xref: /linux/arch/x86/kvm/lapic.c (revision c4ee0af3fa0dc65f690fc908f02b8355f9576ea0)
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 <linux/atomic.h>
37 #include <linux/jump_label.h>
38 #include "kvm_cache_regs.h"
39 #include "irq.h"
40 #include "trace.h"
41 #include "x86.h"
42 #include "cpuid.h"
43 
44 #ifndef CONFIG_X86_64
45 #define mod_64(x, y) ((x) - (y) * div64_u64(x, y))
46 #else
47 #define mod_64(x, y) ((x) % (y))
48 #endif
49 
50 #define PRId64 "d"
51 #define PRIx64 "llx"
52 #define PRIu64 "u"
53 #define PRIo64 "o"
54 
55 #define APIC_BUS_CYCLE_NS 1
56 
57 /* #define apic_debug(fmt,arg...) printk(KERN_WARNING fmt,##arg) */
58 #define apic_debug(fmt, arg...)
59 
60 #define APIC_LVT_NUM			6
61 /* 14 is the version for Xeon and Pentium 8.4.8*/
62 #define APIC_VERSION			(0x14UL | ((APIC_LVT_NUM - 1) << 16))
63 #define LAPIC_MMIO_LENGTH		(1 << 12)
64 /* followed define is not in apicdef.h */
65 #define APIC_SHORT_MASK			0xc0000
66 #define APIC_DEST_NOSHORT		0x0
67 #define APIC_DEST_MASK			0x800
68 #define MAX_APIC_VECTOR			256
69 #define APIC_VECTORS_PER_REG		32
70 
71 #define VEC_POS(v) ((v) & (32 - 1))
72 #define REG_POS(v) (((v) >> 5) << 4)
73 
74 static unsigned int min_timer_period_us = 500;
75 module_param(min_timer_period_us, uint, S_IRUGO | S_IWUSR);
76 
77 static inline void apic_set_reg(struct kvm_lapic *apic, int reg_off, u32 val)
78 {
79 	*((u32 *) (apic->regs + reg_off)) = val;
80 }
81 
82 static inline int apic_test_vector(int vec, void *bitmap)
83 {
84 	return test_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
85 }
86 
87 bool kvm_apic_pending_eoi(struct kvm_vcpu *vcpu, int vector)
88 {
89 	struct kvm_lapic *apic = vcpu->arch.apic;
90 
91 	return apic_test_vector(vector, apic->regs + APIC_ISR) ||
92 		apic_test_vector(vector, apic->regs + APIC_IRR);
93 }
94 
95 static inline void apic_set_vector(int vec, void *bitmap)
96 {
97 	set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
98 }
99 
100 static inline void apic_clear_vector(int vec, void *bitmap)
101 {
102 	clear_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
103 }
104 
105 static inline int __apic_test_and_set_vector(int vec, void *bitmap)
106 {
107 	return __test_and_set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
108 }
109 
110 static inline int __apic_test_and_clear_vector(int vec, void *bitmap)
111 {
112 	return __test_and_clear_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
113 }
114 
115 struct static_key_deferred apic_hw_disabled __read_mostly;
116 struct static_key_deferred apic_sw_disabled __read_mostly;
117 
118 static inline void apic_set_spiv(struct kvm_lapic *apic, u32 val)
119 {
120 	if ((kvm_apic_get_reg(apic, APIC_SPIV) ^ val) & APIC_SPIV_APIC_ENABLED) {
121 		if (val & APIC_SPIV_APIC_ENABLED)
122 			static_key_slow_dec_deferred(&apic_sw_disabled);
123 		else
124 			static_key_slow_inc(&apic_sw_disabled.key);
125 	}
126 	apic_set_reg(apic, APIC_SPIV, val);
127 }
128 
129 static inline int apic_enabled(struct kvm_lapic *apic)
130 {
131 	return kvm_apic_sw_enabled(apic) &&	kvm_apic_hw_enabled(apic);
132 }
133 
134 #define LVT_MASK	\
135 	(APIC_LVT_MASKED | APIC_SEND_PENDING | APIC_VECTOR_MASK)
136 
137 #define LINT_MASK	\
138 	(LVT_MASK | APIC_MODE_MASK | APIC_INPUT_POLARITY | \
139 	 APIC_LVT_REMOTE_IRR | APIC_LVT_LEVEL_TRIGGER)
140 
141 static inline int kvm_apic_id(struct kvm_lapic *apic)
142 {
143 	return (kvm_apic_get_reg(apic, APIC_ID) >> 24) & 0xff;
144 }
145 
146 #define KVM_X2APIC_CID_BITS 0
147 
148 static void recalculate_apic_map(struct kvm *kvm)
149 {
150 	struct kvm_apic_map *new, *old = NULL;
151 	struct kvm_vcpu *vcpu;
152 	int i;
153 
154 	new = kzalloc(sizeof(struct kvm_apic_map), GFP_KERNEL);
155 
156 	mutex_lock(&kvm->arch.apic_map_lock);
157 
158 	if (!new)
159 		goto out;
160 
161 	new->ldr_bits = 8;
162 	/* flat mode is default */
163 	new->cid_shift = 8;
164 	new->cid_mask = 0;
165 	new->lid_mask = 0xff;
166 
167 	kvm_for_each_vcpu(i, vcpu, kvm) {
168 		struct kvm_lapic *apic = vcpu->arch.apic;
169 		u16 cid, lid;
170 		u32 ldr;
171 
172 		if (!kvm_apic_present(vcpu))
173 			continue;
174 
175 		/*
176 		 * All APICs have to be configured in the same mode by an OS.
177 		 * We take advatage of this while building logical id loockup
178 		 * table. After reset APICs are in xapic/flat mode, so if we
179 		 * find apic with different setting we assume this is the mode
180 		 * OS wants all apics to be in; build lookup table accordingly.
181 		 */
182 		if (apic_x2apic_mode(apic)) {
183 			new->ldr_bits = 32;
184 			new->cid_shift = 16;
185 			new->cid_mask = (1 << KVM_X2APIC_CID_BITS) - 1;
186 			new->lid_mask = 0xffff;
187 		} else if (kvm_apic_sw_enabled(apic) &&
188 				!new->cid_mask /* flat mode */ &&
189 				kvm_apic_get_reg(apic, APIC_DFR) == APIC_DFR_CLUSTER) {
190 			new->cid_shift = 4;
191 			new->cid_mask = 0xf;
192 			new->lid_mask = 0xf;
193 		}
194 
195 		new->phys_map[kvm_apic_id(apic)] = apic;
196 
197 		ldr = kvm_apic_get_reg(apic, APIC_LDR);
198 		cid = apic_cluster_id(new, ldr);
199 		lid = apic_logical_id(new, ldr);
200 
201 		if (lid)
202 			new->logical_map[cid][ffs(lid) - 1] = apic;
203 	}
204 out:
205 	old = rcu_dereference_protected(kvm->arch.apic_map,
206 			lockdep_is_held(&kvm->arch.apic_map_lock));
207 	rcu_assign_pointer(kvm->arch.apic_map, new);
208 	mutex_unlock(&kvm->arch.apic_map_lock);
209 
210 	if (old)
211 		kfree_rcu(old, rcu);
212 
213 	kvm_vcpu_request_scan_ioapic(kvm);
214 }
215 
216 static inline void kvm_apic_set_id(struct kvm_lapic *apic, u8 id)
217 {
218 	apic_set_reg(apic, APIC_ID, id << 24);
219 	recalculate_apic_map(apic->vcpu->kvm);
220 }
221 
222 static inline void kvm_apic_set_ldr(struct kvm_lapic *apic, u32 id)
223 {
224 	apic_set_reg(apic, APIC_LDR, id);
225 	recalculate_apic_map(apic->vcpu->kvm);
226 }
227 
228 static inline int apic_lvt_enabled(struct kvm_lapic *apic, int lvt_type)
229 {
230 	return !(kvm_apic_get_reg(apic, lvt_type) & APIC_LVT_MASKED);
231 }
232 
233 static inline int apic_lvt_vector(struct kvm_lapic *apic, int lvt_type)
234 {
235 	return kvm_apic_get_reg(apic, lvt_type) & APIC_VECTOR_MASK;
236 }
237 
238 static inline int apic_lvtt_oneshot(struct kvm_lapic *apic)
239 {
240 	return ((kvm_apic_get_reg(apic, APIC_LVTT) &
241 		apic->lapic_timer.timer_mode_mask) == APIC_LVT_TIMER_ONESHOT);
242 }
243 
244 static inline int apic_lvtt_period(struct kvm_lapic *apic)
245 {
246 	return ((kvm_apic_get_reg(apic, APIC_LVTT) &
247 		apic->lapic_timer.timer_mode_mask) == APIC_LVT_TIMER_PERIODIC);
248 }
249 
250 static inline int apic_lvtt_tscdeadline(struct kvm_lapic *apic)
251 {
252 	return ((kvm_apic_get_reg(apic, APIC_LVTT) &
253 		apic->lapic_timer.timer_mode_mask) ==
254 			APIC_LVT_TIMER_TSCDEADLINE);
255 }
256 
257 static inline int apic_lvt_nmi_mode(u32 lvt_val)
258 {
259 	return (lvt_val & (APIC_MODE_MASK | APIC_LVT_MASKED)) == APIC_DM_NMI;
260 }
261 
262 void kvm_apic_set_version(struct kvm_vcpu *vcpu)
263 {
264 	struct kvm_lapic *apic = vcpu->arch.apic;
265 	struct kvm_cpuid_entry2 *feat;
266 	u32 v = APIC_VERSION;
267 
268 	if (!kvm_vcpu_has_lapic(vcpu))
269 		return;
270 
271 	feat = kvm_find_cpuid_entry(apic->vcpu, 0x1, 0);
272 	if (feat && (feat->ecx & (1 << (X86_FEATURE_X2APIC & 31))))
273 		v |= APIC_LVR_DIRECTED_EOI;
274 	apic_set_reg(apic, APIC_LVR, v);
275 }
276 
277 static const unsigned int apic_lvt_mask[APIC_LVT_NUM] = {
278 	LVT_MASK ,      /* part LVTT mask, timer mode mask added at runtime */
279 	LVT_MASK | APIC_MODE_MASK,	/* LVTTHMR */
280 	LVT_MASK | APIC_MODE_MASK,	/* LVTPC */
281 	LINT_MASK, LINT_MASK,	/* LVT0-1 */
282 	LVT_MASK		/* LVTERR */
283 };
284 
285 static int find_highest_vector(void *bitmap)
286 {
287 	int vec;
288 	u32 *reg;
289 
290 	for (vec = MAX_APIC_VECTOR - APIC_VECTORS_PER_REG;
291 	     vec >= 0; vec -= APIC_VECTORS_PER_REG) {
292 		reg = bitmap + REG_POS(vec);
293 		if (*reg)
294 			return fls(*reg) - 1 + vec;
295 	}
296 
297 	return -1;
298 }
299 
300 static u8 count_vectors(void *bitmap)
301 {
302 	int vec;
303 	u32 *reg;
304 	u8 count = 0;
305 
306 	for (vec = 0; vec < MAX_APIC_VECTOR; vec += APIC_VECTORS_PER_REG) {
307 		reg = bitmap + REG_POS(vec);
308 		count += hweight32(*reg);
309 	}
310 
311 	return count;
312 }
313 
314 void kvm_apic_update_irr(struct kvm_vcpu *vcpu, u32 *pir)
315 {
316 	u32 i, pir_val;
317 	struct kvm_lapic *apic = vcpu->arch.apic;
318 
319 	for (i = 0; i <= 7; i++) {
320 		pir_val = xchg(&pir[i], 0);
321 		if (pir_val)
322 			*((u32 *)(apic->regs + APIC_IRR + i * 0x10)) |= pir_val;
323 	}
324 }
325 EXPORT_SYMBOL_GPL(kvm_apic_update_irr);
326 
327 static inline void apic_set_irr(int vec, struct kvm_lapic *apic)
328 {
329 	apic->irr_pending = true;
330 	apic_set_vector(vec, apic->regs + APIC_IRR);
331 }
332 
333 static inline int apic_search_irr(struct kvm_lapic *apic)
334 {
335 	return find_highest_vector(apic->regs + APIC_IRR);
336 }
337 
338 static inline int apic_find_highest_irr(struct kvm_lapic *apic)
339 {
340 	int result;
341 
342 	/*
343 	 * Note that irr_pending is just a hint. It will be always
344 	 * true with virtual interrupt delivery enabled.
345 	 */
346 	if (!apic->irr_pending)
347 		return -1;
348 
349 	kvm_x86_ops->sync_pir_to_irr(apic->vcpu);
350 	result = apic_search_irr(apic);
351 	ASSERT(result == -1 || result >= 16);
352 
353 	return result;
354 }
355 
356 static inline void apic_clear_irr(int vec, struct kvm_lapic *apic)
357 {
358 	apic->irr_pending = false;
359 	apic_clear_vector(vec, apic->regs + APIC_IRR);
360 	if (apic_search_irr(apic) != -1)
361 		apic->irr_pending = true;
362 }
363 
364 static inline void apic_set_isr(int vec, struct kvm_lapic *apic)
365 {
366 	if (!__apic_test_and_set_vector(vec, apic->regs + APIC_ISR))
367 		++apic->isr_count;
368 	BUG_ON(apic->isr_count > MAX_APIC_VECTOR);
369 	/*
370 	 * ISR (in service register) bit is set when injecting an interrupt.
371 	 * The highest vector is injected. Thus the latest bit set matches
372 	 * the highest bit in ISR.
373 	 */
374 	apic->highest_isr_cache = vec;
375 }
376 
377 static inline void apic_clear_isr(int vec, struct kvm_lapic *apic)
378 {
379 	if (__apic_test_and_clear_vector(vec, apic->regs + APIC_ISR))
380 		--apic->isr_count;
381 	BUG_ON(apic->isr_count < 0);
382 	apic->highest_isr_cache = -1;
383 }
384 
385 int kvm_lapic_find_highest_irr(struct kvm_vcpu *vcpu)
386 {
387 	int highest_irr;
388 
389 	/* This may race with setting of irr in __apic_accept_irq() and
390 	 * value returned may be wrong, but kvm_vcpu_kick() in __apic_accept_irq
391 	 * will cause vmexit immediately and the value will be recalculated
392 	 * on the next vmentry.
393 	 */
394 	if (!kvm_vcpu_has_lapic(vcpu))
395 		return 0;
396 	highest_irr = apic_find_highest_irr(vcpu->arch.apic);
397 
398 	return highest_irr;
399 }
400 
401 static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode,
402 			     int vector, int level, int trig_mode,
403 			     unsigned long *dest_map);
404 
405 int kvm_apic_set_irq(struct kvm_vcpu *vcpu, struct kvm_lapic_irq *irq,
406 		unsigned long *dest_map)
407 {
408 	struct kvm_lapic *apic = vcpu->arch.apic;
409 
410 	return __apic_accept_irq(apic, irq->delivery_mode, irq->vector,
411 			irq->level, irq->trig_mode, dest_map);
412 }
413 
414 static int pv_eoi_put_user(struct kvm_vcpu *vcpu, u8 val)
415 {
416 
417 	return kvm_write_guest_cached(vcpu->kvm, &vcpu->arch.pv_eoi.data, &val,
418 				      sizeof(val));
419 }
420 
421 static int pv_eoi_get_user(struct kvm_vcpu *vcpu, u8 *val)
422 {
423 
424 	return kvm_read_guest_cached(vcpu->kvm, &vcpu->arch.pv_eoi.data, val,
425 				      sizeof(*val));
426 }
427 
428 static inline bool pv_eoi_enabled(struct kvm_vcpu *vcpu)
429 {
430 	return vcpu->arch.pv_eoi.msr_val & KVM_MSR_ENABLED;
431 }
432 
433 static bool pv_eoi_get_pending(struct kvm_vcpu *vcpu)
434 {
435 	u8 val;
436 	if (pv_eoi_get_user(vcpu, &val) < 0)
437 		apic_debug("Can't read EOI MSR value: 0x%llx\n",
438 			   (unsigned long long)vcpi->arch.pv_eoi.msr_val);
439 	return val & 0x1;
440 }
441 
442 static void pv_eoi_set_pending(struct kvm_vcpu *vcpu)
443 {
444 	if (pv_eoi_put_user(vcpu, KVM_PV_EOI_ENABLED) < 0) {
445 		apic_debug("Can't set EOI MSR value: 0x%llx\n",
446 			   (unsigned long long)vcpi->arch.pv_eoi.msr_val);
447 		return;
448 	}
449 	__set_bit(KVM_APIC_PV_EOI_PENDING, &vcpu->arch.apic_attention);
450 }
451 
452 static void pv_eoi_clr_pending(struct kvm_vcpu *vcpu)
453 {
454 	if (pv_eoi_put_user(vcpu, KVM_PV_EOI_DISABLED) < 0) {
455 		apic_debug("Can't clear EOI MSR value: 0x%llx\n",
456 			   (unsigned long long)vcpi->arch.pv_eoi.msr_val);
457 		return;
458 	}
459 	__clear_bit(KVM_APIC_PV_EOI_PENDING, &vcpu->arch.apic_attention);
460 }
461 
462 static inline int apic_find_highest_isr(struct kvm_lapic *apic)
463 {
464 	int result;
465 
466 	/* Note that isr_count is always 1 with vid enabled */
467 	if (!apic->isr_count)
468 		return -1;
469 	if (likely(apic->highest_isr_cache != -1))
470 		return apic->highest_isr_cache;
471 
472 	result = find_highest_vector(apic->regs + APIC_ISR);
473 	ASSERT(result == -1 || result >= 16);
474 
475 	return result;
476 }
477 
478 void kvm_apic_update_tmr(struct kvm_vcpu *vcpu, u32 *tmr)
479 {
480 	struct kvm_lapic *apic = vcpu->arch.apic;
481 	int i;
482 
483 	for (i = 0; i < 8; i++)
484 		apic_set_reg(apic, APIC_TMR + 0x10 * i, tmr[i]);
485 }
486 
487 static void apic_update_ppr(struct kvm_lapic *apic)
488 {
489 	u32 tpr, isrv, ppr, old_ppr;
490 	int isr;
491 
492 	old_ppr = kvm_apic_get_reg(apic, APIC_PROCPRI);
493 	tpr = kvm_apic_get_reg(apic, APIC_TASKPRI);
494 	isr = apic_find_highest_isr(apic);
495 	isrv = (isr != -1) ? isr : 0;
496 
497 	if ((tpr & 0xf0) >= (isrv & 0xf0))
498 		ppr = tpr & 0xff;
499 	else
500 		ppr = isrv & 0xf0;
501 
502 	apic_debug("vlapic %p, ppr 0x%x, isr 0x%x, isrv 0x%x",
503 		   apic, ppr, isr, isrv);
504 
505 	if (old_ppr != ppr) {
506 		apic_set_reg(apic, APIC_PROCPRI, ppr);
507 		if (ppr < old_ppr)
508 			kvm_make_request(KVM_REQ_EVENT, apic->vcpu);
509 	}
510 }
511 
512 static void apic_set_tpr(struct kvm_lapic *apic, u32 tpr)
513 {
514 	apic_set_reg(apic, APIC_TASKPRI, tpr);
515 	apic_update_ppr(apic);
516 }
517 
518 int kvm_apic_match_physical_addr(struct kvm_lapic *apic, u16 dest)
519 {
520 	return dest == 0xff || kvm_apic_id(apic) == dest;
521 }
522 
523 int kvm_apic_match_logical_addr(struct kvm_lapic *apic, u8 mda)
524 {
525 	int result = 0;
526 	u32 logical_id;
527 
528 	if (apic_x2apic_mode(apic)) {
529 		logical_id = kvm_apic_get_reg(apic, APIC_LDR);
530 		return logical_id & mda;
531 	}
532 
533 	logical_id = GET_APIC_LOGICAL_ID(kvm_apic_get_reg(apic, APIC_LDR));
534 
535 	switch (kvm_apic_get_reg(apic, APIC_DFR)) {
536 	case APIC_DFR_FLAT:
537 		if (logical_id & mda)
538 			result = 1;
539 		break;
540 	case APIC_DFR_CLUSTER:
541 		if (((logical_id >> 4) == (mda >> 0x4))
542 		    && (logical_id & mda & 0xf))
543 			result = 1;
544 		break;
545 	default:
546 		apic_debug("Bad DFR vcpu %d: %08x\n",
547 			   apic->vcpu->vcpu_id, kvm_apic_get_reg(apic, APIC_DFR));
548 		break;
549 	}
550 
551 	return result;
552 }
553 
554 int kvm_apic_match_dest(struct kvm_vcpu *vcpu, struct kvm_lapic *source,
555 			   int short_hand, int dest, int dest_mode)
556 {
557 	int result = 0;
558 	struct kvm_lapic *target = vcpu->arch.apic;
559 
560 	apic_debug("target %p, source %p, dest 0x%x, "
561 		   "dest_mode 0x%x, short_hand 0x%x\n",
562 		   target, source, dest, dest_mode, short_hand);
563 
564 	ASSERT(target);
565 	switch (short_hand) {
566 	case APIC_DEST_NOSHORT:
567 		if (dest_mode == 0)
568 			/* Physical mode. */
569 			result = kvm_apic_match_physical_addr(target, dest);
570 		else
571 			/* Logical mode. */
572 			result = kvm_apic_match_logical_addr(target, dest);
573 		break;
574 	case APIC_DEST_SELF:
575 		result = (target == source);
576 		break;
577 	case APIC_DEST_ALLINC:
578 		result = 1;
579 		break;
580 	case APIC_DEST_ALLBUT:
581 		result = (target != source);
582 		break;
583 	default:
584 		apic_debug("kvm: apic: Bad dest shorthand value %x\n",
585 			   short_hand);
586 		break;
587 	}
588 
589 	return result;
590 }
591 
592 bool kvm_irq_delivery_to_apic_fast(struct kvm *kvm, struct kvm_lapic *src,
593 		struct kvm_lapic_irq *irq, int *r, unsigned long *dest_map)
594 {
595 	struct kvm_apic_map *map;
596 	unsigned long bitmap = 1;
597 	struct kvm_lapic **dst;
598 	int i;
599 	bool ret = false;
600 
601 	*r = -1;
602 
603 	if (irq->shorthand == APIC_DEST_SELF) {
604 		*r = kvm_apic_set_irq(src->vcpu, irq, dest_map);
605 		return true;
606 	}
607 
608 	if (irq->shorthand)
609 		return false;
610 
611 	rcu_read_lock();
612 	map = rcu_dereference(kvm->arch.apic_map);
613 
614 	if (!map)
615 		goto out;
616 
617 	if (irq->dest_mode == 0) { /* physical mode */
618 		if (irq->delivery_mode == APIC_DM_LOWEST ||
619 				irq->dest_id == 0xff)
620 			goto out;
621 		dst = &map->phys_map[irq->dest_id & 0xff];
622 	} else {
623 		u32 mda = irq->dest_id << (32 - map->ldr_bits);
624 
625 		dst = map->logical_map[apic_cluster_id(map, mda)];
626 
627 		bitmap = apic_logical_id(map, mda);
628 
629 		if (irq->delivery_mode == APIC_DM_LOWEST) {
630 			int l = -1;
631 			for_each_set_bit(i, &bitmap, 16) {
632 				if (!dst[i])
633 					continue;
634 				if (l < 0)
635 					l = i;
636 				else if (kvm_apic_compare_prio(dst[i]->vcpu, dst[l]->vcpu) < 0)
637 					l = i;
638 			}
639 
640 			bitmap = (l >= 0) ? 1 << l : 0;
641 		}
642 	}
643 
644 	for_each_set_bit(i, &bitmap, 16) {
645 		if (!dst[i])
646 			continue;
647 		if (*r < 0)
648 			*r = 0;
649 		*r += kvm_apic_set_irq(dst[i]->vcpu, irq, dest_map);
650 	}
651 
652 	ret = true;
653 out:
654 	rcu_read_unlock();
655 	return ret;
656 }
657 
658 /*
659  * Add a pending IRQ into lapic.
660  * Return 1 if successfully added and 0 if discarded.
661  */
662 static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode,
663 			     int vector, int level, int trig_mode,
664 			     unsigned long *dest_map)
665 {
666 	int result = 0;
667 	struct kvm_vcpu *vcpu = apic->vcpu;
668 
669 	switch (delivery_mode) {
670 	case APIC_DM_LOWEST:
671 		vcpu->arch.apic_arb_prio++;
672 	case APIC_DM_FIXED:
673 		/* FIXME add logic for vcpu on reset */
674 		if (unlikely(!apic_enabled(apic)))
675 			break;
676 
677 		result = 1;
678 
679 		if (dest_map)
680 			__set_bit(vcpu->vcpu_id, dest_map);
681 
682 		if (kvm_x86_ops->deliver_posted_interrupt)
683 			kvm_x86_ops->deliver_posted_interrupt(vcpu, vector);
684 		else {
685 			apic_set_irr(vector, apic);
686 
687 			kvm_make_request(KVM_REQ_EVENT, vcpu);
688 			kvm_vcpu_kick(vcpu);
689 		}
690 		trace_kvm_apic_accept_irq(vcpu->vcpu_id, delivery_mode,
691 					  trig_mode, vector, false);
692 		break;
693 
694 	case APIC_DM_REMRD:
695 		result = 1;
696 		vcpu->arch.pv.pv_unhalted = 1;
697 		kvm_make_request(KVM_REQ_EVENT, vcpu);
698 		kvm_vcpu_kick(vcpu);
699 		break;
700 
701 	case APIC_DM_SMI:
702 		apic_debug("Ignoring guest SMI\n");
703 		break;
704 
705 	case APIC_DM_NMI:
706 		result = 1;
707 		kvm_inject_nmi(vcpu);
708 		kvm_vcpu_kick(vcpu);
709 		break;
710 
711 	case APIC_DM_INIT:
712 		if (!trig_mode || level) {
713 			result = 1;
714 			/* assumes that there are only KVM_APIC_INIT/SIPI */
715 			apic->pending_events = (1UL << KVM_APIC_INIT);
716 			/* make sure pending_events is visible before sending
717 			 * the request */
718 			smp_wmb();
719 			kvm_make_request(KVM_REQ_EVENT, vcpu);
720 			kvm_vcpu_kick(vcpu);
721 		} else {
722 			apic_debug("Ignoring de-assert INIT to vcpu %d\n",
723 				   vcpu->vcpu_id);
724 		}
725 		break;
726 
727 	case APIC_DM_STARTUP:
728 		apic_debug("SIPI to vcpu %d vector 0x%02x\n",
729 			   vcpu->vcpu_id, vector);
730 		result = 1;
731 		apic->sipi_vector = vector;
732 		/* make sure sipi_vector is visible for the receiver */
733 		smp_wmb();
734 		set_bit(KVM_APIC_SIPI, &apic->pending_events);
735 		kvm_make_request(KVM_REQ_EVENT, vcpu);
736 		kvm_vcpu_kick(vcpu);
737 		break;
738 
739 	case APIC_DM_EXTINT:
740 		/*
741 		 * Should only be called by kvm_apic_local_deliver() with LVT0,
742 		 * before NMI watchdog was enabled. Already handled by
743 		 * kvm_apic_accept_pic_intr().
744 		 */
745 		break;
746 
747 	default:
748 		printk(KERN_ERR "TODO: unsupported delivery mode %x\n",
749 		       delivery_mode);
750 		break;
751 	}
752 	return result;
753 }
754 
755 int kvm_apic_compare_prio(struct kvm_vcpu *vcpu1, struct kvm_vcpu *vcpu2)
756 {
757 	return vcpu1->arch.apic_arb_prio - vcpu2->arch.apic_arb_prio;
758 }
759 
760 static void kvm_ioapic_send_eoi(struct kvm_lapic *apic, int vector)
761 {
762 	if (!(kvm_apic_get_reg(apic, APIC_SPIV) & APIC_SPIV_DIRECTED_EOI) &&
763 	    kvm_ioapic_handles_vector(apic->vcpu->kvm, vector)) {
764 		int trigger_mode;
765 		if (apic_test_vector(vector, apic->regs + APIC_TMR))
766 			trigger_mode = IOAPIC_LEVEL_TRIG;
767 		else
768 			trigger_mode = IOAPIC_EDGE_TRIG;
769 		kvm_ioapic_update_eoi(apic->vcpu, vector, trigger_mode);
770 	}
771 }
772 
773 static int apic_set_eoi(struct kvm_lapic *apic)
774 {
775 	int vector = apic_find_highest_isr(apic);
776 
777 	trace_kvm_eoi(apic, vector);
778 
779 	/*
780 	 * Not every write EOI will has corresponding ISR,
781 	 * one example is when Kernel check timer on setup_IO_APIC
782 	 */
783 	if (vector == -1)
784 		return vector;
785 
786 	apic_clear_isr(vector, apic);
787 	apic_update_ppr(apic);
788 
789 	kvm_ioapic_send_eoi(apic, vector);
790 	kvm_make_request(KVM_REQ_EVENT, apic->vcpu);
791 	return vector;
792 }
793 
794 /*
795  * this interface assumes a trap-like exit, which has already finished
796  * desired side effect including vISR and vPPR update.
797  */
798 void kvm_apic_set_eoi_accelerated(struct kvm_vcpu *vcpu, int vector)
799 {
800 	struct kvm_lapic *apic = vcpu->arch.apic;
801 
802 	trace_kvm_eoi(apic, vector);
803 
804 	kvm_ioapic_send_eoi(apic, vector);
805 	kvm_make_request(KVM_REQ_EVENT, apic->vcpu);
806 }
807 EXPORT_SYMBOL_GPL(kvm_apic_set_eoi_accelerated);
808 
809 static void apic_send_ipi(struct kvm_lapic *apic)
810 {
811 	u32 icr_low = kvm_apic_get_reg(apic, APIC_ICR);
812 	u32 icr_high = kvm_apic_get_reg(apic, APIC_ICR2);
813 	struct kvm_lapic_irq irq;
814 
815 	irq.vector = icr_low & APIC_VECTOR_MASK;
816 	irq.delivery_mode = icr_low & APIC_MODE_MASK;
817 	irq.dest_mode = icr_low & APIC_DEST_MASK;
818 	irq.level = icr_low & APIC_INT_ASSERT;
819 	irq.trig_mode = icr_low & APIC_INT_LEVELTRIG;
820 	irq.shorthand = icr_low & APIC_SHORT_MASK;
821 	if (apic_x2apic_mode(apic))
822 		irq.dest_id = icr_high;
823 	else
824 		irq.dest_id = GET_APIC_DEST_FIELD(icr_high);
825 
826 	trace_kvm_apic_ipi(icr_low, irq.dest_id);
827 
828 	apic_debug("icr_high 0x%x, icr_low 0x%x, "
829 		   "short_hand 0x%x, dest 0x%x, trig_mode 0x%x, level 0x%x, "
830 		   "dest_mode 0x%x, delivery_mode 0x%x, vector 0x%x\n",
831 		   icr_high, icr_low, irq.shorthand, irq.dest_id,
832 		   irq.trig_mode, irq.level, irq.dest_mode, irq.delivery_mode,
833 		   irq.vector);
834 
835 	kvm_irq_delivery_to_apic(apic->vcpu->kvm, apic, &irq, NULL);
836 }
837 
838 static u32 apic_get_tmcct(struct kvm_lapic *apic)
839 {
840 	ktime_t remaining;
841 	s64 ns;
842 	u32 tmcct;
843 
844 	ASSERT(apic != NULL);
845 
846 	/* if initial count is 0, current count should also be 0 */
847 	if (kvm_apic_get_reg(apic, APIC_TMICT) == 0 ||
848 		apic->lapic_timer.period == 0)
849 		return 0;
850 
851 	remaining = hrtimer_get_remaining(&apic->lapic_timer.timer);
852 	if (ktime_to_ns(remaining) < 0)
853 		remaining = ktime_set(0, 0);
854 
855 	ns = mod_64(ktime_to_ns(remaining), apic->lapic_timer.period);
856 	tmcct = div64_u64(ns,
857 			 (APIC_BUS_CYCLE_NS * apic->divide_count));
858 
859 	return tmcct;
860 }
861 
862 static void __report_tpr_access(struct kvm_lapic *apic, bool write)
863 {
864 	struct kvm_vcpu *vcpu = apic->vcpu;
865 	struct kvm_run *run = vcpu->run;
866 
867 	kvm_make_request(KVM_REQ_REPORT_TPR_ACCESS, vcpu);
868 	run->tpr_access.rip = kvm_rip_read(vcpu);
869 	run->tpr_access.is_write = write;
870 }
871 
872 static inline void report_tpr_access(struct kvm_lapic *apic, bool write)
873 {
874 	if (apic->vcpu->arch.tpr_access_reporting)
875 		__report_tpr_access(apic, write);
876 }
877 
878 static u32 __apic_read(struct kvm_lapic *apic, unsigned int offset)
879 {
880 	u32 val = 0;
881 
882 	if (offset >= LAPIC_MMIO_LENGTH)
883 		return 0;
884 
885 	switch (offset) {
886 	case APIC_ID:
887 		if (apic_x2apic_mode(apic))
888 			val = kvm_apic_id(apic);
889 		else
890 			val = kvm_apic_id(apic) << 24;
891 		break;
892 	case APIC_ARBPRI:
893 		apic_debug("Access APIC ARBPRI register which is for P6\n");
894 		break;
895 
896 	case APIC_TMCCT:	/* Timer CCR */
897 		if (apic_lvtt_tscdeadline(apic))
898 			return 0;
899 
900 		val = apic_get_tmcct(apic);
901 		break;
902 	case APIC_PROCPRI:
903 		apic_update_ppr(apic);
904 		val = kvm_apic_get_reg(apic, offset);
905 		break;
906 	case APIC_TASKPRI:
907 		report_tpr_access(apic, false);
908 		/* fall thru */
909 	default:
910 		val = kvm_apic_get_reg(apic, offset);
911 		break;
912 	}
913 
914 	return val;
915 }
916 
917 static inline struct kvm_lapic *to_lapic(struct kvm_io_device *dev)
918 {
919 	return container_of(dev, struct kvm_lapic, dev);
920 }
921 
922 static int apic_reg_read(struct kvm_lapic *apic, u32 offset, int len,
923 		void *data)
924 {
925 	unsigned char alignment = offset & 0xf;
926 	u32 result;
927 	/* this bitmask has a bit cleared for each reserved register */
928 	static const u64 rmask = 0x43ff01ffffffe70cULL;
929 
930 	if ((alignment + len) > 4) {
931 		apic_debug("KVM_APIC_READ: alignment error %x %d\n",
932 			   offset, len);
933 		return 1;
934 	}
935 
936 	if (offset > 0x3f0 || !(rmask & (1ULL << (offset >> 4)))) {
937 		apic_debug("KVM_APIC_READ: read reserved register %x\n",
938 			   offset);
939 		return 1;
940 	}
941 
942 	result = __apic_read(apic, offset & ~0xf);
943 
944 	trace_kvm_apic_read(offset, result);
945 
946 	switch (len) {
947 	case 1:
948 	case 2:
949 	case 4:
950 		memcpy(data, (char *)&result + alignment, len);
951 		break;
952 	default:
953 		printk(KERN_ERR "Local APIC read with len = %x, "
954 		       "should be 1,2, or 4 instead\n", len);
955 		break;
956 	}
957 	return 0;
958 }
959 
960 static int apic_mmio_in_range(struct kvm_lapic *apic, gpa_t addr)
961 {
962 	return kvm_apic_hw_enabled(apic) &&
963 	    addr >= apic->base_address &&
964 	    addr < apic->base_address + LAPIC_MMIO_LENGTH;
965 }
966 
967 static int apic_mmio_read(struct kvm_io_device *this,
968 			   gpa_t address, int len, void *data)
969 {
970 	struct kvm_lapic *apic = to_lapic(this);
971 	u32 offset = address - apic->base_address;
972 
973 	if (!apic_mmio_in_range(apic, address))
974 		return -EOPNOTSUPP;
975 
976 	apic_reg_read(apic, offset, len, data);
977 
978 	return 0;
979 }
980 
981 static void update_divide_count(struct kvm_lapic *apic)
982 {
983 	u32 tmp1, tmp2, tdcr;
984 
985 	tdcr = kvm_apic_get_reg(apic, APIC_TDCR);
986 	tmp1 = tdcr & 0xf;
987 	tmp2 = ((tmp1 & 0x3) | ((tmp1 & 0x8) >> 1)) + 1;
988 	apic->divide_count = 0x1 << (tmp2 & 0x7);
989 
990 	apic_debug("timer divide count is 0x%x\n",
991 				   apic->divide_count);
992 }
993 
994 static void start_apic_timer(struct kvm_lapic *apic)
995 {
996 	ktime_t now;
997 	atomic_set(&apic->lapic_timer.pending, 0);
998 
999 	if (apic_lvtt_period(apic) || apic_lvtt_oneshot(apic)) {
1000 		/* lapic timer in oneshot or periodic mode */
1001 		now = apic->lapic_timer.timer.base->get_time();
1002 		apic->lapic_timer.period = (u64)kvm_apic_get_reg(apic, APIC_TMICT)
1003 			    * APIC_BUS_CYCLE_NS * apic->divide_count;
1004 
1005 		if (!apic->lapic_timer.period)
1006 			return;
1007 		/*
1008 		 * Do not allow the guest to program periodic timers with small
1009 		 * interval, since the hrtimers are not throttled by the host
1010 		 * scheduler.
1011 		 */
1012 		if (apic_lvtt_period(apic)) {
1013 			s64 min_period = min_timer_period_us * 1000LL;
1014 
1015 			if (apic->lapic_timer.period < min_period) {
1016 				pr_info_ratelimited(
1017 				    "kvm: vcpu %i: requested %lld ns "
1018 				    "lapic timer period limited to %lld ns\n",
1019 				    apic->vcpu->vcpu_id,
1020 				    apic->lapic_timer.period, min_period);
1021 				apic->lapic_timer.period = min_period;
1022 			}
1023 		}
1024 
1025 		hrtimer_start(&apic->lapic_timer.timer,
1026 			      ktime_add_ns(now, apic->lapic_timer.period),
1027 			      HRTIMER_MODE_ABS);
1028 
1029 		apic_debug("%s: bus cycle is %" PRId64 "ns, now 0x%016"
1030 			   PRIx64 ", "
1031 			   "timer initial count 0x%x, period %lldns, "
1032 			   "expire @ 0x%016" PRIx64 ".\n", __func__,
1033 			   APIC_BUS_CYCLE_NS, ktime_to_ns(now),
1034 			   kvm_apic_get_reg(apic, APIC_TMICT),
1035 			   apic->lapic_timer.period,
1036 			   ktime_to_ns(ktime_add_ns(now,
1037 					apic->lapic_timer.period)));
1038 	} else if (apic_lvtt_tscdeadline(apic)) {
1039 		/* lapic timer in tsc deadline mode */
1040 		u64 guest_tsc, tscdeadline = apic->lapic_timer.tscdeadline;
1041 		u64 ns = 0;
1042 		struct kvm_vcpu *vcpu = apic->vcpu;
1043 		unsigned long this_tsc_khz = vcpu->arch.virtual_tsc_khz;
1044 		unsigned long flags;
1045 
1046 		if (unlikely(!tscdeadline || !this_tsc_khz))
1047 			return;
1048 
1049 		local_irq_save(flags);
1050 
1051 		now = apic->lapic_timer.timer.base->get_time();
1052 		guest_tsc = kvm_x86_ops->read_l1_tsc(vcpu, native_read_tsc());
1053 		if (likely(tscdeadline > guest_tsc)) {
1054 			ns = (tscdeadline - guest_tsc) * 1000000ULL;
1055 			do_div(ns, this_tsc_khz);
1056 		}
1057 		hrtimer_start(&apic->lapic_timer.timer,
1058 			ktime_add_ns(now, ns), HRTIMER_MODE_ABS);
1059 
1060 		local_irq_restore(flags);
1061 	}
1062 }
1063 
1064 static void apic_manage_nmi_watchdog(struct kvm_lapic *apic, u32 lvt0_val)
1065 {
1066 	int nmi_wd_enabled = apic_lvt_nmi_mode(kvm_apic_get_reg(apic, APIC_LVT0));
1067 
1068 	if (apic_lvt_nmi_mode(lvt0_val)) {
1069 		if (!nmi_wd_enabled) {
1070 			apic_debug("Receive NMI setting on APIC_LVT0 "
1071 				   "for cpu %d\n", apic->vcpu->vcpu_id);
1072 			apic->vcpu->kvm->arch.vapics_in_nmi_mode++;
1073 		}
1074 	} else if (nmi_wd_enabled)
1075 		apic->vcpu->kvm->arch.vapics_in_nmi_mode--;
1076 }
1077 
1078 static int apic_reg_write(struct kvm_lapic *apic, u32 reg, u32 val)
1079 {
1080 	int ret = 0;
1081 
1082 	trace_kvm_apic_write(reg, val);
1083 
1084 	switch (reg) {
1085 	case APIC_ID:		/* Local APIC ID */
1086 		if (!apic_x2apic_mode(apic))
1087 			kvm_apic_set_id(apic, val >> 24);
1088 		else
1089 			ret = 1;
1090 		break;
1091 
1092 	case APIC_TASKPRI:
1093 		report_tpr_access(apic, true);
1094 		apic_set_tpr(apic, val & 0xff);
1095 		break;
1096 
1097 	case APIC_EOI:
1098 		apic_set_eoi(apic);
1099 		break;
1100 
1101 	case APIC_LDR:
1102 		if (!apic_x2apic_mode(apic))
1103 			kvm_apic_set_ldr(apic, val & APIC_LDR_MASK);
1104 		else
1105 			ret = 1;
1106 		break;
1107 
1108 	case APIC_DFR:
1109 		if (!apic_x2apic_mode(apic)) {
1110 			apic_set_reg(apic, APIC_DFR, val | 0x0FFFFFFF);
1111 			recalculate_apic_map(apic->vcpu->kvm);
1112 		} else
1113 			ret = 1;
1114 		break;
1115 
1116 	case APIC_SPIV: {
1117 		u32 mask = 0x3ff;
1118 		if (kvm_apic_get_reg(apic, APIC_LVR) & APIC_LVR_DIRECTED_EOI)
1119 			mask |= APIC_SPIV_DIRECTED_EOI;
1120 		apic_set_spiv(apic, val & mask);
1121 		if (!(val & APIC_SPIV_APIC_ENABLED)) {
1122 			int i;
1123 			u32 lvt_val;
1124 
1125 			for (i = 0; i < APIC_LVT_NUM; i++) {
1126 				lvt_val = kvm_apic_get_reg(apic,
1127 						       APIC_LVTT + 0x10 * i);
1128 				apic_set_reg(apic, APIC_LVTT + 0x10 * i,
1129 					     lvt_val | APIC_LVT_MASKED);
1130 			}
1131 			atomic_set(&apic->lapic_timer.pending, 0);
1132 
1133 		}
1134 		break;
1135 	}
1136 	case APIC_ICR:
1137 		/* No delay here, so we always clear the pending bit */
1138 		apic_set_reg(apic, APIC_ICR, val & ~(1 << 12));
1139 		apic_send_ipi(apic);
1140 		break;
1141 
1142 	case APIC_ICR2:
1143 		if (!apic_x2apic_mode(apic))
1144 			val &= 0xff000000;
1145 		apic_set_reg(apic, APIC_ICR2, val);
1146 		break;
1147 
1148 	case APIC_LVT0:
1149 		apic_manage_nmi_watchdog(apic, val);
1150 	case APIC_LVTTHMR:
1151 	case APIC_LVTPC:
1152 	case APIC_LVT1:
1153 	case APIC_LVTERR:
1154 		/* TODO: Check vector */
1155 		if (!kvm_apic_sw_enabled(apic))
1156 			val |= APIC_LVT_MASKED;
1157 
1158 		val &= apic_lvt_mask[(reg - APIC_LVTT) >> 4];
1159 		apic_set_reg(apic, reg, val);
1160 
1161 		break;
1162 
1163 	case APIC_LVTT:
1164 		if ((kvm_apic_get_reg(apic, APIC_LVTT) &
1165 		    apic->lapic_timer.timer_mode_mask) !=
1166 		   (val & apic->lapic_timer.timer_mode_mask))
1167 			hrtimer_cancel(&apic->lapic_timer.timer);
1168 
1169 		if (!kvm_apic_sw_enabled(apic))
1170 			val |= APIC_LVT_MASKED;
1171 		val &= (apic_lvt_mask[0] | apic->lapic_timer.timer_mode_mask);
1172 		apic_set_reg(apic, APIC_LVTT, val);
1173 		break;
1174 
1175 	case APIC_TMICT:
1176 		if (apic_lvtt_tscdeadline(apic))
1177 			break;
1178 
1179 		hrtimer_cancel(&apic->lapic_timer.timer);
1180 		apic_set_reg(apic, APIC_TMICT, val);
1181 		start_apic_timer(apic);
1182 		break;
1183 
1184 	case APIC_TDCR:
1185 		if (val & 4)
1186 			apic_debug("KVM_WRITE:TDCR %x\n", val);
1187 		apic_set_reg(apic, APIC_TDCR, val);
1188 		update_divide_count(apic);
1189 		break;
1190 
1191 	case APIC_ESR:
1192 		if (apic_x2apic_mode(apic) && val != 0) {
1193 			apic_debug("KVM_WRITE:ESR not zero %x\n", val);
1194 			ret = 1;
1195 		}
1196 		break;
1197 
1198 	case APIC_SELF_IPI:
1199 		if (apic_x2apic_mode(apic)) {
1200 			apic_reg_write(apic, APIC_ICR, 0x40000 | (val & 0xff));
1201 		} else
1202 			ret = 1;
1203 		break;
1204 	default:
1205 		ret = 1;
1206 		break;
1207 	}
1208 	if (ret)
1209 		apic_debug("Local APIC Write to read-only register %x\n", reg);
1210 	return ret;
1211 }
1212 
1213 static int apic_mmio_write(struct kvm_io_device *this,
1214 			    gpa_t address, int len, const void *data)
1215 {
1216 	struct kvm_lapic *apic = to_lapic(this);
1217 	unsigned int offset = address - apic->base_address;
1218 	u32 val;
1219 
1220 	if (!apic_mmio_in_range(apic, address))
1221 		return -EOPNOTSUPP;
1222 
1223 	/*
1224 	 * APIC register must be aligned on 128-bits boundary.
1225 	 * 32/64/128 bits registers must be accessed thru 32 bits.
1226 	 * Refer SDM 8.4.1
1227 	 */
1228 	if (len != 4 || (offset & 0xf)) {
1229 		/* Don't shout loud, $infamous_os would cause only noise. */
1230 		apic_debug("apic write: bad size=%d %lx\n", len, (long)address);
1231 		return 0;
1232 	}
1233 
1234 	val = *(u32*)data;
1235 
1236 	/* too common printing */
1237 	if (offset != APIC_EOI)
1238 		apic_debug("%s: offset 0x%x with length 0x%x, and value is "
1239 			   "0x%x\n", __func__, offset, len, val);
1240 
1241 	apic_reg_write(apic, offset & 0xff0, val);
1242 
1243 	return 0;
1244 }
1245 
1246 void kvm_lapic_set_eoi(struct kvm_vcpu *vcpu)
1247 {
1248 	if (kvm_vcpu_has_lapic(vcpu))
1249 		apic_reg_write(vcpu->arch.apic, APIC_EOI, 0);
1250 }
1251 EXPORT_SYMBOL_GPL(kvm_lapic_set_eoi);
1252 
1253 /* emulate APIC access in a trap manner */
1254 void kvm_apic_write_nodecode(struct kvm_vcpu *vcpu, u32 offset)
1255 {
1256 	u32 val = 0;
1257 
1258 	/* hw has done the conditional check and inst decode */
1259 	offset &= 0xff0;
1260 
1261 	apic_reg_read(vcpu->arch.apic, offset, 4, &val);
1262 
1263 	/* TODO: optimize to just emulate side effect w/o one more write */
1264 	apic_reg_write(vcpu->arch.apic, offset, val);
1265 }
1266 EXPORT_SYMBOL_GPL(kvm_apic_write_nodecode);
1267 
1268 void kvm_free_lapic(struct kvm_vcpu *vcpu)
1269 {
1270 	struct kvm_lapic *apic = vcpu->arch.apic;
1271 
1272 	if (!vcpu->arch.apic)
1273 		return;
1274 
1275 	hrtimer_cancel(&apic->lapic_timer.timer);
1276 
1277 	if (!(vcpu->arch.apic_base & MSR_IA32_APICBASE_ENABLE))
1278 		static_key_slow_dec_deferred(&apic_hw_disabled);
1279 
1280 	if (!(kvm_apic_get_reg(apic, APIC_SPIV) & APIC_SPIV_APIC_ENABLED))
1281 		static_key_slow_dec_deferred(&apic_sw_disabled);
1282 
1283 	if (apic->regs)
1284 		free_page((unsigned long)apic->regs);
1285 
1286 	kfree(apic);
1287 }
1288 
1289 /*
1290  *----------------------------------------------------------------------
1291  * LAPIC interface
1292  *----------------------------------------------------------------------
1293  */
1294 
1295 u64 kvm_get_lapic_tscdeadline_msr(struct kvm_vcpu *vcpu)
1296 {
1297 	struct kvm_lapic *apic = vcpu->arch.apic;
1298 
1299 	if (!kvm_vcpu_has_lapic(vcpu) || apic_lvtt_oneshot(apic) ||
1300 			apic_lvtt_period(apic))
1301 		return 0;
1302 
1303 	return apic->lapic_timer.tscdeadline;
1304 }
1305 
1306 void kvm_set_lapic_tscdeadline_msr(struct kvm_vcpu *vcpu, u64 data)
1307 {
1308 	struct kvm_lapic *apic = vcpu->arch.apic;
1309 
1310 	if (!kvm_vcpu_has_lapic(vcpu) || apic_lvtt_oneshot(apic) ||
1311 			apic_lvtt_period(apic))
1312 		return;
1313 
1314 	hrtimer_cancel(&apic->lapic_timer.timer);
1315 	apic->lapic_timer.tscdeadline = data;
1316 	start_apic_timer(apic);
1317 }
1318 
1319 void kvm_lapic_set_tpr(struct kvm_vcpu *vcpu, unsigned long cr8)
1320 {
1321 	struct kvm_lapic *apic = vcpu->arch.apic;
1322 
1323 	if (!kvm_vcpu_has_lapic(vcpu))
1324 		return;
1325 
1326 	apic_set_tpr(apic, ((cr8 & 0x0f) << 4)
1327 		     | (kvm_apic_get_reg(apic, APIC_TASKPRI) & 4));
1328 }
1329 
1330 u64 kvm_lapic_get_cr8(struct kvm_vcpu *vcpu)
1331 {
1332 	u64 tpr;
1333 
1334 	if (!kvm_vcpu_has_lapic(vcpu))
1335 		return 0;
1336 
1337 	tpr = (u64) kvm_apic_get_reg(vcpu->arch.apic, APIC_TASKPRI);
1338 
1339 	return (tpr & 0xf0) >> 4;
1340 }
1341 
1342 void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value)
1343 {
1344 	u64 old_value = vcpu->arch.apic_base;
1345 	struct kvm_lapic *apic = vcpu->arch.apic;
1346 
1347 	if (!apic) {
1348 		value |= MSR_IA32_APICBASE_BSP;
1349 		vcpu->arch.apic_base = value;
1350 		return;
1351 	}
1352 
1353 	/* update jump label if enable bit changes */
1354 	if ((vcpu->arch.apic_base ^ value) & MSR_IA32_APICBASE_ENABLE) {
1355 		if (value & MSR_IA32_APICBASE_ENABLE)
1356 			static_key_slow_dec_deferred(&apic_hw_disabled);
1357 		else
1358 			static_key_slow_inc(&apic_hw_disabled.key);
1359 		recalculate_apic_map(vcpu->kvm);
1360 	}
1361 
1362 	if (!kvm_vcpu_is_bsp(apic->vcpu))
1363 		value &= ~MSR_IA32_APICBASE_BSP;
1364 
1365 	vcpu->arch.apic_base = value;
1366 	if ((old_value ^ value) & X2APIC_ENABLE) {
1367 		if (value & X2APIC_ENABLE) {
1368 			u32 id = kvm_apic_id(apic);
1369 			u32 ldr = ((id >> 4) << 16) | (1 << (id & 0xf));
1370 			kvm_apic_set_ldr(apic, ldr);
1371 			kvm_x86_ops->set_virtual_x2apic_mode(vcpu, true);
1372 		} else
1373 			kvm_x86_ops->set_virtual_x2apic_mode(vcpu, false);
1374 	}
1375 
1376 	apic->base_address = apic->vcpu->arch.apic_base &
1377 			     MSR_IA32_APICBASE_BASE;
1378 
1379 	/* with FSB delivery interrupt, we can restart APIC functionality */
1380 	apic_debug("apic base msr is 0x%016" PRIx64 ", and base address is "
1381 		   "0x%lx.\n", apic->vcpu->arch.apic_base, apic->base_address);
1382 
1383 }
1384 
1385 void kvm_lapic_reset(struct kvm_vcpu *vcpu)
1386 {
1387 	struct kvm_lapic *apic;
1388 	int i;
1389 
1390 	apic_debug("%s\n", __func__);
1391 
1392 	ASSERT(vcpu);
1393 	apic = vcpu->arch.apic;
1394 	ASSERT(apic != NULL);
1395 
1396 	/* Stop the timer in case it's a reset to an active apic */
1397 	hrtimer_cancel(&apic->lapic_timer.timer);
1398 
1399 	kvm_apic_set_id(apic, vcpu->vcpu_id);
1400 	kvm_apic_set_version(apic->vcpu);
1401 
1402 	for (i = 0; i < APIC_LVT_NUM; i++)
1403 		apic_set_reg(apic, APIC_LVTT + 0x10 * i, APIC_LVT_MASKED);
1404 	apic_set_reg(apic, APIC_LVT0,
1405 		     SET_APIC_DELIVERY_MODE(0, APIC_MODE_EXTINT));
1406 
1407 	apic_set_reg(apic, APIC_DFR, 0xffffffffU);
1408 	apic_set_spiv(apic, 0xff);
1409 	apic_set_reg(apic, APIC_TASKPRI, 0);
1410 	kvm_apic_set_ldr(apic, 0);
1411 	apic_set_reg(apic, APIC_ESR, 0);
1412 	apic_set_reg(apic, APIC_ICR, 0);
1413 	apic_set_reg(apic, APIC_ICR2, 0);
1414 	apic_set_reg(apic, APIC_TDCR, 0);
1415 	apic_set_reg(apic, APIC_TMICT, 0);
1416 	for (i = 0; i < 8; i++) {
1417 		apic_set_reg(apic, APIC_IRR + 0x10 * i, 0);
1418 		apic_set_reg(apic, APIC_ISR + 0x10 * i, 0);
1419 		apic_set_reg(apic, APIC_TMR + 0x10 * i, 0);
1420 	}
1421 	apic->irr_pending = kvm_apic_vid_enabled(vcpu->kvm);
1422 	apic->isr_count = kvm_apic_vid_enabled(vcpu->kvm);
1423 	apic->highest_isr_cache = -1;
1424 	update_divide_count(apic);
1425 	atomic_set(&apic->lapic_timer.pending, 0);
1426 	if (kvm_vcpu_is_bsp(vcpu))
1427 		kvm_lapic_set_base(vcpu,
1428 				vcpu->arch.apic_base | MSR_IA32_APICBASE_BSP);
1429 	vcpu->arch.pv_eoi.msr_val = 0;
1430 	apic_update_ppr(apic);
1431 
1432 	vcpu->arch.apic_arb_prio = 0;
1433 	vcpu->arch.apic_attention = 0;
1434 
1435 	apic_debug(KERN_INFO "%s: vcpu=%p, id=%d, base_msr="
1436 		   "0x%016" PRIx64 ", base_address=0x%0lx.\n", __func__,
1437 		   vcpu, kvm_apic_id(apic),
1438 		   vcpu->arch.apic_base, apic->base_address);
1439 }
1440 
1441 /*
1442  *----------------------------------------------------------------------
1443  * timer interface
1444  *----------------------------------------------------------------------
1445  */
1446 
1447 static bool lapic_is_periodic(struct kvm_lapic *apic)
1448 {
1449 	return apic_lvtt_period(apic);
1450 }
1451 
1452 int apic_has_pending_timer(struct kvm_vcpu *vcpu)
1453 {
1454 	struct kvm_lapic *apic = vcpu->arch.apic;
1455 
1456 	if (kvm_vcpu_has_lapic(vcpu) && apic_enabled(apic) &&
1457 			apic_lvt_enabled(apic, APIC_LVTT))
1458 		return atomic_read(&apic->lapic_timer.pending);
1459 
1460 	return 0;
1461 }
1462 
1463 int kvm_apic_local_deliver(struct kvm_lapic *apic, int lvt_type)
1464 {
1465 	u32 reg = kvm_apic_get_reg(apic, lvt_type);
1466 	int vector, mode, trig_mode;
1467 
1468 	if (kvm_apic_hw_enabled(apic) && !(reg & APIC_LVT_MASKED)) {
1469 		vector = reg & APIC_VECTOR_MASK;
1470 		mode = reg & APIC_MODE_MASK;
1471 		trig_mode = reg & APIC_LVT_LEVEL_TRIGGER;
1472 		return __apic_accept_irq(apic, mode, vector, 1, trig_mode,
1473 					NULL);
1474 	}
1475 	return 0;
1476 }
1477 
1478 void kvm_apic_nmi_wd_deliver(struct kvm_vcpu *vcpu)
1479 {
1480 	struct kvm_lapic *apic = vcpu->arch.apic;
1481 
1482 	if (apic)
1483 		kvm_apic_local_deliver(apic, APIC_LVT0);
1484 }
1485 
1486 static const struct kvm_io_device_ops apic_mmio_ops = {
1487 	.read     = apic_mmio_read,
1488 	.write    = apic_mmio_write,
1489 };
1490 
1491 static enum hrtimer_restart apic_timer_fn(struct hrtimer *data)
1492 {
1493 	struct kvm_timer *ktimer = container_of(data, struct kvm_timer, timer);
1494 	struct kvm_lapic *apic = container_of(ktimer, struct kvm_lapic, lapic_timer);
1495 	struct kvm_vcpu *vcpu = apic->vcpu;
1496 	wait_queue_head_t *q = &vcpu->wq;
1497 
1498 	/*
1499 	 * There is a race window between reading and incrementing, but we do
1500 	 * not care about potentially losing timer events in the !reinject
1501 	 * case anyway. Note: KVM_REQ_PENDING_TIMER is implicitly checked
1502 	 * in vcpu_enter_guest.
1503 	 */
1504 	if (!atomic_read(&ktimer->pending)) {
1505 		atomic_inc(&ktimer->pending);
1506 		/* FIXME: this code should not know anything about vcpus */
1507 		kvm_make_request(KVM_REQ_PENDING_TIMER, vcpu);
1508 	}
1509 
1510 	if (waitqueue_active(q))
1511 		wake_up_interruptible(q);
1512 
1513 	if (lapic_is_periodic(apic)) {
1514 		hrtimer_add_expires_ns(&ktimer->timer, ktimer->period);
1515 		return HRTIMER_RESTART;
1516 	} else
1517 		return HRTIMER_NORESTART;
1518 }
1519 
1520 int kvm_create_lapic(struct kvm_vcpu *vcpu)
1521 {
1522 	struct kvm_lapic *apic;
1523 
1524 	ASSERT(vcpu != NULL);
1525 	apic_debug("apic_init %d\n", vcpu->vcpu_id);
1526 
1527 	apic = kzalloc(sizeof(*apic), GFP_KERNEL);
1528 	if (!apic)
1529 		goto nomem;
1530 
1531 	vcpu->arch.apic = apic;
1532 
1533 	apic->regs = (void *)get_zeroed_page(GFP_KERNEL);
1534 	if (!apic->regs) {
1535 		printk(KERN_ERR "malloc apic regs error for vcpu %x\n",
1536 		       vcpu->vcpu_id);
1537 		goto nomem_free_apic;
1538 	}
1539 	apic->vcpu = vcpu;
1540 
1541 	hrtimer_init(&apic->lapic_timer.timer, CLOCK_MONOTONIC,
1542 		     HRTIMER_MODE_ABS);
1543 	apic->lapic_timer.timer.function = apic_timer_fn;
1544 
1545 	/*
1546 	 * APIC is created enabled. This will prevent kvm_lapic_set_base from
1547 	 * thinking that APIC satet has changed.
1548 	 */
1549 	vcpu->arch.apic_base = MSR_IA32_APICBASE_ENABLE;
1550 	kvm_lapic_set_base(vcpu,
1551 			APIC_DEFAULT_PHYS_BASE | MSR_IA32_APICBASE_ENABLE);
1552 
1553 	static_key_slow_inc(&apic_sw_disabled.key); /* sw disabled at reset */
1554 	kvm_lapic_reset(vcpu);
1555 	kvm_iodevice_init(&apic->dev, &apic_mmio_ops);
1556 
1557 	return 0;
1558 nomem_free_apic:
1559 	kfree(apic);
1560 nomem:
1561 	return -ENOMEM;
1562 }
1563 
1564 int kvm_apic_has_interrupt(struct kvm_vcpu *vcpu)
1565 {
1566 	struct kvm_lapic *apic = vcpu->arch.apic;
1567 	int highest_irr;
1568 
1569 	if (!kvm_vcpu_has_lapic(vcpu) || !apic_enabled(apic))
1570 		return -1;
1571 
1572 	apic_update_ppr(apic);
1573 	highest_irr = apic_find_highest_irr(apic);
1574 	if ((highest_irr == -1) ||
1575 	    ((highest_irr & 0xF0) <= kvm_apic_get_reg(apic, APIC_PROCPRI)))
1576 		return -1;
1577 	return highest_irr;
1578 }
1579 
1580 int kvm_apic_accept_pic_intr(struct kvm_vcpu *vcpu)
1581 {
1582 	u32 lvt0 = kvm_apic_get_reg(vcpu->arch.apic, APIC_LVT0);
1583 	int r = 0;
1584 
1585 	if (!kvm_apic_hw_enabled(vcpu->arch.apic))
1586 		r = 1;
1587 	if ((lvt0 & APIC_LVT_MASKED) == 0 &&
1588 	    GET_APIC_DELIVERY_MODE(lvt0) == APIC_MODE_EXTINT)
1589 		r = 1;
1590 	return r;
1591 }
1592 
1593 void kvm_inject_apic_timer_irqs(struct kvm_vcpu *vcpu)
1594 {
1595 	struct kvm_lapic *apic = vcpu->arch.apic;
1596 
1597 	if (!kvm_vcpu_has_lapic(vcpu))
1598 		return;
1599 
1600 	if (atomic_read(&apic->lapic_timer.pending) > 0) {
1601 		kvm_apic_local_deliver(apic, APIC_LVTT);
1602 		atomic_set(&apic->lapic_timer.pending, 0);
1603 	}
1604 }
1605 
1606 int kvm_get_apic_interrupt(struct kvm_vcpu *vcpu)
1607 {
1608 	int vector = kvm_apic_has_interrupt(vcpu);
1609 	struct kvm_lapic *apic = vcpu->arch.apic;
1610 
1611 	if (vector == -1)
1612 		return -1;
1613 
1614 	apic_set_isr(vector, apic);
1615 	apic_update_ppr(apic);
1616 	apic_clear_irr(vector, apic);
1617 	return vector;
1618 }
1619 
1620 void kvm_apic_post_state_restore(struct kvm_vcpu *vcpu,
1621 		struct kvm_lapic_state *s)
1622 {
1623 	struct kvm_lapic *apic = vcpu->arch.apic;
1624 
1625 	kvm_lapic_set_base(vcpu, vcpu->arch.apic_base);
1626 	/* set SPIV separately to get count of SW disabled APICs right */
1627 	apic_set_spiv(apic, *((u32 *)(s->regs + APIC_SPIV)));
1628 	memcpy(vcpu->arch.apic->regs, s->regs, sizeof *s);
1629 	/* call kvm_apic_set_id() to put apic into apic_map */
1630 	kvm_apic_set_id(apic, kvm_apic_id(apic));
1631 	kvm_apic_set_version(vcpu);
1632 
1633 	apic_update_ppr(apic);
1634 	hrtimer_cancel(&apic->lapic_timer.timer);
1635 	update_divide_count(apic);
1636 	start_apic_timer(apic);
1637 	apic->irr_pending = true;
1638 	apic->isr_count = kvm_apic_vid_enabled(vcpu->kvm) ?
1639 				1 : count_vectors(apic->regs + APIC_ISR);
1640 	apic->highest_isr_cache = -1;
1641 	kvm_x86_ops->hwapic_isr_update(vcpu->kvm, apic_find_highest_isr(apic));
1642 	kvm_make_request(KVM_REQ_EVENT, vcpu);
1643 	kvm_rtc_eoi_tracking_restore_one(vcpu);
1644 }
1645 
1646 void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
1647 {
1648 	struct hrtimer *timer;
1649 
1650 	if (!kvm_vcpu_has_lapic(vcpu))
1651 		return;
1652 
1653 	timer = &vcpu->arch.apic->lapic_timer.timer;
1654 	if (hrtimer_cancel(timer))
1655 		hrtimer_start_expires(timer, HRTIMER_MODE_ABS);
1656 }
1657 
1658 /*
1659  * apic_sync_pv_eoi_from_guest - called on vmexit or cancel interrupt
1660  *
1661  * Detect whether guest triggered PV EOI since the
1662  * last entry. If yes, set EOI on guests's behalf.
1663  * Clear PV EOI in guest memory in any case.
1664  */
1665 static void apic_sync_pv_eoi_from_guest(struct kvm_vcpu *vcpu,
1666 					struct kvm_lapic *apic)
1667 {
1668 	bool pending;
1669 	int vector;
1670 	/*
1671 	 * PV EOI state is derived from KVM_APIC_PV_EOI_PENDING in host
1672 	 * and KVM_PV_EOI_ENABLED in guest memory as follows:
1673 	 *
1674 	 * KVM_APIC_PV_EOI_PENDING is unset:
1675 	 * 	-> host disabled PV EOI.
1676 	 * KVM_APIC_PV_EOI_PENDING is set, KVM_PV_EOI_ENABLED is set:
1677 	 * 	-> host enabled PV EOI, guest did not execute EOI yet.
1678 	 * KVM_APIC_PV_EOI_PENDING is set, KVM_PV_EOI_ENABLED is unset:
1679 	 * 	-> host enabled PV EOI, guest executed EOI.
1680 	 */
1681 	BUG_ON(!pv_eoi_enabled(vcpu));
1682 	pending = pv_eoi_get_pending(vcpu);
1683 	/*
1684 	 * Clear pending bit in any case: it will be set again on vmentry.
1685 	 * While this might not be ideal from performance point of view,
1686 	 * this makes sure pv eoi is only enabled when we know it's safe.
1687 	 */
1688 	pv_eoi_clr_pending(vcpu);
1689 	if (pending)
1690 		return;
1691 	vector = apic_set_eoi(apic);
1692 	trace_kvm_pv_eoi(apic, vector);
1693 }
1694 
1695 void kvm_lapic_sync_from_vapic(struct kvm_vcpu *vcpu)
1696 {
1697 	u32 data;
1698 
1699 	if (test_bit(KVM_APIC_PV_EOI_PENDING, &vcpu->arch.apic_attention))
1700 		apic_sync_pv_eoi_from_guest(vcpu, vcpu->arch.apic);
1701 
1702 	if (!test_bit(KVM_APIC_CHECK_VAPIC, &vcpu->arch.apic_attention))
1703 		return;
1704 
1705 	kvm_read_guest_cached(vcpu->kvm, &vcpu->arch.apic->vapic_cache, &data,
1706 				sizeof(u32));
1707 
1708 	apic_set_tpr(vcpu->arch.apic, data & 0xff);
1709 }
1710 
1711 /*
1712  * apic_sync_pv_eoi_to_guest - called before vmentry
1713  *
1714  * Detect whether it's safe to enable PV EOI and
1715  * if yes do so.
1716  */
1717 static void apic_sync_pv_eoi_to_guest(struct kvm_vcpu *vcpu,
1718 					struct kvm_lapic *apic)
1719 {
1720 	if (!pv_eoi_enabled(vcpu) ||
1721 	    /* IRR set or many bits in ISR: could be nested. */
1722 	    apic->irr_pending ||
1723 	    /* Cache not set: could be safe but we don't bother. */
1724 	    apic->highest_isr_cache == -1 ||
1725 	    /* Need EOI to update ioapic. */
1726 	    kvm_ioapic_handles_vector(vcpu->kvm, apic->highest_isr_cache)) {
1727 		/*
1728 		 * PV EOI was disabled by apic_sync_pv_eoi_from_guest
1729 		 * so we need not do anything here.
1730 		 */
1731 		return;
1732 	}
1733 
1734 	pv_eoi_set_pending(apic->vcpu);
1735 }
1736 
1737 void kvm_lapic_sync_to_vapic(struct kvm_vcpu *vcpu)
1738 {
1739 	u32 data, tpr;
1740 	int max_irr, max_isr;
1741 	struct kvm_lapic *apic = vcpu->arch.apic;
1742 
1743 	apic_sync_pv_eoi_to_guest(vcpu, apic);
1744 
1745 	if (!test_bit(KVM_APIC_CHECK_VAPIC, &vcpu->arch.apic_attention))
1746 		return;
1747 
1748 	tpr = kvm_apic_get_reg(apic, APIC_TASKPRI) & 0xff;
1749 	max_irr = apic_find_highest_irr(apic);
1750 	if (max_irr < 0)
1751 		max_irr = 0;
1752 	max_isr = apic_find_highest_isr(apic);
1753 	if (max_isr < 0)
1754 		max_isr = 0;
1755 	data = (tpr & 0xff) | ((max_isr & 0xf0) << 8) | (max_irr << 24);
1756 
1757 	kvm_write_guest_cached(vcpu->kvm, &vcpu->arch.apic->vapic_cache, &data,
1758 				sizeof(u32));
1759 }
1760 
1761 int kvm_lapic_set_vapic_addr(struct kvm_vcpu *vcpu, gpa_t vapic_addr)
1762 {
1763 	if (vapic_addr) {
1764 		if (kvm_gfn_to_hva_cache_init(vcpu->kvm,
1765 					&vcpu->arch.apic->vapic_cache,
1766 					vapic_addr, sizeof(u32)))
1767 			return -EINVAL;
1768 		__set_bit(KVM_APIC_CHECK_VAPIC, &vcpu->arch.apic_attention);
1769 	} else {
1770 		__clear_bit(KVM_APIC_CHECK_VAPIC, &vcpu->arch.apic_attention);
1771 	}
1772 
1773 	vcpu->arch.apic->vapic_addr = vapic_addr;
1774 	return 0;
1775 }
1776 
1777 int kvm_x2apic_msr_write(struct kvm_vcpu *vcpu, u32 msr, u64 data)
1778 {
1779 	struct kvm_lapic *apic = vcpu->arch.apic;
1780 	u32 reg = (msr - APIC_BASE_MSR) << 4;
1781 
1782 	if (!irqchip_in_kernel(vcpu->kvm) || !apic_x2apic_mode(apic))
1783 		return 1;
1784 
1785 	/* if this is ICR write vector before command */
1786 	if (msr == 0x830)
1787 		apic_reg_write(apic, APIC_ICR2, (u32)(data >> 32));
1788 	return apic_reg_write(apic, reg, (u32)data);
1789 }
1790 
1791 int kvm_x2apic_msr_read(struct kvm_vcpu *vcpu, u32 msr, u64 *data)
1792 {
1793 	struct kvm_lapic *apic = vcpu->arch.apic;
1794 	u32 reg = (msr - APIC_BASE_MSR) << 4, low, high = 0;
1795 
1796 	if (!irqchip_in_kernel(vcpu->kvm) || !apic_x2apic_mode(apic))
1797 		return 1;
1798 
1799 	if (apic_reg_read(apic, reg, 4, &low))
1800 		return 1;
1801 	if (msr == 0x830)
1802 		apic_reg_read(apic, APIC_ICR2, 4, &high);
1803 
1804 	*data = (((u64)high) << 32) | low;
1805 
1806 	return 0;
1807 }
1808 
1809 int kvm_hv_vapic_msr_write(struct kvm_vcpu *vcpu, u32 reg, u64 data)
1810 {
1811 	struct kvm_lapic *apic = vcpu->arch.apic;
1812 
1813 	if (!kvm_vcpu_has_lapic(vcpu))
1814 		return 1;
1815 
1816 	/* if this is ICR write vector before command */
1817 	if (reg == APIC_ICR)
1818 		apic_reg_write(apic, APIC_ICR2, (u32)(data >> 32));
1819 	return apic_reg_write(apic, reg, (u32)data);
1820 }
1821 
1822 int kvm_hv_vapic_msr_read(struct kvm_vcpu *vcpu, u32 reg, u64 *data)
1823 {
1824 	struct kvm_lapic *apic = vcpu->arch.apic;
1825 	u32 low, high = 0;
1826 
1827 	if (!kvm_vcpu_has_lapic(vcpu))
1828 		return 1;
1829 
1830 	if (apic_reg_read(apic, reg, 4, &low))
1831 		return 1;
1832 	if (reg == APIC_ICR)
1833 		apic_reg_read(apic, APIC_ICR2, 4, &high);
1834 
1835 	*data = (((u64)high) << 32) | low;
1836 
1837 	return 0;
1838 }
1839 
1840 int kvm_lapic_enable_pv_eoi(struct kvm_vcpu *vcpu, u64 data)
1841 {
1842 	u64 addr = data & ~KVM_MSR_ENABLED;
1843 	if (!IS_ALIGNED(addr, 4))
1844 		return 1;
1845 
1846 	vcpu->arch.pv_eoi.msr_val = data;
1847 	if (!pv_eoi_enabled(vcpu))
1848 		return 0;
1849 	return kvm_gfn_to_hva_cache_init(vcpu->kvm, &vcpu->arch.pv_eoi.data,
1850 					 addr, sizeof(u8));
1851 }
1852 
1853 void kvm_apic_accept_events(struct kvm_vcpu *vcpu)
1854 {
1855 	struct kvm_lapic *apic = vcpu->arch.apic;
1856 	unsigned int sipi_vector;
1857 	unsigned long pe;
1858 
1859 	if (!kvm_vcpu_has_lapic(vcpu) || !apic->pending_events)
1860 		return;
1861 
1862 	pe = xchg(&apic->pending_events, 0);
1863 
1864 	if (test_bit(KVM_APIC_INIT, &pe)) {
1865 		kvm_lapic_reset(vcpu);
1866 		kvm_vcpu_reset(vcpu);
1867 		if (kvm_vcpu_is_bsp(apic->vcpu))
1868 			vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
1869 		else
1870 			vcpu->arch.mp_state = KVM_MP_STATE_INIT_RECEIVED;
1871 	}
1872 	if (test_bit(KVM_APIC_SIPI, &pe) &&
1873 	    vcpu->arch.mp_state == KVM_MP_STATE_INIT_RECEIVED) {
1874 		/* evaluate pending_events before reading the vector */
1875 		smp_rmb();
1876 		sipi_vector = apic->sipi_vector;
1877 		pr_debug("vcpu %d received sipi with vector # %x\n",
1878 			 vcpu->vcpu_id, sipi_vector);
1879 		kvm_vcpu_deliver_sipi_vector(vcpu, sipi_vector);
1880 		vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
1881 	}
1882 }
1883 
1884 void kvm_lapic_init(void)
1885 {
1886 	/* do not patch jump label more than once per second */
1887 	jump_label_rate_limit(&apic_hw_disabled, HZ);
1888 	jump_label_rate_limit(&apic_sw_disabled, HZ);
1889 }
1890