xref: /openbmc/linux/arch/mips/kvm/mips.c (revision 8c749ce9)
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_wakeup",  VCPU_STAT(halt_wakeup),	 KVM_STAT_VCPU },
60 	{NULL}
61 };
62 
63 static int kvm_mips_reset_vcpu(struct kvm_vcpu *vcpu)
64 {
65 	int i;
66 
67 	for_each_possible_cpu(i) {
68 		vcpu->arch.guest_kernel_asid[i] = 0;
69 		vcpu->arch.guest_user_asid[i] = 0;
70 	}
71 
72 	return 0;
73 }
74 
75 /*
76  * XXXKYMA: We are simulatoring a processor that has the WII bit set in
77  * Config7, so we are "runnable" if interrupts are pending
78  */
79 int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
80 {
81 	return !!(vcpu->arch.pending_exceptions);
82 }
83 
84 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
85 {
86 	return 1;
87 }
88 
89 int kvm_arch_hardware_enable(void)
90 {
91 	return 0;
92 }
93 
94 int kvm_arch_hardware_setup(void)
95 {
96 	return 0;
97 }
98 
99 void kvm_arch_check_processor_compat(void *rtn)
100 {
101 	*(int *)rtn = 0;
102 }
103 
104 static void kvm_mips_init_tlbs(struct kvm *kvm)
105 {
106 	unsigned long wired;
107 
108 	/*
109 	 * Add a wired entry to the TLB, it is used to map the commpage to
110 	 * the Guest kernel
111 	 */
112 	wired = read_c0_wired();
113 	write_c0_wired(wired + 1);
114 	mtc0_tlbw_hazard();
115 	kvm->arch.commpage_tlb = wired;
116 
117 	kvm_debug("[%d] commpage TLB: %d\n", smp_processor_id(),
118 		  kvm->arch.commpage_tlb);
119 }
120 
121 static void kvm_mips_init_vm_percpu(void *arg)
122 {
123 	struct kvm *kvm = (struct kvm *)arg;
124 
125 	kvm_mips_init_tlbs(kvm);
126 	kvm_mips_callbacks->vm_init(kvm);
127 
128 }
129 
130 int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
131 {
132 	if (atomic_inc_return(&kvm_mips_instance) == 1) {
133 		kvm_debug("%s: 1st KVM instance, setup host TLB parameters\n",
134 			  __func__);
135 		on_each_cpu(kvm_mips_init_vm_percpu, kvm, 1);
136 	}
137 
138 	return 0;
139 }
140 
141 void kvm_mips_free_vcpus(struct kvm *kvm)
142 {
143 	unsigned int i;
144 	struct kvm_vcpu *vcpu;
145 
146 	/* Put the pages we reserved for the guest pmap */
147 	for (i = 0; i < kvm->arch.guest_pmap_npages; i++) {
148 		if (kvm->arch.guest_pmap[i] != KVM_INVALID_PAGE)
149 			kvm_mips_release_pfn_clean(kvm->arch.guest_pmap[i]);
150 	}
151 	kfree(kvm->arch.guest_pmap);
152 
153 	kvm_for_each_vcpu(i, vcpu, kvm) {
154 		kvm_arch_vcpu_free(vcpu);
155 	}
156 
157 	mutex_lock(&kvm->lock);
158 
159 	for (i = 0; i < atomic_read(&kvm->online_vcpus); i++)
160 		kvm->vcpus[i] = NULL;
161 
162 	atomic_set(&kvm->online_vcpus, 0);
163 
164 	mutex_unlock(&kvm->lock);
165 }
166 
167 static void kvm_mips_uninit_tlbs(void *arg)
168 {
169 	/* Restore wired count */
170 	write_c0_wired(0);
171 	mtc0_tlbw_hazard();
172 	/* Clear out all the TLBs */
173 	kvm_local_flush_tlb_all();
174 }
175 
176 void kvm_arch_destroy_vm(struct kvm *kvm)
177 {
178 	kvm_mips_free_vcpus(kvm);
179 
180 	/* If this is the last instance, restore wired count */
181 	if (atomic_dec_return(&kvm_mips_instance) == 0) {
182 		kvm_debug("%s: last KVM instance, restoring TLB parameters\n",
183 			  __func__);
184 		on_each_cpu(kvm_mips_uninit_tlbs, NULL, 1);
185 	}
186 }
187 
188 long kvm_arch_dev_ioctl(struct file *filp, unsigned int ioctl,
189 			unsigned long arg)
190 {
191 	return -ENOIOCTLCMD;
192 }
193 
194 int kvm_arch_create_memslot(struct kvm *kvm, struct kvm_memory_slot *slot,
195 			    unsigned long npages)
196 {
197 	return 0;
198 }
199 
200 int kvm_arch_prepare_memory_region(struct kvm *kvm,
201 				   struct kvm_memory_slot *memslot,
202 				   const struct kvm_userspace_memory_region *mem,
203 				   enum kvm_mr_change change)
204 {
205 	return 0;
206 }
207 
208 void kvm_arch_commit_memory_region(struct kvm *kvm,
209 				   const struct kvm_userspace_memory_region *mem,
210 				   const struct kvm_memory_slot *old,
211 				   const struct kvm_memory_slot *new,
212 				   enum kvm_mr_change change)
213 {
214 	unsigned long npages = 0;
215 	int i;
216 
217 	kvm_debug("%s: kvm: %p slot: %d, GPA: %llx, size: %llx, QVA: %llx\n",
218 		  __func__, kvm, mem->slot, mem->guest_phys_addr,
219 		  mem->memory_size, mem->userspace_addr);
220 
221 	/* Setup Guest PMAP table */
222 	if (!kvm->arch.guest_pmap) {
223 		if (mem->slot == 0)
224 			npages = mem->memory_size >> PAGE_SHIFT;
225 
226 		if (npages) {
227 			kvm->arch.guest_pmap_npages = npages;
228 			kvm->arch.guest_pmap =
229 			    kzalloc(npages * sizeof(unsigned long), GFP_KERNEL);
230 
231 			if (!kvm->arch.guest_pmap) {
232 				kvm_err("Failed to allocate guest PMAP\n");
233 				return;
234 			}
235 
236 			kvm_debug("Allocated space for Guest PMAP Table (%ld pages) @ %p\n",
237 				  npages, kvm->arch.guest_pmap);
238 
239 			/* Now setup the page table */
240 			for (i = 0; i < npages; i++)
241 				kvm->arch.guest_pmap[i] = KVM_INVALID_PAGE;
242 		}
243 	}
244 }
245 
246 struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
247 {
248 	int err, size, offset;
249 	void *gebase;
250 	int i;
251 
252 	struct kvm_vcpu *vcpu = kzalloc(sizeof(struct kvm_vcpu), GFP_KERNEL);
253 
254 	if (!vcpu) {
255 		err = -ENOMEM;
256 		goto out;
257 	}
258 
259 	err = kvm_vcpu_init(vcpu, kvm, id);
260 
261 	if (err)
262 		goto out_free_cpu;
263 
264 	kvm_debug("kvm @ %p: create cpu %d at %p\n", kvm, id, vcpu);
265 
266 	/*
267 	 * Allocate space for host mode exception handlers that handle
268 	 * guest mode exits
269 	 */
270 	if (cpu_has_veic || cpu_has_vint)
271 		size = 0x200 + VECTORSPACING * 64;
272 	else
273 		size = 0x4000;
274 
275 	/* Save Linux EBASE */
276 	vcpu->arch.host_ebase = (void *)read_c0_ebase();
277 
278 	gebase = kzalloc(ALIGN(size, PAGE_SIZE), GFP_KERNEL);
279 
280 	if (!gebase) {
281 		err = -ENOMEM;
282 		goto out_uninit_cpu;
283 	}
284 	kvm_debug("Allocated %d bytes for KVM Exception Handlers @ %p\n",
285 		  ALIGN(size, PAGE_SIZE), gebase);
286 
287 	/* Save new ebase */
288 	vcpu->arch.guest_ebase = gebase;
289 
290 	/* Copy L1 Guest Exception handler to correct offset */
291 
292 	/* TLB Refill, EXL = 0 */
293 	memcpy(gebase, mips32_exception,
294 	       mips32_exceptionEnd - mips32_exception);
295 
296 	/* General Exception Entry point */
297 	memcpy(gebase + 0x180, mips32_exception,
298 	       mips32_exceptionEnd - mips32_exception);
299 
300 	/* For vectored interrupts poke the exception code @ all offsets 0-7 */
301 	for (i = 0; i < 8; i++) {
302 		kvm_debug("L1 Vectored handler @ %p\n",
303 			  gebase + 0x200 + (i * VECTORSPACING));
304 		memcpy(gebase + 0x200 + (i * VECTORSPACING), mips32_exception,
305 		       mips32_exceptionEnd - mips32_exception);
306 	}
307 
308 	/* General handler, relocate to unmapped space for sanity's sake */
309 	offset = 0x2000;
310 	kvm_debug("Installing KVM Exception handlers @ %p, %#x bytes\n",
311 		  gebase + offset,
312 		  mips32_GuestExceptionEnd - mips32_GuestException);
313 
314 	memcpy(gebase + offset, mips32_GuestException,
315 	       mips32_GuestExceptionEnd - mips32_GuestException);
316 
317 	/* Invalidate the icache for these ranges */
318 	local_flush_icache_range((unsigned long)gebase,
319 				(unsigned long)gebase + ALIGN(size, PAGE_SIZE));
320 
321 	/*
322 	 * Allocate comm page for guest kernel, a TLB will be reserved for
323 	 * mapping GVA @ 0xFFFF8000 to this page
324 	 */
325 	vcpu->arch.kseg0_commpage = kzalloc(PAGE_SIZE << 1, GFP_KERNEL);
326 
327 	if (!vcpu->arch.kseg0_commpage) {
328 		err = -ENOMEM;
329 		goto out_free_gebase;
330 	}
331 
332 	kvm_debug("Allocated COMM page @ %p\n", vcpu->arch.kseg0_commpage);
333 	kvm_mips_commpage_init(vcpu);
334 
335 	/* Init */
336 	vcpu->arch.last_sched_cpu = -1;
337 
338 	/* Start off the timer */
339 	kvm_mips_init_count(vcpu);
340 
341 	return vcpu;
342 
343 out_free_gebase:
344 	kfree(gebase);
345 
346 out_uninit_cpu:
347 	kvm_vcpu_uninit(vcpu);
348 
349 out_free_cpu:
350 	kfree(vcpu);
351 
352 out:
353 	return ERR_PTR(err);
354 }
355 
356 void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
357 {
358 	hrtimer_cancel(&vcpu->arch.comparecount_timer);
359 
360 	kvm_vcpu_uninit(vcpu);
361 
362 	kvm_mips_dump_stats(vcpu);
363 
364 	kfree(vcpu->arch.guest_ebase);
365 	kfree(vcpu->arch.kseg0_commpage);
366 	kfree(vcpu);
367 }
368 
369 void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
370 {
371 	kvm_arch_vcpu_free(vcpu);
372 }
373 
374 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
375 					struct kvm_guest_debug *dbg)
376 {
377 	return -ENOIOCTLCMD;
378 }
379 
380 int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
381 {
382 	int r = 0;
383 	sigset_t sigsaved;
384 
385 	if (vcpu->sigset_active)
386 		sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);
387 
388 	if (vcpu->mmio_needed) {
389 		if (!vcpu->mmio_is_write)
390 			kvm_mips_complete_mmio_load(vcpu, run);
391 		vcpu->mmio_needed = 0;
392 	}
393 
394 	lose_fpu(1);
395 
396 	local_irq_disable();
397 	/* Check if we have any exceptions/interrupts pending */
398 	kvm_mips_deliver_interrupts(vcpu,
399 				    kvm_read_c0_guest_cause(vcpu->arch.cop0));
400 
401 	__kvm_guest_enter();
402 
403 	/* Disable hardware page table walking while in guest */
404 	htw_stop();
405 
406 	r = __kvm_mips_vcpu_run(run, vcpu);
407 
408 	/* Re-enable HTW before enabling interrupts */
409 	htw_start();
410 
411 	__kvm_guest_exit();
412 	local_irq_enable();
413 
414 	if (vcpu->sigset_active)
415 		sigprocmask(SIG_SETMASK, &sigsaved, NULL);
416 
417 	return r;
418 }
419 
420 int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
421 			     struct kvm_mips_interrupt *irq)
422 {
423 	int intr = (int)irq->irq;
424 	struct kvm_vcpu *dvcpu = NULL;
425 
426 	if (intr == 3 || intr == -3 || intr == 4 || intr == -4)
427 		kvm_debug("%s: CPU: %d, INTR: %d\n", __func__, irq->cpu,
428 			  (int)intr);
429 
430 	if (irq->cpu == -1)
431 		dvcpu = vcpu;
432 	else
433 		dvcpu = vcpu->kvm->vcpus[irq->cpu];
434 
435 	if (intr == 2 || intr == 3 || intr == 4) {
436 		kvm_mips_callbacks->queue_io_int(dvcpu, irq);
437 
438 	} else if (intr == -2 || intr == -3 || intr == -4) {
439 		kvm_mips_callbacks->dequeue_io_int(dvcpu, irq);
440 	} else {
441 		kvm_err("%s: invalid interrupt ioctl (%d:%d)\n", __func__,
442 			irq->cpu, irq->irq);
443 		return -EINVAL;
444 	}
445 
446 	dvcpu->arch.wait = 0;
447 
448 	if (waitqueue_active(&dvcpu->wq))
449 		wake_up_interruptible(&dvcpu->wq);
450 
451 	return 0;
452 }
453 
454 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
455 				    struct kvm_mp_state *mp_state)
456 {
457 	return -ENOIOCTLCMD;
458 }
459 
460 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
461 				    struct kvm_mp_state *mp_state)
462 {
463 	return -ENOIOCTLCMD;
464 }
465 
466 static u64 kvm_mips_get_one_regs[] = {
467 	KVM_REG_MIPS_R0,
468 	KVM_REG_MIPS_R1,
469 	KVM_REG_MIPS_R2,
470 	KVM_REG_MIPS_R3,
471 	KVM_REG_MIPS_R4,
472 	KVM_REG_MIPS_R5,
473 	KVM_REG_MIPS_R6,
474 	KVM_REG_MIPS_R7,
475 	KVM_REG_MIPS_R8,
476 	KVM_REG_MIPS_R9,
477 	KVM_REG_MIPS_R10,
478 	KVM_REG_MIPS_R11,
479 	KVM_REG_MIPS_R12,
480 	KVM_REG_MIPS_R13,
481 	KVM_REG_MIPS_R14,
482 	KVM_REG_MIPS_R15,
483 	KVM_REG_MIPS_R16,
484 	KVM_REG_MIPS_R17,
485 	KVM_REG_MIPS_R18,
486 	KVM_REG_MIPS_R19,
487 	KVM_REG_MIPS_R20,
488 	KVM_REG_MIPS_R21,
489 	KVM_REG_MIPS_R22,
490 	KVM_REG_MIPS_R23,
491 	KVM_REG_MIPS_R24,
492 	KVM_REG_MIPS_R25,
493 	KVM_REG_MIPS_R26,
494 	KVM_REG_MIPS_R27,
495 	KVM_REG_MIPS_R28,
496 	KVM_REG_MIPS_R29,
497 	KVM_REG_MIPS_R30,
498 	KVM_REG_MIPS_R31,
499 
500 	KVM_REG_MIPS_HI,
501 	KVM_REG_MIPS_LO,
502 	KVM_REG_MIPS_PC,
503 
504 	KVM_REG_MIPS_CP0_INDEX,
505 	KVM_REG_MIPS_CP0_CONTEXT,
506 	KVM_REG_MIPS_CP0_USERLOCAL,
507 	KVM_REG_MIPS_CP0_PAGEMASK,
508 	KVM_REG_MIPS_CP0_WIRED,
509 	KVM_REG_MIPS_CP0_HWRENA,
510 	KVM_REG_MIPS_CP0_BADVADDR,
511 	KVM_REG_MIPS_CP0_COUNT,
512 	KVM_REG_MIPS_CP0_ENTRYHI,
513 	KVM_REG_MIPS_CP0_COMPARE,
514 	KVM_REG_MIPS_CP0_STATUS,
515 	KVM_REG_MIPS_CP0_CAUSE,
516 	KVM_REG_MIPS_CP0_EPC,
517 	KVM_REG_MIPS_CP0_PRID,
518 	KVM_REG_MIPS_CP0_CONFIG,
519 	KVM_REG_MIPS_CP0_CONFIG1,
520 	KVM_REG_MIPS_CP0_CONFIG2,
521 	KVM_REG_MIPS_CP0_CONFIG3,
522 	KVM_REG_MIPS_CP0_CONFIG4,
523 	KVM_REG_MIPS_CP0_CONFIG5,
524 	KVM_REG_MIPS_CP0_CONFIG7,
525 	KVM_REG_MIPS_CP0_ERROREPC,
526 
527 	KVM_REG_MIPS_COUNT_CTL,
528 	KVM_REG_MIPS_COUNT_RESUME,
529 	KVM_REG_MIPS_COUNT_HZ,
530 };
531 
532 static int kvm_mips_get_reg(struct kvm_vcpu *vcpu,
533 			    const struct kvm_one_reg *reg)
534 {
535 	struct mips_coproc *cop0 = vcpu->arch.cop0;
536 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
537 	int ret;
538 	s64 v;
539 	s64 vs[2];
540 	unsigned int idx;
541 
542 	switch (reg->id) {
543 	/* General purpose registers */
544 	case KVM_REG_MIPS_R0 ... KVM_REG_MIPS_R31:
545 		v = (long)vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0];
546 		break;
547 	case KVM_REG_MIPS_HI:
548 		v = (long)vcpu->arch.hi;
549 		break;
550 	case KVM_REG_MIPS_LO:
551 		v = (long)vcpu->arch.lo;
552 		break;
553 	case KVM_REG_MIPS_PC:
554 		v = (long)vcpu->arch.pc;
555 		break;
556 
557 	/* Floating point registers */
558 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
559 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
560 			return -EINVAL;
561 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
562 		/* Odd singles in top of even double when FR=0 */
563 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
564 			v = get_fpr32(&fpu->fpr[idx], 0);
565 		else
566 			v = get_fpr32(&fpu->fpr[idx & ~1], idx & 1);
567 		break;
568 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
569 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
570 			return -EINVAL;
571 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
572 		/* Can't access odd doubles in FR=0 mode */
573 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
574 			return -EINVAL;
575 		v = get_fpr64(&fpu->fpr[idx], 0);
576 		break;
577 	case KVM_REG_MIPS_FCR_IR:
578 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
579 			return -EINVAL;
580 		v = boot_cpu_data.fpu_id;
581 		break;
582 	case KVM_REG_MIPS_FCR_CSR:
583 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
584 			return -EINVAL;
585 		v = fpu->fcr31;
586 		break;
587 
588 	/* MIPS SIMD Architecture (MSA) registers */
589 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
590 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
591 			return -EINVAL;
592 		/* Can't access MSA registers in FR=0 mode */
593 		if (!(kvm_read_c0_guest_status(cop0) & ST0_FR))
594 			return -EINVAL;
595 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
596 #ifdef CONFIG_CPU_LITTLE_ENDIAN
597 		/* least significant byte first */
598 		vs[0] = get_fpr64(&fpu->fpr[idx], 0);
599 		vs[1] = get_fpr64(&fpu->fpr[idx], 1);
600 #else
601 		/* most significant byte first */
602 		vs[0] = get_fpr64(&fpu->fpr[idx], 1);
603 		vs[1] = get_fpr64(&fpu->fpr[idx], 0);
604 #endif
605 		break;
606 	case KVM_REG_MIPS_MSA_IR:
607 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
608 			return -EINVAL;
609 		v = boot_cpu_data.msa_id;
610 		break;
611 	case KVM_REG_MIPS_MSA_CSR:
612 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
613 			return -EINVAL;
614 		v = fpu->msacsr;
615 		break;
616 
617 	/* Co-processor 0 registers */
618 	case KVM_REG_MIPS_CP0_INDEX:
619 		v = (long)kvm_read_c0_guest_index(cop0);
620 		break;
621 	case KVM_REG_MIPS_CP0_CONTEXT:
622 		v = (long)kvm_read_c0_guest_context(cop0);
623 		break;
624 	case KVM_REG_MIPS_CP0_USERLOCAL:
625 		v = (long)kvm_read_c0_guest_userlocal(cop0);
626 		break;
627 	case KVM_REG_MIPS_CP0_PAGEMASK:
628 		v = (long)kvm_read_c0_guest_pagemask(cop0);
629 		break;
630 	case KVM_REG_MIPS_CP0_WIRED:
631 		v = (long)kvm_read_c0_guest_wired(cop0);
632 		break;
633 	case KVM_REG_MIPS_CP0_HWRENA:
634 		v = (long)kvm_read_c0_guest_hwrena(cop0);
635 		break;
636 	case KVM_REG_MIPS_CP0_BADVADDR:
637 		v = (long)kvm_read_c0_guest_badvaddr(cop0);
638 		break;
639 	case KVM_REG_MIPS_CP0_ENTRYHI:
640 		v = (long)kvm_read_c0_guest_entryhi(cop0);
641 		break;
642 	case KVM_REG_MIPS_CP0_COMPARE:
643 		v = (long)kvm_read_c0_guest_compare(cop0);
644 		break;
645 	case KVM_REG_MIPS_CP0_STATUS:
646 		v = (long)kvm_read_c0_guest_status(cop0);
647 		break;
648 	case KVM_REG_MIPS_CP0_CAUSE:
649 		v = (long)kvm_read_c0_guest_cause(cop0);
650 		break;
651 	case KVM_REG_MIPS_CP0_EPC:
652 		v = (long)kvm_read_c0_guest_epc(cop0);
653 		break;
654 	case KVM_REG_MIPS_CP0_PRID:
655 		v = (long)kvm_read_c0_guest_prid(cop0);
656 		break;
657 	case KVM_REG_MIPS_CP0_CONFIG:
658 		v = (long)kvm_read_c0_guest_config(cop0);
659 		break;
660 	case KVM_REG_MIPS_CP0_CONFIG1:
661 		v = (long)kvm_read_c0_guest_config1(cop0);
662 		break;
663 	case KVM_REG_MIPS_CP0_CONFIG2:
664 		v = (long)kvm_read_c0_guest_config2(cop0);
665 		break;
666 	case KVM_REG_MIPS_CP0_CONFIG3:
667 		v = (long)kvm_read_c0_guest_config3(cop0);
668 		break;
669 	case KVM_REG_MIPS_CP0_CONFIG4:
670 		v = (long)kvm_read_c0_guest_config4(cop0);
671 		break;
672 	case KVM_REG_MIPS_CP0_CONFIG5:
673 		v = (long)kvm_read_c0_guest_config5(cop0);
674 		break;
675 	case KVM_REG_MIPS_CP0_CONFIG7:
676 		v = (long)kvm_read_c0_guest_config7(cop0);
677 		break;
678 	case KVM_REG_MIPS_CP0_ERROREPC:
679 		v = (long)kvm_read_c0_guest_errorepc(cop0);
680 		break;
681 	/* registers to be handled specially */
682 	case KVM_REG_MIPS_CP0_COUNT:
683 	case KVM_REG_MIPS_COUNT_CTL:
684 	case KVM_REG_MIPS_COUNT_RESUME:
685 	case KVM_REG_MIPS_COUNT_HZ:
686 		ret = kvm_mips_callbacks->get_one_reg(vcpu, reg, &v);
687 		if (ret)
688 			return ret;
689 		break;
690 	default:
691 		return -EINVAL;
692 	}
693 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
694 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
695 
696 		return put_user(v, uaddr64);
697 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
698 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
699 		u32 v32 = (u32)v;
700 
701 		return put_user(v32, uaddr32);
702 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
703 		void __user *uaddr = (void __user *)(long)reg->addr;
704 
705 		return copy_to_user(uaddr, vs, 16);
706 	} else {
707 		return -EINVAL;
708 	}
709 }
710 
711 static int kvm_mips_set_reg(struct kvm_vcpu *vcpu,
712 			    const struct kvm_one_reg *reg)
713 {
714 	struct mips_coproc *cop0 = vcpu->arch.cop0;
715 	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
716 	s64 v;
717 	s64 vs[2];
718 	unsigned int idx;
719 
720 	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
721 		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
722 
723 		if (get_user(v, uaddr64) != 0)
724 			return -EFAULT;
725 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
726 		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
727 		s32 v32;
728 
729 		if (get_user(v32, uaddr32) != 0)
730 			return -EFAULT;
731 		v = (s64)v32;
732 	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
733 		void __user *uaddr = (void __user *)(long)reg->addr;
734 
735 		return copy_from_user(vs, uaddr, 16);
736 	} else {
737 		return -EINVAL;
738 	}
739 
740 	switch (reg->id) {
741 	/* General purpose registers */
742 	case KVM_REG_MIPS_R0:
743 		/* Silently ignore requests to set $0 */
744 		break;
745 	case KVM_REG_MIPS_R1 ... KVM_REG_MIPS_R31:
746 		vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0] = v;
747 		break;
748 	case KVM_REG_MIPS_HI:
749 		vcpu->arch.hi = v;
750 		break;
751 	case KVM_REG_MIPS_LO:
752 		vcpu->arch.lo = v;
753 		break;
754 	case KVM_REG_MIPS_PC:
755 		vcpu->arch.pc = v;
756 		break;
757 
758 	/* Floating point registers */
759 	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
760 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
761 			return -EINVAL;
762 		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
763 		/* Odd singles in top of even double when FR=0 */
764 		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
765 			set_fpr32(&fpu->fpr[idx], 0, v);
766 		else
767 			set_fpr32(&fpu->fpr[idx & ~1], idx & 1, v);
768 		break;
769 	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
770 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
771 			return -EINVAL;
772 		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
773 		/* Can't access odd doubles in FR=0 mode */
774 		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
775 			return -EINVAL;
776 		set_fpr64(&fpu->fpr[idx], 0, v);
777 		break;
778 	case KVM_REG_MIPS_FCR_IR:
779 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
780 			return -EINVAL;
781 		/* Read-only */
782 		break;
783 	case KVM_REG_MIPS_FCR_CSR:
784 		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
785 			return -EINVAL;
786 		fpu->fcr31 = v;
787 		break;
788 
789 	/* MIPS SIMD Architecture (MSA) registers */
790 	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
791 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
792 			return -EINVAL;
793 		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
794 #ifdef CONFIG_CPU_LITTLE_ENDIAN
795 		/* least significant byte first */
796 		set_fpr64(&fpu->fpr[idx], 0, vs[0]);
797 		set_fpr64(&fpu->fpr[idx], 1, vs[1]);
798 #else
799 		/* most significant byte first */
800 		set_fpr64(&fpu->fpr[idx], 1, vs[0]);
801 		set_fpr64(&fpu->fpr[idx], 0, vs[1]);
802 #endif
803 		break;
804 	case KVM_REG_MIPS_MSA_IR:
805 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
806 			return -EINVAL;
807 		/* Read-only */
808 		break;
809 	case KVM_REG_MIPS_MSA_CSR:
810 		if (!kvm_mips_guest_has_msa(&vcpu->arch))
811 			return -EINVAL;
812 		fpu->msacsr = v;
813 		break;
814 
815 	/* Co-processor 0 registers */
816 	case KVM_REG_MIPS_CP0_INDEX:
817 		kvm_write_c0_guest_index(cop0, v);
818 		break;
819 	case KVM_REG_MIPS_CP0_CONTEXT:
820 		kvm_write_c0_guest_context(cop0, v);
821 		break;
822 	case KVM_REG_MIPS_CP0_USERLOCAL:
823 		kvm_write_c0_guest_userlocal(cop0, v);
824 		break;
825 	case KVM_REG_MIPS_CP0_PAGEMASK:
826 		kvm_write_c0_guest_pagemask(cop0, v);
827 		break;
828 	case KVM_REG_MIPS_CP0_WIRED:
829 		kvm_write_c0_guest_wired(cop0, v);
830 		break;
831 	case KVM_REG_MIPS_CP0_HWRENA:
832 		kvm_write_c0_guest_hwrena(cop0, v);
833 		break;
834 	case KVM_REG_MIPS_CP0_BADVADDR:
835 		kvm_write_c0_guest_badvaddr(cop0, v);
836 		break;
837 	case KVM_REG_MIPS_CP0_ENTRYHI:
838 		kvm_write_c0_guest_entryhi(cop0, v);
839 		break;
840 	case KVM_REG_MIPS_CP0_STATUS:
841 		kvm_write_c0_guest_status(cop0, v);
842 		break;
843 	case KVM_REG_MIPS_CP0_EPC:
844 		kvm_write_c0_guest_epc(cop0, v);
845 		break;
846 	case KVM_REG_MIPS_CP0_PRID:
847 		kvm_write_c0_guest_prid(cop0, v);
848 		break;
849 	case KVM_REG_MIPS_CP0_ERROREPC:
850 		kvm_write_c0_guest_errorepc(cop0, v);
851 		break;
852 	/* registers to be handled specially */
853 	case KVM_REG_MIPS_CP0_COUNT:
854 	case KVM_REG_MIPS_CP0_COMPARE:
855 	case KVM_REG_MIPS_CP0_CAUSE:
856 	case KVM_REG_MIPS_CP0_CONFIG:
857 	case KVM_REG_MIPS_CP0_CONFIG1:
858 	case KVM_REG_MIPS_CP0_CONFIG2:
859 	case KVM_REG_MIPS_CP0_CONFIG3:
860 	case KVM_REG_MIPS_CP0_CONFIG4:
861 	case KVM_REG_MIPS_CP0_CONFIG5:
862 	case KVM_REG_MIPS_COUNT_CTL:
863 	case KVM_REG_MIPS_COUNT_RESUME:
864 	case KVM_REG_MIPS_COUNT_HZ:
865 		return kvm_mips_callbacks->set_one_reg(vcpu, reg, v);
866 	default:
867 		return -EINVAL;
868 	}
869 	return 0;
870 }
871 
872 static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
873 				     struct kvm_enable_cap *cap)
874 {
875 	int r = 0;
876 
877 	if (!kvm_vm_ioctl_check_extension(vcpu->kvm, cap->cap))
878 		return -EINVAL;
879 	if (cap->flags)
880 		return -EINVAL;
881 	if (cap->args[0])
882 		return -EINVAL;
883 
884 	switch (cap->cap) {
885 	case KVM_CAP_MIPS_FPU:
886 		vcpu->arch.fpu_enabled = true;
887 		break;
888 	case KVM_CAP_MIPS_MSA:
889 		vcpu->arch.msa_enabled = true;
890 		break;
891 	default:
892 		r = -EINVAL;
893 		break;
894 	}
895 
896 	return r;
897 }
898 
899 long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl,
900 			 unsigned long arg)
901 {
902 	struct kvm_vcpu *vcpu = filp->private_data;
903 	void __user *argp = (void __user *)arg;
904 	long r;
905 
906 	switch (ioctl) {
907 	case KVM_SET_ONE_REG:
908 	case KVM_GET_ONE_REG: {
909 		struct kvm_one_reg reg;
910 
911 		if (copy_from_user(&reg, argp, sizeof(reg)))
912 			return -EFAULT;
913 		if (ioctl == KVM_SET_ONE_REG)
914 			return kvm_mips_set_reg(vcpu, &reg);
915 		else
916 			return kvm_mips_get_reg(vcpu, &reg);
917 	}
918 	case KVM_GET_REG_LIST: {
919 		struct kvm_reg_list __user *user_list = argp;
920 		u64 __user *reg_dest;
921 		struct kvm_reg_list reg_list;
922 		unsigned n;
923 
924 		if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
925 			return -EFAULT;
926 		n = reg_list.n;
927 		reg_list.n = ARRAY_SIZE(kvm_mips_get_one_regs);
928 		if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
929 			return -EFAULT;
930 		if (n < reg_list.n)
931 			return -E2BIG;
932 		reg_dest = user_list->reg;
933 		if (copy_to_user(reg_dest, kvm_mips_get_one_regs,
934 				 sizeof(kvm_mips_get_one_regs)))
935 			return -EFAULT;
936 		return 0;
937 	}
938 	case KVM_NMI:
939 		/* Treat the NMI as a CPU reset */
940 		r = kvm_mips_reset_vcpu(vcpu);
941 		break;
942 	case KVM_INTERRUPT:
943 		{
944 			struct kvm_mips_interrupt irq;
945 
946 			r = -EFAULT;
947 			if (copy_from_user(&irq, argp, sizeof(irq)))
948 				goto out;
949 
950 			kvm_debug("[%d] %s: irq: %d\n", vcpu->vcpu_id, __func__,
951 				  irq.irq);
952 
953 			r = kvm_vcpu_ioctl_interrupt(vcpu, &irq);
954 			break;
955 		}
956 	case KVM_ENABLE_CAP: {
957 		struct kvm_enable_cap cap;
958 
959 		r = -EFAULT;
960 		if (copy_from_user(&cap, argp, sizeof(cap)))
961 			goto out;
962 		r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
963 		break;
964 	}
965 	default:
966 		r = -ENOIOCTLCMD;
967 	}
968 
969 out:
970 	return r;
971 }
972 
973 /* Get (and clear) the dirty memory log for a memory slot. */
974 int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log)
975 {
976 	struct kvm_memslots *slots;
977 	struct kvm_memory_slot *memslot;
978 	unsigned long ga, ga_end;
979 	int is_dirty = 0;
980 	int r;
981 	unsigned long n;
982 
983 	mutex_lock(&kvm->slots_lock);
984 
985 	r = kvm_get_dirty_log(kvm, log, &is_dirty);
986 	if (r)
987 		goto out;
988 
989 	/* If nothing is dirty, don't bother messing with page tables. */
990 	if (is_dirty) {
991 		slots = kvm_memslots(kvm);
992 		memslot = id_to_memslot(slots, log->slot);
993 
994 		ga = memslot->base_gfn << PAGE_SHIFT;
995 		ga_end = ga + (memslot->npages << PAGE_SHIFT);
996 
997 		kvm_info("%s: dirty, ga: %#lx, ga_end %#lx\n", __func__, ga,
998 			 ga_end);
999 
1000 		n = kvm_dirty_bitmap_bytes(memslot);
1001 		memset(memslot->dirty_bitmap, 0, n);
1002 	}
1003 
1004 	r = 0;
1005 out:
1006 	mutex_unlock(&kvm->slots_lock);
1007 	return r;
1008 
1009 }
1010 
1011 long kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
1012 {
1013 	long r;
1014 
1015 	switch (ioctl) {
1016 	default:
1017 		r = -ENOIOCTLCMD;
1018 	}
1019 
1020 	return r;
1021 }
1022 
1023 int kvm_arch_init(void *opaque)
1024 {
1025 	if (kvm_mips_callbacks) {
1026 		kvm_err("kvm: module already exists\n");
1027 		return -EEXIST;
1028 	}
1029 
1030 	return kvm_mips_emulation_init(&kvm_mips_callbacks);
1031 }
1032 
1033 void kvm_arch_exit(void)
1034 {
1035 	kvm_mips_callbacks = NULL;
1036 }
1037 
1038 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
1039 				  struct kvm_sregs *sregs)
1040 {
1041 	return -ENOIOCTLCMD;
1042 }
1043 
1044 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
1045 				  struct kvm_sregs *sregs)
1046 {
1047 	return -ENOIOCTLCMD;
1048 }
1049 
1050 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
1051 {
1052 }
1053 
1054 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1055 {
1056 	return -ENOIOCTLCMD;
1057 }
1058 
1059 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
1060 {
1061 	return -ENOIOCTLCMD;
1062 }
1063 
1064 int kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
1065 {
1066 	return VM_FAULT_SIGBUS;
1067 }
1068 
1069 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
1070 {
1071 	int r;
1072 
1073 	switch (ext) {
1074 	case KVM_CAP_ONE_REG:
1075 	case KVM_CAP_ENABLE_CAP:
1076 		r = 1;
1077 		break;
1078 	case KVM_CAP_COALESCED_MMIO:
1079 		r = KVM_COALESCED_MMIO_PAGE_OFFSET;
1080 		break;
1081 	case KVM_CAP_MIPS_FPU:
1082 		r = !!cpu_has_fpu;
1083 		break;
1084 	case KVM_CAP_MIPS_MSA:
1085 		/*
1086 		 * We don't support MSA vector partitioning yet:
1087 		 * 1) It would require explicit support which can't be tested
1088 		 *    yet due to lack of support in current hardware.
1089 		 * 2) It extends the state that would need to be saved/restored
1090 		 *    by e.g. QEMU for migration.
1091 		 *
1092 		 * When vector partitioning hardware becomes available, support
1093 		 * could be added by requiring a flag when enabling
1094 		 * KVM_CAP_MIPS_MSA capability to indicate that userland knows
1095 		 * to save/restore the appropriate extra state.
1096 		 */
1097 		r = cpu_has_msa && !(boot_cpu_data.msa_id & MSA_IR_WRPF);
1098 		break;
1099 	default:
1100 		r = 0;
1101 		break;
1102 	}
1103 	return r;
1104 }
1105 
1106 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
1107 {
1108 	return kvm_mips_pending_timer(vcpu);
1109 }
1110 
1111 int kvm_arch_vcpu_dump_regs(struct kvm_vcpu *vcpu)
1112 {
1113 	int i;
1114 	struct mips_coproc *cop0;
1115 
1116 	if (!vcpu)
1117 		return -1;
1118 
1119 	kvm_debug("VCPU Register Dump:\n");
1120 	kvm_debug("\tpc = 0x%08lx\n", vcpu->arch.pc);
1121 	kvm_debug("\texceptions: %08lx\n", vcpu->arch.pending_exceptions);
1122 
1123 	for (i = 0; i < 32; i += 4) {
1124 		kvm_debug("\tgpr%02d: %08lx %08lx %08lx %08lx\n", i,
1125 		       vcpu->arch.gprs[i],
1126 		       vcpu->arch.gprs[i + 1],
1127 		       vcpu->arch.gprs[i + 2], vcpu->arch.gprs[i + 3]);
1128 	}
1129 	kvm_debug("\thi: 0x%08lx\n", vcpu->arch.hi);
1130 	kvm_debug("\tlo: 0x%08lx\n", vcpu->arch.lo);
1131 
1132 	cop0 = vcpu->arch.cop0;
1133 	kvm_debug("\tStatus: 0x%08lx, Cause: 0x%08lx\n",
1134 		  kvm_read_c0_guest_status(cop0),
1135 		  kvm_read_c0_guest_cause(cop0));
1136 
1137 	kvm_debug("\tEPC: 0x%08lx\n", kvm_read_c0_guest_epc(cop0));
1138 
1139 	return 0;
1140 }
1141 
1142 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1143 {
1144 	int i;
1145 
1146 	for (i = 1; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1147 		vcpu->arch.gprs[i] = regs->gpr[i];
1148 	vcpu->arch.gprs[0] = 0; /* zero is special, and cannot be set. */
1149 	vcpu->arch.hi = regs->hi;
1150 	vcpu->arch.lo = regs->lo;
1151 	vcpu->arch.pc = regs->pc;
1152 
1153 	return 0;
1154 }
1155 
1156 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
1157 {
1158 	int i;
1159 
1160 	for (i = 0; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
1161 		regs->gpr[i] = vcpu->arch.gprs[i];
1162 
1163 	regs->hi = vcpu->arch.hi;
1164 	regs->lo = vcpu->arch.lo;
1165 	regs->pc = vcpu->arch.pc;
1166 
1167 	return 0;
1168 }
1169 
1170 static void kvm_mips_comparecount_func(unsigned long data)
1171 {
1172 	struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data;
1173 
1174 	kvm_mips_callbacks->queue_timer_int(vcpu);
1175 
1176 	vcpu->arch.wait = 0;
1177 	if (waitqueue_active(&vcpu->wq))
1178 		wake_up_interruptible(&vcpu->wq);
1179 }
1180 
1181 /* low level hrtimer wake routine */
1182 static enum hrtimer_restart kvm_mips_comparecount_wakeup(struct hrtimer *timer)
1183 {
1184 	struct kvm_vcpu *vcpu;
1185 
1186 	vcpu = container_of(timer, struct kvm_vcpu, arch.comparecount_timer);
1187 	kvm_mips_comparecount_func((unsigned long) vcpu);
1188 	return kvm_mips_count_timeout(vcpu);
1189 }
1190 
1191 int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
1192 {
1193 	kvm_mips_callbacks->vcpu_init(vcpu);
1194 	hrtimer_init(&vcpu->arch.comparecount_timer, CLOCK_MONOTONIC,
1195 		     HRTIMER_MODE_REL);
1196 	vcpu->arch.comparecount_timer.function = kvm_mips_comparecount_wakeup;
1197 	return 0;
1198 }
1199 
1200 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
1201 				  struct kvm_translation *tr)
1202 {
1203 	return 0;
1204 }
1205 
1206 /* Initial guest state */
1207 int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
1208 {
1209 	return kvm_mips_callbacks->vcpu_setup(vcpu);
1210 }
1211 
1212 static void kvm_mips_set_c0_status(void)
1213 {
1214 	uint32_t status = read_c0_status();
1215 
1216 	if (cpu_has_dsp)
1217 		status |= (ST0_MX);
1218 
1219 	write_c0_status(status);
1220 	ehb();
1221 }
1222 
1223 /*
1224  * Return value is in the form (errcode<<2 | RESUME_FLAG_HOST | RESUME_FLAG_NV)
1225  */
1226 int kvm_mips_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu)
1227 {
1228 	uint32_t cause = vcpu->arch.host_cp0_cause;
1229 	uint32_t exccode = (cause >> CAUSEB_EXCCODE) & 0x1f;
1230 	uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
1231 	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
1232 	enum emulation_result er = EMULATE_DONE;
1233 	int ret = RESUME_GUEST;
1234 
1235 	/* re-enable HTW before enabling interrupts */
1236 	htw_start();
1237 
1238 	/* Set a default exit reason */
1239 	run->exit_reason = KVM_EXIT_UNKNOWN;
1240 	run->ready_for_interrupt_injection = 1;
1241 
1242 	/*
1243 	 * Set the appropriate status bits based on host CPU features,
1244 	 * before we hit the scheduler
1245 	 */
1246 	kvm_mips_set_c0_status();
1247 
1248 	local_irq_enable();
1249 
1250 	kvm_debug("kvm_mips_handle_exit: cause: %#x, PC: %p, kvm_run: %p, kvm_vcpu: %p\n",
1251 			cause, opc, run, vcpu);
1252 
1253 	/*
1254 	 * Do a privilege check, if in UM most of these exit conditions end up
1255 	 * causing an exception to be delivered to the Guest Kernel
1256 	 */
1257 	er = kvm_mips_check_privilege(cause, opc, run, vcpu);
1258 	if (er == EMULATE_PRIV_FAIL) {
1259 		goto skip_emul;
1260 	} else if (er == EMULATE_FAIL) {
1261 		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1262 		ret = RESUME_HOST;
1263 		goto skip_emul;
1264 	}
1265 
1266 	switch (exccode) {
1267 	case EXCCODE_INT:
1268 		kvm_debug("[%d]EXCCODE_INT @ %p\n", vcpu->vcpu_id, opc);
1269 
1270 		++vcpu->stat.int_exits;
1271 		trace_kvm_exit(vcpu, INT_EXITS);
1272 
1273 		if (need_resched())
1274 			cond_resched();
1275 
1276 		ret = RESUME_GUEST;
1277 		break;
1278 
1279 	case EXCCODE_CPU:
1280 		kvm_debug("EXCCODE_CPU: @ PC: %p\n", opc);
1281 
1282 		++vcpu->stat.cop_unusable_exits;
1283 		trace_kvm_exit(vcpu, COP_UNUSABLE_EXITS);
1284 		ret = kvm_mips_callbacks->handle_cop_unusable(vcpu);
1285 		/* XXXKYMA: Might need to return to user space */
1286 		if (run->exit_reason == KVM_EXIT_IRQ_WINDOW_OPEN)
1287 			ret = RESUME_HOST;
1288 		break;
1289 
1290 	case EXCCODE_MOD:
1291 		++vcpu->stat.tlbmod_exits;
1292 		trace_kvm_exit(vcpu, TLBMOD_EXITS);
1293 		ret = kvm_mips_callbacks->handle_tlb_mod(vcpu);
1294 		break;
1295 
1296 	case EXCCODE_TLBS:
1297 		kvm_debug("TLB ST fault:  cause %#x, status %#lx, PC: %p, BadVaddr: %#lx\n",
1298 			  cause, kvm_read_c0_guest_status(vcpu->arch.cop0), opc,
1299 			  badvaddr);
1300 
1301 		++vcpu->stat.tlbmiss_st_exits;
1302 		trace_kvm_exit(vcpu, TLBMISS_ST_EXITS);
1303 		ret = kvm_mips_callbacks->handle_tlb_st_miss(vcpu);
1304 		break;
1305 
1306 	case EXCCODE_TLBL:
1307 		kvm_debug("TLB LD fault: cause %#x, PC: %p, BadVaddr: %#lx\n",
1308 			  cause, opc, badvaddr);
1309 
1310 		++vcpu->stat.tlbmiss_ld_exits;
1311 		trace_kvm_exit(vcpu, TLBMISS_LD_EXITS);
1312 		ret = kvm_mips_callbacks->handle_tlb_ld_miss(vcpu);
1313 		break;
1314 
1315 	case EXCCODE_ADES:
1316 		++vcpu->stat.addrerr_st_exits;
1317 		trace_kvm_exit(vcpu, ADDRERR_ST_EXITS);
1318 		ret = kvm_mips_callbacks->handle_addr_err_st(vcpu);
1319 		break;
1320 
1321 	case EXCCODE_ADEL:
1322 		++vcpu->stat.addrerr_ld_exits;
1323 		trace_kvm_exit(vcpu, ADDRERR_LD_EXITS);
1324 		ret = kvm_mips_callbacks->handle_addr_err_ld(vcpu);
1325 		break;
1326 
1327 	case EXCCODE_SYS:
1328 		++vcpu->stat.syscall_exits;
1329 		trace_kvm_exit(vcpu, SYSCALL_EXITS);
1330 		ret = kvm_mips_callbacks->handle_syscall(vcpu);
1331 		break;
1332 
1333 	case EXCCODE_RI:
1334 		++vcpu->stat.resvd_inst_exits;
1335 		trace_kvm_exit(vcpu, RESVD_INST_EXITS);
1336 		ret = kvm_mips_callbacks->handle_res_inst(vcpu);
1337 		break;
1338 
1339 	case EXCCODE_BP:
1340 		++vcpu->stat.break_inst_exits;
1341 		trace_kvm_exit(vcpu, BREAK_INST_EXITS);
1342 		ret = kvm_mips_callbacks->handle_break(vcpu);
1343 		break;
1344 
1345 	case EXCCODE_TR:
1346 		++vcpu->stat.trap_inst_exits;
1347 		trace_kvm_exit(vcpu, TRAP_INST_EXITS);
1348 		ret = kvm_mips_callbacks->handle_trap(vcpu);
1349 		break;
1350 
1351 	case EXCCODE_MSAFPE:
1352 		++vcpu->stat.msa_fpe_exits;
1353 		trace_kvm_exit(vcpu, MSA_FPE_EXITS);
1354 		ret = kvm_mips_callbacks->handle_msa_fpe(vcpu);
1355 		break;
1356 
1357 	case EXCCODE_FPE:
1358 		++vcpu->stat.fpe_exits;
1359 		trace_kvm_exit(vcpu, FPE_EXITS);
1360 		ret = kvm_mips_callbacks->handle_fpe(vcpu);
1361 		break;
1362 
1363 	case EXCCODE_MSADIS:
1364 		++vcpu->stat.msa_disabled_exits;
1365 		trace_kvm_exit(vcpu, MSA_DISABLED_EXITS);
1366 		ret = kvm_mips_callbacks->handle_msa_disabled(vcpu);
1367 		break;
1368 
1369 	default:
1370 		kvm_err("Exception Code: %d, not yet handled, @ PC: %p, inst: 0x%08x  BadVaddr: %#lx Status: %#lx\n",
1371 			exccode, opc, kvm_get_inst(opc, vcpu), badvaddr,
1372 			kvm_read_c0_guest_status(vcpu->arch.cop0));
1373 		kvm_arch_vcpu_dump_regs(vcpu);
1374 		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
1375 		ret = RESUME_HOST;
1376 		break;
1377 
1378 	}
1379 
1380 skip_emul:
1381 	local_irq_disable();
1382 
1383 	if (er == EMULATE_DONE && !(ret & RESUME_HOST))
1384 		kvm_mips_deliver_interrupts(vcpu, cause);
1385 
1386 	if (!(ret & RESUME_HOST)) {
1387 		/* Only check for signals if not already exiting to userspace */
1388 		if (signal_pending(current)) {
1389 			run->exit_reason = KVM_EXIT_INTR;
1390 			ret = (-EINTR << 2) | RESUME_HOST;
1391 			++vcpu->stat.signal_exits;
1392 			trace_kvm_exit(vcpu, SIGNAL_EXITS);
1393 		}
1394 	}
1395 
1396 	if (ret == RESUME_GUEST) {
1397 		/*
1398 		 * If FPU / MSA are enabled (i.e. the guest's FPU / MSA context
1399 		 * is live), restore FCR31 / MSACSR.
1400 		 *
1401 		 * This should be before returning to the guest exception
1402 		 * vector, as it may well cause an [MSA] FP exception if there
1403 		 * are pending exception bits unmasked. (see
1404 		 * kvm_mips_csr_die_notifier() for how that is handled).
1405 		 */
1406 		if (kvm_mips_guest_has_fpu(&vcpu->arch) &&
1407 		    read_c0_status() & ST0_CU1)
1408 			__kvm_restore_fcsr(&vcpu->arch);
1409 
1410 		if (kvm_mips_guest_has_msa(&vcpu->arch) &&
1411 		    read_c0_config5() & MIPS_CONF5_MSAEN)
1412 			__kvm_restore_msacsr(&vcpu->arch);
1413 	}
1414 
1415 	/* Disable HTW before returning to guest or host */
1416 	htw_stop();
1417 
1418 	return ret;
1419 }
1420 
1421 /* Enable FPU for guest and restore context */
1422 void kvm_own_fpu(struct kvm_vcpu *vcpu)
1423 {
1424 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1425 	unsigned int sr, cfg5;
1426 
1427 	preempt_disable();
1428 
1429 	sr = kvm_read_c0_guest_status(cop0);
1430 
1431 	/*
1432 	 * If MSA state is already live, it is undefined how it interacts with
1433 	 * FR=0 FPU state, and we don't want to hit reserved instruction
1434 	 * exceptions trying to save the MSA state later when CU=1 && FR=1, so
1435 	 * play it safe and save it first.
1436 	 *
1437 	 * In theory we shouldn't ever hit this case since kvm_lose_fpu() should
1438 	 * get called when guest CU1 is set, however we can't trust the guest
1439 	 * not to clobber the status register directly via the commpage.
1440 	 */
1441 	if (cpu_has_msa && sr & ST0_CU1 && !(sr & ST0_FR) &&
1442 	    vcpu->arch.fpu_inuse & KVM_MIPS_FPU_MSA)
1443 		kvm_lose_fpu(vcpu);
1444 
1445 	/*
1446 	 * Enable FPU for guest
1447 	 * We set FR and FRE according to guest context
1448 	 */
1449 	change_c0_status(ST0_CU1 | ST0_FR, sr);
1450 	if (cpu_has_fre) {
1451 		cfg5 = kvm_read_c0_guest_config5(cop0);
1452 		change_c0_config5(MIPS_CONF5_FRE, cfg5);
1453 	}
1454 	enable_fpu_hazard();
1455 
1456 	/* If guest FPU state not active, restore it now */
1457 	if (!(vcpu->arch.fpu_inuse & KVM_MIPS_FPU_FPU)) {
1458 		__kvm_restore_fpu(&vcpu->arch);
1459 		vcpu->arch.fpu_inuse |= KVM_MIPS_FPU_FPU;
1460 	}
1461 
1462 	preempt_enable();
1463 }
1464 
1465 #ifdef CONFIG_CPU_HAS_MSA
1466 /* Enable MSA for guest and restore context */
1467 void kvm_own_msa(struct kvm_vcpu *vcpu)
1468 {
1469 	struct mips_coproc *cop0 = vcpu->arch.cop0;
1470 	unsigned int sr, cfg5;
1471 
1472 	preempt_disable();
1473 
1474 	/*
1475 	 * Enable FPU if enabled in guest, since we're restoring FPU context
1476 	 * anyway. We set FR and FRE according to guest context.
1477 	 */
1478 	if (kvm_mips_guest_has_fpu(&vcpu->arch)) {
1479 		sr = kvm_read_c0_guest_status(cop0);
1480 
1481 		/*
1482 		 * If FR=0 FPU state is already live, it is undefined how it
1483 		 * interacts with MSA state, so play it safe and save it first.
1484 		 */
1485 		if (!(sr & ST0_FR) &&
1486 		    (vcpu->arch.fpu_inuse & (KVM_MIPS_FPU_FPU |
1487 				KVM_MIPS_FPU_MSA)) == KVM_MIPS_FPU_FPU)
1488 			kvm_lose_fpu(vcpu);
1489 
1490 		change_c0_status(ST0_CU1 | ST0_FR, sr);
1491 		if (sr & ST0_CU1 && cpu_has_fre) {
1492 			cfg5 = kvm_read_c0_guest_config5(cop0);
1493 			change_c0_config5(MIPS_CONF5_FRE, cfg5);
1494 		}
1495 	}
1496 
1497 	/* Enable MSA for guest */
1498 	set_c0_config5(MIPS_CONF5_MSAEN);
1499 	enable_fpu_hazard();
1500 
1501 	switch (vcpu->arch.fpu_inuse & (KVM_MIPS_FPU_FPU | KVM_MIPS_FPU_MSA)) {
1502 	case KVM_MIPS_FPU_FPU:
1503 		/*
1504 		 * Guest FPU state already loaded, only restore upper MSA state
1505 		 */
1506 		__kvm_restore_msa_upper(&vcpu->arch);
1507 		vcpu->arch.fpu_inuse |= KVM_MIPS_FPU_MSA;
1508 		break;
1509 	case 0:
1510 		/* Neither FPU or MSA already active, restore full MSA state */
1511 		__kvm_restore_msa(&vcpu->arch);
1512 		vcpu->arch.fpu_inuse |= KVM_MIPS_FPU_MSA;
1513 		if (kvm_mips_guest_has_fpu(&vcpu->arch))
1514 			vcpu->arch.fpu_inuse |= KVM_MIPS_FPU_FPU;
1515 		break;
1516 	default:
1517 		break;
1518 	}
1519 
1520 	preempt_enable();
1521 }
1522 #endif
1523 
1524 /* Drop FPU & MSA without saving it */
1525 void kvm_drop_fpu(struct kvm_vcpu *vcpu)
1526 {
1527 	preempt_disable();
1528 	if (cpu_has_msa && vcpu->arch.fpu_inuse & KVM_MIPS_FPU_MSA) {
1529 		disable_msa();
1530 		vcpu->arch.fpu_inuse &= ~KVM_MIPS_FPU_MSA;
1531 	}
1532 	if (vcpu->arch.fpu_inuse & KVM_MIPS_FPU_FPU) {
1533 		clear_c0_status(ST0_CU1 | ST0_FR);
1534 		vcpu->arch.fpu_inuse &= ~KVM_MIPS_FPU_FPU;
1535 	}
1536 	preempt_enable();
1537 }
1538 
1539 /* Save and disable FPU & MSA */
1540 void kvm_lose_fpu(struct kvm_vcpu *vcpu)
1541 {
1542 	/*
1543 	 * FPU & MSA get disabled in root context (hardware) when it is disabled
1544 	 * in guest context (software), but the register state in the hardware
1545 	 * may still be in use. This is why we explicitly re-enable the hardware
1546 	 * before saving.
1547 	 */
1548 
1549 	preempt_disable();
1550 	if (cpu_has_msa && vcpu->arch.fpu_inuse & KVM_MIPS_FPU_MSA) {
1551 		set_c0_config5(MIPS_CONF5_MSAEN);
1552 		enable_fpu_hazard();
1553 
1554 		__kvm_save_msa(&vcpu->arch);
1555 
1556 		/* Disable MSA & FPU */
1557 		disable_msa();
1558 		if (vcpu->arch.fpu_inuse & KVM_MIPS_FPU_FPU)
1559 			clear_c0_status(ST0_CU1 | ST0_FR);
1560 		vcpu->arch.fpu_inuse &= ~(KVM_MIPS_FPU_FPU | KVM_MIPS_FPU_MSA);
1561 	} else if (vcpu->arch.fpu_inuse & KVM_MIPS_FPU_FPU) {
1562 		set_c0_status(ST0_CU1);
1563 		enable_fpu_hazard();
1564 
1565 		__kvm_save_fpu(&vcpu->arch);
1566 		vcpu->arch.fpu_inuse &= ~KVM_MIPS_FPU_FPU;
1567 
1568 		/* Disable FPU */
1569 		clear_c0_status(ST0_CU1 | ST0_FR);
1570 	}
1571 	preempt_enable();
1572 }
1573 
1574 /*
1575  * Step over a specific ctc1 to FCSR and a specific ctcmsa to MSACSR which are
1576  * used to restore guest FCSR/MSACSR state and may trigger a "harmless" FP/MSAFP
1577  * exception if cause bits are set in the value being written.
1578  */
1579 static int kvm_mips_csr_die_notify(struct notifier_block *self,
1580 				   unsigned long cmd, void *ptr)
1581 {
1582 	struct die_args *args = (struct die_args *)ptr;
1583 	struct pt_regs *regs = args->regs;
1584 	unsigned long pc;
1585 
1586 	/* Only interested in FPE and MSAFPE */
1587 	if (cmd != DIE_FP && cmd != DIE_MSAFP)
1588 		return NOTIFY_DONE;
1589 
1590 	/* Return immediately if guest context isn't active */
1591 	if (!(current->flags & PF_VCPU))
1592 		return NOTIFY_DONE;
1593 
1594 	/* Should never get here from user mode */
1595 	BUG_ON(user_mode(regs));
1596 
1597 	pc = instruction_pointer(regs);
1598 	switch (cmd) {
1599 	case DIE_FP:
1600 		/* match 2nd instruction in __kvm_restore_fcsr */
1601 		if (pc != (unsigned long)&__kvm_restore_fcsr + 4)
1602 			return NOTIFY_DONE;
1603 		break;
1604 	case DIE_MSAFP:
1605 		/* match 2nd/3rd instruction in __kvm_restore_msacsr */
1606 		if (!cpu_has_msa ||
1607 		    pc < (unsigned long)&__kvm_restore_msacsr + 4 ||
1608 		    pc > (unsigned long)&__kvm_restore_msacsr + 8)
1609 			return NOTIFY_DONE;
1610 		break;
1611 	}
1612 
1613 	/* Move PC forward a little and continue executing */
1614 	instruction_pointer(regs) += 4;
1615 
1616 	return NOTIFY_STOP;
1617 }
1618 
1619 static struct notifier_block kvm_mips_csr_die_notifier = {
1620 	.notifier_call = kvm_mips_csr_die_notify,
1621 };
1622 
1623 static int __init kvm_mips_init(void)
1624 {
1625 	int ret;
1626 
1627 	ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
1628 
1629 	if (ret)
1630 		return ret;
1631 
1632 	register_die_notifier(&kvm_mips_csr_die_notifier);
1633 
1634 	/*
1635 	 * On MIPS, kernel modules are executed from "mapped space", which
1636 	 * requires TLBs. The TLB handling code is statically linked with
1637 	 * the rest of the kernel (tlb.c) to avoid the possibility of
1638 	 * double faulting. The issue is that the TLB code references
1639 	 * routines that are part of the the KVM module, which are only
1640 	 * available once the module is loaded.
1641 	 */
1642 	kvm_mips_gfn_to_pfn = gfn_to_pfn;
1643 	kvm_mips_release_pfn_clean = kvm_release_pfn_clean;
1644 	kvm_mips_is_error_pfn = is_error_pfn;
1645 
1646 	return 0;
1647 }
1648 
1649 static void __exit kvm_mips_exit(void)
1650 {
1651 	kvm_exit();
1652 
1653 	kvm_mips_gfn_to_pfn = NULL;
1654 	kvm_mips_release_pfn_clean = NULL;
1655 	kvm_mips_is_error_pfn = NULL;
1656 
1657 	unregister_die_notifier(&kvm_mips_csr_die_notifier);
1658 }
1659 
1660 module_init(kvm_mips_init);
1661 module_exit(kvm_mips_exit);
1662 
1663 EXPORT_TRACEPOINT_SYMBOL(kvm_exit);
1664