summaryrefslogtreecommitdiffstats
path: root/arch/arm64/kvm/guest.c
blob: cf4c495a4321332b7bc5a1979fc84d3084da355e (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
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2012,2013 - ARM Ltd
 * Author: Marc Zyngier <marc.zyngier@arm.com>
 *
 * Derived from arch/arm/kvm/guest.c:
 * Copyright (C) 2012 - Virtual Open Systems and Columbia University
 * Author: Christoffer Dall <c.dall@virtualopensystems.com>
 */

#include <linux/bits.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/nospec.h>
#include <linux/kvm_host.h>
#include <linux/module.h>
#include <linux/stddef.h>
#include <linux/string.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>
#include <kvm/arm_hypercalls.h>
#include <asm/cputype.h>
#include <linux/uaccess.h>
#include <asm/fpsimd.h>
#include <asm/kvm.h>
#include <asm/kvm_emulate.h>
#include <asm/sigcontext.h>

#include "trace.h"

const struct _kvm_stats_desc kvm_vm_stats_desc[] = {
	KVM_GENERIC_VM_STATS()
};

const struct kvm_stats_header kvm_vm_stats_header = {
	.name_size = KVM_STATS_NAME_SIZE,
	.num_desc = ARRAY_SIZE(kvm_vm_stats_desc),
	.id_offset =  sizeof(struct kvm_stats_header),
	.desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE,
	.data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE +
		       sizeof(kvm_vm_stats_desc),
};

const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = {
	KVM_GENERIC_VCPU_STATS(),
	STATS_DESC_COUNTER(VCPU, hvc_exit_stat),
	STATS_DESC_COUNTER(VCPU, wfe_exit_stat),
	STATS_DESC_COUNTER(VCPU, wfi_exit_stat),
	STATS_DESC_COUNTER(VCPU, mmio_exit_user),
	STATS_DESC_COUNTER(VCPU, mmio_exit_kernel),
	STATS_DESC_COUNTER(VCPU, signal_exits),
	STATS_DESC_COUNTER(VCPU, exits)
};

const struct kvm_stats_header kvm_vcpu_stats_header = {
	.name_size = KVM_STATS_NAME_SIZE,
	.num_desc = ARRAY_SIZE(kvm_vcpu_stats_desc),
	.id_offset = sizeof(struct kvm_stats_header),
	.desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE,
	.data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE +
		       sizeof(kvm_vcpu_stats_desc),
};

static bool core_reg_offset_is_vreg(u64 off)
{
	return off >= KVM_REG_ARM_CORE_REG(fp_regs.vregs) &&
		off < KVM_REG_ARM_CORE_REG(fp_regs.fpsr);
}

static u64 core_reg_offset_from_id(u64 id)
{
	return id & ~(KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK | KVM_REG_ARM_CORE);
}

static int core_reg_size_from_offset(const struct kvm_vcpu *vcpu, u64 off)
{
	int size;

	switch (off) {
	case KVM_REG_ARM_CORE_REG(regs.regs[0]) ...
	     KVM_REG_ARM_CORE_REG(regs.regs[30]):
	case KVM_REG_ARM_CORE_REG(regs.sp):
	case KVM_REG_ARM_CORE_REG(regs.pc):
	case KVM_REG_ARM_CORE_REG(regs.pstate):
	case KVM_REG_ARM_CORE_REG(sp_el1):
	case KVM_REG_ARM_CORE_REG(elr_el1):
	case KVM_REG_ARM_CORE_REG(spsr[0]) ...
	     KVM_REG_ARM_CORE_REG(spsr[KVM_NR_SPSR - 1]):
		size = sizeof(__u64);
		break;

	case KVM_REG_ARM_CORE_REG(fp_regs.vregs[0]) ...
	     KVM_REG_ARM_CORE_REG(fp_regs.vregs[31]):
		size = sizeof(__uint128_t);
		break;

	case KVM_REG_ARM_CORE_REG(fp_regs.fpsr):
	case KVM_REG_ARM_CORE_REG(fp_regs.fpcr):
		size = sizeof(__u32);
		break;

	default:
		return -EINVAL;
	}

	if (!IS_ALIGNED(off, size / sizeof(__u32)))
		return -EINVAL;

	/*
	 * The KVM_REG_ARM64_SVE regs must be used instead of
	 * KVM_REG_ARM_CORE for accessing the FPSIMD V-registers on
	 * SVE-enabled vcpus:
	 */
	if (vcpu_has_sve(vcpu) && core_reg_offset_is_vreg(off))
		return -EINVAL;

	return size;
}

static void *core_reg_addr(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
	u64 off = core_reg_offset_from_id(reg->id);
	int size = core_reg_size_from_offset(vcpu, off);

	if (size < 0)
		return NULL;

	if (KVM_REG_SIZE(reg->id) != size)
		return NULL;

	switch (off) {
	case KVM_REG_ARM_CORE_REG(regs.regs[0]) ...
	     KVM_REG_ARM_CORE_REG(regs.regs[30]):
		off -= KVM_REG_ARM_CORE_REG(regs.regs[0]);
		off /= 2;
		return &vcpu->arch.ctxt.regs.regs[off];

	case KVM_REG_ARM_CORE_REG(regs.sp):
		return &vcpu->arch.ctxt.regs.sp;

	case KVM_REG_ARM_CORE_REG(regs.pc):
		return &vcpu->arch.ctxt.regs.pc;

	case KVM_REG_ARM_CORE_REG(regs.pstate):
		return &vcpu->arch.ctxt.regs.pstate;

	case KVM_REG_ARM_CORE_REG(sp_el1):
		return __ctxt_sys_reg(&vcpu->arch.ctxt, SP_EL1);

	case KVM_REG_ARM_CORE_REG(elr_el1):
		return __ctxt_sys_reg(&vcpu->arch.ctxt, ELR_EL1);

	case KVM_REG_ARM_CORE_REG(spsr[KVM_SPSR_EL1]):
		return __ctxt_sys_reg(&vcpu->arch.ctxt, SPSR_EL1);

	case KVM_REG_ARM_CORE_REG(spsr[KVM_SPSR_ABT]):
		return &vcpu->arch.ctxt.spsr_abt;

	case KVM_REG_ARM_CORE_REG(spsr[KVM_SPSR_UND]):
		return &vcpu->arch.ctxt.spsr_und;

	case KVM_REG_ARM_CORE_REG(spsr[KVM_SPSR_IRQ]):
		return &vcpu->arch.ctxt.spsr_irq;

	case KVM_REG_ARM_CORE_REG(spsr[KVM_SPSR_FIQ]):
		return &vcpu->arch.ctxt.spsr_fiq;

	case KVM_REG_ARM_CORE_REG(fp_regs.vregs[0]) ...
	     KVM_REG_ARM_CORE_REG(fp_regs.vregs[31]):
		off -= KVM_REG_ARM_CORE_REG(fp_regs.vregs[0]);
		off /= 4;
		return &vcpu->arch.ctxt.fp_regs.vregs[off];

	case KVM_REG_ARM_CORE_REG(fp_regs.fpsr):
		return &vcpu->arch.ctxt.fp_regs.fpsr;

	case KVM_REG_ARM_CORE_REG(fp_regs.fpcr):
		return &vcpu->arch.ctxt.fp_regs.fpcr;

	default:
		return NULL;
	}
}

static int get_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
	/*
	 * Because the kvm_regs structure is a mix of 32, 64 and
	 * 128bit fields, we index it as if it was a 32bit
	 * array. Hence below, nr_regs is the number of entries, and
	 * off the index in the "array".
	 */
	__u32 __user *uaddr = (__u32 __user *)(unsigned long)reg->addr;
	int nr_regs = sizeof(struct kvm_regs) / sizeof(__u32);
	void *addr;
	u32 off;

	/* Our ID is an index into the kvm_regs struct. */
	off = core_reg_offset_from_id(reg->id);
	if (off >= nr_regs ||
	    (off + (KVM_REG_SIZE(reg->id) / sizeof(__u32))) >= nr_regs)
		return -ENOENT;

	addr = core_reg_addr(vcpu, reg);
	if (!addr)
		return -EINVAL;

	if (copy_to_user(uaddr, addr, KVM_REG_SIZE(reg->id)))
		return -EFAULT;

	return 0;
}

static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
	__u32 __user *uaddr = (__u32 __user *)(unsigned long)reg->addr;
	int nr_regs = sizeof(struct kvm_regs) / sizeof(__u32);
	__uint128_t tmp;
	void *valp = &tmp, *addr;
	u64 off;
	int err = 0;

	/* Our ID is an index into the kvm_regs struct. */
	off = core_reg_offset_from_id(reg->id);
	if (off >= nr_regs ||
	    (off + (KVM_REG_SIZE(reg->id) / sizeof(__u32))) >= nr_regs)
		return -ENOENT;

	addr = core_reg_addr(vcpu, reg);
	if (!addr)
		return -EINVAL;

	if (KVM_REG_SIZE(reg->id) > sizeof(tmp))
		return -EINVAL;

	if (copy_from_user(valp, uaddr, KVM_REG_SIZE(reg->id))) {
		err = -EFAULT;
		goto out;
	}

	if (off == KVM_REG_ARM_CORE_REG(regs.pstate)) {
		u64 mode = (*(u64 *)valp) & PSR_AA32_MODE_MASK;
		switch (mode) {
		case PSR_AA32_MODE_USR:
			if (!kvm_supports_32bit_el0())
				return -EINVAL;
			break;
		case PSR_AA32_MODE_FIQ:
		case PSR_AA32_MODE_IRQ:
		case PSR_AA32_MODE_SVC:
		case PSR_AA32_MODE_ABT:
		case PSR_AA32_MODE_UND:
			if (!vcpu_el1_is_32bit(vcpu))
				return -EINVAL;
			break;
		case PSR_MODE_EL0t:
		case PSR_MODE_EL1t:
		case PSR_MODE_EL1h:
			if (vcpu_el1_is_32bit(vcpu))
				return -EINVAL;
			break;
		default:
			err = -EINVAL;
			goto out;
		}
	}

	memcpy(addr, valp, KVM_REG_SIZE(reg->id));

	if (*vcpu_cpsr(vcpu) & PSR_MODE32_BIT) {
		int i, nr_reg;

		switch (*vcpu_cpsr(vcpu)) {
		/*
		 * Either we are dealing with user mode, and only the
		 * first 15 registers (+ PC) must be narrowed to 32bit.
		 * AArch32 r0-r14 conveniently map to AArch64 x0-x14.
		 */
		case PSR_AA32_MODE_USR:
		case PSR_AA32_MODE_SYS:
			nr_reg = 15;
			break;

		/*
		 * Otherwise, this is a privileged mode, and *all* the
		 * registers must be narrowed to 32bit.
		 */
		default:
			nr_reg = 31;
			break;
		}

		for (i = 0; i < nr_reg; i++)
			vcpu_set_reg(vcpu, i, (u32)vcpu_get_reg(vcpu, i));

		*vcpu_pc(vcpu) = (u32)*vcpu_pc(vcpu);
	}
out:
	return err;
}

#define vq_word(vq) (((vq) - SVE_VQ_MIN) / 64)
#define vq_mask(vq) ((u64)1 << ((vq) - SVE_VQ_MIN) % 64)
#define vq_present(vqs, vq) (!!((vqs)[vq_word(vq)] & vq_mask(vq)))

static int get_sve_vls(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
	unsigned int max_vq, vq;
	u64 vqs[KVM_ARM64_SVE_VLS_WORDS];

	if (!vcpu_has_sve(vcpu))
		return -ENOENT;

	if (WARN_ON(!sve_vl_valid(vcpu->arch.sve_max_vl)))
		return -EINVAL;

	memset(vqs, 0, sizeof(vqs));

	max_vq = vcpu_sve_max_vq(vcpu);
	for (vq = SVE_VQ_MIN; vq <= max_vq; ++vq)
		if (sve_vq_available(vq))
			vqs[vq_word(vq)] |= vq_mask(vq);

	if (copy_to_user((void __user *)reg->addr, vqs, sizeof(vqs)))
		return -EFAULT;

	return 0;
}

static int set_sve_vls(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
	unsigned int max_vq, vq;
	u64 vqs[KVM_ARM64_SVE_VLS_WORDS];

	if (!vcpu_has_sve(vcpu))
		return -ENOENT;

	if (kvm_arm_vcpu_sve_finalized(vcpu))
		return -EPERM; /* too late! */

	if (WARN_ON(vcpu->arch.sve_state))
		return -EINVAL;

	if (copy_from_user(vqs, (const void __user *)reg->addr, sizeof(vqs)))
		return -EFAULT;

	max_vq = 0;
	for (vq = SVE_VQ_MIN; vq <= SVE_VQ_MAX; ++vq)
		if (vq_present(vqs, vq))
			max_vq = vq;

	if (max_vq > sve_vq_from_vl(kvm_sve_max_vl))
		return -EINVAL;

	/*
	 * Vector lengths supported by the host can't currently be
	 * hidden from the guest individually: instead we can only set a
	 * maximum via ZCR_EL2.LEN.  So, make sure the available vector
	 * lengths match the set requested exactly up to the requested
	 * maximum:
	 */
	for (vq = SVE_VQ_MIN; vq <= max_vq; ++vq)
		if (vq_present(vqs, vq) != sve_vq_available(vq))
			return -EINVAL;

	/* Can't run with no vector lengths at all: */
	if (max_vq < SVE_VQ_MIN)
		return -EINVAL;

	/* vcpu->arch.sve_state will be alloc'd by kvm_vcpu_finalize_sve() */
	vcpu->arch.sve_max_vl = sve_vl_from_vq(max_vq);

	return 0;
}

#define SVE_REG_SLICE_SHIFT	0
#define SVE_REG_SLICE_BITS	5
#define SVE_REG_ID_SHIFT	(SVE_REG_SLICE_SHIFT + SVE_REG_SLICE_BITS)
#define SVE_REG_ID_BITS		5

#define SVE_REG_SLICE_MASK					\
	GENMASK(SVE_REG_SLICE_SHIFT + SVE_REG_SLICE_BITS - 1,	\
		SVE_REG_SLICE_SHIFT)
#define SVE_REG_ID_MASK							\
	GENMASK(SVE_REG_ID_SHIFT + SVE_REG_ID_BITS - 1, SVE_REG_ID_SHIFT)

#define SVE_NUM_SLICES (1 << SVE_REG_SLICE_BITS)

#define KVM_SVE_ZREG_SIZE KVM_REG_SIZE(KVM_REG_ARM64_SVE_ZREG(0, 0))
#define KVM_SVE_PREG_SIZE KVM_REG_SIZE(KVM_REG_ARM64_SVE_PREG(0, 0))

/*
 * Number of register slices required to cover each whole SVE register.
 * NOTE: Only the first slice every exists, for now.
 * If you are tempted to modify this, you must also rework sve_reg_to_region()
 * to match:
 */
#define vcpu_sve_slices(vcpu) 1

/* Bounds of a single SVE register slice within vcpu->arch.sve_state */
struct sve_state_reg_region {
	unsigned int koffset;	/* offset into sve_state in kernel memory */
	unsigned int klen;	/* length in kernel memory */
	unsigned int upad;	/* extra trailing padding in user memory */
};

/*
 * Validate SVE register ID and get sanitised bounds for user/kernel SVE
 * register copy
 */
static int sve_reg_to_region(struct sve_state_reg_region *region,
			     struct kvm_vcpu *vcpu,
			     const struct kvm_one_reg *reg)
{
	/* reg ID ranges for Z- registers */
	const u64 zreg_id_min = KVM_REG_ARM64_SVE_ZREG(0, 0);
	const u64 zreg_id_max = KVM_REG_ARM64_SVE_ZREG(SVE_NUM_ZREGS - 1,
						       SVE_NUM_SLICES - 1);

	/* reg ID ranges for P- registers and FFR (which are contiguous) */
	const u64 preg_id_min = KVM_REG_ARM64_SVE_PREG(0, 0);
	const u64 preg_id_max = KVM_REG_ARM64_SVE_FFR(SVE_NUM_SLICES - 1);

	unsigned int vq;
	unsigned int reg_num;

	unsigned int reqoffset, reqlen; /* User-requested offset and length */
	unsigned int maxlen; /* Maximum permitted length */

	size_t sve_state_size;

	const u64 last_preg_id = KVM_REG_ARM64_SVE_PREG(SVE_NUM_PREGS - 1,
							SVE_NUM_SLICES - 1);

	/* Verify that the P-regs and FFR really do have contiguous IDs: */
	BUILD_BUG_ON(KVM_REG_ARM64_SVE_FFR(0) != last_preg_id + 1);

	/* Verify that we match the UAPI header: */
	BUILD_BUG_ON(SVE_NUM_SLICES != KVM_ARM64_SVE_MAX_SLICES);

	reg_num = (reg->id & SVE_REG_ID_MASK) >> SVE_REG_ID_SHIFT;

	if (reg->id >= zreg_id_min && reg->id <= zreg_id_max) {
		if (!vcpu_has_sve(vcpu) || (reg->id & SVE_REG_SLICE_MASK) > 0)
			return -ENOENT;

		vq = vcpu_sve_max_vq(vcpu);

		reqoffset = SVE_SIG_ZREG_OFFSET(vq, reg_num) -
				SVE_SIG_REGS_OFFSET;
		reqlen = KVM_SVE_ZREG_SIZE;
		maxlen = SVE_SIG_ZREG_SIZE(vq);
	} else if (reg->id >= preg_id_min && reg->id <= preg_id_max) {
		if (!vcpu_has_sve(vcpu) || (reg->id & SVE_REG_SLICE_MASK) > 0)
			return -ENOENT;

		vq = vcpu_sve_max_vq(vcpu);

		reqoffset = SVE_SIG_PREG_OFFSET(vq, reg_num) -
				SVE_SIG_REGS_OFFSET;
		reqlen = KVM_SVE_PREG_SIZE;
		maxlen = SVE_SIG_PREG_SIZE(vq);
	} else {
		return -EINVAL;
	}

	sve_state_size = vcpu_sve_state_size(vcpu);
	if (WARN_ON(!sve_state_size))
		return -EINVAL;

	region->koffset = array_index_nospec(reqoffset, sve_state_size);
	region->klen = min(maxlen, reqlen);
	region->upad = reqlen - region->klen;

	return 0;
}

static int get_sve_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
	int ret;
	struct sve_state_reg_region region;
	char __user *uptr = (char __user *)reg->addr;

	/* Handle the KVM_REG_ARM64_SVE_VLS pseudo-reg as a special case: */
	if (reg->id == KVM_REG_ARM64_SVE_VLS)
		return get_sve_vls(vcpu, reg);

	/* Try to interpret reg ID as an architectural SVE register... */
	ret = sve_reg_to_region(&region, vcpu, reg);
	if (ret)
		return ret;

	if (!kvm_arm_vcpu_sve_finalized(vcpu))
		return -EPERM;

	if (copy_to_user(uptr, vcpu->arch.sve_state + region.koffset,
			 region.klen) ||
	    clear_user(uptr + region.klen, region.upad))
		return -EFAULT;

	return 0;
}

static int set_sve_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
	int ret;
	struct sve_state_reg_region region;
	const char __user *uptr = (const char __user *)reg->addr;

	/* Handle the KVM_REG_ARM64_SVE_VLS pseudo-reg as a special case: */
	if (reg->id == KVM_REG_ARM64_SVE_VLS)
		return set_sve_vls(vcpu, reg);

	/* Try to interpret reg ID as an architectural SVE register... */
	ret = sve_reg_to_region(&region, vcpu, reg);
	if (ret)
		return ret;

	if (!kvm_arm_vcpu_sve_finalized(vcpu))
		return -EPERM;

	if (copy_from_user(vcpu->arch.sve_state + region.koffset, uptr,
			   region.klen))
		return -EFAULT;

	return 0;
}

int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
{
	return -EINVAL;
}

int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
{
	return -EINVAL;
}

static int copy_core_reg_indices(const struct kvm_vcpu *vcpu,
				 u64 __user *uindices)
{
	unsigned int i;
	int n = 0;

	for (i = 0; i < sizeof(struct kvm_regs) / sizeof(__u32); i++) {
		u64 reg = KVM_REG_ARM64 | KVM_REG_ARM_CORE | i;
		int size = core_reg_size_from_offset(vcpu, i);

		if (size < 0)
			continue;

		switch (size) {
		case sizeof(__u32):
			reg |= KVM_REG_SIZE_U32;
			break;

		case sizeof(__u64):
			reg |= KVM_REG_SIZE_U64;
			break;

		case sizeof(__uint128_t):
			reg |= KVM_REG_SIZE_U128;
			break;

		default:
			WARN_ON(1);
			continue;
		}

		if (uindices) {
			if (put_user(reg, uindices))
				return -EFAULT;
			uindices++;
		}

		n++;
	}

	return n;
}

static unsigned long num_core_regs(const struct kvm_vcpu *vcpu)
{
	return copy_core_reg_indices(vcpu, NULL);
}

/**
 * ARM64 versions of the TIMER registers, always available on arm64
 */

#define NUM_TIMER_REGS 3

static bool is_timer_reg(u64 index)
{
	switch (index) {
	case KVM_REG_ARM_TIMER_CTL:
	case KVM_REG_ARM_TIMER_CNT:
	case KVM_REG_ARM_TIMER_CVAL:
		return true;
	}
	return false;
}

static int copy_timer_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
{
	if (put_user(KVM_REG_ARM_TIMER_CTL, uindices))
		return -EFAULT;
	uindices++;
	if (put_user(KVM_REG_ARM_TIMER_CNT, uindices))
		return -EFAULT;
	uindices++;
	if (put_user(KVM_REG_ARM_TIMER_CVAL, uindices))
		return -EFAULT;

	return 0;
}

static int set_timer_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
	void __user *uaddr = (void __user *)(long)reg->addr;
	u64 val;
	int ret;

	ret = copy_from_user(&val, uaddr, KVM_REG_SIZE(reg->id));
	if (ret != 0)
		return -EFAULT;

	return kvm_arm_timer_set_reg(vcpu, reg->id, val);
}

static int get_timer_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
	void __user *uaddr = (void __user *)(long)reg->addr;
	u64 val;

	val = kvm_arm_timer_get_reg(vcpu, reg->id);
	return copy_to_user(uaddr, &val, KVM_REG_SIZE(reg->id)) ? -EFAULT : 0;
}

static unsigned long num_sve_regs(const struct kvm_vcpu *vcpu)
{
	const unsigned int slices = vcpu_sve_slices(vcpu);

	if (!vcpu_has_sve(vcpu))
		return 0;

	/* Policed by KVM_GET_REG_LIST: */
	WARN_ON(!kvm_arm_vcpu_sve_finalized(vcpu));

	return slices * (SVE_NUM_PREGS + SVE_NUM_ZREGS + 1 /* FFR */)
		+ 1; /* KVM_REG_ARM64_SVE_VLS */
}

static int copy_sve_reg_indices(const struct kvm_vcpu *vcpu,
				u64 __user *uindices)
{
	const unsigned int slices = vcpu_sve_slices(vcpu);
	u64 reg;
	unsigned int i, n;
	int num_regs = 0;

	if (!vcpu_has_sve(vcpu))
		return 0;

	/* Policed by KVM_GET_REG_LIST: */
	WARN_ON(!kvm_arm_vcpu_sve_finalized(vcpu));

	/*
	 * Enumerate this first, so that userspace can save/restore in
	 * the order reported by KVM_GET_REG_LIST:
	 */
	reg = KVM_REG_ARM64_SVE_VLS;
	if (put_user(reg, uindices++))
		return -EFAULT;
	++num_regs;

	for (i = 0; i < slices; i++) {
		for (n = 0; n < SVE_NUM_ZREGS; n++) {
			reg = KVM_REG_ARM64_SVE_ZREG(n, i);
			if (put_user(reg, uindices++))
				return -EFAULT;
			num_regs++;
		}

		for (n = 0; n < SVE_NUM_PREGS; n++) {
			reg = KVM_REG_ARM64_SVE_PREG(n, i);
			if (put_user(reg, uindices++))
				return -EFAULT;
			num_regs++;
		}

		reg = KVM_REG_ARM64_SVE_FFR(i);
		if (put_user(reg, uindices++))
			return -EFAULT;
		num_regs++;
	}

	return num_regs;
}

/**
 * kvm_arm_num_regs - how many registers do we present via KVM_GET_ONE_REG
 *
 * This is for all registers.
 */
unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu)
{
	unsigned long res = 0;

	res += num_core_regs(vcpu);
	res += num_sve_regs(vcpu);
	res += kvm_arm_num_sys_reg_descs(vcpu);
	res += kvm_arm_get_fw_num_regs(vcpu);
	res += NUM_TIMER_REGS;

	return res;
}

/**
 * kvm_arm_copy_reg_indices - get indices of all registers.
 *
 * We do core registers right here, then we append system regs.
 */
int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
{
	int ret;

	ret = copy_core_reg_indices(vcpu, uindices);
	if (ret < 0)
		return ret;
	uindices += ret;

	ret = copy_sve_reg_indices(vcpu, uindices);
	if (ret < 0)
		return ret;
	uindices += ret;

	ret = kvm_arm_copy_fw_reg_indices(vcpu, uindices);
	if (ret < 0)
		return ret;
	uindices += kvm_arm_get_fw_num_regs(vcpu);

	ret = copy_timer_indices(vcpu, uindices);
	if (ret < 0)
		return ret;
	uindices += NUM_TIMER_REGS;

	return kvm_arm_copy_sys_reg_indices(vcpu, uindices);
}

int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
	/* We currently use nothing arch-specific in upper 32 bits */
	if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM64 >> 32)
		return -EINVAL;

	switch (reg->id & KVM_REG_ARM_COPROC_MASK) {
	case KVM_REG_ARM_CORE:	return get_core_reg(vcpu, reg);
	case KVM_REG_ARM_FW:
	case KVM_REG_ARM_FW_FEAT_BMAP:
		return kvm_arm_get_fw_reg(vcpu, reg);
	case KVM_REG_ARM64_SVE:	return get_sve_reg(vcpu, reg);
	}

	if (is_timer_reg(reg->id))
		return get_timer_reg(vcpu, reg);

	return kvm_arm_sys_reg_get_reg(vcpu, reg);
}

int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
	/* We currently use nothing arch-specific in upper 32 bits */
	if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM64 >> 32)
		return -EINVAL;

	switch (reg->id & KVM_REG_ARM_COPROC_MASK) {
	case KVM_REG_ARM_CORE:	return set_core_reg(vcpu, reg);
	case KVM_REG_ARM_FW:
	case KVM_REG_ARM_FW_FEAT_BMAP:
		return kvm_arm_set_fw_reg(vcpu, reg);
	case KVM_REG_ARM64_SVE:	return set_sve_reg(vcpu, reg);
	}

	if (is_timer_reg(reg->id))
		return set_timer_reg(vcpu, reg);

	return kvm_arm_sys_reg_set_reg(vcpu, reg);
}

int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
				  struct kvm_sregs *sregs)
{
	return -EINVAL;
}

int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
				  struct kvm_sregs *sregs)
{
	return -EINVAL;
}

int __kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
			      struct kvm_vcpu_events *events)
{
	events->exception.serror_pending = !!(vcpu->arch.hcr_el2 & HCR_VSE);
	events->exception.serror_has_esr = cpus_have_const_cap(ARM64_HAS_RAS_EXTN);

	if (events->exception.serror_pending && events->exception.serror_has_esr)
		events->exception.serror_esr = vcpu_get_vsesr(vcpu);

	/*
	 * We never return a pending ext_dabt here because we deliver it to
	 * the virtual CPU directly when setting the event and it's no longer
	 * 'pending' at this point.
	 */

	return 0;
}

int __kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
			      struct kvm_vcpu_events *events)
{
	bool serror_pending = events->exception.serror_pending;
	bool has_esr = events->exception.serror_has_esr;
	bool ext_dabt_pending = events->exception.ext_dabt_pending;

	if (serror_pending && has_esr) {
		if (!cpus_have_const_cap(ARM64_HAS_RAS_EXTN))
			return -EINVAL;

		if (!((events->exception.serror_esr) & ~ESR_ELx_ISS_MASK))
			kvm_set_sei_esr(vcpu, events->exception.serror_esr);
		else
			return -EINVAL;
	} else if (serror_pending) {
		kvm_inject_vabt(vcpu);
	}

	if (ext_dabt_pending)
		kvm_inject_dabt(vcpu, kvm_vcpu_get_hfar(vcpu));

	return 0;
}

u32 __attribute_const__ kvm_target_cpu(void)
{
	unsigned long implementor = read_cpuid_implementor();
	unsigned long part_number = read_cpuid_part_number();

	switch (implementor) {
	case ARM_CPU_IMP_ARM:
		switch (part_number) {
		case ARM_CPU_PART_AEM_V8:
			return KVM_ARM_TARGET_AEM_V8;
		case ARM_CPU_PART_FOUNDATION:
			return KVM_ARM_TARGET_FOUNDATION_V8;
		case ARM_CPU_PART_CORTEX_A53:
			return KVM_ARM_TARGET_CORTEX_A53;
		case ARM_CPU_PART_CORTEX_A57:
			return KVM_ARM_TARGET_CORTEX_A57;
		}
		break;
	case ARM_CPU_IMP_APM:
		switch (part_number) {
		case APM_CPU_PART_POTENZA:
			return KVM_ARM_TARGET_XGENE_POTENZA;
		}
		break;
	}

	/* Return a default generic target */
	return KVM_ARM_TARGET_GENERIC_V8;
}

void kvm_vcpu_preferred_target(struct kvm_vcpu_init *init)
{
	u32 target = kvm_target_cpu();

	memset(init, 0, sizeof(*init));

	/*
	 * For now, we don't return any features.
	 * In future, we might use features to return target
	 * specific features available for the preferred
	 * target type.
	 */
	init->target = (__u32)target;
}

int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
{
	return -EINVAL;
}

int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
{
	return -EINVAL;
}

int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
				  struct kvm_translation *tr)
{
	return -EINVAL;
}

/**
 * kvm_arch_vcpu_ioctl_set_guest_debug - set up guest debugging
 * @kvm:	pointer to the KVM struct
 * @kvm_guest_debug: the ioctl data buffer
 *
 * This sets up and enables the VM for guest debugging. Userspace
 * passes in a control flag to enable different debug types and
 * potentially other architecture specific information in the rest of
 * the structure.
 */
int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
					struct kvm_guest_debug *dbg)
{
	int ret = 0;

	trace_kvm_set_guest_debug(vcpu, dbg->control);

	if (dbg->control & ~KVM_GUESTDBG_VALID_MASK) {
		ret = -EINVAL;
		goto out;
	}

	if (dbg->control & KVM_GUESTDBG_ENABLE) {
		vcpu->guest_debug = dbg->control;

		/* Hardware assisted Break and Watch points */
		if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW) {
			vcpu->arch.external_debug_state = dbg->arch;
		}

	} else {
		/* If not enabled clear all flags */
		vcpu->guest_debug = 0;
		vcpu_clear_flag(vcpu, DBG_SS_ACTIVE_PENDING);
	}

out:
	return ret;
}

int kvm_arm_vcpu_arch_set_attr(struct kvm_vcpu *vcpu,
			       struct kvm_device_attr *attr)
{
	int ret;

	switch (attr->group) {
	case KVM_ARM_VCPU_PMU_V3_CTRL:
		ret = kvm_arm_pmu_v3_set_attr(vcpu, attr);
		break;
	case KVM_ARM_VCPU_TIMER_CTRL:
		ret = kvm_arm_timer_set_attr(vcpu, attr);
		break;
	case KVM_ARM_VCPU_PVTIME_CTRL:
		ret = kvm_arm_pvtime_set_attr(vcpu, attr);
		break;
	default:
		ret = -ENXIO;
		break;
	}

	return ret;
}

int kvm_arm_vcpu_arch_get_attr(struct kvm_vcpu *vcpu,
			       struct kvm_device_attr *attr)
{
	int ret;

	switch (attr->group) {
	case KVM_ARM_VCPU_PMU_V3_CTRL:
		ret = kvm_arm_pmu_v3_get_attr(vcpu, attr);
		break;
	case KVM_ARM_VCPU_TIMER_CTRL:
		ret = kvm_arm_timer_get_attr(vcpu, attr);
		break;
	case KVM_ARM_VCPU_PVTIME_CTRL:
		ret = kvm_arm_pvtime_get_attr(vcpu, attr);
		break;
	default:
		ret = -ENXIO;
		break;
	}

	return ret;
}

int kvm_arm_vcpu_arch_has_attr(struct kvm_vcpu *vcpu,
			       struct kvm_device_attr *attr)
{
	int ret;

	switch (attr->group) {
	case KVM_ARM_VCPU_PMU_V3_CTRL:
		ret = kvm_arm_pmu_v3_has_attr(vcpu, attr);
		break;
	case KVM_ARM_VCPU_TIMER_CTRL:
		ret = kvm_arm_timer_has_attr(vcpu, attr);
		break;
	case KVM_ARM_VCPU_PVTIME_CTRL:
		ret = kvm_arm_pvtime_has_attr(vcpu, attr);
		break;
	default:
		ret = -ENXIO;
		break;
	}

	return ret;
}

long kvm_vm_ioctl_mte_copy_tags(struct kvm *kvm,
				struct kvm_arm_copy_mte_tags *copy_tags)
{
	gpa_t guest_ipa = copy_tags->guest_ipa;
	size_t length = copy_tags->length;
	void __user *tags = copy_tags->addr;
	gpa_t gfn;
	bool write = !(copy_tags->flags & KVM_ARM_TAGS_FROM_GUEST);
	int ret = 0;

	if (!kvm_has_mte(kvm))
		return -EINVAL;

	if (copy_tags->reserved[0] || copy_tags->reserved[1])
		return -EINVAL;

	if (copy_tags->flags & ~KVM_ARM_TAGS_FROM_GUEST)
		return -EINVAL;

	if (length & ~PAGE_MASK || guest_ipa & ~PAGE_MASK)
		return -EINVAL;

	gfn = gpa_to_gfn(guest_ipa);

	mutex_lock(&kvm->slots_lock);

	while (length > 0) {
		kvm_pfn_t pfn = gfn_to_pfn_prot(kvm, gfn, write, NULL);
		void *maddr;
		unsigned long num_tags;
		struct page *page;

		if (is_error_noslot_pfn(pfn)) {
			ret = -EFAULT;
			goto out;
		}

		page = pfn_to_online_page(pfn);
		if (!page) {
			/* Reject ZONE_DEVICE memory */
			ret = -EFAULT;
			goto out;
		}
		maddr = page_address(page);

		if (!write) {
			if (page_mte_tagged(page))
				num_tags = mte_copy_tags_to_user(tags, maddr,
							MTE_GRANULES_PER_PAGE);
			else
				/* No tags in memory, so write zeros */
				num_tags = MTE_GRANULES_PER_PAGE -
					clear_user(tags, MTE_GRANULES_PER_PAGE);
			kvm_release_pfn_clean(pfn);
		} else {
			/*
			 * Only locking to serialise with a concurrent
			 * set_pte_at() in the VMM but still overriding the
			 * tags, hence ignoring the return value.
			 */
			try_page_mte_tagging(page);
			num_tags = mte_copy_tags_from_user(maddr, tags,
							MTE_GRANULES_PER_PAGE);

			/* uaccess failed, don't leave stale tags */
			if (num_tags != MTE_GRANULES_PER_PAGE)
				mte_clear_page_tags(maddr);
			set_page_mte_tagged(page);

			kvm_release_pfn_dirty(pfn);
		}

		if (num_tags != MTE_GRANULES_PER_PAGE) {
			ret = -EFAULT;
			goto out;
		}

		gfn++;
		tags += num_tags;
		length -= PAGE_SIZE;
	}

out:
	mutex_unlock(&kvm->slots_lock);
	/* If some data has been copied report the number of bytes copied */
	if (length != copy_tags->length)
		return copy_tags->length - length;
	return ret;
}