From a60094cdc27c9913ad93fc42383161ed40015e44 Mon Sep 17 00:00:00 2001

From: Jeffrey Cody <jcody@redhat.com>

Date: Wed, 20 Nov 2013 19:43:53 +0100

Subject: [PATCH 10/25] block: vhdx - log support struct and defines

RH-Author: Jeffrey Cody <jcody@redhat.com>

Message-id: <2dae7f05c8661b506f3bbaa60cd8b3ad35d7a7e4.1384975172.git.jcody@redhat.com>

Patchwork-id: 55803

O-Subject: [RHEL7 qemu-kvm PATCH 10/26] block: vhdx - log support struct and defines

Bugzilla: 879234

RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>

RH-Acked-by: Paolo Bonzini <pbonzini@redhat.com>

RH-Acked-by: Fam Zheng <famz@redhat.com>

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>

(cherry picked from commit 625565d27e8d7c7f7238ccd118a2cd49c1c52963)

---

 block/vhdx.h | 46 ++++++++++++++++++++++++++++++----------------

 1 file changed, 30 insertions(+), 16 deletions(-)

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>

---

 block/vhdx.h |   46 ++++++++++++++++++++++++++++++----------------

 1 files changed, 30 insertions(+), 16 deletions(-)

diff --git a/block/vhdx.h b/block/vhdx.h

index 57375ff..76ce4aa 100644

--- a/block/vhdx.h

+++ b/block/vhdx.h

@@ -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)

 /*

@@ -77,10 +77,10 @@ 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

-                                       is only 582 bytes, for purposes of crc

-                                       the header is the first 4KB of the 64KB

-                                       block */

+#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 */

 /* 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,

@@ -92,7 +92,7 @@ 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 */

@@ -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;

-- 

1.7.1