xref: /openbmc/linux/arch/mips/kvm/mips.c (revision 36de991e)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * KVM/MIPS: MIPS specific KVM APIs
7  *
8  * Copyright (C) 2012  MIPS Technologies, Inc.  All rights reserved.
9  * Authors: Sanjay Lal <sanjayl@kymasys.com>
10  */
11 
12 #include <linux/bitops.h>
13 #include <linux/errno.h>
14 #include <linux/err.h>
15 #include <linux/kdebug.h>
16 #include <linux/module.h>
17 #include <linux/uaccess.h>
18 #include <linux/vmalloc.h>
19 #include <linux/sched/signal.h>
20 #include <linux/fs.h>
21 #include <linux/memblock.h>
22 #include <linux/pgtable.h>
23 
24 #include <asm/fpu.h>
25 #include <asm/page.h>
26 #include <asm/cacheflush.h>
27 #include <asm/mmu_context.h>
28 #include <asm/pgalloc.h>
29 
30 #include <linux/kvm_host.h>
31 
32 #include "interrupt.h"
33 
34 #define CREATE_TRACE_POINTS
35 #include "trace.h"
36 
37 #ifndef VECTORSPACING
38 #define VECTORSPACING 0x100	/* for EI/VI mode */
39 #endif
40 
41 const struct _kvm_stats_desc kvm_vm_stats_desc[] = {
42 	KVM_GENERIC_VM_STATS()
43 };
44 
45 const struct kvm_stats_header kvm_vm_stats_header = {
46 	.name_size = KVM_STATS_NAME_SIZE,
47 	.num_desc = ARRAY_SIZE(kvm_vm_stats_desc),
48 	.id_offset = sizeof(struct kvm_stats_header),
49 	.desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE,
50 	.data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE +
51 		       sizeof(kvm_vm_stats_desc),
52 };
53 
54 const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = {
55 	KVM_GENERIC_VCPU_STATS(),
56 	STATS_DESC_COUNTER(VCPU, wait_exits),
57 	STATS_DESC_COUNTER(VCPU, cache_exits),
58 	STATS_DESC_COUNTER(VCPU, signal_exits),
59 	STATS_DESC_COUNTER(VCPU, int_exits),
60 	STATS_DESC_COUNTER(VCPU, cop_unusable_exits),
61 	STATS_DESC_COUNTER(VCPU, tlbmod_exits),
62 	STATS_DESC_COUNTER(VCPU, tlbmiss_ld_exits),
63 	STATS_DESC_COUNTER(VCPU, tlbmiss_st_exits),
64 	STATS_DESC_COUNTER(VCPU, addrerr_st_exits),
65 	STATS_DESC_COUNTER(VCPU, addrerr_ld_exits),
66 	STATS_DESC_COUNTER(VCPU, syscall_exits),
67 	STATS_DESC_COUNTER(VCPU, resvd_inst_exits),
68 	STATS_DESC_COUNTER(VCPU, break_inst_exits),
69 	STATS_DESC_COUNTER(VCPU, trap_inst_exits),
70 	STATS_DESC_COUNTER(VCPU, msa_fpe_exits),
71 	STATS_DESC_COUNTER(VCPU, fpe_exits),
72 	STATS_DESC_COUNTER(VCPU, msa_disabled_exits),
73 	STATS_DESC_COUNTER(VCPU, flush_dcache_exits),
74 	STATS_DESC_COUNTER(VCPU, vz_gpsi_exits),
75 	STATS_DESC_COUNTER(VCPU, vz_gsfc_exits),
76 	STATS_DESC_COUNTER(VCPU, vz_hc_exits),
77 	STATS_DESC_COUNTER(VCPU, vz_grr_exits),
78 	STATS_DESC_COUNTER(VCPU, vz_gva_exits),
79 	STATS_DESC_COUNTER(VCPU, vz_ghfc_exits),
80 	STATS_DESC_COUNTER(VCPU, vz_gpa_exits),
81 	STATS_DESC_COUNTER(VCPU, vz_resvd_exits),
82 #ifdef CONFIG_CPU_LOONGSON64
83 	STATS_DESC_COUNTER(VCPU, vz_cpucfg_exits),
84 #endif
85 };
86 
87 const struct kvm_stats_header kvm_vcpu_stats_header = {
88 	.name_size = KVM_STATS_NAME_SIZE,
89 	.num_desc = ARRAY_SIZE(kvm_vcpu_stats_desc),
90 	.id_offset = sizeof(struct kvm_stats_header),
91 	.desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE,
92 	.data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE +
93 		       sizeof(kvm_vcpu_stats_desc),
94 };
95 
96 bool kvm_trace_guest_mode_change;
97 
98 int kvm_guest_mode_change_trace_reg(void)
99 {
100 	kvm_trace_guest_mode_change = true;
101 	return 0;
102 }
103 
104 void kvm_guest_mode_change_trace_unreg(void)
105 {
106 	kvm_trace_guest_mode_change = false;
107 }
108 
109 /*
110  * XXXKYMA: We are simulatoring a processor that has the WII bit set in
111  * Config7, so we are "runnable" if interrupts are pending
112  */
113 int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
114 {
115 	return !!(vcpu->arch.pending_exceptions);
116 }
117 
118 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
119 {
120 	return false;
121 }
122 
123 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
124 {
125 	return 1;
126 }
127 
128 int kvm_arch_hardware_enable(void)
129 {
130 	return kvm_mips_callbacks->hardware_enable();
131 }
132 
133 void kvm_arch_hardware_disable(void)
134 {
135 	kvm_mips_callbacks->hardware_disable();
136 }
137 
138 int kvm_arch_hardware_setup(void *opaque)
139 {
140 	return 0;
141 }
142 
143 int kvm_arch_check_processor_compat(void *opaque)
144 {
145 	return 0;
146 }
147 
148 extern void kvm_init_loongson_ipi(struct kvm *kvm);
149 
150 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
151 {
152 	switch (type) {
153 	case KVM_VM_MIPS_AUTO:
154 		break;
155 	case KVM_VM_MIPS_VZ:
156 		break;
157 	default:
158 		/* Unsupported KVM type */
159 		return -EINVAL;
160 	}
161 
162 	/* Allocate page table to map GPA -> RPA */
163 	kvm->arch.gpa_mm.pgd = kvm_pgd_alloc();
164 	if (!kvm->arch.gpa_mm.pgd)
165 		return -ENOMEM;
166 
167 #ifdef CONFIG_CPU_LOONGSON64
168 	kvm_init_loongson_ipi(kvm);
169 #endif
170 
171 	return 0;
172 }
173 
174 void kvm_mips_free_vcpus(struct kvm *kvm)
175 {
176 	unsigned int i;
177 	struct kvm_vcpu *vcpu;
178 
179 	kvm_for_each_vcpu(i, vcpu, kvm) {
180 		kvm_vcpu_destroy(vcpu);
181 	}
182 
183 	mutex_lock(&kvm->lock);
184 
185 	for (i = 0; i < atomic_read(&kvm->online_vcpus); i++)
186 		kvm->vcpus[i] = NULL;
187 
188 	atomic_set(&kvm->online_vcpus, 0);
189 
190 	mutex_unlock(&kvm->lock);
191 }
192 
193 static void kvm_mips_free_gpa_pt(struct kvm *kvm)
194 {
195 	/* It should always be safe to remove after flushing the whole range */
196 	WARN_ON(!kvm_mips_flush_gpa_pt(kvm, 0, ~0));
197 	pgd_free(NULL, kvm->arch.gpa_mm.pgd);
198 }
199 
200 void kvm_arch_destroy_vm(struct kvm *kvm)
201 {
202 	kvm_mips_free_vcpus(kvm);
203 	kvm_mips_free_gpa_pt(kvm);
204 }
205 
206 long kvm_arch_dev_ioctl(struct file *filp, unsigned int ioctl,
207 			unsigned long arg)
208 {
209 	return -ENOIOCTLCMD;
210 }
211 
212 void kvm_arch_flush_shadow_all(struct kvm *kvm)
213 {
214 	/* Flush whole GPA */
215 	kvm_mips_flush_gpa_pt(kvm, 0, ~0);
216 	kvm_flush_remote_tlbs(kvm);
217 }
218 
219 void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
220 				   struct kvm_memory_slot *slot)
221 {
222 	/*
223 	 * The slot has been made invalid (ready for moving or deletion), so we
224 	 * need to ensure that it can no longer be accessed by any guest VCPUs.
225 	 */
226 
227 	spin_lock(&kvm->mmu_lock);
228 	/* Flush slot from GPA */
229 	kvm_mips_flush_gpa_pt(kvm, slot->base_gfn,
230 			      slot->base_gfn + slot->npages - 1);
231 	kvm_arch_flush_remote_tlbs_memslot(kvm, slot);
232 	spin_unlock(&kvm->mmu_lock);
233 }
234 
235 int kvm_arch_prepare_memory_region(struct kvm *kvm,
236 				   struct kvm_memory_slot *memslot,
237 				   const struct kvm_userspace_memory_region *mem,
238 				   enum kvm_mr_change change)
239 {
240 	return 0;
241 }
242 
243 void kvm_arch_commit_memory_region(struct kvm *kvm,
244 				   const struct kvm_userspace_memory_region *mem,
245 				   struct kvm_memory_slot *old,
246 				   const struct kvm_memory_slot *new,
247 				   enum kvm_mr_change change)
248 {
249 	int needs_flush;
250 
251 	kvm_debug("%s: kvm: %p slot: %d, GPA: %llx, size: %llx, QVA: %llx\n",
252 		  __func__, kvm, mem->slot, mem->guest_phys_addr,
253 		  mem->memory_size, mem->userspace_addr);
254 
255 	/*
256 	 * If dirty page logging is enabled, write protect all pages in the slot
257 	 * ready for dirty logging.
258 	 *
259 	 * There is no need to do this in any of the following cases:
260 	 * CREATE:	No dirty mappings will already exist.
261 	 * MOVE/DELETE:	The old mappings will already have been cleaned up by
262 	 *		kvm_arch_flush_shadow_memslot()
263 	 */
264 	if (change == KVM_MR_FLAGS_ONLY &&
265 	    (!(old->flags & KVM_MEM_LOG_DIRTY_PAGES) &&
266 	     new->flags & KVM_MEM_LOG_DIRTY_PAGES)) {
267 		spin_lock(&kvm->mmu_lock);
268 		/* Write protect GPA page table entries */
269 		needs_flush = kvm_mips_mkclean_gpa_pt(kvm, new->base_gfn,
270 					new->base_gfn + new->npages - 1);
271 		if (needs_flush)
272 			kvm_arch_flush_remote_tlbs_memslot(kvm, new);
273 		spin_unlock(&kvm->mmu_lock);
274 	}
275 }
276 
277 static inline void dump_handler(const char *symbol, void *start, void *end)
278 {
279 	u32 *p;
280 
281 	pr_debug("LEAF(%s)\n", symbol);
282 
283 	pr_debug("\t.set push\n");
284 	pr_debug("\t.set noreorder\n");
285 
286 	for (p = start; p < (u32 *)end; ++p)
287 		pr_debug("\t.word\t0x%08x\t\t# %p\n", *p, p);
288 
289 	pr_debug("\t.set\tpop\n");
290 
291 	pr_debug("\tEND(%s)\n", symbol);
292 }
293 
294 /* low level hrtimer wake routine */
295 static enum hrtimer_restart kvm_mips_comparecount_wakeup(struct hrtimer *timer)
296 {
297 	struct kvm_vcpu *vcpu;
298 
299 	vcpu = container_of(timer, struct kvm_vcpu, arch.comparecount_timer);
300 
301 	kvm_mips_callbacks->queue_timer_int(vcpu);
302 
303 	vcpu->arch.wait = 0;
304 	rcuwait_wake_up(&vcpu->wait);
305 
306 	return kvm_mips_count_timeout(vcpu);
307 }
308 
309 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
310 {
311 	return 0;
312 }
313 
314 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
315 {
316 	int err, size;
317 	void *gebase, *p, *handler, *refill_start, *refill_end;
318 	int i;
319 
320 	kvm_debug("kvm @ %p: create cpu %d at %p\n",
321 		  vcpu->kvm, vcpu->vcpu_id, vcpu);
322 
323 	err = kvm_mips_callbacks->vcpu_init(vcpu);
324 	if (err)
325 		return err;
326 
327 	hrtimer_init(&vcpu->arch.comparecount_timer, CLOCK_MONOTONIC,
328 		     HRTIMER_MODE_REL);
329 	vcpu->arch.comparecount_timer.function = kvm_mips_comparecount_wakeup;
330 
331 	/*
332 	 * Allocate space for host mode exception handlers that handle
333 	 * guest mode exits
334 	 */
335 	if (cpu_has_veic || cpu_has_vint)
336 		size = 0x200 + VECTORSPACING * 64;
337 	else
338 		size = 0x4000;
339 
340 	gebase = kzalloc(ALIGN(size, PAGE_SIZE), GFP_KERNEL);
341 
342 	if (!gebase) {
343 		err = -ENOMEM;
344 		goto out_uninit_vcpu;
345 	}
346 	kvm_debug("Allocated %d bytes for KVM Exception Handlers @ %p\n",
347 		  ALIGN(size, PAGE_SIZE), gebase);
348 
349 	/*
350 	 * Check new ebase actually fits in CP0_EBase. The lack of a write gate
351 	 * limits us to the low 512MB of physical address space. If the memory
352 	 * we allocate is out of range, just give up now.
353 	 */
354 	if (!cpu_has_ebase_wg && virt_to_phys(gebase) >= 0x20000000) {
355 		kvm_err("CP0_EBase.WG required for guest exception base %pK\n",
356 			gebase);
357 		err = -ENOMEM;
358 		goto out_free_gebase;
359 	}
360 
361 	/* Save new ebase */
362 	vcpu->arch.guest_ebase = gebase;
363 
364 	/* Build guest exception vectors dynamically in unmapped memory */
365 	handler = gebase + 0x2000;
366 
367 	/* TLB refill (or XTLB refill on 64-bit VZ where KX=1) */
368 	refill_start = gebase;
369 	if (IS_ENABLED(CONFIG_64BIT))
370 		refill_start += 0x080;
371 	refill_end = kvm_mips_build_tlb_refill_exception(refill_start, handler);
372 
373 	/* General Exception Entry point */
374 	kvm_mips_build_exception(gebase + 0x180, handler);
375 
376 	/* For vectored interrupts poke the exception code @ all offsets 0-7 */
377 	for (i = 0; i < 8; i++) {
378 		kvm_debug("L1 Vectored handler @ %p\n",
379 			  gebase + 0x200 + (i * VECTORSPACING));
380 		kvm_mips_build_exception(gebase + 0x200 + i * VECTORSPACING,
381 					 handler);
382 	}
383 
384 	/* General exit handler */
385 	p = handler;
386 	p = kvm_mips_build_exit(p);
387 
388 	/* Guest entry routine */
389 	vcpu->arch.vcpu_run = p;
390 	p = kvm_mips_build_vcpu_run(p);
391 
392 	/* Dump the generated code */
393 	pr_debug("#include <asm/asm.h>\n");
394 	pr_debug("#include <asm/regdef.h>\n");
395 	pr_debug("\n");
396 	dump_handler("kvm_vcpu_run", vcpu->arch.vcpu_run, p);
397 	dump_handler("kvm_tlb_refill", refill_start, refill_end);
398 	dump_handler("kvm_gen_exc", gebase + 0x180, gebase + 0x200);
399 	dump_handler("kvm_exit", gebase + 0x2000, vcpu->arch.vcpu_run);
400 
401 	/* Invalidate the icache for these ranges */
402 	flush_icache_range((unsigned long)gebase,
403 			   (unsigned long)gebase + ALIGN(size, PAGE_SIZE));
404 
405 	/* Init */
406 	vcpu->arch.last_sched_cpu = -1;
407 	vcpu->arch.last_exec_cpu = -1;
408 
409 	/* Initial guest state */
410 	err = kvm_mips_callbacks->vcpu_setup(vcpu);
411 	if (err)
412 		goto out_free_gebase;
413 
414 	return 0;
415 
416 out_free_gebase:
417 	kfree(gebase);
418 out_uninit_vcpu:
419 	kvm_mips_callbacks->vcpu_uninit(vcpu);
420 	return err;
421 }
422 
423 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
424 {
425 	hrtimer_cancel(&vcpu->arch.comparecount_timer);
426 
427 	kvm_mips_dump_stats(vcpu);
428 
429 	kvm_mmu_free_memory_caches(vcpu);
430 	kfree(vcpu->arch.guest_ebase);
431 
432 	kvm_mips_callbacks->vcpu_uninit(vcpu);
433 }
434 
435 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
436 					struct kvm_guest_debug *dbg)
437 {
438 	return -ENOIOCTLCMD;
439 }
440 
441 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
442 {
443 	int r = -EINTR;
444 
445 	vcpu_load(vcpu);
446 
447 	kvm_sigset_activate(vcpu);
448 
449 	if (vcpu->mmio_needed) {
450 		if (!vcpu->mmio_is_write)
451 			kvm_mips_complete_mmio_load(vcpu);
452 		vcpu->mmio_needed = 0;
453 	}
454 
455 	if (vcpu->run->immediate_exit)
456 		goto out;
457 
458 	lose_fpu(1);
459 
460 	local_irq_disable();
461 	guest_enter_irqoff();
462 	trace_kvm_enter(vcpu);
463 
464 	/*
465 	 * Make sure the read of VCPU requests in vcpu_run() callback is not
466 	 * reordered ahead of the write to vcpu->mode, or we could miss a TLB
467 	 * flush request while the requester sees the VCPU as outside of guest
468 	 * mode and not needing an IPI.
469 	 */
470 	smp_store_mb(vcpu->mode, IN_GUEST_MODE);
471 
472 	r = kvm_mips_callbacks->vcpu_run(vcpu);
473 
474 	trace_kvm_out(vcpu);
475 	guest_exit_irqoff();
476 	local_irq_enable();
477 
478 out:
479 	kvm_sigset_deactivate(vcpu);
480 
481 	vcpu_put(vcpu);
482 	return r;
483 }
484 
485 int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
486 			     struct kvm_mips_interrupt *irq)
487 {
488 	int intr = (int)irq->irq;
489 	struct kvm_vcpu *dvcpu = NULL;
490 
491 	if (intr == kvm_priority_to_irq[MIPS_EXC_INT_IPI_1] ||
492 	    intr == kvm_priority_to_irq[MIPS_EXC_INT_IPI_2] ||
493 	    intr == (-kvm_priority_to_irq[MIPS_EXC_INT_IPI_1]) ||
494 	    intr == (-kvm_priority_to_irq[MIPS_EXC_INT_IPI_2]))
495 		kvm_debug("%s: CPU: %d, INTR: %d\n", __func__, irq->cpu,
496 			  (int)intr);
497 
498 	if (irq->cpu == -1)
499 		dvcpu = vcpu;
500 	else
501 		dvcpu = vcpu->kvm->vcpus[irq->cpu];
502 
503 	if (intr == 2 || intr == 3 || intr == 4 || intr == 6) {
504 		kvm_mips_callbacks->queue_io_int(dvcpu, irq);
505 
506 	} else if (intr == -2 || intr == -3 || intr == -4 || intr == -6) {
507 		kvm_mips_callbacks->dequeue_io_int(dvcpu, irq);
508 	} else {
509 		kvm_err("%s: invalid interrupt ioctl (%d:%d)\n", __func__,
510 			irq->cpu, irq->irq);
511 		return -EINVAL;
512 	}
513 
514 	dvcpu->arch.wait = 0;
515 
516 	rcuwait_wake_up(&dvcpu->wait);
517 
518 	return 0;
519 }
520 
521 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
522 				    struct kvm_mp_state *mp_state)
523 {
524 	return -ENOIOCTLCMD;
525 }
526 
527 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
528 				    struct kvm_mp_state *mp_state)
529 {
530 	return -ENOIOCTLCMD;
531 }
532 
533 static u64 kvm_mips_get_one_regs[] = {
534 	KVM_REG_MIPS_R0,
535 	KVM_REG_MIPS_R1,
536 	KVM_REG_MIPS_R2,
537 	KVM_REG_MIPS_R3,
538 	KVM_REG_MIPS_R4,
539 	KVM_REG_MIPS_R5,
540 	KVM_REG_MIPS_R6,
541 	KVM_REG_MIPS_R7,
542 	KVM_REG_MIPS_R8,
543 	KVM_REG_MIPS_R9,
544 	KVM_REG_MIPS_R10,
545 	KVM_REG_MIPS_R11,
546 	KVM_REG_MIPS_R12,
547 	KVM_REG_MIPS_R13,
548 	KVM_REG_MIPS_R14,
549 	KVM_REG_MIPS_R15,
550 	KVM_REG_MIPS_R16,
551 	KVM_REG_MIPS_R17,
552 	KVM_REG_MIPS_R18,
553 	KVM_REG_MIPS_R19,
554 	KVM_REG_MIPS_R20,
555 	KVM_REG_MIPS_R21,
556 	KVM_REG_MIPS_R22,
557 	KVM_REG_MIPS_R23,
558 	KVM_REG_MIPS_R24,
559 	KVM_REG_MIPS_R25,
560 	KVM_REG_MIPS_R26,
561 	KVM_REG_MIPS_R27,
562 	KVM_REG_MIPS_R28,
563 	KVM_REG_MIPS_R29,
564 	KVM_REG_MIPS_R30,
565 	KVM_REG_MIPS_R31,
566 
567 #ifndef CONFIG_CPU_MIPSR6
568 	KVM_REG_MIPS_HI,
569 	KVM_REG_MIPS_LO,
570 #endif
571 	KVM_REG_MIPS_PC,
572 };
573 
574 static u64 kvm_mips_get_one_regs_fpu[] = {
575 	KVM_REG_MIPS_FCR_IR,
576 	KVM_REG_MIPS_FCR_CSR,
577 };
578 
579 static u64 kvm_mips_get_one_regs_msa[] = {
580 	KVM_REG_MIPS_MSA_IR,
581 	KVM_REG_MIPS_MSA_CSR,
582 };
583 
584 static unsigned long kvm_mips_num_regs(struct kvm_vcpu *vcpu)
585 {
586 	unsigned long ret;
587 
588 	ret = ARRAY_SIZE(kvm_mips_get_one_regs);
589 	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
590 		ret += ARRAY_SIZE(kvm_mips_get_one_regs_fpu) + 48;
591 		/* odd doubles */
592 		if (boot_cpu_data.fpu_id & MIPS_FPIR_F64)
593 			ret += 16;
594 	}
595 	if (kvm_mips_guest_can_have_msa(&vcpu->arch))
596 		ret += ARRAY_SIZE(kvm_mips_get_one_regs_msa) + 32;
597 	ret += kvm_mips_callbacks->num_regs(vcpu);
598 
599 	return ret;
600 }
601 
602 static int kvm_mips_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices)
603 {
604 	u64 index;
605 	unsigned int i;
606 
607 	if (copy_to_user(indices, kvm_mips_get_one_regs,
608 			 sizeof(kvm_mips_get_one_regs)))
609 		return -EFAULT;
610 	indices += ARRAY_SIZE(kvm_mips_get_one_regs);
611 
612 	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
613 		if (copy_to_user(indices, kvm_mips_get_one_regs_fpu,
614 				 sizeof(kvm_mips_get_one_regs_fpu)))
615 			return -EFAULT;
616 		indices += ARRAY_SIZE(kvm_mips_get_one_regs_fpu);
617 
618 		for (i = 0; i < 32; ++i) {
619 			index = KVM_REG_MIPS_FPR_32(i);
620 			if (copy_to_user(indices, &index, sizeof(index)))
621 				return -EFAULT;
622 			++indices;
623 
624 			/* skip odd doubles if no F64 */
625 			if (i & 1 && !(boot_cpu_data.fpu_id & MIPS_FPIR_F64))
626 				continue;
627 
628 			index = KVM_REG_MIPS_FPR_64(i);
629 			if (copy_to_user(indices, &index, sizeof(index)))
630 				return -EFAULT;
631 			++indices;
632 		}
633 	}
634 
635 	if (kvm_mips_guest_can_have_msa(&vcpu->arch)) {
636 		if (copy_to_user(indices, kvm_mips_get_one_regs_msa,
637 				 sizeof(kvm_mips_get_one_regs_msa)))
638 			return -EFAULT;
639 		indices += ARRAY_SIZE(kvm_mips_get_one_regs_msa);
640 
641 		for (i = 0; i < 32; ++i) {
642 			index = KVM_REG_MIPS_VEC_128(i);
643 			if (copy_to_user(indices, &index, sizeof(index)))
644 				return -EFAULT;
645 			++indices;
646 		}
647 	}
648 
649 	return kvm_mips_callbacks->copy_reg_indices(vcpu, indices);
650 }
651 
652 static int kvm_mips_get_reg(struct kvm_vcpu *vcpu,
653 			    const struct kvm_one_reg *reg)
654 {
655 	struct mips_coproc *cop0 = vcpu->arch.cop0;
656 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
657 	int ret;
658 	s64 v;
659 	s64 vs[2];
660 	unsigned int idx;
661 
662 	switch (reg->id) {
663 	/* General purpose registers */
664 	case KVM_REG_MIPS_R0 ... KVM_REG_MIPS_R31:
665 		v = (long)vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0];
666 		break;
667 #ifndef CONFIG_CPU_MIPSR6
668 	case KVM_REG_MIPS_HI:
669 		v = (long)vcpu->arch.hi;
670 		break;
671 	case KVM_REG_MIPS_LO:
672 		v = (long)vcpu->arch.lo;
673 		break;
674 #endif
675 	case KVM_REG_MIPS_PC:
676 		v = (long)vcpu->arch.pc;
677 		break;
678 
679 	/* Floating point registers */
680 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
681 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
682 			return -EINVAL;
683 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
684 		/* Odd singles in top of even double when FR=0 */
685 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
686 			v = get_fpr32(&fpu->fpr[idx], 0);
687 		else
688 			v = get_fpr32(&fpu->fpr[idx & ~1], idx & 1);
689 		break;
690 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
691 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
692 			return -EINVAL;
693 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
694 		/* Can't access odd doubles in FR=0 mode */
695 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
696 			return -EINVAL;
697 		v = get_fpr64(&fpu->fpr[idx], 0);
698 		break;
699 	case KVM_REG_MIPS_FCR_IR:
700 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
701 			return -EINVAL;
702 		v = boot_cpu_data.fpu_id;
703 		break;
704 	case KVM_REG_MIPS_FCR_CSR:
705 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
706 			return -EINVAL;
707 		v = fpu->fcr31;
708 		break;
709 
710 	/* MIPS SIMD Architecture (MSA) registers */
711 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
712 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
713 			return -EINVAL;
714 		/* Can't access MSA registers in FR=0 mode */
715 		if (!(kvm_read_c0_guest_status(cop0) & ST0_FR))
716 			return -EINVAL;
717 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
718 #ifdef CONFIG_CPU_LITTLE_ENDIAN
719 		/* least significant byte first */
720 		vs[0] = get_fpr64(&fpu->fpr[idx], 0);
721 		vs[1] = get_fpr64(&fpu->fpr[idx], 1);
722 #else
723 		/* most significant byte first */
724 		vs[0] = get_fpr64(&fpu->fpr[idx], 1);
725 		vs[1] = get_fpr64(&fpu->fpr[idx], 0);
726 #endif
727 		break;
728 	case KVM_REG_MIPS_MSA_IR:
729 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
730 			return -EINVAL;
731 		v = boot_cpu_data.msa_id;
732 		break;
733 	case KVM_REG_MIPS_MSA_CSR:
734 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
735 			return -EINVAL;
736 		v = fpu->msacsr;
737 		break;
738 
739 	/* registers to be handled specially */
740 	default:
741 		ret = kvm_mips_callbacks->get_one_reg(vcpu, reg, &v);
742 		if (ret)
743 			return ret;
744 		break;
745 	}
746 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
747 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
748 
749 		return put_user(v, uaddr64);
750 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
751 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
752 		u32 v32 = (u32)v;
753 
754 		return put_user(v32, uaddr32);
755 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
756 		void __user *uaddr = (void __user *)(long)reg->addr;
757 
758 		return copy_to_user(uaddr, vs, 16) ? -EFAULT : 0;
759 	} else {
760 		return -EINVAL;
761 	}
762 }
763 
764 static int kvm_mips_set_reg(struct kvm_vcpu *vcpu,
765 			    const struct kvm_one_reg *reg)
766 {
767 	struct mips_coproc *cop0 = vcpu->arch.cop0;
768 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
769 	s64 v;
770 	s64 vs[2];
771 	unsigned int idx;
772 
773 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
774 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
775 
776 		if (get_user(v, uaddr64) != 0)
777 			return -EFAULT;
778 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
779 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
780 		s32 v32;
781 
782 		if (get_user(v32, uaddr32) != 0)
783 			return -EFAULT;
784 		v = (s64)v32;
785 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
786 		void __user *uaddr = (void __user *)(long)reg->addr;
787 
788 		return copy_from_user(vs, uaddr, 16) ? -EFAULT : 0;
789 	} else {
790 		return -EINVAL;
791 	}
792 
793 	switch (reg->id) {
794 	/* General purpose registers */
795 	case KVM_REG_MIPS_R0:
796 		/* Silently ignore requests to set $0 */
797 		break;
798 	case KVM_REG_MIPS_R1 ... KVM_REG_MIPS_R31:
799 		vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0] = v;
800 		break;
801 #ifndef CONFIG_CPU_MIPSR6
802 	case KVM_REG_MIPS_HI:
803 		vcpu->arch.hi = v;
804 		break;
805 	case KVM_REG_MIPS_LO:
806 		vcpu->arch.lo = v;
807 		break;
808 #endif
809 	case KVM_REG_MIPS_PC:
810 		vcpu->arch.pc = v;
811 		break;
812 
813 	/* Floating point registers */
814 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
815 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
816 			return -EINVAL;
817 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
818 		/* Odd singles in top of even double when FR=0 */
819 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
820 			set_fpr32(&fpu->fpr[idx], 0, v);
821 		else
822 			set_fpr32(&fpu->fpr[idx & ~1], idx & 1, v);
823 		break;
824 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
825 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
826 			return -EINVAL;
827 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
828 		/* Can't access odd doubles in FR=0 mode */
829 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
830 			return -EINVAL;
831 		set_fpr64(&fpu->fpr[idx], 0, v);
832 		break;
833 	case KVM_REG_MIPS_FCR_IR:
834 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
835 			return -EINVAL;
836 		/* Read-only */
837 		break;
838 	case KVM_REG_MIPS_FCR_CSR:
839 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
840 			return -EINVAL;
841 		fpu->fcr31 = v;
842 		break;
843 
844 	/* MIPS SIMD Architecture (MSA) registers */
845 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
846 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
847 			return -EINVAL;
848 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
849 #ifdef CONFIG_CPU_LITTLE_ENDIAN
850 		/* least significant byte first */
851 		set_fpr64(&fpu->fpr[idx], 0, vs[0]);
852 		set_fpr64(&fpu->fpr[idx], 1, vs[1]);
853 #else
854 		/* most significant byte first */
855 		set_fpr64(&fpu->fpr[idx], 1, vs[0]);
856 		set_fpr64(&fpu->fpr[idx], 0, vs[1]);
857 #endif
858 		break;
859 	case KVM_REG_MIPS_MSA_IR:
860 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
861 			return -EINVAL;
862 		/* Read-only */
863 		break;
864 	case KVM_REG_MIPS_MSA_CSR:
865 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
866 			return -EINVAL;
867 		fpu->msacsr = v;
868 		break;
869 
870 	/* registers to be handled specially */
871 	default:
872 		return kvm_mips_callbacks->set_one_reg(vcpu, reg, v);
873 	}
874 	return 0;
875 }
876 
877 static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
878 				     struct kvm_enable_cap *cap)
879 {
880 	int r = 0;
881 
882 	if (!kvm_vm_ioctl_check_extension(vcpu->kvm, cap->cap))
883 		return -EINVAL;
884 	if (cap->flags)
885 		return -EINVAL;
886 	if (cap->args[0])
887 		return -EINVAL;
888 
889 	switch (cap->cap) {
890 	case KVM_CAP_MIPS_FPU:
891 		vcpu->arch.fpu_enabled = true;
892 		break;
893 	case KVM_CAP_MIPS_MSA:
894 		vcpu->arch.msa_enabled = true;
895 		break;
896 	default:
897 		r = -EINVAL;
898 		break;
899 	}
900 
901 	return r;
902 }
903 
904 long kvm_arch_vcpu_async_ioctl(struct file *filp, unsigned int ioctl,
905 			       unsigned long arg)
906 {
907 	struct kvm_vcpu *vcpu = filp->private_data;
908 	void __user *argp = (void __user *)arg;
909 
910 	if (ioctl == KVM_INTERRUPT) {
911 		struct kvm_mips_interrupt irq;
912 
913 		if (copy_from_user(&irq, argp, sizeof(irq)))
914 			return -EFAULT;
915 		kvm_debug("[%d] %s: irq: %d\n", vcpu->vcpu_id, __func__,
916 			  irq.irq);
917 
918 		return kvm_vcpu_ioctl_interrupt(vcpu, &irq);
919 	}
920 
921 	return -ENOIOCTLCMD;
922 }
923 
924 long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl,
925 			 unsigned long arg)
926 {
927 	struct kvm_vcpu *vcpu = filp->private_data;
928 	void __user *argp = (void __user *)arg;
929 	long r;
930 
931 	vcpu_load(vcpu);
932 
933 	switch (ioctl) {
934 	case KVM_SET_ONE_REG:
935 	case KVM_GET_ONE_REG: {
936 		struct kvm_one_reg reg;
937 
938 		r = -EFAULT;
939 		if (copy_from_user(&reg, argp, sizeof(reg)))
940 			break;
941 		if (ioctl == KVM_SET_ONE_REG)
942 			r = kvm_mips_set_reg(vcpu, &reg);
943 		else
944 			r = kvm_mips_get_reg(vcpu, &reg);
945 		break;
946 	}
947 	case KVM_GET_REG_LIST: {
948 		struct kvm_reg_list __user *user_list = argp;
949 		struct kvm_reg_list reg_list;
950 		unsigned n;
951 
952 		r = -EFAULT;
953 		if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
954 			break;
955 		n = reg_list.n;
956 		reg_list.n = kvm_mips_num_regs(vcpu);
957 		if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
958 			break;
959 		r = -E2BIG;
960 		if (n < reg_list.n)
961 			break;
962 		r = kvm_mips_copy_reg_indices(vcpu, user_list->reg);
963 		break;
964 	}
965 	case KVM_ENABLE_CAP: {
966 		struct kvm_enable_cap cap;
967 
968 		r = -EFAULT;
969 		if (copy_from_user(&cap, argp, sizeof(cap)))
970 			break;
971 		r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
972 		break;
973 	}
974 	default:
975 		r = -ENOIOCTLCMD;
976 	}
977 
978 	vcpu_put(vcpu);
979 	return r;
980 }
981 
982 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
983 {
984 
985 }
986 
987 int kvm_arch_flush_remote_tlb(struct kvm *kvm)
988 {
989 	kvm_mips_callbacks->prepare_flush_shadow(kvm);
990 	return 1;
991 }
992 
993 void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
994 					const struct kvm_memory_slot *memslot)
995 {
996 	kvm_flush_remote_tlbs(kvm);
997 }
998 
999 long kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
1000 {
1001 	long r;
1002 
1003 	switch (ioctl) {
1004 	default:
1005 		r = -ENOIOCTLCMD;
1006 	}
1007 
1008 	return r;
1009 }
1010 
1011 int kvm_arch_init(void *opaque)
1012 {
1013 	if (kvm_mips_callbacks) {
1014 		kvm_err("kvm: module already exists\n");
1015 		return -EEXIST;
1016 	}
1017 
1018 	return kvm_mips_emulation_init(&kvm_mips_callbacks);
1019 }
1020 
1021 void kvm_arch_exit(void)
1022 {
1023 	kvm_mips_callbacks = NULL;
1024 }
1025 
1026 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
1027 				  struct kvm_sregs *sregs)
1028 {
1029 	return -ENOIOCTLCMD;
1030 }
1031 
1032 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
1033 				  struct kvm_sregs *sregs)
1034 {
1035 	return -ENOIOCTLCMD;
1036 }
1037 
1038 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
1039 {
1040 }
1041 
1042 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1043 {
1044 	return -ENOIOCTLCMD;
1045 }
1046 
1047 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1048 {
1049 	return -ENOIOCTLCMD;
1050 }
1051 
1052 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
1053 {
1054 	return VM_FAULT_SIGBUS;
1055 }
1056 
1057 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
1058 {
1059 	int r;
1060 
1061 	switch (ext) {
1062 	case KVM_CAP_ONE_REG:
1063 	case KVM_CAP_ENABLE_CAP:
1064 	case KVM_CAP_READONLY_MEM:
1065 	case KVM_CAP_SYNC_MMU:
1066 	case KVM_CAP_IMMEDIATE_EXIT:
1067 		r = 1;
1068 		break;
1069 	case KVM_CAP_NR_VCPUS:
1070 		r = min_t(unsigned int, num_online_cpus(), KVM_MAX_VCPUS);
1071 		break;
1072 	case KVM_CAP_MAX_VCPUS:
1073 		r = KVM_MAX_VCPUS;
1074 		break;
1075 	case KVM_CAP_MAX_VCPU_ID:
1076 		r = KVM_MAX_VCPU_IDS;
1077 		break;
1078 	case KVM_CAP_MIPS_FPU:
1079 		/* We don't handle systems with inconsistent cpu_has_fpu */
1080 		r = !!raw_cpu_has_fpu;
1081 		break;
1082 	case KVM_CAP_MIPS_MSA:
1083 		/*
1084 		 * We don't support MSA vector partitioning yet:
1085 		 * 1) It would require explicit support which can't be tested
1086 		 *    yet due to lack of support in current hardware.
1087 		 * 2) It extends the state that would need to be saved/restored
1088 		 *    by e.g. QEMU for migration.
1089 		 *
1090 		 * When vector partitioning hardware becomes available, support
1091 		 * could be added by requiring a flag when enabling
1092 		 * KVM_CAP_MIPS_MSA capability to indicate that userland knows
1093 		 * to save/restore the appropriate extra state.
1094 		 */
1095 		r = cpu_has_msa && !(boot_cpu_data.msa_id & MSA_IR_WRPF);
1096 		break;
1097 	default:
1098 		r = kvm_mips_callbacks->check_extension(kvm, ext);
1099 		break;
1100 	}
1101 	return r;
1102 }
1103 
1104 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
1105 {
1106 	return kvm_mips_pending_timer(vcpu) ||
1107 		kvm_read_c0_guest_cause(vcpu->arch.cop0) & C_TI;
1108 }
1109 
1110 int kvm_arch_vcpu_dump_regs(struct kvm_vcpu *vcpu)
1111 {
1112 	int i;
1113 	struct mips_coproc *cop0;
1114 
1115 	if (!vcpu)
1116 		return -1;
1117 
1118 	kvm_debug("VCPU Register Dump:\n");
1119 	kvm_debug("\tpc = 0x%08lx\n", vcpu->arch.pc);
1120 	kvm_debug("\texceptions: %08lx\n", vcpu->arch.pending_exceptions);
1121 
1122 	for (i = 0; i < 32; i += 4) {
1123 		kvm_debug("\tgpr%02d: %08lx %08lx %08lx %08lx\n", i,
1124 		       vcpu->arch.gprs[i],
1125 		       vcpu->arch.gprs[i + 1],
1126 		       vcpu->arch.gprs[i + 2], vcpu->arch.gprs[i + 3]);
1127 	}
1128 	kvm_debug("\thi: 0x%08lx\n", vcpu->arch.hi);
1129 	kvm_debug("\tlo: 0x%08lx\n", vcpu->arch.lo);
1130 
1131 	cop0 = vcpu->arch.cop0;
1132 	kvm_debug("\tStatus: 0x%08x, Cause: 0x%08x\n",
1133 		  kvm_read_c0_guest_status(cop0),
1134 		  kvm_read_c0_guest_cause(cop0));
1135 
1136 	kvm_debug("\tEPC: 0x%08lx\n", kvm_read_c0_guest_epc(cop0));
1137 
1138 	return 0;
1139 }
1140 
1141 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1142 {
1143 	int i;
1144 
1145 	vcpu_load(vcpu);
1146 
1147 	for (i = 1; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1148 		vcpu->arch.gprs[i] = regs->gpr[i];
1149 	vcpu->arch.gprs[0] = 0; /* zero is special, and cannot be set. */
1150 	vcpu->arch.hi = regs->hi;
1151 	vcpu->arch.lo = regs->lo;
1152 	vcpu->arch.pc = regs->pc;
1153 
1154 	vcpu_put(vcpu);
1155 	return 0;
1156 }
1157 
1158 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1159 {
1160 	int i;
1161 
1162 	vcpu_load(vcpu);
1163 
1164 	for (i = 0; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1165 		regs->gpr[i] = vcpu->arch.gprs[i];
1166 
1167 	regs->hi = vcpu->arch.hi;
1168 	regs->lo = vcpu->arch.lo;
1169 	regs->pc = vcpu->arch.pc;
1170 
1171 	vcpu_put(vcpu);
1172 	return 0;
1173 }
1174 
1175 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
1176 				  struct kvm_translation *tr)
1177 {
1178 	return 0;
1179 }
1180 
1181 static void kvm_mips_set_c0_status(void)
1182 {
1183 	u32 status = read_c0_status();
1184 
1185 	if (cpu_has_dsp)
1186 		status |= (ST0_MX);
1187 
1188 	write_c0_status(status);
1189 	ehb();
1190 }
1191 
1192 /*
1193  * Return value is in the form (errcode<<2 | RESUME_FLAG_HOST | RESUME_FLAG_NV)
1194  */
1195 int kvm_mips_handle_exit(struct kvm_vcpu *vcpu)
1196 {
1197 	struct kvm_run *run = vcpu->run;
1198 	u32 cause = vcpu->arch.host_cp0_cause;
1199 	u32 exccode = (cause >> CAUSEB_EXCCODE) & 0x1f;
1200 	u32 __user *opc = (u32 __user *) vcpu->arch.pc;
1201 	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
1202 	enum emulation_result er = EMULATE_DONE;
1203 	u32 inst;
1204 	int ret = RESUME_GUEST;
1205 
1206 	vcpu->mode = OUTSIDE_GUEST_MODE;
1207 
1208 	/* Set a default exit reason */
1209 	run->exit_reason = KVM_EXIT_UNKNOWN;
1210 	run->ready_for_interrupt_injection = 1;
1211 
1212 	/*
1213 	 * Set the appropriate status bits based on host CPU features,
1214 	 * before we hit the scheduler
1215 	 */
1216 	kvm_mips_set_c0_status();
1217 
1218 	local_irq_enable();
1219 
1220 	kvm_debug("kvm_mips_handle_exit: cause: %#x, PC: %p, kvm_run: %p, kvm_vcpu: %p\n",
1221 			cause, opc, run, vcpu);
1222 	trace_kvm_exit(vcpu, exccode);
1223 
1224 	switch (exccode) {
1225 	case EXCCODE_INT:
1226 		kvm_debug("[%d]EXCCODE_INT @ %p\n", vcpu->vcpu_id, opc);
1227 
1228 		++vcpu->stat.int_exits;
1229 
1230 		if (need_resched())
1231 			cond_resched();
1232 
1233 		ret = RESUME_GUEST;
1234 		break;
1235 
1236 	case EXCCODE_CPU:
1237 		kvm_debug("EXCCODE_CPU: @ PC: %p\n", opc);
1238 
1239 		++vcpu->stat.cop_unusable_exits;
1240 		ret = kvm_mips_callbacks->handle_cop_unusable(vcpu);
1241 		/* XXXKYMA: Might need to return to user space */
1242 		if (run->exit_reason == KVM_EXIT_IRQ_WINDOW_OPEN)
1243 			ret = RESUME_HOST;
1244 		break;
1245 
1246 	case EXCCODE_MOD:
1247 		++vcpu->stat.tlbmod_exits;
1248 		ret = kvm_mips_callbacks->handle_tlb_mod(vcpu);
1249 		break;
1250 
1251 	case EXCCODE_TLBS:
1252 		kvm_debug("TLB ST fault:  cause %#x, status %#x, PC: %p, BadVaddr: %#lx\n",
1253 			  cause, kvm_read_c0_guest_status(vcpu->arch.cop0), opc,
1254 			  badvaddr);
1255 
1256 		++vcpu->stat.tlbmiss_st_exits;
1257 		ret = kvm_mips_callbacks->handle_tlb_st_miss(vcpu);
1258 		break;
1259 
1260 	case EXCCODE_TLBL:
1261 		kvm_debug("TLB LD fault: cause %#x, PC: %p, BadVaddr: %#lx\n",
1262 			  cause, opc, badvaddr);
1263 
1264 		++vcpu->stat.tlbmiss_ld_exits;
1265 		ret = kvm_mips_callbacks->handle_tlb_ld_miss(vcpu);
1266 		break;
1267 
1268 	case EXCCODE_ADES:
1269 		++vcpu->stat.addrerr_st_exits;
1270 		ret = kvm_mips_callbacks->handle_addr_err_st(vcpu);
1271 		break;
1272 
1273 	case EXCCODE_ADEL:
1274 		++vcpu->stat.addrerr_ld_exits;
1275 		ret = kvm_mips_callbacks->handle_addr_err_ld(vcpu);
1276 		break;
1277 
1278 	case EXCCODE_SYS:
1279 		++vcpu->stat.syscall_exits;
1280 		ret = kvm_mips_callbacks->handle_syscall(vcpu);
1281 		break;
1282 
1283 	case EXCCODE_RI:
1284 		++vcpu->stat.resvd_inst_exits;
1285 		ret = kvm_mips_callbacks->handle_res_inst(vcpu);
1286 		break;
1287 
1288 	case EXCCODE_BP:
1289 		++vcpu->stat.break_inst_exits;
1290 		ret = kvm_mips_callbacks->handle_break(vcpu);
1291 		break;
1292 
1293 	case EXCCODE_TR:
1294 		++vcpu->stat.trap_inst_exits;
1295 		ret = kvm_mips_callbacks->handle_trap(vcpu);
1296 		break;
1297 
1298 	case EXCCODE_MSAFPE:
1299 		++vcpu->stat.msa_fpe_exits;
1300 		ret = kvm_mips_callbacks->handle_msa_fpe(vcpu);
1301 		break;
1302 
1303 	case EXCCODE_FPE:
1304 		++vcpu->stat.fpe_exits;
1305 		ret = kvm_mips_callbacks->handle_fpe(vcpu);
1306 		break;
1307 
1308 	case EXCCODE_MSADIS:
1309 		++vcpu->stat.msa_disabled_exits;
1310 		ret = kvm_mips_callbacks->handle_msa_disabled(vcpu);
1311 		break;
1312 
1313 	case EXCCODE_GE:
1314 		/* defer exit accounting to handler */
1315 		ret = kvm_mips_callbacks->handle_guest_exit(vcpu);
1316 		break;
1317 
1318 	default:
1319 		if (cause & CAUSEF_BD)
1320 			opc += 1;
1321 		inst = 0;
1322 		kvm_get_badinstr(opc, vcpu, &inst);
1323 		kvm_err("Exception Code: %d, not yet handled, @ PC: %p, inst: 0x%08x  BadVaddr: %#lx Status: %#x\n",
1324 			exccode, opc, inst, badvaddr,
1325 			kvm_read_c0_guest_status(vcpu->arch.cop0));
1326 		kvm_arch_vcpu_dump_regs(vcpu);
1327 		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1328 		ret = RESUME_HOST;
1329 		break;
1330 
1331 	}
1332 
1333 	local_irq_disable();
1334 
1335 	if (ret == RESUME_GUEST)
1336 		kvm_vz_acquire_htimer(vcpu);
1337 
1338 	if (er == EMULATE_DONE && !(ret & RESUME_HOST))
1339 		kvm_mips_deliver_interrupts(vcpu, cause);
1340 
1341 	if (!(ret & RESUME_HOST)) {
1342 		/* Only check for signals if not already exiting to userspace */
1343 		if (signal_pending(current)) {
1344 			run->exit_reason = KVM_EXIT_INTR;
1345 			ret = (-EINTR << 2) | RESUME_HOST;
1346 			++vcpu->stat.signal_exits;
1347 			trace_kvm_exit(vcpu, KVM_TRACE_EXIT_SIGNAL);
1348 		}
1349 	}
1350 
1351 	if (ret == RESUME_GUEST) {
1352 		trace_kvm_reenter(vcpu);
1353 
1354 		/*
1355 		 * Make sure the read of VCPU requests in vcpu_reenter()
1356 		 * callback is not reordered ahead of the write to vcpu->mode,
1357 		 * or we could miss a TLB flush request while the requester sees
1358 		 * the VCPU as outside of guest mode and not needing an IPI.
1359 		 */
1360 		smp_store_mb(vcpu->mode, IN_GUEST_MODE);
1361 
1362 		kvm_mips_callbacks->vcpu_reenter(vcpu);
1363 
1364 		/*
1365 		 * If FPU / MSA are enabled (i.e. the guest's FPU / MSA context
1366 		 * is live), restore FCR31 / MSACSR.
1367 		 *
1368 		 * This should be before returning to the guest exception
1369 		 * vector, as it may well cause an [MSA] FP exception if there
1370 		 * are pending exception bits unmasked. (see
1371 		 * kvm_mips_csr_die_notifier() for how that is handled).
1372 		 */
1373 		if (kvm_mips_guest_has_fpu(&vcpu->arch) &&
1374 		    read_c0_status() & ST0_CU1)
1375 			__kvm_restore_fcsr(&vcpu->arch);
1376 
1377 		if (kvm_mips_guest_has_msa(&vcpu->arch) &&
1378 		    read_c0_config5() & MIPS_CONF5_MSAEN)
1379 			__kvm_restore_msacsr(&vcpu->arch);
1380 	}
1381 	return ret;
1382 }
1383 
1384 /* Enable FPU for guest and restore context */
1385 void kvm_own_fpu(struct kvm_vcpu *vcpu)
1386 {
1387 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1388 	unsigned int sr, cfg5;
1389 
1390 	preempt_disable();
1391 
1392 	sr = kvm_read_c0_guest_status(cop0);
1393 
1394 	/*
1395 	 * If MSA state is already live, it is undefined how it interacts with
1396 	 * FR=0 FPU state, and we don't want to hit reserved instruction
1397 	 * exceptions trying to save the MSA state later when CU=1 && FR=1, so
1398 	 * play it safe and save it first.
1399 	 */
1400 	if (cpu_has_msa && sr & ST0_CU1 && !(sr & ST0_FR) &&
1401 	    vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA)
1402 		kvm_lose_fpu(vcpu);
1403 
1404 	/*
1405 	 * Enable FPU for guest
1406 	 * We set FR and FRE according to guest context
1407 	 */
1408 	change_c0_status(ST0_CU1 | ST0_FR, sr);
1409 	if (cpu_has_fre) {
1410 		cfg5 = kvm_read_c0_guest_config5(cop0);
1411 		change_c0_config5(MIPS_CONF5_FRE, cfg5);
1412 	}
1413 	enable_fpu_hazard();
1414 
1415 	/* If guest FPU state not active, restore it now */
1416 	if (!(vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU)) {
1417 		__kvm_restore_fpu(&vcpu->arch);
1418 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1419 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_FPU);
1420 	} else {
1421 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_FPU);
1422 	}
1423 
1424 	preempt_enable();
1425 }
1426 
1427 #ifdef CONFIG_CPU_HAS_MSA
1428 /* Enable MSA for guest and restore context */
1429 void kvm_own_msa(struct kvm_vcpu *vcpu)
1430 {
1431 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1432 	unsigned int sr, cfg5;
1433 
1434 	preempt_disable();
1435 
1436 	/*
1437 	 * Enable FPU if enabled in guest, since we're restoring FPU context
1438 	 * anyway. We set FR and FRE according to guest context.
1439 	 */
1440 	if (kvm_mips_guest_has_fpu(&vcpu->arch)) {
1441 		sr = kvm_read_c0_guest_status(cop0);
1442 
1443 		/*
1444 		 * If FR=0 FPU state is already live, it is undefined how it
1445 		 * interacts with MSA state, so play it safe and save it first.
1446 		 */
1447 		if (!(sr & ST0_FR) &&
1448 		    (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU |
1449 				KVM_MIPS_AUX_MSA)) == KVM_MIPS_AUX_FPU)
1450 			kvm_lose_fpu(vcpu);
1451 
1452 		change_c0_status(ST0_CU1 | ST0_FR, sr);
1453 		if (sr & ST0_CU1 && cpu_has_fre) {
1454 			cfg5 = kvm_read_c0_guest_config5(cop0);
1455 			change_c0_config5(MIPS_CONF5_FRE, cfg5);
1456 		}
1457 	}
1458 
1459 	/* Enable MSA for guest */
1460 	set_c0_config5(MIPS_CONF5_MSAEN);
1461 	enable_fpu_hazard();
1462 
1463 	switch (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA)) {
1464 	case KVM_MIPS_AUX_FPU:
1465 		/*
1466 		 * Guest FPU state already loaded, only restore upper MSA state
1467 		 */
1468 		__kvm_restore_msa_upper(&vcpu->arch);
1469 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1470 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_MSA);
1471 		break;
1472 	case 0:
1473 		/* Neither FPU or MSA already active, restore full MSA state */
1474 		__kvm_restore_msa(&vcpu->arch);
1475 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1476 		if (kvm_mips_guest_has_fpu(&vcpu->arch))
1477 			vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1478 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE,
1479 			      KVM_TRACE_AUX_FPU_MSA);
1480 		break;
1481 	default:
1482 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_MSA);
1483 		break;
1484 	}
1485 
1486 	preempt_enable();
1487 }
1488 #endif
1489 
1490 /* Drop FPU & MSA without saving it */
1491 void kvm_drop_fpu(struct kvm_vcpu *vcpu)
1492 {
1493 	preempt_disable();
1494 	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1495 		disable_msa();
1496 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_MSA);
1497 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_MSA;
1498 	}
1499 	if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1500 		clear_c0_status(ST0_CU1 | ST0_FR);
1501 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_FPU);
1502 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1503 	}
1504 	preempt_enable();
1505 }
1506 
1507 /* Save and disable FPU & MSA */
1508 void kvm_lose_fpu(struct kvm_vcpu *vcpu)
1509 {
1510 	/*
1511 	 * With T&E, FPU & MSA get disabled in root context (hardware) when it
1512 	 * is disabled in guest context (software), but the register state in
1513 	 * the hardware may still be in use.
1514 	 * This is why we explicitly re-enable the hardware before saving.
1515 	 */
1516 
1517 	preempt_disable();
1518 	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1519 		__kvm_save_msa(&vcpu->arch);
1520 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU_MSA);
1521 
1522 		/* Disable MSA & FPU */
1523 		disable_msa();
1524 		if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1525 			clear_c0_status(ST0_CU1 | ST0_FR);
1526 			disable_fpu_hazard();
1527 		}
1528 		vcpu->arch.aux_inuse &= ~(KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA);
1529 	} else if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1530 		__kvm_save_fpu(&vcpu->arch);
1531 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1532 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU);
1533 
1534 		/* Disable FPU */
1535 		clear_c0_status(ST0_CU1 | ST0_FR);
1536 		disable_fpu_hazard();
1537 	}
1538 	preempt_enable();
1539 }
1540 
1541 /*
1542  * Step over a specific ctc1 to FCSR and a specific ctcmsa to MSACSR which are
1543  * used to restore guest FCSR/MSACSR state and may trigger a "harmless" FP/MSAFP
1544  * exception if cause bits are set in the value being written.
1545  */
1546 static int kvm_mips_csr_die_notify(struct notifier_block *self,
1547 				   unsigned long cmd, void *ptr)
1548 {
1549 	struct die_args *args = (struct die_args *)ptr;
1550 	struct pt_regs *regs = args->regs;
1551 	unsigned long pc;
1552 
1553 	/* Only interested in FPE and MSAFPE */
1554 	if (cmd != DIE_FP && cmd != DIE_MSAFP)
1555 		return NOTIFY_DONE;
1556 
1557 	/* Return immediately if guest context isn't active */
1558 	if (!(current->flags & PF_VCPU))
1559 		return NOTIFY_DONE;
1560 
1561 	/* Should never get here from user mode */
1562 	BUG_ON(user_mode(regs));
1563 
1564 	pc = instruction_pointer(regs);
1565 	switch (cmd) {
1566 	case DIE_FP:
1567 		/* match 2nd instruction in __kvm_restore_fcsr */
1568 		if (pc != (unsigned long)&__kvm_restore_fcsr + 4)
1569 			return NOTIFY_DONE;
1570 		break;
1571 	case DIE_MSAFP:
1572 		/* match 2nd/3rd instruction in __kvm_restore_msacsr */
1573 		if (!cpu_has_msa ||
1574 		    pc < (unsigned long)&__kvm_restore_msacsr + 4 ||
1575 		    pc > (unsigned long)&__kvm_restore_msacsr + 8)
1576 			return NOTIFY_DONE;
1577 		break;
1578 	}
1579 
1580 	/* Move PC forward a little and continue executing */
1581 	instruction_pointer(regs) += 4;
1582 
1583 	return NOTIFY_STOP;
1584 }
1585 
1586 static struct notifier_block kvm_mips_csr_die_notifier = {
1587 	.notifier_call = kvm_mips_csr_die_notify,
1588 };
1589 
1590 static u32 kvm_default_priority_to_irq[MIPS_EXC_MAX] = {
1591 	[MIPS_EXC_INT_TIMER] = C_IRQ5,
1592 	[MIPS_EXC_INT_IO_1]  = C_IRQ0,
1593 	[MIPS_EXC_INT_IPI_1] = C_IRQ1,
1594 	[MIPS_EXC_INT_IPI_2] = C_IRQ2,
1595 };
1596 
1597 static u32 kvm_loongson3_priority_to_irq[MIPS_EXC_MAX] = {
1598 	[MIPS_EXC_INT_TIMER] = C_IRQ5,
1599 	[MIPS_EXC_INT_IO_1]  = C_IRQ0,
1600 	[MIPS_EXC_INT_IO_2]  = C_IRQ1,
1601 	[MIPS_EXC_INT_IPI_1] = C_IRQ4,
1602 };
1603 
1604 u32 *kvm_priority_to_irq = kvm_default_priority_to_irq;
1605 
1606 u32 kvm_irq_to_priority(u32 irq)
1607 {
1608 	int i;
1609 
1610 	for (i = MIPS_EXC_INT_TIMER; i < MIPS_EXC_MAX; i++) {
1611 		if (kvm_priority_to_irq[i] == (1 << (irq + 8)))
1612 			return i;
1613 	}
1614 
1615 	return MIPS_EXC_MAX;
1616 }
1617 
1618 static int __init kvm_mips_init(void)
1619 {
1620 	int ret;
1621 
1622 	if (cpu_has_mmid) {
1623 		pr_warn("KVM does not yet support MMIDs. KVM Disabled\n");
1624 		return -EOPNOTSUPP;
1625 	}
1626 
1627 	ret = kvm_mips_entry_setup();
1628 	if (ret)
1629 		return ret;
1630 
1631 	ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
1632 
1633 	if (ret)
1634 		return ret;
1635 
1636 	if (boot_cpu_type() == CPU_LOONGSON64)
1637 		kvm_priority_to_irq = kvm_loongson3_priority_to_irq;
1638 
1639 	register_die_notifier(&kvm_mips_csr_die_notifier);
1640 
1641 	return 0;
1642 }
1643 
1644 static void __exit kvm_mips_exit(void)
1645 {
1646 	kvm_exit();
1647 
1648 	unregister_die_notifier(&kvm_mips_csr_die_notifier);
1649 }
1650 
1651 module_init(kvm_mips_init);
1652 module_exit(kvm_mips_exit);
1653 
1654 EXPORT_TRACEPOINT_SYMBOL(kvm_exit);
1655