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-common.h" 19 #include "block/block_int.h" 20 #include "qemu/module.h" 21 #include "qemu/crc32c.h" 22 #include "block/vhdx.h" 23 #include "migration/migration.h" 24 25 #include <uuid/uuid.h> 26 #include <glib.h> 27 28 /* Options for VHDX creation */ 29 30 #define VHDX_BLOCK_OPT_LOG_SIZE "log_size" 31 #define VHDX_BLOCK_OPT_BLOCK_SIZE "block_size" 32 #define VHDX_BLOCK_OPT_ZERO "block_state_zero" 33 34 typedef enum VHDXImageType { 35 VHDX_TYPE_DYNAMIC = 0, 36 VHDX_TYPE_FIXED, 37 VHDX_TYPE_DIFFERENCING, /* Currently unsupported */ 38 } VHDXImageType; 39 40 /* Several metadata and region table data entries are identified by 41 * guids in a MS-specific GUID format. */ 42 43 44 /* ------- Known Region Table GUIDs ---------------------- */ 45 static const MSGUID bat_guid = { .data1 = 0x2dc27766, 46 .data2 = 0xf623, 47 .data3 = 0x4200, 48 .data4 = { 0x9d, 0x64, 0x11, 0x5e, 49 0x9b, 0xfd, 0x4a, 0x08} }; 50 51 static const MSGUID metadata_guid = { .data1 = 0x8b7ca206, 52 .data2 = 0x4790, 53 .data3 = 0x4b9a, 54 .data4 = { 0xb8, 0xfe, 0x57, 0x5f, 55 0x05, 0x0f, 0x88, 0x6e} }; 56 57 58 59 /* ------- Known Metadata Entry GUIDs ---------------------- */ 60 static const MSGUID file_param_guid = { .data1 = 0xcaa16737, 61 .data2 = 0xfa36, 62 .data3 = 0x4d43, 63 .data4 = { 0xb3, 0xb6, 0x33, 0xf0, 64 0xaa, 0x44, 0xe7, 0x6b} }; 65 66 static const MSGUID virtual_size_guid = { .data1 = 0x2FA54224, 67 .data2 = 0xcd1b, 68 .data3 = 0x4876, 69 .data4 = { 0xb2, 0x11, 0x5d, 0xbe, 70 0xd8, 0x3b, 0xf4, 0xb8} }; 71 72 static const MSGUID page83_guid = { .data1 = 0xbeca12ab, 73 .data2 = 0xb2e6, 74 .data3 = 0x4523, 75 .data4 = { 0x93, 0xef, 0xc3, 0x09, 76 0xe0, 0x00, 0xc7, 0x46} }; 77 78 79 static const MSGUID phys_sector_guid = { .data1 = 0xcda348c7, 80 .data2 = 0x445d, 81 .data3 = 0x4471, 82 .data4 = { 0x9c, 0xc9, 0xe9, 0x88, 83 0x52, 0x51, 0xc5, 0x56} }; 84 85 static const MSGUID parent_locator_guid = { .data1 = 0xa8d35f2d, 86 .data2 = 0xb30b, 87 .data3 = 0x454d, 88 .data4 = { 0xab, 0xf7, 0xd3, 89 0xd8, 0x48, 0x34, 90 0xab, 0x0c} }; 91 92 static const MSGUID logical_sector_guid = { .data1 = 0x8141bf1d, 93 .data2 = 0xa96f, 94 .data3 = 0x4709, 95 .data4 = { 0xba, 0x47, 0xf2, 96 0x33, 0xa8, 0xfa, 97 0xab, 0x5f} }; 98 99 /* Each parent type must have a valid GUID; this is for parent images 100 * of type 'VHDX'. If we were to allow e.g. a QCOW2 parent, we would 101 * need to make up our own QCOW2 GUID type */ 102 static const MSGUID parent_vhdx_guid = { .data1 = 0xb04aefb7, 103 .data2 = 0xd19e, 104 .data3 = 0x4a81, 105 .data4 = { 0xb7, 0x89, 0x25, 0xb8, 106 0xe9, 0x44, 0x59, 0x13} }; 107 108 109 #define META_FILE_PARAMETER_PRESENT 0x01 110 #define META_VIRTUAL_DISK_SIZE_PRESENT 0x02 111 #define META_PAGE_83_PRESENT 0x04 112 #define META_LOGICAL_SECTOR_SIZE_PRESENT 0x08 113 #define META_PHYS_SECTOR_SIZE_PRESENT 0x10 114 #define META_PARENT_LOCATOR_PRESENT 0x20 115 116 #define META_ALL_PRESENT \ 117 (META_FILE_PARAMETER_PRESENT | META_VIRTUAL_DISK_SIZE_PRESENT | \ 118 META_PAGE_83_PRESENT | META_LOGICAL_SECTOR_SIZE_PRESENT | \ 119 META_PHYS_SECTOR_SIZE_PRESENT) 120 121 122 typedef struct VHDXSectorInfo { 123 uint32_t bat_idx; /* BAT entry index */ 124 uint32_t sectors_avail; /* sectors available in payload block */ 125 uint32_t bytes_left; /* bytes left in the block after data to r/w */ 126 uint32_t bytes_avail; /* bytes available in payload block */ 127 uint64_t file_offset; /* absolute offset in bytes, in file */ 128 uint64_t block_offset; /* block offset, in bytes */ 129 } VHDXSectorInfo; 130 131 /* Calculates new checksum. 132 * 133 * Zero is substituted during crc calculation for the original crc field 134 * crc_offset: byte offset in buf of the buffer crc 135 * buf: buffer pointer 136 * size: size of buffer (must be > crc_offset+4) 137 * 138 * Note: The resulting checksum is in the CPU endianness, not necessarily 139 * in the file format endianness (LE). Any header export to disk should 140 * make sure that vhdx_header_le_export() is used to convert to the 141 * correct endianness 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 memcpy(buf + crc_offset, &crc, sizeof(crc)); 153 154 return crc; 155 } 156 157 uint32_t vhdx_checksum_calc(uint32_t crc, uint8_t *buf, size_t size, 158 int crc_offset) 159 { 160 uint32_t crc_new; 161 uint32_t crc_orig; 162 assert(buf != NULL); 163 164 if (crc_offset > 0) { 165 memcpy(&crc_orig, buf + crc_offset, sizeof(crc_orig)); 166 memset(buf + crc_offset, 0, sizeof(crc_orig)); 167 } 168 169 crc_new = crc32c(crc, buf, size); 170 if (crc_offset > 0) { 171 memcpy(buf + crc_offset, &crc_orig, sizeof(crc_orig)); 172 } 173 174 return crc_new; 175 } 176 177 /* Validates the checksum of the buffer, with an in-place CRC. 178 * 179 * Zero is substituted during crc calculation for the original crc field, 180 * and the crc field is restored afterwards. But the buffer will be modifed 181 * during the calculation, so this may not be not suitable for multi-threaded 182 * use. 183 * 184 * crc_offset: byte offset in buf of the buffer crc 185 * buf: buffer pointer 186 * size: size of buffer (must be > crc_offset+4) 187 * 188 * returns true if checksum is valid, false otherwise 189 */ 190 bool vhdx_checksum_is_valid(uint8_t *buf, size_t size, int crc_offset) 191 { 192 uint32_t crc_orig; 193 uint32_t crc; 194 195 assert(buf != NULL); 196 assert(size > (crc_offset + 4)); 197 198 memcpy(&crc_orig, buf + crc_offset, sizeof(crc_orig)); 199 crc_orig = le32_to_cpu(crc_orig); 200 201 crc = vhdx_checksum_calc(0xffffffff, buf, size, crc_offset); 202 203 return crc == crc_orig; 204 } 205 206 207 /* 208 * This generates a UUID that is compliant with the MS GUIDs used 209 * in the VHDX spec (and elsewhere). 210 */ 211 void vhdx_guid_generate(MSGUID *guid) 212 { 213 uuid_t uuid; 214 assert(guid != NULL); 215 216 uuid_generate(uuid); 217 memcpy(guid, uuid, sizeof(MSGUID)); 218 } 219 220 /* Check for region overlaps inside the VHDX image */ 221 static int vhdx_region_check(BDRVVHDXState *s, uint64_t start, uint64_t length) 222 { 223 int ret = 0; 224 uint64_t end; 225 VHDXRegionEntry *r; 226 227 end = start + length; 228 QLIST_FOREACH(r, &s->regions, entries) { 229 if (!((start >= r->end) || (end <= r->start))) { 230 ret = -EINVAL; 231 goto exit; 232 } 233 } 234 235 exit: 236 return ret; 237 } 238 239 /* Register a region for future checks */ 240 static void vhdx_region_register(BDRVVHDXState *s, 241 uint64_t start, uint64_t length) 242 { 243 VHDXRegionEntry *r; 244 245 r = g_malloc0(sizeof(*r)); 246 247 r->start = start; 248 r->end = start + length; 249 250 QLIST_INSERT_HEAD(&s->regions, r, entries); 251 } 252 253 /* Free all registered regions */ 254 static void vhdx_region_unregister_all(BDRVVHDXState *s) 255 { 256 VHDXRegionEntry *r, *r_next; 257 258 QLIST_FOREACH_SAFE(r, &s->regions, entries, r_next) { 259 QLIST_REMOVE(r, entries); 260 g_free(r); 261 } 262 } 263 264 static void vhdx_set_shift_bits(BDRVVHDXState *s) 265 { 266 s->logical_sector_size_bits = 31 - clz32(s->logical_sector_size); 267 s->sectors_per_block_bits = 31 - clz32(s->sectors_per_block); 268 s->chunk_ratio_bits = 63 - clz64(s->chunk_ratio); 269 s->block_size_bits = 31 - clz32(s->block_size); 270 } 271 272 /* 273 * Per the MS VHDX Specification, for every VHDX file: 274 * - The header section is fixed size - 1 MB 275 * - The header section is always the first "object" 276 * - The first 64KB of the header is the File Identifier 277 * - The first uint64 (8 bytes) is the VHDX Signature ("vhdxfile") 278 * - The following 512 bytes constitute a UTF-16 string identifiying the 279 * software that created the file, and is optional and diagnostic only. 280 * 281 * Therefore, we probe by looking for the vhdxfile signature "vhdxfile" 282 */ 283 static int vhdx_probe(const uint8_t *buf, int buf_size, const char *filename) 284 { 285 if (buf_size >= 8 && !memcmp(buf, "vhdxfile", 8)) { 286 return 100; 287 } 288 return 0; 289 } 290 291 /* 292 * Writes the header to the specified offset. 293 * 294 * This will optionally read in buffer data from disk (otherwise zero-fill), 295 * and then update the header checksum. Header is converted to proper 296 * endianness before being written to the specified file offset 297 */ 298 static int vhdx_write_header(BlockDriverState *bs_file, VHDXHeader *hdr, 299 uint64_t offset, bool read) 300 { 301 uint8_t *buffer = NULL; 302 int ret; 303 VHDXHeader header_le; 304 305 assert(bs_file != NULL); 306 assert(hdr != NULL); 307 308 /* the header checksum is not over just the packed size of VHDXHeader, 309 * but rather over the entire 'reserved' range for the header, which is 310 * 4KB (VHDX_HEADER_SIZE). */ 311 312 buffer = qemu_blockalign(bs_file, VHDX_HEADER_SIZE); 313 if (read) { 314 /* if true, we can't assume the extra reserved bytes are 0 */ 315 ret = bdrv_pread(bs_file, offset, buffer, VHDX_HEADER_SIZE); 316 if (ret < 0) { 317 goto exit; 318 } 319 } else { 320 memset(buffer, 0, VHDX_HEADER_SIZE); 321 } 322 323 /* overwrite the actual VHDXHeader portion */ 324 memcpy(buffer, hdr, sizeof(VHDXHeader)); 325 hdr->checksum = vhdx_update_checksum(buffer, VHDX_HEADER_SIZE, 326 offsetof(VHDXHeader, checksum)); 327 vhdx_header_le_export(hdr, &header_le); 328 ret = bdrv_pwrite_sync(bs_file, offset, &header_le, sizeof(VHDXHeader)); 329 330 exit: 331 qemu_vfree(buffer); 332 return ret; 333 } 334 335 /* Update the VHDX headers 336 * 337 * This follows the VHDX spec procedures for header updates. 338 * 339 * - non-current header is updated with largest sequence number 340 */ 341 static int vhdx_update_header(BlockDriverState *bs, BDRVVHDXState *s, 342 bool generate_data_write_guid, MSGUID *log_guid) 343 { 344 int ret = 0; 345 int hdr_idx = 0; 346 uint64_t header_offset = VHDX_HEADER1_OFFSET; 347 348 VHDXHeader *active_header; 349 VHDXHeader *inactive_header; 350 351 /* operate on the non-current header */ 352 if (s->curr_header == 0) { 353 hdr_idx = 1; 354 header_offset = VHDX_HEADER2_OFFSET; 355 } 356 357 active_header = s->headers[s->curr_header]; 358 inactive_header = s->headers[hdr_idx]; 359 360 inactive_header->sequence_number = active_header->sequence_number + 1; 361 362 /* a new file guid must be generated before any file write, including 363 * headers */ 364 inactive_header->file_write_guid = s->session_guid; 365 366 /* a new data guid only needs to be generated before any guest-visible 367 * writes (i.e. something observable via virtual disk read) */ 368 if (generate_data_write_guid) { 369 vhdx_guid_generate(&inactive_header->data_write_guid); 370 } 371 372 /* update the log guid if present */ 373 if (log_guid) { 374 inactive_header->log_guid = *log_guid; 375 } 376 377 ret = vhdx_write_header(bs->file, inactive_header, header_offset, true); 378 if (ret < 0) { 379 goto exit; 380 } 381 s->curr_header = hdr_idx; 382 383 exit: 384 return ret; 385 } 386 387 /* 388 * The VHDX spec calls for header updates to be performed twice, so that both 389 * the current and non-current header have valid info 390 */ 391 int vhdx_update_headers(BlockDriverState *bs, BDRVVHDXState *s, 392 bool generate_data_write_guid, MSGUID *log_guid) 393 { 394 int ret; 395 396 ret = vhdx_update_header(bs, s, generate_data_write_guid, log_guid); 397 if (ret < 0) { 398 return ret; 399 } 400 ret = vhdx_update_header(bs, s, generate_data_write_guid, log_guid); 401 return ret; 402 } 403 404 /* opens the specified header block from the VHDX file header section */ 405 static void vhdx_parse_header(BlockDriverState *bs, BDRVVHDXState *s, 406 Error **errp) 407 { 408 int ret; 409 VHDXHeader *header1; 410 VHDXHeader *header2; 411 bool h1_valid = false; 412 bool h2_valid = false; 413 uint64_t h1_seq = 0; 414 uint64_t h2_seq = 0; 415 uint8_t *buffer; 416 417 /* header1 & header2 are freed in vhdx_close() */ 418 header1 = qemu_blockalign(bs, sizeof(VHDXHeader)); 419 header2 = qemu_blockalign(bs, sizeof(VHDXHeader)); 420 421 buffer = qemu_blockalign(bs, VHDX_HEADER_SIZE); 422 423 s->headers[0] = header1; 424 s->headers[1] = header2; 425 426 /* We have to read the whole VHDX_HEADER_SIZE instead of 427 * sizeof(VHDXHeader), because the checksum is over the whole 428 * region */ 429 ret = bdrv_pread(bs->file, VHDX_HEADER1_OFFSET, buffer, VHDX_HEADER_SIZE); 430 if (ret < 0) { 431 goto fail; 432 } 433 /* copy over just the relevant portion that we need */ 434 memcpy(header1, buffer, sizeof(VHDXHeader)); 435 vhdx_header_le_import(header1); 436 437 if (vhdx_checksum_is_valid(buffer, VHDX_HEADER_SIZE, 4) && 438 !memcmp(&header1->signature, "head", 4) && 439 header1->version == 1) { 440 h1_seq = header1->sequence_number; 441 h1_valid = true; 442 } 443 444 ret = bdrv_pread(bs->file, VHDX_HEADER2_OFFSET, buffer, VHDX_HEADER_SIZE); 445 if (ret < 0) { 446 goto fail; 447 } 448 /* copy over just the relevant portion that we need */ 449 memcpy(header2, buffer, sizeof(VHDXHeader)); 450 vhdx_header_le_import(header2); 451 452 if (vhdx_checksum_is_valid(buffer, VHDX_HEADER_SIZE, 4) && 453 !memcmp(&header2->signature, "head", 4) && 454 header2->version == 1) { 455 h2_seq = header2->sequence_number; 456 h2_valid = true; 457 } 458 459 /* If there is only 1 valid header (or no valid headers), we 460 * don't care what the sequence numbers are */ 461 if (h1_valid && !h2_valid) { 462 s->curr_header = 0; 463 } else if (!h1_valid && h2_valid) { 464 s->curr_header = 1; 465 } else if (!h1_valid && !h2_valid) { 466 goto fail; 467 } else { 468 /* If both headers are valid, then we choose the active one by the 469 * highest sequence number. If the sequence numbers are equal, that is 470 * invalid */ 471 if (h1_seq > h2_seq) { 472 s->curr_header = 0; 473 } else if (h2_seq > h1_seq) { 474 s->curr_header = 1; 475 } else { 476 goto fail; 477 } 478 } 479 480 vhdx_region_register(s, s->headers[s->curr_header]->log_offset, 481 s->headers[s->curr_header]->log_length); 482 goto exit; 483 484 fail: 485 error_setg_errno(errp, -ret, "No valid VHDX header found"); 486 qemu_vfree(header1); 487 qemu_vfree(header2); 488 s->headers[0] = NULL; 489 s->headers[1] = NULL; 490 exit: 491 qemu_vfree(buffer); 492 } 493 494 495 static int vhdx_open_region_tables(BlockDriverState *bs, BDRVVHDXState *s) 496 { 497 int ret = 0; 498 uint8_t *buffer; 499 int offset = 0; 500 VHDXRegionTableEntry rt_entry; 501 uint32_t i; 502 bool bat_rt_found = false; 503 bool metadata_rt_found = false; 504 505 /* We have to read the whole 64KB block, because the crc32 is over the 506 * whole block */ 507 buffer = qemu_blockalign(bs, VHDX_HEADER_BLOCK_SIZE); 508 509 ret = bdrv_pread(bs->file, VHDX_REGION_TABLE_OFFSET, buffer, 510 VHDX_HEADER_BLOCK_SIZE); 511 if (ret < 0) { 512 goto fail; 513 } 514 memcpy(&s->rt, buffer, sizeof(s->rt)); 515 vhdx_region_header_le_import(&s->rt); 516 offset += sizeof(s->rt); 517 518 if (!vhdx_checksum_is_valid(buffer, VHDX_HEADER_BLOCK_SIZE, 4) || 519 memcmp(&s->rt.signature, "regi", 4)) { 520 ret = -EINVAL; 521 goto fail; 522 } 523 524 /* Per spec, maximum region table entry count is 2047 */ 525 if (s->rt.entry_count > 2047) { 526 ret = -EINVAL; 527 goto fail; 528 } 529 530 for (i = 0; i < s->rt.entry_count; i++) { 531 memcpy(&rt_entry, buffer + offset, sizeof(rt_entry)); 532 offset += sizeof(rt_entry); 533 534 vhdx_region_entry_le_import(&rt_entry); 535 536 /* check for region overlap between these entries, and any 537 * other memory regions in the file */ 538 ret = vhdx_region_check(s, rt_entry.file_offset, rt_entry.length); 539 if (ret < 0) { 540 goto fail; 541 } 542 543 vhdx_region_register(s, rt_entry.file_offset, rt_entry.length); 544 545 /* see if we recognize the entry */ 546 if (guid_eq(rt_entry.guid, bat_guid)) { 547 /* must be unique; if we have already found it this is invalid */ 548 if (bat_rt_found) { 549 ret = -EINVAL; 550 goto fail; 551 } 552 bat_rt_found = true; 553 s->bat_rt = rt_entry; 554 continue; 555 } 556 557 if (guid_eq(rt_entry.guid, metadata_guid)) { 558 /* must be unique; if we have already found it this is invalid */ 559 if (metadata_rt_found) { 560 ret = -EINVAL; 561 goto fail; 562 } 563 metadata_rt_found = true; 564 s->metadata_rt = rt_entry; 565 continue; 566 } 567 568 if (rt_entry.data_bits & VHDX_REGION_ENTRY_REQUIRED) { 569 /* cannot read vhdx file - required region table entry that 570 * we do not understand. per spec, we must fail to open */ 571 ret = -ENOTSUP; 572 goto fail; 573 } 574 } 575 576 if (!bat_rt_found || !metadata_rt_found) { 577 ret = -EINVAL; 578 goto fail; 579 } 580 581 ret = 0; 582 583 fail: 584 qemu_vfree(buffer); 585 return ret; 586 } 587 588 589 590 /* Metadata initial parser 591 * 592 * This loads all the metadata entry fields. This may cause additional 593 * fields to be processed (e.g. parent locator, etc..). 594 * 595 * There are 5 Metadata items that are always required: 596 * - File Parameters (block size, has a parent) 597 * - Virtual Disk Size (size, in bytes, of the virtual drive) 598 * - Page 83 Data (scsi page 83 guid) 599 * - Logical Sector Size (logical sector size in bytes, either 512 or 600 * 4096. We only support 512 currently) 601 * - Physical Sector Size (512 or 4096) 602 * 603 * Also, if the File Parameters indicate this is a differencing file, 604 * we must also look for the Parent Locator metadata item. 605 */ 606 static int vhdx_parse_metadata(BlockDriverState *bs, BDRVVHDXState *s) 607 { 608 int ret = 0; 609 uint8_t *buffer; 610 int offset = 0; 611 uint32_t i = 0; 612 VHDXMetadataTableEntry md_entry; 613 614 buffer = qemu_blockalign(bs, VHDX_METADATA_TABLE_MAX_SIZE); 615 616 ret = bdrv_pread(bs->file, s->metadata_rt.file_offset, buffer, 617 VHDX_METADATA_TABLE_MAX_SIZE); 618 if (ret < 0) { 619 goto exit; 620 } 621 memcpy(&s->metadata_hdr, buffer, sizeof(s->metadata_hdr)); 622 offset += sizeof(s->metadata_hdr); 623 624 vhdx_metadata_header_le_import(&s->metadata_hdr); 625 626 if (memcmp(&s->metadata_hdr.signature, "metadata", 8)) { 627 ret = -EINVAL; 628 goto exit; 629 } 630 631 s->metadata_entries.present = 0; 632 633 if ((s->metadata_hdr.entry_count * sizeof(md_entry)) > 634 (VHDX_METADATA_TABLE_MAX_SIZE - offset)) { 635 ret = -EINVAL; 636 goto exit; 637 } 638 639 for (i = 0; i < s->metadata_hdr.entry_count; i++) { 640 memcpy(&md_entry, buffer + offset, sizeof(md_entry)); 641 offset += sizeof(md_entry); 642 643 vhdx_metadata_entry_le_import(&md_entry); 644 645 if (guid_eq(md_entry.item_id, file_param_guid)) { 646 if (s->metadata_entries.present & META_FILE_PARAMETER_PRESENT) { 647 ret = -EINVAL; 648 goto exit; 649 } 650 s->metadata_entries.file_parameters_entry = md_entry; 651 s->metadata_entries.present |= META_FILE_PARAMETER_PRESENT; 652 continue; 653 } 654 655 if (guid_eq(md_entry.item_id, virtual_size_guid)) { 656 if (s->metadata_entries.present & META_VIRTUAL_DISK_SIZE_PRESENT) { 657 ret = -EINVAL; 658 goto exit; 659 } 660 s->metadata_entries.virtual_disk_size_entry = md_entry; 661 s->metadata_entries.present |= META_VIRTUAL_DISK_SIZE_PRESENT; 662 continue; 663 } 664 665 if (guid_eq(md_entry.item_id, page83_guid)) { 666 if (s->metadata_entries.present & META_PAGE_83_PRESENT) { 667 ret = -EINVAL; 668 goto exit; 669 } 670 s->metadata_entries.page83_data_entry = md_entry; 671 s->metadata_entries.present |= META_PAGE_83_PRESENT; 672 continue; 673 } 674 675 if (guid_eq(md_entry.item_id, logical_sector_guid)) { 676 if (s->metadata_entries.present & 677 META_LOGICAL_SECTOR_SIZE_PRESENT) { 678 ret = -EINVAL; 679 goto exit; 680 } 681 s->metadata_entries.logical_sector_size_entry = md_entry; 682 s->metadata_entries.present |= META_LOGICAL_SECTOR_SIZE_PRESENT; 683 continue; 684 } 685 686 if (guid_eq(md_entry.item_id, phys_sector_guid)) { 687 if (s->metadata_entries.present & META_PHYS_SECTOR_SIZE_PRESENT) { 688 ret = -EINVAL; 689 goto exit; 690 } 691 s->metadata_entries.phys_sector_size_entry = md_entry; 692 s->metadata_entries.present |= META_PHYS_SECTOR_SIZE_PRESENT; 693 continue; 694 } 695 696 if (guid_eq(md_entry.item_id, parent_locator_guid)) { 697 if (s->metadata_entries.present & META_PARENT_LOCATOR_PRESENT) { 698 ret = -EINVAL; 699 goto exit; 700 } 701 s->metadata_entries.parent_locator_entry = md_entry; 702 s->metadata_entries.present |= META_PARENT_LOCATOR_PRESENT; 703 continue; 704 } 705 706 if (md_entry.data_bits & VHDX_META_FLAGS_IS_REQUIRED) { 707 /* cannot read vhdx file - required region table entry that 708 * we do not understand. per spec, we must fail to open */ 709 ret = -ENOTSUP; 710 goto exit; 711 } 712 } 713 714 if (s->metadata_entries.present != META_ALL_PRESENT) { 715 ret = -ENOTSUP; 716 goto exit; 717 } 718 719 ret = bdrv_pread(bs->file, 720 s->metadata_entries.file_parameters_entry.offset 721 + s->metadata_rt.file_offset, 722 &s->params, 723 sizeof(s->params)); 724 725 if (ret < 0) { 726 goto exit; 727 } 728 729 le32_to_cpus(&s->params.block_size); 730 le32_to_cpus(&s->params.data_bits); 731 732 733 /* We now have the file parameters, so we can tell if this is a 734 * differencing file (i.e.. has_parent), is dynamic or fixed 735 * sized (leave_blocks_allocated), and the block size */ 736 737 /* The parent locator required iff the file parameters has_parent set */ 738 if (s->params.data_bits & VHDX_PARAMS_HAS_PARENT) { 739 if (s->metadata_entries.present & META_PARENT_LOCATOR_PRESENT) { 740 /* TODO: parse parent locator fields */ 741 ret = -ENOTSUP; /* temp, until differencing files are supported */ 742 goto exit; 743 } else { 744 /* if has_parent is set, but there is not parent locator present, 745 * then that is an invalid combination */ 746 ret = -EINVAL; 747 goto exit; 748 } 749 } 750 751 /* determine virtual disk size, logical sector size, 752 * and phys sector size */ 753 754 ret = bdrv_pread(bs->file, 755 s->metadata_entries.virtual_disk_size_entry.offset 756 + s->metadata_rt.file_offset, 757 &s->virtual_disk_size, 758 sizeof(uint64_t)); 759 if (ret < 0) { 760 goto exit; 761 } 762 ret = bdrv_pread(bs->file, 763 s->metadata_entries.logical_sector_size_entry.offset 764 + s->metadata_rt.file_offset, 765 &s->logical_sector_size, 766 sizeof(uint32_t)); 767 if (ret < 0) { 768 goto exit; 769 } 770 ret = bdrv_pread(bs->file, 771 s->metadata_entries.phys_sector_size_entry.offset 772 + s->metadata_rt.file_offset, 773 &s->physical_sector_size, 774 sizeof(uint32_t)); 775 if (ret < 0) { 776 goto exit; 777 } 778 779 le64_to_cpus(&s->virtual_disk_size); 780 le32_to_cpus(&s->logical_sector_size); 781 le32_to_cpus(&s->physical_sector_size); 782 783 if (s->params.block_size < VHDX_BLOCK_SIZE_MIN || 784 s->params.block_size > VHDX_BLOCK_SIZE_MAX) { 785 ret = -EINVAL; 786 goto exit; 787 } 788 789 /* only 2 supported sector sizes */ 790 if (s->logical_sector_size != 512 && s->logical_sector_size != 4096) { 791 ret = -EINVAL; 792 goto exit; 793 } 794 795 /* Both block_size and sector_size are guaranteed powers of 2, below. 796 Due to range checks above, s->sectors_per_block can never be < 256 */ 797 s->sectors_per_block = s->params.block_size / s->logical_sector_size; 798 s->chunk_ratio = (VHDX_MAX_SECTORS_PER_BLOCK) * 799 (uint64_t)s->logical_sector_size / 800 (uint64_t)s->params.block_size; 801 802 /* These values are ones we will want to use for division / multiplication 803 * later on, and they are all guaranteed (per the spec) to be powers of 2, 804 * so we can take advantage of that for shift operations during 805 * reads/writes */ 806 if (s->logical_sector_size & (s->logical_sector_size - 1)) { 807 ret = -EINVAL; 808 goto exit; 809 } 810 if (s->sectors_per_block & (s->sectors_per_block - 1)) { 811 ret = -EINVAL; 812 goto exit; 813 } 814 if (s->chunk_ratio & (s->chunk_ratio - 1)) { 815 ret = -EINVAL; 816 goto exit; 817 } 818 s->block_size = s->params.block_size; 819 if (s->block_size & (s->block_size - 1)) { 820 ret = -EINVAL; 821 goto exit; 822 } 823 824 vhdx_set_shift_bits(s); 825 826 ret = 0; 827 828 exit: 829 qemu_vfree(buffer); 830 return ret; 831 } 832 833 /* 834 * Calculate the number of BAT entries, including sector 835 * bitmap entries. 836 */ 837 static void vhdx_calc_bat_entries(BDRVVHDXState *s) 838 { 839 uint32_t data_blocks_cnt, bitmap_blocks_cnt; 840 841 data_blocks_cnt = s->virtual_disk_size >> s->block_size_bits; 842 if (s->virtual_disk_size - (data_blocks_cnt << s->block_size_bits)) { 843 data_blocks_cnt++; 844 } 845 bitmap_blocks_cnt = data_blocks_cnt >> s->chunk_ratio_bits; 846 if (data_blocks_cnt - (bitmap_blocks_cnt << s->chunk_ratio_bits)) { 847 bitmap_blocks_cnt++; 848 } 849 850 if (s->parent_entries) { 851 s->bat_entries = bitmap_blocks_cnt * (s->chunk_ratio + 1); 852 } else { 853 s->bat_entries = data_blocks_cnt + 854 ((data_blocks_cnt - 1) >> s->chunk_ratio_bits); 855 } 856 857 } 858 859 static void vhdx_close(BlockDriverState *bs) 860 { 861 BDRVVHDXState *s = bs->opaque; 862 qemu_vfree(s->headers[0]); 863 s->headers[0] = NULL; 864 qemu_vfree(s->headers[1]); 865 s->headers[1] = NULL; 866 qemu_vfree(s->bat); 867 s->bat = NULL; 868 qemu_vfree(s->parent_entries); 869 s->parent_entries = NULL; 870 migrate_del_blocker(s->migration_blocker); 871 error_free(s->migration_blocker); 872 qemu_vfree(s->log.hdr); 873 s->log.hdr = NULL; 874 vhdx_region_unregister_all(s); 875 } 876 877 static int vhdx_open(BlockDriverState *bs, QDict *options, int flags, 878 Error **errp) 879 { 880 BDRVVHDXState *s = bs->opaque; 881 int ret = 0; 882 uint32_t i; 883 uint64_t signature; 884 Error *local_err = NULL; 885 886 s->bat = NULL; 887 s->first_visible_write = true; 888 889 qemu_co_mutex_init(&s->lock); 890 QLIST_INIT(&s->regions); 891 892 /* validate the file signature */ 893 ret = bdrv_pread(bs->file, 0, &signature, sizeof(uint64_t)); 894 if (ret < 0) { 895 goto fail; 896 } 897 if (memcmp(&signature, "vhdxfile", 8)) { 898 ret = -EINVAL; 899 goto fail; 900 } 901 902 /* This is used for any header updates, for the file_write_guid. 903 * The spec dictates that a new value should be used for the first 904 * header update */ 905 vhdx_guid_generate(&s->session_guid); 906 907 vhdx_parse_header(bs, s, &local_err); 908 if (local_err != NULL) { 909 error_propagate(errp, local_err); 910 ret = -EINVAL; 911 goto fail; 912 } 913 914 ret = vhdx_parse_log(bs, s, &s->log_replayed_on_open, errp); 915 if (ret < 0) { 916 goto fail; 917 } 918 919 ret = vhdx_open_region_tables(bs, s); 920 if (ret < 0) { 921 goto fail; 922 } 923 924 ret = vhdx_parse_metadata(bs, s); 925 if (ret < 0) { 926 goto fail; 927 } 928 929 s->block_size = s->params.block_size; 930 931 /* the VHDX spec dictates that virtual_disk_size is always a multiple of 932 * logical_sector_size */ 933 bs->total_sectors = s->virtual_disk_size >> s->logical_sector_size_bits; 934 935 vhdx_calc_bat_entries(s); 936 937 s->bat_offset = s->bat_rt.file_offset; 938 939 if (s->bat_entries > s->bat_rt.length / sizeof(VHDXBatEntry)) { 940 /* BAT allocation is not large enough for all entries */ 941 ret = -EINVAL; 942 goto fail; 943 } 944 945 /* s->bat is freed in vhdx_close() */ 946 s->bat = qemu_blockalign(bs, s->bat_rt.length); 947 948 ret = bdrv_pread(bs->file, s->bat_offset, s->bat, s->bat_rt.length); 949 if (ret < 0) { 950 goto fail; 951 } 952 953 uint64_t payblocks = s->chunk_ratio; 954 /* endian convert, and verify populated BAT field file offsets against 955 * region table and log entries */ 956 for (i = 0; i < s->bat_entries; i++) { 957 le64_to_cpus(&s->bat[i]); 958 if (payblocks--) { 959 /* payload bat entries */ 960 if ((s->bat[i] & VHDX_BAT_STATE_BIT_MASK) == 961 PAYLOAD_BLOCK_FULLY_PRESENT) { 962 ret = vhdx_region_check(s, s->bat[i] & VHDX_BAT_FILE_OFF_MASK, 963 s->block_size); 964 if (ret < 0) { 965 goto fail; 966 } 967 } 968 } else { 969 payblocks = s->chunk_ratio; 970 /* Once differencing files are supported, verify sector bitmap 971 * blocks here */ 972 } 973 } 974 975 if (flags & BDRV_O_RDWR) { 976 ret = vhdx_update_headers(bs, s, false, NULL); 977 if (ret < 0) { 978 goto fail; 979 } 980 } 981 982 /* TODO: differencing files */ 983 984 /* Disable migration when VHDX images are used */ 985 error_set(&s->migration_blocker, 986 QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED, 987 "vhdx", bs->device_name, "live migration"); 988 migrate_add_blocker(s->migration_blocker); 989 990 return 0; 991 fail: 992 vhdx_close(bs); 993 return ret; 994 } 995 996 static int vhdx_reopen_prepare(BDRVReopenState *state, 997 BlockReopenQueue *queue, Error **errp) 998 { 999 return 0; 1000 } 1001 1002 1003 /* 1004 * Perform sector to block offset translations, to get various 1005 * sector and file offsets into the image. See VHDXSectorInfo 1006 */ 1007 static void vhdx_block_translate(BDRVVHDXState *s, int64_t sector_num, 1008 int nb_sectors, VHDXSectorInfo *sinfo) 1009 { 1010 uint32_t block_offset; 1011 1012 sinfo->bat_idx = sector_num >> s->sectors_per_block_bits; 1013 /* effectively a modulo - this gives us the offset into the block 1014 * (in sector sizes) for our sector number */ 1015 block_offset = sector_num - (sinfo->bat_idx << s->sectors_per_block_bits); 1016 /* the chunk ratio gives us the interleaving of the sector 1017 * bitmaps, so we need to advance our page block index by the 1018 * sector bitmaps entry number */ 1019 sinfo->bat_idx += sinfo->bat_idx >> s->chunk_ratio_bits; 1020 1021 /* the number of sectors we can read/write in this cycle */ 1022 sinfo->sectors_avail = s->sectors_per_block - block_offset; 1023 1024 sinfo->bytes_left = sinfo->sectors_avail << s->logical_sector_size_bits; 1025 1026 if (sinfo->sectors_avail > nb_sectors) { 1027 sinfo->sectors_avail = nb_sectors; 1028 } 1029 1030 sinfo->bytes_avail = sinfo->sectors_avail << s->logical_sector_size_bits; 1031 1032 sinfo->file_offset = s->bat[sinfo->bat_idx] & VHDX_BAT_FILE_OFF_MASK; 1033 1034 sinfo->block_offset = block_offset << s->logical_sector_size_bits; 1035 1036 /* The file offset must be past the header section, so must be > 0 */ 1037 if (sinfo->file_offset == 0) { 1038 return; 1039 } 1040 1041 /* block offset is the offset in vhdx logical sectors, in 1042 * the payload data block. Convert that to a byte offset 1043 * in the block, and add in the payload data block offset 1044 * in the file, in bytes, to get the final read address */ 1045 1046 sinfo->file_offset += sinfo->block_offset; 1047 } 1048 1049 1050 static int vhdx_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) 1051 { 1052 BDRVVHDXState *s = bs->opaque; 1053 1054 bdi->cluster_size = s->block_size; 1055 1056 bdi->unallocated_blocks_are_zero = 1057 (s->params.data_bits & VHDX_PARAMS_HAS_PARENT) == 0; 1058 1059 return 0; 1060 } 1061 1062 1063 static coroutine_fn int vhdx_co_readv(BlockDriverState *bs, int64_t sector_num, 1064 int nb_sectors, QEMUIOVector *qiov) 1065 { 1066 BDRVVHDXState *s = bs->opaque; 1067 int ret = 0; 1068 VHDXSectorInfo sinfo; 1069 uint64_t bytes_done = 0; 1070 QEMUIOVector hd_qiov; 1071 1072 qemu_iovec_init(&hd_qiov, qiov->niov); 1073 1074 qemu_co_mutex_lock(&s->lock); 1075 1076 while (nb_sectors > 0) { 1077 /* We are a differencing file, so we need to inspect the sector bitmap 1078 * to see if we have the data or not */ 1079 if (s->params.data_bits & VHDX_PARAMS_HAS_PARENT) { 1080 /* not supported yet */ 1081 ret = -ENOTSUP; 1082 goto exit; 1083 } else { 1084 vhdx_block_translate(s, sector_num, nb_sectors, &sinfo); 1085 1086 qemu_iovec_reset(&hd_qiov); 1087 qemu_iovec_concat(&hd_qiov, qiov, bytes_done, sinfo.bytes_avail); 1088 1089 /* check the payload block state */ 1090 switch (s->bat[sinfo.bat_idx] & VHDX_BAT_STATE_BIT_MASK) { 1091 case PAYLOAD_BLOCK_NOT_PRESENT: /* fall through */ 1092 case PAYLOAD_BLOCK_UNDEFINED: /* fall through */ 1093 case PAYLOAD_BLOCK_UNMAPPED: /* fall through */ 1094 case PAYLOAD_BLOCK_ZERO: 1095 /* return zero */ 1096 qemu_iovec_memset(&hd_qiov, 0, 0, sinfo.bytes_avail); 1097 break; 1098 case PAYLOAD_BLOCK_FULLY_PRESENT: 1099 qemu_co_mutex_unlock(&s->lock); 1100 ret = bdrv_co_readv(bs->file, 1101 sinfo.file_offset >> BDRV_SECTOR_BITS, 1102 sinfo.sectors_avail, &hd_qiov); 1103 qemu_co_mutex_lock(&s->lock); 1104 if (ret < 0) { 1105 goto exit; 1106 } 1107 break; 1108 case PAYLOAD_BLOCK_PARTIALLY_PRESENT: 1109 /* we don't yet support difference files, fall through 1110 * to error */ 1111 default: 1112 ret = -EIO; 1113 goto exit; 1114 break; 1115 } 1116 nb_sectors -= sinfo.sectors_avail; 1117 sector_num += sinfo.sectors_avail; 1118 bytes_done += sinfo.bytes_avail; 1119 } 1120 } 1121 ret = 0; 1122 exit: 1123 qemu_co_mutex_unlock(&s->lock); 1124 qemu_iovec_destroy(&hd_qiov); 1125 return ret; 1126 } 1127 1128 /* 1129 * Allocate a new payload block at the end of the file. 1130 * 1131 * Allocation will happen at 1MB alignment inside the file 1132 * 1133 * Returns the file offset start of the new payload block 1134 */ 1135 static int vhdx_allocate_block(BlockDriverState *bs, BDRVVHDXState *s, 1136 uint64_t *new_offset) 1137 { 1138 *new_offset = bdrv_getlength(bs->file); 1139 1140 /* per the spec, the address for a block is in units of 1MB */ 1141 *new_offset = ROUND_UP(*new_offset, 1024 * 1024); 1142 1143 return bdrv_truncate(bs->file, *new_offset + s->block_size); 1144 } 1145 1146 /* 1147 * Update the BAT table entry with the new file offset, and the new entry 1148 * state */ 1149 static void vhdx_update_bat_table_entry(BlockDriverState *bs, BDRVVHDXState *s, 1150 VHDXSectorInfo *sinfo, 1151 uint64_t *bat_entry_le, 1152 uint64_t *bat_offset, int state) 1153 { 1154 /* The BAT entry is a uint64, with 44 bits for the file offset in units of 1155 * 1MB, and 3 bits for the block state. */ 1156 s->bat[sinfo->bat_idx] = sinfo->file_offset; 1157 1158 s->bat[sinfo->bat_idx] |= state & VHDX_BAT_STATE_BIT_MASK; 1159 1160 *bat_entry_le = cpu_to_le64(s->bat[sinfo->bat_idx]); 1161 *bat_offset = s->bat_offset + sinfo->bat_idx * sizeof(VHDXBatEntry); 1162 1163 } 1164 1165 /* Per the spec, on the first write of guest-visible data to the file the 1166 * data write guid must be updated in the header */ 1167 int vhdx_user_visible_write(BlockDriverState *bs, BDRVVHDXState *s) 1168 { 1169 int ret = 0; 1170 if (s->first_visible_write) { 1171 s->first_visible_write = false; 1172 ret = vhdx_update_headers(bs, s, true, NULL); 1173 } 1174 return ret; 1175 } 1176 1177 static coroutine_fn int vhdx_co_writev(BlockDriverState *bs, int64_t sector_num, 1178 int nb_sectors, QEMUIOVector *qiov) 1179 { 1180 int ret = -ENOTSUP; 1181 BDRVVHDXState *s = bs->opaque; 1182 VHDXSectorInfo sinfo; 1183 uint64_t bytes_done = 0; 1184 uint64_t bat_entry = 0; 1185 uint64_t bat_entry_offset = 0; 1186 QEMUIOVector hd_qiov; 1187 struct iovec iov1 = { 0 }; 1188 struct iovec iov2 = { 0 }; 1189 int sectors_to_write; 1190 int bat_state; 1191 uint64_t bat_prior_offset = 0; 1192 bool bat_update = false; 1193 1194 qemu_iovec_init(&hd_qiov, qiov->niov); 1195 1196 qemu_co_mutex_lock(&s->lock); 1197 1198 ret = vhdx_user_visible_write(bs, s); 1199 if (ret < 0) { 1200 goto exit; 1201 } 1202 1203 while (nb_sectors > 0) { 1204 bool use_zero_buffers = false; 1205 bat_update = false; 1206 if (s->params.data_bits & VHDX_PARAMS_HAS_PARENT) { 1207 /* not supported yet */ 1208 ret = -ENOTSUP; 1209 goto exit; 1210 } else { 1211 vhdx_block_translate(s, sector_num, nb_sectors, &sinfo); 1212 sectors_to_write = sinfo.sectors_avail; 1213 1214 qemu_iovec_reset(&hd_qiov); 1215 /* check the payload block state */ 1216 bat_state = s->bat[sinfo.bat_idx] & VHDX_BAT_STATE_BIT_MASK; 1217 switch (bat_state) { 1218 case PAYLOAD_BLOCK_ZERO: 1219 /* in this case, we need to preserve zero writes for 1220 * data that is not part of this write, so we must pad 1221 * the rest of the buffer to zeroes */ 1222 1223 /* if we are on a posix system with ftruncate() that extends 1224 * a file, then it is zero-filled for us. On Win32, the raw 1225 * layer uses SetFilePointer and SetFileEnd, which does not 1226 * zero fill AFAIK */ 1227 1228 /* Queue another write of zero buffers if the underlying file 1229 * does not zero-fill on file extension */ 1230 1231 if (bdrv_has_zero_init(bs->file) == 0) { 1232 use_zero_buffers = true; 1233 1234 /* zero fill the front, if any */ 1235 if (sinfo.block_offset) { 1236 iov1.iov_len = sinfo.block_offset; 1237 iov1.iov_base = qemu_blockalign(bs, iov1.iov_len); 1238 memset(iov1.iov_base, 0, iov1.iov_len); 1239 qemu_iovec_concat_iov(&hd_qiov, &iov1, 1, 0, 1240 sinfo.block_offset); 1241 sectors_to_write += iov1.iov_len >> BDRV_SECTOR_BITS; 1242 } 1243 1244 /* our actual data */ 1245 qemu_iovec_concat(&hd_qiov, qiov, bytes_done, 1246 sinfo.bytes_avail); 1247 1248 /* zero fill the back, if any */ 1249 if ((sinfo.bytes_avail - sinfo.block_offset) < 1250 s->block_size) { 1251 iov2.iov_len = s->block_size - 1252 (sinfo.bytes_avail + sinfo.block_offset); 1253 iov2.iov_base = qemu_blockalign(bs, iov2.iov_len); 1254 memset(iov2.iov_base, 0, iov2.iov_len); 1255 qemu_iovec_concat_iov(&hd_qiov, &iov2, 1, 0, 1256 sinfo.block_offset); 1257 sectors_to_write += iov2.iov_len >> BDRV_SECTOR_BITS; 1258 } 1259 } 1260 1261 /* fall through */ 1262 case PAYLOAD_BLOCK_NOT_PRESENT: /* fall through */ 1263 case PAYLOAD_BLOCK_UNMAPPED: /* fall through */ 1264 case PAYLOAD_BLOCK_UNDEFINED: /* fall through */ 1265 bat_prior_offset = sinfo.file_offset; 1266 ret = vhdx_allocate_block(bs, s, &sinfo.file_offset); 1267 if (ret < 0) { 1268 goto exit; 1269 } 1270 /* once we support differencing files, this may also be 1271 * partially present */ 1272 /* update block state to the newly specified state */ 1273 vhdx_update_bat_table_entry(bs, s, &sinfo, &bat_entry, 1274 &bat_entry_offset, 1275 PAYLOAD_BLOCK_FULLY_PRESENT); 1276 bat_update = true; 1277 /* since we just allocated a block, file_offset is the 1278 * beginning of the payload block. It needs to be the 1279 * write address, which includes the offset into the block */ 1280 if (!use_zero_buffers) { 1281 sinfo.file_offset += sinfo.block_offset; 1282 } 1283 /* fall through */ 1284 case PAYLOAD_BLOCK_FULLY_PRESENT: 1285 /* if the file offset address is in the header zone, 1286 * there is a problem */ 1287 if (sinfo.file_offset < (1024 * 1024)) { 1288 ret = -EFAULT; 1289 goto error_bat_restore; 1290 } 1291 1292 if (!use_zero_buffers) { 1293 qemu_iovec_concat(&hd_qiov, qiov, bytes_done, 1294 sinfo.bytes_avail); 1295 } 1296 /* block exists, so we can just overwrite it */ 1297 qemu_co_mutex_unlock(&s->lock); 1298 ret = bdrv_co_writev(bs->file, 1299 sinfo.file_offset >> BDRV_SECTOR_BITS, 1300 sectors_to_write, &hd_qiov); 1301 qemu_co_mutex_lock(&s->lock); 1302 if (ret < 0) { 1303 goto error_bat_restore; 1304 } 1305 break; 1306 case PAYLOAD_BLOCK_PARTIALLY_PRESENT: 1307 /* we don't yet support difference files, fall through 1308 * to error */ 1309 default: 1310 ret = -EIO; 1311 goto exit; 1312 break; 1313 } 1314 1315 if (bat_update) { 1316 /* this will update the BAT entry into the log journal, and 1317 * then flush the log journal out to disk */ 1318 ret = vhdx_log_write_and_flush(bs, s, &bat_entry, 1319 sizeof(VHDXBatEntry), 1320 bat_entry_offset); 1321 if (ret < 0) { 1322 goto exit; 1323 } 1324 } 1325 1326 nb_sectors -= sinfo.sectors_avail; 1327 sector_num += sinfo.sectors_avail; 1328 bytes_done += sinfo.bytes_avail; 1329 1330 } 1331 } 1332 1333 goto exit; 1334 1335 error_bat_restore: 1336 if (bat_update) { 1337 /* keep metadata in sync, and restore the bat entry state 1338 * if error. */ 1339 sinfo.file_offset = bat_prior_offset; 1340 vhdx_update_bat_table_entry(bs, s, &sinfo, &bat_entry, 1341 &bat_entry_offset, bat_state); 1342 } 1343 exit: 1344 qemu_vfree(iov1.iov_base); 1345 qemu_vfree(iov2.iov_base); 1346 qemu_co_mutex_unlock(&s->lock); 1347 qemu_iovec_destroy(&hd_qiov); 1348 return ret; 1349 } 1350 1351 1352 1353 /* 1354 * Create VHDX Headers 1355 * 1356 * There are 2 headers, and the highest sequence number will represent 1357 * the active header 1358 */ 1359 static int vhdx_create_new_headers(BlockDriverState *bs, uint64_t image_size, 1360 uint32_t log_size) 1361 { 1362 int ret = 0; 1363 VHDXHeader *hdr = NULL; 1364 1365 hdr = g_malloc0(sizeof(VHDXHeader)); 1366 1367 hdr->signature = VHDX_HEADER_SIGNATURE; 1368 hdr->sequence_number = g_random_int(); 1369 hdr->log_version = 0; 1370 hdr->version = 1; 1371 hdr->log_length = log_size; 1372 hdr->log_offset = VHDX_HEADER_SECTION_END; 1373 vhdx_guid_generate(&hdr->file_write_guid); 1374 vhdx_guid_generate(&hdr->data_write_guid); 1375 1376 ret = vhdx_write_header(bs, hdr, VHDX_HEADER1_OFFSET, false); 1377 if (ret < 0) { 1378 goto exit; 1379 } 1380 hdr->sequence_number++; 1381 ret = vhdx_write_header(bs, hdr, VHDX_HEADER2_OFFSET, false); 1382 if (ret < 0) { 1383 goto exit; 1384 } 1385 1386 exit: 1387 g_free(hdr); 1388 return ret; 1389 } 1390 1391 1392 /* 1393 * Create the Metadata entries. 1394 * 1395 * For more details on the entries, see section 3.5 (pg 29) in the 1396 * VHDX 1.00 specification. 1397 * 1398 * We support 5 metadata entries (all required by spec): 1399 * File Parameters, 1400 * Virtual Disk Size, 1401 * Page 83 Data, 1402 * Logical Sector Size, 1403 * Physical Sector Size 1404 * 1405 * The first 64KB of the Metadata section is reserved for the metadata 1406 * header and entries; beyond that, the metadata items themselves reside. 1407 */ 1408 static int vhdx_create_new_metadata(BlockDriverState *bs, 1409 uint64_t image_size, 1410 uint32_t block_size, 1411 uint32_t sector_size, 1412 uint64_t metadata_offset, 1413 VHDXImageType type) 1414 { 1415 int ret = 0; 1416 uint32_t offset = 0; 1417 void *buffer = NULL; 1418 void *entry_buffer; 1419 VHDXMetadataTableHeader *md_table;; 1420 VHDXMetadataTableEntry *md_table_entry; 1421 1422 /* Metadata entries */ 1423 VHDXFileParameters *mt_file_params; 1424 VHDXVirtualDiskSize *mt_virtual_size; 1425 VHDXPage83Data *mt_page83; 1426 VHDXVirtualDiskLogicalSectorSize *mt_log_sector_size; 1427 VHDXVirtualDiskPhysicalSectorSize *mt_phys_sector_size; 1428 1429 entry_buffer = g_malloc0(sizeof(VHDXFileParameters) + 1430 sizeof(VHDXVirtualDiskSize) + 1431 sizeof(VHDXPage83Data) + 1432 sizeof(VHDXVirtualDiskLogicalSectorSize) + 1433 sizeof(VHDXVirtualDiskPhysicalSectorSize)); 1434 1435 mt_file_params = entry_buffer; 1436 offset += sizeof(VHDXFileParameters); 1437 mt_virtual_size = entry_buffer + offset; 1438 offset += sizeof(VHDXVirtualDiskSize); 1439 mt_page83 = entry_buffer + offset; 1440 offset += sizeof(VHDXPage83Data); 1441 mt_log_sector_size = entry_buffer + offset; 1442 offset += sizeof(VHDXVirtualDiskLogicalSectorSize); 1443 mt_phys_sector_size = entry_buffer + offset; 1444 1445 mt_file_params->block_size = cpu_to_le32(block_size); 1446 if (type == VHDX_TYPE_FIXED) { 1447 mt_file_params->data_bits |= VHDX_PARAMS_LEAVE_BLOCKS_ALLOCED; 1448 cpu_to_le32s(&mt_file_params->data_bits); 1449 } 1450 1451 vhdx_guid_generate(&mt_page83->page_83_data); 1452 cpu_to_leguids(&mt_page83->page_83_data); 1453 mt_virtual_size->virtual_disk_size = cpu_to_le64(image_size); 1454 mt_log_sector_size->logical_sector_size = cpu_to_le32(sector_size); 1455 mt_phys_sector_size->physical_sector_size = cpu_to_le32(sector_size); 1456 1457 buffer = g_malloc0(VHDX_HEADER_BLOCK_SIZE); 1458 md_table = buffer; 1459 1460 md_table->signature = VHDX_METADATA_SIGNATURE; 1461 md_table->entry_count = 5; 1462 vhdx_metadata_header_le_export(md_table); 1463 1464 1465 /* This will reference beyond the reserved table portion */ 1466 offset = 64 * KiB; 1467 1468 md_table_entry = buffer + sizeof(VHDXMetadataTableHeader); 1469 1470 md_table_entry[0].item_id = file_param_guid; 1471 md_table_entry[0].offset = offset; 1472 md_table_entry[0].length = sizeof(VHDXFileParameters); 1473 md_table_entry[0].data_bits |= VHDX_META_FLAGS_IS_REQUIRED; 1474 offset += md_table_entry[0].length; 1475 vhdx_metadata_entry_le_export(&md_table_entry[0]); 1476 1477 md_table_entry[1].item_id = virtual_size_guid; 1478 md_table_entry[1].offset = offset; 1479 md_table_entry[1].length = sizeof(VHDXVirtualDiskSize); 1480 md_table_entry[1].data_bits |= VHDX_META_FLAGS_IS_REQUIRED | 1481 VHDX_META_FLAGS_IS_VIRTUAL_DISK; 1482 offset += md_table_entry[1].length; 1483 vhdx_metadata_entry_le_export(&md_table_entry[1]); 1484 1485 md_table_entry[2].item_id = page83_guid; 1486 md_table_entry[2].offset = offset; 1487 md_table_entry[2].length = sizeof(VHDXPage83Data); 1488 md_table_entry[2].data_bits |= VHDX_META_FLAGS_IS_REQUIRED | 1489 VHDX_META_FLAGS_IS_VIRTUAL_DISK; 1490 offset += md_table_entry[2].length; 1491 vhdx_metadata_entry_le_export(&md_table_entry[2]); 1492 1493 md_table_entry[3].item_id = logical_sector_guid; 1494 md_table_entry[3].offset = offset; 1495 md_table_entry[3].length = sizeof(VHDXVirtualDiskLogicalSectorSize); 1496 md_table_entry[3].data_bits |= VHDX_META_FLAGS_IS_REQUIRED | 1497 VHDX_META_FLAGS_IS_VIRTUAL_DISK; 1498 offset += md_table_entry[3].length; 1499 vhdx_metadata_entry_le_export(&md_table_entry[3]); 1500 1501 md_table_entry[4].item_id = phys_sector_guid; 1502 md_table_entry[4].offset = offset; 1503 md_table_entry[4].length = sizeof(VHDXVirtualDiskPhysicalSectorSize); 1504 md_table_entry[4].data_bits |= VHDX_META_FLAGS_IS_REQUIRED | 1505 VHDX_META_FLAGS_IS_VIRTUAL_DISK; 1506 vhdx_metadata_entry_le_export(&md_table_entry[4]); 1507 1508 ret = bdrv_pwrite(bs, metadata_offset, buffer, VHDX_HEADER_BLOCK_SIZE); 1509 if (ret < 0) { 1510 goto exit; 1511 } 1512 1513 ret = bdrv_pwrite(bs, metadata_offset + (64 * KiB), entry_buffer, 1514 VHDX_HEADER_BLOCK_SIZE); 1515 if (ret < 0) { 1516 goto exit; 1517 } 1518 1519 1520 exit: 1521 g_free(buffer); 1522 g_free(entry_buffer); 1523 return ret; 1524 } 1525 1526 /* This create the actual BAT itself. We currently only support 1527 * 'Dynamic' and 'Fixed' image types. 1528 * 1529 * Dynamic images: default state of the BAT is all zeroes. 1530 * 1531 * Fixed images: default state of the BAT is fully populated, with 1532 * file offsets and state PAYLOAD_BLOCK_FULLY_PRESENT. 1533 */ 1534 static int vhdx_create_bat(BlockDriverState *bs, BDRVVHDXState *s, 1535 uint64_t image_size, VHDXImageType type, 1536 bool use_zero_blocks, VHDXRegionTableEntry *rt_bat) 1537 { 1538 int ret = 0; 1539 uint64_t data_file_offset; 1540 uint64_t total_sectors = 0; 1541 uint64_t sector_num = 0; 1542 uint64_t unused; 1543 int block_state; 1544 VHDXSectorInfo sinfo; 1545 1546 assert(s->bat == NULL); 1547 1548 /* this gives a data start after BAT/bitmap entries, and well 1549 * past any metadata entries (with a 4 MB buffer for future 1550 * expansion */ 1551 data_file_offset = rt_bat->file_offset + rt_bat->length + 5 * MiB; 1552 total_sectors = image_size >> s->logical_sector_size_bits; 1553 1554 if (type == VHDX_TYPE_DYNAMIC) { 1555 /* All zeroes, so we can just extend the file - the end of the BAT 1556 * is the furthest thing we have written yet */ 1557 ret = bdrv_truncate(bs, data_file_offset); 1558 if (ret < 0) { 1559 goto exit; 1560 } 1561 } else if (type == VHDX_TYPE_FIXED) { 1562 ret = bdrv_truncate(bs, data_file_offset + image_size); 1563 if (ret < 0) { 1564 goto exit; 1565 } 1566 } else { 1567 ret = -ENOTSUP; 1568 goto exit; 1569 } 1570 1571 if (type == VHDX_TYPE_FIXED || 1572 use_zero_blocks || 1573 bdrv_has_zero_init(bs) == 0) { 1574 /* for a fixed file, the default BAT entry is not zero */ 1575 s->bat = g_malloc0(rt_bat->length); 1576 block_state = type == VHDX_TYPE_FIXED ? PAYLOAD_BLOCK_FULLY_PRESENT : 1577 PAYLOAD_BLOCK_NOT_PRESENT; 1578 block_state = use_zero_blocks ? PAYLOAD_BLOCK_ZERO : block_state; 1579 /* fill the BAT by emulating sector writes of sectors_per_block size */ 1580 while (sector_num < total_sectors) { 1581 vhdx_block_translate(s, sector_num, s->sectors_per_block, &sinfo); 1582 sinfo.file_offset = data_file_offset + 1583 (sector_num << s->logical_sector_size_bits); 1584 sinfo.file_offset = ROUND_UP(sinfo.file_offset, MiB); 1585 vhdx_update_bat_table_entry(bs, s, &sinfo, &unused, &unused, 1586 block_state); 1587 cpu_to_le64s(&s->bat[sinfo.bat_idx]); 1588 sector_num += s->sectors_per_block; 1589 } 1590 ret = bdrv_pwrite(bs, rt_bat->file_offset, s->bat, rt_bat->length); 1591 if (ret < 0) { 1592 goto exit; 1593 } 1594 } 1595 1596 1597 1598 exit: 1599 g_free(s->bat); 1600 return ret; 1601 } 1602 1603 /* Creates the region table header, and region table entries. 1604 * There are 2 supported region table entries: BAT, and Metadata/ 1605 * 1606 * As the calculations for the BAT region table are also needed 1607 * to create the BAT itself, we will also cause the BAT to be 1608 * created. 1609 */ 1610 static int vhdx_create_new_region_table(BlockDriverState *bs, 1611 uint64_t image_size, 1612 uint32_t block_size, 1613 uint32_t sector_size, 1614 uint32_t log_size, 1615 bool use_zero_blocks, 1616 VHDXImageType type, 1617 uint64_t *metadata_offset) 1618 { 1619 int ret = 0; 1620 uint32_t offset = 0; 1621 void *buffer = NULL; 1622 BDRVVHDXState *s = NULL; 1623 VHDXRegionTableHeader *region_table; 1624 VHDXRegionTableEntry *rt_bat; 1625 VHDXRegionTableEntry *rt_metadata; 1626 1627 assert(metadata_offset != NULL); 1628 1629 /* Populate enough of the BDRVVHDXState to be able to use the 1630 * pre-existing BAT calculation, translation, and update functions */ 1631 s = g_malloc0(sizeof(BDRVVHDXState)); 1632 1633 s->chunk_ratio = (VHDX_MAX_SECTORS_PER_BLOCK) * 1634 (uint64_t) sector_size / (uint64_t) block_size; 1635 1636 s->sectors_per_block = block_size / sector_size; 1637 s->virtual_disk_size = image_size; 1638 s->block_size = block_size; 1639 s->logical_sector_size = sector_size; 1640 1641 vhdx_set_shift_bits(s); 1642 1643 vhdx_calc_bat_entries(s); 1644 1645 /* At this point the VHDX state is populated enough for creation */ 1646 1647 /* a single buffer is used so we can calculate the checksum over the 1648 * entire 64KB block */ 1649 buffer = g_malloc0(VHDX_HEADER_BLOCK_SIZE); 1650 region_table = buffer; 1651 offset += sizeof(VHDXRegionTableHeader); 1652 rt_bat = buffer + offset; 1653 offset += sizeof(VHDXRegionTableEntry); 1654 rt_metadata = buffer + offset; 1655 1656 region_table->signature = VHDX_REGION_SIGNATURE; 1657 region_table->entry_count = 2; /* BAT and Metadata */ 1658 1659 rt_bat->guid = bat_guid; 1660 rt_bat->length = ROUND_UP(s->bat_entries * sizeof(VHDXBatEntry), MiB); 1661 rt_bat->file_offset = ROUND_UP(VHDX_HEADER_SECTION_END + log_size, MiB); 1662 s->bat_offset = rt_bat->file_offset; 1663 1664 rt_metadata->guid = metadata_guid; 1665 rt_metadata->file_offset = ROUND_UP(rt_bat->file_offset + rt_bat->length, 1666 MiB); 1667 rt_metadata->length = 1 * MiB; /* min size, and more than enough */ 1668 *metadata_offset = rt_metadata->file_offset; 1669 1670 vhdx_update_checksum(buffer, VHDX_HEADER_BLOCK_SIZE, 1671 offsetof(VHDXRegionTableHeader, checksum)); 1672 1673 1674 /* The region table gives us the data we need to create the BAT, 1675 * so do that now */ 1676 ret = vhdx_create_bat(bs, s, image_size, type, use_zero_blocks, rt_bat); 1677 1678 /* Now write out the region headers to disk */ 1679 vhdx_region_header_le_export(region_table); 1680 vhdx_region_entry_le_export(rt_bat); 1681 vhdx_region_entry_le_export(rt_metadata); 1682 1683 ret = bdrv_pwrite(bs, VHDX_REGION_TABLE_OFFSET, buffer, 1684 VHDX_HEADER_BLOCK_SIZE); 1685 if (ret < 0) { 1686 goto exit; 1687 } 1688 1689 ret = bdrv_pwrite(bs, VHDX_REGION_TABLE2_OFFSET, buffer, 1690 VHDX_HEADER_BLOCK_SIZE); 1691 if (ret < 0) { 1692 goto exit; 1693 } 1694 1695 1696 exit: 1697 g_free(s); 1698 g_free(buffer); 1699 return ret; 1700 } 1701 1702 /* We need to create the following elements: 1703 * 1704 * .-----------------------------------------------------------------. 1705 * | (A) | (B) | (C) | (D) | (E) | 1706 * | File ID | Header1 | Header 2 | Region Tbl 1 | Region Tbl 2 | 1707 * | | | | | | 1708 * .-----------------------------------------------------------------. 1709 * 0 64KB 128KB 192KB 256KB 320KB 1710 * 1711 * 1712 * .---- ~ ----------- ~ ------------ ~ ---------------- ~ -----------. 1713 * | (F) | (G) | (H) | | 1714 * | Journal Log | BAT / Bitmap | Metadata | .... data ...... | 1715 * | | | | | 1716 * .---- ~ ----------- ~ ------------ ~ ---------------- ~ -----------. 1717 * 1MB 1718 */ 1719 static int vhdx_create(const char *filename, QEMUOptionParameter *options, 1720 Error **errp) 1721 { 1722 int ret = 0; 1723 uint64_t image_size = (uint64_t) 2 * GiB; 1724 uint32_t log_size = 1 * MiB; 1725 uint32_t block_size = 0; 1726 uint64_t signature; 1727 uint64_t metadata_offset; 1728 bool use_zero_blocks = false; 1729 1730 gunichar2 *creator = NULL; 1731 glong creator_items; 1732 BlockDriverState *bs; 1733 const char *type = NULL; 1734 VHDXImageType image_type; 1735 Error *local_err = NULL; 1736 1737 while (options && options->name) { 1738 if (!strcmp(options->name, BLOCK_OPT_SIZE)) { 1739 image_size = options->value.n; 1740 } else if (!strcmp(options->name, VHDX_BLOCK_OPT_LOG_SIZE)) { 1741 log_size = options->value.n; 1742 } else if (!strcmp(options->name, VHDX_BLOCK_OPT_BLOCK_SIZE)) { 1743 block_size = options->value.n; 1744 } else if (!strcmp(options->name, BLOCK_OPT_SUBFMT)) { 1745 type = options->value.s; 1746 } else if (!strcmp(options->name, VHDX_BLOCK_OPT_ZERO)) { 1747 use_zero_blocks = options->value.n != 0; 1748 } 1749 options++; 1750 } 1751 1752 if (image_size > VHDX_MAX_IMAGE_SIZE) { 1753 error_setg_errno(errp, EINVAL, "Image size too large; max of 64TB"); 1754 ret = -EINVAL; 1755 goto exit; 1756 } 1757 1758 if (type == NULL) { 1759 type = "dynamic"; 1760 } 1761 1762 if (!strcmp(type, "dynamic")) { 1763 image_type = VHDX_TYPE_DYNAMIC; 1764 } else if (!strcmp(type, "fixed")) { 1765 image_type = VHDX_TYPE_FIXED; 1766 } else if (!strcmp(type, "differencing")) { 1767 error_setg_errno(errp, ENOTSUP, 1768 "Differencing files not yet supported"); 1769 ret = -ENOTSUP; 1770 goto exit; 1771 } else { 1772 ret = -EINVAL; 1773 goto exit; 1774 } 1775 1776 /* These are pretty arbitrary, and mainly designed to keep the BAT 1777 * size reasonable to load into RAM */ 1778 if (block_size == 0) { 1779 if (image_size > 32 * TiB) { 1780 block_size = 64 * MiB; 1781 } else if (image_size > (uint64_t) 100 * GiB) { 1782 block_size = 32 * MiB; 1783 } else if (image_size > 1 * GiB) { 1784 block_size = 16 * MiB; 1785 } else { 1786 block_size = 8 * MiB; 1787 } 1788 } 1789 1790 1791 /* make the log size close to what was specified, but must be 1792 * min 1MB, and multiple of 1MB */ 1793 log_size = ROUND_UP(log_size, MiB); 1794 1795 block_size = ROUND_UP(block_size, MiB); 1796 block_size = block_size > VHDX_BLOCK_SIZE_MAX ? VHDX_BLOCK_SIZE_MAX : 1797 block_size; 1798 1799 ret = bdrv_create_file(filename, options, &local_err); 1800 if (ret < 0) { 1801 error_propagate(errp, local_err); 1802 goto exit; 1803 } 1804 1805 bs = NULL; 1806 ret = bdrv_open(&bs, filename, NULL, NULL, BDRV_O_RDWR | BDRV_O_PROTOCOL, 1807 NULL, &local_err); 1808 if (ret < 0) { 1809 error_propagate(errp, local_err); 1810 goto exit; 1811 } 1812 1813 /* Create (A) */ 1814 1815 /* The creator field is optional, but may be useful for 1816 * debugging / diagnostics */ 1817 creator = g_utf8_to_utf16("QEMU v" QEMU_VERSION, -1, NULL, 1818 &creator_items, NULL); 1819 signature = cpu_to_le64(VHDX_FILE_SIGNATURE); 1820 ret = bdrv_pwrite(bs, VHDX_FILE_ID_OFFSET, &signature, sizeof(signature)); 1821 if (ret < 0) { 1822 goto delete_and_exit; 1823 } 1824 if (creator) { 1825 ret = bdrv_pwrite(bs, VHDX_FILE_ID_OFFSET + sizeof(signature), 1826 creator, creator_items * sizeof(gunichar2)); 1827 if (ret < 0) { 1828 goto delete_and_exit; 1829 } 1830 } 1831 1832 1833 /* Creates (B),(C) */ 1834 ret = vhdx_create_new_headers(bs, image_size, log_size); 1835 if (ret < 0) { 1836 goto delete_and_exit; 1837 } 1838 1839 /* Creates (D),(E),(G) explicitly. (F) created as by-product */ 1840 ret = vhdx_create_new_region_table(bs, image_size, block_size, 512, 1841 log_size, use_zero_blocks, image_type, 1842 &metadata_offset); 1843 if (ret < 0) { 1844 goto delete_and_exit; 1845 } 1846 1847 /* Creates (H) */ 1848 ret = vhdx_create_new_metadata(bs, image_size, block_size, 512, 1849 metadata_offset, image_type); 1850 if (ret < 0) { 1851 goto delete_and_exit; 1852 } 1853 1854 1855 1856 delete_and_exit: 1857 bdrv_unref(bs); 1858 exit: 1859 g_free(creator); 1860 return ret; 1861 } 1862 1863 /* If opened r/w, the VHDX driver will automatically replay the log, 1864 * if one is present, inside the vhdx_open() call. 1865 * 1866 * If qemu-img check -r all is called, the image is automatically opened 1867 * r/w and any log has already been replayed, so there is nothing (currently) 1868 * for us to do here 1869 */ 1870 static int vhdx_check(BlockDriverState *bs, BdrvCheckResult *result, 1871 BdrvCheckMode fix) 1872 { 1873 BDRVVHDXState *s = bs->opaque; 1874 1875 if (s->log_replayed_on_open) { 1876 result->corruptions_fixed++; 1877 } 1878 return 0; 1879 } 1880 1881 static QEMUOptionParameter vhdx_create_options[] = { 1882 { 1883 .name = BLOCK_OPT_SIZE, 1884 .type = OPT_SIZE, 1885 .help = "Virtual disk size; max of 64TB." 1886 }, 1887 { 1888 .name = VHDX_BLOCK_OPT_LOG_SIZE, 1889 .type = OPT_SIZE, 1890 .value.n = 1 * MiB, 1891 .help = "Log size; min 1MB." 1892 }, 1893 { 1894 .name = VHDX_BLOCK_OPT_BLOCK_SIZE, 1895 .type = OPT_SIZE, 1896 .value.n = 0, 1897 .help = "Block Size; min 1MB, max 256MB. " \ 1898 "0 means auto-calculate based on image size." 1899 }, 1900 { 1901 .name = BLOCK_OPT_SUBFMT, 1902 .type = OPT_STRING, 1903 .help = "VHDX format type, can be either 'dynamic' or 'fixed'. "\ 1904 "Default is 'dynamic'." 1905 }, 1906 { 1907 .name = VHDX_BLOCK_OPT_ZERO, 1908 .type = OPT_FLAG, 1909 .help = "Force use of payload blocks of type 'ZERO'. Non-standard." 1910 }, 1911 { NULL } 1912 }; 1913 1914 static BlockDriver bdrv_vhdx = { 1915 .format_name = "vhdx", 1916 .instance_size = sizeof(BDRVVHDXState), 1917 .bdrv_probe = vhdx_probe, 1918 .bdrv_open = vhdx_open, 1919 .bdrv_close = vhdx_close, 1920 .bdrv_reopen_prepare = vhdx_reopen_prepare, 1921 .bdrv_co_readv = vhdx_co_readv, 1922 .bdrv_co_writev = vhdx_co_writev, 1923 .bdrv_create = vhdx_create, 1924 .bdrv_get_info = vhdx_get_info, 1925 .bdrv_check = vhdx_check, 1926 1927 .create_options = vhdx_create_options, 1928 }; 1929 1930 static void bdrv_vhdx_init(void) 1931 { 1932 bdrv_register(&bdrv_vhdx); 1933 } 1934 1935 block_init(bdrv_vhdx_init); 1936