xref: /openbmc/qemu/block/vhdx-endian.c (revision dc5bd18f)
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 }
223