]>
Commit | Line | Data |
---|---|---|
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 | |
9b80ddf3 | 48 | //#define DEBUG_EXT |
5fafdf24 | 49 | |
585f8587 FB |
50 | #define QCOW_MAGIC (('Q' << 24) | ('F' << 16) | ('I' << 8) | 0xfb) |
51 | #define QCOW_VERSION 2 | |
52 | ||
53 | #define QCOW_CRYPT_NONE 0 | |
54 | #define QCOW_CRYPT_AES 1 | |
55 | ||
095a9c58 AL |
56 | #define QCOW_MAX_CRYPT_CLUSTERS 32 |
57 | ||
585f8587 FB |
58 | /* indicate that the refcount of the referenced cluster is exactly one. */ |
59 | #define QCOW_OFLAG_COPIED (1LL << 63) | |
60 | /* indicate that the cluster is compressed (they never have the copied flag) */ | |
61 | #define QCOW_OFLAG_COMPRESSED (1LL << 62) | |
62 | ||
63 | #define REFCOUNT_SHIFT 1 /* refcount size is 2 bytes */ | |
64 | ||
585f8587 FB |
65 | typedef struct QCowHeader { |
66 | uint32_t magic; | |
67 | uint32_t version; | |
68 | uint64_t backing_file_offset; | |
69 | uint32_t backing_file_size; | |
70 | uint32_t cluster_bits; | |
71 | uint64_t size; /* in bytes */ | |
72 | uint32_t crypt_method; | |
73 | uint32_t l1_size; /* XXX: save number of clusters instead ? */ | |
74 | uint64_t l1_table_offset; | |
75 | uint64_t refcount_table_offset; | |
76 | uint32_t refcount_table_clusters; | |
77 | uint32_t nb_snapshots; | |
78 | uint64_t snapshots_offset; | |
79 | } QCowHeader; | |
80 | ||
9b80ddf3 AL |
81 | |
82 | typedef struct { | |
83 | uint32_t magic; | |
84 | uint32_t len; | |
85 | } QCowExtension; | |
86 | #define QCOW_EXT_MAGIC_END 0 | |
f965509c | 87 | #define QCOW_EXT_MAGIC_BACKING_FORMAT 0xE2792ACA |
9b80ddf3 AL |
88 | |
89 | ||
585f8587 FB |
90 | typedef struct __attribute__((packed)) QCowSnapshotHeader { |
91 | /* header is 8 byte aligned */ | |
92 | uint64_t l1_table_offset; | |
93 | ||
94 | uint32_t l1_size; | |
95 | uint16_t id_str_size; | |
96 | uint16_t name_size; | |
97 | ||
98 | uint32_t date_sec; | |
99 | uint32_t date_nsec; | |
100 | ||
101 | uint64_t vm_clock_nsec; | |
102 | ||
103 | uint32_t vm_state_size; | |
104 | uint32_t extra_data_size; /* for extension */ | |
105 | /* extra data follows */ | |
106 | /* id_str follows */ | |
107 | /* name follows */ | |
108 | } QCowSnapshotHeader; | |
109 | ||
110 | #define L2_CACHE_SIZE 16 | |
111 | ||
112 | typedef struct QCowSnapshot { | |
113 | uint64_t l1_table_offset; | |
114 | uint32_t l1_size; | |
115 | char *id_str; | |
116 | char *name; | |
117 | uint32_t vm_state_size; | |
118 | uint32_t date_sec; | |
119 | uint32_t date_nsec; | |
120 | uint64_t vm_clock_nsec; | |
121 | } QCowSnapshot; | |
122 | ||
123 | typedef struct BDRVQcowState { | |
124 | BlockDriverState *hd; | |
125 | int cluster_bits; | |
126 | int cluster_size; | |
127 | int cluster_sectors; | |
128 | int l2_bits; | |
129 | int l2_size; | |
130 | int l1_size; | |
131 | int l1_vm_state_index; | |
132 | int csize_shift; | |
133 | int csize_mask; | |
134 | uint64_t cluster_offset_mask; | |
135 | uint64_t l1_table_offset; | |
136 | uint64_t *l1_table; | |
137 | uint64_t *l2_cache; | |
138 | uint64_t l2_cache_offsets[L2_CACHE_SIZE]; | |
139 | uint32_t l2_cache_counts[L2_CACHE_SIZE]; | |
140 | uint8_t *cluster_cache; | |
141 | uint8_t *cluster_data; | |
142 | uint64_t cluster_cache_offset; | |
143 | ||
144 | uint64_t *refcount_table; | |
145 | uint64_t refcount_table_offset; | |
146 | uint32_t refcount_table_size; | |
147 | uint64_t refcount_block_cache_offset; | |
148 | uint16_t *refcount_block_cache; | |
149 | int64_t free_cluster_index; | |
150 | int64_t free_byte_offset; | |
151 | ||
152 | uint32_t crypt_method; /* current crypt method, 0 if no key yet */ | |
153 | uint32_t crypt_method_header; | |
154 | AES_KEY aes_encrypt_key; | |
155 | AES_KEY aes_decrypt_key; | |
156 | uint64_t snapshots_offset; | |
157 | int snapshots_size; | |
158 | int nb_snapshots; | |
159 | QCowSnapshot *snapshots; | |
160 | } BDRVQcowState; | |
161 | ||
162 | static int decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset); | |
5fafdf24 | 163 | static int qcow_read(BlockDriverState *bs, int64_t sector_num, |
585f8587 FB |
164 | uint8_t *buf, int nb_sectors); |
165 | static int qcow_read_snapshots(BlockDriverState *bs); | |
166 | static void qcow_free_snapshots(BlockDriverState *bs); | |
167 | static int refcount_init(BlockDriverState *bs); | |
168 | static void refcount_close(BlockDriverState *bs); | |
169 | static int get_refcount(BlockDriverState *bs, int64_t cluster_index); | |
5fafdf24 | 170 | static int update_cluster_refcount(BlockDriverState *bs, |
585f8587 FB |
171 | int64_t cluster_index, |
172 | int addend); | |
5fafdf24 TS |
173 | static void update_refcount(BlockDriverState *bs, |
174 | int64_t offset, int64_t length, | |
585f8587 FB |
175 | int addend); |
176 | static int64_t alloc_clusters(BlockDriverState *bs, int64_t size); | |
177 | static int64_t alloc_bytes(BlockDriverState *bs, int size); | |
5fafdf24 | 178 | static void free_clusters(BlockDriverState *bs, |
585f8587 | 179 | int64_t offset, int64_t size); |
e97fc193 | 180 | static int check_refcounts(BlockDriverState *bs); |
585f8587 FB |
181 | |
182 | static int qcow_probe(const uint8_t *buf, int buf_size, const char *filename) | |
183 | { | |
184 | const QCowHeader *cow_header = (const void *)buf; | |
3b46e624 | 185 | |
585f8587 FB |
186 | if (buf_size >= sizeof(QCowHeader) && |
187 | be32_to_cpu(cow_header->magic) == QCOW_MAGIC && | |
5fafdf24 | 188 | be32_to_cpu(cow_header->version) == QCOW_VERSION) |
585f8587 FB |
189 | return 100; |
190 | else | |
191 | return 0; | |
192 | } | |
193 | ||
9b80ddf3 AL |
194 | |
195 | /* | |
196 | * read qcow2 extension and fill bs | |
197 | * start reading from start_offset | |
198 | * finish reading upon magic of value 0 or when end_offset reached | |
199 | * unknown magic is skipped (future extension this version knows nothing about) | |
200 | * return 0 upon success, non-0 otherwise | |
201 | */ | |
202 | static int qcow_read_extensions(BlockDriverState *bs, uint64_t start_offset, | |
203 | uint64_t end_offset) | |
204 | { | |
205 | BDRVQcowState *s = bs->opaque; | |
206 | QCowExtension ext; | |
207 | uint64_t offset; | |
208 | ||
209 | #ifdef DEBUG_EXT | |
210 | printf("qcow_read_extensions: start=%ld end=%ld\n", start_offset, end_offset); | |
211 | #endif | |
212 | offset = start_offset; | |
213 | while (offset < end_offset) { | |
214 | ||
215 | #ifdef DEBUG_EXT | |
216 | /* Sanity check */ | |
217 | if (offset > s->cluster_size) | |
218 | printf("qcow_handle_extension: suspicious offset %lu\n", offset); | |
219 | ||
220 | printf("attemting to read extended header in offset %lu\n", offset); | |
221 | #endif | |
222 | ||
223 | if (bdrv_pread(s->hd, offset, &ext, sizeof(ext)) != sizeof(ext)) { | |
4c978075 AL |
224 | fprintf(stderr, "qcow_handle_extension: ERROR: pread fail from offset %llu\n", |
225 | (unsigned long long)offset); | |
9b80ddf3 AL |
226 | return 1; |
227 | } | |
228 | be32_to_cpus(&ext.magic); | |
229 | be32_to_cpus(&ext.len); | |
230 | offset += sizeof(ext); | |
231 | #ifdef DEBUG_EXT | |
232 | printf("ext.magic = 0x%x\n", ext.magic); | |
233 | #endif | |
234 | switch (ext.magic) { | |
235 | case QCOW_EXT_MAGIC_END: | |
236 | return 0; | |
f965509c AL |
237 | |
238 | case QCOW_EXT_MAGIC_BACKING_FORMAT: | |
239 | if (ext.len >= sizeof(bs->backing_format)) { | |
240 | fprintf(stderr, "ERROR: ext_backing_format: len=%u too large" | |
4c978075 | 241 | " (>=%zu)\n", |
f965509c AL |
242 | ext.len, sizeof(bs->backing_format)); |
243 | return 2; | |
244 | } | |
245 | if (bdrv_pread(s->hd, offset , bs->backing_format, | |
246 | ext.len) != ext.len) | |
247 | return 3; | |
248 | bs->backing_format[ext.len] = '\0'; | |
249 | #ifdef DEBUG_EXT | |
250 | printf("Qcow2: Got format extension %s\n", bs->backing_format); | |
251 | #endif | |
252 | offset += ((ext.len + 7) & ~7); | |
253 | break; | |
254 | ||
9b80ddf3 AL |
255 | default: |
256 | /* unknown magic -- just skip it */ | |
257 | offset += ((ext.len + 7) & ~7); | |
258 | break; | |
259 | } | |
260 | } | |
261 | ||
262 | return 0; | |
263 | } | |
264 | ||
265 | ||
585f8587 FB |
266 | static int qcow_open(BlockDriverState *bs, const char *filename, int flags) |
267 | { | |
268 | BDRVQcowState *s = bs->opaque; | |
269 | int len, i, shift, ret; | |
270 | QCowHeader header; | |
9b80ddf3 | 271 | uint64_t ext_end; |
585f8587 | 272 | |
4dc822d7 AL |
273 | /* Performance is terrible right now with cache=writethrough due mainly |
274 | * to reference count updates. If the user does not explicitly specify | |
275 | * a caching type, force to writeback caching. | |
276 | */ | |
277 | if ((flags & BDRV_O_CACHE_DEF)) { | |
278 | flags |= BDRV_O_CACHE_WB; | |
279 | flags &= ~BDRV_O_CACHE_DEF; | |
280 | } | |
b5eff355 | 281 | ret = bdrv_file_open(&s->hd, filename, flags); |
585f8587 FB |
282 | if (ret < 0) |
283 | return ret; | |
284 | if (bdrv_pread(s->hd, 0, &header, sizeof(header)) != sizeof(header)) | |
285 | goto fail; | |
286 | be32_to_cpus(&header.magic); | |
287 | be32_to_cpus(&header.version); | |
288 | be64_to_cpus(&header.backing_file_offset); | |
289 | be32_to_cpus(&header.backing_file_size); | |
290 | be64_to_cpus(&header.size); | |
291 | be32_to_cpus(&header.cluster_bits); | |
292 | be32_to_cpus(&header.crypt_method); | |
293 | be64_to_cpus(&header.l1_table_offset); | |
294 | be32_to_cpus(&header.l1_size); | |
295 | be64_to_cpus(&header.refcount_table_offset); | |
296 | be32_to_cpus(&header.refcount_table_clusters); | |
297 | be64_to_cpus(&header.snapshots_offset); | |
298 | be32_to_cpus(&header.nb_snapshots); | |
3b46e624 | 299 | |
585f8587 FB |
300 | if (header.magic != QCOW_MAGIC || header.version != QCOW_VERSION) |
301 | goto fail; | |
5fafdf24 TS |
302 | if (header.size <= 1 || |
303 | header.cluster_bits < 9 || | |
585f8587 FB |
304 | header.cluster_bits > 16) |
305 | goto fail; | |
306 | if (header.crypt_method > QCOW_CRYPT_AES) | |
307 | goto fail; | |
308 | s->crypt_method_header = header.crypt_method; | |
309 | if (s->crypt_method_header) | |
310 | bs->encrypted = 1; | |
311 | s->cluster_bits = header.cluster_bits; | |
312 | s->cluster_size = 1 << s->cluster_bits; | |
313 | s->cluster_sectors = 1 << (s->cluster_bits - 9); | |
314 | s->l2_bits = s->cluster_bits - 3; /* L2 is always one cluster */ | |
315 | s->l2_size = 1 << s->l2_bits; | |
316 | bs->total_sectors = header.size / 512; | |
317 | s->csize_shift = (62 - (s->cluster_bits - 8)); | |
318 | s->csize_mask = (1 << (s->cluster_bits - 8)) - 1; | |
319 | s->cluster_offset_mask = (1LL << s->csize_shift) - 1; | |
320 | s->refcount_table_offset = header.refcount_table_offset; | |
5fafdf24 | 321 | s->refcount_table_size = |
585f8587 FB |
322 | header.refcount_table_clusters << (s->cluster_bits - 3); |
323 | ||
324 | s->snapshots_offset = header.snapshots_offset; | |
325 | s->nb_snapshots = header.nb_snapshots; | |
326 | ||
327 | /* read the level 1 table */ | |
328 | s->l1_size = header.l1_size; | |
329 | shift = s->cluster_bits + s->l2_bits; | |
330 | s->l1_vm_state_index = (header.size + (1LL << shift) - 1) >> shift; | |
331 | /* the L1 table must contain at least enough entries to put | |
332 | header.size bytes */ | |
333 | if (s->l1_size < s->l1_vm_state_index) | |
334 | goto fail; | |
335 | s->l1_table_offset = header.l1_table_offset; | |
336 | s->l1_table = qemu_malloc(s->l1_size * sizeof(uint64_t)); | |
5fafdf24 | 337 | if (bdrv_pread(s->hd, s->l1_table_offset, s->l1_table, s->l1_size * sizeof(uint64_t)) != |
585f8587 FB |
338 | s->l1_size * sizeof(uint64_t)) |
339 | goto fail; | |
340 | for(i = 0;i < s->l1_size; i++) { | |
341 | be64_to_cpus(&s->l1_table[i]); | |
342 | } | |
343 | /* alloc L2 cache */ | |
344 | s->l2_cache = qemu_malloc(s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t)); | |
585f8587 | 345 | s->cluster_cache = qemu_malloc(s->cluster_size); |
585f8587 | 346 | /* one more sector for decompressed data alignment */ |
095a9c58 AL |
347 | s->cluster_data = qemu_malloc(QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size |
348 | + 512); | |
585f8587 | 349 | s->cluster_cache_offset = -1; |
3b46e624 | 350 | |
585f8587 FB |
351 | if (refcount_init(bs) < 0) |
352 | goto fail; | |
353 | ||
9b80ddf3 AL |
354 | /* read qcow2 extensions */ |
355 | if (header.backing_file_offset) | |
356 | ext_end = header.backing_file_offset; | |
357 | else | |
358 | ext_end = s->cluster_size; | |
359 | if (qcow_read_extensions(bs, sizeof(header), ext_end)) | |
360 | goto fail; | |
361 | ||
585f8587 FB |
362 | /* read the backing file name */ |
363 | if (header.backing_file_offset != 0) { | |
364 | len = header.backing_file_size; | |
365 | if (len > 1023) | |
366 | len = 1023; | |
367 | if (bdrv_pread(s->hd, header.backing_file_offset, bs->backing_file, len) != len) | |
368 | goto fail; | |
369 | bs->backing_file[len] = '\0'; | |
370 | } | |
371 | if (qcow_read_snapshots(bs) < 0) | |
372 | goto fail; | |
373 | ||
374 | #ifdef DEBUG_ALLOC | |
375 | check_refcounts(bs); | |
376 | #endif | |
377 | return 0; | |
378 | ||
379 | fail: | |
380 | qcow_free_snapshots(bs); | |
381 | refcount_close(bs); | |
382 | qemu_free(s->l1_table); | |
383 | qemu_free(s->l2_cache); | |
384 | qemu_free(s->cluster_cache); | |
385 | qemu_free(s->cluster_data); | |
386 | bdrv_delete(s->hd); | |
387 | return -1; | |
388 | } | |
389 | ||
390 | static int qcow_set_key(BlockDriverState *bs, const char *key) | |
391 | { | |
392 | BDRVQcowState *s = bs->opaque; | |
393 | uint8_t keybuf[16]; | |
394 | int len, i; | |
3b46e624 | 395 | |
585f8587 FB |
396 | memset(keybuf, 0, 16); |
397 | len = strlen(key); | |
398 | if (len > 16) | |
399 | len = 16; | |
400 | /* XXX: we could compress the chars to 7 bits to increase | |
401 | entropy */ | |
402 | for(i = 0;i < len;i++) { | |
403 | keybuf[i] = key[i]; | |
404 | } | |
405 | s->crypt_method = s->crypt_method_header; | |
406 | ||
407 | if (AES_set_encrypt_key(keybuf, 128, &s->aes_encrypt_key) != 0) | |
408 | return -1; | |
409 | if (AES_set_decrypt_key(keybuf, 128, &s->aes_decrypt_key) != 0) | |
410 | return -1; | |
411 | #if 0 | |
412 | /* test */ | |
413 | { | |
414 | uint8_t in[16]; | |
415 | uint8_t out[16]; | |
416 | uint8_t tmp[16]; | |
417 | for(i=0;i<16;i++) | |
418 | in[i] = i; | |
419 | AES_encrypt(in, tmp, &s->aes_encrypt_key); | |
420 | AES_decrypt(tmp, out, &s->aes_decrypt_key); | |
421 | for(i = 0; i < 16; i++) | |
422 | printf(" %02x", tmp[i]); | |
423 | printf("\n"); | |
424 | for(i = 0; i < 16; i++) | |
425 | printf(" %02x", out[i]); | |
426 | printf("\n"); | |
427 | } | |
428 | #endif | |
429 | return 0; | |
430 | } | |
431 | ||
432 | /* The crypt function is compatible with the linux cryptoloop | |
433 | algorithm for < 4 GB images. NOTE: out_buf == in_buf is | |
434 | supported */ | |
435 | static void encrypt_sectors(BDRVQcowState *s, int64_t sector_num, | |
436 | uint8_t *out_buf, const uint8_t *in_buf, | |
437 | int nb_sectors, int enc, | |
438 | const AES_KEY *key) | |
439 | { | |
440 | union { | |
441 | uint64_t ll[2]; | |
442 | uint8_t b[16]; | |
443 | } ivec; | |
444 | int i; | |
445 | ||
446 | for(i = 0; i < nb_sectors; i++) { | |
447 | ivec.ll[0] = cpu_to_le64(sector_num); | |
448 | ivec.ll[1] = 0; | |
5fafdf24 | 449 | AES_cbc_encrypt(in_buf, out_buf, 512, key, |
585f8587 FB |
450 | ivec.b, enc); |
451 | sector_num++; | |
452 | in_buf += 512; | |
453 | out_buf += 512; | |
454 | } | |
455 | } | |
456 | ||
457 | static int copy_sectors(BlockDriverState *bs, uint64_t start_sect, | |
458 | uint64_t cluster_offset, int n_start, int n_end) | |
459 | { | |
460 | BDRVQcowState *s = bs->opaque; | |
461 | int n, ret; | |
462 | ||
463 | n = n_end - n_start; | |
464 | if (n <= 0) | |
465 | return 0; | |
466 | ret = qcow_read(bs, start_sect + n_start, s->cluster_data, n); | |
467 | if (ret < 0) | |
468 | return ret; | |
469 | if (s->crypt_method) { | |
5fafdf24 TS |
470 | encrypt_sectors(s, start_sect + n_start, |
471 | s->cluster_data, | |
585f8587 FB |
472 | s->cluster_data, n, 1, |
473 | &s->aes_encrypt_key); | |
474 | } | |
5fafdf24 | 475 | ret = bdrv_write(s->hd, (cluster_offset >> 9) + n_start, |
585f8587 FB |
476 | s->cluster_data, n); |
477 | if (ret < 0) | |
478 | return ret; | |
479 | return 0; | |
480 | } | |
481 | ||
482 | static void l2_cache_reset(BlockDriverState *bs) | |
483 | { | |
484 | BDRVQcowState *s = bs->opaque; | |
485 | ||
486 | memset(s->l2_cache, 0, s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t)); | |
487 | memset(s->l2_cache_offsets, 0, L2_CACHE_SIZE * sizeof(uint64_t)); | |
488 | memset(s->l2_cache_counts, 0, L2_CACHE_SIZE * sizeof(uint32_t)); | |
489 | } | |
490 | ||
491 | static inline int l2_cache_new_entry(BlockDriverState *bs) | |
492 | { | |
493 | BDRVQcowState *s = bs->opaque; | |
494 | uint32_t min_count; | |
495 | int min_index, i; | |
496 | ||
497 | /* find a new entry in the least used one */ | |
498 | min_index = 0; | |
499 | min_count = 0xffffffff; | |
500 | for(i = 0; i < L2_CACHE_SIZE; i++) { | |
501 | if (s->l2_cache_counts[i] < min_count) { | |
502 | min_count = s->l2_cache_counts[i]; | |
503 | min_index = i; | |
504 | } | |
505 | } | |
506 | return min_index; | |
507 | } | |
508 | ||
509 | static int64_t align_offset(int64_t offset, int n) | |
510 | { | |
511 | offset = (offset + n - 1) & ~(n - 1); | |
512 | return offset; | |
513 | } | |
514 | ||
515 | static int grow_l1_table(BlockDriverState *bs, int min_size) | |
516 | { | |
517 | BDRVQcowState *s = bs->opaque; | |
518 | int new_l1_size, new_l1_size2, ret, i; | |
519 | uint64_t *new_l1_table; | |
520 | uint64_t new_l1_table_offset; | |
643e5399 | 521 | uint8_t data[12]; |
585f8587 FB |
522 | |
523 | new_l1_size = s->l1_size; | |
524 | if (min_size <= new_l1_size) | |
525 | return 0; | |
526 | while (min_size > new_l1_size) { | |
527 | new_l1_size = (new_l1_size * 3 + 1) / 2; | |
528 | } | |
529 | #ifdef DEBUG_ALLOC2 | |
530 | printf("grow l1_table from %d to %d\n", s->l1_size, new_l1_size); | |
531 | #endif | |
532 | ||
533 | new_l1_size2 = sizeof(uint64_t) * new_l1_size; | |
534 | new_l1_table = qemu_mallocz(new_l1_size2); | |
585f8587 FB |
535 | memcpy(new_l1_table, s->l1_table, s->l1_size * sizeof(uint64_t)); |
536 | ||
537 | /* write new table (align to cluster) */ | |
538 | new_l1_table_offset = alloc_clusters(bs, new_l1_size2); | |
3b46e624 | 539 | |
585f8587 FB |
540 | for(i = 0; i < s->l1_size; i++) |
541 | new_l1_table[i] = cpu_to_be64(new_l1_table[i]); | |
542 | ret = bdrv_pwrite(s->hd, new_l1_table_offset, new_l1_table, new_l1_size2); | |
543 | if (ret != new_l1_size2) | |
544 | goto fail; | |
545 | for(i = 0; i < s->l1_size; i++) | |
546 | new_l1_table[i] = be64_to_cpu(new_l1_table[i]); | |
3b46e624 | 547 | |
585f8587 | 548 | /* set new table */ |
643e5399 AL |
549 | cpu_to_be32w((uint32_t*)data, new_l1_size); |
550 | cpu_to_be64w((uint64_t*)(data + 4), new_l1_table_offset); | |
551 | if (bdrv_pwrite(s->hd, offsetof(QCowHeader, l1_size), data, | |
552 | sizeof(data)) != sizeof(data)) | |
585f8587 FB |
553 | goto fail; |
554 | qemu_free(s->l1_table); | |
555 | free_clusters(bs, s->l1_table_offset, s->l1_size * sizeof(uint64_t)); | |
556 | s->l1_table_offset = new_l1_table_offset; | |
557 | s->l1_table = new_l1_table; | |
558 | s->l1_size = new_l1_size; | |
559 | return 0; | |
560 | fail: | |
561 | qemu_free(s->l1_table); | |
562 | return -EIO; | |
563 | } | |
564 | ||
108534b9 AL |
565 | /* |
566 | * seek_l2_table | |
585f8587 | 567 | * |
108534b9 AL |
568 | * seek l2_offset in the l2_cache table |
569 | * if not found, return NULL, | |
570 | * if found, | |
571 | * increments the l2 cache hit count of the entry, | |
572 | * if counter overflow, divide by two all counters | |
573 | * return the pointer to the l2 cache entry | |
585f8587 | 574 | * |
108534b9 AL |
575 | */ |
576 | ||
577 | static uint64_t *seek_l2_table(BDRVQcowState *s, uint64_t l2_offset) | |
578 | { | |
579 | int i, j; | |
580 | ||
581 | for(i = 0; i < L2_CACHE_SIZE; i++) { | |
582 | if (l2_offset == s->l2_cache_offsets[i]) { | |
583 | /* increment the hit count */ | |
584 | if (++s->l2_cache_counts[i] == 0xffffffff) { | |
585 | for(j = 0; j < L2_CACHE_SIZE; j++) { | |
586 | s->l2_cache_counts[j] >>= 1; | |
587 | } | |
588 | } | |
589 | return s->l2_cache + (i << s->l2_bits); | |
590 | } | |
591 | } | |
592 | return NULL; | |
593 | } | |
594 | ||
595 | /* | |
596 | * l2_load | |
597 | * | |
598 | * Loads a L2 table into memory. If the table is in the cache, the cache | |
599 | * is used; otherwise the L2 table is loaded from the image file. | |
600 | * | |
601 | * Returns a pointer to the L2 table on success, or NULL if the read from | |
602 | * the image file failed. | |
603 | */ | |
604 | ||
605 | static uint64_t *l2_load(BlockDriverState *bs, uint64_t l2_offset) | |
606 | { | |
607 | BDRVQcowState *s = bs->opaque; | |
608 | int min_index; | |
609 | uint64_t *l2_table; | |
610 | ||
611 | /* seek if the table for the given offset is in the cache */ | |
612 | ||
613 | l2_table = seek_l2_table(s, l2_offset); | |
614 | if (l2_table != NULL) | |
615 | return l2_table; | |
616 | ||
617 | /* not found: load a new entry in the least used one */ | |
618 | ||
619 | min_index = l2_cache_new_entry(bs); | |
620 | l2_table = s->l2_cache + (min_index << s->l2_bits); | |
621 | if (bdrv_pread(s->hd, l2_offset, l2_table, s->l2_size * sizeof(uint64_t)) != | |
622 | s->l2_size * sizeof(uint64_t)) | |
623 | return NULL; | |
624 | s->l2_cache_offsets[min_index] = l2_offset; | |
625 | s->l2_cache_counts[min_index] = 1; | |
626 | ||
627 | return l2_table; | |
628 | } | |
629 | ||
630 | /* | |
631 | * l2_allocate | |
585f8587 | 632 | * |
108534b9 AL |
633 | * Allocate a new l2 entry in the file. If l1_index points to an already |
634 | * used entry in the L2 table (i.e. we are doing a copy on write for the L2 | |
635 | * table) copy the contents of the old L2 table into the newly allocated one. | |
636 | * Otherwise the new table is initialized with zeros. | |
585f8587 | 637 | * |
585f8587 | 638 | */ |
108534b9 AL |
639 | |
640 | static uint64_t *l2_allocate(BlockDriverState *bs, int l1_index) | |
641 | { | |
642 | BDRVQcowState *s = bs->opaque; | |
643 | int min_index; | |
644 | uint64_t old_l2_offset, tmp; | |
645 | uint64_t *l2_table, l2_offset; | |
646 | ||
647 | old_l2_offset = s->l1_table[l1_index]; | |
648 | ||
649 | /* allocate a new l2 entry */ | |
650 | ||
651 | l2_offset = alloc_clusters(bs, s->l2_size * sizeof(uint64_t)); | |
652 | ||
653 | /* update the L1 entry */ | |
654 | ||
655 | s->l1_table[l1_index] = l2_offset | QCOW_OFLAG_COPIED; | |
656 | ||
657 | tmp = cpu_to_be64(l2_offset | QCOW_OFLAG_COPIED); | |
658 | if (bdrv_pwrite(s->hd, s->l1_table_offset + l1_index * sizeof(tmp), | |
659 | &tmp, sizeof(tmp)) != sizeof(tmp)) | |
660 | return NULL; | |
661 | ||
662 | /* allocate a new entry in the l2 cache */ | |
663 | ||
664 | min_index = l2_cache_new_entry(bs); | |
665 | l2_table = s->l2_cache + (min_index << s->l2_bits); | |
666 | ||
667 | if (old_l2_offset == 0) { | |
668 | /* if there was no old l2 table, clear the new table */ | |
669 | memset(l2_table, 0, s->l2_size * sizeof(uint64_t)); | |
670 | } else { | |
671 | /* if there was an old l2 table, read it from the disk */ | |
672 | if (bdrv_pread(s->hd, old_l2_offset, | |
673 | l2_table, s->l2_size * sizeof(uint64_t)) != | |
674 | s->l2_size * sizeof(uint64_t)) | |
675 | return NULL; | |
676 | } | |
677 | /* write the l2 table to the file */ | |
678 | if (bdrv_pwrite(s->hd, l2_offset, | |
679 | l2_table, s->l2_size * sizeof(uint64_t)) != | |
680 | s->l2_size * sizeof(uint64_t)) | |
681 | return NULL; | |
682 | ||
683 | /* update the l2 cache entry */ | |
684 | ||
685 | s->l2_cache_offsets[min_index] = l2_offset; | |
686 | s->l2_cache_counts[min_index] = 1; | |
687 | ||
688 | return l2_table; | |
689 | } | |
690 | ||
6db6c638 AL |
691 | static int size_to_clusters(BDRVQcowState *s, int64_t size) |
692 | { | |
693 | return (size + (s->cluster_size - 1)) >> s->cluster_bits; | |
694 | } | |
695 | ||
696 | static int count_contiguous_clusters(uint64_t nb_clusters, int cluster_size, | |
ff4b91c2 | 697 | uint64_t *l2_table, uint64_t start, uint64_t mask) |
6db6c638 AL |
698 | { |
699 | int i; | |
700 | uint64_t offset = be64_to_cpu(l2_table[0]) & ~mask; | |
701 | ||
ab5ccbd6 AL |
702 | if (!offset) |
703 | return 0; | |
704 | ||
ff4b91c2 | 705 | for (i = start; i < start + nb_clusters; i++) |
6db6c638 AL |
706 | if (offset + i * cluster_size != (be64_to_cpu(l2_table[i]) & ~mask)) |
707 | break; | |
708 | ||
ff4b91c2 | 709 | return (i - start); |
6db6c638 AL |
710 | } |
711 | ||
712 | static int count_contiguous_free_clusters(uint64_t nb_clusters, uint64_t *l2_table) | |
713 | { | |
714 | int i = 0; | |
715 | ||
716 | while(nb_clusters-- && l2_table[i] == 0) | |
717 | i++; | |
718 | ||
719 | return i; | |
720 | } | |
721 | ||
05203524 AL |
722 | /* |
723 | * get_cluster_offset | |
724 | * | |
725 | * For a given offset of the disk image, return cluster offset in | |
726 | * qcow2 file. | |
727 | * | |
095a9c58 AL |
728 | * on entry, *num is the number of contiguous clusters we'd like to |
729 | * access following offset. | |
730 | * | |
731 | * on exit, *num is the number of contiguous clusters we can read. | |
732 | * | |
05203524 AL |
733 | * Return 1, if the offset is found |
734 | * Return 0, otherwise. | |
735 | * | |
736 | */ | |
737 | ||
095a9c58 AL |
738 | static uint64_t get_cluster_offset(BlockDriverState *bs, |
739 | uint64_t offset, int *num) | |
05203524 AL |
740 | { |
741 | BDRVQcowState *s = bs->opaque; | |
742 | int l1_index, l2_index; | |
6db6c638 AL |
743 | uint64_t l2_offset, *l2_table, cluster_offset; |
744 | int l1_bits, c; | |
745 | int index_in_cluster, nb_available, nb_needed, nb_clusters; | |
095a9c58 AL |
746 | |
747 | index_in_cluster = (offset >> 9) & (s->cluster_sectors - 1); | |
748 | nb_needed = *num + index_in_cluster; | |
749 | ||
750 | l1_bits = s->l2_bits + s->cluster_bits; | |
751 | ||
752 | /* compute how many bytes there are between the offset and | |
6db6c638 | 753 | * the end of the l1 entry |
095a9c58 AL |
754 | */ |
755 | ||
756 | nb_available = (1 << l1_bits) - (offset & ((1 << l1_bits) - 1)); | |
757 | ||
758 | /* compute the number of available sectors */ | |
759 | ||
760 | nb_available = (nb_available >> 9) + index_in_cluster; | |
761 | ||
f8de1660 AL |
762 | if (nb_needed > nb_available) { |
763 | nb_needed = nb_available; | |
764 | } | |
765 | ||
095a9c58 | 766 | cluster_offset = 0; |
05203524 AL |
767 | |
768 | /* seek the the l2 offset in the l1 table */ | |
769 | ||
095a9c58 | 770 | l1_index = offset >> l1_bits; |
05203524 | 771 | if (l1_index >= s->l1_size) |
095a9c58 | 772 | goto out; |
05203524 AL |
773 | |
774 | l2_offset = s->l1_table[l1_index]; | |
775 | ||
776 | /* seek the l2 table of the given l2 offset */ | |
777 | ||
778 | if (!l2_offset) | |
095a9c58 | 779 | goto out; |
05203524 AL |
780 | |
781 | /* load the l2 table in memory */ | |
782 | ||
783 | l2_offset &= ~QCOW_OFLAG_COPIED; | |
784 | l2_table = l2_load(bs, l2_offset); | |
785 | if (l2_table == NULL) | |
768706a5 | 786 | return 0; |
05203524 AL |
787 | |
788 | /* find the cluster offset for the given disk offset */ | |
789 | ||
790 | l2_index = (offset >> s->cluster_bits) & (s->l2_size - 1); | |
791 | cluster_offset = be64_to_cpu(l2_table[l2_index]); | |
6db6c638 | 792 | nb_clusters = size_to_clusters(s, nb_needed << 9); |
095a9c58 AL |
793 | |
794 | if (!cluster_offset) { | |
6db6c638 AL |
795 | /* how many empty clusters ? */ |
796 | c = count_contiguous_free_clusters(nb_clusters, &l2_table[l2_index]); | |
095a9c58 | 797 | } else { |
6db6c638 AL |
798 | /* how many allocated clusters ? */ |
799 | c = count_contiguous_clusters(nb_clusters, s->cluster_size, | |
ff4b91c2 | 800 | &l2_table[l2_index], 0, QCOW_OFLAG_COPIED); |
6db6c638 | 801 | } |
095a9c58 | 802 | |
6db6c638 | 803 | nb_available = (c * s->cluster_sectors); |
095a9c58 AL |
804 | out: |
805 | if (nb_available > nb_needed) | |
806 | nb_available = nb_needed; | |
807 | ||
808 | *num = nb_available - index_in_cluster; | |
809 | ||
6db6c638 | 810 | return cluster_offset & ~QCOW_OFLAG_COPIED; |
05203524 AL |
811 | } |
812 | ||
813 | /* | |
52d893ec | 814 | * free_any_clusters |
05203524 | 815 | * |
52d893ec | 816 | * free clusters according to its type: compressed or not |
05203524 | 817 | * |
52d893ec AL |
818 | */ |
819 | ||
820 | static void free_any_clusters(BlockDriverState *bs, | |
095a9c58 | 821 | uint64_t cluster_offset, int nb_clusters) |
52d893ec AL |
822 | { |
823 | BDRVQcowState *s = bs->opaque; | |
824 | ||
52d893ec AL |
825 | /* free the cluster */ |
826 | ||
827 | if (cluster_offset & QCOW_OFLAG_COMPRESSED) { | |
828 | int nb_csectors; | |
829 | nb_csectors = ((cluster_offset >> s->csize_shift) & | |
830 | s->csize_mask) + 1; | |
831 | free_clusters(bs, (cluster_offset & s->cluster_offset_mask) & ~511, | |
832 | nb_csectors * 512); | |
833 | return; | |
834 | } | |
835 | ||
095a9c58 AL |
836 | free_clusters(bs, cluster_offset, nb_clusters << s->cluster_bits); |
837 | ||
838 | return; | |
52d893ec AL |
839 | } |
840 | ||
841 | /* | |
842 | * get_cluster_table | |
05203524 | 843 | * |
52d893ec AL |
844 | * for a given disk offset, load (and allocate if needed) |
845 | * the l2 table. | |
846 | * | |
847 | * the l2 table offset in the qcow2 file and the cluster index | |
848 | * in the l2 table are given to the caller. | |
05203524 AL |
849 | * |
850 | */ | |
851 | ||
52d893ec AL |
852 | static int get_cluster_table(BlockDriverState *bs, uint64_t offset, |
853 | uint64_t **new_l2_table, | |
854 | uint64_t *new_l2_offset, | |
855 | int *new_l2_index) | |
585f8587 FB |
856 | { |
857 | BDRVQcowState *s = bs->opaque; | |
108534b9 | 858 | int l1_index, l2_index, ret; |
52d893ec | 859 | uint64_t l2_offset, *l2_table; |
108534b9 AL |
860 | |
861 | /* seek the the l2 offset in the l1 table */ | |
3b46e624 | 862 | |
585f8587 FB |
863 | l1_index = offset >> (s->l2_bits + s->cluster_bits); |
864 | if (l1_index >= s->l1_size) { | |
108534b9 AL |
865 | ret = grow_l1_table(bs, l1_index + 1); |
866 | if (ret < 0) | |
585f8587 FB |
867 | return 0; |
868 | } | |
869 | l2_offset = s->l1_table[l1_index]; | |
108534b9 AL |
870 | |
871 | /* seek the l2 table of the given l2 offset */ | |
872 | ||
05203524 AL |
873 | if (l2_offset & QCOW_OFLAG_COPIED) { |
874 | /* load the l2 table in memory */ | |
875 | l2_offset &= ~QCOW_OFLAG_COPIED; | |
876 | l2_table = l2_load(bs, l2_offset); | |
877 | if (l2_table == NULL) | |
585f8587 | 878 | return 0; |
05203524 AL |
879 | } else { |
880 | if (l2_offset) | |
881 | free_clusters(bs, l2_offset, s->l2_size * sizeof(uint64_t)); | |
108534b9 AL |
882 | l2_table = l2_allocate(bs, l1_index); |
883 | if (l2_table == NULL) | |
585f8587 | 884 | return 0; |
108534b9 | 885 | l2_offset = s->l1_table[l1_index] & ~QCOW_OFLAG_COPIED; |
585f8587 | 886 | } |
108534b9 AL |
887 | |
888 | /* find the cluster offset for the given disk offset */ | |
889 | ||
585f8587 | 890 | l2_index = (offset >> s->cluster_bits) & (s->l2_size - 1); |
05203524 | 891 | |
52d893ec AL |
892 | *new_l2_table = l2_table; |
893 | *new_l2_offset = l2_offset; | |
894 | *new_l2_index = l2_index; | |
895 | ||
896 | return 1; | |
897 | } | |
898 | ||
899 | /* | |
900 | * alloc_compressed_cluster_offset | |
901 | * | |
902 | * For a given offset of the disk image, return cluster offset in | |
903 | * qcow2 file. | |
904 | * | |
905 | * If the offset is not found, allocate a new compressed cluster. | |
906 | * | |
907 | * Return the cluster offset if successful, | |
908 | * Return 0, otherwise. | |
909 | * | |
910 | */ | |
911 | ||
912 | static uint64_t alloc_compressed_cluster_offset(BlockDriverState *bs, | |
913 | uint64_t offset, | |
914 | int compressed_size) | |
915 | { | |
916 | BDRVQcowState *s = bs->opaque; | |
917 | int l2_index, ret; | |
918 | uint64_t l2_offset, *l2_table, cluster_offset; | |
919 | int nb_csectors; | |
920 | ||
921 | ret = get_cluster_table(bs, offset, &l2_table, &l2_offset, &l2_index); | |
922 | if (ret == 0) | |
923 | return 0; | |
924 | ||
925 | cluster_offset = be64_to_cpu(l2_table[l2_index]); | |
05203524 AL |
926 | if (cluster_offset & QCOW_OFLAG_COPIED) |
927 | return cluster_offset & ~QCOW_OFLAG_COPIED; | |
928 | ||
095a9c58 AL |
929 | if (cluster_offset) |
930 | free_any_clusters(bs, cluster_offset, 1); | |
108534b9 | 931 | |
52d893ec AL |
932 | cluster_offset = alloc_bytes(bs, compressed_size); |
933 | nb_csectors = ((cluster_offset + compressed_size - 1) >> 9) - | |
934 | (cluster_offset >> 9); | |
05203524 | 935 | |
52d893ec AL |
936 | cluster_offset |= QCOW_OFLAG_COMPRESSED | |
937 | ((uint64_t)nb_csectors << s->csize_shift); | |
05203524 | 938 | |
52d893ec | 939 | /* update L2 table */ |
05203524 | 940 | |
52d893ec | 941 | /* compressed clusters never have the copied flag */ |
05203524 | 942 | |
52d893ec AL |
943 | l2_table[l2_index] = cpu_to_be64(cluster_offset); |
944 | if (bdrv_pwrite(s->hd, | |
945 | l2_offset + l2_index * sizeof(uint64_t), | |
946 | l2_table + l2_index, | |
947 | sizeof(uint64_t)) != sizeof(uint64_t)) | |
948 | return 0; | |
05203524 | 949 | |
52d893ec AL |
950 | return cluster_offset; |
951 | } | |
05203524 | 952 | |
e976c6a1 AL |
953 | typedef struct QCowL2Meta |
954 | { | |
955 | uint64_t offset; | |
956 | int n_start; | |
957 | int nb_available; | |
958 | int nb_clusters; | |
959 | } QCowL2Meta; | |
960 | ||
961 | static int alloc_cluster_link_l2(BlockDriverState *bs, uint64_t cluster_offset, | |
962 | QCowL2Meta *m) | |
963 | { | |
964 | BDRVQcowState *s = bs->opaque; | |
965 | int i, j = 0, l2_index, ret; | |
966 | uint64_t *old_cluster, start_sect, l2_offset, *l2_table; | |
967 | ||
968 | if (m->nb_clusters == 0) | |
969 | return 0; | |
970 | ||
3ec88e80 | 971 | old_cluster = qemu_malloc(m->nb_clusters * sizeof(uint64_t)); |
e976c6a1 AL |
972 | |
973 | /* copy content of unmodified sectors */ | |
974 | start_sect = (m->offset & ~(s->cluster_size - 1)) >> 9; | |
975 | if (m->n_start) { | |
976 | ret = copy_sectors(bs, start_sect, cluster_offset, 0, m->n_start); | |
977 | if (ret < 0) | |
978 | goto err; | |
979 | } | |
980 | ||
981 | if (m->nb_available & (s->cluster_sectors - 1)) { | |
982 | uint64_t end = m->nb_available & ~(uint64_t)(s->cluster_sectors - 1); | |
983 | ret = copy_sectors(bs, start_sect + end, cluster_offset + (end << 9), | |
984 | m->nb_available - end, s->cluster_sectors); | |
985 | if (ret < 0) | |
986 | goto err; | |
987 | } | |
988 | ||
989 | ret = -EIO; | |
990 | /* update L2 table */ | |
991 | if (!get_cluster_table(bs, m->offset, &l2_table, &l2_offset, &l2_index)) | |
992 | goto err; | |
993 | ||
994 | for (i = 0; i < m->nb_clusters; i++) { | |
995 | if(l2_table[l2_index + i] != 0) | |
996 | old_cluster[j++] = l2_table[l2_index + i]; | |
997 | ||
998 | l2_table[l2_index + i] = cpu_to_be64((cluster_offset + | |
999 | (i << s->cluster_bits)) | QCOW_OFLAG_COPIED); | |
1000 | } | |
1001 | ||
1002 | if (bdrv_pwrite(s->hd, l2_offset + l2_index * sizeof(uint64_t), | |
1003 | l2_table + l2_index, m->nb_clusters * sizeof(uint64_t)) != | |
1004 | m->nb_clusters * sizeof(uint64_t)) | |
1005 | goto err; | |
1006 | ||
1007 | for (i = 0; i < j; i++) | |
641636d1 | 1008 | free_any_clusters(bs, be64_to_cpu(old_cluster[i]), 1); |
e976c6a1 AL |
1009 | |
1010 | ret = 0; | |
1011 | err: | |
1012 | qemu_free(old_cluster); | |
1013 | return ret; | |
1014 | } | |
1015 | ||
52d893ec AL |
1016 | /* |
1017 | * alloc_cluster_offset | |
1018 | * | |
1019 | * For a given offset of the disk image, return cluster offset in | |
1020 | * qcow2 file. | |
1021 | * | |
1022 | * If the offset is not found, allocate a new cluster. | |
1023 | * | |
1024 | * Return the cluster offset if successful, | |
1025 | * Return 0, otherwise. | |
1026 | * | |
1027 | */ | |
1028 | ||
1029 | static uint64_t alloc_cluster_offset(BlockDriverState *bs, | |
1030 | uint64_t offset, | |
095a9c58 | 1031 | int n_start, int n_end, |
e976c6a1 | 1032 | int *num, QCowL2Meta *m) |
52d893ec AL |
1033 | { |
1034 | BDRVQcowState *s = bs->opaque; | |
1035 | int l2_index, ret; | |
1036 | uint64_t l2_offset, *l2_table, cluster_offset; | |
e976c6a1 | 1037 | int nb_clusters, i = 0; |
52d893ec AL |
1038 | |
1039 | ret = get_cluster_table(bs, offset, &l2_table, &l2_offset, &l2_index); | |
1040 | if (ret == 0) | |
1041 | return 0; | |
1042 | ||
6db6c638 AL |
1043 | nb_clusters = size_to_clusters(s, n_end << 9); |
1044 | ||
e976c6a1 | 1045 | nb_clusters = MIN(nb_clusters, s->l2_size - l2_index); |
095a9c58 | 1046 | |
52d893ec | 1047 | cluster_offset = be64_to_cpu(l2_table[l2_index]); |
52d893ec | 1048 | |
095a9c58 AL |
1049 | /* We keep all QCOW_OFLAG_COPIED clusters */ |
1050 | ||
1051 | if (cluster_offset & QCOW_OFLAG_COPIED) { | |
6db6c638 | 1052 | nb_clusters = count_contiguous_clusters(nb_clusters, s->cluster_size, |
ff4b91c2 | 1053 | &l2_table[l2_index], 0, 0); |
095a9c58 | 1054 | |
095a9c58 | 1055 | cluster_offset &= ~QCOW_OFLAG_COPIED; |
e976c6a1 | 1056 | m->nb_clusters = 0; |
095a9c58 AL |
1057 | |
1058 | goto out; | |
1059 | } | |
1060 | ||
1061 | /* for the moment, multiple compressed clusters are not managed */ | |
1062 | ||
1063 | if (cluster_offset & QCOW_OFLAG_COMPRESSED) | |
1064 | nb_clusters = 1; | |
1065 | ||
bc352085 | 1066 | /* how many available clusters ? */ |
095a9c58 | 1067 | |
bc352085 | 1068 | while (i < nb_clusters) { |
ab5ccbd6 | 1069 | i += count_contiguous_clusters(nb_clusters - i, s->cluster_size, |
ff4b91c2 | 1070 | &l2_table[l2_index], i, 0); |
ab5ccbd6 AL |
1071 | |
1072 | if(be64_to_cpu(l2_table[l2_index + i])) | |
1073 | break; | |
1074 | ||
6db6c638 AL |
1075 | i += count_contiguous_free_clusters(nb_clusters - i, |
1076 | &l2_table[l2_index + i]); | |
095a9c58 | 1077 | |
6db6c638 | 1078 | cluster_offset = be64_to_cpu(l2_table[l2_index + i]); |
095a9c58 | 1079 | |
6db6c638 | 1080 | if ((cluster_offset & QCOW_OFLAG_COPIED) || |
bc352085 | 1081 | (cluster_offset & QCOW_OFLAG_COMPRESSED)) |
6db6c638 | 1082 | break; |
095a9c58 | 1083 | } |
bc352085 | 1084 | nb_clusters = i; |
05203524 AL |
1085 | |
1086 | /* allocate a new cluster */ | |
1087 | ||
095a9c58 | 1088 | cluster_offset = alloc_clusters(bs, nb_clusters * s->cluster_size); |
05203524 | 1089 | |
e976c6a1 AL |
1090 | /* save info needed for meta data update */ |
1091 | m->offset = offset; | |
1092 | m->n_start = n_start; | |
1093 | m->nb_clusters = nb_clusters; | |
05203524 | 1094 | |
095a9c58 | 1095 | out: |
e976c6a1 AL |
1096 | m->nb_available = MIN(nb_clusters << (s->cluster_bits - 9), n_end); |
1097 | ||
1098 | *num = m->nb_available - n_start; | |
095a9c58 | 1099 | |
585f8587 FB |
1100 | return cluster_offset; |
1101 | } | |
1102 | ||
5fafdf24 | 1103 | static int qcow_is_allocated(BlockDriverState *bs, int64_t sector_num, |
585f8587 FB |
1104 | int nb_sectors, int *pnum) |
1105 | { | |
585f8587 FB |
1106 | uint64_t cluster_offset; |
1107 | ||
095a9c58 AL |
1108 | *pnum = nb_sectors; |
1109 | cluster_offset = get_cluster_offset(bs, sector_num << 9, pnum); | |
1110 | ||
585f8587 FB |
1111 | return (cluster_offset != 0); |
1112 | } | |
1113 | ||
1114 | static int decompress_buffer(uint8_t *out_buf, int out_buf_size, | |
1115 | const uint8_t *buf, int buf_size) | |
1116 | { | |
1117 | z_stream strm1, *strm = &strm1; | |
1118 | int ret, out_len; | |
1119 | ||
1120 | memset(strm, 0, sizeof(*strm)); | |
1121 | ||
1122 | strm->next_in = (uint8_t *)buf; | |
1123 | strm->avail_in = buf_size; | |
1124 | strm->next_out = out_buf; | |
1125 | strm->avail_out = out_buf_size; | |
1126 | ||
1127 | ret = inflateInit2(strm, -12); | |
1128 | if (ret != Z_OK) | |
1129 | return -1; | |
1130 | ret = inflate(strm, Z_FINISH); | |
1131 | out_len = strm->next_out - out_buf; | |
1132 | if ((ret != Z_STREAM_END && ret != Z_BUF_ERROR) || | |
1133 | out_len != out_buf_size) { | |
1134 | inflateEnd(strm); | |
1135 | return -1; | |
1136 | } | |
1137 | inflateEnd(strm); | |
1138 | return 0; | |
1139 | } | |
3b46e624 | 1140 | |
585f8587 FB |
1141 | static int decompress_cluster(BDRVQcowState *s, uint64_t cluster_offset) |
1142 | { | |
1143 | int ret, csize, nb_csectors, sector_offset; | |
1144 | uint64_t coffset; | |
1145 | ||
1146 | coffset = cluster_offset & s->cluster_offset_mask; | |
1147 | if (s->cluster_cache_offset != coffset) { | |
1148 | nb_csectors = ((cluster_offset >> s->csize_shift) & s->csize_mask) + 1; | |
1149 | sector_offset = coffset & 511; | |
1150 | csize = nb_csectors * 512 - sector_offset; | |
1151 | ret = bdrv_read(s->hd, coffset >> 9, s->cluster_data, nb_csectors); | |
1152 | if (ret < 0) { | |
1153 | return -1; | |
1154 | } | |
1155 | if (decompress_buffer(s->cluster_cache, s->cluster_size, | |
1156 | s->cluster_data + sector_offset, csize) < 0) { | |
1157 | return -1; | |
1158 | } | |
1159 | s->cluster_cache_offset = coffset; | |
1160 | } | |
1161 | return 0; | |
1162 | } | |
1163 | ||
a9465922 | 1164 | /* handle reading after the end of the backing file */ |
5fafdf24 | 1165 | static int backing_read1(BlockDriverState *bs, |
a9465922 FB |
1166 | int64_t sector_num, uint8_t *buf, int nb_sectors) |
1167 | { | |
1168 | int n1; | |
1169 | if ((sector_num + nb_sectors) <= bs->total_sectors) | |
1170 | return nb_sectors; | |
1171 | if (sector_num >= bs->total_sectors) | |
1172 | n1 = 0; | |
1173 | else | |
1174 | n1 = bs->total_sectors - sector_num; | |
1175 | memset(buf + n1 * 512, 0, 512 * (nb_sectors - n1)); | |
1176 | return n1; | |
1177 | } | |
1178 | ||
5fafdf24 | 1179 | static int qcow_read(BlockDriverState *bs, int64_t sector_num, |
585f8587 FB |
1180 | uint8_t *buf, int nb_sectors) |
1181 | { | |
1182 | BDRVQcowState *s = bs->opaque; | |
a9465922 | 1183 | int ret, index_in_cluster, n, n1; |
585f8587 | 1184 | uint64_t cluster_offset; |
3b46e624 | 1185 | |
585f8587 | 1186 | while (nb_sectors > 0) { |
095a9c58 AL |
1187 | n = nb_sectors; |
1188 | cluster_offset = get_cluster_offset(bs, sector_num << 9, &n); | |
585f8587 | 1189 | index_in_cluster = sector_num & (s->cluster_sectors - 1); |
585f8587 FB |
1190 | if (!cluster_offset) { |
1191 | if (bs->backing_hd) { | |
1192 | /* read from the base image */ | |
a9465922 FB |
1193 | n1 = backing_read1(bs->backing_hd, sector_num, buf, n); |
1194 | if (n1 > 0) { | |
1195 | ret = bdrv_read(bs->backing_hd, sector_num, buf, n1); | |
1196 | if (ret < 0) | |
1197 | return -1; | |
1198 | } | |
585f8587 FB |
1199 | } else { |
1200 | memset(buf, 0, 512 * n); | |
1201 | } | |
1202 | } else if (cluster_offset & QCOW_OFLAG_COMPRESSED) { | |
1203 | if (decompress_cluster(s, cluster_offset) < 0) | |
1204 | return -1; | |
1205 | memcpy(buf, s->cluster_cache + index_in_cluster * 512, 512 * n); | |
1206 | } else { | |
1207 | ret = bdrv_pread(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512); | |
5fafdf24 | 1208 | if (ret != n * 512) |
585f8587 FB |
1209 | return -1; |
1210 | if (s->crypt_method) { | |
5fafdf24 | 1211 | encrypt_sectors(s, sector_num, buf, buf, n, 0, |
585f8587 FB |
1212 | &s->aes_decrypt_key); |
1213 | } | |
1214 | } | |
1215 | nb_sectors -= n; | |
1216 | sector_num += n; | |
1217 | buf += n * 512; | |
1218 | } | |
1219 | return 0; | |
1220 | } | |
1221 | ||
5fafdf24 | 1222 | static int qcow_write(BlockDriverState *bs, int64_t sector_num, |
585f8587 FB |
1223 | const uint8_t *buf, int nb_sectors) |
1224 | { | |
1225 | BDRVQcowState *s = bs->opaque; | |
1226 | int ret, index_in_cluster, n; | |
1227 | uint64_t cluster_offset; | |
095a9c58 | 1228 | int n_end; |
e976c6a1 | 1229 | QCowL2Meta l2meta; |
3b46e624 | 1230 | |
585f8587 FB |
1231 | while (nb_sectors > 0) { |
1232 | index_in_cluster = sector_num & (s->cluster_sectors - 1); | |
095a9c58 AL |
1233 | n_end = index_in_cluster + nb_sectors; |
1234 | if (s->crypt_method && | |
1235 | n_end > QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors) | |
1236 | n_end = QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors; | |
52d893ec | 1237 | cluster_offset = alloc_cluster_offset(bs, sector_num << 9, |
05203524 | 1238 | index_in_cluster, |
e976c6a1 | 1239 | n_end, &n, &l2meta); |
585f8587 FB |
1240 | if (!cluster_offset) |
1241 | return -1; | |
1242 | if (s->crypt_method) { | |
1243 | encrypt_sectors(s, sector_num, s->cluster_data, buf, n, 1, | |
1244 | &s->aes_encrypt_key); | |
5fafdf24 | 1245 | ret = bdrv_pwrite(s->hd, cluster_offset + index_in_cluster * 512, |
585f8587 FB |
1246 | s->cluster_data, n * 512); |
1247 | } else { | |
1248 | ret = bdrv_pwrite(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512); | |
1249 | } | |
e976c6a1 AL |
1250 | if (ret != n * 512 || alloc_cluster_link_l2(bs, cluster_offset, &l2meta) < 0) { |
1251 | free_any_clusters(bs, cluster_offset, l2meta.nb_clusters); | |
585f8587 | 1252 | return -1; |
e976c6a1 | 1253 | } |
585f8587 FB |
1254 | nb_sectors -= n; |
1255 | sector_num += n; | |
1256 | buf += n * 512; | |
1257 | } | |
1258 | s->cluster_cache_offset = -1; /* disable compressed cache */ | |
1259 | return 0; | |
1260 | } | |
1261 | ||
ce1a14dc PB |
1262 | typedef struct QCowAIOCB { |
1263 | BlockDriverAIOCB common; | |
585f8587 | 1264 | int64_t sector_num; |
f141eafe | 1265 | QEMUIOVector *qiov; |
585f8587 | 1266 | uint8_t *buf; |
f141eafe | 1267 | void *orig_buf; |
585f8587 FB |
1268 | int nb_sectors; |
1269 | int n; | |
1270 | uint64_t cluster_offset; | |
5fafdf24 | 1271 | uint8_t *cluster_data; |
585f8587 | 1272 | BlockDriverAIOCB *hd_aiocb; |
c87c0672 AL |
1273 | struct iovec hd_iov; |
1274 | QEMUIOVector hd_qiov; | |
1490791f | 1275 | QEMUBH *bh; |
e976c6a1 | 1276 | QCowL2Meta l2meta; |
585f8587 FB |
1277 | } QCowAIOCB; |
1278 | ||
1490791f AL |
1279 | static void qcow_aio_read_cb(void *opaque, int ret); |
1280 | static void qcow_aio_read_bh(void *opaque) | |
1281 | { | |
1282 | QCowAIOCB *acb = opaque; | |
1283 | qemu_bh_delete(acb->bh); | |
1284 | acb->bh = NULL; | |
1285 | qcow_aio_read_cb(opaque, 0); | |
1286 | } | |
1287 | ||
a32ef786 AL |
1288 | static int qcow_schedule_bh(QEMUBHFunc *cb, QCowAIOCB *acb) |
1289 | { | |
1290 | if (acb->bh) | |
1291 | return -EIO; | |
1292 | ||
1293 | acb->bh = qemu_bh_new(cb, acb); | |
1294 | if (!acb->bh) | |
1295 | return -EIO; | |
1296 | ||
1297 | qemu_bh_schedule(acb->bh); | |
1298 | ||
1299 | return 0; | |
1300 | } | |
1301 | ||
585f8587 FB |
1302 | static void qcow_aio_read_cb(void *opaque, int ret) |
1303 | { | |
ce1a14dc PB |
1304 | QCowAIOCB *acb = opaque; |
1305 | BlockDriverState *bs = acb->common.bs; | |
585f8587 | 1306 | BDRVQcowState *s = bs->opaque; |
a9465922 | 1307 | int index_in_cluster, n1; |
585f8587 | 1308 | |
ce1a14dc | 1309 | acb->hd_aiocb = NULL; |
f141eafe AL |
1310 | if (ret < 0) |
1311 | goto done; | |
585f8587 | 1312 | |
585f8587 | 1313 | /* post process the read buffer */ |
ce1a14dc | 1314 | if (!acb->cluster_offset) { |
585f8587 | 1315 | /* nothing to do */ |
ce1a14dc | 1316 | } else if (acb->cluster_offset & QCOW_OFLAG_COMPRESSED) { |
585f8587 FB |
1317 | /* nothing to do */ |
1318 | } else { | |
1319 | if (s->crypt_method) { | |
5fafdf24 TS |
1320 | encrypt_sectors(s, acb->sector_num, acb->buf, acb->buf, |
1321 | acb->n, 0, | |
585f8587 FB |
1322 | &s->aes_decrypt_key); |
1323 | } | |
1324 | } | |
1325 | ||
ce1a14dc PB |
1326 | acb->nb_sectors -= acb->n; |
1327 | acb->sector_num += acb->n; | |
1328 | acb->buf += acb->n * 512; | |
585f8587 | 1329 | |
ce1a14dc | 1330 | if (acb->nb_sectors == 0) { |
585f8587 | 1331 | /* request completed */ |
f141eafe AL |
1332 | ret = 0; |
1333 | goto done; | |
585f8587 | 1334 | } |
3b46e624 | 1335 | |
585f8587 | 1336 | /* prepare next AIO request */ |
095a9c58 AL |
1337 | acb->n = acb->nb_sectors; |
1338 | acb->cluster_offset = get_cluster_offset(bs, acb->sector_num << 9, &acb->n); | |
ce1a14dc | 1339 | index_in_cluster = acb->sector_num & (s->cluster_sectors - 1); |
ce1a14dc PB |
1340 | |
1341 | if (!acb->cluster_offset) { | |
585f8587 FB |
1342 | if (bs->backing_hd) { |
1343 | /* read from the base image */ | |
5fafdf24 | 1344 | n1 = backing_read1(bs->backing_hd, acb->sector_num, |
ce1a14dc | 1345 | acb->buf, acb->n); |
a9465922 | 1346 | if (n1 > 0) { |
3f4cb3d3 | 1347 | acb->hd_iov.iov_base = (void *)acb->buf; |
c87c0672 AL |
1348 | acb->hd_iov.iov_len = acb->n * 512; |
1349 | qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1); | |
1350 | acb->hd_aiocb = bdrv_aio_readv(bs->backing_hd, acb->sector_num, | |
1351 | &acb->hd_qiov, acb->n, | |
1352 | qcow_aio_read_cb, acb); | |
ce1a14dc | 1353 | if (acb->hd_aiocb == NULL) |
f141eafe | 1354 | goto done; |
a9465922 | 1355 | } else { |
a32ef786 AL |
1356 | ret = qcow_schedule_bh(qcow_aio_read_bh, acb); |
1357 | if (ret < 0) | |
f141eafe | 1358 | goto done; |
a9465922 | 1359 | } |
585f8587 FB |
1360 | } else { |
1361 | /* Note: in this case, no need to wait */ | |
ce1a14dc | 1362 | memset(acb->buf, 0, 512 * acb->n); |
a32ef786 AL |
1363 | ret = qcow_schedule_bh(qcow_aio_read_bh, acb); |
1364 | if (ret < 0) | |
f141eafe | 1365 | goto done; |
585f8587 | 1366 | } |
ce1a14dc | 1367 | } else if (acb->cluster_offset & QCOW_OFLAG_COMPRESSED) { |
585f8587 | 1368 | /* add AIO support for compressed blocks ? */ |
ce1a14dc | 1369 | if (decompress_cluster(s, acb->cluster_offset) < 0) |
f141eafe | 1370 | goto done; |
5fafdf24 | 1371 | memcpy(acb->buf, |
ce1a14dc | 1372 | s->cluster_cache + index_in_cluster * 512, 512 * acb->n); |
a32ef786 AL |
1373 | ret = qcow_schedule_bh(qcow_aio_read_bh, acb); |
1374 | if (ret < 0) | |
f141eafe | 1375 | goto done; |
585f8587 | 1376 | } else { |
ce1a14dc | 1377 | if ((acb->cluster_offset & 511) != 0) { |
585f8587 | 1378 | ret = -EIO; |
f141eafe | 1379 | goto done; |
585f8587 | 1380 | } |
c87c0672 | 1381 | |
3f4cb3d3 | 1382 | acb->hd_iov.iov_base = (void *)acb->buf; |
c87c0672 AL |
1383 | acb->hd_iov.iov_len = acb->n * 512; |
1384 | qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1); | |
1385 | acb->hd_aiocb = bdrv_aio_readv(s->hd, | |
5fafdf24 | 1386 | (acb->cluster_offset >> 9) + index_in_cluster, |
c87c0672 | 1387 | &acb->hd_qiov, acb->n, qcow_aio_read_cb, acb); |
ce1a14dc | 1388 | if (acb->hd_aiocb == NULL) |
f141eafe AL |
1389 | goto done; |
1390 | } | |
1391 | ||
1392 | return; | |
1393 | done: | |
1394 | if (acb->qiov->niov > 1) { | |
1395 | qemu_iovec_from_buffer(acb->qiov, acb->orig_buf, acb->qiov->size); | |
1396 | qemu_vfree(acb->orig_buf); | |
585f8587 | 1397 | } |
f141eafe AL |
1398 | acb->common.cb(acb->common.opaque, ret); |
1399 | qemu_aio_release(acb); | |
585f8587 FB |
1400 | } |
1401 | ||
ce1a14dc | 1402 | static QCowAIOCB *qcow_aio_setup(BlockDriverState *bs, |
f141eafe AL |
1403 | int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, |
1404 | BlockDriverCompletionFunc *cb, void *opaque, int is_write) | |
585f8587 | 1405 | { |
ce1a14dc PB |
1406 | QCowAIOCB *acb; |
1407 | ||
1408 | acb = qemu_aio_get(bs, cb, opaque); | |
1409 | if (!acb) | |
1410 | return NULL; | |
1411 | acb->hd_aiocb = NULL; | |
1412 | acb->sector_num = sector_num; | |
f141eafe AL |
1413 | acb->qiov = qiov; |
1414 | if (qiov->niov > 1) { | |
e268ca52 | 1415 | acb->buf = acb->orig_buf = qemu_blockalign(bs, qiov->size); |
f141eafe AL |
1416 | if (is_write) |
1417 | qemu_iovec_to_buffer(qiov, acb->buf); | |
3f4cb3d3 BS |
1418 | } else { |
1419 | acb->buf = (uint8_t *)qiov->iov->iov_base; | |
1420 | } | |
ce1a14dc PB |
1421 | acb->nb_sectors = nb_sectors; |
1422 | acb->n = 0; | |
1423 | acb->cluster_offset = 0; | |
e976c6a1 | 1424 | acb->l2meta.nb_clusters = 0; |
ce1a14dc PB |
1425 | return acb; |
1426 | } | |
1427 | ||
f141eafe AL |
1428 | static BlockDriverAIOCB *qcow_aio_readv(BlockDriverState *bs, |
1429 | int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, | |
ce1a14dc PB |
1430 | BlockDriverCompletionFunc *cb, void *opaque) |
1431 | { | |
1432 | QCowAIOCB *acb; | |
1433 | ||
f141eafe | 1434 | acb = qcow_aio_setup(bs, sector_num, qiov, nb_sectors, cb, opaque, 0); |
ce1a14dc PB |
1435 | if (!acb) |
1436 | return NULL; | |
585f8587 FB |
1437 | |
1438 | qcow_aio_read_cb(acb, 0); | |
ce1a14dc | 1439 | return &acb->common; |
585f8587 FB |
1440 | } |
1441 | ||
1442 | static void qcow_aio_write_cb(void *opaque, int ret) | |
1443 | { | |
ce1a14dc PB |
1444 | QCowAIOCB *acb = opaque; |
1445 | BlockDriverState *bs = acb->common.bs; | |
585f8587 | 1446 | BDRVQcowState *s = bs->opaque; |
585f8587 | 1447 | int index_in_cluster; |
585f8587 | 1448 | const uint8_t *src_buf; |
095a9c58 | 1449 | int n_end; |
ce1a14dc PB |
1450 | |
1451 | acb->hd_aiocb = NULL; | |
1452 | ||
f141eafe AL |
1453 | if (ret < 0) |
1454 | goto done; | |
585f8587 | 1455 | |
e976c6a1 AL |
1456 | if (alloc_cluster_link_l2(bs, acb->cluster_offset, &acb->l2meta) < 0) { |
1457 | free_any_clusters(bs, acb->cluster_offset, acb->l2meta.nb_clusters); | |
f141eafe | 1458 | goto done; |
e976c6a1 AL |
1459 | } |
1460 | ||
ce1a14dc PB |
1461 | acb->nb_sectors -= acb->n; |
1462 | acb->sector_num += acb->n; | |
1463 | acb->buf += acb->n * 512; | |
585f8587 | 1464 | |
ce1a14dc | 1465 | if (acb->nb_sectors == 0) { |
585f8587 | 1466 | /* request completed */ |
f141eafe AL |
1467 | ret = 0; |
1468 | goto done; | |
585f8587 | 1469 | } |
3b46e624 | 1470 | |
ce1a14dc | 1471 | index_in_cluster = acb->sector_num & (s->cluster_sectors - 1); |
095a9c58 AL |
1472 | n_end = index_in_cluster + acb->nb_sectors; |
1473 | if (s->crypt_method && | |
1474 | n_end > QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors) | |
1475 | n_end = QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors; | |
1476 | ||
e976c6a1 | 1477 | acb->cluster_offset = alloc_cluster_offset(bs, acb->sector_num << 9, |
05203524 | 1478 | index_in_cluster, |
e976c6a1 AL |
1479 | n_end, &acb->n, &acb->l2meta); |
1480 | if (!acb->cluster_offset || (acb->cluster_offset & 511) != 0) { | |
585f8587 | 1481 | ret = -EIO; |
f141eafe | 1482 | goto done; |
585f8587 FB |
1483 | } |
1484 | if (s->crypt_method) { | |
ce1a14dc | 1485 | if (!acb->cluster_data) { |
095a9c58 AL |
1486 | acb->cluster_data = qemu_mallocz(QCOW_MAX_CRYPT_CLUSTERS * |
1487 | s->cluster_size); | |
585f8587 | 1488 | } |
5fafdf24 | 1489 | encrypt_sectors(s, acb->sector_num, acb->cluster_data, acb->buf, |
ce1a14dc PB |
1490 | acb->n, 1, &s->aes_encrypt_key); |
1491 | src_buf = acb->cluster_data; | |
585f8587 | 1492 | } else { |
ce1a14dc | 1493 | src_buf = acb->buf; |
585f8587 | 1494 | } |
c87c0672 AL |
1495 | acb->hd_iov.iov_base = (void *)src_buf; |
1496 | acb->hd_iov.iov_len = acb->n * 512; | |
1497 | qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1); | |
1498 | acb->hd_aiocb = bdrv_aio_writev(s->hd, | |
1499 | (acb->cluster_offset >> 9) + index_in_cluster, | |
1500 | &acb->hd_qiov, acb->n, | |
1501 | qcow_aio_write_cb, acb); | |
ce1a14dc | 1502 | if (acb->hd_aiocb == NULL) |
f141eafe AL |
1503 | goto done; |
1504 | ||
1505 | return; | |
1506 | ||
1507 | done: | |
1508 | if (acb->qiov->niov > 1) | |
1509 | qemu_vfree(acb->orig_buf); | |
1510 | acb->common.cb(acb->common.opaque, ret); | |
1511 | qemu_aio_release(acb); | |
585f8587 FB |
1512 | } |
1513 | ||
f141eafe AL |
1514 | static BlockDriverAIOCB *qcow_aio_writev(BlockDriverState *bs, |
1515 | int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, | |
ce1a14dc | 1516 | BlockDriverCompletionFunc *cb, void *opaque) |
585f8587 | 1517 | { |
585f8587 | 1518 | BDRVQcowState *s = bs->opaque; |
ce1a14dc | 1519 | QCowAIOCB *acb; |
3b46e624 | 1520 | |
585f8587 FB |
1521 | s->cluster_cache_offset = -1; /* disable compressed cache */ |
1522 | ||
f141eafe | 1523 | acb = qcow_aio_setup(bs, sector_num, qiov, nb_sectors, cb, opaque, 1); |
ce1a14dc PB |
1524 | if (!acb) |
1525 | return NULL; | |
3b46e624 | 1526 | |
585f8587 | 1527 | qcow_aio_write_cb(acb, 0); |
ce1a14dc | 1528 | return &acb->common; |
585f8587 FB |
1529 | } |
1530 | ||
ce1a14dc | 1531 | static void qcow_aio_cancel(BlockDriverAIOCB *blockacb) |
585f8587 | 1532 | { |
ce1a14dc PB |
1533 | QCowAIOCB *acb = (QCowAIOCB *)blockacb; |
1534 | if (acb->hd_aiocb) | |
1535 | bdrv_aio_cancel(acb->hd_aiocb); | |
1536 | qemu_aio_release(acb); | |
585f8587 FB |
1537 | } |
1538 | ||
1539 | static void qcow_close(BlockDriverState *bs) | |
1540 | { | |
1541 | BDRVQcowState *s = bs->opaque; | |
1542 | qemu_free(s->l1_table); | |
1543 | qemu_free(s->l2_cache); | |
1544 | qemu_free(s->cluster_cache); | |
1545 | qemu_free(s->cluster_data); | |
1546 | refcount_close(bs); | |
1547 | bdrv_delete(s->hd); | |
1548 | } | |
1549 | ||
1550 | /* XXX: use std qcow open function ? */ | |
1551 | typedef struct QCowCreateState { | |
1552 | int cluster_size; | |
1553 | int cluster_bits; | |
1554 | uint16_t *refcount_block; | |
1555 | uint64_t *refcount_table; | |
1556 | int64_t l1_table_offset; | |
1557 | int64_t refcount_table_offset; | |
1558 | int64_t refcount_block_offset; | |
1559 | } QCowCreateState; | |
1560 | ||
1561 | static void create_refcount_update(QCowCreateState *s, | |
1562 | int64_t offset, int64_t size) | |
1563 | { | |
1564 | int refcount; | |
1565 | int64_t start, last, cluster_offset; | |
1566 | uint16_t *p; | |
1567 | ||
1568 | start = offset & ~(s->cluster_size - 1); | |
1569 | last = (offset + size - 1) & ~(s->cluster_size - 1); | |
5fafdf24 | 1570 | for(cluster_offset = start; cluster_offset <= last; |
585f8587 FB |
1571 | cluster_offset += s->cluster_size) { |
1572 | p = &s->refcount_block[cluster_offset >> s->cluster_bits]; | |
1573 | refcount = be16_to_cpu(*p); | |
1574 | refcount++; | |
1575 | *p = cpu_to_be16(refcount); | |
1576 | } | |
1577 | } | |
1578 | ||
f965509c AL |
1579 | static int qcow_create2(const char *filename, int64_t total_size, |
1580 | const char *backing_file, const char *backing_format, | |
1581 | int flags) | |
585f8587 | 1582 | { |
f965509c | 1583 | |
585f8587 | 1584 | int fd, header_size, backing_filename_len, l1_size, i, shift, l2_bits; |
2d2431f0 | 1585 | int ref_clusters, backing_format_len = 0; |
585f8587 FB |
1586 | QCowHeader header; |
1587 | uint64_t tmp, offset; | |
1588 | QCowCreateState s1, *s = &s1; | |
f965509c AL |
1589 | QCowExtension ext_bf = {0, 0}; |
1590 | ||
3b46e624 | 1591 | |
585f8587 FB |
1592 | memset(s, 0, sizeof(*s)); |
1593 | ||
1594 | fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, 0644); | |
1595 | if (fd < 0) | |
1596 | return -1; | |
1597 | memset(&header, 0, sizeof(header)); | |
1598 | header.magic = cpu_to_be32(QCOW_MAGIC); | |
1599 | header.version = cpu_to_be32(QCOW_VERSION); | |
1600 | header.size = cpu_to_be64(total_size * 512); | |
1601 | header_size = sizeof(header); | |
1602 | backing_filename_len = 0; | |
1603 | if (backing_file) { | |
f965509c AL |
1604 | if (backing_format) { |
1605 | ext_bf.magic = QCOW_EXT_MAGIC_BACKING_FORMAT; | |
1606 | backing_format_len = strlen(backing_format); | |
1607 | ext_bf.len = (backing_format_len + 7) & ~7; | |
1608 | header_size += ((sizeof(ext_bf) + ext_bf.len + 7) & ~7); | |
1609 | } | |
585f8587 FB |
1610 | header.backing_file_offset = cpu_to_be64(header_size); |
1611 | backing_filename_len = strlen(backing_file); | |
1612 | header.backing_file_size = cpu_to_be32(backing_filename_len); | |
1613 | header_size += backing_filename_len; | |
1614 | } | |
1615 | s->cluster_bits = 12; /* 4 KB clusters */ | |
1616 | s->cluster_size = 1 << s->cluster_bits; | |
1617 | header.cluster_bits = cpu_to_be32(s->cluster_bits); | |
1618 | header_size = (header_size + 7) & ~7; | |
ec36ba14 | 1619 | if (flags & BLOCK_FLAG_ENCRYPT) { |
585f8587 FB |
1620 | header.crypt_method = cpu_to_be32(QCOW_CRYPT_AES); |
1621 | } else { | |
1622 | header.crypt_method = cpu_to_be32(QCOW_CRYPT_NONE); | |
1623 | } | |
1624 | l2_bits = s->cluster_bits - 3; | |
1625 | shift = s->cluster_bits + l2_bits; | |
1626 | l1_size = (((total_size * 512) + (1LL << shift) - 1) >> shift); | |
1627 | offset = align_offset(header_size, s->cluster_size); | |
1628 | s->l1_table_offset = offset; | |
1629 | header.l1_table_offset = cpu_to_be64(s->l1_table_offset); | |
1630 | header.l1_size = cpu_to_be32(l1_size); | |
15e6690a | 1631 | offset += align_offset(l1_size * sizeof(uint64_t), s->cluster_size); |
585f8587 FB |
1632 | |
1633 | s->refcount_table = qemu_mallocz(s->cluster_size); | |
3b46e624 | 1634 | |
585f8587 FB |
1635 | s->refcount_table_offset = offset; |
1636 | header.refcount_table_offset = cpu_to_be64(offset); | |
1637 | header.refcount_table_clusters = cpu_to_be32(1); | |
1638 | offset += s->cluster_size; | |
585f8587 | 1639 | s->refcount_block_offset = offset; |
2d2431f0 AL |
1640 | |
1641 | /* count how many refcount blocks needed */ | |
1642 | tmp = offset >> s->cluster_bits; | |
1643 | ref_clusters = (tmp >> (s->cluster_bits - REFCOUNT_SHIFT)) + 1; | |
1644 | for (i=0; i < ref_clusters; i++) { | |
1645 | s->refcount_table[i] = cpu_to_be64(offset); | |
1646 | offset += s->cluster_size; | |
1647 | } | |
1648 | ||
1649 | s->refcount_block = qemu_mallocz(ref_clusters * s->cluster_size); | |
585f8587 FB |
1650 | |
1651 | /* update refcounts */ | |
1652 | create_refcount_update(s, 0, header_size); | |
15e6690a | 1653 | create_refcount_update(s, s->l1_table_offset, l1_size * sizeof(uint64_t)); |
585f8587 | 1654 | create_refcount_update(s, s->refcount_table_offset, s->cluster_size); |
2d2431f0 | 1655 | create_refcount_update(s, s->refcount_block_offset, ref_clusters * s->cluster_size); |
3b46e624 | 1656 | |
585f8587 FB |
1657 | /* write all the data */ |
1658 | write(fd, &header, sizeof(header)); | |
1659 | if (backing_file) { | |
f965509c AL |
1660 | if (backing_format_len) { |
1661 | char zero[16]; | |
1662 | int d = ext_bf.len - backing_format_len; | |
1663 | ||
1664 | memset(zero, 0, sizeof(zero)); | |
1665 | cpu_to_be32s(&ext_bf.magic); | |
1666 | cpu_to_be32s(&ext_bf.len); | |
1667 | write(fd, &ext_bf, sizeof(ext_bf)); | |
1668 | write(fd, backing_format, backing_format_len); | |
1669 | if (d>0) { | |
1670 | write(fd, zero, d); | |
1671 | } | |
1672 | } | |
585f8587 FB |
1673 | write(fd, backing_file, backing_filename_len); |
1674 | } | |
1675 | lseek(fd, s->l1_table_offset, SEEK_SET); | |
1676 | tmp = 0; | |
1677 | for(i = 0;i < l1_size; i++) { | |
1678 | write(fd, &tmp, sizeof(tmp)); | |
1679 | } | |
1680 | lseek(fd, s->refcount_table_offset, SEEK_SET); | |
1681 | write(fd, s->refcount_table, s->cluster_size); | |
3b46e624 | 1682 | |
585f8587 | 1683 | lseek(fd, s->refcount_block_offset, SEEK_SET); |
2d2431f0 | 1684 | write(fd, s->refcount_block, ref_clusters * s->cluster_size); |
585f8587 FB |
1685 | |
1686 | qemu_free(s->refcount_table); | |
1687 | qemu_free(s->refcount_block); | |
1688 | close(fd); | |
1689 | return 0; | |
585f8587 FB |
1690 | } |
1691 | ||
f965509c AL |
1692 | static int qcow_create(const char *filename, int64_t total_size, |
1693 | const char *backing_file, int flags) | |
1694 | { | |
1695 | return qcow_create2(filename, total_size, backing_file, NULL, flags); | |
1696 | } | |
1697 | ||
585f8587 FB |
1698 | static int qcow_make_empty(BlockDriverState *bs) |
1699 | { | |
1700 | #if 0 | |
1701 | /* XXX: not correct */ | |
1702 | BDRVQcowState *s = bs->opaque; | |
1703 | uint32_t l1_length = s->l1_size * sizeof(uint64_t); | |
1704 | int ret; | |
1705 | ||
1706 | memset(s->l1_table, 0, l1_length); | |
1707 | if (bdrv_pwrite(s->hd, s->l1_table_offset, s->l1_table, l1_length) < 0) | |
ac674887 | 1708 | return -1; |
585f8587 FB |
1709 | ret = bdrv_truncate(s->hd, s->l1_table_offset + l1_length); |
1710 | if (ret < 0) | |
1711 | return ret; | |
3b46e624 | 1712 | |
585f8587 FB |
1713 | l2_cache_reset(bs); |
1714 | #endif | |
1715 | return 0; | |
1716 | } | |
1717 | ||
1718 | /* XXX: put compressed sectors first, then all the cluster aligned | |
1719 | tables to avoid losing bytes in alignment */ | |
5fafdf24 | 1720 | static int qcow_write_compressed(BlockDriverState *bs, int64_t sector_num, |
585f8587 FB |
1721 | const uint8_t *buf, int nb_sectors) |
1722 | { | |
1723 | BDRVQcowState *s = bs->opaque; | |
1724 | z_stream strm; | |
1725 | int ret, out_len; | |
1726 | uint8_t *out_buf; | |
1727 | uint64_t cluster_offset; | |
1728 | ||
1729 | if (nb_sectors == 0) { | |
1730 | /* align end of file to a sector boundary to ease reading with | |
1731 | sector based I/Os */ | |
1732 | cluster_offset = bdrv_getlength(s->hd); | |
1733 | cluster_offset = (cluster_offset + 511) & ~511; | |
1734 | bdrv_truncate(s->hd, cluster_offset); | |
1735 | return 0; | |
1736 | } | |
1737 | ||
1738 | if (nb_sectors != s->cluster_sectors) | |
1739 | return -EINVAL; | |
1740 | ||
1741 | out_buf = qemu_malloc(s->cluster_size + (s->cluster_size / 1000) + 128); | |
585f8587 FB |
1742 | |
1743 | /* best compression, small window, no zlib header */ | |
1744 | memset(&strm, 0, sizeof(strm)); | |
1745 | ret = deflateInit2(&strm, Z_DEFAULT_COMPRESSION, | |
5fafdf24 | 1746 | Z_DEFLATED, -12, |
585f8587 FB |
1747 | 9, Z_DEFAULT_STRATEGY); |
1748 | if (ret != 0) { | |
1749 | qemu_free(out_buf); | |
1750 | return -1; | |
1751 | } | |
1752 | ||
1753 | strm.avail_in = s->cluster_size; | |
1754 | strm.next_in = (uint8_t *)buf; | |
1755 | strm.avail_out = s->cluster_size; | |
1756 | strm.next_out = out_buf; | |
1757 | ||
1758 | ret = deflate(&strm, Z_FINISH); | |
1759 | if (ret != Z_STREAM_END && ret != Z_OK) { | |
1760 | qemu_free(out_buf); | |
1761 | deflateEnd(&strm); | |
1762 | return -1; | |
1763 | } | |
1764 | out_len = strm.next_out - out_buf; | |
1765 | ||
1766 | deflateEnd(&strm); | |
1767 | ||
1768 | if (ret != Z_STREAM_END || out_len >= s->cluster_size) { | |
1769 | /* could not compress: write normal cluster */ | |
1770 | qcow_write(bs, sector_num, buf, s->cluster_sectors); | |
1771 | } else { | |
52d893ec AL |
1772 | cluster_offset = alloc_compressed_cluster_offset(bs, sector_num << 9, |
1773 | out_len); | |
1774 | if (!cluster_offset) | |
1775 | return -1; | |
585f8587 FB |
1776 | cluster_offset &= s->cluster_offset_mask; |
1777 | if (bdrv_pwrite(s->hd, cluster_offset, out_buf, out_len) != out_len) { | |
1778 | qemu_free(out_buf); | |
1779 | return -1; | |
1780 | } | |
1781 | } | |
3b46e624 | 1782 | |
585f8587 FB |
1783 | qemu_free(out_buf); |
1784 | return 0; | |
1785 | } | |
1786 | ||
1787 | static void qcow_flush(BlockDriverState *bs) | |
1788 | { | |
1789 | BDRVQcowState *s = bs->opaque; | |
1790 | bdrv_flush(s->hd); | |
1791 | } | |
1792 | ||
1793 | static int qcow_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) | |
1794 | { | |
1795 | BDRVQcowState *s = bs->opaque; | |
1796 | bdi->cluster_size = s->cluster_size; | |
5fafdf24 | 1797 | bdi->vm_state_offset = (int64_t)s->l1_vm_state_index << |
585f8587 FB |
1798 | (s->cluster_bits + s->l2_bits); |
1799 | return 0; | |
1800 | } | |
1801 | ||
1802 | /*********************************************************/ | |
1803 | /* snapshot support */ | |
1804 | ||
1805 | /* update the refcounts of snapshots and the copied flag */ | |
5fafdf24 | 1806 | static int update_snapshot_refcount(BlockDriverState *bs, |
585f8587 FB |
1807 | int64_t l1_table_offset, |
1808 | int l1_size, | |
1809 | int addend) | |
1810 | { | |
1811 | BDRVQcowState *s = bs->opaque; | |
1812 | uint64_t *l1_table, *l2_table, l2_offset, offset, l1_size2, l1_allocated; | |
1813 | int64_t old_offset, old_l2_offset; | |
1814 | int l2_size, i, j, l1_modified, l2_modified, nb_csectors, refcount; | |
3b46e624 | 1815 | |
585f8587 FB |
1816 | l2_cache_reset(bs); |
1817 | ||
1818 | l2_table = NULL; | |
1819 | l1_table = NULL; | |
1820 | l1_size2 = l1_size * sizeof(uint64_t); | |
1821 | l1_allocated = 0; | |
1822 | if (l1_table_offset != s->l1_table_offset) { | |
1823 | l1_table = qemu_malloc(l1_size2); | |
585f8587 | 1824 | l1_allocated = 1; |
5fafdf24 | 1825 | if (bdrv_pread(s->hd, l1_table_offset, |
585f8587 FB |
1826 | l1_table, l1_size2) != l1_size2) |
1827 | goto fail; | |
1828 | for(i = 0;i < l1_size; i++) | |
1829 | be64_to_cpus(&l1_table[i]); | |
1830 | } else { | |
1831 | assert(l1_size == s->l1_size); | |
1832 | l1_table = s->l1_table; | |
1833 | l1_allocated = 0; | |
1834 | } | |
3b46e624 | 1835 | |
585f8587 FB |
1836 | l2_size = s->l2_size * sizeof(uint64_t); |
1837 | l2_table = qemu_malloc(l2_size); | |
585f8587 FB |
1838 | l1_modified = 0; |
1839 | for(i = 0; i < l1_size; i++) { | |
1840 | l2_offset = l1_table[i]; | |
1841 | if (l2_offset) { | |
1842 | old_l2_offset = l2_offset; | |
1843 | l2_offset &= ~QCOW_OFLAG_COPIED; | |
1844 | l2_modified = 0; | |
1845 | if (bdrv_pread(s->hd, l2_offset, l2_table, l2_size) != l2_size) | |
1846 | goto fail; | |
1847 | for(j = 0; j < s->l2_size; j++) { | |
1848 | offset = be64_to_cpu(l2_table[j]); | |
1849 | if (offset != 0) { | |
1850 | old_offset = offset; | |
1851 | offset &= ~QCOW_OFLAG_COPIED; | |
1852 | if (offset & QCOW_OFLAG_COMPRESSED) { | |
5fafdf24 | 1853 | nb_csectors = ((offset >> s->csize_shift) & |
585f8587 FB |
1854 | s->csize_mask) + 1; |
1855 | if (addend != 0) | |
1856 | update_refcount(bs, (offset & s->cluster_offset_mask) & ~511, | |
1857 | nb_csectors * 512, addend); | |
1858 | /* compressed clusters are never modified */ | |
5fafdf24 | 1859 | refcount = 2; |
585f8587 FB |
1860 | } else { |
1861 | if (addend != 0) { | |
1862 | refcount = update_cluster_refcount(bs, offset >> s->cluster_bits, addend); | |
1863 | } else { | |
1864 | refcount = get_refcount(bs, offset >> s->cluster_bits); | |
1865 | } | |
1866 | } | |
1867 | ||
1868 | if (refcount == 1) { | |
1869 | offset |= QCOW_OFLAG_COPIED; | |
1870 | } | |
1871 | if (offset != old_offset) { | |
1872 | l2_table[j] = cpu_to_be64(offset); | |
1873 | l2_modified = 1; | |
1874 | } | |
1875 | } | |
1876 | } | |
1877 | if (l2_modified) { | |
5fafdf24 | 1878 | if (bdrv_pwrite(s->hd, |
585f8587 FB |
1879 | l2_offset, l2_table, l2_size) != l2_size) |
1880 | goto fail; | |
1881 | } | |
1882 | ||
1883 | if (addend != 0) { | |
1884 | refcount = update_cluster_refcount(bs, l2_offset >> s->cluster_bits, addend); | |
1885 | } else { | |
1886 | refcount = get_refcount(bs, l2_offset >> s->cluster_bits); | |
1887 | } | |
1888 | if (refcount == 1) { | |
1889 | l2_offset |= QCOW_OFLAG_COPIED; | |
1890 | } | |
1891 | if (l2_offset != old_l2_offset) { | |
1892 | l1_table[i] = l2_offset; | |
1893 | l1_modified = 1; | |
1894 | } | |
1895 | } | |
1896 | } | |
1897 | if (l1_modified) { | |
1898 | for(i = 0; i < l1_size; i++) | |
1899 | cpu_to_be64s(&l1_table[i]); | |
5fafdf24 | 1900 | if (bdrv_pwrite(s->hd, l1_table_offset, l1_table, |
585f8587 FB |
1901 | l1_size2) != l1_size2) |
1902 | goto fail; | |
1903 | for(i = 0; i < l1_size; i++) | |
1904 | be64_to_cpus(&l1_table[i]); | |
1905 | } | |
1906 | if (l1_allocated) | |
1907 | qemu_free(l1_table); | |
1908 | qemu_free(l2_table); | |
1909 | return 0; | |
1910 | fail: | |
1911 | if (l1_allocated) | |
1912 | qemu_free(l1_table); | |
1913 | qemu_free(l2_table); | |
1914 | return -EIO; | |
1915 | } | |
1916 | ||
1917 | static void qcow_free_snapshots(BlockDriverState *bs) | |
1918 | { | |
1919 | BDRVQcowState *s = bs->opaque; | |
1920 | int i; | |
1921 | ||
1922 | for(i = 0; i < s->nb_snapshots; i++) { | |
1923 | qemu_free(s->snapshots[i].name); | |
1924 | qemu_free(s->snapshots[i].id_str); | |
1925 | } | |
1926 | qemu_free(s->snapshots); | |
1927 | s->snapshots = NULL; | |
1928 | s->nb_snapshots = 0; | |
1929 | } | |
1930 | ||
1931 | static int qcow_read_snapshots(BlockDriverState *bs) | |
1932 | { | |
1933 | BDRVQcowState *s = bs->opaque; | |
1934 | QCowSnapshotHeader h; | |
1935 | QCowSnapshot *sn; | |
1936 | int i, id_str_size, name_size; | |
1937 | int64_t offset; | |
1938 | uint32_t extra_data_size; | |
1939 | ||
63c75dcd | 1940 | if (!s->nb_snapshots) { |
1941 | s->snapshots = NULL; | |
1942 | s->snapshots_size = 0; | |
1943 | return 0; | |
1944 | } | |
1945 | ||
585f8587 FB |
1946 | offset = s->snapshots_offset; |
1947 | s->snapshots = qemu_mallocz(s->nb_snapshots * sizeof(QCowSnapshot)); | |
585f8587 FB |
1948 | for(i = 0; i < s->nb_snapshots; i++) { |
1949 | offset = align_offset(offset, 8); | |
1950 | if (bdrv_pread(s->hd, offset, &h, sizeof(h)) != sizeof(h)) | |
1951 | goto fail; | |
1952 | offset += sizeof(h); | |
1953 | sn = s->snapshots + i; | |
1954 | sn->l1_table_offset = be64_to_cpu(h.l1_table_offset); | |
1955 | sn->l1_size = be32_to_cpu(h.l1_size); | |
1956 | sn->vm_state_size = be32_to_cpu(h.vm_state_size); | |
1957 | sn->date_sec = be32_to_cpu(h.date_sec); | |
1958 | sn->date_nsec = be32_to_cpu(h.date_nsec); | |
1959 | sn->vm_clock_nsec = be64_to_cpu(h.vm_clock_nsec); | |
1960 | extra_data_size = be32_to_cpu(h.extra_data_size); | |
1961 | ||
1962 | id_str_size = be16_to_cpu(h.id_str_size); | |
1963 | name_size = be16_to_cpu(h.name_size); | |
1964 | ||
1965 | offset += extra_data_size; | |
1966 | ||
1967 | sn->id_str = qemu_malloc(id_str_size + 1); | |
585f8587 FB |
1968 | if (bdrv_pread(s->hd, offset, sn->id_str, id_str_size) != id_str_size) |
1969 | goto fail; | |
1970 | offset += id_str_size; | |
1971 | sn->id_str[id_str_size] = '\0'; | |
1972 | ||
1973 | sn->name = qemu_malloc(name_size + 1); | |
585f8587 FB |
1974 | if (bdrv_pread(s->hd, offset, sn->name, name_size) != name_size) |
1975 | goto fail; | |
1976 | offset += name_size; | |
1977 | sn->name[name_size] = '\0'; | |
1978 | } | |
1979 | s->snapshots_size = offset - s->snapshots_offset; | |
1980 | return 0; | |
1981 | fail: | |
1982 | qcow_free_snapshots(bs); | |
1983 | return -1; | |
1984 | } | |
1985 | ||
1986 | /* add at the end of the file a new list of snapshots */ | |
1987 | static int qcow_write_snapshots(BlockDriverState *bs) | |
1988 | { | |
1989 | BDRVQcowState *s = bs->opaque; | |
1990 | QCowSnapshot *sn; | |
1991 | QCowSnapshotHeader h; | |
1992 | int i, name_size, id_str_size, snapshots_size; | |
1993 | uint64_t data64; | |
1994 | uint32_t data32; | |
1995 | int64_t offset, snapshots_offset; | |
1996 | ||
1997 | /* compute the size of the snapshots */ | |
1998 | offset = 0; | |
1999 | for(i = 0; i < s->nb_snapshots; i++) { | |
2000 | sn = s->snapshots + i; | |
2001 | offset = align_offset(offset, 8); | |
2002 | offset += sizeof(h); | |
2003 | offset += strlen(sn->id_str); | |
2004 | offset += strlen(sn->name); | |
2005 | } | |
2006 | snapshots_size = offset; | |
2007 | ||
2008 | snapshots_offset = alloc_clusters(bs, snapshots_size); | |
2009 | offset = snapshots_offset; | |
3b46e624 | 2010 | |
585f8587 FB |
2011 | for(i = 0; i < s->nb_snapshots; i++) { |
2012 | sn = s->snapshots + i; | |
2013 | memset(&h, 0, sizeof(h)); | |
2014 | h.l1_table_offset = cpu_to_be64(sn->l1_table_offset); | |
2015 | h.l1_size = cpu_to_be32(sn->l1_size); | |
2016 | h.vm_state_size = cpu_to_be32(sn->vm_state_size); | |
2017 | h.date_sec = cpu_to_be32(sn->date_sec); | |
2018 | h.date_nsec = cpu_to_be32(sn->date_nsec); | |
2019 | h.vm_clock_nsec = cpu_to_be64(sn->vm_clock_nsec); | |
3b46e624 | 2020 | |
585f8587 FB |
2021 | id_str_size = strlen(sn->id_str); |
2022 | name_size = strlen(sn->name); | |
2023 | h.id_str_size = cpu_to_be16(id_str_size); | |
2024 | h.name_size = cpu_to_be16(name_size); | |
2025 | offset = align_offset(offset, 8); | |
2026 | if (bdrv_pwrite(s->hd, offset, &h, sizeof(h)) != sizeof(h)) | |
2027 | goto fail; | |
2028 | offset += sizeof(h); | |
2029 | if (bdrv_pwrite(s->hd, offset, sn->id_str, id_str_size) != id_str_size) | |
2030 | goto fail; | |
2031 | offset += id_str_size; | |
2032 | if (bdrv_pwrite(s->hd, offset, sn->name, name_size) != name_size) | |
2033 | goto fail; | |
2034 | offset += name_size; | |
2035 | } | |
2036 | ||
2037 | /* update the various header fields */ | |
2038 | data64 = cpu_to_be64(snapshots_offset); | |
2039 | if (bdrv_pwrite(s->hd, offsetof(QCowHeader, snapshots_offset), | |
2040 | &data64, sizeof(data64)) != sizeof(data64)) | |
2041 | goto fail; | |
2042 | data32 = cpu_to_be32(s->nb_snapshots); | |
2043 | if (bdrv_pwrite(s->hd, offsetof(QCowHeader, nb_snapshots), | |
2044 | &data32, sizeof(data32)) != sizeof(data32)) | |
2045 | goto fail; | |
2046 | ||
2047 | /* free the old snapshot table */ | |
2048 | free_clusters(bs, s->snapshots_offset, s->snapshots_size); | |
2049 | s->snapshots_offset = snapshots_offset; | |
2050 | s->snapshots_size = snapshots_size; | |
2051 | return 0; | |
2052 | fail: | |
2053 | return -1; | |
2054 | } | |
2055 | ||
2056 | static void find_new_snapshot_id(BlockDriverState *bs, | |
2057 | char *id_str, int id_str_size) | |
2058 | { | |
2059 | BDRVQcowState *s = bs->opaque; | |
2060 | QCowSnapshot *sn; | |
2061 | int i, id, id_max = 0; | |
2062 | ||
2063 | for(i = 0; i < s->nb_snapshots; i++) { | |
2064 | sn = s->snapshots + i; | |
2065 | id = strtoul(sn->id_str, NULL, 10); | |
2066 | if (id > id_max) | |
2067 | id_max = id; | |
2068 | } | |
2069 | snprintf(id_str, id_str_size, "%d", id_max + 1); | |
2070 | } | |
2071 | ||
2072 | static int find_snapshot_by_id(BlockDriverState *bs, const char *id_str) | |
2073 | { | |
2074 | BDRVQcowState *s = bs->opaque; | |
2075 | int i; | |
2076 | ||
2077 | for(i = 0; i < s->nb_snapshots; i++) { | |
2078 | if (!strcmp(s->snapshots[i].id_str, id_str)) | |
2079 | return i; | |
2080 | } | |
2081 | return -1; | |
2082 | } | |
2083 | ||
2084 | static int find_snapshot_by_id_or_name(BlockDriverState *bs, const char *name) | |
2085 | { | |
2086 | BDRVQcowState *s = bs->opaque; | |
2087 | int i, ret; | |
3b46e624 | 2088 | |
585f8587 FB |
2089 | ret = find_snapshot_by_id(bs, name); |
2090 | if (ret >= 0) | |
2091 | return ret; | |
2092 | for(i = 0; i < s->nb_snapshots; i++) { | |
2093 | if (!strcmp(s->snapshots[i].name, name)) | |
2094 | return i; | |
2095 | } | |
2096 | return -1; | |
2097 | } | |
2098 | ||
2099 | /* if no id is provided, a new one is constructed */ | |
5fafdf24 | 2100 | static int qcow_snapshot_create(BlockDriverState *bs, |
585f8587 FB |
2101 | QEMUSnapshotInfo *sn_info) |
2102 | { | |
2103 | BDRVQcowState *s = bs->opaque; | |
2104 | QCowSnapshot *snapshots1, sn1, *sn = &sn1; | |
2105 | int i, ret; | |
2106 | uint64_t *l1_table = NULL; | |
3b46e624 | 2107 | |
585f8587 FB |
2108 | memset(sn, 0, sizeof(*sn)); |
2109 | ||
2110 | if (sn_info->id_str[0] == '\0') { | |
2111 | /* compute a new id */ | |
2112 | find_new_snapshot_id(bs, sn_info->id_str, sizeof(sn_info->id_str)); | |
2113 | } | |
2114 | ||
2115 | /* check that the ID is unique */ | |
2116 | if (find_snapshot_by_id(bs, sn_info->id_str) >= 0) | |
2117 | return -ENOENT; | |
2118 | ||
2119 | sn->id_str = qemu_strdup(sn_info->id_str); | |
2120 | if (!sn->id_str) | |
2121 | goto fail; | |
2122 | sn->name = qemu_strdup(sn_info->name); | |
2123 | if (!sn->name) | |
2124 | goto fail; | |
2125 | sn->vm_state_size = sn_info->vm_state_size; | |
2126 | sn->date_sec = sn_info->date_sec; | |
2127 | sn->date_nsec = sn_info->date_nsec; | |
2128 | sn->vm_clock_nsec = sn_info->vm_clock_nsec; | |
2129 | ||
2130 | ret = update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 1); | |
2131 | if (ret < 0) | |
2132 | goto fail; | |
2133 | ||
2134 | /* create the L1 table of the snapshot */ | |
2135 | sn->l1_table_offset = alloc_clusters(bs, s->l1_size * sizeof(uint64_t)); | |
2136 | sn->l1_size = s->l1_size; | |
2137 | ||
2138 | l1_table = qemu_malloc(s->l1_size * sizeof(uint64_t)); | |
585f8587 FB |
2139 | for(i = 0; i < s->l1_size; i++) { |
2140 | l1_table[i] = cpu_to_be64(s->l1_table[i]); | |
2141 | } | |
2142 | if (bdrv_pwrite(s->hd, sn->l1_table_offset, | |
5fafdf24 | 2143 | l1_table, s->l1_size * sizeof(uint64_t)) != |
585f8587 FB |
2144 | (s->l1_size * sizeof(uint64_t))) |
2145 | goto fail; | |
2146 | qemu_free(l1_table); | |
2147 | l1_table = NULL; | |
2148 | ||
2149 | snapshots1 = qemu_malloc((s->nb_snapshots + 1) * sizeof(QCowSnapshot)); | |
63c75dcd | 2150 | if (s->snapshots) { |
2151 | memcpy(snapshots1, s->snapshots, s->nb_snapshots * sizeof(QCowSnapshot)); | |
2152 | qemu_free(s->snapshots); | |
2153 | } | |
585f8587 FB |
2154 | s->snapshots = snapshots1; |
2155 | s->snapshots[s->nb_snapshots++] = *sn; | |
2156 | ||
2157 | if (qcow_write_snapshots(bs) < 0) | |
2158 | goto fail; | |
2159 | #ifdef DEBUG_ALLOC | |
2160 | check_refcounts(bs); | |
2161 | #endif | |
2162 | return 0; | |
2163 | fail: | |
2164 | qemu_free(sn->name); | |
2165 | qemu_free(l1_table); | |
2166 | return -1; | |
2167 | } | |
2168 | ||
2169 | /* copy the snapshot 'snapshot_name' into the current disk image */ | |
5fafdf24 | 2170 | static int qcow_snapshot_goto(BlockDriverState *bs, |
585f8587 FB |
2171 | const char *snapshot_id) |
2172 | { | |
2173 | BDRVQcowState *s = bs->opaque; | |
2174 | QCowSnapshot *sn; | |
2175 | int i, snapshot_index, l1_size2; | |
2176 | ||
2177 | snapshot_index = find_snapshot_by_id_or_name(bs, snapshot_id); | |
2178 | if (snapshot_index < 0) | |
2179 | return -ENOENT; | |
2180 | sn = &s->snapshots[snapshot_index]; | |
2181 | ||
2182 | if (update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, -1) < 0) | |
2183 | goto fail; | |
2184 | ||
2185 | if (grow_l1_table(bs, sn->l1_size) < 0) | |
2186 | goto fail; | |
2187 | ||
2188 | s->l1_size = sn->l1_size; | |
2189 | l1_size2 = s->l1_size * sizeof(uint64_t); | |
2190 | /* copy the snapshot l1 table to the current l1 table */ | |
5fafdf24 | 2191 | if (bdrv_pread(s->hd, sn->l1_table_offset, |
585f8587 FB |
2192 | s->l1_table, l1_size2) != l1_size2) |
2193 | goto fail; | |
2194 | if (bdrv_pwrite(s->hd, s->l1_table_offset, | |
2195 | s->l1_table, l1_size2) != l1_size2) | |
2196 | goto fail; | |
2197 | for(i = 0;i < s->l1_size; i++) { | |
2198 | be64_to_cpus(&s->l1_table[i]); | |
2199 | } | |
2200 | ||
2201 | if (update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 1) < 0) | |
2202 | goto fail; | |
2203 | ||
2204 | #ifdef DEBUG_ALLOC | |
2205 | check_refcounts(bs); | |
2206 | #endif | |
2207 | return 0; | |
2208 | fail: | |
2209 | return -EIO; | |
2210 | } | |
2211 | ||
2212 | static int qcow_snapshot_delete(BlockDriverState *bs, const char *snapshot_id) | |
2213 | { | |
2214 | BDRVQcowState *s = bs->opaque; | |
2215 | QCowSnapshot *sn; | |
2216 | int snapshot_index, ret; | |
3b46e624 | 2217 | |
585f8587 FB |
2218 | snapshot_index = find_snapshot_by_id_or_name(bs, snapshot_id); |
2219 | if (snapshot_index < 0) | |
2220 | return -ENOENT; | |
2221 | sn = &s->snapshots[snapshot_index]; | |
2222 | ||
2223 | ret = update_snapshot_refcount(bs, sn->l1_table_offset, sn->l1_size, -1); | |
2224 | if (ret < 0) | |
2225 | return ret; | |
2226 | /* must update the copied flag on the current cluster offsets */ | |
2227 | ret = update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 0); | |
2228 | if (ret < 0) | |
2229 | return ret; | |
2230 | free_clusters(bs, sn->l1_table_offset, sn->l1_size * sizeof(uint64_t)); | |
2231 | ||
2232 | qemu_free(sn->id_str); | |
2233 | qemu_free(sn->name); | |
2234 | memmove(sn, sn + 1, (s->nb_snapshots - snapshot_index - 1) * sizeof(*sn)); | |
2235 | s->nb_snapshots--; | |
2236 | ret = qcow_write_snapshots(bs); | |
2237 | if (ret < 0) { | |
2238 | /* XXX: restore snapshot if error ? */ | |
2239 | return ret; | |
2240 | } | |
2241 | #ifdef DEBUG_ALLOC | |
2242 | check_refcounts(bs); | |
2243 | #endif | |
2244 | return 0; | |
2245 | } | |
2246 | ||
5fafdf24 | 2247 | static int qcow_snapshot_list(BlockDriverState *bs, |
585f8587 FB |
2248 | QEMUSnapshotInfo **psn_tab) |
2249 | { | |
2250 | BDRVQcowState *s = bs->opaque; | |
2251 | QEMUSnapshotInfo *sn_tab, *sn_info; | |
2252 | QCowSnapshot *sn; | |
2253 | int i; | |
2254 | ||
2255 | sn_tab = qemu_mallocz(s->nb_snapshots * sizeof(QEMUSnapshotInfo)); | |
585f8587 FB |
2256 | for(i = 0; i < s->nb_snapshots; i++) { |
2257 | sn_info = sn_tab + i; | |
2258 | sn = s->snapshots + i; | |
2259 | pstrcpy(sn_info->id_str, sizeof(sn_info->id_str), | |
2260 | sn->id_str); | |
2261 | pstrcpy(sn_info->name, sizeof(sn_info->name), | |
2262 | sn->name); | |
2263 | sn_info->vm_state_size = sn->vm_state_size; | |
2264 | sn_info->date_sec = sn->date_sec; | |
2265 | sn_info->date_nsec = sn->date_nsec; | |
2266 | sn_info->vm_clock_nsec = sn->vm_clock_nsec; | |
2267 | } | |
2268 | *psn_tab = sn_tab; | |
2269 | return s->nb_snapshots; | |
585f8587 FB |
2270 | } |
2271 | ||
2272 | /*********************************************************/ | |
2273 | /* refcount handling */ | |
2274 | ||
2275 | static int refcount_init(BlockDriverState *bs) | |
2276 | { | |
2277 | BDRVQcowState *s = bs->opaque; | |
2278 | int ret, refcount_table_size2, i; | |
3b46e624 | 2279 | |
585f8587 | 2280 | s->refcount_block_cache = qemu_malloc(s->cluster_size); |
585f8587 FB |
2281 | refcount_table_size2 = s->refcount_table_size * sizeof(uint64_t); |
2282 | s->refcount_table = qemu_malloc(refcount_table_size2); | |
585f8587 FB |
2283 | if (s->refcount_table_size > 0) { |
2284 | ret = bdrv_pread(s->hd, s->refcount_table_offset, | |
2285 | s->refcount_table, refcount_table_size2); | |
2286 | if (ret != refcount_table_size2) | |
2287 | goto fail; | |
2288 | for(i = 0; i < s->refcount_table_size; i++) | |
2289 | be64_to_cpus(&s->refcount_table[i]); | |
2290 | } | |
2291 | return 0; | |
2292 | fail: | |
2293 | return -ENOMEM; | |
2294 | } | |
2295 | ||
2296 | static void refcount_close(BlockDriverState *bs) | |
2297 | { | |
2298 | BDRVQcowState *s = bs->opaque; | |
2299 | qemu_free(s->refcount_block_cache); | |
2300 | qemu_free(s->refcount_table); | |
2301 | } | |
2302 | ||
2303 | ||
5fafdf24 | 2304 | static int load_refcount_block(BlockDriverState *bs, |
585f8587 FB |
2305 | int64_t refcount_block_offset) |
2306 | { | |
2307 | BDRVQcowState *s = bs->opaque; | |
2308 | int ret; | |
5fafdf24 | 2309 | ret = bdrv_pread(s->hd, refcount_block_offset, s->refcount_block_cache, |
585f8587 FB |
2310 | s->cluster_size); |
2311 | if (ret != s->cluster_size) | |
2312 | return -EIO; | |
2313 | s->refcount_block_cache_offset = refcount_block_offset; | |
2314 | return 0; | |
2315 | } | |
2316 | ||
2317 | static int get_refcount(BlockDriverState *bs, int64_t cluster_index) | |
2318 | { | |
2319 | BDRVQcowState *s = bs->opaque; | |
2320 | int refcount_table_index, block_index; | |
2321 | int64_t refcount_block_offset; | |
2322 | ||
2323 | refcount_table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT); | |
2324 | if (refcount_table_index >= s->refcount_table_size) | |
2325 | return 0; | |
2326 | refcount_block_offset = s->refcount_table[refcount_table_index]; | |
2327 | if (!refcount_block_offset) | |
2328 | return 0; | |
2329 | if (refcount_block_offset != s->refcount_block_cache_offset) { | |
2330 | /* better than nothing: return allocated if read error */ | |
2331 | if (load_refcount_block(bs, refcount_block_offset) < 0) | |
2332 | return 1; | |
2333 | } | |
5fafdf24 | 2334 | block_index = cluster_index & |
585f8587 FB |
2335 | ((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1); |
2336 | return be16_to_cpu(s->refcount_block_cache[block_index]); | |
2337 | } | |
2338 | ||
2339 | /* return < 0 if error */ | |
2340 | static int64_t alloc_clusters_noref(BlockDriverState *bs, int64_t size) | |
2341 | { | |
2342 | BDRVQcowState *s = bs->opaque; | |
2343 | int i, nb_clusters; | |
2344 | ||
6db6c638 AL |
2345 | nb_clusters = size_to_clusters(s, size); |
2346 | retry: | |
2347 | for(i = 0; i < nb_clusters; i++) { | |
2348 | int64_t i = s->free_cluster_index++; | |
2349 | if (get_refcount(bs, i) != 0) | |
2350 | goto retry; | |
2351 | } | |
585f8587 | 2352 | #ifdef DEBUG_ALLOC2 |
6db6c638 AL |
2353 | printf("alloc_clusters: size=%lld -> %lld\n", |
2354 | size, | |
2355 | (s->free_cluster_index - nb_clusters) << s->cluster_bits); | |
585f8587 | 2356 | #endif |
6db6c638 | 2357 | return (s->free_cluster_index - nb_clusters) << s->cluster_bits; |
585f8587 FB |
2358 | } |
2359 | ||
2360 | static int64_t alloc_clusters(BlockDriverState *bs, int64_t size) | |
2361 | { | |
2362 | int64_t offset; | |
2363 | ||
2364 | offset = alloc_clusters_noref(bs, size); | |
2365 | update_refcount(bs, offset, size, 1); | |
2366 | return offset; | |
2367 | } | |
2368 | ||
2369 | /* only used to allocate compressed sectors. We try to allocate | |
2370 | contiguous sectors. size must be <= cluster_size */ | |
2371 | static int64_t alloc_bytes(BlockDriverState *bs, int size) | |
2372 | { | |
2373 | BDRVQcowState *s = bs->opaque; | |
2374 | int64_t offset, cluster_offset; | |
2375 | int free_in_cluster; | |
3b46e624 | 2376 | |
585f8587 FB |
2377 | assert(size > 0 && size <= s->cluster_size); |
2378 | if (s->free_byte_offset == 0) { | |
2379 | s->free_byte_offset = alloc_clusters(bs, s->cluster_size); | |
2380 | } | |
2381 | redo: | |
5fafdf24 | 2382 | free_in_cluster = s->cluster_size - |
585f8587 FB |
2383 | (s->free_byte_offset & (s->cluster_size - 1)); |
2384 | if (size <= free_in_cluster) { | |
2385 | /* enough space in current cluster */ | |
2386 | offset = s->free_byte_offset; | |
2387 | s->free_byte_offset += size; | |
2388 | free_in_cluster -= size; | |
2389 | if (free_in_cluster == 0) | |
2390 | s->free_byte_offset = 0; | |
2391 | if ((offset & (s->cluster_size - 1)) != 0) | |
2392 | update_cluster_refcount(bs, offset >> s->cluster_bits, 1); | |
2393 | } else { | |
2394 | offset = alloc_clusters(bs, s->cluster_size); | |
2395 | cluster_offset = s->free_byte_offset & ~(s->cluster_size - 1); | |
2396 | if ((cluster_offset + s->cluster_size) == offset) { | |
2397 | /* we are lucky: contiguous data */ | |
2398 | offset = s->free_byte_offset; | |
2399 | update_cluster_refcount(bs, offset >> s->cluster_bits, 1); | |
2400 | s->free_byte_offset += size; | |
2401 | } else { | |
2402 | s->free_byte_offset = offset; | |
2403 | goto redo; | |
2404 | } | |
2405 | } | |
2406 | return offset; | |
2407 | } | |
2408 | ||
5fafdf24 | 2409 | static void free_clusters(BlockDriverState *bs, |
585f8587 FB |
2410 | int64_t offset, int64_t size) |
2411 | { | |
2412 | update_refcount(bs, offset, size, -1); | |
2413 | } | |
2414 | ||
2415 | static int grow_refcount_table(BlockDriverState *bs, int min_size) | |
2416 | { | |
2417 | BDRVQcowState *s = bs->opaque; | |
2418 | int new_table_size, new_table_size2, refcount_table_clusters, i, ret; | |
2419 | uint64_t *new_table; | |
2420 | int64_t table_offset; | |
643e5399 | 2421 | uint8_t data[12]; |
23be50f1 TS |
2422 | int old_table_size; |
2423 | int64_t old_table_offset; | |
585f8587 FB |
2424 | |
2425 | if (min_size <= s->refcount_table_size) | |
2426 | return 0; | |
2427 | /* compute new table size */ | |
2428 | refcount_table_clusters = s->refcount_table_size >> (s->cluster_bits - 3); | |
2429 | for(;;) { | |
2430 | if (refcount_table_clusters == 0) { | |
2431 | refcount_table_clusters = 1; | |
2432 | } else { | |
2433 | refcount_table_clusters = (refcount_table_clusters * 3 + 1) / 2; | |
2434 | } | |
2435 | new_table_size = refcount_table_clusters << (s->cluster_bits - 3); | |
2436 | if (min_size <= new_table_size) | |
2437 | break; | |
2438 | } | |
15e6690a FB |
2439 | #ifdef DEBUG_ALLOC2 |
2440 | printf("grow_refcount_table from %d to %d\n", | |
2441 | s->refcount_table_size, | |
2442 | new_table_size); | |
2443 | #endif | |
585f8587 FB |
2444 | new_table_size2 = new_table_size * sizeof(uint64_t); |
2445 | new_table = qemu_mallocz(new_table_size2); | |
5fafdf24 | 2446 | memcpy(new_table, s->refcount_table, |
585f8587 FB |
2447 | s->refcount_table_size * sizeof(uint64_t)); |
2448 | for(i = 0; i < s->refcount_table_size; i++) | |
2449 | cpu_to_be64s(&new_table[i]); | |
2450 | /* Note: we cannot update the refcount now to avoid recursion */ | |
2451 | table_offset = alloc_clusters_noref(bs, new_table_size2); | |
2452 | ret = bdrv_pwrite(s->hd, table_offset, new_table, new_table_size2); | |
5fafdf24 | 2453 | if (ret != new_table_size2) |
585f8587 FB |
2454 | goto fail; |
2455 | for(i = 0; i < s->refcount_table_size; i++) | |
2456 | be64_to_cpus(&new_table[i]); | |
2457 | ||
643e5399 AL |
2458 | cpu_to_be64w((uint64_t*)data, table_offset); |
2459 | cpu_to_be32w((uint32_t*)(data + 8), refcount_table_clusters); | |
585f8587 | 2460 | if (bdrv_pwrite(s->hd, offsetof(QCowHeader, refcount_table_offset), |
643e5399 | 2461 | data, sizeof(data)) != sizeof(data)) |
585f8587 FB |
2462 | goto fail; |
2463 | qemu_free(s->refcount_table); | |
23be50f1 TS |
2464 | old_table_offset = s->refcount_table_offset; |
2465 | old_table_size = s->refcount_table_size; | |
585f8587 FB |
2466 | s->refcount_table = new_table; |
2467 | s->refcount_table_size = new_table_size; | |
a4080ece | 2468 | s->refcount_table_offset = table_offset; |
585f8587 FB |
2469 | |
2470 | update_refcount(bs, table_offset, new_table_size2, 1); | |
23be50f1 | 2471 | free_clusters(bs, old_table_offset, old_table_size * sizeof(uint64_t)); |
585f8587 FB |
2472 | return 0; |
2473 | fail: | |
2474 | free_clusters(bs, table_offset, new_table_size2); | |
2475 | qemu_free(new_table); | |
2476 | return -EIO; | |
2477 | } | |
2478 | ||
2479 | /* addend must be 1 or -1 */ | |
2480 | /* XXX: cache several refcount block clusters ? */ | |
5fafdf24 | 2481 | static int update_cluster_refcount(BlockDriverState *bs, |
585f8587 FB |
2482 | int64_t cluster_index, |
2483 | int addend) | |
2484 | { | |
2485 | BDRVQcowState *s = bs->opaque; | |
2486 | int64_t offset, refcount_block_offset; | |
2487 | int ret, refcount_table_index, block_index, refcount; | |
2488 | uint64_t data64; | |
2489 | ||
2490 | refcount_table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT); | |
2491 | if (refcount_table_index >= s->refcount_table_size) { | |
2492 | if (addend < 0) | |
2493 | return -EINVAL; | |
2494 | ret = grow_refcount_table(bs, refcount_table_index + 1); | |
2495 | if (ret < 0) | |
2496 | return ret; | |
2497 | } | |
2498 | refcount_block_offset = s->refcount_table[refcount_table_index]; | |
2499 | if (!refcount_block_offset) { | |
2500 | if (addend < 0) | |
2501 | return -EINVAL; | |
2502 | /* create a new refcount block */ | |
2503 | /* Note: we cannot update the refcount now to avoid recursion */ | |
2504 | offset = alloc_clusters_noref(bs, s->cluster_size); | |
2505 | memset(s->refcount_block_cache, 0, s->cluster_size); | |
2506 | ret = bdrv_pwrite(s->hd, offset, s->refcount_block_cache, s->cluster_size); | |
2507 | if (ret != s->cluster_size) | |
2508 | return -EINVAL; | |
2509 | s->refcount_table[refcount_table_index] = offset; | |
2510 | data64 = cpu_to_be64(offset); | |
5fafdf24 TS |
2511 | ret = bdrv_pwrite(s->hd, s->refcount_table_offset + |
2512 | refcount_table_index * sizeof(uint64_t), | |
585f8587 FB |
2513 | &data64, sizeof(data64)); |
2514 | if (ret != sizeof(data64)) | |
2515 | return -EINVAL; | |
2516 | ||
2517 | refcount_block_offset = offset; | |
2518 | s->refcount_block_cache_offset = offset; | |
2519 | update_refcount(bs, offset, s->cluster_size, 1); | |
2520 | } else { | |
2521 | if (refcount_block_offset != s->refcount_block_cache_offset) { | |
2522 | if (load_refcount_block(bs, refcount_block_offset) < 0) | |
2523 | return -EIO; | |
2524 | } | |
2525 | } | |
2526 | /* we can update the count and save it */ | |
5fafdf24 | 2527 | block_index = cluster_index & |
585f8587 FB |
2528 | ((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1); |
2529 | refcount = be16_to_cpu(s->refcount_block_cache[block_index]); | |
2530 | refcount += addend; | |
2531 | if (refcount < 0 || refcount > 0xffff) | |
2532 | return -EINVAL; | |
2533 | if (refcount == 0 && cluster_index < s->free_cluster_index) { | |
2534 | s->free_cluster_index = cluster_index; | |
2535 | } | |
2536 | s->refcount_block_cache[block_index] = cpu_to_be16(refcount); | |
5fafdf24 TS |
2537 | if (bdrv_pwrite(s->hd, |
2538 | refcount_block_offset + (block_index << REFCOUNT_SHIFT), | |
585f8587 FB |
2539 | &s->refcount_block_cache[block_index], 2) != 2) |
2540 | return -EIO; | |
2541 | return refcount; | |
2542 | } | |
2543 | ||
5fafdf24 TS |
2544 | static void update_refcount(BlockDriverState *bs, |
2545 | int64_t offset, int64_t length, | |
585f8587 FB |
2546 | int addend) |
2547 | { | |
2548 | BDRVQcowState *s = bs->opaque; | |
2549 | int64_t start, last, cluster_offset; | |
2550 | ||
2551 | #ifdef DEBUG_ALLOC2 | |
5fafdf24 | 2552 | printf("update_refcount: offset=%lld size=%lld addend=%d\n", |
585f8587 FB |
2553 | offset, length, addend); |
2554 | #endif | |
2555 | if (length <= 0) | |
2556 | return; | |
2557 | start = offset & ~(s->cluster_size - 1); | |
2558 | last = (offset + length - 1) & ~(s->cluster_size - 1); | |
5fafdf24 | 2559 | for(cluster_offset = start; cluster_offset <= last; |
585f8587 FB |
2560 | cluster_offset += s->cluster_size) { |
2561 | update_cluster_refcount(bs, cluster_offset >> s->cluster_bits, addend); | |
2562 | } | |
2563 | } | |
2564 | ||
e97fc193 AL |
2565 | /* |
2566 | * Increases the refcount for a range of clusters in a given refcount table. | |
2567 | * This is used to construct a temporary refcount table out of L1 and L2 tables | |
2568 | * which can be compared the the refcount table saved in the image. | |
2569 | * | |
2570 | * Returns the number of errors in the image that were found | |
2571 | */ | |
2572 | static int inc_refcounts(BlockDriverState *bs, | |
5fafdf24 | 2573 | uint16_t *refcount_table, |
585f8587 FB |
2574 | int refcount_table_size, |
2575 | int64_t offset, int64_t size) | |
2576 | { | |
2577 | BDRVQcowState *s = bs->opaque; | |
2578 | int64_t start, last, cluster_offset; | |
2579 | int k; | |
e97fc193 | 2580 | int errors = 0; |
3b46e624 | 2581 | |
585f8587 | 2582 | if (size <= 0) |
e97fc193 | 2583 | return 0; |
585f8587 FB |
2584 | |
2585 | start = offset & ~(s->cluster_size - 1); | |
2586 | last = (offset + size - 1) & ~(s->cluster_size - 1); | |
5fafdf24 | 2587 | for(cluster_offset = start; cluster_offset <= last; |
585f8587 FB |
2588 | cluster_offset += s->cluster_size) { |
2589 | k = cluster_offset >> s->cluster_bits; | |
2590 | if (k < 0 || k >= refcount_table_size) { | |
8ddbc04f AL |
2591 | fprintf(stderr, "ERROR: invalid cluster offset=0x%" PRIx64 "\n", |
2592 | cluster_offset); | |
e97fc193 | 2593 | errors++; |
585f8587 FB |
2594 | } else { |
2595 | if (++refcount_table[k] == 0) { | |
8ddbc04f AL |
2596 | fprintf(stderr, "ERROR: overflow cluster offset=0x%" PRIx64 |
2597 | "\n", cluster_offset); | |
e97fc193 | 2598 | errors++; |
585f8587 FB |
2599 | } |
2600 | } | |
2601 | } | |
e97fc193 AL |
2602 | |
2603 | return errors; | |
585f8587 FB |
2604 | } |
2605 | ||
ae2f14af AL |
2606 | /* |
2607 | * Increases the refcount in the given refcount table for the all clusters | |
2608 | * referenced in the L2 table. While doing so, performs some checks on L2 | |
2609 | * entries. | |
2610 | * | |
2611 | * Returns the number of errors found by the checks or -errno if an internal | |
2612 | * error occurred. | |
2613 | */ | |
2614 | static int check_refcounts_l2(BlockDriverState *bs, | |
2615 | uint16_t *refcount_table, int refcount_table_size, int64_t l2_offset, | |
2616 | int check_copied) | |
2617 | { | |
2618 | BDRVQcowState *s = bs->opaque; | |
2619 | uint64_t *l2_table, offset; | |
2620 | int i, l2_size, nb_csectors, refcount; | |
2621 | int errors = 0; | |
2622 | ||
2623 | /* Read L2 table from disk */ | |
2624 | l2_size = s->l2_size * sizeof(uint64_t); | |
2625 | l2_table = qemu_malloc(l2_size); | |
2626 | ||
2627 | if (bdrv_pread(s->hd, l2_offset, l2_table, l2_size) != l2_size) | |
2628 | goto fail; | |
2629 | ||
2630 | /* Do the actual checks */ | |
2631 | for(i = 0; i < s->l2_size; i++) { | |
2632 | offset = be64_to_cpu(l2_table[i]); | |
2633 | if (offset != 0) { | |
2634 | if (offset & QCOW_OFLAG_COMPRESSED) { | |
2635 | /* Compressed clusters don't have QCOW_OFLAG_COPIED */ | |
2636 | if (offset & QCOW_OFLAG_COPIED) { | |
2637 | fprintf(stderr, "ERROR: cluster %" PRId64 ": " | |
2638 | "copied flag must never be set for compressed " | |
2639 | "clusters\n", offset >> s->cluster_bits); | |
2640 | offset &= ~QCOW_OFLAG_COPIED; | |
2641 | errors++; | |
2642 | } | |
2643 | ||
2644 | /* Mark cluster as used */ | |
2645 | nb_csectors = ((offset >> s->csize_shift) & | |
2646 | s->csize_mask) + 1; | |
2647 | offset &= s->cluster_offset_mask; | |
2648 | errors += inc_refcounts(bs, refcount_table, | |
2649 | refcount_table_size, | |
2650 | offset & ~511, nb_csectors * 512); | |
2651 | } else { | |
2652 | /* QCOW_OFLAG_COPIED must be set iff refcount == 1 */ | |
2653 | if (check_copied) { | |
2654 | uint64_t entry = offset; | |
2655 | offset &= ~QCOW_OFLAG_COPIED; | |
2656 | refcount = get_refcount(bs, offset >> s->cluster_bits); | |
2657 | if ((refcount == 1) != ((entry & QCOW_OFLAG_COPIED) != 0)) { | |
2658 | fprintf(stderr, "ERROR OFLAG_COPIED: offset=%" | |
2659 | PRIx64 " refcount=%d\n", entry, refcount); | |
2660 | errors++; | |
2661 | } | |
2662 | } | |
2663 | ||
2664 | /* Mark cluster as used */ | |
2665 | offset &= ~QCOW_OFLAG_COPIED; | |
2666 | errors += inc_refcounts(bs, refcount_table, | |
2667 | refcount_table_size, | |
2668 | offset, s->cluster_size); | |
54c42368 AL |
2669 | |
2670 | /* Correct offsets are cluster aligned */ | |
2671 | if (offset & (s->cluster_size - 1)) { | |
2672 | fprintf(stderr, "ERROR offset=%" PRIx64 ": Cluster is not " | |
2673 | "properly aligned; L2 entry corrupted.\n", offset); | |
2674 | errors++; | |
2675 | } | |
ae2f14af AL |
2676 | } |
2677 | } | |
2678 | } | |
2679 | ||
2680 | qemu_free(l2_table); | |
2681 | return errors; | |
2682 | ||
2683 | fail: | |
2684 | fprintf(stderr, "ERROR: I/O error in check_refcounts_l1\n"); | |
2685 | qemu_free(l2_table); | |
2686 | return -EIO; | |
2687 | } | |
2688 | ||
2689 | /* | |
2690 | * Increases the refcount for the L1 table, its L2 tables and all referenced | |
2691 | * clusters in the given refcount table. While doing so, performs some checks | |
2692 | * on L1 and L2 entries. | |
2693 | * | |
2694 | * Returns the number of errors found by the checks or -errno if an internal | |
2695 | * error occurred. | |
2696 | */ | |
5fafdf24 TS |
2697 | static int check_refcounts_l1(BlockDriverState *bs, |
2698 | uint16_t *refcount_table, | |
585f8587 FB |
2699 | int refcount_table_size, |
2700 | int64_t l1_table_offset, int l1_size, | |
2701 | int check_copied) | |
2702 | { | |
2703 | BDRVQcowState *s = bs->opaque; | |
ae2f14af AL |
2704 | uint64_t *l1_table, l2_offset, l1_size2; |
2705 | int i, refcount, ret; | |
e97fc193 | 2706 | int errors = 0; |
585f8587 | 2707 | |
585f8587 FB |
2708 | l1_size2 = l1_size * sizeof(uint64_t); |
2709 | ||
ae2f14af | 2710 | /* Mark L1 table as used */ |
e97fc193 | 2711 | errors += inc_refcounts(bs, refcount_table, refcount_table_size, |
585f8587 FB |
2712 | l1_table_offset, l1_size2); |
2713 | ||
ae2f14af | 2714 | /* Read L1 table entries from disk */ |
585f8587 | 2715 | l1_table = qemu_malloc(l1_size2); |
5fafdf24 | 2716 | if (bdrv_pread(s->hd, l1_table_offset, |
585f8587 FB |
2717 | l1_table, l1_size2) != l1_size2) |
2718 | goto fail; | |
2719 | for(i = 0;i < l1_size; i++) | |
2720 | be64_to_cpus(&l1_table[i]); | |
3b46e624 | 2721 | |
ae2f14af | 2722 | /* Do the actual checks */ |
585f8587 FB |
2723 | for(i = 0; i < l1_size; i++) { |
2724 | l2_offset = l1_table[i]; | |
2725 | if (l2_offset) { | |
ae2f14af | 2726 | /* QCOW_OFLAG_COPIED must be set iff refcount == 1 */ |
585f8587 | 2727 | if (check_copied) { |
ae2f14af AL |
2728 | refcount = get_refcount(bs, (l2_offset & ~QCOW_OFLAG_COPIED) |
2729 | >> s->cluster_bits); | |
585f8587 | 2730 | if ((refcount == 1) != ((l2_offset & QCOW_OFLAG_COPIED) != 0)) { |
8ddbc04f AL |
2731 | fprintf(stderr, "ERROR OFLAG_COPIED: l2_offset=%" PRIx64 |
2732 | " refcount=%d\n", l2_offset, refcount); | |
e97fc193 | 2733 | errors++; |
585f8587 FB |
2734 | } |
2735 | } | |
ae2f14af AL |
2736 | |
2737 | /* Mark L2 table as used */ | |
585f8587 | 2738 | l2_offset &= ~QCOW_OFLAG_COPIED; |
e97fc193 | 2739 | errors += inc_refcounts(bs, refcount_table, |
585f8587 FB |
2740 | refcount_table_size, |
2741 | l2_offset, | |
2742 | s->cluster_size); | |
ae2f14af | 2743 | |
54c42368 AL |
2744 | /* L2 tables are cluster aligned */ |
2745 | if (l2_offset & (s->cluster_size - 1)) { | |
2746 | fprintf(stderr, "ERROR l2_offset=%" PRIx64 ": Table is not " | |
2747 | "cluster aligned; L1 entry corrupted\n", l2_offset); | |
2748 | errors++; | |
2749 | } | |
2750 | ||
ae2f14af AL |
2751 | /* Process and check L2 entries */ |
2752 | ret = check_refcounts_l2(bs, refcount_table, refcount_table_size, | |
2753 | l2_offset, check_copied); | |
2754 | if (ret < 0) { | |
2755 | goto fail; | |
2756 | } | |
2757 | errors += ret; | |
585f8587 FB |
2758 | } |
2759 | } | |
2760 | qemu_free(l1_table); | |
e97fc193 | 2761 | return errors; |
ae2f14af AL |
2762 | |
2763 | fail: | |
8ddbc04f | 2764 | fprintf(stderr, "ERROR: I/O error in check_refcounts_l1\n"); |
585f8587 | 2765 | qemu_free(l1_table); |
585f8587 FB |
2766 | return -EIO; |
2767 | } | |
2768 | ||
e97fc193 AL |
2769 | /* |
2770 | * Checks an image for refcount consistency. | |
2771 | * | |
2772 | * Returns 0 if no errors are found, the number of errors in case the image is | |
2773 | * detected as corrupted, and -errno when an internal error occured. | |
2774 | */ | |
2775 | static int check_refcounts(BlockDriverState *bs) | |
585f8587 FB |
2776 | { |
2777 | BDRVQcowState *s = bs->opaque; | |
2778 | int64_t size; | |
2779 | int nb_clusters, refcount1, refcount2, i; | |
2780 | QCowSnapshot *sn; | |
2781 | uint16_t *refcount_table; | |
e97fc193 | 2782 | int ret, errors = 0; |
585f8587 FB |
2783 | |
2784 | size = bdrv_getlength(s->hd); | |
6db6c638 | 2785 | nb_clusters = size_to_clusters(s, size); |
585f8587 | 2786 | refcount_table = qemu_mallocz(nb_clusters * sizeof(uint16_t)); |
15e6690a | 2787 | |
585f8587 | 2788 | /* header */ |
e97fc193 | 2789 | errors += inc_refcounts(bs, refcount_table, nb_clusters, |
585f8587 | 2790 | 0, s->cluster_size); |
3b46e624 | 2791 | |
ae2f14af | 2792 | /* current L1 table */ |
e97fc193 | 2793 | ret = check_refcounts_l1(bs, refcount_table, nb_clusters, |
585f8587 | 2794 | s->l1_table_offset, s->l1_size, 1); |
e97fc193 AL |
2795 | if (ret < 0) { |
2796 | return ret; | |
2797 | } | |
2798 | errors += ret; | |
585f8587 FB |
2799 | |
2800 | /* snapshots */ | |
2801 | for(i = 0; i < s->nb_snapshots; i++) { | |
2802 | sn = s->snapshots + i; | |
2803 | check_refcounts_l1(bs, refcount_table, nb_clusters, | |
2804 | sn->l1_table_offset, sn->l1_size, 0); | |
2805 | } | |
e97fc193 | 2806 | errors += inc_refcounts(bs, refcount_table, nb_clusters, |
585f8587 FB |
2807 | s->snapshots_offset, s->snapshots_size); |
2808 | ||
2809 | /* refcount data */ | |
e97fc193 | 2810 | errors += inc_refcounts(bs, refcount_table, nb_clusters, |
5fafdf24 | 2811 | s->refcount_table_offset, |
585f8587 FB |
2812 | s->refcount_table_size * sizeof(uint64_t)); |
2813 | for(i = 0; i < s->refcount_table_size; i++) { | |
2814 | int64_t offset; | |
2815 | offset = s->refcount_table[i]; | |
2816 | if (offset != 0) { | |
e97fc193 | 2817 | errors += inc_refcounts(bs, refcount_table, nb_clusters, |
585f8587 FB |
2818 | offset, s->cluster_size); |
2819 | } | |
2820 | } | |
2821 | ||
2822 | /* compare ref counts */ | |
2823 | for(i = 0; i < nb_clusters; i++) { | |
2824 | refcount1 = get_refcount(bs, i); | |
2825 | refcount2 = refcount_table[i]; | |
e97fc193 | 2826 | if (refcount1 != refcount2) { |
8ddbc04f | 2827 | fprintf(stderr, "ERROR cluster %d refcount=%d reference=%d\n", |
585f8587 | 2828 | i, refcount1, refcount2); |
e97fc193 AL |
2829 | errors++; |
2830 | } | |
585f8587 FB |
2831 | } |
2832 | ||
2833 | qemu_free(refcount_table); | |
e97fc193 AL |
2834 | |
2835 | return errors; | |
2836 | } | |
2837 | ||
2838 | static int qcow_check(BlockDriverState *bs) | |
2839 | { | |
2840 | return check_refcounts(bs); | |
585f8587 FB |
2841 | } |
2842 | ||
2843 | #if 0 | |
2844 | static void dump_refcounts(BlockDriverState *bs) | |
2845 | { | |
2846 | BDRVQcowState *s = bs->opaque; | |
2847 | int64_t nb_clusters, k, k1, size; | |
2848 | int refcount; | |
2849 | ||
2850 | size = bdrv_getlength(s->hd); | |
6db6c638 | 2851 | nb_clusters = size_to_clusters(s, size); |
585f8587 FB |
2852 | for(k = 0; k < nb_clusters;) { |
2853 | k1 = k; | |
2854 | refcount = get_refcount(bs, k); | |
2855 | k++; | |
2856 | while (k < nb_clusters && get_refcount(bs, k) == refcount) | |
2857 | k++; | |
2858 | printf("%lld: refcount=%d nb=%lld\n", k, refcount, k - k1); | |
2859 | } | |
2860 | } | |
2861 | #endif | |
585f8587 | 2862 | |
178e08a5 AL |
2863 | static int qcow_put_buffer(BlockDriverState *bs, const uint8_t *buf, |
2864 | int64_t pos, int size) | |
2865 | { | |
2866 | int growable = bs->growable; | |
2867 | ||
2868 | bs->growable = 1; | |
2869 | bdrv_pwrite(bs, pos, buf, size); | |
2870 | bs->growable = growable; | |
2871 | ||
2872 | return size; | |
2873 | } | |
2874 | ||
2875 | static int qcow_get_buffer(BlockDriverState *bs, uint8_t *buf, | |
2876 | int64_t pos, int size) | |
2877 | { | |
2878 | int growable = bs->growable; | |
2879 | int ret; | |
2880 | ||
2881 | bs->growable = 1; | |
2882 | ret = bdrv_pread(bs, pos, buf, size); | |
2883 | bs->growable = growable; | |
2884 | ||
2885 | return ret; | |
2886 | } | |
2887 | ||
585f8587 | 2888 | BlockDriver bdrv_qcow2 = { |
e60f469c AJ |
2889 | .format_name = "qcow2", |
2890 | .instance_size = sizeof(BDRVQcowState), | |
2891 | .bdrv_probe = qcow_probe, | |
2892 | .bdrv_open = qcow_open, | |
2893 | .bdrv_close = qcow_close, | |
2894 | .bdrv_create = qcow_create, | |
2895 | .bdrv_flush = qcow_flush, | |
2896 | .bdrv_is_allocated = qcow_is_allocated, | |
2897 | .bdrv_set_key = qcow_set_key, | |
2898 | .bdrv_make_empty = qcow_make_empty, | |
2899 | ||
f141eafe AL |
2900 | .bdrv_aio_readv = qcow_aio_readv, |
2901 | .bdrv_aio_writev = qcow_aio_writev, | |
e60f469c AJ |
2902 | .bdrv_aio_cancel = qcow_aio_cancel, |
2903 | .aiocb_size = sizeof(QCowAIOCB), | |
585f8587 FB |
2904 | .bdrv_write_compressed = qcow_write_compressed, |
2905 | ||
2906 | .bdrv_snapshot_create = qcow_snapshot_create, | |
e60f469c | 2907 | .bdrv_snapshot_goto = qcow_snapshot_goto, |
585f8587 | 2908 | .bdrv_snapshot_delete = qcow_snapshot_delete, |
e60f469c AJ |
2909 | .bdrv_snapshot_list = qcow_snapshot_list, |
2910 | .bdrv_get_info = qcow_get_info, | |
f965509c | 2911 | |
178e08a5 AL |
2912 | .bdrv_put_buffer = qcow_put_buffer, |
2913 | .bdrv_get_buffer = qcow_get_buffer, | |
2914 | ||
f965509c | 2915 | .bdrv_create2 = qcow_create2, |
e97fc193 | 2916 | .bdrv_check = qcow_check, |
585f8587 | 2917 | }; |