aboutsummaryrefslogtreecommitdiff
path: root/accel/kvm/kvm-all.c
blob: cace5ffe6442d7fe4112b5fdd3c2a2cece957181 (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
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621
3622
3623
3624
3625
3626
3627
3628
3629
3630
3631
3632
3633
3634
3635
3636
3637
3638
3639
3640
3641
3642
3643
3644
3645
3646
3647
3648
3649
3650
3651
3652
3653
3654
3655
3656
3657
3658
3659
/*
 * QEMU KVM support
 *
 * Copyright IBM, Corp. 2008
 *           Red Hat, Inc. 2008
 *
 * Authors:
 *  Anthony Liguori   <aliguori@us.ibm.com>
 *  Glauber Costa     <gcosta@redhat.com>
 *
 * This work is licensed under the terms of the GNU GPL, version 2 or later.
 * See the COPYING file in the top-level directory.
 *
 */

#include "qemu/osdep.h"
#include <sys/ioctl.h>
#include <poll.h>

#include <linux/kvm.h>

#include "qemu/atomic.h"
#include "qemu/option.h"
#include "qemu/config-file.h"
#include "qemu/error-report.h"
#include "qapi/error.h"
#include "hw/pci/msi.h"
#include "hw/pci/msix.h"
#include "hw/s390x/adapter.h"
#include "exec/gdbstub.h"
#include "sysemu/kvm_int.h"
#include "sysemu/runstate.h"
#include "sysemu/cpus.h"
#include "qemu/bswap.h"
#include "exec/memory.h"
#include "exec/ram_addr.h"
#include "qemu/event_notifier.h"
#include "qemu/main-loop.h"
#include "trace.h"
#include "hw/irq.h"
#include "qapi/visitor.h"
#include "qapi/qapi-types-common.h"
#include "qapi/qapi-visit-common.h"
#include "sysemu/reset.h"
#include "qemu/guest-random.h"
#include "sysemu/hw_accel.h"
#include "kvm-cpus.h"

#include "hw/boards.h"

/* This check must be after config-host.h is included */
#ifdef CONFIG_EVENTFD
#include <sys/eventfd.h>
#endif

/* KVM uses PAGE_SIZE in its definition of KVM_COALESCED_MMIO_MAX. We
 * need to use the real host PAGE_SIZE, as that's what KVM will use.
 */
#ifdef PAGE_SIZE
#undef PAGE_SIZE
#endif
#define PAGE_SIZE qemu_real_host_page_size

//#define DEBUG_KVM

#ifdef DEBUG_KVM
#define DPRINTF(fmt, ...) \
    do { fprintf(stderr, fmt, ## __VA_ARGS__); } while (0)
#else
#define DPRINTF(fmt, ...) \
    do { } while (0)
#endif

#define KVM_MSI_HASHTAB_SIZE    256

struct KVMParkedVcpu {
    unsigned long vcpu_id;
    int kvm_fd;
    QLIST_ENTRY(KVMParkedVcpu) node;
};

enum KVMDirtyRingReaperState {
    KVM_DIRTY_RING_REAPER_NONE = 0,
    /* The reaper is sleeping */
    KVM_DIRTY_RING_REAPER_WAIT,
    /* The reaper is reaping for dirty pages */
    KVM_DIRTY_RING_REAPER_REAPING,
};

/*
 * KVM reaper instance, responsible for collecting the KVM dirty bits
 * via the dirty ring.
 */
struct KVMDirtyRingReaper {
    /* The reaper thread */
    QemuThread reaper_thr;
    volatile uint64_t reaper_iteration; /* iteration number of reaper thr */
    volatile enum KVMDirtyRingReaperState reaper_state; /* reap thr state */
};

struct KVMState
{
    AccelState parent_obj;

    int nr_slots;
    int fd;
    int vmfd;
    int coalesced_mmio;
    int coalesced_pio;
    struct kvm_coalesced_mmio_ring *coalesced_mmio_ring;
    bool coalesced_flush_in_progress;
    int vcpu_events;
    int robust_singlestep;
    int debugregs;
#ifdef KVM_CAP_SET_GUEST_DEBUG
    QTAILQ_HEAD(, kvm_sw_breakpoint) kvm_sw_breakpoints;
#endif
    int max_nested_state_len;
    int many_ioeventfds;
    int intx_set_mask;
    int kvm_shadow_mem;
    bool kernel_irqchip_allowed;
    bool kernel_irqchip_required;
    OnOffAuto kernel_irqchip_split;
    bool sync_mmu;
    uint64_t manual_dirty_log_protect;
    /* The man page (and posix) say ioctl numbers are signed int, but
     * they're not.  Linux, glibc and *BSD all treat ioctl numbers as
     * unsigned, and treating them as signed here can break things */
    unsigned irq_set_ioctl;
    unsigned int sigmask_len;
    GHashTable *gsimap;
#ifdef KVM_CAP_IRQ_ROUTING
    struct kvm_irq_routing *irq_routes;
    int nr_allocated_irq_routes;
    unsigned long *used_gsi_bitmap;
    unsigned int gsi_count;
    QTAILQ_HEAD(, KVMMSIRoute) msi_hashtab[KVM_MSI_HASHTAB_SIZE];
#endif
    KVMMemoryListener memory_listener;
    QLIST_HEAD(, KVMParkedVcpu) kvm_parked_vcpus;

    /* For "info mtree -f" to tell if an MR is registered in KVM */
    int nr_as;
    struct KVMAs {
        KVMMemoryListener *ml;
        AddressSpace *as;
    } *as;
    uint64_t kvm_dirty_ring_bytes;  /* Size of the per-vcpu dirty ring */
    uint32_t kvm_dirty_ring_size;   /* Number of dirty GFNs per ring */
    struct KVMDirtyRingReaper reaper;
};

KVMState *kvm_state;
bool kvm_kernel_irqchip;
bool kvm_split_irqchip;
bool kvm_async_interrupts_allowed;
bool kvm_halt_in_kernel_allowed;
bool kvm_eventfds_allowed;
bool kvm_irqfds_allowed;
bool kvm_resamplefds_allowed;
bool kvm_msi_via_irqfd_allowed;
bool kvm_gsi_routing_allowed;
bool kvm_gsi_direct_mapping;
bool kvm_allowed;
bool kvm_readonly_mem_allowed;
bool kvm_vm_attributes_allowed;
bool kvm_direct_msi_allowed;
bool kvm_ioeventfd_any_length_allowed;
bool kvm_msi_use_devid;
static bool kvm_immediate_exit;
static hwaddr kvm_max_slot_size = ~0;

static const KVMCapabilityInfo kvm_required_capabilites[] = {
    KVM_CAP_INFO(USER_MEMORY),
    KVM_CAP_INFO(DESTROY_MEMORY_REGION_WORKS),
    KVM_CAP_INFO(JOIN_MEMORY_REGIONS_WORKS),
    KVM_CAP_LAST_INFO
};

static NotifierList kvm_irqchip_change_notifiers =
    NOTIFIER_LIST_INITIALIZER(kvm_irqchip_change_notifiers);

struct KVMResampleFd {
    int gsi;
    EventNotifier *resample_event;
    QLIST_ENTRY(KVMResampleFd) node;
};
typedef struct KVMResampleFd KVMResampleFd;

/*
 * Only used with split irqchip where we need to do the resample fd
 * kick for the kernel from userspace.
 */
static QLIST_HEAD(, KVMResampleFd) kvm_resample_fd_list =
    QLIST_HEAD_INITIALIZER(kvm_resample_fd_list);

static QemuMutex kml_slots_lock;

#define kvm_slots_lock()    qemu_mutex_lock(&kml_slots_lock)
#define kvm_slots_unlock()  qemu_mutex_unlock(&kml_slots_lock)

static void kvm_slot_init_dirty_bitmap(KVMSlot *mem);

static inline void kvm_resample_fd_remove(int gsi)
{
    KVMResampleFd *rfd;

    QLIST_FOREACH(rfd, &kvm_resample_fd_list, node) {
        if (rfd->gsi == gsi) {
            QLIST_REMOVE(rfd, node);
            g_free(rfd);
            break;
        }
    }
}

static inline void kvm_resample_fd_insert(int gsi, EventNotifier *event)
{
    KVMResampleFd *rfd = g_new0(KVMResampleFd, 1);

    rfd->gsi = gsi;
    rfd->resample_event = event;

    QLIST_INSERT_HEAD(&kvm_resample_fd_list, rfd, node);
}

void kvm_resample_fd_notify(int gsi)
{
    KVMResampleFd *rfd;

    QLIST_FOREACH(rfd, &kvm_resample_fd_list, node) {
        if (rfd->gsi == gsi) {
            event_notifier_set(rfd->resample_event);
            trace_kvm_resample_fd_notify(gsi);
            return;
        }
    }
}

int kvm_get_max_memslots(void)
{
    KVMState *s = KVM_STATE(current_accel());

    return s->nr_slots;
}

/* Called with KVMMemoryListener.slots_lock held */
static KVMSlot *kvm_get_free_slot(KVMMemoryListener *kml)
{
    KVMState *s = kvm_state;
    int i;

    for (i = 0; i < s->nr_slots; i++) {
        if (kml->slots[i].memory_size == 0) {
            return &kml->slots[i];
        }
    }

    return NULL;
}

bool kvm_has_free_slot(MachineState *ms)
{
    KVMState *s = KVM_STATE(ms->accelerator);
    bool result;
    KVMMemoryListener *kml = &s->memory_listener;

    kvm_slots_lock();
    result = !!kvm_get_free_slot(kml);
    kvm_slots_unlock();

    return result;
}

/* Called with KVMMemoryListener.slots_lock held */
static KVMSlot *kvm_alloc_slot(KVMMemoryListener *kml)
{
    KVMSlot *slot = kvm_get_free_slot(kml);

    if (slot) {
        return slot;
    }

    fprintf(stderr, "%s: no free slot available\n", __func__);
    abort();
}

static KVMSlot *kvm_lookup_matching_slot(KVMMemoryListener *kml,
                                         hwaddr start_addr,
                                         hwaddr size)
{
    KVMState *s = kvm_state;
    int i;

    for (i = 0; i < s->nr_slots; i++) {
        KVMSlot *mem = &kml->slots[i];

        if (start_addr == mem->start_addr && size == mem->memory_size) {
            return mem;
        }
    }

    return NULL;
}

/*
 * Calculate and align the start address and the size of the section.
 * Return the size. If the size is 0, the aligned section is empty.
 */
static hwaddr kvm_align_section(MemoryRegionSection *section,
                                hwaddr *start)
{
    hwaddr size = int128_get64(section->size);
    hwaddr delta, aligned;

    /* kvm works in page size chunks, but the function may be called
       with sub-page size and unaligned start address. Pad the start
       address to next and truncate size to previous page boundary. */
    aligned = ROUND_UP(section->offset_within_address_space,
                       qemu_real_host_page_size);
    delta = aligned - section->offset_within_address_space;
    *start = aligned;
    if (delta > size) {
        return 0;
    }

    return (size - delta) & qemu_real_host_page_mask;
}

int kvm_physical_memory_addr_from_host(KVMState *s, void *ram,
                                       hwaddr *phys_addr)
{
    KVMMemoryListener *kml = &s->memory_listener;
    int i, ret = 0;

    kvm_slots_lock();
    for (i = 0; i < s->nr_slots; i++) {
        KVMSlot *mem = &kml->slots[i];

        if (ram >= mem->ram && ram < mem->ram + mem->memory_size) {
            *phys_addr = mem->start_addr + (ram - mem->ram);
            ret = 1;
            break;
        }
    }
    kvm_slots_unlock();

    return ret;
}

static int kvm_set_user_memory_region(KVMMemoryListener *kml, KVMSlot *slot, bool new)
{
    KVMState *s = kvm_state;
    struct kvm_userspace_memory_region mem;
    int ret;

    mem.slot = slot->slot | (kml->as_id << 16);
    mem.guest_phys_addr = slot->start_addr;
    mem.userspace_addr = (unsigned long)slot->ram;
    mem.flags = slot->flags;

    if (slot->memory_size && !new && (mem.flags ^ slot->old_flags) & KVM_MEM_READONLY) {
        /* Set the slot size to 0 before setting the slot to the desired
         * value. This is needed based on KVM commit 75d61fbc. */
        mem.memory_size = 0;
        ret = kvm_vm_ioctl(s, KVM_SET_USER_MEMORY_REGION, &mem);
        if (ret < 0) {
            goto err;
        }
    }
    mem.memory_size = slot->memory_size;
    ret = kvm_vm_ioctl(s, KVM_SET_USER_MEMORY_REGION, &mem);
    slot->old_flags = mem.flags;
err:
    trace_kvm_set_user_memory(mem.slot, mem.flags, mem.guest_phys_addr,
                              mem.memory_size, mem.userspace_addr, ret);
    if (ret < 0) {
        error_report("%s: KVM_SET_USER_MEMORY_REGION failed, slot=%d,"
                     " start=0x%" PRIx64 ", size=0x%" PRIx64 ": %s",
                     __func__, mem.slot, slot->start_addr,
                     (uint64_t)mem.memory_size, strerror(errno));
    }
    return ret;
}

static int do_kvm_destroy_vcpu(CPUState *cpu)
{
    KVMState *s = kvm_state;
    long mmap_size;
    struct KVMParkedVcpu *vcpu = NULL;
    int ret = 0;

    DPRINTF("kvm_destroy_vcpu\n");

    ret = kvm_arch_destroy_vcpu(cpu);
    if (ret < 0) {
        goto err;
    }

    mmap_size = kvm_ioctl(s, KVM_GET_VCPU_MMAP_SIZE, 0);
    if (mmap_size < 0) {
        ret = mmap_size;
        DPRINTF("KVM_GET_VCPU_MMAP_SIZE failed\n");
        goto err;
    }

    ret = munmap(cpu->kvm_run, mmap_size);
    if (ret < 0) {
        goto err;
    }

    if (cpu->kvm_dirty_gfns) {
        ret = munmap(cpu->kvm_dirty_gfns, s->kvm_dirty_ring_bytes);
        if (ret < 0) {
            goto err;
        }
    }

    vcpu = g_malloc0(sizeof(*vcpu));
    vcpu->vcpu_id = kvm_arch_vcpu_id(cpu);
    vcpu->kvm_fd = cpu->kvm_fd;
    QLIST_INSERT_HEAD(&kvm_state->kvm_parked_vcpus, vcpu, node);
err:
    return ret;
}

void kvm_destroy_vcpu(CPUState *cpu)
{
    if (do_kvm_destroy_vcpu(cpu) < 0) {
        error_report("kvm_destroy_vcpu failed");
        exit(EXIT_FAILURE);
    }
}

static int kvm_get_vcpu(KVMState *s, unsigned long vcpu_id)
{
    struct KVMParkedVcpu *cpu;

    QLIST_FOREACH(cpu, &s->kvm_parked_vcpus, node) {
        if (cpu->vcpu_id == vcpu_id) {
            int kvm_fd;

            QLIST_REMOVE(cpu, node);
            kvm_fd = cpu->kvm_fd;
            g_free(cpu);
            return kvm_fd;
        }
    }

    return kvm_vm_ioctl(s, KVM_CREATE_VCPU, (void *)vcpu_id);
}

int kvm_init_vcpu(CPUState *cpu, Error **errp)
{
    KVMState *s = kvm_state;
    long mmap_size;
    int ret;

    trace_kvm_init_vcpu(cpu->cpu_index, kvm_arch_vcpu_id(cpu));

    ret = kvm_get_vcpu(s, kvm_arch_vcpu_id(cpu));
    if (ret < 0) {
        error_setg_errno(errp, -ret, "kvm_init_vcpu: kvm_get_vcpu failed (%lu)",
                         kvm_arch_vcpu_id(cpu));
        goto err;
    }

    cpu->kvm_fd = ret;
    cpu->kvm_state = s;
    cpu->vcpu_dirty = true;

    mmap_size = kvm_ioctl(s, KVM_GET_VCPU_MMAP_SIZE, 0);
    if (mmap_size < 0) {
        ret = mmap_size;
        error_setg_errno(errp, -mmap_size,
                         "kvm_init_vcpu: KVM_GET_VCPU_MMAP_SIZE failed");
        goto err;
    }

    cpu->kvm_run = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED,
                        cpu->kvm_fd, 0);
    if (cpu->kvm_run == MAP_FAILED) {
        ret = -errno;
        error_setg_errno(errp, ret,
                         "kvm_init_vcpu: mmap'ing vcpu state failed (%lu)",
                         kvm_arch_vcpu_id(cpu));
        goto err;
    }

    if (s->coalesced_mmio && !s->coalesced_mmio_ring) {
        s->coalesced_mmio_ring =
            (void *)cpu->kvm_run + s->coalesced_mmio * PAGE_SIZE;
    }

    if (s->kvm_dirty_ring_size) {
        /* Use MAP_SHARED to share pages with the kernel */
        cpu->kvm_dirty_gfns = mmap(NULL, s->kvm_dirty_ring_bytes,
                                   PROT_READ | PROT_WRITE, MAP_SHARED,
                                   cpu->kvm_fd,
                                   PAGE_SIZE * KVM_DIRTY_LOG_PAGE_OFFSET);
        if (cpu->kvm_dirty_gfns == MAP_FAILED) {
            ret = -errno;
            DPRINTF("mmap'ing vcpu dirty gfns failed: %d\n", ret);
            goto err;
        }
    }

    ret = kvm_arch_init_vcpu(cpu);
    if (ret < 0) {
        error_setg_errno(errp, -ret,
                         "kvm_init_vcpu: kvm_arch_init_vcpu failed (%lu)",
                         kvm_arch_vcpu_id(cpu));
    }
err:
    return ret;
}

/*
 * dirty pages logging control
 */

static int kvm_mem_flags(MemoryRegion *mr)
{
    bool readonly = mr->readonly || memory_region_is_romd(mr);
    int flags = 0;

    if (memory_region_get_dirty_log_mask(mr) != 0) {
        flags |= KVM_MEM_LOG_DIRTY_PAGES;
    }
    if (readonly && kvm_readonly_mem_allowed) {
        flags |= KVM_MEM_READONLY;
    }
    return flags;
}

/* Called with KVMMemoryListener.slots_lock held */
static int kvm_slot_update_flags(KVMMemoryListener *kml, KVMSlot *mem,
                                 MemoryRegion *mr)
{
    mem->flags = kvm_mem_flags(mr);

    /* If nothing changed effectively, no need to issue ioctl */
    if (mem->flags == mem->old_flags) {
        return 0;
    }

    kvm_slot_init_dirty_bitmap(mem);
    return kvm_set_user_memory_region(kml, mem, false);
}

static int kvm_section_update_flags(KVMMemoryListener *kml,
                                    MemoryRegionSection *section)
{
    hwaddr start_addr, size, slot_size;
    KVMSlot *mem;
    int ret = 0;

    size = kvm_align_section(section, &start_addr);
    if (!size) {
        return 0;
    }

    kvm_slots_lock();

    while (size && !ret) {
        slot_size = MIN(kvm_max_slot_size, size);
        mem = kvm_lookup_matching_slot(kml, start_addr, slot_size);
        if (!mem) {
            /* We don't have a slot if we want to trap every access. */
            goto out;
        }

        ret = kvm_slot_update_flags(kml, mem, section->mr);
        start_addr += slot_size;
        size -= slot_size;
    }

out:
    kvm_slots_unlock();
    return ret;
}

static void kvm_log_start(MemoryListener *listener,
                          MemoryRegionSection *section,
                          int old, int new)
{
    KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, listener);
    int r;

    if (old != 0) {
        return;
    }

    r = kvm_section_update_flags(kml, section);
    if (r < 0) {
        abort();
    }
}

static void kvm_log_stop(MemoryListener *listener,
                          MemoryRegionSection *section,
                          int old, int new)
{
    KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, listener);
    int r;

    if (new != 0) {
        return;
    }

    r = kvm_section_update_flags(kml, section);
    if (r < 0) {
        abort();
    }
}

/* get kvm's dirty pages bitmap and update qemu's */
static void kvm_slot_sync_dirty_pages(KVMSlot *slot)
{
    ram_addr_t start = slot->ram_start_offset;
    ram_addr_t pages = slot->memory_size / qemu_real_host_page_size;

    cpu_physical_memory_set_dirty_lebitmap(slot->dirty_bmap, start, pages);
}

static void kvm_slot_reset_dirty_pages(KVMSlot *slot)
{
    memset(slot->dirty_bmap, 0, slot->dirty_bmap_size);
}

#define ALIGN(x, y)  (((x)+(y)-1) & ~((y)-1))

/* Allocate the dirty bitmap for a slot  */
static void kvm_slot_init_dirty_bitmap(KVMSlot *mem)
{
    if (!(mem->flags & KVM_MEM_LOG_DIRTY_PAGES) || mem->dirty_bmap) {
        return;
    }

    /*
     * XXX bad kernel interface alert
     * For dirty bitmap, kernel allocates array of size aligned to
     * bits-per-long.  But for case when the kernel is 64bits and
     * the userspace is 32bits, userspace can't align to the same
     * bits-per-long, since sizeof(long) is different between kernel
     * and user space.  This way, userspace will provide buffer which
     * may be 4 bytes less than the kernel will use, resulting in
     * userspace memory corruption (which is not detectable by valgrind
     * too, in most cases).
     * So for now, let's align to 64 instead of HOST_LONG_BITS here, in
     * a hope that sizeof(long) won't become >8 any time soon.
     *
     * Note: the granule of kvm dirty log is qemu_real_host_page_size.
     * And mem->memory_size is aligned to it (otherwise this mem can't
     * be registered to KVM).
     */
    hwaddr bitmap_size = ALIGN(mem->memory_size / qemu_real_host_page_size,
                                        /*HOST_LONG_BITS*/ 64) / 8;
    mem->dirty_bmap = g_malloc0(bitmap_size);
    mem->dirty_bmap_size = bitmap_size;
}

/*
 * Sync dirty bitmap from kernel to KVMSlot.dirty_bmap, return true if
 * succeeded, false otherwise
 */
static bool kvm_slot_get_dirty_log(KVMState *s, KVMSlot *slot)
{
    struct kvm_dirty_log d = {};
    int ret;

    d.dirty_bitmap = slot->dirty_bmap;
    d.slot = slot->slot | (slot->as_id << 16);
    ret = kvm_vm_ioctl(s, KVM_GET_DIRTY_LOG, &d);

    if (ret == -ENOENT) {
        /* kernel does not have dirty bitmap in this slot */
        ret = 0;
    }
    if (ret) {
        error_report_once("%s: KVM_GET_DIRTY_LOG failed with %d",
                          __func__, ret);
    }
    return ret == 0;
}

/* Should be with all slots_lock held for the address spaces. */
static void kvm_dirty_ring_mark_page(KVMState *s, uint32_t as_id,
                                     uint32_t slot_id, uint64_t offset)
{
    KVMMemoryListener *kml;
    KVMSlot *mem;

    if (as_id >= s->nr_as) {
        return;
    }

    kml = s->as[as_id].ml;
    mem = &kml->slots[slot_id];

    if (!mem->memory_size || offset >=
        (mem->memory_size / qemu_real_host_page_size)) {
        return;
    }

    set_bit(offset, mem->dirty_bmap);
}

static bool dirty_gfn_is_dirtied(struct kvm_dirty_gfn *gfn)
{
    return gfn->flags == KVM_DIRTY_GFN_F_DIRTY;
}

static void dirty_gfn_set_collected(struct kvm_dirty_gfn *gfn)
{
    gfn->flags = KVM_DIRTY_GFN_F_RESET;
}

/*
 * Should be with all slots_lock held for the address spaces.  It returns the
 * dirty page we've collected on this dirty ring.
 */
static uint32_t kvm_dirty_ring_reap_one(KVMState *s, CPUState *cpu)
{
    struct kvm_dirty_gfn *dirty_gfns = cpu->kvm_dirty_gfns, *cur;
    uint32_t ring_size = s->kvm_dirty_ring_size;
    uint32_t count = 0, fetch = cpu->kvm_fetch_index;

    assert(dirty_gfns && ring_size);
    trace_kvm_dirty_ring_reap_vcpu(cpu->cpu_index);

    while (true) {
        cur = &dirty_gfns[fetch % ring_size];
        if (!dirty_gfn_is_dirtied(cur)) {
            break;
        }
        kvm_dirty_ring_mark_page(s, cur->slot >> 16, cur->slot & 0xffff,
                                 cur->offset);
        dirty_gfn_set_collected(cur);
        trace_kvm_dirty_ring_page(cpu->cpu_index, fetch, cur->offset);
        fetch++;
        count++;
    }
    cpu->kvm_fetch_index = fetch;

    return count;
}

/* Must be with slots_lock held */
static uint64_t kvm_dirty_ring_reap_locked(KVMState *s)
{
    int ret;
    CPUState *cpu;
    uint64_t total = 0;
    int64_t stamp;

    stamp = get_clock();

    CPU_FOREACH(cpu) {
        total += kvm_dirty_ring_reap_one(s, cpu);
    }

    if (total) {
        ret = kvm_vm_ioctl(s, KVM_RESET_DIRTY_RINGS);
        assert(ret == total);
    }

    stamp = get_clock() - stamp;

    if (total) {
        trace_kvm_dirty_ring_reap(total, stamp / 1000);
    }

    return total;
}

/*
 * Currently for simplicity, we must hold BQL before calling this.  We can
 * consider to drop the BQL if we're clear with all the race conditions.
 */
static uint64_t kvm_dirty_ring_reap(KVMState *s)
{
    uint64_t total;

    /*
     * We need to lock all kvm slots for all address spaces here,
     * because:
     *
     * (1) We need to mark dirty for dirty bitmaps in multiple slots
     *     and for tons of pages, so it's better to take the lock here
     *     once rather than once per page.  And more importantly,
     *
     * (2) We must _NOT_ publish dirty bits to the other threads
     *     (e.g., the migration thread) via the kvm memory slot dirty
     *     bitmaps before correctly re-protect those dirtied pages.
     *     Otherwise we can have potential risk of data corruption if
     *     the page data is read in the other thread before we do
     *     reset below.
     */
    kvm_slots_lock();
    total = kvm_dirty_ring_reap_locked(s);
    kvm_slots_unlock();

    return total;
}

static void do_kvm_cpu_synchronize_kick(CPUState *cpu, run_on_cpu_data arg)
{
    /* No need to do anything */
}

/*
 * Kick all vcpus out in a synchronized way.  When returned, we
 * guarantee that every vcpu has been kicked and at least returned to
 * userspace once.
 */
static void kvm_cpu_synchronize_kick_all(void)
{
    CPUState *cpu;

    CPU_FOREACH(cpu) {
        run_on_cpu(cpu, do_kvm_cpu_synchronize_kick, RUN_ON_CPU_NULL);
    }
}

/*
 * Flush all the existing dirty pages to the KVM slot buffers.  When
 * this call returns, we guarantee that all the touched dirty pages
 * before calling this function have been put into the per-kvmslot
 * dirty bitmap.
 *
 * This function must be called with BQL held.
 */
static void kvm_dirty_ring_flush(void)
{
    trace_kvm_dirty_ring_flush(0);
    /*
     * The function needs to be serialized.  Since this function
     * should always be with BQL held, serialization is guaranteed.
     * However, let's be sure of it.
     */
    assert(qemu_mutex_iothread_locked());
    /*
     * First make sure to flush the hardware buffers by kicking all
     * vcpus out in a synchronous way.
     */
    kvm_cpu_synchronize_kick_all();
    kvm_dirty_ring_reap(kvm_state);
    trace_kvm_dirty_ring_flush(1);
}

/**
 * kvm_physical_sync_dirty_bitmap - Sync dirty bitmap from kernel space
 *
 * This function will first try to fetch dirty bitmap from the kernel,
 * and then updates qemu's dirty bitmap.
 *
 * NOTE: caller must be with kml->slots_lock held.
 *
 * @kml: the KVM memory listener object
 * @section: the memory section to sync the dirty bitmap with
 */
static void kvm_physical_sync_dirty_bitmap(KVMMemoryListener *kml,
                                           MemoryRegionSection *section)
{
    KVMState *s = kvm_state;
    KVMSlot *mem;
    hwaddr start_addr, size;
    hwaddr slot_size;

    size = kvm_align_section(section, &start_addr);
    while (size) {
        slot_size = MIN(kvm_max_slot_size, size);
        mem = kvm_lookup_matching_slot(kml, start_addr, slot_size);
        if (!mem) {
            /* We don't have a slot if we want to trap every access. */
            return;
        }
        if (kvm_slot_get_dirty_log(s, mem)) {
            kvm_slot_sync_dirty_pages(mem);
        }
        start_addr += slot_size;
        size -= slot_size;
    }
}

/* Alignment requirement for KVM_CLEAR_DIRTY_LOG - 64 pages */
#define KVM_CLEAR_LOG_SHIFT  6
#define KVM_CLEAR_LOG_ALIGN  (qemu_real_host_page_size << KVM_CLEAR_LOG_SHIFT)
#define KVM_CLEAR_LOG_MASK   (-KVM_CLEAR_LOG_ALIGN)

static int kvm_log_clear_one_slot(KVMSlot *mem, int as_id, uint64_t start,
                                  uint64_t size)
{
    KVMState *s = kvm_state;
    uint64_t end, bmap_start, start_delta, bmap_npages;
    struct kvm_clear_dirty_log d;
    unsigned long *bmap_clear = NULL, psize = qemu_real_host_page_size;
    int ret;

    /*
     * We need to extend either the start or the size or both to
     * satisfy the KVM interface requirement.  Firstly, do the start
     * page alignment on 64 host pages
     */
    bmap_start = start & KVM_CLEAR_LOG_MASK;
    start_delta = start - bmap_start;
    bmap_start /= psize;

    /*
     * The kernel interface has restriction on the size too, that either:
     *
     * (1) the size is 64 host pages aligned (just like the start), or
     * (2) the size fills up until the end of the KVM memslot.
     */
    bmap_npages = DIV_ROUND_UP(size + start_delta, KVM_CLEAR_LOG_ALIGN)
        << KVM_CLEAR_LOG_SHIFT;
    end = mem->memory_size / psize;
    if (bmap_npages > end - bmap_start) {
        bmap_npages = end - bmap_start;
    }
    start_delta /= psize;

    /*
     * Prepare the bitmap to clear dirty bits.  Here we must guarantee
     * that we won't clear any unknown dirty bits otherwise we might
     * accidentally clear some set bits which are not yet synced from
     * the kernel into QEMU's bitmap, then we'll lose track of the
     * guest modifications upon those pages (which can directly lead
     * to guest data loss or panic after migration).
     *
     * Layout of the KVMSlot.dirty_bmap:
     *
     *                   |<-------- bmap_npages -----------..>|
     *                                                     [1]
     *                     start_delta         size
     *  |----------------|-------------|------------------|------------|
     *  ^                ^             ^                               ^
     *  |                |             |                               |
     * start          bmap_start     (start)                         end
     * of memslot                                             of memslot
     *
     * [1] bmap_npages can be aligned to either 64 pages or the end of slot
     */

    assert(bmap_start % BITS_PER_LONG == 0);
    /* We should never do log_clear before log_sync */
    assert(mem->dirty_bmap);
    if (start_delta || bmap_npages - size / psize) {
        /* Slow path - we need to manipulate a temp bitmap */
        bmap_clear = bitmap_new(bmap_npages);
        bitmap_copy_with_src_offset(bmap_clear, mem->dirty_bmap,
                                    bmap_start, start_delta + size / psize);
        /*
         * We need to fill the holes at start because that was not
         * specified by the caller and we extended the bitmap only for
         * 64 pages alignment
         */
        bitmap_clear(bmap_clear, 0, start_delta);
        d.dirty_bitmap = bmap_clear;
    } else {
        /*
         * Fast path - both start and size align well with BITS_PER_LONG
         * (or the end of memory slot)
         */
        d.dirty_bitmap = mem->dirty_bmap + BIT_WORD(bmap_start);
    }

    d.first_page = bmap_start;
    /* It should never overflow.  If it happens, say something */
    assert(bmap_npages <= UINT32_MAX);
    d.num_pages = bmap_npages;
    d.slot = mem->slot | (as_id << 16);

    ret = kvm_vm_ioctl(s, KVM_CLEAR_DIRTY_LOG, &d);
    if (ret < 0 && ret != -ENOENT) {
        error_report("%s: KVM_CLEAR_DIRTY_LOG failed, slot=%d, "
                     "start=0x%"PRIx64", size=0x%"PRIx32", errno=%d",
                     __func__, d.slot, (uint64_t)d.first_page,
                     (uint32_t)d.num_pages, ret);
    } else {
        ret = 0;
        trace_kvm_clear_dirty_log(d.slot, d.first_page, d.num_pages);
    }

    /*
     * After we have updated the remote dirty bitmap, we update the
     * cached bitmap as well for the memslot, then if another user
     * clears the same region we know we shouldn't clear it again on
     * the remote otherwise it's data loss as well.
     */
    bitmap_clear(mem->dirty_bmap, bmap_start + start_delta,
                 size / psize);
    /* This handles the NULL case well */
    g_free(bmap_clear);
    return ret;
}


/**
 * kvm_physical_log_clear - Clear the kernel's dirty bitmap for range
 *
 * NOTE: this will be a no-op if we haven't enabled manual dirty log
 * protection in the host kernel because in that case this operation
 * will be done within log_sync().
 *
 * @kml:     the kvm memory listener
 * @section: the memory range to clear dirty bitmap
 */
static int kvm_physical_log_clear(KVMMemoryListener *kml,
                                  MemoryRegionSection *section)
{
    KVMState *s = kvm_state;
    uint64_t start, size, offset, count;
    KVMSlot *mem;
    int ret = 0, i;

    if (!s->manual_dirty_log_protect) {
        /* No need to do explicit clear */
        return ret;
    }

    start = section->offset_within_address_space;
    size = int128_get64(section->size);

    if (!size) {
        /* Nothing more we can do... */
        return ret;
    }

    kvm_slots_lock();

    for (i = 0; i < s->nr_slots; i++) {
        mem = &kml->slots[i];
        /* Discard slots that are empty or do not overlap the section */
        if (!mem->memory_size ||
            mem->start_addr > start + size - 1 ||
            start > mem->start_addr + mem->memory_size - 1) {
            continue;
        }

        if (start >= mem->start_addr) {
            /* The slot starts before section or is aligned to it.  */
            offset = start - mem->start_addr;
            count = MIN(mem->memory_size - offset, size);
        } else {
            /* The slot starts after section.  */
            offset = 0;
            count = MIN(mem->memory_size, size - (mem->start_addr - start));
        }
        ret = kvm_log_clear_one_slot(mem, kml->as_id, offset, count);
        if (ret < 0) {
            break;
        }
    }

    kvm_slots_unlock();

    return ret;
}

static void kvm_coalesce_mmio_region(MemoryListener *listener,
                                     MemoryRegionSection *secion,
                                     hwaddr start, hwaddr size)
{
    KVMState *s = kvm_state;

    if (s->coalesced_mmio) {
        struct kvm_coalesced_mmio_zone zone;

        zone.addr = start;
        zone.size = size;
        zone.pad = 0;

        (void)kvm_vm_ioctl(s, KVM_REGISTER_COALESCED_MMIO, &zone);
    }
}

static void kvm_uncoalesce_mmio_region(MemoryListener *listener,
                                       MemoryRegionSection *secion,
                                       hwaddr start, hwaddr size)
{
    KVMState *s = kvm_state;

    if (s->coalesced_mmio) {
        struct kvm_coalesced_mmio_zone zone;

        zone.addr = start;
        zone.size = size;
        zone.pad = 0;

        (void)kvm_vm_ioctl(s, KVM_UNREGISTER_COALESCED_MMIO, &zone);
    }
}

static void kvm_coalesce_pio_add(MemoryListener *listener,
                                MemoryRegionSection *section,
                                hwaddr start, hwaddr size)
{
    KVMState *s = kvm_state;

    if (s->coalesced_pio) {
        struct kvm_coalesced_mmio_zone zone;

        zone.addr = start;
        zone.size = size;
        zone.pio = 1;

        (void)kvm_vm_ioctl(s, KVM_REGISTER_COALESCED_MMIO, &zone);
    }
}

static void kvm_coalesce_pio_del(MemoryListener *listener,
                                MemoryRegionSection *section,
                                hwaddr start, hwaddr size)
{
    KVMState *s = kvm_state;

    if (s->coalesced_pio) {
        struct kvm_coalesced_mmio_zone zone;

        zone.addr = start;
        zone.size = size;
        zone.pio = 1;

        (void)kvm_vm_ioctl(s, KVM_UNREGISTER_COALESCED_MMIO, &zone);
     }
}

static MemoryListener kvm_coalesced_pio_listener = {
    .coalesced_io_add = kvm_coalesce_pio_add,
    .coalesced_io_del = kvm_coalesce_pio_del,
};

int kvm_check_extension(KVMState *s, unsigned int extension)
{
    int ret;

    ret = kvm_ioctl(s, KVM_CHECK_EXTENSION, extension);
    if (ret < 0) {
        ret = 0;
    }

    return ret;
}

int kvm_vm_check_extension(KVMState *s, unsigned int extension)
{
    int ret;

    ret = kvm_vm_ioctl(s, KVM_CHECK_EXTENSION, extension);
    if (ret < 0) {
        /* VM wide version not implemented, use global one instead */
        ret = kvm_check_extension(s, extension);
    }

    return ret;
}

typedef struct HWPoisonPage {
    ram_addr_t ram_addr;
    QLIST_ENTRY(HWPoisonPage) list;
} HWPoisonPage;

static QLIST_HEAD(, HWPoisonPage) hwpoison_page_list =
    QLIST_HEAD_INITIALIZER(hwpoison_page_list);

static void kvm_unpoison_all(void *param)
{
    HWPoisonPage *page, *next_page;

    QLIST_FOREACH_SAFE(page, &hwpoison_page_list, list, next_page) {
        QLIST_REMOVE(page, list);
        qemu_ram_remap(page->ram_addr, TARGET_PAGE_SIZE);
        g_free(page);
    }
}

void kvm_hwpoison_page_add(ram_addr_t ram_addr)
{
    HWPoisonPage *page;

    QLIST_FOREACH(page, &hwpoison_page_list, list) {
        if (page->ram_addr == ram_addr) {
            return;
        }
    }
    page = g_new(HWPoisonPage, 1);
    page->ram_addr = ram_addr;
    QLIST_INSERT_HEAD(&hwpoison_page_list, page, list);
}

static uint32_t adjust_ioeventfd_endianness(uint32_t val, uint32_t size)
{
#if defined(HOST_WORDS_BIGENDIAN) != defined(TARGET_WORDS_BIGENDIAN)
    /* The kernel expects ioeventfd values in HOST_WORDS_BIGENDIAN
     * endianness, but the memory core hands them in target endianness.
     * For example, PPC is always treated as big-endian even if running
     * on KVM and on PPC64LE.  Correct here.
     */
    switch (size) {
    case 2:
        val = bswap16(val);
        break;
    case 4:
        val = bswap32(val);
        break;
    }
#endif
    return val;
}

static int kvm_set_ioeventfd_mmio(int fd, hwaddr addr, uint32_t val,
                                  bool assign, uint32_t size, bool datamatch)
{
    int ret;
    struct kvm_ioeventfd iofd = {
        .datamatch = datamatch ? adjust_ioeventfd_endianness(val, size) : 0,
        .addr = addr,
        .len = size,
        .flags = 0,
        .fd = fd,
    };

    trace_kvm_set_ioeventfd_mmio(fd, (uint64_t)addr, val, assign, size,
                                 datamatch);
    if (!kvm_enabled()) {
        return -ENOSYS;
    }

    if (datamatch) {
        iofd.flags |= KVM_IOEVENTFD_FLAG_DATAMATCH;
    }
    if (!assign) {
        iofd.flags |= KVM_IOEVENTFD_FLAG_DEASSIGN;
    }

    ret = kvm_vm_ioctl(kvm_state, KVM_IOEVENTFD, &iofd);

    if (ret < 0) {
        return -errno;
    }

    return 0;
}

static int kvm_set_ioeventfd_pio(int fd, uint16_t addr, uint16_t val,
                                 bool assign, uint32_t size, bool datamatch)
{
    struct kvm_ioeventfd kick = {
        .datamatch = datamatch ? adjust_ioeventfd_endianness(val, size) : 0,
        .addr = addr,
        .flags = KVM_IOEVENTFD_FLAG_PIO,
        .len = size,
        .fd = fd,
    };
    int r;
    trace_kvm_set_ioeventfd_pio(fd, addr, val, assign, size, datamatch);
    if (!kvm_enabled()) {
        return -ENOSYS;
    }
    if (datamatch) {
        kick.flags |= KVM_IOEVENTFD_FLAG_DATAMATCH;
    }
    if (!assign) {
        kick.flags |= KVM_IOEVENTFD_FLAG_DEASSIGN;
    }
    r = kvm_vm_ioctl(kvm_state, KVM_IOEVENTFD, &kick);
    if (r < 0) {
        return r;
    }
    return 0;
}


static int kvm_check_many_ioeventfds(void)
{
    /* Userspace can use ioeventfd for io notification.  This requires a host
     * that supports eventfd(2) and an I/O thread; since eventfd does not
     * support SIGIO it cannot interrupt the vcpu.
     *
     * Older kernels have a 6 device limit on the KVM io bus.  Find out so we
     * can avoid creating too many ioeventfds.
     */
#if defined(CONFIG_EVENTFD)
    int ioeventfds[7];
    int i, ret = 0;
    for (i = 0; i < ARRAY_SIZE(ioeventfds); i++) {
        ioeventfds[i] = eventfd(0, EFD_CLOEXEC);
        if (ioeventfds[i] < 0) {
            break;
        }
        ret = kvm_set_ioeventfd_pio(ioeventfds[i], 0, i, true, 2, true);
        if (ret < 0) {
            close(ioeventfds[i]);
            break;
        }
    }

    /* Decide whether many devices are supported or not */
    ret = i == ARRAY_SIZE(ioeventfds);

    while (i-- > 0) {
        kvm_set_ioeventfd_pio(ioeventfds[i], 0, i, false, 2, true);
        close(ioeventfds[i]);
    }
    return ret;
#else
    return 0;
#endif
}

static const KVMCapabilityInfo *
kvm_check_extension_list(KVMState *s, const KVMCapabilityInfo *list)
{
    while (list->name) {
        if (!kvm_check_extension(s, list->value)) {
            return list;
        }
        list++;
    }
    return NULL;
}

void kvm_set_max_memslot_size(hwaddr max_slot_size)
{
    g_assert(
        ROUND_UP(max_slot_size, qemu_real_host_page_size) == max_slot_size
    );
    kvm_max_slot_size = max_slot_size;
}

static void kvm_set_phys_mem(KVMMemoryListener *kml,
                             MemoryRegionSection *section, bool add)
{
    KVMSlot *mem;
    int err;
    MemoryRegion *mr = section->mr;
    bool writeable = !mr->readonly && !mr->rom_device;
    hwaddr start_addr, size, slot_size, mr_offset;
    ram_addr_t ram_start_offset;
    void *ram;

    if (!memory_region_is_ram(mr)) {
        if (writeable || !kvm_readonly_mem_allowed) {
            return;
        } else if (!mr->romd_mode) {
            /* If the memory device is not in romd_mode, then we actually want
             * to remove the kvm memory slot so all accesses will trap. */
            add = false;
        }
    }

    size = kvm_align_section(section, &start_addr);
    if (!size) {
        return;
    }

    /* The offset of the kvmslot within the memory region */
    mr_offset = section->offset_within_region + start_addr -
        section->offset_within_address_space;

    /* use aligned delta to align the ram address and offset */
    ram = memory_region_get_ram_ptr(mr) + mr_offset;
    ram_start_offset = memory_region_get_ram_addr(mr) + mr_offset;

    kvm_slots_lock();

    if (!add) {
        do {
            slot_size = MIN(kvm_max_slot_size, size);
            mem = kvm_lookup_matching_slot(kml, start_addr, slot_size);
            if (!mem) {
                goto out;
            }
            if (mem->flags & KVM_MEM_LOG_DIRTY_PAGES) {
                /*
                 * NOTE: We should be aware of the fact that here we're only
                 * doing a best effort to sync dirty bits.  No matter whether
                 * we're using dirty log or dirty ring, we ignored two facts:
                 *
                 * (1) dirty bits can reside in hardware buffers (PML)
                 *
                 * (2) after we collected dirty bits here, pages can be dirtied
                 * again before we do the final KVM_SET_USER_MEMORY_REGION to
                 * remove the slot.
                 *
                 * Not easy.  Let's cross the fingers until it's fixed.
                 */
                if (kvm_state->kvm_dirty_ring_size) {
                    kvm_dirty_ring_reap_locked(kvm_state);
                } else {
                    kvm_slot_get_dirty_log(kvm_state, mem);
                }
                kvm_slot_sync_dirty_pages(mem);
            }

            /* unregister the slot */
            g_free(mem->dirty_bmap);
            mem->dirty_bmap = NULL;
            mem->memory_size = 0;
            mem->flags = 0;
            err = kvm_set_user_memory_region(kml, mem, false);
            if (err) {
                fprintf(stderr, "%s: error unregistering slot: %s\n",
                        __func__, strerror(-err));
                abort();
            }
            start_addr += slot_size;
            size -= slot_size;
        } while (size);
        goto out;
    }

    /* register the new slot */
    do {
        slot_size = MIN(kvm_max_slot_size, size);
        mem = kvm_alloc_slot(kml);
        mem->as_id = kml->as_id;
        mem->memory_size = slot_size;
        mem->start_addr = start_addr;
        mem->ram_start_offset = ram_start_offset;
        mem->ram = ram;
        mem->flags = kvm_mem_flags(mr);
        kvm_slot_init_dirty_bitmap(mem);
        err = kvm_set_user_memory_region(kml, mem, true);
        if (err) {
            fprintf(stderr, "%s: error registering slot: %s\n", __func__,
                    strerror(-err));
            abort();
        }
        start_addr += slot_size;
        ram_start_offset += slot_size;
        ram += slot_size;
        size -= slot_size;
    } while (size);

out:
    kvm_slots_unlock();
}

static void *kvm_dirty_ring_reaper_thread(void *data)
{
    KVMState *s = data;
    struct KVMDirtyRingReaper *r = &s->reaper;

    rcu_register_thread();

    trace_kvm_dirty_ring_reaper("init");

    while (true) {
        r->reaper_state = KVM_DIRTY_RING_REAPER_WAIT;
        trace_kvm_dirty_ring_reaper("wait");
        /*
         * TODO: provide a smarter timeout rather than a constant?
         */
        sleep(1);

        trace_kvm_dirty_ring_reaper("wakeup");
        r->reaper_state = KVM_DIRTY_RING_REAPER_REAPING;

        qemu_mutex_lock_iothread();
        kvm_dirty_ring_reap(s);
        qemu_mutex_unlock_iothread();

        r->reaper_iteration++;
    }

    trace_kvm_dirty_ring_reaper("exit");

    rcu_unregister_thread();

    return NULL;
}

static int kvm_dirty_ring_reaper_init(KVMState *s)
{
    struct KVMDirtyRingReaper *r = &s->reaper;

    qemu_thread_create(&r->reaper_thr, "kvm-reaper",
                       kvm_dirty_ring_reaper_thread,
                       s, QEMU_THREAD_JOINABLE);

    return 0;
}

static void kvm_region_add(MemoryListener *listener,
                           MemoryRegionSection *section)
{
    KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, listener);

    memory_region_ref(section->mr);
    kvm_set_phys_mem(kml, section, true);
}

static void kvm_region_del(MemoryListener *listener,
                           MemoryRegionSection *section)
{
    KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, listener);

    kvm_set_phys_mem(kml, section, false);
    memory_region_unref(section->mr);
}

static void kvm_log_sync(MemoryListener *listener,
                         MemoryRegionSection *section)
{
    KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, listener);

    kvm_slots_lock();
    kvm_physical_sync_dirty_bitmap(kml, section);
    kvm_slots_unlock();
}

static void kvm_log_sync_global(MemoryListener *l)
{
    KVMMemoryListener *kml = container_of(l, KVMMemoryListener, listener);
    KVMState *s = kvm_state;
    KVMSlot *mem;
    int i;

    /* Flush all kernel dirty addresses into KVMSlot dirty bitmap */
    kvm_dirty_ring_flush();

    /*
     * TODO: make this faster when nr_slots is big while there are
     * only a few used slots (small VMs).
     */
    kvm_slots_lock();
    for (i = 0; i < s->nr_slots; i++) {
        mem = &kml->slots[i];
        if (mem->memory_size && mem->flags & KVM_MEM_LOG_DIRTY_PAGES) {
            kvm_slot_sync_dirty_pages(mem);
            /*
             * This is not needed by KVM_GET_DIRTY_LOG because the
             * ioctl will unconditionally overwrite the whole region.
             * However kvm dirty ring has no such side effect.
             */
            kvm_slot_reset_dirty_pages(mem);
        }
    }
    kvm_slots_unlock();
}

static void kvm_log_clear(MemoryListener *listener,
                          MemoryRegionSection *section)
{
    KVMMemoryListener *kml = container_of(listener, KVMMemoryListener, listener);
    int r;

    r = kvm_physical_log_clear(kml, section);
    if (r < 0) {
        error_report_once("%s: kvm log clear failed: mr=%s "
                          "offset=%"HWADDR_PRIx" size=%"PRIx64, __func__,
                          section->mr->name, section->offset_within_region,
                          int128_get64(section->size));
        abort();
    }
}

static void kvm_mem_ioeventfd_add(MemoryListener *listener,
                                  MemoryRegionSection *section,
                                  bool match_data, uint64_t data,
                                  EventNotifier *e)
{
    int fd = event_notifier_get_fd(e);
    int r;

    r = kvm_set_ioeventfd_mmio(fd, section->offset_within_address_space,
                               data, true, int128_get64(section->size),
                               match_data);
    if (r < 0) {
        fprintf(stderr, "%s: error adding ioeventfd: %s (%d)\n",
                __func__, strerror(-r), -r);
        abort();
    }
}

static void kvm_mem_ioeventfd_del(MemoryListener *listener,
                                  MemoryRegionSection *section,
                                  bool match_data, uint64_t data,
                                  EventNotifier *e)
{
    int fd = event_notifier_get_fd(e);
    int r;

    r = kvm_set_ioeventfd_mmio(fd, section->offset_within_address_space,
                               data, false, int128_get64(section->size),
                               match_data);
    if (r < 0) {
        fprintf(stderr, "%s: error deleting ioeventfd: %s (%d)\n",
                __func__, strerror(-r), -r);
        abort();
    }
}

static void kvm_io_ioeventfd_add(MemoryListener *listener,
                                 MemoryRegionSection *section,
                                 bool match_data, uint64_t data,
                                 EventNotifier *e)
{
    int fd = event_notifier_get_fd(e);
    int r;

    r = kvm_set_ioeventfd_pio(fd, section->offset_within_address_space,
                              data, true, int128_get64(section->size),
                              match_data);
    if (r < 0) {
        fprintf(stderr, "%s: error adding ioeventfd: %s (%d)\n",
                __func__, strerror(-r), -r);
        abort();
    }
}

static void kvm_io_ioeventfd_del(MemoryListener *listener,
                                 MemoryRegionSection *section,
                                 bool match_data, uint64_t data,
                                 EventNotifier *e)

{
    int fd = event_notifier_get_fd(e);
    int r;

    r = kvm_set_ioeventfd_pio(fd, section->offset_within_address_space,
                              data, false, int128_get64(section->size),
                              match_data);
    if (r < 0) {
        fprintf(stderr, "%s: error deleting ioeventfd: %s (%d)\n",
                __func__, strerror(-r), -r);
        abort();
    }
}

void kvm_memory_listener_register(KVMState *s, KVMMemoryListener *kml,
                                  AddressSpace *as, int as_id)
{
    int i;

    kml->slots = g_malloc0(s->nr_slots * sizeof(KVMSlot));
    kml->as_id = as_id;

    for (i = 0; i < s->nr_slots; i++) {
        kml->slots[i].slot = i;
    }

    kml->listener.region_add = kvm_region_add;
    kml->listener.region_del = kvm_region_del;
    kml->listener.log_start = kvm_log_start;
    kml->listener.log_stop = kvm_log_stop;
    kml->listener.priority = 10;

    if (s->kvm_dirty_ring_size) {
        kml->listener.log_sync_global = kvm_log_sync_global;
    } else {
        kml->listener.log_sync = kvm_log_sync;
        kml->listener.log_clear = kvm_log_clear;
    }

    memory_listener_register(&kml->listener, as);

    for (i = 0; i < s->nr_as; ++i) {
        if (!s->as[i].as) {
            s->as[i].as = as;
            s->as[i].ml = kml;
            break;
        }
    }
}

static MemoryListener kvm_io_listener = {
    .eventfd_add = kvm_io_ioeventfd_add,
    .eventfd_del = kvm_io_ioeventfd_del,
    .priority = 10,
};

int kvm_set_irq(KVMState *s, int irq, int level)
{
    struct kvm_irq_level event;
    int ret;

    assert(kvm_async_interrupts_enabled());

    event.level = level;
    event.irq = irq;
    ret = kvm_vm_ioctl(s, s->irq_set_ioctl, &event);
    if (ret < 0) {
        perror("kvm_set_irq");
        abort();
    }

    return (s->irq_set_ioctl == KVM_IRQ_LINE) ? 1 : event.status;
}

#ifdef KVM_CAP_IRQ_ROUTING
typedef struct KVMMSIRoute {
    struct kvm_irq_routing_entry kroute;
    QTAILQ_ENTRY(KVMMSIRoute) entry;
} KVMMSIRoute;

static void set_gsi(KVMState *s, unsigned int gsi)
{
    set_bit(gsi, s->used_gsi_bitmap);
}

static void clear_gsi(KVMState *s, unsigned int gsi)
{
    clear_bit(gsi, s->used_gsi_bitmap);
}

void kvm_init_irq_routing(KVMState *s)
{
    int gsi_count, i;

    gsi_count = kvm_check_extension(s, KVM_CAP_IRQ_ROUTING) - 1;
    if (gsi_count > 0) {
        /* Round up so we can search ints using ffs */
        s->used_gsi_bitmap = bitmap_new(gsi_count);
        s->gsi_count = gsi_count;
    }

    s->irq_routes = g_malloc0(sizeof(*s->irq_routes));
    s->nr_allocated_irq_routes = 0;

    if (!kvm_direct_msi_allowed) {
        for (i = 0; i < KVM_MSI_HASHTAB_SIZE; i++) {
            QTAILQ_INIT(&s->msi_hashtab[i]);
        }
    }

    kvm_arch_init_irq_routing(s);
}

void kvm_irqchip_commit_routes(KVMState *s)
{
    int ret;

    if (kvm_gsi_direct_mapping()) {
        return;
    }

    if (!kvm_gsi_routing_enabled()) {
        return;
    }

    s->irq_routes->flags = 0;
    trace_kvm_irqchip_commit_routes();
    ret = kvm_vm_ioctl(s, KVM_SET_GSI_ROUTING, s->irq_routes);
    assert(ret == 0);
}

static void kvm_add_routing_entry(KVMState *s,
                                  struct kvm_irq_routing_entry *entry)
{
    struct kvm_irq_routing_entry *new;
    int n, size;

    if (s->irq_routes->nr == s->nr_allocated_irq_routes) {
        n = s->nr_allocated_irq_routes * 2;
        if (n < 64) {
            n = 64;
        }
        size = sizeof(struct kvm_irq_routing);
        size += n * sizeof(*new);
        s->irq_routes = g_realloc(s->irq_routes, size);
        s->nr_allocated_irq_routes = n;
    }
    n = s->irq_routes->nr++;
    new = &s->irq_routes->entries[n];

    *new = *entry;

    set_gsi(s, entry->gsi);
}

static int kvm_update_routing_entry(KVMState *s,
                                    struct kvm_irq_routing_entry *new_entry)
{
    struct kvm_irq_routing_entry *entry;
    int n;

    for (n = 0; n < s->irq_routes->nr; n++) {
        entry = &s->irq_routes->entries[n];
        if (entry->gsi != new_entry->gsi) {
            continue;
        }

        if(!memcmp(entry, new_entry, sizeof *entry)) {
            return 0;
        }

        *entry = *new_entry;

        return 0;
    }

    return -ESRCH;
}

void kvm_irqchip_add_irq_route(KVMState *s, int irq, int irqchip, int pin)
{
    struct kvm_irq_routing_entry e = {};

    assert(pin < s->gsi_count);

    e.gsi = irq;
    e.type = KVM_IRQ_ROUTING_IRQCHIP;
    e.flags = 0;
    e.u.irqchip.irqchip = irqchip;
    e.u.irqchip.pin = pin;
    kvm_add_routing_entry(s, &e);
}

void kvm_irqchip_release_virq(KVMState *s, int virq)
{
    struct kvm_irq_routing_entry *e;
    int i;

    if (kvm_gsi_direct_mapping()) {
        return;
    }

    for (i = 0; i < s->irq_routes->nr; i++) {
        e = &s->irq_routes->entries[i];
        if (e->gsi == virq) {
            s->irq_routes->nr--;
            *e = s->irq_routes->entries[s->irq_routes->nr];
        }
    }
    clear_gsi(s, virq);
    kvm_arch_release_virq_post(virq);
    trace_kvm_irqchip_release_virq(virq);
}

void kvm_irqchip_add_change_notifier(Notifier *n)
{
    notifier_list_add(&kvm_irqchip_change_notifiers, n);
}

void kvm_irqchip_remove_change_notifier(Notifier *n)
{
    notifier_remove(n);
}

void kvm_irqchip_change_notify(void)
{
    notifier_list_notify(&kvm_irqchip_change_notifiers, NULL);
}

static unsigned int kvm_hash_msi(uint32_t data)
{
    /* This is optimized for IA32 MSI layout. However, no other arch shall
     * repeat the mistake of not providing a direct MSI injection API. */
    return data & 0xff;
}

static void kvm_flush_dynamic_msi_routes(KVMState *s)
{
    KVMMSIRoute *route, *next;
    unsigned int hash;

    for (hash = 0; hash < KVM_MSI_HASHTAB_SIZE; hash++) {
        QTAILQ_FOREACH_SAFE(route, &s->msi_hashtab[hash], entry, next) {
            kvm_irqchip_release_virq(s, route->kroute.gsi);
            QTAILQ_REMOVE(&s->msi_hashtab[hash], route, entry);
            g_free(route);
        }
    }
}

static int kvm_irqchip_get_virq(KVMState *s)
{
    int next_virq;

    /*
     * PIC and IOAPIC share the first 16 GSI numbers, thus the available
     * GSI numbers are more than the number of IRQ route. Allocating a GSI
     * number can succeed even though a new route entry cannot be added.
     * When this happens, flush dynamic MSI entries to free IRQ route entries.
     */
    if (!kvm_direct_msi_allowed && s->irq_routes->nr == s->gsi_count) {
        kvm_flush_dynamic_msi_routes(s);
    }

    /* Return the lowest unused GSI in the bitmap */
    next_virq = find_first_zero_bit(s->used_gsi_bitmap, s->gsi_count);
    if (next_virq >= s->gsi_count) {
        return -ENOSPC;
    } else {
        return next_virq;
    }
}

static KVMMSIRoute *kvm_lookup_msi_route(KVMState *s, MSIMessage msg)
{
    unsigned int hash = kvm_hash_msi(msg.data);
    KVMMSIRoute *route;

    QTAILQ_FOREACH(route, &s->msi_hashtab[hash], entry) {
        if (route->kroute.u.msi.address_lo == (uint32_t)msg.address &&
            route->kroute.u.msi.address_hi == (msg.address >> 32) &&
            route->kroute.u.msi.data == le32_to_cpu(msg.data)) {
            return route;
        }
    }
    return NULL;
}

int kvm_irqchip_send_msi(KVMState *s, MSIMessage msg)
{
    struct kvm_msi msi;
    KVMMSIRoute *route;

    if (kvm_direct_msi_allowed) {
        msi.address_lo = (uint32_t)msg.address;
        msi.address_hi = msg.address >> 32;
        msi.data = le32_to_cpu(msg.data);
        msi.flags = 0;
        memset(msi.pad, 0, sizeof(msi.pad));

        return kvm_vm_ioctl(s, KVM_SIGNAL_MSI, &msi);
    }

    route = kvm_lookup_msi_route(s, msg);
    if (!route) {
        int virq;

        virq = kvm_irqchip_get_virq(s);
        if (virq < 0) {
            return virq;
        }

        route = g_malloc0(sizeof(KVMMSIRoute));
        route->kroute.gsi = virq;
        route->kroute.type = KVM_IRQ_ROUTING_MSI;
        route->kroute.flags = 0;
        route->kroute.u.msi.address_lo = (uint32_t)msg.address;
        route->kroute.u.msi.address_hi = msg.address >> 32;
        route->kroute.u.msi.data = le32_to_cpu(msg.data);

        kvm_add_routing_entry(s, &route->kroute);
        kvm_irqchip_commit_routes(s);

        QTAILQ_INSERT_TAIL(&s->msi_hashtab[kvm_hash_msi(msg.data)], route,
                           entry);
    }

    assert(route->kroute.type == KVM_IRQ_ROUTING_MSI);

    return kvm_set_irq(s, route->kroute.gsi, 1);
}

int kvm_irqchip_add_msi_route(KVMState *s, int vector, PCIDevice *dev)
{
    struct kvm_irq_routing_entry kroute = {};
    int virq;
    MSIMessage msg = {0, 0};

    if (pci_available && dev) {
        msg = pci_get_msi_message(dev, vector);
    }

    if (kvm_gsi_direct_mapping()) {
        return kvm_arch_msi_data_to_gsi(msg.data);
    }

    if (!kvm_gsi_routing_enabled()) {
        return -ENOSYS;
    }

    virq = kvm_irqchip_get_virq(s);
    if (virq < 0) {
        return virq;
    }

    kroute.gsi = virq;
    kroute.type = KVM_IRQ_ROUTING_MSI;
    kroute.flags = 0;
    kroute.u.msi.address_lo = (uint32_t)msg.address;
    kroute.u.msi.address_hi = msg.address >> 32;
    kroute.u.msi.data = le32_to_cpu(msg.data);
    if (pci_available && kvm_msi_devid_required()) {
        kroute.flags = KVM_MSI_VALID_DEVID;
        kroute.u.msi.devid = pci_requester_id(dev);
    }
    if (kvm_arch_fixup_msi_route(&kroute, msg.address, msg.data, dev)) {
        kvm_irqchip_release_virq(s, virq);
        return -EINVAL;
    }

    trace_kvm_irqchip_add_msi_route(dev ? dev->name : (char *)"N/A",
                                    vector, virq);

    kvm_add_routing_entry(s, &kroute);
    kvm_arch_add_msi_route_post(&kroute, vector, dev);
    kvm_irqchip_commit_routes(s);

    return virq;
}

int kvm_irqchip_update_msi_route(KVMState *s, int virq, MSIMessage msg,
                                 PCIDevice *dev)
{
    struct kvm_irq_routing_entry kroute = {};

    if (kvm_gsi_direct_mapping()) {
        return 0;
    }

    if (!kvm_irqchip_in_kernel()) {
        return -ENOSYS;
    }

    kroute.gsi = virq;
    kroute.type = KVM_IRQ_ROUTING_MSI;
    kroute.flags = 0;
    kroute.u.msi.address_lo = (uint32_t)msg.address;
    kroute.u.msi.address_hi = msg.address >> 32;
    kroute.u.msi.data = le32_to_cpu(msg.data);
    if (pci_available && kvm_msi_devid_required()) {
        kroute.flags = KVM_MSI_VALID_DEVID;
        kroute.u.msi.devid = pci_requester_id(dev);
    }
    if (kvm_arch_fixup_msi_route(&kroute, msg.address, msg.data, dev)) {
        return -EINVAL;
    }

    trace_kvm_irqchip_update_msi_route(virq);

    return kvm_update_routing_entry(s, &kroute);
}

static int kvm_irqchip_assign_irqfd(KVMState *s, EventNotifier *event,
                                    EventNotifier *resample, int virq,
                                    bool assign)
{
    int fd = event_notifier_get_fd(event);
    int rfd = resample ? event_notifier_get_fd(resample) : -1;

    struct kvm_irqfd irqfd = {
        .fd = fd,
        .gsi = virq,
        .flags = assign ? 0 : KVM_IRQFD_FLAG_DEASSIGN,
    };

    if (rfd != -1) {
        assert(assign);
        if (kvm_irqchip_is_split()) {
            /*
             * When the slow irqchip (e.g. IOAPIC) is in the
             * userspace, KVM kernel resamplefd will not work because
             * the EOI of the interrupt will be delivered to userspace
             * instead, so the KVM kernel resamplefd kick will be
             * skipped.  The userspace here mimics what the kernel
             * provides with resamplefd, remember the resamplefd and
             * kick it when we receive EOI of this IRQ.
             *
             * This is hackery because IOAPIC is mostly bypassed
             * (except EOI broadcasts) when irqfd is used.  However
             * this can bring much performance back for split irqchip
             * with INTx IRQs (for VFIO, this gives 93% perf of the
             * full fast path, which is 46% perf boost comparing to
             * the INTx slow path).
             */
            kvm_resample_fd_insert(virq, resample);
        } else {
            irqfd.flags |= KVM_IRQFD_FLAG_RESAMPLE;
            irqfd.resamplefd = rfd;
        }
    } else if (!assign) {
        if (kvm_irqchip_is_split()) {
            kvm_resample_fd_remove(virq);
        }
    }

    if (!kvm_irqfds_enabled()) {
        return -ENOSYS;
    }

    return kvm_vm_ioctl(s, KVM_IRQFD, &irqfd);
}

int kvm_irqchip_add_adapter_route(KVMState *s, AdapterInfo *adapter)
{
    struct kvm_irq_routing_entry kroute = {};
    int virq;

    if (!kvm_gsi_routing_enabled()) {
        return -ENOSYS;
    }

    virq = kvm_irqchip_get_virq(s);
    if (virq < 0) {
        return virq;
    }

    kroute.gsi = virq;
    kroute.type = KVM_IRQ_ROUTING_S390_ADAPTER;
    kroute.flags = 0;
    kroute.u.adapter.summary_addr = adapter->summary_addr;
    kroute.u.adapter.ind_addr = adapter->ind_addr;
    kroute.u.adapter.summary_offset = adapter->summary_offset;
    kroute.u.adapter.ind_offset = adapter->ind_offset;
    kroute.u.adapter.adapter_id = adapter->adapter_id;

    kvm_add_routing_entry(s, &kroute);

    return virq;
}

int kvm_irqchip_add_hv_sint_route(KVMState *s, uint32_t vcpu, uint32_t sint)
{
    struct kvm_irq_routing_entry kroute = {};
    int virq;

    if (!kvm_gsi_routing_enabled()) {
        return -ENOSYS;
    }
    if (!kvm_check_extension(s, KVM_CAP_HYPERV_SYNIC)) {
        return -ENOSYS;
    }
    virq = kvm_irqchip_get_virq(s);
    if (virq < 0) {
        return virq;
    }

    kroute.gsi = virq;
    kroute.type = KVM_IRQ_ROUTING_HV_SINT;
    kroute.flags = 0;
    kroute.u.hv_sint.vcpu = vcpu;
    kroute.u.hv_sint.sint = sint;

    kvm_add_routing_entry(s, &kroute);
    kvm_irqchip_commit_routes(s);

    return virq;
}

#else /* !KVM_CAP_IRQ_ROUTING */

void kvm_init_irq_routing(KVMState *s)
{
}

void kvm_irqchip_release_virq(KVMState *s, int virq)
{
}

int kvm_irqchip_send_msi(KVMState *s, MSIMessage msg)
{
    abort();
}

int kvm_irqchip_add_msi_route(KVMState *s, int vector, PCIDevice *dev)
{
    return -ENOSYS;
}

int kvm_irqchip_add_adapter_route(KVMState *s, AdapterInfo *adapter)
{
    return -ENOSYS;
}

int kvm_irqchip_add_hv_sint_route(KVMState *s, uint32_t vcpu, uint32_t sint)
{
    return -ENOSYS;
}

static int kvm_irqchip_assign_irqfd(KVMState *s, EventNotifier *event,
                                    EventNotifier *resample, int virq,
                                    bool assign)
{
    abort();
}

int kvm_irqchip_update_msi_route(KVMState *s, int virq, MSIMessage msg)
{
    return -ENOSYS;
}
#endif /* !KVM_CAP_IRQ_ROUTING */

int kvm_irqchip_add_irqfd_notifier_gsi(KVMState *s, EventNotifier *n,
                                       EventNotifier *rn, int virq)
{
    return kvm_irqchip_assign_irqfd(s, n, rn, virq, true);
}

int kvm_irqchip_remove_irqfd_notifier_gsi(KVMState *s, EventNotifier *n,
                                          int virq)
{
    return kvm_irqchip_assign_irqfd(s, n, NULL, virq, false);
}

int kvm_irqchip_add_irqfd_notifier(KVMState *s, EventNotifier *n,
                                   EventNotifier *rn, qemu_irq irq)
{
    gpointer key, gsi;
    gboolean found = g_hash_table_lookup_extended(s->gsimap, irq, &key, &gsi);

    if (!found) {
        return -ENXIO;
    }
    return kvm_irqchip_add_irqfd_notifier_gsi(s, n, rn, GPOINTER_TO_INT(gsi));
}

int kvm_irqchip_remove_irqfd_notifier(KVMState *s, EventNotifier *n,
                                      qemu_irq irq)
{
    gpointer key, gsi;
    gboolean found = g_hash_table_lookup_extended(s->gsimap, irq, &key, &gsi);

    if (!found) {
        return -ENXIO;
    }
    return kvm_irqchip_remove_irqfd_notifier_gsi(s, n, GPOINTER_TO_INT(gsi));
}

void kvm_irqchip_set_qemuirq_gsi(KVMState *s, qemu_irq irq, int gsi)
{
    g_hash_table_insert(s->gsimap, irq, GINT_TO_POINTER(gsi));
}

static void kvm_irqchip_create(KVMState *s)
{
    int ret;

    assert(s->kernel_irqchip_split != ON_OFF_AUTO_AUTO);
    if (kvm_check_extension(s, KVM_CAP_IRQCHIP)) {
        ;
    } else if (kvm_check_extension(s, KVM_CAP_S390_IRQCHIP)) {
        ret = kvm_vm_enable_cap(s, KVM_CAP_S390_IRQCHIP, 0);
        if (ret < 0) {
            fprintf(stderr, "Enable kernel irqchip failed: %s\n", strerror(-ret));
            exit(1);
        }
    } else {
        return;
    }

    /* First probe and see if there's a arch-specific hook to create the
     * in-kernel irqchip for us */
    ret = kvm_arch_irqchip_create(s);
    if (ret == 0) {
        if (s->kernel_irqchip_split == ON_OFF_AUTO_ON) {
            perror("Split IRQ chip mode not supported.");
            exit(1);
        } else {
            ret = kvm_vm_ioctl(s, KVM_CREATE_IRQCHIP);
        }
    }
    if (ret < 0) {
        fprintf(stderr, "Create kernel irqchip failed: %s\n", strerror(-ret));
        exit(1);
    }

    kvm_kernel_irqchip = true;
    /* If we have an in-kernel IRQ chip then we must have asynchronous
     * interrupt delivery (though the reverse is not necessarily true)
     */
    kvm_async_interrupts_allowed = true;
    kvm_halt_in_kernel_allowed = true;

    kvm_init_irq_routing(s);

    s->gsimap = g_hash_table_new(g_direct_hash, g_direct_equal);
}

/* Find number of supported CPUs using the recommended
 * procedure from the kernel API documentation to cope with
 * older kernels that may be missing capabilities.
 */
static int kvm_recommended_vcpus(KVMState *s)
{
    int ret = kvm_vm_check_extension(s, KVM_CAP_NR_VCPUS);
    return (ret) ? ret : 4;
}

static int kvm_max_vcpus(KVMState *s)
{
    int ret = kvm_check_extension(s, KVM_CAP_MAX_VCPUS);
    return (ret) ? ret : kvm_recommended_vcpus(s);
}

static int kvm_max_vcpu_id(KVMState *s)
{
    int ret = kvm_check_extension(s, KVM_CAP_MAX_VCPU_ID);
    return (ret) ? ret : kvm_max_vcpus(s);
}

bool kvm_vcpu_id_is_valid(int vcpu_id)
{
    KVMState *s = KVM_STATE(current_accel());
    return vcpu_id >= 0 && vcpu_id < kvm_max_vcpu_id(s);
}

static int kvm_init(MachineState *ms)
{
    MachineClass *mc = MACHINE_GET_CLASS(ms);
    static const char upgrade_note[] =
        "Please upgrade to at least kernel 2.6.29 or recent kvm-kmod\n"
        "(see http://sourceforge.net/projects/kvm).\n";
    struct {
        const char *name;
        int num;
    } num_cpus[] = {
        { "SMP",          ms->smp.cpus },
        { "hotpluggable", ms->smp.max_cpus },
        { NULL, }
    }, *nc = num_cpus;
    int soft_vcpus_limit, hard_vcpus_limit;
    KVMState *s;
    const KVMCapabilityInfo *missing_cap;
    int ret;
    int type = 0;
    uint64_t dirty_log_manual_caps;

    qemu_mutex_init(&kml_slots_lock);

    s = KVM_STATE(ms->accelerator);

    /*
     * On systems where the kernel can support different base page
     * sizes, host page size may be different from TARGET_PAGE_SIZE,
     * even with KVM.  TARGET_PAGE_SIZE is assumed to be the minimum
     * page size for the system though.
     */
    assert(TARGET_PAGE_SIZE <= qemu_real_host_page_size);

    s->sigmask_len = 8;

#ifdef KVM_CAP_SET_GUEST_DEBUG
    QTAILQ_INIT(&s->kvm_sw_breakpoints);
#endif
    QLIST_INIT(&s->kvm_parked_vcpus);
    s->fd = qemu_open_old("/dev/kvm", O_RDWR);
    if (s->fd == -1) {
        fprintf(stderr, "Could not access KVM kernel module: %m\n");
        ret = -errno;
        goto err;
    }

    ret = kvm_ioctl(s, KVM_GET_API_VERSION, 0);
    if (ret < KVM_API_VERSION) {
        if (ret >= 0) {
            ret = -EINVAL;
        }
        fprintf(stderr, "kvm version too old\n");
        goto err;
    }

    if (ret > KVM_API_VERSION) {
        ret = -EINVAL;
        fprintf(stderr, "kvm version not supported\n");
        goto err;
    }

    kvm_immediate_exit = kvm_check_extension(s, KVM_CAP_IMMEDIATE_EXIT);
    s->nr_slots = kvm_check_extension(s, KVM_CAP_NR_MEMSLOTS);

    /* If unspecified, use the default value */
    if (!s->nr_slots) {
        s->nr_slots = 32;
    }

    s->nr_as = kvm_check_extension(s, KVM_CAP_MULTI_ADDRESS_SPACE);
    if (s->nr_as <= 1) {
        s->nr_as = 1;
    }
    s->as = g_new0(struct KVMAs, s->nr_as);

    if (object_property_find(OBJECT(current_machine), "kvm-type")) {
        g_autofree char *kvm_type = object_property_get_str(OBJECT(current_machine),
                                                            "kvm-type",
                                                            &error_abort);
        type = mc->kvm_type(ms, kvm_type);
    } else if (mc->kvm_type) {
        type = mc->kvm_type(ms, NULL);
    }

    do {
        ret = kvm_ioctl(s, KVM_CREATE_VM, type);
    } while (ret == -EINTR);

    if (ret < 0) {
        fprintf(stderr, "ioctl(KVM_CREATE_VM) failed: %d %s\n", -ret,
                strerror(-ret));

#ifdef TARGET_S390X
        if (ret == -EINVAL) {
            fprintf(stderr,
                    "Host kernel setup problem detected. Please verify:\n");
            fprintf(stderr, "- for kernels supporting the switch_amode or"
                    " user_mode parameters, whether\n");
            fprintf(stderr,
                    "  user space is running in primary address space\n");
            fprintf(stderr,
                    "- for kernels supporting the vm.allocate_pgste sysctl, "
                    "whether it is enabled\n");
        }
#elif defined(TARGET_PPC)
        if (ret == -EINVAL) {
            fprintf(stderr,
                    "PPC KVM module is not loaded. Try modprobe kvm_%s.\n",
                    (type == 2) ? "pr" : "hv");
        }
#endif
        goto err;
    }

    s->vmfd = ret;

    /* check the vcpu limits */
    soft_vcpus_limit = kvm_recommended_vcpus(s);
    hard_vcpus_limit = kvm_max_vcpus(s);

    while (nc->name) {
        if (nc->num > soft_vcpus_limit) {
            warn_report("Number of %s cpus requested (%d) exceeds "
                        "the recommended cpus supported by KVM (%d)",
                        nc->name, nc->num, soft_vcpus_limit);

            if (nc->num > hard_vcpus_limit) {
                fprintf(stderr, "Number of %s cpus requested (%d) exceeds "
                        "the maximum cpus supported by KVM (%d)\n",
                        nc->name, nc->num, hard_vcpus_limit);
                exit(1);
            }
        }
        nc++;
    }

    missing_cap = kvm_check_extension_list(s, kvm_required_capabilites);
    if (!missing_cap) {
        missing_cap =
            kvm_check_extension_list(s, kvm_arch_required_capabilities);
    }
    if (missing_cap) {
        ret = -EINVAL;
        fprintf(stderr, "kvm does not support %s\n%s",
                missing_cap->name, upgrade_note);
        goto err;
    }

    s->coalesced_mmio = kvm_check_extension(s, KVM_CAP_COALESCED_MMIO);
    s->coalesced_pio = s->coalesced_mmio &&
                       kvm_check_extension(s, KVM_CAP_COALESCED_PIO);

    /*
     * Enable KVM dirty ring if supported, otherwise fall back to
     * dirty logging mode
     */
    if (s->kvm_dirty_ring_size > 0) {
        uint64_t ring_bytes;

        ring_bytes = s->kvm_dirty_ring_size * sizeof(struct kvm_dirty_gfn);

        /* Read the max supported pages */
        ret = kvm_vm_check_extension(s, KVM_CAP_DIRTY_LOG_RING);
        if (ret > 0) {
            if (ring_bytes > ret) {
                error_report("KVM dirty ring size %" PRIu32 " too big "
                             "(maximum is %ld).  Please use a smaller value.",
                             s->kvm_dirty_ring_size,
                             (long)ret / sizeof(struct kvm_dirty_gfn));
                ret = -EINVAL;
                goto err;
            }

            ret = kvm_vm_enable_cap(s, KVM_CAP_DIRTY_LOG_RING, 0, ring_bytes);
            if (ret) {
                error_report("Enabling of KVM dirty ring failed: %s. "
                             "Suggested minimum value is 1024.", strerror(-ret));
                goto err;
            }

            s->kvm_dirty_ring_bytes = ring_bytes;
         } else {
             warn_report("KVM dirty ring not available, using bitmap method");
             s->kvm_dirty_ring_size = 0;
        }
    }

    /*
     * KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 is not needed when dirty ring is
     * enabled.  More importantly, KVM_DIRTY_LOG_INITIALLY_SET will assume no
     * page is wr-protected initially, which is against how kvm dirty ring is
     * usage - kvm dirty ring requires all pages are wr-protected at the very
     * beginning.  Enabling this feature for dirty ring causes data corruption.
     *
     * TODO: Without KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 and kvm clear dirty log,
     * we may expect a higher stall time when starting the migration.  In the
     * future we can enable KVM_CLEAR_DIRTY_LOG to work with dirty ring too:
     * instead of clearing dirty bit, it can be a way to explicitly wr-protect
     * guest pages.
     */
    if (!s->kvm_dirty_ring_size) {
        dirty_log_manual_caps =
            kvm_check_extension(s, KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2);
        dirty_log_manual_caps &= (KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE |
                                  KVM_DIRTY_LOG_INITIALLY_SET);
        s->manual_dirty_log_protect = dirty_log_manual_caps;
        if (dirty_log_manual_caps) {
            ret = kvm_vm_enable_cap(s, KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2, 0,
                                    dirty_log_manual_caps);
            if (ret) {
                warn_report("Trying to enable capability %"PRIu64" of "
                            "KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 but failed. "
                            "Falling back to the legacy mode. ",
                            dirty_log_manual_caps);
                s->manual_dirty_log_protect = 0;
            }
        }
    }

#ifdef KVM_CAP_VCPU_EVENTS
    s->vcpu_events = kvm_check_extension(s, KVM_CAP_VCPU_EVENTS);
#endif

    s->robust_singlestep =
        kvm_check_extension(s, KVM_CAP_X86_ROBUST_SINGLESTEP);

#ifdef KVM_CAP_DEBUGREGS
    s->debugregs = kvm_check_extension(s, KVM_CAP_DEBUGREGS);
#endif

    s->max_nested_state_len = kvm_check_extension(s, KVM_CAP_NESTED_STATE);

#ifdef KVM_CAP_IRQ_ROUTING
    kvm_direct_msi_allowed = (kvm_check_extension(s, KVM_CAP_SIGNAL_MSI) > 0);
#endif

    s->intx_set_mask = kvm_check_extension(s, KVM_CAP_PCI_2_3);

    s->irq_set_ioctl = KVM_IRQ_LINE;
    if (kvm_check_extension(s, KVM_CAP_IRQ_INJECT_STATUS)) {
        s->irq_set_ioctl = KVM_IRQ_LINE_STATUS;
    }

    kvm_readonly_mem_allowed =
        (kvm_check_extension(s, KVM_CAP_READONLY_MEM) > 0);

    kvm_eventfds_allowed =
        (kvm_check_extension(s, KVM_CAP_IOEVENTFD) > 0);

    kvm_irqfds_allowed =
        (kvm_check_extension(s, KVM_CAP_IRQFD) > 0);

    kvm_resamplefds_allowed =
        (kvm_check_extension(s, KVM_CAP_IRQFD_RESAMPLE) > 0);

    kvm_vm_attributes_allowed =
        (kvm_check_extension(s, KVM_CAP_VM_ATTRIBUTES) > 0);

    kvm_ioeventfd_any_length_allowed =
        (kvm_check_extension(s, KVM_CAP_IOEVENTFD_ANY_LENGTH) > 0);

    kvm_state = s;

    ret = kvm_arch_init(ms, s);
    if (ret < 0) {
        goto err;
    }

    if (s->kernel_irqchip_split == ON_OFF_AUTO_AUTO) {
        s->kernel_irqchip_split = mc->default_kernel_irqchip_split ? ON_OFF_AUTO_ON : ON_OFF_AUTO_OFF;
    }

    qemu_register_reset(kvm_unpoison_all, NULL);

    if (s->kernel_irqchip_allowed) {
        kvm_irqchip_create(s);
    }

    if (kvm_eventfds_allowed) {
        s->memory_listener.listener.eventfd_add = kvm_mem_ioeventfd_add;
        s->memory_listener.listener.eventfd_del = kvm_mem_ioeventfd_del;
    }
    s->memory_listener.listener.coalesced_io_add = kvm_coalesce_mmio_region;
    s->memory_listener.listener.coalesced_io_del = kvm_uncoalesce_mmio_region;

    kvm_memory_listener_register(s, &s->memory_listener,
                                 &address_space_memory, 0);
    if (kvm_eventfds_allowed) {
        memory_listener_register(&kvm_io_listener,
                                 &address_space_io);
    }
    memory_listener_register(&kvm_coalesced_pio_listener,
                             &address_space_io);

    s->many_ioeventfds = kvm_check_many_ioeventfds();

    s->sync_mmu = !!kvm_vm_check_extension(kvm_state, KVM_CAP_SYNC_MMU);
    if (!s->sync_mmu) {
        ret = ram_block_discard_disable(true);
        assert(!ret);
    }

    if (s->kvm_dirty_ring_size) {
        ret = kvm_dirty_ring_reaper_init(s);
        if (ret) {
            goto err;
        }
    }

    return 0;

err:
    assert(ret < 0);
    if (s->vmfd >= 0) {
        close(s->vmfd);
    }
    if (s->fd != -1) {
        close(s->fd);
    }
    g_free(s->memory_listener.slots);

    return ret;
}

void kvm_set_sigmask_len(KVMState *s, unsigned int sigmask_len)
{
    s->sigmask_len = sigmask_len;
}

static void kvm_handle_io(uint16_t port, MemTxAttrs attrs, void *data, int direction,
                          int size, uint32_t count)
{
    int i;
    uint8_t *ptr = data;

    for (i = 0; i < count; i++) {
        address_space_rw(&address_space_io, port, attrs,
                         ptr, size,
                         direction == KVM_EXIT_IO_OUT);
        ptr += size;
    }
}

static int kvm_handle_internal_error(CPUState *cpu, struct kvm_run *run)
{
    fprintf(stderr, "KVM internal error. Suberror: %d\n",
            run->internal.suberror);

    if (kvm_check_extension(kvm_state, KVM_CAP_INTERNAL_ERROR_DATA)) {
        int i;

        for (i = 0; i < run->internal.ndata; ++i) {
            fprintf(stderr, "extra data[%d]: 0x%016"PRIx64"\n",
                    i, (uint64_t)run->internal.data[i]);
        }
    }
    if (run->internal.suberror == KVM_INTERNAL_ERROR_EMULATION) {
        fprintf(stderr, "emulation failure\n");
        if (!kvm_arch_stop_on_emulation_error(cpu)) {
            cpu_dump_state(cpu, stderr, CPU_DUMP_CODE);
            return EXCP_INTERRUPT;
        }
    }
    /* FIXME: Should trigger a qmp message to let management know
     * something went wrong.
     */
    return -1;
}

void kvm_flush_coalesced_mmio_buffer(void)
{
    KVMState *s = kvm_state;

    if (s->coalesced_flush_in_progress) {
        return;
    }

    s->coalesced_flush_in_progress = true;

    if (s->coalesced_mmio_ring) {
        struct kvm_coalesced_mmio_ring *ring = s->coalesced_mmio_ring;
        while (ring->first != ring->last) {
            struct kvm_coalesced_mmio *ent;

            ent = &ring->coalesced_mmio[ring->first];

            if (ent->pio == 1) {
                address_space_write(&address_space_io, ent->phys_addr,
                                    MEMTXATTRS_UNSPECIFIED, ent->data,
                                    ent->len);
            } else {
                cpu_physical_memory_write(ent->phys_addr, ent->data, ent->len);
            }
            smp_wmb();
            ring->first = (ring->first + 1) % KVM_COALESCED_MMIO_MAX;
        }
    }

    s->coalesced_flush_in_progress = false;
}

bool kvm_cpu_check_are_resettable(void)
{
    return kvm_arch_cpu_check_are_resettable();
}

static void do_kvm_cpu_synchronize_state(CPUState *cpu, run_on_cpu_data arg)
{
    if (!cpu->vcpu_dirty) {
        kvm_arch_get_registers(cpu);
        cpu->vcpu_dirty = true;
    }
}

void kvm_cpu_synchronize_state(CPUState *cpu)
{
    if (!cpu->vcpu_dirty) {
        run_on_cpu(cpu, do_kvm_cpu_synchronize_state, RUN_ON_CPU_NULL);
    }
}

static void do_kvm_cpu_synchronize_post_reset(CPUState *cpu, run_on_cpu_data arg)
{
    kvm_arch_put_registers(cpu, KVM_PUT_RESET_STATE);
    cpu->vcpu_dirty = false;
}

void kvm_cpu_synchronize_post_reset(CPUState *cpu)
{
    run_on_cpu(cpu, do_kvm_cpu_synchronize_post_reset, RUN_ON_CPU_NULL);
}

static void do_kvm_cpu_synchronize_post_init(CPUState *cpu, run_on_cpu_data arg)
{
    kvm_arch_put_registers(cpu, KVM_PUT_FULL_STATE);
    cpu->vcpu_dirty = false;
}

void kvm_cpu_synchronize_post_init(CPUState *cpu)
{
    run_on_cpu(cpu, do_kvm_cpu_synchronize_post_init, RUN_ON_CPU_NULL);
}

static void do_kvm_cpu_synchronize_pre_loadvm(CPUState *cpu, run_on_cpu_data arg)
{
    cpu->vcpu_dirty = true;
}

void kvm_cpu_synchronize_pre_loadvm(CPUState *cpu)
{
    run_on_cpu(cpu, do_kvm_cpu_synchronize_pre_loadvm, RUN_ON_CPU_NULL);
}

#ifdef KVM_HAVE_MCE_INJECTION
static __thread void *pending_sigbus_addr;
static __thread int pending_sigbus_code;
static __thread bool have_sigbus_pending;
#endif

static void kvm_cpu_kick(CPUState *cpu)
{
    qatomic_set(&cpu->kvm_run->immediate_exit, 1);
}

static void kvm_cpu_kick_self(void)
{
    if (kvm_immediate_exit) {
        kvm_cpu_kick(current_cpu);
    } else {
        qemu_cpu_kick_self();
    }
}

static void kvm_eat_signals(CPUState *cpu)
{
    struct timespec ts = { 0, 0 };
    siginfo_t siginfo;
    sigset_t waitset;
    sigset_t chkset;
    int r;

    if (kvm_immediate_exit) {
        qatomic_set(&cpu->kvm_run->immediate_exit, 0);
        /* Write kvm_run->immediate_exit before the cpu->exit_request
         * write in kvm_cpu_exec.
         */
        smp_wmb();
        return;
    }

    sigemptyset(&waitset);
    sigaddset(&waitset, SIG_IPI);

    do {
        r = sigtimedwait(&waitset, &siginfo, &ts);
        if (r == -1 && !(errno == EAGAIN || errno == EINTR)) {
            perror("sigtimedwait");
            exit(1);
        }

        r = sigpending(&chkset);
        if (r == -1) {
            perror("sigpending");
            exit(1);
        }
    } while (sigismember(&chkset, SIG_IPI));
}

int kvm_cpu_exec(CPUState *cpu)
{
    struct kvm_run *run = cpu->kvm_run;
    int ret, run_ret;

    DPRINTF("kvm_cpu_exec()\n");

    if (kvm_arch_process_async_events(cpu)) {
        qatomic_set(&cpu->exit_request, 0);
        return EXCP_HLT;
    }

    qemu_mutex_unlock_iothread();
    cpu_exec_start(cpu);

    do {
        MemTxAttrs attrs;

        if (cpu->vcpu_dirty) {
            kvm_arch_put_registers(cpu, KVM_PUT_RUNTIME_STATE);
            cpu->vcpu_dirty = false;
        }

        kvm_arch_pre_run(cpu, run);
        if (qatomic_read(&cpu->exit_request)) {
            DPRINTF("interrupt exit requested\n");
            /*
             * KVM requires us to reenter the kernel after IO exits to complete
             * instruction emulation. This self-signal will ensure that we
             * leave ASAP again.
             */
            kvm_cpu_kick_self();
        }

        /* Read cpu->exit_request before KVM_RUN reads run->immediate_exit.
         * Matching barrier in kvm_eat_signals.
         */
        smp_rmb();

        run_ret = kvm_vcpu_ioctl(cpu, KVM_RUN, 0);

        attrs = kvm_arch_post_run(cpu, run);

#ifdef KVM_HAVE_MCE_INJECTION
        if (unlikely(have_sigbus_pending)) {
            qemu_mutex_lock_iothread();
            kvm_arch_on_sigbus_vcpu(cpu, pending_sigbus_code,
                                    pending_sigbus_addr);
            have_sigbus_pending = false;
            qemu_mutex_unlock_iothread();
        }
#endif

        if (run_ret < 0) {
            if (run_ret == -EINTR || run_ret == -EAGAIN) {
                DPRINTF("io window exit\n");
                kvm_eat_signals(cpu);
                ret = EXCP_INTERRUPT;
                break;
            }
            fprintf(stderr, "error: kvm run failed %s\n",
                    strerror(-run_ret));
#ifdef TARGET_PPC
            if (run_ret == -EBUSY) {
                fprintf(stderr,
                        "This is probably because your SMT is enabled.\n"
                        "VCPU can only run on primary threads with all "
                        "secondary threads offline.\n");
            }
#endif
            ret = -1;
            break;
        }

        trace_kvm_run_exit(cpu->cpu_index, run->exit_reason);
        switch (run->exit_reason) {
        case KVM_EXIT_IO:
            DPRINTF("handle_io\n");
            /* Called outside BQL */
            kvm_handle_io(run->io.port, attrs,
                          (uint8_t *)run + run->io.data_offset,
                          run->io.direction,
                          run->io.size,
                          run->io.count);
            ret = 0;
            break;
        case KVM_EXIT_MMIO:
            DPRINTF("handle_mmio\n");
            /* Called outside BQL */
            address_space_rw(&address_space_memory,
                             run->mmio.phys_addr, attrs,
                             run->mmio.data,
                             run->mmio.len,
                             run->mmio.is_write);
            ret = 0;
            break;
        case KVM_EXIT_IRQ_WINDOW_OPEN:
            DPRINTF("irq_window_open\n");
            ret = EXCP_INTERRUPT;
            break;
        case KVM_EXIT_SHUTDOWN:
            DPRINTF("shutdown\n");
            qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
            ret = EXCP_INTERRUPT;
            break;
        case KVM_EXIT_UNKNOWN:
            fprintf(stderr, "KVM: unknown exit, hardware reason %" PRIx64 "\n",
                    (uint64_t)run->hw.hardware_exit_reason);
            ret = -1;
            break;
        case KVM_EXIT_INTERNAL_ERROR:
            ret = kvm_handle_internal_error(cpu, run);
            break;
        case KVM_EXIT_DIRTY_RING_FULL:
            /*
             * We shouldn't continue if the dirty ring of this vcpu is
             * still full.  Got kicked by KVM_RESET_DIRTY_RINGS.
             */
            trace_kvm_dirty_ring_full(cpu->cpu_index);
            qemu_mutex_lock_iothread();
            kvm_dirty_ring_reap(kvm_state);
            qemu_mutex_unlock_iothread();
            ret = 0;
            break;
        case KVM_EXIT_SYSTEM_EVENT:
            switch (run->system_event.type) {
            case KVM_SYSTEM_EVENT_SHUTDOWN:
                qemu_system_shutdown_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
                ret = EXCP_INTERRUPT;
                break;
            case KVM_SYSTEM_EVENT_RESET:
                qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
                ret = EXCP_INTERRUPT;
                break;
            case KVM_SYSTEM_EVENT_CRASH:
                kvm_cpu_synchronize_state(cpu);
                qemu_mutex_lock_iothread();
                qemu_system_guest_panicked(cpu_get_crash_info(cpu));
                qemu_mutex_unlock_iothread();
                ret = 0;
                break;
            default:
                DPRINTF("kvm_arch_handle_exit\n");
                ret = kvm_arch_handle_exit(cpu, run);
                break;
            }
            break;
        default:
            DPRINTF("kvm_arch_handle_exit\n");
            ret = kvm_arch_handle_exit(cpu, run);
            break;
        }
    } while (ret == 0);

    cpu_exec_end(cpu);
    qemu_mutex_lock_iothread();

    if (ret < 0) {
        cpu_dump_state(cpu, stderr, CPU_DUMP_CODE);
        vm_stop(RUN_STATE_INTERNAL_ERROR);
    }

    qatomic_set(&cpu->exit_request, 0);
    return ret;
}

int kvm_ioctl(KVMState *s, int type, ...)
{
    int ret;
    void *arg;
    va_list ap;

    va_start(ap, type);
    arg = va_arg(ap, void *);
    va_end(ap);

    trace_kvm_ioctl(type, arg);
    ret = ioctl(s->fd, type, arg);
    if (ret == -1) {
        ret = -errno;
    }
    return ret;
}

int kvm_vm_ioctl(KVMState *s, int type, ...)
{
    int ret;
    void *arg;
    va_list ap;

    va_start(ap, type);
    arg = va_arg(ap, void *);
    va_end(ap);

    trace_kvm_vm_ioctl(type, arg);
    ret = ioctl(s->vmfd, type, arg);
    if (ret == -1) {
        ret = -errno;
    }
    return ret;
}

int kvm_vcpu_ioctl(CPUState *cpu, int type, ...)
{
    int ret;
    void *arg;
    va_list ap;

    va_start(ap, type);
    arg = va_arg(ap, void *);
    va_end(ap);

    trace_kvm_vcpu_ioctl(cpu->cpu_index, type, arg);
    ret = ioctl(cpu->kvm_fd, type, arg);
    if (ret == -1) {
        ret = -errno;
    }
    return ret;
}

int kvm_device_ioctl(int fd, int type, ...)
{
    int ret;
    void *arg;
    va_list ap;

    va_start(ap, type);
    arg = va_arg(ap, void *);
    va_end(ap);

    trace_kvm_device_ioctl(fd, type, arg);
    ret = ioctl(fd, type, arg);
    if (ret == -1) {
        ret = -errno;
    }
    return ret;
}

int kvm_vm_check_attr(KVMState *s, uint32_t group, uint64_t attr)
{
    int ret;
    struct kvm_device_attr attribute = {
        .group = group,
        .attr = attr,
    };

    if (!kvm_vm_attributes_allowed) {
        return 0;
    }

    ret = kvm_vm_ioctl(s, KVM_HAS_DEVICE_ATTR, &attribute);
    /* kvm returns 0 on success for HAS_DEVICE_ATTR */
    return ret ? 0 : 1;
}

int kvm_device_check_attr(int dev_fd, uint32_t group, uint64_t attr)
{
    struct kvm_device_attr attribute = {
        .group = group,
        .attr = attr,
        .flags = 0,
    };

    return kvm_device_ioctl(dev_fd, KVM_HAS_DEVICE_ATTR, &attribute) ? 0 : 1;
}

int kvm_device_access(int fd, int group, uint64_t attr,
                      void *val, bool write, Error **errp)
{
    struct kvm_device_attr kvmattr;
    int err;

    kvmattr.flags = 0;
    kvmattr.group = group;
    kvmattr.attr = attr;
    kvmattr.addr = (uintptr_t)val;

    err = kvm_device_ioctl(fd,
                           write ? KVM_SET_DEVICE_ATTR : KVM_GET_DEVICE_ATTR,
                           &kvmattr);
    if (err < 0) {
        error_setg_errno(errp, -err,
                         "KVM_%s_DEVICE_ATTR failed: Group %d "
                         "attr 0x%016" PRIx64,
                         write ? "SET" : "GET", group, attr);
    }
    return err;
}

bool kvm_has_sync_mmu(void)
{
    return kvm_state->sync_mmu;
}

int kvm_has_vcpu_events(void)
{
    return kvm_state->vcpu_events;
}

int kvm_has_robust_singlestep(void)
{
    return kvm_state->robust_singlestep;
}

int kvm_has_debugregs(void)
{
    return kvm_state->debugregs;
}

int kvm_max_nested_state_length(void)
{
    return kvm_state->max_nested_state_len;
}

int kvm_has_many_ioeventfds(void)
{
    if (!kvm_enabled()) {
        return 0;
    }
    return kvm_state->many_ioeventfds;
}

int kvm_has_gsi_routing(void)
{
#ifdef KVM_CAP_IRQ_ROUTING
    return kvm_check_extension(kvm_state, KVM_CAP_IRQ_ROUTING);
#else
    return false;
#endif
}

int kvm_has_intx_set_mask(void)
{
    return kvm_state->intx_set_mask;
}

bool kvm_arm_supports_user_irq(void)
{
    return kvm_check_extension(kvm_state, KVM_CAP_ARM_USER_IRQ);
}

#ifdef KVM_CAP_SET_GUEST_DEBUG
struct kvm_sw_breakpoint *kvm_find_sw_breakpoint(CPUState *cpu,
                                                 target_ulong pc)
{
    struct kvm_sw_breakpoint *bp;

    QTAILQ_FOREACH(bp, &cpu->kvm_state->kvm_sw_breakpoints, entry) {
        if (bp->pc == pc) {
            return bp;
        }
    }
    return NULL;
}

int kvm_sw_breakpoints_active(CPUState *cpu)
{
    return !QTAILQ_EMPTY(&cpu->kvm_state->kvm_sw_breakpoints);
}

struct kvm_set_guest_debug_data {
    struct kvm_guest_debug dbg;
    int err;
};

static void kvm_invoke_set_guest_debug(CPUState *cpu, run_on_cpu_data data)
{
    struct kvm_set_guest_debug_data *dbg_data =
        (struct kvm_set_guest_debug_data *) data.host_ptr;

    dbg_data->err = kvm_vcpu_ioctl(cpu, KVM_SET_GUEST_DEBUG,
                                   &dbg_data->dbg);
}

int kvm_update_guest_debug(CPUState *cpu, unsigned long reinject_trap)
{
    struct kvm_set_guest_debug_data data;

    data.dbg.control = reinject_trap;

    if (cpu->singlestep_enabled) {
        data.dbg.control |= KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_SINGLESTEP;
    }
    kvm_arch_update_guest_debug(cpu, &data.dbg);

    run_on_cpu(cpu, kvm_invoke_set_guest_debug,
               RUN_ON_CPU_HOST_PTR(&data));
    return data.err;
}

int kvm_insert_breakpoint(CPUState *cpu, target_ulong addr,
                          target_ulong len, int type)
{
    struct kvm_sw_breakpoint *bp;
    int err;

    if (type == GDB_BREAKPOINT_SW) {
        bp = kvm_find_sw_breakpoint(cpu, addr);
        if (bp) {
            bp->use_count++;
            return 0;
        }

        bp = g_malloc(sizeof(struct kvm_sw_breakpoint));
        bp->pc = addr;
        bp->use_count = 1;
        err = kvm_arch_insert_sw_breakpoint(cpu, bp);
        if (err) {
            g_free(bp);
            return err;
        }

        QTAILQ_INSERT_HEAD(&cpu->kvm_state->kvm_sw_breakpoints, bp, entry);
    } else {
        err = kvm_arch_insert_hw_breakpoint(addr, len, type);
        if (err) {
            return err;
        }
    }

    CPU_FOREACH(cpu) {
        err = kvm_update_guest_debug(cpu, 0);
        if (err) {
            return err;
        }
    }
    return 0;
}

int kvm_remove_breakpoint(CPUState *cpu, target_ulong addr,
                          target_ulong len, int type)
{
    struct kvm_sw_breakpoint *bp;
    int err;

    if (type == GDB_BREAKPOINT_SW) {
        bp = kvm_find_sw_breakpoint(cpu, addr);
        if (!bp) {
            return -ENOENT;
        }

        if (bp->use_count > 1) {
            bp->use_count--;
            return 0;
        }

        err = kvm_arch_remove_sw_breakpoint(cpu, bp);
        if (err) {
            return err;
        }

        QTAILQ_REMOVE(&cpu->kvm_state->kvm_sw_breakpoints, bp, entry);
        g_free(bp);
    } else {
        err = kvm_arch_remove_hw_breakpoint(addr, len, type);
        if (err) {
            return err;
        }
    }

    CPU_FOREACH(cpu) {
        err = kvm_update_guest_debug(cpu, 0);
        if (err) {
            return err;
        }
    }
    return 0;
}

void kvm_remove_all_breakpoints(CPUState *cpu)
{
    struct kvm_sw_breakpoint *bp, *next;
    KVMState *s = cpu->kvm_state;
    CPUState *tmpcpu;

    QTAILQ_FOREACH_SAFE(bp, &s->kvm_sw_breakpoints, entry, next) {
        if (kvm_arch_remove_sw_breakpoint(cpu, bp) != 0) {
            /* Try harder to find a CPU that currently sees the breakpoint. */
            CPU_FOREACH(tmpcpu) {
                if (kvm_arch_remove_sw_breakpoint(tmpcpu, bp) == 0) {
                    break;
                }
            }
        }
        QTAILQ_REMOVE(&s->kvm_sw_breakpoints, bp, entry);
        g_free(bp);
    }
    kvm_arch_remove_all_hw_breakpoints();

    CPU_FOREACH(cpu) {
        kvm_update_guest_debug(cpu, 0);
    }
}

#else /* !KVM_CAP_SET_GUEST_DEBUG */

int kvm_update_guest_debug(CPUState *cpu, unsigned long reinject_trap)
{
    return -EINVAL;
}

int kvm_insert_breakpoint(CPUState *cpu, target_ulong addr,
                          target_ulong len, int type)
{
    return -EINVAL;
}

int kvm_remove_breakpoint(CPUState *cpu, target_ulong addr,
                          target_ulong len, int type)
{
    return -EINVAL;
}

void kvm_remove_all_breakpoints(CPUState *cpu)
{
}
#endif /* !KVM_CAP_SET_GUEST_DEBUG */

static int kvm_set_signal_mask(CPUState *cpu, const sigset_t *sigset)
{
    KVMState *s = kvm_state;
    struct kvm_signal_mask *sigmask;
    int r;

    sigmask = g_malloc(sizeof(*sigmask) + sizeof(*sigset));

    sigmask->len = s->sigmask_len;
    memcpy(sigmask->sigset, sigset, sizeof(*sigset));
    r = kvm_vcpu_ioctl(cpu, KVM_SET_SIGNAL_MASK, sigmask);
    g_free(sigmask);

    return r;
}

static void kvm_ipi_signal(int sig)
{
    if (current_cpu) {
        assert(kvm_immediate_exit);
        kvm_cpu_kick(current_cpu);
    }
}

void kvm_init_cpu_signals(CPUState *cpu)
{
    int r;
    sigset_t set;
    struct sigaction sigact;

    memset(&sigact, 0, sizeof(sigact));
    sigact.sa_handler = kvm_ipi_signal;
    sigaction(SIG_IPI, &sigact, NULL);

    pthread_sigmask(SIG_BLOCK, NULL, &set);
#if defined KVM_HAVE_MCE_INJECTION
    sigdelset(&set, SIGBUS);
    pthread_sigmask(SIG_SETMASK, &set, NULL);
#endif
    sigdelset(&set, SIG_IPI);
    if (kvm_immediate_exit) {
        r = pthread_sigmask(SIG_SETMASK, &set, NULL);
    } else {
        r = kvm_set_signal_mask(cpu, &set);
    }
    if (r) {
        fprintf(stderr, "kvm_set_signal_mask: %s\n", strerror(-r));
        exit(1);
    }
}

/* Called asynchronously in VCPU thread.  */
int kvm_on_sigbus_vcpu(CPUState *cpu, int code, void *addr)
{
#ifdef KVM_HAVE_MCE_INJECTION
    if (have_sigbus_pending) {
        return 1;
    }
    have_sigbus_pending = true;
    pending_sigbus_addr = addr;
    pending_sigbus_code = code;
    qatomic_set(&cpu->exit_request, 1);
    return 0;
#else
    return 1;
#endif
}

/* Called synchronously (via signalfd) in main thread.  */
int kvm_on_sigbus(int code, void *addr)
{
#ifdef KVM_HAVE_MCE_INJECTION
    /* Action required MCE kills the process if SIGBUS is blocked.  Because
     * that's what happens in the I/O thread, where we handle MCE via signalfd,
     * we can only get action optional here.
     */
    assert(code != BUS_MCEERR_AR);
    kvm_arch_on_sigbus_vcpu(first_cpu, code, addr);
    return 0;
#else
    return 1;
#endif
}

int kvm_create_device(KVMState *s, uint64_t type, bool test)
{
    int ret;
    struct kvm_create_device create_dev;

    create_dev.type = type;
    create_dev.fd = -1;
    create_dev.flags = test ? KVM_CREATE_DEVICE_TEST : 0;

    if (!kvm_check_extension(s, KVM_CAP_DEVICE_CTRL)) {
        return -ENOTSUP;
    }

    ret = kvm_vm_ioctl(s, KVM_CREATE_DEVICE, &create_dev);
    if (ret) {
        return ret;
    }

    return test ? 0 : create_dev.fd;
}

bool kvm_device_supported(int vmfd, uint64_t type)
{
    struct kvm_create_device create_dev = {
        .type = type,
        .fd = -1,
        .flags = KVM_CREATE_DEVICE_TEST,
    };

    if (ioctl(vmfd, KVM_CHECK_EXTENSION, KVM_CAP_DEVICE_CTRL) <= 0) {
        return false;
    }

    return (ioctl(vmfd, KVM_CREATE_DEVICE, &create_dev) >= 0);
}

int kvm_set_one_reg(CPUState *cs, uint64_t id, void *source)
{
    struct kvm_one_reg reg;
    int r;

    reg.id = id;
    reg.addr = (uintptr_t) source;
    r = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &reg);
    if (r) {
        trace_kvm_failed_reg_set(id, strerror(-r));
    }
    return r;
}

int kvm_get_one_reg(CPUState *cs, uint64_t id, void *target)
{
    struct kvm_one_reg reg;
    int r;

    reg.id = id;
    reg.addr = (uintptr_t) target;
    r = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &reg);
    if (r) {
        trace_kvm_failed_reg_get(id, strerror(-r));
    }
    return r;
}

static bool kvm_accel_has_memory(MachineState *ms, AddressSpace *as,
                                 hwaddr start_addr, hwaddr size)
{
    KVMState *kvm = KVM_STATE(ms->accelerator);
    int i;

    for (i = 0; i < kvm->nr_as; ++i) {
        if (kvm->as[i].as == as && kvm->as[i].ml) {
            size = MIN(kvm_max_slot_size, size);
            return NULL != kvm_lookup_matching_slot(kvm->as[i].ml,
                                                    start_addr, size);
        }
    }

    return false;
}

static void kvm_get_kvm_shadow_mem(Object *obj, Visitor *v,
                                   const char *name, void *opaque,
                                   Error **errp)
{
    KVMState *s = KVM_STATE(obj);
    int64_t value = s->kvm_shadow_mem;

    visit_type_int(v, name, &value, errp);
}

static void kvm_set_kvm_shadow_mem(Object *obj, Visitor *v,
                                   const char *name, void *opaque,
                                   Error **errp)
{
    KVMState *s = KVM_STATE(obj);
    int64_t value;

    if (s->fd != -1) {
        error_setg(errp, "Cannot set properties after the accelerator has been initialized");
        return;
    }

    if (!visit_type_int(v, name, &value, errp)) {
        return;
    }

    s->kvm_shadow_mem = value;
}

static void kvm_set_kernel_irqchip(Object *obj, Visitor *v,
                                   const char *name, void *opaque,
                                   Error **errp)
{
    KVMState *s = KVM_STATE(obj);
    OnOffSplit mode;

    if (s->fd != -1) {
        error_setg(errp, "Cannot set properties after the accelerator has been initialized");
        return;
    }

    if (!visit_type_OnOffSplit(v, name, &mode, errp)) {
        return;
    }
    switch (mode) {
    case ON_OFF_SPLIT_ON:
        s->kernel_irqchip_allowed = true;
        s->kernel_irqchip_required = true;
        s->kernel_irqchip_split = ON_OFF_AUTO_OFF;
        break;
    case ON_OFF_SPLIT_OFF:
        s->kernel_irqchip_allowed = false;
        s->kernel_irqchip_required = false;
        s->kernel_irqchip_split = ON_OFF_AUTO_OFF;
        break;
    case ON_OFF_SPLIT_SPLIT:
        s->kernel_irqchip_allowed = true;
        s->kernel_irqchip_required = true;
        s->kernel_irqchip_split = ON_OFF_AUTO_ON;
        break;
    default:
        /* The value was checked in visit_type_OnOffSplit() above. If
         * we get here, then something is wrong in QEMU.
         */
        abort();
    }
}

bool kvm_kernel_irqchip_allowed(void)
{
    return kvm_state->kernel_irqchip_allowed;
}

bool kvm_kernel_irqchip_required(void)
{
    return kvm_state->kernel_irqchip_required;
}

bool kvm_kernel_irqchip_split(void)
{
    return kvm_state->kernel_irqchip_split == ON_OFF_AUTO_ON;
}

static void kvm_get_dirty_ring_size(Object *obj, Visitor *v,
                                    const char *name, void *opaque,
                                    Error **errp)
{
    KVMState *s = KVM_STATE(obj);
    uint32_t value = s->kvm_dirty_ring_size;

    visit_type_uint32(v, name, &value, errp);
}

static void kvm_set_dirty_ring_size(Object *obj, Visitor *v,
                                    const char *name, void *opaque,
                                    Error **errp)
{
    KVMState *s = KVM_STATE(obj);
    Error *error = NULL;
    uint32_t value;

    if (s->fd != -1) {
        error_setg(errp, "Cannot set properties after the accelerator has been initialized");
        return;
    }

    visit_type_uint32(v, name, &value, &error);
    if (error) {
        error_propagate(errp, error);
        return;
    }
    if (value & (value - 1)) {
        error_setg(errp, "dirty-ring-size must be a power of two.");
        return;
    }

    s->kvm_dirty_ring_size = value;
}

static void kvm_accel_instance_init(Object *obj)
{
    KVMState *s = KVM_STATE(obj);

    s->fd = -1;
    s->vmfd = -1;
    s->kvm_shadow_mem = -1;
    s->kernel_irqchip_allowed = true;
    s->kernel_irqchip_split = ON_OFF_AUTO_AUTO;
    /* KVM dirty ring is by default off */
    s->kvm_dirty_ring_size = 0;
}

static void kvm_accel_class_init(ObjectClass *oc, void *data)
{
    AccelClass *ac = ACCEL_CLASS(oc);
    ac->name = "KVM";
    ac->init_machine = kvm_init;
    ac->has_memory = kvm_accel_has_memory;
    ac->allowed = &kvm_allowed;

    object_class_property_add(oc, "kernel-irqchip", "on|off|split",
        NULL, kvm_set_kernel_irqchip,
        NULL, NULL);
    object_class_property_set_description(oc, "kernel-irqchip",
        "Configure KVM in-kernel irqchip");

    object_class_property_add(oc, "kvm-shadow-mem", "int",
        kvm_get_kvm_shadow_mem, kvm_set_kvm_shadow_mem,
        NULL, NULL);
    object_class_property_set_description(oc, "kvm-shadow-mem",
        "KVM shadow MMU size");

    object_class_property_add(oc, "dirty-ring-size", "uint32",
        kvm_get_dirty_ring_size, kvm_set_dirty_ring_size,
        NULL, NULL);
    object_class_property_set_description(oc, "dirty-ring-size",
        "Size of KVM dirty page ring buffer (default: 0, i.e. use bitmap)");
}

static const TypeInfo kvm_accel_type = {
    .name = TYPE_KVM_ACCEL,
    .parent = TYPE_ACCEL,
    .instance_init = kvm_accel_instance_init,
    .class_init = kvm_accel_class_init,
    .instance_size = sizeof(KVMState),
};

static void kvm_type_init(void)
{
    type_register_static(&kvm_accel_type);
}

type_init(kvm_type_init);