Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging
[qemu.git] / block / vpc.c
1 /*
2 * Block driver for Connectix / Microsoft Virtual PC images
3 *
4 * Copyright (c) 2005 Alex Beregszaszi
5 * Copyright (c) 2009 Kevin Wolf <kwolf@suse.de>
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a copy
8 * of this software and associated documentation files (the "Software"), to deal
9 * in the Software without restriction, including without limitation the rights
10 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11 * copies of the Software, and to permit persons to whom the Software is
12 * furnished to do so, subject to the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be included in
15 * all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23 * THE SOFTWARE.
24 */
25 #include "qemu-common.h"
26 #include "block/block_int.h"
27 #include "qemu/module.h"
28 #include "migration/migration.h"
29 #if defined(CONFIG_UUID)
30 #include <uuid/uuid.h>
31 #endif
32
33 /**************************************************************/
34
35 #define HEADER_SIZE 512
36
37 //#define CACHE
38
39 enum vhd_type {
40 VHD_FIXED = 2,
41 VHD_DYNAMIC = 3,
42 VHD_DIFFERENCING = 4,
43 };
44
45 // Seconds since Jan 1, 2000 0:00:00 (UTC)
46 #define VHD_TIMESTAMP_BASE 946684800
47
48 // always big-endian
49 typedef struct vhd_footer {
50 char creator[8]; // "conectix"
51 uint32_t features;
52 uint32_t version;
53
54 // Offset of next header structure, 0xFFFFFFFF if none
55 uint64_t data_offset;
56
57 // Seconds since Jan 1, 2000 0:00:00 (UTC)
58 uint32_t timestamp;
59
60 char creator_app[4]; // "vpc "
61 uint16_t major;
62 uint16_t minor;
63 char creator_os[4]; // "Wi2k"
64
65 uint64_t orig_size;
66 uint64_t size;
67
68 uint16_t cyls;
69 uint8_t heads;
70 uint8_t secs_per_cyl;
71
72 uint32_t type;
73
74 // Checksum of the Hard Disk Footer ("one's complement of the sum of all
75 // the bytes in the footer without the checksum field")
76 uint32_t checksum;
77
78 // UUID used to identify a parent hard disk (backing file)
79 uint8_t uuid[16];
80
81 uint8_t in_saved_state;
82 } QEMU_PACKED VHDFooter;
83
84 typedef struct vhd_dyndisk_header {
85 char magic[8]; // "cxsparse"
86
87 // Offset of next header structure, 0xFFFFFFFF if none
88 uint64_t data_offset;
89
90 // Offset of the Block Allocation Table (BAT)
91 uint64_t table_offset;
92
93 uint32_t version;
94 uint32_t max_table_entries; // 32bit/entry
95
96 // 2 MB by default, must be a power of two
97 uint32_t block_size;
98
99 uint32_t checksum;
100 uint8_t parent_uuid[16];
101 uint32_t parent_timestamp;
102 uint32_t reserved;
103
104 // Backing file name (in UTF-16)
105 uint8_t parent_name[512];
106
107 struct {
108 uint32_t platform;
109 uint32_t data_space;
110 uint32_t data_length;
111 uint32_t reserved;
112 uint64_t data_offset;
113 } parent_locator[8];
114 } QEMU_PACKED VHDDynDiskHeader;
115
116 typedef struct BDRVVPCState {
117 CoMutex lock;
118 uint8_t footer_buf[HEADER_SIZE];
119 uint64_t free_data_block_offset;
120 int max_table_entries;
121 uint32_t *pagetable;
122 uint64_t bat_offset;
123 uint64_t last_bitmap_offset;
124
125 uint32_t block_size;
126 uint32_t bitmap_size;
127
128 #ifdef CACHE
129 uint8_t *pageentry_u8;
130 uint32_t *pageentry_u32;
131 uint16_t *pageentry_u16;
132
133 uint64_t last_bitmap;
134 #endif
135
136 Error *migration_blocker;
137 } BDRVVPCState;
138
139 static uint32_t vpc_checksum(uint8_t* buf, size_t size)
140 {
141 uint32_t res = 0;
142 int i;
143
144 for (i = 0; i < size; i++)
145 res += buf[i];
146
147 return ~res;
148 }
149
150
151 static int vpc_probe(const uint8_t *buf, int buf_size, const char *filename)
152 {
153 if (buf_size >= 8 && !strncmp((char *)buf, "conectix", 8))
154 return 100;
155 return 0;
156 }
157
158 static int vpc_open(BlockDriverState *bs, QDict *options, int flags,
159 Error **errp)
160 {
161 BDRVVPCState *s = bs->opaque;
162 int i;
163 VHDFooter *footer;
164 VHDDynDiskHeader *dyndisk_header;
165 uint8_t buf[HEADER_SIZE];
166 uint32_t checksum;
167 int disk_type = VHD_DYNAMIC;
168 int ret;
169
170 ret = bdrv_pread(bs->file, 0, s->footer_buf, HEADER_SIZE);
171 if (ret < 0) {
172 goto fail;
173 }
174
175 footer = (VHDFooter *) s->footer_buf;
176 if (strncmp(footer->creator, "conectix", 8)) {
177 int64_t offset = bdrv_getlength(bs->file);
178 if (offset < 0) {
179 ret = offset;
180 goto fail;
181 } else if (offset < HEADER_SIZE) {
182 ret = -EINVAL;
183 goto fail;
184 }
185
186 /* If a fixed disk, the footer is found only at the end of the file */
187 ret = bdrv_pread(bs->file, offset-HEADER_SIZE, s->footer_buf,
188 HEADER_SIZE);
189 if (ret < 0) {
190 goto fail;
191 }
192 if (strncmp(footer->creator, "conectix", 8)) {
193 error_setg(errp, "invalid VPC image");
194 ret = -EINVAL;
195 goto fail;
196 }
197 disk_type = VHD_FIXED;
198 }
199
200 checksum = be32_to_cpu(footer->checksum);
201 footer->checksum = 0;
202 if (vpc_checksum(s->footer_buf, HEADER_SIZE) != checksum)
203 fprintf(stderr, "block-vpc: The header checksum of '%s' is "
204 "incorrect.\n", bs->filename);
205
206 /* Write 'checksum' back to footer, or else will leave it with zero. */
207 footer->checksum = be32_to_cpu(checksum);
208
209 // The visible size of a image in Virtual PC depends on the geometry
210 // rather than on the size stored in the footer (the size in the footer
211 // is too large usually)
212 bs->total_sectors = (int64_t)
213 be16_to_cpu(footer->cyls) * footer->heads * footer->secs_per_cyl;
214
215 /* images created with disk2vhd report a far higher virtual size
216 * than expected with the cyls * heads * sectors_per_cyl formula.
217 * use the footer->size instead if the image was created with
218 * disk2vhd.
219 */
220 if (!strncmp(footer->creator_app, "d2v", 4)) {
221 bs->total_sectors = be64_to_cpu(footer->size) / BDRV_SECTOR_SIZE;
222 }
223
224 /* Allow a maximum disk size of approximately 2 TB */
225 if (bs->total_sectors >= 65535LL * 255 * 255) {
226 ret = -EFBIG;
227 goto fail;
228 }
229
230 if (disk_type == VHD_DYNAMIC) {
231 ret = bdrv_pread(bs->file, be64_to_cpu(footer->data_offset), buf,
232 HEADER_SIZE);
233 if (ret < 0) {
234 goto fail;
235 }
236
237 dyndisk_header = (VHDDynDiskHeader *) buf;
238
239 if (strncmp(dyndisk_header->magic, "cxsparse", 8)) {
240 ret = -EINVAL;
241 goto fail;
242 }
243
244 s->block_size = be32_to_cpu(dyndisk_header->block_size);
245 s->bitmap_size = ((s->block_size / (8 * 512)) + 511) & ~511;
246
247 s->max_table_entries = be32_to_cpu(dyndisk_header->max_table_entries);
248 s->pagetable = g_malloc(s->max_table_entries * 4);
249
250 s->bat_offset = be64_to_cpu(dyndisk_header->table_offset);
251
252 ret = bdrv_pread(bs->file, s->bat_offset, s->pagetable,
253 s->max_table_entries * 4);
254 if (ret < 0) {
255 goto fail;
256 }
257
258 s->free_data_block_offset =
259 (s->bat_offset + (s->max_table_entries * 4) + 511) & ~511;
260
261 for (i = 0; i < s->max_table_entries; i++) {
262 be32_to_cpus(&s->pagetable[i]);
263 if (s->pagetable[i] != 0xFFFFFFFF) {
264 int64_t next = (512 * (int64_t) s->pagetable[i]) +
265 s->bitmap_size + s->block_size;
266
267 if (next > s->free_data_block_offset) {
268 s->free_data_block_offset = next;
269 }
270 }
271 }
272
273 if (s->free_data_block_offset > bdrv_getlength(bs->file)) {
274 error_setg(errp, "block-vpc: free_data_block_offset points after "
275 "the end of file. The image has been truncated.");
276 ret = -EINVAL;
277 goto fail;
278 }
279
280 s->last_bitmap_offset = (int64_t) -1;
281
282 #ifdef CACHE
283 s->pageentry_u8 = g_malloc(512);
284 s->pageentry_u32 = s->pageentry_u8;
285 s->pageentry_u16 = s->pageentry_u8;
286 s->last_pagetable = -1;
287 #endif
288 }
289
290 qemu_co_mutex_init(&s->lock);
291
292 /* Disable migration when VHD images are used */
293 error_set(&s->migration_blocker,
294 QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED,
295 "vpc", bs->device_name, "live migration");
296 migrate_add_blocker(s->migration_blocker);
297
298 return 0;
299
300 fail:
301 g_free(s->pagetable);
302 #ifdef CACHE
303 g_free(s->pageentry_u8);
304 #endif
305 return ret;
306 }
307
308 static int vpc_reopen_prepare(BDRVReopenState *state,
309 BlockReopenQueue *queue, Error **errp)
310 {
311 return 0;
312 }
313
314 /*
315 * Returns the absolute byte offset of the given sector in the image file.
316 * If the sector is not allocated, -1 is returned instead.
317 *
318 * The parameter write must be 1 if the offset will be used for a write
319 * operation (the block bitmaps is updated then), 0 otherwise.
320 */
321 static inline int64_t get_sector_offset(BlockDriverState *bs,
322 int64_t sector_num, int write)
323 {
324 BDRVVPCState *s = bs->opaque;
325 uint64_t offset = sector_num * 512;
326 uint64_t bitmap_offset, block_offset;
327 uint32_t pagetable_index, pageentry_index;
328
329 pagetable_index = offset / s->block_size;
330 pageentry_index = (offset % s->block_size) / 512;
331
332 if (pagetable_index >= s->max_table_entries || s->pagetable[pagetable_index] == 0xffffffff)
333 return -1; // not allocated
334
335 bitmap_offset = 512 * (uint64_t) s->pagetable[pagetable_index];
336 block_offset = bitmap_offset + s->bitmap_size + (512 * pageentry_index);
337
338 // We must ensure that we don't write to any sectors which are marked as
339 // unused in the bitmap. We get away with setting all bits in the block
340 // bitmap each time we write to a new block. This might cause Virtual PC to
341 // miss sparse read optimization, but it's not a problem in terms of
342 // correctness.
343 if (write && (s->last_bitmap_offset != bitmap_offset)) {
344 uint8_t bitmap[s->bitmap_size];
345
346 s->last_bitmap_offset = bitmap_offset;
347 memset(bitmap, 0xff, s->bitmap_size);
348 bdrv_pwrite_sync(bs->file, bitmap_offset, bitmap, s->bitmap_size);
349 }
350
351 // printf("sector: %" PRIx64 ", index: %x, offset: %x, bioff: %" PRIx64 ", bloff: %" PRIx64 "\n",
352 // sector_num, pagetable_index, pageentry_index,
353 // bitmap_offset, block_offset);
354
355 // disabled by reason
356 #if 0
357 #ifdef CACHE
358 if (bitmap_offset != s->last_bitmap)
359 {
360 lseek(s->fd, bitmap_offset, SEEK_SET);
361
362 s->last_bitmap = bitmap_offset;
363
364 // Scary! Bitmap is stored as big endian 32bit entries,
365 // while we used to look it up byte by byte
366 read(s->fd, s->pageentry_u8, 512);
367 for (i = 0; i < 128; i++)
368 be32_to_cpus(&s->pageentry_u32[i]);
369 }
370
371 if ((s->pageentry_u8[pageentry_index / 8] >> (pageentry_index % 8)) & 1)
372 return -1;
373 #else
374 lseek(s->fd, bitmap_offset + (pageentry_index / 8), SEEK_SET);
375
376 read(s->fd, &bitmap_entry, 1);
377
378 if ((bitmap_entry >> (pageentry_index % 8)) & 1)
379 return -1; // not allocated
380 #endif
381 #endif
382
383 return block_offset;
384 }
385
386 /*
387 * Writes the footer to the end of the image file. This is needed when the
388 * file grows as it overwrites the old footer
389 *
390 * Returns 0 on success and < 0 on error
391 */
392 static int rewrite_footer(BlockDriverState* bs)
393 {
394 int ret;
395 BDRVVPCState *s = bs->opaque;
396 int64_t offset = s->free_data_block_offset;
397
398 ret = bdrv_pwrite_sync(bs->file, offset, s->footer_buf, HEADER_SIZE);
399 if (ret < 0)
400 return ret;
401
402 return 0;
403 }
404
405 /*
406 * Allocates a new block. This involves writing a new footer and updating
407 * the Block Allocation Table to use the space at the old end of the image
408 * file (overwriting the old footer)
409 *
410 * Returns the sectors' offset in the image file on success and < 0 on error
411 */
412 static int64_t alloc_block(BlockDriverState* bs, int64_t sector_num)
413 {
414 BDRVVPCState *s = bs->opaque;
415 int64_t bat_offset;
416 uint32_t index, bat_value;
417 int ret;
418 uint8_t bitmap[s->bitmap_size];
419
420 // Check if sector_num is valid
421 if ((sector_num < 0) || (sector_num > bs->total_sectors))
422 return -1;
423
424 // Write entry into in-memory BAT
425 index = (sector_num * 512) / s->block_size;
426 if (s->pagetable[index] != 0xFFFFFFFF)
427 return -1;
428
429 s->pagetable[index] = s->free_data_block_offset / 512;
430
431 // Initialize the block's bitmap
432 memset(bitmap, 0xff, s->bitmap_size);
433 ret = bdrv_pwrite_sync(bs->file, s->free_data_block_offset, bitmap,
434 s->bitmap_size);
435 if (ret < 0) {
436 return ret;
437 }
438
439 // Write new footer (the old one will be overwritten)
440 s->free_data_block_offset += s->block_size + s->bitmap_size;
441 ret = rewrite_footer(bs);
442 if (ret < 0)
443 goto fail;
444
445 // Write BAT entry to disk
446 bat_offset = s->bat_offset + (4 * index);
447 bat_value = be32_to_cpu(s->pagetable[index]);
448 ret = bdrv_pwrite_sync(bs->file, bat_offset, &bat_value, 4);
449 if (ret < 0)
450 goto fail;
451
452 return get_sector_offset(bs, sector_num, 0);
453
454 fail:
455 s->free_data_block_offset -= (s->block_size + s->bitmap_size);
456 return -1;
457 }
458
459 static int vpc_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
460 {
461 BDRVVPCState *s = (BDRVVPCState *)bs->opaque;
462 VHDFooter *footer = (VHDFooter *) s->footer_buf;
463
464 if (cpu_to_be32(footer->type) != VHD_FIXED) {
465 bdi->cluster_size = s->block_size;
466 }
467
468 bdi->unallocated_blocks_are_zero = true;
469 return 0;
470 }
471
472 static int vpc_read(BlockDriverState *bs, int64_t sector_num,
473 uint8_t *buf, int nb_sectors)
474 {
475 BDRVVPCState *s = bs->opaque;
476 int ret;
477 int64_t offset;
478 int64_t sectors, sectors_per_block;
479 VHDFooter *footer = (VHDFooter *) s->footer_buf;
480
481 if (cpu_to_be32(footer->type) == VHD_FIXED) {
482 return bdrv_read(bs->file, sector_num, buf, nb_sectors);
483 }
484 while (nb_sectors > 0) {
485 offset = get_sector_offset(bs, sector_num, 0);
486
487 sectors_per_block = s->block_size >> BDRV_SECTOR_BITS;
488 sectors = sectors_per_block - (sector_num % sectors_per_block);
489 if (sectors > nb_sectors) {
490 sectors = nb_sectors;
491 }
492
493 if (offset == -1) {
494 memset(buf, 0, sectors * BDRV_SECTOR_SIZE);
495 } else {
496 ret = bdrv_pread(bs->file, offset, buf,
497 sectors * BDRV_SECTOR_SIZE);
498 if (ret != sectors * BDRV_SECTOR_SIZE) {
499 return -1;
500 }
501 }
502
503 nb_sectors -= sectors;
504 sector_num += sectors;
505 buf += sectors * BDRV_SECTOR_SIZE;
506 }
507 return 0;
508 }
509
510 static coroutine_fn int vpc_co_read(BlockDriverState *bs, int64_t sector_num,
511 uint8_t *buf, int nb_sectors)
512 {
513 int ret;
514 BDRVVPCState *s = bs->opaque;
515 qemu_co_mutex_lock(&s->lock);
516 ret = vpc_read(bs, sector_num, buf, nb_sectors);
517 qemu_co_mutex_unlock(&s->lock);
518 return ret;
519 }
520
521 static int vpc_write(BlockDriverState *bs, int64_t sector_num,
522 const uint8_t *buf, int nb_sectors)
523 {
524 BDRVVPCState *s = bs->opaque;
525 int64_t offset;
526 int64_t sectors, sectors_per_block;
527 int ret;
528 VHDFooter *footer = (VHDFooter *) s->footer_buf;
529
530 if (cpu_to_be32(footer->type) == VHD_FIXED) {
531 return bdrv_write(bs->file, sector_num, buf, nb_sectors);
532 }
533 while (nb_sectors > 0) {
534 offset = get_sector_offset(bs, sector_num, 1);
535
536 sectors_per_block = s->block_size >> BDRV_SECTOR_BITS;
537 sectors = sectors_per_block - (sector_num % sectors_per_block);
538 if (sectors > nb_sectors) {
539 sectors = nb_sectors;
540 }
541
542 if (offset == -1) {
543 offset = alloc_block(bs, sector_num);
544 if (offset < 0)
545 return -1;
546 }
547
548 ret = bdrv_pwrite(bs->file, offset, buf, sectors * BDRV_SECTOR_SIZE);
549 if (ret != sectors * BDRV_SECTOR_SIZE) {
550 return -1;
551 }
552
553 nb_sectors -= sectors;
554 sector_num += sectors;
555 buf += sectors * BDRV_SECTOR_SIZE;
556 }
557
558 return 0;
559 }
560
561 static coroutine_fn int vpc_co_write(BlockDriverState *bs, int64_t sector_num,
562 const uint8_t *buf, int nb_sectors)
563 {
564 int ret;
565 BDRVVPCState *s = bs->opaque;
566 qemu_co_mutex_lock(&s->lock);
567 ret = vpc_write(bs, sector_num, buf, nb_sectors);
568 qemu_co_mutex_unlock(&s->lock);
569 return ret;
570 }
571
572 /*
573 * Calculates the number of cylinders, heads and sectors per cylinder
574 * based on a given number of sectors. This is the algorithm described
575 * in the VHD specification.
576 *
577 * Note that the geometry doesn't always exactly match total_sectors but
578 * may round it down.
579 *
580 * Returns 0 on success, -EFBIG if the size is larger than ~2 TB. Override
581 * the hardware EIDE and ATA-2 limit of 16 heads (max disk size of 127 GB)
582 * and instead allow up to 255 heads.
583 */
584 static int calculate_geometry(int64_t total_sectors, uint16_t* cyls,
585 uint8_t* heads, uint8_t* secs_per_cyl)
586 {
587 uint32_t cyls_times_heads;
588
589 /* Allow a maximum disk size of approximately 2 TB */
590 if (total_sectors > 65535LL * 255 * 255) {
591 return -EFBIG;
592 }
593
594 if (total_sectors > 65535 * 16 * 63) {
595 *secs_per_cyl = 255;
596 if (total_sectors > 65535 * 16 * 255) {
597 *heads = 255;
598 } else {
599 *heads = 16;
600 }
601 cyls_times_heads = total_sectors / *secs_per_cyl;
602 } else {
603 *secs_per_cyl = 17;
604 cyls_times_heads = total_sectors / *secs_per_cyl;
605 *heads = (cyls_times_heads + 1023) / 1024;
606
607 if (*heads < 4)
608 *heads = 4;
609
610 if (cyls_times_heads >= (*heads * 1024) || *heads > 16) {
611 *secs_per_cyl = 31;
612 *heads = 16;
613 cyls_times_heads = total_sectors / *secs_per_cyl;
614 }
615
616 if (cyls_times_heads >= (*heads * 1024)) {
617 *secs_per_cyl = 63;
618 *heads = 16;
619 cyls_times_heads = total_sectors / *secs_per_cyl;
620 }
621 }
622
623 *cyls = cyls_times_heads / *heads;
624
625 return 0;
626 }
627
628 static int create_dynamic_disk(int fd, uint8_t *buf, int64_t total_sectors)
629 {
630 VHDDynDiskHeader *dyndisk_header =
631 (VHDDynDiskHeader *) buf;
632 size_t block_size, num_bat_entries;
633 int i;
634 int ret = -EIO;
635
636 // Write the footer (twice: at the beginning and at the end)
637 block_size = 0x200000;
638 num_bat_entries = (total_sectors + block_size / 512) / (block_size / 512);
639
640 if (write(fd, buf, HEADER_SIZE) != HEADER_SIZE) {
641 goto fail;
642 }
643
644 if (lseek(fd, 1536 + ((num_bat_entries * 4 + 511) & ~511), SEEK_SET) < 0) {
645 goto fail;
646 }
647 if (write(fd, buf, HEADER_SIZE) != HEADER_SIZE) {
648 goto fail;
649 }
650
651 // Write the initial BAT
652 if (lseek(fd, 3 * 512, SEEK_SET) < 0) {
653 goto fail;
654 }
655
656 memset(buf, 0xFF, 512);
657 for (i = 0; i < (num_bat_entries * 4 + 511) / 512; i++) {
658 if (write(fd, buf, 512) != 512) {
659 goto fail;
660 }
661 }
662
663 // Prepare the Dynamic Disk Header
664 memset(buf, 0, 1024);
665
666 memcpy(dyndisk_header->magic, "cxsparse", 8);
667
668 /*
669 * Note: The spec is actually wrong here for data_offset, it says
670 * 0xFFFFFFFF, but MS tools expect all 64 bits to be set.
671 */
672 dyndisk_header->data_offset = be64_to_cpu(0xFFFFFFFFFFFFFFFFULL);
673 dyndisk_header->table_offset = be64_to_cpu(3 * 512);
674 dyndisk_header->version = be32_to_cpu(0x00010000);
675 dyndisk_header->block_size = be32_to_cpu(block_size);
676 dyndisk_header->max_table_entries = be32_to_cpu(num_bat_entries);
677
678 dyndisk_header->checksum = be32_to_cpu(vpc_checksum(buf, 1024));
679
680 // Write the header
681 if (lseek(fd, 512, SEEK_SET) < 0) {
682 goto fail;
683 }
684
685 if (write(fd, buf, 1024) != 1024) {
686 goto fail;
687 }
688 ret = 0;
689
690 fail:
691 return ret;
692 }
693
694 static int create_fixed_disk(int fd, uint8_t *buf, int64_t total_size)
695 {
696 int ret = -EIO;
697
698 /* Add footer to total size */
699 total_size += 512;
700 if (ftruncate(fd, total_size) != 0) {
701 ret = -errno;
702 goto fail;
703 }
704 if (lseek(fd, -512, SEEK_END) < 0) {
705 goto fail;
706 }
707 if (write(fd, buf, HEADER_SIZE) != HEADER_SIZE) {
708 goto fail;
709 }
710
711 ret = 0;
712
713 fail:
714 return ret;
715 }
716
717 static int vpc_create(const char *filename, QEMUOptionParameter *options,
718 Error **errp)
719 {
720 uint8_t buf[1024];
721 VHDFooter *footer = (VHDFooter *) buf;
722 QEMUOptionParameter *disk_type_param;
723 int fd, i;
724 uint16_t cyls = 0;
725 uint8_t heads = 0;
726 uint8_t secs_per_cyl = 0;
727 int64_t total_sectors;
728 int64_t total_size;
729 int disk_type;
730 int ret = -EIO;
731
732 /* Read out options */
733 total_size = get_option_parameter(options, BLOCK_OPT_SIZE)->value.n;
734
735 disk_type_param = get_option_parameter(options, BLOCK_OPT_SUBFMT);
736 if (disk_type_param && disk_type_param->value.s) {
737 if (!strcmp(disk_type_param->value.s, "dynamic")) {
738 disk_type = VHD_DYNAMIC;
739 } else if (!strcmp(disk_type_param->value.s, "fixed")) {
740 disk_type = VHD_FIXED;
741 } else {
742 return -EINVAL;
743 }
744 } else {
745 disk_type = VHD_DYNAMIC;
746 }
747
748 /* Create the file */
749 fd = qemu_open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, 0644);
750 if (fd < 0) {
751 return -EIO;
752 }
753
754 /*
755 * Calculate matching total_size and geometry. Increase the number of
756 * sectors requested until we get enough (or fail). This ensures that
757 * qemu-img convert doesn't truncate images, but rather rounds up.
758 */
759 total_sectors = total_size / BDRV_SECTOR_SIZE;
760 for (i = 0; total_sectors > (int64_t)cyls * heads * secs_per_cyl; i++) {
761 if (calculate_geometry(total_sectors + i, &cyls, &heads,
762 &secs_per_cyl))
763 {
764 ret = -EFBIG;
765 goto fail;
766 }
767 }
768
769 total_sectors = (int64_t) cyls * heads * secs_per_cyl;
770
771 /* Prepare the Hard Disk Footer */
772 memset(buf, 0, 1024);
773
774 memcpy(footer->creator, "conectix", 8);
775 /* TODO Check if "qemu" creator_app is ok for VPC */
776 memcpy(footer->creator_app, "qemu", 4);
777 memcpy(footer->creator_os, "Wi2k", 4);
778
779 footer->features = be32_to_cpu(0x02);
780 footer->version = be32_to_cpu(0x00010000);
781 if (disk_type == VHD_DYNAMIC) {
782 footer->data_offset = be64_to_cpu(HEADER_SIZE);
783 } else {
784 footer->data_offset = be64_to_cpu(0xFFFFFFFFFFFFFFFFULL);
785 }
786 footer->timestamp = be32_to_cpu(time(NULL) - VHD_TIMESTAMP_BASE);
787
788 /* Version of Virtual PC 2007 */
789 footer->major = be16_to_cpu(0x0005);
790 footer->minor = be16_to_cpu(0x0003);
791 if (disk_type == VHD_DYNAMIC) {
792 footer->orig_size = be64_to_cpu(total_sectors * 512);
793 footer->size = be64_to_cpu(total_sectors * 512);
794 } else {
795 footer->orig_size = be64_to_cpu(total_size);
796 footer->size = be64_to_cpu(total_size);
797 }
798 footer->cyls = be16_to_cpu(cyls);
799 footer->heads = heads;
800 footer->secs_per_cyl = secs_per_cyl;
801
802 footer->type = be32_to_cpu(disk_type);
803
804 #if defined(CONFIG_UUID)
805 uuid_generate(footer->uuid);
806 #endif
807
808 footer->checksum = be32_to_cpu(vpc_checksum(buf, HEADER_SIZE));
809
810 if (disk_type == VHD_DYNAMIC) {
811 ret = create_dynamic_disk(fd, buf, total_sectors);
812 } else {
813 ret = create_fixed_disk(fd, buf, total_size);
814 }
815
816 fail:
817 qemu_close(fd);
818 return ret;
819 }
820
821 static int vpc_has_zero_init(BlockDriverState *bs)
822 {
823 BDRVVPCState *s = bs->opaque;
824 VHDFooter *footer = (VHDFooter *) s->footer_buf;
825
826 if (cpu_to_be32(footer->type) == VHD_FIXED) {
827 return bdrv_has_zero_init(bs->file);
828 } else {
829 return 1;
830 }
831 }
832
833 static void vpc_close(BlockDriverState *bs)
834 {
835 BDRVVPCState *s = bs->opaque;
836 g_free(s->pagetable);
837 #ifdef CACHE
838 g_free(s->pageentry_u8);
839 #endif
840
841 migrate_del_blocker(s->migration_blocker);
842 error_free(s->migration_blocker);
843 }
844
845 static QEMUOptionParameter vpc_create_options[] = {
846 {
847 .name = BLOCK_OPT_SIZE,
848 .type = OPT_SIZE,
849 .help = "Virtual disk size"
850 },
851 {
852 .name = BLOCK_OPT_SUBFMT,
853 .type = OPT_STRING,
854 .help =
855 "Type of virtual hard disk format. Supported formats are "
856 "{dynamic (default) | fixed} "
857 },
858 { NULL }
859 };
860
861 static BlockDriver bdrv_vpc = {
862 .format_name = "vpc",
863 .instance_size = sizeof(BDRVVPCState),
864
865 .bdrv_probe = vpc_probe,
866 .bdrv_open = vpc_open,
867 .bdrv_close = vpc_close,
868 .bdrv_reopen_prepare = vpc_reopen_prepare,
869 .bdrv_create = vpc_create,
870
871 .bdrv_read = vpc_co_read,
872 .bdrv_write = vpc_co_write,
873
874 .bdrv_get_info = vpc_get_info,
875
876 .create_options = vpc_create_options,
877 .bdrv_has_zero_init = vpc_has_zero_init,
878 };
879
880 static void bdrv_vpc_init(void)
881 {
882 bdrv_register(&bdrv_vpc);
883 }
884
885 block_init(bdrv_vpc_init);