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