Merge remote-tracking branch 'remotes/kraxel/tags/pull-vga-20170103-1' into staging
[qemu.git] / block / dmg.c
1 /*
2 * QEMU Block driver for DMG images
3 *
4 * Copyright (c) 2004 Johannes E. Schindelin
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/osdep.h"
25 #include "qapi/error.h"
26 #include "qemu-common.h"
27 #include "block/block_int.h"
28 #include "qemu/bswap.h"
29 #include "qemu/error-report.h"
30 #include "qemu/module.h"
31 #include "dmg.h"
32
33 int (*dmg_uncompress_bz2)(char *next_in, unsigned int avail_in,
34 char *next_out, unsigned int avail_out);
35
36 enum {
37 /* Limit chunk sizes to prevent unreasonable amounts of memory being used
38 * or truncating when converting to 32-bit types
39 */
40 DMG_LENGTHS_MAX = 64 * 1024 * 1024, /* 64 MB */
41 DMG_SECTORCOUNTS_MAX = DMG_LENGTHS_MAX / 512,
42 };
43
44 static int dmg_probe(const uint8_t *buf, int buf_size, const char *filename)
45 {
46 int len;
47
48 if (!filename) {
49 return 0;
50 }
51
52 len = strlen(filename);
53 if (len > 4 && !strcmp(filename + len - 4, ".dmg")) {
54 return 2;
55 }
56 return 0;
57 }
58
59 static int read_uint64(BlockDriverState *bs, int64_t offset, uint64_t *result)
60 {
61 uint64_t buffer;
62 int ret;
63
64 ret = bdrv_pread(bs->file, offset, &buffer, 8);
65 if (ret < 0) {
66 return ret;
67 }
68
69 *result = be64_to_cpu(buffer);
70 return 0;
71 }
72
73 static int read_uint32(BlockDriverState *bs, int64_t offset, uint32_t *result)
74 {
75 uint32_t buffer;
76 int ret;
77
78 ret = bdrv_pread(bs->file, offset, &buffer, 4);
79 if (ret < 0) {
80 return ret;
81 }
82
83 *result = be32_to_cpu(buffer);
84 return 0;
85 }
86
87 static inline uint64_t buff_read_uint64(const uint8_t *buffer, int64_t offset)
88 {
89 return be64_to_cpu(*(uint64_t *)&buffer[offset]);
90 }
91
92 static inline uint32_t buff_read_uint32(const uint8_t *buffer, int64_t offset)
93 {
94 return be32_to_cpu(*(uint32_t *)&buffer[offset]);
95 }
96
97 /* Increase max chunk sizes, if necessary. This function is used to calculate
98 * the buffer sizes needed for compressed/uncompressed chunk I/O.
99 */
100 static void update_max_chunk_size(BDRVDMGState *s, uint32_t chunk,
101 uint32_t *max_compressed_size,
102 uint32_t *max_sectors_per_chunk)
103 {
104 uint32_t compressed_size = 0;
105 uint32_t uncompressed_sectors = 0;
106
107 switch (s->types[chunk]) {
108 case 0x80000005: /* zlib compressed */
109 case 0x80000006: /* bzip2 compressed */
110 compressed_size = s->lengths[chunk];
111 uncompressed_sectors = s->sectorcounts[chunk];
112 break;
113 case 1: /* copy */
114 uncompressed_sectors = (s->lengths[chunk] + 511) / 512;
115 break;
116 case 2: /* zero */
117 /* as the all-zeroes block may be large, it is treated specially: the
118 * sector is not copied from a large buffer, a simple memset is used
119 * instead. Therefore uncompressed_sectors does not need to be set. */
120 break;
121 }
122
123 if (compressed_size > *max_compressed_size) {
124 *max_compressed_size = compressed_size;
125 }
126 if (uncompressed_sectors > *max_sectors_per_chunk) {
127 *max_sectors_per_chunk = uncompressed_sectors;
128 }
129 }
130
131 static int64_t dmg_find_koly_offset(BdrvChild *file, Error **errp)
132 {
133 BlockDriverState *file_bs = file->bs;
134 int64_t length;
135 int64_t offset = 0;
136 uint8_t buffer[515];
137 int i, ret;
138
139 /* bdrv_getlength returns a multiple of block size (512), rounded up. Since
140 * dmg images can have odd sizes, try to look for the "koly" magic which
141 * marks the begin of the UDIF trailer (512 bytes). This magic can be found
142 * in the last 511 bytes of the second-last sector or the first 4 bytes of
143 * the last sector (search space: 515 bytes) */
144 length = bdrv_getlength(file_bs);
145 if (length < 0) {
146 error_setg_errno(errp, -length,
147 "Failed to get file size while reading UDIF trailer");
148 return length;
149 } else if (length < 512) {
150 error_setg(errp, "dmg file must be at least 512 bytes long");
151 return -EINVAL;
152 }
153 if (length > 511 + 512) {
154 offset = length - 511 - 512;
155 }
156 length = length < 515 ? length : 515;
157 ret = bdrv_pread(file, offset, buffer, length);
158 if (ret < 0) {
159 error_setg_errno(errp, -ret, "Failed while reading UDIF trailer");
160 return ret;
161 }
162 for (i = 0; i < length - 3; i++) {
163 if (buffer[i] == 'k' && buffer[i+1] == 'o' &&
164 buffer[i+2] == 'l' && buffer[i+3] == 'y') {
165 return offset + i;
166 }
167 }
168 error_setg(errp, "Could not locate UDIF trailer in dmg file");
169 return -EINVAL;
170 }
171
172 /* used when building the sector table */
173 typedef struct DmgHeaderState {
174 /* used internally by dmg_read_mish_block to remember offsets of blocks
175 * across calls */
176 uint64_t data_fork_offset;
177 /* exported for dmg_open */
178 uint32_t max_compressed_size;
179 uint32_t max_sectors_per_chunk;
180 } DmgHeaderState;
181
182 static bool dmg_is_known_block_type(uint32_t entry_type)
183 {
184 switch (entry_type) {
185 case 0x00000001: /* uncompressed */
186 case 0x00000002: /* zeroes */
187 case 0x80000005: /* zlib */
188 return true;
189 case 0x80000006: /* bzip2 */
190 return !!dmg_uncompress_bz2;
191 default:
192 return false;
193 }
194 }
195
196 static int dmg_read_mish_block(BDRVDMGState *s, DmgHeaderState *ds,
197 uint8_t *buffer, uint32_t count)
198 {
199 uint32_t type, i;
200 int ret;
201 size_t new_size;
202 uint32_t chunk_count;
203 int64_t offset = 0;
204 uint64_t data_offset;
205 uint64_t in_offset = ds->data_fork_offset;
206 uint64_t out_offset;
207
208 type = buff_read_uint32(buffer, offset);
209 /* skip data that is not a valid MISH block (invalid magic or too small) */
210 if (type != 0x6d697368 || count < 244) {
211 /* assume success for now */
212 return 0;
213 }
214
215 /* chunk offsets are relative to this sector number */
216 out_offset = buff_read_uint64(buffer, offset + 8);
217
218 /* location in data fork for (compressed) blob (in bytes) */
219 data_offset = buff_read_uint64(buffer, offset + 0x18);
220 in_offset += data_offset;
221
222 /* move to begin of chunk entries */
223 offset += 204;
224
225 chunk_count = (count - 204) / 40;
226 new_size = sizeof(uint64_t) * (s->n_chunks + chunk_count);
227 s->types = g_realloc(s->types, new_size / 2);
228 s->offsets = g_realloc(s->offsets, new_size);
229 s->lengths = g_realloc(s->lengths, new_size);
230 s->sectors = g_realloc(s->sectors, new_size);
231 s->sectorcounts = g_realloc(s->sectorcounts, new_size);
232
233 for (i = s->n_chunks; i < s->n_chunks + chunk_count; i++) {
234 s->types[i] = buff_read_uint32(buffer, offset);
235 if (!dmg_is_known_block_type(s->types[i])) {
236 chunk_count--;
237 i--;
238 offset += 40;
239 continue;
240 }
241
242 /* sector number */
243 s->sectors[i] = buff_read_uint64(buffer, offset + 8);
244 s->sectors[i] += out_offset;
245
246 /* sector count */
247 s->sectorcounts[i] = buff_read_uint64(buffer, offset + 0x10);
248
249 /* all-zeroes sector (type 2) does not need to be "uncompressed" and can
250 * therefore be unbounded. */
251 if (s->types[i] != 2 && s->sectorcounts[i] > DMG_SECTORCOUNTS_MAX) {
252 error_report("sector count %" PRIu64 " for chunk %" PRIu32
253 " is larger than max (%u)",
254 s->sectorcounts[i], i, DMG_SECTORCOUNTS_MAX);
255 ret = -EINVAL;
256 goto fail;
257 }
258
259 /* offset in (compressed) data fork */
260 s->offsets[i] = buff_read_uint64(buffer, offset + 0x18);
261 s->offsets[i] += in_offset;
262
263 /* length in (compressed) data fork */
264 s->lengths[i] = buff_read_uint64(buffer, offset + 0x20);
265
266 if (s->lengths[i] > DMG_LENGTHS_MAX) {
267 error_report("length %" PRIu64 " for chunk %" PRIu32
268 " is larger than max (%u)",
269 s->lengths[i], i, DMG_LENGTHS_MAX);
270 ret = -EINVAL;
271 goto fail;
272 }
273
274 update_max_chunk_size(s, i, &ds->max_compressed_size,
275 &ds->max_sectors_per_chunk);
276 offset += 40;
277 }
278 s->n_chunks += chunk_count;
279 return 0;
280
281 fail:
282 return ret;
283 }
284
285 static int dmg_read_resource_fork(BlockDriverState *bs, DmgHeaderState *ds,
286 uint64_t info_begin, uint64_t info_length)
287 {
288 BDRVDMGState *s = bs->opaque;
289 int ret;
290 uint32_t count, rsrc_data_offset;
291 uint8_t *buffer = NULL;
292 uint64_t info_end;
293 uint64_t offset;
294
295 /* read offset from begin of resource fork (info_begin) to resource data */
296 ret = read_uint32(bs, info_begin, &rsrc_data_offset);
297 if (ret < 0) {
298 goto fail;
299 } else if (rsrc_data_offset > info_length) {
300 ret = -EINVAL;
301 goto fail;
302 }
303
304 /* read length of resource data */
305 ret = read_uint32(bs, info_begin + 8, &count);
306 if (ret < 0) {
307 goto fail;
308 } else if (count == 0 || rsrc_data_offset + count > info_length) {
309 ret = -EINVAL;
310 goto fail;
311 }
312
313 /* begin of resource data (consisting of one or more resources) */
314 offset = info_begin + rsrc_data_offset;
315
316 /* end of resource data (there is possibly a following resource map
317 * which will be ignored). */
318 info_end = offset + count;
319
320 /* read offsets (mish blocks) from one or more resources in resource data */
321 while (offset < info_end) {
322 /* size of following resource */
323 ret = read_uint32(bs, offset, &count);
324 if (ret < 0) {
325 goto fail;
326 } else if (count == 0 || count > info_end - offset) {
327 ret = -EINVAL;
328 goto fail;
329 }
330 offset += 4;
331
332 buffer = g_realloc(buffer, count);
333 ret = bdrv_pread(bs->file, offset, buffer, count);
334 if (ret < 0) {
335 goto fail;
336 }
337
338 ret = dmg_read_mish_block(s, ds, buffer, count);
339 if (ret < 0) {
340 goto fail;
341 }
342 /* advance offset by size of resource */
343 offset += count;
344 }
345 ret = 0;
346
347 fail:
348 g_free(buffer);
349 return ret;
350 }
351
352 static int dmg_read_plist_xml(BlockDriverState *bs, DmgHeaderState *ds,
353 uint64_t info_begin, uint64_t info_length)
354 {
355 BDRVDMGState *s = bs->opaque;
356 int ret;
357 uint8_t *buffer = NULL;
358 char *data_begin, *data_end;
359
360 /* Have at least some length to avoid NULL for g_malloc. Attempt to set a
361 * safe upper cap on the data length. A test sample had a XML length of
362 * about 1 MiB. */
363 if (info_length == 0 || info_length > 16 * 1024 * 1024) {
364 ret = -EINVAL;
365 goto fail;
366 }
367
368 buffer = g_malloc(info_length + 1);
369 buffer[info_length] = '\0';
370 ret = bdrv_pread(bs->file, info_begin, buffer, info_length);
371 if (ret != info_length) {
372 ret = -EINVAL;
373 goto fail;
374 }
375
376 /* look for <data>...</data>. The data is 284 (0x11c) bytes after base64
377 * decode. The actual data element has 431 (0x1af) bytes which includes tabs
378 * and line feeds. */
379 data_end = (char *)buffer;
380 while ((data_begin = strstr(data_end, "<data>")) != NULL) {
381 guchar *mish;
382 gsize out_len = 0;
383
384 data_begin += 6;
385 data_end = strstr(data_begin, "</data>");
386 /* malformed XML? */
387 if (data_end == NULL) {
388 ret = -EINVAL;
389 goto fail;
390 }
391 *data_end++ = '\0';
392 mish = g_base64_decode(data_begin, &out_len);
393 ret = dmg_read_mish_block(s, ds, mish, (uint32_t)out_len);
394 g_free(mish);
395 if (ret < 0) {
396 goto fail;
397 }
398 }
399 ret = 0;
400
401 fail:
402 g_free(buffer);
403 return ret;
404 }
405
406 static int dmg_open(BlockDriverState *bs, QDict *options, int flags,
407 Error **errp)
408 {
409 BDRVDMGState *s = bs->opaque;
410 DmgHeaderState ds;
411 uint64_t rsrc_fork_offset, rsrc_fork_length;
412 uint64_t plist_xml_offset, plist_xml_length;
413 int64_t offset;
414 int ret;
415
416 block_module_load_one("dmg-bz2");
417 bs->read_only = true;
418
419 s->n_chunks = 0;
420 s->offsets = s->lengths = s->sectors = s->sectorcounts = NULL;
421 /* used by dmg_read_mish_block to keep track of the current I/O position */
422 ds.data_fork_offset = 0;
423 ds.max_compressed_size = 1;
424 ds.max_sectors_per_chunk = 1;
425
426 /* locate the UDIF trailer */
427 offset = dmg_find_koly_offset(bs->file, errp);
428 if (offset < 0) {
429 ret = offset;
430 goto fail;
431 }
432
433 /* offset of data fork (DataForkOffset) */
434 ret = read_uint64(bs, offset + 0x18, &ds.data_fork_offset);
435 if (ret < 0) {
436 goto fail;
437 } else if (ds.data_fork_offset > offset) {
438 ret = -EINVAL;
439 goto fail;
440 }
441
442 /* offset of resource fork (RsrcForkOffset) */
443 ret = read_uint64(bs, offset + 0x28, &rsrc_fork_offset);
444 if (ret < 0) {
445 goto fail;
446 }
447 ret = read_uint64(bs, offset + 0x30, &rsrc_fork_length);
448 if (ret < 0) {
449 goto fail;
450 }
451 if (rsrc_fork_offset >= offset ||
452 rsrc_fork_length > offset - rsrc_fork_offset) {
453 ret = -EINVAL;
454 goto fail;
455 }
456 /* offset of property list (XMLOffset) */
457 ret = read_uint64(bs, offset + 0xd8, &plist_xml_offset);
458 if (ret < 0) {
459 goto fail;
460 }
461 ret = read_uint64(bs, offset + 0xe0, &plist_xml_length);
462 if (ret < 0) {
463 goto fail;
464 }
465 if (plist_xml_offset >= offset ||
466 plist_xml_length > offset - plist_xml_offset) {
467 ret = -EINVAL;
468 goto fail;
469 }
470 ret = read_uint64(bs, offset + 0x1ec, (uint64_t *)&bs->total_sectors);
471 if (ret < 0) {
472 goto fail;
473 }
474 if (bs->total_sectors < 0) {
475 ret = -EINVAL;
476 goto fail;
477 }
478 if (rsrc_fork_length != 0) {
479 ret = dmg_read_resource_fork(bs, &ds,
480 rsrc_fork_offset, rsrc_fork_length);
481 if (ret < 0) {
482 goto fail;
483 }
484 } else if (plist_xml_length != 0) {
485 ret = dmg_read_plist_xml(bs, &ds, plist_xml_offset, plist_xml_length);
486 if (ret < 0) {
487 goto fail;
488 }
489 } else {
490 ret = -EINVAL;
491 goto fail;
492 }
493
494 /* initialize zlib engine */
495 s->compressed_chunk = qemu_try_blockalign(bs->file->bs,
496 ds.max_compressed_size + 1);
497 s->uncompressed_chunk = qemu_try_blockalign(bs->file->bs,
498 512 * ds.max_sectors_per_chunk);
499 if (s->compressed_chunk == NULL || s->uncompressed_chunk == NULL) {
500 ret = -ENOMEM;
501 goto fail;
502 }
503
504 if (inflateInit(&s->zstream) != Z_OK) {
505 ret = -EINVAL;
506 goto fail;
507 }
508
509 s->current_chunk = s->n_chunks;
510
511 qemu_co_mutex_init(&s->lock);
512 return 0;
513
514 fail:
515 g_free(s->types);
516 g_free(s->offsets);
517 g_free(s->lengths);
518 g_free(s->sectors);
519 g_free(s->sectorcounts);
520 qemu_vfree(s->compressed_chunk);
521 qemu_vfree(s->uncompressed_chunk);
522 return ret;
523 }
524
525 static void dmg_refresh_limits(BlockDriverState *bs, Error **errp)
526 {
527 bs->bl.request_alignment = BDRV_SECTOR_SIZE; /* No sub-sector I/O */
528 }
529
530 static inline int is_sector_in_chunk(BDRVDMGState* s,
531 uint32_t chunk_num, uint64_t sector_num)
532 {
533 if (chunk_num >= s->n_chunks || s->sectors[chunk_num] > sector_num ||
534 s->sectors[chunk_num] + s->sectorcounts[chunk_num] <= sector_num) {
535 return 0;
536 } else {
537 return -1;
538 }
539 }
540
541 static inline uint32_t search_chunk(BDRVDMGState *s, uint64_t sector_num)
542 {
543 /* binary search */
544 uint32_t chunk1 = 0, chunk2 = s->n_chunks, chunk3;
545 while (chunk1 != chunk2) {
546 chunk3 = (chunk1 + chunk2) / 2;
547 if (s->sectors[chunk3] > sector_num) {
548 chunk2 = chunk3;
549 } else if (s->sectors[chunk3] + s->sectorcounts[chunk3] > sector_num) {
550 return chunk3;
551 } else {
552 chunk1 = chunk3;
553 }
554 }
555 return s->n_chunks; /* error */
556 }
557
558 static inline int dmg_read_chunk(BlockDriverState *bs, uint64_t sector_num)
559 {
560 BDRVDMGState *s = bs->opaque;
561
562 if (!is_sector_in_chunk(s, s->current_chunk, sector_num)) {
563 int ret;
564 uint32_t chunk = search_chunk(s, sector_num);
565
566 if (chunk >= s->n_chunks) {
567 return -1;
568 }
569
570 s->current_chunk = s->n_chunks;
571 switch (s->types[chunk]) { /* block entry type */
572 case 0x80000005: { /* zlib compressed */
573 /* we need to buffer, because only the chunk as whole can be
574 * inflated. */
575 ret = bdrv_pread(bs->file, s->offsets[chunk],
576 s->compressed_chunk, s->lengths[chunk]);
577 if (ret != s->lengths[chunk]) {
578 return -1;
579 }
580
581 s->zstream.next_in = s->compressed_chunk;
582 s->zstream.avail_in = s->lengths[chunk];
583 s->zstream.next_out = s->uncompressed_chunk;
584 s->zstream.avail_out = 512 * s->sectorcounts[chunk];
585 ret = inflateReset(&s->zstream);
586 if (ret != Z_OK) {
587 return -1;
588 }
589 ret = inflate(&s->zstream, Z_FINISH);
590 if (ret != Z_STREAM_END ||
591 s->zstream.total_out != 512 * s->sectorcounts[chunk]) {
592 return -1;
593 }
594 break; }
595 case 0x80000006: /* bzip2 compressed */
596 if (!dmg_uncompress_bz2) {
597 break;
598 }
599 /* we need to buffer, because only the chunk as whole can be
600 * inflated. */
601 ret = bdrv_pread(bs->file, s->offsets[chunk],
602 s->compressed_chunk, s->lengths[chunk]);
603 if (ret != s->lengths[chunk]) {
604 return -1;
605 }
606
607 ret = dmg_uncompress_bz2((char *)s->compressed_chunk,
608 (unsigned int) s->lengths[chunk],
609 (char *)s->uncompressed_chunk,
610 (unsigned int)
611 (512 * s->sectorcounts[chunk]));
612 if (ret < 0) {
613 return ret;
614 }
615 break;
616 case 1: /* copy */
617 ret = bdrv_pread(bs->file, s->offsets[chunk],
618 s->uncompressed_chunk, s->lengths[chunk]);
619 if (ret != s->lengths[chunk]) {
620 return -1;
621 }
622 break;
623 case 2: /* zero */
624 /* see dmg_read, it is treated specially. No buffer needs to be
625 * pre-filled, the zeroes can be set directly. */
626 break;
627 }
628 s->current_chunk = chunk;
629 }
630 return 0;
631 }
632
633 static int coroutine_fn
634 dmg_co_preadv(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
635 QEMUIOVector *qiov, int flags)
636 {
637 BDRVDMGState *s = bs->opaque;
638 uint64_t sector_num = offset >> BDRV_SECTOR_BITS;
639 int nb_sectors = bytes >> BDRV_SECTOR_BITS;
640 int ret, i;
641
642 assert((offset & (BDRV_SECTOR_SIZE - 1)) == 0);
643 assert((bytes & (BDRV_SECTOR_SIZE - 1)) == 0);
644
645 qemu_co_mutex_lock(&s->lock);
646
647 for (i = 0; i < nb_sectors; i++) {
648 uint32_t sector_offset_in_chunk;
649 void *data;
650
651 if (dmg_read_chunk(bs, sector_num + i) != 0) {
652 ret = -EIO;
653 goto fail;
654 }
655 /* Special case: current chunk is all zeroes. Do not perform a memcpy as
656 * s->uncompressed_chunk may be too small to cover the large all-zeroes
657 * section. dmg_read_chunk is called to find s->current_chunk */
658 if (s->types[s->current_chunk] == 2) { /* all zeroes block entry */
659 qemu_iovec_memset(qiov, i * 512, 0, 512);
660 continue;
661 }
662 sector_offset_in_chunk = sector_num + i - s->sectors[s->current_chunk];
663 data = s->uncompressed_chunk + sector_offset_in_chunk * 512;
664 qemu_iovec_from_buf(qiov, i * 512, data, 512);
665 }
666
667 ret = 0;
668 fail:
669 qemu_co_mutex_unlock(&s->lock);
670 return ret;
671 }
672
673 static void dmg_close(BlockDriverState *bs)
674 {
675 BDRVDMGState *s = bs->opaque;
676
677 g_free(s->types);
678 g_free(s->offsets);
679 g_free(s->lengths);
680 g_free(s->sectors);
681 g_free(s->sectorcounts);
682 qemu_vfree(s->compressed_chunk);
683 qemu_vfree(s->uncompressed_chunk);
684
685 inflateEnd(&s->zstream);
686 }
687
688 static BlockDriver bdrv_dmg = {
689 .format_name = "dmg",
690 .instance_size = sizeof(BDRVDMGState),
691 .bdrv_probe = dmg_probe,
692 .bdrv_open = dmg_open,
693 .bdrv_refresh_limits = dmg_refresh_limits,
694 .bdrv_co_preadv = dmg_co_preadv,
695 .bdrv_close = dmg_close,
696 };
697
698 static void bdrv_dmg_init(void)
699 {
700 bdrv_register(&bdrv_dmg);
701 }
702
703 block_init(bdrv_dmg_init);