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Commit | Line | Data |
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585f8587 FB |
1 | /* |
2 | * Block driver for the QCOW version 2 format | |
5fafdf24 | 3 | * |
585f8587 | 4 | * Copyright (c) 2004-2006 Fabrice Bellard |
5fafdf24 | 5 | * |
585f8587 FB |
6 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
7 | * of this software and associated documentation files (the "Software"), to deal | |
8 | * in the Software without restriction, including without limitation the rights | |
9 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell | |
10 | * copies of the Software, and to permit persons to whom the Software is | |
11 | * furnished to do so, subject to the following conditions: | |
12 | * | |
13 | * The above copyright notice and this permission notice shall be included in | |
14 | * all copies or substantial portions of the Software. | |
15 | * | |
16 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
17 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
18 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL | |
19 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
20 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, | |
21 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN | |
22 | * THE SOFTWARE. | |
23 | */ | |
faf07963 | 24 | #include "qemu-common.h" |
585f8587 | 25 | #include "block_int.h" |
5efa9d5a | 26 | #include "module.h" |
585f8587 FB |
27 | #include <zlib.h> |
28 | #include "aes.h" | |
f7d0fe02 | 29 | #include "block/qcow2.h" |
585f8587 FB |
30 | |
31 | /* | |
32 | Differences with QCOW: | |
33 | ||
34 | - Support for multiple incremental snapshots. | |
35 | - Memory management by reference counts. | |
36 | - Clusters which have a reference count of one have the bit | |
37 | QCOW_OFLAG_COPIED to optimize write performance. | |
5fafdf24 | 38 | - Size of compressed clusters is stored in sectors to reduce bit usage |
585f8587 FB |
39 | in the cluster offsets. |
40 | - Support for storing additional data (such as the VM state) in the | |
3b46e624 | 41 | snapshots. |
585f8587 FB |
42 | - If a backing store is used, the cluster size is not constrained |
43 | (could be backported to QCOW). | |
44 | - L2 tables have always a size of one cluster. | |
45 | */ | |
46 | ||
9b80ddf3 AL |
47 | |
48 | typedef struct { | |
49 | uint32_t magic; | |
50 | uint32_t len; | |
51 | } QCowExtension; | |
52 | #define QCOW_EXT_MAGIC_END 0 | |
f965509c | 53 | #define QCOW_EXT_MAGIC_BACKING_FORMAT 0xE2792ACA |
9b80ddf3 | 54 | |
585f8587 FB |
55 | static int qcow_probe(const uint8_t *buf, int buf_size, const char *filename) |
56 | { | |
57 | const QCowHeader *cow_header = (const void *)buf; | |
3b46e624 | 58 | |
585f8587 FB |
59 | if (buf_size >= sizeof(QCowHeader) && |
60 | be32_to_cpu(cow_header->magic) == QCOW_MAGIC && | |
5fafdf24 | 61 | be32_to_cpu(cow_header->version) == QCOW_VERSION) |
585f8587 FB |
62 | return 100; |
63 | else | |
64 | return 0; | |
65 | } | |
66 | ||
9b80ddf3 AL |
67 | |
68 | /* | |
69 | * read qcow2 extension and fill bs | |
70 | * start reading from start_offset | |
71 | * finish reading upon magic of value 0 or when end_offset reached | |
72 | * unknown magic is skipped (future extension this version knows nothing about) | |
73 | * return 0 upon success, non-0 otherwise | |
74 | */ | |
75 | static int qcow_read_extensions(BlockDriverState *bs, uint64_t start_offset, | |
76 | uint64_t end_offset) | |
77 | { | |
9b80ddf3 AL |
78 | QCowExtension ext; |
79 | uint64_t offset; | |
80 | ||
81 | #ifdef DEBUG_EXT | |
82 | printf("qcow_read_extensions: start=%ld end=%ld\n", start_offset, end_offset); | |
83 | #endif | |
84 | offset = start_offset; | |
85 | while (offset < end_offset) { | |
86 | ||
87 | #ifdef DEBUG_EXT | |
88 | /* Sanity check */ | |
89 | if (offset > s->cluster_size) | |
90 | printf("qcow_handle_extension: suspicious offset %lu\n", offset); | |
91 | ||
92 | printf("attemting to read extended header in offset %lu\n", offset); | |
93 | #endif | |
94 | ||
66f82cee | 95 | if (bdrv_pread(bs->file, offset, &ext, sizeof(ext)) != sizeof(ext)) { |
0bfcd599 BS |
96 | fprintf(stderr, "qcow_handle_extension: ERROR: " |
97 | "pread fail from offset %" PRIu64 "\n", | |
98 | offset); | |
9b80ddf3 AL |
99 | return 1; |
100 | } | |
101 | be32_to_cpus(&ext.magic); | |
102 | be32_to_cpus(&ext.len); | |
103 | offset += sizeof(ext); | |
104 | #ifdef DEBUG_EXT | |
105 | printf("ext.magic = 0x%x\n", ext.magic); | |
106 | #endif | |
107 | switch (ext.magic) { | |
108 | case QCOW_EXT_MAGIC_END: | |
109 | return 0; | |
f965509c AL |
110 | |
111 | case QCOW_EXT_MAGIC_BACKING_FORMAT: | |
112 | if (ext.len >= sizeof(bs->backing_format)) { | |
113 | fprintf(stderr, "ERROR: ext_backing_format: len=%u too large" | |
4c978075 | 114 | " (>=%zu)\n", |
f965509c AL |
115 | ext.len, sizeof(bs->backing_format)); |
116 | return 2; | |
117 | } | |
66f82cee | 118 | if (bdrv_pread(bs->file, offset , bs->backing_format, |
f965509c AL |
119 | ext.len) != ext.len) |
120 | return 3; | |
121 | bs->backing_format[ext.len] = '\0'; | |
122 | #ifdef DEBUG_EXT | |
123 | printf("Qcow2: Got format extension %s\n", bs->backing_format); | |
124 | #endif | |
e1c7f0e3 | 125 | offset = ((offset + ext.len + 7) & ~7); |
f965509c AL |
126 | break; |
127 | ||
9b80ddf3 AL |
128 | default: |
129 | /* unknown magic -- just skip it */ | |
e1c7f0e3 | 130 | offset = ((offset + ext.len + 7) & ~7); |
9b80ddf3 AL |
131 | break; |
132 | } | |
133 | } | |
134 | ||
135 | return 0; | |
136 | } | |
137 | ||
138 | ||
66f82cee | 139 | static int qcow_open(BlockDriverState *bs, int flags) |
585f8587 FB |
140 | { |
141 | BDRVQcowState *s = bs->opaque; | |
419b19d9 | 142 | int len, i; |
585f8587 | 143 | QCowHeader header; |
9b80ddf3 | 144 | uint64_t ext_end; |
585f8587 | 145 | |
66f82cee | 146 | if (bdrv_pread(bs->file, 0, &header, sizeof(header)) != sizeof(header)) |
585f8587 FB |
147 | goto fail; |
148 | be32_to_cpus(&header.magic); | |
149 | be32_to_cpus(&header.version); | |
150 | be64_to_cpus(&header.backing_file_offset); | |
151 | be32_to_cpus(&header.backing_file_size); | |
152 | be64_to_cpus(&header.size); | |
153 | be32_to_cpus(&header.cluster_bits); | |
154 | be32_to_cpus(&header.crypt_method); | |
155 | be64_to_cpus(&header.l1_table_offset); | |
156 | be32_to_cpus(&header.l1_size); | |
157 | be64_to_cpus(&header.refcount_table_offset); | |
158 | be32_to_cpus(&header.refcount_table_clusters); | |
159 | be64_to_cpus(&header.snapshots_offset); | |
160 | be32_to_cpus(&header.nb_snapshots); | |
3b46e624 | 161 | |
585f8587 FB |
162 | if (header.magic != QCOW_MAGIC || header.version != QCOW_VERSION) |
163 | goto fail; | |
d191d12d | 164 | if (header.cluster_bits < MIN_CLUSTER_BITS || |
73c632ed | 165 | header.cluster_bits > MAX_CLUSTER_BITS) |
585f8587 FB |
166 | goto fail; |
167 | if (header.crypt_method > QCOW_CRYPT_AES) | |
168 | goto fail; | |
169 | s->crypt_method_header = header.crypt_method; | |
170 | if (s->crypt_method_header) | |
171 | bs->encrypted = 1; | |
172 | s->cluster_bits = header.cluster_bits; | |
173 | s->cluster_size = 1 << s->cluster_bits; | |
174 | s->cluster_sectors = 1 << (s->cluster_bits - 9); | |
175 | s->l2_bits = s->cluster_bits - 3; /* L2 is always one cluster */ | |
176 | s->l2_size = 1 << s->l2_bits; | |
177 | bs->total_sectors = header.size / 512; | |
178 | s->csize_shift = (62 - (s->cluster_bits - 8)); | |
179 | s->csize_mask = (1 << (s->cluster_bits - 8)) - 1; | |
180 | s->cluster_offset_mask = (1LL << s->csize_shift) - 1; | |
181 | s->refcount_table_offset = header.refcount_table_offset; | |
5fafdf24 | 182 | s->refcount_table_size = |
585f8587 FB |
183 | header.refcount_table_clusters << (s->cluster_bits - 3); |
184 | ||
185 | s->snapshots_offset = header.snapshots_offset; | |
186 | s->nb_snapshots = header.nb_snapshots; | |
187 | ||
188 | /* read the level 1 table */ | |
189 | s->l1_size = header.l1_size; | |
419b19d9 | 190 | s->l1_vm_state_index = size_to_l1(s, header.size); |
585f8587 FB |
191 | /* the L1 table must contain at least enough entries to put |
192 | header.size bytes */ | |
193 | if (s->l1_size < s->l1_vm_state_index) | |
194 | goto fail; | |
195 | s->l1_table_offset = header.l1_table_offset; | |
d191d12d SW |
196 | if (s->l1_size > 0) { |
197 | s->l1_table = qemu_mallocz( | |
198 | align_offset(s->l1_size * sizeof(uint64_t), 512)); | |
66f82cee | 199 | if (bdrv_pread(bs->file, s->l1_table_offset, s->l1_table, s->l1_size * sizeof(uint64_t)) != |
d191d12d SW |
200 | s->l1_size * sizeof(uint64_t)) |
201 | goto fail; | |
202 | for(i = 0;i < s->l1_size; i++) { | |
203 | be64_to_cpus(&s->l1_table[i]); | |
204 | } | |
585f8587 FB |
205 | } |
206 | /* alloc L2 cache */ | |
207 | s->l2_cache = qemu_malloc(s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t)); | |
585f8587 | 208 | s->cluster_cache = qemu_malloc(s->cluster_size); |
585f8587 | 209 | /* one more sector for decompressed data alignment */ |
095a9c58 AL |
210 | s->cluster_data = qemu_malloc(QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size |
211 | + 512); | |
585f8587 | 212 | s->cluster_cache_offset = -1; |
3b46e624 | 213 | |
ed6ccf0f | 214 | if (qcow2_refcount_init(bs) < 0) |
585f8587 FB |
215 | goto fail; |
216 | ||
72cf2d4f | 217 | QLIST_INIT(&s->cluster_allocs); |
f214978a | 218 | |
9b80ddf3 AL |
219 | /* read qcow2 extensions */ |
220 | if (header.backing_file_offset) | |
221 | ext_end = header.backing_file_offset; | |
222 | else | |
223 | ext_end = s->cluster_size; | |
224 | if (qcow_read_extensions(bs, sizeof(header), ext_end)) | |
225 | goto fail; | |
226 | ||
585f8587 FB |
227 | /* read the backing file name */ |
228 | if (header.backing_file_offset != 0) { | |
229 | len = header.backing_file_size; | |
230 | if (len > 1023) | |
231 | len = 1023; | |
66f82cee | 232 | if (bdrv_pread(bs->file, header.backing_file_offset, bs->backing_file, len) != len) |
585f8587 FB |
233 | goto fail; |
234 | bs->backing_file[len] = '\0'; | |
235 | } | |
ed6ccf0f | 236 | if (qcow2_read_snapshots(bs) < 0) |
585f8587 FB |
237 | goto fail; |
238 | ||
239 | #ifdef DEBUG_ALLOC | |
14899cdf | 240 | qcow2_check_refcounts(bs); |
585f8587 FB |
241 | #endif |
242 | return 0; | |
243 | ||
244 | fail: | |
ed6ccf0f KW |
245 | qcow2_free_snapshots(bs); |
246 | qcow2_refcount_close(bs); | |
585f8587 FB |
247 | qemu_free(s->l1_table); |
248 | qemu_free(s->l2_cache); | |
249 | qemu_free(s->cluster_cache); | |
250 | qemu_free(s->cluster_data); | |
585f8587 FB |
251 | return -1; |
252 | } | |
253 | ||
254 | static int qcow_set_key(BlockDriverState *bs, const char *key) | |
255 | { | |
256 | BDRVQcowState *s = bs->opaque; | |
257 | uint8_t keybuf[16]; | |
258 | int len, i; | |
3b46e624 | 259 | |
585f8587 FB |
260 | memset(keybuf, 0, 16); |
261 | len = strlen(key); | |
262 | if (len > 16) | |
263 | len = 16; | |
264 | /* XXX: we could compress the chars to 7 bits to increase | |
265 | entropy */ | |
266 | for(i = 0;i < len;i++) { | |
267 | keybuf[i] = key[i]; | |
268 | } | |
269 | s->crypt_method = s->crypt_method_header; | |
270 | ||
271 | if (AES_set_encrypt_key(keybuf, 128, &s->aes_encrypt_key) != 0) | |
272 | return -1; | |
273 | if (AES_set_decrypt_key(keybuf, 128, &s->aes_decrypt_key) != 0) | |
274 | return -1; | |
275 | #if 0 | |
276 | /* test */ | |
277 | { | |
278 | uint8_t in[16]; | |
279 | uint8_t out[16]; | |
280 | uint8_t tmp[16]; | |
281 | for(i=0;i<16;i++) | |
282 | in[i] = i; | |
283 | AES_encrypt(in, tmp, &s->aes_encrypt_key); | |
284 | AES_decrypt(tmp, out, &s->aes_decrypt_key); | |
285 | for(i = 0; i < 16; i++) | |
286 | printf(" %02x", tmp[i]); | |
287 | printf("\n"); | |
288 | for(i = 0; i < 16; i++) | |
289 | printf(" %02x", out[i]); | |
290 | printf("\n"); | |
291 | } | |
292 | #endif | |
293 | return 0; | |
294 | } | |
295 | ||
5fafdf24 | 296 | static int qcow_is_allocated(BlockDriverState *bs, int64_t sector_num, |
585f8587 FB |
297 | int nb_sectors, int *pnum) |
298 | { | |
585f8587 | 299 | uint64_t cluster_offset; |
1c46efaa | 300 | int ret; |
585f8587 | 301 | |
095a9c58 | 302 | *pnum = nb_sectors; |
1c46efaa KW |
303 | /* FIXME We can get errors here, but the bdrv_is_allocated interface can't |
304 | * pass them on today */ | |
305 | ret = qcow2_get_cluster_offset(bs, sector_num << 9, pnum, &cluster_offset); | |
306 | if (ret < 0) { | |
307 | *pnum = 0; | |
308 | } | |
095a9c58 | 309 | |
585f8587 FB |
310 | return (cluster_offset != 0); |
311 | } | |
312 | ||
a9465922 | 313 | /* handle reading after the end of the backing file */ |
bd28f835 KW |
314 | int qcow2_backing_read1(BlockDriverState *bs, QEMUIOVector *qiov, |
315 | int64_t sector_num, int nb_sectors) | |
a9465922 FB |
316 | { |
317 | int n1; | |
318 | if ((sector_num + nb_sectors) <= bs->total_sectors) | |
319 | return nb_sectors; | |
320 | if (sector_num >= bs->total_sectors) | |
321 | n1 = 0; | |
322 | else | |
323 | n1 = bs->total_sectors - sector_num; | |
bd28f835 KW |
324 | |
325 | qemu_iovec_memset(qiov, 0, 512 * (nb_sectors - n1)); | |
326 | ||
a9465922 FB |
327 | return n1; |
328 | } | |
329 | ||
ce1a14dc PB |
330 | typedef struct QCowAIOCB { |
331 | BlockDriverAIOCB common; | |
585f8587 | 332 | int64_t sector_num; |
f141eafe | 333 | QEMUIOVector *qiov; |
7b88e48b CH |
334 | int remaining_sectors; |
335 | int cur_nr_sectors; /* number of sectors in current iteration */ | |
bd28f835 | 336 | uint64_t bytes_done; |
585f8587 | 337 | uint64_t cluster_offset; |
5fafdf24 | 338 | uint8_t *cluster_data; |
585f8587 | 339 | BlockDriverAIOCB *hd_aiocb; |
c87c0672 | 340 | QEMUIOVector hd_qiov; |
1490791f | 341 | QEMUBH *bh; |
e976c6a1 | 342 | QCowL2Meta l2meta; |
72cf2d4f | 343 | QLIST_ENTRY(QCowAIOCB) next_depend; |
585f8587 FB |
344 | } QCowAIOCB; |
345 | ||
c16b5a2c CH |
346 | static void qcow_aio_cancel(BlockDriverAIOCB *blockacb) |
347 | { | |
b666d239 | 348 | QCowAIOCB *acb = container_of(blockacb, QCowAIOCB, common); |
c16b5a2c CH |
349 | if (acb->hd_aiocb) |
350 | bdrv_aio_cancel(acb->hd_aiocb); | |
351 | qemu_aio_release(acb); | |
352 | } | |
353 | ||
354 | static AIOPool qcow_aio_pool = { | |
355 | .aiocb_size = sizeof(QCowAIOCB), | |
356 | .cancel = qcow_aio_cancel, | |
357 | }; | |
358 | ||
1490791f AL |
359 | static void qcow_aio_read_cb(void *opaque, int ret); |
360 | static void qcow_aio_read_bh(void *opaque) | |
361 | { | |
362 | QCowAIOCB *acb = opaque; | |
363 | qemu_bh_delete(acb->bh); | |
364 | acb->bh = NULL; | |
365 | qcow_aio_read_cb(opaque, 0); | |
366 | } | |
367 | ||
a32ef786 AL |
368 | static int qcow_schedule_bh(QEMUBHFunc *cb, QCowAIOCB *acb) |
369 | { | |
370 | if (acb->bh) | |
371 | return -EIO; | |
372 | ||
373 | acb->bh = qemu_bh_new(cb, acb); | |
374 | if (!acb->bh) | |
375 | return -EIO; | |
376 | ||
377 | qemu_bh_schedule(acb->bh); | |
378 | ||
379 | return 0; | |
380 | } | |
381 | ||
585f8587 FB |
382 | static void qcow_aio_read_cb(void *opaque, int ret) |
383 | { | |
ce1a14dc PB |
384 | QCowAIOCB *acb = opaque; |
385 | BlockDriverState *bs = acb->common.bs; | |
585f8587 | 386 | BDRVQcowState *s = bs->opaque; |
a9465922 | 387 | int index_in_cluster, n1; |
585f8587 | 388 | |
ce1a14dc | 389 | acb->hd_aiocb = NULL; |
f141eafe AL |
390 | if (ret < 0) |
391 | goto done; | |
585f8587 | 392 | |
585f8587 | 393 | /* post process the read buffer */ |
ce1a14dc | 394 | if (!acb->cluster_offset) { |
585f8587 | 395 | /* nothing to do */ |
ce1a14dc | 396 | } else if (acb->cluster_offset & QCOW_OFLAG_COMPRESSED) { |
585f8587 FB |
397 | /* nothing to do */ |
398 | } else { | |
399 | if (s->crypt_method) { | |
bd28f835 KW |
400 | qcow2_encrypt_sectors(s, acb->sector_num, acb->cluster_data, |
401 | acb->cluster_data, acb->cur_nr_sectors, 0, &s->aes_decrypt_key); | |
402 | qemu_iovec_reset(&acb->hd_qiov); | |
403 | qemu_iovec_copy(&acb->hd_qiov, acb->qiov, acb->bytes_done, | |
404 | acb->cur_nr_sectors * 512); | |
405 | qemu_iovec_from_buffer(&acb->hd_qiov, acb->cluster_data, | |
406 | 512 * acb->cur_nr_sectors); | |
585f8587 FB |
407 | } |
408 | } | |
409 | ||
7b88e48b CH |
410 | acb->remaining_sectors -= acb->cur_nr_sectors; |
411 | acb->sector_num += acb->cur_nr_sectors; | |
bd28f835 | 412 | acb->bytes_done += acb->cur_nr_sectors * 512; |
585f8587 | 413 | |
7b88e48b | 414 | if (acb->remaining_sectors == 0) { |
585f8587 | 415 | /* request completed */ |
f141eafe AL |
416 | ret = 0; |
417 | goto done; | |
585f8587 | 418 | } |
3b46e624 | 419 | |
585f8587 | 420 | /* prepare next AIO request */ |
7b88e48b | 421 | acb->cur_nr_sectors = acb->remaining_sectors; |
bd28f835 KW |
422 | if (s->crypt_method) { |
423 | acb->cur_nr_sectors = MIN(acb->cur_nr_sectors, | |
424 | QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors); | |
425 | } | |
426 | ||
1c46efaa KW |
427 | ret = qcow2_get_cluster_offset(bs, acb->sector_num << 9, |
428 | &acb->cur_nr_sectors, &acb->cluster_offset); | |
429 | if (ret < 0) { | |
430 | goto done; | |
431 | } | |
432 | ||
ce1a14dc | 433 | index_in_cluster = acb->sector_num & (s->cluster_sectors - 1); |
ce1a14dc | 434 | |
bd28f835 KW |
435 | qemu_iovec_reset(&acb->hd_qiov); |
436 | qemu_iovec_copy(&acb->hd_qiov, acb->qiov, acb->bytes_done, | |
437 | acb->cur_nr_sectors * 512); | |
438 | ||
ce1a14dc | 439 | if (!acb->cluster_offset) { |
bd28f835 | 440 | |
585f8587 FB |
441 | if (bs->backing_hd) { |
442 | /* read from the base image */ | |
bd28f835 KW |
443 | n1 = qcow2_backing_read1(bs->backing_hd, &acb->hd_qiov, |
444 | acb->sector_num, acb->cur_nr_sectors); | |
a9465922 | 445 | if (n1 > 0) { |
66f82cee | 446 | BLKDBG_EVENT(bs->file, BLKDBG_READ_BACKING_AIO); |
c87c0672 | 447 | acb->hd_aiocb = bdrv_aio_readv(bs->backing_hd, acb->sector_num, |
7b88e48b | 448 | &acb->hd_qiov, acb->cur_nr_sectors, |
c87c0672 | 449 | qcow_aio_read_cb, acb); |
ce1a14dc | 450 | if (acb->hd_aiocb == NULL) |
f141eafe | 451 | goto done; |
a9465922 | 452 | } else { |
a32ef786 AL |
453 | ret = qcow_schedule_bh(qcow_aio_read_bh, acb); |
454 | if (ret < 0) | |
f141eafe | 455 | goto done; |
a9465922 | 456 | } |
585f8587 FB |
457 | } else { |
458 | /* Note: in this case, no need to wait */ | |
bd28f835 | 459 | qemu_iovec_memset(&acb->hd_qiov, 0, 512 * acb->cur_nr_sectors); |
a32ef786 AL |
460 | ret = qcow_schedule_bh(qcow_aio_read_bh, acb); |
461 | if (ret < 0) | |
f141eafe | 462 | goto done; |
585f8587 | 463 | } |
ce1a14dc | 464 | } else if (acb->cluster_offset & QCOW_OFLAG_COMPRESSED) { |
585f8587 | 465 | /* add AIO support for compressed blocks ? */ |
66f82cee | 466 | if (qcow2_decompress_cluster(bs, acb->cluster_offset) < 0) |
f141eafe | 467 | goto done; |
bd28f835 KW |
468 | |
469 | qemu_iovec_from_buffer(&acb->hd_qiov, | |
470 | s->cluster_cache + index_in_cluster * 512, | |
471 | 512 * acb->cur_nr_sectors); | |
472 | ||
a32ef786 AL |
473 | ret = qcow_schedule_bh(qcow_aio_read_bh, acb); |
474 | if (ret < 0) | |
f141eafe | 475 | goto done; |
585f8587 | 476 | } else { |
ce1a14dc | 477 | if ((acb->cluster_offset & 511) != 0) { |
585f8587 | 478 | ret = -EIO; |
f141eafe | 479 | goto done; |
585f8587 | 480 | } |
c87c0672 | 481 | |
bd28f835 KW |
482 | if (s->crypt_method) { |
483 | /* | |
484 | * For encrypted images, read everything into a temporary | |
485 | * contiguous buffer on which the AES functions can work. | |
486 | */ | |
487 | if (!acb->cluster_data) { | |
488 | acb->cluster_data = | |
489 | qemu_mallocz(QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size); | |
490 | } | |
491 | ||
492 | assert(acb->cur_nr_sectors <= | |
493 | QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors); | |
494 | qemu_iovec_reset(&acb->hd_qiov); | |
495 | qemu_iovec_add(&acb->hd_qiov, acb->cluster_data, | |
496 | 512 * acb->cur_nr_sectors); | |
497 | } | |
498 | ||
66f82cee KW |
499 | BLKDBG_EVENT(bs->file, BLKDBG_READ_AIO); |
500 | acb->hd_aiocb = bdrv_aio_readv(bs->file, | |
5fafdf24 | 501 | (acb->cluster_offset >> 9) + index_in_cluster, |
7b88e48b CH |
502 | &acb->hd_qiov, acb->cur_nr_sectors, |
503 | qcow_aio_read_cb, acb); | |
171e3d6b KW |
504 | if (acb->hd_aiocb == NULL) { |
505 | ret = -EIO; | |
f141eafe | 506 | goto done; |
171e3d6b | 507 | } |
f141eafe AL |
508 | } |
509 | ||
510 | return; | |
511 | done: | |
f141eafe | 512 | acb->common.cb(acb->common.opaque, ret); |
bd28f835 | 513 | qemu_iovec_destroy(&acb->hd_qiov); |
f141eafe | 514 | qemu_aio_release(acb); |
585f8587 FB |
515 | } |
516 | ||
ce1a14dc | 517 | static QCowAIOCB *qcow_aio_setup(BlockDriverState *bs, |
f141eafe AL |
518 | int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, |
519 | BlockDriverCompletionFunc *cb, void *opaque, int is_write) | |
585f8587 | 520 | { |
ce1a14dc PB |
521 | QCowAIOCB *acb; |
522 | ||
c16b5a2c | 523 | acb = qemu_aio_get(&qcow_aio_pool, bs, cb, opaque); |
ce1a14dc PB |
524 | if (!acb) |
525 | return NULL; | |
526 | acb->hd_aiocb = NULL; | |
527 | acb->sector_num = sector_num; | |
f141eafe | 528 | acb->qiov = qiov; |
bd28f835 | 529 | |
6f5f060b | 530 | qemu_iovec_init(&acb->hd_qiov, qiov->niov); |
bd28f835 KW |
531 | |
532 | acb->bytes_done = 0; | |
7b88e48b CH |
533 | acb->remaining_sectors = nb_sectors; |
534 | acb->cur_nr_sectors = 0; | |
ce1a14dc | 535 | acb->cluster_offset = 0; |
e976c6a1 | 536 | acb->l2meta.nb_clusters = 0; |
72cf2d4f | 537 | QLIST_INIT(&acb->l2meta.dependent_requests); |
ce1a14dc PB |
538 | return acb; |
539 | } | |
540 | ||
f141eafe AL |
541 | static BlockDriverAIOCB *qcow_aio_readv(BlockDriverState *bs, |
542 | int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, | |
ce1a14dc PB |
543 | BlockDriverCompletionFunc *cb, void *opaque) |
544 | { | |
545 | QCowAIOCB *acb; | |
546 | ||
f141eafe | 547 | acb = qcow_aio_setup(bs, sector_num, qiov, nb_sectors, cb, opaque, 0); |
ce1a14dc PB |
548 | if (!acb) |
549 | return NULL; | |
585f8587 FB |
550 | |
551 | qcow_aio_read_cb(acb, 0); | |
ce1a14dc | 552 | return &acb->common; |
585f8587 FB |
553 | } |
554 | ||
f214978a KW |
555 | static void qcow_aio_write_cb(void *opaque, int ret); |
556 | ||
557 | static void run_dependent_requests(QCowL2Meta *m) | |
558 | { | |
559 | QCowAIOCB *req; | |
560 | QCowAIOCB *next; | |
561 | ||
562 | /* Take the request off the list of running requests */ | |
563 | if (m->nb_clusters != 0) { | |
72cf2d4f | 564 | QLIST_REMOVE(m, next_in_flight); |
f214978a KW |
565 | } |
566 | ||
d4c146f0 SH |
567 | /* Restart all dependent requests */ |
568 | QLIST_FOREACH_SAFE(req, &m->dependent_requests, next_depend, next) { | |
f214978a KW |
569 | qcow_aio_write_cb(req, 0); |
570 | } | |
571 | ||
572 | /* Empty the list for the next part of the request */ | |
72cf2d4f | 573 | QLIST_INIT(&m->dependent_requests); |
f214978a KW |
574 | } |
575 | ||
585f8587 FB |
576 | static void qcow_aio_write_cb(void *opaque, int ret) |
577 | { | |
ce1a14dc PB |
578 | QCowAIOCB *acb = opaque; |
579 | BlockDriverState *bs = acb->common.bs; | |
585f8587 | 580 | BDRVQcowState *s = bs->opaque; |
585f8587 | 581 | int index_in_cluster; |
095a9c58 | 582 | int n_end; |
ce1a14dc PB |
583 | |
584 | acb->hd_aiocb = NULL; | |
585 | ||
f214978a | 586 | if (ret >= 0) { |
148da7ea | 587 | ret = qcow2_alloc_cluster_link_l2(bs, &acb->l2meta); |
f214978a KW |
588 | } |
589 | ||
590 | run_dependent_requests(&acb->l2meta); | |
591 | ||
f141eafe AL |
592 | if (ret < 0) |
593 | goto done; | |
585f8587 | 594 | |
7b88e48b CH |
595 | acb->remaining_sectors -= acb->cur_nr_sectors; |
596 | acb->sector_num += acb->cur_nr_sectors; | |
6f5f060b | 597 | acb->bytes_done += acb->cur_nr_sectors * 512; |
585f8587 | 598 | |
7b88e48b | 599 | if (acb->remaining_sectors == 0) { |
585f8587 | 600 | /* request completed */ |
f141eafe AL |
601 | ret = 0; |
602 | goto done; | |
585f8587 | 603 | } |
3b46e624 | 604 | |
ce1a14dc | 605 | index_in_cluster = acb->sector_num & (s->cluster_sectors - 1); |
7b88e48b | 606 | n_end = index_in_cluster + acb->remaining_sectors; |
095a9c58 AL |
607 | if (s->crypt_method && |
608 | n_end > QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors) | |
609 | n_end = QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors; | |
610 | ||
148da7ea | 611 | ret = qcow2_alloc_cluster_offset(bs, acb->sector_num << 9, |
7b88e48b | 612 | index_in_cluster, n_end, &acb->cur_nr_sectors, &acb->l2meta); |
148da7ea KW |
613 | if (ret < 0) { |
614 | goto done; | |
615 | } | |
616 | ||
617 | acb->cluster_offset = acb->l2meta.cluster_offset; | |
f214978a KW |
618 | |
619 | /* Need to wait for another request? If so, we are done for now. */ | |
148da7ea | 620 | if (acb->l2meta.nb_clusters == 0 && acb->l2meta.depends_on != NULL) { |
72cf2d4f | 621 | QLIST_INSERT_HEAD(&acb->l2meta.depends_on->dependent_requests, |
f214978a KW |
622 | acb, next_depend); |
623 | return; | |
624 | } | |
625 | ||
148da7ea KW |
626 | assert((acb->cluster_offset & 511) == 0); |
627 | ||
6f5f060b KW |
628 | qemu_iovec_reset(&acb->hd_qiov); |
629 | qemu_iovec_copy(&acb->hd_qiov, acb->qiov, acb->bytes_done, | |
630 | acb->cur_nr_sectors * 512); | |
631 | ||
585f8587 | 632 | if (s->crypt_method) { |
ce1a14dc | 633 | if (!acb->cluster_data) { |
095a9c58 AL |
634 | acb->cluster_data = qemu_mallocz(QCOW_MAX_CRYPT_CLUSTERS * |
635 | s->cluster_size); | |
585f8587 | 636 | } |
6f5f060b KW |
637 | |
638 | assert(acb->hd_qiov.size <= QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size); | |
639 | qemu_iovec_to_buffer(&acb->hd_qiov, acb->cluster_data); | |
640 | ||
641 | qcow2_encrypt_sectors(s, acb->sector_num, acb->cluster_data, | |
642 | acb->cluster_data, acb->cur_nr_sectors, 1, &s->aes_encrypt_key); | |
643 | ||
644 | qemu_iovec_reset(&acb->hd_qiov); | |
645 | qemu_iovec_add(&acb->hd_qiov, acb->cluster_data, | |
646 | acb->cur_nr_sectors * 512); | |
585f8587 | 647 | } |
6f5f060b | 648 | |
66f82cee KW |
649 | BLKDBG_EVENT(bs->file, BLKDBG_WRITE_AIO); |
650 | acb->hd_aiocb = bdrv_aio_writev(bs->file, | |
c87c0672 | 651 | (acb->cluster_offset >> 9) + index_in_cluster, |
7b88e48b | 652 | &acb->hd_qiov, acb->cur_nr_sectors, |
c87c0672 | 653 | qcow_aio_write_cb, acb); |
171e3d6b KW |
654 | if (acb->hd_aiocb == NULL) { |
655 | ret = -EIO; | |
c644db3d | 656 | goto fail; |
171e3d6b | 657 | } |
f141eafe AL |
658 | |
659 | return; | |
660 | ||
c644db3d KW |
661 | fail: |
662 | if (acb->l2meta.nb_clusters != 0) { | |
663 | QLIST_REMOVE(&acb->l2meta, next_in_flight); | |
664 | } | |
f141eafe | 665 | done: |
f141eafe | 666 | acb->common.cb(acb->common.opaque, ret); |
6f5f060b | 667 | qemu_iovec_destroy(&acb->hd_qiov); |
f141eafe | 668 | qemu_aio_release(acb); |
585f8587 FB |
669 | } |
670 | ||
f141eafe AL |
671 | static BlockDriverAIOCB *qcow_aio_writev(BlockDriverState *bs, |
672 | int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, | |
ce1a14dc | 673 | BlockDriverCompletionFunc *cb, void *opaque) |
585f8587 | 674 | { |
585f8587 | 675 | BDRVQcowState *s = bs->opaque; |
ce1a14dc | 676 | QCowAIOCB *acb; |
3b46e624 | 677 | |
585f8587 FB |
678 | s->cluster_cache_offset = -1; /* disable compressed cache */ |
679 | ||
f141eafe | 680 | acb = qcow_aio_setup(bs, sector_num, qiov, nb_sectors, cb, opaque, 1); |
ce1a14dc PB |
681 | if (!acb) |
682 | return NULL; | |
3b46e624 | 683 | |
585f8587 | 684 | qcow_aio_write_cb(acb, 0); |
ce1a14dc | 685 | return &acb->common; |
585f8587 FB |
686 | } |
687 | ||
585f8587 FB |
688 | static void qcow_close(BlockDriverState *bs) |
689 | { | |
690 | BDRVQcowState *s = bs->opaque; | |
691 | qemu_free(s->l1_table); | |
692 | qemu_free(s->l2_cache); | |
693 | qemu_free(s->cluster_cache); | |
694 | qemu_free(s->cluster_data); | |
ed6ccf0f | 695 | qcow2_refcount_close(bs); |
585f8587 FB |
696 | } |
697 | ||
756e6736 KW |
698 | /* |
699 | * Updates the variable length parts of the qcow2 header, i.e. the backing file | |
700 | * name and all extensions. qcow2 was not designed to allow such changes, so if | |
701 | * we run out of space (we can only use the first cluster) this function may | |
702 | * fail. | |
703 | * | |
704 | * Returns 0 on success, -errno in error cases. | |
705 | */ | |
706 | static int qcow2_update_ext_header(BlockDriverState *bs, | |
707 | const char *backing_file, const char *backing_fmt) | |
708 | { | |
709 | size_t backing_file_len = 0; | |
710 | size_t backing_fmt_len = 0; | |
711 | BDRVQcowState *s = bs->opaque; | |
712 | QCowExtension ext_backing_fmt = {0, 0}; | |
713 | int ret; | |
714 | ||
715 | /* Backing file format doesn't make sense without a backing file */ | |
716 | if (backing_fmt && !backing_file) { | |
717 | return -EINVAL; | |
718 | } | |
719 | ||
720 | /* Prepare the backing file format extension if needed */ | |
721 | if (backing_fmt) { | |
722 | ext_backing_fmt.len = cpu_to_be32(strlen(backing_fmt)); | |
723 | ext_backing_fmt.magic = cpu_to_be32(QCOW_EXT_MAGIC_BACKING_FORMAT); | |
724 | backing_fmt_len = ((sizeof(ext_backing_fmt) | |
725 | + strlen(backing_fmt) + 7) & ~7); | |
726 | } | |
727 | ||
728 | /* Check if we can fit the new header into the first cluster */ | |
729 | if (backing_file) { | |
730 | backing_file_len = strlen(backing_file); | |
731 | } | |
732 | ||
733 | size_t header_size = sizeof(QCowHeader) + backing_file_len | |
734 | + backing_fmt_len; | |
735 | ||
736 | if (header_size > s->cluster_size) { | |
737 | return -ENOSPC; | |
738 | } | |
739 | ||
740 | /* Rewrite backing file name and qcow2 extensions */ | |
741 | size_t ext_size = header_size - sizeof(QCowHeader); | |
742 | uint8_t buf[ext_size]; | |
743 | size_t offset = 0; | |
744 | size_t backing_file_offset = 0; | |
745 | ||
746 | if (backing_file) { | |
747 | if (backing_fmt) { | |
748 | int padding = backing_fmt_len - | |
749 | (sizeof(ext_backing_fmt) + strlen(backing_fmt)); | |
750 | ||
751 | memcpy(buf + offset, &ext_backing_fmt, sizeof(ext_backing_fmt)); | |
752 | offset += sizeof(ext_backing_fmt); | |
753 | ||
754 | memcpy(buf + offset, backing_fmt, strlen(backing_fmt)); | |
755 | offset += strlen(backing_fmt); | |
756 | ||
757 | memset(buf + offset, 0, padding); | |
758 | offset += padding; | |
759 | } | |
760 | ||
761 | memcpy(buf + offset, backing_file, backing_file_len); | |
762 | backing_file_offset = sizeof(QCowHeader) + offset; | |
763 | } | |
764 | ||
8b3b7206 | 765 | ret = bdrv_pwrite_sync(bs->file, sizeof(QCowHeader), buf, ext_size); |
756e6736 KW |
766 | if (ret < 0) { |
767 | goto fail; | |
768 | } | |
769 | ||
770 | /* Update header fields */ | |
771 | uint64_t be_backing_file_offset = cpu_to_be64(backing_file_offset); | |
772 | uint32_t be_backing_file_size = cpu_to_be32(backing_file_len); | |
773 | ||
8b3b7206 | 774 | ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, backing_file_offset), |
756e6736 KW |
775 | &be_backing_file_offset, sizeof(uint64_t)); |
776 | if (ret < 0) { | |
777 | goto fail; | |
778 | } | |
779 | ||
8b3b7206 | 780 | ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, backing_file_size), |
756e6736 KW |
781 | &be_backing_file_size, sizeof(uint32_t)); |
782 | if (ret < 0) { | |
783 | goto fail; | |
784 | } | |
785 | ||
786 | ret = 0; | |
787 | fail: | |
788 | return ret; | |
789 | } | |
790 | ||
791 | static int qcow2_change_backing_file(BlockDriverState *bs, | |
792 | const char *backing_file, const char *backing_fmt) | |
793 | { | |
794 | return qcow2_update_ext_header(bs, backing_file, backing_fmt); | |
795 | } | |
796 | ||
73c632ed KW |
797 | static int get_bits_from_size(size_t size) |
798 | { | |
799 | int res = 0; | |
800 | ||
801 | if (size == 0) { | |
802 | return -1; | |
803 | } | |
804 | ||
805 | while (size != 1) { | |
806 | /* Not a power of two */ | |
807 | if (size & 1) { | |
808 | return -1; | |
809 | } | |
810 | ||
811 | size >>= 1; | |
812 | res++; | |
813 | } | |
814 | ||
815 | return res; | |
816 | } | |
817 | ||
a35e1c17 KW |
818 | |
819 | static int preallocate(BlockDriverState *bs) | |
820 | { | |
a35e1c17 KW |
821 | uint64_t nb_sectors; |
822 | uint64_t offset; | |
823 | int num; | |
148da7ea | 824 | int ret; |
a35e1c17 KW |
825 | QCowL2Meta meta; |
826 | ||
827 | nb_sectors = bdrv_getlength(bs) >> 9; | |
828 | offset = 0; | |
72cf2d4f | 829 | QLIST_INIT(&meta.dependent_requests); |
148da7ea | 830 | meta.cluster_offset = 0; |
a35e1c17 KW |
831 | |
832 | while (nb_sectors) { | |
833 | num = MIN(nb_sectors, INT_MAX >> 9); | |
148da7ea | 834 | ret = qcow2_alloc_cluster_offset(bs, offset, 0, num, &num, &meta); |
148da7ea | 835 | if (ret < 0) { |
19dbcbf7 | 836 | return ret; |
a35e1c17 KW |
837 | } |
838 | ||
19dbcbf7 KW |
839 | ret = qcow2_alloc_cluster_link_l2(bs, &meta); |
840 | if (ret < 0) { | |
148da7ea | 841 | qcow2_free_any_clusters(bs, meta.cluster_offset, meta.nb_clusters); |
19dbcbf7 | 842 | return ret; |
a35e1c17 KW |
843 | } |
844 | ||
f214978a KW |
845 | /* There are no dependent requests, but we need to remove our request |
846 | * from the list of in-flight requests */ | |
847 | run_dependent_requests(&meta); | |
848 | ||
a35e1c17 KW |
849 | /* TODO Preallocate data if requested */ |
850 | ||
851 | nb_sectors -= num; | |
852 | offset += num << 9; | |
853 | } | |
854 | ||
855 | /* | |
856 | * It is expected that the image file is large enough to actually contain | |
857 | * all of the allocated clusters (otherwise we get failing reads after | |
858 | * EOF). Extend the image to the last allocated sector. | |
859 | */ | |
148da7ea | 860 | if (meta.cluster_offset != 0) { |
ea80b906 KW |
861 | uint8_t buf[512]; |
862 | memset(buf, 0, 512); | |
19dbcbf7 KW |
863 | ret = bdrv_write(bs->file, (meta.cluster_offset >> 9) + num - 1, buf, 1); |
864 | if (ret < 0) { | |
865 | return ret; | |
866 | } | |
a35e1c17 KW |
867 | } |
868 | ||
869 | return 0; | |
870 | } | |
871 | ||
de5f3f40 KW |
872 | static int qcow_create2(const char *filename, int64_t total_size, |
873 | const char *backing_file, const char *backing_format, | |
874 | int flags, size_t cluster_size, int prealloc) | |
875 | { | |
876 | ||
877 | int fd, header_size, backing_filename_len, l1_size, i, shift, l2_bits; | |
878 | int ref_clusters, reftable_clusters, backing_format_len = 0; | |
879 | int rounded_ext_bf_len = 0; | |
880 | QCowHeader header; | |
881 | uint64_t tmp, offset; | |
882 | uint64_t old_ref_clusters; | |
883 | QCowCreateState s1, *s = &s1; | |
884 | QCowExtension ext_bf = {0, 0}; | |
885 | int ret; | |
886 | ||
887 | memset(s, 0, sizeof(*s)); | |
888 | ||
889 | fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, 0644); | |
890 | if (fd < 0) | |
891 | return -errno; | |
892 | memset(&header, 0, sizeof(header)); | |
893 | header.magic = cpu_to_be32(QCOW_MAGIC); | |
894 | header.version = cpu_to_be32(QCOW_VERSION); | |
895 | header.size = cpu_to_be64(total_size * 512); | |
896 | header_size = sizeof(header); | |
897 | backing_filename_len = 0; | |
898 | if (backing_file) { | |
899 | if (backing_format) { | |
900 | ext_bf.magic = QCOW_EXT_MAGIC_BACKING_FORMAT; | |
901 | backing_format_len = strlen(backing_format); | |
902 | ext_bf.len = backing_format_len; | |
903 | rounded_ext_bf_len = (sizeof(ext_bf) + ext_bf.len + 7) & ~7; | |
904 | header_size += rounded_ext_bf_len; | |
905 | } | |
906 | header.backing_file_offset = cpu_to_be64(header_size); | |
907 | backing_filename_len = strlen(backing_file); | |
908 | header.backing_file_size = cpu_to_be32(backing_filename_len); | |
909 | header_size += backing_filename_len; | |
910 | } | |
911 | ||
912 | /* Cluster size */ | |
913 | s->cluster_bits = get_bits_from_size(cluster_size); | |
914 | if (s->cluster_bits < MIN_CLUSTER_BITS || | |
915 | s->cluster_bits > MAX_CLUSTER_BITS) | |
916 | { | |
917 | fprintf(stderr, "Cluster size must be a power of two between " | |
918 | "%d and %dk\n", | |
919 | 1 << MIN_CLUSTER_BITS, | |
920 | 1 << (MAX_CLUSTER_BITS - 10)); | |
921 | return -EINVAL; | |
922 | } | |
923 | s->cluster_size = 1 << s->cluster_bits; | |
924 | ||
925 | header.cluster_bits = cpu_to_be32(s->cluster_bits); | |
926 | header_size = (header_size + 7) & ~7; | |
927 | if (flags & BLOCK_FLAG_ENCRYPT) { | |
928 | header.crypt_method = cpu_to_be32(QCOW_CRYPT_AES); | |
929 | } else { | |
930 | header.crypt_method = cpu_to_be32(QCOW_CRYPT_NONE); | |
931 | } | |
932 | l2_bits = s->cluster_bits - 3; | |
933 | shift = s->cluster_bits + l2_bits; | |
934 | l1_size = (((total_size * 512) + (1LL << shift) - 1) >> shift); | |
935 | offset = align_offset(header_size, s->cluster_size); | |
936 | s->l1_table_offset = offset; | |
937 | header.l1_table_offset = cpu_to_be64(s->l1_table_offset); | |
938 | header.l1_size = cpu_to_be32(l1_size); | |
939 | offset += align_offset(l1_size * sizeof(uint64_t), s->cluster_size); | |
940 | ||
941 | /* count how many refcount blocks needed */ | |
942 | ||
943 | #define NUM_CLUSTERS(bytes) \ | |
944 | (((bytes) + (s->cluster_size) - 1) / (s->cluster_size)) | |
945 | ||
946 | ref_clusters = NUM_CLUSTERS(NUM_CLUSTERS(offset) * sizeof(uint16_t)); | |
947 | ||
948 | do { | |
949 | uint64_t image_clusters; | |
950 | old_ref_clusters = ref_clusters; | |
951 | ||
952 | /* Number of clusters used for the refcount table */ | |
953 | reftable_clusters = NUM_CLUSTERS(ref_clusters * sizeof(uint64_t)); | |
954 | ||
955 | /* Number of clusters that the whole image will have */ | |
956 | image_clusters = NUM_CLUSTERS(offset) + ref_clusters | |
957 | + reftable_clusters; | |
958 | ||
959 | /* Number of refcount blocks needed for the image */ | |
960 | ref_clusters = NUM_CLUSTERS(image_clusters * sizeof(uint16_t)); | |
961 | ||
962 | } while (ref_clusters != old_ref_clusters); | |
963 | ||
964 | s->refcount_table = qemu_mallocz(reftable_clusters * s->cluster_size); | |
965 | ||
966 | s->refcount_table_offset = offset; | |
967 | header.refcount_table_offset = cpu_to_be64(offset); | |
968 | header.refcount_table_clusters = cpu_to_be32(reftable_clusters); | |
969 | offset += (reftable_clusters * s->cluster_size); | |
970 | s->refcount_block_offset = offset; | |
971 | ||
972 | for (i=0; i < ref_clusters; i++) { | |
973 | s->refcount_table[i] = cpu_to_be64(offset); | |
974 | offset += s->cluster_size; | |
975 | } | |
976 | ||
977 | s->refcount_block = qemu_mallocz(ref_clusters * s->cluster_size); | |
978 | ||
979 | /* update refcounts */ | |
980 | qcow2_create_refcount_update(s, 0, header_size); | |
981 | qcow2_create_refcount_update(s, s->l1_table_offset, | |
982 | l1_size * sizeof(uint64_t)); | |
983 | qcow2_create_refcount_update(s, s->refcount_table_offset, | |
984 | reftable_clusters * s->cluster_size); | |
985 | qcow2_create_refcount_update(s, s->refcount_block_offset, | |
986 | ref_clusters * s->cluster_size); | |
987 | ||
988 | /* write all the data */ | |
989 | ret = qemu_write_full(fd, &header, sizeof(header)); | |
990 | if (ret != sizeof(header)) { | |
991 | ret = -errno; | |
992 | goto exit; | |
993 | } | |
994 | if (backing_file) { | |
995 | if (backing_format_len) { | |
996 | char zero[16]; | |
997 | int padding = rounded_ext_bf_len - (ext_bf.len + sizeof(ext_bf)); | |
998 | ||
999 | memset(zero, 0, sizeof(zero)); | |
1000 | cpu_to_be32s(&ext_bf.magic); | |
1001 | cpu_to_be32s(&ext_bf.len); | |
1002 | ret = qemu_write_full(fd, &ext_bf, sizeof(ext_bf)); | |
1003 | if (ret != sizeof(ext_bf)) { | |
1004 | ret = -errno; | |
1005 | goto exit; | |
1006 | } | |
1007 | ret = qemu_write_full(fd, backing_format, backing_format_len); | |
1008 | if (ret != backing_format_len) { | |
1009 | ret = -errno; | |
1010 | goto exit; | |
1011 | } | |
1012 | if (padding > 0) { | |
1013 | ret = qemu_write_full(fd, zero, padding); | |
1014 | if (ret != padding) { | |
1015 | ret = -errno; | |
1016 | goto exit; | |
1017 | } | |
1018 | } | |
1019 | } | |
1020 | ret = qemu_write_full(fd, backing_file, backing_filename_len); | |
1021 | if (ret != backing_filename_len) { | |
1022 | ret = -errno; | |
1023 | goto exit; | |
1024 | } | |
1025 | } | |
1026 | lseek(fd, s->l1_table_offset, SEEK_SET); | |
1027 | tmp = 0; | |
1028 | for(i = 0;i < l1_size; i++) { | |
1029 | ret = qemu_write_full(fd, &tmp, sizeof(tmp)); | |
1030 | if (ret != sizeof(tmp)) { | |
1031 | ret = -errno; | |
1032 | goto exit; | |
1033 | } | |
1034 | } | |
1035 | lseek(fd, s->refcount_table_offset, SEEK_SET); | |
1036 | ret = qemu_write_full(fd, s->refcount_table, | |
1037 | reftable_clusters * s->cluster_size); | |
1038 | if (ret != reftable_clusters * s->cluster_size) { | |
1039 | ret = -errno; | |
1040 | goto exit; | |
1041 | } | |
1042 | ||
1043 | lseek(fd, s->refcount_block_offset, SEEK_SET); | |
1044 | ret = qemu_write_full(fd, s->refcount_block, | |
1045 | ref_clusters * s->cluster_size); | |
1046 | if (ret != ref_clusters * s->cluster_size) { | |
1047 | ret = -errno; | |
1048 | goto exit; | |
1049 | } | |
1050 | ||
1051 | ret = 0; | |
1052 | exit: | |
1053 | qemu_free(s->refcount_table); | |
1054 | qemu_free(s->refcount_block); | |
1055 | close(fd); | |
1056 | ||
1057 | /* Preallocate metadata */ | |
1058 | if (ret == 0 && prealloc) { | |
1059 | BlockDriverState *bs; | |
92b30744 | 1060 | BlockDriver *drv = bdrv_find_format("qcow2"); |
de5f3f40 | 1061 | bs = bdrv_new(""); |
92b30744 | 1062 | bdrv_open(bs, filename, BDRV_O_CACHE_WB | BDRV_O_RDWR, drv); |
19dbcbf7 | 1063 | ret = preallocate(bs); |
de5f3f40 KW |
1064 | bdrv_close(bs); |
1065 | } | |
1066 | ||
1067 | return ret; | |
1068 | } | |
1069 | ||
1070 | static int qcow_create(const char *filename, QEMUOptionParameter *options) | |
1071 | { | |
1072 | const char *backing_file = NULL; | |
1073 | const char *backing_fmt = NULL; | |
1074 | uint64_t sectors = 0; | |
1075 | int flags = 0; | |
1076 | size_t cluster_size = 65536; | |
1077 | int prealloc = 0; | |
1078 | ||
1079 | /* Read out options */ | |
1080 | while (options && options->name) { | |
1081 | if (!strcmp(options->name, BLOCK_OPT_SIZE)) { | |
1082 | sectors = options->value.n / 512; | |
1083 | } else if (!strcmp(options->name, BLOCK_OPT_BACKING_FILE)) { | |
1084 | backing_file = options->value.s; | |
1085 | } else if (!strcmp(options->name, BLOCK_OPT_BACKING_FMT)) { | |
1086 | backing_fmt = options->value.s; | |
1087 | } else if (!strcmp(options->name, BLOCK_OPT_ENCRYPT)) { | |
1088 | flags |= options->value.n ? BLOCK_FLAG_ENCRYPT : 0; | |
1089 | } else if (!strcmp(options->name, BLOCK_OPT_CLUSTER_SIZE)) { | |
1090 | if (options->value.n) { | |
1091 | cluster_size = options->value.n; | |
1092 | } | |
1093 | } else if (!strcmp(options->name, BLOCK_OPT_PREALLOC)) { | |
1094 | if (!options->value.s || !strcmp(options->value.s, "off")) { | |
1095 | prealloc = 0; | |
1096 | } else if (!strcmp(options->value.s, "metadata")) { | |
1097 | prealloc = 1; | |
1098 | } else { | |
1099 | fprintf(stderr, "Invalid preallocation mode: '%s'\n", | |
1100 | options->value.s); | |
1101 | return -EINVAL; | |
1102 | } | |
1103 | } | |
1104 | options++; | |
1105 | } | |
1106 | ||
1107 | if (backing_file && prealloc) { | |
1108 | fprintf(stderr, "Backing file and preallocation cannot be used at " | |
1109 | "the same time\n"); | |
1110 | return -EINVAL; | |
1111 | } | |
1112 | ||
1113 | return qcow_create2(filename, sectors, backing_file, backing_fmt, flags, | |
1114 | cluster_size, prealloc); | |
1115 | } | |
1116 | ||
20d97356 BS |
1117 | static int qcow_make_empty(BlockDriverState *bs) |
1118 | { | |
1119 | #if 0 | |
1120 | /* XXX: not correct */ | |
1121 | BDRVQcowState *s = bs->opaque; | |
1122 | uint32_t l1_length = s->l1_size * sizeof(uint64_t); | |
1123 | int ret; | |
1124 | ||
1125 | memset(s->l1_table, 0, l1_length); | |
66f82cee | 1126 | if (bdrv_pwrite(bs->file, s->l1_table_offset, s->l1_table, l1_length) < 0) |
20d97356 | 1127 | return -1; |
66f82cee | 1128 | ret = bdrv_truncate(bs->file, s->l1_table_offset + l1_length); |
20d97356 BS |
1129 | if (ret < 0) |
1130 | return ret; | |
1131 | ||
1132 | l2_cache_reset(bs); | |
1133 | #endif | |
1134 | return 0; | |
1135 | } | |
1136 | ||
419b19d9 SH |
1137 | static int qcow2_truncate(BlockDriverState *bs, int64_t offset) |
1138 | { | |
1139 | BDRVQcowState *s = bs->opaque; | |
1140 | int ret, new_l1_size; | |
1141 | ||
1142 | if (offset & 511) { | |
1143 | return -EINVAL; | |
1144 | } | |
1145 | ||
1146 | /* cannot proceed if image has snapshots */ | |
1147 | if (s->nb_snapshots) { | |
1148 | return -ENOTSUP; | |
1149 | } | |
1150 | ||
1151 | /* shrinking is currently not supported */ | |
1152 | if (offset < bs->total_sectors * 512) { | |
1153 | return -ENOTSUP; | |
1154 | } | |
1155 | ||
1156 | new_l1_size = size_to_l1(s, offset); | |
1157 | ret = qcow2_grow_l1_table(bs, new_l1_size); | |
1158 | if (ret < 0) { | |
1159 | return ret; | |
1160 | } | |
1161 | ||
1162 | /* write updated header.size */ | |
1163 | offset = cpu_to_be64(offset); | |
8b3b7206 KW |
1164 | ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, size), |
1165 | &offset, sizeof(uint64_t)); | |
419b19d9 SH |
1166 | if (ret < 0) { |
1167 | return ret; | |
1168 | } | |
1169 | ||
1170 | s->l1_vm_state_index = new_l1_size; | |
1171 | return 0; | |
1172 | } | |
1173 | ||
20d97356 BS |
1174 | /* XXX: put compressed sectors first, then all the cluster aligned |
1175 | tables to avoid losing bytes in alignment */ | |
1176 | static int qcow_write_compressed(BlockDriverState *bs, int64_t sector_num, | |
1177 | const uint8_t *buf, int nb_sectors) | |
1178 | { | |
1179 | BDRVQcowState *s = bs->opaque; | |
1180 | z_stream strm; | |
1181 | int ret, out_len; | |
1182 | uint8_t *out_buf; | |
1183 | uint64_t cluster_offset; | |
1184 | ||
1185 | if (nb_sectors == 0) { | |
1186 | /* align end of file to a sector boundary to ease reading with | |
1187 | sector based I/Os */ | |
66f82cee | 1188 | cluster_offset = bdrv_getlength(bs->file); |
20d97356 | 1189 | cluster_offset = (cluster_offset + 511) & ~511; |
66f82cee | 1190 | bdrv_truncate(bs->file, cluster_offset); |
20d97356 BS |
1191 | return 0; |
1192 | } | |
1193 | ||
1194 | if (nb_sectors != s->cluster_sectors) | |
1195 | return -EINVAL; | |
1196 | ||
1197 | out_buf = qemu_malloc(s->cluster_size + (s->cluster_size / 1000) + 128); | |
1198 | ||
1199 | /* best compression, small window, no zlib header */ | |
1200 | memset(&strm, 0, sizeof(strm)); | |
1201 | ret = deflateInit2(&strm, Z_DEFAULT_COMPRESSION, | |
1202 | Z_DEFLATED, -12, | |
1203 | 9, Z_DEFAULT_STRATEGY); | |
1204 | if (ret != 0) { | |
1205 | qemu_free(out_buf); | |
1206 | return -1; | |
1207 | } | |
1208 | ||
1209 | strm.avail_in = s->cluster_size; | |
1210 | strm.next_in = (uint8_t *)buf; | |
1211 | strm.avail_out = s->cluster_size; | |
1212 | strm.next_out = out_buf; | |
1213 | ||
1214 | ret = deflate(&strm, Z_FINISH); | |
1215 | if (ret != Z_STREAM_END && ret != Z_OK) { | |
1216 | qemu_free(out_buf); | |
1217 | deflateEnd(&strm); | |
1218 | return -1; | |
1219 | } | |
1220 | out_len = strm.next_out - out_buf; | |
1221 | ||
1222 | deflateEnd(&strm); | |
1223 | ||
1224 | if (ret != Z_STREAM_END || out_len >= s->cluster_size) { | |
1225 | /* could not compress: write normal cluster */ | |
1226 | bdrv_write(bs, sector_num, buf, s->cluster_sectors); | |
1227 | } else { | |
1228 | cluster_offset = qcow2_alloc_compressed_cluster_offset(bs, | |
1229 | sector_num << 9, out_len); | |
1230 | if (!cluster_offset) | |
1231 | return -1; | |
1232 | cluster_offset &= s->cluster_offset_mask; | |
66f82cee KW |
1233 | BLKDBG_EVENT(bs->file, BLKDBG_WRITE_COMPRESSED); |
1234 | if (bdrv_pwrite(bs->file, cluster_offset, out_buf, out_len) != out_len) { | |
20d97356 BS |
1235 | qemu_free(out_buf); |
1236 | return -1; | |
1237 | } | |
1238 | } | |
1239 | ||
1240 | qemu_free(out_buf); | |
1241 | return 0; | |
1242 | } | |
1243 | ||
1244 | static void qcow_flush(BlockDriverState *bs) | |
1245 | { | |
66f82cee | 1246 | bdrv_flush(bs->file); |
20d97356 BS |
1247 | } |
1248 | ||
1249 | static BlockDriverAIOCB *qcow_aio_flush(BlockDriverState *bs, | |
1250 | BlockDriverCompletionFunc *cb, void *opaque) | |
1251 | { | |
66f82cee | 1252 | return bdrv_aio_flush(bs->file, cb, opaque); |
20d97356 BS |
1253 | } |
1254 | ||
1255 | static int64_t qcow_vm_state_offset(BDRVQcowState *s) | |
1256 | { | |
1257 | return (int64_t)s->l1_vm_state_index << (s->cluster_bits + s->l2_bits); | |
1258 | } | |
1259 | ||
1260 | static int qcow_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) | |
1261 | { | |
1262 | BDRVQcowState *s = bs->opaque; | |
1263 | bdi->cluster_size = s->cluster_size; | |
1264 | bdi->vm_state_offset = qcow_vm_state_offset(s); | |
1265 | return 0; | |
1266 | } | |
1267 | ||
1268 | ||
9ac228e0 | 1269 | static int qcow_check(BlockDriverState *bs, BdrvCheckResult *result) |
20d97356 | 1270 | { |
9ac228e0 | 1271 | return qcow2_check_refcounts(bs, result); |
20d97356 BS |
1272 | } |
1273 | ||
1274 | #if 0 | |
1275 | static void dump_refcounts(BlockDriverState *bs) | |
1276 | { | |
1277 | BDRVQcowState *s = bs->opaque; | |
1278 | int64_t nb_clusters, k, k1, size; | |
1279 | int refcount; | |
1280 | ||
66f82cee | 1281 | size = bdrv_getlength(bs->file); |
20d97356 BS |
1282 | nb_clusters = size_to_clusters(s, size); |
1283 | for(k = 0; k < nb_clusters;) { | |
1284 | k1 = k; | |
1285 | refcount = get_refcount(bs, k); | |
1286 | k++; | |
1287 | while (k < nb_clusters && get_refcount(bs, k) == refcount) | |
1288 | k++; | |
0bfcd599 BS |
1289 | printf("%" PRId64 ": refcount=%d nb=%" PRId64 "\n", k, refcount, |
1290 | k - k1); | |
20d97356 BS |
1291 | } |
1292 | } | |
1293 | #endif | |
1294 | ||
1295 | static int qcow_save_vmstate(BlockDriverState *bs, const uint8_t *buf, | |
1296 | int64_t pos, int size) | |
1297 | { | |
1298 | BDRVQcowState *s = bs->opaque; | |
1299 | int growable = bs->growable; | |
1300 | int ret; | |
1301 | ||
66f82cee | 1302 | BLKDBG_EVENT(bs->file, BLKDBG_VMSTATE_SAVE); |
20d97356 BS |
1303 | bs->growable = 1; |
1304 | ret = bdrv_pwrite(bs, qcow_vm_state_offset(s) + pos, buf, size); | |
1305 | bs->growable = growable; | |
1306 | ||
1307 | return ret; | |
1308 | } | |
1309 | ||
1310 | static int qcow_load_vmstate(BlockDriverState *bs, uint8_t *buf, | |
1311 | int64_t pos, int size) | |
1312 | { | |
1313 | BDRVQcowState *s = bs->opaque; | |
1314 | int growable = bs->growable; | |
1315 | int ret; | |
1316 | ||
66f82cee | 1317 | BLKDBG_EVENT(bs->file, BLKDBG_VMSTATE_LOAD); |
20d97356 BS |
1318 | bs->growable = 1; |
1319 | ret = bdrv_pread(bs, qcow_vm_state_offset(s) + pos, buf, size); | |
1320 | bs->growable = growable; | |
1321 | ||
1322 | return ret; | |
1323 | } | |
1324 | ||
1325 | static QEMUOptionParameter qcow_create_options[] = { | |
1326 | { | |
1327 | .name = BLOCK_OPT_SIZE, | |
1328 | .type = OPT_SIZE, | |
1329 | .help = "Virtual disk size" | |
1330 | }, | |
1331 | { | |
1332 | .name = BLOCK_OPT_BACKING_FILE, | |
1333 | .type = OPT_STRING, | |
1334 | .help = "File name of a base image" | |
1335 | }, | |
1336 | { | |
1337 | .name = BLOCK_OPT_BACKING_FMT, | |
1338 | .type = OPT_STRING, | |
1339 | .help = "Image format of the base image" | |
1340 | }, | |
1341 | { | |
1342 | .name = BLOCK_OPT_ENCRYPT, | |
1343 | .type = OPT_FLAG, | |
1344 | .help = "Encrypt the image" | |
1345 | }, | |
1346 | { | |
1347 | .name = BLOCK_OPT_CLUSTER_SIZE, | |
1348 | .type = OPT_SIZE, | |
1349 | .help = "qcow2 cluster size" | |
1350 | }, | |
1351 | { | |
1352 | .name = BLOCK_OPT_PREALLOC, | |
1353 | .type = OPT_STRING, | |
1354 | .help = "Preallocation mode (allowed values: off, metadata)" | |
1355 | }, | |
1356 | { NULL } | |
1357 | }; | |
1358 | ||
1359 | static BlockDriver bdrv_qcow2 = { | |
1360 | .format_name = "qcow2", | |
1361 | .instance_size = sizeof(BDRVQcowState), | |
1362 | .bdrv_probe = qcow_probe, | |
1363 | .bdrv_open = qcow_open, | |
1364 | .bdrv_close = qcow_close, | |
1365 | .bdrv_create = qcow_create, | |
1366 | .bdrv_flush = qcow_flush, | |
1367 | .bdrv_is_allocated = qcow_is_allocated, | |
1368 | .bdrv_set_key = qcow_set_key, | |
1369 | .bdrv_make_empty = qcow_make_empty, | |
1370 | ||
1371 | .bdrv_aio_readv = qcow_aio_readv, | |
1372 | .bdrv_aio_writev = qcow_aio_writev, | |
1373 | .bdrv_aio_flush = qcow_aio_flush, | |
419b19d9 SH |
1374 | |
1375 | .bdrv_truncate = qcow2_truncate, | |
1376 | .bdrv_write_compressed = qcow_write_compressed, | |
20d97356 BS |
1377 | |
1378 | .bdrv_snapshot_create = qcow2_snapshot_create, | |
1379 | .bdrv_snapshot_goto = qcow2_snapshot_goto, | |
1380 | .bdrv_snapshot_delete = qcow2_snapshot_delete, | |
1381 | .bdrv_snapshot_list = qcow2_snapshot_list, | |
1382 | .bdrv_get_info = qcow_get_info, | |
1383 | ||
1384 | .bdrv_save_vmstate = qcow_save_vmstate, | |
1385 | .bdrv_load_vmstate = qcow_load_vmstate, | |
1386 | ||
1387 | .bdrv_change_backing_file = qcow2_change_backing_file, | |
1388 | ||
1389 | .create_options = qcow_create_options, | |
1390 | .bdrv_check = qcow_check, | |
1391 | }; | |
1392 | ||
5efa9d5a AL |
1393 | static void bdrv_qcow2_init(void) |
1394 | { | |
1395 | bdrv_register(&bdrv_qcow2); | |
1396 | } | |
1397 | ||
1398 | block_init(bdrv_qcow2_init); |