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block: vhdx - break endian translation functions out
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This moves the endian translation functions out from the vhdx.c source,
into a separate source file. In addition to the previously defined
endian functions, new endian translation functions for log support are
added as well.

Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
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codyprime authored and stefanhaRH committed Nov 7, 2013
1 parent 625565d commit 0f48e8f
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Showing 4 changed files with 150 additions and 44 deletions.
2 changes: 1 addition & 1 deletion block/Makefile.objs
Expand Up @@ -2,7 +2,7 @@ block-obj-y += raw_bsd.o cow.o qcow.o vdi.o vmdk.o cloop.o dmg.o bochs.o vpc.o v
block-obj-y += qcow2.o qcow2-refcount.o qcow2-cluster.o qcow2-snapshot.o qcow2-cache.o
block-obj-y += qed.o qed-gencb.o qed-l2-cache.o qed-table.o qed-cluster.o
block-obj-y += qed-check.o
block-obj-$(CONFIG_VHDX) += vhdx.o
block-obj-$(CONFIG_VHDX) += vhdx.o vhdx-endian.o
block-obj-y += parallels.o blkdebug.o blkverify.o
block-obj-y += snapshot.o qapi.o
block-obj-$(CONFIG_WIN32) += raw-win32.o win32-aio.o
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141 changes: 141 additions & 0 deletions block/vhdx-endian.c
@@ -0,0 +1,141 @@
/*
* 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 "block/vhdx.h"

#include <uuid/uuid.h>


/*
* All the VHDX formats on disk are little endian - the following
* are helper import/export functions to correctly convert
* endianness from disk read to native cpu format, and back again.
*/


/* VHDX File Header */


void vhdx_header_le_import(VHDXHeader *h)
{
assert(h != NULL);

le32_to_cpus(&h->signature);
le32_to_cpus(&h->checksum);
le64_to_cpus(&h->sequence_number);

leguid_to_cpus(&h->file_write_guid);
leguid_to_cpus(&h->data_write_guid);
leguid_to_cpus(&h->log_guid);

le16_to_cpus(&h->log_version);
le16_to_cpus(&h->version);
le32_to_cpus(&h->log_length);
le64_to_cpus(&h->log_offset);
}

void vhdx_header_le_export(VHDXHeader *orig_h, VHDXHeader *new_h)
{
assert(orig_h != NULL);
assert(new_h != NULL);

new_h->signature = cpu_to_le32(orig_h->signature);
new_h->checksum = cpu_to_le32(orig_h->checksum);
new_h->sequence_number = cpu_to_le64(orig_h->sequence_number);

new_h->file_write_guid = orig_h->file_write_guid;
new_h->data_write_guid = orig_h->data_write_guid;
new_h->log_guid = orig_h->log_guid;

cpu_to_leguids(&new_h->file_write_guid);
cpu_to_leguids(&new_h->data_write_guid);
cpu_to_leguids(&new_h->log_guid);

new_h->log_version = cpu_to_le16(orig_h->log_version);
new_h->version = cpu_to_le16(orig_h->version);
new_h->log_length = cpu_to_le32(orig_h->log_length);
new_h->log_offset = cpu_to_le64(orig_h->log_offset);
}


/* VHDX Log Headers */


void vhdx_log_desc_le_import(VHDXLogDescriptor *d)
{
assert(d != NULL);

le32_to_cpus(&d->signature);
le32_to_cpus(&d->trailing_bytes);
le64_to_cpus(&d->leading_bytes);
le64_to_cpus(&d->file_offset);
le64_to_cpus(&d->sequence_number);
}

void vhdx_log_desc_le_export(VHDXLogDescriptor *d)
{
assert(d != NULL);

cpu_to_le32s(&d->signature);
cpu_to_le32s(&d->trailing_bytes);
cpu_to_le64s(&d->leading_bytes);
cpu_to_le64s(&d->file_offset);
cpu_to_le64s(&d->sequence_number);
}

void vhdx_log_data_le_export(VHDXLogDataSector *d)
{
assert(d != NULL);

cpu_to_le32s(&d->data_signature);
cpu_to_le32s(&d->sequence_high);
cpu_to_le32s(&d->sequence_low);
}

void vhdx_log_entry_hdr_le_import(VHDXLogEntryHeader *hdr)
{
assert(hdr != NULL);

le32_to_cpus(&hdr->signature);
le32_to_cpus(&hdr->checksum);
le32_to_cpus(&hdr->entry_length);
le32_to_cpus(&hdr->tail);
le64_to_cpus(&hdr->sequence_number);
le32_to_cpus(&hdr->descriptor_count);
leguid_to_cpus(&hdr->log_guid);
le64_to_cpus(&hdr->flushed_file_offset);
le64_to_cpus(&hdr->last_file_offset);
}

void vhdx_log_entry_hdr_le_export(VHDXLogEntryHeader *hdr)
{
assert(hdr != NULL);

cpu_to_le32s(&hdr->signature);
cpu_to_le32s(&hdr->checksum);
cpu_to_le32s(&hdr->entry_length);
cpu_to_le32s(&hdr->tail);
cpu_to_le64s(&hdr->sequence_number);
cpu_to_le32s(&hdr->descriptor_count);
cpu_to_leguids(&hdr->log_guid);
cpu_to_le64s(&hdr->flushed_file_offset);
cpu_to_le64s(&hdr->last_file_offset);
}


43 changes: 0 additions & 43 deletions block/vhdx.c
Expand Up @@ -223,49 +223,6 @@ static int vhdx_probe(const uint8_t *buf, int buf_size, const char *filename)
return 0;
}

/* All VHDX structures on disk are little endian */
static void vhdx_header_le_import(VHDXHeader *h)
{
assert(h != NULL);

le32_to_cpus(&h->signature);
le32_to_cpus(&h->checksum);
le64_to_cpus(&h->sequence_number);

leguid_to_cpus(&h->file_write_guid);
leguid_to_cpus(&h->data_write_guid);
leguid_to_cpus(&h->log_guid);

le16_to_cpus(&h->log_version);
le16_to_cpus(&h->version);
le32_to_cpus(&h->log_length);
le64_to_cpus(&h->log_offset);
}

/* All VHDX structures on disk are little endian */
static void vhdx_header_le_export(VHDXHeader *orig_h, VHDXHeader *new_h)
{
assert(orig_h != NULL);
assert(new_h != NULL);

new_h->signature = cpu_to_le32(orig_h->signature);
new_h->checksum = cpu_to_le32(orig_h->checksum);
new_h->sequence_number = cpu_to_le64(orig_h->sequence_number);

new_h->file_write_guid = orig_h->file_write_guid;
new_h->data_write_guid = orig_h->data_write_guid;
new_h->log_guid = orig_h->log_guid;

cpu_to_leguids(&new_h->file_write_guid);
cpu_to_leguids(&new_h->data_write_guid);
cpu_to_leguids(&new_h->log_guid);

new_h->log_version = cpu_to_le16(orig_h->log_version);
new_h->version = cpu_to_le16(orig_h->version);
new_h->log_length = cpu_to_le32(orig_h->log_length);
new_h->log_offset = cpu_to_le64(orig_h->log_offset);
}

/* Update the VHDX headers
*
* This follows the VHDX spec procedures for header updates.
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8 changes: 8 additions & 0 deletions block/vhdx.h
Expand Up @@ -394,4 +394,12 @@ static inline void cpu_to_leguids(MSGUID *guid)
cpu_to_le16s(&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_export(VHDXLogDataSector *d);
void vhdx_log_entry_hdr_le_import(VHDXLogEntryHeader *hdr);
void vhdx_log_entry_hdr_le_export(VHDXLogEntryHeader *hdr);

#endif

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