1019d6b8fSAnthony Liguori /* 2019d6b8fSAnthony Liguori * Block driver for Conectix/Microsoft Virtual PC images 3019d6b8fSAnthony Liguori * 4019d6b8fSAnthony Liguori * Copyright (c) 2005 Alex Beregszaszi 5019d6b8fSAnthony Liguori * Copyright (c) 2009 Kevin Wolf <kwolf@suse.de> 6019d6b8fSAnthony Liguori * 7019d6b8fSAnthony Liguori * Permission is hereby granted, free of charge, to any person obtaining a copy 8019d6b8fSAnthony Liguori * of this software and associated documentation files (the "Software"), to deal 9019d6b8fSAnthony Liguori * in the Software without restriction, including without limitation the rights 10019d6b8fSAnthony Liguori * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 11019d6b8fSAnthony Liguori * copies of the Software, and to permit persons to whom the Software is 12019d6b8fSAnthony Liguori * furnished to do so, subject to the following conditions: 13019d6b8fSAnthony Liguori * 14019d6b8fSAnthony Liguori * The above copyright notice and this permission notice shall be included in 15019d6b8fSAnthony Liguori * all copies or substantial portions of the Software. 16019d6b8fSAnthony Liguori * 17019d6b8fSAnthony Liguori * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 18019d6b8fSAnthony Liguori * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 19019d6b8fSAnthony Liguori * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 20019d6b8fSAnthony Liguori * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 21019d6b8fSAnthony Liguori * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 22019d6b8fSAnthony Liguori * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 23019d6b8fSAnthony Liguori * THE SOFTWARE. 24019d6b8fSAnthony Liguori */ 25019d6b8fSAnthony Liguori #include "qemu-common.h" 26019d6b8fSAnthony Liguori #include "block_int.h" 27019d6b8fSAnthony Liguori #include "module.h" 28019d6b8fSAnthony Liguori 29019d6b8fSAnthony Liguori /**************************************************************/ 30019d6b8fSAnthony Liguori 31019d6b8fSAnthony Liguori #define HEADER_SIZE 512 32019d6b8fSAnthony Liguori 33019d6b8fSAnthony Liguori //#define CACHE 34019d6b8fSAnthony Liguori 35019d6b8fSAnthony Liguori enum vhd_type { 36019d6b8fSAnthony Liguori VHD_FIXED = 2, 37019d6b8fSAnthony Liguori VHD_DYNAMIC = 3, 38019d6b8fSAnthony Liguori VHD_DIFFERENCING = 4, 39019d6b8fSAnthony Liguori }; 40019d6b8fSAnthony Liguori 41019d6b8fSAnthony Liguori // Seconds since Jan 1, 2000 0:00:00 (UTC) 42019d6b8fSAnthony Liguori #define VHD_TIMESTAMP_BASE 946684800 43019d6b8fSAnthony Liguori 44019d6b8fSAnthony Liguori // always big-endian 45019d6b8fSAnthony Liguori struct vhd_footer { 46019d6b8fSAnthony Liguori char creator[8]; // "conectix" 47019d6b8fSAnthony Liguori uint32_t features; 48019d6b8fSAnthony Liguori uint32_t version; 49019d6b8fSAnthony Liguori 50019d6b8fSAnthony Liguori // Offset of next header structure, 0xFFFFFFFF if none 51019d6b8fSAnthony Liguori uint64_t data_offset; 52019d6b8fSAnthony Liguori 53019d6b8fSAnthony Liguori // Seconds since Jan 1, 2000 0:00:00 (UTC) 54019d6b8fSAnthony Liguori uint32_t timestamp; 55019d6b8fSAnthony Liguori 56019d6b8fSAnthony Liguori char creator_app[4]; // "vpc " 57019d6b8fSAnthony Liguori uint16_t major; 58019d6b8fSAnthony Liguori uint16_t minor; 59019d6b8fSAnthony Liguori char creator_os[4]; // "Wi2k" 60019d6b8fSAnthony Liguori 61019d6b8fSAnthony Liguori uint64_t orig_size; 62019d6b8fSAnthony Liguori uint64_t size; 63019d6b8fSAnthony Liguori 64019d6b8fSAnthony Liguori uint16_t cyls; 65019d6b8fSAnthony Liguori uint8_t heads; 66019d6b8fSAnthony Liguori uint8_t secs_per_cyl; 67019d6b8fSAnthony Liguori 68019d6b8fSAnthony Liguori uint32_t type; 69019d6b8fSAnthony Liguori 70019d6b8fSAnthony Liguori // Checksum of the Hard Disk Footer ("one's complement of the sum of all 71019d6b8fSAnthony Liguori // the bytes in the footer without the checksum field") 72019d6b8fSAnthony Liguori uint32_t checksum; 73019d6b8fSAnthony Liguori 74019d6b8fSAnthony Liguori // UUID used to identify a parent hard disk (backing file) 75019d6b8fSAnthony Liguori uint8_t uuid[16]; 76019d6b8fSAnthony Liguori 77019d6b8fSAnthony Liguori uint8_t in_saved_state; 78019d6b8fSAnthony Liguori }; 79019d6b8fSAnthony Liguori 80019d6b8fSAnthony Liguori struct vhd_dyndisk_header { 81019d6b8fSAnthony Liguori char magic[8]; // "cxsparse" 82019d6b8fSAnthony Liguori 83019d6b8fSAnthony Liguori // Offset of next header structure, 0xFFFFFFFF if none 84019d6b8fSAnthony Liguori uint64_t data_offset; 85019d6b8fSAnthony Liguori 86019d6b8fSAnthony Liguori // Offset of the Block Allocation Table (BAT) 87019d6b8fSAnthony Liguori uint64_t table_offset; 88019d6b8fSAnthony Liguori 89019d6b8fSAnthony Liguori uint32_t version; 90019d6b8fSAnthony Liguori uint32_t max_table_entries; // 32bit/entry 91019d6b8fSAnthony Liguori 92019d6b8fSAnthony Liguori // 2 MB by default, must be a power of two 93019d6b8fSAnthony Liguori uint32_t block_size; 94019d6b8fSAnthony Liguori 95019d6b8fSAnthony Liguori uint32_t checksum; 96019d6b8fSAnthony Liguori uint8_t parent_uuid[16]; 97019d6b8fSAnthony Liguori uint32_t parent_timestamp; 98019d6b8fSAnthony Liguori uint32_t reserved; 99019d6b8fSAnthony Liguori 100019d6b8fSAnthony Liguori // Backing file name (in UTF-16) 101019d6b8fSAnthony Liguori uint8_t parent_name[512]; 102019d6b8fSAnthony Liguori 103019d6b8fSAnthony Liguori struct { 104019d6b8fSAnthony Liguori uint32_t platform; 105019d6b8fSAnthony Liguori uint32_t data_space; 106019d6b8fSAnthony Liguori uint32_t data_length; 107019d6b8fSAnthony Liguori uint32_t reserved; 108019d6b8fSAnthony Liguori uint64_t data_offset; 109019d6b8fSAnthony Liguori } parent_locator[8]; 110019d6b8fSAnthony Liguori }; 111019d6b8fSAnthony Liguori 112019d6b8fSAnthony Liguori typedef struct BDRVVPCState { 113019d6b8fSAnthony Liguori BlockDriverState *hd; 114019d6b8fSAnthony Liguori 115019d6b8fSAnthony Liguori uint8_t footer_buf[HEADER_SIZE]; 116019d6b8fSAnthony Liguori uint64_t free_data_block_offset; 117019d6b8fSAnthony Liguori int max_table_entries; 118019d6b8fSAnthony Liguori uint32_t *pagetable; 119019d6b8fSAnthony Liguori uint64_t bat_offset; 120019d6b8fSAnthony Liguori uint64_t last_bitmap_offset; 121019d6b8fSAnthony Liguori 122019d6b8fSAnthony Liguori uint32_t block_size; 123019d6b8fSAnthony Liguori uint32_t bitmap_size; 124019d6b8fSAnthony Liguori 125019d6b8fSAnthony Liguori #ifdef CACHE 126019d6b8fSAnthony Liguori uint8_t *pageentry_u8; 127019d6b8fSAnthony Liguori uint32_t *pageentry_u32; 128019d6b8fSAnthony Liguori uint16_t *pageentry_u16; 129019d6b8fSAnthony Liguori 130019d6b8fSAnthony Liguori uint64_t last_bitmap; 131019d6b8fSAnthony Liguori #endif 132019d6b8fSAnthony Liguori } BDRVVPCState; 133019d6b8fSAnthony Liguori 134019d6b8fSAnthony Liguori static uint32_t vpc_checksum(uint8_t* buf, size_t size) 135019d6b8fSAnthony Liguori { 136019d6b8fSAnthony Liguori uint32_t res = 0; 137019d6b8fSAnthony Liguori int i; 138019d6b8fSAnthony Liguori 139019d6b8fSAnthony Liguori for (i = 0; i < size; i++) 140019d6b8fSAnthony Liguori res += buf[i]; 141019d6b8fSAnthony Liguori 142019d6b8fSAnthony Liguori return ~res; 143019d6b8fSAnthony Liguori } 144019d6b8fSAnthony Liguori 145019d6b8fSAnthony Liguori 146019d6b8fSAnthony Liguori static int vpc_probe(const uint8_t *buf, int buf_size, const char *filename) 147019d6b8fSAnthony Liguori { 148019d6b8fSAnthony Liguori if (buf_size >= 8 && !strncmp((char *)buf, "conectix", 8)) 149019d6b8fSAnthony Liguori return 100; 150019d6b8fSAnthony Liguori return 0; 151019d6b8fSAnthony Liguori } 152019d6b8fSAnthony Liguori 153019d6b8fSAnthony Liguori static int vpc_open(BlockDriverState *bs, const char *filename, int flags) 154019d6b8fSAnthony Liguori { 155019d6b8fSAnthony Liguori BDRVVPCState *s = bs->opaque; 156019d6b8fSAnthony Liguori int ret, i; 157019d6b8fSAnthony Liguori struct vhd_footer* footer; 158019d6b8fSAnthony Liguori struct vhd_dyndisk_header* dyndisk_header; 159019d6b8fSAnthony Liguori uint8_t buf[HEADER_SIZE]; 160019d6b8fSAnthony Liguori uint32_t checksum; 161019d6b8fSAnthony Liguori 162019d6b8fSAnthony Liguori ret = bdrv_file_open(&s->hd, filename, flags); 163019d6b8fSAnthony Liguori if (ret < 0) 164019d6b8fSAnthony Liguori return ret; 165019d6b8fSAnthony Liguori 166019d6b8fSAnthony Liguori if (bdrv_pread(s->hd, 0, s->footer_buf, HEADER_SIZE) != HEADER_SIZE) 167019d6b8fSAnthony Liguori goto fail; 168019d6b8fSAnthony Liguori 169019d6b8fSAnthony Liguori footer = (struct vhd_footer*) s->footer_buf; 170019d6b8fSAnthony Liguori if (strncmp(footer->creator, "conectix", 8)) 171019d6b8fSAnthony Liguori goto fail; 172019d6b8fSAnthony Liguori 173019d6b8fSAnthony Liguori checksum = be32_to_cpu(footer->checksum); 174019d6b8fSAnthony Liguori footer->checksum = 0; 175019d6b8fSAnthony Liguori if (vpc_checksum(s->footer_buf, HEADER_SIZE) != checksum) 176019d6b8fSAnthony Liguori fprintf(stderr, "block-vpc: The header checksum of '%s' is " 177019d6b8fSAnthony Liguori "incorrect.\n", filename); 178019d6b8fSAnthony Liguori 179019d6b8fSAnthony Liguori // The visible size of a image in Virtual PC depends on the geometry 180019d6b8fSAnthony Liguori // rather than on the size stored in the footer (the size in the footer 181019d6b8fSAnthony Liguori // is too large usually) 182019d6b8fSAnthony Liguori bs->total_sectors = (int64_t) 183019d6b8fSAnthony Liguori be16_to_cpu(footer->cyls) * footer->heads * footer->secs_per_cyl; 184019d6b8fSAnthony Liguori 185019d6b8fSAnthony Liguori if (bdrv_pread(s->hd, be64_to_cpu(footer->data_offset), buf, HEADER_SIZE) 186019d6b8fSAnthony Liguori != HEADER_SIZE) 187019d6b8fSAnthony Liguori goto fail; 188019d6b8fSAnthony Liguori 189019d6b8fSAnthony Liguori dyndisk_header = (struct vhd_dyndisk_header*) buf; 190019d6b8fSAnthony Liguori 191019d6b8fSAnthony Liguori if (strncmp(dyndisk_header->magic, "cxsparse", 8)) 192019d6b8fSAnthony Liguori goto fail; 193019d6b8fSAnthony Liguori 194019d6b8fSAnthony Liguori 195019d6b8fSAnthony Liguori s->block_size = be32_to_cpu(dyndisk_header->block_size); 196019d6b8fSAnthony Liguori s->bitmap_size = ((s->block_size / (8 * 512)) + 511) & ~511; 197019d6b8fSAnthony Liguori 198019d6b8fSAnthony Liguori s->max_table_entries = be32_to_cpu(dyndisk_header->max_table_entries); 199019d6b8fSAnthony Liguori s->pagetable = qemu_malloc(s->max_table_entries * 4); 200019d6b8fSAnthony Liguori 201019d6b8fSAnthony Liguori s->bat_offset = be64_to_cpu(dyndisk_header->table_offset); 202019d6b8fSAnthony Liguori if (bdrv_pread(s->hd, s->bat_offset, s->pagetable, 203019d6b8fSAnthony Liguori s->max_table_entries * 4) != s->max_table_entries * 4) 204019d6b8fSAnthony Liguori goto fail; 205019d6b8fSAnthony Liguori 206019d6b8fSAnthony Liguori s->free_data_block_offset = 207019d6b8fSAnthony Liguori (s->bat_offset + (s->max_table_entries * 4) + 511) & ~511; 208019d6b8fSAnthony Liguori 209019d6b8fSAnthony Liguori for (i = 0; i < s->max_table_entries; i++) { 210019d6b8fSAnthony Liguori be32_to_cpus(&s->pagetable[i]); 211019d6b8fSAnthony Liguori if (s->pagetable[i] != 0xFFFFFFFF) { 212019d6b8fSAnthony Liguori int64_t next = (512 * (int64_t) s->pagetable[i]) + 213019d6b8fSAnthony Liguori s->bitmap_size + s->block_size; 214019d6b8fSAnthony Liguori 215019d6b8fSAnthony Liguori if (next> s->free_data_block_offset) 216019d6b8fSAnthony Liguori s->free_data_block_offset = next; 217019d6b8fSAnthony Liguori } 218019d6b8fSAnthony Liguori } 219019d6b8fSAnthony Liguori 220019d6b8fSAnthony Liguori s->last_bitmap_offset = (int64_t) -1; 221019d6b8fSAnthony Liguori 222019d6b8fSAnthony Liguori #ifdef CACHE 223019d6b8fSAnthony Liguori s->pageentry_u8 = qemu_malloc(512); 224019d6b8fSAnthony Liguori s->pageentry_u32 = s->pageentry_u8; 225019d6b8fSAnthony Liguori s->pageentry_u16 = s->pageentry_u8; 226019d6b8fSAnthony Liguori s->last_pagetable = -1; 227019d6b8fSAnthony Liguori #endif 228019d6b8fSAnthony Liguori 229019d6b8fSAnthony Liguori return 0; 230019d6b8fSAnthony Liguori fail: 231019d6b8fSAnthony Liguori bdrv_delete(s->hd); 232019d6b8fSAnthony Liguori return -1; 233019d6b8fSAnthony Liguori } 234019d6b8fSAnthony Liguori 235019d6b8fSAnthony Liguori /* 236019d6b8fSAnthony Liguori * Returns the absolute byte offset of the given sector in the image file. 237019d6b8fSAnthony Liguori * If the sector is not allocated, -1 is returned instead. 238019d6b8fSAnthony Liguori * 239019d6b8fSAnthony Liguori * The parameter write must be 1 if the offset will be used for a write 240019d6b8fSAnthony Liguori * operation (the block bitmaps is updated then), 0 otherwise. 241019d6b8fSAnthony Liguori */ 242019d6b8fSAnthony Liguori static inline int64_t get_sector_offset(BlockDriverState *bs, 243019d6b8fSAnthony Liguori int64_t sector_num, int write) 244019d6b8fSAnthony Liguori { 245019d6b8fSAnthony Liguori BDRVVPCState *s = bs->opaque; 246019d6b8fSAnthony Liguori uint64_t offset = sector_num * 512; 247019d6b8fSAnthony Liguori uint64_t bitmap_offset, block_offset; 248019d6b8fSAnthony Liguori uint32_t pagetable_index, pageentry_index; 249019d6b8fSAnthony Liguori 250019d6b8fSAnthony Liguori pagetable_index = offset / s->block_size; 251019d6b8fSAnthony Liguori pageentry_index = (offset % s->block_size) / 512; 252019d6b8fSAnthony Liguori 253019d6b8fSAnthony Liguori if (pagetable_index >= s->max_table_entries || s->pagetable[pagetable_index] == 0xffffffff) 254019d6b8fSAnthony Liguori return -1; // not allocated 255019d6b8fSAnthony Liguori 256019d6b8fSAnthony Liguori bitmap_offset = 512 * (uint64_t) s->pagetable[pagetable_index]; 257019d6b8fSAnthony Liguori block_offset = bitmap_offset + s->bitmap_size + (512 * pageentry_index); 258019d6b8fSAnthony Liguori 259019d6b8fSAnthony Liguori // We must ensure that we don't write to any sectors which are marked as 260019d6b8fSAnthony Liguori // unused in the bitmap. We get away with setting all bits in the block 261019d6b8fSAnthony Liguori // bitmap each time we write to a new block. This might cause Virtual PC to 262019d6b8fSAnthony Liguori // miss sparse read optimization, but it's not a problem in terms of 263019d6b8fSAnthony Liguori // correctness. 264019d6b8fSAnthony Liguori if (write && (s->last_bitmap_offset != bitmap_offset)) { 265019d6b8fSAnthony Liguori uint8_t bitmap[s->bitmap_size]; 266019d6b8fSAnthony Liguori 267019d6b8fSAnthony Liguori s->last_bitmap_offset = bitmap_offset; 268019d6b8fSAnthony Liguori memset(bitmap, 0xff, s->bitmap_size); 269019d6b8fSAnthony Liguori bdrv_pwrite(s->hd, bitmap_offset, bitmap, s->bitmap_size); 270019d6b8fSAnthony Liguori } 271019d6b8fSAnthony Liguori 272019d6b8fSAnthony Liguori // printf("sector: %" PRIx64 ", index: %x, offset: %x, bioff: %" PRIx64 ", bloff: %" PRIx64 "\n", 273019d6b8fSAnthony Liguori // sector_num, pagetable_index, pageentry_index, 274019d6b8fSAnthony Liguori // bitmap_offset, block_offset); 275019d6b8fSAnthony Liguori 276019d6b8fSAnthony Liguori // disabled by reason 277019d6b8fSAnthony Liguori #if 0 278019d6b8fSAnthony Liguori #ifdef CACHE 279019d6b8fSAnthony Liguori if (bitmap_offset != s->last_bitmap) 280019d6b8fSAnthony Liguori { 281019d6b8fSAnthony Liguori lseek(s->fd, bitmap_offset, SEEK_SET); 282019d6b8fSAnthony Liguori 283019d6b8fSAnthony Liguori s->last_bitmap = bitmap_offset; 284019d6b8fSAnthony Liguori 285019d6b8fSAnthony Liguori // Scary! Bitmap is stored as big endian 32bit entries, 286019d6b8fSAnthony Liguori // while we used to look it up byte by byte 287019d6b8fSAnthony Liguori read(s->fd, s->pageentry_u8, 512); 288019d6b8fSAnthony Liguori for (i = 0; i < 128; i++) 289019d6b8fSAnthony Liguori be32_to_cpus(&s->pageentry_u32[i]); 290019d6b8fSAnthony Liguori } 291019d6b8fSAnthony Liguori 292019d6b8fSAnthony Liguori if ((s->pageentry_u8[pageentry_index / 8] >> (pageentry_index % 8)) & 1) 293019d6b8fSAnthony Liguori return -1; 294019d6b8fSAnthony Liguori #else 295019d6b8fSAnthony Liguori lseek(s->fd, bitmap_offset + (pageentry_index / 8), SEEK_SET); 296019d6b8fSAnthony Liguori 297019d6b8fSAnthony Liguori read(s->fd, &bitmap_entry, 1); 298019d6b8fSAnthony Liguori 299019d6b8fSAnthony Liguori if ((bitmap_entry >> (pageentry_index % 8)) & 1) 300019d6b8fSAnthony Liguori return -1; // not allocated 301019d6b8fSAnthony Liguori #endif 302019d6b8fSAnthony Liguori #endif 303019d6b8fSAnthony Liguori 304019d6b8fSAnthony Liguori return block_offset; 305019d6b8fSAnthony Liguori } 306019d6b8fSAnthony Liguori 307019d6b8fSAnthony Liguori /* 308019d6b8fSAnthony Liguori * Writes the footer to the end of the image file. This is needed when the 309019d6b8fSAnthony Liguori * file grows as it overwrites the old footer 310019d6b8fSAnthony Liguori * 311019d6b8fSAnthony Liguori * Returns 0 on success and < 0 on error 312019d6b8fSAnthony Liguori */ 313019d6b8fSAnthony Liguori static int rewrite_footer(BlockDriverState* bs) 314019d6b8fSAnthony Liguori { 315019d6b8fSAnthony Liguori int ret; 316019d6b8fSAnthony Liguori BDRVVPCState *s = bs->opaque; 317019d6b8fSAnthony Liguori int64_t offset = s->free_data_block_offset; 318019d6b8fSAnthony Liguori 319019d6b8fSAnthony Liguori ret = bdrv_pwrite(s->hd, offset, s->footer_buf, HEADER_SIZE); 320019d6b8fSAnthony Liguori if (ret < 0) 321019d6b8fSAnthony Liguori return ret; 322019d6b8fSAnthony Liguori 323019d6b8fSAnthony Liguori return 0; 324019d6b8fSAnthony Liguori } 325019d6b8fSAnthony Liguori 326019d6b8fSAnthony Liguori /* 327019d6b8fSAnthony Liguori * Allocates a new block. This involves writing a new footer and updating 328019d6b8fSAnthony Liguori * the Block Allocation Table to use the space at the old end of the image 329019d6b8fSAnthony Liguori * file (overwriting the old footer) 330019d6b8fSAnthony Liguori * 331019d6b8fSAnthony Liguori * Returns the sectors' offset in the image file on success and < 0 on error 332019d6b8fSAnthony Liguori */ 333019d6b8fSAnthony Liguori static int64_t alloc_block(BlockDriverState* bs, int64_t sector_num) 334019d6b8fSAnthony Liguori { 335019d6b8fSAnthony Liguori BDRVVPCState *s = bs->opaque; 336019d6b8fSAnthony Liguori int64_t bat_offset; 337019d6b8fSAnthony Liguori uint32_t index, bat_value; 338019d6b8fSAnthony Liguori int ret; 339019d6b8fSAnthony Liguori uint8_t bitmap[s->bitmap_size]; 340019d6b8fSAnthony Liguori 341019d6b8fSAnthony Liguori // Check if sector_num is valid 342019d6b8fSAnthony Liguori if ((sector_num < 0) || (sector_num > bs->total_sectors)) 343019d6b8fSAnthony Liguori return -1; 344019d6b8fSAnthony Liguori 345019d6b8fSAnthony Liguori // Write entry into in-memory BAT 346019d6b8fSAnthony Liguori index = (sector_num * 512) / s->block_size; 347019d6b8fSAnthony Liguori if (s->pagetable[index] != 0xFFFFFFFF) 348019d6b8fSAnthony Liguori return -1; 349019d6b8fSAnthony Liguori 350019d6b8fSAnthony Liguori s->pagetable[index] = s->free_data_block_offset / 512; 351019d6b8fSAnthony Liguori 352019d6b8fSAnthony Liguori // Initialize the block's bitmap 353019d6b8fSAnthony Liguori memset(bitmap, 0xff, s->bitmap_size); 354019d6b8fSAnthony Liguori bdrv_pwrite(s->hd, s->free_data_block_offset, bitmap, s->bitmap_size); 355019d6b8fSAnthony Liguori 356019d6b8fSAnthony Liguori // Write new footer (the old one will be overwritten) 357019d6b8fSAnthony Liguori s->free_data_block_offset += s->block_size + s->bitmap_size; 358019d6b8fSAnthony Liguori ret = rewrite_footer(bs); 359019d6b8fSAnthony Liguori if (ret < 0) 360019d6b8fSAnthony Liguori goto fail; 361019d6b8fSAnthony Liguori 362019d6b8fSAnthony Liguori // Write BAT entry to disk 363019d6b8fSAnthony Liguori bat_offset = s->bat_offset + (4 * index); 364019d6b8fSAnthony Liguori bat_value = be32_to_cpu(s->pagetable[index]); 365019d6b8fSAnthony Liguori ret = bdrv_pwrite(s->hd, bat_offset, &bat_value, 4); 366019d6b8fSAnthony Liguori if (ret < 0) 367019d6b8fSAnthony Liguori goto fail; 368019d6b8fSAnthony Liguori 369019d6b8fSAnthony Liguori return get_sector_offset(bs, sector_num, 0); 370019d6b8fSAnthony Liguori 371019d6b8fSAnthony Liguori fail: 372019d6b8fSAnthony Liguori s->free_data_block_offset -= (s->block_size + s->bitmap_size); 373019d6b8fSAnthony Liguori return -1; 374019d6b8fSAnthony Liguori } 375019d6b8fSAnthony Liguori 376019d6b8fSAnthony Liguori static int vpc_read(BlockDriverState *bs, int64_t sector_num, 377019d6b8fSAnthony Liguori uint8_t *buf, int nb_sectors) 378019d6b8fSAnthony Liguori { 379019d6b8fSAnthony Liguori BDRVVPCState *s = bs->opaque; 380019d6b8fSAnthony Liguori int ret; 381019d6b8fSAnthony Liguori int64_t offset; 382019d6b8fSAnthony Liguori 383019d6b8fSAnthony Liguori while (nb_sectors > 0) { 384019d6b8fSAnthony Liguori offset = get_sector_offset(bs, sector_num, 0); 385019d6b8fSAnthony Liguori 386019d6b8fSAnthony Liguori if (offset == -1) { 387019d6b8fSAnthony Liguori memset(buf, 0, 512); 388019d6b8fSAnthony Liguori } else { 389019d6b8fSAnthony Liguori ret = bdrv_pread(s->hd, offset, buf, 512); 390019d6b8fSAnthony Liguori if (ret != 512) 391019d6b8fSAnthony Liguori return -1; 392019d6b8fSAnthony Liguori } 393019d6b8fSAnthony Liguori 394019d6b8fSAnthony Liguori nb_sectors--; 395019d6b8fSAnthony Liguori sector_num++; 396019d6b8fSAnthony Liguori buf += 512; 397019d6b8fSAnthony Liguori } 398019d6b8fSAnthony Liguori return 0; 399019d6b8fSAnthony Liguori } 400019d6b8fSAnthony Liguori 401019d6b8fSAnthony Liguori static int vpc_write(BlockDriverState *bs, int64_t sector_num, 402019d6b8fSAnthony Liguori const uint8_t *buf, int nb_sectors) 403019d6b8fSAnthony Liguori { 404019d6b8fSAnthony Liguori BDRVVPCState *s = bs->opaque; 405019d6b8fSAnthony Liguori int64_t offset; 406019d6b8fSAnthony Liguori int ret; 407019d6b8fSAnthony Liguori 408019d6b8fSAnthony Liguori while (nb_sectors > 0) { 409019d6b8fSAnthony Liguori offset = get_sector_offset(bs, sector_num, 1); 410019d6b8fSAnthony Liguori 411019d6b8fSAnthony Liguori if (offset == -1) { 412019d6b8fSAnthony Liguori offset = alloc_block(bs, sector_num); 413019d6b8fSAnthony Liguori if (offset < 0) 414019d6b8fSAnthony Liguori return -1; 415019d6b8fSAnthony Liguori } 416019d6b8fSAnthony Liguori 417019d6b8fSAnthony Liguori ret = bdrv_pwrite(s->hd, offset, buf, 512); 418019d6b8fSAnthony Liguori if (ret != 512) 419019d6b8fSAnthony Liguori return -1; 420019d6b8fSAnthony Liguori 421019d6b8fSAnthony Liguori nb_sectors--; 422019d6b8fSAnthony Liguori sector_num++; 423019d6b8fSAnthony Liguori buf += 512; 424019d6b8fSAnthony Liguori } 425019d6b8fSAnthony Liguori 426019d6b8fSAnthony Liguori return 0; 427019d6b8fSAnthony Liguori } 428019d6b8fSAnthony Liguori 429019d6b8fSAnthony Liguori 430019d6b8fSAnthony Liguori /* 431019d6b8fSAnthony Liguori * Calculates the number of cylinders, heads and sectors per cylinder 432019d6b8fSAnthony Liguori * based on a given number of sectors. This is the algorithm described 433019d6b8fSAnthony Liguori * in the VHD specification. 434019d6b8fSAnthony Liguori * 435019d6b8fSAnthony Liguori * Note that the geometry doesn't always exactly match total_sectors but 436019d6b8fSAnthony Liguori * may round it down. 437019d6b8fSAnthony Liguori * 438019d6b8fSAnthony Liguori * Returns 0 on success, -EFBIG if the size is larger than 127 GB 439019d6b8fSAnthony Liguori */ 440019d6b8fSAnthony Liguori static int calculate_geometry(int64_t total_sectors, uint16_t* cyls, 441019d6b8fSAnthony Liguori uint8_t* heads, uint8_t* secs_per_cyl) 442019d6b8fSAnthony Liguori { 443019d6b8fSAnthony Liguori uint32_t cyls_times_heads; 444019d6b8fSAnthony Liguori 445019d6b8fSAnthony Liguori if (total_sectors > 65535 * 16 * 255) 446019d6b8fSAnthony Liguori return -EFBIG; 447019d6b8fSAnthony Liguori 448019d6b8fSAnthony Liguori if (total_sectors > 65535 * 16 * 63) { 449019d6b8fSAnthony Liguori *secs_per_cyl = 255; 450019d6b8fSAnthony Liguori *heads = 16; 451019d6b8fSAnthony Liguori cyls_times_heads = total_sectors / *secs_per_cyl; 452019d6b8fSAnthony Liguori } else { 453019d6b8fSAnthony Liguori *secs_per_cyl = 17; 454019d6b8fSAnthony Liguori cyls_times_heads = total_sectors / *secs_per_cyl; 455019d6b8fSAnthony Liguori *heads = (cyls_times_heads + 1023) / 1024; 456019d6b8fSAnthony Liguori 457019d6b8fSAnthony Liguori if (*heads < 4) 458019d6b8fSAnthony Liguori *heads = 4; 459019d6b8fSAnthony Liguori 460019d6b8fSAnthony Liguori if (cyls_times_heads >= (*heads * 1024) || *heads > 16) { 461019d6b8fSAnthony Liguori *secs_per_cyl = 31; 462019d6b8fSAnthony Liguori *heads = 16; 463019d6b8fSAnthony Liguori cyls_times_heads = total_sectors / *secs_per_cyl; 464019d6b8fSAnthony Liguori } 465019d6b8fSAnthony Liguori 466019d6b8fSAnthony Liguori if (cyls_times_heads >= (*heads * 1024)) { 467019d6b8fSAnthony Liguori *secs_per_cyl = 63; 468019d6b8fSAnthony Liguori *heads = 16; 469019d6b8fSAnthony Liguori cyls_times_heads = total_sectors / *secs_per_cyl; 470019d6b8fSAnthony Liguori } 471019d6b8fSAnthony Liguori } 472019d6b8fSAnthony Liguori 473019d6b8fSAnthony Liguori // Note: Rounding up deviates from the Virtual PC behaviour 474019d6b8fSAnthony Liguori // However, we need this to avoid truncating images in qemu-img convert 475019d6b8fSAnthony Liguori *cyls = (cyls_times_heads + *heads - 1) / *heads; 476019d6b8fSAnthony Liguori 477019d6b8fSAnthony Liguori return 0; 478019d6b8fSAnthony Liguori } 479019d6b8fSAnthony Liguori 4800e7e1989SKevin Wolf static int vpc_create(const char *filename, QEMUOptionParameter *options) 481019d6b8fSAnthony Liguori { 482019d6b8fSAnthony Liguori uint8_t buf[1024]; 483019d6b8fSAnthony Liguori struct vhd_footer* footer = (struct vhd_footer*) buf; 484019d6b8fSAnthony Liguori struct vhd_dyndisk_header* dyndisk_header = 485019d6b8fSAnthony Liguori (struct vhd_dyndisk_header*) buf; 486019d6b8fSAnthony Liguori int fd, i; 487019d6b8fSAnthony Liguori uint16_t cyls; 488019d6b8fSAnthony Liguori uint8_t heads; 489019d6b8fSAnthony Liguori uint8_t secs_per_cyl; 490019d6b8fSAnthony Liguori size_t block_size, num_bat_entries; 4910e7e1989SKevin Wolf int64_t total_sectors = 0; 492019d6b8fSAnthony Liguori 4930e7e1989SKevin Wolf // Read out options 4940e7e1989SKevin Wolf while (options && options->name) { 4950e7e1989SKevin Wolf if (!strcmp(options->name, "size")) { 4960e7e1989SKevin Wolf total_sectors = options->value.n / 512; 4970e7e1989SKevin Wolf } 4980e7e1989SKevin Wolf options++; 4990e7e1989SKevin Wolf } 500019d6b8fSAnthony Liguori 5010e7e1989SKevin Wolf // Create the file 502019d6b8fSAnthony Liguori fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, 0644); 503019d6b8fSAnthony Liguori if (fd < 0) 504019d6b8fSAnthony Liguori return -EIO; 505019d6b8fSAnthony Liguori 506019d6b8fSAnthony Liguori // Calculate matching total_size and geometry 507019d6b8fSAnthony Liguori if (calculate_geometry(total_sectors, &cyls, &heads, &secs_per_cyl)) 508019d6b8fSAnthony Liguori return -EFBIG; 509019d6b8fSAnthony Liguori total_sectors = (int64_t) cyls * heads * secs_per_cyl; 510019d6b8fSAnthony Liguori 511019d6b8fSAnthony Liguori // Prepare the Hard Disk Footer 512019d6b8fSAnthony Liguori memset(buf, 0, 1024); 513019d6b8fSAnthony Liguori 514*5ec4d682SNathan Froyd memcpy(footer->creator, "conectix", 8); 515019d6b8fSAnthony Liguori // TODO Check if "qemu" creator_app is ok for VPC 516*5ec4d682SNathan Froyd memcpy(footer->creator_app, "qemu", 4); 517*5ec4d682SNathan Froyd memcpy(footer->creator_os, "Wi2k", 4); 518019d6b8fSAnthony Liguori 519019d6b8fSAnthony Liguori footer->features = be32_to_cpu(0x02); 520019d6b8fSAnthony Liguori footer->version = be32_to_cpu(0x00010000); 521019d6b8fSAnthony Liguori footer->data_offset = be64_to_cpu(HEADER_SIZE); 522019d6b8fSAnthony Liguori footer->timestamp = be32_to_cpu(time(NULL) - VHD_TIMESTAMP_BASE); 523019d6b8fSAnthony Liguori 524019d6b8fSAnthony Liguori // Version of Virtual PC 2007 525019d6b8fSAnthony Liguori footer->major = be16_to_cpu(0x0005); 526019d6b8fSAnthony Liguori footer->minor =be16_to_cpu(0x0003); 527019d6b8fSAnthony Liguori 528019d6b8fSAnthony Liguori footer->orig_size = be64_to_cpu(total_sectors * 512); 529019d6b8fSAnthony Liguori footer->size = be64_to_cpu(total_sectors * 512); 530019d6b8fSAnthony Liguori 531019d6b8fSAnthony Liguori footer->cyls = be16_to_cpu(cyls); 532019d6b8fSAnthony Liguori footer->heads = heads; 533019d6b8fSAnthony Liguori footer->secs_per_cyl = secs_per_cyl; 534019d6b8fSAnthony Liguori 535019d6b8fSAnthony Liguori footer->type = be32_to_cpu(VHD_DYNAMIC); 536019d6b8fSAnthony Liguori 537019d6b8fSAnthony Liguori // TODO uuid is missing 538019d6b8fSAnthony Liguori 539019d6b8fSAnthony Liguori footer->checksum = be32_to_cpu(vpc_checksum(buf, HEADER_SIZE)); 540019d6b8fSAnthony Liguori 541019d6b8fSAnthony Liguori // Write the footer (twice: at the beginning and at the end) 542019d6b8fSAnthony Liguori block_size = 0x200000; 543019d6b8fSAnthony Liguori num_bat_entries = (total_sectors + block_size / 512) / (block_size / 512); 544019d6b8fSAnthony Liguori 545019d6b8fSAnthony Liguori if (write(fd, buf, HEADER_SIZE) != HEADER_SIZE) 546019d6b8fSAnthony Liguori return -EIO; 547019d6b8fSAnthony Liguori 548019d6b8fSAnthony Liguori if (lseek(fd, 1536 + ((num_bat_entries * 4 + 511) & ~511), SEEK_SET) < 0) 549019d6b8fSAnthony Liguori return -EIO; 550019d6b8fSAnthony Liguori if (write(fd, buf, HEADER_SIZE) != HEADER_SIZE) 551019d6b8fSAnthony Liguori return -EIO; 552019d6b8fSAnthony Liguori 553019d6b8fSAnthony Liguori // Write the initial BAT 554019d6b8fSAnthony Liguori if (lseek(fd, 3 * 512, SEEK_SET) < 0) 555019d6b8fSAnthony Liguori return -EIO; 556019d6b8fSAnthony Liguori 557019d6b8fSAnthony Liguori memset(buf, 0xFF, 512); 558019d6b8fSAnthony Liguori for (i = 0; i < (num_bat_entries * 4 + 511) / 512; i++) 559019d6b8fSAnthony Liguori if (write(fd, buf, 512) != 512) 560019d6b8fSAnthony Liguori return -EIO; 561019d6b8fSAnthony Liguori 562019d6b8fSAnthony Liguori 563019d6b8fSAnthony Liguori // Prepare the Dynamic Disk Header 564019d6b8fSAnthony Liguori memset(buf, 0, 1024); 565019d6b8fSAnthony Liguori 566*5ec4d682SNathan Froyd memcpy(dyndisk_header->magic, "cxsparse", 8); 567019d6b8fSAnthony Liguori 568019d6b8fSAnthony Liguori dyndisk_header->data_offset = be64_to_cpu(0xFFFFFFFF); 569019d6b8fSAnthony Liguori dyndisk_header->table_offset = be64_to_cpu(3 * 512); 570019d6b8fSAnthony Liguori dyndisk_header->version = be32_to_cpu(0x00010000); 571019d6b8fSAnthony Liguori dyndisk_header->block_size = be32_to_cpu(block_size); 572019d6b8fSAnthony Liguori dyndisk_header->max_table_entries = be32_to_cpu(num_bat_entries); 573019d6b8fSAnthony Liguori 574019d6b8fSAnthony Liguori dyndisk_header->checksum = be32_to_cpu(vpc_checksum(buf, 1024)); 575019d6b8fSAnthony Liguori 576019d6b8fSAnthony Liguori // Write the header 577019d6b8fSAnthony Liguori if (lseek(fd, 512, SEEK_SET) < 0) 578019d6b8fSAnthony Liguori return -EIO; 579019d6b8fSAnthony Liguori if (write(fd, buf, 1024) != 1024) 580019d6b8fSAnthony Liguori return -EIO; 581019d6b8fSAnthony Liguori 582019d6b8fSAnthony Liguori close(fd); 583019d6b8fSAnthony Liguori return 0; 584019d6b8fSAnthony Liguori } 585019d6b8fSAnthony Liguori 586019d6b8fSAnthony Liguori static void vpc_close(BlockDriverState *bs) 587019d6b8fSAnthony Liguori { 588019d6b8fSAnthony Liguori BDRVVPCState *s = bs->opaque; 589019d6b8fSAnthony Liguori qemu_free(s->pagetable); 590019d6b8fSAnthony Liguori #ifdef CACHE 591019d6b8fSAnthony Liguori qemu_free(s->pageentry_u8); 592019d6b8fSAnthony Liguori #endif 593019d6b8fSAnthony Liguori bdrv_delete(s->hd); 594019d6b8fSAnthony Liguori } 595019d6b8fSAnthony Liguori 5960e7e1989SKevin Wolf static QEMUOptionParameter vpc_create_options[] = { 597db08adf5SKevin Wolf { 598db08adf5SKevin Wolf .name = BLOCK_OPT_SIZE, 599db08adf5SKevin Wolf .type = OPT_SIZE, 600db08adf5SKevin Wolf .help = "Virtual disk size" 601db08adf5SKevin Wolf }, 6020e7e1989SKevin Wolf { NULL } 6030e7e1989SKevin Wolf }; 6040e7e1989SKevin Wolf 605019d6b8fSAnthony Liguori static BlockDriver bdrv_vpc = { 606019d6b8fSAnthony Liguori .format_name = "vpc", 607019d6b8fSAnthony Liguori .instance_size = sizeof(BDRVVPCState), 608019d6b8fSAnthony Liguori .bdrv_probe = vpc_probe, 609019d6b8fSAnthony Liguori .bdrv_open = vpc_open, 610019d6b8fSAnthony Liguori .bdrv_read = vpc_read, 611019d6b8fSAnthony Liguori .bdrv_write = vpc_write, 612019d6b8fSAnthony Liguori .bdrv_close = vpc_close, 613019d6b8fSAnthony Liguori .bdrv_create = vpc_create, 6140e7e1989SKevin Wolf 6150e7e1989SKevin Wolf .create_options = vpc_create_options, 616019d6b8fSAnthony Liguori }; 617019d6b8fSAnthony Liguori 618019d6b8fSAnthony Liguori static void bdrv_vpc_init(void) 619019d6b8fSAnthony Liguori { 620019d6b8fSAnthony Liguori bdrv_register(&bdrv_vpc); 621019d6b8fSAnthony Liguori } 622019d6b8fSAnthony Liguori 623019d6b8fSAnthony Liguori block_init(bdrv_vpc_init); 624