xref: /openbmc/linux/arch/mips/kvm/mips.c (revision 2f61c664)
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 struct kvm_stats_debugfs_item debugfs_entries[] = {
42 	VCPU_STAT("wait", wait_exits),
43 	VCPU_STAT("cache", cache_exits),
44 	VCPU_STAT("signal", signal_exits),
45 	VCPU_STAT("interrupt", int_exits),
46 	VCPU_STAT("cop_unusable", cop_unusable_exits),
47 	VCPU_STAT("tlbmod", tlbmod_exits),
48 	VCPU_STAT("tlbmiss_ld", tlbmiss_ld_exits),
49 	VCPU_STAT("tlbmiss_st", tlbmiss_st_exits),
50 	VCPU_STAT("addrerr_st", addrerr_st_exits),
51 	VCPU_STAT("addrerr_ld", addrerr_ld_exits),
52 	VCPU_STAT("syscall", syscall_exits),
53 	VCPU_STAT("resvd_inst", resvd_inst_exits),
54 	VCPU_STAT("break_inst", break_inst_exits),
55 	VCPU_STAT("trap_inst", trap_inst_exits),
56 	VCPU_STAT("msa_fpe", msa_fpe_exits),
57 	VCPU_STAT("fpe", fpe_exits),
58 	VCPU_STAT("msa_disabled", msa_disabled_exits),
59 	VCPU_STAT("flush_dcache", flush_dcache_exits),
60 	VCPU_STAT("vz_gpsi", vz_gpsi_exits),
61 	VCPU_STAT("vz_gsfc", vz_gsfc_exits),
62 	VCPU_STAT("vz_hc", vz_hc_exits),
63 	VCPU_STAT("vz_grr", vz_grr_exits),
64 	VCPU_STAT("vz_gva", vz_gva_exits),
65 	VCPU_STAT("vz_ghfc", vz_ghfc_exits),
66 	VCPU_STAT("vz_gpa", vz_gpa_exits),
67 	VCPU_STAT("vz_resvd", vz_resvd_exits),
68 #ifdef CONFIG_CPU_LOONGSON64
69 	VCPU_STAT("vz_cpucfg", vz_cpucfg_exits),
70 #endif
71 	VCPU_STAT("halt_successful_poll", halt_successful_poll),
72 	VCPU_STAT("halt_attempted_poll", halt_attempted_poll),
73 	VCPU_STAT("halt_poll_invalid", halt_poll_invalid),
74 	VCPU_STAT("halt_wakeup", halt_wakeup),
75 	VCPU_STAT("halt_poll_success_ns", halt_poll_success_ns),
76 	VCPU_STAT("halt_poll_fail_ns", halt_poll_fail_ns),
77 	{NULL}
78 };
79 
80 bool kvm_trace_guest_mode_change;
81 
82 int kvm_guest_mode_change_trace_reg(void)
83 {
84 	kvm_trace_guest_mode_change = true;
85 	return 0;
86 }
87 
88 void kvm_guest_mode_change_trace_unreg(void)
89 {
90 	kvm_trace_guest_mode_change = false;
91 }
92 
93 /*
94  * XXXKYMA: We are simulatoring a processor that has the WII bit set in
95  * Config7, so we are "runnable" if interrupts are pending
96  */
97 int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
98 {
99 	return !!(vcpu->arch.pending_exceptions);
100 }
101 
102 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
103 {
104 	return false;
105 }
106 
107 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
108 {
109 	return 1;
110 }
111 
112 int kvm_arch_hardware_enable(void)
113 {
114 	return kvm_mips_callbacks->hardware_enable();
115 }
116 
117 void kvm_arch_hardware_disable(void)
118 {
119 	kvm_mips_callbacks->hardware_disable();
120 }
121 
122 int kvm_arch_hardware_setup(void *opaque)
123 {
124 	return 0;
125 }
126 
127 int kvm_arch_check_processor_compat(void *opaque)
128 {
129 	return 0;
130 }
131 
132 extern void kvm_init_loongson_ipi(struct kvm *kvm);
133 
134 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
135 {
136 	switch (type) {
137 	case KVM_VM_MIPS_AUTO:
138 		break;
139 	case KVM_VM_MIPS_VZ:
140 		break;
141 	default:
142 		/* Unsupported KVM type */
143 		return -EINVAL;
144 	}
145 
146 	/* Allocate page table to map GPA -> RPA */
147 	kvm->arch.gpa_mm.pgd = kvm_pgd_alloc();
148 	if (!kvm->arch.gpa_mm.pgd)
149 		return -ENOMEM;
150 
151 #ifdef CONFIG_CPU_LOONGSON64
152 	kvm_init_loongson_ipi(kvm);
153 #endif
154 
155 	return 0;
156 }
157 
158 void kvm_mips_free_vcpus(struct kvm *kvm)
159 {
160 	unsigned int i;
161 	struct kvm_vcpu *vcpu;
162 
163 	kvm_for_each_vcpu(i, vcpu, kvm) {
164 		kvm_vcpu_destroy(vcpu);
165 	}
166 
167 	mutex_lock(&kvm->lock);
168 
169 	for (i = 0; i < atomic_read(&kvm->online_vcpus); i++)
170 		kvm->vcpus[i] = NULL;
171 
172 	atomic_set(&kvm->online_vcpus, 0);
173 
174 	mutex_unlock(&kvm->lock);
175 }
176 
177 static void kvm_mips_free_gpa_pt(struct kvm *kvm)
178 {
179 	/* It should always be safe to remove after flushing the whole range */
180 	WARN_ON(!kvm_mips_flush_gpa_pt(kvm, 0, ~0));
181 	pgd_free(NULL, kvm->arch.gpa_mm.pgd);
182 }
183 
184 void kvm_arch_destroy_vm(struct kvm *kvm)
185 {
186 	kvm_mips_free_vcpus(kvm);
187 	kvm_mips_free_gpa_pt(kvm);
188 }
189 
190 long kvm_arch_dev_ioctl(struct file *filp, unsigned int ioctl,
191 			unsigned long arg)
192 {
193 	return -ENOIOCTLCMD;
194 }
195 
196 void kvm_arch_flush_shadow_all(struct kvm *kvm)
197 {
198 	/* Flush whole GPA */
199 	kvm_mips_flush_gpa_pt(kvm, 0, ~0);
200 	kvm_flush_remote_tlbs(kvm);
201 }
202 
203 void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
204 				   struct kvm_memory_slot *slot)
205 {
206 	/*
207 	 * The slot has been made invalid (ready for moving or deletion), so we
208 	 * need to ensure that it can no longer be accessed by any guest VCPUs.
209 	 */
210 
211 	spin_lock(&kvm->mmu_lock);
212 	/* Flush slot from GPA */
213 	kvm_mips_flush_gpa_pt(kvm, slot->base_gfn,
214 			      slot->base_gfn + slot->npages - 1);
215 	kvm_arch_flush_remote_tlbs_memslot(kvm, slot);
216 	spin_unlock(&kvm->mmu_lock);
217 }
218 
219 int kvm_arch_prepare_memory_region(struct kvm *kvm,
220 				   struct kvm_memory_slot *memslot,
221 				   const struct kvm_userspace_memory_region *mem,
222 				   enum kvm_mr_change change)
223 {
224 	return 0;
225 }
226 
227 void kvm_arch_commit_memory_region(struct kvm *kvm,
228 				   const struct kvm_userspace_memory_region *mem,
229 				   struct kvm_memory_slot *old,
230 				   const struct kvm_memory_slot *new,
231 				   enum kvm_mr_change change)
232 {
233 	int needs_flush;
234 
235 	kvm_debug("%s: kvm: %p slot: %d, GPA: %llx, size: %llx, QVA: %llx\n",
236 		  __func__, kvm, mem->slot, mem->guest_phys_addr,
237 		  mem->memory_size, mem->userspace_addr);
238 
239 	/*
240 	 * If dirty page logging is enabled, write protect all pages in the slot
241 	 * ready for dirty logging.
242 	 *
243 	 * There is no need to do this in any of the following cases:
244 	 * CREATE:	No dirty mappings will already exist.
245 	 * MOVE/DELETE:	The old mappings will already have been cleaned up by
246 	 *		kvm_arch_flush_shadow_memslot()
247 	 */
248 	if (change == KVM_MR_FLAGS_ONLY &&
249 	    (!(old->flags & KVM_MEM_LOG_DIRTY_PAGES) &&
250 	     new->flags & KVM_MEM_LOG_DIRTY_PAGES)) {
251 		spin_lock(&kvm->mmu_lock);
252 		/* Write protect GPA page table entries */
253 		needs_flush = kvm_mips_mkclean_gpa_pt(kvm, new->base_gfn,
254 					new->base_gfn + new->npages - 1);
255 		if (needs_flush)
256 			kvm_arch_flush_remote_tlbs_memslot(kvm, new);
257 		spin_unlock(&kvm->mmu_lock);
258 	}
259 }
260 
261 static inline void dump_handler(const char *symbol, void *start, void *end)
262 {
263 	u32 *p;
264 
265 	pr_debug("LEAF(%s)\n", symbol);
266 
267 	pr_debug("\t.set push\n");
268 	pr_debug("\t.set noreorder\n");
269 
270 	for (p = start; p < (u32 *)end; ++p)
271 		pr_debug("\t.word\t0x%08x\t\t# %p\n", *p, p);
272 
273 	pr_debug("\t.set\tpop\n");
274 
275 	pr_debug("\tEND(%s)\n", symbol);
276 }
277 
278 /* low level hrtimer wake routine */
279 static enum hrtimer_restart kvm_mips_comparecount_wakeup(struct hrtimer *timer)
280 {
281 	struct kvm_vcpu *vcpu;
282 
283 	vcpu = container_of(timer, struct kvm_vcpu, arch.comparecount_timer);
284 
285 	kvm_mips_callbacks->queue_timer_int(vcpu);
286 
287 	vcpu->arch.wait = 0;
288 	rcuwait_wake_up(&vcpu->wait);
289 
290 	return kvm_mips_count_timeout(vcpu);
291 }
292 
293 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
294 {
295 	return 0;
296 }
297 
298 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
299 {
300 	int err, size;
301 	void *gebase, *p, *handler, *refill_start, *refill_end;
302 	int i;
303 
304 	kvm_debug("kvm @ %p: create cpu %d at %p\n",
305 		  vcpu->kvm, vcpu->vcpu_id, vcpu);
306 
307 	err = kvm_mips_callbacks->vcpu_init(vcpu);
308 	if (err)
309 		return err;
310 
311 	hrtimer_init(&vcpu->arch.comparecount_timer, CLOCK_MONOTONIC,
312 		     HRTIMER_MODE_REL);
313 	vcpu->arch.comparecount_timer.function = kvm_mips_comparecount_wakeup;
314 
315 	/*
316 	 * Allocate space for host mode exception handlers that handle
317 	 * guest mode exits
318 	 */
319 	if (cpu_has_veic || cpu_has_vint)
320 		size = 0x200 + VECTORSPACING * 64;
321 	else
322 		size = 0x4000;
323 
324 	gebase = kzalloc(ALIGN(size, PAGE_SIZE), GFP_KERNEL);
325 
326 	if (!gebase) {
327 		err = -ENOMEM;
328 		goto out_uninit_vcpu;
329 	}
330 	kvm_debug("Allocated %d bytes for KVM Exception Handlers @ %p\n",
331 		  ALIGN(size, PAGE_SIZE), gebase);
332 
333 	/*
334 	 * Check new ebase actually fits in CP0_EBase. The lack of a write gate
335 	 * limits us to the low 512MB of physical address space. If the memory
336 	 * we allocate is out of range, just give up now.
337 	 */
338 	if (!cpu_has_ebase_wg && virt_to_phys(gebase) >= 0x20000000) {
339 		kvm_err("CP0_EBase.WG required for guest exception base %pK\n",
340 			gebase);
341 		err = -ENOMEM;
342 		goto out_free_gebase;
343 	}
344 
345 	/* Save new ebase */
346 	vcpu->arch.guest_ebase = gebase;
347 
348 	/* Build guest exception vectors dynamically in unmapped memory */
349 	handler = gebase + 0x2000;
350 
351 	/* TLB refill (or XTLB refill on 64-bit VZ where KX=1) */
352 	refill_start = gebase;
353 	if (IS_ENABLED(CONFIG_64BIT))
354 		refill_start += 0x080;
355 	refill_end = kvm_mips_build_tlb_refill_exception(refill_start, handler);
356 
357 	/* General Exception Entry point */
358 	kvm_mips_build_exception(gebase + 0x180, handler);
359 
360 	/* For vectored interrupts poke the exception code @ all offsets 0-7 */
361 	for (i = 0; i < 8; i++) {
362 		kvm_debug("L1 Vectored handler @ %p\n",
363 			  gebase + 0x200 + (i * VECTORSPACING));
364 		kvm_mips_build_exception(gebase + 0x200 + i * VECTORSPACING,
365 					 handler);
366 	}
367 
368 	/* General exit handler */
369 	p = handler;
370 	p = kvm_mips_build_exit(p);
371 
372 	/* Guest entry routine */
373 	vcpu->arch.vcpu_run = p;
374 	p = kvm_mips_build_vcpu_run(p);
375 
376 	/* Dump the generated code */
377 	pr_debug("#include <asm/asm.h>\n");
378 	pr_debug("#include <asm/regdef.h>\n");
379 	pr_debug("\n");
380 	dump_handler("kvm_vcpu_run", vcpu->arch.vcpu_run, p);
381 	dump_handler("kvm_tlb_refill", refill_start, refill_end);
382 	dump_handler("kvm_gen_exc", gebase + 0x180, gebase + 0x200);
383 	dump_handler("kvm_exit", gebase + 0x2000, vcpu->arch.vcpu_run);
384 
385 	/* Invalidate the icache for these ranges */
386 	flush_icache_range((unsigned long)gebase,
387 			   (unsigned long)gebase + ALIGN(size, PAGE_SIZE));
388 
389 	/* Init */
390 	vcpu->arch.last_sched_cpu = -1;
391 	vcpu->arch.last_exec_cpu = -1;
392 
393 	/* Initial guest state */
394 	err = kvm_mips_callbacks->vcpu_setup(vcpu);
395 	if (err)
396 		goto out_free_gebase;
397 
398 	return 0;
399 
400 out_free_gebase:
401 	kfree(gebase);
402 out_uninit_vcpu:
403 	kvm_mips_callbacks->vcpu_uninit(vcpu);
404 	return err;
405 }
406 
407 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
408 {
409 	hrtimer_cancel(&vcpu->arch.comparecount_timer);
410 
411 	kvm_mips_dump_stats(vcpu);
412 
413 	kvm_mmu_free_memory_caches(vcpu);
414 	kfree(vcpu->arch.guest_ebase);
415 
416 	kvm_mips_callbacks->vcpu_uninit(vcpu);
417 }
418 
419 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
420 					struct kvm_guest_debug *dbg)
421 {
422 	return -ENOIOCTLCMD;
423 }
424 
425 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
426 {
427 	int r = -EINTR;
428 
429 	vcpu_load(vcpu);
430 
431 	kvm_sigset_activate(vcpu);
432 
433 	if (vcpu->mmio_needed) {
434 		if (!vcpu->mmio_is_write)
435 			kvm_mips_complete_mmio_load(vcpu);
436 		vcpu->mmio_needed = 0;
437 	}
438 
439 	if (vcpu->run->immediate_exit)
440 		goto out;
441 
442 	lose_fpu(1);
443 
444 	local_irq_disable();
445 	guest_enter_irqoff();
446 	trace_kvm_enter(vcpu);
447 
448 	/*
449 	 * Make sure the read of VCPU requests in vcpu_run() callback is not
450 	 * reordered ahead of the write to vcpu->mode, or we could miss a TLB
451 	 * flush request while the requester sees the VCPU as outside of guest
452 	 * mode and not needing an IPI.
453 	 */
454 	smp_store_mb(vcpu->mode, IN_GUEST_MODE);
455 
456 	r = kvm_mips_callbacks->vcpu_run(vcpu);
457 
458 	trace_kvm_out(vcpu);
459 	guest_exit_irqoff();
460 	local_irq_enable();
461 
462 out:
463 	kvm_sigset_deactivate(vcpu);
464 
465 	vcpu_put(vcpu);
466 	return r;
467 }
468 
469 int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
470 			     struct kvm_mips_interrupt *irq)
471 {
472 	int intr = (int)irq->irq;
473 	struct kvm_vcpu *dvcpu = NULL;
474 
475 	if (intr == kvm_priority_to_irq[MIPS_EXC_INT_IPI_1] ||
476 	    intr == kvm_priority_to_irq[MIPS_EXC_INT_IPI_2] ||
477 	    intr == (-kvm_priority_to_irq[MIPS_EXC_INT_IPI_1]) ||
478 	    intr == (-kvm_priority_to_irq[MIPS_EXC_INT_IPI_2]))
479 		kvm_debug("%s: CPU: %d, INTR: %d\n", __func__, irq->cpu,
480 			  (int)intr);
481 
482 	if (irq->cpu == -1)
483 		dvcpu = vcpu;
484 	else
485 		dvcpu = vcpu->kvm->vcpus[irq->cpu];
486 
487 	if (intr == 2 || intr == 3 || intr == 4 || intr == 6) {
488 		kvm_mips_callbacks->queue_io_int(dvcpu, irq);
489 
490 	} else if (intr == -2 || intr == -3 || intr == -4 || intr == -6) {
491 		kvm_mips_callbacks->dequeue_io_int(dvcpu, irq);
492 	} else {
493 		kvm_err("%s: invalid interrupt ioctl (%d:%d)\n", __func__,
494 			irq->cpu, irq->irq);
495 		return -EINVAL;
496 	}
497 
498 	dvcpu->arch.wait = 0;
499 
500 	rcuwait_wake_up(&dvcpu->wait);
501 
502 	return 0;
503 }
504 
505 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
506 				    struct kvm_mp_state *mp_state)
507 {
508 	return -ENOIOCTLCMD;
509 }
510 
511 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
512 				    struct kvm_mp_state *mp_state)
513 {
514 	return -ENOIOCTLCMD;
515 }
516 
517 static u64 kvm_mips_get_one_regs[] = {
518 	KVM_REG_MIPS_R0,
519 	KVM_REG_MIPS_R1,
520 	KVM_REG_MIPS_R2,
521 	KVM_REG_MIPS_R3,
522 	KVM_REG_MIPS_R4,
523 	KVM_REG_MIPS_R5,
524 	KVM_REG_MIPS_R6,
525 	KVM_REG_MIPS_R7,
526 	KVM_REG_MIPS_R8,
527 	KVM_REG_MIPS_R9,
528 	KVM_REG_MIPS_R10,
529 	KVM_REG_MIPS_R11,
530 	KVM_REG_MIPS_R12,
531 	KVM_REG_MIPS_R13,
532 	KVM_REG_MIPS_R14,
533 	KVM_REG_MIPS_R15,
534 	KVM_REG_MIPS_R16,
535 	KVM_REG_MIPS_R17,
536 	KVM_REG_MIPS_R18,
537 	KVM_REG_MIPS_R19,
538 	KVM_REG_MIPS_R20,
539 	KVM_REG_MIPS_R21,
540 	KVM_REG_MIPS_R22,
541 	KVM_REG_MIPS_R23,
542 	KVM_REG_MIPS_R24,
543 	KVM_REG_MIPS_R25,
544 	KVM_REG_MIPS_R26,
545 	KVM_REG_MIPS_R27,
546 	KVM_REG_MIPS_R28,
547 	KVM_REG_MIPS_R29,
548 	KVM_REG_MIPS_R30,
549 	KVM_REG_MIPS_R31,
550 
551 #ifndef CONFIG_CPU_MIPSR6
552 	KVM_REG_MIPS_HI,
553 	KVM_REG_MIPS_LO,
554 #endif
555 	KVM_REG_MIPS_PC,
556 };
557 
558 static u64 kvm_mips_get_one_regs_fpu[] = {
559 	KVM_REG_MIPS_FCR_IR,
560 	KVM_REG_MIPS_FCR_CSR,
561 };
562 
563 static u64 kvm_mips_get_one_regs_msa[] = {
564 	KVM_REG_MIPS_MSA_IR,
565 	KVM_REG_MIPS_MSA_CSR,
566 };
567 
568 static unsigned long kvm_mips_num_regs(struct kvm_vcpu *vcpu)
569 {
570 	unsigned long ret;
571 
572 	ret = ARRAY_SIZE(kvm_mips_get_one_regs);
573 	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
574 		ret += ARRAY_SIZE(kvm_mips_get_one_regs_fpu) + 48;
575 		/* odd doubles */
576 		if (boot_cpu_data.fpu_id & MIPS_FPIR_F64)
577 			ret += 16;
578 	}
579 	if (kvm_mips_guest_can_have_msa(&vcpu->arch))
580 		ret += ARRAY_SIZE(kvm_mips_get_one_regs_msa) + 32;
581 	ret += kvm_mips_callbacks->num_regs(vcpu);
582 
583 	return ret;
584 }
585 
586 static int kvm_mips_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices)
587 {
588 	u64 index;
589 	unsigned int i;
590 
591 	if (copy_to_user(indices, kvm_mips_get_one_regs,
592 			 sizeof(kvm_mips_get_one_regs)))
593 		return -EFAULT;
594 	indices += ARRAY_SIZE(kvm_mips_get_one_regs);
595 
596 	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
597 		if (copy_to_user(indices, kvm_mips_get_one_regs_fpu,
598 				 sizeof(kvm_mips_get_one_regs_fpu)))
599 			return -EFAULT;
600 		indices += ARRAY_SIZE(kvm_mips_get_one_regs_fpu);
601 
602 		for (i = 0; i < 32; ++i) {
603 			index = KVM_REG_MIPS_FPR_32(i);
604 			if (copy_to_user(indices, &index, sizeof(index)))
605 				return -EFAULT;
606 			++indices;
607 
608 			/* skip odd doubles if no F64 */
609 			if (i & 1 && !(boot_cpu_data.fpu_id & MIPS_FPIR_F64))
610 				continue;
611 
612 			index = KVM_REG_MIPS_FPR_64(i);
613 			if (copy_to_user(indices, &index, sizeof(index)))
614 				return -EFAULT;
615 			++indices;
616 		}
617 	}
618 
619 	if (kvm_mips_guest_can_have_msa(&vcpu->arch)) {
620 		if (copy_to_user(indices, kvm_mips_get_one_regs_msa,
621 				 sizeof(kvm_mips_get_one_regs_msa)))
622 			return -EFAULT;
623 		indices += ARRAY_SIZE(kvm_mips_get_one_regs_msa);
624 
625 		for (i = 0; i < 32; ++i) {
626 			index = KVM_REG_MIPS_VEC_128(i);
627 			if (copy_to_user(indices, &index, sizeof(index)))
628 				return -EFAULT;
629 			++indices;
630 		}
631 	}
632 
633 	return kvm_mips_callbacks->copy_reg_indices(vcpu, indices);
634 }
635 
636 static int kvm_mips_get_reg(struct kvm_vcpu *vcpu,
637 			    const struct kvm_one_reg *reg)
638 {
639 	struct mips_coproc *cop0 = vcpu->arch.cop0;
640 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
641 	int ret;
642 	s64 v;
643 	s64 vs[2];
644 	unsigned int idx;
645 
646 	switch (reg->id) {
647 	/* General purpose registers */
648 	case KVM_REG_MIPS_R0 ... KVM_REG_MIPS_R31:
649 		v = (long)vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0];
650 		break;
651 #ifndef CONFIG_CPU_MIPSR6
652 	case KVM_REG_MIPS_HI:
653 		v = (long)vcpu->arch.hi;
654 		break;
655 	case KVM_REG_MIPS_LO:
656 		v = (long)vcpu->arch.lo;
657 		break;
658 #endif
659 	case KVM_REG_MIPS_PC:
660 		v = (long)vcpu->arch.pc;
661 		break;
662 
663 	/* Floating point registers */
664 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
665 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
666 			return -EINVAL;
667 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
668 		/* Odd singles in top of even double when FR=0 */
669 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
670 			v = get_fpr32(&fpu->fpr[idx], 0);
671 		else
672 			v = get_fpr32(&fpu->fpr[idx & ~1], idx & 1);
673 		break;
674 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
675 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
676 			return -EINVAL;
677 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
678 		/* Can't access odd doubles in FR=0 mode */
679 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
680 			return -EINVAL;
681 		v = get_fpr64(&fpu->fpr[idx], 0);
682 		break;
683 	case KVM_REG_MIPS_FCR_IR:
684 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
685 			return -EINVAL;
686 		v = boot_cpu_data.fpu_id;
687 		break;
688 	case KVM_REG_MIPS_FCR_CSR:
689 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
690 			return -EINVAL;
691 		v = fpu->fcr31;
692 		break;
693 
694 	/* MIPS SIMD Architecture (MSA) registers */
695 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
696 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
697 			return -EINVAL;
698 		/* Can't access MSA registers in FR=0 mode */
699 		if (!(kvm_read_c0_guest_status(cop0) & ST0_FR))
700 			return -EINVAL;
701 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
702 #ifdef CONFIG_CPU_LITTLE_ENDIAN
703 		/* least significant byte first */
704 		vs[0] = get_fpr64(&fpu->fpr[idx], 0);
705 		vs[1] = get_fpr64(&fpu->fpr[idx], 1);
706 #else
707 		/* most significant byte first */
708 		vs[0] = get_fpr64(&fpu->fpr[idx], 1);
709 		vs[1] = get_fpr64(&fpu->fpr[idx], 0);
710 #endif
711 		break;
712 	case KVM_REG_MIPS_MSA_IR:
713 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
714 			return -EINVAL;
715 		v = boot_cpu_data.msa_id;
716 		break;
717 	case KVM_REG_MIPS_MSA_CSR:
718 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
719 			return -EINVAL;
720 		v = fpu->msacsr;
721 		break;
722 
723 	/* registers to be handled specially */
724 	default:
725 		ret = kvm_mips_callbacks->get_one_reg(vcpu, reg, &v);
726 		if (ret)
727 			return ret;
728 		break;
729 	}
730 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
731 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
732 
733 		return put_user(v, uaddr64);
734 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
735 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
736 		u32 v32 = (u32)v;
737 
738 		return put_user(v32, uaddr32);
739 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
740 		void __user *uaddr = (void __user *)(long)reg->addr;
741 
742 		return copy_to_user(uaddr, vs, 16) ? -EFAULT : 0;
743 	} else {
744 		return -EINVAL;
745 	}
746 }
747 
748 static int kvm_mips_set_reg(struct kvm_vcpu *vcpu,
749 			    const struct kvm_one_reg *reg)
750 {
751 	struct mips_coproc *cop0 = vcpu->arch.cop0;
752 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
753 	s64 v;
754 	s64 vs[2];
755 	unsigned int idx;
756 
757 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
758 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
759 
760 		if (get_user(v, uaddr64) != 0)
761 			return -EFAULT;
762 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
763 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
764 		s32 v32;
765 
766 		if (get_user(v32, uaddr32) != 0)
767 			return -EFAULT;
768 		v = (s64)v32;
769 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
770 		void __user *uaddr = (void __user *)(long)reg->addr;
771 
772 		return copy_from_user(vs, uaddr, 16) ? -EFAULT : 0;
773 	} else {
774 		return -EINVAL;
775 	}
776 
777 	switch (reg->id) {
778 	/* General purpose registers */
779 	case KVM_REG_MIPS_R0:
780 		/* Silently ignore requests to set $0 */
781 		break;
782 	case KVM_REG_MIPS_R1 ... KVM_REG_MIPS_R31:
783 		vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0] = v;
784 		break;
785 #ifndef CONFIG_CPU_MIPSR6
786 	case KVM_REG_MIPS_HI:
787 		vcpu->arch.hi = v;
788 		break;
789 	case KVM_REG_MIPS_LO:
790 		vcpu->arch.lo = v;
791 		break;
792 #endif
793 	case KVM_REG_MIPS_PC:
794 		vcpu->arch.pc = v;
795 		break;
796 
797 	/* Floating point registers */
798 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
799 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
800 			return -EINVAL;
801 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
802 		/* Odd singles in top of even double when FR=0 */
803 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
804 			set_fpr32(&fpu->fpr[idx], 0, v);
805 		else
806 			set_fpr32(&fpu->fpr[idx & ~1], idx & 1, v);
807 		break;
808 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
809 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
810 			return -EINVAL;
811 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
812 		/* Can't access odd doubles in FR=0 mode */
813 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
814 			return -EINVAL;
815 		set_fpr64(&fpu->fpr[idx], 0, v);
816 		break;
817 	case KVM_REG_MIPS_FCR_IR:
818 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
819 			return -EINVAL;
820 		/* Read-only */
821 		break;
822 	case KVM_REG_MIPS_FCR_CSR:
823 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
824 			return -EINVAL;
825 		fpu->fcr31 = v;
826 		break;
827 
828 	/* MIPS SIMD Architecture (MSA) registers */
829 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
830 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
831 			return -EINVAL;
832 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
833 #ifdef CONFIG_CPU_LITTLE_ENDIAN
834 		/* least significant byte first */
835 		set_fpr64(&fpu->fpr[idx], 0, vs[0]);
836 		set_fpr64(&fpu->fpr[idx], 1, vs[1]);
837 #else
838 		/* most significant byte first */
839 		set_fpr64(&fpu->fpr[idx], 1, vs[0]);
840 		set_fpr64(&fpu->fpr[idx], 0, vs[1]);
841 #endif
842 		break;
843 	case KVM_REG_MIPS_MSA_IR:
844 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
845 			return -EINVAL;
846 		/* Read-only */
847 		break;
848 	case KVM_REG_MIPS_MSA_CSR:
849 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
850 			return -EINVAL;
851 		fpu->msacsr = v;
852 		break;
853 
854 	/* registers to be handled specially */
855 	default:
856 		return kvm_mips_callbacks->set_one_reg(vcpu, reg, v);
857 	}
858 	return 0;
859 }
860 
861 static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
862 				     struct kvm_enable_cap *cap)
863 {
864 	int r = 0;
865 
866 	if (!kvm_vm_ioctl_check_extension(vcpu->kvm, cap->cap))
867 		return -EINVAL;
868 	if (cap->flags)
869 		return -EINVAL;
870 	if (cap->args[0])
871 		return -EINVAL;
872 
873 	switch (cap->cap) {
874 	case KVM_CAP_MIPS_FPU:
875 		vcpu->arch.fpu_enabled = true;
876 		break;
877 	case KVM_CAP_MIPS_MSA:
878 		vcpu->arch.msa_enabled = true;
879 		break;
880 	default:
881 		r = -EINVAL;
882 		break;
883 	}
884 
885 	return r;
886 }
887 
888 long kvm_arch_vcpu_async_ioctl(struct file *filp, unsigned int ioctl,
889 			       unsigned long arg)
890 {
891 	struct kvm_vcpu *vcpu = filp->private_data;
892 	void __user *argp = (void __user *)arg;
893 
894 	if (ioctl == KVM_INTERRUPT) {
895 		struct kvm_mips_interrupt irq;
896 
897 		if (copy_from_user(&irq, argp, sizeof(irq)))
898 			return -EFAULT;
899 		kvm_debug("[%d] %s: irq: %d\n", vcpu->vcpu_id, __func__,
900 			  irq.irq);
901 
902 		return kvm_vcpu_ioctl_interrupt(vcpu, &irq);
903 	}
904 
905 	return -ENOIOCTLCMD;
906 }
907 
908 long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl,
909 			 unsigned long arg)
910 {
911 	struct kvm_vcpu *vcpu = filp->private_data;
912 	void __user *argp = (void __user *)arg;
913 	long r;
914 
915 	vcpu_load(vcpu);
916 
917 	switch (ioctl) {
918 	case KVM_SET_ONE_REG:
919 	case KVM_GET_ONE_REG: {
920 		struct kvm_one_reg reg;
921 
922 		r = -EFAULT;
923 		if (copy_from_user(&reg, argp, sizeof(reg)))
924 			break;
925 		if (ioctl == KVM_SET_ONE_REG)
926 			r = kvm_mips_set_reg(vcpu, &reg);
927 		else
928 			r = kvm_mips_get_reg(vcpu, &reg);
929 		break;
930 	}
931 	case KVM_GET_REG_LIST: {
932 		struct kvm_reg_list __user *user_list = argp;
933 		struct kvm_reg_list reg_list;
934 		unsigned n;
935 
936 		r = -EFAULT;
937 		if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
938 			break;
939 		n = reg_list.n;
940 		reg_list.n = kvm_mips_num_regs(vcpu);
941 		if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
942 			break;
943 		r = -E2BIG;
944 		if (n < reg_list.n)
945 			break;
946 		r = kvm_mips_copy_reg_indices(vcpu, user_list->reg);
947 		break;
948 	}
949 	case KVM_ENABLE_CAP: {
950 		struct kvm_enable_cap cap;
951 
952 		r = -EFAULT;
953 		if (copy_from_user(&cap, argp, sizeof(cap)))
954 			break;
955 		r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
956 		break;
957 	}
958 	default:
959 		r = -ENOIOCTLCMD;
960 	}
961 
962 	vcpu_put(vcpu);
963 	return r;
964 }
965 
966 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
967 {
968 
969 }
970 
971 int kvm_arch_flush_remote_tlb(struct kvm *kvm)
972 {
973 	kvm_mips_callbacks->prepare_flush_shadow(kvm);
974 	return 1;
975 }
976 
977 void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
978 					const struct kvm_memory_slot *memslot)
979 {
980 	kvm_flush_remote_tlbs(kvm);
981 }
982 
983 long kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
984 {
985 	long r;
986 
987 	switch (ioctl) {
988 	default:
989 		r = -ENOIOCTLCMD;
990 	}
991 
992 	return r;
993 }
994 
995 int kvm_arch_init(void *opaque)
996 {
997 	if (kvm_mips_callbacks) {
998 		kvm_err("kvm: module already exists\n");
999 		return -EEXIST;
1000 	}
1001 
1002 	return kvm_mips_emulation_init(&kvm_mips_callbacks);
1003 }
1004 
1005 void kvm_arch_exit(void)
1006 {
1007 	kvm_mips_callbacks = NULL;
1008 }
1009 
1010 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
1011 				  struct kvm_sregs *sregs)
1012 {
1013 	return -ENOIOCTLCMD;
1014 }
1015 
1016 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
1017 				  struct kvm_sregs *sregs)
1018 {
1019 	return -ENOIOCTLCMD;
1020 }
1021 
1022 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
1023 {
1024 }
1025 
1026 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1027 {
1028 	return -ENOIOCTLCMD;
1029 }
1030 
1031 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1032 {
1033 	return -ENOIOCTLCMD;
1034 }
1035 
1036 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
1037 {
1038 	return VM_FAULT_SIGBUS;
1039 }
1040 
1041 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
1042 {
1043 	int r;
1044 
1045 	switch (ext) {
1046 	case KVM_CAP_ONE_REG:
1047 	case KVM_CAP_ENABLE_CAP:
1048 	case KVM_CAP_READONLY_MEM:
1049 	case KVM_CAP_SYNC_MMU:
1050 	case KVM_CAP_IMMEDIATE_EXIT:
1051 		r = 1;
1052 		break;
1053 	case KVM_CAP_NR_VCPUS:
1054 		r = num_online_cpus();
1055 		break;
1056 	case KVM_CAP_MAX_VCPUS:
1057 		r = KVM_MAX_VCPUS;
1058 		break;
1059 	case KVM_CAP_MAX_VCPU_ID:
1060 		r = KVM_MAX_VCPU_ID;
1061 		break;
1062 	case KVM_CAP_MIPS_FPU:
1063 		/* We don't handle systems with inconsistent cpu_has_fpu */
1064 		r = !!raw_cpu_has_fpu;
1065 		break;
1066 	case KVM_CAP_MIPS_MSA:
1067 		/*
1068 		 * We don't support MSA vector partitioning yet:
1069 		 * 1) It would require explicit support which can't be tested
1070 		 *    yet due to lack of support in current hardware.
1071 		 * 2) It extends the state that would need to be saved/restored
1072 		 *    by e.g. QEMU for migration.
1073 		 *
1074 		 * When vector partitioning hardware becomes available, support
1075 		 * could be added by requiring a flag when enabling
1076 		 * KVM_CAP_MIPS_MSA capability to indicate that userland knows
1077 		 * to save/restore the appropriate extra state.
1078 		 */
1079 		r = cpu_has_msa && !(boot_cpu_data.msa_id & MSA_IR_WRPF);
1080 		break;
1081 	default:
1082 		r = kvm_mips_callbacks->check_extension(kvm, ext);
1083 		break;
1084 	}
1085 	return r;
1086 }
1087 
1088 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
1089 {
1090 	return kvm_mips_pending_timer(vcpu) ||
1091 		kvm_read_c0_guest_cause(vcpu->arch.cop0) & C_TI;
1092 }
1093 
1094 int kvm_arch_vcpu_dump_regs(struct kvm_vcpu *vcpu)
1095 {
1096 	int i;
1097 	struct mips_coproc *cop0;
1098 
1099 	if (!vcpu)
1100 		return -1;
1101 
1102 	kvm_debug("VCPU Register Dump:\n");
1103 	kvm_debug("\tpc = 0x%08lx\n", vcpu->arch.pc);
1104 	kvm_debug("\texceptions: %08lx\n", vcpu->arch.pending_exceptions);
1105 
1106 	for (i = 0; i < 32; i += 4) {
1107 		kvm_debug("\tgpr%02d: %08lx %08lx %08lx %08lx\n", i,
1108 		       vcpu->arch.gprs[i],
1109 		       vcpu->arch.gprs[i + 1],
1110 		       vcpu->arch.gprs[i + 2], vcpu->arch.gprs[i + 3]);
1111 	}
1112 	kvm_debug("\thi: 0x%08lx\n", vcpu->arch.hi);
1113 	kvm_debug("\tlo: 0x%08lx\n", vcpu->arch.lo);
1114 
1115 	cop0 = vcpu->arch.cop0;
1116 	kvm_debug("\tStatus: 0x%08x, Cause: 0x%08x\n",
1117 		  kvm_read_c0_guest_status(cop0),
1118 		  kvm_read_c0_guest_cause(cop0));
1119 
1120 	kvm_debug("\tEPC: 0x%08lx\n", kvm_read_c0_guest_epc(cop0));
1121 
1122 	return 0;
1123 }
1124 
1125 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1126 {
1127 	int i;
1128 
1129 	vcpu_load(vcpu);
1130 
1131 	for (i = 1; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1132 		vcpu->arch.gprs[i] = regs->gpr[i];
1133 	vcpu->arch.gprs[0] = 0; /* zero is special, and cannot be set. */
1134 	vcpu->arch.hi = regs->hi;
1135 	vcpu->arch.lo = regs->lo;
1136 	vcpu->arch.pc = regs->pc;
1137 
1138 	vcpu_put(vcpu);
1139 	return 0;
1140 }
1141 
1142 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1143 {
1144 	int i;
1145 
1146 	vcpu_load(vcpu);
1147 
1148 	for (i = 0; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1149 		regs->gpr[i] = vcpu->arch.gprs[i];
1150 
1151 	regs->hi = vcpu->arch.hi;
1152 	regs->lo = vcpu->arch.lo;
1153 	regs->pc = vcpu->arch.pc;
1154 
1155 	vcpu_put(vcpu);
1156 	return 0;
1157 }
1158 
1159 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
1160 				  struct kvm_translation *tr)
1161 {
1162 	return 0;
1163 }
1164 
1165 static void kvm_mips_set_c0_status(void)
1166 {
1167 	u32 status = read_c0_status();
1168 
1169 	if (cpu_has_dsp)
1170 		status |= (ST0_MX);
1171 
1172 	write_c0_status(status);
1173 	ehb();
1174 }
1175 
1176 /*
1177  * Return value is in the form (errcode<<2 | RESUME_FLAG_HOST | RESUME_FLAG_NV)
1178  */
1179 int kvm_mips_handle_exit(struct kvm_vcpu *vcpu)
1180 {
1181 	struct kvm_run *run = vcpu->run;
1182 	u32 cause = vcpu->arch.host_cp0_cause;
1183 	u32 exccode = (cause >> CAUSEB_EXCCODE) & 0x1f;
1184 	u32 __user *opc = (u32 __user *) vcpu->arch.pc;
1185 	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
1186 	enum emulation_result er = EMULATE_DONE;
1187 	u32 inst;
1188 	int ret = RESUME_GUEST;
1189 
1190 	vcpu->mode = OUTSIDE_GUEST_MODE;
1191 
1192 	/* Set a default exit reason */
1193 	run->exit_reason = KVM_EXIT_UNKNOWN;
1194 	run->ready_for_interrupt_injection = 1;
1195 
1196 	/*
1197 	 * Set the appropriate status bits based on host CPU features,
1198 	 * before we hit the scheduler
1199 	 */
1200 	kvm_mips_set_c0_status();
1201 
1202 	local_irq_enable();
1203 
1204 	kvm_debug("kvm_mips_handle_exit: cause: %#x, PC: %p, kvm_run: %p, kvm_vcpu: %p\n",
1205 			cause, opc, run, vcpu);
1206 	trace_kvm_exit(vcpu, exccode);
1207 
1208 	switch (exccode) {
1209 	case EXCCODE_INT:
1210 		kvm_debug("[%d]EXCCODE_INT @ %p\n", vcpu->vcpu_id, opc);
1211 
1212 		++vcpu->stat.int_exits;
1213 
1214 		if (need_resched())
1215 			cond_resched();
1216 
1217 		ret = RESUME_GUEST;
1218 		break;
1219 
1220 	case EXCCODE_CPU:
1221 		kvm_debug("EXCCODE_CPU: @ PC: %p\n", opc);
1222 
1223 		++vcpu->stat.cop_unusable_exits;
1224 		ret = kvm_mips_callbacks->handle_cop_unusable(vcpu);
1225 		/* XXXKYMA: Might need to return to user space */
1226 		if (run->exit_reason == KVM_EXIT_IRQ_WINDOW_OPEN)
1227 			ret = RESUME_HOST;
1228 		break;
1229 
1230 	case EXCCODE_MOD:
1231 		++vcpu->stat.tlbmod_exits;
1232 		ret = kvm_mips_callbacks->handle_tlb_mod(vcpu);
1233 		break;
1234 
1235 	case EXCCODE_TLBS:
1236 		kvm_debug("TLB ST fault:  cause %#x, status %#x, PC: %p, BadVaddr: %#lx\n",
1237 			  cause, kvm_read_c0_guest_status(vcpu->arch.cop0), opc,
1238 			  badvaddr);
1239 
1240 		++vcpu->stat.tlbmiss_st_exits;
1241 		ret = kvm_mips_callbacks->handle_tlb_st_miss(vcpu);
1242 		break;
1243 
1244 	case EXCCODE_TLBL:
1245 		kvm_debug("TLB LD fault: cause %#x, PC: %p, BadVaddr: %#lx\n",
1246 			  cause, opc, badvaddr);
1247 
1248 		++vcpu->stat.tlbmiss_ld_exits;
1249 		ret = kvm_mips_callbacks->handle_tlb_ld_miss(vcpu);
1250 		break;
1251 
1252 	case EXCCODE_ADES:
1253 		++vcpu->stat.addrerr_st_exits;
1254 		ret = kvm_mips_callbacks->handle_addr_err_st(vcpu);
1255 		break;
1256 
1257 	case EXCCODE_ADEL:
1258 		++vcpu->stat.addrerr_ld_exits;
1259 		ret = kvm_mips_callbacks->handle_addr_err_ld(vcpu);
1260 		break;
1261 
1262 	case EXCCODE_SYS:
1263 		++vcpu->stat.syscall_exits;
1264 		ret = kvm_mips_callbacks->handle_syscall(vcpu);
1265 		break;
1266 
1267 	case EXCCODE_RI:
1268 		++vcpu->stat.resvd_inst_exits;
1269 		ret = kvm_mips_callbacks->handle_res_inst(vcpu);
1270 		break;
1271 
1272 	case EXCCODE_BP:
1273 		++vcpu->stat.break_inst_exits;
1274 		ret = kvm_mips_callbacks->handle_break(vcpu);
1275 		break;
1276 
1277 	case EXCCODE_TR:
1278 		++vcpu->stat.trap_inst_exits;
1279 		ret = kvm_mips_callbacks->handle_trap(vcpu);
1280 		break;
1281 
1282 	case EXCCODE_MSAFPE:
1283 		++vcpu->stat.msa_fpe_exits;
1284 		ret = kvm_mips_callbacks->handle_msa_fpe(vcpu);
1285 		break;
1286 
1287 	case EXCCODE_FPE:
1288 		++vcpu->stat.fpe_exits;
1289 		ret = kvm_mips_callbacks->handle_fpe(vcpu);
1290 		break;
1291 
1292 	case EXCCODE_MSADIS:
1293 		++vcpu->stat.msa_disabled_exits;
1294 		ret = kvm_mips_callbacks->handle_msa_disabled(vcpu);
1295 		break;
1296 
1297 	case EXCCODE_GE:
1298 		/* defer exit accounting to handler */
1299 		ret = kvm_mips_callbacks->handle_guest_exit(vcpu);
1300 		break;
1301 
1302 	default:
1303 		if (cause & CAUSEF_BD)
1304 			opc += 1;
1305 		inst = 0;
1306 		kvm_get_badinstr(opc, vcpu, &inst);
1307 		kvm_err("Exception Code: %d, not yet handled, @ PC: %p, inst: 0x%08x  BadVaddr: %#lx Status: %#x\n",
1308 			exccode, opc, inst, badvaddr,
1309 			kvm_read_c0_guest_status(vcpu->arch.cop0));
1310 		kvm_arch_vcpu_dump_regs(vcpu);
1311 		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1312 		ret = RESUME_HOST;
1313 		break;
1314 
1315 	}
1316 
1317 	local_irq_disable();
1318 
1319 	if (ret == RESUME_GUEST)
1320 		kvm_vz_acquire_htimer(vcpu);
1321 
1322 	if (er == EMULATE_DONE && !(ret & RESUME_HOST))
1323 		kvm_mips_deliver_interrupts(vcpu, cause);
1324 
1325 	if (!(ret & RESUME_HOST)) {
1326 		/* Only check for signals if not already exiting to userspace */
1327 		if (signal_pending(current)) {
1328 			run->exit_reason = KVM_EXIT_INTR;
1329 			ret = (-EINTR << 2) | RESUME_HOST;
1330 			++vcpu->stat.signal_exits;
1331 			trace_kvm_exit(vcpu, KVM_TRACE_EXIT_SIGNAL);
1332 		}
1333 	}
1334 
1335 	if (ret == RESUME_GUEST) {
1336 		trace_kvm_reenter(vcpu);
1337 
1338 		/*
1339 		 * Make sure the read of VCPU requests in vcpu_reenter()
1340 		 * callback is not reordered ahead of the write to vcpu->mode,
1341 		 * or we could miss a TLB flush request while the requester sees
1342 		 * the VCPU as outside of guest mode and not needing an IPI.
1343 		 */
1344 		smp_store_mb(vcpu->mode, IN_GUEST_MODE);
1345 
1346 		kvm_mips_callbacks->vcpu_reenter(vcpu);
1347 
1348 		/*
1349 		 * If FPU / MSA are enabled (i.e. the guest's FPU / MSA context
1350 		 * is live), restore FCR31 / MSACSR.
1351 		 *
1352 		 * This should be before returning to the guest exception
1353 		 * vector, as it may well cause an [MSA] FP exception if there
1354 		 * are pending exception bits unmasked. (see
1355 		 * kvm_mips_csr_die_notifier() for how that is handled).
1356 		 */
1357 		if (kvm_mips_guest_has_fpu(&vcpu->arch) &&
1358 		    read_c0_status() & ST0_CU1)
1359 			__kvm_restore_fcsr(&vcpu->arch);
1360 
1361 		if (kvm_mips_guest_has_msa(&vcpu->arch) &&
1362 		    read_c0_config5() & MIPS_CONF5_MSAEN)
1363 			__kvm_restore_msacsr(&vcpu->arch);
1364 	}
1365 	return ret;
1366 }
1367 
1368 /* Enable FPU for guest and restore context */
1369 void kvm_own_fpu(struct kvm_vcpu *vcpu)
1370 {
1371 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1372 	unsigned int sr, cfg5;
1373 
1374 	preempt_disable();
1375 
1376 	sr = kvm_read_c0_guest_status(cop0);
1377 
1378 	/*
1379 	 * If MSA state is already live, it is undefined how it interacts with
1380 	 * FR=0 FPU state, and we don't want to hit reserved instruction
1381 	 * exceptions trying to save the MSA state later when CU=1 && FR=1, so
1382 	 * play it safe and save it first.
1383 	 */
1384 	if (cpu_has_msa && sr & ST0_CU1 && !(sr & ST0_FR) &&
1385 	    vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA)
1386 		kvm_lose_fpu(vcpu);
1387 
1388 	/*
1389 	 * Enable FPU for guest
1390 	 * We set FR and FRE according to guest context
1391 	 */
1392 	change_c0_status(ST0_CU1 | ST0_FR, sr);
1393 	if (cpu_has_fre) {
1394 		cfg5 = kvm_read_c0_guest_config5(cop0);
1395 		change_c0_config5(MIPS_CONF5_FRE, cfg5);
1396 	}
1397 	enable_fpu_hazard();
1398 
1399 	/* If guest FPU state not active, restore it now */
1400 	if (!(vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU)) {
1401 		__kvm_restore_fpu(&vcpu->arch);
1402 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1403 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_FPU);
1404 	} else {
1405 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_FPU);
1406 	}
1407 
1408 	preempt_enable();
1409 }
1410 
1411 #ifdef CONFIG_CPU_HAS_MSA
1412 /* Enable MSA for guest and restore context */
1413 void kvm_own_msa(struct kvm_vcpu *vcpu)
1414 {
1415 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1416 	unsigned int sr, cfg5;
1417 
1418 	preempt_disable();
1419 
1420 	/*
1421 	 * Enable FPU if enabled in guest, since we're restoring FPU context
1422 	 * anyway. We set FR and FRE according to guest context.
1423 	 */
1424 	if (kvm_mips_guest_has_fpu(&vcpu->arch)) {
1425 		sr = kvm_read_c0_guest_status(cop0);
1426 
1427 		/*
1428 		 * If FR=0 FPU state is already live, it is undefined how it
1429 		 * interacts with MSA state, so play it safe and save it first.
1430 		 */
1431 		if (!(sr & ST0_FR) &&
1432 		    (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU |
1433 				KVM_MIPS_AUX_MSA)) == KVM_MIPS_AUX_FPU)
1434 			kvm_lose_fpu(vcpu);
1435 
1436 		change_c0_status(ST0_CU1 | ST0_FR, sr);
1437 		if (sr & ST0_CU1 && cpu_has_fre) {
1438 			cfg5 = kvm_read_c0_guest_config5(cop0);
1439 			change_c0_config5(MIPS_CONF5_FRE, cfg5);
1440 		}
1441 	}
1442 
1443 	/* Enable MSA for guest */
1444 	set_c0_config5(MIPS_CONF5_MSAEN);
1445 	enable_fpu_hazard();
1446 
1447 	switch (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA)) {
1448 	case KVM_MIPS_AUX_FPU:
1449 		/*
1450 		 * Guest FPU state already loaded, only restore upper MSA state
1451 		 */
1452 		__kvm_restore_msa_upper(&vcpu->arch);
1453 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1454 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_MSA);
1455 		break;
1456 	case 0:
1457 		/* Neither FPU or MSA already active, restore full MSA state */
1458 		__kvm_restore_msa(&vcpu->arch);
1459 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1460 		if (kvm_mips_guest_has_fpu(&vcpu->arch))
1461 			vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1462 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE,
1463 			      KVM_TRACE_AUX_FPU_MSA);
1464 		break;
1465 	default:
1466 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_MSA);
1467 		break;
1468 	}
1469 
1470 	preempt_enable();
1471 }
1472 #endif
1473 
1474 /* Drop FPU & MSA without saving it */
1475 void kvm_drop_fpu(struct kvm_vcpu *vcpu)
1476 {
1477 	preempt_disable();
1478 	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1479 		disable_msa();
1480 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_MSA);
1481 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_MSA;
1482 	}
1483 	if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1484 		clear_c0_status(ST0_CU1 | ST0_FR);
1485 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_FPU);
1486 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1487 	}
1488 	preempt_enable();
1489 }
1490 
1491 /* Save and disable FPU & MSA */
1492 void kvm_lose_fpu(struct kvm_vcpu *vcpu)
1493 {
1494 	/*
1495 	 * With T&E, FPU & MSA get disabled in root context (hardware) when it
1496 	 * is disabled in guest context (software), but the register state in
1497 	 * the hardware may still be in use.
1498 	 * This is why we explicitly re-enable the hardware before saving.
1499 	 */
1500 
1501 	preempt_disable();
1502 	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1503 		__kvm_save_msa(&vcpu->arch);
1504 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU_MSA);
1505 
1506 		/* Disable MSA & FPU */
1507 		disable_msa();
1508 		if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1509 			clear_c0_status(ST0_CU1 | ST0_FR);
1510 			disable_fpu_hazard();
1511 		}
1512 		vcpu->arch.aux_inuse &= ~(KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA);
1513 	} else if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1514 		__kvm_save_fpu(&vcpu->arch);
1515 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1516 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU);
1517 
1518 		/* Disable FPU */
1519 		clear_c0_status(ST0_CU1 | ST0_FR);
1520 		disable_fpu_hazard();
1521 	}
1522 	preempt_enable();
1523 }
1524 
1525 /*
1526  * Step over a specific ctc1 to FCSR and a specific ctcmsa to MSACSR which are
1527  * used to restore guest FCSR/MSACSR state and may trigger a "harmless" FP/MSAFP
1528  * exception if cause bits are set in the value being written.
1529  */
1530 static int kvm_mips_csr_die_notify(struct notifier_block *self,
1531 				   unsigned long cmd, void *ptr)
1532 {
1533 	struct die_args *args = (struct die_args *)ptr;
1534 	struct pt_regs *regs = args->regs;
1535 	unsigned long pc;
1536 
1537 	/* Only interested in FPE and MSAFPE */
1538 	if (cmd != DIE_FP && cmd != DIE_MSAFP)
1539 		return NOTIFY_DONE;
1540 
1541 	/* Return immediately if guest context isn't active */
1542 	if (!(current->flags & PF_VCPU))
1543 		return NOTIFY_DONE;
1544 
1545 	/* Should never get here from user mode */
1546 	BUG_ON(user_mode(regs));
1547 
1548 	pc = instruction_pointer(regs);
1549 	switch (cmd) {
1550 	case DIE_FP:
1551 		/* match 2nd instruction in __kvm_restore_fcsr */
1552 		if (pc != (unsigned long)&__kvm_restore_fcsr + 4)
1553 			return NOTIFY_DONE;
1554 		break;
1555 	case DIE_MSAFP:
1556 		/* match 2nd/3rd instruction in __kvm_restore_msacsr */
1557 		if (!cpu_has_msa ||
1558 		    pc < (unsigned long)&__kvm_restore_msacsr + 4 ||
1559 		    pc > (unsigned long)&__kvm_restore_msacsr + 8)
1560 			return NOTIFY_DONE;
1561 		break;
1562 	}
1563 
1564 	/* Move PC forward a little and continue executing */
1565 	instruction_pointer(regs) += 4;
1566 
1567 	return NOTIFY_STOP;
1568 }
1569 
1570 static struct notifier_block kvm_mips_csr_die_notifier = {
1571 	.notifier_call = kvm_mips_csr_die_notify,
1572 };
1573 
1574 static u32 kvm_default_priority_to_irq[MIPS_EXC_MAX] = {
1575 	[MIPS_EXC_INT_TIMER] = C_IRQ5,
1576 	[MIPS_EXC_INT_IO_1]  = C_IRQ0,
1577 	[MIPS_EXC_INT_IPI_1] = C_IRQ1,
1578 	[MIPS_EXC_INT_IPI_2] = C_IRQ2,
1579 };
1580 
1581 static u32 kvm_loongson3_priority_to_irq[MIPS_EXC_MAX] = {
1582 	[MIPS_EXC_INT_TIMER] = C_IRQ5,
1583 	[MIPS_EXC_INT_IO_1]  = C_IRQ0,
1584 	[MIPS_EXC_INT_IO_2]  = C_IRQ1,
1585 	[MIPS_EXC_INT_IPI_1] = C_IRQ4,
1586 };
1587 
1588 u32 *kvm_priority_to_irq = kvm_default_priority_to_irq;
1589 
1590 u32 kvm_irq_to_priority(u32 irq)
1591 {
1592 	int i;
1593 
1594 	for (i = MIPS_EXC_INT_TIMER; i < MIPS_EXC_MAX; i++) {
1595 		if (kvm_priority_to_irq[i] == (1 << (irq + 8)))
1596 			return i;
1597 	}
1598 
1599 	return MIPS_EXC_MAX;
1600 }
1601 
1602 static int __init kvm_mips_init(void)
1603 {
1604 	int ret;
1605 
1606 	if (cpu_has_mmid) {
1607 		pr_warn("KVM does not yet support MMIDs. KVM Disabled\n");
1608 		return -EOPNOTSUPP;
1609 	}
1610 
1611 	ret = kvm_mips_entry_setup();
1612 	if (ret)
1613 		return ret;
1614 
1615 	ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
1616 
1617 	if (ret)
1618 		return ret;
1619 
1620 	if (boot_cpu_type() == CPU_LOONGSON64)
1621 		kvm_priority_to_irq = kvm_loongson3_priority_to_irq;
1622 
1623 	register_die_notifier(&kvm_mips_csr_die_notifier);
1624 
1625 	return 0;
1626 }
1627 
1628 static void __exit kvm_mips_exit(void)
1629 {
1630 	kvm_exit();
1631 
1632 	unregister_die_notifier(&kvm_mips_csr_die_notifier);
1633 }
1634 
1635 module_init(kvm_mips_init);
1636 module_exit(kvm_mips_exit);
1637 
1638 EXPORT_TRACEPOINT_SYMBOL(kvm_exit);
1639