xref: /openbmc/linux/arch/x86/kvm/lapic.c (revision f42b3800)
1 
2 /*
3  * Local APIC virtualization
4  *
5  * Copyright (C) 2006 Qumranet, Inc.
6  * Copyright (C) 2007 Novell
7  * Copyright (C) 2007 Intel
8  *
9  * Authors:
10  *   Dor Laor <dor.laor@qumranet.com>
11  *   Gregory Haskins <ghaskins@novell.com>
12  *   Yaozu (Eddie) Dong <eddie.dong@intel.com>
13  *
14  * Based on Xen 3.1 code, Copyright (c) 2004, Intel Corporation.
15  *
16  * This work is licensed under the terms of the GNU GPL, version 2.  See
17  * the COPYING file in the top-level directory.
18  */
19 
20 #include <linux/kvm_host.h>
21 #include <linux/kvm.h>
22 #include <linux/mm.h>
23 #include <linux/highmem.h>
24 #include <linux/smp.h>
25 #include <linux/hrtimer.h>
26 #include <linux/io.h>
27 #include <linux/module.h>
28 #include <asm/processor.h>
29 #include <asm/msr.h>
30 #include <asm/page.h>
31 #include <asm/current.h>
32 #include <asm/apicdef.h>
33 #include <asm/atomic.h>
34 #include <asm/div64.h>
35 #include "irq.h"
36 
37 #define PRId64 "d"
38 #define PRIx64 "llx"
39 #define PRIu64 "u"
40 #define PRIo64 "o"
41 
42 #define APIC_BUS_CYCLE_NS 1
43 
44 /* #define apic_debug(fmt,arg...) printk(KERN_WARNING fmt,##arg) */
45 #define apic_debug(fmt, arg...)
46 
47 #define APIC_LVT_NUM			6
48 /* 14 is the version for Xeon and Pentium 8.4.8*/
49 #define APIC_VERSION			(0x14UL | ((APIC_LVT_NUM - 1) << 16))
50 #define LAPIC_MMIO_LENGTH		(1 << 12)
51 /* followed define is not in apicdef.h */
52 #define APIC_SHORT_MASK			0xc0000
53 #define APIC_DEST_NOSHORT		0x0
54 #define APIC_DEST_MASK			0x800
55 #define MAX_APIC_VECTOR			256
56 
57 #define VEC_POS(v) ((v) & (32 - 1))
58 #define REG_POS(v) (((v) >> 5) << 4)
59 
60 static inline u32 apic_get_reg(struct kvm_lapic *apic, int reg_off)
61 {
62 	return *((u32 *) (apic->regs + reg_off));
63 }
64 
65 static inline void apic_set_reg(struct kvm_lapic *apic, int reg_off, u32 val)
66 {
67 	*((u32 *) (apic->regs + reg_off)) = val;
68 }
69 
70 static inline int apic_test_and_set_vector(int vec, void *bitmap)
71 {
72 	return test_and_set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
73 }
74 
75 static inline int apic_test_and_clear_vector(int vec, void *bitmap)
76 {
77 	return test_and_clear_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
78 }
79 
80 static inline void apic_set_vector(int vec, void *bitmap)
81 {
82 	set_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
83 }
84 
85 static inline void apic_clear_vector(int vec, void *bitmap)
86 {
87 	clear_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
88 }
89 
90 static inline int apic_hw_enabled(struct kvm_lapic *apic)
91 {
92 	return (apic)->vcpu->arch.apic_base & MSR_IA32_APICBASE_ENABLE;
93 }
94 
95 static inline int  apic_sw_enabled(struct kvm_lapic *apic)
96 {
97 	return apic_get_reg(apic, APIC_SPIV) & APIC_SPIV_APIC_ENABLED;
98 }
99 
100 static inline int apic_enabled(struct kvm_lapic *apic)
101 {
102 	return apic_sw_enabled(apic) &&	apic_hw_enabled(apic);
103 }
104 
105 #define LVT_MASK	\
106 	(APIC_LVT_MASKED | APIC_SEND_PENDING | APIC_VECTOR_MASK)
107 
108 #define LINT_MASK	\
109 	(LVT_MASK | APIC_MODE_MASK | APIC_INPUT_POLARITY | \
110 	 APIC_LVT_REMOTE_IRR | APIC_LVT_LEVEL_TRIGGER)
111 
112 static inline int kvm_apic_id(struct kvm_lapic *apic)
113 {
114 	return (apic_get_reg(apic, APIC_ID) >> 24) & 0xff;
115 }
116 
117 static inline int apic_lvt_enabled(struct kvm_lapic *apic, int lvt_type)
118 {
119 	return !(apic_get_reg(apic, lvt_type) & APIC_LVT_MASKED);
120 }
121 
122 static inline int apic_lvt_vector(struct kvm_lapic *apic, int lvt_type)
123 {
124 	return apic_get_reg(apic, lvt_type) & APIC_VECTOR_MASK;
125 }
126 
127 static inline int apic_lvtt_period(struct kvm_lapic *apic)
128 {
129 	return apic_get_reg(apic, APIC_LVTT) & APIC_LVT_TIMER_PERIODIC;
130 }
131 
132 static unsigned int apic_lvt_mask[APIC_LVT_NUM] = {
133 	LVT_MASK | APIC_LVT_TIMER_PERIODIC,	/* LVTT */
134 	LVT_MASK | APIC_MODE_MASK,	/* LVTTHMR */
135 	LVT_MASK | APIC_MODE_MASK,	/* LVTPC */
136 	LINT_MASK, LINT_MASK,	/* LVT0-1 */
137 	LVT_MASK		/* LVTERR */
138 };
139 
140 static int find_highest_vector(void *bitmap)
141 {
142 	u32 *word = bitmap;
143 	int word_offset = MAX_APIC_VECTOR >> 5;
144 
145 	while ((word_offset != 0) && (word[(--word_offset) << 2] == 0))
146 		continue;
147 
148 	if (likely(!word_offset && !word[0]))
149 		return -1;
150 	else
151 		return fls(word[word_offset << 2]) - 1 + (word_offset << 5);
152 }
153 
154 static inline int apic_test_and_set_irr(int vec, struct kvm_lapic *apic)
155 {
156 	return apic_test_and_set_vector(vec, apic->regs + APIC_IRR);
157 }
158 
159 static inline void apic_clear_irr(int vec, struct kvm_lapic *apic)
160 {
161 	apic_clear_vector(vec, apic->regs + APIC_IRR);
162 }
163 
164 static inline int apic_find_highest_irr(struct kvm_lapic *apic)
165 {
166 	int result;
167 
168 	result = find_highest_vector(apic->regs + APIC_IRR);
169 	ASSERT(result == -1 || result >= 16);
170 
171 	return result;
172 }
173 
174 int kvm_lapic_find_highest_irr(struct kvm_vcpu *vcpu)
175 {
176 	struct kvm_lapic *apic = vcpu->arch.apic;
177 	int highest_irr;
178 
179 	if (!apic)
180 		return 0;
181 	highest_irr = apic_find_highest_irr(apic);
182 
183 	return highest_irr;
184 }
185 EXPORT_SYMBOL_GPL(kvm_lapic_find_highest_irr);
186 
187 int kvm_apic_set_irq(struct kvm_vcpu *vcpu, u8 vec, u8 trig)
188 {
189 	struct kvm_lapic *apic = vcpu->arch.apic;
190 
191 	if (!apic_test_and_set_irr(vec, apic)) {
192 		/* a new pending irq is set in IRR */
193 		if (trig)
194 			apic_set_vector(vec, apic->regs + APIC_TMR);
195 		else
196 			apic_clear_vector(vec, apic->regs + APIC_TMR);
197 		kvm_vcpu_kick(apic->vcpu);
198 		return 1;
199 	}
200 	return 0;
201 }
202 
203 static inline int apic_find_highest_isr(struct kvm_lapic *apic)
204 {
205 	int result;
206 
207 	result = find_highest_vector(apic->regs + APIC_ISR);
208 	ASSERT(result == -1 || result >= 16);
209 
210 	return result;
211 }
212 
213 static void apic_update_ppr(struct kvm_lapic *apic)
214 {
215 	u32 tpr, isrv, ppr;
216 	int isr;
217 
218 	tpr = apic_get_reg(apic, APIC_TASKPRI);
219 	isr = apic_find_highest_isr(apic);
220 	isrv = (isr != -1) ? isr : 0;
221 
222 	if ((tpr & 0xf0) >= (isrv & 0xf0))
223 		ppr = tpr & 0xff;
224 	else
225 		ppr = isrv & 0xf0;
226 
227 	apic_debug("vlapic %p, ppr 0x%x, isr 0x%x, isrv 0x%x",
228 		   apic, ppr, isr, isrv);
229 
230 	apic_set_reg(apic, APIC_PROCPRI, ppr);
231 }
232 
233 static void apic_set_tpr(struct kvm_lapic *apic, u32 tpr)
234 {
235 	apic_set_reg(apic, APIC_TASKPRI, tpr);
236 	apic_update_ppr(apic);
237 }
238 
239 int kvm_apic_match_physical_addr(struct kvm_lapic *apic, u16 dest)
240 {
241 	return kvm_apic_id(apic) == dest;
242 }
243 
244 int kvm_apic_match_logical_addr(struct kvm_lapic *apic, u8 mda)
245 {
246 	int result = 0;
247 	u8 logical_id;
248 
249 	logical_id = GET_APIC_LOGICAL_ID(apic_get_reg(apic, APIC_LDR));
250 
251 	switch (apic_get_reg(apic, APIC_DFR)) {
252 	case APIC_DFR_FLAT:
253 		if (logical_id & mda)
254 			result = 1;
255 		break;
256 	case APIC_DFR_CLUSTER:
257 		if (((logical_id >> 4) == (mda >> 0x4))
258 		    && (logical_id & mda & 0xf))
259 			result = 1;
260 		break;
261 	default:
262 		printk(KERN_WARNING "Bad DFR vcpu %d: %08x\n",
263 		       apic->vcpu->vcpu_id, apic_get_reg(apic, APIC_DFR));
264 		break;
265 	}
266 
267 	return result;
268 }
269 
270 static int apic_match_dest(struct kvm_vcpu *vcpu, struct kvm_lapic *source,
271 			   int short_hand, int dest, int dest_mode)
272 {
273 	int result = 0;
274 	struct kvm_lapic *target = vcpu->arch.apic;
275 
276 	apic_debug("target %p, source %p, dest 0x%x, "
277 		   "dest_mode 0x%x, short_hand 0x%x",
278 		   target, source, dest, dest_mode, short_hand);
279 
280 	ASSERT(!target);
281 	switch (short_hand) {
282 	case APIC_DEST_NOSHORT:
283 		if (dest_mode == 0) {
284 			/* Physical mode. */
285 			if ((dest == 0xFF) || (dest == kvm_apic_id(target)))
286 				result = 1;
287 		} else
288 			/* Logical mode. */
289 			result = kvm_apic_match_logical_addr(target, dest);
290 		break;
291 	case APIC_DEST_SELF:
292 		if (target == source)
293 			result = 1;
294 		break;
295 	case APIC_DEST_ALLINC:
296 		result = 1;
297 		break;
298 	case APIC_DEST_ALLBUT:
299 		if (target != source)
300 			result = 1;
301 		break;
302 	default:
303 		printk(KERN_WARNING "Bad dest shorthand value %x\n",
304 		       short_hand);
305 		break;
306 	}
307 
308 	return result;
309 }
310 
311 /*
312  * Add a pending IRQ into lapic.
313  * Return 1 if successfully added and 0 if discarded.
314  */
315 static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode,
316 			     int vector, int level, int trig_mode)
317 {
318 	int orig_irr, result = 0;
319 	struct kvm_vcpu *vcpu = apic->vcpu;
320 
321 	switch (delivery_mode) {
322 	case APIC_DM_FIXED:
323 	case APIC_DM_LOWEST:
324 		/* FIXME add logic for vcpu on reset */
325 		if (unlikely(!apic_enabled(apic)))
326 			break;
327 
328 		orig_irr = apic_test_and_set_irr(vector, apic);
329 		if (orig_irr && trig_mode) {
330 			apic_debug("level trig mode repeatedly for vector %d",
331 				   vector);
332 			break;
333 		}
334 
335 		if (trig_mode) {
336 			apic_debug("level trig mode for vector %d", vector);
337 			apic_set_vector(vector, apic->regs + APIC_TMR);
338 		} else
339 			apic_clear_vector(vector, apic->regs + APIC_TMR);
340 
341 		if (vcpu->arch.mp_state == VCPU_MP_STATE_RUNNABLE)
342 			kvm_vcpu_kick(vcpu);
343 		else if (vcpu->arch.mp_state == VCPU_MP_STATE_HALTED) {
344 			vcpu->arch.mp_state = VCPU_MP_STATE_RUNNABLE;
345 			if (waitqueue_active(&vcpu->wq))
346 				wake_up_interruptible(&vcpu->wq);
347 		}
348 
349 		result = (orig_irr == 0);
350 		break;
351 
352 	case APIC_DM_REMRD:
353 		printk(KERN_DEBUG "Ignoring delivery mode 3\n");
354 		break;
355 
356 	case APIC_DM_SMI:
357 		printk(KERN_DEBUG "Ignoring guest SMI\n");
358 		break;
359 	case APIC_DM_NMI:
360 		printk(KERN_DEBUG "Ignoring guest NMI\n");
361 		break;
362 
363 	case APIC_DM_INIT:
364 		if (level) {
365 			if (vcpu->arch.mp_state == VCPU_MP_STATE_RUNNABLE)
366 				printk(KERN_DEBUG
367 				       "INIT on a runnable vcpu %d\n",
368 				       vcpu->vcpu_id);
369 			vcpu->arch.mp_state = VCPU_MP_STATE_INIT_RECEIVED;
370 			kvm_vcpu_kick(vcpu);
371 		} else {
372 			printk(KERN_DEBUG
373 			       "Ignoring de-assert INIT to vcpu %d\n",
374 			       vcpu->vcpu_id);
375 		}
376 
377 		break;
378 
379 	case APIC_DM_STARTUP:
380 		printk(KERN_DEBUG "SIPI to vcpu %d vector 0x%02x\n",
381 		       vcpu->vcpu_id, vector);
382 		if (vcpu->arch.mp_state == VCPU_MP_STATE_INIT_RECEIVED) {
383 			vcpu->arch.sipi_vector = vector;
384 			vcpu->arch.mp_state = VCPU_MP_STATE_SIPI_RECEIVED;
385 			if (waitqueue_active(&vcpu->wq))
386 				wake_up_interruptible(&vcpu->wq);
387 		}
388 		break;
389 
390 	default:
391 		printk(KERN_ERR "TODO: unsupported delivery mode %x\n",
392 		       delivery_mode);
393 		break;
394 	}
395 	return result;
396 }
397 
398 static struct kvm_lapic *kvm_apic_round_robin(struct kvm *kvm, u8 vector,
399 				       unsigned long bitmap)
400 {
401 	int last;
402 	int next;
403 	struct kvm_lapic *apic = NULL;
404 
405 	last = kvm->arch.round_robin_prev_vcpu;
406 	next = last;
407 
408 	do {
409 		if (++next == KVM_MAX_VCPUS)
410 			next = 0;
411 		if (kvm->vcpus[next] == NULL || !test_bit(next, &bitmap))
412 			continue;
413 		apic = kvm->vcpus[next]->arch.apic;
414 		if (apic && apic_enabled(apic))
415 			break;
416 		apic = NULL;
417 	} while (next != last);
418 	kvm->arch.round_robin_prev_vcpu = next;
419 
420 	if (!apic)
421 		printk(KERN_DEBUG "vcpu not ready for apic_round_robin\n");
422 
423 	return apic;
424 }
425 
426 struct kvm_vcpu *kvm_get_lowest_prio_vcpu(struct kvm *kvm, u8 vector,
427 		unsigned long bitmap)
428 {
429 	struct kvm_lapic *apic;
430 
431 	apic = kvm_apic_round_robin(kvm, vector, bitmap);
432 	if (apic)
433 		return apic->vcpu;
434 	return NULL;
435 }
436 
437 static void apic_set_eoi(struct kvm_lapic *apic)
438 {
439 	int vector = apic_find_highest_isr(apic);
440 
441 	/*
442 	 * Not every write EOI will has corresponding ISR,
443 	 * one example is when Kernel check timer on setup_IO_APIC
444 	 */
445 	if (vector == -1)
446 		return;
447 
448 	apic_clear_vector(vector, apic->regs + APIC_ISR);
449 	apic_update_ppr(apic);
450 
451 	if (apic_test_and_clear_vector(vector, apic->regs + APIC_TMR))
452 		kvm_ioapic_update_eoi(apic->vcpu->kvm, vector);
453 }
454 
455 static void apic_send_ipi(struct kvm_lapic *apic)
456 {
457 	u32 icr_low = apic_get_reg(apic, APIC_ICR);
458 	u32 icr_high = apic_get_reg(apic, APIC_ICR2);
459 
460 	unsigned int dest = GET_APIC_DEST_FIELD(icr_high);
461 	unsigned int short_hand = icr_low & APIC_SHORT_MASK;
462 	unsigned int trig_mode = icr_low & APIC_INT_LEVELTRIG;
463 	unsigned int level = icr_low & APIC_INT_ASSERT;
464 	unsigned int dest_mode = icr_low & APIC_DEST_MASK;
465 	unsigned int delivery_mode = icr_low & APIC_MODE_MASK;
466 	unsigned int vector = icr_low & APIC_VECTOR_MASK;
467 
468 	struct kvm_vcpu *target;
469 	struct kvm_vcpu *vcpu;
470 	unsigned long lpr_map = 0;
471 	int i;
472 
473 	apic_debug("icr_high 0x%x, icr_low 0x%x, "
474 		   "short_hand 0x%x, dest 0x%x, trig_mode 0x%x, level 0x%x, "
475 		   "dest_mode 0x%x, delivery_mode 0x%x, vector 0x%x\n",
476 		   icr_high, icr_low, short_hand, dest,
477 		   trig_mode, level, dest_mode, delivery_mode, vector);
478 
479 	for (i = 0; i < KVM_MAX_VCPUS; i++) {
480 		vcpu = apic->vcpu->kvm->vcpus[i];
481 		if (!vcpu)
482 			continue;
483 
484 		if (vcpu->arch.apic &&
485 		    apic_match_dest(vcpu, apic, short_hand, dest, dest_mode)) {
486 			if (delivery_mode == APIC_DM_LOWEST)
487 				set_bit(vcpu->vcpu_id, &lpr_map);
488 			else
489 				__apic_accept_irq(vcpu->arch.apic, delivery_mode,
490 						  vector, level, trig_mode);
491 		}
492 	}
493 
494 	if (delivery_mode == APIC_DM_LOWEST) {
495 		target = kvm_get_lowest_prio_vcpu(vcpu->kvm, vector, lpr_map);
496 		if (target != NULL)
497 			__apic_accept_irq(target->arch.apic, delivery_mode,
498 					  vector, level, trig_mode);
499 	}
500 }
501 
502 static u32 apic_get_tmcct(struct kvm_lapic *apic)
503 {
504 	u64 counter_passed;
505 	ktime_t passed, now;
506 	u32 tmcct;
507 
508 	ASSERT(apic != NULL);
509 
510 	now = apic->timer.dev.base->get_time();
511 	tmcct = apic_get_reg(apic, APIC_TMICT);
512 
513 	/* if initial count is 0, current count should also be 0 */
514 	if (tmcct == 0)
515 		return 0;
516 
517 	if (unlikely(ktime_to_ns(now) <=
518 		ktime_to_ns(apic->timer.last_update))) {
519 		/* Wrap around */
520 		passed = ktime_add(( {
521 				    (ktime_t) {
522 				    .tv64 = KTIME_MAX -
523 				    (apic->timer.last_update).tv64}; }
524 				   ), now);
525 		apic_debug("time elapsed\n");
526 	} else
527 		passed = ktime_sub(now, apic->timer.last_update);
528 
529 	counter_passed = div64_64(ktime_to_ns(passed),
530 				  (APIC_BUS_CYCLE_NS * apic->timer.divide_count));
531 
532 	if (counter_passed > tmcct) {
533 		if (unlikely(!apic_lvtt_period(apic))) {
534 			/* one-shot timers stick at 0 until reset */
535 			tmcct = 0;
536 		} else {
537 			/*
538 			 * periodic timers reset to APIC_TMICT when they
539 			 * hit 0. The while loop simulates this happening N
540 			 * times. (counter_passed %= tmcct) would also work,
541 			 * but might be slower or not work on 32-bit??
542 			 */
543 			while (counter_passed > tmcct)
544 				counter_passed -= tmcct;
545 			tmcct -= counter_passed;
546 		}
547 	} else {
548 		tmcct -= counter_passed;
549 	}
550 
551 	return tmcct;
552 }
553 
554 static void __report_tpr_access(struct kvm_lapic *apic, bool write)
555 {
556 	struct kvm_vcpu *vcpu = apic->vcpu;
557 	struct kvm_run *run = vcpu->run;
558 
559 	set_bit(KVM_REQ_REPORT_TPR_ACCESS, &vcpu->requests);
560 	kvm_x86_ops->cache_regs(vcpu);
561 	run->tpr_access.rip = vcpu->arch.rip;
562 	run->tpr_access.is_write = write;
563 }
564 
565 static inline void report_tpr_access(struct kvm_lapic *apic, bool write)
566 {
567 	if (apic->vcpu->arch.tpr_access_reporting)
568 		__report_tpr_access(apic, write);
569 }
570 
571 static u32 __apic_read(struct kvm_lapic *apic, unsigned int offset)
572 {
573 	u32 val = 0;
574 
575 	if (offset >= LAPIC_MMIO_LENGTH)
576 		return 0;
577 
578 	switch (offset) {
579 	case APIC_ARBPRI:
580 		printk(KERN_WARNING "Access APIC ARBPRI register "
581 		       "which is for P6\n");
582 		break;
583 
584 	case APIC_TMCCT:	/* Timer CCR */
585 		val = apic_get_tmcct(apic);
586 		break;
587 
588 	case APIC_TASKPRI:
589 		report_tpr_access(apic, false);
590 		/* fall thru */
591 	default:
592 		apic_update_ppr(apic);
593 		val = apic_get_reg(apic, offset);
594 		break;
595 	}
596 
597 	return val;
598 }
599 
600 static void apic_mmio_read(struct kvm_io_device *this,
601 			   gpa_t address, int len, void *data)
602 {
603 	struct kvm_lapic *apic = (struct kvm_lapic *)this->private;
604 	unsigned int offset = address - apic->base_address;
605 	unsigned char alignment = offset & 0xf;
606 	u32 result;
607 
608 	if ((alignment + len) > 4) {
609 		printk(KERN_ERR "KVM_APIC_READ: alignment error %lx %d",
610 		       (unsigned long)address, len);
611 		return;
612 	}
613 	result = __apic_read(apic, offset & ~0xf);
614 
615 	switch (len) {
616 	case 1:
617 	case 2:
618 	case 4:
619 		memcpy(data, (char *)&result + alignment, len);
620 		break;
621 	default:
622 		printk(KERN_ERR "Local APIC read with len = %x, "
623 		       "should be 1,2, or 4 instead\n", len);
624 		break;
625 	}
626 }
627 
628 static void update_divide_count(struct kvm_lapic *apic)
629 {
630 	u32 tmp1, tmp2, tdcr;
631 
632 	tdcr = apic_get_reg(apic, APIC_TDCR);
633 	tmp1 = tdcr & 0xf;
634 	tmp2 = ((tmp1 & 0x3) | ((tmp1 & 0x8) >> 1)) + 1;
635 	apic->timer.divide_count = 0x1 << (tmp2 & 0x7);
636 
637 	apic_debug("timer divide count is 0x%x\n",
638 				   apic->timer.divide_count);
639 }
640 
641 static void start_apic_timer(struct kvm_lapic *apic)
642 {
643 	ktime_t now = apic->timer.dev.base->get_time();
644 
645 	apic->timer.last_update = now;
646 
647 	apic->timer.period = apic_get_reg(apic, APIC_TMICT) *
648 		    APIC_BUS_CYCLE_NS * apic->timer.divide_count;
649 	atomic_set(&apic->timer.pending, 0);
650 
651 	if (!apic->timer.period)
652 		return;
653 
654 	hrtimer_start(&apic->timer.dev,
655 		      ktime_add_ns(now, apic->timer.period),
656 		      HRTIMER_MODE_ABS);
657 
658 	apic_debug("%s: bus cycle is %" PRId64 "ns, now 0x%016"
659 			   PRIx64 ", "
660 			   "timer initial count 0x%x, period %lldns, "
661 			   "expire @ 0x%016" PRIx64 ".\n", __FUNCTION__,
662 			   APIC_BUS_CYCLE_NS, ktime_to_ns(now),
663 			   apic_get_reg(apic, APIC_TMICT),
664 			   apic->timer.period,
665 			   ktime_to_ns(ktime_add_ns(now,
666 					apic->timer.period)));
667 }
668 
669 static void apic_mmio_write(struct kvm_io_device *this,
670 			    gpa_t address, int len, const void *data)
671 {
672 	struct kvm_lapic *apic = (struct kvm_lapic *)this->private;
673 	unsigned int offset = address - apic->base_address;
674 	unsigned char alignment = offset & 0xf;
675 	u32 val;
676 
677 	/*
678 	 * APIC register must be aligned on 128-bits boundary.
679 	 * 32/64/128 bits registers must be accessed thru 32 bits.
680 	 * Refer SDM 8.4.1
681 	 */
682 	if (len != 4 || alignment) {
683 		if (printk_ratelimit())
684 			printk(KERN_ERR "apic write: bad size=%d %lx\n",
685 			       len, (long)address);
686 		return;
687 	}
688 
689 	val = *(u32 *) data;
690 
691 	/* too common printing */
692 	if (offset != APIC_EOI)
693 		apic_debug("%s: offset 0x%x with length 0x%x, and value is "
694 			   "0x%x\n", __FUNCTION__, offset, len, val);
695 
696 	offset &= 0xff0;
697 
698 	switch (offset) {
699 	case APIC_ID:		/* Local APIC ID */
700 		apic_set_reg(apic, APIC_ID, val);
701 		break;
702 
703 	case APIC_TASKPRI:
704 		report_tpr_access(apic, true);
705 		apic_set_tpr(apic, val & 0xff);
706 		break;
707 
708 	case APIC_EOI:
709 		apic_set_eoi(apic);
710 		break;
711 
712 	case APIC_LDR:
713 		apic_set_reg(apic, APIC_LDR, val & APIC_LDR_MASK);
714 		break;
715 
716 	case APIC_DFR:
717 		apic_set_reg(apic, APIC_DFR, val | 0x0FFFFFFF);
718 		break;
719 
720 	case APIC_SPIV:
721 		apic_set_reg(apic, APIC_SPIV, val & 0x3ff);
722 		if (!(val & APIC_SPIV_APIC_ENABLED)) {
723 			int i;
724 			u32 lvt_val;
725 
726 			for (i = 0; i < APIC_LVT_NUM; i++) {
727 				lvt_val = apic_get_reg(apic,
728 						       APIC_LVTT + 0x10 * i);
729 				apic_set_reg(apic, APIC_LVTT + 0x10 * i,
730 					     lvt_val | APIC_LVT_MASKED);
731 			}
732 			atomic_set(&apic->timer.pending, 0);
733 
734 		}
735 		break;
736 
737 	case APIC_ICR:
738 		/* No delay here, so we always clear the pending bit */
739 		apic_set_reg(apic, APIC_ICR, val & ~(1 << 12));
740 		apic_send_ipi(apic);
741 		break;
742 
743 	case APIC_ICR2:
744 		apic_set_reg(apic, APIC_ICR2, val & 0xff000000);
745 		break;
746 
747 	case APIC_LVTT:
748 	case APIC_LVTTHMR:
749 	case APIC_LVTPC:
750 	case APIC_LVT0:
751 	case APIC_LVT1:
752 	case APIC_LVTERR:
753 		/* TODO: Check vector */
754 		if (!apic_sw_enabled(apic))
755 			val |= APIC_LVT_MASKED;
756 
757 		val &= apic_lvt_mask[(offset - APIC_LVTT) >> 4];
758 		apic_set_reg(apic, offset, val);
759 
760 		break;
761 
762 	case APIC_TMICT:
763 		hrtimer_cancel(&apic->timer.dev);
764 		apic_set_reg(apic, APIC_TMICT, val);
765 		start_apic_timer(apic);
766 		return;
767 
768 	case APIC_TDCR:
769 		if (val & 4)
770 			printk(KERN_ERR "KVM_WRITE:TDCR %x\n", val);
771 		apic_set_reg(apic, APIC_TDCR, val);
772 		update_divide_count(apic);
773 		break;
774 
775 	default:
776 		apic_debug("Local APIC Write to read-only register %x\n",
777 			   offset);
778 		break;
779 	}
780 
781 }
782 
783 static int apic_mmio_range(struct kvm_io_device *this, gpa_t addr)
784 {
785 	struct kvm_lapic *apic = (struct kvm_lapic *)this->private;
786 	int ret = 0;
787 
788 
789 	if (apic_hw_enabled(apic) &&
790 	    (addr >= apic->base_address) &&
791 	    (addr < (apic->base_address + LAPIC_MMIO_LENGTH)))
792 		ret = 1;
793 
794 	return ret;
795 }
796 
797 void kvm_free_lapic(struct kvm_vcpu *vcpu)
798 {
799 	if (!vcpu->arch.apic)
800 		return;
801 
802 	hrtimer_cancel(&vcpu->arch.apic->timer.dev);
803 
804 	if (vcpu->arch.apic->regs_page)
805 		__free_page(vcpu->arch.apic->regs_page);
806 
807 	kfree(vcpu->arch.apic);
808 }
809 
810 /*
811  *----------------------------------------------------------------------
812  * LAPIC interface
813  *----------------------------------------------------------------------
814  */
815 
816 void kvm_lapic_set_tpr(struct kvm_vcpu *vcpu, unsigned long cr8)
817 {
818 	struct kvm_lapic *apic = vcpu->arch.apic;
819 
820 	if (!apic)
821 		return;
822 	apic_set_tpr(apic, ((cr8 & 0x0f) << 4)
823 		     | (apic_get_reg(apic, APIC_TASKPRI) & 4));
824 }
825 
826 u64 kvm_lapic_get_cr8(struct kvm_vcpu *vcpu)
827 {
828 	struct kvm_lapic *apic = vcpu->arch.apic;
829 	u64 tpr;
830 
831 	if (!apic)
832 		return 0;
833 	tpr = (u64) apic_get_reg(apic, APIC_TASKPRI);
834 
835 	return (tpr & 0xf0) >> 4;
836 }
837 EXPORT_SYMBOL_GPL(kvm_lapic_get_cr8);
838 
839 void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value)
840 {
841 	struct kvm_lapic *apic = vcpu->arch.apic;
842 
843 	if (!apic) {
844 		value |= MSR_IA32_APICBASE_BSP;
845 		vcpu->arch.apic_base = value;
846 		return;
847 	}
848 	if (apic->vcpu->vcpu_id)
849 		value &= ~MSR_IA32_APICBASE_BSP;
850 
851 	vcpu->arch.apic_base = value;
852 	apic->base_address = apic->vcpu->arch.apic_base &
853 			     MSR_IA32_APICBASE_BASE;
854 
855 	/* with FSB delivery interrupt, we can restart APIC functionality */
856 	apic_debug("apic base msr is 0x%016" PRIx64 ", and base address is "
857 		   "0x%lx.\n", apic->vcpu->arch.apic_base, apic->base_address);
858 
859 }
860 
861 u64 kvm_lapic_get_base(struct kvm_vcpu *vcpu)
862 {
863 	return vcpu->arch.apic_base;
864 }
865 EXPORT_SYMBOL_GPL(kvm_lapic_get_base);
866 
867 void kvm_lapic_reset(struct kvm_vcpu *vcpu)
868 {
869 	struct kvm_lapic *apic;
870 	int i;
871 
872 	apic_debug("%s\n", __FUNCTION__);
873 
874 	ASSERT(vcpu);
875 	apic = vcpu->arch.apic;
876 	ASSERT(apic != NULL);
877 
878 	/* Stop the timer in case it's a reset to an active apic */
879 	hrtimer_cancel(&apic->timer.dev);
880 
881 	apic_set_reg(apic, APIC_ID, vcpu->vcpu_id << 24);
882 	apic_set_reg(apic, APIC_LVR, APIC_VERSION);
883 
884 	for (i = 0; i < APIC_LVT_NUM; i++)
885 		apic_set_reg(apic, APIC_LVTT + 0x10 * i, APIC_LVT_MASKED);
886 	apic_set_reg(apic, APIC_LVT0,
887 		     SET_APIC_DELIVERY_MODE(0, APIC_MODE_EXTINT));
888 
889 	apic_set_reg(apic, APIC_DFR, 0xffffffffU);
890 	apic_set_reg(apic, APIC_SPIV, 0xff);
891 	apic_set_reg(apic, APIC_TASKPRI, 0);
892 	apic_set_reg(apic, APIC_LDR, 0);
893 	apic_set_reg(apic, APIC_ESR, 0);
894 	apic_set_reg(apic, APIC_ICR, 0);
895 	apic_set_reg(apic, APIC_ICR2, 0);
896 	apic_set_reg(apic, APIC_TDCR, 0);
897 	apic_set_reg(apic, APIC_TMICT, 0);
898 	for (i = 0; i < 8; i++) {
899 		apic_set_reg(apic, APIC_IRR + 0x10 * i, 0);
900 		apic_set_reg(apic, APIC_ISR + 0x10 * i, 0);
901 		apic_set_reg(apic, APIC_TMR + 0x10 * i, 0);
902 	}
903 	update_divide_count(apic);
904 	atomic_set(&apic->timer.pending, 0);
905 	if (vcpu->vcpu_id == 0)
906 		vcpu->arch.apic_base |= MSR_IA32_APICBASE_BSP;
907 	apic_update_ppr(apic);
908 
909 	apic_debug(KERN_INFO "%s: vcpu=%p, id=%d, base_msr="
910 		   "0x%016" PRIx64 ", base_address=0x%0lx.\n", __FUNCTION__,
911 		   vcpu, kvm_apic_id(apic),
912 		   vcpu->arch.apic_base, apic->base_address);
913 }
914 EXPORT_SYMBOL_GPL(kvm_lapic_reset);
915 
916 int kvm_lapic_enabled(struct kvm_vcpu *vcpu)
917 {
918 	struct kvm_lapic *apic = vcpu->arch.apic;
919 	int ret = 0;
920 
921 	if (!apic)
922 		return 0;
923 	ret = apic_enabled(apic);
924 
925 	return ret;
926 }
927 EXPORT_SYMBOL_GPL(kvm_lapic_enabled);
928 
929 /*
930  *----------------------------------------------------------------------
931  * timer interface
932  *----------------------------------------------------------------------
933  */
934 
935 /* TODO: make sure __apic_timer_fn runs in current pCPU */
936 static int __apic_timer_fn(struct kvm_lapic *apic)
937 {
938 	int result = 0;
939 	wait_queue_head_t *q = &apic->vcpu->wq;
940 
941 	atomic_inc(&apic->timer.pending);
942 	if (waitqueue_active(q)) {
943 		apic->vcpu->arch.mp_state = VCPU_MP_STATE_RUNNABLE;
944 		wake_up_interruptible(q);
945 	}
946 	if (apic_lvtt_period(apic)) {
947 		result = 1;
948 		apic->timer.dev.expires = ktime_add_ns(
949 					apic->timer.dev.expires,
950 					apic->timer.period);
951 	}
952 	return result;
953 }
954 
955 static int __inject_apic_timer_irq(struct kvm_lapic *apic)
956 {
957 	int vector;
958 
959 	vector = apic_lvt_vector(apic, APIC_LVTT);
960 	return __apic_accept_irq(apic, APIC_DM_FIXED, vector, 1, 0);
961 }
962 
963 static enum hrtimer_restart apic_timer_fn(struct hrtimer *data)
964 {
965 	struct kvm_lapic *apic;
966 	int restart_timer = 0;
967 
968 	apic = container_of(data, struct kvm_lapic, timer.dev);
969 
970 	restart_timer = __apic_timer_fn(apic);
971 
972 	if (restart_timer)
973 		return HRTIMER_RESTART;
974 	else
975 		return HRTIMER_NORESTART;
976 }
977 
978 int kvm_create_lapic(struct kvm_vcpu *vcpu)
979 {
980 	struct kvm_lapic *apic;
981 
982 	ASSERT(vcpu != NULL);
983 	apic_debug("apic_init %d\n", vcpu->vcpu_id);
984 
985 	apic = kzalloc(sizeof(*apic), GFP_KERNEL);
986 	if (!apic)
987 		goto nomem;
988 
989 	vcpu->arch.apic = apic;
990 
991 	apic->regs_page = alloc_page(GFP_KERNEL);
992 	if (apic->regs_page == NULL) {
993 		printk(KERN_ERR "malloc apic regs error for vcpu %x\n",
994 		       vcpu->vcpu_id);
995 		goto nomem_free_apic;
996 	}
997 	apic->regs = page_address(apic->regs_page);
998 	memset(apic->regs, 0, PAGE_SIZE);
999 	apic->vcpu = vcpu;
1000 
1001 	hrtimer_init(&apic->timer.dev, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
1002 	apic->timer.dev.function = apic_timer_fn;
1003 	apic->base_address = APIC_DEFAULT_PHYS_BASE;
1004 	vcpu->arch.apic_base = APIC_DEFAULT_PHYS_BASE;
1005 
1006 	kvm_lapic_reset(vcpu);
1007 	apic->dev.read = apic_mmio_read;
1008 	apic->dev.write = apic_mmio_write;
1009 	apic->dev.in_range = apic_mmio_range;
1010 	apic->dev.private = apic;
1011 
1012 	return 0;
1013 nomem_free_apic:
1014 	kfree(apic);
1015 nomem:
1016 	return -ENOMEM;
1017 }
1018 EXPORT_SYMBOL_GPL(kvm_create_lapic);
1019 
1020 int kvm_apic_has_interrupt(struct kvm_vcpu *vcpu)
1021 {
1022 	struct kvm_lapic *apic = vcpu->arch.apic;
1023 	int highest_irr;
1024 
1025 	if (!apic || !apic_enabled(apic))
1026 		return -1;
1027 
1028 	apic_update_ppr(apic);
1029 	highest_irr = apic_find_highest_irr(apic);
1030 	if ((highest_irr == -1) ||
1031 	    ((highest_irr & 0xF0) <= apic_get_reg(apic, APIC_PROCPRI)))
1032 		return -1;
1033 	return highest_irr;
1034 }
1035 
1036 int kvm_apic_accept_pic_intr(struct kvm_vcpu *vcpu)
1037 {
1038 	u32 lvt0 = apic_get_reg(vcpu->arch.apic, APIC_LVT0);
1039 	int r = 0;
1040 
1041 	if (vcpu->vcpu_id == 0) {
1042 		if (!apic_hw_enabled(vcpu->arch.apic))
1043 			r = 1;
1044 		if ((lvt0 & APIC_LVT_MASKED) == 0 &&
1045 		    GET_APIC_DELIVERY_MODE(lvt0) == APIC_MODE_EXTINT)
1046 			r = 1;
1047 	}
1048 	return r;
1049 }
1050 
1051 void kvm_inject_apic_timer_irqs(struct kvm_vcpu *vcpu)
1052 {
1053 	struct kvm_lapic *apic = vcpu->arch.apic;
1054 
1055 	if (apic && apic_lvt_enabled(apic, APIC_LVTT) &&
1056 		atomic_read(&apic->timer.pending) > 0) {
1057 		if (__inject_apic_timer_irq(apic))
1058 			atomic_dec(&apic->timer.pending);
1059 	}
1060 }
1061 
1062 void kvm_apic_timer_intr_post(struct kvm_vcpu *vcpu, int vec)
1063 {
1064 	struct kvm_lapic *apic = vcpu->arch.apic;
1065 
1066 	if (apic && apic_lvt_vector(apic, APIC_LVTT) == vec)
1067 		apic->timer.last_update = ktime_add_ns(
1068 				apic->timer.last_update,
1069 				apic->timer.period);
1070 }
1071 
1072 int kvm_get_apic_interrupt(struct kvm_vcpu *vcpu)
1073 {
1074 	int vector = kvm_apic_has_interrupt(vcpu);
1075 	struct kvm_lapic *apic = vcpu->arch.apic;
1076 
1077 	if (vector == -1)
1078 		return -1;
1079 
1080 	apic_set_vector(vector, apic->regs + APIC_ISR);
1081 	apic_update_ppr(apic);
1082 	apic_clear_irr(vector, apic);
1083 	return vector;
1084 }
1085 
1086 void kvm_apic_post_state_restore(struct kvm_vcpu *vcpu)
1087 {
1088 	struct kvm_lapic *apic = vcpu->arch.apic;
1089 
1090 	apic->base_address = vcpu->arch.apic_base &
1091 			     MSR_IA32_APICBASE_BASE;
1092 	apic_set_reg(apic, APIC_LVR, APIC_VERSION);
1093 	apic_update_ppr(apic);
1094 	hrtimer_cancel(&apic->timer.dev);
1095 	update_divide_count(apic);
1096 	start_apic_timer(apic);
1097 }
1098 
1099 void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
1100 {
1101 	struct kvm_lapic *apic = vcpu->arch.apic;
1102 	struct hrtimer *timer;
1103 
1104 	if (!apic)
1105 		return;
1106 
1107 	timer = &apic->timer.dev;
1108 	if (hrtimer_cancel(timer))
1109 		hrtimer_start(timer, timer->expires, HRTIMER_MODE_ABS);
1110 }
1111 
1112 void kvm_lapic_sync_from_vapic(struct kvm_vcpu *vcpu)
1113 {
1114 	u32 data;
1115 	void *vapic;
1116 
1117 	if (!irqchip_in_kernel(vcpu->kvm) || !vcpu->arch.apic->vapic_addr)
1118 		return;
1119 
1120 	vapic = kmap_atomic(vcpu->arch.apic->vapic_page, KM_USER0);
1121 	data = *(u32 *)(vapic + offset_in_page(vcpu->arch.apic->vapic_addr));
1122 	kunmap_atomic(vapic, KM_USER0);
1123 
1124 	apic_set_tpr(vcpu->arch.apic, data & 0xff);
1125 }
1126 
1127 void kvm_lapic_sync_to_vapic(struct kvm_vcpu *vcpu)
1128 {
1129 	u32 data, tpr;
1130 	int max_irr, max_isr;
1131 	struct kvm_lapic *apic;
1132 	void *vapic;
1133 
1134 	if (!irqchip_in_kernel(vcpu->kvm) || !vcpu->arch.apic->vapic_addr)
1135 		return;
1136 
1137 	apic = vcpu->arch.apic;
1138 	tpr = apic_get_reg(apic, APIC_TASKPRI) & 0xff;
1139 	max_irr = apic_find_highest_irr(apic);
1140 	if (max_irr < 0)
1141 		max_irr = 0;
1142 	max_isr = apic_find_highest_isr(apic);
1143 	if (max_isr < 0)
1144 		max_isr = 0;
1145 	data = (tpr & 0xff) | ((max_isr & 0xf0) << 8) | (max_irr << 24);
1146 
1147 	vapic = kmap_atomic(vcpu->arch.apic->vapic_page, KM_USER0);
1148 	*(u32 *)(vapic + offset_in_page(vcpu->arch.apic->vapic_addr)) = data;
1149 	kunmap_atomic(vapic, KM_USER0);
1150 }
1151 
1152 void kvm_lapic_set_vapic_addr(struct kvm_vcpu *vcpu, gpa_t vapic_addr)
1153 {
1154 	if (!irqchip_in_kernel(vcpu->kvm))
1155 		return;
1156 
1157 	vcpu->arch.apic->vapic_addr = vapic_addr;
1158 }
1159