xref: /openbmc/linux/arch/mips/kvm/mips.c (revision 8730046c)
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/fs.h>
20 #include <linux/bootmem.h>
21 #include <asm/fpu.h>
22 #include <asm/page.h>
23 #include <asm/cacheflush.h>
24 #include <asm/mmu_context.h>
25 #include <asm/pgtable.h>
26 
27 #include <linux/kvm_host.h>
28 
29 #include "interrupt.h"
30 #include "commpage.h"
31 
32 #define CREATE_TRACE_POINTS
33 #include "trace.h"
34 
35 #ifndef VECTORSPACING
36 #define VECTORSPACING 0x100	/* for EI/VI mode */
37 #endif
38 
39 #define VCPU_STAT(x) offsetof(struct kvm_vcpu, stat.x)
40 struct kvm_stats_debugfs_item debugfs_entries[] = {
41 	{ "wait",	  VCPU_STAT(wait_exits),	 KVM_STAT_VCPU },
42 	{ "cache",	  VCPU_STAT(cache_exits),	 KVM_STAT_VCPU },
43 	{ "signal",	  VCPU_STAT(signal_exits),	 KVM_STAT_VCPU },
44 	{ "interrupt",	  VCPU_STAT(int_exits),		 KVM_STAT_VCPU },
45 	{ "cop_unsuable", VCPU_STAT(cop_unusable_exits), KVM_STAT_VCPU },
46 	{ "tlbmod",	  VCPU_STAT(tlbmod_exits),	 KVM_STAT_VCPU },
47 	{ "tlbmiss_ld",	  VCPU_STAT(tlbmiss_ld_exits),	 KVM_STAT_VCPU },
48 	{ "tlbmiss_st",	  VCPU_STAT(tlbmiss_st_exits),	 KVM_STAT_VCPU },
49 	{ "addrerr_st",	  VCPU_STAT(addrerr_st_exits),	 KVM_STAT_VCPU },
50 	{ "addrerr_ld",	  VCPU_STAT(addrerr_ld_exits),	 KVM_STAT_VCPU },
51 	{ "syscall",	  VCPU_STAT(syscall_exits),	 KVM_STAT_VCPU },
52 	{ "resvd_inst",	  VCPU_STAT(resvd_inst_exits),	 KVM_STAT_VCPU },
53 	{ "break_inst",	  VCPU_STAT(break_inst_exits),	 KVM_STAT_VCPU },
54 	{ "trap_inst",	  VCPU_STAT(trap_inst_exits),	 KVM_STAT_VCPU },
55 	{ "msa_fpe",	  VCPU_STAT(msa_fpe_exits),	 KVM_STAT_VCPU },
56 	{ "fpe",	  VCPU_STAT(fpe_exits),		 KVM_STAT_VCPU },
57 	{ "msa_disabled", VCPU_STAT(msa_disabled_exits), KVM_STAT_VCPU },
58 	{ "flush_dcache", VCPU_STAT(flush_dcache_exits), KVM_STAT_VCPU },
59 	{ "halt_successful_poll", VCPU_STAT(halt_successful_poll), KVM_STAT_VCPU },
60 	{ "halt_attempted_poll", VCPU_STAT(halt_attempted_poll), KVM_STAT_VCPU },
61 	{ "halt_poll_invalid", VCPU_STAT(halt_poll_invalid), KVM_STAT_VCPU },
62 	{ "halt_wakeup",  VCPU_STAT(halt_wakeup),	 KVM_STAT_VCPU },
63 	{NULL}
64 };
65 
66 static int kvm_mips_reset_vcpu(struct kvm_vcpu *vcpu)
67 {
68 	int i;
69 
70 	for_each_possible_cpu(i) {
71 		vcpu->arch.guest_kernel_asid[i] = 0;
72 		vcpu->arch.guest_user_asid[i] = 0;
73 	}
74 
75 	return 0;
76 }
77 
78 /*
79  * XXXKYMA: We are simulatoring a processor that has the WII bit set in
80  * Config7, so we are "runnable" if interrupts are pending
81  */
82 int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
83 {
84 	return !!(vcpu->arch.pending_exceptions);
85 }
86 
87 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
88 {
89 	return 1;
90 }
91 
92 int kvm_arch_hardware_enable(void)
93 {
94 	return 0;
95 }
96 
97 int kvm_arch_hardware_setup(void)
98 {
99 	return 0;
100 }
101 
102 void kvm_arch_check_processor_compat(void *rtn)
103 {
104 	*(int *)rtn = 0;
105 }
106 
107 static void kvm_mips_init_tlbs(struct kvm *kvm)
108 {
109 	unsigned long wired;
110 
111 	/*
112 	 * Add a wired entry to the TLB, it is used to map the commpage to
113 	 * the Guest kernel
114 	 */
115 	wired = read_c0_wired();
116 	write_c0_wired(wired + 1);
117 	mtc0_tlbw_hazard();
118 	kvm->arch.commpage_tlb = wired;
119 
120 	kvm_debug("[%d] commpage TLB: %d\n", smp_processor_id(),
121 		  kvm->arch.commpage_tlb);
122 }
123 
124 static void kvm_mips_init_vm_percpu(void *arg)
125 {
126 	struct kvm *kvm = (struct kvm *)arg;
127 
128 	kvm_mips_init_tlbs(kvm);
129 	kvm_mips_callbacks->vm_init(kvm);
130 
131 }
132 
133 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
134 {
135 	if (atomic_inc_return(&kvm_mips_instance) == 1) {
136 		kvm_debug("%s: 1st KVM instance, setup host TLB parameters\n",
137 			  __func__);
138 		on_each_cpu(kvm_mips_init_vm_percpu, kvm, 1);
139 	}
140 
141 	return 0;
142 }
143 
144 bool kvm_arch_has_vcpu_debugfs(void)
145 {
146 	return false;
147 }
148 
149 int kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
150 {
151 	return 0;
152 }
153 
154 void kvm_mips_free_vcpus(struct kvm *kvm)
155 {
156 	unsigned int i;
157 	struct kvm_vcpu *vcpu;
158 
159 	/* Put the pages we reserved for the guest pmap */
160 	for (i = 0; i < kvm->arch.guest_pmap_npages; i++) {
161 		if (kvm->arch.guest_pmap[i] != KVM_INVALID_PAGE)
162 			kvm_release_pfn_clean(kvm->arch.guest_pmap[i]);
163 	}
164 	kfree(kvm->arch.guest_pmap);
165 
166 	kvm_for_each_vcpu(i, vcpu, kvm) {
167 		kvm_arch_vcpu_free(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_uninit_tlbs(void *arg)
181 {
182 	/* Restore wired count */
183 	write_c0_wired(0);
184 	mtc0_tlbw_hazard();
185 	/* Clear out all the TLBs */
186 	kvm_local_flush_tlb_all();
187 }
188 
189 void kvm_arch_destroy_vm(struct kvm *kvm)
190 {
191 	kvm_mips_free_vcpus(kvm);
192 
193 	/* If this is the last instance, restore wired count */
194 	if (atomic_dec_return(&kvm_mips_instance) == 0) {
195 		kvm_debug("%s: last KVM instance, restoring TLB parameters\n",
196 			  __func__);
197 		on_each_cpu(kvm_mips_uninit_tlbs, NULL, 1);
198 	}
199 }
200 
201 long kvm_arch_dev_ioctl(struct file *filp, unsigned int ioctl,
202 			unsigned long arg)
203 {
204 	return -ENOIOCTLCMD;
205 }
206 
207 int kvm_arch_create_memslot(struct kvm *kvm, struct kvm_memory_slot *slot,
208 			    unsigned long npages)
209 {
210 	return 0;
211 }
212 
213 int kvm_arch_prepare_memory_region(struct kvm *kvm,
214 				   struct kvm_memory_slot *memslot,
215 				   const struct kvm_userspace_memory_region *mem,
216 				   enum kvm_mr_change change)
217 {
218 	return 0;
219 }
220 
221 void kvm_arch_commit_memory_region(struct kvm *kvm,
222 				   const struct kvm_userspace_memory_region *mem,
223 				   const struct kvm_memory_slot *old,
224 				   const struct kvm_memory_slot *new,
225 				   enum kvm_mr_change change)
226 {
227 	unsigned long npages = 0;
228 	int i;
229 
230 	kvm_debug("%s: kvm: %p slot: %d, GPA: %llx, size: %llx, QVA: %llx\n",
231 		  __func__, kvm, mem->slot, mem->guest_phys_addr,
232 		  mem->memory_size, mem->userspace_addr);
233 
234 	/* Setup Guest PMAP table */
235 	if (!kvm->arch.guest_pmap) {
236 		if (mem->slot == 0)
237 			npages = mem->memory_size >> PAGE_SHIFT;
238 
239 		if (npages) {
240 			kvm->arch.guest_pmap_npages = npages;
241 			kvm->arch.guest_pmap =
242 			    kzalloc(npages * sizeof(unsigned long), GFP_KERNEL);
243 
244 			if (!kvm->arch.guest_pmap) {
245 				kvm_err("Failed to allocate guest PMAP\n");
246 				return;
247 			}
248 
249 			kvm_debug("Allocated space for Guest PMAP Table (%ld pages) @ %p\n",
250 				  npages, kvm->arch.guest_pmap);
251 
252 			/* Now setup the page table */
253 			for (i = 0; i < npages; i++)
254 				kvm->arch.guest_pmap[i] = KVM_INVALID_PAGE;
255 		}
256 	}
257 }
258 
259 static inline void dump_handler(const char *symbol, void *start, void *end)
260 {
261 	u32 *p;
262 
263 	pr_debug("LEAF(%s)\n", symbol);
264 
265 	pr_debug("\t.set push\n");
266 	pr_debug("\t.set noreorder\n");
267 
268 	for (p = start; p < (u32 *)end; ++p)
269 		pr_debug("\t.word\t0x%08x\t\t# %p\n", *p, p);
270 
271 	pr_debug("\t.set\tpop\n");
272 
273 	pr_debug("\tEND(%s)\n", symbol);
274 }
275 
276 struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
277 {
278 	int err, size;
279 	void *gebase, *p, *handler;
280 	int i;
281 
282 	struct kvm_vcpu *vcpu = kzalloc(sizeof(struct kvm_vcpu), GFP_KERNEL);
283 
284 	if (!vcpu) {
285 		err = -ENOMEM;
286 		goto out;
287 	}
288 
289 	err = kvm_vcpu_init(vcpu, kvm, id);
290 
291 	if (err)
292 		goto out_free_cpu;
293 
294 	kvm_debug("kvm @ %p: create cpu %d at %p\n", kvm, id, vcpu);
295 
296 	/*
297 	 * Allocate space for host mode exception handlers that handle
298 	 * guest mode exits
299 	 */
300 	if (cpu_has_veic || cpu_has_vint)
301 		size = 0x200 + VECTORSPACING * 64;
302 	else
303 		size = 0x4000;
304 
305 	gebase = kzalloc(ALIGN(size, PAGE_SIZE), GFP_KERNEL);
306 
307 	if (!gebase) {
308 		err = -ENOMEM;
309 		goto out_uninit_cpu;
310 	}
311 	kvm_debug("Allocated %d bytes for KVM Exception Handlers @ %p\n",
312 		  ALIGN(size, PAGE_SIZE), gebase);
313 
314 	/*
315 	 * Check new ebase actually fits in CP0_EBase. The lack of a write gate
316 	 * limits us to the low 512MB of physical address space. If the memory
317 	 * we allocate is out of range, just give up now.
318 	 */
319 	if (!cpu_has_ebase_wg && virt_to_phys(gebase) >= 0x20000000) {
320 		kvm_err("CP0_EBase.WG required for guest exception base %pK\n",
321 			gebase);
322 		err = -ENOMEM;
323 		goto out_free_gebase;
324 	}
325 
326 	/* Save new ebase */
327 	vcpu->arch.guest_ebase = gebase;
328 
329 	/* Build guest exception vectors dynamically in unmapped memory */
330 	handler = gebase + 0x2000;
331 
332 	/* TLB Refill, EXL = 0 */
333 	kvm_mips_build_exception(gebase, handler);
334 
335 	/* General Exception Entry point */
336 	kvm_mips_build_exception(gebase + 0x180, handler);
337 
338 	/* For vectored interrupts poke the exception code @ all offsets 0-7 */
339 	for (i = 0; i < 8; i++) {
340 		kvm_debug("L1 Vectored handler @ %p\n",
341 			  gebase + 0x200 + (i * VECTORSPACING));
342 		kvm_mips_build_exception(gebase + 0x200 + i * VECTORSPACING,
343 					 handler);
344 	}
345 
346 	/* General exit handler */
347 	p = handler;
348 	p = kvm_mips_build_exit(p);
349 
350 	/* Guest entry routine */
351 	vcpu->arch.vcpu_run = p;
352 	p = kvm_mips_build_vcpu_run(p);
353 
354 	/* Dump the generated code */
355 	pr_debug("#include <asm/asm.h>\n");
356 	pr_debug("#include <asm/regdef.h>\n");
357 	pr_debug("\n");
358 	dump_handler("kvm_vcpu_run", vcpu->arch.vcpu_run, p);
359 	dump_handler("kvm_gen_exc", gebase + 0x180, gebase + 0x200);
360 	dump_handler("kvm_exit", gebase + 0x2000, vcpu->arch.vcpu_run);
361 
362 	/* Invalidate the icache for these ranges */
363 	flush_icache_range((unsigned long)gebase,
364 			   (unsigned long)gebase + ALIGN(size, PAGE_SIZE));
365 
366 	/*
367 	 * Allocate comm page for guest kernel, a TLB will be reserved for
368 	 * mapping GVA @ 0xFFFF8000 to this page
369 	 */
370 	vcpu->arch.kseg0_commpage = kzalloc(PAGE_SIZE << 1, GFP_KERNEL);
371 
372 	if (!vcpu->arch.kseg0_commpage) {
373 		err = -ENOMEM;
374 		goto out_free_gebase;
375 	}
376 
377 	kvm_debug("Allocated COMM page @ %p\n", vcpu->arch.kseg0_commpage);
378 	kvm_mips_commpage_init(vcpu);
379 
380 	/* Init */
381 	vcpu->arch.last_sched_cpu = -1;
382 
383 	/* Start off the timer */
384 	kvm_mips_init_count(vcpu);
385 
386 	return vcpu;
387 
388 out_free_gebase:
389 	kfree(gebase);
390 
391 out_uninit_cpu:
392 	kvm_vcpu_uninit(vcpu);
393 
394 out_free_cpu:
395 	kfree(vcpu);
396 
397 out:
398 	return ERR_PTR(err);
399 }
400 
401 void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
402 {
403 	hrtimer_cancel(&vcpu->arch.comparecount_timer);
404 
405 	kvm_vcpu_uninit(vcpu);
406 
407 	kvm_mips_dump_stats(vcpu);
408 
409 	kfree(vcpu->arch.guest_ebase);
410 	kfree(vcpu->arch.kseg0_commpage);
411 	kfree(vcpu);
412 }
413 
414 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
415 {
416 	kvm_arch_vcpu_free(vcpu);
417 }
418 
419 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
420 					struct kvm_guest_debug *dbg)
421 {
422 	return -ENOIOCTLCMD;
423 }
424 
425 /* Must be called with preemption disabled, just before entering guest */
426 static void kvm_mips_check_asids(struct kvm_vcpu *vcpu)
427 {
428 	struct mips_coproc *cop0 = vcpu->arch.cop0;
429 	int i, cpu = smp_processor_id();
430 	unsigned int gasid;
431 
432 	/*
433 	 * Lazy host ASID regeneration for guest user mode.
434 	 * If the guest ASID has changed since the last guest usermode
435 	 * execution, regenerate the host ASID so as to invalidate stale TLB
436 	 * entries.
437 	 */
438 	if (!KVM_GUEST_KERNEL_MODE(vcpu)) {
439 		gasid = kvm_read_c0_guest_entryhi(cop0) & KVM_ENTRYHI_ASID;
440 		if (gasid != vcpu->arch.last_user_gasid) {
441 			kvm_get_new_mmu_context(&vcpu->arch.guest_user_mm, cpu,
442 						vcpu);
443 			vcpu->arch.guest_user_asid[cpu] =
444 				vcpu->arch.guest_user_mm.context.asid[cpu];
445 			for_each_possible_cpu(i)
446 				if (i != cpu)
447 					vcpu->arch.guest_user_asid[cpu] = 0;
448 			vcpu->arch.last_user_gasid = gasid;
449 		}
450 	}
451 }
452 
453 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
454 {
455 	int r = 0;
456 	sigset_t sigsaved;
457 
458 	if (vcpu->sigset_active)
459 		sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);
460 
461 	if (vcpu->mmio_needed) {
462 		if (!vcpu->mmio_is_write)
463 			kvm_mips_complete_mmio_load(vcpu, run);
464 		vcpu->mmio_needed = 0;
465 	}
466 
467 	lose_fpu(1);
468 
469 	local_irq_disable();
470 	/* Check if we have any exceptions/interrupts pending */
471 	kvm_mips_deliver_interrupts(vcpu,
472 				    kvm_read_c0_guest_cause(vcpu->arch.cop0));
473 
474 	guest_enter_irqoff();
475 
476 	/* Disable hardware page table walking while in guest */
477 	htw_stop();
478 
479 	trace_kvm_enter(vcpu);
480 
481 	kvm_mips_check_asids(vcpu);
482 
483 	r = vcpu->arch.vcpu_run(run, vcpu);
484 	trace_kvm_out(vcpu);
485 
486 	/* Re-enable HTW before enabling interrupts */
487 	htw_start();
488 
489 	guest_exit_irqoff();
490 	local_irq_enable();
491 
492 	if (vcpu->sigset_active)
493 		sigprocmask(SIG_SETMASK, &sigsaved, NULL);
494 
495 	return r;
496 }
497 
498 int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
499 			     struct kvm_mips_interrupt *irq)
500 {
501 	int intr = (int)irq->irq;
502 	struct kvm_vcpu *dvcpu = NULL;
503 
504 	if (intr == 3 || intr == -3 || intr == 4 || intr == -4)
505 		kvm_debug("%s: CPU: %d, INTR: %d\n", __func__, irq->cpu,
506 			  (int)intr);
507 
508 	if (irq->cpu == -1)
509 		dvcpu = vcpu;
510 	else
511 		dvcpu = vcpu->kvm->vcpus[irq->cpu];
512 
513 	if (intr == 2 || intr == 3 || intr == 4) {
514 		kvm_mips_callbacks->queue_io_int(dvcpu, irq);
515 
516 	} else if (intr == -2 || intr == -3 || intr == -4) {
517 		kvm_mips_callbacks->dequeue_io_int(dvcpu, irq);
518 	} else {
519 		kvm_err("%s: invalid interrupt ioctl (%d:%d)\n", __func__,
520 			irq->cpu, irq->irq);
521 		return -EINVAL;
522 	}
523 
524 	dvcpu->arch.wait = 0;
525 
526 	if (swait_active(&dvcpu->wq))
527 		swake_up(&dvcpu->wq);
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 	KVM_REG_MIPS_CP0_INDEX,
585 	KVM_REG_MIPS_CP0_CONTEXT,
586 	KVM_REG_MIPS_CP0_USERLOCAL,
587 	KVM_REG_MIPS_CP0_PAGEMASK,
588 	KVM_REG_MIPS_CP0_WIRED,
589 	KVM_REG_MIPS_CP0_HWRENA,
590 	KVM_REG_MIPS_CP0_BADVADDR,
591 	KVM_REG_MIPS_CP0_COUNT,
592 	KVM_REG_MIPS_CP0_ENTRYHI,
593 	KVM_REG_MIPS_CP0_COMPARE,
594 	KVM_REG_MIPS_CP0_STATUS,
595 	KVM_REG_MIPS_CP0_CAUSE,
596 	KVM_REG_MIPS_CP0_EPC,
597 	KVM_REG_MIPS_CP0_PRID,
598 	KVM_REG_MIPS_CP0_CONFIG,
599 	KVM_REG_MIPS_CP0_CONFIG1,
600 	KVM_REG_MIPS_CP0_CONFIG2,
601 	KVM_REG_MIPS_CP0_CONFIG3,
602 	KVM_REG_MIPS_CP0_CONFIG4,
603 	KVM_REG_MIPS_CP0_CONFIG5,
604 	KVM_REG_MIPS_CP0_CONFIG7,
605 	KVM_REG_MIPS_CP0_ERROREPC,
606 
607 	KVM_REG_MIPS_COUNT_CTL,
608 	KVM_REG_MIPS_COUNT_RESUME,
609 	KVM_REG_MIPS_COUNT_HZ,
610 };
611 
612 static u64 kvm_mips_get_one_regs_fpu[] = {
613 	KVM_REG_MIPS_FCR_IR,
614 	KVM_REG_MIPS_FCR_CSR,
615 };
616 
617 static u64 kvm_mips_get_one_regs_msa[] = {
618 	KVM_REG_MIPS_MSA_IR,
619 	KVM_REG_MIPS_MSA_CSR,
620 };
621 
622 static u64 kvm_mips_get_one_regs_kscratch[] = {
623 	KVM_REG_MIPS_CP0_KSCRATCH1,
624 	KVM_REG_MIPS_CP0_KSCRATCH2,
625 	KVM_REG_MIPS_CP0_KSCRATCH3,
626 	KVM_REG_MIPS_CP0_KSCRATCH4,
627 	KVM_REG_MIPS_CP0_KSCRATCH5,
628 	KVM_REG_MIPS_CP0_KSCRATCH6,
629 };
630 
631 static unsigned long kvm_mips_num_regs(struct kvm_vcpu *vcpu)
632 {
633 	unsigned long ret;
634 
635 	ret = ARRAY_SIZE(kvm_mips_get_one_regs);
636 	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
637 		ret += ARRAY_SIZE(kvm_mips_get_one_regs_fpu) + 48;
638 		/* odd doubles */
639 		if (boot_cpu_data.fpu_id & MIPS_FPIR_F64)
640 			ret += 16;
641 	}
642 	if (kvm_mips_guest_can_have_msa(&vcpu->arch))
643 		ret += ARRAY_SIZE(kvm_mips_get_one_regs_msa) + 32;
644 	ret += __arch_hweight8(vcpu->arch.kscratch_enabled);
645 	ret += kvm_mips_callbacks->num_regs(vcpu);
646 
647 	return ret;
648 }
649 
650 static int kvm_mips_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices)
651 {
652 	u64 index;
653 	unsigned int i;
654 
655 	if (copy_to_user(indices, kvm_mips_get_one_regs,
656 			 sizeof(kvm_mips_get_one_regs)))
657 		return -EFAULT;
658 	indices += ARRAY_SIZE(kvm_mips_get_one_regs);
659 
660 	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
661 		if (copy_to_user(indices, kvm_mips_get_one_regs_fpu,
662 				 sizeof(kvm_mips_get_one_regs_fpu)))
663 			return -EFAULT;
664 		indices += ARRAY_SIZE(kvm_mips_get_one_regs_fpu);
665 
666 		for (i = 0; i < 32; ++i) {
667 			index = KVM_REG_MIPS_FPR_32(i);
668 			if (copy_to_user(indices, &index, sizeof(index)))
669 				return -EFAULT;
670 			++indices;
671 
672 			/* skip odd doubles if no F64 */
673 			if (i & 1 && !(boot_cpu_data.fpu_id & MIPS_FPIR_F64))
674 				continue;
675 
676 			index = KVM_REG_MIPS_FPR_64(i);
677 			if (copy_to_user(indices, &index, sizeof(index)))
678 				return -EFAULT;
679 			++indices;
680 		}
681 	}
682 
683 	if (kvm_mips_guest_can_have_msa(&vcpu->arch)) {
684 		if (copy_to_user(indices, kvm_mips_get_one_regs_msa,
685 				 sizeof(kvm_mips_get_one_regs_msa)))
686 			return -EFAULT;
687 		indices += ARRAY_SIZE(kvm_mips_get_one_regs_msa);
688 
689 		for (i = 0; i < 32; ++i) {
690 			index = KVM_REG_MIPS_VEC_128(i);
691 			if (copy_to_user(indices, &index, sizeof(index)))
692 				return -EFAULT;
693 			++indices;
694 		}
695 	}
696 
697 	for (i = 0; i < 6; ++i) {
698 		if (!(vcpu->arch.kscratch_enabled & BIT(i + 2)))
699 			continue;
700 
701 		if (copy_to_user(indices, &kvm_mips_get_one_regs_kscratch[i],
702 				 sizeof(kvm_mips_get_one_regs_kscratch[i])))
703 			return -EFAULT;
704 		++indices;
705 	}
706 
707 	return kvm_mips_callbacks->copy_reg_indices(vcpu, indices);
708 }
709 
710 static int kvm_mips_get_reg(struct kvm_vcpu *vcpu,
711 			    const struct kvm_one_reg *reg)
712 {
713 	struct mips_coproc *cop0 = vcpu->arch.cop0;
714 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
715 	int ret;
716 	s64 v;
717 	s64 vs[2];
718 	unsigned int idx;
719 
720 	switch (reg->id) {
721 	/* General purpose registers */
722 	case KVM_REG_MIPS_R0 ... KVM_REG_MIPS_R31:
723 		v = (long)vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0];
724 		break;
725 #ifndef CONFIG_CPU_MIPSR6
726 	case KVM_REG_MIPS_HI:
727 		v = (long)vcpu->arch.hi;
728 		break;
729 	case KVM_REG_MIPS_LO:
730 		v = (long)vcpu->arch.lo;
731 		break;
732 #endif
733 	case KVM_REG_MIPS_PC:
734 		v = (long)vcpu->arch.pc;
735 		break;
736 
737 	/* Floating point registers */
738 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
739 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
740 			return -EINVAL;
741 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
742 		/* Odd singles in top of even double when FR=0 */
743 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
744 			v = get_fpr32(&fpu->fpr[idx], 0);
745 		else
746 			v = get_fpr32(&fpu->fpr[idx & ~1], idx & 1);
747 		break;
748 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
749 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
750 			return -EINVAL;
751 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
752 		/* Can't access odd doubles in FR=0 mode */
753 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
754 			return -EINVAL;
755 		v = get_fpr64(&fpu->fpr[idx], 0);
756 		break;
757 	case KVM_REG_MIPS_FCR_IR:
758 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
759 			return -EINVAL;
760 		v = boot_cpu_data.fpu_id;
761 		break;
762 	case KVM_REG_MIPS_FCR_CSR:
763 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
764 			return -EINVAL;
765 		v = fpu->fcr31;
766 		break;
767 
768 	/* MIPS SIMD Architecture (MSA) registers */
769 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
770 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
771 			return -EINVAL;
772 		/* Can't access MSA registers in FR=0 mode */
773 		if (!(kvm_read_c0_guest_status(cop0) & ST0_FR))
774 			return -EINVAL;
775 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
776 #ifdef CONFIG_CPU_LITTLE_ENDIAN
777 		/* least significant byte first */
778 		vs[0] = get_fpr64(&fpu->fpr[idx], 0);
779 		vs[1] = get_fpr64(&fpu->fpr[idx], 1);
780 #else
781 		/* most significant byte first */
782 		vs[0] = get_fpr64(&fpu->fpr[idx], 1);
783 		vs[1] = get_fpr64(&fpu->fpr[idx], 0);
784 #endif
785 		break;
786 	case KVM_REG_MIPS_MSA_IR:
787 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
788 			return -EINVAL;
789 		v = boot_cpu_data.msa_id;
790 		break;
791 	case KVM_REG_MIPS_MSA_CSR:
792 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
793 			return -EINVAL;
794 		v = fpu->msacsr;
795 		break;
796 
797 	/* Co-processor 0 registers */
798 	case KVM_REG_MIPS_CP0_INDEX:
799 		v = (long)kvm_read_c0_guest_index(cop0);
800 		break;
801 	case KVM_REG_MIPS_CP0_CONTEXT:
802 		v = (long)kvm_read_c0_guest_context(cop0);
803 		break;
804 	case KVM_REG_MIPS_CP0_USERLOCAL:
805 		v = (long)kvm_read_c0_guest_userlocal(cop0);
806 		break;
807 	case KVM_REG_MIPS_CP0_PAGEMASK:
808 		v = (long)kvm_read_c0_guest_pagemask(cop0);
809 		break;
810 	case KVM_REG_MIPS_CP0_WIRED:
811 		v = (long)kvm_read_c0_guest_wired(cop0);
812 		break;
813 	case KVM_REG_MIPS_CP0_HWRENA:
814 		v = (long)kvm_read_c0_guest_hwrena(cop0);
815 		break;
816 	case KVM_REG_MIPS_CP0_BADVADDR:
817 		v = (long)kvm_read_c0_guest_badvaddr(cop0);
818 		break;
819 	case KVM_REG_MIPS_CP0_ENTRYHI:
820 		v = (long)kvm_read_c0_guest_entryhi(cop0);
821 		break;
822 	case KVM_REG_MIPS_CP0_COMPARE:
823 		v = (long)kvm_read_c0_guest_compare(cop0);
824 		break;
825 	case KVM_REG_MIPS_CP0_STATUS:
826 		v = (long)kvm_read_c0_guest_status(cop0);
827 		break;
828 	case KVM_REG_MIPS_CP0_CAUSE:
829 		v = (long)kvm_read_c0_guest_cause(cop0);
830 		break;
831 	case KVM_REG_MIPS_CP0_EPC:
832 		v = (long)kvm_read_c0_guest_epc(cop0);
833 		break;
834 	case KVM_REG_MIPS_CP0_PRID:
835 		v = (long)kvm_read_c0_guest_prid(cop0);
836 		break;
837 	case KVM_REG_MIPS_CP0_CONFIG:
838 		v = (long)kvm_read_c0_guest_config(cop0);
839 		break;
840 	case KVM_REG_MIPS_CP0_CONFIG1:
841 		v = (long)kvm_read_c0_guest_config1(cop0);
842 		break;
843 	case KVM_REG_MIPS_CP0_CONFIG2:
844 		v = (long)kvm_read_c0_guest_config2(cop0);
845 		break;
846 	case KVM_REG_MIPS_CP0_CONFIG3:
847 		v = (long)kvm_read_c0_guest_config3(cop0);
848 		break;
849 	case KVM_REG_MIPS_CP0_CONFIG4:
850 		v = (long)kvm_read_c0_guest_config4(cop0);
851 		break;
852 	case KVM_REG_MIPS_CP0_CONFIG5:
853 		v = (long)kvm_read_c0_guest_config5(cop0);
854 		break;
855 	case KVM_REG_MIPS_CP0_CONFIG7:
856 		v = (long)kvm_read_c0_guest_config7(cop0);
857 		break;
858 	case KVM_REG_MIPS_CP0_ERROREPC:
859 		v = (long)kvm_read_c0_guest_errorepc(cop0);
860 		break;
861 	case KVM_REG_MIPS_CP0_KSCRATCH1 ... KVM_REG_MIPS_CP0_KSCRATCH6:
862 		idx = reg->id - KVM_REG_MIPS_CP0_KSCRATCH1 + 2;
863 		if (!(vcpu->arch.kscratch_enabled & BIT(idx)))
864 			return -EINVAL;
865 		switch (idx) {
866 		case 2:
867 			v = (long)kvm_read_c0_guest_kscratch1(cop0);
868 			break;
869 		case 3:
870 			v = (long)kvm_read_c0_guest_kscratch2(cop0);
871 			break;
872 		case 4:
873 			v = (long)kvm_read_c0_guest_kscratch3(cop0);
874 			break;
875 		case 5:
876 			v = (long)kvm_read_c0_guest_kscratch4(cop0);
877 			break;
878 		case 6:
879 			v = (long)kvm_read_c0_guest_kscratch5(cop0);
880 			break;
881 		case 7:
882 			v = (long)kvm_read_c0_guest_kscratch6(cop0);
883 			break;
884 		}
885 		break;
886 	/* registers to be handled specially */
887 	default:
888 		ret = kvm_mips_callbacks->get_one_reg(vcpu, reg, &v);
889 		if (ret)
890 			return ret;
891 		break;
892 	}
893 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
894 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
895 
896 		return put_user(v, uaddr64);
897 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
898 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
899 		u32 v32 = (u32)v;
900 
901 		return put_user(v32, uaddr32);
902 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
903 		void __user *uaddr = (void __user *)(long)reg->addr;
904 
905 		return copy_to_user(uaddr, vs, 16) ? -EFAULT : 0;
906 	} else {
907 		return -EINVAL;
908 	}
909 }
910 
911 static int kvm_mips_set_reg(struct kvm_vcpu *vcpu,
912 			    const struct kvm_one_reg *reg)
913 {
914 	struct mips_coproc *cop0 = vcpu->arch.cop0;
915 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
916 	s64 v;
917 	s64 vs[2];
918 	unsigned int idx;
919 
920 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
921 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
922 
923 		if (get_user(v, uaddr64) != 0)
924 			return -EFAULT;
925 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
926 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
927 		s32 v32;
928 
929 		if (get_user(v32, uaddr32) != 0)
930 			return -EFAULT;
931 		v = (s64)v32;
932 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
933 		void __user *uaddr = (void __user *)(long)reg->addr;
934 
935 		return copy_from_user(vs, uaddr, 16) ? -EFAULT : 0;
936 	} else {
937 		return -EINVAL;
938 	}
939 
940 	switch (reg->id) {
941 	/* General purpose registers */
942 	case KVM_REG_MIPS_R0:
943 		/* Silently ignore requests to set $0 */
944 		break;
945 	case KVM_REG_MIPS_R1 ... KVM_REG_MIPS_R31:
946 		vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0] = v;
947 		break;
948 #ifndef CONFIG_CPU_MIPSR6
949 	case KVM_REG_MIPS_HI:
950 		vcpu->arch.hi = v;
951 		break;
952 	case KVM_REG_MIPS_LO:
953 		vcpu->arch.lo = v;
954 		break;
955 #endif
956 	case KVM_REG_MIPS_PC:
957 		vcpu->arch.pc = v;
958 		break;
959 
960 	/* Floating point registers */
961 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
962 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
963 			return -EINVAL;
964 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
965 		/* Odd singles in top of even double when FR=0 */
966 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
967 			set_fpr32(&fpu->fpr[idx], 0, v);
968 		else
969 			set_fpr32(&fpu->fpr[idx & ~1], idx & 1, v);
970 		break;
971 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
972 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
973 			return -EINVAL;
974 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
975 		/* Can't access odd doubles in FR=0 mode */
976 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
977 			return -EINVAL;
978 		set_fpr64(&fpu->fpr[idx], 0, v);
979 		break;
980 	case KVM_REG_MIPS_FCR_IR:
981 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
982 			return -EINVAL;
983 		/* Read-only */
984 		break;
985 	case KVM_REG_MIPS_FCR_CSR:
986 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
987 			return -EINVAL;
988 		fpu->fcr31 = v;
989 		break;
990 
991 	/* MIPS SIMD Architecture (MSA) registers */
992 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
993 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
994 			return -EINVAL;
995 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
996 #ifdef CONFIG_CPU_LITTLE_ENDIAN
997 		/* least significant byte first */
998 		set_fpr64(&fpu->fpr[idx], 0, vs[0]);
999 		set_fpr64(&fpu->fpr[idx], 1, vs[1]);
1000 #else
1001 		/* most significant byte first */
1002 		set_fpr64(&fpu->fpr[idx], 1, vs[0]);
1003 		set_fpr64(&fpu->fpr[idx], 0, vs[1]);
1004 #endif
1005 		break;
1006 	case KVM_REG_MIPS_MSA_IR:
1007 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
1008 			return -EINVAL;
1009 		/* Read-only */
1010 		break;
1011 	case KVM_REG_MIPS_MSA_CSR:
1012 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
1013 			return -EINVAL;
1014 		fpu->msacsr = v;
1015 		break;
1016 
1017 	/* Co-processor 0 registers */
1018 	case KVM_REG_MIPS_CP0_INDEX:
1019 		kvm_write_c0_guest_index(cop0, v);
1020 		break;
1021 	case KVM_REG_MIPS_CP0_CONTEXT:
1022 		kvm_write_c0_guest_context(cop0, v);
1023 		break;
1024 	case KVM_REG_MIPS_CP0_USERLOCAL:
1025 		kvm_write_c0_guest_userlocal(cop0, v);
1026 		break;
1027 	case KVM_REG_MIPS_CP0_PAGEMASK:
1028 		kvm_write_c0_guest_pagemask(cop0, v);
1029 		break;
1030 	case KVM_REG_MIPS_CP0_WIRED:
1031 		kvm_write_c0_guest_wired(cop0, v);
1032 		break;
1033 	case KVM_REG_MIPS_CP0_HWRENA:
1034 		kvm_write_c0_guest_hwrena(cop0, v);
1035 		break;
1036 	case KVM_REG_MIPS_CP0_BADVADDR:
1037 		kvm_write_c0_guest_badvaddr(cop0, v);
1038 		break;
1039 	case KVM_REG_MIPS_CP0_ENTRYHI:
1040 		kvm_write_c0_guest_entryhi(cop0, v);
1041 		break;
1042 	case KVM_REG_MIPS_CP0_STATUS:
1043 		kvm_write_c0_guest_status(cop0, v);
1044 		break;
1045 	case KVM_REG_MIPS_CP0_EPC:
1046 		kvm_write_c0_guest_epc(cop0, v);
1047 		break;
1048 	case KVM_REG_MIPS_CP0_PRID:
1049 		kvm_write_c0_guest_prid(cop0, v);
1050 		break;
1051 	case KVM_REG_MIPS_CP0_ERROREPC:
1052 		kvm_write_c0_guest_errorepc(cop0, v);
1053 		break;
1054 	case KVM_REG_MIPS_CP0_KSCRATCH1 ... KVM_REG_MIPS_CP0_KSCRATCH6:
1055 		idx = reg->id - KVM_REG_MIPS_CP0_KSCRATCH1 + 2;
1056 		if (!(vcpu->arch.kscratch_enabled & BIT(idx)))
1057 			return -EINVAL;
1058 		switch (idx) {
1059 		case 2:
1060 			kvm_write_c0_guest_kscratch1(cop0, v);
1061 			break;
1062 		case 3:
1063 			kvm_write_c0_guest_kscratch2(cop0, v);
1064 			break;
1065 		case 4:
1066 			kvm_write_c0_guest_kscratch3(cop0, v);
1067 			break;
1068 		case 5:
1069 			kvm_write_c0_guest_kscratch4(cop0, v);
1070 			break;
1071 		case 6:
1072 			kvm_write_c0_guest_kscratch5(cop0, v);
1073 			break;
1074 		case 7:
1075 			kvm_write_c0_guest_kscratch6(cop0, v);
1076 			break;
1077 		}
1078 		break;
1079 	/* registers to be handled specially */
1080 	default:
1081 		return kvm_mips_callbacks->set_one_reg(vcpu, reg, v);
1082 	}
1083 	return 0;
1084 }
1085 
1086 static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
1087 				     struct kvm_enable_cap *cap)
1088 {
1089 	int r = 0;
1090 
1091 	if (!kvm_vm_ioctl_check_extension(vcpu->kvm, cap->cap))
1092 		return -EINVAL;
1093 	if (cap->flags)
1094 		return -EINVAL;
1095 	if (cap->args[0])
1096 		return -EINVAL;
1097 
1098 	switch (cap->cap) {
1099 	case KVM_CAP_MIPS_FPU:
1100 		vcpu->arch.fpu_enabled = true;
1101 		break;
1102 	case KVM_CAP_MIPS_MSA:
1103 		vcpu->arch.msa_enabled = true;
1104 		break;
1105 	default:
1106 		r = -EINVAL;
1107 		break;
1108 	}
1109 
1110 	return r;
1111 }
1112 
1113 long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl,
1114 			 unsigned long arg)
1115 {
1116 	struct kvm_vcpu *vcpu = filp->private_data;
1117 	void __user *argp = (void __user *)arg;
1118 	long r;
1119 
1120 	switch (ioctl) {
1121 	case KVM_SET_ONE_REG:
1122 	case KVM_GET_ONE_REG: {
1123 		struct kvm_one_reg reg;
1124 
1125 		if (copy_from_user(&reg, argp, sizeof(reg)))
1126 			return -EFAULT;
1127 		if (ioctl == KVM_SET_ONE_REG)
1128 			return kvm_mips_set_reg(vcpu, &reg);
1129 		else
1130 			return kvm_mips_get_reg(vcpu, &reg);
1131 	}
1132 	case KVM_GET_REG_LIST: {
1133 		struct kvm_reg_list __user *user_list = argp;
1134 		struct kvm_reg_list reg_list;
1135 		unsigned n;
1136 
1137 		if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
1138 			return -EFAULT;
1139 		n = reg_list.n;
1140 		reg_list.n = kvm_mips_num_regs(vcpu);
1141 		if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
1142 			return -EFAULT;
1143 		if (n < reg_list.n)
1144 			return -E2BIG;
1145 		return kvm_mips_copy_reg_indices(vcpu, user_list->reg);
1146 	}
1147 	case KVM_NMI:
1148 		/* Treat the NMI as a CPU reset */
1149 		r = kvm_mips_reset_vcpu(vcpu);
1150 		break;
1151 	case KVM_INTERRUPT:
1152 		{
1153 			struct kvm_mips_interrupt irq;
1154 
1155 			r = -EFAULT;
1156 			if (copy_from_user(&irq, argp, sizeof(irq)))
1157 				goto out;
1158 
1159 			kvm_debug("[%d] %s: irq: %d\n", vcpu->vcpu_id, __func__,
1160 				  irq.irq);
1161 
1162 			r = kvm_vcpu_ioctl_interrupt(vcpu, &irq);
1163 			break;
1164 		}
1165 	case KVM_ENABLE_CAP: {
1166 		struct kvm_enable_cap cap;
1167 
1168 		r = -EFAULT;
1169 		if (copy_from_user(&cap, argp, sizeof(cap)))
1170 			goto out;
1171 		r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
1172 		break;
1173 	}
1174 	default:
1175 		r = -ENOIOCTLCMD;
1176 	}
1177 
1178 out:
1179 	return r;
1180 }
1181 
1182 /* Get (and clear) the dirty memory log for a memory slot. */
1183 int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log)
1184 {
1185 	struct kvm_memslots *slots;
1186 	struct kvm_memory_slot *memslot;
1187 	unsigned long ga, ga_end;
1188 	int is_dirty = 0;
1189 	int r;
1190 	unsigned long n;
1191 
1192 	mutex_lock(&kvm->slots_lock);
1193 
1194 	r = kvm_get_dirty_log(kvm, log, &is_dirty);
1195 	if (r)
1196 		goto out;
1197 
1198 	/* If nothing is dirty, don't bother messing with page tables. */
1199 	if (is_dirty) {
1200 		slots = kvm_memslots(kvm);
1201 		memslot = id_to_memslot(slots, log->slot);
1202 
1203 		ga = memslot->base_gfn << PAGE_SHIFT;
1204 		ga_end = ga + (memslot->npages << PAGE_SHIFT);
1205 
1206 		kvm_info("%s: dirty, ga: %#lx, ga_end %#lx\n", __func__, ga,
1207 			 ga_end);
1208 
1209 		n = kvm_dirty_bitmap_bytes(memslot);
1210 		memset(memslot->dirty_bitmap, 0, n);
1211 	}
1212 
1213 	r = 0;
1214 out:
1215 	mutex_unlock(&kvm->slots_lock);
1216 	return r;
1217 
1218 }
1219 
1220 long kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
1221 {
1222 	long r;
1223 
1224 	switch (ioctl) {
1225 	default:
1226 		r = -ENOIOCTLCMD;
1227 	}
1228 
1229 	return r;
1230 }
1231 
1232 int kvm_arch_init(void *opaque)
1233 {
1234 	if (kvm_mips_callbacks) {
1235 		kvm_err("kvm: module already exists\n");
1236 		return -EEXIST;
1237 	}
1238 
1239 	return kvm_mips_emulation_init(&kvm_mips_callbacks);
1240 }
1241 
1242 void kvm_arch_exit(void)
1243 {
1244 	kvm_mips_callbacks = NULL;
1245 }
1246 
1247 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
1248 				  struct kvm_sregs *sregs)
1249 {
1250 	return -ENOIOCTLCMD;
1251 }
1252 
1253 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
1254 				  struct kvm_sregs *sregs)
1255 {
1256 	return -ENOIOCTLCMD;
1257 }
1258 
1259 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
1260 {
1261 }
1262 
1263 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1264 {
1265 	return -ENOIOCTLCMD;
1266 }
1267 
1268 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1269 {
1270 	return -ENOIOCTLCMD;
1271 }
1272 
1273 int kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
1274 {
1275 	return VM_FAULT_SIGBUS;
1276 }
1277 
1278 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
1279 {
1280 	int r;
1281 
1282 	switch (ext) {
1283 	case KVM_CAP_ONE_REG:
1284 	case KVM_CAP_ENABLE_CAP:
1285 		r = 1;
1286 		break;
1287 	case KVM_CAP_COALESCED_MMIO:
1288 		r = KVM_COALESCED_MMIO_PAGE_OFFSET;
1289 		break;
1290 	case KVM_CAP_MIPS_FPU:
1291 		/* We don't handle systems with inconsistent cpu_has_fpu */
1292 		r = !!raw_cpu_has_fpu;
1293 		break;
1294 	case KVM_CAP_MIPS_MSA:
1295 		/*
1296 		 * We don't support MSA vector partitioning yet:
1297 		 * 1) It would require explicit support which can't be tested
1298 		 *    yet due to lack of support in current hardware.
1299 		 * 2) It extends the state that would need to be saved/restored
1300 		 *    by e.g. QEMU for migration.
1301 		 *
1302 		 * When vector partitioning hardware becomes available, support
1303 		 * could be added by requiring a flag when enabling
1304 		 * KVM_CAP_MIPS_MSA capability to indicate that userland knows
1305 		 * to save/restore the appropriate extra state.
1306 		 */
1307 		r = cpu_has_msa && !(boot_cpu_data.msa_id & MSA_IR_WRPF);
1308 		break;
1309 	default:
1310 		r = 0;
1311 		break;
1312 	}
1313 	return r;
1314 }
1315 
1316 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
1317 {
1318 	return kvm_mips_pending_timer(vcpu);
1319 }
1320 
1321 int kvm_arch_vcpu_dump_regs(struct kvm_vcpu *vcpu)
1322 {
1323 	int i;
1324 	struct mips_coproc *cop0;
1325 
1326 	if (!vcpu)
1327 		return -1;
1328 
1329 	kvm_debug("VCPU Register Dump:\n");
1330 	kvm_debug("\tpc = 0x%08lx\n", vcpu->arch.pc);
1331 	kvm_debug("\texceptions: %08lx\n", vcpu->arch.pending_exceptions);
1332 
1333 	for (i = 0; i < 32; i += 4) {
1334 		kvm_debug("\tgpr%02d: %08lx %08lx %08lx %08lx\n", i,
1335 		       vcpu->arch.gprs[i],
1336 		       vcpu->arch.gprs[i + 1],
1337 		       vcpu->arch.gprs[i + 2], vcpu->arch.gprs[i + 3]);
1338 	}
1339 	kvm_debug("\thi: 0x%08lx\n", vcpu->arch.hi);
1340 	kvm_debug("\tlo: 0x%08lx\n", vcpu->arch.lo);
1341 
1342 	cop0 = vcpu->arch.cop0;
1343 	kvm_debug("\tStatus: 0x%08lx, Cause: 0x%08lx\n",
1344 		  kvm_read_c0_guest_status(cop0),
1345 		  kvm_read_c0_guest_cause(cop0));
1346 
1347 	kvm_debug("\tEPC: 0x%08lx\n", kvm_read_c0_guest_epc(cop0));
1348 
1349 	return 0;
1350 }
1351 
1352 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1353 {
1354 	int i;
1355 
1356 	for (i = 1; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1357 		vcpu->arch.gprs[i] = regs->gpr[i];
1358 	vcpu->arch.gprs[0] = 0; /* zero is special, and cannot be set. */
1359 	vcpu->arch.hi = regs->hi;
1360 	vcpu->arch.lo = regs->lo;
1361 	vcpu->arch.pc = regs->pc;
1362 
1363 	return 0;
1364 }
1365 
1366 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1367 {
1368 	int i;
1369 
1370 	for (i = 0; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1371 		regs->gpr[i] = vcpu->arch.gprs[i];
1372 
1373 	regs->hi = vcpu->arch.hi;
1374 	regs->lo = vcpu->arch.lo;
1375 	regs->pc = vcpu->arch.pc;
1376 
1377 	return 0;
1378 }
1379 
1380 static void kvm_mips_comparecount_func(unsigned long data)
1381 {
1382 	struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data;
1383 
1384 	kvm_mips_callbacks->queue_timer_int(vcpu);
1385 
1386 	vcpu->arch.wait = 0;
1387 	if (swait_active(&vcpu->wq))
1388 		swake_up(&vcpu->wq);
1389 }
1390 
1391 /* low level hrtimer wake routine */
1392 static enum hrtimer_restart kvm_mips_comparecount_wakeup(struct hrtimer *timer)
1393 {
1394 	struct kvm_vcpu *vcpu;
1395 
1396 	vcpu = container_of(timer, struct kvm_vcpu, arch.comparecount_timer);
1397 	kvm_mips_comparecount_func((unsigned long) vcpu);
1398 	return kvm_mips_count_timeout(vcpu);
1399 }
1400 
1401 int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
1402 {
1403 	kvm_mips_callbacks->vcpu_init(vcpu);
1404 	hrtimer_init(&vcpu->arch.comparecount_timer, CLOCK_MONOTONIC,
1405 		     HRTIMER_MODE_REL);
1406 	vcpu->arch.comparecount_timer.function = kvm_mips_comparecount_wakeup;
1407 	return 0;
1408 }
1409 
1410 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
1411 				  struct kvm_translation *tr)
1412 {
1413 	return 0;
1414 }
1415 
1416 /* Initial guest state */
1417 int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
1418 {
1419 	return kvm_mips_callbacks->vcpu_setup(vcpu);
1420 }
1421 
1422 static void kvm_mips_set_c0_status(void)
1423 {
1424 	u32 status = read_c0_status();
1425 
1426 	if (cpu_has_dsp)
1427 		status |= (ST0_MX);
1428 
1429 	write_c0_status(status);
1430 	ehb();
1431 }
1432 
1433 /*
1434  * Return value is in the form (errcode<<2 | RESUME_FLAG_HOST | RESUME_FLAG_NV)
1435  */
1436 int kvm_mips_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu)
1437 {
1438 	u32 cause = vcpu->arch.host_cp0_cause;
1439 	u32 exccode = (cause >> CAUSEB_EXCCODE) & 0x1f;
1440 	u32 __user *opc = (u32 __user *) vcpu->arch.pc;
1441 	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
1442 	enum emulation_result er = EMULATE_DONE;
1443 	int ret = RESUME_GUEST;
1444 
1445 	/* re-enable HTW before enabling interrupts */
1446 	htw_start();
1447 
1448 	/* Set a default exit reason */
1449 	run->exit_reason = KVM_EXIT_UNKNOWN;
1450 	run->ready_for_interrupt_injection = 1;
1451 
1452 	/*
1453 	 * Set the appropriate status bits based on host CPU features,
1454 	 * before we hit the scheduler
1455 	 */
1456 	kvm_mips_set_c0_status();
1457 
1458 	local_irq_enable();
1459 
1460 	kvm_debug("kvm_mips_handle_exit: cause: %#x, PC: %p, kvm_run: %p, kvm_vcpu: %p\n",
1461 			cause, opc, run, vcpu);
1462 	trace_kvm_exit(vcpu, exccode);
1463 
1464 	/*
1465 	 * Do a privilege check, if in UM most of these exit conditions end up
1466 	 * causing an exception to be delivered to the Guest Kernel
1467 	 */
1468 	er = kvm_mips_check_privilege(cause, opc, run, vcpu);
1469 	if (er == EMULATE_PRIV_FAIL) {
1470 		goto skip_emul;
1471 	} else if (er == EMULATE_FAIL) {
1472 		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1473 		ret = RESUME_HOST;
1474 		goto skip_emul;
1475 	}
1476 
1477 	switch (exccode) {
1478 	case EXCCODE_INT:
1479 		kvm_debug("[%d]EXCCODE_INT @ %p\n", vcpu->vcpu_id, opc);
1480 
1481 		++vcpu->stat.int_exits;
1482 
1483 		if (need_resched())
1484 			cond_resched();
1485 
1486 		ret = RESUME_GUEST;
1487 		break;
1488 
1489 	case EXCCODE_CPU:
1490 		kvm_debug("EXCCODE_CPU: @ PC: %p\n", opc);
1491 
1492 		++vcpu->stat.cop_unusable_exits;
1493 		ret = kvm_mips_callbacks->handle_cop_unusable(vcpu);
1494 		/* XXXKYMA: Might need to return to user space */
1495 		if (run->exit_reason == KVM_EXIT_IRQ_WINDOW_OPEN)
1496 			ret = RESUME_HOST;
1497 		break;
1498 
1499 	case EXCCODE_MOD:
1500 		++vcpu->stat.tlbmod_exits;
1501 		ret = kvm_mips_callbacks->handle_tlb_mod(vcpu);
1502 		break;
1503 
1504 	case EXCCODE_TLBS:
1505 		kvm_debug("TLB ST fault:  cause %#x, status %#lx, PC: %p, BadVaddr: %#lx\n",
1506 			  cause, kvm_read_c0_guest_status(vcpu->arch.cop0), opc,
1507 			  badvaddr);
1508 
1509 		++vcpu->stat.tlbmiss_st_exits;
1510 		ret = kvm_mips_callbacks->handle_tlb_st_miss(vcpu);
1511 		break;
1512 
1513 	case EXCCODE_TLBL:
1514 		kvm_debug("TLB LD fault: cause %#x, PC: %p, BadVaddr: %#lx\n",
1515 			  cause, opc, badvaddr);
1516 
1517 		++vcpu->stat.tlbmiss_ld_exits;
1518 		ret = kvm_mips_callbacks->handle_tlb_ld_miss(vcpu);
1519 		break;
1520 
1521 	case EXCCODE_ADES:
1522 		++vcpu->stat.addrerr_st_exits;
1523 		ret = kvm_mips_callbacks->handle_addr_err_st(vcpu);
1524 		break;
1525 
1526 	case EXCCODE_ADEL:
1527 		++vcpu->stat.addrerr_ld_exits;
1528 		ret = kvm_mips_callbacks->handle_addr_err_ld(vcpu);
1529 		break;
1530 
1531 	case EXCCODE_SYS:
1532 		++vcpu->stat.syscall_exits;
1533 		ret = kvm_mips_callbacks->handle_syscall(vcpu);
1534 		break;
1535 
1536 	case EXCCODE_RI:
1537 		++vcpu->stat.resvd_inst_exits;
1538 		ret = kvm_mips_callbacks->handle_res_inst(vcpu);
1539 		break;
1540 
1541 	case EXCCODE_BP:
1542 		++vcpu->stat.break_inst_exits;
1543 		ret = kvm_mips_callbacks->handle_break(vcpu);
1544 		break;
1545 
1546 	case EXCCODE_TR:
1547 		++vcpu->stat.trap_inst_exits;
1548 		ret = kvm_mips_callbacks->handle_trap(vcpu);
1549 		break;
1550 
1551 	case EXCCODE_MSAFPE:
1552 		++vcpu->stat.msa_fpe_exits;
1553 		ret = kvm_mips_callbacks->handle_msa_fpe(vcpu);
1554 		break;
1555 
1556 	case EXCCODE_FPE:
1557 		++vcpu->stat.fpe_exits;
1558 		ret = kvm_mips_callbacks->handle_fpe(vcpu);
1559 		break;
1560 
1561 	case EXCCODE_MSADIS:
1562 		++vcpu->stat.msa_disabled_exits;
1563 		ret = kvm_mips_callbacks->handle_msa_disabled(vcpu);
1564 		break;
1565 
1566 	default:
1567 		kvm_err("Exception Code: %d, not yet handled, @ PC: %p, inst: 0x%08x  BadVaddr: %#lx Status: %#lx\n",
1568 			exccode, opc, kvm_get_inst(opc, vcpu), badvaddr,
1569 			kvm_read_c0_guest_status(vcpu->arch.cop0));
1570 		kvm_arch_vcpu_dump_regs(vcpu);
1571 		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1572 		ret = RESUME_HOST;
1573 		break;
1574 
1575 	}
1576 
1577 skip_emul:
1578 	local_irq_disable();
1579 
1580 	if (er == EMULATE_DONE && !(ret & RESUME_HOST))
1581 		kvm_mips_deliver_interrupts(vcpu, cause);
1582 
1583 	if (!(ret & RESUME_HOST)) {
1584 		/* Only check for signals if not already exiting to userspace */
1585 		if (signal_pending(current)) {
1586 			run->exit_reason = KVM_EXIT_INTR;
1587 			ret = (-EINTR << 2) | RESUME_HOST;
1588 			++vcpu->stat.signal_exits;
1589 			trace_kvm_exit(vcpu, KVM_TRACE_EXIT_SIGNAL);
1590 		}
1591 	}
1592 
1593 	if (ret == RESUME_GUEST) {
1594 		trace_kvm_reenter(vcpu);
1595 
1596 		kvm_mips_check_asids(vcpu);
1597 
1598 		/*
1599 		 * If FPU / MSA are enabled (i.e. the guest's FPU / MSA context
1600 		 * is live), restore FCR31 / MSACSR.
1601 		 *
1602 		 * This should be before returning to the guest exception
1603 		 * vector, as it may well cause an [MSA] FP exception if there
1604 		 * are pending exception bits unmasked. (see
1605 		 * kvm_mips_csr_die_notifier() for how that is handled).
1606 		 */
1607 		if (kvm_mips_guest_has_fpu(&vcpu->arch) &&
1608 		    read_c0_status() & ST0_CU1)
1609 			__kvm_restore_fcsr(&vcpu->arch);
1610 
1611 		if (kvm_mips_guest_has_msa(&vcpu->arch) &&
1612 		    read_c0_config5() & MIPS_CONF5_MSAEN)
1613 			__kvm_restore_msacsr(&vcpu->arch);
1614 	}
1615 
1616 	/* Disable HTW before returning to guest or host */
1617 	htw_stop();
1618 
1619 	return ret;
1620 }
1621 
1622 /* Enable FPU for guest and restore context */
1623 void kvm_own_fpu(struct kvm_vcpu *vcpu)
1624 {
1625 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1626 	unsigned int sr, cfg5;
1627 
1628 	preempt_disable();
1629 
1630 	sr = kvm_read_c0_guest_status(cop0);
1631 
1632 	/*
1633 	 * If MSA state is already live, it is undefined how it interacts with
1634 	 * FR=0 FPU state, and we don't want to hit reserved instruction
1635 	 * exceptions trying to save the MSA state later when CU=1 && FR=1, so
1636 	 * play it safe and save it first.
1637 	 *
1638 	 * In theory we shouldn't ever hit this case since kvm_lose_fpu() should
1639 	 * get called when guest CU1 is set, however we can't trust the guest
1640 	 * not to clobber the status register directly via the commpage.
1641 	 */
1642 	if (cpu_has_msa && sr & ST0_CU1 && !(sr & ST0_FR) &&
1643 	    vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA)
1644 		kvm_lose_fpu(vcpu);
1645 
1646 	/*
1647 	 * Enable FPU for guest
1648 	 * We set FR and FRE according to guest context
1649 	 */
1650 	change_c0_status(ST0_CU1 | ST0_FR, sr);
1651 	if (cpu_has_fre) {
1652 		cfg5 = kvm_read_c0_guest_config5(cop0);
1653 		change_c0_config5(MIPS_CONF5_FRE, cfg5);
1654 	}
1655 	enable_fpu_hazard();
1656 
1657 	/* If guest FPU state not active, restore it now */
1658 	if (!(vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU)) {
1659 		__kvm_restore_fpu(&vcpu->arch);
1660 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1661 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_FPU);
1662 	} else {
1663 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_FPU);
1664 	}
1665 
1666 	preempt_enable();
1667 }
1668 
1669 #ifdef CONFIG_CPU_HAS_MSA
1670 /* Enable MSA for guest and restore context */
1671 void kvm_own_msa(struct kvm_vcpu *vcpu)
1672 {
1673 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1674 	unsigned int sr, cfg5;
1675 
1676 	preempt_disable();
1677 
1678 	/*
1679 	 * Enable FPU if enabled in guest, since we're restoring FPU context
1680 	 * anyway. We set FR and FRE according to guest context.
1681 	 */
1682 	if (kvm_mips_guest_has_fpu(&vcpu->arch)) {
1683 		sr = kvm_read_c0_guest_status(cop0);
1684 
1685 		/*
1686 		 * If FR=0 FPU state is already live, it is undefined how it
1687 		 * interacts with MSA state, so play it safe and save it first.
1688 		 */
1689 		if (!(sr & ST0_FR) &&
1690 		    (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU |
1691 				KVM_MIPS_AUX_MSA)) == KVM_MIPS_AUX_FPU)
1692 			kvm_lose_fpu(vcpu);
1693 
1694 		change_c0_status(ST0_CU1 | ST0_FR, sr);
1695 		if (sr & ST0_CU1 && cpu_has_fre) {
1696 			cfg5 = kvm_read_c0_guest_config5(cop0);
1697 			change_c0_config5(MIPS_CONF5_FRE, cfg5);
1698 		}
1699 	}
1700 
1701 	/* Enable MSA for guest */
1702 	set_c0_config5(MIPS_CONF5_MSAEN);
1703 	enable_fpu_hazard();
1704 
1705 	switch (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA)) {
1706 	case KVM_MIPS_AUX_FPU:
1707 		/*
1708 		 * Guest FPU state already loaded, only restore upper MSA state
1709 		 */
1710 		__kvm_restore_msa_upper(&vcpu->arch);
1711 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1712 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_MSA);
1713 		break;
1714 	case 0:
1715 		/* Neither FPU or MSA already active, restore full MSA state */
1716 		__kvm_restore_msa(&vcpu->arch);
1717 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1718 		if (kvm_mips_guest_has_fpu(&vcpu->arch))
1719 			vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1720 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE,
1721 			      KVM_TRACE_AUX_FPU_MSA);
1722 		break;
1723 	default:
1724 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_MSA);
1725 		break;
1726 	}
1727 
1728 	preempt_enable();
1729 }
1730 #endif
1731 
1732 /* Drop FPU & MSA without saving it */
1733 void kvm_drop_fpu(struct kvm_vcpu *vcpu)
1734 {
1735 	preempt_disable();
1736 	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1737 		disable_msa();
1738 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_MSA);
1739 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_MSA;
1740 	}
1741 	if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1742 		clear_c0_status(ST0_CU1 | ST0_FR);
1743 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_FPU);
1744 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1745 	}
1746 	preempt_enable();
1747 }
1748 
1749 /* Save and disable FPU & MSA */
1750 void kvm_lose_fpu(struct kvm_vcpu *vcpu)
1751 {
1752 	/*
1753 	 * FPU & MSA get disabled in root context (hardware) when it is disabled
1754 	 * in guest context (software), but the register state in the hardware
1755 	 * may still be in use. This is why we explicitly re-enable the hardware
1756 	 * before saving.
1757 	 */
1758 
1759 	preempt_disable();
1760 	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1761 		set_c0_config5(MIPS_CONF5_MSAEN);
1762 		enable_fpu_hazard();
1763 
1764 		__kvm_save_msa(&vcpu->arch);
1765 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU_MSA);
1766 
1767 		/* Disable MSA & FPU */
1768 		disable_msa();
1769 		if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1770 			clear_c0_status(ST0_CU1 | ST0_FR);
1771 			disable_fpu_hazard();
1772 		}
1773 		vcpu->arch.aux_inuse &= ~(KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA);
1774 	} else if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1775 		set_c0_status(ST0_CU1);
1776 		enable_fpu_hazard();
1777 
1778 		__kvm_save_fpu(&vcpu->arch);
1779 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1780 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU);
1781 
1782 		/* Disable FPU */
1783 		clear_c0_status(ST0_CU1 | ST0_FR);
1784 		disable_fpu_hazard();
1785 	}
1786 	preempt_enable();
1787 }
1788 
1789 /*
1790  * Step over a specific ctc1 to FCSR and a specific ctcmsa to MSACSR which are
1791  * used to restore guest FCSR/MSACSR state and may trigger a "harmless" FP/MSAFP
1792  * exception if cause bits are set in the value being written.
1793  */
1794 static int kvm_mips_csr_die_notify(struct notifier_block *self,
1795 				   unsigned long cmd, void *ptr)
1796 {
1797 	struct die_args *args = (struct die_args *)ptr;
1798 	struct pt_regs *regs = args->regs;
1799 	unsigned long pc;
1800 
1801 	/* Only interested in FPE and MSAFPE */
1802 	if (cmd != DIE_FP && cmd != DIE_MSAFP)
1803 		return NOTIFY_DONE;
1804 
1805 	/* Return immediately if guest context isn't active */
1806 	if (!(current->flags & PF_VCPU))
1807 		return NOTIFY_DONE;
1808 
1809 	/* Should never get here from user mode */
1810 	BUG_ON(user_mode(regs));
1811 
1812 	pc = instruction_pointer(regs);
1813 	switch (cmd) {
1814 	case DIE_FP:
1815 		/* match 2nd instruction in __kvm_restore_fcsr */
1816 		if (pc != (unsigned long)&__kvm_restore_fcsr + 4)
1817 			return NOTIFY_DONE;
1818 		break;
1819 	case DIE_MSAFP:
1820 		/* match 2nd/3rd instruction in __kvm_restore_msacsr */
1821 		if (!cpu_has_msa ||
1822 		    pc < (unsigned long)&__kvm_restore_msacsr + 4 ||
1823 		    pc > (unsigned long)&__kvm_restore_msacsr + 8)
1824 			return NOTIFY_DONE;
1825 		break;
1826 	}
1827 
1828 	/* Move PC forward a little and continue executing */
1829 	instruction_pointer(regs) += 4;
1830 
1831 	return NOTIFY_STOP;
1832 }
1833 
1834 static struct notifier_block kvm_mips_csr_die_notifier = {
1835 	.notifier_call = kvm_mips_csr_die_notify,
1836 };
1837 
1838 static int __init kvm_mips_init(void)
1839 {
1840 	int ret;
1841 
1842 	ret = kvm_mips_entry_setup();
1843 	if (ret)
1844 		return ret;
1845 
1846 	ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
1847 
1848 	if (ret)
1849 		return ret;
1850 
1851 	register_die_notifier(&kvm_mips_csr_die_notifier);
1852 
1853 	return 0;
1854 }
1855 
1856 static void __exit kvm_mips_exit(void)
1857 {
1858 	kvm_exit();
1859 
1860 	unregister_die_notifier(&kvm_mips_csr_die_notifier);
1861 }
1862 
1863 module_init(kvm_mips_init);
1864 module_exit(kvm_mips_exit);
1865 
1866 EXPORT_TRACEPOINT_SYMBOL(kvm_exit);
1867