1 /* 2 * Block driver for Parallels disk image format 3 * 4 * Copyright (c) 2007 Alex Beregszaszi 5 * 6 * This code is based on comparing different disk images created by Parallels. 7 * 8 * Permission is hereby granted, free of charge, to any person obtaining a copy 9 * of this software and associated documentation files (the "Software"), to deal 10 * in the Software without restriction, including without limitation the rights 11 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 12 * copies of the Software, and to permit persons to whom the Software is 13 * furnished to do so, subject to the following conditions: 14 * 15 * The above copyright notice and this permission notice shall be included in 16 * all copies or substantial portions of the Software. 17 * 18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 21 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 22 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 23 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 24 * THE SOFTWARE. 25 */ 26 #include "qemu-common.h" 27 #include "block/block_int.h" 28 #include "qemu/module.h" 29 30 /**************************************************************/ 31 32 #define HEADER_MAGIC "WithoutFreeSpace" 33 #define HEADER_VERSION 2 34 #define HEADER_SIZE 64 35 36 // always little-endian 37 struct parallels_header { 38 char magic[16]; // "WithoutFreeSpace" 39 uint32_t version; 40 uint32_t heads; 41 uint32_t cylinders; 42 uint32_t tracks; 43 uint32_t catalog_entries; 44 uint32_t nb_sectors; 45 char padding[24]; 46 } QEMU_PACKED; 47 48 typedef struct BDRVParallelsState { 49 CoMutex lock; 50 51 uint32_t *catalog_bitmap; 52 int catalog_size; 53 54 int tracks; 55 } BDRVParallelsState; 56 57 static int parallels_probe(const uint8_t *buf, int buf_size, const char *filename) 58 { 59 const struct parallels_header *ph = (const void *)buf; 60 61 if (buf_size < HEADER_SIZE) 62 return 0; 63 64 if (!memcmp(ph->magic, HEADER_MAGIC, 16) && 65 (le32_to_cpu(ph->version) == HEADER_VERSION)) 66 return 100; 67 68 return 0; 69 } 70 71 static int parallels_open(BlockDriverState *bs, QDict *options, int flags, 72 Error **errp) 73 { 74 BDRVParallelsState *s = bs->opaque; 75 int i; 76 struct parallels_header ph; 77 int ret; 78 79 bs->read_only = 1; // no write support yet 80 81 ret = bdrv_pread(bs->file, 0, &ph, sizeof(ph)); 82 if (ret < 0) { 83 goto fail; 84 } 85 86 if (memcmp(ph.magic, HEADER_MAGIC, 16) || 87 (le32_to_cpu(ph.version) != HEADER_VERSION)) { 88 ret = -EMEDIUMTYPE; 89 goto fail; 90 } 91 92 bs->total_sectors = le32_to_cpu(ph.nb_sectors); 93 94 s->tracks = le32_to_cpu(ph.tracks); 95 96 s->catalog_size = le32_to_cpu(ph.catalog_entries); 97 s->catalog_bitmap = g_malloc(s->catalog_size * 4); 98 99 ret = bdrv_pread(bs->file, 64, s->catalog_bitmap, s->catalog_size * 4); 100 if (ret < 0) { 101 goto fail; 102 } 103 104 for (i = 0; i < s->catalog_size; i++) 105 le32_to_cpus(&s->catalog_bitmap[i]); 106 107 qemu_co_mutex_init(&s->lock); 108 return 0; 109 110 fail: 111 g_free(s->catalog_bitmap); 112 return ret; 113 } 114 115 static int64_t seek_to_sector(BlockDriverState *bs, int64_t sector_num) 116 { 117 BDRVParallelsState *s = bs->opaque; 118 uint32_t index, offset; 119 120 index = sector_num / s->tracks; 121 offset = sector_num % s->tracks; 122 123 /* not allocated */ 124 if ((index > s->catalog_size) || (s->catalog_bitmap[index] == 0)) 125 return -1; 126 return (uint64_t)(s->catalog_bitmap[index] + offset) * 512; 127 } 128 129 static int parallels_read(BlockDriverState *bs, int64_t sector_num, 130 uint8_t *buf, int nb_sectors) 131 { 132 while (nb_sectors > 0) { 133 int64_t position = seek_to_sector(bs, sector_num); 134 if (position >= 0) { 135 if (bdrv_pread(bs->file, position, buf, 512) != 512) 136 return -1; 137 } else { 138 memset(buf, 0, 512); 139 } 140 nb_sectors--; 141 sector_num++; 142 buf += 512; 143 } 144 return 0; 145 } 146 147 static coroutine_fn int parallels_co_read(BlockDriverState *bs, int64_t sector_num, 148 uint8_t *buf, int nb_sectors) 149 { 150 int ret; 151 BDRVParallelsState *s = bs->opaque; 152 qemu_co_mutex_lock(&s->lock); 153 ret = parallels_read(bs, sector_num, buf, nb_sectors); 154 qemu_co_mutex_unlock(&s->lock); 155 return ret; 156 } 157 158 static void parallels_close(BlockDriverState *bs) 159 { 160 BDRVParallelsState *s = bs->opaque; 161 g_free(s->catalog_bitmap); 162 } 163 164 static BlockDriver bdrv_parallels = { 165 .format_name = "parallels", 166 .instance_size = sizeof(BDRVParallelsState), 167 .bdrv_probe = parallels_probe, 168 .bdrv_open = parallels_open, 169 .bdrv_read = parallels_co_read, 170 .bdrv_close = parallels_close, 171 }; 172 173 static void bdrv_parallels_init(void) 174 { 175 bdrv_register(&bdrv_parallels); 176 } 177 178 block_init(bdrv_parallels_init); 179