xref: /qemu/block/vmdk.c (revision 336d354b)
1 /*
2  * Block driver for the VMDK format
3  *
4  * Copyright (c) 2004 Fabrice Bellard
5  * Copyright (c) 2005 Filip Navara
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 
26 #include "qemu/osdep.h"
27 #include "qapi/error.h"
28 #include "block/block_int.h"
29 #include "sysemu/block-backend.h"
30 #include "qapi/qmp/qdict.h"
31 #include "qapi/qmp/qerror.h"
32 #include "qemu/error-report.h"
33 #include "qemu/module.h"
34 #include "qemu/option.h"
35 #include "qemu/bswap.h"
36 #include "qemu/memalign.h"
37 #include "migration/blocker.h"
38 #include "qemu/cutils.h"
39 #include <zlib.h>
40 
41 #define VMDK3_MAGIC (('C' << 24) | ('O' << 16) | ('W' << 8) | 'D')
42 #define VMDK4_MAGIC (('K' << 24) | ('D' << 16) | ('M' << 8) | 'V')
43 #define VMDK4_COMPRESSION_DEFLATE 1
44 #define VMDK4_FLAG_NL_DETECT (1 << 0)
45 #define VMDK4_FLAG_RGD (1 << 1)
46 /* Zeroed-grain enable bit */
47 #define VMDK4_FLAG_ZERO_GRAIN   (1 << 2)
48 #define VMDK4_FLAG_COMPRESS (1 << 16)
49 #define VMDK4_FLAG_MARKER (1 << 17)
50 #define VMDK4_GD_AT_END 0xffffffffffffffffULL
51 
52 #define VMDK_EXTENT_MAX_SECTORS (1ULL << 32)
53 
54 #define VMDK_GTE_ZEROED 0x1
55 
56 /* VMDK internal error codes */
57 #define VMDK_OK      0
58 #define VMDK_ERROR   (-1)
59 /* Cluster not allocated */
60 #define VMDK_UNALLOC (-2)
61 #define VMDK_ZEROED  (-3)
62 
63 #define BLOCK_OPT_ZEROED_GRAIN "zeroed_grain"
64 #define BLOCK_OPT_TOOLSVERSION "toolsversion"
65 
66 typedef struct {
67     uint32_t version;
68     uint32_t flags;
69     uint32_t disk_sectors;
70     uint32_t granularity;
71     uint32_t l1dir_offset;
72     uint32_t l1dir_size;
73     uint32_t file_sectors;
74     uint32_t cylinders;
75     uint32_t heads;
76     uint32_t sectors_per_track;
77 } QEMU_PACKED VMDK3Header;
78 
79 typedef struct {
80     uint32_t version;
81     uint32_t flags;
82     uint64_t capacity;
83     uint64_t granularity;
84     uint64_t desc_offset;
85     uint64_t desc_size;
86     /* Number of GrainTableEntries per GrainTable */
87     uint32_t num_gtes_per_gt;
88     uint64_t rgd_offset;
89     uint64_t gd_offset;
90     uint64_t grain_offset;
91     char filler[1];
92     char check_bytes[4];
93     uint16_t compressAlgorithm;
94 } QEMU_PACKED VMDK4Header;
95 
96 typedef struct VMDKSESparseConstHeader {
97     uint64_t magic;
98     uint64_t version;
99     uint64_t capacity;
100     uint64_t grain_size;
101     uint64_t grain_table_size;
102     uint64_t flags;
103     uint64_t reserved1;
104     uint64_t reserved2;
105     uint64_t reserved3;
106     uint64_t reserved4;
107     uint64_t volatile_header_offset;
108     uint64_t volatile_header_size;
109     uint64_t journal_header_offset;
110     uint64_t journal_header_size;
111     uint64_t journal_offset;
112     uint64_t journal_size;
113     uint64_t grain_dir_offset;
114     uint64_t grain_dir_size;
115     uint64_t grain_tables_offset;
116     uint64_t grain_tables_size;
117     uint64_t free_bitmap_offset;
118     uint64_t free_bitmap_size;
119     uint64_t backmap_offset;
120     uint64_t backmap_size;
121     uint64_t grains_offset;
122     uint64_t grains_size;
123     uint8_t pad[304];
124 } QEMU_PACKED VMDKSESparseConstHeader;
125 
126 typedef struct VMDKSESparseVolatileHeader {
127     uint64_t magic;
128     uint64_t free_gt_number;
129     uint64_t next_txn_seq_number;
130     uint64_t replay_journal;
131     uint8_t pad[480];
132 } QEMU_PACKED VMDKSESparseVolatileHeader;
133 
134 #define L2_CACHE_SIZE 16
135 
136 typedef struct VmdkExtent {
137     BdrvChild *file;
138     bool flat;
139     bool compressed;
140     bool has_marker;
141     bool has_zero_grain;
142     bool sesparse;
143     uint64_t sesparse_l2_tables_offset;
144     uint64_t sesparse_clusters_offset;
145     int32_t entry_size;
146     int version;
147     int64_t sectors;
148     int64_t end_sector;
149     int64_t flat_start_offset;
150     int64_t l1_table_offset;
151     int64_t l1_backup_table_offset;
152     void *l1_table;
153     uint32_t *l1_backup_table;
154     unsigned int l1_size;
155     uint32_t l1_entry_sectors;
156 
157     unsigned int l2_size;
158     void *l2_cache;
159     uint32_t l2_cache_offsets[L2_CACHE_SIZE];
160     uint32_t l2_cache_counts[L2_CACHE_SIZE];
161 
162     int64_t cluster_sectors;
163     int64_t next_cluster_sector;
164     char *type;
165 } VmdkExtent;
166 
167 typedef struct BDRVVmdkState {
168     CoMutex lock;
169     uint64_t desc_offset;
170     bool cid_updated;
171     bool cid_checked;
172     uint32_t cid;
173     uint32_t parent_cid;
174     int num_extents;
175     /* Extent array with num_extents entries, ascend ordered by address */
176     VmdkExtent *extents;
177     Error *migration_blocker;
178     char *create_type;
179 } BDRVVmdkState;
180 
181 typedef struct VmdkMetaData {
182     unsigned int l1_index;
183     unsigned int l2_index;
184     unsigned int l2_offset;
185     bool new_allocation;
186     uint32_t *l2_cache_entry;
187 } VmdkMetaData;
188 
189 typedef struct VmdkGrainMarker {
190     uint64_t lba;
191     uint32_t size;
192     uint8_t  data[];
193 } QEMU_PACKED VmdkGrainMarker;
194 
195 enum {
196     MARKER_END_OF_STREAM    = 0,
197     MARKER_GRAIN_TABLE      = 1,
198     MARKER_GRAIN_DIRECTORY  = 2,
199     MARKER_FOOTER           = 3,
200 };
201 
202 static int vmdk_probe(const uint8_t *buf, int buf_size, const char *filename)
203 {
204     uint32_t magic;
205 
206     if (buf_size < 4) {
207         return 0;
208     }
209     magic = be32_to_cpu(*(uint32_t *)buf);
210     if (magic == VMDK3_MAGIC ||
211         magic == VMDK4_MAGIC) {
212         return 100;
213     } else {
214         const char *p = (const char *)buf;
215         const char *end = p + buf_size;
216         while (p < end) {
217             if (*p == '#') {
218                 /* skip comment line */
219                 while (p < end && *p != '\n') {
220                     p++;
221                 }
222                 p++;
223                 continue;
224             }
225             if (*p == ' ') {
226                 while (p < end && *p == ' ') {
227                     p++;
228                 }
229                 /* skip '\r' if windows line endings used. */
230                 if (p < end && *p == '\r') {
231                     p++;
232                 }
233                 /* only accept blank lines before 'version=' line */
234                 if (p == end || *p != '\n') {
235                     return 0;
236                 }
237                 p++;
238                 continue;
239             }
240             if (end - p >= strlen("version=X\n")) {
241                 if (strncmp("version=1\n", p, strlen("version=1\n")) == 0 ||
242                     strncmp("version=2\n", p, strlen("version=2\n")) == 0 ||
243                     strncmp("version=3\n", p, strlen("version=3\n")) == 0) {
244                     return 100;
245                 }
246             }
247             if (end - p >= strlen("version=X\r\n")) {
248                 if (strncmp("version=1\r\n", p, strlen("version=1\r\n")) == 0 ||
249                     strncmp("version=2\r\n", p, strlen("version=2\r\n")) == 0 ||
250                     strncmp("version=3\r\n", p, strlen("version=3\r\n")) == 0) {
251                     return 100;
252                 }
253             }
254             return 0;
255         }
256         return 0;
257     }
258 }
259 
260 #define SECTOR_SIZE 512
261 #define DESC_SIZE (20 * SECTOR_SIZE)    /* 20 sectors of 512 bytes each */
262 #define BUF_SIZE 4096
263 #define HEADER_SIZE 512                 /* first sector of 512 bytes */
264 
265 static void vmdk_free_extents(BlockDriverState *bs)
266 {
267     int i;
268     BDRVVmdkState *s = bs->opaque;
269     VmdkExtent *e;
270 
271     for (i = 0; i < s->num_extents; i++) {
272         e = &s->extents[i];
273         g_free(e->l1_table);
274         g_free(e->l2_cache);
275         g_free(e->l1_backup_table);
276         g_free(e->type);
277         if (e->file != bs->file) {
278             bdrv_unref_child(bs, e->file);
279         }
280     }
281     g_free(s->extents);
282 }
283 
284 static void vmdk_free_last_extent(BlockDriverState *bs)
285 {
286     BDRVVmdkState *s = bs->opaque;
287 
288     if (s->num_extents == 0) {
289         return;
290     }
291     s->num_extents--;
292     s->extents = g_renew(VmdkExtent, s->extents, s->num_extents);
293 }
294 
295 /* Return -ve errno, or 0 on success and write CID into *pcid. */
296 static int vmdk_read_cid(BlockDriverState *bs, int parent, uint32_t *pcid)
297 {
298     char *desc;
299     uint32_t cid;
300     const char *p_name, *cid_str;
301     size_t cid_str_size;
302     BDRVVmdkState *s = bs->opaque;
303     int ret;
304 
305     desc = g_malloc0(DESC_SIZE);
306     ret = bdrv_pread(bs->file, s->desc_offset, desc, DESC_SIZE);
307     if (ret < 0) {
308         goto out;
309     }
310 
311     if (parent) {
312         cid_str = "parentCID";
313         cid_str_size = sizeof("parentCID");
314     } else {
315         cid_str = "CID";
316         cid_str_size = sizeof("CID");
317     }
318 
319     desc[DESC_SIZE - 1] = '\0';
320     p_name = strstr(desc, cid_str);
321     if (p_name == NULL) {
322         ret = -EINVAL;
323         goto out;
324     }
325     p_name += cid_str_size;
326     if (sscanf(p_name, "%" SCNx32, &cid) != 1) {
327         ret = -EINVAL;
328         goto out;
329     }
330     *pcid = cid;
331     ret = 0;
332 
333 out:
334     g_free(desc);
335     return ret;
336 }
337 
338 static int vmdk_write_cid(BlockDriverState *bs, uint32_t cid)
339 {
340     char *desc, *tmp_desc;
341     char *p_name, *tmp_str;
342     BDRVVmdkState *s = bs->opaque;
343     int ret = 0;
344 
345     desc = g_malloc0(DESC_SIZE);
346     tmp_desc = g_malloc0(DESC_SIZE);
347     ret = bdrv_pread(bs->file, s->desc_offset, desc, DESC_SIZE);
348     if (ret < 0) {
349         goto out;
350     }
351 
352     desc[DESC_SIZE - 1] = '\0';
353     tmp_str = strstr(desc, "parentCID");
354     if (tmp_str == NULL) {
355         ret = -EINVAL;
356         goto out;
357     }
358 
359     pstrcpy(tmp_desc, DESC_SIZE, tmp_str);
360     p_name = strstr(desc, "CID");
361     if (p_name != NULL) {
362         p_name += sizeof("CID");
363         snprintf(p_name, DESC_SIZE - (p_name - desc), "%" PRIx32 "\n", cid);
364         pstrcat(desc, DESC_SIZE, tmp_desc);
365     }
366 
367     ret = bdrv_pwrite_sync(bs->file, s->desc_offset, desc, DESC_SIZE);
368 
369 out:
370     g_free(desc);
371     g_free(tmp_desc);
372     return ret;
373 }
374 
375 static int vmdk_is_cid_valid(BlockDriverState *bs)
376 {
377     BDRVVmdkState *s = bs->opaque;
378     uint32_t cur_pcid;
379 
380     if (!s->cid_checked && bs->backing) {
381         BlockDriverState *p_bs = bs->backing->bs;
382 
383         if (strcmp(p_bs->drv->format_name, "vmdk")) {
384             /* Backing file is not in vmdk format, so it does not have
385              * a CID, which makes the overlay's parent CID invalid */
386             return 0;
387         }
388 
389         if (vmdk_read_cid(p_bs, 0, &cur_pcid) != 0) {
390             /* read failure: report as not valid */
391             return 0;
392         }
393         if (s->parent_cid != cur_pcid) {
394             /* CID not valid */
395             return 0;
396         }
397     }
398     s->cid_checked = true;
399     /* CID valid */
400     return 1;
401 }
402 
403 /* We have nothing to do for VMDK reopen, stubs just return success */
404 static int vmdk_reopen_prepare(BDRVReopenState *state,
405                                BlockReopenQueue *queue, Error **errp)
406 {
407     assert(state != NULL);
408     assert(state->bs != NULL);
409     return 0;
410 }
411 
412 static int vmdk_parent_open(BlockDriverState *bs)
413 {
414     char *p_name;
415     char *desc;
416     BDRVVmdkState *s = bs->opaque;
417     int ret;
418 
419     desc = g_malloc0(DESC_SIZE + 1);
420     ret = bdrv_pread(bs->file, s->desc_offset, desc, DESC_SIZE);
421     if (ret < 0) {
422         goto out;
423     }
424     ret = 0;
425 
426     p_name = strstr(desc, "parentFileNameHint");
427     if (p_name != NULL) {
428         char *end_name;
429 
430         p_name += sizeof("parentFileNameHint") + 1;
431         end_name = strchr(p_name, '\"');
432         if (end_name == NULL) {
433             ret = -EINVAL;
434             goto out;
435         }
436         if ((end_name - p_name) > sizeof(bs->auto_backing_file) - 1) {
437             ret = -EINVAL;
438             goto out;
439         }
440 
441         pstrcpy(bs->auto_backing_file, end_name - p_name + 1, p_name);
442         pstrcpy(bs->backing_file, sizeof(bs->backing_file),
443                 bs->auto_backing_file);
444         pstrcpy(bs->backing_format, sizeof(bs->backing_format),
445                 "vmdk");
446     }
447 
448 out:
449     g_free(desc);
450     return ret;
451 }
452 
453 /* Create and append extent to the extent array. Return the added VmdkExtent
454  * address. return NULL if allocation failed. */
455 static int vmdk_add_extent(BlockDriverState *bs,
456                            BdrvChild *file, bool flat, int64_t sectors,
457                            int64_t l1_offset, int64_t l1_backup_offset,
458                            uint32_t l1_size,
459                            int l2_size, uint64_t cluster_sectors,
460                            VmdkExtent **new_extent,
461                            Error **errp)
462 {
463     VmdkExtent *extent;
464     BDRVVmdkState *s = bs->opaque;
465     int64_t nb_sectors;
466 
467     if (cluster_sectors > 0x200000) {
468         /* 0x200000 * 512Bytes = 1GB for one cluster is unrealistic */
469         error_setg(errp, "Invalid granularity, image may be corrupt");
470         return -EFBIG;
471     }
472     if (l1_size > 32 * 1024 * 1024) {
473         /*
474          * Although with big capacity and small l1_entry_sectors, we can get a
475          * big l1_size, we don't want unbounded value to allocate the table.
476          * Limit it to 32M, which is enough to store:
477          *     8TB  - for both VMDK3 & VMDK4 with
478          *            minimal cluster size: 512B
479          *            minimal L2 table size: 512 entries
480          *            8 TB is still more than the maximal value supported for
481          *            VMDK3 & VMDK4 which is 2TB.
482          *     64TB - for "ESXi seSparse Extent"
483          *            minimal cluster size: 512B (default is 4KB)
484          *            L2 table size: 4096 entries (const).
485          *            64TB is more than the maximal value supported for
486          *            seSparse VMDKs (which is slightly less than 64TB)
487          */
488         error_setg(errp, "L1 size too big");
489         return -EFBIG;
490     }
491 
492     nb_sectors = bdrv_nb_sectors(file->bs);
493     if (nb_sectors < 0) {
494         return nb_sectors;
495     }
496 
497     s->extents = g_renew(VmdkExtent, s->extents, s->num_extents + 1);
498     extent = &s->extents[s->num_extents];
499     s->num_extents++;
500 
501     memset(extent, 0, sizeof(VmdkExtent));
502     extent->file = file;
503     extent->flat = flat;
504     extent->sectors = sectors;
505     extent->l1_table_offset = l1_offset;
506     extent->l1_backup_table_offset = l1_backup_offset;
507     extent->l1_size = l1_size;
508     extent->l1_entry_sectors = l2_size * cluster_sectors;
509     extent->l2_size = l2_size;
510     extent->cluster_sectors = flat ? sectors : cluster_sectors;
511     extent->next_cluster_sector = ROUND_UP(nb_sectors, cluster_sectors);
512     extent->entry_size = sizeof(uint32_t);
513 
514     if (s->num_extents > 1) {
515         extent->end_sector = (*(extent - 1)).end_sector + extent->sectors;
516     } else {
517         extent->end_sector = extent->sectors;
518     }
519     bs->total_sectors = extent->end_sector;
520     if (new_extent) {
521         *new_extent = extent;
522     }
523     return 0;
524 }
525 
526 static int vmdk_init_tables(BlockDriverState *bs, VmdkExtent *extent,
527                             Error **errp)
528 {
529     int ret;
530     size_t l1_size;
531     int i;
532 
533     /* read the L1 table */
534     l1_size = extent->l1_size * extent->entry_size;
535     extent->l1_table = g_try_malloc(l1_size);
536     if (l1_size && extent->l1_table == NULL) {
537         return -ENOMEM;
538     }
539 
540     ret = bdrv_pread(extent->file,
541                      extent->l1_table_offset,
542                      extent->l1_table,
543                      l1_size);
544     if (ret < 0) {
545         bdrv_refresh_filename(extent->file->bs);
546         error_setg_errno(errp, -ret,
547                          "Could not read l1 table from extent '%s'",
548                          extent->file->bs->filename);
549         goto fail_l1;
550     }
551     for (i = 0; i < extent->l1_size; i++) {
552         if (extent->entry_size == sizeof(uint64_t)) {
553             le64_to_cpus((uint64_t *)extent->l1_table + i);
554         } else {
555             assert(extent->entry_size == sizeof(uint32_t));
556             le32_to_cpus((uint32_t *)extent->l1_table + i);
557         }
558     }
559 
560     if (extent->l1_backup_table_offset) {
561         assert(!extent->sesparse);
562         extent->l1_backup_table = g_try_malloc(l1_size);
563         if (l1_size && extent->l1_backup_table == NULL) {
564             ret = -ENOMEM;
565             goto fail_l1;
566         }
567         ret = bdrv_pread(extent->file,
568                          extent->l1_backup_table_offset,
569                          extent->l1_backup_table,
570                          l1_size);
571         if (ret < 0) {
572             bdrv_refresh_filename(extent->file->bs);
573             error_setg_errno(errp, -ret,
574                              "Could not read l1 backup table from extent '%s'",
575                              extent->file->bs->filename);
576             goto fail_l1b;
577         }
578         for (i = 0; i < extent->l1_size; i++) {
579             le32_to_cpus(&extent->l1_backup_table[i]);
580         }
581     }
582 
583     extent->l2_cache =
584         g_malloc(extent->entry_size * extent->l2_size * L2_CACHE_SIZE);
585     return 0;
586  fail_l1b:
587     g_free(extent->l1_backup_table);
588  fail_l1:
589     g_free(extent->l1_table);
590     return ret;
591 }
592 
593 static int vmdk_open_vmfs_sparse(BlockDriverState *bs,
594                                  BdrvChild *file,
595                                  int flags, Error **errp)
596 {
597     int ret;
598     uint32_t magic;
599     VMDK3Header header;
600     VmdkExtent *extent = NULL;
601 
602     ret = bdrv_pread(file, sizeof(magic), &header, sizeof(header));
603     if (ret < 0) {
604         bdrv_refresh_filename(file->bs);
605         error_setg_errno(errp, -ret,
606                          "Could not read header from file '%s'",
607                          file->bs->filename);
608         return ret;
609     }
610     ret = vmdk_add_extent(bs, file, false,
611                           le32_to_cpu(header.disk_sectors),
612                           (int64_t)le32_to_cpu(header.l1dir_offset) << 9,
613                           0,
614                           le32_to_cpu(header.l1dir_size),
615                           4096,
616                           le32_to_cpu(header.granularity),
617                           &extent,
618                           errp);
619     if (ret < 0) {
620         return ret;
621     }
622     ret = vmdk_init_tables(bs, extent, errp);
623     if (ret) {
624         /* free extent allocated by vmdk_add_extent */
625         vmdk_free_last_extent(bs);
626     }
627     return ret;
628 }
629 
630 #define SESPARSE_CONST_HEADER_MAGIC UINT64_C(0x00000000cafebabe)
631 #define SESPARSE_VOLATILE_HEADER_MAGIC UINT64_C(0x00000000cafecafe)
632 
633 /* Strict checks - format not officially documented */
634 static int check_se_sparse_const_header(VMDKSESparseConstHeader *header,
635                                         Error **errp)
636 {
637     header->magic = le64_to_cpu(header->magic);
638     header->version = le64_to_cpu(header->version);
639     header->grain_size = le64_to_cpu(header->grain_size);
640     header->grain_table_size = le64_to_cpu(header->grain_table_size);
641     header->flags = le64_to_cpu(header->flags);
642     header->reserved1 = le64_to_cpu(header->reserved1);
643     header->reserved2 = le64_to_cpu(header->reserved2);
644     header->reserved3 = le64_to_cpu(header->reserved3);
645     header->reserved4 = le64_to_cpu(header->reserved4);
646 
647     header->volatile_header_offset =
648         le64_to_cpu(header->volatile_header_offset);
649     header->volatile_header_size = le64_to_cpu(header->volatile_header_size);
650 
651     header->journal_header_offset = le64_to_cpu(header->journal_header_offset);
652     header->journal_header_size = le64_to_cpu(header->journal_header_size);
653 
654     header->journal_offset = le64_to_cpu(header->journal_offset);
655     header->journal_size = le64_to_cpu(header->journal_size);
656 
657     header->grain_dir_offset = le64_to_cpu(header->grain_dir_offset);
658     header->grain_dir_size = le64_to_cpu(header->grain_dir_size);
659 
660     header->grain_tables_offset = le64_to_cpu(header->grain_tables_offset);
661     header->grain_tables_size = le64_to_cpu(header->grain_tables_size);
662 
663     header->free_bitmap_offset = le64_to_cpu(header->free_bitmap_offset);
664     header->free_bitmap_size = le64_to_cpu(header->free_bitmap_size);
665 
666     header->backmap_offset = le64_to_cpu(header->backmap_offset);
667     header->backmap_size = le64_to_cpu(header->backmap_size);
668 
669     header->grains_offset = le64_to_cpu(header->grains_offset);
670     header->grains_size = le64_to_cpu(header->grains_size);
671 
672     if (header->magic != SESPARSE_CONST_HEADER_MAGIC) {
673         error_setg(errp, "Bad const header magic: 0x%016" PRIx64,
674                    header->magic);
675         return -EINVAL;
676     }
677 
678     if (header->version != 0x0000000200000001) {
679         error_setg(errp, "Unsupported version: 0x%016" PRIx64,
680                    header->version);
681         return -ENOTSUP;
682     }
683 
684     if (header->grain_size != 8) {
685         error_setg(errp, "Unsupported grain size: %" PRIu64,
686                    header->grain_size);
687         return -ENOTSUP;
688     }
689 
690     if (header->grain_table_size != 64) {
691         error_setg(errp, "Unsupported grain table size: %" PRIu64,
692                    header->grain_table_size);
693         return -ENOTSUP;
694     }
695 
696     if (header->flags != 0) {
697         error_setg(errp, "Unsupported flags: 0x%016" PRIx64,
698                    header->flags);
699         return -ENOTSUP;
700     }
701 
702     if (header->reserved1 != 0 || header->reserved2 != 0 ||
703         header->reserved3 != 0 || header->reserved4 != 0) {
704         error_setg(errp, "Unsupported reserved bits:"
705                    " 0x%016" PRIx64 " 0x%016" PRIx64
706                    " 0x%016" PRIx64 " 0x%016" PRIx64,
707                    header->reserved1, header->reserved2,
708                    header->reserved3, header->reserved4);
709         return -ENOTSUP;
710     }
711 
712     /* check that padding is 0 */
713     if (!buffer_is_zero(header->pad, sizeof(header->pad))) {
714         error_setg(errp, "Unsupported non-zero const header padding");
715         return -ENOTSUP;
716     }
717 
718     return 0;
719 }
720 
721 static int check_se_sparse_volatile_header(VMDKSESparseVolatileHeader *header,
722                                            Error **errp)
723 {
724     header->magic = le64_to_cpu(header->magic);
725     header->free_gt_number = le64_to_cpu(header->free_gt_number);
726     header->next_txn_seq_number = le64_to_cpu(header->next_txn_seq_number);
727     header->replay_journal = le64_to_cpu(header->replay_journal);
728 
729     if (header->magic != SESPARSE_VOLATILE_HEADER_MAGIC) {
730         error_setg(errp, "Bad volatile header magic: 0x%016" PRIx64,
731                    header->magic);
732         return -EINVAL;
733     }
734 
735     if (header->replay_journal) {
736         error_setg(errp, "Image is dirty, Replaying journal not supported");
737         return -ENOTSUP;
738     }
739 
740     /* check that padding is 0 */
741     if (!buffer_is_zero(header->pad, sizeof(header->pad))) {
742         error_setg(errp, "Unsupported non-zero volatile header padding");
743         return -ENOTSUP;
744     }
745 
746     return 0;
747 }
748 
749 static int vmdk_open_se_sparse(BlockDriverState *bs,
750                                BdrvChild *file,
751                                int flags, Error **errp)
752 {
753     int ret;
754     VMDKSESparseConstHeader const_header;
755     VMDKSESparseVolatileHeader volatile_header;
756     VmdkExtent *extent = NULL;
757 
758     ret = bdrv_apply_auto_read_only(bs,
759             "No write support for seSparse images available", errp);
760     if (ret < 0) {
761         return ret;
762     }
763 
764     assert(sizeof(const_header) == SECTOR_SIZE);
765 
766     ret = bdrv_pread(file, 0, &const_header, sizeof(const_header));
767     if (ret < 0) {
768         bdrv_refresh_filename(file->bs);
769         error_setg_errno(errp, -ret,
770                          "Could not read const header from file '%s'",
771                          file->bs->filename);
772         return ret;
773     }
774 
775     /* check const header */
776     ret = check_se_sparse_const_header(&const_header, errp);
777     if (ret < 0) {
778         return ret;
779     }
780 
781     assert(sizeof(volatile_header) == SECTOR_SIZE);
782 
783     ret = bdrv_pread(file,
784                      const_header.volatile_header_offset * SECTOR_SIZE,
785                      &volatile_header, sizeof(volatile_header));
786     if (ret < 0) {
787         bdrv_refresh_filename(file->bs);
788         error_setg_errno(errp, -ret,
789                          "Could not read volatile header from file '%s'",
790                          file->bs->filename);
791         return ret;
792     }
793 
794     /* check volatile header */
795     ret = check_se_sparse_volatile_header(&volatile_header, errp);
796     if (ret < 0) {
797         return ret;
798     }
799 
800     ret = vmdk_add_extent(bs, file, false,
801                           const_header.capacity,
802                           const_header.grain_dir_offset * SECTOR_SIZE,
803                           0,
804                           const_header.grain_dir_size *
805                           SECTOR_SIZE / sizeof(uint64_t),
806                           const_header.grain_table_size *
807                           SECTOR_SIZE / sizeof(uint64_t),
808                           const_header.grain_size,
809                           &extent,
810                           errp);
811     if (ret < 0) {
812         return ret;
813     }
814 
815     extent->sesparse = true;
816     extent->sesparse_l2_tables_offset = const_header.grain_tables_offset;
817     extent->sesparse_clusters_offset = const_header.grains_offset;
818     extent->entry_size = sizeof(uint64_t);
819 
820     ret = vmdk_init_tables(bs, extent, errp);
821     if (ret) {
822         /* free extent allocated by vmdk_add_extent */
823         vmdk_free_last_extent(bs);
824     }
825 
826     return ret;
827 }
828 
829 static int vmdk_open_desc_file(BlockDriverState *bs, int flags, char *buf,
830                                QDict *options, Error **errp);
831 
832 static char *vmdk_read_desc(BdrvChild *file, uint64_t desc_offset, Error **errp)
833 {
834     int64_t size;
835     char *buf;
836     int ret;
837 
838     size = bdrv_getlength(file->bs);
839     if (size < 0) {
840         error_setg_errno(errp, -size, "Could not access file");
841         return NULL;
842     }
843 
844     if (size < 4) {
845         /* Both descriptor file and sparse image must be much larger than 4
846          * bytes, also callers of vmdk_read_desc want to compare the first 4
847          * bytes with VMDK4_MAGIC, let's error out if less is read. */
848         error_setg(errp, "File is too small, not a valid image");
849         return NULL;
850     }
851 
852     size = MIN(size, (1 << 20) - 1);  /* avoid unbounded allocation */
853     buf = g_malloc(size + 1);
854 
855     ret = bdrv_pread(file, desc_offset, buf, size);
856     if (ret < 0) {
857         error_setg_errno(errp, -ret, "Could not read from file");
858         g_free(buf);
859         return NULL;
860     }
861     buf[ret] = 0;
862 
863     return buf;
864 }
865 
866 static int vmdk_open_vmdk4(BlockDriverState *bs,
867                            BdrvChild *file,
868                            int flags, QDict *options, Error **errp)
869 {
870     int ret;
871     uint32_t magic;
872     uint32_t l1_size, l1_entry_sectors;
873     VMDK4Header header;
874     VmdkExtent *extent = NULL;
875     BDRVVmdkState *s = bs->opaque;
876     int64_t l1_backup_offset = 0;
877     bool compressed;
878 
879     ret = bdrv_pread(file, sizeof(magic), &header, sizeof(header));
880     if (ret < 0) {
881         bdrv_refresh_filename(file->bs);
882         error_setg_errno(errp, -ret,
883                          "Could not read header from file '%s'",
884                          file->bs->filename);
885         return -EINVAL;
886     }
887     if (header.capacity == 0) {
888         uint64_t desc_offset = le64_to_cpu(header.desc_offset);
889         if (desc_offset) {
890             char *buf = vmdk_read_desc(file, desc_offset << 9, errp);
891             if (!buf) {
892                 return -EINVAL;
893             }
894             ret = vmdk_open_desc_file(bs, flags, buf, options, errp);
895             g_free(buf);
896             return ret;
897         }
898     }
899 
900     if (!s->create_type) {
901         s->create_type = g_strdup("monolithicSparse");
902     }
903 
904     if (le64_to_cpu(header.gd_offset) == VMDK4_GD_AT_END) {
905         /*
906          * The footer takes precedence over the header, so read it in. The
907          * footer starts at offset -1024 from the end: One sector for the
908          * footer, and another one for the end-of-stream marker.
909          */
910         struct {
911             struct {
912                 uint64_t val;
913                 uint32_t size;
914                 uint32_t type;
915                 uint8_t pad[512 - 16];
916             } QEMU_PACKED footer_marker;
917 
918             uint32_t magic;
919             VMDK4Header header;
920             uint8_t pad[512 - 4 - sizeof(VMDK4Header)];
921 
922             struct {
923                 uint64_t val;
924                 uint32_t size;
925                 uint32_t type;
926                 uint8_t pad[512 - 16];
927             } QEMU_PACKED eos_marker;
928         } QEMU_PACKED footer;
929 
930         ret = bdrv_pread(file,
931             bs->file->bs->total_sectors * 512 - 1536,
932             &footer, sizeof(footer));
933         if (ret < 0) {
934             error_setg_errno(errp, -ret, "Failed to read footer");
935             return ret;
936         }
937 
938         /* Some sanity checks for the footer */
939         if (be32_to_cpu(footer.magic) != VMDK4_MAGIC ||
940             le32_to_cpu(footer.footer_marker.size) != 0  ||
941             le32_to_cpu(footer.footer_marker.type) != MARKER_FOOTER ||
942             le64_to_cpu(footer.eos_marker.val) != 0  ||
943             le32_to_cpu(footer.eos_marker.size) != 0  ||
944             le32_to_cpu(footer.eos_marker.type) != MARKER_END_OF_STREAM)
945         {
946             error_setg(errp, "Invalid footer");
947             return -EINVAL;
948         }
949 
950         header = footer.header;
951     }
952 
953     compressed =
954         le16_to_cpu(header.compressAlgorithm) == VMDK4_COMPRESSION_DEFLATE;
955     if (le32_to_cpu(header.version) > 3) {
956         error_setg(errp, "Unsupported VMDK version %" PRIu32,
957                    le32_to_cpu(header.version));
958         return -ENOTSUP;
959     } else if (le32_to_cpu(header.version) == 3 && (flags & BDRV_O_RDWR) &&
960                !compressed) {
961         /* VMware KB 2064959 explains that version 3 added support for
962          * persistent changed block tracking (CBT), and backup software can
963          * read it as version=1 if it doesn't care about the changed area
964          * information. So we are safe to enable read only. */
965         error_setg(errp, "VMDK version 3 must be read only");
966         return -EINVAL;
967     }
968 
969     if (le32_to_cpu(header.num_gtes_per_gt) > 512) {
970         error_setg(errp, "L2 table size too big");
971         return -EINVAL;
972     }
973 
974     l1_entry_sectors = le32_to_cpu(header.num_gtes_per_gt)
975                         * le64_to_cpu(header.granularity);
976     if (l1_entry_sectors == 0) {
977         error_setg(errp, "L1 entry size is invalid");
978         return -EINVAL;
979     }
980     l1_size = (le64_to_cpu(header.capacity) + l1_entry_sectors - 1)
981                 / l1_entry_sectors;
982     if (le32_to_cpu(header.flags) & VMDK4_FLAG_RGD) {
983         l1_backup_offset = le64_to_cpu(header.rgd_offset) << 9;
984     }
985     if (bdrv_nb_sectors(file->bs) < le64_to_cpu(header.grain_offset)) {
986         error_setg(errp, "File truncated, expecting at least %" PRId64 " bytes",
987                    (int64_t)(le64_to_cpu(header.grain_offset)
988                              * BDRV_SECTOR_SIZE));
989         return -EINVAL;
990     }
991 
992     ret = vmdk_add_extent(bs, file, false,
993                           le64_to_cpu(header.capacity),
994                           le64_to_cpu(header.gd_offset) << 9,
995                           l1_backup_offset,
996                           l1_size,
997                           le32_to_cpu(header.num_gtes_per_gt),
998                           le64_to_cpu(header.granularity),
999                           &extent,
1000                           errp);
1001     if (ret < 0) {
1002         return ret;
1003     }
1004     extent->compressed =
1005         le16_to_cpu(header.compressAlgorithm) == VMDK4_COMPRESSION_DEFLATE;
1006     if (extent->compressed) {
1007         g_free(s->create_type);
1008         s->create_type = g_strdup("streamOptimized");
1009     }
1010     extent->has_marker = le32_to_cpu(header.flags) & VMDK4_FLAG_MARKER;
1011     extent->version = le32_to_cpu(header.version);
1012     extent->has_zero_grain = le32_to_cpu(header.flags) & VMDK4_FLAG_ZERO_GRAIN;
1013     ret = vmdk_init_tables(bs, extent, errp);
1014     if (ret) {
1015         /* free extent allocated by vmdk_add_extent */
1016         vmdk_free_last_extent(bs);
1017     }
1018     return ret;
1019 }
1020 
1021 /* find an option value out of descriptor file */
1022 static int vmdk_parse_description(const char *desc, const char *opt_name,
1023         char *buf, int buf_size)
1024 {
1025     char *opt_pos, *opt_end;
1026     const char *end = desc + strlen(desc);
1027 
1028     opt_pos = strstr(desc, opt_name);
1029     if (!opt_pos) {
1030         return VMDK_ERROR;
1031     }
1032     /* Skip "=\"" following opt_name */
1033     opt_pos += strlen(opt_name) + 2;
1034     if (opt_pos >= end) {
1035         return VMDK_ERROR;
1036     }
1037     opt_end = opt_pos;
1038     while (opt_end < end && *opt_end != '"') {
1039         opt_end++;
1040     }
1041     if (opt_end == end || buf_size < opt_end - opt_pos + 1) {
1042         return VMDK_ERROR;
1043     }
1044     pstrcpy(buf, opt_end - opt_pos + 1, opt_pos);
1045     return VMDK_OK;
1046 }
1047 
1048 /* Open an extent file and append to bs array */
1049 static int vmdk_open_sparse(BlockDriverState *bs, BdrvChild *file, int flags,
1050                             char *buf, QDict *options, Error **errp)
1051 {
1052     uint32_t magic;
1053 
1054     magic = ldl_be_p(buf);
1055     switch (magic) {
1056         case VMDK3_MAGIC:
1057             return vmdk_open_vmfs_sparse(bs, file, flags, errp);
1058         case VMDK4_MAGIC:
1059             return vmdk_open_vmdk4(bs, file, flags, options, errp);
1060         default:
1061             error_setg(errp, "Image not in VMDK format");
1062             return -EINVAL;
1063     }
1064 }
1065 
1066 static const char *next_line(const char *s)
1067 {
1068     while (*s) {
1069         if (*s == '\n') {
1070             return s + 1;
1071         }
1072         s++;
1073     }
1074     return s;
1075 }
1076 
1077 static int vmdk_parse_extents(const char *desc, BlockDriverState *bs,
1078                               QDict *options, Error **errp)
1079 {
1080     int ret;
1081     int matches;
1082     char access[11];
1083     char type[11];
1084     char fname[512];
1085     const char *p, *np;
1086     int64_t sectors = 0;
1087     int64_t flat_offset;
1088     char *desc_file_dir = NULL;
1089     char *extent_path;
1090     BdrvChild *extent_file;
1091     BdrvChildRole extent_role;
1092     BDRVVmdkState *s = bs->opaque;
1093     VmdkExtent *extent = NULL;
1094     char extent_opt_prefix[32];
1095     Error *local_err = NULL;
1096 
1097     for (p = desc; *p; p = next_line(p)) {
1098         /* parse extent line in one of below formats:
1099          *
1100          * RW [size in sectors] FLAT "file-name.vmdk" OFFSET
1101          * RW [size in sectors] SPARSE "file-name.vmdk"
1102          * RW [size in sectors] VMFS "file-name.vmdk"
1103          * RW [size in sectors] VMFSSPARSE "file-name.vmdk"
1104          * RW [size in sectors] SESPARSE "file-name.vmdk"
1105          */
1106         flat_offset = -1;
1107         matches = sscanf(p, "%10s %" SCNd64 " %10s \"%511[^\n\r\"]\" %" SCNd64,
1108                          access, &sectors, type, fname, &flat_offset);
1109         if (matches < 4 || strcmp(access, "RW")) {
1110             continue;
1111         } else if (!strcmp(type, "FLAT")) {
1112             if (matches != 5 || flat_offset < 0) {
1113                 goto invalid;
1114             }
1115         } else if (!strcmp(type, "VMFS")) {
1116             if (matches == 4) {
1117                 flat_offset = 0;
1118             } else {
1119                 goto invalid;
1120             }
1121         } else if (matches != 4) {
1122             goto invalid;
1123         }
1124 
1125         if (sectors <= 0 ||
1126             (strcmp(type, "FLAT") && strcmp(type, "SPARSE") &&
1127              strcmp(type, "VMFS") && strcmp(type, "VMFSSPARSE") &&
1128              strcmp(type, "SESPARSE")) ||
1129             (strcmp(access, "RW"))) {
1130             continue;
1131         }
1132 
1133         if (path_is_absolute(fname)) {
1134             extent_path = g_strdup(fname);
1135         } else {
1136             if (!desc_file_dir) {
1137                 desc_file_dir = bdrv_dirname(bs->file->bs, errp);
1138                 if (!desc_file_dir) {
1139                     bdrv_refresh_filename(bs->file->bs);
1140                     error_prepend(errp, "Cannot use relative paths with VMDK "
1141                                   "descriptor file '%s': ",
1142                                   bs->file->bs->filename);
1143                     ret = -EINVAL;
1144                     goto out;
1145                 }
1146             }
1147 
1148             extent_path = g_strconcat(desc_file_dir, fname, NULL);
1149         }
1150 
1151         ret = snprintf(extent_opt_prefix, 32, "extents.%d", s->num_extents);
1152         assert(ret < 32);
1153 
1154         extent_role = BDRV_CHILD_DATA;
1155         if (strcmp(type, "FLAT") != 0 && strcmp(type, "VMFS") != 0) {
1156             /* non-flat extents have metadata */
1157             extent_role |= BDRV_CHILD_METADATA;
1158         }
1159 
1160         extent_file = bdrv_open_child(extent_path, options, extent_opt_prefix,
1161                                       bs, &child_of_bds, extent_role, false,
1162                                       &local_err);
1163         g_free(extent_path);
1164         if (local_err) {
1165             error_propagate(errp, local_err);
1166             ret = -EINVAL;
1167             goto out;
1168         }
1169 
1170         /* save to extents array */
1171         if (!strcmp(type, "FLAT") || !strcmp(type, "VMFS")) {
1172             /* FLAT extent */
1173 
1174             ret = vmdk_add_extent(bs, extent_file, true, sectors,
1175                             0, 0, 0, 0, 0, &extent, errp);
1176             if (ret < 0) {
1177                 bdrv_unref_child(bs, extent_file);
1178                 goto out;
1179             }
1180             extent->flat_start_offset = flat_offset << 9;
1181         } else if (!strcmp(type, "SPARSE") || !strcmp(type, "VMFSSPARSE")) {
1182             /* SPARSE extent and VMFSSPARSE extent are both "COWD" sparse file*/
1183             char *buf = vmdk_read_desc(extent_file, 0, errp);
1184             if (!buf) {
1185                 ret = -EINVAL;
1186             } else {
1187                 ret = vmdk_open_sparse(bs, extent_file, bs->open_flags, buf,
1188                                        options, errp);
1189             }
1190             g_free(buf);
1191             if (ret) {
1192                 bdrv_unref_child(bs, extent_file);
1193                 goto out;
1194             }
1195             extent = &s->extents[s->num_extents - 1];
1196         } else if (!strcmp(type, "SESPARSE")) {
1197             ret = vmdk_open_se_sparse(bs, extent_file, bs->open_flags, errp);
1198             if (ret) {
1199                 bdrv_unref_child(bs, extent_file);
1200                 goto out;
1201             }
1202             extent = &s->extents[s->num_extents - 1];
1203         } else {
1204             error_setg(errp, "Unsupported extent type '%s'", type);
1205             bdrv_unref_child(bs, extent_file);
1206             ret = -ENOTSUP;
1207             goto out;
1208         }
1209         extent->type = g_strdup(type);
1210     }
1211 
1212     ret = 0;
1213     goto out;
1214 
1215 invalid:
1216     np = next_line(p);
1217     assert(np != p);
1218     if (np[-1] == '\n') {
1219         np--;
1220     }
1221     error_setg(errp, "Invalid extent line: %.*s", (int)(np - p), p);
1222     ret = -EINVAL;
1223 
1224 out:
1225     g_free(desc_file_dir);
1226     return ret;
1227 }
1228 
1229 static int vmdk_open_desc_file(BlockDriverState *bs, int flags, char *buf,
1230                                QDict *options, Error **errp)
1231 {
1232     int ret;
1233     char ct[128];
1234     BDRVVmdkState *s = bs->opaque;
1235 
1236     if (vmdk_parse_description(buf, "createType", ct, sizeof(ct))) {
1237         error_setg(errp, "invalid VMDK image descriptor");
1238         ret = -EINVAL;
1239         goto exit;
1240     }
1241     if (strcmp(ct, "monolithicFlat") &&
1242         strcmp(ct, "vmfs") &&
1243         strcmp(ct, "vmfsSparse") &&
1244         strcmp(ct, "seSparse") &&
1245         strcmp(ct, "twoGbMaxExtentSparse") &&
1246         strcmp(ct, "twoGbMaxExtentFlat")) {
1247         error_setg(errp, "Unsupported image type '%s'", ct);
1248         ret = -ENOTSUP;
1249         goto exit;
1250     }
1251     s->create_type = g_strdup(ct);
1252     s->desc_offset = 0;
1253     ret = vmdk_parse_extents(buf, bs, options, errp);
1254 exit:
1255     return ret;
1256 }
1257 
1258 static int vmdk_open(BlockDriverState *bs, QDict *options, int flags,
1259                      Error **errp)
1260 {
1261     char *buf;
1262     int ret;
1263     BDRVVmdkState *s = bs->opaque;
1264     uint32_t magic;
1265 
1266     bs->file = bdrv_open_child(NULL, options, "file", bs, &child_of_bds,
1267                                BDRV_CHILD_IMAGE, false, errp);
1268     if (!bs->file) {
1269         return -EINVAL;
1270     }
1271 
1272     buf = vmdk_read_desc(bs->file, 0, errp);
1273     if (!buf) {
1274         return -EINVAL;
1275     }
1276 
1277     magic = ldl_be_p(buf);
1278     switch (magic) {
1279         case VMDK3_MAGIC:
1280         case VMDK4_MAGIC:
1281             ret = vmdk_open_sparse(bs, bs->file, flags, buf, options,
1282                                    errp);
1283             s->desc_offset = 0x200;
1284             break;
1285         default:
1286             /* No data in the descriptor file */
1287             bs->file->role &= ~BDRV_CHILD_DATA;
1288 
1289             /* Must succeed because we have given up permissions if anything */
1290             bdrv_child_refresh_perms(bs, bs->file, &error_abort);
1291 
1292             ret = vmdk_open_desc_file(bs, flags, buf, options, errp);
1293             break;
1294     }
1295     if (ret) {
1296         goto fail;
1297     }
1298 
1299     /* try to open parent images, if exist */
1300     ret = vmdk_parent_open(bs);
1301     if (ret) {
1302         goto fail;
1303     }
1304     ret = vmdk_read_cid(bs, 0, &s->cid);
1305     if (ret) {
1306         goto fail;
1307     }
1308     ret = vmdk_read_cid(bs, 1, &s->parent_cid);
1309     if (ret) {
1310         goto fail;
1311     }
1312     qemu_co_mutex_init(&s->lock);
1313 
1314     /* Disable migration when VMDK images are used */
1315     error_setg(&s->migration_blocker, "The vmdk format used by node '%s' "
1316                "does not support live migration",
1317                bdrv_get_device_or_node_name(bs));
1318     ret = migrate_add_blocker(s->migration_blocker, errp);
1319     if (ret < 0) {
1320         error_free(s->migration_blocker);
1321         goto fail;
1322     }
1323 
1324     g_free(buf);
1325     return 0;
1326 
1327 fail:
1328     g_free(buf);
1329     g_free(s->create_type);
1330     s->create_type = NULL;
1331     vmdk_free_extents(bs);
1332     return ret;
1333 }
1334 
1335 
1336 static void vmdk_refresh_limits(BlockDriverState *bs, Error **errp)
1337 {
1338     BDRVVmdkState *s = bs->opaque;
1339     int i;
1340 
1341     for (i = 0; i < s->num_extents; i++) {
1342         if (!s->extents[i].flat) {
1343             bs->bl.pwrite_zeroes_alignment =
1344                 MAX(bs->bl.pwrite_zeroes_alignment,
1345                     s->extents[i].cluster_sectors << BDRV_SECTOR_BITS);
1346         }
1347     }
1348 }
1349 
1350 /**
1351  * get_whole_cluster
1352  *
1353  * Copy backing file's cluster that covers @sector_num, otherwise write zero,
1354  * to the cluster at @cluster_sector_num. If @zeroed is true, we're overwriting
1355  * a zeroed cluster in the current layer and must not copy data from the
1356  * backing file.
1357  *
1358  * If @skip_start_sector < @skip_end_sector, the relative range
1359  * [@skip_start_sector, @skip_end_sector) is not copied or written, and leave
1360  * it for call to write user data in the request.
1361  */
1362 static int get_whole_cluster(BlockDriverState *bs,
1363                              VmdkExtent *extent,
1364                              uint64_t cluster_offset,
1365                              uint64_t offset,
1366                              uint64_t skip_start_bytes,
1367                              uint64_t skip_end_bytes,
1368                              bool zeroed)
1369 {
1370     int ret = VMDK_OK;
1371     int64_t cluster_bytes;
1372     uint8_t *whole_grain;
1373     bool copy_from_backing;
1374 
1375     /* For COW, align request sector_num to cluster start */
1376     cluster_bytes = extent->cluster_sectors << BDRV_SECTOR_BITS;
1377     offset = QEMU_ALIGN_DOWN(offset, cluster_bytes);
1378     whole_grain = qemu_blockalign(bs, cluster_bytes);
1379     copy_from_backing = bs->backing && !zeroed;
1380 
1381     if (!copy_from_backing) {
1382         memset(whole_grain, 0, skip_start_bytes);
1383         memset(whole_grain + skip_end_bytes, 0, cluster_bytes - skip_end_bytes);
1384     }
1385 
1386     assert(skip_end_bytes <= cluster_bytes);
1387     /* we will be here if it's first write on non-exist grain(cluster).
1388      * try to read from parent image, if exist */
1389     if (bs->backing && !vmdk_is_cid_valid(bs)) {
1390         ret = VMDK_ERROR;
1391         goto exit;
1392     }
1393 
1394     /* Read backing data before skip range */
1395     if (skip_start_bytes > 0) {
1396         if (copy_from_backing) {
1397             /* qcow2 emits this on bs->file instead of bs->backing */
1398             BLKDBG_EVENT(extent->file, BLKDBG_COW_READ);
1399             ret = bdrv_pread(bs->backing, offset, whole_grain,
1400                              skip_start_bytes);
1401             if (ret < 0) {
1402                 ret = VMDK_ERROR;
1403                 goto exit;
1404             }
1405         }
1406         BLKDBG_EVENT(extent->file, BLKDBG_COW_WRITE);
1407         ret = bdrv_pwrite(extent->file, cluster_offset, whole_grain,
1408                           skip_start_bytes);
1409         if (ret < 0) {
1410             ret = VMDK_ERROR;
1411             goto exit;
1412         }
1413     }
1414     /* Read backing data after skip range */
1415     if (skip_end_bytes < cluster_bytes) {
1416         if (copy_from_backing) {
1417             /* qcow2 emits this on bs->file instead of bs->backing */
1418             BLKDBG_EVENT(extent->file, BLKDBG_COW_READ);
1419             ret = bdrv_pread(bs->backing, offset + skip_end_bytes,
1420                              whole_grain + skip_end_bytes,
1421                              cluster_bytes - skip_end_bytes);
1422             if (ret < 0) {
1423                 ret = VMDK_ERROR;
1424                 goto exit;
1425             }
1426         }
1427         BLKDBG_EVENT(extent->file, BLKDBG_COW_WRITE);
1428         ret = bdrv_pwrite(extent->file, cluster_offset + skip_end_bytes,
1429                           whole_grain + skip_end_bytes,
1430                           cluster_bytes - skip_end_bytes);
1431         if (ret < 0) {
1432             ret = VMDK_ERROR;
1433             goto exit;
1434         }
1435     }
1436 
1437     ret = VMDK_OK;
1438 exit:
1439     qemu_vfree(whole_grain);
1440     return ret;
1441 }
1442 
1443 static int vmdk_L2update(VmdkExtent *extent, VmdkMetaData *m_data,
1444                          uint32_t offset)
1445 {
1446     offset = cpu_to_le32(offset);
1447     /* update L2 table */
1448     BLKDBG_EVENT(extent->file, BLKDBG_L2_UPDATE);
1449     if (bdrv_pwrite(extent->file,
1450                 ((int64_t)m_data->l2_offset * 512)
1451                     + (m_data->l2_index * sizeof(offset)),
1452                 &offset, sizeof(offset)) < 0) {
1453         return VMDK_ERROR;
1454     }
1455     /* update backup L2 table */
1456     if (extent->l1_backup_table_offset != 0) {
1457         m_data->l2_offset = extent->l1_backup_table[m_data->l1_index];
1458         if (bdrv_pwrite(extent->file,
1459                     ((int64_t)m_data->l2_offset * 512)
1460                         + (m_data->l2_index * sizeof(offset)),
1461                     &offset, sizeof(offset)) < 0) {
1462             return VMDK_ERROR;
1463         }
1464     }
1465     if (bdrv_flush(extent->file->bs) < 0) {
1466         return VMDK_ERROR;
1467     }
1468     if (m_data->l2_cache_entry) {
1469         *m_data->l2_cache_entry = offset;
1470     }
1471 
1472     return VMDK_OK;
1473 }
1474 
1475 /**
1476  * get_cluster_offset
1477  *
1478  * Look up cluster offset in extent file by sector number, and store in
1479  * @cluster_offset.
1480  *
1481  * For flat extents, the start offset as parsed from the description file is
1482  * returned.
1483  *
1484  * For sparse extents, look up in L1, L2 table. If allocate is true, return an
1485  * offset for a new cluster and update L2 cache. If there is a backing file,
1486  * COW is done before returning; otherwise, zeroes are written to the allocated
1487  * cluster. Both COW and zero writing skips the sector range
1488  * [@skip_start_sector, @skip_end_sector) passed in by caller, because caller
1489  * has new data to write there.
1490  *
1491  * Returns: VMDK_OK if cluster exists and mapped in the image.
1492  *          VMDK_UNALLOC if cluster is not mapped and @allocate is false.
1493  *          VMDK_ERROR if failed.
1494  */
1495 static int get_cluster_offset(BlockDriverState *bs,
1496                               VmdkExtent *extent,
1497                               VmdkMetaData *m_data,
1498                               uint64_t offset,
1499                               bool allocate,
1500                               uint64_t *cluster_offset,
1501                               uint64_t skip_start_bytes,
1502                               uint64_t skip_end_bytes)
1503 {
1504     unsigned int l1_index, l2_offset, l2_index;
1505     int min_index, i, j;
1506     uint32_t min_count;
1507     void *l2_table;
1508     bool zeroed = false;
1509     int64_t ret;
1510     int64_t cluster_sector;
1511     unsigned int l2_size_bytes = extent->l2_size * extent->entry_size;
1512 
1513     if (m_data) {
1514         m_data->new_allocation = false;
1515     }
1516     if (extent->flat) {
1517         *cluster_offset = extent->flat_start_offset;
1518         return VMDK_OK;
1519     }
1520 
1521     offset -= (extent->end_sector - extent->sectors) * SECTOR_SIZE;
1522     l1_index = (offset >> 9) / extent->l1_entry_sectors;
1523     if (l1_index >= extent->l1_size) {
1524         return VMDK_ERROR;
1525     }
1526     if (extent->sesparse) {
1527         uint64_t l2_offset_u64;
1528 
1529         assert(extent->entry_size == sizeof(uint64_t));
1530 
1531         l2_offset_u64 = ((uint64_t *)extent->l1_table)[l1_index];
1532         if (l2_offset_u64 == 0) {
1533             l2_offset = 0;
1534         } else if ((l2_offset_u64 & 0xffffffff00000000) != 0x1000000000000000) {
1535             /*
1536              * Top most nibble is 0x1 if grain table is allocated.
1537              * strict check - top most 4 bytes must be 0x10000000 since max
1538              * supported size is 64TB for disk - so no more than 64TB / 16MB
1539              * grain directories which is smaller than uint32,
1540              * where 16MB is the only supported default grain table coverage.
1541              */
1542             return VMDK_ERROR;
1543         } else {
1544             l2_offset_u64 = l2_offset_u64 & 0x00000000ffffffff;
1545             l2_offset_u64 = extent->sesparse_l2_tables_offset +
1546                 l2_offset_u64 * l2_size_bytes / SECTOR_SIZE;
1547             if (l2_offset_u64 > 0x00000000ffffffff) {
1548                 return VMDK_ERROR;
1549             }
1550             l2_offset = (unsigned int)(l2_offset_u64);
1551         }
1552     } else {
1553         assert(extent->entry_size == sizeof(uint32_t));
1554         l2_offset = ((uint32_t *)extent->l1_table)[l1_index];
1555     }
1556     if (!l2_offset) {
1557         return VMDK_UNALLOC;
1558     }
1559     for (i = 0; i < L2_CACHE_SIZE; i++) {
1560         if (l2_offset == extent->l2_cache_offsets[i]) {
1561             /* increment the hit count */
1562             if (++extent->l2_cache_counts[i] == 0xffffffff) {
1563                 for (j = 0; j < L2_CACHE_SIZE; j++) {
1564                     extent->l2_cache_counts[j] >>= 1;
1565                 }
1566             }
1567             l2_table = (char *)extent->l2_cache + (i * l2_size_bytes);
1568             goto found;
1569         }
1570     }
1571     /* not found: load a new entry in the least used one */
1572     min_index = 0;
1573     min_count = 0xffffffff;
1574     for (i = 0; i < L2_CACHE_SIZE; i++) {
1575         if (extent->l2_cache_counts[i] < min_count) {
1576             min_count = extent->l2_cache_counts[i];
1577             min_index = i;
1578         }
1579     }
1580     l2_table = (char *)extent->l2_cache + (min_index * l2_size_bytes);
1581     BLKDBG_EVENT(extent->file, BLKDBG_L2_LOAD);
1582     if (bdrv_pread(extent->file,
1583                 (int64_t)l2_offset * 512,
1584                 l2_table,
1585                 l2_size_bytes
1586             ) != l2_size_bytes) {
1587         return VMDK_ERROR;
1588     }
1589 
1590     extent->l2_cache_offsets[min_index] = l2_offset;
1591     extent->l2_cache_counts[min_index] = 1;
1592  found:
1593     l2_index = ((offset >> 9) / extent->cluster_sectors) % extent->l2_size;
1594     if (m_data) {
1595         m_data->l1_index = l1_index;
1596         m_data->l2_index = l2_index;
1597         m_data->l2_offset = l2_offset;
1598         m_data->l2_cache_entry = ((uint32_t *)l2_table) + l2_index;
1599     }
1600 
1601     if (extent->sesparse) {
1602         cluster_sector = le64_to_cpu(((uint64_t *)l2_table)[l2_index]);
1603         switch (cluster_sector & 0xf000000000000000) {
1604         case 0x0000000000000000:
1605             /* unallocated grain */
1606             if (cluster_sector != 0) {
1607                 return VMDK_ERROR;
1608             }
1609             break;
1610         case 0x1000000000000000:
1611             /* scsi-unmapped grain - fallthrough */
1612         case 0x2000000000000000:
1613             /* zero grain */
1614             zeroed = true;
1615             break;
1616         case 0x3000000000000000:
1617             /* allocated grain */
1618             cluster_sector = (((cluster_sector & 0x0fff000000000000) >> 48) |
1619                               ((cluster_sector & 0x0000ffffffffffff) << 12));
1620             cluster_sector = extent->sesparse_clusters_offset +
1621                 cluster_sector * extent->cluster_sectors;
1622             break;
1623         default:
1624             return VMDK_ERROR;
1625         }
1626     } else {
1627         cluster_sector = le32_to_cpu(((uint32_t *)l2_table)[l2_index]);
1628 
1629         if (extent->has_zero_grain && cluster_sector == VMDK_GTE_ZEROED) {
1630             zeroed = true;
1631         }
1632     }
1633 
1634     if (!cluster_sector || zeroed) {
1635         if (!allocate) {
1636             return zeroed ? VMDK_ZEROED : VMDK_UNALLOC;
1637         }
1638         assert(!extent->sesparse);
1639 
1640         if (extent->next_cluster_sector >= VMDK_EXTENT_MAX_SECTORS) {
1641             return VMDK_ERROR;
1642         }
1643 
1644         cluster_sector = extent->next_cluster_sector;
1645         extent->next_cluster_sector += extent->cluster_sectors;
1646 
1647         /* First of all we write grain itself, to avoid race condition
1648          * that may to corrupt the image.
1649          * This problem may occur because of insufficient space on host disk
1650          * or inappropriate VM shutdown.
1651          */
1652         ret = get_whole_cluster(bs, extent, cluster_sector * BDRV_SECTOR_SIZE,
1653                                 offset, skip_start_bytes, skip_end_bytes,
1654                                 zeroed);
1655         if (ret) {
1656             return ret;
1657         }
1658         if (m_data) {
1659             m_data->new_allocation = true;
1660         }
1661     }
1662     *cluster_offset = cluster_sector << BDRV_SECTOR_BITS;
1663     return VMDK_OK;
1664 }
1665 
1666 static VmdkExtent *find_extent(BDRVVmdkState *s,
1667                                 int64_t sector_num, VmdkExtent *start_hint)
1668 {
1669     VmdkExtent *extent = start_hint;
1670 
1671     if (!extent) {
1672         extent = &s->extents[0];
1673     }
1674     while (extent < &s->extents[s->num_extents]) {
1675         if (sector_num < extent->end_sector) {
1676             return extent;
1677         }
1678         extent++;
1679     }
1680     return NULL;
1681 }
1682 
1683 static inline uint64_t vmdk_find_offset_in_cluster(VmdkExtent *extent,
1684                                                    int64_t offset)
1685 {
1686     uint64_t extent_begin_offset, extent_relative_offset;
1687     uint64_t cluster_size = extent->cluster_sectors * BDRV_SECTOR_SIZE;
1688 
1689     extent_begin_offset =
1690         (extent->end_sector - extent->sectors) * BDRV_SECTOR_SIZE;
1691     extent_relative_offset = offset - extent_begin_offset;
1692     return extent_relative_offset % cluster_size;
1693 }
1694 
1695 static int coroutine_fn vmdk_co_block_status(BlockDriverState *bs,
1696                                              bool want_zero,
1697                                              int64_t offset, int64_t bytes,
1698                                              int64_t *pnum, int64_t *map,
1699                                              BlockDriverState **file)
1700 {
1701     BDRVVmdkState *s = bs->opaque;
1702     int64_t index_in_cluster, n, ret;
1703     uint64_t cluster_offset;
1704     VmdkExtent *extent;
1705 
1706     extent = find_extent(s, offset >> BDRV_SECTOR_BITS, NULL);
1707     if (!extent) {
1708         return -EIO;
1709     }
1710     qemu_co_mutex_lock(&s->lock);
1711     ret = get_cluster_offset(bs, extent, NULL, offset, false, &cluster_offset,
1712                              0, 0);
1713     qemu_co_mutex_unlock(&s->lock);
1714 
1715     index_in_cluster = vmdk_find_offset_in_cluster(extent, offset);
1716     switch (ret) {
1717     case VMDK_ERROR:
1718         ret = -EIO;
1719         break;
1720     case VMDK_UNALLOC:
1721         ret = 0;
1722         break;
1723     case VMDK_ZEROED:
1724         ret = BDRV_BLOCK_ZERO;
1725         break;
1726     case VMDK_OK:
1727         ret = BDRV_BLOCK_DATA;
1728         if (!extent->compressed) {
1729             ret |= BDRV_BLOCK_OFFSET_VALID;
1730             *map = cluster_offset + index_in_cluster;
1731             if (extent->flat) {
1732                 ret |= BDRV_BLOCK_RECURSE;
1733             }
1734         }
1735         *file = extent->file->bs;
1736         break;
1737     }
1738 
1739     n = extent->cluster_sectors * BDRV_SECTOR_SIZE - index_in_cluster;
1740     *pnum = MIN(n, bytes);
1741     return ret;
1742 }
1743 
1744 static int vmdk_write_extent(VmdkExtent *extent, int64_t cluster_offset,
1745                             int64_t offset_in_cluster, QEMUIOVector *qiov,
1746                             uint64_t qiov_offset, uint64_t n_bytes,
1747                             uint64_t offset)
1748 {
1749     int ret;
1750     VmdkGrainMarker *data = NULL;
1751     uLongf buf_len;
1752     QEMUIOVector local_qiov;
1753     int64_t write_offset;
1754     int64_t write_end_sector;
1755 
1756     if (extent->compressed) {
1757         void *compressed_data;
1758 
1759         /* Only whole clusters */
1760         if (offset_in_cluster ||
1761             n_bytes > (extent->cluster_sectors * SECTOR_SIZE) ||
1762             (n_bytes < (extent->cluster_sectors * SECTOR_SIZE) &&
1763              offset + n_bytes != extent->end_sector * SECTOR_SIZE))
1764         {
1765             ret = -EINVAL;
1766             goto out;
1767         }
1768 
1769         if (!extent->has_marker) {
1770             ret = -EINVAL;
1771             goto out;
1772         }
1773         buf_len = (extent->cluster_sectors << 9) * 2;
1774         data = g_malloc(buf_len + sizeof(VmdkGrainMarker));
1775 
1776         compressed_data = g_malloc(n_bytes);
1777         qemu_iovec_to_buf(qiov, qiov_offset, compressed_data, n_bytes);
1778         ret = compress(data->data, &buf_len, compressed_data, n_bytes);
1779         g_free(compressed_data);
1780 
1781         if (ret != Z_OK || buf_len == 0) {
1782             ret = -EINVAL;
1783             goto out;
1784         }
1785 
1786         data->lba = cpu_to_le64(offset >> BDRV_SECTOR_BITS);
1787         data->size = cpu_to_le32(buf_len);
1788 
1789         n_bytes = buf_len + sizeof(VmdkGrainMarker);
1790         qemu_iovec_init_buf(&local_qiov, data, n_bytes);
1791 
1792         BLKDBG_EVENT(extent->file, BLKDBG_WRITE_COMPRESSED);
1793     } else {
1794         qemu_iovec_init(&local_qiov, qiov->niov);
1795         qemu_iovec_concat(&local_qiov, qiov, qiov_offset, n_bytes);
1796 
1797         BLKDBG_EVENT(extent->file, BLKDBG_WRITE_AIO);
1798     }
1799 
1800     write_offset = cluster_offset + offset_in_cluster;
1801     ret = bdrv_co_pwritev(extent->file, write_offset, n_bytes,
1802                           &local_qiov, 0);
1803 
1804     write_end_sector = DIV_ROUND_UP(write_offset + n_bytes, BDRV_SECTOR_SIZE);
1805 
1806     if (extent->compressed) {
1807         extent->next_cluster_sector = write_end_sector;
1808     } else {
1809         extent->next_cluster_sector = MAX(extent->next_cluster_sector,
1810                                           write_end_sector);
1811     }
1812 
1813     if (ret < 0) {
1814         goto out;
1815     }
1816     ret = 0;
1817  out:
1818     g_free(data);
1819     if (!extent->compressed) {
1820         qemu_iovec_destroy(&local_qiov);
1821     }
1822     return ret;
1823 }
1824 
1825 static int vmdk_read_extent(VmdkExtent *extent, int64_t cluster_offset,
1826                             int64_t offset_in_cluster, QEMUIOVector *qiov,
1827                             int bytes)
1828 {
1829     int ret;
1830     int cluster_bytes, buf_bytes;
1831     uint8_t *cluster_buf, *compressed_data;
1832     uint8_t *uncomp_buf;
1833     uint32_t data_len;
1834     VmdkGrainMarker *marker;
1835     uLongf buf_len;
1836 
1837 
1838     if (!extent->compressed) {
1839         BLKDBG_EVENT(extent->file, BLKDBG_READ_AIO);
1840         ret = bdrv_co_preadv(extent->file,
1841                              cluster_offset + offset_in_cluster, bytes,
1842                              qiov, 0);
1843         if (ret < 0) {
1844             return ret;
1845         }
1846         return 0;
1847     }
1848     cluster_bytes = extent->cluster_sectors * 512;
1849     /* Read two clusters in case GrainMarker + compressed data > one cluster */
1850     buf_bytes = cluster_bytes * 2;
1851     cluster_buf = g_malloc(buf_bytes);
1852     uncomp_buf = g_malloc(cluster_bytes);
1853     BLKDBG_EVENT(extent->file, BLKDBG_READ_COMPRESSED);
1854     ret = bdrv_pread(extent->file,
1855                 cluster_offset,
1856                 cluster_buf, buf_bytes);
1857     if (ret < 0) {
1858         goto out;
1859     }
1860     compressed_data = cluster_buf;
1861     buf_len = cluster_bytes;
1862     data_len = cluster_bytes;
1863     if (extent->has_marker) {
1864         marker = (VmdkGrainMarker *)cluster_buf;
1865         compressed_data = marker->data;
1866         data_len = le32_to_cpu(marker->size);
1867     }
1868     if (!data_len || data_len > buf_bytes) {
1869         ret = -EINVAL;
1870         goto out;
1871     }
1872     ret = uncompress(uncomp_buf, &buf_len, compressed_data, data_len);
1873     if (ret != Z_OK) {
1874         ret = -EINVAL;
1875         goto out;
1876 
1877     }
1878     if (offset_in_cluster < 0 ||
1879             offset_in_cluster + bytes > buf_len) {
1880         ret = -EINVAL;
1881         goto out;
1882     }
1883     qemu_iovec_from_buf(qiov, 0, uncomp_buf + offset_in_cluster, bytes);
1884     ret = 0;
1885 
1886  out:
1887     g_free(uncomp_buf);
1888     g_free(cluster_buf);
1889     return ret;
1890 }
1891 
1892 static int coroutine_fn
1893 vmdk_co_preadv(BlockDriverState *bs, int64_t offset, int64_t bytes,
1894                QEMUIOVector *qiov, BdrvRequestFlags flags)
1895 {
1896     BDRVVmdkState *s = bs->opaque;
1897     int ret;
1898     uint64_t n_bytes, offset_in_cluster;
1899     VmdkExtent *extent = NULL;
1900     QEMUIOVector local_qiov;
1901     uint64_t cluster_offset;
1902     uint64_t bytes_done = 0;
1903 
1904     qemu_iovec_init(&local_qiov, qiov->niov);
1905     qemu_co_mutex_lock(&s->lock);
1906 
1907     while (bytes > 0) {
1908         extent = find_extent(s, offset >> BDRV_SECTOR_BITS, extent);
1909         if (!extent) {
1910             ret = -EIO;
1911             goto fail;
1912         }
1913         ret = get_cluster_offset(bs, extent, NULL,
1914                                  offset, false, &cluster_offset, 0, 0);
1915         offset_in_cluster = vmdk_find_offset_in_cluster(extent, offset);
1916 
1917         n_bytes = MIN(bytes, extent->cluster_sectors * BDRV_SECTOR_SIZE
1918                              - offset_in_cluster);
1919 
1920         if (ret != VMDK_OK) {
1921             /* if not allocated, try to read from parent image, if exist */
1922             if (bs->backing && ret != VMDK_ZEROED) {
1923                 if (!vmdk_is_cid_valid(bs)) {
1924                     ret = -EINVAL;
1925                     goto fail;
1926                 }
1927 
1928                 qemu_iovec_reset(&local_qiov);
1929                 qemu_iovec_concat(&local_qiov, qiov, bytes_done, n_bytes);
1930 
1931                 /* qcow2 emits this on bs->file instead of bs->backing */
1932                 BLKDBG_EVENT(bs->file, BLKDBG_READ_BACKING_AIO);
1933                 ret = bdrv_co_preadv(bs->backing, offset, n_bytes,
1934                                      &local_qiov, 0);
1935                 if (ret < 0) {
1936                     goto fail;
1937                 }
1938             } else {
1939                 qemu_iovec_memset(qiov, bytes_done, 0, n_bytes);
1940             }
1941         } else {
1942             qemu_iovec_reset(&local_qiov);
1943             qemu_iovec_concat(&local_qiov, qiov, bytes_done, n_bytes);
1944 
1945             ret = vmdk_read_extent(extent, cluster_offset, offset_in_cluster,
1946                                    &local_qiov, n_bytes);
1947             if (ret) {
1948                 goto fail;
1949             }
1950         }
1951         bytes -= n_bytes;
1952         offset += n_bytes;
1953         bytes_done += n_bytes;
1954     }
1955 
1956     ret = 0;
1957 fail:
1958     qemu_co_mutex_unlock(&s->lock);
1959     qemu_iovec_destroy(&local_qiov);
1960 
1961     return ret;
1962 }
1963 
1964 /**
1965  * vmdk_write:
1966  * @zeroed:       buf is ignored (data is zero), use zeroed_grain GTE feature
1967  *                if possible, otherwise return -ENOTSUP.
1968  * @zero_dry_run: used for zeroed == true only, don't update L2 table, just try
1969  *                with each cluster. By dry run we can find if the zero write
1970  *                is possible without modifying image data.
1971  *
1972  * Returns: error code with 0 for success.
1973  */
1974 static int vmdk_pwritev(BlockDriverState *bs, uint64_t offset,
1975                        uint64_t bytes, QEMUIOVector *qiov,
1976                        bool zeroed, bool zero_dry_run)
1977 {
1978     BDRVVmdkState *s = bs->opaque;
1979     VmdkExtent *extent = NULL;
1980     int ret;
1981     int64_t offset_in_cluster, n_bytes;
1982     uint64_t cluster_offset;
1983     uint64_t bytes_done = 0;
1984     VmdkMetaData m_data;
1985 
1986     if (DIV_ROUND_UP(offset, BDRV_SECTOR_SIZE) > bs->total_sectors) {
1987         error_report("Wrong offset: offset=0x%" PRIx64
1988                      " total_sectors=0x%" PRIx64,
1989                      offset, bs->total_sectors);
1990         return -EIO;
1991     }
1992 
1993     while (bytes > 0) {
1994         extent = find_extent(s, offset >> BDRV_SECTOR_BITS, extent);
1995         if (!extent) {
1996             return -EIO;
1997         }
1998         if (extent->sesparse) {
1999             return -ENOTSUP;
2000         }
2001         offset_in_cluster = vmdk_find_offset_in_cluster(extent, offset);
2002         n_bytes = MIN(bytes, extent->cluster_sectors * BDRV_SECTOR_SIZE
2003                              - offset_in_cluster);
2004 
2005         ret = get_cluster_offset(bs, extent, &m_data, offset,
2006                                  !(extent->compressed || zeroed),
2007                                  &cluster_offset, offset_in_cluster,
2008                                  offset_in_cluster + n_bytes);
2009         if (extent->compressed) {
2010             if (ret == VMDK_OK) {
2011                 /* Refuse write to allocated cluster for streamOptimized */
2012                 error_report("Could not write to allocated cluster"
2013                               " for streamOptimized");
2014                 return -EIO;
2015             } else if (!zeroed) {
2016                 /* allocate */
2017                 ret = get_cluster_offset(bs, extent, &m_data, offset,
2018                                          true, &cluster_offset, 0, 0);
2019             }
2020         }
2021         if (ret == VMDK_ERROR) {
2022             return -EINVAL;
2023         }
2024         if (zeroed) {
2025             /* Do zeroed write, buf is ignored */
2026             if (extent->has_zero_grain &&
2027                     offset_in_cluster == 0 &&
2028                     n_bytes >= extent->cluster_sectors * BDRV_SECTOR_SIZE) {
2029                 n_bytes = extent->cluster_sectors * BDRV_SECTOR_SIZE;
2030                 if (!zero_dry_run && ret != VMDK_ZEROED) {
2031                     /* update L2 tables */
2032                     if (vmdk_L2update(extent, &m_data, VMDK_GTE_ZEROED)
2033                             != VMDK_OK) {
2034                         return -EIO;
2035                     }
2036                 }
2037             } else {
2038                 return -ENOTSUP;
2039             }
2040         } else {
2041             ret = vmdk_write_extent(extent, cluster_offset, offset_in_cluster,
2042                                     qiov, bytes_done, n_bytes, offset);
2043             if (ret) {
2044                 return ret;
2045             }
2046             if (m_data.new_allocation) {
2047                 /* update L2 tables */
2048                 if (vmdk_L2update(extent, &m_data,
2049                                   cluster_offset >> BDRV_SECTOR_BITS)
2050                         != VMDK_OK) {
2051                     return -EIO;
2052                 }
2053             }
2054         }
2055         bytes -= n_bytes;
2056         offset += n_bytes;
2057         bytes_done += n_bytes;
2058 
2059         /* update CID on the first write every time the virtual disk is
2060          * opened */
2061         if (!s->cid_updated) {
2062             ret = vmdk_write_cid(bs, g_random_int());
2063             if (ret < 0) {
2064                 return ret;
2065             }
2066             s->cid_updated = true;
2067         }
2068     }
2069     return 0;
2070 }
2071 
2072 static int coroutine_fn
2073 vmdk_co_pwritev(BlockDriverState *bs, int64_t offset, int64_t bytes,
2074                 QEMUIOVector *qiov, BdrvRequestFlags flags)
2075 {
2076     int ret;
2077     BDRVVmdkState *s = bs->opaque;
2078     qemu_co_mutex_lock(&s->lock);
2079     ret = vmdk_pwritev(bs, offset, bytes, qiov, false, false);
2080     qemu_co_mutex_unlock(&s->lock);
2081     return ret;
2082 }
2083 
2084 static int coroutine_fn
2085 vmdk_co_pwritev_compressed(BlockDriverState *bs, int64_t offset, int64_t bytes,
2086                            QEMUIOVector *qiov)
2087 {
2088     if (bytes == 0) {
2089         /* The caller will write bytes 0 to signal EOF.
2090          * When receive it, we align EOF to a sector boundary. */
2091         BDRVVmdkState *s = bs->opaque;
2092         int i, ret;
2093         int64_t length;
2094 
2095         for (i = 0; i < s->num_extents; i++) {
2096             length = bdrv_getlength(s->extents[i].file->bs);
2097             if (length < 0) {
2098                 return length;
2099             }
2100             length = QEMU_ALIGN_UP(length, BDRV_SECTOR_SIZE);
2101             ret = bdrv_truncate(s->extents[i].file, length, false,
2102                                 PREALLOC_MODE_OFF, 0, NULL);
2103             if (ret < 0) {
2104                 return ret;
2105             }
2106         }
2107         return 0;
2108     }
2109     return vmdk_co_pwritev(bs, offset, bytes, qiov, 0);
2110 }
2111 
2112 static int coroutine_fn vmdk_co_pwrite_zeroes(BlockDriverState *bs,
2113                                               int64_t offset,
2114                                               int64_t bytes,
2115                                               BdrvRequestFlags flags)
2116 {
2117     int ret;
2118     BDRVVmdkState *s = bs->opaque;
2119 
2120     qemu_co_mutex_lock(&s->lock);
2121     /* write zeroes could fail if sectors not aligned to cluster, test it with
2122      * dry_run == true before really updating image */
2123     ret = vmdk_pwritev(bs, offset, bytes, NULL, true, true);
2124     if (!ret) {
2125         ret = vmdk_pwritev(bs, offset, bytes, NULL, true, false);
2126     }
2127     qemu_co_mutex_unlock(&s->lock);
2128     return ret;
2129 }
2130 
2131 static int vmdk_init_extent(BlockBackend *blk,
2132                             int64_t filesize, bool flat,
2133                             bool compress, bool zeroed_grain,
2134                             Error **errp)
2135 {
2136     int ret, i;
2137     VMDK4Header header;
2138     uint32_t tmp, magic, grains, gd_sectors, gt_size, gt_count;
2139     uint32_t *gd_buf = NULL;
2140     int gd_buf_size;
2141 
2142     if (flat) {
2143         ret = blk_truncate(blk, filesize, false, PREALLOC_MODE_OFF, 0, errp);
2144         goto exit;
2145     }
2146     magic = cpu_to_be32(VMDK4_MAGIC);
2147     memset(&header, 0, sizeof(header));
2148     if (compress) {
2149         header.version = 3;
2150     } else if (zeroed_grain) {
2151         header.version = 2;
2152     } else {
2153         header.version = 1;
2154     }
2155     header.flags = VMDK4_FLAG_RGD | VMDK4_FLAG_NL_DETECT
2156                    | (compress ? VMDK4_FLAG_COMPRESS | VMDK4_FLAG_MARKER : 0)
2157                    | (zeroed_grain ? VMDK4_FLAG_ZERO_GRAIN : 0);
2158     header.compressAlgorithm = compress ? VMDK4_COMPRESSION_DEFLATE : 0;
2159     header.capacity = filesize / BDRV_SECTOR_SIZE;
2160     header.granularity = 128;
2161     header.num_gtes_per_gt = BDRV_SECTOR_SIZE;
2162 
2163     grains = DIV_ROUND_UP(filesize / BDRV_SECTOR_SIZE, header.granularity);
2164     gt_size = DIV_ROUND_UP(header.num_gtes_per_gt * sizeof(uint32_t),
2165                            BDRV_SECTOR_SIZE);
2166     gt_count = DIV_ROUND_UP(grains, header.num_gtes_per_gt);
2167     gd_sectors = DIV_ROUND_UP(gt_count * sizeof(uint32_t), BDRV_SECTOR_SIZE);
2168 
2169     header.desc_offset = 1;
2170     header.desc_size = 20;
2171     header.rgd_offset = header.desc_offset + header.desc_size;
2172     header.gd_offset = header.rgd_offset + gd_sectors + (gt_size * gt_count);
2173     header.grain_offset =
2174         ROUND_UP(header.gd_offset + gd_sectors + (gt_size * gt_count),
2175                  header.granularity);
2176     /* swap endianness for all header fields */
2177     header.version = cpu_to_le32(header.version);
2178     header.flags = cpu_to_le32(header.flags);
2179     header.capacity = cpu_to_le64(header.capacity);
2180     header.granularity = cpu_to_le64(header.granularity);
2181     header.num_gtes_per_gt = cpu_to_le32(header.num_gtes_per_gt);
2182     header.desc_offset = cpu_to_le64(header.desc_offset);
2183     header.desc_size = cpu_to_le64(header.desc_size);
2184     header.rgd_offset = cpu_to_le64(header.rgd_offset);
2185     header.gd_offset = cpu_to_le64(header.gd_offset);
2186     header.grain_offset = cpu_to_le64(header.grain_offset);
2187     header.compressAlgorithm = cpu_to_le16(header.compressAlgorithm);
2188 
2189     header.check_bytes[0] = 0xa;
2190     header.check_bytes[1] = 0x20;
2191     header.check_bytes[2] = 0xd;
2192     header.check_bytes[3] = 0xa;
2193 
2194     /* write all the data */
2195     ret = blk_pwrite(blk, 0, &magic, sizeof(magic), 0);
2196     if (ret < 0) {
2197         error_setg(errp, QERR_IO_ERROR);
2198         goto exit;
2199     }
2200     ret = blk_pwrite(blk, sizeof(magic), &header, sizeof(header), 0);
2201     if (ret < 0) {
2202         error_setg(errp, QERR_IO_ERROR);
2203         goto exit;
2204     }
2205 
2206     ret = blk_truncate(blk, le64_to_cpu(header.grain_offset) << 9, false,
2207                        PREALLOC_MODE_OFF, 0, errp);
2208     if (ret < 0) {
2209         goto exit;
2210     }
2211 
2212     /* write grain directory */
2213     gd_buf_size = gd_sectors * BDRV_SECTOR_SIZE;
2214     gd_buf = g_malloc0(gd_buf_size);
2215     for (i = 0, tmp = le64_to_cpu(header.rgd_offset) + gd_sectors;
2216          i < gt_count; i++, tmp += gt_size) {
2217         gd_buf[i] = cpu_to_le32(tmp);
2218     }
2219     ret = blk_pwrite(blk, le64_to_cpu(header.rgd_offset) * BDRV_SECTOR_SIZE,
2220                      gd_buf, gd_buf_size, 0);
2221     if (ret < 0) {
2222         error_setg(errp, QERR_IO_ERROR);
2223         goto exit;
2224     }
2225 
2226     /* write backup grain directory */
2227     for (i = 0, tmp = le64_to_cpu(header.gd_offset) + gd_sectors;
2228          i < gt_count; i++, tmp += gt_size) {
2229         gd_buf[i] = cpu_to_le32(tmp);
2230     }
2231     ret = blk_pwrite(blk, le64_to_cpu(header.gd_offset) * BDRV_SECTOR_SIZE,
2232                      gd_buf, gd_buf_size, 0);
2233     if (ret < 0) {
2234         error_setg(errp, QERR_IO_ERROR);
2235     }
2236 
2237     ret = 0;
2238 exit:
2239     g_free(gd_buf);
2240     return ret;
2241 }
2242 
2243 static int vmdk_create_extent(const char *filename, int64_t filesize,
2244                               bool flat, bool compress, bool zeroed_grain,
2245                               BlockBackend **pbb,
2246                               QemuOpts *opts, Error **errp)
2247 {
2248     int ret;
2249     BlockBackend *blk = NULL;
2250 
2251     ret = bdrv_create_file(filename, opts, errp);
2252     if (ret < 0) {
2253         goto exit;
2254     }
2255 
2256     blk = blk_new_open(filename, NULL, NULL,
2257                        BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL,
2258                        errp);
2259     if (blk == NULL) {
2260         ret = -EIO;
2261         goto exit;
2262     }
2263 
2264     blk_set_allow_write_beyond_eof(blk, true);
2265 
2266     ret = vmdk_init_extent(blk, filesize, flat, compress, zeroed_grain, errp);
2267 exit:
2268     if (blk) {
2269         if (pbb) {
2270             *pbb = blk;
2271         } else {
2272             blk_unref(blk);
2273             blk = NULL;
2274         }
2275     }
2276     return ret;
2277 }
2278 
2279 static int filename_decompose(const char *filename, char *path, char *prefix,
2280                               char *postfix, size_t buf_len, Error **errp)
2281 {
2282     const char *p, *q;
2283 
2284     if (filename == NULL || !strlen(filename)) {
2285         error_setg(errp, "No filename provided");
2286         return VMDK_ERROR;
2287     }
2288     p = strrchr(filename, '/');
2289     if (p == NULL) {
2290         p = strrchr(filename, '\\');
2291     }
2292     if (p == NULL) {
2293         p = strrchr(filename, ':');
2294     }
2295     if (p != NULL) {
2296         p++;
2297         if (p - filename >= buf_len) {
2298             return VMDK_ERROR;
2299         }
2300         pstrcpy(path, p - filename + 1, filename);
2301     } else {
2302         p = filename;
2303         path[0] = '\0';
2304     }
2305     q = strrchr(p, '.');
2306     if (q == NULL) {
2307         pstrcpy(prefix, buf_len, p);
2308         postfix[0] = '\0';
2309     } else {
2310         if (q - p >= buf_len) {
2311             return VMDK_ERROR;
2312         }
2313         pstrcpy(prefix, q - p + 1, p);
2314         pstrcpy(postfix, buf_len, q);
2315     }
2316     return VMDK_OK;
2317 }
2318 
2319 /*
2320  * idx == 0: get or create the descriptor file (also the image file if in a
2321  *           non-split format.
2322  * idx >= 1: get the n-th extent if in a split subformat
2323  */
2324 typedef BlockBackend *(*vmdk_create_extent_fn)(int64_t size,
2325                                                int idx,
2326                                                bool flat,
2327                                                bool split,
2328                                                bool compress,
2329                                                bool zeroed_grain,
2330                                                void *opaque,
2331                                                Error **errp);
2332 
2333 static void vmdk_desc_add_extent(GString *desc,
2334                                  const char *extent_line_fmt,
2335                                  int64_t size, const char *filename)
2336 {
2337     char *basename = g_path_get_basename(filename);
2338 
2339     g_string_append_printf(desc, extent_line_fmt,
2340                            DIV_ROUND_UP(size, BDRV_SECTOR_SIZE), basename);
2341     g_free(basename);
2342 }
2343 
2344 static int coroutine_fn vmdk_co_do_create(int64_t size,
2345                                           BlockdevVmdkSubformat subformat,
2346                                           BlockdevVmdkAdapterType adapter_type,
2347                                           const char *backing_file,
2348                                           const char *hw_version,
2349                                           const char *toolsversion,
2350                                           bool compat6,
2351                                           bool zeroed_grain,
2352                                           vmdk_create_extent_fn extent_fn,
2353                                           void *opaque,
2354                                           Error **errp)
2355 {
2356     int extent_idx;
2357     BlockBackend *blk = NULL;
2358     BlockBackend *extent_blk;
2359     Error *local_err = NULL;
2360     char *desc = NULL;
2361     int ret = 0;
2362     bool flat, split, compress;
2363     GString *ext_desc_lines;
2364     const int64_t split_size = 0x80000000;  /* VMDK has constant split size */
2365     int64_t extent_size;
2366     int64_t created_size = 0;
2367     const char *extent_line_fmt;
2368     char *parent_desc_line = g_malloc0(BUF_SIZE);
2369     uint32_t parent_cid = 0xffffffff;
2370     uint32_t number_heads = 16;
2371     uint32_t desc_offset = 0, desc_len;
2372     const char desc_template[] =
2373         "# Disk DescriptorFile\n"
2374         "version=1\n"
2375         "CID=%" PRIx32 "\n"
2376         "parentCID=%" PRIx32 "\n"
2377         "createType=\"%s\"\n"
2378         "%s"
2379         "\n"
2380         "# Extent description\n"
2381         "%s"
2382         "\n"
2383         "# The Disk Data Base\n"
2384         "#DDB\n"
2385         "\n"
2386         "ddb.virtualHWVersion = \"%s\"\n"
2387         "ddb.geometry.cylinders = \"%" PRId64 "\"\n"
2388         "ddb.geometry.heads = \"%" PRIu32 "\"\n"
2389         "ddb.geometry.sectors = \"63\"\n"
2390         "ddb.adapterType = \"%s\"\n"
2391         "ddb.toolsVersion = \"%s\"\n";
2392 
2393     ext_desc_lines = g_string_new(NULL);
2394 
2395     /* Read out options */
2396     if (compat6) {
2397         if (hw_version) {
2398             error_setg(errp,
2399                        "compat6 cannot be enabled with hwversion set");
2400             ret = -EINVAL;
2401             goto exit;
2402         }
2403         hw_version = "6";
2404     }
2405     if (!hw_version) {
2406         hw_version = "4";
2407     }
2408     if (!toolsversion) {
2409         toolsversion = "2147483647";
2410     }
2411 
2412     if (adapter_type != BLOCKDEV_VMDK_ADAPTER_TYPE_IDE) {
2413         /* that's the number of heads with which vmware operates when
2414            creating, exporting, etc. vmdk files with a non-ide adapter type */
2415         number_heads = 255;
2416     }
2417     split = (subformat == BLOCKDEV_VMDK_SUBFORMAT_TWOGBMAXEXTENTFLAT) ||
2418             (subformat == BLOCKDEV_VMDK_SUBFORMAT_TWOGBMAXEXTENTSPARSE);
2419     flat = (subformat == BLOCKDEV_VMDK_SUBFORMAT_MONOLITHICFLAT) ||
2420            (subformat == BLOCKDEV_VMDK_SUBFORMAT_TWOGBMAXEXTENTFLAT);
2421     compress = subformat == BLOCKDEV_VMDK_SUBFORMAT_STREAMOPTIMIZED;
2422 
2423     if (flat) {
2424         extent_line_fmt = "RW %" PRId64 " FLAT \"%s\" 0\n";
2425     } else {
2426         extent_line_fmt = "RW %" PRId64 " SPARSE \"%s\"\n";
2427     }
2428     if (flat && backing_file) {
2429         error_setg(errp, "Flat image can't have backing file");
2430         ret = -ENOTSUP;
2431         goto exit;
2432     }
2433     if (flat && zeroed_grain) {
2434         error_setg(errp, "Flat image can't enable zeroed grain");
2435         ret = -ENOTSUP;
2436         goto exit;
2437     }
2438 
2439     /* Create extents */
2440     if (split) {
2441         extent_size = split_size;
2442     } else {
2443         extent_size = size;
2444     }
2445     if (!split && !flat) {
2446         created_size = extent_size;
2447     } else {
2448         created_size = 0;
2449     }
2450     /* Get the descriptor file BDS */
2451     blk = extent_fn(created_size, 0, flat, split, compress, zeroed_grain,
2452                     opaque, errp);
2453     if (!blk) {
2454         ret = -EIO;
2455         goto exit;
2456     }
2457     if (!split && !flat) {
2458         vmdk_desc_add_extent(ext_desc_lines, extent_line_fmt, created_size,
2459                              blk_bs(blk)->filename);
2460     }
2461 
2462     if (backing_file) {
2463         BlockBackend *backing;
2464         char *full_backing =
2465             bdrv_get_full_backing_filename_from_filename(blk_bs(blk)->filename,
2466                                                          backing_file,
2467                                                          &local_err);
2468         if (local_err) {
2469             error_propagate(errp, local_err);
2470             ret = -ENOENT;
2471             goto exit;
2472         }
2473         assert(full_backing);
2474 
2475         backing = blk_new_open(full_backing, NULL, NULL,
2476                                BDRV_O_NO_BACKING, errp);
2477         g_free(full_backing);
2478         if (backing == NULL) {
2479             ret = -EIO;
2480             goto exit;
2481         }
2482         if (strcmp(blk_bs(backing)->drv->format_name, "vmdk")) {
2483             error_setg(errp, "Invalid backing file format: %s. Must be vmdk",
2484                        blk_bs(backing)->drv->format_name);
2485             blk_unref(backing);
2486             ret = -EINVAL;
2487             goto exit;
2488         }
2489         ret = vmdk_read_cid(blk_bs(backing), 0, &parent_cid);
2490         blk_unref(backing);
2491         if (ret) {
2492             error_setg(errp, "Failed to read parent CID");
2493             goto exit;
2494         }
2495         snprintf(parent_desc_line, BUF_SIZE,
2496                 "parentFileNameHint=\"%s\"", backing_file);
2497     }
2498     extent_idx = 1;
2499     while (created_size < size) {
2500         int64_t cur_size = MIN(size - created_size, extent_size);
2501         extent_blk = extent_fn(cur_size, extent_idx, flat, split, compress,
2502                                zeroed_grain, opaque, errp);
2503         if (!extent_blk) {
2504             ret = -EINVAL;
2505             goto exit;
2506         }
2507         vmdk_desc_add_extent(ext_desc_lines, extent_line_fmt, cur_size,
2508                              blk_bs(extent_blk)->filename);
2509         created_size += cur_size;
2510         extent_idx++;
2511         blk_unref(extent_blk);
2512     }
2513 
2514     /* Check whether we got excess extents */
2515     extent_blk = extent_fn(-1, extent_idx, flat, split, compress, zeroed_grain,
2516                            opaque, NULL);
2517     if (extent_blk) {
2518         blk_unref(extent_blk);
2519         error_setg(errp, "List of extents contains unused extents");
2520         ret = -EINVAL;
2521         goto exit;
2522     }
2523 
2524     /* generate descriptor file */
2525     desc = g_strdup_printf(desc_template,
2526                            g_random_int(),
2527                            parent_cid,
2528                            BlockdevVmdkSubformat_str(subformat),
2529                            parent_desc_line,
2530                            ext_desc_lines->str,
2531                            hw_version,
2532                            size /
2533                                (int64_t)(63 * number_heads * BDRV_SECTOR_SIZE),
2534                            number_heads,
2535                            BlockdevVmdkAdapterType_str(adapter_type),
2536                            toolsversion);
2537     desc_len = strlen(desc);
2538     /* the descriptor offset = 0x200 */
2539     if (!split && !flat) {
2540         desc_offset = 0x200;
2541     }
2542 
2543     ret = blk_pwrite(blk, desc_offset, desc, desc_len, 0);
2544     if (ret < 0) {
2545         error_setg_errno(errp, -ret, "Could not write description");
2546         goto exit;
2547     }
2548     /* bdrv_pwrite write padding zeros to align to sector, we don't need that
2549      * for description file */
2550     if (desc_offset == 0) {
2551         ret = blk_truncate(blk, desc_len, false, PREALLOC_MODE_OFF, 0, errp);
2552         if (ret < 0) {
2553             goto exit;
2554         }
2555     }
2556     ret = 0;
2557 exit:
2558     if (blk) {
2559         blk_unref(blk);
2560     }
2561     g_free(desc);
2562     g_free(parent_desc_line);
2563     g_string_free(ext_desc_lines, true);
2564     return ret;
2565 }
2566 
2567 typedef struct {
2568     char *path;
2569     char *prefix;
2570     char *postfix;
2571     QemuOpts *opts;
2572 } VMDKCreateOptsData;
2573 
2574 static BlockBackend *vmdk_co_create_opts_cb(int64_t size, int idx,
2575                                             bool flat, bool split, bool compress,
2576                                             bool zeroed_grain, void *opaque,
2577                                             Error **errp)
2578 {
2579     BlockBackend *blk = NULL;
2580     BlockDriverState *bs = NULL;
2581     VMDKCreateOptsData *data = opaque;
2582     char *ext_filename = NULL;
2583     char *rel_filename = NULL;
2584 
2585     /* We're done, don't create excess extents. */
2586     if (size == -1) {
2587         assert(errp == NULL);
2588         return NULL;
2589     }
2590 
2591     if (idx == 0) {
2592         rel_filename = g_strdup_printf("%s%s", data->prefix, data->postfix);
2593     } else if (split) {
2594         rel_filename = g_strdup_printf("%s-%c%03d%s",
2595                                        data->prefix,
2596                                        flat ? 'f' : 's', idx, data->postfix);
2597     } else {
2598         assert(idx == 1);
2599         rel_filename = g_strdup_printf("%s-flat%s", data->prefix, data->postfix);
2600     }
2601 
2602     ext_filename = g_strdup_printf("%s%s", data->path, rel_filename);
2603     g_free(rel_filename);
2604 
2605     if (vmdk_create_extent(ext_filename, size,
2606                            flat, compress, zeroed_grain, &blk, data->opts,
2607                            errp)) {
2608         goto exit;
2609     }
2610     bdrv_unref(bs);
2611 exit:
2612     g_free(ext_filename);
2613     return blk;
2614 }
2615 
2616 static int coroutine_fn vmdk_co_create_opts(BlockDriver *drv,
2617                                             const char *filename,
2618                                             QemuOpts *opts,
2619                                             Error **errp)
2620 {
2621     Error *local_err = NULL;
2622     char *desc = NULL;
2623     int64_t total_size = 0;
2624     char *adapter_type = NULL;
2625     BlockdevVmdkAdapterType adapter_type_enum;
2626     char *backing_file = NULL;
2627     char *hw_version = NULL;
2628     char *toolsversion = NULL;
2629     char *fmt = NULL;
2630     BlockdevVmdkSubformat subformat;
2631     int ret = 0;
2632     char *path = g_malloc0(PATH_MAX);
2633     char *prefix = g_malloc0(PATH_MAX);
2634     char *postfix = g_malloc0(PATH_MAX);
2635     char *desc_line = g_malloc0(BUF_SIZE);
2636     char *ext_filename = g_malloc0(PATH_MAX);
2637     char *desc_filename = g_malloc0(PATH_MAX);
2638     char *parent_desc_line = g_malloc0(BUF_SIZE);
2639     bool zeroed_grain;
2640     bool compat6;
2641     VMDKCreateOptsData data;
2642     char *backing_fmt = NULL;
2643 
2644     backing_fmt = qemu_opt_get_del(opts, BLOCK_OPT_BACKING_FMT);
2645     if (backing_fmt && strcmp(backing_fmt, "vmdk") != 0) {
2646         error_setg(errp, "backing_file must be a vmdk image");
2647         ret = -EINVAL;
2648         goto exit;
2649     }
2650 
2651     if (filename_decompose(filename, path, prefix, postfix, PATH_MAX, errp)) {
2652         ret = -EINVAL;
2653         goto exit;
2654     }
2655     /* Read out options */
2656     total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
2657                           BDRV_SECTOR_SIZE);
2658     adapter_type = qemu_opt_get_del(opts, BLOCK_OPT_ADAPTER_TYPE);
2659     backing_file = qemu_opt_get_del(opts, BLOCK_OPT_BACKING_FILE);
2660     hw_version = qemu_opt_get_del(opts, BLOCK_OPT_HWVERSION);
2661     toolsversion = qemu_opt_get_del(opts, BLOCK_OPT_TOOLSVERSION);
2662     compat6 = qemu_opt_get_bool_del(opts, BLOCK_OPT_COMPAT6, false);
2663     if (strcmp(hw_version, "undefined") == 0) {
2664         g_free(hw_version);
2665         hw_version = NULL;
2666     }
2667     fmt = qemu_opt_get_del(opts, BLOCK_OPT_SUBFMT);
2668     zeroed_grain = qemu_opt_get_bool_del(opts, BLOCK_OPT_ZEROED_GRAIN, false);
2669 
2670     if (adapter_type) {
2671         adapter_type_enum = qapi_enum_parse(&BlockdevVmdkAdapterType_lookup,
2672                                             adapter_type,
2673                                             BLOCKDEV_VMDK_ADAPTER_TYPE_IDE,
2674                                             &local_err);
2675         if (local_err) {
2676             error_propagate(errp, local_err);
2677             ret = -EINVAL;
2678             goto exit;
2679         }
2680     } else {
2681         adapter_type_enum = BLOCKDEV_VMDK_ADAPTER_TYPE_IDE;
2682     }
2683 
2684     if (!fmt) {
2685         /* Default format to monolithicSparse */
2686         subformat = BLOCKDEV_VMDK_SUBFORMAT_MONOLITHICSPARSE;
2687     } else {
2688         subformat = qapi_enum_parse(&BlockdevVmdkSubformat_lookup,
2689                                     fmt,
2690                                     BLOCKDEV_VMDK_SUBFORMAT_MONOLITHICSPARSE,
2691                                     &local_err);
2692         if (local_err) {
2693             error_propagate(errp, local_err);
2694             ret = -EINVAL;
2695             goto exit;
2696         }
2697     }
2698     data = (VMDKCreateOptsData){
2699         .prefix = prefix,
2700         .postfix = postfix,
2701         .path = path,
2702         .opts = opts,
2703     };
2704     ret = vmdk_co_do_create(total_size, subformat, adapter_type_enum,
2705                             backing_file, hw_version, toolsversion, compat6,
2706                             zeroed_grain, vmdk_co_create_opts_cb, &data, errp);
2707 
2708 exit:
2709     g_free(backing_fmt);
2710     g_free(adapter_type);
2711     g_free(backing_file);
2712     g_free(hw_version);
2713     g_free(toolsversion);
2714     g_free(fmt);
2715     g_free(desc);
2716     g_free(path);
2717     g_free(prefix);
2718     g_free(postfix);
2719     g_free(desc_line);
2720     g_free(ext_filename);
2721     g_free(desc_filename);
2722     g_free(parent_desc_line);
2723     return ret;
2724 }
2725 
2726 static BlockBackend *vmdk_co_create_cb(int64_t size, int idx,
2727                                        bool flat, bool split, bool compress,
2728                                        bool zeroed_grain, void *opaque,
2729                                        Error **errp)
2730 {
2731     int ret;
2732     BlockDriverState *bs;
2733     BlockBackend *blk;
2734     BlockdevCreateOptionsVmdk *opts = opaque;
2735 
2736     if (idx == 0) {
2737         bs = bdrv_open_blockdev_ref(opts->file, errp);
2738     } else {
2739         int i;
2740         BlockdevRefList *list = opts->extents;
2741         for (i = 1; i < idx; i++) {
2742             if (!list || !list->next) {
2743                 error_setg(errp, "Extent [%d] not specified", i);
2744                 return NULL;
2745             }
2746             list = list->next;
2747         }
2748         if (!list) {
2749             error_setg(errp, "Extent [%d] not specified", idx - 1);
2750             return NULL;
2751         }
2752         bs = bdrv_open_blockdev_ref(list->value, errp);
2753     }
2754     if (!bs) {
2755         return NULL;
2756     }
2757     blk = blk_new_with_bs(bs,
2758                           BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE | BLK_PERM_RESIZE,
2759                           BLK_PERM_ALL, errp);
2760     if (!blk) {
2761         return NULL;
2762     }
2763     blk_set_allow_write_beyond_eof(blk, true);
2764     bdrv_unref(bs);
2765 
2766     if (size != -1) {
2767         ret = vmdk_init_extent(blk, size, flat, compress, zeroed_grain, errp);
2768         if (ret) {
2769             blk_unref(blk);
2770             blk = NULL;
2771         }
2772     }
2773     return blk;
2774 }
2775 
2776 static int coroutine_fn vmdk_co_create(BlockdevCreateOptions *create_options,
2777                                        Error **errp)
2778 {
2779     int ret;
2780     BlockdevCreateOptionsVmdk *opts;
2781 
2782     opts = &create_options->u.vmdk;
2783 
2784     /* Validate options */
2785     if (!QEMU_IS_ALIGNED(opts->size, BDRV_SECTOR_SIZE)) {
2786         error_setg(errp, "Image size must be a multiple of 512 bytes");
2787         ret = -EINVAL;
2788         goto out;
2789     }
2790 
2791     ret = vmdk_co_do_create(opts->size,
2792                             opts->subformat,
2793                             opts->adapter_type,
2794                             opts->backing_file,
2795                             opts->hwversion,
2796                             opts->toolsversion,
2797                             false,
2798                             opts->zeroed_grain,
2799                             vmdk_co_create_cb,
2800                             opts, errp);
2801     return ret;
2802 
2803 out:
2804     return ret;
2805 }
2806 
2807 static void vmdk_close(BlockDriverState *bs)
2808 {
2809     BDRVVmdkState *s = bs->opaque;
2810 
2811     vmdk_free_extents(bs);
2812     g_free(s->create_type);
2813 
2814     migrate_del_blocker(s->migration_blocker);
2815     error_free(s->migration_blocker);
2816 }
2817 
2818 static int64_t vmdk_get_allocated_file_size(BlockDriverState *bs)
2819 {
2820     int i;
2821     int64_t ret = 0;
2822     int64_t r;
2823     BDRVVmdkState *s = bs->opaque;
2824 
2825     ret = bdrv_get_allocated_file_size(bs->file->bs);
2826     if (ret < 0) {
2827         return ret;
2828     }
2829     for (i = 0; i < s->num_extents; i++) {
2830         if (s->extents[i].file == bs->file) {
2831             continue;
2832         }
2833         r = bdrv_get_allocated_file_size(s->extents[i].file->bs);
2834         if (r < 0) {
2835             return r;
2836         }
2837         ret += r;
2838     }
2839     return ret;
2840 }
2841 
2842 static int vmdk_has_zero_init(BlockDriverState *bs)
2843 {
2844     int i;
2845     BDRVVmdkState *s = bs->opaque;
2846 
2847     /* If has a flat extent and its underlying storage doesn't have zero init,
2848      * return 0. */
2849     for (i = 0; i < s->num_extents; i++) {
2850         if (s->extents[i].flat) {
2851             if (!bdrv_has_zero_init(s->extents[i].file->bs)) {
2852                 return 0;
2853             }
2854         }
2855     }
2856     return 1;
2857 }
2858 
2859 static ImageInfo *vmdk_get_extent_info(VmdkExtent *extent)
2860 {
2861     ImageInfo *info = g_new0(ImageInfo, 1);
2862 
2863     bdrv_refresh_filename(extent->file->bs);
2864     *info = (ImageInfo){
2865         .filename         = g_strdup(extent->file->bs->filename),
2866         .format           = g_strdup(extent->type),
2867         .virtual_size     = extent->sectors * BDRV_SECTOR_SIZE,
2868         .compressed       = extent->compressed,
2869         .has_compressed   = extent->compressed,
2870         .cluster_size     = extent->cluster_sectors * BDRV_SECTOR_SIZE,
2871         .has_cluster_size = !extent->flat,
2872     };
2873 
2874     return info;
2875 }
2876 
2877 static int coroutine_fn vmdk_co_check(BlockDriverState *bs,
2878                                       BdrvCheckResult *result,
2879                                       BdrvCheckMode fix)
2880 {
2881     BDRVVmdkState *s = bs->opaque;
2882     VmdkExtent *extent = NULL;
2883     int64_t sector_num = 0;
2884     int64_t total_sectors = bdrv_nb_sectors(bs);
2885     int ret;
2886     uint64_t cluster_offset;
2887 
2888     if (fix) {
2889         return -ENOTSUP;
2890     }
2891 
2892     for (;;) {
2893         if (sector_num >= total_sectors) {
2894             return 0;
2895         }
2896         extent = find_extent(s, sector_num, extent);
2897         if (!extent) {
2898             fprintf(stderr,
2899                     "ERROR: could not find extent for sector %" PRId64 "\n",
2900                     sector_num);
2901             ret = -EINVAL;
2902             break;
2903         }
2904         ret = get_cluster_offset(bs, extent, NULL,
2905                                  sector_num << BDRV_SECTOR_BITS,
2906                                  false, &cluster_offset, 0, 0);
2907         if (ret == VMDK_ERROR) {
2908             fprintf(stderr,
2909                     "ERROR: could not get cluster_offset for sector %"
2910                     PRId64 "\n", sector_num);
2911             break;
2912         }
2913         if (ret == VMDK_OK) {
2914             int64_t extent_len = bdrv_getlength(extent->file->bs);
2915             if (extent_len < 0) {
2916                 fprintf(stderr,
2917                         "ERROR: could not get extent file length for sector %"
2918                         PRId64 "\n", sector_num);
2919                 ret = extent_len;
2920                 break;
2921             }
2922             if (cluster_offset >= extent_len) {
2923                 fprintf(stderr,
2924                         "ERROR: cluster offset for sector %"
2925                         PRId64 " points after EOF\n", sector_num);
2926                 ret = -EINVAL;
2927                 break;
2928             }
2929         }
2930         sector_num += extent->cluster_sectors;
2931     }
2932 
2933     result->corruptions++;
2934     return ret;
2935 }
2936 
2937 static ImageInfoSpecific *vmdk_get_specific_info(BlockDriverState *bs,
2938                                                  Error **errp)
2939 {
2940     int i;
2941     BDRVVmdkState *s = bs->opaque;
2942     ImageInfoSpecific *spec_info = g_new0(ImageInfoSpecific, 1);
2943     ImageInfoList **tail;
2944 
2945     *spec_info = (ImageInfoSpecific){
2946         .type = IMAGE_INFO_SPECIFIC_KIND_VMDK,
2947         .u = {
2948             .vmdk.data = g_new0(ImageInfoSpecificVmdk, 1),
2949         },
2950     };
2951 
2952     *spec_info->u.vmdk.data = (ImageInfoSpecificVmdk) {
2953         .create_type = g_strdup(s->create_type),
2954         .cid = s->cid,
2955         .parent_cid = s->parent_cid,
2956     };
2957 
2958     tail = &spec_info->u.vmdk.data->extents;
2959     for (i = 0; i < s->num_extents; i++) {
2960         QAPI_LIST_APPEND(tail, vmdk_get_extent_info(&s->extents[i]));
2961     }
2962 
2963     return spec_info;
2964 }
2965 
2966 static bool vmdk_extents_type_eq(const VmdkExtent *a, const VmdkExtent *b)
2967 {
2968     return a->flat == b->flat &&
2969            a->compressed == b->compressed &&
2970            (a->flat || a->cluster_sectors == b->cluster_sectors);
2971 }
2972 
2973 static int vmdk_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
2974 {
2975     int i;
2976     BDRVVmdkState *s = bs->opaque;
2977     assert(s->num_extents);
2978 
2979     /* See if we have multiple extents but they have different cases */
2980     for (i = 1; i < s->num_extents; i++) {
2981         if (!vmdk_extents_type_eq(&s->extents[0], &s->extents[i])) {
2982             return -ENOTSUP;
2983         }
2984     }
2985     bdi->needs_compressed_writes = s->extents[0].compressed;
2986     if (!s->extents[0].flat) {
2987         bdi->cluster_size = s->extents[0].cluster_sectors << BDRV_SECTOR_BITS;
2988     }
2989     return 0;
2990 }
2991 
2992 static void vmdk_gather_child_options(BlockDriverState *bs, QDict *target,
2993                                       bool backing_overridden)
2994 {
2995     /* No children but file and backing can be explicitly specified (TODO) */
2996     qdict_put(target, "file",
2997               qobject_ref(bs->file->bs->full_open_options));
2998 
2999     if (backing_overridden) {
3000         if (bs->backing) {
3001             qdict_put(target, "backing",
3002                       qobject_ref(bs->backing->bs->full_open_options));
3003         } else {
3004             qdict_put_null(target, "backing");
3005         }
3006     }
3007 }
3008 
3009 static QemuOptsList vmdk_create_opts = {
3010     .name = "vmdk-create-opts",
3011     .head = QTAILQ_HEAD_INITIALIZER(vmdk_create_opts.head),
3012     .desc = {
3013         {
3014             .name = BLOCK_OPT_SIZE,
3015             .type = QEMU_OPT_SIZE,
3016             .help = "Virtual disk size"
3017         },
3018         {
3019             .name = BLOCK_OPT_ADAPTER_TYPE,
3020             .type = QEMU_OPT_STRING,
3021             .help = "Virtual adapter type, can be one of "
3022                     "ide (default), lsilogic, buslogic or legacyESX"
3023         },
3024         {
3025             .name = BLOCK_OPT_BACKING_FILE,
3026             .type = QEMU_OPT_STRING,
3027             .help = "File name of a base image"
3028         },
3029         {
3030             .name = BLOCK_OPT_BACKING_FMT,
3031             .type = QEMU_OPT_STRING,
3032             .help = "Must be 'vmdk' if present",
3033         },
3034         {
3035             .name = BLOCK_OPT_COMPAT6,
3036             .type = QEMU_OPT_BOOL,
3037             .help = "VMDK version 6 image",
3038             .def_value_str = "off"
3039         },
3040         {
3041             .name = BLOCK_OPT_HWVERSION,
3042             .type = QEMU_OPT_STRING,
3043             .help = "VMDK hardware version",
3044             .def_value_str = "undefined"
3045         },
3046         {
3047             .name = BLOCK_OPT_TOOLSVERSION,
3048             .type = QEMU_OPT_STRING,
3049             .help = "VMware guest tools version",
3050         },
3051         {
3052             .name = BLOCK_OPT_SUBFMT,
3053             .type = QEMU_OPT_STRING,
3054             .help =
3055                 "VMDK flat extent format, can be one of "
3056                 "{monolithicSparse (default) | monolithicFlat | twoGbMaxExtentSparse | twoGbMaxExtentFlat | streamOptimized} "
3057         },
3058         {
3059             .name = BLOCK_OPT_ZEROED_GRAIN,
3060             .type = QEMU_OPT_BOOL,
3061             .help = "Enable efficient zero writes "
3062                     "using the zeroed-grain GTE feature"
3063         },
3064         { /* end of list */ }
3065     }
3066 };
3067 
3068 static BlockDriver bdrv_vmdk = {
3069     .format_name                  = "vmdk",
3070     .instance_size                = sizeof(BDRVVmdkState),
3071     .bdrv_probe                   = vmdk_probe,
3072     .bdrv_open                    = vmdk_open,
3073     .bdrv_co_check                = vmdk_co_check,
3074     .bdrv_reopen_prepare          = vmdk_reopen_prepare,
3075     .bdrv_child_perm              = bdrv_default_perms,
3076     .bdrv_co_preadv               = vmdk_co_preadv,
3077     .bdrv_co_pwritev              = vmdk_co_pwritev,
3078     .bdrv_co_pwritev_compressed   = vmdk_co_pwritev_compressed,
3079     .bdrv_co_pwrite_zeroes        = vmdk_co_pwrite_zeroes,
3080     .bdrv_close                   = vmdk_close,
3081     .bdrv_co_create_opts          = vmdk_co_create_opts,
3082     .bdrv_co_create               = vmdk_co_create,
3083     .bdrv_co_block_status         = vmdk_co_block_status,
3084     .bdrv_get_allocated_file_size = vmdk_get_allocated_file_size,
3085     .bdrv_has_zero_init           = vmdk_has_zero_init,
3086     .bdrv_get_specific_info       = vmdk_get_specific_info,
3087     .bdrv_refresh_limits          = vmdk_refresh_limits,
3088     .bdrv_get_info                = vmdk_get_info,
3089     .bdrv_gather_child_options    = vmdk_gather_child_options,
3090 
3091     .is_format                    = true,
3092     .supports_backing             = true,
3093     .create_opts                  = &vmdk_create_opts,
3094 };
3095 
3096 static void bdrv_vmdk_init(void)
3097 {
3098     bdrv_register(&bdrv_vmdk);
3099 }
3100 
3101 block_init(bdrv_vmdk_init);
3102