bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Block driver for the QCOW version 2 format |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 3 | * |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 4 | * Copyright (c) 2004-2006 Fabrice Bellard |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 5 | * |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 6 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| 7 | * of this software and associated documentation files (the "Software"), to deal |
| 8 | * in the Software without restriction, including without limitation the rights |
| 9 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| 10 | * copies of the Software, and to permit persons to whom the Software is |
| 11 | * furnished to do so, subject to the following conditions: |
| 12 | * |
| 13 | * The above copyright notice and this permission notice shall be included in |
| 14 | * all copies or substantial portions of the Software. |
| 15 | * |
| 16 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 17 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 18 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| 19 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 20 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| 21 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| 22 | * THE SOFTWARE. |
| 23 | */ |
pbrook | faf0796 | 2007-11-11 02:51:17 +0000 | [diff] [blame] | 24 | #include "qemu-common.h" |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 25 | #include "block_int.h" |
| 26 | #include <zlib.h> |
| 27 | #include "aes.h" |
| 28 | #include <assert.h> |
| 29 | |
| 30 | /* |
| 31 | Differences with QCOW: |
| 32 | |
| 33 | - Support for multiple incremental snapshots. |
| 34 | - Memory management by reference counts. |
| 35 | - Clusters which have a reference count of one have the bit |
| 36 | QCOW_OFLAG_COPIED to optimize write performance. |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 37 | - Size of compressed clusters is stored in sectors to reduce bit usage |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 38 | in the cluster offsets. |
| 39 | - Support for storing additional data (such as the VM state) in the |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 40 | snapshots. |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 41 | - If a backing store is used, the cluster size is not constrained |
| 42 | (could be backported to QCOW). |
| 43 | - L2 tables have always a size of one cluster. |
| 44 | */ |
| 45 | |
| 46 | //#define DEBUG_ALLOC |
| 47 | //#define DEBUG_ALLOC2 |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 48 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 49 | #define QCOW_MAGIC (('Q' << 24) | ('F' << 16) | ('I' << 8) | 0xfb) |
| 50 | #define QCOW_VERSION 2 |
| 51 | |
| 52 | #define QCOW_CRYPT_NONE 0 |
| 53 | #define QCOW_CRYPT_AES 1 |
| 54 | |
| 55 | /* indicate that the refcount of the referenced cluster is exactly one. */ |
| 56 | #define QCOW_OFLAG_COPIED (1LL << 63) |
| 57 | /* indicate that the cluster is compressed (they never have the copied flag) */ |
| 58 | #define QCOW_OFLAG_COMPRESSED (1LL << 62) |
| 59 | |
| 60 | #define REFCOUNT_SHIFT 1 /* refcount size is 2 bytes */ |
| 61 | |
| 62 | #ifndef offsetof |
| 63 | #define offsetof(type, field) ((size_t) &((type *)0)->field) |
| 64 | #endif |
| 65 | |
| 66 | typedef struct QCowHeader { |
| 67 | uint32_t magic; |
| 68 | uint32_t version; |
| 69 | uint64_t backing_file_offset; |
| 70 | uint32_t backing_file_size; |
| 71 | uint32_t cluster_bits; |
| 72 | uint64_t size; /* in bytes */ |
| 73 | uint32_t crypt_method; |
| 74 | uint32_t l1_size; /* XXX: save number of clusters instead ? */ |
| 75 | uint64_t l1_table_offset; |
| 76 | uint64_t refcount_table_offset; |
| 77 | uint32_t refcount_table_clusters; |
| 78 | uint32_t nb_snapshots; |
| 79 | uint64_t snapshots_offset; |
| 80 | } QCowHeader; |
| 81 | |
| 82 | typedef struct __attribute__((packed)) QCowSnapshotHeader { |
| 83 | /* header is 8 byte aligned */ |
| 84 | uint64_t l1_table_offset; |
| 85 | |
| 86 | uint32_t l1_size; |
| 87 | uint16_t id_str_size; |
| 88 | uint16_t name_size; |
| 89 | |
| 90 | uint32_t date_sec; |
| 91 | uint32_t date_nsec; |
| 92 | |
| 93 | uint64_t vm_clock_nsec; |
| 94 | |
| 95 | uint32_t vm_state_size; |
| 96 | uint32_t extra_data_size; /* for extension */ |
| 97 | /* extra data follows */ |
| 98 | /* id_str follows */ |
| 99 | /* name follows */ |
| 100 | } QCowSnapshotHeader; |
| 101 | |
| 102 | #define L2_CACHE_SIZE 16 |
| 103 | |
| 104 | typedef struct QCowSnapshot { |
| 105 | uint64_t l1_table_offset; |
| 106 | uint32_t l1_size; |
| 107 | char *id_str; |
| 108 | char *name; |
| 109 | uint32_t vm_state_size; |
| 110 | uint32_t date_sec; |
| 111 | uint32_t date_nsec; |
| 112 | uint64_t vm_clock_nsec; |
| 113 | } QCowSnapshot; |
| 114 | |
| 115 | typedef struct BDRVQcowState { |
| 116 | BlockDriverState *hd; |
| 117 | int cluster_bits; |
| 118 | int cluster_size; |
| 119 | int cluster_sectors; |
| 120 | int l2_bits; |
| 121 | int l2_size; |
| 122 | int l1_size; |
| 123 | int l1_vm_state_index; |
| 124 | int csize_shift; |
| 125 | int csize_mask; |
| 126 | uint64_t cluster_offset_mask; |
| 127 | uint64_t l1_table_offset; |
| 128 | uint64_t *l1_table; |
| 129 | uint64_t *l2_cache; |
| 130 | uint64_t l2_cache_offsets[L2_CACHE_SIZE]; |
| 131 | uint32_t l2_cache_counts[L2_CACHE_SIZE]; |
| 132 | uint8_t *cluster_cache; |
| 133 | uint8_t *cluster_data; |
| 134 | uint64_t cluster_cache_offset; |
| 135 | |
| 136 | uint64_t *refcount_table; |
| 137 | uint64_t refcount_table_offset; |
| 138 | uint32_t refcount_table_size; |
| 139 | uint64_t refcount_block_cache_offset; |
| 140 | uint16_t *refcount_block_cache; |
| 141 | int64_t free_cluster_index; |
| 142 | int64_t free_byte_offset; |
| 143 | |
| 144 | uint32_t crypt_method; /* current crypt method, 0 if no key yet */ |
| 145 | uint32_t crypt_method_header; |
| 146 | AES_KEY aes_encrypt_key; |
| 147 | AES_KEY aes_decrypt_key; |
| 148 | uint64_t snapshots_offset; |
| 149 | int snapshots_size; |
| 150 | int nb_snapshots; |
| 151 | QCowSnapshot *snapshots; |
| 152 | } BDRVQcowState; |
| 153 | |
| 154 | static int decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset); |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 155 | static int qcow_read(BlockDriverState *bs, int64_t sector_num, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 156 | uint8_t *buf, int nb_sectors); |
| 157 | static int qcow_read_snapshots(BlockDriverState *bs); |
| 158 | static void qcow_free_snapshots(BlockDriverState *bs); |
| 159 | static int refcount_init(BlockDriverState *bs); |
| 160 | static void refcount_close(BlockDriverState *bs); |
| 161 | static int get_refcount(BlockDriverState *bs, int64_t cluster_index); |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 162 | static int update_cluster_refcount(BlockDriverState *bs, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 163 | int64_t cluster_index, |
| 164 | int addend); |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 165 | static void update_refcount(BlockDriverState *bs, |
| 166 | int64_t offset, int64_t length, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 167 | int addend); |
| 168 | static int64_t alloc_clusters(BlockDriverState *bs, int64_t size); |
| 169 | static int64_t alloc_bytes(BlockDriverState *bs, int size); |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 170 | static void free_clusters(BlockDriverState *bs, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 171 | int64_t offset, int64_t size); |
| 172 | #ifdef DEBUG_ALLOC |
| 173 | static void check_refcounts(BlockDriverState *bs); |
| 174 | #endif |
| 175 | |
| 176 | static int qcow_probe(const uint8_t *buf, int buf_size, const char *filename) |
| 177 | { |
| 178 | const QCowHeader *cow_header = (const void *)buf; |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 179 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 180 | if (buf_size >= sizeof(QCowHeader) && |
| 181 | be32_to_cpu(cow_header->magic) == QCOW_MAGIC && |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 182 | be32_to_cpu(cow_header->version) == QCOW_VERSION) |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 183 | return 100; |
| 184 | else |
| 185 | return 0; |
| 186 | } |
| 187 | |
| 188 | static int qcow_open(BlockDriverState *bs, const char *filename, int flags) |
| 189 | { |
| 190 | BDRVQcowState *s = bs->opaque; |
| 191 | int len, i, shift, ret; |
| 192 | QCowHeader header; |
| 193 | |
aurel32 | b5eff35 | 2008-03-11 23:30:22 +0000 | [diff] [blame] | 194 | ret = bdrv_file_open(&s->hd, filename, flags); |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 195 | if (ret < 0) |
| 196 | return ret; |
| 197 | if (bdrv_pread(s->hd, 0, &header, sizeof(header)) != sizeof(header)) |
| 198 | goto fail; |
| 199 | be32_to_cpus(&header.magic); |
| 200 | be32_to_cpus(&header.version); |
| 201 | be64_to_cpus(&header.backing_file_offset); |
| 202 | be32_to_cpus(&header.backing_file_size); |
| 203 | be64_to_cpus(&header.size); |
| 204 | be32_to_cpus(&header.cluster_bits); |
| 205 | be32_to_cpus(&header.crypt_method); |
| 206 | be64_to_cpus(&header.l1_table_offset); |
| 207 | be32_to_cpus(&header.l1_size); |
| 208 | be64_to_cpus(&header.refcount_table_offset); |
| 209 | be32_to_cpus(&header.refcount_table_clusters); |
| 210 | be64_to_cpus(&header.snapshots_offset); |
| 211 | be32_to_cpus(&header.nb_snapshots); |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 212 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 213 | if (header.magic != QCOW_MAGIC || header.version != QCOW_VERSION) |
| 214 | goto fail; |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 215 | if (header.size <= 1 || |
| 216 | header.cluster_bits < 9 || |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 217 | header.cluster_bits > 16) |
| 218 | goto fail; |
| 219 | if (header.crypt_method > QCOW_CRYPT_AES) |
| 220 | goto fail; |
| 221 | s->crypt_method_header = header.crypt_method; |
| 222 | if (s->crypt_method_header) |
| 223 | bs->encrypted = 1; |
| 224 | s->cluster_bits = header.cluster_bits; |
| 225 | s->cluster_size = 1 << s->cluster_bits; |
| 226 | s->cluster_sectors = 1 << (s->cluster_bits - 9); |
| 227 | s->l2_bits = s->cluster_bits - 3; /* L2 is always one cluster */ |
| 228 | s->l2_size = 1 << s->l2_bits; |
| 229 | bs->total_sectors = header.size / 512; |
| 230 | s->csize_shift = (62 - (s->cluster_bits - 8)); |
| 231 | s->csize_mask = (1 << (s->cluster_bits - 8)) - 1; |
| 232 | s->cluster_offset_mask = (1LL << s->csize_shift) - 1; |
| 233 | s->refcount_table_offset = header.refcount_table_offset; |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 234 | s->refcount_table_size = |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 235 | header.refcount_table_clusters << (s->cluster_bits - 3); |
| 236 | |
| 237 | s->snapshots_offset = header.snapshots_offset; |
| 238 | s->nb_snapshots = header.nb_snapshots; |
| 239 | |
| 240 | /* read the level 1 table */ |
| 241 | s->l1_size = header.l1_size; |
| 242 | shift = s->cluster_bits + s->l2_bits; |
| 243 | s->l1_vm_state_index = (header.size + (1LL << shift) - 1) >> shift; |
| 244 | /* the L1 table must contain at least enough entries to put |
| 245 | header.size bytes */ |
| 246 | if (s->l1_size < s->l1_vm_state_index) |
| 247 | goto fail; |
| 248 | s->l1_table_offset = header.l1_table_offset; |
| 249 | s->l1_table = qemu_malloc(s->l1_size * sizeof(uint64_t)); |
| 250 | if (!s->l1_table) |
| 251 | goto fail; |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 252 | if (bdrv_pread(s->hd, s->l1_table_offset, s->l1_table, s->l1_size * sizeof(uint64_t)) != |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 253 | s->l1_size * sizeof(uint64_t)) |
| 254 | goto fail; |
| 255 | for(i = 0;i < s->l1_size; i++) { |
| 256 | be64_to_cpus(&s->l1_table[i]); |
| 257 | } |
| 258 | /* alloc L2 cache */ |
| 259 | s->l2_cache = qemu_malloc(s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t)); |
| 260 | if (!s->l2_cache) |
| 261 | goto fail; |
| 262 | s->cluster_cache = qemu_malloc(s->cluster_size); |
| 263 | if (!s->cluster_cache) |
| 264 | goto fail; |
| 265 | /* one more sector for decompressed data alignment */ |
| 266 | s->cluster_data = qemu_malloc(s->cluster_size + 512); |
| 267 | if (!s->cluster_data) |
| 268 | goto fail; |
| 269 | s->cluster_cache_offset = -1; |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 270 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 271 | if (refcount_init(bs) < 0) |
| 272 | goto fail; |
| 273 | |
| 274 | /* read the backing file name */ |
| 275 | if (header.backing_file_offset != 0) { |
| 276 | len = header.backing_file_size; |
| 277 | if (len > 1023) |
| 278 | len = 1023; |
| 279 | if (bdrv_pread(s->hd, header.backing_file_offset, bs->backing_file, len) != len) |
| 280 | goto fail; |
| 281 | bs->backing_file[len] = '\0'; |
| 282 | } |
| 283 | if (qcow_read_snapshots(bs) < 0) |
| 284 | goto fail; |
| 285 | |
| 286 | #ifdef DEBUG_ALLOC |
| 287 | check_refcounts(bs); |
| 288 | #endif |
| 289 | return 0; |
| 290 | |
| 291 | fail: |
| 292 | qcow_free_snapshots(bs); |
| 293 | refcount_close(bs); |
| 294 | qemu_free(s->l1_table); |
| 295 | qemu_free(s->l2_cache); |
| 296 | qemu_free(s->cluster_cache); |
| 297 | qemu_free(s->cluster_data); |
| 298 | bdrv_delete(s->hd); |
| 299 | return -1; |
| 300 | } |
| 301 | |
| 302 | static int qcow_set_key(BlockDriverState *bs, const char *key) |
| 303 | { |
| 304 | BDRVQcowState *s = bs->opaque; |
| 305 | uint8_t keybuf[16]; |
| 306 | int len, i; |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 307 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 308 | memset(keybuf, 0, 16); |
| 309 | len = strlen(key); |
| 310 | if (len > 16) |
| 311 | len = 16; |
| 312 | /* XXX: we could compress the chars to 7 bits to increase |
| 313 | entropy */ |
| 314 | for(i = 0;i < len;i++) { |
| 315 | keybuf[i] = key[i]; |
| 316 | } |
| 317 | s->crypt_method = s->crypt_method_header; |
| 318 | |
| 319 | if (AES_set_encrypt_key(keybuf, 128, &s->aes_encrypt_key) != 0) |
| 320 | return -1; |
| 321 | if (AES_set_decrypt_key(keybuf, 128, &s->aes_decrypt_key) != 0) |
| 322 | return -1; |
| 323 | #if 0 |
| 324 | /* test */ |
| 325 | { |
| 326 | uint8_t in[16]; |
| 327 | uint8_t out[16]; |
| 328 | uint8_t tmp[16]; |
| 329 | for(i=0;i<16;i++) |
| 330 | in[i] = i; |
| 331 | AES_encrypt(in, tmp, &s->aes_encrypt_key); |
| 332 | AES_decrypt(tmp, out, &s->aes_decrypt_key); |
| 333 | for(i = 0; i < 16; i++) |
| 334 | printf(" %02x", tmp[i]); |
| 335 | printf("\n"); |
| 336 | for(i = 0; i < 16; i++) |
| 337 | printf(" %02x", out[i]); |
| 338 | printf("\n"); |
| 339 | } |
| 340 | #endif |
| 341 | return 0; |
| 342 | } |
| 343 | |
| 344 | /* The crypt function is compatible with the linux cryptoloop |
| 345 | algorithm for < 4 GB images. NOTE: out_buf == in_buf is |
| 346 | supported */ |
| 347 | static void encrypt_sectors(BDRVQcowState *s, int64_t sector_num, |
| 348 | uint8_t *out_buf, const uint8_t *in_buf, |
| 349 | int nb_sectors, int enc, |
| 350 | const AES_KEY *key) |
| 351 | { |
| 352 | union { |
| 353 | uint64_t ll[2]; |
| 354 | uint8_t b[16]; |
| 355 | } ivec; |
| 356 | int i; |
| 357 | |
| 358 | for(i = 0; i < nb_sectors; i++) { |
| 359 | ivec.ll[0] = cpu_to_le64(sector_num); |
| 360 | ivec.ll[1] = 0; |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 361 | AES_cbc_encrypt(in_buf, out_buf, 512, key, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 362 | ivec.b, enc); |
| 363 | sector_num++; |
| 364 | in_buf += 512; |
| 365 | out_buf += 512; |
| 366 | } |
| 367 | } |
| 368 | |
| 369 | static int copy_sectors(BlockDriverState *bs, uint64_t start_sect, |
| 370 | uint64_t cluster_offset, int n_start, int n_end) |
| 371 | { |
| 372 | BDRVQcowState *s = bs->opaque; |
| 373 | int n, ret; |
| 374 | |
| 375 | n = n_end - n_start; |
| 376 | if (n <= 0) |
| 377 | return 0; |
| 378 | ret = qcow_read(bs, start_sect + n_start, s->cluster_data, n); |
| 379 | if (ret < 0) |
| 380 | return ret; |
| 381 | if (s->crypt_method) { |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 382 | encrypt_sectors(s, start_sect + n_start, |
| 383 | s->cluster_data, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 384 | s->cluster_data, n, 1, |
| 385 | &s->aes_encrypt_key); |
| 386 | } |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 387 | ret = bdrv_write(s->hd, (cluster_offset >> 9) + n_start, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 388 | s->cluster_data, n); |
| 389 | if (ret < 0) |
| 390 | return ret; |
| 391 | return 0; |
| 392 | } |
| 393 | |
| 394 | static void l2_cache_reset(BlockDriverState *bs) |
| 395 | { |
| 396 | BDRVQcowState *s = bs->opaque; |
| 397 | |
| 398 | memset(s->l2_cache, 0, s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t)); |
| 399 | memset(s->l2_cache_offsets, 0, L2_CACHE_SIZE * sizeof(uint64_t)); |
| 400 | memset(s->l2_cache_counts, 0, L2_CACHE_SIZE * sizeof(uint32_t)); |
| 401 | } |
| 402 | |
| 403 | static inline int l2_cache_new_entry(BlockDriverState *bs) |
| 404 | { |
| 405 | BDRVQcowState *s = bs->opaque; |
| 406 | uint32_t min_count; |
| 407 | int min_index, i; |
| 408 | |
| 409 | /* find a new entry in the least used one */ |
| 410 | min_index = 0; |
| 411 | min_count = 0xffffffff; |
| 412 | for(i = 0; i < L2_CACHE_SIZE; i++) { |
| 413 | if (s->l2_cache_counts[i] < min_count) { |
| 414 | min_count = s->l2_cache_counts[i]; |
| 415 | min_index = i; |
| 416 | } |
| 417 | } |
| 418 | return min_index; |
| 419 | } |
| 420 | |
| 421 | static int64_t align_offset(int64_t offset, int n) |
| 422 | { |
| 423 | offset = (offset + n - 1) & ~(n - 1); |
| 424 | return offset; |
| 425 | } |
| 426 | |
| 427 | static int grow_l1_table(BlockDriverState *bs, int min_size) |
| 428 | { |
| 429 | BDRVQcowState *s = bs->opaque; |
| 430 | int new_l1_size, new_l1_size2, ret, i; |
| 431 | uint64_t *new_l1_table; |
| 432 | uint64_t new_l1_table_offset; |
| 433 | uint64_t data64; |
| 434 | uint32_t data32; |
| 435 | |
| 436 | new_l1_size = s->l1_size; |
| 437 | if (min_size <= new_l1_size) |
| 438 | return 0; |
| 439 | while (min_size > new_l1_size) { |
| 440 | new_l1_size = (new_l1_size * 3 + 1) / 2; |
| 441 | } |
| 442 | #ifdef DEBUG_ALLOC2 |
| 443 | printf("grow l1_table from %d to %d\n", s->l1_size, new_l1_size); |
| 444 | #endif |
| 445 | |
| 446 | new_l1_size2 = sizeof(uint64_t) * new_l1_size; |
| 447 | new_l1_table = qemu_mallocz(new_l1_size2); |
| 448 | if (!new_l1_table) |
| 449 | return -ENOMEM; |
| 450 | memcpy(new_l1_table, s->l1_table, s->l1_size * sizeof(uint64_t)); |
| 451 | |
| 452 | /* write new table (align to cluster) */ |
| 453 | new_l1_table_offset = alloc_clusters(bs, new_l1_size2); |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 454 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 455 | for(i = 0; i < s->l1_size; i++) |
| 456 | new_l1_table[i] = cpu_to_be64(new_l1_table[i]); |
| 457 | ret = bdrv_pwrite(s->hd, new_l1_table_offset, new_l1_table, new_l1_size2); |
| 458 | if (ret != new_l1_size2) |
| 459 | goto fail; |
| 460 | for(i = 0; i < s->l1_size; i++) |
| 461 | new_l1_table[i] = be64_to_cpu(new_l1_table[i]); |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 462 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 463 | /* set new table */ |
| 464 | data64 = cpu_to_be64(new_l1_table_offset); |
| 465 | if (bdrv_pwrite(s->hd, offsetof(QCowHeader, l1_table_offset), |
| 466 | &data64, sizeof(data64)) != sizeof(data64)) |
| 467 | goto fail; |
| 468 | data32 = cpu_to_be32(new_l1_size); |
| 469 | if (bdrv_pwrite(s->hd, offsetof(QCowHeader, l1_size), |
| 470 | &data32, sizeof(data32)) != sizeof(data32)) |
| 471 | goto fail; |
| 472 | qemu_free(s->l1_table); |
| 473 | free_clusters(bs, s->l1_table_offset, s->l1_size * sizeof(uint64_t)); |
| 474 | s->l1_table_offset = new_l1_table_offset; |
| 475 | s->l1_table = new_l1_table; |
| 476 | s->l1_size = new_l1_size; |
| 477 | return 0; |
| 478 | fail: |
| 479 | qemu_free(s->l1_table); |
| 480 | return -EIO; |
| 481 | } |
| 482 | |
| 483 | /* 'allocate' is: |
| 484 | * |
| 485 | * 0 not to allocate. |
| 486 | * |
| 487 | * 1 to allocate a normal cluster (for sector indexes 'n_start' to |
| 488 | * 'n_end') |
| 489 | * |
| 490 | * 2 to allocate a compressed cluster of size |
| 491 | * 'compressed_size'. 'compressed_size' must be > 0 and < |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 492 | * cluster_size |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 493 | * |
| 494 | * return 0 if not allocated. |
| 495 | */ |
| 496 | static uint64_t get_cluster_offset(BlockDriverState *bs, |
| 497 | uint64_t offset, int allocate, |
| 498 | int compressed_size, |
| 499 | int n_start, int n_end) |
| 500 | { |
| 501 | BDRVQcowState *s = bs->opaque; |
| 502 | int min_index, i, j, l1_index, l2_index, ret; |
| 503 | uint64_t l2_offset, *l2_table, cluster_offset, tmp, old_l2_offset; |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 504 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 505 | l1_index = offset >> (s->l2_bits + s->cluster_bits); |
| 506 | if (l1_index >= s->l1_size) { |
| 507 | /* outside l1 table is allowed: we grow the table if needed */ |
| 508 | if (!allocate) |
| 509 | return 0; |
| 510 | if (grow_l1_table(bs, l1_index + 1) < 0) |
| 511 | return 0; |
| 512 | } |
| 513 | l2_offset = s->l1_table[l1_index]; |
| 514 | if (!l2_offset) { |
| 515 | if (!allocate) |
| 516 | return 0; |
| 517 | l2_allocate: |
| 518 | old_l2_offset = l2_offset; |
| 519 | /* allocate a new l2 entry */ |
| 520 | l2_offset = alloc_clusters(bs, s->l2_size * sizeof(uint64_t)); |
| 521 | /* update the L1 entry */ |
| 522 | s->l1_table[l1_index] = l2_offset | QCOW_OFLAG_COPIED; |
| 523 | tmp = cpu_to_be64(l2_offset | QCOW_OFLAG_COPIED); |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 524 | if (bdrv_pwrite(s->hd, s->l1_table_offset + l1_index * sizeof(tmp), |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 525 | &tmp, sizeof(tmp)) != sizeof(tmp)) |
| 526 | return 0; |
| 527 | min_index = l2_cache_new_entry(bs); |
| 528 | l2_table = s->l2_cache + (min_index << s->l2_bits); |
| 529 | |
| 530 | if (old_l2_offset == 0) { |
| 531 | memset(l2_table, 0, s->l2_size * sizeof(uint64_t)); |
| 532 | } else { |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 533 | if (bdrv_pread(s->hd, old_l2_offset, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 534 | l2_table, s->l2_size * sizeof(uint64_t)) != |
| 535 | s->l2_size * sizeof(uint64_t)) |
| 536 | return 0; |
| 537 | } |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 538 | if (bdrv_pwrite(s->hd, l2_offset, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 539 | l2_table, s->l2_size * sizeof(uint64_t)) != |
| 540 | s->l2_size * sizeof(uint64_t)) |
| 541 | return 0; |
| 542 | } else { |
| 543 | if (!(l2_offset & QCOW_OFLAG_COPIED)) { |
| 544 | if (allocate) { |
| 545 | free_clusters(bs, l2_offset, s->l2_size * sizeof(uint64_t)); |
| 546 | goto l2_allocate; |
| 547 | } |
| 548 | } else { |
| 549 | l2_offset &= ~QCOW_OFLAG_COPIED; |
| 550 | } |
| 551 | for(i = 0; i < L2_CACHE_SIZE; i++) { |
| 552 | if (l2_offset == s->l2_cache_offsets[i]) { |
| 553 | /* increment the hit count */ |
| 554 | if (++s->l2_cache_counts[i] == 0xffffffff) { |
| 555 | for(j = 0; j < L2_CACHE_SIZE; j++) { |
| 556 | s->l2_cache_counts[j] >>= 1; |
| 557 | } |
| 558 | } |
| 559 | l2_table = s->l2_cache + (i << s->l2_bits); |
| 560 | goto found; |
| 561 | } |
| 562 | } |
| 563 | /* not found: load a new entry in the least used one */ |
| 564 | min_index = l2_cache_new_entry(bs); |
| 565 | l2_table = s->l2_cache + (min_index << s->l2_bits); |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 566 | if (bdrv_pread(s->hd, l2_offset, l2_table, s->l2_size * sizeof(uint64_t)) != |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 567 | s->l2_size * sizeof(uint64_t)) |
| 568 | return 0; |
| 569 | } |
| 570 | s->l2_cache_offsets[min_index] = l2_offset; |
| 571 | s->l2_cache_counts[min_index] = 1; |
| 572 | found: |
| 573 | l2_index = (offset >> s->cluster_bits) & (s->l2_size - 1); |
| 574 | cluster_offset = be64_to_cpu(l2_table[l2_index]); |
| 575 | if (!cluster_offset) { |
| 576 | if (!allocate) |
| 577 | return cluster_offset; |
| 578 | } else if (!(cluster_offset & QCOW_OFLAG_COPIED)) { |
| 579 | if (!allocate) |
| 580 | return cluster_offset; |
| 581 | /* free the cluster */ |
| 582 | if (cluster_offset & QCOW_OFLAG_COMPRESSED) { |
| 583 | int nb_csectors; |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 584 | nb_csectors = ((cluster_offset >> s->csize_shift) & |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 585 | s->csize_mask) + 1; |
| 586 | free_clusters(bs, (cluster_offset & s->cluster_offset_mask) & ~511, |
| 587 | nb_csectors * 512); |
| 588 | } else { |
| 589 | free_clusters(bs, cluster_offset, s->cluster_size); |
| 590 | } |
| 591 | } else { |
| 592 | cluster_offset &= ~QCOW_OFLAG_COPIED; |
| 593 | return cluster_offset; |
| 594 | } |
| 595 | if (allocate == 1) { |
| 596 | /* allocate a new cluster */ |
| 597 | cluster_offset = alloc_clusters(bs, s->cluster_size); |
| 598 | |
| 599 | /* we must initialize the cluster content which won't be |
| 600 | written */ |
| 601 | if ((n_end - n_start) < s->cluster_sectors) { |
| 602 | uint64_t start_sect; |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 603 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 604 | start_sect = (offset & ~(s->cluster_size - 1)) >> 9; |
| 605 | ret = copy_sectors(bs, start_sect, |
| 606 | cluster_offset, 0, n_start); |
| 607 | if (ret < 0) |
| 608 | return 0; |
| 609 | ret = copy_sectors(bs, start_sect, |
| 610 | cluster_offset, n_end, s->cluster_sectors); |
| 611 | if (ret < 0) |
| 612 | return 0; |
| 613 | } |
| 614 | tmp = cpu_to_be64(cluster_offset | QCOW_OFLAG_COPIED); |
| 615 | } else { |
| 616 | int nb_csectors; |
| 617 | cluster_offset = alloc_bytes(bs, compressed_size); |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 618 | nb_csectors = ((cluster_offset + compressed_size - 1) >> 9) - |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 619 | (cluster_offset >> 9); |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 620 | cluster_offset |= QCOW_OFLAG_COMPRESSED | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 621 | ((uint64_t)nb_csectors << s->csize_shift); |
| 622 | /* compressed clusters never have the copied flag */ |
| 623 | tmp = cpu_to_be64(cluster_offset); |
| 624 | } |
| 625 | /* update L2 table */ |
| 626 | l2_table[l2_index] = tmp; |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 627 | if (bdrv_pwrite(s->hd, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 628 | l2_offset + l2_index * sizeof(tmp), &tmp, sizeof(tmp)) != sizeof(tmp)) |
| 629 | return 0; |
| 630 | return cluster_offset; |
| 631 | } |
| 632 | |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 633 | static int qcow_is_allocated(BlockDriverState *bs, int64_t sector_num, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 634 | int nb_sectors, int *pnum) |
| 635 | { |
| 636 | BDRVQcowState *s = bs->opaque; |
| 637 | int index_in_cluster, n; |
| 638 | uint64_t cluster_offset; |
| 639 | |
| 640 | cluster_offset = get_cluster_offset(bs, sector_num << 9, 0, 0, 0, 0); |
| 641 | index_in_cluster = sector_num & (s->cluster_sectors - 1); |
| 642 | n = s->cluster_sectors - index_in_cluster; |
| 643 | if (n > nb_sectors) |
| 644 | n = nb_sectors; |
| 645 | *pnum = n; |
| 646 | return (cluster_offset != 0); |
| 647 | } |
| 648 | |
| 649 | static int decompress_buffer(uint8_t *out_buf, int out_buf_size, |
| 650 | const uint8_t *buf, int buf_size) |
| 651 | { |
| 652 | z_stream strm1, *strm = &strm1; |
| 653 | int ret, out_len; |
| 654 | |
| 655 | memset(strm, 0, sizeof(*strm)); |
| 656 | |
| 657 | strm->next_in = (uint8_t *)buf; |
| 658 | strm->avail_in = buf_size; |
| 659 | strm->next_out = out_buf; |
| 660 | strm->avail_out = out_buf_size; |
| 661 | |
| 662 | ret = inflateInit2(strm, -12); |
| 663 | if (ret != Z_OK) |
| 664 | return -1; |
| 665 | ret = inflate(strm, Z_FINISH); |
| 666 | out_len = strm->next_out - out_buf; |
| 667 | if ((ret != Z_STREAM_END && ret != Z_BUF_ERROR) || |
| 668 | out_len != out_buf_size) { |
| 669 | inflateEnd(strm); |
| 670 | return -1; |
| 671 | } |
| 672 | inflateEnd(strm); |
| 673 | return 0; |
| 674 | } |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 675 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 676 | static int decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset) |
| 677 | { |
| 678 | int ret, csize, nb_csectors, sector_offset; |
| 679 | uint64_t coffset; |
| 680 | |
| 681 | coffset = cluster_offset & s->cluster_offset_mask; |
| 682 | if (s->cluster_cache_offset != coffset) { |
| 683 | nb_csectors = ((cluster_offset >> s->csize_shift) & s->csize_mask) + 1; |
| 684 | sector_offset = coffset & 511; |
| 685 | csize = nb_csectors * 512 - sector_offset; |
| 686 | ret = bdrv_read(s->hd, coffset >> 9, s->cluster_data, nb_csectors); |
| 687 | if (ret < 0) { |
| 688 | return -1; |
| 689 | } |
| 690 | if (decompress_buffer(s->cluster_cache, s->cluster_size, |
| 691 | s->cluster_data + sector_offset, csize) < 0) { |
| 692 | return -1; |
| 693 | } |
| 694 | s->cluster_cache_offset = coffset; |
| 695 | } |
| 696 | return 0; |
| 697 | } |
| 698 | |
bellard | a946592 | 2006-08-06 13:34:04 +0000 | [diff] [blame] | 699 | /* handle reading after the end of the backing file */ |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 700 | static int backing_read1(BlockDriverState *bs, |
bellard | a946592 | 2006-08-06 13:34:04 +0000 | [diff] [blame] | 701 | int64_t sector_num, uint8_t *buf, int nb_sectors) |
| 702 | { |
| 703 | int n1; |
| 704 | if ((sector_num + nb_sectors) <= bs->total_sectors) |
| 705 | return nb_sectors; |
| 706 | if (sector_num >= bs->total_sectors) |
| 707 | n1 = 0; |
| 708 | else |
| 709 | n1 = bs->total_sectors - sector_num; |
| 710 | memset(buf + n1 * 512, 0, 512 * (nb_sectors - n1)); |
| 711 | return n1; |
| 712 | } |
| 713 | |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 714 | static int qcow_read(BlockDriverState *bs, int64_t sector_num, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 715 | uint8_t *buf, int nb_sectors) |
| 716 | { |
| 717 | BDRVQcowState *s = bs->opaque; |
bellard | a946592 | 2006-08-06 13:34:04 +0000 | [diff] [blame] | 718 | int ret, index_in_cluster, n, n1; |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 719 | uint64_t cluster_offset; |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 720 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 721 | while (nb_sectors > 0) { |
| 722 | cluster_offset = get_cluster_offset(bs, sector_num << 9, 0, 0, 0, 0); |
| 723 | index_in_cluster = sector_num & (s->cluster_sectors - 1); |
| 724 | n = s->cluster_sectors - index_in_cluster; |
| 725 | if (n > nb_sectors) |
| 726 | n = nb_sectors; |
| 727 | if (!cluster_offset) { |
| 728 | if (bs->backing_hd) { |
| 729 | /* read from the base image */ |
bellard | a946592 | 2006-08-06 13:34:04 +0000 | [diff] [blame] | 730 | n1 = backing_read1(bs->backing_hd, sector_num, buf, n); |
| 731 | if (n1 > 0) { |
| 732 | ret = bdrv_read(bs->backing_hd, sector_num, buf, n1); |
| 733 | if (ret < 0) |
| 734 | return -1; |
| 735 | } |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 736 | } else { |
| 737 | memset(buf, 0, 512 * n); |
| 738 | } |
| 739 | } else if (cluster_offset & QCOW_OFLAG_COMPRESSED) { |
| 740 | if (decompress_cluster(s, cluster_offset) < 0) |
| 741 | return -1; |
| 742 | memcpy(buf, s->cluster_cache + index_in_cluster * 512, 512 * n); |
| 743 | } else { |
| 744 | ret = bdrv_pread(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512); |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 745 | if (ret != n * 512) |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 746 | return -1; |
| 747 | if (s->crypt_method) { |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 748 | encrypt_sectors(s, sector_num, buf, buf, n, 0, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 749 | &s->aes_decrypt_key); |
| 750 | } |
| 751 | } |
| 752 | nb_sectors -= n; |
| 753 | sector_num += n; |
| 754 | buf += n * 512; |
| 755 | } |
| 756 | return 0; |
| 757 | } |
| 758 | |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 759 | static int qcow_write(BlockDriverState *bs, int64_t sector_num, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 760 | const uint8_t *buf, int nb_sectors) |
| 761 | { |
| 762 | BDRVQcowState *s = bs->opaque; |
| 763 | int ret, index_in_cluster, n; |
| 764 | uint64_t cluster_offset; |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 765 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 766 | while (nb_sectors > 0) { |
| 767 | index_in_cluster = sector_num & (s->cluster_sectors - 1); |
| 768 | n = s->cluster_sectors - index_in_cluster; |
| 769 | if (n > nb_sectors) |
| 770 | n = nb_sectors; |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 771 | cluster_offset = get_cluster_offset(bs, sector_num << 9, 1, 0, |
| 772 | index_in_cluster, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 773 | index_in_cluster + n); |
| 774 | if (!cluster_offset) |
| 775 | return -1; |
| 776 | if (s->crypt_method) { |
| 777 | encrypt_sectors(s, sector_num, s->cluster_data, buf, n, 1, |
| 778 | &s->aes_encrypt_key); |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 779 | ret = bdrv_pwrite(s->hd, cluster_offset + index_in_cluster * 512, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 780 | s->cluster_data, n * 512); |
| 781 | } else { |
| 782 | ret = bdrv_pwrite(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512); |
| 783 | } |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 784 | if (ret != n * 512) |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 785 | return -1; |
| 786 | nb_sectors -= n; |
| 787 | sector_num += n; |
| 788 | buf += n * 512; |
| 789 | } |
| 790 | s->cluster_cache_offset = -1; /* disable compressed cache */ |
| 791 | return 0; |
| 792 | } |
| 793 | |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 794 | typedef struct QCowAIOCB { |
| 795 | BlockDriverAIOCB common; |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 796 | int64_t sector_num; |
| 797 | uint8_t *buf; |
| 798 | int nb_sectors; |
| 799 | int n; |
| 800 | uint64_t cluster_offset; |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 801 | uint8_t *cluster_data; |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 802 | BlockDriverAIOCB *hd_aiocb; |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 803 | } QCowAIOCB; |
| 804 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 805 | static void qcow_aio_read_cb(void *opaque, int ret) |
| 806 | { |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 807 | QCowAIOCB *acb = opaque; |
| 808 | BlockDriverState *bs = acb->common.bs; |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 809 | BDRVQcowState *s = bs->opaque; |
bellard | a946592 | 2006-08-06 13:34:04 +0000 | [diff] [blame] | 810 | int index_in_cluster, n1; |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 811 | |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 812 | acb->hd_aiocb = NULL; |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 813 | if (ret < 0) { |
| 814 | fail: |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 815 | acb->common.cb(acb->common.opaque, ret); |
| 816 | qemu_aio_release(acb); |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 817 | return; |
| 818 | } |
| 819 | |
| 820 | redo: |
| 821 | /* post process the read buffer */ |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 822 | if (!acb->cluster_offset) { |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 823 | /* nothing to do */ |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 824 | } else if (acb->cluster_offset & QCOW_OFLAG_COMPRESSED) { |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 825 | /* nothing to do */ |
| 826 | } else { |
| 827 | if (s->crypt_method) { |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 828 | encrypt_sectors(s, acb->sector_num, acb->buf, acb->buf, |
| 829 | acb->n, 0, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 830 | &s->aes_decrypt_key); |
| 831 | } |
| 832 | } |
| 833 | |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 834 | acb->nb_sectors -= acb->n; |
| 835 | acb->sector_num += acb->n; |
| 836 | acb->buf += acb->n * 512; |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 837 | |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 838 | if (acb->nb_sectors == 0) { |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 839 | /* request completed */ |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 840 | acb->common.cb(acb->common.opaque, 0); |
| 841 | qemu_aio_release(acb); |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 842 | return; |
| 843 | } |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 844 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 845 | /* prepare next AIO request */ |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 846 | acb->cluster_offset = get_cluster_offset(bs, acb->sector_num << 9, |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 847 | 0, 0, 0, 0); |
| 848 | index_in_cluster = acb->sector_num & (s->cluster_sectors - 1); |
| 849 | acb->n = s->cluster_sectors - index_in_cluster; |
| 850 | if (acb->n > acb->nb_sectors) |
| 851 | acb->n = acb->nb_sectors; |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 852 | |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 853 | if (!acb->cluster_offset) { |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 854 | if (bs->backing_hd) { |
| 855 | /* read from the base image */ |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 856 | n1 = backing_read1(bs->backing_hd, acb->sector_num, |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 857 | acb->buf, acb->n); |
bellard | a946592 | 2006-08-06 13:34:04 +0000 | [diff] [blame] | 858 | if (n1 > 0) { |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 859 | acb->hd_aiocb = bdrv_aio_read(bs->backing_hd, acb->sector_num, |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 860 | acb->buf, acb->n, qcow_aio_read_cb, acb); |
| 861 | if (acb->hd_aiocb == NULL) |
bellard | a946592 | 2006-08-06 13:34:04 +0000 | [diff] [blame] | 862 | goto fail; |
| 863 | } else { |
| 864 | goto redo; |
| 865 | } |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 866 | } else { |
| 867 | /* Note: in this case, no need to wait */ |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 868 | memset(acb->buf, 0, 512 * acb->n); |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 869 | goto redo; |
| 870 | } |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 871 | } else if (acb->cluster_offset & QCOW_OFLAG_COMPRESSED) { |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 872 | /* add AIO support for compressed blocks ? */ |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 873 | if (decompress_cluster(s, acb->cluster_offset) < 0) |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 874 | goto fail; |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 875 | memcpy(acb->buf, |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 876 | s->cluster_cache + index_in_cluster * 512, 512 * acb->n); |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 877 | goto redo; |
| 878 | } else { |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 879 | if ((acb->cluster_offset & 511) != 0) { |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 880 | ret = -EIO; |
| 881 | goto fail; |
| 882 | } |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 883 | acb->hd_aiocb = bdrv_aio_read(s->hd, |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 884 | (acb->cluster_offset >> 9) + index_in_cluster, |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 885 | acb->buf, acb->n, qcow_aio_read_cb, acb); |
| 886 | if (acb->hd_aiocb == NULL) |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 887 | goto fail; |
| 888 | } |
| 889 | } |
| 890 | |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 891 | static QCowAIOCB *qcow_aio_setup(BlockDriverState *bs, |
| 892 | int64_t sector_num, uint8_t *buf, int nb_sectors, |
| 893 | BlockDriverCompletionFunc *cb, void *opaque) |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 894 | { |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 895 | QCowAIOCB *acb; |
| 896 | |
| 897 | acb = qemu_aio_get(bs, cb, opaque); |
| 898 | if (!acb) |
| 899 | return NULL; |
| 900 | acb->hd_aiocb = NULL; |
| 901 | acb->sector_num = sector_num; |
| 902 | acb->buf = buf; |
| 903 | acb->nb_sectors = nb_sectors; |
| 904 | acb->n = 0; |
| 905 | acb->cluster_offset = 0; |
| 906 | return acb; |
| 907 | } |
| 908 | |
| 909 | static BlockDriverAIOCB *qcow_aio_read(BlockDriverState *bs, |
| 910 | int64_t sector_num, uint8_t *buf, int nb_sectors, |
| 911 | BlockDriverCompletionFunc *cb, void *opaque) |
| 912 | { |
| 913 | QCowAIOCB *acb; |
| 914 | |
| 915 | acb = qcow_aio_setup(bs, sector_num, buf, nb_sectors, cb, opaque); |
| 916 | if (!acb) |
| 917 | return NULL; |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 918 | |
| 919 | qcow_aio_read_cb(acb, 0); |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 920 | return &acb->common; |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 921 | } |
| 922 | |
| 923 | static void qcow_aio_write_cb(void *opaque, int ret) |
| 924 | { |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 925 | QCowAIOCB *acb = opaque; |
| 926 | BlockDriverState *bs = acb->common.bs; |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 927 | BDRVQcowState *s = bs->opaque; |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 928 | int index_in_cluster; |
| 929 | uint64_t cluster_offset; |
| 930 | const uint8_t *src_buf; |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 931 | |
| 932 | acb->hd_aiocb = NULL; |
| 933 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 934 | if (ret < 0) { |
| 935 | fail: |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 936 | acb->common.cb(acb->common.opaque, ret); |
| 937 | qemu_aio_release(acb); |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 938 | return; |
| 939 | } |
| 940 | |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 941 | acb->nb_sectors -= acb->n; |
| 942 | acb->sector_num += acb->n; |
| 943 | acb->buf += acb->n * 512; |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 944 | |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 945 | if (acb->nb_sectors == 0) { |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 946 | /* request completed */ |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 947 | acb->common.cb(acb->common.opaque, 0); |
| 948 | qemu_aio_release(acb); |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 949 | return; |
| 950 | } |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 951 | |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 952 | index_in_cluster = acb->sector_num & (s->cluster_sectors - 1); |
| 953 | acb->n = s->cluster_sectors - index_in_cluster; |
| 954 | if (acb->n > acb->nb_sectors) |
| 955 | acb->n = acb->nb_sectors; |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 956 | cluster_offset = get_cluster_offset(bs, acb->sector_num << 9, 1, 0, |
| 957 | index_in_cluster, |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 958 | index_in_cluster + acb->n); |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 959 | if (!cluster_offset || (cluster_offset & 511) != 0) { |
| 960 | ret = -EIO; |
| 961 | goto fail; |
| 962 | } |
| 963 | if (s->crypt_method) { |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 964 | if (!acb->cluster_data) { |
| 965 | acb->cluster_data = qemu_mallocz(s->cluster_size); |
| 966 | if (!acb->cluster_data) { |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 967 | ret = -ENOMEM; |
| 968 | goto fail; |
| 969 | } |
| 970 | } |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 971 | encrypt_sectors(s, acb->sector_num, acb->cluster_data, acb->buf, |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 972 | acb->n, 1, &s->aes_encrypt_key); |
| 973 | src_buf = acb->cluster_data; |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 974 | } else { |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 975 | src_buf = acb->buf; |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 976 | } |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 977 | acb->hd_aiocb = bdrv_aio_write(s->hd, |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 978 | (cluster_offset >> 9) + index_in_cluster, |
| 979 | src_buf, acb->n, |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 980 | qcow_aio_write_cb, acb); |
| 981 | if (acb->hd_aiocb == NULL) |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 982 | goto fail; |
| 983 | } |
| 984 | |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 985 | static BlockDriverAIOCB *qcow_aio_write(BlockDriverState *bs, |
| 986 | int64_t sector_num, const uint8_t *buf, int nb_sectors, |
| 987 | BlockDriverCompletionFunc *cb, void *opaque) |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 988 | { |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 989 | BDRVQcowState *s = bs->opaque; |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 990 | QCowAIOCB *acb; |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 991 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 992 | s->cluster_cache_offset = -1; /* disable compressed cache */ |
| 993 | |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 994 | acb = qcow_aio_setup(bs, sector_num, (uint8_t*)buf, nb_sectors, cb, opaque); |
| 995 | if (!acb) |
| 996 | return NULL; |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 997 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 998 | qcow_aio_write_cb(acb, 0); |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 999 | return &acb->common; |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1000 | } |
| 1001 | |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 1002 | static void qcow_aio_cancel(BlockDriverAIOCB *blockacb) |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1003 | { |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 1004 | QCowAIOCB *acb = (QCowAIOCB *)blockacb; |
| 1005 | if (acb->hd_aiocb) |
| 1006 | bdrv_aio_cancel(acb->hd_aiocb); |
| 1007 | qemu_aio_release(acb); |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1008 | } |
| 1009 | |
| 1010 | static void qcow_close(BlockDriverState *bs) |
| 1011 | { |
| 1012 | BDRVQcowState *s = bs->opaque; |
| 1013 | qemu_free(s->l1_table); |
| 1014 | qemu_free(s->l2_cache); |
| 1015 | qemu_free(s->cluster_cache); |
| 1016 | qemu_free(s->cluster_data); |
| 1017 | refcount_close(bs); |
| 1018 | bdrv_delete(s->hd); |
| 1019 | } |
| 1020 | |
| 1021 | /* XXX: use std qcow open function ? */ |
| 1022 | typedef struct QCowCreateState { |
| 1023 | int cluster_size; |
| 1024 | int cluster_bits; |
| 1025 | uint16_t *refcount_block; |
| 1026 | uint64_t *refcount_table; |
| 1027 | int64_t l1_table_offset; |
| 1028 | int64_t refcount_table_offset; |
| 1029 | int64_t refcount_block_offset; |
| 1030 | } QCowCreateState; |
| 1031 | |
| 1032 | static void create_refcount_update(QCowCreateState *s, |
| 1033 | int64_t offset, int64_t size) |
| 1034 | { |
| 1035 | int refcount; |
| 1036 | int64_t start, last, cluster_offset; |
| 1037 | uint16_t *p; |
| 1038 | |
| 1039 | start = offset & ~(s->cluster_size - 1); |
| 1040 | last = (offset + size - 1) & ~(s->cluster_size - 1); |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1041 | for(cluster_offset = start; cluster_offset <= last; |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1042 | cluster_offset += s->cluster_size) { |
| 1043 | p = &s->refcount_block[cluster_offset >> s->cluster_bits]; |
| 1044 | refcount = be16_to_cpu(*p); |
| 1045 | refcount++; |
| 1046 | *p = cpu_to_be16(refcount); |
| 1047 | } |
| 1048 | } |
| 1049 | |
| 1050 | static int qcow_create(const char *filename, int64_t total_size, |
| 1051 | const char *backing_file, int flags) |
| 1052 | { |
| 1053 | int fd, header_size, backing_filename_len, l1_size, i, shift, l2_bits; |
| 1054 | QCowHeader header; |
| 1055 | uint64_t tmp, offset; |
| 1056 | QCowCreateState s1, *s = &s1; |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 1057 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1058 | memset(s, 0, sizeof(*s)); |
| 1059 | |
| 1060 | fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, 0644); |
| 1061 | if (fd < 0) |
| 1062 | return -1; |
| 1063 | memset(&header, 0, sizeof(header)); |
| 1064 | header.magic = cpu_to_be32(QCOW_MAGIC); |
| 1065 | header.version = cpu_to_be32(QCOW_VERSION); |
| 1066 | header.size = cpu_to_be64(total_size * 512); |
| 1067 | header_size = sizeof(header); |
| 1068 | backing_filename_len = 0; |
| 1069 | if (backing_file) { |
| 1070 | header.backing_file_offset = cpu_to_be64(header_size); |
| 1071 | backing_filename_len = strlen(backing_file); |
| 1072 | header.backing_file_size = cpu_to_be32(backing_filename_len); |
| 1073 | header_size += backing_filename_len; |
| 1074 | } |
| 1075 | s->cluster_bits = 12; /* 4 KB clusters */ |
| 1076 | s->cluster_size = 1 << s->cluster_bits; |
| 1077 | header.cluster_bits = cpu_to_be32(s->cluster_bits); |
| 1078 | header_size = (header_size + 7) & ~7; |
ths | ec36ba1 | 2007-09-16 21:59:02 +0000 | [diff] [blame] | 1079 | if (flags & BLOCK_FLAG_ENCRYPT) { |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1080 | header.crypt_method = cpu_to_be32(QCOW_CRYPT_AES); |
| 1081 | } else { |
| 1082 | header.crypt_method = cpu_to_be32(QCOW_CRYPT_NONE); |
| 1083 | } |
| 1084 | l2_bits = s->cluster_bits - 3; |
| 1085 | shift = s->cluster_bits + l2_bits; |
| 1086 | l1_size = (((total_size * 512) + (1LL << shift) - 1) >> shift); |
| 1087 | offset = align_offset(header_size, s->cluster_size); |
| 1088 | s->l1_table_offset = offset; |
| 1089 | header.l1_table_offset = cpu_to_be64(s->l1_table_offset); |
| 1090 | header.l1_size = cpu_to_be32(l1_size); |
bellard | 15e6690 | 2006-08-05 22:24:28 +0000 | [diff] [blame] | 1091 | offset += align_offset(l1_size * sizeof(uint64_t), s->cluster_size); |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1092 | |
| 1093 | s->refcount_table = qemu_mallocz(s->cluster_size); |
| 1094 | if (!s->refcount_table) |
| 1095 | goto fail; |
| 1096 | s->refcount_block = qemu_mallocz(s->cluster_size); |
| 1097 | if (!s->refcount_block) |
| 1098 | goto fail; |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 1099 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1100 | s->refcount_table_offset = offset; |
| 1101 | header.refcount_table_offset = cpu_to_be64(offset); |
| 1102 | header.refcount_table_clusters = cpu_to_be32(1); |
| 1103 | offset += s->cluster_size; |
| 1104 | |
| 1105 | s->refcount_table[0] = cpu_to_be64(offset); |
| 1106 | s->refcount_block_offset = offset; |
| 1107 | offset += s->cluster_size; |
| 1108 | |
| 1109 | /* update refcounts */ |
| 1110 | create_refcount_update(s, 0, header_size); |
bellard | 15e6690 | 2006-08-05 22:24:28 +0000 | [diff] [blame] | 1111 | create_refcount_update(s, s->l1_table_offset, l1_size * sizeof(uint64_t)); |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1112 | create_refcount_update(s, s->refcount_table_offset, s->cluster_size); |
| 1113 | create_refcount_update(s, s->refcount_block_offset, s->cluster_size); |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 1114 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1115 | /* write all the data */ |
| 1116 | write(fd, &header, sizeof(header)); |
| 1117 | if (backing_file) { |
| 1118 | write(fd, backing_file, backing_filename_len); |
| 1119 | } |
| 1120 | lseek(fd, s->l1_table_offset, SEEK_SET); |
| 1121 | tmp = 0; |
| 1122 | for(i = 0;i < l1_size; i++) { |
| 1123 | write(fd, &tmp, sizeof(tmp)); |
| 1124 | } |
| 1125 | lseek(fd, s->refcount_table_offset, SEEK_SET); |
| 1126 | write(fd, s->refcount_table, s->cluster_size); |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 1127 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1128 | lseek(fd, s->refcount_block_offset, SEEK_SET); |
| 1129 | write(fd, s->refcount_block, s->cluster_size); |
| 1130 | |
| 1131 | qemu_free(s->refcount_table); |
| 1132 | qemu_free(s->refcount_block); |
| 1133 | close(fd); |
| 1134 | return 0; |
| 1135 | fail: |
| 1136 | qemu_free(s->refcount_table); |
| 1137 | qemu_free(s->refcount_block); |
| 1138 | close(fd); |
| 1139 | return -ENOMEM; |
| 1140 | } |
| 1141 | |
| 1142 | static int qcow_make_empty(BlockDriverState *bs) |
| 1143 | { |
| 1144 | #if 0 |
| 1145 | /* XXX: not correct */ |
| 1146 | BDRVQcowState *s = bs->opaque; |
| 1147 | uint32_t l1_length = s->l1_size * sizeof(uint64_t); |
| 1148 | int ret; |
| 1149 | |
| 1150 | memset(s->l1_table, 0, l1_length); |
| 1151 | if (bdrv_pwrite(s->hd, s->l1_table_offset, s->l1_table, l1_length) < 0) |
| 1152 | return -1; |
| 1153 | ret = bdrv_truncate(s->hd, s->l1_table_offset + l1_length); |
| 1154 | if (ret < 0) |
| 1155 | return ret; |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 1156 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1157 | l2_cache_reset(bs); |
| 1158 | #endif |
| 1159 | return 0; |
| 1160 | } |
| 1161 | |
| 1162 | /* XXX: put compressed sectors first, then all the cluster aligned |
| 1163 | tables to avoid losing bytes in alignment */ |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1164 | static int qcow_write_compressed(BlockDriverState *bs, int64_t sector_num, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1165 | const uint8_t *buf, int nb_sectors) |
| 1166 | { |
| 1167 | BDRVQcowState *s = bs->opaque; |
| 1168 | z_stream strm; |
| 1169 | int ret, out_len; |
| 1170 | uint8_t *out_buf; |
| 1171 | uint64_t cluster_offset; |
| 1172 | |
| 1173 | if (nb_sectors == 0) { |
| 1174 | /* align end of file to a sector boundary to ease reading with |
| 1175 | sector based I/Os */ |
| 1176 | cluster_offset = bdrv_getlength(s->hd); |
| 1177 | cluster_offset = (cluster_offset + 511) & ~511; |
| 1178 | bdrv_truncate(s->hd, cluster_offset); |
| 1179 | return 0; |
| 1180 | } |
| 1181 | |
| 1182 | if (nb_sectors != s->cluster_sectors) |
| 1183 | return -EINVAL; |
| 1184 | |
| 1185 | out_buf = qemu_malloc(s->cluster_size + (s->cluster_size / 1000) + 128); |
| 1186 | if (!out_buf) |
| 1187 | return -ENOMEM; |
| 1188 | |
| 1189 | /* best compression, small window, no zlib header */ |
| 1190 | memset(&strm, 0, sizeof(strm)); |
| 1191 | ret = deflateInit2(&strm, Z_DEFAULT_COMPRESSION, |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1192 | Z_DEFLATED, -12, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1193 | 9, Z_DEFAULT_STRATEGY); |
| 1194 | if (ret != 0) { |
| 1195 | qemu_free(out_buf); |
| 1196 | return -1; |
| 1197 | } |
| 1198 | |
| 1199 | strm.avail_in = s->cluster_size; |
| 1200 | strm.next_in = (uint8_t *)buf; |
| 1201 | strm.avail_out = s->cluster_size; |
| 1202 | strm.next_out = out_buf; |
| 1203 | |
| 1204 | ret = deflate(&strm, Z_FINISH); |
| 1205 | if (ret != Z_STREAM_END && ret != Z_OK) { |
| 1206 | qemu_free(out_buf); |
| 1207 | deflateEnd(&strm); |
| 1208 | return -1; |
| 1209 | } |
| 1210 | out_len = strm.next_out - out_buf; |
| 1211 | |
| 1212 | deflateEnd(&strm); |
| 1213 | |
| 1214 | if (ret != Z_STREAM_END || out_len >= s->cluster_size) { |
| 1215 | /* could not compress: write normal cluster */ |
| 1216 | qcow_write(bs, sector_num, buf, s->cluster_sectors); |
| 1217 | } else { |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1218 | cluster_offset = get_cluster_offset(bs, sector_num << 9, 2, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1219 | out_len, 0, 0); |
| 1220 | cluster_offset &= s->cluster_offset_mask; |
| 1221 | if (bdrv_pwrite(s->hd, cluster_offset, out_buf, out_len) != out_len) { |
| 1222 | qemu_free(out_buf); |
| 1223 | return -1; |
| 1224 | } |
| 1225 | } |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 1226 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1227 | qemu_free(out_buf); |
| 1228 | return 0; |
| 1229 | } |
| 1230 | |
| 1231 | static void qcow_flush(BlockDriverState *bs) |
| 1232 | { |
| 1233 | BDRVQcowState *s = bs->opaque; |
| 1234 | bdrv_flush(s->hd); |
| 1235 | } |
| 1236 | |
| 1237 | static int qcow_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) |
| 1238 | { |
| 1239 | BDRVQcowState *s = bs->opaque; |
| 1240 | bdi->cluster_size = s->cluster_size; |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1241 | bdi->vm_state_offset = (int64_t)s->l1_vm_state_index << |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1242 | (s->cluster_bits + s->l2_bits); |
| 1243 | return 0; |
| 1244 | } |
| 1245 | |
| 1246 | /*********************************************************/ |
| 1247 | /* snapshot support */ |
| 1248 | |
| 1249 | /* update the refcounts of snapshots and the copied flag */ |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1250 | static int update_snapshot_refcount(BlockDriverState *bs, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1251 | int64_t l1_table_offset, |
| 1252 | int l1_size, |
| 1253 | int addend) |
| 1254 | { |
| 1255 | BDRVQcowState *s = bs->opaque; |
| 1256 | uint64_t *l1_table, *l2_table, l2_offset, offset, l1_size2, l1_allocated; |
| 1257 | int64_t old_offset, old_l2_offset; |
| 1258 | int l2_size, i, j, l1_modified, l2_modified, nb_csectors, refcount; |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 1259 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1260 | l2_cache_reset(bs); |
| 1261 | |
| 1262 | l2_table = NULL; |
| 1263 | l1_table = NULL; |
| 1264 | l1_size2 = l1_size * sizeof(uint64_t); |
| 1265 | l1_allocated = 0; |
| 1266 | if (l1_table_offset != s->l1_table_offset) { |
| 1267 | l1_table = qemu_malloc(l1_size2); |
| 1268 | if (!l1_table) |
| 1269 | goto fail; |
| 1270 | l1_allocated = 1; |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1271 | if (bdrv_pread(s->hd, l1_table_offset, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1272 | l1_table, l1_size2) != l1_size2) |
| 1273 | goto fail; |
| 1274 | for(i = 0;i < l1_size; i++) |
| 1275 | be64_to_cpus(&l1_table[i]); |
| 1276 | } else { |
| 1277 | assert(l1_size == s->l1_size); |
| 1278 | l1_table = s->l1_table; |
| 1279 | l1_allocated = 0; |
| 1280 | } |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 1281 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1282 | l2_size = s->l2_size * sizeof(uint64_t); |
| 1283 | l2_table = qemu_malloc(l2_size); |
| 1284 | if (!l2_table) |
| 1285 | goto fail; |
| 1286 | l1_modified = 0; |
| 1287 | for(i = 0; i < l1_size; i++) { |
| 1288 | l2_offset = l1_table[i]; |
| 1289 | if (l2_offset) { |
| 1290 | old_l2_offset = l2_offset; |
| 1291 | l2_offset &= ~QCOW_OFLAG_COPIED; |
| 1292 | l2_modified = 0; |
| 1293 | if (bdrv_pread(s->hd, l2_offset, l2_table, l2_size) != l2_size) |
| 1294 | goto fail; |
| 1295 | for(j = 0; j < s->l2_size; j++) { |
| 1296 | offset = be64_to_cpu(l2_table[j]); |
| 1297 | if (offset != 0) { |
| 1298 | old_offset = offset; |
| 1299 | offset &= ~QCOW_OFLAG_COPIED; |
| 1300 | if (offset & QCOW_OFLAG_COMPRESSED) { |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1301 | nb_csectors = ((offset >> s->csize_shift) & |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1302 | s->csize_mask) + 1; |
| 1303 | if (addend != 0) |
| 1304 | update_refcount(bs, (offset & s->cluster_offset_mask) & ~511, |
| 1305 | nb_csectors * 512, addend); |
| 1306 | /* compressed clusters are never modified */ |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1307 | refcount = 2; |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1308 | } else { |
| 1309 | if (addend != 0) { |
| 1310 | refcount = update_cluster_refcount(bs, offset >> s->cluster_bits, addend); |
| 1311 | } else { |
| 1312 | refcount = get_refcount(bs, offset >> s->cluster_bits); |
| 1313 | } |
| 1314 | } |
| 1315 | |
| 1316 | if (refcount == 1) { |
| 1317 | offset |= QCOW_OFLAG_COPIED; |
| 1318 | } |
| 1319 | if (offset != old_offset) { |
| 1320 | l2_table[j] = cpu_to_be64(offset); |
| 1321 | l2_modified = 1; |
| 1322 | } |
| 1323 | } |
| 1324 | } |
| 1325 | if (l2_modified) { |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1326 | if (bdrv_pwrite(s->hd, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1327 | l2_offset, l2_table, l2_size) != l2_size) |
| 1328 | goto fail; |
| 1329 | } |
| 1330 | |
| 1331 | if (addend != 0) { |
| 1332 | refcount = update_cluster_refcount(bs, l2_offset >> s->cluster_bits, addend); |
| 1333 | } else { |
| 1334 | refcount = get_refcount(bs, l2_offset >> s->cluster_bits); |
| 1335 | } |
| 1336 | if (refcount == 1) { |
| 1337 | l2_offset |= QCOW_OFLAG_COPIED; |
| 1338 | } |
| 1339 | if (l2_offset != old_l2_offset) { |
| 1340 | l1_table[i] = l2_offset; |
| 1341 | l1_modified = 1; |
| 1342 | } |
| 1343 | } |
| 1344 | } |
| 1345 | if (l1_modified) { |
| 1346 | for(i = 0; i < l1_size; i++) |
| 1347 | cpu_to_be64s(&l1_table[i]); |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1348 | if (bdrv_pwrite(s->hd, l1_table_offset, l1_table, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1349 | l1_size2) != l1_size2) |
| 1350 | goto fail; |
| 1351 | for(i = 0; i < l1_size; i++) |
| 1352 | be64_to_cpus(&l1_table[i]); |
| 1353 | } |
| 1354 | if (l1_allocated) |
| 1355 | qemu_free(l1_table); |
| 1356 | qemu_free(l2_table); |
| 1357 | return 0; |
| 1358 | fail: |
| 1359 | if (l1_allocated) |
| 1360 | qemu_free(l1_table); |
| 1361 | qemu_free(l2_table); |
| 1362 | return -EIO; |
| 1363 | } |
| 1364 | |
| 1365 | static void qcow_free_snapshots(BlockDriverState *bs) |
| 1366 | { |
| 1367 | BDRVQcowState *s = bs->opaque; |
| 1368 | int i; |
| 1369 | |
| 1370 | for(i = 0; i < s->nb_snapshots; i++) { |
| 1371 | qemu_free(s->snapshots[i].name); |
| 1372 | qemu_free(s->snapshots[i].id_str); |
| 1373 | } |
| 1374 | qemu_free(s->snapshots); |
| 1375 | s->snapshots = NULL; |
| 1376 | s->nb_snapshots = 0; |
| 1377 | } |
| 1378 | |
| 1379 | static int qcow_read_snapshots(BlockDriverState *bs) |
| 1380 | { |
| 1381 | BDRVQcowState *s = bs->opaque; |
| 1382 | QCowSnapshotHeader h; |
| 1383 | QCowSnapshot *sn; |
| 1384 | int i, id_str_size, name_size; |
| 1385 | int64_t offset; |
| 1386 | uint32_t extra_data_size; |
| 1387 | |
| 1388 | offset = s->snapshots_offset; |
| 1389 | s->snapshots = qemu_mallocz(s->nb_snapshots * sizeof(QCowSnapshot)); |
| 1390 | if (!s->snapshots) |
| 1391 | goto fail; |
| 1392 | for(i = 0; i < s->nb_snapshots; i++) { |
| 1393 | offset = align_offset(offset, 8); |
| 1394 | if (bdrv_pread(s->hd, offset, &h, sizeof(h)) != sizeof(h)) |
| 1395 | goto fail; |
| 1396 | offset += sizeof(h); |
| 1397 | sn = s->snapshots + i; |
| 1398 | sn->l1_table_offset = be64_to_cpu(h.l1_table_offset); |
| 1399 | sn->l1_size = be32_to_cpu(h.l1_size); |
| 1400 | sn->vm_state_size = be32_to_cpu(h.vm_state_size); |
| 1401 | sn->date_sec = be32_to_cpu(h.date_sec); |
| 1402 | sn->date_nsec = be32_to_cpu(h.date_nsec); |
| 1403 | sn->vm_clock_nsec = be64_to_cpu(h.vm_clock_nsec); |
| 1404 | extra_data_size = be32_to_cpu(h.extra_data_size); |
| 1405 | |
| 1406 | id_str_size = be16_to_cpu(h.id_str_size); |
| 1407 | name_size = be16_to_cpu(h.name_size); |
| 1408 | |
| 1409 | offset += extra_data_size; |
| 1410 | |
| 1411 | sn->id_str = qemu_malloc(id_str_size + 1); |
| 1412 | if (!sn->id_str) |
| 1413 | goto fail; |
| 1414 | if (bdrv_pread(s->hd, offset, sn->id_str, id_str_size) != id_str_size) |
| 1415 | goto fail; |
| 1416 | offset += id_str_size; |
| 1417 | sn->id_str[id_str_size] = '\0'; |
| 1418 | |
| 1419 | sn->name = qemu_malloc(name_size + 1); |
| 1420 | if (!sn->name) |
| 1421 | goto fail; |
| 1422 | if (bdrv_pread(s->hd, offset, sn->name, name_size) != name_size) |
| 1423 | goto fail; |
| 1424 | offset += name_size; |
| 1425 | sn->name[name_size] = '\0'; |
| 1426 | } |
| 1427 | s->snapshots_size = offset - s->snapshots_offset; |
| 1428 | return 0; |
| 1429 | fail: |
| 1430 | qcow_free_snapshots(bs); |
| 1431 | return -1; |
| 1432 | } |
| 1433 | |
| 1434 | /* add at the end of the file a new list of snapshots */ |
| 1435 | static int qcow_write_snapshots(BlockDriverState *bs) |
| 1436 | { |
| 1437 | BDRVQcowState *s = bs->opaque; |
| 1438 | QCowSnapshot *sn; |
| 1439 | QCowSnapshotHeader h; |
| 1440 | int i, name_size, id_str_size, snapshots_size; |
| 1441 | uint64_t data64; |
| 1442 | uint32_t data32; |
| 1443 | int64_t offset, snapshots_offset; |
| 1444 | |
| 1445 | /* compute the size of the snapshots */ |
| 1446 | offset = 0; |
| 1447 | for(i = 0; i < s->nb_snapshots; i++) { |
| 1448 | sn = s->snapshots + i; |
| 1449 | offset = align_offset(offset, 8); |
| 1450 | offset += sizeof(h); |
| 1451 | offset += strlen(sn->id_str); |
| 1452 | offset += strlen(sn->name); |
| 1453 | } |
| 1454 | snapshots_size = offset; |
| 1455 | |
| 1456 | snapshots_offset = alloc_clusters(bs, snapshots_size); |
| 1457 | offset = snapshots_offset; |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 1458 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1459 | for(i = 0; i < s->nb_snapshots; i++) { |
| 1460 | sn = s->snapshots + i; |
| 1461 | memset(&h, 0, sizeof(h)); |
| 1462 | h.l1_table_offset = cpu_to_be64(sn->l1_table_offset); |
| 1463 | h.l1_size = cpu_to_be32(sn->l1_size); |
| 1464 | h.vm_state_size = cpu_to_be32(sn->vm_state_size); |
| 1465 | h.date_sec = cpu_to_be32(sn->date_sec); |
| 1466 | h.date_nsec = cpu_to_be32(sn->date_nsec); |
| 1467 | h.vm_clock_nsec = cpu_to_be64(sn->vm_clock_nsec); |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 1468 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1469 | id_str_size = strlen(sn->id_str); |
| 1470 | name_size = strlen(sn->name); |
| 1471 | h.id_str_size = cpu_to_be16(id_str_size); |
| 1472 | h.name_size = cpu_to_be16(name_size); |
| 1473 | offset = align_offset(offset, 8); |
| 1474 | if (bdrv_pwrite(s->hd, offset, &h, sizeof(h)) != sizeof(h)) |
| 1475 | goto fail; |
| 1476 | offset += sizeof(h); |
| 1477 | if (bdrv_pwrite(s->hd, offset, sn->id_str, id_str_size) != id_str_size) |
| 1478 | goto fail; |
| 1479 | offset += id_str_size; |
| 1480 | if (bdrv_pwrite(s->hd, offset, sn->name, name_size) != name_size) |
| 1481 | goto fail; |
| 1482 | offset += name_size; |
| 1483 | } |
| 1484 | |
| 1485 | /* update the various header fields */ |
| 1486 | data64 = cpu_to_be64(snapshots_offset); |
| 1487 | if (bdrv_pwrite(s->hd, offsetof(QCowHeader, snapshots_offset), |
| 1488 | &data64, sizeof(data64)) != sizeof(data64)) |
| 1489 | goto fail; |
| 1490 | data32 = cpu_to_be32(s->nb_snapshots); |
| 1491 | if (bdrv_pwrite(s->hd, offsetof(QCowHeader, nb_snapshots), |
| 1492 | &data32, sizeof(data32)) != sizeof(data32)) |
| 1493 | goto fail; |
| 1494 | |
| 1495 | /* free the old snapshot table */ |
| 1496 | free_clusters(bs, s->snapshots_offset, s->snapshots_size); |
| 1497 | s->snapshots_offset = snapshots_offset; |
| 1498 | s->snapshots_size = snapshots_size; |
| 1499 | return 0; |
| 1500 | fail: |
| 1501 | return -1; |
| 1502 | } |
| 1503 | |
| 1504 | static void find_new_snapshot_id(BlockDriverState *bs, |
| 1505 | char *id_str, int id_str_size) |
| 1506 | { |
| 1507 | BDRVQcowState *s = bs->opaque; |
| 1508 | QCowSnapshot *sn; |
| 1509 | int i, id, id_max = 0; |
| 1510 | |
| 1511 | for(i = 0; i < s->nb_snapshots; i++) { |
| 1512 | sn = s->snapshots + i; |
| 1513 | id = strtoul(sn->id_str, NULL, 10); |
| 1514 | if (id > id_max) |
| 1515 | id_max = id; |
| 1516 | } |
| 1517 | snprintf(id_str, id_str_size, "%d", id_max + 1); |
| 1518 | } |
| 1519 | |
| 1520 | static int find_snapshot_by_id(BlockDriverState *bs, const char *id_str) |
| 1521 | { |
| 1522 | BDRVQcowState *s = bs->opaque; |
| 1523 | int i; |
| 1524 | |
| 1525 | for(i = 0; i < s->nb_snapshots; i++) { |
| 1526 | if (!strcmp(s->snapshots[i].id_str, id_str)) |
| 1527 | return i; |
| 1528 | } |
| 1529 | return -1; |
| 1530 | } |
| 1531 | |
| 1532 | static int find_snapshot_by_id_or_name(BlockDriverState *bs, const char *name) |
| 1533 | { |
| 1534 | BDRVQcowState *s = bs->opaque; |
| 1535 | int i, ret; |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 1536 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1537 | ret = find_snapshot_by_id(bs, name); |
| 1538 | if (ret >= 0) |
| 1539 | return ret; |
| 1540 | for(i = 0; i < s->nb_snapshots; i++) { |
| 1541 | if (!strcmp(s->snapshots[i].name, name)) |
| 1542 | return i; |
| 1543 | } |
| 1544 | return -1; |
| 1545 | } |
| 1546 | |
| 1547 | /* if no id is provided, a new one is constructed */ |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1548 | static int qcow_snapshot_create(BlockDriverState *bs, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1549 | QEMUSnapshotInfo *sn_info) |
| 1550 | { |
| 1551 | BDRVQcowState *s = bs->opaque; |
| 1552 | QCowSnapshot *snapshots1, sn1, *sn = &sn1; |
| 1553 | int i, ret; |
| 1554 | uint64_t *l1_table = NULL; |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 1555 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1556 | memset(sn, 0, sizeof(*sn)); |
| 1557 | |
| 1558 | if (sn_info->id_str[0] == '\0') { |
| 1559 | /* compute a new id */ |
| 1560 | find_new_snapshot_id(bs, sn_info->id_str, sizeof(sn_info->id_str)); |
| 1561 | } |
| 1562 | |
| 1563 | /* check that the ID is unique */ |
| 1564 | if (find_snapshot_by_id(bs, sn_info->id_str) >= 0) |
| 1565 | return -ENOENT; |
| 1566 | |
| 1567 | sn->id_str = qemu_strdup(sn_info->id_str); |
| 1568 | if (!sn->id_str) |
| 1569 | goto fail; |
| 1570 | sn->name = qemu_strdup(sn_info->name); |
| 1571 | if (!sn->name) |
| 1572 | goto fail; |
| 1573 | sn->vm_state_size = sn_info->vm_state_size; |
| 1574 | sn->date_sec = sn_info->date_sec; |
| 1575 | sn->date_nsec = sn_info->date_nsec; |
| 1576 | sn->vm_clock_nsec = sn_info->vm_clock_nsec; |
| 1577 | |
| 1578 | ret = update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 1); |
| 1579 | if (ret < 0) |
| 1580 | goto fail; |
| 1581 | |
| 1582 | /* create the L1 table of the snapshot */ |
| 1583 | sn->l1_table_offset = alloc_clusters(bs, s->l1_size * sizeof(uint64_t)); |
| 1584 | sn->l1_size = s->l1_size; |
| 1585 | |
| 1586 | l1_table = qemu_malloc(s->l1_size * sizeof(uint64_t)); |
| 1587 | if (!l1_table) |
| 1588 | goto fail; |
| 1589 | for(i = 0; i < s->l1_size; i++) { |
| 1590 | l1_table[i] = cpu_to_be64(s->l1_table[i]); |
| 1591 | } |
| 1592 | if (bdrv_pwrite(s->hd, sn->l1_table_offset, |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1593 | l1_table, s->l1_size * sizeof(uint64_t)) != |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1594 | (s->l1_size * sizeof(uint64_t))) |
| 1595 | goto fail; |
| 1596 | qemu_free(l1_table); |
| 1597 | l1_table = NULL; |
| 1598 | |
| 1599 | snapshots1 = qemu_malloc((s->nb_snapshots + 1) * sizeof(QCowSnapshot)); |
| 1600 | if (!snapshots1) |
| 1601 | goto fail; |
| 1602 | memcpy(snapshots1, s->snapshots, s->nb_snapshots * sizeof(QCowSnapshot)); |
| 1603 | s->snapshots = snapshots1; |
| 1604 | s->snapshots[s->nb_snapshots++] = *sn; |
| 1605 | |
| 1606 | if (qcow_write_snapshots(bs) < 0) |
| 1607 | goto fail; |
| 1608 | #ifdef DEBUG_ALLOC |
| 1609 | check_refcounts(bs); |
| 1610 | #endif |
| 1611 | return 0; |
| 1612 | fail: |
| 1613 | qemu_free(sn->name); |
| 1614 | qemu_free(l1_table); |
| 1615 | return -1; |
| 1616 | } |
| 1617 | |
| 1618 | /* copy the snapshot 'snapshot_name' into the current disk image */ |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1619 | static int qcow_snapshot_goto(BlockDriverState *bs, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1620 | const char *snapshot_id) |
| 1621 | { |
| 1622 | BDRVQcowState *s = bs->opaque; |
| 1623 | QCowSnapshot *sn; |
| 1624 | int i, snapshot_index, l1_size2; |
| 1625 | |
| 1626 | snapshot_index = find_snapshot_by_id_or_name(bs, snapshot_id); |
| 1627 | if (snapshot_index < 0) |
| 1628 | return -ENOENT; |
| 1629 | sn = &s->snapshots[snapshot_index]; |
| 1630 | |
| 1631 | if (update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, -1) < 0) |
| 1632 | goto fail; |
| 1633 | |
| 1634 | if (grow_l1_table(bs, sn->l1_size) < 0) |
| 1635 | goto fail; |
| 1636 | |
| 1637 | s->l1_size = sn->l1_size; |
| 1638 | l1_size2 = s->l1_size * sizeof(uint64_t); |
| 1639 | /* copy the snapshot l1 table to the current l1 table */ |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1640 | if (bdrv_pread(s->hd, sn->l1_table_offset, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1641 | s->l1_table, l1_size2) != l1_size2) |
| 1642 | goto fail; |
| 1643 | if (bdrv_pwrite(s->hd, s->l1_table_offset, |
| 1644 | s->l1_table, l1_size2) != l1_size2) |
| 1645 | goto fail; |
| 1646 | for(i = 0;i < s->l1_size; i++) { |
| 1647 | be64_to_cpus(&s->l1_table[i]); |
| 1648 | } |
| 1649 | |
| 1650 | if (update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 1) < 0) |
| 1651 | goto fail; |
| 1652 | |
| 1653 | #ifdef DEBUG_ALLOC |
| 1654 | check_refcounts(bs); |
| 1655 | #endif |
| 1656 | return 0; |
| 1657 | fail: |
| 1658 | return -EIO; |
| 1659 | } |
| 1660 | |
| 1661 | static int qcow_snapshot_delete(BlockDriverState *bs, const char *snapshot_id) |
| 1662 | { |
| 1663 | BDRVQcowState *s = bs->opaque; |
| 1664 | QCowSnapshot *sn; |
| 1665 | int snapshot_index, ret; |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 1666 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1667 | snapshot_index = find_snapshot_by_id_or_name(bs, snapshot_id); |
| 1668 | if (snapshot_index < 0) |
| 1669 | return -ENOENT; |
| 1670 | sn = &s->snapshots[snapshot_index]; |
| 1671 | |
| 1672 | ret = update_snapshot_refcount(bs, sn->l1_table_offset, sn->l1_size, -1); |
| 1673 | if (ret < 0) |
| 1674 | return ret; |
| 1675 | /* must update the copied flag on the current cluster offsets */ |
| 1676 | ret = update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 0); |
| 1677 | if (ret < 0) |
| 1678 | return ret; |
| 1679 | free_clusters(bs, sn->l1_table_offset, sn->l1_size * sizeof(uint64_t)); |
| 1680 | |
| 1681 | qemu_free(sn->id_str); |
| 1682 | qemu_free(sn->name); |
| 1683 | memmove(sn, sn + 1, (s->nb_snapshots - snapshot_index - 1) * sizeof(*sn)); |
| 1684 | s->nb_snapshots--; |
| 1685 | ret = qcow_write_snapshots(bs); |
| 1686 | if (ret < 0) { |
| 1687 | /* XXX: restore snapshot if error ? */ |
| 1688 | return ret; |
| 1689 | } |
| 1690 | #ifdef DEBUG_ALLOC |
| 1691 | check_refcounts(bs); |
| 1692 | #endif |
| 1693 | return 0; |
| 1694 | } |
| 1695 | |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1696 | static int qcow_snapshot_list(BlockDriverState *bs, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1697 | QEMUSnapshotInfo **psn_tab) |
| 1698 | { |
| 1699 | BDRVQcowState *s = bs->opaque; |
| 1700 | QEMUSnapshotInfo *sn_tab, *sn_info; |
| 1701 | QCowSnapshot *sn; |
| 1702 | int i; |
| 1703 | |
| 1704 | sn_tab = qemu_mallocz(s->nb_snapshots * sizeof(QEMUSnapshotInfo)); |
| 1705 | if (!sn_tab) |
| 1706 | goto fail; |
| 1707 | for(i = 0; i < s->nb_snapshots; i++) { |
| 1708 | sn_info = sn_tab + i; |
| 1709 | sn = s->snapshots + i; |
| 1710 | pstrcpy(sn_info->id_str, sizeof(sn_info->id_str), |
| 1711 | sn->id_str); |
| 1712 | pstrcpy(sn_info->name, sizeof(sn_info->name), |
| 1713 | sn->name); |
| 1714 | sn_info->vm_state_size = sn->vm_state_size; |
| 1715 | sn_info->date_sec = sn->date_sec; |
| 1716 | sn_info->date_nsec = sn->date_nsec; |
| 1717 | sn_info->vm_clock_nsec = sn->vm_clock_nsec; |
| 1718 | } |
| 1719 | *psn_tab = sn_tab; |
| 1720 | return s->nb_snapshots; |
| 1721 | fail: |
| 1722 | qemu_free(sn_tab); |
| 1723 | *psn_tab = NULL; |
| 1724 | return -ENOMEM; |
| 1725 | } |
| 1726 | |
| 1727 | /*********************************************************/ |
| 1728 | /* refcount handling */ |
| 1729 | |
| 1730 | static int refcount_init(BlockDriverState *bs) |
| 1731 | { |
| 1732 | BDRVQcowState *s = bs->opaque; |
| 1733 | int ret, refcount_table_size2, i; |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 1734 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1735 | s->refcount_block_cache = qemu_malloc(s->cluster_size); |
| 1736 | if (!s->refcount_block_cache) |
| 1737 | goto fail; |
| 1738 | refcount_table_size2 = s->refcount_table_size * sizeof(uint64_t); |
| 1739 | s->refcount_table = qemu_malloc(refcount_table_size2); |
| 1740 | if (!s->refcount_table) |
| 1741 | goto fail; |
| 1742 | if (s->refcount_table_size > 0) { |
| 1743 | ret = bdrv_pread(s->hd, s->refcount_table_offset, |
| 1744 | s->refcount_table, refcount_table_size2); |
| 1745 | if (ret != refcount_table_size2) |
| 1746 | goto fail; |
| 1747 | for(i = 0; i < s->refcount_table_size; i++) |
| 1748 | be64_to_cpus(&s->refcount_table[i]); |
| 1749 | } |
| 1750 | return 0; |
| 1751 | fail: |
| 1752 | return -ENOMEM; |
| 1753 | } |
| 1754 | |
| 1755 | static void refcount_close(BlockDriverState *bs) |
| 1756 | { |
| 1757 | BDRVQcowState *s = bs->opaque; |
| 1758 | qemu_free(s->refcount_block_cache); |
| 1759 | qemu_free(s->refcount_table); |
| 1760 | } |
| 1761 | |
| 1762 | |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1763 | static int load_refcount_block(BlockDriverState *bs, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1764 | int64_t refcount_block_offset) |
| 1765 | { |
| 1766 | BDRVQcowState *s = bs->opaque; |
| 1767 | int ret; |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1768 | ret = bdrv_pread(s->hd, refcount_block_offset, s->refcount_block_cache, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1769 | s->cluster_size); |
| 1770 | if (ret != s->cluster_size) |
| 1771 | return -EIO; |
| 1772 | s->refcount_block_cache_offset = refcount_block_offset; |
| 1773 | return 0; |
| 1774 | } |
| 1775 | |
| 1776 | static int get_refcount(BlockDriverState *bs, int64_t cluster_index) |
| 1777 | { |
| 1778 | BDRVQcowState *s = bs->opaque; |
| 1779 | int refcount_table_index, block_index; |
| 1780 | int64_t refcount_block_offset; |
| 1781 | |
| 1782 | refcount_table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT); |
| 1783 | if (refcount_table_index >= s->refcount_table_size) |
| 1784 | return 0; |
| 1785 | refcount_block_offset = s->refcount_table[refcount_table_index]; |
| 1786 | if (!refcount_block_offset) |
| 1787 | return 0; |
| 1788 | if (refcount_block_offset != s->refcount_block_cache_offset) { |
| 1789 | /* better than nothing: return allocated if read error */ |
| 1790 | if (load_refcount_block(bs, refcount_block_offset) < 0) |
| 1791 | return 1; |
| 1792 | } |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1793 | block_index = cluster_index & |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1794 | ((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1); |
| 1795 | return be16_to_cpu(s->refcount_block_cache[block_index]); |
| 1796 | } |
| 1797 | |
| 1798 | /* return < 0 if error */ |
| 1799 | static int64_t alloc_clusters_noref(BlockDriverState *bs, int64_t size) |
| 1800 | { |
| 1801 | BDRVQcowState *s = bs->opaque; |
| 1802 | int i, nb_clusters; |
| 1803 | |
| 1804 | nb_clusters = (size + s->cluster_size - 1) >> s->cluster_bits; |
| 1805 | for(;;) { |
| 1806 | if (get_refcount(bs, s->free_cluster_index) == 0) { |
| 1807 | s->free_cluster_index++; |
| 1808 | for(i = 1; i < nb_clusters; i++) { |
| 1809 | if (get_refcount(bs, s->free_cluster_index) != 0) |
| 1810 | goto not_found; |
| 1811 | s->free_cluster_index++; |
| 1812 | } |
| 1813 | #ifdef DEBUG_ALLOC2 |
| 1814 | printf("alloc_clusters: size=%lld -> %lld\n", |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1815 | size, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1816 | (s->free_cluster_index - nb_clusters) << s->cluster_bits); |
| 1817 | #endif |
| 1818 | return (s->free_cluster_index - nb_clusters) << s->cluster_bits; |
| 1819 | } else { |
| 1820 | not_found: |
| 1821 | s->free_cluster_index++; |
| 1822 | } |
| 1823 | } |
| 1824 | } |
| 1825 | |
| 1826 | static int64_t alloc_clusters(BlockDriverState *bs, int64_t size) |
| 1827 | { |
| 1828 | int64_t offset; |
| 1829 | |
| 1830 | offset = alloc_clusters_noref(bs, size); |
| 1831 | update_refcount(bs, offset, size, 1); |
| 1832 | return offset; |
| 1833 | } |
| 1834 | |
| 1835 | /* only used to allocate compressed sectors. We try to allocate |
| 1836 | contiguous sectors. size must be <= cluster_size */ |
| 1837 | static int64_t alloc_bytes(BlockDriverState *bs, int size) |
| 1838 | { |
| 1839 | BDRVQcowState *s = bs->opaque; |
| 1840 | int64_t offset, cluster_offset; |
| 1841 | int free_in_cluster; |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 1842 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1843 | assert(size > 0 && size <= s->cluster_size); |
| 1844 | if (s->free_byte_offset == 0) { |
| 1845 | s->free_byte_offset = alloc_clusters(bs, s->cluster_size); |
| 1846 | } |
| 1847 | redo: |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1848 | free_in_cluster = s->cluster_size - |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1849 | (s->free_byte_offset & (s->cluster_size - 1)); |
| 1850 | if (size <= free_in_cluster) { |
| 1851 | /* enough space in current cluster */ |
| 1852 | offset = s->free_byte_offset; |
| 1853 | s->free_byte_offset += size; |
| 1854 | free_in_cluster -= size; |
| 1855 | if (free_in_cluster == 0) |
| 1856 | s->free_byte_offset = 0; |
| 1857 | if ((offset & (s->cluster_size - 1)) != 0) |
| 1858 | update_cluster_refcount(bs, offset >> s->cluster_bits, 1); |
| 1859 | } else { |
| 1860 | offset = alloc_clusters(bs, s->cluster_size); |
| 1861 | cluster_offset = s->free_byte_offset & ~(s->cluster_size - 1); |
| 1862 | if ((cluster_offset + s->cluster_size) == offset) { |
| 1863 | /* we are lucky: contiguous data */ |
| 1864 | offset = s->free_byte_offset; |
| 1865 | update_cluster_refcount(bs, offset >> s->cluster_bits, 1); |
| 1866 | s->free_byte_offset += size; |
| 1867 | } else { |
| 1868 | s->free_byte_offset = offset; |
| 1869 | goto redo; |
| 1870 | } |
| 1871 | } |
| 1872 | return offset; |
| 1873 | } |
| 1874 | |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1875 | static void free_clusters(BlockDriverState *bs, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1876 | int64_t offset, int64_t size) |
| 1877 | { |
| 1878 | update_refcount(bs, offset, size, -1); |
| 1879 | } |
| 1880 | |
| 1881 | static int grow_refcount_table(BlockDriverState *bs, int min_size) |
| 1882 | { |
| 1883 | BDRVQcowState *s = bs->opaque; |
| 1884 | int new_table_size, new_table_size2, refcount_table_clusters, i, ret; |
| 1885 | uint64_t *new_table; |
| 1886 | int64_t table_offset; |
| 1887 | uint64_t data64; |
| 1888 | uint32_t data32; |
ths | 23be50f | 2007-04-02 12:48:47 +0000 | [diff] [blame] | 1889 | int old_table_size; |
| 1890 | int64_t old_table_offset; |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1891 | |
| 1892 | if (min_size <= s->refcount_table_size) |
| 1893 | return 0; |
| 1894 | /* compute new table size */ |
| 1895 | refcount_table_clusters = s->refcount_table_size >> (s->cluster_bits - 3); |
| 1896 | for(;;) { |
| 1897 | if (refcount_table_clusters == 0) { |
| 1898 | refcount_table_clusters = 1; |
| 1899 | } else { |
| 1900 | refcount_table_clusters = (refcount_table_clusters * 3 + 1) / 2; |
| 1901 | } |
| 1902 | new_table_size = refcount_table_clusters << (s->cluster_bits - 3); |
| 1903 | if (min_size <= new_table_size) |
| 1904 | break; |
| 1905 | } |
bellard | 15e6690 | 2006-08-05 22:24:28 +0000 | [diff] [blame] | 1906 | #ifdef DEBUG_ALLOC2 |
| 1907 | printf("grow_refcount_table from %d to %d\n", |
| 1908 | s->refcount_table_size, |
| 1909 | new_table_size); |
| 1910 | #endif |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1911 | new_table_size2 = new_table_size * sizeof(uint64_t); |
| 1912 | new_table = qemu_mallocz(new_table_size2); |
| 1913 | if (!new_table) |
| 1914 | return -ENOMEM; |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1915 | memcpy(new_table, s->refcount_table, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1916 | s->refcount_table_size * sizeof(uint64_t)); |
| 1917 | for(i = 0; i < s->refcount_table_size; i++) |
| 1918 | cpu_to_be64s(&new_table[i]); |
| 1919 | /* Note: we cannot update the refcount now to avoid recursion */ |
| 1920 | table_offset = alloc_clusters_noref(bs, new_table_size2); |
| 1921 | ret = bdrv_pwrite(s->hd, table_offset, new_table, new_table_size2); |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1922 | if (ret != new_table_size2) |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1923 | goto fail; |
| 1924 | for(i = 0; i < s->refcount_table_size; i++) |
| 1925 | be64_to_cpus(&new_table[i]); |
| 1926 | |
| 1927 | data64 = cpu_to_be64(table_offset); |
| 1928 | if (bdrv_pwrite(s->hd, offsetof(QCowHeader, refcount_table_offset), |
| 1929 | &data64, sizeof(data64)) != sizeof(data64)) |
| 1930 | goto fail; |
| 1931 | data32 = cpu_to_be32(refcount_table_clusters); |
| 1932 | if (bdrv_pwrite(s->hd, offsetof(QCowHeader, refcount_table_clusters), |
| 1933 | &data32, sizeof(data32)) != sizeof(data32)) |
| 1934 | goto fail; |
| 1935 | qemu_free(s->refcount_table); |
ths | 23be50f | 2007-04-02 12:48:47 +0000 | [diff] [blame] | 1936 | old_table_offset = s->refcount_table_offset; |
| 1937 | old_table_size = s->refcount_table_size; |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1938 | s->refcount_table = new_table; |
| 1939 | s->refcount_table_size = new_table_size; |
ths | a4080ec | 2007-04-01 19:01:40 +0000 | [diff] [blame] | 1940 | s->refcount_table_offset = table_offset; |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1941 | |
| 1942 | update_refcount(bs, table_offset, new_table_size2, 1); |
ths | 23be50f | 2007-04-02 12:48:47 +0000 | [diff] [blame] | 1943 | free_clusters(bs, old_table_offset, old_table_size * sizeof(uint64_t)); |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1944 | return 0; |
| 1945 | fail: |
| 1946 | free_clusters(bs, table_offset, new_table_size2); |
| 1947 | qemu_free(new_table); |
| 1948 | return -EIO; |
| 1949 | } |
| 1950 | |
| 1951 | /* addend must be 1 or -1 */ |
| 1952 | /* XXX: cache several refcount block clusters ? */ |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1953 | static int update_cluster_refcount(BlockDriverState *bs, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1954 | int64_t cluster_index, |
| 1955 | int addend) |
| 1956 | { |
| 1957 | BDRVQcowState *s = bs->opaque; |
| 1958 | int64_t offset, refcount_block_offset; |
| 1959 | int ret, refcount_table_index, block_index, refcount; |
| 1960 | uint64_t data64; |
| 1961 | |
| 1962 | refcount_table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT); |
| 1963 | if (refcount_table_index >= s->refcount_table_size) { |
| 1964 | if (addend < 0) |
| 1965 | return -EINVAL; |
| 1966 | ret = grow_refcount_table(bs, refcount_table_index + 1); |
| 1967 | if (ret < 0) |
| 1968 | return ret; |
| 1969 | } |
| 1970 | refcount_block_offset = s->refcount_table[refcount_table_index]; |
| 1971 | if (!refcount_block_offset) { |
| 1972 | if (addend < 0) |
| 1973 | return -EINVAL; |
| 1974 | /* create a new refcount block */ |
| 1975 | /* Note: we cannot update the refcount now to avoid recursion */ |
| 1976 | offset = alloc_clusters_noref(bs, s->cluster_size); |
| 1977 | memset(s->refcount_block_cache, 0, s->cluster_size); |
| 1978 | ret = bdrv_pwrite(s->hd, offset, s->refcount_block_cache, s->cluster_size); |
| 1979 | if (ret != s->cluster_size) |
| 1980 | return -EINVAL; |
| 1981 | s->refcount_table[refcount_table_index] = offset; |
| 1982 | data64 = cpu_to_be64(offset); |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1983 | ret = bdrv_pwrite(s->hd, s->refcount_table_offset + |
| 1984 | refcount_table_index * sizeof(uint64_t), |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 1985 | &data64, sizeof(data64)); |
| 1986 | if (ret != sizeof(data64)) |
| 1987 | return -EINVAL; |
| 1988 | |
| 1989 | refcount_block_offset = offset; |
| 1990 | s->refcount_block_cache_offset = offset; |
| 1991 | update_refcount(bs, offset, s->cluster_size, 1); |
| 1992 | } else { |
| 1993 | if (refcount_block_offset != s->refcount_block_cache_offset) { |
| 1994 | if (load_refcount_block(bs, refcount_block_offset) < 0) |
| 1995 | return -EIO; |
| 1996 | } |
| 1997 | } |
| 1998 | /* we can update the count and save it */ |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 1999 | block_index = cluster_index & |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 2000 | ((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1); |
| 2001 | refcount = be16_to_cpu(s->refcount_block_cache[block_index]); |
| 2002 | refcount += addend; |
| 2003 | if (refcount < 0 || refcount > 0xffff) |
| 2004 | return -EINVAL; |
| 2005 | if (refcount == 0 && cluster_index < s->free_cluster_index) { |
| 2006 | s->free_cluster_index = cluster_index; |
| 2007 | } |
| 2008 | s->refcount_block_cache[block_index] = cpu_to_be16(refcount); |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 2009 | if (bdrv_pwrite(s->hd, |
| 2010 | refcount_block_offset + (block_index << REFCOUNT_SHIFT), |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 2011 | &s->refcount_block_cache[block_index], 2) != 2) |
| 2012 | return -EIO; |
| 2013 | return refcount; |
| 2014 | } |
| 2015 | |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 2016 | static void update_refcount(BlockDriverState *bs, |
| 2017 | int64_t offset, int64_t length, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 2018 | int addend) |
| 2019 | { |
| 2020 | BDRVQcowState *s = bs->opaque; |
| 2021 | int64_t start, last, cluster_offset; |
| 2022 | |
| 2023 | #ifdef DEBUG_ALLOC2 |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 2024 | printf("update_refcount: offset=%lld size=%lld addend=%d\n", |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 2025 | offset, length, addend); |
| 2026 | #endif |
| 2027 | if (length <= 0) |
| 2028 | return; |
| 2029 | start = offset & ~(s->cluster_size - 1); |
| 2030 | last = (offset + length - 1) & ~(s->cluster_size - 1); |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 2031 | for(cluster_offset = start; cluster_offset <= last; |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 2032 | cluster_offset += s->cluster_size) { |
| 2033 | update_cluster_refcount(bs, cluster_offset >> s->cluster_bits, addend); |
| 2034 | } |
| 2035 | } |
| 2036 | |
| 2037 | #ifdef DEBUG_ALLOC |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 2038 | static void inc_refcounts(BlockDriverState *bs, |
| 2039 | uint16_t *refcount_table, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 2040 | int refcount_table_size, |
| 2041 | int64_t offset, int64_t size) |
| 2042 | { |
| 2043 | BDRVQcowState *s = bs->opaque; |
| 2044 | int64_t start, last, cluster_offset; |
| 2045 | int k; |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 2046 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 2047 | if (size <= 0) |
| 2048 | return; |
| 2049 | |
| 2050 | start = offset & ~(s->cluster_size - 1); |
| 2051 | last = (offset + size - 1) & ~(s->cluster_size - 1); |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 2052 | for(cluster_offset = start; cluster_offset <= last; |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 2053 | cluster_offset += s->cluster_size) { |
| 2054 | k = cluster_offset >> s->cluster_bits; |
| 2055 | if (k < 0 || k >= refcount_table_size) { |
| 2056 | printf("ERROR: invalid cluster offset=0x%llx\n", cluster_offset); |
| 2057 | } else { |
| 2058 | if (++refcount_table[k] == 0) { |
| 2059 | printf("ERROR: overflow cluster offset=0x%llx\n", cluster_offset); |
| 2060 | } |
| 2061 | } |
| 2062 | } |
| 2063 | } |
| 2064 | |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 2065 | static int check_refcounts_l1(BlockDriverState *bs, |
| 2066 | uint16_t *refcount_table, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 2067 | int refcount_table_size, |
| 2068 | int64_t l1_table_offset, int l1_size, |
| 2069 | int check_copied) |
| 2070 | { |
| 2071 | BDRVQcowState *s = bs->opaque; |
| 2072 | uint64_t *l1_table, *l2_table, l2_offset, offset, l1_size2; |
| 2073 | int l2_size, i, j, nb_csectors, refcount; |
| 2074 | |
| 2075 | l2_table = NULL; |
| 2076 | l1_size2 = l1_size * sizeof(uint64_t); |
| 2077 | |
| 2078 | inc_refcounts(bs, refcount_table, refcount_table_size, |
| 2079 | l1_table_offset, l1_size2); |
| 2080 | |
| 2081 | l1_table = qemu_malloc(l1_size2); |
| 2082 | if (!l1_table) |
| 2083 | goto fail; |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 2084 | if (bdrv_pread(s->hd, l1_table_offset, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 2085 | l1_table, l1_size2) != l1_size2) |
| 2086 | goto fail; |
| 2087 | for(i = 0;i < l1_size; i++) |
| 2088 | be64_to_cpus(&l1_table[i]); |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 2089 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 2090 | l2_size = s->l2_size * sizeof(uint64_t); |
| 2091 | l2_table = qemu_malloc(l2_size); |
| 2092 | if (!l2_table) |
| 2093 | goto fail; |
| 2094 | for(i = 0; i < l1_size; i++) { |
| 2095 | l2_offset = l1_table[i]; |
| 2096 | if (l2_offset) { |
| 2097 | if (check_copied) { |
| 2098 | refcount = get_refcount(bs, (l2_offset & ~QCOW_OFLAG_COPIED) >> s->cluster_bits); |
| 2099 | if ((refcount == 1) != ((l2_offset & QCOW_OFLAG_COPIED) != 0)) { |
| 2100 | printf("ERROR OFLAG_COPIED: l2_offset=%llx refcount=%d\n", |
| 2101 | l2_offset, refcount); |
| 2102 | } |
| 2103 | } |
| 2104 | l2_offset &= ~QCOW_OFLAG_COPIED; |
| 2105 | if (bdrv_pread(s->hd, l2_offset, l2_table, l2_size) != l2_size) |
| 2106 | goto fail; |
| 2107 | for(j = 0; j < s->l2_size; j++) { |
| 2108 | offset = be64_to_cpu(l2_table[j]); |
| 2109 | if (offset != 0) { |
| 2110 | if (offset & QCOW_OFLAG_COMPRESSED) { |
| 2111 | if (offset & QCOW_OFLAG_COPIED) { |
| 2112 | printf("ERROR: cluster %lld: copied flag must never be set for compressed clusters\n", |
| 2113 | offset >> s->cluster_bits); |
| 2114 | offset &= ~QCOW_OFLAG_COPIED; |
| 2115 | } |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 2116 | nb_csectors = ((offset >> s->csize_shift) & |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 2117 | s->csize_mask) + 1; |
| 2118 | offset &= s->cluster_offset_mask; |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 2119 | inc_refcounts(bs, refcount_table, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 2120 | refcount_table_size, |
| 2121 | offset & ~511, nb_csectors * 512); |
| 2122 | } else { |
| 2123 | if (check_copied) { |
| 2124 | refcount = get_refcount(bs, (offset & ~QCOW_OFLAG_COPIED) >> s->cluster_bits); |
| 2125 | if ((refcount == 1) != ((offset & QCOW_OFLAG_COPIED) != 0)) { |
| 2126 | printf("ERROR OFLAG_COPIED: offset=%llx refcount=%d\n", |
| 2127 | offset, refcount); |
| 2128 | } |
| 2129 | } |
| 2130 | offset &= ~QCOW_OFLAG_COPIED; |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 2131 | inc_refcounts(bs, refcount_table, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 2132 | refcount_table_size, |
| 2133 | offset, s->cluster_size); |
| 2134 | } |
| 2135 | } |
| 2136 | } |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 2137 | inc_refcounts(bs, refcount_table, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 2138 | refcount_table_size, |
| 2139 | l2_offset, |
| 2140 | s->cluster_size); |
| 2141 | } |
| 2142 | } |
| 2143 | qemu_free(l1_table); |
| 2144 | qemu_free(l2_table); |
| 2145 | return 0; |
| 2146 | fail: |
| 2147 | printf("ERROR: I/O error in check_refcounts_l1\n"); |
| 2148 | qemu_free(l1_table); |
| 2149 | qemu_free(l2_table); |
| 2150 | return -EIO; |
| 2151 | } |
| 2152 | |
| 2153 | static void check_refcounts(BlockDriverState *bs) |
| 2154 | { |
| 2155 | BDRVQcowState *s = bs->opaque; |
| 2156 | int64_t size; |
| 2157 | int nb_clusters, refcount1, refcount2, i; |
| 2158 | QCowSnapshot *sn; |
| 2159 | uint16_t *refcount_table; |
| 2160 | |
| 2161 | size = bdrv_getlength(s->hd); |
| 2162 | nb_clusters = (size + s->cluster_size - 1) >> s->cluster_bits; |
| 2163 | refcount_table = qemu_mallocz(nb_clusters * sizeof(uint16_t)); |
bellard | 15e6690 | 2006-08-05 22:24:28 +0000 | [diff] [blame] | 2164 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 2165 | /* header */ |
| 2166 | inc_refcounts(bs, refcount_table, nb_clusters, |
| 2167 | 0, s->cluster_size); |
ths | 3b46e62 | 2007-09-17 08:09:54 +0000 | [diff] [blame] | 2168 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 2169 | check_refcounts_l1(bs, refcount_table, nb_clusters, |
| 2170 | s->l1_table_offset, s->l1_size, 1); |
| 2171 | |
| 2172 | /* snapshots */ |
| 2173 | for(i = 0; i < s->nb_snapshots; i++) { |
| 2174 | sn = s->snapshots + i; |
| 2175 | check_refcounts_l1(bs, refcount_table, nb_clusters, |
| 2176 | sn->l1_table_offset, sn->l1_size, 0); |
| 2177 | } |
| 2178 | inc_refcounts(bs, refcount_table, nb_clusters, |
| 2179 | s->snapshots_offset, s->snapshots_size); |
| 2180 | |
| 2181 | /* refcount data */ |
| 2182 | inc_refcounts(bs, refcount_table, nb_clusters, |
ths | 5fafdf2 | 2007-09-16 21:08:06 +0000 | [diff] [blame] | 2183 | s->refcount_table_offset, |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 2184 | s->refcount_table_size * sizeof(uint64_t)); |
| 2185 | for(i = 0; i < s->refcount_table_size; i++) { |
| 2186 | int64_t offset; |
| 2187 | offset = s->refcount_table[i]; |
| 2188 | if (offset != 0) { |
| 2189 | inc_refcounts(bs, refcount_table, nb_clusters, |
| 2190 | offset, s->cluster_size); |
| 2191 | } |
| 2192 | } |
| 2193 | |
| 2194 | /* compare ref counts */ |
| 2195 | for(i = 0; i < nb_clusters; i++) { |
| 2196 | refcount1 = get_refcount(bs, i); |
| 2197 | refcount2 = refcount_table[i]; |
| 2198 | if (refcount1 != refcount2) |
| 2199 | printf("ERROR cluster %d refcount=%d reference=%d\n", |
| 2200 | i, refcount1, refcount2); |
| 2201 | } |
| 2202 | |
| 2203 | qemu_free(refcount_table); |
| 2204 | } |
| 2205 | |
| 2206 | #if 0 |
| 2207 | static void dump_refcounts(BlockDriverState *bs) |
| 2208 | { |
| 2209 | BDRVQcowState *s = bs->opaque; |
| 2210 | int64_t nb_clusters, k, k1, size; |
| 2211 | int refcount; |
| 2212 | |
| 2213 | size = bdrv_getlength(s->hd); |
| 2214 | nb_clusters = (size + s->cluster_size - 1) >> s->cluster_bits; |
| 2215 | for(k = 0; k < nb_clusters;) { |
| 2216 | k1 = k; |
| 2217 | refcount = get_refcount(bs, k); |
| 2218 | k++; |
| 2219 | while (k < nb_clusters && get_refcount(bs, k) == refcount) |
| 2220 | k++; |
| 2221 | printf("%lld: refcount=%d nb=%lld\n", k, refcount, k - k1); |
| 2222 | } |
| 2223 | } |
| 2224 | #endif |
| 2225 | #endif |
| 2226 | |
| 2227 | BlockDriver bdrv_qcow2 = { |
| 2228 | "qcow2", |
| 2229 | sizeof(BDRVQcowState), |
| 2230 | qcow_probe, |
| 2231 | qcow_open, |
| 2232 | NULL, |
| 2233 | NULL, |
| 2234 | qcow_close, |
| 2235 | qcow_create, |
| 2236 | qcow_flush, |
| 2237 | qcow_is_allocated, |
| 2238 | qcow_set_key, |
| 2239 | qcow_make_empty, |
| 2240 | |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 2241 | .bdrv_aio_read = qcow_aio_read, |
| 2242 | .bdrv_aio_write = qcow_aio_write, |
| 2243 | .bdrv_aio_cancel = qcow_aio_cancel, |
pbrook | ce1a14d | 2006-08-07 02:38:06 +0000 | [diff] [blame] | 2244 | .aiocb_size = sizeof(QCowAIOCB), |
bellard | 585f858 | 2006-08-05 21:14:20 +0000 | [diff] [blame] | 2245 | .bdrv_write_compressed = qcow_write_compressed, |
| 2246 | |
| 2247 | .bdrv_snapshot_create = qcow_snapshot_create, |
| 2248 | .bdrv_snapshot_goto = qcow_snapshot_goto, |
| 2249 | .bdrv_snapshot_delete = qcow_snapshot_delete, |
| 2250 | .bdrv_snapshot_list = qcow_snapshot_list, |
| 2251 | .bdrv_get_info = qcow_get_info, |
| 2252 | }; |