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