bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 1 | /* |
Stefan Weil | cc2040f | 2009-08-31 21:42:16 +0200 | [diff] [blame] | 2 | * Block driver for Connectix / Microsoft Virtual PC images |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 3 | * |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 4 | * Copyright (c) 2005 Alex Beregszaszi |
aliguori | 15d35bc | 2009-01-26 20:27:02 +0000 | [diff] [blame] | 5 | * Copyright (c) 2009 Kevin Wolf <kwolf@suse.de> |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 6 | * |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 7 | * 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 | */ |
pbrook | faf0796 | 2007-11-11 02:51:17 +0000 | [diff] [blame] | 25 | #include "qemu-common.h" |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 26 | #include "block_int.h" |
Anthony Liguori | 5efa9d5 | 2009-05-09 17:03:42 -0500 | [diff] [blame] | 27 | #include "module.h" |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 28 | |
| 29 | /**************************************************************/ |
| 30 | |
| 31 | #define HEADER_SIZE 512 |
| 32 | |
| 33 | //#define CACHE |
| 34 | |
aliguori | 2cfacb6 | 2009-01-26 20:26:49 +0000 | [diff] [blame] | 35 | enum vhd_type { |
| 36 | VHD_FIXED = 2, |
| 37 | VHD_DYNAMIC = 3, |
| 38 | VHD_DIFFERENCING = 4, |
| 39 | }; |
| 40 | |
aliguori | 57c7d9e | 2009-01-26 20:27:06 +0000 | [diff] [blame] | 41 | // Seconds since Jan 1, 2000 0:00:00 (UTC) |
| 42 | #define VHD_TIMESTAMP_BASE 946684800 |
| 43 | |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 44 | // always big-endian |
aliguori | b9fa33a | 2009-01-26 20:26:46 +0000 | [diff] [blame] | 45 | struct vhd_footer { |
aliguori | 2cfacb6 | 2009-01-26 20:26:49 +0000 | [diff] [blame] | 46 | char creator[8]; // "conectix" |
| 47 | uint32_t features; |
| 48 | uint32_t version; |
| 49 | |
| 50 | // Offset of next header structure, 0xFFFFFFFF if none |
| 51 | uint64_t data_offset; |
| 52 | |
| 53 | // Seconds since Jan 1, 2000 0:00:00 (UTC) |
| 54 | uint32_t timestamp; |
| 55 | |
| 56 | char creator_app[4]; // "vpc " |
| 57 | uint16_t major; |
| 58 | uint16_t minor; |
| 59 | char creator_os[4]; // "Wi2k" |
| 60 | |
| 61 | uint64_t orig_size; |
| 62 | uint64_t size; |
| 63 | |
| 64 | uint16_t cyls; |
| 65 | uint8_t heads; |
| 66 | uint8_t secs_per_cyl; |
| 67 | |
| 68 | uint32_t type; |
| 69 | |
| 70 | // Checksum of the Hard Disk Footer ("one's complement of the sum of all |
| 71 | // the bytes in the footer without the checksum field") |
| 72 | uint32_t checksum; |
| 73 | |
| 74 | // UUID used to identify a parent hard disk (backing file) |
| 75 | uint8_t uuid[16]; |
| 76 | |
| 77 | uint8_t in_saved_state; |
aliguori | b9fa33a | 2009-01-26 20:26:46 +0000 | [diff] [blame] | 78 | }; |
| 79 | |
| 80 | struct vhd_dyndisk_header { |
aliguori | 2cfacb6 | 2009-01-26 20:26:49 +0000 | [diff] [blame] | 81 | char magic[8]; // "cxsparse" |
| 82 | |
| 83 | // Offset of next header structure, 0xFFFFFFFF if none |
| 84 | uint64_t data_offset; |
| 85 | |
| 86 | // Offset of the Block Allocation Table (BAT) |
| 87 | uint64_t table_offset; |
| 88 | |
| 89 | uint32_t version; |
| 90 | uint32_t max_table_entries; // 32bit/entry |
| 91 | |
| 92 | // 2 MB by default, must be a power of two |
| 93 | uint32_t block_size; |
| 94 | |
| 95 | uint32_t checksum; |
| 96 | uint8_t parent_uuid[16]; |
| 97 | uint32_t parent_timestamp; |
| 98 | uint32_t reserved; |
| 99 | |
| 100 | // Backing file name (in UTF-16) |
| 101 | uint8_t parent_name[512]; |
| 102 | |
| 103 | struct { |
| 104 | uint32_t platform; |
| 105 | uint32_t data_space; |
| 106 | uint32_t data_length; |
| 107 | uint32_t reserved; |
| 108 | uint64_t data_offset; |
| 109 | } parent_locator[8]; |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 110 | }; |
| 111 | |
| 112 | typedef struct BDRVVPCState { |
aliguori | b71d1c2 | 2009-01-26 20:26:58 +0000 | [diff] [blame] | 113 | BlockDriverState *hd; |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 114 | |
aliguori | 15d35bc | 2009-01-26 20:27:02 +0000 | [diff] [blame] | 115 | uint8_t footer_buf[HEADER_SIZE]; |
| 116 | uint64_t free_data_block_offset; |
aliguori | 2cfacb6 | 2009-01-26 20:26:49 +0000 | [diff] [blame] | 117 | int max_table_entries; |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 118 | uint32_t *pagetable; |
aliguori | 15d35bc | 2009-01-26 20:27:02 +0000 | [diff] [blame] | 119 | uint64_t bat_offset; |
| 120 | uint64_t last_bitmap_offset; |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 121 | |
aliguori | 2cfacb6 | 2009-01-26 20:26:49 +0000 | [diff] [blame] | 122 | uint32_t block_size; |
aliguori | 15d35bc | 2009-01-26 20:27:02 +0000 | [diff] [blame] | 123 | uint32_t bitmap_size; |
| 124 | |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 125 | #ifdef CACHE |
| 126 | uint8_t *pageentry_u8; |
| 127 | uint32_t *pageentry_u32; |
| 128 | uint16_t *pageentry_u16; |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 129 | |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 130 | uint64_t last_bitmap; |
| 131 | #endif |
| 132 | } BDRVVPCState; |
| 133 | |
aliguori | 57c7d9e | 2009-01-26 20:27:06 +0000 | [diff] [blame] | 134 | static uint32_t vpc_checksum(uint8_t* buf, size_t size) |
| 135 | { |
| 136 | uint32_t res = 0; |
| 137 | int i; |
| 138 | |
| 139 | for (i = 0; i < size; i++) |
| 140 | res += buf[i]; |
| 141 | |
| 142 | return ~res; |
| 143 | } |
| 144 | |
| 145 | |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 146 | static int vpc_probe(const uint8_t *buf, int buf_size, const char *filename) |
| 147 | { |
ths | ffe8ab8 | 2007-12-16 03:16:05 +0000 | [diff] [blame] | 148 | if (buf_size >= 8 && !strncmp((char *)buf, "conectix", 8)) |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 149 | return 100; |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 150 | return 0; |
| 151 | } |
| 152 | |
bellard | 83f6409 | 2006-08-01 16:21:11 +0000 | [diff] [blame] | 153 | static int vpc_open(BlockDriverState *bs, const char *filename, int flags) |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 154 | { |
| 155 | BDRVVPCState *s = bs->opaque; |
aliguori | b71d1c2 | 2009-01-26 20:26:58 +0000 | [diff] [blame] | 156 | int ret, i; |
aliguori | b9fa33a | 2009-01-26 20:26:46 +0000 | [diff] [blame] | 157 | struct vhd_footer* footer; |
| 158 | struct vhd_dyndisk_header* dyndisk_header; |
| 159 | uint8_t buf[HEADER_SIZE]; |
aliguori | 57c7d9e | 2009-01-26 20:27:06 +0000 | [diff] [blame] | 160 | uint32_t checksum; |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 161 | |
aliguori | b71d1c2 | 2009-01-26 20:26:58 +0000 | [diff] [blame] | 162 | ret = bdrv_file_open(&s->hd, filename, flags); |
| 163 | if (ret < 0) |
| 164 | return ret; |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 165 | |
aliguori | 15d35bc | 2009-01-26 20:27:02 +0000 | [diff] [blame] | 166 | if (bdrv_pread(s->hd, 0, s->footer_buf, HEADER_SIZE) != HEADER_SIZE) |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 167 | goto fail; |
| 168 | |
aliguori | 15d35bc | 2009-01-26 20:27:02 +0000 | [diff] [blame] | 169 | footer = (struct vhd_footer*) s->footer_buf; |
aliguori | b9fa33a | 2009-01-26 20:26:46 +0000 | [diff] [blame] | 170 | if (strncmp(footer->creator, "conectix", 8)) |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 171 | goto fail; |
| 172 | |
aliguori | 57c7d9e | 2009-01-26 20:27:06 +0000 | [diff] [blame] | 173 | checksum = be32_to_cpu(footer->checksum); |
| 174 | footer->checksum = 0; |
| 175 | if (vpc_checksum(s->footer_buf, HEADER_SIZE) != checksum) |
| 176 | fprintf(stderr, "block-vpc: The header checksum of '%s' is " |
| 177 | "incorrect.\n", filename); |
| 178 | |
aliguori | 1fa7922 | 2009-01-26 20:26:54 +0000 | [diff] [blame] | 179 | // The visible size of a image in Virtual PC depends on the geometry |
| 180 | // rather than on the size stored in the footer (the size in the footer |
| 181 | // is too large usually) |
| 182 | bs->total_sectors = (int64_t) |
| 183 | be16_to_cpu(footer->cyls) * footer->heads * footer->secs_per_cyl; |
| 184 | |
aliguori | b71d1c2 | 2009-01-26 20:26:58 +0000 | [diff] [blame] | 185 | if (bdrv_pread(s->hd, be64_to_cpu(footer->data_offset), buf, HEADER_SIZE) |
| 186 | != HEADER_SIZE) |
aliguori | b9fa33a | 2009-01-26 20:26:46 +0000 | [diff] [blame] | 187 | goto fail; |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 188 | |
aliguori | b9fa33a | 2009-01-26 20:26:46 +0000 | [diff] [blame] | 189 | dyndisk_header = (struct vhd_dyndisk_header*) buf; |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 190 | |
aliguori | b9fa33a | 2009-01-26 20:26:46 +0000 | [diff] [blame] | 191 | if (strncmp(dyndisk_header->magic, "cxsparse", 8)) |
| 192 | goto fail; |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 193 | |
aliguori | b9fa33a | 2009-01-26 20:26:46 +0000 | [diff] [blame] | 194 | |
aliguori | 15d35bc | 2009-01-26 20:27:02 +0000 | [diff] [blame] | 195 | s->block_size = be32_to_cpu(dyndisk_header->block_size); |
| 196 | s->bitmap_size = ((s->block_size / (8 * 512)) + 511) & ~511; |
| 197 | |
aliguori | 2cfacb6 | 2009-01-26 20:26:49 +0000 | [diff] [blame] | 198 | s->max_table_entries = be32_to_cpu(dyndisk_header->max_table_entries); |
| 199 | s->pagetable = qemu_malloc(s->max_table_entries * 4); |
aliguori | b71d1c2 | 2009-01-26 20:26:58 +0000 | [diff] [blame] | 200 | |
aliguori | 15d35bc | 2009-01-26 20:27:02 +0000 | [diff] [blame] | 201 | s->bat_offset = be64_to_cpu(dyndisk_header->table_offset); |
| 202 | if (bdrv_pread(s->hd, s->bat_offset, s->pagetable, |
| 203 | s->max_table_entries * 4) != s->max_table_entries * 4) |
aliguori | b71d1c2 | 2009-01-26 20:26:58 +0000 | [diff] [blame] | 204 | goto fail; |
| 205 | |
aliguori | 15d35bc | 2009-01-26 20:27:02 +0000 | [diff] [blame] | 206 | s->free_data_block_offset = |
| 207 | (s->bat_offset + (s->max_table_entries * 4) + 511) & ~511; |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 208 | |
aliguori | 15d35bc | 2009-01-26 20:27:02 +0000 | [diff] [blame] | 209 | for (i = 0; i < s->max_table_entries; i++) { |
| 210 | be32_to_cpus(&s->pagetable[i]); |
| 211 | if (s->pagetable[i] != 0xFFFFFFFF) { |
| 212 | int64_t next = (512 * (int64_t) s->pagetable[i]) + |
| 213 | s->bitmap_size + s->block_size; |
| 214 | |
| 215 | if (next> s->free_data_block_offset) |
| 216 | s->free_data_block_offset = next; |
| 217 | } |
| 218 | } |
| 219 | |
| 220 | s->last_bitmap_offset = (int64_t) -1; |
| 221 | |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 222 | #ifdef CACHE |
| 223 | s->pageentry_u8 = qemu_malloc(512); |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 224 | s->pageentry_u32 = s->pageentry_u8; |
| 225 | s->pageentry_u16 = s->pageentry_u8; |
| 226 | s->last_pagetable = -1; |
| 227 | #endif |
| 228 | |
| 229 | return 0; |
| 230 | fail: |
aliguori | b71d1c2 | 2009-01-26 20:26:58 +0000 | [diff] [blame] | 231 | bdrv_delete(s->hd); |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 232 | return -1; |
| 233 | } |
| 234 | |
aliguori | b71d1c2 | 2009-01-26 20:26:58 +0000 | [diff] [blame] | 235 | /* |
| 236 | * Returns the absolute byte offset of the given sector in the image file. |
| 237 | * If the sector is not allocated, -1 is returned instead. |
aliguori | 15d35bc | 2009-01-26 20:27:02 +0000 | [diff] [blame] | 238 | * |
| 239 | * The parameter write must be 1 if the offset will be used for a write |
| 240 | * operation (the block bitmaps is updated then), 0 otherwise. |
aliguori | b71d1c2 | 2009-01-26 20:26:58 +0000 | [diff] [blame] | 241 | */ |
aliguori | 15d35bc | 2009-01-26 20:27:02 +0000 | [diff] [blame] | 242 | static inline int64_t get_sector_offset(BlockDriverState *bs, |
| 243 | int64_t sector_num, int write) |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 244 | { |
| 245 | BDRVVPCState *s = bs->opaque; |
| 246 | uint64_t offset = sector_num * 512; |
| 247 | uint64_t bitmap_offset, block_offset; |
| 248 | uint32_t pagetable_index, pageentry_index; |
| 249 | |
aliguori | 2cfacb6 | 2009-01-26 20:26:49 +0000 | [diff] [blame] | 250 | pagetable_index = offset / s->block_size; |
| 251 | pageentry_index = (offset % s->block_size) / 512; |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 252 | |
aliguori | 15d35bc | 2009-01-26 20:27:02 +0000 | [diff] [blame] | 253 | if (pagetable_index >= s->max_table_entries || s->pagetable[pagetable_index] == 0xffffffff) |
| 254 | return -1; // not allocated |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 255 | |
aliguori | 378e2ae | 2009-01-27 14:29:15 +0000 | [diff] [blame] | 256 | bitmap_offset = 512 * (uint64_t) s->pagetable[pagetable_index]; |
aliguori | 15d35bc | 2009-01-26 20:27:02 +0000 | [diff] [blame] | 257 | block_offset = bitmap_offset + s->bitmap_size + (512 * pageentry_index); |
| 258 | |
| 259 | // We must ensure that we don't write to any sectors which are marked as |
| 260 | // unused in the bitmap. We get away with setting all bits in the block |
| 261 | // bitmap each time we write to a new block. This might cause Virtual PC to |
| 262 | // miss sparse read optimization, but it's not a problem in terms of |
| 263 | // correctness. |
| 264 | if (write && (s->last_bitmap_offset != bitmap_offset)) { |
| 265 | uint8_t bitmap[s->bitmap_size]; |
| 266 | |
| 267 | s->last_bitmap_offset = bitmap_offset; |
| 268 | memset(bitmap, 0xff, s->bitmap_size); |
| 269 | bdrv_pwrite(s->hd, bitmap_offset, bitmap, s->bitmap_size); |
| 270 | } |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 271 | |
bellard | 26a7646 | 2006-06-25 18:15:32 +0000 | [diff] [blame] | 272 | // printf("sector: %" PRIx64 ", index: %x, offset: %x, bioff: %" PRIx64 ", bloff: %" PRIx64 "\n", |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 273 | // sector_num, pagetable_index, pageentry_index, |
| 274 | // bitmap_offset, block_offset); |
| 275 | |
| 276 | // disabled by reason |
| 277 | #if 0 |
| 278 | #ifdef CACHE |
| 279 | if (bitmap_offset != s->last_bitmap) |
| 280 | { |
| 281 | lseek(s->fd, bitmap_offset, SEEK_SET); |
| 282 | |
| 283 | s->last_bitmap = bitmap_offset; |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 284 | |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 285 | // Scary! Bitmap is stored as big endian 32bit entries, |
| 286 | // while we used to look it up byte by byte |
| 287 | read(s->fd, s->pageentry_u8, 512); |
| 288 | for (i = 0; i < 128; i++) |
| 289 | be32_to_cpus(&s->pageentry_u32[i]); |
| 290 | } |
| 291 | |
| 292 | if ((s->pageentry_u8[pageentry_index / 8] >> (pageentry_index % 8)) & 1) |
| 293 | return -1; |
| 294 | #else |
| 295 | lseek(s->fd, bitmap_offset + (pageentry_index / 8), SEEK_SET); |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 296 | |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 297 | read(s->fd, &bitmap_entry, 1); |
| 298 | |
| 299 | if ((bitmap_entry >> (pageentry_index % 8)) & 1) |
| 300 | return -1; // not allocated |
| 301 | #endif |
| 302 | #endif |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 303 | |
aliguori | b71d1c2 | 2009-01-26 20:26:58 +0000 | [diff] [blame] | 304 | return block_offset; |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 305 | } |
| 306 | |
aliguori | 15d35bc | 2009-01-26 20:27:02 +0000 | [diff] [blame] | 307 | /* |
| 308 | * Writes the footer to the end of the image file. This is needed when the |
| 309 | * file grows as it overwrites the old footer |
| 310 | * |
| 311 | * Returns 0 on success and < 0 on error |
| 312 | */ |
| 313 | static int rewrite_footer(BlockDriverState* bs) |
| 314 | { |
| 315 | int ret; |
| 316 | BDRVVPCState *s = bs->opaque; |
| 317 | int64_t offset = s->free_data_block_offset; |
| 318 | |
| 319 | ret = bdrv_pwrite(s->hd, offset, s->footer_buf, HEADER_SIZE); |
| 320 | if (ret < 0) |
| 321 | return ret; |
| 322 | |
| 323 | return 0; |
| 324 | } |
| 325 | |
| 326 | /* |
| 327 | * Allocates a new block. This involves writing a new footer and updating |
| 328 | * the Block Allocation Table to use the space at the old end of the image |
| 329 | * file (overwriting the old footer) |
| 330 | * |
| 331 | * Returns the sectors' offset in the image file on success and < 0 on error |
| 332 | */ |
| 333 | static int64_t alloc_block(BlockDriverState* bs, int64_t sector_num) |
| 334 | { |
| 335 | BDRVVPCState *s = bs->opaque; |
| 336 | int64_t bat_offset; |
| 337 | uint32_t index, bat_value; |
| 338 | int ret; |
| 339 | uint8_t bitmap[s->bitmap_size]; |
| 340 | |
| 341 | // Check if sector_num is valid |
| 342 | if ((sector_num < 0) || (sector_num > bs->total_sectors)) |
| 343 | return -1; |
| 344 | |
| 345 | // Write entry into in-memory BAT |
| 346 | index = (sector_num * 512) / s->block_size; |
| 347 | if (s->pagetable[index] != 0xFFFFFFFF) |
| 348 | return -1; |
| 349 | |
| 350 | s->pagetable[index] = s->free_data_block_offset / 512; |
| 351 | |
| 352 | // Initialize the block's bitmap |
| 353 | memset(bitmap, 0xff, s->bitmap_size); |
| 354 | bdrv_pwrite(s->hd, s->free_data_block_offset, bitmap, s->bitmap_size); |
| 355 | |
| 356 | // Write new footer (the old one will be overwritten) |
| 357 | s->free_data_block_offset += s->block_size + s->bitmap_size; |
| 358 | ret = rewrite_footer(bs); |
| 359 | if (ret < 0) |
| 360 | goto fail; |
| 361 | |
| 362 | // Write BAT entry to disk |
| 363 | bat_offset = s->bat_offset + (4 * index); |
| 364 | bat_value = be32_to_cpu(s->pagetable[index]); |
| 365 | ret = bdrv_pwrite(s->hd, bat_offset, &bat_value, 4); |
| 366 | if (ret < 0) |
| 367 | goto fail; |
| 368 | |
| 369 | return get_sector_offset(bs, sector_num, 0); |
| 370 | |
| 371 | fail: |
| 372 | s->free_data_block_offset -= (s->block_size + s->bitmap_size); |
| 373 | return -1; |
| 374 | } |
| 375 | |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 376 | static int vpc_read(BlockDriverState *bs, int64_t sector_num, |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 377 | uint8_t *buf, int nb_sectors) |
| 378 | { |
| 379 | BDRVVPCState *s = bs->opaque; |
| 380 | int ret; |
aliguori | b71d1c2 | 2009-01-26 20:26:58 +0000 | [diff] [blame] | 381 | int64_t offset; |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 382 | |
| 383 | while (nb_sectors > 0) { |
aliguori | 15d35bc | 2009-01-26 20:27:02 +0000 | [diff] [blame] | 384 | offset = get_sector_offset(bs, sector_num, 0); |
aliguori | b71d1c2 | 2009-01-26 20:26:58 +0000 | [diff] [blame] | 385 | |
| 386 | if (offset == -1) { |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 387 | memset(buf, 0, 512); |
aliguori | b71d1c2 | 2009-01-26 20:26:58 +0000 | [diff] [blame] | 388 | } else { |
| 389 | ret = bdrv_pread(s->hd, offset, buf, 512); |
| 390 | if (ret != 512) |
| 391 | return -1; |
| 392 | } |
| 393 | |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 394 | nb_sectors--; |
| 395 | sector_num++; |
| 396 | buf += 512; |
| 397 | } |
| 398 | return 0; |
| 399 | } |
| 400 | |
aliguori | 15d35bc | 2009-01-26 20:27:02 +0000 | [diff] [blame] | 401 | static int vpc_write(BlockDriverState *bs, int64_t sector_num, |
| 402 | const uint8_t *buf, int nb_sectors) |
| 403 | { |
| 404 | BDRVVPCState *s = bs->opaque; |
| 405 | int64_t offset; |
| 406 | int ret; |
| 407 | |
| 408 | while (nb_sectors > 0) { |
| 409 | offset = get_sector_offset(bs, sector_num, 1); |
| 410 | |
| 411 | if (offset == -1) { |
| 412 | offset = alloc_block(bs, sector_num); |
| 413 | if (offset < 0) |
| 414 | return -1; |
| 415 | } |
| 416 | |
| 417 | ret = bdrv_pwrite(s->hd, offset, buf, 512); |
| 418 | if (ret != 512) |
| 419 | return -1; |
| 420 | |
| 421 | nb_sectors--; |
| 422 | sector_num++; |
| 423 | buf += 512; |
| 424 | } |
| 425 | |
| 426 | return 0; |
| 427 | } |
| 428 | |
aliguori | 57c7d9e | 2009-01-26 20:27:06 +0000 | [diff] [blame] | 429 | |
| 430 | /* |
| 431 | * Calculates the number of cylinders, heads and sectors per cylinder |
| 432 | * based on a given number of sectors. This is the algorithm described |
| 433 | * in the VHD specification. |
| 434 | * |
| 435 | * Note that the geometry doesn't always exactly match total_sectors but |
| 436 | * may round it down. |
aurel32 | 6e9ea0c | 2009-04-15 14:42:46 +0000 | [diff] [blame] | 437 | * |
| 438 | * Returns 0 on success, -EFBIG if the size is larger than 127 GB |
aliguori | 57c7d9e | 2009-01-26 20:27:06 +0000 | [diff] [blame] | 439 | */ |
aurel32 | 6e9ea0c | 2009-04-15 14:42:46 +0000 | [diff] [blame] | 440 | static int calculate_geometry(int64_t total_sectors, uint16_t* cyls, |
aliguori | 57c7d9e | 2009-01-26 20:27:06 +0000 | [diff] [blame] | 441 | uint8_t* heads, uint8_t* secs_per_cyl) |
| 442 | { |
| 443 | uint32_t cyls_times_heads; |
| 444 | |
| 445 | if (total_sectors > 65535 * 16 * 255) |
aurel32 | 6e9ea0c | 2009-04-15 14:42:46 +0000 | [diff] [blame] | 446 | return -EFBIG; |
aliguori | 57c7d9e | 2009-01-26 20:27:06 +0000 | [diff] [blame] | 447 | |
| 448 | if (total_sectors > 65535 * 16 * 63) { |
| 449 | *secs_per_cyl = 255; |
| 450 | *heads = 16; |
| 451 | cyls_times_heads = total_sectors / *secs_per_cyl; |
| 452 | } else { |
| 453 | *secs_per_cyl = 17; |
| 454 | cyls_times_heads = total_sectors / *secs_per_cyl; |
| 455 | *heads = (cyls_times_heads + 1023) / 1024; |
| 456 | |
| 457 | if (*heads < 4) |
| 458 | *heads = 4; |
| 459 | |
| 460 | if (cyls_times_heads >= (*heads * 1024) || *heads > 16) { |
| 461 | *secs_per_cyl = 31; |
| 462 | *heads = 16; |
| 463 | cyls_times_heads = total_sectors / *secs_per_cyl; |
| 464 | } |
| 465 | |
| 466 | if (cyls_times_heads >= (*heads * 1024)) { |
| 467 | *secs_per_cyl = 63; |
| 468 | *heads = 16; |
| 469 | cyls_times_heads = total_sectors / *secs_per_cyl; |
| 470 | } |
| 471 | } |
| 472 | |
| 473 | // Note: Rounding up deviates from the Virtual PC behaviour |
| 474 | // However, we need this to avoid truncating images in qemu-img convert |
| 475 | *cyls = (cyls_times_heads + *heads - 1) / *heads; |
aurel32 | 6e9ea0c | 2009-04-15 14:42:46 +0000 | [diff] [blame] | 476 | |
| 477 | return 0; |
aliguori | 57c7d9e | 2009-01-26 20:27:06 +0000 | [diff] [blame] | 478 | } |
| 479 | |
Kevin Wolf | 0e7e198 | 2009-05-18 16:42:10 +0200 | [diff] [blame] | 480 | static int vpc_create(const char *filename, QEMUOptionParameter *options) |
aliguori | 57c7d9e | 2009-01-26 20:27:06 +0000 | [diff] [blame] | 481 | { |
| 482 | uint8_t buf[1024]; |
| 483 | struct vhd_footer* footer = (struct vhd_footer*) buf; |
| 484 | struct vhd_dyndisk_header* dyndisk_header = |
| 485 | (struct vhd_dyndisk_header*) buf; |
| 486 | int fd, i; |
| 487 | uint16_t cyls; |
| 488 | uint8_t heads; |
| 489 | uint8_t secs_per_cyl; |
| 490 | size_t block_size, num_bat_entries; |
Kevin Wolf | 0e7e198 | 2009-05-18 16:42:10 +0200 | [diff] [blame] | 491 | int64_t total_sectors = 0; |
aliguori | 57c7d9e | 2009-01-26 20:27:06 +0000 | [diff] [blame] | 492 | |
Kevin Wolf | 0e7e198 | 2009-05-18 16:42:10 +0200 | [diff] [blame] | 493 | // Read out options |
| 494 | while (options && options->name) { |
| 495 | if (!strcmp(options->name, "size")) { |
| 496 | total_sectors = options->value.n / 512; |
| 497 | } |
| 498 | options++; |
| 499 | } |
aliguori | 57c7d9e | 2009-01-26 20:27:06 +0000 | [diff] [blame] | 500 | |
Kevin Wolf | 0e7e198 | 2009-05-18 16:42:10 +0200 | [diff] [blame] | 501 | // Create the file |
aliguori | 57c7d9e | 2009-01-26 20:27:06 +0000 | [diff] [blame] | 502 | fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, 0644); |
| 503 | if (fd < 0) |
| 504 | return -EIO; |
| 505 | |
| 506 | // Calculate matching total_size and geometry |
aurel32 | 6e9ea0c | 2009-04-15 14:42:46 +0000 | [diff] [blame] | 507 | if (calculate_geometry(total_sectors, &cyls, &heads, &secs_per_cyl)) |
| 508 | return -EFBIG; |
aliguori | 57c7d9e | 2009-01-26 20:27:06 +0000 | [diff] [blame] | 509 | total_sectors = (int64_t) cyls * heads * secs_per_cyl; |
| 510 | |
| 511 | // Prepare the Hard Disk Footer |
| 512 | memset(buf, 0, 1024); |
| 513 | |
Nathan Froyd | 5ec4d68 | 2009-08-11 12:47:59 -0700 | [diff] [blame] | 514 | memcpy(footer->creator, "conectix", 8); |
aliguori | 57c7d9e | 2009-01-26 20:27:06 +0000 | [diff] [blame] | 515 | // TODO Check if "qemu" creator_app is ok for VPC |
Nathan Froyd | 5ec4d68 | 2009-08-11 12:47:59 -0700 | [diff] [blame] | 516 | memcpy(footer->creator_app, "qemu", 4); |
| 517 | memcpy(footer->creator_os, "Wi2k", 4); |
aliguori | 57c7d9e | 2009-01-26 20:27:06 +0000 | [diff] [blame] | 518 | |
| 519 | footer->features = be32_to_cpu(0x02); |
| 520 | footer->version = be32_to_cpu(0x00010000); |
| 521 | footer->data_offset = be64_to_cpu(HEADER_SIZE); |
| 522 | footer->timestamp = be32_to_cpu(time(NULL) - VHD_TIMESTAMP_BASE); |
| 523 | |
| 524 | // Version of Virtual PC 2007 |
| 525 | footer->major = be16_to_cpu(0x0005); |
| 526 | footer->minor =be16_to_cpu(0x0003); |
| 527 | |
| 528 | footer->orig_size = be64_to_cpu(total_sectors * 512); |
| 529 | footer->size = be64_to_cpu(total_sectors * 512); |
| 530 | |
| 531 | footer->cyls = be16_to_cpu(cyls); |
| 532 | footer->heads = heads; |
| 533 | footer->secs_per_cyl = secs_per_cyl; |
| 534 | |
| 535 | footer->type = be32_to_cpu(VHD_DYNAMIC); |
| 536 | |
| 537 | // TODO uuid is missing |
| 538 | |
| 539 | footer->checksum = be32_to_cpu(vpc_checksum(buf, HEADER_SIZE)); |
| 540 | |
| 541 | // Write the footer (twice: at the beginning and at the end) |
| 542 | block_size = 0x200000; |
| 543 | num_bat_entries = (total_sectors + block_size / 512) / (block_size / 512); |
| 544 | |
| 545 | if (write(fd, buf, HEADER_SIZE) != HEADER_SIZE) |
| 546 | return -EIO; |
| 547 | |
| 548 | if (lseek(fd, 1536 + ((num_bat_entries * 4 + 511) & ~511), SEEK_SET) < 0) |
| 549 | return -EIO; |
| 550 | if (write(fd, buf, HEADER_SIZE) != HEADER_SIZE) |
| 551 | return -EIO; |
| 552 | |
| 553 | // Write the initial BAT |
| 554 | if (lseek(fd, 3 * 512, SEEK_SET) < 0) |
| 555 | return -EIO; |
| 556 | |
| 557 | memset(buf, 0xFF, 512); |
| 558 | for (i = 0; i < (num_bat_entries * 4 + 511) / 512; i++) |
| 559 | if (write(fd, buf, 512) != 512) |
| 560 | return -EIO; |
| 561 | |
| 562 | |
| 563 | // Prepare the Dynamic Disk Header |
| 564 | memset(buf, 0, 1024); |
| 565 | |
Nathan Froyd | 5ec4d68 | 2009-08-11 12:47:59 -0700 | [diff] [blame] | 566 | memcpy(dyndisk_header->magic, "cxsparse", 8); |
aliguori | 57c7d9e | 2009-01-26 20:27:06 +0000 | [diff] [blame] | 567 | |
| 568 | dyndisk_header->data_offset = be64_to_cpu(0xFFFFFFFF); |
| 569 | dyndisk_header->table_offset = be64_to_cpu(3 * 512); |
| 570 | dyndisk_header->version = be32_to_cpu(0x00010000); |
| 571 | dyndisk_header->block_size = be32_to_cpu(block_size); |
| 572 | dyndisk_header->max_table_entries = be32_to_cpu(num_bat_entries); |
| 573 | |
| 574 | dyndisk_header->checksum = be32_to_cpu(vpc_checksum(buf, 1024)); |
| 575 | |
| 576 | // Write the header |
| 577 | if (lseek(fd, 512, SEEK_SET) < 0) |
| 578 | return -EIO; |
| 579 | if (write(fd, buf, 1024) != 1024) |
| 580 | return -EIO; |
| 581 | |
| 582 | close(fd); |
| 583 | return 0; |
| 584 | } |
| 585 | |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 586 | static void vpc_close(BlockDriverState *bs) |
| 587 | { |
| 588 | BDRVVPCState *s = bs->opaque; |
| 589 | qemu_free(s->pagetable); |
| 590 | #ifdef CACHE |
| 591 | qemu_free(s->pageentry_u8); |
| 592 | #endif |
aliguori | b71d1c2 | 2009-01-26 20:26:58 +0000 | [diff] [blame] | 593 | bdrv_delete(s->hd); |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 594 | } |
| 595 | |
Kevin Wolf | 0e7e198 | 2009-05-18 16:42:10 +0200 | [diff] [blame] | 596 | static QEMUOptionParameter vpc_create_options[] = { |
Kevin Wolf | db08adf | 2009-06-04 15:39:38 +0200 | [diff] [blame] | 597 | { |
| 598 | .name = BLOCK_OPT_SIZE, |
| 599 | .type = OPT_SIZE, |
| 600 | .help = "Virtual disk size" |
| 601 | }, |
Kevin Wolf | 0e7e198 | 2009-05-18 16:42:10 +0200 | [diff] [blame] | 602 | { NULL } |
| 603 | }; |
| 604 | |
Anthony Liguori | 5efa9d5 | 2009-05-09 17:03:42 -0500 | [diff] [blame] | 605 | static BlockDriver bdrv_vpc = { |
aurel32 | e60f469 | 2009-03-07 22:00:29 +0000 | [diff] [blame] | 606 | .format_name = "vpc", |
| 607 | .instance_size = sizeof(BDRVVPCState), |
| 608 | .bdrv_probe = vpc_probe, |
| 609 | .bdrv_open = vpc_open, |
| 610 | .bdrv_read = vpc_read, |
| 611 | .bdrv_write = vpc_write, |
| 612 | .bdrv_close = vpc_close, |
| 613 | .bdrv_create = vpc_create, |
Kevin Wolf | 0e7e198 | 2009-05-18 16:42:10 +0200 | [diff] [blame] | 614 | |
| 615 | .create_options = vpc_create_options, |
bellard | 6a0f9e8 | 2005-04-27 20:17:58 +0000 | [diff] [blame] | 616 | }; |
Anthony Liguori | 5efa9d5 | 2009-05-09 17:03:42 -0500 | [diff] [blame] | 617 | |
| 618 | static void bdrv_vpc_init(void) |
| 619 | { |
| 620 | bdrv_register(&bdrv_vpc); |
| 621 | } |
| 622 | |
| 623 | block_init(bdrv_vpc_init); |