blob: d7078c0775c184e638202af4c79f76b34fb44fb0 [file] [log] [blame]
bellarda8753c32005-04-26 21:34:00 +00001/*
2 * Block driver for the various disk image formats used by Bochs
3 * Currently only for "growing" type in read-only mode
ths5fafdf22007-09-16 21:08:06 +00004 *
bellarda8753c32005-04-26 21:34:00 +00005 * Copyright (c) 2005 Alex Beregszaszi
ths5fafdf22007-09-16 21:08:06 +00006 *
bellarda8753c32005-04-26 21:34:00 +00007 * Permission is hereby granted, free of charge, to any person obtaining a copy
8 * of this software and associated documentation files (the "Software"), to deal
9 * in the Software without restriction, including without limitation the rights
10 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11 * copies of the Software, and to permit persons to whom the Software is
12 * furnished to do so, subject to the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be included in
15 * all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23 * THE SOFTWARE.
24 */
pbrookfaf07962007-11-11 02:51:17 +000025#include "qemu-common.h"
Paolo Bonzini737e1502012-12-17 18:19:44 +010026#include "block/block_int.h"
Paolo Bonzini1de7afc2012-12-17 18:20:00 +010027#include "qemu/module.h"
bellarda8753c32005-04-26 21:34:00 +000028
29/**************************************************************/
30
31#define HEADER_MAGIC "Bochs Virtual HD Image"
ths6850dd92007-01-05 18:56:04 +000032#define HEADER_VERSION 0x00020000
33#define HEADER_V1 0x00010000
bellarda8753c32005-04-26 21:34:00 +000034#define HEADER_SIZE 512
35
36#define REDOLOG_TYPE "Redolog"
37#define GROWING_TYPE "Growing"
38
39// not allocated: 0xffffffff
40
41// always little-endian
ths6850dd92007-01-05 18:56:04 +000042struct bochs_header_v1 {
43 char magic[32]; // "Bochs Virtual HD Image"
44 char type[16]; // "Redolog"
45 char subtype[16]; // "Undoable" / "Volatile" / "Growing"
46 uint32_t version;
47 uint32_t header; // size of header
ths3b46e622007-09-17 08:09:54 +000048
ths6850dd92007-01-05 18:56:04 +000049 union {
50 struct {
51 uint32_t catalog; // num of entries
52 uint32_t bitmap; // bitmap size
53 uint32_t extent; // extent size
54 uint64_t disk; // disk size
55 char padding[HEADER_SIZE - 64 - 8 - 20];
56 } redolog;
57 char padding[HEADER_SIZE - 64 - 8];
58 } extra;
59};
60
61// always little-endian
bellarda8753c32005-04-26 21:34:00 +000062struct bochs_header {
63 char magic[32]; // "Bochs Virtual HD Image"
64 char type[16]; // "Redolog"
65 char subtype[16]; // "Undoable" / "Volatile" / "Growing"
66 uint32_t version;
67 uint32_t header; // size of header
ths3b46e622007-09-17 08:09:54 +000068
bellarda8753c32005-04-26 21:34:00 +000069 union {
70 struct {
71 uint32_t catalog; // num of entries
72 uint32_t bitmap; // bitmap size
73 uint32_t extent; // extent size
ths6850dd92007-01-05 18:56:04 +000074 uint32_t reserved; // for ???
bellarda8753c32005-04-26 21:34:00 +000075 uint64_t disk; // disk size
ths6850dd92007-01-05 18:56:04 +000076 char padding[HEADER_SIZE - 64 - 8 - 24];
bellarda8753c32005-04-26 21:34:00 +000077 } redolog;
78 char padding[HEADER_SIZE - 64 - 8];
79 } extra;
80};
81
82typedef struct BDRVBochsState {
Paolo Bonzini848c66e2011-10-20 13:16:21 +020083 CoMutex lock;
bellarda8753c32005-04-26 21:34:00 +000084 uint32_t *catalog_bitmap;
85 int catalog_size;
ths3b46e622007-09-17 08:09:54 +000086
bellarda8753c32005-04-26 21:34:00 +000087 int data_offset;
ths3b46e622007-09-17 08:09:54 +000088
bellarda8753c32005-04-26 21:34:00 +000089 int bitmap_blocks;
90 int extent_blocks;
91 int extent_size;
92} BDRVBochsState;
93
94static int bochs_probe(const uint8_t *buf, int buf_size, const char *filename)
95{
96 const struct bochs_header *bochs = (const void *)buf;
ths3b46e622007-09-17 08:09:54 +000097
bellarda8753c32005-04-26 21:34:00 +000098 if (buf_size < HEADER_SIZE)
99 return 0;
100
101 if (!strcmp(bochs->magic, HEADER_MAGIC) &&
102 !strcmp(bochs->type, REDOLOG_TYPE) &&
103 !strcmp(bochs->subtype, GROWING_TYPE) &&
ths6850dd92007-01-05 18:56:04 +0000104 ((le32_to_cpu(bochs->version) == HEADER_VERSION) ||
105 (le32_to_cpu(bochs->version) == HEADER_V1)))
bellarda8753c32005-04-26 21:34:00 +0000106 return 100;
107
108 return 0;
109}
110
Kevin Wolf1a869382013-03-15 10:35:01 +0100111static int bochs_open(BlockDriverState *bs, QDict *options, int flags)
bellarda8753c32005-04-26 21:34:00 +0000112{
113 BDRVBochsState *s = bs->opaque;
Christoph Hellwig7a6f3912010-05-04 12:44:21 +0200114 int i;
bellarda8753c32005-04-26 21:34:00 +0000115 struct bochs_header bochs;
ths6850dd92007-01-05 18:56:04 +0000116 struct bochs_header_v1 header_v1;
Kevin Wolf5b7d7df2013-01-25 17:07:27 +0100117 int ret;
bellarda8753c32005-04-26 21:34:00 +0000118
bellarda8753c32005-04-26 21:34:00 +0000119 bs->read_only = 1; // no write support yet
ths3b46e622007-09-17 08:09:54 +0000120
Kevin Wolf5b7d7df2013-01-25 17:07:27 +0100121 ret = bdrv_pread(bs->file, 0, &bochs, sizeof(bochs));
122 if (ret < 0) {
123 return ret;
bellarda8753c32005-04-26 21:34:00 +0000124 }
125
126 if (strcmp(bochs.magic, HEADER_MAGIC) ||
127 strcmp(bochs.type, REDOLOG_TYPE) ||
128 strcmp(bochs.subtype, GROWING_TYPE) ||
ths6850dd92007-01-05 18:56:04 +0000129 ((le32_to_cpu(bochs.version) != HEADER_VERSION) &&
130 (le32_to_cpu(bochs.version) != HEADER_V1))) {
Stefan Weil15bac0d2013-01-17 21:45:25 +0100131 return -EMEDIUMTYPE;
bellarda8753c32005-04-26 21:34:00 +0000132 }
133
ths6850dd92007-01-05 18:56:04 +0000134 if (le32_to_cpu(bochs.version) == HEADER_V1) {
135 memcpy(&header_v1, &bochs, sizeof(bochs));
136 bs->total_sectors = le64_to_cpu(header_v1.extra.redolog.disk) / 512;
137 } else {
138 bs->total_sectors = le64_to_cpu(bochs.extra.redolog.disk) / 512;
139 }
bellarda8753c32005-04-26 21:34:00 +0000140
bellarda8753c32005-04-26 21:34:00 +0000141 s->catalog_size = le32_to_cpu(bochs.extra.redolog.catalog);
Anthony Liguori7267c092011-08-20 22:09:37 -0500142 s->catalog_bitmap = g_malloc(s->catalog_size * 4);
Kevin Wolf5b7d7df2013-01-25 17:07:27 +0100143
144 ret = bdrv_pread(bs->file, le32_to_cpu(bochs.header), s->catalog_bitmap,
145 s->catalog_size * 4);
146 if (ret < 0) {
147 goto fail;
148 }
149
bellarda8753c32005-04-26 21:34:00 +0000150 for (i = 0; i < s->catalog_size; i++)
151 le32_to_cpus(&s->catalog_bitmap[i]);
152
153 s->data_offset = le32_to_cpu(bochs.header) + (s->catalog_size * 4);
154
155 s->bitmap_blocks = 1 + (le32_to_cpu(bochs.extra.redolog.bitmap) - 1) / 512;
156 s->extent_blocks = 1 + (le32_to_cpu(bochs.extra.redolog.extent) - 1) / 512;
ths3b46e622007-09-17 08:09:54 +0000157
bellarda8753c32005-04-26 21:34:00 +0000158 s->extent_size = le32_to_cpu(bochs.extra.redolog.extent);
159
Paolo Bonzini848c66e2011-10-20 13:16:21 +0200160 qemu_co_mutex_init(&s->lock);
bellarda8753c32005-04-26 21:34:00 +0000161 return 0;
Kevin Wolf5b7d7df2013-01-25 17:07:27 +0100162
163fail:
164 g_free(s->catalog_bitmap);
165 return ret;
bellarda8753c32005-04-26 21:34:00 +0000166}
167
Christoph Hellwigefbca102010-05-04 12:44:08 +0200168static int64_t seek_to_sector(BlockDriverState *bs, int64_t sector_num)
bellarda8753c32005-04-26 21:34:00 +0000169{
170 BDRVBochsState *s = bs->opaque;
171 int64_t offset = sector_num * 512;
Christoph Hellwigefbca102010-05-04 12:44:08 +0200172 int64_t extent_index, extent_offset, bitmap_offset;
bellarda8753c32005-04-26 21:34:00 +0000173 char bitmap_entry;
174
175 // seek to sector
176 extent_index = offset / s->extent_size;
177 extent_offset = (offset % s->extent_size) / 512;
ths3b46e622007-09-17 08:09:54 +0000178
Christoph Hellwigefbca102010-05-04 12:44:08 +0200179 if (s->catalog_bitmap[extent_index] == 0xffffffff) {
180 return -1; /* not allocated */
bellarda8753c32005-04-26 21:34:00 +0000181 }
182
183 bitmap_offset = s->data_offset + (512 * s->catalog_bitmap[extent_index] *
184 (s->extent_blocks + s->bitmap_blocks));
ths3b46e622007-09-17 08:09:54 +0000185
Christoph Hellwigefbca102010-05-04 12:44:08 +0200186 /* read in bitmap for current extent */
Christoph Hellwig7a6f3912010-05-04 12:44:21 +0200187 if (bdrv_pread(bs->file, bitmap_offset + (extent_offset / 8),
188 &bitmap_entry, 1) != 1) {
Blue Swirlecbe1572009-12-25 19:27:18 +0000189 return -1;
190 }
ths3b46e622007-09-17 08:09:54 +0000191
Christoph Hellwigefbca102010-05-04 12:44:08 +0200192 if (!((bitmap_entry >> (extent_offset % 8)) & 1)) {
193 return -1; /* not allocated */
bellarda8753c32005-04-26 21:34:00 +0000194 }
195
Christoph Hellwigefbca102010-05-04 12:44:08 +0200196 return bitmap_offset + (512 * (s->bitmap_blocks + extent_offset));
bellarda8753c32005-04-26 21:34:00 +0000197}
198
ths5fafdf22007-09-16 21:08:06 +0000199static int bochs_read(BlockDriverState *bs, int64_t sector_num,
bellarda8753c32005-04-26 21:34:00 +0000200 uint8_t *buf, int nb_sectors)
201{
bellarda8753c32005-04-26 21:34:00 +0000202 int ret;
203
204 while (nb_sectors > 0) {
Christoph Hellwigefbca102010-05-04 12:44:08 +0200205 int64_t block_offset = seek_to_sector(bs, sector_num);
206 if (block_offset >= 0) {
Christoph Hellwig7a6f3912010-05-04 12:44:21 +0200207 ret = bdrv_pread(bs->file, block_offset, buf, 512);
Christoph Hellwigefbca102010-05-04 12:44:08 +0200208 if (ret != 512) {
209 return -1;
210 }
211 } else
bellarda8753c32005-04-26 21:34:00 +0000212 memset(buf, 0, 512);
213 nb_sectors--;
214 sector_num++;
215 buf += 512;
216 }
217 return 0;
218}
219
Paolo Bonzini2914caa2011-10-20 13:16:22 +0200220static coroutine_fn int bochs_co_read(BlockDriverState *bs, int64_t sector_num,
221 uint8_t *buf, int nb_sectors)
222{
223 int ret;
224 BDRVBochsState *s = bs->opaque;
225 qemu_co_mutex_lock(&s->lock);
226 ret = bochs_read(bs, sector_num, buf, nb_sectors);
227 qemu_co_mutex_unlock(&s->lock);
228 return ret;
229}
230
bellarda8753c32005-04-26 21:34:00 +0000231static void bochs_close(BlockDriverState *bs)
232{
233 BDRVBochsState *s = bs->opaque;
Anthony Liguori7267c092011-08-20 22:09:37 -0500234 g_free(s->catalog_bitmap);
bellarda8753c32005-04-26 21:34:00 +0000235}
236
Anthony Liguori5efa9d52009-05-09 17:03:42 -0500237static BlockDriver bdrv_bochs = {
aurel32e60f4692009-03-07 22:00:29 +0000238 .format_name = "bochs",
239 .instance_size = sizeof(BDRVBochsState),
240 .bdrv_probe = bochs_probe,
Christoph Hellwig7a6f3912010-05-04 12:44:21 +0200241 .bdrv_open = bochs_open,
Paolo Bonzini2914caa2011-10-20 13:16:22 +0200242 .bdrv_read = bochs_co_read,
aurel32e60f4692009-03-07 22:00:29 +0000243 .bdrv_close = bochs_close,
bellarda8753c32005-04-26 21:34:00 +0000244};
Anthony Liguori5efa9d52009-05-09 17:03:42 -0500245
246static void bdrv_bochs_init(void)
247{
248 bdrv_register(&bdrv_bochs);
249}
250
251block_init(bdrv_bochs_init);