xref: /openbmc/linux/arch/mips/kvm/mips.c (revision b03afaa8)
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 #ifdef CONFIG_KVM_MIPS_VZ
141 	case KVM_VM_MIPS_VZ:
142 #else
143 	case KVM_VM_MIPS_TE:
144 #endif
145 		break;
146 	default:
147 		/* Unsupported KVM type */
148 		return -EINVAL;
149 	};
150 
151 	/* Allocate page table to map GPA -> RPA */
152 	kvm->arch.gpa_mm.pgd = kvm_pgd_alloc();
153 	if (!kvm->arch.gpa_mm.pgd)
154 		return -ENOMEM;
155 
156 #ifdef CONFIG_CPU_LOONGSON64
157 	kvm_init_loongson_ipi(kvm);
158 #endif
159 
160 	return 0;
161 }
162 
163 void kvm_mips_free_vcpus(struct kvm *kvm)
164 {
165 	unsigned int i;
166 	struct kvm_vcpu *vcpu;
167 
168 	kvm_for_each_vcpu(i, vcpu, kvm) {
169 		kvm_vcpu_destroy(vcpu);
170 	}
171 
172 	mutex_lock(&kvm->lock);
173 
174 	for (i = 0; i < atomic_read(&kvm->online_vcpus); i++)
175 		kvm->vcpus[i] = NULL;
176 
177 	atomic_set(&kvm->online_vcpus, 0);
178 
179 	mutex_unlock(&kvm->lock);
180 }
181 
182 static void kvm_mips_free_gpa_pt(struct kvm *kvm)
183 {
184 	/* It should always be safe to remove after flushing the whole range */
185 	WARN_ON(!kvm_mips_flush_gpa_pt(kvm, 0, ~0));
186 	pgd_free(NULL, kvm->arch.gpa_mm.pgd);
187 }
188 
189 void kvm_arch_destroy_vm(struct kvm *kvm)
190 {
191 	kvm_mips_free_vcpus(kvm);
192 	kvm_mips_free_gpa_pt(kvm);
193 }
194 
195 long kvm_arch_dev_ioctl(struct file *filp, unsigned int ioctl,
196 			unsigned long arg)
197 {
198 	return -ENOIOCTLCMD;
199 }
200 
201 void kvm_arch_flush_shadow_all(struct kvm *kvm)
202 {
203 	/* Flush whole GPA */
204 	kvm_mips_flush_gpa_pt(kvm, 0, ~0);
205 
206 	/* Let implementation do the rest */
207 	kvm_mips_callbacks->flush_shadow_all(kvm);
208 }
209 
210 void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
211 				   struct kvm_memory_slot *slot)
212 {
213 	/*
214 	 * The slot has been made invalid (ready for moving or deletion), so we
215 	 * need to ensure that it can no longer be accessed by any guest VCPUs.
216 	 */
217 
218 	spin_lock(&kvm->mmu_lock);
219 	/* Flush slot from GPA */
220 	kvm_mips_flush_gpa_pt(kvm, slot->base_gfn,
221 			      slot->base_gfn + slot->npages - 1);
222 	/* Let implementation do the rest */
223 	kvm_mips_callbacks->flush_shadow_memslot(kvm, slot);
224 	spin_unlock(&kvm->mmu_lock);
225 }
226 
227 int kvm_arch_prepare_memory_region(struct kvm *kvm,
228 				   struct kvm_memory_slot *memslot,
229 				   const struct kvm_userspace_memory_region *mem,
230 				   enum kvm_mr_change change)
231 {
232 	return 0;
233 }
234 
235 void kvm_arch_commit_memory_region(struct kvm *kvm,
236 				   const struct kvm_userspace_memory_region *mem,
237 				   struct kvm_memory_slot *old,
238 				   const struct kvm_memory_slot *new,
239 				   enum kvm_mr_change change)
240 {
241 	int needs_flush;
242 
243 	kvm_debug("%s: kvm: %p slot: %d, GPA: %llx, size: %llx, QVA: %llx\n",
244 		  __func__, kvm, mem->slot, mem->guest_phys_addr,
245 		  mem->memory_size, mem->userspace_addr);
246 
247 	/*
248 	 * If dirty page logging is enabled, write protect all pages in the slot
249 	 * ready for dirty logging.
250 	 *
251 	 * There is no need to do this in any of the following cases:
252 	 * CREATE:	No dirty mappings will already exist.
253 	 * MOVE/DELETE:	The old mappings will already have been cleaned up by
254 	 *		kvm_arch_flush_shadow_memslot()
255 	 */
256 	if (change == KVM_MR_FLAGS_ONLY &&
257 	    (!(old->flags & KVM_MEM_LOG_DIRTY_PAGES) &&
258 	     new->flags & KVM_MEM_LOG_DIRTY_PAGES)) {
259 		spin_lock(&kvm->mmu_lock);
260 		/* Write protect GPA page table entries */
261 		needs_flush = kvm_mips_mkclean_gpa_pt(kvm, new->base_gfn,
262 					new->base_gfn + new->npages - 1);
263 		/* Let implementation do the rest */
264 		if (needs_flush)
265 			kvm_mips_callbacks->flush_shadow_memslot(kvm, new);
266 		spin_unlock(&kvm->mmu_lock);
267 	}
268 }
269 
270 static inline void dump_handler(const char *symbol, void *start, void *end)
271 {
272 	u32 *p;
273 
274 	pr_debug("LEAF(%s)\n", symbol);
275 
276 	pr_debug("\t.set push\n");
277 	pr_debug("\t.set noreorder\n");
278 
279 	for (p = start; p < (u32 *)end; ++p)
280 		pr_debug("\t.word\t0x%08x\t\t# %p\n", *p, p);
281 
282 	pr_debug("\t.set\tpop\n");
283 
284 	pr_debug("\tEND(%s)\n", symbol);
285 }
286 
287 /* low level hrtimer wake routine */
288 static enum hrtimer_restart kvm_mips_comparecount_wakeup(struct hrtimer *timer)
289 {
290 	struct kvm_vcpu *vcpu;
291 
292 	vcpu = container_of(timer, struct kvm_vcpu, arch.comparecount_timer);
293 
294 	kvm_mips_callbacks->queue_timer_int(vcpu);
295 
296 	vcpu->arch.wait = 0;
297 	rcuwait_wake_up(&vcpu->wait);
298 
299 	return kvm_mips_count_timeout(vcpu);
300 }
301 
302 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
303 {
304 	return 0;
305 }
306 
307 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
308 {
309 	int err, size;
310 	void *gebase, *p, *handler, *refill_start, *refill_end;
311 	int i;
312 
313 	kvm_debug("kvm @ %p: create cpu %d at %p\n",
314 		  vcpu->kvm, vcpu->vcpu_id, vcpu);
315 
316 	err = kvm_mips_callbacks->vcpu_init(vcpu);
317 	if (err)
318 		return err;
319 
320 	hrtimer_init(&vcpu->arch.comparecount_timer, CLOCK_MONOTONIC,
321 		     HRTIMER_MODE_REL);
322 	vcpu->arch.comparecount_timer.function = kvm_mips_comparecount_wakeup;
323 
324 	/*
325 	 * Allocate space for host mode exception handlers that handle
326 	 * guest mode exits
327 	 */
328 	if (cpu_has_veic || cpu_has_vint)
329 		size = 0x200 + VECTORSPACING * 64;
330 	else
331 		size = 0x4000;
332 
333 	gebase = kzalloc(ALIGN(size, PAGE_SIZE), GFP_KERNEL);
334 
335 	if (!gebase) {
336 		err = -ENOMEM;
337 		goto out_uninit_vcpu;
338 	}
339 	kvm_debug("Allocated %d bytes for KVM Exception Handlers @ %p\n",
340 		  ALIGN(size, PAGE_SIZE), gebase);
341 
342 	/*
343 	 * Check new ebase actually fits in CP0_EBase. The lack of a write gate
344 	 * limits us to the low 512MB of physical address space. If the memory
345 	 * we allocate is out of range, just give up now.
346 	 */
347 	if (!cpu_has_ebase_wg && virt_to_phys(gebase) >= 0x20000000) {
348 		kvm_err("CP0_EBase.WG required for guest exception base %pK\n",
349 			gebase);
350 		err = -ENOMEM;
351 		goto out_free_gebase;
352 	}
353 
354 	/* Save new ebase */
355 	vcpu->arch.guest_ebase = gebase;
356 
357 	/* Build guest exception vectors dynamically in unmapped memory */
358 	handler = gebase + 0x2000;
359 
360 	/* TLB refill (or XTLB refill on 64-bit VZ where KX=1) */
361 	refill_start = gebase;
362 	if (IS_ENABLED(CONFIG_KVM_MIPS_VZ) && IS_ENABLED(CONFIG_64BIT))
363 		refill_start += 0x080;
364 	refill_end = kvm_mips_build_tlb_refill_exception(refill_start, handler);
365 
366 	/* General Exception Entry point */
367 	kvm_mips_build_exception(gebase + 0x180, handler);
368 
369 	/* For vectored interrupts poke the exception code @ all offsets 0-7 */
370 	for (i = 0; i < 8; i++) {
371 		kvm_debug("L1 Vectored handler @ %p\n",
372 			  gebase + 0x200 + (i * VECTORSPACING));
373 		kvm_mips_build_exception(gebase + 0x200 + i * VECTORSPACING,
374 					 handler);
375 	}
376 
377 	/* General exit handler */
378 	p = handler;
379 	p = kvm_mips_build_exit(p);
380 
381 	/* Guest entry routine */
382 	vcpu->arch.vcpu_run = p;
383 	p = kvm_mips_build_vcpu_run(p);
384 
385 	/* Dump the generated code */
386 	pr_debug("#include <asm/asm.h>\n");
387 	pr_debug("#include <asm/regdef.h>\n");
388 	pr_debug("\n");
389 	dump_handler("kvm_vcpu_run", vcpu->arch.vcpu_run, p);
390 	dump_handler("kvm_tlb_refill", refill_start, refill_end);
391 	dump_handler("kvm_gen_exc", gebase + 0x180, gebase + 0x200);
392 	dump_handler("kvm_exit", gebase + 0x2000, vcpu->arch.vcpu_run);
393 
394 	/* Invalidate the icache for these ranges */
395 	flush_icache_range((unsigned long)gebase,
396 			   (unsigned long)gebase + ALIGN(size, PAGE_SIZE));
397 
398 	/*
399 	 * Allocate comm page for guest kernel, a TLB will be reserved for
400 	 * mapping GVA @ 0xFFFF8000 to this page
401 	 */
402 	vcpu->arch.kseg0_commpage = kzalloc(PAGE_SIZE << 1, GFP_KERNEL);
403 
404 	if (!vcpu->arch.kseg0_commpage) {
405 		err = -ENOMEM;
406 		goto out_free_gebase;
407 	}
408 
409 	kvm_debug("Allocated COMM page @ %p\n", vcpu->arch.kseg0_commpage);
410 	kvm_mips_commpage_init(vcpu);
411 
412 	/* Init */
413 	vcpu->arch.last_sched_cpu = -1;
414 	vcpu->arch.last_exec_cpu = -1;
415 
416 	/* Initial guest state */
417 	err = kvm_mips_callbacks->vcpu_setup(vcpu);
418 	if (err)
419 		goto out_free_commpage;
420 
421 	return 0;
422 
423 out_free_commpage:
424 	kfree(vcpu->arch.kseg0_commpage);
425 out_free_gebase:
426 	kfree(gebase);
427 out_uninit_vcpu:
428 	kvm_mips_callbacks->vcpu_uninit(vcpu);
429 	return err;
430 }
431 
432 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
433 {
434 	hrtimer_cancel(&vcpu->arch.comparecount_timer);
435 
436 	kvm_mips_dump_stats(vcpu);
437 
438 	kvm_mmu_free_memory_caches(vcpu);
439 	kfree(vcpu->arch.guest_ebase);
440 	kfree(vcpu->arch.kseg0_commpage);
441 
442 	kvm_mips_callbacks->vcpu_uninit(vcpu);
443 }
444 
445 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
446 					struct kvm_guest_debug *dbg)
447 {
448 	return -ENOIOCTLCMD;
449 }
450 
451 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
452 {
453 	struct kvm_run *run = vcpu->run;
454 	int r = -EINTR;
455 
456 	vcpu_load(vcpu);
457 
458 	kvm_sigset_activate(vcpu);
459 
460 	if (vcpu->mmio_needed) {
461 		if (!vcpu->mmio_is_write)
462 			kvm_mips_complete_mmio_load(vcpu, run);
463 		vcpu->mmio_needed = 0;
464 	}
465 
466 	if (run->immediate_exit)
467 		goto out;
468 
469 	lose_fpu(1);
470 
471 	local_irq_disable();
472 	guest_enter_irqoff();
473 	trace_kvm_enter(vcpu);
474 
475 	/*
476 	 * Make sure the read of VCPU requests in vcpu_run() callback is not
477 	 * reordered ahead of the write to vcpu->mode, or we could miss a TLB
478 	 * flush request while the requester sees the VCPU as outside of guest
479 	 * mode and not needing an IPI.
480 	 */
481 	smp_store_mb(vcpu->mode, IN_GUEST_MODE);
482 
483 	r = kvm_mips_callbacks->vcpu_run(run, vcpu);
484 
485 	trace_kvm_out(vcpu);
486 	guest_exit_irqoff();
487 	local_irq_enable();
488 
489 out:
490 	kvm_sigset_deactivate(vcpu);
491 
492 	vcpu_put(vcpu);
493 	return r;
494 }
495 
496 int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
497 			     struct kvm_mips_interrupt *irq)
498 {
499 	int intr = (int)irq->irq;
500 	struct kvm_vcpu *dvcpu = NULL;
501 
502 	if (intr == kvm_priority_to_irq[MIPS_EXC_INT_IPI_1] ||
503 	    intr == kvm_priority_to_irq[MIPS_EXC_INT_IPI_2] ||
504 	    intr == (-kvm_priority_to_irq[MIPS_EXC_INT_IPI_1]) ||
505 	    intr == (-kvm_priority_to_irq[MIPS_EXC_INT_IPI_2]))
506 		kvm_debug("%s: CPU: %d, INTR: %d\n", __func__, irq->cpu,
507 			  (int)intr);
508 
509 	if (irq->cpu == -1)
510 		dvcpu = vcpu;
511 	else
512 		dvcpu = vcpu->kvm->vcpus[irq->cpu];
513 
514 	if (intr == 2 || intr == 3 || intr == 4 || intr == 6) {
515 		kvm_mips_callbacks->queue_io_int(dvcpu, irq);
516 
517 	} else if (intr == -2 || intr == -3 || intr == -4 || intr == -6) {
518 		kvm_mips_callbacks->dequeue_io_int(dvcpu, irq);
519 	} else {
520 		kvm_err("%s: invalid interrupt ioctl (%d:%d)\n", __func__,
521 			irq->cpu, irq->irq);
522 		return -EINVAL;
523 	}
524 
525 	dvcpu->arch.wait = 0;
526 
527 	rcuwait_wake_up(&dvcpu->wait);
528 
529 	return 0;
530 }
531 
532 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
533 				    struct kvm_mp_state *mp_state)
534 {
535 	return -ENOIOCTLCMD;
536 }
537 
538 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
539 				    struct kvm_mp_state *mp_state)
540 {
541 	return -ENOIOCTLCMD;
542 }
543 
544 static u64 kvm_mips_get_one_regs[] = {
545 	KVM_REG_MIPS_R0,
546 	KVM_REG_MIPS_R1,
547 	KVM_REG_MIPS_R2,
548 	KVM_REG_MIPS_R3,
549 	KVM_REG_MIPS_R4,
550 	KVM_REG_MIPS_R5,
551 	KVM_REG_MIPS_R6,
552 	KVM_REG_MIPS_R7,
553 	KVM_REG_MIPS_R8,
554 	KVM_REG_MIPS_R9,
555 	KVM_REG_MIPS_R10,
556 	KVM_REG_MIPS_R11,
557 	KVM_REG_MIPS_R12,
558 	KVM_REG_MIPS_R13,
559 	KVM_REG_MIPS_R14,
560 	KVM_REG_MIPS_R15,
561 	KVM_REG_MIPS_R16,
562 	KVM_REG_MIPS_R17,
563 	KVM_REG_MIPS_R18,
564 	KVM_REG_MIPS_R19,
565 	KVM_REG_MIPS_R20,
566 	KVM_REG_MIPS_R21,
567 	KVM_REG_MIPS_R22,
568 	KVM_REG_MIPS_R23,
569 	KVM_REG_MIPS_R24,
570 	KVM_REG_MIPS_R25,
571 	KVM_REG_MIPS_R26,
572 	KVM_REG_MIPS_R27,
573 	KVM_REG_MIPS_R28,
574 	KVM_REG_MIPS_R29,
575 	KVM_REG_MIPS_R30,
576 	KVM_REG_MIPS_R31,
577 
578 #ifndef CONFIG_CPU_MIPSR6
579 	KVM_REG_MIPS_HI,
580 	KVM_REG_MIPS_LO,
581 #endif
582 	KVM_REG_MIPS_PC,
583 };
584 
585 static u64 kvm_mips_get_one_regs_fpu[] = {
586 	KVM_REG_MIPS_FCR_IR,
587 	KVM_REG_MIPS_FCR_CSR,
588 };
589 
590 static u64 kvm_mips_get_one_regs_msa[] = {
591 	KVM_REG_MIPS_MSA_IR,
592 	KVM_REG_MIPS_MSA_CSR,
593 };
594 
595 static unsigned long kvm_mips_num_regs(struct kvm_vcpu *vcpu)
596 {
597 	unsigned long ret;
598 
599 	ret = ARRAY_SIZE(kvm_mips_get_one_regs);
600 	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
601 		ret += ARRAY_SIZE(kvm_mips_get_one_regs_fpu) + 48;
602 		/* odd doubles */
603 		if (boot_cpu_data.fpu_id & MIPS_FPIR_F64)
604 			ret += 16;
605 	}
606 	if (kvm_mips_guest_can_have_msa(&vcpu->arch))
607 		ret += ARRAY_SIZE(kvm_mips_get_one_regs_msa) + 32;
608 	ret += kvm_mips_callbacks->num_regs(vcpu);
609 
610 	return ret;
611 }
612 
613 static int kvm_mips_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices)
614 {
615 	u64 index;
616 	unsigned int i;
617 
618 	if (copy_to_user(indices, kvm_mips_get_one_regs,
619 			 sizeof(kvm_mips_get_one_regs)))
620 		return -EFAULT;
621 	indices += ARRAY_SIZE(kvm_mips_get_one_regs);
622 
623 	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
624 		if (copy_to_user(indices, kvm_mips_get_one_regs_fpu,
625 				 sizeof(kvm_mips_get_one_regs_fpu)))
626 			return -EFAULT;
627 		indices += ARRAY_SIZE(kvm_mips_get_one_regs_fpu);
628 
629 		for (i = 0; i < 32; ++i) {
630 			index = KVM_REG_MIPS_FPR_32(i);
631 			if (copy_to_user(indices, &index, sizeof(index)))
632 				return -EFAULT;
633 			++indices;
634 
635 			/* skip odd doubles if no F64 */
636 			if (i & 1 && !(boot_cpu_data.fpu_id & MIPS_FPIR_F64))
637 				continue;
638 
639 			index = KVM_REG_MIPS_FPR_64(i);
640 			if (copy_to_user(indices, &index, sizeof(index)))
641 				return -EFAULT;
642 			++indices;
643 		}
644 	}
645 
646 	if (kvm_mips_guest_can_have_msa(&vcpu->arch)) {
647 		if (copy_to_user(indices, kvm_mips_get_one_regs_msa,
648 				 sizeof(kvm_mips_get_one_regs_msa)))
649 			return -EFAULT;
650 		indices += ARRAY_SIZE(kvm_mips_get_one_regs_msa);
651 
652 		for (i = 0; i < 32; ++i) {
653 			index = KVM_REG_MIPS_VEC_128(i);
654 			if (copy_to_user(indices, &index, sizeof(index)))
655 				return -EFAULT;
656 			++indices;
657 		}
658 	}
659 
660 	return kvm_mips_callbacks->copy_reg_indices(vcpu, indices);
661 }
662 
663 static int kvm_mips_get_reg(struct kvm_vcpu *vcpu,
664 			    const struct kvm_one_reg *reg)
665 {
666 	struct mips_coproc *cop0 = vcpu->arch.cop0;
667 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
668 	int ret;
669 	s64 v;
670 	s64 vs[2];
671 	unsigned int idx;
672 
673 	switch (reg->id) {
674 	/* General purpose registers */
675 	case KVM_REG_MIPS_R0 ... KVM_REG_MIPS_R31:
676 		v = (long)vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0];
677 		break;
678 #ifndef CONFIG_CPU_MIPSR6
679 	case KVM_REG_MIPS_HI:
680 		v = (long)vcpu->arch.hi;
681 		break;
682 	case KVM_REG_MIPS_LO:
683 		v = (long)vcpu->arch.lo;
684 		break;
685 #endif
686 	case KVM_REG_MIPS_PC:
687 		v = (long)vcpu->arch.pc;
688 		break;
689 
690 	/* Floating point registers */
691 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
692 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
693 			return -EINVAL;
694 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
695 		/* Odd singles in top of even double when FR=0 */
696 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
697 			v = get_fpr32(&fpu->fpr[idx], 0);
698 		else
699 			v = get_fpr32(&fpu->fpr[idx & ~1], idx & 1);
700 		break;
701 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
702 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
703 			return -EINVAL;
704 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
705 		/* Can't access odd doubles in FR=0 mode */
706 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
707 			return -EINVAL;
708 		v = get_fpr64(&fpu->fpr[idx], 0);
709 		break;
710 	case KVM_REG_MIPS_FCR_IR:
711 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
712 			return -EINVAL;
713 		v = boot_cpu_data.fpu_id;
714 		break;
715 	case KVM_REG_MIPS_FCR_CSR:
716 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
717 			return -EINVAL;
718 		v = fpu->fcr31;
719 		break;
720 
721 	/* MIPS SIMD Architecture (MSA) registers */
722 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
723 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
724 			return -EINVAL;
725 		/* Can't access MSA registers in FR=0 mode */
726 		if (!(kvm_read_c0_guest_status(cop0) & ST0_FR))
727 			return -EINVAL;
728 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
729 #ifdef CONFIG_CPU_LITTLE_ENDIAN
730 		/* least significant byte first */
731 		vs[0] = get_fpr64(&fpu->fpr[idx], 0);
732 		vs[1] = get_fpr64(&fpu->fpr[idx], 1);
733 #else
734 		/* most significant byte first */
735 		vs[0] = get_fpr64(&fpu->fpr[idx], 1);
736 		vs[1] = get_fpr64(&fpu->fpr[idx], 0);
737 #endif
738 		break;
739 	case KVM_REG_MIPS_MSA_IR:
740 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
741 			return -EINVAL;
742 		v = boot_cpu_data.msa_id;
743 		break;
744 	case KVM_REG_MIPS_MSA_CSR:
745 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
746 			return -EINVAL;
747 		v = fpu->msacsr;
748 		break;
749 
750 	/* registers to be handled specially */
751 	default:
752 		ret = kvm_mips_callbacks->get_one_reg(vcpu, reg, &v);
753 		if (ret)
754 			return ret;
755 		break;
756 	}
757 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
758 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
759 
760 		return put_user(v, uaddr64);
761 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
762 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
763 		u32 v32 = (u32)v;
764 
765 		return put_user(v32, uaddr32);
766 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
767 		void __user *uaddr = (void __user *)(long)reg->addr;
768 
769 		return copy_to_user(uaddr, vs, 16) ? -EFAULT : 0;
770 	} else {
771 		return -EINVAL;
772 	}
773 }
774 
775 static int kvm_mips_set_reg(struct kvm_vcpu *vcpu,
776 			    const struct kvm_one_reg *reg)
777 {
778 	struct mips_coproc *cop0 = vcpu->arch.cop0;
779 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
780 	s64 v;
781 	s64 vs[2];
782 	unsigned int idx;
783 
784 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
785 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
786 
787 		if (get_user(v, uaddr64) != 0)
788 			return -EFAULT;
789 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
790 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
791 		s32 v32;
792 
793 		if (get_user(v32, uaddr32) != 0)
794 			return -EFAULT;
795 		v = (s64)v32;
796 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
797 		void __user *uaddr = (void __user *)(long)reg->addr;
798 
799 		return copy_from_user(vs, uaddr, 16) ? -EFAULT : 0;
800 	} else {
801 		return -EINVAL;
802 	}
803 
804 	switch (reg->id) {
805 	/* General purpose registers */
806 	case KVM_REG_MIPS_R0:
807 		/* Silently ignore requests to set $0 */
808 		break;
809 	case KVM_REG_MIPS_R1 ... KVM_REG_MIPS_R31:
810 		vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0] = v;
811 		break;
812 #ifndef CONFIG_CPU_MIPSR6
813 	case KVM_REG_MIPS_HI:
814 		vcpu->arch.hi = v;
815 		break;
816 	case KVM_REG_MIPS_LO:
817 		vcpu->arch.lo = v;
818 		break;
819 #endif
820 	case KVM_REG_MIPS_PC:
821 		vcpu->arch.pc = v;
822 		break;
823 
824 	/* Floating point registers */
825 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
826 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
827 			return -EINVAL;
828 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
829 		/* Odd singles in top of even double when FR=0 */
830 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
831 			set_fpr32(&fpu->fpr[idx], 0, v);
832 		else
833 			set_fpr32(&fpu->fpr[idx & ~1], idx & 1, v);
834 		break;
835 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
836 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
837 			return -EINVAL;
838 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
839 		/* Can't access odd doubles in FR=0 mode */
840 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
841 			return -EINVAL;
842 		set_fpr64(&fpu->fpr[idx], 0, v);
843 		break;
844 	case KVM_REG_MIPS_FCR_IR:
845 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
846 			return -EINVAL;
847 		/* Read-only */
848 		break;
849 	case KVM_REG_MIPS_FCR_CSR:
850 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
851 			return -EINVAL;
852 		fpu->fcr31 = v;
853 		break;
854 
855 	/* MIPS SIMD Architecture (MSA) registers */
856 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
857 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
858 			return -EINVAL;
859 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
860 #ifdef CONFIG_CPU_LITTLE_ENDIAN
861 		/* least significant byte first */
862 		set_fpr64(&fpu->fpr[idx], 0, vs[0]);
863 		set_fpr64(&fpu->fpr[idx], 1, vs[1]);
864 #else
865 		/* most significant byte first */
866 		set_fpr64(&fpu->fpr[idx], 1, vs[0]);
867 		set_fpr64(&fpu->fpr[idx], 0, vs[1]);
868 #endif
869 		break;
870 	case KVM_REG_MIPS_MSA_IR:
871 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
872 			return -EINVAL;
873 		/* Read-only */
874 		break;
875 	case KVM_REG_MIPS_MSA_CSR:
876 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
877 			return -EINVAL;
878 		fpu->msacsr = v;
879 		break;
880 
881 	/* registers to be handled specially */
882 	default:
883 		return kvm_mips_callbacks->set_one_reg(vcpu, reg, v);
884 	}
885 	return 0;
886 }
887 
888 static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
889 				     struct kvm_enable_cap *cap)
890 {
891 	int r = 0;
892 
893 	if (!kvm_vm_ioctl_check_extension(vcpu->kvm, cap->cap))
894 		return -EINVAL;
895 	if (cap->flags)
896 		return -EINVAL;
897 	if (cap->args[0])
898 		return -EINVAL;
899 
900 	switch (cap->cap) {
901 	case KVM_CAP_MIPS_FPU:
902 		vcpu->arch.fpu_enabled = true;
903 		break;
904 	case KVM_CAP_MIPS_MSA:
905 		vcpu->arch.msa_enabled = true;
906 		break;
907 	default:
908 		r = -EINVAL;
909 		break;
910 	}
911 
912 	return r;
913 }
914 
915 long kvm_arch_vcpu_async_ioctl(struct file *filp, unsigned int ioctl,
916 			       unsigned long arg)
917 {
918 	struct kvm_vcpu *vcpu = filp->private_data;
919 	void __user *argp = (void __user *)arg;
920 
921 	if (ioctl == KVM_INTERRUPT) {
922 		struct kvm_mips_interrupt irq;
923 
924 		if (copy_from_user(&irq, argp, sizeof(irq)))
925 			return -EFAULT;
926 		kvm_debug("[%d] %s: irq: %d\n", vcpu->vcpu_id, __func__,
927 			  irq.irq);
928 
929 		return kvm_vcpu_ioctl_interrupt(vcpu, &irq);
930 	}
931 
932 	return -ENOIOCTLCMD;
933 }
934 
935 long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl,
936 			 unsigned long arg)
937 {
938 	struct kvm_vcpu *vcpu = filp->private_data;
939 	void __user *argp = (void __user *)arg;
940 	long r;
941 
942 	vcpu_load(vcpu);
943 
944 	switch (ioctl) {
945 	case KVM_SET_ONE_REG:
946 	case KVM_GET_ONE_REG: {
947 		struct kvm_one_reg reg;
948 
949 		r = -EFAULT;
950 		if (copy_from_user(&reg, argp, sizeof(reg)))
951 			break;
952 		if (ioctl == KVM_SET_ONE_REG)
953 			r = kvm_mips_set_reg(vcpu, &reg);
954 		else
955 			r = kvm_mips_get_reg(vcpu, &reg);
956 		break;
957 	}
958 	case KVM_GET_REG_LIST: {
959 		struct kvm_reg_list __user *user_list = argp;
960 		struct kvm_reg_list reg_list;
961 		unsigned n;
962 
963 		r = -EFAULT;
964 		if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
965 			break;
966 		n = reg_list.n;
967 		reg_list.n = kvm_mips_num_regs(vcpu);
968 		if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
969 			break;
970 		r = -E2BIG;
971 		if (n < reg_list.n)
972 			break;
973 		r = kvm_mips_copy_reg_indices(vcpu, user_list->reg);
974 		break;
975 	}
976 	case KVM_ENABLE_CAP: {
977 		struct kvm_enable_cap cap;
978 
979 		r = -EFAULT;
980 		if (copy_from_user(&cap, argp, sizeof(cap)))
981 			break;
982 		r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
983 		break;
984 	}
985 	default:
986 		r = -ENOIOCTLCMD;
987 	}
988 
989 	vcpu_put(vcpu);
990 	return r;
991 }
992 
993 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
994 {
995 
996 }
997 
998 void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
999 					struct kvm_memory_slot *memslot)
1000 {
1001 	/* Let implementation handle TLB/GVA invalidation */
1002 	kvm_mips_callbacks->flush_shadow_memslot(kvm, memslot);
1003 }
1004 
1005 long kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
1006 {
1007 	long r;
1008 
1009 	switch (ioctl) {
1010 	default:
1011 		r = -ENOIOCTLCMD;
1012 	}
1013 
1014 	return r;
1015 }
1016 
1017 int kvm_arch_init(void *opaque)
1018 {
1019 	if (kvm_mips_callbacks) {
1020 		kvm_err("kvm: module already exists\n");
1021 		return -EEXIST;
1022 	}
1023 
1024 	return kvm_mips_emulation_init(&kvm_mips_callbacks);
1025 }
1026 
1027 void kvm_arch_exit(void)
1028 {
1029 	kvm_mips_callbacks = NULL;
1030 }
1031 
1032 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
1033 				  struct kvm_sregs *sregs)
1034 {
1035 	return -ENOIOCTLCMD;
1036 }
1037 
1038 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
1039 				  struct kvm_sregs *sregs)
1040 {
1041 	return -ENOIOCTLCMD;
1042 }
1043 
1044 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
1045 {
1046 }
1047 
1048 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1049 {
1050 	return -ENOIOCTLCMD;
1051 }
1052 
1053 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1054 {
1055 	return -ENOIOCTLCMD;
1056 }
1057 
1058 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
1059 {
1060 	return VM_FAULT_SIGBUS;
1061 }
1062 
1063 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
1064 {
1065 	int r;
1066 
1067 	switch (ext) {
1068 	case KVM_CAP_ONE_REG:
1069 	case KVM_CAP_ENABLE_CAP:
1070 	case KVM_CAP_READONLY_MEM:
1071 	case KVM_CAP_SYNC_MMU:
1072 	case KVM_CAP_IMMEDIATE_EXIT:
1073 		r = 1;
1074 		break;
1075 	case KVM_CAP_NR_VCPUS:
1076 		r = num_online_cpus();
1077 		break;
1078 	case KVM_CAP_MAX_VCPUS:
1079 		r = KVM_MAX_VCPUS;
1080 		break;
1081 	case KVM_CAP_MAX_VCPU_ID:
1082 		r = KVM_MAX_VCPU_ID;
1083 		break;
1084 	case KVM_CAP_MIPS_FPU:
1085 		/* We don't handle systems with inconsistent cpu_has_fpu */
1086 		r = !!raw_cpu_has_fpu;
1087 		break;
1088 	case KVM_CAP_MIPS_MSA:
1089 		/*
1090 		 * We don't support MSA vector partitioning yet:
1091 		 * 1) It would require explicit support which can't be tested
1092 		 *    yet due to lack of support in current hardware.
1093 		 * 2) It extends the state that would need to be saved/restored
1094 		 *    by e.g. QEMU for migration.
1095 		 *
1096 		 * When vector partitioning hardware becomes available, support
1097 		 * could be added by requiring a flag when enabling
1098 		 * KVM_CAP_MIPS_MSA capability to indicate that userland knows
1099 		 * to save/restore the appropriate extra state.
1100 		 */
1101 		r = cpu_has_msa && !(boot_cpu_data.msa_id & MSA_IR_WRPF);
1102 		break;
1103 	default:
1104 		r = kvm_mips_callbacks->check_extension(kvm, ext);
1105 		break;
1106 	}
1107 	return r;
1108 }
1109 
1110 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
1111 {
1112 	return kvm_mips_pending_timer(vcpu) ||
1113 		kvm_read_c0_guest_cause(vcpu->arch.cop0) & C_TI;
1114 }
1115 
1116 int kvm_arch_vcpu_dump_regs(struct kvm_vcpu *vcpu)
1117 {
1118 	int i;
1119 	struct mips_coproc *cop0;
1120 
1121 	if (!vcpu)
1122 		return -1;
1123 
1124 	kvm_debug("VCPU Register Dump:\n");
1125 	kvm_debug("\tpc = 0x%08lx\n", vcpu->arch.pc);
1126 	kvm_debug("\texceptions: %08lx\n", vcpu->arch.pending_exceptions);
1127 
1128 	for (i = 0; i < 32; i += 4) {
1129 		kvm_debug("\tgpr%02d: %08lx %08lx %08lx %08lx\n", i,
1130 		       vcpu->arch.gprs[i],
1131 		       vcpu->arch.gprs[i + 1],
1132 		       vcpu->arch.gprs[i + 2], vcpu->arch.gprs[i + 3]);
1133 	}
1134 	kvm_debug("\thi: 0x%08lx\n", vcpu->arch.hi);
1135 	kvm_debug("\tlo: 0x%08lx\n", vcpu->arch.lo);
1136 
1137 	cop0 = vcpu->arch.cop0;
1138 	kvm_debug("\tStatus: 0x%08x, Cause: 0x%08x\n",
1139 		  kvm_read_c0_guest_status(cop0),
1140 		  kvm_read_c0_guest_cause(cop0));
1141 
1142 	kvm_debug("\tEPC: 0x%08lx\n", kvm_read_c0_guest_epc(cop0));
1143 
1144 	return 0;
1145 }
1146 
1147 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1148 {
1149 	int i;
1150 
1151 	vcpu_load(vcpu);
1152 
1153 	for (i = 1; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1154 		vcpu->arch.gprs[i] = regs->gpr[i];
1155 	vcpu->arch.gprs[0] = 0; /* zero is special, and cannot be set. */
1156 	vcpu->arch.hi = regs->hi;
1157 	vcpu->arch.lo = regs->lo;
1158 	vcpu->arch.pc = regs->pc;
1159 
1160 	vcpu_put(vcpu);
1161 	return 0;
1162 }
1163 
1164 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1165 {
1166 	int i;
1167 
1168 	vcpu_load(vcpu);
1169 
1170 	for (i = 0; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1171 		regs->gpr[i] = vcpu->arch.gprs[i];
1172 
1173 	regs->hi = vcpu->arch.hi;
1174 	regs->lo = vcpu->arch.lo;
1175 	regs->pc = vcpu->arch.pc;
1176 
1177 	vcpu_put(vcpu);
1178 	return 0;
1179 }
1180 
1181 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
1182 				  struct kvm_translation *tr)
1183 {
1184 	return 0;
1185 }
1186 
1187 static void kvm_mips_set_c0_status(void)
1188 {
1189 	u32 status = read_c0_status();
1190 
1191 	if (cpu_has_dsp)
1192 		status |= (ST0_MX);
1193 
1194 	write_c0_status(status);
1195 	ehb();
1196 }
1197 
1198 /*
1199  * Return value is in the form (errcode<<2 | RESUME_FLAG_HOST | RESUME_FLAG_NV)
1200  */
1201 int kvm_mips_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu)
1202 {
1203 	u32 cause = vcpu->arch.host_cp0_cause;
1204 	u32 exccode = (cause >> CAUSEB_EXCCODE) & 0x1f;
1205 	u32 __user *opc = (u32 __user *) vcpu->arch.pc;
1206 	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
1207 	enum emulation_result er = EMULATE_DONE;
1208 	u32 inst;
1209 	int ret = RESUME_GUEST;
1210 
1211 	vcpu->mode = OUTSIDE_GUEST_MODE;
1212 
1213 	/* re-enable HTW before enabling interrupts */
1214 	if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ))
1215 		htw_start();
1216 
1217 	/* Set a default exit reason */
1218 	run->exit_reason = KVM_EXIT_UNKNOWN;
1219 	run->ready_for_interrupt_injection = 1;
1220 
1221 	/*
1222 	 * Set the appropriate status bits based on host CPU features,
1223 	 * before we hit the scheduler
1224 	 */
1225 	kvm_mips_set_c0_status();
1226 
1227 	local_irq_enable();
1228 
1229 	kvm_debug("kvm_mips_handle_exit: cause: %#x, PC: %p, kvm_run: %p, kvm_vcpu: %p\n",
1230 			cause, opc, run, vcpu);
1231 	trace_kvm_exit(vcpu, exccode);
1232 
1233 	if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) {
1234 		/*
1235 		 * Do a privilege check, if in UM most of these exit conditions
1236 		 * end up causing an exception to be delivered to the Guest
1237 		 * Kernel
1238 		 */
1239 		er = kvm_mips_check_privilege(cause, opc, run, vcpu);
1240 		if (er == EMULATE_PRIV_FAIL) {
1241 			goto skip_emul;
1242 		} else if (er == EMULATE_FAIL) {
1243 			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1244 			ret = RESUME_HOST;
1245 			goto skip_emul;
1246 		}
1247 	}
1248 
1249 	switch (exccode) {
1250 	case EXCCODE_INT:
1251 		kvm_debug("[%d]EXCCODE_INT @ %p\n", vcpu->vcpu_id, opc);
1252 
1253 		++vcpu->stat.int_exits;
1254 
1255 		if (need_resched())
1256 			cond_resched();
1257 
1258 		ret = RESUME_GUEST;
1259 		break;
1260 
1261 	case EXCCODE_CPU:
1262 		kvm_debug("EXCCODE_CPU: @ PC: %p\n", opc);
1263 
1264 		++vcpu->stat.cop_unusable_exits;
1265 		ret = kvm_mips_callbacks->handle_cop_unusable(vcpu);
1266 		/* XXXKYMA: Might need to return to user space */
1267 		if (run->exit_reason == KVM_EXIT_IRQ_WINDOW_OPEN)
1268 			ret = RESUME_HOST;
1269 		break;
1270 
1271 	case EXCCODE_MOD:
1272 		++vcpu->stat.tlbmod_exits;
1273 		ret = kvm_mips_callbacks->handle_tlb_mod(vcpu);
1274 		break;
1275 
1276 	case EXCCODE_TLBS:
1277 		kvm_debug("TLB ST fault:  cause %#x, status %#x, PC: %p, BadVaddr: %#lx\n",
1278 			  cause, kvm_read_c0_guest_status(vcpu->arch.cop0), opc,
1279 			  badvaddr);
1280 
1281 		++vcpu->stat.tlbmiss_st_exits;
1282 		ret = kvm_mips_callbacks->handle_tlb_st_miss(vcpu);
1283 		break;
1284 
1285 	case EXCCODE_TLBL:
1286 		kvm_debug("TLB LD fault: cause %#x, PC: %p, BadVaddr: %#lx\n",
1287 			  cause, opc, badvaddr);
1288 
1289 		++vcpu->stat.tlbmiss_ld_exits;
1290 		ret = kvm_mips_callbacks->handle_tlb_ld_miss(vcpu);
1291 		break;
1292 
1293 	case EXCCODE_ADES:
1294 		++vcpu->stat.addrerr_st_exits;
1295 		ret = kvm_mips_callbacks->handle_addr_err_st(vcpu);
1296 		break;
1297 
1298 	case EXCCODE_ADEL:
1299 		++vcpu->stat.addrerr_ld_exits;
1300 		ret = kvm_mips_callbacks->handle_addr_err_ld(vcpu);
1301 		break;
1302 
1303 	case EXCCODE_SYS:
1304 		++vcpu->stat.syscall_exits;
1305 		ret = kvm_mips_callbacks->handle_syscall(vcpu);
1306 		break;
1307 
1308 	case EXCCODE_RI:
1309 		++vcpu->stat.resvd_inst_exits;
1310 		ret = kvm_mips_callbacks->handle_res_inst(vcpu);
1311 		break;
1312 
1313 	case EXCCODE_BP:
1314 		++vcpu->stat.break_inst_exits;
1315 		ret = kvm_mips_callbacks->handle_break(vcpu);
1316 		break;
1317 
1318 	case EXCCODE_TR:
1319 		++vcpu->stat.trap_inst_exits;
1320 		ret = kvm_mips_callbacks->handle_trap(vcpu);
1321 		break;
1322 
1323 	case EXCCODE_MSAFPE:
1324 		++vcpu->stat.msa_fpe_exits;
1325 		ret = kvm_mips_callbacks->handle_msa_fpe(vcpu);
1326 		break;
1327 
1328 	case EXCCODE_FPE:
1329 		++vcpu->stat.fpe_exits;
1330 		ret = kvm_mips_callbacks->handle_fpe(vcpu);
1331 		break;
1332 
1333 	case EXCCODE_MSADIS:
1334 		++vcpu->stat.msa_disabled_exits;
1335 		ret = kvm_mips_callbacks->handle_msa_disabled(vcpu);
1336 		break;
1337 
1338 	case EXCCODE_GE:
1339 		/* defer exit accounting to handler */
1340 		ret = kvm_mips_callbacks->handle_guest_exit(vcpu);
1341 		break;
1342 
1343 	default:
1344 		if (cause & CAUSEF_BD)
1345 			opc += 1;
1346 		inst = 0;
1347 		kvm_get_badinstr(opc, vcpu, &inst);
1348 		kvm_err("Exception Code: %d, not yet handled, @ PC: %p, inst: 0x%08x  BadVaddr: %#lx Status: %#x\n",
1349 			exccode, opc, inst, badvaddr,
1350 			kvm_read_c0_guest_status(vcpu->arch.cop0));
1351 		kvm_arch_vcpu_dump_regs(vcpu);
1352 		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1353 		ret = RESUME_HOST;
1354 		break;
1355 
1356 	}
1357 
1358 skip_emul:
1359 	local_irq_disable();
1360 
1361 	if (ret == RESUME_GUEST)
1362 		kvm_vz_acquire_htimer(vcpu);
1363 
1364 	if (er == EMULATE_DONE && !(ret & RESUME_HOST))
1365 		kvm_mips_deliver_interrupts(vcpu, cause);
1366 
1367 	if (!(ret & RESUME_HOST)) {
1368 		/* Only check for signals if not already exiting to userspace */
1369 		if (signal_pending(current)) {
1370 			run->exit_reason = KVM_EXIT_INTR;
1371 			ret = (-EINTR << 2) | RESUME_HOST;
1372 			++vcpu->stat.signal_exits;
1373 			trace_kvm_exit(vcpu, KVM_TRACE_EXIT_SIGNAL);
1374 		}
1375 	}
1376 
1377 	if (ret == RESUME_GUEST) {
1378 		trace_kvm_reenter(vcpu);
1379 
1380 		/*
1381 		 * Make sure the read of VCPU requests in vcpu_reenter()
1382 		 * callback is not reordered ahead of the write to vcpu->mode,
1383 		 * or we could miss a TLB flush request while the requester sees
1384 		 * the VCPU as outside of guest mode and not needing an IPI.
1385 		 */
1386 		smp_store_mb(vcpu->mode, IN_GUEST_MODE);
1387 
1388 		kvm_mips_callbacks->vcpu_reenter(run, vcpu);
1389 
1390 		/*
1391 		 * If FPU / MSA are enabled (i.e. the guest's FPU / MSA context
1392 		 * is live), restore FCR31 / MSACSR.
1393 		 *
1394 		 * This should be before returning to the guest exception
1395 		 * vector, as it may well cause an [MSA] FP exception if there
1396 		 * are pending exception bits unmasked. (see
1397 		 * kvm_mips_csr_die_notifier() for how that is handled).
1398 		 */
1399 		if (kvm_mips_guest_has_fpu(&vcpu->arch) &&
1400 		    read_c0_status() & ST0_CU1)
1401 			__kvm_restore_fcsr(&vcpu->arch);
1402 
1403 		if (kvm_mips_guest_has_msa(&vcpu->arch) &&
1404 		    read_c0_config5() & MIPS_CONF5_MSAEN)
1405 			__kvm_restore_msacsr(&vcpu->arch);
1406 	}
1407 
1408 	/* Disable HTW before returning to guest or host */
1409 	if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ))
1410 		htw_stop();
1411 
1412 	return ret;
1413 }
1414 
1415 /* Enable FPU for guest and restore context */
1416 void kvm_own_fpu(struct kvm_vcpu *vcpu)
1417 {
1418 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1419 	unsigned int sr, cfg5;
1420 
1421 	preempt_disable();
1422 
1423 	sr = kvm_read_c0_guest_status(cop0);
1424 
1425 	/*
1426 	 * If MSA state is already live, it is undefined how it interacts with
1427 	 * FR=0 FPU state, and we don't want to hit reserved instruction
1428 	 * exceptions trying to save the MSA state later when CU=1 && FR=1, so
1429 	 * play it safe and save it first.
1430 	 *
1431 	 * In theory we shouldn't ever hit this case since kvm_lose_fpu() should
1432 	 * get called when guest CU1 is set, however we can't trust the guest
1433 	 * not to clobber the status register directly via the commpage.
1434 	 */
1435 	if (cpu_has_msa && sr & ST0_CU1 && !(sr & ST0_FR) &&
1436 	    vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA)
1437 		kvm_lose_fpu(vcpu);
1438 
1439 	/*
1440 	 * Enable FPU for guest
1441 	 * We set FR and FRE according to guest context
1442 	 */
1443 	change_c0_status(ST0_CU1 | ST0_FR, sr);
1444 	if (cpu_has_fre) {
1445 		cfg5 = kvm_read_c0_guest_config5(cop0);
1446 		change_c0_config5(MIPS_CONF5_FRE, cfg5);
1447 	}
1448 	enable_fpu_hazard();
1449 
1450 	/* If guest FPU state not active, restore it now */
1451 	if (!(vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU)) {
1452 		__kvm_restore_fpu(&vcpu->arch);
1453 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1454 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_FPU);
1455 	} else {
1456 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_FPU);
1457 	}
1458 
1459 	preempt_enable();
1460 }
1461 
1462 #ifdef CONFIG_CPU_HAS_MSA
1463 /* Enable MSA for guest and restore context */
1464 void kvm_own_msa(struct kvm_vcpu *vcpu)
1465 {
1466 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1467 	unsigned int sr, cfg5;
1468 
1469 	preempt_disable();
1470 
1471 	/*
1472 	 * Enable FPU if enabled in guest, since we're restoring FPU context
1473 	 * anyway. We set FR and FRE according to guest context.
1474 	 */
1475 	if (kvm_mips_guest_has_fpu(&vcpu->arch)) {
1476 		sr = kvm_read_c0_guest_status(cop0);
1477 
1478 		/*
1479 		 * If FR=0 FPU state is already live, it is undefined how it
1480 		 * interacts with MSA state, so play it safe and save it first.
1481 		 */
1482 		if (!(sr & ST0_FR) &&
1483 		    (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU |
1484 				KVM_MIPS_AUX_MSA)) == KVM_MIPS_AUX_FPU)
1485 			kvm_lose_fpu(vcpu);
1486 
1487 		change_c0_status(ST0_CU1 | ST0_FR, sr);
1488 		if (sr & ST0_CU1 && cpu_has_fre) {
1489 			cfg5 = kvm_read_c0_guest_config5(cop0);
1490 			change_c0_config5(MIPS_CONF5_FRE, cfg5);
1491 		}
1492 	}
1493 
1494 	/* Enable MSA for guest */
1495 	set_c0_config5(MIPS_CONF5_MSAEN);
1496 	enable_fpu_hazard();
1497 
1498 	switch (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA)) {
1499 	case KVM_MIPS_AUX_FPU:
1500 		/*
1501 		 * Guest FPU state already loaded, only restore upper MSA state
1502 		 */
1503 		__kvm_restore_msa_upper(&vcpu->arch);
1504 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1505 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_MSA);
1506 		break;
1507 	case 0:
1508 		/* Neither FPU or MSA already active, restore full MSA state */
1509 		__kvm_restore_msa(&vcpu->arch);
1510 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1511 		if (kvm_mips_guest_has_fpu(&vcpu->arch))
1512 			vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1513 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE,
1514 			      KVM_TRACE_AUX_FPU_MSA);
1515 		break;
1516 	default:
1517 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_MSA);
1518 		break;
1519 	}
1520 
1521 	preempt_enable();
1522 }
1523 #endif
1524 
1525 /* Drop FPU & MSA without saving it */
1526 void kvm_drop_fpu(struct kvm_vcpu *vcpu)
1527 {
1528 	preempt_disable();
1529 	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1530 		disable_msa();
1531 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_MSA);
1532 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_MSA;
1533 	}
1534 	if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1535 		clear_c0_status(ST0_CU1 | ST0_FR);
1536 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_FPU);
1537 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1538 	}
1539 	preempt_enable();
1540 }
1541 
1542 /* Save and disable FPU & MSA */
1543 void kvm_lose_fpu(struct kvm_vcpu *vcpu)
1544 {
1545 	/*
1546 	 * With T&E, FPU & MSA get disabled in root context (hardware) when it
1547 	 * is disabled in guest context (software), but the register state in
1548 	 * the hardware may still be in use.
1549 	 * This is why we explicitly re-enable the hardware before saving.
1550 	 */
1551 
1552 	preempt_disable();
1553 	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1554 		if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) {
1555 			set_c0_config5(MIPS_CONF5_MSAEN);
1556 			enable_fpu_hazard();
1557 		}
1558 
1559 		__kvm_save_msa(&vcpu->arch);
1560 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU_MSA);
1561 
1562 		/* Disable MSA & FPU */
1563 		disable_msa();
1564 		if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1565 			clear_c0_status(ST0_CU1 | ST0_FR);
1566 			disable_fpu_hazard();
1567 		}
1568 		vcpu->arch.aux_inuse &= ~(KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA);
1569 	} else if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1570 		if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) {
1571 			set_c0_status(ST0_CU1);
1572 			enable_fpu_hazard();
1573 		}
1574 
1575 		__kvm_save_fpu(&vcpu->arch);
1576 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1577 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU);
1578 
1579 		/* Disable FPU */
1580 		clear_c0_status(ST0_CU1 | ST0_FR);
1581 		disable_fpu_hazard();
1582 	}
1583 	preempt_enable();
1584 }
1585 
1586 /*
1587  * Step over a specific ctc1 to FCSR and a specific ctcmsa to MSACSR which are
1588  * used to restore guest FCSR/MSACSR state and may trigger a "harmless" FP/MSAFP
1589  * exception if cause bits are set in the value being written.
1590  */
1591 static int kvm_mips_csr_die_notify(struct notifier_block *self,
1592 				   unsigned long cmd, void *ptr)
1593 {
1594 	struct die_args *args = (struct die_args *)ptr;
1595 	struct pt_regs *regs = args->regs;
1596 	unsigned long pc;
1597 
1598 	/* Only interested in FPE and MSAFPE */
1599 	if (cmd != DIE_FP && cmd != DIE_MSAFP)
1600 		return NOTIFY_DONE;
1601 
1602 	/* Return immediately if guest context isn't active */
1603 	if (!(current->flags & PF_VCPU))
1604 		return NOTIFY_DONE;
1605 
1606 	/* Should never get here from user mode */
1607 	BUG_ON(user_mode(regs));
1608 
1609 	pc = instruction_pointer(regs);
1610 	switch (cmd) {
1611 	case DIE_FP:
1612 		/* match 2nd instruction in __kvm_restore_fcsr */
1613 		if (pc != (unsigned long)&__kvm_restore_fcsr + 4)
1614 			return NOTIFY_DONE;
1615 		break;
1616 	case DIE_MSAFP:
1617 		/* match 2nd/3rd instruction in __kvm_restore_msacsr */
1618 		if (!cpu_has_msa ||
1619 		    pc < (unsigned long)&__kvm_restore_msacsr + 4 ||
1620 		    pc > (unsigned long)&__kvm_restore_msacsr + 8)
1621 			return NOTIFY_DONE;
1622 		break;
1623 	}
1624 
1625 	/* Move PC forward a little and continue executing */
1626 	instruction_pointer(regs) += 4;
1627 
1628 	return NOTIFY_STOP;
1629 }
1630 
1631 static struct notifier_block kvm_mips_csr_die_notifier = {
1632 	.notifier_call = kvm_mips_csr_die_notify,
1633 };
1634 
1635 static u32 kvm_default_priority_to_irq[MIPS_EXC_MAX] = {
1636 	[MIPS_EXC_INT_TIMER] = C_IRQ5,
1637 	[MIPS_EXC_INT_IO_1]  = C_IRQ0,
1638 	[MIPS_EXC_INT_IPI_1] = C_IRQ1,
1639 	[MIPS_EXC_INT_IPI_2] = C_IRQ2,
1640 };
1641 
1642 static u32 kvm_loongson3_priority_to_irq[MIPS_EXC_MAX] = {
1643 	[MIPS_EXC_INT_TIMER] = C_IRQ5,
1644 	[MIPS_EXC_INT_IO_1]  = C_IRQ0,
1645 	[MIPS_EXC_INT_IO_2]  = C_IRQ1,
1646 	[MIPS_EXC_INT_IPI_1] = C_IRQ4,
1647 };
1648 
1649 u32 *kvm_priority_to_irq = kvm_default_priority_to_irq;
1650 
1651 u32 kvm_irq_to_priority(u32 irq)
1652 {
1653 	int i;
1654 
1655 	for (i = MIPS_EXC_INT_TIMER; i < MIPS_EXC_MAX; i++) {
1656 		if (kvm_priority_to_irq[i] == (1 << (irq + 8)))
1657 			return i;
1658 	}
1659 
1660 	return MIPS_EXC_MAX;
1661 }
1662 
1663 static int __init kvm_mips_init(void)
1664 {
1665 	int ret;
1666 
1667 	if (cpu_has_mmid) {
1668 		pr_warn("KVM does not yet support MMIDs. KVM Disabled\n");
1669 		return -EOPNOTSUPP;
1670 	}
1671 
1672 	ret = kvm_mips_entry_setup();
1673 	if (ret)
1674 		return ret;
1675 
1676 	ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
1677 
1678 	if (ret)
1679 		return ret;
1680 
1681 	if (boot_cpu_type() == CPU_LOONGSON64)
1682 		kvm_priority_to_irq = kvm_loongson3_priority_to_irq;
1683 
1684 	register_die_notifier(&kvm_mips_csr_die_notifier);
1685 
1686 	return 0;
1687 }
1688 
1689 static void __exit kvm_mips_exit(void)
1690 {
1691 	kvm_exit();
1692 
1693 	unregister_die_notifier(&kvm_mips_csr_die_notifier);
1694 }
1695 
1696 module_init(kvm_mips_init);
1697 module_exit(kvm_mips_exit);
1698 
1699 EXPORT_TRACEPOINT_SYMBOL(kvm_exit);
1700