summaryrefslogtreecommitdiffstats
path: root/arch/powerpc/lib/sstep.c
blob: 5c09f365c84276161b75fd524fe270b2d43a1db2 (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
/*
 * Single-step support.
 *
 * Copyright (C) 2004 Paul Mackerras <paulus@au.ibm.com>, IBM
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 */
#include <linux/kernel.h>
#include <linux/kprobes.h>
#include <linux/ptrace.h>
#include <linux/prefetch.h>
#include <asm/sstep.h>
#include <asm/processor.h>
#include <asm/uaccess.h>
#include <asm/cputable.h>

extern char system_call_common[];

#ifdef CONFIG_PPC64
/* Bits in SRR1 that are copied from MSR */
#define MSR_MASK	0xffffffff87c0ffffUL
#else
#define MSR_MASK	0x87c0ffff
#endif

/* Bits in XER */
#define XER_SO		0x80000000U
#define XER_OV		0x40000000U
#define XER_CA		0x20000000U

#ifdef CONFIG_PPC_FPU
/*
 * Functions in ldstfp.S
 */
extern int do_lfs(int rn, unsigned long ea);
extern int do_lfd(int rn, unsigned long ea);
extern int do_stfs(int rn, unsigned long ea);
extern int do_stfd(int rn, unsigned long ea);
extern int do_lvx(int rn, unsigned long ea);
extern int do_stvx(int rn, unsigned long ea);
extern int do_lxvd2x(int rn, unsigned long ea);
extern int do_stxvd2x(int rn, unsigned long ea);
#endif

/*
 * Emulate the truncation of 64 bit values in 32-bit mode.
 */
static unsigned long truncate_if_32bit(unsigned long msr, unsigned long val)
{
#ifdef __powerpc64__
	if ((msr & MSR_64BIT) == 0)
		val &= 0xffffffffUL;
#endif
	return val;
}

/*
 * Determine whether a conditional branch instruction would branch.
 */
static int __kprobes branch_taken(unsigned int instr, struct pt_regs *regs)
{
	unsigned int bo = (instr >> 21) & 0x1f;
	unsigned int bi;

	if ((bo & 4) == 0) {
		/* decrement counter */
		--regs->ctr;
		if (((bo >> 1) & 1) ^ (regs->ctr == 0))
			return 0;
	}
	if ((bo & 0x10) == 0) {
		/* check bit from CR */
		bi = (instr >> 16) & 0x1f;
		if (((regs->ccr >> (31 - bi)) & 1) != ((bo >> 3) & 1))
			return 0;
	}
	return 1;
}


static long __kprobes address_ok(struct pt_regs *regs, unsigned long ea, int nb)
{
	if (!user_mode(regs))
		return 1;
	return __access_ok(ea, nb, USER_DS);
}

/*
 * Calculate effective address for a D-form instruction
 */
static unsigned long __kprobes dform_ea(unsigned int instr, struct pt_regs *regs)
{
	int ra;
	unsigned long ea;

	ra = (instr >> 16) & 0x1f;
	ea = (signed short) instr;		/* sign-extend */
	if (ra) {
		ea += regs->gpr[ra];
		if (instr & 0x04000000) {		/* update forms */
			if ((instr>>26) != 47) 		/* stmw is not an update form */
				regs->gpr[ra] = ea;
		}
	}

	return truncate_if_32bit(regs->msr, ea);
}

#ifdef __powerpc64__
/*
 * Calculate effective address for a DS-form instruction
 */
static unsigned long __kprobes dsform_ea(unsigned int instr, struct pt_regs *regs)
{
	int ra;
	unsigned long ea;

	ra = (instr >> 16) & 0x1f;
	ea = (signed short) (instr & ~3);	/* sign-extend */
	if (ra) {
		ea += regs->gpr[ra];
		if ((instr & 3) == 1)		/* update forms */
			regs->gpr[ra] = ea;
	}

	return truncate_if_32bit(regs->msr, ea);
}
#endif /* __powerpc64 */

/*
 * Calculate effective address for an X-form instruction
 */
static unsigned long __kprobes xform_ea(unsigned int instr, struct pt_regs *regs,
				     int do_update)
{
	int ra, rb;
	unsigned long ea;

	ra = (instr >> 16) & 0x1f;
	rb = (instr >> 11) & 0x1f;
	ea = regs->gpr[rb];
	if (ra) {
		ea += regs->gpr[ra];
		if (do_update)		/* update forms */
			regs->gpr[ra] = ea;
	}

	return truncate_if_32bit(regs->msr, ea);
}

/*
 * Return the largest power of 2, not greater than sizeof(unsigned long),
 * such that x is a multiple of it.
 */
static inline unsigned long max_align(unsigned long x)
{
	x |= sizeof(unsigned long);
	return x & -x;		/* isolates rightmost bit */
}


static inline unsigned long byterev_2(unsigned long x)
{
	return ((x >> 8) & 0xff) | ((x & 0xff) << 8);
}

static inline unsigned long byterev_4(unsigned long x)
{
	return ((x >> 24) & 0xff) | ((x >> 8) & 0xff00) |
		((x & 0xff00) << 8) | ((x & 0xff) << 24);
}

#ifdef __powerpc64__
static inline unsigned long byterev_8(unsigned long x)
{
	return (byterev_4(x) << 32) | byterev_4(x >> 32);
}
#endif

static int __kprobes read_mem_aligned(unsigned long *dest, unsigned long ea,
				      int nb)
{
	int err = 0;
	unsigned long x = 0;

	switch (nb) {
	case 1:
		err = __get_user(x, (unsigned char __user *) ea);
		break;
	case 2:
		err = __get_user(x, (unsigned short __user *) ea);
		break;
	case 4:
		err = __get_user(x, (unsigned int __user *) ea);
		break;
#ifdef __powerpc64__
	case 8:
		err = __get_user(x, (unsigned long __user *) ea);
		break;
#endif
	}
	if (!err)
		*dest = x;
	return err;
}

static int __kprobes read_mem_unaligned(unsigned long *dest, unsigned long ea,
					int nb, struct pt_regs *regs)
{
	int err;
	unsigned long x, b, c;
#ifdef __LITTLE_ENDIAN__
	int len = nb; /* save a copy of the length for byte reversal */
#endif

	/* unaligned, do this in pieces */
	x = 0;
	for (; nb > 0; nb -= c) {
#ifdef __LITTLE_ENDIAN__
		c = 1;
#endif
#ifdef __BIG_ENDIAN__
		c = max_align(ea);
#endif
		if (c > nb)
			c = max_align(nb);
		err = read_mem_aligned(&b, ea, c);
		if (err)
			return err;
		x = (x << (8 * c)) + b;
		ea += c;
	}
#ifdef __LITTLE_ENDIAN__
	switch (len) {
	case 2:
		*dest = byterev_2(x);
		break;
	case 4:
		*dest = byterev_4(x);
		break;
#ifdef __powerpc64__
	case 8:
		*dest = byterev_8(x);
		break;
#endif
	}
#endif
#ifdef __BIG_ENDIAN__
	*dest = x;
#endif
	return 0;
}

/*
 * Read memory at address ea for nb bytes, return 0 for success
 * or -EFAULT if an error occurred.
 */
static int __kprobes read_mem(unsigned long *dest, unsigned long ea, int nb,
			      struct pt_regs *regs)
{
	if (!address_ok(regs, ea, nb))
		return -EFAULT;
	if ((ea & (nb - 1)) == 0)
		return read_mem_aligned(dest, ea, nb);
	return read_mem_unaligned(dest, ea, nb, regs);
}

static int __kprobes write_mem_aligned(unsigned long val, unsigned long ea,
				       int nb)
{
	int err = 0;

	switch (nb) {
	case 1:
		err = __put_user(val, (unsigned char __user *) ea);
		break;
	case 2:
		err = __put_user(val, (unsigned short __user *) ea);
		break;
	case 4:
		err = __put_user(val, (unsigned int __user *) ea);
		break;
#ifdef __powerpc64__
	case 8:
		err = __put_user(val, (unsigned long __user *) ea);
		break;
#endif
	}
	return err;
}

static int __kprobes write_mem_unaligned(unsigned long val, unsigned long ea,
					 int nb, struct pt_regs *regs)
{
	int err;
	unsigned long c;

#ifdef __LITTLE_ENDIAN__
	switch (nb) {
	case 2:
		val = byterev_2(val);
		break;
	case 4:
		val = byterev_4(val);
		break;
#ifdef __powerpc64__
	case 8:
		val = byterev_8(val);
		break;
#endif
	}
#endif
	/* unaligned or little-endian, do this in pieces */
	for (; nb > 0; nb -= c) {
#ifdef __LITTLE_ENDIAN__
		c = 1;
#endif
#ifdef __BIG_ENDIAN__
		c = max_align(ea);
#endif
		if (c > nb)
			c = max_align(nb);
		err = write_mem_aligned(val >> (nb - c) * 8, ea, c);
		if (err)
			return err;
		ea += c;
	}
	return 0;
}

/*
 * Write memory at address ea for nb bytes, return 0 for success
 * or -EFAULT if an error occurred.
 */
static int __kprobes write_mem(unsigned long val, unsigned long ea, int nb,
			       struct pt_regs *regs)
{
	if (!address_ok(regs, ea, nb))
		return -EFAULT;
	if ((ea & (nb - 1)) == 0)
		return write_mem_aligned(val, ea, nb);
	return write_mem_unaligned(val, ea, nb, regs);
}

#ifdef CONFIG_PPC_FPU
/*
 * Check the address and alignment, and call func to do the actual
 * load or store.
 */
static int __kprobes do_fp_load(int rn, int (*func)(int, unsigned long),
				unsigned long ea, int nb,
				struct pt_regs *regs)
{
	int err;
	union {
		double dbl;
		unsigned long ul[2];
		struct {
#ifdef __BIG_ENDIAN__
			unsigned _pad_;
			unsigned word;
#endif
#ifdef __LITTLE_ENDIAN__
			unsigned word;
			unsigned _pad_;
#endif
		} single;
	} data;
	unsigned long ptr;

	if (!address_ok(regs, ea, nb))
		return -EFAULT;
	if ((ea & 3) == 0)
		return (*func)(rn, ea);
	ptr = (unsigned long) &data.ul;
	if (sizeof(unsigned long) == 8 || nb == 4) {
		err = read_mem_unaligned(&data.ul[0], ea, nb, regs);
		if (nb == 4)
			ptr = (unsigned long)&(data.single.word);
	} else {
		/* reading a double on 32-bit */
		err = read_mem_unaligned(&data.ul[0], ea, 4, regs);
		if (!err)
			err = read_mem_unaligned(&data.ul[1], ea + 4, 4, regs);
	}
	if (err)
		return err;
	return (*func)(rn, ptr);
}

static int __kprobes do_fp_store(int rn, int (*func)(int, unsigned long),
				 unsigned long ea, int nb,
				 struct pt_regs *regs)
{
	int err;
	union {
		double dbl;
		unsigned long ul[2];
		struct {
#ifdef __BIG_ENDIAN__
			unsigned _pad_;
			unsigned word;
#endif
#ifdef __LITTLE_ENDIAN__
			unsigned word;
			unsigned _pad_;
#endif
		} single;
	} data;
	unsigned long ptr;

	if (!address_ok(regs, ea, nb))
		return -EFAULT;
	if ((ea & 3) == 0)
		return (*func)(rn, ea);
	ptr = (unsigned long) &data.ul[0];
	if (sizeof(unsigned long) == 8 || nb == 4) {
		if (nb == 4)
			ptr = (unsigned long)&(data.single.word);
		err = (*func)(rn, ptr);
		if (err)
			return err;
		err = write_mem_unaligned(data.ul[0], ea, nb, regs);
	} else {
		/* writing a double on 32-bit */
		err = (*func)(rn, ptr);
		if (err)
			return err;
		err = write_mem_unaligned(data.ul[0], ea, 4, regs);
		if (!err)
			err = write_mem_unaligned(data.ul[1], ea + 4, 4, regs);
	}
	return err;
}
#endif

#ifdef CONFIG_ALTIVEC
/* For Altivec/VMX, no need to worry about alignment */
static int __kprobes do_vec_load(int rn, int (*func)(int, unsigned long),
				 unsigned long ea, struct pt_regs *regs)
{
	if (!address_ok(regs, ea & ~0xfUL, 16))
		return -EFAULT;
	return (*func)(rn, ea);
}

static int __kprobes do_vec_store(int rn, int (*func)(int, unsigned long),
				  unsigned long ea, struct pt_regs *regs)
{
	if (!address_ok(regs, ea & ~0xfUL, 16))
		return -EFAULT;
	return (*func)(rn, ea);
}
#endif /* CONFIG_ALTIVEC */

#ifdef CONFIG_VSX
static int __kprobes do_vsx_load(int rn, int (*func)(int, unsigned long),
				 unsigned long ea, struct pt_regs *regs)
{
	int err;
	unsigned long val[2];

	if (!address_ok(regs, ea, 16))
		return -EFAULT;
	if ((ea & 3) == 0)
		return (*func)(rn, ea);
	err = read_mem_unaligned(&val[0], ea, 8, regs);
	if (!err)
		err = read_mem_unaligned(&val[1], ea + 8, 8, regs);
	if (!err)
		err = (*func)(rn, (unsigned long) &val[0]);
	return err;
}

static int __kprobes do_vsx_store(int rn, int (*func)(int, unsigned long),
				 unsigned long ea, struct pt_regs *regs)
{
	int err;
	unsigned long val[2];

	if (!address_ok(regs, ea, 16))
		return -EFAULT;
	if ((ea & 3) == 0)
		return (*func)(rn, ea);
	err = (*func)(rn, (unsigned long) &val[0]);
	if (err)
		return err;
	err = write_mem_unaligned(val[0], ea, 8, regs);
	if (!err)
		err = write_mem_unaligned(val[1], ea + 8, 8, regs);
	return err;
}
#endif /* CONFIG_VSX */

#define __put_user_asmx(x, addr, err, op, cr)		\
	__asm__ __volatile__(				\
		"1:	" op " %2,0,%3\n"		\
		"	mfcr	%1\n"			\
		"2:\n"					\
		".section .fixup,\"ax\"\n"		\
		"3:	li	%0,%4\n"		\
		"	b	2b\n"			\
		".previous\n"				\
		".section __ex_table,\"a\"\n"		\
			PPC_LONG_ALIGN "\n"		\
			PPC_LONG "1b,3b\n"		\
		".previous"				\
		: "=r" (err), "=r" (cr)			\
		: "r" (x), "r" (addr), "i" (-EFAULT), "0" (err))

#define __get_user_asmx(x, addr, err, op)		\
	__asm__ __volatile__(				\
		"1:	"op" %1,0,%2\n"			\
		"2:\n"					\
		".section .fixup,\"ax\"\n"		\
		"3:	li	%0,%3\n"		\
		"	b	2b\n"			\
		".previous\n"				\
		".section __ex_table,\"a\"\n"		\
			PPC_LONG_ALIGN "\n"		\
			PPC_LONG "1b,3b\n"		\
		".previous"				\
		: "=r" (err), "=r" (x)			\
		: "r" (addr), "i" (-EFAULT), "0" (err))

#define __cacheop_user_asmx(addr, err, op)		\
	__asm__ __volatile__(				\
		"1:	"op" 0,%1\n"			\
		"2:\n"					\
		".section .fixup,\"ax\"\n"		\
		"3:	li	%0,%3\n"		\
		"	b	2b\n"			\
		".previous\n"				\
		".section __ex_table,\"a\"\n"		\
			PPC_LONG_ALIGN "\n"		\
			PPC_LONG "1b,3b\n"		\
		".previous"				\
		: "=r" (err)				\
		: "r" (addr), "i" (-EFAULT), "0" (err))

static void __kprobes set_cr0(struct pt_regs *regs, int rd)
{
	long val = regs->gpr[rd];

	regs->ccr = (regs->ccr & 0x0fffffff) | ((regs->xer >> 3) & 0x10000000);
#ifdef __powerpc64__
	if (!(regs->msr & MSR_64BIT))
		val = (int) val;
#endif
	if (val < 0)
		regs->ccr |= 0x80000000;
	else if (val > 0)
		regs->ccr |= 0x40000000;
	else
		regs->ccr |= 0x20000000;
}

static void __kprobes add_with_carry(struct pt_regs *regs, int rd,
				     unsigned long val1, unsigned long val2,
				     unsigned long carry_in)
{
	unsigned long val = val1 + val2;

	if (carry_in)
		++val;
	regs->gpr[rd] = val;
#ifdef __powerpc64__
	if (!(regs->msr & MSR_64BIT)) {
		val = (unsigned int) val;
		val1 = (unsigned int) val1;
	}
#endif
	if (val < val1 || (carry_in && val == val1))
		regs->xer |= XER_CA;
	else
		regs->xer &= ~XER_CA;
}

static void __kprobes do_cmp_signed(struct pt_regs *regs, long v1, long v2,
				    int crfld)
{
	unsigned int crval, shift;

	crval = (regs->xer >> 31) & 1;		/* get SO bit */
	if (v1 < v2)
		crval |= 8;
	else if (v1 > v2)
		crval |= 4;
	else
		crval |= 2;
	shift = (7 - crfld) * 4;
	regs->ccr = (regs->ccr & ~(0xf << shift)) | (crval << shift);
}

static void __kprobes do_cmp_unsigned(struct pt_regs *regs, unsigned long v1,
				      unsigned long v2, int crfld)
{
	unsigned int crval, shift;

	crval = (regs->xer >> 31) & 1;		/* get SO bit */
	if (v1 < v2)
		crval |= 8;
	else if (v1 > v2)
		crval |= 4;
	else
		crval |= 2;
	shift = (7 - crfld) * 4;
	regs->ccr = (regs->ccr & ~(0xf << shift)) | (crval << shift);
}

/*
 * Elements of 32-bit rotate and mask instructions.
 */
#define MASK32(mb, me)	((0xffffffffUL >> (mb)) + \
			 ((signed long)-0x80000000L >> (me)) + ((me) >= (mb)))
#ifdef __powerpc64__
#define MASK64_L(mb)	(~0UL >> (mb))
#define MASK64_R(me)	((signed long)-0x8000000000000000L >> (me))
#define MASK64(mb, me)	(MASK64_L(mb) + MASK64_R(me) + ((me) >= (mb)))
#define DATA32(x)	(((x) & 0xffffffffUL) | (((x) & 0xffffffffUL) << 32))
#else
#define DATA32(x)	(x)
#endif
#define ROTATE(x, n)	((n) ? (((x) << (n)) | ((x) >> (8 * sizeof(long) - (n)))) : (x))

/*
 * Emulate instructions that cause a transfer of control,
 * loads and stores, and a few other instructions.
 * Returns 1 if the step was emulated, 0 if not,
 * or -1 if the instruction is one that should not be stepped,
 * such as an rfid, or a mtmsrd that would clear MSR_RI.
 */
int __kprobes emulate_step(struct pt_regs *regs, unsigned int instr)
{
	unsigned int opcode, ra, rb, rd, spr, u;
	unsigned long int imm;
	unsigned long int val, val2;
	unsigned long int ea;
	unsigned int cr, mb, me, sh;
	int err;
	unsigned long old_ra, val3;
	long ival;

	opcode = instr >> 26;
	switch (opcode) {
	case 16:	/* bc */
		imm = (signed short)(instr & 0xfffc);
		if ((instr & 2) == 0)
			imm += regs->nip;
		regs->nip += 4;
		regs->nip = truncate_if_32bit(regs->msr, regs->nip);
		if (instr & 1)
			regs->link = regs->nip;
		if (branch_taken(instr, regs))
			regs->nip = truncate_if_32bit(regs->msr, imm);
		return 1;
#ifdef CONFIG_PPC64
	case 17:	/* sc */
		/*
		 * N.B. this uses knowledge about how the syscall
		 * entry code works.  If that is changed, this will
		 * need to be changed also.
		 */
		if (regs->gpr[0] == 0x1ebe &&
		    cpu_has_feature(CPU_FTR_REAL_LE)) {
			regs->msr ^= MSR_LE;
			goto instr_done;
		}
		regs->gpr[9] = regs->gpr[13];
		regs->gpr[10] = MSR_KERNEL;
		regs->gpr[11] = regs->nip + 4;
		regs->gpr[12] = regs->msr & MSR_MASK;
		regs->gpr[13] = (unsigned long) get_paca();
		regs->nip = (unsigned long) &system_call_common;
		regs->msr = MSR_KERNEL;
		return 1;
#endif
	case 18:	/* b */
		imm = instr & 0x03fffffc;
		if (imm & 0x02000000)
			imm -= 0x04000000;
		if ((instr & 2) == 0)
			imm += regs->nip;
		if (instr & 1)
			regs->link = truncate_if_32bit(regs->msr, regs->nip + 4);
		imm = truncate_if_32bit(regs->msr, imm);
		regs->nip = imm;
		return 1;
	case 19:
		switch ((instr >> 1) & 0x3ff) {
		case 16:	/* bclr */
		case 528:	/* bcctr */
			imm = (instr & 0x400)? regs->ctr: regs->link;
			regs->nip = truncate_if_32bit(regs->msr, regs->nip + 4);
			imm = truncate_if_32bit(regs->msr, imm);
			if (instr & 1)
				regs->link = regs->nip;
			if (branch_taken(instr, regs))
				regs->nip = imm;
			return 1;

		case 18:	/* rfid, scary */
			return -1;

		case 150:	/* isync */
			isync();
			goto instr_done;

		case 33:	/* crnor */
		case 129:	/* crandc */
		case 193:	/* crxor */
		case 225:	/* crnand */
		case 257:	/* crand */
		case 289:	/* creqv */
		case 417:	/* crorc */
		case 449:	/* cror */
			ra = (instr >> 16) & 0x1f;
			rb = (instr >> 11) & 0x1f;
			rd = (instr >> 21) & 0x1f;
			ra = (regs->ccr >> (31 - ra)) & 1;
			rb = (regs->ccr >> (31 - rb)) & 1;
			val = (instr >> (6 + ra * 2 + rb)) & 1;
			regs->ccr = (regs->ccr & ~(1UL << (31 - rd))) |
				(val << (31 - rd));
			goto instr_done;
		}
		break;
	case 31:
		switch ((instr >> 1) & 0x3ff) {
		case 598:	/* sync */
#ifdef __powerpc64__
			switch ((instr >> 21) & 3) {
			case 1:		/* lwsync */
				asm volatile("lwsync" : : : "memory");
				goto instr_done;
			case 2:		/* ptesync */
				asm volatile("ptesync" : : : "memory");
				goto instr_done;
			}
#endif
			mb();
			goto instr_done;

		case 854:	/* eieio */
			eieio();
			goto instr_done;
		}
		break;
	}

	/* Following cases refer to regs->gpr[], so we need all regs */
	if (!FULL_REGS(regs))
		return 0;

	rd = (instr >> 21) & 0x1f;
	ra = (instr >> 16) & 0x1f;
	rb = (instr >> 11) & 0x1f;

	switch (opcode) {
	case 7:		/* mulli */
		regs->gpr[rd] = regs->gpr[ra] * (short) instr;
		goto instr_done;

	case 8:		/* subfic */
		imm = (short) instr;
		add_with_carry(regs, rd, ~regs->gpr[ra], imm, 1);
		goto instr_done;

	case 10:	/* cmpli */
		imm = (unsigned short) instr;
		val = regs->gpr[ra];
#ifdef __powerpc64__
		if ((rd & 1) == 0)
			val = (unsigned int) val;
#endif
		do_cmp_unsigned(regs, val, imm, rd >> 2);
		goto instr_done;

	case 11:	/* cmpi */
		imm = (short) instr;
		val = regs->gpr[ra];
#ifdef __powerpc64__
		if ((rd & 1) == 0)
			val = (int) val;
#endif
		do_cmp_signed(regs, val, imm, rd >> 2);
		goto instr_done;

	case 12:	/* addic */
		imm = (short) instr;
		add_with_carry(regs, rd, regs->gpr[ra], imm, 0);
		goto instr_done;

	case 13:	/* addic. */
		imm = (short) instr;
		add_with_carry(regs, rd, regs->gpr[ra], imm, 0);
		set_cr0(regs, rd);
		goto instr_done;

	case 14:	/* addi */
		imm = (short) instr;
		if (ra)
			imm += regs->gpr[ra];
		regs->gpr[rd] = imm;
		goto instr_done;

	case 15:	/* addis */
		imm = ((short) instr) << 16;
		if (ra)
			imm += regs->gpr[ra];
		regs->gpr[rd] = imm;
		goto instr_done;

	case 20:	/* rlwimi */
		mb = (instr >> 6) & 0x1f;
		me = (instr >> 1) & 0x1f;
		val = DATA32(regs->gpr[rd]);
		imm = MASK32(mb, me);
		regs->gpr[ra] = (regs->gpr[ra] & ~imm) | (ROTATE(val, rb) & imm);
		goto logical_done;

	case 21:	/* rlwinm */
		mb = (instr >> 6) & 0x1f;
		me = (instr >> 1) & 0x1f;
		val = DATA32(regs->gpr[rd]);
		regs->gpr[ra] = ROTATE(val, rb) & MASK32(mb, me);
		goto logical_done;

	case 23:	/* rlwnm */
		mb = (instr >> 6) & 0x1f;
		me = (instr >> 1) & 0x1f;
		rb = regs->gpr[rb] & 0x1f;
		val = DATA32(regs->gpr[rd]);
		regs->gpr[ra] = ROTATE(val, rb) & MASK32(mb, me);
		goto logical_done;

	case 24:	/* ori */
		imm = (unsigned short) instr;
		regs->gpr[ra] = regs->gpr[rd] | imm;
		goto instr_done;

	case 25:	/* oris */
		imm = (unsigned short) instr;
		regs->gpr[ra] = regs->gpr[rd] | (imm << 16);
		goto instr_done;

	case 26:	/* xori */
		imm = (unsigned short) instr;
		regs->gpr[ra] = regs->gpr[rd] ^ imm;
		goto instr_done;

	case 27:	/* xoris */
		imm = (unsigned short) instr;
		regs->gpr[ra] = regs->gpr[rd] ^ (imm << 16);
		goto instr_done;

	case 28:	/* andi. */
		imm = (unsigned short) instr;
		regs->gpr[ra] = regs->gpr[rd] & imm;
		set_cr0(regs, ra);
		goto instr_done;

	case 29:	/* andis. */
		imm = (unsigned short) instr;
		regs->gpr[ra] = regs->gpr[rd] & (imm << 16);
		set_cr0(regs, ra);
		goto instr_done;

#ifdef __powerpc64__
	case 30:	/* rld* */
		mb = ((instr >> 6) & 0x1f) | (instr & 0x20);
		val = regs->gpr[rd];
		if ((instr & 0x10) == 0) {
			sh = rb | ((instr & 2) << 4);
			val = ROTATE(val, sh);
			switch ((instr >> 2) & 3) {
			case 0:		/* rldicl */
				regs->gpr[ra] = val & MASK64_L(mb);
				goto logical_done;
			case 1:		/* rldicr */
				regs->gpr[ra] = val & MASK64_R(mb);
				goto logical_done;
			case 2:		/* rldic */
				regs->gpr[ra] = val & MASK64(mb, 63 - sh);
				goto logical_done;
			case 3:		/* rldimi */
				imm = MASK64(mb, 63 - sh);
				regs->gpr[ra] = (regs->gpr[ra] & ~imm) |
					(val & imm);
				goto logical_done;
			}
		} else {
			sh = regs->gpr[rb] & 0x3f;
			val = ROTATE(val, sh);
			switch ((instr >> 1) & 7) {
			case 0:		/* rldcl */
				regs->gpr[ra] = val & MASK64_L(mb);
				goto logical_done;
			case 1:		/* rldcr */
				regs->gpr[ra] = val & MASK64_R(mb);
				goto logical_done;
			}
		}
#endif

	case 31:
		switch ((instr >> 1) & 0x3ff) {
		case 83:	/* mfmsr */
			if (regs->msr & MSR_PR)
				break;
			regs->gpr[rd] = regs->msr & MSR_MASK;
			goto instr_done;
		case 146:	/* mtmsr */
			if (regs->msr & MSR_PR)
				break;
			imm = regs->gpr[rd];
			if ((imm & MSR_RI) == 0)
				/* can't step mtmsr that would clear MSR_RI */
				return -1;
			regs->msr = imm;
			goto instr_done;
#ifdef CONFIG_PPC64
		case 178:	/* mtmsrd */
			/* only MSR_EE and MSR_RI get changed if bit 15 set */
			/* mtmsrd doesn't change MSR_HV and MSR_ME */
			if (regs->msr & MSR_PR)
				break;
			imm = (instr & 0x10000)? 0x8002: 0xefffffffffffefffUL;
			imm = (regs->msr & MSR_MASK & ~imm)
				| (regs->gpr[rd] & imm);
			if ((imm & MSR_RI) == 0)
				/* can't step mtmsrd that would clear MSR_RI */
				return -1;
			regs->msr = imm;
			goto instr_done;
#endif
		case 19:	/* mfcr */
			regs->gpr[rd] = regs->ccr;
			regs->gpr[rd] &= 0xffffffffUL;
			goto instr_done;

		case 144:	/* mtcrf */
			imm = 0xf0000000UL;
			val = regs->gpr[rd];
			for (sh = 0; sh < 8; ++sh) {
				if (instr & (0x80000 >> sh))
					regs->ccr = (regs->ccr & ~imm) |
						(val & imm);
				imm >>= 4;
			}
			goto instr_done;

		case 339:	/* mfspr */
			spr = (instr >> 11) & 0x3ff;
			switch (spr) {
			case 0x20:	/* mfxer */
				regs->gpr[rd] = regs->xer;
				regs->gpr[rd] &= 0xffffffffUL;
				goto instr_done;
			case 0x100:	/* mflr */
				regs->gpr[rd] = regs->link;
				goto instr_done;
			case 0x120:	/* mfctr */
				regs->gpr[rd] = regs->ctr;
				goto instr_done;
			}
			break;

		case 467:	/* mtspr */
			spr = (instr >> 11) & 0x3ff;
			switch (spr) {
			case 0x20:	/* mtxer */
				regs->xer = (regs->gpr[rd] & 0xffffffffUL);
				goto instr_done;
			case 0x100:	/* mtlr */
				regs->link = regs->gpr[rd];
				goto instr_done;
			case 0x120:	/* mtctr */
				regs->ctr = regs->gpr[rd];
				goto instr_done;
			}
			break;

/*
 * Compare instructions
 */
		case 0:	/* cmp */
			val = regs->gpr[ra];
			val2 = regs->gpr[rb];
#ifdef __powerpc64__
			if ((rd & 1) == 0) {
				/* word (32-bit) compare */
				val = (int) val;
				val2 = (int) val2;
			}
#endif
			do_cmp_signed(regs, val, val2, rd >> 2);
			goto instr_done;

		case 32:	/* cmpl */
			val = regs->gpr[ra];
			val2 = regs->gpr[rb];
#ifdef __powerpc64__
			if ((rd & 1) == 0) {
				/* word (32-bit) compare */
				val = (unsigned int) val;
				val2 = (unsigned int) val2;
			}
#endif
			do_cmp_unsigned(regs, val, val2, rd >> 2);
			goto instr_done;

/*
 * Arithmetic instructions
 */
		case 8:	/* subfc */
			add_with_carry(regs, rd, ~regs->gpr[ra],
				       regs->gpr[rb], 1);
			goto arith_done;
#ifdef __powerpc64__
		case 9:	/* mulhdu */
			asm("mulhdu %0,%1,%2" : "=r" (regs->gpr[rd]) :
			    "r" (regs->gpr[ra]), "r" (regs->gpr[rb]));
			goto arith_done;
#endif
		case 10:	/* addc */
			add_with_carry(regs, rd, regs->gpr[ra],
				       regs->gpr[rb], 0);
			goto arith_done;

		case 11:	/* mulhwu */
			asm("mulhwu %0,%1,%2" : "=r" (regs->gpr[rd]) :
			    "r" (regs->gpr[ra]), "r" (regs->gpr[rb]));
			goto arith_done;

		case 40:	/* subf */
			regs->gpr[rd] = regs->gpr[rb] - regs->gpr[ra];
			goto arith_done;
#ifdef __powerpc64__
		case 73:	/* mulhd */
			asm("mulhd %0,%1,%2" : "=r" (regs->gpr[rd]) :
			    "r" (regs->gpr[ra]), "r" (regs->gpr[rb]));
			goto arith_done;
#endif
		case 75:	/* mulhw */
			asm("mulhw %0,%1,%2" : "=r" (regs->gpr[rd]) :
			    "r" (regs->gpr[ra]), "r" (regs->gpr[rb]));
			goto arith_done;

		case 104:	/* neg */
			regs->gpr[rd] = -regs->gpr[ra];
			goto arith_done;

		case 136:	/* subfe */
			add_with_carry(regs, rd, ~regs->gpr[ra], regs->gpr[rb],
				       regs->xer & XER_CA);
			goto arith_done;

		case 138:	/* adde */
			add_with_carry(regs, rd, regs->gpr[ra], regs->gpr[rb],
				       regs->xer & XER_CA);
			goto arith_done;

		case 200:	/* subfze */
			add_with_carry(regs, rd, ~regs->gpr[ra], 0L,
				       regs->xer & XER_CA);
			goto arith_done;

		case 202:	/* addze */
			add_with_carry(regs, rd, regs->gpr[ra], 0L,
				       regs->xer & XER_CA);
			goto arith_done;

		case 232:	/* subfme */
			add_with_carry(regs, rd, ~regs->gpr[ra], -1L,
				       regs->xer & XER_CA);
			goto arith_done;
#ifdef __powerpc64__
		case 233:	/* mulld */
			regs->gpr[rd] = regs->gpr[ra] * regs->gpr[rb];
			goto arith_done;
#endif
		case 234:	/* addme */
			add_with_carry(regs, rd, regs->gpr[ra], -1L,
				       regs->xer & XER_CA);
			goto arith_done;

		case 235:	/* mullw */
			regs->gpr[rd] = (unsigned int) regs->gpr[ra] *
				(unsigned int) regs->gpr[rb];
			goto arith_done;

		case 266:	/* add */
			regs->gpr[rd] = regs->gpr[ra] + regs->gpr[rb];
			goto arith_done;
#ifdef __powerpc64__
		case 457:	/* divdu */
			regs->gpr[rd] = regs->gpr[ra] / regs->gpr[rb];
			goto arith_done;
#endif
		case 459:	/* divwu */
			regs->gpr[rd] = (unsigned int) regs->gpr[ra] /
				(unsigned int) regs->gpr[rb];
			goto arith_done;
#ifdef __powerpc64__
		case 489:	/* divd */
			regs->gpr[rd] = (long int) regs->gpr[ra] /
				(long int) regs->gpr[rb];
			goto arith_done;
#endif
		case 491:	/* divw */
			regs->gpr[rd] = (int) regs->gpr[ra] /
				(int) regs->gpr[rb];
			goto arith_done;


/*
 * Logical instructions
 */
		case 26:	/* cntlzw */
			asm("cntlzw %0,%1" : "=r" (regs->gpr[ra]) :
			    "r" (regs->gpr[rd]));
			goto logical_done;
#ifdef __powerpc64__
		case 58:	/* cntlzd */
			asm("cntlzd %0,%1" : "=r" (regs->gpr[ra]) :
			    "r" (regs->gpr[rd]));
			goto logical_done;
#endif
		case 28:	/* and */
			regs->gpr[ra] = regs->gpr[rd] & regs->gpr[rb];
			goto logical_done;

		case 60:	/* andc */
			regs->gpr[ra] = regs->gpr[rd] & ~regs->gpr[rb];
			goto logical_done;

		case 124:	/* nor */
			regs->gpr[ra] = ~(regs->gpr[rd] | regs->gpr[rb]);
			goto logical_done;

		case 284:	/* xor */
			regs->gpr[ra] = ~(regs->gpr[rd] ^ regs->gpr[rb]);
			goto logical_done;

		case 316:	/* xor */
			regs->gpr[ra] = regs->gpr[rd] ^ regs->gpr[rb];
			goto logical_done;

		case 412:	/* orc */
			regs->gpr[ra] = regs->gpr[rd] | ~regs->gpr[rb];
			goto logical_done;

		case 444:	/* or */
			regs->gpr[ra] = regs->gpr[rd] | regs->gpr[rb];
			goto logical_done;

		case 476:	/* nand */
			regs->gpr[ra] = ~(regs->gpr[rd] & regs->gpr[rb]);
			goto logical_done;

		case 922:	/* extsh */
			regs->gpr[ra] = (signed short) regs->gpr[rd];
			goto logical_done;

		case 954:	/* extsb */
			regs->gpr[ra] = (signed char) regs->gpr[rd];
			goto logical_done;
#ifdef __powerpc64__
		case 986:	/* extsw */
			regs->gpr[ra] = (signed int) regs->gpr[rd];
			goto logical_done;
#endif

/*
 * Shift instructions
 */
		case 24:	/* slw */
			sh = regs->gpr[rb] & 0x3f;
			if (sh < 32)
				regs->gpr[ra] = (regs->gpr[rd] << sh) & 0xffffffffUL;
			else
				regs->gpr[ra] = 0;
			goto logical_done;

		case 536:	/* srw */
			sh = regs->gpr[rb] & 0x3f;
			if (sh < 32)
				regs->gpr[ra] = (regs->gpr[rd] & 0xffffffffUL) >> sh;
			else
				regs->gpr[ra] = 0;
			goto logical_done;

		case 792:	/* sraw */
			sh = regs->gpr[rb] & 0x3f;
			ival = (signed int) regs->gpr[rd];
			regs->gpr[ra] = ival >> (sh < 32 ? sh : 31);
			if (ival < 0 && (sh >= 32 || (ival & ((1ul << sh) - 1)) != 0))
				regs->xer |= XER_CA;
			else
				regs->xer &= ~XER_CA;
			goto logical_done;

		case 824:	/* srawi */
			sh = rb;
			ival = (signed int) regs->gpr[rd];
			regs->gpr[ra] = ival >> sh;
			if (ival < 0 && (ival & ((1ul << sh) - 1)) != 0)
				regs->xer |= XER_CA;
			else
				regs->xer &= ~XER_CA;
			goto logical_done;

#ifdef __powerpc64__
		case 27:	/* sld */
			sh = regs->gpr[rb] & 0x7f;
			if (sh < 64)
				regs->gpr[ra] = regs->gpr[rd] << sh;
			else
				regs->gpr[ra] = 0;
			goto logical_done;

		case 539:	/* srd */
			sh = regs->gpr[rb] & 0x7f;
			if (sh < 64)
				regs->gpr[ra] = regs->gpr[rd] >> sh;
			else
				regs->gpr[ra] = 0;
			goto logical_done;

		case 794:	/* srad */
			sh = regs->gpr[rb] & 0x7f;
			ival = (signed long int) regs->gpr[rd];
			regs->gpr[ra] = ival >> (sh < 64 ? sh : 63);
			if (ival < 0 && (sh >= 64 || (ival & ((1ul << sh) - 1)) != 0))
				regs->xer |= XER_CA;
			else
				regs->xer &= ~XER_CA;
			goto logical_done;

		case 826:	/* sradi with sh_5 = 0 */
		case 827:	/* sradi with sh_5 = 1 */
			sh = rb | ((instr & 2) << 4);
			ival = (signed long int) regs->gpr[rd];
			regs->gpr[ra] = ival >> sh;
			if (ival < 0 && (ival & ((1ul << sh) - 1)) != 0)
				regs->xer |= XER_CA;
			else
				regs->xer &= ~XER_CA;
			goto logical_done;
#endif /* __powerpc64__ */

/*
 * Cache instructions
 */
		case 54:	/* dcbst */
			ea = xform_ea(instr, regs, 0);
			if (!address_ok(regs, ea, 8))
				return 0;
			err = 0;
			__cacheop_user_asmx(ea, err, "dcbst");
			if (err)
				return 0;
			goto instr_done;

		case 86:	/* dcbf */
			ea = xform_ea(instr, regs, 0);
			if (!address_ok(regs, ea, 8))
				return 0;
			err = 0;
			__cacheop_user_asmx(ea, err, "dcbf");
			if (err)
				return 0;
			goto instr_done;

		case 246:	/* dcbtst */
			if (rd == 0) {
				ea = xform_ea(instr, regs, 0);
				prefetchw((void *) ea);
			}
			goto instr_done;

		case 278:	/* dcbt */
			if (rd == 0) {
				ea = xform_ea(instr, regs, 0);
				prefetch((void *) ea);
			}
			goto instr_done;

		}
		break;
	}

	/*
	 * Following cases are for loads and stores, so bail out
	 * if we're in little-endian mode.
	 */
	if (regs->msr & MSR_LE)
		return 0;

	/*
	 * Save register RA in case it's an update form load or store
	 * and the access faults.
	 */
	old_ra = regs->gpr[ra];

	switch (opcode) {
	case 31:
		u = instr & 0x40;
		switch ((instr >> 1) & 0x3ff) {
		case 20:	/* lwarx */
			ea = xform_ea(instr, regs, 0);
			if (ea & 3)
				break;		/* can't handle misaligned */
			err = -EFAULT;
			if (!address_ok(regs, ea, 4))
				goto ldst_done;
			err = 0;
			__get_user_asmx(val, ea, err, "lwarx");
			if (!err)
				regs->gpr[rd] = val;
			goto ldst_done;

		case 150:	/* stwcx. */
			ea = xform_ea(instr, regs, 0);
			if (ea & 3)
				break;		/* can't handle misaligned */
			err = -EFAULT;
			if (!address_ok(regs, ea, 4))
				goto ldst_done;
			err = 0;
			__put_user_asmx(regs->gpr[rd], ea, err, "stwcx.", cr);
			if (!err)
				regs->ccr = (regs->ccr & 0x0fffffff) |
					(cr & 0xe0000000) |
					((regs->xer >> 3) & 0x10000000);
			goto ldst_done;

#ifdef __powerpc64__
		case 84:	/* ldarx */
			ea = xform_ea(instr, regs, 0);
			if (ea & 7)
				break;		/* can't handle misaligned */
			err = -EFAULT;
			if (!address_ok(regs, ea, 8))
				goto ldst_done;
			err = 0;
			__get_user_asmx(val, ea, err, "ldarx");
			if (!err)
				regs->gpr[rd] = val;
			goto ldst_done;

		case 214:	/* stdcx. */
			ea = xform_ea(instr, regs, 0);
			if (ea & 7)
				break;		/* can't handle misaligned */
			err = -EFAULT;
			if (!address_ok(regs, ea, 8))
				goto ldst_done;
			err = 0;
			__put_user_asmx(regs->gpr[rd], ea, err, "stdcx.", cr);
			if (!err)
				regs->ccr = (regs->ccr & 0x0fffffff) |
					(cr & 0xe0000000) |
					((regs->xer >> 3) & 0x10000000);
			goto ldst_done;

		case 21:	/* ldx */
		case 53:	/* ldux */
			err = read_mem(&regs->gpr[rd], xform_ea(instr, regs, u),
				       8, regs);
			goto ldst_done;
#endif

		case 23:	/* lwzx */
		case 55:	/* lwzux */
			err = read_mem(&regs->gpr[rd], xform_ea(instr, regs, u),
				       4, regs);
			goto ldst_done;

		case 87:	/* lbzx */
		case 119:	/* lbzux */
			err = read_mem(&regs->gpr[rd], xform_ea(instr, regs, u),
				       1, regs);
			goto ldst_done;

#ifdef CONFIG_ALTIVEC
		case 103:	/* lvx */
		case 359:	/* lvxl */
			if (!(regs->msr & MSR_VEC))
				break;
			ea = xform_ea(instr, regs, 0);
			err = do_vec_load(rd, do_lvx, ea, regs);
			goto ldst_done;

		case 231:	/* stvx */
		case 487:	/* stvxl */
			if (!(regs->msr & MSR_VEC))
				break;
			ea = xform_ea(instr, regs, 0);
			err = do_vec_store(rd, do_stvx, ea, regs);
			goto ldst_done;
#endif /* CONFIG_ALTIVEC */

#ifdef __powerpc64__
		case 149:	/* stdx */
		case 181:	/* stdux */
			val = regs->gpr[rd];
			err = write_mem(val, xform_ea(instr, regs, u), 8, regs);
			goto ldst_done;
#endif

		case 151:	/* stwx */
		case 183:	/* stwux */
			val = regs->gpr[rd];
			err = write_mem(val, xform_ea(instr, regs, u), 4, regs);
			goto ldst_done;

		case 215:	/* stbx */
		case 247:	/* stbux */
			val = regs->gpr[rd];
			err = write_mem(val, xform_ea(instr, regs, u), 1, regs);
			goto ldst_done;

		case 279:	/* lhzx */
		case 311:	/* lhzux */
			err = read_mem(&regs->gpr[rd], xform_ea(instr, regs, u),
				       2, regs);
			goto ldst_done;

#ifdef __powerpc64__
		case 341:	/* lwax */
		case 373:	/* lwaux */
			err = read_mem(&regs->gpr[rd], xform_ea(instr, regs, u),
				       4, regs);
			if (!err)
				regs->gpr[rd] = (signed int) regs->gpr[rd];
			goto ldst_done;
#endif

		case 343:	/* lhax */
		case 375:	/* lhaux */
			err = read_mem(&regs->gpr[rd], xform_ea(instr, regs, u),
				       2, regs);
			if (!err)
				regs->gpr[rd] = (signed short) regs->gpr[rd];
			goto ldst_done;

		case 407:	/* sthx */
		case 439:	/* sthux */
			val = regs->gpr[rd];
			err = write_mem(val, xform_ea(instr, regs, u), 2, regs);
			goto ldst_done;

#ifdef __powerpc64__
		case 532:	/* ldbrx */
			err = read_mem(&val, xform_ea(instr, regs, 0), 8, regs);
			if (!err)
				regs->gpr[rd] = byterev_8(val);
			goto ldst_done;

#endif

		case 534:	/* lwbrx */
			err = read_mem(&val, xform_ea(instr, regs, 0), 4, regs);
			if (!err)
				regs->gpr[rd] = byterev_4(val);
			goto ldst_done;

#ifdef CONFIG_PPC_FPU
		case 535:	/* lfsx */
		case 567:	/* lfsux */
			if (!(regs->msr & MSR_FP))
				break;
			ea = xform_ea(instr, regs, u);
			err = do_fp_load(rd, do_lfs, ea, 4, regs);
			goto ldst_done;

		case 599:	/* lfdx */
		case 631:	/* lfdux */
			if (!(regs->msr & MSR_FP))
				break;
			ea = xform_ea(instr, regs, u);
			err = do_fp_load(rd, do_lfd, ea, 8, regs);
			goto ldst_done;

		case 663:	/* stfsx */
		case 695:	/* stfsux */
			if (!(regs->msr & MSR_FP))
				break;
			ea = xform_ea(instr, regs, u);
			err = do_fp_store(rd, do_stfs, ea, 4, regs);
			goto ldst_done;

		case 727:	/* stfdx */
		case 759:	/* stfdux */
			if (!(regs->msr & MSR_FP))
				break;
			ea = xform_ea(instr, regs, u);
			err = do_fp_store(rd, do_stfd, ea, 8, regs);
			goto ldst_done;
#endif

#ifdef __powerpc64__
		case 660:	/* stdbrx */
			val = byterev_8(regs->gpr[rd]);
			err = write_mem(val, xform_ea(instr, regs, 0), 8, regs);
			goto ldst_done;

#endif
		case 662:	/* stwbrx */
			val = byterev_4(regs->gpr[rd]);
			err = write_mem(val, xform_ea(instr, regs, 0), 4, regs);
			goto ldst_done;

		case 790:	/* lhbrx */
			err = read_mem(&val, xform_ea(instr, regs, 0), 2, regs);
			if (!err)
				regs->gpr[rd] = byterev_2(val);
			goto ldst_done;

		case 918:	/* sthbrx */
			val = byterev_2(regs->gpr[rd]);
			err = write_mem(val, xform_ea(instr, regs, 0), 2, regs);
			goto ldst_done;

#ifdef CONFIG_VSX
		case 844:	/* lxvd2x */
		case 876:	/* lxvd2ux */
			if (!(regs->msr & MSR_VSX))
				break;
			rd |= (instr & 1) << 5;
			ea = xform_ea(instr, regs, u);
			err = do_vsx_load(rd, do_lxvd2x, ea, regs);
			goto ldst_done;

		case 972:	/* stxvd2x */
		case 1004:	/* stxvd2ux */
			if (!(regs->msr & MSR_VSX))
				break;
			rd |= (instr & 1) << 5;
			ea = xform_ea(instr, regs, u);
			err = do_vsx_store(rd, do_stxvd2x, ea, regs);
			goto ldst_done;

#endif /* CONFIG_VSX */
		}
		break;

	case 32:	/* lwz */
	case 33:	/* lwzu */
		err = read_mem(&regs->gpr[rd], dform_ea(instr, regs), 4, regs);
		goto ldst_done;

	case 34:	/* lbz */
	case 35:	/* lbzu */
		err = read_mem(&regs->gpr[rd], dform_ea(instr, regs), 1, regs);
		goto ldst_done;

	case 36:	/* stw */
		val = regs->gpr[rd];
		err = write_mem(val, dform_ea(instr, regs), 4, regs);
		goto ldst_done;

	case 37:	/* stwu */
		val = regs->gpr[rd];
		val3 = dform_ea(instr, regs);
		/*
		 * For PPC32 we always use stwu to change stack point with r1. So
		 * this emulated store may corrupt the exception frame, now we
		 * have to provide the exception frame trampoline, which is pushed
		 * below the kprobed function stack. So we only update gpr[1] but
		 * don't emulate the real store operation. We will do real store
		 * operation safely in exception return code by checking this flag.
		 */
		if ((ra == 1) && !(regs->msr & MSR_PR) \
			&& (val3 >= (regs->gpr[1] - STACK_INT_FRAME_SIZE))) {
#ifdef CONFIG_PPC32
			/*
			 * Check if we will touch kernel sack overflow
			 */
			if (val3 - STACK_INT_FRAME_SIZE <= current->thread.ksp_limit) {
				printk(KERN_CRIT "Can't kprobe this since Kernel stack overflow.\n");
				err = -EINVAL;
				break;
			}
#endif /* CONFIG_PPC32 */
			/*
			 * Check if we already set since that means we'll
			 * lose the previous value.
			 */
			WARN_ON(test_thread_flag(TIF_EMULATE_STACK_STORE));
			set_thread_flag(TIF_EMULATE_STACK_STORE);
			err = 0;
		} else
			err = write_mem(val, val3, 4, regs);
		goto ldst_done;

	case 38:	/* stb */
	case 39:	/* stbu */
		val = regs->gpr[rd];
		err = write_mem(val, dform_ea(instr, regs), 1, regs);
		goto ldst_done;

	case 40:	/* lhz */
	case 41:	/* lhzu */
		err = read_mem(&regs->gpr[rd], dform_ea(instr, regs), 2, regs);
		goto ldst_done;

	case 42:	/* lha */
	case 43:	/* lhau */
		err = read_mem(&regs->gpr[rd], dform_ea(instr, regs), 2, regs);
		if (!err)
			regs->gpr[rd] = (signed short) regs->gpr[rd];
		goto ldst_done;

	case 44:	/* sth */
	case 45:	/* sthu */
		val = regs->gpr[rd];
		err = write_mem(val, dform_ea(instr, regs), 2, regs);
		goto ldst_done;

	case 46:	/* lmw */
		ra = (instr >> 16) & 0x1f;
		if (ra >= rd)
			break;		/* invalid form, ra in range to load */
		ea = dform_ea(instr, regs);
		do {
			err = read_mem(&regs->gpr[rd], ea, 4, regs);
			if (err)
				return 0;
			ea += 4;
		} while (++rd < 32);
		goto instr_done;

	case 47:	/* stmw */
		ea = dform_ea(instr, regs);
		do {
			err = write_mem(regs->gpr[rd], ea, 4, regs);
			if (err)
				return 0;
			ea += 4;
		} while (++rd < 32);
		goto instr_done;

#ifdef CONFIG_PPC_FPU
	case 48:	/* lfs */
	case 49:	/* lfsu */
		if (!(regs->msr & MSR_FP))
			break;
		ea = dform_ea(instr, regs);
		err = do_fp_load(rd, do_lfs, ea, 4, regs);
		goto ldst_done;

	case 50:	/* lfd */
	case 51:	/* lfdu */
		if (!(regs->msr & MSR_FP))
			break;
		ea = dform_ea(instr, regs);
		err = do_fp_load(rd, do_lfd, ea, 8, regs);
		goto ldst_done;

	case 52:	/* stfs */
	case 53:	/* stfsu */
		if (!(regs->msr & MSR_FP))
			break;
		ea = dform_ea(instr, regs);
		err = do_fp_store(rd, do_stfs, ea, 4, regs);
		goto ldst_done;

	case 54:	/* stfd */
	case 55:	/* stfdu */
		if (!(regs->msr & MSR_FP))
			break;
		ea = dform_ea(instr, regs);
		err = do_fp_store(rd, do_stfd, ea, 8, regs);
		goto ldst_done;
#endif

#ifdef __powerpc64__
	case 58:	/* ld[u], lwa */
		switch (instr & 3) {
		case 0:		/* ld */
			err = read_mem(&regs->gpr[rd], dsform_ea(instr, regs),
				       8, regs);
			goto ldst_done;
		case 1:		/* ldu */
			err = read_mem(&regs->gpr[rd], dsform_ea(instr, regs),
				       8, regs);
			goto ldst_done;
		case 2:		/* lwa */
			err = read_mem(&regs->gpr[rd], dsform_ea(instr, regs),
				       4, regs);
			if (!err)
				regs->gpr[rd] = (signed int) regs->gpr[rd];
			goto ldst_done;
		}
		break;

	case 62:	/* std[u] */
		val = regs->gpr[rd];
		switch (instr & 3) {
		case 0:		/* std */
			err = write_mem(val, dsform_ea(instr, regs), 8, regs);
			goto ldst_done;
		case 1:		/* stdu */
			err = write_mem(val, dsform_ea(instr, regs), 8, regs);
			goto ldst_done;
		}
		break;
#endif /* __powerpc64__ */

	}
	err = -EINVAL;

 ldst_done:
	if (err) {
		regs->gpr[ra] = old_ra;
		return 0;	/* invoke DSI if -EFAULT? */
	}
 instr_done:
	regs->nip = truncate_if_32bit(regs->msr, regs->nip + 4);
	return 1;

 logical_done:
	if (instr & 1)
		set_cr0(regs, ra);
	goto instr_done;

 arith_done:
	if (instr & 1)
		set_cr0(regs, rd);
	goto instr_done;
}
OpenPOWER on IntegriCloud