xref: /qemu/block/vhdx-endian.c (revision a8d25326)
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 "block/block_int.h"
20 #include "qemu/bswap.h"
21 #include "vhdx.h"
22 
23 /*
24  * All the VHDX formats on disk are little endian - the following
25  * are helper import/export functions to correctly convert
26  * endianness from disk read to native cpu format, and back again.
27  */
28 
29 
30 /* VHDX File Header */
31 
32 
vhdx_header_le_import(VHDXHeader * h)33 void vhdx_header_le_import(VHDXHeader *h)
34 {
35     assert(h != NULL);
36 
37     h->signature = le32_to_cpu(h->signature);
38     h->checksum = le32_to_cpu(h->checksum);
39     h->sequence_number = le64_to_cpu(h->sequence_number);
40 
41     leguid_to_cpus(&h->file_write_guid);
42     leguid_to_cpus(&h->data_write_guid);
43     leguid_to_cpus(&h->log_guid);
44 
45     h->log_version = le16_to_cpu(h->log_version);
46     h->version = le16_to_cpu(h->version);
47     h->log_length = le32_to_cpu(h->log_length);
48     h->log_offset = le64_to_cpu(h->log_offset);
49 }
50 
vhdx_header_le_export(VHDXHeader * orig_h,VHDXHeader * new_h)51 void vhdx_header_le_export(VHDXHeader *orig_h, VHDXHeader *new_h)
52 {
53     assert(orig_h != NULL);
54     assert(new_h != NULL);
55 
56     new_h->signature       = cpu_to_le32(orig_h->signature);
57     new_h->checksum        = cpu_to_le32(orig_h->checksum);
58     new_h->sequence_number = cpu_to_le64(orig_h->sequence_number);
59 
60     new_h->file_write_guid = orig_h->file_write_guid;
61     new_h->data_write_guid = orig_h->data_write_guid;
62     new_h->log_guid        = orig_h->log_guid;
63 
64     cpu_to_leguids(&new_h->file_write_guid);
65     cpu_to_leguids(&new_h->data_write_guid);
66     cpu_to_leguids(&new_h->log_guid);
67 
68     new_h->log_version     = cpu_to_le16(orig_h->log_version);
69     new_h->version         = cpu_to_le16(orig_h->version);
70     new_h->log_length      = cpu_to_le32(orig_h->log_length);
71     new_h->log_offset      = cpu_to_le64(orig_h->log_offset);
72 }
73 
74 
75 /* VHDX Log Headers */
76 
77 
vhdx_log_desc_le_import(VHDXLogDescriptor * d)78 void vhdx_log_desc_le_import(VHDXLogDescriptor *d)
79 {
80     assert(d != NULL);
81 
82     d->signature = le32_to_cpu(d->signature);
83     d->file_offset = le64_to_cpu(d->file_offset);
84     d->sequence_number = le64_to_cpu(d->sequence_number);
85 }
86 
vhdx_log_desc_le_export(VHDXLogDescriptor * d)87 void vhdx_log_desc_le_export(VHDXLogDescriptor *d)
88 {
89     assert(d != NULL);
90 
91     d->signature = cpu_to_le32(d->signature);
92     d->trailing_bytes = cpu_to_le32(d->trailing_bytes);
93     d->leading_bytes = cpu_to_le64(d->leading_bytes);
94     d->file_offset = cpu_to_le64(d->file_offset);
95     d->sequence_number = cpu_to_le64(d->sequence_number);
96 }
97 
vhdx_log_data_le_import(VHDXLogDataSector * d)98 void vhdx_log_data_le_import(VHDXLogDataSector *d)
99 {
100     assert(d != NULL);
101 
102     d->data_signature = le32_to_cpu(d->data_signature);
103     d->sequence_high = le32_to_cpu(d->sequence_high);
104     d->sequence_low = le32_to_cpu(d->sequence_low);
105 }
106 
vhdx_log_data_le_export(VHDXLogDataSector * d)107 void vhdx_log_data_le_export(VHDXLogDataSector *d)
108 {
109     assert(d != NULL);
110 
111     d->data_signature = cpu_to_le32(d->data_signature);
112     d->sequence_high = cpu_to_le32(d->sequence_high);
113     d->sequence_low = cpu_to_le32(d->sequence_low);
114 }
115 
vhdx_log_entry_hdr_le_import(VHDXLogEntryHeader * hdr)116 void vhdx_log_entry_hdr_le_import(VHDXLogEntryHeader *hdr)
117 {
118     assert(hdr != NULL);
119 
120     hdr->signature = le32_to_cpu(hdr->signature);
121     hdr->checksum = le32_to_cpu(hdr->checksum);
122     hdr->entry_length = le32_to_cpu(hdr->entry_length);
123     hdr->tail = le32_to_cpu(hdr->tail);
124     hdr->sequence_number = le64_to_cpu(hdr->sequence_number);
125     hdr->descriptor_count = le32_to_cpu(hdr->descriptor_count);
126     leguid_to_cpus(&hdr->log_guid);
127     hdr->flushed_file_offset = le64_to_cpu(hdr->flushed_file_offset);
128     hdr->last_file_offset = le64_to_cpu(hdr->last_file_offset);
129 }
130 
vhdx_log_entry_hdr_le_export(VHDXLogEntryHeader * hdr)131 void vhdx_log_entry_hdr_le_export(VHDXLogEntryHeader *hdr)
132 {
133     assert(hdr != NULL);
134 
135     hdr->signature = cpu_to_le32(hdr->signature);
136     hdr->checksum = cpu_to_le32(hdr->checksum);
137     hdr->entry_length = cpu_to_le32(hdr->entry_length);
138     hdr->tail = cpu_to_le32(hdr->tail);
139     hdr->sequence_number = cpu_to_le64(hdr->sequence_number);
140     hdr->descriptor_count = cpu_to_le32(hdr->descriptor_count);
141     cpu_to_leguids(&hdr->log_guid);
142     hdr->flushed_file_offset = cpu_to_le64(hdr->flushed_file_offset);
143     hdr->last_file_offset = cpu_to_le64(hdr->last_file_offset);
144 }
145 
146 
147 /* Region table entries */
vhdx_region_header_le_import(VHDXRegionTableHeader * hdr)148 void vhdx_region_header_le_import(VHDXRegionTableHeader *hdr)
149 {
150     assert(hdr != NULL);
151 
152     hdr->signature = le32_to_cpu(hdr->signature);
153     hdr->checksum = le32_to_cpu(hdr->checksum);
154     hdr->entry_count = le32_to_cpu(hdr->entry_count);
155 }
156 
vhdx_region_header_le_export(VHDXRegionTableHeader * hdr)157 void vhdx_region_header_le_export(VHDXRegionTableHeader *hdr)
158 {
159     assert(hdr != NULL);
160 
161     hdr->signature = cpu_to_le32(hdr->signature);
162     hdr->checksum = cpu_to_le32(hdr->checksum);
163     hdr->entry_count = cpu_to_le32(hdr->entry_count);
164 }
165 
vhdx_region_entry_le_import(VHDXRegionTableEntry * e)166 void vhdx_region_entry_le_import(VHDXRegionTableEntry *e)
167 {
168     assert(e != NULL);
169 
170     leguid_to_cpus(&e->guid);
171     e->file_offset = le64_to_cpu(e->file_offset);
172     e->length = le32_to_cpu(e->length);
173     e->data_bits = le32_to_cpu(e->data_bits);
174 }
175 
vhdx_region_entry_le_export(VHDXRegionTableEntry * e)176 void vhdx_region_entry_le_export(VHDXRegionTableEntry *e)
177 {
178     assert(e != NULL);
179 
180     cpu_to_leguids(&e->guid);
181     e->file_offset = cpu_to_le64(e->file_offset);
182     e->length = cpu_to_le32(e->length);
183     e->data_bits = cpu_to_le32(e->data_bits);
184 }
185 
186 
187 /* Metadata headers & table */
vhdx_metadata_header_le_import(VHDXMetadataTableHeader * hdr)188 void vhdx_metadata_header_le_import(VHDXMetadataTableHeader *hdr)
189 {
190     assert(hdr != NULL);
191 
192     hdr->signature = le64_to_cpu(hdr->signature);
193     hdr->entry_count = le16_to_cpu(hdr->entry_count);
194 }
195 
vhdx_metadata_header_le_export(VHDXMetadataTableHeader * hdr)196 void vhdx_metadata_header_le_export(VHDXMetadataTableHeader *hdr)
197 {
198     assert(hdr != NULL);
199 
200     hdr->signature = cpu_to_le64(hdr->signature);
201     hdr->entry_count = cpu_to_le16(hdr->entry_count);
202 }
203 
vhdx_metadata_entry_le_import(VHDXMetadataTableEntry * e)204 void vhdx_metadata_entry_le_import(VHDXMetadataTableEntry *e)
205 {
206     assert(e != NULL);
207 
208     leguid_to_cpus(&e->item_id);
209     e->offset = le32_to_cpu(e->offset);
210     e->length = le32_to_cpu(e->length);
211     e->data_bits = le32_to_cpu(e->data_bits);
212 }
vhdx_metadata_entry_le_export(VHDXMetadataTableEntry * e)213 void vhdx_metadata_entry_le_export(VHDXMetadataTableEntry *e)
214 {
215     assert(e != NULL);
216 
217     cpu_to_leguids(&e->item_id);
218     e->offset = cpu_to_le32(e->offset);
219     e->length = cpu_to_le32(e->length);
220     e->data_bits = cpu_to_le32(e->data_bits);
221 }
222