needs to be generated before any guest-visible 377 * writes (i.e. something observable via virtual disk read) */ 378 if (generate_data_write_guid) { 379 vhdx_guid_generate(&inactive_header->data_write_guid); 380 } 381 382 /* update the log guid if present */ 383 if (log_guid) { 384 inactive_header->log_guid = *log_guid; 385 } 386 387 ret = vhdx_write_header(bs->file, inactive_header, header_offset, true); 388 if (ret < 0) { 389 goto exit; 390 } 391 s->curr_header = hdr_idx; 392 393 exit: 394 return ret; 395 } 396 397 /* 398 * The VHDX spec calls for header updates to be performed twice, so that both 399 * the current and non-current header have valid info 400 */ 401 int vhdx_update_headers(BlockDriverState *bs, BDRVVHDXState *s, 402 bool generate_data_write_guid, MSGUID *log_guid) 403 { 404 int ret; 405 406 ret = vhdx_update_header(bs, s, generate_data_write_guid, log_guid); 407 if (ret < 0) { 408 return ret; 409 } 410 ret = vhdx_update_header(bs, s, generate_data_write_guid, log_guid); 411 return ret; 412 } 413 414 /* opens the specified header block from the VHDX file header section */ 415 static void vhdx_parse_header(BlockDriverState *bs, BDRVVHDXState *s, 416 Error **errp) 417 { 418 int ret; 419 VHDXHeader *header1; 420 VHDXHeader *header2; 421 bool h1_valid = false; 422 bool h2_valid = false; 423 uint64_t h1_seq = 0; 424 uint64_t h2_seq = 0; 425 uint8_t *buffer; 426 427 /* header1 & header2 are freed in vhdx_close() */ 428 header1 = qemu_blockalign(bs, sizeof(VHDXHeader)); 429 header2 = qemu_blockalign(bs, sizeof(VHDXHeader)); 430 431 buffer = qemu_blockalign(bs, VHDX_HEADER_SIZE); 432 433 s->headers[0] = header1; 434 s->headers[1] = header2; 435 436 /* We have to read the whole VHDX_HEADER_SIZE instead of 437 * sizeof(VHDXHeader), because the checksum is over the whole 438 * region */ 439 ret = bdrv_pread(bs->file, VHDX_HEADER1_OFFSET, buffer, 440 VHDX_HEADER_SIZE); 441 if (ret < 0) { 442 goto fail; 443 } 444 /* copy over just the relevant portion that we need */ 445 memcpy(header1, buffer, sizeof(VHDXHeader)); 446 447 if (vhdx_checksum_is_valid(buffer, VHDX_HEADER_SIZE, 4)) { 448 vhdx_header_le_import(header1); 449 if (header1->signature == VHDX_HEADER_SIGNATURE && 450 header1->version == 1) { 451 h1_seq = header1->sequence_number; 452 h1_valid = true; 453 } 454 } 455 456 ret = bdrv_pread(bs->file, VHDX_HEADER2_OFFSET, buffer, 457 VHDX_HEADER_SIZE); 458 if (ret < 0) { 459 goto fail; 460 } 461 /* copy over just the relevant portion that we need */ 462 memcpy(header2, buffer, sizeof(VHDXHeader)); 463 464 if (vhdx_checksum_is_valid(buffer, VHDX_HEADER_SIZE, 4)) { 465 vhdx_header_le_import(header2); 466 if (header2->signature == VHDX_HEADER_SIGNATURE && 467 header2->version == 1) { 468 h2_seq = header2->sequence_number; 469 h2_valid = true; 470 } 471 } 472 473 /* If there is only 1 valid header (or no valid headers), we 474 * don't care what the sequence numbers are */ 475 if (h1_valid && !h2_valid) { 476 s->curr_header = 0; 477 } else if (!h1_valid && h2_valid) { 478 s->curr_header = 1; 479 } else if (!h1_valid && !h2_valid) { 480 goto fail; 481 } else { 482 /* If both headers are valid, then we choose the active one by the 483 * highest sequence number. If the sequence numbers are equal, that is 484 * invalid */ 485 if (h1_seq > h2_seq) { 486 s->curr_header = 0; 487 } else if (h2_seq > h1_seq) { 488 s->curr_header = 1; 489 } else { 490 /* The Microsoft Disk2VHD tool will create 2 identical 491 * headers, with identical sequence numbers. If the headers are 492 * identical, don't consider the file corrupt */ 493 if (!memcmp(header1, header2, sizeof(VHDXHeader))) { 494 s->curr_header = 0; 495 } else { 496 goto fail; 497 } 498 } 499 } 500 501 vhdx_region_register(s, s->headers[s->curr_header]->log_offset, 502 s->headers[s->curr_header]->log_length); 503 goto exit; 504 505 fail: 506 error_setg_errno(errp, -ret, "No valid VHDX header found"); 507 qemu_vfree(header1); 508 qemu_vfree(header2); 509 s->headers[0] = NULL; 510 s->headers[1] = NULL; 511 exit: 512 qemu_vfree(buffer); 513 } 514 515 516 static int vhdx_open_region_tables(BlockDriverState *bs, BDRVVHDXState *s) 517 { 518 int ret = 0; 519 uint8_t *buffer; 520 int offset = 0; 521 VHDXRegionTableEntry rt_entry; 522 uint32_t i; 523 bool bat_rt_found = false; 524 bool metadata_rt_found = false; 525 526 /* We have to read the whole 64KB block, because the crc32 is over the 527 * whole block */ 528 buffer = qemu_blockalign(bs, VHDX_HEADER_BLOCK_SIZE); 529 530 ret = bdrv_pread(bs->file, VHDX_REGION_TABLE_OFFSET, buffer, 531 VHDX_HEADER_BLOCK_SIZE); 532 if (ret < 0) { 533 goto fail; 534 } 535 memcpy(&s->rt, buffer, sizeof(s->rt)); 536 offset += sizeof(s->rt); 537 538 if (!vhdx_checksum_is_valid(buffer, VHDX_HEADER_BLOCK_SIZE, 4)) { 539 ret = -EINVAL; 540 goto fail; 541 } 542 543 vhdx_region_header_le_import(&s->rt); 544 545 if (s->rt.signature != VHDX_REGION_SIGNATURE) { 546 ret = -EINVAL; 547 goto fail; 548 } 549 550 551 /* Per spec, maximum region table entry count is 2047 */ 552 if (s->rt.entry_count > 2047) { 553 ret = -EINVAL; 554 goto fail; 555 } 556 557 for (i = 0; i < s->rt.entry_count; i++) { 558 memcpy(&rt_entry, buffer + offset, sizeof(rt_entry)); 559 offset += sizeof(rt_entry); 560 561 vhdx_region_entry_le_import(&rt_entry); 562 563 /* check for region overlap between these entries, and any 564 * other memory regions in the file */ 565 ret = vhdx_region_check(s, rt_entry.file_offset, rt_entry.length); 566 if (ret < 0) { 567 goto fail; 568 } 569 570 vhdx_region_register(s, rt_entry.file_offset, rt_entry.length); 571 572 /* see if we recognize the entry */ 573 if (guid_eq(rt_entry.guid, bat_guid)) { 574 /* must be unique; if we have already found it this is invalid */ 575 if (bat_rt_found) { 576 ret = -EINVAL; 577 goto fail; 578 } 579 bat_rt_found = true; 580 s->bat_rt = rt_entry; 581 continue; 582 } 583 584 if (guid_eq(rt_entry.guid, metadata_guid)) { 585 /* must be unique; if we have already found it this is invalid */ 586 if (metadata_rt_found) { 587 ret = -EINVAL; 588 goto fail; 589 } 590 metadata_rt_found = true; 591 s->metadata_rt = rt_entry; 592 continue; 593 } 594 595 if (rt_entry.data_bits & VHDX_REGION_ENTRY_REQUIRED) { 596 /* cannot read vhdx file - required region table entry that 597 * we do not understand. per spec, we must fail to open */ 598 ret = -ENOTSUP; 599 goto fail; 600 } 601 } 602 603 if (!bat_rt_found || !metadata_rt_found) { 604 ret = -EINVAL; 605 goto fail; 606 } 607 608 ret = 0; 609 610 fail: 611 qemu_vfree(buffer); 612 return ret; 613 } 614 615 616 617 /* Metadata initial parser 618 * 619 * This loads all the metadata entry fields. This may cause additional 620 * fields to be processed (e.g. parent locator, etc..). 621 * 622 * There are 5 Metadata items that are always required: 623 * - File Parameters (block size, has a parent) 624 * - Virtual Disk Size (size, in bytes, of the virtual drive) 625 * - Page 83 Data (scsi page 83 guid) 626 * - Logical Sector Size (logical sector size in bytes, either 512 or 627 * 4096. We only support 512 currently) 628 * - Physical Sector Size (512 or 4096) 629 * 630 * Also, if the File Parameters indicate this is a differencing file, 631 * we must also look for the Parent Locator metadata item. 632 */ 633 static int vhdx_parse_metadata(BlockDriverState *bs, BDRVVHDXState *s) 634 { 635 int ret = 0; 636 uint8_t *buffer; 637 int offset = 0; 638 uint32_t i = 0; 639 VHDXMetadataTableEntry md_entry; 640 641 buffer = qemu_blockalign(bs, VHDX_METADATA_TABLE_MAX_SIZE); 642 643 ret = bdrv_pread(bs->file, s->metadata_rt.file_offset, buffer, 644 VHDX_METADATA_TABLE_MAX_SIZE); 645 if (ret < 0) { 646 goto exit; 647 } 648 memcpy(&s->metadata_hdr, buffer, sizeof(s->metadata_hdr)); 649 offset += sizeof(s->metadata_hdr); 650 651 vhdx_metadata_header_le_import(&s->metadata_hdr); 652 653 if (s->metadata_hdr.signature != VHDX_METADATA_SIGNATURE) { 654 ret = -EINVAL; 655 goto exit; 656 } 657 658 s->metadata_entries.present = 0; 659 660 if ((s->metadata_hdr.entry_count * sizeof(md_entry)) > 661 (VHDX_METADATA_TABLE_MAX_SIZE - offset)) { 662 ret = -EINVAL; 663 goto exit; 664 } 665 666 for (i = 0; i < s->metadata_hdr.entry_count; i++) { 667 memcpy(&md_entry, buffer + offset, sizeof(md_entry)); 668 offset += sizeof(md_entry); 669 670 vhdx_metadata_entry_le_import(&md_entry); 671 672 if (guid_eq(md_entry.item_id, file_param_guid)) { 673 if (s->metadata_entries.present & META_FILE_PARAMETER_PRESENT) { 674 ret = -EINVAL; 675 goto exit; 676 } 677 s->metadata_entries.file_parameters_entry = md_entry; 678 s->metadata_entries.present |= META_FILE_PARAMETER_PRESENT; 679 continue; 680 } 681 682 if (guid_eq(md_entry.item_id, virtual_size_guid)) { 683 if (s->metadata_entries.present & META_VIRTUAL_DISK_SIZE_PRESENT) { 684 ret = -EINVAL; 685 goto exit; 686 } 687 s->metadata_entries.virtual_disk_size_entry = md_entry; 688 s->metadata_entries.present |= META_VIRTUAL_DISK_SIZE_PRESENT; 689 continue; 690 } 691 692 if (guid_eq(md_entry.item_id, page83_guid)) { 693 if (s->metadata_entries.present & META_PAGE_83_PRESENT) { 694 ret = -EINVAL; 695 goto exit; 696 } 697 s->metadata_entries.page83_data_entry = md_entry; 698 s->metadata_entries.present |= META_PAGE_83_PRESENT; 699 continue; 700 } 701 702 if (guid_eq(md_entry.item_id, logical_sector_guid)) { 703 if (s->metadata_entries.present & 704 META_LOGICAL_SECTOR_SIZE_PRESENT) { 705 ret = -EINVAL; 706 goto exit; 707 } 708 s->metadata_entries.logical_sector_size_entry = md_entry; 709 s->metadata_entries.present |= META_LOGICAL_SECTOR_SIZE_PRESENT; 710 continue; 711 } 712 713 if (guid_eq(md_entry.item_id, phys_sector_guid)) { 714 if (s->metadata_entries.present & META_PHYS_SECTOR_SIZE_PRESENT) { 715 ret = -EINVAL; 716 goto exit; 717 } 718 s->metadata_entries.phys_sector_size_entry = md_entry; 719 s->metadata_entries.present |= META_PHYS_SECTOR_SIZE_PRESENT; 720 continue; 721 } 722 723 if (guid_eq(md_entry.item_id, parent_locator_guid)) { 724 if (s->metadata_entries.present & META_PARENT_LOCATOR_PRESENT) { 725 ret = -EINVAL; 726 goto exit; 727 } 728 s->metadata_entries.parent_locator_entry = md_entry; 729 s->metadata_entries.present |= META_PARENT_LOCATOR_PRESENT; 730 continue; 731 } 732 733 if (md_entry.data_bits & VHDX_META_FLAGS_IS_REQUIRED) { 734 /* cannot read vhdx file - required region table entry that 735 * we do not understand. per spec, we must fail to open */ 736 ret = -ENOTSUP; 737 goto exit; 738 } 739 } 740 741 if (s->metadata_entries.present != META_ALL_PRESENT) { 742 ret = -ENOTSUP; 743 goto exit; 744 } 745 746 ret = bdrv_pread(bs->file, 747 s->metadata_entries.file_parameters_entry.offset 748 + s->metadata_rt.file_offset, 749 &s->params, 750 sizeof(s->params)); 751 752 if (ret < 0) { 753 goto exit; 754 } 755 756 le32_to_cpus(&s->params.block_size); 757 le32_to_cpus(&s->params.data_bits); 758 759 760 /* We now have the file parameters, so we can tell if this is a 761 * differencing file (i.e.. has_parent), is dynamic or fixed 762 * sized (leave_blocks_allocated), and the block size */ 763 764 /* The parent locator required iff the file parameters has_parent set */ 765 if (s->params.data_bits & VHDX_PARAMS_HAS_PARENT) { 766 if (s->metadata_entries.present & META_PARENT_LOCATOR_PRESENT) { 767 /* TODO: parse parent locator fields */ 768 ret = -ENOTSUP; /* temp, until differencing files are supported */ 769 goto exit; 770 } else { 771 /* if has_parent is set, but there is not parent locator present, 772 * then that is an invalid combination */ 773 ret = -EINVAL; 774 goto exit; 775 } 776 } 777 778 /* determine virtual disk size, logical sector size, 779 * and phys sector size */ 780 781 ret = bdrv_pread(bs->file, 782 s->metadata_entries.virtual_disk_size_entry.offset 783 + s->metadata_rt.file_offset, 784 &s->virtual_disk_size, 785 sizeof(uint64_t)); 786 if (ret < 0) { 787 goto exit; 788 } 789 ret = bdrv_pread(bs->file, 790 s->metadata_entries.logical_sector_size_entry.offset 791 + s->metadata_rt.file_offset, 792 &s->logical_sector_size, 793 sizeof(uint32_t)); 794 if (ret < 0) { 795 goto exit; 796 } 797 ret = bdrv_pread(bs->file, 798 s->metadata_entries.phys_sector_size_entry.offset 799 + s->metadata_rt.file_offset, 800 &s->physical_sector_size, 801 sizeof(uint32_t)); 802 if (ret < 0) { 803 goto exit; 804 } 805 806 le64_to_cpus(&s->virtual_disk_size); 807 le32_to_cpus(&s->logical_sector_size); 808 le32_to_cpus(&s->physical_sector_size); 809 810 if (s->params.block_size < VHDX_BLOCK_SIZE_MIN || 811 s->params.block_size > VHDX_BLOCK_SIZE_MAX) { 812 ret = -EINVAL; 813 goto exit; 814 } 815 816 /* only 2 supported sector sizes */ 817 if (s->logical_sector_size != 512 && s->logical_sector_size != 4096) { 818 ret = -EINVAL; 819 goto exit; 820 } 821 822 /* Both block_size and sector_size are guaranteed powers of 2, below. 823 Due to range checks above, s->sectors_per_block can never be < 256 */ 824 s->sectors_per_block = s->params.block_size / s->logical_sector_size; 825 s->chunk_ratio = (VHDX_MAX_SECTORS_PER_BLOCK) * 826 (uint64_t)s->logical_sector_size / 827 (uint64_t)s->params.block_size; 828 829 /* These values are ones we will want to use for division / multiplication 830 * later on, and they are all guaranteed (per the spec) to be powers of 2, 831 * so we can take advantage of that for shift operations during 832 * reads/writes */ 833 if (s->logical_sector_size & (s->logical_sector_size - 1)) { 834 ret = -EINVAL; 835 goto exit; 836 } 837 if (s->sectors_per_block & (s->sectors_per_block - 1)) { 838 ret = -EINVAL; 839 goto exit; 840 } 841 if (s->chunk_ratio & (s->chunk_ratio - 1)) { 842 ret = -EINVAL; 843 goto exit; 844 } 845 s->block_size = s->params.block_size; 846 if (s->block_size & (s->block_size - 1)) { 847 ret = -EINVAL; 848 goto exit; 849 } 850 851 vhdx_set_shift_bits(s); 852 853 ret = 0; 854 855 exit: 856 qemu_vfree(buffer); 857 return ret; 858 } 859 860 /* 861 * Calculate the number of BAT entries, including sector 862 * bitmap entries. 863 */ 864 static void vhdx_calc_bat_entries(BDRVVHDXState *s) 865 { 866 uint32_t data_blocks_cnt, bitmap_blocks_cnt; 867 868 data_blocks_cnt = DIV_ROUND_UP(s->virtual_disk_size, s->block_size); 869 bitmap_blocks_cnt = DIV_ROUND_UP(data_blocks_cnt, s->chunk_ratio); 870 871 if (s->parent_entries) { 872 s->bat_entries = bitmap_blocks_cnt * (s->chunk_ratio + 1); 873 } else { 874 s->bat_entries = data_blocks_cnt + 875 ((data_blocks_cnt - 1) >> s->chunk_ratio_bits); 876 } 877 878 } 879 880 static void vhdx_close(BlockDriverState *bs) 881 { 882 BDRVVHDXState *s = bs->opaque; 883 qemu_vfree(s->headers[0]); 884 s->headers[0] = NULL; 885 qemu_vfree(s->headers[1]); 886 s->headers[1] = NULL; 887 qemu_vfree(s->bat); 888 s->bat = NULL; 889 qemu_vfree(s->parent_entries); 890 s->parent_entries = NULL; 891 migrate_del_blocker(s->migration_blocker); 892 error_free(s->migration_blocker); 893 qemu_vfree(s->log.hdr); 894 s->log.hdr = NULL; 895 vhdx_region_unregister_all(s); 896 } 897 898 static int vhdx_open(BlockDriverState *bs, QDict *options, int flags, 899 Error **errp) 900 { 901 BDRVVHDXState *s = bs->opaque; 902 int ret = 0; 903 uint32_t i; 904 uint64_t signature; 905 Error *local_err = NULL; 906 907 bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file, 908 false, errp); 909 if (!bs->file) { 910 return -EINVAL; 911 } 912 913 s->bat = NULL; 914 s->first_visible_write = true; 915 916 qemu_co_mutex_init(&s->lock); 917 QLIST_INIT(&s->regions); 918 919 /* validate the file signature */ 920 ret = bdrv_pread(bs->file, 0, &signature, sizeof(uint64_t)); 921 if (ret < 0) { 922 goto fail; 923 } 924 if (memcmp(&signature, "vhdxfile", 8)) { 925 ret = -EINVAL; 926 goto fail; 927 } 928 929 /* This is used for any header updates, for the file_write_guid. 930 * The spec dictates that a new value should be used for the first 931 * header update */ 932 vhdx_guid_generate(&s->session_guid); 933 934 vhdx_parse_header(bs, s, &local_err); 935 if (local_err != NULL) { 936 error_propagate(errp, local_err); 937 ret = -EINVAL; 938 goto fail; 939 } 940 941 ret = vhdx_parse_log(bs, s, &s->log_replayed_on_open, errp); 942 if (ret < 0) { 943 goto fail; 944 } 945 946 ret = vhdx_open_region_tables(bs, s); 947 if (ret < 0) { 948 goto fail; 949 } 950 951 ret = vhdx_parse_metadata(bs, s); 952 if (ret < 0) { 953 goto fail; 954 } 955 956 s->block_size = s->params.block_size; 957 958 /* the VHDX spec dictates that virtual_disk_size is always a multiple of 959 * logical_sector_size */ 960 bs->total_sectors = s->virtual_disk_size >> s->logical_sector_size_bits; 961 962 vhdx_calc_bat_entries(s); 963 964 s->bat_offset = s->bat_rt.file_offset; 965 966 if (s->bat_entries > s->bat_rt.length / sizeof(VHDXBatEntry)) { 967 /* BAT allocation is not large enough for all entries */ 968 ret = -EINVAL; 969 goto fail; 970 } 971 972 /* s->bat is freed in vhdx_close() */ 973 s->bat = qemu_try_blockalign(bs->file->bs, s->bat_rt.length); 974 if (s->bat == NULL) { 975 ret = -ENOMEM; 976 goto fail; 977 } 978 979 ret = bdrv_pread(bs->file, s->bat_offset, s->bat, s->bat_rt.length); 980 if (ret < 0) { 981 goto fail; 982 } 983 984 uint64_t payblocks = s->chunk_ratio; 985 /* endian convert, and verify populated BAT field file offsets against 986 * region table and log entries */ 987 for (i = 0; i < s->bat_entries; i++) { 988 le64_to_cpus(&s->bat[i]); 989 if (payblocks--) { 990 /* payload bat entries */ 991 if ((s->bat[i] & VHDX_BAT_STATE_BIT_MASK) == 992 PAYLOAD_BLOCK_FULLY_PRESENT) { 993 ret = vhdx_region_check(s, s->bat[i] & VHDX_BAT_FILE_OFF_MASK, 994 s->block_size); 995 if (ret < 0) { 996 goto fail; 997 } 998 } 999 } else { 1000 payblocks = s->chunk_ratio; 1001 /* Once differencing files are supported, verify sector bitmap 1002 * blocks here */ 1003 } 1004 } 1005 1006 /* Disable migration when VHDX images are used */ 1007 error_setg(&s->migration_blocker, "The vhdx format used by node '%s' " 1008 "does not support live migration", 1009 bdrv_get_device_or_node_name(bs)); 1010 ret = migrate_add_blocker(s->migration_blocker, &local_err); 1011 if (local_err) { 1012 error_propagate(errp, local_err); 1013 error_free(s->migration_blocker); 1014 goto fail; 1015 } 1016 1017 /* TODO: differencing files */ 1018 1019 return 0; 1020 fail: 1021 vhdx_close(bs); 1022 return ret; 1023 } 1024 1025 static int vhdx_reopen_prepare(BDRVReopenState *state, 1026 BlockReopenQueue *queue, Error **errp) 1027 { 1028 return 0; 1029 } 1030 1031 1032 /* 1033 * Perform sector to block offset translations, to get various 1034 * sector and file offsets into the image. See VHDXSectorInfo 1035 */ 1036 static void vhdx_block_translate(BDRVVHDXState *s, int64_t sector_num, 1037 int nb_sectors, VHDXSectorInfo *sinfo) 1038 { 1039 uint32_t block_offset; 1040 1041 sinfo->bat_idx = sector_num >> s->sectors_per_block_bits; 1042 /* effectively a modulo - this gives us the offset into the block 1043 * (in sector sizes) for our sector number */ 1044 block_offset = sector_num - (sinfo->bat_idx << s->sectors_per_block_bits); 1045 /* the chunk ratio gives us the interleaving of the sector 1046 * bitmaps, so we need to advance our page block index by the 1047 * sector bitmaps entry number */ 1048 sinfo->bat_idx += sinfo->bat_idx >> s->chunk_ratio_bits; 1049 1050 /* the number of sectors we can read/write in this cycle */ 1051 sinfo->sectors_avail = s->sectors_per_block - block_offset; 1052 1053 sinfo->bytes_left = sinfo->sectors_avail << s->logical_sector_size_bits; 1054 1055 if (sinfo->sectors_avail > nb_sectors) { 1056 sinfo->sectors_avail = nb_sectors; 1057 } 1058 1059 sinfo->bytes_avail = sinfo->sectors_avail << s->logical_sector_size_bits; 1060 1061 sinfo->file_offset = s->bat[sinfo->bat_idx] & VHDX_BAT_FILE_OFF_MASK; 1062 1063 sinfo->block_offset = block_offset << s->logical_sector_size_bits; 1064 1065 /* The file offset must be past the header section, so must be > 0 */ 1066 if (sinfo->file_offset == 0) { 1067 return; 1068 } 1069 1070 /* block offset is the offset in vhdx logical sectors, in 1071 * the payload data block. Convert that to a byte offset 1072 * in the block, and add in the payload data block offset 1073 * in the file, in bytes, to get the final read address */ 1074 1075 sinfo->file_offset += sinfo->block_offset; 1076 } 1077 1078 1079 static int vhdx_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) 1080 { 1081 BDRVVHDXState *s = bs->opaque; 1082 1083 bdi->cluster_size = s->block_size; 1084 1085 bdi->unallocated_blocks_are_zero = 1086 (s->params.data_bits & VHDX_PARAMS_HAS_PARENT) == 0; 1087 1088 return 0; 1089 } 1090 1091 1092 static coroutine_fn int vhdx_co_readv(BlockDriverState *bs, int64_t sector_num, 1093 int nb_sectors, QEMUIOVector *qiov) 1094 { 1095 BDRVVHDXState *s = bs->opaque; 1096 int ret = 0; 1097 VHDXSectorInfo sinfo; 1098 uint64_t bytes_done = 0; 1099 QEMUIOVector hd_qiov; 1100 1101 qemu_iovec_init(&hd_qiov, qiov->niov); 1102 1103 qemu_co_mutex_lock(&s->lock); 1104 1105 while (nb_sectors > 0) { 1106 /* We are a differencing file, so we need to inspect the sector bitmap 1107 * to see if we have the data or not */ 1108 if (s->params.data_bits & VHDX_PARAMS_HAS_PARENT) { 1109 /* not supported yet */ 1110 ret = -ENOTSUP; 1111 goto exit; 1112 } else { 1113 vhdx_block_translate(s, sector_num, nb_sectors, &sinfo); 1114 1115 qemu_iovec_reset(&hd_qiov); 1116 qemu_iovec_concat(&hd_qiov, qiov, bytes_done, sinfo.bytes_avail); 1117 1118 /* check the payload block state */ 1119 switch (s->bat[sinfo.bat_idx] & VHDX_BAT_STATE_BIT_MASK) { 1120 case PAYLOAD_BLOCK_NOT_PRESENT: /* fall through */ 1121 case PAYLOAD_BLOCK_UNDEFINED: 1122 case PAYLOAD_BLOCK_UNMAPPED: 1123 case PAYLOAD_BLOCK_UNMAPPED_v095: 1124 case PAYLOAD_BLOCK_ZERO: 1125 /* return zero */ 1126 qemu_iovec_memset(&hd_qiov, 0, 0, sinfo.bytes_avail); 1127 break; 1128 case PAYLOAD_BLOCK_FULLY_PRESENT: 1129 qemu_co_mutex_unlock(&s->lock); 1130 ret = bdrv_co_preadv(bs->file, sinfo.file_offset, 1131 sinfo.sectors_avail * BDRV_SECTOR_SIZE, 1132 &hd_qiov, 0); 1133 qemu_co_mutex_lock(&s->lock); 1134 if (ret < 0) { 1135 goto exit; 1136 } 1137 break; 1138 case PAYLOAD_BLOCK_PARTIALLY_PRESENT: 1139 /* we don't yet support difference files, fall through 1140 * to error */ 1141 default: 1142 ret = -EIO; 1143 goto exit; 1144 break; 1145 } 1146 nb_sectors -= sinfo.sectors_avail; 1147 sector_num += sinfo.sectors_avail; 1148 bytes_done += sinfo.bytes_avail; 1149 } 1150 } 1151 ret = 0; 1152 exit: 1153 qemu_co_mutex_unlock(&s->lock); 1154 qemu_iovec_destroy(&hd_qiov); 1155 return ret; 1156 } 1157 1158 /* 1159 * Allocate a new payload block at the end of the file. 1160 * 1161 * Allocation will happen at 1MB alignment inside the file 1162 * 1163 * Returns the file offset start of the new payload block 1164 */ 1165 static int vhdx_allocate_block(BlockDriverState *bs, BDRVVHDXState *s, 1166 uint64_t *new_offset) 1167 { 1168 int64_t current_len; 1169 1170 current_len = bdrv_getlength(bs->file->bs); 1171 if (current_len < 0) { 1172 return current_len; 1173 } 1174 1175 *new_offset = current_len; 1176 1177 /* per the spec, the address for a block is in units of 1MB */ 1178 *new_offset = ROUND_UP(*new_offset, 1024 * 1024); 1179 if (*new_offset > INT64_MAX) { 1180 return -EINVAL; 1181 } 1182 1183 return bdrv_truncate(bs->file, *new_offset + s->block_size, 1184 PREALLOC_MODE_OFF, NULL); 1185 } 1186 1187 /* 1188 * Update the BAT table entry with the new file offset, and the new entry 1189 * state */ 1190 static void vhdx_update_bat_table_entry(BlockDriverState *bs, BDRVVHDXState *s, 1191 VHDXSectorInfo *sinfo, 1192 uint64_t *bat_entry_le, 1193 uint64_t *bat_offset, int state) 1194 { 1195 /* The BAT entry is a uint64, with 44 bits for the file offset in units of 1196 * 1MB, and 3 bits for the block state. */ 1197 if ((state == PAYLOAD_BLOCK_ZERO) || 1198 (state == PAYLOAD_BLOCK_UNDEFINED) || 1199 (state == PAYLOAD_BLOCK_NOT_PRESENT) || 1200 (state == PAYLOAD_BLOCK_UNMAPPED)) { 1201 s->bat[sinfo->bat_idx] = 0; /* For PAYLOAD_BLOCK_ZERO, the 1202 FileOffsetMB field is denoted as 1203 'reserved' in the v1.0 spec. If it is 1204 non-zero, MS Hyper-V will fail to read 1205 the disk image */ 1206 } else { 1207 s->bat[sinfo->bat_idx] = sinfo->file_offset; 1208 } 1209 1210 s->bat[sinfo->bat_idx] |= state & VHDX_BAT_STATE_BIT_MASK; 1211 1212 *bat_entry_le = cpu_to_le64(s->bat[sinfo->bat_idx]); 1213 *bat_offset = s->bat_offset + sinfo->bat_idx * sizeof(VHDXBatEntry); 1214 1215 } 1216 1217 /* Per the spec, on the first write of guest-visible data to the file the 1218 * data write guid must be updated in the header */ 1219 int vhdx_user_visible_write(BlockDriverState *bs, BDRVVHDXState *s) 1220 { 1221 int ret = 0; 1222 if (s->first_visible_write) { 1223 s->first_visible_write = false; 1224 ret = vhdx_update_headers(bs, s, true, NULL); 1225 } 1226 return ret; 1227 } 1228 1229 static coroutine_fn int vhdx_co_writev(BlockDriverState *bs, int64_t sector_num, 1230 int nb_sectors, QEMUIOVector *qiov, 1231 int flags) 1232 { 1233 int ret = -ENOTSUP; 1234 BDRVVHDXState *s = bs->opaque; 1235 VHDXSectorInfo sinfo; 1236 uint64_t bytes_done = 0; 1237 uint64_t bat_entry = 0; 1238 uint64_t bat_entry_offset = 0; 1239 QEMUIOVector hd_qiov; 1240 struct iovec iov1 = { 0 }; 1241 struct iovec iov2 = { 0 }; 1242 int sectors_to_write; 1243 int bat_state; 1244 uint64_t bat_prior_offset = 0; 1245 bool bat_update = false; 1246 1247 assert(!flags); 1248 qemu_iovec_init(&hd_qiov, qiov->niov); 1249 1250 qemu_co_mutex_lock(&s->lock); 1251 1252 ret = vhdx_user_visible_write(bs, s); 1253 if (ret < 0) { 1254 goto exit; 1255 } 1256 1257 while (nb_sectors > 0) { 1258 bool use_zero_buffers = false; 1259 bat_update = false; 1260 if (s->params.data_bits & VHDX_PARAMS_HAS_PARENT) { 1261 /* not supported yet */ 1262 ret = -ENOTSUP; 1263 goto exit; 1264 } else { 1265 vhdx_block_translate(s, sector_num, nb_sectors, &sinfo); 1266 sectors_to_write = sinfo.sectors_avail; 1267 1268 qemu_iovec_reset(&hd_qiov); 1269 /* check the payload block state */ 1270 bat_state = s->bat[sinfo.bat_idx] & VHDX_BAT_STATE_BIT_MASK; 1271 switch (bat_state) { 1272 case PAYLOAD_BLOCK_ZERO: 1273 /* in this case, we need to preserve zero writes for 1274 * data that is not part of this write, so we must pad 1275 * the rest of the buffer to zeroes */ 1276 1277 /* if we are on a posix system with ftruncate() that extends 1278 * a file, then it is zero-filled for us. On Win32, the raw 1279 * layer uses SetFilePointer and SetFileEnd, which does not 1280 * zero fill AFAIK */ 1281 1282 /* Queue another write of zero buffers if the underlying file 1283 * does not zero-fill on file extension */ 1284 1285 if (bdrv_has_zero_init(bs->file->bs) == 0) { 1286 use_zero_buffers = true; 1287 1288 /* zero fill the front, if any */ 1289 if (sinfo.block_offset) { 1290 iov1.iov_len = sinfo.block_offset; 1291 iov1.iov_base = qemu_blockalign(bs, iov1.iov_len); 1292 memset(iov1.iov_base, 0, iov1.iov_len); 1293 qemu_iovec_concat_iov(&hd_qiov, &iov1, 1, 0, 1294 iov1.iov_len); 1295 sectors_to_write += iov1.iov_len >> BDRV_SECTOR_BITS; 1296 } 1297 1298 /* our actual data */ 1299 qemu_iovec_concat(&hd_qiov, qiov, bytes_done, 1300 sinfo.bytes_avail); 1301 1302 /* zero fill the back, if any */ 1303 if ((sinfo.bytes_avail - sinfo.block_offset) < 1304 s->block_size) { 1305 iov2.iov_len = s->block_size - 1306 (sinfo.bytes_avail + sinfo.block_offset); 1307 iov2.iov_base = qemu_blockalign(bs, iov2.iov_len); 1308 memset(iov2.iov_base, 0, iov2.iov_len); 1309 qemu_iovec_concat_iov(&hd_qiov, &iov2, 1, 0, 1310 iov2.iov_len); 1311 sectors_to_write += iov2.iov_len >> BDRV_SECTOR_BITS; 1312 } 1313 } 1314 /* fall through */ 1315 case PAYLOAD_BLOCK_NOT_PRESENT: /* fall through */ 1316 case PAYLOAD_BLOCK_UNMAPPED: 1317 case PAYLOAD_BLOCK_UNMAPPED_v095: 1318 case PAYLOAD_BLOCK_UNDEFINED: 1319 bat_prior_offset = sinfo.file_offset; 1320 ret = vhdx_allocate_block(bs, s, &sinfo.file_offset); 1321 if (ret < 0) { 1322 goto exit; 1323 } 1324 /* once we support differencing files, this may also be 1325 * partially present */ 1326 /* update block state to the newly specified state */ 1327 vhdx_update_bat_table_entry(bs, s, &sinfo, &bat_entry, 1328 &bat_entry_offset, 1329 PAYLOAD_BLOCK_FULLY_PRESENT); 1330 bat_update = true; 1331 /* since we just allocated a block, file_offset is the 1332 * beginning of the payload block. It needs to be the 1333 * write address, which includes the offset into the block */ 1334 if (!use_zero_buffers) { 1335 sinfo.file_offset += sinfo.block_offset; 1336 } 1337 /* fall through */ 1338 case PAYLOAD_BLOCK_FULLY_PRESENT: 1339 /* if the file offset address is in the header zone, 1340 * there is a problem */ 1341 if (sinfo.file_offset < (1024 * 1024)) { 1342 ret = -EFAULT; 1343 goto error_bat_restore; 1344 } 1345 1346 if (!use_zero_buffers) { 1347 qemu_iovec_concat(&hd_qiov, qiov, bytes_done, 1348 sinfo.bytes_avail); 1349 } 1350 /* block exists, so we can just overwrite it */ 1351 qemu_co_mutex_unlock(&s->lock); 1352 ret = bdrv_co_pwritev(bs->file, sinfo.file_offset, 1353 sectors_to_write * BDRV_SECTOR_SIZE, 1354 &hd_qiov, 0); 1355 qemu_co_mutex_lock(&s->lock); 1356 if (ret < 0) { 1357 goto error_bat_restore; 1358 } 1359 break; 1360 case PAYLOAD_BLOCK_PARTIALLY_PRESENT: 1361 /* we don't yet support difference files, fall through 1362 * to error */ 1363 default: 1364 ret = -EIO; 1365 goto exit; 1366 break; 1367 } 1368 1369 if (bat_update) { 1370 /* this will update the BAT entry into the log journal, and 1371 * then flush the log journal out to disk */ 1372 ret = vhdx_log_write_and_flush(bs, s, &bat_entry, 1373 sizeof(VHDXBatEntry), 1374 bat_entry_offset); 1375 if (ret < 0) { 1376 goto exit; 1377 } 1378 } 1379 1380 nb_sectors -= sinfo.sectors_avail; 1381 sector_num += sinfo.sectors_avail; 1382 bytes_done += sinfo.bytes_avail; 1383 1384 } 1385 } 1386 1387 goto exit; 1388 1389 error_bat_restore: 1390 if (bat_update) { 1391 /* keep metadata in sync, and restore the bat entry state 1392 * if error. */ 1393 sinfo.file_offset = bat_prior_offset; 1394 vhdx_update_bat_table_entry(bs, s, &sinfo, &bat_entry, 1395 &bat_entry_offset, bat_state); 1396 } 1397 exit: 1398 qemu_vfree(iov1.iov_base); 1399 qemu_vfree(iov2.iov_base); 1400 qemu_co_mutex_unlock(&s->lock); 1401 qemu_iovec_destroy(&hd_qiov); 1402 return ret; 1403 } 1404 1405 1406 1407 /* 1408 * Create VHDX Headers 1409 * 1410 * There are 2 headers, and the highest sequence number will represent 1411 * the active header 1412 */ 1413 static int vhdx_create_new_headers(BlockBackend *blk, uint64_t image_size, 1414 uint32_t log_size) 1415 { 1416 BlockDriverState *bs = blk_bs(blk); 1417 BdrvChild *child; 1418 int ret = 0; 1419 VHDXHeader *hdr = NULL; 1420 1421 hdr = g_new0(VHDXHeader, 1); 1422 1423 hdr->signature = VHDX_HEADER_SIGNATURE; 1424 hdr->sequence_number = g_random_int(); 1425 hdr->log_version = 0; 1426 hdr->version = 1; 1427 hdr->log_length = log_size; 1428 hdr->log_offset = VHDX_HEADER_SECTION_END; 1429 vhdx_guid_generate(&hdr->file_write_guid); 1430 vhdx_guid_generate(&hdr->data_write_guid); 1431 1432 /* XXX Ugly way to get blk->root, but that's a feature, not a bug. This 1433 * hack makes it obvious that vhdx_write_header() bypasses the BlockBackend 1434 * here, which it really shouldn't be doing. */ 1435 child = QLIST_FIRST(&bs->parents); 1436 assert(!QLIST_NEXT(child, next_parent)); 1437 1438 ret = vhdx_write_header(child, hdr, VHDX_HEADER1_OFFSET, false); 1439 if (ret < 0) { 1440 goto exit; 1441 } 1442 hdr->sequence_number++; 1443 ret = vhdx_write_header(child, hdr, VHDX_HEADER2_OFFSET, false); 1444 if (ret < 0) { 1445 goto exit; 1446 } 1447 1448 exit: 1449 g_free(hdr); 1450 return ret; 1451 } 1452 1453 #define VHDX_METADATA_ENTRY_BUFFER_SIZE \ 1454 (sizeof(VHDXFileParameters) +\ 1455 sizeof(VHDXVirtualDiskSize) +\ 1456 sizeof(VHDXPage83Data) +\ 1457 sizeof(VHDXVirtualDiskLogicalSectorSize) +\ 1458 sizeof(VHDXVirtualDiskPhysicalSectorSize)) 1459 1460 /* 1461 * Create the Metadata entries. 1462 * 1463 * For more details on the entries, see section 3.5 (pg 29) in the 1464 * VHDX 1.00 specification. 1465 * 1466 * We support 5 metadata entries (all required by spec): 1467 * File Parameters, 1468 * Virtual Disk Size, 1469 * Page 83 Data, 1470 * Logical Sector Size, 1471 * Physical Sector Size 1472 * 1473 * The first 64KB of the Metadata section is reserved for the metadata 1474 * header and entries; beyond that, the metadata items themselves reside. 1475 */ 1476 static int vhdx_create_new_metadata(BlockBackend *blk, 1477 uint64_t image_size, 1478 uint32_t block_size, 1479 uint32_t sector_size, 1480 uint64_t metadata_offset, 1481 VHDXImageType type) 1482 { 1483 int ret = 0; 1484 uint32_t offset = 0; 1485 void *buffer = NULL; 1486 void *entry_buffer; 1487 VHDXMetadataTableHeader *md_table; 1488 VHDXMetadataTableEntry *md_table_entry; 1489 1490 /* Metadata entries */ 1491 VHDXFileParameters *mt_file_params; 1492 VHDXVirtualDiskSize *mt_virtual_size; 1493 VHDXPage83Data *mt_page83; 1494 VHDXVirtualDiskLogicalSectorSize *mt_log_sector_size; 1495 VHDXVirtualDiskPhysicalSectorSize *mt_phys_sector_size; 1496 1497 entry_buffer = g_malloc0(VHDX_METADATA_ENTRY_BUFFER_SIZE); 1498 1499 mt_file_params = entry_buffer; 1500 offset += sizeof(VHDXFileParameters); 1501 mt_virtual_size = entry_buffer + offset; 1502 offset += sizeof(VHDXVirtualDiskSize); 1503 mt_page83 = entry_buffer + offset; 1504 offset += sizeof(VHDXPage83Data); 1505 mt_log_sector_size = entry_buffer + offset; 1506 offset += sizeof(VHDXVirtualDiskLogicalSectorSize); 1507 mt_phys_sector_size = entry_buffer + offset; 1508 1509 mt_file_params->block_size = cpu_to_le32(block_size); 1510 if (type == VHDX_TYPE_FIXED) { 1511 mt_file_params->data_bits |= VHDX_PARAMS_LEAVE_BLOCKS_ALLOCED; 1512 cpu_to_le32s(&mt_file_params->data_bits); 1513 } 1514 1515 vhdx_guid_generate(&mt_page83->page_83_data); 1516 cpu_to_leguids(&mt_page83->page_83_data); 1517 mt_virtual_size->virtual_disk_size = cpu_to_le64(image_size); 1518 mt_log_sector_size->logical_sector_size = cpu_to_le32(sector_size); 1519 mt_phys_sector_size->physical_sector_size = cpu_to_le32(sector_size); 1520 1521 buffer = g_malloc0(VHDX_HEADER_BLOCK_SIZE); 1522 md_table = buffer; 1523 1524 md_table->signature = VHDX_METADATA_SIGNATURE; 1525 md_table->entry_count = 5; 1526 vhdx_metadata_header_le_export(md_table); 1527 1528 1529 /* This will reference beyond the reserved table portion */ 1530 offset = 64 * KiB; 1531 1532 md_table_entry = buffer + sizeof(VHDXMetadataTableHeader); 1533 1534 md_table_entry[0].item_id = file_param_guid; 1535 md_table_entry[0].offset = offset; 1536 md_table_entry[0].length = sizeof(VHDXFileParameters); 1537 md_table_entry[0].data_bits |= VHDX_META_FLAGS_IS_REQUIRED; 1538 offset += md_table_entry[0].length; 1539 vhdx_metadata_entry_le_export(&md_table_entry[0]); 1540 1541 md_table_entry[1].item_id = virtual_size_guid; 1542 md_table_entry[1].offset = offset; 1543 md_table_entry[1].length = sizeof(VHDXVirtualDiskSize); 1544 md_table_entry[1].data_bits |= VHDX_META_FLAGS_IS_REQUIRED | 1545 VHDX_META_FLAGS_IS_VIRTUAL_DISK; 1546 offset += md_table_entry[1].length; 1547 vhdx_metadata_entry_le_export(&md_table_entry[1]); 1548 1549 md_table_entry[2].item_id = page83_guid; 1550 md_table_entry[2].offset = offset; 1551 md_table_entry[2].length = sizeof(VHDXPage83Data); 1552 md_table_entry[2].data_bits |= VHDX_META_FLAGS_IS_REQUIRED | 1553 VHDX_META_FLAGS_IS_VIRTUAL_DISK; 1554 offset += md_table_entry[2].length; 1555 vhdx_metadata_entry_le_export(&md_table_entry[2]); 1556 1557 md_table_entry[3].item_id = logical_sector_guid; 1558 md_table_entry[3].offset = offset; 1559 md_table_entry[3].length = sizeof(VHDXVirtualDiskLogicalSectorSize); 1560 md_table_entry[3].data_bits |= VHDX_META_FLAGS_IS_REQUIRED | 1561 VHDX_META_FLAGS_IS_VIRTUAL_DISK; 1562 offset += md_table_entry[3].length; 1563 vhdx_metadata_entry_le_export(&md_table_entry[3]); 1564 1565 md_table_entry[4].item_id = phys_sector_guid; 1566 md_table_entry[4].offset = offset; 1567 md_table_entry[4].length = sizeof(VHDXVirtualDiskPhysicalSectorSize); 1568 md_table_entry[4].data_bits |= VHDX_META_FLAGS_IS_REQUIRED | 1569 VHDX_META_FLAGS_IS_VIRTUAL_DISK; 1570 vhdx_metadata_entry_le_export(&md_table_entry[4]); 1571 1572 ret = blk_pwrite(blk, metadata_offset, buffer, VHDX_HEADER_BLOCK_SIZE, 0); 1573 if (ret < 0) { 1574 goto exit; 1575 } 1576 1577 ret = blk_pwrite(blk, metadata_offset + (64 * KiB), entry_buffer, 1578 VHDX_METADATA_ENTRY_BUFFER_SIZE, 0); 1579 if (ret < 0) { 1580 goto exit; 1581 } 1582 1583 1584 exit: 1585 g_free(buffer); 1586 g_free(entry_buffer); 1587 return ret; 1588 } 1589 1590 /* This create the actual BAT itself. We currently only support 1591 * 'Dynamic' and 'Fixed' image types. 1592 * 1593 * Dynamic images: default state of the BAT is all zeroes. 1594 * 1595 * Fixed images: default state of the BAT is fully populated, with 1596 * file offsets and state PAYLOAD_BLOCK_FULLY_PRESENT. 1597 */ 1598 static int vhdx_create_bat(BlockBackend *blk, BDRVVHDXState *s, 1599 uint64_t image_size, VHDXImageType type, 1600 bool use_zero_blocks, uint64_t file_offset, 1601 uint32_t length, Error **errp) 1602 { 1603 int ret = 0; 1604 uint64_t data_file_offset; 1605 uint64_t total_sectors = 0; 1606 uint64_t sector_num = 0; 1607 uint64_t unused; 1608 int block_state; 1609 VHDXSectorInfo sinfo; 1610 1611 assert(s->bat == NULL); 1612 1613 /* this gives a data start after BAT/bitmap entries, and well 1614 * past any metadata entries (with a 4 MB buffer for future 1615 * expansion */ 1616 data_file_offset = file_offset + length + 5 * MiB; 1617 total_sectors = image_size >> s->logical_sector_size_bits; 1618 1619 if (type == VHDX_TYPE_DYNAMIC) { 1620 /* All zeroes, so we can just extend the file - the end of the BAT 1621 * is the furthest thing we have written yet */ 1622 ret = blk_truncate(blk, data_file_offset, PREALLOC_MODE_OFF, errp); 1623 if (ret < 0) { 1624 goto exit; 1625 } 1626 } else if (type == VHDX_TYPE_FIXED) { 1627 ret = blk_truncate(blk, data_file_offset + image_size, 1628 PREALLOC_MODE_OFF, errp); 1629 if (ret < 0) { 1630 goto exit; 1631 } 1632 } else { 1633 error_setg(errp, "Unsupported image type"); 1634 ret = -ENOTSUP; 1635 goto exit; 1636 } 1637 1638 if (type == VHDX_TYPE_FIXED || 1639 use_zero_blocks || 1640 bdrv_has_zero_init(blk_bs(blk)) == 0) { 1641 /* for a fixed file, the default BAT entry is not zero */ 1642 s->bat = g_try_malloc0(length); 1643 if (length && s->bat == NULL) { 1644 error_setg(errp, "Failed to allocate memory for the BAT"); 1645 ret = -ENOMEM; 1646 goto exit; 1647 } 1648 block_state = type == VHDX_TYPE_FIXED ? PAYLOAD_BLOCK_FULLY_PRESENT : 1649 PAYLOAD_BLOCK_NOT_PRESENT; 1650 block_state = use_zero_blocks ? PAYLOAD_BLOCK_ZERO : block_state; 1651 /* fill the BAT by emulating sector writes of sectors_per_block size */ 1652 while (sector_num < total_sectors) { 1653 vhdx_block_translate(s, sector_num, s->sectors_per_block, &sinfo); 1654 sinfo.file_offset = data_file_offset + 1655 (sector_num << s->logical_sector_size_bits); 1656 sinfo.file_offset = ROUND_UP(sinfo.file_offset, MiB); 1657 vhdx_update_bat_table_entry(blk_bs(blk), s, &sinfo, &unused, &unused, 1658 block_state); 1659 cpu_to_le64s(&s->bat[sinfo.bat_idx]); 1660 sector_num += s->sectors_per_block; 1661 } 1662 ret = blk_pwrite(blk, file_offset, s->bat, length, 0); 1663 if (ret < 0) { 1664 error_setg_errno(errp, -ret, "Failed to write the BAT"); 1665 goto exit; 1666 } 1667 } 1668 1669 1670 1671 exit: 1672 g_free(s->bat); 1673 return ret; 1674 } 1675 1676 /* Creates the region table header, and region table entries. 1677 * There are 2 supported region table entries: BAT, and Metadata/ 1678 * 1679 * As the calculations for the BAT region table are also needed 1680 * to create the BAT itself, we will also cause the BAT to be 1681 * created. 1682 */ 1683 static int vhdx_create_new_region_table(BlockBackend *blk, 1684 uint64_t image_size, 1685 uint32_t block_size, 1686 uint32_t sector_size, 1687 uint32_t log_size, 1688 bool use_zero_blocks, 1689 VHDXImageType type, 1690 uint64_t *metadata_offset, 1691 Error **errp) 1692 { 1693 int ret = 0; 1694 uint32_t offset = 0; 1695 void *buffer = NULL; 1696 uint64_t bat_file_offset; 1697 uint32_t bat_length; 1698 BDRVVHDXState *s = NULL; 1699 VHDXRegionTableHeader *region_table; 1700 VHDXRegionTableEntry *rt_bat; 1701 VHDXRegionTableEntry *rt_metadata; 1702 1703 assert(metadata_offset != NULL); 1704 1705 /* Populate enough of the BDRVVHDXState to be able to use the 1706 * pre-existing BAT calculation, translation, and update functions */ 1707 s = g_new0(BDRVVHDXState, 1); 1708 1709 s->chunk_ratio = (VHDX_MAX_SECTORS_PER_BLOCK) * 1710 (uint64_t) sector_size / (uint64_t) block_size; 1711 1712 s->sectors_per_block = block_size / sector_size; 1713 s->virtual_disk_size = image_size; 1714 s->block_size = block_size; 1715 s->logical_sector_size = sector_size; 1716 1717 vhdx_set_shift_bits(s); 1718 1719 vhdx_calc_bat_entries(s); 1720 1721 /* At this point the VHDX state is populated enough for creation */ 1722 1723 /* a single buffer is used so we can calculate the checksum over the 1724 * entire 64KB block */ 1725 buffer = g_malloc0(VHDX_HEADER_BLOCK_SIZE); 1726 region_table = buffer; 1727 offset += sizeof(VHDXRegionTableHeader); 1728 rt_bat = buffer + offset; 1729 offset += sizeof(VHDXRegionTableEntry); 1730 rt_metadata = buffer + offset; 1731 1732 region_table->signature = VHDX_REGION_SIGNATURE; 1733 region_table->entry_count = 2; /* BAT and Metadata */ 1734 1735 rt_bat->guid = bat_guid; 1736 rt_bat->length = ROUND_UP(s->bat_entries * sizeof(VHDXBatEntry), MiB); 1737 rt_bat->file_offset = ROUND_UP(VHDX_HEADER_SECTION_END + log_size, MiB); 1738 s->bat_offset = rt_bat->file_offset; 1739 1740 rt_metadata->guid = metadata_guid; 1741 rt_metadata->file_offset = ROUND_UP(rt_bat->file_offset + rt_bat->length, 1742 MiB); 1743 rt_metadata->length = 1 * MiB; /* min size, and more than enough */ 1744 *metadata_offset = rt_metadata->file_offset; 1745 1746 bat_file_offset = rt_bat->file_offset; 1747 bat_length = rt_bat->length; 1748 1749 vhdx_region_header_le_export(region_table); 1750 vhdx_region_entry_le_export(rt_bat); 1751 vhdx_region_entry_le_export(rt_metadata); 1752 1753 vhdx_update_checksum(buffer, VHDX_HEADER_BLOCK_SIZE, 1754 offsetof(VHDXRegionTableHeader, checksum)); 1755 1756 1757 /* The region table gives us the data we need to create the BAT, 1758 * so do that now */ 1759 ret = vhdx_create_bat(blk, s, image_size, type, use_zero_blocks, 1760 bat_file_offset, bat_length, errp); 1761 if (ret < 0) { 1762 goto exit; 1763 } 1764 1765 /* Now write out the region headers to disk */ 1766 ret = blk_pwrite(blk, VHDX_REGION_TABLE_OFFSET, buffer, 1767 VHDX_HEADER_BLOCK_SIZE, 0); 1768 if (ret < 0) { 1769 error_setg_errno(errp, -ret, "Failed to write first region table"); 1770 goto exit; 1771 } 1772 1773 ret = blk_pwrite(blk, VHDX_REGION_TABLE2_OFFSET, buffer, 1774 VHDX_HEADER_BLOCK_SIZE, 0); 1775 if (ret < 0) { 1776 error_setg_errno(errp, -ret, "Failed to write second region table"); 1777 goto exit; 1778 } 1779 1780 exit: 1781 g_free(s); 1782 g_free(buffer); 1783 return ret; 1784 } 1785 1786 /* We need to create the following elements: 1787 * 1788 * .-----------------------------------------------------------------. 1789 * | (A) | (B) | (C) | (D) | (E) | 1790 * | File ID | Header1 | Header 2 | Region Tbl 1 | Region Tbl 2 | 1791 * | | | | | | 1792 * .-----------------------------------------------------------------. 1793 * 0 64KB 128KB 192KB 256KB 320KB 1794 * 1795 * 1796 * .---- ~ ----------- ~ ------------ ~ ---------------- ~ -----------. 1797 * | (F) | (G) | (H) | | 1798 * | Journal Log | BAT / Bitmap | Metadata | .... data ...... | 1799 * | | | | | 1800 * .---- ~ ----------- ~ ------------ ~ ---------------- ~ -----------. 1801 * 1MB 1802 */ 1803 static int coroutine_fn vhdx_co_create(BlockdevCreateOptions *opts, 1804 Error **errp) 1805 { 1806 BlockdevCreateOptionsVhdx *vhdx_opts; 1807 BlockBackend *blk = NULL; 1808 BlockDriverState *bs = NULL; 1809 1810 int ret = 0; 1811 uint64_t image_size; 1812 uint32_t log_size; 1813 uint32_t block_size; 1814 uint64_t signature; 1815 uint64_t metadata_offset; 1816 bool use_zero_blocks = false; 1817 1818 gunichar2 *creator = NULL; 1819 glong creator_items; 1820 VHDXImageType image_type; 1821 1822 assert(opts->driver == BLOCKDEV_DRIVER_VHDX); 1823 vhdx_opts = &opts->u.vhdx; 1824 1825 /* Validate options and set default values */ 1826 image_size = vhdx_opts->size; 1827 if (image_size > VHDX_MAX_IMAGE_SIZE) { 1828 error_setg(errp, "Image size too large; max of 64TB"); 1829 return -EINVAL; 1830 } 1831 1832 if (!vhdx_opts->has_log_size) { 1833 log_size = DEFAULT_LOG_SIZE; 1834 } else { 1835 if (vhdx_opts->log_size > UINT32_MAX) { 1836 error_setg(errp, "Log size must be smaller than 4 GB"); 1837 return -EINVAL; 1838 } 1839 log_size = vhdx_opts->log_size; 1840 } 1841 if (log_size < MiB || (log_size % MiB) != 0) { 1842 error_setg(errp, "Log size must be a multiple of 1 MB"); 1843 return -EINVAL; 1844 } 1845 1846 if (!vhdx_opts->has_block_state_zero) { 1847 use_zero_blocks = true; 1848 } else { 1849 use_zero_blocks = vhdx_opts->block_state_zero; 1850 } 1851 1852 if (!vhdx_opts->has_subformat) { 1853 vhdx_opts->subformat = BLOCKDEV_VHDX_SUBFORMAT_DYNAMIC; 1854 } 1855 1856 switch (vhdx_opts->subformat) { 1857 case BLOCKDEV_VHDX_SUBFORMAT_DYNAMIC: 1858 image_type = VHDX_TYPE_DYNAMIC; 1859 break; 1860 case BLOCKDEV_VHDX_SUBFORMAT_FIXED: 1861 image_type = VHDX_TYPE_FIXED; 1862 break; 1863 default: 1864 g_assert_not_reached(); 1865 } 1866 1867 /* These are pretty arbitrary, and mainly designed to keep the BAT 1868 * size reasonable to load into RAM */ 1869 if (vhdx_opts->has_block_size) { 1870 block_size = vhdx_opts->block_size; 1871 } else { 1872 if (image_size > 32 * TiB) { 1873 block_size = 64 * MiB; 1874 } else if (image_size > (uint64_t) 100 * GiB) { 1875 block_size = 32 * MiB; 1876 } else if (image_size > 1 * GiB) { 1877 block_size = 16 * MiB; 1878 } else { 1879 block_size = 8 * MiB; 1880 } 1881 } 1882 1883 if (block_size < MiB || (block_size % MiB) != 0) { 1884 error_setg(errp, "Block size must be a multiple of 1 MB"); 1885 return -EINVAL; 1886 } 1887 if (!is_power_of_2(block_size)) { 1888 error_setg(errp, "Block size must be a power of two"); 1889 return -EINVAL; 1890 } 1891 if (block_size > VHDX_BLOCK_SIZE_MAX) { 1892 error_setg(errp, "Block size must not exceed %d", VHDX_BLOCK_SIZE_MAX); 1893 return -EINVAL; 1894 } 1895 1896 /* Create BlockBackend to write to the image */ 1897 bs = bdrv_open_blockdev_ref(vhdx_opts->file, errp); 1898 if (bs == NULL) { 1899 return -EIO; 1900 } 1901 1902 blk = blk_new(BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL); 1903 ret = blk_insert_bs(blk, bs, errp); 1904 if (ret < 0) { 1905 goto delete_and_exit; 1906 } 1907 blk_set_allow_write_beyond_eof(blk, true); 1908 1909 /* Create (A) */ 1910 1911 /* The creator field is optional, but may be useful for 1912 * debugging / diagnostics */ 1913 creator = g_utf8_to_utf16("QEMU v" QEMU_VERSION, -1, NULL, 1914 &creator_items, NULL); 1915 signature = cpu_to_le64(VHDX_FILE_SIGNATURE); 1916 ret = blk_pwrite(blk, VHDX_FILE_ID_OFFSET, &signature, sizeof(signature), 1917 0); 1918 if (ret < 0) { 1919 error_setg_errno(errp, -ret, "Failed to write file signature"); 1920 goto delete_and_exit; 1921 } 1922 if (creator) { 1923 ret = blk_pwrite(blk, VHDX_FILE_ID_OFFSET + sizeof(signature), 1924 creator, creator_items * sizeof(gunichar2), 0); 1925 if (ret < 0) { 1926 error_setg_errno(errp, -ret, "Failed to write creator field"); 1927 goto delete_and_exit; 1928 } 1929 } 1930 1931 1932 /* Creates (B),(C) */ 1933 ret = vhdx_create_new_headers(blk, image_size, log_size); 1934 if (ret < 0) { 1935 error_setg_errno(errp, -ret, "Failed to write image headers"); 1936 goto delete_and_exit; 1937 } 1938 1939 /* Creates (D),(E),(G) explicitly. (F) created as by-product */ 1940 ret = vhdx_create_new_region_table(blk, image_size, block_size, 512, 1941 log_size, use_zero_blocks, image_type, 1942 &metadata_offset, errp); 1943 if (ret < 0) { 1944 goto delete_and_exit; 1945 } 1946 1947 /* Creates (H) */ 1948 ret = vhdx_create_new_metadata(blk, image_size, block_size, 512, 1949 metadata_offset, image_type); 1950 if (ret < 0) { 1951 error_setg_errno(errp, -ret, "Failed to initialize metadata"); 1952 goto delete_and_exit; 1953 } 1954 1955 ret = 0; 1956 delete_and_exit: 1957 blk_unref(blk); 1958 bdrv_unref(bs); 1959 g_free(creator); 1960 return ret; 1961 } 1962 1963 static int coroutine_fn vhdx_co_create_opts(const char *filename, 1964 QemuOpts *opts, 1965 Error **errp) 1966 { 1967 BlockdevCreateOptions *create_options = NULL; 1968 QDict *qdict; 1969 Visitor *v; 1970 BlockDriverState *bs = NULL; 1971 Error *local_err = NULL; 1972 int ret; 1973 1974 static const QDictRenames opt_renames[] = { 1975 { VHDX_BLOCK_OPT_LOG_SIZE, "log-size" }, 1976 { VHDX_BLOCK_OPT_BLOCK_SIZE, "block-size" }, 1977 { VHDX_BLOCK_OPT_ZERO, "block-state-zero" }, 1978 { NULL, NULL }, 1979 }; 1980 1981 /* Parse options and convert legacy syntax */ 1982 qdict = qemu_opts_to_qdict_filtered(opts, NULL, &vhdx_create_opts, true); 1983 1984 if (!qdict_rename_keys(qdict, opt_renames, errp)) { 1985 ret = -EINVAL; 1986 goto fail; 1987 } 1988 1989 /* Create and open the file (protocol layer) */ 1990 ret = bdrv_create_file(filename, opts, &local_err); 1991 if (ret < 0) { 1992 error_propagate(errp, local_err); 1993 goto fail; 1994 } 1995 1996 bs = bdrv_open(filename, NULL, NULL, 1997 BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL, errp); 1998 if (bs == NULL) { 1999 ret = -EIO; 2000 goto fail; 2001 } 2002 2003 /* Now get the QAPI type BlockdevCreateOptions */ 2004 qdict_put_str(qdict, "driver", "vhdx"); 2005 qdict_put_str(qdict, "file", bs->node_name); 2006 2007 v = qobject_input_visitor_new_flat_confused(qdict, errp); 2008 if (!v) { 2009 ret = -EINVAL; 2010 goto fail; 2011 } 2012 2013 visit_type_BlockdevCreateOptions(v, NULL, &create_options, &local_err); 2014 visit_free(v); 2015 2016 if (local_err) { 2017 error_propagate(errp, local_err); 2018 ret = -EINVAL; 2019 goto fail; 2020 } 2021 2022 /* Silently round up sizes: 2023 * The image size is rounded to 512 bytes. Make the block and log size 2024 * close to what was specified, but must be at least 1MB, and a multiple of 2025 * 1 MB. Also respect VHDX_BLOCK_SIZE_MAX for block sizes. block_size = 0 2026 * means auto, which is represented by a missing key in QAPI. */ 2027 assert(create_options->driver == BLOCKDEV_DRIVER_VHDX); 2028 create_options->u.vhdx.size = 2029 ROUND_UP(create_options->u.vhdx.size, BDRV_SECTOR_SIZE); 2030 2031 if (create_options->u.vhdx.has_log_size) { 2032 create_options->u.vhdx.log_size = 2033 ROUND_UP(create_options->u.vhdx.log_size, MiB); 2034 } 2035 if (create_options->u.vhdx.has_block_size) { 2036 create_options->u.vhdx.block_size = 2037 ROUND_UP(create_options->u.vhdx.block_size, MiB); 2038 2039 if (create_options->u.vhdx.block_size == 0) { 2040 create_options->u.vhdx.has_block_size = false; 2041 } 2042 if (create_options->u.vhdx.block_size > VHDX_BLOCK_SIZE_MAX) { 2043 create_options->u.vhdx.block_size = VHDX_BLOCK_SIZE_MAX; 2044 } 2045 } 2046 2047 /* Create the vhdx image (format layer) */ 2048 ret = vhdx_co_create(create_options, errp); 2049 2050 fail: 2051 qobject_unref(qdict); 2052 bdrv_unref(bs); 2053 qapi_free_BlockdevCreateOptions(create_options); 2054 return ret; 2055 } 2056 2057 /* If opened r/w, the VHDX driver will automatically replay the log, 2058 * if one is present, inside the vhdx_open() call. 2059 * 2060 * If qemu-img check -r all is called, the image is automatically opened 2061 * r/w and any log has already been replayed, so there is nothing (currently) 2062 * for us to do here 2063 */ 2064 static int coroutine_fn vhdx_co_check(BlockDriverState *bs, 2065 BdrvCheckResult *result, 2066 BdrvCheckMode fix) 2067 { 2068 BDRVVHDXState *s = bs->opaque; 2069 2070 if (s->log_replayed_on_open) { 2071 result->corruptions_fixed++; 2072 } 2073 return 0; 2074 } 2075 2076 static QemuOptsList vhdx_create_opts = { 2077 .name = "vhdx-create-opts", 2078 .head = QTAILQ_HEAD_INITIALIZER(vhdx_create_opts.head), 2079 .desc = { 2080 { 2081 .name = BLOCK_OPT_SIZE, 2082 .type = QEMU_OPT_SIZE, 2083 .help = "Virtual disk size; max of 64TB." 2084 }, 2085 { 2086 .name = VHDX_BLOCK_OPT_LOG_SIZE, 2087 .type = QEMU_OPT_SIZE, 2088 .def_value_str = stringify(DEFAULT_LOG_SIZE), 2089 .help = "Log size; min 1MB." 2090 }, 2091 { 2092 .name = VHDX_BLOCK_OPT_BLOCK_SIZE, 2093 .type = QEMU_OPT_SIZE, 2094 .def_value_str = stringify(0), 2095 .help = "Block Size; min 1MB, max 256MB. " \ 2096 "0 means auto-calculate based on image size." 2097 }, 2098 { 2099 .name = BLOCK_OPT_SUBFMT, 2100 .type = QEMU_OPT_STRING, 2101 .help = "VHDX format type, can be either 'dynamic' or 'fixed'. "\ 2102 "Default is 'dynamic'." 2103 }, 2104 { 2105 .name = VHDX_BLOCK_OPT_ZERO, 2106 .type = QEMU_OPT_BOOL, 2107 .help = "Force use of payload blocks of type 'ZERO'. "\ 2108 "Non-standard, but default. Do not set to 'off' when "\ 2109 "using 'qemu-img convert' with subformat=dynamic." 2110 }, 2111 { NULL } 2112 } 2113 }; 2114 2115 static BlockDriver bdrv_vhdx = { 2116 .format_name = "vhdx", 2117 .instance_size = sizeof(BDRVVHDXState), 2118 .bdrv_probe = vhdx_probe, 2119 .bdrv_open = vhdx_open, 2120 .bdrv_close = vhdx_close, 2121 .bdrv_reopen_prepare = vhdx_reopen_prepare, 2122 .bdrv_child_perm = bdrv_format_default_perms, 2123 .bdrv_co_readv = vhdx_co_readv, 2124 .bdrv_co_writev = vhdx_co_writev, 2125 .bdrv_co_create = vhdx_co_create, 2126 .bdrv_co_create_opts = vhdx_co_create_opts, 2127 .bdrv_get_info = vhdx_get_info, 2128 .bdrv_co_check = vhdx_co_check, 2129 .bdrv_has_zero_init = bdrv_has_zero_init_1, 2130 2131 .create_opts = &vhdx_create_opts, 2132 }; 2133 2134 static void bdrv_vhdx_init(void) 2135 { 2136 bdrv_register(&bdrv_vhdx); 2137 } 2138 2139 block_init(bdrv_vhdx_init); 2140