xref: /openbmc/linux/arch/mips/kvm/mips.c (revision 5f2fb52fac15a8a8e10ce020dd532504a8abfc4e)
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 int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
284 {
285 	return 0;
286 }
287 
288 int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
289 {
290 	int err, size;
291 	void *gebase, *p, *handler, *refill_start, *refill_end;
292 	int i;
293 
294 	kvm_debug("kvm @ %p: create cpu %d at %p\n",
295 		  vcpu->kvm, vcpu->vcpu_id, vcpu);
296 
297 	err = kvm_mips_callbacks->vcpu_init(vcpu);
298 	if (err)
299 		return err;
300 
301 	hrtimer_init(&vcpu->arch.comparecount_timer, CLOCK_MONOTONIC,
302 		     HRTIMER_MODE_REL);
303 	vcpu->arch.comparecount_timer.function = kvm_mips_comparecount_wakeup;
304 
305 	/*
306 	 * Allocate space for host mode exception handlers that handle
307 	 * guest mode exits
308 	 */
309 	if (cpu_has_veic || cpu_has_vint)
310 		size = 0x200 + VECTORSPACING * 64;
311 	else
312 		size = 0x4000;
313 
314 	gebase = kzalloc(ALIGN(size, PAGE_SIZE), GFP_KERNEL);
315 
316 	if (!gebase) {
317 		err = -ENOMEM;
318 		goto out_uninit_vcpu;
319 	}
320 	kvm_debug("Allocated %d bytes for KVM Exception Handlers @ %p\n",
321 		  ALIGN(size, PAGE_SIZE), gebase);
322 
323 	/*
324 	 * Check new ebase actually fits in CP0_EBase. The lack of a write gate
325 	 * limits us to the low 512MB of physical address space. If the memory
326 	 * we allocate is out of range, just give up now.
327 	 */
328 	if (!cpu_has_ebase_wg && virt_to_phys(gebase) >= 0x20000000) {
329 		kvm_err("CP0_EBase.WG required for guest exception base %pK\n",
330 			gebase);
331 		err = -ENOMEM;
332 		goto out_free_gebase;
333 	}
334 
335 	/* Save new ebase */
336 	vcpu->arch.guest_ebase = gebase;
337 
338 	/* Build guest exception vectors dynamically in unmapped memory */
339 	handler = gebase + 0x2000;
340 
341 	/* TLB refill (or XTLB refill on 64-bit VZ where KX=1) */
342 	refill_start = gebase;
343 	if (IS_ENABLED(CONFIG_KVM_MIPS_VZ) && IS_ENABLED(CONFIG_64BIT))
344 		refill_start += 0x080;
345 	refill_end = kvm_mips_build_tlb_refill_exception(refill_start, handler);
346 
347 	/* General Exception Entry point */
348 	kvm_mips_build_exception(gebase + 0x180, handler);
349 
350 	/* For vectored interrupts poke the exception code @ all offsets 0-7 */
351 	for (i = 0; i < 8; i++) {
352 		kvm_debug("L1 Vectored handler @ %p\n",
353 			  gebase + 0x200 + (i * VECTORSPACING));
354 		kvm_mips_build_exception(gebase + 0x200 + i * VECTORSPACING,
355 					 handler);
356 	}
357 
358 	/* General exit handler */
359 	p = handler;
360 	p = kvm_mips_build_exit(p);
361 
362 	/* Guest entry routine */
363 	vcpu->arch.vcpu_run = p;
364 	p = kvm_mips_build_vcpu_run(p);
365 
366 	/* Dump the generated code */
367 	pr_debug("#include <asm/asm.h>\n");
368 	pr_debug("#include <asm/regdef.h>\n");
369 	pr_debug("\n");
370 	dump_handler("kvm_vcpu_run", vcpu->arch.vcpu_run, p);
371 	dump_handler("kvm_tlb_refill", refill_start, refill_end);
372 	dump_handler("kvm_gen_exc", gebase + 0x180, gebase + 0x200);
373 	dump_handler("kvm_exit", gebase + 0x2000, vcpu->arch.vcpu_run);
374 
375 	/* Invalidate the icache for these ranges */
376 	flush_icache_range((unsigned long)gebase,
377 			   (unsigned long)gebase + ALIGN(size, PAGE_SIZE));
378 
379 	/*
380 	 * Allocate comm page for guest kernel, a TLB will be reserved for
381 	 * mapping GVA @ 0xFFFF8000 to this page
382 	 */
383 	vcpu->arch.kseg0_commpage = kzalloc(PAGE_SIZE << 1, GFP_KERNEL);
384 
385 	if (!vcpu->arch.kseg0_commpage) {
386 		err = -ENOMEM;
387 		goto out_free_gebase;
388 	}
389 
390 	kvm_debug("Allocated COMM page @ %p\n", vcpu->arch.kseg0_commpage);
391 	kvm_mips_commpage_init(vcpu);
392 
393 	/* Init */
394 	vcpu->arch.last_sched_cpu = -1;
395 	vcpu->arch.last_exec_cpu = -1;
396 
397 	/* Initial guest state */
398 	err = kvm_mips_callbacks->vcpu_setup(vcpu);
399 	if (err)
400 		goto out_free_commpage;
401 
402 	return 0;
403 
404 out_free_commpage:
405 	kfree(vcpu->arch.kseg0_commpage);
406 out_free_gebase:
407 	kfree(gebase);
408 out_uninit_vcpu:
409 	kvm_mips_callbacks->vcpu_uninit(vcpu);
410 	return err;
411 }
412 
413 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
414 {
415 	hrtimer_cancel(&vcpu->arch.comparecount_timer);
416 
417 	kvm_mips_dump_stats(vcpu);
418 
419 	kvm_mmu_free_memory_caches(vcpu);
420 	kfree(vcpu->arch.guest_ebase);
421 	kfree(vcpu->arch.kseg0_commpage);
422 
423 	kvm_mips_callbacks->vcpu_uninit(vcpu);
424 }
425 
426 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
427 					struct kvm_guest_debug *dbg)
428 {
429 	return -ENOIOCTLCMD;
430 }
431 
432 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
433 {
434 	int r = -EINTR;
435 
436 	vcpu_load(vcpu);
437 
438 	kvm_sigset_activate(vcpu);
439 
440 	if (vcpu->mmio_needed) {
441 		if (!vcpu->mmio_is_write)
442 			kvm_mips_complete_mmio_load(vcpu, run);
443 		vcpu->mmio_needed = 0;
444 	}
445 
446 	if (run->immediate_exit)
447 		goto out;
448 
449 	lose_fpu(1);
450 
451 	local_irq_disable();
452 	guest_enter_irqoff();
453 	trace_kvm_enter(vcpu);
454 
455 	/*
456 	 * Make sure the read of VCPU requests in vcpu_run() callback is not
457 	 * reordered ahead of the write to vcpu->mode, or we could miss a TLB
458 	 * flush request while the requester sees the VCPU as outside of guest
459 	 * mode and not needing an IPI.
460 	 */
461 	smp_store_mb(vcpu->mode, IN_GUEST_MODE);
462 
463 	r = kvm_mips_callbacks->vcpu_run(run, vcpu);
464 
465 	trace_kvm_out(vcpu);
466 	guest_exit_irqoff();
467 	local_irq_enable();
468 
469 out:
470 	kvm_sigset_deactivate(vcpu);
471 
472 	vcpu_put(vcpu);
473 	return r;
474 }
475 
476 int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
477 			     struct kvm_mips_interrupt *irq)
478 {
479 	int intr = (int)irq->irq;
480 	struct kvm_vcpu *dvcpu = NULL;
481 
482 	if (intr == 3 || intr == -3 || intr == 4 || intr == -4)
483 		kvm_debug("%s: CPU: %d, INTR: %d\n", __func__, irq->cpu,
484 			  (int)intr);
485 
486 	if (irq->cpu == -1)
487 		dvcpu = vcpu;
488 	else
489 		dvcpu = vcpu->kvm->vcpus[irq->cpu];
490 
491 	if (intr == 2 || intr == 3 || intr == 4) {
492 		kvm_mips_callbacks->queue_io_int(dvcpu, irq);
493 
494 	} else if (intr == -2 || intr == -3 || intr == -4) {
495 		kvm_mips_callbacks->dequeue_io_int(dvcpu, irq);
496 	} else {
497 		kvm_err("%s: invalid interrupt ioctl (%d:%d)\n", __func__,
498 			irq->cpu, irq->irq);
499 		return -EINVAL;
500 	}
501 
502 	dvcpu->arch.wait = 0;
503 
504 	if (swq_has_sleeper(&dvcpu->wq))
505 		swake_up_one(&dvcpu->wq);
506 
507 	return 0;
508 }
509 
510 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
511 				    struct kvm_mp_state *mp_state)
512 {
513 	return -ENOIOCTLCMD;
514 }
515 
516 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
517 				    struct kvm_mp_state *mp_state)
518 {
519 	return -ENOIOCTLCMD;
520 }
521 
522 static u64 kvm_mips_get_one_regs[] = {
523 	KVM_REG_MIPS_R0,
524 	KVM_REG_MIPS_R1,
525 	KVM_REG_MIPS_R2,
526 	KVM_REG_MIPS_R3,
527 	KVM_REG_MIPS_R4,
528 	KVM_REG_MIPS_R5,
529 	KVM_REG_MIPS_R6,
530 	KVM_REG_MIPS_R7,
531 	KVM_REG_MIPS_R8,
532 	KVM_REG_MIPS_R9,
533 	KVM_REG_MIPS_R10,
534 	KVM_REG_MIPS_R11,
535 	KVM_REG_MIPS_R12,
536 	KVM_REG_MIPS_R13,
537 	KVM_REG_MIPS_R14,
538 	KVM_REG_MIPS_R15,
539 	KVM_REG_MIPS_R16,
540 	KVM_REG_MIPS_R17,
541 	KVM_REG_MIPS_R18,
542 	KVM_REG_MIPS_R19,
543 	KVM_REG_MIPS_R20,
544 	KVM_REG_MIPS_R21,
545 	KVM_REG_MIPS_R22,
546 	KVM_REG_MIPS_R23,
547 	KVM_REG_MIPS_R24,
548 	KVM_REG_MIPS_R25,
549 	KVM_REG_MIPS_R26,
550 	KVM_REG_MIPS_R27,
551 	KVM_REG_MIPS_R28,
552 	KVM_REG_MIPS_R29,
553 	KVM_REG_MIPS_R30,
554 	KVM_REG_MIPS_R31,
555 
556 #ifndef CONFIG_CPU_MIPSR6
557 	KVM_REG_MIPS_HI,
558 	KVM_REG_MIPS_LO,
559 #endif
560 	KVM_REG_MIPS_PC,
561 };
562 
563 static u64 kvm_mips_get_one_regs_fpu[] = {
564 	KVM_REG_MIPS_FCR_IR,
565 	KVM_REG_MIPS_FCR_CSR,
566 };
567 
568 static u64 kvm_mips_get_one_regs_msa[] = {
569 	KVM_REG_MIPS_MSA_IR,
570 	KVM_REG_MIPS_MSA_CSR,
571 };
572 
573 static unsigned long kvm_mips_num_regs(struct kvm_vcpu *vcpu)
574 {
575 	unsigned long ret;
576 
577 	ret = ARRAY_SIZE(kvm_mips_get_one_regs);
578 	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
579 		ret += ARRAY_SIZE(kvm_mips_get_one_regs_fpu) + 48;
580 		/* odd doubles */
581 		if (boot_cpu_data.fpu_id & MIPS_FPIR_F64)
582 			ret += 16;
583 	}
584 	if (kvm_mips_guest_can_have_msa(&vcpu->arch))
585 		ret += ARRAY_SIZE(kvm_mips_get_one_regs_msa) + 32;
586 	ret += kvm_mips_callbacks->num_regs(vcpu);
587 
588 	return ret;
589 }
590 
591 static int kvm_mips_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices)
592 {
593 	u64 index;
594 	unsigned int i;
595 
596 	if (copy_to_user(indices, kvm_mips_get_one_regs,
597 			 sizeof(kvm_mips_get_one_regs)))
598 		return -EFAULT;
599 	indices += ARRAY_SIZE(kvm_mips_get_one_regs);
600 
601 	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
602 		if (copy_to_user(indices, kvm_mips_get_one_regs_fpu,
603 				 sizeof(kvm_mips_get_one_regs_fpu)))
604 			return -EFAULT;
605 		indices += ARRAY_SIZE(kvm_mips_get_one_regs_fpu);
606 
607 		for (i = 0; i < 32; ++i) {
608 			index = KVM_REG_MIPS_FPR_32(i);
609 			if (copy_to_user(indices, &index, sizeof(index)))
610 				return -EFAULT;
611 			++indices;
612 
613 			/* skip odd doubles if no F64 */
614 			if (i & 1 && !(boot_cpu_data.fpu_id & MIPS_FPIR_F64))
615 				continue;
616 
617 			index = KVM_REG_MIPS_FPR_64(i);
618 			if (copy_to_user(indices, &index, sizeof(index)))
619 				return -EFAULT;
620 			++indices;
621 		}
622 	}
623 
624 	if (kvm_mips_guest_can_have_msa(&vcpu->arch)) {
625 		if (copy_to_user(indices, kvm_mips_get_one_regs_msa,
626 				 sizeof(kvm_mips_get_one_regs_msa)))
627 			return -EFAULT;
628 		indices += ARRAY_SIZE(kvm_mips_get_one_regs_msa);
629 
630 		for (i = 0; i < 32; ++i) {
631 			index = KVM_REG_MIPS_VEC_128(i);
632 			if (copy_to_user(indices, &index, sizeof(index)))
633 				return -EFAULT;
634 			++indices;
635 		}
636 	}
637 
638 	return kvm_mips_callbacks->copy_reg_indices(vcpu, indices);
639 }
640 
641 static int kvm_mips_get_reg(struct kvm_vcpu *vcpu,
642 			    const struct kvm_one_reg *reg)
643 {
644 	struct mips_coproc *cop0 = vcpu->arch.cop0;
645 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
646 	int ret;
647 	s64 v;
648 	s64 vs[2];
649 	unsigned int idx;
650 
651 	switch (reg->id) {
652 	/* General purpose registers */
653 	case KVM_REG_MIPS_R0 ... KVM_REG_MIPS_R31:
654 		v = (long)vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0];
655 		break;
656 #ifndef CONFIG_CPU_MIPSR6
657 	case KVM_REG_MIPS_HI:
658 		v = (long)vcpu->arch.hi;
659 		break;
660 	case KVM_REG_MIPS_LO:
661 		v = (long)vcpu->arch.lo;
662 		break;
663 #endif
664 	case KVM_REG_MIPS_PC:
665 		v = (long)vcpu->arch.pc;
666 		break;
667 
668 	/* Floating point registers */
669 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
670 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
671 			return -EINVAL;
672 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
673 		/* Odd singles in top of even double when FR=0 */
674 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
675 			v = get_fpr32(&fpu->fpr[idx], 0);
676 		else
677 			v = get_fpr32(&fpu->fpr[idx & ~1], idx & 1);
678 		break;
679 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
680 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
681 			return -EINVAL;
682 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
683 		/* Can't access odd doubles in FR=0 mode */
684 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
685 			return -EINVAL;
686 		v = get_fpr64(&fpu->fpr[idx], 0);
687 		break;
688 	case KVM_REG_MIPS_FCR_IR:
689 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
690 			return -EINVAL;
691 		v = boot_cpu_data.fpu_id;
692 		break;
693 	case KVM_REG_MIPS_FCR_CSR:
694 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
695 			return -EINVAL;
696 		v = fpu->fcr31;
697 		break;
698 
699 	/* MIPS SIMD Architecture (MSA) registers */
700 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
701 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
702 			return -EINVAL;
703 		/* Can't access MSA registers in FR=0 mode */
704 		if (!(kvm_read_c0_guest_status(cop0) & ST0_FR))
705 			return -EINVAL;
706 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
707 #ifdef CONFIG_CPU_LITTLE_ENDIAN
708 		/* least significant byte first */
709 		vs[0] = get_fpr64(&fpu->fpr[idx], 0);
710 		vs[1] = get_fpr64(&fpu->fpr[idx], 1);
711 #else
712 		/* most significant byte first */
713 		vs[0] = get_fpr64(&fpu->fpr[idx], 1);
714 		vs[1] = get_fpr64(&fpu->fpr[idx], 0);
715 #endif
716 		break;
717 	case KVM_REG_MIPS_MSA_IR:
718 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
719 			return -EINVAL;
720 		v = boot_cpu_data.msa_id;
721 		break;
722 	case KVM_REG_MIPS_MSA_CSR:
723 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
724 			return -EINVAL;
725 		v = fpu->msacsr;
726 		break;
727 
728 	/* registers to be handled specially */
729 	default:
730 		ret = kvm_mips_callbacks->get_one_reg(vcpu, reg, &v);
731 		if (ret)
732 			return ret;
733 		break;
734 	}
735 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
736 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
737 
738 		return put_user(v, uaddr64);
739 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
740 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
741 		u32 v32 = (u32)v;
742 
743 		return put_user(v32, uaddr32);
744 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
745 		void __user *uaddr = (void __user *)(long)reg->addr;
746 
747 		return copy_to_user(uaddr, vs, 16) ? -EFAULT : 0;
748 	} else {
749 		return -EINVAL;
750 	}
751 }
752 
753 static int kvm_mips_set_reg(struct kvm_vcpu *vcpu,
754 			    const struct kvm_one_reg *reg)
755 {
756 	struct mips_coproc *cop0 = vcpu->arch.cop0;
757 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
758 	s64 v;
759 	s64 vs[2];
760 	unsigned int idx;
761 
762 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
763 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
764 
765 		if (get_user(v, uaddr64) != 0)
766 			return -EFAULT;
767 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
768 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
769 		s32 v32;
770 
771 		if (get_user(v32, uaddr32) != 0)
772 			return -EFAULT;
773 		v = (s64)v32;
774 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
775 		void __user *uaddr = (void __user *)(long)reg->addr;
776 
777 		return copy_from_user(vs, uaddr, 16) ? -EFAULT : 0;
778 	} else {
779 		return -EINVAL;
780 	}
781 
782 	switch (reg->id) {
783 	/* General purpose registers */
784 	case KVM_REG_MIPS_R0:
785 		/* Silently ignore requests to set $0 */
786 		break;
787 	case KVM_REG_MIPS_R1 ... KVM_REG_MIPS_R31:
788 		vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0] = v;
789 		break;
790 #ifndef CONFIG_CPU_MIPSR6
791 	case KVM_REG_MIPS_HI:
792 		vcpu->arch.hi = v;
793 		break;
794 	case KVM_REG_MIPS_LO:
795 		vcpu->arch.lo = v;
796 		break;
797 #endif
798 	case KVM_REG_MIPS_PC:
799 		vcpu->arch.pc = v;
800 		break;
801 
802 	/* Floating point registers */
803 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
804 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
805 			return -EINVAL;
806 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
807 		/* Odd singles in top of even double when FR=0 */
808 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
809 			set_fpr32(&fpu->fpr[idx], 0, v);
810 		else
811 			set_fpr32(&fpu->fpr[idx & ~1], idx & 1, v);
812 		break;
813 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
814 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
815 			return -EINVAL;
816 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
817 		/* Can't access odd doubles in FR=0 mode */
818 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
819 			return -EINVAL;
820 		set_fpr64(&fpu->fpr[idx], 0, v);
821 		break;
822 	case KVM_REG_MIPS_FCR_IR:
823 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
824 			return -EINVAL;
825 		/* Read-only */
826 		break;
827 	case KVM_REG_MIPS_FCR_CSR:
828 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
829 			return -EINVAL;
830 		fpu->fcr31 = v;
831 		break;
832 
833 	/* MIPS SIMD Architecture (MSA) registers */
834 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
835 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
836 			return -EINVAL;
837 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
838 #ifdef CONFIG_CPU_LITTLE_ENDIAN
839 		/* least significant byte first */
840 		set_fpr64(&fpu->fpr[idx], 0, vs[0]);
841 		set_fpr64(&fpu->fpr[idx], 1, vs[1]);
842 #else
843 		/* most significant byte first */
844 		set_fpr64(&fpu->fpr[idx], 1, vs[0]);
845 		set_fpr64(&fpu->fpr[idx], 0, vs[1]);
846 #endif
847 		break;
848 	case KVM_REG_MIPS_MSA_IR:
849 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
850 			return -EINVAL;
851 		/* Read-only */
852 		break;
853 	case KVM_REG_MIPS_MSA_CSR:
854 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
855 			return -EINVAL;
856 		fpu->msacsr = v;
857 		break;
858 
859 	/* registers to be handled specially */
860 	default:
861 		return kvm_mips_callbacks->set_one_reg(vcpu, reg, v);
862 	}
863 	return 0;
864 }
865 
866 static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
867 				     struct kvm_enable_cap *cap)
868 {
869 	int r = 0;
870 
871 	if (!kvm_vm_ioctl_check_extension(vcpu->kvm, cap->cap))
872 		return -EINVAL;
873 	if (cap->flags)
874 		return -EINVAL;
875 	if (cap->args[0])
876 		return -EINVAL;
877 
878 	switch (cap->cap) {
879 	case KVM_CAP_MIPS_FPU:
880 		vcpu->arch.fpu_enabled = true;
881 		break;
882 	case KVM_CAP_MIPS_MSA:
883 		vcpu->arch.msa_enabled = true;
884 		break;
885 	default:
886 		r = -EINVAL;
887 		break;
888 	}
889 
890 	return r;
891 }
892 
893 long kvm_arch_vcpu_async_ioctl(struct file *filp, unsigned int ioctl,
894 			       unsigned long arg)
895 {
896 	struct kvm_vcpu *vcpu = filp->private_data;
897 	void __user *argp = (void __user *)arg;
898 
899 	if (ioctl == KVM_INTERRUPT) {
900 		struct kvm_mips_interrupt irq;
901 
902 		if (copy_from_user(&irq, argp, sizeof(irq)))
903 			return -EFAULT;
904 		kvm_debug("[%d] %s: irq: %d\n", vcpu->vcpu_id, __func__,
905 			  irq.irq);
906 
907 		return kvm_vcpu_ioctl_interrupt(vcpu, &irq);
908 	}
909 
910 	return -ENOIOCTLCMD;
911 }
912 
913 long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl,
914 			 unsigned long arg)
915 {
916 	struct kvm_vcpu *vcpu = filp->private_data;
917 	void __user *argp = (void __user *)arg;
918 	long r;
919 
920 	vcpu_load(vcpu);
921 
922 	switch (ioctl) {
923 	case KVM_SET_ONE_REG:
924 	case KVM_GET_ONE_REG: {
925 		struct kvm_one_reg reg;
926 
927 		r = -EFAULT;
928 		if (copy_from_user(&reg, argp, sizeof(reg)))
929 			break;
930 		if (ioctl == KVM_SET_ONE_REG)
931 			r = kvm_mips_set_reg(vcpu, &reg);
932 		else
933 			r = kvm_mips_get_reg(vcpu, &reg);
934 		break;
935 	}
936 	case KVM_GET_REG_LIST: {
937 		struct kvm_reg_list __user *user_list = argp;
938 		struct kvm_reg_list reg_list;
939 		unsigned n;
940 
941 		r = -EFAULT;
942 		if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
943 			break;
944 		n = reg_list.n;
945 		reg_list.n = kvm_mips_num_regs(vcpu);
946 		if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
947 			break;
948 		r = -E2BIG;
949 		if (n < reg_list.n)
950 			break;
951 		r = kvm_mips_copy_reg_indices(vcpu, user_list->reg);
952 		break;
953 	}
954 	case KVM_ENABLE_CAP: {
955 		struct kvm_enable_cap cap;
956 
957 		r = -EFAULT;
958 		if (copy_from_user(&cap, argp, sizeof(cap)))
959 			break;
960 		r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
961 		break;
962 	}
963 	default:
964 		r = -ENOIOCTLCMD;
965 	}
966 
967 	vcpu_put(vcpu);
968 	return r;
969 }
970 
971 /**
972  * kvm_vm_ioctl_get_dirty_log - get and clear the log of dirty pages in a slot
973  * @kvm: kvm instance
974  * @log: slot id and address to which we copy the log
975  *
976  * Steps 1-4 below provide general overview of dirty page logging. See
977  * kvm_get_dirty_log_protect() function description for additional details.
978  *
979  * We call kvm_get_dirty_log_protect() to handle steps 1-3, upon return we
980  * always flush the TLB (step 4) even if previous step failed  and the dirty
981  * bitmap may be corrupt. Regardless of previous outcome the KVM logging API
982  * does not preclude user space subsequent dirty log read. Flushing TLB ensures
983  * writes will be marked dirty for next log read.
984  *
985  *   1. Take a snapshot of the bit and clear it if needed.
986  *   2. Write protect the corresponding page.
987  *   3. Copy the snapshot to the userspace.
988  *   4. Flush TLB's if needed.
989  */
990 int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log)
991 {
992 	struct kvm_memslots *slots;
993 	struct kvm_memory_slot *memslot;
994 	bool flush = false;
995 	int r;
996 
997 	mutex_lock(&kvm->slots_lock);
998 
999 	r = kvm_get_dirty_log_protect(kvm, log, &flush);
1000 
1001 	if (flush) {
1002 		slots = kvm_memslots(kvm);
1003 		memslot = id_to_memslot(slots, log->slot);
1004 
1005 		/* Let implementation handle TLB/GVA invalidation */
1006 		kvm_mips_callbacks->flush_shadow_memslot(kvm, memslot);
1007 	}
1008 
1009 	mutex_unlock(&kvm->slots_lock);
1010 	return r;
1011 }
1012 
1013 int kvm_vm_ioctl_clear_dirty_log(struct kvm *kvm, struct kvm_clear_dirty_log *log)
1014 {
1015 	struct kvm_memslots *slots;
1016 	struct kvm_memory_slot *memslot;
1017 	bool flush = false;
1018 	int r;
1019 
1020 	mutex_lock(&kvm->slots_lock);
1021 
1022 	r = kvm_clear_dirty_log_protect(kvm, log, &flush);
1023 
1024 	if (flush) {
1025 		slots = kvm_memslots(kvm);
1026 		memslot = id_to_memslot(slots, log->slot);
1027 
1028 		/* Let implementation handle TLB/GVA invalidation */
1029 		kvm_mips_callbacks->flush_shadow_memslot(kvm, memslot);
1030 	}
1031 
1032 	mutex_unlock(&kvm->slots_lock);
1033 	return r;
1034 }
1035 
1036 long kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
1037 {
1038 	long r;
1039 
1040 	switch (ioctl) {
1041 	default:
1042 		r = -ENOIOCTLCMD;
1043 	}
1044 
1045 	return r;
1046 }
1047 
1048 int kvm_arch_init(void *opaque)
1049 {
1050 	if (kvm_mips_callbacks) {
1051 		kvm_err("kvm: module already exists\n");
1052 		return -EEXIST;
1053 	}
1054 
1055 	return kvm_mips_emulation_init(&kvm_mips_callbacks);
1056 }
1057 
1058 void kvm_arch_exit(void)
1059 {
1060 	kvm_mips_callbacks = NULL;
1061 }
1062 
1063 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
1064 				  struct kvm_sregs *sregs)
1065 {
1066 	return -ENOIOCTLCMD;
1067 }
1068 
1069 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
1070 				  struct kvm_sregs *sregs)
1071 {
1072 	return -ENOIOCTLCMD;
1073 }
1074 
1075 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
1076 {
1077 }
1078 
1079 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1080 {
1081 	return -ENOIOCTLCMD;
1082 }
1083 
1084 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1085 {
1086 	return -ENOIOCTLCMD;
1087 }
1088 
1089 vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
1090 {
1091 	return VM_FAULT_SIGBUS;
1092 }
1093 
1094 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
1095 {
1096 	int r;
1097 
1098 	switch (ext) {
1099 	case KVM_CAP_ONE_REG:
1100 	case KVM_CAP_ENABLE_CAP:
1101 	case KVM_CAP_READONLY_MEM:
1102 	case KVM_CAP_SYNC_MMU:
1103 	case KVM_CAP_IMMEDIATE_EXIT:
1104 		r = 1;
1105 		break;
1106 	case KVM_CAP_NR_VCPUS:
1107 		r = num_online_cpus();
1108 		break;
1109 	case KVM_CAP_MAX_VCPUS:
1110 		r = KVM_MAX_VCPUS;
1111 		break;
1112 	case KVM_CAP_MAX_VCPU_ID:
1113 		r = KVM_MAX_VCPU_ID;
1114 		break;
1115 	case KVM_CAP_MIPS_FPU:
1116 		/* We don't handle systems with inconsistent cpu_has_fpu */
1117 		r = !!raw_cpu_has_fpu;
1118 		break;
1119 	case KVM_CAP_MIPS_MSA:
1120 		/*
1121 		 * We don't support MSA vector partitioning yet:
1122 		 * 1) It would require explicit support which can't be tested
1123 		 *    yet due to lack of support in current hardware.
1124 		 * 2) It extends the state that would need to be saved/restored
1125 		 *    by e.g. QEMU for migration.
1126 		 *
1127 		 * When vector partitioning hardware becomes available, support
1128 		 * could be added by requiring a flag when enabling
1129 		 * KVM_CAP_MIPS_MSA capability to indicate that userland knows
1130 		 * to save/restore the appropriate extra state.
1131 		 */
1132 		r = cpu_has_msa && !(boot_cpu_data.msa_id & MSA_IR_WRPF);
1133 		break;
1134 	default:
1135 		r = kvm_mips_callbacks->check_extension(kvm, ext);
1136 		break;
1137 	}
1138 	return r;
1139 }
1140 
1141 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
1142 {
1143 	return kvm_mips_pending_timer(vcpu) ||
1144 		kvm_read_c0_guest_cause(vcpu->arch.cop0) & C_TI;
1145 }
1146 
1147 int kvm_arch_vcpu_dump_regs(struct kvm_vcpu *vcpu)
1148 {
1149 	int i;
1150 	struct mips_coproc *cop0;
1151 
1152 	if (!vcpu)
1153 		return -1;
1154 
1155 	kvm_debug("VCPU Register Dump:\n");
1156 	kvm_debug("\tpc = 0x%08lx\n", vcpu->arch.pc);
1157 	kvm_debug("\texceptions: %08lx\n", vcpu->arch.pending_exceptions);
1158 
1159 	for (i = 0; i < 32; i += 4) {
1160 		kvm_debug("\tgpr%02d: %08lx %08lx %08lx %08lx\n", i,
1161 		       vcpu->arch.gprs[i],
1162 		       vcpu->arch.gprs[i + 1],
1163 		       vcpu->arch.gprs[i + 2], vcpu->arch.gprs[i + 3]);
1164 	}
1165 	kvm_debug("\thi: 0x%08lx\n", vcpu->arch.hi);
1166 	kvm_debug("\tlo: 0x%08lx\n", vcpu->arch.lo);
1167 
1168 	cop0 = vcpu->arch.cop0;
1169 	kvm_debug("\tStatus: 0x%08x, Cause: 0x%08x\n",
1170 		  kvm_read_c0_guest_status(cop0),
1171 		  kvm_read_c0_guest_cause(cop0));
1172 
1173 	kvm_debug("\tEPC: 0x%08lx\n", kvm_read_c0_guest_epc(cop0));
1174 
1175 	return 0;
1176 }
1177 
1178 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1179 {
1180 	int i;
1181 
1182 	vcpu_load(vcpu);
1183 
1184 	for (i = 1; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1185 		vcpu->arch.gprs[i] = regs->gpr[i];
1186 	vcpu->arch.gprs[0] = 0; /* zero is special, and cannot be set. */
1187 	vcpu->arch.hi = regs->hi;
1188 	vcpu->arch.lo = regs->lo;
1189 	vcpu->arch.pc = regs->pc;
1190 
1191 	vcpu_put(vcpu);
1192 	return 0;
1193 }
1194 
1195 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1196 {
1197 	int i;
1198 
1199 	vcpu_load(vcpu);
1200 
1201 	for (i = 0; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1202 		regs->gpr[i] = vcpu->arch.gprs[i];
1203 
1204 	regs->hi = vcpu->arch.hi;
1205 	regs->lo = vcpu->arch.lo;
1206 	regs->pc = vcpu->arch.pc;
1207 
1208 	vcpu_put(vcpu);
1209 	return 0;
1210 }
1211 
1212 static void kvm_mips_comparecount_func(unsigned long data)
1213 {
1214 	struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data;
1215 
1216 	kvm_mips_callbacks->queue_timer_int(vcpu);
1217 
1218 	vcpu->arch.wait = 0;
1219 	if (swq_has_sleeper(&vcpu->wq))
1220 		swake_up_one(&vcpu->wq);
1221 }
1222 
1223 /* low level hrtimer wake routine */
1224 static enum hrtimer_restart kvm_mips_comparecount_wakeup(struct hrtimer *timer)
1225 {
1226 	struct kvm_vcpu *vcpu;
1227 
1228 	vcpu = container_of(timer, struct kvm_vcpu, arch.comparecount_timer);
1229 	kvm_mips_comparecount_func((unsigned long) vcpu);
1230 	return kvm_mips_count_timeout(vcpu);
1231 }
1232 
1233 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
1234 				  struct kvm_translation *tr)
1235 {
1236 	return 0;
1237 }
1238 
1239 static void kvm_mips_set_c0_status(void)
1240 {
1241 	u32 status = read_c0_status();
1242 
1243 	if (cpu_has_dsp)
1244 		status |= (ST0_MX);
1245 
1246 	write_c0_status(status);
1247 	ehb();
1248 }
1249 
1250 /*
1251  * Return value is in the form (errcode<<2 | RESUME_FLAG_HOST | RESUME_FLAG_NV)
1252  */
1253 int kvm_mips_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu)
1254 {
1255 	u32 cause = vcpu->arch.host_cp0_cause;
1256 	u32 exccode = (cause >> CAUSEB_EXCCODE) & 0x1f;
1257 	u32 __user *opc = (u32 __user *) vcpu->arch.pc;
1258 	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
1259 	enum emulation_result er = EMULATE_DONE;
1260 	u32 inst;
1261 	int ret = RESUME_GUEST;
1262 
1263 	vcpu->mode = OUTSIDE_GUEST_MODE;
1264 
1265 	/* re-enable HTW before enabling interrupts */
1266 	if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ))
1267 		htw_start();
1268 
1269 	/* Set a default exit reason */
1270 	run->exit_reason = KVM_EXIT_UNKNOWN;
1271 	run->ready_for_interrupt_injection = 1;
1272 
1273 	/*
1274 	 * Set the appropriate status bits based on host CPU features,
1275 	 * before we hit the scheduler
1276 	 */
1277 	kvm_mips_set_c0_status();
1278 
1279 	local_irq_enable();
1280 
1281 	kvm_debug("kvm_mips_handle_exit: cause: %#x, PC: %p, kvm_run: %p, kvm_vcpu: %p\n",
1282 			cause, opc, run, vcpu);
1283 	trace_kvm_exit(vcpu, exccode);
1284 
1285 	if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) {
1286 		/*
1287 		 * Do a privilege check, if in UM most of these exit conditions
1288 		 * end up causing an exception to be delivered to the Guest
1289 		 * Kernel
1290 		 */
1291 		er = kvm_mips_check_privilege(cause, opc, run, vcpu);
1292 		if (er == EMULATE_PRIV_FAIL) {
1293 			goto skip_emul;
1294 		} else if (er == EMULATE_FAIL) {
1295 			run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1296 			ret = RESUME_HOST;
1297 			goto skip_emul;
1298 		}
1299 	}
1300 
1301 	switch (exccode) {
1302 	case EXCCODE_INT:
1303 		kvm_debug("[%d]EXCCODE_INT @ %p\n", vcpu->vcpu_id, opc);
1304 
1305 		++vcpu->stat.int_exits;
1306 
1307 		if (need_resched())
1308 			cond_resched();
1309 
1310 		ret = RESUME_GUEST;
1311 		break;
1312 
1313 	case EXCCODE_CPU:
1314 		kvm_debug("EXCCODE_CPU: @ PC: %p\n", opc);
1315 
1316 		++vcpu->stat.cop_unusable_exits;
1317 		ret = kvm_mips_callbacks->handle_cop_unusable(vcpu);
1318 		/* XXXKYMA: Might need to return to user space */
1319 		if (run->exit_reason == KVM_EXIT_IRQ_WINDOW_OPEN)
1320 			ret = RESUME_HOST;
1321 		break;
1322 
1323 	case EXCCODE_MOD:
1324 		++vcpu->stat.tlbmod_exits;
1325 		ret = kvm_mips_callbacks->handle_tlb_mod(vcpu);
1326 		break;
1327 
1328 	case EXCCODE_TLBS:
1329 		kvm_debug("TLB ST fault:  cause %#x, status %#x, PC: %p, BadVaddr: %#lx\n",
1330 			  cause, kvm_read_c0_guest_status(vcpu->arch.cop0), opc,
1331 			  badvaddr);
1332 
1333 		++vcpu->stat.tlbmiss_st_exits;
1334 		ret = kvm_mips_callbacks->handle_tlb_st_miss(vcpu);
1335 		break;
1336 
1337 	case EXCCODE_TLBL:
1338 		kvm_debug("TLB LD fault: cause %#x, PC: %p, BadVaddr: %#lx\n",
1339 			  cause, opc, badvaddr);
1340 
1341 		++vcpu->stat.tlbmiss_ld_exits;
1342 		ret = kvm_mips_callbacks->handle_tlb_ld_miss(vcpu);
1343 		break;
1344 
1345 	case EXCCODE_ADES:
1346 		++vcpu->stat.addrerr_st_exits;
1347 		ret = kvm_mips_callbacks->handle_addr_err_st(vcpu);
1348 		break;
1349 
1350 	case EXCCODE_ADEL:
1351 		++vcpu->stat.addrerr_ld_exits;
1352 		ret = kvm_mips_callbacks->handle_addr_err_ld(vcpu);
1353 		break;
1354 
1355 	case EXCCODE_SYS:
1356 		++vcpu->stat.syscall_exits;
1357 		ret = kvm_mips_callbacks->handle_syscall(vcpu);
1358 		break;
1359 
1360 	case EXCCODE_RI:
1361 		++vcpu->stat.resvd_inst_exits;
1362 		ret = kvm_mips_callbacks->handle_res_inst(vcpu);
1363 		break;
1364 
1365 	case EXCCODE_BP:
1366 		++vcpu->stat.break_inst_exits;
1367 		ret = kvm_mips_callbacks->handle_break(vcpu);
1368 		break;
1369 
1370 	case EXCCODE_TR:
1371 		++vcpu->stat.trap_inst_exits;
1372 		ret = kvm_mips_callbacks->handle_trap(vcpu);
1373 		break;
1374 
1375 	case EXCCODE_MSAFPE:
1376 		++vcpu->stat.msa_fpe_exits;
1377 		ret = kvm_mips_callbacks->handle_msa_fpe(vcpu);
1378 		break;
1379 
1380 	case EXCCODE_FPE:
1381 		++vcpu->stat.fpe_exits;
1382 		ret = kvm_mips_callbacks->handle_fpe(vcpu);
1383 		break;
1384 
1385 	case EXCCODE_MSADIS:
1386 		++vcpu->stat.msa_disabled_exits;
1387 		ret = kvm_mips_callbacks->handle_msa_disabled(vcpu);
1388 		break;
1389 
1390 	case EXCCODE_GE:
1391 		/* defer exit accounting to handler */
1392 		ret = kvm_mips_callbacks->handle_guest_exit(vcpu);
1393 		break;
1394 
1395 	default:
1396 		if (cause & CAUSEF_BD)
1397 			opc += 1;
1398 		inst = 0;
1399 		kvm_get_badinstr(opc, vcpu, &inst);
1400 		kvm_err("Exception Code: %d, not yet handled, @ PC: %p, inst: 0x%08x  BadVaddr: %#lx Status: %#x\n",
1401 			exccode, opc, inst, badvaddr,
1402 			kvm_read_c0_guest_status(vcpu->arch.cop0));
1403 		kvm_arch_vcpu_dump_regs(vcpu);
1404 		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1405 		ret = RESUME_HOST;
1406 		break;
1407 
1408 	}
1409 
1410 skip_emul:
1411 	local_irq_disable();
1412 
1413 	if (ret == RESUME_GUEST)
1414 		kvm_vz_acquire_htimer(vcpu);
1415 
1416 	if (er == EMULATE_DONE && !(ret & RESUME_HOST))
1417 		kvm_mips_deliver_interrupts(vcpu, cause);
1418 
1419 	if (!(ret & RESUME_HOST)) {
1420 		/* Only check for signals if not already exiting to userspace */
1421 		if (signal_pending(current)) {
1422 			run->exit_reason = KVM_EXIT_INTR;
1423 			ret = (-EINTR << 2) | RESUME_HOST;
1424 			++vcpu->stat.signal_exits;
1425 			trace_kvm_exit(vcpu, KVM_TRACE_EXIT_SIGNAL);
1426 		}
1427 	}
1428 
1429 	if (ret == RESUME_GUEST) {
1430 		trace_kvm_reenter(vcpu);
1431 
1432 		/*
1433 		 * Make sure the read of VCPU requests in vcpu_reenter()
1434 		 * callback is not reordered ahead of the write to vcpu->mode,
1435 		 * or we could miss a TLB flush request while the requester sees
1436 		 * the VCPU as outside of guest mode and not needing an IPI.
1437 		 */
1438 		smp_store_mb(vcpu->mode, IN_GUEST_MODE);
1439 
1440 		kvm_mips_callbacks->vcpu_reenter(run, vcpu);
1441 
1442 		/*
1443 		 * If FPU / MSA are enabled (i.e. the guest's FPU / MSA context
1444 		 * is live), restore FCR31 / MSACSR.
1445 		 *
1446 		 * This should be before returning to the guest exception
1447 		 * vector, as it may well cause an [MSA] FP exception if there
1448 		 * are pending exception bits unmasked. (see
1449 		 * kvm_mips_csr_die_notifier() for how that is handled).
1450 		 */
1451 		if (kvm_mips_guest_has_fpu(&vcpu->arch) &&
1452 		    read_c0_status() & ST0_CU1)
1453 			__kvm_restore_fcsr(&vcpu->arch);
1454 
1455 		if (kvm_mips_guest_has_msa(&vcpu->arch) &&
1456 		    read_c0_config5() & MIPS_CONF5_MSAEN)
1457 			__kvm_restore_msacsr(&vcpu->arch);
1458 	}
1459 
1460 	/* Disable HTW before returning to guest or host */
1461 	if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ))
1462 		htw_stop();
1463 
1464 	return ret;
1465 }
1466 
1467 /* Enable FPU for guest and restore context */
1468 void kvm_own_fpu(struct kvm_vcpu *vcpu)
1469 {
1470 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1471 	unsigned int sr, cfg5;
1472 
1473 	preempt_disable();
1474 
1475 	sr = kvm_read_c0_guest_status(cop0);
1476 
1477 	/*
1478 	 * If MSA state is already live, it is undefined how it interacts with
1479 	 * FR=0 FPU state, and we don't want to hit reserved instruction
1480 	 * exceptions trying to save the MSA state later when CU=1 && FR=1, so
1481 	 * play it safe and save it first.
1482 	 *
1483 	 * In theory we shouldn't ever hit this case since kvm_lose_fpu() should
1484 	 * get called when guest CU1 is set, however we can't trust the guest
1485 	 * not to clobber the status register directly via the commpage.
1486 	 */
1487 	if (cpu_has_msa && sr & ST0_CU1 && !(sr & ST0_FR) &&
1488 	    vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA)
1489 		kvm_lose_fpu(vcpu);
1490 
1491 	/*
1492 	 * Enable FPU for guest
1493 	 * We set FR and FRE according to guest context
1494 	 */
1495 	change_c0_status(ST0_CU1 | ST0_FR, sr);
1496 	if (cpu_has_fre) {
1497 		cfg5 = kvm_read_c0_guest_config5(cop0);
1498 		change_c0_config5(MIPS_CONF5_FRE, cfg5);
1499 	}
1500 	enable_fpu_hazard();
1501 
1502 	/* If guest FPU state not active, restore it now */
1503 	if (!(vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU)) {
1504 		__kvm_restore_fpu(&vcpu->arch);
1505 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1506 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_FPU);
1507 	} else {
1508 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_FPU);
1509 	}
1510 
1511 	preempt_enable();
1512 }
1513 
1514 #ifdef CONFIG_CPU_HAS_MSA
1515 /* Enable MSA for guest and restore context */
1516 void kvm_own_msa(struct kvm_vcpu *vcpu)
1517 {
1518 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1519 	unsigned int sr, cfg5;
1520 
1521 	preempt_disable();
1522 
1523 	/*
1524 	 * Enable FPU if enabled in guest, since we're restoring FPU context
1525 	 * anyway. We set FR and FRE according to guest context.
1526 	 */
1527 	if (kvm_mips_guest_has_fpu(&vcpu->arch)) {
1528 		sr = kvm_read_c0_guest_status(cop0);
1529 
1530 		/*
1531 		 * If FR=0 FPU state is already live, it is undefined how it
1532 		 * interacts with MSA state, so play it safe and save it first.
1533 		 */
1534 		if (!(sr & ST0_FR) &&
1535 		    (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU |
1536 				KVM_MIPS_AUX_MSA)) == KVM_MIPS_AUX_FPU)
1537 			kvm_lose_fpu(vcpu);
1538 
1539 		change_c0_status(ST0_CU1 | ST0_FR, sr);
1540 		if (sr & ST0_CU1 && cpu_has_fre) {
1541 			cfg5 = kvm_read_c0_guest_config5(cop0);
1542 			change_c0_config5(MIPS_CONF5_FRE, cfg5);
1543 		}
1544 	}
1545 
1546 	/* Enable MSA for guest */
1547 	set_c0_config5(MIPS_CONF5_MSAEN);
1548 	enable_fpu_hazard();
1549 
1550 	switch (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA)) {
1551 	case KVM_MIPS_AUX_FPU:
1552 		/*
1553 		 * Guest FPU state already loaded, only restore upper MSA state
1554 		 */
1555 		__kvm_restore_msa_upper(&vcpu->arch);
1556 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1557 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_MSA);
1558 		break;
1559 	case 0:
1560 		/* Neither FPU or MSA already active, restore full MSA state */
1561 		__kvm_restore_msa(&vcpu->arch);
1562 		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
1563 		if (kvm_mips_guest_has_fpu(&vcpu->arch))
1564 			vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
1565 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE,
1566 			      KVM_TRACE_AUX_FPU_MSA);
1567 		break;
1568 	default:
1569 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_MSA);
1570 		break;
1571 	}
1572 
1573 	preempt_enable();
1574 }
1575 #endif
1576 
1577 /* Drop FPU & MSA without saving it */
1578 void kvm_drop_fpu(struct kvm_vcpu *vcpu)
1579 {
1580 	preempt_disable();
1581 	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1582 		disable_msa();
1583 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_MSA);
1584 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_MSA;
1585 	}
1586 	if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1587 		clear_c0_status(ST0_CU1 | ST0_FR);
1588 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_FPU);
1589 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1590 	}
1591 	preempt_enable();
1592 }
1593 
1594 /* Save and disable FPU & MSA */
1595 void kvm_lose_fpu(struct kvm_vcpu *vcpu)
1596 {
1597 	/*
1598 	 * With T&E, FPU & MSA get disabled in root context (hardware) when it
1599 	 * is disabled in guest context (software), but the register state in
1600 	 * the hardware may still be in use.
1601 	 * This is why we explicitly re-enable the hardware before saving.
1602 	 */
1603 
1604 	preempt_disable();
1605 	if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) {
1606 		if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) {
1607 			set_c0_config5(MIPS_CONF5_MSAEN);
1608 			enable_fpu_hazard();
1609 		}
1610 
1611 		__kvm_save_msa(&vcpu->arch);
1612 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU_MSA);
1613 
1614 		/* Disable MSA & FPU */
1615 		disable_msa();
1616 		if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1617 			clear_c0_status(ST0_CU1 | ST0_FR);
1618 			disable_fpu_hazard();
1619 		}
1620 		vcpu->arch.aux_inuse &= ~(KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA);
1621 	} else if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
1622 		if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) {
1623 			set_c0_status(ST0_CU1);
1624 			enable_fpu_hazard();
1625 		}
1626 
1627 		__kvm_save_fpu(&vcpu->arch);
1628 		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
1629 		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU);
1630 
1631 		/* Disable FPU */
1632 		clear_c0_status(ST0_CU1 | ST0_FR);
1633 		disable_fpu_hazard();
1634 	}
1635 	preempt_enable();
1636 }
1637 
1638 /*
1639  * Step over a specific ctc1 to FCSR and a specific ctcmsa to MSACSR which are
1640  * used to restore guest FCSR/MSACSR state and may trigger a "harmless" FP/MSAFP
1641  * exception if cause bits are set in the value being written.
1642  */
1643 static int kvm_mips_csr_die_notify(struct notifier_block *self,
1644 				   unsigned long cmd, void *ptr)
1645 {
1646 	struct die_args *args = (struct die_args *)ptr;
1647 	struct pt_regs *regs = args->regs;
1648 	unsigned long pc;
1649 
1650 	/* Only interested in FPE and MSAFPE */
1651 	if (cmd != DIE_FP && cmd != DIE_MSAFP)
1652 		return NOTIFY_DONE;
1653 
1654 	/* Return immediately if guest context isn't active */
1655 	if (!(current->flags & PF_VCPU))
1656 		return NOTIFY_DONE;
1657 
1658 	/* Should never get here from user mode */
1659 	BUG_ON(user_mode(regs));
1660 
1661 	pc = instruction_pointer(regs);
1662 	switch (cmd) {
1663 	case DIE_FP:
1664 		/* match 2nd instruction in __kvm_restore_fcsr */
1665 		if (pc != (unsigned long)&__kvm_restore_fcsr + 4)
1666 			return NOTIFY_DONE;
1667 		break;
1668 	case DIE_MSAFP:
1669 		/* match 2nd/3rd instruction in __kvm_restore_msacsr */
1670 		if (!cpu_has_msa ||
1671 		    pc < (unsigned long)&__kvm_restore_msacsr + 4 ||
1672 		    pc > (unsigned long)&__kvm_restore_msacsr + 8)
1673 			return NOTIFY_DONE;
1674 		break;
1675 	}
1676 
1677 	/* Move PC forward a little and continue executing */
1678 	instruction_pointer(regs) += 4;
1679 
1680 	return NOTIFY_STOP;
1681 }
1682 
1683 static struct notifier_block kvm_mips_csr_die_notifier = {
1684 	.notifier_call = kvm_mips_csr_die_notify,
1685 };
1686 
1687 static int __init kvm_mips_init(void)
1688 {
1689 	int ret;
1690 
1691 	if (cpu_has_mmid) {
1692 		pr_warn("KVM does not yet support MMIDs. KVM Disabled\n");
1693 		return -EOPNOTSUPP;
1694 	}
1695 
1696 	ret = kvm_mips_entry_setup();
1697 	if (ret)
1698 		return ret;
1699 
1700 	ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
1701 
1702 	if (ret)
1703 		return ret;
1704 
1705 	register_die_notifier(&kvm_mips_csr_die_notifier);
1706 
1707 	return 0;
1708 }
1709 
1710 static void __exit kvm_mips_exit(void)
1711 {
1712 	kvm_exit();
1713 
1714 	unregister_die_notifier(&kvm_mips_csr_die_notifier);
1715 }
1716 
1717 module_init(kvm_mips_init);
1718 module_exit(kvm_mips_exit);
1719 
1720 EXPORT_TRACEPOINT_SYMBOL(kvm_exit);
1721