xref: /openbmc/linux/arch/mips/kvm/mips.c (revision f9834f18)
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 
23 #include <asm/fpu.h>
24 #include <asm/page.h>
25 #include <asm/cacheflush.h>
26 #include <asm/mmu_context.h>
27 #include <asm/pgalloc.h>
28 #include <asm/pgtable.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 #define VCPU_STAT(x) offsetof(struct kvm_vcpu, stat.x)
43 struct kvm_stats_debugfs_item debugfs_entries[] = {
44 	{ "wait",	  VCPU_STAT(wait_exits),	 KVM_STAT_VCPU },
45 	{ "cache",	  VCPU_STAT(cache_exits),	 KVM_STAT_VCPU },
46 	{ "signal",	  VCPU_STAT(signal_exits),	 KVM_STAT_VCPU },
47 	{ "interrupt",	  VCPU_STAT(int_exits),		 KVM_STAT_VCPU },
48 	{ "cop_unusable", VCPU_STAT(cop_unusable_exits), KVM_STAT_VCPU },
49 	{ "tlbmod",	  VCPU_STAT(tlbmod_exits),	 KVM_STAT_VCPU },
50 	{ "tlbmiss_ld",	  VCPU_STAT(tlbmiss_ld_exits),	 KVM_STAT_VCPU },
51 	{ "tlbmiss_st",	  VCPU_STAT(tlbmiss_st_exits),	 KVM_STAT_VCPU },
52 	{ "addrerr_st",	  VCPU_STAT(addrerr_st_exits),	 KVM_STAT_VCPU },
53 	{ "addrerr_ld",	  VCPU_STAT(addrerr_ld_exits),	 KVM_STAT_VCPU },
54 	{ "syscall",	  VCPU_STAT(syscall_exits),	 KVM_STAT_VCPU },
55 	{ "resvd_inst",	  VCPU_STAT(resvd_inst_exits),	 KVM_STAT_VCPU },
56 	{ "break_inst",	  VCPU_STAT(break_inst_exits),	 KVM_STAT_VCPU },
57 	{ "trap_inst",	  VCPU_STAT(trap_inst_exits),	 KVM_STAT_VCPU },
58 	{ "msa_fpe",	  VCPU_STAT(msa_fpe_exits),	 KVM_STAT_VCPU },
59 	{ "fpe",	  VCPU_STAT(fpe_exits),		 KVM_STAT_VCPU },
60 	{ "msa_disabled", VCPU_STAT(msa_disabled_exits), KVM_STAT_VCPU },
61 	{ "flush_dcache", VCPU_STAT(flush_dcache_exits), KVM_STAT_VCPU },
62 #ifdef CONFIG_KVM_MIPS_VZ
63 	{ "vz_gpsi",	  VCPU_STAT(vz_gpsi_exits),	 KVM_STAT_VCPU },
64 	{ "vz_gsfc",	  VCPU_STAT(vz_gsfc_exits),	 KVM_STAT_VCPU },
65 	{ "vz_hc",	  VCPU_STAT(vz_hc_exits),	 KVM_STAT_VCPU },
66 	{ "vz_grr",	  VCPU_STAT(vz_grr_exits),	 KVM_STAT_VCPU },
67 	{ "vz_gva",	  VCPU_STAT(vz_gva_exits),	 KVM_STAT_VCPU },
68 	{ "vz_ghfc",	  VCPU_STAT(vz_ghfc_exits),	 KVM_STAT_VCPU },
69 	{ "vz_gpa",	  VCPU_STAT(vz_gpa_exits),	 KVM_STAT_VCPU },
70 	{ "vz_resvd",	  VCPU_STAT(vz_resvd_exits),	 KVM_STAT_VCPU },
71 #endif
72 	{ "halt_successful_poll", VCPU_STAT(halt_successful_poll), KVM_STAT_VCPU },
73 	{ "halt_attempted_poll", VCPU_STAT(halt_attempted_poll), KVM_STAT_VCPU },
74 	{ "halt_poll_invalid", VCPU_STAT(halt_poll_invalid), KVM_STAT_VCPU },
75 	{ "halt_wakeup",  VCPU_STAT(halt_wakeup),	 KVM_STAT_VCPU },
76 	{NULL}
77 };
78 
79 bool kvm_trace_guest_mode_change;
80 
81 int kvm_guest_mode_change_trace_reg(void)
82 {
83 	kvm_trace_guest_mode_change = 1;
84 	return 0;
85 }
86 
87 void kvm_guest_mode_change_trace_unreg(void)
88 {
89 	kvm_trace_guest_mode_change = 0;
90 }
91 
92 /*
93  * XXXKYMA: We are simulatoring a processor that has the WII bit set in
94  * Config7, so we are "runnable" if interrupts are pending
95  */
96 int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
97 {
98 	return !!(vcpu->arch.pending_exceptions);
99 }
100 
101 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
102 {
103 	return false;
104 }
105 
106 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
107 {
108 	return 1;
109 }
110 
111 int kvm_arch_hardware_enable(void)
112 {
113 	return kvm_mips_callbacks->hardware_enable();
114 }
115 
116 void kvm_arch_hardware_disable(void)
117 {
118 	kvm_mips_callbacks->hardware_disable();
119 }
120 
121 int kvm_arch_hardware_setup(void)
122 {
123 	return 0;
124 }
125 
126 int kvm_arch_check_processor_compat(void)
127 {
128 	return 0;
129 }
130 
131 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
132 {
133 	switch (type) {
134 #ifdef CONFIG_KVM_MIPS_VZ
135 	case KVM_VM_MIPS_VZ:
136 #else
137 	case KVM_VM_MIPS_TE:
138 #endif
139 		break;
140 	default:
141 		/* Unsupported KVM type */
142 		return -EINVAL;
143 	};
144 
145 	/* Allocate page table to map GPA -> RPA */
146 	kvm->arch.gpa_mm.pgd = kvm_pgd_alloc();
147 	if (!kvm->arch.gpa_mm.pgd)
148 		return -ENOMEM;
149 
150 	return 0;
151 }
152 
153 void kvm_mips_free_vcpus(struct kvm *kvm)
154 {
155 	unsigned int i;
156 	struct kvm_vcpu *vcpu;
157 
158 	kvm_for_each_vcpu(i, vcpu, kvm) {
159 		kvm_vcpu_destroy(vcpu);
160 	}
161 
162 	mutex_lock(&kvm->lock);
163 
164 	for (i = 0; i < atomic_read(&kvm->online_vcpus); i++)
165 		kvm->vcpus[i] = NULL;
166 
167 	atomic_set(&kvm->online_vcpus, 0);
168 
169 	mutex_unlock(&kvm->lock);
170 }
171 
172 static void kvm_mips_free_gpa_pt(struct kvm *kvm)
173 {
174 	/* It should always be safe to remove after flushing the whole range */
175 	WARN_ON(!kvm_mips_flush_gpa_pt(kvm, 0, ~0));
176 	pgd_free(NULL, kvm->arch.gpa_mm.pgd);
177 }
178 
179 void kvm_arch_destroy_vm(struct kvm *kvm)
180 {
181 	kvm_mips_free_vcpus(kvm);
182 	kvm_mips_free_gpa_pt(kvm);
183 }
184 
185 long kvm_arch_dev_ioctl(struct file *filp, unsigned int ioctl,
186 			unsigned long arg)
187 {
188 	return -ENOIOCTLCMD;
189 }
190 
191 int kvm_arch_create_memslot(struct kvm *kvm, struct kvm_memory_slot *slot,
192 			    unsigned long npages)
193 {
194 	return 0;
195 }
196 
197 void kvm_arch_flush_shadow_all(struct kvm *kvm)
198 {
199 	/* Flush whole GPA */
200 	kvm_mips_flush_gpa_pt(kvm, 0, ~0);
201 
202 	/* Let implementation do the rest */
203 	kvm_mips_callbacks->flush_shadow_all(kvm);
204 }
205 
206 void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
207 				   struct kvm_memory_slot *slot)
208 {
209 	/*
210 	 * The slot has been made invalid (ready for moving or deletion), so we
211 	 * need to ensure that it can no longer be accessed by any guest VCPUs.
212 	 */
213 
214 	spin_lock(&kvm->mmu_lock);
215 	/* Flush slot from GPA */
216 	kvm_mips_flush_gpa_pt(kvm, slot->base_gfn,
217 			      slot->base_gfn + slot->npages - 1);
218 	/* Let implementation do the rest */
219 	kvm_mips_callbacks->flush_shadow_memslot(kvm, slot);
220 	spin_unlock(&kvm->mmu_lock);
221 }
222 
223 int kvm_arch_prepare_memory_region(struct kvm *kvm,
224 				   struct kvm_memory_slot *memslot,
225 				   const struct kvm_userspace_memory_region *mem,
226 				   enum kvm_mr_change change)
227 {
228 	return 0;
229 }
230 
231 void kvm_arch_commit_memory_region(struct kvm *kvm,
232 				   const struct kvm_userspace_memory_region *mem,
233 				   const struct kvm_memory_slot *old,
234 				   const struct kvm_memory_slot *new,
235 				   enum kvm_mr_change change)
236 {
237 	int needs_flush;
238 
239 	kvm_debug("%s: kvm: %p slot: %d, GPA: %llx, size: %llx, QVA: %llx\n",
240 		  __func__, kvm, mem->slot, mem->guest_phys_addr,
241 		  mem->memory_size, mem->userspace_addr);
242 
243 	/*
244 	 * If dirty page logging is enabled, write protect all pages in the slot
245 	 * ready for dirty logging.
246 	 *
247 	 * There is no need to do this in any of the following cases:
248 	 * CREATE:	No dirty mappings will already exist.
249 	 * MOVE/DELETE:	The old mappings will already have been cleaned up by
250 	 *		kvm_arch_flush_shadow_memslot()
251 	 */
252 	if (change == KVM_MR_FLAGS_ONLY &&
253 	    (!(old->flags & KVM_MEM_LOG_DIRTY_PAGES) &&
254 	     new->flags & KVM_MEM_LOG_DIRTY_PAGES)) {
255 		spin_lock(&kvm->mmu_lock);
256 		/* Write protect GPA page table entries */
257 		needs_flush = kvm_mips_mkclean_gpa_pt(kvm, new->base_gfn,
258 					new->base_gfn + new->npages - 1);
259 		/* Let implementation do the rest */
260 		if (needs_flush)
261 			kvm_mips_callbacks->flush_shadow_memslot(kvm, new);
262 		spin_unlock(&kvm->mmu_lock);
263 	}
264 }
265 
266 static inline void dump_handler(const char *symbol, void *start, void *end)
267 {
268 	u32 *p;
269 
270 	pr_debug("LEAF(%s)\n", symbol);
271 
272 	pr_debug("\t.set push\n");
273 	pr_debug("\t.set noreorder\n");
274 
275 	for (p = start; p < (u32 *)end; ++p)
276 		pr_debug("\t.word\t0x%08x\t\t# %p\n", *p, p);
277 
278 	pr_debug("\t.set\tpop\n");
279 
280 	pr_debug("\tEND(%s)\n", symbol);
281 }
282 
283 /* low level hrtimer wake routine */
284 static enum hrtimer_restart kvm_mips_comparecount_wakeup(struct hrtimer *timer)
285 {
286 	struct kvm_vcpu *vcpu;
287 
288 	vcpu = container_of(timer, struct kvm_vcpu, arch.comparecount_timer);
289 
290 	kvm_mips_callbacks->queue_timer_int(vcpu);
291 
292 	vcpu->arch.wait = 0;
293 	if (swq_has_sleeper(&vcpu->wq))
294 		swake_up_one(&vcpu->wq);
295 
296 	return kvm_mips_count_timeout(vcpu);
297 }
298 
299 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
300 {
301 	return 0;
302 }
303 
304 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
305 {
306 	int err, size;
307 	void *gebase, *p, *handler, *refill_start, *refill_end;
308 	int i;
309 
310 	kvm_debug("kvm @ %p: create cpu %d at %p\n",
311 		  vcpu->kvm, vcpu->vcpu_id, vcpu);
312 
313 	err = kvm_mips_callbacks->vcpu_init(vcpu);
314 	if (err)
315 		return err;
316 
317 	hrtimer_init(&vcpu->arch.comparecount_timer, CLOCK_MONOTONIC,
318 		     HRTIMER_MODE_REL);
319 	vcpu->arch.comparecount_timer.function = kvm_mips_comparecount_wakeup;
320 
321 	/*
322 	 * Allocate space for host mode exception handlers that handle
323 	 * guest mode exits
324 	 */
325 	if (cpu_has_veic || cpu_has_vint)
326 		size = 0x200 + VECTORSPACING * 64;
327 	else
328 		size = 0x4000;
329 
330 	gebase = kzalloc(ALIGN(size, PAGE_SIZE), GFP_KERNEL);
331 
332 	if (!gebase) {
333 		err = -ENOMEM;
334 		goto out_uninit_vcpu;
335 	}
336 	kvm_debug("Allocated %d bytes for KVM Exception Handlers @ %p\n",
337 		  ALIGN(size, PAGE_SIZE), gebase);
338 
339 	/*
340 	 * Check new ebase actually fits in CP0_EBase. The lack of a write gate
341 	 * limits us to the low 512MB of physical address space. If the memory
342 	 * we allocate is out of range, just give up now.
343 	 */
344 	if (!cpu_has_ebase_wg && virt_to_phys(gebase) >= 0x20000000) {
345 		kvm_err("CP0_EBase.WG required for guest exception base %pK\n",
346 			gebase);
347 		err = -ENOMEM;
348 		goto out_free_gebase;
349 	}
350 
351 	/* Save new ebase */
352 	vcpu->arch.guest_ebase = gebase;
353 
354 	/* Build guest exception vectors dynamically in unmapped memory */
355 	handler = gebase + 0x2000;
356 
357 	/* TLB refill (or XTLB refill on 64-bit VZ where KX=1) */
358 	refill_start = gebase;
359 	if (IS_ENABLED(CONFIG_KVM_MIPS_VZ) && IS_ENABLED(CONFIG_64BIT))
360 		refill_start += 0x080;
361 	refill_end = kvm_mips_build_tlb_refill_exception(refill_start, handler);
362 
363 	/* General Exception Entry point */
364 	kvm_mips_build_exception(gebase + 0x180, handler);
365 
366 	/* For vectored interrupts poke the exception code @ all offsets 0-7 */
367 	for (i = 0; i < 8; i++) {
368 		kvm_debug("L1 Vectored handler @ %p\n",
369 			  gebase + 0x200 + (i * VECTORSPACING));
370 		kvm_mips_build_exception(gebase + 0x200 + i * VECTORSPACING,
371 					 handler);
372 	}
373 
374 	/* General exit handler */
375 	p = handler;
376 	p = kvm_mips_build_exit(p);
377 
378 	/* Guest entry routine */
379 	vcpu->arch.vcpu_run = p;
380 	p = kvm_mips_build_vcpu_run(p);
381 
382 	/* Dump the generated code */
383 	pr_debug("#include <asm/asm.h>\n");
384 	pr_debug("#include <asm/regdef.h>\n");
385 	pr_debug("\n");
386 	dump_handler("kvm_vcpu_run", vcpu->arch.vcpu_run, p);
387 	dump_handler("kvm_tlb_refill", refill_start, refill_end);
388 	dump_handler("kvm_gen_exc", gebase + 0x180, gebase + 0x200);
389 	dump_handler("kvm_exit", gebase + 0x2000, vcpu->arch.vcpu_run);
390 
391 	/* Invalidate the icache for these ranges */
392 	flush_icache_range((unsigned long)gebase,
393 			   (unsigned long)gebase + ALIGN(size, PAGE_SIZE));
394 
395 	/*
396 	 * Allocate comm page for guest kernel, a TLB will be reserved for
397 	 * mapping GVA @ 0xFFFF8000 to this page
398 	 */
399 	vcpu->arch.kseg0_commpage = kzalloc(PAGE_SIZE << 1, GFP_KERNEL);
400 
401 	if (!vcpu->arch.kseg0_commpage) {
402 		err = -ENOMEM;
403 		goto out_free_gebase;
404 	}
405 
406 	kvm_debug("Allocated COMM page @ %p\n", vcpu->arch.kseg0_commpage);
407 	kvm_mips_commpage_init(vcpu);
408 
409 	/* Init */
410 	vcpu->arch.last_sched_cpu = -1;
411 	vcpu->arch.last_exec_cpu = -1;
412 
413 	/* Initial guest state */
414 	err = kvm_mips_callbacks->vcpu_setup(vcpu);
415 	if (err)
416 		goto out_free_commpage;
417 
418 	return 0;
419 
420 out_free_commpage:
421 	kfree(vcpu->arch.kseg0_commpage);
422 out_free_gebase:
423 	kfree(gebase);
424 out_uninit_vcpu:
425 	kvm_mips_callbacks->vcpu_uninit(vcpu);
426 	return err;
427 }
428 
429 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
430 {
431 	hrtimer_cancel(&vcpu->arch.comparecount_timer);
432 
433 	kvm_mips_dump_stats(vcpu);
434 
435 	kvm_mmu_free_memory_caches(vcpu);
436 	kfree(vcpu->arch.guest_ebase);
437 	kfree(vcpu->arch.kseg0_commpage);
438 
439 	kvm_mips_callbacks->vcpu_uninit(vcpu);
440 }
441 
442 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
443 					struct kvm_guest_debug *dbg)
444 {
445 	return -ENOIOCTLCMD;
446 }
447 
448 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
449 {
450 	int r = -EINTR;
451 
452 	vcpu_load(vcpu);
453 
454 	kvm_sigset_activate(vcpu);
455 
456 	if (vcpu->mmio_needed) {
457 		if (!vcpu->mmio_is_write)
458 			kvm_mips_complete_mmio_load(vcpu, run);
459 		vcpu->mmio_needed = 0;
460 	}
461 
462 	if (run->immediate_exit)
463 		goto out;
464 
465 	lose_fpu(1);
466 
467 	local_irq_disable();
468 	guest_enter_irqoff();
469 	trace_kvm_enter(vcpu);
470 
471 	/*
472 	 * Make sure the read of VCPU requests in vcpu_run() callback is not
473 	 * reordered ahead of the write to vcpu->mode, or we could miss a TLB
474 	 * flush request while the requester sees the VCPU as outside of guest
475 	 * mode and not needing an IPI.
476 	 */
477 	smp_store_mb(vcpu->mode, IN_GUEST_MODE);
478 
479 	r = kvm_mips_callbacks->vcpu_run(run, vcpu);
480 
481 	trace_kvm_out(vcpu);
482 	guest_exit_irqoff();
483 	local_irq_enable();
484 
485 out:
486 	kvm_sigset_deactivate(vcpu);
487 
488 	vcpu_put(vcpu);
489 	return r;
490 }
491 
492 int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
493 			     struct kvm_mips_interrupt *irq)
494 {
495 	int intr = (int)irq->irq;
496 	struct kvm_vcpu *dvcpu = NULL;
497 
498 	if (intr == 3 || intr == -3 || intr == 4 || intr == -4)
499 		kvm_debug("%s: CPU: %d, INTR: %d\n", __func__, irq->cpu,
500 			  (int)intr);
501 
502 	if (irq->cpu == -1)
503 		dvcpu = vcpu;
504 	else
505 		dvcpu = vcpu->kvm->vcpus[irq->cpu];
506 
507 	if (intr == 2 || intr == 3 || intr == 4) {
508 		kvm_mips_callbacks->queue_io_int(dvcpu, irq);
509 
510 	} else if (intr == -2 || intr == -3 || intr == -4) {
511 		kvm_mips_callbacks->dequeue_io_int(dvcpu, irq);
512 	} else {
513 		kvm_err("%s: invalid interrupt ioctl (%d:%d)\n", __func__,
514 			irq->cpu, irq->irq);
515 		return -EINVAL;
516 	}
517 
518 	dvcpu->arch.wait = 0;
519 
520 	if (swq_has_sleeper(&dvcpu->wq))
521 		swake_up_one(&dvcpu->wq);
522 
523 	return 0;
524 }
525 
526 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
527 				    struct kvm_mp_state *mp_state)
528 {
529 	return -ENOIOCTLCMD;
530 }
531 
532 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
533 				    struct kvm_mp_state *mp_state)
534 {
535 	return -ENOIOCTLCMD;
536 }
537 
538 static u64 kvm_mips_get_one_regs[] = {
539 	KVM_REG_MIPS_R0,
540 	KVM_REG_MIPS_R1,
541 	KVM_REG_MIPS_R2,
542 	KVM_REG_MIPS_R3,
543 	KVM_REG_MIPS_R4,
544 	KVM_REG_MIPS_R5,
545 	KVM_REG_MIPS_R6,
546 	KVM_REG_MIPS_R7,
547 	KVM_REG_MIPS_R8,
548 	KVM_REG_MIPS_R9,
549 	KVM_REG_MIPS_R10,
550 	KVM_REG_MIPS_R11,
551 	KVM_REG_MIPS_R12,
552 	KVM_REG_MIPS_R13,
553 	KVM_REG_MIPS_R14,
554 	KVM_REG_MIPS_R15,
555 	KVM_REG_MIPS_R16,
556 	KVM_REG_MIPS_R17,
557 	KVM_REG_MIPS_R18,
558 	KVM_REG_MIPS_R19,
559 	KVM_REG_MIPS_R20,
560 	KVM_REG_MIPS_R21,
561 	KVM_REG_MIPS_R22,
562 	KVM_REG_MIPS_R23,
563 	KVM_REG_MIPS_R24,
564 	KVM_REG_MIPS_R25,
565 	KVM_REG_MIPS_R26,
566 	KVM_REG_MIPS_R27,
567 	KVM_REG_MIPS_R28,
568 	KVM_REG_MIPS_R29,
569 	KVM_REG_MIPS_R30,
570 	KVM_REG_MIPS_R31,
571 
572 #ifndef CONFIG_CPU_MIPSR6
573 	KVM_REG_MIPS_HI,
574 	KVM_REG_MIPS_LO,
575 #endif
576 	KVM_REG_MIPS_PC,
577 };
578 
579 static u64 kvm_mips_get_one_regs_fpu[] = {
580 	KVM_REG_MIPS_FCR_IR,
581 	KVM_REG_MIPS_FCR_CSR,
582 };
583 
584 static u64 kvm_mips_get_one_regs_msa[] = {
585 	KVM_REG_MIPS_MSA_IR,
586 	KVM_REG_MIPS_MSA_CSR,
587 };
588 
589 static unsigned long kvm_mips_num_regs(struct kvm_vcpu *vcpu)
590 {
591 	unsigned long ret;
592 
593 	ret = ARRAY_SIZE(kvm_mips_get_one_regs);
594 	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
595 		ret += ARRAY_SIZE(kvm_mips_get_one_regs_fpu) + 48;
596 		/* odd doubles */
597 		if (boot_cpu_data.fpu_id & MIPS_FPIR_F64)
598 			ret += 16;
599 	}
600 	if (kvm_mips_guest_can_have_msa(&vcpu->arch))
601 		ret += ARRAY_SIZE(kvm_mips_get_one_regs_msa) + 32;
602 	ret += kvm_mips_callbacks->num_regs(vcpu);
603 
604 	return ret;
605 }
606 
607 static int kvm_mips_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices)
608 {
609 	u64 index;
610 	unsigned int i;
611 
612 	if (copy_to_user(indices, kvm_mips_get_one_regs,
613 			 sizeof(kvm_mips_get_one_regs)))
614 		return -EFAULT;
615 	indices += ARRAY_SIZE(kvm_mips_get_one_regs);
616 
617 	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
618 		if (copy_to_user(indices, kvm_mips_get_one_regs_fpu,
619 				 sizeof(kvm_mips_get_one_regs_fpu)))
620 			return -EFAULT;
621 		indices += ARRAY_SIZE(kvm_mips_get_one_regs_fpu);
622 
623 		for (i = 0; i < 32; ++i) {
624 			index = KVM_REG_MIPS_FPR_32(i);
625 			if (copy_to_user(indices, &index, sizeof(index)))
626 				return -EFAULT;
627 			++indices;
628 
629 			/* skip odd doubles if no F64 */
630 			if (i & 1 && !(boot_cpu_data.fpu_id & MIPS_FPIR_F64))
631 				continue;
632 
633 			index = KVM_REG_MIPS_FPR_64(i);
634 			if (copy_to_user(indices, &index, sizeof(index)))
635 				return -EFAULT;
636 			++indices;
637 		}
638 	}
639 
640 	if (kvm_mips_guest_can_have_msa(&vcpu->arch)) {
641 		if (copy_to_user(indices, kvm_mips_get_one_regs_msa,
642 				 sizeof(kvm_mips_get_one_regs_msa)))
643 			return -EFAULT;
644 		indices += ARRAY_SIZE(kvm_mips_get_one_regs_msa);
645 
646 		for (i = 0; i < 32; ++i) {
647 			index = KVM_REG_MIPS_VEC_128(i);
648 			if (copy_to_user(indices, &index, sizeof(index)))
649 				return -EFAULT;
650 			++indices;
651 		}
652 	}
653 
654 	return kvm_mips_callbacks->copy_reg_indices(vcpu, indices);
655 }
656 
657 static int kvm_mips_get_reg(struct kvm_vcpu *vcpu,
658 			    const struct kvm_one_reg *reg)
659 {
660 	struct mips_coproc *cop0 = vcpu->arch.cop0;
661 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
662 	int ret;
663 	s64 v;
664 	s64 vs[2];
665 	unsigned int idx;
666 
667 	switch (reg->id) {
668 	/* General purpose registers */
669 	case KVM_REG_MIPS_R0 ... KVM_REG_MIPS_R31:
670 		v = (long)vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0];
671 		break;
672 #ifndef CONFIG_CPU_MIPSR6
673 	case KVM_REG_MIPS_HI:
674 		v = (long)vcpu->arch.hi;
675 		break;
676 	case KVM_REG_MIPS_LO:
677 		v = (long)vcpu->arch.lo;
678 		break;
679 #endif
680 	case KVM_REG_MIPS_PC:
681 		v = (long)vcpu->arch.pc;
682 		break;
683 
684 	/* Floating point registers */
685 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
686 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
687 			return -EINVAL;
688 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
689 		/* Odd singles in top of even double when FR=0 */
690 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
691 			v = get_fpr32(&fpu->fpr[idx], 0);
692 		else
693 			v = get_fpr32(&fpu->fpr[idx & ~1], idx & 1);
694 		break;
695 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
696 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
697 			return -EINVAL;
698 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
699 		/* Can't access odd doubles in FR=0 mode */
700 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
701 			return -EINVAL;
702 		v = get_fpr64(&fpu->fpr[idx], 0);
703 		break;
704 	case KVM_REG_MIPS_FCR_IR:
705 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
706 			return -EINVAL;
707 		v = boot_cpu_data.fpu_id;
708 		break;
709 	case KVM_REG_MIPS_FCR_CSR:
710 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
711 			return -EINVAL;
712 		v = fpu->fcr31;
713 		break;
714 
715 	/* MIPS SIMD Architecture (MSA) registers */
716 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
717 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
718 			return -EINVAL;
719 		/* Can't access MSA registers in FR=0 mode */
720 		if (!(kvm_read_c0_guest_status(cop0) & ST0_FR))
721 			return -EINVAL;
722 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
723 #ifdef CONFIG_CPU_LITTLE_ENDIAN
724 		/* least significant byte first */
725 		vs[0] = get_fpr64(&fpu->fpr[idx], 0);
726 		vs[1] = get_fpr64(&fpu->fpr[idx], 1);
727 #else
728 		/* most significant byte first */
729 		vs[0] = get_fpr64(&fpu->fpr[idx], 1);
730 		vs[1] = get_fpr64(&fpu->fpr[idx], 0);
731 #endif
732 		break;
733 	case KVM_REG_MIPS_MSA_IR:
734 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
735 			return -EINVAL;
736 		v = boot_cpu_data.msa_id;
737 		break;
738 	case KVM_REG_MIPS_MSA_CSR:
739 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
740 			return -EINVAL;
741 		v = fpu->msacsr;
742 		break;
743 
744 	/* registers to be handled specially */
745 	default:
746 		ret = kvm_mips_callbacks->get_one_reg(vcpu, reg, &v);
747 		if (ret)
748 			return ret;
749 		break;
750 	}
751 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
752 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
753 
754 		return put_user(v, uaddr64);
755 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
756 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
757 		u32 v32 = (u32)v;
758 
759 		return put_user(v32, uaddr32);
760 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
761 		void __user *uaddr = (void __user *)(long)reg->addr;
762 
763 		return copy_to_user(uaddr, vs, 16) ? -EFAULT : 0;
764 	} else {
765 		return -EINVAL;
766 	}
767 }
768 
769 static int kvm_mips_set_reg(struct kvm_vcpu *vcpu,
770 			    const struct kvm_one_reg *reg)
771 {
772 	struct mips_coproc *cop0 = vcpu->arch.cop0;
773 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
774 	s64 v;
775 	s64 vs[2];
776 	unsigned int idx;
777 
778 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
779 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
780 
781 		if (get_user(v, uaddr64) != 0)
782 			return -EFAULT;
783 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
784 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
785 		s32 v32;
786 
787 		if (get_user(v32, uaddr32) != 0)
788 			return -EFAULT;
789 		v = (s64)v32;
790 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
791 		void __user *uaddr = (void __user *)(long)reg->addr;
792 
793 		return copy_from_user(vs, uaddr, 16) ? -EFAULT : 0;
794 	} else {
795 		return -EINVAL;
796 	}
797 
798 	switch (reg->id) {
799 	/* General purpose registers */
800 	case KVM_REG_MIPS_R0:
801 		/* Silently ignore requests to set $0 */
802 		break;
803 	case KVM_REG_MIPS_R1 ... KVM_REG_MIPS_R31:
804 		vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0] = v;
805 		break;
806 #ifndef CONFIG_CPU_MIPSR6
807 	case KVM_REG_MIPS_HI:
808 		vcpu->arch.hi = v;
809 		break;
810 	case KVM_REG_MIPS_LO:
811 		vcpu->arch.lo = v;
812 		break;
813 #endif
814 	case KVM_REG_MIPS_PC:
815 		vcpu->arch.pc = v;
816 		break;
817 
818 	/* Floating point registers */
819 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
820 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
821 			return -EINVAL;
822 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
823 		/* Odd singles in top of even double when FR=0 */
824 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
825 			set_fpr32(&fpu->fpr[idx], 0, v);
826 		else
827 			set_fpr32(&fpu->fpr[idx & ~1], idx & 1, v);
828 		break;
829 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
830 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
831 			return -EINVAL;
832 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
833 		/* Can't access odd doubles in FR=0 mode */
834 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
835 			return -EINVAL;
836 		set_fpr64(&fpu->fpr[idx], 0, v);
837 		break;
838 	case KVM_REG_MIPS_FCR_IR:
839 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
840 			return -EINVAL;
841 		/* Read-only */
842 		break;
843 	case KVM_REG_MIPS_FCR_CSR:
844 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
845 			return -EINVAL;
846 		fpu->fcr31 = v;
847 		break;
848 
849 	/* MIPS SIMD Architecture (MSA) registers */
850 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
851 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
852 			return -EINVAL;
853 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
854 #ifdef CONFIG_CPU_LITTLE_ENDIAN
855 		/* least significant byte first */
856 		set_fpr64(&fpu->fpr[idx], 0, vs[0]);
857 		set_fpr64(&fpu->fpr[idx], 1, vs[1]);
858 #else
859 		/* most significant byte first */
860 		set_fpr64(&fpu->fpr[idx], 1, vs[0]);
861 		set_fpr64(&fpu->fpr[idx], 0, vs[1]);
862 #endif
863 		break;
864 	case KVM_REG_MIPS_MSA_IR:
865 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
866 			return -EINVAL;
867 		/* Read-only */
868 		break;
869 	case KVM_REG_MIPS_MSA_CSR:
870 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
871 			return -EINVAL;
872 		fpu->msacsr = v;
873 		break;
874 
875 	/* registers to be handled specially */
876 	default:
877 		return kvm_mips_callbacks->set_one_reg(vcpu, reg, v);
878 	}
879 	return 0;
880 }
881 
882 static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
883 				     struct kvm_enable_cap *cap)
884 {
885 	int r = 0;
886 
887 	if (!kvm_vm_ioctl_check_extension(vcpu->kvm, cap->cap))
888 		return -EINVAL;
889 	if (cap->flags)
890 		return -EINVAL;
891 	if (cap->args[0])
892 		return -EINVAL;
893 
894 	switch (cap->cap) {
895 	case KVM_CAP_MIPS_FPU:
896 		vcpu->arch.fpu_enabled = true;
897 		break;
898 	case KVM_CAP_MIPS_MSA:
899 		vcpu->arch.msa_enabled = true;
900 		break;
901 	default:
902 		r = -EINVAL;
903 		break;
904 	}
905 
906 	return r;
907 }
908 
909 long kvm_arch_vcpu_async_ioctl(struct file *filp, unsigned int ioctl,
910 			       unsigned long arg)
911 {
912 	struct kvm_vcpu *vcpu = filp->private_data;
913 	void __user *argp = (void __user *)arg;
914 
915 	if (ioctl == KVM_INTERRUPT) {
916 		struct kvm_mips_interrupt irq;
917 
918 		if (copy_from_user(&irq, argp, sizeof(irq)))
919 			return -EFAULT;
920 		kvm_debug("[%d] %s: irq: %d\n", vcpu->vcpu_id, __func__,
921 			  irq.irq);
922 
923 		return kvm_vcpu_ioctl_interrupt(vcpu, &irq);
924 	}
925 
926 	return -ENOIOCTLCMD;
927 }
928 
929 long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl,
930 			 unsigned long arg)
931 {
932 	struct kvm_vcpu *vcpu = filp->private_data;
933 	void __user *argp = (void __user *)arg;
934 	long r;
935 
936 	vcpu_load(vcpu);
937 
938 	switch (ioctl) {
939 	case KVM_SET_ONE_REG:
940 	case KVM_GET_ONE_REG: {
941 		struct kvm_one_reg reg;
942 
943 		r = -EFAULT;
944 		if (copy_from_user(&reg, argp, sizeof(reg)))
945 			break;
946 		if (ioctl == KVM_SET_ONE_REG)
947 			r = kvm_mips_set_reg(vcpu, &reg);
948 		else
949 			r = kvm_mips_get_reg(vcpu, &reg);
950 		break;
951 	}
952 	case KVM_GET_REG_LIST: {
953 		struct kvm_reg_list __user *user_list = argp;
954 		struct kvm_reg_list reg_list;
955 		unsigned n;
956 
957 		r = -EFAULT;
958 		if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
959 			break;
960 		n = reg_list.n;
961 		reg_list.n = kvm_mips_num_regs(vcpu);
962 		if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
963 			break;
964 		r = -E2BIG;
965 		if (n < reg_list.n)
966 			break;
967 		r = kvm_mips_copy_reg_indices(vcpu, user_list->reg);
968 		break;
969 	}
970 	case KVM_ENABLE_CAP: {
971 		struct kvm_enable_cap cap;
972 
973 		r = -EFAULT;
974 		if (copy_from_user(&cap, argp, sizeof(cap)))
975 			break;
976 		r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
977 		break;
978 	}
979 	default:
980 		r = -ENOIOCTLCMD;
981 	}
982 
983 	vcpu_put(vcpu);
984 	return r;
985 }
986 
987 /**
988  * kvm_vm_ioctl_get_dirty_log - get and clear the log of dirty pages in a slot
989  * @kvm: kvm instance
990  * @log: slot id and address to which we copy the log
991  *
992  * Steps 1-4 below provide general overview of dirty page logging. See
993  * kvm_get_dirty_log_protect() function description for additional details.
994  *
995  * We call kvm_get_dirty_log_protect() to handle steps 1-3, upon return we
996  * always flush the TLB (step 4) even if previous step failed  and the dirty
997  * bitmap may be corrupt. Regardless of previous outcome the KVM logging API
998  * does not preclude user space subsequent dirty log read. Flushing TLB ensures
999  * writes will be marked dirty for next log read.
1000  *
1001  *   1. Take a snapshot of the bit and clear it if needed.
1002  *   2. Write protect the corresponding page.
1003  *   3. Copy the snapshot to the userspace.
1004  *   4. Flush TLB's if needed.
1005  */
1006 int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log)
1007 {
1008 	struct kvm_memslots *slots;
1009 	struct kvm_memory_slot *memslot;
1010 	bool flush = false;
1011 	int r;
1012 
1013 	mutex_lock(&kvm->slots_lock);
1014 
1015 	r = kvm_get_dirty_log_protect(kvm, log, &flush);
1016 
1017 	if (flush) {
1018 		slots = kvm_memslots(kvm);
1019 		memslot = id_to_memslot(slots, log->slot);
1020 
1021 		/* Let implementation handle TLB/GVA invalidation */
1022 		kvm_mips_callbacks->flush_shadow_memslot(kvm, memslot);
1023 	}
1024 
1025 	mutex_unlock(&kvm->slots_lock);
1026 	return r;
1027 }
1028 
1029 int kvm_vm_ioctl_clear_dirty_log(struct kvm *kvm, struct kvm_clear_dirty_log *log)
1030 {
1031 	struct kvm_memslots *slots;
1032 	struct kvm_memory_slot *memslot;
1033 	bool flush = false;
1034 	int r;
1035 
1036 	mutex_lock(&kvm->slots_lock);
1037 
1038 	r = kvm_clear_dirty_log_protect(kvm, log, &flush);
1039 
1040 	if (flush) {
1041 		slots = kvm_memslots(kvm);
1042 		memslot = id_to_memslot(slots, log->slot);
1043 
1044 		/* Let implementation handle TLB/GVA invalidation */
1045 		kvm_mips_callbacks->flush_shadow_memslot(kvm, memslot);
1046 	}
1047 
1048 	mutex_unlock(&kvm->slots_lock);
1049 	return r;
1050 }
1051 
1052 long kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
1053 {
1054 	long r;
1055 
1056 	switch (ioctl) {
1057 	default:
1058 		r = -ENOIOCTLCMD;
1059 	}
1060 
1061 	return r;
1062 }
1063 
1064 int kvm_arch_init(void *opaque)
1065 {
1066 	if (kvm_mips_callbacks) {
1067 		kvm_err("kvm: module already exists\n");
1068 		return -EEXIST;
1069 	}
1070 
1071 	return kvm_mips_emulation_init(&kvm_mips_callbacks);
1072 }
1073 
1074 void kvm_arch_exit(void)
1075 {
1076 	kvm_mips_callbacks = NULL;
1077 }
1078 
1079 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
1080 				  struct kvm_sregs *sregs)
1081 {
1082 	return -ENOIOCTLCMD;
1083 }
1084 
1085 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
1086 				  struct kvm_sregs *sregs)
1087 {
1088 	return -ENOIOCTLCMD;
1089 }
1090 
1091 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
1092 {
1093 }
1094 
1095 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1096 {
1097 	return -ENOIOCTLCMD;
1098 }
1099 
1100 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1101 {
1102 	return -ENOIOCTLCMD;
1103 }
1104 
1105 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
1106 {
1107 	return VM_FAULT_SIGBUS;
1108 }
1109 
1110 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
1111 {
1112 	int r;
1113 
1114 	switch (ext) {
1115 	case KVM_CAP_ONE_REG:
1116 	case KVM_CAP_ENABLE_CAP:
1117 	case KVM_CAP_READONLY_MEM:
1118 	case KVM_CAP_SYNC_MMU:
1119 	case KVM_CAP_IMMEDIATE_EXIT:
1120 		r = 1;
1121 		break;
1122 	case KVM_CAP_NR_VCPUS:
1123 		r = num_online_cpus();
1124 		break;
1125 	case KVM_CAP_MAX_VCPUS:
1126 		r = KVM_MAX_VCPUS;
1127 		break;
1128 	case KVM_CAP_MAX_VCPU_ID:
1129 		r = KVM_MAX_VCPU_ID;
1130 		break;
1131 	case KVM_CAP_MIPS_FPU:
1132 		/* We don't handle systems with inconsistent cpu_has_fpu */
1133 		r = !!raw_cpu_has_fpu;
1134 		break;
1135 	case KVM_CAP_MIPS_MSA:
1136 		/*
1137 		 * We don't support MSA vector partitioning yet:
1138 		 * 1) It would require explicit support which can't be tested
1139 		 *    yet due to lack of support in current hardware.
1140 		 * 2) It extends the state that would need to be saved/restored
1141 		 *    by e.g. QEMU for migration.
1142 		 *
1143 		 * When vector partitioning hardware becomes available, support
1144 		 * could be added by requiring a flag when enabling
1145 		 * KVM_CAP_MIPS_MSA capability to indicate that userland knows
1146 		 * to save/restore the appropriate extra state.
1147 		 */
1148 		r = cpu_has_msa && !(boot_cpu_data.msa_id & MSA_IR_WRPF);
1149 		break;
1150 	default:
1151 		r = kvm_mips_callbacks->check_extension(kvm, ext);
1152 		break;
1153 	}
1154 	return r;
1155 }
1156 
1157 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
1158 {
1159 	return kvm_mips_pending_timer(vcpu) ||
1160 		kvm_read_c0_guest_cause(vcpu->arch.cop0) & C_TI;
1161 }
1162 
1163 int kvm_arch_vcpu_dump_regs(struct kvm_vcpu *vcpu)
1164 {
1165 	int i;
1166 	struct mips_coproc *cop0;
1167 
1168 	if (!vcpu)
1169 		return -1;
1170 
1171 	kvm_debug("VCPU Register Dump:\n");
1172 	kvm_debug("\tpc = 0x%08lx\n", vcpu->arch.pc);
1173 	kvm_debug("\texceptions: %08lx\n", vcpu->arch.pending_exceptions);
1174 
1175 	for (i = 0; i < 32; i += 4) {
1176 		kvm_debug("\tgpr%02d: %08lx %08lx %08lx %08lx\n", i,
1177 		       vcpu->arch.gprs[i],
1178 		       vcpu->arch.gprs[i + 1],
1179 		       vcpu->arch.gprs[i + 2], vcpu->arch.gprs[i + 3]);
1180 	}
1181 	kvm_debug("\thi: 0x%08lx\n", vcpu->arch.hi);
1182 	kvm_debug("\tlo: 0x%08lx\n", vcpu->arch.lo);
1183 
1184 	cop0 = vcpu->arch.cop0;
1185 	kvm_debug("\tStatus: 0x%08x, Cause: 0x%08x\n",
1186 		  kvm_read_c0_guest_status(cop0),
1187 		  kvm_read_c0_guest_cause(cop0));
1188 
1189 	kvm_debug("\tEPC: 0x%08lx\n", kvm_read_c0_guest_epc(cop0));
1190 
1191 	return 0;
1192 }
1193 
1194 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1195 {
1196 	int i;
1197 
1198 	vcpu_load(vcpu);
1199 
1200 	for (i = 1; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1201 		vcpu->arch.gprs[i] = regs->gpr[i];
1202 	vcpu->arch.gprs[0] = 0; /* zero is special, and cannot be set. */
1203 	vcpu->arch.hi = regs->hi;
1204 	vcpu->arch.lo = regs->lo;
1205 	vcpu->arch.pc = regs->pc;
1206 
1207 	vcpu_put(vcpu);
1208 	return 0;
1209 }
1210 
1211 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1212 {
1213 	int i;
1214 
1215 	vcpu_load(vcpu);
1216 
1217 	for (i = 0; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1218 		regs->gpr[i] = vcpu->arch.gprs[i];
1219 
1220 	regs->hi = vcpu->arch.hi;
1221 	regs->lo = vcpu->arch.lo;
1222 	regs->pc = vcpu->arch.pc;
1223 
1224 	vcpu_put(vcpu);
1225 	return 0;
1226 }
1227 
1228 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
1229 				  struct kvm_translation *tr)
1230 {
1231 	return 0;
1232 }
1233 
1234 static void kvm_mips_set_c0_status(void)
1235 {
1236 	u32 status = read_c0_status();
1237 
1238 	if (cpu_has_dsp)
1239 		status |= (ST0_MX);
1240 
1241 	write_c0_status(status);
1242 	ehb();
1243 }
1244 
1245 /*
1246  * Return value is in the form (errcode<<2 | RESUME_FLAG_HOST | RESUME_FLAG_NV)
1247  */
1248 int kvm_mips_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu)
1249 {
1250 	u32 cause = vcpu->arch.host_cp0_cause;
1251 	u32 exccode = (cause >> CAUSEB_EXCCODE) & 0x1f;
1252 	u32 __user *opc = (u32 __user *) vcpu->arch.pc;
1253 	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
1254 	enum emulation_result er = EMULATE_DONE;
1255 	u32 inst;
1256 	int ret = RESUME_GUEST;
1257 
1258 	vcpu->mode = OUTSIDE_GUEST_MODE;
1259 
1260 	/* re-enable HTW before enabling interrupts */
1261 	if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ))
1262 		htw_start();
1263 
1264 	/* Set a default exit reason */
1265 	run->exit_reason = KVM_EXIT_UNKNOWN;
1266 	run->ready_for_interrupt_injection = 1;
1267 
1268 	/*
1269 	 * Set the appropriate status bits based on host CPU features,
1270 	 * before we hit the scheduler
1271 	 */
1272 	kvm_mips_set_c0_status();
1273 
1274 	local_irq_enable();
1275 
1276 	kvm_debug("kvm_mips_handle_exit: cause: %#x, PC: %p, kvm_run: %p, kvm_vcpu: %p\n",
1277 			cause, opc, run, vcpu);
1278 	trace_kvm_exit(vcpu, exccode);
1279 
1280 	if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) {
1281 		/*
1282 		 * Do a privilege check, if in UM most of these exit conditions
1283 		 * end up causing an exception to be delivered to the Guest
1284 		 * Kernel
1285 		 */
1286 		er = kvm_mips_check_privilege(cause, opc, run, vcpu);
1287 		if (er == EMULATE_PRIV_FAIL) {
1288 			goto skip_emul;
1289 		} else if (er == EMULATE_FAIL) {
1290 			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1291 			ret = RESUME_HOST;
1292 			goto skip_emul;
1293 		}
1294 	}
1295 
1296 	switch (exccode) {
1297 	case EXCCODE_INT:
1298 		kvm_debug("[%d]EXCCODE_INT @ %p\n", vcpu->vcpu_id, opc);
1299 
1300 		++vcpu->stat.int_exits;
1301 
1302 		if (need_resched())
1303 			cond_resched();
1304 
1305 		ret = RESUME_GUEST;
1306 		break;
1307 
1308 	case EXCCODE_CPU:
1309 		kvm_debug("EXCCODE_CPU: @ PC: %p\n", opc);
1310 
1311 		++vcpu->stat.cop_unusable_exits;
1312 		ret = kvm_mips_callbacks->handle_cop_unusable(vcpu);
1313 		/* XXXKYMA: Might need to return to user space */
1314 		if (run->exit_reason == KVM_EXIT_IRQ_WINDOW_OPEN)
1315 			ret = RESUME_HOST;
1316 		break;
1317 
1318 	case EXCCODE_MOD:
1319 		++vcpu->stat.tlbmod_exits;
1320 		ret = kvm_mips_callbacks->handle_tlb_mod(vcpu);
1321 		break;
1322 
1323 	case EXCCODE_TLBS:
1324 		kvm_debug("TLB ST fault:  cause %#x, status %#x, PC: %p, BadVaddr: %#lx\n",
1325 			  cause, kvm_read_c0_guest_status(vcpu->arch.cop0), opc,
1326 			  badvaddr);
1327 
1328 		++vcpu->stat.tlbmiss_st_exits;
1329 		ret = kvm_mips_callbacks->handle_tlb_st_miss(vcpu);
1330 		break;
1331 
1332 	case EXCCODE_TLBL:
1333 		kvm_debug("TLB LD fault: cause %#x, PC: %p, BadVaddr: %#lx\n",
1334 			  cause, opc, badvaddr);
1335 
1336 		++vcpu->stat.tlbmiss_ld_exits;
1337 		ret = kvm_mips_callbacks->handle_tlb_ld_miss(vcpu);
1338 		break;
1339 
1340 	case EXCCODE_ADES:
1341 		++vcpu->stat.addrerr_st_exits;
1342 		ret = kvm_mips_callbacks->handle_addr_err_st(vcpu);
1343 		break;
1344 
1345 	case EXCCODE_ADEL:
1346 		++vcpu->stat.addrerr_ld_exits;
1347 		ret = kvm_mips_callbacks->handle_addr_err_ld(vcpu);
1348 		break;
1349 
1350 	case EXCCODE_SYS:
1351 		++vcpu->stat.syscall_exits;
1352 		ret = kvm_mips_callbacks->handle_syscall(vcpu);
1353 		break;
1354 
1355 	case EXCCODE_RI:
1356 		++vcpu->stat.resvd_inst_exits;
1357 		ret = kvm_mips_callbacks->handle_res_inst(vcpu);
1358 		break;
1359 
1360 	case EXCCODE_BP:
1361 		++vcpu->stat.break_inst_exits;
1362 		ret = kvm_mips_callbacks->handle_break(vcpu);
1363 		break;
1364 
1365 	case EXCCODE_TR:
1366 		++vcpu->stat.trap_inst_exits;
1367 		ret = kvm_mips_callbacks->handle_trap(vcpu);
1368 		break;
1369 
1370 	case EXCCODE_MSAFPE:
1371 		++vcpu->stat.msa_fpe_exits;
1372 		ret = kvm_mips_callbacks->handle_msa_fpe(vcpu);
1373 		break;
1374 
1375 	case EXCCODE_FPE:
1376 		++vcpu->stat.fpe_exits;
1377 		ret = kvm_mips_callbacks->handle_fpe(vcpu);
1378 		break;
1379 
1380 	case EXCCODE_MSADIS:
1381 		++vcpu->stat.msa_disabled_exits;
1382 		ret = kvm_mips_callbacks->handle_msa_disabled(vcpu);
1383 		break;
1384 
1385 	case EXCCODE_GE:
1386 		/* defer exit accounting to handler */
1387 		ret = kvm_mips_callbacks->handle_guest_exit(vcpu);
1388 		break;
1389 
1390 	default:
1391 		if (cause & CAUSEF_BD)
1392 			opc += 1;
1393 		inst = 0;
1394 		kvm_get_badinstr(opc, vcpu, &inst);
1395 		kvm_err("Exception Code: %d, not yet handled, @ PC: %p, inst: 0x%08x  BadVaddr: %#lx Status: %#x\n",
1396 			exccode, opc, inst, badvaddr,
1397 			kvm_read_c0_guest_status(vcpu->arch.cop0));
1398 		kvm_arch_vcpu_dump_regs(vcpu);
1399 		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1400 		ret = RESUME_HOST;
1401 		break;
1402 
1403 	}
1404 
1405 skip_emul:
1406 	local_irq_disable();
1407 
1408 	if (ret == RESUME_GUEST)
1409 		kvm_vz_acquire_htimer(vcpu);
1410 
1411 	if (er == EMULATE_DONE && !(ret & RESUME_HOST))
1412 		kvm_mips_deliver_interrupts(vcpu, cause);
1413 
1414 	if (!(ret & RESUME_HOST)) {
1415 		/* Only check for signals if not already exiting to userspace */
1416 		if (signal_pending(current)) {
1417 			run->exit_reason = KVM_EXIT_INTR;
1418 			ret = (-EINTR << 2) | RESUME_HOST;
1419 			++vcpu->stat.signal_exits;
1420 			trace_kvm_exit(vcpu, KVM_TRACE_EXIT_SIGNAL);
1421 		}
1422 	}
1423 
1424 	if (ret == RESUME_GUEST) {
1425 		trace_kvm_reenter(vcpu);
1426 
1427 		/*
1428 		 * Make sure the read of VCPU requests in vcpu_reenter()
1429 		 * callback is not reordered ahead of the write to vcpu->mode,
1430 		 * or we could miss a TLB flush request while the requester sees
1431 		 * the VCPU as outside of guest mode and not needing an IPI.
1432 		 */
1433 		smp_store_mb(vcpu->mode, IN_GUEST_MODE);
1434 
1435 		kvm_mips_callbacks->vcpu_reenter(run, vcpu);
1436 
1437 		/*
1438 		 * If FPU / MSA are enabled (i.e. the guest's FPU / MSA context
1439 		 * is live), restore FCR31 / MSACSR.
1440 		 *
1441 		 * This should be before returning to the guest exception
1442 		 * vector, as it may well cause an [MSA] FP exception if there
1443 		 * are pending exception bits unmasked. (see
1444 		 * kvm_mips_csr_die_notifier() for how that is handled).
1445 		 */
1446 		if (kvm_mips_guest_has_fpu(&vcpu->arch) &&
1447 		    read_c0_status() & ST0_CU1)
1448 			__kvm_restore_fcsr(&vcpu->arch);
1449 
1450 		if (kvm_mips_guest_has_msa(&vcpu->arch) &&
1451 		    read_c0_config5() & MIPS_CONF5_MSAEN)
1452 			__kvm_restore_msacsr(&vcpu->arch);
1453 	}
1454 
1455 	/* Disable HTW before returning to guest or host */
1456 	if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ))
1457 		htw_stop();
1458 
1459 	return ret;
1460 }
1461 
1462 /* Enable FPU for guest and restore context */
1463 void kvm_own_fpu(struct kvm_vcpu *vcpu)
1464 {
1465 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1466 	unsigned int sr, cfg5;
1467 
1468 	preempt_disable();
1469 
1470 	sr = kvm_read_c0_guest_status(cop0);
1471 
1472 	/*
1473 	 * If MSA state is already live, it is undefined how it interacts with
1474 	 * FR=0 FPU state, and we don't want to hit reserved instruction
1475 	 * exceptions trying to save the MSA state later when CU=1 && FR=1, so
1476 	 * play it safe and save it first.
1477 	 *
1478 	 * In theory we shouldn't ever hit this case since kvm_lose_fpu() should
1479 	 * get called when guest CU1 is set, however we can't trust the guest
1480 	 * not to clobber the status register directly via the commpage.
1481 	 */
1482 	if (cpu_has_msa && sr & ST0_CU1 && !(sr & ST0_FR) &&
1483 	    vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA)
1484 		kvm_lose_fpu(vcpu);
1485 
1486 	/*
1487 	 * Enable FPU for guest
1488 	 * We set FR and FRE according to guest context
1489 	 */
1490 	change_c0_status(ST0_CU1 | ST0_FR, sr);
1491 	if (cpu_has_fre) {
1492 		cfg5 = kvm_read_c0_guest_config5(cop0);
1493 		change_c0_config5(MIPS_CONF5_FRE, cfg5);
1494 	}
1495 	enable_fpu_hazard();
1496 
1497 	/* If guest FPU state not active, restore it now */
1498 	if (!(vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU)) {
1499 		__kvm_restore_fpu(&vcpu->arch);
1500 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1501 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_FPU);
1502 	} else {
1503 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_FPU);
1504 	}
1505 
1506 	preempt_enable();
1507 }
1508 
1509 #ifdef CONFIG_CPU_HAS_MSA
1510 /* Enable MSA for guest and restore context */
1511 void kvm_own_msa(struct kvm_vcpu *vcpu)
1512 {
1513 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1514 	unsigned int sr, cfg5;
1515 
1516 	preempt_disable();
1517 
1518 	/*
1519 	 * Enable FPU if enabled in guest, since we're restoring FPU context
1520 	 * anyway. We set FR and FRE according to guest context.
1521 	 */
1522 	if (kvm_mips_guest_has_fpu(&vcpu->arch)) {
1523 		sr = kvm_read_c0_guest_status(cop0);
1524 
1525 		/*
1526 		 * If FR=0 FPU state is already live, it is undefined how it
1527 		 * interacts with MSA state, so play it safe and save it first.
1528 		 */
1529 		if (!(sr & ST0_FR) &&
1530 		    (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU |
1531 				KVM_MIPS_AUX_MSA)) == KVM_MIPS_AUX_FPU)
1532 			kvm_lose_fpu(vcpu);
1533 
1534 		change_c0_status(ST0_CU1 | ST0_FR, sr);
1535 		if (sr & ST0_CU1 && cpu_has_fre) {
1536 			cfg5 = kvm_read_c0_guest_config5(cop0);
1537 			change_c0_config5(MIPS_CONF5_FRE, cfg5);
1538 		}
1539 	}
1540 
1541 	/* Enable MSA for guest */
1542 	set_c0_config5(MIPS_CONF5_MSAEN);
1543 	enable_fpu_hazard();
1544 
1545 	switch (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA)) {
1546 	case KVM_MIPS_AUX_FPU:
1547 		/*
1548 		 * Guest FPU state already loaded, only restore upper MSA state
1549 		 */
1550 		__kvm_restore_msa_upper(&vcpu->arch);
1551 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1552 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_MSA);
1553 		break;
1554 	case 0:
1555 		/* Neither FPU or MSA already active, restore full MSA state */
1556 		__kvm_restore_msa(&vcpu->arch);
1557 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1558 		if (kvm_mips_guest_has_fpu(&vcpu->arch))
1559 			vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1560 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE,
1561 			      KVM_TRACE_AUX_FPU_MSA);
1562 		break;
1563 	default:
1564 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_MSA);
1565 		break;
1566 	}
1567 
1568 	preempt_enable();
1569 }
1570 #endif
1571 
1572 /* Drop FPU & MSA without saving it */
1573 void kvm_drop_fpu(struct kvm_vcpu *vcpu)
1574 {
1575 	preempt_disable();
1576 	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1577 		disable_msa();
1578 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_MSA);
1579 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_MSA;
1580 	}
1581 	if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1582 		clear_c0_status(ST0_CU1 | ST0_FR);
1583 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_FPU);
1584 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1585 	}
1586 	preempt_enable();
1587 }
1588 
1589 /* Save and disable FPU & MSA */
1590 void kvm_lose_fpu(struct kvm_vcpu *vcpu)
1591 {
1592 	/*
1593 	 * With T&E, FPU & MSA get disabled in root context (hardware) when it
1594 	 * is disabled in guest context (software), but the register state in
1595 	 * the hardware may still be in use.
1596 	 * This is why we explicitly re-enable the hardware before saving.
1597 	 */
1598 
1599 	preempt_disable();
1600 	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1601 		if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) {
1602 			set_c0_config5(MIPS_CONF5_MSAEN);
1603 			enable_fpu_hazard();
1604 		}
1605 
1606 		__kvm_save_msa(&vcpu->arch);
1607 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU_MSA);
1608 
1609 		/* Disable MSA & FPU */
1610 		disable_msa();
1611 		if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1612 			clear_c0_status(ST0_CU1 | ST0_FR);
1613 			disable_fpu_hazard();
1614 		}
1615 		vcpu->arch.aux_inuse &= ~(KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA);
1616 	} else if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1617 		if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) {
1618 			set_c0_status(ST0_CU1);
1619 			enable_fpu_hazard();
1620 		}
1621 
1622 		__kvm_save_fpu(&vcpu->arch);
1623 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1624 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU);
1625 
1626 		/* Disable FPU */
1627 		clear_c0_status(ST0_CU1 | ST0_FR);
1628 		disable_fpu_hazard();
1629 	}
1630 	preempt_enable();
1631 }
1632 
1633 /*
1634  * Step over a specific ctc1 to FCSR and a specific ctcmsa to MSACSR which are
1635  * used to restore guest FCSR/MSACSR state and may trigger a "harmless" FP/MSAFP
1636  * exception if cause bits are set in the value being written.
1637  */
1638 static int kvm_mips_csr_die_notify(struct notifier_block *self,
1639 				   unsigned long cmd, void *ptr)
1640 {
1641 	struct die_args *args = (struct die_args *)ptr;
1642 	struct pt_regs *regs = args->regs;
1643 	unsigned long pc;
1644 
1645 	/* Only interested in FPE and MSAFPE */
1646 	if (cmd != DIE_FP && cmd != DIE_MSAFP)
1647 		return NOTIFY_DONE;
1648 
1649 	/* Return immediately if guest context isn't active */
1650 	if (!(current->flags & PF_VCPU))
1651 		return NOTIFY_DONE;
1652 
1653 	/* Should never get here from user mode */
1654 	BUG_ON(user_mode(regs));
1655 
1656 	pc = instruction_pointer(regs);
1657 	switch (cmd) {
1658 	case DIE_FP:
1659 		/* match 2nd instruction in __kvm_restore_fcsr */
1660 		if (pc != (unsigned long)&__kvm_restore_fcsr + 4)
1661 			return NOTIFY_DONE;
1662 		break;
1663 	case DIE_MSAFP:
1664 		/* match 2nd/3rd instruction in __kvm_restore_msacsr */
1665 		if (!cpu_has_msa ||
1666 		    pc < (unsigned long)&__kvm_restore_msacsr + 4 ||
1667 		    pc > (unsigned long)&__kvm_restore_msacsr + 8)
1668 			return NOTIFY_DONE;
1669 		break;
1670 	}
1671 
1672 	/* Move PC forward a little and continue executing */
1673 	instruction_pointer(regs) += 4;
1674 
1675 	return NOTIFY_STOP;
1676 }
1677 
1678 static struct notifier_block kvm_mips_csr_die_notifier = {
1679 	.notifier_call = kvm_mips_csr_die_notify,
1680 };
1681 
1682 static int __init kvm_mips_init(void)
1683 {
1684 	int ret;
1685 
1686 	if (cpu_has_mmid) {
1687 		pr_warn("KVM does not yet support MMIDs. KVM Disabled\n");
1688 		return -EOPNOTSUPP;
1689 	}
1690 
1691 	ret = kvm_mips_entry_setup();
1692 	if (ret)
1693 		return ret;
1694 
1695 	ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
1696 
1697 	if (ret)
1698 		return ret;
1699 
1700 	register_die_notifier(&kvm_mips_csr_die_notifier);
1701 
1702 	return 0;
1703 }
1704 
1705 static void __exit kvm_mips_exit(void)
1706 {
1707 	kvm_exit();
1708 
1709 	unregister_die_notifier(&kvm_mips_csr_die_notifier);
1710 }
1711 
1712 module_init(kvm_mips_init);
1713 module_exit(kvm_mips_exit);
1714 
1715 EXPORT_TRACEPOINT_SYMBOL(kvm_exit);
1716