xref: /openbmc/linux/arch/mips/kvm/vz.c (revision c992a4f6)
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 
33 #include "trace.h"
34 
35 /* Pointers to last VCPU loaded on each physical CPU */
36 static struct kvm_vcpu *last_vcpu[NR_CPUS];
37 /* Pointers to last VCPU executed on each physical CPU */
38 static struct kvm_vcpu *last_exec_vcpu[NR_CPUS];
39 
40 /*
41  * Number of guest VTLB entries to use, so we can catch inconsistency between
42  * CPUs.
43  */
44 static unsigned int kvm_vz_guest_vtlb_size;
45 
46 static inline long kvm_vz_read_gc0_ebase(void)
47 {
48 	if (sizeof(long) == 8 && cpu_has_ebase_wg)
49 		return read_gc0_ebase_64();
50 	else
51 		return read_gc0_ebase();
52 }
53 
54 static inline void kvm_vz_write_gc0_ebase(long v)
55 {
56 	/*
57 	 * First write with WG=1 to write upper bits, then write again in case
58 	 * WG should be left at 0.
59 	 * write_gc0_ebase_64() is no longer UNDEFINED since R6.
60 	 */
61 	if (sizeof(long) == 8 &&
62 	    (cpu_has_mips64r6 || cpu_has_ebase_wg)) {
63 		write_gc0_ebase_64(v | MIPS_EBASE_WG);
64 		write_gc0_ebase_64(v);
65 	} else {
66 		write_gc0_ebase(v | MIPS_EBASE_WG);
67 		write_gc0_ebase(v);
68 	}
69 }
70 
71 /*
72  * These Config bits may be writable by the guest:
73  * Config:	[K23, KU] (!TLB), K0
74  * Config1:	(none)
75  * Config2:	[TU, SU] (impl)
76  * Config3:	ISAOnExc
77  * Config4:	FTLBPageSize
78  * Config5:	K, CV, MSAEn, UFE, FRE, SBRI, UFR
79  */
80 
81 static inline unsigned int kvm_vz_config_guest_wrmask(struct kvm_vcpu *vcpu)
82 {
83 	return CONF_CM_CMASK;
84 }
85 
86 static inline unsigned int kvm_vz_config1_guest_wrmask(struct kvm_vcpu *vcpu)
87 {
88 	return 0;
89 }
90 
91 static inline unsigned int kvm_vz_config2_guest_wrmask(struct kvm_vcpu *vcpu)
92 {
93 	return 0;
94 }
95 
96 static inline unsigned int kvm_vz_config3_guest_wrmask(struct kvm_vcpu *vcpu)
97 {
98 	return MIPS_CONF3_ISA_OE;
99 }
100 
101 static inline unsigned int kvm_vz_config4_guest_wrmask(struct kvm_vcpu *vcpu)
102 {
103 	/* no need to be exact */
104 	return MIPS_CONF4_VFTLBPAGESIZE;
105 }
106 
107 static inline unsigned int kvm_vz_config5_guest_wrmask(struct kvm_vcpu *vcpu)
108 {
109 	unsigned int mask = MIPS_CONF5_K | MIPS_CONF5_CV | MIPS_CONF5_SBRI;
110 
111 	/* Permit MSAEn changes if MSA supported and enabled */
112 	if (kvm_mips_guest_has_msa(&vcpu->arch))
113 		mask |= MIPS_CONF5_MSAEN;
114 
115 	/*
116 	 * Permit guest FPU mode changes if FPU is enabled and the relevant
117 	 * feature exists according to FIR register.
118 	 */
119 	if (kvm_mips_guest_has_fpu(&vcpu->arch)) {
120 		if (cpu_has_ufr)
121 			mask |= MIPS_CONF5_UFR;
122 		if (cpu_has_fre)
123 			mask |= MIPS_CONF5_FRE | MIPS_CONF5_UFE;
124 	}
125 
126 	return mask;
127 }
128 
129 /*
130  * VZ optionally allows these additional Config bits to be written by root:
131  * Config:	M, [MT]
132  * Config1:	M, [MMUSize-1, C2, MD, PC, WR, CA], FP
133  * Config2:	M
134  * Config3:	M, MSAP, [BPG], ULRI, [DSP2P, DSPP, CTXTC, ITL, LPA, VEIC,
135  *		VInt, SP, CDMM, MT, SM, TL]
136  * Config4:	M, [VTLBSizeExt, MMUSizeExt]
137  * Config5:	[MRP]
138  */
139 
140 static inline unsigned int kvm_vz_config_user_wrmask(struct kvm_vcpu *vcpu)
141 {
142 	return kvm_vz_config_guest_wrmask(vcpu) | MIPS_CONF_M;
143 }
144 
145 static inline unsigned int kvm_vz_config1_user_wrmask(struct kvm_vcpu *vcpu)
146 {
147 	unsigned int mask = kvm_vz_config1_guest_wrmask(vcpu) | MIPS_CONF_M;
148 
149 	/* Permit FPU to be present if FPU is supported */
150 	if (kvm_mips_guest_can_have_fpu(&vcpu->arch))
151 		mask |= MIPS_CONF1_FP;
152 
153 	return mask;
154 }
155 
156 static inline unsigned int kvm_vz_config2_user_wrmask(struct kvm_vcpu *vcpu)
157 {
158 	return kvm_vz_config2_guest_wrmask(vcpu) | MIPS_CONF_M;
159 }
160 
161 static inline unsigned int kvm_vz_config3_user_wrmask(struct kvm_vcpu *vcpu)
162 {
163 	unsigned int mask = kvm_vz_config3_guest_wrmask(vcpu) | MIPS_CONF_M |
164 		MIPS_CONF3_ULRI;
165 
166 	/* Permit MSA to be present if MSA is supported */
167 	if (kvm_mips_guest_can_have_msa(&vcpu->arch))
168 		mask |= MIPS_CONF3_MSA;
169 
170 	return mask;
171 }
172 
173 static inline unsigned int kvm_vz_config4_user_wrmask(struct kvm_vcpu *vcpu)
174 {
175 	return kvm_vz_config4_guest_wrmask(vcpu) | MIPS_CONF_M;
176 }
177 
178 static inline unsigned int kvm_vz_config5_user_wrmask(struct kvm_vcpu *vcpu)
179 {
180 	return kvm_vz_config5_guest_wrmask(vcpu);
181 }
182 
183 static gpa_t kvm_vz_gva_to_gpa_cb(gva_t gva)
184 {
185 	/* VZ guest has already converted gva to gpa */
186 	return gva;
187 }
188 
189 static void kvm_vz_queue_irq(struct kvm_vcpu *vcpu, unsigned int priority)
190 {
191 	set_bit(priority, &vcpu->arch.pending_exceptions);
192 	clear_bit(priority, &vcpu->arch.pending_exceptions_clr);
193 }
194 
195 static void kvm_vz_dequeue_irq(struct kvm_vcpu *vcpu, unsigned int priority)
196 {
197 	clear_bit(priority, &vcpu->arch.pending_exceptions);
198 	set_bit(priority, &vcpu->arch.pending_exceptions_clr);
199 }
200 
201 static void kvm_vz_queue_timer_int_cb(struct kvm_vcpu *vcpu)
202 {
203 	/*
204 	 * timer expiry is asynchronous to vcpu execution therefore defer guest
205 	 * cp0 accesses
206 	 */
207 	kvm_vz_queue_irq(vcpu, MIPS_EXC_INT_TIMER);
208 }
209 
210 static void kvm_vz_dequeue_timer_int_cb(struct kvm_vcpu *vcpu)
211 {
212 	/*
213 	 * timer expiry is asynchronous to vcpu execution therefore defer guest
214 	 * cp0 accesses
215 	 */
216 	kvm_vz_dequeue_irq(vcpu, MIPS_EXC_INT_TIMER);
217 }
218 
219 static void kvm_vz_queue_io_int_cb(struct kvm_vcpu *vcpu,
220 				   struct kvm_mips_interrupt *irq)
221 {
222 	int intr = (int)irq->irq;
223 
224 	/*
225 	 * interrupts are asynchronous to vcpu execution therefore defer guest
226 	 * cp0 accesses
227 	 */
228 	switch (intr) {
229 	case 2:
230 		kvm_vz_queue_irq(vcpu, MIPS_EXC_INT_IO);
231 		break;
232 
233 	case 3:
234 		kvm_vz_queue_irq(vcpu, MIPS_EXC_INT_IPI_1);
235 		break;
236 
237 	case 4:
238 		kvm_vz_queue_irq(vcpu, MIPS_EXC_INT_IPI_2);
239 		break;
240 
241 	default:
242 		break;
243 	}
244 
245 }
246 
247 static void kvm_vz_dequeue_io_int_cb(struct kvm_vcpu *vcpu,
248 				     struct kvm_mips_interrupt *irq)
249 {
250 	int intr = (int)irq->irq;
251 
252 	/*
253 	 * interrupts are asynchronous to vcpu execution therefore defer guest
254 	 * cp0 accesses
255 	 */
256 	switch (intr) {
257 	case -2:
258 		kvm_vz_dequeue_irq(vcpu, MIPS_EXC_INT_IO);
259 		break;
260 
261 	case -3:
262 		kvm_vz_dequeue_irq(vcpu, MIPS_EXC_INT_IPI_1);
263 		break;
264 
265 	case -4:
266 		kvm_vz_dequeue_irq(vcpu, MIPS_EXC_INT_IPI_2);
267 		break;
268 
269 	default:
270 		break;
271 	}
272 
273 }
274 
275 static u32 kvm_vz_priority_to_irq[MIPS_EXC_MAX] = {
276 	[MIPS_EXC_INT_TIMER] = C_IRQ5,
277 	[MIPS_EXC_INT_IO]    = C_IRQ0,
278 	[MIPS_EXC_INT_IPI_1] = C_IRQ1,
279 	[MIPS_EXC_INT_IPI_2] = C_IRQ2,
280 };
281 
282 static int kvm_vz_irq_deliver_cb(struct kvm_vcpu *vcpu, unsigned int priority,
283 				 u32 cause)
284 {
285 	u32 irq = (priority < MIPS_EXC_MAX) ?
286 		kvm_vz_priority_to_irq[priority] : 0;
287 
288 	switch (priority) {
289 	case MIPS_EXC_INT_TIMER:
290 		set_gc0_cause(C_TI);
291 		break;
292 
293 	case MIPS_EXC_INT_IO:
294 	case MIPS_EXC_INT_IPI_1:
295 	case MIPS_EXC_INT_IPI_2:
296 		if (cpu_has_guestctl2)
297 			set_c0_guestctl2(irq);
298 		else
299 			set_gc0_cause(irq);
300 		break;
301 
302 	default:
303 		break;
304 	}
305 
306 	clear_bit(priority, &vcpu->arch.pending_exceptions);
307 	return 1;
308 }
309 
310 static int kvm_vz_irq_clear_cb(struct kvm_vcpu *vcpu, unsigned int priority,
311 			       u32 cause)
312 {
313 	u32 irq = (priority < MIPS_EXC_MAX) ?
314 		kvm_vz_priority_to_irq[priority] : 0;
315 
316 	switch (priority) {
317 	case MIPS_EXC_INT_TIMER:
318 		/*
319 		 * Call to kvm_write_c0_guest_compare() clears Cause.TI in
320 		 * kvm_mips_emulate_CP0(). Explicitly clear irq associated with
321 		 * Cause.IP[IPTI] if GuestCtl2 virtual interrupt register not
322 		 * supported or if not using GuestCtl2 Hardware Clear.
323 		 */
324 		if (cpu_has_guestctl2) {
325 			if (!(read_c0_guestctl2() & (irq << 14)))
326 				clear_c0_guestctl2(irq);
327 		} else {
328 			clear_gc0_cause(irq);
329 		}
330 		break;
331 
332 	case MIPS_EXC_INT_IO:
333 	case MIPS_EXC_INT_IPI_1:
334 	case MIPS_EXC_INT_IPI_2:
335 		/* Clear GuestCtl2.VIP irq if not using Hardware Clear */
336 		if (cpu_has_guestctl2) {
337 			if (!(read_c0_guestctl2() & (irq << 14)))
338 				clear_c0_guestctl2(irq);
339 		} else {
340 			clear_gc0_cause(irq);
341 		}
342 		break;
343 
344 	default:
345 		break;
346 	}
347 
348 	clear_bit(priority, &vcpu->arch.pending_exceptions_clr);
349 	return 1;
350 }
351 
352 /*
353  * VZ guest timer handling.
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.
363  */
364 static void _kvm_vz_restore_stimer(struct kvm_vcpu *vcpu, u32 compare,
365 				   u32 cause)
366 {
367 	/*
368 	 * Avoid spurious counter interrupts by setting Guest CP0_Count to just
369 	 * after Guest CP0_Compare.
370 	 */
371 	write_c0_gtoffset(compare - read_c0_count());
372 
373 	back_to_back_c0_hazard();
374 	write_gc0_cause(cause);
375 }
376 
377 /**
378  * kvm_vz_restore_timer() - Restore guest timer state.
379  * @vcpu:	Virtual CPU.
380  *
381  * Restore soft timer state from saved context.
382  */
383 static void kvm_vz_restore_timer(struct kvm_vcpu *vcpu)
384 {
385 	struct mips_coproc *cop0 = vcpu->arch.cop0;
386 	u32 cause, compare;
387 
388 	compare = kvm_read_sw_gc0_compare(cop0);
389 	cause = kvm_read_sw_gc0_cause(cop0);
390 
391 	write_gc0_compare(compare);
392 	_kvm_vz_restore_stimer(vcpu, compare, cause);
393 }
394 
395 /**
396  * kvm_vz_save_timer() - Save guest timer state.
397  * @vcpu:	Virtual CPU.
398  *
399  * Save VZ guest timer state.
400  */
401 static void kvm_vz_save_timer(struct kvm_vcpu *vcpu)
402 {
403 	struct mips_coproc *cop0 = vcpu->arch.cop0;
404 	u32 compare, cause;
405 
406 	compare = read_gc0_compare();
407 	cause = read_gc0_cause();
408 
409 	/* save timer-related state to VCPU context */
410 	kvm_write_sw_gc0_cause(cop0, cause);
411 	kvm_write_sw_gc0_compare(cop0, compare);
412 }
413 
414 /**
415  * kvm_vz_gva_to_gpa() - Convert valid GVA to GPA.
416  * @vcpu:	KVM VCPU state.
417  * @gva:	Guest virtual address to convert.
418  * @gpa:	Output guest physical address.
419  *
420  * Convert a guest virtual address (GVA) which is valid according to the guest
421  * context, to a guest physical address (GPA).
422  *
423  * Returns:	0 on success.
424  *		-errno on failure.
425  */
426 static int kvm_vz_gva_to_gpa(struct kvm_vcpu *vcpu, unsigned long gva,
427 			     unsigned long *gpa)
428 {
429 	u32 gva32 = gva;
430 
431 	if ((long)gva == (s32)gva32) {
432 		/* Handle canonical 32-bit virtual address */
433 		if ((s32)gva32 < (s32)0xc0000000) {
434 			/* legacy unmapped KSeg0 or KSeg1 */
435 			*gpa = gva32 & 0x1fffffff;
436 			return 0;
437 		}
438 #ifdef CONFIG_64BIT
439 	} else if ((gva & 0xc000000000000000) == 0x8000000000000000) {
440 		/* XKPHYS */
441 		/*
442 		 * Traditionally fully unmapped.
443 		 * Bits 61:59 specify the CCA, which we can just mask off here.
444 		 * Bits 58:PABITS should be zero, but we shouldn't have got here
445 		 * if it wasn't.
446 		 */
447 		*gpa = gva & 0x07ffffffffffffff;
448 		return 0;
449 #endif
450 	}
451 
452 	return kvm_vz_guest_tlb_lookup(vcpu, gva, gpa);
453 }
454 
455 /**
456  * kvm_vz_badvaddr_to_gpa() - Convert GVA BadVAddr from root exception to GPA.
457  * @vcpu:	KVM VCPU state.
458  * @badvaddr:	Root BadVAddr.
459  * @gpa:	Output guest physical address.
460  *
461  * VZ implementations are permitted to report guest virtual addresses (GVA) in
462  * BadVAddr on a root exception during guest execution, instead of the more
463  * convenient guest physical addresses (GPA). When we get a GVA, this function
464  * converts it to a GPA, taking into account guest segmentation and guest TLB
465  * state.
466  *
467  * Returns:	0 on success.
468  *		-errno on failure.
469  */
470 static int kvm_vz_badvaddr_to_gpa(struct kvm_vcpu *vcpu, unsigned long badvaddr,
471 				  unsigned long *gpa)
472 {
473 	unsigned int gexccode = (vcpu->arch.host_cp0_guestctl0 &
474 				 MIPS_GCTL0_GEXC) >> MIPS_GCTL0_GEXC_SHIFT;
475 
476 	/* If BadVAddr is GPA, then all is well in the world */
477 	if (likely(gexccode == MIPS_GCTL0_GEXC_GPA)) {
478 		*gpa = badvaddr;
479 		return 0;
480 	}
481 
482 	/* Otherwise we'd expect it to be GVA ... */
483 	if (WARN(gexccode != MIPS_GCTL0_GEXC_GVA,
484 		 "Unexpected gexccode %#x\n", gexccode))
485 		return -EINVAL;
486 
487 	/* ... and we need to perform the GVA->GPA translation in software */
488 	return kvm_vz_gva_to_gpa(vcpu, badvaddr, gpa);
489 }
490 
491 static int kvm_trap_vz_no_handler(struct kvm_vcpu *vcpu)
492 {
493 	u32 *opc = (u32 *) vcpu->arch.pc;
494 	u32 cause = vcpu->arch.host_cp0_cause;
495 	u32 exccode = (cause & CAUSEF_EXCCODE) >> CAUSEB_EXCCODE;
496 	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
497 	u32 inst = 0;
498 
499 	/*
500 	 *  Fetch the instruction.
501 	 */
502 	if (cause & CAUSEF_BD)
503 		opc += 1;
504 	kvm_get_badinstr(opc, vcpu, &inst);
505 
506 	kvm_err("Exception Code: %d not handled @ PC: %p, inst: 0x%08x BadVaddr: %#lx Status: %#x\n",
507 		exccode, opc, inst, badvaddr,
508 		read_gc0_status());
509 	kvm_arch_vcpu_dump_regs(vcpu);
510 	vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
511 	return RESUME_HOST;
512 }
513 
514 static enum emulation_result kvm_vz_gpsi_cop0(union mips_instruction inst,
515 					      u32 *opc, u32 cause,
516 					      struct kvm_run *run,
517 					      struct kvm_vcpu *vcpu)
518 {
519 	struct mips_coproc *cop0 = vcpu->arch.cop0;
520 	enum emulation_result er = EMULATE_DONE;
521 	u32 rt, rd, sel;
522 	unsigned long curr_pc;
523 	unsigned long val;
524 
525 	/*
526 	 * Update PC and hold onto current PC in case there is
527 	 * an error and we want to rollback the PC
528 	 */
529 	curr_pc = vcpu->arch.pc;
530 	er = update_pc(vcpu, cause);
531 	if (er == EMULATE_FAIL)
532 		return er;
533 
534 	if (inst.co_format.co) {
535 		switch (inst.co_format.func) {
536 		case wait_op:
537 			er = kvm_mips_emul_wait(vcpu);
538 			break;
539 		default:
540 			er = EMULATE_FAIL;
541 		}
542 	} else {
543 		rt = inst.c0r_format.rt;
544 		rd = inst.c0r_format.rd;
545 		sel = inst.c0r_format.sel;
546 
547 		switch (inst.c0r_format.rs) {
548 		case dmfc_op:
549 		case mfc_op:
550 #ifdef CONFIG_KVM_MIPS_DEBUG_COP0_COUNTERS
551 			cop0->stat[rd][sel]++;
552 #endif
553 			if (rd == MIPS_CP0_COUNT &&
554 			    sel == 0) {			/* Count */
555 				val = kvm_mips_read_count(vcpu);
556 			} else if (rd == MIPS_CP0_COMPARE &&
557 				   sel == 0) {		/* Compare */
558 				val = read_gc0_compare();
559 			} else if ((rd == MIPS_CP0_PRID &&
560 				    (sel == 0 ||	/* PRid */
561 				     sel == 2 ||	/* CDMMBase */
562 				     sel == 3)) ||	/* CMGCRBase */
563 				   (rd == MIPS_CP0_STATUS &&
564 				    (sel == 2 ||	/* SRSCtl */
565 				     sel == 3)) ||	/* SRSMap */
566 				   (rd == MIPS_CP0_CONFIG &&
567 				    (sel == 7)) ||	/* Config7 */
568 				   (rd == MIPS_CP0_ERRCTL &&
569 				    (sel == 0))) {	/* ErrCtl */
570 				val = cop0->reg[rd][sel];
571 			} else {
572 				val = 0;
573 				er = EMULATE_FAIL;
574 			}
575 
576 			if (er != EMULATE_FAIL) {
577 				/* Sign extend */
578 				if (inst.c0r_format.rs == mfc_op)
579 					val = (int)val;
580 				vcpu->arch.gprs[rt] = val;
581 			}
582 
583 			trace_kvm_hwr(vcpu, (inst.c0r_format.rs == mfc_op) ?
584 					KVM_TRACE_MFC0 : KVM_TRACE_DMFC0,
585 				      KVM_TRACE_COP0(rd, sel), val);
586 			break;
587 
588 		case dmtc_op:
589 		case mtc_op:
590 #ifdef CONFIG_KVM_MIPS_DEBUG_COP0_COUNTERS
591 			cop0->stat[rd][sel]++;
592 #endif
593 			val = vcpu->arch.gprs[rt];
594 			trace_kvm_hwr(vcpu, (inst.c0r_format.rs == mtc_op) ?
595 					KVM_TRACE_MTC0 : KVM_TRACE_DMTC0,
596 				      KVM_TRACE_COP0(rd, sel), val);
597 
598 			if (rd == MIPS_CP0_COUNT &&
599 			    sel == 0) {			/* Count */
600 				kvm_mips_write_count(vcpu, vcpu->arch.gprs[rt]);
601 			} else if (rd == MIPS_CP0_COMPARE &&
602 				   sel == 0) {		/* Compare */
603 				kvm_mips_write_compare(vcpu,
604 						       vcpu->arch.gprs[rt],
605 						       true);
606 			} else if (rd == MIPS_CP0_ERRCTL &&
607 				   (sel == 0)) {	/* ErrCtl */
608 				/* ignore the written value */
609 			} else {
610 				er = EMULATE_FAIL;
611 			}
612 			break;
613 
614 		default:
615 			er = EMULATE_FAIL;
616 			break;
617 		}
618 	}
619 	/* Rollback PC only if emulation was unsuccessful */
620 	if (er == EMULATE_FAIL) {
621 		kvm_err("[%#lx]%s: unsupported cop0 instruction 0x%08x\n",
622 			curr_pc, __func__, inst.word);
623 
624 		vcpu->arch.pc = curr_pc;
625 	}
626 
627 	return er;
628 }
629 
630 static enum emulation_result kvm_vz_gpsi_cache(union mips_instruction inst,
631 					       u32 *opc, u32 cause,
632 					       struct kvm_run *run,
633 					       struct kvm_vcpu *vcpu)
634 {
635 	enum emulation_result er = EMULATE_DONE;
636 	u32 cache, op_inst, op, base;
637 	s16 offset;
638 	struct kvm_vcpu_arch *arch = &vcpu->arch;
639 	unsigned long va, curr_pc;
640 
641 	/*
642 	 * Update PC and hold onto current PC in case there is
643 	 * an error and we want to rollback the PC
644 	 */
645 	curr_pc = vcpu->arch.pc;
646 	er = update_pc(vcpu, cause);
647 	if (er == EMULATE_FAIL)
648 		return er;
649 
650 	base = inst.i_format.rs;
651 	op_inst = inst.i_format.rt;
652 	if (cpu_has_mips_r6)
653 		offset = inst.spec3_format.simmediate;
654 	else
655 		offset = inst.i_format.simmediate;
656 	cache = op_inst & CacheOp_Cache;
657 	op = op_inst & CacheOp_Op;
658 
659 	va = arch->gprs[base] + offset;
660 
661 	kvm_debug("CACHE (cache: %#x, op: %#x, base[%d]: %#lx, offset: %#x\n",
662 		  cache, op, base, arch->gprs[base], offset);
663 
664 	/* Secondary or tirtiary cache ops ignored */
665 	if (cache != Cache_I && cache != Cache_D)
666 		return EMULATE_DONE;
667 
668 	switch (op_inst) {
669 	case Index_Invalidate_I:
670 		flush_icache_line_indexed(va);
671 		return EMULATE_DONE;
672 	case Index_Writeback_Inv_D:
673 		flush_dcache_line_indexed(va);
674 		return EMULATE_DONE;
675 	default:
676 		break;
677 	};
678 
679 	kvm_err("@ %#lx/%#lx CACHE (cache: %#x, op: %#x, base[%d]: %#lx, offset: %#x\n",
680 		curr_pc, vcpu->arch.gprs[31], cache, op, base, arch->gprs[base],
681 		offset);
682 	/* Rollback PC */
683 	vcpu->arch.pc = curr_pc;
684 
685 	return EMULATE_FAIL;
686 }
687 
688 static enum emulation_result kvm_trap_vz_handle_gpsi(u32 cause, u32 *opc,
689 						     struct kvm_vcpu *vcpu)
690 {
691 	enum emulation_result er = EMULATE_DONE;
692 	struct kvm_vcpu_arch *arch = &vcpu->arch;
693 	struct kvm_run *run = vcpu->run;
694 	union mips_instruction inst;
695 	int rd, rt, sel;
696 	int err;
697 
698 	/*
699 	 *  Fetch the instruction.
700 	 */
701 	if (cause & CAUSEF_BD)
702 		opc += 1;
703 	err = kvm_get_badinstr(opc, vcpu, &inst.word);
704 	if (err)
705 		return EMULATE_FAIL;
706 
707 	switch (inst.r_format.opcode) {
708 	case cop0_op:
709 		er = kvm_vz_gpsi_cop0(inst, opc, cause, run, vcpu);
710 		break;
711 #ifndef CONFIG_CPU_MIPSR6
712 	case cache_op:
713 		trace_kvm_exit(vcpu, KVM_TRACE_EXIT_CACHE);
714 		er = kvm_vz_gpsi_cache(inst, opc, cause, run, vcpu);
715 		break;
716 #endif
717 	case spec3_op:
718 		switch (inst.spec3_format.func) {
719 #ifdef CONFIG_CPU_MIPSR6
720 		case cache6_op:
721 			trace_kvm_exit(vcpu, KVM_TRACE_EXIT_CACHE);
722 			er = kvm_vz_gpsi_cache(inst, opc, cause, run, vcpu);
723 			break;
724 #endif
725 		case rdhwr_op:
726 			if (inst.r_format.rs || (inst.r_format.re >> 3))
727 				goto unknown;
728 
729 			rd = inst.r_format.rd;
730 			rt = inst.r_format.rt;
731 			sel = inst.r_format.re & 0x7;
732 
733 			switch (rd) {
734 			case MIPS_HWR_CC:	/* Read count register */
735 				arch->gprs[rt] =
736 					(long)(int)kvm_mips_read_count(vcpu);
737 				break;
738 			default:
739 				trace_kvm_hwr(vcpu, KVM_TRACE_RDHWR,
740 					      KVM_TRACE_HWR(rd, sel), 0);
741 				goto unknown;
742 			};
743 
744 			trace_kvm_hwr(vcpu, KVM_TRACE_RDHWR,
745 				      KVM_TRACE_HWR(rd, sel), arch->gprs[rt]);
746 
747 			er = update_pc(vcpu, cause);
748 			break;
749 		default:
750 			goto unknown;
751 		};
752 		break;
753 unknown:
754 
755 	default:
756 		kvm_err("GPSI exception not supported (%p/%#x)\n",
757 				opc, inst.word);
758 		kvm_arch_vcpu_dump_regs(vcpu);
759 		er = EMULATE_FAIL;
760 		break;
761 	}
762 
763 	return er;
764 }
765 
766 static enum emulation_result kvm_trap_vz_handle_gsfc(u32 cause, u32 *opc,
767 						     struct kvm_vcpu *vcpu)
768 {
769 	enum emulation_result er = EMULATE_DONE;
770 	struct kvm_vcpu_arch *arch = &vcpu->arch;
771 	union mips_instruction inst;
772 	int err;
773 
774 	/*
775 	 *  Fetch the instruction.
776 	 */
777 	if (cause & CAUSEF_BD)
778 		opc += 1;
779 	err = kvm_get_badinstr(opc, vcpu, &inst.word);
780 	if (err)
781 		return EMULATE_FAIL;
782 
783 	/* complete MTC0 on behalf of guest and advance EPC */
784 	if (inst.c0r_format.opcode == cop0_op &&
785 	    inst.c0r_format.rs == mtc_op &&
786 	    inst.c0r_format.z == 0) {
787 		int rt = inst.c0r_format.rt;
788 		int rd = inst.c0r_format.rd;
789 		int sel = inst.c0r_format.sel;
790 		unsigned int val = arch->gprs[rt];
791 		unsigned int old_val, change;
792 
793 		trace_kvm_hwr(vcpu, KVM_TRACE_MTC0, KVM_TRACE_COP0(rd, sel),
794 			      val);
795 
796 		if ((rd == MIPS_CP0_STATUS) && (sel == 0)) {
797 			/* FR bit should read as zero if no FPU */
798 			if (!kvm_mips_guest_has_fpu(&vcpu->arch))
799 				val &= ~(ST0_CU1 | ST0_FR);
800 
801 			/*
802 			 * Also don't allow FR to be set if host doesn't support
803 			 * it.
804 			 */
805 			if (!(boot_cpu_data.fpu_id & MIPS_FPIR_F64))
806 				val &= ~ST0_FR;
807 
808 			old_val = read_gc0_status();
809 			change = val ^ old_val;
810 
811 			if (change & ST0_FR) {
812 				/*
813 				 * FPU and Vector register state is made
814 				 * UNPREDICTABLE by a change of FR, so don't
815 				 * even bother saving it.
816 				 */
817 				kvm_drop_fpu(vcpu);
818 			}
819 
820 			/*
821 			 * If MSA state is already live, it is undefined how it
822 			 * interacts with FR=0 FPU state, and we don't want to
823 			 * hit reserved instruction exceptions trying to save
824 			 * the MSA state later when CU=1 && FR=1, so play it
825 			 * safe and save it first.
826 			 */
827 			if (change & ST0_CU1 && !(val & ST0_FR) &&
828 			    vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA)
829 				kvm_lose_fpu(vcpu);
830 
831 			write_gc0_status(val);
832 		} else if ((rd == MIPS_CP0_CAUSE) && (sel == 0)) {
833 			u32 old_cause = read_gc0_cause();
834 			u32 change = old_cause ^ val;
835 
836 			/* DC bit enabling/disabling timer? */
837 			if (change & CAUSEF_DC) {
838 				if (val & CAUSEF_DC)
839 					kvm_mips_count_disable_cause(vcpu);
840 				else
841 					kvm_mips_count_enable_cause(vcpu);
842 			}
843 
844 			/* Only certain bits are RW to the guest */
845 			change &= (CAUSEF_DC | CAUSEF_IV | CAUSEF_WP |
846 				   CAUSEF_IP0 | CAUSEF_IP1);
847 
848 			/* WP can only be cleared */
849 			change &= ~CAUSEF_WP | old_cause;
850 
851 			write_gc0_cause(old_cause ^ change);
852 		} else if ((rd == MIPS_CP0_STATUS) && (sel == 1)) { /* IntCtl */
853 			write_gc0_intctl(val);
854 		} else if ((rd == MIPS_CP0_CONFIG) && (sel == 5)) {
855 			old_val = read_gc0_config5();
856 			change = val ^ old_val;
857 			/* Handle changes in FPU/MSA modes */
858 			preempt_disable();
859 
860 			/*
861 			 * Propagate FRE changes immediately if the FPU
862 			 * context is already loaded.
863 			 */
864 			if (change & MIPS_CONF5_FRE &&
865 			    vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU)
866 				change_c0_config5(MIPS_CONF5_FRE, val);
867 
868 			preempt_enable();
869 
870 			val = old_val ^
871 				(change & kvm_vz_config5_guest_wrmask(vcpu));
872 			write_gc0_config5(val);
873 		} else {
874 			kvm_err("Handle GSFC, unsupported field change @ %p: %#x\n",
875 			    opc, inst.word);
876 			er = EMULATE_FAIL;
877 		}
878 
879 		if (er != EMULATE_FAIL)
880 			er = update_pc(vcpu, cause);
881 	} else {
882 		kvm_err("Handle GSFC, unrecognized instruction @ %p: %#x\n",
883 			opc, inst.word);
884 		er = EMULATE_FAIL;
885 	}
886 
887 	return er;
888 }
889 
890 static enum emulation_result kvm_trap_vz_handle_hc(u32 cause, u32 *opc,
891 						   struct kvm_vcpu *vcpu)
892 {
893 	enum emulation_result er;
894 	union mips_instruction inst;
895 	unsigned long curr_pc;
896 	int err;
897 
898 	if (cause & CAUSEF_BD)
899 		opc += 1;
900 	err = kvm_get_badinstr(opc, vcpu, &inst.word);
901 	if (err)
902 		return EMULATE_FAIL;
903 
904 	/*
905 	 * Update PC and hold onto current PC in case there is
906 	 * an error and we want to rollback the PC
907 	 */
908 	curr_pc = vcpu->arch.pc;
909 	er = update_pc(vcpu, cause);
910 	if (er == EMULATE_FAIL)
911 		return er;
912 
913 	er = kvm_mips_emul_hypcall(vcpu, inst);
914 	if (er == EMULATE_FAIL)
915 		vcpu->arch.pc = curr_pc;
916 
917 	return er;
918 }
919 
920 static enum emulation_result kvm_trap_vz_no_handler_guest_exit(u32 gexccode,
921 							u32 cause,
922 							u32 *opc,
923 							struct kvm_vcpu *vcpu)
924 {
925 	u32 inst;
926 
927 	/*
928 	 *  Fetch the instruction.
929 	 */
930 	if (cause & CAUSEF_BD)
931 		opc += 1;
932 	kvm_get_badinstr(opc, vcpu, &inst);
933 
934 	kvm_err("Guest Exception Code: %d not yet handled @ PC: %p, inst: 0x%08x  Status: %#x\n",
935 		gexccode, opc, inst, read_gc0_status());
936 
937 	return EMULATE_FAIL;
938 }
939 
940 static int kvm_trap_vz_handle_guest_exit(struct kvm_vcpu *vcpu)
941 {
942 	u32 *opc = (u32 *) vcpu->arch.pc;
943 	u32 cause = vcpu->arch.host_cp0_cause;
944 	enum emulation_result er = EMULATE_DONE;
945 	u32 gexccode = (vcpu->arch.host_cp0_guestctl0 &
946 			MIPS_GCTL0_GEXC) >> MIPS_GCTL0_GEXC_SHIFT;
947 	int ret = RESUME_GUEST;
948 
949 	trace_kvm_exit(vcpu, KVM_TRACE_EXIT_GEXCCODE_BASE + gexccode);
950 	switch (gexccode) {
951 	case MIPS_GCTL0_GEXC_GPSI:
952 		++vcpu->stat.vz_gpsi_exits;
953 		er = kvm_trap_vz_handle_gpsi(cause, opc, vcpu);
954 		break;
955 	case MIPS_GCTL0_GEXC_GSFC:
956 		++vcpu->stat.vz_gsfc_exits;
957 		er = kvm_trap_vz_handle_gsfc(cause, opc, vcpu);
958 		break;
959 	case MIPS_GCTL0_GEXC_HC:
960 		++vcpu->stat.vz_hc_exits;
961 		er = kvm_trap_vz_handle_hc(cause, opc, vcpu);
962 		break;
963 	case MIPS_GCTL0_GEXC_GRR:
964 		++vcpu->stat.vz_grr_exits;
965 		er = kvm_trap_vz_no_handler_guest_exit(gexccode, cause, opc,
966 						       vcpu);
967 		break;
968 	case MIPS_GCTL0_GEXC_GVA:
969 		++vcpu->stat.vz_gva_exits;
970 		er = kvm_trap_vz_no_handler_guest_exit(gexccode, cause, opc,
971 						       vcpu);
972 		break;
973 	case MIPS_GCTL0_GEXC_GHFC:
974 		++vcpu->stat.vz_ghfc_exits;
975 		er = kvm_trap_vz_no_handler_guest_exit(gexccode, cause, opc,
976 						       vcpu);
977 		break;
978 	case MIPS_GCTL0_GEXC_GPA:
979 		++vcpu->stat.vz_gpa_exits;
980 		er = kvm_trap_vz_no_handler_guest_exit(gexccode, cause, opc,
981 						       vcpu);
982 		break;
983 	default:
984 		++vcpu->stat.vz_resvd_exits;
985 		er = kvm_trap_vz_no_handler_guest_exit(gexccode, cause, opc,
986 						       vcpu);
987 		break;
988 
989 	}
990 
991 	if (er == EMULATE_DONE) {
992 		ret = RESUME_GUEST;
993 	} else if (er == EMULATE_HYPERCALL) {
994 		ret = kvm_mips_handle_hypcall(vcpu);
995 	} else {
996 		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
997 		ret = RESUME_HOST;
998 	}
999 	return ret;
1000 }
1001 
1002 /**
1003  * kvm_trap_vz_handle_cop_unusuable() - Guest used unusable coprocessor.
1004  * @vcpu:	Virtual CPU context.
1005  *
1006  * Handle when the guest attempts to use a coprocessor which hasn't been allowed
1007  * by the root context.
1008  */
1009 static int kvm_trap_vz_handle_cop_unusable(struct kvm_vcpu *vcpu)
1010 {
1011 	struct kvm_run *run = vcpu->run;
1012 	u32 cause = vcpu->arch.host_cp0_cause;
1013 	enum emulation_result er = EMULATE_FAIL;
1014 	int ret = RESUME_GUEST;
1015 
1016 	if (((cause & CAUSEF_CE) >> CAUSEB_CE) == 1) {
1017 		/*
1018 		 * If guest FPU not present, the FPU operation should have been
1019 		 * treated as a reserved instruction!
1020 		 * If FPU already in use, we shouldn't get this at all.
1021 		 */
1022 		if (WARN_ON(!kvm_mips_guest_has_fpu(&vcpu->arch) ||
1023 			    vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU)) {
1024 			preempt_enable();
1025 			return EMULATE_FAIL;
1026 		}
1027 
1028 		kvm_own_fpu(vcpu);
1029 		er = EMULATE_DONE;
1030 	}
1031 	/* other coprocessors not handled */
1032 
1033 	switch (er) {
1034 	case EMULATE_DONE:
1035 		ret = RESUME_GUEST;
1036 		break;
1037 
1038 	case EMULATE_FAIL:
1039 		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1040 		ret = RESUME_HOST;
1041 		break;
1042 
1043 	default:
1044 		BUG();
1045 	}
1046 	return ret;
1047 }
1048 
1049 /**
1050  * kvm_trap_vz_handle_msa_disabled() - Guest used MSA while disabled in root.
1051  * @vcpu:	Virtual CPU context.
1052  *
1053  * Handle when the guest attempts to use MSA when it is disabled in the root
1054  * context.
1055  */
1056 static int kvm_trap_vz_handle_msa_disabled(struct kvm_vcpu *vcpu)
1057 {
1058 	struct kvm_run *run = vcpu->run;
1059 
1060 	/*
1061 	 * If MSA not present or not exposed to guest or FR=0, the MSA operation
1062 	 * should have been treated as a reserved instruction!
1063 	 * Same if CU1=1, FR=0.
1064 	 * If MSA already in use, we shouldn't get this at all.
1065 	 */
1066 	if (!kvm_mips_guest_has_msa(&vcpu->arch) ||
1067 	    (read_gc0_status() & (ST0_CU1 | ST0_FR)) == ST0_CU1 ||
1068 	    !(read_gc0_config5() & MIPS_CONF5_MSAEN) ||
1069 	    vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1070 		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1071 		return RESUME_HOST;
1072 	}
1073 
1074 	kvm_own_msa(vcpu);
1075 
1076 	return RESUME_GUEST;
1077 }
1078 
1079 static int kvm_trap_vz_handle_tlb_ld_miss(struct kvm_vcpu *vcpu)
1080 {
1081 	struct kvm_run *run = vcpu->run;
1082 	u32 *opc = (u32 *) vcpu->arch.pc;
1083 	u32 cause = vcpu->arch.host_cp0_cause;
1084 	ulong badvaddr = vcpu->arch.host_cp0_badvaddr;
1085 	union mips_instruction inst;
1086 	enum emulation_result er = EMULATE_DONE;
1087 	int err, ret = RESUME_GUEST;
1088 
1089 	if (kvm_mips_handle_vz_root_tlb_fault(badvaddr, vcpu, false)) {
1090 		/* A code fetch fault doesn't count as an MMIO */
1091 		if (kvm_is_ifetch_fault(&vcpu->arch)) {
1092 			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1093 			return RESUME_HOST;
1094 		}
1095 
1096 		/* Fetch the instruction */
1097 		if (cause & CAUSEF_BD)
1098 			opc += 1;
1099 		err = kvm_get_badinstr(opc, vcpu, &inst.word);
1100 		if (err) {
1101 			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1102 			return RESUME_HOST;
1103 		}
1104 
1105 		/* Treat as MMIO */
1106 		er = kvm_mips_emulate_load(inst, cause, run, vcpu);
1107 		if (er == EMULATE_FAIL) {
1108 			kvm_err("Guest Emulate Load from MMIO space failed: PC: %p, BadVaddr: %#lx\n",
1109 				opc, badvaddr);
1110 			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1111 		}
1112 	}
1113 
1114 	if (er == EMULATE_DONE) {
1115 		ret = RESUME_GUEST;
1116 	} else if (er == EMULATE_DO_MMIO) {
1117 		run->exit_reason = KVM_EXIT_MMIO;
1118 		ret = RESUME_HOST;
1119 	} else {
1120 		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1121 		ret = RESUME_HOST;
1122 	}
1123 	return ret;
1124 }
1125 
1126 static int kvm_trap_vz_handle_tlb_st_miss(struct kvm_vcpu *vcpu)
1127 {
1128 	struct kvm_run *run = vcpu->run;
1129 	u32 *opc = (u32 *) vcpu->arch.pc;
1130 	u32 cause = vcpu->arch.host_cp0_cause;
1131 	ulong badvaddr = vcpu->arch.host_cp0_badvaddr;
1132 	union mips_instruction inst;
1133 	enum emulation_result er = EMULATE_DONE;
1134 	int err;
1135 	int ret = RESUME_GUEST;
1136 
1137 	/* Just try the access again if we couldn't do the translation */
1138 	if (kvm_vz_badvaddr_to_gpa(vcpu, badvaddr, &badvaddr))
1139 		return RESUME_GUEST;
1140 	vcpu->arch.host_cp0_badvaddr = badvaddr;
1141 
1142 	if (kvm_mips_handle_vz_root_tlb_fault(badvaddr, vcpu, true)) {
1143 		/* Fetch the instruction */
1144 		if (cause & CAUSEF_BD)
1145 			opc += 1;
1146 		err = kvm_get_badinstr(opc, vcpu, &inst.word);
1147 		if (err) {
1148 			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1149 			return RESUME_HOST;
1150 		}
1151 
1152 		/* Treat as MMIO */
1153 		er = kvm_mips_emulate_store(inst, cause, run, vcpu);
1154 		if (er == EMULATE_FAIL) {
1155 			kvm_err("Guest Emulate Store to MMIO space failed: PC: %p, BadVaddr: %#lx\n",
1156 				opc, badvaddr);
1157 			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1158 		}
1159 	}
1160 
1161 	if (er == EMULATE_DONE) {
1162 		ret = RESUME_GUEST;
1163 	} else if (er == EMULATE_DO_MMIO) {
1164 		run->exit_reason = KVM_EXIT_MMIO;
1165 		ret = RESUME_HOST;
1166 	} else {
1167 		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1168 		ret = RESUME_HOST;
1169 	}
1170 	return ret;
1171 }
1172 
1173 static u64 kvm_vz_get_one_regs[] = {
1174 	KVM_REG_MIPS_CP0_INDEX,
1175 	KVM_REG_MIPS_CP0_ENTRYLO0,
1176 	KVM_REG_MIPS_CP0_ENTRYLO1,
1177 	KVM_REG_MIPS_CP0_CONTEXT,
1178 	KVM_REG_MIPS_CP0_PAGEMASK,
1179 	KVM_REG_MIPS_CP0_PAGEGRAIN,
1180 	KVM_REG_MIPS_CP0_WIRED,
1181 	KVM_REG_MIPS_CP0_HWRENA,
1182 	KVM_REG_MIPS_CP0_BADVADDR,
1183 	KVM_REG_MIPS_CP0_COUNT,
1184 	KVM_REG_MIPS_CP0_ENTRYHI,
1185 	KVM_REG_MIPS_CP0_COMPARE,
1186 	KVM_REG_MIPS_CP0_STATUS,
1187 	KVM_REG_MIPS_CP0_INTCTL,
1188 	KVM_REG_MIPS_CP0_CAUSE,
1189 	KVM_REG_MIPS_CP0_EPC,
1190 	KVM_REG_MIPS_CP0_PRID,
1191 	KVM_REG_MIPS_CP0_EBASE,
1192 	KVM_REG_MIPS_CP0_CONFIG,
1193 	KVM_REG_MIPS_CP0_CONFIG1,
1194 	KVM_REG_MIPS_CP0_CONFIG2,
1195 	KVM_REG_MIPS_CP0_CONFIG3,
1196 	KVM_REG_MIPS_CP0_CONFIG4,
1197 	KVM_REG_MIPS_CP0_CONFIG5,
1198 #ifdef CONFIG_64BIT
1199 	KVM_REG_MIPS_CP0_XCONTEXT,
1200 #endif
1201 	KVM_REG_MIPS_CP0_ERROREPC,
1202 
1203 	KVM_REG_MIPS_COUNT_CTL,
1204 	KVM_REG_MIPS_COUNT_RESUME,
1205 	KVM_REG_MIPS_COUNT_HZ,
1206 };
1207 
1208 static u64 kvm_vz_get_one_regs_kscratch[] = {
1209 	KVM_REG_MIPS_CP0_KSCRATCH1,
1210 	KVM_REG_MIPS_CP0_KSCRATCH2,
1211 	KVM_REG_MIPS_CP0_KSCRATCH3,
1212 	KVM_REG_MIPS_CP0_KSCRATCH4,
1213 	KVM_REG_MIPS_CP0_KSCRATCH5,
1214 	KVM_REG_MIPS_CP0_KSCRATCH6,
1215 };
1216 
1217 static unsigned long kvm_vz_num_regs(struct kvm_vcpu *vcpu)
1218 {
1219 	unsigned long ret;
1220 
1221 	ret = ARRAY_SIZE(kvm_vz_get_one_regs);
1222 	if (cpu_guest_has_userlocal)
1223 		++ret;
1224 	ret += __arch_hweight8(cpu_data[0].guest.kscratch_mask);
1225 
1226 	return ret;
1227 }
1228 
1229 static int kvm_vz_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices)
1230 {
1231 	u64 index;
1232 	unsigned int i;
1233 
1234 	if (copy_to_user(indices, kvm_vz_get_one_regs,
1235 			 sizeof(kvm_vz_get_one_regs)))
1236 		return -EFAULT;
1237 	indices += ARRAY_SIZE(kvm_vz_get_one_regs);
1238 
1239 	if (cpu_guest_has_userlocal) {
1240 		index = KVM_REG_MIPS_CP0_USERLOCAL;
1241 		if (copy_to_user(indices, &index, sizeof(index)))
1242 			return -EFAULT;
1243 		++indices;
1244 	}
1245 	for (i = 0; i < 6; ++i) {
1246 		if (!cpu_guest_has_kscr(i + 2))
1247 			continue;
1248 
1249 		if (copy_to_user(indices, &kvm_vz_get_one_regs_kscratch[i],
1250 				 sizeof(kvm_vz_get_one_regs_kscratch[i])))
1251 			return -EFAULT;
1252 		++indices;
1253 	}
1254 
1255 	return 0;
1256 }
1257 
1258 static inline s64 entrylo_kvm_to_user(unsigned long v)
1259 {
1260 	s64 mask, ret = v;
1261 
1262 	if (BITS_PER_LONG == 32) {
1263 		/*
1264 		 * KVM API exposes 64-bit version of the register, so move the
1265 		 * RI/XI bits up into place.
1266 		 */
1267 		mask = MIPS_ENTRYLO_RI | MIPS_ENTRYLO_XI;
1268 		ret &= ~mask;
1269 		ret |= ((s64)v & mask) << 32;
1270 	}
1271 	return ret;
1272 }
1273 
1274 static inline unsigned long entrylo_user_to_kvm(s64 v)
1275 {
1276 	unsigned long mask, ret = v;
1277 
1278 	if (BITS_PER_LONG == 32) {
1279 		/*
1280 		 * KVM API exposes 64-bit versiono of the register, so move the
1281 		 * RI/XI bits down into place.
1282 		 */
1283 		mask = MIPS_ENTRYLO_RI | MIPS_ENTRYLO_XI;
1284 		ret &= ~mask;
1285 		ret |= (v >> 32) & mask;
1286 	}
1287 	return ret;
1288 }
1289 
1290 static int kvm_vz_get_one_reg(struct kvm_vcpu *vcpu,
1291 			      const struct kvm_one_reg *reg,
1292 			      s64 *v)
1293 {
1294 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1295 	unsigned int idx;
1296 
1297 	switch (reg->id) {
1298 	case KVM_REG_MIPS_CP0_INDEX:
1299 		*v = (long)read_gc0_index();
1300 		break;
1301 	case KVM_REG_MIPS_CP0_ENTRYLO0:
1302 		*v = entrylo_kvm_to_user(read_gc0_entrylo0());
1303 		break;
1304 	case KVM_REG_MIPS_CP0_ENTRYLO1:
1305 		*v = entrylo_kvm_to_user(read_gc0_entrylo1());
1306 		break;
1307 	case KVM_REG_MIPS_CP0_CONTEXT:
1308 		*v = (long)read_gc0_context();
1309 		break;
1310 	case KVM_REG_MIPS_CP0_USERLOCAL:
1311 		if (!cpu_guest_has_userlocal)
1312 			return -EINVAL;
1313 		*v = read_gc0_userlocal();
1314 		break;
1315 	case KVM_REG_MIPS_CP0_PAGEMASK:
1316 		*v = (long)read_gc0_pagemask();
1317 		break;
1318 	case KVM_REG_MIPS_CP0_PAGEGRAIN:
1319 		*v = (long)read_gc0_pagegrain();
1320 		break;
1321 	case KVM_REG_MIPS_CP0_WIRED:
1322 		*v = (long)read_gc0_wired();
1323 		break;
1324 	case KVM_REG_MIPS_CP0_HWRENA:
1325 		*v = (long)read_gc0_hwrena();
1326 		break;
1327 	case KVM_REG_MIPS_CP0_BADVADDR:
1328 		*v = (long)read_gc0_badvaddr();
1329 		break;
1330 	case KVM_REG_MIPS_CP0_COUNT:
1331 		*v = kvm_mips_read_count(vcpu);
1332 		break;
1333 	case KVM_REG_MIPS_CP0_ENTRYHI:
1334 		*v = (long)read_gc0_entryhi();
1335 		break;
1336 	case KVM_REG_MIPS_CP0_COMPARE:
1337 		*v = (long)read_gc0_compare();
1338 		break;
1339 	case KVM_REG_MIPS_CP0_STATUS:
1340 		*v = (long)read_gc0_status();
1341 		break;
1342 	case KVM_REG_MIPS_CP0_INTCTL:
1343 		*v = read_gc0_intctl();
1344 		break;
1345 	case KVM_REG_MIPS_CP0_CAUSE:
1346 		*v = (long)read_gc0_cause();
1347 		break;
1348 	case KVM_REG_MIPS_CP0_EPC:
1349 		*v = (long)read_gc0_epc();
1350 		break;
1351 	case KVM_REG_MIPS_CP0_PRID:
1352 		*v = (long)kvm_read_c0_guest_prid(cop0);
1353 		break;
1354 	case KVM_REG_MIPS_CP0_EBASE:
1355 		*v = kvm_vz_read_gc0_ebase();
1356 		break;
1357 	case KVM_REG_MIPS_CP0_CONFIG:
1358 		*v = read_gc0_config();
1359 		break;
1360 	case KVM_REG_MIPS_CP0_CONFIG1:
1361 		if (!cpu_guest_has_conf1)
1362 			return -EINVAL;
1363 		*v = read_gc0_config1();
1364 		break;
1365 	case KVM_REG_MIPS_CP0_CONFIG2:
1366 		if (!cpu_guest_has_conf2)
1367 			return -EINVAL;
1368 		*v = read_gc0_config2();
1369 		break;
1370 	case KVM_REG_MIPS_CP0_CONFIG3:
1371 		if (!cpu_guest_has_conf3)
1372 			return -EINVAL;
1373 		*v = read_gc0_config3();
1374 		break;
1375 	case KVM_REG_MIPS_CP0_CONFIG4:
1376 		if (!cpu_guest_has_conf4)
1377 			return -EINVAL;
1378 		*v = read_gc0_config4();
1379 		break;
1380 	case KVM_REG_MIPS_CP0_CONFIG5:
1381 		if (!cpu_guest_has_conf5)
1382 			return -EINVAL;
1383 		*v = read_gc0_config5();
1384 		break;
1385 #ifdef CONFIG_64BIT
1386 	case KVM_REG_MIPS_CP0_XCONTEXT:
1387 		*v = read_gc0_xcontext();
1388 		break;
1389 #endif
1390 	case KVM_REG_MIPS_CP0_ERROREPC:
1391 		*v = (long)read_gc0_errorepc();
1392 		break;
1393 	case KVM_REG_MIPS_CP0_KSCRATCH1 ... KVM_REG_MIPS_CP0_KSCRATCH6:
1394 		idx = reg->id - KVM_REG_MIPS_CP0_KSCRATCH1 + 2;
1395 		if (!cpu_guest_has_kscr(idx))
1396 			return -EINVAL;
1397 		switch (idx) {
1398 		case 2:
1399 			*v = (long)read_gc0_kscratch1();
1400 			break;
1401 		case 3:
1402 			*v = (long)read_gc0_kscratch2();
1403 			break;
1404 		case 4:
1405 			*v = (long)read_gc0_kscratch3();
1406 			break;
1407 		case 5:
1408 			*v = (long)read_gc0_kscratch4();
1409 			break;
1410 		case 6:
1411 			*v = (long)read_gc0_kscratch5();
1412 			break;
1413 		case 7:
1414 			*v = (long)read_gc0_kscratch6();
1415 			break;
1416 		}
1417 		break;
1418 	case KVM_REG_MIPS_COUNT_CTL:
1419 		*v = vcpu->arch.count_ctl;
1420 		break;
1421 	case KVM_REG_MIPS_COUNT_RESUME:
1422 		*v = ktime_to_ns(vcpu->arch.count_resume);
1423 		break;
1424 	case KVM_REG_MIPS_COUNT_HZ:
1425 		*v = vcpu->arch.count_hz;
1426 		break;
1427 	default:
1428 		return -EINVAL;
1429 	}
1430 	return 0;
1431 }
1432 
1433 static int kvm_vz_set_one_reg(struct kvm_vcpu *vcpu,
1434 			      const struct kvm_one_reg *reg,
1435 			      s64 v)
1436 {
1437 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1438 	unsigned int idx;
1439 	int ret = 0;
1440 	unsigned int cur, change;
1441 
1442 	switch (reg->id) {
1443 	case KVM_REG_MIPS_CP0_INDEX:
1444 		write_gc0_index(v);
1445 		break;
1446 	case KVM_REG_MIPS_CP0_ENTRYLO0:
1447 		write_gc0_entrylo0(entrylo_user_to_kvm(v));
1448 		break;
1449 	case KVM_REG_MIPS_CP0_ENTRYLO1:
1450 		write_gc0_entrylo1(entrylo_user_to_kvm(v));
1451 		break;
1452 	case KVM_REG_MIPS_CP0_CONTEXT:
1453 		write_gc0_context(v);
1454 		break;
1455 	case KVM_REG_MIPS_CP0_USERLOCAL:
1456 		if (!cpu_guest_has_userlocal)
1457 			return -EINVAL;
1458 		write_gc0_userlocal(v);
1459 		break;
1460 	case KVM_REG_MIPS_CP0_PAGEMASK:
1461 		write_gc0_pagemask(v);
1462 		break;
1463 	case KVM_REG_MIPS_CP0_PAGEGRAIN:
1464 		write_gc0_pagegrain(v);
1465 		break;
1466 	case KVM_REG_MIPS_CP0_WIRED:
1467 		change_gc0_wired(MIPSR6_WIRED_WIRED, v);
1468 		break;
1469 	case KVM_REG_MIPS_CP0_HWRENA:
1470 		write_gc0_hwrena(v);
1471 		break;
1472 	case KVM_REG_MIPS_CP0_BADVADDR:
1473 		write_gc0_badvaddr(v);
1474 		break;
1475 	case KVM_REG_MIPS_CP0_COUNT:
1476 		kvm_mips_write_count(vcpu, v);
1477 		break;
1478 	case KVM_REG_MIPS_CP0_ENTRYHI:
1479 		write_gc0_entryhi(v);
1480 		break;
1481 	case KVM_REG_MIPS_CP0_COMPARE:
1482 		kvm_mips_write_compare(vcpu, v, false);
1483 		break;
1484 	case KVM_REG_MIPS_CP0_STATUS:
1485 		write_gc0_status(v);
1486 		break;
1487 	case KVM_REG_MIPS_CP0_INTCTL:
1488 		write_gc0_intctl(v);
1489 		break;
1490 	case KVM_REG_MIPS_CP0_CAUSE:
1491 		/*
1492 		 * If the timer is stopped or started (DC bit) it must look
1493 		 * atomic with changes to the timer interrupt pending bit (TI).
1494 		 * A timer interrupt should not happen in between.
1495 		 */
1496 		if ((read_gc0_cause() ^ v) & CAUSEF_DC) {
1497 			if (v & CAUSEF_DC) {
1498 				/* disable timer first */
1499 				kvm_mips_count_disable_cause(vcpu);
1500 				change_gc0_cause((u32)~CAUSEF_DC, v);
1501 			} else {
1502 				/* enable timer last */
1503 				change_gc0_cause((u32)~CAUSEF_DC, v);
1504 				kvm_mips_count_enable_cause(vcpu);
1505 			}
1506 		} else {
1507 			write_gc0_cause(v);
1508 		}
1509 		break;
1510 	case KVM_REG_MIPS_CP0_EPC:
1511 		write_gc0_epc(v);
1512 		break;
1513 	case KVM_REG_MIPS_CP0_PRID:
1514 		kvm_write_c0_guest_prid(cop0, v);
1515 		break;
1516 	case KVM_REG_MIPS_CP0_EBASE:
1517 		kvm_vz_write_gc0_ebase(v);
1518 		break;
1519 	case KVM_REG_MIPS_CP0_CONFIG:
1520 		cur = read_gc0_config();
1521 		change = (cur ^ v) & kvm_vz_config_user_wrmask(vcpu);
1522 		if (change) {
1523 			v = cur ^ change;
1524 			write_gc0_config(v);
1525 		}
1526 		break;
1527 	case KVM_REG_MIPS_CP0_CONFIG1:
1528 		if (!cpu_guest_has_conf1)
1529 			break;
1530 		cur = read_gc0_config1();
1531 		change = (cur ^ v) & kvm_vz_config1_user_wrmask(vcpu);
1532 		if (change) {
1533 			v = cur ^ change;
1534 			write_gc0_config1(v);
1535 		}
1536 		break;
1537 	case KVM_REG_MIPS_CP0_CONFIG2:
1538 		if (!cpu_guest_has_conf2)
1539 			break;
1540 		cur = read_gc0_config2();
1541 		change = (cur ^ v) & kvm_vz_config2_user_wrmask(vcpu);
1542 		if (change) {
1543 			v = cur ^ change;
1544 			write_gc0_config2(v);
1545 		}
1546 		break;
1547 	case KVM_REG_MIPS_CP0_CONFIG3:
1548 		if (!cpu_guest_has_conf3)
1549 			break;
1550 		cur = read_gc0_config3();
1551 		change = (cur ^ v) & kvm_vz_config3_user_wrmask(vcpu);
1552 		if (change) {
1553 			v = cur ^ change;
1554 			write_gc0_config3(v);
1555 		}
1556 		break;
1557 	case KVM_REG_MIPS_CP0_CONFIG4:
1558 		if (!cpu_guest_has_conf4)
1559 			break;
1560 		cur = read_gc0_config4();
1561 		change = (cur ^ v) & kvm_vz_config4_user_wrmask(vcpu);
1562 		if (change) {
1563 			v = cur ^ change;
1564 			write_gc0_config4(v);
1565 		}
1566 		break;
1567 	case KVM_REG_MIPS_CP0_CONFIG5:
1568 		if (!cpu_guest_has_conf5)
1569 			break;
1570 		cur = read_gc0_config5();
1571 		change = (cur ^ v) & kvm_vz_config5_user_wrmask(vcpu);
1572 		if (change) {
1573 			v = cur ^ change;
1574 			write_gc0_config5(v);
1575 		}
1576 		break;
1577 #ifdef CONFIG_64BIT
1578 	case KVM_REG_MIPS_CP0_XCONTEXT:
1579 		write_gc0_xcontext(v);
1580 		break;
1581 #endif
1582 	case KVM_REG_MIPS_CP0_ERROREPC:
1583 		write_gc0_errorepc(v);
1584 		break;
1585 	case KVM_REG_MIPS_CP0_KSCRATCH1 ... KVM_REG_MIPS_CP0_KSCRATCH6:
1586 		idx = reg->id - KVM_REG_MIPS_CP0_KSCRATCH1 + 2;
1587 		if (!cpu_guest_has_kscr(idx))
1588 			return -EINVAL;
1589 		switch (idx) {
1590 		case 2:
1591 			write_gc0_kscratch1(v);
1592 			break;
1593 		case 3:
1594 			write_gc0_kscratch2(v);
1595 			break;
1596 		case 4:
1597 			write_gc0_kscratch3(v);
1598 			break;
1599 		case 5:
1600 			write_gc0_kscratch4(v);
1601 			break;
1602 		case 6:
1603 			write_gc0_kscratch5(v);
1604 			break;
1605 		case 7:
1606 			write_gc0_kscratch6(v);
1607 			break;
1608 		}
1609 		break;
1610 	case KVM_REG_MIPS_COUNT_CTL:
1611 		ret = kvm_mips_set_count_ctl(vcpu, v);
1612 		break;
1613 	case KVM_REG_MIPS_COUNT_RESUME:
1614 		ret = kvm_mips_set_count_resume(vcpu, v);
1615 		break;
1616 	case KVM_REG_MIPS_COUNT_HZ:
1617 		ret = kvm_mips_set_count_hz(vcpu, v);
1618 		break;
1619 	default:
1620 		return -EINVAL;
1621 	}
1622 	return ret;
1623 }
1624 
1625 #define guestid_cache(cpu)	(cpu_data[cpu].guestid_cache)
1626 static void kvm_vz_get_new_guestid(unsigned long cpu, struct kvm_vcpu *vcpu)
1627 {
1628 	unsigned long guestid = guestid_cache(cpu);
1629 
1630 	if (!(++guestid & GUESTID_MASK)) {
1631 		if (cpu_has_vtag_icache)
1632 			flush_icache_all();
1633 
1634 		if (!guestid)		/* fix version if needed */
1635 			guestid = GUESTID_FIRST_VERSION;
1636 
1637 		++guestid;		/* guestid 0 reserved for root */
1638 
1639 		/* start new guestid cycle */
1640 		kvm_vz_local_flush_roottlb_all_guests();
1641 		kvm_vz_local_flush_guesttlb_all();
1642 	}
1643 
1644 	guestid_cache(cpu) = guestid;
1645 }
1646 
1647 /* Returns 1 if the guest TLB may be clobbered */
1648 static int kvm_vz_check_requests(struct kvm_vcpu *vcpu, int cpu)
1649 {
1650 	int ret = 0;
1651 	int i;
1652 
1653 	if (!vcpu->requests)
1654 		return 0;
1655 
1656 	if (kvm_check_request(KVM_REQ_TLB_FLUSH, vcpu)) {
1657 		if (cpu_has_guestid) {
1658 			/* Drop all GuestIDs for this VCPU */
1659 			for_each_possible_cpu(i)
1660 				vcpu->arch.vzguestid[i] = 0;
1661 			/* This will clobber guest TLB contents too */
1662 			ret = 1;
1663 		}
1664 		/*
1665 		 * For Root ASID Dealias (RAD) we don't do anything here, but we
1666 		 * still need the request to ensure we recheck asid_flush_mask.
1667 		 * We can still return 0 as only the root TLB will be affected
1668 		 * by a root ASID flush.
1669 		 */
1670 	}
1671 
1672 	return ret;
1673 }
1674 
1675 static void kvm_vz_vcpu_save_wired(struct kvm_vcpu *vcpu)
1676 {
1677 	unsigned int wired = read_gc0_wired();
1678 	struct kvm_mips_tlb *tlbs;
1679 	int i;
1680 
1681 	/* Expand the wired TLB array if necessary */
1682 	wired &= MIPSR6_WIRED_WIRED;
1683 	if (wired > vcpu->arch.wired_tlb_limit) {
1684 		tlbs = krealloc(vcpu->arch.wired_tlb, wired *
1685 				sizeof(*vcpu->arch.wired_tlb), GFP_ATOMIC);
1686 		if (WARN_ON(!tlbs)) {
1687 			/* Save whatever we can */
1688 			wired = vcpu->arch.wired_tlb_limit;
1689 		} else {
1690 			vcpu->arch.wired_tlb = tlbs;
1691 			vcpu->arch.wired_tlb_limit = wired;
1692 		}
1693 	}
1694 
1695 	if (wired)
1696 		/* Save wired entries from the guest TLB */
1697 		kvm_vz_save_guesttlb(vcpu->arch.wired_tlb, 0, wired);
1698 	/* Invalidate any dropped entries since last time */
1699 	for (i = wired; i < vcpu->arch.wired_tlb_used; ++i) {
1700 		vcpu->arch.wired_tlb[i].tlb_hi = UNIQUE_GUEST_ENTRYHI(i);
1701 		vcpu->arch.wired_tlb[i].tlb_lo[0] = 0;
1702 		vcpu->arch.wired_tlb[i].tlb_lo[1] = 0;
1703 		vcpu->arch.wired_tlb[i].tlb_mask = 0;
1704 	}
1705 	vcpu->arch.wired_tlb_used = wired;
1706 }
1707 
1708 static void kvm_vz_vcpu_load_wired(struct kvm_vcpu *vcpu)
1709 {
1710 	/* Load wired entries into the guest TLB */
1711 	if (vcpu->arch.wired_tlb)
1712 		kvm_vz_load_guesttlb(vcpu->arch.wired_tlb, 0,
1713 				     vcpu->arch.wired_tlb_used);
1714 }
1715 
1716 static void kvm_vz_vcpu_load_tlb(struct kvm_vcpu *vcpu, int cpu)
1717 {
1718 	struct kvm *kvm = vcpu->kvm;
1719 	struct mm_struct *gpa_mm = &kvm->arch.gpa_mm;
1720 	bool migrated;
1721 
1722 	/*
1723 	 * Are we entering guest context on a different CPU to last time?
1724 	 * If so, the VCPU's guest TLB state on this CPU may be stale.
1725 	 */
1726 	migrated = (vcpu->arch.last_exec_cpu != cpu);
1727 	vcpu->arch.last_exec_cpu = cpu;
1728 
1729 	/*
1730 	 * A vcpu's GuestID is set in GuestCtl1.ID when the vcpu is loaded and
1731 	 * remains set until another vcpu is loaded in.  As a rule GuestRID
1732 	 * remains zeroed when in root context unless the kernel is busy
1733 	 * manipulating guest tlb entries.
1734 	 */
1735 	if (cpu_has_guestid) {
1736 		/*
1737 		 * Check if our GuestID is of an older version and thus invalid.
1738 		 *
1739 		 * We also discard the stored GuestID if we've executed on
1740 		 * another CPU, as the guest mappings may have changed without
1741 		 * hypervisor knowledge.
1742 		 */
1743 		if (migrated ||
1744 		    (vcpu->arch.vzguestid[cpu] ^ guestid_cache(cpu)) &
1745 					GUESTID_VERSION_MASK) {
1746 			kvm_vz_get_new_guestid(cpu, vcpu);
1747 			vcpu->arch.vzguestid[cpu] = guestid_cache(cpu);
1748 			trace_kvm_guestid_change(vcpu,
1749 						 vcpu->arch.vzguestid[cpu]);
1750 		}
1751 
1752 		/* Restore GuestID */
1753 		change_c0_guestctl1(GUESTID_MASK, vcpu->arch.vzguestid[cpu]);
1754 	} else {
1755 		/*
1756 		 * The Guest TLB only stores a single guest's TLB state, so
1757 		 * flush it if another VCPU has executed on this CPU.
1758 		 *
1759 		 * We also flush if we've executed on another CPU, as the guest
1760 		 * mappings may have changed without hypervisor knowledge.
1761 		 */
1762 		if (migrated || last_exec_vcpu[cpu] != vcpu)
1763 			kvm_vz_local_flush_guesttlb_all();
1764 		last_exec_vcpu[cpu] = vcpu;
1765 
1766 		/*
1767 		 * Root ASID dealiases guest GPA mappings in the root TLB.
1768 		 * Allocate new root ASID if needed.
1769 		 */
1770 		if (cpumask_test_and_clear_cpu(cpu, &kvm->arch.asid_flush_mask)
1771 		    || (cpu_context(cpu, gpa_mm) ^ asid_cache(cpu)) &
1772 						asid_version_mask(cpu))
1773 			get_new_mmu_context(gpa_mm, cpu);
1774 	}
1775 }
1776 
1777 static int kvm_vz_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
1778 {
1779 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1780 	bool migrated, all;
1781 
1782 	/*
1783 	 * Have we migrated to a different CPU?
1784 	 * If so, any old guest TLB state may be stale.
1785 	 */
1786 	migrated = (vcpu->arch.last_sched_cpu != cpu);
1787 
1788 	/*
1789 	 * Was this the last VCPU to run on this CPU?
1790 	 * If not, any old guest state from this VCPU will have been clobbered.
1791 	 */
1792 	all = migrated || (last_vcpu[cpu] != vcpu);
1793 	last_vcpu[cpu] = vcpu;
1794 
1795 	/*
1796 	 * Restore CP0_Wired unconditionally as we clear it after use, and
1797 	 * restore wired guest TLB entries (while in guest context).
1798 	 */
1799 	kvm_restore_gc0_wired(cop0);
1800 	if (current->flags & PF_VCPU) {
1801 		tlbw_use_hazard();
1802 		kvm_vz_vcpu_load_tlb(vcpu, cpu);
1803 		kvm_vz_vcpu_load_wired(vcpu);
1804 	}
1805 
1806 	/*
1807 	 * Restore timer state regardless, as e.g. Cause.TI can change over time
1808 	 * if left unmaintained.
1809 	 */
1810 	kvm_vz_restore_timer(vcpu);
1811 
1812 	/* Don't bother restoring registers multiple times unless necessary */
1813 	if (!all)
1814 		return 0;
1815 
1816 	/*
1817 	 * Restore config registers first, as some implementations restrict
1818 	 * writes to other registers when the corresponding feature bits aren't
1819 	 * set. For example Status.CU1 cannot be set unless Config1.FP is set.
1820 	 */
1821 	kvm_restore_gc0_config(cop0);
1822 	if (cpu_guest_has_conf1)
1823 		kvm_restore_gc0_config1(cop0);
1824 	if (cpu_guest_has_conf2)
1825 		kvm_restore_gc0_config2(cop0);
1826 	if (cpu_guest_has_conf3)
1827 		kvm_restore_gc0_config3(cop0);
1828 	if (cpu_guest_has_conf4)
1829 		kvm_restore_gc0_config4(cop0);
1830 	if (cpu_guest_has_conf5)
1831 		kvm_restore_gc0_config5(cop0);
1832 	if (cpu_guest_has_conf6)
1833 		kvm_restore_gc0_config6(cop0);
1834 	if (cpu_guest_has_conf7)
1835 		kvm_restore_gc0_config7(cop0);
1836 
1837 	kvm_restore_gc0_index(cop0);
1838 	kvm_restore_gc0_entrylo0(cop0);
1839 	kvm_restore_gc0_entrylo1(cop0);
1840 	kvm_restore_gc0_context(cop0);
1841 #ifdef CONFIG_64BIT
1842 	kvm_restore_gc0_xcontext(cop0);
1843 #endif
1844 	kvm_restore_gc0_pagemask(cop0);
1845 	kvm_restore_gc0_pagegrain(cop0);
1846 	kvm_restore_gc0_hwrena(cop0);
1847 	kvm_restore_gc0_badvaddr(cop0);
1848 	kvm_restore_gc0_entryhi(cop0);
1849 	kvm_restore_gc0_status(cop0);
1850 	kvm_restore_gc0_intctl(cop0);
1851 	kvm_restore_gc0_epc(cop0);
1852 	kvm_vz_write_gc0_ebase(kvm_read_sw_gc0_ebase(cop0));
1853 	if (cpu_guest_has_userlocal)
1854 		kvm_restore_gc0_userlocal(cop0);
1855 
1856 	kvm_restore_gc0_errorepc(cop0);
1857 
1858 	/* restore KScratch registers if enabled in guest */
1859 	if (cpu_guest_has_conf4) {
1860 		if (cpu_guest_has_kscr(2))
1861 			kvm_restore_gc0_kscratch1(cop0);
1862 		if (cpu_guest_has_kscr(3))
1863 			kvm_restore_gc0_kscratch2(cop0);
1864 		if (cpu_guest_has_kscr(4))
1865 			kvm_restore_gc0_kscratch3(cop0);
1866 		if (cpu_guest_has_kscr(5))
1867 			kvm_restore_gc0_kscratch4(cop0);
1868 		if (cpu_guest_has_kscr(6))
1869 			kvm_restore_gc0_kscratch5(cop0);
1870 		if (cpu_guest_has_kscr(7))
1871 			kvm_restore_gc0_kscratch6(cop0);
1872 	}
1873 
1874 	/* restore Root.GuestCtl2 from unused Guest guestctl2 register */
1875 	if (cpu_has_guestctl2)
1876 		write_c0_guestctl2(
1877 			cop0->reg[MIPS_CP0_GUESTCTL2][MIPS_CP0_GUESTCTL2_SEL]);
1878 
1879 	return 0;
1880 }
1881 
1882 static int kvm_vz_vcpu_put(struct kvm_vcpu *vcpu, int cpu)
1883 {
1884 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1885 
1886 	if (current->flags & PF_VCPU)
1887 		kvm_vz_vcpu_save_wired(vcpu);
1888 
1889 	kvm_lose_fpu(vcpu);
1890 
1891 	kvm_save_gc0_index(cop0);
1892 	kvm_save_gc0_entrylo0(cop0);
1893 	kvm_save_gc0_entrylo1(cop0);
1894 	kvm_save_gc0_context(cop0);
1895 #ifdef CONFIG_64BIT
1896 	kvm_save_gc0_xcontext(cop0);
1897 #endif
1898 	kvm_save_gc0_pagemask(cop0);
1899 	kvm_save_gc0_pagegrain(cop0);
1900 	kvm_save_gc0_wired(cop0);
1901 	/* allow wired TLB entries to be overwritten */
1902 	clear_gc0_wired(MIPSR6_WIRED_WIRED);
1903 	kvm_save_gc0_hwrena(cop0);
1904 	kvm_save_gc0_badvaddr(cop0);
1905 	kvm_save_gc0_entryhi(cop0);
1906 	kvm_save_gc0_status(cop0);
1907 	kvm_save_gc0_intctl(cop0);
1908 	kvm_save_gc0_epc(cop0);
1909 	kvm_write_sw_gc0_ebase(cop0, kvm_vz_read_gc0_ebase());
1910 	if (cpu_guest_has_userlocal)
1911 		kvm_save_gc0_userlocal(cop0);
1912 
1913 	/* only save implemented config registers */
1914 	kvm_save_gc0_config(cop0);
1915 	if (cpu_guest_has_conf1)
1916 		kvm_save_gc0_config1(cop0);
1917 	if (cpu_guest_has_conf2)
1918 		kvm_save_gc0_config2(cop0);
1919 	if (cpu_guest_has_conf3)
1920 		kvm_save_gc0_config3(cop0);
1921 	if (cpu_guest_has_conf4)
1922 		kvm_save_gc0_config4(cop0);
1923 	if (cpu_guest_has_conf5)
1924 		kvm_save_gc0_config5(cop0);
1925 	if (cpu_guest_has_conf6)
1926 		kvm_save_gc0_config6(cop0);
1927 	if (cpu_guest_has_conf7)
1928 		kvm_save_gc0_config7(cop0);
1929 
1930 	kvm_save_gc0_errorepc(cop0);
1931 
1932 	/* save KScratch registers if enabled in guest */
1933 	if (cpu_guest_has_conf4) {
1934 		if (cpu_guest_has_kscr(2))
1935 			kvm_save_gc0_kscratch1(cop0);
1936 		if (cpu_guest_has_kscr(3))
1937 			kvm_save_gc0_kscratch2(cop0);
1938 		if (cpu_guest_has_kscr(4))
1939 			kvm_save_gc0_kscratch3(cop0);
1940 		if (cpu_guest_has_kscr(5))
1941 			kvm_save_gc0_kscratch4(cop0);
1942 		if (cpu_guest_has_kscr(6))
1943 			kvm_save_gc0_kscratch5(cop0);
1944 		if (cpu_guest_has_kscr(7))
1945 			kvm_save_gc0_kscratch6(cop0);
1946 	}
1947 
1948 	kvm_vz_save_timer(vcpu);
1949 
1950 	/* save Root.GuestCtl2 in unused Guest guestctl2 register */
1951 	if (cpu_has_guestctl2)
1952 		cop0->reg[MIPS_CP0_GUESTCTL2][MIPS_CP0_GUESTCTL2_SEL] =
1953 			read_c0_guestctl2();
1954 
1955 	return 0;
1956 }
1957 
1958 /**
1959  * kvm_vz_resize_guest_vtlb() - Attempt to resize guest VTLB.
1960  * @size:	Number of guest VTLB entries (0 < @size <= root VTLB entries).
1961  *
1962  * Attempt to resize the guest VTLB by writing guest Config registers. This is
1963  * necessary for cores with a shared root/guest TLB to avoid overlap with wired
1964  * entries in the root VTLB.
1965  *
1966  * Returns:	The resulting guest VTLB size.
1967  */
1968 static unsigned int kvm_vz_resize_guest_vtlb(unsigned int size)
1969 {
1970 	unsigned int config4 = 0, ret = 0, limit;
1971 
1972 	/* Write MMUSize - 1 into guest Config registers */
1973 	if (cpu_guest_has_conf1)
1974 		change_gc0_config1(MIPS_CONF1_TLBS,
1975 				   (size - 1) << MIPS_CONF1_TLBS_SHIFT);
1976 	if (cpu_guest_has_conf4) {
1977 		config4 = read_gc0_config4();
1978 		if (cpu_has_mips_r6 || (config4 & MIPS_CONF4_MMUEXTDEF) ==
1979 		    MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT) {
1980 			config4 &= ~MIPS_CONF4_VTLBSIZEEXT;
1981 			config4 |= ((size - 1) >> MIPS_CONF1_TLBS_SIZE) <<
1982 				MIPS_CONF4_VTLBSIZEEXT_SHIFT;
1983 		} else if ((config4 & MIPS_CONF4_MMUEXTDEF) ==
1984 			   MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT) {
1985 			config4 &= ~MIPS_CONF4_MMUSIZEEXT;
1986 			config4 |= ((size - 1) >> MIPS_CONF1_TLBS_SIZE) <<
1987 				MIPS_CONF4_MMUSIZEEXT_SHIFT;
1988 		}
1989 		write_gc0_config4(config4);
1990 	}
1991 
1992 	/*
1993 	 * Set Guest.Wired.Limit = 0 (no limit up to Guest.MMUSize-1), unless it
1994 	 * would exceed Root.Wired.Limit (clearing Guest.Wired.Wired so write
1995 	 * not dropped)
1996 	 */
1997 	if (cpu_has_mips_r6) {
1998 		limit = (read_c0_wired() & MIPSR6_WIRED_LIMIT) >>
1999 						MIPSR6_WIRED_LIMIT_SHIFT;
2000 		if (size - 1 <= limit)
2001 			limit = 0;
2002 		write_gc0_wired(limit << MIPSR6_WIRED_LIMIT_SHIFT);
2003 	}
2004 
2005 	/* Read back MMUSize - 1 */
2006 	back_to_back_c0_hazard();
2007 	if (cpu_guest_has_conf1)
2008 		ret = (read_gc0_config1() & MIPS_CONF1_TLBS) >>
2009 						MIPS_CONF1_TLBS_SHIFT;
2010 	if (config4) {
2011 		if (cpu_has_mips_r6 || (config4 & MIPS_CONF4_MMUEXTDEF) ==
2012 		    MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT)
2013 			ret |= ((config4 & MIPS_CONF4_VTLBSIZEEXT) >>
2014 				MIPS_CONF4_VTLBSIZEEXT_SHIFT) <<
2015 				MIPS_CONF1_TLBS_SIZE;
2016 		else if ((config4 & MIPS_CONF4_MMUEXTDEF) ==
2017 			 MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT)
2018 			ret |= ((config4 & MIPS_CONF4_MMUSIZEEXT) >>
2019 				MIPS_CONF4_MMUSIZEEXT_SHIFT) <<
2020 				MIPS_CONF1_TLBS_SIZE;
2021 	}
2022 	return ret + 1;
2023 }
2024 
2025 static int kvm_vz_hardware_enable(void)
2026 {
2027 	unsigned int mmu_size, guest_mmu_size, ftlb_size;
2028 
2029 	/*
2030 	 * ImgTec cores tend to use a shared root/guest TLB. To avoid overlap of
2031 	 * root wired and guest entries, the guest TLB may need resizing.
2032 	 */
2033 	mmu_size = current_cpu_data.tlbsizevtlb;
2034 	ftlb_size = current_cpu_data.tlbsize - mmu_size;
2035 
2036 	/* Try switching to maximum guest VTLB size for flush */
2037 	guest_mmu_size = kvm_vz_resize_guest_vtlb(mmu_size);
2038 	current_cpu_data.guest.tlbsize = guest_mmu_size + ftlb_size;
2039 	kvm_vz_local_flush_guesttlb_all();
2040 
2041 	/*
2042 	 * Reduce to make space for root wired entries and at least 2 root
2043 	 * non-wired entries. This does assume that long-term wired entries
2044 	 * won't be added later.
2045 	 */
2046 	guest_mmu_size = mmu_size - num_wired_entries() - 2;
2047 	guest_mmu_size = kvm_vz_resize_guest_vtlb(guest_mmu_size);
2048 	current_cpu_data.guest.tlbsize = guest_mmu_size + ftlb_size;
2049 
2050 	/*
2051 	 * Write the VTLB size, but if another CPU has already written, check it
2052 	 * matches or we won't provide a consistent view to the guest. If this
2053 	 * ever happens it suggests an asymmetric number of wired entries.
2054 	 */
2055 	if (cmpxchg(&kvm_vz_guest_vtlb_size, 0, guest_mmu_size) &&
2056 	    WARN(guest_mmu_size != kvm_vz_guest_vtlb_size,
2057 		 "Available guest VTLB size mismatch"))
2058 		return -EINVAL;
2059 
2060 	/*
2061 	 * Enable virtualization features granting guest direct control of
2062 	 * certain features:
2063 	 * CP0=1:	Guest coprocessor 0 context.
2064 	 * AT=Guest:	Guest MMU.
2065 	 * CG=1:	Hit (virtual address) CACHE operations (optional).
2066 	 * CF=1:	Guest Config registers.
2067 	 * CGI=1:	Indexed flush CACHE operations (optional).
2068 	 */
2069 	write_c0_guestctl0(MIPS_GCTL0_CP0 |
2070 			   (MIPS_GCTL0_AT_GUEST << MIPS_GCTL0_AT_SHIFT) |
2071 			   MIPS_GCTL0_CG | MIPS_GCTL0_CF);
2072 	if (cpu_has_guestctl0ext)
2073 		set_c0_guestctl0ext(MIPS_GCTL0EXT_CGI);
2074 
2075 	if (cpu_has_guestid) {
2076 		write_c0_guestctl1(0);
2077 		kvm_vz_local_flush_roottlb_all_guests();
2078 
2079 		GUESTID_MASK = current_cpu_data.guestid_mask;
2080 		GUESTID_FIRST_VERSION = GUESTID_MASK + 1;
2081 		GUESTID_VERSION_MASK = ~GUESTID_MASK;
2082 
2083 		current_cpu_data.guestid_cache = GUESTID_FIRST_VERSION;
2084 	}
2085 
2086 	/* clear any pending injected virtual guest interrupts */
2087 	if (cpu_has_guestctl2)
2088 		clear_c0_guestctl2(0x3f << 10);
2089 
2090 	return 0;
2091 }
2092 
2093 static void kvm_vz_hardware_disable(void)
2094 {
2095 	kvm_vz_local_flush_guesttlb_all();
2096 
2097 	if (cpu_has_guestid) {
2098 		write_c0_guestctl1(0);
2099 		kvm_vz_local_flush_roottlb_all_guests();
2100 	}
2101 }
2102 
2103 static int kvm_vz_check_extension(struct kvm *kvm, long ext)
2104 {
2105 	int r;
2106 
2107 	switch (ext) {
2108 	case KVM_CAP_MIPS_VZ:
2109 		/* we wouldn't be here unless cpu_has_vz */
2110 		r = 1;
2111 		break;
2112 #ifdef CONFIG_64BIT
2113 	case KVM_CAP_MIPS_64BIT:
2114 		/* We support 64-bit registers/operations and addresses */
2115 		r = 2;
2116 		break;
2117 #endif
2118 	default:
2119 		r = 0;
2120 		break;
2121 	}
2122 
2123 	return r;
2124 }
2125 
2126 static int kvm_vz_vcpu_init(struct kvm_vcpu *vcpu)
2127 {
2128 	int i;
2129 
2130 	for_each_possible_cpu(i)
2131 		vcpu->arch.vzguestid[i] = 0;
2132 
2133 	return 0;
2134 }
2135 
2136 static void kvm_vz_vcpu_uninit(struct kvm_vcpu *vcpu)
2137 {
2138 	int cpu;
2139 
2140 	/*
2141 	 * If the VCPU is freed and reused as another VCPU, we don't want the
2142 	 * matching pointer wrongly hanging around in last_vcpu[] or
2143 	 * last_exec_vcpu[].
2144 	 */
2145 	for_each_possible_cpu(cpu) {
2146 		if (last_vcpu[cpu] == vcpu)
2147 			last_vcpu[cpu] = NULL;
2148 		if (last_exec_vcpu[cpu] == vcpu)
2149 			last_exec_vcpu[cpu] = NULL;
2150 	}
2151 }
2152 
2153 static int kvm_vz_vcpu_setup(struct kvm_vcpu *vcpu)
2154 {
2155 	struct mips_coproc *cop0 = vcpu->arch.cop0;
2156 	unsigned long count_hz = 100*1000*1000; /* default to 100 MHz */
2157 
2158 	/*
2159 	 * Start off the timer at the same frequency as the host timer, but the
2160 	 * soft timer doesn't handle frequencies greater than 1GHz yet.
2161 	 */
2162 	if (mips_hpt_frequency && mips_hpt_frequency <= NSEC_PER_SEC)
2163 		count_hz = mips_hpt_frequency;
2164 	kvm_mips_init_count(vcpu, count_hz);
2165 
2166 	/*
2167 	 * Initialize guest register state to valid architectural reset state.
2168 	 */
2169 
2170 	/* PageGrain */
2171 	if (cpu_has_mips_r6)
2172 		kvm_write_sw_gc0_pagegrain(cop0, PG_RIE | PG_XIE | PG_IEC);
2173 	/* Wired */
2174 	if (cpu_has_mips_r6)
2175 		kvm_write_sw_gc0_wired(cop0,
2176 				       read_gc0_wired() & MIPSR6_WIRED_LIMIT);
2177 	/* Status */
2178 	kvm_write_sw_gc0_status(cop0, ST0_BEV | ST0_ERL);
2179 	if (cpu_has_mips_r6)
2180 		kvm_change_sw_gc0_status(cop0, ST0_FR, read_gc0_status());
2181 	/* IntCtl */
2182 	kvm_write_sw_gc0_intctl(cop0, read_gc0_intctl() &
2183 				(INTCTLF_IPFDC | INTCTLF_IPPCI | INTCTLF_IPTI));
2184 	/* PRId */
2185 	kvm_write_sw_gc0_prid(cop0, boot_cpu_data.processor_id);
2186 	/* EBase */
2187 	kvm_write_sw_gc0_ebase(cop0, (s32)0x80000000 | vcpu->vcpu_id);
2188 	/* Config */
2189 	kvm_save_gc0_config(cop0);
2190 	/* architecturally writable (e.g. from guest) */
2191 	kvm_change_sw_gc0_config(cop0, CONF_CM_CMASK,
2192 				 _page_cachable_default >> _CACHE_SHIFT);
2193 	/* architecturally read only, but maybe writable from root */
2194 	kvm_change_sw_gc0_config(cop0, MIPS_CONF_MT, read_c0_config());
2195 	if (cpu_guest_has_conf1) {
2196 		kvm_set_sw_gc0_config(cop0, MIPS_CONF_M);
2197 		/* Config1 */
2198 		kvm_save_gc0_config1(cop0);
2199 		/* architecturally read only, but maybe writable from root */
2200 		kvm_clear_sw_gc0_config1(cop0, MIPS_CONF1_C2	|
2201 					       MIPS_CONF1_MD	|
2202 					       MIPS_CONF1_PC	|
2203 					       MIPS_CONF1_WR	|
2204 					       MIPS_CONF1_CA	|
2205 					       MIPS_CONF1_FP);
2206 	}
2207 	if (cpu_guest_has_conf2) {
2208 		kvm_set_sw_gc0_config1(cop0, MIPS_CONF_M);
2209 		/* Config2 */
2210 		kvm_save_gc0_config2(cop0);
2211 	}
2212 	if (cpu_guest_has_conf3) {
2213 		kvm_set_sw_gc0_config2(cop0, MIPS_CONF_M);
2214 		/* Config3 */
2215 		kvm_save_gc0_config3(cop0);
2216 		/* architecturally writable (e.g. from guest) */
2217 		kvm_clear_sw_gc0_config3(cop0, MIPS_CONF3_ISA_OE);
2218 		/* architecturally read only, but maybe writable from root */
2219 		kvm_clear_sw_gc0_config3(cop0, MIPS_CONF3_MSA	|
2220 					       MIPS_CONF3_BPG	|
2221 					       MIPS_CONF3_ULRI	|
2222 					       MIPS_CONF3_DSP	|
2223 					       MIPS_CONF3_CTXTC	|
2224 					       MIPS_CONF3_ITL	|
2225 					       MIPS_CONF3_LPA	|
2226 					       MIPS_CONF3_VEIC	|
2227 					       MIPS_CONF3_VINT	|
2228 					       MIPS_CONF3_SP	|
2229 					       MIPS_CONF3_CDMM	|
2230 					       MIPS_CONF3_MT	|
2231 					       MIPS_CONF3_SM	|
2232 					       MIPS_CONF3_TL);
2233 	}
2234 	if (cpu_guest_has_conf4) {
2235 		kvm_set_sw_gc0_config3(cop0, MIPS_CONF_M);
2236 		/* Config4 */
2237 		kvm_save_gc0_config4(cop0);
2238 	}
2239 	if (cpu_guest_has_conf5) {
2240 		kvm_set_sw_gc0_config4(cop0, MIPS_CONF_M);
2241 		/* Config5 */
2242 		kvm_save_gc0_config5(cop0);
2243 		/* architecturally writable (e.g. from guest) */
2244 		kvm_clear_sw_gc0_config5(cop0, MIPS_CONF5_K	|
2245 					       MIPS_CONF5_CV	|
2246 					       MIPS_CONF5_MSAEN	|
2247 					       MIPS_CONF5_UFE	|
2248 					       MIPS_CONF5_FRE	|
2249 					       MIPS_CONF5_SBRI	|
2250 					       MIPS_CONF5_UFR);
2251 		/* architecturally read only, but maybe writable from root */
2252 		kvm_clear_sw_gc0_config5(cop0, MIPS_CONF5_MRP);
2253 	}
2254 
2255 	/* start with no pending virtual guest interrupts */
2256 	if (cpu_has_guestctl2)
2257 		cop0->reg[MIPS_CP0_GUESTCTL2][MIPS_CP0_GUESTCTL2_SEL] = 0;
2258 
2259 	/* Put PC at reset vector */
2260 	vcpu->arch.pc = CKSEG1ADDR(0x1fc00000);
2261 
2262 	return 0;
2263 }
2264 
2265 static void kvm_vz_flush_shadow_all(struct kvm *kvm)
2266 {
2267 	if (cpu_has_guestid) {
2268 		/* Flush GuestID for each VCPU individually */
2269 		kvm_flush_remote_tlbs(kvm);
2270 	} else {
2271 		/*
2272 		 * For each CPU there is a single GPA ASID used by all VCPUs in
2273 		 * the VM, so it doesn't make sense for the VCPUs to handle
2274 		 * invalidation of these ASIDs individually.
2275 		 *
2276 		 * Instead mark all CPUs as needing ASID invalidation in
2277 		 * asid_flush_mask, and just use kvm_flush_remote_tlbs(kvm) to
2278 		 * kick any running VCPUs so they check asid_flush_mask.
2279 		 */
2280 		cpumask_setall(&kvm->arch.asid_flush_mask);
2281 		kvm_flush_remote_tlbs(kvm);
2282 	}
2283 }
2284 
2285 static void kvm_vz_flush_shadow_memslot(struct kvm *kvm,
2286 					const struct kvm_memory_slot *slot)
2287 {
2288 	kvm_vz_flush_shadow_all(kvm);
2289 }
2290 
2291 static void kvm_vz_vcpu_reenter(struct kvm_run *run, struct kvm_vcpu *vcpu)
2292 {
2293 	int cpu = smp_processor_id();
2294 	int preserve_guest_tlb;
2295 
2296 	preserve_guest_tlb = kvm_vz_check_requests(vcpu, cpu);
2297 
2298 	if (preserve_guest_tlb)
2299 		kvm_vz_vcpu_save_wired(vcpu);
2300 
2301 	kvm_vz_vcpu_load_tlb(vcpu, cpu);
2302 
2303 	if (preserve_guest_tlb)
2304 		kvm_vz_vcpu_load_wired(vcpu);
2305 }
2306 
2307 static int kvm_vz_vcpu_run(struct kvm_run *run, struct kvm_vcpu *vcpu)
2308 {
2309 	int cpu = smp_processor_id();
2310 	int r;
2311 
2312 	/* Check if we have any exceptions/interrupts pending */
2313 	kvm_mips_deliver_interrupts(vcpu, read_gc0_cause());
2314 
2315 	kvm_vz_check_requests(vcpu, cpu);
2316 	kvm_vz_vcpu_load_tlb(vcpu, cpu);
2317 	kvm_vz_vcpu_load_wired(vcpu);
2318 
2319 	r = vcpu->arch.vcpu_run(run, vcpu);
2320 
2321 	kvm_vz_vcpu_save_wired(vcpu);
2322 
2323 	return r;
2324 }
2325 
2326 static struct kvm_mips_callbacks kvm_vz_callbacks = {
2327 	.handle_cop_unusable = kvm_trap_vz_handle_cop_unusable,
2328 	.handle_tlb_mod = kvm_trap_vz_handle_tlb_st_miss,
2329 	.handle_tlb_ld_miss = kvm_trap_vz_handle_tlb_ld_miss,
2330 	.handle_tlb_st_miss = kvm_trap_vz_handle_tlb_st_miss,
2331 	.handle_addr_err_st = kvm_trap_vz_no_handler,
2332 	.handle_addr_err_ld = kvm_trap_vz_no_handler,
2333 	.handle_syscall = kvm_trap_vz_no_handler,
2334 	.handle_res_inst = kvm_trap_vz_no_handler,
2335 	.handle_break = kvm_trap_vz_no_handler,
2336 	.handle_msa_disabled = kvm_trap_vz_handle_msa_disabled,
2337 	.handle_guest_exit = kvm_trap_vz_handle_guest_exit,
2338 
2339 	.hardware_enable = kvm_vz_hardware_enable,
2340 	.hardware_disable = kvm_vz_hardware_disable,
2341 	.check_extension = kvm_vz_check_extension,
2342 	.vcpu_init = kvm_vz_vcpu_init,
2343 	.vcpu_uninit = kvm_vz_vcpu_uninit,
2344 	.vcpu_setup = kvm_vz_vcpu_setup,
2345 	.flush_shadow_all = kvm_vz_flush_shadow_all,
2346 	.flush_shadow_memslot = kvm_vz_flush_shadow_memslot,
2347 	.gva_to_gpa = kvm_vz_gva_to_gpa_cb,
2348 	.queue_timer_int = kvm_vz_queue_timer_int_cb,
2349 	.dequeue_timer_int = kvm_vz_dequeue_timer_int_cb,
2350 	.queue_io_int = kvm_vz_queue_io_int_cb,
2351 	.dequeue_io_int = kvm_vz_dequeue_io_int_cb,
2352 	.irq_deliver = kvm_vz_irq_deliver_cb,
2353 	.irq_clear = kvm_vz_irq_clear_cb,
2354 	.num_regs = kvm_vz_num_regs,
2355 	.copy_reg_indices = kvm_vz_copy_reg_indices,
2356 	.get_one_reg = kvm_vz_get_one_reg,
2357 	.set_one_reg = kvm_vz_set_one_reg,
2358 	.vcpu_load = kvm_vz_vcpu_load,
2359 	.vcpu_put = kvm_vz_vcpu_put,
2360 	.vcpu_run = kvm_vz_vcpu_run,
2361 	.vcpu_reenter = kvm_vz_vcpu_reenter,
2362 };
2363 
2364 int kvm_mips_emulation_init(struct kvm_mips_callbacks **install_callbacks)
2365 {
2366 	if (!cpu_has_vz)
2367 		return -ENODEV;
2368 
2369 	/*
2370 	 * VZ requires at least 2 KScratch registers, so it should have been
2371 	 * possible to allocate pgd_reg.
2372 	 */
2373 	if (WARN(pgd_reg == -1,
2374 		 "pgd_reg not allocated even though cpu_has_vz\n"))
2375 		return -ENODEV;
2376 
2377 	pr_info("Starting KVM with MIPS VZ extensions\n");
2378 
2379 	*install_callbacks = &kvm_vz_callbacks;
2380 	return 0;
2381 }
2382