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: MIPS specific KVM APIs
7 *
8 * Copyright (C) 2012  MIPS Technologies, Inc.  All rights reserved.
9 * Authors: Sanjay Lal <sanjayl@kymasys.com>
10 */
11
12#include <linux/bitops.h>
13#include <linux/errno.h>
14#include <linux/err.h>
15#include <linux/kdebug.h>
16#include <linux/module.h>
17#include <linux/uaccess.h>
18#include <linux/vmalloc.h>
19#include <linux/sched/signal.h>
20#include <linux/fs.h>
21#include <linux/memblock.h>
22#include <linux/pgtable.h>
23
24#include <asm/fpu.h>
25#include <asm/page.h>
26#include <asm/cacheflush.h>
27#include <asm/mmu_context.h>
28#include <asm/pgalloc.h>
29
30#include <linux/kvm_host.h>
31
32#include "interrupt.h"
33
34#define CREATE_TRACE_POINTS
35#include "trace.h"
36
37#ifndef VECTORSPACING
38#define VECTORSPACING 0x100	/* for EI/VI mode */
39#endif
40
41const struct _kvm_stats_desc kvm_vm_stats_desc[] = {
42	KVM_GENERIC_VM_STATS()
43};
44
45const struct kvm_stats_header kvm_vm_stats_header = {
46	.name_size = KVM_STATS_NAME_SIZE,
47	.num_desc = ARRAY_SIZE(kvm_vm_stats_desc),
48	.id_offset = sizeof(struct kvm_stats_header),
49	.desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE,
50	.data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE +
51		       sizeof(kvm_vm_stats_desc),
52};
53
54const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = {
55	KVM_GENERIC_VCPU_STATS(),
56	STATS_DESC_COUNTER(VCPU, wait_exits),
57	STATS_DESC_COUNTER(VCPU, cache_exits),
58	STATS_DESC_COUNTER(VCPU, signal_exits),
59	STATS_DESC_COUNTER(VCPU, int_exits),
60	STATS_DESC_COUNTER(VCPU, cop_unusable_exits),
61	STATS_DESC_COUNTER(VCPU, tlbmod_exits),
62	STATS_DESC_COUNTER(VCPU, tlbmiss_ld_exits),
63	STATS_DESC_COUNTER(VCPU, tlbmiss_st_exits),
64	STATS_DESC_COUNTER(VCPU, addrerr_st_exits),
65	STATS_DESC_COUNTER(VCPU, addrerr_ld_exits),
66	STATS_DESC_COUNTER(VCPU, syscall_exits),
67	STATS_DESC_COUNTER(VCPU, resvd_inst_exits),
68	STATS_DESC_COUNTER(VCPU, break_inst_exits),
69	STATS_DESC_COUNTER(VCPU, trap_inst_exits),
70	STATS_DESC_COUNTER(VCPU, msa_fpe_exits),
71	STATS_DESC_COUNTER(VCPU, fpe_exits),
72	STATS_DESC_COUNTER(VCPU, msa_disabled_exits),
73	STATS_DESC_COUNTER(VCPU, flush_dcache_exits),
74	STATS_DESC_COUNTER(VCPU, vz_gpsi_exits),
75	STATS_DESC_COUNTER(VCPU, vz_gsfc_exits),
76	STATS_DESC_COUNTER(VCPU, vz_hc_exits),
77	STATS_DESC_COUNTER(VCPU, vz_grr_exits),
78	STATS_DESC_COUNTER(VCPU, vz_gva_exits),
79	STATS_DESC_COUNTER(VCPU, vz_ghfc_exits),
80	STATS_DESC_COUNTER(VCPU, vz_gpa_exits),
81	STATS_DESC_COUNTER(VCPU, vz_resvd_exits),
82#ifdef CONFIG_CPU_LOONGSON64
83	STATS_DESC_COUNTER(VCPU, vz_cpucfg_exits),
84#endif
85};
86
87const struct kvm_stats_header kvm_vcpu_stats_header = {
88	.name_size = KVM_STATS_NAME_SIZE,
89	.num_desc = ARRAY_SIZE(kvm_vcpu_stats_desc),
90	.id_offset = sizeof(struct kvm_stats_header),
91	.desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE,
92	.data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE +
93		       sizeof(kvm_vcpu_stats_desc),
94};
95
96bool kvm_trace_guest_mode_change;
97
98int kvm_guest_mode_change_trace_reg(void)
99{
100	kvm_trace_guest_mode_change = true;
101	return 0;
102}
103
104void kvm_guest_mode_change_trace_unreg(void)
105{
106	kvm_trace_guest_mode_change = false;
107}
108
109/*
110 * XXXKYMA: We are simulatoring a processor that has the WII bit set in
111 * Config7, so we are "runnable" if interrupts are pending
112 */
113int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
114{
115	return !!(vcpu->arch.pending_exceptions);
116}
117
118bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
119{
120	return false;
121}
122
123int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
124{
125	return 1;
126}
127
128int kvm_arch_hardware_enable(void)
129{
130	return kvm_mips_callbacks->hardware_enable();
131}
132
133void kvm_arch_hardware_disable(void)
134{
135	kvm_mips_callbacks->hardware_disable();
136}
137
138extern void kvm_init_loongson_ipi(struct kvm *kvm);
139
140int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
141{
142	switch (type) {
143	case KVM_VM_MIPS_AUTO:
144		break;
145	case KVM_VM_MIPS_VZ:
146		break;
147	default:
148		/* Unsupported KVM type */
149		return -EINVAL;
150	}
151
152	/* Allocate page table to map GPA -> RPA */
153	kvm->arch.gpa_mm.pgd = kvm_pgd_alloc();
154	if (!kvm->arch.gpa_mm.pgd)
155		return -ENOMEM;
156
157#ifdef CONFIG_CPU_LOONGSON64
158	kvm_init_loongson_ipi(kvm);
159#endif
160
161	return 0;
162}
163
164static void kvm_mips_free_gpa_pt(struct kvm *kvm)
165{
166	/* It should always be safe to remove after flushing the whole range */
167	WARN_ON(!kvm_mips_flush_gpa_pt(kvm, 0, ~0));
168	pgd_free(NULL, kvm->arch.gpa_mm.pgd);
169}
170
171void kvm_arch_destroy_vm(struct kvm *kvm)
172{
173	kvm_destroy_vcpus(kvm);
174	kvm_mips_free_gpa_pt(kvm);
175}
176
177long kvm_arch_dev_ioctl(struct file *filp, unsigned int ioctl,
178			unsigned long arg)
179{
180	return -ENOIOCTLCMD;
181}
182
183void kvm_arch_flush_shadow_all(struct kvm *kvm)
184{
185	/* Flush whole GPA */
186	kvm_mips_flush_gpa_pt(kvm, 0, ~0);
187	kvm_flush_remote_tlbs(kvm);
188}
189
190void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
191				   struct kvm_memory_slot *slot)
192{
193	/*
194	 * The slot has been made invalid (ready for moving or deletion), so we
195	 * need to ensure that it can no longer be accessed by any guest VCPUs.
196	 */
197
198	spin_lock(&kvm->mmu_lock);
199	/* Flush slot from GPA */
200	kvm_mips_flush_gpa_pt(kvm, slot->base_gfn,
201			      slot->base_gfn + slot->npages - 1);
202	kvm_flush_remote_tlbs_memslot(kvm, slot);
203	spin_unlock(&kvm->mmu_lock);
204}
205
206int kvm_arch_prepare_memory_region(struct kvm *kvm,
207				   const struct kvm_memory_slot *old,
208				   struct kvm_memory_slot *new,
209				   enum kvm_mr_change change)
210{
211	return 0;
212}
213
214void kvm_arch_commit_memory_region(struct kvm *kvm,
215				   struct kvm_memory_slot *old,
216				   const struct kvm_memory_slot *new,
217				   enum kvm_mr_change change)
218{
219	int needs_flush;
220
221	/*
222	 * If dirty page logging is enabled, write protect all pages in the slot
223	 * ready for dirty logging.
224	 *
225	 * There is no need to do this in any of the following cases:
226	 * CREATE:	No dirty mappings will already exist.
227	 * MOVE/DELETE:	The old mappings will already have been cleaned up by
228	 *		kvm_arch_flush_shadow_memslot()
229	 */
230	if (change == KVM_MR_FLAGS_ONLY &&
231	    (!(old->flags & KVM_MEM_LOG_DIRTY_PAGES) &&
232	     new->flags & KVM_MEM_LOG_DIRTY_PAGES)) {
233		spin_lock(&kvm->mmu_lock);
234		/* Write protect GPA page table entries */
235		needs_flush = kvm_mips_mkclean_gpa_pt(kvm, new->base_gfn,
236					new->base_gfn + new->npages - 1);
237		if (needs_flush)
238			kvm_flush_remote_tlbs_memslot(kvm, new);
239		spin_unlock(&kvm->mmu_lock);
240	}
241}
242
243static inline void dump_handler(const char *symbol, void *start, void *end)
244{
245	u32 *p;
246
247	pr_debug("LEAF(%s)\n", symbol);
248
249	pr_debug("\t.set push\n");
250	pr_debug("\t.set noreorder\n");
251
252	for (p = start; p < (u32 *)end; ++p)
253		pr_debug("\t.word\t0x%08x\t\t# %p\n", *p, p);
254
255	pr_debug("\t.set\tpop\n");
256
257	pr_debug("\tEND(%s)\n", symbol);
258}
259
260/* low level hrtimer wake routine */
261static enum hrtimer_restart kvm_mips_comparecount_wakeup(struct hrtimer *timer)
262{
263	struct kvm_vcpu *vcpu;
264
265	vcpu = container_of(timer, struct kvm_vcpu, arch.comparecount_timer);
266
267	kvm_mips_callbacks->queue_timer_int(vcpu);
268
269	vcpu->arch.wait = 0;
270	rcuwait_wake_up(&vcpu->wait);
271
272	return kvm_mips_count_timeout(vcpu);
273}
274
275int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
276{
277	return 0;
278}
279
280int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
281{
282	int err, size;
283	void *gebase, *p, *handler, *refill_start, *refill_end;
284	int i;
285
286	kvm_debug("kvm @ %p: create cpu %d at %p\n",
287		  vcpu->kvm, vcpu->vcpu_id, vcpu);
288
289	err = kvm_mips_callbacks->vcpu_init(vcpu);
290	if (err)
291		return err;
292
293	hrtimer_init(&vcpu->arch.comparecount_timer, CLOCK_MONOTONIC,
294		     HRTIMER_MODE_REL);
295	vcpu->arch.comparecount_timer.function = kvm_mips_comparecount_wakeup;
296
297	/*
298	 * Allocate space for host mode exception handlers that handle
299	 * guest mode exits
300	 */
301	if (cpu_has_veic || cpu_has_vint)
302		size = 0x200 + VECTORSPACING * 64;
303	else
304		size = 0x4000;
305
306	gebase = kzalloc(ALIGN(size, PAGE_SIZE), GFP_KERNEL);
307
308	if (!gebase) {
309		err = -ENOMEM;
310		goto out_uninit_vcpu;
311	}
312	kvm_debug("Allocated %d bytes for KVM Exception Handlers @ %p\n",
313		  ALIGN(size, PAGE_SIZE), gebase);
314
315	/*
316	 * Check new ebase actually fits in CP0_EBase. The lack of a write gate
317	 * limits us to the low 512MB of physical address space. If the memory
318	 * we allocate is out of range, just give up now.
319	 */
320	if (!cpu_has_ebase_wg && virt_to_phys(gebase) >= 0x20000000) {
321		kvm_err("CP0_EBase.WG required for guest exception base %pK\n",
322			gebase);
323		err = -ENOMEM;
324		goto out_free_gebase;
325	}
326
327	/* Save new ebase */
328	vcpu->arch.guest_ebase = gebase;
329
330	/* Build guest exception vectors dynamically in unmapped memory */
331	handler = gebase + 0x2000;
332
333	/* TLB refill (or XTLB refill on 64-bit VZ where KX=1) */
334	refill_start = gebase;
335	if (IS_ENABLED(CONFIG_64BIT))
336		refill_start += 0x080;
337	refill_end = kvm_mips_build_tlb_refill_exception(refill_start, handler);
338
339	/* General Exception Entry point */
340	kvm_mips_build_exception(gebase + 0x180, handler);
341
342	/* For vectored interrupts poke the exception code @ all offsets 0-7 */
343	for (i = 0; i < 8; i++) {
344		kvm_debug("L1 Vectored handler @ %p\n",
345			  gebase + 0x200 + (i * VECTORSPACING));
346		kvm_mips_build_exception(gebase + 0x200 + i * VECTORSPACING,
347					 handler);
348	}
349
350	/* General exit handler */
351	p = handler;
352	p = kvm_mips_build_exit(p);
353
354	/* Guest entry routine */
355	vcpu->arch.vcpu_run = p;
356	p = kvm_mips_build_vcpu_run(p);
357
358	/* Dump the generated code */
359	pr_debug("#include <asm/asm.h>\n");
360	pr_debug("#include <asm/regdef.h>\n");
361	pr_debug("\n");
362	dump_handler("kvm_vcpu_run", vcpu->arch.vcpu_run, p);
363	dump_handler("kvm_tlb_refill", refill_start, refill_end);
364	dump_handler("kvm_gen_exc", gebase + 0x180, gebase + 0x200);
365	dump_handler("kvm_exit", gebase + 0x2000, vcpu->arch.vcpu_run);
366
367	/* Invalidate the icache for these ranges */
368	flush_icache_range((unsigned long)gebase,
369			   (unsigned long)gebase + ALIGN(size, PAGE_SIZE));
370
371	/* Init */
372	vcpu->arch.last_sched_cpu = -1;
373	vcpu->arch.last_exec_cpu = -1;
374
375	/* Initial guest state */
376	err = kvm_mips_callbacks->vcpu_setup(vcpu);
377	if (err)
378		goto out_free_gebase;
379
380	return 0;
381
382out_free_gebase:
383	kfree(gebase);
384out_uninit_vcpu:
385	kvm_mips_callbacks->vcpu_uninit(vcpu);
386	return err;
387}
388
389void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
390{
391	hrtimer_cancel(&vcpu->arch.comparecount_timer);
392
393	kvm_mips_dump_stats(vcpu);
394
395	kvm_mmu_free_memory_caches(vcpu);
396	kfree(vcpu->arch.guest_ebase);
397
398	kvm_mips_callbacks->vcpu_uninit(vcpu);
399}
400
401int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
402					struct kvm_guest_debug *dbg)
403{
404	return -ENOIOCTLCMD;
405}
406
407/*
408 * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while
409 * the vCPU is running.
410 *
411 * This must be noinstr as instrumentation may make use of RCU, and this is not
412 * safe during the EQS.
413 */
414static int noinstr kvm_mips_vcpu_enter_exit(struct kvm_vcpu *vcpu)
415{
416	int ret;
417
418	guest_state_enter_irqoff();
419	ret = kvm_mips_callbacks->vcpu_run(vcpu);
420	guest_state_exit_irqoff();
421
422	return ret;
423}
424
425int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
426{
427	int r = -EINTR;
428
429	vcpu_load(vcpu);
430
431	kvm_sigset_activate(vcpu);
432
433	if (vcpu->mmio_needed) {
434		if (!vcpu->mmio_is_write)
435			kvm_mips_complete_mmio_load(vcpu);
436		vcpu->mmio_needed = 0;
437	}
438
439	if (vcpu->run->immediate_exit)
440		goto out;
441
442	lose_fpu(1);
443
444	local_irq_disable();
445	guest_timing_enter_irqoff();
446	trace_kvm_enter(vcpu);
447
448	/*
449	 * Make sure the read of VCPU requests in vcpu_run() callback is not
450	 * reordered ahead of the write to vcpu->mode, or we could miss a TLB
451	 * flush request while the requester sees the VCPU as outside of guest
452	 * mode and not needing an IPI.
453	 */
454	smp_store_mb(vcpu->mode, IN_GUEST_MODE);
455
456	r = kvm_mips_vcpu_enter_exit(vcpu);
457
458	/*
459	 * We must ensure that any pending interrupts are taken before
460	 * we exit guest timing so that timer ticks are accounted as
461	 * guest time. Transiently unmask interrupts so that any
462	 * pending interrupts are taken.
463	 *
464	 * TODO: is there a barrier which ensures that pending interrupts are
465	 * recognised? Currently this just hopes that the CPU takes any pending
466	 * interrupts between the enable and disable.
467	 */
468	local_irq_enable();
469	local_irq_disable();
470
471	trace_kvm_out(vcpu);
472	guest_timing_exit_irqoff();
473	local_irq_enable();
474
475out:
476	kvm_sigset_deactivate(vcpu);
477
478	vcpu_put(vcpu);
479	return r;
480}
481
482int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
483			     struct kvm_mips_interrupt *irq)
484{
485	int intr = (int)irq->irq;
486	struct kvm_vcpu *dvcpu = NULL;
487
488	if (intr == kvm_priority_to_irq[MIPS_EXC_INT_IPI_1] ||
489	    intr == kvm_priority_to_irq[MIPS_EXC_INT_IPI_2] ||
490	    intr == (-kvm_priority_to_irq[MIPS_EXC_INT_IPI_1]) ||
491	    intr == (-kvm_priority_to_irq[MIPS_EXC_INT_IPI_2]))
492		kvm_debug("%s: CPU: %d, INTR: %d\n", __func__, irq->cpu,
493			  (int)intr);
494
495	if (irq->cpu == -1)
496		dvcpu = vcpu;
497	else
498		dvcpu = kvm_get_vcpu(vcpu->kvm, irq->cpu);
499
500	if (intr == 2 || intr == 3 || intr == 4 || intr == 6) {
501		kvm_mips_callbacks->queue_io_int(dvcpu, irq);
502
503	} else if (intr == -2 || intr == -3 || intr == -4 || intr == -6) {
504		kvm_mips_callbacks->dequeue_io_int(dvcpu, irq);
505	} else {
506		kvm_err("%s: invalid interrupt ioctl (%d:%d)\n", __func__,
507			irq->cpu, irq->irq);
508		return -EINVAL;
509	}
510
511	dvcpu->arch.wait = 0;
512
513	rcuwait_wake_up(&dvcpu->wait);
514
515	return 0;
516}
517
518int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
519				    struct kvm_mp_state *mp_state)
520{
521	return -ENOIOCTLCMD;
522}
523
524int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
525				    struct kvm_mp_state *mp_state)
526{
527	return -ENOIOCTLCMD;
528}
529
530static u64 kvm_mips_get_one_regs[] = {
531	KVM_REG_MIPS_R0,
532	KVM_REG_MIPS_R1,
533	KVM_REG_MIPS_R2,
534	KVM_REG_MIPS_R3,
535	KVM_REG_MIPS_R4,
536	KVM_REG_MIPS_R5,
537	KVM_REG_MIPS_R6,
538	KVM_REG_MIPS_R7,
539	KVM_REG_MIPS_R8,
540	KVM_REG_MIPS_R9,
541	KVM_REG_MIPS_R10,
542	KVM_REG_MIPS_R11,
543	KVM_REG_MIPS_R12,
544	KVM_REG_MIPS_R13,
545	KVM_REG_MIPS_R14,
546	KVM_REG_MIPS_R15,
547	KVM_REG_MIPS_R16,
548	KVM_REG_MIPS_R17,
549	KVM_REG_MIPS_R18,
550	KVM_REG_MIPS_R19,
551	KVM_REG_MIPS_R20,
552	KVM_REG_MIPS_R21,
553	KVM_REG_MIPS_R22,
554	KVM_REG_MIPS_R23,
555	KVM_REG_MIPS_R24,
556	KVM_REG_MIPS_R25,
557	KVM_REG_MIPS_R26,
558	KVM_REG_MIPS_R27,
559	KVM_REG_MIPS_R28,
560	KVM_REG_MIPS_R29,
561	KVM_REG_MIPS_R30,
562	KVM_REG_MIPS_R31,
563
564#ifndef CONFIG_CPU_MIPSR6
565	KVM_REG_MIPS_HI,
566	KVM_REG_MIPS_LO,
567#endif
568	KVM_REG_MIPS_PC,
569};
570
571static u64 kvm_mips_get_one_regs_fpu[] = {
572	KVM_REG_MIPS_FCR_IR,
573	KVM_REG_MIPS_FCR_CSR,
574};
575
576static u64 kvm_mips_get_one_regs_msa[] = {
577	KVM_REG_MIPS_MSA_IR,
578	KVM_REG_MIPS_MSA_CSR,
579};
580
581static unsigned long kvm_mips_num_regs(struct kvm_vcpu *vcpu)
582{
583	unsigned long ret;
584
585	ret = ARRAY_SIZE(kvm_mips_get_one_regs);
586	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
587		ret += ARRAY_SIZE(kvm_mips_get_one_regs_fpu) + 48;
588		/* odd doubles */
589		if (boot_cpu_data.fpu_id & MIPS_FPIR_F64)
590			ret += 16;
591	}
592	if (kvm_mips_guest_can_have_msa(&vcpu->arch))
593		ret += ARRAY_SIZE(kvm_mips_get_one_regs_msa) + 32;
594	ret += kvm_mips_callbacks->num_regs(vcpu);
595
596	return ret;
597}
598
599static int kvm_mips_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices)
600{
601	u64 index;
602	unsigned int i;
603
604	if (copy_to_user(indices, kvm_mips_get_one_regs,
605			 sizeof(kvm_mips_get_one_regs)))
606		return -EFAULT;
607	indices += ARRAY_SIZE(kvm_mips_get_one_regs);
608
609	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
610		if (copy_to_user(indices, kvm_mips_get_one_regs_fpu,
611				 sizeof(kvm_mips_get_one_regs_fpu)))
612			return -EFAULT;
613		indices += ARRAY_SIZE(kvm_mips_get_one_regs_fpu);
614
615		for (i = 0; i < 32; ++i) {
616			index = KVM_REG_MIPS_FPR_32(i);
617			if (copy_to_user(indices, &index, sizeof(index)))
618				return -EFAULT;
619			++indices;
620
621			/* skip odd doubles if no F64 */
622			if (i & 1 && !(boot_cpu_data.fpu_id & MIPS_FPIR_F64))
623				continue;
624
625			index = KVM_REG_MIPS_FPR_64(i);
626			if (copy_to_user(indices, &index, sizeof(index)))
627				return -EFAULT;
628			++indices;
629		}
630	}
631
632	if (kvm_mips_guest_can_have_msa(&vcpu->arch)) {
633		if (copy_to_user(indices, kvm_mips_get_one_regs_msa,
634				 sizeof(kvm_mips_get_one_regs_msa)))
635			return -EFAULT;
636		indices += ARRAY_SIZE(kvm_mips_get_one_regs_msa);
637
638		for (i = 0; i < 32; ++i) {
639			index = KVM_REG_MIPS_VEC_128(i);
640			if (copy_to_user(indices, &index, sizeof(index)))
641				return -EFAULT;
642			++indices;
643		}
644	}
645
646	return kvm_mips_callbacks->copy_reg_indices(vcpu, indices);
647}
648
649static int kvm_mips_get_reg(struct kvm_vcpu *vcpu,
650			    const struct kvm_one_reg *reg)
651{
652	struct mips_coproc *cop0 = &vcpu->arch.cop0;
653	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
654	int ret;
655	s64 v;
656	s64 vs[2];
657	unsigned int idx;
658
659	switch (reg->id) {
660	/* General purpose registers */
661	case KVM_REG_MIPS_R0 ... KVM_REG_MIPS_R31:
662		v = (long)vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0];
663		break;
664#ifndef CONFIG_CPU_MIPSR6
665	case KVM_REG_MIPS_HI:
666		v = (long)vcpu->arch.hi;
667		break;
668	case KVM_REG_MIPS_LO:
669		v = (long)vcpu->arch.lo;
670		break;
671#endif
672	case KVM_REG_MIPS_PC:
673		v = (long)vcpu->arch.pc;
674		break;
675
676	/* Floating point registers */
677	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
678		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
679			return -EINVAL;
680		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
681		/* Odd singles in top of even double when FR=0 */
682		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
683			v = get_fpr32(&fpu->fpr[idx], 0);
684		else
685			v = get_fpr32(&fpu->fpr[idx & ~1], idx & 1);
686		break;
687	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
688		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
689			return -EINVAL;
690		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
691		/* Can't access odd doubles in FR=0 mode */
692		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
693			return -EINVAL;
694		v = get_fpr64(&fpu->fpr[idx], 0);
695		break;
696	case KVM_REG_MIPS_FCR_IR:
697		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
698			return -EINVAL;
699		v = boot_cpu_data.fpu_id;
700		break;
701	case KVM_REG_MIPS_FCR_CSR:
702		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
703			return -EINVAL;
704		v = fpu->fcr31;
705		break;
706
707	/* MIPS SIMD Architecture (MSA) registers */
708	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
709		if (!kvm_mips_guest_has_msa(&vcpu->arch))
710			return -EINVAL;
711		/* Can't access MSA registers in FR=0 mode */
712		if (!(kvm_read_c0_guest_status(cop0) & ST0_FR))
713			return -EINVAL;
714		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
715#ifdef CONFIG_CPU_LITTLE_ENDIAN
716		/* least significant byte first */
717		vs[0] = get_fpr64(&fpu->fpr[idx], 0);
718		vs[1] = get_fpr64(&fpu->fpr[idx], 1);
719#else
720		/* most significant byte first */
721		vs[0] = get_fpr64(&fpu->fpr[idx], 1);
722		vs[1] = get_fpr64(&fpu->fpr[idx], 0);
723#endif
724		break;
725	case KVM_REG_MIPS_MSA_IR:
726		if (!kvm_mips_guest_has_msa(&vcpu->arch))
727			return -EINVAL;
728		v = boot_cpu_data.msa_id;
729		break;
730	case KVM_REG_MIPS_MSA_CSR:
731		if (!kvm_mips_guest_has_msa(&vcpu->arch))
732			return -EINVAL;
733		v = fpu->msacsr;
734		break;
735
736	/* registers to be handled specially */
737	default:
738		ret = kvm_mips_callbacks->get_one_reg(vcpu, reg, &v);
739		if (ret)
740			return ret;
741		break;
742	}
743	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
744		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
745
746		return put_user(v, uaddr64);
747	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
748		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
749		u32 v32 = (u32)v;
750
751		return put_user(v32, uaddr32);
752	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
753		void __user *uaddr = (void __user *)(long)reg->addr;
754
755		return copy_to_user(uaddr, vs, 16) ? -EFAULT : 0;
756	} else {
757		return -EINVAL;
758	}
759}
760
761static int kvm_mips_set_reg(struct kvm_vcpu *vcpu,
762			    const struct kvm_one_reg *reg)
763{
764	struct mips_coproc *cop0 = &vcpu->arch.cop0;
765	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
766	s64 v;
767	s64 vs[2];
768	unsigned int idx;
769
770	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
771		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
772
773		if (get_user(v, uaddr64) != 0)
774			return -EFAULT;
775	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
776		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
777		s32 v32;
778
779		if (get_user(v32, uaddr32) != 0)
780			return -EFAULT;
781		v = (s64)v32;
782	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
783		void __user *uaddr = (void __user *)(long)reg->addr;
784
785		return copy_from_user(vs, uaddr, 16) ? -EFAULT : 0;
786	} else {
787		return -EINVAL;
788	}
789
790	switch (reg->id) {
791	/* General purpose registers */
792	case KVM_REG_MIPS_R0:
793		/* Silently ignore requests to set $0 */
794		break;
795	case KVM_REG_MIPS_R1 ... KVM_REG_MIPS_R31:
796		vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0] = v;
797		break;
798#ifndef CONFIG_CPU_MIPSR6
799	case KVM_REG_MIPS_HI:
800		vcpu->arch.hi = v;
801		break;
802	case KVM_REG_MIPS_LO:
803		vcpu->arch.lo = v;
804		break;
805#endif
806	case KVM_REG_MIPS_PC:
807		vcpu->arch.pc = v;
808		break;
809
810	/* Floating point registers */
811	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
812		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
813			return -EINVAL;
814		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
815		/* Odd singles in top of even double when FR=0 */
816		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
817			set_fpr32(&fpu->fpr[idx], 0, v);
818		else
819			set_fpr32(&fpu->fpr[idx & ~1], idx & 1, v);
820		break;
821	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
822		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
823			return -EINVAL;
824		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
825		/* Can't access odd doubles in FR=0 mode */
826		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
827			return -EINVAL;
828		set_fpr64(&fpu->fpr[idx], 0, v);
829		break;
830	case KVM_REG_MIPS_FCR_IR:
831		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
832			return -EINVAL;
833		/* Read-only */
834		break;
835	case KVM_REG_MIPS_FCR_CSR:
836		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
837			return -EINVAL;
838		fpu->fcr31 = v;
839		break;
840
841	/* MIPS SIMD Architecture (MSA) registers */
842	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
843		if (!kvm_mips_guest_has_msa(&vcpu->arch))
844			return -EINVAL;
845		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
846#ifdef CONFIG_CPU_LITTLE_ENDIAN
847		/* least significant byte first */
848		set_fpr64(&fpu->fpr[idx], 0, vs[0]);
849		set_fpr64(&fpu->fpr[idx], 1, vs[1]);
850#else
851		/* most significant byte first */
852		set_fpr64(&fpu->fpr[idx], 1, vs[0]);
853		set_fpr64(&fpu->fpr[idx], 0, vs[1]);
854#endif
855		break;
856	case KVM_REG_MIPS_MSA_IR:
857		if (!kvm_mips_guest_has_msa(&vcpu->arch))
858			return -EINVAL;
859		/* Read-only */
860		break;
861	case KVM_REG_MIPS_MSA_CSR:
862		if (!kvm_mips_guest_has_msa(&vcpu->arch))
863			return -EINVAL;
864		fpu->msacsr = v;
865		break;
866
867	/* registers to be handled specially */
868	default:
869		return kvm_mips_callbacks->set_one_reg(vcpu, reg, v);
870	}
871	return 0;
872}
873
874static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
875				     struct kvm_enable_cap *cap)
876{
877	int r = 0;
878
879	if (!kvm_vm_ioctl_check_extension(vcpu->kvm, cap->cap))
880		return -EINVAL;
881	if (cap->flags)
882		return -EINVAL;
883	if (cap->args[0])
884		return -EINVAL;
885
886	switch (cap->cap) {
887	case KVM_CAP_MIPS_FPU:
888		vcpu->arch.fpu_enabled = true;
889		break;
890	case KVM_CAP_MIPS_MSA:
891		vcpu->arch.msa_enabled = true;
892		break;
893	default:
894		r = -EINVAL;
895		break;
896	}
897
898	return r;
899}
900
901long kvm_arch_vcpu_async_ioctl(struct file *filp, unsigned int ioctl,
902			       unsigned long arg)
903{
904	struct kvm_vcpu *vcpu = filp->private_data;
905	void __user *argp = (void __user *)arg;
906
907	if (ioctl == KVM_INTERRUPT) {
908		struct kvm_mips_interrupt irq;
909
910		if (copy_from_user(&irq, argp, sizeof(irq)))
911			return -EFAULT;
912		kvm_debug("[%d] %s: irq: %d\n", vcpu->vcpu_id, __func__,
913			  irq.irq);
914
915		return kvm_vcpu_ioctl_interrupt(vcpu, &irq);
916	}
917
918	return -ENOIOCTLCMD;
919}
920
921long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl,
922			 unsigned long arg)
923{
924	struct kvm_vcpu *vcpu = filp->private_data;
925	void __user *argp = (void __user *)arg;
926	long r;
927
928	vcpu_load(vcpu);
929
930	switch (ioctl) {
931	case KVM_SET_ONE_REG:
932	case KVM_GET_ONE_REG: {
933		struct kvm_one_reg reg;
934
935		r = -EFAULT;
936		if (copy_from_user(&reg, argp, sizeof(reg)))
937			break;
938		if (ioctl == KVM_SET_ONE_REG)
939			r = kvm_mips_set_reg(vcpu, &reg);
940		else
941			r = kvm_mips_get_reg(vcpu, &reg);
942		break;
943	}
944	case KVM_GET_REG_LIST: {
945		struct kvm_reg_list __user *user_list = argp;
946		struct kvm_reg_list reg_list;
947		unsigned n;
948
949		r = -EFAULT;
950		if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
951			break;
952		n = reg_list.n;
953		reg_list.n = kvm_mips_num_regs(vcpu);
954		if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
955			break;
956		r = -E2BIG;
957		if (n < reg_list.n)
958			break;
959		r = kvm_mips_copy_reg_indices(vcpu, user_list->reg);
960		break;
961	}
962	case KVM_ENABLE_CAP: {
963		struct kvm_enable_cap cap;
964
965		r = -EFAULT;
966		if (copy_from_user(&cap, argp, sizeof(cap)))
967			break;
968		r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
969		break;
970	}
971	default:
972		r = -ENOIOCTLCMD;
973	}
974
975	vcpu_put(vcpu);
976	return r;
977}
978
979void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
980{
981
982}
983
984int kvm_arch_flush_remote_tlbs(struct kvm *kvm)
985{
986	kvm_mips_callbacks->prepare_flush_shadow(kvm);
987	return 1;
988}
989
990int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
991{
992	int r;
993
994	switch (ioctl) {
995	default:
996		r = -ENOIOCTLCMD;
997	}
998
999	return r;
1000}
1001
1002int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
1003				  struct kvm_sregs *sregs)
1004{
1005	return -ENOIOCTLCMD;
1006}
1007
1008int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
1009				  struct kvm_sregs *sregs)
1010{
1011	return -ENOIOCTLCMD;
1012}
1013
1014void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
1015{
1016}
1017
1018int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1019{
1020	return -ENOIOCTLCMD;
1021}
1022
1023int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1024{
1025	return -ENOIOCTLCMD;
1026}
1027
1028vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
1029{
1030	return VM_FAULT_SIGBUS;
1031}
1032
1033int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
1034{
1035	int r;
1036
1037	switch (ext) {
1038	case KVM_CAP_ONE_REG:
1039	case KVM_CAP_ENABLE_CAP:
1040	case KVM_CAP_READONLY_MEM:
1041	case KVM_CAP_SYNC_MMU:
1042	case KVM_CAP_IMMEDIATE_EXIT:
1043		r = 1;
1044		break;
1045	case KVM_CAP_NR_VCPUS:
1046		r = min_t(unsigned int, num_online_cpus(), KVM_MAX_VCPUS);
1047		break;
1048	case KVM_CAP_MAX_VCPUS:
1049		r = KVM_MAX_VCPUS;
1050		break;
1051	case KVM_CAP_MAX_VCPU_ID:
1052		r = KVM_MAX_VCPU_IDS;
1053		break;
1054	case KVM_CAP_MIPS_FPU:
1055		/* We don't handle systems with inconsistent cpu_has_fpu */
1056		r = !!raw_cpu_has_fpu;
1057		break;
1058	case KVM_CAP_MIPS_MSA:
1059		/*
1060		 * We don't support MSA vector partitioning yet:
1061		 * 1) It would require explicit support which can't be tested
1062		 *    yet due to lack of support in current hardware.
1063		 * 2) It extends the state that would need to be saved/restored
1064		 *    by e.g. QEMU for migration.
1065		 *
1066		 * When vector partitioning hardware becomes available, support
1067		 * could be added by requiring a flag when enabling
1068		 * KVM_CAP_MIPS_MSA capability to indicate that userland knows
1069		 * to save/restore the appropriate extra state.
1070		 */
1071		r = cpu_has_msa && !(boot_cpu_data.msa_id & MSA_IR_WRPF);
1072		break;
1073	default:
1074		r = kvm_mips_callbacks->check_extension(kvm, ext);
1075		break;
1076	}
1077	return r;
1078}
1079
1080int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
1081{
1082	return kvm_mips_pending_timer(vcpu) ||
1083		kvm_read_c0_guest_cause(&vcpu->arch.cop0) & C_TI;
1084}
1085
1086int kvm_arch_vcpu_dump_regs(struct kvm_vcpu *vcpu)
1087{
1088	int i;
1089	struct mips_coproc *cop0;
1090
1091	if (!vcpu)
1092		return -1;
1093
1094	kvm_debug("VCPU Register Dump:\n");
1095	kvm_debug("\tpc = 0x%08lx\n", vcpu->arch.pc);
1096	kvm_debug("\texceptions: %08lx\n", vcpu->arch.pending_exceptions);
1097
1098	for (i = 0; i < 32; i += 4) {
1099		kvm_debug("\tgpr%02d: %08lx %08lx %08lx %08lx\n", i,
1100		       vcpu->arch.gprs[i],
1101		       vcpu->arch.gprs[i + 1],
1102		       vcpu->arch.gprs[i + 2], vcpu->arch.gprs[i + 3]);
1103	}
1104	kvm_debug("\thi: 0x%08lx\n", vcpu->arch.hi);
1105	kvm_debug("\tlo: 0x%08lx\n", vcpu->arch.lo);
1106
1107	cop0 = &vcpu->arch.cop0;
1108	kvm_debug("\tStatus: 0x%08x, Cause: 0x%08x\n",
1109		  kvm_read_c0_guest_status(cop0),
1110		  kvm_read_c0_guest_cause(cop0));
1111
1112	kvm_debug("\tEPC: 0x%08lx\n", kvm_read_c0_guest_epc(cop0));
1113
1114	return 0;
1115}
1116
1117int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1118{
1119	int i;
1120
1121	vcpu_load(vcpu);
1122
1123	for (i = 1; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1124		vcpu->arch.gprs[i] = regs->gpr[i];
1125	vcpu->arch.gprs[0] = 0; /* zero is special, and cannot be set. */
1126	vcpu->arch.hi = regs->hi;
1127	vcpu->arch.lo = regs->lo;
1128	vcpu->arch.pc = regs->pc;
1129
1130	vcpu_put(vcpu);
1131	return 0;
1132}
1133
1134int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1135{
1136	int i;
1137
1138	vcpu_load(vcpu);
1139
1140	for (i = 0; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1141		regs->gpr[i] = vcpu->arch.gprs[i];
1142
1143	regs->hi = vcpu->arch.hi;
1144	regs->lo = vcpu->arch.lo;
1145	regs->pc = vcpu->arch.pc;
1146
1147	vcpu_put(vcpu);
1148	return 0;
1149}
1150
1151int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
1152				  struct kvm_translation *tr)
1153{
1154	return 0;
1155}
1156
1157static void kvm_mips_set_c0_status(void)
1158{
1159	u32 status = read_c0_status();
1160
1161	if (cpu_has_dsp)
1162		status |= (ST0_MX);
1163
1164	write_c0_status(status);
1165	ehb();
1166}
1167
1168/*
1169 * Return value is in the form (errcode<<2 | RESUME_FLAG_HOST | RESUME_FLAG_NV)
1170 */
1171static int __kvm_mips_handle_exit(struct kvm_vcpu *vcpu)
1172{
1173	struct kvm_run *run = vcpu->run;
1174	u32 cause = vcpu->arch.host_cp0_cause;
1175	u32 exccode = (cause >> CAUSEB_EXCCODE) & 0x1f;
1176	u32 __user *opc = (u32 __user *) vcpu->arch.pc;
1177	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
1178	enum emulation_result er = EMULATE_DONE;
1179	u32 inst;
1180	int ret = RESUME_GUEST;
1181
1182	vcpu->mode = OUTSIDE_GUEST_MODE;
1183
1184	/* Set a default exit reason */
1185	run->exit_reason = KVM_EXIT_UNKNOWN;
1186	run->ready_for_interrupt_injection = 1;
1187
1188	/*
1189	 * Set the appropriate status bits based on host CPU features,
1190	 * before we hit the scheduler
1191	 */
1192	kvm_mips_set_c0_status();
1193
1194	local_irq_enable();
1195
1196	kvm_debug("kvm_mips_handle_exit: cause: %#x, PC: %p, kvm_run: %p, kvm_vcpu: %p\n",
1197			cause, opc, run, vcpu);
1198	trace_kvm_exit(vcpu, exccode);
1199
1200	switch (exccode) {
1201	case EXCCODE_INT:
1202		kvm_debug("[%d]EXCCODE_INT @ %p\n", vcpu->vcpu_id, opc);
1203
1204		++vcpu->stat.int_exits;
1205
1206		if (need_resched())
1207			cond_resched();
1208
1209		ret = RESUME_GUEST;
1210		break;
1211
1212	case EXCCODE_CPU:
1213		kvm_debug("EXCCODE_CPU: @ PC: %p\n", opc);
1214
1215		++vcpu->stat.cop_unusable_exits;
1216		ret = kvm_mips_callbacks->handle_cop_unusable(vcpu);
1217		/* XXXKYMA: Might need to return to user space */
1218		if (run->exit_reason == KVM_EXIT_IRQ_WINDOW_OPEN)
1219			ret = RESUME_HOST;
1220		break;
1221
1222	case EXCCODE_MOD:
1223		++vcpu->stat.tlbmod_exits;
1224		ret = kvm_mips_callbacks->handle_tlb_mod(vcpu);
1225		break;
1226
1227	case EXCCODE_TLBS:
1228		kvm_debug("TLB ST fault:  cause %#x, status %#x, PC: %p, BadVaddr: %#lx\n",
1229			  cause, kvm_read_c0_guest_status(&vcpu->arch.cop0), opc,
1230			  badvaddr);
1231
1232		++vcpu->stat.tlbmiss_st_exits;
1233		ret = kvm_mips_callbacks->handle_tlb_st_miss(vcpu);
1234		break;
1235
1236	case EXCCODE_TLBL:
1237		kvm_debug("TLB LD fault: cause %#x, PC: %p, BadVaddr: %#lx\n",
1238			  cause, opc, badvaddr);
1239
1240		++vcpu->stat.tlbmiss_ld_exits;
1241		ret = kvm_mips_callbacks->handle_tlb_ld_miss(vcpu);
1242		break;
1243
1244	case EXCCODE_ADES:
1245		++vcpu->stat.addrerr_st_exits;
1246		ret = kvm_mips_callbacks->handle_addr_err_st(vcpu);
1247		break;
1248
1249	case EXCCODE_ADEL:
1250		++vcpu->stat.addrerr_ld_exits;
1251		ret = kvm_mips_callbacks->handle_addr_err_ld(vcpu);
1252		break;
1253
1254	case EXCCODE_SYS:
1255		++vcpu->stat.syscall_exits;
1256		ret = kvm_mips_callbacks->handle_syscall(vcpu);
1257		break;
1258
1259	case EXCCODE_RI:
1260		++vcpu->stat.resvd_inst_exits;
1261		ret = kvm_mips_callbacks->handle_res_inst(vcpu);
1262		break;
1263
1264	case EXCCODE_BP:
1265		++vcpu->stat.break_inst_exits;
1266		ret = kvm_mips_callbacks->handle_break(vcpu);
1267		break;
1268
1269	case EXCCODE_TR:
1270		++vcpu->stat.trap_inst_exits;
1271		ret = kvm_mips_callbacks->handle_trap(vcpu);
1272		break;
1273
1274	case EXCCODE_MSAFPE:
1275		++vcpu->stat.msa_fpe_exits;
1276		ret = kvm_mips_callbacks->handle_msa_fpe(vcpu);
1277		break;
1278
1279	case EXCCODE_FPE:
1280		++vcpu->stat.fpe_exits;
1281		ret = kvm_mips_callbacks->handle_fpe(vcpu);
1282		break;
1283
1284	case EXCCODE_MSADIS:
1285		++vcpu->stat.msa_disabled_exits;
1286		ret = kvm_mips_callbacks->handle_msa_disabled(vcpu);
1287		break;
1288
1289	case EXCCODE_GE:
1290		/* defer exit accounting to handler */
1291		ret = kvm_mips_callbacks->handle_guest_exit(vcpu);
1292		break;
1293
1294	default:
1295		if (cause & CAUSEF_BD)
1296			opc += 1;
1297		inst = 0;
1298		kvm_get_badinstr(opc, vcpu, &inst);
1299		kvm_err("Exception Code: %d, not yet handled, @ PC: %p, inst: 0x%08x  BadVaddr: %#lx Status: %#x\n",
1300			exccode, opc, inst, badvaddr,
1301			kvm_read_c0_guest_status(&vcpu->arch.cop0));
1302		kvm_arch_vcpu_dump_regs(vcpu);
1303		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1304		ret = RESUME_HOST;
1305		break;
1306
1307	}
1308
1309	local_irq_disable();
1310
1311	if (ret == RESUME_GUEST)
1312		kvm_vz_acquire_htimer(vcpu);
1313
1314	if (er == EMULATE_DONE && !(ret & RESUME_HOST))
1315		kvm_mips_deliver_interrupts(vcpu, cause);
1316
1317	if (!(ret & RESUME_HOST)) {
1318		/* Only check for signals if not already exiting to userspace */
1319		if (signal_pending(current)) {
1320			run->exit_reason = KVM_EXIT_INTR;
1321			ret = (-EINTR << 2) | RESUME_HOST;
1322			++vcpu->stat.signal_exits;
1323			trace_kvm_exit(vcpu, KVM_TRACE_EXIT_SIGNAL);
1324		}
1325	}
1326
1327	if (ret == RESUME_GUEST) {
1328		trace_kvm_reenter(vcpu);
1329
1330		/*
1331		 * Make sure the read of VCPU requests in vcpu_reenter()
1332		 * callback is not reordered ahead of the write to vcpu->mode,
1333		 * or we could miss a TLB flush request while the requester sees
1334		 * the VCPU as outside of guest mode and not needing an IPI.
1335		 */
1336		smp_store_mb(vcpu->mode, IN_GUEST_MODE);
1337
1338		kvm_mips_callbacks->vcpu_reenter(vcpu);
1339
1340		/*
1341		 * If FPU / MSA are enabled (i.e. the guest's FPU / MSA context
1342		 * is live), restore FCR31 / MSACSR.
1343		 *
1344		 * This should be before returning to the guest exception
1345		 * vector, as it may well cause an [MSA] FP exception if there
1346		 * are pending exception bits unmasked. (see
1347		 * kvm_mips_csr_die_notifier() for how that is handled).
1348		 */
1349		if (kvm_mips_guest_has_fpu(&vcpu->arch) &&
1350		    read_c0_status() & ST0_CU1)
1351			__kvm_restore_fcsr(&vcpu->arch);
1352
1353		if (kvm_mips_guest_has_msa(&vcpu->arch) &&
1354		    read_c0_config5() & MIPS_CONF5_MSAEN)
1355			__kvm_restore_msacsr(&vcpu->arch);
1356	}
1357	return ret;
1358}
1359
1360int noinstr kvm_mips_handle_exit(struct kvm_vcpu *vcpu)
1361{
1362	int ret;
1363
1364	guest_state_exit_irqoff();
1365	ret = __kvm_mips_handle_exit(vcpu);
1366	guest_state_enter_irqoff();
1367
1368	return ret;
1369}
1370
1371/* Enable FPU for guest and restore context */
1372void kvm_own_fpu(struct kvm_vcpu *vcpu)
1373{
1374	struct mips_coproc *cop0 = &vcpu->arch.cop0;
1375	unsigned int sr, cfg5;
1376
1377	preempt_disable();
1378
1379	sr = kvm_read_c0_guest_status(cop0);
1380
1381	/*
1382	 * If MSA state is already live, it is undefined how it interacts with
1383	 * FR=0 FPU state, and we don't want to hit reserved instruction
1384	 * exceptions trying to save the MSA state later when CU=1 && FR=1, so
1385	 * play it safe and save it first.
1386	 */
1387	if (cpu_has_msa && sr & ST0_CU1 && !(sr & ST0_FR) &&
1388	    vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA)
1389		kvm_lose_fpu(vcpu);
1390
1391	/*
1392	 * Enable FPU for guest
1393	 * We set FR and FRE according to guest context
1394	 */
1395	change_c0_status(ST0_CU1 | ST0_FR, sr);
1396	if (cpu_has_fre) {
1397		cfg5 = kvm_read_c0_guest_config5(cop0);
1398		change_c0_config5(MIPS_CONF5_FRE, cfg5);
1399	}
1400	enable_fpu_hazard();
1401
1402	/* If guest FPU state not active, restore it now */
1403	if (!(vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU)) {
1404		__kvm_restore_fpu(&vcpu->arch);
1405		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1406		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_FPU);
1407	} else {
1408		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_FPU);
1409	}
1410
1411	preempt_enable();
1412}
1413
1414#ifdef CONFIG_CPU_HAS_MSA
1415/* Enable MSA for guest and restore context */
1416void kvm_own_msa(struct kvm_vcpu *vcpu)
1417{
1418	struct mips_coproc *cop0 = &vcpu->arch.cop0;
1419	unsigned int sr, cfg5;
1420
1421	preempt_disable();
1422
1423	/*
1424	 * Enable FPU if enabled in guest, since we're restoring FPU context
1425	 * anyway. We set FR and FRE according to guest context.
1426	 */
1427	if (kvm_mips_guest_has_fpu(&vcpu->arch)) {
1428		sr = kvm_read_c0_guest_status(cop0);
1429
1430		/*
1431		 * If FR=0 FPU state is already live, it is undefined how it
1432		 * interacts with MSA state, so play it safe and save it first.
1433		 */
1434		if (!(sr & ST0_FR) &&
1435		    (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU |
1436				KVM_MIPS_AUX_MSA)) == KVM_MIPS_AUX_FPU)
1437			kvm_lose_fpu(vcpu);
1438
1439		change_c0_status(ST0_CU1 | ST0_FR, sr);
1440		if (sr & ST0_CU1 && cpu_has_fre) {
1441			cfg5 = kvm_read_c0_guest_config5(cop0);
1442			change_c0_config5(MIPS_CONF5_FRE, cfg5);
1443		}
1444	}
1445
1446	/* Enable MSA for guest */
1447	set_c0_config5(MIPS_CONF5_MSAEN);
1448	enable_fpu_hazard();
1449
1450	switch (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA)) {
1451	case KVM_MIPS_AUX_FPU:
1452		/*
1453		 * Guest FPU state already loaded, only restore upper MSA state
1454		 */
1455		__kvm_restore_msa_upper(&vcpu->arch);
1456		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1457		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_MSA);
1458		break;
1459	case 0:
1460		/* Neither FPU or MSA already active, restore full MSA state */
1461		__kvm_restore_msa(&vcpu->arch);
1462		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1463		if (kvm_mips_guest_has_fpu(&vcpu->arch))
1464			vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1465		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE,
1466			      KVM_TRACE_AUX_FPU_MSA);
1467		break;
1468	default:
1469		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_MSA);
1470		break;
1471	}
1472
1473	preempt_enable();
1474}
1475#endif
1476
1477/* Drop FPU & MSA without saving it */
1478void kvm_drop_fpu(struct kvm_vcpu *vcpu)
1479{
1480	preempt_disable();
1481	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1482		disable_msa();
1483		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_MSA);
1484		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_MSA;
1485	}
1486	if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1487		clear_c0_status(ST0_CU1 | ST0_FR);
1488		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_FPU);
1489		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1490	}
1491	preempt_enable();
1492}
1493
1494/* Save and disable FPU & MSA */
1495void kvm_lose_fpu(struct kvm_vcpu *vcpu)
1496{
1497	/*
1498	 * With T&E, FPU & MSA get disabled in root context (hardware) when it
1499	 * is disabled in guest context (software), but the register state in
1500	 * the hardware may still be in use.
1501	 * This is why we explicitly re-enable the hardware before saving.
1502	 */
1503
1504	preempt_disable();
1505	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1506		__kvm_save_msa(&vcpu->arch);
1507		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU_MSA);
1508
1509		/* Disable MSA & FPU */
1510		disable_msa();
1511		if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1512			clear_c0_status(ST0_CU1 | ST0_FR);
1513			disable_fpu_hazard();
1514		}
1515		vcpu->arch.aux_inuse &= ~(KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA);
1516	} else if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1517		__kvm_save_fpu(&vcpu->arch);
1518		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1519		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU);
1520
1521		/* Disable FPU */
1522		clear_c0_status(ST0_CU1 | ST0_FR);
1523		disable_fpu_hazard();
1524	}
1525	preempt_enable();
1526}
1527
1528/*
1529 * Step over a specific ctc1 to FCSR and a specific ctcmsa to MSACSR which are
1530 * used to restore guest FCSR/MSACSR state and may trigger a "harmless" FP/MSAFP
1531 * exception if cause bits are set in the value being written.
1532 */
1533static int kvm_mips_csr_die_notify(struct notifier_block *self,
1534				   unsigned long cmd, void *ptr)
1535{
1536	struct die_args *args = (struct die_args *)ptr;
1537	struct pt_regs *regs = args->regs;
1538	unsigned long pc;
1539
1540	/* Only interested in FPE and MSAFPE */
1541	if (cmd != DIE_FP && cmd != DIE_MSAFP)
1542		return NOTIFY_DONE;
1543
1544	/* Return immediately if guest context isn't active */
1545	if (!(current->flags & PF_VCPU))
1546		return NOTIFY_DONE;
1547
1548	/* Should never get here from user mode */
1549	BUG_ON(user_mode(regs));
1550
1551	pc = instruction_pointer(regs);
1552	switch (cmd) {
1553	case DIE_FP:
1554		/* match 2nd instruction in __kvm_restore_fcsr */
1555		if (pc != (unsigned long)&__kvm_restore_fcsr + 4)
1556			return NOTIFY_DONE;
1557		break;
1558	case DIE_MSAFP:
1559		/* match 2nd/3rd instruction in __kvm_restore_msacsr */
1560		if (!cpu_has_msa ||
1561		    pc < (unsigned long)&__kvm_restore_msacsr + 4 ||
1562		    pc > (unsigned long)&__kvm_restore_msacsr + 8)
1563			return NOTIFY_DONE;
1564		break;
1565	}
1566
1567	/* Move PC forward a little and continue executing */
1568	instruction_pointer(regs) += 4;
1569
1570	return NOTIFY_STOP;
1571}
1572
1573static struct notifier_block kvm_mips_csr_die_notifier = {
1574	.notifier_call = kvm_mips_csr_die_notify,
1575};
1576
1577static u32 kvm_default_priority_to_irq[MIPS_EXC_MAX] = {
1578	[MIPS_EXC_INT_TIMER] = C_IRQ5,
1579	[MIPS_EXC_INT_IO_1]  = C_IRQ0,
1580	[MIPS_EXC_INT_IPI_1] = C_IRQ1,
1581	[MIPS_EXC_INT_IPI_2] = C_IRQ2,
1582};
1583
1584static u32 kvm_loongson3_priority_to_irq[MIPS_EXC_MAX] = {
1585	[MIPS_EXC_INT_TIMER] = C_IRQ5,
1586	[MIPS_EXC_INT_IO_1]  = C_IRQ0,
1587	[MIPS_EXC_INT_IO_2]  = C_IRQ1,
1588	[MIPS_EXC_INT_IPI_1] = C_IRQ4,
1589};
1590
1591u32 *kvm_priority_to_irq = kvm_default_priority_to_irq;
1592
1593u32 kvm_irq_to_priority(u32 irq)
1594{
1595	int i;
1596
1597	for (i = MIPS_EXC_INT_TIMER; i < MIPS_EXC_MAX; i++) {
1598		if (kvm_priority_to_irq[i] == (1 << (irq + 8)))
1599			return i;
1600	}
1601
1602	return MIPS_EXC_MAX;
1603}
1604
1605static int __init kvm_mips_init(void)
1606{
1607	int ret;
1608
1609	if (cpu_has_mmid) {
1610		pr_warn("KVM does not yet support MMIDs. KVM Disabled\n");
1611		return -EOPNOTSUPP;
1612	}
1613
1614	ret = kvm_mips_entry_setup();
1615	if (ret)
1616		return ret;
1617
1618	ret = kvm_mips_emulation_init();
1619	if (ret)
1620		return ret;
1621
1622
1623	if (boot_cpu_type() == CPU_LOONGSON64)
1624		kvm_priority_to_irq = kvm_loongson3_priority_to_irq;
1625
1626	register_die_notifier(&kvm_mips_csr_die_notifier);
1627
1628	ret = kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
1629	if (ret) {
1630		unregister_die_notifier(&kvm_mips_csr_die_notifier);
1631		return ret;
1632	}
1633	return 0;
1634}
1635
1636static void __exit kvm_mips_exit(void)
1637{
1638	kvm_exit();
1639
1640	unregister_die_notifier(&kvm_mips_csr_die_notifier);
1641}
1642
1643module_init(kvm_mips_init);
1644module_exit(kvm_mips_exit);
1645
1646EXPORT_TRACEPOINT_SYMBOL(kvm_exit);
1647