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20#include "qemu/osdep.h"
21#include "qapi/error.h"
22#include "qemu-common.h"
23#include "block/block_int.h"
24#include "qemu/error-report.h"
25#include "qemu/module.h"
26#include "qemu/bswap.h"
27#include "vhdx.h"
28
29
30typedef struct VHDXLogSequence {
31 bool valid;
32 uint32_t count;
33 VHDXLogEntries log;
34 VHDXLogEntryHeader hdr;
35} VHDXLogSequence;
36
37typedef struct VHDXLogDescEntries {
38 VHDXLogEntryHeader hdr;
39 VHDXLogDescriptor desc[];
40} VHDXLogDescEntries;
41
42static const MSGUID zero_guid = { 0 };
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57static int vhdx_log_peek_hdr(BlockDriverState *bs, VHDXLogEntries *log,
58 VHDXLogEntryHeader *hdr)
59{
60 int ret = 0;
61 uint64_t offset;
62 uint32_t read;
63
64 assert(hdr != NULL);
65
66
67 if (log->read % VHDX_LOG_SECTOR_SIZE) {
68 ret = -EFAULT;
69 goto exit;
70 }
71
72 read = log->read;
73
74
75
76 if ((read + sizeof(VHDXLogEntryHeader)) > log->length) {
77 read = 0;
78 }
79
80 if (read == log->write) {
81 ret = -EINVAL;
82 goto exit;
83 }
84
85 offset = log->offset + read;
86
87 ret = bdrv_pread(bs->file, offset, hdr, sizeof(VHDXLogEntryHeader));
88 if (ret < 0) {
89 goto exit;
90 }
91 vhdx_log_entry_hdr_le_import(hdr);
92
93exit:
94 return ret;
95}
96
97
98static int vhdx_log_inc_idx(uint32_t idx, uint64_t length)
99{
100 idx += VHDX_LOG_SECTOR_SIZE;
101
102
103
104 return idx >= length ? 0 : idx;
105}
106
107
108
109static void vhdx_log_reset(BlockDriverState *bs, BDRVVHDXState *s)
110{
111 MSGUID guid = { 0 };
112 s->log.read = s->log.write = 0;
113
114
115 vhdx_update_headers(bs, s, false, &guid);
116}
117
118
119
120
121
122
123
124
125
126
127
128
129static int vhdx_log_read_sectors(BlockDriverState *bs, VHDXLogEntries *log,
130 uint32_t *sectors_read, void *buffer,
131 uint32_t num_sectors, bool peek)
132{
133 int ret = 0;
134 uint64_t offset;
135 uint32_t read;
136
137 read = log->read;
138
139 *sectors_read = 0;
140 while (num_sectors) {
141 if (read == log->write) {
142
143 break;
144 }
145 offset = log->offset + read;
146
147 ret = bdrv_pread(bs->file, offset, buffer, VHDX_LOG_SECTOR_SIZE);
148 if (ret < 0) {
149 goto exit;
150 }
151 read = vhdx_log_inc_idx(read, log->length);
152
153 *sectors_read = *sectors_read + 1;
154 num_sectors--;
155 }
156
157exit:
158 if (!peek) {
159 log->read = read;
160 }
161 return ret;
162}
163
164
165
166
167
168
169
170
171static int vhdx_log_write_sectors(BlockDriverState *bs, VHDXLogEntries *log,
172 uint32_t *sectors_written, void *buffer,
173 uint32_t num_sectors)
174{
175 int ret = 0;
176 uint64_t offset;
177 uint32_t write;
178 void *buffer_tmp;
179 BDRVVHDXState *s = bs->opaque;
180
181 ret = vhdx_user_visible_write(bs, s);
182 if (ret < 0) {
183 goto exit;
184 }
185
186 write = log->write;
187
188 buffer_tmp = buffer;
189 while (num_sectors) {
190
191 offset = log->offset + write;
192 write = vhdx_log_inc_idx(write, log->length);
193 if (write == log->read) {
194
195 break;
196 }
197 ret = bdrv_pwrite(bs->file, offset, buffer_tmp,
198 VHDX_LOG_SECTOR_SIZE);
199 if (ret < 0) {
200 goto exit;
201 }
202 buffer_tmp += VHDX_LOG_SECTOR_SIZE;
203
204 log->write = write;
205 *sectors_written = *sectors_written + 1;
206 num_sectors--;
207 }
208
209exit:
210 return ret;
211}
212
213
214
215static bool vhdx_log_hdr_is_valid(VHDXLogEntries *log, VHDXLogEntryHeader *hdr,
216 BDRVVHDXState *s)
217{
218 int valid = false;
219
220 if (hdr->signature != VHDX_LOG_SIGNATURE) {
221 goto exit;
222 }
223
224
225
226 if (log->length < hdr->entry_length) {
227 goto exit;
228 }
229
230
231 if (hdr->entry_length % (VHDX_LOG_SECTOR_SIZE)) {
232 goto exit;
233 }
234
235
236 if (hdr->sequence_number == 0) {
237 goto exit;
238 }
239
240
241
242 if (!guid_eq(hdr->log_guid, s->headers[s->curr_header]->log_guid)) {
243 goto exit;
244 }
245
246 if (hdr->descriptor_count * sizeof(VHDXLogDescriptor) > hdr->entry_length) {
247 goto exit;
248 }
249
250 valid = true;
251
252exit:
253 return valid;
254}
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272static bool vhdx_log_desc_is_valid(VHDXLogDescriptor *desc,
273 VHDXLogEntryHeader *hdr)
274{
275 bool ret = false;
276
277 if (desc->sequence_number != hdr->sequence_number) {
278 goto exit;
279 }
280 if (desc->file_offset % VHDX_LOG_SECTOR_SIZE) {
281 goto exit;
282 }
283
284 if (desc->signature == VHDX_LOG_ZERO_SIGNATURE) {
285 if (desc->zero_length % VHDX_LOG_SECTOR_SIZE == 0) {
286
287 ret = true;
288 }
289 } else if (desc->signature == VHDX_LOG_DESC_SIGNATURE) {
290
291 ret = true;
292 }
293
294exit:
295 return ret;
296}
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317static int vhdx_compute_desc_sectors(uint32_t desc_cnt)
318{
319 uint32_t desc_sectors;
320
321 desc_cnt += 2;
322 desc_sectors = desc_cnt / 128;
323 if (desc_cnt % 128) {
324 desc_sectors++;
325 }
326
327 return desc_sectors;
328}
329
330
331
332
333
334
335static int vhdx_log_read_desc(BlockDriverState *bs, BDRVVHDXState *s,
336 VHDXLogEntries *log, VHDXLogDescEntries **buffer,
337 bool convert_endian)
338{
339 int ret = 0;
340 uint32_t desc_sectors;
341 uint32_t sectors_read;
342 VHDXLogEntryHeader hdr;
343 VHDXLogDescEntries *desc_entries = NULL;
344 VHDXLogDescriptor desc;
345 int i;
346
347 assert(*buffer == NULL);
348
349 ret = vhdx_log_peek_hdr(bs, log, &hdr);
350 if (ret < 0) {
351 goto exit;
352 }
353
354 if (vhdx_log_hdr_is_valid(log, &hdr, s) == false) {
355 ret = -EINVAL;
356 goto exit;
357 }
358
359 desc_sectors = vhdx_compute_desc_sectors(hdr.descriptor_count);
360 desc_entries = qemu_try_blockalign(bs->file->bs,
361 desc_sectors * VHDX_LOG_SECTOR_SIZE);
362 if (desc_entries == NULL) {
363 ret = -ENOMEM;
364 goto exit;
365 }
366
367 ret = vhdx_log_read_sectors(bs, log, §ors_read, desc_entries,
368 desc_sectors, false);
369 if (ret < 0) {
370 goto free_and_exit;
371 }
372 if (sectors_read != desc_sectors) {
373 ret = -EINVAL;
374 goto free_and_exit;
375 }
376
377
378 for (i = 0; i < hdr.descriptor_count; i++) {
379 desc = desc_entries->desc[i];
380 vhdx_log_desc_le_import(&desc);
381 if (convert_endian) {
382 desc_entries->desc[i] = desc;
383 }
384 if (vhdx_log_desc_is_valid(&desc, &hdr) == false) {
385 ret = -EINVAL;
386 goto free_and_exit;
387 }
388 }
389 if (convert_endian) {
390 desc_entries->hdr = hdr;
391 }
392
393 *buffer = desc_entries;
394 goto exit;
395
396free_and_exit:
397 qemu_vfree(desc_entries);
398exit:
399 return ret;
400}
401
402
403
404
405
406
407
408
409
410
411
412
413
414static int vhdx_log_flush_desc(BlockDriverState *bs, VHDXLogDescriptor *desc,
415 VHDXLogDataSector *data)
416{
417 int ret = 0;
418 uint64_t seq, file_offset;
419 uint32_t offset = 0;
420 void *buffer = NULL;
421 uint64_t count = 1;
422 int i;
423
424 buffer = qemu_blockalign(bs, VHDX_LOG_SECTOR_SIZE);
425
426 if (desc->signature == VHDX_LOG_DESC_SIGNATURE) {
427
428 if (data == NULL) {
429 ret = -EFAULT;
430 goto exit;
431 }
432
433
434
435 seq = data->sequence_high;
436 seq <<= 32;
437 seq |= data->sequence_low & 0xffffffff;
438
439 if (seq != desc->sequence_number) {
440 ret = -EINVAL;
441 goto exit;
442 }
443
444
445
446 memcpy(buffer, &desc->leading_bytes, 8);
447 offset += 8;
448
449 memcpy(buffer+offset, data->data, 4084);
450 offset += 4084;
451
452 memcpy(buffer+offset, &desc->trailing_bytes, 4);
453
454 } else if (desc->signature == VHDX_LOG_ZERO_SIGNATURE) {
455
456 memset(buffer, 0, VHDX_LOG_SECTOR_SIZE);
457 count = desc->zero_length / VHDX_LOG_SECTOR_SIZE;
458 } else {
459 error_report("Invalid VHDX log descriptor entry signature 0x%" PRIx32,
460 desc->signature);
461 ret = -EINVAL;
462 goto exit;
463 }
464
465 file_offset = desc->file_offset;
466
467
468 for (i = 0; i < count; i++) {
469 ret = bdrv_pwrite_sync(bs->file, file_offset, buffer,
470 VHDX_LOG_SECTOR_SIZE);
471 if (ret < 0) {
472 goto exit;
473 }
474 file_offset += VHDX_LOG_SECTOR_SIZE;
475 }
476
477exit:
478 qemu_vfree(buffer);
479 return ret;
480}
481
482
483
484
485
486static int vhdx_log_flush(BlockDriverState *bs, BDRVVHDXState *s,
487 VHDXLogSequence *logs)
488{
489 int ret = 0;
490 int i;
491 uint32_t cnt, sectors_read;
492 uint64_t new_file_size;
493 void *data = NULL;
494 int64_t file_length;
495 VHDXLogDescEntries *desc_entries = NULL;
496 VHDXLogEntryHeader hdr_tmp = { 0 };
497
498 cnt = logs->count;
499
500 data = qemu_blockalign(bs, VHDX_LOG_SECTOR_SIZE);
501
502 ret = vhdx_user_visible_write(bs, s);
503 if (ret < 0) {
504 goto exit;
505 }
506
507
508
509 while (cnt--) {
510 ret = vhdx_log_peek_hdr(bs, &logs->log, &hdr_tmp);
511 if (ret < 0) {
512 goto exit;
513 }
514 file_length = bdrv_getlength(bs->file->bs);
515 if (file_length < 0) {
516 ret = file_length;
517 goto exit;
518 }
519
520
521
522 if (hdr_tmp.flushed_file_offset > file_length) {
523 ret = -EINVAL;
524 goto exit;
525 }
526
527 ret = vhdx_log_read_desc(bs, s, &logs->log, &desc_entries, true);
528 if (ret < 0) {
529 goto exit;
530 }
531
532 for (i = 0; i < desc_entries->hdr.descriptor_count; i++) {
533 if (desc_entries->desc[i].signature == VHDX_LOG_DESC_SIGNATURE) {
534
535 ret = vhdx_log_read_sectors(bs, &logs->log, §ors_read,
536 data, 1, false);
537 if (ret < 0) {
538 goto exit;
539 }
540 if (sectors_read != 1) {
541 ret = -EINVAL;
542 goto exit;
543 }
544 vhdx_log_data_le_import(data);
545 }
546
547 ret = vhdx_log_flush_desc(bs, &desc_entries->desc[i], data);
548 if (ret < 0) {
549 goto exit;
550 }
551 }
552 if (file_length < desc_entries->hdr.last_file_offset) {
553 new_file_size = desc_entries->hdr.last_file_offset;
554 if (new_file_size % (1024*1024)) {
555
556 new_file_size = QEMU_ALIGN_UP(new_file_size, MiB);
557 if (new_file_size > INT64_MAX) {
558 ret = -EINVAL;
559 goto exit;
560 }
561 ret = bdrv_truncate(bs->file, new_file_size, PREALLOC_MODE_OFF,
562 NULL);
563 if (ret < 0) {
564 goto exit;
565 }
566 }
567 }
568 qemu_vfree(desc_entries);
569 desc_entries = NULL;
570 }
571
572 ret = bdrv_flush(bs);
573 if (ret < 0) {
574 goto exit;
575 }
576
577
578 vhdx_log_reset(bs, s);
579
580exit:
581 qemu_vfree(data);
582 qemu_vfree(desc_entries);
583 return ret;
584}
585
586static int vhdx_validate_log_entry(BlockDriverState *bs, BDRVVHDXState *s,
587 VHDXLogEntries *log, uint64_t seq,
588 bool *valid, VHDXLogEntryHeader *entry)
589{
590 int ret = 0;
591 VHDXLogEntryHeader hdr;
592 void *buffer = NULL;
593 uint32_t i, desc_sectors, total_sectors, crc;
594 uint32_t sectors_read = 0;
595 VHDXLogDescEntries *desc_buffer = NULL;
596
597 *valid = false;
598
599 ret = vhdx_log_peek_hdr(bs, log, &hdr);
600 if (ret < 0) {
601 goto inc_and_exit;
602 }
603
604 if (vhdx_log_hdr_is_valid(log, &hdr, s) == false) {
605 goto inc_and_exit;
606 }
607
608 if (seq > 0) {
609 if (hdr.sequence_number != seq + 1) {
610 goto inc_and_exit;
611 }
612 }
613
614 desc_sectors = vhdx_compute_desc_sectors(hdr.descriptor_count);
615
616
617
618 total_sectors = hdr.entry_length / VHDX_LOG_SECTOR_SIZE;
619
620
621
622 ret = vhdx_log_read_desc(bs, s, log, &desc_buffer, false);
623 if (ret < 0) {
624 goto free_and_exit;
625 }
626
627 crc = vhdx_checksum_calc(0xffffffff, (void *)desc_buffer,
628 desc_sectors * VHDX_LOG_SECTOR_SIZE, 4);
629 crc ^= 0xffffffff;
630
631 buffer = qemu_blockalign(bs, VHDX_LOG_SECTOR_SIZE);
632 if (total_sectors > desc_sectors) {
633 for (i = 0; i < total_sectors - desc_sectors; i++) {
634 sectors_read = 0;
635 ret = vhdx_log_read_sectors(bs, log, §ors_read, buffer,
636 1, false);
637 if (ret < 0 || sectors_read != 1) {
638 goto free_and_exit;
639 }
640 crc = vhdx_checksum_calc(crc, buffer, VHDX_LOG_SECTOR_SIZE, -1);
641 crc ^= 0xffffffff;
642 }
643 }
644 crc ^= 0xffffffff;
645 if (crc != hdr.checksum) {
646 goto free_and_exit;
647 }
648
649 *valid = true;
650 *entry = hdr;
651 goto free_and_exit;
652
653inc_and_exit:
654 log->read = vhdx_log_inc_idx(log->read, log->length);
655
656free_and_exit:
657 qemu_vfree(buffer);
658 qemu_vfree(desc_buffer);
659 return ret;
660}
661
662
663
664
665static int vhdx_log_search(BlockDriverState *bs, BDRVVHDXState *s,
666 VHDXLogSequence *logs)
667{
668 int ret = 0;
669 uint32_t tail;
670 bool seq_valid = false;
671 VHDXLogSequence candidate = { 0 };
672 VHDXLogEntryHeader hdr = { 0 };
673 VHDXLogEntries curr_log;
674
675 memcpy(&curr_log, &s->log, sizeof(VHDXLogEntries));
676 curr_log.write = curr_log.length;
677 curr_log.read = 0;
678
679
680
681
682
683 for (;;) {
684 uint64_t curr_seq = 0;
685 VHDXLogSequence current = { 0 };
686
687 tail = curr_log.read;
688
689 ret = vhdx_validate_log_entry(bs, s, &curr_log, curr_seq,
690 &seq_valid, &hdr);
691 if (ret < 0) {
692 goto exit;
693 }
694
695 if (seq_valid) {
696 current.valid = true;
697 current.log = curr_log;
698 current.log.read = tail;
699 current.log.write = curr_log.read;
700 current.count = 1;
701 current.hdr = hdr;
702
703
704 for (;;) {
705 ret = vhdx_validate_log_entry(bs, s, &curr_log, curr_seq,
706 &seq_valid, &hdr);
707 if (ret < 0) {
708 goto exit;
709 }
710 if (seq_valid == false) {
711 break;
712 }
713 current.log.write = curr_log.read;
714 current.count++;
715
716 curr_seq = hdr.sequence_number;
717 }
718 }
719
720 if (current.valid) {
721 if (candidate.valid == false ||
722 current.hdr.sequence_number > candidate.hdr.sequence_number) {
723 candidate = current;
724 }
725 }
726
727 if (curr_log.read < tail) {
728 break;
729 }
730 }
731
732 *logs = candidate;
733
734 if (candidate.valid) {
735
736 s->log.sequence = candidate.hdr.sequence_number + 1;
737 }
738
739
740exit:
741 return ret;
742}
743
744
745
746
747
748
749int vhdx_parse_log(BlockDriverState *bs, BDRVVHDXState *s, bool *flushed,
750 Error **errp)
751{
752 int ret = 0;
753 VHDXHeader *hdr;
754 VHDXLogSequence logs = { 0 };
755
756 hdr = s->headers[s->curr_header];
757
758 *flushed = false;
759
760
761 if (s->log.hdr == NULL) {
762 s->log.hdr = qemu_blockalign(bs, sizeof(VHDXLogEntryHeader));
763 }
764
765 s->log.offset = hdr->log_offset;
766 s->log.length = hdr->log_length;
767
768 if (s->log.offset < VHDX_LOG_MIN_SIZE ||
769 s->log.offset % VHDX_LOG_MIN_SIZE) {
770 ret = -EINVAL;
771 goto exit;
772 }
773
774
775 if (hdr->log_version != 0) {
776 ret = -EINVAL;
777 goto exit;
778 }
779
780
781
782 if (guid_eq(hdr->log_guid, zero_guid)) {
783 goto exit;
784 }
785
786 if (hdr->log_length == 0) {
787 goto exit;
788 }
789
790 if (hdr->log_length % VHDX_LOG_MIN_SIZE) {
791 ret = -EINVAL;
792 goto exit;
793 }
794
795
796
797
798
799 ret = vhdx_log_search(bs, s, &logs);
800 if (ret < 0) {
801 goto exit;
802 }
803
804 if (logs.valid) {
805 if (bs->read_only) {
806 ret = -EPERM;
807 error_setg(errp,
808 "VHDX image file '%s' opened read-only, but "
809 "contains a log that needs to be replayed",
810 bs->filename);
811 error_append_hint(errp, "To replay the log, run:\n"
812 "qemu-img check -r all '%s'\n",
813 bs->filename);
814 goto exit;
815 }
816
817 ret = vhdx_log_flush(bs, s, &logs);
818 if (ret < 0) {
819 goto exit;
820 }
821 *flushed = true;
822 }
823
824
825exit:
826 return ret;
827}
828
829
830
831static void vhdx_log_raw_to_le_sector(VHDXLogDescriptor *desc,
832 VHDXLogDataSector *sector, void *data,
833 uint64_t seq)
834{
835
836 memcpy(&desc->leading_bytes, data, 8);
837 data += 8;
838 desc->leading_bytes = cpu_to_le64(desc->leading_bytes);
839 memcpy(sector->data, data, 4084);
840 data += 4084;
841 memcpy(&desc->trailing_bytes, data, 4);
842 desc->trailing_bytes = cpu_to_le32(desc->trailing_bytes);
843 data += 4;
844
845 sector->sequence_high = (uint32_t) (seq >> 32);
846 sector->sequence_low = (uint32_t) (seq & 0xffffffff);
847 sector->data_signature = VHDX_LOG_DATA_SIGNATURE;
848
849 vhdx_log_desc_le_export(desc);
850 vhdx_log_data_le_export(sector);
851}
852
853
854static int vhdx_log_write(BlockDriverState *bs, BDRVVHDXState *s,
855 void *data, uint32_t length, uint64_t offset)
856{
857 int ret = 0;
858 void *buffer = NULL;
859 void *merged_sector = NULL;
860 void *data_tmp, *sector_write;
861 unsigned int i;
862 int sector_offset;
863 uint32_t desc_sectors, sectors, total_length;
864 uint32_t sectors_written = 0;
865 uint32_t aligned_length;
866 uint32_t leading_length = 0;
867 uint32_t trailing_length = 0;
868 uint32_t partial_sectors = 0;
869 uint32_t bytes_written = 0;
870 uint64_t file_offset;
871 int64_t file_length;
872 VHDXHeader *header;
873 VHDXLogEntryHeader new_hdr;
874 VHDXLogDescriptor *new_desc = NULL;
875 VHDXLogDataSector *data_sector = NULL;
876 MSGUID new_guid = { 0 };
877
878 header = s->headers[s->curr_header];
879
880
881
882 if (length > header->log_length) {
883
884 ret = -EINVAL;
885 goto exit;
886 }
887
888 if (guid_eq(header->log_guid, zero_guid)) {
889 vhdx_guid_generate(&new_guid);
890 vhdx_update_headers(bs, s, false, &new_guid);
891 } else {
892
893
894 ret = -ENOTSUP;
895 goto exit;
896 }
897
898
899
900 if (s->log.sequence == 0) {
901 s->log.sequence = 1;
902 }
903
904 sector_offset = offset % VHDX_LOG_SECTOR_SIZE;
905 file_offset = QEMU_ALIGN_DOWN(offset, VHDX_LOG_SECTOR_SIZE);
906
907 aligned_length = length;
908
909
910 if (sector_offset) {
911 leading_length = (VHDX_LOG_SECTOR_SIZE - sector_offset);
912 leading_length = leading_length > length ? length : leading_length;
913 aligned_length -= leading_length;
914 partial_sectors++;
915 }
916
917 sectors = aligned_length / VHDX_LOG_SECTOR_SIZE;
918 trailing_length = aligned_length - (sectors * VHDX_LOG_SECTOR_SIZE);
919 if (trailing_length) {
920 partial_sectors++;
921 }
922
923 sectors += partial_sectors;
924
925 file_length = bdrv_getlength(bs->file->bs);
926 if (file_length < 0) {
927 ret = file_length;
928 goto exit;
929 }
930
931
932
933
934 new_hdr = (VHDXLogEntryHeader) {
935 .signature = VHDX_LOG_SIGNATURE,
936 .tail = s->log.tail,
937 .sequence_number = s->log.sequence,
938 .descriptor_count = sectors,
939 .reserved = 0,
940 .flushed_file_offset = file_length,
941 .last_file_offset = file_length,
942 .log_guid = header->log_guid,
943 };
944
945
946 desc_sectors = vhdx_compute_desc_sectors(new_hdr.descriptor_count);
947
948 total_length = (desc_sectors + sectors) * VHDX_LOG_SECTOR_SIZE;
949 new_hdr.entry_length = total_length;
950
951 vhdx_log_entry_hdr_le_export(&new_hdr);
952
953 buffer = qemu_blockalign(bs, total_length);
954 memcpy(buffer, &new_hdr, sizeof(new_hdr));
955
956 new_desc = buffer + sizeof(new_hdr);
957 data_sector = buffer + (desc_sectors * VHDX_LOG_SECTOR_SIZE);
958 data_tmp = data;
959
960
961
962
963 merged_sector = qemu_blockalign(bs, VHDX_LOG_SECTOR_SIZE);
964
965 for (i = 0; i < sectors; i++) {
966 new_desc->signature = VHDX_LOG_DESC_SIGNATURE;
967 new_desc->sequence_number = s->log.sequence;
968 new_desc->file_offset = file_offset;
969
970 if (i == 0 && leading_length) {
971
972 ret = bdrv_pread(bs->file, file_offset, merged_sector,
973 VHDX_LOG_SECTOR_SIZE);
974 if (ret < 0) {
975 goto exit;
976 }
977 memcpy(merged_sector + sector_offset, data_tmp, leading_length);
978 bytes_written = leading_length;
979 sector_write = merged_sector;
980 } else if (i == sectors - 1 && trailing_length) {
981
982 ret = bdrv_pread(bs->file,
983 file_offset,
984 merged_sector + trailing_length,
985 VHDX_LOG_SECTOR_SIZE - trailing_length);
986 if (ret < 0) {
987 goto exit;
988 }
989 memcpy(merged_sector, data_tmp, trailing_length);
990 bytes_written = trailing_length;
991 sector_write = merged_sector;
992 } else {
993 bytes_written = VHDX_LOG_SECTOR_SIZE;
994 sector_write = data_tmp;
995 }
996
997
998
999
1000 vhdx_log_raw_to_le_sector(new_desc, data_sector, sector_write,
1001 s->log.sequence);
1002
1003 data_tmp += bytes_written;
1004 data_sector++;
1005 new_desc++;
1006 file_offset += VHDX_LOG_SECTOR_SIZE;
1007 }
1008
1009
1010
1011 vhdx_update_checksum(buffer, total_length,
1012 offsetof(VHDXLogEntryHeader, checksum));
1013
1014
1015 ret = vhdx_log_write_sectors(bs, &s->log, §ors_written, buffer,
1016 desc_sectors + sectors);
1017 if (ret < 0) {
1018 goto exit;
1019 }
1020
1021 if (sectors_written != desc_sectors + sectors) {
1022
1023 ret = -EINVAL;
1024 goto exit;
1025 }
1026
1027 s->log.sequence++;
1028
1029 s->log.tail = s->log.write;
1030
1031exit:
1032 qemu_vfree(buffer);
1033 qemu_vfree(merged_sector);
1034 return ret;
1035}
1036
1037
1038int vhdx_log_write_and_flush(BlockDriverState *bs, BDRVVHDXState *s,
1039 void *data, uint32_t length, uint64_t offset)
1040{
1041 int ret = 0;
1042 VHDXLogSequence logs = { .valid = true,
1043 .count = 1,
1044 .hdr = { 0 } };
1045
1046
1047
1048
1049 ret = bdrv_flush(bs);
1050 if (ret < 0) {
1051 goto exit;
1052 }
1053
1054 ret = vhdx_log_write(bs, s, data, length, offset);
1055 if (ret < 0) {
1056 goto exit;
1057 }
1058 logs.log = s->log;
1059
1060
1061 ret = bdrv_flush(bs);
1062 if (ret < 0) {
1063 goto exit;
1064 }
1065
1066 ret = vhdx_log_flush(bs, s, &logs);
1067 if (ret < 0) {
1068 goto exit;
1069 }
1070
1071 s->log = logs.log;
1072
1073exit:
1074 return ret;
1075}
1076
1077