xref: /linux/arch/mips/kvm/mips.c (revision b77e0ce62d63a761ffb7f7245a215a49f5921c2f)
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 #include "commpage.h"
34 
35 #define CREATE_TRACE_POINTS
36 #include "trace.h"
37 
38 #ifndef VECTORSPACING
39 #define VECTORSPACING 0x100	/* for EI/VI mode */
40 #endif
41 
42 struct kvm_stats_debugfs_item debugfs_entries[] = {
43 	VCPU_STAT("wait", wait_exits),
44 	VCPU_STAT("cache", cache_exits),
45 	VCPU_STAT("signal", signal_exits),
46 	VCPU_STAT("interrupt", int_exits),
47 	VCPU_STAT("cop_unusable", cop_unusable_exits),
48 	VCPU_STAT("tlbmod", tlbmod_exits),
49 	VCPU_STAT("tlbmiss_ld", tlbmiss_ld_exits),
50 	VCPU_STAT("tlbmiss_st", tlbmiss_st_exits),
51 	VCPU_STAT("addrerr_st", addrerr_st_exits),
52 	VCPU_STAT("addrerr_ld", addrerr_ld_exits),
53 	VCPU_STAT("syscall", syscall_exits),
54 	VCPU_STAT("resvd_inst", resvd_inst_exits),
55 	VCPU_STAT("break_inst", break_inst_exits),
56 	VCPU_STAT("trap_inst", trap_inst_exits),
57 	VCPU_STAT("msa_fpe", msa_fpe_exits),
58 	VCPU_STAT("fpe", fpe_exits),
59 	VCPU_STAT("msa_disabled", msa_disabled_exits),
60 	VCPU_STAT("flush_dcache", flush_dcache_exits),
61 #ifdef CONFIG_KVM_MIPS_VZ
62 	VCPU_STAT("vz_gpsi", vz_gpsi_exits),
63 	VCPU_STAT("vz_gsfc", vz_gsfc_exits),
64 	VCPU_STAT("vz_hc", vz_hc_exits),
65 	VCPU_STAT("vz_grr", vz_grr_exits),
66 	VCPU_STAT("vz_gva", vz_gva_exits),
67 	VCPU_STAT("vz_ghfc", vz_ghfc_exits),
68 	VCPU_STAT("vz_gpa", vz_gpa_exits),
69 	VCPU_STAT("vz_resvd", vz_resvd_exits),
70 #ifdef CONFIG_CPU_LOONGSON64
71 	VCPU_STAT("vz_cpucfg", vz_cpucfg_exits),
72 #endif
73 #endif
74 	VCPU_STAT("halt_successful_poll", halt_successful_poll),
75 	VCPU_STAT("halt_attempted_poll", halt_attempted_poll),
76 	VCPU_STAT("halt_poll_invalid", halt_poll_invalid),
77 	VCPU_STAT("halt_wakeup", halt_wakeup),
78 	VCPU_STAT("halt_poll_success_ns", halt_poll_success_ns),
79 	VCPU_STAT("halt_poll_fail_ns", halt_poll_fail_ns),
80 	{NULL}
81 };
82 
83 bool kvm_trace_guest_mode_change;
84 
85 int kvm_guest_mode_change_trace_reg(void)
86 {
87 	kvm_trace_guest_mode_change = true;
88 	return 0;
89 }
90 
91 void kvm_guest_mode_change_trace_unreg(void)
92 {
93 	kvm_trace_guest_mode_change = false;
94 }
95 
96 /*
97  * XXXKYMA: We are simulatoring a processor that has the WII bit set in
98  * Config7, so we are "runnable" if interrupts are pending
99  */
100 int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
101 {
102 	return !!(vcpu->arch.pending_exceptions);
103 }
104 
105 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
106 {
107 	return false;
108 }
109 
110 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
111 {
112 	return 1;
113 }
114 
115 int kvm_arch_hardware_enable(void)
116 {
117 	return kvm_mips_callbacks->hardware_enable();
118 }
119 
120 void kvm_arch_hardware_disable(void)
121 {
122 	kvm_mips_callbacks->hardware_disable();
123 }
124 
125 int kvm_arch_hardware_setup(void *opaque)
126 {
127 	return 0;
128 }
129 
130 int kvm_arch_check_processor_compat(void *opaque)
131 {
132 	return 0;
133 }
134 
135 extern void kvm_init_loongson_ipi(struct kvm *kvm);
136 
137 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
138 {
139 	switch (type) {
140 	case KVM_VM_MIPS_AUTO:
141 		break;
142 #ifdef CONFIG_KVM_MIPS_VZ
143 	case KVM_VM_MIPS_VZ:
144 #else
145 	case KVM_VM_MIPS_TE:
146 #endif
147 		break;
148 	default:
149 		/* Unsupported KVM type */
150 		return -EINVAL;
151 	}
152 
153 	/* Allocate page table to map GPA -> RPA */
154 	kvm->arch.gpa_mm.pgd = kvm_pgd_alloc();
155 	if (!kvm->arch.gpa_mm.pgd)
156 		return -ENOMEM;
157 
158 #ifdef CONFIG_CPU_LOONGSON64
159 	kvm_init_loongson_ipi(kvm);
160 #endif
161 
162 	return 0;
163 }
164 
165 void kvm_mips_free_vcpus(struct kvm *kvm)
166 {
167 	unsigned int i;
168 	struct kvm_vcpu *vcpu;
169 
170 	kvm_for_each_vcpu(i, vcpu, kvm) {
171 		kvm_vcpu_destroy(vcpu);
172 	}
173 
174 	mutex_lock(&kvm->lock);
175 
176 	for (i = 0; i < atomic_read(&kvm->online_vcpus); i++)
177 		kvm->vcpus[i] = NULL;
178 
179 	atomic_set(&kvm->online_vcpus, 0);
180 
181 	mutex_unlock(&kvm->lock);
182 }
183 
184 static void kvm_mips_free_gpa_pt(struct kvm *kvm)
185 {
186 	/* It should always be safe to remove after flushing the whole range */
187 	WARN_ON(!kvm_mips_flush_gpa_pt(kvm, 0, ~0));
188 	pgd_free(NULL, kvm->arch.gpa_mm.pgd);
189 }
190 
191 void kvm_arch_destroy_vm(struct kvm *kvm)
192 {
193 	kvm_mips_free_vcpus(kvm);
194 	kvm_mips_free_gpa_pt(kvm);
195 }
196 
197 long kvm_arch_dev_ioctl(struct file *filp, unsigned int ioctl,
198 			unsigned long arg)
199 {
200 	return -ENOIOCTLCMD;
201 }
202 
203 void kvm_arch_flush_shadow_all(struct kvm *kvm)
204 {
205 	/* Flush whole GPA */
206 	kvm_mips_flush_gpa_pt(kvm, 0, ~0);
207 
208 	/* Let implementation do the rest */
209 	kvm_mips_callbacks->flush_shadow_all(kvm);
210 }
211 
212 void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
213 				   struct kvm_memory_slot *slot)
214 {
215 	/*
216 	 * The slot has been made invalid (ready for moving or deletion), so we
217 	 * need to ensure that it can no longer be accessed by any guest VCPUs.
218 	 */
219 
220 	spin_lock(&kvm->mmu_lock);
221 	/* Flush slot from GPA */
222 	kvm_mips_flush_gpa_pt(kvm, slot->base_gfn,
223 			      slot->base_gfn + slot->npages - 1);
224 	/* Let implementation do the rest */
225 	kvm_mips_callbacks->flush_shadow_memslot(kvm, slot);
226 	spin_unlock(&kvm->mmu_lock);
227 }
228 
229 int kvm_arch_prepare_memory_region(struct kvm *kvm,
230 				   struct kvm_memory_slot *memslot,
231 				   const struct kvm_userspace_memory_region *mem,
232 				   enum kvm_mr_change change)
233 {
234 	return 0;
235 }
236 
237 void kvm_arch_commit_memory_region(struct kvm *kvm,
238 				   const struct kvm_userspace_memory_region *mem,
239 				   struct kvm_memory_slot *old,
240 				   const struct kvm_memory_slot *new,
241 				   enum kvm_mr_change change)
242 {
243 	int needs_flush;
244 
245 	kvm_debug("%s: kvm: %p slot: %d, GPA: %llx, size: %llx, QVA: %llx\n",
246 		  __func__, kvm, mem->slot, mem->guest_phys_addr,
247 		  mem->memory_size, mem->userspace_addr);
248 
249 	/*
250 	 * If dirty page logging is enabled, write protect all pages in the slot
251 	 * ready for dirty logging.
252 	 *
253 	 * There is no need to do this in any of the following cases:
254 	 * CREATE:	No dirty mappings will already exist.
255 	 * MOVE/DELETE:	The old mappings will already have been cleaned up by
256 	 *		kvm_arch_flush_shadow_memslot()
257 	 */
258 	if (change == KVM_MR_FLAGS_ONLY &&
259 	    (!(old->flags & KVM_MEM_LOG_DIRTY_PAGES) &&
260 	     new->flags & KVM_MEM_LOG_DIRTY_PAGES)) {
261 		spin_lock(&kvm->mmu_lock);
262 		/* Write protect GPA page table entries */
263 		needs_flush = kvm_mips_mkclean_gpa_pt(kvm, new->base_gfn,
264 					new->base_gfn + new->npages - 1);
265 		/* Let implementation do the rest */
266 		if (needs_flush)
267 			kvm_mips_callbacks->flush_shadow_memslot(kvm, new);
268 		spin_unlock(&kvm->mmu_lock);
269 	}
270 }
271 
272 static inline void dump_handler(const char *symbol, void *start, void *end)
273 {
274 	u32 *p;
275 
276 	pr_debug("LEAF(%s)\n", symbol);
277 
278 	pr_debug("\t.set push\n");
279 	pr_debug("\t.set noreorder\n");
280 
281 	for (p = start; p < (u32 *)end; ++p)
282 		pr_debug("\t.word\t0x%08x\t\t# %p\n", *p, p);
283 
284 	pr_debug("\t.set\tpop\n");
285 
286 	pr_debug("\tEND(%s)\n", symbol);
287 }
288 
289 /* low level hrtimer wake routine */
290 static enum hrtimer_restart kvm_mips_comparecount_wakeup(struct hrtimer *timer)
291 {
292 	struct kvm_vcpu *vcpu;
293 
294 	vcpu = container_of(timer, struct kvm_vcpu, arch.comparecount_timer);
295 
296 	kvm_mips_callbacks->queue_timer_int(vcpu);
297 
298 	vcpu->arch.wait = 0;
299 	rcuwait_wake_up(&vcpu->wait);
300 
301 	return kvm_mips_count_timeout(vcpu);
302 }
303 
304 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
305 {
306 	return 0;
307 }
308 
309 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
310 {
311 	int err, size;
312 	void *gebase, *p, *handler, *refill_start, *refill_end;
313 	int i;
314 
315 	kvm_debug("kvm @ %p: create cpu %d at %p\n",
316 		  vcpu->kvm, vcpu->vcpu_id, vcpu);
317 
318 	err = kvm_mips_callbacks->vcpu_init(vcpu);
319 	if (err)
320 		return err;
321 
322 	hrtimer_init(&vcpu->arch.comparecount_timer, CLOCK_MONOTONIC,
323 		     HRTIMER_MODE_REL);
324 	vcpu->arch.comparecount_timer.function = kvm_mips_comparecount_wakeup;
325 
326 	/*
327 	 * Allocate space for host mode exception handlers that handle
328 	 * guest mode exits
329 	 */
330 	if (cpu_has_veic || cpu_has_vint)
331 		size = 0x200 + VECTORSPACING * 64;
332 	else
333 		size = 0x4000;
334 
335 	gebase = kzalloc(ALIGN(size, PAGE_SIZE), GFP_KERNEL);
336 
337 	if (!gebase) {
338 		err = -ENOMEM;
339 		goto out_uninit_vcpu;
340 	}
341 	kvm_debug("Allocated %d bytes for KVM Exception Handlers @ %p\n",
342 		  ALIGN(size, PAGE_SIZE), gebase);
343 
344 	/*
345 	 * Check new ebase actually fits in CP0_EBase. The lack of a write gate
346 	 * limits us to the low 512MB of physical address space. If the memory
347 	 * we allocate is out of range, just give up now.
348 	 */
349 	if (!cpu_has_ebase_wg && virt_to_phys(gebase) >= 0x20000000) {
350 		kvm_err("CP0_EBase.WG required for guest exception base %pK\n",
351 			gebase);
352 		err = -ENOMEM;
353 		goto out_free_gebase;
354 	}
355 
356 	/* Save new ebase */
357 	vcpu->arch.guest_ebase = gebase;
358 
359 	/* Build guest exception vectors dynamically in unmapped memory */
360 	handler = gebase + 0x2000;
361 
362 	/* TLB refill (or XTLB refill on 64-bit VZ where KX=1) */
363 	refill_start = gebase;
364 	if (IS_ENABLED(CONFIG_KVM_MIPS_VZ) && IS_ENABLED(CONFIG_64BIT))
365 		refill_start += 0x080;
366 	refill_end = kvm_mips_build_tlb_refill_exception(refill_start, handler);
367 
368 	/* General Exception Entry point */
369 	kvm_mips_build_exception(gebase + 0x180, handler);
370 
371 	/* For vectored interrupts poke the exception code @ all offsets 0-7 */
372 	for (i = 0; i < 8; i++) {
373 		kvm_debug("L1 Vectored handler @ %p\n",
374 			  gebase + 0x200 + (i * VECTORSPACING));
375 		kvm_mips_build_exception(gebase + 0x200 + i * VECTORSPACING,
376 					 handler);
377 	}
378 
379 	/* General exit handler */
380 	p = handler;
381 	p = kvm_mips_build_exit(p);
382 
383 	/* Guest entry routine */
384 	vcpu->arch.vcpu_run = p;
385 	p = kvm_mips_build_vcpu_run(p);
386 
387 	/* Dump the generated code */
388 	pr_debug("#include <asm/asm.h>\n");
389 	pr_debug("#include <asm/regdef.h>\n");
390 	pr_debug("\n");
391 	dump_handler("kvm_vcpu_run", vcpu->arch.vcpu_run, p);
392 	dump_handler("kvm_tlb_refill", refill_start, refill_end);
393 	dump_handler("kvm_gen_exc", gebase + 0x180, gebase + 0x200);
394 	dump_handler("kvm_exit", gebase + 0x2000, vcpu->arch.vcpu_run);
395 
396 	/* Invalidate the icache for these ranges */
397 	flush_icache_range((unsigned long)gebase,
398 			   (unsigned long)gebase + ALIGN(size, PAGE_SIZE));
399 
400 	/*
401 	 * Allocate comm page for guest kernel, a TLB will be reserved for
402 	 * mapping GVA @ 0xFFFF8000 to this page
403 	 */
404 	vcpu->arch.kseg0_commpage = kzalloc(PAGE_SIZE << 1, GFP_KERNEL);
405 
406 	if (!vcpu->arch.kseg0_commpage) {
407 		err = -ENOMEM;
408 		goto out_free_gebase;
409 	}
410 
411 	kvm_debug("Allocated COMM page @ %p\n", vcpu->arch.kseg0_commpage);
412 	kvm_mips_commpage_init(vcpu);
413 
414 	/* Init */
415 	vcpu->arch.last_sched_cpu = -1;
416 	vcpu->arch.last_exec_cpu = -1;
417 
418 	/* Initial guest state */
419 	err = kvm_mips_callbacks->vcpu_setup(vcpu);
420 	if (err)
421 		goto out_free_commpage;
422 
423 	return 0;
424 
425 out_free_commpage:
426 	kfree(vcpu->arch.kseg0_commpage);
427 out_free_gebase:
428 	kfree(gebase);
429 out_uninit_vcpu:
430 	kvm_mips_callbacks->vcpu_uninit(vcpu);
431 	return err;
432 }
433 
434 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
435 {
436 	hrtimer_cancel(&vcpu->arch.comparecount_timer);
437 
438 	kvm_mips_dump_stats(vcpu);
439 
440 	kvm_mmu_free_memory_caches(vcpu);
441 	kfree(vcpu->arch.guest_ebase);
442 	kfree(vcpu->arch.kseg0_commpage);
443 
444 	kvm_mips_callbacks->vcpu_uninit(vcpu);
445 }
446 
447 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
448 					struct kvm_guest_debug *dbg)
449 {
450 	return -ENOIOCTLCMD;
451 }
452 
453 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
454 {
455 	int r = -EINTR;
456 
457 	vcpu_load(vcpu);
458 
459 	kvm_sigset_activate(vcpu);
460 
461 	if (vcpu->mmio_needed) {
462 		if (!vcpu->mmio_is_write)
463 			kvm_mips_complete_mmio_load(vcpu);
464 		vcpu->mmio_needed = 0;
465 	}
466 
467 	if (vcpu->run->immediate_exit)
468 		goto out;
469 
470 	lose_fpu(1);
471 
472 	local_irq_disable();
473 	guest_enter_irqoff();
474 	trace_kvm_enter(vcpu);
475 
476 	/*
477 	 * Make sure the read of VCPU requests in vcpu_run() callback is not
478 	 * reordered ahead of the write to vcpu->mode, or we could miss a TLB
479 	 * flush request while the requester sees the VCPU as outside of guest
480 	 * mode and not needing an IPI.
481 	 */
482 	smp_store_mb(vcpu->mode, IN_GUEST_MODE);
483 
484 	r = kvm_mips_callbacks->vcpu_run(vcpu);
485 
486 	trace_kvm_out(vcpu);
487 	guest_exit_irqoff();
488 	local_irq_enable();
489 
490 out:
491 	kvm_sigset_deactivate(vcpu);
492 
493 	vcpu_put(vcpu);
494 	return r;
495 }
496 
497 int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
498 			     struct kvm_mips_interrupt *irq)
499 {
500 	int intr = (int)irq->irq;
501 	struct kvm_vcpu *dvcpu = NULL;
502 
503 	if (intr == kvm_priority_to_irq[MIPS_EXC_INT_IPI_1] ||
504 	    intr == kvm_priority_to_irq[MIPS_EXC_INT_IPI_2] ||
505 	    intr == (-kvm_priority_to_irq[MIPS_EXC_INT_IPI_1]) ||
506 	    intr == (-kvm_priority_to_irq[MIPS_EXC_INT_IPI_2]))
507 		kvm_debug("%s: CPU: %d, INTR: %d\n", __func__, irq->cpu,
508 			  (int)intr);
509 
510 	if (irq->cpu == -1)
511 		dvcpu = vcpu;
512 	else
513 		dvcpu = vcpu->kvm->vcpus[irq->cpu];
514 
515 	if (intr == 2 || intr == 3 || intr == 4 || intr == 6) {
516 		kvm_mips_callbacks->queue_io_int(dvcpu, irq);
517 
518 	} else if (intr == -2 || intr == -3 || intr == -4 || intr == -6) {
519 		kvm_mips_callbacks->dequeue_io_int(dvcpu, irq);
520 	} else {
521 		kvm_err("%s: invalid interrupt ioctl (%d:%d)\n", __func__,
522 			irq->cpu, irq->irq);
523 		return -EINVAL;
524 	}
525 
526 	dvcpu->arch.wait = 0;
527 
528 	rcuwait_wake_up(&dvcpu->wait);
529 
530 	return 0;
531 }
532 
533 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
534 				    struct kvm_mp_state *mp_state)
535 {
536 	return -ENOIOCTLCMD;
537 }
538 
539 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
540 				    struct kvm_mp_state *mp_state)
541 {
542 	return -ENOIOCTLCMD;
543 }
544 
545 static u64 kvm_mips_get_one_regs[] = {
546 	KVM_REG_MIPS_R0,
547 	KVM_REG_MIPS_R1,
548 	KVM_REG_MIPS_R2,
549 	KVM_REG_MIPS_R3,
550 	KVM_REG_MIPS_R4,
551 	KVM_REG_MIPS_R5,
552 	KVM_REG_MIPS_R6,
553 	KVM_REG_MIPS_R7,
554 	KVM_REG_MIPS_R8,
555 	KVM_REG_MIPS_R9,
556 	KVM_REG_MIPS_R10,
557 	KVM_REG_MIPS_R11,
558 	KVM_REG_MIPS_R12,
559 	KVM_REG_MIPS_R13,
560 	KVM_REG_MIPS_R14,
561 	KVM_REG_MIPS_R15,
562 	KVM_REG_MIPS_R16,
563 	KVM_REG_MIPS_R17,
564 	KVM_REG_MIPS_R18,
565 	KVM_REG_MIPS_R19,
566 	KVM_REG_MIPS_R20,
567 	KVM_REG_MIPS_R21,
568 	KVM_REG_MIPS_R22,
569 	KVM_REG_MIPS_R23,
570 	KVM_REG_MIPS_R24,
571 	KVM_REG_MIPS_R25,
572 	KVM_REG_MIPS_R26,
573 	KVM_REG_MIPS_R27,
574 	KVM_REG_MIPS_R28,
575 	KVM_REG_MIPS_R29,
576 	KVM_REG_MIPS_R30,
577 	KVM_REG_MIPS_R31,
578 
579 #ifndef CONFIG_CPU_MIPSR6
580 	KVM_REG_MIPS_HI,
581 	KVM_REG_MIPS_LO,
582 #endif
583 	KVM_REG_MIPS_PC,
584 };
585 
586 static u64 kvm_mips_get_one_regs_fpu[] = {
587 	KVM_REG_MIPS_FCR_IR,
588 	KVM_REG_MIPS_FCR_CSR,
589 };
590 
591 static u64 kvm_mips_get_one_regs_msa[] = {
592 	KVM_REG_MIPS_MSA_IR,
593 	KVM_REG_MIPS_MSA_CSR,
594 };
595 
596 static unsigned long kvm_mips_num_regs(struct kvm_vcpu *vcpu)
597 {
598 	unsigned long ret;
599 
600 	ret = ARRAY_SIZE(kvm_mips_get_one_regs);
601 	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
602 		ret += ARRAY_SIZE(kvm_mips_get_one_regs_fpu) + 48;
603 		/* odd doubles */
604 		if (boot_cpu_data.fpu_id & MIPS_FPIR_F64)
605 			ret += 16;
606 	}
607 	if (kvm_mips_guest_can_have_msa(&vcpu->arch))
608 		ret += ARRAY_SIZE(kvm_mips_get_one_regs_msa) + 32;
609 	ret += kvm_mips_callbacks->num_regs(vcpu);
610 
611 	return ret;
612 }
613 
614 static int kvm_mips_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices)
615 {
616 	u64 index;
617 	unsigned int i;
618 
619 	if (copy_to_user(indices, kvm_mips_get_one_regs,
620 			 sizeof(kvm_mips_get_one_regs)))
621 		return -EFAULT;
622 	indices += ARRAY_SIZE(kvm_mips_get_one_regs);
623 
624 	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
625 		if (copy_to_user(indices, kvm_mips_get_one_regs_fpu,
626 				 sizeof(kvm_mips_get_one_regs_fpu)))
627 			return -EFAULT;
628 		indices += ARRAY_SIZE(kvm_mips_get_one_regs_fpu);
629 
630 		for (i = 0; i < 32; ++i) {
631 			index = KVM_REG_MIPS_FPR_32(i);
632 			if (copy_to_user(indices, &index, sizeof(index)))
633 				return -EFAULT;
634 			++indices;
635 
636 			/* skip odd doubles if no F64 */
637 			if (i & 1 && !(boot_cpu_data.fpu_id & MIPS_FPIR_F64))
638 				continue;
639 
640 			index = KVM_REG_MIPS_FPR_64(i);
641 			if (copy_to_user(indices, &index, sizeof(index)))
642 				return -EFAULT;
643 			++indices;
644 		}
645 	}
646 
647 	if (kvm_mips_guest_can_have_msa(&vcpu->arch)) {
648 		if (copy_to_user(indices, kvm_mips_get_one_regs_msa,
649 				 sizeof(kvm_mips_get_one_regs_msa)))
650 			return -EFAULT;
651 		indices += ARRAY_SIZE(kvm_mips_get_one_regs_msa);
652 
653 		for (i = 0; i < 32; ++i) {
654 			index = KVM_REG_MIPS_VEC_128(i);
655 			if (copy_to_user(indices, &index, sizeof(index)))
656 				return -EFAULT;
657 			++indices;
658 		}
659 	}
660 
661 	return kvm_mips_callbacks->copy_reg_indices(vcpu, indices);
662 }
663 
664 static int kvm_mips_get_reg(struct kvm_vcpu *vcpu,
665 			    const struct kvm_one_reg *reg)
666 {
667 	struct mips_coproc *cop0 = vcpu->arch.cop0;
668 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
669 	int ret;
670 	s64 v;
671 	s64 vs[2];
672 	unsigned int idx;
673 
674 	switch (reg->id) {
675 	/* General purpose registers */
676 	case KVM_REG_MIPS_R0 ... KVM_REG_MIPS_R31:
677 		v = (long)vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0];
678 		break;
679 #ifndef CONFIG_CPU_MIPSR6
680 	case KVM_REG_MIPS_HI:
681 		v = (long)vcpu->arch.hi;
682 		break;
683 	case KVM_REG_MIPS_LO:
684 		v = (long)vcpu->arch.lo;
685 		break;
686 #endif
687 	case KVM_REG_MIPS_PC:
688 		v = (long)vcpu->arch.pc;
689 		break;
690 
691 	/* Floating point registers */
692 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
693 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
694 			return -EINVAL;
695 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
696 		/* Odd singles in top of even double when FR=0 */
697 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
698 			v = get_fpr32(&fpu->fpr[idx], 0);
699 		else
700 			v = get_fpr32(&fpu->fpr[idx & ~1], idx & 1);
701 		break;
702 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
703 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
704 			return -EINVAL;
705 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
706 		/* Can't access odd doubles in FR=0 mode */
707 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
708 			return -EINVAL;
709 		v = get_fpr64(&fpu->fpr[idx], 0);
710 		break;
711 	case KVM_REG_MIPS_FCR_IR:
712 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
713 			return -EINVAL;
714 		v = boot_cpu_data.fpu_id;
715 		break;
716 	case KVM_REG_MIPS_FCR_CSR:
717 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
718 			return -EINVAL;
719 		v = fpu->fcr31;
720 		break;
721 
722 	/* MIPS SIMD Architecture (MSA) registers */
723 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
724 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
725 			return -EINVAL;
726 		/* Can't access MSA registers in FR=0 mode */
727 		if (!(kvm_read_c0_guest_status(cop0) & ST0_FR))
728 			return -EINVAL;
729 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
730 #ifdef CONFIG_CPU_LITTLE_ENDIAN
731 		/* least significant byte first */
732 		vs[0] = get_fpr64(&fpu->fpr[idx], 0);
733 		vs[1] = get_fpr64(&fpu->fpr[idx], 1);
734 #else
735 		/* most significant byte first */
736 		vs[0] = get_fpr64(&fpu->fpr[idx], 1);
737 		vs[1] = get_fpr64(&fpu->fpr[idx], 0);
738 #endif
739 		break;
740 	case KVM_REG_MIPS_MSA_IR:
741 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
742 			return -EINVAL;
743 		v = boot_cpu_data.msa_id;
744 		break;
745 	case KVM_REG_MIPS_MSA_CSR:
746 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
747 			return -EINVAL;
748 		v = fpu->msacsr;
749 		break;
750 
751 	/* registers to be handled specially */
752 	default:
753 		ret = kvm_mips_callbacks->get_one_reg(vcpu, reg, &v);
754 		if (ret)
755 			return ret;
756 		break;
757 	}
758 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
759 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
760 
761 		return put_user(v, uaddr64);
762 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
763 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
764 		u32 v32 = (u32)v;
765 
766 		return put_user(v32, uaddr32);
767 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
768 		void __user *uaddr = (void __user *)(long)reg->addr;
769 
770 		return copy_to_user(uaddr, vs, 16) ? -EFAULT : 0;
771 	} else {
772 		return -EINVAL;
773 	}
774 }
775 
776 static int kvm_mips_set_reg(struct kvm_vcpu *vcpu,
777 			    const struct kvm_one_reg *reg)
778 {
779 	struct mips_coproc *cop0 = vcpu->arch.cop0;
780 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
781 	s64 v;
782 	s64 vs[2];
783 	unsigned int idx;
784 
785 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
786 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
787 
788 		if (get_user(v, uaddr64) != 0)
789 			return -EFAULT;
790 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
791 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
792 		s32 v32;
793 
794 		if (get_user(v32, uaddr32) != 0)
795 			return -EFAULT;
796 		v = (s64)v32;
797 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
798 		void __user *uaddr = (void __user *)(long)reg->addr;
799 
800 		return copy_from_user(vs, uaddr, 16) ? -EFAULT : 0;
801 	} else {
802 		return -EINVAL;
803 	}
804 
805 	switch (reg->id) {
806 	/* General purpose registers */
807 	case KVM_REG_MIPS_R0:
808 		/* Silently ignore requests to set $0 */
809 		break;
810 	case KVM_REG_MIPS_R1 ... KVM_REG_MIPS_R31:
811 		vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0] = v;
812 		break;
813 #ifndef CONFIG_CPU_MIPSR6
814 	case KVM_REG_MIPS_HI:
815 		vcpu->arch.hi = v;
816 		break;
817 	case KVM_REG_MIPS_LO:
818 		vcpu->arch.lo = v;
819 		break;
820 #endif
821 	case KVM_REG_MIPS_PC:
822 		vcpu->arch.pc = v;
823 		break;
824 
825 	/* Floating point registers */
826 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
827 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
828 			return -EINVAL;
829 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
830 		/* Odd singles in top of even double when FR=0 */
831 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
832 			set_fpr32(&fpu->fpr[idx], 0, v);
833 		else
834 			set_fpr32(&fpu->fpr[idx & ~1], idx & 1, v);
835 		break;
836 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
837 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
838 			return -EINVAL;
839 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
840 		/* Can't access odd doubles in FR=0 mode */
841 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
842 			return -EINVAL;
843 		set_fpr64(&fpu->fpr[idx], 0, v);
844 		break;
845 	case KVM_REG_MIPS_FCR_IR:
846 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
847 			return -EINVAL;
848 		/* Read-only */
849 		break;
850 	case KVM_REG_MIPS_FCR_CSR:
851 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
852 			return -EINVAL;
853 		fpu->fcr31 = v;
854 		break;
855 
856 	/* MIPS SIMD Architecture (MSA) registers */
857 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
858 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
859 			return -EINVAL;
860 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
861 #ifdef CONFIG_CPU_LITTLE_ENDIAN
862 		/* least significant byte first */
863 		set_fpr64(&fpu->fpr[idx], 0, vs[0]);
864 		set_fpr64(&fpu->fpr[idx], 1, vs[1]);
865 #else
866 		/* most significant byte first */
867 		set_fpr64(&fpu->fpr[idx], 1, vs[0]);
868 		set_fpr64(&fpu->fpr[idx], 0, vs[1]);
869 #endif
870 		break;
871 	case KVM_REG_MIPS_MSA_IR:
872 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
873 			return -EINVAL;
874 		/* Read-only */
875 		break;
876 	case KVM_REG_MIPS_MSA_CSR:
877 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
878 			return -EINVAL;
879 		fpu->msacsr = v;
880 		break;
881 
882 	/* registers to be handled specially */
883 	default:
884 		return kvm_mips_callbacks->set_one_reg(vcpu, reg, v);
885 	}
886 	return 0;
887 }
888 
889 static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
890 				     struct kvm_enable_cap *cap)
891 {
892 	int r = 0;
893 
894 	if (!kvm_vm_ioctl_check_extension(vcpu->kvm, cap->cap))
895 		return -EINVAL;
896 	if (cap->flags)
897 		return -EINVAL;
898 	if (cap->args[0])
899 		return -EINVAL;
900 
901 	switch (cap->cap) {
902 	case KVM_CAP_MIPS_FPU:
903 		vcpu->arch.fpu_enabled = true;
904 		break;
905 	case KVM_CAP_MIPS_MSA:
906 		vcpu->arch.msa_enabled = true;
907 		break;
908 	default:
909 		r = -EINVAL;
910 		break;
911 	}
912 
913 	return r;
914 }
915 
916 long kvm_arch_vcpu_async_ioctl(struct file *filp, unsigned int ioctl,
917 			       unsigned long arg)
918 {
919 	struct kvm_vcpu *vcpu = filp->private_data;
920 	void __user *argp = (void __user *)arg;
921 
922 	if (ioctl == KVM_INTERRUPT) {
923 		struct kvm_mips_interrupt irq;
924 
925 		if (copy_from_user(&irq, argp, sizeof(irq)))
926 			return -EFAULT;
927 		kvm_debug("[%d] %s: irq: %d\n", vcpu->vcpu_id, __func__,
928 			  irq.irq);
929 
930 		return kvm_vcpu_ioctl_interrupt(vcpu, &irq);
931 	}
932 
933 	return -ENOIOCTLCMD;
934 }
935 
936 long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl,
937 			 unsigned long arg)
938 {
939 	struct kvm_vcpu *vcpu = filp->private_data;
940 	void __user *argp = (void __user *)arg;
941 	long r;
942 
943 	vcpu_load(vcpu);
944 
945 	switch (ioctl) {
946 	case KVM_SET_ONE_REG:
947 	case KVM_GET_ONE_REG: {
948 		struct kvm_one_reg reg;
949 
950 		r = -EFAULT;
951 		if (copy_from_user(&reg, argp, sizeof(reg)))
952 			break;
953 		if (ioctl == KVM_SET_ONE_REG)
954 			r = kvm_mips_set_reg(vcpu, &reg);
955 		else
956 			r = kvm_mips_get_reg(vcpu, &reg);
957 		break;
958 	}
959 	case KVM_GET_REG_LIST: {
960 		struct kvm_reg_list __user *user_list = argp;
961 		struct kvm_reg_list reg_list;
962 		unsigned n;
963 
964 		r = -EFAULT;
965 		if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
966 			break;
967 		n = reg_list.n;
968 		reg_list.n = kvm_mips_num_regs(vcpu);
969 		if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
970 			break;
971 		r = -E2BIG;
972 		if (n < reg_list.n)
973 			break;
974 		r = kvm_mips_copy_reg_indices(vcpu, user_list->reg);
975 		break;
976 	}
977 	case KVM_ENABLE_CAP: {
978 		struct kvm_enable_cap cap;
979 
980 		r = -EFAULT;
981 		if (copy_from_user(&cap, argp, sizeof(cap)))
982 			break;
983 		r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
984 		break;
985 	}
986 	default:
987 		r = -ENOIOCTLCMD;
988 	}
989 
990 	vcpu_put(vcpu);
991 	return r;
992 }
993 
994 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
995 {
996 
997 }
998 
999 void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
1000 					struct kvm_memory_slot *memslot)
1001 {
1002 	/* Let implementation handle TLB/GVA invalidation */
1003 	kvm_mips_callbacks->flush_shadow_memslot(kvm, memslot);
1004 }
1005 
1006 long kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
1007 {
1008 	long r;
1009 
1010 	switch (ioctl) {
1011 	default:
1012 		r = -ENOIOCTLCMD;
1013 	}
1014 
1015 	return r;
1016 }
1017 
1018 int kvm_arch_init(void *opaque)
1019 {
1020 	if (kvm_mips_callbacks) {
1021 		kvm_err("kvm: module already exists\n");
1022 		return -EEXIST;
1023 	}
1024 
1025 	return kvm_mips_emulation_init(&kvm_mips_callbacks);
1026 }
1027 
1028 void kvm_arch_exit(void)
1029 {
1030 	kvm_mips_callbacks = NULL;
1031 }
1032 
1033 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
1034 				  struct kvm_sregs *sregs)
1035 {
1036 	return -ENOIOCTLCMD;
1037 }
1038 
1039 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
1040 				  struct kvm_sregs *sregs)
1041 {
1042 	return -ENOIOCTLCMD;
1043 }
1044 
1045 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
1046 {
1047 }
1048 
1049 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1050 {
1051 	return -ENOIOCTLCMD;
1052 }
1053 
1054 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1055 {
1056 	return -ENOIOCTLCMD;
1057 }
1058 
1059 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
1060 {
1061 	return VM_FAULT_SIGBUS;
1062 }
1063 
1064 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
1065 {
1066 	int r;
1067 
1068 	switch (ext) {
1069 	case KVM_CAP_ONE_REG:
1070 	case KVM_CAP_ENABLE_CAP:
1071 	case KVM_CAP_READONLY_MEM:
1072 	case KVM_CAP_SYNC_MMU:
1073 	case KVM_CAP_IMMEDIATE_EXIT:
1074 		r = 1;
1075 		break;
1076 	case KVM_CAP_NR_VCPUS:
1077 		r = num_online_cpus();
1078 		break;
1079 	case KVM_CAP_MAX_VCPUS:
1080 		r = KVM_MAX_VCPUS;
1081 		break;
1082 	case KVM_CAP_MAX_VCPU_ID:
1083 		r = KVM_MAX_VCPU_ID;
1084 		break;
1085 	case KVM_CAP_MIPS_FPU:
1086 		/* We don't handle systems with inconsistent cpu_has_fpu */
1087 		r = !!raw_cpu_has_fpu;
1088 		break;
1089 	case KVM_CAP_MIPS_MSA:
1090 		/*
1091 		 * We don't support MSA vector partitioning yet:
1092 		 * 1) It would require explicit support which can't be tested
1093 		 *    yet due to lack of support in current hardware.
1094 		 * 2) It extends the state that would need to be saved/restored
1095 		 *    by e.g. QEMU for migration.
1096 		 *
1097 		 * When vector partitioning hardware becomes available, support
1098 		 * could be added by requiring a flag when enabling
1099 		 * KVM_CAP_MIPS_MSA capability to indicate that userland knows
1100 		 * to save/restore the appropriate extra state.
1101 		 */
1102 		r = cpu_has_msa && !(boot_cpu_data.msa_id & MSA_IR_WRPF);
1103 		break;
1104 	default:
1105 		r = kvm_mips_callbacks->check_extension(kvm, ext);
1106 		break;
1107 	}
1108 	return r;
1109 }
1110 
1111 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
1112 {
1113 	return kvm_mips_pending_timer(vcpu) ||
1114 		kvm_read_c0_guest_cause(vcpu->arch.cop0) & C_TI;
1115 }
1116 
1117 int kvm_arch_vcpu_dump_regs(struct kvm_vcpu *vcpu)
1118 {
1119 	int i;
1120 	struct mips_coproc *cop0;
1121 
1122 	if (!vcpu)
1123 		return -1;
1124 
1125 	kvm_debug("VCPU Register Dump:\n");
1126 	kvm_debug("\tpc = 0x%08lx\n", vcpu->arch.pc);
1127 	kvm_debug("\texceptions: %08lx\n", vcpu->arch.pending_exceptions);
1128 
1129 	for (i = 0; i < 32; i += 4) {
1130 		kvm_debug("\tgpr%02d: %08lx %08lx %08lx %08lx\n", i,
1131 		       vcpu->arch.gprs[i],
1132 		       vcpu->arch.gprs[i + 1],
1133 		       vcpu->arch.gprs[i + 2], vcpu->arch.gprs[i + 3]);
1134 	}
1135 	kvm_debug("\thi: 0x%08lx\n", vcpu->arch.hi);
1136 	kvm_debug("\tlo: 0x%08lx\n", vcpu->arch.lo);
1137 
1138 	cop0 = vcpu->arch.cop0;
1139 	kvm_debug("\tStatus: 0x%08x, Cause: 0x%08x\n",
1140 		  kvm_read_c0_guest_status(cop0),
1141 		  kvm_read_c0_guest_cause(cop0));
1142 
1143 	kvm_debug("\tEPC: 0x%08lx\n", kvm_read_c0_guest_epc(cop0));
1144 
1145 	return 0;
1146 }
1147 
1148 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1149 {
1150 	int i;
1151 
1152 	vcpu_load(vcpu);
1153 
1154 	for (i = 1; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1155 		vcpu->arch.gprs[i] = regs->gpr[i];
1156 	vcpu->arch.gprs[0] = 0; /* zero is special, and cannot be set. */
1157 	vcpu->arch.hi = regs->hi;
1158 	vcpu->arch.lo = regs->lo;
1159 	vcpu->arch.pc = regs->pc;
1160 
1161 	vcpu_put(vcpu);
1162 	return 0;
1163 }
1164 
1165 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1166 {
1167 	int i;
1168 
1169 	vcpu_load(vcpu);
1170 
1171 	for (i = 0; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1172 		regs->gpr[i] = vcpu->arch.gprs[i];
1173 
1174 	regs->hi = vcpu->arch.hi;
1175 	regs->lo = vcpu->arch.lo;
1176 	regs->pc = vcpu->arch.pc;
1177 
1178 	vcpu_put(vcpu);
1179 	return 0;
1180 }
1181 
1182 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
1183 				  struct kvm_translation *tr)
1184 {
1185 	return 0;
1186 }
1187 
1188 static void kvm_mips_set_c0_status(void)
1189 {
1190 	u32 status = read_c0_status();
1191 
1192 	if (cpu_has_dsp)
1193 		status |= (ST0_MX);
1194 
1195 	write_c0_status(status);
1196 	ehb();
1197 }
1198 
1199 /*
1200  * Return value is in the form (errcode<<2 | RESUME_FLAG_HOST | RESUME_FLAG_NV)
1201  */
1202 int kvm_mips_handle_exit(struct kvm_vcpu *vcpu)
1203 {
1204 	struct kvm_run *run = vcpu->run;
1205 	u32 cause = vcpu->arch.host_cp0_cause;
1206 	u32 exccode = (cause >> CAUSEB_EXCCODE) & 0x1f;
1207 	u32 __user *opc = (u32 __user *) vcpu->arch.pc;
1208 	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
1209 	enum emulation_result er = EMULATE_DONE;
1210 	u32 inst;
1211 	int ret = RESUME_GUEST;
1212 
1213 	vcpu->mode = OUTSIDE_GUEST_MODE;
1214 
1215 	/* re-enable HTW before enabling interrupts */
1216 	if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ))
1217 		htw_start();
1218 
1219 	/* Set a default exit reason */
1220 	run->exit_reason = KVM_EXIT_UNKNOWN;
1221 	run->ready_for_interrupt_injection = 1;
1222 
1223 	/*
1224 	 * Set the appropriate status bits based on host CPU features,
1225 	 * before we hit the scheduler
1226 	 */
1227 	kvm_mips_set_c0_status();
1228 
1229 	local_irq_enable();
1230 
1231 	kvm_debug("kvm_mips_handle_exit: cause: %#x, PC: %p, kvm_run: %p, kvm_vcpu: %p\n",
1232 			cause, opc, run, vcpu);
1233 	trace_kvm_exit(vcpu, exccode);
1234 
1235 	if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) {
1236 		/*
1237 		 * Do a privilege check, if in UM most of these exit conditions
1238 		 * end up causing an exception to be delivered to the Guest
1239 		 * Kernel
1240 		 */
1241 		er = kvm_mips_check_privilege(cause, opc, vcpu);
1242 		if (er == EMULATE_PRIV_FAIL) {
1243 			goto skip_emul;
1244 		} else if (er == EMULATE_FAIL) {
1245 			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1246 			ret = RESUME_HOST;
1247 			goto skip_emul;
1248 		}
1249 	}
1250 
1251 	switch (exccode) {
1252 	case EXCCODE_INT:
1253 		kvm_debug("[%d]EXCCODE_INT @ %p\n", vcpu->vcpu_id, opc);
1254 
1255 		++vcpu->stat.int_exits;
1256 
1257 		if (need_resched())
1258 			cond_resched();
1259 
1260 		ret = RESUME_GUEST;
1261 		break;
1262 
1263 	case EXCCODE_CPU:
1264 		kvm_debug("EXCCODE_CPU: @ PC: %p\n", opc);
1265 
1266 		++vcpu->stat.cop_unusable_exits;
1267 		ret = kvm_mips_callbacks->handle_cop_unusable(vcpu);
1268 		/* XXXKYMA: Might need to return to user space */
1269 		if (run->exit_reason == KVM_EXIT_IRQ_WINDOW_OPEN)
1270 			ret = RESUME_HOST;
1271 		break;
1272 
1273 	case EXCCODE_MOD:
1274 		++vcpu->stat.tlbmod_exits;
1275 		ret = kvm_mips_callbacks->handle_tlb_mod(vcpu);
1276 		break;
1277 
1278 	case EXCCODE_TLBS:
1279 		kvm_debug("TLB ST fault:  cause %#x, status %#x, PC: %p, BadVaddr: %#lx\n",
1280 			  cause, kvm_read_c0_guest_status(vcpu->arch.cop0), opc,
1281 			  badvaddr);
1282 
1283 		++vcpu->stat.tlbmiss_st_exits;
1284 		ret = kvm_mips_callbacks->handle_tlb_st_miss(vcpu);
1285 		break;
1286 
1287 	case EXCCODE_TLBL:
1288 		kvm_debug("TLB LD fault: cause %#x, PC: %p, BadVaddr: %#lx\n",
1289 			  cause, opc, badvaddr);
1290 
1291 		++vcpu->stat.tlbmiss_ld_exits;
1292 		ret = kvm_mips_callbacks->handle_tlb_ld_miss(vcpu);
1293 		break;
1294 
1295 	case EXCCODE_ADES:
1296 		++vcpu->stat.addrerr_st_exits;
1297 		ret = kvm_mips_callbacks->handle_addr_err_st(vcpu);
1298 		break;
1299 
1300 	case EXCCODE_ADEL:
1301 		++vcpu->stat.addrerr_ld_exits;
1302 		ret = kvm_mips_callbacks->handle_addr_err_ld(vcpu);
1303 		break;
1304 
1305 	case EXCCODE_SYS:
1306 		++vcpu->stat.syscall_exits;
1307 		ret = kvm_mips_callbacks->handle_syscall(vcpu);
1308 		break;
1309 
1310 	case EXCCODE_RI:
1311 		++vcpu->stat.resvd_inst_exits;
1312 		ret = kvm_mips_callbacks->handle_res_inst(vcpu);
1313 		break;
1314 
1315 	case EXCCODE_BP:
1316 		++vcpu->stat.break_inst_exits;
1317 		ret = kvm_mips_callbacks->handle_break(vcpu);
1318 		break;
1319 
1320 	case EXCCODE_TR:
1321 		++vcpu->stat.trap_inst_exits;
1322 		ret = kvm_mips_callbacks->handle_trap(vcpu);
1323 		break;
1324 
1325 	case EXCCODE_MSAFPE:
1326 		++vcpu->stat.msa_fpe_exits;
1327 		ret = kvm_mips_callbacks->handle_msa_fpe(vcpu);
1328 		break;
1329 
1330 	case EXCCODE_FPE:
1331 		++vcpu->stat.fpe_exits;
1332 		ret = kvm_mips_callbacks->handle_fpe(vcpu);
1333 		break;
1334 
1335 	case EXCCODE_MSADIS:
1336 		++vcpu->stat.msa_disabled_exits;
1337 		ret = kvm_mips_callbacks->handle_msa_disabled(vcpu);
1338 		break;
1339 
1340 	case EXCCODE_GE:
1341 		/* defer exit accounting to handler */
1342 		ret = kvm_mips_callbacks->handle_guest_exit(vcpu);
1343 		break;
1344 
1345 	default:
1346 		if (cause & CAUSEF_BD)
1347 			opc += 1;
1348 		inst = 0;
1349 		kvm_get_badinstr(opc, vcpu, &inst);
1350 		kvm_err("Exception Code: %d, not yet handled, @ PC: %p, inst: 0x%08x  BadVaddr: %#lx Status: %#x\n",
1351 			exccode, opc, inst, badvaddr,
1352 			kvm_read_c0_guest_status(vcpu->arch.cop0));
1353 		kvm_arch_vcpu_dump_regs(vcpu);
1354 		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1355 		ret = RESUME_HOST;
1356 		break;
1357 
1358 	}
1359 
1360 skip_emul:
1361 	local_irq_disable();
1362 
1363 	if (ret == RESUME_GUEST)
1364 		kvm_vz_acquire_htimer(vcpu);
1365 
1366 	if (er == EMULATE_DONE && !(ret & RESUME_HOST))
1367 		kvm_mips_deliver_interrupts(vcpu, cause);
1368 
1369 	if (!(ret & RESUME_HOST)) {
1370 		/* Only check for signals if not already exiting to userspace */
1371 		if (signal_pending(current)) {
1372 			run->exit_reason = KVM_EXIT_INTR;
1373 			ret = (-EINTR << 2) | RESUME_HOST;
1374 			++vcpu->stat.signal_exits;
1375 			trace_kvm_exit(vcpu, KVM_TRACE_EXIT_SIGNAL);
1376 		}
1377 	}
1378 
1379 	if (ret == RESUME_GUEST) {
1380 		trace_kvm_reenter(vcpu);
1381 
1382 		/*
1383 		 * Make sure the read of VCPU requests in vcpu_reenter()
1384 		 * callback is not reordered ahead of the write to vcpu->mode,
1385 		 * or we could miss a TLB flush request while the requester sees
1386 		 * the VCPU as outside of guest mode and not needing an IPI.
1387 		 */
1388 		smp_store_mb(vcpu->mode, IN_GUEST_MODE);
1389 
1390 		kvm_mips_callbacks->vcpu_reenter(vcpu);
1391 
1392 		/*
1393 		 * If FPU / MSA are enabled (i.e. the guest's FPU / MSA context
1394 		 * is live), restore FCR31 / MSACSR.
1395 		 *
1396 		 * This should be before returning to the guest exception
1397 		 * vector, as it may well cause an [MSA] FP exception if there
1398 		 * are pending exception bits unmasked. (see
1399 		 * kvm_mips_csr_die_notifier() for how that is handled).
1400 		 */
1401 		if (kvm_mips_guest_has_fpu(&vcpu->arch) &&
1402 		    read_c0_status() & ST0_CU1)
1403 			__kvm_restore_fcsr(&vcpu->arch);
1404 
1405 		if (kvm_mips_guest_has_msa(&vcpu->arch) &&
1406 		    read_c0_config5() & MIPS_CONF5_MSAEN)
1407 			__kvm_restore_msacsr(&vcpu->arch);
1408 	}
1409 
1410 	/* Disable HTW before returning to guest or host */
1411 	if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ))
1412 		htw_stop();
1413 
1414 	return ret;
1415 }
1416 
1417 /* Enable FPU for guest and restore context */
1418 void kvm_own_fpu(struct kvm_vcpu *vcpu)
1419 {
1420 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1421 	unsigned int sr, cfg5;
1422 
1423 	preempt_disable();
1424 
1425 	sr = kvm_read_c0_guest_status(cop0);
1426 
1427 	/*
1428 	 * If MSA state is already live, it is undefined how it interacts with
1429 	 * FR=0 FPU state, and we don't want to hit reserved instruction
1430 	 * exceptions trying to save the MSA state later when CU=1 && FR=1, so
1431 	 * play it safe and save it first.
1432 	 *
1433 	 * In theory we shouldn't ever hit this case since kvm_lose_fpu() should
1434 	 * get called when guest CU1 is set, however we can't trust the guest
1435 	 * not to clobber the status register directly via the commpage.
1436 	 */
1437 	if (cpu_has_msa && sr & ST0_CU1 && !(sr & ST0_FR) &&
1438 	    vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA)
1439 		kvm_lose_fpu(vcpu);
1440 
1441 	/*
1442 	 * Enable FPU for guest
1443 	 * We set FR and FRE according to guest context
1444 	 */
1445 	change_c0_status(ST0_CU1 | ST0_FR, sr);
1446 	if (cpu_has_fre) {
1447 		cfg5 = kvm_read_c0_guest_config5(cop0);
1448 		change_c0_config5(MIPS_CONF5_FRE, cfg5);
1449 	}
1450 	enable_fpu_hazard();
1451 
1452 	/* If guest FPU state not active, restore it now */
1453 	if (!(vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU)) {
1454 		__kvm_restore_fpu(&vcpu->arch);
1455 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1456 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_FPU);
1457 	} else {
1458 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_FPU);
1459 	}
1460 
1461 	preempt_enable();
1462 }
1463 
1464 #ifdef CONFIG_CPU_HAS_MSA
1465 /* Enable MSA for guest and restore context */
1466 void kvm_own_msa(struct kvm_vcpu *vcpu)
1467 {
1468 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1469 	unsigned int sr, cfg5;
1470 
1471 	preempt_disable();
1472 
1473 	/*
1474 	 * Enable FPU if enabled in guest, since we're restoring FPU context
1475 	 * anyway. We set FR and FRE according to guest context.
1476 	 */
1477 	if (kvm_mips_guest_has_fpu(&vcpu->arch)) {
1478 		sr = kvm_read_c0_guest_status(cop0);
1479 
1480 		/*
1481 		 * If FR=0 FPU state is already live, it is undefined how it
1482 		 * interacts with MSA state, so play it safe and save it first.
1483 		 */
1484 		if (!(sr & ST0_FR) &&
1485 		    (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU |
1486 				KVM_MIPS_AUX_MSA)) == KVM_MIPS_AUX_FPU)
1487 			kvm_lose_fpu(vcpu);
1488 
1489 		change_c0_status(ST0_CU1 | ST0_FR, sr);
1490 		if (sr & ST0_CU1 && cpu_has_fre) {
1491 			cfg5 = kvm_read_c0_guest_config5(cop0);
1492 			change_c0_config5(MIPS_CONF5_FRE, cfg5);
1493 		}
1494 	}
1495 
1496 	/* Enable MSA for guest */
1497 	set_c0_config5(MIPS_CONF5_MSAEN);
1498 	enable_fpu_hazard();
1499 
1500 	switch (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA)) {
1501 	case KVM_MIPS_AUX_FPU:
1502 		/*
1503 		 * Guest FPU state already loaded, only restore upper MSA state
1504 		 */
1505 		__kvm_restore_msa_upper(&vcpu->arch);
1506 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1507 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_MSA);
1508 		break;
1509 	case 0:
1510 		/* Neither FPU or MSA already active, restore full MSA state */
1511 		__kvm_restore_msa(&vcpu->arch);
1512 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1513 		if (kvm_mips_guest_has_fpu(&vcpu->arch))
1514 			vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1515 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE,
1516 			      KVM_TRACE_AUX_FPU_MSA);
1517 		break;
1518 	default:
1519 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_MSA);
1520 		break;
1521 	}
1522 
1523 	preempt_enable();
1524 }
1525 #endif
1526 
1527 /* Drop FPU & MSA without saving it */
1528 void kvm_drop_fpu(struct kvm_vcpu *vcpu)
1529 {
1530 	preempt_disable();
1531 	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1532 		disable_msa();
1533 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_MSA);
1534 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_MSA;
1535 	}
1536 	if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1537 		clear_c0_status(ST0_CU1 | ST0_FR);
1538 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_FPU);
1539 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1540 	}
1541 	preempt_enable();
1542 }
1543 
1544 /* Save and disable FPU & MSA */
1545 void kvm_lose_fpu(struct kvm_vcpu *vcpu)
1546 {
1547 	/*
1548 	 * With T&E, FPU & MSA get disabled in root context (hardware) when it
1549 	 * is disabled in guest context (software), but the register state in
1550 	 * the hardware may still be in use.
1551 	 * This is why we explicitly re-enable the hardware before saving.
1552 	 */
1553 
1554 	preempt_disable();
1555 	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1556 		if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) {
1557 			set_c0_config5(MIPS_CONF5_MSAEN);
1558 			enable_fpu_hazard();
1559 		}
1560 
1561 		__kvm_save_msa(&vcpu->arch);
1562 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU_MSA);
1563 
1564 		/* Disable MSA & FPU */
1565 		disable_msa();
1566 		if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1567 			clear_c0_status(ST0_CU1 | ST0_FR);
1568 			disable_fpu_hazard();
1569 		}
1570 		vcpu->arch.aux_inuse &= ~(KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA);
1571 	} else if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1572 		if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) {
1573 			set_c0_status(ST0_CU1);
1574 			enable_fpu_hazard();
1575 		}
1576 
1577 		__kvm_save_fpu(&vcpu->arch);
1578 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1579 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU);
1580 
1581 		/* Disable FPU */
1582 		clear_c0_status(ST0_CU1 | ST0_FR);
1583 		disable_fpu_hazard();
1584 	}
1585 	preempt_enable();
1586 }
1587 
1588 /*
1589  * Step over a specific ctc1 to FCSR and a specific ctcmsa to MSACSR which are
1590  * used to restore guest FCSR/MSACSR state and may trigger a "harmless" FP/MSAFP
1591  * exception if cause bits are set in the value being written.
1592  */
1593 static int kvm_mips_csr_die_notify(struct notifier_block *self,
1594 				   unsigned long cmd, void *ptr)
1595 {
1596 	struct die_args *args = (struct die_args *)ptr;
1597 	struct pt_regs *regs = args->regs;
1598 	unsigned long pc;
1599 
1600 	/* Only interested in FPE and MSAFPE */
1601 	if (cmd != DIE_FP && cmd != DIE_MSAFP)
1602 		return NOTIFY_DONE;
1603 
1604 	/* Return immediately if guest context isn't active */
1605 	if (!(current->flags & PF_VCPU))
1606 		return NOTIFY_DONE;
1607 
1608 	/* Should never get here from user mode */
1609 	BUG_ON(user_mode(regs));
1610 
1611 	pc = instruction_pointer(regs);
1612 	switch (cmd) {
1613 	case DIE_FP:
1614 		/* match 2nd instruction in __kvm_restore_fcsr */
1615 		if (pc != (unsigned long)&__kvm_restore_fcsr + 4)
1616 			return NOTIFY_DONE;
1617 		break;
1618 	case DIE_MSAFP:
1619 		/* match 2nd/3rd instruction in __kvm_restore_msacsr */
1620 		if (!cpu_has_msa ||
1621 		    pc < (unsigned long)&__kvm_restore_msacsr + 4 ||
1622 		    pc > (unsigned long)&__kvm_restore_msacsr + 8)
1623 			return NOTIFY_DONE;
1624 		break;
1625 	}
1626 
1627 	/* Move PC forward a little and continue executing */
1628 	instruction_pointer(regs) += 4;
1629 
1630 	return NOTIFY_STOP;
1631 }
1632 
1633 static struct notifier_block kvm_mips_csr_die_notifier = {
1634 	.notifier_call = kvm_mips_csr_die_notify,
1635 };
1636 
1637 static u32 kvm_default_priority_to_irq[MIPS_EXC_MAX] = {
1638 	[MIPS_EXC_INT_TIMER] = C_IRQ5,
1639 	[MIPS_EXC_INT_IO_1]  = C_IRQ0,
1640 	[MIPS_EXC_INT_IPI_1] = C_IRQ1,
1641 	[MIPS_EXC_INT_IPI_2] = C_IRQ2,
1642 };
1643 
1644 static u32 kvm_loongson3_priority_to_irq[MIPS_EXC_MAX] = {
1645 	[MIPS_EXC_INT_TIMER] = C_IRQ5,
1646 	[MIPS_EXC_INT_IO_1]  = C_IRQ0,
1647 	[MIPS_EXC_INT_IO_2]  = C_IRQ1,
1648 	[MIPS_EXC_INT_IPI_1] = C_IRQ4,
1649 };
1650 
1651 u32 *kvm_priority_to_irq = kvm_default_priority_to_irq;
1652 
1653 u32 kvm_irq_to_priority(u32 irq)
1654 {
1655 	int i;
1656 
1657 	for (i = MIPS_EXC_INT_TIMER; i < MIPS_EXC_MAX; i++) {
1658 		if (kvm_priority_to_irq[i] == (1 << (irq + 8)))
1659 			return i;
1660 	}
1661 
1662 	return MIPS_EXC_MAX;
1663 }
1664 
1665 static int __init kvm_mips_init(void)
1666 {
1667 	int ret;
1668 
1669 	if (cpu_has_mmid) {
1670 		pr_warn("KVM does not yet support MMIDs. KVM Disabled\n");
1671 		return -EOPNOTSUPP;
1672 	}
1673 
1674 	ret = kvm_mips_entry_setup();
1675 	if (ret)
1676 		return ret;
1677 
1678 	ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
1679 
1680 	if (ret)
1681 		return ret;
1682 
1683 	if (boot_cpu_type() == CPU_LOONGSON64)
1684 		kvm_priority_to_irq = kvm_loongson3_priority_to_irq;
1685 
1686 	register_die_notifier(&kvm_mips_csr_die_notifier);
1687 
1688 	return 0;
1689 }
1690 
1691 static void __exit kvm_mips_exit(void)
1692 {
1693 	kvm_exit();
1694 
1695 	unregister_die_notifier(&kvm_mips_csr_die_notifier);
1696 }
1697 
1698 module_init(kvm_mips_init);
1699 module_exit(kvm_mips_exit);
1700 
1701 EXPORT_TRACEPOINT_SYMBOL(kvm_exit);
1702