xref: /linux/arch/mips/kvm/mips.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
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_enable_virtualization_cpu(void)
129 {
130 	return kvm_mips_callbacks->enable_virtualization_cpu();
131 }
132 
133 void kvm_arch_disable_virtualization_cpu(void)
134 {
135 	kvm_mips_callbacks->disable_virtualization_cpu();
136 }
137 
138 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
139 {
140 	switch (type) {
141 	case KVM_VM_MIPS_AUTO:
142 		break;
143 	case KVM_VM_MIPS_VZ:
144 		break;
145 	default:
146 		/* Unsupported KVM type */
147 		return -EINVAL;
148 	}
149 
150 	/* Allocate page table to map GPA -> RPA */
151 	kvm->arch.gpa_mm.pgd = kvm_pgd_alloc();
152 	if (!kvm->arch.gpa_mm.pgd)
153 		return -ENOMEM;
154 
155 #ifdef CONFIG_CPU_LOONGSON64
156 	kvm_init_loongson_ipi(kvm);
157 #endif
158 
159 	return 0;
160 }
161 
162 static void kvm_mips_free_gpa_pt(struct kvm *kvm)
163 {
164 	/* It should always be safe to remove after flushing the whole range */
165 	WARN_ON(!kvm_mips_flush_gpa_pt(kvm, 0, ~0));
166 	pgd_free(NULL, kvm->arch.gpa_mm.pgd);
167 }
168 
169 void kvm_arch_destroy_vm(struct kvm *kvm)
170 {
171 	kvm_destroy_vcpus(kvm);
172 	kvm_mips_free_gpa_pt(kvm);
173 }
174 
175 long kvm_arch_dev_ioctl(struct file *filp, unsigned int ioctl,
176 			unsigned long arg)
177 {
178 	return -ENOIOCTLCMD;
179 }
180 
181 void kvm_arch_flush_shadow_all(struct kvm *kvm)
182 {
183 	/* Flush whole GPA */
184 	kvm_mips_flush_gpa_pt(kvm, 0, ~0);
185 	kvm_flush_remote_tlbs(kvm);
186 }
187 
188 void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
189 				   struct kvm_memory_slot *slot)
190 {
191 	/*
192 	 * The slot has been made invalid (ready for moving or deletion), so we
193 	 * need to ensure that it can no longer be accessed by any guest VCPUs.
194 	 */
195 
196 	spin_lock(&kvm->mmu_lock);
197 	/* Flush slot from GPA */
198 	kvm_mips_flush_gpa_pt(kvm, slot->base_gfn,
199 			      slot->base_gfn + slot->npages - 1);
200 	kvm_flush_remote_tlbs_memslot(kvm, slot);
201 	spin_unlock(&kvm->mmu_lock);
202 }
203 
204 int kvm_arch_prepare_memory_region(struct kvm *kvm,
205 				   const struct kvm_memory_slot *old,
206 				   struct kvm_memory_slot *new,
207 				   enum kvm_mr_change change)
208 {
209 	return 0;
210 }
211 
212 void kvm_arch_commit_memory_region(struct kvm *kvm,
213 				   struct kvm_memory_slot *old,
214 				   const struct kvm_memory_slot *new,
215 				   enum kvm_mr_change change)
216 {
217 	int needs_flush;
218 
219 	/*
220 	 * If dirty page logging is enabled, write protect all pages in the slot
221 	 * ready for dirty logging.
222 	 *
223 	 * There is no need to do this in any of the following cases:
224 	 * CREATE:	No dirty mappings will already exist.
225 	 * MOVE/DELETE:	The old mappings will already have been cleaned up by
226 	 *		kvm_arch_flush_shadow_memslot()
227 	 */
228 	if (change == KVM_MR_FLAGS_ONLY &&
229 	    (!(old->flags & KVM_MEM_LOG_DIRTY_PAGES) &&
230 	     new->flags & KVM_MEM_LOG_DIRTY_PAGES)) {
231 		spin_lock(&kvm->mmu_lock);
232 		/* Write protect GPA page table entries */
233 		needs_flush = kvm_mips_mkclean_gpa_pt(kvm, new->base_gfn,
234 					new->base_gfn + new->npages - 1);
235 		if (needs_flush)
236 			kvm_flush_remote_tlbs_memslot(kvm, new);
237 		spin_unlock(&kvm->mmu_lock);
238 	}
239 }
240 
241 static inline void dump_handler(const char *symbol, void *start, void *end)
242 {
243 	u32 *p;
244 
245 	pr_debug("LEAF(%s)\n", symbol);
246 
247 	pr_debug("\t.set push\n");
248 	pr_debug("\t.set noreorder\n");
249 
250 	for (p = start; p < (u32 *)end; ++p)
251 		pr_debug("\t.word\t0x%08x\t\t# %p\n", *p, p);
252 
253 	pr_debug("\t.set\tpop\n");
254 
255 	pr_debug("\tEND(%s)\n", symbol);
256 }
257 
258 /* low level hrtimer wake routine */
259 static enum hrtimer_restart kvm_mips_comparecount_wakeup(struct hrtimer *timer)
260 {
261 	struct kvm_vcpu *vcpu;
262 
263 	vcpu = container_of(timer, struct kvm_vcpu, arch.comparecount_timer);
264 
265 	kvm_mips_callbacks->queue_timer_int(vcpu);
266 
267 	vcpu->arch.wait = 0;
268 	rcuwait_wake_up(&vcpu->wait);
269 
270 	return kvm_mips_count_timeout(vcpu);
271 }
272 
273 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
274 {
275 	return 0;
276 }
277 
278 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
279 {
280 	int err, size;
281 	void *gebase, *p, *handler, *refill_start, *refill_end;
282 	int i;
283 
284 	kvm_debug("kvm @ %p: create cpu %d at %p\n",
285 		  vcpu->kvm, vcpu->vcpu_id, vcpu);
286 
287 	err = kvm_mips_callbacks->vcpu_init(vcpu);
288 	if (err)
289 		return err;
290 
291 	hrtimer_init(&vcpu->arch.comparecount_timer, CLOCK_MONOTONIC,
292 		     HRTIMER_MODE_REL);
293 	vcpu->arch.comparecount_timer.function = kvm_mips_comparecount_wakeup;
294 
295 	/*
296 	 * Allocate space for host mode exception handlers that handle
297 	 * guest mode exits
298 	 */
299 	if (cpu_has_veic || cpu_has_vint)
300 		size = 0x200 + VECTORSPACING * 64;
301 	else
302 		size = 0x4000;
303 
304 	gebase = kzalloc(ALIGN(size, PAGE_SIZE), GFP_KERNEL);
305 
306 	if (!gebase) {
307 		err = -ENOMEM;
308 		goto out_uninit_vcpu;
309 	}
310 	kvm_debug("Allocated %d bytes for KVM Exception Handlers @ %p\n",
311 		  ALIGN(size, PAGE_SIZE), gebase);
312 
313 	/*
314 	 * Check new ebase actually fits in CP0_EBase. The lack of a write gate
315 	 * limits us to the low 512MB of physical address space. If the memory
316 	 * we allocate is out of range, just give up now.
317 	 */
318 	if (!cpu_has_ebase_wg && virt_to_phys(gebase) >= 0x20000000) {
319 		kvm_err("CP0_EBase.WG required for guest exception base %pK\n",
320 			gebase);
321 		err = -ENOMEM;
322 		goto out_free_gebase;
323 	}
324 
325 	/* Save new ebase */
326 	vcpu->arch.guest_ebase = gebase;
327 
328 	/* Build guest exception vectors dynamically in unmapped memory */
329 	handler = gebase + 0x2000;
330 
331 	/* TLB refill (or XTLB refill on 64-bit VZ where KX=1) */
332 	refill_start = gebase;
333 	if (IS_ENABLED(CONFIG_64BIT))
334 		refill_start += 0x080;
335 	refill_end = kvm_mips_build_tlb_refill_exception(refill_start, handler);
336 
337 	/* General Exception Entry point */
338 	kvm_mips_build_exception(gebase + 0x180, handler);
339 
340 	/* For vectored interrupts poke the exception code @ all offsets 0-7 */
341 	for (i = 0; i < 8; i++) {
342 		kvm_debug("L1 Vectored handler @ %p\n",
343 			  gebase + 0x200 + (i * VECTORSPACING));
344 		kvm_mips_build_exception(gebase + 0x200 + i * VECTORSPACING,
345 					 handler);
346 	}
347 
348 	/* General exit handler */
349 	p = handler;
350 	p = kvm_mips_build_exit(p);
351 
352 	/* Guest entry routine */
353 	vcpu->arch.vcpu_run = p;
354 	p = kvm_mips_build_vcpu_run(p);
355 
356 	/* Dump the generated code */
357 	pr_debug("#include <asm/asm.h>\n");
358 	pr_debug("#include <asm/regdef.h>\n");
359 	pr_debug("\n");
360 	dump_handler("kvm_vcpu_run", vcpu->arch.vcpu_run, p);
361 	dump_handler("kvm_tlb_refill", refill_start, refill_end);
362 	dump_handler("kvm_gen_exc", gebase + 0x180, gebase + 0x200);
363 	dump_handler("kvm_exit", gebase + 0x2000, vcpu->arch.vcpu_run);
364 
365 	/* Invalidate the icache for these ranges */
366 	flush_icache_range((unsigned long)gebase,
367 			   (unsigned long)gebase + ALIGN(size, PAGE_SIZE));
368 
369 	/* Init */
370 	vcpu->arch.last_sched_cpu = -1;
371 	vcpu->arch.last_exec_cpu = -1;
372 
373 	/* Initial guest state */
374 	err = kvm_mips_callbacks->vcpu_setup(vcpu);
375 	if (err)
376 		goto out_free_gebase;
377 
378 	return 0;
379 
380 out_free_gebase:
381 	kfree(gebase);
382 out_uninit_vcpu:
383 	kvm_mips_callbacks->vcpu_uninit(vcpu);
384 	return err;
385 }
386 
387 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
388 {
389 	hrtimer_cancel(&vcpu->arch.comparecount_timer);
390 
391 	kvm_mips_dump_stats(vcpu);
392 
393 	kvm_mmu_free_memory_caches(vcpu);
394 	kfree(vcpu->arch.guest_ebase);
395 
396 	kvm_mips_callbacks->vcpu_uninit(vcpu);
397 }
398 
399 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
400 					struct kvm_guest_debug *dbg)
401 {
402 	return -ENOIOCTLCMD;
403 }
404 
405 /*
406  * Actually run the vCPU, entering an RCU extended quiescent state (EQS) while
407  * the vCPU is running.
408  *
409  * This must be noinstr as instrumentation may make use of RCU, and this is not
410  * safe during the EQS.
411  */
412 static int noinstr kvm_mips_vcpu_enter_exit(struct kvm_vcpu *vcpu)
413 {
414 	int ret;
415 
416 	guest_state_enter_irqoff();
417 	ret = kvm_mips_callbacks->vcpu_run(vcpu);
418 	guest_state_exit_irqoff();
419 
420 	return ret;
421 }
422 
423 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
424 {
425 	int r = -EINTR;
426 
427 	vcpu_load(vcpu);
428 
429 	kvm_sigset_activate(vcpu);
430 
431 	if (vcpu->mmio_needed) {
432 		if (!vcpu->mmio_is_write)
433 			kvm_mips_complete_mmio_load(vcpu);
434 		vcpu->mmio_needed = 0;
435 	}
436 
437 	if (!vcpu->wants_to_run)
438 		goto out;
439 
440 	lose_fpu(1);
441 
442 	local_irq_disable();
443 	guest_timing_enter_irqoff();
444 	trace_kvm_enter(vcpu);
445 
446 	/*
447 	 * Make sure the read of VCPU requests in vcpu_run() callback is not
448 	 * reordered ahead of the write to vcpu->mode, or we could miss a TLB
449 	 * flush request while the requester sees the VCPU as outside of guest
450 	 * mode and not needing an IPI.
451 	 */
452 	smp_store_mb(vcpu->mode, IN_GUEST_MODE);
453 
454 	r = kvm_mips_vcpu_enter_exit(vcpu);
455 
456 	/*
457 	 * We must ensure that any pending interrupts are taken before
458 	 * we exit guest timing so that timer ticks are accounted as
459 	 * guest time. Transiently unmask interrupts so that any
460 	 * pending interrupts are taken.
461 	 *
462 	 * TODO: is there a barrier which ensures that pending interrupts are
463 	 * recognised? Currently this just hopes that the CPU takes any pending
464 	 * interrupts between the enable and disable.
465 	 */
466 	local_irq_enable();
467 	local_irq_disable();
468 
469 	trace_kvm_out(vcpu);
470 	guest_timing_exit_irqoff();
471 	local_irq_enable();
472 
473 out:
474 	kvm_sigset_deactivate(vcpu);
475 
476 	vcpu_put(vcpu);
477 	return r;
478 }
479 
480 int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
481 			     struct kvm_mips_interrupt *irq)
482 {
483 	int intr = (int)irq->irq;
484 	struct kvm_vcpu *dvcpu = NULL;
485 
486 	if (intr == kvm_priority_to_irq[MIPS_EXC_INT_IPI_1] ||
487 	    intr == kvm_priority_to_irq[MIPS_EXC_INT_IPI_2] ||
488 	    intr == (-kvm_priority_to_irq[MIPS_EXC_INT_IPI_1]) ||
489 	    intr == (-kvm_priority_to_irq[MIPS_EXC_INT_IPI_2]))
490 		kvm_debug("%s: CPU: %d, INTR: %d\n", __func__, irq->cpu,
491 			  (int)intr);
492 
493 	if (irq->cpu == -1)
494 		dvcpu = vcpu;
495 	else
496 		dvcpu = kvm_get_vcpu(vcpu->kvm, irq->cpu);
497 
498 	if (intr == 2 || intr == 3 || intr == 4 || intr == 6) {
499 		kvm_mips_callbacks->queue_io_int(dvcpu, irq);
500 
501 	} else if (intr == -2 || intr == -3 || intr == -4 || intr == -6) {
502 		kvm_mips_callbacks->dequeue_io_int(dvcpu, irq);
503 	} else {
504 		kvm_err("%s: invalid interrupt ioctl (%d:%d)\n", __func__,
505 			irq->cpu, irq->irq);
506 		return -EINVAL;
507 	}
508 
509 	dvcpu->arch.wait = 0;
510 
511 	rcuwait_wake_up(&dvcpu->wait);
512 
513 	return 0;
514 }
515 
516 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
517 				    struct kvm_mp_state *mp_state)
518 {
519 	return -ENOIOCTLCMD;
520 }
521 
522 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
523 				    struct kvm_mp_state *mp_state)
524 {
525 	return -ENOIOCTLCMD;
526 }
527 
528 static u64 kvm_mips_get_one_regs[] = {
529 	KVM_REG_MIPS_R0,
530 	KVM_REG_MIPS_R1,
531 	KVM_REG_MIPS_R2,
532 	KVM_REG_MIPS_R3,
533 	KVM_REG_MIPS_R4,
534 	KVM_REG_MIPS_R5,
535 	KVM_REG_MIPS_R6,
536 	KVM_REG_MIPS_R7,
537 	KVM_REG_MIPS_R8,
538 	KVM_REG_MIPS_R9,
539 	KVM_REG_MIPS_R10,
540 	KVM_REG_MIPS_R11,
541 	KVM_REG_MIPS_R12,
542 	KVM_REG_MIPS_R13,
543 	KVM_REG_MIPS_R14,
544 	KVM_REG_MIPS_R15,
545 	KVM_REG_MIPS_R16,
546 	KVM_REG_MIPS_R17,
547 	KVM_REG_MIPS_R18,
548 	KVM_REG_MIPS_R19,
549 	KVM_REG_MIPS_R20,
550 	KVM_REG_MIPS_R21,
551 	KVM_REG_MIPS_R22,
552 	KVM_REG_MIPS_R23,
553 	KVM_REG_MIPS_R24,
554 	KVM_REG_MIPS_R25,
555 	KVM_REG_MIPS_R26,
556 	KVM_REG_MIPS_R27,
557 	KVM_REG_MIPS_R28,
558 	KVM_REG_MIPS_R29,
559 	KVM_REG_MIPS_R30,
560 	KVM_REG_MIPS_R31,
561 
562 #ifndef CONFIG_CPU_MIPSR6
563 	KVM_REG_MIPS_HI,
564 	KVM_REG_MIPS_LO,
565 #endif
566 	KVM_REG_MIPS_PC,
567 };
568 
569 static u64 kvm_mips_get_one_regs_fpu[] = {
570 	KVM_REG_MIPS_FCR_IR,
571 	KVM_REG_MIPS_FCR_CSR,
572 };
573 
574 static u64 kvm_mips_get_one_regs_msa[] = {
575 	KVM_REG_MIPS_MSA_IR,
576 	KVM_REG_MIPS_MSA_CSR,
577 };
578 
579 static unsigned long kvm_mips_num_regs(struct kvm_vcpu *vcpu)
580 {
581 	unsigned long ret;
582 
583 	ret = ARRAY_SIZE(kvm_mips_get_one_regs);
584 	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
585 		ret += ARRAY_SIZE(kvm_mips_get_one_regs_fpu) + 48;
586 		/* odd doubles */
587 		if (boot_cpu_data.fpu_id & MIPS_FPIR_F64)
588 			ret += 16;
589 	}
590 	if (kvm_mips_guest_can_have_msa(&vcpu->arch))
591 		ret += ARRAY_SIZE(kvm_mips_get_one_regs_msa) + 32;
592 	ret += kvm_mips_callbacks->num_regs(vcpu);
593 
594 	return ret;
595 }
596 
597 static int kvm_mips_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices)
598 {
599 	u64 index;
600 	unsigned int i;
601 
602 	if (copy_to_user(indices, kvm_mips_get_one_regs,
603 			 sizeof(kvm_mips_get_one_regs)))
604 		return -EFAULT;
605 	indices += ARRAY_SIZE(kvm_mips_get_one_regs);
606 
607 	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
608 		if (copy_to_user(indices, kvm_mips_get_one_regs_fpu,
609 				 sizeof(kvm_mips_get_one_regs_fpu)))
610 			return -EFAULT;
611 		indices += ARRAY_SIZE(kvm_mips_get_one_regs_fpu);
612 
613 		for (i = 0; i < 32; ++i) {
614 			index = KVM_REG_MIPS_FPR_32(i);
615 			if (copy_to_user(indices, &index, sizeof(index)))
616 				return -EFAULT;
617 			++indices;
618 
619 			/* skip odd doubles if no F64 */
620 			if (i & 1 && !(boot_cpu_data.fpu_id & MIPS_FPIR_F64))
621 				continue;
622 
623 			index = KVM_REG_MIPS_FPR_64(i);
624 			if (copy_to_user(indices, &index, sizeof(index)))
625 				return -EFAULT;
626 			++indices;
627 		}
628 	}
629 
630 	if (kvm_mips_guest_can_have_msa(&vcpu->arch)) {
631 		if (copy_to_user(indices, kvm_mips_get_one_regs_msa,
632 				 sizeof(kvm_mips_get_one_regs_msa)))
633 			return -EFAULT;
634 		indices += ARRAY_SIZE(kvm_mips_get_one_regs_msa);
635 
636 		for (i = 0; i < 32; ++i) {
637 			index = KVM_REG_MIPS_VEC_128(i);
638 			if (copy_to_user(indices, &index, sizeof(index)))
639 				return -EFAULT;
640 			++indices;
641 		}
642 	}
643 
644 	return kvm_mips_callbacks->copy_reg_indices(vcpu, indices);
645 }
646 
647 static int kvm_mips_get_reg(struct kvm_vcpu *vcpu,
648 			    const struct kvm_one_reg *reg)
649 {
650 	struct mips_coproc *cop0 = &vcpu->arch.cop0;
651 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
652 	int ret;
653 	s64 v;
654 	s64 vs[2];
655 	unsigned int idx;
656 
657 	switch (reg->id) {
658 	/* General purpose registers */
659 	case KVM_REG_MIPS_R0 ... KVM_REG_MIPS_R31:
660 		v = (long)vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0];
661 		break;
662 #ifndef CONFIG_CPU_MIPSR6
663 	case KVM_REG_MIPS_HI:
664 		v = (long)vcpu->arch.hi;
665 		break;
666 	case KVM_REG_MIPS_LO:
667 		v = (long)vcpu->arch.lo;
668 		break;
669 #endif
670 	case KVM_REG_MIPS_PC:
671 		v = (long)vcpu->arch.pc;
672 		break;
673 
674 	/* Floating point registers */
675 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
676 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
677 			return -EINVAL;
678 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
679 		/* Odd singles in top of even double when FR=0 */
680 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
681 			v = get_fpr32(&fpu->fpr[idx], 0);
682 		else
683 			v = get_fpr32(&fpu->fpr[idx & ~1], idx & 1);
684 		break;
685 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
686 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
687 			return -EINVAL;
688 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
689 		/* Can't access odd doubles in FR=0 mode */
690 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
691 			return -EINVAL;
692 		v = get_fpr64(&fpu->fpr[idx], 0);
693 		break;
694 	case KVM_REG_MIPS_FCR_IR:
695 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
696 			return -EINVAL;
697 		v = boot_cpu_data.fpu_id;
698 		break;
699 	case KVM_REG_MIPS_FCR_CSR:
700 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
701 			return -EINVAL;
702 		v = fpu->fcr31;
703 		break;
704 
705 	/* MIPS SIMD Architecture (MSA) registers */
706 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
707 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
708 			return -EINVAL;
709 		/* Can't access MSA registers in FR=0 mode */
710 		if (!(kvm_read_c0_guest_status(cop0) & ST0_FR))
711 			return -EINVAL;
712 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
713 #ifdef CONFIG_CPU_LITTLE_ENDIAN
714 		/* least significant byte first */
715 		vs[0] = get_fpr64(&fpu->fpr[idx], 0);
716 		vs[1] = get_fpr64(&fpu->fpr[idx], 1);
717 #else
718 		/* most significant byte first */
719 		vs[0] = get_fpr64(&fpu->fpr[idx], 1);
720 		vs[1] = get_fpr64(&fpu->fpr[idx], 0);
721 #endif
722 		break;
723 	case KVM_REG_MIPS_MSA_IR:
724 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
725 			return -EINVAL;
726 		v = boot_cpu_data.msa_id;
727 		break;
728 	case KVM_REG_MIPS_MSA_CSR:
729 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
730 			return -EINVAL;
731 		v = fpu->msacsr;
732 		break;
733 
734 	/* registers to be handled specially */
735 	default:
736 		ret = kvm_mips_callbacks->get_one_reg(vcpu, reg, &v);
737 		if (ret)
738 			return ret;
739 		break;
740 	}
741 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
742 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
743 
744 		return put_user(v, uaddr64);
745 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
746 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
747 		u32 v32 = (u32)v;
748 
749 		return put_user(v32, uaddr32);
750 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
751 		void __user *uaddr = (void __user *)(long)reg->addr;
752 
753 		return copy_to_user(uaddr, vs, 16) ? -EFAULT : 0;
754 	} else {
755 		return -EINVAL;
756 	}
757 }
758 
759 static int kvm_mips_set_reg(struct kvm_vcpu *vcpu,
760 			    const struct kvm_one_reg *reg)
761 {
762 	struct mips_coproc *cop0 = &vcpu->arch.cop0;
763 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
764 	s64 v;
765 	s64 vs[2];
766 	unsigned int idx;
767 
768 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
769 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
770 
771 		if (get_user(v, uaddr64) != 0)
772 			return -EFAULT;
773 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
774 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
775 		s32 v32;
776 
777 		if (get_user(v32, uaddr32) != 0)
778 			return -EFAULT;
779 		v = (s64)v32;
780 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
781 		void __user *uaddr = (void __user *)(long)reg->addr;
782 
783 		return copy_from_user(vs, uaddr, 16) ? -EFAULT : 0;
784 	} else {
785 		return -EINVAL;
786 	}
787 
788 	switch (reg->id) {
789 	/* General purpose registers */
790 	case KVM_REG_MIPS_R0:
791 		/* Silently ignore requests to set $0 */
792 		break;
793 	case KVM_REG_MIPS_R1 ... KVM_REG_MIPS_R31:
794 		vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0] = v;
795 		break;
796 #ifndef CONFIG_CPU_MIPSR6
797 	case KVM_REG_MIPS_HI:
798 		vcpu->arch.hi = v;
799 		break;
800 	case KVM_REG_MIPS_LO:
801 		vcpu->arch.lo = v;
802 		break;
803 #endif
804 	case KVM_REG_MIPS_PC:
805 		vcpu->arch.pc = v;
806 		break;
807 
808 	/* Floating point registers */
809 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
810 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
811 			return -EINVAL;
812 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
813 		/* Odd singles in top of even double when FR=0 */
814 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
815 			set_fpr32(&fpu->fpr[idx], 0, v);
816 		else
817 			set_fpr32(&fpu->fpr[idx & ~1], idx & 1, v);
818 		break;
819 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
820 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
821 			return -EINVAL;
822 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
823 		/* Can't access odd doubles in FR=0 mode */
824 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
825 			return -EINVAL;
826 		set_fpr64(&fpu->fpr[idx], 0, v);
827 		break;
828 	case KVM_REG_MIPS_FCR_IR:
829 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
830 			return -EINVAL;
831 		/* Read-only */
832 		break;
833 	case KVM_REG_MIPS_FCR_CSR:
834 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
835 			return -EINVAL;
836 		fpu->fcr31 = v;
837 		break;
838 
839 	/* MIPS SIMD Architecture (MSA) registers */
840 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
841 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
842 			return -EINVAL;
843 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
844 #ifdef CONFIG_CPU_LITTLE_ENDIAN
845 		/* least significant byte first */
846 		set_fpr64(&fpu->fpr[idx], 0, vs[0]);
847 		set_fpr64(&fpu->fpr[idx], 1, vs[1]);
848 #else
849 		/* most significant byte first */
850 		set_fpr64(&fpu->fpr[idx], 1, vs[0]);
851 		set_fpr64(&fpu->fpr[idx], 0, vs[1]);
852 #endif
853 		break;
854 	case KVM_REG_MIPS_MSA_IR:
855 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
856 			return -EINVAL;
857 		/* Read-only */
858 		break;
859 	case KVM_REG_MIPS_MSA_CSR:
860 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
861 			return -EINVAL;
862 		fpu->msacsr = v;
863 		break;
864 
865 	/* registers to be handled specially */
866 	default:
867 		return kvm_mips_callbacks->set_one_reg(vcpu, reg, v);
868 	}
869 	return 0;
870 }
871 
872 static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
873 				     struct kvm_enable_cap *cap)
874 {
875 	int r = 0;
876 
877 	if (!kvm_vm_ioctl_check_extension(vcpu->kvm, cap->cap))
878 		return -EINVAL;
879 	if (cap->flags)
880 		return -EINVAL;
881 	if (cap->args[0])
882 		return -EINVAL;
883 
884 	switch (cap->cap) {
885 	case KVM_CAP_MIPS_FPU:
886 		vcpu->arch.fpu_enabled = true;
887 		break;
888 	case KVM_CAP_MIPS_MSA:
889 		vcpu->arch.msa_enabled = true;
890 		break;
891 	default:
892 		r = -EINVAL;
893 		break;
894 	}
895 
896 	return r;
897 }
898 
899 long kvm_arch_vcpu_async_ioctl(struct file *filp, unsigned int ioctl,
900 			       unsigned long arg)
901 {
902 	struct kvm_vcpu *vcpu = filp->private_data;
903 	void __user *argp = (void __user *)arg;
904 
905 	if (ioctl == KVM_INTERRUPT) {
906 		struct kvm_mips_interrupt irq;
907 
908 		if (copy_from_user(&irq, argp, sizeof(irq)))
909 			return -EFAULT;
910 		kvm_debug("[%d] %s: irq: %d\n", vcpu->vcpu_id, __func__,
911 			  irq.irq);
912 
913 		return kvm_vcpu_ioctl_interrupt(vcpu, &irq);
914 	}
915 
916 	return -ENOIOCTLCMD;
917 }
918 
919 long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl,
920 			 unsigned long arg)
921 {
922 	struct kvm_vcpu *vcpu = filp->private_data;
923 	void __user *argp = (void __user *)arg;
924 	long r;
925 
926 	vcpu_load(vcpu);
927 
928 	switch (ioctl) {
929 	case KVM_SET_ONE_REG:
930 	case KVM_GET_ONE_REG: {
931 		struct kvm_one_reg reg;
932 
933 		r = -EFAULT;
934 		if (copy_from_user(&reg, argp, sizeof(reg)))
935 			break;
936 		if (ioctl == KVM_SET_ONE_REG)
937 			r = kvm_mips_set_reg(vcpu, &reg);
938 		else
939 			r = kvm_mips_get_reg(vcpu, &reg);
940 		break;
941 	}
942 	case KVM_GET_REG_LIST: {
943 		struct kvm_reg_list __user *user_list = argp;
944 		struct kvm_reg_list reg_list;
945 		unsigned n;
946 
947 		r = -EFAULT;
948 		if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
949 			break;
950 		n = reg_list.n;
951 		reg_list.n = kvm_mips_num_regs(vcpu);
952 		if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
953 			break;
954 		r = -E2BIG;
955 		if (n < reg_list.n)
956 			break;
957 		r = kvm_mips_copy_reg_indices(vcpu, user_list->reg);
958 		break;
959 	}
960 	case KVM_ENABLE_CAP: {
961 		struct kvm_enable_cap cap;
962 
963 		r = -EFAULT;
964 		if (copy_from_user(&cap, argp, sizeof(cap)))
965 			break;
966 		r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
967 		break;
968 	}
969 	default:
970 		r = -ENOIOCTLCMD;
971 	}
972 
973 	vcpu_put(vcpu);
974 	return r;
975 }
976 
977 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
978 {
979 
980 }
981 
982 int kvm_arch_flush_remote_tlbs(struct kvm *kvm)
983 {
984 	kvm_mips_callbacks->prepare_flush_shadow(kvm);
985 	return 1;
986 }
987 
988 int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
989 {
990 	int r;
991 
992 	switch (ioctl) {
993 	default:
994 		r = -ENOIOCTLCMD;
995 	}
996 
997 	return r;
998 }
999 
1000 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
1001 				  struct kvm_sregs *sregs)
1002 {
1003 	return -ENOIOCTLCMD;
1004 }
1005 
1006 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
1007 				  struct kvm_sregs *sregs)
1008 {
1009 	return -ENOIOCTLCMD;
1010 }
1011 
1012 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
1013 {
1014 }
1015 
1016 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1017 {
1018 	return -ENOIOCTLCMD;
1019 }
1020 
1021 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1022 {
1023 	return -ENOIOCTLCMD;
1024 }
1025 
1026 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
1027 {
1028 	return VM_FAULT_SIGBUS;
1029 }
1030 
1031 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
1032 {
1033 	int r;
1034 
1035 	switch (ext) {
1036 	case KVM_CAP_ONE_REG:
1037 	case KVM_CAP_ENABLE_CAP:
1038 	case KVM_CAP_READONLY_MEM:
1039 	case KVM_CAP_SYNC_MMU:
1040 	case KVM_CAP_IMMEDIATE_EXIT:
1041 		r = 1;
1042 		break;
1043 	case KVM_CAP_NR_VCPUS:
1044 		r = min_t(unsigned int, num_online_cpus(), KVM_MAX_VCPUS);
1045 		break;
1046 	case KVM_CAP_MAX_VCPUS:
1047 		r = KVM_MAX_VCPUS;
1048 		break;
1049 	case KVM_CAP_MAX_VCPU_ID:
1050 		r = KVM_MAX_VCPU_IDS;
1051 		break;
1052 	case KVM_CAP_MIPS_FPU:
1053 		/* We don't handle systems with inconsistent cpu_has_fpu */
1054 		r = !!raw_cpu_has_fpu;
1055 		break;
1056 	case KVM_CAP_MIPS_MSA:
1057 		/*
1058 		 * We don't support MSA vector partitioning yet:
1059 		 * 1) It would require explicit support which can't be tested
1060 		 *    yet due to lack of support in current hardware.
1061 		 * 2) It extends the state that would need to be saved/restored
1062 		 *    by e.g. QEMU for migration.
1063 		 *
1064 		 * When vector partitioning hardware becomes available, support
1065 		 * could be added by requiring a flag when enabling
1066 		 * KVM_CAP_MIPS_MSA capability to indicate that userland knows
1067 		 * to save/restore the appropriate extra state.
1068 		 */
1069 		r = cpu_has_msa && !(boot_cpu_data.msa_id & MSA_IR_WRPF);
1070 		break;
1071 	default:
1072 		r = kvm_mips_callbacks->check_extension(kvm, ext);
1073 		break;
1074 	}
1075 	return r;
1076 }
1077 
1078 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
1079 {
1080 	return kvm_mips_pending_timer(vcpu) ||
1081 		kvm_read_c0_guest_cause(&vcpu->arch.cop0) & C_TI;
1082 }
1083 
1084 int kvm_arch_vcpu_dump_regs(struct kvm_vcpu *vcpu)
1085 {
1086 	int i;
1087 	struct mips_coproc *cop0;
1088 
1089 	if (!vcpu)
1090 		return -1;
1091 
1092 	kvm_debug("VCPU Register Dump:\n");
1093 	kvm_debug("\tpc = 0x%08lx\n", vcpu->arch.pc);
1094 	kvm_debug("\texceptions: %08lx\n", vcpu->arch.pending_exceptions);
1095 
1096 	for (i = 0; i < 32; i += 4) {
1097 		kvm_debug("\tgpr%02d: %08lx %08lx %08lx %08lx\n", i,
1098 		       vcpu->arch.gprs[i],
1099 		       vcpu->arch.gprs[i + 1],
1100 		       vcpu->arch.gprs[i + 2], vcpu->arch.gprs[i + 3]);
1101 	}
1102 	kvm_debug("\thi: 0x%08lx\n", vcpu->arch.hi);
1103 	kvm_debug("\tlo: 0x%08lx\n", vcpu->arch.lo);
1104 
1105 	cop0 = &vcpu->arch.cop0;
1106 	kvm_debug("\tStatus: 0x%08x, Cause: 0x%08x\n",
1107 		  kvm_read_c0_guest_status(cop0),
1108 		  kvm_read_c0_guest_cause(cop0));
1109 
1110 	kvm_debug("\tEPC: 0x%08lx\n", kvm_read_c0_guest_epc(cop0));
1111 
1112 	return 0;
1113 }
1114 
1115 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1116 {
1117 	int i;
1118 
1119 	vcpu_load(vcpu);
1120 
1121 	for (i = 1; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1122 		vcpu->arch.gprs[i] = regs->gpr[i];
1123 	vcpu->arch.gprs[0] = 0; /* zero is special, and cannot be set. */
1124 	vcpu->arch.hi = regs->hi;
1125 	vcpu->arch.lo = regs->lo;
1126 	vcpu->arch.pc = regs->pc;
1127 
1128 	vcpu_put(vcpu);
1129 	return 0;
1130 }
1131 
1132 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1133 {
1134 	int i;
1135 
1136 	vcpu_load(vcpu);
1137 
1138 	for (i = 0; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1139 		regs->gpr[i] = vcpu->arch.gprs[i];
1140 
1141 	regs->hi = vcpu->arch.hi;
1142 	regs->lo = vcpu->arch.lo;
1143 	regs->pc = vcpu->arch.pc;
1144 
1145 	vcpu_put(vcpu);
1146 	return 0;
1147 }
1148 
1149 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
1150 				  struct kvm_translation *tr)
1151 {
1152 	return 0;
1153 }
1154 
1155 static void kvm_mips_set_c0_status(void)
1156 {
1157 	u32 status = read_c0_status();
1158 
1159 	if (cpu_has_dsp)
1160 		status |= (ST0_MX);
1161 
1162 	write_c0_status(status);
1163 	ehb();
1164 }
1165 
1166 /*
1167  * Return value is in the form (errcode<<2 | RESUME_FLAG_HOST | RESUME_FLAG_NV)
1168  */
1169 static int __kvm_mips_handle_exit(struct kvm_vcpu *vcpu)
1170 {
1171 	struct kvm_run *run = vcpu->run;
1172 	u32 cause = vcpu->arch.host_cp0_cause;
1173 	u32 exccode = (cause >> CAUSEB_EXCCODE) & 0x1f;
1174 	u32 __user *opc = (u32 __user *) vcpu->arch.pc;
1175 	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
1176 	enum emulation_result er = EMULATE_DONE;
1177 	u32 inst;
1178 	int ret = RESUME_GUEST;
1179 
1180 	vcpu->mode = OUTSIDE_GUEST_MODE;
1181 
1182 	/* Set a default exit reason */
1183 	run->exit_reason = KVM_EXIT_UNKNOWN;
1184 	run->ready_for_interrupt_injection = 1;
1185 
1186 	/*
1187 	 * Set the appropriate status bits based on host CPU features,
1188 	 * before we hit the scheduler
1189 	 */
1190 	kvm_mips_set_c0_status();
1191 
1192 	local_irq_enable();
1193 
1194 	kvm_debug("kvm_mips_handle_exit: cause: %#x, PC: %p, kvm_run: %p, kvm_vcpu: %p\n",
1195 			cause, opc, run, vcpu);
1196 	trace_kvm_exit(vcpu, exccode);
1197 
1198 	switch (exccode) {
1199 	case EXCCODE_INT:
1200 		kvm_debug("[%d]EXCCODE_INT @ %p\n", vcpu->vcpu_id, opc);
1201 
1202 		++vcpu->stat.int_exits;
1203 
1204 		if (need_resched())
1205 			cond_resched();
1206 
1207 		ret = RESUME_GUEST;
1208 		break;
1209 
1210 	case EXCCODE_CPU:
1211 		kvm_debug("EXCCODE_CPU: @ PC: %p\n", opc);
1212 
1213 		++vcpu->stat.cop_unusable_exits;
1214 		ret = kvm_mips_callbacks->handle_cop_unusable(vcpu);
1215 		/* XXXKYMA: Might need to return to user space */
1216 		if (run->exit_reason == KVM_EXIT_IRQ_WINDOW_OPEN)
1217 			ret = RESUME_HOST;
1218 		break;
1219 
1220 	case EXCCODE_MOD:
1221 		++vcpu->stat.tlbmod_exits;
1222 		ret = kvm_mips_callbacks->handle_tlb_mod(vcpu);
1223 		break;
1224 
1225 	case EXCCODE_TLBS:
1226 		kvm_debug("TLB ST fault:  cause %#x, status %#x, PC: %p, BadVaddr: %#lx\n",
1227 			  cause, kvm_read_c0_guest_status(&vcpu->arch.cop0), opc,
1228 			  badvaddr);
1229 
1230 		++vcpu->stat.tlbmiss_st_exits;
1231 		ret = kvm_mips_callbacks->handle_tlb_st_miss(vcpu);
1232 		break;
1233 
1234 	case EXCCODE_TLBL:
1235 		kvm_debug("TLB LD fault: cause %#x, PC: %p, BadVaddr: %#lx\n",
1236 			  cause, opc, badvaddr);
1237 
1238 		++vcpu->stat.tlbmiss_ld_exits;
1239 		ret = kvm_mips_callbacks->handle_tlb_ld_miss(vcpu);
1240 		break;
1241 
1242 	case EXCCODE_ADES:
1243 		++vcpu->stat.addrerr_st_exits;
1244 		ret = kvm_mips_callbacks->handle_addr_err_st(vcpu);
1245 		break;
1246 
1247 	case EXCCODE_ADEL:
1248 		++vcpu->stat.addrerr_ld_exits;
1249 		ret = kvm_mips_callbacks->handle_addr_err_ld(vcpu);
1250 		break;
1251 
1252 	case EXCCODE_SYS:
1253 		++vcpu->stat.syscall_exits;
1254 		ret = kvm_mips_callbacks->handle_syscall(vcpu);
1255 		break;
1256 
1257 	case EXCCODE_RI:
1258 		++vcpu->stat.resvd_inst_exits;
1259 		ret = kvm_mips_callbacks->handle_res_inst(vcpu);
1260 		break;
1261 
1262 	case EXCCODE_BP:
1263 		++vcpu->stat.break_inst_exits;
1264 		ret = kvm_mips_callbacks->handle_break(vcpu);
1265 		break;
1266 
1267 	case EXCCODE_TR:
1268 		++vcpu->stat.trap_inst_exits;
1269 		ret = kvm_mips_callbacks->handle_trap(vcpu);
1270 		break;
1271 
1272 	case EXCCODE_MSAFPE:
1273 		++vcpu->stat.msa_fpe_exits;
1274 		ret = kvm_mips_callbacks->handle_msa_fpe(vcpu);
1275 		break;
1276 
1277 	case EXCCODE_FPE:
1278 		++vcpu->stat.fpe_exits;
1279 		ret = kvm_mips_callbacks->handle_fpe(vcpu);
1280 		break;
1281 
1282 	case EXCCODE_MSADIS:
1283 		++vcpu->stat.msa_disabled_exits;
1284 		ret = kvm_mips_callbacks->handle_msa_disabled(vcpu);
1285 		break;
1286 
1287 	case EXCCODE_GE:
1288 		/* defer exit accounting to handler */
1289 		ret = kvm_mips_callbacks->handle_guest_exit(vcpu);
1290 		break;
1291 
1292 	default:
1293 		if (cause & CAUSEF_BD)
1294 			opc += 1;
1295 		inst = 0;
1296 		kvm_get_badinstr(opc, vcpu, &inst);
1297 		kvm_err("Exception Code: %d, not yet handled, @ PC: %p, inst: 0x%08x  BadVaddr: %#lx Status: %#x\n",
1298 			exccode, opc, inst, badvaddr,
1299 			kvm_read_c0_guest_status(&vcpu->arch.cop0));
1300 		kvm_arch_vcpu_dump_regs(vcpu);
1301 		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1302 		ret = RESUME_HOST;
1303 		break;
1304 
1305 	}
1306 
1307 	local_irq_disable();
1308 
1309 	if (ret == RESUME_GUEST)
1310 		kvm_vz_acquire_htimer(vcpu);
1311 
1312 	if (er == EMULATE_DONE && !(ret & RESUME_HOST))
1313 		kvm_mips_deliver_interrupts(vcpu, cause);
1314 
1315 	if (!(ret & RESUME_HOST)) {
1316 		/* Only check for signals if not already exiting to userspace */
1317 		if (signal_pending(current)) {
1318 			run->exit_reason = KVM_EXIT_INTR;
1319 			ret = (-EINTR << 2) | RESUME_HOST;
1320 			++vcpu->stat.signal_exits;
1321 			trace_kvm_exit(vcpu, KVM_TRACE_EXIT_SIGNAL);
1322 		}
1323 	}
1324 
1325 	if (ret == RESUME_GUEST) {
1326 		trace_kvm_reenter(vcpu);
1327 
1328 		/*
1329 		 * Make sure the read of VCPU requests in vcpu_reenter()
1330 		 * callback is not reordered ahead of the write to vcpu->mode,
1331 		 * or we could miss a TLB flush request while the requester sees
1332 		 * the VCPU as outside of guest mode and not needing an IPI.
1333 		 */
1334 		smp_store_mb(vcpu->mode, IN_GUEST_MODE);
1335 
1336 		kvm_mips_callbacks->vcpu_reenter(vcpu);
1337 
1338 		/*
1339 		 * If FPU / MSA are enabled (i.e. the guest's FPU / MSA context
1340 		 * is live), restore FCR31 / MSACSR.
1341 		 *
1342 		 * This should be before returning to the guest exception
1343 		 * vector, as it may well cause an [MSA] FP exception if there
1344 		 * are pending exception bits unmasked. (see
1345 		 * kvm_mips_csr_die_notifier() for how that is handled).
1346 		 */
1347 		if (kvm_mips_guest_has_fpu(&vcpu->arch) &&
1348 		    read_c0_status() & ST0_CU1)
1349 			__kvm_restore_fcsr(&vcpu->arch);
1350 
1351 		if (kvm_mips_guest_has_msa(&vcpu->arch) &&
1352 		    read_c0_config5() & MIPS_CONF5_MSAEN)
1353 			__kvm_restore_msacsr(&vcpu->arch);
1354 	}
1355 	return ret;
1356 }
1357 
1358 int noinstr kvm_mips_handle_exit(struct kvm_vcpu *vcpu)
1359 {
1360 	int ret;
1361 
1362 	guest_state_exit_irqoff();
1363 	ret = __kvm_mips_handle_exit(vcpu);
1364 	guest_state_enter_irqoff();
1365 
1366 	return ret;
1367 }
1368 
1369 /* Enable FPU for guest and restore context */
1370 void kvm_own_fpu(struct kvm_vcpu *vcpu)
1371 {
1372 	struct mips_coproc *cop0 = &vcpu->arch.cop0;
1373 	unsigned int sr, cfg5;
1374 
1375 	preempt_disable();
1376 
1377 	sr = kvm_read_c0_guest_status(cop0);
1378 
1379 	/*
1380 	 * If MSA state is already live, it is undefined how it interacts with
1381 	 * FR=0 FPU state, and we don't want to hit reserved instruction
1382 	 * exceptions trying to save the MSA state later when CU=1 && FR=1, so
1383 	 * play it safe and save it first.
1384 	 */
1385 	if (cpu_has_msa && sr & ST0_CU1 && !(sr & ST0_FR) &&
1386 	    vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA)
1387 		kvm_lose_fpu(vcpu);
1388 
1389 	/*
1390 	 * Enable FPU for guest
1391 	 * We set FR and FRE according to guest context
1392 	 */
1393 	change_c0_status(ST0_CU1 | ST0_FR, sr);
1394 	if (cpu_has_fre) {
1395 		cfg5 = kvm_read_c0_guest_config5(cop0);
1396 		change_c0_config5(MIPS_CONF5_FRE, cfg5);
1397 	}
1398 	enable_fpu_hazard();
1399 
1400 	/* If guest FPU state not active, restore it now */
1401 	if (!(vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU)) {
1402 		__kvm_restore_fpu(&vcpu->arch);
1403 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1404 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_FPU);
1405 	} else {
1406 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_FPU);
1407 	}
1408 
1409 	preempt_enable();
1410 }
1411 
1412 #ifdef CONFIG_CPU_HAS_MSA
1413 /* Enable MSA for guest and restore context */
1414 void kvm_own_msa(struct kvm_vcpu *vcpu)
1415 {
1416 	struct mips_coproc *cop0 = &vcpu->arch.cop0;
1417 	unsigned int sr, cfg5;
1418 
1419 	preempt_disable();
1420 
1421 	/*
1422 	 * Enable FPU if enabled in guest, since we're restoring FPU context
1423 	 * anyway. We set FR and FRE according to guest context.
1424 	 */
1425 	if (kvm_mips_guest_has_fpu(&vcpu->arch)) {
1426 		sr = kvm_read_c0_guest_status(cop0);
1427 
1428 		/*
1429 		 * If FR=0 FPU state is already live, it is undefined how it
1430 		 * interacts with MSA state, so play it safe and save it first.
1431 		 */
1432 		if (!(sr & ST0_FR) &&
1433 		    (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU |
1434 				KVM_MIPS_AUX_MSA)) == KVM_MIPS_AUX_FPU)
1435 			kvm_lose_fpu(vcpu);
1436 
1437 		change_c0_status(ST0_CU1 | ST0_FR, sr);
1438 		if (sr & ST0_CU1 && cpu_has_fre) {
1439 			cfg5 = kvm_read_c0_guest_config5(cop0);
1440 			change_c0_config5(MIPS_CONF5_FRE, cfg5);
1441 		}
1442 	}
1443 
1444 	/* Enable MSA for guest */
1445 	set_c0_config5(MIPS_CONF5_MSAEN);
1446 	enable_fpu_hazard();
1447 
1448 	switch (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA)) {
1449 	case KVM_MIPS_AUX_FPU:
1450 		/*
1451 		 * Guest FPU state already loaded, only restore upper MSA state
1452 		 */
1453 		__kvm_restore_msa_upper(&vcpu->arch);
1454 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1455 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_MSA);
1456 		break;
1457 	case 0:
1458 		/* Neither FPU or MSA already active, restore full MSA state */
1459 		__kvm_restore_msa(&vcpu->arch);
1460 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1461 		if (kvm_mips_guest_has_fpu(&vcpu->arch))
1462 			vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1463 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE,
1464 			      KVM_TRACE_AUX_FPU_MSA);
1465 		break;
1466 	default:
1467 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_MSA);
1468 		break;
1469 	}
1470 
1471 	preempt_enable();
1472 }
1473 #endif
1474 
1475 /* Drop FPU & MSA without saving it */
1476 void kvm_drop_fpu(struct kvm_vcpu *vcpu)
1477 {
1478 	preempt_disable();
1479 	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1480 		disable_msa();
1481 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_MSA);
1482 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_MSA;
1483 	}
1484 	if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1485 		clear_c0_status(ST0_CU1 | ST0_FR);
1486 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_FPU);
1487 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1488 	}
1489 	preempt_enable();
1490 }
1491 
1492 /* Save and disable FPU & MSA */
1493 void kvm_lose_fpu(struct kvm_vcpu *vcpu)
1494 {
1495 	/*
1496 	 * With T&E, FPU & MSA get disabled in root context (hardware) when it
1497 	 * is disabled in guest context (software), but the register state in
1498 	 * the hardware may still be in use.
1499 	 * This is why we explicitly re-enable the hardware before saving.
1500 	 */
1501 
1502 	preempt_disable();
1503 	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1504 		__kvm_save_msa(&vcpu->arch);
1505 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU_MSA);
1506 
1507 		/* Disable MSA & FPU */
1508 		disable_msa();
1509 		if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1510 			clear_c0_status(ST0_CU1 | ST0_FR);
1511 			disable_fpu_hazard();
1512 		}
1513 		vcpu->arch.aux_inuse &= ~(KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA);
1514 	} else if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1515 		__kvm_save_fpu(&vcpu->arch);
1516 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1517 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU);
1518 
1519 		/* Disable FPU */
1520 		clear_c0_status(ST0_CU1 | ST0_FR);
1521 		disable_fpu_hazard();
1522 	}
1523 	preempt_enable();
1524 }
1525 
1526 /*
1527  * Step over a specific ctc1 to FCSR and a specific ctcmsa to MSACSR which are
1528  * used to restore guest FCSR/MSACSR state and may trigger a "harmless" FP/MSAFP
1529  * exception if cause bits are set in the value being written.
1530  */
1531 static int kvm_mips_csr_die_notify(struct notifier_block *self,
1532 				   unsigned long cmd, void *ptr)
1533 {
1534 	struct die_args *args = (struct die_args *)ptr;
1535 	struct pt_regs *regs = args->regs;
1536 	unsigned long pc;
1537 
1538 	/* Only interested in FPE and MSAFPE */
1539 	if (cmd != DIE_FP && cmd != DIE_MSAFP)
1540 		return NOTIFY_DONE;
1541 
1542 	/* Return immediately if guest context isn't active */
1543 	if (!(current->flags & PF_VCPU))
1544 		return NOTIFY_DONE;
1545 
1546 	/* Should never get here from user mode */
1547 	BUG_ON(user_mode(regs));
1548 
1549 	pc = instruction_pointer(regs);
1550 	switch (cmd) {
1551 	case DIE_FP:
1552 		/* match 2nd instruction in __kvm_restore_fcsr */
1553 		if (pc != (unsigned long)&__kvm_restore_fcsr + 4)
1554 			return NOTIFY_DONE;
1555 		break;
1556 	case DIE_MSAFP:
1557 		/* match 2nd/3rd instruction in __kvm_restore_msacsr */
1558 		if (!cpu_has_msa ||
1559 		    pc < (unsigned long)&__kvm_restore_msacsr + 4 ||
1560 		    pc > (unsigned long)&__kvm_restore_msacsr + 8)
1561 			return NOTIFY_DONE;
1562 		break;
1563 	}
1564 
1565 	/* Move PC forward a little and continue executing */
1566 	instruction_pointer(regs) += 4;
1567 
1568 	return NOTIFY_STOP;
1569 }
1570 
1571 static struct notifier_block kvm_mips_csr_die_notifier = {
1572 	.notifier_call = kvm_mips_csr_die_notify,
1573 };
1574 
1575 static u32 kvm_default_priority_to_irq[MIPS_EXC_MAX] = {
1576 	[MIPS_EXC_INT_TIMER] = C_IRQ5,
1577 	[MIPS_EXC_INT_IO_1]  = C_IRQ0,
1578 	[MIPS_EXC_INT_IPI_1] = C_IRQ1,
1579 	[MIPS_EXC_INT_IPI_2] = C_IRQ2,
1580 };
1581 
1582 static u32 kvm_loongson3_priority_to_irq[MIPS_EXC_MAX] = {
1583 	[MIPS_EXC_INT_TIMER] = C_IRQ5,
1584 	[MIPS_EXC_INT_IO_1]  = C_IRQ0,
1585 	[MIPS_EXC_INT_IO_2]  = C_IRQ1,
1586 	[MIPS_EXC_INT_IPI_1] = C_IRQ4,
1587 };
1588 
1589 u32 *kvm_priority_to_irq = kvm_default_priority_to_irq;
1590 
1591 u32 kvm_irq_to_priority(u32 irq)
1592 {
1593 	int i;
1594 
1595 	for (i = MIPS_EXC_INT_TIMER; i < MIPS_EXC_MAX; i++) {
1596 		if (kvm_priority_to_irq[i] == (1 << (irq + 8)))
1597 			return i;
1598 	}
1599 
1600 	return MIPS_EXC_MAX;
1601 }
1602 
1603 static int __init kvm_mips_init(void)
1604 {
1605 	int ret;
1606 
1607 	if (cpu_has_mmid) {
1608 		pr_warn("KVM does not yet support MMIDs. KVM Disabled\n");
1609 		return -EOPNOTSUPP;
1610 	}
1611 
1612 	ret = kvm_mips_entry_setup();
1613 	if (ret)
1614 		return ret;
1615 
1616 	ret = kvm_mips_emulation_init();
1617 	if (ret)
1618 		return ret;
1619 
1620 
1621 	if (boot_cpu_type() == CPU_LOONGSON64)
1622 		kvm_priority_to_irq = kvm_loongson3_priority_to_irq;
1623 
1624 	register_die_notifier(&kvm_mips_csr_die_notifier);
1625 
1626 	ret = kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
1627 	if (ret) {
1628 		unregister_die_notifier(&kvm_mips_csr_die_notifier);
1629 		return ret;
1630 	}
1631 	return 0;
1632 }
1633 
1634 static void __exit kvm_mips_exit(void)
1635 {
1636 	kvm_exit();
1637 
1638 	unregister_die_notifier(&kvm_mips_csr_die_notifier);
1639 }
1640 
1641 module_init(kvm_mips_init);
1642 module_exit(kvm_mips_exit);
1643 
1644 EXPORT_TRACEPOINT_SYMBOL(kvm_exit);
1645