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 "qemu/module.h" 22 #include "qemu/crc32c.h" 23 #include "block/vhdx.h" 24 #include "migration/migration.h" 25 26 #include <uuid/uuid.h> 27 #include <glib.h> 28 29 /* Options for VHDX creation */ 30 31 #define VHDX_BLOCK_OPT_LOG_SIZE "log_size" 32 #define VHDX_BLOCK_OPT_BLOCK_SIZE "block_size" 33 #define VHDX_BLOCK_OPT_ZERO "block_state_zero" 34 35 typedef enum VHDXImageType { 36 VHDX_TYPE_DYNAMIC = 0, 37 VHDX_TYPE_FIXED, 38 VHDX_TYPE_DIFFERENCING, /* Currently unsupported */ 39 } VHDXImageType; 40 41 /* Several metadata and region table data entries are identified by 42 * guids in a MS-specific GUID format. */ 43 44 45 /* ------- Known Region Table GUIDs ---------------------- */ 46 static const MSGUID bat_guid = { .data1 = 0x2dc27766, 47 .data2 = 0xf623, 48 .data3 = 0x4200, 49 .data4 = { 0x9d, 0x64, 0x11, 0x5e, 50 0x9b, 0xfd, 0x4a, 0x08} }; 51 52 static const MSGUID metadata_guid = { .data1 = 0x8b7ca206, 53 .data2 = 0x4790, 54 .data3 = 0x4b9a, 55 .data4 = { 0xb8, 0xfe, 0x57, 0x5f, 56 0x05, 0x0f, 0x88, 0x6e} }; 57 58 59 60 /* ------- Known Metadata Entry GUIDs ---------------------- */ 61 static const MSGUID file_param_guid = { .data1 = 0xcaa16737, 62 .data2 = 0xfa36, 63 .data3 = 0x4d43, 64 .data4 = { 0xb3, 0xb6, 0x33, 0xf0, 65 0xaa, 0x44, 0xe7, 0x6b} }; 66 67 static const MSGUID virtual_size_guid = { .data1 = 0x2FA54224, 68 .data2 = 0xcd1b, 69 .data3 = 0x4876, 70 .data4 = { 0xb2, 0x11, 0x5d, 0xbe, 71 0xd8, 0x3b, 0xf4, 0xb8} }; 72 73 static const MSGUID page83_guid = { .data1 = 0xbeca12ab, 74 .data2 = 0xb2e6, 75 .data3 = 0x4523, 76 .data4 = { 0x93, 0xef, 0xc3, 0x09, 77 0xe0, 0x00, 0xc7, 0x46} }; 78 79 80 static const MSGUID phys_sector_guid = { .data1 = 0xcda348c7, 81 .data2 = 0x445d, 82 .data3 = 0x4471, 83 .data4 = { 0x9c, 0xc9, 0xe9, 0x88, 84 0x52, 0x51, 0xc5, 0x56} }; 85 86 static const MSGUID parent_locator_guid = { .data1 = 0xa8d35f2d, 87 .data2 = 0xb30b, 88 .data3 = 0x454d, 89 .data4 = { 0xab, 0xf7, 0xd3, 90 0xd8, 0x48, 0x34, 91 0xab, 0x0c} }; 92 93 static const MSGUID logical_sector_guid = { .data1 = 0x8141bf1d, 94 .data2 = 0xa96f, 95 .data3 = 0x4709, 96 .data4 = { 0xba, 0x47, 0xf2, 97 0x33, 0xa8, 0xfa, 98 0xab, 0x5f} }; 99 100 /* Each parent type must have a valid GUID; this is for parent images 101 * of type 'VHDX'. If we were to allow e.g. a QCOW2 parent, we would 102 * need to make up our own QCOW2 GUID type */ 103 static const MSGUID parent_vhdx_guid __attribute__((unused)) 104 = { .data1 = 0xb04aefb7, 105 .data2 = 0xd19e, 106 .data3 = 0x4a81, 107 .data4 = { 0xb7, 0x89, 0x25, 0xb8, 108 0xe9, 0x44, 0x59, 0x13} }; 109 110 111 #define META_FILE_PARAMETER_PRESENT 0x01 112 #define META_VIRTUAL_DISK_SIZE_PRESENT 0x02 113 #define META_PAGE_83_PRESENT 0x04 114 #define META_LOGICAL_SECTOR_SIZE_PRESENT 0x08 115 #define META_PHYS_SECTOR_SIZE_PRESENT 0x10 116 #define META_PARENT_LOCATOR_PRESENT 0x20 117 118 #define META_ALL_PRESENT \ 119 (META_FILE_PARAMETER_PRESENT | META_VIRTUAL_DISK_SIZE_PRESENT | \ 120 META_PAGE_83_PRESENT | META_LOGICAL_SECTOR_SIZE_PRESENT | \ 121 META_PHYS_SECTOR_SIZE_PRESENT) 122 123 124 typedef struct VHDXSectorInfo { 125 uint32_t bat_idx; /* BAT entry index */ 126 uint32_t sectors_avail; /* sectors available in payload block */ 127 uint32_t bytes_left; /* bytes left in the block after data to r/w */ 128 uint32_t bytes_avail; /* bytes available in payload block */ 129 uint64_t file_offset; /* absolute offset in bytes, in file */ 130 uint64_t block_offset; /* block offset, in bytes */ 131 } VHDXSectorInfo; 132 133 /* Calculates new checksum. 134 * 135 * Zero is substituted during crc calculation for the original crc field 136 * crc_offset: byte offset in buf of the buffer crc 137 * buf: buffer pointer 138 * size: size of buffer (must be > crc_offset+4) 139 * 140 * Note: The buffer should have all multi-byte data in little-endian format, 141 * and the resulting checksum is in little endian format. 142 */ 143 uint32_t vhdx_update_checksum(uint8_t *buf, size_t size, int crc_offset) 144 { 145 uint32_t crc; 146 147 assert(buf != NULL); 148 assert(size > (crc_offset + sizeof(crc))); 149 150 memset(buf + crc_offset, 0, sizeof(crc)); 151 crc = crc32c(0xffffffff, buf, size); 152 cpu_to_le32s(&crc); 153 memcpy(buf + crc_offset, &crc, sizeof(crc)); 154 155 return crc; 156 } 157 158 uint32_t vhdx_checksum_calc(uint32_t crc, uint8_t *buf, size_t size, 159 int crc_offset) 160 { 161 uint32_t crc_new; 162 uint32_t crc_orig; 163 assert(buf != NULL); 164 165 if (crc_offset > 0) { 166 memcpy(&crc_orig, buf + crc_offset, sizeof(crc_orig)); 167 memset(buf + crc_offset, 0, sizeof(crc_orig)); 168 } 169 170 crc_new = crc32c(crc, buf, size); 171 if (crc_offset > 0) { 172 memcpy(buf + crc_offset, &crc_orig, sizeof(crc_orig)); 173 } 174 175 return crc_new; 176 } 177 178 /* Validates the checksum of the buffer, with an in-place CRC. 179 * 180 * Zero is substituted during crc calculation for the original crc field, 181 * and the crc field is restored afterwards. But the buffer will be modifed 182 * during the calculation, so this may not be not suitable for multi-threaded 183 * use. 184 * 185 * crc_offset: byte offset in buf of the buffer crc 186 * buf: buffer pointer 187 * size: size of buffer (must be > crc_offset+4) 188 * 189 * returns true if checksum is valid, false otherwise 190 */ 191 bool vhdx_checksum_is_valid(uint8_t *buf, size_t size, int crc_offset) 192 { 193 uint32_t crc_orig; 194 uint32_t crc; 195 196 assert(buf != NULL); 197 assert(size > (crc_offset + 4)); 198 199 memcpy(&crc_orig, buf + crc_offset, sizeof(crc_orig)); 200 crc_orig = le32_to_cpu(crc_orig); 201 202 crc = vhdx_checksum_calc(0xffffffff, buf, size, crc_offset); 203 204 return crc == crc_orig; 205 } 206 207 208 /* 209 * This generates a UUID that is compliant with the MS GUIDs used 210 * in the VHDX spec (and elsewhere). 211 */ 212 void vhdx_guid_generate(MSGUID *guid) 213 { 214 uuid_t uuid; 215 assert(guid != NULL); 216 217 uuid_generate(uuid); 218 memcpy(guid, uuid, sizeof(MSGUID)); 219 } 220 221 /* Check for region overlaps inside the VHDX image */ 222 static int vhdx_region_check(BDRVVHDXState *s, uint64_t start, uint64_t length) 223 { 224 int ret = 0; 225 uint64_t end; 226 VHDXRegionEntry *r; 227 228 end = start + length; 229 QLIST_FOREACH(r, &s->regions, entries) { 230 if (!((start >= r->end) || (end <= r->start))) { 231 ret = -EINVAL; 232 goto exit; 233 } 234 } 235 236 exit: 237 return ret; 238 } 239 240 /* Register a region for future checks */ 241 static void vhdx_region_register(BDRVVHDXState *s, 242 uint64_t start, uint64_t length) 243 { 244 VHDXRegionEntry *r; 245 246 r = g_malloc0(sizeof(*r)); 247 248 r->start = start; 249 r->end = start + length; 250 251 QLIST_INSERT_HEAD(&s->regions, r, entries); 252 } 253 254 /* Free all registered regions */ 255 static void vhdx_region_unregister_all(BDRVVHDXState *s) 256 { 257 VHDXRegionEntry *r, *r_next; 258 259 QLIST_FOREACH_SAFE(r, &s->regions, entries, r_next) { 260 QLIST_REMOVE(r, entries); 261 g_free(r); 262 } 263 } 264 265 static void vhdx_set_shift_bits(BDRVVHDXState *s) 266 { 267 s->logical_sector_size_bits = 31 - clz32(s->logical_sector_size); 268 s->sectors_per_block_bits = 31 - clz32(s->sectors_per_block); 269 s->chunk_ratio_bits = 63 - clz64(s->chunk_ratio); 270 s->block_size_bits = 31 - clz32(s->block_size); 271 } 272 273 /* 274 * Per the MS VHDX Specification, for every VHDX file: 275 * - The header section is fixed size - 1 MB 276 * - The header section is always the first "object" 277 * - The first 64KB of the header is the File Identifier 278 * - The first uint64 (8 bytes) is the VHDX Signature ("vhdxfile") 279 * - The following 512 bytes constitute a UTF-16 string identifiying the 280 * software that created the file, and is optional and diagnostic only. 281 * 282 * Therefore, we probe by looking for the vhdxfile signature "vhdxfile" 283 */ 284 static int vhdx_probe(const uint8_t *buf, int buf_size, const char *filename) 285 { 286 if (buf_size >= 8 && !memcmp(buf, "vhdxfile", 8)) { 287 return 100; 288 } 289 return 0; 290 } 291 292 /* 293 * Writes the header to the specified offset. 294 * 295 * This will optionally read in buffer data from disk (otherwise zero-fill), 296 * and then update the header checksum. Header is converted to proper 297 * endianness before being written to the specified file offset 298 */ 299 static int vhdx_write_header(BlockDriverState *bs_file, VHDXHeader *hdr, 300 uint64_t offset, bool read) 301 { 302 uint8_t *buffer = NULL; 303 int ret; 304 VHDXHeader *header_le; 305 306 assert(bs_file != NULL); 307 assert(hdr != NULL); 308 309 /* the header checksum is not over just the packed size of VHDXHeader, 310 * but rather over the entire 'reserved' range for the header, which is 311 * 4KB (VHDX_HEADER_SIZE). */ 312 313 buffer = qemu_blockalign(bs_file, VHDX_HEADER_SIZE); 314 if (read) { 315 /* if true, we can't assume the extra reserved bytes are 0 */ 316 ret = bdrv_pread(bs_file, offset, buffer, VHDX_HEADER_SIZE); 317 if (ret < 0) { 318 goto exit; 319 } 320 } else { 321 memset(buffer, 0, VHDX_HEADER_SIZE); 322 } 323 324 /* overwrite the actual VHDXHeader portion */ 325 header_le = (VHDXHeader *)buffer; 326 memcpy(header_le, hdr, sizeof(VHDXHeader)); 327 vhdx_header_le_export(hdr, header_le); 328 vhdx_update_checksum(buffer, VHDX_HEADER_SIZE, 329 offsetof(VHDXHeader, checksum)); 330 ret = bdrv_pwrite_sync(bs_file, offset, header_le, sizeof(VHDXHeader)); 331 332 exit: 333 qemu_vfree(buffer); 334 return ret; 335 } 336 337 /* Update the VHDX headers 338 * 339 * This follows the VHDX spec procedures for header updates. 340 * 341 * - non-current header is updated with largest sequence number 342 */ 343 static int vhdx_update_header(BlockDriverState *bs, BDRVVHDXState *s, 344 bool generate_data_write_guid, MSGUID *log_guid) 345 { 346 int ret = 0; 347 int hdr_idx = 0; 348 uint64_t header_offset = VHDX_HEADER1_OFFSET; 349 350 VHDXHeader *active_header; 351 VHDXHeader *inactive_header; 352 353 /* operate on the non-current header */ 354 if (s->curr_header == 0) { 355 hdr_idx = 1; 356 header_offset = VHDX_HEADER2_OFFSET; 357 } 358 359 active_header = s->headers[s->curr_header]; 360 inactive_header = s->headers[hdr_idx]; 361 362 inactive_header->sequence_number = active_header->sequence_number + 1; 363 364 /* a new file guid must be generated before any file write, including 365 * headers */ 366 inactive_header->file_write_guid = s->session_guid; 367 368 /* a new data guid only needs to be generated before any guest-visible 369 * writes (i.e. something observable via virtual disk read) */ 370 if (generate_data_write_guid) { 371 vhdx_guid_generate(&inactive_header->data_write_guid); 372 } 373 374 /* update the log guid if present */ 375 if (log_guid) { 376 inactive_header->log_guid = *log_guid; 377 } 378 379 ret = vhdx_write_header(bs->file->bs, inactive_header, header_offset, true); 380 if (ret < 0) { 381 goto exit; 382 } 383 s->curr_header = hdr_idx; 384 385 exit: 386 return ret; 387 } 388 389 /* 390 * The VHDX spec calls for header updates to be performed twice, so that both 391 * the current and non-current header have valid info 392 */ 393 int vhdx_update_headers(BlockDriverState *bs, BDRVVHDXState *s, 394 bool generate_data_write_guid, MSGUID *log_guid) 395 { 396 int ret; 397 398 ret = vhdx_update_header(bs, s, generate_data_write_guid, log_guid); 399 if (ret < 0) { 400 return ret; 401 } 402 ret = vhdx_update_header(bs, s, generate_data_write_guid, log_guid); 403 return ret; 404 } 405 406 /* opens the specified header block from the VHDX file header section */ 407 static void vhdx_parse_header(BlockDriverState *bs, BDRVVHDXState *s, 408 Error **errp) 409 { 410 int ret; 411 VHDXHeader *header1; 412 VHDXHeader *header2; 413 bool h1_valid = false; 414 bool h2_valid = false; 415 uint64_t h1_seq = 0; 416 uint64_t h2_seq = 0; 417 uint8_t *buffer; 418 419 /* header1 & header2 are freed in vhdx_close() */ 420 header1 = qemu_blockalign(bs, sizeof(VHDXHeader)); 421 header2 = qemu_blockalign(bs, sizeof(VHDXHeader)); 422 423 buffer = qemu_blockalign(bs, VHDX_HEADER_SIZE); 424 425 s->headers[0] = header1; 426 s->headers[1] = header2; 427 428 /* We have to read the whole VHDX_HEADER_SIZE instead of 429 * sizeof(VHDXHeader), because the checksum is over the whole 430 * region */ 431 ret = bdrv_pread(bs->file->bs, VHDX_HEADER1_OFFSET, buffer, 432 VHDX_HEADER_SIZE); 433 if (ret < 0) { 434 goto fail; 435 } 436 /* copy over just the relevant portion that we need */ 437 memcpy(header1, buffer, sizeof(VHDXHeader)); 438 439 if (vhdx_checksum_is_valid(buffer, VHDX_HEADER_SIZE, 4)) { 440 vhdx_header_le_import(header1); 441 if (header1->signature == VHDX_HEADER_SIGNATURE && 442 header1->version == 1) { 443 h1_seq = header1->sequence_number; 444 h1_valid = true; 445 } 446 } 447 448 ret = bdrv_pread(bs->file->bs, VHDX_HEADER2_OFFSET, buffer, 449 VHDX_HEADER_SIZE); 450 if (ret < 0) { 451 goto fail; 452 } 453 /* copy over just the relevant portion that we need */ 454 memcpy(header2, buffer, sizeof(VHDXHeader)); 455 456 if (vhdx_checksum_is_valid(buffer, VHDX_HEADER_SIZE, 4)) { 457 vhdx_header_le_import(header2); 458 if (header2->signature == VHDX_HEADER_SIGNATURE && 459 header2->version == 1) { 460 h2_seq = header2->sequence_number; 461 h2_valid = true; 462 } 463 } 464 465 /* If there is only 1 valid header (or no valid headers), we 466 * don't care what the sequence numbers are */ 467 if (h1_valid && !h2_valid) { 468 s->curr_header = 0; 469 } else if (!h1_valid && h2_valid) { 470 s->curr_header = 1; 471 } else if (!h1_valid && !h2_valid) { 472 goto fail; 473 } else { 474 /* If both headers are valid, then we choose the active one by the 475 * highest sequence number. If the sequence numbers are equal, that is 476 * invalid */ 477 if (h1_seq > h2_seq) { 478 s->curr_header = 0; 479 } else if (h2_seq > h1_seq) { 480 s->curr_header = 1; 481 } else { 482 /* The Microsoft Disk2VHD tool will create 2 identical 483 * headers, with identical sequence numbers. If the headers are 484 * identical, don't consider the file corrupt */ 485 if (!memcmp(header1, header2, sizeof(VHDXHeader))) { 486 s->curr_header = 0; 487 } else { 488 goto fail; 489 } 490 } 491 } 492 493 vhdx_region_register(s, s->headers[s->curr_header]->log_offset, 494 s->headers[s->curr_header]->log_length); 495 goto exit; 496 497 fail: 498 error_setg_errno(errp, -ret, "No valid VHDX header found"); 499 qemu_vfree(header1); 500 qemu_vfree(header2); 501 s->headers[0] = NULL; 502 s->headers[1] = NULL; 503 exit: 504 qemu_vfree(buffer); 505 } 506 507 508 static int vhdx_open_region_tables(BlockDriverState *bs, BDRVVHDXState *s) 509 { 510 int ret = 0; 511 uint8_t *buffer; 512 int offset = 0; 513 VHDXRegionTableEntry rt_entry; 514 uint32_t i; 515 bool bat_rt_found = false; 516 bool metadata_rt_found = false; 517 518 /* We have to read the whole 64KB block, because the crc32 is over the 519 * whole block */ 520 buffer = qemu_blockalign(bs, VHDX_HEADER_BLOCK_SIZE); 521 522 ret = bdrv_pread(bs->file->bs, VHDX_REGION_TABLE_OFFSET, buffer, 523 VHDX_HEADER_BLOCK_SIZE); 524 if (ret < 0) { 525 goto fail; 526 } 527 memcpy(&s->rt, buffer, sizeof(s->rt)); 528 offset += sizeof(s->rt); 529 530 if (!vhdx_checksum_is_valid(buffer, VHDX_HEADER_BLOCK_SIZE, 4)) { 531 ret = -EINVAL; 532 goto fail; 533 } 534 535 vhdx_region_header_le_import(&s->rt); 536 537 if (s->rt.signature != VHDX_REGION_SIGNATURE) { 538 ret = -EINVAL; 539 goto fail; 540 } 541 542 543 /* Per spec, maximum region table entry count is 2047 */ 544 if (s->rt.entry_count > 2047) { 545 ret = -EINVAL; 546 goto fail; 547 } 548 549 for (i = 0; i < s->rt.entry_count; i++) { 550 memcpy(&rt_entry, buffer + offset, sizeof(rt_entry)); 551 offset += sizeof(rt_entry); 552 553 vhdx_region_entry_le_import(&rt_entry); 554 555 /* check for region overlap between these entries, and any 556 * other memory regions in the file */ 557 ret = vhdx_region_check(s, rt_entry.file_offset, rt_entry.length); 558 if (ret < 0) { 559 goto fail; 560 } 561 562 vhdx_region_register(s, rt_entry.file_offset, rt_entry.length); 563 564 /* see if we recognize the entry */ 565 if (guid_eq(rt_entry.guid, bat_guid)) { 566 /* must be unique; if we have already found it this is invalid */ 567 if (bat_rt_found) { 568 ret = -EINVAL; 569 goto fail; 570 } 571 bat_rt_found = true; 572 s->bat_rt = rt_entry; 573 continue; 574 } 575 576 if (guid_eq(rt_entry.guid, metadata_guid)) { 577 /* must be unique; if we have already found it this is invalid */ 578 if (metadata_rt_found) { 579 ret = -EINVAL; 580 goto fail; 581 } 582 metadata_rt_found = true; 583 s->metadata_rt = rt_entry; 584 continue; 585 } 586 587 if (rt_entry.data_bits & VHDX_REGION_ENTRY_REQUIRED) { 588 /* cannot read vhdx file - required region table entry that 589 * we do not understand. per spec, we must fail to open */ 590 ret = -ENOTSUP; 591 goto fail; 592 } 593 } 594 595 if (!bat_rt_found || !metadata_rt_found) { 596 ret = -EINVAL; 597 goto fail; 598 } 599 600 ret = 0; 601 602 fail: 603 qemu_vfree(buffer); 604 return ret; 605 } 606 607 608 609 /* Metadata initial parser 610 * 611 * This loads all the metadata entry fields. This may cause additional 612 * fields to be processed (e.g. parent locator, etc..). 613 * 614 * There are 5 Metadata items that are always required: 615 * - File Parameters (block size, has a parent) 616 * - Virtual Disk Size (size, in bytes, of the virtual drive) 617 * - Page 83 Data (scsi page 83 guid) 618 * - Logical Sector Size (logical sector size in bytes, either 512 or 619 * 4096. We only support 512 currently) 620 * - Physical Sector Size (512 or 4096) 621 * 622 * Also, if the File Parameters indicate this is a differencing file, 623 * we must also look for the Parent Locator metadata item. 624 */ 625 static int vhdx_parse_metadata(BlockDriverState *bs, BDRVVHDXState *s) 626 { 627 int ret = 0; 628 uint8_t *buffer; 629 int offset = 0; 630 uint32_t i = 0; 631 VHDXMetadataTableEntry md_entry; 632 633 buffer = qemu_blockalign(bs, VHDX_METADATA_TABLE_MAX_SIZE); 634 635 ret = bdrv_pread(bs->file->bs, s->metadata_rt.file_offset, buffer, 636 VHDX_METADATA_TABLE_MAX_SIZE); 637 if (ret < 0) { 638 goto exit; 639 } 640 memcpy(&s->metadata_hdr, buffer, sizeof(s->metadata_hdr)); 641 offset += sizeof(s->metadata_hdr); 642 643 vhdx_metadata_header_le_import(&s->metadata_hdr); 644 645 if (s->metadata_hdr.signature != VHDX_METADATA_SIGNATURE) { 646 ret = -EINVAL; 647 goto exit; 648 } 649 650 s->metadata_entries.present = 0; 651 652 if ((s->metadata_hdr.entry_count * sizeof(md_entry)) > 653 (VHDX_METADATA_TABLE_MAX_SIZE - offset)) { 654 ret = -EINVAL; 655 goto exit; 656 } 657 658 for (i = 0; i < s->metadata_hdr.entry_count; i++) { 659 memcpy(&md_entry, buffer + offset, sizeof(md_entry)); 660 offset += sizeof(md_entry); 661 662 vhdx_metadata_entry_le_import(&md_entry); 663 664 if (guid_eq(md_entry.item_id, file_param_guid)) { 665 if (s->metadata_entries.present & META_FILE_PARAMETER_PRESENT) { 666 ret = -EINVAL; 667 goto exit; 668 } 669 s->metadata_entries.file_parameters_entry = md_entry; 670 s->metadata_entries.present |= META_FILE_PARAMETER_PRESENT; 671 continue; 672 } 673 674 if (guid_eq(md_entry.item_id, virtual_size_guid)) { 675 if (s->metadata_entries.present & META_VIRTUAL_DISK_SIZE_PRESENT) { 676 ret = -EINVAL; 677 goto exit; 678 } 679 s->metadata_entries.virtual_disk_size_entry = md_entry; 680 s->metadata_entries.present |= META_VIRTUAL_DISK_SIZE_PRESENT; 681 continue; 682 } 683 684 if (guid_eq(md_entry.item_id, page83_guid)) { 685 if (s->metadata_entries.present & META_PAGE_83_PRESENT) { 686 ret = -EINVAL; 687 goto exit; 688 } 689 s->metadata_entries.page83_data_entry = md_entry; 690 s->metadata_entries.present |= META_PAGE_83_PRESENT; 691 continue; 692 } 693 694 if (guid_eq(md_entry.item_id, logical_sector_guid)) { 695 if (s->metadata_entries.present & 696 META_LOGICAL_SECTOR_SIZE_PRESENT) { 697 ret = -EINVAL; 698 goto exit; 699 } 700 s->metadata_entries.logical_sector_size_entry = md_entry; 701 s->metadata_entries.present |= META_LOGICAL_SECTOR_SIZE_PRESENT; 702 continue; 703 } 704 705 if (guid_eq(md_entry.item_id, phys_sector_guid)) { 706 if (s->metadata_entries.present & META_PHYS_SECTOR_SIZE_PRESENT) { 707 ret = -EINVAL; 708 goto exit; 709 } 710 s->metadata_entries.phys_sector_size_entry = md_entry; 711 s->metadata_entries.present |= META_PHYS_SECTOR_SIZE_PRESENT; 712 continue; 713 } 714 715 if (guid_eq(md_entry.item_id, parent_locator_guid)) { 716 if (s->metadata_entries.present & META_PARENT_LOCATOR_PRESENT) { 717 ret = -EINVAL; 718 goto exit; 719 } 720 s->metadata_entries.parent_locator_entry = md_entry; 721 s->metadata_entries.present |= META_PARENT_LOCATOR_PRESENT; 722 continue; 723 } 724 725 if (md_entry.data_bits & VHDX_META_FLAGS_IS_REQUIRED) { 726 /* cannot read vhdx file - required region table entry that 727 * we do not understand. per spec, we must fail to open */ 728 ret = -ENOTSUP; 729 goto exit; 730 } 731 } 732 733 if (s->metadata_entries.present != META_ALL_PRESENT) { 734 ret = -ENOTSUP; 735 goto exit; 736 } 737 738 ret = bdrv_pread(bs->file->bs, 739 s->metadata_entries.file_parameters_entry.offset 740 + s->metadata_rt.file_offset, 741 &s->params, 742 sizeof(s->params)); 743 744 if (ret < 0) { 745 goto exit; 746 } 747 748 le32_to_cpus(&s->params.block_size); 749 le32_to_cpus(&s->params.data_bits); 750 751 752 /* We now have the file parameters, so we can tell if this is a 753 * differencing file (i.e.. has_parent), is dynamic or fixed 754 * sized (leave_blocks_allocated), and the block size */ 755 756 /* The parent locator required iff the file parameters has_parent set */ 757 if (s->params.data_bits & VHDX_PARAMS_HAS_PARENT) { 758 if (s->metadata_entries.present & META_PARENT_LOCATOR_PRESENT) { 759 /* TODO: parse parent locator fields */ 760 ret = -ENOTSUP; /* temp, until differencing files are supported */ 761 goto exit; 762 } else { 763 /* if has_parent is set, but there is not parent locator present, 764 * then that is an invalid combination */ 765 ret = -EINVAL; 766 goto exit; 767 } 768 } 769 770 /* determine virtual disk size, logical sector size, 771 * and phys sector size */ 772 773 ret = bdrv_pread(bs->file->bs, 774 s->metadata_entries.virtual_disk_size_entry.offset 775 + s->metadata_rt.file_offset, 776 &s->virtual_disk_size, 777 sizeof(uint64_t)); 778 if (ret < 0) { 779 goto exit; 780 } 781 ret = bdrv_pread(bs->file->bs, 782 s->metadata_entries.logical_sector_size_entry.offset 783 + s->metadata_rt.file_offset, 784 &s->logical_sector_size, 785 sizeof(uint32_t)); 786 if (ret < 0) { 787 goto exit; 788 } 789 ret = bdrv_pread(bs->file->bs, 790 s->metadata_entries.phys_sector_size_entry.offset 791 + s->metadata_rt.file_offset, 792 &s->physical_sector_size, 793 sizeof(uint32_t)); 794 if (ret < 0) { 795 goto exit; 796 } 797 798 le64_to_cpus(&s->virtual_disk_size); 799 le32_to_cpus(&s->logical_sector_size); 800 le32_to_cpus(&s->physical_sector_size); 801 802 if (s->params.block_size < VHDX_BLOCK_SIZE_MIN || 803 s->params.block_size > VHDX_BLOCK_SIZE_MAX) { 804 ret = -EINVAL; 805 goto exit; 806 } 807 808 /* only 2 supported sector sizes */ 809 if (s->logical_sector_size != 512 && s->logical_sector_size != 4096) { 810 ret = -EINVAL; 811 goto exit; 812 } 813 814 /* Both block_size and sector_size are guaranteed powers of 2, below. 815 Due to range checks above, s->sectors_per_block can never be < 256 */ 816 s->sectors_per_block = s->params.block_size / s->logical_sector_size; 817 s->chunk_ratio = (VHDX_MAX_SECTORS_PER_BLOCK) * 818 (uint64_t)s->logical_sector_size / 819 (uint64_t)s->params.block_size; 820 821 /* These values are ones we will want to use for division / multiplication 822 * later on, and they are all guaranteed (per the spec) to be powers of 2, 823 * so we can take advantage of that for shift operations during 824 * reads/writes */ 825 if (s->logical_sector_size & (s->logical_sector_size - 1)) { 826 ret = -EINVAL; 827 goto exit; 828 } 829 if (s->sectors_per_block & (s->sectors_per_block - 1)) { 830 ret = -EINVAL; 831 goto exit; 832 } 833 if (s->chunk_ratio & (s->chunk_ratio - 1)) { 834 ret = -EINVAL; 835 goto exit; 836 } 837 s->block_size = s->params.block_size; 838 if (s->block_size & (s->block_size - 1)) { 839 ret = -EINVAL; 840 goto exit; 841 } 842 843 vhdx_set_shift_bits(s); 844 845 ret = 0; 846 847 exit: 848 qemu_vfree(buffer); 849 return ret; 850 } 851 852 /* 853 * Calculate the number of BAT entries, including sector 854 * bitmap entries. 855 */ 856 static void vhdx_calc_bat_entries(BDRVVHDXState *s) 857 { 858 uint32_t data_blocks_cnt, bitmap_blocks_cnt; 859 860 data_blocks_cnt = s->virtual_disk_size >> s->block_size_bits; 861 if (s->virtual_disk_size - (data_blocks_cnt << s->block_size_bits)) { 862 data_blocks_cnt++; 863 } 864 bitmap_blocks_cnt = data_blocks_cnt >> s->chunk_ratio_bits; 865 if (data_blocks_cnt - (bitmap_blocks_cnt << s->chunk_ratio_bits)) { 866 bitmap_blocks_cnt++; 867 } 868 869 if (s->parent_entries) { 870 s->bat_entries = bitmap_blocks_cnt * (s->chunk_ratio + 1); 871 } else { 872 s->bat_entries = data_blocks_cnt + 873 ((data_blocks_cnt - 1) >> s->chunk_ratio_bits); 874 } 875 876 } 877 878 static void vhdx_close(BlockDriverState *bs) 879 { 880 BDRVVHDXState *s = bs->opaque; 881 qemu_vfree(s->headers[0]); 882 s->headers[0] = NULL; 883 qemu_vfree(s->headers[1]); 884 s->headers[1] = NULL; 885 qemu_vfree(s->bat); 886 s->bat = NULL; 887 qemu_vfree(s->parent_entries); 888 s->parent_entries = NULL; 889 migrate_del_blocker(s->migration_blocker); 890 error_free(s->migration_blocker); 891 qemu_vfree(s->log.hdr); 892 s->log.hdr = NULL; 893 vhdx_region_unregister_all(s); 894 } 895 896 static int vhdx_open(BlockDriverState *bs, QDict *options, int flags, 897 Error **errp) 898 { 899 BDRVVHDXState *s = bs->opaque; 900 int ret = 0; 901 uint32_t i; 902 uint64_t signature; 903 Error *local_err = NULL; 904 905 s->bat = NULL; 906 s->first_visible_write = true; 907 908 qemu_co_mutex_init(&s->lock); 909 QLIST_INIT(&s->regions); 910 911 /* validate the file signature */ 912 ret = bdrv_pread(bs->file->bs, 0, &signature, sizeof(uint64_t)); 913 if (ret < 0) { 914 goto fail; 915 } 916 if (memcmp(&signature, "vhdxfile", 8)) { 917 ret = -EINVAL; 918 goto fail; 919 } 920 921 /* This is used for any header updates, for the file_write_guid. 922 * The spec dictates that a new value should be used for the first 923 * header update */ 924 vhdx_guid_generate(&s->session_guid); 925 926 vhdx_parse_header(bs, s, &local_err); 927 if (local_err != NULL) { 928 error_propagate(errp, local_err); 929 ret = -EINVAL; 930 goto fail; 931 } 932 933 ret = vhdx_parse_log(bs, s, &s->log_replayed_on_open, errp); 934 if (ret < 0) { 935 goto fail; 936 } 937 938 ret = vhdx_open_region_tables(bs, s); 939 if (ret < 0) { 940 goto fail; 941 } 942 943 ret = vhdx_parse_metadata(bs, s); 944 if (ret < 0) { 945 goto fail; 946 } 947 948 s->block_size = s->params.block_size; 949 950 /* the VHDX spec dictates that virtual_disk_size is always a multiple of 951 * logical_sector_size */ 952 bs->total_sectors = s->virtual_disk_size >> s->logical_sector_size_bits; 953 954 vhdx_calc_bat_entries(s); 955 956 s->bat_offset = s->bat_rt.file_offset; 957 958 if (s->bat_entries > s->bat_rt.length / sizeof(VHDXBatEntry)) { 959 /* BAT allocation is not large enough for all entries */ 960 ret = -EINVAL; 961 goto fail; 962 } 963 964 /* s->bat is freed in vhdx_close() */ 965 s->bat = qemu_try_blockalign(bs->file->bs, s->bat_rt.length); 966 if (s->bat == NULL) { 967 ret = -ENOMEM; 968 goto fail; 969 } 970 971 ret = bdrv_pread(bs->file->bs, s->bat_offset, s->bat, s->bat_rt.length); 972 if (ret < 0) { 973 goto fail; 974 } 975 976 uint64_t payblocks = s->chunk_ratio; 977 /* endian convert, and verify populated BAT field file offsets against 978 * region table and log entries */ 979 for (i = 0; i < s->bat_entries; i++) { 980 le64_to_cpus(&s->bat[i]); 981 if (payblocks--) { 982 /* payload bat entries */ 983 if ((s->bat[i] & VHDX_BAT_STATE_BIT_MASK) == 984 PAYLOAD_BLOCK_FULLY_PRESENT) { 985 ret = vhdx_region_check(s, s->bat[i] & VHDX_BAT_FILE_OFF_MASK, 986 s->block_size); 987 if (ret < 0) { 988 goto fail; 989 } 990 } 991 } else { 992 payblocks = s->chunk_ratio; 993 /* Once differencing files are supported, verify sector bitmap 994 * blocks here */ 995 } 996 } 997 998 if (flags & BDRV_O_RDWR) { 999 ret = vhdx_update_headers(bs, s, false, NULL); 1000 if (ret < 0) { 1001 goto fail; 1002 } 1003 } 1004 1005 /* TODO: differencing files */ 1006 1007 /* Disable migration when VHDX images are used */ 1008 error_setg(&s->migration_blocker, "The vhdx format used by node '%s' " 1009 "does not support live migration", 1010 bdrv_get_device_or_node_name(bs)); 1011 migrate_add_blocker(s->migration_blocker); 1012 1013 return 0; 1014 fail: 1015 vhdx_close(bs); 1016 return ret; 1017 } 1018 1019 static int vhdx_reopen_prepare(BDRVReopenState *state, 1020 BlockReopenQueue *queue, Error **errp) 1021 { 1022 return 0; 1023 } 1024 1025 1026 /* 1027 * Perform sector to block offset translations, to get various 1028 * sector and file offsets into the image. See VHDXSectorInfo 1029 */ 1030 static void vhdx_block_translate(BDRVVHDXState *s, int64_t sector_num, 1031 int nb_sectors, VHDXSectorInfo *sinfo) 1032 { 1033 uint32_t block_offset; 1034 1035 sinfo->bat_idx = sector_num >> s->sectors_per_block_bits; 1036 /* effectively a modulo - this gives us the offset into the block 1037 * (in sector sizes) for our sector number */ 1038 block_offset = sector_num - (sinfo->bat_idx << s->sectors_per_block_bits); 1039 /* the chunk ratio gives us the interleaving of the sector 1040 * bitmaps, so we need to advance our page block index by the 1041 * sector bitmaps entry number */ 1042 sinfo->bat_idx += sinfo->bat_idx >> s->chunk_ratio_bits; 1043 1044 /* the number of sectors we can read/write in this cycle */ 1045 sinfo->sectors_avail = s->sectors_per_block - block_offset; 1046 1047 sinfo->bytes_left = sinfo->sectors_avail << s->logical_sector_size_bits; 1048 1049 if (sinfo->sectors_avail > nb_sectors) { 1050 sinfo->sectors_avail = nb_sectors; 1051 } 1052 1053 sinfo->bytes_avail = sinfo->sectors_avail << s->logical_sector_size_bits; 1054 1055 sinfo->file_offset = s->bat[sinfo->bat_idx] & VHDX_BAT_FILE_OFF_MASK; 1056 1057 sinfo->block_offset = block_offset << s->logical_sector_size_bits; 1058 1059 /* The file offset must be past the header section, so must be > 0 */ 1060 if (sinfo->file_offset == 0) { 1061 return; 1062 } 1063 1064 /* block offset is the offset in vhdx logical sectors, in 1065 * the payload data block. Convert that to a byte offset 1066 * in the block, and add in the payload data block offset 1067 * in the file, in bytes, to get the final read address */ 1068 1069 sinfo->file_offset += sinfo->block_offset; 1070 } 1071 1072 1073 static int vhdx_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) 1074 { 1075 BDRVVHDXState *s = bs->opaque; 1076 1077 bdi->cluster_size = s->block_size; 1078 1079 bdi->unallocated_blocks_are_zero = 1080 (s->params.data_bits & VHDX_PARAMS_HAS_PARENT) == 0; 1081 1082 return 0; 1083 } 1084 1085 1086 static coroutine_fn int vhdx_co_readv(BlockDriverState *bs, int64_t sector_num, 1087 int nb_sectors, QEMUIOVector *qiov) 1088 { 1089 BDRVVHDXState *s = bs->opaque; 1090 int ret = 0; 1091 VHDXSectorInfo sinfo; 1092 uint64_t bytes_done = 0; 1093 QEMUIOVector hd_qiov; 1094 1095 qemu_iovec_init(&hd_qiov, qiov->niov); 1096 1097 qemu_co_mutex_lock(&s->lock); 1098 1099 while (nb_sectors > 0) { 1100 /* We are a differencing file, so we need to inspect the sector bitmap 1101 * to see if we have the data or not */ 1102 if (s->params.data_bits & VHDX_PARAMS_HAS_PARENT) { 1103 /* not supported yet */ 1104 ret = -ENOTSUP; 1105 goto exit; 1106 } else { 1107 vhdx_block_translate(s, sector_num, nb_sectors, &sinfo); 1108 1109 qemu_iovec_reset(&hd_qiov); 1110 qemu_iovec_concat(&hd_qiov, qiov, bytes_done, sinfo.bytes_avail); 1111 1112 /* check the payload block state */ 1113 switch (s->bat[sinfo.bat_idx] & VHDX_BAT_STATE_BIT_MASK) { 1114 case PAYLOAD_BLOCK_NOT_PRESENT: /* fall through */ 1115 case PAYLOAD_BLOCK_UNDEFINED: 1116 case PAYLOAD_BLOCK_UNMAPPED: 1117 case PAYLOAD_BLOCK_UNMAPPED_v095: 1118 case PAYLOAD_BLOCK_ZERO: 1119 /* return zero */ 1120 qemu_iovec_memset(&hd_qiov, 0, 0, sinfo.bytes_avail); 1121 break; 1122 case PAYLOAD_BLOCK_FULLY_PRESENT: 1123 qemu_co_mutex_unlock(&s->lock); 1124 ret = bdrv_co_readv(bs->file->bs, 1125 sinfo.file_offset >> BDRV_SECTOR_BITS, 1126 sinfo.sectors_avail, &hd_qiov); 1127 qemu_co_mutex_lock(&s->lock); 1128 if (ret < 0) { 1129 goto exit; 1130 } 1131 break; 1132 case PAYLOAD_BLOCK_PARTIALLY_PRESENT: 1133 /* we don't yet support difference files, fall through 1134 * to error */ 1135 default: 1136 ret = -EIO; 1137 goto exit; 1138 break; 1139 } 1140 nb_sectors -= sinfo.sectors_avail; 1141 sector_num += sinfo.sectors_avail; 1142 bytes_done += sinfo.bytes_avail; 1143 } 1144 } 1145 ret = 0; 1146 exit: 1147 qemu_co_mutex_unlock(&s->lock); 1148 qemu_iovec_destroy(&hd_qiov); 1149 return ret; 1150 } 1151 1152 /* 1153 * Allocate a new payload block at the end of the file. 1154 * 1155 * Allocation will happen at 1MB alignment inside the file 1156 * 1157 * Returns the file offset start of the new payload block 1158 */ 1159 static int vhdx_allocate_block(BlockDriverState *bs, BDRVVHDXState *s, 1160 uint64_t *new_offset) 1161 { 1162 *new_offset = bdrv_getlength(bs->file->bs); 1163 1164 /* per the spec, the address for a block is in units of 1MB */ 1165 *new_offset = ROUND_UP(*new_offset, 1024 * 1024); 1166 1167 return bdrv_truncate(bs->file->bs, *new_offset + s->block_size); 1168 } 1169 1170 /* 1171 * Update the BAT table entry with the new file offset, and the new entry 1172 * state */ 1173 static void vhdx_update_bat_table_entry(BlockDriverState *bs, BDRVVHDXState *s, 1174 VHDXSectorInfo *sinfo, 1175 uint64_t *bat_entry_le, 1176 uint64_t *bat_offset, int state) 1177 { 1178 /* The BAT entry is a uint64, with 44 bits for the file offset in units of 1179 * 1MB, and 3 bits for the block state. */ 1180 if ((state == PAYLOAD_BLOCK_ZERO) || 1181 (state == PAYLOAD_BLOCK_UNDEFINED) || 1182 (state == PAYLOAD_BLOCK_NOT_PRESENT) || 1183 (state == PAYLOAD_BLOCK_UNMAPPED)) { 1184 s->bat[sinfo->bat_idx] = 0; /* For PAYLOAD_BLOCK_ZERO, the 1185 FileOffsetMB field is denoted as 1186 'reserved' in the v1.0 spec. If it is 1187 non-zero, MS Hyper-V will fail to read 1188 the disk image */ 1189 } else { 1190 s->bat[sinfo->bat_idx] = sinfo->file_offset; 1191 } 1192 1193 s->bat[sinfo->bat_idx] |= state & VHDX_BAT_STATE_BIT_MASK; 1194 1195 *bat_entry_le = cpu_to_le64(s->bat[sinfo->bat_idx]); 1196 *bat_offset = s->bat_offset + sinfo->bat_idx * sizeof(VHDXBatEntry); 1197 1198 } 1199 1200 /* Per the spec, on the first write of guest-visible data to the file the 1201 * data write guid must be updated in the header */ 1202 int vhdx_user_visible_write(BlockDriverState *bs, BDRVVHDXState *s) 1203 { 1204 int ret = 0; 1205 if (s->first_visible_write) { 1206 s->first_visible_write = false; 1207 ret = vhdx_update_headers(bs, s, true, NULL); 1208 } 1209 return ret; 1210 } 1211 1212 static coroutine_fn int vhdx_co_writev(BlockDriverState *bs, int64_t sector_num, 1213 int nb_sectors, QEMUIOVector *qiov) 1214 { 1215 int ret = -ENOTSUP; 1216 BDRVVHDXState *s = bs->opaque; 1217 VHDXSectorInfo sinfo; 1218 uint64_t bytes_done = 0; 1219 uint64_t bat_entry = 0; 1220 uint64_t bat_entry_offset = 0; 1221 QEMUIOVector hd_qiov; 1222 struct iovec iov1 = { 0 }; 1223 struct iovec iov2 = { 0 }; 1224 int sectors_to_write; 1225 int bat_state; 1226 uint64_t bat_prior_offset = 0; 1227 bool bat_update = false; 1228 1229 qemu_iovec_init(&hd_qiov, qiov->niov); 1230 1231 qemu_co_mutex_lock(&s->lock); 1232 1233 ret = vhdx_user_visible_write(bs, s); 1234 if (ret < 0) { 1235 goto exit; 1236 } 1237 1238 while (nb_sectors > 0) { 1239 bool use_zero_buffers = false; 1240 bat_update = false; 1241 if (s->params.data_bits & VHDX_PARAMS_HAS_PARENT) { 1242 /* not supported yet */ 1243 ret = -ENOTSUP; 1244 goto exit; 1245 } else { 1246 vhdx_block_translate(s, sector_num, nb_sectors, &sinfo); 1247 sectors_to_write = sinfo.sectors_avail; 1248 1249 qemu_iovec_reset(&hd_qiov); 1250 /* check the payload block state */ 1251 bat_state = s->bat[sinfo.bat_idx] & VHDX_BAT_STATE_BIT_MASK; 1252 switch (bat_state) { 1253 case PAYLOAD_BLOCK_ZERO: 1254 /* in this case, we need to preserve zero writes for 1255 * data that is not part of this write, so we must pad 1256 * the rest of the buffer to zeroes */ 1257 1258 /* if we are on a posix system with ftruncate() that extends 1259 * a file, then it is zero-filled for us. On Win32, the raw 1260 * layer uses SetFilePointer and SetFileEnd, which does not 1261 * zero fill AFAIK */ 1262 1263 /* Queue another write of zero buffers if the underlying file 1264 * does not zero-fill on file extension */ 1265 1266 if (bdrv_has_zero_init(bs->file->bs) == 0) { 1267 use_zero_buffers = true; 1268 1269 /* zero fill the front, if any */ 1270 if (sinfo.block_offset) { 1271 iov1.iov_len = sinfo.block_offset; 1272 iov1.iov_base = qemu_blockalign(bs, iov1.iov_len); 1273 memset(iov1.iov_base, 0, iov1.iov_len); 1274 qemu_iovec_concat_iov(&hd_qiov, &iov1, 1, 0, 1275 iov1.iov_len); 1276 sectors_to_write += iov1.iov_len >> BDRV_SECTOR_BITS; 1277 } 1278 1279 /* our actual data */ 1280 qemu_iovec_concat(&hd_qiov, qiov, bytes_done, 1281 sinfo.bytes_avail); 1282 1283 /* zero fill the back, if any */ 1284 if ((sinfo.bytes_avail - sinfo.block_offset) < 1285 s->block_size) { 1286 iov2.iov_len = s->block_size - 1287 (sinfo.bytes_avail + sinfo.block_offset); 1288 iov2.iov_base = qemu_blockalign(bs, iov2.iov_len); 1289 memset(iov2.iov_base, 0, iov2.iov_len); 1290 qemu_iovec_concat_iov(&hd_qiov, &iov2, 1, 0, 1291 iov2.iov_len); 1292 sectors_to_write += iov2.iov_len >> BDRV_SECTOR_BITS; 1293 } 1294 } 1295 /* fall through */ 1296 case PAYLOAD_BLOCK_NOT_PRESENT: /* fall through */ 1297 case PAYLOAD_BLOCK_UNMAPPED: 1298 case PAYLOAD_BLOCK_UNMAPPED_v095: 1299 case PAYLOAD_BLOCK_UNDEFINED: 1300 bat_prior_offset = sinfo.file_offset; 1301 ret = vhdx_allocate_block(bs, s, &sinfo.file_offset); 1302 if (ret < 0) { 1303 goto exit; 1304 } 1305 /* once we support differencing files, this may also be 1306 * partially present */ 1307 /* update block state to the newly specified state */ 1308 vhdx_update_bat_table_entry(bs, s, &sinfo, &bat_entry, 1309 &bat_entry_offset, 1310 PAYLOAD_BLOCK_FULLY_PRESENT); 1311 bat_update = true; 1312 /* since we just allocated a block, file_offset is the 1313 * beginning of the payload block. It needs to be the 1314 * write address, which includes the offset into the block */ 1315 if (!use_zero_buffers) { 1316 sinfo.file_offset += sinfo.block_offset; 1317 } 1318 /* fall through */ 1319 case PAYLOAD_BLOCK_FULLY_PRESENT: 1320 /* if the file offset address is in the header zone, 1321 * there is a problem */ 1322 if (sinfo.file_offset < (1024 * 1024)) { 1323 ret = -EFAULT; 1324 goto error_bat_restore; 1325 } 1326 1327 if (!use_zero_buffers) { 1328 qemu_iovec_concat(&hd_qiov, qiov, bytes_done, 1329 sinfo.bytes_avail); 1330 } 1331 /* block exists, so we can just overwrite it */ 1332 qemu_co_mutex_unlock(&s->lock); 1333 ret = bdrv_co_writev(bs->file->bs, 1334 sinfo.file_offset >> BDRV_SECTOR_BITS, 1335 sectors_to_write, &hd_qiov); 1336 qemu_co_mutex_lock(&s->lock); 1337 if (ret < 0) { 1338 goto error_bat_restore; 1339 } 1340 break; 1341 case PAYLOAD_BLOCK_PARTIALLY_PRESENT: 1342 /* we don't yet support difference files, fall through 1343 * to error */ 1344 default: 1345 ret = -EIO; 1346 goto exit; 1347 break; 1348 } 1349 1350 if (bat_update) { 1351 /* this will update the BAT entry into the log journal, and 1352 * then flush the log journal out to disk */ 1353 ret = vhdx_log_write_and_flush(bs, s, &bat_entry, 1354 sizeof(VHDXBatEntry), 1355 bat_entry_offset); 1356 if (ret < 0) { 1357 goto exit; 1358 } 1359 } 1360 1361 nb_sectors -= sinfo.sectors_avail; 1362 sector_num += sinfo.sectors_avail; 1363 bytes_done += sinfo.bytes_avail; 1364 1365 } 1366 } 1367 1368 goto exit; 1369 1370 error_bat_restore: 1371 if (bat_update) { 1372 /* keep metadata in sync, and restore the bat entry state 1373 * if error. */ 1374 sinfo.file_offset = bat_prior_offset; 1375 vhdx_update_bat_table_entry(bs, s, &sinfo, &bat_entry, 1376 &bat_entry_offset, bat_state); 1377 } 1378 exit: 1379 qemu_vfree(iov1.iov_base); 1380 qemu_vfree(iov2.iov_base); 1381 qemu_co_mutex_unlock(&s->lock); 1382 qemu_iovec_destroy(&hd_qiov); 1383 return ret; 1384 } 1385 1386 1387 1388 /* 1389 * Create VHDX Headers 1390 * 1391 * There are 2 headers, and the highest sequence number will represent 1392 * the active header 1393 */ 1394 static int vhdx_create_new_headers(BlockDriverState *bs, uint64_t image_size, 1395 uint32_t log_size) 1396 { 1397 int ret = 0; 1398 VHDXHeader *hdr = NULL; 1399 1400 hdr = g_new0(VHDXHeader, 1); 1401 1402 hdr->signature = VHDX_HEADER_SIGNATURE; 1403 hdr->sequence_number = g_random_int(); 1404 hdr->log_version = 0; 1405 hdr->version = 1; 1406 hdr->log_length = log_size; 1407 hdr->log_offset = VHDX_HEADER_SECTION_END; 1408 vhdx_guid_generate(&hdr->file_write_guid); 1409 vhdx_guid_generate(&hdr->data_write_guid); 1410 1411 ret = vhdx_write_header(bs, hdr, VHDX_HEADER1_OFFSET, false); 1412 if (ret < 0) { 1413 goto exit; 1414 } 1415 hdr->sequence_number++; 1416 ret = vhdx_write_header(bs, hdr, VHDX_HEADER2_OFFSET, false); 1417 if (ret < 0) { 1418 goto exit; 1419 } 1420 1421 exit: 1422 g_free(hdr); 1423 return ret; 1424 } 1425 1426 #define VHDX_METADATA_ENTRY_BUFFER_SIZE \ 1427 (sizeof(VHDXFileParameters) +\ 1428 sizeof(VHDXVirtualDiskSize) +\ 1429 sizeof(VHDXPage83Data) +\ 1430 sizeof(VHDXVirtualDiskLogicalSectorSize) +\ 1431 sizeof(VHDXVirtualDiskPhysicalSectorSize)) 1432 1433 /* 1434 * Create the Metadata entries. 1435 * 1436 * For more details on the entries, see section 3.5 (pg 29) in the 1437 * VHDX 1.00 specification. 1438 * 1439 * We support 5 metadata entries (all required by spec): 1440 * File Parameters, 1441 * Virtual Disk Size, 1442 * Page 83 Data, 1443 * Logical Sector Size, 1444 * Physical Sector Size 1445 * 1446 * The first 64KB of the Metadata section is reserved for the metadata 1447 * header and entries; beyond that, the metadata items themselves reside. 1448 */ 1449 static int vhdx_create_new_metadata(BlockDriverState *bs, 1450 uint64_t image_size, 1451 uint32_t block_size, 1452 uint32_t sector_size, 1453 uint64_t metadata_offset, 1454 VHDXImageType type) 1455 { 1456 int ret = 0; 1457 uint32_t offset = 0; 1458 void *buffer = NULL; 1459 void *entry_buffer; 1460 VHDXMetadataTableHeader *md_table; 1461 VHDXMetadataTableEntry *md_table_entry; 1462 1463 /* Metadata entries */ 1464 VHDXFileParameters *mt_file_params; 1465 VHDXVirtualDiskSize *mt_virtual_size; 1466 VHDXPage83Data *mt_page83; 1467 VHDXVirtualDiskLogicalSectorSize *mt_log_sector_size; 1468 VHDXVirtualDiskPhysicalSectorSize *mt_phys_sector_size; 1469 1470 entry_buffer = g_malloc0(VHDX_METADATA_ENTRY_BUFFER_SIZE); 1471 1472 mt_file_params = entry_buffer; 1473 offset += sizeof(VHDXFileParameters); 1474 mt_virtual_size = entry_buffer + offset; 1475 offset += sizeof(VHDXVirtualDiskSize); 1476 mt_page83 = entry_buffer + offset; 1477 offset += sizeof(VHDXPage83Data); 1478 mt_log_sector_size = entry_buffer + offset; 1479 offset += sizeof(VHDXVirtualDiskLogicalSectorSize); 1480 mt_phys_sector_size = entry_buffer + offset; 1481 1482 mt_file_params->block_size = cpu_to_le32(block_size); 1483 if (type == VHDX_TYPE_FIXED) { 1484 mt_file_params->data_bits |= VHDX_PARAMS_LEAVE_BLOCKS_ALLOCED; 1485 cpu_to_le32s(&mt_file_params->data_bits); 1486 } 1487 1488 vhdx_guid_generate(&mt_page83->page_83_data); 1489 cpu_to_leguids(&mt_page83->page_83_data); 1490 mt_virtual_size->virtual_disk_size = cpu_to_le64(image_size); 1491 mt_log_sector_size->logical_sector_size = cpu_to_le32(sector_size); 1492 mt_phys_sector_size->physical_sector_size = cpu_to_le32(sector_size); 1493 1494 buffer = g_malloc0(VHDX_HEADER_BLOCK_SIZE); 1495 md_table = buffer; 1496 1497 md_table->signature = VHDX_METADATA_SIGNATURE; 1498 md_table->entry_count = 5; 1499 vhdx_metadata_header_le_export(md_table); 1500 1501 1502 /* This will reference beyond the reserved table portion */ 1503 offset = 64 * KiB; 1504 1505 md_table_entry = buffer + sizeof(VHDXMetadataTableHeader); 1506 1507 md_table_entry[0].item_id = file_param_guid; 1508 md_table_entry[0].offset = offset; 1509 md_table_entry[0].length = sizeof(VHDXFileParameters); 1510 md_table_entry[0].data_bits |= VHDX_META_FLAGS_IS_REQUIRED; 1511 offset += md_table_entry[0].length; 1512 vhdx_metadata_entry_le_export(&md_table_entry[0]); 1513 1514 md_table_entry[1].item_id = virtual_size_guid; 1515 md_table_entry[1].offset = offset; 1516 md_table_entry[1].length = sizeof(VHDXVirtualDiskSize); 1517 md_table_entry[1].data_bits |= VHDX_META_FLAGS_IS_REQUIRED | 1518 VHDX_META_FLAGS_IS_VIRTUAL_DISK; 1519 offset += md_table_entry[1].length; 1520 vhdx_metadata_entry_le_export(&md_table_entry[1]); 1521 1522 md_table_entry[2].item_id = page83_guid; 1523 md_table_entry[2].offset = offset; 1524 md_table_entry[2].length = sizeof(VHDXPage83Data); 1525 md_table_entry[2].data_bits |= VHDX_META_FLAGS_IS_REQUIRED | 1526 VHDX_META_FLAGS_IS_VIRTUAL_DISK; 1527 offset += md_table_entry[2].length; 1528 vhdx_metadata_entry_le_export(&md_table_entry[2]); 1529 1530 md_table_entry[3].item_id = logical_sector_guid; 1531 md_table_entry[3].offset = offset; 1532 md_table_entry[3].length = sizeof(VHDXVirtualDiskLogicalSectorSize); 1533 md_table_entry[3].data_bits |= VHDX_META_FLAGS_IS_REQUIRED | 1534 VHDX_META_FLAGS_IS_VIRTUAL_DISK; 1535 offset += md_table_entry[3].length; 1536 vhdx_metadata_entry_le_export(&md_table_entry[3]); 1537 1538 md_table_entry[4].item_id = phys_sector_guid; 1539 md_table_entry[4].offset = offset; 1540 md_table_entry[4].length = sizeof(VHDXVirtualDiskPhysicalSectorSize); 1541 md_table_entry[4].data_bits |= VHDX_META_FLAGS_IS_REQUIRED | 1542 VHDX_META_FLAGS_IS_VIRTUAL_DISK; 1543 vhdx_metadata_entry_le_export(&md_table_entry[4]); 1544 1545 ret = bdrv_pwrite(bs, metadata_offset, buffer, VHDX_HEADER_BLOCK_SIZE); 1546 if (ret < 0) { 1547 goto exit; 1548 } 1549 1550 ret = bdrv_pwrite(bs, metadata_offset + (64 * KiB), entry_buffer, 1551 VHDX_METADATA_ENTRY_BUFFER_SIZE); 1552 if (ret < 0) { 1553 goto exit; 1554 } 1555 1556 1557 exit: 1558 g_free(buffer); 1559 g_free(entry_buffer); 1560 return ret; 1561 } 1562 1563 /* This create the actual BAT itself. We currently only support 1564 * 'Dynamic' and 'Fixed' image types. 1565 * 1566 * Dynamic images: default state of the BAT is all zeroes. 1567 * 1568 * Fixed images: default state of the BAT is fully populated, with 1569 * file offsets and state PAYLOAD_BLOCK_FULLY_PRESENT. 1570 */ 1571 static int vhdx_create_bat(BlockDriverState *bs, BDRVVHDXState *s, 1572 uint64_t image_size, VHDXImageType type, 1573 bool use_zero_blocks, uint64_t file_offset, 1574 uint32_t length) 1575 { 1576 int ret = 0; 1577 uint64_t data_file_offset; 1578 uint64_t total_sectors = 0; 1579 uint64_t sector_num = 0; 1580 uint64_t unused; 1581 int block_state; 1582 VHDXSectorInfo sinfo; 1583 1584 assert(s->bat == NULL); 1585 1586 /* this gives a data start after BAT/bitmap entries, and well 1587 * past any metadata entries (with a 4 MB buffer for future 1588 * expansion */ 1589 data_file_offset = file_offset + length + 5 * MiB; 1590 total_sectors = image_size >> s->logical_sector_size_bits; 1591 1592 if (type == VHDX_TYPE_DYNAMIC) { 1593 /* All zeroes, so we can just extend the file - the end of the BAT 1594 * is the furthest thing we have written yet */ 1595 ret = bdrv_truncate(bs, data_file_offset); 1596 if (ret < 0) { 1597 goto exit; 1598 } 1599 } else if (type == VHDX_TYPE_FIXED) { 1600 ret = bdrv_truncate(bs, data_file_offset + image_size); 1601 if (ret < 0) { 1602 goto exit; 1603 } 1604 } else { 1605 ret = -ENOTSUP; 1606 goto exit; 1607 } 1608 1609 if (type == VHDX_TYPE_FIXED || 1610 use_zero_blocks || 1611 bdrv_has_zero_init(bs) == 0) { 1612 /* for a fixed file, the default BAT entry is not zero */ 1613 s->bat = g_try_malloc0(length); 1614 if (length && s->bat == NULL) { 1615 ret = -ENOMEM; 1616 goto exit; 1617 } 1618 block_state = type == VHDX_TYPE_FIXED ? PAYLOAD_BLOCK_FULLY_PRESENT : 1619 PAYLOAD_BLOCK_NOT_PRESENT; 1620 block_state = use_zero_blocks ? PAYLOAD_BLOCK_ZERO : block_state; 1621 /* fill the BAT by emulating sector writes of sectors_per_block size */ 1622 while (sector_num < total_sectors) { 1623 vhdx_block_translate(s, sector_num, s->sectors_per_block, &sinfo); 1624 sinfo.file_offset = data_file_offset + 1625 (sector_num << s->logical_sector_size_bits); 1626 sinfo.file_offset = ROUND_UP(sinfo.file_offset, MiB); 1627 vhdx_update_bat_table_entry(bs, s, &sinfo, &unused, &unused, 1628 block_state); 1629 cpu_to_le64s(&s->bat[sinfo.bat_idx]); 1630 sector_num += s->sectors_per_block; 1631 } 1632 ret = bdrv_pwrite(bs, file_offset, s->bat, length); 1633 if (ret < 0) { 1634 goto exit; 1635 } 1636 } 1637 1638 1639 1640 exit: 1641 g_free(s->bat); 1642 return ret; 1643 } 1644 1645 /* Creates the region table header, and region table entries. 1646 * There are 2 supported region table entries: BAT, and Metadata/ 1647 * 1648 * As the calculations for the BAT region table are also needed 1649 * to create the BAT itself, we will also cause the BAT to be 1650 * created. 1651 */ 1652 static int vhdx_create_new_region_table(BlockDriverState *bs, 1653 uint64_t image_size, 1654 uint32_t block_size, 1655 uint32_t sector_size, 1656 uint32_t log_size, 1657 bool use_zero_blocks, 1658 VHDXImageType type, 1659 uint64_t *metadata_offset) 1660 { 1661 int ret = 0; 1662 uint32_t offset = 0; 1663 void *buffer = NULL; 1664 uint64_t bat_file_offset; 1665 uint32_t bat_length; 1666 BDRVVHDXState *s = NULL; 1667 VHDXRegionTableHeader *region_table; 1668 VHDXRegionTableEntry *rt_bat; 1669 VHDXRegionTableEntry *rt_metadata; 1670 1671 assert(metadata_offset != NULL); 1672 1673 /* Populate enough of the BDRVVHDXState to be able to use the 1674 * pre-existing BAT calculation, translation, and update functions */ 1675 s = g_new0(BDRVVHDXState, 1); 1676 1677 s->chunk_ratio = (VHDX_MAX_SECTORS_PER_BLOCK) * 1678 (uint64_t) sector_size / (uint64_t) block_size; 1679 1680 s->sectors_per_block = block_size / sector_size; 1681 s->virtual_disk_size = image_size; 1682 s->block_size = block_size; 1683 s->logical_sector_size = sector_size; 1684 1685 vhdx_set_shift_bits(s); 1686 1687 vhdx_calc_bat_entries(s); 1688 1689 /* At this point the VHDX state is populated enough for creation */ 1690 1691 /* a single buffer is used so we can calculate the checksum over the 1692 * entire 64KB block */ 1693 buffer = g_malloc0(VHDX_HEADER_BLOCK_SIZE); 1694 region_table = buffer; 1695 offset += sizeof(VHDXRegionTableHeader); 1696 rt_bat = buffer + offset; 1697 offset += sizeof(VHDXRegionTableEntry); 1698 rt_metadata = buffer + offset; 1699 1700 region_table->signature = VHDX_REGION_SIGNATURE; 1701 region_table->entry_count = 2; /* BAT and Metadata */ 1702 1703 rt_bat->guid = bat_guid; 1704 rt_bat->length = ROUND_UP(s->bat_entries * sizeof(VHDXBatEntry), MiB); 1705 rt_bat->file_offset = ROUND_UP(VHDX_HEADER_SECTION_END + log_size, MiB); 1706 s->bat_offset = rt_bat->file_offset; 1707 1708 rt_metadata->guid = metadata_guid; 1709 rt_metadata->file_offset = ROUND_UP(rt_bat->file_offset + rt_bat->length, 1710 MiB); 1711 rt_metadata->length = 1 * MiB; /* min size, and more than enough */ 1712 *metadata_offset = rt_metadata->file_offset; 1713 1714 bat_file_offset = rt_bat->file_offset; 1715 bat_length = rt_bat->length; 1716 1717 vhdx_region_header_le_export(region_table); 1718 vhdx_region_entry_le_export(rt_bat); 1719 vhdx_region_entry_le_export(rt_metadata); 1720 1721 vhdx_update_checksum(buffer, VHDX_HEADER_BLOCK_SIZE, 1722 offsetof(VHDXRegionTableHeader, checksum)); 1723 1724 1725 /* The region table gives us the data we need to create the BAT, 1726 * so do that now */ 1727 ret = vhdx_create_bat(bs, s, image_size, type, use_zero_blocks, 1728 bat_file_offset, bat_length); 1729 if (ret < 0) { 1730 goto exit; 1731 } 1732 1733 /* Now write out the region headers to disk */ 1734 ret = bdrv_pwrite(bs, VHDX_REGION_TABLE_OFFSET, buffer, 1735 VHDX_HEADER_BLOCK_SIZE); 1736 if (ret < 0) { 1737 goto exit; 1738 } 1739 1740 ret = bdrv_pwrite(bs, VHDX_REGION_TABLE2_OFFSET, buffer, 1741 VHDX_HEADER_BLOCK_SIZE); 1742 if (ret < 0) { 1743 goto exit; 1744 } 1745 1746 exit: 1747 g_free(s); 1748 g_free(buffer); 1749 return ret; 1750 } 1751 1752 /* We need to create the following elements: 1753 * 1754 * .-----------------------------------------------------------------. 1755 * | (A) | (B) | (C) | (D) | (E) | 1756 * | File ID | Header1 | Header 2 | Region Tbl 1 | Region Tbl 2 | 1757 * | | | | | | 1758 * .-----------------------------------------------------------------. 1759 * 0 64KB 128KB 192KB 256KB 320KB 1760 * 1761 * 1762 * .---- ~ ----------- ~ ------------ ~ ---------------- ~ -----------. 1763 * | (F) | (G) | (H) | | 1764 * | Journal Log | BAT / Bitmap | Metadata | .... data ...... | 1765 * | | | | | 1766 * .---- ~ ----------- ~ ------------ ~ ---------------- ~ -----------. 1767 * 1MB 1768 */ 1769 static int vhdx_create(const char *filename, QemuOpts *opts, Error **errp) 1770 { 1771 int ret = 0; 1772 uint64_t image_size = (uint64_t) 2 * GiB; 1773 uint32_t log_size = 1 * MiB; 1774 uint32_t block_size = 0; 1775 uint64_t signature; 1776 uint64_t metadata_offset; 1777 bool use_zero_blocks = false; 1778 1779 gunichar2 *creator = NULL; 1780 glong creator_items; 1781 BlockDriverState *bs; 1782 char *type = NULL; 1783 VHDXImageType image_type; 1784 Error *local_err = NULL; 1785 1786 image_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0), 1787 BDRV_SECTOR_SIZE); 1788 log_size = qemu_opt_get_size_del(opts, VHDX_BLOCK_OPT_LOG_SIZE, 0); 1789 block_size = qemu_opt_get_size_del(opts, VHDX_BLOCK_OPT_BLOCK_SIZE, 0); 1790 type = qemu_opt_get_del(opts, BLOCK_OPT_SUBFMT); 1791 use_zero_blocks = qemu_opt_get_bool_del(opts, VHDX_BLOCK_OPT_ZERO, true); 1792 1793 if (image_size > VHDX_MAX_IMAGE_SIZE) { 1794 error_setg_errno(errp, EINVAL, "Image size too large; max of 64TB"); 1795 ret = -EINVAL; 1796 goto exit; 1797 } 1798 1799 if (type == NULL) { 1800 type = g_strdup("dynamic"); 1801 } 1802 1803 if (!strcmp(type, "dynamic")) { 1804 image_type = VHDX_TYPE_DYNAMIC; 1805 } else if (!strcmp(type, "fixed")) { 1806 image_type = VHDX_TYPE_FIXED; 1807 } else if (!strcmp(type, "differencing")) { 1808 error_setg_errno(errp, ENOTSUP, 1809 "Differencing files not yet supported"); 1810 ret = -ENOTSUP; 1811 goto exit; 1812 } else { 1813 ret = -EINVAL; 1814 goto exit; 1815 } 1816 1817 /* These are pretty arbitrary, and mainly designed to keep the BAT 1818 * size reasonable to load into RAM */ 1819 if (block_size == 0) { 1820 if (image_size > 32 * TiB) { 1821 block_size = 64 * MiB; 1822 } else if (image_size > (uint64_t) 100 * GiB) { 1823 block_size = 32 * MiB; 1824 } else if (image_size > 1 * GiB) { 1825 block_size = 16 * MiB; 1826 } else { 1827 block_size = 8 * MiB; 1828 } 1829 } 1830 1831 1832 /* make the log size close to what was specified, but must be 1833 * min 1MB, and multiple of 1MB */ 1834 log_size = ROUND_UP(log_size, MiB); 1835 1836 block_size = ROUND_UP(block_size, MiB); 1837 block_size = block_size > VHDX_BLOCK_SIZE_MAX ? VHDX_BLOCK_SIZE_MAX : 1838 block_size; 1839 1840 ret = bdrv_create_file(filename, opts, &local_err); 1841 if (ret < 0) { 1842 error_propagate(errp, local_err); 1843 goto exit; 1844 } 1845 1846 bs = NULL; 1847 ret = bdrv_open(&bs, filename, NULL, NULL, BDRV_O_RDWR | BDRV_O_PROTOCOL, 1848 &local_err); 1849 if (ret < 0) { 1850 error_propagate(errp, local_err); 1851 goto exit; 1852 } 1853 1854 /* Create (A) */ 1855 1856 /* The creator field is optional, but may be useful for 1857 * debugging / diagnostics */ 1858 creator = g_utf8_to_utf16("QEMU v" QEMU_VERSION, -1, NULL, 1859 &creator_items, NULL); 1860 signature = cpu_to_le64(VHDX_FILE_SIGNATURE); 1861 ret = bdrv_pwrite(bs, VHDX_FILE_ID_OFFSET, &signature, sizeof(signature)); 1862 if (ret < 0) { 1863 goto delete_and_exit; 1864 } 1865 if (creator) { 1866 ret = bdrv_pwrite(bs, VHDX_FILE_ID_OFFSET + sizeof(signature), 1867 creator, creator_items * sizeof(gunichar2)); 1868 if (ret < 0) { 1869 goto delete_and_exit; 1870 } 1871 } 1872 1873 1874 /* Creates (B),(C) */ 1875 ret = vhdx_create_new_headers(bs, image_size, log_size); 1876 if (ret < 0) { 1877 goto delete_and_exit; 1878 } 1879 1880 /* Creates (D),(E),(G) explicitly. (F) created as by-product */ 1881 ret = vhdx_create_new_region_table(bs, image_size, block_size, 512, 1882 log_size, use_zero_blocks, image_type, 1883 &metadata_offset); 1884 if (ret < 0) { 1885 goto delete_and_exit; 1886 } 1887 1888 /* Creates (H) */ 1889 ret = vhdx_create_new_metadata(bs, image_size, block_size, 512, 1890 metadata_offset, image_type); 1891 if (ret < 0) { 1892 goto delete_and_exit; 1893 } 1894 1895 1896 delete_and_exit: 1897 bdrv_unref(bs); 1898 exit: 1899 g_free(type); 1900 g_free(creator); 1901 return ret; 1902 } 1903 1904 /* If opened r/w, the VHDX driver will automatically replay the log, 1905 * if one is present, inside the vhdx_open() call. 1906 * 1907 * If qemu-img check -r all is called, the image is automatically opened 1908 * r/w and any log has already been replayed, so there is nothing (currently) 1909 * for us to do here 1910 */ 1911 static int vhdx_check(BlockDriverState *bs, BdrvCheckResult *result, 1912 BdrvCheckMode fix) 1913 { 1914 BDRVVHDXState *s = bs->opaque; 1915 1916 if (s->log_replayed_on_open) { 1917 result->corruptions_fixed++; 1918 } 1919 return 0; 1920 } 1921 1922 static QemuOptsList vhdx_create_opts = { 1923 .name = "vhdx-create-opts", 1924 .head = QTAILQ_HEAD_INITIALIZER(vhdx_create_opts.head), 1925 .desc = { 1926 { 1927 .name = BLOCK_OPT_SIZE, 1928 .type = QEMU_OPT_SIZE, 1929 .help = "Virtual disk size; max of 64TB." 1930 }, 1931 { 1932 .name = VHDX_BLOCK_OPT_LOG_SIZE, 1933 .type = QEMU_OPT_SIZE, 1934 .def_value_str = stringify(DEFAULT_LOG_SIZE), 1935 .help = "Log size; min 1MB." 1936 }, 1937 { 1938 .name = VHDX_BLOCK_OPT_BLOCK_SIZE, 1939 .type = QEMU_OPT_SIZE, 1940 .def_value_str = stringify(0), 1941 .help = "Block Size; min 1MB, max 256MB. " \ 1942 "0 means auto-calculate based on image size." 1943 }, 1944 { 1945 .name = BLOCK_OPT_SUBFMT, 1946 .type = QEMU_OPT_STRING, 1947 .help = "VHDX format type, can be either 'dynamic' or 'fixed'. "\ 1948 "Default is 'dynamic'." 1949 }, 1950 { 1951 .name = VHDX_BLOCK_OPT_ZERO, 1952 .type = QEMU_OPT_BOOL, 1953 .help = "Force use of payload blocks of type 'ZERO'. "\ 1954 "Non-standard, but default. Do not set to 'off' when "\ 1955 "using 'qemu-img convert' with subformat=dynamic." 1956 }, 1957 { NULL } 1958 } 1959 }; 1960 1961 static BlockDriver bdrv_vhdx = { 1962 .format_name = "vhdx", 1963 .instance_size = sizeof(BDRVVHDXState), 1964 .bdrv_probe = vhdx_probe, 1965 .bdrv_open = vhdx_open, 1966 .bdrv_close = vhdx_close, 1967 .bdrv_reopen_prepare = vhdx_reopen_prepare, 1968 .bdrv_co_readv = vhdx_co_readv, 1969 .bdrv_co_writev = vhdx_co_writev, 1970 .bdrv_create = vhdx_create, 1971 .bdrv_get_info = vhdx_get_info, 1972 .bdrv_check = vhdx_check, 1973 .bdrv_has_zero_init = bdrv_has_zero_init_1, 1974 1975 .create_opts = &vhdx_create_opts, 1976 }; 1977 1978 static void bdrv_vhdx_init(void) 1979 { 1980 bdrv_register(&bdrv_vhdx); 1981 } 1982 1983 block_init(bdrv_vhdx_init); 1984