Free Electrons

Embedded Linux Experts

  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
/*
 * s390host.c --  hosting zSeries kernel virtual machines
 *
 * Copyright IBM Corp. 2008,2009
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License (version 2 only)
 * as published by the Free Software Foundation.
 *
 *    Author(s): Carsten Otte <cotte@de.ibm.com>
 *               Christian Borntraeger <borntraeger@de.ibm.com>
 *               Heiko Carstens <heiko.carstens@de.ibm.com>
 *               Christian Ehrhardt <ehrhardt@de.ibm.com>
 */

#include <linux/compiler.h>
#include <linux/err.h>
#include <linux/fs.h>
#include <linux/hrtimer.h>
#include <linux/init.h>
#include <linux/kvm.h>
#include <linux/kvm_host.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/timer.h>
#include <asm/asm-offsets.h>
#include <asm/lowcore.h>
#include <asm/pgtable.h>
#include <asm/nmi.h>
#include <asm/switch_to.h>
#include "kvm-s390.h"
#include "gaccess.h"

#define VCPU_STAT(x) offsetof(struct kvm_vcpu, stat.x), KVM_STAT_VCPU

struct kvm_stats_debugfs_item debugfs_entries[] = {
	{ "userspace_handled", VCPU_STAT(exit_userspace) },
	{ "exit_null", VCPU_STAT(exit_null) },
	{ "exit_validity", VCPU_STAT(exit_validity) },
	{ "exit_stop_request", VCPU_STAT(exit_stop_request) },
	{ "exit_external_request", VCPU_STAT(exit_external_request) },
	{ "exit_external_interrupt", VCPU_STAT(exit_external_interrupt) },
	{ "exit_instruction", VCPU_STAT(exit_instruction) },
	{ "exit_program_interruption", VCPU_STAT(exit_program_interruption) },
	{ "exit_instr_and_program_int", VCPU_STAT(exit_instr_and_program) },
	{ "instruction_lctlg", VCPU_STAT(instruction_lctlg) },
	{ "instruction_lctl", VCPU_STAT(instruction_lctl) },
	{ "deliver_emergency_signal", VCPU_STAT(deliver_emergency_signal) },
	{ "deliver_external_call", VCPU_STAT(deliver_external_call) },
	{ "deliver_service_signal", VCPU_STAT(deliver_service_signal) },
	{ "deliver_virtio_interrupt", VCPU_STAT(deliver_virtio_interrupt) },
	{ "deliver_stop_signal", VCPU_STAT(deliver_stop_signal) },
	{ "deliver_prefix_signal", VCPU_STAT(deliver_prefix_signal) },
	{ "deliver_restart_signal", VCPU_STAT(deliver_restart_signal) },
	{ "deliver_program_interruption", VCPU_STAT(deliver_program_int) },
	{ "exit_wait_state", VCPU_STAT(exit_wait_state) },
	{ "instruction_stidp", VCPU_STAT(instruction_stidp) },
	{ "instruction_spx", VCPU_STAT(instruction_spx) },
	{ "instruction_stpx", VCPU_STAT(instruction_stpx) },
	{ "instruction_stap", VCPU_STAT(instruction_stap) },
	{ "instruction_storage_key", VCPU_STAT(instruction_storage_key) },
	{ "instruction_stsch", VCPU_STAT(instruction_stsch) },
	{ "instruction_chsc", VCPU_STAT(instruction_chsc) },
	{ "instruction_stsi", VCPU_STAT(instruction_stsi) },
	{ "instruction_stfl", VCPU_STAT(instruction_stfl) },
	{ "instruction_tprot", VCPU_STAT(instruction_tprot) },
	{ "instruction_sigp_sense", VCPU_STAT(instruction_sigp_sense) },
	{ "instruction_sigp_sense_running", VCPU_STAT(instruction_sigp_sense_running) },
	{ "instruction_sigp_external_call", VCPU_STAT(instruction_sigp_external_call) },
	{ "instruction_sigp_emergency", VCPU_STAT(instruction_sigp_emergency) },
	{ "instruction_sigp_stop", VCPU_STAT(instruction_sigp_stop) },
	{ "instruction_sigp_set_arch", VCPU_STAT(instruction_sigp_arch) },
	{ "instruction_sigp_set_prefix", VCPU_STAT(instruction_sigp_prefix) },
	{ "instruction_sigp_restart", VCPU_STAT(instruction_sigp_restart) },
	{ "diagnose_10", VCPU_STAT(diagnose_10) },
	{ "diagnose_44", VCPU_STAT(diagnose_44) },
	{ NULL }
};

static unsigned long long *facilities;

/* Section: not file related */
int kvm_arch_hardware_enable(void *garbage)
{
	/* every s390 is virtualization enabled ;-) */
	return 0;
}

void kvm_arch_hardware_disable(void *garbage)
{
}

int kvm_arch_hardware_setup(void)
{
	return 0;
}

void kvm_arch_hardware_unsetup(void)
{
}

void kvm_arch_check_processor_compat(void *rtn)
{
}

int kvm_arch_init(void *opaque)
{
	return 0;
}

void kvm_arch_exit(void)
{
}

/* Section: device related */
long kvm_arch_dev_ioctl(struct file *filp,
			unsigned int ioctl, unsigned long arg)
{
	if (ioctl == KVM_S390_ENABLE_SIE)
		return s390_enable_sie();
	return -EINVAL;
}

int kvm_dev_ioctl_check_extension(long ext)
{
	int r;

	switch (ext) {
	case KVM_CAP_S390_PSW:
	case KVM_CAP_S390_GMAP:
	case KVM_CAP_SYNC_MMU:
#ifdef CONFIG_KVM_S390_UCONTROL
	case KVM_CAP_S390_UCONTROL:
#endif
	case KVM_CAP_SYNC_REGS:
		r = 1;
		break;
	default:
		r = 0;
	}
	return r;
}

/* Section: vm related */
/*
 * Get (and clear) the dirty memory log for a memory slot.
 */
int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
			       struct kvm_dirty_log *log)
{
	return 0;
}

long kvm_arch_vm_ioctl(struct file *filp,
		       unsigned int ioctl, unsigned long arg)
{
	struct kvm *kvm = filp->private_data;
	void __user *argp = (void __user *)arg;
	int r;

	switch (ioctl) {
	case KVM_S390_INTERRUPT: {
		struct kvm_s390_interrupt s390int;

		r = -EFAULT;
		if (copy_from_user(&s390int, argp, sizeof(s390int)))
			break;
		r = kvm_s390_inject_vm(kvm, &s390int);
		break;
	}
	default:
		r = -ENOTTY;
	}

	return r;
}

int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
{
	int rc;
	char debug_name[16];

	rc = -EINVAL;
#ifdef CONFIG_KVM_S390_UCONTROL
	if (type & ~KVM_VM_S390_UCONTROL)
		goto out_err;
	if ((type & KVM_VM_S390_UCONTROL) && (!capable(CAP_SYS_ADMIN)))
		goto out_err;
#else
	if (type)
		goto out_err;
#endif

	rc = s390_enable_sie();
	if (rc)
		goto out_err;

	rc = -ENOMEM;

	kvm->arch.sca = (struct sca_block *) get_zeroed_page(GFP_KERNEL);
	if (!kvm->arch.sca)
		goto out_err;

	sprintf(debug_name, "kvm-%u", current->pid);

	kvm->arch.dbf = debug_register(debug_name, 8, 2, 8 * sizeof(long));
	if (!kvm->arch.dbf)
		goto out_nodbf;

	spin_lock_init(&kvm->arch.float_int.lock);
	INIT_LIST_HEAD(&kvm->arch.float_int.list);

	debug_register_view(kvm->arch.dbf, &debug_sprintf_view);
	VM_EVENT(kvm, 3, "%s", "vm created");

	if (type & KVM_VM_S390_UCONTROL) {
		kvm->arch.gmap = NULL;
	} else {
		kvm->arch.gmap = gmap_alloc(current->mm);
		if (!kvm->arch.gmap)
			goto out_nogmap;
	}
	return 0;
out_nogmap:
	debug_unregister(kvm->arch.dbf);
out_nodbf:
	free_page((unsigned long)(kvm->arch.sca));
out_err:
	return rc;
}

void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
{
	VCPU_EVENT(vcpu, 3, "%s", "free cpu");
	if (!kvm_is_ucontrol(vcpu->kvm)) {
		clear_bit(63 - vcpu->vcpu_id,
			  (unsigned long *) &vcpu->kvm->arch.sca->mcn);
		if (vcpu->kvm->arch.sca->cpu[vcpu->vcpu_id].sda ==
		    (__u64) vcpu->arch.sie_block)
			vcpu->kvm->arch.sca->cpu[vcpu->vcpu_id].sda = 0;
	}
	smp_mb();

	if (kvm_is_ucontrol(vcpu->kvm))
		gmap_free(vcpu->arch.gmap);

	free_page((unsigned long)(vcpu->arch.sie_block));
	kvm_vcpu_uninit(vcpu);
	kfree(vcpu);
}

static void kvm_free_vcpus(struct kvm *kvm)
{
	unsigned int i;
	struct kvm_vcpu *vcpu;

	kvm_for_each_vcpu(i, vcpu, kvm)
		kvm_arch_vcpu_destroy(vcpu);

	mutex_lock(&kvm->lock);
	for (i = 0; i < atomic_read(&kvm->online_vcpus); i++)
		kvm->vcpus[i] = NULL;

	atomic_set(&kvm->online_vcpus, 0);
	mutex_unlock(&kvm->lock);
}

void kvm_arch_sync_events(struct kvm *kvm)
{
}

void kvm_arch_destroy_vm(struct kvm *kvm)
{
	kvm_free_vcpus(kvm);
	free_page((unsigned long)(kvm->arch.sca));
	debug_unregister(kvm->arch.dbf);
	if (!kvm_is_ucontrol(kvm))
		gmap_free(kvm->arch.gmap);
}

/* Section: vcpu related */
int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
{
	if (kvm_is_ucontrol(vcpu->kvm)) {
		vcpu->arch.gmap = gmap_alloc(current->mm);
		if (!vcpu->arch.gmap)
			return -ENOMEM;
		return 0;
	}

	vcpu->arch.gmap = vcpu->kvm->arch.gmap;
	vcpu->run->kvm_valid_regs = KVM_SYNC_PREFIX |
				    KVM_SYNC_GPRS |
				    KVM_SYNC_ACRS |
				    KVM_SYNC_CRS;
	return 0;
}

void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu)
{
	/* Nothing todo */
}

void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
{
	save_fp_regs(&vcpu->arch.host_fpregs);
	save_access_regs(vcpu->arch.host_acrs);
	vcpu->arch.guest_fpregs.fpc &= FPC_VALID_MASK;
	restore_fp_regs(&vcpu->arch.guest_fpregs);
	restore_access_regs(vcpu->run->s.regs.acrs);
	gmap_enable(vcpu->arch.gmap);
	atomic_set_mask(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags);
}

void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
{
	atomic_clear_mask(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags);
	gmap_disable(vcpu->arch.gmap);
	save_fp_regs(&vcpu->arch.guest_fpregs);
	save_access_regs(vcpu->run->s.regs.acrs);
	restore_fp_regs(&vcpu->arch.host_fpregs);
	restore_access_regs(vcpu->arch.host_acrs);
}

static void kvm_s390_vcpu_initial_reset(struct kvm_vcpu *vcpu)
{
	/* this equals initial cpu reset in pop, but we don't switch to ESA */
	vcpu->arch.sie_block->gpsw.mask = 0UL;
	vcpu->arch.sie_block->gpsw.addr = 0UL;
	kvm_s390_set_prefix(vcpu, 0);
	vcpu->arch.sie_block->cputm     = 0UL;
	vcpu->arch.sie_block->ckc       = 0UL;
	vcpu->arch.sie_block->todpr     = 0;
	memset(vcpu->arch.sie_block->gcr, 0, 16 * sizeof(__u64));
	vcpu->arch.sie_block->gcr[0]  = 0xE0UL;
	vcpu->arch.sie_block->gcr[14] = 0xC2000000UL;
	vcpu->arch.guest_fpregs.fpc = 0;
	asm volatile("lfpc %0" : : "Q" (vcpu->arch.guest_fpregs.fpc));
	vcpu->arch.sie_block->gbea = 1;
}

int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
{
	atomic_set(&vcpu->arch.sie_block->cpuflags, CPUSTAT_ZARCH |
						    CPUSTAT_SM |
						    CPUSTAT_STOPPED);
	vcpu->arch.sie_block->ecb   = 6;
	vcpu->arch.sie_block->eca   = 0xC1002001U;
	vcpu->arch.sie_block->fac   = (int) (long) facilities;
	hrtimer_init(&vcpu->arch.ckc_timer, CLOCK_REALTIME, HRTIMER_MODE_ABS);
	tasklet_init(&vcpu->arch.tasklet, kvm_s390_tasklet,
		     (unsigned long) vcpu);
	vcpu->arch.ckc_timer.function = kvm_s390_idle_wakeup;
	get_cpu_id(&vcpu->arch.cpu_id);
	vcpu->arch.cpu_id.version = 0xff;
	return 0;
}

struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm,
				      unsigned int id)
{
	struct kvm_vcpu *vcpu;
	int rc = -EINVAL;

	if (id >= KVM_MAX_VCPUS)
		goto out;

	rc = -ENOMEM;

	vcpu = kzalloc(sizeof(struct kvm_vcpu), GFP_KERNEL);
	if (!vcpu)
		goto out;

	vcpu->arch.sie_block = (struct kvm_s390_sie_block *)
					get_zeroed_page(GFP_KERNEL);

	if (!vcpu->arch.sie_block)
		goto out_free_cpu;

	vcpu->arch.sie_block->icpua = id;
	if (!kvm_is_ucontrol(kvm)) {
		if (!kvm->arch.sca) {
			WARN_ON_ONCE(1);
			goto out_free_cpu;
		}
		if (!kvm->arch.sca->cpu[id].sda)
			kvm->arch.sca->cpu[id].sda =
				(__u64) vcpu->arch.sie_block;
		vcpu->arch.sie_block->scaoh =
			(__u32)(((__u64)kvm->arch.sca) >> 32);
		vcpu->arch.sie_block->scaol = (__u32)(__u64)kvm->arch.sca;
		set_bit(63 - id, (unsigned long *) &kvm->arch.sca->mcn);
	}

	spin_lock_init(&vcpu->arch.local_int.lock);
	INIT_LIST_HEAD(&vcpu->arch.local_int.list);
	vcpu->arch.local_int.float_int = &kvm->arch.float_int;
	spin_lock(&kvm->arch.float_int.lock);
	kvm->arch.float_int.local_int[id] = &vcpu->arch.local_int;
	init_waitqueue_head(&vcpu->arch.local_int.wq);
	vcpu->arch.local_int.cpuflags = &vcpu->arch.sie_block->cpuflags;
	spin_unlock(&kvm->arch.float_int.lock);

	rc = kvm_vcpu_init(vcpu, kvm, id);
	if (rc)
		goto out_free_sie_block;
	VM_EVENT(kvm, 3, "create cpu %d at %p, sie block at %p", id, vcpu,
		 vcpu->arch.sie_block);

	return vcpu;
out_free_sie_block:
	free_page((unsigned long)(vcpu->arch.sie_block));
out_free_cpu:
	kfree(vcpu);
out:
	return ERR_PTR(rc);
}

int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
{
	/* kvm common code refers to this, but never calls it */
	BUG();
	return 0;
}

static int kvm_arch_vcpu_ioctl_initial_reset(struct kvm_vcpu *vcpu)
{
	kvm_s390_vcpu_initial_reset(vcpu);
	return 0;
}

int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
{
	memcpy(&vcpu->run->s.regs.gprs, &regs->gprs, sizeof(regs->gprs));
	return 0;
}

int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
{
	memcpy(&regs->gprs, &vcpu->run->s.regs.gprs, sizeof(regs->gprs));
	return 0;
}

int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
				  struct kvm_sregs *sregs)
{
	memcpy(&vcpu->run->s.regs.acrs, &sregs->acrs, sizeof(sregs->acrs));
	memcpy(&vcpu->arch.sie_block->gcr, &sregs->crs, sizeof(sregs->crs));
	restore_access_regs(vcpu->run->s.regs.acrs);
	return 0;
}

int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
				  struct kvm_sregs *sregs)
{
	memcpy(&sregs->acrs, &vcpu->run->s.regs.acrs, sizeof(sregs->acrs));
	memcpy(&sregs->crs, &vcpu->arch.sie_block->gcr, sizeof(sregs->crs));
	return 0;
}

int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
{
	memcpy(&vcpu->arch.guest_fpregs.fprs, &fpu->fprs, sizeof(fpu->fprs));
	vcpu->arch.guest_fpregs.fpc = fpu->fpc & FPC_VALID_MASK;
	restore_fp_regs(&vcpu->arch.guest_fpregs);
	return 0;
}

int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
{
	memcpy(&fpu->fprs, &vcpu->arch.guest_fpregs.fprs, sizeof(fpu->fprs));
	fpu->fpc = vcpu->arch.guest_fpregs.fpc;
	return 0;
}

static int kvm_arch_vcpu_ioctl_set_initial_psw(struct kvm_vcpu *vcpu, psw_t psw)
{
	int rc = 0;

	if (!(atomic_read(&vcpu->arch.sie_block->cpuflags) & CPUSTAT_STOPPED))
		rc = -EBUSY;
	else {
		vcpu->run->psw_mask = psw.mask;
		vcpu->run->psw_addr = psw.addr;
	}
	return rc;
}

int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
				  struct kvm_translation *tr)
{
	return -EINVAL; /* not implemented yet */
}

int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
					struct kvm_guest_debug *dbg)
{
	return -EINVAL; /* not implemented yet */
}

int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
				    struct kvm_mp_state *mp_state)
{
	return -EINVAL; /* not implemented yet */
}

int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
				    struct kvm_mp_state *mp_state)
{
	return -EINVAL; /* not implemented yet */
}

static int __vcpu_run(struct kvm_vcpu *vcpu)
{
	int rc;

	memcpy(&vcpu->arch.sie_block->gg14, &vcpu->run->s.regs.gprs[14], 16);

	if (need_resched())
		schedule();

	if (test_thread_flag(TIF_MCCK_PENDING))
		s390_handle_mcck();

	if (!kvm_is_ucontrol(vcpu->kvm))
		kvm_s390_deliver_pending_interrupts(vcpu);

	vcpu->arch.sie_block->icptcode = 0;
	local_irq_disable();
	kvm_guest_enter();
	local_irq_enable();
	VCPU_EVENT(vcpu, 6, "entering sie flags %x",
		   atomic_read(&vcpu->arch.sie_block->cpuflags));
	rc = sie64a(vcpu->arch.sie_block, vcpu->run->s.regs.gprs);
	if (rc) {
		if (kvm_is_ucontrol(vcpu->kvm)) {
			rc = SIE_INTERCEPT_UCONTROL;
		} else {
			VCPU_EVENT(vcpu, 3, "%s", "fault in sie instruction");
			kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
			rc = 0;
		}
	}
	VCPU_EVENT(vcpu, 6, "exit sie icptcode %d",
		   vcpu->arch.sie_block->icptcode);
	local_irq_disable();
	kvm_guest_exit();
	local_irq_enable();

	memcpy(&vcpu->run->s.regs.gprs[14], &vcpu->arch.sie_block->gg14, 16);
	return rc;
}

int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
{
	int rc;
	sigset_t sigsaved;

rerun_vcpu:
	if (vcpu->sigset_active)
		sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);

	atomic_clear_mask(CPUSTAT_STOPPED, &vcpu->arch.sie_block->cpuflags);

	BUG_ON(vcpu->kvm->arch.float_int.local_int[vcpu->vcpu_id] == NULL);

	switch (kvm_run->exit_reason) {
	case KVM_EXIT_S390_SIEIC:
	case KVM_EXIT_UNKNOWN:
	case KVM_EXIT_INTR:
	case KVM_EXIT_S390_RESET:
	case KVM_EXIT_S390_UCONTROL:
		break;
	default:
		BUG();
	}

	vcpu->arch.sie_block->gpsw.mask = kvm_run->psw_mask;
	vcpu->arch.sie_block->gpsw.addr = kvm_run->psw_addr;
	if (kvm_run->kvm_dirty_regs & KVM_SYNC_PREFIX) {
		kvm_run->kvm_dirty_regs &= ~KVM_SYNC_PREFIX;
		kvm_s390_set_prefix(vcpu, kvm_run->s.regs.prefix);
	}
	if (kvm_run->kvm_dirty_regs & KVM_SYNC_CRS) {
		kvm_run->kvm_dirty_regs &= ~KVM_SYNC_CRS;
		memcpy(&vcpu->arch.sie_block->gcr, &kvm_run->s.regs.crs, 128);
		kvm_s390_set_prefix(vcpu, kvm_run->s.regs.prefix);
	}

	might_fault();

	do {
		rc = __vcpu_run(vcpu);
		if (rc)
			break;
		if (kvm_is_ucontrol(vcpu->kvm))
			rc = -EOPNOTSUPP;
		else
			rc = kvm_handle_sie_intercept(vcpu);
	} while (!signal_pending(current) && !rc);

	if (rc == SIE_INTERCEPT_RERUNVCPU)
		goto rerun_vcpu;

	if (signal_pending(current) && !rc) {
		kvm_run->exit_reason = KVM_EXIT_INTR;
		rc = -EINTR;
	}

#ifdef CONFIG_KVM_S390_UCONTROL
	if (rc == SIE_INTERCEPT_UCONTROL) {
		kvm_run->exit_reason = KVM_EXIT_S390_UCONTROL;
		kvm_run->s390_ucontrol.trans_exc_code =
			current->thread.gmap_addr;
		kvm_run->s390_ucontrol.pgm_code = 0x10;
		rc = 0;
	}
#endif

	if (rc == -EOPNOTSUPP) {
		/* intercept cannot be handled in-kernel, prepare kvm-run */
		kvm_run->exit_reason         = KVM_EXIT_S390_SIEIC;
		kvm_run->s390_sieic.icptcode = vcpu->arch.sie_block->icptcode;
		kvm_run->s390_sieic.ipa      = vcpu->arch.sie_block->ipa;
		kvm_run->s390_sieic.ipb      = vcpu->arch.sie_block->ipb;
		rc = 0;
	}

	if (rc == -EREMOTE) {
		/* intercept was handled, but userspace support is needed
		 * kvm_run has been prepared by the handler */
		rc = 0;
	}

	kvm_run->psw_mask     = vcpu->arch.sie_block->gpsw.mask;
	kvm_run->psw_addr     = vcpu->arch.sie_block->gpsw.addr;
	kvm_run->s.regs.prefix = vcpu->arch.sie_block->prefix;
	memcpy(&kvm_run->s.regs.crs, &vcpu->arch.sie_block->gcr, 128);

	if (vcpu->sigset_active)
		sigprocmask(SIG_SETMASK, &sigsaved, NULL);

	vcpu->stat.exit_userspace++;
	return rc;
}

static int __guestcopy(struct kvm_vcpu *vcpu, u64 guestdest, void *from,
		       unsigned long n, int prefix)
{
	if (prefix)
		return copy_to_guest(vcpu, guestdest, from, n);
	else
		return copy_to_guest_absolute(vcpu, guestdest, from, n);
}

/*
 * store status at address
 * we use have two special cases:
 * KVM_S390_STORE_STATUS_NOADDR: -> 0x1200 on 64 bit
 * KVM_S390_STORE_STATUS_PREFIXED: -> prefix
 */
int kvm_s390_vcpu_store_status(struct kvm_vcpu *vcpu, unsigned long addr)
{
	unsigned char archmode = 1;
	int prefix;

	if (addr == KVM_S390_STORE_STATUS_NOADDR) {
		if (copy_to_guest_absolute(vcpu, 163ul, &archmode, 1))
			return -EFAULT;
		addr = SAVE_AREA_BASE;
		prefix = 0;
	} else if (addr == KVM_S390_STORE_STATUS_PREFIXED) {
		if (copy_to_guest(vcpu, 163ul, &archmode, 1))
			return -EFAULT;
		addr = SAVE_AREA_BASE;
		prefix = 1;
	} else
		prefix = 0;

	if (__guestcopy(vcpu, addr + offsetof(struct save_area, fp_regs),
			vcpu->arch.guest_fpregs.fprs, 128, prefix))
		return -EFAULT;

	if (__guestcopy(vcpu, addr + offsetof(struct save_area, gp_regs),
			vcpu->run->s.regs.gprs, 128, prefix))
		return -EFAULT;

	if (__guestcopy(vcpu, addr + offsetof(struct save_area, psw),
			&vcpu->arch.sie_block->gpsw, 16, prefix))
		return -EFAULT;

	if (__guestcopy(vcpu, addr + offsetof(struct save_area, pref_reg),
			&vcpu->arch.sie_block->prefix, 4, prefix))
		return -EFAULT;

	if (__guestcopy(vcpu,
			addr + offsetof(struct save_area, fp_ctrl_reg),
			&vcpu->arch.guest_fpregs.fpc, 4, prefix))
		return -EFAULT;

	if (__guestcopy(vcpu, addr + offsetof(struct save_area, tod_reg),
			&vcpu->arch.sie_block->todpr, 4, prefix))
		return -EFAULT;

	if (__guestcopy(vcpu, addr + offsetof(struct save_area, timer),
			&vcpu->arch.sie_block->cputm, 8, prefix))
		return -EFAULT;

	if (__guestcopy(vcpu, addr + offsetof(struct save_area, clk_cmp),
			&vcpu->arch.sie_block->ckc, 8, prefix))
		return -EFAULT;

	if (__guestcopy(vcpu, addr + offsetof(struct save_area, acc_regs),
			&vcpu->run->s.regs.acrs, 64, prefix))
		return -EFAULT;

	if (__guestcopy(vcpu,
			addr + offsetof(struct save_area, ctrl_regs),
			&vcpu->arch.sie_block->gcr, 128, prefix))
		return -EFAULT;
	return 0;
}

long kvm_arch_vcpu_ioctl(struct file *filp,
			 unsigned int ioctl, unsigned long arg)
{
	struct kvm_vcpu *vcpu = filp->private_data;
	void __user *argp = (void __user *)arg;
	long r;

	switch (ioctl) {
	case KVM_S390_INTERRUPT: {
		struct kvm_s390_interrupt s390int;

		r = -EFAULT;
		if (copy_from_user(&s390int, argp, sizeof(s390int)))
			break;
		r = kvm_s390_inject_vcpu(vcpu, &s390int);
		break;
	}
	case KVM_S390_STORE_STATUS:
		r = kvm_s390_vcpu_store_status(vcpu, arg);
		break;
	case KVM_S390_SET_INITIAL_PSW: {
		psw_t psw;

		r = -EFAULT;
		if (copy_from_user(&psw, argp, sizeof(psw)))
			break;
		r = kvm_arch_vcpu_ioctl_set_initial_psw(vcpu, psw);
		break;
	}
	case KVM_S390_INITIAL_RESET:
		r = kvm_arch_vcpu_ioctl_initial_reset(vcpu);
		break;
#ifdef CONFIG_KVM_S390_UCONTROL
	case KVM_S390_UCAS_MAP: {
		struct kvm_s390_ucas_mapping ucasmap;

		if (copy_from_user(&ucasmap, argp, sizeof(ucasmap))) {
			r = -EFAULT;
			break;
		}

		if (!kvm_is_ucontrol(vcpu->kvm)) {
			r = -EINVAL;
			break;
		}

		r = gmap_map_segment(vcpu->arch.gmap, ucasmap.user_addr,
				     ucasmap.vcpu_addr, ucasmap.length);
		break;
	}
	case KVM_S390_UCAS_UNMAP: {
		struct kvm_s390_ucas_mapping ucasmap;

		if (copy_from_user(&ucasmap, argp, sizeof(ucasmap))) {
			r = -EFAULT;
			break;
		}

		if (!kvm_is_ucontrol(vcpu->kvm)) {
			r = -EINVAL;
			break;
		}

		r = gmap_unmap_segment(vcpu->arch.gmap, ucasmap.vcpu_addr,
			ucasmap.length);
		break;
	}
#endif
	case KVM_S390_VCPU_FAULT: {
		r = gmap_fault(arg, vcpu->arch.gmap);
		if (!IS_ERR_VALUE(r))
			r = 0;
		break;
	}
	default:
		r = -ENOTTY;
	}
	return r;
}

int kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
{
#ifdef CONFIG_KVM_S390_UCONTROL
	if ((vmf->pgoff == KVM_S390_SIE_PAGE_OFFSET)
		 && (kvm_is_ucontrol(vcpu->kvm))) {
		vmf->page = virt_to_page(vcpu->arch.sie_block);
		get_page(vmf->page);
		return 0;
	}
#endif
	return VM_FAULT_SIGBUS;
}

void kvm_arch_free_memslot(struct kvm_memory_slot *free,
			   struct kvm_memory_slot *dont)
{
}

int kvm_arch_create_memslot(struct kvm_memory_slot *slot, unsigned long npages)
{
	return 0;
}

/* Section: memory related */
int kvm_arch_prepare_memory_region(struct kvm *kvm,
				   struct kvm_memory_slot *memslot,
				   struct kvm_memory_slot old,
				   struct kvm_userspace_memory_region *mem,
				   int user_alloc)
{
	/* A few sanity checks. We can have exactly one memory slot which has
	   to start at guest virtual zero and which has to be located at a
	   page boundary in userland and which has to end at a page boundary.
	   The memory in userland is ok to be fragmented into various different
	   vmas. It is okay to mmap() and munmap() stuff in this slot after
	   doing this call at any time */

	if (mem->slot)
		return -EINVAL;

	if (mem->guest_phys_addr)
		return -EINVAL;

	if (mem->userspace_addr & 0xffffful)
		return -EINVAL;

	if (mem->memory_size & 0xffffful)
		return -EINVAL;

	if (!user_alloc)
		return -EINVAL;

	return 0;
}

void kvm_arch_commit_memory_region(struct kvm *kvm,
				struct kvm_userspace_memory_region *mem,
				struct kvm_memory_slot old,
				int user_alloc)
{
	int rc;


	rc = gmap_map_segment(kvm->arch.gmap, mem->userspace_addr,
		mem->guest_phys_addr, mem->memory_size);
	if (rc)
		printk(KERN_WARNING "kvm-s390: failed to commit memory region\n");
	return;
}

void kvm_arch_flush_shadow(struct kvm *kvm)
{
}

static int __init kvm_s390_init(void)
{
	int ret;
	ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
	if (ret)
		return ret;

	/*
	 * guests can ask for up to 255+1 double words, we need a full page
	 * to hold the maximum amount of facilities. On the other hand, we
	 * only set facilities that are known to work in KVM.
	 */
	facilities = (unsigned long long *) get_zeroed_page(GFP_KERNEL|GFP_DMA);
	if (!facilities) {
		kvm_exit();
		return -ENOMEM;
	}
	memcpy(facilities, S390_lowcore.stfle_fac_list, 16);
	facilities[0] &= 0xff00fff3f47c0000ULL;
	facilities[1] &= 0x201c000000000000ULL;
	return 0;
}

static void __exit kvm_s390_exit(void)
{
	free_page((unsigned long) facilities);
	kvm_exit();
}

module_init(kvm_s390_init);
module_exit(kvm_s390_exit);