block: vhdx - log support struct and defines

This adds some magic number defines, and internal structure definitions
for VHDX log replay support.  The struct VHDXLogEntries does not reflect
an on-disk data structure, and thus does not need to be packed.

Some minor code style fixes are applied as well.

Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Jeff Cody 2013-10-30 10:44:41 -04:00 committed by Stefan Hajnoczi
parent 28541d4628
commit 625565d27e

View File

@ -30,12 +30,12 @@
* 0.........64KB...........128KB........192KB..........256KB................1MB
*/
#define VHDX_HEADER_BLOCK_SIZE (64*1024)
#define VHDX_HEADER_BLOCK_SIZE (64 * 1024)
#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)
/*
@ -77,7 +77,7 @@ typedef struct QEMU_PACKED 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
#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 */
@ -151,7 +151,10 @@ typedef struct QEMU_PACKED VHDXRegionTableEntry {
/* ---- LOG ENTRY STRUCTURES ---- */
#define VHDX_LOG_MIN_SIZE (1024 * 1024)
#define VHDX_LOG_SECTOR_SIZE 4096
#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 +177,8 @@ 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 +198,7 @@ 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 */
@ -219,12 +224,12 @@ typedef struct QEMU_PACKED VHDXLogDataSector {
#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_BITS (64 - 44)
typedef uint64_t VHDXBatEntry;
/* ---- METADATA REGION STRUCTURES ---- */
@ -252,8 +257,8 @@ 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;
@ -265,8 +270,8 @@ typedef struct QEMU_PACKED VHDXMetadataTableEntry {
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;
typedef struct QEMU_PACKED VHDXVirtualDiskSize {
@ -318,6 +323,13 @@ typedef struct VHDXMetadataEntries {
uint16_t present;
} VHDXMetadataEntries;
typedef struct VHDXLogEntries {
uint64_t offset;
uint64_t length;
uint32_t head;
uint32_t tail;
} VHDXLogEntries;
typedef struct BDRVVHDXState {
CoMutex lock;
@ -351,6 +363,8 @@ typedef struct BDRVVHDXState {
MSGUID session_guid;
VHDXLogEntries log;
VHDXParentLocatorHeader parent_header;
VHDXParentLocatorEntry *parent_entries;