aboutsummaryrefslogtreecommitdiff
path: root/include/exec/memory.h
blob: d0f35be1c3b14e11e4f54f036db729b3f7ed14dc (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
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
/*
 * Physical memory management API
 *
 * Copyright 2011 Red Hat, Inc. and/or its affiliates
 *
 * Authors:
 *  Avi Kivity <avi@redhat.com>
 *
 * This work is licensed under the terms of the GNU GPL, version 2.  See
 * the COPYING file in the top-level directory.
 *
 */

#ifndef MEMORY_H
#define MEMORY_H

#ifndef CONFIG_USER_ONLY

#include "exec/cpu-common.h"
#include "exec/hwaddr.h"
#include "exec/memattrs.h"
#include "exec/ramlist.h"
#include "qemu/queue.h"
#include "qemu/int128.h"
#include "qemu/notify.h"
#include "qom/object.h"
#include "qemu/rcu.h"
#include "hw/qdev-core.h"

#define RAM_ADDR_INVALID (~(ram_addr_t)0)

#define MAX_PHYS_ADDR_SPACE_BITS 62
#define MAX_PHYS_ADDR            (((hwaddr)1 << MAX_PHYS_ADDR_SPACE_BITS) - 1)

#define TYPE_MEMORY_REGION "qemu:memory-region"
#define MEMORY_REGION(obj) \
        OBJECT_CHECK(MemoryRegion, (obj), TYPE_MEMORY_REGION)

#define TYPE_IOMMU_MEMORY_REGION "qemu:iommu-memory-region"
#define IOMMU_MEMORY_REGION(obj) \
        OBJECT_CHECK(IOMMUMemoryRegion, (obj), TYPE_IOMMU_MEMORY_REGION)
#define IOMMU_MEMORY_REGION_CLASS(klass) \
        OBJECT_CLASS_CHECK(IOMMUMemoryRegionClass, (klass), \
                         TYPE_IOMMU_MEMORY_REGION)
#define IOMMU_MEMORY_REGION_GET_CLASS(obj) \
        OBJECT_GET_CLASS(IOMMUMemoryRegionClass, (obj), \
                         TYPE_IOMMU_MEMORY_REGION)

typedef struct MemoryRegionOps MemoryRegionOps;
typedef struct MemoryRegionMmio MemoryRegionMmio;

struct MemoryRegionMmio {
    CPUReadMemoryFunc *read[3];
    CPUWriteMemoryFunc *write[3];
};

typedef struct IOMMUTLBEntry IOMMUTLBEntry;

/* See address_space_translate: bit 0 is read, bit 1 is write.  */
typedef enum {
    IOMMU_NONE = 0,
    IOMMU_RO   = 1,
    IOMMU_WO   = 2,
    IOMMU_RW   = 3,
} IOMMUAccessFlags;

#define IOMMU_ACCESS_FLAG(r, w) (((r) ? IOMMU_RO : 0) | ((w) ? IOMMU_WO : 0))

struct IOMMUTLBEntry {
    AddressSpace    *target_as;
    hwaddr           iova;
    hwaddr           translated_addr;
    hwaddr           addr_mask;  /* 0xfff = 4k translation */
    IOMMUAccessFlags perm;
};

/*
 * Bitmap for different IOMMUNotifier capabilities. Each notifier can
 * register with one or multiple IOMMU Notifier capability bit(s).
 */
typedef enum {
    IOMMU_NOTIFIER_NONE = 0,
    /* Notify cache invalidations */
    IOMMU_NOTIFIER_UNMAP = 0x1,
    /* Notify entry changes (newly created entries) */
    IOMMU_NOTIFIER_MAP = 0x2,
} IOMMUNotifierFlag;

#define IOMMU_NOTIFIER_ALL (IOMMU_NOTIFIER_MAP | IOMMU_NOTIFIER_UNMAP)

struct IOMMUNotifier;
typedef void (*IOMMUNotify)(struct IOMMUNotifier *notifier,
                            IOMMUTLBEntry *data);

struct IOMMUNotifier {
    IOMMUNotify notify;
    IOMMUNotifierFlag notifier_flags;
    /* Notify for address space range start <= addr <= end */
    hwaddr start;
    hwaddr end;
    int iommu_idx;
    QLIST_ENTRY(IOMMUNotifier) node;
};
typedef struct IOMMUNotifier IOMMUNotifier;

/* RAM is pre-allocated and passed into qemu_ram_alloc_from_ptr */
#define RAM_PREALLOC   (1 << 0)

/* RAM is mmap-ed with MAP_SHARED */
#define RAM_SHARED     (1 << 1)

/* Only a portion of RAM (used_length) is actually used, and migrated.
 * This used_length size can change across reboots.
 */
#define RAM_RESIZEABLE (1 << 2)

/* UFFDIO_ZEROPAGE is available on this RAMBlock to atomically
 * zero the page and wake waiting processes.
 * (Set during postcopy)
 */
#define RAM_UF_ZEROPAGE (1 << 3)

/* RAM can be migrated */
#define RAM_MIGRATABLE (1 << 4)

/* RAM is a persistent kind memory */
#define RAM_PMEM (1 << 5)

static inline void iommu_notifier_init(IOMMUNotifier *n, IOMMUNotify fn,
                                       IOMMUNotifierFlag flags,
                                       hwaddr start, hwaddr end,
                                       int iommu_idx)
{
    n->notify = fn;
    n->notifier_flags = flags;
    n->start = start;
    n->end = end;
    n->iommu_idx = iommu_idx;
}

/*
 * Memory region callbacks
 */
struct MemoryRegionOps {
    /* Read from the memory region. @addr is relative to @mr; @size is
     * in bytes. */
    uint64_t (*read)(void *opaque,
                     hwaddr addr,
                     unsigned size);
    /* Write to the memory region. @addr is relative to @mr; @size is
     * in bytes. */
    void (*write)(void *opaque,
                  hwaddr addr,
                  uint64_t data,
                  unsigned size);

    MemTxResult (*read_with_attrs)(void *opaque,
                                   hwaddr addr,
                                   uint64_t *data,
                                   unsigned size,
                                   MemTxAttrs attrs);
    MemTxResult (*write_with_attrs)(void *opaque,
                                    hwaddr addr,
                                    uint64_t data,
                                    unsigned size,
                                    MemTxAttrs attrs);

    enum device_endian endianness;
    /* Guest-visible constraints: */
    struct {
        /* If nonzero, specify bounds on access sizes beyond which a machine
         * check is thrown.
         */
        unsigned min_access_size;
        unsigned max_access_size;
        /* If true, unaligned accesses are supported.  Otherwise unaligned
         * accesses throw machine checks.
         */
         bool unaligned;
        /*
         * If present, and returns #false, the transaction is not accepted
         * by the device (and results in machine dependent behaviour such
         * as a machine check exception).
         */
        bool (*accepts)(void *opaque, hwaddr addr,
                        unsigned size, bool is_write,
                        MemTxAttrs attrs);
    } valid;
    /* Internal implementation constraints: */
    struct {
        /* If nonzero, specifies the minimum size implemented.  Smaller sizes
         * will be rounded upwards and a partial result will be returned.
         */
        unsigned min_access_size;
        /* If nonzero, specifies the maximum size implemented.  Larger sizes
         * will be done as a series of accesses with smaller sizes.
         */
        unsigned max_access_size;
        /* If true, unaligned accesses are supported.  Otherwise all accesses
         * are converted to (possibly multiple) naturally aligned accesses.
         */
        bool unaligned;
    } impl;
};

enum IOMMUMemoryRegionAttr {
    IOMMU_ATTR_SPAPR_TCE_FD
};

/**
 * struct IOMMUMemoryRegionClass:
 *
 * All IOMMU implementations need to subclass TYPE_IOMMU_MEMORY_REGION
 * and provide an implementation of at least the @translate method here
 * to handle requests to the memory region. Other methods are optional.
 *
 * The IOMMU implementation must use the IOMMU notifier infrastructure
 * to report whenever mappings are changed, by calling
 * memory_region_notify_iommu() (or, if necessary, by calling
 * memory_region_notify_one() for each registered notifier).
 *
 * Conceptually an IOMMU provides a mapping from input address
 * to an output TLB entry. If the IOMMU is aware of memory transaction
 * attributes and the output TLB entry depends on the transaction
 * attributes, we represent this using IOMMU indexes. Each index
 * selects a particular translation table that the IOMMU has:
 *
 * -  @attrs_to_index returns the IOMMU index for a set of transaction attributes
 * -  @translate takes an input address and an IOMMU index
 *
 * and the mapping returned can only depend on the input address and the
 * IOMMU index.
 *
 * Most IOMMUs don't care about the transaction attributes and support
 * only a single IOMMU index. A more complex IOMMU might have one index
 * for secure transactions and one for non-secure transactions.
 */
typedef struct IOMMUMemoryRegionClass {
    /* private */
    struct DeviceClass parent_class;

    /*
     * Return a TLB entry that contains a given address.
     *
     * The IOMMUAccessFlags indicated via @flag are optional and may
     * be specified as IOMMU_NONE to indicate that the caller needs
     * the full translation information for both reads and writes. If
     * the access flags are specified then the IOMMU implementation
     * may use this as an optimization, to stop doing a page table
     * walk as soon as it knows that the requested permissions are not
     * allowed. If IOMMU_NONE is passed then the IOMMU must do the
     * full page table walk and report the permissions in the returned
     * IOMMUTLBEntry. (Note that this implies that an IOMMU may not
     * return different mappings for reads and writes.)
     *
     * The returned information remains valid while the caller is
     * holding the big QEMU lock or is inside an RCU critical section;
     * if the caller wishes to cache the mapping beyond that it must
     * register an IOMMU notifier so it can invalidate its cached
     * information when the IOMMU mapping changes.
     *
     * @iommu: the IOMMUMemoryRegion
     * @hwaddr: address to be translated within the memory region
     * @flag: requested access permissions
     * @iommu_idx: IOMMU index for the translation
     */
    IOMMUTLBEntry (*translate)(IOMMUMemoryRegion *iommu, hwaddr addr,
                               IOMMUAccessFlags flag, int iommu_idx);
    /* Returns minimum supported page size in bytes.
     * If this method is not provided then the minimum is assumed to
     * be TARGET_PAGE_SIZE.
     *
     * @iommu: the IOMMUMemoryRegion
     */
    uint64_t (*get_min_page_size)(IOMMUMemoryRegion *iommu);
    /* Called when IOMMU Notifier flag changes (ie when the set of
     * events which IOMMU users are requesting notification for changes).
     * Optional method -- need not be provided if the IOMMU does not
     * need to know exactly which events must be notified.
     *
     * @iommu: the IOMMUMemoryRegion
     * @old_flags: events which previously needed to be notified
     * @new_flags: events which now need to be notified
     */
    void (*notify_flag_changed)(IOMMUMemoryRegion *iommu,
                                IOMMUNotifierFlag old_flags,
                                IOMMUNotifierFlag new_flags);
    /* Called to handle memory_region_iommu_replay().
     *
     * The default implementation of memory_region_iommu_replay() is to
     * call the IOMMU translate method for every page in the address space
     * with flag == IOMMU_NONE and then call the notifier if translate
     * returns a valid mapping. If this method is implemented then it
     * overrides the default behaviour, and must provide the full semantics
     * of memory_region_iommu_replay(), by calling @notifier for every
     * translation present in the IOMMU.
     *
     * Optional method -- an IOMMU only needs to provide this method
     * if the default is inefficient or produces undesirable side effects.
     *
     * Note: this is not related to record-and-replay functionality.
     */
    void (*replay)(IOMMUMemoryRegion *iommu, IOMMUNotifier *notifier);

    /* Get IOMMU misc attributes. This is an optional method that
     * can be used to allow users of the IOMMU to get implementation-specific
     * information. The IOMMU implements this method to handle calls
     * by IOMMU users to memory_region_iommu_get_attr() by filling in
     * the arbitrary data pointer for any IOMMUMemoryRegionAttr values that
     * the IOMMU supports. If the method is unimplemented then
     * memory_region_iommu_get_attr() will always return -EINVAL.
     *
     * @iommu: the IOMMUMemoryRegion
     * @attr: attribute being queried
     * @data: memory to fill in with the attribute data
     *
     * Returns 0 on success, or a negative errno; in particular
     * returns -EINVAL for unrecognized or unimplemented attribute types.
     */
    int (*get_attr)(IOMMUMemoryRegion *iommu, enum IOMMUMemoryRegionAttr attr,
                    void *data);

    /* Return the IOMMU index to use for a given set of transaction attributes.
     *
     * Optional method: if an IOMMU only supports a single IOMMU index then
     * the default implementation of memory_region_iommu_attrs_to_index()
     * will return 0.
     *
     * The indexes supported by an IOMMU must be contiguous, starting at 0.
     *
     * @iommu: the IOMMUMemoryRegion
     * @attrs: memory transaction attributes
     */
    int (*attrs_to_index)(IOMMUMemoryRegion *iommu, MemTxAttrs attrs);

    /* Return the number of IOMMU indexes this IOMMU supports.
     *
     * Optional method: if this method is not provided, then
     * memory_region_iommu_num_indexes() will return 1, indicating that
     * only a single IOMMU index is supported.
     *
     * @iommu: the IOMMUMemoryRegion
     */
    int (*num_indexes)(IOMMUMemoryRegion *iommu);
} IOMMUMemoryRegionClass;

typedef struct CoalescedMemoryRange CoalescedMemoryRange;
typedef struct MemoryRegionIoeventfd MemoryRegionIoeventfd;

struct MemoryRegion {
    Object parent_obj;

    /* All fields are private - violators will be prosecuted */

    /* The following fields should fit in a cache line */
    bool romd_mode;
    bool ram;
    bool subpage;
    bool readonly; /* For RAM regions */
    bool nonvolatile;
    bool rom_device;
    bool flush_coalesced_mmio;
    bool global_locking;
    uint8_t dirty_log_mask;
    bool is_iommu;
    RAMBlock *ram_block;
    Object *owner;

    const MemoryRegionOps *ops;
    void *opaque;
    MemoryRegion *container;
    Int128 size;
    hwaddr addr;
    void (*destructor)(MemoryRegion *mr);
    uint64_t align;
    bool terminates;
    bool ram_device;
    bool enabled;
    bool warning_printed; /* For reservations */
    uint8_t vga_logging_count;
    MemoryRegion *alias;
    hwaddr alias_offset;
    int32_t priority;
    QTAILQ_HEAD(, MemoryRegion) subregions;
    QTAILQ_ENTRY(MemoryRegion) subregions_link;
    QTAILQ_HEAD(, CoalescedMemoryRange) coalesced;
    const char *name;
    unsigned ioeventfd_nb;
    MemoryRegionIoeventfd *ioeventfds;
};

struct IOMMUMemoryRegion {
    MemoryRegion parent_obj;

    QLIST_HEAD(, IOMMUNotifier) iommu_notify;
    IOMMUNotifierFlag iommu_notify_flags;
};

#define IOMMU_NOTIFIER_FOREACH(n, mr) \
    QLIST_FOREACH((n), &(mr)->iommu_notify, node)

/**
 * struct MemoryListener: callbacks structure for updates to the physical memory map
 *
 * Allows a component to adjust to changes in the guest-visible memory map.
 * Use with memory_listener_register() and memory_listener_unregister().
 */
struct MemoryListener {
    void (*begin)(MemoryListener *listener);
    void (*commit)(MemoryListener *listener);
    void (*region_add)(MemoryListener *listener, MemoryRegionSection *section);
    void (*region_del)(MemoryListener *listener, MemoryRegionSection *section);
    void (*region_nop)(MemoryListener *listener, MemoryRegionSection *section);
    void (*log_start)(MemoryListener *listener, MemoryRegionSection *section,
                      int old, int new);
    void (*log_stop)(MemoryListener *listener, MemoryRegionSection *section,
                     int old, int new);
    void (*log_sync)(MemoryListener *listener, MemoryRegionSection *section);
    void (*log_global_start)(MemoryListener *listener);
    void (*log_global_stop)(MemoryListener *listener);
    void (*eventfd_add)(MemoryListener *listener, MemoryRegionSection *section,
                        bool match_data, uint64_t data, EventNotifier *e);
    void (*eventfd_del)(MemoryListener *listener, MemoryRegionSection *section,
                        bool match_data, uint64_t data, EventNotifier *e);
    void (*coalesced_io_add)(MemoryListener *listener, MemoryRegionSection *section,
                               hwaddr addr, hwaddr len);
    void (*coalesced_io_del)(MemoryListener *listener, MemoryRegionSection *section,
                               hwaddr addr, hwaddr len);
    /* Lower = earlier (during add), later (during del) */
    unsigned priority;
    AddressSpace *address_space;
    QTAILQ_ENTRY(MemoryListener) link;
    QTAILQ_ENTRY(MemoryListener) link_as;
};

/**
 * struct AddressSpace: describes a mapping of addresses to #MemoryRegion objects
 */
struct AddressSpace {
    /* All fields are private. */
    struct rcu_head rcu;
    char *name;
    MemoryRegion *root;

    /* Accessed via RCU.  */
    struct FlatView *current_map;

    int ioeventfd_nb;
    struct MemoryRegionIoeventfd *ioeventfds;
    QTAILQ_HEAD(, MemoryListener) listeners;
    QTAILQ_ENTRY(AddressSpace) address_spaces_link;
};

typedef struct AddressSpaceDispatch AddressSpaceDispatch;
typedef struct FlatRange FlatRange;

/* Flattened global view of current active memory hierarchy.  Kept in sorted
 * order.
 */
struct FlatView {
    struct rcu_head rcu;
    unsigned ref;
    FlatRange *ranges;
    unsigned nr;
    unsigned nr_allocated;
    struct AddressSpaceDispatch *dispatch;
    MemoryRegion *root;
};

static inline FlatView *address_space_to_flatview(AddressSpace *as)
{
    return atomic_rcu_read(&as->current_map);
}


/**
 * struct MemoryRegionSection: describes a fragment of a #MemoryRegion
 *
 * @mr: the region, or %NULL if empty
 * @fv: the flat view of the address space the region is mapped in
 * @offset_within_region: the beginning of the section, relative to @mr's start
 * @size: the size of the section; will not exceed @mr's boundaries
 * @offset_within_address_space: the address of the first byte of the section
 *     relative to the region's address space
 * @readonly: writes to this section are ignored
 * @nonvolatile: this section is non-volatile
 */
struct MemoryRegionSection {
    MemoryRegion *mr;
    FlatView *fv;
    hwaddr offset_within_region;
    Int128 size;
    hwaddr offset_within_address_space;
    bool readonly;
    bool nonvolatile;
};

/**
 * memory_region_init: Initialize a memory region
 *
 * The region typically acts as a container for other memory regions.  Use
 * memory_region_add_subregion() to add subregions.
 *
 * @mr: the #MemoryRegion to be initialized
 * @owner: the object that tracks the region's reference count
 * @name: used for debugging; not visible to the user or ABI
 * @size: size of the region; any subregions beyond this size will be clipped
 */
void memory_region_init(MemoryRegion *mr,
                        struct Object *owner,
                        const char *name,
                        uint64_t size);

/**
 * memory_region_ref: Add 1 to a memory region's reference count
 *
 * Whenever memory regions are accessed outside the BQL, they need to be
 * preserved against hot-unplug.  MemoryRegions actually do not have their
 * own reference count; they piggyback on a QOM object, their "owner".
 * This function adds a reference to the owner.
 *
 * All MemoryRegions must have an owner if they can disappear, even if the
 * device they belong to operates exclusively under the BQL.  This is because
 * the region could be returned at any time by memory_region_find, and this
 * is usually under guest control.
 *
 * @mr: the #MemoryRegion
 */
void memory_region_ref(MemoryRegion *mr);

/**
 * memory_region_unref: Remove 1 to a memory region's reference count
 *
 * Whenever memory regions are accessed outside the BQL, they need to be
 * preserved against hot-unplug.  MemoryRegions actually do not have their
 * own reference count; they piggyback on a QOM object, their "owner".
 * This function removes a reference to the owner and possibly destroys it.
 *
 * @mr: the #MemoryRegion
 */
void memory_region_unref(MemoryRegion *mr);

/**
 * memory_region_init_io: Initialize an I/O memory region.
 *
 * Accesses into the region will cause the callbacks in @ops to be called.
 * if @size is nonzero, subregions will be clipped to @size.
 *
 * @mr: the #MemoryRegion to be initialized.
 * @owner: the object that tracks the region's reference count
 * @ops: a structure containing read and write callbacks to be used when
 *       I/O is performed on the region.
 * @opaque: passed to the read and write callbacks of the @ops structure.
 * @name: used for debugging; not visible to the user or ABI
 * @size: size of the region.
 */
void memory_region_init_io(MemoryRegion *mr,
                           struct Object *owner,
                           const MemoryRegionOps *ops,
                           void *opaque,
                           const char *name,
                           uint64_t size);

/**
 * memory_region_init_ram_nomigrate:  Initialize RAM memory region.  Accesses
 *                                    into the region will modify memory
 *                                    directly.
 *
 * @mr: the #MemoryRegion to be initialized.
 * @owner: the object that tracks the region's reference count
 * @name: Region name, becomes part of RAMBlock name used in migration stream
 *        must be unique within any device
 * @size: size of the region.
 * @errp: pointer to Error*, to store an error if it happens.
 *
 * Note that this function does not do anything to cause the data in the
 * RAM memory region to be migrated; that is the responsibility of the caller.
 */
void memory_region_init_ram_nomigrate(MemoryRegion *mr,
                                      struct Object *owner,
                                      const char *name,
                                      uint64_t size,
                                      Error **errp);

/**
 * memory_region_init_ram_shared_nomigrate:  Initialize RAM memory region.
 *                                           Accesses into the region will
 *                                           modify memory directly.
 *
 * @mr: the #MemoryRegion to be initialized.
 * @owner: the object that tracks the region's reference count
 * @name: Region name, becomes part of RAMBlock name used in migration stream
 *        must be unique within any device
 * @size: size of the region.
 * @share: allow remapping RAM to different addresses
 * @errp: pointer to Error*, to store an error if it happens.
 *
 * Note that this function is similar to memory_region_init_ram_nomigrate.
 * The only difference is part of the RAM region can be remapped.
 */
void memory_region_init_ram_shared_nomigrate(MemoryRegion *mr,
                                             struct Object *owner,
                                             const char *name,
                                             uint64_t size,
                                             bool share,
                                             Error **errp);

/**
 * memory_region_init_resizeable_ram:  Initialize memory region with resizeable
 *                                     RAM.  Accesses into the region will
 *                                     modify memory directly.  Only an initial
 *                                     portion of this RAM is actually used.
 *                                     The used size can change across reboots.
 *
 * @mr: the #MemoryRegion to be initialized.
 * @owner: the object that tracks the region's reference count
 * @name: Region name, becomes part of RAMBlock name used in migration stream
 *        must be unique within any device
 * @size: used size of the region.
 * @max_size: max size of the region.
 * @resized: callback to notify owner about used size change.
 * @errp: pointer to Error*, to store an error if it happens.
 *
 * Note that this function does not do anything to cause the data in the
 * RAM memory region to be migrated; that is the responsibility of the caller.
 */
void memory_region_init_resizeable_ram(MemoryRegion *mr,
                                       struct Object *owner,
                                       const char *name,
                                       uint64_t size,
                                       uint64_t max_size,
                                       void (*resized)(const char*,
                                                       uint64_t length,
                                                       void *host),
                                       Error **errp);
#ifdef CONFIG_POSIX

/**
 * memory_region_init_ram_from_file:  Initialize RAM memory region with a
 *                                    mmap-ed backend.
 *
 * @mr: the #MemoryRegion to be initialized.
 * @owner: the object that tracks the region's reference count
 * @name: Region name, becomes part of RAMBlock name used in migration stream
 *        must be unique within any device
 * @size: size of the region.
 * @align: alignment of the region base address; if 0, the default alignment
 *         (getpagesize()) will be used.
 * @ram_flags: Memory region features:
 *             - RAM_SHARED: memory must be mmaped with the MAP_SHARED flag
 *             - RAM_PMEM: the memory is persistent memory
 *             Other bits are ignored now.
 * @path: the path in which to allocate the RAM.
 * @errp: pointer to Error*, to store an error if it happens.
 *
 * Note that this function does not do anything to cause the data in the
 * RAM memory region to be migrated; that is the responsibility of the caller.
 */
void memory_region_init_ram_from_file(MemoryRegion *mr,
                                      struct Object *owner,
                                      const char *name,
                                      uint64_t size,
                                      uint64_t align,
                                      uint32_t ram_flags,
                                      const char *path,
                                      Error **errp);

/**
 * memory_region_init_ram_from_fd:  Initialize RAM memory region with a
 *                                  mmap-ed backend.
 *
 * @mr: the #MemoryRegion to be initialized.
 * @owner: the object that tracks the region's reference count
 * @name: the name of the region.
 * @size: size of the region.
 * @share: %true if memory must be mmaped with the MAP_SHARED flag
 * @fd: the fd to mmap.
 * @errp: pointer to Error*, to store an error if it happens.
 *
 * Note that this function does not do anything to cause the data in the
 * RAM memory region to be migrated; that is the responsibility of the caller.
 */
void memory_region_init_ram_from_fd(MemoryRegion *mr,
                                    struct Object *owner,
                                    const char *name,
                                    uint64_t size,
                                    bool share,
                                    int fd,
                                    Error **errp);
#endif

/**
 * memory_region_init_ram_ptr:  Initialize RAM memory region from a
 *                              user-provided pointer.  Accesses into the
 *                              region will modify memory directly.
 *
 * @mr: the #MemoryRegion to be initialized.
 * @owner: the object that tracks the region's reference count
 * @name: Region name, becomes part of RAMBlock name used in migration stream
 *        must be unique within any device
 * @size: size of the region.
 * @ptr: memory to be mapped; must contain at least @size bytes.
 *
 * Note that this function does not do anything to cause the data in the
 * RAM memory region to be migrated; that is the responsibility of the caller.
 */
void memory_region_init_ram_ptr(MemoryRegion *mr,
                                struct Object *owner,
                                const char *name,
                                uint64_t size,
                                void *ptr);

/**
 * memory_region_init_ram_device_ptr:  Initialize RAM device memory region from
 *                                     a user-provided pointer.
 *
 * A RAM device represents a mapping to a physical device, such as to a PCI
 * MMIO BAR of an vfio-pci assigned device.  The memory region may be mapped
 * into the VM address space and access to the region will modify memory
 * directly.  However, the memory region should not be included in a memory
 * dump (device may not be enabled/mapped at the time of the dump), and
 * operations incompatible with manipulating MMIO should be avoided.  Replaces
 * skip_dump flag.
 *
 * @mr: the #MemoryRegion to be initialized.
 * @owner: the object that tracks the region's reference count
 * @name: the name of the region.
 * @size: size of the region.
 * @ptr: memory to be mapped; must contain at least @size bytes.
 *
 * Note that this function does not do anything to cause the data in the
 * RAM memory region to be migrated; that is the responsibility of the caller.
 * (For RAM device memory regions, migrating the contents rarely makes sense.)
 */
void memory_region_init_ram_device_ptr(MemoryRegion *mr,
                                       struct Object *owner,
                                       const char *name,
                                       uint64_t size,
                                       void *ptr);

/**
 * memory_region_init_alias: Initialize a memory region that aliases all or a
 *                           part of another memory region.
 *
 * @mr: the #MemoryRegion to be initialized.
 * @owner: the object that tracks the region's reference count
 * @name: used for debugging; not visible to the user or ABI
 * @orig: the region to be referenced; @mr will be equivalent to
 *        @orig between @offset and @offset + @size - 1.
 * @offset: start of the section in @orig to be referenced.
 * @size: size of the region.
 */
void memory_region_init_alias(MemoryRegion *mr,
                              struct Object *owner,
                              const char *name,
                              MemoryRegion *orig,
                              hwaddr offset,
                              uint64_t size);

/**
 * memory_region_init_rom_nomigrate: Initialize a ROM memory region.
 *
 * This has the same effect as calling memory_region_init_ram_nomigrate()
 * and then marking the resulting region read-only with
 * memory_region_set_readonly().
 *
 * Note that this function does not do anything to cause the data in the
 * RAM side of the memory region to be migrated; that is the responsibility
 * of the caller.
 *
 * @mr: the #MemoryRegion to be initialized.
 * @owner: the object that tracks the region's reference count
 * @name: Region name, becomes part of RAMBlock name used in migration stream
 *        must be unique within any device
 * @size: size of the region.
 * @errp: pointer to Error*, to store an error if it happens.
 */
void memory_region_init_rom_nomigrate(MemoryRegion *mr,
                                      struct Object *owner,
                                      const char *name,
                                      uint64_t size,
                                      Error **errp);

/**
 * memory_region_init_rom_device_nomigrate:  Initialize a ROM memory region.
 *                                 Writes are handled via callbacks.
 *
 * Note that this function does not do anything to cause the data in the
 * RAM side of the memory region to be migrated; that is the responsibility
 * of the caller.
 *
 * @mr: the #MemoryRegion to be initialized.
 * @owner: the object that tracks the region's reference count
 * @ops: callbacks for write access handling (must not be NULL).
 * @opaque: passed to the read and write callbacks of the @ops structure.
 * @name: Region name, becomes part of RAMBlock name used in migration stream
 *        must be unique within any device
 * @size: size of the region.
 * @errp: pointer to Error*, to store an error if it happens.
 */
void memory_region_init_rom_device_nomigrate(MemoryRegion *mr,
                                             struct Object *owner,
                                             const MemoryRegionOps *ops,
                                             void *opaque,
                                             const char *name,
                                             uint64_t size,
                                             Error **errp);

/**
 * memory_region_init_iommu: Initialize a memory region of a custom type
 * that translates addresses
 *
 * An IOMMU region translates addresses and forwards accesses to a target
 * memory region.
 *
 * The IOMMU implementation must define a subclass of TYPE_IOMMU_MEMORY_REGION.
 * @_iommu_mr should be a pointer to enough memory for an instance of
 * that subclass, @instance_size is the size of that subclass, and
 * @mrtypename is its name. This function will initialize @_iommu_mr as an
 * instance of the subclass, and its methods will then be called to handle
 * accesses to the memory region. See the documentation of
 * #IOMMUMemoryRegionClass for further details.
 *
 * @_iommu_mr: the #IOMMUMemoryRegion to be initialized
 * @instance_size: the IOMMUMemoryRegion subclass instance size
 * @mrtypename: the type name of the #IOMMUMemoryRegion
 * @owner: the object that tracks the region's reference count
 * @name: used for debugging; not visible to the user or ABI
 * @size: size of the region.
 */
void memory_region_init_iommu(void *_iommu_mr,
                              size_t instance_size,
                              const char *mrtypename,
                              Object *owner,
                              const char *name,
                              uint64_t size);

/**
 * memory_region_init_ram - Initialize RAM memory region.  Accesses into the
 *                          region will modify memory directly.
 *
 * @mr: the #MemoryRegion to be initialized
 * @owner: the object that tracks the region's reference count (must be
 *         TYPE_DEVICE or a subclass of TYPE_DEVICE, or NULL)
 * @name: name of the memory region
 * @size: size of the region in bytes
 * @errp: pointer to Error*, to store an error if it happens.
 *
 * This function allocates RAM for a board model or device, and
 * arranges for it to be migrated (by calling vmstate_register_ram()
 * if @owner is a DeviceState, or vmstate_register_ram_global() if
 * @owner is NULL).
 *
 * TODO: Currently we restrict @owner to being either NULL (for
 * global RAM regions with no owner) or devices, so that we can
 * give the RAM block a unique name for migration purposes.
 * We should lift this restriction and allow arbitrary Objects.
 * If you pass a non-NULL non-device @owner then we will assert.
 */
void memory_region_init_ram(MemoryRegion *mr,
                            struct Object *owner,
                            const char *name,
                            uint64_t size,
                            Error **errp);

/**
 * memory_region_init_rom: Initialize a ROM memory region.
 *
 * This has the same effect as calling memory_region_init_ram()
 * and then marking the resulting region read-only with
 * memory_region_set_readonly(). This includes arranging for the
 * contents to be migrated.
 *
 * TODO: Currently we restrict @owner to being either NULL (for
 * global RAM regions with no owner) or devices, so that we can
 * give the RAM block a unique name for migration purposes.
 * We should lift this restriction and allow arbitrary Objects.
 * If you pass a non-NULL non-device @owner then we will assert.
 *
 * @mr: the #MemoryRegion to be initialized.
 * @owner: the object that tracks the region's reference count
 * @name: Region name, becomes part of RAMBlock name used in migration stream
 *        must be unique within any device
 * @size: size of the region.
 * @errp: pointer to Error*, to store an error if it happens.
 */
void memory_region_init_rom(MemoryRegion *mr,
                            struct Object *owner,
                            const char *name,
                            uint64_t size,
                            Error **errp);

/**
 * memory_region_init_rom_device:  Initialize a ROM memory region.
 *                                 Writes are handled via callbacks.
 *
 * This function initializes a memory region backed by RAM for reads
 * and callbacks for writes, and arranges for the RAM backing to
 * be migrated (by calling vmstate_register_ram()
 * if @owner is a DeviceState, or vmstate_register_ram_global() if
 * @owner is NULL).
 *
 * TODO: Currently we restrict @owner to being either NULL (for
 * global RAM regions with no owner) or devices, so that we can
 * give the RAM block a unique name for migration purposes.
 * We should lift this restriction and allow arbitrary Objects.
 * If you pass a non-NULL non-device @owner then we will assert.
 *
 * @mr: the #MemoryRegion to be initialized.
 * @owner: the object that tracks the region's reference count
 * @ops: callbacks for write access handling (must not be NULL).
 * @opaque: passed to the read and write callbacks of the @ops structure.
 * @name: Region name, becomes part of RAMBlock name used in migration stream
 *        must be unique within any device
 * @size: size of the region.
 * @errp: pointer to Error*, to store an error if it happens.
 */
void memory_region_init_rom_device(MemoryRegion *mr,
                                   struct Object *owner,
                                   const MemoryRegionOps *ops,
                                   void *opaque,
                                   const char *name,
                                   uint64_t size,
                                   Error **errp);


/**
 * memory_region_owner: get a memory region's owner.
 *
 * @mr: the memory region being queried.
 */
struct Object *memory_region_owner(MemoryRegion *mr);

/**
 * memory_region_size: get a memory region's size.
 *
 * @mr: the memory region being queried.
 */
uint64_t memory_region_size(MemoryRegion *mr);

/**
 * memory_region_is_ram: check whether a memory region is random access
 *
 * Returns %true if a memory region is random access.
 *
 * @mr: the memory region being queried
 */
static inline bool memory_region_is_ram(MemoryRegion *mr)
{
    return mr->ram;
}

/**
 * memory_region_is_ram_device: check whether a memory region is a ram device
 *
 * Returns %true if a memory region is a device backed ram region
 *
 * @mr: the memory region being queried
 */
bool memory_region_is_ram_device(MemoryRegion *mr);

/**
 * memory_region_is_romd: check whether a memory region is in ROMD mode
 *
 * Returns %true if a memory region is a ROM device and currently set to allow
 * direct reads.
 *
 * @mr: the memory region being queried
 */
static inline bool memory_region_is_romd(MemoryRegion *mr)
{
    return mr->rom_device && mr->romd_mode;
}

/**
 * memory_region_get_iommu: check whether a memory region is an iommu
 *
 * Returns pointer to IOMMUMemoryRegion if a memory region is an iommu,
 * otherwise NULL.
 *
 * @mr: the memory region being queried
 */
static inline IOMMUMemoryRegion *memory_region_get_iommu(MemoryRegion *mr)
{
    if (mr->alias) {
        return memory_region_get_iommu(mr->alias);
    }
    if (mr->is_iommu) {
        return (IOMMUMemoryRegion *) mr;
    }
    return NULL;
}

/**
 * memory_region_get_iommu_class_nocheck: returns iommu memory region class
 *   if an iommu or NULL if not
 *
 * Returns pointer to IOMMUMemoryRegionClass if a memory region is an iommu,
 * otherwise NULL. This is fast path avoiding QOM checking, use with caution.
 *
 * @iommu_mr: the memory region being queried
 */
static inline IOMMUMemoryRegionClass *memory_region_get_iommu_class_nocheck(
        IOMMUMemoryRegion *iommu_mr)
{
    return (IOMMUMemoryRegionClass *) (((Object *)iommu_mr)->class);
}

#define memory_region_is_iommu(mr) (memory_region_get_iommu(mr) != NULL)

/**
 * memory_region_iommu_get_min_page_size: get minimum supported page size
 * for an iommu
 *
 * Returns minimum supported page size for an iommu.
 *
 * @iommu_mr: the memory region being queried
 */
uint64_t memory_region_iommu_get_min_page_size(IOMMUMemoryRegion *iommu_mr);

/**
 * memory_region_notify_iommu: notify a change in an IOMMU translation entry.
 *
 * The notification type will be decided by entry.perm bits:
 *
 * - For UNMAP (cache invalidation) notifies: set entry.perm to IOMMU_NONE.
 * - For MAP (newly added entry) notifies: set entry.perm to the
 *   permission of the page (which is definitely !IOMMU_NONE).
 *
 * Note: for any IOMMU implementation, an in-place mapping change
 * should be notified with an UNMAP followed by a MAP.
 *
 * @iommu_mr: the memory region that was changed
 * @iommu_idx: the IOMMU index for the translation table which has changed
 * @entry: the new entry in the IOMMU translation table.  The entry
 *         replaces all old entries for the same virtual I/O address range.
 *         Deleted entries have .@perm == 0.
 */
void memory_region_notify_iommu(IOMMUMemoryRegion *iommu_mr,
                                int iommu_idx,
                                IOMMUTLBEntry entry);

/**
 * memory_region_notify_one: notify a change in an IOMMU translation
 *                           entry to a single notifier
 *
 * This works just like memory_region_notify_iommu(), but it only
 * notifies a specific notifier, not all of them.
 *
 * @notifier: the notifier to be notified
 * @entry: the new entry in the IOMMU translation table.  The entry
 *         replaces all old entries for the same virtual I/O address range.
 *         Deleted entries have .@perm == 0.
 */
void memory_region_notify_one(IOMMUNotifier *notifier,
                              IOMMUTLBEntry *entry);

/**
 * memory_region_register_iommu_notifier: register a notifier for changes to
 * IOMMU translation entries.
 *
 * @mr: the memory region to observe
 * @n: the IOMMUNotifier to be added; the notify callback receives a
 *     pointer to an #IOMMUTLBEntry as the opaque value; the pointer
 *     ceases to be valid on exit from the notifier.
 */
void memory_region_register_iommu_notifier(MemoryRegion *mr,
                                           IOMMUNotifier *n);

/**
 * memory_region_iommu_replay: replay existing IOMMU translations to
 * a notifier with the minimum page granularity returned by
 * mr->iommu_ops->get_page_size().
 *
 * Note: this is not related to record-and-replay functionality.
 *
 * @iommu_mr: the memory region to observe
 * @n: the notifier to which to replay iommu mappings
 */
void memory_region_iommu_replay(IOMMUMemoryRegion *iommu_mr, IOMMUNotifier *n);

/**
 * memory_region_iommu_replay_all: replay existing IOMMU translations
 * to all the notifiers registered.
 *
 * Note: this is not related to record-and-replay functionality.
 *
 * @iommu_mr: the memory region to observe
 */
void memory_region_iommu_replay_all(IOMMUMemoryRegion *iommu_mr);

/**
 * memory_region_unregister_iommu_notifier: unregister a notifier for
 * changes to IOMMU translation entries.
 *
 * @mr: the memory region which was observed and for which notity_stopped()
 *      needs to be called
 * @n: the notifier to be removed.
 */
void memory_region_unregister_iommu_notifier(MemoryRegion *mr,
                                             IOMMUNotifier *n);

/**
 * memory_region_iommu_get_attr: return an IOMMU attr if get_attr() is
 * defined on the IOMMU.
 *
 * Returns 0 on success, or a negative errno otherwise. In particular,
 * -EINVAL indicates that the IOMMU does not support the requested
 * attribute.
 *
 * @iommu_mr: the memory region
 * @attr: the requested attribute
 * @data: a pointer to the requested attribute data
 */
int memory_region_iommu_get_attr(IOMMUMemoryRegion *iommu_mr,
                                 enum IOMMUMemoryRegionAttr attr,
                                 void *data);

/**
 * memory_region_iommu_attrs_to_index: return the IOMMU index to
 * use for translations with the given memory transaction attributes.
 *
 * @iommu_mr: the memory region
 * @attrs: the memory transaction attributes
 */
int memory_region_iommu_attrs_to_index(IOMMUMemoryRegion *iommu_mr,
                                       MemTxAttrs attrs);

/**
 * memory_region_iommu_num_indexes: return the total number of IOMMU
 * indexes that this IOMMU supports.
 *
 * @iommu_mr: the memory region
 */
int memory_region_iommu_num_indexes(IOMMUMemoryRegion *iommu_mr);

/**
 * memory_region_name: get a memory region's name
 *
 * Returns the string that was used to initialize the memory region.
 *
 * @mr: the memory region being queried
 */
const char *memory_region_name(const MemoryRegion *mr);

/**
 * memory_region_is_logging: return whether a memory region is logging writes
 *
 * Returns %true if the memory region is logging writes for the given client
 *
 * @mr: the memory region being queried
 * @client: the client being queried
 */
bool memory_region_is_logging(MemoryRegion *mr, uint8_t client);

/**
 * memory_region_get_dirty_log_mask: return the clients for which a
 * memory region is logging writes.
 *
 * Returns a bitmap of clients, in which the DIRTY_MEMORY_* constants
 * are the bit indices.
 *
 * @mr: the memory region being queried
 */
uint8_t memory_region_get_dirty_log_mask(MemoryRegion *mr);

/**
 * memory_region_is_rom: check whether a memory region is ROM
 *
 * Returns %true if a memory region is read-only memory.
 *
 * @mr: the memory region being queried
 */
static inline bool memory_region_is_rom(MemoryRegion *mr)
{
    return mr->ram && mr->readonly;
}

/**
 * memory_region_is_nonvolatile: check whether a memory region is non-volatile
 *
 * Returns %true is a memory region is non-volatile memory.
 *
 * @mr: the memory region being queried
 */
static inline bool memory_region_is_nonvolatile(MemoryRegion *mr)
{
    return mr->nonvolatile;
}

/**
 * memory_region_get_fd: Get a file descriptor backing a RAM memory region.
 *
 * Returns a file descriptor backing a file-based RAM memory region,
 * or -1 if the region is not a file-based RAM memory region.
 *
 * @mr: the RAM or alias memory region being queried.
 */
int memory_region_get_fd(MemoryRegion *mr);

/**
 * memory_region_from_host: Convert a pointer into a RAM memory region
 * and an offset within it.
 *
 * Given a host pointer inside a RAM memory region (created with
 * memory_region_init_ram() or memory_region_init_ram_ptr()), return
 * the MemoryRegion and the offset within it.
 *
 * Use with care; by the time this function returns, the returned pointer is
 * not protected by RCU anymore.  If the caller is not within an RCU critical
 * section and does not hold the iothread lock, it must have other means of
 * protecting the pointer, such as a reference to the region that includes
 * the incoming ram_addr_t.
 *
 * @ptr: the host pointer to be converted
 * @offset: the offset within memory region
 */
MemoryRegion *memory_region_from_host(void *ptr, ram_addr_t *offset);

/**
 * memory_region_get_ram_ptr: Get a pointer into a RAM memory region.
 *
 * Returns a host pointer to a RAM memory region (created with
 * memory_region_init_ram() or memory_region_init_ram_ptr()).
 *
 * Use with care; by the time this function returns, the returned pointer is
 * not protected by RCU anymore.  If the caller is not within an RCU critical
 * section and does not hold the iothread lock, it must have other means of
 * protecting the pointer, such as a reference to the region that includes
 * the incoming ram_addr_t.
 *
 * @mr: the memory region being queried.
 */
void *memory_region_get_ram_ptr(MemoryRegion *mr);

/* memory_region_ram_resize: Resize a RAM region.
 *
 * Only legal before guest might have detected the memory size: e.g. on
 * incoming migration, or right after reset.
 *
 * @mr: a memory region created with @memory_region_init_resizeable_ram.
 * @newsize: the new size the region
 * @errp: pointer to Error*, to store an error if it happens.
 */
void memory_region_ram_resize(MemoryRegion *mr, ram_addr_t newsize,
                              Error **errp);

/**
 * memory_region_set_log: Turn dirty logging on or off for a region.
 *
 * Turns dirty logging on or off for a specified client (display, migration).
 * Only meaningful for RAM regions.
 *
 * @mr: the memory region being updated.
 * @log: whether dirty logging is to be enabled or disabled.
 * @client: the user of the logging information; %DIRTY_MEMORY_VGA only.
 */
void memory_region_set_log(MemoryRegion *mr, bool log, unsigned client);

/**
 * memory_region_get_dirty: Check whether a range of bytes is dirty
 *                          for a specified client.
 *
 * Checks whether a range of bytes has been written to since the last
 * call to memory_region_reset_dirty() with the same @client.  Dirty logging
 * must be enabled.
 *
 * @mr: the memory region being queried.
 * @addr: the address (relative to the start of the region) being queried.
 * @size: the size of the range being queried.
 * @client: the user of the logging information; %DIRTY_MEMORY_MIGRATION or
 *          %DIRTY_MEMORY_VGA.
 */
bool memory_region_get_dirty(MemoryRegion *mr, hwaddr addr,
                             hwaddr size, unsigned client);

/**
 * memory_region_set_dirty: Mark a range of bytes as dirty in a memory region.
 *
 * Marks a range of bytes as dirty, after it has been dirtied outside
 * guest code.
 *
 * @mr: the memory region being dirtied.
 * @addr: the address (relative to the start of the region) being dirtied.
 * @size: size of the range being dirtied.
 */
void memory_region_set_dirty(MemoryRegion *mr, hwaddr addr,
                             hwaddr size);

/**
 * memory_region_snapshot_and_clear_dirty: Get a snapshot of the dirty
 *                                         bitmap and clear it.
 *
 * Creates a snapshot of the dirty bitmap, clears the dirty bitmap and
 * returns the snapshot.  The snapshot can then be used to query dirty
 * status, using memory_region_snapshot_get_dirty.  Snapshotting allows
 * querying the same page multiple times, which is especially useful for
 * display updates where the scanlines often are not page aligned.
 *
 * The dirty bitmap region which gets copyed into the snapshot (and
 * cleared afterwards) can be larger than requested.  The boundaries
 * are rounded up/down so complete bitmap longs (covering 64 pages on
 * 64bit hosts) can be copied over into the bitmap snapshot.  Which
 * isn't a problem for display updates as the extra pages are outside
 * the visible area, and in case the visible area changes a full
 * display redraw is due anyway.  Should other use cases for this
 * function emerge we might have to revisit this implementation
 * detail.
 *
 * Use g_free to release DirtyBitmapSnapshot.
 *
 * @mr: the memory region being queried.
 * @addr: the address (relative to the start of the region) being queried.
 * @size: the size of the range being queried.
 * @client: the user of the logging information; typically %DIRTY_MEMORY_VGA.
 */
DirtyBitmapSnapshot *memory_region_snapshot_and_clear_dirty(MemoryRegion *mr,
                                                            hwaddr addr,
                                                            hwaddr size,
                                                            unsigned client);

/**
 * memory_region_snapshot_get_dirty: Check whether a range of bytes is dirty
 *                                   in the specified dirty bitmap snapshot.
 *
 * @mr: the memory region being queried.
 * @snap: the dirty bitmap snapshot
 * @addr: the address (relative to the start of the region) being queried.
 * @size: the size of the range being queried.
 */
bool memory_region_snapshot_get_dirty(MemoryRegion *mr,
                                      DirtyBitmapSnapshot *snap,
                                      hwaddr addr, hwaddr size);

/**
 * memory_region_reset_dirty: Mark a range of pages as clean, for a specified
 *                            client.
 *
 * Marks a range of pages as no longer dirty.
 *
 * @mr: the region being updated.
 * @addr: the start of the subrange being cleaned.
 * @size: the size of the subrange being cleaned.
 * @client: the user of the logging information; %DIRTY_MEMORY_MIGRATION or
 *          %DIRTY_MEMORY_VGA.
 */
void memory_region_reset_dirty(MemoryRegion *mr, hwaddr addr,
                               hwaddr size, unsigned client);

/**
 * memory_region_flush_rom_device: Mark a range of pages dirty and invalidate
 *                                 TBs (for self-modifying code).
 *
 * The MemoryRegionOps->write() callback of a ROM device must use this function
 * to mark byte ranges that have been modified internally, such as by directly
 * accessing the memory returned by memory_region_get_ram_ptr().
 *
 * This function marks the range dirty and invalidates TBs so that TCG can
 * detect self-modifying code.
 *
 * @mr: the region being flushed.
 * @addr: the start, relative to the start of the region, of the range being
 *        flushed.
 * @size: the size, in bytes, of the range being flushed.
 */
void memory_region_flush_rom_device(MemoryRegion *mr, hwaddr addr, hwaddr size);

/**
 * memory_region_set_readonly: Turn a memory region read-only (or read-write)
 *
 * Allows a memory region to be marked as read-only (turning it into a ROM).
 * only useful on RAM regions.
 *
 * @mr: the region being updated.
 * @readonly: whether rhe region is to be ROM or RAM.
 */
void memory_region_set_readonly(MemoryRegion *mr, bool readonly);

/**
 * memory_region_set_nonvolatile: Turn a memory region non-volatile
 *
 * Allows a memory region to be marked as non-volatile.
 * only useful on RAM regions.
 *
 * @mr: the region being updated.
 * @nonvolatile: whether rhe region is to be non-volatile.
 */
void memory_region_set_nonvolatile(MemoryRegion *mr, bool nonvolatile);

/**
 * memory_region_rom_device_set_romd: enable/disable ROMD mode
 *
 * Allows a ROM device (initialized with memory_region_init_rom_device() to
 * set to ROMD mode (default) or MMIO mode.  When it is in ROMD mode, the
 * device is mapped to guest memory and satisfies read access directly.
 * When in MMIO mode, reads are forwarded to the #MemoryRegion.read function.
 * Writes are always handled by the #MemoryRegion.write function.
 *
 * @mr: the memory region to be updated
 * @romd_mode: %true to put the region into ROMD mode
 */
void memory_region_rom_device_set_romd(MemoryRegion *mr, bool romd_mode);

/**
 * memory_region_set_coalescing: Enable memory coalescing for the region.
 *
 * Enabled writes to a region to be queued for later processing. MMIO ->write
 * callbacks may be delayed until a non-coalesced MMIO is issued.
 * Only useful for IO regions.  Roughly similar to write-combining hardware.
 *
 * @mr: the memory region to be write coalesced
 */
void memory_region_set_coalescing(MemoryRegion *mr);

/**
 * memory_region_add_coalescing: Enable memory coalescing for a sub-range of
 *                               a region.
 *
 * Like memory_region_set_coalescing(), but works on a sub-range of a region.
 * Multiple calls can be issued coalesced disjoint ranges.
 *
 * @mr: the memory region to be updated.
 * @offset: the start of the range within the region to be coalesced.
 * @size: the size of the subrange to be coalesced.
 */
void memory_region_add_coalescing(MemoryRegion *mr,
                                  hwaddr offset,
                                  uint64_t size);

/**
 * memory_region_clear_coalescing: Disable MMIO coalescing for the region.
 *
 * Disables any coalescing caused by memory_region_set_coalescing() or
 * memory_region_add_coalescing().  Roughly equivalent to uncacheble memory
 * hardware.
 *
 * @mr: the memory region to be updated.
 */
void memory_region_clear_coalescing(MemoryRegion *mr);

/**
 * memory_region_set_flush_coalesced: Enforce memory coalescing flush before
 *                                    accesses.
 *
 * Ensure that pending coalesced MMIO request are flushed before the memory
 * region is accessed. This property is automatically enabled for all regions
 * passed to memory_region_set_coalescing() and memory_region_add_coalescing().
 *
 * @mr: the memory region to be updated.
 */
void memory_region_set_flush_coalesced(MemoryRegion *mr);

/**
 * memory_region_clear_flush_coalesced: Disable memory coalescing flush before
 *                                      accesses.
 *
 * Clear the automatic coalesced MMIO flushing enabled via
 * memory_region_set_flush_coalesced. Note that this service has no effect on
 * memory regions that have MMIO coalescing enabled for themselves. For them,
 * automatic flushing will stop once coalescing is disabled.
 *
 * @mr: the memory region to be updated.
 */
void memory_region_clear_flush_coalesced(MemoryRegion *mr);

/**
 * memory_region_clear_global_locking: Declares that access processing does
 *                                     not depend on the QEMU global lock.
 *
 * By clearing this property, accesses to the memory region will be processed
 * outside of QEMU's global lock (unless the lock is held on when issuing the
 * access request). In this case, the device model implementing the access
 * handlers is responsible for synchronization of concurrency.
 *
 * @mr: the memory region to be updated.
 */
void memory_region_clear_global_locking(MemoryRegion *mr);

/**
 * memory_region_add_eventfd: Request an eventfd to be triggered when a word
 *                            is written to a location.
 *
 * Marks a word in an IO region (initialized with memory_region_init_io())
 * as a trigger for an eventfd event.  The I/O callback will not be called.
 * The caller must be prepared to handle failure (that is, take the required
 * action if the callback _is_ called).
 *
 * @mr: the memory region being updated.
 * @addr: the address within @mr that is to be monitored
 * @size: the size of the access to trigger the eventfd
 * @match_data: whether to match against @data, instead of just @addr
 * @data: the data to match against the guest write
 * @e: event notifier to be triggered when @addr, @size, and @data all match.
 **/
void memory_region_add_eventfd(MemoryRegion *mr,
                               hwaddr addr,
                               unsigned size,
                               bool match_data,
                               uint64_t data,
                               EventNotifier *e);

/**
 * memory_region_del_eventfd: Cancel an eventfd.
 *
 * Cancels an eventfd trigger requested by a previous
 * memory_region_add_eventfd() call.
 *
 * @mr: the memory region being updated.
 * @addr: the address within @mr that is to be monitored
 * @size: the size of the access to trigger the eventfd
 * @match_data: whether to match against @data, instead of just @addr
 * @data: the data to match against the guest write
 * @e: event notifier to be triggered when @addr, @size, and @data all match.
 */
void memory_region_del_eventfd(MemoryRegion *mr,
                               hwaddr addr,
                               unsigned size,
                               bool match_data,
                               uint64_t data,
                               EventNotifier *e);

/**
 * memory_region_add_subregion: Add a subregion to a container.
 *
 * Adds a subregion at @offset.  The subregion may not overlap with other
 * subregions (except for those explicitly marked as overlapping).  A region
 * may only be added once as a subregion (unless removed with
 * memory_region_del_subregion()); use memory_region_init_alias() if you
 * want a region to be a subregion in multiple locations.
 *
 * @mr: the region to contain the new subregion; must be a container
 *      initialized with memory_region_init().
 * @offset: the offset relative to @mr where @subregion is added.
 * @subregion: the subregion to be added.
 */
void memory_region_add_subregion(MemoryRegion *mr,
                                 hwaddr offset,
                                 MemoryRegion *subregion);
/**
 * memory_region_add_subregion_overlap: Add a subregion to a container
 *                                      with overlap.
 *
 * Adds a subregion at @offset.  The subregion may overlap with other
 * subregions.  Conflicts are resolved by having a higher @priority hide a
 * lower @priority. Subregions without priority are taken as @priority 0.
 * A region may only be added once as a subregion (unless removed with
 * memory_region_del_subregion()); use memory_region_init_alias() if you
 * want a region to be a subregion in multiple locations.
 *
 * @mr: the region to contain the new subregion; must be a container
 *      initialized with memory_region_init().
 * @offset: the offset relative to @mr where @subregion is added.
 * @subregion: the subregion to be added.
 * @priority: used for resolving overlaps; highest priority wins.
 */
void memory_region_add_subregion_overlap(MemoryRegion *mr,
                                         hwaddr offset,
                                         MemoryRegion *subregion,
                                         int priority);

/**
 * memory_region_get_ram_addr: Get the ram address associated with a memory
 *                             region
 * @mr: the memory region to get the ram address for
 */
ram_addr_t memory_region_get_ram_addr(MemoryRegion *mr);

uint64_t memory_region_get_alignment(const MemoryRegion *mr);
/**
 * memory_region_del_subregion: Remove a subregion.
 *
 * Removes a subregion from its container.
 *
 * @mr: the container to be updated.
 * @subregion: the region being removed; must be a current subregion of @mr.
 */
void memory_region_del_subregion(MemoryRegion *mr,
                                 MemoryRegion *subregion);

/*
 * memory_region_set_enabled: dynamically enable or disable a region
 *
 * Enables or disables a memory region.  A disabled memory region
 * ignores all accesses to itself and its subregions.  It does not
 * obscure sibling subregions with lower priority - it simply behaves as
 * if it was removed from the hierarchy.
 *
 * Regions default to being enabled.
 *
 * @mr: the region to be updated
 * @enabled: whether to enable or disable the region
 */
void memory_region_set_enabled(MemoryRegion *mr, bool enabled);

/*
 * memory_region_set_address: dynamically update the address of a region
 *
 * Dynamically updates the address of a region, relative to its container.
 * May be used on regions are currently part of a memory hierarchy.
 *
 * @mr: the region to be updated
 * @addr: new address, relative to container region
 */
void memory_region_set_address(MemoryRegion *mr, hwaddr addr);

/*
 * memory_region_set_size: dynamically update the size of a region.
 *
 * Dynamically updates the size of a region.
 *
 * @mr: the region to be updated
 * @size: used size of the region.
 */
void memory_region_set_size(MemoryRegion *mr, uint64_t size);

/*
 * memory_region_set_alias_offset: dynamically update a memory alias's offset
 *
 * Dynamically updates the offset into the target region that an alias points
 * to, as if the fourth argument to memory_region_init_alias() has changed.
 *
 * @mr: the #MemoryRegion to be updated; should be an alias.
 * @offset: the new offset into the target memory region
 */
void memory_region_set_alias_offset(MemoryRegion *mr,
                                    hwaddr offset);

/**
 * memory_region_present: checks if an address relative to a @container
 * translates into #MemoryRegion within @container
 *
 * Answer whether a #MemoryRegion within @container covers the address
 * @addr.
 *
 * @container: a #MemoryRegion within which @addr is a relative address
 * @addr: the area within @container to be searched
 */
bool memory_region_present(MemoryRegion *container, hwaddr addr);

/**
 * memory_region_is_mapped: returns true if #MemoryRegion is mapped
 * into any address space.
 *
 * @mr: a #MemoryRegion which should be checked if it's mapped
 */
bool memory_region_is_mapped(MemoryRegion *mr);

/**
 * memory_region_find: translate an address/size relative to a
 * MemoryRegion into a #MemoryRegionSection.
 *
 * Locates the first #MemoryRegion within @mr that overlaps the range
 * given by @addr and @size.
 *
 * Returns a #MemoryRegionSection that describes a contiguous overlap.
 * It will have the following characteristics:
 *
 * -   .@size = 0 iff no overlap was found
 * -   .@mr is non-%NULL iff an overlap was found
 *
 * Remember that in the return value the @offset_within_region is
 * relative to the returned region (in the .@mr field), not to the
 * @mr argument.
 *
 * Similarly, the @.offset_within_address_space is relative to the
 * address space that contains both regions, the passed and the
 * returned one.  However, in the special case where the @mr argument
 * has no container (and thus is the root of the address space), the
 * following will hold:
 *
 * -   .@offset_within_address_space >= @addr
 * -   .@offset_within_address_space + .@size <= @addr + @size
 *
 * @mr: a MemoryRegion within which @addr is a relative address
 * @addr: start of the area within @as to be searched
 * @size: size of the area to be searched
 */
MemoryRegionSection memory_region_find(MemoryRegion *mr,
                                       hwaddr addr, uint64_t size);

/**
 * memory_global_dirty_log_sync: synchronize the dirty log for all memory
 *
 * Synchronizes the dirty page log for all address spaces.
 */
void memory_global_dirty_log_sync(void);

/**
 * memory_region_transaction_begin: Start a transaction.
 *
 * During a transaction, changes will be accumulated and made visible
 * only when the transaction ends (is committed).
 */
void memory_region_transaction_begin(void);

/**
 * memory_region_transaction_commit: Commit a transaction and make changes
 *                                   visible to the guest.
 */
void memory_region_transaction_commit(void);

/**
 * memory_listener_register: register callbacks to be called when memory
 *                           sections are mapped or unmapped into an address
 *                           space
 *
 * @listener: an object containing the callbacks to be called
 * @filter: if non-%NULL, only regions in this address space will be observed
 */
void memory_listener_register(MemoryListener *listener, AddressSpace *filter);

/**
 * memory_listener_unregister: undo the effect of memory_listener_register()
 *
 * @listener: an object containing the callbacks to be removed
 */
void memory_listener_unregister(MemoryListener *listener);

/**
 * memory_global_dirty_log_start: begin dirty logging for all regions
 */
void memory_global_dirty_log_start(void);

/**
 * memory_global_dirty_log_stop: end dirty logging for all regions
 */
void memory_global_dirty_log_stop(void);

void mtree_info(bool flatview, bool dispatch_tree, bool owner);

/**
 * memory_region_dispatch_read: perform a read directly to the specified
 * MemoryRegion.
 *
 * @mr: #MemoryRegion to access
 * @addr: address within that region
 * @pval: pointer to uint64_t which the data is written to
 * @size: size of the access in bytes
 * @attrs: memory transaction attributes to use for the access
 */
MemTxResult memory_region_dispatch_read(MemoryRegion *mr,
                                        hwaddr addr,
                                        uint64_t *pval,
                                        unsigned size,
                                        MemTxAttrs attrs);
/**
 * memory_region_dispatch_write: perform a write directly to the specified
 * MemoryRegion.
 *
 * @mr: #MemoryRegion to access
 * @addr: address within that region
 * @data: data to write
 * @size: size of the access in bytes
 * @attrs: memory transaction attributes to use for the access
 */
MemTxResult memory_region_dispatch_write(MemoryRegion *mr,
                                         hwaddr addr,
                                         uint64_t data,
                                         unsigned size,
                                         MemTxAttrs attrs);

/**
 * address_space_init: initializes an address space
 *
 * @as: an uninitialized #AddressSpace
 * @root: a #MemoryRegion that routes addresses for the address space
 * @name: an address space name.  The name is only used for debugging
 *        output.
 */
void address_space_init(AddressSpace *as, MemoryRegion *root, const char *name);

/**
 * address_space_destroy: destroy an address space
 *
 * Releases all resources associated with an address space.  After an address space
 * is destroyed, its root memory region (given by address_space_init()) may be destroyed
 * as well.
 *
 * @as: address space to be destroyed
 */
void address_space_destroy(AddressSpace *as);

/**
 * address_space_rw: read from or write to an address space.
 *
 * Return a MemTxResult indicating whether the operation succeeded
 * or failed (eg unassigned memory, device rejected the transaction,
 * IOMMU fault).
 *
 * @as: #AddressSpace to be accessed
 * @addr: address within that address space
 * @attrs: memory transaction attributes
 * @buf: buffer with the data transferred
 * @len: the number of bytes to read or write
 * @is_write: indicates the transfer direction
 */
MemTxResult address_space_rw(AddressSpace *as, hwaddr addr,
                             MemTxAttrs attrs, uint8_t *buf,
                             hwaddr len, bool is_write);

/**
 * address_space_write: write to address space.
 *
 * Return a MemTxResult indicating whether the operation succeeded
 * or failed (eg unassigned memory, device rejected the transaction,
 * IOMMU fault).
 *
 * @as: #AddressSpace to be accessed
 * @addr: address within that address space
 * @attrs: memory transaction attributes
 * @buf: buffer with the data transferred
 * @len: the number of bytes to write
 */
MemTxResult address_space_write(AddressSpace *as, hwaddr addr,
                                MemTxAttrs attrs,
                                const uint8_t *buf, hwaddr len);

/**
 * address_space_write_rom: write to address space, including ROM.
 *
 * This function writes to the specified address space, but will
 * write data to both ROM and RAM. This is used for non-guest
 * writes like writes from the gdb debug stub or initial loading
 * of ROM contents.
 *
 * Note that portions of the write which attempt to write data to
 * a device will be silently ignored -- only real RAM and ROM will
 * be written to.
 *
 * Return a MemTxResult indicating whether the operation succeeded
 * or failed (eg unassigned memory, device rejected the transaction,
 * IOMMU fault).
 *
 * @as: #AddressSpace to be accessed
 * @addr: address within that address space
 * @attrs: memory transaction attributes
 * @buf: buffer with the data transferred
 * @len: the number of bytes to write
 */
MemTxResult address_space_write_rom(AddressSpace *as, hwaddr addr,
                                    MemTxAttrs attrs,
                                    const uint8_t *buf, hwaddr len);

/* address_space_ld*: load from an address space
 * address_space_st*: store to an address space
 *
 * These functions perform a load or store of the byte, word,
 * longword or quad to the specified address within the AddressSpace.
 * The _le suffixed functions treat the data as little endian;
 * _be indicates big endian; no suffix indicates "same endianness
 * as guest CPU".
 *
 * The "guest CPU endianness" accessors are deprecated for use outside
 * target-* code; devices should be CPU-agnostic and use either the LE
 * or the BE accessors.
 *
 * @as #AddressSpace to be accessed
 * @addr: address within that address space
 * @val: data value, for stores
 * @attrs: memory transaction attributes
 * @result: location to write the success/failure of the transaction;
 *   if NULL, this information is discarded
 */

#define SUFFIX
#define ARG1         as
#define ARG1_DECL    AddressSpace *as
#include "exec/memory_ldst.inc.h"

#define SUFFIX
#define ARG1         as
#define ARG1_DECL    AddressSpace *as
#include "exec/memory_ldst_phys.inc.h"

struct MemoryRegionCache {
    void *ptr;
    hwaddr xlat;
    hwaddr len;
    FlatView *fv;
    MemoryRegionSection mrs;
    bool is_write;
};

#define MEMORY_REGION_CACHE_INVALID ((MemoryRegionCache) { .mrs.mr = NULL })


/* address_space_ld*_cached: load from a cached #MemoryRegion
 * address_space_st*_cached: store into a cached #MemoryRegion
 *
 * These functions perform a load or store of the byte, word,
 * longword or quad to the specified address.  The address is
 * a physical address in the AddressSpace, but it must lie within
 * a #MemoryRegion that was mapped with address_space_cache_init.
 *
 * The _le suffixed functions treat the data as little endian;
 * _be indicates big endian; no suffix indicates "same endianness
 * as guest CPU".
 *
 * The "guest CPU endianness" accessors are deprecated for use outside
 * target-* code; devices should be CPU-agnostic and use either the LE
 * or the BE accessors.
 *
 * @cache: previously initialized #MemoryRegionCache to be accessed
 * @addr: address within the address space
 * @val: data value, for stores
 * @attrs: memory transaction attributes
 * @result: location to write the success/failure of the transaction;
 *   if NULL, this information is discarded
 */

#define SUFFIX       _cached_slow
#define ARG1         cache
#define ARG1_DECL    MemoryRegionCache *cache
#include "exec/memory_ldst.inc.h"

/* Inline fast path for direct RAM access.  */
static inline uint8_t address_space_ldub_cached(MemoryRegionCache *cache,
    hwaddr addr, MemTxAttrs attrs, MemTxResult *result)
{
    assert(addr < cache->len);
    if (likely(cache->ptr)) {
        return ldub_p(cache->ptr + addr);
    } else {
        return address_space_ldub_cached_slow(cache, addr, attrs, result);
    }
}

static inline void address_space_stb_cached(MemoryRegionCache *cache,
    hwaddr addr, uint32_t val, MemTxAttrs attrs, MemTxResult *result)
{
    assert(addr < cache->len);
    if (likely(cache->ptr)) {
        stb_p(cache->ptr + addr, val);
    } else {
        address_space_stb_cached_slow(cache, addr, val, attrs, result);
    }
}

#define ENDIANNESS   _le
#include "exec/memory_ldst_cached.inc.h"

#define ENDIANNESS   _be
#include "exec/memory_ldst_cached.inc.h"

#define SUFFIX       _cached
#define ARG1         cache
#define ARG1_DECL    MemoryRegionCache *cache
#include "exec/memory_ldst_phys.inc.h"

/* address_space_cache_init: prepare for repeated access to a physical
 * memory region
 *
 * @cache: #MemoryRegionCache to be filled
 * @as: #AddressSpace to be accessed
 * @addr: address within that address space
 * @len: length of buffer
 * @is_write: indicates the transfer direction
 *
 * Will only work with RAM, and may map a subset of the requested range by
 * returning a value that is less than @len.  On failure, return a negative
 * errno value.
 *
 * Because it only works with RAM, this function can be used for
 * read-modify-write operations.  In this case, is_write should be %true.
 *
 * Note that addresses passed to the address_space_*_cached functions
 * are relative to @addr.
 */
int64_t address_space_cache_init(MemoryRegionCache *cache,
                                 AddressSpace *as,
                                 hwaddr addr,
                                 hwaddr len,
                                 bool is_write);

/**
 * address_space_cache_invalidate: complete a write to a #MemoryRegionCache
 *
 * @cache: The #MemoryRegionCache to operate on.
 * @addr: The first physical address that was written, relative to the
 * address that was passed to @address_space_cache_init.
 * @access_len: The number of bytes that were written starting at @addr.
 */
void address_space_cache_invalidate(MemoryRegionCache *cache,
                                    hwaddr addr,
                                    hwaddr access_len);

/**
 * address_space_cache_destroy: free a #MemoryRegionCache
 *
 * @cache: The #MemoryRegionCache whose memory should be released.
 */
void address_space_cache_destroy(MemoryRegionCache *cache);

/* address_space_get_iotlb_entry: translate an address into an IOTLB
 * entry. Should be called from an RCU critical section.
 */
IOMMUTLBEntry address_space_get_iotlb_entry(AddressSpace *as, hwaddr addr,
                                            bool is_write, MemTxAttrs attrs);

/* address_space_translate: translate an address range into an address space
 * into a MemoryRegion and an address range into that section.  Should be
 * called from an RCU critical section, to avoid that the last reference
 * to the returned region disappears after address_space_translate returns.
 *
 * @fv: #FlatView to be accessed
 * @addr: address within that address space
 * @xlat: pointer to address within the returned memory region section's
 * #MemoryRegion.
 * @len: pointer to length
 * @is_write: indicates the transfer direction
 * @attrs: memory attributes
 */
MemoryRegion *flatview_translate(FlatView *fv,
                                 hwaddr addr, hwaddr *xlat,
                                 hwaddr *len, bool is_write,
                                 MemTxAttrs attrs);

static inline MemoryRegion *address_space_translate(AddressSpace *as,
                                                    hwaddr addr, hwaddr *xlat,
                                                    hwaddr *len, bool is_write,
                                                    MemTxAttrs attrs)
{
    return flatview_translate(address_space_to_flatview(as),
                              addr, xlat, len, is_write, attrs);
}

/* address_space_access_valid: check for validity of accessing an address
 * space range
 *
 * Check whether memory is assigned to the given address space range, and
 * access is permitted by any IOMMU regions that are active for the address
 * space.
 *
 * For now, addr and len should be aligned to a page size.  This limitation
 * will be lifted in the future.
 *
 * @as: #AddressSpace to be accessed
 * @addr: address within that address space
 * @len: length of the area to be checked
 * @is_write: indicates the transfer direction
 * @attrs: memory attributes
 */
bool address_space_access_valid(AddressSpace *as, hwaddr addr, hwaddr len,
                                bool is_write, MemTxAttrs attrs);

/* address_space_map: map a physical memory region into a host virtual address
 *
 * May map a subset of the requested range, given by and returned in @plen.
 * May return %NULL if resources needed to perform the mapping are exhausted.
 * Use only for reads OR writes - not for read-modify-write operations.
 * Use cpu_register_map_client() to know when retrying the map operation is
 * likely to succeed.
 *
 * @as: #AddressSpace to be accessed
 * @addr: address within that address space
 * @plen: pointer to length of buffer; updated on return
 * @is_write: indicates the transfer direction
 * @attrs: memory attributes
 */
void *address_space_map(AddressSpace *as, hwaddr addr,
                        hwaddr *plen, bool is_write, MemTxAttrs attrs);

/* address_space_unmap: Unmaps a memory region previously mapped by address_space_map()
 *
 * Will also mark the memory as dirty if @is_write == %true.  @access_len gives
 * the amount of memory that was actually read or written by the caller.
 *
 * @as: #AddressSpace used
 * @buffer: host pointer as returned by address_space_map()
 * @len: buffer length as returned by address_space_map()
 * @access_len: amount of data actually transferred
 * @is_write: indicates the transfer direction
 */
void address_space_unmap(AddressSpace *as, void *buffer, hwaddr len,
                         int is_write, hwaddr access_len);


/* Internal functions, part of the implementation of address_space_read.  */
MemTxResult address_space_read_full(AddressSpace *as, hwaddr addr,
                                    MemTxAttrs attrs, uint8_t *buf, hwaddr len);
MemTxResult flatview_read_continue(FlatView *fv, hwaddr addr,
                                   MemTxAttrs attrs, uint8_t *buf,
                                   hwaddr len, hwaddr addr1, hwaddr l,
                                   MemoryRegion *mr);
void *qemu_map_ram_ptr(RAMBlock *ram_block, ram_addr_t addr);

/* Internal functions, part of the implementation of address_space_read_cached
 * and address_space_write_cached.  */
void address_space_read_cached_slow(MemoryRegionCache *cache,
                                    hwaddr addr, void *buf, hwaddr len);
void address_space_write_cached_slow(MemoryRegionCache *cache,
                                     hwaddr addr, const void *buf, hwaddr len);

static inline bool memory_access_is_direct(MemoryRegion *mr, bool is_write)
{
    if (is_write) {
        return memory_region_is_ram(mr) &&
               !mr->readonly && !memory_region_is_ram_device(mr);
    } else {
        return (memory_region_is_ram(mr) && !memory_region_is_ram_device(mr)) ||
               memory_region_is_romd(mr);
    }
}

/**
 * address_space_read: read from an address space.
 *
 * Return a MemTxResult indicating whether the operation succeeded
 * or failed (eg unassigned memory, device rejected the transaction,
 * IOMMU fault).  Called within RCU critical section.
 *
 * @as: #AddressSpace to be accessed
 * @addr: address within that address space
 * @attrs: memory transaction attributes
 * @buf: buffer with the data transferred
 * @len: length of the buffer
 */
static inline __attribute__((__always_inline__))
MemTxResult address_space_read(AddressSpace *as, hwaddr addr,
                               MemTxAttrs attrs, uint8_t *buf,
                               hwaddr len)
{
    MemTxResult result = MEMTX_OK;
    hwaddr l, addr1;
    void *ptr;
    MemoryRegion *mr;
    FlatView *fv;

    if (__builtin_constant_p(len)) {
        if (len) {
            rcu_read_lock();
            fv = address_space_to_flatview(as);
            l = len;
            mr = flatview_translate(fv, addr, &addr1, &l, false, attrs);
            if (len == l && memory_access_is_direct(mr, false)) {
                ptr = qemu_map_ram_ptr(mr->ram_block, addr1);
                memcpy(buf, ptr, len);
            } else {
                result = flatview_read_continue(fv, addr, attrs, buf, len,
                                                addr1, l, mr);
            }
            rcu_read_unlock();
        }
    } else {
        result = address_space_read_full(as, addr, attrs, buf, len);
    }
    return result;
}

/**
 * address_space_read_cached: read from a cached RAM region
 *
 * @cache: Cached region to be addressed
 * @addr: address relative to the base of the RAM region
 * @buf: buffer with the data transferred
 * @len: length of the data transferred
 */
static inline void
address_space_read_cached(MemoryRegionCache *cache, hwaddr addr,
                          void *buf, hwaddr len)
{
    assert(addr < cache->len && len <= cache->len - addr);
    if (likely(cache->ptr)) {
        memcpy(buf, cache->ptr + addr, len);
    } else {
        address_space_read_cached_slow(cache, addr, buf, len);
    }
}

/**
 * address_space_write_cached: write to a cached RAM region
 *
 * @cache: Cached region to be addressed
 * @addr: address relative to the base of the RAM region
 * @buf: buffer with the data transferred
 * @len: length of the data transferred
 */
static inline void
address_space_write_cached(MemoryRegionCache *cache, hwaddr addr,
                           void *buf, hwaddr len)
{
    assert(addr < cache->len && len <= cache->len - addr);
    if (likely(cache->ptr)) {
        memcpy(cache->ptr + addr, buf, len);
    } else {
        address_space_write_cached_slow(cache, addr, buf, len);
    }
}

#endif

#endif