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: Deliver/Emulate exceptions to the guest kernel
7 *
8 * Copyright (C) 2012  MIPS Technologies, Inc.  All rights reserved.
9 * Authors: Sanjay Lal <sanjayl@kymasys.com>
10 */
11
12#include <linux/errno.h>
13#include <linux/err.h>
14#include <linux/kvm_host.h>
15#include <linux/log2.h>
16#include <linux/uaccess.h>
17#include <linux/vmalloc.h>
18#include <asm/mmu_context.h>
19#include <asm/pgalloc.h>
20
21#include "interrupt.h"
22
23static gpa_t kvm_trap_emul_gva_to_gpa_cb(gva_t gva)
24{
25	gpa_t gpa;
26	gva_t kseg = KSEGX(gva);
27	gva_t gkseg = KVM_GUEST_KSEGX(gva);
28
29	if ((kseg == CKSEG0) || (kseg == CKSEG1))
30		gpa = CPHYSADDR(gva);
31	else if (gkseg == KVM_GUEST_KSEG0)
32		gpa = KVM_GUEST_CPHYSADDR(gva);
33	else {
34		kvm_err("%s: cannot find GPA for GVA: %#lx\n", __func__, gva);
35		kvm_mips_dump_host_tlbs();
36		gpa = KVM_INVALID_ADDR;
37	}
38
39	kvm_debug("%s: gva %#lx, gpa: %#llx\n", __func__, gva, gpa);
40
41	return gpa;
42}
43
44static int kvm_trap_emul_no_handler(struct kvm_vcpu *vcpu)
45{
46	u32 __user *opc = (u32 __user *) vcpu->arch.pc;
47	u32 cause = vcpu->arch.host_cp0_cause;
48	u32 exccode = (cause & CAUSEF_EXCCODE) >> CAUSEB_EXCCODE;
49	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
50	u32 inst = 0;
51
52	/*
53	 *  Fetch the instruction.
54	 */
55	if (cause & CAUSEF_BD)
56		opc += 1;
57	kvm_get_badinstr(opc, vcpu, &inst);
58
59	kvm_err("Exception Code: %d not handled @ PC: %p, inst: 0x%08x BadVaddr: %#lx Status: %#x\n",
60		exccode, opc, inst, badvaddr,
61		kvm_read_c0_guest_status(vcpu->arch.cop0));
62	kvm_arch_vcpu_dump_regs(vcpu);
63	vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
64	return RESUME_HOST;
65}
66
67static int kvm_trap_emul_handle_cop_unusable(struct kvm_vcpu *vcpu)
68{
69	struct mips_coproc *cop0 = vcpu->arch.cop0;
70	u32 __user *opc = (u32 __user *) vcpu->arch.pc;
71	u32 cause = vcpu->arch.host_cp0_cause;
72	enum emulation_result er = EMULATE_DONE;
73	int ret = RESUME_GUEST;
74
75	if (((cause & CAUSEF_CE) >> CAUSEB_CE) == 1) {
76		/* FPU Unusable */
77		if (!kvm_mips_guest_has_fpu(&vcpu->arch) ||
78		    (kvm_read_c0_guest_status(cop0) & ST0_CU1) == 0) {
79			/*
80			 * Unusable/no FPU in guest:
81			 * deliver guest COP1 Unusable Exception
82			 */
83			er = kvm_mips_emulate_fpu_exc(cause, opc, vcpu);
84		} else {
85			/* Restore FPU state */
86			kvm_own_fpu(vcpu);
87			er = EMULATE_DONE;
88		}
89	} else {
90		er = kvm_mips_emulate_inst(cause, opc, vcpu);
91	}
92
93	switch (er) {
94	case EMULATE_DONE:
95		ret = RESUME_GUEST;
96		break;
97
98	case EMULATE_FAIL:
99		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
100		ret = RESUME_HOST;
101		break;
102
103	case EMULATE_WAIT:
104		vcpu->run->exit_reason = KVM_EXIT_INTR;
105		ret = RESUME_HOST;
106		break;
107
108	case EMULATE_HYPERCALL:
109		ret = kvm_mips_handle_hypcall(vcpu);
110		break;
111
112	default:
113		BUG();
114	}
115	return ret;
116}
117
118static int kvm_mips_bad_load(u32 cause, u32 *opc, struct kvm_vcpu *vcpu)
119{
120	enum emulation_result er;
121	union mips_instruction inst;
122	int err;
123
124	/* A code fetch fault doesn't count as an MMIO */
125	if (kvm_is_ifetch_fault(&vcpu->arch)) {
126		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
127		return RESUME_HOST;
128	}
129
130	/* Fetch the instruction. */
131	if (cause & CAUSEF_BD)
132		opc += 1;
133	err = kvm_get_badinstr(opc, vcpu, &inst.word);
134	if (err) {
135		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
136		return RESUME_HOST;
137	}
138
139	/* Emulate the load */
140	er = kvm_mips_emulate_load(inst, cause, vcpu);
141	if (er == EMULATE_FAIL) {
142		kvm_err("Emulate load from MMIO space failed\n");
143		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
144	} else {
145		vcpu->run->exit_reason = KVM_EXIT_MMIO;
146	}
147	return RESUME_HOST;
148}
149
150static int kvm_mips_bad_store(u32 cause, u32 *opc, struct kvm_vcpu *vcpu)
151{
152	enum emulation_result er;
153	union mips_instruction inst;
154	int err;
155
156	/* Fetch the instruction. */
157	if (cause & CAUSEF_BD)
158		opc += 1;
159	err = kvm_get_badinstr(opc, vcpu, &inst.word);
160	if (err) {
161		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
162		return RESUME_HOST;
163	}
164
165	/* Emulate the store */
166	er = kvm_mips_emulate_store(inst, cause, vcpu);
167	if (er == EMULATE_FAIL) {
168		kvm_err("Emulate store to MMIO space failed\n");
169		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
170	} else {
171		vcpu->run->exit_reason = KVM_EXIT_MMIO;
172	}
173	return RESUME_HOST;
174}
175
176static int kvm_mips_bad_access(u32 cause, u32 *opc,
177			       struct kvm_vcpu *vcpu, bool store)
178{
179	if (store)
180		return kvm_mips_bad_store(cause, opc, vcpu);
181	else
182		return kvm_mips_bad_load(cause, opc, vcpu);
183}
184
185static int kvm_trap_emul_handle_tlb_mod(struct kvm_vcpu *vcpu)
186{
187	struct mips_coproc *cop0 = vcpu->arch.cop0;
188	u32 __user *opc = (u32 __user *) vcpu->arch.pc;
189	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
190	u32 cause = vcpu->arch.host_cp0_cause;
191	struct kvm_mips_tlb *tlb;
192	unsigned long entryhi;
193	int index;
194
195	if (KVM_GUEST_KSEGX(badvaddr) < KVM_GUEST_KSEG0
196	    || KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG23) {
197		/*
198		 * First find the mapping in the guest TLB. If the failure to
199		 * write was due to the guest TLB, it should be up to the guest
200		 * to handle it.
201		 */
202		entryhi = (badvaddr & VPN2_MASK) |
203			  (kvm_read_c0_guest_entryhi(cop0) & KVM_ENTRYHI_ASID);
204		index = kvm_mips_guest_tlb_lookup(vcpu, entryhi);
205
206		/*
207		 * These should never happen.
208		 * They would indicate stale host TLB entries.
209		 */
210		if (unlikely(index < 0)) {
211			vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
212			return RESUME_HOST;
213		}
214		tlb = vcpu->arch.guest_tlb + index;
215		if (unlikely(!TLB_IS_VALID(*tlb, badvaddr))) {
216			vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
217			return RESUME_HOST;
218		}
219
220		/*
221		 * Guest entry not dirty? That would explain the TLB modified
222		 * exception. Relay that on to the guest so it can handle it.
223		 */
224		if (!TLB_IS_DIRTY(*tlb, badvaddr)) {
225			kvm_mips_emulate_tlbmod(cause, opc, vcpu);
226			return RESUME_GUEST;
227		}
228
229		if (kvm_mips_handle_mapped_seg_tlb_fault(vcpu, tlb, badvaddr,
230							 true))
231			/* Not writable, needs handling as MMIO */
232			return kvm_mips_bad_store(cause, opc, vcpu);
233		return RESUME_GUEST;
234	} else if (KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG0) {
235		if (kvm_mips_handle_kseg0_tlb_fault(badvaddr, vcpu, true) < 0)
236			/* Not writable, needs handling as MMIO */
237			return kvm_mips_bad_store(cause, opc, vcpu);
238		return RESUME_GUEST;
239	} else {
240		/* host kernel addresses are all handled as MMIO */
241		return kvm_mips_bad_store(cause, opc, vcpu);
242	}
243}
244
245static int kvm_trap_emul_handle_tlb_miss(struct kvm_vcpu *vcpu, bool store)
246{
247	struct kvm_run *run = vcpu->run;
248	u32 __user *opc = (u32 __user *) vcpu->arch.pc;
249	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
250	u32 cause = vcpu->arch.host_cp0_cause;
251	enum emulation_result er = EMULATE_DONE;
252	int ret = RESUME_GUEST;
253
254	if (((badvaddr & PAGE_MASK) == KVM_GUEST_COMMPAGE_ADDR)
255	    && KVM_GUEST_KERNEL_MODE(vcpu)) {
256		if (kvm_mips_handle_commpage_tlb_fault(badvaddr, vcpu) < 0) {
257			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
258			ret = RESUME_HOST;
259		}
260	} else if (KVM_GUEST_KSEGX(badvaddr) < KVM_GUEST_KSEG0
261		   || KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG23) {
262		kvm_debug("USER ADDR TLB %s fault: cause %#x, PC: %p, BadVaddr: %#lx\n",
263			  store ? "ST" : "LD", cause, opc, badvaddr);
264
265		/*
266		 * User Address (UA) fault, this could happen if
267		 * (1) TLB entry not present/valid in both Guest and shadow host
268		 *     TLBs, in this case we pass on the fault to the guest
269		 *     kernel and let it handle it.
270		 * (2) TLB entry is present in the Guest TLB but not in the
271		 *     shadow, in this case we inject the TLB from the Guest TLB
272		 *     into the shadow host TLB
273		 */
274
275		er = kvm_mips_handle_tlbmiss(cause, opc, vcpu, store);
276		if (er == EMULATE_DONE)
277			ret = RESUME_GUEST;
278		else {
279			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
280			ret = RESUME_HOST;
281		}
282	} else if (KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG0) {
283		/*
284		 * All KSEG0 faults are handled by KVM, as the guest kernel does
285		 * not expect to ever get them
286		 */
287		if (kvm_mips_handle_kseg0_tlb_fault(badvaddr, vcpu, store) < 0)
288			ret = kvm_mips_bad_access(cause, opc, vcpu, store);
289	} else if (KVM_GUEST_KERNEL_MODE(vcpu)
290		   && (KSEGX(badvaddr) == CKSEG0 || KSEGX(badvaddr) == CKSEG1)) {
291		/*
292		 * With EVA we may get a TLB exception instead of an address
293		 * error when the guest performs MMIO to KSeg1 addresses.
294		 */
295		ret = kvm_mips_bad_access(cause, opc, vcpu, store);
296	} else {
297		kvm_err("Illegal TLB %s fault address , cause %#x, PC: %p, BadVaddr: %#lx\n",
298			store ? "ST" : "LD", cause, opc, badvaddr);
299		kvm_mips_dump_host_tlbs();
300		kvm_arch_vcpu_dump_regs(vcpu);
301		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
302		ret = RESUME_HOST;
303	}
304	return ret;
305}
306
307static int kvm_trap_emul_handle_tlb_st_miss(struct kvm_vcpu *vcpu)
308{
309	return kvm_trap_emul_handle_tlb_miss(vcpu, true);
310}
311
312static int kvm_trap_emul_handle_tlb_ld_miss(struct kvm_vcpu *vcpu)
313{
314	return kvm_trap_emul_handle_tlb_miss(vcpu, false);
315}
316
317static int kvm_trap_emul_handle_addr_err_st(struct kvm_vcpu *vcpu)
318{
319	u32 __user *opc = (u32 __user *) vcpu->arch.pc;
320	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
321	u32 cause = vcpu->arch.host_cp0_cause;
322	int ret = RESUME_GUEST;
323
324	if (KVM_GUEST_KERNEL_MODE(vcpu)
325	    && (KSEGX(badvaddr) == CKSEG0 || KSEGX(badvaddr) == CKSEG1)) {
326		ret = kvm_mips_bad_store(cause, opc, vcpu);
327	} else {
328		kvm_err("Address Error (STORE): cause %#x, PC: %p, BadVaddr: %#lx\n",
329			cause, opc, badvaddr);
330		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
331		ret = RESUME_HOST;
332	}
333	return ret;
334}
335
336static int kvm_trap_emul_handle_addr_err_ld(struct kvm_vcpu *vcpu)
337{
338	u32 __user *opc = (u32 __user *) vcpu->arch.pc;
339	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
340	u32 cause = vcpu->arch.host_cp0_cause;
341	int ret = RESUME_GUEST;
342
343	if (KSEGX(badvaddr) == CKSEG0 || KSEGX(badvaddr) == CKSEG1) {
344		ret = kvm_mips_bad_load(cause, opc, vcpu);
345	} else {
346		kvm_err("Address Error (LOAD): cause %#x, PC: %p, BadVaddr: %#lx\n",
347			cause, opc, badvaddr);
348		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
349		ret = RESUME_HOST;
350	}
351	return ret;
352}
353
354static int kvm_trap_emul_handle_syscall(struct kvm_vcpu *vcpu)
355{
356	u32 __user *opc = (u32 __user *) vcpu->arch.pc;
357	u32 cause = vcpu->arch.host_cp0_cause;
358	enum emulation_result er = EMULATE_DONE;
359	int ret = RESUME_GUEST;
360
361	er = kvm_mips_emulate_syscall(cause, opc, vcpu);
362	if (er == EMULATE_DONE)
363		ret = RESUME_GUEST;
364	else {
365		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
366		ret = RESUME_HOST;
367	}
368	return ret;
369}
370
371static int kvm_trap_emul_handle_res_inst(struct kvm_vcpu *vcpu)
372{
373	u32 __user *opc = (u32 __user *) vcpu->arch.pc;
374	u32 cause = vcpu->arch.host_cp0_cause;
375	enum emulation_result er = EMULATE_DONE;
376	int ret = RESUME_GUEST;
377
378	er = kvm_mips_handle_ri(cause, opc, vcpu);
379	if (er == EMULATE_DONE)
380		ret = RESUME_GUEST;
381	else {
382		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
383		ret = RESUME_HOST;
384	}
385	return ret;
386}
387
388static int kvm_trap_emul_handle_break(struct kvm_vcpu *vcpu)
389{
390	u32 __user *opc = (u32 __user *) vcpu->arch.pc;
391	u32 cause = vcpu->arch.host_cp0_cause;
392	enum emulation_result er = EMULATE_DONE;
393	int ret = RESUME_GUEST;
394
395	er = kvm_mips_emulate_bp_exc(cause, opc, vcpu);
396	if (er == EMULATE_DONE)
397		ret = RESUME_GUEST;
398	else {
399		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
400		ret = RESUME_HOST;
401	}
402	return ret;
403}
404
405static int kvm_trap_emul_handle_trap(struct kvm_vcpu *vcpu)
406{
407	u32 __user *opc = (u32 __user *)vcpu->arch.pc;
408	u32 cause = vcpu->arch.host_cp0_cause;
409	enum emulation_result er = EMULATE_DONE;
410	int ret = RESUME_GUEST;
411
412	er = kvm_mips_emulate_trap_exc(cause, opc, vcpu);
413	if (er == EMULATE_DONE) {
414		ret = RESUME_GUEST;
415	} else {
416		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
417		ret = RESUME_HOST;
418	}
419	return ret;
420}
421
422static int kvm_trap_emul_handle_msa_fpe(struct kvm_vcpu *vcpu)
423{
424	u32 __user *opc = (u32 __user *)vcpu->arch.pc;
425	u32 cause = vcpu->arch.host_cp0_cause;
426	enum emulation_result er = EMULATE_DONE;
427	int ret = RESUME_GUEST;
428
429	er = kvm_mips_emulate_msafpe_exc(cause, opc, vcpu);
430	if (er == EMULATE_DONE) {
431		ret = RESUME_GUEST;
432	} else {
433		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
434		ret = RESUME_HOST;
435	}
436	return ret;
437}
438
439static int kvm_trap_emul_handle_fpe(struct kvm_vcpu *vcpu)
440{
441	u32 __user *opc = (u32 __user *)vcpu->arch.pc;
442	u32 cause = vcpu->arch.host_cp0_cause;
443	enum emulation_result er = EMULATE_DONE;
444	int ret = RESUME_GUEST;
445
446	er = kvm_mips_emulate_fpe_exc(cause, opc, vcpu);
447	if (er == EMULATE_DONE) {
448		ret = RESUME_GUEST;
449	} else {
450		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
451		ret = RESUME_HOST;
452	}
453	return ret;
454}
455
456/**
457 * kvm_trap_emul_handle_msa_disabled() - Guest used MSA while disabled in root.
458 * @vcpu:	Virtual CPU context.
459 *
460 * Handle when the guest attempts to use MSA when it is disabled.
461 */
462static int kvm_trap_emul_handle_msa_disabled(struct kvm_vcpu *vcpu)
463{
464	struct mips_coproc *cop0 = vcpu->arch.cop0;
465	u32 __user *opc = (u32 __user *) vcpu->arch.pc;
466	u32 cause = vcpu->arch.host_cp0_cause;
467	enum emulation_result er = EMULATE_DONE;
468	int ret = RESUME_GUEST;
469
470	if (!kvm_mips_guest_has_msa(&vcpu->arch) ||
471	    (kvm_read_c0_guest_status(cop0) & (ST0_CU1 | ST0_FR)) == ST0_CU1) {
472		/*
473		 * No MSA in guest, or FPU enabled and not in FR=1 mode,
474		 * guest reserved instruction exception
475		 */
476		er = kvm_mips_emulate_ri_exc(cause, opc, vcpu);
477	} else if (!(kvm_read_c0_guest_config5(cop0) & MIPS_CONF5_MSAEN)) {
478		/* MSA disabled by guest, guest MSA disabled exception */
479		er = kvm_mips_emulate_msadis_exc(cause, opc, vcpu);
480	} else {
481		/* Restore MSA/FPU state */
482		kvm_own_msa(vcpu);
483		er = EMULATE_DONE;
484	}
485
486	switch (er) {
487	case EMULATE_DONE:
488		ret = RESUME_GUEST;
489		break;
490
491	case EMULATE_FAIL:
492		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
493		ret = RESUME_HOST;
494		break;
495
496	default:
497		BUG();
498	}
499	return ret;
500}
501
502static int kvm_trap_emul_hardware_enable(void)
503{
504	return 0;
505}
506
507static void kvm_trap_emul_hardware_disable(void)
508{
509}
510
511static int kvm_trap_emul_check_extension(struct kvm *kvm, long ext)
512{
513	int r;
514
515	switch (ext) {
516	case KVM_CAP_MIPS_TE:
517		r = 1;
518		break;
519	case KVM_CAP_IOEVENTFD:
520		r = 1;
521		break;
522	default:
523		r = 0;
524		break;
525	}
526
527	return r;
528}
529
530static int kvm_trap_emul_vcpu_init(struct kvm_vcpu *vcpu)
531{
532	struct mm_struct *kern_mm = &vcpu->arch.guest_kernel_mm;
533	struct mm_struct *user_mm = &vcpu->arch.guest_user_mm;
534
535	/*
536	 * Allocate GVA -> HPA page tables.
537	 * MIPS doesn't use the mm_struct pointer argument.
538	 */
539	kern_mm->pgd = pgd_alloc(kern_mm);
540	if (!kern_mm->pgd)
541		return -ENOMEM;
542
543	user_mm->pgd = pgd_alloc(user_mm);
544	if (!user_mm->pgd) {
545		pgd_free(kern_mm, kern_mm->pgd);
546		return -ENOMEM;
547	}
548
549	return 0;
550}
551
552static void kvm_mips_emul_free_gva_pt(pgd_t *pgd)
553{
554	/* Don't free host kernel page tables copied from init_mm.pgd */
555	const unsigned long end = 0x80000000;
556	unsigned long pgd_va, pud_va, pmd_va;
557	p4d_t *p4d;
558	pud_t *pud;
559	pmd_t *pmd;
560	pte_t *pte;
561	int i, j, k;
562
563	for (i = 0; i < USER_PTRS_PER_PGD; i++) {
564		if (pgd_none(pgd[i]))
565			continue;
566
567		pgd_va = (unsigned long)i << PGDIR_SHIFT;
568		if (pgd_va >= end)
569			break;
570		p4d = p4d_offset(pgd, 0);
571		pud = pud_offset(p4d + i, 0);
572		for (j = 0; j < PTRS_PER_PUD; j++) {
573			if (pud_none(pud[j]))
574				continue;
575
576			pud_va = pgd_va | ((unsigned long)j << PUD_SHIFT);
577			if (pud_va >= end)
578				break;
579			pmd = pmd_offset(pud + j, 0);
580			for (k = 0; k < PTRS_PER_PMD; k++) {
581				if (pmd_none(pmd[k]))
582					continue;
583
584				pmd_va = pud_va | (k << PMD_SHIFT);
585				if (pmd_va >= end)
586					break;
587				pte = pte_offset_kernel(pmd + k, 0);
588				pte_free_kernel(NULL, pte);
589			}
590			pmd_free(NULL, pmd);
591		}
592		pud_free(NULL, pud);
593	}
594	pgd_free(NULL, pgd);
595}
596
597static void kvm_trap_emul_vcpu_uninit(struct kvm_vcpu *vcpu)
598{
599	kvm_mips_emul_free_gva_pt(vcpu->arch.guest_kernel_mm.pgd);
600	kvm_mips_emul_free_gva_pt(vcpu->arch.guest_user_mm.pgd);
601}
602
603static int kvm_trap_emul_vcpu_setup(struct kvm_vcpu *vcpu)
604{
605	struct mips_coproc *cop0 = vcpu->arch.cop0;
606	u32 config, config1;
607	int vcpu_id = vcpu->vcpu_id;
608
609	/* Start off the timer at 100 MHz */
610	kvm_mips_init_count(vcpu, 100*1000*1000);
611
612	/*
613	 * Arch specific stuff, set up config registers properly so that the
614	 * guest will come up as expected
615	 */
616#ifndef CONFIG_CPU_MIPSR6
617	/* r2-r5, simulate a MIPS 24kc */
618	kvm_write_c0_guest_prid(cop0, 0x00019300);
619#else
620	/* r6+, simulate a generic QEMU machine */
621	kvm_write_c0_guest_prid(cop0, 0x00010000);
622#endif
623	/*
624	 * Have config1, Cacheable, noncoherent, write-back, write allocate.
625	 * Endianness, arch revision & virtually tagged icache should match
626	 * host.
627	 */
628	config = read_c0_config() & MIPS_CONF_AR;
629	config |= MIPS_CONF_M | CONF_CM_CACHABLE_NONCOHERENT | MIPS_CONF_MT_TLB;
630#ifdef CONFIG_CPU_BIG_ENDIAN
631	config |= CONF_BE;
632#endif
633	if (cpu_has_vtag_icache)
634		config |= MIPS_CONF_VI;
635	kvm_write_c0_guest_config(cop0, config);
636
637	/* Read the cache characteristics from the host Config1 Register */
638	config1 = (read_c0_config1() & ~0x7f);
639
640	/* DCache line size not correctly reported in Config1 on Octeon CPUs */
641	if (cpu_dcache_line_size()) {
642		config1 &= ~MIPS_CONF1_DL;
643		config1 |= ((ilog2(cpu_dcache_line_size()) - 1) <<
644			    MIPS_CONF1_DL_SHF) & MIPS_CONF1_DL;
645	}
646
647	/* Set up MMU size */
648	config1 &= ~(0x3f << 25);
649	config1 |= ((KVM_MIPS_GUEST_TLB_SIZE - 1) << 25);
650
651	/* We unset some bits that we aren't emulating */
652	config1 &= ~(MIPS_CONF1_C2 | MIPS_CONF1_MD | MIPS_CONF1_PC |
653		     MIPS_CONF1_WR | MIPS_CONF1_CA);
654	kvm_write_c0_guest_config1(cop0, config1);
655
656	/* Have config3, no tertiary/secondary caches implemented */
657	kvm_write_c0_guest_config2(cop0, MIPS_CONF_M);
658	/* MIPS_CONF_M | (read_c0_config2() & 0xfff) */
659
660	/* Have config4, UserLocal */
661	kvm_write_c0_guest_config3(cop0, MIPS_CONF_M | MIPS_CONF3_ULRI);
662
663	/* Have config5 */
664	kvm_write_c0_guest_config4(cop0, MIPS_CONF_M);
665
666	/* No config6 */
667	kvm_write_c0_guest_config5(cop0, 0);
668
669	/* Set Wait IE/IXMT Ignore in Config7, IAR, AR */
670	kvm_write_c0_guest_config7(cop0, (MIPS_CONF7_WII) | (1 << 10));
671
672	/* Status */
673	kvm_write_c0_guest_status(cop0, ST0_BEV | ST0_ERL);
674
675	/*
676	 * Setup IntCtl defaults, compatibility mode for timer interrupts (HW5)
677	 */
678	kvm_write_c0_guest_intctl(cop0, 0xFC000000);
679
680	/* Put in vcpu id as CPUNum into Ebase Reg to handle SMP Guests */
681	kvm_write_c0_guest_ebase(cop0, KVM_GUEST_KSEG0 |
682				       (vcpu_id & MIPS_EBASE_CPUNUM));
683
684	/* Put PC at guest reset vector */
685	vcpu->arch.pc = KVM_GUEST_CKSEG1ADDR(0x1fc00000);
686
687	return 0;
688}
689
690static void kvm_trap_emul_flush_shadow_all(struct kvm *kvm)
691{
692	/* Flush GVA page tables and invalidate GVA ASIDs on all VCPUs */
693	kvm_flush_remote_tlbs(kvm);
694}
695
696static void kvm_trap_emul_flush_shadow_memslot(struct kvm *kvm,
697					const struct kvm_memory_slot *slot)
698{
699	kvm_trap_emul_flush_shadow_all(kvm);
700}
701
702static u64 kvm_trap_emul_get_one_regs[] = {
703	KVM_REG_MIPS_CP0_INDEX,
704	KVM_REG_MIPS_CP0_ENTRYLO0,
705	KVM_REG_MIPS_CP0_ENTRYLO1,
706	KVM_REG_MIPS_CP0_CONTEXT,
707	KVM_REG_MIPS_CP0_USERLOCAL,
708	KVM_REG_MIPS_CP0_PAGEMASK,
709	KVM_REG_MIPS_CP0_WIRED,
710	KVM_REG_MIPS_CP0_HWRENA,
711	KVM_REG_MIPS_CP0_BADVADDR,
712	KVM_REG_MIPS_CP0_COUNT,
713	KVM_REG_MIPS_CP0_ENTRYHI,
714	KVM_REG_MIPS_CP0_COMPARE,
715	KVM_REG_MIPS_CP0_STATUS,
716	KVM_REG_MIPS_CP0_INTCTL,
717	KVM_REG_MIPS_CP0_CAUSE,
718	KVM_REG_MIPS_CP0_EPC,
719	KVM_REG_MIPS_CP0_PRID,
720	KVM_REG_MIPS_CP0_EBASE,
721	KVM_REG_MIPS_CP0_CONFIG,
722	KVM_REG_MIPS_CP0_CONFIG1,
723	KVM_REG_MIPS_CP0_CONFIG2,
724	KVM_REG_MIPS_CP0_CONFIG3,
725	KVM_REG_MIPS_CP0_CONFIG4,
726	KVM_REG_MIPS_CP0_CONFIG5,
727	KVM_REG_MIPS_CP0_CONFIG7,
728	KVM_REG_MIPS_CP0_ERROREPC,
729	KVM_REG_MIPS_CP0_KSCRATCH1,
730	KVM_REG_MIPS_CP0_KSCRATCH2,
731	KVM_REG_MIPS_CP0_KSCRATCH3,
732	KVM_REG_MIPS_CP0_KSCRATCH4,
733	KVM_REG_MIPS_CP0_KSCRATCH5,
734	KVM_REG_MIPS_CP0_KSCRATCH6,
735
736	KVM_REG_MIPS_COUNT_CTL,
737	KVM_REG_MIPS_COUNT_RESUME,
738	KVM_REG_MIPS_COUNT_HZ,
739};
740
741static unsigned long kvm_trap_emul_num_regs(struct kvm_vcpu *vcpu)
742{
743	return ARRAY_SIZE(kvm_trap_emul_get_one_regs);
744}
745
746static int kvm_trap_emul_copy_reg_indices(struct kvm_vcpu *vcpu,
747					  u64 __user *indices)
748{
749	if (copy_to_user(indices, kvm_trap_emul_get_one_regs,
750			 sizeof(kvm_trap_emul_get_one_regs)))
751		return -EFAULT;
752	indices += ARRAY_SIZE(kvm_trap_emul_get_one_regs);
753
754	return 0;
755}
756
757static int kvm_trap_emul_get_one_reg(struct kvm_vcpu *vcpu,
758				     const struct kvm_one_reg *reg,
759				     s64 *v)
760{
761	struct mips_coproc *cop0 = vcpu->arch.cop0;
762
763	switch (reg->id) {
764	case KVM_REG_MIPS_CP0_INDEX:
765		*v = (long)kvm_read_c0_guest_index(cop0);
766		break;
767	case KVM_REG_MIPS_CP0_ENTRYLO0:
768		*v = kvm_read_c0_guest_entrylo0(cop0);
769		break;
770	case KVM_REG_MIPS_CP0_ENTRYLO1:
771		*v = kvm_read_c0_guest_entrylo1(cop0);
772		break;
773	case KVM_REG_MIPS_CP0_CONTEXT:
774		*v = (long)kvm_read_c0_guest_context(cop0);
775		break;
776	case KVM_REG_MIPS_CP0_USERLOCAL:
777		*v = (long)kvm_read_c0_guest_userlocal(cop0);
778		break;
779	case KVM_REG_MIPS_CP0_PAGEMASK:
780		*v = (long)kvm_read_c0_guest_pagemask(cop0);
781		break;
782	case KVM_REG_MIPS_CP0_WIRED:
783		*v = (long)kvm_read_c0_guest_wired(cop0);
784		break;
785	case KVM_REG_MIPS_CP0_HWRENA:
786		*v = (long)kvm_read_c0_guest_hwrena(cop0);
787		break;
788	case KVM_REG_MIPS_CP0_BADVADDR:
789		*v = (long)kvm_read_c0_guest_badvaddr(cop0);
790		break;
791	case KVM_REG_MIPS_CP0_ENTRYHI:
792		*v = (long)kvm_read_c0_guest_entryhi(cop0);
793		break;
794	case KVM_REG_MIPS_CP0_COMPARE:
795		*v = (long)kvm_read_c0_guest_compare(cop0);
796		break;
797	case KVM_REG_MIPS_CP0_STATUS:
798		*v = (long)kvm_read_c0_guest_status(cop0);
799		break;
800	case KVM_REG_MIPS_CP0_INTCTL:
801		*v = (long)kvm_read_c0_guest_intctl(cop0);
802		break;
803	case KVM_REG_MIPS_CP0_CAUSE:
804		*v = (long)kvm_read_c0_guest_cause(cop0);
805		break;
806	case KVM_REG_MIPS_CP0_EPC:
807		*v = (long)kvm_read_c0_guest_epc(cop0);
808		break;
809	case KVM_REG_MIPS_CP0_PRID:
810		*v = (long)kvm_read_c0_guest_prid(cop0);
811		break;
812	case KVM_REG_MIPS_CP0_EBASE:
813		*v = (long)kvm_read_c0_guest_ebase(cop0);
814		break;
815	case KVM_REG_MIPS_CP0_CONFIG:
816		*v = (long)kvm_read_c0_guest_config(cop0);
817		break;
818	case KVM_REG_MIPS_CP0_CONFIG1:
819		*v = (long)kvm_read_c0_guest_config1(cop0);
820		break;
821	case KVM_REG_MIPS_CP0_CONFIG2:
822		*v = (long)kvm_read_c0_guest_config2(cop0);
823		break;
824	case KVM_REG_MIPS_CP0_CONFIG3:
825		*v = (long)kvm_read_c0_guest_config3(cop0);
826		break;
827	case KVM_REG_MIPS_CP0_CONFIG4:
828		*v = (long)kvm_read_c0_guest_config4(cop0);
829		break;
830	case KVM_REG_MIPS_CP0_CONFIG5:
831		*v = (long)kvm_read_c0_guest_config5(cop0);
832		break;
833	case KVM_REG_MIPS_CP0_CONFIG7:
834		*v = (long)kvm_read_c0_guest_config7(cop0);
835		break;
836	case KVM_REG_MIPS_CP0_COUNT:
837		*v = kvm_mips_read_count(vcpu);
838		break;
839	case KVM_REG_MIPS_COUNT_CTL:
840		*v = vcpu->arch.count_ctl;
841		break;
842	case KVM_REG_MIPS_COUNT_RESUME:
843		*v = ktime_to_ns(vcpu->arch.count_resume);
844		break;
845	case KVM_REG_MIPS_COUNT_HZ:
846		*v = vcpu->arch.count_hz;
847		break;
848	case KVM_REG_MIPS_CP0_ERROREPC:
849		*v = (long)kvm_read_c0_guest_errorepc(cop0);
850		break;
851	case KVM_REG_MIPS_CP0_KSCRATCH1:
852		*v = (long)kvm_read_c0_guest_kscratch1(cop0);
853		break;
854	case KVM_REG_MIPS_CP0_KSCRATCH2:
855		*v = (long)kvm_read_c0_guest_kscratch2(cop0);
856		break;
857	case KVM_REG_MIPS_CP0_KSCRATCH3:
858		*v = (long)kvm_read_c0_guest_kscratch3(cop0);
859		break;
860	case KVM_REG_MIPS_CP0_KSCRATCH4:
861		*v = (long)kvm_read_c0_guest_kscratch4(cop0);
862		break;
863	case KVM_REG_MIPS_CP0_KSCRATCH5:
864		*v = (long)kvm_read_c0_guest_kscratch5(cop0);
865		break;
866	case KVM_REG_MIPS_CP0_KSCRATCH6:
867		*v = (long)kvm_read_c0_guest_kscratch6(cop0);
868		break;
869	default:
870		return -EINVAL;
871	}
872	return 0;
873}
874
875static int kvm_trap_emul_set_one_reg(struct kvm_vcpu *vcpu,
876				     const struct kvm_one_reg *reg,
877				     s64 v)
878{
879	struct mips_coproc *cop0 = vcpu->arch.cop0;
880	int ret = 0;
881	unsigned int cur, change;
882
883	switch (reg->id) {
884	case KVM_REG_MIPS_CP0_INDEX:
885		kvm_write_c0_guest_index(cop0, v);
886		break;
887	case KVM_REG_MIPS_CP0_ENTRYLO0:
888		kvm_write_c0_guest_entrylo0(cop0, v);
889		break;
890	case KVM_REG_MIPS_CP0_ENTRYLO1:
891		kvm_write_c0_guest_entrylo1(cop0, v);
892		break;
893	case KVM_REG_MIPS_CP0_CONTEXT:
894		kvm_write_c0_guest_context(cop0, v);
895		break;
896	case KVM_REG_MIPS_CP0_USERLOCAL:
897		kvm_write_c0_guest_userlocal(cop0, v);
898		break;
899	case KVM_REG_MIPS_CP0_PAGEMASK:
900		kvm_write_c0_guest_pagemask(cop0, v);
901		break;
902	case KVM_REG_MIPS_CP0_WIRED:
903		kvm_write_c0_guest_wired(cop0, v);
904		break;
905	case KVM_REG_MIPS_CP0_HWRENA:
906		kvm_write_c0_guest_hwrena(cop0, v);
907		break;
908	case KVM_REG_MIPS_CP0_BADVADDR:
909		kvm_write_c0_guest_badvaddr(cop0, v);
910		break;
911	case KVM_REG_MIPS_CP0_ENTRYHI:
912		kvm_write_c0_guest_entryhi(cop0, v);
913		break;
914	case KVM_REG_MIPS_CP0_STATUS:
915		kvm_write_c0_guest_status(cop0, v);
916		break;
917	case KVM_REG_MIPS_CP0_INTCTL:
918		/* No VInt, so no VS, read-only for now */
919		break;
920	case KVM_REG_MIPS_CP0_EPC:
921		kvm_write_c0_guest_epc(cop0, v);
922		break;
923	case KVM_REG_MIPS_CP0_PRID:
924		kvm_write_c0_guest_prid(cop0, v);
925		break;
926	case KVM_REG_MIPS_CP0_EBASE:
927		/*
928		 * Allow core number to be written, but the exception base must
929		 * remain in guest KSeg0.
930		 */
931		kvm_change_c0_guest_ebase(cop0, 0x1ffff000 | MIPS_EBASE_CPUNUM,
932					  v);
933		break;
934	case KVM_REG_MIPS_CP0_COUNT:
935		kvm_mips_write_count(vcpu, v);
936		break;
937	case KVM_REG_MIPS_CP0_COMPARE:
938		kvm_mips_write_compare(vcpu, v, false);
939		break;
940	case KVM_REG_MIPS_CP0_CAUSE:
941		/*
942		 * If the timer is stopped or started (DC bit) it must look
943		 * atomic with changes to the interrupt pending bits (TI, IRQ5).
944		 * A timer interrupt should not happen in between.
945		 */
946		if ((kvm_read_c0_guest_cause(cop0) ^ v) & CAUSEF_DC) {
947			if (v & CAUSEF_DC) {
948				/* disable timer first */
949				kvm_mips_count_disable_cause(vcpu);
950				kvm_change_c0_guest_cause(cop0, (u32)~CAUSEF_DC,
951							  v);
952			} else {
953				/* enable timer last */
954				kvm_change_c0_guest_cause(cop0, (u32)~CAUSEF_DC,
955							  v);
956				kvm_mips_count_enable_cause(vcpu);
957			}
958		} else {
959			kvm_write_c0_guest_cause(cop0, v);
960		}
961		break;
962	case KVM_REG_MIPS_CP0_CONFIG:
963		/* read-only for now */
964		break;
965	case KVM_REG_MIPS_CP0_CONFIG1:
966		cur = kvm_read_c0_guest_config1(cop0);
967		change = (cur ^ v) & kvm_mips_config1_wrmask(vcpu);
968		if (change) {
969			v = cur ^ change;
970			kvm_write_c0_guest_config1(cop0, v);
971		}
972		break;
973	case KVM_REG_MIPS_CP0_CONFIG2:
974		/* read-only for now */
975		break;
976	case KVM_REG_MIPS_CP0_CONFIG3:
977		cur = kvm_read_c0_guest_config3(cop0);
978		change = (cur ^ v) & kvm_mips_config3_wrmask(vcpu);
979		if (change) {
980			v = cur ^ change;
981			kvm_write_c0_guest_config3(cop0, v);
982		}
983		break;
984	case KVM_REG_MIPS_CP0_CONFIG4:
985		cur = kvm_read_c0_guest_config4(cop0);
986		change = (cur ^ v) & kvm_mips_config4_wrmask(vcpu);
987		if (change) {
988			v = cur ^ change;
989			kvm_write_c0_guest_config4(cop0, v);
990		}
991		break;
992	case KVM_REG_MIPS_CP0_CONFIG5:
993		cur = kvm_read_c0_guest_config5(cop0);
994		change = (cur ^ v) & kvm_mips_config5_wrmask(vcpu);
995		if (change) {
996			v = cur ^ change;
997			kvm_write_c0_guest_config5(cop0, v);
998		}
999		break;
1000	case KVM_REG_MIPS_CP0_CONFIG7:
1001		/* writes ignored */
1002		break;
1003	case KVM_REG_MIPS_COUNT_CTL:
1004		ret = kvm_mips_set_count_ctl(vcpu, v);
1005		break;
1006	case KVM_REG_MIPS_COUNT_RESUME:
1007		ret = kvm_mips_set_count_resume(vcpu, v);
1008		break;
1009	case KVM_REG_MIPS_COUNT_HZ:
1010		ret = kvm_mips_set_count_hz(vcpu, v);
1011		break;
1012	case KVM_REG_MIPS_CP0_ERROREPC:
1013		kvm_write_c0_guest_errorepc(cop0, v);
1014		break;
1015	case KVM_REG_MIPS_CP0_KSCRATCH1:
1016		kvm_write_c0_guest_kscratch1(cop0, v);
1017		break;
1018	case KVM_REG_MIPS_CP0_KSCRATCH2:
1019		kvm_write_c0_guest_kscratch2(cop0, v);
1020		break;
1021	case KVM_REG_MIPS_CP0_KSCRATCH3:
1022		kvm_write_c0_guest_kscratch3(cop0, v);
1023		break;
1024	case KVM_REG_MIPS_CP0_KSCRATCH4:
1025		kvm_write_c0_guest_kscratch4(cop0, v);
1026		break;
1027	case KVM_REG_MIPS_CP0_KSCRATCH5:
1028		kvm_write_c0_guest_kscratch5(cop0, v);
1029		break;
1030	case KVM_REG_MIPS_CP0_KSCRATCH6:
1031		kvm_write_c0_guest_kscratch6(cop0, v);
1032		break;
1033	default:
1034		return -EINVAL;
1035	}
1036	return ret;
1037}
1038
1039static int kvm_trap_emul_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
1040{
1041	struct mm_struct *kern_mm = &vcpu->arch.guest_kernel_mm;
1042	struct mm_struct *user_mm = &vcpu->arch.guest_user_mm;
1043	struct mm_struct *mm;
1044
1045	/*
1046	 * Were we in guest context? If so, restore the appropriate ASID based
1047	 * on the mode of the Guest (Kernel/User).
1048	 */
1049	if (current->flags & PF_VCPU) {
1050		mm = KVM_GUEST_KERNEL_MODE(vcpu) ? kern_mm : user_mm;
1051		check_switch_mmu_context(mm);
1052		kvm_mips_suspend_mm(cpu);
1053		ehb();
1054	}
1055
1056	return 0;
1057}
1058
1059static int kvm_trap_emul_vcpu_put(struct kvm_vcpu *vcpu, int cpu)
1060{
1061	kvm_lose_fpu(vcpu);
1062
1063	if (current->flags & PF_VCPU) {
1064		/* Restore normal Linux process memory map */
1065		check_switch_mmu_context(current->mm);
1066		kvm_mips_resume_mm(cpu);
1067		ehb();
1068	}
1069
1070	return 0;
1071}
1072
1073static void kvm_trap_emul_check_requests(struct kvm_vcpu *vcpu, int cpu,
1074					 bool reload_asid)
1075{
1076	struct mm_struct *kern_mm = &vcpu->arch.guest_kernel_mm;
1077	struct mm_struct *user_mm = &vcpu->arch.guest_user_mm;
1078	struct mm_struct *mm;
1079	int i;
1080
1081	if (likely(!kvm_request_pending(vcpu)))
1082		return;
1083
1084	if (kvm_check_request(KVM_REQ_TLB_FLUSH, vcpu)) {
1085		/*
1086		 * Both kernel & user GVA mappings must be invalidated. The
1087		 * caller is just about to check whether the ASID is stale
1088		 * anyway so no need to reload it here.
1089		 */
1090		kvm_mips_flush_gva_pt(kern_mm->pgd, KMF_GPA | KMF_KERN);
1091		kvm_mips_flush_gva_pt(user_mm->pgd, KMF_GPA | KMF_USER);
1092		for_each_possible_cpu(i) {
1093			set_cpu_context(i, kern_mm, 0);
1094			set_cpu_context(i, user_mm, 0);
1095		}
1096
1097		/* Generate new ASID for current mode */
1098		if (reload_asid) {
1099			mm = KVM_GUEST_KERNEL_MODE(vcpu) ? kern_mm : user_mm;
1100			get_new_mmu_context(mm);
1101			htw_stop();
1102			write_c0_entryhi(cpu_asid(cpu, mm));
1103			TLBMISS_HANDLER_SETUP_PGD(mm->pgd);
1104			htw_start();
1105		}
1106	}
1107}
1108
1109/**
1110 * kvm_trap_emul_gva_lockless_begin() - Begin lockless access to GVA space.
1111 * @vcpu:	VCPU pointer.
1112 *
1113 * Call before a GVA space access outside of guest mode, to ensure that
1114 * asynchronous TLB flush requests are handled or delayed until completion of
1115 * the GVA access (as indicated by a matching kvm_trap_emul_gva_lockless_end()).
1116 *
1117 * Should be called with IRQs already enabled.
1118 */
1119void kvm_trap_emul_gva_lockless_begin(struct kvm_vcpu *vcpu)
1120{
1121	/* We re-enable IRQs in kvm_trap_emul_gva_lockless_end() */
1122	WARN_ON_ONCE(irqs_disabled());
1123
1124	/*
1125	 * The caller is about to access the GVA space, so we set the mode to
1126	 * force TLB flush requests to send an IPI, and also disable IRQs to
1127	 * delay IPI handling until kvm_trap_emul_gva_lockless_end().
1128	 */
1129	local_irq_disable();
1130
1131	/*
1132	 * Make sure the read of VCPU requests is not reordered ahead of the
1133	 * write to vcpu->mode, or we could miss a TLB flush request while
1134	 * the requester sees the VCPU as outside of guest mode and not needing
1135	 * an IPI.
1136	 */
1137	smp_store_mb(vcpu->mode, READING_SHADOW_PAGE_TABLES);
1138
1139	/*
1140	 * If a TLB flush has been requested (potentially while
1141	 * OUTSIDE_GUEST_MODE and assumed immediately effective), perform it
1142	 * before accessing the GVA space, and be sure to reload the ASID if
1143	 * necessary as it'll be immediately used.
1144	 *
1145	 * TLB flush requests after this check will trigger an IPI due to the
1146	 * mode change above, which will be delayed due to IRQs disabled.
1147	 */
1148	kvm_trap_emul_check_requests(vcpu, smp_processor_id(), true);
1149}
1150
1151/**
1152 * kvm_trap_emul_gva_lockless_end() - End lockless access to GVA space.
1153 * @vcpu:	VCPU pointer.
1154 *
1155 * Called after a GVA space access outside of guest mode. Should have a matching
1156 * call to kvm_trap_emul_gva_lockless_begin().
1157 */
1158void kvm_trap_emul_gva_lockless_end(struct kvm_vcpu *vcpu)
1159{
1160	/*
1161	 * Make sure the write to vcpu->mode is not reordered in front of GVA
1162	 * accesses, or a TLB flush requester may not think it necessary to send
1163	 * an IPI.
1164	 */
1165	smp_store_release(&vcpu->mode, OUTSIDE_GUEST_MODE);
1166
1167	/*
1168	 * Now that the access to GVA space is complete, its safe for pending
1169	 * TLB flush request IPIs to be handled (which indicates completion).
1170	 */
1171	local_irq_enable();
1172}
1173
1174static void kvm_trap_emul_vcpu_reenter(struct kvm_vcpu *vcpu)
1175{
1176	struct mm_struct *kern_mm = &vcpu->arch.guest_kernel_mm;
1177	struct mm_struct *user_mm = &vcpu->arch.guest_user_mm;
1178	struct mm_struct *mm;
1179	struct mips_coproc *cop0 = vcpu->arch.cop0;
1180	int i, cpu = smp_processor_id();
1181	unsigned int gasid;
1182
1183	/*
1184	 * No need to reload ASID, IRQs are disabled already so there's no rush,
1185	 * and we'll check if we need to regenerate below anyway before
1186	 * re-entering the guest.
1187	 */
1188	kvm_trap_emul_check_requests(vcpu, cpu, false);
1189
1190	if (KVM_GUEST_KERNEL_MODE(vcpu)) {
1191		mm = kern_mm;
1192	} else {
1193		mm = user_mm;
1194
1195		/*
1196		 * Lazy host ASID regeneration / PT flush for guest user mode.
1197		 * If the guest ASID has changed since the last guest usermode
1198		 * execution, invalidate the stale TLB entries and flush GVA PT
1199		 * entries too.
1200		 */
1201		gasid = kvm_read_c0_guest_entryhi(cop0) & KVM_ENTRYHI_ASID;
1202		if (gasid != vcpu->arch.last_user_gasid) {
1203			kvm_mips_flush_gva_pt(user_mm->pgd, KMF_USER);
1204			for_each_possible_cpu(i)
1205				set_cpu_context(i, user_mm, 0);
1206			vcpu->arch.last_user_gasid = gasid;
1207		}
1208	}
1209
1210	/*
1211	 * Check if ASID is stale. This may happen due to a TLB flush request or
1212	 * a lazy user MM invalidation.
1213	 */
1214	check_mmu_context(mm);
1215}
1216
1217static int kvm_trap_emul_vcpu_run(struct kvm_vcpu *vcpu)
1218{
1219	int cpu = smp_processor_id();
1220	int r;
1221
1222	/* Check if we have any exceptions/interrupts pending */
1223	kvm_mips_deliver_interrupts(vcpu,
1224				    kvm_read_c0_guest_cause(vcpu->arch.cop0));
1225
1226	kvm_trap_emul_vcpu_reenter(vcpu);
1227
1228	/*
1229	 * We use user accessors to access guest memory, but we don't want to
1230	 * invoke Linux page faulting.
1231	 */
1232	pagefault_disable();
1233
1234	/* Disable hardware page table walking while in guest */
1235	htw_stop();
1236
1237	/*
1238	 * While in guest context we're in the guest's address space, not the
1239	 * host process address space, so we need to be careful not to confuse
1240	 * e.g. cache management IPIs.
1241	 */
1242	kvm_mips_suspend_mm(cpu);
1243
1244	r = vcpu->arch.vcpu_run(vcpu);
1245
1246	/* We may have migrated while handling guest exits */
1247	cpu = smp_processor_id();
1248
1249	/* Restore normal Linux process memory map */
1250	check_switch_mmu_context(current->mm);
1251	kvm_mips_resume_mm(cpu);
1252
1253	htw_start();
1254
1255	pagefault_enable();
1256
1257	return r;
1258}
1259
1260static struct kvm_mips_callbacks kvm_trap_emul_callbacks = {
1261	/* exit handlers */
1262	.handle_cop_unusable = kvm_trap_emul_handle_cop_unusable,
1263	.handle_tlb_mod = kvm_trap_emul_handle_tlb_mod,
1264	.handle_tlb_st_miss = kvm_trap_emul_handle_tlb_st_miss,
1265	.handle_tlb_ld_miss = kvm_trap_emul_handle_tlb_ld_miss,
1266	.handle_addr_err_st = kvm_trap_emul_handle_addr_err_st,
1267	.handle_addr_err_ld = kvm_trap_emul_handle_addr_err_ld,
1268	.handle_syscall = kvm_trap_emul_handle_syscall,
1269	.handle_res_inst = kvm_trap_emul_handle_res_inst,
1270	.handle_break = kvm_trap_emul_handle_break,
1271	.handle_trap = kvm_trap_emul_handle_trap,
1272	.handle_msa_fpe = kvm_trap_emul_handle_msa_fpe,
1273	.handle_fpe = kvm_trap_emul_handle_fpe,
1274	.handle_msa_disabled = kvm_trap_emul_handle_msa_disabled,
1275	.handle_guest_exit = kvm_trap_emul_no_handler,
1276
1277	.hardware_enable = kvm_trap_emul_hardware_enable,
1278	.hardware_disable = kvm_trap_emul_hardware_disable,
1279	.check_extension = kvm_trap_emul_check_extension,
1280	.vcpu_init = kvm_trap_emul_vcpu_init,
1281	.vcpu_uninit = kvm_trap_emul_vcpu_uninit,
1282	.vcpu_setup = kvm_trap_emul_vcpu_setup,
1283	.flush_shadow_all = kvm_trap_emul_flush_shadow_all,
1284	.flush_shadow_memslot = kvm_trap_emul_flush_shadow_memslot,
1285	.gva_to_gpa = kvm_trap_emul_gva_to_gpa_cb,
1286	.queue_timer_int = kvm_mips_queue_timer_int_cb,
1287	.dequeue_timer_int = kvm_mips_dequeue_timer_int_cb,
1288	.queue_io_int = kvm_mips_queue_io_int_cb,
1289	.dequeue_io_int = kvm_mips_dequeue_io_int_cb,
1290	.irq_deliver = kvm_mips_irq_deliver_cb,
1291	.irq_clear = kvm_mips_irq_clear_cb,
1292	.num_regs = kvm_trap_emul_num_regs,
1293	.copy_reg_indices = kvm_trap_emul_copy_reg_indices,
1294	.get_one_reg = kvm_trap_emul_get_one_reg,
1295	.set_one_reg = kvm_trap_emul_set_one_reg,
1296	.vcpu_load = kvm_trap_emul_vcpu_load,
1297	.vcpu_put = kvm_trap_emul_vcpu_put,
1298	.vcpu_run = kvm_trap_emul_vcpu_run,
1299	.vcpu_reenter = kvm_trap_emul_vcpu_reenter,
1300};
1301
1302int kvm_mips_emulation_init(struct kvm_mips_callbacks **install_callbacks)
1303{
1304	*install_callbacks = &kvm_trap_emul_callbacks;
1305	return 0;
1306}
1307