xref: /openbmc/linux/arch/mips/kvm/mips.c (revision 74be2d3b)
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 	VCPU_STAT("vz_cpucfg", vz_cpucfg_exits),
71 #endif
72 	VCPU_STAT("halt_successful_poll", halt_successful_poll),
73 	VCPU_STAT("halt_attempted_poll", halt_attempted_poll),
74 	VCPU_STAT("halt_poll_invalid", halt_poll_invalid),
75 	VCPU_STAT("halt_wakeup", halt_wakeup),
76 	VCPU_STAT("halt_poll_success_ns", halt_poll_success_ns),
77 	VCPU_STAT("halt_poll_fail_ns", halt_poll_fail_ns),
78 	{NULL}
79 };
80 
81 bool kvm_trace_guest_mode_change;
82 
83 int kvm_guest_mode_change_trace_reg(void)
84 {
85 	kvm_trace_guest_mode_change = true;
86 	return 0;
87 }
88 
89 void kvm_guest_mode_change_trace_unreg(void)
90 {
91 	kvm_trace_guest_mode_change = false;
92 }
93 
94 /*
95  * XXXKYMA: We are simulatoring a processor that has the WII bit set in
96  * Config7, so we are "runnable" if interrupts are pending
97  */
98 int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
99 {
100 	return !!(vcpu->arch.pending_exceptions);
101 }
102 
103 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
104 {
105 	return false;
106 }
107 
108 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
109 {
110 	return 1;
111 }
112 
113 int kvm_arch_hardware_enable(void)
114 {
115 	return kvm_mips_callbacks->hardware_enable();
116 }
117 
118 void kvm_arch_hardware_disable(void)
119 {
120 	kvm_mips_callbacks->hardware_disable();
121 }
122 
123 int kvm_arch_hardware_setup(void *opaque)
124 {
125 	return 0;
126 }
127 
128 int kvm_arch_check_processor_compat(void *opaque)
129 {
130 	return 0;
131 }
132 
133 extern void kvm_init_loongson_ipi(struct kvm *kvm);
134 
135 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
136 {
137 	switch (type) {
138 #ifdef CONFIG_KVM_MIPS_VZ
139 	case KVM_VM_MIPS_VZ:
140 #else
141 	case KVM_VM_MIPS_TE:
142 #endif
143 		break;
144 	default:
145 		/* Unsupported KVM type */
146 		return -EINVAL;
147 	};
148 
149 	/* Allocate page table to map GPA -> RPA */
150 	kvm->arch.gpa_mm.pgd = kvm_pgd_alloc();
151 	if (!kvm->arch.gpa_mm.pgd)
152 		return -ENOMEM;
153 
154 #ifdef CONFIG_CPU_LOONGSON64
155 	kvm_init_loongson_ipi(kvm);
156 #endif
157 
158 	return 0;
159 }
160 
161 void kvm_mips_free_vcpus(struct kvm *kvm)
162 {
163 	unsigned int i;
164 	struct kvm_vcpu *vcpu;
165 
166 	kvm_for_each_vcpu(i, vcpu, kvm) {
167 		kvm_vcpu_destroy(vcpu);
168 	}
169 
170 	mutex_lock(&kvm->lock);
171 
172 	for (i = 0; i < atomic_read(&kvm->online_vcpus); i++)
173 		kvm->vcpus[i] = NULL;
174 
175 	atomic_set(&kvm->online_vcpus, 0);
176 
177 	mutex_unlock(&kvm->lock);
178 }
179 
180 static void kvm_mips_free_gpa_pt(struct kvm *kvm)
181 {
182 	/* It should always be safe to remove after flushing the whole range */
183 	WARN_ON(!kvm_mips_flush_gpa_pt(kvm, 0, ~0));
184 	pgd_free(NULL, kvm->arch.gpa_mm.pgd);
185 }
186 
187 void kvm_arch_destroy_vm(struct kvm *kvm)
188 {
189 	kvm_mips_free_vcpus(kvm);
190 	kvm_mips_free_gpa_pt(kvm);
191 }
192 
193 long kvm_arch_dev_ioctl(struct file *filp, unsigned int ioctl,
194 			unsigned long arg)
195 {
196 	return -ENOIOCTLCMD;
197 }
198 
199 void kvm_arch_flush_shadow_all(struct kvm *kvm)
200 {
201 	/* Flush whole GPA */
202 	kvm_mips_flush_gpa_pt(kvm, 0, ~0);
203 
204 	/* Let implementation do the rest */
205 	kvm_mips_callbacks->flush_shadow_all(kvm);
206 }
207 
208 void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
209 				   struct kvm_memory_slot *slot)
210 {
211 	/*
212 	 * The slot has been made invalid (ready for moving or deletion), so we
213 	 * need to ensure that it can no longer be accessed by any guest VCPUs.
214 	 */
215 
216 	spin_lock(&kvm->mmu_lock);
217 	/* Flush slot from GPA */
218 	kvm_mips_flush_gpa_pt(kvm, slot->base_gfn,
219 			      slot->base_gfn + slot->npages - 1);
220 	/* Let implementation do the rest */
221 	kvm_mips_callbacks->flush_shadow_memslot(kvm, slot);
222 	spin_unlock(&kvm->mmu_lock);
223 }
224 
225 int kvm_arch_prepare_memory_region(struct kvm *kvm,
226 				   struct kvm_memory_slot *memslot,
227 				   const struct kvm_userspace_memory_region *mem,
228 				   enum kvm_mr_change change)
229 {
230 	return 0;
231 }
232 
233 void kvm_arch_commit_memory_region(struct kvm *kvm,
234 				   const struct kvm_userspace_memory_region *mem,
235 				   struct kvm_memory_slot *old,
236 				   const struct kvm_memory_slot *new,
237 				   enum kvm_mr_change change)
238 {
239 	int needs_flush;
240 
241 	kvm_debug("%s: kvm: %p slot: %d, GPA: %llx, size: %llx, QVA: %llx\n",
242 		  __func__, kvm, mem->slot, mem->guest_phys_addr,
243 		  mem->memory_size, mem->userspace_addr);
244 
245 	/*
246 	 * If dirty page logging is enabled, write protect all pages in the slot
247 	 * ready for dirty logging.
248 	 *
249 	 * There is no need to do this in any of the following cases:
250 	 * CREATE:	No dirty mappings will already exist.
251 	 * MOVE/DELETE:	The old mappings will already have been cleaned up by
252 	 *		kvm_arch_flush_shadow_memslot()
253 	 */
254 	if (change == KVM_MR_FLAGS_ONLY &&
255 	    (!(old->flags & KVM_MEM_LOG_DIRTY_PAGES) &&
256 	     new->flags & KVM_MEM_LOG_DIRTY_PAGES)) {
257 		spin_lock(&kvm->mmu_lock);
258 		/* Write protect GPA page table entries */
259 		needs_flush = kvm_mips_mkclean_gpa_pt(kvm, new->base_gfn,
260 					new->base_gfn + new->npages - 1);
261 		/* Let implementation do the rest */
262 		if (needs_flush)
263 			kvm_mips_callbacks->flush_shadow_memslot(kvm, new);
264 		spin_unlock(&kvm->mmu_lock);
265 	}
266 }
267 
268 static inline void dump_handler(const char *symbol, void *start, void *end)
269 {
270 	u32 *p;
271 
272 	pr_debug("LEAF(%s)\n", symbol);
273 
274 	pr_debug("\t.set push\n");
275 	pr_debug("\t.set noreorder\n");
276 
277 	for (p = start; p < (u32 *)end; ++p)
278 		pr_debug("\t.word\t0x%08x\t\t# %p\n", *p, p);
279 
280 	pr_debug("\t.set\tpop\n");
281 
282 	pr_debug("\tEND(%s)\n", symbol);
283 }
284 
285 /* low level hrtimer wake routine */
286 static enum hrtimer_restart kvm_mips_comparecount_wakeup(struct hrtimer *timer)
287 {
288 	struct kvm_vcpu *vcpu;
289 
290 	vcpu = container_of(timer, struct kvm_vcpu, arch.comparecount_timer);
291 
292 	kvm_mips_callbacks->queue_timer_int(vcpu);
293 
294 	vcpu->arch.wait = 0;
295 	rcuwait_wake_up(&vcpu->wait);
296 
297 	return kvm_mips_count_timeout(vcpu);
298 }
299 
300 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
301 {
302 	return 0;
303 }
304 
305 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
306 {
307 	int err, size;
308 	void *gebase, *p, *handler, *refill_start, *refill_end;
309 	int i;
310 
311 	kvm_debug("kvm @ %p: create cpu %d at %p\n",
312 		  vcpu->kvm, vcpu->vcpu_id, vcpu);
313 
314 	err = kvm_mips_callbacks->vcpu_init(vcpu);
315 	if (err)
316 		return err;
317 
318 	hrtimer_init(&vcpu->arch.comparecount_timer, CLOCK_MONOTONIC,
319 		     HRTIMER_MODE_REL);
320 	vcpu->arch.comparecount_timer.function = kvm_mips_comparecount_wakeup;
321 
322 	/*
323 	 * Allocate space for host mode exception handlers that handle
324 	 * guest mode exits
325 	 */
326 	if (cpu_has_veic || cpu_has_vint)
327 		size = 0x200 + VECTORSPACING * 64;
328 	else
329 		size = 0x4000;
330 
331 	gebase = kzalloc(ALIGN(size, PAGE_SIZE), GFP_KERNEL);
332 
333 	if (!gebase) {
334 		err = -ENOMEM;
335 		goto out_uninit_vcpu;
336 	}
337 	kvm_debug("Allocated %d bytes for KVM Exception Handlers @ %p\n",
338 		  ALIGN(size, PAGE_SIZE), gebase);
339 
340 	/*
341 	 * Check new ebase actually fits in CP0_EBase. The lack of a write gate
342 	 * limits us to the low 512MB of physical address space. If the memory
343 	 * we allocate is out of range, just give up now.
344 	 */
345 	if (!cpu_has_ebase_wg && virt_to_phys(gebase) >= 0x20000000) {
346 		kvm_err("CP0_EBase.WG required for guest exception base %pK\n",
347 			gebase);
348 		err = -ENOMEM;
349 		goto out_free_gebase;
350 	}
351 
352 	/* Save new ebase */
353 	vcpu->arch.guest_ebase = gebase;
354 
355 	/* Build guest exception vectors dynamically in unmapped memory */
356 	handler = gebase + 0x2000;
357 
358 	/* TLB refill (or XTLB refill on 64-bit VZ where KX=1) */
359 	refill_start = gebase;
360 	if (IS_ENABLED(CONFIG_KVM_MIPS_VZ) && IS_ENABLED(CONFIG_64BIT))
361 		refill_start += 0x080;
362 	refill_end = kvm_mips_build_tlb_refill_exception(refill_start, handler);
363 
364 	/* General Exception Entry point */
365 	kvm_mips_build_exception(gebase + 0x180, handler);
366 
367 	/* For vectored interrupts poke the exception code @ all offsets 0-7 */
368 	for (i = 0; i < 8; i++) {
369 		kvm_debug("L1 Vectored handler @ %p\n",
370 			  gebase + 0x200 + (i * VECTORSPACING));
371 		kvm_mips_build_exception(gebase + 0x200 + i * VECTORSPACING,
372 					 handler);
373 	}
374 
375 	/* General exit handler */
376 	p = handler;
377 	p = kvm_mips_build_exit(p);
378 
379 	/* Guest entry routine */
380 	vcpu->arch.vcpu_run = p;
381 	p = kvm_mips_build_vcpu_run(p);
382 
383 	/* Dump the generated code */
384 	pr_debug("#include <asm/asm.h>\n");
385 	pr_debug("#include <asm/regdef.h>\n");
386 	pr_debug("\n");
387 	dump_handler("kvm_vcpu_run", vcpu->arch.vcpu_run, p);
388 	dump_handler("kvm_tlb_refill", refill_start, refill_end);
389 	dump_handler("kvm_gen_exc", gebase + 0x180, gebase + 0x200);
390 	dump_handler("kvm_exit", gebase + 0x2000, vcpu->arch.vcpu_run);
391 
392 	/* Invalidate the icache for these ranges */
393 	flush_icache_range((unsigned long)gebase,
394 			   (unsigned long)gebase + ALIGN(size, PAGE_SIZE));
395 
396 	/*
397 	 * Allocate comm page for guest kernel, a TLB will be reserved for
398 	 * mapping GVA @ 0xFFFF8000 to this page
399 	 */
400 	vcpu->arch.kseg0_commpage = kzalloc(PAGE_SIZE << 1, GFP_KERNEL);
401 
402 	if (!vcpu->arch.kseg0_commpage) {
403 		err = -ENOMEM;
404 		goto out_free_gebase;
405 	}
406 
407 	kvm_debug("Allocated COMM page @ %p\n", vcpu->arch.kseg0_commpage);
408 	kvm_mips_commpage_init(vcpu);
409 
410 	/* Init */
411 	vcpu->arch.last_sched_cpu = -1;
412 	vcpu->arch.last_exec_cpu = -1;
413 
414 	/* Initial guest state */
415 	err = kvm_mips_callbacks->vcpu_setup(vcpu);
416 	if (err)
417 		goto out_free_commpage;
418 
419 	return 0;
420 
421 out_free_commpage:
422 	kfree(vcpu->arch.kseg0_commpage);
423 out_free_gebase:
424 	kfree(gebase);
425 out_uninit_vcpu:
426 	kvm_mips_callbacks->vcpu_uninit(vcpu);
427 	return err;
428 }
429 
430 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
431 {
432 	hrtimer_cancel(&vcpu->arch.comparecount_timer);
433 
434 	kvm_mips_dump_stats(vcpu);
435 
436 	kvm_mmu_free_memory_caches(vcpu);
437 	kfree(vcpu->arch.guest_ebase);
438 	kfree(vcpu->arch.kseg0_commpage);
439 
440 	kvm_mips_callbacks->vcpu_uninit(vcpu);
441 }
442 
443 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
444 					struct kvm_guest_debug *dbg)
445 {
446 	return -ENOIOCTLCMD;
447 }
448 
449 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
450 {
451 	struct kvm_run *run = vcpu->run;
452 	int r = -EINTR;
453 
454 	vcpu_load(vcpu);
455 
456 	kvm_sigset_activate(vcpu);
457 
458 	if (vcpu->mmio_needed) {
459 		if (!vcpu->mmio_is_write)
460 			kvm_mips_complete_mmio_load(vcpu, run);
461 		vcpu->mmio_needed = 0;
462 	}
463 
464 	if (run->immediate_exit)
465 		goto out;
466 
467 	lose_fpu(1);
468 
469 	local_irq_disable();
470 	guest_enter_irqoff();
471 	trace_kvm_enter(vcpu);
472 
473 	/*
474 	 * Make sure the read of VCPU requests in vcpu_run() callback is not
475 	 * reordered ahead of the write to vcpu->mode, or we could miss a TLB
476 	 * flush request while the requester sees the VCPU as outside of guest
477 	 * mode and not needing an IPI.
478 	 */
479 	smp_store_mb(vcpu->mode, IN_GUEST_MODE);
480 
481 	r = kvm_mips_callbacks->vcpu_run(run, vcpu);
482 
483 	trace_kvm_out(vcpu);
484 	guest_exit_irqoff();
485 	local_irq_enable();
486 
487 out:
488 	kvm_sigset_deactivate(vcpu);
489 
490 	vcpu_put(vcpu);
491 	return r;
492 }
493 
494 int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
495 			     struct kvm_mips_interrupt *irq)
496 {
497 	int intr = (int)irq->irq;
498 	struct kvm_vcpu *dvcpu = NULL;
499 
500 	if (intr == kvm_priority_to_irq[MIPS_EXC_INT_IPI_1] ||
501 	    intr == kvm_priority_to_irq[MIPS_EXC_INT_IPI_2] ||
502 	    intr == (-kvm_priority_to_irq[MIPS_EXC_INT_IPI_1]) ||
503 	    intr == (-kvm_priority_to_irq[MIPS_EXC_INT_IPI_2]))
504 		kvm_debug("%s: CPU: %d, INTR: %d\n", __func__, irq->cpu,
505 			  (int)intr);
506 
507 	if (irq->cpu == -1)
508 		dvcpu = vcpu;
509 	else
510 		dvcpu = vcpu->kvm->vcpus[irq->cpu];
511 
512 	if (intr == 2 || intr == 3 || intr == 4 || intr == 6) {
513 		kvm_mips_callbacks->queue_io_int(dvcpu, irq);
514 
515 	} else if (intr == -2 || intr == -3 || intr == -4 || intr == -6) {
516 		kvm_mips_callbacks->dequeue_io_int(dvcpu, irq);
517 	} else {
518 		kvm_err("%s: invalid interrupt ioctl (%d:%d)\n", __func__,
519 			irq->cpu, irq->irq);
520 		return -EINVAL;
521 	}
522 
523 	dvcpu->arch.wait = 0;
524 
525 	rcuwait_wake_up(&dvcpu->wait);
526 
527 	return 0;
528 }
529 
530 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
531 				    struct kvm_mp_state *mp_state)
532 {
533 	return -ENOIOCTLCMD;
534 }
535 
536 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
537 				    struct kvm_mp_state *mp_state)
538 {
539 	return -ENOIOCTLCMD;
540 }
541 
542 static u64 kvm_mips_get_one_regs[] = {
543 	KVM_REG_MIPS_R0,
544 	KVM_REG_MIPS_R1,
545 	KVM_REG_MIPS_R2,
546 	KVM_REG_MIPS_R3,
547 	KVM_REG_MIPS_R4,
548 	KVM_REG_MIPS_R5,
549 	KVM_REG_MIPS_R6,
550 	KVM_REG_MIPS_R7,
551 	KVM_REG_MIPS_R8,
552 	KVM_REG_MIPS_R9,
553 	KVM_REG_MIPS_R10,
554 	KVM_REG_MIPS_R11,
555 	KVM_REG_MIPS_R12,
556 	KVM_REG_MIPS_R13,
557 	KVM_REG_MIPS_R14,
558 	KVM_REG_MIPS_R15,
559 	KVM_REG_MIPS_R16,
560 	KVM_REG_MIPS_R17,
561 	KVM_REG_MIPS_R18,
562 	KVM_REG_MIPS_R19,
563 	KVM_REG_MIPS_R20,
564 	KVM_REG_MIPS_R21,
565 	KVM_REG_MIPS_R22,
566 	KVM_REG_MIPS_R23,
567 	KVM_REG_MIPS_R24,
568 	KVM_REG_MIPS_R25,
569 	KVM_REG_MIPS_R26,
570 	KVM_REG_MIPS_R27,
571 	KVM_REG_MIPS_R28,
572 	KVM_REG_MIPS_R29,
573 	KVM_REG_MIPS_R30,
574 	KVM_REG_MIPS_R31,
575 
576 #ifndef CONFIG_CPU_MIPSR6
577 	KVM_REG_MIPS_HI,
578 	KVM_REG_MIPS_LO,
579 #endif
580 	KVM_REG_MIPS_PC,
581 };
582 
583 static u64 kvm_mips_get_one_regs_fpu[] = {
584 	KVM_REG_MIPS_FCR_IR,
585 	KVM_REG_MIPS_FCR_CSR,
586 };
587 
588 static u64 kvm_mips_get_one_regs_msa[] = {
589 	KVM_REG_MIPS_MSA_IR,
590 	KVM_REG_MIPS_MSA_CSR,
591 };
592 
593 static unsigned long kvm_mips_num_regs(struct kvm_vcpu *vcpu)
594 {
595 	unsigned long ret;
596 
597 	ret = ARRAY_SIZE(kvm_mips_get_one_regs);
598 	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
599 		ret += ARRAY_SIZE(kvm_mips_get_one_regs_fpu) + 48;
600 		/* odd doubles */
601 		if (boot_cpu_data.fpu_id & MIPS_FPIR_F64)
602 			ret += 16;
603 	}
604 	if (kvm_mips_guest_can_have_msa(&vcpu->arch))
605 		ret += ARRAY_SIZE(kvm_mips_get_one_regs_msa) + 32;
606 	ret += kvm_mips_callbacks->num_regs(vcpu);
607 
608 	return ret;
609 }
610 
611 static int kvm_mips_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices)
612 {
613 	u64 index;
614 	unsigned int i;
615 
616 	if (copy_to_user(indices, kvm_mips_get_one_regs,
617 			 sizeof(kvm_mips_get_one_regs)))
618 		return -EFAULT;
619 	indices += ARRAY_SIZE(kvm_mips_get_one_regs);
620 
621 	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
622 		if (copy_to_user(indices, kvm_mips_get_one_regs_fpu,
623 				 sizeof(kvm_mips_get_one_regs_fpu)))
624 			return -EFAULT;
625 		indices += ARRAY_SIZE(kvm_mips_get_one_regs_fpu);
626 
627 		for (i = 0; i < 32; ++i) {
628 			index = KVM_REG_MIPS_FPR_32(i);
629 			if (copy_to_user(indices, &index, sizeof(index)))
630 				return -EFAULT;
631 			++indices;
632 
633 			/* skip odd doubles if no F64 */
634 			if (i & 1 && !(boot_cpu_data.fpu_id & MIPS_FPIR_F64))
635 				continue;
636 
637 			index = KVM_REG_MIPS_FPR_64(i);
638 			if (copy_to_user(indices, &index, sizeof(index)))
639 				return -EFAULT;
640 			++indices;
641 		}
642 	}
643 
644 	if (kvm_mips_guest_can_have_msa(&vcpu->arch)) {
645 		if (copy_to_user(indices, kvm_mips_get_one_regs_msa,
646 				 sizeof(kvm_mips_get_one_regs_msa)))
647 			return -EFAULT;
648 		indices += ARRAY_SIZE(kvm_mips_get_one_regs_msa);
649 
650 		for (i = 0; i < 32; ++i) {
651 			index = KVM_REG_MIPS_VEC_128(i);
652 			if (copy_to_user(indices, &index, sizeof(index)))
653 				return -EFAULT;
654 			++indices;
655 		}
656 	}
657 
658 	return kvm_mips_callbacks->copy_reg_indices(vcpu, indices);
659 }
660 
661 static int kvm_mips_get_reg(struct kvm_vcpu *vcpu,
662 			    const struct kvm_one_reg *reg)
663 {
664 	struct mips_coproc *cop0 = vcpu->arch.cop0;
665 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
666 	int ret;
667 	s64 v;
668 	s64 vs[2];
669 	unsigned int idx;
670 
671 	switch (reg->id) {
672 	/* General purpose registers */
673 	case KVM_REG_MIPS_R0 ... KVM_REG_MIPS_R31:
674 		v = (long)vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0];
675 		break;
676 #ifndef CONFIG_CPU_MIPSR6
677 	case KVM_REG_MIPS_HI:
678 		v = (long)vcpu->arch.hi;
679 		break;
680 	case KVM_REG_MIPS_LO:
681 		v = (long)vcpu->arch.lo;
682 		break;
683 #endif
684 	case KVM_REG_MIPS_PC:
685 		v = (long)vcpu->arch.pc;
686 		break;
687 
688 	/* Floating point registers */
689 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
690 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
691 			return -EINVAL;
692 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
693 		/* Odd singles in top of even double when FR=0 */
694 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
695 			v = get_fpr32(&fpu->fpr[idx], 0);
696 		else
697 			v = get_fpr32(&fpu->fpr[idx & ~1], idx & 1);
698 		break;
699 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
700 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
701 			return -EINVAL;
702 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
703 		/* Can't access odd doubles in FR=0 mode */
704 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
705 			return -EINVAL;
706 		v = get_fpr64(&fpu->fpr[idx], 0);
707 		break;
708 	case KVM_REG_MIPS_FCR_IR:
709 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
710 			return -EINVAL;
711 		v = boot_cpu_data.fpu_id;
712 		break;
713 	case KVM_REG_MIPS_FCR_CSR:
714 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
715 			return -EINVAL;
716 		v = fpu->fcr31;
717 		break;
718 
719 	/* MIPS SIMD Architecture (MSA) registers */
720 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
721 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
722 			return -EINVAL;
723 		/* Can't access MSA registers in FR=0 mode */
724 		if (!(kvm_read_c0_guest_status(cop0) & ST0_FR))
725 			return -EINVAL;
726 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
727 #ifdef CONFIG_CPU_LITTLE_ENDIAN
728 		/* least significant byte first */
729 		vs[0] = get_fpr64(&fpu->fpr[idx], 0);
730 		vs[1] = get_fpr64(&fpu->fpr[idx], 1);
731 #else
732 		/* most significant byte first */
733 		vs[0] = get_fpr64(&fpu->fpr[idx], 1);
734 		vs[1] = get_fpr64(&fpu->fpr[idx], 0);
735 #endif
736 		break;
737 	case KVM_REG_MIPS_MSA_IR:
738 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
739 			return -EINVAL;
740 		v = boot_cpu_data.msa_id;
741 		break;
742 	case KVM_REG_MIPS_MSA_CSR:
743 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
744 			return -EINVAL;
745 		v = fpu->msacsr;
746 		break;
747 
748 	/* registers to be handled specially */
749 	default:
750 		ret = kvm_mips_callbacks->get_one_reg(vcpu, reg, &v);
751 		if (ret)
752 			return ret;
753 		break;
754 	}
755 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
756 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
757 
758 		return put_user(v, uaddr64);
759 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
760 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
761 		u32 v32 = (u32)v;
762 
763 		return put_user(v32, uaddr32);
764 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
765 		void __user *uaddr = (void __user *)(long)reg->addr;
766 
767 		return copy_to_user(uaddr, vs, 16) ? -EFAULT : 0;
768 	} else {
769 		return -EINVAL;
770 	}
771 }
772 
773 static int kvm_mips_set_reg(struct kvm_vcpu *vcpu,
774 			    const struct kvm_one_reg *reg)
775 {
776 	struct mips_coproc *cop0 = vcpu->arch.cop0;
777 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
778 	s64 v;
779 	s64 vs[2];
780 	unsigned int idx;
781 
782 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
783 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
784 
785 		if (get_user(v, uaddr64) != 0)
786 			return -EFAULT;
787 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
788 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
789 		s32 v32;
790 
791 		if (get_user(v32, uaddr32) != 0)
792 			return -EFAULT;
793 		v = (s64)v32;
794 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
795 		void __user *uaddr = (void __user *)(long)reg->addr;
796 
797 		return copy_from_user(vs, uaddr, 16) ? -EFAULT : 0;
798 	} else {
799 		return -EINVAL;
800 	}
801 
802 	switch (reg->id) {
803 	/* General purpose registers */
804 	case KVM_REG_MIPS_R0:
805 		/* Silently ignore requests to set $0 */
806 		break;
807 	case KVM_REG_MIPS_R1 ... KVM_REG_MIPS_R31:
808 		vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0] = v;
809 		break;
810 #ifndef CONFIG_CPU_MIPSR6
811 	case KVM_REG_MIPS_HI:
812 		vcpu->arch.hi = v;
813 		break;
814 	case KVM_REG_MIPS_LO:
815 		vcpu->arch.lo = v;
816 		break;
817 #endif
818 	case KVM_REG_MIPS_PC:
819 		vcpu->arch.pc = v;
820 		break;
821 
822 	/* Floating point registers */
823 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
824 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
825 			return -EINVAL;
826 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
827 		/* Odd singles in top of even double when FR=0 */
828 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
829 			set_fpr32(&fpu->fpr[idx], 0, v);
830 		else
831 			set_fpr32(&fpu->fpr[idx & ~1], idx & 1, v);
832 		break;
833 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
834 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
835 			return -EINVAL;
836 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
837 		/* Can't access odd doubles in FR=0 mode */
838 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
839 			return -EINVAL;
840 		set_fpr64(&fpu->fpr[idx], 0, v);
841 		break;
842 	case KVM_REG_MIPS_FCR_IR:
843 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
844 			return -EINVAL;
845 		/* Read-only */
846 		break;
847 	case KVM_REG_MIPS_FCR_CSR:
848 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
849 			return -EINVAL;
850 		fpu->fcr31 = v;
851 		break;
852 
853 	/* MIPS SIMD Architecture (MSA) registers */
854 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
855 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
856 			return -EINVAL;
857 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
858 #ifdef CONFIG_CPU_LITTLE_ENDIAN
859 		/* least significant byte first */
860 		set_fpr64(&fpu->fpr[idx], 0, vs[0]);
861 		set_fpr64(&fpu->fpr[idx], 1, vs[1]);
862 #else
863 		/* most significant byte first */
864 		set_fpr64(&fpu->fpr[idx], 1, vs[0]);
865 		set_fpr64(&fpu->fpr[idx], 0, vs[1]);
866 #endif
867 		break;
868 	case KVM_REG_MIPS_MSA_IR:
869 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
870 			return -EINVAL;
871 		/* Read-only */
872 		break;
873 	case KVM_REG_MIPS_MSA_CSR:
874 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
875 			return -EINVAL;
876 		fpu->msacsr = v;
877 		break;
878 
879 	/* registers to be handled specially */
880 	default:
881 		return kvm_mips_callbacks->set_one_reg(vcpu, reg, v);
882 	}
883 	return 0;
884 }
885 
886 static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
887 				     struct kvm_enable_cap *cap)
888 {
889 	int r = 0;
890 
891 	if (!kvm_vm_ioctl_check_extension(vcpu->kvm, cap->cap))
892 		return -EINVAL;
893 	if (cap->flags)
894 		return -EINVAL;
895 	if (cap->args[0])
896 		return -EINVAL;
897 
898 	switch (cap->cap) {
899 	case KVM_CAP_MIPS_FPU:
900 		vcpu->arch.fpu_enabled = true;
901 		break;
902 	case KVM_CAP_MIPS_MSA:
903 		vcpu->arch.msa_enabled = true;
904 		break;
905 	default:
906 		r = -EINVAL;
907 		break;
908 	}
909 
910 	return r;
911 }
912 
913 long kvm_arch_vcpu_async_ioctl(struct file *filp, unsigned int ioctl,
914 			       unsigned long arg)
915 {
916 	struct kvm_vcpu *vcpu = filp->private_data;
917 	void __user *argp = (void __user *)arg;
918 
919 	if (ioctl == KVM_INTERRUPT) {
920 		struct kvm_mips_interrupt irq;
921 
922 		if (copy_from_user(&irq, argp, sizeof(irq)))
923 			return -EFAULT;
924 		kvm_debug("[%d] %s: irq: %d\n", vcpu->vcpu_id, __func__,
925 			  irq.irq);
926 
927 		return kvm_vcpu_ioctl_interrupt(vcpu, &irq);
928 	}
929 
930 	return -ENOIOCTLCMD;
931 }
932 
933 long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl,
934 			 unsigned long arg)
935 {
936 	struct kvm_vcpu *vcpu = filp->private_data;
937 	void __user *argp = (void __user *)arg;
938 	long r;
939 
940 	vcpu_load(vcpu);
941 
942 	switch (ioctl) {
943 	case KVM_SET_ONE_REG:
944 	case KVM_GET_ONE_REG: {
945 		struct kvm_one_reg reg;
946 
947 		r = -EFAULT;
948 		if (copy_from_user(&reg, argp, sizeof(reg)))
949 			break;
950 		if (ioctl == KVM_SET_ONE_REG)
951 			r = kvm_mips_set_reg(vcpu, &reg);
952 		else
953 			r = kvm_mips_get_reg(vcpu, &reg);
954 		break;
955 	}
956 	case KVM_GET_REG_LIST: {
957 		struct kvm_reg_list __user *user_list = argp;
958 		struct kvm_reg_list reg_list;
959 		unsigned n;
960 
961 		r = -EFAULT;
962 		if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
963 			break;
964 		n = reg_list.n;
965 		reg_list.n = kvm_mips_num_regs(vcpu);
966 		if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
967 			break;
968 		r = -E2BIG;
969 		if (n < reg_list.n)
970 			break;
971 		r = kvm_mips_copy_reg_indices(vcpu, user_list->reg);
972 		break;
973 	}
974 	case KVM_ENABLE_CAP: {
975 		struct kvm_enable_cap cap;
976 
977 		r = -EFAULT;
978 		if (copy_from_user(&cap, argp, sizeof(cap)))
979 			break;
980 		r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
981 		break;
982 	}
983 	default:
984 		r = -ENOIOCTLCMD;
985 	}
986 
987 	vcpu_put(vcpu);
988 	return r;
989 }
990 
991 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
992 {
993 
994 }
995 
996 void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
997 					struct kvm_memory_slot *memslot)
998 {
999 	/* Let implementation handle TLB/GVA invalidation */
1000 	kvm_mips_callbacks->flush_shadow_memslot(kvm, memslot);
1001 }
1002 
1003 long kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
1004 {
1005 	long r;
1006 
1007 	switch (ioctl) {
1008 	default:
1009 		r = -ENOIOCTLCMD;
1010 	}
1011 
1012 	return r;
1013 }
1014 
1015 int kvm_arch_init(void *opaque)
1016 {
1017 	if (kvm_mips_callbacks) {
1018 		kvm_err("kvm: module already exists\n");
1019 		return -EEXIST;
1020 	}
1021 
1022 	return kvm_mips_emulation_init(&kvm_mips_callbacks);
1023 }
1024 
1025 void kvm_arch_exit(void)
1026 {
1027 	kvm_mips_callbacks = NULL;
1028 }
1029 
1030 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
1031 				  struct kvm_sregs *sregs)
1032 {
1033 	return -ENOIOCTLCMD;
1034 }
1035 
1036 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
1037 				  struct kvm_sregs *sregs)
1038 {
1039 	return -ENOIOCTLCMD;
1040 }
1041 
1042 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
1043 {
1044 }
1045 
1046 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1047 {
1048 	return -ENOIOCTLCMD;
1049 }
1050 
1051 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1052 {
1053 	return -ENOIOCTLCMD;
1054 }
1055 
1056 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
1057 {
1058 	return VM_FAULT_SIGBUS;
1059 }
1060 
1061 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
1062 {
1063 	int r;
1064 
1065 	switch (ext) {
1066 	case KVM_CAP_ONE_REG:
1067 	case KVM_CAP_ENABLE_CAP:
1068 	case KVM_CAP_READONLY_MEM:
1069 	case KVM_CAP_SYNC_MMU:
1070 	case KVM_CAP_IMMEDIATE_EXIT:
1071 		r = 1;
1072 		break;
1073 	case KVM_CAP_NR_VCPUS:
1074 		r = num_online_cpus();
1075 		break;
1076 	case KVM_CAP_MAX_VCPUS:
1077 		r = KVM_MAX_VCPUS;
1078 		break;
1079 	case KVM_CAP_MAX_VCPU_ID:
1080 		r = KVM_MAX_VCPU_ID;
1081 		break;
1082 	case KVM_CAP_MIPS_FPU:
1083 		/* We don't handle systems with inconsistent cpu_has_fpu */
1084 		r = !!raw_cpu_has_fpu;
1085 		break;
1086 	case KVM_CAP_MIPS_MSA:
1087 		/*
1088 		 * We don't support MSA vector partitioning yet:
1089 		 * 1) It would require explicit support which can't be tested
1090 		 *    yet due to lack of support in current hardware.
1091 		 * 2) It extends the state that would need to be saved/restored
1092 		 *    by e.g. QEMU for migration.
1093 		 *
1094 		 * When vector partitioning hardware becomes available, support
1095 		 * could be added by requiring a flag when enabling
1096 		 * KVM_CAP_MIPS_MSA capability to indicate that userland knows
1097 		 * to save/restore the appropriate extra state.
1098 		 */
1099 		r = cpu_has_msa && !(boot_cpu_data.msa_id & MSA_IR_WRPF);
1100 		break;
1101 	default:
1102 		r = kvm_mips_callbacks->check_extension(kvm, ext);
1103 		break;
1104 	}
1105 	return r;
1106 }
1107 
1108 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
1109 {
1110 	return kvm_mips_pending_timer(vcpu) ||
1111 		kvm_read_c0_guest_cause(vcpu->arch.cop0) & C_TI;
1112 }
1113 
1114 int kvm_arch_vcpu_dump_regs(struct kvm_vcpu *vcpu)
1115 {
1116 	int i;
1117 	struct mips_coproc *cop0;
1118 
1119 	if (!vcpu)
1120 		return -1;
1121 
1122 	kvm_debug("VCPU Register Dump:\n");
1123 	kvm_debug("\tpc = 0x%08lx\n", vcpu->arch.pc);
1124 	kvm_debug("\texceptions: %08lx\n", vcpu->arch.pending_exceptions);
1125 
1126 	for (i = 0; i < 32; i += 4) {
1127 		kvm_debug("\tgpr%02d: %08lx %08lx %08lx %08lx\n", i,
1128 		       vcpu->arch.gprs[i],
1129 		       vcpu->arch.gprs[i + 1],
1130 		       vcpu->arch.gprs[i + 2], vcpu->arch.gprs[i + 3]);
1131 	}
1132 	kvm_debug("\thi: 0x%08lx\n", vcpu->arch.hi);
1133 	kvm_debug("\tlo: 0x%08lx\n", vcpu->arch.lo);
1134 
1135 	cop0 = vcpu->arch.cop0;
1136 	kvm_debug("\tStatus: 0x%08x, Cause: 0x%08x\n",
1137 		  kvm_read_c0_guest_status(cop0),
1138 		  kvm_read_c0_guest_cause(cop0));
1139 
1140 	kvm_debug("\tEPC: 0x%08lx\n", kvm_read_c0_guest_epc(cop0));
1141 
1142 	return 0;
1143 }
1144 
1145 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1146 {
1147 	int i;
1148 
1149 	vcpu_load(vcpu);
1150 
1151 	for (i = 1; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1152 		vcpu->arch.gprs[i] = regs->gpr[i];
1153 	vcpu->arch.gprs[0] = 0; /* zero is special, and cannot be set. */
1154 	vcpu->arch.hi = regs->hi;
1155 	vcpu->arch.lo = regs->lo;
1156 	vcpu->arch.pc = regs->pc;
1157 
1158 	vcpu_put(vcpu);
1159 	return 0;
1160 }
1161 
1162 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1163 {
1164 	int i;
1165 
1166 	vcpu_load(vcpu);
1167 
1168 	for (i = 0; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1169 		regs->gpr[i] = vcpu->arch.gprs[i];
1170 
1171 	regs->hi = vcpu->arch.hi;
1172 	regs->lo = vcpu->arch.lo;
1173 	regs->pc = vcpu->arch.pc;
1174 
1175 	vcpu_put(vcpu);
1176 	return 0;
1177 }
1178 
1179 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
1180 				  struct kvm_translation *tr)
1181 {
1182 	return 0;
1183 }
1184 
1185 static void kvm_mips_set_c0_status(void)
1186 {
1187 	u32 status = read_c0_status();
1188 
1189 	if (cpu_has_dsp)
1190 		status |= (ST0_MX);
1191 
1192 	write_c0_status(status);
1193 	ehb();
1194 }
1195 
1196 /*
1197  * Return value is in the form (errcode<<2 | RESUME_FLAG_HOST | RESUME_FLAG_NV)
1198  */
1199 int kvm_mips_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu)
1200 {
1201 	u32 cause = vcpu->arch.host_cp0_cause;
1202 	u32 exccode = (cause >> CAUSEB_EXCCODE) & 0x1f;
1203 	u32 __user *opc = (u32 __user *) vcpu->arch.pc;
1204 	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
1205 	enum emulation_result er = EMULATE_DONE;
1206 	u32 inst;
1207 	int ret = RESUME_GUEST;
1208 
1209 	vcpu->mode = OUTSIDE_GUEST_MODE;
1210 
1211 	/* re-enable HTW before enabling interrupts */
1212 	if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ))
1213 		htw_start();
1214 
1215 	/* Set a default exit reason */
1216 	run->exit_reason = KVM_EXIT_UNKNOWN;
1217 	run->ready_for_interrupt_injection = 1;
1218 
1219 	/*
1220 	 * Set the appropriate status bits based on host CPU features,
1221 	 * before we hit the scheduler
1222 	 */
1223 	kvm_mips_set_c0_status();
1224 
1225 	local_irq_enable();
1226 
1227 	kvm_debug("kvm_mips_handle_exit: cause: %#x, PC: %p, kvm_run: %p, kvm_vcpu: %p\n",
1228 			cause, opc, run, vcpu);
1229 	trace_kvm_exit(vcpu, exccode);
1230 
1231 	if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) {
1232 		/*
1233 		 * Do a privilege check, if in UM most of these exit conditions
1234 		 * end up causing an exception to be delivered to the Guest
1235 		 * Kernel
1236 		 */
1237 		er = kvm_mips_check_privilege(cause, opc, run, vcpu);
1238 		if (er == EMULATE_PRIV_FAIL) {
1239 			goto skip_emul;
1240 		} else if (er == EMULATE_FAIL) {
1241 			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1242 			ret = RESUME_HOST;
1243 			goto skip_emul;
1244 		}
1245 	}
1246 
1247 	switch (exccode) {
1248 	case EXCCODE_INT:
1249 		kvm_debug("[%d]EXCCODE_INT @ %p\n", vcpu->vcpu_id, opc);
1250 
1251 		++vcpu->stat.int_exits;
1252 
1253 		if (need_resched())
1254 			cond_resched();
1255 
1256 		ret = RESUME_GUEST;
1257 		break;
1258 
1259 	case EXCCODE_CPU:
1260 		kvm_debug("EXCCODE_CPU: @ PC: %p\n", opc);
1261 
1262 		++vcpu->stat.cop_unusable_exits;
1263 		ret = kvm_mips_callbacks->handle_cop_unusable(vcpu);
1264 		/* XXXKYMA: Might need to return to user space */
1265 		if (run->exit_reason == KVM_EXIT_IRQ_WINDOW_OPEN)
1266 			ret = RESUME_HOST;
1267 		break;
1268 
1269 	case EXCCODE_MOD:
1270 		++vcpu->stat.tlbmod_exits;
1271 		ret = kvm_mips_callbacks->handle_tlb_mod(vcpu);
1272 		break;
1273 
1274 	case EXCCODE_TLBS:
1275 		kvm_debug("TLB ST fault:  cause %#x, status %#x, PC: %p, BadVaddr: %#lx\n",
1276 			  cause, kvm_read_c0_guest_status(vcpu->arch.cop0), opc,
1277 			  badvaddr);
1278 
1279 		++vcpu->stat.tlbmiss_st_exits;
1280 		ret = kvm_mips_callbacks->handle_tlb_st_miss(vcpu);
1281 		break;
1282 
1283 	case EXCCODE_TLBL:
1284 		kvm_debug("TLB LD fault: cause %#x, PC: %p, BadVaddr: %#lx\n",
1285 			  cause, opc, badvaddr);
1286 
1287 		++vcpu->stat.tlbmiss_ld_exits;
1288 		ret = kvm_mips_callbacks->handle_tlb_ld_miss(vcpu);
1289 		break;
1290 
1291 	case EXCCODE_ADES:
1292 		++vcpu->stat.addrerr_st_exits;
1293 		ret = kvm_mips_callbacks->handle_addr_err_st(vcpu);
1294 		break;
1295 
1296 	case EXCCODE_ADEL:
1297 		++vcpu->stat.addrerr_ld_exits;
1298 		ret = kvm_mips_callbacks->handle_addr_err_ld(vcpu);
1299 		break;
1300 
1301 	case EXCCODE_SYS:
1302 		++vcpu->stat.syscall_exits;
1303 		ret = kvm_mips_callbacks->handle_syscall(vcpu);
1304 		break;
1305 
1306 	case EXCCODE_RI:
1307 		++vcpu->stat.resvd_inst_exits;
1308 		ret = kvm_mips_callbacks->handle_res_inst(vcpu);
1309 		break;
1310 
1311 	case EXCCODE_BP:
1312 		++vcpu->stat.break_inst_exits;
1313 		ret = kvm_mips_callbacks->handle_break(vcpu);
1314 		break;
1315 
1316 	case EXCCODE_TR:
1317 		++vcpu->stat.trap_inst_exits;
1318 		ret = kvm_mips_callbacks->handle_trap(vcpu);
1319 		break;
1320 
1321 	case EXCCODE_MSAFPE:
1322 		++vcpu->stat.msa_fpe_exits;
1323 		ret = kvm_mips_callbacks->handle_msa_fpe(vcpu);
1324 		break;
1325 
1326 	case EXCCODE_FPE:
1327 		++vcpu->stat.fpe_exits;
1328 		ret = kvm_mips_callbacks->handle_fpe(vcpu);
1329 		break;
1330 
1331 	case EXCCODE_MSADIS:
1332 		++vcpu->stat.msa_disabled_exits;
1333 		ret = kvm_mips_callbacks->handle_msa_disabled(vcpu);
1334 		break;
1335 
1336 	case EXCCODE_GE:
1337 		/* defer exit accounting to handler */
1338 		ret = kvm_mips_callbacks->handle_guest_exit(vcpu);
1339 		break;
1340 
1341 	default:
1342 		if (cause & CAUSEF_BD)
1343 			opc += 1;
1344 		inst = 0;
1345 		kvm_get_badinstr(opc, vcpu, &inst);
1346 		kvm_err("Exception Code: %d, not yet handled, @ PC: %p, inst: 0x%08x  BadVaddr: %#lx Status: %#x\n",
1347 			exccode, opc, inst, badvaddr,
1348 			kvm_read_c0_guest_status(vcpu->arch.cop0));
1349 		kvm_arch_vcpu_dump_regs(vcpu);
1350 		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1351 		ret = RESUME_HOST;
1352 		break;
1353 
1354 	}
1355 
1356 skip_emul:
1357 	local_irq_disable();
1358 
1359 	if (ret == RESUME_GUEST)
1360 		kvm_vz_acquire_htimer(vcpu);
1361 
1362 	if (er == EMULATE_DONE && !(ret & RESUME_HOST))
1363 		kvm_mips_deliver_interrupts(vcpu, cause);
1364 
1365 	if (!(ret & RESUME_HOST)) {
1366 		/* Only check for signals if not already exiting to userspace */
1367 		if (signal_pending(current)) {
1368 			run->exit_reason = KVM_EXIT_INTR;
1369 			ret = (-EINTR << 2) | RESUME_HOST;
1370 			++vcpu->stat.signal_exits;
1371 			trace_kvm_exit(vcpu, KVM_TRACE_EXIT_SIGNAL);
1372 		}
1373 	}
1374 
1375 	if (ret == RESUME_GUEST) {
1376 		trace_kvm_reenter(vcpu);
1377 
1378 		/*
1379 		 * Make sure the read of VCPU requests in vcpu_reenter()
1380 		 * callback is not reordered ahead of the write to vcpu->mode,
1381 		 * or we could miss a TLB flush request while the requester sees
1382 		 * the VCPU as outside of guest mode and not needing an IPI.
1383 		 */
1384 		smp_store_mb(vcpu->mode, IN_GUEST_MODE);
1385 
1386 		kvm_mips_callbacks->vcpu_reenter(run, vcpu);
1387 
1388 		/*
1389 		 * If FPU / MSA are enabled (i.e. the guest's FPU / MSA context
1390 		 * is live), restore FCR31 / MSACSR.
1391 		 *
1392 		 * This should be before returning to the guest exception
1393 		 * vector, as it may well cause an [MSA] FP exception if there
1394 		 * are pending exception bits unmasked. (see
1395 		 * kvm_mips_csr_die_notifier() for how that is handled).
1396 		 */
1397 		if (kvm_mips_guest_has_fpu(&vcpu->arch) &&
1398 		    read_c0_status() & ST0_CU1)
1399 			__kvm_restore_fcsr(&vcpu->arch);
1400 
1401 		if (kvm_mips_guest_has_msa(&vcpu->arch) &&
1402 		    read_c0_config5() & MIPS_CONF5_MSAEN)
1403 			__kvm_restore_msacsr(&vcpu->arch);
1404 	}
1405 
1406 	/* Disable HTW before returning to guest or host */
1407 	if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ))
1408 		htw_stop();
1409 
1410 	return ret;
1411 }
1412 
1413 /* Enable FPU for guest and restore context */
1414 void kvm_own_fpu(struct kvm_vcpu *vcpu)
1415 {
1416 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1417 	unsigned int sr, cfg5;
1418 
1419 	preempt_disable();
1420 
1421 	sr = kvm_read_c0_guest_status(cop0);
1422 
1423 	/*
1424 	 * If MSA state is already live, it is undefined how it interacts with
1425 	 * FR=0 FPU state, and we don't want to hit reserved instruction
1426 	 * exceptions trying to save the MSA state later when CU=1 && FR=1, so
1427 	 * play it safe and save it first.
1428 	 *
1429 	 * In theory we shouldn't ever hit this case since kvm_lose_fpu() should
1430 	 * get called when guest CU1 is set, however we can't trust the guest
1431 	 * not to clobber the status register directly via the commpage.
1432 	 */
1433 	if (cpu_has_msa && sr & ST0_CU1 && !(sr & ST0_FR) &&
1434 	    vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA)
1435 		kvm_lose_fpu(vcpu);
1436 
1437 	/*
1438 	 * Enable FPU for guest
1439 	 * We set FR and FRE according to guest context
1440 	 */
1441 	change_c0_status(ST0_CU1 | ST0_FR, sr);
1442 	if (cpu_has_fre) {
1443 		cfg5 = kvm_read_c0_guest_config5(cop0);
1444 		change_c0_config5(MIPS_CONF5_FRE, cfg5);
1445 	}
1446 	enable_fpu_hazard();
1447 
1448 	/* If guest FPU state not active, restore it now */
1449 	if (!(vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU)) {
1450 		__kvm_restore_fpu(&vcpu->arch);
1451 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1452 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_FPU);
1453 	} else {
1454 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_FPU);
1455 	}
1456 
1457 	preempt_enable();
1458 }
1459 
1460 #ifdef CONFIG_CPU_HAS_MSA
1461 /* Enable MSA for guest and restore context */
1462 void kvm_own_msa(struct kvm_vcpu *vcpu)
1463 {
1464 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1465 	unsigned int sr, cfg5;
1466 
1467 	preempt_disable();
1468 
1469 	/*
1470 	 * Enable FPU if enabled in guest, since we're restoring FPU context
1471 	 * anyway. We set FR and FRE according to guest context.
1472 	 */
1473 	if (kvm_mips_guest_has_fpu(&vcpu->arch)) {
1474 		sr = kvm_read_c0_guest_status(cop0);
1475 
1476 		/*
1477 		 * If FR=0 FPU state is already live, it is undefined how it
1478 		 * interacts with MSA state, so play it safe and save it first.
1479 		 */
1480 		if (!(sr & ST0_FR) &&
1481 		    (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU |
1482 				KVM_MIPS_AUX_MSA)) == KVM_MIPS_AUX_FPU)
1483 			kvm_lose_fpu(vcpu);
1484 
1485 		change_c0_status(ST0_CU1 | ST0_FR, sr);
1486 		if (sr & ST0_CU1 && cpu_has_fre) {
1487 			cfg5 = kvm_read_c0_guest_config5(cop0);
1488 			change_c0_config5(MIPS_CONF5_FRE, cfg5);
1489 		}
1490 	}
1491 
1492 	/* Enable MSA for guest */
1493 	set_c0_config5(MIPS_CONF5_MSAEN);
1494 	enable_fpu_hazard();
1495 
1496 	switch (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA)) {
1497 	case KVM_MIPS_AUX_FPU:
1498 		/*
1499 		 * Guest FPU state already loaded, only restore upper MSA state
1500 		 */
1501 		__kvm_restore_msa_upper(&vcpu->arch);
1502 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1503 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_MSA);
1504 		break;
1505 	case 0:
1506 		/* Neither FPU or MSA already active, restore full MSA state */
1507 		__kvm_restore_msa(&vcpu->arch);
1508 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1509 		if (kvm_mips_guest_has_fpu(&vcpu->arch))
1510 			vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1511 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE,
1512 			      KVM_TRACE_AUX_FPU_MSA);
1513 		break;
1514 	default:
1515 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_MSA);
1516 		break;
1517 	}
1518 
1519 	preempt_enable();
1520 }
1521 #endif
1522 
1523 /* Drop FPU & MSA without saving it */
1524 void kvm_drop_fpu(struct kvm_vcpu *vcpu)
1525 {
1526 	preempt_disable();
1527 	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1528 		disable_msa();
1529 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_MSA);
1530 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_MSA;
1531 	}
1532 	if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1533 		clear_c0_status(ST0_CU1 | ST0_FR);
1534 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_FPU);
1535 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1536 	}
1537 	preempt_enable();
1538 }
1539 
1540 /* Save and disable FPU & MSA */
1541 void kvm_lose_fpu(struct kvm_vcpu *vcpu)
1542 {
1543 	/*
1544 	 * With T&E, FPU & MSA get disabled in root context (hardware) when it
1545 	 * is disabled in guest context (software), but the register state in
1546 	 * the hardware may still be in use.
1547 	 * This is why we explicitly re-enable the hardware before saving.
1548 	 */
1549 
1550 	preempt_disable();
1551 	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1552 		if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) {
1553 			set_c0_config5(MIPS_CONF5_MSAEN);
1554 			enable_fpu_hazard();
1555 		}
1556 
1557 		__kvm_save_msa(&vcpu->arch);
1558 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU_MSA);
1559 
1560 		/* Disable MSA & FPU */
1561 		disable_msa();
1562 		if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1563 			clear_c0_status(ST0_CU1 | ST0_FR);
1564 			disable_fpu_hazard();
1565 		}
1566 		vcpu->arch.aux_inuse &= ~(KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA);
1567 	} else if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1568 		if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) {
1569 			set_c0_status(ST0_CU1);
1570 			enable_fpu_hazard();
1571 		}
1572 
1573 		__kvm_save_fpu(&vcpu->arch);
1574 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1575 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU);
1576 
1577 		/* Disable FPU */
1578 		clear_c0_status(ST0_CU1 | ST0_FR);
1579 		disable_fpu_hazard();
1580 	}
1581 	preempt_enable();
1582 }
1583 
1584 /*
1585  * Step over a specific ctc1 to FCSR and a specific ctcmsa to MSACSR which are
1586  * used to restore guest FCSR/MSACSR state and may trigger a "harmless" FP/MSAFP
1587  * exception if cause bits are set in the value being written.
1588  */
1589 static int kvm_mips_csr_die_notify(struct notifier_block *self,
1590 				   unsigned long cmd, void *ptr)
1591 {
1592 	struct die_args *args = (struct die_args *)ptr;
1593 	struct pt_regs *regs = args->regs;
1594 	unsigned long pc;
1595 
1596 	/* Only interested in FPE and MSAFPE */
1597 	if (cmd != DIE_FP && cmd != DIE_MSAFP)
1598 		return NOTIFY_DONE;
1599 
1600 	/* Return immediately if guest context isn't active */
1601 	if (!(current->flags & PF_VCPU))
1602 		return NOTIFY_DONE;
1603 
1604 	/* Should never get here from user mode */
1605 	BUG_ON(user_mode(regs));
1606 
1607 	pc = instruction_pointer(regs);
1608 	switch (cmd) {
1609 	case DIE_FP:
1610 		/* match 2nd instruction in __kvm_restore_fcsr */
1611 		if (pc != (unsigned long)&__kvm_restore_fcsr + 4)
1612 			return NOTIFY_DONE;
1613 		break;
1614 	case DIE_MSAFP:
1615 		/* match 2nd/3rd instruction in __kvm_restore_msacsr */
1616 		if (!cpu_has_msa ||
1617 		    pc < (unsigned long)&__kvm_restore_msacsr + 4 ||
1618 		    pc > (unsigned long)&__kvm_restore_msacsr + 8)
1619 			return NOTIFY_DONE;
1620 		break;
1621 	}
1622 
1623 	/* Move PC forward a little and continue executing */
1624 	instruction_pointer(regs) += 4;
1625 
1626 	return NOTIFY_STOP;
1627 }
1628 
1629 static struct notifier_block kvm_mips_csr_die_notifier = {
1630 	.notifier_call = kvm_mips_csr_die_notify,
1631 };
1632 
1633 static u32 kvm_default_priority_to_irq[MIPS_EXC_MAX] = {
1634 	[MIPS_EXC_INT_TIMER] = C_IRQ5,
1635 	[MIPS_EXC_INT_IO_1]  = C_IRQ0,
1636 	[MIPS_EXC_INT_IPI_1] = C_IRQ1,
1637 	[MIPS_EXC_INT_IPI_2] = C_IRQ2,
1638 };
1639 
1640 static u32 kvm_loongson3_priority_to_irq[MIPS_EXC_MAX] = {
1641 	[MIPS_EXC_INT_TIMER] = C_IRQ5,
1642 	[MIPS_EXC_INT_IO_1]  = C_IRQ0,
1643 	[MIPS_EXC_INT_IO_2]  = C_IRQ1,
1644 	[MIPS_EXC_INT_IPI_1] = C_IRQ4,
1645 };
1646 
1647 u32 *kvm_priority_to_irq = kvm_default_priority_to_irq;
1648 
1649 u32 kvm_irq_to_priority(u32 irq)
1650 {
1651 	int i;
1652 
1653 	for (i = MIPS_EXC_INT_TIMER; i < MIPS_EXC_MAX; i++) {
1654 		if (kvm_priority_to_irq[i] == (1 << (irq + 8)))
1655 			return i;
1656 	}
1657 
1658 	return MIPS_EXC_MAX;
1659 }
1660 
1661 static int __init kvm_mips_init(void)
1662 {
1663 	int ret;
1664 
1665 	if (cpu_has_mmid) {
1666 		pr_warn("KVM does not yet support MMIDs. KVM Disabled\n");
1667 		return -EOPNOTSUPP;
1668 	}
1669 
1670 	ret = kvm_mips_entry_setup();
1671 	if (ret)
1672 		return ret;
1673 
1674 	ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
1675 
1676 	if (ret)
1677 		return ret;
1678 
1679 	if (boot_cpu_type() == CPU_LOONGSON64)
1680 		kvm_priority_to_irq = kvm_loongson3_priority_to_irq;
1681 
1682 	register_die_notifier(&kvm_mips_csr_die_notifier);
1683 
1684 	return 0;
1685 }
1686 
1687 static void __exit kvm_mips_exit(void)
1688 {
1689 	kvm_exit();
1690 
1691 	unregister_die_notifier(&kvm_mips_csr_die_notifier);
1692 }
1693 
1694 module_init(kvm_mips_init);
1695 module_exit(kvm_mips_exit);
1696 
1697 EXPORT_TRACEPOINT_SYMBOL(kvm_exit);
1698