xref: /openbmc/linux/arch/mips/kvm/mips.c (revision a578a0a9e3526483ad1904fac019d95e7089fb34)
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_check_processor_compat(void *opaque)
139 {
140 	return 0;
141 }
142 
143 extern void kvm_init_loongson_ipi(struct kvm *kvm);
144 
145 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
146 {
147 	switch (type) {
148 	case KVM_VM_MIPS_AUTO:
149 		break;
150 	case KVM_VM_MIPS_VZ:
151 		break;
152 	default:
153 		/* Unsupported KVM type */
154 		return -EINVAL;
155 	}
156 
157 	/* Allocate page table to map GPA -> RPA */
158 	kvm->arch.gpa_mm.pgd = kvm_pgd_alloc();
159 	if (!kvm->arch.gpa_mm.pgd)
160 		return -ENOMEM;
161 
162 #ifdef CONFIG_CPU_LOONGSON64
163 	kvm_init_loongson_ipi(kvm);
164 #endif
165 
166 	return 0;
167 }
168 
169 static void kvm_mips_free_gpa_pt(struct kvm *kvm)
170 {
171 	/* It should always be safe to remove after flushing the whole range */
172 	WARN_ON(!kvm_mips_flush_gpa_pt(kvm, 0, ~0));
173 	pgd_free(NULL, kvm->arch.gpa_mm.pgd);
174 }
175 
176 void kvm_arch_destroy_vm(struct kvm *kvm)
177 {
178 	kvm_destroy_vcpus(kvm);
179 	kvm_mips_free_gpa_pt(kvm);
180 }
181 
182 long kvm_arch_dev_ioctl(struct file *filp, unsigned int ioctl,
183 			unsigned long arg)
184 {
185 	return -ENOIOCTLCMD;
186 }
187 
188 void kvm_arch_flush_shadow_all(struct kvm *kvm)
189 {
190 	/* Flush whole GPA */
191 	kvm_mips_flush_gpa_pt(kvm, 0, ~0);
192 	kvm_flush_remote_tlbs(kvm);
193 }
194 
195 void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
196 				   struct kvm_memory_slot *slot)
197 {
198 	/*
199 	 * The slot has been made invalid (ready for moving or deletion), so we
200 	 * need to ensure that it can no longer be accessed by any guest VCPUs.
201 	 */
202 
203 	spin_lock(&kvm->mmu_lock);
204 	/* Flush slot from GPA */
205 	kvm_mips_flush_gpa_pt(kvm, slot->base_gfn,
206 			      slot->base_gfn + slot->npages - 1);
207 	kvm_arch_flush_remote_tlbs_memslot(kvm, slot);
208 	spin_unlock(&kvm->mmu_lock);
209 }
210 
211 int kvm_arch_prepare_memory_region(struct kvm *kvm,
212 				   const struct kvm_memory_slot *old,
213 				   struct kvm_memory_slot *new,
214 				   enum kvm_mr_change change)
215 {
216 	return 0;
217 }
218 
219 void kvm_arch_commit_memory_region(struct kvm *kvm,
220 				   struct kvm_memory_slot *old,
221 				   const struct kvm_memory_slot *new,
222 				   enum kvm_mr_change change)
223 {
224 	int needs_flush;
225 
226 	/*
227 	 * If dirty page logging is enabled, write protect all pages in the slot
228 	 * ready for dirty logging.
229 	 *
230 	 * There is no need to do this in any of the following cases:
231 	 * CREATE:	No dirty mappings will already exist.
232 	 * MOVE/DELETE:	The old mappings will already have been cleaned up by
233 	 *		kvm_arch_flush_shadow_memslot()
234 	 */
235 	if (change == KVM_MR_FLAGS_ONLY &&
236 	    (!(old->flags & KVM_MEM_LOG_DIRTY_PAGES) &&
237 	     new->flags & KVM_MEM_LOG_DIRTY_PAGES)) {
238 		spin_lock(&kvm->mmu_lock);
239 		/* Write protect GPA page table entries */
240 		needs_flush = kvm_mips_mkclean_gpa_pt(kvm, new->base_gfn,
241 					new->base_gfn + new->npages - 1);
242 		if (needs_flush)
243 			kvm_arch_flush_remote_tlbs_memslot(kvm, new);
244 		spin_unlock(&kvm->mmu_lock);
245 	}
246 }
247 
248 static inline void dump_handler(const char *symbol, void *start, void *end)
249 {
250 	u32 *p;
251 
252 	pr_debug("LEAF(%s)\n", symbol);
253 
254 	pr_debug("\t.set push\n");
255 	pr_debug("\t.set noreorder\n");
256 
257 	for (p = start; p < (u32 *)end; ++p)
258 		pr_debug("\t.word\t0x%08x\t\t# %p\n", *p, p);
259 
260 	pr_debug("\t.set\tpop\n");
261 
262 	pr_debug("\tEND(%s)\n", symbol);
263 }
264 
265 /* low level hrtimer wake routine */
266 static enum hrtimer_restart kvm_mips_comparecount_wakeup(struct hrtimer *timer)
267 {
268 	struct kvm_vcpu *vcpu;
269 
270 	vcpu = container_of(timer, struct kvm_vcpu, arch.comparecount_timer);
271 
272 	kvm_mips_callbacks->queue_timer_int(vcpu);
273 
274 	vcpu->arch.wait = 0;
275 	rcuwait_wake_up(&vcpu->wait);
276 
277 	return kvm_mips_count_timeout(vcpu);
278 }
279 
280 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
281 {
282 	return 0;
283 }
284 
285 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
286 {
287 	int err, size;
288 	void *gebase, *p, *handler, *refill_start, *refill_end;
289 	int i;
290 
291 	kvm_debug("kvm @ %p: create cpu %d at %p\n",
292 		  vcpu->kvm, vcpu->vcpu_id, vcpu);
293 
294 	err = kvm_mips_callbacks->vcpu_init(vcpu);
295 	if (err)
296 		return err;
297 
298 	hrtimer_init(&vcpu->arch.comparecount_timer, CLOCK_MONOTONIC,
299 		     HRTIMER_MODE_REL);
300 	vcpu->arch.comparecount_timer.function = kvm_mips_comparecount_wakeup;
301 
302 	/*
303 	 * Allocate space for host mode exception handlers that handle
304 	 * guest mode exits
305 	 */
306 	if (cpu_has_veic || cpu_has_vint)
307 		size = 0x200 + VECTORSPACING * 64;
308 	else
309 		size = 0x4000;
310 
311 	gebase = kzalloc(ALIGN(size, PAGE_SIZE), GFP_KERNEL);
312 
313 	if (!gebase) {
314 		err = -ENOMEM;
315 		goto out_uninit_vcpu;
316 	}
317 	kvm_debug("Allocated %d bytes for KVM Exception Handlers @ %p\n",
318 		  ALIGN(size, PAGE_SIZE), gebase);
319 
320 	/*
321 	 * Check new ebase actually fits in CP0_EBase. The lack of a write gate
322 	 * limits us to the low 512MB of physical address space. If the memory
323 	 * we allocate is out of range, just give up now.
324 	 */
325 	if (!cpu_has_ebase_wg && virt_to_phys(gebase) >= 0x20000000) {
326 		kvm_err("CP0_EBase.WG required for guest exception base %pK\n",
327 			gebase);
328 		err = -ENOMEM;
329 		goto out_free_gebase;
330 	}
331 
332 	/* Save new ebase */
333 	vcpu->arch.guest_ebase = gebase;
334 
335 	/* Build guest exception vectors dynamically in unmapped memory */
336 	handler = gebase + 0x2000;
337 
338 	/* TLB refill (or XTLB refill on 64-bit VZ where KX=1) */
339 	refill_start = gebase;
340 	if (IS_ENABLED(CONFIG_64BIT))
341 		refill_start += 0x080;
342 	refill_end = kvm_mips_build_tlb_refill_exception(refill_start, handler);
343 
344 	/* General Exception Entry point */
345 	kvm_mips_build_exception(gebase + 0x180, handler);
346 
347 	/* For vectored interrupts poke the exception code @ all offsets 0-7 */
348 	for (i = 0; i < 8; i++) {
349 		kvm_debug("L1 Vectored handler @ %p\n",
350 			  gebase + 0x200 + (i * VECTORSPACING));
351 		kvm_mips_build_exception(gebase + 0x200 + i * VECTORSPACING,
352 					 handler);
353 	}
354 
355 	/* General exit handler */
356 	p = handler;
357 	p = kvm_mips_build_exit(p);
358 
359 	/* Guest entry routine */
360 	vcpu->arch.vcpu_run = p;
361 	p = kvm_mips_build_vcpu_run(p);
362 
363 	/* Dump the generated code */
364 	pr_debug("#include <asm/asm.h>\n");
365 	pr_debug("#include <asm/regdef.h>\n");
366 	pr_debug("\n");
367 	dump_handler("kvm_vcpu_run", vcpu->arch.vcpu_run, p);
368 	dump_handler("kvm_tlb_refill", refill_start, refill_end);
369 	dump_handler("kvm_gen_exc", gebase + 0x180, gebase + 0x200);
370 	dump_handler("kvm_exit", gebase + 0x2000, vcpu->arch.vcpu_run);
371 
372 	/* Invalidate the icache for these ranges */
373 	flush_icache_range((unsigned long)gebase,
374 			   (unsigned long)gebase + ALIGN(size, PAGE_SIZE));
375 
376 	/* Init */
377 	vcpu->arch.last_sched_cpu = -1;
378 	vcpu->arch.last_exec_cpu = -1;
379 
380 	/* Initial guest state */
381 	err = kvm_mips_callbacks->vcpu_setup(vcpu);
382 	if (err)
383 		goto out_free_gebase;
384 
385 	return 0;
386 
387 out_free_gebase:
388 	kfree(gebase);
389 out_uninit_vcpu:
390 	kvm_mips_callbacks->vcpu_uninit(vcpu);
391 	return err;
392 }
393 
394 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
395 {
396 	hrtimer_cancel(&vcpu->arch.comparecount_timer);
397 
398 	kvm_mips_dump_stats(vcpu);
399 
400 	kvm_mmu_free_memory_caches(vcpu);
401 	kfree(vcpu->arch.guest_ebase);
402 
403 	kvm_mips_callbacks->vcpu_uninit(vcpu);
404 }
405 
406 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
407 					struct kvm_guest_debug *dbg)
408 {
409 	return -ENOIOCTLCMD;
410 }
411 
412 /*
413  * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while
414  * the vCPU is running.
415  *
416  * This must be noinstr as instrumentation may make use of RCU, and this is not
417  * safe during the EQS.
418  */
419 static int noinstr kvm_mips_vcpu_enter_exit(struct kvm_vcpu *vcpu)
420 {
421 	int ret;
422 
423 	guest_state_enter_irqoff();
424 	ret = kvm_mips_callbacks->vcpu_run(vcpu);
425 	guest_state_exit_irqoff();
426 
427 	return ret;
428 }
429 
430 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
431 {
432 	int r = -EINTR;
433 
434 	vcpu_load(vcpu);
435 
436 	kvm_sigset_activate(vcpu);
437 
438 	if (vcpu->mmio_needed) {
439 		if (!vcpu->mmio_is_write)
440 			kvm_mips_complete_mmio_load(vcpu);
441 		vcpu->mmio_needed = 0;
442 	}
443 
444 	if (vcpu->run->immediate_exit)
445 		goto out;
446 
447 	lose_fpu(1);
448 
449 	local_irq_disable();
450 	guest_timing_enter_irqoff();
451 	trace_kvm_enter(vcpu);
452 
453 	/*
454 	 * Make sure the read of VCPU requests in vcpu_run() callback is not
455 	 * reordered ahead of the write to vcpu->mode, or we could miss a TLB
456 	 * flush request while the requester sees the VCPU as outside of guest
457 	 * mode and not needing an IPI.
458 	 */
459 	smp_store_mb(vcpu->mode, IN_GUEST_MODE);
460 
461 	r = kvm_mips_vcpu_enter_exit(vcpu);
462 
463 	/*
464 	 * We must ensure that any pending interrupts are taken before
465 	 * we exit guest timing so that timer ticks are accounted as
466 	 * guest time. Transiently unmask interrupts so that any
467 	 * pending interrupts are taken.
468 	 *
469 	 * TODO: is there a barrier which ensures that pending interrupts are
470 	 * recognised? Currently this just hopes that the CPU takes any pending
471 	 * interrupts between the enable and disable.
472 	 */
473 	local_irq_enable();
474 	local_irq_disable();
475 
476 	trace_kvm_out(vcpu);
477 	guest_timing_exit_irqoff();
478 	local_irq_enable();
479 
480 out:
481 	kvm_sigset_deactivate(vcpu);
482 
483 	vcpu_put(vcpu);
484 	return r;
485 }
486 
487 int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
488 			     struct kvm_mips_interrupt *irq)
489 {
490 	int intr = (int)irq->irq;
491 	struct kvm_vcpu *dvcpu = NULL;
492 
493 	if (intr == kvm_priority_to_irq[MIPS_EXC_INT_IPI_1] ||
494 	    intr == kvm_priority_to_irq[MIPS_EXC_INT_IPI_2] ||
495 	    intr == (-kvm_priority_to_irq[MIPS_EXC_INT_IPI_1]) ||
496 	    intr == (-kvm_priority_to_irq[MIPS_EXC_INT_IPI_2]))
497 		kvm_debug("%s: CPU: %d, INTR: %d\n", __func__, irq->cpu,
498 			  (int)intr);
499 
500 	if (irq->cpu == -1)
501 		dvcpu = vcpu;
502 	else
503 		dvcpu = kvm_get_vcpu(vcpu->kvm, irq->cpu);
504 
505 	if (intr == 2 || intr == 3 || intr == 4 || intr == 6) {
506 		kvm_mips_callbacks->queue_io_int(dvcpu, irq);
507 
508 	} else if (intr == -2 || intr == -3 || intr == -4 || intr == -6) {
509 		kvm_mips_callbacks->dequeue_io_int(dvcpu, irq);
510 	} else {
511 		kvm_err("%s: invalid interrupt ioctl (%d:%d)\n", __func__,
512 			irq->cpu, irq->irq);
513 		return -EINVAL;
514 	}
515 
516 	dvcpu->arch.wait = 0;
517 
518 	rcuwait_wake_up(&dvcpu->wait);
519 
520 	return 0;
521 }
522 
523 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
524 				    struct kvm_mp_state *mp_state)
525 {
526 	return -ENOIOCTLCMD;
527 }
528 
529 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
530 				    struct kvm_mp_state *mp_state)
531 {
532 	return -ENOIOCTLCMD;
533 }
534 
535 static u64 kvm_mips_get_one_regs[] = {
536 	KVM_REG_MIPS_R0,
537 	KVM_REG_MIPS_R1,
538 	KVM_REG_MIPS_R2,
539 	KVM_REG_MIPS_R3,
540 	KVM_REG_MIPS_R4,
541 	KVM_REG_MIPS_R5,
542 	KVM_REG_MIPS_R6,
543 	KVM_REG_MIPS_R7,
544 	KVM_REG_MIPS_R8,
545 	KVM_REG_MIPS_R9,
546 	KVM_REG_MIPS_R10,
547 	KVM_REG_MIPS_R11,
548 	KVM_REG_MIPS_R12,
549 	KVM_REG_MIPS_R13,
550 	KVM_REG_MIPS_R14,
551 	KVM_REG_MIPS_R15,
552 	KVM_REG_MIPS_R16,
553 	KVM_REG_MIPS_R17,
554 	KVM_REG_MIPS_R18,
555 	KVM_REG_MIPS_R19,
556 	KVM_REG_MIPS_R20,
557 	KVM_REG_MIPS_R21,
558 	KVM_REG_MIPS_R22,
559 	KVM_REG_MIPS_R23,
560 	KVM_REG_MIPS_R24,
561 	KVM_REG_MIPS_R25,
562 	KVM_REG_MIPS_R26,
563 	KVM_REG_MIPS_R27,
564 	KVM_REG_MIPS_R28,
565 	KVM_REG_MIPS_R29,
566 	KVM_REG_MIPS_R30,
567 	KVM_REG_MIPS_R31,
568 
569 #ifndef CONFIG_CPU_MIPSR6
570 	KVM_REG_MIPS_HI,
571 	KVM_REG_MIPS_LO,
572 #endif
573 	KVM_REG_MIPS_PC,
574 };
575 
576 static u64 kvm_mips_get_one_regs_fpu[] = {
577 	KVM_REG_MIPS_FCR_IR,
578 	KVM_REG_MIPS_FCR_CSR,
579 };
580 
581 static u64 kvm_mips_get_one_regs_msa[] = {
582 	KVM_REG_MIPS_MSA_IR,
583 	KVM_REG_MIPS_MSA_CSR,
584 };
585 
586 static unsigned long kvm_mips_num_regs(struct kvm_vcpu *vcpu)
587 {
588 	unsigned long ret;
589 
590 	ret = ARRAY_SIZE(kvm_mips_get_one_regs);
591 	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
592 		ret += ARRAY_SIZE(kvm_mips_get_one_regs_fpu) + 48;
593 		/* odd doubles */
594 		if (boot_cpu_data.fpu_id & MIPS_FPIR_F64)
595 			ret += 16;
596 	}
597 	if (kvm_mips_guest_can_have_msa(&vcpu->arch))
598 		ret += ARRAY_SIZE(kvm_mips_get_one_regs_msa) + 32;
599 	ret += kvm_mips_callbacks->num_regs(vcpu);
600 
601 	return ret;
602 }
603 
604 static int kvm_mips_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices)
605 {
606 	u64 index;
607 	unsigned int i;
608 
609 	if (copy_to_user(indices, kvm_mips_get_one_regs,
610 			 sizeof(kvm_mips_get_one_regs)))
611 		return -EFAULT;
612 	indices += ARRAY_SIZE(kvm_mips_get_one_regs);
613 
614 	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
615 		if (copy_to_user(indices, kvm_mips_get_one_regs_fpu,
616 				 sizeof(kvm_mips_get_one_regs_fpu)))
617 			return -EFAULT;
618 		indices += ARRAY_SIZE(kvm_mips_get_one_regs_fpu);
619 
620 		for (i = 0; i < 32; ++i) {
621 			index = KVM_REG_MIPS_FPR_32(i);
622 			if (copy_to_user(indices, &index, sizeof(index)))
623 				return -EFAULT;
624 			++indices;
625 
626 			/* skip odd doubles if no F64 */
627 			if (i & 1 && !(boot_cpu_data.fpu_id & MIPS_FPIR_F64))
628 				continue;
629 
630 			index = KVM_REG_MIPS_FPR_64(i);
631 			if (copy_to_user(indices, &index, sizeof(index)))
632 				return -EFAULT;
633 			++indices;
634 		}
635 	}
636 
637 	if (kvm_mips_guest_can_have_msa(&vcpu->arch)) {
638 		if (copy_to_user(indices, kvm_mips_get_one_regs_msa,
639 				 sizeof(kvm_mips_get_one_regs_msa)))
640 			return -EFAULT;
641 		indices += ARRAY_SIZE(kvm_mips_get_one_regs_msa);
642 
643 		for (i = 0; i < 32; ++i) {
644 			index = KVM_REG_MIPS_VEC_128(i);
645 			if (copy_to_user(indices, &index, sizeof(index)))
646 				return -EFAULT;
647 			++indices;
648 		}
649 	}
650 
651 	return kvm_mips_callbacks->copy_reg_indices(vcpu, indices);
652 }
653 
654 static int kvm_mips_get_reg(struct kvm_vcpu *vcpu,
655 			    const struct kvm_one_reg *reg)
656 {
657 	struct mips_coproc *cop0 = vcpu->arch.cop0;
658 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
659 	int ret;
660 	s64 v;
661 	s64 vs[2];
662 	unsigned int idx;
663 
664 	switch (reg->id) {
665 	/* General purpose registers */
666 	case KVM_REG_MIPS_R0 ... KVM_REG_MIPS_R31:
667 		v = (long)vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0];
668 		break;
669 #ifndef CONFIG_CPU_MIPSR6
670 	case KVM_REG_MIPS_HI:
671 		v = (long)vcpu->arch.hi;
672 		break;
673 	case KVM_REG_MIPS_LO:
674 		v = (long)vcpu->arch.lo;
675 		break;
676 #endif
677 	case KVM_REG_MIPS_PC:
678 		v = (long)vcpu->arch.pc;
679 		break;
680 
681 	/* Floating point registers */
682 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
683 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
684 			return -EINVAL;
685 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
686 		/* Odd singles in top of even double when FR=0 */
687 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
688 			v = get_fpr32(&fpu->fpr[idx], 0);
689 		else
690 			v = get_fpr32(&fpu->fpr[idx & ~1], idx & 1);
691 		break;
692 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
693 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
694 			return -EINVAL;
695 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
696 		/* Can't access odd doubles in FR=0 mode */
697 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
698 			return -EINVAL;
699 		v = get_fpr64(&fpu->fpr[idx], 0);
700 		break;
701 	case KVM_REG_MIPS_FCR_IR:
702 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
703 			return -EINVAL;
704 		v = boot_cpu_data.fpu_id;
705 		break;
706 	case KVM_REG_MIPS_FCR_CSR:
707 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
708 			return -EINVAL;
709 		v = fpu->fcr31;
710 		break;
711 
712 	/* MIPS SIMD Architecture (MSA) registers */
713 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
714 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
715 			return -EINVAL;
716 		/* Can't access MSA registers in FR=0 mode */
717 		if (!(kvm_read_c0_guest_status(cop0) & ST0_FR))
718 			return -EINVAL;
719 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
720 #ifdef CONFIG_CPU_LITTLE_ENDIAN
721 		/* least significant byte first */
722 		vs[0] = get_fpr64(&fpu->fpr[idx], 0);
723 		vs[1] = get_fpr64(&fpu->fpr[idx], 1);
724 #else
725 		/* most significant byte first */
726 		vs[0] = get_fpr64(&fpu->fpr[idx], 1);
727 		vs[1] = get_fpr64(&fpu->fpr[idx], 0);
728 #endif
729 		break;
730 	case KVM_REG_MIPS_MSA_IR:
731 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
732 			return -EINVAL;
733 		v = boot_cpu_data.msa_id;
734 		break;
735 	case KVM_REG_MIPS_MSA_CSR:
736 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
737 			return -EINVAL;
738 		v = fpu->msacsr;
739 		break;
740 
741 	/* registers to be handled specially */
742 	default:
743 		ret = kvm_mips_callbacks->get_one_reg(vcpu, reg, &v);
744 		if (ret)
745 			return ret;
746 		break;
747 	}
748 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
749 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
750 
751 		return put_user(v, uaddr64);
752 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
753 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
754 		u32 v32 = (u32)v;
755 
756 		return put_user(v32, uaddr32);
757 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
758 		void __user *uaddr = (void __user *)(long)reg->addr;
759 
760 		return copy_to_user(uaddr, vs, 16) ? -EFAULT : 0;
761 	} else {
762 		return -EINVAL;
763 	}
764 }
765 
766 static int kvm_mips_set_reg(struct kvm_vcpu *vcpu,
767 			    const struct kvm_one_reg *reg)
768 {
769 	struct mips_coproc *cop0 = vcpu->arch.cop0;
770 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
771 	s64 v;
772 	s64 vs[2];
773 	unsigned int idx;
774 
775 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
776 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
777 
778 		if (get_user(v, uaddr64) != 0)
779 			return -EFAULT;
780 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
781 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
782 		s32 v32;
783 
784 		if (get_user(v32, uaddr32) != 0)
785 			return -EFAULT;
786 		v = (s64)v32;
787 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
788 		void __user *uaddr = (void __user *)(long)reg->addr;
789 
790 		return copy_from_user(vs, uaddr, 16) ? -EFAULT : 0;
791 	} else {
792 		return -EINVAL;
793 	}
794 
795 	switch (reg->id) {
796 	/* General purpose registers */
797 	case KVM_REG_MIPS_R0:
798 		/* Silently ignore requests to set $0 */
799 		break;
800 	case KVM_REG_MIPS_R1 ... KVM_REG_MIPS_R31:
801 		vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0] = v;
802 		break;
803 #ifndef CONFIG_CPU_MIPSR6
804 	case KVM_REG_MIPS_HI:
805 		vcpu->arch.hi = v;
806 		break;
807 	case KVM_REG_MIPS_LO:
808 		vcpu->arch.lo = v;
809 		break;
810 #endif
811 	case KVM_REG_MIPS_PC:
812 		vcpu->arch.pc = v;
813 		break;
814 
815 	/* Floating point registers */
816 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
817 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
818 			return -EINVAL;
819 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
820 		/* Odd singles in top of even double when FR=0 */
821 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
822 			set_fpr32(&fpu->fpr[idx], 0, v);
823 		else
824 			set_fpr32(&fpu->fpr[idx & ~1], idx & 1, v);
825 		break;
826 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
827 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
828 			return -EINVAL;
829 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
830 		/* Can't access odd doubles in FR=0 mode */
831 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
832 			return -EINVAL;
833 		set_fpr64(&fpu->fpr[idx], 0, v);
834 		break;
835 	case KVM_REG_MIPS_FCR_IR:
836 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
837 			return -EINVAL;
838 		/* Read-only */
839 		break;
840 	case KVM_REG_MIPS_FCR_CSR:
841 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
842 			return -EINVAL;
843 		fpu->fcr31 = v;
844 		break;
845 
846 	/* MIPS SIMD Architecture (MSA) registers */
847 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
848 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
849 			return -EINVAL;
850 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
851 #ifdef CONFIG_CPU_LITTLE_ENDIAN
852 		/* least significant byte first */
853 		set_fpr64(&fpu->fpr[idx], 0, vs[0]);
854 		set_fpr64(&fpu->fpr[idx], 1, vs[1]);
855 #else
856 		/* most significant byte first */
857 		set_fpr64(&fpu->fpr[idx], 1, vs[0]);
858 		set_fpr64(&fpu->fpr[idx], 0, vs[1]);
859 #endif
860 		break;
861 	case KVM_REG_MIPS_MSA_IR:
862 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
863 			return -EINVAL;
864 		/* Read-only */
865 		break;
866 	case KVM_REG_MIPS_MSA_CSR:
867 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
868 			return -EINVAL;
869 		fpu->msacsr = v;
870 		break;
871 
872 	/* registers to be handled specially */
873 	default:
874 		return kvm_mips_callbacks->set_one_reg(vcpu, reg, v);
875 	}
876 	return 0;
877 }
878 
879 static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
880 				     struct kvm_enable_cap *cap)
881 {
882 	int r = 0;
883 
884 	if (!kvm_vm_ioctl_check_extension(vcpu->kvm, cap->cap))
885 		return -EINVAL;
886 	if (cap->flags)
887 		return -EINVAL;
888 	if (cap->args[0])
889 		return -EINVAL;
890 
891 	switch (cap->cap) {
892 	case KVM_CAP_MIPS_FPU:
893 		vcpu->arch.fpu_enabled = true;
894 		break;
895 	case KVM_CAP_MIPS_MSA:
896 		vcpu->arch.msa_enabled = true;
897 		break;
898 	default:
899 		r = -EINVAL;
900 		break;
901 	}
902 
903 	return r;
904 }
905 
906 long kvm_arch_vcpu_async_ioctl(struct file *filp, unsigned int ioctl,
907 			       unsigned long arg)
908 {
909 	struct kvm_vcpu *vcpu = filp->private_data;
910 	void __user *argp = (void __user *)arg;
911 
912 	if (ioctl == KVM_INTERRUPT) {
913 		struct kvm_mips_interrupt irq;
914 
915 		if (copy_from_user(&irq, argp, sizeof(irq)))
916 			return -EFAULT;
917 		kvm_debug("[%d] %s: irq: %d\n", vcpu->vcpu_id, __func__,
918 			  irq.irq);
919 
920 		return kvm_vcpu_ioctl_interrupt(vcpu, &irq);
921 	}
922 
923 	return -ENOIOCTLCMD;
924 }
925 
926 long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl,
927 			 unsigned long arg)
928 {
929 	struct kvm_vcpu *vcpu = filp->private_data;
930 	void __user *argp = (void __user *)arg;
931 	long r;
932 
933 	vcpu_load(vcpu);
934 
935 	switch (ioctl) {
936 	case KVM_SET_ONE_REG:
937 	case KVM_GET_ONE_REG: {
938 		struct kvm_one_reg reg;
939 
940 		r = -EFAULT;
941 		if (copy_from_user(&reg, argp, sizeof(reg)))
942 			break;
943 		if (ioctl == KVM_SET_ONE_REG)
944 			r = kvm_mips_set_reg(vcpu, &reg);
945 		else
946 			r = kvm_mips_get_reg(vcpu, &reg);
947 		break;
948 	}
949 	case KVM_GET_REG_LIST: {
950 		struct kvm_reg_list __user *user_list = argp;
951 		struct kvm_reg_list reg_list;
952 		unsigned n;
953 
954 		r = -EFAULT;
955 		if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
956 			break;
957 		n = reg_list.n;
958 		reg_list.n = kvm_mips_num_regs(vcpu);
959 		if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
960 			break;
961 		r = -E2BIG;
962 		if (n < reg_list.n)
963 			break;
964 		r = kvm_mips_copy_reg_indices(vcpu, user_list->reg);
965 		break;
966 	}
967 	case KVM_ENABLE_CAP: {
968 		struct kvm_enable_cap cap;
969 
970 		r = -EFAULT;
971 		if (copy_from_user(&cap, argp, sizeof(cap)))
972 			break;
973 		r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
974 		break;
975 	}
976 	default:
977 		r = -ENOIOCTLCMD;
978 	}
979 
980 	vcpu_put(vcpu);
981 	return r;
982 }
983 
984 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
985 {
986 
987 }
988 
989 int kvm_arch_flush_remote_tlb(struct kvm *kvm)
990 {
991 	kvm_mips_callbacks->prepare_flush_shadow(kvm);
992 	return 1;
993 }
994 
995 void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
996 					const struct kvm_memory_slot *memslot)
997 {
998 	kvm_flush_remote_tlbs(kvm);
999 }
1000 
1001 long kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
1002 {
1003 	long r;
1004 
1005 	switch (ioctl) {
1006 	default:
1007 		r = -ENOIOCTLCMD;
1008 	}
1009 
1010 	return r;
1011 }
1012 
1013 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
1014 				  struct kvm_sregs *sregs)
1015 {
1016 	return -ENOIOCTLCMD;
1017 }
1018 
1019 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
1020 				  struct kvm_sregs *sregs)
1021 {
1022 	return -ENOIOCTLCMD;
1023 }
1024 
1025 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
1026 {
1027 }
1028 
1029 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1030 {
1031 	return -ENOIOCTLCMD;
1032 }
1033 
1034 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1035 {
1036 	return -ENOIOCTLCMD;
1037 }
1038 
1039 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
1040 {
1041 	return VM_FAULT_SIGBUS;
1042 }
1043 
1044 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
1045 {
1046 	int r;
1047 
1048 	switch (ext) {
1049 	case KVM_CAP_ONE_REG:
1050 	case KVM_CAP_ENABLE_CAP:
1051 	case KVM_CAP_READONLY_MEM:
1052 	case KVM_CAP_SYNC_MMU:
1053 	case KVM_CAP_IMMEDIATE_EXIT:
1054 		r = 1;
1055 		break;
1056 	case KVM_CAP_NR_VCPUS:
1057 		r = min_t(unsigned int, num_online_cpus(), KVM_MAX_VCPUS);
1058 		break;
1059 	case KVM_CAP_MAX_VCPUS:
1060 		r = KVM_MAX_VCPUS;
1061 		break;
1062 	case KVM_CAP_MAX_VCPU_ID:
1063 		r = KVM_MAX_VCPU_IDS;
1064 		break;
1065 	case KVM_CAP_MIPS_FPU:
1066 		/* We don't handle systems with inconsistent cpu_has_fpu */
1067 		r = !!raw_cpu_has_fpu;
1068 		break;
1069 	case KVM_CAP_MIPS_MSA:
1070 		/*
1071 		 * We don't support MSA vector partitioning yet:
1072 		 * 1) It would require explicit support which can't be tested
1073 		 *    yet due to lack of support in current hardware.
1074 		 * 2) It extends the state that would need to be saved/restored
1075 		 *    by e.g. QEMU for migration.
1076 		 *
1077 		 * When vector partitioning hardware becomes available, support
1078 		 * could be added by requiring a flag when enabling
1079 		 * KVM_CAP_MIPS_MSA capability to indicate that userland knows
1080 		 * to save/restore the appropriate extra state.
1081 		 */
1082 		r = cpu_has_msa && !(boot_cpu_data.msa_id & MSA_IR_WRPF);
1083 		break;
1084 	default:
1085 		r = kvm_mips_callbacks->check_extension(kvm, ext);
1086 		break;
1087 	}
1088 	return r;
1089 }
1090 
1091 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
1092 {
1093 	return kvm_mips_pending_timer(vcpu) ||
1094 		kvm_read_c0_guest_cause(vcpu->arch.cop0) & C_TI;
1095 }
1096 
1097 int kvm_arch_vcpu_dump_regs(struct kvm_vcpu *vcpu)
1098 {
1099 	int i;
1100 	struct mips_coproc *cop0;
1101 
1102 	if (!vcpu)
1103 		return -1;
1104 
1105 	kvm_debug("VCPU Register Dump:\n");
1106 	kvm_debug("\tpc = 0x%08lx\n", vcpu->arch.pc);
1107 	kvm_debug("\texceptions: %08lx\n", vcpu->arch.pending_exceptions);
1108 
1109 	for (i = 0; i < 32; i += 4) {
1110 		kvm_debug("\tgpr%02d: %08lx %08lx %08lx %08lx\n", i,
1111 		       vcpu->arch.gprs[i],
1112 		       vcpu->arch.gprs[i + 1],
1113 		       vcpu->arch.gprs[i + 2], vcpu->arch.gprs[i + 3]);
1114 	}
1115 	kvm_debug("\thi: 0x%08lx\n", vcpu->arch.hi);
1116 	kvm_debug("\tlo: 0x%08lx\n", vcpu->arch.lo);
1117 
1118 	cop0 = vcpu->arch.cop0;
1119 	kvm_debug("\tStatus: 0x%08x, Cause: 0x%08x\n",
1120 		  kvm_read_c0_guest_status(cop0),
1121 		  kvm_read_c0_guest_cause(cop0));
1122 
1123 	kvm_debug("\tEPC: 0x%08lx\n", kvm_read_c0_guest_epc(cop0));
1124 
1125 	return 0;
1126 }
1127 
1128 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1129 {
1130 	int i;
1131 
1132 	vcpu_load(vcpu);
1133 
1134 	for (i = 1; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1135 		vcpu->arch.gprs[i] = regs->gpr[i];
1136 	vcpu->arch.gprs[0] = 0; /* zero is special, and cannot be set. */
1137 	vcpu->arch.hi = regs->hi;
1138 	vcpu->arch.lo = regs->lo;
1139 	vcpu->arch.pc = regs->pc;
1140 
1141 	vcpu_put(vcpu);
1142 	return 0;
1143 }
1144 
1145 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1146 {
1147 	int i;
1148 
1149 	vcpu_load(vcpu);
1150 
1151 	for (i = 0; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1152 		regs->gpr[i] = vcpu->arch.gprs[i];
1153 
1154 	regs->hi = vcpu->arch.hi;
1155 	regs->lo = vcpu->arch.lo;
1156 	regs->pc = vcpu->arch.pc;
1157 
1158 	vcpu_put(vcpu);
1159 	return 0;
1160 }
1161 
1162 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
1163 				  struct kvm_translation *tr)
1164 {
1165 	return 0;
1166 }
1167 
1168 static void kvm_mips_set_c0_status(void)
1169 {
1170 	u32 status = read_c0_status();
1171 
1172 	if (cpu_has_dsp)
1173 		status |= (ST0_MX);
1174 
1175 	write_c0_status(status);
1176 	ehb();
1177 }
1178 
1179 /*
1180  * Return value is in the form (errcode<<2 | RESUME_FLAG_HOST | RESUME_FLAG_NV)
1181  */
1182 static int __kvm_mips_handle_exit(struct kvm_vcpu *vcpu)
1183 {
1184 	struct kvm_run *run = vcpu->run;
1185 	u32 cause = vcpu->arch.host_cp0_cause;
1186 	u32 exccode = (cause >> CAUSEB_EXCCODE) & 0x1f;
1187 	u32 __user *opc = (u32 __user *) vcpu->arch.pc;
1188 	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
1189 	enum emulation_result er = EMULATE_DONE;
1190 	u32 inst;
1191 	int ret = RESUME_GUEST;
1192 
1193 	vcpu->mode = OUTSIDE_GUEST_MODE;
1194 
1195 	/* Set a default exit reason */
1196 	run->exit_reason = KVM_EXIT_UNKNOWN;
1197 	run->ready_for_interrupt_injection = 1;
1198 
1199 	/*
1200 	 * Set the appropriate status bits based on host CPU features,
1201 	 * before we hit the scheduler
1202 	 */
1203 	kvm_mips_set_c0_status();
1204 
1205 	local_irq_enable();
1206 
1207 	kvm_debug("kvm_mips_handle_exit: cause: %#x, PC: %p, kvm_run: %p, kvm_vcpu: %p\n",
1208 			cause, opc, run, vcpu);
1209 	trace_kvm_exit(vcpu, exccode);
1210 
1211 	switch (exccode) {
1212 	case EXCCODE_INT:
1213 		kvm_debug("[%d]EXCCODE_INT @ %p\n", vcpu->vcpu_id, opc);
1214 
1215 		++vcpu->stat.int_exits;
1216 
1217 		if (need_resched())
1218 			cond_resched();
1219 
1220 		ret = RESUME_GUEST;
1221 		break;
1222 
1223 	case EXCCODE_CPU:
1224 		kvm_debug("EXCCODE_CPU: @ PC: %p\n", opc);
1225 
1226 		++vcpu->stat.cop_unusable_exits;
1227 		ret = kvm_mips_callbacks->handle_cop_unusable(vcpu);
1228 		/* XXXKYMA: Might need to return to user space */
1229 		if (run->exit_reason == KVM_EXIT_IRQ_WINDOW_OPEN)
1230 			ret = RESUME_HOST;
1231 		break;
1232 
1233 	case EXCCODE_MOD:
1234 		++vcpu->stat.tlbmod_exits;
1235 		ret = kvm_mips_callbacks->handle_tlb_mod(vcpu);
1236 		break;
1237 
1238 	case EXCCODE_TLBS:
1239 		kvm_debug("TLB ST fault:  cause %#x, status %#x, PC: %p, BadVaddr: %#lx\n",
1240 			  cause, kvm_read_c0_guest_status(vcpu->arch.cop0), opc,
1241 			  badvaddr);
1242 
1243 		++vcpu->stat.tlbmiss_st_exits;
1244 		ret = kvm_mips_callbacks->handle_tlb_st_miss(vcpu);
1245 		break;
1246 
1247 	case EXCCODE_TLBL:
1248 		kvm_debug("TLB LD fault: cause %#x, PC: %p, BadVaddr: %#lx\n",
1249 			  cause, opc, badvaddr);
1250 
1251 		++vcpu->stat.tlbmiss_ld_exits;
1252 		ret = kvm_mips_callbacks->handle_tlb_ld_miss(vcpu);
1253 		break;
1254 
1255 	case EXCCODE_ADES:
1256 		++vcpu->stat.addrerr_st_exits;
1257 		ret = kvm_mips_callbacks->handle_addr_err_st(vcpu);
1258 		break;
1259 
1260 	case EXCCODE_ADEL:
1261 		++vcpu->stat.addrerr_ld_exits;
1262 		ret = kvm_mips_callbacks->handle_addr_err_ld(vcpu);
1263 		break;
1264 
1265 	case EXCCODE_SYS:
1266 		++vcpu->stat.syscall_exits;
1267 		ret = kvm_mips_callbacks->handle_syscall(vcpu);
1268 		break;
1269 
1270 	case EXCCODE_RI:
1271 		++vcpu->stat.resvd_inst_exits;
1272 		ret = kvm_mips_callbacks->handle_res_inst(vcpu);
1273 		break;
1274 
1275 	case EXCCODE_BP:
1276 		++vcpu->stat.break_inst_exits;
1277 		ret = kvm_mips_callbacks->handle_break(vcpu);
1278 		break;
1279 
1280 	case EXCCODE_TR:
1281 		++vcpu->stat.trap_inst_exits;
1282 		ret = kvm_mips_callbacks->handle_trap(vcpu);
1283 		break;
1284 
1285 	case EXCCODE_MSAFPE:
1286 		++vcpu->stat.msa_fpe_exits;
1287 		ret = kvm_mips_callbacks->handle_msa_fpe(vcpu);
1288 		break;
1289 
1290 	case EXCCODE_FPE:
1291 		++vcpu->stat.fpe_exits;
1292 		ret = kvm_mips_callbacks->handle_fpe(vcpu);
1293 		break;
1294 
1295 	case EXCCODE_MSADIS:
1296 		++vcpu->stat.msa_disabled_exits;
1297 		ret = kvm_mips_callbacks->handle_msa_disabled(vcpu);
1298 		break;
1299 
1300 	case EXCCODE_GE:
1301 		/* defer exit accounting to handler */
1302 		ret = kvm_mips_callbacks->handle_guest_exit(vcpu);
1303 		break;
1304 
1305 	default:
1306 		if (cause & CAUSEF_BD)
1307 			opc += 1;
1308 		inst = 0;
1309 		kvm_get_badinstr(opc, vcpu, &inst);
1310 		kvm_err("Exception Code: %d, not yet handled, @ PC: %p, inst: 0x%08x  BadVaddr: %#lx Status: %#x\n",
1311 			exccode, opc, inst, badvaddr,
1312 			kvm_read_c0_guest_status(vcpu->arch.cop0));
1313 		kvm_arch_vcpu_dump_regs(vcpu);
1314 		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1315 		ret = RESUME_HOST;
1316 		break;
1317 
1318 	}
1319 
1320 	local_irq_disable();
1321 
1322 	if (ret == RESUME_GUEST)
1323 		kvm_vz_acquire_htimer(vcpu);
1324 
1325 	if (er == EMULATE_DONE && !(ret & RESUME_HOST))
1326 		kvm_mips_deliver_interrupts(vcpu, cause);
1327 
1328 	if (!(ret & RESUME_HOST)) {
1329 		/* Only check for signals if not already exiting to userspace */
1330 		if (signal_pending(current)) {
1331 			run->exit_reason = KVM_EXIT_INTR;
1332 			ret = (-EINTR << 2) | RESUME_HOST;
1333 			++vcpu->stat.signal_exits;
1334 			trace_kvm_exit(vcpu, KVM_TRACE_EXIT_SIGNAL);
1335 		}
1336 	}
1337 
1338 	if (ret == RESUME_GUEST) {
1339 		trace_kvm_reenter(vcpu);
1340 
1341 		/*
1342 		 * Make sure the read of VCPU requests in vcpu_reenter()
1343 		 * callback is not reordered ahead of the write to vcpu->mode,
1344 		 * or we could miss a TLB flush request while the requester sees
1345 		 * the VCPU as outside of guest mode and not needing an IPI.
1346 		 */
1347 		smp_store_mb(vcpu->mode, IN_GUEST_MODE);
1348 
1349 		kvm_mips_callbacks->vcpu_reenter(vcpu);
1350 
1351 		/*
1352 		 * If FPU / MSA are enabled (i.e. the guest's FPU / MSA context
1353 		 * is live), restore FCR31 / MSACSR.
1354 		 *
1355 		 * This should be before returning to the guest exception
1356 		 * vector, as it may well cause an [MSA] FP exception if there
1357 		 * are pending exception bits unmasked. (see
1358 		 * kvm_mips_csr_die_notifier() for how that is handled).
1359 		 */
1360 		if (kvm_mips_guest_has_fpu(&vcpu->arch) &&
1361 		    read_c0_status() & ST0_CU1)
1362 			__kvm_restore_fcsr(&vcpu->arch);
1363 
1364 		if (kvm_mips_guest_has_msa(&vcpu->arch) &&
1365 		    read_c0_config5() & MIPS_CONF5_MSAEN)
1366 			__kvm_restore_msacsr(&vcpu->arch);
1367 	}
1368 	return ret;
1369 }
1370 
1371 int noinstr kvm_mips_handle_exit(struct kvm_vcpu *vcpu)
1372 {
1373 	int ret;
1374 
1375 	guest_state_exit_irqoff();
1376 	ret = __kvm_mips_handle_exit(vcpu);
1377 	guest_state_enter_irqoff();
1378 
1379 	return ret;
1380 }
1381 
1382 /* Enable FPU for guest and restore context */
1383 void kvm_own_fpu(struct kvm_vcpu *vcpu)
1384 {
1385 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1386 	unsigned int sr, cfg5;
1387 
1388 	preempt_disable();
1389 
1390 	sr = kvm_read_c0_guest_status(cop0);
1391 
1392 	/*
1393 	 * If MSA state is already live, it is undefined how it interacts with
1394 	 * FR=0 FPU state, and we don't want to hit reserved instruction
1395 	 * exceptions trying to save the MSA state later when CU=1 && FR=1, so
1396 	 * play it safe and save it first.
1397 	 */
1398 	if (cpu_has_msa && sr & ST0_CU1 && !(sr & ST0_FR) &&
1399 	    vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA)
1400 		kvm_lose_fpu(vcpu);
1401 
1402 	/*
1403 	 * Enable FPU for guest
1404 	 * We set FR and FRE according to guest context
1405 	 */
1406 	change_c0_status(ST0_CU1 | ST0_FR, sr);
1407 	if (cpu_has_fre) {
1408 		cfg5 = kvm_read_c0_guest_config5(cop0);
1409 		change_c0_config5(MIPS_CONF5_FRE, cfg5);
1410 	}
1411 	enable_fpu_hazard();
1412 
1413 	/* If guest FPU state not active, restore it now */
1414 	if (!(vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU)) {
1415 		__kvm_restore_fpu(&vcpu->arch);
1416 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1417 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_FPU);
1418 	} else {
1419 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_FPU);
1420 	}
1421 
1422 	preempt_enable();
1423 }
1424 
1425 #ifdef CONFIG_CPU_HAS_MSA
1426 /* Enable MSA for guest and restore context */
1427 void kvm_own_msa(struct kvm_vcpu *vcpu)
1428 {
1429 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1430 	unsigned int sr, cfg5;
1431 
1432 	preempt_disable();
1433 
1434 	/*
1435 	 * Enable FPU if enabled in guest, since we're restoring FPU context
1436 	 * anyway. We set FR and FRE according to guest context.
1437 	 */
1438 	if (kvm_mips_guest_has_fpu(&vcpu->arch)) {
1439 		sr = kvm_read_c0_guest_status(cop0);
1440 
1441 		/*
1442 		 * If FR=0 FPU state is already live, it is undefined how it
1443 		 * interacts with MSA state, so play it safe and save it first.
1444 		 */
1445 		if (!(sr & ST0_FR) &&
1446 		    (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU |
1447 				KVM_MIPS_AUX_MSA)) == KVM_MIPS_AUX_FPU)
1448 			kvm_lose_fpu(vcpu);
1449 
1450 		change_c0_status(ST0_CU1 | ST0_FR, sr);
1451 		if (sr & ST0_CU1 && cpu_has_fre) {
1452 			cfg5 = kvm_read_c0_guest_config5(cop0);
1453 			change_c0_config5(MIPS_CONF5_FRE, cfg5);
1454 		}
1455 	}
1456 
1457 	/* Enable MSA for guest */
1458 	set_c0_config5(MIPS_CONF5_MSAEN);
1459 	enable_fpu_hazard();
1460 
1461 	switch (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA)) {
1462 	case KVM_MIPS_AUX_FPU:
1463 		/*
1464 		 * Guest FPU state already loaded, only restore upper MSA state
1465 		 */
1466 		__kvm_restore_msa_upper(&vcpu->arch);
1467 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1468 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_MSA);
1469 		break;
1470 	case 0:
1471 		/* Neither FPU or MSA already active, restore full MSA state */
1472 		__kvm_restore_msa(&vcpu->arch);
1473 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1474 		if (kvm_mips_guest_has_fpu(&vcpu->arch))
1475 			vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1476 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE,
1477 			      KVM_TRACE_AUX_FPU_MSA);
1478 		break;
1479 	default:
1480 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_MSA);
1481 		break;
1482 	}
1483 
1484 	preempt_enable();
1485 }
1486 #endif
1487 
1488 /* Drop FPU & MSA without saving it */
1489 void kvm_drop_fpu(struct kvm_vcpu *vcpu)
1490 {
1491 	preempt_disable();
1492 	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1493 		disable_msa();
1494 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_MSA);
1495 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_MSA;
1496 	}
1497 	if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1498 		clear_c0_status(ST0_CU1 | ST0_FR);
1499 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_FPU);
1500 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1501 	}
1502 	preempt_enable();
1503 }
1504 
1505 /* Save and disable FPU & MSA */
1506 void kvm_lose_fpu(struct kvm_vcpu *vcpu)
1507 {
1508 	/*
1509 	 * With T&E, FPU & MSA get disabled in root context (hardware) when it
1510 	 * is disabled in guest context (software), but the register state in
1511 	 * the hardware may still be in use.
1512 	 * This is why we explicitly re-enable the hardware before saving.
1513 	 */
1514 
1515 	preempt_disable();
1516 	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1517 		__kvm_save_msa(&vcpu->arch);
1518 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU_MSA);
1519 
1520 		/* Disable MSA & FPU */
1521 		disable_msa();
1522 		if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1523 			clear_c0_status(ST0_CU1 | ST0_FR);
1524 			disable_fpu_hazard();
1525 		}
1526 		vcpu->arch.aux_inuse &= ~(KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA);
1527 	} else if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1528 		__kvm_save_fpu(&vcpu->arch);
1529 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1530 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU);
1531 
1532 		/* Disable FPU */
1533 		clear_c0_status(ST0_CU1 | ST0_FR);
1534 		disable_fpu_hazard();
1535 	}
1536 	preempt_enable();
1537 }
1538 
1539 /*
1540  * Step over a specific ctc1 to FCSR and a specific ctcmsa to MSACSR which are
1541  * used to restore guest FCSR/MSACSR state and may trigger a "harmless" FP/MSAFP
1542  * exception if cause bits are set in the value being written.
1543  */
1544 static int kvm_mips_csr_die_notify(struct notifier_block *self,
1545 				   unsigned long cmd, void *ptr)
1546 {
1547 	struct die_args *args = (struct die_args *)ptr;
1548 	struct pt_regs *regs = args->regs;
1549 	unsigned long pc;
1550 
1551 	/* Only interested in FPE and MSAFPE */
1552 	if (cmd != DIE_FP && cmd != DIE_MSAFP)
1553 		return NOTIFY_DONE;
1554 
1555 	/* Return immediately if guest context isn't active */
1556 	if (!(current->flags & PF_VCPU))
1557 		return NOTIFY_DONE;
1558 
1559 	/* Should never get here from user mode */
1560 	BUG_ON(user_mode(regs));
1561 
1562 	pc = instruction_pointer(regs);
1563 	switch (cmd) {
1564 	case DIE_FP:
1565 		/* match 2nd instruction in __kvm_restore_fcsr */
1566 		if (pc != (unsigned long)&__kvm_restore_fcsr + 4)
1567 			return NOTIFY_DONE;
1568 		break;
1569 	case DIE_MSAFP:
1570 		/* match 2nd/3rd instruction in __kvm_restore_msacsr */
1571 		if (!cpu_has_msa ||
1572 		    pc < (unsigned long)&__kvm_restore_msacsr + 4 ||
1573 		    pc > (unsigned long)&__kvm_restore_msacsr + 8)
1574 			return NOTIFY_DONE;
1575 		break;
1576 	}
1577 
1578 	/* Move PC forward a little and continue executing */
1579 	instruction_pointer(regs) += 4;
1580 
1581 	return NOTIFY_STOP;
1582 }
1583 
1584 static struct notifier_block kvm_mips_csr_die_notifier = {
1585 	.notifier_call = kvm_mips_csr_die_notify,
1586 };
1587 
1588 static u32 kvm_default_priority_to_irq[MIPS_EXC_MAX] = {
1589 	[MIPS_EXC_INT_TIMER] = C_IRQ5,
1590 	[MIPS_EXC_INT_IO_1]  = C_IRQ0,
1591 	[MIPS_EXC_INT_IPI_1] = C_IRQ1,
1592 	[MIPS_EXC_INT_IPI_2] = C_IRQ2,
1593 };
1594 
1595 static u32 kvm_loongson3_priority_to_irq[MIPS_EXC_MAX] = {
1596 	[MIPS_EXC_INT_TIMER] = C_IRQ5,
1597 	[MIPS_EXC_INT_IO_1]  = C_IRQ0,
1598 	[MIPS_EXC_INT_IO_2]  = C_IRQ1,
1599 	[MIPS_EXC_INT_IPI_1] = C_IRQ4,
1600 };
1601 
1602 u32 *kvm_priority_to_irq = kvm_default_priority_to_irq;
1603 
1604 u32 kvm_irq_to_priority(u32 irq)
1605 {
1606 	int i;
1607 
1608 	for (i = MIPS_EXC_INT_TIMER; i < MIPS_EXC_MAX; i++) {
1609 		if (kvm_priority_to_irq[i] == (1 << (irq + 8)))
1610 			return i;
1611 	}
1612 
1613 	return MIPS_EXC_MAX;
1614 }
1615 
1616 static int __init kvm_mips_init(void)
1617 {
1618 	int ret;
1619 
1620 	if (cpu_has_mmid) {
1621 		pr_warn("KVM does not yet support MMIDs. KVM Disabled\n");
1622 		return -EOPNOTSUPP;
1623 	}
1624 
1625 	ret = kvm_mips_entry_setup();
1626 	if (ret)
1627 		return ret;
1628 
1629 	ret = kvm_mips_emulation_init();
1630 	if (ret)
1631 		return ret;
1632 
1633 
1634 	if (boot_cpu_type() == CPU_LOONGSON64)
1635 		kvm_priority_to_irq = kvm_loongson3_priority_to_irq;
1636 
1637 	register_die_notifier(&kvm_mips_csr_die_notifier);
1638 
1639 	ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
1640 	if (ret) {
1641 		unregister_die_notifier(&kvm_mips_csr_die_notifier);
1642 		return ret;
1643 	}
1644 	return 0;
1645 }
1646 
1647 static void __exit kvm_mips_exit(void)
1648 {
1649 	kvm_exit();
1650 
1651 	unregister_die_notifier(&kvm_mips_csr_die_notifier);
1652 }
1653 
1654 module_init(kvm_mips_init);
1655 module_exit(kvm_mips_exit);
1656 
1657 EXPORT_TRACEPOINT_SYMBOL(kvm_exit);
1658