xref: /qemu/block/vhdx-endian.c (revision 72ac97cd)
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 }
217