| /* |
| * Block driver for Hyper-V VHDX Images |
| * |
| * Copyright (c) 2013 Red Hat, Inc., |
| * |
| * Authors: |
| * Jeff Cody <jcody@redhat.com> |
| * |
| * This is based on the "VHDX Format Specification v1.00", published 8/25/2012 |
| * by Microsoft: |
| * https://www.microsoft.com/en-us/download/details.aspx?id=34750 |
| * |
| * This work is licensed under the terms of the GNU LGPL, version 2 or later. |
| * See the COPYING.LIB file in the top-level directory. |
| * |
| */ |
| |
| #include "qemu-common.h" |
| #include "block/block_int.h" |
| #include "qemu/module.h" |
| #include "qemu/crc32c.h" |
| #include "block/vhdx.h" |
| #include "migration/migration.h" |
| |
| #include <uuid/uuid.h> |
| #include <glib.h> |
| |
| /* Options for VHDX creation */ |
| |
| #define VHDX_BLOCK_OPT_LOG_SIZE "log_size" |
| #define VHDX_BLOCK_OPT_BLOCK_SIZE "block_size" |
| #define VHDX_BLOCK_OPT_ZERO "block_state_zero" |
| |
| typedef enum VHDXImageType { |
| VHDX_TYPE_DYNAMIC = 0, |
| VHDX_TYPE_FIXED, |
| VHDX_TYPE_DIFFERENCING, /* Currently unsupported */ |
| } VHDXImageType; |
| |
| /* Several metadata and region table data entries are identified by |
| * guids in a MS-specific GUID format. */ |
| |
| |
| /* ------- Known Region Table GUIDs ---------------------- */ |
| static const MSGUID bat_guid = { .data1 = 0x2dc27766, |
| .data2 = 0xf623, |
| .data3 = 0x4200, |
| .data4 = { 0x9d, 0x64, 0x11, 0x5e, |
| 0x9b, 0xfd, 0x4a, 0x08} }; |
| |
| static const MSGUID metadata_guid = { .data1 = 0x8b7ca206, |
| .data2 = 0x4790, |
| .data3 = 0x4b9a, |
| .data4 = { 0xb8, 0xfe, 0x57, 0x5f, |
| 0x05, 0x0f, 0x88, 0x6e} }; |
| |
| |
| |
| /* ------- Known Metadata Entry GUIDs ---------------------- */ |
| static const MSGUID file_param_guid = { .data1 = 0xcaa16737, |
| .data2 = 0xfa36, |
| .data3 = 0x4d43, |
| .data4 = { 0xb3, 0xb6, 0x33, 0xf0, |
| 0xaa, 0x44, 0xe7, 0x6b} }; |
| |
| static const MSGUID virtual_size_guid = { .data1 = 0x2FA54224, |
| .data2 = 0xcd1b, |
| .data3 = 0x4876, |
| .data4 = { 0xb2, 0x11, 0x5d, 0xbe, |
| 0xd8, 0x3b, 0xf4, 0xb8} }; |
| |
| static const MSGUID page83_guid = { .data1 = 0xbeca12ab, |
| .data2 = 0xb2e6, |
| .data3 = 0x4523, |
| .data4 = { 0x93, 0xef, 0xc3, 0x09, |
| 0xe0, 0x00, 0xc7, 0x46} }; |
| |
| |
| static const MSGUID phys_sector_guid = { .data1 = 0xcda348c7, |
| .data2 = 0x445d, |
| .data3 = 0x4471, |
| .data4 = { 0x9c, 0xc9, 0xe9, 0x88, |
| 0x52, 0x51, 0xc5, 0x56} }; |
| |
| static const MSGUID parent_locator_guid = { .data1 = 0xa8d35f2d, |
| .data2 = 0xb30b, |
| .data3 = 0x454d, |
| .data4 = { 0xab, 0xf7, 0xd3, |
| 0xd8, 0x48, 0x34, |
| 0xab, 0x0c} }; |
| |
| static const MSGUID logical_sector_guid = { .data1 = 0x8141bf1d, |
| .data2 = 0xa96f, |
| .data3 = 0x4709, |
| .data4 = { 0xba, 0x47, 0xf2, |
| 0x33, 0xa8, 0xfa, |
| 0xab, 0x5f} }; |
| |
| /* Each parent type must have a valid GUID; this is for parent images |
| * of type 'VHDX'. If we were to allow e.g. a QCOW2 parent, we would |
| * need to make up our own QCOW2 GUID type */ |
| static const MSGUID parent_vhdx_guid = { .data1 = 0xb04aefb7, |
| .data2 = 0xd19e, |
| .data3 = 0x4a81, |
| .data4 = { 0xb7, 0x89, 0x25, 0xb8, |
| 0xe9, 0x44, 0x59, 0x13} }; |
| |
| |
| #define META_FILE_PARAMETER_PRESENT 0x01 |
| #define META_VIRTUAL_DISK_SIZE_PRESENT 0x02 |
| #define META_PAGE_83_PRESENT 0x04 |
| #define META_LOGICAL_SECTOR_SIZE_PRESENT 0x08 |
| #define META_PHYS_SECTOR_SIZE_PRESENT 0x10 |
| #define META_PARENT_LOCATOR_PRESENT 0x20 |
| |
| #define META_ALL_PRESENT \ |
| (META_FILE_PARAMETER_PRESENT | META_VIRTUAL_DISK_SIZE_PRESENT | \ |
| META_PAGE_83_PRESENT | META_LOGICAL_SECTOR_SIZE_PRESENT | \ |
| META_PHYS_SECTOR_SIZE_PRESENT) |
| |
| |
| typedef struct VHDXSectorInfo { |
| uint32_t bat_idx; /* BAT entry index */ |
| uint32_t sectors_avail; /* sectors available in payload block */ |
| uint32_t bytes_left; /* bytes left in the block after data to r/w */ |
| uint32_t bytes_avail; /* bytes available in payload block */ |
| uint64_t file_offset; /* absolute offset in bytes, in file */ |
| uint64_t block_offset; /* block offset, in bytes */ |
| } VHDXSectorInfo; |
| |
| /* Calculates new checksum. |
| * |
| * Zero is substituted during crc calculation for the original crc field |
| * crc_offset: byte offset in buf of the buffer crc |
| * buf: buffer pointer |
| * size: size of buffer (must be > crc_offset+4) |
| * |
| * Note: The resulting checksum is in the CPU endianness, not necessarily |
| * in the file format endianness (LE). Any header export to disk should |
| * make sure that vhdx_header_le_export() is used to convert to the |
| * correct endianness |
| */ |
| uint32_t vhdx_update_checksum(uint8_t *buf, size_t size, int crc_offset) |
| { |
| uint32_t crc; |
| |
| assert(buf != NULL); |
| assert(size > (crc_offset + sizeof(crc))); |
| |
| memset(buf + crc_offset, 0, sizeof(crc)); |
| crc = crc32c(0xffffffff, buf, size); |
| memcpy(buf + crc_offset, &crc, sizeof(crc)); |
| |
| return crc; |
| } |
| |
| uint32_t vhdx_checksum_calc(uint32_t crc, uint8_t *buf, size_t size, |
| int crc_offset) |
| { |
| uint32_t crc_new; |
| uint32_t crc_orig; |
| assert(buf != NULL); |
| |
| if (crc_offset > 0) { |
| memcpy(&crc_orig, buf + crc_offset, sizeof(crc_orig)); |
| memset(buf + crc_offset, 0, sizeof(crc_orig)); |
| } |
| |
| crc_new = crc32c(crc, buf, size); |
| if (crc_offset > 0) { |
| memcpy(buf + crc_offset, &crc_orig, sizeof(crc_orig)); |
| } |
| |
| return crc_new; |
| } |
| |
| /* Validates the checksum of the buffer, with an in-place CRC. |
| * |
| * Zero is substituted during crc calculation for the original crc field, |
| * and the crc field is restored afterwards. But the buffer will be modifed |
| * during the calculation, so this may not be not suitable for multi-threaded |
| * use. |
| * |
| * crc_offset: byte offset in buf of the buffer crc |
| * buf: buffer pointer |
| * size: size of buffer (must be > crc_offset+4) |
| * |
| * returns true if checksum is valid, false otherwise |
| */ |
| bool vhdx_checksum_is_valid(uint8_t *buf, size_t size, int crc_offset) |
| { |
| uint32_t crc_orig; |
| uint32_t crc; |
| |
| assert(buf != NULL); |
| assert(size > (crc_offset + 4)); |
| |
| memcpy(&crc_orig, buf + crc_offset, sizeof(crc_orig)); |
| crc_orig = le32_to_cpu(crc_orig); |
| |
| crc = vhdx_checksum_calc(0xffffffff, buf, size, crc_offset); |
| |
| return crc == crc_orig; |
| } |
| |
| |
| /* |
| * This generates a UUID that is compliant with the MS GUIDs used |
| * in the VHDX spec (and elsewhere). |
| */ |
| void vhdx_guid_generate(MSGUID *guid) |
| { |
| uuid_t uuid; |
| assert(guid != NULL); |
| |
| uuid_generate(uuid); |
| memcpy(guid, uuid, sizeof(MSGUID)); |
| } |
| |
| /* Check for region overlaps inside the VHDX image */ |
| static int vhdx_region_check(BDRVVHDXState *s, uint64_t start, uint64_t length) |
| { |
| int ret = 0; |
| uint64_t end; |
| VHDXRegionEntry *r; |
| |
| end = start + length; |
| QLIST_FOREACH(r, &s->regions, entries) { |
| if (!((start >= r->end) || (end <= r->start))) { |
| ret = -EINVAL; |
| goto exit; |
| } |
| } |
| |
| exit: |
| return ret; |
| } |
| |
| /* Register a region for future checks */ |
| static void vhdx_region_register(BDRVVHDXState *s, |
| uint64_t start, uint64_t length) |
| { |
| VHDXRegionEntry *r; |
| |
| r = g_malloc0(sizeof(*r)); |
| |
| r->start = start; |
| r->end = start + length; |
| |
| QLIST_INSERT_HEAD(&s->regions, r, entries); |
| } |
| |
| /* Free all registered regions */ |
| static void vhdx_region_unregister_all(BDRVVHDXState *s) |
| { |
| VHDXRegionEntry *r, *r_next; |
| |
| QLIST_FOREACH_SAFE(r, &s->regions, entries, r_next) { |
| QLIST_REMOVE(r, entries); |
| g_free(r); |
| } |
| } |
| |
| static void vhdx_set_shift_bits(BDRVVHDXState *s) |
| { |
| s->logical_sector_size_bits = 31 - clz32(s->logical_sector_size); |
| s->sectors_per_block_bits = 31 - clz32(s->sectors_per_block); |
| s->chunk_ratio_bits = 63 - clz64(s->chunk_ratio); |
| s->block_size_bits = 31 - clz32(s->block_size); |
| } |
| |
| /* |
| * Per the MS VHDX Specification, for every VHDX file: |
| * - The header section is fixed size - 1 MB |
| * - The header section is always the first "object" |
| * - The first 64KB of the header is the File Identifier |
| * - The first uint64 (8 bytes) is the VHDX Signature ("vhdxfile") |
| * - The following 512 bytes constitute a UTF-16 string identifiying the |
| * software that created the file, and is optional and diagnostic only. |
| * |
| * Therefore, we probe by looking for the vhdxfile signature "vhdxfile" |
| */ |
| static int vhdx_probe(const uint8_t *buf, int buf_size, const char *filename) |
| { |
| if (buf_size >= 8 && !memcmp(buf, "vhdxfile", 8)) { |
| return 100; |
| } |
| return 0; |
| } |
| |
| /* |
| * Writes the header to the specified offset. |
| * |
| * This will optionally read in buffer data from disk (otherwise zero-fill), |
| * and then update the header checksum. Header is converted to proper |
| * endianness before being written to the specified file offset |
| */ |
| static int vhdx_write_header(BlockDriverState *bs_file, VHDXHeader *hdr, |
| uint64_t offset, bool read) |
| { |
| uint8_t *buffer = NULL; |
| int ret; |
| VHDXHeader header_le; |
| |
| assert(bs_file != NULL); |
| assert(hdr != NULL); |
| |
| /* the header checksum is not over just the packed size of VHDXHeader, |
| * but rather over the entire 'reserved' range for the header, which is |
| * 4KB (VHDX_HEADER_SIZE). */ |
| |
| buffer = qemu_blockalign(bs_file, VHDX_HEADER_SIZE); |
| if (read) { |
| /* if true, we can't assume the extra reserved bytes are 0 */ |
| ret = bdrv_pread(bs_file, offset, buffer, VHDX_HEADER_SIZE); |
| if (ret < 0) { |
| goto exit; |
| } |
| } else { |
| memset(buffer, 0, VHDX_HEADER_SIZE); |
| } |
| |
| /* overwrite the actual VHDXHeader portion */ |
| memcpy(buffer, hdr, sizeof(VHDXHeader)); |
| hdr->checksum = vhdx_update_checksum(buffer, VHDX_HEADER_SIZE, |
| offsetof(VHDXHeader, checksum)); |
| vhdx_header_le_export(hdr, &header_le); |
| ret = bdrv_pwrite_sync(bs_file, offset, &header_le, sizeof(VHDXHeader)); |
| |
| exit: |
| qemu_vfree(buffer); |
| return ret; |
| } |
| |
| /* Update the VHDX headers |
| * |
| * This follows the VHDX spec procedures for header updates. |
| * |
| * - non-current header is updated with largest sequence number |
| */ |
| static int vhdx_update_header(BlockDriverState *bs, BDRVVHDXState *s, |
| bool generate_data_write_guid, MSGUID *log_guid) |
| { |
| int ret = 0; |
| int hdr_idx = 0; |
| uint64_t header_offset = VHDX_HEADER1_OFFSET; |
| |
| VHDXHeader *active_header; |
| VHDXHeader *inactive_header; |
| |
| /* operate on the non-current header */ |
| if (s->curr_header == 0) { |
| hdr_idx = 1; |
| header_offset = VHDX_HEADER2_OFFSET; |
| } |
| |
| active_header = s->headers[s->curr_header]; |
| inactive_header = s->headers[hdr_idx]; |
| |
| inactive_header->sequence_number = active_header->sequence_number + 1; |
| |
| /* a new file guid must be generated before any file write, including |
| * headers */ |
| inactive_header->file_write_guid = s->session_guid; |
| |
| /* a new data guid only needs to be generated before any guest-visible |
| * writes (i.e. something observable via virtual disk read) */ |
| if (generate_data_write_guid) { |
| vhdx_guid_generate(&inactive_header->data_write_guid); |
| } |
| |
| /* update the log guid if present */ |
| if (log_guid) { |
| inactive_header->log_guid = *log_guid; |
| } |
| |
| vhdx_write_header(bs->file, inactive_header, header_offset, true); |
| if (ret < 0) { |
| goto exit; |
| } |
| s->curr_header = hdr_idx; |
| |
| exit: |
| return ret; |
| } |
| |
| /* |
| * The VHDX spec calls for header updates to be performed twice, so that both |
| * the current and non-current header have valid info |
| */ |
| int vhdx_update_headers(BlockDriverState *bs, BDRVVHDXState *s, |
| bool generate_data_write_guid, MSGUID *log_guid) |
| { |
| int ret; |
| |
| ret = vhdx_update_header(bs, s, generate_data_write_guid, log_guid); |
| if (ret < 0) { |
| return ret; |
| } |
| ret = vhdx_update_header(bs, s, generate_data_write_guid, log_guid); |
| return ret; |
| } |
| |
| /* opens the specified header block from the VHDX file header section */ |
| static int vhdx_parse_header(BlockDriverState *bs, BDRVVHDXState *s) |
| { |
| int ret = 0; |
| VHDXHeader *header1; |
| VHDXHeader *header2; |
| bool h1_valid = false; |
| bool h2_valid = false; |
| uint64_t h1_seq = 0; |
| uint64_t h2_seq = 0; |
| uint8_t *buffer; |
| |
| /* header1 & header2 are freed in vhdx_close() */ |
| header1 = qemu_blockalign(bs, sizeof(VHDXHeader)); |
| header2 = qemu_blockalign(bs, sizeof(VHDXHeader)); |
| |
| buffer = qemu_blockalign(bs, VHDX_HEADER_SIZE); |
| |
| s->headers[0] = header1; |
| s->headers[1] = header2; |
| |
| /* We have to read the whole VHDX_HEADER_SIZE instead of |
| * sizeof(VHDXHeader), because the checksum is over the whole |
| * region */ |
| ret = bdrv_pread(bs->file, VHDX_HEADER1_OFFSET, buffer, VHDX_HEADER_SIZE); |
| if (ret < 0) { |
| goto fail; |
| } |
| /* copy over just the relevant portion that we need */ |
| memcpy(header1, buffer, sizeof(VHDXHeader)); |
| vhdx_header_le_import(header1); |
| |
| if (vhdx_checksum_is_valid(buffer, VHDX_HEADER_SIZE, 4) && |
| !memcmp(&header1->signature, "head", 4) && |
| header1->version == 1) { |
| h1_seq = header1->sequence_number; |
| h1_valid = true; |
| } |
| |
| ret = bdrv_pread(bs->file, VHDX_HEADER2_OFFSET, buffer, VHDX_HEADER_SIZE); |
| if (ret < 0) { |
| goto fail; |
| } |
| /* copy over just the relevant portion that we need */ |
| memcpy(header2, buffer, sizeof(VHDXHeader)); |
| vhdx_header_le_import(header2); |
| |
| if (vhdx_checksum_is_valid(buffer, VHDX_HEADER_SIZE, 4) && |
| !memcmp(&header2->signature, "head", 4) && |
| header2->version == 1) { |
| h2_seq = header2->sequence_number; |
| h2_valid = true; |
| } |
| |
| /* If there is only 1 valid header (or no valid headers), we |
| * don't care what the sequence numbers are */ |
| if (h1_valid && !h2_valid) { |
| s->curr_header = 0; |
| } else if (!h1_valid && h2_valid) { |
| s->curr_header = 1; |
| } else if (!h1_valid && !h2_valid) { |
| ret = -EINVAL; |
| goto fail; |
| } else { |
| /* If both headers are valid, then we choose the active one by the |
| * highest sequence number. If the sequence numbers are equal, that is |
| * invalid */ |
| if (h1_seq > h2_seq) { |
| s->curr_header = 0; |
| } else if (h2_seq > h1_seq) { |
| s->curr_header = 1; |
| } else { |
| ret = -EINVAL; |
| goto fail; |
| } |
| } |
| |
| vhdx_region_register(s, s->headers[s->curr_header]->log_offset, |
| s->headers[s->curr_header]->log_length); |
| |
| ret = 0; |
| |
| goto exit; |
| |
| fail: |
| qerror_report(ERROR_CLASS_GENERIC_ERROR, "No valid VHDX header found"); |
| qemu_vfree(header1); |
| qemu_vfree(header2); |
| s->headers[0] = NULL; |
| s->headers[1] = NULL; |
| exit: |
| qemu_vfree(buffer); |
| return ret; |
| } |
| |
| |
| static int vhdx_open_region_tables(BlockDriverState *bs, BDRVVHDXState *s) |
| { |
| int ret = 0; |
| uint8_t *buffer; |
| int offset = 0; |
| VHDXRegionTableEntry rt_entry; |
| uint32_t i; |
| bool bat_rt_found = false; |
| bool metadata_rt_found = false; |
| |
| /* We have to read the whole 64KB block, because the crc32 is over the |
| * whole block */ |
| buffer = qemu_blockalign(bs, VHDX_HEADER_BLOCK_SIZE); |
| |
| ret = bdrv_pread(bs->file, VHDX_REGION_TABLE_OFFSET, buffer, |
| VHDX_HEADER_BLOCK_SIZE); |
| if (ret < 0) { |
| goto fail; |
| } |
| memcpy(&s->rt, buffer, sizeof(s->rt)); |
| vhdx_region_header_le_import(&s->rt); |
| offset += sizeof(s->rt); |
| |
| if (!vhdx_checksum_is_valid(buffer, VHDX_HEADER_BLOCK_SIZE, 4) || |
| memcmp(&s->rt.signature, "regi", 4)) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| /* Per spec, maximum region table entry count is 2047 */ |
| if (s->rt.entry_count > 2047) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| for (i = 0; i < s->rt.entry_count; i++) { |
| memcpy(&rt_entry, buffer + offset, sizeof(rt_entry)); |
| offset += sizeof(rt_entry); |
| |
| vhdx_region_entry_le_import(&rt_entry); |
| |
| /* check for region overlap between these entries, and any |
| * other memory regions in the file */ |
| ret = vhdx_region_check(s, rt_entry.file_offset, rt_entry.length); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| vhdx_region_register(s, rt_entry.file_offset, rt_entry.length); |
| |
| /* see if we recognize the entry */ |
| if (guid_eq(rt_entry.guid, bat_guid)) { |
| /* must be unique; if we have already found it this is invalid */ |
| if (bat_rt_found) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| bat_rt_found = true; |
| s->bat_rt = rt_entry; |
| continue; |
| } |
| |
| if (guid_eq(rt_entry.guid, metadata_guid)) { |
| /* must be unique; if we have already found it this is invalid */ |
| if (metadata_rt_found) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| metadata_rt_found = true; |
| s->metadata_rt = rt_entry; |
| continue; |
| } |
| |
| if (rt_entry.data_bits & VHDX_REGION_ENTRY_REQUIRED) { |
| /* cannot read vhdx file - required region table entry that |
| * we do not understand. per spec, we must fail to open */ |
| ret = -ENOTSUP; |
| goto fail; |
| } |
| } |
| |
| if (!bat_rt_found || !metadata_rt_found) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| ret = 0; |
| |
| fail: |
| qemu_vfree(buffer); |
| return ret; |
| } |
| |
| |
| |
| /* Metadata initial parser |
| * |
| * This loads all the metadata entry fields. This may cause additional |
| * fields to be processed (e.g. parent locator, etc..). |
| * |
| * There are 5 Metadata items that are always required: |
| * - File Parameters (block size, has a parent) |
| * - Virtual Disk Size (size, in bytes, of the virtual drive) |
| * - Page 83 Data (scsi page 83 guid) |
| * - Logical Sector Size (logical sector size in bytes, either 512 or |
| * 4096. We only support 512 currently) |
| * - Physical Sector Size (512 or 4096) |
| * |
| * Also, if the File Parameters indicate this is a differencing file, |
| * we must also look for the Parent Locator metadata item. |
| */ |
| static int vhdx_parse_metadata(BlockDriverState *bs, BDRVVHDXState *s) |
| { |
| int ret = 0; |
| uint8_t *buffer; |
| int offset = 0; |
| uint32_t i = 0; |
| VHDXMetadataTableEntry md_entry; |
| |
| buffer = qemu_blockalign(bs, VHDX_METADATA_TABLE_MAX_SIZE); |
| |
| ret = bdrv_pread(bs->file, s->metadata_rt.file_offset, buffer, |
| VHDX_METADATA_TABLE_MAX_SIZE); |
| if (ret < 0) { |
| goto exit; |
| } |
| memcpy(&s->metadata_hdr, buffer, sizeof(s->metadata_hdr)); |
| offset += sizeof(s->metadata_hdr); |
| |
| vhdx_metadata_header_le_import(&s->metadata_hdr); |
| |
| if (memcmp(&s->metadata_hdr.signature, "metadata", 8)) { |
| ret = -EINVAL; |
| goto exit; |
| } |
| |
| s->metadata_entries.present = 0; |
| |
| if ((s->metadata_hdr.entry_count * sizeof(md_entry)) > |
| (VHDX_METADATA_TABLE_MAX_SIZE - offset)) { |
| ret = -EINVAL; |
| goto exit; |
| } |
| |
| for (i = 0; i < s->metadata_hdr.entry_count; i++) { |
| memcpy(&md_entry, buffer + offset, sizeof(md_entry)); |
| offset += sizeof(md_entry); |
| |
| vhdx_metadata_entry_le_import(&md_entry); |
| |
| if (guid_eq(md_entry.item_id, file_param_guid)) { |
| if (s->metadata_entries.present & META_FILE_PARAMETER_PRESENT) { |
| ret = -EINVAL; |
| goto exit; |
| } |
| s->metadata_entries.file_parameters_entry = md_entry; |
| s->metadata_entries.present |= META_FILE_PARAMETER_PRESENT; |
| continue; |
| } |
| |
| if (guid_eq(md_entry.item_id, virtual_size_guid)) { |
| if (s->metadata_entries.present & META_VIRTUAL_DISK_SIZE_PRESENT) { |
| ret = -EINVAL; |
| goto exit; |
| } |
| s->metadata_entries.virtual_disk_size_entry = md_entry; |
| s->metadata_entries.present |= META_VIRTUAL_DISK_SIZE_PRESENT; |
| continue; |
| } |
| |
| if (guid_eq(md_entry.item_id, page83_guid)) { |
| if (s->metadata_entries.present & META_PAGE_83_PRESENT) { |
| ret = -EINVAL; |
| goto exit; |
| } |
| s->metadata_entries.page83_data_entry = md_entry; |
| s->metadata_entries.present |= META_PAGE_83_PRESENT; |
| continue; |
| } |
| |
| if (guid_eq(md_entry.item_id, logical_sector_guid)) { |
| if (s->metadata_entries.present & |
| META_LOGICAL_SECTOR_SIZE_PRESENT) { |
| ret = -EINVAL; |
| goto exit; |
| } |
| s->metadata_entries.logical_sector_size_entry = md_entry; |
| s->metadata_entries.present |= META_LOGICAL_SECTOR_SIZE_PRESENT; |
| continue; |
| } |
| |
| if (guid_eq(md_entry.item_id, phys_sector_guid)) { |
| if (s->metadata_entries.present & META_PHYS_SECTOR_SIZE_PRESENT) { |
| ret = -EINVAL; |
| goto exit; |
| } |
| s->metadata_entries.phys_sector_size_entry = md_entry; |
| s->metadata_entries.present |= META_PHYS_SECTOR_SIZE_PRESENT; |
| continue; |
| } |
| |
| if (guid_eq(md_entry.item_id, parent_locator_guid)) { |
| if (s->metadata_entries.present & META_PARENT_LOCATOR_PRESENT) { |
| ret = -EINVAL; |
| goto exit; |
| } |
| s->metadata_entries.parent_locator_entry = md_entry; |
| s->metadata_entries.present |= META_PARENT_LOCATOR_PRESENT; |
| continue; |
| } |
| |
| if (md_entry.data_bits & VHDX_META_FLAGS_IS_REQUIRED) { |
| /* cannot read vhdx file - required region table entry that |
| * we do not understand. per spec, we must fail to open */ |
| ret = -ENOTSUP; |
| goto exit; |
| } |
| } |
| |
| if (s->metadata_entries.present != META_ALL_PRESENT) { |
| ret = -ENOTSUP; |
| goto exit; |
| } |
| |
| ret = bdrv_pread(bs->file, |
| s->metadata_entries.file_parameters_entry.offset |
| + s->metadata_rt.file_offset, |
| &s->params, |
| sizeof(s->params)); |
| |
| if (ret < 0) { |
| goto exit; |
| } |
| |
| le32_to_cpus(&s->params.block_size); |
| le32_to_cpus(&s->params.data_bits); |
| |
| |
| /* We now have the file parameters, so we can tell if this is a |
| * differencing file (i.e.. has_parent), is dynamic or fixed |
| * sized (leave_blocks_allocated), and the block size */ |
| |
| /* The parent locator required iff the file parameters has_parent set */ |
| if (s->params.data_bits & VHDX_PARAMS_HAS_PARENT) { |
| if (s->metadata_entries.present & META_PARENT_LOCATOR_PRESENT) { |
| /* TODO: parse parent locator fields */ |
| ret = -ENOTSUP; /* temp, until differencing files are supported */ |
| goto exit; |
| } else { |
| /* if has_parent is set, but there is not parent locator present, |
| * then that is an invalid combination */ |
| ret = -EINVAL; |
| goto exit; |
| } |
| } |
| |
| /* determine virtual disk size, logical sector size, |
| * and phys sector size */ |
| |
| ret = bdrv_pread(bs->file, |
| s->metadata_entries.virtual_disk_size_entry.offset |
| + s->metadata_rt.file_offset, |
| &s->virtual_disk_size, |
| sizeof(uint64_t)); |
| if (ret < 0) { |
| goto exit; |
| } |
| ret = bdrv_pread(bs->file, |
| s->metadata_entries.logical_sector_size_entry.offset |
| + s->metadata_rt.file_offset, |
| &s->logical_sector_size, |
| sizeof(uint32_t)); |
| if (ret < 0) { |
| goto exit; |
| } |
| ret = bdrv_pread(bs->file, |
| s->metadata_entries.phys_sector_size_entry.offset |
| + s->metadata_rt.file_offset, |
| &s->physical_sector_size, |
| sizeof(uint32_t)); |
| if (ret < 0) { |
| goto exit; |
| } |
| |
| le64_to_cpus(&s->virtual_disk_size); |
| le32_to_cpus(&s->logical_sector_size); |
| le32_to_cpus(&s->physical_sector_size); |
| |
| if (s->logical_sector_size == 0 || s->params.block_size == 0) { |
| ret = -EINVAL; |
| goto exit; |
| } |
| |
| /* both block_size and sector_size are guaranteed powers of 2 */ |
| s->sectors_per_block = s->params.block_size / s->logical_sector_size; |
| s->chunk_ratio = (VHDX_MAX_SECTORS_PER_BLOCK) * |
| (uint64_t)s->logical_sector_size / |
| (uint64_t)s->params.block_size; |
| |
| /* These values are ones we will want to use for division / multiplication |
| * later on, and they are all guaranteed (per the spec) to be powers of 2, |
| * so we can take advantage of that for shift operations during |
| * reads/writes */ |
| if (s->logical_sector_size & (s->logical_sector_size - 1)) { |
| ret = -EINVAL; |
| goto exit; |
| } |
| if (s->sectors_per_block & (s->sectors_per_block - 1)) { |
| ret = -EINVAL; |
| goto exit; |
| } |
| if (s->chunk_ratio & (s->chunk_ratio - 1)) { |
| ret = -EINVAL; |
| goto exit; |
| } |
| s->block_size = s->params.block_size; |
| if (s->block_size & (s->block_size - 1)) { |
| ret = -EINVAL; |
| goto exit; |
| } |
| |
| vhdx_set_shift_bits(s); |
| |
| ret = 0; |
| |
| exit: |
| qemu_vfree(buffer); |
| return ret; |
| } |
| |
| /* |
| * Calculate the number of BAT entries, including sector |
| * bitmap entries. |
| */ |
| static void vhdx_calc_bat_entries(BDRVVHDXState *s) |
| { |
| uint32_t data_blocks_cnt, bitmap_blocks_cnt; |
| |
| data_blocks_cnt = s->virtual_disk_size >> s->block_size_bits; |
| if (s->virtual_disk_size - (data_blocks_cnt << s->block_size_bits)) { |
| data_blocks_cnt++; |
| } |
| bitmap_blocks_cnt = data_blocks_cnt >> s->chunk_ratio_bits; |
| if (data_blocks_cnt - (bitmap_blocks_cnt << s->chunk_ratio_bits)) { |
| bitmap_blocks_cnt++; |
| } |
| |
| if (s->parent_entries) { |
| s->bat_entries = bitmap_blocks_cnt * (s->chunk_ratio + 1); |
| } else { |
| s->bat_entries = data_blocks_cnt + |
| ((data_blocks_cnt - 1) >> s->chunk_ratio_bits); |
| } |
| |
| } |
| |
| static void vhdx_close(BlockDriverState *bs) |
| { |
| BDRVVHDXState *s = bs->opaque; |
| qemu_vfree(s->headers[0]); |
| s->headers[0] = NULL; |
| qemu_vfree(s->headers[1]); |
| s->headers[1] = NULL; |
| qemu_vfree(s->bat); |
| s->bat = NULL; |
| qemu_vfree(s->parent_entries); |
| s->parent_entries = NULL; |
| migrate_del_blocker(s->migration_blocker); |
| error_free(s->migration_blocker); |
| qemu_vfree(s->log.hdr); |
| s->log.hdr = NULL; |
| vhdx_region_unregister_all(s); |
| } |
| |
| static int vhdx_open(BlockDriverState *bs, QDict *options, int flags, |
| Error **errp) |
| { |
| BDRVVHDXState *s = bs->opaque; |
| int ret = 0; |
| uint32_t i; |
| uint64_t signature; |
| |
| |
| s->bat = NULL; |
| s->first_visible_write = true; |
| |
| qemu_co_mutex_init(&s->lock); |
| QLIST_INIT(&s->regions); |
| |
| /* validate the file signature */ |
| ret = bdrv_pread(bs->file, 0, &signature, sizeof(uint64_t)); |
| if (ret < 0) { |
| goto fail; |
| } |
| if (memcmp(&signature, "vhdxfile", 8)) { |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| /* This is used for any header updates, for the file_write_guid. |
| * The spec dictates that a new value should be used for the first |
| * header update */ |
| vhdx_guid_generate(&s->session_guid); |
| |
| ret = vhdx_parse_header(bs, s); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| ret = vhdx_parse_log(bs, s, &s->log_replayed_on_open, errp); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| ret = vhdx_open_region_tables(bs, s); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| ret = vhdx_parse_metadata(bs, s); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| s->block_size = s->params.block_size; |
| |
| /* the VHDX spec dictates that virtual_disk_size is always a multiple of |
| * logical_sector_size */ |
| bs->total_sectors = s->virtual_disk_size >> s->logical_sector_size_bits; |
| |
| vhdx_calc_bat_entries(s); |
| |
| s->bat_offset = s->bat_rt.file_offset; |
| |
| if (s->bat_entries > s->bat_rt.length / sizeof(VHDXBatEntry)) { |
| /* BAT allocation is not large enough for all entries */ |
| ret = -EINVAL; |
| goto fail; |
| } |
| |
| /* s->bat is freed in vhdx_close() */ |
| s->bat = qemu_blockalign(bs, s->bat_rt.length); |
| |
| ret = bdrv_pread(bs->file, s->bat_offset, s->bat, s->bat_rt.length); |
| if (ret < 0) { |
| goto fail; |
| } |
| |
| uint64_t payblocks = s->chunk_ratio; |
| /* endian convert, and verify populated BAT field file offsets against |
| * region table and log entries */ |
| for (i = 0; i < s->bat_entries; i++) { |
| le64_to_cpus(&s->bat[i]); |
| if (payblocks--) { |
| /* payload bat entries */ |
| if ((s->bat[i] & VHDX_BAT_STATE_BIT_MASK) == |
| PAYLOAD_BLOCK_FULLY_PRESENT) { |
| ret = vhdx_region_check(s, s->bat[i] & VHDX_BAT_FILE_OFF_MASK, |
| s->block_size); |
| if (ret < 0) { |
| goto fail; |
| } |
| } |
| } else { |
| payblocks = s->chunk_ratio; |
| /* Once differencing files are supported, verify sector bitmap |
| * blocks here */ |
| } |
| } |
| |
| if (flags & BDRV_O_RDWR) { |
| ret = vhdx_update_headers(bs, s, false, NULL); |
| if (ret < 0) { |
| goto fail; |
| } |
| } |
| |
| /* TODO: differencing files */ |
| |
| /* Disable migration when VHDX images are used */ |
| error_set(&s->migration_blocker, |
| QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED, |
| "vhdx", bs->device_name, "live migration"); |
| migrate_add_blocker(s->migration_blocker); |
| |
| return 0; |
| fail: |
| vhdx_close(bs); |
| return ret; |
| } |
| |
| static int vhdx_reopen_prepare(BDRVReopenState *state, |
| BlockReopenQueue *queue, Error **errp) |
| { |
| return 0; |
| } |
| |
| |
| /* |
| * Perform sector to block offset translations, to get various |
| * sector and file offsets into the image. See VHDXSectorInfo |
| */ |
| static void vhdx_block_translate(BDRVVHDXState *s, int64_t sector_num, |
| int nb_sectors, VHDXSectorInfo *sinfo) |
| { |
| uint32_t block_offset; |
| |
| sinfo->bat_idx = sector_num >> s->sectors_per_block_bits; |
| /* effectively a modulo - this gives us the offset into the block |
| * (in sector sizes) for our sector number */ |
| block_offset = sector_num - (sinfo->bat_idx << s->sectors_per_block_bits); |
| /* the chunk ratio gives us the interleaving of the sector |
| * bitmaps, so we need to advance our page block index by the |
| * sector bitmaps entry number */ |
| sinfo->bat_idx += sinfo->bat_idx >> s->chunk_ratio_bits; |
| |
| /* the number of sectors we can read/write in this cycle */ |
| sinfo->sectors_avail = s->sectors_per_block - block_offset; |
| |
| sinfo->bytes_left = sinfo->sectors_avail << s->logical_sector_size_bits; |
| |
| if (sinfo->sectors_avail > nb_sectors) { |
| sinfo->sectors_avail = nb_sectors; |
| } |
| |
| sinfo->bytes_avail = sinfo->sectors_avail << s->logical_sector_size_bits; |
| |
| sinfo->file_offset = s->bat[sinfo->bat_idx] & VHDX_BAT_FILE_OFF_MASK; |
| |
| sinfo->block_offset = block_offset << s->logical_sector_size_bits; |
| |
| /* The file offset must be past the header section, so must be > 0 */ |
| if (sinfo->file_offset == 0) { |
| return; |
| } |
| |
| /* block offset is the offset in vhdx logical sectors, in |
| * the payload data block. Convert that to a byte offset |
| * in the block, and add in the payload data block offset |
| * in the file, in bytes, to get the final read address */ |
| |
| sinfo->file_offset += sinfo->block_offset; |
| } |
| |
| |
| static int vhdx_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) |
| { |
| BDRVVHDXState *s = bs->opaque; |
| |
| bdi->cluster_size = s->block_size; |
| |
| bdi->unallocated_blocks_are_zero = |
| (s->params.data_bits & VHDX_PARAMS_HAS_PARENT) == 0; |
| |
| return 0; |
| } |
| |
| |
| static coroutine_fn int vhdx_co_readv(BlockDriverState *bs, int64_t sector_num, |
| int nb_sectors, QEMUIOVector *qiov) |
| { |
| BDRVVHDXState *s = bs->opaque; |
| int ret = 0; |
| VHDXSectorInfo sinfo; |
| uint64_t bytes_done = 0; |
| QEMUIOVector hd_qiov; |
| |
| qemu_iovec_init(&hd_qiov, qiov->niov); |
| |
| qemu_co_mutex_lock(&s->lock); |
| |
| while (nb_sectors > 0) { |
| /* We are a differencing file, so we need to inspect the sector bitmap |
| * to see if we have the data or not */ |
| if (s->params.data_bits & VHDX_PARAMS_HAS_PARENT) { |
| /* not supported yet */ |
| ret = -ENOTSUP; |
| goto exit; |
| } else { |
| vhdx_block_translate(s, sector_num, nb_sectors, &sinfo); |
| |
| qemu_iovec_reset(&hd_qiov); |
| qemu_iovec_concat(&hd_qiov, qiov, bytes_done, sinfo.bytes_avail); |
| |
| /* check the payload block state */ |
| switch (s->bat[sinfo.bat_idx] & VHDX_BAT_STATE_BIT_MASK) { |
| case PAYLOAD_BLOCK_NOT_PRESENT: /* fall through */ |
| case PAYLOAD_BLOCK_UNDEFINED: /* fall through */ |
| case PAYLOAD_BLOCK_UNMAPPED: /* fall through */ |
| case PAYLOAD_BLOCK_ZERO: |
| /* return zero */ |
| qemu_iovec_memset(&hd_qiov, 0, 0, sinfo.bytes_avail); |
| break; |
| case PAYLOAD_BLOCK_FULLY_PRESENT: |
| qemu_co_mutex_unlock(&s->lock); |
| ret = bdrv_co_readv(bs->file, |
| sinfo.file_offset >> BDRV_SECTOR_BITS, |
| sinfo.sectors_avail, &hd_qiov); |
| qemu_co_mutex_lock(&s->lock); |
| if (ret < 0) { |
| goto exit; |
| } |
| break; |
| case PAYLOAD_BLOCK_PARTIALLY_PRESENT: |
| /* we don't yet support difference files, fall through |
| * to error */ |
| default: |
| ret = -EIO; |
| goto exit; |
| break; |
| } |
| nb_sectors -= sinfo.sectors_avail; |
| sector_num += sinfo.sectors_avail; |
| bytes_done += sinfo.bytes_avail; |
| } |
| } |
| ret = 0; |
| exit: |
| qemu_co_mutex_unlock(&s->lock); |
| qemu_iovec_destroy(&hd_qiov); |
| return ret; |
| } |
| |
| /* |
| * Allocate a new payload block at the end of the file. |
| * |
| * Allocation will happen at 1MB alignment inside the file |
| * |
| * Returns the file offset start of the new payload block |
| */ |
| static int vhdx_allocate_block(BlockDriverState *bs, BDRVVHDXState *s, |
| uint64_t *new_offset) |
| { |
| *new_offset = bdrv_getlength(bs->file); |
| |
| /* per the spec, the address for a block is in units of 1MB */ |
| *new_offset = ROUND_UP(*new_offset, 1024 * 1024); |
| |
| return bdrv_truncate(bs->file, *new_offset + s->block_size); |
| } |
| |
| /* |
| * Update the BAT table entry with the new file offset, and the new entry |
| * state */ |
| static void vhdx_update_bat_table_entry(BlockDriverState *bs, BDRVVHDXState *s, |
| VHDXSectorInfo *sinfo, |
| uint64_t *bat_entry_le, |
| uint64_t *bat_offset, int state) |
| { |
| /* The BAT entry is a uint64, with 44 bits for the file offset in units of |
| * 1MB, and 3 bits for the block state. */ |
| s->bat[sinfo->bat_idx] = sinfo->file_offset; |
| |
| s->bat[sinfo->bat_idx] |= state & VHDX_BAT_STATE_BIT_MASK; |
| |
| *bat_entry_le = cpu_to_le64(s->bat[sinfo->bat_idx]); |
| *bat_offset = s->bat_offset + sinfo->bat_idx * sizeof(VHDXBatEntry); |
| |
| } |
| |
| /* Per the spec, on the first write of guest-visible data to the file the |
| * data write guid must be updated in the header */ |
| int vhdx_user_visible_write(BlockDriverState *bs, BDRVVHDXState *s) |
| { |
| int ret = 0; |
| if (s->first_visible_write) { |
| s->first_visible_write = false; |
| ret = vhdx_update_headers(bs, s, true, NULL); |
| } |
| return ret; |
| } |
| |
| static coroutine_fn int vhdx_co_writev(BlockDriverState *bs, int64_t sector_num, |
| int nb_sectors, QEMUIOVector *qiov) |
| { |
| int ret = -ENOTSUP; |
| BDRVVHDXState *s = bs->opaque; |
| VHDXSectorInfo sinfo; |
| uint64_t bytes_done = 0; |
| uint64_t bat_entry = 0; |
| uint64_t bat_entry_offset = 0; |
| QEMUIOVector hd_qiov; |
| struct iovec iov1 = { 0 }; |
| struct iovec iov2 = { 0 }; |
| int sectors_to_write; |
| int bat_state; |
| uint64_t bat_prior_offset = 0; |
| bool bat_update = false; |
| |
| qemu_iovec_init(&hd_qiov, qiov->niov); |
| |
| qemu_co_mutex_lock(&s->lock); |
| |
| ret = vhdx_user_visible_write(bs, s); |
| if (ret < 0) { |
| goto exit; |
| } |
| |
| while (nb_sectors > 0) { |
| bool use_zero_buffers = false; |
| bat_update = false; |
| if (s->params.data_bits & VHDX_PARAMS_HAS_PARENT) { |
| /* not supported yet */ |
| ret = -ENOTSUP; |
| goto exit; |
| } else { |
| vhdx_block_translate(s, sector_num, nb_sectors, &sinfo); |
| sectors_to_write = sinfo.sectors_avail; |
| |
| qemu_iovec_reset(&hd_qiov); |
| /* check the payload block state */ |
| bat_state = s->bat[sinfo.bat_idx] & VHDX_BAT_STATE_BIT_MASK; |
| switch (bat_state) { |
| case PAYLOAD_BLOCK_ZERO: |
| /* in this case, we need to preserve zero writes for |
| * data that is not part of this write, so we must pad |
| * the rest of the buffer to zeroes */ |
| |
| /* if we are on a posix system with ftruncate() that extends |
| * a file, then it is zero-filled for us. On Win32, the raw |
| * layer uses SetFilePointer and SetFileEnd, which does not |
| * zero fill AFAIK */ |
| |
| /* Queue another write of zero buffers if the underlying file |
| * does not zero-fill on file extension */ |
| |
| if (bdrv_has_zero_init(bs->file) == 0) { |
| use_zero_buffers = true; |
| |
| /* zero fill the front, if any */ |
| if (sinfo.block_offset) { |
| iov1.iov_len = sinfo.block_offset; |
| iov1.iov_base = qemu_blockalign(bs, iov1.iov_len); |
| memset(iov1.iov_base, 0, iov1.iov_len); |
| qemu_iovec_concat_iov(&hd_qiov, &iov1, 1, 0, |
| sinfo.block_offset); |
| sectors_to_write += iov1.iov_len >> BDRV_SECTOR_BITS; |
| } |
| |
| /* our actual data */ |
| qemu_iovec_concat(&hd_qiov, qiov, bytes_done, |
| sinfo.bytes_avail); |
| |
| /* zero fill the back, if any */ |
| if ((sinfo.bytes_avail - sinfo.block_offset) < |
| s->block_size) { |
| iov2.iov_len = s->block_size - |
| (sinfo.bytes_avail + sinfo.block_offset); |
| iov2.iov_base = qemu_blockalign(bs, iov2.iov_len); |
| memset(iov2.iov_base, 0, iov2.iov_len); |
| qemu_iovec_concat_iov(&hd_qiov, &iov2, 1, 0, |
| sinfo.block_offset); |
| sectors_to_write += iov2.iov_len >> BDRV_SECTOR_BITS; |
| } |
| } |
| |
| /* fall through */ |
| case PAYLOAD_BLOCK_NOT_PRESENT: /* fall through */ |
| case PAYLOAD_BLOCK_UNMAPPED: /* fall through */ |
| case PAYLOAD_BLOCK_UNDEFINED: /* fall through */ |
| bat_prior_offset = sinfo.file_offset; |
| ret = vhdx_allocate_block(bs, s, &sinfo.file_offset); |
| if (ret < 0) { |
| goto exit; |
| } |
| /* once we support differencing files, this may also be |
| * partially present */ |
| /* update block state to the newly specified state */ |
| vhdx_update_bat_table_entry(bs, s, &sinfo, &bat_entry, |
| &bat_entry_offset, |
| PAYLOAD_BLOCK_FULLY_PRESENT); |
| bat_update = true; |
| /* since we just allocated a block, file_offset is the |
| * beginning of the payload block. It needs to be the |
| * write address, which includes the offset into the block */ |
| if (!use_zero_buffers) { |
| sinfo.file_offset += sinfo.block_offset; |
| } |
| /* fall through */ |
| case PAYLOAD_BLOCK_FULLY_PRESENT: |
| /* if the file offset address is in the header zone, |
| * there is a problem */ |
| if (sinfo.file_offset < (1024 * 1024)) { |
| ret = -EFAULT; |
| goto error_bat_restore; |
| } |
| |
| if (!use_zero_buffers) { |
| qemu_iovec_concat(&hd_qiov, qiov, bytes_done, |
| sinfo.bytes_avail); |
| } |
| /* block exists, so we can just overwrite it */ |
| qemu_co_mutex_unlock(&s->lock); |
| ret = bdrv_co_writev(bs->file, |
| sinfo.file_offset >> BDRV_SECTOR_BITS, |
| sectors_to_write, &hd_qiov); |
| qemu_co_mutex_lock(&s->lock); |
| if (ret < 0) { |
| goto error_bat_restore; |
| } |
| break; |
| case PAYLOAD_BLOCK_PARTIALLY_PRESENT: |
| /* we don't yet support difference files, fall through |
| * to error */ |
| default: |
| ret = -EIO; |
| goto exit; |
| break; |
| } |
| |
| if (bat_update) { |
| /* this will update the BAT entry into the log journal, and |
| * then flush the log journal out to disk */ |
| ret = vhdx_log_write_and_flush(bs, s, &bat_entry, |
| sizeof(VHDXBatEntry), |
| bat_entry_offset); |
| if (ret < 0) { |
| goto exit; |
| } |
| } |
| |
| nb_sectors -= sinfo.sectors_avail; |
| sector_num += sinfo.sectors_avail; |
| bytes_done += sinfo.bytes_avail; |
| |
| } |
| } |
| |
| goto exit; |
| |
| error_bat_restore: |
| if (bat_update) { |
| /* keep metadata in sync, and restore the bat entry state |
| * if error. */ |
| sinfo.file_offset = bat_prior_offset; |
| vhdx_update_bat_table_entry(bs, s, &sinfo, &bat_entry, |
| &bat_entry_offset, bat_state); |
| } |
| exit: |
| qemu_vfree(iov1.iov_base); |
| qemu_vfree(iov2.iov_base); |
| qemu_co_mutex_unlock(&s->lock); |
| qemu_iovec_destroy(&hd_qiov); |
| return ret; |
| } |
| |
| |
| |
| /* |
| * Create VHDX Headers |
| * |
| * There are 2 headers, and the highest sequence number will represent |
| * the active header |
| */ |
| static int vhdx_create_new_headers(BlockDriverState *bs, uint64_t image_size, |
| uint32_t log_size) |
| { |
| int ret = 0; |
| VHDXHeader *hdr = NULL; |
| |
| hdr = g_malloc0(sizeof(VHDXHeader)); |
| |
| hdr->signature = VHDX_HEADER_SIGNATURE; |
| hdr->sequence_number = g_random_int(); |
| hdr->log_version = 0; |
| hdr->version = 1; |
| hdr->log_length = log_size; |
| hdr->log_offset = VHDX_HEADER_SECTION_END; |
| vhdx_guid_generate(&hdr->file_write_guid); |
| vhdx_guid_generate(&hdr->data_write_guid); |
| |
| ret = vhdx_write_header(bs, hdr, VHDX_HEADER1_OFFSET, false); |
| if (ret < 0) { |
| goto exit; |
| } |
| hdr->sequence_number++; |
| ret = vhdx_write_header(bs, hdr, VHDX_HEADER2_OFFSET, false); |
| if (ret < 0) { |
| goto exit; |
| } |
| |
| exit: |
| g_free(hdr); |
| return ret; |
| } |
| |
| |
| /* |
| * Create the Metadata entries. |
| * |
| * For more details on the entries, see section 3.5 (pg 29) in the |
| * VHDX 1.00 specification. |
| * |
| * We support 5 metadata entries (all required by spec): |
| * File Parameters, |
| * Virtual Disk Size, |
| * Page 83 Data, |
| * Logical Sector Size, |
| * Physical Sector Size |
| * |
| * The first 64KB of the Metadata section is reserved for the metadata |
| * header and entries; beyond that, the metadata items themselves reside. |
| */ |
| static int vhdx_create_new_metadata(BlockDriverState *bs, |
| uint64_t image_size, |
| uint32_t block_size, |
| uint32_t sector_size, |
| uint64_t metadata_offset, |
| VHDXImageType type) |
| { |
| int ret = 0; |
| uint32_t offset = 0; |
| void *buffer = NULL; |
| void *entry_buffer; |
| VHDXMetadataTableHeader *md_table;; |
| VHDXMetadataTableEntry *md_table_entry; |
| |
| /* Metadata entries */ |
| VHDXFileParameters *mt_file_params; |
| VHDXVirtualDiskSize *mt_virtual_size; |
| VHDXPage83Data *mt_page83; |
| VHDXVirtualDiskLogicalSectorSize *mt_log_sector_size; |
| VHDXVirtualDiskPhysicalSectorSize *mt_phys_sector_size; |
| |
| entry_buffer = g_malloc0(sizeof(VHDXFileParameters) + |
| sizeof(VHDXVirtualDiskSize) + |
| sizeof(VHDXPage83Data) + |
| sizeof(VHDXVirtualDiskLogicalSectorSize) + |
| sizeof(VHDXVirtualDiskPhysicalSectorSize)); |
| |
| mt_file_params = entry_buffer; |
| offset += sizeof(VHDXFileParameters); |
| mt_virtual_size = entry_buffer + offset; |
| offset += sizeof(VHDXVirtualDiskSize); |
| mt_page83 = entry_buffer + offset; |
| offset += sizeof(VHDXPage83Data); |
| mt_log_sector_size = entry_buffer + offset; |
| offset += sizeof(VHDXVirtualDiskLogicalSectorSize); |
| mt_phys_sector_size = entry_buffer + offset; |
| |
| mt_file_params->block_size = cpu_to_le32(block_size); |
| if (type == VHDX_TYPE_FIXED) { |
| mt_file_params->data_bits |= VHDX_PARAMS_LEAVE_BLOCKS_ALLOCED; |
| cpu_to_le32s(&mt_file_params->data_bits); |
| } |
| |
| vhdx_guid_generate(&mt_page83->page_83_data); |
| cpu_to_leguids(&mt_page83->page_83_data); |
| mt_virtual_size->virtual_disk_size = cpu_to_le64(image_size); |
| mt_log_sector_size->logical_sector_size = cpu_to_le32(sector_size); |
| mt_phys_sector_size->physical_sector_size = cpu_to_le32(sector_size); |
| |
| buffer = g_malloc0(VHDX_HEADER_BLOCK_SIZE); |
| md_table = buffer; |
| |
| md_table->signature = VHDX_METADATA_SIGNATURE; |
| md_table->entry_count = 5; |
| vhdx_metadata_header_le_export(md_table); |
| |
| |
| /* This will reference beyond the reserved table portion */ |
| offset = 64 * KiB; |
| |
| md_table_entry = buffer + sizeof(VHDXMetadataTableHeader); |
| |
| md_table_entry[0].item_id = file_param_guid; |
| md_table_entry[0].offset = offset; |
| md_table_entry[0].length = sizeof(VHDXFileParameters); |
| md_table_entry[0].data_bits |= VHDX_META_FLAGS_IS_REQUIRED; |
| offset += md_table_entry[0].length; |
| vhdx_metadata_entry_le_export(&md_table_entry[0]); |
| |
| md_table_entry[1].item_id = virtual_size_guid; |
| md_table_entry[1].offset = offset; |
| md_table_entry[1].length = sizeof(VHDXVirtualDiskSize); |
| md_table_entry[1].data_bits |= VHDX_META_FLAGS_IS_REQUIRED | |
| VHDX_META_FLAGS_IS_VIRTUAL_DISK; |
| offset += md_table_entry[1].length; |
| vhdx_metadata_entry_le_export(&md_table_entry[1]); |
| |
| md_table_entry[2].item_id = page83_guid; |
| md_table_entry[2].offset = offset; |
| md_table_entry[2].length = sizeof(VHDXPage83Data); |
| md_table_entry[2].data_bits |= VHDX_META_FLAGS_IS_REQUIRED | |
| VHDX_META_FLAGS_IS_VIRTUAL_DISK; |
| offset += md_table_entry[2].length; |
| vhdx_metadata_entry_le_export(&md_table_entry[2]); |
| |
| md_table_entry[3].item_id = logical_sector_guid; |
| md_table_entry[3].offset = offset; |
| md_table_entry[3].length = sizeof(VHDXVirtualDiskLogicalSectorSize); |
| md_table_entry[3].data_bits |= VHDX_META_FLAGS_IS_REQUIRED | |
| VHDX_META_FLAGS_IS_VIRTUAL_DISK; |
| offset += md_table_entry[3].length; |
| vhdx_metadata_entry_le_export(&md_table_entry[3]); |
| |
| md_table_entry[4].item_id = phys_sector_guid; |
| md_table_entry[4].offset = offset; |
| md_table_entry[4].length = sizeof(VHDXVirtualDiskPhysicalSectorSize); |
| md_table_entry[4].data_bits |= VHDX_META_FLAGS_IS_REQUIRED | |
| VHDX_META_FLAGS_IS_VIRTUAL_DISK; |
| vhdx_metadata_entry_le_export(&md_table_entry[4]); |
| |
| ret = bdrv_pwrite(bs, metadata_offset, buffer, VHDX_HEADER_BLOCK_SIZE); |
| if (ret < 0) { |
| goto exit; |
| } |
| |
| ret = bdrv_pwrite(bs, metadata_offset + (64 * KiB), entry_buffer, |
| VHDX_HEADER_BLOCK_SIZE); |
| if (ret < 0) { |
| goto exit; |
| } |
| |
| |
| exit: |
| g_free(buffer); |
| g_free(entry_buffer); |
| return ret; |
| } |
| |
| /* This create the actual BAT itself. We currently only support |
| * 'Dynamic' and 'Fixed' image types. |
| * |
| * Dynamic images: default state of the BAT is all zeroes. |
| * |
| * Fixed images: default state of the BAT is fully populated, with |
| * file offsets and state PAYLOAD_BLOCK_FULLY_PRESENT. |
| */ |
| static int vhdx_create_bat(BlockDriverState *bs, BDRVVHDXState *s, |
| uint64_t image_size, VHDXImageType type, |
| bool use_zero_blocks, VHDXRegionTableEntry *rt_bat) |
| { |
| int ret = 0; |
| uint64_t data_file_offset; |
| uint64_t total_sectors = 0; |
| uint64_t sector_num = 0; |
| uint64_t unused; |
| int block_state; |
| VHDXSectorInfo sinfo; |
| |
| assert(s->bat == NULL); |
| |
| /* this gives a data start after BAT/bitmap entries, and well |
| * past any metadata entries (with a 4 MB buffer for future |
| * expansion */ |
| data_file_offset = rt_bat->file_offset + rt_bat->length + 5 * MiB; |
| total_sectors = image_size >> s->logical_sector_size_bits; |
| |
| if (type == VHDX_TYPE_DYNAMIC) { |
| /* All zeroes, so we can just extend the file - the end of the BAT |
| * is the furthest thing we have written yet */ |
| ret = bdrv_truncate(bs, data_file_offset); |
| if (ret < 0) { |
| goto exit; |
| } |
| } else if (type == VHDX_TYPE_FIXED) { |
| ret = bdrv_truncate(bs, data_file_offset + image_size); |
| if (ret < 0) { |
| goto exit; |
| } |
| } else { |
| ret = -ENOTSUP; |
| goto exit; |
| } |
| |
| if (type == VHDX_TYPE_FIXED || |
| use_zero_blocks || |
| bdrv_has_zero_init(bs) == 0) { |
| /* for a fixed file, the default BAT entry is not zero */ |
| s->bat = g_malloc0(rt_bat->length); |
| block_state = type == VHDX_TYPE_FIXED ? PAYLOAD_BLOCK_FULLY_PRESENT : |
| PAYLOAD_BLOCK_NOT_PRESENT; |
| block_state = use_zero_blocks ? PAYLOAD_BLOCK_ZERO : block_state; |
| /* fill the BAT by emulating sector writes of sectors_per_block size */ |
| while (sector_num < total_sectors) { |
| vhdx_block_translate(s, sector_num, s->sectors_per_block, &sinfo); |
| sinfo.file_offset = data_file_offset + |
| (sector_num << s->logical_sector_size_bits); |
| sinfo.file_offset = ROUND_UP(sinfo.file_offset, MiB); |
| vhdx_update_bat_table_entry(bs, s, &sinfo, &unused, &unused, |
| block_state); |
| cpu_to_le64s(&s->bat[sinfo.bat_idx]); |
| sector_num += s->sectors_per_block; |
| } |
| ret = bdrv_pwrite(bs, rt_bat->file_offset, s->bat, rt_bat->length); |
| if (ret < 0) { |
| goto exit; |
| } |
| } |
| |
| |
| |
| exit: |
| g_free(s->bat); |
| return ret; |
| } |
| |
| /* Creates the region table header, and region table entries. |
| * There are 2 supported region table entries: BAT, and Metadata/ |
| * |
| * As the calculations for the BAT region table are also needed |
| * to create the BAT itself, we will also cause the BAT to be |
| * created. |
| */ |
| static int vhdx_create_new_region_table(BlockDriverState *bs, |
| uint64_t image_size, |
| uint32_t block_size, |
| uint32_t sector_size, |
| uint32_t log_size, |
| bool use_zero_blocks, |
| VHDXImageType type, |
| uint64_t *metadata_offset) |
| { |
| int ret = 0; |
| uint32_t offset = 0; |
| void *buffer = NULL; |
| BDRVVHDXState *s = NULL; |
| VHDXRegionTableHeader *region_table; |
| VHDXRegionTableEntry *rt_bat; |
| VHDXRegionTableEntry *rt_metadata; |
| |
| assert(metadata_offset != NULL); |
| |
| /* Populate enough of the BDRVVHDXState to be able to use the |
| * pre-existing BAT calculation, translation, and update functions */ |
| s = g_malloc0(sizeof(BDRVVHDXState)); |
| |
| s->chunk_ratio = (VHDX_MAX_SECTORS_PER_BLOCK) * |
| (uint64_t) sector_size / (uint64_t) block_size; |
| |
| s->sectors_per_block = block_size / sector_size; |
| s->virtual_disk_size = image_size; |
| s->block_size = block_size; |
| s->logical_sector_size = sector_size; |
| |
| vhdx_set_shift_bits(s); |
| |
| vhdx_calc_bat_entries(s); |
| |
| /* At this point the VHDX state is populated enough for creation */ |
| |
| /* a single buffer is used so we can calculate the checksum over the |
| * entire 64KB block */ |
| buffer = g_malloc0(VHDX_HEADER_BLOCK_SIZE); |
| region_table = buffer; |
| offset += sizeof(VHDXRegionTableHeader); |
| rt_bat = buffer + offset; |
| offset += sizeof(VHDXRegionTableEntry); |
| rt_metadata = buffer + offset; |
| |
| region_table->signature = VHDX_REGION_SIGNATURE; |
| region_table->entry_count = 2; /* BAT and Metadata */ |
| |
| rt_bat->guid = bat_guid; |
| rt_bat->length = ROUND_UP(s->bat_entries * sizeof(VHDXBatEntry), MiB); |
| rt_bat->file_offset = ROUND_UP(VHDX_HEADER_SECTION_END + log_size, MiB); |
| s->bat_offset = rt_bat->file_offset; |
| |
| rt_metadata->guid = metadata_guid; |
| rt_metadata->file_offset = ROUND_UP(rt_bat->file_offset + rt_bat->length, |
| MiB); |
| rt_metadata->length = 1 * MiB; /* min size, and more than enough */ |
| *metadata_offset = rt_metadata->file_offset; |
| |
| vhdx_update_checksum(buffer, VHDX_HEADER_BLOCK_SIZE, |
| offsetof(VHDXRegionTableHeader, checksum)); |
| |
| |
| /* The region table gives us the data we need to create the BAT, |
| * so do that now */ |
| ret = vhdx_create_bat(bs, s, image_size, type, use_zero_blocks, rt_bat); |
| |
| /* Now write out the region headers to disk */ |
| vhdx_region_header_le_export(region_table); |
| vhdx_region_entry_le_export(rt_bat); |
| vhdx_region_entry_le_export(rt_metadata); |
| |
| ret = bdrv_pwrite(bs, VHDX_REGION_TABLE_OFFSET, buffer, |
| VHDX_HEADER_BLOCK_SIZE); |
| if (ret < 0) { |
| goto exit; |
| } |
| |
| ret = bdrv_pwrite(bs, VHDX_REGION_TABLE2_OFFSET, buffer, |
| VHDX_HEADER_BLOCK_SIZE); |
| if (ret < 0) { |
| goto exit; |
| } |
| |
| |
| exit: |
| g_free(s); |
| g_free(buffer); |
| return ret; |
| } |
| |
| /* We need to create the following elements: |
| * |
| * .-----------------------------------------------------------------. |
| * | (A) | (B) | (C) | (D) | (E) | |
| * | File ID | Header1 | Header 2 | Region Tbl 1 | Region Tbl 2 | |
| * | | | | | | |
| * .-----------------------------------------------------------------. |
| * 0 64KB 128KB 192KB 256KB 320KB |
| * |
| * |
| * .---- ~ ----------- ~ ------------ ~ ---------------- ~ -----------. |
| * | (F) | (G) | (H) | | |
| * | Journal Log | BAT / Bitmap | Metadata | .... data ...... | |
| * | | | | | |
| * .---- ~ ----------- ~ ------------ ~ ---------------- ~ -----------. |
| * 1MB |
| */ |
| static int vhdx_create(const char *filename, QEMUOptionParameter *options, |
| Error **errp) |
| { |
| int ret = 0; |
| uint64_t image_size = (uint64_t) 2 * GiB; |
| uint32_t log_size = 1 * MiB; |
| uint32_t block_size = 0; |
| uint64_t signature; |
| uint64_t metadata_offset; |
| bool use_zero_blocks = false; |
| |
| gunichar2 *creator = NULL; |
| glong creator_items; |
| BlockDriverState *bs; |
| const char *type = NULL; |
| VHDXImageType image_type; |
| Error *local_err = NULL; |
| |
| while (options && options->name) { |
| if (!strcmp(options->name, BLOCK_OPT_SIZE)) { |
| image_size = options->value.n; |
| } else if (!strcmp(options->name, VHDX_BLOCK_OPT_LOG_SIZE)) { |
| log_size = options->value.n; |
| } else if (!strcmp(options->name, VHDX_BLOCK_OPT_BLOCK_SIZE)) { |
| block_size = options->value.n; |
| } else if (!strcmp(options->name, BLOCK_OPT_SUBFMT)) { |
| type = options->value.s; |
| } else if (!strcmp(options->name, VHDX_BLOCK_OPT_ZERO)) { |
| use_zero_blocks = options->value.n != 0; |
| } |
| options++; |
| } |
| |
| if (image_size > VHDX_MAX_IMAGE_SIZE) { |
| error_setg_errno(errp, EINVAL, "Image size too large; max of 64TB"); |
| ret = -EINVAL; |
| goto exit; |
| } |
| |
| if (type == NULL) { |
| type = "dynamic"; |
| } |
| |
| if (!strcmp(type, "dynamic")) { |
| image_type = VHDX_TYPE_DYNAMIC; |
| } else if (!strcmp(type, "fixed")) { |
| image_type = VHDX_TYPE_FIXED; |
| } else if (!strcmp(type, "differencing")) { |
| error_setg_errno(errp, ENOTSUP, |
| "Differencing files not yet supported"); |
| ret = -ENOTSUP; |
| goto exit; |
| } else { |
| ret = -EINVAL; |
| goto exit; |
| } |
| |
| /* These are pretty arbitrary, and mainly designed to keep the BAT |
| * size reasonable to load into RAM */ |
| if (block_size == 0) { |
| if (image_size > 32 * TiB) { |
| block_size = 64 * MiB; |
| } else if (image_size > (uint64_t) 100 * GiB) { |
| block_size = 32 * MiB; |
| } else if (image_size > 1 * GiB) { |
| block_size = 16 * MiB; |
| } else { |
| block_size = 8 * MiB; |
| } |
| } |
| |
| |
| /* make the log size close to what was specified, but must be |
| * min 1MB, and multiple of 1MB */ |
| log_size = ROUND_UP(log_size, MiB); |
| |
| block_size = ROUND_UP(block_size, MiB); |
| block_size = block_size > VHDX_BLOCK_SIZE_MAX ? VHDX_BLOCK_SIZE_MAX : |
| block_size; |
| |
| ret = bdrv_create_file(filename, options, &local_err); |
| if (ret < 0) { |
| error_propagate(errp, local_err); |
| goto exit; |
| } |
| |
| ret = bdrv_file_open(&bs, filename, NULL, NULL, BDRV_O_RDWR, &local_err); |
| if (ret < 0) { |
| error_propagate(errp, local_err); |
| goto exit; |
| } |
| |
| /* Create (A) */ |
| |
| /* The creator field is optional, but may be useful for |
| * debugging / diagnostics */ |
| creator = g_utf8_to_utf16("QEMU v" QEMU_VERSION, -1, NULL, |
| &creator_items, NULL); |
| signature = cpu_to_le64(VHDX_FILE_SIGNATURE); |
| bdrv_pwrite(bs, VHDX_FILE_ID_OFFSET, &signature, sizeof(signature)); |
| if (ret < 0) { |
| goto delete_and_exit; |
| } |
| if (creator) { |
| bdrv_pwrite(bs, VHDX_FILE_ID_OFFSET + sizeof(signature), creator, |
| creator_items * sizeof(gunichar2)); |
| if (ret < 0) { |
| goto delete_and_exit; |
| } |
| } |
| |
| |
| /* Creates (B),(C) */ |
| ret = vhdx_create_new_headers(bs, image_size, log_size); |
| if (ret < 0) { |
| goto delete_and_exit; |
| } |
| |
| /* Creates (D),(E),(G) explicitly. (F) created as by-product */ |
| ret = vhdx_create_new_region_table(bs, image_size, block_size, 512, |
| log_size, use_zero_blocks, image_type, |
| &metadata_offset); |
| if (ret < 0) { |
| goto delete_and_exit; |
| } |
| |
| /* Creates (H) */ |
| ret = vhdx_create_new_metadata(bs, image_size, block_size, 512, |
| metadata_offset, image_type); |
| if (ret < 0) { |
| goto delete_and_exit; |
| } |
| |
| |
| |
| delete_and_exit: |
| bdrv_unref(bs); |
| exit: |
| g_free(creator); |
| return ret; |
| } |
| |
| /* If opened r/w, the VHDX driver will automatically replay the log, |
| * if one is present, inside the vhdx_open() call. |
| * |
| * If qemu-img check -r all is called, the image is automatically opened |
| * r/w and any log has already been replayed, so there is nothing (currently) |
| * for us to do here |
| */ |
| static int vhdx_check(BlockDriverState *bs, BdrvCheckResult *result, |
| BdrvCheckMode fix) |
| { |
| BDRVVHDXState *s = bs->opaque; |
| |
| if (s->log_replayed_on_open) { |
| result->corruptions_fixed++; |
| } |
| return 0; |
| } |
| |
| static QEMUOptionParameter vhdx_create_options[] = { |
| { |
| .name = BLOCK_OPT_SIZE, |
| .type = OPT_SIZE, |
| .help = "Virtual disk size; max of 64TB." |
| }, |
| { |
| .name = VHDX_BLOCK_OPT_LOG_SIZE, |
| .type = OPT_SIZE, |
| .value.n = 1 * MiB, |
| .help = "Log size; min 1MB." |
| }, |
| { |
| .name = VHDX_BLOCK_OPT_BLOCK_SIZE, |
| .type = OPT_SIZE, |
| .value.n = 0, |
| .help = "Block Size; min 1MB, max 256MB. " \ |
| "0 means auto-calculate based on image size." |
| }, |
| { |
| .name = BLOCK_OPT_SUBFMT, |
| .type = OPT_STRING, |
| .help = "VHDX format type, can be either 'dynamic' or 'fixed'. "\ |
| "Default is 'dynamic'." |
| }, |
| { |
| .name = VHDX_BLOCK_OPT_ZERO, |
| .type = OPT_FLAG, |
| .help = "Force use of payload blocks of type 'ZERO'. Non-standard." |
| }, |
| { NULL } |
| }; |
| |
| static BlockDriver bdrv_vhdx = { |
| .format_name = "vhdx", |
| .instance_size = sizeof(BDRVVHDXState), |
| .bdrv_probe = vhdx_probe, |
| .bdrv_open = vhdx_open, |
| .bdrv_close = vhdx_close, |
| .bdrv_reopen_prepare = vhdx_reopen_prepare, |
| .bdrv_co_readv = vhdx_co_readv, |
| .bdrv_co_writev = vhdx_co_writev, |
| .bdrv_create = vhdx_create, |
| .bdrv_get_info = vhdx_get_info, |
| .bdrv_check = vhdx_check, |
| |
| .create_options = vhdx_create_options, |
| }; |
| |
| static void bdrv_vhdx_init(void) |
| { |
| bdrv_register(&bdrv_vhdx); |
| } |
| |
| block_init(bdrv_vhdx_init); |