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     le32_to_cpus(&d->trailing_bytes);
  86     le64_to_cpus(&d->leading_bytes);
  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_export(VHDXLogDataSector *d)
 103 {
 104     assert(d != NULL);
 105
 106     cpu_to_le32s(&d->data_signature);
 107     cpu_to_le32s(&d->sequence_high);
 108     cpu_to_le32s(&d->sequence_low);
 109 }
 110
 111 void vhdx_log_entry_hdr_le_import(VHDXLogEntryHeader *hdr)
 112 {
 113     assert(hdr != NULL);
 114
 115     le32_to_cpus(&hdr->signature);
 116     le32_to_cpus(&hdr->checksum);
 117     le32_to_cpus(&hdr->entry_length);
 118     le32_to_cpus(&hdr->tail);
 119     le64_to_cpus(&hdr->sequence_number);
 120     le32_to_cpus(&hdr->descriptor_count);
 121     leguid_to_cpus(&hdr->log_guid);
 122     le64_to_cpus(&hdr->flushed_file_offset);
 123     le64_to_cpus(&hdr->last_file_offset);
 124 }
 125
 126 void vhdx_log_entry_hdr_le_export(VHDXLogEntryHeader *hdr)
 127 {
 128     assert(hdr != NULL);
 129
 130     cpu_to_le32s(&hdr->signature);
 131     cpu_to_le32s(&hdr->checksum);
 132     cpu_to_le32s(&hdr->entry_length);
 133     cpu_to_le32s(&hdr->tail);
 134     cpu_to_le64s(&hdr->sequence_number);
 135     cpu_to_le32s(&hdr->descriptor_count);
 136     cpu_to_leguids(&hdr->log_guid);
 137     cpu_to_le64s(&hdr->flushed_file_offset);
 138     cpu_to_le64s(&hdr->last_file_offset);
 139 }
 140
 141
 142 /* Region table entries */
 143 void vhdx_region_header_le_import(VHDXRegionTableHeader *hdr)
 144 {
 145     assert(hdr != NULL);
 146
 147     le32_to_cpus(&hdr->signature);
 148     le32_to_cpus(&hdr->checksum);
 149     le32_to_cpus(&hdr->entry_count);
 150 }
 151
 152 void vhdx_region_header_le_export(VHDXRegionTableHeader *hdr)
 153 {
 154     assert(hdr != NULL);
 155
 156     cpu_to_le32s(&hdr->signature);
 157     cpu_to_le32s(&hdr->checksum);
 158     cpu_to_le32s(&hdr->entry_count);
 159 }
 160
 161 void vhdx_region_entry_le_import(VHDXRegionTableEntry *e)
 162 {
 163     assert(e != NULL);
 164
 165     leguid_to_cpus(&e->guid);
 166     le64_to_cpus(&e->file_offset);
 167     le32_to_cpus(&e->length);
 168     le32_to_cpus(&e->data_bits);
 169 }
 170
 171 void vhdx_region_entry_le_export(VHDXRegionTableEntry *e)
 172 {
 173     assert(e != NULL);
 174
 175     cpu_to_leguids(&e->guid);
 176     cpu_to_le64s(&e->file_offset);
 177     cpu_to_le32s(&e->length);
 178     cpu_to_le32s(&e->data_bits);
 179 }
 180
 181
 182 /* Metadata headers & table */
 183 void vhdx_metadata_header_le_import(VHDXMetadataTableHeader *hdr)
 184 {
 185     assert(hdr != NULL);
 186
 187     le64_to_cpus(&hdr->signature);
 188     le16_to_cpus(&hdr->entry_count);
 189 }
 190
 191 void vhdx_metadata_header_le_export(VHDXMetadataTableHeader *hdr)
 192 {
 193     assert(hdr != NULL);
 194
 195     cpu_to_le64s(&hdr->signature);
 196     cpu_to_le16s(&hdr->entry_count);
 197 }
 198
 199 void vhdx_metadata_entry_le_import(VHDXMetadataTableEntry *e)
 200 {
 201     assert(e != NULL);
 202
 203     leguid_to_cpus(&e->item_id);
 204     le32_to_cpus(&e->offset);
 205     le32_to_cpus(&e->length);
 206     le32_to_cpus(&e->data_bits);
 207 }
 208 void vhdx_metadata_entry_le_export(VHDXMetadataTableEntry *e)
 209 {
 210     assert(e != NULL);
 211
 212     cpu_to_leguids(&e->item_id);
 213     cpu_to_le32s(&e->offset);
 214     cpu_to_le32s(&e->length);
 215     cpu_to_le32s(&e->data_bits);
 216 }