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1 | a8753c34 | bellard | /*
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2 | a8753c34 | bellard | * Block driver for the various disk image formats used by Bochs
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3 | a8753c34 | bellard | * Currently only for "growing" type in read-only mode
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4 | 5fafdf24 | ths | *
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5 | a8753c34 | bellard | * Copyright (c) 2005 Alex Beregszaszi
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6 | 5fafdf24 | ths | *
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7 | a8753c34 | bellard | * Permission is hereby granted, free of charge, to any person obtaining a copy
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8 | a8753c34 | bellard | * of this software and associated documentation files (the "Software"), to deal
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9 | a8753c34 | bellard | * in the Software without restriction, including without limitation the rights
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10 | a8753c34 | bellard | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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11 | a8753c34 | bellard | * copies of the Software, and to permit persons to whom the Software is
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12 | a8753c34 | bellard | * furnished to do so, subject to the following conditions:
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13 | a8753c34 | bellard | *
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14 | a8753c34 | bellard | * The above copyright notice and this permission notice shall be included in
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15 | a8753c34 | bellard | * all copies or substantial portions of the Software.
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16 | a8753c34 | bellard | *
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17 | a8753c34 | bellard | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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18 | a8753c34 | bellard | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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19 | a8753c34 | bellard | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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20 | a8753c34 | bellard | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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21 | a8753c34 | bellard | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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22 | a8753c34 | bellard | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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23 | a8753c34 | bellard | * THE SOFTWARE.
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24 | a8753c34 | bellard | */
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25 | faf07963 | pbrook | #include "qemu-common.h" |
26 | a8753c34 | bellard | #include "block_int.h" |
27 | 5efa9d5a | Anthony Liguori | #include "module.h" |
28 | a8753c34 | bellard | |
29 | a8753c34 | bellard | /**************************************************************/
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30 | a8753c34 | bellard | |
31 | a8753c34 | bellard | #define HEADER_MAGIC "Bochs Virtual HD Image" |
32 | 6850dd94 | ths | #define HEADER_VERSION 0x00020000 |
33 | 6850dd94 | ths | #define HEADER_V1 0x00010000 |
34 | a8753c34 | bellard | #define HEADER_SIZE 512 |
35 | a8753c34 | bellard | |
36 | a8753c34 | bellard | #define REDOLOG_TYPE "Redolog" |
37 | a8753c34 | bellard | #define GROWING_TYPE "Growing" |
38 | a8753c34 | bellard | |
39 | a8753c34 | bellard | // not allocated: 0xffffffff
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40 | a8753c34 | bellard | |
41 | a8753c34 | bellard | // always little-endian
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42 | 6850dd94 | ths | struct bochs_header_v1 {
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43 | a8753c34 | bellard | char magic[32]; // "Bochs Virtual HD Image" |
44 | a8753c34 | bellard | char type[16]; // "Redolog" |
45 | a8753c34 | bellard | char subtype[16]; // "Undoable" / "Volatile" / "Growing" |
46 | a8753c34 | bellard | uint32_t version; |
47 | a8753c34 | bellard | uint32_t header; // size of header
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48 | 3b46e624 | ths | |
49 | a8753c34 | bellard | union {
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50 | a8753c34 | bellard | struct {
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51 | a8753c34 | bellard | uint32_t catalog; // num of entries
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52 | a8753c34 | bellard | uint32_t bitmap; // bitmap size
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53 | a8753c34 | bellard | uint32_t extent; // extent size
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54 | a8753c34 | bellard | uint64_t disk; // disk size
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55 | a8753c34 | bellard | char padding[HEADER_SIZE - 64 - 8 - 20]; |
56 | a8753c34 | bellard | } redolog; |
57 | a8753c34 | bellard | char padding[HEADER_SIZE - 64 - 8]; |
58 | a8753c34 | bellard | } extra; |
59 | a8753c34 | bellard | }; |
60 | a8753c34 | bellard | |
61 | 6850dd94 | ths | // always little-endian
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62 | 6850dd94 | ths | struct bochs_header {
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63 | 6850dd94 | ths | char magic[32]; // "Bochs Virtual HD Image" |
64 | 6850dd94 | ths | char type[16]; // "Redolog" |
65 | 6850dd94 | ths | char subtype[16]; // "Undoable" / "Volatile" / "Growing" |
66 | 6850dd94 | ths | uint32_t version; |
67 | 6850dd94 | ths | uint32_t header; // size of header
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68 | 3b46e624 | ths | |
69 | 6850dd94 | ths | union {
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70 | 6850dd94 | ths | struct {
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71 | 6850dd94 | ths | uint32_t catalog; // num of entries
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72 | 6850dd94 | ths | uint32_t bitmap; // bitmap size
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73 | 6850dd94 | ths | uint32_t extent; // extent size
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74 | 6850dd94 | ths | uint32_t reserved; // for ???
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75 | 6850dd94 | ths | uint64_t disk; // disk size
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76 | 6850dd94 | ths | char padding[HEADER_SIZE - 64 - 8 - 24]; |
77 | 6850dd94 | ths | } redolog; |
78 | 6850dd94 | ths | char padding[HEADER_SIZE - 64 - 8]; |
79 | 6850dd94 | ths | } extra; |
80 | 6850dd94 | ths | }; |
81 | 6850dd94 | ths | |
82 | a8753c34 | bellard | typedef struct BDRVBochsState { |
83 | a8753c34 | bellard | uint32_t *catalog_bitmap; |
84 | a8753c34 | bellard | int catalog_size;
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85 | 3b46e624 | ths | |
86 | a8753c34 | bellard | int data_offset;
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87 | 3b46e624 | ths | |
88 | a8753c34 | bellard | int bitmap_blocks;
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89 | a8753c34 | bellard | int extent_blocks;
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90 | a8753c34 | bellard | int extent_size;
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91 | a8753c34 | bellard | } BDRVBochsState; |
92 | a8753c34 | bellard | |
93 | a8753c34 | bellard | static int bochs_probe(const uint8_t *buf, int buf_size, const char *filename) |
94 | a8753c34 | bellard | { |
95 | a8753c34 | bellard | const struct bochs_header *bochs = (const void *)buf; |
96 | 3b46e624 | ths | |
97 | a8753c34 | bellard | if (buf_size < HEADER_SIZE)
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98 | a8753c34 | bellard | return 0; |
99 | a8753c34 | bellard | |
100 | a8753c34 | bellard | if (!strcmp(bochs->magic, HEADER_MAGIC) &&
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101 | a8753c34 | bellard | !strcmp(bochs->type, REDOLOG_TYPE) && |
102 | a8753c34 | bellard | !strcmp(bochs->subtype, GROWING_TYPE) && |
103 | 6850dd94 | ths | ((le32_to_cpu(bochs->version) == HEADER_VERSION) || |
104 | 6850dd94 | ths | (le32_to_cpu(bochs->version) == HEADER_V1))) |
105 | a8753c34 | bellard | return 100; |
106 | a8753c34 | bellard | |
107 | a8753c34 | bellard | return 0; |
108 | a8753c34 | bellard | } |
109 | a8753c34 | bellard | |
110 | 7a6f3913 | Christoph Hellwig | static int bochs_open(BlockDriverState *bs, int flags) |
111 | a8753c34 | bellard | { |
112 | a8753c34 | bellard | BDRVBochsState *s = bs->opaque; |
113 | 7a6f3913 | Christoph Hellwig | int i;
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114 | a8753c34 | bellard | struct bochs_header bochs;
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115 | 6850dd94 | ths | struct bochs_header_v1 header_v1;
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116 | a8753c34 | bellard | |
117 | a8753c34 | bellard | bs->read_only = 1; // no write support yet |
118 | 3b46e624 | ths | |
119 | 7a6f3913 | Christoph Hellwig | if (bdrv_pread(bs->file, 0, &bochs, sizeof(bochs)) != sizeof(bochs)) { |
120 | a8753c34 | bellard | goto fail;
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121 | a8753c34 | bellard | } |
122 | a8753c34 | bellard | |
123 | a8753c34 | bellard | if (strcmp(bochs.magic, HEADER_MAGIC) ||
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124 | a8753c34 | bellard | strcmp(bochs.type, REDOLOG_TYPE) || |
125 | a8753c34 | bellard | strcmp(bochs.subtype, GROWING_TYPE) || |
126 | 6850dd94 | ths | ((le32_to_cpu(bochs.version) != HEADER_VERSION) && |
127 | 6850dd94 | ths | (le32_to_cpu(bochs.version) != HEADER_V1))) { |
128 | a8753c34 | bellard | goto fail;
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129 | a8753c34 | bellard | } |
130 | a8753c34 | bellard | |
131 | 6850dd94 | ths | if (le32_to_cpu(bochs.version) == HEADER_V1) {
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132 | 6850dd94 | ths | memcpy(&header_v1, &bochs, sizeof(bochs));
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133 | 6850dd94 | ths | bs->total_sectors = le64_to_cpu(header_v1.extra.redolog.disk) / 512;
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134 | 6850dd94 | ths | } else {
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135 | 6850dd94 | ths | bs->total_sectors = le64_to_cpu(bochs.extra.redolog.disk) / 512;
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136 | 6850dd94 | ths | } |
137 | a8753c34 | bellard | |
138 | a8753c34 | bellard | s->catalog_size = le32_to_cpu(bochs.extra.redolog.catalog); |
139 | a8753c34 | bellard | s->catalog_bitmap = qemu_malloc(s->catalog_size * 4);
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140 | 7a6f3913 | Christoph Hellwig | if (bdrv_pread(bs->file, le32_to_cpu(bochs.header), s->catalog_bitmap,
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141 | 7a6f3913 | Christoph Hellwig | s->catalog_size * 4) != s->catalog_size * 4) |
142 | a8753c34 | bellard | goto fail;
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143 | a8753c34 | bellard | for (i = 0; i < s->catalog_size; i++) |
144 | a8753c34 | bellard | le32_to_cpus(&s->catalog_bitmap[i]); |
145 | a8753c34 | bellard | |
146 | a8753c34 | bellard | s->data_offset = le32_to_cpu(bochs.header) + (s->catalog_size * 4);
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147 | a8753c34 | bellard | |
148 | a8753c34 | bellard | s->bitmap_blocks = 1 + (le32_to_cpu(bochs.extra.redolog.bitmap) - 1) / 512; |
149 | a8753c34 | bellard | s->extent_blocks = 1 + (le32_to_cpu(bochs.extra.redolog.extent) - 1) / 512; |
150 | 3b46e624 | ths | |
151 | a8753c34 | bellard | s->extent_size = le32_to_cpu(bochs.extra.redolog.extent); |
152 | a8753c34 | bellard | |
153 | a8753c34 | bellard | return 0; |
154 | a8753c34 | bellard | fail:
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155 | a8753c34 | bellard | return -1; |
156 | a8753c34 | bellard | } |
157 | a8753c34 | bellard | |
158 | efbca10f | Christoph Hellwig | static int64_t seek_to_sector(BlockDriverState *bs, int64_t sector_num)
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159 | a8753c34 | bellard | { |
160 | a8753c34 | bellard | BDRVBochsState *s = bs->opaque; |
161 | a8753c34 | bellard | int64_t offset = sector_num * 512;
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162 | efbca10f | Christoph Hellwig | int64_t extent_index, extent_offset, bitmap_offset; |
163 | a8753c34 | bellard | char bitmap_entry;
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164 | a8753c34 | bellard | |
165 | a8753c34 | bellard | // seek to sector
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166 | a8753c34 | bellard | extent_index = offset / s->extent_size; |
167 | a8753c34 | bellard | extent_offset = (offset % s->extent_size) / 512;
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168 | 3b46e624 | ths | |
169 | efbca10f | Christoph Hellwig | if (s->catalog_bitmap[extent_index] == 0xffffffff) { |
170 | efbca10f | Christoph Hellwig | return -1; /* not allocated */ |
171 | a8753c34 | bellard | } |
172 | a8753c34 | bellard | |
173 | a8753c34 | bellard | bitmap_offset = s->data_offset + (512 * s->catalog_bitmap[extent_index] *
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174 | a8753c34 | bellard | (s->extent_blocks + s->bitmap_blocks)); |
175 | 3b46e624 | ths | |
176 | efbca10f | Christoph Hellwig | /* read in bitmap for current extent */
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177 | 7a6f3913 | Christoph Hellwig | if (bdrv_pread(bs->file, bitmap_offset + (extent_offset / 8), |
178 | 7a6f3913 | Christoph Hellwig | &bitmap_entry, 1) != 1) { |
179 | 00ccf932 | Kirill A. Shutemov | return -1; |
180 | a8753c34 | bellard | } |
181 | a8753c34 | bellard | |
182 | efbca10f | Christoph Hellwig | if (!((bitmap_entry >> (extent_offset % 8)) & 1)) { |
183 | efbca10f | Christoph Hellwig | return -1; /* not allocated */ |
184 | ecbe1576 | Blue Swirl | } |
185 | 3b46e624 | ths | |
186 | efbca10f | Christoph Hellwig | return bitmap_offset + (512 * (s->bitmap_blocks + extent_offset)); |
187 | a8753c34 | bellard | } |
188 | a8753c34 | bellard | |
189 | 5fafdf24 | ths | static int bochs_read(BlockDriverState *bs, int64_t sector_num, |
190 | a8753c34 | bellard | uint8_t *buf, int nb_sectors)
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191 | a8753c34 | bellard | { |
192 | a8753c34 | bellard | int ret;
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193 | a8753c34 | bellard | |
194 | a8753c34 | bellard | while (nb_sectors > 0) { |
195 | efbca10f | Christoph Hellwig | int64_t block_offset = seek_to_sector(bs, sector_num); |
196 | efbca10f | Christoph Hellwig | if (block_offset >= 0) { |
197 | 7a6f3913 | Christoph Hellwig | ret = bdrv_pread(bs->file, block_offset, buf, 512);
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198 | efbca10f | Christoph Hellwig | if (ret != 512) { |
199 | efbca10f | Christoph Hellwig | return -1; |
200 | efbca10f | Christoph Hellwig | } |
201 | efbca10f | Christoph Hellwig | } else
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202 | a8753c34 | bellard | memset(buf, 0, 512); |
203 | a8753c34 | bellard | nb_sectors--; |
204 | a8753c34 | bellard | sector_num++; |
205 | a8753c34 | bellard | buf += 512;
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206 | a8753c34 | bellard | } |
207 | a8753c34 | bellard | return 0; |
208 | a8753c34 | bellard | } |
209 | a8753c34 | bellard | |
210 | a8753c34 | bellard | static void bochs_close(BlockDriverState *bs) |
211 | a8753c34 | bellard | { |
212 | a8753c34 | bellard | BDRVBochsState *s = bs->opaque; |
213 | a8753c34 | bellard | qemu_free(s->catalog_bitmap); |
214 | a8753c34 | bellard | } |
215 | a8753c34 | bellard | |
216 | 5efa9d5a | Anthony Liguori | static BlockDriver bdrv_bochs = {
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217 | e60f469c | aurel32 | .format_name = "bochs",
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218 | e60f469c | aurel32 | .instance_size = sizeof(BDRVBochsState),
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219 | e60f469c | aurel32 | .bdrv_probe = bochs_probe, |
220 | 7a6f3913 | Christoph Hellwig | .bdrv_open = bochs_open, |
221 | e60f469c | aurel32 | .bdrv_read = bochs_read, |
222 | e60f469c | aurel32 | .bdrv_close = bochs_close, |
223 | a8753c34 | bellard | }; |
224 | 5efa9d5a | Anthony Liguori | |
225 | 5efa9d5a | Anthony Liguori | static void bdrv_bochs_init(void) |
226 | 5efa9d5a | Anthony Liguori | { |
227 | 5efa9d5a | Anthony Liguori | bdrv_register(&bdrv_bochs); |
228 | 5efa9d5a | Anthony Liguori | } |
229 | 5efa9d5a | Anthony Liguori | |
230 | 5efa9d5a | Anthony Liguori | block_init(bdrv_bochs_init); |