diff options
Diffstat (limited to 'block/vhdx.h')
| -rw-r--r-- | block/vhdx.h | 190 |
1 files changed, 158 insertions, 32 deletions
diff --git a/block/vhdx.h b/block/vhdx.h index fb687ed2d..0b74924ce 100644 --- a/block/vhdx.h +++ b/block/vhdx.h @@ -6,9 +6,9 @@ * Authors: * Jeff Cody <jcody@redhat.com> * - * This is based on the "VHDX Format Specification v0.95", published 4/12/2012 + * 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=29681 + * 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. @@ -17,6 +17,10 @@ #ifndef BLOCK_VHDX_H #define BLOCK_VHDX_H +#include "qemu/units.h" + +#define DEFAULT_LOG_SIZE 1048576 /* 1MiB */ +/* Note: can't use 1 * MiB, because it's passed to stringify() */ /* Structures and fields present in the VHDX file */ @@ -30,14 +34,15 @@ * 0.........64KB...........128KB........192KB..........256KB................1MB */ -#define VHDX_HEADER_BLOCK_SIZE (64*1024) +#define VHDX_HEADER_BLOCK_SIZE (64 * KiB) #define VHDX_FILE_ID_OFFSET 0 -#define VHDX_HEADER1_OFFSET (VHDX_HEADER_BLOCK_SIZE*1) -#define VHDX_HEADER2_OFFSET (VHDX_HEADER_BLOCK_SIZE*2) -#define VHDX_REGION_TABLE_OFFSET (VHDX_HEADER_BLOCK_SIZE*3) - +#define VHDX_HEADER1_OFFSET (VHDX_HEADER_BLOCK_SIZE * 1) +#define VHDX_HEADER2_OFFSET (VHDX_HEADER_BLOCK_SIZE * 2) +#define VHDX_REGION_TABLE_OFFSET (VHDX_HEADER_BLOCK_SIZE * 3) +#define VHDX_REGION_TABLE2_OFFSET (VHDX_HEADER_BLOCK_SIZE * 4) +#define VHDX_HEADER_SECTION_END (1 * MiB) /* * A note on the use of MS-GUID fields. For more details on the GUID, * please see: https://en.wikipedia.org/wiki/Globally_unique_identifier. @@ -55,10 +60,11 @@ /* These structures are ones that are defined in the VHDX specification * document */ +#define VHDX_FILE_SIGNATURE 0x656C696678646876ULL /* "vhdxfile" in ASCII */ typedef struct VHDXFileIdentifier { uint64_t signature; /* "vhdxfile" in ASCII */ uint16_t creator[256]; /* optional; utf-16 string to identify - the vhdx file creator. Diagnotistic + the vhdx file creator. Diagnostic only */ } VHDXFileIdentifier; @@ -67,7 +73,7 @@ typedef struct VHDXFileIdentifier { * Microsoft is not just 16 bytes though - it is a structure that is defined, * so we need to follow it here so that endianness does not trip us up */ -typedef struct MSGUID { +typedef struct QEMU_PACKED MSGUID { uint32_t data1; uint16_t data2; uint16_t data3; @@ -77,14 +83,15 @@ typedef struct MSGUID { #define guid_eq(a, b) \ (memcmp(&(a), &(b), sizeof(MSGUID)) == 0) -#define VHDX_HEADER_SIZE (4*1024) /* although the vhdx_header struct in disk - is only 582 bytes, for purposes of crc - the header is the first 4KB of the 64KB - block */ +#define VHDX_HEADER_SIZE (4 * KiB) /* although the vhdx_header struct in disk + is only 582 bytes, for purposes of crc + the header is the first 4KB of the 64KB + block */ /* The full header is 4KB, although the actual header data is much smaller. * But for the checksum calculation, it is over the entire 4KB structure, * not just the defined portion of it */ +#define VHDX_HEADER_SIGNATURE 0x64616568 typedef struct QEMU_PACKED VHDXHeader { uint32_t signature; /* "head" in ASCII */ uint32_t checksum; /* CRC-32C hash of the whole header */ @@ -92,7 +99,7 @@ typedef struct QEMU_PACKED VHDXHeader { VHDX file has 2 of these headers, and only the header with the highest sequence number is valid */ - MSGUID file_write_guid; /* 128 bit unique identifier. Must be + MSGUID file_write_guid; /* 128 bit unique identifier. Must be updated to new, unique value before the first modification is made to file */ @@ -114,9 +121,9 @@ typedef struct QEMU_PACKED VHDXHeader { there is no valid log. If non-zero, log entries with this guid are valid. */ - uint16_t log_version; /* version of the log format. Mustn't be - zero, unless log_guid is also zero */ - uint16_t version; /* version of th evhdx file. Currently, + uint16_t log_version; /* version of the log format. Must be + set to zero */ + uint16_t version; /* version of the vhdx file. Currently, only supported version is "1" */ uint32_t log_length; /* length of the log. Must be multiple of 1MB */ @@ -125,6 +132,7 @@ typedef struct QEMU_PACKED VHDXHeader { } VHDXHeader; /* Header for the region table block */ +#define VHDX_REGION_SIGNATURE 0x69676572 /* "regi" in ASCII */ typedef struct QEMU_PACKED VHDXRegionTableHeader { uint32_t signature; /* "regi" in ASCII */ uint32_t checksum; /* CRC-32C hash of the 64KB table */ @@ -151,7 +159,10 @@ typedef struct QEMU_PACKED VHDXRegionTableEntry { /* ---- LOG ENTRY STRUCTURES ---- */ +#define VHDX_LOG_MIN_SIZE (1 * MiB) +#define VHDX_LOG_SECTOR_SIZE (4 * KiB) #define VHDX_LOG_HDR_SIZE 64 +#define VHDX_LOG_SIGNATURE 0x65676f6c typedef struct QEMU_PACKED VHDXLogEntryHeader { uint32_t signature; /* "loge" in ASCII */ uint32_t checksum; /* CRC-32C hash of the 64KB table */ @@ -174,7 +185,8 @@ typedef struct QEMU_PACKED VHDXLogEntryHeader { } VHDXLogEntryHeader; #define VHDX_LOG_DESC_SIZE 32 - +#define VHDX_LOG_DESC_SIGNATURE 0x63736564 +#define VHDX_LOG_ZERO_SIGNATURE 0x6f72657a typedef struct QEMU_PACKED VHDXLogDescriptor { uint32_t signature; /* "zero" or "desc" in ASCII */ union { @@ -194,6 +206,7 @@ typedef struct QEMU_PACKED VHDXLogDescriptor { vhdx_log_entry_header */ } VHDXLogDescriptor; +#define VHDX_LOG_DATA_SIGNATURE 0x61746164 typedef struct QEMU_PACKED VHDXLogDataSector { uint32_t data_signature; /* "data" in ASCII */ uint32_t sequence_high; /* 4 MSB of 8 byte sequence_number */ @@ -211,20 +224,21 @@ typedef struct QEMU_PACKED VHDXLogDataSector { #define PAYLOAD_BLOCK_NOT_PRESENT 0 #define PAYLOAD_BLOCK_UNDEFINED 1 #define PAYLOAD_BLOCK_ZERO 2 -#define PAYLOAD_BLOCK_UNMAPPED 5 -#define PAYLOAD_BLOCK_FULL_PRESENT 6 +#define PAYLOAD_BLOCK_UNMAPPED 3 +#define PAYLOAD_BLOCK_UNMAPPED_v095 5 +#define PAYLOAD_BLOCK_FULLY_PRESENT 6 #define PAYLOAD_BLOCK_PARTIALLY_PRESENT 7 #define SB_BLOCK_NOT_PRESENT 0 #define SB_BLOCK_PRESENT 6 /* per the spec */ -#define VHDX_MAX_SECTORS_PER_BLOCK (1<<23) +#define VHDX_MAX_SECTORS_PER_BLOCK (1 << 23) /* upper 44 bits are the file offset in 1MB units lower 3 bits are the state other bits are reserved */ #define VHDX_BAT_STATE_BIT_MASK 0x07 -#define VHDX_BAT_FILE_OFF_BITS (64-44) +#define VHDX_BAT_FILE_OFF_MASK 0xFFFFFFFFFFF00000ULL /* upper 44 bits */ typedef uint64_t VHDXBatEntry; /* ---- METADATA REGION STRUCTURES ---- */ @@ -233,6 +247,7 @@ typedef uint64_t VHDXBatEntry; #define VHDX_METADATA_MAX_ENTRIES 2047 /* not including the header */ #define VHDX_METADATA_TABLE_MAX_SIZE \ (VHDX_METADATA_ENTRY_SIZE * (VHDX_METADATA_MAX_ENTRIES+1)) +#define VHDX_METADATA_SIGNATURE 0x617461646174656DULL /* "metadata" in ASCII */ typedef struct QEMU_PACKED VHDXMetadataTableHeader { uint64_t signature; /* "metadata" in ASCII */ uint16_t reserved; @@ -252,8 +267,8 @@ typedef struct QEMU_PACKED VHDXMetadataTableEntry { metadata region */ /* note: if length = 0, so is offset */ uint32_t length; /* length of metadata. <= 1MB. */ - uint32_t data_bits; /* least-significant 3 bits are flags, the - rest are reserved (see above) */ + uint32_t data_bits; /* least-significant 3 bits are flags, + the rest are reserved (see above) */ uint32_t reserved2; } VHDXMetadataTableEntry; @@ -262,13 +277,16 @@ typedef struct QEMU_PACKED VHDXMetadataTableEntry { If set indicates a fixed size VHDX file */ #define VHDX_PARAMS_HAS_PARENT 0x02 /* has parent / backing file */ +#define VHDX_BLOCK_SIZE_MIN (1 * MiB) +#define VHDX_BLOCK_SIZE_MAX (256 * MiB) typedef struct QEMU_PACKED VHDXFileParameters { uint32_t block_size; /* size of each payload block, always power of 2, <= 256MB and >= 1MB. */ - uint32_t data_bits; /* least-significant 2 bits are flags, the rest - are reserved (see above) */ + uint32_t data_bits; /* least-significant 2 bits are flags, + the rest are reserved (see above) */ } VHDXFileParameters; +#define VHDX_MAX_IMAGE_SIZE ((uint64_t) 64 * TiB) typedef struct QEMU_PACKED VHDXVirtualDiskSize { uint64_t virtual_disk_size; /* Size of the virtual disk, in bytes. Must be multiple of the sector size, @@ -276,7 +294,7 @@ typedef struct QEMU_PACKED VHDXVirtualDiskSize { } VHDXVirtualDiskSize; typedef struct QEMU_PACKED VHDXPage83Data { - MSGUID page_83_data[16]; /* unique id for scsi devices that + MSGUID page_83_data; /* unique id for scsi devices that support page 0x83 */ } VHDXPage83Data; @@ -291,7 +309,7 @@ typedef struct QEMU_PACKED VHDXVirtualDiskPhysicalSectorSize { } VHDXVirtualDiskPhysicalSectorSize; typedef struct QEMU_PACKED VHDXParentLocatorHeader { - MSGUID locator_type[16]; /* type of the parent virtual disk. */ + MSGUID locator_type; /* type of the parent virtual disk. */ uint16_t reserved; uint16_t key_value_count; /* number of key/value pairs for this locator */ @@ -308,18 +326,126 @@ typedef struct QEMU_PACKED VHDXParentLocatorEntry { /* ----- END VHDX SPECIFICATION STRUCTURES ---- */ +typedef struct VHDXMetadataEntries { + VHDXMetadataTableEntry file_parameters_entry; + VHDXMetadataTableEntry virtual_disk_size_entry; + VHDXMetadataTableEntry page83_data_entry; + VHDXMetadataTableEntry logical_sector_size_entry; + VHDXMetadataTableEntry phys_sector_size_entry; + VHDXMetadataTableEntry parent_locator_entry; + uint16_t present; +} VHDXMetadataEntries; + +typedef struct VHDXLogEntries { + uint64_t offset; + uint64_t length; + uint32_t write; + uint32_t read; + VHDXLogEntryHeader *hdr; + void *desc_buffer; + uint64_t sequence; + uint32_t tail; +} VHDXLogEntries; + +typedef struct VHDXRegionEntry { + uint64_t start; + uint64_t end; + QLIST_ENTRY(VHDXRegionEntry) entries; +} VHDXRegionEntry; + +typedef struct BDRVVHDXState { + CoMutex lock; + + int curr_header; + VHDXHeader *headers[2]; + + VHDXRegionTableHeader rt; + VHDXRegionTableEntry bat_rt; /* region table for the BAT */ + VHDXRegionTableEntry metadata_rt; /* region table for the metadata */ + + VHDXMetadataTableHeader metadata_hdr; + VHDXMetadataEntries metadata_entries; + + VHDXFileParameters params; + uint32_t block_size; + uint32_t block_size_bits; + uint32_t sectors_per_block; + uint32_t sectors_per_block_bits; + + uint64_t virtual_disk_size; + uint32_t logical_sector_size; + uint32_t physical_sector_size; + + uint64_t chunk_ratio; + uint32_t chunk_ratio_bits; + uint32_t logical_sector_size_bits; + + uint32_t bat_entries; + VHDXBatEntry *bat; + uint64_t bat_offset; + bool first_visible_write; + MSGUID session_guid; + + VHDXLogEntries log; + + VHDXParentLocatorHeader parent_header; + VHDXParentLocatorEntry *parent_entries; + + Error *migration_blocker; + + bool log_replayed_on_open; + + QLIST_HEAD(, VHDXRegionEntry) regions; +} BDRVVHDXState; + +void vhdx_guid_generate(MSGUID *guid); + +int vhdx_update_headers(BlockDriverState *bs, BDRVVHDXState *s, bool rw, + MSGUID *log_guid); + +uint32_t vhdx_update_checksum(uint8_t *buf, size_t size, int crc_offset); uint32_t vhdx_checksum_calc(uint32_t crc, uint8_t *buf, size_t size, int crc_offset); bool vhdx_checksum_is_valid(uint8_t *buf, size_t size, int crc_offset); +int vhdx_parse_log(BlockDriverState *bs, BDRVVHDXState *s, bool *flushed, + Error **errp); + +int vhdx_log_write_and_flush(BlockDriverState *bs, BDRVVHDXState *s, + void *data, uint32_t length, uint64_t offset); + +static inline void leguid_to_cpus(MSGUID *guid) +{ + guid->data1 = le32_to_cpu(guid->data1); + guid->data2 = le16_to_cpu(guid->data2); + guid->data3 = le16_to_cpu(guid->data3); +} -static void leguid_to_cpus(MSGUID *guid) +static inline void cpu_to_leguids(MSGUID *guid) { - le32_to_cpus(&guid->data1); - le16_to_cpus(&guid->data2); - le16_to_cpus(&guid->data3); + guid->data1 = cpu_to_le32(guid->data1); + guid->data2 = cpu_to_le16(guid->data2); + guid->data3 = cpu_to_le16(guid->data3); } +void vhdx_header_le_import(VHDXHeader *h); +void vhdx_header_le_export(VHDXHeader *orig_h, VHDXHeader *new_h); +void vhdx_log_desc_le_import(VHDXLogDescriptor *d); +void vhdx_log_desc_le_export(VHDXLogDescriptor *d); +void vhdx_log_data_le_import(VHDXLogDataSector *d); +void vhdx_log_data_le_export(VHDXLogDataSector *d); +void vhdx_log_entry_hdr_le_import(VHDXLogEntryHeader *hdr); +void vhdx_log_entry_hdr_le_export(VHDXLogEntryHeader *hdr); +void vhdx_region_header_le_import(VHDXRegionTableHeader *hdr); +void vhdx_region_header_le_export(VHDXRegionTableHeader *hdr); +void vhdx_region_entry_le_import(VHDXRegionTableEntry *e); +void vhdx_region_entry_le_export(VHDXRegionTableEntry *e); +void vhdx_metadata_header_le_import(VHDXMetadataTableHeader *hdr); +void vhdx_metadata_header_le_export(VHDXMetadataTableHeader *hdr); +void vhdx_metadata_entry_le_import(VHDXMetadataTableEntry *e); +void vhdx_metadata_entry_le_export(VHDXMetadataTableEntry *e); +int vhdx_user_visible_write(BlockDriverState *bs, BDRVVHDXState *s); + #endif |