xref: /openbmc/linux/arch/x86/kvm/lapic.c (revision 827634ad)
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 int apic_lvt_enabled(struct kvm_lapic *apic, int lvt_type)
244 {
245 	return !(kvm_apic_get_reg(apic, lvt_type) & APIC_LVT_MASKED);
246 }
247 
248 static inline int apic_lvt_vector(struct kvm_lapic *apic, int lvt_type)
249 {
250 	return kvm_apic_get_reg(apic, lvt_type) & APIC_VECTOR_MASK;
251 }
252 
253 static inline int apic_lvtt_oneshot(struct kvm_lapic *apic)
254 {
255 	return apic->lapic_timer.timer_mode == APIC_LVT_TIMER_ONESHOT;
256 }
257 
258 static inline int apic_lvtt_period(struct kvm_lapic *apic)
259 {
260 	return apic->lapic_timer.timer_mode == APIC_LVT_TIMER_PERIODIC;
261 }
262 
263 static inline int apic_lvtt_tscdeadline(struct kvm_lapic *apic)
264 {
265 	return apic->lapic_timer.timer_mode == APIC_LVT_TIMER_TSCDEADLINE;
266 }
267 
268 static inline int apic_lvt_nmi_mode(u32 lvt_val)
269 {
270 	return (lvt_val & (APIC_MODE_MASK | APIC_LVT_MASKED)) == APIC_DM_NMI;
271 }
272 
273 void kvm_apic_set_version(struct kvm_vcpu *vcpu)
274 {
275 	struct kvm_lapic *apic = vcpu->arch.apic;
276 	struct kvm_cpuid_entry2 *feat;
277 	u32 v = APIC_VERSION;
278 
279 	if (!kvm_vcpu_has_lapic(vcpu))
280 		return;
281 
282 	feat = kvm_find_cpuid_entry(apic->vcpu, 0x1, 0);
283 	if (feat && (feat->ecx & (1 << (X86_FEATURE_X2APIC & 31))))
284 		v |= APIC_LVR_DIRECTED_EOI;
285 	apic_set_reg(apic, APIC_LVR, v);
286 }
287 
288 static const unsigned int apic_lvt_mask[APIC_LVT_NUM] = {
289 	LVT_MASK ,      /* part LVTT mask, timer mode mask added at runtime */
290 	LVT_MASK | APIC_MODE_MASK,	/* LVTTHMR */
291 	LVT_MASK | APIC_MODE_MASK,	/* LVTPC */
292 	LINT_MASK, LINT_MASK,	/* LVT0-1 */
293 	LVT_MASK		/* LVTERR */
294 };
295 
296 static int find_highest_vector(void *bitmap)
297 {
298 	int vec;
299 	u32 *reg;
300 
301 	for (vec = MAX_APIC_VECTOR - APIC_VECTORS_PER_REG;
302 	     vec >= 0; vec -= APIC_VECTORS_PER_REG) {
303 		reg = bitmap + REG_POS(vec);
304 		if (*reg)
305 			return fls(*reg) - 1 + vec;
306 	}
307 
308 	return -1;
309 }
310 
311 static u8 count_vectors(void *bitmap)
312 {
313 	int vec;
314 	u32 *reg;
315 	u8 count = 0;
316 
317 	for (vec = 0; vec < MAX_APIC_VECTOR; vec += APIC_VECTORS_PER_REG) {
318 		reg = bitmap + REG_POS(vec);
319 		count += hweight32(*reg);
320 	}
321 
322 	return count;
323 }
324 
325 void __kvm_apic_update_irr(u32 *pir, void *regs)
326 {
327 	u32 i, pir_val;
328 
329 	for (i = 0; i <= 7; i++) {
330 		pir_val = xchg(&pir[i], 0);
331 		if (pir_val)
332 			*((u32 *)(regs + APIC_IRR + i * 0x10)) |= pir_val;
333 	}
334 }
335 EXPORT_SYMBOL_GPL(__kvm_apic_update_irr);
336 
337 void kvm_apic_update_irr(struct kvm_vcpu *vcpu, u32 *pir)
338 {
339 	struct kvm_lapic *apic = vcpu->arch.apic;
340 
341 	__kvm_apic_update_irr(pir, apic->regs);
342 }
343 EXPORT_SYMBOL_GPL(kvm_apic_update_irr);
344 
345 static inline void apic_set_irr(int vec, struct kvm_lapic *apic)
346 {
347 	apic_set_vector(vec, apic->regs + APIC_IRR);
348 	/*
349 	 * irr_pending must be true if any interrupt is pending; set it after
350 	 * APIC_IRR to avoid race with apic_clear_irr
351 	 */
352 	apic->irr_pending = true;
353 }
354 
355 static inline int apic_search_irr(struct kvm_lapic *apic)
356 {
357 	return find_highest_vector(apic->regs + APIC_IRR);
358 }
359 
360 static inline int apic_find_highest_irr(struct kvm_lapic *apic)
361 {
362 	int result;
363 
364 	/*
365 	 * Note that irr_pending is just a hint. It will be always
366 	 * true with virtual interrupt delivery enabled.
367 	 */
368 	if (!apic->irr_pending)
369 		return -1;
370 
371 	kvm_x86_ops->sync_pir_to_irr(apic->vcpu);
372 	result = apic_search_irr(apic);
373 	ASSERT(result == -1 || result >= 16);
374 
375 	return result;
376 }
377 
378 static inline void apic_clear_irr(int vec, struct kvm_lapic *apic)
379 {
380 	struct kvm_vcpu *vcpu;
381 
382 	vcpu = apic->vcpu;
383 
384 	if (unlikely(kvm_apic_vid_enabled(vcpu->kvm))) {
385 		/* try to update RVI */
386 		apic_clear_vector(vec, apic->regs + APIC_IRR);
387 		kvm_make_request(KVM_REQ_EVENT, vcpu);
388 	} else {
389 		apic->irr_pending = false;
390 		apic_clear_vector(vec, apic->regs + APIC_IRR);
391 		if (apic_search_irr(apic) != -1)
392 			apic->irr_pending = true;
393 	}
394 }
395 
396 static inline void apic_set_isr(int vec, struct kvm_lapic *apic)
397 {
398 	struct kvm_vcpu *vcpu;
399 
400 	if (__apic_test_and_set_vector(vec, apic->regs + APIC_ISR))
401 		return;
402 
403 	vcpu = apic->vcpu;
404 
405 	/*
406 	 * With APIC virtualization enabled, all caching is disabled
407 	 * because the processor can modify ISR under the hood.  Instead
408 	 * just set SVI.
409 	 */
410 	if (unlikely(kvm_x86_ops->hwapic_isr_update))
411 		kvm_x86_ops->hwapic_isr_update(vcpu->kvm, vec);
412 	else {
413 		++apic->isr_count;
414 		BUG_ON(apic->isr_count > MAX_APIC_VECTOR);
415 		/*
416 		 * ISR (in service register) bit is set when injecting an interrupt.
417 		 * The highest vector is injected. Thus the latest bit set matches
418 		 * the highest bit in ISR.
419 		 */
420 		apic->highest_isr_cache = vec;
421 	}
422 }
423 
424 static inline int apic_find_highest_isr(struct kvm_lapic *apic)
425 {
426 	int result;
427 
428 	/*
429 	 * Note that isr_count is always 1, and highest_isr_cache
430 	 * is always -1, with APIC virtualization enabled.
431 	 */
432 	if (!apic->isr_count)
433 		return -1;
434 	if (likely(apic->highest_isr_cache != -1))
435 		return apic->highest_isr_cache;
436 
437 	result = find_highest_vector(apic->regs + APIC_ISR);
438 	ASSERT(result == -1 || result >= 16);
439 
440 	return result;
441 }
442 
443 static inline void apic_clear_isr(int vec, struct kvm_lapic *apic)
444 {
445 	struct kvm_vcpu *vcpu;
446 	if (!__apic_test_and_clear_vector(vec, apic->regs + APIC_ISR))
447 		return;
448 
449 	vcpu = apic->vcpu;
450 
451 	/*
452 	 * We do get here for APIC virtualization enabled if the guest
453 	 * uses the Hyper-V APIC enlightenment.  In this case we may need
454 	 * to trigger a new interrupt delivery by writing the SVI field;
455 	 * on the other hand isr_count and highest_isr_cache are unused
456 	 * and must be left alone.
457 	 */
458 	if (unlikely(kvm_x86_ops->hwapic_isr_update))
459 		kvm_x86_ops->hwapic_isr_update(vcpu->kvm,
460 					       apic_find_highest_isr(apic));
461 	else {
462 		--apic->isr_count;
463 		BUG_ON(apic->isr_count < 0);
464 		apic->highest_isr_cache = -1;
465 	}
466 }
467 
468 int kvm_lapic_find_highest_irr(struct kvm_vcpu *vcpu)
469 {
470 	int highest_irr;
471 
472 	/* This may race with setting of irr in __apic_accept_irq() and
473 	 * value returned may be wrong, but kvm_vcpu_kick() in __apic_accept_irq
474 	 * will cause vmexit immediately and the value will be recalculated
475 	 * on the next vmentry.
476 	 */
477 	if (!kvm_vcpu_has_lapic(vcpu))
478 		return 0;
479 	highest_irr = apic_find_highest_irr(vcpu->arch.apic);
480 
481 	return highest_irr;
482 }
483 
484 static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode,
485 			     int vector, int level, int trig_mode,
486 			     unsigned long *dest_map);
487 
488 int kvm_apic_set_irq(struct kvm_vcpu *vcpu, struct kvm_lapic_irq *irq,
489 		unsigned long *dest_map)
490 {
491 	struct kvm_lapic *apic = vcpu->arch.apic;
492 
493 	return __apic_accept_irq(apic, irq->delivery_mode, irq->vector,
494 			irq->level, irq->trig_mode, dest_map);
495 }
496 
497 static int pv_eoi_put_user(struct kvm_vcpu *vcpu, u8 val)
498 {
499 
500 	return kvm_write_guest_cached(vcpu->kvm, &vcpu->arch.pv_eoi.data, &val,
501 				      sizeof(val));
502 }
503 
504 static int pv_eoi_get_user(struct kvm_vcpu *vcpu, u8 *val)
505 {
506 
507 	return kvm_read_guest_cached(vcpu->kvm, &vcpu->arch.pv_eoi.data, val,
508 				      sizeof(*val));
509 }
510 
511 static inline bool pv_eoi_enabled(struct kvm_vcpu *vcpu)
512 {
513 	return vcpu->arch.pv_eoi.msr_val & KVM_MSR_ENABLED;
514 }
515 
516 static bool pv_eoi_get_pending(struct kvm_vcpu *vcpu)
517 {
518 	u8 val;
519 	if (pv_eoi_get_user(vcpu, &val) < 0)
520 		apic_debug("Can't read EOI MSR value: 0x%llx\n",
521 			   (unsigned long long)vcpu->arch.pv_eoi.msr_val);
522 	return val & 0x1;
523 }
524 
525 static void pv_eoi_set_pending(struct kvm_vcpu *vcpu)
526 {
527 	if (pv_eoi_put_user(vcpu, KVM_PV_EOI_ENABLED) < 0) {
528 		apic_debug("Can't set EOI MSR value: 0x%llx\n",
529 			   (unsigned long long)vcpu->arch.pv_eoi.msr_val);
530 		return;
531 	}
532 	__set_bit(KVM_APIC_PV_EOI_PENDING, &vcpu->arch.apic_attention);
533 }
534 
535 static void pv_eoi_clr_pending(struct kvm_vcpu *vcpu)
536 {
537 	if (pv_eoi_put_user(vcpu, KVM_PV_EOI_DISABLED) < 0) {
538 		apic_debug("Can't clear EOI MSR value: 0x%llx\n",
539 			   (unsigned long long)vcpu->arch.pv_eoi.msr_val);
540 		return;
541 	}
542 	__clear_bit(KVM_APIC_PV_EOI_PENDING, &vcpu->arch.apic_attention);
543 }
544 
545 void kvm_apic_update_tmr(struct kvm_vcpu *vcpu, u32 *tmr)
546 {
547 	struct kvm_lapic *apic = vcpu->arch.apic;
548 	int i;
549 
550 	for (i = 0; i < 8; i++)
551 		apic_set_reg(apic, APIC_TMR + 0x10 * i, tmr[i]);
552 }
553 
554 static void apic_update_ppr(struct kvm_lapic *apic)
555 {
556 	u32 tpr, isrv, ppr, old_ppr;
557 	int isr;
558 
559 	old_ppr = kvm_apic_get_reg(apic, APIC_PROCPRI);
560 	tpr = kvm_apic_get_reg(apic, APIC_TASKPRI);
561 	isr = apic_find_highest_isr(apic);
562 	isrv = (isr != -1) ? isr : 0;
563 
564 	if ((tpr & 0xf0) >= (isrv & 0xf0))
565 		ppr = tpr & 0xff;
566 	else
567 		ppr = isrv & 0xf0;
568 
569 	apic_debug("vlapic %p, ppr 0x%x, isr 0x%x, isrv 0x%x",
570 		   apic, ppr, isr, isrv);
571 
572 	if (old_ppr != ppr) {
573 		apic_set_reg(apic, APIC_PROCPRI, ppr);
574 		if (ppr < old_ppr)
575 			kvm_make_request(KVM_REQ_EVENT, apic->vcpu);
576 	}
577 }
578 
579 static void apic_set_tpr(struct kvm_lapic *apic, u32 tpr)
580 {
581 	apic_set_reg(apic, APIC_TASKPRI, tpr);
582 	apic_update_ppr(apic);
583 }
584 
585 static bool kvm_apic_broadcast(struct kvm_lapic *apic, u32 mda)
586 {
587 	if (apic_x2apic_mode(apic))
588 		return mda == X2APIC_BROADCAST;
589 
590 	return GET_APIC_DEST_FIELD(mda) == APIC_BROADCAST;
591 }
592 
593 static bool kvm_apic_match_physical_addr(struct kvm_lapic *apic, u32 mda)
594 {
595 	if (kvm_apic_broadcast(apic, mda))
596 		return true;
597 
598 	if (apic_x2apic_mode(apic))
599 		return mda == kvm_apic_id(apic);
600 
601 	return mda == SET_APIC_DEST_FIELD(kvm_apic_id(apic));
602 }
603 
604 static bool kvm_apic_match_logical_addr(struct kvm_lapic *apic, u32 mda)
605 {
606 	u32 logical_id;
607 
608 	if (kvm_apic_broadcast(apic, mda))
609 		return true;
610 
611 	logical_id = kvm_apic_get_reg(apic, APIC_LDR);
612 
613 	if (apic_x2apic_mode(apic))
614 		return ((logical_id >> 16) == (mda >> 16))
615 		       && (logical_id & mda & 0xffff) != 0;
616 
617 	logical_id = GET_APIC_LOGICAL_ID(logical_id);
618 	mda = GET_APIC_DEST_FIELD(mda);
619 
620 	switch (kvm_apic_get_reg(apic, APIC_DFR)) {
621 	case APIC_DFR_FLAT:
622 		return (logical_id & mda) != 0;
623 	case APIC_DFR_CLUSTER:
624 		return ((logical_id >> 4) == (mda >> 4))
625 		       && (logical_id & mda & 0xf) != 0;
626 	default:
627 		apic_debug("Bad DFR vcpu %d: %08x\n",
628 			   apic->vcpu->vcpu_id, kvm_apic_get_reg(apic, APIC_DFR));
629 		return false;
630 	}
631 }
632 
633 /* KVM APIC implementation has two quirks
634  *  - dest always begins at 0 while xAPIC MDA has offset 24,
635  *  - IOxAPIC messages have to be delivered (directly) to x2APIC.
636  */
637 static u32 kvm_apic_mda(unsigned int dest_id, struct kvm_lapic *source,
638                                               struct kvm_lapic *target)
639 {
640 	bool ipi = source != NULL;
641 	bool x2apic_mda = apic_x2apic_mode(ipi ? source : target);
642 
643 	if (!ipi && dest_id == APIC_BROADCAST && x2apic_mda)
644 		return X2APIC_BROADCAST;
645 
646 	return x2apic_mda ? dest_id : SET_APIC_DEST_FIELD(dest_id);
647 }
648 
649 bool kvm_apic_match_dest(struct kvm_vcpu *vcpu, struct kvm_lapic *source,
650 			   int short_hand, unsigned int dest, int dest_mode)
651 {
652 	struct kvm_lapic *target = vcpu->arch.apic;
653 	u32 mda = kvm_apic_mda(dest, source, target);
654 
655 	apic_debug("target %p, source %p, dest 0x%x, "
656 		   "dest_mode 0x%x, short_hand 0x%x\n",
657 		   target, source, dest, dest_mode, short_hand);
658 
659 	ASSERT(target);
660 	switch (short_hand) {
661 	case APIC_DEST_NOSHORT:
662 		if (dest_mode == APIC_DEST_PHYSICAL)
663 			return kvm_apic_match_physical_addr(target, mda);
664 		else
665 			return kvm_apic_match_logical_addr(target, mda);
666 	case APIC_DEST_SELF:
667 		return target == source;
668 	case APIC_DEST_ALLINC:
669 		return true;
670 	case APIC_DEST_ALLBUT:
671 		return target != source;
672 	default:
673 		apic_debug("kvm: apic: Bad dest shorthand value %x\n",
674 			   short_hand);
675 		return false;
676 	}
677 }
678 
679 bool kvm_irq_delivery_to_apic_fast(struct kvm *kvm, struct kvm_lapic *src,
680 		struct kvm_lapic_irq *irq, int *r, unsigned long *dest_map)
681 {
682 	struct kvm_apic_map *map;
683 	unsigned long bitmap = 1;
684 	struct kvm_lapic **dst;
685 	int i;
686 	bool ret, x2apic_ipi;
687 
688 	*r = -1;
689 
690 	if (irq->shorthand == APIC_DEST_SELF) {
691 		*r = kvm_apic_set_irq(src->vcpu, irq, dest_map);
692 		return true;
693 	}
694 
695 	if (irq->shorthand)
696 		return false;
697 
698 	x2apic_ipi = src && apic_x2apic_mode(src);
699 	if (irq->dest_id == (x2apic_ipi ? X2APIC_BROADCAST : APIC_BROADCAST))
700 		return false;
701 
702 	ret = true;
703 	rcu_read_lock();
704 	map = rcu_dereference(kvm->arch.apic_map);
705 
706 	if (!map) {
707 		ret = false;
708 		goto out;
709 	}
710 
711 	if (irq->dest_mode == APIC_DEST_PHYSICAL) {
712 		if (irq->dest_id >= ARRAY_SIZE(map->phys_map))
713 			goto out;
714 
715 		dst = &map->phys_map[irq->dest_id];
716 	} else {
717 		u16 cid;
718 
719 		if (!kvm_apic_logical_map_valid(map)) {
720 			ret = false;
721 			goto out;
722 		}
723 
724 		apic_logical_id(map, irq->dest_id, &cid, (u16 *)&bitmap);
725 
726 		if (cid >= ARRAY_SIZE(map->logical_map))
727 			goto out;
728 
729 		dst = map->logical_map[cid];
730 
731 		if (irq->delivery_mode == APIC_DM_LOWEST) {
732 			int l = -1;
733 			for_each_set_bit(i, &bitmap, 16) {
734 				if (!dst[i])
735 					continue;
736 				if (l < 0)
737 					l = i;
738 				else if (kvm_apic_compare_prio(dst[i]->vcpu, dst[l]->vcpu) < 0)
739 					l = i;
740 			}
741 
742 			bitmap = (l >= 0) ? 1 << l : 0;
743 		}
744 	}
745 
746 	for_each_set_bit(i, &bitmap, 16) {
747 		if (!dst[i])
748 			continue;
749 		if (*r < 0)
750 			*r = 0;
751 		*r += kvm_apic_set_irq(dst[i]->vcpu, irq, dest_map);
752 	}
753 out:
754 	rcu_read_unlock();
755 	return ret;
756 }
757 
758 /*
759  * Add a pending IRQ into lapic.
760  * Return 1 if successfully added and 0 if discarded.
761  */
762 static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode,
763 			     int vector, int level, int trig_mode,
764 			     unsigned long *dest_map)
765 {
766 	int result = 0;
767 	struct kvm_vcpu *vcpu = apic->vcpu;
768 
769 	trace_kvm_apic_accept_irq(vcpu->vcpu_id, delivery_mode,
770 				  trig_mode, vector);
771 	switch (delivery_mode) {
772 	case APIC_DM_LOWEST:
773 		vcpu->arch.apic_arb_prio++;
774 	case APIC_DM_FIXED:
775 		/* FIXME add logic for vcpu on reset */
776 		if (unlikely(!apic_enabled(apic)))
777 			break;
778 
779 		result = 1;
780 
781 		if (dest_map)
782 			__set_bit(vcpu->vcpu_id, dest_map);
783 
784 		if (kvm_x86_ops->deliver_posted_interrupt)
785 			kvm_x86_ops->deliver_posted_interrupt(vcpu, vector);
786 		else {
787 			apic_set_irr(vector, apic);
788 
789 			kvm_make_request(KVM_REQ_EVENT, vcpu);
790 			kvm_vcpu_kick(vcpu);
791 		}
792 		break;
793 
794 	case APIC_DM_REMRD:
795 		result = 1;
796 		vcpu->arch.pv.pv_unhalted = 1;
797 		kvm_make_request(KVM_REQ_EVENT, vcpu);
798 		kvm_vcpu_kick(vcpu);
799 		break;
800 
801 	case APIC_DM_SMI:
802 		apic_debug("Ignoring guest SMI\n");
803 		break;
804 
805 	case APIC_DM_NMI:
806 		result = 1;
807 		kvm_inject_nmi(vcpu);
808 		kvm_vcpu_kick(vcpu);
809 		break;
810 
811 	case APIC_DM_INIT:
812 		if (!trig_mode || level) {
813 			result = 1;
814 			/* assumes that there are only KVM_APIC_INIT/SIPI */
815 			apic->pending_events = (1UL << KVM_APIC_INIT);
816 			/* make sure pending_events is visible before sending
817 			 * the request */
818 			smp_wmb();
819 			kvm_make_request(KVM_REQ_EVENT, vcpu);
820 			kvm_vcpu_kick(vcpu);
821 		} else {
822 			apic_debug("Ignoring de-assert INIT to vcpu %d\n",
823 				   vcpu->vcpu_id);
824 		}
825 		break;
826 
827 	case APIC_DM_STARTUP:
828 		apic_debug("SIPI to vcpu %d vector 0x%02x\n",
829 			   vcpu->vcpu_id, vector);
830 		result = 1;
831 		apic->sipi_vector = vector;
832 		/* make sure sipi_vector is visible for the receiver */
833 		smp_wmb();
834 		set_bit(KVM_APIC_SIPI, &apic->pending_events);
835 		kvm_make_request(KVM_REQ_EVENT, vcpu);
836 		kvm_vcpu_kick(vcpu);
837 		break;
838 
839 	case APIC_DM_EXTINT:
840 		/*
841 		 * Should only be called by kvm_apic_local_deliver() with LVT0,
842 		 * before NMI watchdog was enabled. Already handled by
843 		 * kvm_apic_accept_pic_intr().
844 		 */
845 		break;
846 
847 	default:
848 		printk(KERN_ERR "TODO: unsupported delivery mode %x\n",
849 		       delivery_mode);
850 		break;
851 	}
852 	return result;
853 }
854 
855 int kvm_apic_compare_prio(struct kvm_vcpu *vcpu1, struct kvm_vcpu *vcpu2)
856 {
857 	return vcpu1->arch.apic_arb_prio - vcpu2->arch.apic_arb_prio;
858 }
859 
860 static void kvm_ioapic_send_eoi(struct kvm_lapic *apic, int vector)
861 {
862 	if (kvm_ioapic_handles_vector(apic->vcpu->kvm, vector)) {
863 		int trigger_mode;
864 		if (apic_test_vector(vector, apic->regs + APIC_TMR))
865 			trigger_mode = IOAPIC_LEVEL_TRIG;
866 		else
867 			trigger_mode = IOAPIC_EDGE_TRIG;
868 		kvm_ioapic_update_eoi(apic->vcpu, vector, trigger_mode);
869 	}
870 }
871 
872 static int apic_set_eoi(struct kvm_lapic *apic)
873 {
874 	int vector = apic_find_highest_isr(apic);
875 
876 	trace_kvm_eoi(apic, vector);
877 
878 	/*
879 	 * Not every write EOI will has corresponding ISR,
880 	 * one example is when Kernel check timer on setup_IO_APIC
881 	 */
882 	if (vector == -1)
883 		return vector;
884 
885 	apic_clear_isr(vector, apic);
886 	apic_update_ppr(apic);
887 
888 	kvm_ioapic_send_eoi(apic, vector);
889 	kvm_make_request(KVM_REQ_EVENT, apic->vcpu);
890 	return vector;
891 }
892 
893 /*
894  * this interface assumes a trap-like exit, which has already finished
895  * desired side effect including vISR and vPPR update.
896  */
897 void kvm_apic_set_eoi_accelerated(struct kvm_vcpu *vcpu, int vector)
898 {
899 	struct kvm_lapic *apic = vcpu->arch.apic;
900 
901 	trace_kvm_eoi(apic, vector);
902 
903 	kvm_ioapic_send_eoi(apic, vector);
904 	kvm_make_request(KVM_REQ_EVENT, apic->vcpu);
905 }
906 EXPORT_SYMBOL_GPL(kvm_apic_set_eoi_accelerated);
907 
908 static void apic_send_ipi(struct kvm_lapic *apic)
909 {
910 	u32 icr_low = kvm_apic_get_reg(apic, APIC_ICR);
911 	u32 icr_high = kvm_apic_get_reg(apic, APIC_ICR2);
912 	struct kvm_lapic_irq irq;
913 
914 	irq.vector = icr_low & APIC_VECTOR_MASK;
915 	irq.delivery_mode = icr_low & APIC_MODE_MASK;
916 	irq.dest_mode = icr_low & APIC_DEST_MASK;
917 	irq.level = icr_low & APIC_INT_ASSERT;
918 	irq.trig_mode = icr_low & APIC_INT_LEVELTRIG;
919 	irq.shorthand = icr_low & APIC_SHORT_MASK;
920 	if (apic_x2apic_mode(apic))
921 		irq.dest_id = icr_high;
922 	else
923 		irq.dest_id = GET_APIC_DEST_FIELD(icr_high);
924 
925 	trace_kvm_apic_ipi(icr_low, irq.dest_id);
926 
927 	apic_debug("icr_high 0x%x, icr_low 0x%x, "
928 		   "short_hand 0x%x, dest 0x%x, trig_mode 0x%x, level 0x%x, "
929 		   "dest_mode 0x%x, delivery_mode 0x%x, vector 0x%x\n",
930 		   icr_high, icr_low, irq.shorthand, irq.dest_id,
931 		   irq.trig_mode, irq.level, irq.dest_mode, irq.delivery_mode,
932 		   irq.vector);
933 
934 	kvm_irq_delivery_to_apic(apic->vcpu->kvm, apic, &irq, NULL);
935 }
936 
937 static u32 apic_get_tmcct(struct kvm_lapic *apic)
938 {
939 	ktime_t remaining;
940 	s64 ns;
941 	u32 tmcct;
942 
943 	ASSERT(apic != NULL);
944 
945 	/* if initial count is 0, current count should also be 0 */
946 	if (kvm_apic_get_reg(apic, APIC_TMICT) == 0 ||
947 		apic->lapic_timer.period == 0)
948 		return 0;
949 
950 	remaining = hrtimer_get_remaining(&apic->lapic_timer.timer);
951 	if (ktime_to_ns(remaining) < 0)
952 		remaining = ktime_set(0, 0);
953 
954 	ns = mod_64(ktime_to_ns(remaining), apic->lapic_timer.period);
955 	tmcct = div64_u64(ns,
956 			 (APIC_BUS_CYCLE_NS * apic->divide_count));
957 
958 	return tmcct;
959 }
960 
961 static void __report_tpr_access(struct kvm_lapic *apic, bool write)
962 {
963 	struct kvm_vcpu *vcpu = apic->vcpu;
964 	struct kvm_run *run = vcpu->run;
965 
966 	kvm_make_request(KVM_REQ_REPORT_TPR_ACCESS, vcpu);
967 	run->tpr_access.rip = kvm_rip_read(vcpu);
968 	run->tpr_access.is_write = write;
969 }
970 
971 static inline void report_tpr_access(struct kvm_lapic *apic, bool write)
972 {
973 	if (apic->vcpu->arch.tpr_access_reporting)
974 		__report_tpr_access(apic, write);
975 }
976 
977 static u32 __apic_read(struct kvm_lapic *apic, unsigned int offset)
978 {
979 	u32 val = 0;
980 
981 	if (offset >= LAPIC_MMIO_LENGTH)
982 		return 0;
983 
984 	switch (offset) {
985 	case APIC_ID:
986 		if (apic_x2apic_mode(apic))
987 			val = kvm_apic_id(apic);
988 		else
989 			val = kvm_apic_id(apic) << 24;
990 		break;
991 	case APIC_ARBPRI:
992 		apic_debug("Access APIC ARBPRI register which is for P6\n");
993 		break;
994 
995 	case APIC_TMCCT:	/* Timer CCR */
996 		if (apic_lvtt_tscdeadline(apic))
997 			return 0;
998 
999 		val = apic_get_tmcct(apic);
1000 		break;
1001 	case APIC_PROCPRI:
1002 		apic_update_ppr(apic);
1003 		val = kvm_apic_get_reg(apic, offset);
1004 		break;
1005 	case APIC_TASKPRI:
1006 		report_tpr_access(apic, false);
1007 		/* fall thru */
1008 	default:
1009 		val = kvm_apic_get_reg(apic, offset);
1010 		break;
1011 	}
1012 
1013 	return val;
1014 }
1015 
1016 static inline struct kvm_lapic *to_lapic(struct kvm_io_device *dev)
1017 {
1018 	return container_of(dev, struct kvm_lapic, dev);
1019 }
1020 
1021 static int apic_reg_read(struct kvm_lapic *apic, u32 offset, int len,
1022 		void *data)
1023 {
1024 	unsigned char alignment = offset & 0xf;
1025 	u32 result;
1026 	/* this bitmask has a bit cleared for each reserved register */
1027 	static const u64 rmask = 0x43ff01ffffffe70cULL;
1028 
1029 	if ((alignment + len) > 4) {
1030 		apic_debug("KVM_APIC_READ: alignment error %x %d\n",
1031 			   offset, len);
1032 		return 1;
1033 	}
1034 
1035 	if (offset > 0x3f0 || !(rmask & (1ULL << (offset >> 4)))) {
1036 		apic_debug("KVM_APIC_READ: read reserved register %x\n",
1037 			   offset);
1038 		return 1;
1039 	}
1040 
1041 	result = __apic_read(apic, offset & ~0xf);
1042 
1043 	trace_kvm_apic_read(offset, result);
1044 
1045 	switch (len) {
1046 	case 1:
1047 	case 2:
1048 	case 4:
1049 		memcpy(data, (char *)&result + alignment, len);
1050 		break;
1051 	default:
1052 		printk(KERN_ERR "Local APIC read with len = %x, "
1053 		       "should be 1,2, or 4 instead\n", len);
1054 		break;
1055 	}
1056 	return 0;
1057 }
1058 
1059 static int apic_mmio_in_range(struct kvm_lapic *apic, gpa_t addr)
1060 {
1061 	return kvm_apic_hw_enabled(apic) &&
1062 	    addr >= apic->base_address &&
1063 	    addr < apic->base_address + LAPIC_MMIO_LENGTH;
1064 }
1065 
1066 static int apic_mmio_read(struct kvm_vcpu *vcpu, struct kvm_io_device *this,
1067 			   gpa_t address, int len, void *data)
1068 {
1069 	struct kvm_lapic *apic = to_lapic(this);
1070 	u32 offset = address - apic->base_address;
1071 
1072 	if (!apic_mmio_in_range(apic, address))
1073 		return -EOPNOTSUPP;
1074 
1075 	apic_reg_read(apic, offset, len, data);
1076 
1077 	return 0;
1078 }
1079 
1080 static void update_divide_count(struct kvm_lapic *apic)
1081 {
1082 	u32 tmp1, tmp2, tdcr;
1083 
1084 	tdcr = kvm_apic_get_reg(apic, APIC_TDCR);
1085 	tmp1 = tdcr & 0xf;
1086 	tmp2 = ((tmp1 & 0x3) | ((tmp1 & 0x8) >> 1)) + 1;
1087 	apic->divide_count = 0x1 << (tmp2 & 0x7);
1088 
1089 	apic_debug("timer divide count is 0x%x\n",
1090 				   apic->divide_count);
1091 }
1092 
1093 static void apic_timer_expired(struct kvm_lapic *apic)
1094 {
1095 	struct kvm_vcpu *vcpu = apic->vcpu;
1096 	wait_queue_head_t *q = &vcpu->wq;
1097 	struct kvm_timer *ktimer = &apic->lapic_timer;
1098 
1099 	if (atomic_read(&apic->lapic_timer.pending))
1100 		return;
1101 
1102 	atomic_inc(&apic->lapic_timer.pending);
1103 	kvm_set_pending_timer(vcpu);
1104 
1105 	if (waitqueue_active(q))
1106 		wake_up_interruptible(q);
1107 
1108 	if (apic_lvtt_tscdeadline(apic))
1109 		ktimer->expired_tscdeadline = ktimer->tscdeadline;
1110 }
1111 
1112 /*
1113  * On APICv, this test will cause a busy wait
1114  * during a higher-priority task.
1115  */
1116 
1117 static bool lapic_timer_int_injected(struct kvm_vcpu *vcpu)
1118 {
1119 	struct kvm_lapic *apic = vcpu->arch.apic;
1120 	u32 reg = kvm_apic_get_reg(apic, APIC_LVTT);
1121 
1122 	if (kvm_apic_hw_enabled(apic)) {
1123 		int vec = reg & APIC_VECTOR_MASK;
1124 		void *bitmap = apic->regs + APIC_ISR;
1125 
1126 		if (kvm_x86_ops->deliver_posted_interrupt)
1127 			bitmap = apic->regs + APIC_IRR;
1128 
1129 		if (apic_test_vector(vec, bitmap))
1130 			return true;
1131 	}
1132 	return false;
1133 }
1134 
1135 void wait_lapic_expire(struct kvm_vcpu *vcpu)
1136 {
1137 	struct kvm_lapic *apic = vcpu->arch.apic;
1138 	u64 guest_tsc, tsc_deadline;
1139 
1140 	if (!kvm_vcpu_has_lapic(vcpu))
1141 		return;
1142 
1143 	if (apic->lapic_timer.expired_tscdeadline == 0)
1144 		return;
1145 
1146 	if (!lapic_timer_int_injected(vcpu))
1147 		return;
1148 
1149 	tsc_deadline = apic->lapic_timer.expired_tscdeadline;
1150 	apic->lapic_timer.expired_tscdeadline = 0;
1151 	guest_tsc = kvm_x86_ops->read_l1_tsc(vcpu, native_read_tsc());
1152 	trace_kvm_wait_lapic_expire(vcpu->vcpu_id, guest_tsc - tsc_deadline);
1153 
1154 	/* __delay is delay_tsc whenever the hardware has TSC, thus always.  */
1155 	if (guest_tsc < tsc_deadline)
1156 		__delay(tsc_deadline - guest_tsc);
1157 }
1158 
1159 static void start_apic_timer(struct kvm_lapic *apic)
1160 {
1161 	ktime_t now;
1162 
1163 	atomic_set(&apic->lapic_timer.pending, 0);
1164 
1165 	if (apic_lvtt_period(apic) || apic_lvtt_oneshot(apic)) {
1166 		/* lapic timer in oneshot or periodic mode */
1167 		now = apic->lapic_timer.timer.base->get_time();
1168 		apic->lapic_timer.period = (u64)kvm_apic_get_reg(apic, APIC_TMICT)
1169 			    * APIC_BUS_CYCLE_NS * apic->divide_count;
1170 
1171 		if (!apic->lapic_timer.period)
1172 			return;
1173 		/*
1174 		 * Do not allow the guest to program periodic timers with small
1175 		 * interval, since the hrtimers are not throttled by the host
1176 		 * scheduler.
1177 		 */
1178 		if (apic_lvtt_period(apic)) {
1179 			s64 min_period = min_timer_period_us * 1000LL;
1180 
1181 			if (apic->lapic_timer.period < min_period) {
1182 				pr_info_ratelimited(
1183 				    "kvm: vcpu %i: requested %lld ns "
1184 				    "lapic timer period limited to %lld ns\n",
1185 				    apic->vcpu->vcpu_id,
1186 				    apic->lapic_timer.period, min_period);
1187 				apic->lapic_timer.period = min_period;
1188 			}
1189 		}
1190 
1191 		hrtimer_start(&apic->lapic_timer.timer,
1192 			      ktime_add_ns(now, apic->lapic_timer.period),
1193 			      HRTIMER_MODE_ABS);
1194 
1195 		apic_debug("%s: bus cycle is %" PRId64 "ns, now 0x%016"
1196 			   PRIx64 ", "
1197 			   "timer initial count 0x%x, period %lldns, "
1198 			   "expire @ 0x%016" PRIx64 ".\n", __func__,
1199 			   APIC_BUS_CYCLE_NS, ktime_to_ns(now),
1200 			   kvm_apic_get_reg(apic, APIC_TMICT),
1201 			   apic->lapic_timer.period,
1202 			   ktime_to_ns(ktime_add_ns(now,
1203 					apic->lapic_timer.period)));
1204 	} else if (apic_lvtt_tscdeadline(apic)) {
1205 		/* lapic timer in tsc deadline mode */
1206 		u64 guest_tsc, tscdeadline = apic->lapic_timer.tscdeadline;
1207 		u64 ns = 0;
1208 		ktime_t expire;
1209 		struct kvm_vcpu *vcpu = apic->vcpu;
1210 		unsigned long this_tsc_khz = vcpu->arch.virtual_tsc_khz;
1211 		unsigned long flags;
1212 
1213 		if (unlikely(!tscdeadline || !this_tsc_khz))
1214 			return;
1215 
1216 		local_irq_save(flags);
1217 
1218 		now = apic->lapic_timer.timer.base->get_time();
1219 		guest_tsc = kvm_x86_ops->read_l1_tsc(vcpu, native_read_tsc());
1220 		if (likely(tscdeadline > guest_tsc)) {
1221 			ns = (tscdeadline - guest_tsc) * 1000000ULL;
1222 			do_div(ns, this_tsc_khz);
1223 			expire = ktime_add_ns(now, ns);
1224 			expire = ktime_sub_ns(expire, lapic_timer_advance_ns);
1225 			hrtimer_start(&apic->lapic_timer.timer,
1226 				      expire, HRTIMER_MODE_ABS);
1227 		} else
1228 			apic_timer_expired(apic);
1229 
1230 		local_irq_restore(flags);
1231 	}
1232 }
1233 
1234 static void apic_manage_nmi_watchdog(struct kvm_lapic *apic, u32 lvt0_val)
1235 {
1236 	int nmi_wd_enabled = apic_lvt_nmi_mode(kvm_apic_get_reg(apic, APIC_LVT0));
1237 
1238 	if (apic_lvt_nmi_mode(lvt0_val)) {
1239 		if (!nmi_wd_enabled) {
1240 			apic_debug("Receive NMI setting on APIC_LVT0 "
1241 				   "for cpu %d\n", apic->vcpu->vcpu_id);
1242 			apic->vcpu->kvm->arch.vapics_in_nmi_mode++;
1243 		}
1244 	} else if (nmi_wd_enabled)
1245 		apic->vcpu->kvm->arch.vapics_in_nmi_mode--;
1246 }
1247 
1248 static int apic_reg_write(struct kvm_lapic *apic, u32 reg, u32 val)
1249 {
1250 	int ret = 0;
1251 
1252 	trace_kvm_apic_write(reg, val);
1253 
1254 	switch (reg) {
1255 	case APIC_ID:		/* Local APIC ID */
1256 		if (!apic_x2apic_mode(apic))
1257 			kvm_apic_set_id(apic, val >> 24);
1258 		else
1259 			ret = 1;
1260 		break;
1261 
1262 	case APIC_TASKPRI:
1263 		report_tpr_access(apic, true);
1264 		apic_set_tpr(apic, val & 0xff);
1265 		break;
1266 
1267 	case APIC_EOI:
1268 		apic_set_eoi(apic);
1269 		break;
1270 
1271 	case APIC_LDR:
1272 		if (!apic_x2apic_mode(apic))
1273 			kvm_apic_set_ldr(apic, val & APIC_LDR_MASK);
1274 		else
1275 			ret = 1;
1276 		break;
1277 
1278 	case APIC_DFR:
1279 		if (!apic_x2apic_mode(apic)) {
1280 			apic_set_reg(apic, APIC_DFR, val | 0x0FFFFFFF);
1281 			recalculate_apic_map(apic->vcpu->kvm);
1282 		} else
1283 			ret = 1;
1284 		break;
1285 
1286 	case APIC_SPIV: {
1287 		u32 mask = 0x3ff;
1288 		if (kvm_apic_get_reg(apic, APIC_LVR) & APIC_LVR_DIRECTED_EOI)
1289 			mask |= APIC_SPIV_DIRECTED_EOI;
1290 		apic_set_spiv(apic, val & mask);
1291 		if (!(val & APIC_SPIV_APIC_ENABLED)) {
1292 			int i;
1293 			u32 lvt_val;
1294 
1295 			for (i = 0; i < APIC_LVT_NUM; i++) {
1296 				lvt_val = kvm_apic_get_reg(apic,
1297 						       APIC_LVTT + 0x10 * i);
1298 				apic_set_reg(apic, APIC_LVTT + 0x10 * i,
1299 					     lvt_val | APIC_LVT_MASKED);
1300 			}
1301 			atomic_set(&apic->lapic_timer.pending, 0);
1302 
1303 		}
1304 		break;
1305 	}
1306 	case APIC_ICR:
1307 		/* No delay here, so we always clear the pending bit */
1308 		apic_set_reg(apic, APIC_ICR, val & ~(1 << 12));
1309 		apic_send_ipi(apic);
1310 		break;
1311 
1312 	case APIC_ICR2:
1313 		if (!apic_x2apic_mode(apic))
1314 			val &= 0xff000000;
1315 		apic_set_reg(apic, APIC_ICR2, val);
1316 		break;
1317 
1318 	case APIC_LVT0:
1319 		apic_manage_nmi_watchdog(apic, val);
1320 	case APIC_LVTTHMR:
1321 	case APIC_LVTPC:
1322 	case APIC_LVT1:
1323 	case APIC_LVTERR:
1324 		/* TODO: Check vector */
1325 		if (!kvm_apic_sw_enabled(apic))
1326 			val |= APIC_LVT_MASKED;
1327 
1328 		val &= apic_lvt_mask[(reg - APIC_LVTT) >> 4];
1329 		apic_set_reg(apic, reg, val);
1330 
1331 		break;
1332 
1333 	case APIC_LVTT: {
1334 		u32 timer_mode = val & apic->lapic_timer.timer_mode_mask;
1335 
1336 		if (apic->lapic_timer.timer_mode != timer_mode) {
1337 			apic->lapic_timer.timer_mode = timer_mode;
1338 			hrtimer_cancel(&apic->lapic_timer.timer);
1339 		}
1340 
1341 		if (!kvm_apic_sw_enabled(apic))
1342 			val |= APIC_LVT_MASKED;
1343 		val &= (apic_lvt_mask[0] | apic->lapic_timer.timer_mode_mask);
1344 		apic_set_reg(apic, APIC_LVTT, val);
1345 		break;
1346 	}
1347 
1348 	case APIC_TMICT:
1349 		if (apic_lvtt_tscdeadline(apic))
1350 			break;
1351 
1352 		hrtimer_cancel(&apic->lapic_timer.timer);
1353 		apic_set_reg(apic, APIC_TMICT, val);
1354 		start_apic_timer(apic);
1355 		break;
1356 
1357 	case APIC_TDCR:
1358 		if (val & 4)
1359 			apic_debug("KVM_WRITE:TDCR %x\n", val);
1360 		apic_set_reg(apic, APIC_TDCR, val);
1361 		update_divide_count(apic);
1362 		break;
1363 
1364 	case APIC_ESR:
1365 		if (apic_x2apic_mode(apic) && val != 0) {
1366 			apic_debug("KVM_WRITE:ESR not zero %x\n", val);
1367 			ret = 1;
1368 		}
1369 		break;
1370 
1371 	case APIC_SELF_IPI:
1372 		if (apic_x2apic_mode(apic)) {
1373 			apic_reg_write(apic, APIC_ICR, 0x40000 | (val & 0xff));
1374 		} else
1375 			ret = 1;
1376 		break;
1377 	default:
1378 		ret = 1;
1379 		break;
1380 	}
1381 	if (ret)
1382 		apic_debug("Local APIC Write to read-only register %x\n", reg);
1383 	return ret;
1384 }
1385 
1386 static int apic_mmio_write(struct kvm_vcpu *vcpu, struct kvm_io_device *this,
1387 			    gpa_t address, int len, const void *data)
1388 {
1389 	struct kvm_lapic *apic = to_lapic(this);
1390 	unsigned int offset = address - apic->base_address;
1391 	u32 val;
1392 
1393 	if (!apic_mmio_in_range(apic, address))
1394 		return -EOPNOTSUPP;
1395 
1396 	/*
1397 	 * APIC register must be aligned on 128-bits boundary.
1398 	 * 32/64/128 bits registers must be accessed thru 32 bits.
1399 	 * Refer SDM 8.4.1
1400 	 */
1401 	if (len != 4 || (offset & 0xf)) {
1402 		/* Don't shout loud, $infamous_os would cause only noise. */
1403 		apic_debug("apic write: bad size=%d %lx\n", len, (long)address);
1404 		return 0;
1405 	}
1406 
1407 	val = *(u32*)data;
1408 
1409 	/* too common printing */
1410 	if (offset != APIC_EOI)
1411 		apic_debug("%s: offset 0x%x with length 0x%x, and value is "
1412 			   "0x%x\n", __func__, offset, len, val);
1413 
1414 	apic_reg_write(apic, offset & 0xff0, val);
1415 
1416 	return 0;
1417 }
1418 
1419 void kvm_lapic_set_eoi(struct kvm_vcpu *vcpu)
1420 {
1421 	if (kvm_vcpu_has_lapic(vcpu))
1422 		apic_reg_write(vcpu->arch.apic, APIC_EOI, 0);
1423 }
1424 EXPORT_SYMBOL_GPL(kvm_lapic_set_eoi);
1425 
1426 /* emulate APIC access in a trap manner */
1427 void kvm_apic_write_nodecode(struct kvm_vcpu *vcpu, u32 offset)
1428 {
1429 	u32 val = 0;
1430 
1431 	/* hw has done the conditional check and inst decode */
1432 	offset &= 0xff0;
1433 
1434 	apic_reg_read(vcpu->arch.apic, offset, 4, &val);
1435 
1436 	/* TODO: optimize to just emulate side effect w/o one more write */
1437 	apic_reg_write(vcpu->arch.apic, offset, val);
1438 }
1439 EXPORT_SYMBOL_GPL(kvm_apic_write_nodecode);
1440 
1441 void kvm_free_lapic(struct kvm_vcpu *vcpu)
1442 {
1443 	struct kvm_lapic *apic = vcpu->arch.apic;
1444 
1445 	if (!vcpu->arch.apic)
1446 		return;
1447 
1448 	hrtimer_cancel(&apic->lapic_timer.timer);
1449 
1450 	if (!(vcpu->arch.apic_base & MSR_IA32_APICBASE_ENABLE))
1451 		static_key_slow_dec_deferred(&apic_hw_disabled);
1452 
1453 	if (!apic->sw_enabled)
1454 		static_key_slow_dec_deferred(&apic_sw_disabled);
1455 
1456 	if (apic->regs)
1457 		free_page((unsigned long)apic->regs);
1458 
1459 	kfree(apic);
1460 }
1461 
1462 /*
1463  *----------------------------------------------------------------------
1464  * LAPIC interface
1465  *----------------------------------------------------------------------
1466  */
1467 
1468 u64 kvm_get_lapic_tscdeadline_msr(struct kvm_vcpu *vcpu)
1469 {
1470 	struct kvm_lapic *apic = vcpu->arch.apic;
1471 
1472 	if (!kvm_vcpu_has_lapic(vcpu) || apic_lvtt_oneshot(apic) ||
1473 			apic_lvtt_period(apic))
1474 		return 0;
1475 
1476 	return apic->lapic_timer.tscdeadline;
1477 }
1478 
1479 void kvm_set_lapic_tscdeadline_msr(struct kvm_vcpu *vcpu, u64 data)
1480 {
1481 	struct kvm_lapic *apic = vcpu->arch.apic;
1482 
1483 	if (!kvm_vcpu_has_lapic(vcpu) || apic_lvtt_oneshot(apic) ||
1484 			apic_lvtt_period(apic))
1485 		return;
1486 
1487 	hrtimer_cancel(&apic->lapic_timer.timer);
1488 	apic->lapic_timer.tscdeadline = data;
1489 	start_apic_timer(apic);
1490 }
1491 
1492 void kvm_lapic_set_tpr(struct kvm_vcpu *vcpu, unsigned long cr8)
1493 {
1494 	struct kvm_lapic *apic = vcpu->arch.apic;
1495 
1496 	if (!kvm_vcpu_has_lapic(vcpu))
1497 		return;
1498 
1499 	apic_set_tpr(apic, ((cr8 & 0x0f) << 4)
1500 		     | (kvm_apic_get_reg(apic, APIC_TASKPRI) & 4));
1501 }
1502 
1503 u64 kvm_lapic_get_cr8(struct kvm_vcpu *vcpu)
1504 {
1505 	u64 tpr;
1506 
1507 	if (!kvm_vcpu_has_lapic(vcpu))
1508 		return 0;
1509 
1510 	tpr = (u64) kvm_apic_get_reg(vcpu->arch.apic, APIC_TASKPRI);
1511 
1512 	return (tpr & 0xf0) >> 4;
1513 }
1514 
1515 void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value)
1516 {
1517 	u64 old_value = vcpu->arch.apic_base;
1518 	struct kvm_lapic *apic = vcpu->arch.apic;
1519 
1520 	if (!apic) {
1521 		value |= MSR_IA32_APICBASE_BSP;
1522 		vcpu->arch.apic_base = value;
1523 		return;
1524 	}
1525 
1526 	vcpu->arch.apic_base = value;
1527 
1528 	/* update jump label if enable bit changes */
1529 	if ((old_value ^ value) & MSR_IA32_APICBASE_ENABLE) {
1530 		if (value & MSR_IA32_APICBASE_ENABLE)
1531 			static_key_slow_dec_deferred(&apic_hw_disabled);
1532 		else
1533 			static_key_slow_inc(&apic_hw_disabled.key);
1534 		recalculate_apic_map(vcpu->kvm);
1535 	}
1536 
1537 	if ((old_value ^ value) & X2APIC_ENABLE) {
1538 		if (value & X2APIC_ENABLE) {
1539 			u32 id = kvm_apic_id(apic);
1540 			u32 ldr = ((id >> 4) << 16) | (1 << (id & 0xf));
1541 			kvm_apic_set_ldr(apic, ldr);
1542 			kvm_x86_ops->set_virtual_x2apic_mode(vcpu, true);
1543 		} else
1544 			kvm_x86_ops->set_virtual_x2apic_mode(vcpu, false);
1545 	}
1546 
1547 	apic->base_address = apic->vcpu->arch.apic_base &
1548 			     MSR_IA32_APICBASE_BASE;
1549 
1550 	if ((value & MSR_IA32_APICBASE_ENABLE) &&
1551 	     apic->base_address != APIC_DEFAULT_PHYS_BASE)
1552 		pr_warn_once("APIC base relocation is unsupported by KVM");
1553 
1554 	/* with FSB delivery interrupt, we can restart APIC functionality */
1555 	apic_debug("apic base msr is 0x%016" PRIx64 ", and base address is "
1556 		   "0x%lx.\n", apic->vcpu->arch.apic_base, apic->base_address);
1557 
1558 }
1559 
1560 void kvm_lapic_reset(struct kvm_vcpu *vcpu)
1561 {
1562 	struct kvm_lapic *apic;
1563 	int i;
1564 
1565 	apic_debug("%s\n", __func__);
1566 
1567 	ASSERT(vcpu);
1568 	apic = vcpu->arch.apic;
1569 	ASSERT(apic != NULL);
1570 
1571 	/* Stop the timer in case it's a reset to an active apic */
1572 	hrtimer_cancel(&apic->lapic_timer.timer);
1573 
1574 	kvm_apic_set_id(apic, vcpu->vcpu_id);
1575 	kvm_apic_set_version(apic->vcpu);
1576 
1577 	for (i = 0; i < APIC_LVT_NUM; i++)
1578 		apic_set_reg(apic, APIC_LVTT + 0x10 * i, APIC_LVT_MASKED);
1579 	apic->lapic_timer.timer_mode = 0;
1580 	apic_set_reg(apic, APIC_LVT0,
1581 		     SET_APIC_DELIVERY_MODE(0, APIC_MODE_EXTINT));
1582 
1583 	apic_set_reg(apic, APIC_DFR, 0xffffffffU);
1584 	apic_set_spiv(apic, 0xff);
1585 	apic_set_reg(apic, APIC_TASKPRI, 0);
1586 	kvm_apic_set_ldr(apic, 0);
1587 	apic_set_reg(apic, APIC_ESR, 0);
1588 	apic_set_reg(apic, APIC_ICR, 0);
1589 	apic_set_reg(apic, APIC_ICR2, 0);
1590 	apic_set_reg(apic, APIC_TDCR, 0);
1591 	apic_set_reg(apic, APIC_TMICT, 0);
1592 	for (i = 0; i < 8; i++) {
1593 		apic_set_reg(apic, APIC_IRR + 0x10 * i, 0);
1594 		apic_set_reg(apic, APIC_ISR + 0x10 * i, 0);
1595 		apic_set_reg(apic, APIC_TMR + 0x10 * i, 0);
1596 	}
1597 	apic->irr_pending = kvm_apic_vid_enabled(vcpu->kvm);
1598 	apic->isr_count = kvm_x86_ops->hwapic_isr_update ? 1 : 0;
1599 	apic->highest_isr_cache = -1;
1600 	update_divide_count(apic);
1601 	atomic_set(&apic->lapic_timer.pending, 0);
1602 	if (kvm_vcpu_is_bsp(vcpu))
1603 		kvm_lapic_set_base(vcpu,
1604 				vcpu->arch.apic_base | MSR_IA32_APICBASE_BSP);
1605 	vcpu->arch.pv_eoi.msr_val = 0;
1606 	apic_update_ppr(apic);
1607 
1608 	vcpu->arch.apic_arb_prio = 0;
1609 	vcpu->arch.apic_attention = 0;
1610 
1611 	apic_debug("%s: vcpu=%p, id=%d, base_msr="
1612 		   "0x%016" PRIx64 ", base_address=0x%0lx.\n", __func__,
1613 		   vcpu, kvm_apic_id(apic),
1614 		   vcpu->arch.apic_base, apic->base_address);
1615 }
1616 
1617 /*
1618  *----------------------------------------------------------------------
1619  * timer interface
1620  *----------------------------------------------------------------------
1621  */
1622 
1623 static bool lapic_is_periodic(struct kvm_lapic *apic)
1624 {
1625 	return apic_lvtt_period(apic);
1626 }
1627 
1628 int apic_has_pending_timer(struct kvm_vcpu *vcpu)
1629 {
1630 	struct kvm_lapic *apic = vcpu->arch.apic;
1631 
1632 	if (kvm_vcpu_has_lapic(vcpu) && apic_enabled(apic) &&
1633 			apic_lvt_enabled(apic, APIC_LVTT))
1634 		return atomic_read(&apic->lapic_timer.pending);
1635 
1636 	return 0;
1637 }
1638 
1639 int kvm_apic_local_deliver(struct kvm_lapic *apic, int lvt_type)
1640 {
1641 	u32 reg = kvm_apic_get_reg(apic, lvt_type);
1642 	int vector, mode, trig_mode;
1643 
1644 	if (kvm_apic_hw_enabled(apic) && !(reg & APIC_LVT_MASKED)) {
1645 		vector = reg & APIC_VECTOR_MASK;
1646 		mode = reg & APIC_MODE_MASK;
1647 		trig_mode = reg & APIC_LVT_LEVEL_TRIGGER;
1648 		return __apic_accept_irq(apic, mode, vector, 1, trig_mode,
1649 					NULL);
1650 	}
1651 	return 0;
1652 }
1653 
1654 void kvm_apic_nmi_wd_deliver(struct kvm_vcpu *vcpu)
1655 {
1656 	struct kvm_lapic *apic = vcpu->arch.apic;
1657 
1658 	if (apic)
1659 		kvm_apic_local_deliver(apic, APIC_LVT0);
1660 }
1661 
1662 static const struct kvm_io_device_ops apic_mmio_ops = {
1663 	.read     = apic_mmio_read,
1664 	.write    = apic_mmio_write,
1665 };
1666 
1667 static enum hrtimer_restart apic_timer_fn(struct hrtimer *data)
1668 {
1669 	struct kvm_timer *ktimer = container_of(data, struct kvm_timer, timer);
1670 	struct kvm_lapic *apic = container_of(ktimer, struct kvm_lapic, lapic_timer);
1671 
1672 	apic_timer_expired(apic);
1673 
1674 	if (lapic_is_periodic(apic)) {
1675 		hrtimer_add_expires_ns(&ktimer->timer, ktimer->period);
1676 		return HRTIMER_RESTART;
1677 	} else
1678 		return HRTIMER_NORESTART;
1679 }
1680 
1681 int kvm_create_lapic(struct kvm_vcpu *vcpu)
1682 {
1683 	struct kvm_lapic *apic;
1684 
1685 	ASSERT(vcpu != NULL);
1686 	apic_debug("apic_init %d\n", vcpu->vcpu_id);
1687 
1688 	apic = kzalloc(sizeof(*apic), GFP_KERNEL);
1689 	if (!apic)
1690 		goto nomem;
1691 
1692 	vcpu->arch.apic = apic;
1693 
1694 	apic->regs = (void *)get_zeroed_page(GFP_KERNEL);
1695 	if (!apic->regs) {
1696 		printk(KERN_ERR "malloc apic regs error for vcpu %x\n",
1697 		       vcpu->vcpu_id);
1698 		goto nomem_free_apic;
1699 	}
1700 	apic->vcpu = vcpu;
1701 
1702 	hrtimer_init(&apic->lapic_timer.timer, CLOCK_MONOTONIC,
1703 		     HRTIMER_MODE_ABS);
1704 	apic->lapic_timer.timer.function = apic_timer_fn;
1705 
1706 	/*
1707 	 * APIC is created enabled. This will prevent kvm_lapic_set_base from
1708 	 * thinking that APIC satet has changed.
1709 	 */
1710 	vcpu->arch.apic_base = MSR_IA32_APICBASE_ENABLE;
1711 	kvm_lapic_set_base(vcpu,
1712 			APIC_DEFAULT_PHYS_BASE | MSR_IA32_APICBASE_ENABLE);
1713 
1714 	static_key_slow_inc(&apic_sw_disabled.key); /* sw disabled at reset */
1715 	kvm_lapic_reset(vcpu);
1716 	kvm_iodevice_init(&apic->dev, &apic_mmio_ops);
1717 
1718 	return 0;
1719 nomem_free_apic:
1720 	kfree(apic);
1721 nomem:
1722 	return -ENOMEM;
1723 }
1724 
1725 int kvm_apic_has_interrupt(struct kvm_vcpu *vcpu)
1726 {
1727 	struct kvm_lapic *apic = vcpu->arch.apic;
1728 	int highest_irr;
1729 
1730 	if (!kvm_vcpu_has_lapic(vcpu) || !apic_enabled(apic))
1731 		return -1;
1732 
1733 	apic_update_ppr(apic);
1734 	highest_irr = apic_find_highest_irr(apic);
1735 	if ((highest_irr == -1) ||
1736 	    ((highest_irr & 0xF0) <= kvm_apic_get_reg(apic, APIC_PROCPRI)))
1737 		return -1;
1738 	return highest_irr;
1739 }
1740 
1741 int kvm_apic_accept_pic_intr(struct kvm_vcpu *vcpu)
1742 {
1743 	u32 lvt0 = kvm_apic_get_reg(vcpu->arch.apic, APIC_LVT0);
1744 	int r = 0;
1745 
1746 	if (!kvm_apic_hw_enabled(vcpu->arch.apic))
1747 		r = 1;
1748 	if ((lvt0 & APIC_LVT_MASKED) == 0 &&
1749 	    GET_APIC_DELIVERY_MODE(lvt0) == APIC_MODE_EXTINT)
1750 		r = 1;
1751 	return r;
1752 }
1753 
1754 void kvm_inject_apic_timer_irqs(struct kvm_vcpu *vcpu)
1755 {
1756 	struct kvm_lapic *apic = vcpu->arch.apic;
1757 
1758 	if (!kvm_vcpu_has_lapic(vcpu))
1759 		return;
1760 
1761 	if (atomic_read(&apic->lapic_timer.pending) > 0) {
1762 		kvm_apic_local_deliver(apic, APIC_LVTT);
1763 		if (apic_lvtt_tscdeadline(apic))
1764 			apic->lapic_timer.tscdeadline = 0;
1765 		atomic_set(&apic->lapic_timer.pending, 0);
1766 	}
1767 }
1768 
1769 int kvm_get_apic_interrupt(struct kvm_vcpu *vcpu)
1770 {
1771 	int vector = kvm_apic_has_interrupt(vcpu);
1772 	struct kvm_lapic *apic = vcpu->arch.apic;
1773 
1774 	if (vector == -1)
1775 		return -1;
1776 
1777 	/*
1778 	 * We get here even with APIC virtualization enabled, if doing
1779 	 * nested virtualization and L1 runs with the "acknowledge interrupt
1780 	 * on exit" mode.  Then we cannot inject the interrupt via RVI,
1781 	 * because the process would deliver it through the IDT.
1782 	 */
1783 
1784 	apic_set_isr(vector, apic);
1785 	apic_update_ppr(apic);
1786 	apic_clear_irr(vector, apic);
1787 	return vector;
1788 }
1789 
1790 void kvm_apic_post_state_restore(struct kvm_vcpu *vcpu,
1791 		struct kvm_lapic_state *s)
1792 {
1793 	struct kvm_lapic *apic = vcpu->arch.apic;
1794 
1795 	kvm_lapic_set_base(vcpu, vcpu->arch.apic_base);
1796 	/* set SPIV separately to get count of SW disabled APICs right */
1797 	apic_set_spiv(apic, *((u32 *)(s->regs + APIC_SPIV)));
1798 	memcpy(vcpu->arch.apic->regs, s->regs, sizeof *s);
1799 	/* call kvm_apic_set_id() to put apic into apic_map */
1800 	kvm_apic_set_id(apic, kvm_apic_id(apic));
1801 	kvm_apic_set_version(vcpu);
1802 
1803 	apic_update_ppr(apic);
1804 	hrtimer_cancel(&apic->lapic_timer.timer);
1805 	update_divide_count(apic);
1806 	start_apic_timer(apic);
1807 	apic->irr_pending = true;
1808 	apic->isr_count = kvm_x86_ops->hwapic_isr_update ?
1809 				1 : count_vectors(apic->regs + APIC_ISR);
1810 	apic->highest_isr_cache = -1;
1811 	if (kvm_x86_ops->hwapic_irr_update)
1812 		kvm_x86_ops->hwapic_irr_update(vcpu,
1813 				apic_find_highest_irr(apic));
1814 	if (unlikely(kvm_x86_ops->hwapic_isr_update))
1815 		kvm_x86_ops->hwapic_isr_update(vcpu->kvm,
1816 				apic_find_highest_isr(apic));
1817 	kvm_make_request(KVM_REQ_EVENT, vcpu);
1818 	kvm_rtc_eoi_tracking_restore_one(vcpu);
1819 }
1820 
1821 void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
1822 {
1823 	struct hrtimer *timer;
1824 
1825 	if (!kvm_vcpu_has_lapic(vcpu))
1826 		return;
1827 
1828 	timer = &vcpu->arch.apic->lapic_timer.timer;
1829 	if (hrtimer_cancel(timer))
1830 		hrtimer_start_expires(timer, HRTIMER_MODE_ABS);
1831 }
1832 
1833 /*
1834  * apic_sync_pv_eoi_from_guest - called on vmexit or cancel interrupt
1835  *
1836  * Detect whether guest triggered PV EOI since the
1837  * last entry. If yes, set EOI on guests's behalf.
1838  * Clear PV EOI in guest memory in any case.
1839  */
1840 static void apic_sync_pv_eoi_from_guest(struct kvm_vcpu *vcpu,
1841 					struct kvm_lapic *apic)
1842 {
1843 	bool pending;
1844 	int vector;
1845 	/*
1846 	 * PV EOI state is derived from KVM_APIC_PV_EOI_PENDING in host
1847 	 * and KVM_PV_EOI_ENABLED in guest memory as follows:
1848 	 *
1849 	 * KVM_APIC_PV_EOI_PENDING is unset:
1850 	 * 	-> host disabled PV EOI.
1851 	 * KVM_APIC_PV_EOI_PENDING is set, KVM_PV_EOI_ENABLED is set:
1852 	 * 	-> host enabled PV EOI, guest did not execute EOI yet.
1853 	 * KVM_APIC_PV_EOI_PENDING is set, KVM_PV_EOI_ENABLED is unset:
1854 	 * 	-> host enabled PV EOI, guest executed EOI.
1855 	 */
1856 	BUG_ON(!pv_eoi_enabled(vcpu));
1857 	pending = pv_eoi_get_pending(vcpu);
1858 	/*
1859 	 * Clear pending bit in any case: it will be set again on vmentry.
1860 	 * While this might not be ideal from performance point of view,
1861 	 * this makes sure pv eoi is only enabled when we know it's safe.
1862 	 */
1863 	pv_eoi_clr_pending(vcpu);
1864 	if (pending)
1865 		return;
1866 	vector = apic_set_eoi(apic);
1867 	trace_kvm_pv_eoi(apic, vector);
1868 }
1869 
1870 void kvm_lapic_sync_from_vapic(struct kvm_vcpu *vcpu)
1871 {
1872 	u32 data;
1873 
1874 	if (test_bit(KVM_APIC_PV_EOI_PENDING, &vcpu->arch.apic_attention))
1875 		apic_sync_pv_eoi_from_guest(vcpu, vcpu->arch.apic);
1876 
1877 	if (!test_bit(KVM_APIC_CHECK_VAPIC, &vcpu->arch.apic_attention))
1878 		return;
1879 
1880 	kvm_read_guest_cached(vcpu->kvm, &vcpu->arch.apic->vapic_cache, &data,
1881 				sizeof(u32));
1882 
1883 	apic_set_tpr(vcpu->arch.apic, data & 0xff);
1884 }
1885 
1886 /*
1887  * apic_sync_pv_eoi_to_guest - called before vmentry
1888  *
1889  * Detect whether it's safe to enable PV EOI and
1890  * if yes do so.
1891  */
1892 static void apic_sync_pv_eoi_to_guest(struct kvm_vcpu *vcpu,
1893 					struct kvm_lapic *apic)
1894 {
1895 	if (!pv_eoi_enabled(vcpu) ||
1896 	    /* IRR set or many bits in ISR: could be nested. */
1897 	    apic->irr_pending ||
1898 	    /* Cache not set: could be safe but we don't bother. */
1899 	    apic->highest_isr_cache == -1 ||
1900 	    /* Need EOI to update ioapic. */
1901 	    kvm_ioapic_handles_vector(vcpu->kvm, apic->highest_isr_cache)) {
1902 		/*
1903 		 * PV EOI was disabled by apic_sync_pv_eoi_from_guest
1904 		 * so we need not do anything here.
1905 		 */
1906 		return;
1907 	}
1908 
1909 	pv_eoi_set_pending(apic->vcpu);
1910 }
1911 
1912 void kvm_lapic_sync_to_vapic(struct kvm_vcpu *vcpu)
1913 {
1914 	u32 data, tpr;
1915 	int max_irr, max_isr;
1916 	struct kvm_lapic *apic = vcpu->arch.apic;
1917 
1918 	apic_sync_pv_eoi_to_guest(vcpu, apic);
1919 
1920 	if (!test_bit(KVM_APIC_CHECK_VAPIC, &vcpu->arch.apic_attention))
1921 		return;
1922 
1923 	tpr = kvm_apic_get_reg(apic, APIC_TASKPRI) & 0xff;
1924 	max_irr = apic_find_highest_irr(apic);
1925 	if (max_irr < 0)
1926 		max_irr = 0;
1927 	max_isr = apic_find_highest_isr(apic);
1928 	if (max_isr < 0)
1929 		max_isr = 0;
1930 	data = (tpr & 0xff) | ((max_isr & 0xf0) << 8) | (max_irr << 24);
1931 
1932 	kvm_write_guest_cached(vcpu->kvm, &vcpu->arch.apic->vapic_cache, &data,
1933 				sizeof(u32));
1934 }
1935 
1936 int kvm_lapic_set_vapic_addr(struct kvm_vcpu *vcpu, gpa_t vapic_addr)
1937 {
1938 	if (vapic_addr) {
1939 		if (kvm_gfn_to_hva_cache_init(vcpu->kvm,
1940 					&vcpu->arch.apic->vapic_cache,
1941 					vapic_addr, sizeof(u32)))
1942 			return -EINVAL;
1943 		__set_bit(KVM_APIC_CHECK_VAPIC, &vcpu->arch.apic_attention);
1944 	} else {
1945 		__clear_bit(KVM_APIC_CHECK_VAPIC, &vcpu->arch.apic_attention);
1946 	}
1947 
1948 	vcpu->arch.apic->vapic_addr = vapic_addr;
1949 	return 0;
1950 }
1951 
1952 int kvm_x2apic_msr_write(struct kvm_vcpu *vcpu, u32 msr, u64 data)
1953 {
1954 	struct kvm_lapic *apic = vcpu->arch.apic;
1955 	u32 reg = (msr - APIC_BASE_MSR) << 4;
1956 
1957 	if (!irqchip_in_kernel(vcpu->kvm) || !apic_x2apic_mode(apic))
1958 		return 1;
1959 
1960 	if (reg == APIC_ICR2)
1961 		return 1;
1962 
1963 	/* if this is ICR write vector before command */
1964 	if (reg == APIC_ICR)
1965 		apic_reg_write(apic, APIC_ICR2, (u32)(data >> 32));
1966 	return apic_reg_write(apic, reg, (u32)data);
1967 }
1968 
1969 int kvm_x2apic_msr_read(struct kvm_vcpu *vcpu, u32 msr, u64 *data)
1970 {
1971 	struct kvm_lapic *apic = vcpu->arch.apic;
1972 	u32 reg = (msr - APIC_BASE_MSR) << 4, low, high = 0;
1973 
1974 	if (!irqchip_in_kernel(vcpu->kvm) || !apic_x2apic_mode(apic))
1975 		return 1;
1976 
1977 	if (reg == APIC_DFR || reg == APIC_ICR2) {
1978 		apic_debug("KVM_APIC_READ: read x2apic reserved register %x\n",
1979 			   reg);
1980 		return 1;
1981 	}
1982 
1983 	if (apic_reg_read(apic, reg, 4, &low))
1984 		return 1;
1985 	if (reg == APIC_ICR)
1986 		apic_reg_read(apic, APIC_ICR2, 4, &high);
1987 
1988 	*data = (((u64)high) << 32) | low;
1989 
1990 	return 0;
1991 }
1992 
1993 int kvm_hv_vapic_msr_write(struct kvm_vcpu *vcpu, u32 reg, u64 data)
1994 {
1995 	struct kvm_lapic *apic = vcpu->arch.apic;
1996 
1997 	if (!kvm_vcpu_has_lapic(vcpu))
1998 		return 1;
1999 
2000 	/* if this is ICR write vector before command */
2001 	if (reg == APIC_ICR)
2002 		apic_reg_write(apic, APIC_ICR2, (u32)(data >> 32));
2003 	return apic_reg_write(apic, reg, (u32)data);
2004 }
2005 
2006 int kvm_hv_vapic_msr_read(struct kvm_vcpu *vcpu, u32 reg, u64 *data)
2007 {
2008 	struct kvm_lapic *apic = vcpu->arch.apic;
2009 	u32 low, high = 0;
2010 
2011 	if (!kvm_vcpu_has_lapic(vcpu))
2012 		return 1;
2013 
2014 	if (apic_reg_read(apic, reg, 4, &low))
2015 		return 1;
2016 	if (reg == APIC_ICR)
2017 		apic_reg_read(apic, APIC_ICR2, 4, &high);
2018 
2019 	*data = (((u64)high) << 32) | low;
2020 
2021 	return 0;
2022 }
2023 
2024 int kvm_lapic_enable_pv_eoi(struct kvm_vcpu *vcpu, u64 data)
2025 {
2026 	u64 addr = data & ~KVM_MSR_ENABLED;
2027 	if (!IS_ALIGNED(addr, 4))
2028 		return 1;
2029 
2030 	vcpu->arch.pv_eoi.msr_val = data;
2031 	if (!pv_eoi_enabled(vcpu))
2032 		return 0;
2033 	return kvm_gfn_to_hva_cache_init(vcpu->kvm, &vcpu->arch.pv_eoi.data,
2034 					 addr, sizeof(u8));
2035 }
2036 
2037 void kvm_apic_accept_events(struct kvm_vcpu *vcpu)
2038 {
2039 	struct kvm_lapic *apic = vcpu->arch.apic;
2040 	u8 sipi_vector;
2041 	unsigned long pe;
2042 
2043 	if (!kvm_vcpu_has_lapic(vcpu) || !apic->pending_events)
2044 		return;
2045 
2046 	pe = xchg(&apic->pending_events, 0);
2047 
2048 	if (test_bit(KVM_APIC_INIT, &pe)) {
2049 		kvm_lapic_reset(vcpu);
2050 		kvm_vcpu_reset(vcpu);
2051 		if (kvm_vcpu_is_bsp(apic->vcpu))
2052 			vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
2053 		else
2054 			vcpu->arch.mp_state = KVM_MP_STATE_INIT_RECEIVED;
2055 	}
2056 	if (test_bit(KVM_APIC_SIPI, &pe) &&
2057 	    vcpu->arch.mp_state == KVM_MP_STATE_INIT_RECEIVED) {
2058 		/* evaluate pending_events before reading the vector */
2059 		smp_rmb();
2060 		sipi_vector = apic->sipi_vector;
2061 		apic_debug("vcpu %d received sipi with vector # %x\n",
2062 			 vcpu->vcpu_id, sipi_vector);
2063 		kvm_vcpu_deliver_sipi_vector(vcpu, sipi_vector);
2064 		vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
2065 	}
2066 }
2067 
2068 void kvm_lapic_init(void)
2069 {
2070 	/* do not patch jump label more than once per second */
2071 	jump_label_rate_limit(&apic_hw_disabled, HZ);
2072 	jump_label_rate_limit(&apic_sw_disabled, HZ);
2073 }
2074