qemu/block/vhdx-endian.c
Jeff Cody 4f75b52a07 block: VHDX endian fixes
This patch contains several changes for endian conversion fixes for
VHDX, particularly for big-endian machines (multibyte values in VHDX are
all on disk in LE format).

Tests were done with existing qemu-iotests on an IBM POWER7 (8406-71Y).
This includes sample images created by Hyper-V, both with dirty logs and
without.

In addition, VHDX image files created (and written to) on a BE machine
were tested on a LE machine, and vice-versa.

Reported-by: Markus Armburster <armbru@redhat.com>
Reported-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-08-15 15:07:14 +02:00

224 lines
5.3 KiB
C

/*
* 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);
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_import(VHDXLogDataSector *d)
{
assert(d != NULL);
le32_to_cpus(&d->data_signature);
le32_to_cpus(&d->sequence_high);
le32_to_cpus(&d->sequence_low);
}
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);
}
/* Region table entries */
void vhdx_region_header_le_import(VHDXRegionTableHeader *hdr)
{
assert(hdr != NULL);
le32_to_cpus(&hdr->signature);
le32_to_cpus(&hdr->checksum);
le32_to_cpus(&hdr->entry_count);
}
void vhdx_region_header_le_export(VHDXRegionTableHeader *hdr)
{
assert(hdr != NULL);
cpu_to_le32s(&hdr->signature);
cpu_to_le32s(&hdr->checksum);
cpu_to_le32s(&hdr->entry_count);
}
void vhdx_region_entry_le_import(VHDXRegionTableEntry *e)
{
assert(e != NULL);
leguid_to_cpus(&e->guid);
le64_to_cpus(&e->file_offset);
le32_to_cpus(&e->length);
le32_to_cpus(&e->data_bits);
}
void vhdx_region_entry_le_export(VHDXRegionTableEntry *e)
{
assert(e != NULL);
cpu_to_leguids(&e->guid);
cpu_to_le64s(&e->file_offset);
cpu_to_le32s(&e->length);
cpu_to_le32s(&e->data_bits);
}
/* Metadata headers & table */
void vhdx_metadata_header_le_import(VHDXMetadataTableHeader *hdr)
{
assert(hdr != NULL);
le64_to_cpus(&hdr->signature);
le16_to_cpus(&hdr->entry_count);
}
void vhdx_metadata_header_le_export(VHDXMetadataTableHeader *hdr)
{
assert(hdr != NULL);
cpu_to_le64s(&hdr->signature);
cpu_to_le16s(&hdr->entry_count);
}
void vhdx_metadata_entry_le_import(VHDXMetadataTableEntry *e)
{
assert(e != NULL);
leguid_to_cpus(&e->item_id);
le32_to_cpus(&e->offset);
le32_to_cpus(&e->length);
le32_to_cpus(&e->data_bits);
}
void vhdx_metadata_entry_le_export(VHDXMetadataTableEntry *e)
{
assert(e != NULL);
cpu_to_leguids(&e->item_id);
cpu_to_le32s(&e->offset);
cpu_to_le32s(&e->length);
cpu_to_le32s(&e->data_bits);
}