block/vhdx-endian.c

   1 /*
   2  * Block driver for Hyper-V VHDX Images
   3  *
   4  * Copyright (c) 2013 Red Hat, Inc.,
   5  *
   6  * Authors:
   7  *  Jeff Cody <jcody@redhat.com>
   8  *
   9  *  This is based on the "VHDX Format Specification v1.00", published 8/25/2012
  10  *  by Microsoft:
  11  *      https://www.microsoft.com/en-us/download/details.aspx?id=34750
  12  *
  13  * This work is licensed under the terms of the GNU LGPL, version 2 or later.
  14  * See the COPYING.LIB file in the top-level directory.
  15  *
  16  */
  17
  18 #include "qemu/osdep.h"
  19 #include "qemu-common.h"
  20 #include "block/block_int.h"
  21 #include "qemu/bswap.h"
  22 #include "block/vhdx.h"
  23
  24 #include <uuid/uuid.h>
  25
  26
  27 /*
  28  * All the VHDX formats on disk are little endian - the following
  29  * are helper import/export functions to correctly convert
  30  * endianness from disk read to native cpu format, and back again.
  31  */
  32
  33
  34 /* VHDX File Header */
  35
  36
  37 void vhdx_header_le_import(VHDXHeader *h)
  38 {
  39     assert(h != NULL);
  40
  41     le32_to_cpus(&h->signature);
  42     le32_to_cpus(&h->checksum);
  43     le64_to_cpus(&h->sequence_number);
  44
  45     leguid_to_cpus(&h->file_write_guid);
  46     leguid_to_cpus(&h->data_write_guid);
  47     leguid_to_cpus(&h->log_guid);
  48
  49     le16_to_cpus(&h->log_version);
  50     le16_to_cpus(&h->version);
  51     le32_to_cpus(&h->log_length);
  52     le64_to_cpus(&h->log_offset);
  53 }
  54
  55 void vhdx_header_le_export(VHDXHeader *orig_h, VHDXHeader *new_h)
  56 {
  57     assert(orig_h != NULL);
  58     assert(new_h != NULL);
  59
  60     new_h->signature       = cpu_to_le32(orig_h->signature);
  61     new_h->checksum        = cpu_to_le32(orig_h->checksum);
  62     new_h->sequence_number = cpu_to_le64(orig_h->sequence_number);
  63
  64     new_h->file_write_guid = orig_h->file_write_guid;
  65     new_h->data_write_guid = orig_h->data_write_guid;
  66     new_h->log_guid        = orig_h->log_guid;
  67
  68     cpu_to_leguids(&new_h->file_write_guid);
  69     cpu_to_leguids(&new_h->data_write_guid);
  70     cpu_to_leguids(&new_h->log_guid);
  71
  72     new_h->log_version     = cpu_to_le16(orig_h->log_version);
  73     new_h->version         = cpu_to_le16(orig_h->version);
  74     new_h->log_length      = cpu_to_le32(orig_h->log_length);
  75     new_h->log_offset      = cpu_to_le64(orig_h->log_offset);
  76 }
  77
  78
  79 /* VHDX Log Headers */
  80
  81
  82 void vhdx_log_desc_le_import(VHDXLogDescriptor *d)
  83 {
  84     assert(d != NULL);
  85
  86     le32_to_cpus(&d->signature);
  87     le64_to_cpus(&d->file_offset);
  88     le64_to_cpus(&d->sequence_number);
  89 }
  90
  91 void vhdx_log_desc_le_export(VHDXLogDescriptor *d)
  92 {
  93     assert(d != NULL);
  94
  95     cpu_to_le32s(&d->signature);
  96     cpu_to_le32s(&d->trailing_bytes);
  97     cpu_to_le64s(&d->leading_bytes);
  98     cpu_to_le64s(&d->file_offset);
  99     cpu_to_le64s(&d->sequence_number);
 100 }
 101
 102 void vhdx_log_data_le_import(VHDXLogDataSector *d)
 103 {
 104     assert(d != NULL);
 105
 106     le32_to_cpus(&d->data_signature);
 107     le32_to_cpus(&d->sequence_high);
 108     le32_to_cpus(&d->sequence_low);
 109 }
 110
 111 void vhdx_log_data_le_export(VHDXLogDataSector *d)
 112 {
 113     assert(d != NULL);
 114
 115     cpu_to_le32s(&d->data_signature);
 116     cpu_to_le32s(&d->sequence_high);
 117     cpu_to_le32s(&d->sequence_low);
 118 }
 119
 120 void vhdx_log_entry_hdr_le_import(VHDXLogEntryHeader *hdr)
 121 {
 122     assert(hdr != NULL);
 123
 124     le32_to_cpus(&hdr->signature);
 125     le32_to_cpus(&hdr->checksum);
 126     le32_to_cpus(&hdr->entry_length);
 127     le32_to_cpus(&hdr->tail);
 128     le64_to_cpus(&hdr->sequence_number);
 129     le32_to_cpus(&hdr->descriptor_count);
 130     leguid_to_cpus(&hdr->log_guid);
 131     le64_to_cpus(&hdr->flushed_file_offset);
 132     le64_to_cpus(&hdr->last_file_offset);
 133 }
 134
 135 void vhdx_log_entry_hdr_le_export(VHDXLogEntryHeader *hdr)
 136 {
 137     assert(hdr != NULL);
 138
 139     cpu_to_le32s(&hdr->signature);
 140     cpu_to_le32s(&hdr->checksum);
 141     cpu_to_le32s(&hdr->entry_length);
 142     cpu_to_le32s(&hdr->tail);
 143     cpu_to_le64s(&hdr->sequence_number);
 144     cpu_to_le32s(&hdr->descriptor_count);
 145     cpu_to_leguids(&hdr->log_guid);
 146     cpu_to_le64s(&hdr->flushed_file_offset);
 147     cpu_to_le64s(&hdr->last_file_offset);
 148 }
 149
 150
 151 /* Region table entries */
 152 void vhdx_region_header_le_import(VHDXRegionTableHeader *hdr)
 153 {
 154     assert(hdr != NULL);
 155
 156     le32_to_cpus(&hdr->signature);
 157     le32_to_cpus(&hdr->checksum);
 158     le32_to_cpus(&hdr->entry_count);
 159 }
 160
 161 void vhdx_region_header_le_export(VHDXRegionTableHeader *hdr)
 162 {
 163     assert(hdr != NULL);
 164
 165     cpu_to_le32s(&hdr->signature);
 166     cpu_to_le32s(&hdr->checksum);
 167     cpu_to_le32s(&hdr->entry_count);
 168 }
 169
 170 void vhdx_region_entry_le_import(VHDXRegionTableEntry *e)
 171 {
 172     assert(e != NULL);
 173
 174     leguid_to_cpus(&e->guid);
 175     le64_to_cpus(&e->file_offset);
 176     le32_to_cpus(&e->length);
 177     le32_to_cpus(&e->data_bits);
 178 }
 179
 180 void vhdx_region_entry_le_export(VHDXRegionTableEntry *e)
 181 {
 182     assert(e != NULL);
 183
 184     cpu_to_leguids(&e->guid);
 185     cpu_to_le64s(&e->file_offset);
 186     cpu_to_le32s(&e->length);
 187     cpu_to_le32s(&e->data_bits);
 188 }
 189
 190
 191 /* Metadata headers & table */
 192 void vhdx_metadata_header_le_import(VHDXMetadataTableHeader *hdr)
 193 {
 194     assert(hdr != NULL);
 195
 196     le64_to_cpus(&hdr->signature);
 197     le16_to_cpus(&hdr->entry_count);
 198 }
 199
 200 void vhdx_metadata_header_le_export(VHDXMetadataTableHeader *hdr)
 201 {
 202     assert(hdr != NULL);
 203
 204     cpu_to_le64s(&hdr->signature);
 205     cpu_to_le16s(&hdr->entry_count);
 206 }
 207
 208 void vhdx_metadata_entry_le_import(VHDXMetadataTableEntry *e)
 209 {
 210     assert(e != NULL);
 211
 212     leguid_to_cpus(&e->item_id);
 213     le32_to_cpus(&e->offset);
 214     le32_to_cpus(&e->length);
 215     le32_to_cpus(&e->data_bits);
 216 }
 217 void vhdx_metadata_entry_le_export(VHDXMetadataTableEntry *e)
 218 {
 219     assert(e != NULL);
 220
 221     cpu_to_leguids(&e->item_id);
 222     cpu_to_le32s(&e->offset);
 223     cpu_to_le32s(&e->length);
 224     cpu_to_le32s(&e->data_bits);
 225 }