summaryrefslogtreecommitdiff
path: root/drivers/s390/crypto/vfio_ap_ops.c
blob: 6c8c41fac4e14f60f9fa542dbed8434a18b39198 (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
// SPDX-License-Identifier: GPL-2.0+
/*
 * Adjunct processor matrix VFIO device driver callbacks.
 *
 * Copyright IBM Corp. 2018
 *
 * Author(s): Tony Krowiak <akrowiak@linux.ibm.com>
 *	      Halil Pasic <pasic@linux.ibm.com>
 *	      Pierre Morel <pmorel@linux.ibm.com>
 */
#include <linux/string.h>
#include <linux/vfio.h>
#include <linux/device.h>
#include <linux/list.h>
#include <linux/ctype.h>
#include <linux/bitops.h>
#include <linux/kvm_host.h>
#include <linux/module.h>
#include <linux/uuid.h>
#include <asm/kvm.h>
#include <asm/zcrypt.h>

#include "vfio_ap_private.h"
#include "vfio_ap_debug.h"

#define VFIO_AP_MDEV_TYPE_HWVIRT "passthrough"
#define VFIO_AP_MDEV_NAME_HWVIRT "VFIO AP Passthrough Device"

#define AP_QUEUE_ASSIGNED "assigned"
#define AP_QUEUE_UNASSIGNED "unassigned"
#define AP_QUEUE_IN_USE "in use"

static int vfio_ap_mdev_reset_queues(struct ap_queue_table *qtable);
static struct vfio_ap_queue *vfio_ap_find_queue(int apqn);
static const struct vfio_device_ops vfio_ap_matrix_dev_ops;
static int vfio_ap_mdev_reset_queue(struct vfio_ap_queue *q, unsigned int retry);

/**
 * get_update_locks_for_kvm: Acquire the locks required to dynamically update a
 *			     KVM guest's APCB in the proper order.
 *
 * @kvm: a pointer to a struct kvm object containing the KVM guest's APCB.
 *
 * The proper locking order is:
 * 1. matrix_dev->guests_lock: required to use the KVM pointer to update a KVM
 *			       guest's APCB.
 * 2. kvm->lock:	       required to update a guest's APCB
 * 3. matrix_dev->mdevs_lock:  required to access data stored in a matrix_mdev
 *
 * Note: If @kvm is NULL, the KVM lock will not be taken.
 */
static inline void get_update_locks_for_kvm(struct kvm *kvm)
{
	mutex_lock(&matrix_dev->guests_lock);
	if (kvm)
		mutex_lock(&kvm->lock);
	mutex_lock(&matrix_dev->mdevs_lock);
}

/**
 * release_update_locks_for_kvm: Release the locks used to dynamically update a
 *				 KVM guest's APCB in the proper order.
 *
 * @kvm: a pointer to a struct kvm object containing the KVM guest's APCB.
 *
 * The proper unlocking order is:
 * 1. matrix_dev->mdevs_lock
 * 2. kvm->lock
 * 3. matrix_dev->guests_lock
 *
 * Note: If @kvm is NULL, the KVM lock will not be released.
 */
static inline void release_update_locks_for_kvm(struct kvm *kvm)
{
	mutex_unlock(&matrix_dev->mdevs_lock);
	if (kvm)
		mutex_unlock(&kvm->lock);
	mutex_unlock(&matrix_dev->guests_lock);
}

/**
 * get_update_locks_for_mdev: Acquire the locks required to dynamically update a
 *			      KVM guest's APCB in the proper order.
 *
 * @matrix_mdev: a pointer to a struct ap_matrix_mdev object containing the AP
 *		 configuration data to use to update a KVM guest's APCB.
 *
 * The proper locking order is:
 * 1. matrix_dev->guests_lock: required to use the KVM pointer to update a KVM
 *			       guest's APCB.
 * 2. matrix_mdev->kvm->lock:  required to update a guest's APCB
 * 3. matrix_dev->mdevs_lock:  required to access data stored in a matrix_mdev
 *
 * Note: If @matrix_mdev is NULL or is not attached to a KVM guest, the KVM
 *	 lock will not be taken.
 */
static inline void get_update_locks_for_mdev(struct ap_matrix_mdev *matrix_mdev)
{
	mutex_lock(&matrix_dev->guests_lock);
	if (matrix_mdev && matrix_mdev->kvm)
		mutex_lock(&matrix_mdev->kvm->lock);
	mutex_lock(&matrix_dev->mdevs_lock);
}

/**
 * release_update_locks_for_mdev: Release the locks used to dynamically update a
 *				  KVM guest's APCB in the proper order.
 *
 * @matrix_mdev: a pointer to a struct ap_matrix_mdev object containing the AP
 *		 configuration data to use to update a KVM guest's APCB.
 *
 * The proper unlocking order is:
 * 1. matrix_dev->mdevs_lock
 * 2. matrix_mdev->kvm->lock
 * 3. matrix_dev->guests_lock
 *
 * Note: If @matrix_mdev is NULL or is not attached to a KVM guest, the KVM
 *	 lock will not be released.
 */
static inline void release_update_locks_for_mdev(struct ap_matrix_mdev *matrix_mdev)
{
	mutex_unlock(&matrix_dev->mdevs_lock);
	if (matrix_mdev && matrix_mdev->kvm)
		mutex_unlock(&matrix_mdev->kvm->lock);
	mutex_unlock(&matrix_dev->guests_lock);
}

/**
 * get_update_locks_by_apqn: Find the mdev to which an APQN is assigned and
 *			     acquire the locks required to update the APCB of
 *			     the KVM guest to which the mdev is attached.
 *
 * @apqn: the APQN of a queue device.
 *
 * The proper locking order is:
 * 1. matrix_dev->guests_lock: required to use the KVM pointer to update a KVM
 *			       guest's APCB.
 * 2. matrix_mdev->kvm->lock:  required to update a guest's APCB
 * 3. matrix_dev->mdevs_lock:  required to access data stored in a matrix_mdev
 *
 * Note: If @apqn is not assigned to a matrix_mdev, the matrix_mdev->kvm->lock
 *	 will not be taken.
 *
 * Return: the ap_matrix_mdev object to which @apqn is assigned or NULL if @apqn
 *	   is not assigned to an ap_matrix_mdev.
 */
static struct ap_matrix_mdev *get_update_locks_by_apqn(int apqn)
{
	struct ap_matrix_mdev *matrix_mdev;

	mutex_lock(&matrix_dev->guests_lock);

	list_for_each_entry(matrix_mdev, &matrix_dev->mdev_list, node) {
		if (test_bit_inv(AP_QID_CARD(apqn), matrix_mdev->matrix.apm) &&
		    test_bit_inv(AP_QID_QUEUE(apqn), matrix_mdev->matrix.aqm)) {
			if (matrix_mdev->kvm)
				mutex_lock(&matrix_mdev->kvm->lock);

			mutex_lock(&matrix_dev->mdevs_lock);

			return matrix_mdev;
		}
	}

	mutex_lock(&matrix_dev->mdevs_lock);

	return NULL;
}

/**
 * get_update_locks_for_queue: get the locks required to update the APCB of the
 *			       KVM guest to which the matrix mdev linked to a
 *			       vfio_ap_queue object is attached.
 *
 * @q: a pointer to a vfio_ap_queue object.
 *
 * The proper locking order is:
 * 1. q->matrix_dev->guests_lock: required to use the KVM pointer to update a
 *				  KVM guest's APCB.
 * 2. q->matrix_mdev->kvm->lock:  required to update a guest's APCB
 * 3. matrix_dev->mdevs_lock:	  required to access data stored in matrix_mdev
 *
 * Note: if @queue is not linked to an ap_matrix_mdev object, the KVM lock
 *	  will not be taken.
 */
static inline void get_update_locks_for_queue(struct vfio_ap_queue *q)
{
	mutex_lock(&matrix_dev->guests_lock);
	if (q->matrix_mdev && q->matrix_mdev->kvm)
		mutex_lock(&q->matrix_mdev->kvm->lock);
	mutex_lock(&matrix_dev->mdevs_lock);
}

/**
 * vfio_ap_mdev_get_queue - retrieve a queue with a specific APQN from a
 *			    hash table of queues assigned to a matrix mdev
 * @matrix_mdev: the matrix mdev
 * @apqn: The APQN of a queue device
 *
 * Return: the pointer to the vfio_ap_queue struct representing the queue or
 *	   NULL if the queue is not assigned to @matrix_mdev
 */
static struct vfio_ap_queue *vfio_ap_mdev_get_queue(
					struct ap_matrix_mdev *matrix_mdev,
					int apqn)
{
	struct vfio_ap_queue *q;

	hash_for_each_possible(matrix_mdev->qtable.queues, q, mdev_qnode,
			       apqn) {
		if (q && q->apqn == apqn)
			return q;
	}

	return NULL;
}

/**
 * vfio_ap_wait_for_irqclear - clears the IR bit or gives up after 5 tries
 * @apqn: The AP Queue number
 *
 * Checks the IRQ bit for the status of this APQN using ap_tapq.
 * Returns if the ap_tapq function succeeded and the bit is clear.
 * Returns if ap_tapq function failed with invalid, deconfigured or
 * checkstopped AP.
 * Otherwise retries up to 5 times after waiting 20ms.
 */
static void vfio_ap_wait_for_irqclear(int apqn)
{
	struct ap_queue_status status;
	int retry = 5;

	do {
		status = ap_tapq(apqn, NULL);
		switch (status.response_code) {
		case AP_RESPONSE_NORMAL:
		case AP_RESPONSE_RESET_IN_PROGRESS:
			if (!status.irq_enabled)
				return;
			fallthrough;
		case AP_RESPONSE_BUSY:
			msleep(20);
			break;
		case AP_RESPONSE_Q_NOT_AVAIL:
		case AP_RESPONSE_DECONFIGURED:
		case AP_RESPONSE_CHECKSTOPPED:
		default:
			WARN_ONCE(1, "%s: tapq rc %02x: %04x\n", __func__,
				  status.response_code, apqn);
			return;
		}
	} while (--retry);

	WARN_ONCE(1, "%s: tapq rc %02x: %04x could not clear IR bit\n",
		  __func__, status.response_code, apqn);
}

/**
 * vfio_ap_free_aqic_resources - free vfio_ap_queue resources
 * @q: The vfio_ap_queue
 *
 * Unregisters the ISC in the GIB when the saved ISC not invalid.
 * Unpins the guest's page holding the NIB when it exists.
 * Resets the saved_iova and saved_isc to invalid values.
 */
static void vfio_ap_free_aqic_resources(struct vfio_ap_queue *q)
{
	if (!q)
		return;
	if (q->saved_isc != VFIO_AP_ISC_INVALID &&
	    !WARN_ON(!(q->matrix_mdev && q->matrix_mdev->kvm))) {
		kvm_s390_gisc_unregister(q->matrix_mdev->kvm, q->saved_isc);
		q->saved_isc = VFIO_AP_ISC_INVALID;
	}
	if (q->saved_iova && !WARN_ON(!q->matrix_mdev)) {
		vfio_unpin_pages(&q->matrix_mdev->vdev, q->saved_iova, 1);
		q->saved_iova = 0;
	}
}

/**
 * vfio_ap_irq_disable - disables and clears an ap_queue interrupt
 * @q: The vfio_ap_queue
 *
 * Uses ap_aqic to disable the interruption and in case of success, reset
 * in progress or IRQ disable command already proceeded: calls
 * vfio_ap_wait_for_irqclear() to check for the IRQ bit to be clear
 * and calls vfio_ap_free_aqic_resources() to free the resources associated
 * with the AP interrupt handling.
 *
 * In the case the AP is busy, or a reset is in progress,
 * retries after 20ms, up to 5 times.
 *
 * Returns if ap_aqic function failed with invalid, deconfigured or
 * checkstopped AP.
 *
 * Return: &struct ap_queue_status
 */
static struct ap_queue_status vfio_ap_irq_disable(struct vfio_ap_queue *q)
{
	struct ap_qirq_ctrl aqic_gisa = {};
	struct ap_queue_status status;
	int retries = 5;

	do {
		status = ap_aqic(q->apqn, aqic_gisa, 0);
		switch (status.response_code) {
		case AP_RESPONSE_OTHERWISE_CHANGED:
		case AP_RESPONSE_NORMAL:
			vfio_ap_wait_for_irqclear(q->apqn);
			goto end_free;
		case AP_RESPONSE_RESET_IN_PROGRESS:
		case AP_RESPONSE_BUSY:
			msleep(20);
			break;
		case AP_RESPONSE_Q_NOT_AVAIL:
		case AP_RESPONSE_DECONFIGURED:
		case AP_RESPONSE_CHECKSTOPPED:
		case AP_RESPONSE_INVALID_ADDRESS:
		default:
			/* All cases in default means AP not operational */
			WARN_ONCE(1, "%s: ap_aqic status %d\n", __func__,
				  status.response_code);
			goto end_free;
		}
	} while (retries--);

	WARN_ONCE(1, "%s: ap_aqic status %d\n", __func__,
		  status.response_code);
end_free:
	vfio_ap_free_aqic_resources(q);
	return status;
}

/**
 * vfio_ap_validate_nib - validate a notification indicator byte (nib) address.
 *
 * @vcpu: the object representing the vcpu executing the PQAP(AQIC) instruction.
 * @nib: the location for storing the nib address.
 *
 * When the PQAP(AQIC) instruction is executed, general register 2 contains the
 * address of the notification indicator byte (nib) used for IRQ notification.
 * This function parses and validates the nib from gr2.
 *
 * Return: returns zero if the nib address is a valid; otherwise, returns
 *	   -EINVAL.
 */
static int vfio_ap_validate_nib(struct kvm_vcpu *vcpu, dma_addr_t *nib)
{
	*nib = vcpu->run->s.regs.gprs[2];

	if (kvm_is_error_hva(gfn_to_hva(vcpu->kvm, *nib >> PAGE_SHIFT)))
		return -EINVAL;

	return 0;
}

/**
 * vfio_ap_irq_enable - Enable Interruption for a APQN
 *
 * @q:	 the vfio_ap_queue holding AQIC parameters
 * @isc: the guest ISC to register with the GIB interface
 * @vcpu: the vcpu object containing the registers specifying the parameters
 *	  passed to the PQAP(AQIC) instruction.
 *
 * Pin the NIB saved in *q
 * Register the guest ISC to GIB interface and retrieve the
 * host ISC to issue the host side PQAP/AQIC
 *
 * Response.status may be set to AP_RESPONSE_INVALID_ADDRESS in case the
 * vfio_pin_pages failed.
 *
 * Otherwise return the ap_queue_status returned by the ap_aqic(),
 * all retry handling will be done by the guest.
 *
 * Return: &struct ap_queue_status
 */
static struct ap_queue_status vfio_ap_irq_enable(struct vfio_ap_queue *q,
						 int isc,
						 struct kvm_vcpu *vcpu)
{
	struct ap_qirq_ctrl aqic_gisa = {};
	struct ap_queue_status status = {};
	struct kvm_s390_gisa *gisa;
	struct page *h_page;
	int nisc;
	struct kvm *kvm;
	phys_addr_t h_nib;
	dma_addr_t nib;
	int ret;

	/* Verify that the notification indicator byte address is valid */
	if (vfio_ap_validate_nib(vcpu, &nib)) {
		VFIO_AP_DBF_WARN("%s: invalid NIB address: nib=%pad, apqn=%#04x\n",
				 __func__, &nib, q->apqn);

		status.response_code = AP_RESPONSE_INVALID_ADDRESS;
		return status;
	}

	ret = vfio_pin_pages(&q->matrix_mdev->vdev, nib, 1,
			     IOMMU_READ | IOMMU_WRITE, &h_page);
	switch (ret) {
	case 1:
		break;
	default:
		VFIO_AP_DBF_WARN("%s: vfio_pin_pages failed: rc=%d,"
				 "nib=%pad, apqn=%#04x\n",
				 __func__, ret, &nib, q->apqn);

		status.response_code = AP_RESPONSE_INVALID_ADDRESS;
		return status;
	}

	kvm = q->matrix_mdev->kvm;
	gisa = kvm->arch.gisa_int.origin;

	h_nib = page_to_phys(h_page) | (nib & ~PAGE_MASK);
	aqic_gisa.gisc = isc;

	nisc = kvm_s390_gisc_register(kvm, isc);
	if (nisc < 0) {
		VFIO_AP_DBF_WARN("%s: gisc registration failed: nisc=%d, isc=%d, apqn=%#04x\n",
				 __func__, nisc, isc, q->apqn);

		status.response_code = AP_RESPONSE_INVALID_GISA;
		return status;
	}

	aqic_gisa.isc = nisc;
	aqic_gisa.ir = 1;
	aqic_gisa.gisa = (uint64_t)gisa >> 4;

	status = ap_aqic(q->apqn, aqic_gisa, h_nib);
	switch (status.response_code) {
	case AP_RESPONSE_NORMAL:
		/* See if we did clear older IRQ configuration */
		vfio_ap_free_aqic_resources(q);
		q->saved_iova = nib;
		q->saved_isc = isc;
		break;
	case AP_RESPONSE_OTHERWISE_CHANGED:
		/* We could not modify IRQ setings: clear new configuration */
		vfio_unpin_pages(&q->matrix_mdev->vdev, nib, 1);
		kvm_s390_gisc_unregister(kvm, isc);
		break;
	default:
		pr_warn("%s: apqn %04x: response: %02x\n", __func__, q->apqn,
			status.response_code);
		vfio_ap_irq_disable(q);
		break;
	}

	if (status.response_code != AP_RESPONSE_NORMAL) {
		VFIO_AP_DBF_WARN("%s: PQAP(AQIC) failed with status=%#02x: "
				 "zone=%#x, ir=%#x, gisc=%#x, f=%#x,"
				 "gisa=%#x, isc=%#x, apqn=%#04x\n",
				 __func__, status.response_code,
				 aqic_gisa.zone, aqic_gisa.ir, aqic_gisa.gisc,
				 aqic_gisa.gf, aqic_gisa.gisa, aqic_gisa.isc,
				 q->apqn);
	}

	return status;
}

/**
 * vfio_ap_le_guid_to_be_uuid - convert a little endian guid array into an array
 *				of big endian elements that can be passed by
 *				value to an s390dbf sprintf event function to
 *				format a UUID string.
 *
 * @guid: the object containing the little endian guid
 * @uuid: a six-element array of long values that can be passed by value as
 *	  arguments for a formatting string specifying a UUID.
 *
 * The S390 Debug Feature (s390dbf) allows the use of "%s" in the sprintf
 * event functions if the memory for the passed string is available as long as
 * the debug feature exists. Since a mediated device can be removed at any
 * time, it's name can not be used because %s passes the reference to the string
 * in memory and the reference will go stale once the device is removed .
 *
 * The s390dbf string formatting function allows a maximum of 9 arguments for a
 * message to be displayed in the 'sprintf' view. In order to use the bytes
 * comprising the mediated device's UUID to display the mediated device name,
 * they will have to be converted into an array whose elements can be passed by
 * value to sprintf. For example:
 *
 * guid array: { 83, 78, 17, 62, bb, f1, f0, 47, 91, 4d, 32, a2, 2e, 3a, 88, 04 }
 * mdev name: 62177883-f1bb-47f0-914d-32a22e3a8804
 * array returned: { 62177883, f1bb, 47f0, 914d, 32a2, 2e3a8804 }
 * formatting string: "%08lx-%04lx-%04lx-%04lx-%02lx%04lx"
 */
static void vfio_ap_le_guid_to_be_uuid(guid_t *guid, unsigned long *uuid)
{
	/*
	 * The input guid is ordered in little endian, so it needs to be
	 * reordered for displaying a UUID as a string. This specifies the
	 * guid indices in proper order.
	 */
	uuid[0] = le32_to_cpup((__le32 *)guid);
	uuid[1] = le16_to_cpup((__le16 *)&guid->b[4]);
	uuid[2] = le16_to_cpup((__le16 *)&guid->b[6]);
	uuid[3] = *((__u16 *)&guid->b[8]);
	uuid[4] = *((__u16 *)&guid->b[10]);
	uuid[5] = *((__u32 *)&guid->b[12]);
}

/**
 * handle_pqap - PQAP instruction callback
 *
 * @vcpu: The vcpu on which we received the PQAP instruction
 *
 * Get the general register contents to initialize internal variables.
 * REG[0]: APQN
 * REG[1]: IR and ISC
 * REG[2]: NIB
 *
 * Response.status may be set to following Response Code:
 * - AP_RESPONSE_Q_NOT_AVAIL: if the queue is not available
 * - AP_RESPONSE_DECONFIGURED: if the queue is not configured
 * - AP_RESPONSE_NORMAL (0) : in case of successs
 *   Check vfio_ap_setirq() and vfio_ap_clrirq() for other possible RC.
 * We take the matrix_dev lock to ensure serialization on queues and
 * mediated device access.
 *
 * Return: 0 if we could handle the request inside KVM.
 * Otherwise, returns -EOPNOTSUPP to let QEMU handle the fault.
 */
static int handle_pqap(struct kvm_vcpu *vcpu)
{
	uint64_t status;
	uint16_t apqn;
	unsigned long uuid[6];
	struct vfio_ap_queue *q;
	struct ap_queue_status qstatus = {
			       .response_code = AP_RESPONSE_Q_NOT_AVAIL, };
	struct ap_matrix_mdev *matrix_mdev;

	apqn = vcpu->run->s.regs.gprs[0] & 0xffff;

	/* If we do not use the AIV facility just go to userland */
	if (!(vcpu->arch.sie_block->eca & ECA_AIV)) {
		VFIO_AP_DBF_WARN("%s: AIV facility not installed: apqn=0x%04x, eca=0x%04x\n",
				 __func__, apqn, vcpu->arch.sie_block->eca);

		return -EOPNOTSUPP;
	}

	mutex_lock(&matrix_dev->mdevs_lock);

	if (!vcpu->kvm->arch.crypto.pqap_hook) {
		VFIO_AP_DBF_WARN("%s: PQAP(AQIC) hook not registered with the vfio_ap driver: apqn=0x%04x\n",
				 __func__, apqn);

		goto out_unlock;
	}

	matrix_mdev = container_of(vcpu->kvm->arch.crypto.pqap_hook,
				   struct ap_matrix_mdev, pqap_hook);

	/* If the there is no guest using the mdev, there is nothing to do */
	if (!matrix_mdev->kvm) {
		vfio_ap_le_guid_to_be_uuid(&matrix_mdev->mdev->uuid, uuid);
		VFIO_AP_DBF_WARN("%s: mdev %08lx-%04lx-%04lx-%04lx-%04lx%08lx not in use: apqn=0x%04x\n",
				 __func__, uuid[0],  uuid[1], uuid[2],
				 uuid[3], uuid[4], uuid[5], apqn);
		goto out_unlock;
	}

	q = vfio_ap_mdev_get_queue(matrix_mdev, apqn);
	if (!q) {
		VFIO_AP_DBF_WARN("%s: Queue %02x.%04x not bound to the vfio_ap driver\n",
				 __func__, AP_QID_CARD(apqn),
				 AP_QID_QUEUE(apqn));
		goto out_unlock;
	}

	status = vcpu->run->s.regs.gprs[1];

	/* If IR bit(16) is set we enable the interrupt */
	if ((status >> (63 - 16)) & 0x01)
		qstatus = vfio_ap_irq_enable(q, status & 0x07, vcpu);
	else
		qstatus = vfio_ap_irq_disable(q);

out_unlock:
	memcpy(&vcpu->run->s.regs.gprs[1], &qstatus, sizeof(qstatus));
	vcpu->run->s.regs.gprs[1] >>= 32;
	mutex_unlock(&matrix_dev->mdevs_lock);
	return 0;
}

static void vfio_ap_matrix_init(struct ap_config_info *info,
				struct ap_matrix *matrix)
{
	matrix->apm_max = info->apxa ? info->Na : 63;
	matrix->aqm_max = info->apxa ? info->Nd : 15;
	matrix->adm_max = info->apxa ? info->Nd : 15;
}

static void vfio_ap_mdev_update_guest_apcb(struct ap_matrix_mdev *matrix_mdev)
{
	if (matrix_mdev->kvm)
		kvm_arch_crypto_set_masks(matrix_mdev->kvm,
					  matrix_mdev->shadow_apcb.apm,
					  matrix_mdev->shadow_apcb.aqm,
					  matrix_mdev->shadow_apcb.adm);
}

static bool vfio_ap_mdev_filter_cdoms(struct ap_matrix_mdev *matrix_mdev)
{
	DECLARE_BITMAP(prev_shadow_adm, AP_DOMAINS);

	bitmap_copy(prev_shadow_adm, matrix_mdev->shadow_apcb.adm, AP_DOMAINS);
	bitmap_and(matrix_mdev->shadow_apcb.adm, matrix_mdev->matrix.adm,
		   (unsigned long *)matrix_dev->info.adm, AP_DOMAINS);

	return !bitmap_equal(prev_shadow_adm, matrix_mdev->shadow_apcb.adm,
			     AP_DOMAINS);
}

/*
 * vfio_ap_mdev_filter_matrix - filter the APQNs assigned to the matrix mdev
 *				to ensure no queue devices are passed through to
 *				the guest that are not bound to the vfio_ap
 *				device driver.
 *
 * @matrix_mdev: the matrix mdev whose matrix is to be filtered.
 *
 * Note: If an APQN referencing a queue device that is not bound to the vfio_ap
 *	 driver, its APID will be filtered from the guest's APCB. The matrix
 *	 structure precludes filtering an individual APQN, so its APID will be
 *	 filtered.
 *
 * Return: a boolean value indicating whether the KVM guest's APCB was changed
 *	   by the filtering or not.
 */
static bool vfio_ap_mdev_filter_matrix(unsigned long *apm, unsigned long *aqm,
				       struct ap_matrix_mdev *matrix_mdev)
{
	unsigned long apid, apqi, apqn;
	DECLARE_BITMAP(prev_shadow_apm, AP_DEVICES);
	DECLARE_BITMAP(prev_shadow_aqm, AP_DOMAINS);
	struct vfio_ap_queue *q;

	bitmap_copy(prev_shadow_apm, matrix_mdev->shadow_apcb.apm, AP_DEVICES);
	bitmap_copy(prev_shadow_aqm, matrix_mdev->shadow_apcb.aqm, AP_DOMAINS);
	vfio_ap_matrix_init(&matrix_dev->info, &matrix_mdev->shadow_apcb);

	/*
	 * Copy the adapters, domains and control domains to the shadow_apcb
	 * from the matrix mdev, but only those that are assigned to the host's
	 * AP configuration.
	 */
	bitmap_and(matrix_mdev->shadow_apcb.apm, matrix_mdev->matrix.apm,
		   (unsigned long *)matrix_dev->info.apm, AP_DEVICES);
	bitmap_and(matrix_mdev->shadow_apcb.aqm, matrix_mdev->matrix.aqm,
		   (unsigned long *)matrix_dev->info.aqm, AP_DOMAINS);

	for_each_set_bit_inv(apid, apm, AP_DEVICES) {
		for_each_set_bit_inv(apqi, aqm, AP_DOMAINS) {
			/*
			 * If the APQN is not bound to the vfio_ap device
			 * driver, then we can't assign it to the guest's
			 * AP configuration. The AP architecture won't
			 * allow filtering of a single APQN, so let's filter
			 * the APID since an adapter represents a physical
			 * hardware device.
			 */
			apqn = AP_MKQID(apid, apqi);
			q = vfio_ap_mdev_get_queue(matrix_mdev, apqn);
			if (!q || q->reset_rc) {
				clear_bit_inv(apid,
					      matrix_mdev->shadow_apcb.apm);
				break;
			}
		}
	}

	return !bitmap_equal(prev_shadow_apm, matrix_mdev->shadow_apcb.apm,
			     AP_DEVICES) ||
	       !bitmap_equal(prev_shadow_aqm, matrix_mdev->shadow_apcb.aqm,
			     AP_DOMAINS);
}

static int vfio_ap_mdev_probe(struct mdev_device *mdev)
{
	struct ap_matrix_mdev *matrix_mdev;
	int ret;

	if ((atomic_dec_if_positive(&matrix_dev->available_instances) < 0))
		return -EPERM;

	matrix_mdev = kzalloc(sizeof(*matrix_mdev), GFP_KERNEL);
	if (!matrix_mdev) {
		ret = -ENOMEM;
		goto err_dec_available;
	}
	vfio_init_group_dev(&matrix_mdev->vdev, &mdev->dev,
			    &vfio_ap_matrix_dev_ops);

	matrix_mdev->mdev = mdev;
	vfio_ap_matrix_init(&matrix_dev->info, &matrix_mdev->matrix);
	matrix_mdev->pqap_hook = handle_pqap;
	vfio_ap_matrix_init(&matrix_dev->info, &matrix_mdev->shadow_apcb);
	hash_init(matrix_mdev->qtable.queues);

	ret = vfio_register_emulated_iommu_dev(&matrix_mdev->vdev);
	if (ret)
		goto err_list;
	dev_set_drvdata(&mdev->dev, matrix_mdev);
	mutex_lock(&matrix_dev->mdevs_lock);
	list_add(&matrix_mdev->node, &matrix_dev->mdev_list);
	mutex_unlock(&matrix_dev->mdevs_lock);
	return 0;

err_list:
	vfio_uninit_group_dev(&matrix_mdev->vdev);
	kfree(matrix_mdev);
err_dec_available:
	atomic_inc(&matrix_dev->available_instances);
	return ret;
}

static void vfio_ap_mdev_link_queue(struct ap_matrix_mdev *matrix_mdev,
				    struct vfio_ap_queue *q)
{
	if (q) {
		q->matrix_mdev = matrix_mdev;
		hash_add(matrix_mdev->qtable.queues, &q->mdev_qnode, q->apqn);
	}
}

static void vfio_ap_mdev_link_apqn(struct ap_matrix_mdev *matrix_mdev, int apqn)
{
	struct vfio_ap_queue *q;

	q = vfio_ap_find_queue(apqn);
	vfio_ap_mdev_link_queue(matrix_mdev, q);
}

static void vfio_ap_unlink_queue_fr_mdev(struct vfio_ap_queue *q)
{
	hash_del(&q->mdev_qnode);
}

static void vfio_ap_unlink_mdev_fr_queue(struct vfio_ap_queue *q)
{
	q->matrix_mdev = NULL;
}

static void vfio_ap_mdev_unlink_fr_queues(struct ap_matrix_mdev *matrix_mdev)
{
	struct vfio_ap_queue *q;
	unsigned long apid, apqi;

	for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, AP_DEVICES) {
		for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm,
				     AP_DOMAINS) {
			q = vfio_ap_mdev_get_queue(matrix_mdev,
						   AP_MKQID(apid, apqi));
			if (q)
				q->matrix_mdev = NULL;
		}
	}
}

static void vfio_ap_mdev_remove(struct mdev_device *mdev)
{
	struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(&mdev->dev);

	vfio_unregister_group_dev(&matrix_mdev->vdev);

	mutex_lock(&matrix_dev->guests_lock);
	mutex_lock(&matrix_dev->mdevs_lock);
	vfio_ap_mdev_reset_queues(&matrix_mdev->qtable);
	vfio_ap_mdev_unlink_fr_queues(matrix_mdev);
	list_del(&matrix_mdev->node);
	mutex_unlock(&matrix_dev->mdevs_lock);
	mutex_unlock(&matrix_dev->guests_lock);
	vfio_uninit_group_dev(&matrix_mdev->vdev);
	kfree(matrix_mdev);
	atomic_inc(&matrix_dev->available_instances);
}

static ssize_t name_show(struct mdev_type *mtype,
			 struct mdev_type_attribute *attr, char *buf)
{
	return sprintf(buf, "%s\n", VFIO_AP_MDEV_NAME_HWVIRT);
}

static MDEV_TYPE_ATTR_RO(name);

static ssize_t available_instances_show(struct mdev_type *mtype,
					struct mdev_type_attribute *attr,
					char *buf)
{
	return sprintf(buf, "%d\n",
		       atomic_read(&matrix_dev->available_instances));
}

static MDEV_TYPE_ATTR_RO(available_instances);

static ssize_t device_api_show(struct mdev_type *mtype,
			       struct mdev_type_attribute *attr, char *buf)
{
	return sprintf(buf, "%s\n", VFIO_DEVICE_API_AP_STRING);
}

static MDEV_TYPE_ATTR_RO(device_api);

static struct attribute *vfio_ap_mdev_type_attrs[] = {
	&mdev_type_attr_name.attr,
	&mdev_type_attr_device_api.attr,
	&mdev_type_attr_available_instances.attr,
	NULL,
};

static struct attribute_group vfio_ap_mdev_hwvirt_type_group = {
	.name = VFIO_AP_MDEV_TYPE_HWVIRT,
	.attrs = vfio_ap_mdev_type_attrs,
};

static struct attribute_group *vfio_ap_mdev_type_groups[] = {
	&vfio_ap_mdev_hwvirt_type_group,
	NULL,
};

#define MDEV_SHARING_ERR "Userspace may not re-assign queue %02lx.%04lx " \
			 "already assigned to %s"

static void vfio_ap_mdev_log_sharing_err(struct ap_matrix_mdev *matrix_mdev,
					 unsigned long *apm,
					 unsigned long *aqm)
{
	unsigned long apid, apqi;
	const struct device *dev = mdev_dev(matrix_mdev->mdev);
	const char *mdev_name = dev_name(dev);

	for_each_set_bit_inv(apid, apm, AP_DEVICES)
		for_each_set_bit_inv(apqi, aqm, AP_DOMAINS)
			dev_warn(dev, MDEV_SHARING_ERR, apid, apqi, mdev_name);
}

/**
 * vfio_ap_mdev_verify_no_sharing - verify APQNs are not shared by matrix mdevs
 *
 * @mdev_apm: mask indicating the APIDs of the APQNs to be verified
 * @mdev_aqm: mask indicating the APQIs of the APQNs to be verified
 *
 * Verifies that each APQN derived from the Cartesian product of a bitmap of
 * AP adapter IDs and AP queue indexes is not configured for any matrix
 * mediated device. AP queue sharing is not allowed.
 *
 * Return: 0 if the APQNs are not shared; otherwise return -EADDRINUSE.
 */
static int vfio_ap_mdev_verify_no_sharing(unsigned long *mdev_apm,
					  unsigned long *mdev_aqm)
{
	struct ap_matrix_mdev *matrix_mdev;
	DECLARE_BITMAP(apm, AP_DEVICES);
	DECLARE_BITMAP(aqm, AP_DOMAINS);

	list_for_each_entry(matrix_mdev, &matrix_dev->mdev_list, node) {
		/*
		 * If the input apm and aqm are fields of the matrix_mdev
		 * object, then move on to the next matrix_mdev.
		 */
		if (mdev_apm == matrix_mdev->matrix.apm &&
		    mdev_aqm == matrix_mdev->matrix.aqm)
			continue;

		memset(apm, 0, sizeof(apm));
		memset(aqm, 0, sizeof(aqm));

		/*
		 * We work on full longs, as we can only exclude the leftover
		 * bits in non-inverse order. The leftover is all zeros.
		 */
		if (!bitmap_and(apm, mdev_apm, matrix_mdev->matrix.apm,
				AP_DEVICES))
			continue;

		if (!bitmap_and(aqm, mdev_aqm, matrix_mdev->matrix.aqm,
				AP_DOMAINS))
			continue;

		vfio_ap_mdev_log_sharing_err(matrix_mdev, apm, aqm);

		return -EADDRINUSE;
	}

	return 0;
}

/**
 * vfio_ap_mdev_validate_masks - verify that the APQNs assigned to the mdev are
 *				 not reserved for the default zcrypt driver and
 *				 are not assigned to another mdev.
 *
 * @matrix_mdev: the mdev to which the APQNs being validated are assigned.
 *
 * Return: One of the following values:
 * o the error returned from the ap_apqn_in_matrix_owned_by_def_drv() function,
 *   most likely -EBUSY indicating the ap_perms_mutex lock is already held.
 * o EADDRNOTAVAIL if an APQN assigned to @matrix_mdev is reserved for the
 *		   zcrypt default driver.
 * o EADDRINUSE if an APQN assigned to @matrix_mdev is assigned to another mdev
 * o A zero indicating validation succeeded.
 */
static int vfio_ap_mdev_validate_masks(struct ap_matrix_mdev *matrix_mdev)
{
	if (ap_apqn_in_matrix_owned_by_def_drv(matrix_mdev->matrix.apm,
					       matrix_mdev->matrix.aqm))
		return -EADDRNOTAVAIL;

	return vfio_ap_mdev_verify_no_sharing(matrix_mdev->matrix.apm,
					      matrix_mdev->matrix.aqm);
}

static void vfio_ap_mdev_link_adapter(struct ap_matrix_mdev *matrix_mdev,
				      unsigned long apid)
{
	unsigned long apqi;

	for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, AP_DOMAINS)
		vfio_ap_mdev_link_apqn(matrix_mdev,
				       AP_MKQID(apid, apqi));
}

/**
 * assign_adapter_store - parses the APID from @buf and sets the
 * corresponding bit in the mediated matrix device's APM
 *
 * @dev:	the matrix device
 * @attr:	the mediated matrix device's assign_adapter attribute
 * @buf:	a buffer containing the AP adapter number (APID) to
 *		be assigned
 * @count:	the number of bytes in @buf
 *
 * Return: the number of bytes processed if the APID is valid; otherwise,
 * returns one of the following errors:
 *
 *	1. -EINVAL
 *	   The APID is not a valid number
 *
 *	2. -ENODEV
 *	   The APID exceeds the maximum value configured for the system
 *
 *	3. -EADDRNOTAVAIL
 *	   An APQN derived from the cross product of the APID being assigned
 *	   and the APQIs previously assigned is not bound to the vfio_ap device
 *	   driver; or, if no APQIs have yet been assigned, the APID is not
 *	   contained in an APQN bound to the vfio_ap device driver.
 *
 *	4. -EADDRINUSE
 *	   An APQN derived from the cross product of the APID being assigned
 *	   and the APQIs previously assigned is being used by another mediated
 *	   matrix device
 *
 *	5. -EAGAIN
 *	   A lock required to validate the mdev's AP configuration could not
 *	   be obtained.
 */
static ssize_t assign_adapter_store(struct device *dev,
				    struct device_attribute *attr,
				    const char *buf, size_t count)
{
	int ret;
	unsigned long apid;
	DECLARE_BITMAP(apm_delta, AP_DEVICES);
	struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);

	mutex_lock(&ap_perms_mutex);
	get_update_locks_for_mdev(matrix_mdev);

	ret = kstrtoul(buf, 0, &apid);
	if (ret)
		goto done;

	if (apid > matrix_mdev->matrix.apm_max) {
		ret = -ENODEV;
		goto done;
	}

	set_bit_inv(apid, matrix_mdev->matrix.apm);

	ret = vfio_ap_mdev_validate_masks(matrix_mdev);
	if (ret) {
		clear_bit_inv(apid, matrix_mdev->matrix.apm);
		goto done;
	}

	vfio_ap_mdev_link_adapter(matrix_mdev, apid);
	memset(apm_delta, 0, sizeof(apm_delta));
	set_bit_inv(apid, apm_delta);

	if (vfio_ap_mdev_filter_matrix(apm_delta,
				       matrix_mdev->matrix.aqm, matrix_mdev))
		vfio_ap_mdev_update_guest_apcb(matrix_mdev);

	ret = count;
done:
	release_update_locks_for_mdev(matrix_mdev);
	mutex_unlock(&ap_perms_mutex);

	return ret;
}
static DEVICE_ATTR_WO(assign_adapter);

static struct vfio_ap_queue
*vfio_ap_unlink_apqn_fr_mdev(struct ap_matrix_mdev *matrix_mdev,
			     unsigned long apid, unsigned long apqi)
{
	struct vfio_ap_queue *q = NULL;

	q = vfio_ap_mdev_get_queue(matrix_mdev, AP_MKQID(apid, apqi));
	/* If the queue is assigned to the matrix mdev, unlink it. */
	if (q)
		vfio_ap_unlink_queue_fr_mdev(q);

	return q;
}

/**
 * vfio_ap_mdev_unlink_adapter - unlink all queues associated with unassigned
 *				 adapter from the matrix mdev to which the
 *				 adapter was assigned.
 * @matrix_mdev: the matrix mediated device to which the adapter was assigned.
 * @apid: the APID of the unassigned adapter.
 * @qtable: table for storing queues associated with unassigned adapter.
 */
static void vfio_ap_mdev_unlink_adapter(struct ap_matrix_mdev *matrix_mdev,
					unsigned long apid,
					struct ap_queue_table *qtable)
{
	unsigned long apqi;
	struct vfio_ap_queue *q;

	for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, AP_DOMAINS) {
		q = vfio_ap_unlink_apqn_fr_mdev(matrix_mdev, apid, apqi);

		if (q && qtable) {
			if (test_bit_inv(apid, matrix_mdev->shadow_apcb.apm) &&
			    test_bit_inv(apqi, matrix_mdev->shadow_apcb.aqm))
				hash_add(qtable->queues, &q->mdev_qnode,
					 q->apqn);
		}
	}
}

static void vfio_ap_mdev_hot_unplug_adapter(struct ap_matrix_mdev *matrix_mdev,
					    unsigned long apid)
{
	int loop_cursor;
	struct vfio_ap_queue *q;
	struct ap_queue_table *qtable = kzalloc(sizeof(*qtable), GFP_KERNEL);

	hash_init(qtable->queues);
	vfio_ap_mdev_unlink_adapter(matrix_mdev, apid, qtable);

	if (test_bit_inv(apid, matrix_mdev->shadow_apcb.apm)) {
		clear_bit_inv(apid, matrix_mdev->shadow_apcb.apm);
		vfio_ap_mdev_update_guest_apcb(matrix_mdev);
	}

	vfio_ap_mdev_reset_queues(qtable);

	hash_for_each(qtable->queues, loop_cursor, q, mdev_qnode) {
		vfio_ap_unlink_mdev_fr_queue(q);
		hash_del(&q->mdev_qnode);
	}

	kfree(qtable);
}

/**
 * unassign_adapter_store - parses the APID from @buf and clears the
 * corresponding bit in the mediated matrix device's APM
 *
 * @dev:	the matrix device
 * @attr:	the mediated matrix device's unassign_adapter attribute
 * @buf:	a buffer containing the adapter number (APID) to be unassigned
 * @count:	the number of bytes in @buf
 *
 * Return: the number of bytes processed if the APID is valid; otherwise,
 * returns one of the following errors:
 *	-EINVAL if the APID is not a number
 *	-ENODEV if the APID it exceeds the maximum value configured for the
 *		system
 */
static ssize_t unassign_adapter_store(struct device *dev,
				      struct device_attribute *attr,
				      const char *buf, size_t count)
{
	int ret;
	unsigned long apid;
	struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);

	get_update_locks_for_mdev(matrix_mdev);

	ret = kstrtoul(buf, 0, &apid);
	if (ret)
		goto done;

	if (apid > matrix_mdev->matrix.apm_max) {
		ret = -ENODEV;
		goto done;
	}

	clear_bit_inv((unsigned long)apid, matrix_mdev->matrix.apm);
	vfio_ap_mdev_hot_unplug_adapter(matrix_mdev, apid);
	ret = count;
done:
	release_update_locks_for_mdev(matrix_mdev);
	return ret;
}
static DEVICE_ATTR_WO(unassign_adapter);

static void vfio_ap_mdev_link_domain(struct ap_matrix_mdev *matrix_mdev,
				     unsigned long apqi)
{
	unsigned long apid;

	for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, AP_DEVICES)
		vfio_ap_mdev_link_apqn(matrix_mdev,
				       AP_MKQID(apid, apqi));
}

/**
 * assign_domain_store - parses the APQI from @buf and sets the
 * corresponding bit in the mediated matrix device's AQM
 *
 * @dev:	the matrix device
 * @attr:	the mediated matrix device's assign_domain attribute
 * @buf:	a buffer containing the AP queue index (APQI) of the domain to
 *		be assigned
 * @count:	the number of bytes in @buf
 *
 * Return: the number of bytes processed if the APQI is valid; otherwise returns
 * one of the following errors:
 *
 *	1. -EINVAL
 *	   The APQI is not a valid number
 *
 *	2. -ENODEV
 *	   The APQI exceeds the maximum value configured for the system
 *
 *	3. -EADDRNOTAVAIL
 *	   An APQN derived from the cross product of the APQI being assigned
 *	   and the APIDs previously assigned is not bound to the vfio_ap device
 *	   driver; or, if no APIDs have yet been assigned, the APQI is not
 *	   contained in an APQN bound to the vfio_ap device driver.
 *
 *	4. -EADDRINUSE
 *	   An APQN derived from the cross product of the APQI being assigned
 *	   and the APIDs previously assigned is being used by another mediated
 *	   matrix device
 *
 *	5. -EAGAIN
 *	   The lock required to validate the mdev's AP configuration could not
 *	   be obtained.
 */
static ssize_t assign_domain_store(struct device *dev,
				   struct device_attribute *attr,
				   const char *buf, size_t count)
{
	int ret;
	unsigned long apqi;
	DECLARE_BITMAP(aqm_delta, AP_DOMAINS);
	struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);

	mutex_lock(&ap_perms_mutex);
	get_update_locks_for_mdev(matrix_mdev);

	ret = kstrtoul(buf, 0, &apqi);
	if (ret)
		goto done;

	if (apqi > matrix_mdev->matrix.aqm_max) {
		ret = -ENODEV;
		goto done;
	}

	set_bit_inv(apqi, matrix_mdev->matrix.aqm);

	ret = vfio_ap_mdev_validate_masks(matrix_mdev);
	if (ret) {
		clear_bit_inv(apqi, matrix_mdev->matrix.aqm);
		goto done;
	}

	vfio_ap_mdev_link_domain(matrix_mdev, apqi);
	memset(aqm_delta, 0, sizeof(aqm_delta));
	set_bit_inv(apqi, aqm_delta);

	if (vfio_ap_mdev_filter_matrix(matrix_mdev->matrix.apm, aqm_delta,
				       matrix_mdev))
		vfio_ap_mdev_update_guest_apcb(matrix_mdev);

	ret = count;
done:
	release_update_locks_for_mdev(matrix_mdev);
	mutex_unlock(&ap_perms_mutex);

	return ret;
}
static DEVICE_ATTR_WO(assign_domain);

static void vfio_ap_mdev_unlink_domain(struct ap_matrix_mdev *matrix_mdev,
				       unsigned long apqi,
				       struct ap_queue_table *qtable)
{
	unsigned long apid;
	struct vfio_ap_queue *q;

	for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, AP_DEVICES) {
		q = vfio_ap_unlink_apqn_fr_mdev(matrix_mdev, apid, apqi);

		if (q && qtable) {
			if (test_bit_inv(apid, matrix_mdev->shadow_apcb.apm) &&
			    test_bit_inv(apqi, matrix_mdev->shadow_apcb.aqm))
				hash_add(qtable->queues, &q->mdev_qnode,
					 q->apqn);
		}
	}
}

static void vfio_ap_mdev_hot_unplug_domain(struct ap_matrix_mdev *matrix_mdev,
					   unsigned long apqi)
{
	int loop_cursor;
	struct vfio_ap_queue *q;
	struct ap_queue_table *qtable = kzalloc(sizeof(*qtable), GFP_KERNEL);

	hash_init(qtable->queues);
	vfio_ap_mdev_unlink_domain(matrix_mdev, apqi, qtable);

	if (test_bit_inv(apqi, matrix_mdev->shadow_apcb.aqm)) {
		clear_bit_inv(apqi, matrix_mdev->shadow_apcb.aqm);
		vfio_ap_mdev_update_guest_apcb(matrix_mdev);
	}

	vfio_ap_mdev_reset_queues(qtable);

	hash_for_each(qtable->queues, loop_cursor, q, mdev_qnode) {
		vfio_ap_unlink_mdev_fr_queue(q);
		hash_del(&q->mdev_qnode);
	}

	kfree(qtable);
}

/**
 * unassign_domain_store - parses the APQI from @buf and clears the
 * corresponding bit in the mediated matrix device's AQM
 *
 * @dev:	the matrix device
 * @attr:	the mediated matrix device's unassign_domain attribute
 * @buf:	a buffer containing the AP queue index (APQI) of the domain to
 *		be unassigned
 * @count:	the number of bytes in @buf
 *
 * Return: the number of bytes processed if the APQI is valid; otherwise,
 * returns one of the following errors:
 *	-EINVAL if the APQI is not a number
 *	-ENODEV if the APQI exceeds the maximum value configured for the system
 */
static ssize_t unassign_domain_store(struct device *dev,
				     struct device_attribute *attr,
				     const char *buf, size_t count)
{
	int ret;
	unsigned long apqi;
	struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);

	get_update_locks_for_mdev(matrix_mdev);

	ret = kstrtoul(buf, 0, &apqi);
	if (ret)
		goto done;

	if (apqi > matrix_mdev->matrix.aqm_max) {
		ret = -ENODEV;
		goto done;
	}

	clear_bit_inv((unsigned long)apqi, matrix_mdev->matrix.aqm);
	vfio_ap_mdev_hot_unplug_domain(matrix_mdev, apqi);
	ret = count;

done:
	release_update_locks_for_mdev(matrix_mdev);
	return ret;
}
static DEVICE_ATTR_WO(unassign_domain);

/**
 * assign_control_domain_store - parses the domain ID from @buf and sets
 * the corresponding bit in the mediated matrix device's ADM
 *
 * @dev:	the matrix device
 * @attr:	the mediated matrix device's assign_control_domain attribute
 * @buf:	a buffer containing the domain ID to be assigned
 * @count:	the number of bytes in @buf
 *
 * Return: the number of bytes processed if the domain ID is valid; otherwise,
 * returns one of the following errors:
 *	-EINVAL if the ID is not a number
 *	-ENODEV if the ID exceeds the maximum value configured for the system
 */
static ssize_t assign_control_domain_store(struct device *dev,
					   struct device_attribute *attr,
					   const char *buf, size_t count)
{
	int ret;
	unsigned long id;
	struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);

	get_update_locks_for_mdev(matrix_mdev);

	ret = kstrtoul(buf, 0, &id);
	if (ret)
		goto done;

	if (id > matrix_mdev->matrix.adm_max) {
		ret = -ENODEV;
		goto done;
	}

	/* Set the bit in the ADM (bitmask) corresponding to the AP control
	 * domain number (id). The bits in the mask, from most significant to
	 * least significant, correspond to IDs 0 up to the one less than the
	 * number of control domains that can be assigned.
	 */
	set_bit_inv(id, matrix_mdev->matrix.adm);
	if (vfio_ap_mdev_filter_cdoms(matrix_mdev))
		vfio_ap_mdev_update_guest_apcb(matrix_mdev);

	ret = count;
done:
	release_update_locks_for_mdev(matrix_mdev);
	return ret;
}
static DEVICE_ATTR_WO(assign_control_domain);

/**
 * unassign_control_domain_store - parses the domain ID from @buf and
 * clears the corresponding bit in the mediated matrix device's ADM
 *
 * @dev:	the matrix device
 * @attr:	the mediated matrix device's unassign_control_domain attribute
 * @buf:	a buffer containing the domain ID to be unassigned
 * @count:	the number of bytes in @buf
 *
 * Return: the number of bytes processed if the domain ID is valid; otherwise,
 * returns one of the following errors:
 *	-EINVAL if the ID is not a number
 *	-ENODEV if the ID exceeds the maximum value configured for the system
 */
static ssize_t unassign_control_domain_store(struct device *dev,
					     struct device_attribute *attr,
					     const char *buf, size_t count)
{
	int ret;
	unsigned long domid;
	struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);

	get_update_locks_for_mdev(matrix_mdev);

	ret = kstrtoul(buf, 0, &domid);
	if (ret)
		goto done;

	if (domid > matrix_mdev->matrix.adm_max) {
		ret = -ENODEV;
		goto done;
	}

	clear_bit_inv(domid, matrix_mdev->matrix.adm);

	if (test_bit_inv(domid, matrix_mdev->shadow_apcb.adm)) {
		clear_bit_inv(domid, matrix_mdev->shadow_apcb.adm);
		vfio_ap_mdev_update_guest_apcb(matrix_mdev);
	}

	ret = count;
done:
	release_update_locks_for_mdev(matrix_mdev);
	return ret;
}
static DEVICE_ATTR_WO(unassign_control_domain);

static ssize_t control_domains_show(struct device *dev,
				    struct device_attribute *dev_attr,
				    char *buf)
{
	unsigned long id;
	int nchars = 0;
	int n;
	char *bufpos = buf;
	struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);
	unsigned long max_domid = matrix_mdev->matrix.adm_max;

	mutex_lock(&matrix_dev->mdevs_lock);
	for_each_set_bit_inv(id, matrix_mdev->matrix.adm, max_domid + 1) {
		n = sprintf(bufpos, "%04lx\n", id);
		bufpos += n;
		nchars += n;
	}
	mutex_unlock(&matrix_dev->mdevs_lock);

	return nchars;
}
static DEVICE_ATTR_RO(control_domains);

static ssize_t vfio_ap_mdev_matrix_show(struct ap_matrix *matrix, char *buf)
{
	char *bufpos = buf;
	unsigned long apid;
	unsigned long apqi;
	unsigned long apid1;
	unsigned long apqi1;
	unsigned long napm_bits = matrix->apm_max + 1;
	unsigned long naqm_bits = matrix->aqm_max + 1;
	int nchars = 0;
	int n;

	apid1 = find_first_bit_inv(matrix->apm, napm_bits);
	apqi1 = find_first_bit_inv(matrix->aqm, naqm_bits);

	if ((apid1 < napm_bits) && (apqi1 < naqm_bits)) {
		for_each_set_bit_inv(apid, matrix->apm, napm_bits) {
			for_each_set_bit_inv(apqi, matrix->aqm,
					     naqm_bits) {
				n = sprintf(bufpos, "%02lx.%04lx\n", apid,
					    apqi);
				bufpos += n;
				nchars += n;
			}
		}
	} else if (apid1 < napm_bits) {
		for_each_set_bit_inv(apid, matrix->apm, napm_bits) {
			n = sprintf(bufpos, "%02lx.\n", apid);
			bufpos += n;
			nchars += n;
		}
	} else if (apqi1 < naqm_bits) {
		for_each_set_bit_inv(apqi, matrix->aqm, naqm_bits) {
			n = sprintf(bufpos, ".%04lx\n", apqi);
			bufpos += n;
			nchars += n;
		}
	}

	return nchars;
}

static ssize_t matrix_show(struct device *dev, struct device_attribute *attr,
			   char *buf)
{
	ssize_t nchars;
	struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);

	mutex_lock(&matrix_dev->mdevs_lock);
	nchars = vfio_ap_mdev_matrix_show(&matrix_mdev->matrix, buf);
	mutex_unlock(&matrix_dev->mdevs_lock);

	return nchars;
}
static DEVICE_ATTR_RO(matrix);

static ssize_t guest_matrix_show(struct device *dev,
				 struct device_attribute *attr, char *buf)
{
	ssize_t nchars;
	struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);

	mutex_lock(&matrix_dev->mdevs_lock);
	nchars = vfio_ap_mdev_matrix_show(&matrix_mdev->shadow_apcb, buf);
	mutex_unlock(&matrix_dev->mdevs_lock);

	return nchars;
}
static DEVICE_ATTR_RO(guest_matrix);

static struct attribute *vfio_ap_mdev_attrs[] = {
	&dev_attr_assign_adapter.attr,
	&dev_attr_unassign_adapter.attr,
	&dev_attr_assign_domain.attr,
	&dev_attr_unassign_domain.attr,
	&dev_attr_assign_control_domain.attr,
	&dev_attr_unassign_control_domain.attr,
	&dev_attr_control_domains.attr,
	&dev_attr_matrix.attr,
	&dev_attr_guest_matrix.attr,
	NULL,
};

static struct attribute_group vfio_ap_mdev_attr_group = {
	.attrs = vfio_ap_mdev_attrs
};

static const struct attribute_group *vfio_ap_mdev_attr_groups[] = {
	&vfio_ap_mdev_attr_group,
	NULL
};

/**
 * vfio_ap_mdev_set_kvm - sets all data for @matrix_mdev that are needed
 * to manage AP resources for the guest whose state is represented by @kvm
 *
 * @matrix_mdev: a mediated matrix device
 * @kvm: reference to KVM instance
 *
 * Return: 0 if no other mediated matrix device has a reference to @kvm;
 * otherwise, returns an -EPERM.
 */
static int vfio_ap_mdev_set_kvm(struct ap_matrix_mdev *matrix_mdev,
				struct kvm *kvm)
{
	struct ap_matrix_mdev *m;

	if (kvm->arch.crypto.crycbd) {
		down_write(&kvm->arch.crypto.pqap_hook_rwsem);
		kvm->arch.crypto.pqap_hook = &matrix_mdev->pqap_hook;
		up_write(&kvm->arch.crypto.pqap_hook_rwsem);

		get_update_locks_for_kvm(kvm);

		list_for_each_entry(m, &matrix_dev->mdev_list, node) {
			if (m != matrix_mdev && m->kvm == kvm) {
				release_update_locks_for_kvm(kvm);
				return -EPERM;
			}
		}

		kvm_get_kvm(kvm);
		matrix_mdev->kvm = kvm;
		vfio_ap_mdev_update_guest_apcb(matrix_mdev);

		release_update_locks_for_kvm(kvm);
	}

	return 0;
}

static void vfio_ap_mdev_dma_unmap(struct vfio_device *vdev, u64 iova,
				   u64 length)
{
	struct ap_matrix_mdev *matrix_mdev =
		container_of(vdev, struct ap_matrix_mdev, vdev);

	vfio_unpin_pages(&matrix_mdev->vdev, iova, 1);
}

/**
 * vfio_ap_mdev_unset_kvm - performs clean-up of resources no longer needed
 * by @matrix_mdev.
 *
 * @matrix_mdev: a matrix mediated device
 */
static void vfio_ap_mdev_unset_kvm(struct ap_matrix_mdev *matrix_mdev)
{
	struct kvm *kvm = matrix_mdev->kvm;

	if (kvm && kvm->arch.crypto.crycbd) {
		down_write(&kvm->arch.crypto.pqap_hook_rwsem);
		kvm->arch.crypto.pqap_hook = NULL;
		up_write(&kvm->arch.crypto.pqap_hook_rwsem);

		get_update_locks_for_kvm(kvm);

		kvm_arch_crypto_clear_masks(kvm);
		vfio_ap_mdev_reset_queues(&matrix_mdev->qtable);
		kvm_put_kvm(kvm);
		matrix_mdev->kvm = NULL;

		release_update_locks_for_kvm(kvm);
	}
}

static struct vfio_ap_queue *vfio_ap_find_queue(int apqn)
{
	struct ap_queue *queue;
	struct vfio_ap_queue *q = NULL;

	queue = ap_get_qdev(apqn);
	if (!queue)
		return NULL;

	if (queue->ap_dev.device.driver == &matrix_dev->vfio_ap_drv->driver)
		q = dev_get_drvdata(&queue->ap_dev.device);

	put_device(&queue->ap_dev.device);

	return q;
}

static int vfio_ap_mdev_reset_queue(struct vfio_ap_queue *q,
				    unsigned int retry)
{
	struct ap_queue_status status;
	int ret;
	int retry2 = 2;

	if (!q)
		return 0;
retry_zapq:
	status = ap_zapq(q->apqn);
	q->reset_rc = status.response_code;
	switch (status.response_code) {
	case AP_RESPONSE_NORMAL:
		ret = 0;
		break;
	case AP_RESPONSE_RESET_IN_PROGRESS:
		if (retry--) {
			msleep(20);
			goto retry_zapq;
		}
		ret = -EBUSY;
		break;
	case AP_RESPONSE_Q_NOT_AVAIL:
	case AP_RESPONSE_DECONFIGURED:
	case AP_RESPONSE_CHECKSTOPPED:
		WARN_ONCE(status.irq_enabled,
			  "PQAP/ZAPQ for %02x.%04x failed with rc=%u while IRQ enabled",
			  AP_QID_CARD(q->apqn), AP_QID_QUEUE(q->apqn),
			  status.response_code);
		ret = -EBUSY;
		goto free_resources;
	default:
		/* things are really broken, give up */
		WARN(true,
		     "PQAP/ZAPQ for %02x.%04x failed with invalid rc=%u\n",
		     AP_QID_CARD(q->apqn), AP_QID_QUEUE(q->apqn),
		     status.response_code);
		return -EIO;
	}

	/* wait for the reset to take effect */
	while (retry2--) {
		if (status.queue_empty && !status.irq_enabled)
			break;
		msleep(20);
		status = ap_tapq(q->apqn, NULL);
	}
	WARN_ONCE(retry2 <= 0, "unable to verify reset of queue %02x.%04x",
		  AP_QID_CARD(q->apqn), AP_QID_QUEUE(q->apqn));

free_resources:
	vfio_ap_free_aqic_resources(q);

	return ret;
}

static int vfio_ap_mdev_reset_queues(struct ap_queue_table *qtable)
{
	int ret, loop_cursor, rc = 0;
	struct vfio_ap_queue *q;

	hash_for_each(qtable->queues, loop_cursor, q, mdev_qnode) {
		ret = vfio_ap_mdev_reset_queue(q, 1);
		/*
		 * Regardless whether a queue turns out to be busy, or
		 * is not operational, we need to continue resetting
		 * the remaining queues.
		 */
		if (ret)
			rc = ret;
	}

	return rc;
}

static int vfio_ap_mdev_open_device(struct vfio_device *vdev)
{
	struct ap_matrix_mdev *matrix_mdev =
		container_of(vdev, struct ap_matrix_mdev, vdev);

	if (!vdev->kvm)
		return -EINVAL;

	return vfio_ap_mdev_set_kvm(matrix_mdev, vdev->kvm);
}

static void vfio_ap_mdev_close_device(struct vfio_device *vdev)
{
	struct ap_matrix_mdev *matrix_mdev =
		container_of(vdev, struct ap_matrix_mdev, vdev);

	vfio_ap_mdev_unset_kvm(matrix_mdev);
}

static int vfio_ap_mdev_get_device_info(unsigned long arg)
{
	unsigned long minsz;
	struct vfio_device_info info;

	minsz = offsetofend(struct vfio_device_info, num_irqs);

	if (copy_from_user(&info, (void __user *)arg, minsz))
		return -EFAULT;

	if (info.argsz < minsz)
		return -EINVAL;

	info.flags = VFIO_DEVICE_FLAGS_AP | VFIO_DEVICE_FLAGS_RESET;
	info.num_regions = 0;
	info.num_irqs = 0;

	return copy_to_user((void __user *)arg, &info, minsz) ? -EFAULT : 0;
}

static ssize_t vfio_ap_mdev_ioctl(struct vfio_device *vdev,
				    unsigned int cmd, unsigned long arg)
{
	struct ap_matrix_mdev *matrix_mdev =
		container_of(vdev, struct ap_matrix_mdev, vdev);
	int ret;

	mutex_lock(&matrix_dev->mdevs_lock);
	switch (cmd) {
	case VFIO_DEVICE_GET_INFO:
		ret = vfio_ap_mdev_get_device_info(arg);
		break;
	case VFIO_DEVICE_RESET:
		ret = vfio_ap_mdev_reset_queues(&matrix_mdev->qtable);
		break;
	default:
		ret = -EOPNOTSUPP;
		break;
	}
	mutex_unlock(&matrix_dev->mdevs_lock);

	return ret;
}

static struct ap_matrix_mdev *vfio_ap_mdev_for_queue(struct vfio_ap_queue *q)
{
	struct ap_matrix_mdev *matrix_mdev;
	unsigned long apid = AP_QID_CARD(q->apqn);
	unsigned long apqi = AP_QID_QUEUE(q->apqn);

	list_for_each_entry(matrix_mdev, &matrix_dev->mdev_list, node) {
		if (test_bit_inv(apid, matrix_mdev->matrix.apm) &&
		    test_bit_inv(apqi, matrix_mdev->matrix.aqm))
			return matrix_mdev;
	}

	return NULL;
}

static ssize_t status_show(struct device *dev,
			   struct device_attribute *attr,
			   char *buf)
{
	ssize_t nchars = 0;
	struct vfio_ap_queue *q;
	struct ap_matrix_mdev *matrix_mdev;
	struct ap_device *apdev = to_ap_dev(dev);

	mutex_lock(&matrix_dev->mdevs_lock);
	q = dev_get_drvdata(&apdev->device);
	matrix_mdev = vfio_ap_mdev_for_queue(q);

	if (matrix_mdev) {
		if (matrix_mdev->kvm)
			nchars = scnprintf(buf, PAGE_SIZE, "%s\n",
					   AP_QUEUE_IN_USE);
		else
			nchars = scnprintf(buf, PAGE_SIZE, "%s\n",
					   AP_QUEUE_ASSIGNED);
	} else {
		nchars = scnprintf(buf, PAGE_SIZE, "%s\n",
				   AP_QUEUE_UNASSIGNED);
	}

	mutex_unlock(&matrix_dev->mdevs_lock);

	return nchars;
}

static DEVICE_ATTR_RO(status);

static struct attribute *vfio_queue_attrs[] = {
	&dev_attr_status.attr,
	NULL,
};

static const struct attribute_group vfio_queue_attr_group = {
	.attrs = vfio_queue_attrs,
};

static const struct vfio_device_ops vfio_ap_matrix_dev_ops = {
	.open_device = vfio_ap_mdev_open_device,
	.close_device = vfio_ap_mdev_close_device,
	.ioctl = vfio_ap_mdev_ioctl,
	.dma_unmap = vfio_ap_mdev_dma_unmap,
};

static struct mdev_driver vfio_ap_matrix_driver = {
	.driver = {
		.name = "vfio_ap_mdev",
		.owner = THIS_MODULE,
		.mod_name = KBUILD_MODNAME,
		.dev_groups = vfio_ap_mdev_attr_groups,
	},
	.probe = vfio_ap_mdev_probe,
	.remove = vfio_ap_mdev_remove,
	.supported_type_groups = vfio_ap_mdev_type_groups,
};

int vfio_ap_mdev_register(void)
{
	int ret;

	atomic_set(&matrix_dev->available_instances, MAX_ZDEV_ENTRIES_EXT);

	ret = mdev_register_driver(&vfio_ap_matrix_driver);
	if (ret)
		return ret;

	ret = mdev_register_device(&matrix_dev->device, &vfio_ap_matrix_driver);
	if (ret)
		goto err_driver;
	return 0;

err_driver:
	mdev_unregister_driver(&vfio_ap_matrix_driver);
	return ret;
}

void vfio_ap_mdev_unregister(void)
{
	mdev_unregister_device(&matrix_dev->device);
	mdev_unregister_driver(&vfio_ap_matrix_driver);
}

int vfio_ap_mdev_probe_queue(struct ap_device *apdev)
{
	int ret;
	struct vfio_ap_queue *q;
	struct ap_matrix_mdev *matrix_mdev;

	ret = sysfs_create_group(&apdev->device.kobj, &vfio_queue_attr_group);
	if (ret)
		return ret;

	q = kzalloc(sizeof(*q), GFP_KERNEL);
	if (!q)
		return -ENOMEM;

	q->apqn = to_ap_queue(&apdev->device)->qid;
	q->saved_isc = VFIO_AP_ISC_INVALID;
	matrix_mdev = get_update_locks_by_apqn(q->apqn);

	if (matrix_mdev) {
		vfio_ap_mdev_link_queue(matrix_mdev, q);

		if (vfio_ap_mdev_filter_matrix(matrix_mdev->matrix.apm,
					       matrix_mdev->matrix.aqm,
					       matrix_mdev))
			vfio_ap_mdev_update_guest_apcb(matrix_mdev);
	}
	dev_set_drvdata(&apdev->device, q);
	release_update_locks_for_mdev(matrix_mdev);

	return 0;
}

void vfio_ap_mdev_remove_queue(struct ap_device *apdev)
{
	unsigned long apid, apqi;
	struct vfio_ap_queue *q;
	struct ap_matrix_mdev *matrix_mdev;

	sysfs_remove_group(&apdev->device.kobj, &vfio_queue_attr_group);
	q = dev_get_drvdata(&apdev->device);
	get_update_locks_for_queue(q);
	matrix_mdev = q->matrix_mdev;

	if (matrix_mdev) {
		vfio_ap_unlink_queue_fr_mdev(q);

		apid = AP_QID_CARD(q->apqn);
		apqi = AP_QID_QUEUE(q->apqn);

		/*
		 * If the queue is assigned to the guest's APCB, then remove
		 * the adapter's APID from the APCB and hot it into the guest.
		 */
		if (test_bit_inv(apid, matrix_mdev->shadow_apcb.apm) &&
		    test_bit_inv(apqi, matrix_mdev->shadow_apcb.aqm)) {
			clear_bit_inv(apid, matrix_mdev->shadow_apcb.apm);
			vfio_ap_mdev_update_guest_apcb(matrix_mdev);
		}
	}

	vfio_ap_mdev_reset_queue(q, 1);
	dev_set_drvdata(&apdev->device, NULL);
	kfree(q);
	release_update_locks_for_mdev(matrix_mdev);
}

/**
 * vfio_ap_mdev_resource_in_use: check whether any of a set of APQNs is
 *				 assigned to a mediated device under the control
 *				 of the vfio_ap device driver.
 *
 * @apm: a bitmap specifying a set of APIDs comprising the APQNs to check.
 * @aqm: a bitmap specifying a set of APQIs comprising the APQNs to check.
 *
 * Return:
 *	* -EADDRINUSE if one or more of the APQNs specified via @apm/@aqm are
 *	  assigned to a mediated device under the control of the vfio_ap
 *	  device driver.
 *	* Otherwise, return 0.
 */
int vfio_ap_mdev_resource_in_use(unsigned long *apm, unsigned long *aqm)
{
	int ret;

	mutex_lock(&matrix_dev->guests_lock);
	mutex_lock(&matrix_dev->mdevs_lock);
	ret = vfio_ap_mdev_verify_no_sharing(apm, aqm);
	mutex_unlock(&matrix_dev->mdevs_lock);
	mutex_unlock(&matrix_dev->guests_lock);

	return ret;
}

/**
 * vfio_ap_mdev_hot_unplug_cfg - hot unplug the adapters, domains and control
 *				 domains that have been removed from the host's
 *				 AP configuration from a guest.
 *
 * @matrix_mdev: an ap_matrix_mdev object attached to a KVM guest.
 * @aprem: the adapters that have been removed from the host's AP configuration
 * @aqrem: the domains that have been removed from the host's AP configuration
 * @cdrem: the control domains that have been removed from the host's AP
 *	   configuration.
 */
static void vfio_ap_mdev_hot_unplug_cfg(struct ap_matrix_mdev *matrix_mdev,
					unsigned long *aprem,
					unsigned long *aqrem,
					unsigned long *cdrem)
{
	int do_hotplug = 0;

	if (!bitmap_empty(aprem, AP_DEVICES)) {
		do_hotplug |= bitmap_andnot(matrix_mdev->shadow_apcb.apm,
					    matrix_mdev->shadow_apcb.apm,
					    aprem, AP_DEVICES);
	}

	if (!bitmap_empty(aqrem, AP_DOMAINS)) {
		do_hotplug |= bitmap_andnot(matrix_mdev->shadow_apcb.aqm,
					    matrix_mdev->shadow_apcb.aqm,
					    aqrem, AP_DEVICES);
	}

	if (!bitmap_empty(cdrem, AP_DOMAINS))
		do_hotplug |= bitmap_andnot(matrix_mdev->shadow_apcb.adm,
					    matrix_mdev->shadow_apcb.adm,
					    cdrem, AP_DOMAINS);

	if (do_hotplug)
		vfio_ap_mdev_update_guest_apcb(matrix_mdev);
}

/**
 * vfio_ap_mdev_cfg_remove - determines which guests are using the adapters,
 *			     domains and control domains that have been removed
 *			     from the host AP configuration and unplugs them
 *			     from those guests.
 *
 * @ap_remove:	bitmap specifying which adapters have been removed from the host
 *		config.
 * @aq_remove:	bitmap specifying which domains have been removed from the host
 *		config.
 * @cd_remove:	bitmap specifying which control domains have been removed from
 *		the host config.
 */
static void vfio_ap_mdev_cfg_remove(unsigned long *ap_remove,
				    unsigned long *aq_remove,
				    unsigned long *cd_remove)
{
	struct ap_matrix_mdev *matrix_mdev;
	DECLARE_BITMAP(aprem, AP_DEVICES);
	DECLARE_BITMAP(aqrem, AP_DOMAINS);
	DECLARE_BITMAP(cdrem, AP_DOMAINS);
	int do_remove = 0;

	list_for_each_entry(matrix_mdev, &matrix_dev->mdev_list, node) {
		mutex_lock(&matrix_mdev->kvm->lock);
		mutex_lock(&matrix_dev->mdevs_lock);

		do_remove |= bitmap_and(aprem, ap_remove,
					  matrix_mdev->matrix.apm,
					  AP_DEVICES);
		do_remove |= bitmap_and(aqrem, aq_remove,
					  matrix_mdev->matrix.aqm,
					  AP_DOMAINS);
		do_remove |= bitmap_andnot(cdrem, cd_remove,
					     matrix_mdev->matrix.adm,
					     AP_DOMAINS);

		if (do_remove)
			vfio_ap_mdev_hot_unplug_cfg(matrix_mdev, aprem, aqrem,
						    cdrem);

		mutex_unlock(&matrix_dev->mdevs_lock);
		mutex_unlock(&matrix_mdev->kvm->lock);
	}
}

/**
 * vfio_ap_mdev_on_cfg_remove - responds to the removal of adapters, domains and
 *				control domains from the host AP configuration
 *				by unplugging them from the guests that are
 *				using them.
 * @cur_config_info: the current host AP configuration information
 * @prev_config_info: the previous host AP configuration information
 */
static void vfio_ap_mdev_on_cfg_remove(struct ap_config_info *cur_config_info,
				       struct ap_config_info *prev_config_info)
{
	int do_remove;
	DECLARE_BITMAP(aprem, AP_DEVICES);
	DECLARE_BITMAP(aqrem, AP_DOMAINS);
	DECLARE_BITMAP(cdrem, AP_DOMAINS);

	do_remove = bitmap_andnot(aprem,
				  (unsigned long *)prev_config_info->apm,
				  (unsigned long *)cur_config_info->apm,
				  AP_DEVICES);
	do_remove |= bitmap_andnot(aqrem,
				   (unsigned long *)prev_config_info->aqm,
				   (unsigned long *)cur_config_info->aqm,
				   AP_DEVICES);
	do_remove |= bitmap_andnot(cdrem,
				   (unsigned long *)prev_config_info->adm,
				   (unsigned long *)cur_config_info->adm,
				   AP_DEVICES);

	if (do_remove)
		vfio_ap_mdev_cfg_remove(aprem, aqrem, cdrem);
}

/**
 * vfio_ap_filter_apid_by_qtype: filter APIDs from an AP mask for adapters that
 *				 are older than AP type 10 (CEX4).
 * @apm: a bitmap of the APIDs to examine
 * @aqm: a bitmap of the APQIs of the queues to query for the AP type.
 */
static void vfio_ap_filter_apid_by_qtype(unsigned long *apm, unsigned long *aqm)
{
	bool apid_cleared;
	struct ap_queue_status status;
	unsigned long apid, apqi, info;
	int qtype, qtype_mask = 0xff000000;

	for_each_set_bit_inv(apid, apm, AP_DEVICES) {
		apid_cleared = false;

		for_each_set_bit_inv(apqi, aqm, AP_DOMAINS) {
			status = ap_test_queue(AP_MKQID(apid, apqi), 1, &info);
			switch (status.response_code) {
			/*
			 * According to the architecture in each case
			 * below, the queue's info should be filled.
			 */
			case AP_RESPONSE_NORMAL:
			case AP_RESPONSE_RESET_IN_PROGRESS:
			case AP_RESPONSE_DECONFIGURED:
			case AP_RESPONSE_CHECKSTOPPED:
			case AP_RESPONSE_BUSY:
				qtype = info & qtype_mask;

				/*
				 * The vfio_ap device driver only
				 * supports CEX4 and newer adapters, so
				 * remove the APID if the adapter is
				 * older than a CEX4.
				 */
				if (qtype < AP_DEVICE_TYPE_CEX4) {
					clear_bit_inv(apid, apm);
					apid_cleared = true;
				}

				break;

			default:
				/*
				 * If we don't know the adapter type,
				 * clear its APID since it can't be
				 * determined whether the vfio_ap
				 * device driver supports it.
				 */
				clear_bit_inv(apid, apm);
				apid_cleared = true;
				break;
			}

			/*
			 * If we've already cleared the APID from the apm, there
			 * is no need to continue examining the remainin AP
			 * queues to determine the type of the adapter.
			 */
			if (apid_cleared)
				continue;
		}
	}
}

/**
 * vfio_ap_mdev_cfg_add - store bitmaps specifying the adapters, domains and
 *			  control domains that have been added to the host's
 *			  AP configuration for each matrix mdev to which they
 *			  are assigned.
 *
 * @apm_add: a bitmap specifying the adapters that have been added to the AP
 *	     configuration.
 * @aqm_add: a bitmap specifying the domains that have been added to the AP
 *	     configuration.
 * @adm_add: a bitmap specifying the control domains that have been added to the
 *	     AP configuration.
 */
static void vfio_ap_mdev_cfg_add(unsigned long *apm_add, unsigned long *aqm_add,
				 unsigned long *adm_add)
{
	struct ap_matrix_mdev *matrix_mdev;

	if (list_empty(&matrix_dev->mdev_list))
		return;

	vfio_ap_filter_apid_by_qtype(apm_add, aqm_add);

	list_for_each_entry(matrix_mdev, &matrix_dev->mdev_list, node) {
		bitmap_and(matrix_mdev->apm_add,
			   matrix_mdev->matrix.apm, apm_add, AP_DEVICES);
		bitmap_and(matrix_mdev->aqm_add,
			   matrix_mdev->matrix.aqm, aqm_add, AP_DOMAINS);
		bitmap_and(matrix_mdev->adm_add,
			   matrix_mdev->matrix.adm, adm_add, AP_DEVICES);
	}
}

/**
 * vfio_ap_mdev_on_cfg_add - responds to the addition of adapters, domains and
 *			     control domains to the host AP configuration
 *			     by updating the bitmaps that specify what adapters,
 *			     domains and control domains have been added so they
 *			     can be hot plugged into the guest when the AP bus
 *			     scan completes (see vfio_ap_on_scan_complete
 *			     function).
 * @cur_config_info: the current AP configuration information
 * @prev_config_info: the previous AP configuration information
 */
static void vfio_ap_mdev_on_cfg_add(struct ap_config_info *cur_config_info,
				    struct ap_config_info *prev_config_info)
{
	bool do_add;
	DECLARE_BITMAP(apm_add, AP_DEVICES);
	DECLARE_BITMAP(aqm_add, AP_DOMAINS);
	DECLARE_BITMAP(adm_add, AP_DOMAINS);

	do_add = bitmap_andnot(apm_add,
			       (unsigned long *)cur_config_info->apm,
			       (unsigned long *)prev_config_info->apm,
			       AP_DEVICES);
	do_add |= bitmap_andnot(aqm_add,
				(unsigned long *)cur_config_info->aqm,
				(unsigned long *)prev_config_info->aqm,
				AP_DOMAINS);
	do_add |= bitmap_andnot(adm_add,
				(unsigned long *)cur_config_info->adm,
				(unsigned long *)prev_config_info->adm,
				AP_DOMAINS);

	if (do_add)
		vfio_ap_mdev_cfg_add(apm_add, aqm_add, adm_add);
}

/**
 * vfio_ap_on_cfg_changed - handles notification of changes to the host AP
 *			    configuration.
 *
 * @cur_cfg_info: the current host AP configuration
 * @prev_cfg_info: the previous host AP configuration
 */
void vfio_ap_on_cfg_changed(struct ap_config_info *cur_cfg_info,
			    struct ap_config_info *prev_cfg_info)
{
	if (!cur_cfg_info || !prev_cfg_info)
		return;

	mutex_lock(&matrix_dev->guests_lock);

	vfio_ap_mdev_on_cfg_remove(cur_cfg_info, prev_cfg_info);
	vfio_ap_mdev_on_cfg_add(cur_cfg_info, prev_cfg_info);
	memcpy(&matrix_dev->info, cur_cfg_info, sizeof(*cur_cfg_info));

	mutex_unlock(&matrix_dev->guests_lock);
}

static void vfio_ap_mdev_hot_plug_cfg(struct ap_matrix_mdev *matrix_mdev)
{
	bool do_hotplug = false;
	int filter_domains = 0;
	int filter_adapters = 0;
	DECLARE_BITMAP(apm, AP_DEVICES);
	DECLARE_BITMAP(aqm, AP_DOMAINS);

	mutex_lock(&matrix_mdev->kvm->lock);
	mutex_lock(&matrix_dev->mdevs_lock);

	filter_adapters = bitmap_and(apm, matrix_mdev->matrix.apm,
				     matrix_mdev->apm_add, AP_DEVICES);
	filter_domains = bitmap_and(aqm, matrix_mdev->matrix.aqm,
				    matrix_mdev->aqm_add, AP_DOMAINS);

	if (filter_adapters && filter_domains)
		do_hotplug |= vfio_ap_mdev_filter_matrix(apm, aqm, matrix_mdev);
	else if (filter_adapters)
		do_hotplug |=
			vfio_ap_mdev_filter_matrix(apm,
						   matrix_mdev->shadow_apcb.aqm,
						   matrix_mdev);
	else
		do_hotplug |=
			vfio_ap_mdev_filter_matrix(matrix_mdev->shadow_apcb.apm,
						   aqm, matrix_mdev);

	if (bitmap_intersects(matrix_mdev->matrix.adm, matrix_mdev->adm_add,
			      AP_DOMAINS))
		do_hotplug |= vfio_ap_mdev_filter_cdoms(matrix_mdev);

	if (do_hotplug)
		vfio_ap_mdev_update_guest_apcb(matrix_mdev);

	mutex_unlock(&matrix_dev->mdevs_lock);
	mutex_unlock(&matrix_mdev->kvm->lock);
}

void vfio_ap_on_scan_complete(struct ap_config_info *new_config_info,
			      struct ap_config_info *old_config_info)
{
	struct ap_matrix_mdev *matrix_mdev;

	mutex_lock(&matrix_dev->guests_lock);

	list_for_each_entry(matrix_mdev, &matrix_dev->mdev_list, node) {
		if (bitmap_empty(matrix_mdev->apm_add, AP_DEVICES) &&
		    bitmap_empty(matrix_mdev->aqm_add, AP_DOMAINS) &&
		    bitmap_empty(matrix_mdev->adm_add, AP_DOMAINS))
			continue;

		vfio_ap_mdev_hot_plug_cfg(matrix_mdev);
		bitmap_clear(matrix_mdev->apm_add, 0, AP_DEVICES);
		bitmap_clear(matrix_mdev->aqm_add, 0, AP_DOMAINS);
		bitmap_clear(matrix_mdev->adm_add, 0, AP_DOMAINS);
	}

	mutex_unlock(&matrix_dev->guests_lock);
}