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1 | /* | |
2 | * Block driver for the QCOW version 2 format | |
3 | * | |
4 | * Copyright (c) 2004-2006 Fabrice Bellard | |
5 | * | |
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 | */ | |
24 | #include "qemu-common.h" | |
25 | #include "block/block_int.h" | |
26 | #include "qemu/module.h" | |
27 | #include <zlib.h> | |
28 | #include "qemu/aes.h" | |
29 | #include "block/qcow2.h" | |
30 | #include "qemu/error-report.h" | |
31 | #include "qapi/qmp/qerror.h" | |
32 | #include "qapi/qmp/qbool.h" | |
33 | #include "trace.h" | |
34 | ||
35 | /* | |
36 | Differences with QCOW: | |
37 | ||
38 | - Support for multiple incremental snapshots. | |
39 | - Memory management by reference counts. | |
40 | - Clusters which have a reference count of one have the bit | |
41 | QCOW_OFLAG_COPIED to optimize write performance. | |
42 | - Size of compressed clusters is stored in sectors to reduce bit usage | |
43 | in the cluster offsets. | |
44 | - Support for storing additional data (such as the VM state) in the | |
45 | snapshots. | |
46 | - If a backing store is used, the cluster size is not constrained | |
47 | (could be backported to QCOW). | |
48 | - L2 tables have always a size of one cluster. | |
49 | */ | |
50 | ||
51 | ||
52 | typedef struct { | |
53 | uint32_t magic; | |
54 | uint32_t len; | |
55 | } QEMU_PACKED QCowExtension; | |
56 | ||
57 | #define QCOW2_EXT_MAGIC_END 0 | |
58 | #define QCOW2_EXT_MAGIC_BACKING_FORMAT 0xE2792ACA | |
59 | #define QCOW2_EXT_MAGIC_FEATURE_TABLE 0x6803f857 | |
60 | ||
61 | static int qcow2_probe(const uint8_t *buf, int buf_size, const char *filename) | |
62 | { | |
63 | const QCowHeader *cow_header = (const void *)buf; | |
64 | ||
65 | if (buf_size >= sizeof(QCowHeader) && | |
66 | be32_to_cpu(cow_header->magic) == QCOW_MAGIC && | |
67 | be32_to_cpu(cow_header->version) >= 2) | |
68 | return 100; | |
69 | else | |
70 | return 0; | |
71 | } | |
72 | ||
73 | ||
74 | /* | |
75 | * read qcow2 extension and fill bs | |
76 | * start reading from start_offset | |
77 | * finish reading upon magic of value 0 or when end_offset reached | |
78 | * unknown magic is skipped (future extension this version knows nothing about) | |
79 | * return 0 upon success, non-0 otherwise | |
80 | */ | |
81 | static int qcow2_read_extensions(BlockDriverState *bs, uint64_t start_offset, | |
82 | uint64_t end_offset, void **p_feature_table, | |
83 | Error **errp) | |
84 | { | |
85 | BDRVQcowState *s = bs->opaque; | |
86 | QCowExtension ext; | |
87 | uint64_t offset; | |
88 | int ret; | |
89 | ||
90 | #ifdef DEBUG_EXT | |
91 | printf("qcow2_read_extensions: start=%ld end=%ld\n", start_offset, end_offset); | |
92 | #endif | |
93 | offset = start_offset; | |
94 | while (offset < end_offset) { | |
95 | ||
96 | #ifdef DEBUG_EXT | |
97 | /* Sanity check */ | |
98 | if (offset > s->cluster_size) | |
99 | printf("qcow2_read_extension: suspicious offset %lu\n", offset); | |
100 | ||
101 | printf("attempting to read extended header in offset %lu\n", offset); | |
102 | #endif | |
103 | ||
104 | ret = bdrv_pread(bs->file, offset, &ext, sizeof(ext)); | |
105 | if (ret < 0) { | |
106 | error_setg_errno(errp, -ret, "qcow2_read_extension: ERROR: " | |
107 | "pread fail from offset %" PRIu64, offset); | |
108 | return 1; | |
109 | } | |
110 | be32_to_cpus(&ext.magic); | |
111 | be32_to_cpus(&ext.len); | |
112 | offset += sizeof(ext); | |
113 | #ifdef DEBUG_EXT | |
114 | printf("ext.magic = 0x%x\n", ext.magic); | |
115 | #endif | |
116 | if (ext.len > end_offset - offset) { | |
117 | error_setg(errp, "Header extension too large"); | |
118 | return -EINVAL; | |
119 | } | |
120 | ||
121 | switch (ext.magic) { | |
122 | case QCOW2_EXT_MAGIC_END: | |
123 | return 0; | |
124 | ||
125 | case QCOW2_EXT_MAGIC_BACKING_FORMAT: | |
126 | if (ext.len >= sizeof(bs->backing_format)) { | |
127 | error_setg(errp, "ERROR: ext_backing_format: len=%u too large" | |
128 | " (>=%zu)", ext.len, sizeof(bs->backing_format)); | |
129 | return 2; | |
130 | } | |
131 | ret = bdrv_pread(bs->file, offset, bs->backing_format, ext.len); | |
132 | if (ret < 0) { | |
133 | error_setg_errno(errp, -ret, "ERROR: ext_backing_format: " | |
134 | "Could not read format name"); | |
135 | return 3; | |
136 | } | |
137 | bs->backing_format[ext.len] = '\0'; | |
138 | #ifdef DEBUG_EXT | |
139 | printf("Qcow2: Got format extension %s\n", bs->backing_format); | |
140 | #endif | |
141 | break; | |
142 | ||
143 | case QCOW2_EXT_MAGIC_FEATURE_TABLE: | |
144 | if (p_feature_table != NULL) { | |
145 | void* feature_table = g_malloc0(ext.len + 2 * sizeof(Qcow2Feature)); | |
146 | ret = bdrv_pread(bs->file, offset , feature_table, ext.len); | |
147 | if (ret < 0) { | |
148 | error_setg_errno(errp, -ret, "ERROR: ext_feature_table: " | |
149 | "Could not read table"); | |
150 | return ret; | |
151 | } | |
152 | ||
153 | *p_feature_table = feature_table; | |
154 | } | |
155 | break; | |
156 | ||
157 | default: | |
158 | /* unknown magic - save it in case we need to rewrite the header */ | |
159 | { | |
160 | Qcow2UnknownHeaderExtension *uext; | |
161 | ||
162 | uext = g_malloc0(sizeof(*uext) + ext.len); | |
163 | uext->magic = ext.magic; | |
164 | uext->len = ext.len; | |
165 | QLIST_INSERT_HEAD(&s->unknown_header_ext, uext, next); | |
166 | ||
167 | ret = bdrv_pread(bs->file, offset , uext->data, uext->len); | |
168 | if (ret < 0) { | |
169 | error_setg_errno(errp, -ret, "ERROR: unknown extension: " | |
170 | "Could not read data"); | |
171 | return ret; | |
172 | } | |
173 | } | |
174 | break; | |
175 | } | |
176 | ||
177 | offset += ((ext.len + 7) & ~7); | |
178 | } | |
179 | ||
180 | return 0; | |
181 | } | |
182 | ||
183 | static void cleanup_unknown_header_ext(BlockDriverState *bs) | |
184 | { | |
185 | BDRVQcowState *s = bs->opaque; | |
186 | Qcow2UnknownHeaderExtension *uext, *next; | |
187 | ||
188 | QLIST_FOREACH_SAFE(uext, &s->unknown_header_ext, next, next) { | |
189 | QLIST_REMOVE(uext, next); | |
190 | g_free(uext); | |
191 | } | |
192 | } | |
193 | ||
194 | static void GCC_FMT_ATTR(3, 4) report_unsupported(BlockDriverState *bs, | |
195 | Error **errp, const char *fmt, ...) | |
196 | { | |
197 | char msg[64]; | |
198 | va_list ap; | |
199 | ||
200 | va_start(ap, fmt); | |
201 | vsnprintf(msg, sizeof(msg), fmt, ap); | |
202 | va_end(ap); | |
203 | ||
204 | error_set(errp, QERR_UNKNOWN_BLOCK_FORMAT_FEATURE, bs->device_name, "qcow2", | |
205 | msg); | |
206 | } | |
207 | ||
208 | static void report_unsupported_feature(BlockDriverState *bs, | |
209 | Error **errp, Qcow2Feature *table, uint64_t mask) | |
210 | { | |
211 | while (table && table->name[0] != '\0') { | |
212 | if (table->type == QCOW2_FEAT_TYPE_INCOMPATIBLE) { | |
213 | if (mask & (1 << table->bit)) { | |
214 | report_unsupported(bs, errp, "%.46s", table->name); | |
215 | mask &= ~(1 << table->bit); | |
216 | } | |
217 | } | |
218 | table++; | |
219 | } | |
220 | ||
221 | if (mask) { | |
222 | report_unsupported(bs, errp, "Unknown incompatible feature: %" PRIx64, | |
223 | mask); | |
224 | } | |
225 | } | |
226 | ||
227 | /* | |
228 | * Sets the dirty bit and flushes afterwards if necessary. | |
229 | * | |
230 | * The incompatible_features bit is only set if the image file header was | |
231 | * updated successfully. Therefore it is not required to check the return | |
232 | * value of this function. | |
233 | */ | |
234 | int qcow2_mark_dirty(BlockDriverState *bs) | |
235 | { | |
236 | BDRVQcowState *s = bs->opaque; | |
237 | uint64_t val; | |
238 | int ret; | |
239 | ||
240 | assert(s->qcow_version >= 3); | |
241 | ||
242 | if (s->incompatible_features & QCOW2_INCOMPAT_DIRTY) { | |
243 | return 0; /* already dirty */ | |
244 | } | |
245 | ||
246 | val = cpu_to_be64(s->incompatible_features | QCOW2_INCOMPAT_DIRTY); | |
247 | ret = bdrv_pwrite(bs->file, offsetof(QCowHeader, incompatible_features), | |
248 | &val, sizeof(val)); | |
249 | if (ret < 0) { | |
250 | return ret; | |
251 | } | |
252 | ret = bdrv_flush(bs->file); | |
253 | if (ret < 0) { | |
254 | return ret; | |
255 | } | |
256 | ||
257 | /* Only treat image as dirty if the header was updated successfully */ | |
258 | s->incompatible_features |= QCOW2_INCOMPAT_DIRTY; | |
259 | return 0; | |
260 | } | |
261 | ||
262 | /* | |
263 | * Clears the dirty bit and flushes before if necessary. Only call this | |
264 | * function when there are no pending requests, it does not guard against | |
265 | * concurrent requests dirtying the image. | |
266 | */ | |
267 | static int qcow2_mark_clean(BlockDriverState *bs) | |
268 | { | |
269 | BDRVQcowState *s = bs->opaque; | |
270 | ||
271 | if (s->incompatible_features & QCOW2_INCOMPAT_DIRTY) { | |
272 | int ret = bdrv_flush(bs); | |
273 | if (ret < 0) { | |
274 | return ret; | |
275 | } | |
276 | ||
277 | s->incompatible_features &= ~QCOW2_INCOMPAT_DIRTY; | |
278 | return qcow2_update_header(bs); | |
279 | } | |
280 | return 0; | |
281 | } | |
282 | ||
283 | /* | |
284 | * Marks the image as corrupt. | |
285 | */ | |
286 | int qcow2_mark_corrupt(BlockDriverState *bs) | |
287 | { | |
288 | BDRVQcowState *s = bs->opaque; | |
289 | ||
290 | s->incompatible_features |= QCOW2_INCOMPAT_CORRUPT; | |
291 | return qcow2_update_header(bs); | |
292 | } | |
293 | ||
294 | /* | |
295 | * Marks the image as consistent, i.e., unsets the corrupt bit, and flushes | |
296 | * before if necessary. | |
297 | */ | |
298 | int qcow2_mark_consistent(BlockDriverState *bs) | |
299 | { | |
300 | BDRVQcowState *s = bs->opaque; | |
301 | ||
302 | if (s->incompatible_features & QCOW2_INCOMPAT_CORRUPT) { | |
303 | int ret = bdrv_flush(bs); | |
304 | if (ret < 0) { | |
305 | return ret; | |
306 | } | |
307 | ||
308 | s->incompatible_features &= ~QCOW2_INCOMPAT_CORRUPT; | |
309 | return qcow2_update_header(bs); | |
310 | } | |
311 | return 0; | |
312 | } | |
313 | ||
314 | static int qcow2_check(BlockDriverState *bs, BdrvCheckResult *result, | |
315 | BdrvCheckMode fix) | |
316 | { | |
317 | int ret = qcow2_check_refcounts(bs, result, fix); | |
318 | if (ret < 0) { | |
319 | return ret; | |
320 | } | |
321 | ||
322 | if (fix && result->check_errors == 0 && result->corruptions == 0) { | |
323 | ret = qcow2_mark_clean(bs); | |
324 | if (ret < 0) { | |
325 | return ret; | |
326 | } | |
327 | return qcow2_mark_consistent(bs); | |
328 | } | |
329 | return ret; | |
330 | } | |
331 | ||
332 | static QemuOptsList qcow2_runtime_opts = { | |
333 | .name = "qcow2", | |
334 | .head = QTAILQ_HEAD_INITIALIZER(qcow2_runtime_opts.head), | |
335 | .desc = { | |
336 | { | |
337 | .name = QCOW2_OPT_LAZY_REFCOUNTS, | |
338 | .type = QEMU_OPT_BOOL, | |
339 | .help = "Postpone refcount updates", | |
340 | }, | |
341 | { | |
342 | .name = QCOW2_OPT_DISCARD_REQUEST, | |
343 | .type = QEMU_OPT_BOOL, | |
344 | .help = "Pass guest discard requests to the layer below", | |
345 | }, | |
346 | { | |
347 | .name = QCOW2_OPT_DISCARD_SNAPSHOT, | |
348 | .type = QEMU_OPT_BOOL, | |
349 | .help = "Generate discard requests when snapshot related space " | |
350 | "is freed", | |
351 | }, | |
352 | { | |
353 | .name = QCOW2_OPT_DISCARD_OTHER, | |
354 | .type = QEMU_OPT_BOOL, | |
355 | .help = "Generate discard requests when other clusters are freed", | |
356 | }, | |
357 | { | |
358 | .name = QCOW2_OPT_OVERLAP, | |
359 | .type = QEMU_OPT_STRING, | |
360 | .help = "Selects which overlap checks to perform from a range of " | |
361 | "templates (none, constant, cached, all)", | |
362 | }, | |
363 | { | |
364 | .name = QCOW2_OPT_OVERLAP_MAIN_HEADER, | |
365 | .type = QEMU_OPT_BOOL, | |
366 | .help = "Check for unintended writes into the main qcow2 header", | |
367 | }, | |
368 | { | |
369 | .name = QCOW2_OPT_OVERLAP_ACTIVE_L1, | |
370 | .type = QEMU_OPT_BOOL, | |
371 | .help = "Check for unintended writes into the active L1 table", | |
372 | }, | |
373 | { | |
374 | .name = QCOW2_OPT_OVERLAP_ACTIVE_L2, | |
375 | .type = QEMU_OPT_BOOL, | |
376 | .help = "Check for unintended writes into an active L2 table", | |
377 | }, | |
378 | { | |
379 | .name = QCOW2_OPT_OVERLAP_REFCOUNT_TABLE, | |
380 | .type = QEMU_OPT_BOOL, | |
381 | .help = "Check for unintended writes into the refcount table", | |
382 | }, | |
383 | { | |
384 | .name = QCOW2_OPT_OVERLAP_REFCOUNT_BLOCK, | |
385 | .type = QEMU_OPT_BOOL, | |
386 | .help = "Check for unintended writes into a refcount block", | |
387 | }, | |
388 | { | |
389 | .name = QCOW2_OPT_OVERLAP_SNAPSHOT_TABLE, | |
390 | .type = QEMU_OPT_BOOL, | |
391 | .help = "Check for unintended writes into the snapshot table", | |
392 | }, | |
393 | { | |
394 | .name = QCOW2_OPT_OVERLAP_INACTIVE_L1, | |
395 | .type = QEMU_OPT_BOOL, | |
396 | .help = "Check for unintended writes into an inactive L1 table", | |
397 | }, | |
398 | { | |
399 | .name = QCOW2_OPT_OVERLAP_INACTIVE_L2, | |
400 | .type = QEMU_OPT_BOOL, | |
401 | .help = "Check for unintended writes into an inactive L2 table", | |
402 | }, | |
403 | { /* end of list */ } | |
404 | }, | |
405 | }; | |
406 | ||
407 | static const char *overlap_bool_option_names[QCOW2_OL_MAX_BITNR] = { | |
408 | [QCOW2_OL_MAIN_HEADER_BITNR] = QCOW2_OPT_OVERLAP_MAIN_HEADER, | |
409 | [QCOW2_OL_ACTIVE_L1_BITNR] = QCOW2_OPT_OVERLAP_ACTIVE_L1, | |
410 | [QCOW2_OL_ACTIVE_L2_BITNR] = QCOW2_OPT_OVERLAP_ACTIVE_L2, | |
411 | [QCOW2_OL_REFCOUNT_TABLE_BITNR] = QCOW2_OPT_OVERLAP_REFCOUNT_TABLE, | |
412 | [QCOW2_OL_REFCOUNT_BLOCK_BITNR] = QCOW2_OPT_OVERLAP_REFCOUNT_BLOCK, | |
413 | [QCOW2_OL_SNAPSHOT_TABLE_BITNR] = QCOW2_OPT_OVERLAP_SNAPSHOT_TABLE, | |
414 | [QCOW2_OL_INACTIVE_L1_BITNR] = QCOW2_OPT_OVERLAP_INACTIVE_L1, | |
415 | [QCOW2_OL_INACTIVE_L2_BITNR] = QCOW2_OPT_OVERLAP_INACTIVE_L2, | |
416 | }; | |
417 | ||
418 | static int qcow2_open(BlockDriverState *bs, QDict *options, int flags, | |
419 | Error **errp) | |
420 | { | |
421 | BDRVQcowState *s = bs->opaque; | |
422 | int len, i, ret = 0; | |
423 | QCowHeader header; | |
424 | QemuOpts *opts; | |
425 | Error *local_err = NULL; | |
426 | uint64_t ext_end; | |
427 | uint64_t l1_vm_state_index; | |
428 | const char *opt_overlap_check; | |
429 | int overlap_check_template = 0; | |
430 | ||
431 | ret = bdrv_pread(bs->file, 0, &header, sizeof(header)); | |
432 | if (ret < 0) { | |
433 | error_setg_errno(errp, -ret, "Could not read qcow2 header"); | |
434 | goto fail; | |
435 | } | |
436 | be32_to_cpus(&header.magic); | |
437 | be32_to_cpus(&header.version); | |
438 | be64_to_cpus(&header.backing_file_offset); | |
439 | be32_to_cpus(&header.backing_file_size); | |
440 | be64_to_cpus(&header.size); | |
441 | be32_to_cpus(&header.cluster_bits); | |
442 | be32_to_cpus(&header.crypt_method); | |
443 | be64_to_cpus(&header.l1_table_offset); | |
444 | be32_to_cpus(&header.l1_size); | |
445 | be64_to_cpus(&header.refcount_table_offset); | |
446 | be32_to_cpus(&header.refcount_table_clusters); | |
447 | be64_to_cpus(&header.snapshots_offset); | |
448 | be32_to_cpus(&header.nb_snapshots); | |
449 | ||
450 | if (header.magic != QCOW_MAGIC) { | |
451 | error_setg(errp, "Image is not in qcow2 format"); | |
452 | ret = -EMEDIUMTYPE; | |
453 | goto fail; | |
454 | } | |
455 | if (header.version < 2 || header.version > 3) { | |
456 | report_unsupported(bs, errp, "QCOW version %d", header.version); | |
457 | ret = -ENOTSUP; | |
458 | goto fail; | |
459 | } | |
460 | ||
461 | s->qcow_version = header.version; | |
462 | ||
463 | /* Initialise version 3 header fields */ | |
464 | if (header.version == 2) { | |
465 | header.incompatible_features = 0; | |
466 | header.compatible_features = 0; | |
467 | header.autoclear_features = 0; | |
468 | header.refcount_order = 4; | |
469 | header.header_length = 72; | |
470 | } else { | |
471 | be64_to_cpus(&header.incompatible_features); | |
472 | be64_to_cpus(&header.compatible_features); | |
473 | be64_to_cpus(&header.autoclear_features); | |
474 | be32_to_cpus(&header.refcount_order); | |
475 | be32_to_cpus(&header.header_length); | |
476 | } | |
477 | ||
478 | if (header.header_length > sizeof(header)) { | |
479 | s->unknown_header_fields_size = header.header_length - sizeof(header); | |
480 | s->unknown_header_fields = g_malloc(s->unknown_header_fields_size); | |
481 | ret = bdrv_pread(bs->file, sizeof(header), s->unknown_header_fields, | |
482 | s->unknown_header_fields_size); | |
483 | if (ret < 0) { | |
484 | error_setg_errno(errp, -ret, "Could not read unknown qcow2 header " | |
485 | "fields"); | |
486 | goto fail; | |
487 | } | |
488 | } | |
489 | ||
490 | if (header.backing_file_offset) { | |
491 | ext_end = header.backing_file_offset; | |
492 | } else { | |
493 | ext_end = 1 << header.cluster_bits; | |
494 | } | |
495 | ||
496 | /* Handle feature bits */ | |
497 | s->incompatible_features = header.incompatible_features; | |
498 | s->compatible_features = header.compatible_features; | |
499 | s->autoclear_features = header.autoclear_features; | |
500 | ||
501 | if (s->incompatible_features & ~QCOW2_INCOMPAT_MASK) { | |
502 | void *feature_table = NULL; | |
503 | qcow2_read_extensions(bs, header.header_length, ext_end, | |
504 | &feature_table, NULL); | |
505 | report_unsupported_feature(bs, errp, feature_table, | |
506 | s->incompatible_features & | |
507 | ~QCOW2_INCOMPAT_MASK); | |
508 | ret = -ENOTSUP; | |
509 | goto fail; | |
510 | } | |
511 | ||
512 | if (s->incompatible_features & QCOW2_INCOMPAT_CORRUPT) { | |
513 | /* Corrupt images may not be written to unless they are being repaired | |
514 | */ | |
515 | if ((flags & BDRV_O_RDWR) && !(flags & BDRV_O_CHECK)) { | |
516 | error_setg(errp, "qcow2: Image is corrupt; cannot be opened " | |
517 | "read/write"); | |
518 | ret = -EACCES; | |
519 | goto fail; | |
520 | } | |
521 | } | |
522 | ||
523 | /* Check support for various header values */ | |
524 | if (header.refcount_order != 4) { | |
525 | report_unsupported(bs, errp, "%d bit reference counts", | |
526 | 1 << header.refcount_order); | |
527 | ret = -ENOTSUP; | |
528 | goto fail; | |
529 | } | |
530 | s->refcount_order = header.refcount_order; | |
531 | ||
532 | if (header.cluster_bits < MIN_CLUSTER_BITS || | |
533 | header.cluster_bits > MAX_CLUSTER_BITS) { | |
534 | error_setg(errp, "Unsupported cluster size: 2^%i", header.cluster_bits); | |
535 | ret = -EINVAL; | |
536 | goto fail; | |
537 | } | |
538 | if (header.crypt_method > QCOW_CRYPT_AES) { | |
539 | error_setg(errp, "Unsupported encryption method: %i", | |
540 | header.crypt_method); | |
541 | ret = -EINVAL; | |
542 | goto fail; | |
543 | } | |
544 | s->crypt_method_header = header.crypt_method; | |
545 | if (s->crypt_method_header) { | |
546 | bs->encrypted = 1; | |
547 | } | |
548 | s->cluster_bits = header.cluster_bits; | |
549 | s->cluster_size = 1 << s->cluster_bits; | |
550 | s->cluster_sectors = 1 << (s->cluster_bits - 9); | |
551 | s->l2_bits = s->cluster_bits - 3; /* L2 is always one cluster */ | |
552 | s->l2_size = 1 << s->l2_bits; | |
553 | bs->total_sectors = header.size / 512; | |
554 | s->csize_shift = (62 - (s->cluster_bits - 8)); | |
555 | s->csize_mask = (1 << (s->cluster_bits - 8)) - 1; | |
556 | s->cluster_offset_mask = (1LL << s->csize_shift) - 1; | |
557 | s->refcount_table_offset = header.refcount_table_offset; | |
558 | s->refcount_table_size = | |
559 | header.refcount_table_clusters << (s->cluster_bits - 3); | |
560 | ||
561 | s->snapshots_offset = header.snapshots_offset; | |
562 | s->nb_snapshots = header.nb_snapshots; | |
563 | ||
564 | /* read the level 1 table */ | |
565 | s->l1_size = header.l1_size; | |
566 | ||
567 | l1_vm_state_index = size_to_l1(s, header.size); | |
568 | if (l1_vm_state_index > INT_MAX) { | |
569 | error_setg(errp, "Image is too big"); | |
570 | ret = -EFBIG; | |
571 | goto fail; | |
572 | } | |
573 | s->l1_vm_state_index = l1_vm_state_index; | |
574 | ||
575 | /* the L1 table must contain at least enough entries to put | |
576 | header.size bytes */ | |
577 | if (s->l1_size < s->l1_vm_state_index) { | |
578 | error_setg(errp, "L1 table is too small"); | |
579 | ret = -EINVAL; | |
580 | goto fail; | |
581 | } | |
582 | s->l1_table_offset = header.l1_table_offset; | |
583 | if (s->l1_size > 0) { | |
584 | s->l1_table = g_malloc0( | |
585 | align_offset(s->l1_size * sizeof(uint64_t), 512)); | |
586 | ret = bdrv_pread(bs->file, s->l1_table_offset, s->l1_table, | |
587 | s->l1_size * sizeof(uint64_t)); | |
588 | if (ret < 0) { | |
589 | error_setg_errno(errp, -ret, "Could not read L1 table"); | |
590 | goto fail; | |
591 | } | |
592 | for(i = 0;i < s->l1_size; i++) { | |
593 | be64_to_cpus(&s->l1_table[i]); | |
594 | } | |
595 | } | |
596 | ||
597 | /* alloc L2 table/refcount block cache */ | |
598 | s->l2_table_cache = qcow2_cache_create(bs, L2_CACHE_SIZE); | |
599 | s->refcount_block_cache = qcow2_cache_create(bs, REFCOUNT_CACHE_SIZE); | |
600 | ||
601 | s->cluster_cache = g_malloc(s->cluster_size); | |
602 | /* one more sector for decompressed data alignment */ | |
603 | s->cluster_data = qemu_blockalign(bs, QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size | |
604 | + 512); | |
605 | s->cluster_cache_offset = -1; | |
606 | s->flags = flags; | |
607 | ||
608 | ret = qcow2_refcount_init(bs); | |
609 | if (ret != 0) { | |
610 | error_setg_errno(errp, -ret, "Could not initialize refcount handling"); | |
611 | goto fail; | |
612 | } | |
613 | ||
614 | QLIST_INIT(&s->cluster_allocs); | |
615 | QTAILQ_INIT(&s->discards); | |
616 | ||
617 | /* read qcow2 extensions */ | |
618 | if (qcow2_read_extensions(bs, header.header_length, ext_end, NULL, | |
619 | &local_err)) { | |
620 | error_propagate(errp, local_err); | |
621 | ret = -EINVAL; | |
622 | goto fail; | |
623 | } | |
624 | ||
625 | /* read the backing file name */ | |
626 | if (header.backing_file_offset != 0) { | |
627 | len = header.backing_file_size; | |
628 | if (len > 1023) { | |
629 | len = 1023; | |
630 | } | |
631 | ret = bdrv_pread(bs->file, header.backing_file_offset, | |
632 | bs->backing_file, len); | |
633 | if (ret < 0) { | |
634 | error_setg_errno(errp, -ret, "Could not read backing file name"); | |
635 | goto fail; | |
636 | } | |
637 | bs->backing_file[len] = '\0'; | |
638 | } | |
639 | ||
640 | ret = qcow2_read_snapshots(bs); | |
641 | if (ret < 0) { | |
642 | error_setg_errno(errp, -ret, "Could not read snapshots"); | |
643 | goto fail; | |
644 | } | |
645 | ||
646 | /* Clear unknown autoclear feature bits */ | |
647 | if (!bs->read_only && s->autoclear_features != 0) { | |
648 | s->autoclear_features = 0; | |
649 | ret = qcow2_update_header(bs); | |
650 | if (ret < 0) { | |
651 | error_setg_errno(errp, -ret, "Could not update qcow2 header"); | |
652 | goto fail; | |
653 | } | |
654 | } | |
655 | ||
656 | /* Initialise locks */ | |
657 | qemu_co_mutex_init(&s->lock); | |
658 | ||
659 | /* Repair image if dirty */ | |
660 | if (!(flags & BDRV_O_CHECK) && !bs->read_only && | |
661 | (s->incompatible_features & QCOW2_INCOMPAT_DIRTY)) { | |
662 | BdrvCheckResult result = {0}; | |
663 | ||
664 | ret = qcow2_check(bs, &result, BDRV_FIX_ERRORS); | |
665 | if (ret < 0) { | |
666 | error_setg_errno(errp, -ret, "Could not repair dirty image"); | |
667 | goto fail; | |
668 | } | |
669 | } | |
670 | ||
671 | /* Enable lazy_refcounts according to image and command line options */ | |
672 | opts = qemu_opts_create_nofail(&qcow2_runtime_opts); | |
673 | qemu_opts_absorb_qdict(opts, options, &local_err); | |
674 | if (error_is_set(&local_err)) { | |
675 | error_propagate(errp, local_err); | |
676 | ret = -EINVAL; | |
677 | goto fail; | |
678 | } | |
679 | ||
680 | s->use_lazy_refcounts = qemu_opt_get_bool(opts, QCOW2_OPT_LAZY_REFCOUNTS, | |
681 | (s->compatible_features & QCOW2_COMPAT_LAZY_REFCOUNTS)); | |
682 | ||
683 | s->discard_passthrough[QCOW2_DISCARD_NEVER] = false; | |
684 | s->discard_passthrough[QCOW2_DISCARD_ALWAYS] = true; | |
685 | s->discard_passthrough[QCOW2_DISCARD_REQUEST] = | |
686 | qemu_opt_get_bool(opts, QCOW2_OPT_DISCARD_REQUEST, | |
687 | flags & BDRV_O_UNMAP); | |
688 | s->discard_passthrough[QCOW2_DISCARD_SNAPSHOT] = | |
689 | qemu_opt_get_bool(opts, QCOW2_OPT_DISCARD_SNAPSHOT, true); | |
690 | s->discard_passthrough[QCOW2_DISCARD_OTHER] = | |
691 | qemu_opt_get_bool(opts, QCOW2_OPT_DISCARD_OTHER, false); | |
692 | ||
693 | opt_overlap_check = qemu_opt_get(opts, "overlap-check") ?: "cached"; | |
694 | if (!strcmp(opt_overlap_check, "none")) { | |
695 | overlap_check_template = 0; | |
696 | } else if (!strcmp(opt_overlap_check, "constant")) { | |
697 | overlap_check_template = QCOW2_OL_CONSTANT; | |
698 | } else if (!strcmp(opt_overlap_check, "cached")) { | |
699 | overlap_check_template = QCOW2_OL_CACHED; | |
700 | } else if (!strcmp(opt_overlap_check, "all")) { | |
701 | overlap_check_template = QCOW2_OL_ALL; | |
702 | } else { | |
703 | error_setg(errp, "Unsupported value '%s' for qcow2 option " | |
704 | "'overlap-check'. Allowed are either of the following: " | |
705 | "none, constant, cached, all", opt_overlap_check); | |
706 | qemu_opts_del(opts); | |
707 | ret = -EINVAL; | |
708 | goto fail; | |
709 | } | |
710 | ||
711 | s->overlap_check = 0; | |
712 | for (i = 0; i < QCOW2_OL_MAX_BITNR; i++) { | |
713 | /* overlap-check defines a template bitmask, but every flag may be | |
714 | * overwritten through the associated boolean option */ | |
715 | s->overlap_check |= | |
716 | qemu_opt_get_bool(opts, overlap_bool_option_names[i], | |
717 | overlap_check_template & (1 << i)) << i; | |
718 | } | |
719 | ||
720 | qemu_opts_del(opts); | |
721 | ||
722 | if (s->use_lazy_refcounts && s->qcow_version < 3) { | |
723 | error_setg(errp, "Lazy refcounts require a qcow2 image with at least " | |
724 | "qemu 1.1 compatibility level"); | |
725 | ret = -EINVAL; | |
726 | goto fail; | |
727 | } | |
728 | ||
729 | #ifdef DEBUG_ALLOC | |
730 | { | |
731 | BdrvCheckResult result = {0}; | |
732 | qcow2_check_refcounts(bs, &result, 0); | |
733 | } | |
734 | #endif | |
735 | return ret; | |
736 | ||
737 | fail: | |
738 | g_free(s->unknown_header_fields); | |
739 | cleanup_unknown_header_ext(bs); | |
740 | qcow2_free_snapshots(bs); | |
741 | qcow2_refcount_close(bs); | |
742 | g_free(s->l1_table); | |
743 | /* else pre-write overlap checks in cache_destroy may crash */ | |
744 | s->l1_table = NULL; | |
745 | if (s->l2_table_cache) { | |
746 | qcow2_cache_destroy(bs, s->l2_table_cache); | |
747 | } | |
748 | g_free(s->cluster_cache); | |
749 | qemu_vfree(s->cluster_data); | |
750 | return ret; | |
751 | } | |
752 | ||
753 | static int qcow2_set_key(BlockDriverState *bs, const char *key) | |
754 | { | |
755 | BDRVQcowState *s = bs->opaque; | |
756 | uint8_t keybuf[16]; | |
757 | int len, i; | |
758 | ||
759 | memset(keybuf, 0, 16); | |
760 | len = strlen(key); | |
761 | if (len > 16) | |
762 | len = 16; | |
763 | /* XXX: we could compress the chars to 7 bits to increase | |
764 | entropy */ | |
765 | for(i = 0;i < len;i++) { | |
766 | keybuf[i] = key[i]; | |
767 | } | |
768 | s->crypt_method = s->crypt_method_header; | |
769 | ||
770 | if (AES_set_encrypt_key(keybuf, 128, &s->aes_encrypt_key) != 0) | |
771 | return -1; | |
772 | if (AES_set_decrypt_key(keybuf, 128, &s->aes_decrypt_key) != 0) | |
773 | return -1; | |
774 | #if 0 | |
775 | /* test */ | |
776 | { | |
777 | uint8_t in[16]; | |
778 | uint8_t out[16]; | |
779 | uint8_t tmp[16]; | |
780 | for(i=0;i<16;i++) | |
781 | in[i] = i; | |
782 | AES_encrypt(in, tmp, &s->aes_encrypt_key); | |
783 | AES_decrypt(tmp, out, &s->aes_decrypt_key); | |
784 | for(i = 0; i < 16; i++) | |
785 | printf(" %02x", tmp[i]); | |
786 | printf("\n"); | |
787 | for(i = 0; i < 16; i++) | |
788 | printf(" %02x", out[i]); | |
789 | printf("\n"); | |
790 | } | |
791 | #endif | |
792 | return 0; | |
793 | } | |
794 | ||
795 | /* We have nothing to do for QCOW2 reopen, stubs just return | |
796 | * success */ | |
797 | static int qcow2_reopen_prepare(BDRVReopenState *state, | |
798 | BlockReopenQueue *queue, Error **errp) | |
799 | { | |
800 | return 0; | |
801 | } | |
802 | ||
803 | static int64_t coroutine_fn qcow2_co_get_block_status(BlockDriverState *bs, | |
804 | int64_t sector_num, int nb_sectors, int *pnum) | |
805 | { | |
806 | BDRVQcowState *s = bs->opaque; | |
807 | uint64_t cluster_offset; | |
808 | int index_in_cluster, ret; | |
809 | int64_t status = 0; | |
810 | ||
811 | *pnum = nb_sectors; | |
812 | qemu_co_mutex_lock(&s->lock); | |
813 | ret = qcow2_get_cluster_offset(bs, sector_num << 9, pnum, &cluster_offset); | |
814 | qemu_co_mutex_unlock(&s->lock); | |
815 | if (ret < 0) { | |
816 | return ret; | |
817 | } | |
818 | ||
819 | if (cluster_offset != 0 && ret != QCOW2_CLUSTER_COMPRESSED && | |
820 | !s->crypt_method) { | |
821 | index_in_cluster = sector_num & (s->cluster_sectors - 1); | |
822 | cluster_offset |= (index_in_cluster << BDRV_SECTOR_BITS); | |
823 | status |= BDRV_BLOCK_OFFSET_VALID | cluster_offset; | |
824 | } | |
825 | if (ret == QCOW2_CLUSTER_ZERO) { | |
826 | status |= BDRV_BLOCK_ZERO; | |
827 | } else if (ret != QCOW2_CLUSTER_UNALLOCATED) { | |
828 | status |= BDRV_BLOCK_DATA; | |
829 | } | |
830 | return status; | |
831 | } | |
832 | ||
833 | /* handle reading after the end of the backing file */ | |
834 | int qcow2_backing_read1(BlockDriverState *bs, QEMUIOVector *qiov, | |
835 | int64_t sector_num, int nb_sectors) | |
836 | { | |
837 | int n1; | |
838 | if ((sector_num + nb_sectors) <= bs->total_sectors) | |
839 | return nb_sectors; | |
840 | if (sector_num >= bs->total_sectors) | |
841 | n1 = 0; | |
842 | else | |
843 | n1 = bs->total_sectors - sector_num; | |
844 | ||
845 | qemu_iovec_memset(qiov, 512 * n1, 0, 512 * (nb_sectors - n1)); | |
846 | ||
847 | return n1; | |
848 | } | |
849 | ||
850 | static coroutine_fn int qcow2_co_readv(BlockDriverState *bs, int64_t sector_num, | |
851 | int remaining_sectors, QEMUIOVector *qiov) | |
852 | { | |
853 | BDRVQcowState *s = bs->opaque; | |
854 | int index_in_cluster, n1; | |
855 | int ret; | |
856 | int cur_nr_sectors; /* number of sectors in current iteration */ | |
857 | uint64_t cluster_offset = 0; | |
858 | uint64_t bytes_done = 0; | |
859 | QEMUIOVector hd_qiov; | |
860 | uint8_t *cluster_data = NULL; | |
861 | ||
862 | qemu_iovec_init(&hd_qiov, qiov->niov); | |
863 | ||
864 | qemu_co_mutex_lock(&s->lock); | |
865 | ||
866 | while (remaining_sectors != 0) { | |
867 | ||
868 | /* prepare next request */ | |
869 | cur_nr_sectors = remaining_sectors; | |
870 | if (s->crypt_method) { | |
871 | cur_nr_sectors = MIN(cur_nr_sectors, | |
872 | QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors); | |
873 | } | |
874 | ||
875 | ret = qcow2_get_cluster_offset(bs, sector_num << 9, | |
876 | &cur_nr_sectors, &cluster_offset); | |
877 | if (ret < 0) { | |
878 | goto fail; | |
879 | } | |
880 | ||
881 | index_in_cluster = sector_num & (s->cluster_sectors - 1); | |
882 | ||
883 | qemu_iovec_reset(&hd_qiov); | |
884 | qemu_iovec_concat(&hd_qiov, qiov, bytes_done, | |
885 | cur_nr_sectors * 512); | |
886 | ||
887 | switch (ret) { | |
888 | case QCOW2_CLUSTER_UNALLOCATED: | |
889 | ||
890 | if (bs->backing_hd) { | |
891 | /* read from the base image */ | |
892 | n1 = qcow2_backing_read1(bs->backing_hd, &hd_qiov, | |
893 | sector_num, cur_nr_sectors); | |
894 | if (n1 > 0) { | |
895 | BLKDBG_EVENT(bs->file, BLKDBG_READ_BACKING_AIO); | |
896 | qemu_co_mutex_unlock(&s->lock); | |
897 | ret = bdrv_co_readv(bs->backing_hd, sector_num, | |
898 | n1, &hd_qiov); | |
899 | qemu_co_mutex_lock(&s->lock); | |
900 | if (ret < 0) { | |
901 | goto fail; | |
902 | } | |
903 | } | |
904 | } else { | |
905 | /* Note: in this case, no need to wait */ | |
906 | qemu_iovec_memset(&hd_qiov, 0, 0, 512 * cur_nr_sectors); | |
907 | } | |
908 | break; | |
909 | ||
910 | case QCOW2_CLUSTER_ZERO: | |
911 | qemu_iovec_memset(&hd_qiov, 0, 0, 512 * cur_nr_sectors); | |
912 | break; | |
913 | ||
914 | case QCOW2_CLUSTER_COMPRESSED: | |
915 | /* add AIO support for compressed blocks ? */ | |
916 | ret = qcow2_decompress_cluster(bs, cluster_offset); | |
917 | if (ret < 0) { | |
918 | goto fail; | |
919 | } | |
920 | ||
921 | qemu_iovec_from_buf(&hd_qiov, 0, | |
922 | s->cluster_cache + index_in_cluster * 512, | |
923 | 512 * cur_nr_sectors); | |
924 | break; | |
925 | ||
926 | case QCOW2_CLUSTER_NORMAL: | |
927 | if ((cluster_offset & 511) != 0) { | |
928 | ret = -EIO; | |
929 | goto fail; | |
930 | } | |
931 | ||
932 | if (s->crypt_method) { | |
933 | /* | |
934 | * For encrypted images, read everything into a temporary | |
935 | * contiguous buffer on which the AES functions can work. | |
936 | */ | |
937 | if (!cluster_data) { | |
938 | cluster_data = | |
939 | qemu_blockalign(bs, QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size); | |
940 | } | |
941 | ||
942 | assert(cur_nr_sectors <= | |
943 | QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors); | |
944 | qemu_iovec_reset(&hd_qiov); | |
945 | qemu_iovec_add(&hd_qiov, cluster_data, | |
946 | 512 * cur_nr_sectors); | |
947 | } | |
948 | ||
949 | BLKDBG_EVENT(bs->file, BLKDBG_READ_AIO); | |
950 | qemu_co_mutex_unlock(&s->lock); | |
951 | ret = bdrv_co_readv(bs->file, | |
952 | (cluster_offset >> 9) + index_in_cluster, | |
953 | cur_nr_sectors, &hd_qiov); | |
954 | qemu_co_mutex_lock(&s->lock); | |
955 | if (ret < 0) { | |
956 | goto fail; | |
957 | } | |
958 | if (s->crypt_method) { | |
959 | qcow2_encrypt_sectors(s, sector_num, cluster_data, | |
960 | cluster_data, cur_nr_sectors, 0, &s->aes_decrypt_key); | |
961 | qemu_iovec_from_buf(qiov, bytes_done, | |
962 | cluster_data, 512 * cur_nr_sectors); | |
963 | } | |
964 | break; | |
965 | ||
966 | default: | |
967 | g_assert_not_reached(); | |
968 | ret = -EIO; | |
969 | goto fail; | |
970 | } | |
971 | ||
972 | remaining_sectors -= cur_nr_sectors; | |
973 | sector_num += cur_nr_sectors; | |
974 | bytes_done += cur_nr_sectors * 512; | |
975 | } | |
976 | ret = 0; | |
977 | ||
978 | fail: | |
979 | qemu_co_mutex_unlock(&s->lock); | |
980 | ||
981 | qemu_iovec_destroy(&hd_qiov); | |
982 | qemu_vfree(cluster_data); | |
983 | ||
984 | return ret; | |
985 | } | |
986 | ||
987 | static coroutine_fn int qcow2_co_writev(BlockDriverState *bs, | |
988 | int64_t sector_num, | |
989 | int remaining_sectors, | |
990 | QEMUIOVector *qiov) | |
991 | { | |
992 | BDRVQcowState *s = bs->opaque; | |
993 | int index_in_cluster; | |
994 | int n_end; | |
995 | int ret; | |
996 | int cur_nr_sectors; /* number of sectors in current iteration */ | |
997 | uint64_t cluster_offset; | |
998 | QEMUIOVector hd_qiov; | |
999 | uint64_t bytes_done = 0; | |
1000 | uint8_t *cluster_data = NULL; | |
1001 | QCowL2Meta *l2meta = NULL; | |
1002 | ||
1003 | trace_qcow2_writev_start_req(qemu_coroutine_self(), sector_num, | |
1004 | remaining_sectors); | |
1005 | ||
1006 | qemu_iovec_init(&hd_qiov, qiov->niov); | |
1007 | ||
1008 | s->cluster_cache_offset = -1; /* disable compressed cache */ | |
1009 | ||
1010 | qemu_co_mutex_lock(&s->lock); | |
1011 | ||
1012 | while (remaining_sectors != 0) { | |
1013 | ||
1014 | l2meta = NULL; | |
1015 | ||
1016 | trace_qcow2_writev_start_part(qemu_coroutine_self()); | |
1017 | index_in_cluster = sector_num & (s->cluster_sectors - 1); | |
1018 | n_end = index_in_cluster + remaining_sectors; | |
1019 | if (s->crypt_method && | |
1020 | n_end > QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors) { | |
1021 | n_end = QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors; | |
1022 | } | |
1023 | ||
1024 | ret = qcow2_alloc_cluster_offset(bs, sector_num << 9, | |
1025 | index_in_cluster, n_end, &cur_nr_sectors, &cluster_offset, &l2meta); | |
1026 | if (ret < 0) { | |
1027 | goto fail; | |
1028 | } | |
1029 | ||
1030 | assert((cluster_offset & 511) == 0); | |
1031 | ||
1032 | qemu_iovec_reset(&hd_qiov); | |
1033 | qemu_iovec_concat(&hd_qiov, qiov, bytes_done, | |
1034 | cur_nr_sectors * 512); | |
1035 | ||
1036 | if (s->crypt_method) { | |
1037 | if (!cluster_data) { | |
1038 | cluster_data = qemu_blockalign(bs, QCOW_MAX_CRYPT_CLUSTERS * | |
1039 | s->cluster_size); | |
1040 | } | |
1041 | ||
1042 | assert(hd_qiov.size <= | |
1043 | QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size); | |
1044 | qemu_iovec_to_buf(&hd_qiov, 0, cluster_data, hd_qiov.size); | |
1045 | ||
1046 | qcow2_encrypt_sectors(s, sector_num, cluster_data, | |
1047 | cluster_data, cur_nr_sectors, 1, &s->aes_encrypt_key); | |
1048 | ||
1049 | qemu_iovec_reset(&hd_qiov); | |
1050 | qemu_iovec_add(&hd_qiov, cluster_data, | |
1051 | cur_nr_sectors * 512); | |
1052 | } | |
1053 | ||
1054 | ret = qcow2_pre_write_overlap_check(bs, 0, | |
1055 | cluster_offset + index_in_cluster * BDRV_SECTOR_SIZE, | |
1056 | cur_nr_sectors * BDRV_SECTOR_SIZE); | |
1057 | if (ret < 0) { | |
1058 | goto fail; | |
1059 | } | |
1060 | ||
1061 | qemu_co_mutex_unlock(&s->lock); | |
1062 | BLKDBG_EVENT(bs->file, BLKDBG_WRITE_AIO); | |
1063 | trace_qcow2_writev_data(qemu_coroutine_self(), | |
1064 | (cluster_offset >> 9) + index_in_cluster); | |
1065 | ret = bdrv_co_writev(bs->file, | |
1066 | (cluster_offset >> 9) + index_in_cluster, | |
1067 | cur_nr_sectors, &hd_qiov); | |
1068 | qemu_co_mutex_lock(&s->lock); | |
1069 | if (ret < 0) { | |
1070 | goto fail; | |
1071 | } | |
1072 | ||
1073 | while (l2meta != NULL) { | |
1074 | QCowL2Meta *next; | |
1075 | ||
1076 | ret = qcow2_alloc_cluster_link_l2(bs, l2meta); | |
1077 | if (ret < 0) { | |
1078 | goto fail; | |
1079 | } | |
1080 | ||
1081 | /* Take the request off the list of running requests */ | |
1082 | if (l2meta->nb_clusters != 0) { | |
1083 | QLIST_REMOVE(l2meta, next_in_flight); | |
1084 | } | |
1085 | ||
1086 | qemu_co_queue_restart_all(&l2meta->dependent_requests); | |
1087 | ||
1088 | next = l2meta->next; | |
1089 | g_free(l2meta); | |
1090 | l2meta = next; | |
1091 | } | |
1092 | ||
1093 | remaining_sectors -= cur_nr_sectors; | |
1094 | sector_num += cur_nr_sectors; | |
1095 | bytes_done += cur_nr_sectors * 512; | |
1096 | trace_qcow2_writev_done_part(qemu_coroutine_self(), cur_nr_sectors); | |
1097 | } | |
1098 | ret = 0; | |
1099 | ||
1100 | fail: | |
1101 | qemu_co_mutex_unlock(&s->lock); | |
1102 | ||
1103 | while (l2meta != NULL) { | |
1104 | QCowL2Meta *next; | |
1105 | ||
1106 | if (l2meta->nb_clusters != 0) { | |
1107 | QLIST_REMOVE(l2meta, next_in_flight); | |
1108 | } | |
1109 | qemu_co_queue_restart_all(&l2meta->dependent_requests); | |
1110 | ||
1111 | next = l2meta->next; | |
1112 | g_free(l2meta); | |
1113 | l2meta = next; | |
1114 | } | |
1115 | ||
1116 | qemu_iovec_destroy(&hd_qiov); | |
1117 | qemu_vfree(cluster_data); | |
1118 | trace_qcow2_writev_done_req(qemu_coroutine_self(), ret); | |
1119 | ||
1120 | return ret; | |
1121 | } | |
1122 | ||
1123 | static void qcow2_close(BlockDriverState *bs) | |
1124 | { | |
1125 | BDRVQcowState *s = bs->opaque; | |
1126 | g_free(s->l1_table); | |
1127 | /* else pre-write overlap checks in cache_destroy may crash */ | |
1128 | s->l1_table = NULL; | |
1129 | ||
1130 | qcow2_cache_flush(bs, s->l2_table_cache); | |
1131 | qcow2_cache_flush(bs, s->refcount_block_cache); | |
1132 | ||
1133 | qcow2_mark_clean(bs); | |
1134 | ||
1135 | qcow2_cache_destroy(bs, s->l2_table_cache); | |
1136 | qcow2_cache_destroy(bs, s->refcount_block_cache); | |
1137 | ||
1138 | g_free(s->unknown_header_fields); | |
1139 | cleanup_unknown_header_ext(bs); | |
1140 | ||
1141 | g_free(s->cluster_cache); | |
1142 | qemu_vfree(s->cluster_data); | |
1143 | qcow2_refcount_close(bs); | |
1144 | qcow2_free_snapshots(bs); | |
1145 | } | |
1146 | ||
1147 | static void qcow2_invalidate_cache(BlockDriverState *bs) | |
1148 | { | |
1149 | BDRVQcowState *s = bs->opaque; | |
1150 | int flags = s->flags; | |
1151 | AES_KEY aes_encrypt_key; | |
1152 | AES_KEY aes_decrypt_key; | |
1153 | uint32_t crypt_method = 0; | |
1154 | QDict *options; | |
1155 | ||
1156 | /* | |
1157 | * Backing files are read-only which makes all of their metadata immutable, | |
1158 | * that means we don't have to worry about reopening them here. | |
1159 | */ | |
1160 | ||
1161 | if (s->crypt_method) { | |
1162 | crypt_method = s->crypt_method; | |
1163 | memcpy(&aes_encrypt_key, &s->aes_encrypt_key, sizeof(aes_encrypt_key)); | |
1164 | memcpy(&aes_decrypt_key, &s->aes_decrypt_key, sizeof(aes_decrypt_key)); | |
1165 | } | |
1166 | ||
1167 | qcow2_close(bs); | |
1168 | ||
1169 | options = qdict_new(); | |
1170 | qdict_put(options, QCOW2_OPT_LAZY_REFCOUNTS, | |
1171 | qbool_from_int(s->use_lazy_refcounts)); | |
1172 | ||
1173 | memset(s, 0, sizeof(BDRVQcowState)); | |
1174 | qcow2_open(bs, options, flags, NULL); | |
1175 | ||
1176 | QDECREF(options); | |
1177 | ||
1178 | if (crypt_method) { | |
1179 | s->crypt_method = crypt_method; | |
1180 | memcpy(&s->aes_encrypt_key, &aes_encrypt_key, sizeof(aes_encrypt_key)); | |
1181 | memcpy(&s->aes_decrypt_key, &aes_decrypt_key, sizeof(aes_decrypt_key)); | |
1182 | } | |
1183 | } | |
1184 | ||
1185 | static size_t header_ext_add(char *buf, uint32_t magic, const void *s, | |
1186 | size_t len, size_t buflen) | |
1187 | { | |
1188 | QCowExtension *ext_backing_fmt = (QCowExtension*) buf; | |
1189 | size_t ext_len = sizeof(QCowExtension) + ((len + 7) & ~7); | |
1190 | ||
1191 | if (buflen < ext_len) { | |
1192 | return -ENOSPC; | |
1193 | } | |
1194 | ||
1195 | *ext_backing_fmt = (QCowExtension) { | |
1196 | .magic = cpu_to_be32(magic), | |
1197 | .len = cpu_to_be32(len), | |
1198 | }; | |
1199 | memcpy(buf + sizeof(QCowExtension), s, len); | |
1200 | ||
1201 | return ext_len; | |
1202 | } | |
1203 | ||
1204 | /* | |
1205 | * Updates the qcow2 header, including the variable length parts of it, i.e. | |
1206 | * the backing file name and all extensions. qcow2 was not designed to allow | |
1207 | * such changes, so if we run out of space (we can only use the first cluster) | |
1208 | * this function may fail. | |
1209 | * | |
1210 | * Returns 0 on success, -errno in error cases. | |
1211 | */ | |
1212 | int qcow2_update_header(BlockDriverState *bs) | |
1213 | { | |
1214 | BDRVQcowState *s = bs->opaque; | |
1215 | QCowHeader *header; | |
1216 | char *buf; | |
1217 | size_t buflen = s->cluster_size; | |
1218 | int ret; | |
1219 | uint64_t total_size; | |
1220 | uint32_t refcount_table_clusters; | |
1221 | size_t header_length; | |
1222 | Qcow2UnknownHeaderExtension *uext; | |
1223 | ||
1224 | buf = qemu_blockalign(bs, buflen); | |
1225 | ||
1226 | /* Header structure */ | |
1227 | header = (QCowHeader*) buf; | |
1228 | ||
1229 | if (buflen < sizeof(*header)) { | |
1230 | ret = -ENOSPC; | |
1231 | goto fail; | |
1232 | } | |
1233 | ||
1234 | header_length = sizeof(*header) + s->unknown_header_fields_size; | |
1235 | total_size = bs->total_sectors * BDRV_SECTOR_SIZE; | |
1236 | refcount_table_clusters = s->refcount_table_size >> (s->cluster_bits - 3); | |
1237 | ||
1238 | *header = (QCowHeader) { | |
1239 | /* Version 2 fields */ | |
1240 | .magic = cpu_to_be32(QCOW_MAGIC), | |
1241 | .version = cpu_to_be32(s->qcow_version), | |
1242 | .backing_file_offset = 0, | |
1243 | .backing_file_size = 0, | |
1244 | .cluster_bits = cpu_to_be32(s->cluster_bits), | |
1245 | .size = cpu_to_be64(total_size), | |
1246 | .crypt_method = cpu_to_be32(s->crypt_method_header), | |
1247 | .l1_size = cpu_to_be32(s->l1_size), | |
1248 | .l1_table_offset = cpu_to_be64(s->l1_table_offset), | |
1249 | .refcount_table_offset = cpu_to_be64(s->refcount_table_offset), | |
1250 | .refcount_table_clusters = cpu_to_be32(refcount_table_clusters), | |
1251 | .nb_snapshots = cpu_to_be32(s->nb_snapshots), | |
1252 | .snapshots_offset = cpu_to_be64(s->snapshots_offset), | |
1253 | ||
1254 | /* Version 3 fields */ | |
1255 | .incompatible_features = cpu_to_be64(s->incompatible_features), | |
1256 | .compatible_features = cpu_to_be64(s->compatible_features), | |
1257 | .autoclear_features = cpu_to_be64(s->autoclear_features), | |
1258 | .refcount_order = cpu_to_be32(s->refcount_order), | |
1259 | .header_length = cpu_to_be32(header_length), | |
1260 | }; | |
1261 | ||
1262 | /* For older versions, write a shorter header */ | |
1263 | switch (s->qcow_version) { | |
1264 | case 2: | |
1265 | ret = offsetof(QCowHeader, incompatible_features); | |
1266 | break; | |
1267 | case 3: | |
1268 | ret = sizeof(*header); | |
1269 | break; | |
1270 | default: | |
1271 | ret = -EINVAL; | |
1272 | goto fail; | |
1273 | } | |
1274 | ||
1275 | buf += ret; | |
1276 | buflen -= ret; | |
1277 | memset(buf, 0, buflen); | |
1278 | ||
1279 | /* Preserve any unknown field in the header */ | |
1280 | if (s->unknown_header_fields_size) { | |
1281 | if (buflen < s->unknown_header_fields_size) { | |
1282 | ret = -ENOSPC; | |
1283 | goto fail; | |
1284 | } | |
1285 | ||
1286 | memcpy(buf, s->unknown_header_fields, s->unknown_header_fields_size); | |
1287 | buf += s->unknown_header_fields_size; | |
1288 | buflen -= s->unknown_header_fields_size; | |
1289 | } | |
1290 | ||
1291 | /* Backing file format header extension */ | |
1292 | if (*bs->backing_format) { | |
1293 | ret = header_ext_add(buf, QCOW2_EXT_MAGIC_BACKING_FORMAT, | |
1294 | bs->backing_format, strlen(bs->backing_format), | |
1295 | buflen); | |
1296 | if (ret < 0) { | |
1297 | goto fail; | |
1298 | } | |
1299 | ||
1300 | buf += ret; | |
1301 | buflen -= ret; | |
1302 | } | |
1303 | ||
1304 | /* Feature table */ | |
1305 | Qcow2Feature features[] = { | |
1306 | { | |
1307 | .type = QCOW2_FEAT_TYPE_INCOMPATIBLE, | |
1308 | .bit = QCOW2_INCOMPAT_DIRTY_BITNR, | |
1309 | .name = "dirty bit", | |
1310 | }, | |
1311 | { | |
1312 | .type = QCOW2_FEAT_TYPE_INCOMPATIBLE, | |
1313 | .bit = QCOW2_INCOMPAT_CORRUPT_BITNR, | |
1314 | .name = "corrupt bit", | |
1315 | }, | |
1316 | { | |
1317 | .type = QCOW2_FEAT_TYPE_COMPATIBLE, | |
1318 | .bit = QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR, | |
1319 | .name = "lazy refcounts", | |
1320 | }, | |
1321 | }; | |
1322 | ||
1323 | ret = header_ext_add(buf, QCOW2_EXT_MAGIC_FEATURE_TABLE, | |
1324 | features, sizeof(features), buflen); | |
1325 | if (ret < 0) { | |
1326 | goto fail; | |
1327 | } | |
1328 | buf += ret; | |
1329 | buflen -= ret; | |
1330 | ||
1331 | /* Keep unknown header extensions */ | |
1332 | QLIST_FOREACH(uext, &s->unknown_header_ext, next) { | |
1333 | ret = header_ext_add(buf, uext->magic, uext->data, uext->len, buflen); | |
1334 | if (ret < 0) { | |
1335 | goto fail; | |
1336 | } | |
1337 | ||
1338 | buf += ret; | |
1339 | buflen -= ret; | |
1340 | } | |
1341 | ||
1342 | /* End of header extensions */ | |
1343 | ret = header_ext_add(buf, QCOW2_EXT_MAGIC_END, NULL, 0, buflen); | |
1344 | if (ret < 0) { | |
1345 | goto fail; | |
1346 | } | |
1347 | ||
1348 | buf += ret; | |
1349 | buflen -= ret; | |
1350 | ||
1351 | /* Backing file name */ | |
1352 | if (*bs->backing_file) { | |
1353 | size_t backing_file_len = strlen(bs->backing_file); | |
1354 | ||
1355 | if (buflen < backing_file_len) { | |
1356 | ret = -ENOSPC; | |
1357 | goto fail; | |
1358 | } | |
1359 | ||
1360 | /* Using strncpy is ok here, since buf is not NUL-terminated. */ | |
1361 | strncpy(buf, bs->backing_file, buflen); | |
1362 | ||
1363 | header->backing_file_offset = cpu_to_be64(buf - ((char*) header)); | |
1364 | header->backing_file_size = cpu_to_be32(backing_file_len); | |
1365 | } | |
1366 | ||
1367 | /* Write the new header */ | |
1368 | ret = bdrv_pwrite(bs->file, 0, header, s->cluster_size); | |
1369 | if (ret < 0) { | |
1370 | goto fail; | |
1371 | } | |
1372 | ||
1373 | ret = 0; | |
1374 | fail: | |
1375 | qemu_vfree(header); | |
1376 | return ret; | |
1377 | } | |
1378 | ||
1379 | static int qcow2_change_backing_file(BlockDriverState *bs, | |
1380 | const char *backing_file, const char *backing_fmt) | |
1381 | { | |
1382 | pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_file ?: ""); | |
1383 | pstrcpy(bs->backing_format, sizeof(bs->backing_format), backing_fmt ?: ""); | |
1384 | ||
1385 | return qcow2_update_header(bs); | |
1386 | } | |
1387 | ||
1388 | static int preallocate(BlockDriverState *bs) | |
1389 | { | |
1390 | uint64_t nb_sectors; | |
1391 | uint64_t offset; | |
1392 | uint64_t host_offset = 0; | |
1393 | int num; | |
1394 | int ret; | |
1395 | QCowL2Meta *meta; | |
1396 | ||
1397 | nb_sectors = bdrv_getlength(bs) >> 9; | |
1398 | offset = 0; | |
1399 | ||
1400 | while (nb_sectors) { | |
1401 | num = MIN(nb_sectors, INT_MAX >> 9); | |
1402 | ret = qcow2_alloc_cluster_offset(bs, offset, 0, num, &num, | |
1403 | &host_offset, &meta); | |
1404 | if (ret < 0) { | |
1405 | return ret; | |
1406 | } | |
1407 | ||
1408 | ret = qcow2_alloc_cluster_link_l2(bs, meta); | |
1409 | if (ret < 0) { | |
1410 | qcow2_free_any_clusters(bs, meta->alloc_offset, meta->nb_clusters, | |
1411 | QCOW2_DISCARD_NEVER); | |
1412 | return ret; | |
1413 | } | |
1414 | ||
1415 | /* There are no dependent requests, but we need to remove our request | |
1416 | * from the list of in-flight requests */ | |
1417 | if (meta != NULL) { | |
1418 | QLIST_REMOVE(meta, next_in_flight); | |
1419 | } | |
1420 | ||
1421 | /* TODO Preallocate data if requested */ | |
1422 | ||
1423 | nb_sectors -= num; | |
1424 | offset += num << 9; | |
1425 | } | |
1426 | ||
1427 | /* | |
1428 | * It is expected that the image file is large enough to actually contain | |
1429 | * all of the allocated clusters (otherwise we get failing reads after | |
1430 | * EOF). Extend the image to the last allocated sector. | |
1431 | */ | |
1432 | if (host_offset != 0) { | |
1433 | uint8_t buf[512]; | |
1434 | memset(buf, 0, 512); | |
1435 | ret = bdrv_write(bs->file, (host_offset >> 9) + num - 1, buf, 1); | |
1436 | if (ret < 0) { | |
1437 | return ret; | |
1438 | } | |
1439 | } | |
1440 | ||
1441 | return 0; | |
1442 | } | |
1443 | ||
1444 | static int qcow2_create2(const char *filename, int64_t total_size, | |
1445 | const char *backing_file, const char *backing_format, | |
1446 | int flags, size_t cluster_size, int prealloc, | |
1447 | QEMUOptionParameter *options, int version, | |
1448 | Error **errp) | |
1449 | { | |
1450 | /* Calculate cluster_bits */ | |
1451 | int cluster_bits; | |
1452 | cluster_bits = ffs(cluster_size) - 1; | |
1453 | if (cluster_bits < MIN_CLUSTER_BITS || cluster_bits > MAX_CLUSTER_BITS || | |
1454 | (1 << cluster_bits) != cluster_size) | |
1455 | { | |
1456 | error_setg(errp, "Cluster size must be a power of two between %d and " | |
1457 | "%dk", 1 << MIN_CLUSTER_BITS, 1 << (MAX_CLUSTER_BITS - 10)); | |
1458 | return -EINVAL; | |
1459 | } | |
1460 | ||
1461 | /* | |
1462 | * Open the image file and write a minimal qcow2 header. | |
1463 | * | |
1464 | * We keep things simple and start with a zero-sized image. We also | |
1465 | * do without refcount blocks or a L1 table for now. We'll fix the | |
1466 | * inconsistency later. | |
1467 | * | |
1468 | * We do need a refcount table because growing the refcount table means | |
1469 | * allocating two new refcount blocks - the seconds of which would be at | |
1470 | * 2 GB for 64k clusters, and we don't want to have a 2 GB initial file | |
1471 | * size for any qcow2 image. | |
1472 | */ | |
1473 | BlockDriverState* bs; | |
1474 | QCowHeader header; | |
1475 | uint8_t* refcount_table; | |
1476 | Error *local_err = NULL; | |
1477 | int ret; | |
1478 | ||
1479 | ret = bdrv_create_file(filename, options, &local_err); | |
1480 | if (ret < 0) { | |
1481 | error_propagate(errp, local_err); | |
1482 | return ret; | |
1483 | } | |
1484 | ||
1485 | ret = bdrv_file_open(&bs, filename, NULL, BDRV_O_RDWR, &local_err); | |
1486 | if (ret < 0) { | |
1487 | error_propagate(errp, local_err); | |
1488 | return ret; | |
1489 | } | |
1490 | ||
1491 | /* Write the header */ | |
1492 | memset(&header, 0, sizeof(header)); | |
1493 | header.magic = cpu_to_be32(QCOW_MAGIC); | |
1494 | header.version = cpu_to_be32(version); | |
1495 | header.cluster_bits = cpu_to_be32(cluster_bits); | |
1496 | header.size = cpu_to_be64(0); | |
1497 | header.l1_table_offset = cpu_to_be64(0); | |
1498 | header.l1_size = cpu_to_be32(0); | |
1499 | header.refcount_table_offset = cpu_to_be64(cluster_size); | |
1500 | header.refcount_table_clusters = cpu_to_be32(1); | |
1501 | header.refcount_order = cpu_to_be32(3 + REFCOUNT_SHIFT); | |
1502 | header.header_length = cpu_to_be32(sizeof(header)); | |
1503 | ||
1504 | if (flags & BLOCK_FLAG_ENCRYPT) { | |
1505 | header.crypt_method = cpu_to_be32(QCOW_CRYPT_AES); | |
1506 | } else { | |
1507 | header.crypt_method = cpu_to_be32(QCOW_CRYPT_NONE); | |
1508 | } | |
1509 | ||
1510 | if (flags & BLOCK_FLAG_LAZY_REFCOUNTS) { | |
1511 | header.compatible_features |= | |
1512 | cpu_to_be64(QCOW2_COMPAT_LAZY_REFCOUNTS); | |
1513 | } | |
1514 | ||
1515 | ret = bdrv_pwrite(bs, 0, &header, sizeof(header)); | |
1516 | if (ret < 0) { | |
1517 | error_setg_errno(errp, -ret, "Could not write qcow2 header"); | |
1518 | goto out; | |
1519 | } | |
1520 | ||
1521 | /* Write an empty refcount table */ | |
1522 | refcount_table = g_malloc0(cluster_size); | |
1523 | ret = bdrv_pwrite(bs, cluster_size, refcount_table, cluster_size); | |
1524 | g_free(refcount_table); | |
1525 | ||
1526 | if (ret < 0) { | |
1527 | error_setg_errno(errp, -ret, "Could not write refcount table"); | |
1528 | goto out; | |
1529 | } | |
1530 | ||
1531 | bdrv_close(bs); | |
1532 | ||
1533 | /* | |
1534 | * And now open the image and make it consistent first (i.e. increase the | |
1535 | * refcount of the cluster that is occupied by the header and the refcount | |
1536 | * table) | |
1537 | */ | |
1538 | BlockDriver* drv = bdrv_find_format("qcow2"); | |
1539 | assert(drv != NULL); | |
1540 | ret = bdrv_open(bs, filename, NULL, | |
1541 | BDRV_O_RDWR | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH, drv, &local_err); | |
1542 | if (ret < 0) { | |
1543 | error_propagate(errp, local_err); | |
1544 | goto out; | |
1545 | } | |
1546 | ||
1547 | ret = qcow2_alloc_clusters(bs, 2 * cluster_size); | |
1548 | if (ret < 0) { | |
1549 | error_setg_errno(errp, -ret, "Could not allocate clusters for qcow2 " | |
1550 | "header and refcount table"); | |
1551 | goto out; | |
1552 | ||
1553 | } else if (ret != 0) { | |
1554 | error_report("Huh, first cluster in empty image is already in use?"); | |
1555 | abort(); | |
1556 | } | |
1557 | ||
1558 | /* Okay, now that we have a valid image, let's give it the right size */ | |
1559 | ret = bdrv_truncate(bs, total_size * BDRV_SECTOR_SIZE); | |
1560 | if (ret < 0) { | |
1561 | error_setg_errno(errp, -ret, "Could not resize image"); | |
1562 | goto out; | |
1563 | } | |
1564 | ||
1565 | /* Want a backing file? There you go.*/ | |
1566 | if (backing_file) { | |
1567 | ret = bdrv_change_backing_file(bs, backing_file, backing_format); | |
1568 | if (ret < 0) { | |
1569 | error_setg_errno(errp, -ret, "Could not assign backing file '%s' " | |
1570 | "with format '%s'", backing_file, backing_format); | |
1571 | goto out; | |
1572 | } | |
1573 | } | |
1574 | ||
1575 | /* And if we're supposed to preallocate metadata, do that now */ | |
1576 | if (prealloc) { | |
1577 | BDRVQcowState *s = bs->opaque; | |
1578 | qemu_co_mutex_lock(&s->lock); | |
1579 | ret = preallocate(bs); | |
1580 | qemu_co_mutex_unlock(&s->lock); | |
1581 | if (ret < 0) { | |
1582 | error_setg_errno(errp, -ret, "Could not preallocate metadata"); | |
1583 | goto out; | |
1584 | } | |
1585 | } | |
1586 | ||
1587 | bdrv_close(bs); | |
1588 | ||
1589 | /* Reopen the image without BDRV_O_NO_FLUSH to flush it before returning */ | |
1590 | ret = bdrv_open(bs, filename, NULL, | |
1591 | BDRV_O_RDWR | BDRV_O_CACHE_WB, drv, &local_err); | |
1592 | if (error_is_set(&local_err)) { | |
1593 | error_propagate(errp, local_err); | |
1594 | goto out; | |
1595 | } | |
1596 | ||
1597 | ret = 0; | |
1598 | out: | |
1599 | bdrv_unref(bs); | |
1600 | return ret; | |
1601 | } | |
1602 | ||
1603 | static int qcow2_create(const char *filename, QEMUOptionParameter *options, | |
1604 | Error **errp) | |
1605 | { | |
1606 | const char *backing_file = NULL; | |
1607 | const char *backing_fmt = NULL; | |
1608 | uint64_t sectors = 0; | |
1609 | int flags = 0; | |
1610 | size_t cluster_size = DEFAULT_CLUSTER_SIZE; | |
1611 | int prealloc = 0; | |
1612 | int version = 3; | |
1613 | Error *local_err = NULL; | |
1614 | int ret; | |
1615 | ||
1616 | /* Read out options */ | |
1617 | while (options && options->name) { | |
1618 | if (!strcmp(options->name, BLOCK_OPT_SIZE)) { | |
1619 | sectors = options->value.n / 512; | |
1620 | } else if (!strcmp(options->name, BLOCK_OPT_BACKING_FILE)) { | |
1621 | backing_file = options->value.s; | |
1622 | } else if (!strcmp(options->name, BLOCK_OPT_BACKING_FMT)) { | |
1623 | backing_fmt = options->value.s; | |
1624 | } else if (!strcmp(options->name, BLOCK_OPT_ENCRYPT)) { | |
1625 | flags |= options->value.n ? BLOCK_FLAG_ENCRYPT : 0; | |
1626 | } else if (!strcmp(options->name, BLOCK_OPT_CLUSTER_SIZE)) { | |
1627 | if (options->value.n) { | |
1628 | cluster_size = options->value.n; | |
1629 | } | |
1630 | } else if (!strcmp(options->name, BLOCK_OPT_PREALLOC)) { | |
1631 | if (!options->value.s || !strcmp(options->value.s, "off")) { | |
1632 | prealloc = 0; | |
1633 | } else if (!strcmp(options->value.s, "metadata")) { | |
1634 | prealloc = 1; | |
1635 | } else { | |
1636 | error_setg(errp, "Invalid preallocation mode: '%s'", | |
1637 | options->value.s); | |
1638 | return -EINVAL; | |
1639 | } | |
1640 | } else if (!strcmp(options->name, BLOCK_OPT_COMPAT_LEVEL)) { | |
1641 | if (!options->value.s) { | |
1642 | /* keep the default */ | |
1643 | } else if (!strcmp(options->value.s, "0.10")) { | |
1644 | version = 2; | |
1645 | } else if (!strcmp(options->value.s, "1.1")) { | |
1646 | version = 3; | |
1647 | } else { | |
1648 | error_setg(errp, "Invalid compatibility level: '%s'", | |
1649 | options->value.s); | |
1650 | return -EINVAL; | |
1651 | } | |
1652 | } else if (!strcmp(options->name, BLOCK_OPT_LAZY_REFCOUNTS)) { | |
1653 | flags |= options->value.n ? BLOCK_FLAG_LAZY_REFCOUNTS : 0; | |
1654 | } | |
1655 | options++; | |
1656 | } | |
1657 | ||
1658 | if (backing_file && prealloc) { | |
1659 | error_setg(errp, "Backing file and preallocation cannot be used at " | |
1660 | "the same time"); | |
1661 | return -EINVAL; | |
1662 | } | |
1663 | ||
1664 | if (version < 3 && (flags & BLOCK_FLAG_LAZY_REFCOUNTS)) { | |
1665 | error_setg(errp, "Lazy refcounts only supported with compatibility " | |
1666 | "level 1.1 and above (use compat=1.1 or greater)"); | |
1667 | return -EINVAL; | |
1668 | } | |
1669 | ||
1670 | ret = qcow2_create2(filename, sectors, backing_file, backing_fmt, flags, | |
1671 | cluster_size, prealloc, options, version, &local_err); | |
1672 | if (error_is_set(&local_err)) { | |
1673 | error_propagate(errp, local_err); | |
1674 | } | |
1675 | return ret; | |
1676 | } | |
1677 | ||
1678 | static int qcow2_make_empty(BlockDriverState *bs) | |
1679 | { | |
1680 | #if 0 | |
1681 | /* XXX: not correct */ | |
1682 | BDRVQcowState *s = bs->opaque; | |
1683 | uint32_t l1_length = s->l1_size * sizeof(uint64_t); | |
1684 | int ret; | |
1685 | ||
1686 | memset(s->l1_table, 0, l1_length); | |
1687 | if (bdrv_pwrite(bs->file, s->l1_table_offset, s->l1_table, l1_length) < 0) | |
1688 | return -1; | |
1689 | ret = bdrv_truncate(bs->file, s->l1_table_offset + l1_length); | |
1690 | if (ret < 0) | |
1691 | return ret; | |
1692 | ||
1693 | l2_cache_reset(bs); | |
1694 | #endif | |
1695 | return 0; | |
1696 | } | |
1697 | ||
1698 | static coroutine_fn int qcow2_co_write_zeroes(BlockDriverState *bs, | |
1699 | int64_t sector_num, int nb_sectors) | |
1700 | { | |
1701 | int ret; | |
1702 | BDRVQcowState *s = bs->opaque; | |
1703 | ||
1704 | /* Emulate misaligned zero writes */ | |
1705 | if (sector_num % s->cluster_sectors || nb_sectors % s->cluster_sectors) { | |
1706 | return -ENOTSUP; | |
1707 | } | |
1708 | ||
1709 | /* Whatever is left can use real zero clusters */ | |
1710 | qemu_co_mutex_lock(&s->lock); | |
1711 | ret = qcow2_zero_clusters(bs, sector_num << BDRV_SECTOR_BITS, | |
1712 | nb_sectors); | |
1713 | qemu_co_mutex_unlock(&s->lock); | |
1714 | ||
1715 | return ret; | |
1716 | } | |
1717 | ||
1718 | static coroutine_fn int qcow2_co_discard(BlockDriverState *bs, | |
1719 | int64_t sector_num, int nb_sectors) | |
1720 | { | |
1721 | int ret; | |
1722 | BDRVQcowState *s = bs->opaque; | |
1723 | ||
1724 | qemu_co_mutex_lock(&s->lock); | |
1725 | ret = qcow2_discard_clusters(bs, sector_num << BDRV_SECTOR_BITS, | |
1726 | nb_sectors, QCOW2_DISCARD_REQUEST); | |
1727 | qemu_co_mutex_unlock(&s->lock); | |
1728 | return ret; | |
1729 | } | |
1730 | ||
1731 | static int qcow2_truncate(BlockDriverState *bs, int64_t offset) | |
1732 | { | |
1733 | BDRVQcowState *s = bs->opaque; | |
1734 | int64_t new_l1_size; | |
1735 | int ret; | |
1736 | ||
1737 | if (offset & 511) { | |
1738 | error_report("The new size must be a multiple of 512"); | |
1739 | return -EINVAL; | |
1740 | } | |
1741 | ||
1742 | /* cannot proceed if image has snapshots */ | |
1743 | if (s->nb_snapshots) { | |
1744 | error_report("Can't resize an image which has snapshots"); | |
1745 | return -ENOTSUP; | |
1746 | } | |
1747 | ||
1748 | /* shrinking is currently not supported */ | |
1749 | if (offset < bs->total_sectors * 512) { | |
1750 | error_report("qcow2 doesn't support shrinking images yet"); | |
1751 | return -ENOTSUP; | |
1752 | } | |
1753 | ||
1754 | new_l1_size = size_to_l1(s, offset); | |
1755 | ret = qcow2_grow_l1_table(bs, new_l1_size, true); | |
1756 | if (ret < 0) { | |
1757 | return ret; | |
1758 | } | |
1759 | ||
1760 | /* write updated header.size */ | |
1761 | offset = cpu_to_be64(offset); | |
1762 | ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, size), | |
1763 | &offset, sizeof(uint64_t)); | |
1764 | if (ret < 0) { | |
1765 | return ret; | |
1766 | } | |
1767 | ||
1768 | s->l1_vm_state_index = new_l1_size; | |
1769 | return 0; | |
1770 | } | |
1771 | ||
1772 | /* XXX: put compressed sectors first, then all the cluster aligned | |
1773 | tables to avoid losing bytes in alignment */ | |
1774 | static int qcow2_write_compressed(BlockDriverState *bs, int64_t sector_num, | |
1775 | const uint8_t *buf, int nb_sectors) | |
1776 | { | |
1777 | BDRVQcowState *s = bs->opaque; | |
1778 | z_stream strm; | |
1779 | int ret, out_len; | |
1780 | uint8_t *out_buf; | |
1781 | uint64_t cluster_offset; | |
1782 | ||
1783 | if (nb_sectors == 0) { | |
1784 | /* align end of file to a sector boundary to ease reading with | |
1785 | sector based I/Os */ | |
1786 | cluster_offset = bdrv_getlength(bs->file); | |
1787 | cluster_offset = (cluster_offset + 511) & ~511; | |
1788 | bdrv_truncate(bs->file, cluster_offset); | |
1789 | return 0; | |
1790 | } | |
1791 | ||
1792 | if (nb_sectors != s->cluster_sectors) { | |
1793 | ret = -EINVAL; | |
1794 | ||
1795 | /* Zero-pad last write if image size is not cluster aligned */ | |
1796 | if (sector_num + nb_sectors == bs->total_sectors && | |
1797 | nb_sectors < s->cluster_sectors) { | |
1798 | uint8_t *pad_buf = qemu_blockalign(bs, s->cluster_size); | |
1799 | memset(pad_buf, 0, s->cluster_size); | |
1800 | memcpy(pad_buf, buf, nb_sectors * BDRV_SECTOR_SIZE); | |
1801 | ret = qcow2_write_compressed(bs, sector_num, | |
1802 | pad_buf, s->cluster_sectors); | |
1803 | qemu_vfree(pad_buf); | |
1804 | } | |
1805 | return ret; | |
1806 | } | |
1807 | ||
1808 | out_buf = g_malloc(s->cluster_size + (s->cluster_size / 1000) + 128); | |
1809 | ||
1810 | /* best compression, small window, no zlib header */ | |
1811 | memset(&strm, 0, sizeof(strm)); | |
1812 | ret = deflateInit2(&strm, Z_DEFAULT_COMPRESSION, | |
1813 | Z_DEFLATED, -12, | |
1814 | 9, Z_DEFAULT_STRATEGY); | |
1815 | if (ret != 0) { | |
1816 | ret = -EINVAL; | |
1817 | goto fail; | |
1818 | } | |
1819 | ||
1820 | strm.avail_in = s->cluster_size; | |
1821 | strm.next_in = (uint8_t *)buf; | |
1822 | strm.avail_out = s->cluster_size; | |
1823 | strm.next_out = out_buf; | |
1824 | ||
1825 | ret = deflate(&strm, Z_FINISH); | |
1826 | if (ret != Z_STREAM_END && ret != Z_OK) { | |
1827 | deflateEnd(&strm); | |
1828 | ret = -EINVAL; | |
1829 | goto fail; | |
1830 | } | |
1831 | out_len = strm.next_out - out_buf; | |
1832 | ||
1833 | deflateEnd(&strm); | |
1834 | ||
1835 | if (ret != Z_STREAM_END || out_len >= s->cluster_size) { | |
1836 | /* could not compress: write normal cluster */ | |
1837 | ret = bdrv_write(bs, sector_num, buf, s->cluster_sectors); | |
1838 | if (ret < 0) { | |
1839 | goto fail; | |
1840 | } | |
1841 | } else { | |
1842 | cluster_offset = qcow2_alloc_compressed_cluster_offset(bs, | |
1843 | sector_num << 9, out_len); | |
1844 | if (!cluster_offset) { | |
1845 | ret = -EIO; | |
1846 | goto fail; | |
1847 | } | |
1848 | cluster_offset &= s->cluster_offset_mask; | |
1849 | ||
1850 | ret = qcow2_pre_write_overlap_check(bs, 0, cluster_offset, out_len); | |
1851 | if (ret < 0) { | |
1852 | goto fail; | |
1853 | } | |
1854 | ||
1855 | BLKDBG_EVENT(bs->file, BLKDBG_WRITE_COMPRESSED); | |
1856 | ret = bdrv_pwrite(bs->file, cluster_offset, out_buf, out_len); | |
1857 | if (ret < 0) { | |
1858 | goto fail; | |
1859 | } | |
1860 | } | |
1861 | ||
1862 | ret = 0; | |
1863 | fail: | |
1864 | g_free(out_buf); | |
1865 | return ret; | |
1866 | } | |
1867 | ||
1868 | static coroutine_fn int qcow2_co_flush_to_os(BlockDriverState *bs) | |
1869 | { | |
1870 | BDRVQcowState *s = bs->opaque; | |
1871 | int ret; | |
1872 | ||
1873 | qemu_co_mutex_lock(&s->lock); | |
1874 | ret = qcow2_cache_flush(bs, s->l2_table_cache); | |
1875 | if (ret < 0) { | |
1876 | qemu_co_mutex_unlock(&s->lock); | |
1877 | return ret; | |
1878 | } | |
1879 | ||
1880 | if (qcow2_need_accurate_refcounts(s)) { | |
1881 | ret = qcow2_cache_flush(bs, s->refcount_block_cache); | |
1882 | if (ret < 0) { | |
1883 | qemu_co_mutex_unlock(&s->lock); | |
1884 | return ret; | |
1885 | } | |
1886 | } | |
1887 | qemu_co_mutex_unlock(&s->lock); | |
1888 | ||
1889 | return 0; | |
1890 | } | |
1891 | ||
1892 | static int qcow2_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) | |
1893 | { | |
1894 | BDRVQcowState *s = bs->opaque; | |
1895 | bdi->cluster_size = s->cluster_size; | |
1896 | bdi->vm_state_offset = qcow2_vm_state_offset(s); | |
1897 | return 0; | |
1898 | } | |
1899 | ||
1900 | static ImageInfoSpecific *qcow2_get_specific_info(BlockDriverState *bs) | |
1901 | { | |
1902 | BDRVQcowState *s = bs->opaque; | |
1903 | ImageInfoSpecific *spec_info = g_new(ImageInfoSpecific, 1); | |
1904 | ||
1905 | *spec_info = (ImageInfoSpecific){ | |
1906 | .kind = IMAGE_INFO_SPECIFIC_KIND_QCOW2, | |
1907 | { | |
1908 | .qcow2 = g_new(ImageInfoSpecificQCow2, 1), | |
1909 | }, | |
1910 | }; | |
1911 | if (s->qcow_version == 2) { | |
1912 | *spec_info->qcow2 = (ImageInfoSpecificQCow2){ | |
1913 | .compat = g_strdup("0.10"), | |
1914 | }; | |
1915 | } else if (s->qcow_version == 3) { | |
1916 | *spec_info->qcow2 = (ImageInfoSpecificQCow2){ | |
1917 | .compat = g_strdup("1.1"), | |
1918 | .lazy_refcounts = s->compatible_features & | |
1919 | QCOW2_COMPAT_LAZY_REFCOUNTS, | |
1920 | .has_lazy_refcounts = true, | |
1921 | }; | |
1922 | } | |
1923 | ||
1924 | return spec_info; | |
1925 | } | |
1926 | ||
1927 | #if 0 | |
1928 | static void dump_refcounts(BlockDriverState *bs) | |
1929 | { | |
1930 | BDRVQcowState *s = bs->opaque; | |
1931 | int64_t nb_clusters, k, k1, size; | |
1932 | int refcount; | |
1933 | ||
1934 | size = bdrv_getlength(bs->file); | |
1935 | nb_clusters = size_to_clusters(s, size); | |
1936 | for(k = 0; k < nb_clusters;) { | |
1937 | k1 = k; | |
1938 | refcount = get_refcount(bs, k); | |
1939 | k++; | |
1940 | while (k < nb_clusters && get_refcount(bs, k) == refcount) | |
1941 | k++; | |
1942 | printf("%" PRId64 ": refcount=%d nb=%" PRId64 "\n", k, refcount, | |
1943 | k - k1); | |
1944 | } | |
1945 | } | |
1946 | #endif | |
1947 | ||
1948 | static int qcow2_save_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, | |
1949 | int64_t pos) | |
1950 | { | |
1951 | BDRVQcowState *s = bs->opaque; | |
1952 | int64_t total_sectors = bs->total_sectors; | |
1953 | int growable = bs->growable; | |
1954 | bool zero_beyond_eof = bs->zero_beyond_eof; | |
1955 | int ret; | |
1956 | ||
1957 | BLKDBG_EVENT(bs->file, BLKDBG_VMSTATE_SAVE); | |
1958 | bs->growable = 1; | |
1959 | bs->zero_beyond_eof = false; | |
1960 | ret = bdrv_pwritev(bs, qcow2_vm_state_offset(s) + pos, qiov); | |
1961 | bs->growable = growable; | |
1962 | bs->zero_beyond_eof = zero_beyond_eof; | |
1963 | ||
1964 | /* bdrv_co_do_writev will have increased the total_sectors value to include | |
1965 | * the VM state - the VM state is however not an actual part of the block | |
1966 | * device, therefore, we need to restore the old value. */ | |
1967 | bs->total_sectors = total_sectors; | |
1968 | ||
1969 | return ret; | |
1970 | } | |
1971 | ||
1972 | static int qcow2_load_vmstate(BlockDriverState *bs, uint8_t *buf, | |
1973 | int64_t pos, int size) | |
1974 | { | |
1975 | BDRVQcowState *s = bs->opaque; | |
1976 | int growable = bs->growable; | |
1977 | bool zero_beyond_eof = bs->zero_beyond_eof; | |
1978 | int ret; | |
1979 | ||
1980 | BLKDBG_EVENT(bs->file, BLKDBG_VMSTATE_LOAD); | |
1981 | bs->growable = 1; | |
1982 | bs->zero_beyond_eof = false; | |
1983 | ret = bdrv_pread(bs, qcow2_vm_state_offset(s) + pos, buf, size); | |
1984 | bs->growable = growable; | |
1985 | bs->zero_beyond_eof = zero_beyond_eof; | |
1986 | ||
1987 | return ret; | |
1988 | } | |
1989 | ||
1990 | /* | |
1991 | * Downgrades an image's version. To achieve this, any incompatible features | |
1992 | * have to be removed. | |
1993 | */ | |
1994 | static int qcow2_downgrade(BlockDriverState *bs, int target_version) | |
1995 | { | |
1996 | BDRVQcowState *s = bs->opaque; | |
1997 | int current_version = s->qcow_version; | |
1998 | int ret; | |
1999 | ||
2000 | if (target_version == current_version) { | |
2001 | return 0; | |
2002 | } else if (target_version > current_version) { | |
2003 | return -EINVAL; | |
2004 | } else if (target_version != 2) { | |
2005 | return -EINVAL; | |
2006 | } | |
2007 | ||
2008 | if (s->refcount_order != 4) { | |
2009 | /* we would have to convert the image to a refcount_order == 4 image | |
2010 | * here; however, since qemu (at the time of writing this) does not | |
2011 | * support anything different than 4 anyway, there is no point in doing | |
2012 | * so right now; however, we should error out (if qemu supports this in | |
2013 | * the future and this code has not been adapted) */ | |
2014 | error_report("qcow2_downgrade: Image refcount orders other than 4 are " | |
2015 | "currently not supported."); | |
2016 | return -ENOTSUP; | |
2017 | } | |
2018 | ||
2019 | /* clear incompatible features */ | |
2020 | if (s->incompatible_features & QCOW2_INCOMPAT_DIRTY) { | |
2021 | ret = qcow2_mark_clean(bs); | |
2022 | if (ret < 0) { | |
2023 | return ret; | |
2024 | } | |
2025 | } | |
2026 | ||
2027 | /* with QCOW2_INCOMPAT_CORRUPT, it is pretty much impossible to get here in | |
2028 | * the first place; if that happens nonetheless, returning -ENOTSUP is the | |
2029 | * best thing to do anyway */ | |
2030 | ||
2031 | if (s->incompatible_features) { | |
2032 | return -ENOTSUP; | |
2033 | } | |
2034 | ||
2035 | /* since we can ignore compatible features, we can set them to 0 as well */ | |
2036 | s->compatible_features = 0; | |
2037 | /* if lazy refcounts have been used, they have already been fixed through | |
2038 | * clearing the dirty flag */ | |
2039 | ||
2040 | /* clearing autoclear features is trivial */ | |
2041 | s->autoclear_features = 0; | |
2042 | ||
2043 | ret = qcow2_expand_zero_clusters(bs); | |
2044 | if (ret < 0) { | |
2045 | return ret; | |
2046 | } | |
2047 | ||
2048 | s->qcow_version = target_version; | |
2049 | ret = qcow2_update_header(bs); | |
2050 | if (ret < 0) { | |
2051 | s->qcow_version = current_version; | |
2052 | return ret; | |
2053 | } | |
2054 | return 0; | |
2055 | } | |
2056 | ||
2057 | static int qcow2_amend_options(BlockDriverState *bs, | |
2058 | QEMUOptionParameter *options) | |
2059 | { | |
2060 | BDRVQcowState *s = bs->opaque; | |
2061 | int old_version = s->qcow_version, new_version = old_version; | |
2062 | uint64_t new_size = 0; | |
2063 | const char *backing_file = NULL, *backing_format = NULL; | |
2064 | bool lazy_refcounts = s->use_lazy_refcounts; | |
2065 | int ret; | |
2066 | int i; | |
2067 | ||
2068 | for (i = 0; options[i].name; i++) | |
2069 | { | |
2070 | if (!options[i].assigned) { | |
2071 | /* only change explicitly defined options */ | |
2072 | continue; | |
2073 | } | |
2074 | ||
2075 | if (!strcmp(options[i].name, "compat")) { | |
2076 | if (!options[i].value.s) { | |
2077 | /* preserve default */ | |
2078 | } else if (!strcmp(options[i].value.s, "0.10")) { | |
2079 | new_version = 2; | |
2080 | } else if (!strcmp(options[i].value.s, "1.1")) { | |
2081 | new_version = 3; | |
2082 | } else { | |
2083 | fprintf(stderr, "Unknown compatibility level %s.\n", | |
2084 | options[i].value.s); | |
2085 | return -EINVAL; | |
2086 | } | |
2087 | } else if (!strcmp(options[i].name, "preallocation")) { | |
2088 | fprintf(stderr, "Cannot change preallocation mode.\n"); | |
2089 | return -ENOTSUP; | |
2090 | } else if (!strcmp(options[i].name, "size")) { | |
2091 | new_size = options[i].value.n; | |
2092 | } else if (!strcmp(options[i].name, "backing_file")) { | |
2093 | backing_file = options[i].value.s; | |
2094 | } else if (!strcmp(options[i].name, "backing_fmt")) { | |
2095 | backing_format = options[i].value.s; | |
2096 | } else if (!strcmp(options[i].name, "encryption")) { | |
2097 | if ((options[i].value.n != !!s->crypt_method)) { | |
2098 | fprintf(stderr, "Changing the encryption flag is not " | |
2099 | "supported.\n"); | |
2100 | return -ENOTSUP; | |
2101 | } | |
2102 | } else if (!strcmp(options[i].name, "cluster_size")) { | |
2103 | if (options[i].value.n != s->cluster_size) { | |
2104 | fprintf(stderr, "Changing the cluster size is not " | |
2105 | "supported.\n"); | |
2106 | return -ENOTSUP; | |
2107 | } | |
2108 | } else if (!strcmp(options[i].name, "lazy_refcounts")) { | |
2109 | lazy_refcounts = options[i].value.n; | |
2110 | } else { | |
2111 | /* if this assertion fails, this probably means a new option was | |
2112 | * added without having it covered here */ | |
2113 | assert(false); | |
2114 | } | |
2115 | } | |
2116 | ||
2117 | if (new_version != old_version) { | |
2118 | if (new_version > old_version) { | |
2119 | /* Upgrade */ | |
2120 | s->qcow_version = new_version; | |
2121 | ret = qcow2_update_header(bs); | |
2122 | if (ret < 0) { | |
2123 | s->qcow_version = old_version; | |
2124 | return ret; | |
2125 | } | |
2126 | } else { | |
2127 | ret = qcow2_downgrade(bs, new_version); | |
2128 | if (ret < 0) { | |
2129 | return ret; | |
2130 | } | |
2131 | } | |
2132 | } | |
2133 | ||
2134 | if (backing_file || backing_format) { | |
2135 | ret = qcow2_change_backing_file(bs, backing_file ?: bs->backing_file, | |
2136 | backing_format ?: bs->backing_format); | |
2137 | if (ret < 0) { | |
2138 | return ret; | |
2139 | } | |
2140 | } | |
2141 | ||
2142 | if (s->use_lazy_refcounts != lazy_refcounts) { | |
2143 | if (lazy_refcounts) { | |
2144 | if (s->qcow_version < 3) { | |
2145 | fprintf(stderr, "Lazy refcounts only supported with compatibility " | |
2146 | "level 1.1 and above (use compat=1.1 or greater)\n"); | |
2147 | return -EINVAL; | |
2148 | } | |
2149 | s->compatible_features |= QCOW2_COMPAT_LAZY_REFCOUNTS; | |
2150 | ret = qcow2_update_header(bs); | |
2151 | if (ret < 0) { | |
2152 | s->compatible_features &= ~QCOW2_COMPAT_LAZY_REFCOUNTS; | |
2153 | return ret; | |
2154 | } | |
2155 | s->use_lazy_refcounts = true; | |
2156 | } else { | |
2157 | /* make image clean first */ | |
2158 | ret = qcow2_mark_clean(bs); | |
2159 | if (ret < 0) { | |
2160 | return ret; | |
2161 | } | |
2162 | /* now disallow lazy refcounts */ | |
2163 | s->compatible_features &= ~QCOW2_COMPAT_LAZY_REFCOUNTS; | |
2164 | ret = qcow2_update_header(bs); | |
2165 | if (ret < 0) { | |
2166 | s->compatible_features |= QCOW2_COMPAT_LAZY_REFCOUNTS; | |
2167 | return ret; | |
2168 | } | |
2169 | s->use_lazy_refcounts = false; | |
2170 | } | |
2171 | } | |
2172 | ||
2173 | if (new_size) { | |
2174 | ret = bdrv_truncate(bs, new_size); | |
2175 | if (ret < 0) { | |
2176 | return ret; | |
2177 | } | |
2178 | } | |
2179 | ||
2180 | return 0; | |
2181 | } | |
2182 | ||
2183 | static QEMUOptionParameter qcow2_create_options[] = { | |
2184 | { | |
2185 | .name = BLOCK_OPT_SIZE, | |
2186 | .type = OPT_SIZE, | |
2187 | .help = "Virtual disk size" | |
2188 | }, | |
2189 | { | |
2190 | .name = BLOCK_OPT_COMPAT_LEVEL, | |
2191 | .type = OPT_STRING, | |
2192 | .help = "Compatibility level (0.10 or 1.1)" | |
2193 | }, | |
2194 | { | |
2195 | .name = BLOCK_OPT_BACKING_FILE, | |
2196 | .type = OPT_STRING, | |
2197 | .help = "File name of a base image" | |
2198 | }, | |
2199 | { | |
2200 | .name = BLOCK_OPT_BACKING_FMT, | |
2201 | .type = OPT_STRING, | |
2202 | .help = "Image format of the base image" | |
2203 | }, | |
2204 | { | |
2205 | .name = BLOCK_OPT_ENCRYPT, | |
2206 | .type = OPT_FLAG, | |
2207 | .help = "Encrypt the image" | |
2208 | }, | |
2209 | { | |
2210 | .name = BLOCK_OPT_CLUSTER_SIZE, | |
2211 | .type = OPT_SIZE, | |
2212 | .help = "qcow2 cluster size", | |
2213 | .value = { .n = DEFAULT_CLUSTER_SIZE }, | |
2214 | }, | |
2215 | { | |
2216 | .name = BLOCK_OPT_PREALLOC, | |
2217 | .type = OPT_STRING, | |
2218 | .help = "Preallocation mode (allowed values: off, metadata)" | |
2219 | }, | |
2220 | { | |
2221 | .name = BLOCK_OPT_LAZY_REFCOUNTS, | |
2222 | .type = OPT_FLAG, | |
2223 | .help = "Postpone refcount updates", | |
2224 | }, | |
2225 | { NULL } | |
2226 | }; | |
2227 | ||
2228 | static BlockDriver bdrv_qcow2 = { | |
2229 | .format_name = "qcow2", | |
2230 | .instance_size = sizeof(BDRVQcowState), | |
2231 | .bdrv_probe = qcow2_probe, | |
2232 | .bdrv_open = qcow2_open, | |
2233 | .bdrv_close = qcow2_close, | |
2234 | .bdrv_reopen_prepare = qcow2_reopen_prepare, | |
2235 | .bdrv_create = qcow2_create, | |
2236 | .bdrv_has_zero_init = bdrv_has_zero_init_1, | |
2237 | .bdrv_co_get_block_status = qcow2_co_get_block_status, | |
2238 | .bdrv_set_key = qcow2_set_key, | |
2239 | .bdrv_make_empty = qcow2_make_empty, | |
2240 | ||
2241 | .bdrv_co_readv = qcow2_co_readv, | |
2242 | .bdrv_co_writev = qcow2_co_writev, | |
2243 | .bdrv_co_flush_to_os = qcow2_co_flush_to_os, | |
2244 | ||
2245 | .bdrv_co_write_zeroes = qcow2_co_write_zeroes, | |
2246 | .bdrv_co_discard = qcow2_co_discard, | |
2247 | .bdrv_truncate = qcow2_truncate, | |
2248 | .bdrv_write_compressed = qcow2_write_compressed, | |
2249 | ||
2250 | .bdrv_snapshot_create = qcow2_snapshot_create, | |
2251 | .bdrv_snapshot_goto = qcow2_snapshot_goto, | |
2252 | .bdrv_snapshot_delete = qcow2_snapshot_delete, | |
2253 | .bdrv_snapshot_list = qcow2_snapshot_list, | |
2254 | .bdrv_snapshot_load_tmp = qcow2_snapshot_load_tmp, | |
2255 | .bdrv_get_info = qcow2_get_info, | |
2256 | .bdrv_get_specific_info = qcow2_get_specific_info, | |
2257 | ||
2258 | .bdrv_save_vmstate = qcow2_save_vmstate, | |
2259 | .bdrv_load_vmstate = qcow2_load_vmstate, | |
2260 | ||
2261 | .bdrv_change_backing_file = qcow2_change_backing_file, | |
2262 | ||
2263 | .bdrv_invalidate_cache = qcow2_invalidate_cache, | |
2264 | ||
2265 | .create_options = qcow2_create_options, | |
2266 | .bdrv_check = qcow2_check, | |
2267 | .bdrv_amend_options = qcow2_amend_options, | |
2268 | }; | |
2269 | ||
2270 | static void bdrv_qcow2_init(void) | |
2271 | { | |
2272 | bdrv_register(&bdrv_qcow2); | |
2273 | } | |
2274 | ||
2275 | block_init(bdrv_qcow2_init); |