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