xref: /openbmc/linux/arch/x86/kvm/lapic.c (revision 45471cd98decae5fced8b38e46c223f54a924814)
1 
2 /*
3  * Local APIC virtualization
4  *
5  * Copyright (C) 2006 Qumranet, Inc.
6  * Copyright (C) 2007 Novell
7  * Copyright (C) 2007 Intel
8  * Copyright 2009 Red Hat, Inc. and/or its affiliates.
9  *
10  * Authors:
11  *   Dor Laor <dor.laor@qumranet.com>
12  *   Gregory Haskins <ghaskins@novell.com>
13  *   Yaozu (Eddie) Dong <eddie.dong@intel.com>
14  *
15  * Based on Xen 3.1 code, Copyright (c) 2004, Intel Corporation.
16  *
17  * This work is licensed under the terms of the GNU GPL, version 2.  See
18  * the COPYING file in the top-level directory.
19  */
20 
21 #include <linux/kvm_host.h>
22 #include <linux/kvm.h>
23 #include <linux/mm.h>
24 #include <linux/highmem.h>
25 #include <linux/smp.h>
26 #include <linux/hrtimer.h>
27 #include <linux/io.h>
28 #include <linux/module.h>
29 #include <linux/math64.h>
30 #include <linux/slab.h>
31 #include <asm/processor.h>
32 #include <asm/msr.h>
33 #include <asm/page.h>
34 #include <asm/current.h>
35 #include <asm/apicdef.h>
36 #include <asm/delay.h>
37 #include <linux/atomic.h>
38 #include <linux/jump_label.h>
39 #include "kvm_cache_regs.h"
40 #include "irq.h"
41 #include "trace.h"
42 #include "x86.h"
43 #include "cpuid.h"
44 
45 #ifndef CONFIG_X86_64
46 #define mod_64(x, y) ((x) - (y) * div64_u64(x, y))
47 #else
48 #define mod_64(x, y) ((x) % (y))
49 #endif
50 
51 #define PRId64 "d"
52 #define PRIx64 "llx"
53 #define PRIu64 "u"
54 #define PRIo64 "o"
55 
56 #define APIC_BUS_CYCLE_NS 1
57 
58 /* #define apic_debug(fmt,arg...) printk(KERN_WARNING fmt,##arg) */
59 #define apic_debug(fmt, arg...)
60 
61 #define APIC_LVT_NUM			6
62 /* 14 is the version for Xeon and Pentium 8.4.8*/
63 #define APIC_VERSION			(0x14UL | ((APIC_LVT_NUM - 1) << 16))
64 #define LAPIC_MMIO_LENGTH		(1 << 12)
65 /* followed define is not in apicdef.h */
66 #define APIC_SHORT_MASK			0xc0000
67 #define APIC_DEST_NOSHORT		0x0
68 #define APIC_DEST_MASK			0x800
69 #define MAX_APIC_VECTOR			256
70 #define APIC_VECTORS_PER_REG		32
71 
72 #define APIC_BROADCAST			0xFF
73 #define X2APIC_BROADCAST		0xFFFFFFFFul
74 
75 #define VEC_POS(v) ((v) & (32 - 1))
76 #define REG_POS(v) (((v) >> 5) << 4)
77 
78 static inline void apic_set_reg(struct kvm_lapic *apic, int reg_off, u32 val)
79 {
80 	*((u32 *) (apic->regs + reg_off)) = val;
81 }
82 
83 static inline int apic_test_vector(int vec, void *bitmap)
84 {
85 	return test_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
86 }
87 
88 bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector)
89 {
90 	struct kvm_lapic *apic = vcpu->arch.apic;
91 
92 	return apic_test_vector(vector, apic->regs + APIC_ISR) ||
93 		apic_test_vector(vector, apic->regs + APIC_IRR);
94 }
95 
96 static inline void apic_set_vector(int vec, void *bitmap)
97 {
98 	set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
99 }
100 
101 static inline void apic_clear_vector(int vec, void *bitmap)
102 {
103 	clear_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
104 }
105 
106 static inline int __apic_test_and_set_vector(int vec, void *bitmap)
107 {
108 	return __test_and_set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
109 }
110 
111 static inline int __apic_test_and_clear_vector(int vec, void *bitmap)
112 {
113 	return __test_and_clear_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
114 }
115 
116 struct static_key_deferred apic_hw_disabled __read_mostly;
117 struct static_key_deferred apic_sw_disabled __read_mostly;
118 
119 static inline int apic_enabled(struct kvm_lapic *apic)
120 {
121 	return kvm_apic_sw_enabled(apic) &&	kvm_apic_hw_enabled(apic);
122 }
123 
124 #define LVT_MASK	\
125 	(APIC_LVT_MASKED | APIC_SEND_PENDING | APIC_VECTOR_MASK)
126 
127 #define LINT_MASK	\
128 	(LVT_MASK | APIC_MODE_MASK | APIC_INPUT_POLARITY | \
129 	 APIC_LVT_REMOTE_IRR | APIC_LVT_LEVEL_TRIGGER)
130 
131 static inline int kvm_apic_id(struct kvm_lapic *apic)
132 {
133 	return (kvm_apic_get_reg(apic, APIC_ID) >> 24) & 0xff;
134 }
135 
136 /* The logical map is definitely wrong if we have multiple
137  * modes at the same time.  (Physical map is always right.)
138  */
139 static inline bool kvm_apic_logical_map_valid(struct kvm_apic_map *map)
140 {
141 	return !(map->mode & (map->mode - 1));
142 }
143 
144 static inline void
145 apic_logical_id(struct kvm_apic_map *map, u32 dest_id, u16 *cid, u16 *lid)
146 {
147 	unsigned lid_bits;
148 
149 	BUILD_BUG_ON(KVM_APIC_MODE_XAPIC_CLUSTER !=  4);
150 	BUILD_BUG_ON(KVM_APIC_MODE_XAPIC_FLAT    !=  8);
151 	BUILD_BUG_ON(KVM_APIC_MODE_X2APIC        != 16);
152 	lid_bits = map->mode;
153 
154 	*cid = dest_id >> lid_bits;
155 	*lid = dest_id & ((1 << lid_bits) - 1);
156 }
157 
158 static void recalculate_apic_map(struct kvm *kvm)
159 {
160 	struct kvm_apic_map *new, *old = NULL;
161 	struct kvm_vcpu *vcpu;
162 	int i;
163 
164 	new = kzalloc(sizeof(struct kvm_apic_map), GFP_KERNEL);
165 
166 	mutex_lock(&kvm->arch.apic_map_lock);
167 
168 	if (!new)
169 		goto out;
170 
171 	kvm_for_each_vcpu(i, vcpu, kvm) {
172 		struct kvm_lapic *apic = vcpu->arch.apic;
173 		u16 cid, lid;
174 		u32 ldr, aid;
175 
176 		if (!kvm_apic_present(vcpu))
177 			continue;
178 
179 		aid = kvm_apic_id(apic);
180 		ldr = kvm_apic_get_reg(apic, APIC_LDR);
181 
182 		if (aid < ARRAY_SIZE(new->phys_map))
183 			new->phys_map[aid] = apic;
184 
185 		if (apic_x2apic_mode(apic)) {
186 			new->mode |= KVM_APIC_MODE_X2APIC;
187 		} else if (ldr) {
188 			ldr = GET_APIC_LOGICAL_ID(ldr);
189 			if (kvm_apic_get_reg(apic, APIC_DFR) == APIC_DFR_FLAT)
190 				new->mode |= KVM_APIC_MODE_XAPIC_FLAT;
191 			else
192 				new->mode |= KVM_APIC_MODE_XAPIC_CLUSTER;
193 		}
194 
195 		if (!kvm_apic_logical_map_valid(new))
196 			continue;
197 
198 		apic_logical_id(new, ldr, &cid, &lid);
199 
200 		if (lid && cid < ARRAY_SIZE(new->logical_map))
201 			new->logical_map[cid][ffs(lid) - 1] = apic;
202 	}
203 out:
204 	old = rcu_dereference_protected(kvm->arch.apic_map,
205 			lockdep_is_held(&kvm->arch.apic_map_lock));
206 	rcu_assign_pointer(kvm->arch.apic_map, new);
207 	mutex_unlock(&kvm->arch.apic_map_lock);
208 
209 	if (old)
210 		kfree_rcu(old, rcu);
211 
212 	kvm_vcpu_request_scan_ioapic(kvm);
213 }
214 
215 static inline void apic_set_spiv(struct kvm_lapic *apic, u32 val)
216 {
217 	bool enabled = val & APIC_SPIV_APIC_ENABLED;
218 
219 	apic_set_reg(apic, APIC_SPIV, val);
220 
221 	if (enabled != apic->sw_enabled) {
222 		apic->sw_enabled = enabled;
223 		if (enabled) {
224 			static_key_slow_dec_deferred(&apic_sw_disabled);
225 			recalculate_apic_map(apic->vcpu->kvm);
226 		} else
227 			static_key_slow_inc(&apic_sw_disabled.key);
228 	}
229 }
230 
231 static inline void kvm_apic_set_id(struct kvm_lapic *apic, u8 id)
232 {
233 	apic_set_reg(apic, APIC_ID, id << 24);
234 	recalculate_apic_map(apic->vcpu->kvm);
235 }
236 
237 static inline void kvm_apic_set_ldr(struct kvm_lapic *apic, u32 id)
238 {
239 	apic_set_reg(apic, APIC_LDR, id);
240 	recalculate_apic_map(apic->vcpu->kvm);
241 }
242 
243 static inline void kvm_apic_set_x2apic_id(struct kvm_lapic *apic, u8 id)
244 {
245 	u32 ldr = ((id >> 4) << 16) | (1 << (id & 0xf));
246 
247 	apic_set_reg(apic, APIC_ID, id << 24);
248 	apic_set_reg(apic, APIC_LDR, ldr);
249 	recalculate_apic_map(apic->vcpu->kvm);
250 }
251 
252 static inline int apic_lvt_enabled(struct kvm_lapic *apic, int lvt_type)
253 {
254 	return !(kvm_apic_get_reg(apic, lvt_type) & APIC_LVT_MASKED);
255 }
256 
257 static inline int apic_lvt_vector(struct kvm_lapic *apic, int lvt_type)
258 {
259 	return kvm_apic_get_reg(apic, lvt_type) & APIC_VECTOR_MASK;
260 }
261 
262 static inline int apic_lvtt_oneshot(struct kvm_lapic *apic)
263 {
264 	return apic->lapic_timer.timer_mode == APIC_LVT_TIMER_ONESHOT;
265 }
266 
267 static inline int apic_lvtt_period(struct kvm_lapic *apic)
268 {
269 	return apic->lapic_timer.timer_mode == APIC_LVT_TIMER_PERIODIC;
270 }
271 
272 static inline int apic_lvtt_tscdeadline(struct kvm_lapic *apic)
273 {
274 	return apic->lapic_timer.timer_mode == APIC_LVT_TIMER_TSCDEADLINE;
275 }
276 
277 static inline int apic_lvt_nmi_mode(u32 lvt_val)
278 {
279 	return (lvt_val & (APIC_MODE_MASK | APIC_LVT_MASKED)) == APIC_DM_NMI;
280 }
281 
282 void kvm_apic_set_version(struct kvm_vcpu *vcpu)
283 {
284 	struct kvm_lapic *apic = vcpu->arch.apic;
285 	struct kvm_cpuid_entry2 *feat;
286 	u32 v = APIC_VERSION;
287 
288 	if (!kvm_vcpu_has_lapic(vcpu))
289 		return;
290 
291 	feat = kvm_find_cpuid_entry(apic->vcpu, 0x1, 0);
292 	if (feat && (feat->ecx & (1 << (X86_FEATURE_X2APIC & 31))))
293 		v |= APIC_LVR_DIRECTED_EOI;
294 	apic_set_reg(apic, APIC_LVR, v);
295 }
296 
297 static const unsigned int apic_lvt_mask[APIC_LVT_NUM] = {
298 	LVT_MASK ,      /* part LVTT mask, timer mode mask added at runtime */
299 	LVT_MASK | APIC_MODE_MASK,	/* LVTTHMR */
300 	LVT_MASK | APIC_MODE_MASK,	/* LVTPC */
301 	LINT_MASK, LINT_MASK,	/* LVT0-1 */
302 	LVT_MASK		/* LVTERR */
303 };
304 
305 static int find_highest_vector(void *bitmap)
306 {
307 	int vec;
308 	u32 *reg;
309 
310 	for (vec = MAX_APIC_VECTOR - APIC_VECTORS_PER_REG;
311 	     vec >= 0; vec -= APIC_VECTORS_PER_REG) {
312 		reg = bitmap + REG_POS(vec);
313 		if (*reg)
314 			return fls(*reg) - 1 + vec;
315 	}
316 
317 	return -1;
318 }
319 
320 static u8 count_vectors(void *bitmap)
321 {
322 	int vec;
323 	u32 *reg;
324 	u8 count = 0;
325 
326 	for (vec = 0; vec < MAX_APIC_VECTOR; vec += APIC_VECTORS_PER_REG) {
327 		reg = bitmap + REG_POS(vec);
328 		count += hweight32(*reg);
329 	}
330 
331 	return count;
332 }
333 
334 void __kvm_apic_update_irr(u32 *pir, void *regs)
335 {
336 	u32 i, pir_val;
337 
338 	for (i = 0; i <= 7; i++) {
339 		pir_val = xchg(&pir[i], 0);
340 		if (pir_val)
341 			*((u32 *)(regs + APIC_IRR + i * 0x10)) |= pir_val;
342 	}
343 }
344 EXPORT_SYMBOL_GPL(__kvm_apic_update_irr);
345 
346 void kvm_apic_update_irr(struct kvm_vcpu *vcpu, u32 *pir)
347 {
348 	struct kvm_lapic *apic = vcpu->arch.apic;
349 
350 	__kvm_apic_update_irr(pir, apic->regs);
351 }
352 EXPORT_SYMBOL_GPL(kvm_apic_update_irr);
353 
354 static inline void apic_set_irr(int vec, struct kvm_lapic *apic)
355 {
356 	apic_set_vector(vec, apic->regs + APIC_IRR);
357 	/*
358 	 * irr_pending must be true if any interrupt is pending; set it after
359 	 * APIC_IRR to avoid race with apic_clear_irr
360 	 */
361 	apic->irr_pending = true;
362 }
363 
364 static inline int apic_search_irr(struct kvm_lapic *apic)
365 {
366 	return find_highest_vector(apic->regs + APIC_IRR);
367 }
368 
369 static inline int apic_find_highest_irr(struct kvm_lapic *apic)
370 {
371 	int result;
372 
373 	/*
374 	 * Note that irr_pending is just a hint. It will be always
375 	 * true with virtual interrupt delivery enabled.
376 	 */
377 	if (!apic->irr_pending)
378 		return -1;
379 
380 	kvm_x86_ops->sync_pir_to_irr(apic->vcpu);
381 	result = apic_search_irr(apic);
382 	ASSERT(result == -1 || result >= 16);
383 
384 	return result;
385 }
386 
387 static inline void apic_clear_irr(int vec, struct kvm_lapic *apic)
388 {
389 	struct kvm_vcpu *vcpu;
390 
391 	vcpu = apic->vcpu;
392 
393 	if (unlikely(kvm_apic_vid_enabled(vcpu->kvm))) {
394 		/* try to update RVI */
395 		apic_clear_vector(vec, apic->regs + APIC_IRR);
396 		kvm_make_request(KVM_REQ_EVENT, vcpu);
397 	} else {
398 		apic->irr_pending = false;
399 		apic_clear_vector(vec, apic->regs + APIC_IRR);
400 		if (apic_search_irr(apic) != -1)
401 			apic->irr_pending = true;
402 	}
403 }
404 
405 static inline void apic_set_isr(int vec, struct kvm_lapic *apic)
406 {
407 	struct kvm_vcpu *vcpu;
408 
409 	if (__apic_test_and_set_vector(vec, apic->regs + APIC_ISR))
410 		return;
411 
412 	vcpu = apic->vcpu;
413 
414 	/*
415 	 * With APIC virtualization enabled, all caching is disabled
416 	 * because the processor can modify ISR under the hood.  Instead
417 	 * just set SVI.
418 	 */
419 	if (unlikely(kvm_x86_ops->hwapic_isr_update))
420 		kvm_x86_ops->hwapic_isr_update(vcpu->kvm, vec);
421 	else {
422 		++apic->isr_count;
423 		BUG_ON(apic->isr_count > MAX_APIC_VECTOR);
424 		/*
425 		 * ISR (in service register) bit is set when injecting an interrupt.
426 		 * The highest vector is injected. Thus the latest bit set matches
427 		 * the highest bit in ISR.
428 		 */
429 		apic->highest_isr_cache = vec;
430 	}
431 }
432 
433 static inline int apic_find_highest_isr(struct kvm_lapic *apic)
434 {
435 	int result;
436 
437 	/*
438 	 * Note that isr_count is always 1, and highest_isr_cache
439 	 * is always -1, with APIC virtualization enabled.
440 	 */
441 	if (!apic->isr_count)
442 		return -1;
443 	if (likely(apic->highest_isr_cache != -1))
444 		return apic->highest_isr_cache;
445 
446 	result = find_highest_vector(apic->regs + APIC_ISR);
447 	ASSERT(result == -1 || result >= 16);
448 
449 	return result;
450 }
451 
452 static inline void apic_clear_isr(int vec, struct kvm_lapic *apic)
453 {
454 	struct kvm_vcpu *vcpu;
455 	if (!__apic_test_and_clear_vector(vec, apic->regs + APIC_ISR))
456 		return;
457 
458 	vcpu = apic->vcpu;
459 
460 	/*
461 	 * We do get here for APIC virtualization enabled if the guest
462 	 * uses the Hyper-V APIC enlightenment.  In this case we may need
463 	 * to trigger a new interrupt delivery by writing the SVI field;
464 	 * on the other hand isr_count and highest_isr_cache are unused
465 	 * and must be left alone.
466 	 */
467 	if (unlikely(kvm_x86_ops->hwapic_isr_update))
468 		kvm_x86_ops->hwapic_isr_update(vcpu->kvm,
469 					       apic_find_highest_isr(apic));
470 	else {
471 		--apic->isr_count;
472 		BUG_ON(apic->isr_count < 0);
473 		apic->highest_isr_cache = -1;
474 	}
475 }
476 
477 int kvm_lapic_find_highest_irr(struct kvm_vcpu *vcpu)
478 {
479 	int highest_irr;
480 
481 	/* This may race with setting of irr in __apic_accept_irq() and
482 	 * value returned may be wrong, but kvm_vcpu_kick() in __apic_accept_irq
483 	 * will cause vmexit immediately and the value will be recalculated
484 	 * on the next vmentry.
485 	 */
486 	if (!kvm_vcpu_has_lapic(vcpu))
487 		return 0;
488 	highest_irr = apic_find_highest_irr(vcpu->arch.apic);
489 
490 	return highest_irr;
491 }
492 
493 static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode,
494 			     int vector, int level, int trig_mode,
495 			     unsigned long *dest_map);
496 
497 int kvm_apic_set_irq(struct kvm_vcpu *vcpu, struct kvm_lapic_irq *irq,
498 		unsigned long *dest_map)
499 {
500 	struct kvm_lapic *apic = vcpu->arch.apic;
501 
502 	return __apic_accept_irq(apic, irq->delivery_mode, irq->vector,
503 			irq->level, irq->trig_mode, dest_map);
504 }
505 
506 static int pv_eoi_put_user(struct kvm_vcpu *vcpu, u8 val)
507 {
508 
509 	return kvm_write_guest_cached(vcpu->kvm, &vcpu->arch.pv_eoi.data, &val,
510 				      sizeof(val));
511 }
512 
513 static int pv_eoi_get_user(struct kvm_vcpu *vcpu, u8 *val)
514 {
515 
516 	return kvm_read_guest_cached(vcpu->kvm, &vcpu->arch.pv_eoi.data, val,
517 				      sizeof(*val));
518 }
519 
520 static inline bool pv_eoi_enabled(struct kvm_vcpu *vcpu)
521 {
522 	return vcpu->arch.pv_eoi.msr_val & KVM_MSR_ENABLED;
523 }
524 
525 static bool pv_eoi_get_pending(struct kvm_vcpu *vcpu)
526 {
527 	u8 val;
528 	if (pv_eoi_get_user(vcpu, &val) < 0)
529 		apic_debug("Can't read EOI MSR value: 0x%llx\n",
530 			   (unsigned long long)vcpu->arch.pv_eoi.msr_val);
531 	return val & 0x1;
532 }
533 
534 static void pv_eoi_set_pending(struct kvm_vcpu *vcpu)
535 {
536 	if (pv_eoi_put_user(vcpu, KVM_PV_EOI_ENABLED) < 0) {
537 		apic_debug("Can't set EOI MSR value: 0x%llx\n",
538 			   (unsigned long long)vcpu->arch.pv_eoi.msr_val);
539 		return;
540 	}
541 	__set_bit(KVM_APIC_PV_EOI_PENDING, &vcpu->arch.apic_attention);
542 }
543 
544 static void pv_eoi_clr_pending(struct kvm_vcpu *vcpu)
545 {
546 	if (pv_eoi_put_user(vcpu, KVM_PV_EOI_DISABLED) < 0) {
547 		apic_debug("Can't clear EOI MSR value: 0x%llx\n",
548 			   (unsigned long long)vcpu->arch.pv_eoi.msr_val);
549 		return;
550 	}
551 	__clear_bit(KVM_APIC_PV_EOI_PENDING, &vcpu->arch.apic_attention);
552 }
553 
554 void kvm_apic_update_tmr(struct kvm_vcpu *vcpu, u32 *tmr)
555 {
556 	struct kvm_lapic *apic = vcpu->arch.apic;
557 	int i;
558 
559 	for (i = 0; i < 8; i++)
560 		apic_set_reg(apic, APIC_TMR + 0x10 * i, tmr[i]);
561 }
562 
563 static void apic_update_ppr(struct kvm_lapic *apic)
564 {
565 	u32 tpr, isrv, ppr, old_ppr;
566 	int isr;
567 
568 	old_ppr = kvm_apic_get_reg(apic, APIC_PROCPRI);
569 	tpr = kvm_apic_get_reg(apic, APIC_TASKPRI);
570 	isr = apic_find_highest_isr(apic);
571 	isrv = (isr != -1) ? isr : 0;
572 
573 	if ((tpr & 0xf0) >= (isrv & 0xf0))
574 		ppr = tpr & 0xff;
575 	else
576 		ppr = isrv & 0xf0;
577 
578 	apic_debug("vlapic %p, ppr 0x%x, isr 0x%x, isrv 0x%x",
579 		   apic, ppr, isr, isrv);
580 
581 	if (old_ppr != ppr) {
582 		apic_set_reg(apic, APIC_PROCPRI, ppr);
583 		if (ppr < old_ppr)
584 			kvm_make_request(KVM_REQ_EVENT, apic->vcpu);
585 	}
586 }
587 
588 static void apic_set_tpr(struct kvm_lapic *apic, u32 tpr)
589 {
590 	apic_set_reg(apic, APIC_TASKPRI, tpr);
591 	apic_update_ppr(apic);
592 }
593 
594 static bool kvm_apic_broadcast(struct kvm_lapic *apic, u32 mda)
595 {
596 	if (apic_x2apic_mode(apic))
597 		return mda == X2APIC_BROADCAST;
598 
599 	return GET_APIC_DEST_FIELD(mda) == APIC_BROADCAST;
600 }
601 
602 static bool kvm_apic_match_physical_addr(struct kvm_lapic *apic, u32 mda)
603 {
604 	if (kvm_apic_broadcast(apic, mda))
605 		return true;
606 
607 	if (apic_x2apic_mode(apic))
608 		return mda == kvm_apic_id(apic);
609 
610 	return mda == SET_APIC_DEST_FIELD(kvm_apic_id(apic));
611 }
612 
613 static bool kvm_apic_match_logical_addr(struct kvm_lapic *apic, u32 mda)
614 {
615 	u32 logical_id;
616 
617 	if (kvm_apic_broadcast(apic, mda))
618 		return true;
619 
620 	logical_id = kvm_apic_get_reg(apic, APIC_LDR);
621 
622 	if (apic_x2apic_mode(apic))
623 		return ((logical_id >> 16) == (mda >> 16))
624 		       && (logical_id & mda & 0xffff) != 0;
625 
626 	logical_id = GET_APIC_LOGICAL_ID(logical_id);
627 	mda = GET_APIC_DEST_FIELD(mda);
628 
629 	switch (kvm_apic_get_reg(apic, APIC_DFR)) {
630 	case APIC_DFR_FLAT:
631 		return (logical_id & mda) != 0;
632 	case APIC_DFR_CLUSTER:
633 		return ((logical_id >> 4) == (mda >> 4))
634 		       && (logical_id & mda & 0xf) != 0;
635 	default:
636 		apic_debug("Bad DFR vcpu %d: %08x\n",
637 			   apic->vcpu->vcpu_id, kvm_apic_get_reg(apic, APIC_DFR));
638 		return false;
639 	}
640 }
641 
642 /* KVM APIC implementation has two quirks
643  *  - dest always begins at 0 while xAPIC MDA has offset 24,
644  *  - IOxAPIC messages have to be delivered (directly) to x2APIC.
645  */
646 static u32 kvm_apic_mda(unsigned int dest_id, struct kvm_lapic *source,
647                                               struct kvm_lapic *target)
648 {
649 	bool ipi = source != NULL;
650 	bool x2apic_mda = apic_x2apic_mode(ipi ? source : target);
651 
652 	if (!ipi && dest_id == APIC_BROADCAST && x2apic_mda)
653 		return X2APIC_BROADCAST;
654 
655 	return x2apic_mda ? dest_id : SET_APIC_DEST_FIELD(dest_id);
656 }
657 
658 bool kvm_apic_match_dest(struct kvm_vcpu *vcpu, struct kvm_lapic *source,
659 			   int short_hand, unsigned int dest, int dest_mode)
660 {
661 	struct kvm_lapic *target = vcpu->arch.apic;
662 	u32 mda = kvm_apic_mda(dest, source, target);
663 
664 	apic_debug("target %p, source %p, dest 0x%x, "
665 		   "dest_mode 0x%x, short_hand 0x%x\n",
666 		   target, source, dest, dest_mode, short_hand);
667 
668 	ASSERT(target);
669 	switch (short_hand) {
670 	case APIC_DEST_NOSHORT:
671 		if (dest_mode == APIC_DEST_PHYSICAL)
672 			return kvm_apic_match_physical_addr(target, mda);
673 		else
674 			return kvm_apic_match_logical_addr(target, mda);
675 	case APIC_DEST_SELF:
676 		return target == source;
677 	case APIC_DEST_ALLINC:
678 		return true;
679 	case APIC_DEST_ALLBUT:
680 		return target != source;
681 	default:
682 		apic_debug("kvm: apic: Bad dest shorthand value %x\n",
683 			   short_hand);
684 		return false;
685 	}
686 }
687 
688 bool kvm_irq_delivery_to_apic_fast(struct kvm *kvm, struct kvm_lapic *src,
689 		struct kvm_lapic_irq *irq, int *r, unsigned long *dest_map)
690 {
691 	struct kvm_apic_map *map;
692 	unsigned long bitmap = 1;
693 	struct kvm_lapic **dst;
694 	int i;
695 	bool ret, x2apic_ipi;
696 
697 	*r = -1;
698 
699 	if (irq->shorthand == APIC_DEST_SELF) {
700 		*r = kvm_apic_set_irq(src->vcpu, irq, dest_map);
701 		return true;
702 	}
703 
704 	if (irq->shorthand)
705 		return false;
706 
707 	x2apic_ipi = src && apic_x2apic_mode(src);
708 	if (irq->dest_id == (x2apic_ipi ? X2APIC_BROADCAST : APIC_BROADCAST))
709 		return false;
710 
711 	ret = true;
712 	rcu_read_lock();
713 	map = rcu_dereference(kvm->arch.apic_map);
714 
715 	if (!map) {
716 		ret = false;
717 		goto out;
718 	}
719 
720 	if (irq->dest_mode == APIC_DEST_PHYSICAL) {
721 		if (irq->dest_id >= ARRAY_SIZE(map->phys_map))
722 			goto out;
723 
724 		dst = &map->phys_map[irq->dest_id];
725 	} else {
726 		u16 cid;
727 
728 		if (!kvm_apic_logical_map_valid(map)) {
729 			ret = false;
730 			goto out;
731 		}
732 
733 		apic_logical_id(map, irq->dest_id, &cid, (u16 *)&bitmap);
734 
735 		if (cid >= ARRAY_SIZE(map->logical_map))
736 			goto out;
737 
738 		dst = map->logical_map[cid];
739 
740 		if (kvm_lowest_prio_delivery(irq)) {
741 			int l = -1;
742 			for_each_set_bit(i, &bitmap, 16) {
743 				if (!dst[i])
744 					continue;
745 				if (l < 0)
746 					l = i;
747 				else if (kvm_apic_compare_prio(dst[i]->vcpu, dst[l]->vcpu) < 0)
748 					l = i;
749 			}
750 
751 			bitmap = (l >= 0) ? 1 << l : 0;
752 		}
753 	}
754 
755 	for_each_set_bit(i, &bitmap, 16) {
756 		if (!dst[i])
757 			continue;
758 		if (*r < 0)
759 			*r = 0;
760 		*r += kvm_apic_set_irq(dst[i]->vcpu, irq, dest_map);
761 	}
762 out:
763 	rcu_read_unlock();
764 	return ret;
765 }
766 
767 /*
768  * Add a pending IRQ into lapic.
769  * Return 1 if successfully added and 0 if discarded.
770  */
771 static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode,
772 			     int vector, int level, int trig_mode,
773 			     unsigned long *dest_map)
774 {
775 	int result = 0;
776 	struct kvm_vcpu *vcpu = apic->vcpu;
777 
778 	trace_kvm_apic_accept_irq(vcpu->vcpu_id, delivery_mode,
779 				  trig_mode, vector);
780 	switch (delivery_mode) {
781 	case APIC_DM_LOWEST:
782 		vcpu->arch.apic_arb_prio++;
783 	case APIC_DM_FIXED:
784 		/* FIXME add logic for vcpu on reset */
785 		if (unlikely(!apic_enabled(apic)))
786 			break;
787 
788 		result = 1;
789 
790 		if (dest_map)
791 			__set_bit(vcpu->vcpu_id, dest_map);
792 
793 		if (kvm_x86_ops->deliver_posted_interrupt)
794 			kvm_x86_ops->deliver_posted_interrupt(vcpu, vector);
795 		else {
796 			apic_set_irr(vector, apic);
797 
798 			kvm_make_request(KVM_REQ_EVENT, vcpu);
799 			kvm_vcpu_kick(vcpu);
800 		}
801 		break;
802 
803 	case APIC_DM_REMRD:
804 		result = 1;
805 		vcpu->arch.pv.pv_unhalted = 1;
806 		kvm_make_request(KVM_REQ_EVENT, vcpu);
807 		kvm_vcpu_kick(vcpu);
808 		break;
809 
810 	case APIC_DM_SMI:
811 		result = 1;
812 		kvm_make_request(KVM_REQ_SMI, vcpu);
813 		kvm_vcpu_kick(vcpu);
814 		break;
815 
816 	case APIC_DM_NMI:
817 		result = 1;
818 		kvm_inject_nmi(vcpu);
819 		kvm_vcpu_kick(vcpu);
820 		break;
821 
822 	case APIC_DM_INIT:
823 		if (!trig_mode || level) {
824 			result = 1;
825 			/* assumes that there are only KVM_APIC_INIT/SIPI */
826 			apic->pending_events = (1UL << KVM_APIC_INIT);
827 			/* make sure pending_events is visible before sending
828 			 * the request */
829 			smp_wmb();
830 			kvm_make_request(KVM_REQ_EVENT, vcpu);
831 			kvm_vcpu_kick(vcpu);
832 		} else {
833 			apic_debug("Ignoring de-assert INIT to vcpu %d\n",
834 				   vcpu->vcpu_id);
835 		}
836 		break;
837 
838 	case APIC_DM_STARTUP:
839 		apic_debug("SIPI to vcpu %d vector 0x%02x\n",
840 			   vcpu->vcpu_id, vector);
841 		result = 1;
842 		apic->sipi_vector = vector;
843 		/* make sure sipi_vector is visible for the receiver */
844 		smp_wmb();
845 		set_bit(KVM_APIC_SIPI, &apic->pending_events);
846 		kvm_make_request(KVM_REQ_EVENT, vcpu);
847 		kvm_vcpu_kick(vcpu);
848 		break;
849 
850 	case APIC_DM_EXTINT:
851 		/*
852 		 * Should only be called by kvm_apic_local_deliver() with LVT0,
853 		 * before NMI watchdog was enabled. Already handled by
854 		 * kvm_apic_accept_pic_intr().
855 		 */
856 		break;
857 
858 	default:
859 		printk(KERN_ERR "TODO: unsupported delivery mode %x\n",
860 		       delivery_mode);
861 		break;
862 	}
863 	return result;
864 }
865 
866 int kvm_apic_compare_prio(struct kvm_vcpu *vcpu1, struct kvm_vcpu *vcpu2)
867 {
868 	return vcpu1->arch.apic_arb_prio - vcpu2->arch.apic_arb_prio;
869 }
870 
871 static void kvm_ioapic_send_eoi(struct kvm_lapic *apic, int vector)
872 {
873 	if (kvm_ioapic_handles_vector(apic->vcpu->kvm, vector)) {
874 		int trigger_mode;
875 		if (apic_test_vector(vector, apic->regs + APIC_TMR))
876 			trigger_mode = IOAPIC_LEVEL_TRIG;
877 		else
878 			trigger_mode = IOAPIC_EDGE_TRIG;
879 		kvm_ioapic_update_eoi(apic->vcpu, vector, trigger_mode);
880 	}
881 }
882 
883 static int apic_set_eoi(struct kvm_lapic *apic)
884 {
885 	int vector = apic_find_highest_isr(apic);
886 
887 	trace_kvm_eoi(apic, vector);
888 
889 	/*
890 	 * Not every write EOI will has corresponding ISR,
891 	 * one example is when Kernel check timer on setup_IO_APIC
892 	 */
893 	if (vector == -1)
894 		return vector;
895 
896 	apic_clear_isr(vector, apic);
897 	apic_update_ppr(apic);
898 
899 	kvm_ioapic_send_eoi(apic, vector);
900 	kvm_make_request(KVM_REQ_EVENT, apic->vcpu);
901 	return vector;
902 }
903 
904 /*
905  * this interface assumes a trap-like exit, which has already finished
906  * desired side effect including vISR and vPPR update.
907  */
908 void kvm_apic_set_eoi_accelerated(struct kvm_vcpu *vcpu, int vector)
909 {
910 	struct kvm_lapic *apic = vcpu->arch.apic;
911 
912 	trace_kvm_eoi(apic, vector);
913 
914 	kvm_ioapic_send_eoi(apic, vector);
915 	kvm_make_request(KVM_REQ_EVENT, apic->vcpu);
916 }
917 EXPORT_SYMBOL_GPL(kvm_apic_set_eoi_accelerated);
918 
919 static void apic_send_ipi(struct kvm_lapic *apic)
920 {
921 	u32 icr_low = kvm_apic_get_reg(apic, APIC_ICR);
922 	u32 icr_high = kvm_apic_get_reg(apic, APIC_ICR2);
923 	struct kvm_lapic_irq irq;
924 
925 	irq.vector = icr_low & APIC_VECTOR_MASK;
926 	irq.delivery_mode = icr_low & APIC_MODE_MASK;
927 	irq.dest_mode = icr_low & APIC_DEST_MASK;
928 	irq.level = (icr_low & APIC_INT_ASSERT) != 0;
929 	irq.trig_mode = icr_low & APIC_INT_LEVELTRIG;
930 	irq.shorthand = icr_low & APIC_SHORT_MASK;
931 	irq.msi_redir_hint = false;
932 	if (apic_x2apic_mode(apic))
933 		irq.dest_id = icr_high;
934 	else
935 		irq.dest_id = GET_APIC_DEST_FIELD(icr_high);
936 
937 	trace_kvm_apic_ipi(icr_low, irq.dest_id);
938 
939 	apic_debug("icr_high 0x%x, icr_low 0x%x, "
940 		   "short_hand 0x%x, dest 0x%x, trig_mode 0x%x, level 0x%x, "
941 		   "dest_mode 0x%x, delivery_mode 0x%x, vector 0x%x, "
942 		   "msi_redir_hint 0x%x\n",
943 		   icr_high, icr_low, irq.shorthand, irq.dest_id,
944 		   irq.trig_mode, irq.level, irq.dest_mode, irq.delivery_mode,
945 		   irq.vector, irq.msi_redir_hint);
946 
947 	kvm_irq_delivery_to_apic(apic->vcpu->kvm, apic, &irq, NULL);
948 }
949 
950 static u32 apic_get_tmcct(struct kvm_lapic *apic)
951 {
952 	ktime_t remaining;
953 	s64 ns;
954 	u32 tmcct;
955 
956 	ASSERT(apic != NULL);
957 
958 	/* if initial count is 0, current count should also be 0 */
959 	if (kvm_apic_get_reg(apic, APIC_TMICT) == 0 ||
960 		apic->lapic_timer.period == 0)
961 		return 0;
962 
963 	remaining = hrtimer_get_remaining(&apic->lapic_timer.timer);
964 	if (ktime_to_ns(remaining) < 0)
965 		remaining = ktime_set(0, 0);
966 
967 	ns = mod_64(ktime_to_ns(remaining), apic->lapic_timer.period);
968 	tmcct = div64_u64(ns,
969 			 (APIC_BUS_CYCLE_NS * apic->divide_count));
970 
971 	return tmcct;
972 }
973 
974 static void __report_tpr_access(struct kvm_lapic *apic, bool write)
975 {
976 	struct kvm_vcpu *vcpu = apic->vcpu;
977 	struct kvm_run *run = vcpu->run;
978 
979 	kvm_make_request(KVM_REQ_REPORT_TPR_ACCESS, vcpu);
980 	run->tpr_access.rip = kvm_rip_read(vcpu);
981 	run->tpr_access.is_write = write;
982 }
983 
984 static inline void report_tpr_access(struct kvm_lapic *apic, bool write)
985 {
986 	if (apic->vcpu->arch.tpr_access_reporting)
987 		__report_tpr_access(apic, write);
988 }
989 
990 static u32 __apic_read(struct kvm_lapic *apic, unsigned int offset)
991 {
992 	u32 val = 0;
993 
994 	if (offset >= LAPIC_MMIO_LENGTH)
995 		return 0;
996 
997 	switch (offset) {
998 	case APIC_ID:
999 		if (apic_x2apic_mode(apic))
1000 			val = kvm_apic_id(apic);
1001 		else
1002 			val = kvm_apic_id(apic) << 24;
1003 		break;
1004 	case APIC_ARBPRI:
1005 		apic_debug("Access APIC ARBPRI register which is for P6\n");
1006 		break;
1007 
1008 	case APIC_TMCCT:	/* Timer CCR */
1009 		if (apic_lvtt_tscdeadline(apic))
1010 			return 0;
1011 
1012 		val = apic_get_tmcct(apic);
1013 		break;
1014 	case APIC_PROCPRI:
1015 		apic_update_ppr(apic);
1016 		val = kvm_apic_get_reg(apic, offset);
1017 		break;
1018 	case APIC_TASKPRI:
1019 		report_tpr_access(apic, false);
1020 		/* fall thru */
1021 	default:
1022 		val = kvm_apic_get_reg(apic, offset);
1023 		break;
1024 	}
1025 
1026 	return val;
1027 }
1028 
1029 static inline struct kvm_lapic *to_lapic(struct kvm_io_device *dev)
1030 {
1031 	return container_of(dev, struct kvm_lapic, dev);
1032 }
1033 
1034 static int apic_reg_read(struct kvm_lapic *apic, u32 offset, int len,
1035 		void *data)
1036 {
1037 	unsigned char alignment = offset & 0xf;
1038 	u32 result;
1039 	/* this bitmask has a bit cleared for each reserved register */
1040 	static const u64 rmask = 0x43ff01ffffffe70cULL;
1041 
1042 	if ((alignment + len) > 4) {
1043 		apic_debug("KVM_APIC_READ: alignment error %x %d\n",
1044 			   offset, len);
1045 		return 1;
1046 	}
1047 
1048 	if (offset > 0x3f0 || !(rmask & (1ULL << (offset >> 4)))) {
1049 		apic_debug("KVM_APIC_READ: read reserved register %x\n",
1050 			   offset);
1051 		return 1;
1052 	}
1053 
1054 	result = __apic_read(apic, offset & ~0xf);
1055 
1056 	trace_kvm_apic_read(offset, result);
1057 
1058 	switch (len) {
1059 	case 1:
1060 	case 2:
1061 	case 4:
1062 		memcpy(data, (char *)&result + alignment, len);
1063 		break;
1064 	default:
1065 		printk(KERN_ERR "Local APIC read with len = %x, "
1066 		       "should be 1,2, or 4 instead\n", len);
1067 		break;
1068 	}
1069 	return 0;
1070 }
1071 
1072 static int apic_mmio_in_range(struct kvm_lapic *apic, gpa_t addr)
1073 {
1074 	return kvm_apic_hw_enabled(apic) &&
1075 	    addr >= apic->base_address &&
1076 	    addr < apic->base_address + LAPIC_MMIO_LENGTH;
1077 }
1078 
1079 static int apic_mmio_read(struct kvm_vcpu *vcpu, struct kvm_io_device *this,
1080 			   gpa_t address, int len, void *data)
1081 {
1082 	struct kvm_lapic *apic = to_lapic(this);
1083 	u32 offset = address - apic->base_address;
1084 
1085 	if (!apic_mmio_in_range(apic, address))
1086 		return -EOPNOTSUPP;
1087 
1088 	apic_reg_read(apic, offset, len, data);
1089 
1090 	return 0;
1091 }
1092 
1093 static void update_divide_count(struct kvm_lapic *apic)
1094 {
1095 	u32 tmp1, tmp2, tdcr;
1096 
1097 	tdcr = kvm_apic_get_reg(apic, APIC_TDCR);
1098 	tmp1 = tdcr & 0xf;
1099 	tmp2 = ((tmp1 & 0x3) | ((tmp1 & 0x8) >> 1)) + 1;
1100 	apic->divide_count = 0x1 << (tmp2 & 0x7);
1101 
1102 	apic_debug("timer divide count is 0x%x\n",
1103 				   apic->divide_count);
1104 }
1105 
1106 static void apic_update_lvtt(struct kvm_lapic *apic)
1107 {
1108 	u32 timer_mode = kvm_apic_get_reg(apic, APIC_LVTT) &
1109 			apic->lapic_timer.timer_mode_mask;
1110 
1111 	if (apic->lapic_timer.timer_mode != timer_mode) {
1112 		apic->lapic_timer.timer_mode = timer_mode;
1113 		hrtimer_cancel(&apic->lapic_timer.timer);
1114 	}
1115 }
1116 
1117 static void apic_timer_expired(struct kvm_lapic *apic)
1118 {
1119 	struct kvm_vcpu *vcpu = apic->vcpu;
1120 	wait_queue_head_t *q = &vcpu->wq;
1121 	struct kvm_timer *ktimer = &apic->lapic_timer;
1122 
1123 	if (atomic_read(&apic->lapic_timer.pending))
1124 		return;
1125 
1126 	atomic_inc(&apic->lapic_timer.pending);
1127 	kvm_set_pending_timer(vcpu);
1128 
1129 	if (waitqueue_active(q))
1130 		wake_up_interruptible(q);
1131 
1132 	if (apic_lvtt_tscdeadline(apic))
1133 		ktimer->expired_tscdeadline = ktimer->tscdeadline;
1134 }
1135 
1136 /*
1137  * On APICv, this test will cause a busy wait
1138  * during a higher-priority task.
1139  */
1140 
1141 static bool lapic_timer_int_injected(struct kvm_vcpu *vcpu)
1142 {
1143 	struct kvm_lapic *apic = vcpu->arch.apic;
1144 	u32 reg = kvm_apic_get_reg(apic, APIC_LVTT);
1145 
1146 	if (kvm_apic_hw_enabled(apic)) {
1147 		int vec = reg & APIC_VECTOR_MASK;
1148 		void *bitmap = apic->regs + APIC_ISR;
1149 
1150 		if (kvm_x86_ops->deliver_posted_interrupt)
1151 			bitmap = apic->regs + APIC_IRR;
1152 
1153 		if (apic_test_vector(vec, bitmap))
1154 			return true;
1155 	}
1156 	return false;
1157 }
1158 
1159 void wait_lapic_expire(struct kvm_vcpu *vcpu)
1160 {
1161 	struct kvm_lapic *apic = vcpu->arch.apic;
1162 	u64 guest_tsc, tsc_deadline;
1163 
1164 	if (!kvm_vcpu_has_lapic(vcpu))
1165 		return;
1166 
1167 	if (apic->lapic_timer.expired_tscdeadline == 0)
1168 		return;
1169 
1170 	if (!lapic_timer_int_injected(vcpu))
1171 		return;
1172 
1173 	tsc_deadline = apic->lapic_timer.expired_tscdeadline;
1174 	apic->lapic_timer.expired_tscdeadline = 0;
1175 	guest_tsc = kvm_x86_ops->read_l1_tsc(vcpu, native_read_tsc());
1176 	trace_kvm_wait_lapic_expire(vcpu->vcpu_id, guest_tsc - tsc_deadline);
1177 
1178 	/* __delay is delay_tsc whenever the hardware has TSC, thus always.  */
1179 	if (guest_tsc < tsc_deadline)
1180 		__delay(tsc_deadline - guest_tsc);
1181 }
1182 
1183 static void start_apic_timer(struct kvm_lapic *apic)
1184 {
1185 	ktime_t now;
1186 
1187 	atomic_set(&apic->lapic_timer.pending, 0);
1188 
1189 	if (apic_lvtt_period(apic) || apic_lvtt_oneshot(apic)) {
1190 		/* lapic timer in oneshot or periodic mode */
1191 		now = apic->lapic_timer.timer.base->get_time();
1192 		apic->lapic_timer.period = (u64)kvm_apic_get_reg(apic, APIC_TMICT)
1193 			    * APIC_BUS_CYCLE_NS * apic->divide_count;
1194 
1195 		if (!apic->lapic_timer.period)
1196 			return;
1197 		/*
1198 		 * Do not allow the guest to program periodic timers with small
1199 		 * interval, since the hrtimers are not throttled by the host
1200 		 * scheduler.
1201 		 */
1202 		if (apic_lvtt_period(apic)) {
1203 			s64 min_period = min_timer_period_us * 1000LL;
1204 
1205 			if (apic->lapic_timer.period < min_period) {
1206 				pr_info_ratelimited(
1207 				    "kvm: vcpu %i: requested %lld ns "
1208 				    "lapic timer period limited to %lld ns\n",
1209 				    apic->vcpu->vcpu_id,
1210 				    apic->lapic_timer.period, min_period);
1211 				apic->lapic_timer.period = min_period;
1212 			}
1213 		}
1214 
1215 		hrtimer_start(&apic->lapic_timer.timer,
1216 			      ktime_add_ns(now, apic->lapic_timer.period),
1217 			      HRTIMER_MODE_ABS);
1218 
1219 		apic_debug("%s: bus cycle is %" PRId64 "ns, now 0x%016"
1220 			   PRIx64 ", "
1221 			   "timer initial count 0x%x, period %lldns, "
1222 			   "expire @ 0x%016" PRIx64 ".\n", __func__,
1223 			   APIC_BUS_CYCLE_NS, ktime_to_ns(now),
1224 			   kvm_apic_get_reg(apic, APIC_TMICT),
1225 			   apic->lapic_timer.period,
1226 			   ktime_to_ns(ktime_add_ns(now,
1227 					apic->lapic_timer.period)));
1228 	} else if (apic_lvtt_tscdeadline(apic)) {
1229 		/* lapic timer in tsc deadline mode */
1230 		u64 guest_tsc, tscdeadline = apic->lapic_timer.tscdeadline;
1231 		u64 ns = 0;
1232 		ktime_t expire;
1233 		struct kvm_vcpu *vcpu = apic->vcpu;
1234 		unsigned long this_tsc_khz = vcpu->arch.virtual_tsc_khz;
1235 		unsigned long flags;
1236 
1237 		if (unlikely(!tscdeadline || !this_tsc_khz))
1238 			return;
1239 
1240 		local_irq_save(flags);
1241 
1242 		now = apic->lapic_timer.timer.base->get_time();
1243 		guest_tsc = kvm_x86_ops->read_l1_tsc(vcpu, native_read_tsc());
1244 		if (likely(tscdeadline > guest_tsc)) {
1245 			ns = (tscdeadline - guest_tsc) * 1000000ULL;
1246 			do_div(ns, this_tsc_khz);
1247 			expire = ktime_add_ns(now, ns);
1248 			expire = ktime_sub_ns(expire, lapic_timer_advance_ns);
1249 			hrtimer_start(&apic->lapic_timer.timer,
1250 				      expire, HRTIMER_MODE_ABS);
1251 		} else
1252 			apic_timer_expired(apic);
1253 
1254 		local_irq_restore(flags);
1255 	}
1256 }
1257 
1258 static void apic_manage_nmi_watchdog(struct kvm_lapic *apic, u32 lvt0_val)
1259 {
1260 	int nmi_wd_enabled = apic_lvt_nmi_mode(kvm_apic_get_reg(apic, APIC_LVT0));
1261 
1262 	if (apic_lvt_nmi_mode(lvt0_val)) {
1263 		if (!nmi_wd_enabled) {
1264 			apic_debug("Receive NMI setting on APIC_LVT0 "
1265 				   "for cpu %d\n", apic->vcpu->vcpu_id);
1266 			apic->vcpu->kvm->arch.vapics_in_nmi_mode++;
1267 		}
1268 	} else if (nmi_wd_enabled)
1269 		apic->vcpu->kvm->arch.vapics_in_nmi_mode--;
1270 }
1271 
1272 static int apic_reg_write(struct kvm_lapic *apic, u32 reg, u32 val)
1273 {
1274 	int ret = 0;
1275 
1276 	trace_kvm_apic_write(reg, val);
1277 
1278 	switch (reg) {
1279 	case APIC_ID:		/* Local APIC ID */
1280 		if (!apic_x2apic_mode(apic))
1281 			kvm_apic_set_id(apic, val >> 24);
1282 		else
1283 			ret = 1;
1284 		break;
1285 
1286 	case APIC_TASKPRI:
1287 		report_tpr_access(apic, true);
1288 		apic_set_tpr(apic, val & 0xff);
1289 		break;
1290 
1291 	case APIC_EOI:
1292 		apic_set_eoi(apic);
1293 		break;
1294 
1295 	case APIC_LDR:
1296 		if (!apic_x2apic_mode(apic))
1297 			kvm_apic_set_ldr(apic, val & APIC_LDR_MASK);
1298 		else
1299 			ret = 1;
1300 		break;
1301 
1302 	case APIC_DFR:
1303 		if (!apic_x2apic_mode(apic)) {
1304 			apic_set_reg(apic, APIC_DFR, val | 0x0FFFFFFF);
1305 			recalculate_apic_map(apic->vcpu->kvm);
1306 		} else
1307 			ret = 1;
1308 		break;
1309 
1310 	case APIC_SPIV: {
1311 		u32 mask = 0x3ff;
1312 		if (kvm_apic_get_reg(apic, APIC_LVR) & APIC_LVR_DIRECTED_EOI)
1313 			mask |= APIC_SPIV_DIRECTED_EOI;
1314 		apic_set_spiv(apic, val & mask);
1315 		if (!(val & APIC_SPIV_APIC_ENABLED)) {
1316 			int i;
1317 			u32 lvt_val;
1318 
1319 			for (i = 0; i < APIC_LVT_NUM; i++) {
1320 				lvt_val = kvm_apic_get_reg(apic,
1321 						       APIC_LVTT + 0x10 * i);
1322 				apic_set_reg(apic, APIC_LVTT + 0x10 * i,
1323 					     lvt_val | APIC_LVT_MASKED);
1324 			}
1325 			apic_update_lvtt(apic);
1326 			atomic_set(&apic->lapic_timer.pending, 0);
1327 
1328 		}
1329 		break;
1330 	}
1331 	case APIC_ICR:
1332 		/* No delay here, so we always clear the pending bit */
1333 		apic_set_reg(apic, APIC_ICR, val & ~(1 << 12));
1334 		apic_send_ipi(apic);
1335 		break;
1336 
1337 	case APIC_ICR2:
1338 		if (!apic_x2apic_mode(apic))
1339 			val &= 0xff000000;
1340 		apic_set_reg(apic, APIC_ICR2, val);
1341 		break;
1342 
1343 	case APIC_LVT0:
1344 		apic_manage_nmi_watchdog(apic, val);
1345 	case APIC_LVTTHMR:
1346 	case APIC_LVTPC:
1347 	case APIC_LVT1:
1348 	case APIC_LVTERR:
1349 		/* TODO: Check vector */
1350 		if (!kvm_apic_sw_enabled(apic))
1351 			val |= APIC_LVT_MASKED;
1352 
1353 		val &= apic_lvt_mask[(reg - APIC_LVTT) >> 4];
1354 		apic_set_reg(apic, reg, val);
1355 
1356 		break;
1357 
1358 	case APIC_LVTT:
1359 		if (!kvm_apic_sw_enabled(apic))
1360 			val |= APIC_LVT_MASKED;
1361 		val &= (apic_lvt_mask[0] | apic->lapic_timer.timer_mode_mask);
1362 		apic_set_reg(apic, APIC_LVTT, val);
1363 		apic_update_lvtt(apic);
1364 		break;
1365 
1366 	case APIC_TMICT:
1367 		if (apic_lvtt_tscdeadline(apic))
1368 			break;
1369 
1370 		hrtimer_cancel(&apic->lapic_timer.timer);
1371 		apic_set_reg(apic, APIC_TMICT, val);
1372 		start_apic_timer(apic);
1373 		break;
1374 
1375 	case APIC_TDCR:
1376 		if (val & 4)
1377 			apic_debug("KVM_WRITE:TDCR %x\n", val);
1378 		apic_set_reg(apic, APIC_TDCR, val);
1379 		update_divide_count(apic);
1380 		break;
1381 
1382 	case APIC_ESR:
1383 		if (apic_x2apic_mode(apic) && val != 0) {
1384 			apic_debug("KVM_WRITE:ESR not zero %x\n", val);
1385 			ret = 1;
1386 		}
1387 		break;
1388 
1389 	case APIC_SELF_IPI:
1390 		if (apic_x2apic_mode(apic)) {
1391 			apic_reg_write(apic, APIC_ICR, 0x40000 | (val & 0xff));
1392 		} else
1393 			ret = 1;
1394 		break;
1395 	default:
1396 		ret = 1;
1397 		break;
1398 	}
1399 	if (ret)
1400 		apic_debug("Local APIC Write to read-only register %x\n", reg);
1401 	return ret;
1402 }
1403 
1404 static int apic_mmio_write(struct kvm_vcpu *vcpu, struct kvm_io_device *this,
1405 			    gpa_t address, int len, const void *data)
1406 {
1407 	struct kvm_lapic *apic = to_lapic(this);
1408 	unsigned int offset = address - apic->base_address;
1409 	u32 val;
1410 
1411 	if (!apic_mmio_in_range(apic, address))
1412 		return -EOPNOTSUPP;
1413 
1414 	/*
1415 	 * APIC register must be aligned on 128-bits boundary.
1416 	 * 32/64/128 bits registers must be accessed thru 32 bits.
1417 	 * Refer SDM 8.4.1
1418 	 */
1419 	if (len != 4 || (offset & 0xf)) {
1420 		/* Don't shout loud, $infamous_os would cause only noise. */
1421 		apic_debug("apic write: bad size=%d %lx\n", len, (long)address);
1422 		return 0;
1423 	}
1424 
1425 	val = *(u32*)data;
1426 
1427 	/* too common printing */
1428 	if (offset != APIC_EOI)
1429 		apic_debug("%s: offset 0x%x with length 0x%x, and value is "
1430 			   "0x%x\n", __func__, offset, len, val);
1431 
1432 	apic_reg_write(apic, offset & 0xff0, val);
1433 
1434 	return 0;
1435 }
1436 
1437 void kvm_lapic_set_eoi(struct kvm_vcpu *vcpu)
1438 {
1439 	if (kvm_vcpu_has_lapic(vcpu))
1440 		apic_reg_write(vcpu->arch.apic, APIC_EOI, 0);
1441 }
1442 EXPORT_SYMBOL_GPL(kvm_lapic_set_eoi);
1443 
1444 /* emulate APIC access in a trap manner */
1445 void kvm_apic_write_nodecode(struct kvm_vcpu *vcpu, u32 offset)
1446 {
1447 	u32 val = 0;
1448 
1449 	/* hw has done the conditional check and inst decode */
1450 	offset &= 0xff0;
1451 
1452 	apic_reg_read(vcpu->arch.apic, offset, 4, &val);
1453 
1454 	/* TODO: optimize to just emulate side effect w/o one more write */
1455 	apic_reg_write(vcpu->arch.apic, offset, val);
1456 }
1457 EXPORT_SYMBOL_GPL(kvm_apic_write_nodecode);
1458 
1459 void kvm_free_lapic(struct kvm_vcpu *vcpu)
1460 {
1461 	struct kvm_lapic *apic = vcpu->arch.apic;
1462 
1463 	if (!vcpu->arch.apic)
1464 		return;
1465 
1466 	hrtimer_cancel(&apic->lapic_timer.timer);
1467 
1468 	if (!(vcpu->arch.apic_base & MSR_IA32_APICBASE_ENABLE))
1469 		static_key_slow_dec_deferred(&apic_hw_disabled);
1470 
1471 	if (!apic->sw_enabled)
1472 		static_key_slow_dec_deferred(&apic_sw_disabled);
1473 
1474 	if (apic->regs)
1475 		free_page((unsigned long)apic->regs);
1476 
1477 	kfree(apic);
1478 }
1479 
1480 /*
1481  *----------------------------------------------------------------------
1482  * LAPIC interface
1483  *----------------------------------------------------------------------
1484  */
1485 
1486 u64 kvm_get_lapic_tscdeadline_msr(struct kvm_vcpu *vcpu)
1487 {
1488 	struct kvm_lapic *apic = vcpu->arch.apic;
1489 
1490 	if (!kvm_vcpu_has_lapic(vcpu) || apic_lvtt_oneshot(apic) ||
1491 			apic_lvtt_period(apic))
1492 		return 0;
1493 
1494 	return apic->lapic_timer.tscdeadline;
1495 }
1496 
1497 void kvm_set_lapic_tscdeadline_msr(struct kvm_vcpu *vcpu, u64 data)
1498 {
1499 	struct kvm_lapic *apic = vcpu->arch.apic;
1500 
1501 	if (!kvm_vcpu_has_lapic(vcpu) || apic_lvtt_oneshot(apic) ||
1502 			apic_lvtt_period(apic))
1503 		return;
1504 
1505 	hrtimer_cancel(&apic->lapic_timer.timer);
1506 	apic->lapic_timer.tscdeadline = data;
1507 	start_apic_timer(apic);
1508 }
1509 
1510 void kvm_lapic_set_tpr(struct kvm_vcpu *vcpu, unsigned long cr8)
1511 {
1512 	struct kvm_lapic *apic = vcpu->arch.apic;
1513 
1514 	if (!kvm_vcpu_has_lapic(vcpu))
1515 		return;
1516 
1517 	apic_set_tpr(apic, ((cr8 & 0x0f) << 4)
1518 		     | (kvm_apic_get_reg(apic, APIC_TASKPRI) & 4));
1519 }
1520 
1521 u64 kvm_lapic_get_cr8(struct kvm_vcpu *vcpu)
1522 {
1523 	u64 tpr;
1524 
1525 	if (!kvm_vcpu_has_lapic(vcpu))
1526 		return 0;
1527 
1528 	tpr = (u64) kvm_apic_get_reg(vcpu->arch.apic, APIC_TASKPRI);
1529 
1530 	return (tpr & 0xf0) >> 4;
1531 }
1532 
1533 void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value)
1534 {
1535 	u64 old_value = vcpu->arch.apic_base;
1536 	struct kvm_lapic *apic = vcpu->arch.apic;
1537 
1538 	if (!apic) {
1539 		value |= MSR_IA32_APICBASE_BSP;
1540 		vcpu->arch.apic_base = value;
1541 		return;
1542 	}
1543 
1544 	vcpu->arch.apic_base = value;
1545 
1546 	/* update jump label if enable bit changes */
1547 	if ((old_value ^ value) & MSR_IA32_APICBASE_ENABLE) {
1548 		if (value & MSR_IA32_APICBASE_ENABLE)
1549 			static_key_slow_dec_deferred(&apic_hw_disabled);
1550 		else
1551 			static_key_slow_inc(&apic_hw_disabled.key);
1552 		recalculate_apic_map(vcpu->kvm);
1553 	}
1554 
1555 	if ((old_value ^ value) & X2APIC_ENABLE) {
1556 		if (value & X2APIC_ENABLE) {
1557 			kvm_apic_set_x2apic_id(apic, vcpu->vcpu_id);
1558 			kvm_x86_ops->set_virtual_x2apic_mode(vcpu, true);
1559 		} else
1560 			kvm_x86_ops->set_virtual_x2apic_mode(vcpu, false);
1561 	}
1562 
1563 	apic->base_address = apic->vcpu->arch.apic_base &
1564 			     MSR_IA32_APICBASE_BASE;
1565 
1566 	if ((value & MSR_IA32_APICBASE_ENABLE) &&
1567 	     apic->base_address != APIC_DEFAULT_PHYS_BASE)
1568 		pr_warn_once("APIC base relocation is unsupported by KVM");
1569 
1570 	/* with FSB delivery interrupt, we can restart APIC functionality */
1571 	apic_debug("apic base msr is 0x%016" PRIx64 ", and base address is "
1572 		   "0x%lx.\n", apic->vcpu->arch.apic_base, apic->base_address);
1573 
1574 }
1575 
1576 void kvm_lapic_reset(struct kvm_vcpu *vcpu, bool init_event)
1577 {
1578 	struct kvm_lapic *apic;
1579 	int i;
1580 
1581 	apic_debug("%s\n", __func__);
1582 
1583 	ASSERT(vcpu);
1584 	apic = vcpu->arch.apic;
1585 	ASSERT(apic != NULL);
1586 
1587 	/* Stop the timer in case it's a reset to an active apic */
1588 	hrtimer_cancel(&apic->lapic_timer.timer);
1589 
1590 	if (!init_event)
1591 		kvm_apic_set_id(apic, vcpu->vcpu_id);
1592 	kvm_apic_set_version(apic->vcpu);
1593 
1594 	for (i = 0; i < APIC_LVT_NUM; i++)
1595 		apic_set_reg(apic, APIC_LVTT + 0x10 * i, APIC_LVT_MASKED);
1596 	apic_update_lvtt(apic);
1597 	if (!(vcpu->kvm->arch.disabled_quirks & KVM_QUIRK_LINT0_REENABLED))
1598 		apic_set_reg(apic, APIC_LVT0,
1599 			     SET_APIC_DELIVERY_MODE(0, APIC_MODE_EXTINT));
1600 
1601 	apic_set_reg(apic, APIC_DFR, 0xffffffffU);
1602 	apic_set_spiv(apic, 0xff);
1603 	apic_set_reg(apic, APIC_TASKPRI, 0);
1604 	if (!apic_x2apic_mode(apic))
1605 		kvm_apic_set_ldr(apic, 0);
1606 	apic_set_reg(apic, APIC_ESR, 0);
1607 	apic_set_reg(apic, APIC_ICR, 0);
1608 	apic_set_reg(apic, APIC_ICR2, 0);
1609 	apic_set_reg(apic, APIC_TDCR, 0);
1610 	apic_set_reg(apic, APIC_TMICT, 0);
1611 	for (i = 0; i < 8; i++) {
1612 		apic_set_reg(apic, APIC_IRR + 0x10 * i, 0);
1613 		apic_set_reg(apic, APIC_ISR + 0x10 * i, 0);
1614 		apic_set_reg(apic, APIC_TMR + 0x10 * i, 0);
1615 	}
1616 	apic->irr_pending = kvm_apic_vid_enabled(vcpu->kvm);
1617 	apic->isr_count = kvm_x86_ops->hwapic_isr_update ? 1 : 0;
1618 	apic->highest_isr_cache = -1;
1619 	update_divide_count(apic);
1620 	atomic_set(&apic->lapic_timer.pending, 0);
1621 	if (kvm_vcpu_is_bsp(vcpu))
1622 		kvm_lapic_set_base(vcpu,
1623 				vcpu->arch.apic_base | MSR_IA32_APICBASE_BSP);
1624 	vcpu->arch.pv_eoi.msr_val = 0;
1625 	apic_update_ppr(apic);
1626 
1627 	vcpu->arch.apic_arb_prio = 0;
1628 	vcpu->arch.apic_attention = 0;
1629 
1630 	apic_debug("%s: vcpu=%p, id=%d, base_msr="
1631 		   "0x%016" PRIx64 ", base_address=0x%0lx.\n", __func__,
1632 		   vcpu, kvm_apic_id(apic),
1633 		   vcpu->arch.apic_base, apic->base_address);
1634 }
1635 
1636 /*
1637  *----------------------------------------------------------------------
1638  * timer interface
1639  *----------------------------------------------------------------------
1640  */
1641 
1642 static bool lapic_is_periodic(struct kvm_lapic *apic)
1643 {
1644 	return apic_lvtt_period(apic);
1645 }
1646 
1647 int apic_has_pending_timer(struct kvm_vcpu *vcpu)
1648 {
1649 	struct kvm_lapic *apic = vcpu->arch.apic;
1650 
1651 	if (kvm_vcpu_has_lapic(vcpu) && apic_enabled(apic) &&
1652 			apic_lvt_enabled(apic, APIC_LVTT))
1653 		return atomic_read(&apic->lapic_timer.pending);
1654 
1655 	return 0;
1656 }
1657 
1658 int kvm_apic_local_deliver(struct kvm_lapic *apic, int lvt_type)
1659 {
1660 	u32 reg = kvm_apic_get_reg(apic, lvt_type);
1661 	int vector, mode, trig_mode;
1662 
1663 	if (kvm_apic_hw_enabled(apic) && !(reg & APIC_LVT_MASKED)) {
1664 		vector = reg & APIC_VECTOR_MASK;
1665 		mode = reg & APIC_MODE_MASK;
1666 		trig_mode = reg & APIC_LVT_LEVEL_TRIGGER;
1667 		return __apic_accept_irq(apic, mode, vector, 1, trig_mode,
1668 					NULL);
1669 	}
1670 	return 0;
1671 }
1672 
1673 void kvm_apic_nmi_wd_deliver(struct kvm_vcpu *vcpu)
1674 {
1675 	struct kvm_lapic *apic = vcpu->arch.apic;
1676 
1677 	if (apic)
1678 		kvm_apic_local_deliver(apic, APIC_LVT0);
1679 }
1680 
1681 static const struct kvm_io_device_ops apic_mmio_ops = {
1682 	.read     = apic_mmio_read,
1683 	.write    = apic_mmio_write,
1684 };
1685 
1686 static enum hrtimer_restart apic_timer_fn(struct hrtimer *data)
1687 {
1688 	struct kvm_timer *ktimer = container_of(data, struct kvm_timer, timer);
1689 	struct kvm_lapic *apic = container_of(ktimer, struct kvm_lapic, lapic_timer);
1690 
1691 	apic_timer_expired(apic);
1692 
1693 	if (lapic_is_periodic(apic)) {
1694 		hrtimer_add_expires_ns(&ktimer->timer, ktimer->period);
1695 		return HRTIMER_RESTART;
1696 	} else
1697 		return HRTIMER_NORESTART;
1698 }
1699 
1700 int kvm_create_lapic(struct kvm_vcpu *vcpu)
1701 {
1702 	struct kvm_lapic *apic;
1703 
1704 	ASSERT(vcpu != NULL);
1705 	apic_debug("apic_init %d\n", vcpu->vcpu_id);
1706 
1707 	apic = kzalloc(sizeof(*apic), GFP_KERNEL);
1708 	if (!apic)
1709 		goto nomem;
1710 
1711 	vcpu->arch.apic = apic;
1712 
1713 	apic->regs = (void *)get_zeroed_page(GFP_KERNEL);
1714 	if (!apic->regs) {
1715 		printk(KERN_ERR "malloc apic regs error for vcpu %x\n",
1716 		       vcpu->vcpu_id);
1717 		goto nomem_free_apic;
1718 	}
1719 	apic->vcpu = vcpu;
1720 
1721 	hrtimer_init(&apic->lapic_timer.timer, CLOCK_MONOTONIC,
1722 		     HRTIMER_MODE_ABS);
1723 	apic->lapic_timer.timer.function = apic_timer_fn;
1724 
1725 	/*
1726 	 * APIC is created enabled. This will prevent kvm_lapic_set_base from
1727 	 * thinking that APIC satet has changed.
1728 	 */
1729 	vcpu->arch.apic_base = MSR_IA32_APICBASE_ENABLE;
1730 	kvm_lapic_set_base(vcpu,
1731 			APIC_DEFAULT_PHYS_BASE | MSR_IA32_APICBASE_ENABLE);
1732 
1733 	static_key_slow_inc(&apic_sw_disabled.key); /* sw disabled at reset */
1734 	kvm_lapic_reset(vcpu, false);
1735 	kvm_iodevice_init(&apic->dev, &apic_mmio_ops);
1736 
1737 	return 0;
1738 nomem_free_apic:
1739 	kfree(apic);
1740 nomem:
1741 	return -ENOMEM;
1742 }
1743 
1744 int kvm_apic_has_interrupt(struct kvm_vcpu *vcpu)
1745 {
1746 	struct kvm_lapic *apic = vcpu->arch.apic;
1747 	int highest_irr;
1748 
1749 	if (!kvm_vcpu_has_lapic(vcpu) || !apic_enabled(apic))
1750 		return -1;
1751 
1752 	apic_update_ppr(apic);
1753 	highest_irr = apic_find_highest_irr(apic);
1754 	if ((highest_irr == -1) ||
1755 	    ((highest_irr & 0xF0) <= kvm_apic_get_reg(apic, APIC_PROCPRI)))
1756 		return -1;
1757 	return highest_irr;
1758 }
1759 
1760 int kvm_apic_accept_pic_intr(struct kvm_vcpu *vcpu)
1761 {
1762 	u32 lvt0 = kvm_apic_get_reg(vcpu->arch.apic, APIC_LVT0);
1763 	int r = 0;
1764 
1765 	if (!kvm_apic_hw_enabled(vcpu->arch.apic))
1766 		r = 1;
1767 	if ((lvt0 & APIC_LVT_MASKED) == 0 &&
1768 	    GET_APIC_DELIVERY_MODE(lvt0) == APIC_MODE_EXTINT)
1769 		r = 1;
1770 	return r;
1771 }
1772 
1773 void kvm_inject_apic_timer_irqs(struct kvm_vcpu *vcpu)
1774 {
1775 	struct kvm_lapic *apic = vcpu->arch.apic;
1776 
1777 	if (!kvm_vcpu_has_lapic(vcpu))
1778 		return;
1779 
1780 	if (atomic_read(&apic->lapic_timer.pending) > 0) {
1781 		kvm_apic_local_deliver(apic, APIC_LVTT);
1782 		if (apic_lvtt_tscdeadline(apic))
1783 			apic->lapic_timer.tscdeadline = 0;
1784 		atomic_set(&apic->lapic_timer.pending, 0);
1785 	}
1786 }
1787 
1788 int kvm_get_apic_interrupt(struct kvm_vcpu *vcpu)
1789 {
1790 	int vector = kvm_apic_has_interrupt(vcpu);
1791 	struct kvm_lapic *apic = vcpu->arch.apic;
1792 
1793 	if (vector == -1)
1794 		return -1;
1795 
1796 	/*
1797 	 * We get here even with APIC virtualization enabled, if doing
1798 	 * nested virtualization and L1 runs with the "acknowledge interrupt
1799 	 * on exit" mode.  Then we cannot inject the interrupt via RVI,
1800 	 * because the process would deliver it through the IDT.
1801 	 */
1802 
1803 	apic_set_isr(vector, apic);
1804 	apic_update_ppr(apic);
1805 	apic_clear_irr(vector, apic);
1806 	return vector;
1807 }
1808 
1809 void kvm_apic_post_state_restore(struct kvm_vcpu *vcpu,
1810 		struct kvm_lapic_state *s)
1811 {
1812 	struct kvm_lapic *apic = vcpu->arch.apic;
1813 
1814 	kvm_lapic_set_base(vcpu, vcpu->arch.apic_base);
1815 	/* set SPIV separately to get count of SW disabled APICs right */
1816 	apic_set_spiv(apic, *((u32 *)(s->regs + APIC_SPIV)));
1817 	memcpy(vcpu->arch.apic->regs, s->regs, sizeof *s);
1818 	/* call kvm_apic_set_id() to put apic into apic_map */
1819 	kvm_apic_set_id(apic, kvm_apic_id(apic));
1820 	kvm_apic_set_version(vcpu);
1821 
1822 	apic_update_ppr(apic);
1823 	hrtimer_cancel(&apic->lapic_timer.timer);
1824 	apic_update_lvtt(apic);
1825 	update_divide_count(apic);
1826 	start_apic_timer(apic);
1827 	apic->irr_pending = true;
1828 	apic->isr_count = kvm_x86_ops->hwapic_isr_update ?
1829 				1 : count_vectors(apic->regs + APIC_ISR);
1830 	apic->highest_isr_cache = -1;
1831 	if (kvm_x86_ops->hwapic_irr_update)
1832 		kvm_x86_ops->hwapic_irr_update(vcpu,
1833 				apic_find_highest_irr(apic));
1834 	if (unlikely(kvm_x86_ops->hwapic_isr_update))
1835 		kvm_x86_ops->hwapic_isr_update(vcpu->kvm,
1836 				apic_find_highest_isr(apic));
1837 	kvm_make_request(KVM_REQ_EVENT, vcpu);
1838 	kvm_rtc_eoi_tracking_restore_one(vcpu);
1839 }
1840 
1841 void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
1842 {
1843 	struct hrtimer *timer;
1844 
1845 	if (!kvm_vcpu_has_lapic(vcpu))
1846 		return;
1847 
1848 	timer = &vcpu->arch.apic->lapic_timer.timer;
1849 	if (hrtimer_cancel(timer))
1850 		hrtimer_start_expires(timer, HRTIMER_MODE_ABS);
1851 }
1852 
1853 /*
1854  * apic_sync_pv_eoi_from_guest - called on vmexit or cancel interrupt
1855  *
1856  * Detect whether guest triggered PV EOI since the
1857  * last entry. If yes, set EOI on guests's behalf.
1858  * Clear PV EOI in guest memory in any case.
1859  */
1860 static void apic_sync_pv_eoi_from_guest(struct kvm_vcpu *vcpu,
1861 					struct kvm_lapic *apic)
1862 {
1863 	bool pending;
1864 	int vector;
1865 	/*
1866 	 * PV EOI state is derived from KVM_APIC_PV_EOI_PENDING in host
1867 	 * and KVM_PV_EOI_ENABLED in guest memory as follows:
1868 	 *
1869 	 * KVM_APIC_PV_EOI_PENDING is unset:
1870 	 * 	-> host disabled PV EOI.
1871 	 * KVM_APIC_PV_EOI_PENDING is set, KVM_PV_EOI_ENABLED is set:
1872 	 * 	-> host enabled PV EOI, guest did not execute EOI yet.
1873 	 * KVM_APIC_PV_EOI_PENDING is set, KVM_PV_EOI_ENABLED is unset:
1874 	 * 	-> host enabled PV EOI, guest executed EOI.
1875 	 */
1876 	BUG_ON(!pv_eoi_enabled(vcpu));
1877 	pending = pv_eoi_get_pending(vcpu);
1878 	/*
1879 	 * Clear pending bit in any case: it will be set again on vmentry.
1880 	 * While this might not be ideal from performance point of view,
1881 	 * this makes sure pv eoi is only enabled when we know it's safe.
1882 	 */
1883 	pv_eoi_clr_pending(vcpu);
1884 	if (pending)
1885 		return;
1886 	vector = apic_set_eoi(apic);
1887 	trace_kvm_pv_eoi(apic, vector);
1888 }
1889 
1890 void kvm_lapic_sync_from_vapic(struct kvm_vcpu *vcpu)
1891 {
1892 	u32 data;
1893 
1894 	if (test_bit(KVM_APIC_PV_EOI_PENDING, &vcpu->arch.apic_attention))
1895 		apic_sync_pv_eoi_from_guest(vcpu, vcpu->arch.apic);
1896 
1897 	if (!test_bit(KVM_APIC_CHECK_VAPIC, &vcpu->arch.apic_attention))
1898 		return;
1899 
1900 	kvm_read_guest_cached(vcpu->kvm, &vcpu->arch.apic->vapic_cache, &data,
1901 				sizeof(u32));
1902 
1903 	apic_set_tpr(vcpu->arch.apic, data & 0xff);
1904 }
1905 
1906 /*
1907  * apic_sync_pv_eoi_to_guest - called before vmentry
1908  *
1909  * Detect whether it's safe to enable PV EOI and
1910  * if yes do so.
1911  */
1912 static void apic_sync_pv_eoi_to_guest(struct kvm_vcpu *vcpu,
1913 					struct kvm_lapic *apic)
1914 {
1915 	if (!pv_eoi_enabled(vcpu) ||
1916 	    /* IRR set or many bits in ISR: could be nested. */
1917 	    apic->irr_pending ||
1918 	    /* Cache not set: could be safe but we don't bother. */
1919 	    apic->highest_isr_cache == -1 ||
1920 	    /* Need EOI to update ioapic. */
1921 	    kvm_ioapic_handles_vector(vcpu->kvm, apic->highest_isr_cache)) {
1922 		/*
1923 		 * PV EOI was disabled by apic_sync_pv_eoi_from_guest
1924 		 * so we need not do anything here.
1925 		 */
1926 		return;
1927 	}
1928 
1929 	pv_eoi_set_pending(apic->vcpu);
1930 }
1931 
1932 void kvm_lapic_sync_to_vapic(struct kvm_vcpu *vcpu)
1933 {
1934 	u32 data, tpr;
1935 	int max_irr, max_isr;
1936 	struct kvm_lapic *apic = vcpu->arch.apic;
1937 
1938 	apic_sync_pv_eoi_to_guest(vcpu, apic);
1939 
1940 	if (!test_bit(KVM_APIC_CHECK_VAPIC, &vcpu->arch.apic_attention))
1941 		return;
1942 
1943 	tpr = kvm_apic_get_reg(apic, APIC_TASKPRI) & 0xff;
1944 	max_irr = apic_find_highest_irr(apic);
1945 	if (max_irr < 0)
1946 		max_irr = 0;
1947 	max_isr = apic_find_highest_isr(apic);
1948 	if (max_isr < 0)
1949 		max_isr = 0;
1950 	data = (tpr & 0xff) | ((max_isr & 0xf0) << 8) | (max_irr << 24);
1951 
1952 	kvm_write_guest_cached(vcpu->kvm, &vcpu->arch.apic->vapic_cache, &data,
1953 				sizeof(u32));
1954 }
1955 
1956 int kvm_lapic_set_vapic_addr(struct kvm_vcpu *vcpu, gpa_t vapic_addr)
1957 {
1958 	if (vapic_addr) {
1959 		if (kvm_gfn_to_hva_cache_init(vcpu->kvm,
1960 					&vcpu->arch.apic->vapic_cache,
1961 					vapic_addr, sizeof(u32)))
1962 			return -EINVAL;
1963 		__set_bit(KVM_APIC_CHECK_VAPIC, &vcpu->arch.apic_attention);
1964 	} else {
1965 		__clear_bit(KVM_APIC_CHECK_VAPIC, &vcpu->arch.apic_attention);
1966 	}
1967 
1968 	vcpu->arch.apic->vapic_addr = vapic_addr;
1969 	return 0;
1970 }
1971 
1972 int kvm_x2apic_msr_write(struct kvm_vcpu *vcpu, u32 msr, u64 data)
1973 {
1974 	struct kvm_lapic *apic = vcpu->arch.apic;
1975 	u32 reg = (msr - APIC_BASE_MSR) << 4;
1976 
1977 	if (!irqchip_in_kernel(vcpu->kvm) || !apic_x2apic_mode(apic))
1978 		return 1;
1979 
1980 	if (reg == APIC_ICR2)
1981 		return 1;
1982 
1983 	/* if this is ICR write vector before command */
1984 	if (reg == APIC_ICR)
1985 		apic_reg_write(apic, APIC_ICR2, (u32)(data >> 32));
1986 	return apic_reg_write(apic, reg, (u32)data);
1987 }
1988 
1989 int kvm_x2apic_msr_read(struct kvm_vcpu *vcpu, u32 msr, u64 *data)
1990 {
1991 	struct kvm_lapic *apic = vcpu->arch.apic;
1992 	u32 reg = (msr - APIC_BASE_MSR) << 4, low, high = 0;
1993 
1994 	if (!irqchip_in_kernel(vcpu->kvm) || !apic_x2apic_mode(apic))
1995 		return 1;
1996 
1997 	if (reg == APIC_DFR || reg == APIC_ICR2) {
1998 		apic_debug("KVM_APIC_READ: read x2apic reserved register %x\n",
1999 			   reg);
2000 		return 1;
2001 	}
2002 
2003 	if (apic_reg_read(apic, reg, 4, &low))
2004 		return 1;
2005 	if (reg == APIC_ICR)
2006 		apic_reg_read(apic, APIC_ICR2, 4, &high);
2007 
2008 	*data = (((u64)high) << 32) | low;
2009 
2010 	return 0;
2011 }
2012 
2013 int kvm_hv_vapic_msr_write(struct kvm_vcpu *vcpu, u32 reg, u64 data)
2014 {
2015 	struct kvm_lapic *apic = vcpu->arch.apic;
2016 
2017 	if (!kvm_vcpu_has_lapic(vcpu))
2018 		return 1;
2019 
2020 	/* if this is ICR write vector before command */
2021 	if (reg == APIC_ICR)
2022 		apic_reg_write(apic, APIC_ICR2, (u32)(data >> 32));
2023 	return apic_reg_write(apic, reg, (u32)data);
2024 }
2025 
2026 int kvm_hv_vapic_msr_read(struct kvm_vcpu *vcpu, u32 reg, u64 *data)
2027 {
2028 	struct kvm_lapic *apic = vcpu->arch.apic;
2029 	u32 low, high = 0;
2030 
2031 	if (!kvm_vcpu_has_lapic(vcpu))
2032 		return 1;
2033 
2034 	if (apic_reg_read(apic, reg, 4, &low))
2035 		return 1;
2036 	if (reg == APIC_ICR)
2037 		apic_reg_read(apic, APIC_ICR2, 4, &high);
2038 
2039 	*data = (((u64)high) << 32) | low;
2040 
2041 	return 0;
2042 }
2043 
2044 int kvm_lapic_enable_pv_eoi(struct kvm_vcpu *vcpu, u64 data)
2045 {
2046 	u64 addr = data & ~KVM_MSR_ENABLED;
2047 	if (!IS_ALIGNED(addr, 4))
2048 		return 1;
2049 
2050 	vcpu->arch.pv_eoi.msr_val = data;
2051 	if (!pv_eoi_enabled(vcpu))
2052 		return 0;
2053 	return kvm_gfn_to_hva_cache_init(vcpu->kvm, &vcpu->arch.pv_eoi.data,
2054 					 addr, sizeof(u8));
2055 }
2056 
2057 void kvm_apic_accept_events(struct kvm_vcpu *vcpu)
2058 {
2059 	struct kvm_lapic *apic = vcpu->arch.apic;
2060 	u8 sipi_vector;
2061 	unsigned long pe;
2062 
2063 	if (!kvm_vcpu_has_lapic(vcpu) || !apic->pending_events)
2064 		return;
2065 
2066 	/*
2067 	 * INITs are latched while in SMM.  Because an SMM CPU cannot
2068 	 * be in KVM_MP_STATE_INIT_RECEIVED state, just eat SIPIs
2069 	 * and delay processing of INIT until the next RSM.
2070 	 */
2071 	if (is_smm(vcpu)) {
2072 		WARN_ON_ONCE(vcpu->arch.mp_state == KVM_MP_STATE_INIT_RECEIVED);
2073 		if (test_bit(KVM_APIC_SIPI, &apic->pending_events))
2074 			clear_bit(KVM_APIC_SIPI, &apic->pending_events);
2075 		return;
2076 	}
2077 
2078 	pe = xchg(&apic->pending_events, 0);
2079 	if (test_bit(KVM_APIC_INIT, &pe)) {
2080 		kvm_lapic_reset(vcpu, true);
2081 		kvm_vcpu_reset(vcpu, true);
2082 		if (kvm_vcpu_is_bsp(apic->vcpu))
2083 			vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
2084 		else
2085 			vcpu->arch.mp_state = KVM_MP_STATE_INIT_RECEIVED;
2086 	}
2087 	if (test_bit(KVM_APIC_SIPI, &pe) &&
2088 	    vcpu->arch.mp_state == KVM_MP_STATE_INIT_RECEIVED) {
2089 		/* evaluate pending_events before reading the vector */
2090 		smp_rmb();
2091 		sipi_vector = apic->sipi_vector;
2092 		apic_debug("vcpu %d received sipi with vector # %x\n",
2093 			 vcpu->vcpu_id, sipi_vector);
2094 		kvm_vcpu_deliver_sipi_vector(vcpu, sipi_vector);
2095 		vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
2096 	}
2097 }
2098 
2099 void kvm_lapic_init(void)
2100 {
2101 	/* do not patch jump label more than once per second */
2102 	jump_label_rate_limit(&apic_hw_disabled, HZ);
2103 	jump_label_rate_limit(&apic_sw_disabled, HZ);
2104 }
2105