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Commit | Line | Data |
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585f8587 FB |
1 | /* |
2 | * Block driver for the QCOW version 2 format | |
5fafdf24 | 3 | * |
585f8587 | 4 | * Copyright (c) 2004-2006 Fabrice Bellard |
5fafdf24 | 5 | * |
585f8587 FB |
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 | */ | |
faf07963 | 24 | #include "qemu-common.h" |
585f8587 FB |
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. | |
5fafdf24 | 37 | - Size of compressed clusters is stored in sectors to reduce bit usage |
585f8587 FB |
38 | in the cluster offsets. |
39 | - Support for storing additional data (such as the VM state) in the | |
3b46e624 | 40 | snapshots. |
585f8587 FB |
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 | |
5fafdf24 | 48 | |
585f8587 FB |
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 | ||
095a9c58 AL |
55 | #define QCOW_MAX_CRYPT_CLUSTERS 32 |
56 | ||
585f8587 FB |
57 | /* indicate that the refcount of the referenced cluster is exactly one. */ |
58 | #define QCOW_OFLAG_COPIED (1LL << 63) | |
59 | /* indicate that the cluster is compressed (they never have the copied flag) */ | |
60 | #define QCOW_OFLAG_COMPRESSED (1LL << 62) | |
61 | ||
62 | #define REFCOUNT_SHIFT 1 /* refcount size is 2 bytes */ | |
63 | ||
585f8587 FB |
64 | typedef struct QCowHeader { |
65 | uint32_t magic; | |
66 | uint32_t version; | |
67 | uint64_t backing_file_offset; | |
68 | uint32_t backing_file_size; | |
69 | uint32_t cluster_bits; | |
70 | uint64_t size; /* in bytes */ | |
71 | uint32_t crypt_method; | |
72 | uint32_t l1_size; /* XXX: save number of clusters instead ? */ | |
73 | uint64_t l1_table_offset; | |
74 | uint64_t refcount_table_offset; | |
75 | uint32_t refcount_table_clusters; | |
76 | uint32_t nb_snapshots; | |
77 | uint64_t snapshots_offset; | |
78 | } QCowHeader; | |
79 | ||
80 | typedef struct __attribute__((packed)) QCowSnapshotHeader { | |
81 | /* header is 8 byte aligned */ | |
82 | uint64_t l1_table_offset; | |
83 | ||
84 | uint32_t l1_size; | |
85 | uint16_t id_str_size; | |
86 | uint16_t name_size; | |
87 | ||
88 | uint32_t date_sec; | |
89 | uint32_t date_nsec; | |
90 | ||
91 | uint64_t vm_clock_nsec; | |
92 | ||
93 | uint32_t vm_state_size; | |
94 | uint32_t extra_data_size; /* for extension */ | |
95 | /* extra data follows */ | |
96 | /* id_str follows */ | |
97 | /* name follows */ | |
98 | } QCowSnapshotHeader; | |
99 | ||
100 | #define L2_CACHE_SIZE 16 | |
101 | ||
102 | typedef struct QCowSnapshot { | |
103 | uint64_t l1_table_offset; | |
104 | uint32_t l1_size; | |
105 | char *id_str; | |
106 | char *name; | |
107 | uint32_t vm_state_size; | |
108 | uint32_t date_sec; | |
109 | uint32_t date_nsec; | |
110 | uint64_t vm_clock_nsec; | |
111 | } QCowSnapshot; | |
112 | ||
113 | typedef struct BDRVQcowState { | |
114 | BlockDriverState *hd; | |
115 | int cluster_bits; | |
116 | int cluster_size; | |
117 | int cluster_sectors; | |
118 | int l2_bits; | |
119 | int l2_size; | |
120 | int l1_size; | |
121 | int l1_vm_state_index; | |
122 | int csize_shift; | |
123 | int csize_mask; | |
124 | uint64_t cluster_offset_mask; | |
125 | uint64_t l1_table_offset; | |
126 | uint64_t *l1_table; | |
127 | uint64_t *l2_cache; | |
128 | uint64_t l2_cache_offsets[L2_CACHE_SIZE]; | |
129 | uint32_t l2_cache_counts[L2_CACHE_SIZE]; | |
130 | uint8_t *cluster_cache; | |
131 | uint8_t *cluster_data; | |
132 | uint64_t cluster_cache_offset; | |
133 | ||
134 | uint64_t *refcount_table; | |
135 | uint64_t refcount_table_offset; | |
136 | uint32_t refcount_table_size; | |
137 | uint64_t refcount_block_cache_offset; | |
138 | uint16_t *refcount_block_cache; | |
139 | int64_t free_cluster_index; | |
140 | int64_t free_byte_offset; | |
141 | ||
142 | uint32_t crypt_method; /* current crypt method, 0 if no key yet */ | |
143 | uint32_t crypt_method_header; | |
144 | AES_KEY aes_encrypt_key; | |
145 | AES_KEY aes_decrypt_key; | |
146 | uint64_t snapshots_offset; | |
147 | int snapshots_size; | |
148 | int nb_snapshots; | |
149 | QCowSnapshot *snapshots; | |
150 | } BDRVQcowState; | |
151 | ||
152 | static int decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset); | |
5fafdf24 | 153 | static int qcow_read(BlockDriverState *bs, int64_t sector_num, |
585f8587 FB |
154 | uint8_t *buf, int nb_sectors); |
155 | static int qcow_read_snapshots(BlockDriverState *bs); | |
156 | static void qcow_free_snapshots(BlockDriverState *bs); | |
157 | static int refcount_init(BlockDriverState *bs); | |
158 | static void refcount_close(BlockDriverState *bs); | |
159 | static int get_refcount(BlockDriverState *bs, int64_t cluster_index); | |
5fafdf24 | 160 | static int update_cluster_refcount(BlockDriverState *bs, |
585f8587 FB |
161 | int64_t cluster_index, |
162 | int addend); | |
5fafdf24 TS |
163 | static void update_refcount(BlockDriverState *bs, |
164 | int64_t offset, int64_t length, | |
585f8587 FB |
165 | int addend); |
166 | static int64_t alloc_clusters(BlockDriverState *bs, int64_t size); | |
167 | static int64_t alloc_bytes(BlockDriverState *bs, int size); | |
5fafdf24 | 168 | static void free_clusters(BlockDriverState *bs, |
585f8587 FB |
169 | int64_t offset, int64_t size); |
170 | #ifdef DEBUG_ALLOC | |
171 | static void check_refcounts(BlockDriverState *bs); | |
172 | #endif | |
173 | ||
174 | static int qcow_probe(const uint8_t *buf, int buf_size, const char *filename) | |
175 | { | |
176 | const QCowHeader *cow_header = (const void *)buf; | |
3b46e624 | 177 | |
585f8587 FB |
178 | if (buf_size >= sizeof(QCowHeader) && |
179 | be32_to_cpu(cow_header->magic) == QCOW_MAGIC && | |
5fafdf24 | 180 | be32_to_cpu(cow_header->version) == QCOW_VERSION) |
585f8587 FB |
181 | return 100; |
182 | else | |
183 | return 0; | |
184 | } | |
185 | ||
186 | static int qcow_open(BlockDriverState *bs, const char *filename, int flags) | |
187 | { | |
188 | BDRVQcowState *s = bs->opaque; | |
189 | int len, i, shift, ret; | |
190 | QCowHeader header; | |
191 | ||
b5eff355 | 192 | ret = bdrv_file_open(&s->hd, filename, flags); |
585f8587 FB |
193 | if (ret < 0) |
194 | return ret; | |
195 | if (bdrv_pread(s->hd, 0, &header, sizeof(header)) != sizeof(header)) | |
196 | goto fail; | |
197 | be32_to_cpus(&header.magic); | |
198 | be32_to_cpus(&header.version); | |
199 | be64_to_cpus(&header.backing_file_offset); | |
200 | be32_to_cpus(&header.backing_file_size); | |
201 | be64_to_cpus(&header.size); | |
202 | be32_to_cpus(&header.cluster_bits); | |
203 | be32_to_cpus(&header.crypt_method); | |
204 | be64_to_cpus(&header.l1_table_offset); | |
205 | be32_to_cpus(&header.l1_size); | |
206 | be64_to_cpus(&header.refcount_table_offset); | |
207 | be32_to_cpus(&header.refcount_table_clusters); | |
208 | be64_to_cpus(&header.snapshots_offset); | |
209 | be32_to_cpus(&header.nb_snapshots); | |
3b46e624 | 210 | |
585f8587 FB |
211 | if (header.magic != QCOW_MAGIC || header.version != QCOW_VERSION) |
212 | goto fail; | |
5fafdf24 TS |
213 | if (header.size <= 1 || |
214 | header.cluster_bits < 9 || | |
585f8587 FB |
215 | header.cluster_bits > 16) |
216 | goto fail; | |
217 | if (header.crypt_method > QCOW_CRYPT_AES) | |
218 | goto fail; | |
219 | s->crypt_method_header = header.crypt_method; | |
220 | if (s->crypt_method_header) | |
221 | bs->encrypted = 1; | |
222 | s->cluster_bits = header.cluster_bits; | |
223 | s->cluster_size = 1 << s->cluster_bits; | |
224 | s->cluster_sectors = 1 << (s->cluster_bits - 9); | |
225 | s->l2_bits = s->cluster_bits - 3; /* L2 is always one cluster */ | |
226 | s->l2_size = 1 << s->l2_bits; | |
227 | bs->total_sectors = header.size / 512; | |
228 | s->csize_shift = (62 - (s->cluster_bits - 8)); | |
229 | s->csize_mask = (1 << (s->cluster_bits - 8)) - 1; | |
230 | s->cluster_offset_mask = (1LL << s->csize_shift) - 1; | |
231 | s->refcount_table_offset = header.refcount_table_offset; | |
5fafdf24 | 232 | s->refcount_table_size = |
585f8587 FB |
233 | header.refcount_table_clusters << (s->cluster_bits - 3); |
234 | ||
235 | s->snapshots_offset = header.snapshots_offset; | |
236 | s->nb_snapshots = header.nb_snapshots; | |
237 | ||
238 | /* read the level 1 table */ | |
239 | s->l1_size = header.l1_size; | |
240 | shift = s->cluster_bits + s->l2_bits; | |
241 | s->l1_vm_state_index = (header.size + (1LL << shift) - 1) >> shift; | |
242 | /* the L1 table must contain at least enough entries to put | |
243 | header.size bytes */ | |
244 | if (s->l1_size < s->l1_vm_state_index) | |
245 | goto fail; | |
246 | s->l1_table_offset = header.l1_table_offset; | |
247 | s->l1_table = qemu_malloc(s->l1_size * sizeof(uint64_t)); | |
248 | if (!s->l1_table) | |
249 | goto fail; | |
5fafdf24 | 250 | if (bdrv_pread(s->hd, s->l1_table_offset, s->l1_table, s->l1_size * sizeof(uint64_t)) != |
585f8587 FB |
251 | s->l1_size * sizeof(uint64_t)) |
252 | goto fail; | |
253 | for(i = 0;i < s->l1_size; i++) { | |
254 | be64_to_cpus(&s->l1_table[i]); | |
255 | } | |
256 | /* alloc L2 cache */ | |
257 | s->l2_cache = qemu_malloc(s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t)); | |
258 | if (!s->l2_cache) | |
259 | goto fail; | |
260 | s->cluster_cache = qemu_malloc(s->cluster_size); | |
261 | if (!s->cluster_cache) | |
262 | goto fail; | |
263 | /* one more sector for decompressed data alignment */ | |
095a9c58 AL |
264 | s->cluster_data = qemu_malloc(QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size |
265 | + 512); | |
585f8587 FB |
266 | if (!s->cluster_data) |
267 | goto fail; | |
268 | s->cluster_cache_offset = -1; | |
3b46e624 | 269 | |
585f8587 FB |
270 | if (refcount_init(bs) < 0) |
271 | goto fail; | |
272 | ||
273 | /* read the backing file name */ | |
274 | if (header.backing_file_offset != 0) { | |
275 | len = header.backing_file_size; | |
276 | if (len > 1023) | |
277 | len = 1023; | |
278 | if (bdrv_pread(s->hd, header.backing_file_offset, bs->backing_file, len) != len) | |
279 | goto fail; | |
280 | bs->backing_file[len] = '\0'; | |
281 | } | |
282 | if (qcow_read_snapshots(bs) < 0) | |
283 | goto fail; | |
284 | ||
285 | #ifdef DEBUG_ALLOC | |
286 | check_refcounts(bs); | |
287 | #endif | |
288 | return 0; | |
289 | ||
290 | fail: | |
291 | qcow_free_snapshots(bs); | |
292 | refcount_close(bs); | |
293 | qemu_free(s->l1_table); | |
294 | qemu_free(s->l2_cache); | |
295 | qemu_free(s->cluster_cache); | |
296 | qemu_free(s->cluster_data); | |
297 | bdrv_delete(s->hd); | |
298 | return -1; | |
299 | } | |
300 | ||
301 | static int qcow_set_key(BlockDriverState *bs, const char *key) | |
302 | { | |
303 | BDRVQcowState *s = bs->opaque; | |
304 | uint8_t keybuf[16]; | |
305 | int len, i; | |
3b46e624 | 306 | |
585f8587 FB |
307 | memset(keybuf, 0, 16); |
308 | len = strlen(key); | |
309 | if (len > 16) | |
310 | len = 16; | |
311 | /* XXX: we could compress the chars to 7 bits to increase | |
312 | entropy */ | |
313 | for(i = 0;i < len;i++) { | |
314 | keybuf[i] = key[i]; | |
315 | } | |
316 | s->crypt_method = s->crypt_method_header; | |
317 | ||
318 | if (AES_set_encrypt_key(keybuf, 128, &s->aes_encrypt_key) != 0) | |
319 | return -1; | |
320 | if (AES_set_decrypt_key(keybuf, 128, &s->aes_decrypt_key) != 0) | |
321 | return -1; | |
322 | #if 0 | |
323 | /* test */ | |
324 | { | |
325 | uint8_t in[16]; | |
326 | uint8_t out[16]; | |
327 | uint8_t tmp[16]; | |
328 | for(i=0;i<16;i++) | |
329 | in[i] = i; | |
330 | AES_encrypt(in, tmp, &s->aes_encrypt_key); | |
331 | AES_decrypt(tmp, out, &s->aes_decrypt_key); | |
332 | for(i = 0; i < 16; i++) | |
333 | printf(" %02x", tmp[i]); | |
334 | printf("\n"); | |
335 | for(i = 0; i < 16; i++) | |
336 | printf(" %02x", out[i]); | |
337 | printf("\n"); | |
338 | } | |
339 | #endif | |
340 | return 0; | |
341 | } | |
342 | ||
343 | /* The crypt function is compatible with the linux cryptoloop | |
344 | algorithm for < 4 GB images. NOTE: out_buf == in_buf is | |
345 | supported */ | |
346 | static void encrypt_sectors(BDRVQcowState *s, int64_t sector_num, | |
347 | uint8_t *out_buf, const uint8_t *in_buf, | |
348 | int nb_sectors, int enc, | |
349 | const AES_KEY *key) | |
350 | { | |
351 | union { | |
352 | uint64_t ll[2]; | |
353 | uint8_t b[16]; | |
354 | } ivec; | |
355 | int i; | |
356 | ||
357 | for(i = 0; i < nb_sectors; i++) { | |
358 | ivec.ll[0] = cpu_to_le64(sector_num); | |
359 | ivec.ll[1] = 0; | |
5fafdf24 | 360 | AES_cbc_encrypt(in_buf, out_buf, 512, key, |
585f8587 FB |
361 | ivec.b, enc); |
362 | sector_num++; | |
363 | in_buf += 512; | |
364 | out_buf += 512; | |
365 | } | |
366 | } | |
367 | ||
368 | static int copy_sectors(BlockDriverState *bs, uint64_t start_sect, | |
369 | uint64_t cluster_offset, int n_start, int n_end) | |
370 | { | |
371 | BDRVQcowState *s = bs->opaque; | |
372 | int n, ret; | |
373 | ||
374 | n = n_end - n_start; | |
375 | if (n <= 0) | |
376 | return 0; | |
377 | ret = qcow_read(bs, start_sect + n_start, s->cluster_data, n); | |
378 | if (ret < 0) | |
379 | return ret; | |
380 | if (s->crypt_method) { | |
5fafdf24 TS |
381 | encrypt_sectors(s, start_sect + n_start, |
382 | s->cluster_data, | |
585f8587 FB |
383 | s->cluster_data, n, 1, |
384 | &s->aes_encrypt_key); | |
385 | } | |
5fafdf24 | 386 | ret = bdrv_write(s->hd, (cluster_offset >> 9) + n_start, |
585f8587 FB |
387 | s->cluster_data, n); |
388 | if (ret < 0) | |
389 | return ret; | |
390 | return 0; | |
391 | } | |
392 | ||
393 | static void l2_cache_reset(BlockDriverState *bs) | |
394 | { | |
395 | BDRVQcowState *s = bs->opaque; | |
396 | ||
397 | memset(s->l2_cache, 0, s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t)); | |
398 | memset(s->l2_cache_offsets, 0, L2_CACHE_SIZE * sizeof(uint64_t)); | |
399 | memset(s->l2_cache_counts, 0, L2_CACHE_SIZE * sizeof(uint32_t)); | |
400 | } | |
401 | ||
402 | static inline int l2_cache_new_entry(BlockDriverState *bs) | |
403 | { | |
404 | BDRVQcowState *s = bs->opaque; | |
405 | uint32_t min_count; | |
406 | int min_index, i; | |
407 | ||
408 | /* find a new entry in the least used one */ | |
409 | min_index = 0; | |
410 | min_count = 0xffffffff; | |
411 | for(i = 0; i < L2_CACHE_SIZE; i++) { | |
412 | if (s->l2_cache_counts[i] < min_count) { | |
413 | min_count = s->l2_cache_counts[i]; | |
414 | min_index = i; | |
415 | } | |
416 | } | |
417 | return min_index; | |
418 | } | |
419 | ||
420 | static int64_t align_offset(int64_t offset, int n) | |
421 | { | |
422 | offset = (offset + n - 1) & ~(n - 1); | |
423 | return offset; | |
424 | } | |
425 | ||
426 | static int grow_l1_table(BlockDriverState *bs, int min_size) | |
427 | { | |
428 | BDRVQcowState *s = bs->opaque; | |
429 | int new_l1_size, new_l1_size2, ret, i; | |
430 | uint64_t *new_l1_table; | |
431 | uint64_t new_l1_table_offset; | |
432 | uint64_t data64; | |
433 | uint32_t data32; | |
434 | ||
435 | new_l1_size = s->l1_size; | |
436 | if (min_size <= new_l1_size) | |
437 | return 0; | |
438 | while (min_size > new_l1_size) { | |
439 | new_l1_size = (new_l1_size * 3 + 1) / 2; | |
440 | } | |
441 | #ifdef DEBUG_ALLOC2 | |
442 | printf("grow l1_table from %d to %d\n", s->l1_size, new_l1_size); | |
443 | #endif | |
444 | ||
445 | new_l1_size2 = sizeof(uint64_t) * new_l1_size; | |
446 | new_l1_table = qemu_mallocz(new_l1_size2); | |
447 | if (!new_l1_table) | |
448 | return -ENOMEM; | |
449 | memcpy(new_l1_table, s->l1_table, s->l1_size * sizeof(uint64_t)); | |
450 | ||
451 | /* write new table (align to cluster) */ | |
452 | new_l1_table_offset = alloc_clusters(bs, new_l1_size2); | |
3b46e624 | 453 | |
585f8587 FB |
454 | for(i = 0; i < s->l1_size; i++) |
455 | new_l1_table[i] = cpu_to_be64(new_l1_table[i]); | |
456 | ret = bdrv_pwrite(s->hd, new_l1_table_offset, new_l1_table, new_l1_size2); | |
457 | if (ret != new_l1_size2) | |
458 | goto fail; | |
459 | for(i = 0; i < s->l1_size; i++) | |
460 | new_l1_table[i] = be64_to_cpu(new_l1_table[i]); | |
3b46e624 | 461 | |
585f8587 FB |
462 | /* set new table */ |
463 | data64 = cpu_to_be64(new_l1_table_offset); | |
464 | if (bdrv_pwrite(s->hd, offsetof(QCowHeader, l1_table_offset), | |
465 | &data64, sizeof(data64)) != sizeof(data64)) | |
466 | goto fail; | |
467 | data32 = cpu_to_be32(new_l1_size); | |
468 | if (bdrv_pwrite(s->hd, offsetof(QCowHeader, l1_size), | |
469 | &data32, sizeof(data32)) != sizeof(data32)) | |
470 | goto fail; | |
471 | qemu_free(s->l1_table); | |
472 | free_clusters(bs, s->l1_table_offset, s->l1_size * sizeof(uint64_t)); | |
473 | s->l1_table_offset = new_l1_table_offset; | |
474 | s->l1_table = new_l1_table; | |
475 | s->l1_size = new_l1_size; | |
476 | return 0; | |
477 | fail: | |
478 | qemu_free(s->l1_table); | |
479 | return -EIO; | |
480 | } | |
481 | ||
108534b9 AL |
482 | /* |
483 | * seek_l2_table | |
585f8587 | 484 | * |
108534b9 AL |
485 | * seek l2_offset in the l2_cache table |
486 | * if not found, return NULL, | |
487 | * if found, | |
488 | * increments the l2 cache hit count of the entry, | |
489 | * if counter overflow, divide by two all counters | |
490 | * return the pointer to the l2 cache entry | |
585f8587 | 491 | * |
108534b9 AL |
492 | */ |
493 | ||
494 | static uint64_t *seek_l2_table(BDRVQcowState *s, uint64_t l2_offset) | |
495 | { | |
496 | int i, j; | |
497 | ||
498 | for(i = 0; i < L2_CACHE_SIZE; i++) { | |
499 | if (l2_offset == s->l2_cache_offsets[i]) { | |
500 | /* increment the hit count */ | |
501 | if (++s->l2_cache_counts[i] == 0xffffffff) { | |
502 | for(j = 0; j < L2_CACHE_SIZE; j++) { | |
503 | s->l2_cache_counts[j] >>= 1; | |
504 | } | |
505 | } | |
506 | return s->l2_cache + (i << s->l2_bits); | |
507 | } | |
508 | } | |
509 | return NULL; | |
510 | } | |
511 | ||
512 | /* | |
513 | * l2_load | |
514 | * | |
515 | * Loads a L2 table into memory. If the table is in the cache, the cache | |
516 | * is used; otherwise the L2 table is loaded from the image file. | |
517 | * | |
518 | * Returns a pointer to the L2 table on success, or NULL if the read from | |
519 | * the image file failed. | |
520 | */ | |
521 | ||
522 | static uint64_t *l2_load(BlockDriverState *bs, uint64_t l2_offset) | |
523 | { | |
524 | BDRVQcowState *s = bs->opaque; | |
525 | int min_index; | |
526 | uint64_t *l2_table; | |
527 | ||
528 | /* seek if the table for the given offset is in the cache */ | |
529 | ||
530 | l2_table = seek_l2_table(s, l2_offset); | |
531 | if (l2_table != NULL) | |
532 | return l2_table; | |
533 | ||
534 | /* not found: load a new entry in the least used one */ | |
535 | ||
536 | min_index = l2_cache_new_entry(bs); | |
537 | l2_table = s->l2_cache + (min_index << s->l2_bits); | |
538 | if (bdrv_pread(s->hd, l2_offset, l2_table, s->l2_size * sizeof(uint64_t)) != | |
539 | s->l2_size * sizeof(uint64_t)) | |
540 | return NULL; | |
541 | s->l2_cache_offsets[min_index] = l2_offset; | |
542 | s->l2_cache_counts[min_index] = 1; | |
543 | ||
544 | return l2_table; | |
545 | } | |
546 | ||
547 | /* | |
548 | * l2_allocate | |
585f8587 | 549 | * |
108534b9 AL |
550 | * Allocate a new l2 entry in the file. If l1_index points to an already |
551 | * used entry in the L2 table (i.e. we are doing a copy on write for the L2 | |
552 | * table) copy the contents of the old L2 table into the newly allocated one. | |
553 | * Otherwise the new table is initialized with zeros. | |
585f8587 | 554 | * |
585f8587 | 555 | */ |
108534b9 AL |
556 | |
557 | static uint64_t *l2_allocate(BlockDriverState *bs, int l1_index) | |
558 | { | |
559 | BDRVQcowState *s = bs->opaque; | |
560 | int min_index; | |
561 | uint64_t old_l2_offset, tmp; | |
562 | uint64_t *l2_table, l2_offset; | |
563 | ||
564 | old_l2_offset = s->l1_table[l1_index]; | |
565 | ||
566 | /* allocate a new l2 entry */ | |
567 | ||
568 | l2_offset = alloc_clusters(bs, s->l2_size * sizeof(uint64_t)); | |
569 | ||
570 | /* update the L1 entry */ | |
571 | ||
572 | s->l1_table[l1_index] = l2_offset | QCOW_OFLAG_COPIED; | |
573 | ||
574 | tmp = cpu_to_be64(l2_offset | QCOW_OFLAG_COPIED); | |
575 | if (bdrv_pwrite(s->hd, s->l1_table_offset + l1_index * sizeof(tmp), | |
576 | &tmp, sizeof(tmp)) != sizeof(tmp)) | |
577 | return NULL; | |
578 | ||
579 | /* allocate a new entry in the l2 cache */ | |
580 | ||
581 | min_index = l2_cache_new_entry(bs); | |
582 | l2_table = s->l2_cache + (min_index << s->l2_bits); | |
583 | ||
584 | if (old_l2_offset == 0) { | |
585 | /* if there was no old l2 table, clear the new table */ | |
586 | memset(l2_table, 0, s->l2_size * sizeof(uint64_t)); | |
587 | } else { | |
588 | /* if there was an old l2 table, read it from the disk */ | |
589 | if (bdrv_pread(s->hd, old_l2_offset, | |
590 | l2_table, s->l2_size * sizeof(uint64_t)) != | |
591 | s->l2_size * sizeof(uint64_t)) | |
592 | return NULL; | |
593 | } | |
594 | /* write the l2 table to the file */ | |
595 | if (bdrv_pwrite(s->hd, l2_offset, | |
596 | l2_table, s->l2_size * sizeof(uint64_t)) != | |
597 | s->l2_size * sizeof(uint64_t)) | |
598 | return NULL; | |
599 | ||
600 | /* update the l2 cache entry */ | |
601 | ||
602 | s->l2_cache_offsets[min_index] = l2_offset; | |
603 | s->l2_cache_counts[min_index] = 1; | |
604 | ||
605 | return l2_table; | |
606 | } | |
607 | ||
05203524 AL |
608 | /* |
609 | * get_cluster_offset | |
610 | * | |
611 | * For a given offset of the disk image, return cluster offset in | |
612 | * qcow2 file. | |
613 | * | |
095a9c58 AL |
614 | * on entry, *num is the number of contiguous clusters we'd like to |
615 | * access following offset. | |
616 | * | |
617 | * on exit, *num is the number of contiguous clusters we can read. | |
618 | * | |
05203524 AL |
619 | * Return 1, if the offset is found |
620 | * Return 0, otherwise. | |
621 | * | |
622 | */ | |
623 | ||
095a9c58 AL |
624 | static uint64_t get_cluster_offset(BlockDriverState *bs, |
625 | uint64_t offset, int *num) | |
05203524 AL |
626 | { |
627 | BDRVQcowState *s = bs->opaque; | |
628 | int l1_index, l2_index; | |
095a9c58 AL |
629 | uint64_t l2_offset, *l2_table, cluster_offset, next; |
630 | int l1_bits; | |
631 | int index_in_cluster, nb_available, nb_needed; | |
632 | ||
633 | index_in_cluster = (offset >> 9) & (s->cluster_sectors - 1); | |
634 | nb_needed = *num + index_in_cluster; | |
635 | ||
636 | l1_bits = s->l2_bits + s->cluster_bits; | |
637 | ||
638 | /* compute how many bytes there are between the offset and | |
639 | * and the end of the l1 entry | |
640 | */ | |
641 | ||
642 | nb_available = (1 << l1_bits) - (offset & ((1 << l1_bits) - 1)); | |
643 | ||
644 | /* compute the number of available sectors */ | |
645 | ||
646 | nb_available = (nb_available >> 9) + index_in_cluster; | |
647 | ||
648 | cluster_offset = 0; | |
05203524 AL |
649 | |
650 | /* seek the the l2 offset in the l1 table */ | |
651 | ||
095a9c58 | 652 | l1_index = offset >> l1_bits; |
05203524 | 653 | if (l1_index >= s->l1_size) |
095a9c58 | 654 | goto out; |
05203524 AL |
655 | |
656 | l2_offset = s->l1_table[l1_index]; | |
657 | ||
658 | /* seek the l2 table of the given l2 offset */ | |
659 | ||
660 | if (!l2_offset) | |
095a9c58 | 661 | goto out; |
05203524 AL |
662 | |
663 | /* load the l2 table in memory */ | |
664 | ||
665 | l2_offset &= ~QCOW_OFLAG_COPIED; | |
666 | l2_table = l2_load(bs, l2_offset); | |
667 | if (l2_table == NULL) | |
768706a5 | 668 | return 0; |
05203524 AL |
669 | |
670 | /* find the cluster offset for the given disk offset */ | |
671 | ||
672 | l2_index = (offset >> s->cluster_bits) & (s->l2_size - 1); | |
673 | cluster_offset = be64_to_cpu(l2_table[l2_index]); | |
095a9c58 AL |
674 | nb_available = s->cluster_sectors; |
675 | l2_index++; | |
676 | ||
677 | if (!cluster_offset) { | |
05203524 | 678 | |
095a9c58 AL |
679 | /* how many empty clusters ? */ |
680 | ||
681 | while (nb_available < nb_needed && !l2_table[l2_index]) { | |
682 | l2_index++; | |
683 | nb_available += s->cluster_sectors; | |
684 | } | |
685 | } else { | |
686 | ||
687 | /* how many allocated clusters ? */ | |
688 | ||
689 | cluster_offset &= ~QCOW_OFLAG_COPIED; | |
690 | while (nb_available < nb_needed) { | |
691 | next = be64_to_cpu(l2_table[l2_index]) & ~QCOW_OFLAG_COPIED; | |
692 | if (next != cluster_offset + (nb_available << 9)) | |
693 | break; | |
694 | l2_index++; | |
695 | nb_available += s->cluster_sectors; | |
696 | } | |
697 | } | |
698 | ||
699 | out: | |
700 | if (nb_available > nb_needed) | |
701 | nb_available = nb_needed; | |
702 | ||
703 | *num = nb_available - index_in_cluster; | |
704 | ||
705 | return cluster_offset; | |
05203524 AL |
706 | } |
707 | ||
708 | /* | |
52d893ec | 709 | * free_any_clusters |
05203524 | 710 | * |
52d893ec | 711 | * free clusters according to its type: compressed or not |
05203524 | 712 | * |
52d893ec AL |
713 | */ |
714 | ||
715 | static void free_any_clusters(BlockDriverState *bs, | |
095a9c58 | 716 | uint64_t cluster_offset, int nb_clusters) |
52d893ec AL |
717 | { |
718 | BDRVQcowState *s = bs->opaque; | |
719 | ||
52d893ec AL |
720 | /* free the cluster */ |
721 | ||
722 | if (cluster_offset & QCOW_OFLAG_COMPRESSED) { | |
723 | int nb_csectors; | |
724 | nb_csectors = ((cluster_offset >> s->csize_shift) & | |
725 | s->csize_mask) + 1; | |
726 | free_clusters(bs, (cluster_offset & s->cluster_offset_mask) & ~511, | |
727 | nb_csectors * 512); | |
728 | return; | |
729 | } | |
730 | ||
095a9c58 AL |
731 | free_clusters(bs, cluster_offset, nb_clusters << s->cluster_bits); |
732 | ||
733 | return; | |
52d893ec AL |
734 | } |
735 | ||
736 | /* | |
737 | * get_cluster_table | |
05203524 | 738 | * |
52d893ec AL |
739 | * for a given disk offset, load (and allocate if needed) |
740 | * the l2 table. | |
741 | * | |
742 | * the l2 table offset in the qcow2 file and the cluster index | |
743 | * in the l2 table are given to the caller. | |
05203524 AL |
744 | * |
745 | */ | |
746 | ||
52d893ec AL |
747 | static int get_cluster_table(BlockDriverState *bs, uint64_t offset, |
748 | uint64_t **new_l2_table, | |
749 | uint64_t *new_l2_offset, | |
750 | int *new_l2_index) | |
585f8587 FB |
751 | { |
752 | BDRVQcowState *s = bs->opaque; | |
108534b9 | 753 | int l1_index, l2_index, ret; |
52d893ec | 754 | uint64_t l2_offset, *l2_table; |
108534b9 AL |
755 | |
756 | /* seek the the l2 offset in the l1 table */ | |
3b46e624 | 757 | |
585f8587 FB |
758 | l1_index = offset >> (s->l2_bits + s->cluster_bits); |
759 | if (l1_index >= s->l1_size) { | |
108534b9 AL |
760 | ret = grow_l1_table(bs, l1_index + 1); |
761 | if (ret < 0) | |
585f8587 FB |
762 | return 0; |
763 | } | |
764 | l2_offset = s->l1_table[l1_index]; | |
108534b9 AL |
765 | |
766 | /* seek the l2 table of the given l2 offset */ | |
767 | ||
05203524 AL |
768 | if (l2_offset & QCOW_OFLAG_COPIED) { |
769 | /* load the l2 table in memory */ | |
770 | l2_offset &= ~QCOW_OFLAG_COPIED; | |
771 | l2_table = l2_load(bs, l2_offset); | |
772 | if (l2_table == NULL) | |
585f8587 | 773 | return 0; |
05203524 AL |
774 | } else { |
775 | if (l2_offset) | |
776 | free_clusters(bs, l2_offset, s->l2_size * sizeof(uint64_t)); | |
108534b9 AL |
777 | l2_table = l2_allocate(bs, l1_index); |
778 | if (l2_table == NULL) | |
585f8587 | 779 | return 0; |
108534b9 | 780 | l2_offset = s->l1_table[l1_index] & ~QCOW_OFLAG_COPIED; |
585f8587 | 781 | } |
108534b9 AL |
782 | |
783 | /* find the cluster offset for the given disk offset */ | |
784 | ||
585f8587 | 785 | l2_index = (offset >> s->cluster_bits) & (s->l2_size - 1); |
05203524 | 786 | |
52d893ec AL |
787 | *new_l2_table = l2_table; |
788 | *new_l2_offset = l2_offset; | |
789 | *new_l2_index = l2_index; | |
790 | ||
791 | return 1; | |
792 | } | |
793 | ||
794 | /* | |
795 | * alloc_compressed_cluster_offset | |
796 | * | |
797 | * For a given offset of the disk image, return cluster offset in | |
798 | * qcow2 file. | |
799 | * | |
800 | * If the offset is not found, allocate a new compressed cluster. | |
801 | * | |
802 | * Return the cluster offset if successful, | |
803 | * Return 0, otherwise. | |
804 | * | |
805 | */ | |
806 | ||
807 | static uint64_t alloc_compressed_cluster_offset(BlockDriverState *bs, | |
808 | uint64_t offset, | |
809 | int compressed_size) | |
810 | { | |
811 | BDRVQcowState *s = bs->opaque; | |
812 | int l2_index, ret; | |
813 | uint64_t l2_offset, *l2_table, cluster_offset; | |
814 | int nb_csectors; | |
815 | ||
816 | ret = get_cluster_table(bs, offset, &l2_table, &l2_offset, &l2_index); | |
817 | if (ret == 0) | |
818 | return 0; | |
819 | ||
820 | cluster_offset = be64_to_cpu(l2_table[l2_index]); | |
05203524 AL |
821 | if (cluster_offset & QCOW_OFLAG_COPIED) |
822 | return cluster_offset & ~QCOW_OFLAG_COPIED; | |
823 | ||
095a9c58 AL |
824 | if (cluster_offset) |
825 | free_any_clusters(bs, cluster_offset, 1); | |
108534b9 | 826 | |
52d893ec AL |
827 | cluster_offset = alloc_bytes(bs, compressed_size); |
828 | nb_csectors = ((cluster_offset + compressed_size - 1) >> 9) - | |
829 | (cluster_offset >> 9); | |
05203524 | 830 | |
52d893ec AL |
831 | cluster_offset |= QCOW_OFLAG_COMPRESSED | |
832 | ((uint64_t)nb_csectors << s->csize_shift); | |
05203524 | 833 | |
52d893ec | 834 | /* update L2 table */ |
05203524 | 835 | |
52d893ec | 836 | /* compressed clusters never have the copied flag */ |
05203524 | 837 | |
52d893ec AL |
838 | l2_table[l2_index] = cpu_to_be64(cluster_offset); |
839 | if (bdrv_pwrite(s->hd, | |
840 | l2_offset + l2_index * sizeof(uint64_t), | |
841 | l2_table + l2_index, | |
842 | sizeof(uint64_t)) != sizeof(uint64_t)) | |
843 | return 0; | |
05203524 | 844 | |
52d893ec AL |
845 | return cluster_offset; |
846 | } | |
05203524 | 847 | |
52d893ec AL |
848 | /* |
849 | * alloc_cluster_offset | |
850 | * | |
851 | * For a given offset of the disk image, return cluster offset in | |
852 | * qcow2 file. | |
853 | * | |
854 | * If the offset is not found, allocate a new cluster. | |
855 | * | |
856 | * Return the cluster offset if successful, | |
857 | * Return 0, otherwise. | |
858 | * | |
859 | */ | |
860 | ||
861 | static uint64_t alloc_cluster_offset(BlockDriverState *bs, | |
862 | uint64_t offset, | |
095a9c58 AL |
863 | int n_start, int n_end, |
864 | int *num) | |
52d893ec AL |
865 | { |
866 | BDRVQcowState *s = bs->opaque; | |
867 | int l2_index, ret; | |
868 | uint64_t l2_offset, *l2_table, cluster_offset; | |
bc352085 | 869 | int nb_available, nb_clusters, i, j; |
095a9c58 | 870 | uint64_t start_sect, current; |
52d893ec AL |
871 | |
872 | ret = get_cluster_table(bs, offset, &l2_table, &l2_offset, &l2_index); | |
873 | if (ret == 0) | |
874 | return 0; | |
875 | ||
095a9c58 AL |
876 | nb_clusters = ((n_end << 9) + s->cluster_size - 1) >> |
877 | s->cluster_bits; | |
878 | if (nb_clusters > s->l2_size - l2_index) | |
879 | nb_clusters = s->l2_size - l2_index; | |
880 | ||
52d893ec | 881 | cluster_offset = be64_to_cpu(l2_table[l2_index]); |
52d893ec | 882 | |
095a9c58 AL |
883 | /* We keep all QCOW_OFLAG_COPIED clusters */ |
884 | ||
885 | if (cluster_offset & QCOW_OFLAG_COPIED) { | |
886 | ||
887 | for (i = 1; i < nb_clusters; i++) { | |
888 | current = be64_to_cpu(l2_table[l2_index + i]); | |
889 | if (cluster_offset + (i << s->cluster_bits) != current) | |
890 | break; | |
891 | } | |
892 | nb_clusters = i; | |
893 | ||
894 | nb_available = nb_clusters << (s->cluster_bits - 9); | |
895 | if (nb_available > n_end) | |
896 | nb_available = n_end; | |
897 | ||
898 | cluster_offset &= ~QCOW_OFLAG_COPIED; | |
899 | ||
900 | goto out; | |
901 | } | |
902 | ||
903 | /* for the moment, multiple compressed clusters are not managed */ | |
904 | ||
905 | if (cluster_offset & QCOW_OFLAG_COMPRESSED) | |
906 | nb_clusters = 1; | |
907 | ||
bc352085 | 908 | /* how many available clusters ? */ |
095a9c58 | 909 | |
bc352085 AL |
910 | i = 0; |
911 | while (i < nb_clusters) { | |
095a9c58 | 912 | |
bc352085 | 913 | i++; |
095a9c58 | 914 | |
bc352085 | 915 | if (!cluster_offset) { |
095a9c58 | 916 | |
bc352085 | 917 | /* how many free clusters ? */ |
095a9c58 | 918 | |
bc352085 | 919 | while (i < nb_clusters) { |
f4af02ed | 920 | cluster_offset = be64_to_cpu(l2_table[l2_index + i]); |
bc352085 AL |
921 | if (cluster_offset != 0) |
922 | break; | |
923 | i++; | |
924 | } | |
095a9c58 | 925 | |
bc352085 AL |
926 | if ((cluster_offset & QCOW_OFLAG_COPIED) || |
927 | (cluster_offset & QCOW_OFLAG_COMPRESSED)) | |
095a9c58 | 928 | break; |
095a9c58 | 929 | |
bc352085 AL |
930 | } else { |
931 | ||
932 | /* how many contiguous clusters ? */ | |
933 | ||
934 | j = 1; | |
935 | current = 0; | |
936 | while (i < nb_clusters) { | |
937 | current = be64_to_cpu(l2_table[l2_index + i]); | |
938 | if (cluster_offset + (j << s->cluster_bits) != current) | |
939 | break; | |
940 | ||
941 | i++; | |
942 | j++; | |
943 | } | |
944 | ||
945 | free_any_clusters(bs, cluster_offset, j); | |
946 | if (current) | |
947 | break; | |
948 | cluster_offset = current; | |
949 | } | |
095a9c58 | 950 | } |
bc352085 | 951 | nb_clusters = i; |
05203524 AL |
952 | |
953 | /* allocate a new cluster */ | |
954 | ||
095a9c58 | 955 | cluster_offset = alloc_clusters(bs, nb_clusters * s->cluster_size); |
05203524 AL |
956 | |
957 | /* we must initialize the cluster content which won't be | |
958 | written */ | |
959 | ||
095a9c58 AL |
960 | nb_available = nb_clusters << (s->cluster_bits - 9); |
961 | if (nb_available > n_end) | |
962 | nb_available = n_end; | |
05203524 | 963 | |
095a9c58 AL |
964 | /* copy content of unmodified sectors */ |
965 | ||
966 | start_sect = (offset & ~(s->cluster_size - 1)) >> 9; | |
967 | if (n_start) { | |
968 | ret = copy_sectors(bs, start_sect, cluster_offset, 0, n_start); | |
05203524 AL |
969 | if (ret < 0) |
970 | return 0; | |
095a9c58 AL |
971 | } |
972 | ||
973 | if (nb_available & (s->cluster_sectors - 1)) { | |
974 | uint64_t end = nb_available & ~(uint64_t)(s->cluster_sectors - 1); | |
975 | ret = copy_sectors(bs, start_sect + end, | |
976 | cluster_offset + (end << 9), | |
977 | nb_available - end, | |
978 | s->cluster_sectors); | |
05203524 AL |
979 | if (ret < 0) |
980 | return 0; | |
585f8587 | 981 | } |
05203524 | 982 | |
585f8587 | 983 | /* update L2 table */ |
05203524 | 984 | |
095a9c58 AL |
985 | for (i = 0; i < nb_clusters; i++) |
986 | l2_table[l2_index + i] = cpu_to_be64((cluster_offset + | |
987 | (i << s->cluster_bits)) | | |
988 | QCOW_OFLAG_COPIED); | |
989 | ||
5fafdf24 | 990 | if (bdrv_pwrite(s->hd, |
05203524 AL |
991 | l2_offset + l2_index * sizeof(uint64_t), |
992 | l2_table + l2_index, | |
095a9c58 AL |
993 | nb_clusters * sizeof(uint64_t)) != |
994 | nb_clusters * sizeof(uint64_t)) | |
585f8587 | 995 | return 0; |
05203524 | 996 | |
095a9c58 AL |
997 | out: |
998 | *num = nb_available - n_start; | |
999 | ||
585f8587 FB |
1000 | return cluster_offset; |
1001 | } | |
1002 | ||
5fafdf24 | 1003 | static int qcow_is_allocated(BlockDriverState *bs, int64_t sector_num, |
585f8587 FB |
1004 | int nb_sectors, int *pnum) |
1005 | { | |
585f8587 FB |
1006 | uint64_t cluster_offset; |
1007 | ||
095a9c58 AL |
1008 | *pnum = nb_sectors; |
1009 | cluster_offset = get_cluster_offset(bs, sector_num << 9, pnum); | |
1010 | ||
585f8587 FB |
1011 | return (cluster_offset != 0); |
1012 | } | |
1013 | ||
1014 | static int decompress_buffer(uint8_t *out_buf, int out_buf_size, | |
1015 | const uint8_t *buf, int buf_size) | |
1016 | { | |
1017 | z_stream strm1, *strm = &strm1; | |
1018 | int ret, out_len; | |
1019 | ||
1020 | memset(strm, 0, sizeof(*strm)); | |
1021 | ||
1022 | strm->next_in = (uint8_t *)buf; | |
1023 | strm->avail_in = buf_size; | |
1024 | strm->next_out = out_buf; | |
1025 | strm->avail_out = out_buf_size; | |
1026 | ||
1027 | ret = inflateInit2(strm, -12); | |
1028 | if (ret != Z_OK) | |
1029 | return -1; | |
1030 | ret = inflate(strm, Z_FINISH); | |
1031 | out_len = strm->next_out - out_buf; | |
1032 | if ((ret != Z_STREAM_END && ret != Z_BUF_ERROR) || | |
1033 | out_len != out_buf_size) { | |
1034 | inflateEnd(strm); | |
1035 | return -1; | |
1036 | } | |
1037 | inflateEnd(strm); | |
1038 | return 0; | |
1039 | } | |
3b46e624 | 1040 | |
585f8587 FB |
1041 | static int decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset) |
1042 | { | |
1043 | int ret, csize, nb_csectors, sector_offset; | |
1044 | uint64_t coffset; | |
1045 | ||
1046 | coffset = cluster_offset & s->cluster_offset_mask; | |
1047 | if (s->cluster_cache_offset != coffset) { | |
1048 | nb_csectors = ((cluster_offset >> s->csize_shift) & s->csize_mask) + 1; | |
1049 | sector_offset = coffset & 511; | |
1050 | csize = nb_csectors * 512 - sector_offset; | |
1051 | ret = bdrv_read(s->hd, coffset >> 9, s->cluster_data, nb_csectors); | |
1052 | if (ret < 0) { | |
1053 | return -1; | |
1054 | } | |
1055 | if (decompress_buffer(s->cluster_cache, s->cluster_size, | |
1056 | s->cluster_data + sector_offset, csize) < 0) { | |
1057 | return -1; | |
1058 | } | |
1059 | s->cluster_cache_offset = coffset; | |
1060 | } | |
1061 | return 0; | |
1062 | } | |
1063 | ||
a9465922 | 1064 | /* handle reading after the end of the backing file */ |
5fafdf24 | 1065 | static int backing_read1(BlockDriverState *bs, |
a9465922 FB |
1066 | int64_t sector_num, uint8_t *buf, int nb_sectors) |
1067 | { | |
1068 | int n1; | |
1069 | if ((sector_num + nb_sectors) <= bs->total_sectors) | |
1070 | return nb_sectors; | |
1071 | if (sector_num >= bs->total_sectors) | |
1072 | n1 = 0; | |
1073 | else | |
1074 | n1 = bs->total_sectors - sector_num; | |
1075 | memset(buf + n1 * 512, 0, 512 * (nb_sectors - n1)); | |
1076 | return n1; | |
1077 | } | |
1078 | ||
5fafdf24 | 1079 | static int qcow_read(BlockDriverState *bs, int64_t sector_num, |
585f8587 FB |
1080 | uint8_t *buf, int nb_sectors) |
1081 | { | |
1082 | BDRVQcowState *s = bs->opaque; | |
a9465922 | 1083 | int ret, index_in_cluster, n, n1; |
585f8587 | 1084 | uint64_t cluster_offset; |
3b46e624 | 1085 | |
585f8587 | 1086 | while (nb_sectors > 0) { |
095a9c58 AL |
1087 | n = nb_sectors; |
1088 | cluster_offset = get_cluster_offset(bs, sector_num << 9, &n); | |
585f8587 | 1089 | index_in_cluster = sector_num & (s->cluster_sectors - 1); |
585f8587 FB |
1090 | if (!cluster_offset) { |
1091 | if (bs->backing_hd) { | |
1092 | /* read from the base image */ | |
a9465922 FB |
1093 | n1 = backing_read1(bs->backing_hd, sector_num, buf, n); |
1094 | if (n1 > 0) { | |
1095 | ret = bdrv_read(bs->backing_hd, sector_num, buf, n1); | |
1096 | if (ret < 0) | |
1097 | return -1; | |
1098 | } | |
585f8587 FB |
1099 | } else { |
1100 | memset(buf, 0, 512 * n); | |
1101 | } | |
1102 | } else if (cluster_offset & QCOW_OFLAG_COMPRESSED) { | |
1103 | if (decompress_cluster(s, cluster_offset) < 0) | |
1104 | return -1; | |
1105 | memcpy(buf, s->cluster_cache + index_in_cluster * 512, 512 * n); | |
1106 | } else { | |
1107 | ret = bdrv_pread(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512); | |
5fafdf24 | 1108 | if (ret != n * 512) |
585f8587 FB |
1109 | return -1; |
1110 | if (s->crypt_method) { | |
5fafdf24 | 1111 | encrypt_sectors(s, sector_num, buf, buf, n, 0, |
585f8587 FB |
1112 | &s->aes_decrypt_key); |
1113 | } | |
1114 | } | |
1115 | nb_sectors -= n; | |
1116 | sector_num += n; | |
1117 | buf += n * 512; | |
1118 | } | |
1119 | return 0; | |
1120 | } | |
1121 | ||
5fafdf24 | 1122 | static int qcow_write(BlockDriverState *bs, int64_t sector_num, |
585f8587 FB |
1123 | const uint8_t *buf, int nb_sectors) |
1124 | { | |
1125 | BDRVQcowState *s = bs->opaque; | |
1126 | int ret, index_in_cluster, n; | |
1127 | uint64_t cluster_offset; | |
095a9c58 | 1128 | int n_end; |
3b46e624 | 1129 | |
585f8587 FB |
1130 | while (nb_sectors > 0) { |
1131 | index_in_cluster = sector_num & (s->cluster_sectors - 1); | |
095a9c58 AL |
1132 | n_end = index_in_cluster + nb_sectors; |
1133 | if (s->crypt_method && | |
1134 | n_end > QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors) | |
1135 | n_end = QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors; | |
52d893ec | 1136 | cluster_offset = alloc_cluster_offset(bs, sector_num << 9, |
05203524 | 1137 | index_in_cluster, |
095a9c58 | 1138 | n_end, &n); |
585f8587 FB |
1139 | if (!cluster_offset) |
1140 | return -1; | |
1141 | if (s->crypt_method) { | |
1142 | encrypt_sectors(s, sector_num, s->cluster_data, buf, n, 1, | |
1143 | &s->aes_encrypt_key); | |
5fafdf24 | 1144 | ret = bdrv_pwrite(s->hd, cluster_offset + index_in_cluster * 512, |
585f8587 FB |
1145 | s->cluster_data, n * 512); |
1146 | } else { | |
1147 | ret = bdrv_pwrite(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512); | |
1148 | } | |
5fafdf24 | 1149 | if (ret != n * 512) |
585f8587 FB |
1150 | return -1; |
1151 | nb_sectors -= n; | |
1152 | sector_num += n; | |
1153 | buf += n * 512; | |
1154 | } | |
1155 | s->cluster_cache_offset = -1; /* disable compressed cache */ | |
1156 | return 0; | |
1157 | } | |
1158 | ||
ce1a14dc PB |
1159 | typedef struct QCowAIOCB { |
1160 | BlockDriverAIOCB common; | |
585f8587 FB |
1161 | int64_t sector_num; |
1162 | uint8_t *buf; | |
1163 | int nb_sectors; | |
1164 | int n; | |
1165 | uint64_t cluster_offset; | |
5fafdf24 | 1166 | uint8_t *cluster_data; |
585f8587 | 1167 | BlockDriverAIOCB *hd_aiocb; |
585f8587 FB |
1168 | } QCowAIOCB; |
1169 | ||
585f8587 FB |
1170 | static void qcow_aio_read_cb(void *opaque, int ret) |
1171 | { | |
ce1a14dc PB |
1172 | QCowAIOCB *acb = opaque; |
1173 | BlockDriverState *bs = acb->common.bs; | |
585f8587 | 1174 | BDRVQcowState *s = bs->opaque; |
a9465922 | 1175 | int index_in_cluster, n1; |
585f8587 | 1176 | |
ce1a14dc | 1177 | acb->hd_aiocb = NULL; |
585f8587 FB |
1178 | if (ret < 0) { |
1179 | fail: | |
ce1a14dc PB |
1180 | acb->common.cb(acb->common.opaque, ret); |
1181 | qemu_aio_release(acb); | |
585f8587 FB |
1182 | return; |
1183 | } | |
1184 | ||
1185 | redo: | |
1186 | /* post process the read buffer */ | |
ce1a14dc | 1187 | if (!acb->cluster_offset) { |
585f8587 | 1188 | /* nothing to do */ |
ce1a14dc | 1189 | } else if (acb->cluster_offset & QCOW_OFLAG_COMPRESSED) { |
585f8587 FB |
1190 | /* nothing to do */ |
1191 | } else { | |
1192 | if (s->crypt_method) { | |
5fafdf24 TS |
1193 | encrypt_sectors(s, acb->sector_num, acb->buf, acb->buf, |
1194 | acb->n, 0, | |
585f8587 FB |
1195 | &s->aes_decrypt_key); |
1196 | } | |
1197 | } | |
1198 | ||
ce1a14dc PB |
1199 | acb->nb_sectors -= acb->n; |
1200 | acb->sector_num += acb->n; | |
1201 | acb->buf += acb->n * 512; | |
585f8587 | 1202 | |
ce1a14dc | 1203 | if (acb->nb_sectors == 0) { |
585f8587 | 1204 | /* request completed */ |
ce1a14dc PB |
1205 | acb->common.cb(acb->common.opaque, 0); |
1206 | qemu_aio_release(acb); | |
585f8587 FB |
1207 | return; |
1208 | } | |
3b46e624 | 1209 | |
585f8587 | 1210 | /* prepare next AIO request */ |
095a9c58 AL |
1211 | acb->n = acb->nb_sectors; |
1212 | acb->cluster_offset = get_cluster_offset(bs, acb->sector_num << 9, &acb->n); | |
ce1a14dc | 1213 | index_in_cluster = acb->sector_num & (s->cluster_sectors - 1); |
ce1a14dc PB |
1214 | |
1215 | if (!acb->cluster_offset) { | |
585f8587 FB |
1216 | if (bs->backing_hd) { |
1217 | /* read from the base image */ | |
5fafdf24 | 1218 | n1 = backing_read1(bs->backing_hd, acb->sector_num, |
ce1a14dc | 1219 | acb->buf, acb->n); |
a9465922 | 1220 | if (n1 > 0) { |
5fafdf24 | 1221 | acb->hd_aiocb = bdrv_aio_read(bs->backing_hd, acb->sector_num, |
ce1a14dc PB |
1222 | acb->buf, acb->n, qcow_aio_read_cb, acb); |
1223 | if (acb->hd_aiocb == NULL) | |
a9465922 FB |
1224 | goto fail; |
1225 | } else { | |
1226 | goto redo; | |
1227 | } | |
585f8587 FB |
1228 | } else { |
1229 | /* Note: in this case, no need to wait */ | |
ce1a14dc | 1230 | memset(acb->buf, 0, 512 * acb->n); |
585f8587 FB |
1231 | goto redo; |
1232 | } | |
ce1a14dc | 1233 | } else if (acb->cluster_offset & QCOW_OFLAG_COMPRESSED) { |
585f8587 | 1234 | /* add AIO support for compressed blocks ? */ |
ce1a14dc | 1235 | if (decompress_cluster(s, acb->cluster_offset) < 0) |
585f8587 | 1236 | goto fail; |
5fafdf24 | 1237 | memcpy(acb->buf, |
ce1a14dc | 1238 | s->cluster_cache + index_in_cluster * 512, 512 * acb->n); |
585f8587 FB |
1239 | goto redo; |
1240 | } else { | |
ce1a14dc | 1241 | if ((acb->cluster_offset & 511) != 0) { |
585f8587 FB |
1242 | ret = -EIO; |
1243 | goto fail; | |
1244 | } | |
ce1a14dc | 1245 | acb->hd_aiocb = bdrv_aio_read(s->hd, |
5fafdf24 | 1246 | (acb->cluster_offset >> 9) + index_in_cluster, |
ce1a14dc PB |
1247 | acb->buf, acb->n, qcow_aio_read_cb, acb); |
1248 | if (acb->hd_aiocb == NULL) | |
585f8587 FB |
1249 | goto fail; |
1250 | } | |
1251 | } | |
1252 | ||
ce1a14dc PB |
1253 | static QCowAIOCB *qcow_aio_setup(BlockDriverState *bs, |
1254 | int64_t sector_num, uint8_t *buf, int nb_sectors, | |
1255 | BlockDriverCompletionFunc *cb, void *opaque) | |
585f8587 | 1256 | { |
ce1a14dc PB |
1257 | QCowAIOCB *acb; |
1258 | ||
1259 | acb = qemu_aio_get(bs, cb, opaque); | |
1260 | if (!acb) | |
1261 | return NULL; | |
1262 | acb->hd_aiocb = NULL; | |
1263 | acb->sector_num = sector_num; | |
1264 | acb->buf = buf; | |
1265 | acb->nb_sectors = nb_sectors; | |
1266 | acb->n = 0; | |
1267 | acb->cluster_offset = 0; | |
1268 | return acb; | |
1269 | } | |
1270 | ||
1271 | static BlockDriverAIOCB *qcow_aio_read(BlockDriverState *bs, | |
1272 | int64_t sector_num, uint8_t *buf, int nb_sectors, | |
1273 | BlockDriverCompletionFunc *cb, void *opaque) | |
1274 | { | |
1275 | QCowAIOCB *acb; | |
1276 | ||
1277 | acb = qcow_aio_setup(bs, sector_num, buf, nb_sectors, cb, opaque); | |
1278 | if (!acb) | |
1279 | return NULL; | |
585f8587 FB |
1280 | |
1281 | qcow_aio_read_cb(acb, 0); | |
ce1a14dc | 1282 | return &acb->common; |
585f8587 FB |
1283 | } |
1284 | ||
1285 | static void qcow_aio_write_cb(void *opaque, int ret) | |
1286 | { | |
ce1a14dc PB |
1287 | QCowAIOCB *acb = opaque; |
1288 | BlockDriverState *bs = acb->common.bs; | |
585f8587 | 1289 | BDRVQcowState *s = bs->opaque; |
585f8587 FB |
1290 | int index_in_cluster; |
1291 | uint64_t cluster_offset; | |
1292 | const uint8_t *src_buf; | |
095a9c58 | 1293 | int n_end; |
ce1a14dc PB |
1294 | |
1295 | acb->hd_aiocb = NULL; | |
1296 | ||
585f8587 FB |
1297 | if (ret < 0) { |
1298 | fail: | |
ce1a14dc PB |
1299 | acb->common.cb(acb->common.opaque, ret); |
1300 | qemu_aio_release(acb); | |
585f8587 FB |
1301 | return; |
1302 | } | |
1303 | ||
ce1a14dc PB |
1304 | acb->nb_sectors -= acb->n; |
1305 | acb->sector_num += acb->n; | |
1306 | acb->buf += acb->n * 512; | |
585f8587 | 1307 | |
ce1a14dc | 1308 | if (acb->nb_sectors == 0) { |
585f8587 | 1309 | /* request completed */ |
ce1a14dc PB |
1310 | acb->common.cb(acb->common.opaque, 0); |
1311 | qemu_aio_release(acb); | |
585f8587 FB |
1312 | return; |
1313 | } | |
3b46e624 | 1314 | |
ce1a14dc | 1315 | index_in_cluster = acb->sector_num & (s->cluster_sectors - 1); |
095a9c58 AL |
1316 | n_end = index_in_cluster + acb->nb_sectors; |
1317 | if (s->crypt_method && | |
1318 | n_end > QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors) | |
1319 | n_end = QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors; | |
1320 | ||
52d893ec | 1321 | cluster_offset = alloc_cluster_offset(bs, acb->sector_num << 9, |
05203524 | 1322 | index_in_cluster, |
095a9c58 | 1323 | n_end, &acb->n); |
585f8587 FB |
1324 | if (!cluster_offset || (cluster_offset & 511) != 0) { |
1325 | ret = -EIO; | |
1326 | goto fail; | |
1327 | } | |
1328 | if (s->crypt_method) { | |
ce1a14dc | 1329 | if (!acb->cluster_data) { |
095a9c58 AL |
1330 | acb->cluster_data = qemu_mallocz(QCOW_MAX_CRYPT_CLUSTERS * |
1331 | s->cluster_size); | |
ce1a14dc | 1332 | if (!acb->cluster_data) { |
585f8587 FB |
1333 | ret = -ENOMEM; |
1334 | goto fail; | |
1335 | } | |
1336 | } | |
5fafdf24 | 1337 | encrypt_sectors(s, acb->sector_num, acb->cluster_data, acb->buf, |
ce1a14dc PB |
1338 | acb->n, 1, &s->aes_encrypt_key); |
1339 | src_buf = acb->cluster_data; | |
585f8587 | 1340 | } else { |
ce1a14dc | 1341 | src_buf = acb->buf; |
585f8587 | 1342 | } |
ce1a14dc | 1343 | acb->hd_aiocb = bdrv_aio_write(s->hd, |
5fafdf24 TS |
1344 | (cluster_offset >> 9) + index_in_cluster, |
1345 | src_buf, acb->n, | |
ce1a14dc PB |
1346 | qcow_aio_write_cb, acb); |
1347 | if (acb->hd_aiocb == NULL) | |
585f8587 FB |
1348 | goto fail; |
1349 | } | |
1350 | ||
ce1a14dc PB |
1351 | static BlockDriverAIOCB *qcow_aio_write(BlockDriverState *bs, |
1352 | int64_t sector_num, const uint8_t *buf, int nb_sectors, | |
1353 | BlockDriverCompletionFunc *cb, void *opaque) | |
585f8587 | 1354 | { |
585f8587 | 1355 | BDRVQcowState *s = bs->opaque; |
ce1a14dc | 1356 | QCowAIOCB *acb; |
3b46e624 | 1357 | |
585f8587 FB |
1358 | s->cluster_cache_offset = -1; /* disable compressed cache */ |
1359 | ||
ce1a14dc PB |
1360 | acb = qcow_aio_setup(bs, sector_num, (uint8_t*)buf, nb_sectors, cb, opaque); |
1361 | if (!acb) | |
1362 | return NULL; | |
3b46e624 | 1363 | |
585f8587 | 1364 | qcow_aio_write_cb(acb, 0); |
ce1a14dc | 1365 | return &acb->common; |
585f8587 FB |
1366 | } |
1367 | ||
ce1a14dc | 1368 | static void qcow_aio_cancel(BlockDriverAIOCB *blockacb) |
585f8587 | 1369 | { |
ce1a14dc PB |
1370 | QCowAIOCB *acb = (QCowAIOCB *)blockacb; |
1371 | if (acb->hd_aiocb) | |
1372 | bdrv_aio_cancel(acb->hd_aiocb); | |
1373 | qemu_aio_release(acb); | |
585f8587 FB |
1374 | } |
1375 | ||
1376 | static void qcow_close(BlockDriverState *bs) | |
1377 | { | |
1378 | BDRVQcowState *s = bs->opaque; | |
1379 | qemu_free(s->l1_table); | |
1380 | qemu_free(s->l2_cache); | |
1381 | qemu_free(s->cluster_cache); | |
1382 | qemu_free(s->cluster_data); | |
1383 | refcount_close(bs); | |
1384 | bdrv_delete(s->hd); | |
1385 | } | |
1386 | ||
1387 | /* XXX: use std qcow open function ? */ | |
1388 | typedef struct QCowCreateState { | |
1389 | int cluster_size; | |
1390 | int cluster_bits; | |
1391 | uint16_t *refcount_block; | |
1392 | uint64_t *refcount_table; | |
1393 | int64_t l1_table_offset; | |
1394 | int64_t refcount_table_offset; | |
1395 | int64_t refcount_block_offset; | |
1396 | } QCowCreateState; | |
1397 | ||
1398 | static void create_refcount_update(QCowCreateState *s, | |
1399 | int64_t offset, int64_t size) | |
1400 | { | |
1401 | int refcount; | |
1402 | int64_t start, last, cluster_offset; | |
1403 | uint16_t *p; | |
1404 | ||
1405 | start = offset & ~(s->cluster_size - 1); | |
1406 | last = (offset + size - 1) & ~(s->cluster_size - 1); | |
5fafdf24 | 1407 | for(cluster_offset = start; cluster_offset <= last; |
585f8587 FB |
1408 | cluster_offset += s->cluster_size) { |
1409 | p = &s->refcount_block[cluster_offset >> s->cluster_bits]; | |
1410 | refcount = be16_to_cpu(*p); | |
1411 | refcount++; | |
1412 | *p = cpu_to_be16(refcount); | |
1413 | } | |
1414 | } | |
1415 | ||
1416 | static int qcow_create(const char *filename, int64_t total_size, | |
1417 | const char *backing_file, int flags) | |
1418 | { | |
1419 | int fd, header_size, backing_filename_len, l1_size, i, shift, l2_bits; | |
1420 | QCowHeader header; | |
1421 | uint64_t tmp, offset; | |
1422 | QCowCreateState s1, *s = &s1; | |
3b46e624 | 1423 | |
585f8587 FB |
1424 | memset(s, 0, sizeof(*s)); |
1425 | ||
1426 | fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, 0644); | |
1427 | if (fd < 0) | |
1428 | return -1; | |
1429 | memset(&header, 0, sizeof(header)); | |
1430 | header.magic = cpu_to_be32(QCOW_MAGIC); | |
1431 | header.version = cpu_to_be32(QCOW_VERSION); | |
1432 | header.size = cpu_to_be64(total_size * 512); | |
1433 | header_size = sizeof(header); | |
1434 | backing_filename_len = 0; | |
1435 | if (backing_file) { | |
1436 | header.backing_file_offset = cpu_to_be64(header_size); | |
1437 | backing_filename_len = strlen(backing_file); | |
1438 | header.backing_file_size = cpu_to_be32(backing_filename_len); | |
1439 | header_size += backing_filename_len; | |
1440 | } | |
1441 | s->cluster_bits = 12; /* 4 KB clusters */ | |
1442 | s->cluster_size = 1 << s->cluster_bits; | |
1443 | header.cluster_bits = cpu_to_be32(s->cluster_bits); | |
1444 | header_size = (header_size + 7) & ~7; | |
ec36ba14 | 1445 | if (flags & BLOCK_FLAG_ENCRYPT) { |
585f8587 FB |
1446 | header.crypt_method = cpu_to_be32(QCOW_CRYPT_AES); |
1447 | } else { | |
1448 | header.crypt_method = cpu_to_be32(QCOW_CRYPT_NONE); | |
1449 | } | |
1450 | l2_bits = s->cluster_bits - 3; | |
1451 | shift = s->cluster_bits + l2_bits; | |
1452 | l1_size = (((total_size * 512) + (1LL << shift) - 1) >> shift); | |
1453 | offset = align_offset(header_size, s->cluster_size); | |
1454 | s->l1_table_offset = offset; | |
1455 | header.l1_table_offset = cpu_to_be64(s->l1_table_offset); | |
1456 | header.l1_size = cpu_to_be32(l1_size); | |
15e6690a | 1457 | offset += align_offset(l1_size * sizeof(uint64_t), s->cluster_size); |
585f8587 FB |
1458 | |
1459 | s->refcount_table = qemu_mallocz(s->cluster_size); | |
1460 | if (!s->refcount_table) | |
1461 | goto fail; | |
1462 | s->refcount_block = qemu_mallocz(s->cluster_size); | |
1463 | if (!s->refcount_block) | |
1464 | goto fail; | |
3b46e624 | 1465 | |
585f8587 FB |
1466 | s->refcount_table_offset = offset; |
1467 | header.refcount_table_offset = cpu_to_be64(offset); | |
1468 | header.refcount_table_clusters = cpu_to_be32(1); | |
1469 | offset += s->cluster_size; | |
1470 | ||
1471 | s->refcount_table[0] = cpu_to_be64(offset); | |
1472 | s->refcount_block_offset = offset; | |
1473 | offset += s->cluster_size; | |
1474 | ||
1475 | /* update refcounts */ | |
1476 | create_refcount_update(s, 0, header_size); | |
15e6690a | 1477 | create_refcount_update(s, s->l1_table_offset, l1_size * sizeof(uint64_t)); |
585f8587 FB |
1478 | create_refcount_update(s, s->refcount_table_offset, s->cluster_size); |
1479 | create_refcount_update(s, s->refcount_block_offset, s->cluster_size); | |
3b46e624 | 1480 | |
585f8587 FB |
1481 | /* write all the data */ |
1482 | write(fd, &header, sizeof(header)); | |
1483 | if (backing_file) { | |
1484 | write(fd, backing_file, backing_filename_len); | |
1485 | } | |
1486 | lseek(fd, s->l1_table_offset, SEEK_SET); | |
1487 | tmp = 0; | |
1488 | for(i = 0;i < l1_size; i++) { | |
1489 | write(fd, &tmp, sizeof(tmp)); | |
1490 | } | |
1491 | lseek(fd, s->refcount_table_offset, SEEK_SET); | |
1492 | write(fd, s->refcount_table, s->cluster_size); | |
3b46e624 | 1493 | |
585f8587 FB |
1494 | lseek(fd, s->refcount_block_offset, SEEK_SET); |
1495 | write(fd, s->refcount_block, s->cluster_size); | |
1496 | ||
1497 | qemu_free(s->refcount_table); | |
1498 | qemu_free(s->refcount_block); | |
1499 | close(fd); | |
1500 | return 0; | |
1501 | fail: | |
1502 | qemu_free(s->refcount_table); | |
1503 | qemu_free(s->refcount_block); | |
1504 | close(fd); | |
1505 | return -ENOMEM; | |
1506 | } | |
1507 | ||
1508 | static int qcow_make_empty(BlockDriverState *bs) | |
1509 | { | |
1510 | #if 0 | |
1511 | /* XXX: not correct */ | |
1512 | BDRVQcowState *s = bs->opaque; | |
1513 | uint32_t l1_length = s->l1_size * sizeof(uint64_t); | |
1514 | int ret; | |
1515 | ||
1516 | memset(s->l1_table, 0, l1_length); | |
1517 | if (bdrv_pwrite(s->hd, s->l1_table_offset, s->l1_table, l1_length) < 0) | |
1518 | return -1; | |
1519 | ret = bdrv_truncate(s->hd, s->l1_table_offset + l1_length); | |
1520 | if (ret < 0) | |
1521 | return ret; | |
3b46e624 | 1522 | |
585f8587 FB |
1523 | l2_cache_reset(bs); |
1524 | #endif | |
1525 | return 0; | |
1526 | } | |
1527 | ||
1528 | /* XXX: put compressed sectors first, then all the cluster aligned | |
1529 | tables to avoid losing bytes in alignment */ | |
5fafdf24 | 1530 | static int qcow_write_compressed(BlockDriverState *bs, int64_t sector_num, |
585f8587 FB |
1531 | const uint8_t *buf, int nb_sectors) |
1532 | { | |
1533 | BDRVQcowState *s = bs->opaque; | |
1534 | z_stream strm; | |
1535 | int ret, out_len; | |
1536 | uint8_t *out_buf; | |
1537 | uint64_t cluster_offset; | |
1538 | ||
1539 | if (nb_sectors == 0) { | |
1540 | /* align end of file to a sector boundary to ease reading with | |
1541 | sector based I/Os */ | |
1542 | cluster_offset = bdrv_getlength(s->hd); | |
1543 | cluster_offset = (cluster_offset + 511) & ~511; | |
1544 | bdrv_truncate(s->hd, cluster_offset); | |
1545 | return 0; | |
1546 | } | |
1547 | ||
1548 | if (nb_sectors != s->cluster_sectors) | |
1549 | return -EINVAL; | |
1550 | ||
1551 | out_buf = qemu_malloc(s->cluster_size + (s->cluster_size / 1000) + 128); | |
1552 | if (!out_buf) | |
1553 | return -ENOMEM; | |
1554 | ||
1555 | /* best compression, small window, no zlib header */ | |
1556 | memset(&strm, 0, sizeof(strm)); | |
1557 | ret = deflateInit2(&strm, Z_DEFAULT_COMPRESSION, | |
5fafdf24 | 1558 | Z_DEFLATED, -12, |
585f8587 FB |
1559 | 9, Z_DEFAULT_STRATEGY); |
1560 | if (ret != 0) { | |
1561 | qemu_free(out_buf); | |
1562 | return -1; | |
1563 | } | |
1564 | ||
1565 | strm.avail_in = s->cluster_size; | |
1566 | strm.next_in = (uint8_t *)buf; | |
1567 | strm.avail_out = s->cluster_size; | |
1568 | strm.next_out = out_buf; | |
1569 | ||
1570 | ret = deflate(&strm, Z_FINISH); | |
1571 | if (ret != Z_STREAM_END && ret != Z_OK) { | |
1572 | qemu_free(out_buf); | |
1573 | deflateEnd(&strm); | |
1574 | return -1; | |
1575 | } | |
1576 | out_len = strm.next_out - out_buf; | |
1577 | ||
1578 | deflateEnd(&strm); | |
1579 | ||
1580 | if (ret != Z_STREAM_END || out_len >= s->cluster_size) { | |
1581 | /* could not compress: write normal cluster */ | |
1582 | qcow_write(bs, sector_num, buf, s->cluster_sectors); | |
1583 | } else { | |
52d893ec AL |
1584 | cluster_offset = alloc_compressed_cluster_offset(bs, sector_num << 9, |
1585 | out_len); | |
1586 | if (!cluster_offset) | |
1587 | return -1; | |
585f8587 FB |
1588 | cluster_offset &= s->cluster_offset_mask; |
1589 | if (bdrv_pwrite(s->hd, cluster_offset, out_buf, out_len) != out_len) { | |
1590 | qemu_free(out_buf); | |
1591 | return -1; | |
1592 | } | |
1593 | } | |
3b46e624 | 1594 | |
585f8587 FB |
1595 | qemu_free(out_buf); |
1596 | return 0; | |
1597 | } | |
1598 | ||
1599 | static void qcow_flush(BlockDriverState *bs) | |
1600 | { | |
1601 | BDRVQcowState *s = bs->opaque; | |
1602 | bdrv_flush(s->hd); | |
1603 | } | |
1604 | ||
1605 | static int qcow_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) | |
1606 | { | |
1607 | BDRVQcowState *s = bs->opaque; | |
1608 | bdi->cluster_size = s->cluster_size; | |
5fafdf24 | 1609 | bdi->vm_state_offset = (int64_t)s->l1_vm_state_index << |
585f8587 FB |
1610 | (s->cluster_bits + s->l2_bits); |
1611 | return 0; | |
1612 | } | |
1613 | ||
1614 | /*********************************************************/ | |
1615 | /* snapshot support */ | |
1616 | ||
1617 | /* update the refcounts of snapshots and the copied flag */ | |
5fafdf24 | 1618 | static int update_snapshot_refcount(BlockDriverState *bs, |
585f8587 FB |
1619 | int64_t l1_table_offset, |
1620 | int l1_size, | |
1621 | int addend) | |
1622 | { | |
1623 | BDRVQcowState *s = bs->opaque; | |
1624 | uint64_t *l1_table, *l2_table, l2_offset, offset, l1_size2, l1_allocated; | |
1625 | int64_t old_offset, old_l2_offset; | |
1626 | int l2_size, i, j, l1_modified, l2_modified, nb_csectors, refcount; | |
3b46e624 | 1627 | |
585f8587 FB |
1628 | l2_cache_reset(bs); |
1629 | ||
1630 | l2_table = NULL; | |
1631 | l1_table = NULL; | |
1632 | l1_size2 = l1_size * sizeof(uint64_t); | |
1633 | l1_allocated = 0; | |
1634 | if (l1_table_offset != s->l1_table_offset) { | |
1635 | l1_table = qemu_malloc(l1_size2); | |
1636 | if (!l1_table) | |
1637 | goto fail; | |
1638 | l1_allocated = 1; | |
5fafdf24 | 1639 | if (bdrv_pread(s->hd, l1_table_offset, |
585f8587 FB |
1640 | l1_table, l1_size2) != l1_size2) |
1641 | goto fail; | |
1642 | for(i = 0;i < l1_size; i++) | |
1643 | be64_to_cpus(&l1_table[i]); | |
1644 | } else { | |
1645 | assert(l1_size == s->l1_size); | |
1646 | l1_table = s->l1_table; | |
1647 | l1_allocated = 0; | |
1648 | } | |
3b46e624 | 1649 | |
585f8587 FB |
1650 | l2_size = s->l2_size * sizeof(uint64_t); |
1651 | l2_table = qemu_malloc(l2_size); | |
1652 | if (!l2_table) | |
1653 | goto fail; | |
1654 | l1_modified = 0; | |
1655 | for(i = 0; i < l1_size; i++) { | |
1656 | l2_offset = l1_table[i]; | |
1657 | if (l2_offset) { | |
1658 | old_l2_offset = l2_offset; | |
1659 | l2_offset &= ~QCOW_OFLAG_COPIED; | |
1660 | l2_modified = 0; | |
1661 | if (bdrv_pread(s->hd, l2_offset, l2_table, l2_size) != l2_size) | |
1662 | goto fail; | |
1663 | for(j = 0; j < s->l2_size; j++) { | |
1664 | offset = be64_to_cpu(l2_table[j]); | |
1665 | if (offset != 0) { | |
1666 | old_offset = offset; | |
1667 | offset &= ~QCOW_OFLAG_COPIED; | |
1668 | if (offset & QCOW_OFLAG_COMPRESSED) { | |
5fafdf24 | 1669 | nb_csectors = ((offset >> s->csize_shift) & |
585f8587 FB |
1670 | s->csize_mask) + 1; |
1671 | if (addend != 0) | |
1672 | update_refcount(bs, (offset & s->cluster_offset_mask) & ~511, | |
1673 | nb_csectors * 512, addend); | |
1674 | /* compressed clusters are never modified */ | |
5fafdf24 | 1675 | refcount = 2; |
585f8587 FB |
1676 | } else { |
1677 | if (addend != 0) { | |
1678 | refcount = update_cluster_refcount(bs, offset >> s->cluster_bits, addend); | |
1679 | } else { | |
1680 | refcount = get_refcount(bs, offset >> s->cluster_bits); | |
1681 | } | |
1682 | } | |
1683 | ||
1684 | if (refcount == 1) { | |
1685 | offset |= QCOW_OFLAG_COPIED; | |
1686 | } | |
1687 | if (offset != old_offset) { | |
1688 | l2_table[j] = cpu_to_be64(offset); | |
1689 | l2_modified = 1; | |
1690 | } | |
1691 | } | |
1692 | } | |
1693 | if (l2_modified) { | |
5fafdf24 | 1694 | if (bdrv_pwrite(s->hd, |
585f8587 FB |
1695 | l2_offset, l2_table, l2_size) != l2_size) |
1696 | goto fail; | |
1697 | } | |
1698 | ||
1699 | if (addend != 0) { | |
1700 | refcount = update_cluster_refcount(bs, l2_offset >> s->cluster_bits, addend); | |
1701 | } else { | |
1702 | refcount = get_refcount(bs, l2_offset >> s->cluster_bits); | |
1703 | } | |
1704 | if (refcount == 1) { | |
1705 | l2_offset |= QCOW_OFLAG_COPIED; | |
1706 | } | |
1707 | if (l2_offset != old_l2_offset) { | |
1708 | l1_table[i] = l2_offset; | |
1709 | l1_modified = 1; | |
1710 | } | |
1711 | } | |
1712 | } | |
1713 | if (l1_modified) { | |
1714 | for(i = 0; i < l1_size; i++) | |
1715 | cpu_to_be64s(&l1_table[i]); | |
5fafdf24 | 1716 | if (bdrv_pwrite(s->hd, l1_table_offset, l1_table, |
585f8587 FB |
1717 | l1_size2) != l1_size2) |
1718 | goto fail; | |
1719 | for(i = 0; i < l1_size; i++) | |
1720 | be64_to_cpus(&l1_table[i]); | |
1721 | } | |
1722 | if (l1_allocated) | |
1723 | qemu_free(l1_table); | |
1724 | qemu_free(l2_table); | |
1725 | return 0; | |
1726 | fail: | |
1727 | if (l1_allocated) | |
1728 | qemu_free(l1_table); | |
1729 | qemu_free(l2_table); | |
1730 | return -EIO; | |
1731 | } | |
1732 | ||
1733 | static void qcow_free_snapshots(BlockDriverState *bs) | |
1734 | { | |
1735 | BDRVQcowState *s = bs->opaque; | |
1736 | int i; | |
1737 | ||
1738 | for(i = 0; i < s->nb_snapshots; i++) { | |
1739 | qemu_free(s->snapshots[i].name); | |
1740 | qemu_free(s->snapshots[i].id_str); | |
1741 | } | |
1742 | qemu_free(s->snapshots); | |
1743 | s->snapshots = NULL; | |
1744 | s->nb_snapshots = 0; | |
1745 | } | |
1746 | ||
1747 | static int qcow_read_snapshots(BlockDriverState *bs) | |
1748 | { | |
1749 | BDRVQcowState *s = bs->opaque; | |
1750 | QCowSnapshotHeader h; | |
1751 | QCowSnapshot *sn; | |
1752 | int i, id_str_size, name_size; | |
1753 | int64_t offset; | |
1754 | uint32_t extra_data_size; | |
1755 | ||
1756 | offset = s->snapshots_offset; | |
1757 | s->snapshots = qemu_mallocz(s->nb_snapshots * sizeof(QCowSnapshot)); | |
1758 | if (!s->snapshots) | |
1759 | goto fail; | |
1760 | for(i = 0; i < s->nb_snapshots; i++) { | |
1761 | offset = align_offset(offset, 8); | |
1762 | if (bdrv_pread(s->hd, offset, &h, sizeof(h)) != sizeof(h)) | |
1763 | goto fail; | |
1764 | offset += sizeof(h); | |
1765 | sn = s->snapshots + i; | |
1766 | sn->l1_table_offset = be64_to_cpu(h.l1_table_offset); | |
1767 | sn->l1_size = be32_to_cpu(h.l1_size); | |
1768 | sn->vm_state_size = be32_to_cpu(h.vm_state_size); | |
1769 | sn->date_sec = be32_to_cpu(h.date_sec); | |
1770 | sn->date_nsec = be32_to_cpu(h.date_nsec); | |
1771 | sn->vm_clock_nsec = be64_to_cpu(h.vm_clock_nsec); | |
1772 | extra_data_size = be32_to_cpu(h.extra_data_size); | |
1773 | ||
1774 | id_str_size = be16_to_cpu(h.id_str_size); | |
1775 | name_size = be16_to_cpu(h.name_size); | |
1776 | ||
1777 | offset += extra_data_size; | |
1778 | ||
1779 | sn->id_str = qemu_malloc(id_str_size + 1); | |
1780 | if (!sn->id_str) | |
1781 | goto fail; | |
1782 | if (bdrv_pread(s->hd, offset, sn->id_str, id_str_size) != id_str_size) | |
1783 | goto fail; | |
1784 | offset += id_str_size; | |
1785 | sn->id_str[id_str_size] = '\0'; | |
1786 | ||
1787 | sn->name = qemu_malloc(name_size + 1); | |
1788 | if (!sn->name) | |
1789 | goto fail; | |
1790 | if (bdrv_pread(s->hd, offset, sn->name, name_size) != name_size) | |
1791 | goto fail; | |
1792 | offset += name_size; | |
1793 | sn->name[name_size] = '\0'; | |
1794 | } | |
1795 | s->snapshots_size = offset - s->snapshots_offset; | |
1796 | return 0; | |
1797 | fail: | |
1798 | qcow_free_snapshots(bs); | |
1799 | return -1; | |
1800 | } | |
1801 | ||
1802 | /* add at the end of the file a new list of snapshots */ | |
1803 | static int qcow_write_snapshots(BlockDriverState *bs) | |
1804 | { | |
1805 | BDRVQcowState *s = bs->opaque; | |
1806 | QCowSnapshot *sn; | |
1807 | QCowSnapshotHeader h; | |
1808 | int i, name_size, id_str_size, snapshots_size; | |
1809 | uint64_t data64; | |
1810 | uint32_t data32; | |
1811 | int64_t offset, snapshots_offset; | |
1812 | ||
1813 | /* compute the size of the snapshots */ | |
1814 | offset = 0; | |
1815 | for(i = 0; i < s->nb_snapshots; i++) { | |
1816 | sn = s->snapshots + i; | |
1817 | offset = align_offset(offset, 8); | |
1818 | offset += sizeof(h); | |
1819 | offset += strlen(sn->id_str); | |
1820 | offset += strlen(sn->name); | |
1821 | } | |
1822 | snapshots_size = offset; | |
1823 | ||
1824 | snapshots_offset = alloc_clusters(bs, snapshots_size); | |
1825 | offset = snapshots_offset; | |
3b46e624 | 1826 | |
585f8587 FB |
1827 | for(i = 0; i < s->nb_snapshots; i++) { |
1828 | sn = s->snapshots + i; | |
1829 | memset(&h, 0, sizeof(h)); | |
1830 | h.l1_table_offset = cpu_to_be64(sn->l1_table_offset); | |
1831 | h.l1_size = cpu_to_be32(sn->l1_size); | |
1832 | h.vm_state_size = cpu_to_be32(sn->vm_state_size); | |
1833 | h.date_sec = cpu_to_be32(sn->date_sec); | |
1834 | h.date_nsec = cpu_to_be32(sn->date_nsec); | |
1835 | h.vm_clock_nsec = cpu_to_be64(sn->vm_clock_nsec); | |
3b46e624 | 1836 | |
585f8587 FB |
1837 | id_str_size = strlen(sn->id_str); |
1838 | name_size = strlen(sn->name); | |
1839 | h.id_str_size = cpu_to_be16(id_str_size); | |
1840 | h.name_size = cpu_to_be16(name_size); | |
1841 | offset = align_offset(offset, 8); | |
1842 | if (bdrv_pwrite(s->hd, offset, &h, sizeof(h)) != sizeof(h)) | |
1843 | goto fail; | |
1844 | offset += sizeof(h); | |
1845 | if (bdrv_pwrite(s->hd, offset, sn->id_str, id_str_size) != id_str_size) | |
1846 | goto fail; | |
1847 | offset += id_str_size; | |
1848 | if (bdrv_pwrite(s->hd, offset, sn->name, name_size) != name_size) | |
1849 | goto fail; | |
1850 | offset += name_size; | |
1851 | } | |
1852 | ||
1853 | /* update the various header fields */ | |
1854 | data64 = cpu_to_be64(snapshots_offset); | |
1855 | if (bdrv_pwrite(s->hd, offsetof(QCowHeader, snapshots_offset), | |
1856 | &data64, sizeof(data64)) != sizeof(data64)) | |
1857 | goto fail; | |
1858 | data32 = cpu_to_be32(s->nb_snapshots); | |
1859 | if (bdrv_pwrite(s->hd, offsetof(QCowHeader, nb_snapshots), | |
1860 | &data32, sizeof(data32)) != sizeof(data32)) | |
1861 | goto fail; | |
1862 | ||
1863 | /* free the old snapshot table */ | |
1864 | free_clusters(bs, s->snapshots_offset, s->snapshots_size); | |
1865 | s->snapshots_offset = snapshots_offset; | |
1866 | s->snapshots_size = snapshots_size; | |
1867 | return 0; | |
1868 | fail: | |
1869 | return -1; | |
1870 | } | |
1871 | ||
1872 | static void find_new_snapshot_id(BlockDriverState *bs, | |
1873 | char *id_str, int id_str_size) | |
1874 | { | |
1875 | BDRVQcowState *s = bs->opaque; | |
1876 | QCowSnapshot *sn; | |
1877 | int i, id, id_max = 0; | |
1878 | ||
1879 | for(i = 0; i < s->nb_snapshots; i++) { | |
1880 | sn = s->snapshots + i; | |
1881 | id = strtoul(sn->id_str, NULL, 10); | |
1882 | if (id > id_max) | |
1883 | id_max = id; | |
1884 | } | |
1885 | snprintf(id_str, id_str_size, "%d", id_max + 1); | |
1886 | } | |
1887 | ||
1888 | static int find_snapshot_by_id(BlockDriverState *bs, const char *id_str) | |
1889 | { | |
1890 | BDRVQcowState *s = bs->opaque; | |
1891 | int i; | |
1892 | ||
1893 | for(i = 0; i < s->nb_snapshots; i++) { | |
1894 | if (!strcmp(s->snapshots[i].id_str, id_str)) | |
1895 | return i; | |
1896 | } | |
1897 | return -1; | |
1898 | } | |
1899 | ||
1900 | static int find_snapshot_by_id_or_name(BlockDriverState *bs, const char *name) | |
1901 | { | |
1902 | BDRVQcowState *s = bs->opaque; | |
1903 | int i, ret; | |
3b46e624 | 1904 | |
585f8587 FB |
1905 | ret = find_snapshot_by_id(bs, name); |
1906 | if (ret >= 0) | |
1907 | return ret; | |
1908 | for(i = 0; i < s->nb_snapshots; i++) { | |
1909 | if (!strcmp(s->snapshots[i].name, name)) | |
1910 | return i; | |
1911 | } | |
1912 | return -1; | |
1913 | } | |
1914 | ||
1915 | /* if no id is provided, a new one is constructed */ | |
5fafdf24 | 1916 | static int qcow_snapshot_create(BlockDriverState *bs, |
585f8587 FB |
1917 | QEMUSnapshotInfo *sn_info) |
1918 | { | |
1919 | BDRVQcowState *s = bs->opaque; | |
1920 | QCowSnapshot *snapshots1, sn1, *sn = &sn1; | |
1921 | int i, ret; | |
1922 | uint64_t *l1_table = NULL; | |
3b46e624 | 1923 | |
585f8587 FB |
1924 | memset(sn, 0, sizeof(*sn)); |
1925 | ||
1926 | if (sn_info->id_str[0] == '\0') { | |
1927 | /* compute a new id */ | |
1928 | find_new_snapshot_id(bs, sn_info->id_str, sizeof(sn_info->id_str)); | |
1929 | } | |
1930 | ||
1931 | /* check that the ID is unique */ | |
1932 | if (find_snapshot_by_id(bs, sn_info->id_str) >= 0) | |
1933 | return -ENOENT; | |
1934 | ||
1935 | sn->id_str = qemu_strdup(sn_info->id_str); | |
1936 | if (!sn->id_str) | |
1937 | goto fail; | |
1938 | sn->name = qemu_strdup(sn_info->name); | |
1939 | if (!sn->name) | |
1940 | goto fail; | |
1941 | sn->vm_state_size = sn_info->vm_state_size; | |
1942 | sn->date_sec = sn_info->date_sec; | |
1943 | sn->date_nsec = sn_info->date_nsec; | |
1944 | sn->vm_clock_nsec = sn_info->vm_clock_nsec; | |
1945 | ||
1946 | ret = update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 1); | |
1947 | if (ret < 0) | |
1948 | goto fail; | |
1949 | ||
1950 | /* create the L1 table of the snapshot */ | |
1951 | sn->l1_table_offset = alloc_clusters(bs, s->l1_size * sizeof(uint64_t)); | |
1952 | sn->l1_size = s->l1_size; | |
1953 | ||
1954 | l1_table = qemu_malloc(s->l1_size * sizeof(uint64_t)); | |
1955 | if (!l1_table) | |
1956 | goto fail; | |
1957 | for(i = 0; i < s->l1_size; i++) { | |
1958 | l1_table[i] = cpu_to_be64(s->l1_table[i]); | |
1959 | } | |
1960 | if (bdrv_pwrite(s->hd, sn->l1_table_offset, | |
5fafdf24 | 1961 | l1_table, s->l1_size * sizeof(uint64_t)) != |
585f8587 FB |
1962 | (s->l1_size * sizeof(uint64_t))) |
1963 | goto fail; | |
1964 | qemu_free(l1_table); | |
1965 | l1_table = NULL; | |
1966 | ||
1967 | snapshots1 = qemu_malloc((s->nb_snapshots + 1) * sizeof(QCowSnapshot)); | |
1968 | if (!snapshots1) | |
1969 | goto fail; | |
1970 | memcpy(snapshots1, s->snapshots, s->nb_snapshots * sizeof(QCowSnapshot)); | |
1971 | s->snapshots = snapshots1; | |
1972 | s->snapshots[s->nb_snapshots++] = *sn; | |
1973 | ||
1974 | if (qcow_write_snapshots(bs) < 0) | |
1975 | goto fail; | |
1976 | #ifdef DEBUG_ALLOC | |
1977 | check_refcounts(bs); | |
1978 | #endif | |
1979 | return 0; | |
1980 | fail: | |
1981 | qemu_free(sn->name); | |
1982 | qemu_free(l1_table); | |
1983 | return -1; | |
1984 | } | |
1985 | ||
1986 | /* copy the snapshot 'snapshot_name' into the current disk image */ | |
5fafdf24 | 1987 | static int qcow_snapshot_goto(BlockDriverState *bs, |
585f8587 FB |
1988 | const char *snapshot_id) |
1989 | { | |
1990 | BDRVQcowState *s = bs->opaque; | |
1991 | QCowSnapshot *sn; | |
1992 | int i, snapshot_index, l1_size2; | |
1993 | ||
1994 | snapshot_index = find_snapshot_by_id_or_name(bs, snapshot_id); | |
1995 | if (snapshot_index < 0) | |
1996 | return -ENOENT; | |
1997 | sn = &s->snapshots[snapshot_index]; | |
1998 | ||
1999 | if (update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, -1) < 0) | |
2000 | goto fail; | |
2001 | ||
2002 | if (grow_l1_table(bs, sn->l1_size) < 0) | |
2003 | goto fail; | |
2004 | ||
2005 | s->l1_size = sn->l1_size; | |
2006 | l1_size2 = s->l1_size * sizeof(uint64_t); | |
2007 | /* copy the snapshot l1 table to the current l1 table */ | |
5fafdf24 | 2008 | if (bdrv_pread(s->hd, sn->l1_table_offset, |
585f8587 FB |
2009 | s->l1_table, l1_size2) != l1_size2) |
2010 | goto fail; | |
2011 | if (bdrv_pwrite(s->hd, s->l1_table_offset, | |
2012 | s->l1_table, l1_size2) != l1_size2) | |
2013 | goto fail; | |
2014 | for(i = 0;i < s->l1_size; i++) { | |
2015 | be64_to_cpus(&s->l1_table[i]); | |
2016 | } | |
2017 | ||
2018 | if (update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 1) < 0) | |
2019 | goto fail; | |
2020 | ||
2021 | #ifdef DEBUG_ALLOC | |
2022 | check_refcounts(bs); | |
2023 | #endif | |
2024 | return 0; | |
2025 | fail: | |
2026 | return -EIO; | |
2027 | } | |
2028 | ||
2029 | static int qcow_snapshot_delete(BlockDriverState *bs, const char *snapshot_id) | |
2030 | { | |
2031 | BDRVQcowState *s = bs->opaque; | |
2032 | QCowSnapshot *sn; | |
2033 | int snapshot_index, ret; | |
3b46e624 | 2034 | |
585f8587 FB |
2035 | snapshot_index = find_snapshot_by_id_or_name(bs, snapshot_id); |
2036 | if (snapshot_index < 0) | |
2037 | return -ENOENT; | |
2038 | sn = &s->snapshots[snapshot_index]; | |
2039 | ||
2040 | ret = update_snapshot_refcount(bs, sn->l1_table_offset, sn->l1_size, -1); | |
2041 | if (ret < 0) | |
2042 | return ret; | |
2043 | /* must update the copied flag on the current cluster offsets */ | |
2044 | ret = update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 0); | |
2045 | if (ret < 0) | |
2046 | return ret; | |
2047 | free_clusters(bs, sn->l1_table_offset, sn->l1_size * sizeof(uint64_t)); | |
2048 | ||
2049 | qemu_free(sn->id_str); | |
2050 | qemu_free(sn->name); | |
2051 | memmove(sn, sn + 1, (s->nb_snapshots - snapshot_index - 1) * sizeof(*sn)); | |
2052 | s->nb_snapshots--; | |
2053 | ret = qcow_write_snapshots(bs); | |
2054 | if (ret < 0) { | |
2055 | /* XXX: restore snapshot if error ? */ | |
2056 | return ret; | |
2057 | } | |
2058 | #ifdef DEBUG_ALLOC | |
2059 | check_refcounts(bs); | |
2060 | #endif | |
2061 | return 0; | |
2062 | } | |
2063 | ||
5fafdf24 | 2064 | static int qcow_snapshot_list(BlockDriverState *bs, |
585f8587 FB |
2065 | QEMUSnapshotInfo **psn_tab) |
2066 | { | |
2067 | BDRVQcowState *s = bs->opaque; | |
2068 | QEMUSnapshotInfo *sn_tab, *sn_info; | |
2069 | QCowSnapshot *sn; | |
2070 | int i; | |
2071 | ||
2072 | sn_tab = qemu_mallocz(s->nb_snapshots * sizeof(QEMUSnapshotInfo)); | |
2073 | if (!sn_tab) | |
2074 | goto fail; | |
2075 | for(i = 0; i < s->nb_snapshots; i++) { | |
2076 | sn_info = sn_tab + i; | |
2077 | sn = s->snapshots + i; | |
2078 | pstrcpy(sn_info->id_str, sizeof(sn_info->id_str), | |
2079 | sn->id_str); | |
2080 | pstrcpy(sn_info->name, sizeof(sn_info->name), | |
2081 | sn->name); | |
2082 | sn_info->vm_state_size = sn->vm_state_size; | |
2083 | sn_info->date_sec = sn->date_sec; | |
2084 | sn_info->date_nsec = sn->date_nsec; | |
2085 | sn_info->vm_clock_nsec = sn->vm_clock_nsec; | |
2086 | } | |
2087 | *psn_tab = sn_tab; | |
2088 | return s->nb_snapshots; | |
2089 | fail: | |
2090 | qemu_free(sn_tab); | |
2091 | *psn_tab = NULL; | |
2092 | return -ENOMEM; | |
2093 | } | |
2094 | ||
2095 | /*********************************************************/ | |
2096 | /* refcount handling */ | |
2097 | ||
2098 | static int refcount_init(BlockDriverState *bs) | |
2099 | { | |
2100 | BDRVQcowState *s = bs->opaque; | |
2101 | int ret, refcount_table_size2, i; | |
3b46e624 | 2102 | |
585f8587 FB |
2103 | s->refcount_block_cache = qemu_malloc(s->cluster_size); |
2104 | if (!s->refcount_block_cache) | |
2105 | goto fail; | |
2106 | refcount_table_size2 = s->refcount_table_size * sizeof(uint64_t); | |
2107 | s->refcount_table = qemu_malloc(refcount_table_size2); | |
2108 | if (!s->refcount_table) | |
2109 | goto fail; | |
2110 | if (s->refcount_table_size > 0) { | |
2111 | ret = bdrv_pread(s->hd, s->refcount_table_offset, | |
2112 | s->refcount_table, refcount_table_size2); | |
2113 | if (ret != refcount_table_size2) | |
2114 | goto fail; | |
2115 | for(i = 0; i < s->refcount_table_size; i++) | |
2116 | be64_to_cpus(&s->refcount_table[i]); | |
2117 | } | |
2118 | return 0; | |
2119 | fail: | |
2120 | return -ENOMEM; | |
2121 | } | |
2122 | ||
2123 | static void refcount_close(BlockDriverState *bs) | |
2124 | { | |
2125 | BDRVQcowState *s = bs->opaque; | |
2126 | qemu_free(s->refcount_block_cache); | |
2127 | qemu_free(s->refcount_table); | |
2128 | } | |
2129 | ||
2130 | ||
5fafdf24 | 2131 | static int load_refcount_block(BlockDriverState *bs, |
585f8587 FB |
2132 | int64_t refcount_block_offset) |
2133 | { | |
2134 | BDRVQcowState *s = bs->opaque; | |
2135 | int ret; | |
5fafdf24 | 2136 | ret = bdrv_pread(s->hd, refcount_block_offset, s->refcount_block_cache, |
585f8587 FB |
2137 | s->cluster_size); |
2138 | if (ret != s->cluster_size) | |
2139 | return -EIO; | |
2140 | s->refcount_block_cache_offset = refcount_block_offset; | |
2141 | return 0; | |
2142 | } | |
2143 | ||
2144 | static int get_refcount(BlockDriverState *bs, int64_t cluster_index) | |
2145 | { | |
2146 | BDRVQcowState *s = bs->opaque; | |
2147 | int refcount_table_index, block_index; | |
2148 | int64_t refcount_block_offset; | |
2149 | ||
2150 | refcount_table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT); | |
2151 | if (refcount_table_index >= s->refcount_table_size) | |
2152 | return 0; | |
2153 | refcount_block_offset = s->refcount_table[refcount_table_index]; | |
2154 | if (!refcount_block_offset) | |
2155 | return 0; | |
2156 | if (refcount_block_offset != s->refcount_block_cache_offset) { | |
2157 | /* better than nothing: return allocated if read error */ | |
2158 | if (load_refcount_block(bs, refcount_block_offset) < 0) | |
2159 | return 1; | |
2160 | } | |
5fafdf24 | 2161 | block_index = cluster_index & |
585f8587 FB |
2162 | ((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1); |
2163 | return be16_to_cpu(s->refcount_block_cache[block_index]); | |
2164 | } | |
2165 | ||
2166 | /* return < 0 if error */ | |
2167 | static int64_t alloc_clusters_noref(BlockDriverState *bs, int64_t size) | |
2168 | { | |
2169 | BDRVQcowState *s = bs->opaque; | |
2170 | int i, nb_clusters; | |
2171 | ||
2172 | nb_clusters = (size + s->cluster_size - 1) >> s->cluster_bits; | |
2173 | for(;;) { | |
2174 | if (get_refcount(bs, s->free_cluster_index) == 0) { | |
2175 | s->free_cluster_index++; | |
2176 | for(i = 1; i < nb_clusters; i++) { | |
2177 | if (get_refcount(bs, s->free_cluster_index) != 0) | |
2178 | goto not_found; | |
2179 | s->free_cluster_index++; | |
2180 | } | |
2181 | #ifdef DEBUG_ALLOC2 | |
2182 | printf("alloc_clusters: size=%lld -> %lld\n", | |
5fafdf24 | 2183 | size, |
585f8587 FB |
2184 | (s->free_cluster_index - nb_clusters) << s->cluster_bits); |
2185 | #endif | |
2186 | return (s->free_cluster_index - nb_clusters) << s->cluster_bits; | |
2187 | } else { | |
2188 | not_found: | |
2189 | s->free_cluster_index++; | |
2190 | } | |
2191 | } | |
2192 | } | |
2193 | ||
2194 | static int64_t alloc_clusters(BlockDriverState *bs, int64_t size) | |
2195 | { | |
2196 | int64_t offset; | |
2197 | ||
2198 | offset = alloc_clusters_noref(bs, size); | |
2199 | update_refcount(bs, offset, size, 1); | |
2200 | return offset; | |
2201 | } | |
2202 | ||
2203 | /* only used to allocate compressed sectors. We try to allocate | |
2204 | contiguous sectors. size must be <= cluster_size */ | |
2205 | static int64_t alloc_bytes(BlockDriverState *bs, int size) | |
2206 | { | |
2207 | BDRVQcowState *s = bs->opaque; | |
2208 | int64_t offset, cluster_offset; | |
2209 | int free_in_cluster; | |
3b46e624 | 2210 | |
585f8587 FB |
2211 | assert(size > 0 && size <= s->cluster_size); |
2212 | if (s->free_byte_offset == 0) { | |
2213 | s->free_byte_offset = alloc_clusters(bs, s->cluster_size); | |
2214 | } | |
2215 | redo: | |
5fafdf24 | 2216 | free_in_cluster = s->cluster_size - |
585f8587 FB |
2217 | (s->free_byte_offset & (s->cluster_size - 1)); |
2218 | if (size <= free_in_cluster) { | |
2219 | /* enough space in current cluster */ | |
2220 | offset = s->free_byte_offset; | |
2221 | s->free_byte_offset += size; | |
2222 | free_in_cluster -= size; | |
2223 | if (free_in_cluster == 0) | |
2224 | s->free_byte_offset = 0; | |
2225 | if ((offset & (s->cluster_size - 1)) != 0) | |
2226 | update_cluster_refcount(bs, offset >> s->cluster_bits, 1); | |
2227 | } else { | |
2228 | offset = alloc_clusters(bs, s->cluster_size); | |
2229 | cluster_offset = s->free_byte_offset & ~(s->cluster_size - 1); | |
2230 | if ((cluster_offset + s->cluster_size) == offset) { | |
2231 | /* we are lucky: contiguous data */ | |
2232 | offset = s->free_byte_offset; | |
2233 | update_cluster_refcount(bs, offset >> s->cluster_bits, 1); | |
2234 | s->free_byte_offset += size; | |
2235 | } else { | |
2236 | s->free_byte_offset = offset; | |
2237 | goto redo; | |
2238 | } | |
2239 | } | |
2240 | return offset; | |
2241 | } | |
2242 | ||
5fafdf24 | 2243 | static void free_clusters(BlockDriverState *bs, |
585f8587 FB |
2244 | int64_t offset, int64_t size) |
2245 | { | |
2246 | update_refcount(bs, offset, size, -1); | |
2247 | } | |
2248 | ||
2249 | static int grow_refcount_table(BlockDriverState *bs, int min_size) | |
2250 | { | |
2251 | BDRVQcowState *s = bs->opaque; | |
2252 | int new_table_size, new_table_size2, refcount_table_clusters, i, ret; | |
2253 | uint64_t *new_table; | |
2254 | int64_t table_offset; | |
2255 | uint64_t data64; | |
2256 | uint32_t data32; | |
23be50f1 TS |
2257 | int old_table_size; |
2258 | int64_t old_table_offset; | |
585f8587 FB |
2259 | |
2260 | if (min_size <= s->refcount_table_size) | |
2261 | return 0; | |
2262 | /* compute new table size */ | |
2263 | refcount_table_clusters = s->refcount_table_size >> (s->cluster_bits - 3); | |
2264 | for(;;) { | |
2265 | if (refcount_table_clusters == 0) { | |
2266 | refcount_table_clusters = 1; | |
2267 | } else { | |
2268 | refcount_table_clusters = (refcount_table_clusters * 3 + 1) / 2; | |
2269 | } | |
2270 | new_table_size = refcount_table_clusters << (s->cluster_bits - 3); | |
2271 | if (min_size <= new_table_size) | |
2272 | break; | |
2273 | } | |
15e6690a FB |
2274 | #ifdef DEBUG_ALLOC2 |
2275 | printf("grow_refcount_table from %d to %d\n", | |
2276 | s->refcount_table_size, | |
2277 | new_table_size); | |
2278 | #endif | |
585f8587 FB |
2279 | new_table_size2 = new_table_size * sizeof(uint64_t); |
2280 | new_table = qemu_mallocz(new_table_size2); | |
2281 | if (!new_table) | |
2282 | return -ENOMEM; | |
5fafdf24 | 2283 | memcpy(new_table, s->refcount_table, |
585f8587 FB |
2284 | s->refcount_table_size * sizeof(uint64_t)); |
2285 | for(i = 0; i < s->refcount_table_size; i++) | |
2286 | cpu_to_be64s(&new_table[i]); | |
2287 | /* Note: we cannot update the refcount now to avoid recursion */ | |
2288 | table_offset = alloc_clusters_noref(bs, new_table_size2); | |
2289 | ret = bdrv_pwrite(s->hd, table_offset, new_table, new_table_size2); | |
5fafdf24 | 2290 | if (ret != new_table_size2) |
585f8587 FB |
2291 | goto fail; |
2292 | for(i = 0; i < s->refcount_table_size; i++) | |
2293 | be64_to_cpus(&new_table[i]); | |
2294 | ||
2295 | data64 = cpu_to_be64(table_offset); | |
2296 | if (bdrv_pwrite(s->hd, offsetof(QCowHeader, refcount_table_offset), | |
2297 | &data64, sizeof(data64)) != sizeof(data64)) | |
2298 | goto fail; | |
2299 | data32 = cpu_to_be32(refcount_table_clusters); | |
2300 | if (bdrv_pwrite(s->hd, offsetof(QCowHeader, refcount_table_clusters), | |
2301 | &data32, sizeof(data32)) != sizeof(data32)) | |
2302 | goto fail; | |
2303 | qemu_free(s->refcount_table); | |
23be50f1 TS |
2304 | old_table_offset = s->refcount_table_offset; |
2305 | old_table_size = s->refcount_table_size; | |
585f8587 FB |
2306 | s->refcount_table = new_table; |
2307 | s->refcount_table_size = new_table_size; | |
a4080ece | 2308 | s->refcount_table_offset = table_offset; |
585f8587 FB |
2309 | |
2310 | update_refcount(bs, table_offset, new_table_size2, 1); | |
23be50f1 | 2311 | free_clusters(bs, old_table_offset, old_table_size * sizeof(uint64_t)); |
585f8587 FB |
2312 | return 0; |
2313 | fail: | |
2314 | free_clusters(bs, table_offset, new_table_size2); | |
2315 | qemu_free(new_table); | |
2316 | return -EIO; | |
2317 | } | |
2318 | ||
2319 | /* addend must be 1 or -1 */ | |
2320 | /* XXX: cache several refcount block clusters ? */ | |
5fafdf24 | 2321 | static int update_cluster_refcount(BlockDriverState *bs, |
585f8587 FB |
2322 | int64_t cluster_index, |
2323 | int addend) | |
2324 | { | |
2325 | BDRVQcowState *s = bs->opaque; | |
2326 | int64_t offset, refcount_block_offset; | |
2327 | int ret, refcount_table_index, block_index, refcount; | |
2328 | uint64_t data64; | |
2329 | ||
2330 | refcount_table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT); | |
2331 | if (refcount_table_index >= s->refcount_table_size) { | |
2332 | if (addend < 0) | |
2333 | return -EINVAL; | |
2334 | ret = grow_refcount_table(bs, refcount_table_index + 1); | |
2335 | if (ret < 0) | |
2336 | return ret; | |
2337 | } | |
2338 | refcount_block_offset = s->refcount_table[refcount_table_index]; | |
2339 | if (!refcount_block_offset) { | |
2340 | if (addend < 0) | |
2341 | return -EINVAL; | |
2342 | /* create a new refcount block */ | |
2343 | /* Note: we cannot update the refcount now to avoid recursion */ | |
2344 | offset = alloc_clusters_noref(bs, s->cluster_size); | |
2345 | memset(s->refcount_block_cache, 0, s->cluster_size); | |
2346 | ret = bdrv_pwrite(s->hd, offset, s->refcount_block_cache, s->cluster_size); | |
2347 | if (ret != s->cluster_size) | |
2348 | return -EINVAL; | |
2349 | s->refcount_table[refcount_table_index] = offset; | |
2350 | data64 = cpu_to_be64(offset); | |
5fafdf24 TS |
2351 | ret = bdrv_pwrite(s->hd, s->refcount_table_offset + |
2352 | refcount_table_index * sizeof(uint64_t), | |
585f8587 FB |
2353 | &data64, sizeof(data64)); |
2354 | if (ret != sizeof(data64)) | |
2355 | return -EINVAL; | |
2356 | ||
2357 | refcount_block_offset = offset; | |
2358 | s->refcount_block_cache_offset = offset; | |
2359 | update_refcount(bs, offset, s->cluster_size, 1); | |
2360 | } else { | |
2361 | if (refcount_block_offset != s->refcount_block_cache_offset) { | |
2362 | if (load_refcount_block(bs, refcount_block_offset) < 0) | |
2363 | return -EIO; | |
2364 | } | |
2365 | } | |
2366 | /* we can update the count and save it */ | |
5fafdf24 | 2367 | block_index = cluster_index & |
585f8587 FB |
2368 | ((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1); |
2369 | refcount = be16_to_cpu(s->refcount_block_cache[block_index]); | |
2370 | refcount += addend; | |
2371 | if (refcount < 0 || refcount > 0xffff) | |
2372 | return -EINVAL; | |
2373 | if (refcount == 0 && cluster_index < s->free_cluster_index) { | |
2374 | s->free_cluster_index = cluster_index; | |
2375 | } | |
2376 | s->refcount_block_cache[block_index] = cpu_to_be16(refcount); | |
5fafdf24 TS |
2377 | if (bdrv_pwrite(s->hd, |
2378 | refcount_block_offset + (block_index << REFCOUNT_SHIFT), | |
585f8587 FB |
2379 | &s->refcount_block_cache[block_index], 2) != 2) |
2380 | return -EIO; | |
2381 | return refcount; | |
2382 | } | |
2383 | ||
5fafdf24 TS |
2384 | static void update_refcount(BlockDriverState *bs, |
2385 | int64_t offset, int64_t length, | |
585f8587 FB |
2386 | int addend) |
2387 | { | |
2388 | BDRVQcowState *s = bs->opaque; | |
2389 | int64_t start, last, cluster_offset; | |
2390 | ||
2391 | #ifdef DEBUG_ALLOC2 | |
5fafdf24 | 2392 | printf("update_refcount: offset=%lld size=%lld addend=%d\n", |
585f8587 FB |
2393 | offset, length, addend); |
2394 | #endif | |
2395 | if (length <= 0) | |
2396 | return; | |
2397 | start = offset & ~(s->cluster_size - 1); | |
2398 | last = (offset + length - 1) & ~(s->cluster_size - 1); | |
5fafdf24 | 2399 | for(cluster_offset = start; cluster_offset <= last; |
585f8587 FB |
2400 | cluster_offset += s->cluster_size) { |
2401 | update_cluster_refcount(bs, cluster_offset >> s->cluster_bits, addend); | |
2402 | } | |
2403 | } | |
2404 | ||
2405 | #ifdef DEBUG_ALLOC | |
5fafdf24 TS |
2406 | static void inc_refcounts(BlockDriverState *bs, |
2407 | uint16_t *refcount_table, | |
585f8587 FB |
2408 | int refcount_table_size, |
2409 | int64_t offset, int64_t size) | |
2410 | { | |
2411 | BDRVQcowState *s = bs->opaque; | |
2412 | int64_t start, last, cluster_offset; | |
2413 | int k; | |
3b46e624 | 2414 | |
585f8587 FB |
2415 | if (size <= 0) |
2416 | return; | |
2417 | ||
2418 | start = offset & ~(s->cluster_size - 1); | |
2419 | last = (offset + size - 1) & ~(s->cluster_size - 1); | |
5fafdf24 | 2420 | for(cluster_offset = start; cluster_offset <= last; |
585f8587 FB |
2421 | cluster_offset += s->cluster_size) { |
2422 | k = cluster_offset >> s->cluster_bits; | |
2423 | if (k < 0 || k >= refcount_table_size) { | |
2424 | printf("ERROR: invalid cluster offset=0x%llx\n", cluster_offset); | |
2425 | } else { | |
2426 | if (++refcount_table[k] == 0) { | |
2427 | printf("ERROR: overflow cluster offset=0x%llx\n", cluster_offset); | |
2428 | } | |
2429 | } | |
2430 | } | |
2431 | } | |
2432 | ||
5fafdf24 TS |
2433 | static int check_refcounts_l1(BlockDriverState *bs, |
2434 | uint16_t *refcount_table, | |
585f8587 FB |
2435 | int refcount_table_size, |
2436 | int64_t l1_table_offset, int l1_size, | |
2437 | int check_copied) | |
2438 | { | |
2439 | BDRVQcowState *s = bs->opaque; | |
2440 | uint64_t *l1_table, *l2_table, l2_offset, offset, l1_size2; | |
2441 | int l2_size, i, j, nb_csectors, refcount; | |
2442 | ||
2443 | l2_table = NULL; | |
2444 | l1_size2 = l1_size * sizeof(uint64_t); | |
2445 | ||
2446 | inc_refcounts(bs, refcount_table, refcount_table_size, | |
2447 | l1_table_offset, l1_size2); | |
2448 | ||
2449 | l1_table = qemu_malloc(l1_size2); | |
2450 | if (!l1_table) | |
2451 | goto fail; | |
5fafdf24 | 2452 | if (bdrv_pread(s->hd, l1_table_offset, |
585f8587 FB |
2453 | l1_table, l1_size2) != l1_size2) |
2454 | goto fail; | |
2455 | for(i = 0;i < l1_size; i++) | |
2456 | be64_to_cpus(&l1_table[i]); | |
3b46e624 | 2457 | |
585f8587 FB |
2458 | l2_size = s->l2_size * sizeof(uint64_t); |
2459 | l2_table = qemu_malloc(l2_size); | |
2460 | if (!l2_table) | |
2461 | goto fail; | |
2462 | for(i = 0; i < l1_size; i++) { | |
2463 | l2_offset = l1_table[i]; | |
2464 | if (l2_offset) { | |
2465 | if (check_copied) { | |
2466 | refcount = get_refcount(bs, (l2_offset & ~QCOW_OFLAG_COPIED) >> s->cluster_bits); | |
2467 | if ((refcount == 1) != ((l2_offset & QCOW_OFLAG_COPIED) != 0)) { | |
2468 | printf("ERROR OFLAG_COPIED: l2_offset=%llx refcount=%d\n", | |
2469 | l2_offset, refcount); | |
2470 | } | |
2471 | } | |
2472 | l2_offset &= ~QCOW_OFLAG_COPIED; | |
2473 | if (bdrv_pread(s->hd, l2_offset, l2_table, l2_size) != l2_size) | |
2474 | goto fail; | |
2475 | for(j = 0; j < s->l2_size; j++) { | |
2476 | offset = be64_to_cpu(l2_table[j]); | |
2477 | if (offset != 0) { | |
2478 | if (offset & QCOW_OFLAG_COMPRESSED) { | |
2479 | if (offset & QCOW_OFLAG_COPIED) { | |
2480 | printf("ERROR: cluster %lld: copied flag must never be set for compressed clusters\n", | |
2481 | offset >> s->cluster_bits); | |
2482 | offset &= ~QCOW_OFLAG_COPIED; | |
2483 | } | |
5fafdf24 | 2484 | nb_csectors = ((offset >> s->csize_shift) & |
585f8587 FB |
2485 | s->csize_mask) + 1; |
2486 | offset &= s->cluster_offset_mask; | |
5fafdf24 | 2487 | inc_refcounts(bs, refcount_table, |
585f8587 FB |
2488 | refcount_table_size, |
2489 | offset & ~511, nb_csectors * 512); | |
2490 | } else { | |
2491 | if (check_copied) { | |
2492 | refcount = get_refcount(bs, (offset & ~QCOW_OFLAG_COPIED) >> s->cluster_bits); | |
2493 | if ((refcount == 1) != ((offset & QCOW_OFLAG_COPIED) != 0)) { | |
2494 | printf("ERROR OFLAG_COPIED: offset=%llx refcount=%d\n", | |
2495 | offset, refcount); | |
2496 | } | |
2497 | } | |
2498 | offset &= ~QCOW_OFLAG_COPIED; | |
5fafdf24 | 2499 | inc_refcounts(bs, refcount_table, |
585f8587 FB |
2500 | refcount_table_size, |
2501 | offset, s->cluster_size); | |
2502 | } | |
2503 | } | |
2504 | } | |
5fafdf24 | 2505 | inc_refcounts(bs, refcount_table, |
585f8587 FB |
2506 | refcount_table_size, |
2507 | l2_offset, | |
2508 | s->cluster_size); | |
2509 | } | |
2510 | } | |
2511 | qemu_free(l1_table); | |
2512 | qemu_free(l2_table); | |
2513 | return 0; | |
2514 | fail: | |
2515 | printf("ERROR: I/O error in check_refcounts_l1\n"); | |
2516 | qemu_free(l1_table); | |
2517 | qemu_free(l2_table); | |
2518 | return -EIO; | |
2519 | } | |
2520 | ||
2521 | static void check_refcounts(BlockDriverState *bs) | |
2522 | { | |
2523 | BDRVQcowState *s = bs->opaque; | |
2524 | int64_t size; | |
2525 | int nb_clusters, refcount1, refcount2, i; | |
2526 | QCowSnapshot *sn; | |
2527 | uint16_t *refcount_table; | |
2528 | ||
2529 | size = bdrv_getlength(s->hd); | |
2530 | nb_clusters = (size + s->cluster_size - 1) >> s->cluster_bits; | |
2531 | refcount_table = qemu_mallocz(nb_clusters * sizeof(uint16_t)); | |
15e6690a | 2532 | |
585f8587 FB |
2533 | /* header */ |
2534 | inc_refcounts(bs, refcount_table, nb_clusters, | |
2535 | 0, s->cluster_size); | |
3b46e624 | 2536 | |
585f8587 FB |
2537 | check_refcounts_l1(bs, refcount_table, nb_clusters, |
2538 | s->l1_table_offset, s->l1_size, 1); | |
2539 | ||
2540 | /* snapshots */ | |
2541 | for(i = 0; i < s->nb_snapshots; i++) { | |
2542 | sn = s->snapshots + i; | |
2543 | check_refcounts_l1(bs, refcount_table, nb_clusters, | |
2544 | sn->l1_table_offset, sn->l1_size, 0); | |
2545 | } | |
2546 | inc_refcounts(bs, refcount_table, nb_clusters, | |
2547 | s->snapshots_offset, s->snapshots_size); | |
2548 | ||
2549 | /* refcount data */ | |
2550 | inc_refcounts(bs, refcount_table, nb_clusters, | |
5fafdf24 | 2551 | s->refcount_table_offset, |
585f8587 FB |
2552 | s->refcount_table_size * sizeof(uint64_t)); |
2553 | for(i = 0; i < s->refcount_table_size; i++) { | |
2554 | int64_t offset; | |
2555 | offset = s->refcount_table[i]; | |
2556 | if (offset != 0) { | |
2557 | inc_refcounts(bs, refcount_table, nb_clusters, | |
2558 | offset, s->cluster_size); | |
2559 | } | |
2560 | } | |
2561 | ||
2562 | /* compare ref counts */ | |
2563 | for(i = 0; i < nb_clusters; i++) { | |
2564 | refcount1 = get_refcount(bs, i); | |
2565 | refcount2 = refcount_table[i]; | |
2566 | if (refcount1 != refcount2) | |
2567 | printf("ERROR cluster %d refcount=%d reference=%d\n", | |
2568 | i, refcount1, refcount2); | |
2569 | } | |
2570 | ||
2571 | qemu_free(refcount_table); | |
2572 | } | |
2573 | ||
2574 | #if 0 | |
2575 | static void dump_refcounts(BlockDriverState *bs) | |
2576 | { | |
2577 | BDRVQcowState *s = bs->opaque; | |
2578 | int64_t nb_clusters, k, k1, size; | |
2579 | int refcount; | |
2580 | ||
2581 | size = bdrv_getlength(s->hd); | |
2582 | nb_clusters = (size + s->cluster_size - 1) >> s->cluster_bits; | |
2583 | for(k = 0; k < nb_clusters;) { | |
2584 | k1 = k; | |
2585 | refcount = get_refcount(bs, k); | |
2586 | k++; | |
2587 | while (k < nb_clusters && get_refcount(bs, k) == refcount) | |
2588 | k++; | |
2589 | printf("%lld: refcount=%d nb=%lld\n", k, refcount, k - k1); | |
2590 | } | |
2591 | } | |
2592 | #endif | |
2593 | #endif | |
2594 | ||
2595 | BlockDriver bdrv_qcow2 = { | |
2596 | "qcow2", | |
2597 | sizeof(BDRVQcowState), | |
2598 | qcow_probe, | |
2599 | qcow_open, | |
2600 | NULL, | |
2601 | NULL, | |
2602 | qcow_close, | |
2603 | qcow_create, | |
2604 | qcow_flush, | |
2605 | qcow_is_allocated, | |
2606 | qcow_set_key, | |
2607 | qcow_make_empty, | |
2608 | ||
585f8587 FB |
2609 | .bdrv_aio_read = qcow_aio_read, |
2610 | .bdrv_aio_write = qcow_aio_write, | |
2611 | .bdrv_aio_cancel = qcow_aio_cancel, | |
ce1a14dc | 2612 | .aiocb_size = sizeof(QCowAIOCB), |
585f8587 FB |
2613 | .bdrv_write_compressed = qcow_write_compressed, |
2614 | ||
2615 | .bdrv_snapshot_create = qcow_snapshot_create, | |
2616 | .bdrv_snapshot_goto = qcow_snapshot_goto, | |
2617 | .bdrv_snapshot_delete = qcow_snapshot_delete, | |
2618 | .bdrv_snapshot_list = qcow_snapshot_list, | |
2619 | .bdrv_get_info = qcow_get_info, | |
2620 | }; |