aboutsummaryrefslogtreecommitdiff
path: root/migration/vmstate.c
blob: 46dc55ea405503d73fdbad391371a2688b586057 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
#include "qemu/osdep.h"
#include "qemu-common.h"
#include "migration/migration.h"
#include "migration/qemu-file.h"
#include "migration/vmstate.h"
#include "qemu/bitops.h"
#include "qemu/error-report.h"
#include "trace.h"

static void vmstate_subsection_save(QEMUFile *f, const VMStateDescription *vmsd,
                                    void *opaque, QJSON *vmdesc);
static int vmstate_subsection_load(QEMUFile *f, const VMStateDescription *vmsd,
                                   void *opaque);

static int vmstate_n_elems(void *opaque, VMStateField *field)
{
    int n_elems = 1;

    if (field->flags & VMS_ARRAY) {
        n_elems = field->num;
    } else if (field->flags & VMS_VARRAY_INT32) {
        n_elems = *(int32_t *)(opaque+field->num_offset);
    } else if (field->flags & VMS_VARRAY_UINT32) {
        n_elems = *(uint32_t *)(opaque+field->num_offset);
    } else if (field->flags & VMS_VARRAY_UINT16) {
        n_elems = *(uint16_t *)(opaque+field->num_offset);
    } else if (field->flags & VMS_VARRAY_UINT8) {
        n_elems = *(uint8_t *)(opaque+field->num_offset);
    }

    if (field->flags & VMS_MULTIPLY_ELEMENTS) {
        n_elems *= field->num;
    }

    return n_elems;
}

static int vmstate_size(void *opaque, VMStateField *field)
{
    int size = field->size;

    if (field->flags & VMS_VBUFFER) {
        size = *(int32_t *)(opaque+field->size_offset);
        if (field->flags & VMS_MULTIPLY) {
            size *= field->size;
        }
    }

    return size;
}

static void *vmstate_base_addr(void *opaque, VMStateField *field, bool alloc)
{
    void *base_addr = opaque + field->offset;

    if (field->flags & VMS_POINTER) {
        if (alloc && (field->flags & VMS_ALLOC)) {
            gsize size = 0;
            if (field->flags & VMS_VBUFFER) {
                size = vmstate_size(opaque, field);
            } else {
                int n_elems = vmstate_n_elems(opaque, field);
                if (n_elems) {
                    size = n_elems * field->size;
                }
            }
            if (size) {
                *((void **)base_addr + field->start) = g_malloc(size);
            }
        }
        base_addr = *(void **)base_addr + field->start;
    }

    return base_addr;
}

int vmstate_load_state(QEMUFile *f, const VMStateDescription *vmsd,
                       void *opaque, int version_id)
{
    VMStateField *field = vmsd->fields;
    int ret = 0;

    trace_vmstate_load_state(vmsd->name, version_id);
    if (version_id > vmsd->version_id) {
        trace_vmstate_load_state_end(vmsd->name, "too new", -EINVAL);
        return -EINVAL;
    }
    if  (version_id < vmsd->minimum_version_id) {
        if (vmsd->load_state_old &&
            version_id >= vmsd->minimum_version_id_old) {
            ret = vmsd->load_state_old(f, opaque, version_id);
            trace_vmstate_load_state_end(vmsd->name, "old path", ret);
            return ret;
        }
        trace_vmstate_load_state_end(vmsd->name, "too old", -EINVAL);
        return -EINVAL;
    }
    if (vmsd->pre_load) {
        int ret = vmsd->pre_load(opaque);
        if (ret) {
            return ret;
        }
    }
    while (field->name) {
        trace_vmstate_load_state_field(vmsd->name, field->name);
        if ((field->field_exists &&
             field->field_exists(opaque, version_id)) ||
            (!field->field_exists &&
             field->version_id <= version_id)) {
            void *base_addr = vmstate_base_addr(opaque, field, true);
            int i, n_elems = vmstate_n_elems(opaque, field);
            int size = vmstate_size(opaque, field);

            for (i = 0; i < n_elems; i++) {
                void *addr = base_addr + size * i;

                if (field->flags & VMS_ARRAY_OF_POINTER) {
                    addr = *(void **)addr;
                }
                if (field->flags & VMS_STRUCT) {
                    ret = vmstate_load_state(f, field->vmsd, addr,
                                             field->vmsd->version_id);
                } else {
                    ret = field->info->get(f, addr, size);

                }
                if (ret >= 0) {
                    ret = qemu_file_get_error(f);
                }
                if (ret < 0) {
                    qemu_file_set_error(f, ret);
                    trace_vmstate_load_field_error(field->name, ret);
                    return ret;
                }
            }
        } else if (field->flags & VMS_MUST_EXIST) {
            error_report("Input validation failed: %s/%s",
                         vmsd->name, field->name);
            return -1;
        }
        field++;
    }
    ret = vmstate_subsection_load(f, vmsd, opaque);
    if (ret != 0) {
        return ret;
    }
    if (vmsd->post_load) {
        ret = vmsd->post_load(opaque, version_id);
    }
    trace_vmstate_load_state_end(vmsd->name, "end", ret);
    return ret;
}

static int vmfield_name_num(VMStateField *start, VMStateField *search)
{
    VMStateField *field;
    int found = 0;

    for (field = start; field->name; field++) {
        if (!strcmp(field->name, search->name)) {
            if (field == search) {
                return found;
            }
            found++;
        }
    }

    return -1;
}

static bool vmfield_name_is_unique(VMStateField *start, VMStateField *search)
{
    VMStateField *field;
    int found = 0;

    for (field = start; field->name; field++) {
        if (!strcmp(field->name, search->name)) {
            found++;
            /* name found more than once, so it's not unique */
            if (found > 1) {
                return false;
            }
        }
    }

    return true;
}

static const char *vmfield_get_type_name(VMStateField *field)
{
    const char *type = "unknown";

    if (field->flags & VMS_STRUCT) {
        type = "struct";
    } else if (field->info->name) {
        type = field->info->name;
    }

    return type;
}

static bool vmsd_can_compress(VMStateField *field)
{
    if (field->field_exists) {
        /* Dynamically existing fields mess up compression */
        return false;
    }

    if (field->flags & VMS_STRUCT) {
        VMStateField *sfield = field->vmsd->fields;
        while (sfield->name) {
            if (!vmsd_can_compress(sfield)) {
                /* Child elements can't compress, so can't we */
                return false;
            }
            sfield++;
        }

        if (field->vmsd->subsections) {
            /* Subsections may come and go, better don't compress */
            return false;
        }
    }

    return true;
}

static void vmsd_desc_field_start(const VMStateDescription *vmsd, QJSON *vmdesc,
                                  VMStateField *field, int i, int max)
{
    char *name, *old_name;
    bool is_array = max > 1;
    bool can_compress = vmsd_can_compress(field);

    if (!vmdesc) {
        return;
    }

    name = g_strdup(field->name);

    /* Field name is not unique, need to make it unique */
    if (!vmfield_name_is_unique(vmsd->fields, field)) {
        int num = vmfield_name_num(vmsd->fields, field);
        old_name = name;
        name = g_strdup_printf("%s[%d]", name, num);
        g_free(old_name);
    }

    json_start_object(vmdesc, NULL);
    json_prop_str(vmdesc, "name", name);
    if (is_array) {
        if (can_compress) {
            json_prop_int(vmdesc, "array_len", max);
        } else {
            json_prop_int(vmdesc, "index", i);
        }
    }
    json_prop_str(vmdesc, "type", vmfield_get_type_name(field));

    if (field->flags & VMS_STRUCT) {
        json_start_object(vmdesc, "struct");
    }

    g_free(name);
}

static void vmsd_desc_field_end(const VMStateDescription *vmsd, QJSON *vmdesc,
                                VMStateField *field, size_t size, int i)
{
    if (!vmdesc) {
        return;
    }

    if (field->flags & VMS_STRUCT) {
        /* We printed a struct in between, close its child object */
        json_end_object(vmdesc);
    }

    json_prop_int(vmdesc, "size", size);
    json_end_object(vmdesc);
}


bool vmstate_save_needed(const VMStateDescription *vmsd, void *opaque)
{
    if (vmsd->needed && !vmsd->needed(opaque)) {
        /* optional section not needed */
        return false;
    }
    return true;
}


void vmstate_save_state(QEMUFile *f, const VMStateDescription *vmsd,
                        void *opaque, QJSON *vmdesc)
{
    VMStateField *field = vmsd->fields;

    if (vmsd->pre_save) {
        vmsd->pre_save(opaque);
    }

    if (vmdesc) {
        json_prop_str(vmdesc, "vmsd_name", vmsd->name);
        json_prop_int(vmdesc, "version", vmsd->version_id);
        json_start_array(vmdesc, "fields");
    }

    while (field->name) {
        if (!field->field_exists ||
            field->field_exists(opaque, vmsd->version_id)) {
            void *base_addr = vmstate_base_addr(opaque, field, false);
            int i, n_elems = vmstate_n_elems(opaque, field);
            int size = vmstate_size(opaque, field);
            int64_t old_offset, written_bytes;
            QJSON *vmdesc_loop = vmdesc;

            for (i = 0; i < n_elems; i++) {
                void *addr = base_addr + size * i;

                vmsd_desc_field_start(vmsd, vmdesc_loop, field, i, n_elems);
                old_offset = qemu_ftell_fast(f);

                if (field->flags & VMS_ARRAY_OF_POINTER) {
                    addr = *(void **)addr;
                }
                if (field->flags & VMS_STRUCT) {
                    vmstate_save_state(f, field->vmsd, addr, vmdesc_loop);
                } else {
                    field->info->put(f, addr, size);
                }

                written_bytes = qemu_ftell_fast(f) - old_offset;
                vmsd_desc_field_end(vmsd, vmdesc_loop, field, written_bytes, i);

                /* Compressed arrays only care about the first element */
                if (vmdesc_loop && vmsd_can_compress(field)) {
                    vmdesc_loop = NULL;
                }
            }
        } else {
            if (field->flags & VMS_MUST_EXIST) {
                error_report("Output state validation failed: %s/%s",
                        vmsd->name, field->name);
                assert(!(field->flags & VMS_MUST_EXIST));
            }
        }
        field++;
    }

    if (vmdesc) {
        json_end_array(vmdesc);
    }

    vmstate_subsection_save(f, vmsd, opaque, vmdesc);
}

static const VMStateDescription *
vmstate_get_subsection(const VMStateDescription **sub, char *idstr)
{
    while (sub && *sub && (*sub)->needed) {
        if (strcmp(idstr, (*sub)->name) == 0) {
            return *sub;
        }
        sub++;
    }
    return NULL;
}

static int vmstate_subsection_load(QEMUFile *f, const VMStateDescription *vmsd,
                                   void *opaque)
{
    trace_vmstate_subsection_load(vmsd->name);

    while (qemu_peek_byte(f, 0) == QEMU_VM_SUBSECTION) {
        char idstr[256], *idstr_ret;
        int ret;
        uint8_t version_id, len, size;
        const VMStateDescription *sub_vmsd;

        len = qemu_peek_byte(f, 1);
        if (len < strlen(vmsd->name) + 1) {
            /* subsection name has be be "section_name/a" */
            trace_vmstate_subsection_load_bad(vmsd->name, "(short)");
            return 0;
        }
        size = qemu_peek_buffer(f, (uint8_t **)&idstr_ret, len, 2);
        if (size != len) {
            trace_vmstate_subsection_load_bad(vmsd->name, "(peek fail)");
            return 0;
        }
        memcpy(idstr, idstr_ret, size);
        idstr[size] = 0;

        if (strncmp(vmsd->name, idstr, strlen(vmsd->name)) != 0) {
            trace_vmstate_subsection_load_bad(vmsd->name, idstr);
            /* it don't have a valid subsection name */
            return 0;
        }
        sub_vmsd = vmstate_get_subsection(vmsd->subsections, idstr);
        if (sub_vmsd == NULL) {
            trace_vmstate_subsection_load_bad(vmsd->name, "(lookup)");
            return -ENOENT;
        }
        qemu_file_skip(f, 1); /* subsection */
        qemu_file_skip(f, 1); /* len */
        qemu_file_skip(f, len); /* idstr */
        version_id = qemu_get_be32(f);

        ret = vmstate_load_state(f, sub_vmsd, opaque, version_id);
        if (ret) {
            trace_vmstate_subsection_load_bad(vmsd->name, "(child)");
            return ret;
        }
    }

    trace_vmstate_subsection_load_good(vmsd->name);
    return 0;
}

static void vmstate_subsection_save(QEMUFile *f, const VMStateDescription *vmsd,
                                    void *opaque, QJSON *vmdesc)
{
    const VMStateDescription **sub = vmsd->subsections;
    bool subsection_found = false;

    while (sub && *sub && (*sub)->needed) {
        if ((*sub)->needed(opaque)) {
            const VMStateDescription *vmsd = *sub;
            uint8_t len;

            if (vmdesc) {
                /* Only create subsection array when we have any */
                if (!subsection_found) {
                    json_start_array(vmdesc, "subsections");
                    subsection_found = true;
                }

                json_start_object(vmdesc, NULL);
            }

            qemu_put_byte(f, QEMU_VM_SUBSECTION);
            len = strlen(vmsd->name);
            qemu_put_byte(f, len);
            qemu_put_buffer(f, (uint8_t *)vmsd->name, len);
            qemu_put_be32(f, vmsd->version_id);
            vmstate_save_state(f, vmsd, opaque, vmdesc);

            if (vmdesc) {
                json_end_object(vmdesc);
            }
        }
        sub++;
    }

    if (vmdesc && subsection_found) {
        json_end_array(vmdesc);
    }
}

/* bool */

static int get_bool(QEMUFile *f, void *pv, size_t size)
{
    bool *v = pv;
    *v = qemu_get_byte(f);
    return 0;
}

static void put_bool(QEMUFile *f, void *pv, size_t size)
{
    bool *v = pv;
    qemu_put_byte(f, *v);
}

const VMStateInfo vmstate_info_bool = {
    .name = "bool",
    .get  = get_bool,
    .put  = put_bool,
};

/* 8 bit int */

static int get_int8(QEMUFile *f, void *pv, size_t size)
{
    int8_t *v = pv;
    qemu_get_s8s(f, v);
    return 0;
}

static void put_int8(QEMUFile *f, void *pv, size_t size)
{
    int8_t *v = pv;
    qemu_put_s8s(f, v);
}

const VMStateInfo vmstate_info_int8 = {
    .name = "int8",
    .get  = get_int8,
    .put  = put_int8,
};

/* 16 bit int */

static int get_int16(QEMUFile *f, void *pv, size_t size)
{
    int16_t *v = pv;
    qemu_get_sbe16s(f, v);
    return 0;
}

static void put_int16(QEMUFile *f, void *pv, size_t size)
{
    int16_t *v = pv;
    qemu_put_sbe16s(f, v);
}

const VMStateInfo vmstate_info_int16 = {
    .name = "int16",
    .get  = get_int16,
    .put  = put_int16,
};

/* 32 bit int */

static int get_int32(QEMUFile *f, void *pv, size_t size)
{
    int32_t *v = pv;
    qemu_get_sbe32s(f, v);
    return 0;
}

static void put_int32(QEMUFile *f, void *pv, size_t size)
{
    int32_t *v = pv;
    qemu_put_sbe32s(f, v);
}

const VMStateInfo vmstate_info_int32 = {
    .name = "int32",
    .get  = get_int32,
    .put  = put_int32,
};

/* 32 bit int. See that the received value is the same than the one
   in the field */

static int get_int32_equal(QEMUFile *f, void *pv, size_t size)
{
    int32_t *v = pv;
    int32_t v2;
    qemu_get_sbe32s(f, &v2);

    if (*v == v2) {
        return 0;
    }
    return -EINVAL;
}

const VMStateInfo vmstate_info_int32_equal = {
    .name = "int32 equal",
    .get  = get_int32_equal,
    .put  = put_int32,
};

/* 32 bit int. Check that the received value is non-negative
 * and less than or equal to the one in the field.
 */

static int get_int32_le(QEMUFile *f, void *pv, size_t size)
{
    int32_t *cur = pv;
    int32_t loaded;
    qemu_get_sbe32s(f, &loaded);

    if (loaded >= 0 && loaded <= *cur) {
        *cur = loaded;
        return 0;
    }
    return -EINVAL;
}

const VMStateInfo vmstate_info_int32_le = {
    .name = "int32 le",
    .get  = get_int32_le,
    .put  = put_int32,
};

/* 64 bit int */

static int get_int64(QEMUFile *f, void *pv, size_t size)
{
    int64_t *v = pv;
    qemu_get_sbe64s(f, v);
    return 0;
}

static void put_int64(QEMUFile *f, void *pv, size_t size)
{
    int64_t *v = pv;
    qemu_put_sbe64s(f, v);
}

const VMStateInfo vmstate_info_int64 = {
    .name = "int64",
    .get  = get_int64,
    .put  = put_int64,
};

/* 8 bit unsigned int */

static int get_uint8(QEMUFile *f, void *pv, size_t size)
{
    uint8_t *v = pv;
    qemu_get_8s(f, v);
    return 0;
}

static void put_uint8(QEMUFile *f, void *pv, size_t size)
{
    uint8_t *v = pv;
    qemu_put_8s(f, v);
}

const VMStateInfo vmstate_info_uint8 = {
    .name = "uint8",
    .get  = get_uint8,
    .put  = put_uint8,
};

/* 16 bit unsigned int */

static int get_uint16(QEMUFile *f, void *pv, size_t size)
{
    uint16_t *v = pv;
    qemu_get_be16s(f, v);
    return 0;
}

static void put_uint16(QEMUFile *f, void *pv, size_t size)
{
    uint16_t *v = pv;
    qemu_put_be16s(f, v);
}

const VMStateInfo vmstate_info_uint16 = {
    .name = "uint16",
    .get  = get_uint16,
    .put  = put_uint16,
};

/* 32 bit unsigned int */

static int get_uint32(QEMUFile *f, void *pv, size_t size)
{
    uint32_t *v = pv;
    qemu_get_be32s(f, v);
    return 0;
}

static void put_uint32(QEMUFile *f, void *pv, size_t size)
{
    uint32_t *v = pv;
    qemu_put_be32s(f, v);
}

const VMStateInfo vmstate_info_uint32 = {
    .name = "uint32",
    .get  = get_uint32,
    .put  = put_uint32,
};

/* 32 bit uint. See that the received value is the same than the one
   in the field */

static int get_uint32_equal(QEMUFile *f, void *pv, size_t size)
{
    uint32_t *v = pv;
    uint32_t v2;
    qemu_get_be32s(f, &v2);

    if (*v == v2) {
        return 0;
    }
    return -EINVAL;
}

const VMStateInfo vmstate_info_uint32_equal = {
    .name = "uint32 equal",
    .get  = get_uint32_equal,
    .put  = put_uint32,
};

/* 64 bit unsigned int */

static int get_uint64(QEMUFile *f, void *pv, size_t size)
{
    uint64_t *v = pv;
    qemu_get_be64s(f, v);
    return 0;
}

static void put_uint64(QEMUFile *f, void *pv, size_t size)
{
    uint64_t *v = pv;
    qemu_put_be64s(f, v);
}

const VMStateInfo vmstate_info_uint64 = {
    .name = "uint64",
    .get  = get_uint64,
    .put  = put_uint64,
};

/* 64 bit unsigned int. See that the received value is the same than the one
   in the field */

static int get_uint64_equal(QEMUFile *f, void *pv, size_t size)
{
    uint64_t *v = pv;
    uint64_t v2;
    qemu_get_be64s(f, &v2);

    if (*v == v2) {
        return 0;
    }
    return -EINVAL;
}

const VMStateInfo vmstate_info_uint64_equal = {
    .name = "int64 equal",
    .get  = get_uint64_equal,
    .put  = put_uint64,
};

/* 8 bit int. See that the received value is the same than the one
   in the field */

static int get_uint8_equal(QEMUFile *f, void *pv, size_t size)
{
    uint8_t *v = pv;
    uint8_t v2;
    qemu_get_8s(f, &v2);

    if (*v == v2) {
        return 0;
    }
    return -EINVAL;
}

const VMStateInfo vmstate_info_uint8_equal = {
    .name = "uint8 equal",
    .get  = get_uint8_equal,
    .put  = put_uint8,
};

/* 16 bit unsigned int int. See that the received value is the same than the one
   in the field */

static int get_uint16_equal(QEMUFile *f, void *pv, size_t size)
{
    uint16_t *v = pv;
    uint16_t v2;
    qemu_get_be16s(f, &v2);

    if (*v == v2) {
        return 0;
    }
    return -EINVAL;
}

const VMStateInfo vmstate_info_uint16_equal = {
    .name = "uint16 equal",
    .get  = get_uint16_equal,
    .put  = put_uint16,
};

/* floating point */

static int get_float64(QEMUFile *f, void *pv, size_t size)
{
    float64 *v = pv;

    *v = make_float64(qemu_get_be64(f));
    return 0;
}

static void put_float64(QEMUFile *f, void *pv, size_t size)
{
    uint64_t *v = pv;

    qemu_put_be64(f, float64_val(*v));
}

const VMStateInfo vmstate_info_float64 = {
    .name = "float64",
    .get  = get_float64,
    .put  = put_float64,
};

/* CPU_DoubleU type */

static int get_cpudouble(QEMUFile *f, void *pv, size_t size)
{
    CPU_DoubleU *v = pv;
    qemu_get_be32s(f, &v->l.upper);
    qemu_get_be32s(f, &v->l.lower);
    return 0;
}

static void put_cpudouble(QEMUFile *f, void *pv, size_t size)
{
    CPU_DoubleU *v = pv;
    qemu_put_be32s(f, &v->l.upper);
    qemu_put_be32s(f, &v->l.lower);
}

const VMStateInfo vmstate_info_cpudouble = {
    .name = "CPU_Double_U",
    .get  = get_cpudouble,
    .put  = put_cpudouble,
};

/* uint8_t buffers */

static int get_buffer(QEMUFile *f, void *pv, size_t size)
{
    uint8_t *v = pv;
    qemu_get_buffer(f, v, size);
    return 0;
}

static void put_buffer(QEMUFile *f, void *pv, size_t size)
{
    uint8_t *v = pv;
    qemu_put_buffer(f, v, size);
}

const VMStateInfo vmstate_info_buffer = {
    .name = "buffer",
    .get  = get_buffer,
    .put  = put_buffer,
};

/* unused buffers: space that was used for some fields that are
   not useful anymore */

static int get_unused_buffer(QEMUFile *f, void *pv, size_t size)
{
    uint8_t buf[1024];
    int block_len;

    while (size > 0) {
        block_len = MIN(sizeof(buf), size);
        size -= block_len;
        qemu_get_buffer(f, buf, block_len);
    }
   return 0;
}

static void put_unused_buffer(QEMUFile *f, void *pv, size_t size)
{
    static const uint8_t buf[1024];
    int block_len;

    while (size > 0) {
        block_len = MIN(sizeof(buf), size);
        size -= block_len;
        qemu_put_buffer(f, buf, block_len);
    }
}

const VMStateInfo vmstate_info_unused_buffer = {
    .name = "unused_buffer",
    .get  = get_unused_buffer,
    .put  = put_unused_buffer,
};

/* bitmaps (as defined by bitmap.h). Note that size here is the size
 * of the bitmap in bits. The on-the-wire format of a bitmap is 64
 * bit words with the bits in big endian order. The in-memory format
 * is an array of 'unsigned long', which may be either 32 or 64 bits.
 */
/* This is the number of 64 bit words sent over the wire */
#define BITS_TO_U64S(nr) DIV_ROUND_UP(nr, 64)
static int get_bitmap(QEMUFile *f, void *pv, size_t size)
{
    unsigned long *bmp = pv;
    int i, idx = 0;
    for (i = 0; i < BITS_TO_U64S(size); i++) {
        uint64_t w = qemu_get_be64(f);
        bmp[idx++] = w;
        if (sizeof(unsigned long) == 4 && idx < BITS_TO_LONGS(size)) {
            bmp[idx++] = w >> 32;
        }
    }
    return 0;
}

static void put_bitmap(QEMUFile *f, void *pv, size_t size)
{
    unsigned long *bmp = pv;
    int i, idx = 0;
    for (i = 0; i < BITS_TO_U64S(size); i++) {
        uint64_t w = bmp[idx++];
        if (sizeof(unsigned long) == 4 && idx < BITS_TO_LONGS(size)) {
            w |= ((uint64_t)bmp[idx++]) << 32;
        }
        qemu_put_be64(f, w);
    }
}

const VMStateInfo vmstate_info_bitmap = {
    .name = "bitmap",
    .get = get_bitmap,
    .put = put_bitmap,
};