xref: /openbmc/linux/arch/mips/kvm/mips.c (revision 941518d6)
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 
41 const struct _kvm_stats_desc kvm_vm_stats_desc[] = {
42 	KVM_GENERIC_VM_STATS()
43 };
44 
45 const 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 
54 const 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 
87 const 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 
96 bool kvm_trace_guest_mode_change;
97 
98 int kvm_guest_mode_change_trace_reg(void)
99 {
100 	kvm_trace_guest_mode_change = true;
101 	return 0;
102 }
103 
104 void 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  */
113 int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
114 {
115 	return !!(vcpu->arch.pending_exceptions);
116 }
117 
118 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
119 {
120 	return false;
121 }
122 
123 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
124 {
125 	return 1;
126 }
127 
128 int kvm_arch_hardware_enable(void)
129 {
130 	return kvm_mips_callbacks->hardware_enable();
131 }
132 
133 void kvm_arch_hardware_disable(void)
134 {
135 	kvm_mips_callbacks->hardware_disable();
136 }
137 
138 int kvm_arch_hardware_setup(void *opaque)
139 {
140 	return 0;
141 }
142 
143 int kvm_arch_check_processor_compat(void *opaque)
144 {
145 	return 0;
146 }
147 
148 extern void kvm_init_loongson_ipi(struct kvm *kvm);
149 
150 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
151 {
152 	switch (type) {
153 	case KVM_VM_MIPS_AUTO:
154 		break;
155 	case KVM_VM_MIPS_VZ:
156 		break;
157 	default:
158 		/* Unsupported KVM type */
159 		return -EINVAL;
160 	}
161 
162 	/* Allocate page table to map GPA -> RPA */
163 	kvm->arch.gpa_mm.pgd = kvm_pgd_alloc();
164 	if (!kvm->arch.gpa_mm.pgd)
165 		return -ENOMEM;
166 
167 #ifdef CONFIG_CPU_LOONGSON64
168 	kvm_init_loongson_ipi(kvm);
169 #endif
170 
171 	return 0;
172 }
173 
174 static void kvm_mips_free_gpa_pt(struct kvm *kvm)
175 {
176 	/* It should always be safe to remove after flushing the whole range */
177 	WARN_ON(!kvm_mips_flush_gpa_pt(kvm, 0, ~0));
178 	pgd_free(NULL, kvm->arch.gpa_mm.pgd);
179 }
180 
181 void kvm_arch_destroy_vm(struct kvm *kvm)
182 {
183 	kvm_destroy_vcpus(kvm);
184 	kvm_mips_free_gpa_pt(kvm);
185 }
186 
187 long kvm_arch_dev_ioctl(struct file *filp, unsigned int ioctl,
188 			unsigned long arg)
189 {
190 	return -ENOIOCTLCMD;
191 }
192 
193 void kvm_arch_flush_shadow_all(struct kvm *kvm)
194 {
195 	/* Flush whole GPA */
196 	kvm_mips_flush_gpa_pt(kvm, 0, ~0);
197 	kvm_flush_remote_tlbs(kvm);
198 }
199 
200 void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
201 				   struct kvm_memory_slot *slot)
202 {
203 	/*
204 	 * The slot has been made invalid (ready for moving or deletion), so we
205 	 * need to ensure that it can no longer be accessed by any guest VCPUs.
206 	 */
207 
208 	spin_lock(&kvm->mmu_lock);
209 	/* Flush slot from GPA */
210 	kvm_mips_flush_gpa_pt(kvm, slot->base_gfn,
211 			      slot->base_gfn + slot->npages - 1);
212 	kvm_arch_flush_remote_tlbs_memslot(kvm, slot);
213 	spin_unlock(&kvm->mmu_lock);
214 }
215 
216 int kvm_arch_prepare_memory_region(struct kvm *kvm,
217 				   const struct kvm_memory_slot *old,
218 				   struct kvm_memory_slot *new,
219 				   enum kvm_mr_change change)
220 {
221 	return 0;
222 }
223 
224 void kvm_arch_commit_memory_region(struct kvm *kvm,
225 				   struct kvm_memory_slot *old,
226 				   const struct kvm_memory_slot *new,
227 				   enum kvm_mr_change change)
228 {
229 	int needs_flush;
230 
231 	/*
232 	 * If dirty page logging is enabled, write protect all pages in the slot
233 	 * ready for dirty logging.
234 	 *
235 	 * There is no need to do this in any of the following cases:
236 	 * CREATE:	No dirty mappings will already exist.
237 	 * MOVE/DELETE:	The old mappings will already have been cleaned up by
238 	 *		kvm_arch_flush_shadow_memslot()
239 	 */
240 	if (change == KVM_MR_FLAGS_ONLY &&
241 	    (!(old->flags & KVM_MEM_LOG_DIRTY_PAGES) &&
242 	     new->flags & KVM_MEM_LOG_DIRTY_PAGES)) {
243 		spin_lock(&kvm->mmu_lock);
244 		/* Write protect GPA page table entries */
245 		needs_flush = kvm_mips_mkclean_gpa_pt(kvm, new->base_gfn,
246 					new->base_gfn + new->npages - 1);
247 		if (needs_flush)
248 			kvm_arch_flush_remote_tlbs_memslot(kvm, new);
249 		spin_unlock(&kvm->mmu_lock);
250 	}
251 }
252 
253 static inline void dump_handler(const char *symbol, void *start, void *end)
254 {
255 	u32 *p;
256 
257 	pr_debug("LEAF(%s)\n", symbol);
258 
259 	pr_debug("\t.set push\n");
260 	pr_debug("\t.set noreorder\n");
261 
262 	for (p = start; p < (u32 *)end; ++p)
263 		pr_debug("\t.word\t0x%08x\t\t# %p\n", *p, p);
264 
265 	pr_debug("\t.set\tpop\n");
266 
267 	pr_debug("\tEND(%s)\n", symbol);
268 }
269 
270 /* low level hrtimer wake routine */
271 static enum hrtimer_restart kvm_mips_comparecount_wakeup(struct hrtimer *timer)
272 {
273 	struct kvm_vcpu *vcpu;
274 
275 	vcpu = container_of(timer, struct kvm_vcpu, arch.comparecount_timer);
276 
277 	kvm_mips_callbacks->queue_timer_int(vcpu);
278 
279 	vcpu->arch.wait = 0;
280 	rcuwait_wake_up(&vcpu->wait);
281 
282 	return kvm_mips_count_timeout(vcpu);
283 }
284 
285 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
286 {
287 	return 0;
288 }
289 
290 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
291 {
292 	int err, size;
293 	void *gebase, *p, *handler, *refill_start, *refill_end;
294 	int i;
295 
296 	kvm_debug("kvm @ %p: create cpu %d at %p\n",
297 		  vcpu->kvm, vcpu->vcpu_id, vcpu);
298 
299 	err = kvm_mips_callbacks->vcpu_init(vcpu);
300 	if (err)
301 		return err;
302 
303 	hrtimer_init(&vcpu->arch.comparecount_timer, CLOCK_MONOTONIC,
304 		     HRTIMER_MODE_REL);
305 	vcpu->arch.comparecount_timer.function = kvm_mips_comparecount_wakeup;
306 
307 	/*
308 	 * Allocate space for host mode exception handlers that handle
309 	 * guest mode exits
310 	 */
311 	if (cpu_has_veic || cpu_has_vint)
312 		size = 0x200 + VECTORSPACING * 64;
313 	else
314 		size = 0x4000;
315 
316 	gebase = kzalloc(ALIGN(size, PAGE_SIZE), GFP_KERNEL);
317 
318 	if (!gebase) {
319 		err = -ENOMEM;
320 		goto out_uninit_vcpu;
321 	}
322 	kvm_debug("Allocated %d bytes for KVM Exception Handlers @ %p\n",
323 		  ALIGN(size, PAGE_SIZE), gebase);
324 
325 	/*
326 	 * Check new ebase actually fits in CP0_EBase. The lack of a write gate
327 	 * limits us to the low 512MB of physical address space. If the memory
328 	 * we allocate is out of range, just give up now.
329 	 */
330 	if (!cpu_has_ebase_wg && virt_to_phys(gebase) >= 0x20000000) {
331 		kvm_err("CP0_EBase.WG required for guest exception base %pK\n",
332 			gebase);
333 		err = -ENOMEM;
334 		goto out_free_gebase;
335 	}
336 
337 	/* Save new ebase */
338 	vcpu->arch.guest_ebase = gebase;
339 
340 	/* Build guest exception vectors dynamically in unmapped memory */
341 	handler = gebase + 0x2000;
342 
343 	/* TLB refill (or XTLB refill on 64-bit VZ where KX=1) */
344 	refill_start = gebase;
345 	if (IS_ENABLED(CONFIG_64BIT))
346 		refill_start += 0x080;
347 	refill_end = kvm_mips_build_tlb_refill_exception(refill_start, handler);
348 
349 	/* General Exception Entry point */
350 	kvm_mips_build_exception(gebase + 0x180, handler);
351 
352 	/* For vectored interrupts poke the exception code @ all offsets 0-7 */
353 	for (i = 0; i < 8; i++) {
354 		kvm_debug("L1 Vectored handler @ %p\n",
355 			  gebase + 0x200 + (i * VECTORSPACING));
356 		kvm_mips_build_exception(gebase + 0x200 + i * VECTORSPACING,
357 					 handler);
358 	}
359 
360 	/* General exit handler */
361 	p = handler;
362 	p = kvm_mips_build_exit(p);
363 
364 	/* Guest entry routine */
365 	vcpu->arch.vcpu_run = p;
366 	p = kvm_mips_build_vcpu_run(p);
367 
368 	/* Dump the generated code */
369 	pr_debug("#include <asm/asm.h>\n");
370 	pr_debug("#include <asm/regdef.h>\n");
371 	pr_debug("\n");
372 	dump_handler("kvm_vcpu_run", vcpu->arch.vcpu_run, p);
373 	dump_handler("kvm_tlb_refill", refill_start, refill_end);
374 	dump_handler("kvm_gen_exc", gebase + 0x180, gebase + 0x200);
375 	dump_handler("kvm_exit", gebase + 0x2000, vcpu->arch.vcpu_run);
376 
377 	/* Invalidate the icache for these ranges */
378 	flush_icache_range((unsigned long)gebase,
379 			   (unsigned long)gebase + ALIGN(size, PAGE_SIZE));
380 
381 	/* Init */
382 	vcpu->arch.last_sched_cpu = -1;
383 	vcpu->arch.last_exec_cpu = -1;
384 
385 	/* Initial guest state */
386 	err = kvm_mips_callbacks->vcpu_setup(vcpu);
387 	if (err)
388 		goto out_free_gebase;
389 
390 	return 0;
391 
392 out_free_gebase:
393 	kfree(gebase);
394 out_uninit_vcpu:
395 	kvm_mips_callbacks->vcpu_uninit(vcpu);
396 	return err;
397 }
398 
399 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
400 {
401 	hrtimer_cancel(&vcpu->arch.comparecount_timer);
402 
403 	kvm_mips_dump_stats(vcpu);
404 
405 	kvm_mmu_free_memory_caches(vcpu);
406 	kfree(vcpu->arch.guest_ebase);
407 
408 	kvm_mips_callbacks->vcpu_uninit(vcpu);
409 }
410 
411 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
412 					struct kvm_guest_debug *dbg)
413 {
414 	return -ENOIOCTLCMD;
415 }
416 
417 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
418 {
419 	int r = -EINTR;
420 
421 	vcpu_load(vcpu);
422 
423 	kvm_sigset_activate(vcpu);
424 
425 	if (vcpu->mmio_needed) {
426 		if (!vcpu->mmio_is_write)
427 			kvm_mips_complete_mmio_load(vcpu);
428 		vcpu->mmio_needed = 0;
429 	}
430 
431 	if (vcpu->run->immediate_exit)
432 		goto out;
433 
434 	lose_fpu(1);
435 
436 	local_irq_disable();
437 	guest_enter_irqoff();
438 	trace_kvm_enter(vcpu);
439 
440 	/*
441 	 * Make sure the read of VCPU requests in vcpu_run() callback is not
442 	 * reordered ahead of the write to vcpu->mode, or we could miss a TLB
443 	 * flush request while the requester sees the VCPU as outside of guest
444 	 * mode and not needing an IPI.
445 	 */
446 	smp_store_mb(vcpu->mode, IN_GUEST_MODE);
447 
448 	r = kvm_mips_callbacks->vcpu_run(vcpu);
449 
450 	trace_kvm_out(vcpu);
451 	guest_exit_irqoff();
452 	local_irq_enable();
453 
454 out:
455 	kvm_sigset_deactivate(vcpu);
456 
457 	vcpu_put(vcpu);
458 	return r;
459 }
460 
461 int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
462 			     struct kvm_mips_interrupt *irq)
463 {
464 	int intr = (int)irq->irq;
465 	struct kvm_vcpu *dvcpu = NULL;
466 
467 	if (intr == kvm_priority_to_irq[MIPS_EXC_INT_IPI_1] ||
468 	    intr == kvm_priority_to_irq[MIPS_EXC_INT_IPI_2] ||
469 	    intr == (-kvm_priority_to_irq[MIPS_EXC_INT_IPI_1]) ||
470 	    intr == (-kvm_priority_to_irq[MIPS_EXC_INT_IPI_2]))
471 		kvm_debug("%s: CPU: %d, INTR: %d\n", __func__, irq->cpu,
472 			  (int)intr);
473 
474 	if (irq->cpu == -1)
475 		dvcpu = vcpu;
476 	else
477 		dvcpu = kvm_get_vcpu(vcpu->kvm, irq->cpu);
478 
479 	if (intr == 2 || intr == 3 || intr == 4 || intr == 6) {
480 		kvm_mips_callbacks->queue_io_int(dvcpu, irq);
481 
482 	} else if (intr == -2 || intr == -3 || intr == -4 || intr == -6) {
483 		kvm_mips_callbacks->dequeue_io_int(dvcpu, irq);
484 	} else {
485 		kvm_err("%s: invalid interrupt ioctl (%d:%d)\n", __func__,
486 			irq->cpu, irq->irq);
487 		return -EINVAL;
488 	}
489 
490 	dvcpu->arch.wait = 0;
491 
492 	rcuwait_wake_up(&dvcpu->wait);
493 
494 	return 0;
495 }
496 
497 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
498 				    struct kvm_mp_state *mp_state)
499 {
500 	return -ENOIOCTLCMD;
501 }
502 
503 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
504 				    struct kvm_mp_state *mp_state)
505 {
506 	return -ENOIOCTLCMD;
507 }
508 
509 static u64 kvm_mips_get_one_regs[] = {
510 	KVM_REG_MIPS_R0,
511 	KVM_REG_MIPS_R1,
512 	KVM_REG_MIPS_R2,
513 	KVM_REG_MIPS_R3,
514 	KVM_REG_MIPS_R4,
515 	KVM_REG_MIPS_R5,
516 	KVM_REG_MIPS_R6,
517 	KVM_REG_MIPS_R7,
518 	KVM_REG_MIPS_R8,
519 	KVM_REG_MIPS_R9,
520 	KVM_REG_MIPS_R10,
521 	KVM_REG_MIPS_R11,
522 	KVM_REG_MIPS_R12,
523 	KVM_REG_MIPS_R13,
524 	KVM_REG_MIPS_R14,
525 	KVM_REG_MIPS_R15,
526 	KVM_REG_MIPS_R16,
527 	KVM_REG_MIPS_R17,
528 	KVM_REG_MIPS_R18,
529 	KVM_REG_MIPS_R19,
530 	KVM_REG_MIPS_R20,
531 	KVM_REG_MIPS_R21,
532 	KVM_REG_MIPS_R22,
533 	KVM_REG_MIPS_R23,
534 	KVM_REG_MIPS_R24,
535 	KVM_REG_MIPS_R25,
536 	KVM_REG_MIPS_R26,
537 	KVM_REG_MIPS_R27,
538 	KVM_REG_MIPS_R28,
539 	KVM_REG_MIPS_R29,
540 	KVM_REG_MIPS_R30,
541 	KVM_REG_MIPS_R31,
542 
543 #ifndef CONFIG_CPU_MIPSR6
544 	KVM_REG_MIPS_HI,
545 	KVM_REG_MIPS_LO,
546 #endif
547 	KVM_REG_MIPS_PC,
548 };
549 
550 static u64 kvm_mips_get_one_regs_fpu[] = {
551 	KVM_REG_MIPS_FCR_IR,
552 	KVM_REG_MIPS_FCR_CSR,
553 };
554 
555 static u64 kvm_mips_get_one_regs_msa[] = {
556 	KVM_REG_MIPS_MSA_IR,
557 	KVM_REG_MIPS_MSA_CSR,
558 };
559 
560 static unsigned long kvm_mips_num_regs(struct kvm_vcpu *vcpu)
561 {
562 	unsigned long ret;
563 
564 	ret = ARRAY_SIZE(kvm_mips_get_one_regs);
565 	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
566 		ret += ARRAY_SIZE(kvm_mips_get_one_regs_fpu) + 48;
567 		/* odd doubles */
568 		if (boot_cpu_data.fpu_id & MIPS_FPIR_F64)
569 			ret += 16;
570 	}
571 	if (kvm_mips_guest_can_have_msa(&vcpu->arch))
572 		ret += ARRAY_SIZE(kvm_mips_get_one_regs_msa) + 32;
573 	ret += kvm_mips_callbacks->num_regs(vcpu);
574 
575 	return ret;
576 }
577 
578 static int kvm_mips_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices)
579 {
580 	u64 index;
581 	unsigned int i;
582 
583 	if (copy_to_user(indices, kvm_mips_get_one_regs,
584 			 sizeof(kvm_mips_get_one_regs)))
585 		return -EFAULT;
586 	indices += ARRAY_SIZE(kvm_mips_get_one_regs);
587 
588 	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
589 		if (copy_to_user(indices, kvm_mips_get_one_regs_fpu,
590 				 sizeof(kvm_mips_get_one_regs_fpu)))
591 			return -EFAULT;
592 		indices += ARRAY_SIZE(kvm_mips_get_one_regs_fpu);
593 
594 		for (i = 0; i < 32; ++i) {
595 			index = KVM_REG_MIPS_FPR_32(i);
596 			if (copy_to_user(indices, &index, sizeof(index)))
597 				return -EFAULT;
598 			++indices;
599 
600 			/* skip odd doubles if no F64 */
601 			if (i & 1 && !(boot_cpu_data.fpu_id & MIPS_FPIR_F64))
602 				continue;
603 
604 			index = KVM_REG_MIPS_FPR_64(i);
605 			if (copy_to_user(indices, &index, sizeof(index)))
606 				return -EFAULT;
607 			++indices;
608 		}
609 	}
610 
611 	if (kvm_mips_guest_can_have_msa(&vcpu->arch)) {
612 		if (copy_to_user(indices, kvm_mips_get_one_regs_msa,
613 				 sizeof(kvm_mips_get_one_regs_msa)))
614 			return -EFAULT;
615 		indices += ARRAY_SIZE(kvm_mips_get_one_regs_msa);
616 
617 		for (i = 0; i < 32; ++i) {
618 			index = KVM_REG_MIPS_VEC_128(i);
619 			if (copy_to_user(indices, &index, sizeof(index)))
620 				return -EFAULT;
621 			++indices;
622 		}
623 	}
624 
625 	return kvm_mips_callbacks->copy_reg_indices(vcpu, indices);
626 }
627 
628 static int kvm_mips_get_reg(struct kvm_vcpu *vcpu,
629 			    const struct kvm_one_reg *reg)
630 {
631 	struct mips_coproc *cop0 = vcpu->arch.cop0;
632 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
633 	int ret;
634 	s64 v;
635 	s64 vs[2];
636 	unsigned int idx;
637 
638 	switch (reg->id) {
639 	/* General purpose registers */
640 	case KVM_REG_MIPS_R0 ... KVM_REG_MIPS_R31:
641 		v = (long)vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0];
642 		break;
643 #ifndef CONFIG_CPU_MIPSR6
644 	case KVM_REG_MIPS_HI:
645 		v = (long)vcpu->arch.hi;
646 		break;
647 	case KVM_REG_MIPS_LO:
648 		v = (long)vcpu->arch.lo;
649 		break;
650 #endif
651 	case KVM_REG_MIPS_PC:
652 		v = (long)vcpu->arch.pc;
653 		break;
654 
655 	/* Floating point registers */
656 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
657 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
658 			return -EINVAL;
659 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
660 		/* Odd singles in top of even double when FR=0 */
661 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
662 			v = get_fpr32(&fpu->fpr[idx], 0);
663 		else
664 			v = get_fpr32(&fpu->fpr[idx & ~1], idx & 1);
665 		break;
666 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
667 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
668 			return -EINVAL;
669 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
670 		/* Can't access odd doubles in FR=0 mode */
671 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
672 			return -EINVAL;
673 		v = get_fpr64(&fpu->fpr[idx], 0);
674 		break;
675 	case KVM_REG_MIPS_FCR_IR:
676 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
677 			return -EINVAL;
678 		v = boot_cpu_data.fpu_id;
679 		break;
680 	case KVM_REG_MIPS_FCR_CSR:
681 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
682 			return -EINVAL;
683 		v = fpu->fcr31;
684 		break;
685 
686 	/* MIPS SIMD Architecture (MSA) registers */
687 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
688 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
689 			return -EINVAL;
690 		/* Can't access MSA registers in FR=0 mode */
691 		if (!(kvm_read_c0_guest_status(cop0) & ST0_FR))
692 			return -EINVAL;
693 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
694 #ifdef CONFIG_CPU_LITTLE_ENDIAN
695 		/* least significant byte first */
696 		vs[0] = get_fpr64(&fpu->fpr[idx], 0);
697 		vs[1] = get_fpr64(&fpu->fpr[idx], 1);
698 #else
699 		/* most significant byte first */
700 		vs[0] = get_fpr64(&fpu->fpr[idx], 1);
701 		vs[1] = get_fpr64(&fpu->fpr[idx], 0);
702 #endif
703 		break;
704 	case KVM_REG_MIPS_MSA_IR:
705 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
706 			return -EINVAL;
707 		v = boot_cpu_data.msa_id;
708 		break;
709 	case KVM_REG_MIPS_MSA_CSR:
710 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
711 			return -EINVAL;
712 		v = fpu->msacsr;
713 		break;
714 
715 	/* registers to be handled specially */
716 	default:
717 		ret = kvm_mips_callbacks->get_one_reg(vcpu, reg, &v);
718 		if (ret)
719 			return ret;
720 		break;
721 	}
722 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
723 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
724 
725 		return put_user(v, uaddr64);
726 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
727 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
728 		u32 v32 = (u32)v;
729 
730 		return put_user(v32, uaddr32);
731 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
732 		void __user *uaddr = (void __user *)(long)reg->addr;
733 
734 		return copy_to_user(uaddr, vs, 16) ? -EFAULT : 0;
735 	} else {
736 		return -EINVAL;
737 	}
738 }
739 
740 static int kvm_mips_set_reg(struct kvm_vcpu *vcpu,
741 			    const struct kvm_one_reg *reg)
742 {
743 	struct mips_coproc *cop0 = vcpu->arch.cop0;
744 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
745 	s64 v;
746 	s64 vs[2];
747 	unsigned int idx;
748 
749 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
750 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
751 
752 		if (get_user(v, uaddr64) != 0)
753 			return -EFAULT;
754 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
755 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
756 		s32 v32;
757 
758 		if (get_user(v32, uaddr32) != 0)
759 			return -EFAULT;
760 		v = (s64)v32;
761 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
762 		void __user *uaddr = (void __user *)(long)reg->addr;
763 
764 		return copy_from_user(vs, uaddr, 16) ? -EFAULT : 0;
765 	} else {
766 		return -EINVAL;
767 	}
768 
769 	switch (reg->id) {
770 	/* General purpose registers */
771 	case KVM_REG_MIPS_R0:
772 		/* Silently ignore requests to set $0 */
773 		break;
774 	case KVM_REG_MIPS_R1 ... KVM_REG_MIPS_R31:
775 		vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0] = v;
776 		break;
777 #ifndef CONFIG_CPU_MIPSR6
778 	case KVM_REG_MIPS_HI:
779 		vcpu->arch.hi = v;
780 		break;
781 	case KVM_REG_MIPS_LO:
782 		vcpu->arch.lo = v;
783 		break;
784 #endif
785 	case KVM_REG_MIPS_PC:
786 		vcpu->arch.pc = v;
787 		break;
788 
789 	/* Floating point registers */
790 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
791 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
792 			return -EINVAL;
793 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
794 		/* Odd singles in top of even double when FR=0 */
795 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
796 			set_fpr32(&fpu->fpr[idx], 0, v);
797 		else
798 			set_fpr32(&fpu->fpr[idx & ~1], idx & 1, v);
799 		break;
800 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
801 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
802 			return -EINVAL;
803 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
804 		/* Can't access odd doubles in FR=0 mode */
805 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
806 			return -EINVAL;
807 		set_fpr64(&fpu->fpr[idx], 0, v);
808 		break;
809 	case KVM_REG_MIPS_FCR_IR:
810 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
811 			return -EINVAL;
812 		/* Read-only */
813 		break;
814 	case KVM_REG_MIPS_FCR_CSR:
815 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
816 			return -EINVAL;
817 		fpu->fcr31 = v;
818 		break;
819 
820 	/* MIPS SIMD Architecture (MSA) registers */
821 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
822 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
823 			return -EINVAL;
824 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
825 #ifdef CONFIG_CPU_LITTLE_ENDIAN
826 		/* least significant byte first */
827 		set_fpr64(&fpu->fpr[idx], 0, vs[0]);
828 		set_fpr64(&fpu->fpr[idx], 1, vs[1]);
829 #else
830 		/* most significant byte first */
831 		set_fpr64(&fpu->fpr[idx], 1, vs[0]);
832 		set_fpr64(&fpu->fpr[idx], 0, vs[1]);
833 #endif
834 		break;
835 	case KVM_REG_MIPS_MSA_IR:
836 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
837 			return -EINVAL;
838 		/* Read-only */
839 		break;
840 	case KVM_REG_MIPS_MSA_CSR:
841 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
842 			return -EINVAL;
843 		fpu->msacsr = v;
844 		break;
845 
846 	/* registers to be handled specially */
847 	default:
848 		return kvm_mips_callbacks->set_one_reg(vcpu, reg, v);
849 	}
850 	return 0;
851 }
852 
853 static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
854 				     struct kvm_enable_cap *cap)
855 {
856 	int r = 0;
857 
858 	if (!kvm_vm_ioctl_check_extension(vcpu->kvm, cap->cap))
859 		return -EINVAL;
860 	if (cap->flags)
861 		return -EINVAL;
862 	if (cap->args[0])
863 		return -EINVAL;
864 
865 	switch (cap->cap) {
866 	case KVM_CAP_MIPS_FPU:
867 		vcpu->arch.fpu_enabled = true;
868 		break;
869 	case KVM_CAP_MIPS_MSA:
870 		vcpu->arch.msa_enabled = true;
871 		break;
872 	default:
873 		r = -EINVAL;
874 		break;
875 	}
876 
877 	return r;
878 }
879 
880 long kvm_arch_vcpu_async_ioctl(struct file *filp, unsigned int ioctl,
881 			       unsigned long arg)
882 {
883 	struct kvm_vcpu *vcpu = filp->private_data;
884 	void __user *argp = (void __user *)arg;
885 
886 	if (ioctl == KVM_INTERRUPT) {
887 		struct kvm_mips_interrupt irq;
888 
889 		if (copy_from_user(&irq, argp, sizeof(irq)))
890 			return -EFAULT;
891 		kvm_debug("[%d] %s: irq: %d\n", vcpu->vcpu_id, __func__,
892 			  irq.irq);
893 
894 		return kvm_vcpu_ioctl_interrupt(vcpu, &irq);
895 	}
896 
897 	return -ENOIOCTLCMD;
898 }
899 
900 long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl,
901 			 unsigned long arg)
902 {
903 	struct kvm_vcpu *vcpu = filp->private_data;
904 	void __user *argp = (void __user *)arg;
905 	long r;
906 
907 	vcpu_load(vcpu);
908 
909 	switch (ioctl) {
910 	case KVM_SET_ONE_REG:
911 	case KVM_GET_ONE_REG: {
912 		struct kvm_one_reg reg;
913 
914 		r = -EFAULT;
915 		if (copy_from_user(&reg, argp, sizeof(reg)))
916 			break;
917 		if (ioctl == KVM_SET_ONE_REG)
918 			r = kvm_mips_set_reg(vcpu, &reg);
919 		else
920 			r = kvm_mips_get_reg(vcpu, &reg);
921 		break;
922 	}
923 	case KVM_GET_REG_LIST: {
924 		struct kvm_reg_list __user *user_list = argp;
925 		struct kvm_reg_list reg_list;
926 		unsigned n;
927 
928 		r = -EFAULT;
929 		if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
930 			break;
931 		n = reg_list.n;
932 		reg_list.n = kvm_mips_num_regs(vcpu);
933 		if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
934 			break;
935 		r = -E2BIG;
936 		if (n < reg_list.n)
937 			break;
938 		r = kvm_mips_copy_reg_indices(vcpu, user_list->reg);
939 		break;
940 	}
941 	case KVM_ENABLE_CAP: {
942 		struct kvm_enable_cap cap;
943 
944 		r = -EFAULT;
945 		if (copy_from_user(&cap, argp, sizeof(cap)))
946 			break;
947 		r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
948 		break;
949 	}
950 	default:
951 		r = -ENOIOCTLCMD;
952 	}
953 
954 	vcpu_put(vcpu);
955 	return r;
956 }
957 
958 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
959 {
960 
961 }
962 
963 int kvm_arch_flush_remote_tlb(struct kvm *kvm)
964 {
965 	kvm_mips_callbacks->prepare_flush_shadow(kvm);
966 	return 1;
967 }
968 
969 void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
970 					const struct kvm_memory_slot *memslot)
971 {
972 	kvm_flush_remote_tlbs(kvm);
973 }
974 
975 long kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
976 {
977 	long r;
978 
979 	switch (ioctl) {
980 	default:
981 		r = -ENOIOCTLCMD;
982 	}
983 
984 	return r;
985 }
986 
987 int kvm_arch_init(void *opaque)
988 {
989 	if (kvm_mips_callbacks) {
990 		kvm_err("kvm: module already exists\n");
991 		return -EEXIST;
992 	}
993 
994 	return kvm_mips_emulation_init(&kvm_mips_callbacks);
995 }
996 
997 void kvm_arch_exit(void)
998 {
999 	kvm_mips_callbacks = NULL;
1000 }
1001 
1002 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
1003 				  struct kvm_sregs *sregs)
1004 {
1005 	return -ENOIOCTLCMD;
1006 }
1007 
1008 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
1009 				  struct kvm_sregs *sregs)
1010 {
1011 	return -ENOIOCTLCMD;
1012 }
1013 
1014 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
1015 {
1016 }
1017 
1018 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1019 {
1020 	return -ENOIOCTLCMD;
1021 }
1022 
1023 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1024 {
1025 	return -ENOIOCTLCMD;
1026 }
1027 
1028 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
1029 {
1030 	return VM_FAULT_SIGBUS;
1031 }
1032 
1033 int 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 
1080 int 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 
1086 int 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 
1117 int 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 
1134 int 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 
1151 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
1152 				  struct kvm_translation *tr)
1153 {
1154 	return 0;
1155 }
1156 
1157 static 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  */
1171 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 
1360 /* Enable FPU for guest and restore context */
1361 void kvm_own_fpu(struct kvm_vcpu *vcpu)
1362 {
1363 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1364 	unsigned int sr, cfg5;
1365 
1366 	preempt_disable();
1367 
1368 	sr = kvm_read_c0_guest_status(cop0);
1369 
1370 	/*
1371 	 * If MSA state is already live, it is undefined how it interacts with
1372 	 * FR=0 FPU state, and we don't want to hit reserved instruction
1373 	 * exceptions trying to save the MSA state later when CU=1 && FR=1, so
1374 	 * play it safe and save it first.
1375 	 */
1376 	if (cpu_has_msa && sr & ST0_CU1 && !(sr & ST0_FR) &&
1377 	    vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA)
1378 		kvm_lose_fpu(vcpu);
1379 
1380 	/*
1381 	 * Enable FPU for guest
1382 	 * We set FR and FRE according to guest context
1383 	 */
1384 	change_c0_status(ST0_CU1 | ST0_FR, sr);
1385 	if (cpu_has_fre) {
1386 		cfg5 = kvm_read_c0_guest_config5(cop0);
1387 		change_c0_config5(MIPS_CONF5_FRE, cfg5);
1388 	}
1389 	enable_fpu_hazard();
1390 
1391 	/* If guest FPU state not active, restore it now */
1392 	if (!(vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU)) {
1393 		__kvm_restore_fpu(&vcpu->arch);
1394 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1395 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_FPU);
1396 	} else {
1397 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_FPU);
1398 	}
1399 
1400 	preempt_enable();
1401 }
1402 
1403 #ifdef CONFIG_CPU_HAS_MSA
1404 /* Enable MSA for guest and restore context */
1405 void kvm_own_msa(struct kvm_vcpu *vcpu)
1406 {
1407 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1408 	unsigned int sr, cfg5;
1409 
1410 	preempt_disable();
1411 
1412 	/*
1413 	 * Enable FPU if enabled in guest, since we're restoring FPU context
1414 	 * anyway. We set FR and FRE according to guest context.
1415 	 */
1416 	if (kvm_mips_guest_has_fpu(&vcpu->arch)) {
1417 		sr = kvm_read_c0_guest_status(cop0);
1418 
1419 		/*
1420 		 * If FR=0 FPU state is already live, it is undefined how it
1421 		 * interacts with MSA state, so play it safe and save it first.
1422 		 */
1423 		if (!(sr & ST0_FR) &&
1424 		    (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU |
1425 				KVM_MIPS_AUX_MSA)) == KVM_MIPS_AUX_FPU)
1426 			kvm_lose_fpu(vcpu);
1427 
1428 		change_c0_status(ST0_CU1 | ST0_FR, sr);
1429 		if (sr & ST0_CU1 && cpu_has_fre) {
1430 			cfg5 = kvm_read_c0_guest_config5(cop0);
1431 			change_c0_config5(MIPS_CONF5_FRE, cfg5);
1432 		}
1433 	}
1434 
1435 	/* Enable MSA for guest */
1436 	set_c0_config5(MIPS_CONF5_MSAEN);
1437 	enable_fpu_hazard();
1438 
1439 	switch (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA)) {
1440 	case KVM_MIPS_AUX_FPU:
1441 		/*
1442 		 * Guest FPU state already loaded, only restore upper MSA state
1443 		 */
1444 		__kvm_restore_msa_upper(&vcpu->arch);
1445 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1446 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_MSA);
1447 		break;
1448 	case 0:
1449 		/* Neither FPU or MSA already active, restore full MSA state */
1450 		__kvm_restore_msa(&vcpu->arch);
1451 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1452 		if (kvm_mips_guest_has_fpu(&vcpu->arch))
1453 			vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1454 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE,
1455 			      KVM_TRACE_AUX_FPU_MSA);
1456 		break;
1457 	default:
1458 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_MSA);
1459 		break;
1460 	}
1461 
1462 	preempt_enable();
1463 }
1464 #endif
1465 
1466 /* Drop FPU & MSA without saving it */
1467 void kvm_drop_fpu(struct kvm_vcpu *vcpu)
1468 {
1469 	preempt_disable();
1470 	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1471 		disable_msa();
1472 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_MSA);
1473 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_MSA;
1474 	}
1475 	if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1476 		clear_c0_status(ST0_CU1 | ST0_FR);
1477 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_FPU);
1478 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1479 	}
1480 	preempt_enable();
1481 }
1482 
1483 /* Save and disable FPU & MSA */
1484 void kvm_lose_fpu(struct kvm_vcpu *vcpu)
1485 {
1486 	/*
1487 	 * With T&E, FPU & MSA get disabled in root context (hardware) when it
1488 	 * is disabled in guest context (software), but the register state in
1489 	 * the hardware may still be in use.
1490 	 * This is why we explicitly re-enable the hardware before saving.
1491 	 */
1492 
1493 	preempt_disable();
1494 	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1495 		__kvm_save_msa(&vcpu->arch);
1496 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU_MSA);
1497 
1498 		/* Disable MSA & FPU */
1499 		disable_msa();
1500 		if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1501 			clear_c0_status(ST0_CU1 | ST0_FR);
1502 			disable_fpu_hazard();
1503 		}
1504 		vcpu->arch.aux_inuse &= ~(KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA);
1505 	} else if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1506 		__kvm_save_fpu(&vcpu->arch);
1507 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1508 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU);
1509 
1510 		/* Disable FPU */
1511 		clear_c0_status(ST0_CU1 | ST0_FR);
1512 		disable_fpu_hazard();
1513 	}
1514 	preempt_enable();
1515 }
1516 
1517 /*
1518  * Step over a specific ctc1 to FCSR and a specific ctcmsa to MSACSR which are
1519  * used to restore guest FCSR/MSACSR state and may trigger a "harmless" FP/MSAFP
1520  * exception if cause bits are set in the value being written.
1521  */
1522 static int kvm_mips_csr_die_notify(struct notifier_block *self,
1523 				   unsigned long cmd, void *ptr)
1524 {
1525 	struct die_args *args = (struct die_args *)ptr;
1526 	struct pt_regs *regs = args->regs;
1527 	unsigned long pc;
1528 
1529 	/* Only interested in FPE and MSAFPE */
1530 	if (cmd != DIE_FP && cmd != DIE_MSAFP)
1531 		return NOTIFY_DONE;
1532 
1533 	/* Return immediately if guest context isn't active */
1534 	if (!(current->flags & PF_VCPU))
1535 		return NOTIFY_DONE;
1536 
1537 	/* Should never get here from user mode */
1538 	BUG_ON(user_mode(regs));
1539 
1540 	pc = instruction_pointer(regs);
1541 	switch (cmd) {
1542 	case DIE_FP:
1543 		/* match 2nd instruction in __kvm_restore_fcsr */
1544 		if (pc != (unsigned long)&__kvm_restore_fcsr + 4)
1545 			return NOTIFY_DONE;
1546 		break;
1547 	case DIE_MSAFP:
1548 		/* match 2nd/3rd instruction in __kvm_restore_msacsr */
1549 		if (!cpu_has_msa ||
1550 		    pc < (unsigned long)&__kvm_restore_msacsr + 4 ||
1551 		    pc > (unsigned long)&__kvm_restore_msacsr + 8)
1552 			return NOTIFY_DONE;
1553 		break;
1554 	}
1555 
1556 	/* Move PC forward a little and continue executing */
1557 	instruction_pointer(regs) += 4;
1558 
1559 	return NOTIFY_STOP;
1560 }
1561 
1562 static struct notifier_block kvm_mips_csr_die_notifier = {
1563 	.notifier_call = kvm_mips_csr_die_notify,
1564 };
1565 
1566 static u32 kvm_default_priority_to_irq[MIPS_EXC_MAX] = {
1567 	[MIPS_EXC_INT_TIMER] = C_IRQ5,
1568 	[MIPS_EXC_INT_IO_1]  = C_IRQ0,
1569 	[MIPS_EXC_INT_IPI_1] = C_IRQ1,
1570 	[MIPS_EXC_INT_IPI_2] = C_IRQ2,
1571 };
1572 
1573 static u32 kvm_loongson3_priority_to_irq[MIPS_EXC_MAX] = {
1574 	[MIPS_EXC_INT_TIMER] = C_IRQ5,
1575 	[MIPS_EXC_INT_IO_1]  = C_IRQ0,
1576 	[MIPS_EXC_INT_IO_2]  = C_IRQ1,
1577 	[MIPS_EXC_INT_IPI_1] = C_IRQ4,
1578 };
1579 
1580 u32 *kvm_priority_to_irq = kvm_default_priority_to_irq;
1581 
1582 u32 kvm_irq_to_priority(u32 irq)
1583 {
1584 	int i;
1585 
1586 	for (i = MIPS_EXC_INT_TIMER; i < MIPS_EXC_MAX; i++) {
1587 		if (kvm_priority_to_irq[i] == (1 << (irq + 8)))
1588 			return i;
1589 	}
1590 
1591 	return MIPS_EXC_MAX;
1592 }
1593 
1594 static int __init kvm_mips_init(void)
1595 {
1596 	int ret;
1597 
1598 	if (cpu_has_mmid) {
1599 		pr_warn("KVM does not yet support MMIDs. KVM Disabled\n");
1600 		return -EOPNOTSUPP;
1601 	}
1602 
1603 	ret = kvm_mips_entry_setup();
1604 	if (ret)
1605 		return ret;
1606 
1607 	ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
1608 
1609 	if (ret)
1610 		return ret;
1611 
1612 	if (boot_cpu_type() == CPU_LOONGSON64)
1613 		kvm_priority_to_irq = kvm_loongson3_priority_to_irq;
1614 
1615 	register_die_notifier(&kvm_mips_csr_die_notifier);
1616 
1617 	return 0;
1618 }
1619 
1620 static void __exit kvm_mips_exit(void)
1621 {
1622 	kvm_exit();
1623 
1624 	unregister_die_notifier(&kvm_mips_csr_die_notifier);
1625 }
1626 
1627 module_init(kvm_mips_init);
1628 module_exit(kvm_mips_exit);
1629 
1630 EXPORT_TRACEPOINT_SYMBOL(kvm_exit);
1631