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 "block/vhdx.h"
  22
  23 #include <uuid/uuid.h>
  24
  25
  26 /*
  27  * All the VHDX formats on disk are little endian - the following
  28  * are helper import/export functions to correctly convert
  29  * endianness from disk read to native cpu format, and back again.
  30  */
  31
  32
  33 /* VHDX File Header */
  34
  35
  36 void vhdx_header_le_import(VHDXHeader *h)
  37 {
  38     assert(h != NULL);
  39
  40     le32_to_cpus(&h->signature);
  41     le32_to_cpus(&h->checksum);
  42     le64_to_cpus(&h->sequence_number);
  43
  44     leguid_to_cpus(&h->file_write_guid);
  45     leguid_to_cpus(&h->data_write_guid);
  46     leguid_to_cpus(&h->log_guid);
  47
  48     le16_to_cpus(&h->log_version);
  49     le16_to_cpus(&h->version);
  50     le32_to_cpus(&h->log_length);
  51     le64_to_cpus(&h->log_offset);
  52 }
  53
  54 void vhdx_header_le_export(VHDXHeader *orig_h, VHDXHeader *new_h)
  55 {
  56     assert(orig_h != NULL);
  57     assert(new_h != NULL);
  58
  59     new_h->signature       = cpu_to_le32(orig_h->signature);
  60     new_h->checksum        = cpu_to_le32(orig_h->checksum);
  61     new_h->sequence_number = cpu_to_le64(orig_h->sequence_number);
  62
  63     new_h->file_write_guid = orig_h->file_write_guid;
  64     new_h->data_write_guid = orig_h->data_write_guid;
  65     new_h->log_guid        = orig_h->log_guid;
  66
  67     cpu_to_leguids(&new_h->file_write_guid);
  68     cpu_to_leguids(&new_h->data_write_guid);
  69     cpu_to_leguids(&new_h->log_guid);
  70
  71     new_h->log_version     = cpu_to_le16(orig_h->log_version);
  72     new_h->version         = cpu_to_le16(orig_h->version);
  73     new_h->log_length      = cpu_to_le32(orig_h->log_length);
  74     new_h->log_offset      = cpu_to_le64(orig_h->log_offset);
  75 }
  76
  77
  78 /* VHDX Log Headers */
  79
  80
  81 void vhdx_log_desc_le_import(VHDXLogDescriptor *d)
  82 {
  83     assert(d != NULL);
  84
  85     le32_to_cpus(&d->signature);
  86     le64_to_cpus(&d->file_offset);
  87     le64_to_cpus(&d->sequence_number);
  88 }
  89
  90 void vhdx_log_desc_le_export(VHDXLogDescriptor *d)
  91 {
  92     assert(d != NULL);
  93
  94     cpu_to_le32s(&d->signature);
  95     cpu_to_le32s(&d->trailing_bytes);
  96     cpu_to_le64s(&d->leading_bytes);
  97     cpu_to_le64s(&d->file_offset);
  98     cpu_to_le64s(&d->sequence_number);
  99 }
 100
 101 void vhdx_log_data_le_import(VHDXLogDataSector *d)
 102 {
 103     assert(d != NULL);
 104
 105     le32_to_cpus(&d->data_signature);
 106     le32_to_cpus(&d->sequence_high);
 107     le32_to_cpus(&d->sequence_low);
 108 }
 109
 110 void vhdx_log_data_le_export(VHDXLogDataSector *d)
 111 {
 112     assert(d != NULL);
 113
 114     cpu_to_le32s(&d->data_signature);
 115     cpu_to_le32s(&d->sequence_high);
 116     cpu_to_le32s(&d->sequence_low);
 117 }
 118
 119 void vhdx_log_entry_hdr_le_import(VHDXLogEntryHeader *hdr)
 120 {
 121     assert(hdr != NULL);
 122
 123     le32_to_cpus(&hdr->signature);
 124     le32_to_cpus(&hdr->checksum);
 125     le32_to_cpus(&hdr->entry_length);
 126     le32_to_cpus(&hdr->tail);
 127     le64_to_cpus(&hdr->sequence_number);
 128     le32_to_cpus(&hdr->descriptor_count);
 129     leguid_to_cpus(&hdr->log_guid);
 130     le64_to_cpus(&hdr->flushed_file_offset);
 131     le64_to_cpus(&hdr->last_file_offset);
 132 }
 133
 134 void vhdx_log_entry_hdr_le_export(VHDXLogEntryHeader *hdr)
 135 {
 136     assert(hdr != NULL);
 137
 138     cpu_to_le32s(&hdr->signature);
 139     cpu_to_le32s(&hdr->checksum);
 140     cpu_to_le32s(&hdr->entry_length);
 141     cpu_to_le32s(&hdr->tail);
 142     cpu_to_le64s(&hdr->sequence_number);
 143     cpu_to_le32s(&hdr->descriptor_count);
 144     cpu_to_leguids(&hdr->log_guid);
 145     cpu_to_le64s(&hdr->flushed_file_offset);
 146     cpu_to_le64s(&hdr->last_file_offset);
 147 }
 148
 149
 150 /* Region table entries */
 151 void vhdx_region_header_le_import(VHDXRegionTableHeader *hdr)
 152 {
 153     assert(hdr != NULL);
 154
 155     le32_to_cpus(&hdr->signature);
 156     le32_to_cpus(&hdr->checksum);
 157     le32_to_cpus(&hdr->entry_count);
 158 }
 159
 160 void vhdx_region_header_le_export(VHDXRegionTableHeader *hdr)
 161 {
 162     assert(hdr != NULL);
 163
 164     cpu_to_le32s(&hdr->signature);
 165     cpu_to_le32s(&hdr->checksum);
 166     cpu_to_le32s(&hdr->entry_count);
 167 }
 168
 169 void vhdx_region_entry_le_import(VHDXRegionTableEntry *e)
 170 {
 171     assert(e != NULL);
 172
 173     leguid_to_cpus(&e->guid);
 174     le64_to_cpus(&e->file_offset);
 175     le32_to_cpus(&e->length);
 176     le32_to_cpus(&e->data_bits);
 177 }
 178
 179 void vhdx_region_entry_le_export(VHDXRegionTableEntry *e)
 180 {
 181     assert(e != NULL);
 182
 183     cpu_to_leguids(&e->guid);
 184     cpu_to_le64s(&e->file_offset);
 185     cpu_to_le32s(&e->length);
 186     cpu_to_le32s(&e->data_bits);
 187 }
 188
 189
 190 /* Metadata headers & table */
 191 void vhdx_metadata_header_le_import(VHDXMetadataTableHeader *hdr)
 192 {
 193     assert(hdr != NULL);
 194
 195     le64_to_cpus(&hdr->signature);
 196     le16_to_cpus(&hdr->entry_count);
 197 }
 198
 199 void vhdx_metadata_header_le_export(VHDXMetadataTableHeader *hdr)
 200 {
 201     assert(hdr != NULL);
 202
 203     cpu_to_le64s(&hdr->signature);
 204     cpu_to_le16s(&hdr->entry_count);
 205 }
 206
 207 void vhdx_metadata_entry_le_import(VHDXMetadataTableEntry *e)
 208 {
 209     assert(e != NULL);
 210
 211     leguid_to_cpus(&e->item_id);
 212     le32_to_cpus(&e->offset);
 213     le32_to_cpus(&e->length);
 214     le32_to_cpus(&e->data_bits);
 215 }
 216 void vhdx_metadata_entry_le_export(VHDXMetadataTableEntry *e)
 217 {
 218     assert(e != NULL);
 219
 220     cpu_to_leguids(&e->item_id);
 221     cpu_to_le32s(&e->offset);
 222     cpu_to_le32s(&e->length);
 223     cpu_to_le32s(&e->data_bits);
 224 }