xref: /openbmc/linux/arch/mips/kvm/mips.c (revision 77a87824)
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/errno.h>
13 #include <linux/err.h>
14 #include <linux/kdebug.h>
15 #include <linux/module.h>
16 #include <linux/vmalloc.h>
17 #include <linux/fs.h>
18 #include <linux/bootmem.h>
19 #include <asm/fpu.h>
20 #include <asm/page.h>
21 #include <asm/cacheflush.h>
22 #include <asm/mmu_context.h>
23 #include <asm/pgtable.h>
24 
25 #include <linux/kvm_host.h>
26 
27 #include "interrupt.h"
28 #include "commpage.h"
29 
30 #define CREATE_TRACE_POINTS
31 #include "trace.h"
32 
33 #ifndef VECTORSPACING
34 #define VECTORSPACING 0x100	/* for EI/VI mode */
35 #endif
36 
37 #define VCPU_STAT(x) offsetof(struct kvm_vcpu, stat.x)
38 struct kvm_stats_debugfs_item debugfs_entries[] = {
39 	{ "wait",	  VCPU_STAT(wait_exits),	 KVM_STAT_VCPU },
40 	{ "cache",	  VCPU_STAT(cache_exits),	 KVM_STAT_VCPU },
41 	{ "signal",	  VCPU_STAT(signal_exits),	 KVM_STAT_VCPU },
42 	{ "interrupt",	  VCPU_STAT(int_exits),		 KVM_STAT_VCPU },
43 	{ "cop_unsuable", VCPU_STAT(cop_unusable_exits), KVM_STAT_VCPU },
44 	{ "tlbmod",	  VCPU_STAT(tlbmod_exits),	 KVM_STAT_VCPU },
45 	{ "tlbmiss_ld",	  VCPU_STAT(tlbmiss_ld_exits),	 KVM_STAT_VCPU },
46 	{ "tlbmiss_st",	  VCPU_STAT(tlbmiss_st_exits),	 KVM_STAT_VCPU },
47 	{ "addrerr_st",	  VCPU_STAT(addrerr_st_exits),	 KVM_STAT_VCPU },
48 	{ "addrerr_ld",	  VCPU_STAT(addrerr_ld_exits),	 KVM_STAT_VCPU },
49 	{ "syscall",	  VCPU_STAT(syscall_exits),	 KVM_STAT_VCPU },
50 	{ "resvd_inst",	  VCPU_STAT(resvd_inst_exits),	 KVM_STAT_VCPU },
51 	{ "break_inst",	  VCPU_STAT(break_inst_exits),	 KVM_STAT_VCPU },
52 	{ "trap_inst",	  VCPU_STAT(trap_inst_exits),	 KVM_STAT_VCPU },
53 	{ "msa_fpe",	  VCPU_STAT(msa_fpe_exits),	 KVM_STAT_VCPU },
54 	{ "fpe",	  VCPU_STAT(fpe_exits),		 KVM_STAT_VCPU },
55 	{ "msa_disabled", VCPU_STAT(msa_disabled_exits), KVM_STAT_VCPU },
56 	{ "flush_dcache", VCPU_STAT(flush_dcache_exits), KVM_STAT_VCPU },
57 	{ "halt_successful_poll", VCPU_STAT(halt_successful_poll), KVM_STAT_VCPU },
58 	{ "halt_attempted_poll", VCPU_STAT(halt_attempted_poll), KVM_STAT_VCPU },
59 	{ "halt_poll_invalid", VCPU_STAT(halt_poll_invalid), KVM_STAT_VCPU },
60 	{ "halt_wakeup",  VCPU_STAT(halt_wakeup),	 KVM_STAT_VCPU },
61 	{NULL}
62 };
63 
64 static int kvm_mips_reset_vcpu(struct kvm_vcpu *vcpu)
65 {
66 	int i;
67 
68 	for_each_possible_cpu(i) {
69 		vcpu->arch.guest_kernel_asid[i] = 0;
70 		vcpu->arch.guest_user_asid[i] = 0;
71 	}
72 
73 	return 0;
74 }
75 
76 /*
77  * XXXKYMA: We are simulatoring a processor that has the WII bit set in
78  * Config7, so we are "runnable" if interrupts are pending
79  */
80 int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
81 {
82 	return !!(vcpu->arch.pending_exceptions);
83 }
84 
85 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
86 {
87 	return 1;
88 }
89 
90 int kvm_arch_hardware_enable(void)
91 {
92 	return 0;
93 }
94 
95 int kvm_arch_hardware_setup(void)
96 {
97 	return 0;
98 }
99 
100 void kvm_arch_check_processor_compat(void *rtn)
101 {
102 	*(int *)rtn = 0;
103 }
104 
105 static void kvm_mips_init_tlbs(struct kvm *kvm)
106 {
107 	unsigned long wired;
108 
109 	/*
110 	 * Add a wired entry to the TLB, it is used to map the commpage to
111 	 * the Guest kernel
112 	 */
113 	wired = read_c0_wired();
114 	write_c0_wired(wired + 1);
115 	mtc0_tlbw_hazard();
116 	kvm->arch.commpage_tlb = wired;
117 
118 	kvm_debug("[%d] commpage TLB: %d\n", smp_processor_id(),
119 		  kvm->arch.commpage_tlb);
120 }
121 
122 static void kvm_mips_init_vm_percpu(void *arg)
123 {
124 	struct kvm *kvm = (struct kvm *)arg;
125 
126 	kvm_mips_init_tlbs(kvm);
127 	kvm_mips_callbacks->vm_init(kvm);
128 
129 }
130 
131 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
132 {
133 	if (atomic_inc_return(&kvm_mips_instance) == 1) {
134 		kvm_debug("%s: 1st KVM instance, setup host TLB parameters\n",
135 			  __func__);
136 		on_each_cpu(kvm_mips_init_vm_percpu, kvm, 1);
137 	}
138 
139 	return 0;
140 }
141 
142 void kvm_mips_free_vcpus(struct kvm *kvm)
143 {
144 	unsigned int i;
145 	struct kvm_vcpu *vcpu;
146 
147 	/* Put the pages we reserved for the guest pmap */
148 	for (i = 0; i < kvm->arch.guest_pmap_npages; i++) {
149 		if (kvm->arch.guest_pmap[i] != KVM_INVALID_PAGE)
150 			kvm_mips_release_pfn_clean(kvm->arch.guest_pmap[i]);
151 	}
152 	kfree(kvm->arch.guest_pmap);
153 
154 	kvm_for_each_vcpu(i, vcpu, kvm) {
155 		kvm_arch_vcpu_free(vcpu);
156 	}
157 
158 	mutex_lock(&kvm->lock);
159 
160 	for (i = 0; i < atomic_read(&kvm->online_vcpus); i++)
161 		kvm->vcpus[i] = NULL;
162 
163 	atomic_set(&kvm->online_vcpus, 0);
164 
165 	mutex_unlock(&kvm->lock);
166 }
167 
168 static void kvm_mips_uninit_tlbs(void *arg)
169 {
170 	/* Restore wired count */
171 	write_c0_wired(0);
172 	mtc0_tlbw_hazard();
173 	/* Clear out all the TLBs */
174 	kvm_local_flush_tlb_all();
175 }
176 
177 void kvm_arch_destroy_vm(struct kvm *kvm)
178 {
179 	kvm_mips_free_vcpus(kvm);
180 
181 	/* If this is the last instance, restore wired count */
182 	if (atomic_dec_return(&kvm_mips_instance) == 0) {
183 		kvm_debug("%s: last KVM instance, restoring TLB parameters\n",
184 			  __func__);
185 		on_each_cpu(kvm_mips_uninit_tlbs, NULL, 1);
186 	}
187 }
188 
189 long kvm_arch_dev_ioctl(struct file *filp, unsigned int ioctl,
190 			unsigned long arg)
191 {
192 	return -ENOIOCTLCMD;
193 }
194 
195 int kvm_arch_create_memslot(struct kvm *kvm, struct kvm_memory_slot *slot,
196 			    unsigned long npages)
197 {
198 	return 0;
199 }
200 
201 int kvm_arch_prepare_memory_region(struct kvm *kvm,
202 				   struct kvm_memory_slot *memslot,
203 				   const struct kvm_userspace_memory_region *mem,
204 				   enum kvm_mr_change change)
205 {
206 	return 0;
207 }
208 
209 void kvm_arch_commit_memory_region(struct kvm *kvm,
210 				   const struct kvm_userspace_memory_region *mem,
211 				   const struct kvm_memory_slot *old,
212 				   const struct kvm_memory_slot *new,
213 				   enum kvm_mr_change change)
214 {
215 	unsigned long npages = 0;
216 	int i;
217 
218 	kvm_debug("%s: kvm: %p slot: %d, GPA: %llx, size: %llx, QVA: %llx\n",
219 		  __func__, kvm, mem->slot, mem->guest_phys_addr,
220 		  mem->memory_size, mem->userspace_addr);
221 
222 	/* Setup Guest PMAP table */
223 	if (!kvm->arch.guest_pmap) {
224 		if (mem->slot == 0)
225 			npages = mem->memory_size >> PAGE_SHIFT;
226 
227 		if (npages) {
228 			kvm->arch.guest_pmap_npages = npages;
229 			kvm->arch.guest_pmap =
230 			    kzalloc(npages * sizeof(unsigned long), GFP_KERNEL);
231 
232 			if (!kvm->arch.guest_pmap) {
233 				kvm_err("Failed to allocate guest PMAP\n");
234 				return;
235 			}
236 
237 			kvm_debug("Allocated space for Guest PMAP Table (%ld pages) @ %p\n",
238 				  npages, kvm->arch.guest_pmap);
239 
240 			/* Now setup the page table */
241 			for (i = 0; i < npages; i++)
242 				kvm->arch.guest_pmap[i] = KVM_INVALID_PAGE;
243 		}
244 	}
245 }
246 
247 struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
248 {
249 	int err, size, offset;
250 	void *gebase;
251 	int i;
252 
253 	struct kvm_vcpu *vcpu = kzalloc(sizeof(struct kvm_vcpu), GFP_KERNEL);
254 
255 	if (!vcpu) {
256 		err = -ENOMEM;
257 		goto out;
258 	}
259 
260 	err = kvm_vcpu_init(vcpu, kvm, id);
261 
262 	if (err)
263 		goto out_free_cpu;
264 
265 	kvm_debug("kvm @ %p: create cpu %d at %p\n", kvm, id, vcpu);
266 
267 	/*
268 	 * Allocate space for host mode exception handlers that handle
269 	 * guest mode exits
270 	 */
271 	if (cpu_has_veic || cpu_has_vint)
272 		size = 0x200 + VECTORSPACING * 64;
273 	else
274 		size = 0x4000;
275 
276 	/* Save Linux EBASE */
277 	vcpu->arch.host_ebase = (void *)read_c0_ebase();
278 
279 	gebase = kzalloc(ALIGN(size, PAGE_SIZE), GFP_KERNEL);
280 
281 	if (!gebase) {
282 		err = -ENOMEM;
283 		goto out_uninit_cpu;
284 	}
285 	kvm_debug("Allocated %d bytes for KVM Exception Handlers @ %p\n",
286 		  ALIGN(size, PAGE_SIZE), gebase);
287 
288 	/* Save new ebase */
289 	vcpu->arch.guest_ebase = gebase;
290 
291 	/* Copy L1 Guest Exception handler to correct offset */
292 
293 	/* TLB Refill, EXL = 0 */
294 	memcpy(gebase, mips32_exception,
295 	       mips32_exceptionEnd - mips32_exception);
296 
297 	/* General Exception Entry point */
298 	memcpy(gebase + 0x180, mips32_exception,
299 	       mips32_exceptionEnd - mips32_exception);
300 
301 	/* For vectored interrupts poke the exception code @ all offsets 0-7 */
302 	for (i = 0; i < 8; i++) {
303 		kvm_debug("L1 Vectored handler @ %p\n",
304 			  gebase + 0x200 + (i * VECTORSPACING));
305 		memcpy(gebase + 0x200 + (i * VECTORSPACING), mips32_exception,
306 		       mips32_exceptionEnd - mips32_exception);
307 	}
308 
309 	/* General handler, relocate to unmapped space for sanity's sake */
310 	offset = 0x2000;
311 	kvm_debug("Installing KVM Exception handlers @ %p, %#x bytes\n",
312 		  gebase + offset,
313 		  mips32_GuestExceptionEnd - mips32_GuestException);
314 
315 	memcpy(gebase + offset, mips32_GuestException,
316 	       mips32_GuestExceptionEnd - mips32_GuestException);
317 
318 #ifdef MODULE
319 	offset += mips32_GuestExceptionEnd - mips32_GuestException;
320 	memcpy(gebase + offset, (char *)__kvm_mips_vcpu_run,
321 	       __kvm_mips_vcpu_run_end - (char *)__kvm_mips_vcpu_run);
322 	vcpu->arch.vcpu_run = gebase + offset;
323 #else
324 	vcpu->arch.vcpu_run = __kvm_mips_vcpu_run;
325 #endif
326 
327 	/* Invalidate the icache for these ranges */
328 	local_flush_icache_range((unsigned long)gebase,
329 				(unsigned long)gebase + ALIGN(size, PAGE_SIZE));
330 
331 	/*
332 	 * Allocate comm page for guest kernel, a TLB will be reserved for
333 	 * mapping GVA @ 0xFFFF8000 to this page
334 	 */
335 	vcpu->arch.kseg0_commpage = kzalloc(PAGE_SIZE << 1, GFP_KERNEL);
336 
337 	if (!vcpu->arch.kseg0_commpage) {
338 		err = -ENOMEM;
339 		goto out_free_gebase;
340 	}
341 
342 	kvm_debug("Allocated COMM page @ %p\n", vcpu->arch.kseg0_commpage);
343 	kvm_mips_commpage_init(vcpu);
344 
345 	/* Init */
346 	vcpu->arch.last_sched_cpu = -1;
347 
348 	/* Start off the timer */
349 	kvm_mips_init_count(vcpu);
350 
351 	return vcpu;
352 
353 out_free_gebase:
354 	kfree(gebase);
355 
356 out_uninit_cpu:
357 	kvm_vcpu_uninit(vcpu);
358 
359 out_free_cpu:
360 	kfree(vcpu);
361 
362 out:
363 	return ERR_PTR(err);
364 }
365 
366 void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
367 {
368 	hrtimer_cancel(&vcpu->arch.comparecount_timer);
369 
370 	kvm_vcpu_uninit(vcpu);
371 
372 	kvm_mips_dump_stats(vcpu);
373 
374 	kfree(vcpu->arch.guest_ebase);
375 	kfree(vcpu->arch.kseg0_commpage);
376 	kfree(vcpu);
377 }
378 
379 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
380 {
381 	kvm_arch_vcpu_free(vcpu);
382 }
383 
384 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
385 					struct kvm_guest_debug *dbg)
386 {
387 	return -ENOIOCTLCMD;
388 }
389 
390 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
391 {
392 	int r = 0;
393 	sigset_t sigsaved;
394 
395 	if (vcpu->sigset_active)
396 		sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);
397 
398 	if (vcpu->mmio_needed) {
399 		if (!vcpu->mmio_is_write)
400 			kvm_mips_complete_mmio_load(vcpu, run);
401 		vcpu->mmio_needed = 0;
402 	}
403 
404 	lose_fpu(1);
405 
406 	local_irq_disable();
407 	/* Check if we have any exceptions/interrupts pending */
408 	kvm_mips_deliver_interrupts(vcpu,
409 				    kvm_read_c0_guest_cause(vcpu->arch.cop0));
410 
411 	__kvm_guest_enter();
412 
413 	/* Disable hardware page table walking while in guest */
414 	htw_stop();
415 
416 	r = vcpu->arch.vcpu_run(run, vcpu);
417 
418 	/* Re-enable HTW before enabling interrupts */
419 	htw_start();
420 
421 	__kvm_guest_exit();
422 	local_irq_enable();
423 
424 	if (vcpu->sigset_active)
425 		sigprocmask(SIG_SETMASK, &sigsaved, NULL);
426 
427 	return r;
428 }
429 
430 int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
431 			     struct kvm_mips_interrupt *irq)
432 {
433 	int intr = (int)irq->irq;
434 	struct kvm_vcpu *dvcpu = NULL;
435 
436 	if (intr == 3 || intr == -3 || intr == 4 || intr == -4)
437 		kvm_debug("%s: CPU: %d, INTR: %d\n", __func__, irq->cpu,
438 			  (int)intr);
439 
440 	if (irq->cpu == -1)
441 		dvcpu = vcpu;
442 	else
443 		dvcpu = vcpu->kvm->vcpus[irq->cpu];
444 
445 	if (intr == 2 || intr == 3 || intr == 4) {
446 		kvm_mips_callbacks->queue_io_int(dvcpu, irq);
447 
448 	} else if (intr == -2 || intr == -3 || intr == -4) {
449 		kvm_mips_callbacks->dequeue_io_int(dvcpu, irq);
450 	} else {
451 		kvm_err("%s: invalid interrupt ioctl (%d:%d)\n", __func__,
452 			irq->cpu, irq->irq);
453 		return -EINVAL;
454 	}
455 
456 	dvcpu->arch.wait = 0;
457 
458 	if (swait_active(&dvcpu->wq))
459 		swake_up(&dvcpu->wq);
460 
461 	return 0;
462 }
463 
464 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
465 				    struct kvm_mp_state *mp_state)
466 {
467 	return -ENOIOCTLCMD;
468 }
469 
470 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
471 				    struct kvm_mp_state *mp_state)
472 {
473 	return -ENOIOCTLCMD;
474 }
475 
476 static u64 kvm_mips_get_one_regs[] = {
477 	KVM_REG_MIPS_R0,
478 	KVM_REG_MIPS_R1,
479 	KVM_REG_MIPS_R2,
480 	KVM_REG_MIPS_R3,
481 	KVM_REG_MIPS_R4,
482 	KVM_REG_MIPS_R5,
483 	KVM_REG_MIPS_R6,
484 	KVM_REG_MIPS_R7,
485 	KVM_REG_MIPS_R8,
486 	KVM_REG_MIPS_R9,
487 	KVM_REG_MIPS_R10,
488 	KVM_REG_MIPS_R11,
489 	KVM_REG_MIPS_R12,
490 	KVM_REG_MIPS_R13,
491 	KVM_REG_MIPS_R14,
492 	KVM_REG_MIPS_R15,
493 	KVM_REG_MIPS_R16,
494 	KVM_REG_MIPS_R17,
495 	KVM_REG_MIPS_R18,
496 	KVM_REG_MIPS_R19,
497 	KVM_REG_MIPS_R20,
498 	KVM_REG_MIPS_R21,
499 	KVM_REG_MIPS_R22,
500 	KVM_REG_MIPS_R23,
501 	KVM_REG_MIPS_R24,
502 	KVM_REG_MIPS_R25,
503 	KVM_REG_MIPS_R26,
504 	KVM_REG_MIPS_R27,
505 	KVM_REG_MIPS_R28,
506 	KVM_REG_MIPS_R29,
507 	KVM_REG_MIPS_R30,
508 	KVM_REG_MIPS_R31,
509 
510 	KVM_REG_MIPS_HI,
511 	KVM_REG_MIPS_LO,
512 	KVM_REG_MIPS_PC,
513 
514 	KVM_REG_MIPS_CP0_INDEX,
515 	KVM_REG_MIPS_CP0_CONTEXT,
516 	KVM_REG_MIPS_CP0_USERLOCAL,
517 	KVM_REG_MIPS_CP0_PAGEMASK,
518 	KVM_REG_MIPS_CP0_WIRED,
519 	KVM_REG_MIPS_CP0_HWRENA,
520 	KVM_REG_MIPS_CP0_BADVADDR,
521 	KVM_REG_MIPS_CP0_COUNT,
522 	KVM_REG_MIPS_CP0_ENTRYHI,
523 	KVM_REG_MIPS_CP0_COMPARE,
524 	KVM_REG_MIPS_CP0_STATUS,
525 	KVM_REG_MIPS_CP0_CAUSE,
526 	KVM_REG_MIPS_CP0_EPC,
527 	KVM_REG_MIPS_CP0_PRID,
528 	KVM_REG_MIPS_CP0_CONFIG,
529 	KVM_REG_MIPS_CP0_CONFIG1,
530 	KVM_REG_MIPS_CP0_CONFIG2,
531 	KVM_REG_MIPS_CP0_CONFIG3,
532 	KVM_REG_MIPS_CP0_CONFIG4,
533 	KVM_REG_MIPS_CP0_CONFIG5,
534 	KVM_REG_MIPS_CP0_CONFIG7,
535 	KVM_REG_MIPS_CP0_ERROREPC,
536 
537 	KVM_REG_MIPS_COUNT_CTL,
538 	KVM_REG_MIPS_COUNT_RESUME,
539 	KVM_REG_MIPS_COUNT_HZ,
540 };
541 
542 static int kvm_mips_get_reg(struct kvm_vcpu *vcpu,
543 			    const struct kvm_one_reg *reg)
544 {
545 	struct mips_coproc *cop0 = vcpu->arch.cop0;
546 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
547 	int ret;
548 	s64 v;
549 	s64 vs[2];
550 	unsigned int idx;
551 
552 	switch (reg->id) {
553 	/* General purpose registers */
554 	case KVM_REG_MIPS_R0 ... KVM_REG_MIPS_R31:
555 		v = (long)vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0];
556 		break;
557 	case KVM_REG_MIPS_HI:
558 		v = (long)vcpu->arch.hi;
559 		break;
560 	case KVM_REG_MIPS_LO:
561 		v = (long)vcpu->arch.lo;
562 		break;
563 	case KVM_REG_MIPS_PC:
564 		v = (long)vcpu->arch.pc;
565 		break;
566 
567 	/* Floating point registers */
568 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
569 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
570 			return -EINVAL;
571 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
572 		/* Odd singles in top of even double when FR=0 */
573 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
574 			v = get_fpr32(&fpu->fpr[idx], 0);
575 		else
576 			v = get_fpr32(&fpu->fpr[idx & ~1], idx & 1);
577 		break;
578 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
579 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
580 			return -EINVAL;
581 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
582 		/* Can't access odd doubles in FR=0 mode */
583 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
584 			return -EINVAL;
585 		v = get_fpr64(&fpu->fpr[idx], 0);
586 		break;
587 	case KVM_REG_MIPS_FCR_IR:
588 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
589 			return -EINVAL;
590 		v = boot_cpu_data.fpu_id;
591 		break;
592 	case KVM_REG_MIPS_FCR_CSR:
593 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
594 			return -EINVAL;
595 		v = fpu->fcr31;
596 		break;
597 
598 	/* MIPS SIMD Architecture (MSA) registers */
599 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
600 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
601 			return -EINVAL;
602 		/* Can't access MSA registers in FR=0 mode */
603 		if (!(kvm_read_c0_guest_status(cop0) & ST0_FR))
604 			return -EINVAL;
605 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
606 #ifdef CONFIG_CPU_LITTLE_ENDIAN
607 		/* least significant byte first */
608 		vs[0] = get_fpr64(&fpu->fpr[idx], 0);
609 		vs[1] = get_fpr64(&fpu->fpr[idx], 1);
610 #else
611 		/* most significant byte first */
612 		vs[0] = get_fpr64(&fpu->fpr[idx], 1);
613 		vs[1] = get_fpr64(&fpu->fpr[idx], 0);
614 #endif
615 		break;
616 	case KVM_REG_MIPS_MSA_IR:
617 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
618 			return -EINVAL;
619 		v = boot_cpu_data.msa_id;
620 		break;
621 	case KVM_REG_MIPS_MSA_CSR:
622 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
623 			return -EINVAL;
624 		v = fpu->msacsr;
625 		break;
626 
627 	/* Co-processor 0 registers */
628 	case KVM_REG_MIPS_CP0_INDEX:
629 		v = (long)kvm_read_c0_guest_index(cop0);
630 		break;
631 	case KVM_REG_MIPS_CP0_CONTEXT:
632 		v = (long)kvm_read_c0_guest_context(cop0);
633 		break;
634 	case KVM_REG_MIPS_CP0_USERLOCAL:
635 		v = (long)kvm_read_c0_guest_userlocal(cop0);
636 		break;
637 	case KVM_REG_MIPS_CP0_PAGEMASK:
638 		v = (long)kvm_read_c0_guest_pagemask(cop0);
639 		break;
640 	case KVM_REG_MIPS_CP0_WIRED:
641 		v = (long)kvm_read_c0_guest_wired(cop0);
642 		break;
643 	case KVM_REG_MIPS_CP0_HWRENA:
644 		v = (long)kvm_read_c0_guest_hwrena(cop0);
645 		break;
646 	case KVM_REG_MIPS_CP0_BADVADDR:
647 		v = (long)kvm_read_c0_guest_badvaddr(cop0);
648 		break;
649 	case KVM_REG_MIPS_CP0_ENTRYHI:
650 		v = (long)kvm_read_c0_guest_entryhi(cop0);
651 		break;
652 	case KVM_REG_MIPS_CP0_COMPARE:
653 		v = (long)kvm_read_c0_guest_compare(cop0);
654 		break;
655 	case KVM_REG_MIPS_CP0_STATUS:
656 		v = (long)kvm_read_c0_guest_status(cop0);
657 		break;
658 	case KVM_REG_MIPS_CP0_CAUSE:
659 		v = (long)kvm_read_c0_guest_cause(cop0);
660 		break;
661 	case KVM_REG_MIPS_CP0_EPC:
662 		v = (long)kvm_read_c0_guest_epc(cop0);
663 		break;
664 	case KVM_REG_MIPS_CP0_PRID:
665 		v = (long)kvm_read_c0_guest_prid(cop0);
666 		break;
667 	case KVM_REG_MIPS_CP0_CONFIG:
668 		v = (long)kvm_read_c0_guest_config(cop0);
669 		break;
670 	case KVM_REG_MIPS_CP0_CONFIG1:
671 		v = (long)kvm_read_c0_guest_config1(cop0);
672 		break;
673 	case KVM_REG_MIPS_CP0_CONFIG2:
674 		v = (long)kvm_read_c0_guest_config2(cop0);
675 		break;
676 	case KVM_REG_MIPS_CP0_CONFIG3:
677 		v = (long)kvm_read_c0_guest_config3(cop0);
678 		break;
679 	case KVM_REG_MIPS_CP0_CONFIG4:
680 		v = (long)kvm_read_c0_guest_config4(cop0);
681 		break;
682 	case KVM_REG_MIPS_CP0_CONFIG5:
683 		v = (long)kvm_read_c0_guest_config5(cop0);
684 		break;
685 	case KVM_REG_MIPS_CP0_CONFIG7:
686 		v = (long)kvm_read_c0_guest_config7(cop0);
687 		break;
688 	case KVM_REG_MIPS_CP0_ERROREPC:
689 		v = (long)kvm_read_c0_guest_errorepc(cop0);
690 		break;
691 	/* registers to be handled specially */
692 	case KVM_REG_MIPS_CP0_COUNT:
693 	case KVM_REG_MIPS_COUNT_CTL:
694 	case KVM_REG_MIPS_COUNT_RESUME:
695 	case KVM_REG_MIPS_COUNT_HZ:
696 		ret = kvm_mips_callbacks->get_one_reg(vcpu, reg, &v);
697 		if (ret)
698 			return ret;
699 		break;
700 	default:
701 		return -EINVAL;
702 	}
703 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
704 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
705 
706 		return put_user(v, uaddr64);
707 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
708 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
709 		u32 v32 = (u32)v;
710 
711 		return put_user(v32, uaddr32);
712 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
713 		void __user *uaddr = (void __user *)(long)reg->addr;
714 
715 		return copy_to_user(uaddr, vs, 16) ? -EFAULT : 0;
716 	} else {
717 		return -EINVAL;
718 	}
719 }
720 
721 static int kvm_mips_set_reg(struct kvm_vcpu *vcpu,
722 			    const struct kvm_one_reg *reg)
723 {
724 	struct mips_coproc *cop0 = vcpu->arch.cop0;
725 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
726 	s64 v;
727 	s64 vs[2];
728 	unsigned int idx;
729 
730 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
731 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
732 
733 		if (get_user(v, uaddr64) != 0)
734 			return -EFAULT;
735 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
736 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
737 		s32 v32;
738 
739 		if (get_user(v32, uaddr32) != 0)
740 			return -EFAULT;
741 		v = (s64)v32;
742 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
743 		void __user *uaddr = (void __user *)(long)reg->addr;
744 
745 		return copy_from_user(vs, uaddr, 16) ? -EFAULT : 0;
746 	} else {
747 		return -EINVAL;
748 	}
749 
750 	switch (reg->id) {
751 	/* General purpose registers */
752 	case KVM_REG_MIPS_R0:
753 		/* Silently ignore requests to set $0 */
754 		break;
755 	case KVM_REG_MIPS_R1 ... KVM_REG_MIPS_R31:
756 		vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0] = v;
757 		break;
758 	case KVM_REG_MIPS_HI:
759 		vcpu->arch.hi = v;
760 		break;
761 	case KVM_REG_MIPS_LO:
762 		vcpu->arch.lo = v;
763 		break;
764 	case KVM_REG_MIPS_PC:
765 		vcpu->arch.pc = v;
766 		break;
767 
768 	/* Floating point registers */
769 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
770 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
771 			return -EINVAL;
772 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
773 		/* Odd singles in top of even double when FR=0 */
774 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
775 			set_fpr32(&fpu->fpr[idx], 0, v);
776 		else
777 			set_fpr32(&fpu->fpr[idx & ~1], idx & 1, v);
778 		break;
779 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
780 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
781 			return -EINVAL;
782 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
783 		/* Can't access odd doubles in FR=0 mode */
784 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
785 			return -EINVAL;
786 		set_fpr64(&fpu->fpr[idx], 0, v);
787 		break;
788 	case KVM_REG_MIPS_FCR_IR:
789 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
790 			return -EINVAL;
791 		/* Read-only */
792 		break;
793 	case KVM_REG_MIPS_FCR_CSR:
794 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
795 			return -EINVAL;
796 		fpu->fcr31 = v;
797 		break;
798 
799 	/* MIPS SIMD Architecture (MSA) registers */
800 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
801 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
802 			return -EINVAL;
803 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
804 #ifdef CONFIG_CPU_LITTLE_ENDIAN
805 		/* least significant byte first */
806 		set_fpr64(&fpu->fpr[idx], 0, vs[0]);
807 		set_fpr64(&fpu->fpr[idx], 1, vs[1]);
808 #else
809 		/* most significant byte first */
810 		set_fpr64(&fpu->fpr[idx], 1, vs[0]);
811 		set_fpr64(&fpu->fpr[idx], 0, vs[1]);
812 #endif
813 		break;
814 	case KVM_REG_MIPS_MSA_IR:
815 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
816 			return -EINVAL;
817 		/* Read-only */
818 		break;
819 	case KVM_REG_MIPS_MSA_CSR:
820 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
821 			return -EINVAL;
822 		fpu->msacsr = v;
823 		break;
824 
825 	/* Co-processor 0 registers */
826 	case KVM_REG_MIPS_CP0_INDEX:
827 		kvm_write_c0_guest_index(cop0, v);
828 		break;
829 	case KVM_REG_MIPS_CP0_CONTEXT:
830 		kvm_write_c0_guest_context(cop0, v);
831 		break;
832 	case KVM_REG_MIPS_CP0_USERLOCAL:
833 		kvm_write_c0_guest_userlocal(cop0, v);
834 		break;
835 	case KVM_REG_MIPS_CP0_PAGEMASK:
836 		kvm_write_c0_guest_pagemask(cop0, v);
837 		break;
838 	case KVM_REG_MIPS_CP0_WIRED:
839 		kvm_write_c0_guest_wired(cop0, v);
840 		break;
841 	case KVM_REG_MIPS_CP0_HWRENA:
842 		kvm_write_c0_guest_hwrena(cop0, v);
843 		break;
844 	case KVM_REG_MIPS_CP0_BADVADDR:
845 		kvm_write_c0_guest_badvaddr(cop0, v);
846 		break;
847 	case KVM_REG_MIPS_CP0_ENTRYHI:
848 		kvm_write_c0_guest_entryhi(cop0, v);
849 		break;
850 	case KVM_REG_MIPS_CP0_STATUS:
851 		kvm_write_c0_guest_status(cop0, v);
852 		break;
853 	case KVM_REG_MIPS_CP0_EPC:
854 		kvm_write_c0_guest_epc(cop0, v);
855 		break;
856 	case KVM_REG_MIPS_CP0_PRID:
857 		kvm_write_c0_guest_prid(cop0, v);
858 		break;
859 	case KVM_REG_MIPS_CP0_ERROREPC:
860 		kvm_write_c0_guest_errorepc(cop0, v);
861 		break;
862 	/* registers to be handled specially */
863 	case KVM_REG_MIPS_CP0_COUNT:
864 	case KVM_REG_MIPS_CP0_COMPARE:
865 	case KVM_REG_MIPS_CP0_CAUSE:
866 	case KVM_REG_MIPS_CP0_CONFIG:
867 	case KVM_REG_MIPS_CP0_CONFIG1:
868 	case KVM_REG_MIPS_CP0_CONFIG2:
869 	case KVM_REG_MIPS_CP0_CONFIG3:
870 	case KVM_REG_MIPS_CP0_CONFIG4:
871 	case KVM_REG_MIPS_CP0_CONFIG5:
872 	case KVM_REG_MIPS_COUNT_CTL:
873 	case KVM_REG_MIPS_COUNT_RESUME:
874 	case KVM_REG_MIPS_COUNT_HZ:
875 		return kvm_mips_callbacks->set_one_reg(vcpu, reg, v);
876 	default:
877 		return -EINVAL;
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_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 	long r;
915 
916 	switch (ioctl) {
917 	case KVM_SET_ONE_REG:
918 	case KVM_GET_ONE_REG: {
919 		struct kvm_one_reg reg;
920 
921 		if (copy_from_user(&reg, argp, sizeof(reg)))
922 			return -EFAULT;
923 		if (ioctl == KVM_SET_ONE_REG)
924 			return kvm_mips_set_reg(vcpu, &reg);
925 		else
926 			return kvm_mips_get_reg(vcpu, &reg);
927 	}
928 	case KVM_GET_REG_LIST: {
929 		struct kvm_reg_list __user *user_list = argp;
930 		u64 __user *reg_dest;
931 		struct kvm_reg_list reg_list;
932 		unsigned n;
933 
934 		if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
935 			return -EFAULT;
936 		n = reg_list.n;
937 		reg_list.n = ARRAY_SIZE(kvm_mips_get_one_regs);
938 		if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
939 			return -EFAULT;
940 		if (n < reg_list.n)
941 			return -E2BIG;
942 		reg_dest = user_list->reg;
943 		if (copy_to_user(reg_dest, kvm_mips_get_one_regs,
944 				 sizeof(kvm_mips_get_one_regs)))
945 			return -EFAULT;
946 		return 0;
947 	}
948 	case KVM_NMI:
949 		/* Treat the NMI as a CPU reset */
950 		r = kvm_mips_reset_vcpu(vcpu);
951 		break;
952 	case KVM_INTERRUPT:
953 		{
954 			struct kvm_mips_interrupt irq;
955 
956 			r = -EFAULT;
957 			if (copy_from_user(&irq, argp, sizeof(irq)))
958 				goto out;
959 
960 			kvm_debug("[%d] %s: irq: %d\n", vcpu->vcpu_id, __func__,
961 				  irq.irq);
962 
963 			r = kvm_vcpu_ioctl_interrupt(vcpu, &irq);
964 			break;
965 		}
966 	case KVM_ENABLE_CAP: {
967 		struct kvm_enable_cap cap;
968 
969 		r = -EFAULT;
970 		if (copy_from_user(&cap, argp, sizeof(cap)))
971 			goto out;
972 		r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
973 		break;
974 	}
975 	default:
976 		r = -ENOIOCTLCMD;
977 	}
978 
979 out:
980 	return r;
981 }
982 
983 /* Get (and clear) the dirty memory log for a memory slot. */
984 int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log)
985 {
986 	struct kvm_memslots *slots;
987 	struct kvm_memory_slot *memslot;
988 	unsigned long ga, ga_end;
989 	int is_dirty = 0;
990 	int r;
991 	unsigned long n;
992 
993 	mutex_lock(&kvm->slots_lock);
994 
995 	r = kvm_get_dirty_log(kvm, log, &is_dirty);
996 	if (r)
997 		goto out;
998 
999 	/* If nothing is dirty, don't bother messing with page tables. */
1000 	if (is_dirty) {
1001 		slots = kvm_memslots(kvm);
1002 		memslot = id_to_memslot(slots, log->slot);
1003 
1004 		ga = memslot->base_gfn << PAGE_SHIFT;
1005 		ga_end = ga + (memslot->npages << PAGE_SHIFT);
1006 
1007 		kvm_info("%s: dirty, ga: %#lx, ga_end %#lx\n", __func__, ga,
1008 			 ga_end);
1009 
1010 		n = kvm_dirty_bitmap_bytes(memslot);
1011 		memset(memslot->dirty_bitmap, 0, n);
1012 	}
1013 
1014 	r = 0;
1015 out:
1016 	mutex_unlock(&kvm->slots_lock);
1017 	return r;
1018 
1019 }
1020 
1021 long kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
1022 {
1023 	long r;
1024 
1025 	switch (ioctl) {
1026 	default:
1027 		r = -ENOIOCTLCMD;
1028 	}
1029 
1030 	return r;
1031 }
1032 
1033 int kvm_arch_init(void *opaque)
1034 {
1035 	if (kvm_mips_callbacks) {
1036 		kvm_err("kvm: module already exists\n");
1037 		return -EEXIST;
1038 	}
1039 
1040 	return kvm_mips_emulation_init(&kvm_mips_callbacks);
1041 }
1042 
1043 void kvm_arch_exit(void)
1044 {
1045 	kvm_mips_callbacks = NULL;
1046 }
1047 
1048 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
1049 				  struct kvm_sregs *sregs)
1050 {
1051 	return -ENOIOCTLCMD;
1052 }
1053 
1054 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
1055 				  struct kvm_sregs *sregs)
1056 {
1057 	return -ENOIOCTLCMD;
1058 }
1059 
1060 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
1061 {
1062 }
1063 
1064 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1065 {
1066 	return -ENOIOCTLCMD;
1067 }
1068 
1069 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1070 {
1071 	return -ENOIOCTLCMD;
1072 }
1073 
1074 int kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
1075 {
1076 	return VM_FAULT_SIGBUS;
1077 }
1078 
1079 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
1080 {
1081 	int r;
1082 
1083 	switch (ext) {
1084 	case KVM_CAP_ONE_REG:
1085 	case KVM_CAP_ENABLE_CAP:
1086 		r = 1;
1087 		break;
1088 	case KVM_CAP_COALESCED_MMIO:
1089 		r = KVM_COALESCED_MMIO_PAGE_OFFSET;
1090 		break;
1091 	case KVM_CAP_MIPS_FPU:
1092 		/* We don't handle systems with inconsistent cpu_has_fpu */
1093 		r = !!raw_cpu_has_fpu;
1094 		break;
1095 	case KVM_CAP_MIPS_MSA:
1096 		/*
1097 		 * We don't support MSA vector partitioning yet:
1098 		 * 1) It would require explicit support which can't be tested
1099 		 *    yet due to lack of support in current hardware.
1100 		 * 2) It extends the state that would need to be saved/restored
1101 		 *    by e.g. QEMU for migration.
1102 		 *
1103 		 * When vector partitioning hardware becomes available, support
1104 		 * could be added by requiring a flag when enabling
1105 		 * KVM_CAP_MIPS_MSA capability to indicate that userland knows
1106 		 * to save/restore the appropriate extra state.
1107 		 */
1108 		r = cpu_has_msa && !(boot_cpu_data.msa_id & MSA_IR_WRPF);
1109 		break;
1110 	default:
1111 		r = 0;
1112 		break;
1113 	}
1114 	return r;
1115 }
1116 
1117 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
1118 {
1119 	return kvm_mips_pending_timer(vcpu);
1120 }
1121 
1122 int kvm_arch_vcpu_dump_regs(struct kvm_vcpu *vcpu)
1123 {
1124 	int i;
1125 	struct mips_coproc *cop0;
1126 
1127 	if (!vcpu)
1128 		return -1;
1129 
1130 	kvm_debug("VCPU Register Dump:\n");
1131 	kvm_debug("\tpc = 0x%08lx\n", vcpu->arch.pc);
1132 	kvm_debug("\texceptions: %08lx\n", vcpu->arch.pending_exceptions);
1133 
1134 	for (i = 0; i < 32; i += 4) {
1135 		kvm_debug("\tgpr%02d: %08lx %08lx %08lx %08lx\n", i,
1136 		       vcpu->arch.gprs[i],
1137 		       vcpu->arch.gprs[i + 1],
1138 		       vcpu->arch.gprs[i + 2], vcpu->arch.gprs[i + 3]);
1139 	}
1140 	kvm_debug("\thi: 0x%08lx\n", vcpu->arch.hi);
1141 	kvm_debug("\tlo: 0x%08lx\n", vcpu->arch.lo);
1142 
1143 	cop0 = vcpu->arch.cop0;
1144 	kvm_debug("\tStatus: 0x%08lx, Cause: 0x%08lx\n",
1145 		  kvm_read_c0_guest_status(cop0),
1146 		  kvm_read_c0_guest_cause(cop0));
1147 
1148 	kvm_debug("\tEPC: 0x%08lx\n", kvm_read_c0_guest_epc(cop0));
1149 
1150 	return 0;
1151 }
1152 
1153 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1154 {
1155 	int i;
1156 
1157 	for (i = 1; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1158 		vcpu->arch.gprs[i] = regs->gpr[i];
1159 	vcpu->arch.gprs[0] = 0; /* zero is special, and cannot be set. */
1160 	vcpu->arch.hi = regs->hi;
1161 	vcpu->arch.lo = regs->lo;
1162 	vcpu->arch.pc = regs->pc;
1163 
1164 	return 0;
1165 }
1166 
1167 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1168 {
1169 	int i;
1170 
1171 	for (i = 0; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1172 		regs->gpr[i] = vcpu->arch.gprs[i];
1173 
1174 	regs->hi = vcpu->arch.hi;
1175 	regs->lo = vcpu->arch.lo;
1176 	regs->pc = vcpu->arch.pc;
1177 
1178 	return 0;
1179 }
1180 
1181 static void kvm_mips_comparecount_func(unsigned long data)
1182 {
1183 	struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data;
1184 
1185 	kvm_mips_callbacks->queue_timer_int(vcpu);
1186 
1187 	vcpu->arch.wait = 0;
1188 	if (swait_active(&vcpu->wq))
1189 		swake_up(&vcpu->wq);
1190 }
1191 
1192 /* low level hrtimer wake routine */
1193 static enum hrtimer_restart kvm_mips_comparecount_wakeup(struct hrtimer *timer)
1194 {
1195 	struct kvm_vcpu *vcpu;
1196 
1197 	vcpu = container_of(timer, struct kvm_vcpu, arch.comparecount_timer);
1198 	kvm_mips_comparecount_func((unsigned long) vcpu);
1199 	return kvm_mips_count_timeout(vcpu);
1200 }
1201 
1202 int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
1203 {
1204 	kvm_mips_callbacks->vcpu_init(vcpu);
1205 	hrtimer_init(&vcpu->arch.comparecount_timer, CLOCK_MONOTONIC,
1206 		     HRTIMER_MODE_REL);
1207 	vcpu->arch.comparecount_timer.function = kvm_mips_comparecount_wakeup;
1208 	return 0;
1209 }
1210 
1211 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
1212 				  struct kvm_translation *tr)
1213 {
1214 	return 0;
1215 }
1216 
1217 /* Initial guest state */
1218 int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
1219 {
1220 	return kvm_mips_callbacks->vcpu_setup(vcpu);
1221 }
1222 
1223 static void kvm_mips_set_c0_status(void)
1224 {
1225 	uint32_t status = read_c0_status();
1226 
1227 	if (cpu_has_dsp)
1228 		status |= (ST0_MX);
1229 
1230 	write_c0_status(status);
1231 	ehb();
1232 }
1233 
1234 /*
1235  * Return value is in the form (errcode<<2 | RESUME_FLAG_HOST | RESUME_FLAG_NV)
1236  */
1237 int kvm_mips_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu)
1238 {
1239 	uint32_t cause = vcpu->arch.host_cp0_cause;
1240 	uint32_t exccode = (cause >> CAUSEB_EXCCODE) & 0x1f;
1241 	uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
1242 	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
1243 	enum emulation_result er = EMULATE_DONE;
1244 	int ret = RESUME_GUEST;
1245 
1246 	/* re-enable HTW before enabling interrupts */
1247 	htw_start();
1248 
1249 	/* Set a default exit reason */
1250 	run->exit_reason = KVM_EXIT_UNKNOWN;
1251 	run->ready_for_interrupt_injection = 1;
1252 
1253 	/*
1254 	 * Set the appropriate status bits based on host CPU features,
1255 	 * before we hit the scheduler
1256 	 */
1257 	kvm_mips_set_c0_status();
1258 
1259 	local_irq_enable();
1260 
1261 	kvm_debug("kvm_mips_handle_exit: cause: %#x, PC: %p, kvm_run: %p, kvm_vcpu: %p\n",
1262 			cause, opc, run, vcpu);
1263 
1264 	/*
1265 	 * Do a privilege check, if in UM most of these exit conditions end up
1266 	 * causing an exception to be delivered to the Guest Kernel
1267 	 */
1268 	er = kvm_mips_check_privilege(cause, opc, run, vcpu);
1269 	if (er == EMULATE_PRIV_FAIL) {
1270 		goto skip_emul;
1271 	} else if (er == EMULATE_FAIL) {
1272 		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1273 		ret = RESUME_HOST;
1274 		goto skip_emul;
1275 	}
1276 
1277 	switch (exccode) {
1278 	case EXCCODE_INT:
1279 		kvm_debug("[%d]EXCCODE_INT @ %p\n", vcpu->vcpu_id, opc);
1280 
1281 		++vcpu->stat.int_exits;
1282 		trace_kvm_exit(vcpu, INT_EXITS);
1283 
1284 		if (need_resched())
1285 			cond_resched();
1286 
1287 		ret = RESUME_GUEST;
1288 		break;
1289 
1290 	case EXCCODE_CPU:
1291 		kvm_debug("EXCCODE_CPU: @ PC: %p\n", opc);
1292 
1293 		++vcpu->stat.cop_unusable_exits;
1294 		trace_kvm_exit(vcpu, COP_UNUSABLE_EXITS);
1295 		ret = kvm_mips_callbacks->handle_cop_unusable(vcpu);
1296 		/* XXXKYMA: Might need to return to user space */
1297 		if (run->exit_reason == KVM_EXIT_IRQ_WINDOW_OPEN)
1298 			ret = RESUME_HOST;
1299 		break;
1300 
1301 	case EXCCODE_MOD:
1302 		++vcpu->stat.tlbmod_exits;
1303 		trace_kvm_exit(vcpu, TLBMOD_EXITS);
1304 		ret = kvm_mips_callbacks->handle_tlb_mod(vcpu);
1305 		break;
1306 
1307 	case EXCCODE_TLBS:
1308 		kvm_debug("TLB ST fault:  cause %#x, status %#lx, PC: %p, BadVaddr: %#lx\n",
1309 			  cause, kvm_read_c0_guest_status(vcpu->arch.cop0), opc,
1310 			  badvaddr);
1311 
1312 		++vcpu->stat.tlbmiss_st_exits;
1313 		trace_kvm_exit(vcpu, TLBMISS_ST_EXITS);
1314 		ret = kvm_mips_callbacks->handle_tlb_st_miss(vcpu);
1315 		break;
1316 
1317 	case EXCCODE_TLBL:
1318 		kvm_debug("TLB LD fault: cause %#x, PC: %p, BadVaddr: %#lx\n",
1319 			  cause, opc, badvaddr);
1320 
1321 		++vcpu->stat.tlbmiss_ld_exits;
1322 		trace_kvm_exit(vcpu, TLBMISS_LD_EXITS);
1323 		ret = kvm_mips_callbacks->handle_tlb_ld_miss(vcpu);
1324 		break;
1325 
1326 	case EXCCODE_ADES:
1327 		++vcpu->stat.addrerr_st_exits;
1328 		trace_kvm_exit(vcpu, ADDRERR_ST_EXITS);
1329 		ret = kvm_mips_callbacks->handle_addr_err_st(vcpu);
1330 		break;
1331 
1332 	case EXCCODE_ADEL:
1333 		++vcpu->stat.addrerr_ld_exits;
1334 		trace_kvm_exit(vcpu, ADDRERR_LD_EXITS);
1335 		ret = kvm_mips_callbacks->handle_addr_err_ld(vcpu);
1336 		break;
1337 
1338 	case EXCCODE_SYS:
1339 		++vcpu->stat.syscall_exits;
1340 		trace_kvm_exit(vcpu, SYSCALL_EXITS);
1341 		ret = kvm_mips_callbacks->handle_syscall(vcpu);
1342 		break;
1343 
1344 	case EXCCODE_RI:
1345 		++vcpu->stat.resvd_inst_exits;
1346 		trace_kvm_exit(vcpu, RESVD_INST_EXITS);
1347 		ret = kvm_mips_callbacks->handle_res_inst(vcpu);
1348 		break;
1349 
1350 	case EXCCODE_BP:
1351 		++vcpu->stat.break_inst_exits;
1352 		trace_kvm_exit(vcpu, BREAK_INST_EXITS);
1353 		ret = kvm_mips_callbacks->handle_break(vcpu);
1354 		break;
1355 
1356 	case EXCCODE_TR:
1357 		++vcpu->stat.trap_inst_exits;
1358 		trace_kvm_exit(vcpu, TRAP_INST_EXITS);
1359 		ret = kvm_mips_callbacks->handle_trap(vcpu);
1360 		break;
1361 
1362 	case EXCCODE_MSAFPE:
1363 		++vcpu->stat.msa_fpe_exits;
1364 		trace_kvm_exit(vcpu, MSA_FPE_EXITS);
1365 		ret = kvm_mips_callbacks->handle_msa_fpe(vcpu);
1366 		break;
1367 
1368 	case EXCCODE_FPE:
1369 		++vcpu->stat.fpe_exits;
1370 		trace_kvm_exit(vcpu, FPE_EXITS);
1371 		ret = kvm_mips_callbacks->handle_fpe(vcpu);
1372 		break;
1373 
1374 	case EXCCODE_MSADIS:
1375 		++vcpu->stat.msa_disabled_exits;
1376 		trace_kvm_exit(vcpu, MSA_DISABLED_EXITS);
1377 		ret = kvm_mips_callbacks->handle_msa_disabled(vcpu);
1378 		break;
1379 
1380 	default:
1381 		kvm_err("Exception Code: %d, not yet handled, @ PC: %p, inst: 0x%08x  BadVaddr: %#lx Status: %#lx\n",
1382 			exccode, opc, kvm_get_inst(opc, vcpu), badvaddr,
1383 			kvm_read_c0_guest_status(vcpu->arch.cop0));
1384 		kvm_arch_vcpu_dump_regs(vcpu);
1385 		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1386 		ret = RESUME_HOST;
1387 		break;
1388 
1389 	}
1390 
1391 skip_emul:
1392 	local_irq_disable();
1393 
1394 	if (er == EMULATE_DONE && !(ret & RESUME_HOST))
1395 		kvm_mips_deliver_interrupts(vcpu, cause);
1396 
1397 	if (!(ret & RESUME_HOST)) {
1398 		/* Only check for signals if not already exiting to userspace */
1399 		if (signal_pending(current)) {
1400 			run->exit_reason = KVM_EXIT_INTR;
1401 			ret = (-EINTR << 2) | RESUME_HOST;
1402 			++vcpu->stat.signal_exits;
1403 			trace_kvm_exit(vcpu, SIGNAL_EXITS);
1404 		}
1405 	}
1406 
1407 	if (ret == RESUME_GUEST) {
1408 		/*
1409 		 * If FPU / MSA are enabled (i.e. the guest's FPU / MSA context
1410 		 * is live), restore FCR31 / MSACSR.
1411 		 *
1412 		 * This should be before returning to the guest exception
1413 		 * vector, as it may well cause an [MSA] FP exception if there
1414 		 * are pending exception bits unmasked. (see
1415 		 * kvm_mips_csr_die_notifier() for how that is handled).
1416 		 */
1417 		if (kvm_mips_guest_has_fpu(&vcpu->arch) &&
1418 		    read_c0_status() & ST0_CU1)
1419 			__kvm_restore_fcsr(&vcpu->arch);
1420 
1421 		if (kvm_mips_guest_has_msa(&vcpu->arch) &&
1422 		    read_c0_config5() & MIPS_CONF5_MSAEN)
1423 			__kvm_restore_msacsr(&vcpu->arch);
1424 	}
1425 
1426 	/* Disable HTW before returning to guest or host */
1427 	htw_stop();
1428 
1429 	return ret;
1430 }
1431 
1432 /* Enable FPU for guest and restore context */
1433 void kvm_own_fpu(struct kvm_vcpu *vcpu)
1434 {
1435 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1436 	unsigned int sr, cfg5;
1437 
1438 	preempt_disable();
1439 
1440 	sr = kvm_read_c0_guest_status(cop0);
1441 
1442 	/*
1443 	 * If MSA state is already live, it is undefined how it interacts with
1444 	 * FR=0 FPU state, and we don't want to hit reserved instruction
1445 	 * exceptions trying to save the MSA state later when CU=1 && FR=1, so
1446 	 * play it safe and save it first.
1447 	 *
1448 	 * In theory we shouldn't ever hit this case since kvm_lose_fpu() should
1449 	 * get called when guest CU1 is set, however we can't trust the guest
1450 	 * not to clobber the status register directly via the commpage.
1451 	 */
1452 	if (cpu_has_msa && sr & ST0_CU1 && !(sr & ST0_FR) &&
1453 	    vcpu->arch.fpu_inuse & KVM_MIPS_FPU_MSA)
1454 		kvm_lose_fpu(vcpu);
1455 
1456 	/*
1457 	 * Enable FPU for guest
1458 	 * We set FR and FRE according to guest context
1459 	 */
1460 	change_c0_status(ST0_CU1 | ST0_FR, sr);
1461 	if (cpu_has_fre) {
1462 		cfg5 = kvm_read_c0_guest_config5(cop0);
1463 		change_c0_config5(MIPS_CONF5_FRE, cfg5);
1464 	}
1465 	enable_fpu_hazard();
1466 
1467 	/* If guest FPU state not active, restore it now */
1468 	if (!(vcpu->arch.fpu_inuse & KVM_MIPS_FPU_FPU)) {
1469 		__kvm_restore_fpu(&vcpu->arch);
1470 		vcpu->arch.fpu_inuse |= KVM_MIPS_FPU_FPU;
1471 	}
1472 
1473 	preempt_enable();
1474 }
1475 
1476 #ifdef CONFIG_CPU_HAS_MSA
1477 /* Enable MSA for guest and restore context */
1478 void kvm_own_msa(struct kvm_vcpu *vcpu)
1479 {
1480 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1481 	unsigned int sr, cfg5;
1482 
1483 	preempt_disable();
1484 
1485 	/*
1486 	 * Enable FPU if enabled in guest, since we're restoring FPU context
1487 	 * anyway. We set FR and FRE according to guest context.
1488 	 */
1489 	if (kvm_mips_guest_has_fpu(&vcpu->arch)) {
1490 		sr = kvm_read_c0_guest_status(cop0);
1491 
1492 		/*
1493 		 * If FR=0 FPU state is already live, it is undefined how it
1494 		 * interacts with MSA state, so play it safe and save it first.
1495 		 */
1496 		if (!(sr & ST0_FR) &&
1497 		    (vcpu->arch.fpu_inuse & (KVM_MIPS_FPU_FPU |
1498 				KVM_MIPS_FPU_MSA)) == KVM_MIPS_FPU_FPU)
1499 			kvm_lose_fpu(vcpu);
1500 
1501 		change_c0_status(ST0_CU1 | ST0_FR, sr);
1502 		if (sr & ST0_CU1 && cpu_has_fre) {
1503 			cfg5 = kvm_read_c0_guest_config5(cop0);
1504 			change_c0_config5(MIPS_CONF5_FRE, cfg5);
1505 		}
1506 	}
1507 
1508 	/* Enable MSA for guest */
1509 	set_c0_config5(MIPS_CONF5_MSAEN);
1510 	enable_fpu_hazard();
1511 
1512 	switch (vcpu->arch.fpu_inuse & (KVM_MIPS_FPU_FPU | KVM_MIPS_FPU_MSA)) {
1513 	case KVM_MIPS_FPU_FPU:
1514 		/*
1515 		 * Guest FPU state already loaded, only restore upper MSA state
1516 		 */
1517 		__kvm_restore_msa_upper(&vcpu->arch);
1518 		vcpu->arch.fpu_inuse |= KVM_MIPS_FPU_MSA;
1519 		break;
1520 	case 0:
1521 		/* Neither FPU or MSA already active, restore full MSA state */
1522 		__kvm_restore_msa(&vcpu->arch);
1523 		vcpu->arch.fpu_inuse |= KVM_MIPS_FPU_MSA;
1524 		if (kvm_mips_guest_has_fpu(&vcpu->arch))
1525 			vcpu->arch.fpu_inuse |= KVM_MIPS_FPU_FPU;
1526 		break;
1527 	default:
1528 		break;
1529 	}
1530 
1531 	preempt_enable();
1532 }
1533 #endif
1534 
1535 /* Drop FPU & MSA without saving it */
1536 void kvm_drop_fpu(struct kvm_vcpu *vcpu)
1537 {
1538 	preempt_disable();
1539 	if (cpu_has_msa && vcpu->arch.fpu_inuse & KVM_MIPS_FPU_MSA) {
1540 		disable_msa();
1541 		vcpu->arch.fpu_inuse &= ~KVM_MIPS_FPU_MSA;
1542 	}
1543 	if (vcpu->arch.fpu_inuse & KVM_MIPS_FPU_FPU) {
1544 		clear_c0_status(ST0_CU1 | ST0_FR);
1545 		vcpu->arch.fpu_inuse &= ~KVM_MIPS_FPU_FPU;
1546 	}
1547 	preempt_enable();
1548 }
1549 
1550 /* Save and disable FPU & MSA */
1551 void kvm_lose_fpu(struct kvm_vcpu *vcpu)
1552 {
1553 	/*
1554 	 * FPU & MSA get disabled in root context (hardware) when it is disabled
1555 	 * in guest context (software), but the register state in the hardware
1556 	 * may still be in use. This is why we explicitly re-enable the hardware
1557 	 * before saving.
1558 	 */
1559 
1560 	preempt_disable();
1561 	if (cpu_has_msa && vcpu->arch.fpu_inuse & KVM_MIPS_FPU_MSA) {
1562 		set_c0_config5(MIPS_CONF5_MSAEN);
1563 		enable_fpu_hazard();
1564 
1565 		__kvm_save_msa(&vcpu->arch);
1566 
1567 		/* Disable MSA & FPU */
1568 		disable_msa();
1569 		if (vcpu->arch.fpu_inuse & KVM_MIPS_FPU_FPU) {
1570 			clear_c0_status(ST0_CU1 | ST0_FR);
1571 			disable_fpu_hazard();
1572 		}
1573 		vcpu->arch.fpu_inuse &= ~(KVM_MIPS_FPU_FPU | KVM_MIPS_FPU_MSA);
1574 	} else if (vcpu->arch.fpu_inuse & KVM_MIPS_FPU_FPU) {
1575 		set_c0_status(ST0_CU1);
1576 		enable_fpu_hazard();
1577 
1578 		__kvm_save_fpu(&vcpu->arch);
1579 		vcpu->arch.fpu_inuse &= ~KVM_MIPS_FPU_FPU;
1580 
1581 		/* Disable FPU */
1582 		clear_c0_status(ST0_CU1 | ST0_FR);
1583 		disable_fpu_hazard();
1584 	}
1585 	preempt_enable();
1586 }
1587 
1588 /*
1589  * Step over a specific ctc1 to FCSR and a specific ctcmsa to MSACSR which are
1590  * used to restore guest FCSR/MSACSR state and may trigger a "harmless" FP/MSAFP
1591  * exception if cause bits are set in the value being written.
1592  */
1593 static int kvm_mips_csr_die_notify(struct notifier_block *self,
1594 				   unsigned long cmd, void *ptr)
1595 {
1596 	struct die_args *args = (struct die_args *)ptr;
1597 	struct pt_regs *regs = args->regs;
1598 	unsigned long pc;
1599 
1600 	/* Only interested in FPE and MSAFPE */
1601 	if (cmd != DIE_FP && cmd != DIE_MSAFP)
1602 		return NOTIFY_DONE;
1603 
1604 	/* Return immediately if guest context isn't active */
1605 	if (!(current->flags & PF_VCPU))
1606 		return NOTIFY_DONE;
1607 
1608 	/* Should never get here from user mode */
1609 	BUG_ON(user_mode(regs));
1610 
1611 	pc = instruction_pointer(regs);
1612 	switch (cmd) {
1613 	case DIE_FP:
1614 		/* match 2nd instruction in __kvm_restore_fcsr */
1615 		if (pc != (unsigned long)&__kvm_restore_fcsr + 4)
1616 			return NOTIFY_DONE;
1617 		break;
1618 	case DIE_MSAFP:
1619 		/* match 2nd/3rd instruction in __kvm_restore_msacsr */
1620 		if (!cpu_has_msa ||
1621 		    pc < (unsigned long)&__kvm_restore_msacsr + 4 ||
1622 		    pc > (unsigned long)&__kvm_restore_msacsr + 8)
1623 			return NOTIFY_DONE;
1624 		break;
1625 	}
1626 
1627 	/* Move PC forward a little and continue executing */
1628 	instruction_pointer(regs) += 4;
1629 
1630 	return NOTIFY_STOP;
1631 }
1632 
1633 static struct notifier_block kvm_mips_csr_die_notifier = {
1634 	.notifier_call = kvm_mips_csr_die_notify,
1635 };
1636 
1637 static int __init kvm_mips_init(void)
1638 {
1639 	int ret;
1640 
1641 	ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
1642 
1643 	if (ret)
1644 		return ret;
1645 
1646 	register_die_notifier(&kvm_mips_csr_die_notifier);
1647 
1648 	/*
1649 	 * On MIPS, kernel modules are executed from "mapped space", which
1650 	 * requires TLBs. The TLB handling code is statically linked with
1651 	 * the rest of the kernel (tlb.c) to avoid the possibility of
1652 	 * double faulting. The issue is that the TLB code references
1653 	 * routines that are part of the the KVM module, which are only
1654 	 * available once the module is loaded.
1655 	 */
1656 	kvm_mips_gfn_to_pfn = gfn_to_pfn;
1657 	kvm_mips_release_pfn_clean = kvm_release_pfn_clean;
1658 	kvm_mips_is_error_pfn = is_error_pfn;
1659 
1660 	return 0;
1661 }
1662 
1663 static void __exit kvm_mips_exit(void)
1664 {
1665 	kvm_exit();
1666 
1667 	kvm_mips_gfn_to_pfn = NULL;
1668 	kvm_mips_release_pfn_clean = NULL;
1669 	kvm_mips_is_error_pfn = NULL;
1670 
1671 	unregister_die_notifier(&kvm_mips_csr_die_notifier);
1672 }
1673 
1674 module_init(kvm_mips_init);
1675 module_exit(kvm_mips_exit);
1676 
1677 EXPORT_TRACEPOINT_SYMBOL(kvm_exit);
1678