1/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License.  See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * KVM/MIPS: Support for hardware virtualization extensions
7 *
8 * Copyright (C) 2012  MIPS Technologies, Inc.  All rights reserved.
9 * Authors: Yann Le Du <ledu@kymasys.com>
10 */
11
12#include <linux/errno.h>
13#include <linux/err.h>
14#include <linux/module.h>
15#include <linux/preempt.h>
16#include <linux/vmalloc.h>
17#include <asm/cacheflush.h>
18#include <asm/cacheops.h>
19#include <asm/cmpxchg.h>
20#include <asm/fpu.h>
21#include <asm/hazards.h>
22#include <asm/inst.h>
23#include <asm/mmu_context.h>
24#include <asm/r4kcache.h>
25#include <asm/time.h>
26#include <asm/tlb.h>
27#include <asm/tlbex.h>
28
29#include <linux/kvm_host.h>
30
31#include "interrupt.h"
32#ifdef CONFIG_CPU_LOONGSON64
33#include "loongson_regs.h"
34#endif
35
36#include "trace.h"
37
38/* Pointers to last VCPU loaded on each physical CPU */
39static struct kvm_vcpu *last_vcpu[NR_CPUS];
40/* Pointers to last VCPU executed on each physical CPU */
41static struct kvm_vcpu *last_exec_vcpu[NR_CPUS];
42
43/*
44 * Number of guest VTLB entries to use, so we can catch inconsistency between
45 * CPUs.
46 */
47static unsigned int kvm_vz_guest_vtlb_size;
48
49static inline long kvm_vz_read_gc0_ebase(void)
50{
51	if (sizeof(long) == 8 && cpu_has_ebase_wg)
52		return read_gc0_ebase_64();
53	else
54		return read_gc0_ebase();
55}
56
57static inline void kvm_vz_write_gc0_ebase(long v)
58{
59	/*
60	 * First write with WG=1 to write upper bits, then write again in case
61	 * WG should be left at 0.
62	 * write_gc0_ebase_64() is no longer UNDEFINED since R6.
63	 */
64	if (sizeof(long) == 8 &&
65	    (cpu_has_mips64r6 || cpu_has_ebase_wg)) {
66		write_gc0_ebase_64(v | MIPS_EBASE_WG);
67		write_gc0_ebase_64(v);
68	} else {
69		write_gc0_ebase(v | MIPS_EBASE_WG);
70		write_gc0_ebase(v);
71	}
72}
73
74/*
75 * These Config bits may be writable by the guest:
76 * Config:	[K23, KU] (!TLB), K0
77 * Config1:	(none)
78 * Config2:	[TU, SU] (impl)
79 * Config3:	ISAOnExc
80 * Config4:	FTLBPageSize
81 * Config5:	K, CV, MSAEn, UFE, FRE, SBRI, UFR
82 */
83
84static inline unsigned int kvm_vz_config_guest_wrmask(struct kvm_vcpu *vcpu)
85{
86	return CONF_CM_CMASK;
87}
88
89static inline unsigned int kvm_vz_config1_guest_wrmask(struct kvm_vcpu *vcpu)
90{
91	return 0;
92}
93
94static inline unsigned int kvm_vz_config2_guest_wrmask(struct kvm_vcpu *vcpu)
95{
96	return 0;
97}
98
99static inline unsigned int kvm_vz_config3_guest_wrmask(struct kvm_vcpu *vcpu)
100{
101	return MIPS_CONF3_ISA_OE;
102}
103
104static inline unsigned int kvm_vz_config4_guest_wrmask(struct kvm_vcpu *vcpu)
105{
106	/* no need to be exact */
107	return MIPS_CONF4_VFTLBPAGESIZE;
108}
109
110static inline unsigned int kvm_vz_config5_guest_wrmask(struct kvm_vcpu *vcpu)
111{
112	unsigned int mask = MIPS_CONF5_K | MIPS_CONF5_CV | MIPS_CONF5_SBRI;
113
114	/* Permit MSAEn changes if MSA supported and enabled */
115	if (kvm_mips_guest_has_msa(&vcpu->arch))
116		mask |= MIPS_CONF5_MSAEN;
117
118	/*
119	 * Permit guest FPU mode changes if FPU is enabled and the relevant
120	 * feature exists according to FIR register.
121	 */
122	if (kvm_mips_guest_has_fpu(&vcpu->arch)) {
123		if (cpu_has_ufr)
124			mask |= MIPS_CONF5_UFR;
125		if (cpu_has_fre)
126			mask |= MIPS_CONF5_FRE | MIPS_CONF5_UFE;
127	}
128
129	return mask;
130}
131
132static inline unsigned int kvm_vz_config6_guest_wrmask(struct kvm_vcpu *vcpu)
133{
134	return LOONGSON_CONF6_INTIMER | LOONGSON_CONF6_EXTIMER;
135}
136
137/*
138 * VZ optionally allows these additional Config bits to be written by root:
139 * Config:	M, [MT]
140 * Config1:	M, [MMUSize-1, C2, MD, PC, WR, CA], FP
141 * Config2:	M
142 * Config3:	M, MSAP, [BPG], ULRI, [DSP2P, DSPP], CTXTC, [ITL, LPA, VEIC,
143 *		VInt, SP, CDMM, MT, SM, TL]
144 * Config4:	M, [VTLBSizeExt, MMUSizeExt]
145 * Config5:	MRP
146 */
147
148static inline unsigned int kvm_vz_config_user_wrmask(struct kvm_vcpu *vcpu)
149{
150	return kvm_vz_config_guest_wrmask(vcpu) | MIPS_CONF_M;
151}
152
153static inline unsigned int kvm_vz_config1_user_wrmask(struct kvm_vcpu *vcpu)
154{
155	unsigned int mask = kvm_vz_config1_guest_wrmask(vcpu) | MIPS_CONF_M;
156
157	/* Permit FPU to be present if FPU is supported */
158	if (kvm_mips_guest_can_have_fpu(&vcpu->arch))
159		mask |= MIPS_CONF1_FP;
160
161	return mask;
162}
163
164static inline unsigned int kvm_vz_config2_user_wrmask(struct kvm_vcpu *vcpu)
165{
166	return kvm_vz_config2_guest_wrmask(vcpu) | MIPS_CONF_M;
167}
168
169static inline unsigned int kvm_vz_config3_user_wrmask(struct kvm_vcpu *vcpu)
170{
171	unsigned int mask = kvm_vz_config3_guest_wrmask(vcpu) | MIPS_CONF_M |
172		MIPS_CONF3_ULRI | MIPS_CONF3_CTXTC;
173
174	/* Permit MSA to be present if MSA is supported */
175	if (kvm_mips_guest_can_have_msa(&vcpu->arch))
176		mask |= MIPS_CONF3_MSA;
177
178	return mask;
179}
180
181static inline unsigned int kvm_vz_config4_user_wrmask(struct kvm_vcpu *vcpu)
182{
183	return kvm_vz_config4_guest_wrmask(vcpu) | MIPS_CONF_M;
184}
185
186static inline unsigned int kvm_vz_config5_user_wrmask(struct kvm_vcpu *vcpu)
187{
188	return kvm_vz_config5_guest_wrmask(vcpu) | MIPS_CONF5_MRP;
189}
190
191static inline unsigned int kvm_vz_config6_user_wrmask(struct kvm_vcpu *vcpu)
192{
193	return kvm_vz_config6_guest_wrmask(vcpu) |
194		LOONGSON_CONF6_SFBEN | LOONGSON_CONF6_FTLBDIS;
195}
196
197static gpa_t kvm_vz_gva_to_gpa_cb(gva_t gva)
198{
199	/* VZ guest has already converted gva to gpa */
200	return gva;
201}
202
203static void kvm_vz_queue_irq(struct kvm_vcpu *vcpu, unsigned int priority)
204{
205	set_bit(priority, &vcpu->arch.pending_exceptions);
206	clear_bit(priority, &vcpu->arch.pending_exceptions_clr);
207}
208
209static void kvm_vz_dequeue_irq(struct kvm_vcpu *vcpu, unsigned int priority)
210{
211	clear_bit(priority, &vcpu->arch.pending_exceptions);
212	set_bit(priority, &vcpu->arch.pending_exceptions_clr);
213}
214
215static void kvm_vz_queue_timer_int_cb(struct kvm_vcpu *vcpu)
216{
217	/*
218	 * timer expiry is asynchronous to vcpu execution therefore defer guest
219	 * cp0 accesses
220	 */
221	kvm_vz_queue_irq(vcpu, MIPS_EXC_INT_TIMER);
222}
223
224static void kvm_vz_dequeue_timer_int_cb(struct kvm_vcpu *vcpu)
225{
226	/*
227	 * timer expiry is asynchronous to vcpu execution therefore defer guest
228	 * cp0 accesses
229	 */
230	kvm_vz_dequeue_irq(vcpu, MIPS_EXC_INT_TIMER);
231}
232
233static void kvm_vz_queue_io_int_cb(struct kvm_vcpu *vcpu,
234				   struct kvm_mips_interrupt *irq)
235{
236	int intr = (int)irq->irq;
237
238	/*
239	 * interrupts are asynchronous to vcpu execution therefore defer guest
240	 * cp0 accesses
241	 */
242	kvm_vz_queue_irq(vcpu, kvm_irq_to_priority(intr));
243}
244
245static void kvm_vz_dequeue_io_int_cb(struct kvm_vcpu *vcpu,
246				     struct kvm_mips_interrupt *irq)
247{
248	int intr = (int)irq->irq;
249
250	/*
251	 * interrupts are asynchronous to vcpu execution therefore defer guest
252	 * cp0 accesses
253	 */
254	kvm_vz_dequeue_irq(vcpu, kvm_irq_to_priority(-intr));
255}
256
257static int kvm_vz_irq_deliver_cb(struct kvm_vcpu *vcpu, unsigned int priority,
258				 u32 cause)
259{
260	u32 irq = (priority < MIPS_EXC_MAX) ?
261		kvm_priority_to_irq[priority] : 0;
262
263	switch (priority) {
264	case MIPS_EXC_INT_TIMER:
265		set_gc0_cause(C_TI);
266		break;
267
268	case MIPS_EXC_INT_IO_1:
269	case MIPS_EXC_INT_IO_2:
270	case MIPS_EXC_INT_IPI_1:
271	case MIPS_EXC_INT_IPI_2:
272		if (cpu_has_guestctl2)
273			set_c0_guestctl2(irq);
274		else
275			set_gc0_cause(irq);
276		break;
277
278	default:
279		break;
280	}
281
282	clear_bit(priority, &vcpu->arch.pending_exceptions);
283	return 1;
284}
285
286static int kvm_vz_irq_clear_cb(struct kvm_vcpu *vcpu, unsigned int priority,
287			       u32 cause)
288{
289	u32 irq = (priority < MIPS_EXC_MAX) ?
290		kvm_priority_to_irq[priority] : 0;
291
292	switch (priority) {
293	case MIPS_EXC_INT_TIMER:
294		/*
295		 * Explicitly clear irq associated with Cause.IP[IPTI]
296		 * if GuestCtl2 virtual interrupt register not
297		 * supported or if not using GuestCtl2 Hardware Clear.
298		 */
299		if (cpu_has_guestctl2) {
300			if (!(read_c0_guestctl2() & (irq << 14)))
301				clear_c0_guestctl2(irq);
302		} else {
303			clear_gc0_cause(irq);
304		}
305		break;
306
307	case MIPS_EXC_INT_IO_1:
308	case MIPS_EXC_INT_IO_2:
309	case MIPS_EXC_INT_IPI_1:
310	case MIPS_EXC_INT_IPI_2:
311		/* Clear GuestCtl2.VIP irq if not using Hardware Clear */
312		if (cpu_has_guestctl2) {
313			if (!(read_c0_guestctl2() & (irq << 14)))
314				clear_c0_guestctl2(irq);
315		} else {
316			clear_gc0_cause(irq);
317		}
318		break;
319
320	default:
321		break;
322	}
323
324	clear_bit(priority, &vcpu->arch.pending_exceptions_clr);
325	return 1;
326}
327
328/*
329 * VZ guest timer handling.
330 */
331
332/**
333 * kvm_vz_should_use_htimer() - Find whether to use the VZ hard guest timer.
334 * @vcpu:	Virtual CPU.
335 *
336 * Returns:	true if the VZ GTOffset & real guest CP0_Count should be used
337 *		instead of software emulation of guest timer.
338 *		false otherwise.
339 */
340static bool kvm_vz_should_use_htimer(struct kvm_vcpu *vcpu)
341{
342	if (kvm_mips_count_disabled(vcpu))
343		return false;
344
345	/* Chosen frequency must match real frequency */
346	if (mips_hpt_frequency != vcpu->arch.count_hz)
347		return false;
348
349	/* We don't support a CP0_GTOffset with fewer bits than CP0_Count */
350	if (current_cpu_data.gtoffset_mask != 0xffffffff)
351		return false;
352
353	return true;
354}
355
356/**
357 * _kvm_vz_restore_stimer() - Restore soft timer state.
358 * @vcpu:	Virtual CPU.
359 * @compare:	CP0_Compare register value, restored by caller.
360 * @cause:	CP0_Cause register to restore.
361 *
362 * Restore VZ state relating to the soft timer. The hard timer can be enabled
363 * later.
364 */
365static void _kvm_vz_restore_stimer(struct kvm_vcpu *vcpu, u32 compare,
366				   u32 cause)
367{
368	/*
369	 * Avoid spurious counter interrupts by setting Guest CP0_Count to just
370	 * after Guest CP0_Compare.
371	 */
372	write_c0_gtoffset(compare - read_c0_count());
373
374	back_to_back_c0_hazard();
375	write_gc0_cause(cause);
376}
377
378/**
379 * _kvm_vz_restore_htimer() - Restore hard timer state.
380 * @vcpu:	Virtual CPU.
381 * @compare:	CP0_Compare register value, restored by caller.
382 * @cause:	CP0_Cause register to restore.
383 *
384 * Restore hard timer Guest.Count & Guest.Cause taking care to preserve the
385 * value of Guest.CP0_Cause.TI while restoring Guest.CP0_Cause.
386 */
387static void _kvm_vz_restore_htimer(struct kvm_vcpu *vcpu,
388				   u32 compare, u32 cause)
389{
390	u32 start_count, after_count;
391	unsigned long flags;
392
393	/*
394	 * Freeze the soft-timer and sync the guest CP0_Count with it. We do
395	 * this with interrupts disabled to avoid latency.
396	 */
397	local_irq_save(flags);
398	kvm_mips_freeze_hrtimer(vcpu, &start_count);
399	write_c0_gtoffset(start_count - read_c0_count());
400	local_irq_restore(flags);
401
402	/* restore guest CP0_Cause, as TI may already be set */
403	back_to_back_c0_hazard();
404	write_gc0_cause(cause);
405
406	/*
407	 * The above sequence isn't atomic and would result in lost timer
408	 * interrupts if we're not careful. Detect if a timer interrupt is due
409	 * and assert it.
410	 */
411	back_to_back_c0_hazard();
412	after_count = read_gc0_count();
413	if (after_count - start_count > compare - start_count - 1)
414		kvm_vz_queue_irq(vcpu, MIPS_EXC_INT_TIMER);
415}
416
417/**
418 * kvm_vz_restore_timer() - Restore timer state.
419 * @vcpu:	Virtual CPU.
420 *
421 * Restore soft timer state from saved context.
422 */
423static void kvm_vz_restore_timer(struct kvm_vcpu *vcpu)
424{
425	struct mips_coproc *cop0 = &vcpu->arch.cop0;
426	u32 cause, compare;
427
428	compare = kvm_read_sw_gc0_compare(cop0);
429	cause = kvm_read_sw_gc0_cause(cop0);
430
431	write_gc0_compare(compare);
432	_kvm_vz_restore_stimer(vcpu, compare, cause);
433}
434
435/**
436 * kvm_vz_acquire_htimer() - Switch to hard timer state.
437 * @vcpu:	Virtual CPU.
438 *
439 * Restore hard timer state on top of existing soft timer state if possible.
440 *
441 * Since hard timer won't remain active over preemption, preemption should be
442 * disabled by the caller.
443 */
444void kvm_vz_acquire_htimer(struct kvm_vcpu *vcpu)
445{
446	u32 gctl0;
447
448	gctl0 = read_c0_guestctl0();
449	if (!(gctl0 & MIPS_GCTL0_GT) && kvm_vz_should_use_htimer(vcpu)) {
450		/* enable guest access to hard timer */
451		write_c0_guestctl0(gctl0 | MIPS_GCTL0_GT);
452
453		_kvm_vz_restore_htimer(vcpu, read_gc0_compare(),
454				       read_gc0_cause());
455	}
456}
457
458/**
459 * _kvm_vz_save_htimer() - Switch to software emulation of guest timer.
460 * @vcpu:	Virtual CPU.
461 * @out_compare: Pointer to write compare value to.
462 * @out_cause:	Pointer to write cause value to.
463 *
464 * Save VZ guest timer state and switch to software emulation of guest CP0
465 * timer. The hard timer must already be in use, so preemption should be
466 * disabled.
467 */
468static void _kvm_vz_save_htimer(struct kvm_vcpu *vcpu,
469				u32 *out_compare, u32 *out_cause)
470{
471	u32 cause, compare, before_count, end_count;
472	ktime_t before_time;
473
474	compare = read_gc0_compare();
475	*out_compare = compare;
476
477	before_time = ktime_get();
478
479	/*
480	 * Record the CP0_Count *prior* to saving CP0_Cause, so we have a time
481	 * at which no pending timer interrupt is missing.
482	 */
483	before_count = read_gc0_count();
484	back_to_back_c0_hazard();
485	cause = read_gc0_cause();
486	*out_cause = cause;
487
488	/*
489	 * Record a final CP0_Count which we will transfer to the soft-timer.
490	 * This is recorded *after* saving CP0_Cause, so we don't get any timer
491	 * interrupts from just after the final CP0_Count point.
492	 */
493	back_to_back_c0_hazard();
494	end_count = read_gc0_count();
495
496	/*
497	 * The above sequence isn't atomic, so we could miss a timer interrupt
498	 * between reading CP0_Cause and end_count. Detect and record any timer
499	 * interrupt due between before_count and end_count.
500	 */
501	if (end_count - before_count > compare - before_count - 1)
502		kvm_vz_queue_irq(vcpu, MIPS_EXC_INT_TIMER);
503
504	/*
505	 * Restore soft-timer, ignoring a small amount of negative drift due to
506	 * delay between freeze_hrtimer and setting CP0_GTOffset.
507	 */
508	kvm_mips_restore_hrtimer(vcpu, before_time, end_count, -0x10000);
509}
510
511/**
512 * kvm_vz_save_timer() - Save guest timer state.
513 * @vcpu:	Virtual CPU.
514 *
515 * Save VZ guest timer state and switch to soft guest timer if hard timer was in
516 * use.
517 */
518static void kvm_vz_save_timer(struct kvm_vcpu *vcpu)
519{
520	struct mips_coproc *cop0 = &vcpu->arch.cop0;
521	u32 gctl0, compare, cause;
522
523	gctl0 = read_c0_guestctl0();
524	if (gctl0 & MIPS_GCTL0_GT) {
525		/* disable guest use of hard timer */
526		write_c0_guestctl0(gctl0 & ~MIPS_GCTL0_GT);
527
528		/* save hard timer state */
529		_kvm_vz_save_htimer(vcpu, &compare, &cause);
530	} else {
531		compare = read_gc0_compare();
532		cause = read_gc0_cause();
533	}
534
535	/* save timer-related state to VCPU context */
536	kvm_write_sw_gc0_cause(cop0, cause);
537	kvm_write_sw_gc0_compare(cop0, compare);
538}
539
540/**
541 * kvm_vz_lose_htimer() - Ensure hard guest timer is not in use.
542 * @vcpu:	Virtual CPU.
543 *
544 * Transfers the state of the hard guest timer to the soft guest timer, leaving
545 * guest state intact so it can continue to be used with the soft timer.
546 */
547void kvm_vz_lose_htimer(struct kvm_vcpu *vcpu)
548{
549	u32 gctl0, compare, cause;
550
551	preempt_disable();
552	gctl0 = read_c0_guestctl0();
553	if (gctl0 & MIPS_GCTL0_GT) {
554		/* disable guest use of timer */
555		write_c0_guestctl0(gctl0 & ~MIPS_GCTL0_GT);
556
557		/* switch to soft timer */
558		_kvm_vz_save_htimer(vcpu, &compare, &cause);
559
560		/* leave soft timer in usable state */
561		_kvm_vz_restore_stimer(vcpu, compare, cause);
562	}
563	preempt_enable();
564}
565
566/**
567 * is_eva_access() - Find whether an instruction is an EVA memory accessor.
568 * @inst:	32-bit instruction encoding.
569 *
570 * Finds whether @inst encodes an EVA memory access instruction, which would
571 * indicate that emulation of it should access the user mode address space
572 * instead of the kernel mode address space. This matters for MUSUK segments
573 * which are TLB mapped for user mode but unmapped for kernel mode.
574 *
575 * Returns:	Whether @inst encodes an EVA accessor instruction.
576 */
577static bool is_eva_access(union mips_instruction inst)
578{
579	if (inst.spec3_format.opcode != spec3_op)
580		return false;
581
582	switch (inst.spec3_format.func) {
583	case lwle_op:
584	case lwre_op:
585	case cachee_op:
586	case sbe_op:
587	case she_op:
588	case sce_op:
589	case swe_op:
590	case swle_op:
591	case swre_op:
592	case prefe_op:
593	case lbue_op:
594	case lhue_op:
595	case lbe_op:
596	case lhe_op:
597	case lle_op:
598	case lwe_op:
599		return true;
600	default:
601		return false;
602	}
603}
604
605/**
606 * is_eva_am_mapped() - Find whether an access mode is mapped.
607 * @vcpu:	KVM VCPU state.
608 * @am:		3-bit encoded access mode.
609 * @eu:		Segment becomes unmapped and uncached when Status.ERL=1.
610 *
611 * Decode @am to find whether it encodes a mapped segment for the current VCPU
612 * state. Where necessary @eu and the actual instruction causing the fault are
613 * taken into account to make the decision.
614 *
615 * Returns:	Whether the VCPU faulted on a TLB mapped address.
616 */
617static bool is_eva_am_mapped(struct kvm_vcpu *vcpu, unsigned int am, bool eu)
618{
619	u32 am_lookup;
620	int err;
621
622	/*
623	 * Interpret access control mode. We assume address errors will already
624	 * have been caught by the guest, leaving us with:
625	 *      AM      UM  SM  KM  31..24 23..16
626	 * UK    0 000          Unm   0      0
627	 * MK    1 001          TLB   1
628	 * MSK   2 010      TLB TLB   1
629	 * MUSK  3 011  TLB TLB TLB   1
630	 * MUSUK 4 100  TLB TLB Unm   0      1
631	 * USK   5 101      Unm Unm   0      0
632	 * -     6 110                0      0
633	 * UUSK  7 111  Unm Unm Unm   0      0
634	 *
635	 * We shift a magic value by AM across the sign bit to find if always
636	 * TLB mapped, and if not shift by 8 again to find if it depends on KM.
637	 */
638	am_lookup = 0x70080000 << am;
639	if ((s32)am_lookup < 0) {
640		/*
641		 * MK, MSK, MUSK
642		 * Always TLB mapped, unless SegCtl.EU && ERL
643		 */
644		if (!eu || !(read_gc0_status() & ST0_ERL))
645			return true;
646	} else {
647		am_lookup <<= 8;
648		if ((s32)am_lookup < 0) {
649			union mips_instruction inst;
650			unsigned int status;
651			u32 *opc;
652
653			/*
654			 * MUSUK
655			 * TLB mapped if not in kernel mode
656			 */
657			status = read_gc0_status();
658			if (!(status & (ST0_EXL | ST0_ERL)) &&
659			    (status & ST0_KSU))
660				return true;
661			/*
662			 * EVA access instructions in kernel
663			 * mode access user address space.
664			 */
665			opc = (u32 *)vcpu->arch.pc;
666			if (vcpu->arch.host_cp0_cause & CAUSEF_BD)
667				opc += 1;
668			err = kvm_get_badinstr(opc, vcpu, &inst.word);
669			if (!err && is_eva_access(inst))
670				return true;
671		}
672	}
673
674	return false;
675}
676
677/**
678 * kvm_vz_gva_to_gpa() - Convert valid GVA to GPA.
679 * @vcpu:	KVM VCPU state.
680 * @gva:	Guest virtual address to convert.
681 * @gpa:	Output guest physical address.
682 *
683 * Convert a guest virtual address (GVA) which is valid according to the guest
684 * context, to a guest physical address (GPA).
685 *
686 * Returns:	0 on success.
687 *		-errno on failure.
688 */
689static int kvm_vz_gva_to_gpa(struct kvm_vcpu *vcpu, unsigned long gva,
690			     unsigned long *gpa)
691{
692	u32 gva32 = gva;
693	unsigned long segctl;
694
695	if ((long)gva == (s32)gva32) {
696		/* Handle canonical 32-bit virtual address */
697		if (cpu_guest_has_segments) {
698			unsigned long mask, pa;
699
700			switch (gva32 >> 29) {
701			case 0:
702			case 1: /* CFG5 (1GB) */
703				segctl = read_gc0_segctl2() >> 16;
704				mask = (unsigned long)0xfc0000000ull;
705				break;
706			case 2:
707			case 3: /* CFG4 (1GB) */
708				segctl = read_gc0_segctl2();
709				mask = (unsigned long)0xfc0000000ull;
710				break;
711			case 4: /* CFG3 (512MB) */
712				segctl = read_gc0_segctl1() >> 16;
713				mask = (unsigned long)0xfe0000000ull;
714				break;
715			case 5: /* CFG2 (512MB) */
716				segctl = read_gc0_segctl1();
717				mask = (unsigned long)0xfe0000000ull;
718				break;
719			case 6: /* CFG1 (512MB) */
720				segctl = read_gc0_segctl0() >> 16;
721				mask = (unsigned long)0xfe0000000ull;
722				break;
723			case 7: /* CFG0 (512MB) */
724				segctl = read_gc0_segctl0();
725				mask = (unsigned long)0xfe0000000ull;
726				break;
727			default:
728				/*
729				 * GCC 4.9 isn't smart enough to figure out that
730				 * segctl and mask are always initialised.
731				 */
732				unreachable();
733			}
734
735			if (is_eva_am_mapped(vcpu, (segctl >> 4) & 0x7,
736					     segctl & 0x0008))
737				goto tlb_mapped;
738
739			/* Unmapped, find guest physical address */
740			pa = (segctl << 20) & mask;
741			pa |= gva32 & ~mask;
742			*gpa = pa;
743			return 0;
744		} else if ((s32)gva32 < (s32)0xc0000000) {
745			/* legacy unmapped KSeg0 or KSeg1 */
746			*gpa = gva32 & 0x1fffffff;
747			return 0;
748		}
749#ifdef CONFIG_64BIT
750	} else if ((gva & 0xc000000000000000) == 0x8000000000000000) {
751		/* XKPHYS */
752		if (cpu_guest_has_segments) {
753			/*
754			 * Each of the 8 regions can be overridden by SegCtl2.XR
755			 * to use SegCtl1.XAM.
756			 */
757			segctl = read_gc0_segctl2();
758			if (segctl & (1ull << (56 + ((gva >> 59) & 0x7)))) {
759				segctl = read_gc0_segctl1();
760				if (is_eva_am_mapped(vcpu, (segctl >> 59) & 0x7,
761						     0))
762					goto tlb_mapped;
763			}
764
765		}
766		/*
767		 * Traditionally fully unmapped.
768		 * Bits 61:59 specify the CCA, which we can just mask off here.
769		 * Bits 58:PABITS should be zero, but we shouldn't have got here
770		 * if it wasn't.
771		 */
772		*gpa = gva & 0x07ffffffffffffff;
773		return 0;
774#endif
775	}
776
777tlb_mapped:
778	return kvm_vz_guest_tlb_lookup(vcpu, gva, gpa);
779}
780
781/**
782 * kvm_vz_badvaddr_to_gpa() - Convert GVA BadVAddr from root exception to GPA.
783 * @vcpu:	KVM VCPU state.
784 * @badvaddr:	Root BadVAddr.
785 * @gpa:	Output guest physical address.
786 *
787 * VZ implementations are permitted to report guest virtual addresses (GVA) in
788 * BadVAddr on a root exception during guest execution, instead of the more
789 * convenient guest physical addresses (GPA). When we get a GVA, this function
790 * converts it to a GPA, taking into account guest segmentation and guest TLB
791 * state.
792 *
793 * Returns:	0 on success.
794 *		-errno on failure.
795 */
796static int kvm_vz_badvaddr_to_gpa(struct kvm_vcpu *vcpu, unsigned long badvaddr,
797				  unsigned long *gpa)
798{
799	unsigned int gexccode = (vcpu->arch.host_cp0_guestctl0 &
800				 MIPS_GCTL0_GEXC) >> MIPS_GCTL0_GEXC_SHIFT;
801
802	/* If BadVAddr is GPA, then all is well in the world */
803	if (likely(gexccode == MIPS_GCTL0_GEXC_GPA)) {
804		*gpa = badvaddr;
805		return 0;
806	}
807
808	/* Otherwise we'd expect it to be GVA ... */
809	if (WARN(gexccode != MIPS_GCTL0_GEXC_GVA,
810		 "Unexpected gexccode %#x\n", gexccode))
811		return -EINVAL;
812
813	/* ... and we need to perform the GVA->GPA translation in software */
814	return kvm_vz_gva_to_gpa(vcpu, badvaddr, gpa);
815}
816
817static int kvm_trap_vz_no_handler(struct kvm_vcpu *vcpu)
818{
819	u32 *opc = (u32 *) vcpu->arch.pc;
820	u32 cause = vcpu->arch.host_cp0_cause;
821	u32 exccode = (cause & CAUSEF_EXCCODE) >> CAUSEB_EXCCODE;
822	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
823	u32 inst = 0;
824
825	/*
826	 *  Fetch the instruction.
827	 */
828	if (cause & CAUSEF_BD)
829		opc += 1;
830	kvm_get_badinstr(opc, vcpu, &inst);
831
832	kvm_err("Exception Code: %d not handled @ PC: %p, inst: 0x%08x BadVaddr: %#lx Status: %#x\n",
833		exccode, opc, inst, badvaddr,
834		read_gc0_status());
835	kvm_arch_vcpu_dump_regs(vcpu);
836	vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
837	return RESUME_HOST;
838}
839
840static unsigned long mips_process_maar(unsigned int op, unsigned long val)
841{
842	/* Mask off unused bits */
843	unsigned long mask = 0xfffff000 | MIPS_MAAR_S | MIPS_MAAR_VL;
844
845	if (read_gc0_pagegrain() & PG_ELPA)
846		mask |= 0x00ffffff00000000ull;
847	if (cpu_guest_has_mvh)
848		mask |= MIPS_MAAR_VH;
849
850	/* Set or clear VH */
851	if (op == mtc_op) {
852		/* clear VH */
853		val &= ~MIPS_MAAR_VH;
854	} else if (op == dmtc_op) {
855		/* set VH to match VL */
856		val &= ~MIPS_MAAR_VH;
857		if (val & MIPS_MAAR_VL)
858			val |= MIPS_MAAR_VH;
859	}
860
861	return val & mask;
862}
863
864static void kvm_write_maari(struct kvm_vcpu *vcpu, unsigned long val)
865{
866	struct mips_coproc *cop0 = &vcpu->arch.cop0;
867
868	val &= MIPS_MAARI_INDEX;
869	if (val == MIPS_MAARI_INDEX)
870		kvm_write_sw_gc0_maari(cop0, ARRAY_SIZE(vcpu->arch.maar) - 1);
871	else if (val < ARRAY_SIZE(vcpu->arch.maar))
872		kvm_write_sw_gc0_maari(cop0, val);
873}
874
875static enum emulation_result kvm_vz_gpsi_cop0(union mips_instruction inst,
876					      u32 *opc, u32 cause,
877					      struct kvm_vcpu *vcpu)
878{
879	struct mips_coproc *cop0 = &vcpu->arch.cop0;
880	enum emulation_result er = EMULATE_DONE;
881	u32 rt, rd, sel;
882	unsigned long curr_pc;
883	unsigned long val;
884
885	/*
886	 * Update PC and hold onto current PC in case there is
887	 * an error and we want to rollback the PC
888	 */
889	curr_pc = vcpu->arch.pc;
890	er = update_pc(vcpu, cause);
891	if (er == EMULATE_FAIL)
892		return er;
893
894	if (inst.co_format.co) {
895		switch (inst.co_format.func) {
896		case wait_op:
897			er = kvm_mips_emul_wait(vcpu);
898			break;
899		default:
900			er = EMULATE_FAIL;
901		}
902	} else {
903		rt = inst.c0r_format.rt;
904		rd = inst.c0r_format.rd;
905		sel = inst.c0r_format.sel;
906
907		switch (inst.c0r_format.rs) {
908		case dmfc_op:
909		case mfc_op:
910#ifdef CONFIG_KVM_MIPS_DEBUG_COP0_COUNTERS
911			cop0->stat[rd][sel]++;
912#endif
913			if (rd == MIPS_CP0_COUNT &&
914			    sel == 0) {			/* Count */
915				val = kvm_mips_read_count(vcpu);
916			} else if (rd == MIPS_CP0_COMPARE &&
917				   sel == 0) {		/* Compare */
918				val = read_gc0_compare();
919			} else if (rd == MIPS_CP0_LLADDR &&
920				   sel == 0) {		/* LLAddr */
921				if (cpu_guest_has_rw_llb)
922					val = read_gc0_lladdr() &
923						MIPS_LLADDR_LLB;
924				else
925					val = 0;
926			} else if (rd == MIPS_CP0_LLADDR &&
927				   sel == 1 &&		/* MAAR */
928				   cpu_guest_has_maar &&
929				   !cpu_guest_has_dyn_maar) {
930				/* MAARI must be in range */
931				BUG_ON(kvm_read_sw_gc0_maari(cop0) >=
932						ARRAY_SIZE(vcpu->arch.maar));
933				val = vcpu->arch.maar[
934					kvm_read_sw_gc0_maari(cop0)];
935			} else if ((rd == MIPS_CP0_PRID &&
936				    (sel == 0 ||	/* PRid */
937				     sel == 2 ||	/* CDMMBase */
938				     sel == 3)) ||	/* CMGCRBase */
939				   (rd == MIPS_CP0_STATUS &&
940				    (sel == 2 ||	/* SRSCtl */
941				     sel == 3)) ||	/* SRSMap */
942				   (rd == MIPS_CP0_CONFIG &&
943				    (sel == 6 ||	/* Config6 */
944				     sel == 7)) ||	/* Config7 */
945				   (rd == MIPS_CP0_LLADDR &&
946				    (sel == 2) &&	/* MAARI */
947				    cpu_guest_has_maar &&
948				    !cpu_guest_has_dyn_maar) ||
949				   (rd == MIPS_CP0_ERRCTL &&
950				    (sel == 0))) {	/* ErrCtl */
951				val = cop0->reg[rd][sel];
952#ifdef CONFIG_CPU_LOONGSON64
953			} else if (rd == MIPS_CP0_DIAG &&
954				   (sel == 0)) {	/* Diag */
955				val = cop0->reg[rd][sel];
956#endif
957			} else {
958				val = 0;
959				er = EMULATE_FAIL;
960			}
961
962			if (er != EMULATE_FAIL) {
963				/* Sign extend */
964				if (inst.c0r_format.rs == mfc_op)
965					val = (int)val;
966				vcpu->arch.gprs[rt] = val;
967			}
968
969			trace_kvm_hwr(vcpu, (inst.c0r_format.rs == mfc_op) ?
970					KVM_TRACE_MFC0 : KVM_TRACE_DMFC0,
971				      KVM_TRACE_COP0(rd, sel), val);
972			break;
973
974		case dmtc_op:
975		case mtc_op:
976#ifdef CONFIG_KVM_MIPS_DEBUG_COP0_COUNTERS
977			cop0->stat[rd][sel]++;
978#endif
979			val = vcpu->arch.gprs[rt];
980			trace_kvm_hwr(vcpu, (inst.c0r_format.rs == mtc_op) ?
981					KVM_TRACE_MTC0 : KVM_TRACE_DMTC0,
982				      KVM_TRACE_COP0(rd, sel), val);
983
984			if (rd == MIPS_CP0_COUNT &&
985			    sel == 0) {			/* Count */
986				kvm_vz_lose_htimer(vcpu);
987				kvm_mips_write_count(vcpu, vcpu->arch.gprs[rt]);
988			} else if (rd == MIPS_CP0_COMPARE &&
989				   sel == 0) {		/* Compare */
990				kvm_mips_write_compare(vcpu,
991						       vcpu->arch.gprs[rt],
992						       true);
993			} else if (rd == MIPS_CP0_LLADDR &&
994				   sel == 0) {		/* LLAddr */
995				/*
996				 * P5600 generates GPSI on guest MTC0 LLAddr.
997				 * Only allow the guest to clear LLB.
998				 */
999				if (cpu_guest_has_rw_llb &&
1000				    !(val & MIPS_LLADDR_LLB))
1001					write_gc0_lladdr(0);
1002			} else if (rd == MIPS_CP0_LLADDR &&
1003				   sel == 1 &&		/* MAAR */
1004				   cpu_guest_has_maar &&
1005				   !cpu_guest_has_dyn_maar) {
1006				val = mips_process_maar(inst.c0r_format.rs,
1007							val);
1008
1009				/* MAARI must be in range */
1010				BUG_ON(kvm_read_sw_gc0_maari(cop0) >=
1011						ARRAY_SIZE(vcpu->arch.maar));
1012				vcpu->arch.maar[kvm_read_sw_gc0_maari(cop0)] =
1013									val;
1014			} else if (rd == MIPS_CP0_LLADDR &&
1015				   (sel == 2) &&	/* MAARI */
1016				   cpu_guest_has_maar &&
1017				   !cpu_guest_has_dyn_maar) {
1018				kvm_write_maari(vcpu, val);
1019			} else if (rd == MIPS_CP0_CONFIG &&
1020				   (sel == 6)) {
1021				cop0->reg[rd][sel] = (int)val;
1022			} else if (rd == MIPS_CP0_ERRCTL &&
1023				   (sel == 0)) {	/* ErrCtl */
1024				/* ignore the written value */
1025#ifdef CONFIG_CPU_LOONGSON64
1026			} else if (rd == MIPS_CP0_DIAG &&
1027				   (sel == 0)) {	/* Diag */
1028				unsigned long flags;
1029
1030				local_irq_save(flags);
1031				if (val & LOONGSON_DIAG_BTB) {
1032					/* Flush BTB */
1033					set_c0_diag(LOONGSON_DIAG_BTB);
1034				}
1035				if (val & LOONGSON_DIAG_ITLB) {
1036					/* Flush ITLB */
1037					set_c0_diag(LOONGSON_DIAG_ITLB);
1038				}
1039				if (val & LOONGSON_DIAG_DTLB) {
1040					/* Flush DTLB */
1041					set_c0_diag(LOONGSON_DIAG_DTLB);
1042				}
1043				if (val & LOONGSON_DIAG_VTLB) {
1044					/* Flush VTLB */
1045					kvm_loongson_clear_guest_vtlb();
1046				}
1047				if (val & LOONGSON_DIAG_FTLB) {
1048					/* Flush FTLB */
1049					kvm_loongson_clear_guest_ftlb();
1050				}
1051				local_irq_restore(flags);
1052#endif
1053			} else {
1054				er = EMULATE_FAIL;
1055			}
1056			break;
1057
1058		default:
1059			er = EMULATE_FAIL;
1060			break;
1061		}
1062	}
1063	/* Rollback PC only if emulation was unsuccessful */
1064	if (er == EMULATE_FAIL) {
1065		kvm_err("[%#lx]%s: unsupported cop0 instruction 0x%08x\n",
1066			curr_pc, __func__, inst.word);
1067
1068		vcpu->arch.pc = curr_pc;
1069	}
1070
1071	return er;
1072}
1073
1074static enum emulation_result kvm_vz_gpsi_cache(union mips_instruction inst,
1075					       u32 *opc, u32 cause,
1076					       struct kvm_vcpu *vcpu)
1077{
1078	enum emulation_result er = EMULATE_DONE;
1079	u32 cache, op_inst, op, base;
1080	s16 offset;
1081	struct kvm_vcpu_arch *arch = &vcpu->arch;
1082	unsigned long va, curr_pc;
1083
1084	/*
1085	 * Update PC and hold onto current PC in case there is
1086	 * an error and we want to rollback the PC
1087	 */
1088	curr_pc = vcpu->arch.pc;
1089	er = update_pc(vcpu, cause);
1090	if (er == EMULATE_FAIL)
1091		return er;
1092
1093	base = inst.i_format.rs;
1094	op_inst = inst.i_format.rt;
1095	if (cpu_has_mips_r6)
1096		offset = inst.spec3_format.simmediate;
1097	else
1098		offset = inst.i_format.simmediate;
1099	cache = op_inst & CacheOp_Cache;
1100	op = op_inst & CacheOp_Op;
1101
1102	va = arch->gprs[base] + offset;
1103
1104	kvm_debug("CACHE (cache: %#x, op: %#x, base[%d]: %#lx, offset: %#x\n",
1105		  cache, op, base, arch->gprs[base], offset);
1106
1107	/* Secondary or tirtiary cache ops ignored */
1108	if (cache != Cache_I && cache != Cache_D)
1109		return EMULATE_DONE;
1110
1111	switch (op_inst) {
1112	case Index_Invalidate_I:
1113		flush_icache_line_indexed(va);
1114		return EMULATE_DONE;
1115	case Index_Writeback_Inv_D:
1116		flush_dcache_line_indexed(va);
1117		return EMULATE_DONE;
1118	case Hit_Invalidate_I:
1119	case Hit_Invalidate_D:
1120	case Hit_Writeback_Inv_D:
1121		if (boot_cpu_type() == CPU_CAVIUM_OCTEON3) {
1122			/* We can just flush entire icache */
1123			local_flush_icache_range(0, 0);
1124			return EMULATE_DONE;
1125		}
1126
1127		/* So far, other platforms support guest hit cache ops */
1128		break;
1129	default:
1130		break;
1131	}
1132
1133	kvm_err("@ %#lx/%#lx CACHE (cache: %#x, op: %#x, base[%d]: %#lx, offset: %#x\n",
1134		curr_pc, vcpu->arch.gprs[31], cache, op, base, arch->gprs[base],
1135		offset);
1136	/* Rollback PC */
1137	vcpu->arch.pc = curr_pc;
1138
1139	return EMULATE_FAIL;
1140}
1141
1142#ifdef CONFIG_CPU_LOONGSON64
1143static enum emulation_result kvm_vz_gpsi_lwc2(union mips_instruction inst,
1144					      u32 *opc, u32 cause,
1145					      struct kvm_vcpu *vcpu)
1146{
1147	unsigned int rs, rd;
1148	unsigned int hostcfg;
1149	unsigned long curr_pc;
1150	enum emulation_result er = EMULATE_DONE;
1151
1152	/*
1153	 * Update PC and hold onto current PC in case there is
1154	 * an error and we want to rollback the PC
1155	 */
1156	curr_pc = vcpu->arch.pc;
1157	er = update_pc(vcpu, cause);
1158	if (er == EMULATE_FAIL)
1159		return er;
1160
1161	rs = inst.loongson3_lscsr_format.rs;
1162	rd = inst.loongson3_lscsr_format.rd;
1163	switch (inst.loongson3_lscsr_format.fr) {
1164	case 0x8:  /* Read CPUCFG */
1165		++vcpu->stat.vz_cpucfg_exits;
1166		hostcfg = read_cpucfg(vcpu->arch.gprs[rs]);
1167
1168		switch (vcpu->arch.gprs[rs]) {
1169		case LOONGSON_CFG0:
1170			vcpu->arch.gprs[rd] = 0x14c000;
1171			break;
1172		case LOONGSON_CFG1:
1173			hostcfg &= (LOONGSON_CFG1_FP | LOONGSON_CFG1_MMI |
1174				    LOONGSON_CFG1_MSA1 | LOONGSON_CFG1_MSA2 |
1175				    LOONGSON_CFG1_SFBP);
1176			vcpu->arch.gprs[rd] = hostcfg;
1177			break;
1178		case LOONGSON_CFG2:
1179			hostcfg &= (LOONGSON_CFG2_LEXT1 | LOONGSON_CFG2_LEXT2 |
1180				    LOONGSON_CFG2_LEXT3 | LOONGSON_CFG2_LSPW);
1181			vcpu->arch.gprs[rd] = hostcfg;
1182			break;
1183		case LOONGSON_CFG3:
1184			vcpu->arch.gprs[rd] = hostcfg;
1185			break;
1186		default:
1187			/* Don't export any other advanced features to guest */
1188			vcpu->arch.gprs[rd] = 0;
1189			break;
1190		}
1191		break;
1192
1193	default:
1194		kvm_err("lwc2 emulate not impl %d rs %lx @%lx\n",
1195			inst.loongson3_lscsr_format.fr, vcpu->arch.gprs[rs], curr_pc);
1196		er = EMULATE_FAIL;
1197		break;
1198	}
1199
1200	/* Rollback PC only if emulation was unsuccessful */
1201	if (er == EMULATE_FAIL) {
1202		kvm_err("[%#lx]%s: unsupported lwc2 instruction 0x%08x 0x%08x\n",
1203			curr_pc, __func__, inst.word, inst.loongson3_lscsr_format.fr);
1204
1205		vcpu->arch.pc = curr_pc;
1206	}
1207
1208	return er;
1209}
1210#endif
1211
1212static enum emulation_result kvm_trap_vz_handle_gpsi(u32 cause, u32 *opc,
1213						     struct kvm_vcpu *vcpu)
1214{
1215	enum emulation_result er = EMULATE_DONE;
1216	struct kvm_vcpu_arch *arch = &vcpu->arch;
1217	union mips_instruction inst;
1218	int rd, rt, sel;
1219	int err;
1220
1221	/*
1222	 *  Fetch the instruction.
1223	 */
1224	if (cause & CAUSEF_BD)
1225		opc += 1;
1226	err = kvm_get_badinstr(opc, vcpu, &inst.word);
1227	if (err)
1228		return EMULATE_FAIL;
1229
1230	switch (inst.r_format.opcode) {
1231	case cop0_op:
1232		er = kvm_vz_gpsi_cop0(inst, opc, cause, vcpu);
1233		break;
1234#ifndef CONFIG_CPU_MIPSR6
1235	case cache_op:
1236		trace_kvm_exit(vcpu, KVM_TRACE_EXIT_CACHE);
1237		er = kvm_vz_gpsi_cache(inst, opc, cause, vcpu);
1238		break;
1239#endif
1240#ifdef CONFIG_CPU_LOONGSON64
1241	case lwc2_op:
1242		er = kvm_vz_gpsi_lwc2(inst, opc, cause, vcpu);
1243		break;
1244#endif
1245	case spec3_op:
1246		switch (inst.spec3_format.func) {
1247#ifdef CONFIG_CPU_MIPSR6
1248		case cache6_op:
1249			trace_kvm_exit(vcpu, KVM_TRACE_EXIT_CACHE);
1250			er = kvm_vz_gpsi_cache(inst, opc, cause, vcpu);
1251			break;
1252#endif
1253		case rdhwr_op:
1254			if (inst.r_format.rs || (inst.r_format.re >> 3))
1255				goto unknown;
1256
1257			rd = inst.r_format.rd;
1258			rt = inst.r_format.rt;
1259			sel = inst.r_format.re & 0x7;
1260
1261			switch (rd) {
1262			case MIPS_HWR_CC:	/* Read count register */
1263				arch->gprs[rt] =
1264					(long)(int)kvm_mips_read_count(vcpu);
1265				break;
1266			default:
1267				trace_kvm_hwr(vcpu, KVM_TRACE_RDHWR,
1268					      KVM_TRACE_HWR(rd, sel), 0);
1269				goto unknown;
1270			}
1271
1272			trace_kvm_hwr(vcpu, KVM_TRACE_RDHWR,
1273				      KVM_TRACE_HWR(rd, sel), arch->gprs[rt]);
1274
1275			er = update_pc(vcpu, cause);
1276			break;
1277		default:
1278			goto unknown;
1279		}
1280		break;
1281unknown:
1282
1283	default:
1284		kvm_err("GPSI exception not supported (%p/%#x)\n",
1285				opc, inst.word);
1286		kvm_arch_vcpu_dump_regs(vcpu);
1287		er = EMULATE_FAIL;
1288		break;
1289	}
1290
1291	return er;
1292}
1293
1294static enum emulation_result kvm_trap_vz_handle_gsfc(u32 cause, u32 *opc,
1295						     struct kvm_vcpu *vcpu)
1296{
1297	enum emulation_result er = EMULATE_DONE;
1298	struct kvm_vcpu_arch *arch = &vcpu->arch;
1299	union mips_instruction inst;
1300	int err;
1301
1302	/*
1303	 *  Fetch the instruction.
1304	 */
1305	if (cause & CAUSEF_BD)
1306		opc += 1;
1307	err = kvm_get_badinstr(opc, vcpu, &inst.word);
1308	if (err)
1309		return EMULATE_FAIL;
1310
1311	/* complete MTC0 on behalf of guest and advance EPC */
1312	if (inst.c0r_format.opcode == cop0_op &&
1313	    inst.c0r_format.rs == mtc_op &&
1314	    inst.c0r_format.z == 0) {
1315		int rt = inst.c0r_format.rt;
1316		int rd = inst.c0r_format.rd;
1317		int sel = inst.c0r_format.sel;
1318		unsigned int val = arch->gprs[rt];
1319		unsigned int old_val, change;
1320
1321		trace_kvm_hwr(vcpu, KVM_TRACE_MTC0, KVM_TRACE_COP0(rd, sel),
1322			      val);
1323
1324		if ((rd == MIPS_CP0_STATUS) && (sel == 0)) {
1325			/* FR bit should read as zero if no FPU */
1326			if (!kvm_mips_guest_has_fpu(&vcpu->arch))
1327				val &= ~(ST0_CU1 | ST0_FR);
1328
1329			/*
1330			 * Also don't allow FR to be set if host doesn't support
1331			 * it.
1332			 */
1333			if (!(boot_cpu_data.fpu_id & MIPS_FPIR_F64))
1334				val &= ~ST0_FR;
1335
1336			old_val = read_gc0_status();
1337			change = val ^ old_val;
1338
1339			if (change & ST0_FR) {
1340				/*
1341				 * FPU and Vector register state is made
1342				 * UNPREDICTABLE by a change of FR, so don't
1343				 * even bother saving it.
1344				 */
1345				kvm_drop_fpu(vcpu);
1346			}
1347
1348			/*
1349			 * If MSA state is already live, it is undefined how it
1350			 * interacts with FR=0 FPU state, and we don't want to
1351			 * hit reserved instruction exceptions trying to save
1352			 * the MSA state later when CU=1 && FR=1, so play it
1353			 * safe and save it first.
1354			 */
1355			if (change & ST0_CU1 && !(val & ST0_FR) &&
1356			    vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA)
1357				kvm_lose_fpu(vcpu);
1358
1359			write_gc0_status(val);
1360		} else if ((rd == MIPS_CP0_CAUSE) && (sel == 0)) {
1361			u32 old_cause = read_gc0_cause();
1362			u32 change = old_cause ^ val;
1363
1364			/* DC bit enabling/disabling timer? */
1365			if (change & CAUSEF_DC) {
1366				if (val & CAUSEF_DC) {
1367					kvm_vz_lose_htimer(vcpu);
1368					kvm_mips_count_disable_cause(vcpu);
1369				} else {
1370					kvm_mips_count_enable_cause(vcpu);
1371				}
1372			}
1373
1374			/* Only certain bits are RW to the guest */
1375			change &= (CAUSEF_DC | CAUSEF_IV | CAUSEF_WP |
1376				   CAUSEF_IP0 | CAUSEF_IP1);
1377
1378			/* WP can only be cleared */
1379			change &= ~CAUSEF_WP | old_cause;
1380
1381			write_gc0_cause(old_cause ^ change);
1382		} else if ((rd == MIPS_CP0_STATUS) && (sel == 1)) { /* IntCtl */
1383			write_gc0_intctl(val);
1384		} else if ((rd == MIPS_CP0_CONFIG) && (sel == 5)) {
1385			old_val = read_gc0_config5();
1386			change = val ^ old_val;
1387			/* Handle changes in FPU/MSA modes */
1388			preempt_disable();
1389
1390			/*
1391			 * Propagate FRE changes immediately if the FPU
1392			 * context is already loaded.
1393			 */
1394			if (change & MIPS_CONF5_FRE &&
1395			    vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU)
1396				change_c0_config5(MIPS_CONF5_FRE, val);
1397
1398			preempt_enable();
1399
1400			val = old_val ^
1401				(change & kvm_vz_config5_guest_wrmask(vcpu));
1402			write_gc0_config5(val);
1403		} else {
1404			kvm_err("Handle GSFC, unsupported field change @ %p: %#x\n",
1405			    opc, inst.word);
1406			er = EMULATE_FAIL;
1407		}
1408
1409		if (er != EMULATE_FAIL)
1410			er = update_pc(vcpu, cause);
1411	} else {
1412		kvm_err("Handle GSFC, unrecognized instruction @ %p: %#x\n",
1413			opc, inst.word);
1414		er = EMULATE_FAIL;
1415	}
1416
1417	return er;
1418}
1419
1420static enum emulation_result kvm_trap_vz_handle_ghfc(u32 cause, u32 *opc,
1421						     struct kvm_vcpu *vcpu)
1422{
1423	/*
1424	 * Presumably this is due to MC (guest mode change), so lets trace some
1425	 * relevant info.
1426	 */
1427	trace_kvm_guest_mode_change(vcpu);
1428
1429	return EMULATE_DONE;
1430}
1431
1432static enum emulation_result kvm_trap_vz_handle_hc(u32 cause, u32 *opc,
1433						   struct kvm_vcpu *vcpu)
1434{
1435	enum emulation_result er;
1436	union mips_instruction inst;
1437	unsigned long curr_pc;
1438	int err;
1439
1440	if (cause & CAUSEF_BD)
1441		opc += 1;
1442	err = kvm_get_badinstr(opc, vcpu, &inst.word);
1443	if (err)
1444		return EMULATE_FAIL;
1445
1446	/*
1447	 * Update PC and hold onto current PC in case there is
1448	 * an error and we want to rollback the PC
1449	 */
1450	curr_pc = vcpu->arch.pc;
1451	er = update_pc(vcpu, cause);
1452	if (er == EMULATE_FAIL)
1453		return er;
1454
1455	er = kvm_mips_emul_hypcall(vcpu, inst);
1456	if (er == EMULATE_FAIL)
1457		vcpu->arch.pc = curr_pc;
1458
1459	return er;
1460}
1461
1462static enum emulation_result kvm_trap_vz_no_handler_guest_exit(u32 gexccode,
1463							u32 cause,
1464							u32 *opc,
1465							struct kvm_vcpu *vcpu)
1466{
1467	u32 inst;
1468
1469	/*
1470	 *  Fetch the instruction.
1471	 */
1472	if (cause & CAUSEF_BD)
1473		opc += 1;
1474	kvm_get_badinstr(opc, vcpu, &inst);
1475
1476	kvm_err("Guest Exception Code: %d not yet handled @ PC: %p, inst: 0x%08x  Status: %#x\n",
1477		gexccode, opc, inst, read_gc0_status());
1478
1479	return EMULATE_FAIL;
1480}
1481
1482static int kvm_trap_vz_handle_guest_exit(struct kvm_vcpu *vcpu)
1483{
1484	u32 *opc = (u32 *) vcpu->arch.pc;
1485	u32 cause = vcpu->arch.host_cp0_cause;
1486	enum emulation_result er = EMULATE_DONE;
1487	u32 gexccode = (vcpu->arch.host_cp0_guestctl0 &
1488			MIPS_GCTL0_GEXC) >> MIPS_GCTL0_GEXC_SHIFT;
1489	int ret = RESUME_GUEST;
1490
1491	trace_kvm_exit(vcpu, KVM_TRACE_EXIT_GEXCCODE_BASE + gexccode);
1492	switch (gexccode) {
1493	case MIPS_GCTL0_GEXC_GPSI:
1494		++vcpu->stat.vz_gpsi_exits;
1495		er = kvm_trap_vz_handle_gpsi(cause, opc, vcpu);
1496		break;
1497	case MIPS_GCTL0_GEXC_GSFC:
1498		++vcpu->stat.vz_gsfc_exits;
1499		er = kvm_trap_vz_handle_gsfc(cause, opc, vcpu);
1500		break;
1501	case MIPS_GCTL0_GEXC_HC:
1502		++vcpu->stat.vz_hc_exits;
1503		er = kvm_trap_vz_handle_hc(cause, opc, vcpu);
1504		break;
1505	case MIPS_GCTL0_GEXC_GRR:
1506		++vcpu->stat.vz_grr_exits;
1507		er = kvm_trap_vz_no_handler_guest_exit(gexccode, cause, opc,
1508						       vcpu);
1509		break;
1510	case MIPS_GCTL0_GEXC_GVA:
1511		++vcpu->stat.vz_gva_exits;
1512		er = kvm_trap_vz_no_handler_guest_exit(gexccode, cause, opc,
1513						       vcpu);
1514		break;
1515	case MIPS_GCTL0_GEXC_GHFC:
1516		++vcpu->stat.vz_ghfc_exits;
1517		er = kvm_trap_vz_handle_ghfc(cause, opc, vcpu);
1518		break;
1519	case MIPS_GCTL0_GEXC_GPA:
1520		++vcpu->stat.vz_gpa_exits;
1521		er = kvm_trap_vz_no_handler_guest_exit(gexccode, cause, opc,
1522						       vcpu);
1523		break;
1524	default:
1525		++vcpu->stat.vz_resvd_exits;
1526		er = kvm_trap_vz_no_handler_guest_exit(gexccode, cause, opc,
1527						       vcpu);
1528		break;
1529
1530	}
1531
1532	if (er == EMULATE_DONE) {
1533		ret = RESUME_GUEST;
1534	} else if (er == EMULATE_HYPERCALL) {
1535		ret = kvm_mips_handle_hypcall(vcpu);
1536	} else {
1537		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1538		ret = RESUME_HOST;
1539	}
1540	return ret;
1541}
1542
1543/**
1544 * kvm_trap_vz_handle_cop_unusable() - Guest used unusable coprocessor.
1545 * @vcpu:	Virtual CPU context.
1546 *
1547 * Handle when the guest attempts to use a coprocessor which hasn't been allowed
1548 * by the root context.
1549 *
1550 * Return: value indicating whether to resume the host or the guest
1551 * 	   (RESUME_HOST or RESUME_GUEST)
1552 */
1553static int kvm_trap_vz_handle_cop_unusable(struct kvm_vcpu *vcpu)
1554{
1555	u32 cause = vcpu->arch.host_cp0_cause;
1556	enum emulation_result er = EMULATE_FAIL;
1557	int ret = RESUME_GUEST;
1558
1559	if (((cause & CAUSEF_CE) >> CAUSEB_CE) == 1) {
1560		/*
1561		 * If guest FPU not present, the FPU operation should have been
1562		 * treated as a reserved instruction!
1563		 * If FPU already in use, we shouldn't get this at all.
1564		 */
1565		if (WARN_ON(!kvm_mips_guest_has_fpu(&vcpu->arch) ||
1566			    vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU)) {
1567			preempt_enable();
1568			return EMULATE_FAIL;
1569		}
1570
1571		kvm_own_fpu(vcpu);
1572		er = EMULATE_DONE;
1573	}
1574	/* other coprocessors not handled */
1575
1576	switch (er) {
1577	case EMULATE_DONE:
1578		ret = RESUME_GUEST;
1579		break;
1580
1581	case EMULATE_FAIL:
1582		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1583		ret = RESUME_HOST;
1584		break;
1585
1586	default:
1587		BUG();
1588	}
1589	return ret;
1590}
1591
1592/**
1593 * kvm_trap_vz_handle_msa_disabled() - Guest used MSA while disabled in root.
1594 * @vcpu:	Virtual CPU context.
1595 *
1596 * Handle when the guest attempts to use MSA when it is disabled in the root
1597 * context.
1598 *
1599 * Return: value indicating whether to resume the host or the guest
1600 * 	   (RESUME_HOST or RESUME_GUEST)
1601 */
1602static int kvm_trap_vz_handle_msa_disabled(struct kvm_vcpu *vcpu)
1603{
1604	/*
1605	 * If MSA not present or not exposed to guest or FR=0, the MSA operation
1606	 * should have been treated as a reserved instruction!
1607	 * Same if CU1=1, FR=0.
1608	 * If MSA already in use, we shouldn't get this at all.
1609	 */
1610	if (!kvm_mips_guest_has_msa(&vcpu->arch) ||
1611	    (read_gc0_status() & (ST0_CU1 | ST0_FR)) == ST0_CU1 ||
1612	    !(read_gc0_config5() & MIPS_CONF5_MSAEN) ||
1613	    vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1614		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1615		return RESUME_HOST;
1616	}
1617
1618	kvm_own_msa(vcpu);
1619
1620	return RESUME_GUEST;
1621}
1622
1623static int kvm_trap_vz_handle_tlb_ld_miss(struct kvm_vcpu *vcpu)
1624{
1625	struct kvm_run *run = vcpu->run;
1626	u32 *opc = (u32 *) vcpu->arch.pc;
1627	u32 cause = vcpu->arch.host_cp0_cause;
1628	ulong badvaddr = vcpu->arch.host_cp0_badvaddr;
1629	union mips_instruction inst;
1630	enum emulation_result er = EMULATE_DONE;
1631	int err, ret = RESUME_GUEST;
1632
1633	if (kvm_mips_handle_vz_root_tlb_fault(badvaddr, vcpu, false)) {
1634		/* A code fetch fault doesn't count as an MMIO */
1635		if (kvm_is_ifetch_fault(&vcpu->arch)) {
1636			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1637			return RESUME_HOST;
1638		}
1639
1640		/* Fetch the instruction */
1641		if (cause & CAUSEF_BD)
1642			opc += 1;
1643		err = kvm_get_badinstr(opc, vcpu, &inst.word);
1644		if (err) {
1645			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1646			return RESUME_HOST;
1647		}
1648
1649		/* Treat as MMIO */
1650		er = kvm_mips_emulate_load(inst, cause, vcpu);
1651		if (er == EMULATE_FAIL) {
1652			kvm_err("Guest Emulate Load from MMIO space failed: PC: %p, BadVaddr: %#lx\n",
1653				opc, badvaddr);
1654			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1655		}
1656	}
1657
1658	if (er == EMULATE_DONE) {
1659		ret = RESUME_GUEST;
1660	} else if (er == EMULATE_DO_MMIO) {
1661		run->exit_reason = KVM_EXIT_MMIO;
1662		ret = RESUME_HOST;
1663	} else {
1664		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1665		ret = RESUME_HOST;
1666	}
1667	return ret;
1668}
1669
1670static int kvm_trap_vz_handle_tlb_st_miss(struct kvm_vcpu *vcpu)
1671{
1672	struct kvm_run *run = vcpu->run;
1673	u32 *opc = (u32 *) vcpu->arch.pc;
1674	u32 cause = vcpu->arch.host_cp0_cause;
1675	ulong badvaddr = vcpu->arch.host_cp0_badvaddr;
1676	union mips_instruction inst;
1677	enum emulation_result er = EMULATE_DONE;
1678	int err;
1679	int ret = RESUME_GUEST;
1680
1681	/* Just try the access again if we couldn't do the translation */
1682	if (kvm_vz_badvaddr_to_gpa(vcpu, badvaddr, &badvaddr))
1683		return RESUME_GUEST;
1684	vcpu->arch.host_cp0_badvaddr = badvaddr;
1685
1686	if (kvm_mips_handle_vz_root_tlb_fault(badvaddr, vcpu, true)) {
1687		/* Fetch the instruction */
1688		if (cause & CAUSEF_BD)
1689			opc += 1;
1690		err = kvm_get_badinstr(opc, vcpu, &inst.word);
1691		if (err) {
1692			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1693			return RESUME_HOST;
1694		}
1695
1696		/* Treat as MMIO */
1697		er = kvm_mips_emulate_store(inst, cause, vcpu);
1698		if (er == EMULATE_FAIL) {
1699			kvm_err("Guest Emulate Store to MMIO space failed: PC: %p, BadVaddr: %#lx\n",
1700				opc, badvaddr);
1701			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1702		}
1703	}
1704
1705	if (er == EMULATE_DONE) {
1706		ret = RESUME_GUEST;
1707	} else if (er == EMULATE_DO_MMIO) {
1708		run->exit_reason = KVM_EXIT_MMIO;
1709		ret = RESUME_HOST;
1710	} else {
1711		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1712		ret = RESUME_HOST;
1713	}
1714	return ret;
1715}
1716
1717static u64 kvm_vz_get_one_regs[] = {
1718	KVM_REG_MIPS_CP0_INDEX,
1719	KVM_REG_MIPS_CP0_ENTRYLO0,
1720	KVM_REG_MIPS_CP0_ENTRYLO1,
1721	KVM_REG_MIPS_CP0_CONTEXT,
1722	KVM_REG_MIPS_CP0_PAGEMASK,
1723	KVM_REG_MIPS_CP0_PAGEGRAIN,
1724	KVM_REG_MIPS_CP0_WIRED,
1725	KVM_REG_MIPS_CP0_HWRENA,
1726	KVM_REG_MIPS_CP0_BADVADDR,
1727	KVM_REG_MIPS_CP0_COUNT,
1728	KVM_REG_MIPS_CP0_ENTRYHI,
1729	KVM_REG_MIPS_CP0_COMPARE,
1730	KVM_REG_MIPS_CP0_STATUS,
1731	KVM_REG_MIPS_CP0_INTCTL,
1732	KVM_REG_MIPS_CP0_CAUSE,
1733	KVM_REG_MIPS_CP0_EPC,
1734	KVM_REG_MIPS_CP0_PRID,
1735	KVM_REG_MIPS_CP0_EBASE,
1736	KVM_REG_MIPS_CP0_CONFIG,
1737	KVM_REG_MIPS_CP0_CONFIG1,
1738	KVM_REG_MIPS_CP0_CONFIG2,
1739	KVM_REG_MIPS_CP0_CONFIG3,
1740	KVM_REG_MIPS_CP0_CONFIG4,
1741	KVM_REG_MIPS_CP0_CONFIG5,
1742	KVM_REG_MIPS_CP0_CONFIG6,
1743#ifdef CONFIG_64BIT
1744	KVM_REG_MIPS_CP0_XCONTEXT,
1745#endif
1746	KVM_REG_MIPS_CP0_ERROREPC,
1747
1748	KVM_REG_MIPS_COUNT_CTL,
1749	KVM_REG_MIPS_COUNT_RESUME,
1750	KVM_REG_MIPS_COUNT_HZ,
1751};
1752
1753static u64 kvm_vz_get_one_regs_contextconfig[] = {
1754	KVM_REG_MIPS_CP0_CONTEXTCONFIG,
1755#ifdef CONFIG_64BIT
1756	KVM_REG_MIPS_CP0_XCONTEXTCONFIG,
1757#endif
1758};
1759
1760static u64 kvm_vz_get_one_regs_segments[] = {
1761	KVM_REG_MIPS_CP0_SEGCTL0,
1762	KVM_REG_MIPS_CP0_SEGCTL1,
1763	KVM_REG_MIPS_CP0_SEGCTL2,
1764};
1765
1766static u64 kvm_vz_get_one_regs_htw[] = {
1767	KVM_REG_MIPS_CP0_PWBASE,
1768	KVM_REG_MIPS_CP0_PWFIELD,
1769	KVM_REG_MIPS_CP0_PWSIZE,
1770	KVM_REG_MIPS_CP0_PWCTL,
1771};
1772
1773static u64 kvm_vz_get_one_regs_kscratch[] = {
1774	KVM_REG_MIPS_CP0_KSCRATCH1,
1775	KVM_REG_MIPS_CP0_KSCRATCH2,
1776	KVM_REG_MIPS_CP0_KSCRATCH3,
1777	KVM_REG_MIPS_CP0_KSCRATCH4,
1778	KVM_REG_MIPS_CP0_KSCRATCH5,
1779	KVM_REG_MIPS_CP0_KSCRATCH6,
1780};
1781
1782static unsigned long kvm_vz_num_regs(struct kvm_vcpu *vcpu)
1783{
1784	unsigned long ret;
1785
1786	ret = ARRAY_SIZE(kvm_vz_get_one_regs);
1787	if (cpu_guest_has_userlocal)
1788		++ret;
1789	if (cpu_guest_has_badinstr)
1790		++ret;
1791	if (cpu_guest_has_badinstrp)
1792		++ret;
1793	if (cpu_guest_has_contextconfig)
1794		ret += ARRAY_SIZE(kvm_vz_get_one_regs_contextconfig);
1795	if (cpu_guest_has_segments)
1796		ret += ARRAY_SIZE(kvm_vz_get_one_regs_segments);
1797	if (cpu_guest_has_htw || cpu_guest_has_ldpte)
1798		ret += ARRAY_SIZE(kvm_vz_get_one_regs_htw);
1799	if (cpu_guest_has_maar && !cpu_guest_has_dyn_maar)
1800		ret += 1 + ARRAY_SIZE(vcpu->arch.maar);
1801	ret += __arch_hweight8(cpu_data[0].guest.kscratch_mask);
1802
1803	return ret;
1804}
1805
1806static int kvm_vz_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices)
1807{
1808	u64 index;
1809	unsigned int i;
1810
1811	if (copy_to_user(indices, kvm_vz_get_one_regs,
1812			 sizeof(kvm_vz_get_one_regs)))
1813		return -EFAULT;
1814	indices += ARRAY_SIZE(kvm_vz_get_one_regs);
1815
1816	if (cpu_guest_has_userlocal) {
1817		index = KVM_REG_MIPS_CP0_USERLOCAL;
1818		if (copy_to_user(indices, &index, sizeof(index)))
1819			return -EFAULT;
1820		++indices;
1821	}
1822	if (cpu_guest_has_badinstr) {
1823		index = KVM_REG_MIPS_CP0_BADINSTR;
1824		if (copy_to_user(indices, &index, sizeof(index)))
1825			return -EFAULT;
1826		++indices;
1827	}
1828	if (cpu_guest_has_badinstrp) {
1829		index = KVM_REG_MIPS_CP0_BADINSTRP;
1830		if (copy_to_user(indices, &index, sizeof(index)))
1831			return -EFAULT;
1832		++indices;
1833	}
1834	if (cpu_guest_has_contextconfig) {
1835		if (copy_to_user(indices, kvm_vz_get_one_regs_contextconfig,
1836				 sizeof(kvm_vz_get_one_regs_contextconfig)))
1837			return -EFAULT;
1838		indices += ARRAY_SIZE(kvm_vz_get_one_regs_contextconfig);
1839	}
1840	if (cpu_guest_has_segments) {
1841		if (copy_to_user(indices, kvm_vz_get_one_regs_segments,
1842				 sizeof(kvm_vz_get_one_regs_segments)))
1843			return -EFAULT;
1844		indices += ARRAY_SIZE(kvm_vz_get_one_regs_segments);
1845	}
1846	if (cpu_guest_has_htw || cpu_guest_has_ldpte) {
1847		if (copy_to_user(indices, kvm_vz_get_one_regs_htw,
1848				 sizeof(kvm_vz_get_one_regs_htw)))
1849			return -EFAULT;
1850		indices += ARRAY_SIZE(kvm_vz_get_one_regs_htw);
1851	}
1852	if (cpu_guest_has_maar && !cpu_guest_has_dyn_maar) {
1853		for (i = 0; i < ARRAY_SIZE(vcpu->arch.maar); ++i) {
1854			index = KVM_REG_MIPS_CP0_MAAR(i);
1855			if (copy_to_user(indices, &index, sizeof(index)))
1856				return -EFAULT;
1857			++indices;
1858		}
1859
1860		index = KVM_REG_MIPS_CP0_MAARI;
1861		if (copy_to_user(indices, &index, sizeof(index)))
1862			return -EFAULT;
1863		++indices;
1864	}
1865	for (i = 0; i < 6; ++i) {
1866		if (!cpu_guest_has_kscr(i + 2))
1867			continue;
1868
1869		if (copy_to_user(indices, &kvm_vz_get_one_regs_kscratch[i],
1870				 sizeof(kvm_vz_get_one_regs_kscratch[i])))
1871			return -EFAULT;
1872		++indices;
1873	}
1874
1875	return 0;
1876}
1877
1878static inline s64 entrylo_kvm_to_user(unsigned long v)
1879{
1880	s64 mask, ret = v;
1881
1882	if (BITS_PER_LONG == 32) {
1883		/*
1884		 * KVM API exposes 64-bit version of the register, so move the
1885		 * RI/XI bits up into place.
1886		 */
1887		mask = MIPS_ENTRYLO_RI | MIPS_ENTRYLO_XI;
1888		ret &= ~mask;
1889		ret |= ((s64)v & mask) << 32;
1890	}
1891	return ret;
1892}
1893
1894static inline unsigned long entrylo_user_to_kvm(s64 v)
1895{
1896	unsigned long mask, ret = v;
1897
1898	if (BITS_PER_LONG == 32) {
1899		/*
1900		 * KVM API exposes 64-bit versiono of the register, so move the
1901		 * RI/XI bits down into place.
1902		 */
1903		mask = MIPS_ENTRYLO_RI | MIPS_ENTRYLO_XI;
1904		ret &= ~mask;
1905		ret |= (v >> 32) & mask;
1906	}
1907	return ret;
1908}
1909
1910static int kvm_vz_get_one_reg(struct kvm_vcpu *vcpu,
1911			      const struct kvm_one_reg *reg,
1912			      s64 *v)
1913{
1914	struct mips_coproc *cop0 = &vcpu->arch.cop0;
1915	unsigned int idx;
1916
1917	switch (reg->id) {
1918	case KVM_REG_MIPS_CP0_INDEX:
1919		*v = (long)read_gc0_index();
1920		break;
1921	case KVM_REG_MIPS_CP0_ENTRYLO0:
1922		*v = entrylo_kvm_to_user(read_gc0_entrylo0());
1923		break;
1924	case KVM_REG_MIPS_CP0_ENTRYLO1:
1925		*v = entrylo_kvm_to_user(read_gc0_entrylo1());
1926		break;
1927	case KVM_REG_MIPS_CP0_CONTEXT:
1928		*v = (long)read_gc0_context();
1929		break;
1930	case KVM_REG_MIPS_CP0_CONTEXTCONFIG:
1931		if (!cpu_guest_has_contextconfig)
1932			return -EINVAL;
1933		*v = read_gc0_contextconfig();
1934		break;
1935	case KVM_REG_MIPS_CP0_USERLOCAL:
1936		if (!cpu_guest_has_userlocal)
1937			return -EINVAL;
1938		*v = read_gc0_userlocal();
1939		break;
1940#ifdef CONFIG_64BIT
1941	case KVM_REG_MIPS_CP0_XCONTEXTCONFIG:
1942		if (!cpu_guest_has_contextconfig)
1943			return -EINVAL;
1944		*v = read_gc0_xcontextconfig();
1945		break;
1946#endif
1947	case KVM_REG_MIPS_CP0_PAGEMASK:
1948		*v = (long)read_gc0_pagemask();
1949		break;
1950	case KVM_REG_MIPS_CP0_PAGEGRAIN:
1951		*v = (long)read_gc0_pagegrain();
1952		break;
1953	case KVM_REG_MIPS_CP0_SEGCTL0:
1954		if (!cpu_guest_has_segments)
1955			return -EINVAL;
1956		*v = read_gc0_segctl0();
1957		break;
1958	case KVM_REG_MIPS_CP0_SEGCTL1:
1959		if (!cpu_guest_has_segments)
1960			return -EINVAL;
1961		*v = read_gc0_segctl1();
1962		break;
1963	case KVM_REG_MIPS_CP0_SEGCTL2:
1964		if (!cpu_guest_has_segments)
1965			return -EINVAL;
1966		*v = read_gc0_segctl2();
1967		break;
1968	case KVM_REG_MIPS_CP0_PWBASE:
1969		if (!cpu_guest_has_htw && !cpu_guest_has_ldpte)
1970			return -EINVAL;
1971		*v = read_gc0_pwbase();
1972		break;
1973	case KVM_REG_MIPS_CP0_PWFIELD:
1974		if (!cpu_guest_has_htw && !cpu_guest_has_ldpte)
1975			return -EINVAL;
1976		*v = read_gc0_pwfield();
1977		break;
1978	case KVM_REG_MIPS_CP0_PWSIZE:
1979		if (!cpu_guest_has_htw && !cpu_guest_has_ldpte)
1980			return -EINVAL;
1981		*v = read_gc0_pwsize();
1982		break;
1983	case KVM_REG_MIPS_CP0_WIRED:
1984		*v = (long)read_gc0_wired();
1985		break;
1986	case KVM_REG_MIPS_CP0_PWCTL:
1987		if (!cpu_guest_has_htw && !cpu_guest_has_ldpte)
1988			return -EINVAL;
1989		*v = read_gc0_pwctl();
1990		break;
1991	case KVM_REG_MIPS_CP0_HWRENA:
1992		*v = (long)read_gc0_hwrena();
1993		break;
1994	case KVM_REG_MIPS_CP0_BADVADDR:
1995		*v = (long)read_gc0_badvaddr();
1996		break;
1997	case KVM_REG_MIPS_CP0_BADINSTR:
1998		if (!cpu_guest_has_badinstr)
1999			return -EINVAL;
2000		*v = read_gc0_badinstr();
2001		break;
2002	case KVM_REG_MIPS_CP0_BADINSTRP:
2003		if (!cpu_guest_has_badinstrp)
2004			return -EINVAL;
2005		*v = read_gc0_badinstrp();
2006		break;
2007	case KVM_REG_MIPS_CP0_COUNT:
2008		*v = kvm_mips_read_count(vcpu);
2009		break;
2010	case KVM_REG_MIPS_CP0_ENTRYHI:
2011		*v = (long)read_gc0_entryhi();
2012		break;
2013	case KVM_REG_MIPS_CP0_COMPARE:
2014		*v = (long)read_gc0_compare();
2015		break;
2016	case KVM_REG_MIPS_CP0_STATUS:
2017		*v = (long)read_gc0_status();
2018		break;
2019	case KVM_REG_MIPS_CP0_INTCTL:
2020		*v = read_gc0_intctl();
2021		break;
2022	case KVM_REG_MIPS_CP0_CAUSE:
2023		*v = (long)read_gc0_cause();
2024		break;
2025	case KVM_REG_MIPS_CP0_EPC:
2026		*v = (long)read_gc0_epc();
2027		break;
2028	case KVM_REG_MIPS_CP0_PRID:
2029		switch (boot_cpu_type()) {
2030		case CPU_CAVIUM_OCTEON3:
2031			/* Octeon III has a read-only guest.PRid */
2032			*v = read_gc0_prid();
2033			break;
2034		default:
2035			*v = (long)kvm_read_c0_guest_prid(cop0);
2036			break;
2037		}
2038		break;
2039	case KVM_REG_MIPS_CP0_EBASE:
2040		*v = kvm_vz_read_gc0_ebase();
2041		break;
2042	case KVM_REG_MIPS_CP0_CONFIG:
2043		*v = read_gc0_config();
2044		break;
2045	case KVM_REG_MIPS_CP0_CONFIG1:
2046		if (!cpu_guest_has_conf1)
2047			return -EINVAL;
2048		*v = read_gc0_config1();
2049		break;
2050	case KVM_REG_MIPS_CP0_CONFIG2:
2051		if (!cpu_guest_has_conf2)
2052			return -EINVAL;
2053		*v = read_gc0_config2();
2054		break;
2055	case KVM_REG_MIPS_CP0_CONFIG3:
2056		if (!cpu_guest_has_conf3)
2057			return -EINVAL;
2058		*v = read_gc0_config3();
2059		break;
2060	case KVM_REG_MIPS_CP0_CONFIG4:
2061		if (!cpu_guest_has_conf4)
2062			return -EINVAL;
2063		*v = read_gc0_config4();
2064		break;
2065	case KVM_REG_MIPS_CP0_CONFIG5:
2066		if (!cpu_guest_has_conf5)
2067			return -EINVAL;
2068		*v = read_gc0_config5();
2069		break;
2070	case KVM_REG_MIPS_CP0_CONFIG6:
2071		*v = kvm_read_sw_gc0_config6(cop0);
2072		break;
2073	case KVM_REG_MIPS_CP0_MAAR(0) ... KVM_REG_MIPS_CP0_MAAR(0x3f):
2074		if (!cpu_guest_has_maar || cpu_guest_has_dyn_maar)
2075			return -EINVAL;
2076		idx = reg->id - KVM_REG_MIPS_CP0_MAAR(0);
2077		if (idx >= ARRAY_SIZE(vcpu->arch.maar))
2078			return -EINVAL;
2079		*v = vcpu->arch.maar[idx];
2080		break;
2081	case KVM_REG_MIPS_CP0_MAARI:
2082		if (!cpu_guest_has_maar || cpu_guest_has_dyn_maar)
2083			return -EINVAL;
2084		*v = kvm_read_sw_gc0_maari(&vcpu->arch.cop0);
2085		break;
2086#ifdef CONFIG_64BIT
2087	case KVM_REG_MIPS_CP0_XCONTEXT:
2088		*v = read_gc0_xcontext();
2089		break;
2090#endif
2091	case KVM_REG_MIPS_CP0_ERROREPC:
2092		*v = (long)read_gc0_errorepc();
2093		break;
2094	case KVM_REG_MIPS_CP0_KSCRATCH1 ... KVM_REG_MIPS_CP0_KSCRATCH6:
2095		idx = reg->id - KVM_REG_MIPS_CP0_KSCRATCH1 + 2;
2096		if (!cpu_guest_has_kscr(idx))
2097			return -EINVAL;
2098		switch (idx) {
2099		case 2:
2100			*v = (long)read_gc0_kscratch1();
2101			break;
2102		case 3:
2103			*v = (long)read_gc0_kscratch2();
2104			break;
2105		case 4:
2106			*v = (long)read_gc0_kscratch3();
2107			break;
2108		case 5:
2109			*v = (long)read_gc0_kscratch4();
2110			break;
2111		case 6:
2112			*v = (long)read_gc0_kscratch5();
2113			break;
2114		case 7:
2115			*v = (long)read_gc0_kscratch6();
2116			break;
2117		}
2118		break;
2119	case KVM_REG_MIPS_COUNT_CTL:
2120		*v = vcpu->arch.count_ctl;
2121		break;
2122	case KVM_REG_MIPS_COUNT_RESUME:
2123		*v = ktime_to_ns(vcpu->arch.count_resume);
2124		break;
2125	case KVM_REG_MIPS_COUNT_HZ:
2126		*v = vcpu->arch.count_hz;
2127		break;
2128	default:
2129		return -EINVAL;
2130	}
2131	return 0;
2132}
2133
2134static int kvm_vz_set_one_reg(struct kvm_vcpu *vcpu,
2135			      const struct kvm_one_reg *reg,
2136			      s64 v)
2137{
2138	struct mips_coproc *cop0 = &vcpu->arch.cop0;
2139	unsigned int idx;
2140	int ret = 0;
2141	unsigned int cur, change;
2142
2143	switch (reg->id) {
2144	case KVM_REG_MIPS_CP0_INDEX:
2145		write_gc0_index(v);
2146		break;
2147	case KVM_REG_MIPS_CP0_ENTRYLO0:
2148		write_gc0_entrylo0(entrylo_user_to_kvm(v));
2149		break;
2150	case KVM_REG_MIPS_CP0_ENTRYLO1:
2151		write_gc0_entrylo1(entrylo_user_to_kvm(v));
2152		break;
2153	case KVM_REG_MIPS_CP0_CONTEXT:
2154		write_gc0_context(v);
2155		break;
2156	case KVM_REG_MIPS_CP0_CONTEXTCONFIG:
2157		if (!cpu_guest_has_contextconfig)
2158			return -EINVAL;
2159		write_gc0_contextconfig(v);
2160		break;
2161	case KVM_REG_MIPS_CP0_USERLOCAL:
2162		if (!cpu_guest_has_userlocal)
2163			return -EINVAL;
2164		write_gc0_userlocal(v);
2165		break;
2166#ifdef CONFIG_64BIT
2167	case KVM_REG_MIPS_CP0_XCONTEXTCONFIG:
2168		if (!cpu_guest_has_contextconfig)
2169			return -EINVAL;
2170		write_gc0_xcontextconfig(v);
2171		break;
2172#endif
2173	case KVM_REG_MIPS_CP0_PAGEMASK:
2174		write_gc0_pagemask(v);
2175		break;
2176	case KVM_REG_MIPS_CP0_PAGEGRAIN:
2177		write_gc0_pagegrain(v);
2178		break;
2179	case KVM_REG_MIPS_CP0_SEGCTL0:
2180		if (!cpu_guest_has_segments)
2181			return -EINVAL;
2182		write_gc0_segctl0(v);
2183		break;
2184	case KVM_REG_MIPS_CP0_SEGCTL1:
2185		if (!cpu_guest_has_segments)
2186			return -EINVAL;
2187		write_gc0_segctl1(v);
2188		break;
2189	case KVM_REG_MIPS_CP0_SEGCTL2:
2190		if (!cpu_guest_has_segments)
2191			return -EINVAL;
2192		write_gc0_segctl2(v);
2193		break;
2194	case KVM_REG_MIPS_CP0_PWBASE:
2195		if (!cpu_guest_has_htw && !cpu_guest_has_ldpte)
2196			return -EINVAL;
2197		write_gc0_pwbase(v);
2198		break;
2199	case KVM_REG_MIPS_CP0_PWFIELD:
2200		if (!cpu_guest_has_htw && !cpu_guest_has_ldpte)
2201			return -EINVAL;
2202		write_gc0_pwfield(v);
2203		break;
2204	case KVM_REG_MIPS_CP0_PWSIZE:
2205		if (!cpu_guest_has_htw && !cpu_guest_has_ldpte)
2206			return -EINVAL;
2207		write_gc0_pwsize(v);
2208		break;
2209	case KVM_REG_MIPS_CP0_WIRED:
2210		change_gc0_wired(MIPSR6_WIRED_WIRED, v);
2211		break;
2212	case KVM_REG_MIPS_CP0_PWCTL:
2213		if (!cpu_guest_has_htw && !cpu_guest_has_ldpte)
2214			return -EINVAL;
2215		write_gc0_pwctl(v);
2216		break;
2217	case KVM_REG_MIPS_CP0_HWRENA:
2218		write_gc0_hwrena(v);
2219		break;
2220	case KVM_REG_MIPS_CP0_BADVADDR:
2221		write_gc0_badvaddr(v);
2222		break;
2223	case KVM_REG_MIPS_CP0_BADINSTR:
2224		if (!cpu_guest_has_badinstr)
2225			return -EINVAL;
2226		write_gc0_badinstr(v);
2227		break;
2228	case KVM_REG_MIPS_CP0_BADINSTRP:
2229		if (!cpu_guest_has_badinstrp)
2230			return -EINVAL;
2231		write_gc0_badinstrp(v);
2232		break;
2233	case KVM_REG_MIPS_CP0_COUNT:
2234		kvm_mips_write_count(vcpu, v);
2235		break;
2236	case KVM_REG_MIPS_CP0_ENTRYHI:
2237		write_gc0_entryhi(v);
2238		break;
2239	case KVM_REG_MIPS_CP0_COMPARE:
2240		kvm_mips_write_compare(vcpu, v, false);
2241		break;
2242	case KVM_REG_MIPS_CP0_STATUS:
2243		write_gc0_status(v);
2244		break;
2245	case KVM_REG_MIPS_CP0_INTCTL:
2246		write_gc0_intctl(v);
2247		break;
2248	case KVM_REG_MIPS_CP0_CAUSE:
2249		/*
2250		 * If the timer is stopped or started (DC bit) it must look
2251		 * atomic with changes to the timer interrupt pending bit (TI).
2252		 * A timer interrupt should not happen in between.
2253		 */
2254		if ((read_gc0_cause() ^ v) & CAUSEF_DC) {
2255			if (v & CAUSEF_DC) {
2256				/* disable timer first */
2257				kvm_mips_count_disable_cause(vcpu);
2258				change_gc0_cause((u32)~CAUSEF_DC, v);
2259			} else {
2260				/* enable timer last */
2261				change_gc0_cause((u32)~CAUSEF_DC, v);
2262				kvm_mips_count_enable_cause(vcpu);
2263			}
2264		} else {
2265			write_gc0_cause(v);
2266		}
2267		break;
2268	case KVM_REG_MIPS_CP0_EPC:
2269		write_gc0_epc(v);
2270		break;
2271	case KVM_REG_MIPS_CP0_PRID:
2272		switch (boot_cpu_type()) {
2273		case CPU_CAVIUM_OCTEON3:
2274			/* Octeon III has a guest.PRid, but its read-only */
2275			break;
2276		default:
2277			kvm_write_c0_guest_prid(cop0, v);
2278			break;
2279		}
2280		break;
2281	case KVM_REG_MIPS_CP0_EBASE:
2282		kvm_vz_write_gc0_ebase(v);
2283		break;
2284	case KVM_REG_MIPS_CP0_CONFIG:
2285		cur = read_gc0_config();
2286		change = (cur ^ v) & kvm_vz_config_user_wrmask(vcpu);
2287		if (change) {
2288			v = cur ^ change;
2289			write_gc0_config(v);
2290		}
2291		break;
2292	case KVM_REG_MIPS_CP0_CONFIG1:
2293		if (!cpu_guest_has_conf1)
2294			break;
2295		cur = read_gc0_config1();
2296		change = (cur ^ v) & kvm_vz_config1_user_wrmask(vcpu);
2297		if (change) {
2298			v = cur ^ change;
2299			write_gc0_config1(v);
2300		}
2301		break;
2302	case KVM_REG_MIPS_CP0_CONFIG2:
2303		if (!cpu_guest_has_conf2)
2304			break;
2305		cur = read_gc0_config2();
2306		change = (cur ^ v) & kvm_vz_config2_user_wrmask(vcpu);
2307		if (change) {
2308			v = cur ^ change;
2309			write_gc0_config2(v);
2310		}
2311		break;
2312	case KVM_REG_MIPS_CP0_CONFIG3:
2313		if (!cpu_guest_has_conf3)
2314			break;
2315		cur = read_gc0_config3();
2316		change = (cur ^ v) & kvm_vz_config3_user_wrmask(vcpu);
2317		if (change) {
2318			v = cur ^ change;
2319			write_gc0_config3(v);
2320		}
2321		break;
2322	case KVM_REG_MIPS_CP0_CONFIG4:
2323		if (!cpu_guest_has_conf4)
2324			break;
2325		cur = read_gc0_config4();
2326		change = (cur ^ v) & kvm_vz_config4_user_wrmask(vcpu);
2327		if (change) {
2328			v = cur ^ change;
2329			write_gc0_config4(v);
2330		}
2331		break;
2332	case KVM_REG_MIPS_CP0_CONFIG5:
2333		if (!cpu_guest_has_conf5)
2334			break;
2335		cur = read_gc0_config5();
2336		change = (cur ^ v) & kvm_vz_config5_user_wrmask(vcpu);
2337		if (change) {
2338			v = cur ^ change;
2339			write_gc0_config5(v);
2340		}
2341		break;
2342	case KVM_REG_MIPS_CP0_CONFIG6:
2343		cur = kvm_read_sw_gc0_config6(cop0);
2344		change = (cur ^ v) & kvm_vz_config6_user_wrmask(vcpu);
2345		if (change) {
2346			v = cur ^ change;
2347			kvm_write_sw_gc0_config6(cop0, (int)v);
2348		}
2349		break;
2350	case KVM_REG_MIPS_CP0_MAAR(0) ... KVM_REG_MIPS_CP0_MAAR(0x3f):
2351		if (!cpu_guest_has_maar || cpu_guest_has_dyn_maar)
2352			return -EINVAL;
2353		idx = reg->id - KVM_REG_MIPS_CP0_MAAR(0);
2354		if (idx >= ARRAY_SIZE(vcpu->arch.maar))
2355			return -EINVAL;
2356		vcpu->arch.maar[idx] = mips_process_maar(dmtc_op, v);
2357		break;
2358	case KVM_REG_MIPS_CP0_MAARI:
2359		if (!cpu_guest_has_maar || cpu_guest_has_dyn_maar)
2360			return -EINVAL;
2361		kvm_write_maari(vcpu, v);
2362		break;
2363#ifdef CONFIG_64BIT
2364	case KVM_REG_MIPS_CP0_XCONTEXT:
2365		write_gc0_xcontext(v);
2366		break;
2367#endif
2368	case KVM_REG_MIPS_CP0_ERROREPC:
2369		write_gc0_errorepc(v);
2370		break;
2371	case KVM_REG_MIPS_CP0_KSCRATCH1 ... KVM_REG_MIPS_CP0_KSCRATCH6:
2372		idx = reg->id - KVM_REG_MIPS_CP0_KSCRATCH1 + 2;
2373		if (!cpu_guest_has_kscr(idx))
2374			return -EINVAL;
2375		switch (idx) {
2376		case 2:
2377			write_gc0_kscratch1(v);
2378			break;
2379		case 3:
2380			write_gc0_kscratch2(v);
2381			break;
2382		case 4:
2383			write_gc0_kscratch3(v);
2384			break;
2385		case 5:
2386			write_gc0_kscratch4(v);
2387			break;
2388		case 6:
2389			write_gc0_kscratch5(v);
2390			break;
2391		case 7:
2392			write_gc0_kscratch6(v);
2393			break;
2394		}
2395		break;
2396	case KVM_REG_MIPS_COUNT_CTL:
2397		ret = kvm_mips_set_count_ctl(vcpu, v);
2398		break;
2399	case KVM_REG_MIPS_COUNT_RESUME:
2400		ret = kvm_mips_set_count_resume(vcpu, v);
2401		break;
2402	case KVM_REG_MIPS_COUNT_HZ:
2403		ret = kvm_mips_set_count_hz(vcpu, v);
2404		break;
2405	default:
2406		return -EINVAL;
2407	}
2408	return ret;
2409}
2410
2411#define guestid_cache(cpu)	(cpu_data[cpu].guestid_cache)
2412static void kvm_vz_get_new_guestid(unsigned long cpu, struct kvm_vcpu *vcpu)
2413{
2414	unsigned long guestid = guestid_cache(cpu);
2415
2416	if (!(++guestid & GUESTID_MASK)) {
2417		if (cpu_has_vtag_icache)
2418			flush_icache_all();
2419
2420		if (!guestid)		/* fix version if needed */
2421			guestid = GUESTID_FIRST_VERSION;
2422
2423		++guestid;		/* guestid 0 reserved for root */
2424
2425		/* start new guestid cycle */
2426		kvm_vz_local_flush_roottlb_all_guests();
2427		kvm_vz_local_flush_guesttlb_all();
2428	}
2429
2430	guestid_cache(cpu) = guestid;
2431}
2432
2433/* Returns 1 if the guest TLB may be clobbered */
2434static int kvm_vz_check_requests(struct kvm_vcpu *vcpu, int cpu)
2435{
2436	int ret = 0;
2437	int i;
2438
2439	if (!kvm_request_pending(vcpu))
2440		return 0;
2441
2442	if (kvm_check_request(KVM_REQ_TLB_FLUSH, vcpu)) {
2443		if (cpu_has_guestid) {
2444			/* Drop all GuestIDs for this VCPU */
2445			for_each_possible_cpu(i)
2446				vcpu->arch.vzguestid[i] = 0;
2447			/* This will clobber guest TLB contents too */
2448			ret = 1;
2449		}
2450		/*
2451		 * For Root ASID Dealias (RAD) we don't do anything here, but we
2452		 * still need the request to ensure we recheck asid_flush_mask.
2453		 * We can still return 0 as only the root TLB will be affected
2454		 * by a root ASID flush.
2455		 */
2456	}
2457
2458	return ret;
2459}
2460
2461static void kvm_vz_vcpu_save_wired(struct kvm_vcpu *vcpu)
2462{
2463	unsigned int wired = read_gc0_wired();
2464	struct kvm_mips_tlb *tlbs;
2465	int i;
2466
2467	/* Expand the wired TLB array if necessary */
2468	wired &= MIPSR6_WIRED_WIRED;
2469	if (wired > vcpu->arch.wired_tlb_limit) {
2470		tlbs = krealloc(vcpu->arch.wired_tlb, wired *
2471				sizeof(*vcpu->arch.wired_tlb), GFP_ATOMIC);
2472		if (WARN_ON(!tlbs)) {
2473			/* Save whatever we can */
2474			wired = vcpu->arch.wired_tlb_limit;
2475		} else {
2476			vcpu->arch.wired_tlb = tlbs;
2477			vcpu->arch.wired_tlb_limit = wired;
2478		}
2479	}
2480
2481	if (wired)
2482		/* Save wired entries from the guest TLB */
2483		kvm_vz_save_guesttlb(vcpu->arch.wired_tlb, 0, wired);
2484	/* Invalidate any dropped entries since last time */
2485	for (i = wired; i < vcpu->arch.wired_tlb_used; ++i) {
2486		vcpu->arch.wired_tlb[i].tlb_hi = UNIQUE_GUEST_ENTRYHI(i);
2487		vcpu->arch.wired_tlb[i].tlb_lo[0] = 0;
2488		vcpu->arch.wired_tlb[i].tlb_lo[1] = 0;
2489		vcpu->arch.wired_tlb[i].tlb_mask = 0;
2490	}
2491	vcpu->arch.wired_tlb_used = wired;
2492}
2493
2494static void kvm_vz_vcpu_load_wired(struct kvm_vcpu *vcpu)
2495{
2496	/* Load wired entries into the guest TLB */
2497	if (vcpu->arch.wired_tlb)
2498		kvm_vz_load_guesttlb(vcpu->arch.wired_tlb, 0,
2499				     vcpu->arch.wired_tlb_used);
2500}
2501
2502static void kvm_vz_vcpu_load_tlb(struct kvm_vcpu *vcpu, int cpu)
2503{
2504	struct kvm *kvm = vcpu->kvm;
2505	struct mm_struct *gpa_mm = &kvm->arch.gpa_mm;
2506	bool migrated;
2507
2508	/*
2509	 * Are we entering guest context on a different CPU to last time?
2510	 * If so, the VCPU's guest TLB state on this CPU may be stale.
2511	 */
2512	migrated = (vcpu->arch.last_exec_cpu != cpu);
2513	vcpu->arch.last_exec_cpu = cpu;
2514
2515	/*
2516	 * A vcpu's GuestID is set in GuestCtl1.ID when the vcpu is loaded and
2517	 * remains set until another vcpu is loaded in.  As a rule GuestRID
2518	 * remains zeroed when in root context unless the kernel is busy
2519	 * manipulating guest tlb entries.
2520	 */
2521	if (cpu_has_guestid) {
2522		/*
2523		 * Check if our GuestID is of an older version and thus invalid.
2524		 *
2525		 * We also discard the stored GuestID if we've executed on
2526		 * another CPU, as the guest mappings may have changed without
2527		 * hypervisor knowledge.
2528		 */
2529		if (migrated ||
2530		    (vcpu->arch.vzguestid[cpu] ^ guestid_cache(cpu)) &
2531					GUESTID_VERSION_MASK) {
2532			kvm_vz_get_new_guestid(cpu, vcpu);
2533			vcpu->arch.vzguestid[cpu] = guestid_cache(cpu);
2534			trace_kvm_guestid_change(vcpu,
2535						 vcpu->arch.vzguestid[cpu]);
2536		}
2537
2538		/* Restore GuestID */
2539		change_c0_guestctl1(GUESTID_MASK, vcpu->arch.vzguestid[cpu]);
2540	} else {
2541		/*
2542		 * The Guest TLB only stores a single guest's TLB state, so
2543		 * flush it if another VCPU has executed on this CPU.
2544		 *
2545		 * We also flush if we've executed on another CPU, as the guest
2546		 * mappings may have changed without hypervisor knowledge.
2547		 */
2548		if (migrated || last_exec_vcpu[cpu] != vcpu)
2549			kvm_vz_local_flush_guesttlb_all();
2550		last_exec_vcpu[cpu] = vcpu;
2551
2552		/*
2553		 * Root ASID dealiases guest GPA mappings in the root TLB.
2554		 * Allocate new root ASID if needed.
2555		 */
2556		if (cpumask_test_and_clear_cpu(cpu, &kvm->arch.asid_flush_mask))
2557			get_new_mmu_context(gpa_mm);
2558		else
2559			check_mmu_context(gpa_mm);
2560	}
2561}
2562
2563static int kvm_vz_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
2564{
2565	struct mips_coproc *cop0 = &vcpu->arch.cop0;
2566	bool migrated, all;
2567
2568	/*
2569	 * Have we migrated to a different CPU?
2570	 * If so, any old guest TLB state may be stale.
2571	 */
2572	migrated = (vcpu->arch.last_sched_cpu != cpu);
2573
2574	/*
2575	 * Was this the last VCPU to run on this CPU?
2576	 * If not, any old guest state from this VCPU will have been clobbered.
2577	 */
2578	all = migrated || (last_vcpu[cpu] != vcpu);
2579	last_vcpu[cpu] = vcpu;
2580
2581	/*
2582	 * Restore CP0_Wired unconditionally as we clear it after use, and
2583	 * restore wired guest TLB entries (while in guest context).
2584	 */
2585	kvm_restore_gc0_wired(cop0);
2586	if (current->flags & PF_VCPU) {
2587		tlbw_use_hazard();
2588		kvm_vz_vcpu_load_tlb(vcpu, cpu);
2589		kvm_vz_vcpu_load_wired(vcpu);
2590	}
2591
2592	/*
2593	 * Restore timer state regardless, as e.g. Cause.TI can change over time
2594	 * if left unmaintained.
2595	 */
2596	kvm_vz_restore_timer(vcpu);
2597
2598	/* Set MC bit if we want to trace guest mode changes */
2599	if (kvm_trace_guest_mode_change)
2600		set_c0_guestctl0(MIPS_GCTL0_MC);
2601	else
2602		clear_c0_guestctl0(MIPS_GCTL0_MC);
2603
2604	/* Don't bother restoring registers multiple times unless necessary */
2605	if (!all)
2606		return 0;
2607
2608	/*
2609	 * Restore config registers first, as some implementations restrict
2610	 * writes to other registers when the corresponding feature bits aren't
2611	 * set. For example Status.CU1 cannot be set unless Config1.FP is set.
2612	 */
2613	kvm_restore_gc0_config(cop0);
2614	if (cpu_guest_has_conf1)
2615		kvm_restore_gc0_config1(cop0);
2616	if (cpu_guest_has_conf2)
2617		kvm_restore_gc0_config2(cop0);
2618	if (cpu_guest_has_conf3)
2619		kvm_restore_gc0_config3(cop0);
2620	if (cpu_guest_has_conf4)
2621		kvm_restore_gc0_config4(cop0);
2622	if (cpu_guest_has_conf5)
2623		kvm_restore_gc0_config5(cop0);
2624	if (cpu_guest_has_conf6)
2625		kvm_restore_gc0_config6(cop0);
2626	if (cpu_guest_has_conf7)
2627		kvm_restore_gc0_config7(cop0);
2628
2629	kvm_restore_gc0_index(cop0);
2630	kvm_restore_gc0_entrylo0(cop0);
2631	kvm_restore_gc0_entrylo1(cop0);
2632	kvm_restore_gc0_context(cop0);
2633	if (cpu_guest_has_contextconfig)
2634		kvm_restore_gc0_contextconfig(cop0);
2635#ifdef CONFIG_64BIT
2636	kvm_restore_gc0_xcontext(cop0);
2637	if (cpu_guest_has_contextconfig)
2638		kvm_restore_gc0_xcontextconfig(cop0);
2639#endif
2640	kvm_restore_gc0_pagemask(cop0);
2641	kvm_restore_gc0_pagegrain(cop0);
2642	kvm_restore_gc0_hwrena(cop0);
2643	kvm_restore_gc0_badvaddr(cop0);
2644	kvm_restore_gc0_entryhi(cop0);
2645	kvm_restore_gc0_status(cop0);
2646	kvm_restore_gc0_intctl(cop0);
2647	kvm_restore_gc0_epc(cop0);
2648	kvm_vz_write_gc0_ebase(kvm_read_sw_gc0_ebase(cop0));
2649	if (cpu_guest_has_userlocal)
2650		kvm_restore_gc0_userlocal(cop0);
2651
2652	kvm_restore_gc0_errorepc(cop0);
2653
2654	/* restore KScratch registers if enabled in guest */
2655	if (cpu_guest_has_conf4) {
2656		if (cpu_guest_has_kscr(2))
2657			kvm_restore_gc0_kscratch1(cop0);
2658		if (cpu_guest_has_kscr(3))
2659			kvm_restore_gc0_kscratch2(cop0);
2660		if (cpu_guest_has_kscr(4))
2661			kvm_restore_gc0_kscratch3(cop0);
2662		if (cpu_guest_has_kscr(5))
2663			kvm_restore_gc0_kscratch4(cop0);
2664		if (cpu_guest_has_kscr(6))
2665			kvm_restore_gc0_kscratch5(cop0);
2666		if (cpu_guest_has_kscr(7))
2667			kvm_restore_gc0_kscratch6(cop0);
2668	}
2669
2670	if (cpu_guest_has_badinstr)
2671		kvm_restore_gc0_badinstr(cop0);
2672	if (cpu_guest_has_badinstrp)
2673		kvm_restore_gc0_badinstrp(cop0);
2674
2675	if (cpu_guest_has_segments) {
2676		kvm_restore_gc0_segctl0(cop0);
2677		kvm_restore_gc0_segctl1(cop0);
2678		kvm_restore_gc0_segctl2(cop0);
2679	}
2680
2681	/* restore HTW registers */
2682	if (cpu_guest_has_htw || cpu_guest_has_ldpte) {
2683		kvm_restore_gc0_pwbase(cop0);
2684		kvm_restore_gc0_pwfield(cop0);
2685		kvm_restore_gc0_pwsize(cop0);
2686		kvm_restore_gc0_pwctl(cop0);
2687	}
2688
2689	/* restore Root.GuestCtl2 from unused Guest guestctl2 register */
2690	if (cpu_has_guestctl2)
2691		write_c0_guestctl2(
2692			cop0->reg[MIPS_CP0_GUESTCTL2][MIPS_CP0_GUESTCTL2_SEL]);
2693
2694	/*
2695	 * We should clear linked load bit to break interrupted atomics. This
2696	 * prevents a SC on the next VCPU from succeeding by matching a LL on
2697	 * the previous VCPU.
2698	 */
2699	if (vcpu->kvm->created_vcpus > 1)
2700		write_gc0_lladdr(0);
2701
2702	return 0;
2703}
2704
2705static int kvm_vz_vcpu_put(struct kvm_vcpu *vcpu, int cpu)
2706{
2707	struct mips_coproc *cop0 = &vcpu->arch.cop0;
2708
2709	if (current->flags & PF_VCPU)
2710		kvm_vz_vcpu_save_wired(vcpu);
2711
2712	kvm_lose_fpu(vcpu);
2713
2714	kvm_save_gc0_index(cop0);
2715	kvm_save_gc0_entrylo0(cop0);
2716	kvm_save_gc0_entrylo1(cop0);
2717	kvm_save_gc0_context(cop0);
2718	if (cpu_guest_has_contextconfig)
2719		kvm_save_gc0_contextconfig(cop0);
2720#ifdef CONFIG_64BIT
2721	kvm_save_gc0_xcontext(cop0);
2722	if (cpu_guest_has_contextconfig)
2723		kvm_save_gc0_xcontextconfig(cop0);
2724#endif
2725	kvm_save_gc0_pagemask(cop0);
2726	kvm_save_gc0_pagegrain(cop0);
2727	kvm_save_gc0_wired(cop0);
2728	/* allow wired TLB entries to be overwritten */
2729	clear_gc0_wired(MIPSR6_WIRED_WIRED);
2730	kvm_save_gc0_hwrena(cop0);
2731	kvm_save_gc0_badvaddr(cop0);
2732	kvm_save_gc0_entryhi(cop0);
2733	kvm_save_gc0_status(cop0);
2734	kvm_save_gc0_intctl(cop0);
2735	kvm_save_gc0_epc(cop0);
2736	kvm_write_sw_gc0_ebase(cop0, kvm_vz_read_gc0_ebase());
2737	if (cpu_guest_has_userlocal)
2738		kvm_save_gc0_userlocal(cop0);
2739
2740	/* only save implemented config registers */
2741	kvm_save_gc0_config(cop0);
2742	if (cpu_guest_has_conf1)
2743		kvm_save_gc0_config1(cop0);
2744	if (cpu_guest_has_conf2)
2745		kvm_save_gc0_config2(cop0);
2746	if (cpu_guest_has_conf3)
2747		kvm_save_gc0_config3(cop0);
2748	if (cpu_guest_has_conf4)
2749		kvm_save_gc0_config4(cop0);
2750	if (cpu_guest_has_conf5)
2751		kvm_save_gc0_config5(cop0);
2752	if (cpu_guest_has_conf6)
2753		kvm_save_gc0_config6(cop0);
2754	if (cpu_guest_has_conf7)
2755		kvm_save_gc0_config7(cop0);
2756
2757	kvm_save_gc0_errorepc(cop0);
2758
2759	/* save KScratch registers if enabled in guest */
2760	if (cpu_guest_has_conf4) {
2761		if (cpu_guest_has_kscr(2))
2762			kvm_save_gc0_kscratch1(cop0);
2763		if (cpu_guest_has_kscr(3))
2764			kvm_save_gc0_kscratch2(cop0);
2765		if (cpu_guest_has_kscr(4))
2766			kvm_save_gc0_kscratch3(cop0);
2767		if (cpu_guest_has_kscr(5))
2768			kvm_save_gc0_kscratch4(cop0);
2769		if (cpu_guest_has_kscr(6))
2770			kvm_save_gc0_kscratch5(cop0);
2771		if (cpu_guest_has_kscr(7))
2772			kvm_save_gc0_kscratch6(cop0);
2773	}
2774
2775	if (cpu_guest_has_badinstr)
2776		kvm_save_gc0_badinstr(cop0);
2777	if (cpu_guest_has_badinstrp)
2778		kvm_save_gc0_badinstrp(cop0);
2779
2780	if (cpu_guest_has_segments) {
2781		kvm_save_gc0_segctl0(cop0);
2782		kvm_save_gc0_segctl1(cop0);
2783		kvm_save_gc0_segctl2(cop0);
2784	}
2785
2786	/* save HTW registers if enabled in guest */
2787	if (cpu_guest_has_ldpte || (cpu_guest_has_htw &&
2788	    kvm_read_sw_gc0_config3(cop0) & MIPS_CONF3_PW)) {
2789		kvm_save_gc0_pwbase(cop0);
2790		kvm_save_gc0_pwfield(cop0);
2791		kvm_save_gc0_pwsize(cop0);
2792		kvm_save_gc0_pwctl(cop0);
2793	}
2794
2795	kvm_vz_save_timer(vcpu);
2796
2797	/* save Root.GuestCtl2 in unused Guest guestctl2 register */
2798	if (cpu_has_guestctl2)
2799		cop0->reg[MIPS_CP0_GUESTCTL2][MIPS_CP0_GUESTCTL2_SEL] =
2800			read_c0_guestctl2();
2801
2802	return 0;
2803}
2804
2805/**
2806 * kvm_vz_resize_guest_vtlb() - Attempt to resize guest VTLB.
2807 * @size:	Number of guest VTLB entries (0 < @size <= root VTLB entries).
2808 *
2809 * Attempt to resize the guest VTLB by writing guest Config registers. This is
2810 * necessary for cores with a shared root/guest TLB to avoid overlap with wired
2811 * entries in the root VTLB.
2812 *
2813 * Returns:	The resulting guest VTLB size.
2814 */
2815static unsigned int kvm_vz_resize_guest_vtlb(unsigned int size)
2816{
2817	unsigned int config4 = 0, ret = 0, limit;
2818
2819	/* Write MMUSize - 1 into guest Config registers */
2820	if (cpu_guest_has_conf1)
2821		change_gc0_config1(MIPS_CONF1_TLBS,
2822				   (size - 1) << MIPS_CONF1_TLBS_SHIFT);
2823	if (cpu_guest_has_conf4) {
2824		config4 = read_gc0_config4();
2825		if (cpu_has_mips_r6 || (config4 & MIPS_CONF4_MMUEXTDEF) ==
2826		    MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT) {
2827			config4 &= ~MIPS_CONF4_VTLBSIZEEXT;
2828			config4 |= ((size - 1) >> MIPS_CONF1_TLBS_SIZE) <<
2829				MIPS_CONF4_VTLBSIZEEXT_SHIFT;
2830		} else if ((config4 & MIPS_CONF4_MMUEXTDEF) ==
2831			   MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT) {
2832			config4 &= ~MIPS_CONF4_MMUSIZEEXT;
2833			config4 |= ((size - 1) >> MIPS_CONF1_TLBS_SIZE) <<
2834				MIPS_CONF4_MMUSIZEEXT_SHIFT;
2835		}
2836		write_gc0_config4(config4);
2837	}
2838
2839	/*
2840	 * Set Guest.Wired.Limit = 0 (no limit up to Guest.MMUSize-1), unless it
2841	 * would exceed Root.Wired.Limit (clearing Guest.Wired.Wired so write
2842	 * not dropped)
2843	 */
2844	if (cpu_has_mips_r6) {
2845		limit = (read_c0_wired() & MIPSR6_WIRED_LIMIT) >>
2846						MIPSR6_WIRED_LIMIT_SHIFT;
2847		if (size - 1 <= limit)
2848			limit = 0;
2849		write_gc0_wired(limit << MIPSR6_WIRED_LIMIT_SHIFT);
2850	}
2851
2852	/* Read back MMUSize - 1 */
2853	back_to_back_c0_hazard();
2854	if (cpu_guest_has_conf1)
2855		ret = (read_gc0_config1() & MIPS_CONF1_TLBS) >>
2856						MIPS_CONF1_TLBS_SHIFT;
2857	if (config4) {
2858		if (cpu_has_mips_r6 || (config4 & MIPS_CONF4_MMUEXTDEF) ==
2859		    MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT)
2860			ret |= ((config4 & MIPS_CONF4_VTLBSIZEEXT) >>
2861				MIPS_CONF4_VTLBSIZEEXT_SHIFT) <<
2862				MIPS_CONF1_TLBS_SIZE;
2863		else if ((config4 & MIPS_CONF4_MMUEXTDEF) ==
2864			 MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT)
2865			ret |= ((config4 & MIPS_CONF4_MMUSIZEEXT) >>
2866				MIPS_CONF4_MMUSIZEEXT_SHIFT) <<
2867				MIPS_CONF1_TLBS_SIZE;
2868	}
2869	return ret + 1;
2870}
2871
2872static int kvm_vz_hardware_enable(void)
2873{
2874	unsigned int mmu_size, guest_mmu_size, ftlb_size;
2875	u64 guest_cvmctl, cvmvmconfig;
2876
2877	switch (current_cpu_type()) {
2878	case CPU_CAVIUM_OCTEON3:
2879		/* Set up guest timer/perfcount IRQ lines */
2880		guest_cvmctl = read_gc0_cvmctl();
2881		guest_cvmctl &= ~CVMCTL_IPTI;
2882		guest_cvmctl |= 7ull << CVMCTL_IPTI_SHIFT;
2883		guest_cvmctl &= ~CVMCTL_IPPCI;
2884		guest_cvmctl |= 6ull << CVMCTL_IPPCI_SHIFT;
2885		write_gc0_cvmctl(guest_cvmctl);
2886
2887		cvmvmconfig = read_c0_cvmvmconfig();
2888		/* No I/O hole translation. */
2889		cvmvmconfig |= CVMVMCONF_DGHT;
2890		/* Halve the root MMU size */
2891		mmu_size = ((cvmvmconfig & CVMVMCONF_MMUSIZEM1)
2892			    >> CVMVMCONF_MMUSIZEM1_S) + 1;
2893		guest_mmu_size = mmu_size / 2;
2894		mmu_size -= guest_mmu_size;
2895		cvmvmconfig &= ~CVMVMCONF_RMMUSIZEM1;
2896		cvmvmconfig |= mmu_size - 1;
2897		write_c0_cvmvmconfig(cvmvmconfig);
2898
2899		/* Update our records */
2900		current_cpu_data.tlbsize = mmu_size;
2901		current_cpu_data.tlbsizevtlb = mmu_size;
2902		current_cpu_data.guest.tlbsize = guest_mmu_size;
2903
2904		/* Flush moved entries in new (guest) context */
2905		kvm_vz_local_flush_guesttlb_all();
2906		break;
2907	default:
2908		/*
2909		 * ImgTec cores tend to use a shared root/guest TLB. To avoid
2910		 * overlap of root wired and guest entries, the guest TLB may
2911		 * need resizing.
2912		 */
2913		mmu_size = current_cpu_data.tlbsizevtlb;
2914		ftlb_size = current_cpu_data.tlbsize - mmu_size;
2915
2916		/* Try switching to maximum guest VTLB size for flush */
2917		guest_mmu_size = kvm_vz_resize_guest_vtlb(mmu_size);
2918		current_cpu_data.guest.tlbsize = guest_mmu_size + ftlb_size;
2919		kvm_vz_local_flush_guesttlb_all();
2920
2921		/*
2922		 * Reduce to make space for root wired entries and at least 2
2923		 * root non-wired entries. This does assume that long-term wired
2924		 * entries won't be added later.
2925		 */
2926		guest_mmu_size = mmu_size - num_wired_entries() - 2;
2927		guest_mmu_size = kvm_vz_resize_guest_vtlb(guest_mmu_size);
2928		current_cpu_data.guest.tlbsize = guest_mmu_size + ftlb_size;
2929
2930		/*
2931		 * Write the VTLB size, but if another CPU has already written,
2932		 * check it matches or we won't provide a consistent view to the
2933		 * guest. If this ever happens it suggests an asymmetric number
2934		 * of wired entries.
2935		 */
2936		if (cmpxchg(&kvm_vz_guest_vtlb_size, 0, guest_mmu_size) &&
2937		    WARN(guest_mmu_size != kvm_vz_guest_vtlb_size,
2938			 "Available guest VTLB size mismatch"))
2939			return -EINVAL;
2940		break;
2941	}
2942
2943	/*
2944	 * Enable virtualization features granting guest direct control of
2945	 * certain features:
2946	 * CP0=1:	Guest coprocessor 0 context.
2947	 * AT=Guest:	Guest MMU.
2948	 * CG=1:	Hit (virtual address) CACHE operations (optional).
2949	 * CF=1:	Guest Config registers.
2950	 * CGI=1:	Indexed flush CACHE operations (optional).
2951	 */
2952	write_c0_guestctl0(MIPS_GCTL0_CP0 |
2953			   (MIPS_GCTL0_AT_GUEST << MIPS_GCTL0_AT_SHIFT) |
2954			   MIPS_GCTL0_CG | MIPS_GCTL0_CF);
2955	if (cpu_has_guestctl0ext) {
2956		if (current_cpu_type() != CPU_LOONGSON64)
2957			set_c0_guestctl0ext(MIPS_GCTL0EXT_CGI);
2958		else
2959			clear_c0_guestctl0ext(MIPS_GCTL0EXT_CGI);
2960	}
2961
2962	if (cpu_has_guestid) {
2963		write_c0_guestctl1(0);
2964		kvm_vz_local_flush_roottlb_all_guests();
2965
2966		GUESTID_MASK = current_cpu_data.guestid_mask;
2967		GUESTID_FIRST_VERSION = GUESTID_MASK + 1;
2968		GUESTID_VERSION_MASK = ~GUESTID_MASK;
2969
2970		current_cpu_data.guestid_cache = GUESTID_FIRST_VERSION;
2971	}
2972
2973	/* clear any pending injected virtual guest interrupts */
2974	if (cpu_has_guestctl2)
2975		clear_c0_guestctl2(0x3f << 10);
2976
2977#ifdef CONFIG_CPU_LOONGSON64
2978	/* Control guest CCA attribute */
2979	if (cpu_has_csr())
2980		csr_writel(csr_readl(0xffffffec) | 0x1, 0xffffffec);
2981#endif
2982
2983	return 0;
2984}
2985
2986static void kvm_vz_hardware_disable(void)
2987{
2988	u64 cvmvmconfig;
2989	unsigned int mmu_size;
2990
2991	/* Flush any remaining guest TLB entries */
2992	kvm_vz_local_flush_guesttlb_all();
2993
2994	switch (current_cpu_type()) {
2995	case CPU_CAVIUM_OCTEON3:
2996		/*
2997		 * Allocate whole TLB for root. Existing guest TLB entries will
2998		 * change ownership to the root TLB. We should be safe though as
2999		 * they've already been flushed above while in guest TLB.
3000		 */
3001		cvmvmconfig = read_c0_cvmvmconfig();
3002		mmu_size = ((cvmvmconfig & CVMVMCONF_MMUSIZEM1)
3003			    >> CVMVMCONF_MMUSIZEM1_S) + 1;
3004		cvmvmconfig &= ~CVMVMCONF_RMMUSIZEM1;
3005		cvmvmconfig |= mmu_size - 1;
3006		write_c0_cvmvmconfig(cvmvmconfig);
3007
3008		/* Update our records */
3009		current_cpu_data.tlbsize = mmu_size;
3010		current_cpu_data.tlbsizevtlb = mmu_size;
3011		current_cpu_data.guest.tlbsize = 0;
3012
3013		/* Flush moved entries in new (root) context */
3014		local_flush_tlb_all();
3015		break;
3016	}
3017
3018	if (cpu_has_guestid) {
3019		write_c0_guestctl1(0);
3020		kvm_vz_local_flush_roottlb_all_guests();
3021	}
3022}
3023
3024static int kvm_vz_check_extension(struct kvm *kvm, long ext)
3025{
3026	int r;
3027
3028	switch (ext) {
3029	case KVM_CAP_MIPS_VZ:
3030		/* we wouldn't be here unless cpu_has_vz */
3031		r = 1;
3032		break;
3033#ifdef CONFIG_64BIT
3034	case KVM_CAP_MIPS_64BIT:
3035		/* We support 64-bit registers/operations and addresses */
3036		r = 2;
3037		break;
3038#endif
3039	case KVM_CAP_IOEVENTFD:
3040		r = 1;
3041		break;
3042	default:
3043		r = 0;
3044		break;
3045	}
3046
3047	return r;
3048}
3049
3050static int kvm_vz_vcpu_init(struct kvm_vcpu *vcpu)
3051{
3052	int i;
3053
3054	for_each_possible_cpu(i)
3055		vcpu->arch.vzguestid[i] = 0;
3056
3057	return 0;
3058}
3059
3060static void kvm_vz_vcpu_uninit(struct kvm_vcpu *vcpu)
3061{
3062	int cpu;
3063
3064	/*
3065	 * If the VCPU is freed and reused as another VCPU, we don't want the
3066	 * matching pointer wrongly hanging around in last_vcpu[] or
3067	 * last_exec_vcpu[].
3068	 */
3069	for_each_possible_cpu(cpu) {
3070		if (last_vcpu[cpu] == vcpu)
3071			last_vcpu[cpu] = NULL;
3072		if (last_exec_vcpu[cpu] == vcpu)
3073			last_exec_vcpu[cpu] = NULL;
3074	}
3075}
3076
3077static int kvm_vz_vcpu_setup(struct kvm_vcpu *vcpu)
3078{
3079	struct mips_coproc *cop0 = &vcpu->arch.cop0;
3080	unsigned long count_hz = 100*1000*1000; /* default to 100 MHz */
3081
3082	/*
3083	 * Start off the timer at the same frequency as the host timer, but the
3084	 * soft timer doesn't handle frequencies greater than 1GHz yet.
3085	 */
3086	if (mips_hpt_frequency && mips_hpt_frequency <= NSEC_PER_SEC)
3087		count_hz = mips_hpt_frequency;
3088	kvm_mips_init_count(vcpu, count_hz);
3089
3090	/*
3091	 * Initialize guest register state to valid architectural reset state.
3092	 */
3093
3094	/* PageGrain */
3095	if (cpu_has_mips_r5 || cpu_has_mips_r6)
3096		kvm_write_sw_gc0_pagegrain(cop0, PG_RIE | PG_XIE | PG_IEC);
3097	/* Wired */
3098	if (cpu_has_mips_r6)
3099		kvm_write_sw_gc0_wired(cop0,
3100				       read_gc0_wired() & MIPSR6_WIRED_LIMIT);
3101	/* Status */
3102	kvm_write_sw_gc0_status(cop0, ST0_BEV | ST0_ERL);
3103	if (cpu_has_mips_r5 || cpu_has_mips_r6)
3104		kvm_change_sw_gc0_status(cop0, ST0_FR, read_gc0_status());
3105	/* IntCtl */
3106	kvm_write_sw_gc0_intctl(cop0, read_gc0_intctl() &
3107				(INTCTLF_IPFDC | INTCTLF_IPPCI | INTCTLF_IPTI));
3108	/* PRId */
3109	kvm_write_sw_gc0_prid(cop0, boot_cpu_data.processor_id);
3110	/* EBase */
3111	kvm_write_sw_gc0_ebase(cop0, (s32)0x80000000 | vcpu->vcpu_id);
3112	/* Config */
3113	kvm_save_gc0_config(cop0);
3114	/* architecturally writable (e.g. from guest) */
3115	kvm_change_sw_gc0_config(cop0, CONF_CM_CMASK,
3116				 _page_cachable_default >> _CACHE_SHIFT);
3117	/* architecturally read only, but maybe writable from root */
3118	kvm_change_sw_gc0_config(cop0, MIPS_CONF_MT, read_c0_config());
3119	if (cpu_guest_has_conf1) {
3120		kvm_set_sw_gc0_config(cop0, MIPS_CONF_M);
3121		/* Config1 */
3122		kvm_save_gc0_config1(cop0);
3123		/* architecturally read only, but maybe writable from root */
3124		kvm_clear_sw_gc0_config1(cop0, MIPS_CONF1_C2	|
3125					       MIPS_CONF1_MD	|
3126					       MIPS_CONF1_PC	|
3127					       MIPS_CONF1_WR	|
3128					       MIPS_CONF1_CA	|
3129					       MIPS_CONF1_FP);
3130	}
3131	if (cpu_guest_has_conf2) {
3132		kvm_set_sw_gc0_config1(cop0, MIPS_CONF_M);
3133		/* Config2 */
3134		kvm_save_gc0_config2(cop0);
3135	}
3136	if (cpu_guest_has_conf3) {
3137		kvm_set_sw_gc0_config2(cop0, MIPS_CONF_M);
3138		/* Config3 */
3139		kvm_save_gc0_config3(cop0);
3140		/* architecturally writable (e.g. from guest) */
3141		kvm_clear_sw_gc0_config3(cop0, MIPS_CONF3_ISA_OE);
3142		/* architecturally read only, but maybe writable from root */
3143		kvm_clear_sw_gc0_config3(cop0, MIPS_CONF3_MSA	|
3144					       MIPS_CONF3_BPG	|
3145					       MIPS_CONF3_ULRI	|
3146					       MIPS_CONF3_DSP	|
3147					       MIPS_CONF3_CTXTC	|
3148					       MIPS_CONF3_ITL	|
3149					       MIPS_CONF3_LPA	|
3150					       MIPS_CONF3_VEIC	|
3151					       MIPS_CONF3_VINT	|
3152					       MIPS_CONF3_SP	|
3153					       MIPS_CONF3_CDMM	|
3154					       MIPS_CONF3_MT	|
3155					       MIPS_CONF3_SM	|
3156					       MIPS_CONF3_TL);
3157	}
3158	if (cpu_guest_has_conf4) {
3159		kvm_set_sw_gc0_config3(cop0, MIPS_CONF_M);
3160		/* Config4 */
3161		kvm_save_gc0_config4(cop0);
3162	}
3163	if (cpu_guest_has_conf5) {
3164		kvm_set_sw_gc0_config4(cop0, MIPS_CONF_M);
3165		/* Config5 */
3166		kvm_save_gc0_config5(cop0);
3167		/* architecturally writable (e.g. from guest) */
3168		kvm_clear_sw_gc0_config5(cop0, MIPS_CONF5_K	|
3169					       MIPS_CONF5_CV	|
3170					       MIPS_CONF5_MSAEN	|
3171					       MIPS_CONF5_UFE	|
3172					       MIPS_CONF5_FRE	|
3173					       MIPS_CONF5_SBRI	|
3174					       MIPS_CONF5_UFR);
3175		/* architecturally read only, but maybe writable from root */
3176		kvm_clear_sw_gc0_config5(cop0, MIPS_CONF5_MRP);
3177	}
3178
3179	if (cpu_guest_has_contextconfig) {
3180		/* ContextConfig */
3181		kvm_write_sw_gc0_contextconfig(cop0, 0x007ffff0);
3182#ifdef CONFIG_64BIT
3183		/* XContextConfig */
3184		/* bits SEGBITS-13+3:4 set */
3185		kvm_write_sw_gc0_xcontextconfig(cop0,
3186					((1ull << (cpu_vmbits - 13)) - 1) << 4);
3187#endif
3188	}
3189
3190	/* Implementation dependent, use the legacy layout */
3191	if (cpu_guest_has_segments) {
3192		/* SegCtl0, SegCtl1, SegCtl2 */
3193		kvm_write_sw_gc0_segctl0(cop0, 0x00200010);
3194		kvm_write_sw_gc0_segctl1(cop0, 0x00000002 |
3195				(_page_cachable_default >> _CACHE_SHIFT) <<
3196						(16 + MIPS_SEGCFG_C_SHIFT));
3197		kvm_write_sw_gc0_segctl2(cop0, 0x00380438);
3198	}
3199
3200	/* reset HTW registers */
3201	if (cpu_guest_has_htw && (cpu_has_mips_r5 || cpu_has_mips_r6)) {
3202		/* PWField */
3203		kvm_write_sw_gc0_pwfield(cop0, 0x0c30c302);
3204		/* PWSize */
3205		kvm_write_sw_gc0_pwsize(cop0, 1 << MIPS_PWSIZE_PTW_SHIFT);
3206	}
3207
3208	/* start with no pending virtual guest interrupts */
3209	if (cpu_has_guestctl2)
3210		cop0->reg[MIPS_CP0_GUESTCTL2][MIPS_CP0_GUESTCTL2_SEL] = 0;
3211
3212	/* Put PC at reset vector */
3213	vcpu->arch.pc = CKSEG1ADDR(0x1fc00000);
3214
3215	return 0;
3216}
3217
3218static void kvm_vz_prepare_flush_shadow(struct kvm *kvm)
3219{
3220	if (!cpu_has_guestid) {
3221		/*
3222		 * For each CPU there is a single GPA ASID used by all VCPUs in
3223		 * the VM, so it doesn't make sense for the VCPUs to handle
3224		 * invalidation of these ASIDs individually.
3225		 *
3226		 * Instead mark all CPUs as needing ASID invalidation in
3227		 * asid_flush_mask, and kvm_flush_remote_tlbs(kvm) will
3228		 * kick any running VCPUs so they check asid_flush_mask.
3229		 */
3230		cpumask_setall(&kvm->arch.asid_flush_mask);
3231	}
3232}
3233
3234static void kvm_vz_vcpu_reenter(struct kvm_vcpu *vcpu)
3235{
3236	int cpu = smp_processor_id();
3237	int preserve_guest_tlb;
3238
3239	preserve_guest_tlb = kvm_vz_check_requests(vcpu, cpu);
3240
3241	if (preserve_guest_tlb)
3242		kvm_vz_vcpu_save_wired(vcpu);
3243
3244	kvm_vz_vcpu_load_tlb(vcpu, cpu);
3245
3246	if (preserve_guest_tlb)
3247		kvm_vz_vcpu_load_wired(vcpu);
3248}
3249
3250static int kvm_vz_vcpu_run(struct kvm_vcpu *vcpu)
3251{
3252	int cpu = smp_processor_id();
3253	int r;
3254
3255	kvm_vz_acquire_htimer(vcpu);
3256	/* Check if we have any exceptions/interrupts pending */
3257	kvm_mips_deliver_interrupts(vcpu, read_gc0_cause());
3258
3259	kvm_vz_check_requests(vcpu, cpu);
3260	kvm_vz_vcpu_load_tlb(vcpu, cpu);
3261	kvm_vz_vcpu_load_wired(vcpu);
3262
3263	r = vcpu->arch.vcpu_run(vcpu);
3264
3265	kvm_vz_vcpu_save_wired(vcpu);
3266
3267	return r;
3268}
3269
3270static struct kvm_mips_callbacks kvm_vz_callbacks = {
3271	.handle_cop_unusable = kvm_trap_vz_handle_cop_unusable,
3272	.handle_tlb_mod = kvm_trap_vz_handle_tlb_st_miss,
3273	.handle_tlb_ld_miss = kvm_trap_vz_handle_tlb_ld_miss,
3274	.handle_tlb_st_miss = kvm_trap_vz_handle_tlb_st_miss,
3275	.handle_addr_err_st = kvm_trap_vz_no_handler,
3276	.handle_addr_err_ld = kvm_trap_vz_no_handler,
3277	.handle_syscall = kvm_trap_vz_no_handler,
3278	.handle_res_inst = kvm_trap_vz_no_handler,
3279	.handle_break = kvm_trap_vz_no_handler,
3280	.handle_msa_disabled = kvm_trap_vz_handle_msa_disabled,
3281	.handle_guest_exit = kvm_trap_vz_handle_guest_exit,
3282
3283	.hardware_enable = kvm_vz_hardware_enable,
3284	.hardware_disable = kvm_vz_hardware_disable,
3285	.check_extension = kvm_vz_check_extension,
3286	.vcpu_init = kvm_vz_vcpu_init,
3287	.vcpu_uninit = kvm_vz_vcpu_uninit,
3288	.vcpu_setup = kvm_vz_vcpu_setup,
3289	.prepare_flush_shadow = kvm_vz_prepare_flush_shadow,
3290	.gva_to_gpa = kvm_vz_gva_to_gpa_cb,
3291	.queue_timer_int = kvm_vz_queue_timer_int_cb,
3292	.dequeue_timer_int = kvm_vz_dequeue_timer_int_cb,
3293	.queue_io_int = kvm_vz_queue_io_int_cb,
3294	.dequeue_io_int = kvm_vz_dequeue_io_int_cb,
3295	.irq_deliver = kvm_vz_irq_deliver_cb,
3296	.irq_clear = kvm_vz_irq_clear_cb,
3297	.num_regs = kvm_vz_num_regs,
3298	.copy_reg_indices = kvm_vz_copy_reg_indices,
3299	.get_one_reg = kvm_vz_get_one_reg,
3300	.set_one_reg = kvm_vz_set_one_reg,
3301	.vcpu_load = kvm_vz_vcpu_load,
3302	.vcpu_put = kvm_vz_vcpu_put,
3303	.vcpu_run = kvm_vz_vcpu_run,
3304	.vcpu_reenter = kvm_vz_vcpu_reenter,
3305};
3306
3307/* FIXME: Get rid of the callbacks now that trap-and-emulate is gone. */
3308const struct kvm_mips_callbacks * const kvm_mips_callbacks = &kvm_vz_callbacks;
3309
3310int kvm_mips_emulation_init(void)
3311{
3312	if (!cpu_has_vz)
3313		return -ENODEV;
3314
3315	/*
3316	 * VZ requires at least 2 KScratch registers, so it should have been
3317	 * possible to allocate pgd_reg.
3318	 */
3319	if (WARN(pgd_reg == -1,
3320		 "pgd_reg not allocated even though cpu_has_vz\n"))
3321		return -ENODEV;
3322
3323	pr_info("Starting KVM with MIPS VZ extensions\n");
3324	return 0;
3325}
3326