xref: /freebsd/sys/amd64/vmm/io/vlapic.c (revision f4b37ed0f8b307b1f3f0f630ca725d68f1dff30d)
1 /*-
2  * Copyright (c) 2011 NetApp, Inc.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 #include <sys/lock.h>
34 #include <sys/kernel.h>
35 #include <sys/malloc.h>
36 #include <sys/mutex.h>
37 #include <sys/systm.h>
38 #include <sys/smp.h>
39 
40 #include <x86/specialreg.h>
41 #include <x86/apicreg.h>
42 
43 #include <machine/clock.h>
44 #include <machine/smp.h>
45 
46 #include <machine/vmm.h>
47 
48 #include "vmm_lapic.h"
49 #include "vmm_ktr.h"
50 #include "vmm_stat.h"
51 
52 #include "vlapic.h"
53 #include "vlapic_priv.h"
54 #include "vioapic.h"
55 
56 #define	PRIO(x)			((x) >> 4)
57 
58 #define VLAPIC_VERSION		(16)
59 
60 #define	x2apic(vlapic)	(((vlapic)->msr_apicbase & APICBASE_X2APIC) ? 1 : 0)
61 
62 /*
63  * The 'vlapic->timer_mtx' is used to provide mutual exclusion between the
64  * vlapic_callout_handler() and vcpu accesses to:
65  * - timer_freq_bt, timer_period_bt, timer_fire_bt
66  * - timer LVT register
67  */
68 #define	VLAPIC_TIMER_LOCK(vlapic)	mtx_lock_spin(&((vlapic)->timer_mtx))
69 #define	VLAPIC_TIMER_UNLOCK(vlapic)	mtx_unlock_spin(&((vlapic)->timer_mtx))
70 #define	VLAPIC_TIMER_LOCKED(vlapic)	mtx_owned(&((vlapic)->timer_mtx))
71 
72 /*
73  * APIC timer frequency:
74  * - arbitrary but chosen to be in the ballpark of contemporary hardware.
75  * - power-of-two to avoid loss of precision when converted to a bintime.
76  */
77 #define VLAPIC_BUS_FREQ		(128 * 1024 * 1024)
78 
79 static __inline uint32_t
80 vlapic_get_id(struct vlapic *vlapic)
81 {
82 
83 	if (x2apic(vlapic))
84 		return (vlapic->vcpuid);
85 	else
86 		return (vlapic->vcpuid << 24);
87 }
88 
89 static uint32_t
90 x2apic_ldr(struct vlapic *vlapic)
91 {
92 	int apicid;
93 	uint32_t ldr;
94 
95 	apicid = vlapic_get_id(vlapic);
96 	ldr = 1 << (apicid & 0xf);
97 	ldr |= (apicid & 0xffff0) << 12;
98 	return (ldr);
99 }
100 
101 void
102 vlapic_dfr_write_handler(struct vlapic *vlapic)
103 {
104 	struct LAPIC *lapic;
105 
106 	lapic = vlapic->apic_page;
107 	if (x2apic(vlapic)) {
108 		VM_CTR1(vlapic->vm, "ignoring write to DFR in x2apic mode: %#x",
109 		    lapic->dfr);
110 		lapic->dfr = 0;
111 		return;
112 	}
113 
114 	lapic->dfr &= APIC_DFR_MODEL_MASK;
115 	lapic->dfr |= APIC_DFR_RESERVED;
116 
117 	if ((lapic->dfr & APIC_DFR_MODEL_MASK) == APIC_DFR_MODEL_FLAT)
118 		VLAPIC_CTR0(vlapic, "vlapic DFR in Flat Model");
119 	else if ((lapic->dfr & APIC_DFR_MODEL_MASK) == APIC_DFR_MODEL_CLUSTER)
120 		VLAPIC_CTR0(vlapic, "vlapic DFR in Cluster Model");
121 	else
122 		VLAPIC_CTR1(vlapic, "DFR in Unknown Model %#x", lapic->dfr);
123 }
124 
125 void
126 vlapic_ldr_write_handler(struct vlapic *vlapic)
127 {
128 	struct LAPIC *lapic;
129 
130 	lapic = vlapic->apic_page;
131 
132 	/* LDR is read-only in x2apic mode */
133 	if (x2apic(vlapic)) {
134 		VLAPIC_CTR1(vlapic, "ignoring write to LDR in x2apic mode: %#x",
135 		    lapic->ldr);
136 		lapic->ldr = x2apic_ldr(vlapic);
137 	} else {
138 		lapic->ldr &= ~APIC_LDR_RESERVED;
139 		VLAPIC_CTR1(vlapic, "vlapic LDR set to %#x", lapic->ldr);
140 	}
141 }
142 
143 void
144 vlapic_id_write_handler(struct vlapic *vlapic)
145 {
146 	struct LAPIC *lapic;
147 
148 	/*
149 	 * We don't allow the ID register to be modified so reset it back to
150 	 * its default value.
151 	 */
152 	lapic = vlapic->apic_page;
153 	lapic->id = vlapic_get_id(vlapic);
154 }
155 
156 static int
157 vlapic_timer_divisor(uint32_t dcr)
158 {
159 	switch (dcr & 0xB) {
160 	case APIC_TDCR_1:
161 		return (1);
162 	case APIC_TDCR_2:
163 		return (2);
164 	case APIC_TDCR_4:
165 		return (4);
166 	case APIC_TDCR_8:
167 		return (8);
168 	case APIC_TDCR_16:
169 		return (16);
170 	case APIC_TDCR_32:
171 		return (32);
172 	case APIC_TDCR_64:
173 		return (64);
174 	case APIC_TDCR_128:
175 		return (128);
176 	default:
177 		panic("vlapic_timer_divisor: invalid dcr 0x%08x", dcr);
178 	}
179 }
180 
181 #if 0
182 static inline void
183 vlapic_dump_lvt(uint32_t offset, uint32_t *lvt)
184 {
185 	printf("Offset %x: lvt %08x (V:%02x DS:%x M:%x)\n", offset,
186 	    *lvt, *lvt & APIC_LVTT_VECTOR, *lvt & APIC_LVTT_DS,
187 	    *lvt & APIC_LVTT_M);
188 }
189 #endif
190 
191 static uint32_t
192 vlapic_get_ccr(struct vlapic *vlapic)
193 {
194 	struct bintime bt_now, bt_rem;
195 	struct LAPIC *lapic;
196 	uint32_t ccr;
197 
198 	ccr = 0;
199 	lapic = vlapic->apic_page;
200 
201 	VLAPIC_TIMER_LOCK(vlapic);
202 	if (callout_active(&vlapic->callout)) {
203 		/*
204 		 * If the timer is scheduled to expire in the future then
205 		 * compute the value of 'ccr' based on the remaining time.
206 		 */
207 		binuptime(&bt_now);
208 		if (bintime_cmp(&vlapic->timer_fire_bt, &bt_now, >)) {
209 			bt_rem = vlapic->timer_fire_bt;
210 			bintime_sub(&bt_rem, &bt_now);
211 			ccr += bt_rem.sec * BT2FREQ(&vlapic->timer_freq_bt);
212 			ccr += bt_rem.frac / vlapic->timer_freq_bt.frac;
213 		}
214 	}
215 	KASSERT(ccr <= lapic->icr_timer, ("vlapic_get_ccr: invalid ccr %#x, "
216 	    "icr_timer is %#x", ccr, lapic->icr_timer));
217 	VLAPIC_CTR2(vlapic, "vlapic ccr_timer = %#x, icr_timer = %#x",
218 	    ccr, lapic->icr_timer);
219 	VLAPIC_TIMER_UNLOCK(vlapic);
220 	return (ccr);
221 }
222 
223 void
224 vlapic_dcr_write_handler(struct vlapic *vlapic)
225 {
226 	struct LAPIC *lapic;
227 	int divisor;
228 
229 	lapic = vlapic->apic_page;
230 	VLAPIC_TIMER_LOCK(vlapic);
231 
232 	divisor = vlapic_timer_divisor(lapic->dcr_timer);
233 	VLAPIC_CTR2(vlapic, "vlapic dcr_timer=%#x, divisor=%d",
234 	    lapic->dcr_timer, divisor);
235 
236 	/*
237 	 * Update the timer frequency and the timer period.
238 	 *
239 	 * XXX changes to the frequency divider will not take effect until
240 	 * the timer is reloaded.
241 	 */
242 	FREQ2BT(VLAPIC_BUS_FREQ / divisor, &vlapic->timer_freq_bt);
243 	vlapic->timer_period_bt = vlapic->timer_freq_bt;
244 	bintime_mul(&vlapic->timer_period_bt, lapic->icr_timer);
245 
246 	VLAPIC_TIMER_UNLOCK(vlapic);
247 }
248 
249 void
250 vlapic_esr_write_handler(struct vlapic *vlapic)
251 {
252 	struct LAPIC *lapic;
253 
254 	lapic = vlapic->apic_page;
255 	lapic->esr = vlapic->esr_pending;
256 	vlapic->esr_pending = 0;
257 }
258 
259 int
260 vlapic_set_intr_ready(struct vlapic *vlapic, int vector, bool level)
261 {
262 	struct LAPIC *lapic;
263 	uint32_t *irrptr, *tmrptr, mask;
264 	int idx;
265 
266 	KASSERT(vector >= 0 && vector < 256, ("invalid vector %d", vector));
267 
268 	lapic = vlapic->apic_page;
269 	if (!(lapic->svr & APIC_SVR_ENABLE)) {
270 		VLAPIC_CTR1(vlapic, "vlapic is software disabled, ignoring "
271 		    "interrupt %d", vector);
272 		return (0);
273 	}
274 
275 	if (vector < 16) {
276 		vlapic_set_error(vlapic, APIC_ESR_RECEIVE_ILLEGAL_VECTOR);
277 		VLAPIC_CTR1(vlapic, "vlapic ignoring interrupt to vector %d",
278 		    vector);
279 		return (1);
280 	}
281 
282 	if (vlapic->ops.set_intr_ready)
283 		return ((*vlapic->ops.set_intr_ready)(vlapic, vector, level));
284 
285 	idx = (vector / 32) * 4;
286 	mask = 1 << (vector % 32);
287 
288 	irrptr = &lapic->irr0;
289 	atomic_set_int(&irrptr[idx], mask);
290 
291 	/*
292 	 * Verify that the trigger-mode of the interrupt matches with
293 	 * the vlapic TMR registers.
294 	 */
295 	tmrptr = &lapic->tmr0;
296 	if ((tmrptr[idx] & mask) != (level ? mask : 0)) {
297 		VLAPIC_CTR3(vlapic, "vlapic TMR[%d] is 0x%08x but "
298 		    "interrupt is %s-triggered", idx / 4, tmrptr[idx],
299 		    level ? "level" : "edge");
300 	}
301 
302 	VLAPIC_CTR_IRR(vlapic, "vlapic_set_intr_ready");
303 	return (1);
304 }
305 
306 static __inline uint32_t *
307 vlapic_get_lvtptr(struct vlapic *vlapic, uint32_t offset)
308 {
309 	struct LAPIC	*lapic = vlapic->apic_page;
310 	int 		 i;
311 
312 	switch (offset) {
313 	case APIC_OFFSET_CMCI_LVT:
314 		return (&lapic->lvt_cmci);
315 	case APIC_OFFSET_TIMER_LVT ... APIC_OFFSET_ERROR_LVT:
316 		i = (offset - APIC_OFFSET_TIMER_LVT) >> 2;
317 		return ((&lapic->lvt_timer) + i);;
318 	default:
319 		panic("vlapic_get_lvt: invalid LVT\n");
320 	}
321 }
322 
323 static __inline int
324 lvt_off_to_idx(uint32_t offset)
325 {
326 	int index;
327 
328 	switch (offset) {
329 	case APIC_OFFSET_CMCI_LVT:
330 		index = APIC_LVT_CMCI;
331 		break;
332 	case APIC_OFFSET_TIMER_LVT:
333 		index = APIC_LVT_TIMER;
334 		break;
335 	case APIC_OFFSET_THERM_LVT:
336 		index = APIC_LVT_THERMAL;
337 		break;
338 	case APIC_OFFSET_PERF_LVT:
339 		index = APIC_LVT_PMC;
340 		break;
341 	case APIC_OFFSET_LINT0_LVT:
342 		index = APIC_LVT_LINT0;
343 		break;
344 	case APIC_OFFSET_LINT1_LVT:
345 		index = APIC_LVT_LINT1;
346 		break;
347 	case APIC_OFFSET_ERROR_LVT:
348 		index = APIC_LVT_ERROR;
349 		break;
350 	default:
351 		index = -1;
352 		break;
353 	}
354 	KASSERT(index >= 0 && index <= VLAPIC_MAXLVT_INDEX, ("lvt_off_to_idx: "
355 	    "invalid lvt index %d for offset %#x", index, offset));
356 
357 	return (index);
358 }
359 
360 static __inline uint32_t
361 vlapic_get_lvt(struct vlapic *vlapic, uint32_t offset)
362 {
363 	int idx;
364 	uint32_t val;
365 
366 	idx = lvt_off_to_idx(offset);
367 	val = atomic_load_acq_32(&vlapic->lvt_last[idx]);
368 	return (val);
369 }
370 
371 void
372 vlapic_lvt_write_handler(struct vlapic *vlapic, uint32_t offset)
373 {
374 	uint32_t *lvtptr, mask, val;
375 	struct LAPIC *lapic;
376 	int idx;
377 
378 	lapic = vlapic->apic_page;
379 	lvtptr = vlapic_get_lvtptr(vlapic, offset);
380 	val = *lvtptr;
381 	idx = lvt_off_to_idx(offset);
382 
383 	if (!(lapic->svr & APIC_SVR_ENABLE))
384 		val |= APIC_LVT_M;
385 	mask = APIC_LVT_M | APIC_LVT_DS | APIC_LVT_VECTOR;
386 	switch (offset) {
387 	case APIC_OFFSET_TIMER_LVT:
388 		mask |= APIC_LVTT_TM;
389 		break;
390 	case APIC_OFFSET_ERROR_LVT:
391 		break;
392 	case APIC_OFFSET_LINT0_LVT:
393 	case APIC_OFFSET_LINT1_LVT:
394 		mask |= APIC_LVT_TM | APIC_LVT_RIRR | APIC_LVT_IIPP;
395 		/* FALLTHROUGH */
396 	default:
397 		mask |= APIC_LVT_DM;
398 		break;
399 	}
400 	val &= mask;
401 	*lvtptr = val;
402 	atomic_store_rel_32(&vlapic->lvt_last[idx], val);
403 }
404 
405 static void
406 vlapic_mask_lvts(struct vlapic *vlapic)
407 {
408 	struct LAPIC *lapic = vlapic->apic_page;
409 
410 	lapic->lvt_cmci |= APIC_LVT_M;
411 	vlapic_lvt_write_handler(vlapic, APIC_OFFSET_CMCI_LVT);
412 
413 	lapic->lvt_timer |= APIC_LVT_M;
414 	vlapic_lvt_write_handler(vlapic, APIC_OFFSET_TIMER_LVT);
415 
416 	lapic->lvt_thermal |= APIC_LVT_M;
417 	vlapic_lvt_write_handler(vlapic, APIC_OFFSET_THERM_LVT);
418 
419 	lapic->lvt_pcint |= APIC_LVT_M;
420 	vlapic_lvt_write_handler(vlapic, APIC_OFFSET_PERF_LVT);
421 
422 	lapic->lvt_lint0 |= APIC_LVT_M;
423 	vlapic_lvt_write_handler(vlapic, APIC_OFFSET_LINT0_LVT);
424 
425 	lapic->lvt_lint1 |= APIC_LVT_M;
426 	vlapic_lvt_write_handler(vlapic, APIC_OFFSET_LINT1_LVT);
427 
428 	lapic->lvt_error |= APIC_LVT_M;
429 	vlapic_lvt_write_handler(vlapic, APIC_OFFSET_ERROR_LVT);
430 }
431 
432 static int
433 vlapic_fire_lvt(struct vlapic *vlapic, uint32_t lvt)
434 {
435 	uint32_t vec, mode;
436 
437 	if (lvt & APIC_LVT_M)
438 		return (0);
439 
440 	vec = lvt & APIC_LVT_VECTOR;
441 	mode = lvt & APIC_LVT_DM;
442 
443 	switch (mode) {
444 	case APIC_LVT_DM_FIXED:
445 		if (vec < 16) {
446 			vlapic_set_error(vlapic, APIC_ESR_SEND_ILLEGAL_VECTOR);
447 			return (0);
448 		}
449 		if (vlapic_set_intr_ready(vlapic, vec, false))
450 			vcpu_notify_event(vlapic->vm, vlapic->vcpuid, true);
451 		break;
452 	case APIC_LVT_DM_NMI:
453 		vm_inject_nmi(vlapic->vm, vlapic->vcpuid);
454 		break;
455 	case APIC_LVT_DM_EXTINT:
456 		vm_inject_extint(vlapic->vm, vlapic->vcpuid);
457 		break;
458 	default:
459 		// Other modes ignored
460 		return (0);
461 	}
462 	return (1);
463 }
464 
465 #if 1
466 static void
467 dump_isrvec_stk(struct vlapic *vlapic)
468 {
469 	int i;
470 	uint32_t *isrptr;
471 
472 	isrptr = &vlapic->apic_page->isr0;
473 	for (i = 0; i < 8; i++)
474 		printf("ISR%d 0x%08x\n", i, isrptr[i * 4]);
475 
476 	for (i = 0; i <= vlapic->isrvec_stk_top; i++)
477 		printf("isrvec_stk[%d] = %d\n", i, vlapic->isrvec_stk[i]);
478 }
479 #endif
480 
481 /*
482  * Algorithm adopted from section "Interrupt, Task and Processor Priority"
483  * in Intel Architecture Manual Vol 3a.
484  */
485 static void
486 vlapic_update_ppr(struct vlapic *vlapic)
487 {
488 	int isrvec, tpr, ppr;
489 
490 	/*
491 	 * Note that the value on the stack at index 0 is always 0.
492 	 *
493 	 * This is a placeholder for the value of ISRV when none of the
494 	 * bits is set in the ISRx registers.
495 	 */
496 	isrvec = vlapic->isrvec_stk[vlapic->isrvec_stk_top];
497 	tpr = vlapic->apic_page->tpr;
498 
499 #if 1
500 	{
501 		int i, lastprio, curprio, vector, idx;
502 		uint32_t *isrptr;
503 
504 		if (vlapic->isrvec_stk_top == 0 && isrvec != 0)
505 			panic("isrvec_stk is corrupted: %d", isrvec);
506 
507 		/*
508 		 * Make sure that the priority of the nested interrupts is
509 		 * always increasing.
510 		 */
511 		lastprio = -1;
512 		for (i = 1; i <= vlapic->isrvec_stk_top; i++) {
513 			curprio = PRIO(vlapic->isrvec_stk[i]);
514 			if (curprio <= lastprio) {
515 				dump_isrvec_stk(vlapic);
516 				panic("isrvec_stk does not satisfy invariant");
517 			}
518 			lastprio = curprio;
519 		}
520 
521 		/*
522 		 * Make sure that each bit set in the ISRx registers has a
523 		 * corresponding entry on the isrvec stack.
524 		 */
525 		i = 1;
526 		isrptr = &vlapic->apic_page->isr0;
527 		for (vector = 0; vector < 256; vector++) {
528 			idx = (vector / 32) * 4;
529 			if (isrptr[idx] & (1 << (vector % 32))) {
530 				if (i > vlapic->isrvec_stk_top ||
531 				    vlapic->isrvec_stk[i] != vector) {
532 					dump_isrvec_stk(vlapic);
533 					panic("ISR and isrvec_stk out of sync");
534 				}
535 				i++;
536 			}
537 		}
538 	}
539 #endif
540 
541 	if (PRIO(tpr) >= PRIO(isrvec))
542 		ppr = tpr;
543 	else
544 		ppr = isrvec & 0xf0;
545 
546 	vlapic->apic_page->ppr = ppr;
547 	VLAPIC_CTR1(vlapic, "vlapic_update_ppr 0x%02x", ppr);
548 }
549 
550 static VMM_STAT(VLAPIC_GRATUITOUS_EOI, "EOI without any in-service interrupt");
551 
552 static void
553 vlapic_process_eoi(struct vlapic *vlapic)
554 {
555 	struct LAPIC	*lapic = vlapic->apic_page;
556 	uint32_t	*isrptr, *tmrptr;
557 	int		i, idx, bitpos, vector;
558 
559 	isrptr = &lapic->isr0;
560 	tmrptr = &lapic->tmr0;
561 
562 	for (i = 7; i >= 0; i--) {
563 		idx = i * 4;
564 		bitpos = fls(isrptr[idx]);
565 		if (bitpos-- != 0) {
566 			if (vlapic->isrvec_stk_top <= 0) {
567 				panic("invalid vlapic isrvec_stk_top %d",
568 				      vlapic->isrvec_stk_top);
569 			}
570 			isrptr[idx] &= ~(1 << bitpos);
571 			vector = i * 32 + bitpos;
572 			VCPU_CTR1(vlapic->vm, vlapic->vcpuid, "EOI vector %d",
573 			    vector);
574 			VLAPIC_CTR_ISR(vlapic, "vlapic_process_eoi");
575 			vlapic->isrvec_stk_top--;
576 			vlapic_update_ppr(vlapic);
577 			if ((tmrptr[idx] & (1 << bitpos)) != 0) {
578 				vioapic_process_eoi(vlapic->vm, vlapic->vcpuid,
579 				    vector);
580 			}
581 			return;
582 		}
583 	}
584 	VCPU_CTR0(vlapic->vm, vlapic->vcpuid, "Gratuitous EOI");
585 	vmm_stat_incr(vlapic->vm, vlapic->vcpuid, VLAPIC_GRATUITOUS_EOI, 1);
586 }
587 
588 static __inline int
589 vlapic_get_lvt_field(uint32_t lvt, uint32_t mask)
590 {
591 
592 	return (lvt & mask);
593 }
594 
595 static __inline int
596 vlapic_periodic_timer(struct vlapic *vlapic)
597 {
598 	uint32_t lvt;
599 
600 	lvt = vlapic_get_lvt(vlapic, APIC_OFFSET_TIMER_LVT);
601 
602 	return (vlapic_get_lvt_field(lvt, APIC_LVTT_TM_PERIODIC));
603 }
604 
605 static VMM_STAT(VLAPIC_INTR_ERROR, "error interrupts generated by vlapic");
606 
607 void
608 vlapic_set_error(struct vlapic *vlapic, uint32_t mask)
609 {
610 	uint32_t lvt;
611 
612 	vlapic->esr_pending |= mask;
613 	if (vlapic->esr_firing)
614 		return;
615 	vlapic->esr_firing = 1;
616 
617 	// The error LVT always uses the fixed delivery mode.
618 	lvt = vlapic_get_lvt(vlapic, APIC_OFFSET_ERROR_LVT);
619 	if (vlapic_fire_lvt(vlapic, lvt | APIC_LVT_DM_FIXED)) {
620 		vmm_stat_incr(vlapic->vm, vlapic->vcpuid, VLAPIC_INTR_ERROR, 1);
621 	}
622 	vlapic->esr_firing = 0;
623 }
624 
625 static VMM_STAT(VLAPIC_INTR_TIMER, "timer interrupts generated by vlapic");
626 
627 static void
628 vlapic_fire_timer(struct vlapic *vlapic)
629 {
630 	uint32_t lvt;
631 
632 	KASSERT(VLAPIC_TIMER_LOCKED(vlapic), ("vlapic_fire_timer not locked"));
633 
634 	// The timer LVT always uses the fixed delivery mode.
635 	lvt = vlapic_get_lvt(vlapic, APIC_OFFSET_TIMER_LVT);
636 	if (vlapic_fire_lvt(vlapic, lvt | APIC_LVT_DM_FIXED)) {
637 		VLAPIC_CTR0(vlapic, "vlapic timer fired");
638 		vmm_stat_incr(vlapic->vm, vlapic->vcpuid, VLAPIC_INTR_TIMER, 1);
639 	}
640 }
641 
642 static VMM_STAT(VLAPIC_INTR_CMC,
643     "corrected machine check interrupts generated by vlapic");
644 
645 void
646 vlapic_fire_cmci(struct vlapic *vlapic)
647 {
648 	uint32_t lvt;
649 
650 	lvt = vlapic_get_lvt(vlapic, APIC_OFFSET_CMCI_LVT);
651 	if (vlapic_fire_lvt(vlapic, lvt)) {
652 		vmm_stat_incr(vlapic->vm, vlapic->vcpuid, VLAPIC_INTR_CMC, 1);
653 	}
654 }
655 
656 static VMM_STAT_ARRAY(LVTS_TRIGGERRED, VLAPIC_MAXLVT_INDEX + 1,
657     "lvts triggered");
658 
659 int
660 vlapic_trigger_lvt(struct vlapic *vlapic, int vector)
661 {
662 	uint32_t lvt;
663 
664 	if (vlapic_enabled(vlapic) == false) {
665 		/*
666 		 * When the local APIC is global/hardware disabled,
667 		 * LINT[1:0] pins are configured as INTR and NMI pins,
668 		 * respectively.
669 		*/
670 		switch (vector) {
671 			case APIC_LVT_LINT0:
672 				vm_inject_extint(vlapic->vm, vlapic->vcpuid);
673 				break;
674 			case APIC_LVT_LINT1:
675 				vm_inject_nmi(vlapic->vm, vlapic->vcpuid);
676 				break;
677 			default:
678 				break;
679 		}
680 		return (0);
681 	}
682 
683 	switch (vector) {
684 	case APIC_LVT_LINT0:
685 		lvt = vlapic_get_lvt(vlapic, APIC_OFFSET_LINT0_LVT);
686 		break;
687 	case APIC_LVT_LINT1:
688 		lvt = vlapic_get_lvt(vlapic, APIC_OFFSET_LINT1_LVT);
689 		break;
690 	case APIC_LVT_TIMER:
691 		lvt = vlapic_get_lvt(vlapic, APIC_OFFSET_TIMER_LVT);
692 		lvt |= APIC_LVT_DM_FIXED;
693 		break;
694 	case APIC_LVT_ERROR:
695 		lvt = vlapic_get_lvt(vlapic, APIC_OFFSET_ERROR_LVT);
696 		lvt |= APIC_LVT_DM_FIXED;
697 		break;
698 	case APIC_LVT_PMC:
699 		lvt = vlapic_get_lvt(vlapic, APIC_OFFSET_PERF_LVT);
700 		break;
701 	case APIC_LVT_THERMAL:
702 		lvt = vlapic_get_lvt(vlapic, APIC_OFFSET_THERM_LVT);
703 		break;
704 	case APIC_LVT_CMCI:
705 		lvt = vlapic_get_lvt(vlapic, APIC_OFFSET_CMCI_LVT);
706 		break;
707 	default:
708 		return (EINVAL);
709 	}
710 	if (vlapic_fire_lvt(vlapic, lvt)) {
711 		vmm_stat_array_incr(vlapic->vm, vlapic->vcpuid,
712 		    LVTS_TRIGGERRED, vector, 1);
713 	}
714 	return (0);
715 }
716 
717 static void
718 vlapic_callout_handler(void *arg)
719 {
720 	struct vlapic *vlapic;
721 	struct bintime bt, btnow;
722 	sbintime_t rem_sbt;
723 
724 	vlapic = arg;
725 
726 	VLAPIC_TIMER_LOCK(vlapic);
727 	if (callout_pending(&vlapic->callout))	/* callout was reset */
728 		goto done;
729 
730 	if (!callout_active(&vlapic->callout))	/* callout was stopped */
731 		goto done;
732 
733 	callout_deactivate(&vlapic->callout);
734 
735 	vlapic_fire_timer(vlapic);
736 
737 	if (vlapic_periodic_timer(vlapic)) {
738 		binuptime(&btnow);
739 		KASSERT(bintime_cmp(&btnow, &vlapic->timer_fire_bt, >=),
740 		    ("vlapic callout at %#lx.%#lx, expected at %#lx.#%lx",
741 		    btnow.sec, btnow.frac, vlapic->timer_fire_bt.sec,
742 		    vlapic->timer_fire_bt.frac));
743 
744 		/*
745 		 * Compute the delta between when the timer was supposed to
746 		 * fire and the present time.
747 		 */
748 		bt = btnow;
749 		bintime_sub(&bt, &vlapic->timer_fire_bt);
750 
751 		rem_sbt = bttosbt(vlapic->timer_period_bt);
752 		if (bintime_cmp(&bt, &vlapic->timer_period_bt, <)) {
753 			/*
754 			 * Adjust the time until the next countdown downward
755 			 * to account for the lost time.
756 			 */
757 			rem_sbt -= bttosbt(bt);
758 		} else {
759 			/*
760 			 * If the delta is greater than the timer period then
761 			 * just reset our time base instead of trying to catch
762 			 * up.
763 			 */
764 			vlapic->timer_fire_bt = btnow;
765 			VLAPIC_CTR2(vlapic, "vlapic timer lagging by %lu "
766 			    "usecs, period is %lu usecs - resetting time base",
767 			    bttosbt(bt) / SBT_1US,
768 			    bttosbt(vlapic->timer_period_bt) / SBT_1US);
769 		}
770 
771 		bintime_add(&vlapic->timer_fire_bt, &vlapic->timer_period_bt);
772 		callout_reset_sbt(&vlapic->callout, rem_sbt, 0,
773 		    vlapic_callout_handler, vlapic, 0);
774 	}
775 done:
776 	VLAPIC_TIMER_UNLOCK(vlapic);
777 }
778 
779 void
780 vlapic_icrtmr_write_handler(struct vlapic *vlapic)
781 {
782 	struct LAPIC *lapic;
783 	sbintime_t sbt;
784 	uint32_t icr_timer;
785 
786 	VLAPIC_TIMER_LOCK(vlapic);
787 
788 	lapic = vlapic->apic_page;
789 	icr_timer = lapic->icr_timer;
790 
791 	vlapic->timer_period_bt = vlapic->timer_freq_bt;
792 	bintime_mul(&vlapic->timer_period_bt, icr_timer);
793 
794 	if (icr_timer != 0) {
795 		binuptime(&vlapic->timer_fire_bt);
796 		bintime_add(&vlapic->timer_fire_bt, &vlapic->timer_period_bt);
797 
798 		sbt = bttosbt(vlapic->timer_period_bt);
799 		callout_reset_sbt(&vlapic->callout, sbt, 0,
800 		    vlapic_callout_handler, vlapic, 0);
801 	} else
802 		callout_stop(&vlapic->callout);
803 
804 	VLAPIC_TIMER_UNLOCK(vlapic);
805 }
806 
807 /*
808  * This function populates 'dmask' with the set of vcpus that match the
809  * addressing specified by the (dest, phys, lowprio) tuple.
810  *
811  * 'x2apic_dest' specifies whether 'dest' is interpreted as x2APIC (32-bit)
812  * or xAPIC (8-bit) destination field.
813  */
814 static void
815 vlapic_calcdest(struct vm *vm, cpuset_t *dmask, uint32_t dest, bool phys,
816     bool lowprio, bool x2apic_dest)
817 {
818 	struct vlapic *vlapic;
819 	uint32_t dfr, ldr, ldest, cluster;
820 	uint32_t mda_flat_ldest, mda_cluster_ldest, mda_ldest, mda_cluster_id;
821 	cpuset_t amask;
822 	int vcpuid;
823 
824 	if ((x2apic_dest && dest == 0xffffffff) ||
825 	    (!x2apic_dest && dest == 0xff)) {
826 		/*
827 		 * Broadcast in both logical and physical modes.
828 		 */
829 		*dmask = vm_active_cpus(vm);
830 		return;
831 	}
832 
833 	if (phys) {
834 		/*
835 		 * Physical mode: destination is APIC ID.
836 		 */
837 		CPU_ZERO(dmask);
838 		vcpuid = vm_apicid2vcpuid(vm, dest);
839 		if (vcpuid < VM_MAXCPU)
840 			CPU_SET(vcpuid, dmask);
841 	} else {
842 		/*
843 		 * In the "Flat Model" the MDA is interpreted as an 8-bit wide
844 		 * bitmask. This model is only avilable in the xAPIC mode.
845 		 */
846 		mda_flat_ldest = dest & 0xff;
847 
848 		/*
849 		 * In the "Cluster Model" the MDA is used to identify a
850 		 * specific cluster and a set of APICs in that cluster.
851 		 */
852 		if (x2apic_dest) {
853 			mda_cluster_id = dest >> 16;
854 			mda_cluster_ldest = dest & 0xffff;
855 		} else {
856 			mda_cluster_id = (dest >> 4) & 0xf;
857 			mda_cluster_ldest = dest & 0xf;
858 		}
859 
860 		/*
861 		 * Logical mode: match each APIC that has a bit set
862 		 * in it's LDR that matches a bit in the ldest.
863 		 */
864 		CPU_ZERO(dmask);
865 		amask = vm_active_cpus(vm);
866 		while ((vcpuid = CPU_FFS(&amask)) != 0) {
867 			vcpuid--;
868 			CPU_CLR(vcpuid, &amask);
869 
870 			vlapic = vm_lapic(vm, vcpuid);
871 			dfr = vlapic->apic_page->dfr;
872 			ldr = vlapic->apic_page->ldr;
873 
874 			if ((dfr & APIC_DFR_MODEL_MASK) ==
875 			    APIC_DFR_MODEL_FLAT) {
876 				ldest = ldr >> 24;
877 				mda_ldest = mda_flat_ldest;
878 			} else if ((dfr & APIC_DFR_MODEL_MASK) ==
879 			    APIC_DFR_MODEL_CLUSTER) {
880 				if (x2apic(vlapic)) {
881 					cluster = ldr >> 16;
882 					ldest = ldr & 0xffff;
883 				} else {
884 					cluster = ldr >> 28;
885 					ldest = (ldr >> 24) & 0xf;
886 				}
887 				if (cluster != mda_cluster_id)
888 					continue;
889 				mda_ldest = mda_cluster_ldest;
890 			} else {
891 				/*
892 				 * Guest has configured a bad logical
893 				 * model for this vcpu - skip it.
894 				 */
895 				VLAPIC_CTR1(vlapic, "vlapic has bad logical "
896 				    "model %x - cannot deliver interrupt", dfr);
897 				continue;
898 			}
899 
900 			if ((mda_ldest & ldest) != 0) {
901 				CPU_SET(vcpuid, dmask);
902 				if (lowprio)
903 					break;
904 			}
905 		}
906 	}
907 }
908 
909 static VMM_STAT_ARRAY(IPIS_SENT, VM_MAXCPU, "ipis sent to vcpu");
910 
911 static void
912 vlapic_set_tpr(struct vlapic *vlapic, uint8_t val)
913 {
914 	struct LAPIC *lapic = vlapic->apic_page;
915 
916 	if (lapic->tpr != val) {
917 		VCPU_CTR2(vlapic->vm, vlapic->vcpuid, "vlapic TPR changed "
918 		    "from %#x to %#x", lapic->tpr, val);
919 		lapic->tpr = val;
920 		vlapic_update_ppr(vlapic);
921 	}
922 }
923 
924 static uint8_t
925 vlapic_get_tpr(struct vlapic *vlapic)
926 {
927 	struct LAPIC *lapic = vlapic->apic_page;
928 
929 	return (lapic->tpr);
930 }
931 
932 void
933 vlapic_set_cr8(struct vlapic *vlapic, uint64_t val)
934 {
935 	uint8_t tpr;
936 
937 	if (val & ~0xf) {
938 		vm_inject_gp(vlapic->vm, vlapic->vcpuid);
939 		return;
940 	}
941 
942 	tpr = val << 4;
943 	vlapic_set_tpr(vlapic, tpr);
944 }
945 
946 uint64_t
947 vlapic_get_cr8(struct vlapic *vlapic)
948 {
949 	uint8_t tpr;
950 
951 	tpr = vlapic_get_tpr(vlapic);
952 	return (tpr >> 4);
953 }
954 
955 int
956 vlapic_icrlo_write_handler(struct vlapic *vlapic, bool *retu)
957 {
958 	int i;
959 	bool phys;
960 	cpuset_t dmask;
961 	uint64_t icrval;
962 	uint32_t dest, vec, mode;
963 	struct vlapic *vlapic2;
964 	struct vm_exit *vmexit;
965 	struct LAPIC *lapic;
966 
967 	lapic = vlapic->apic_page;
968 	lapic->icr_lo &= ~APIC_DELSTAT_PEND;
969 	icrval = ((uint64_t)lapic->icr_hi << 32) | lapic->icr_lo;
970 
971 	if (x2apic(vlapic))
972 		dest = icrval >> 32;
973 	else
974 		dest = icrval >> (32 + 24);
975 	vec = icrval & APIC_VECTOR_MASK;
976 	mode = icrval & APIC_DELMODE_MASK;
977 
978 	if (mode == APIC_DELMODE_FIXED && vec < 16) {
979 		vlapic_set_error(vlapic, APIC_ESR_SEND_ILLEGAL_VECTOR);
980 		VLAPIC_CTR1(vlapic, "Ignoring invalid IPI %d", vec);
981 		return (0);
982 	}
983 
984 	VLAPIC_CTR2(vlapic, "icrlo 0x%016lx triggered ipi %d", icrval, vec);
985 
986 	if (mode == APIC_DELMODE_FIXED || mode == APIC_DELMODE_NMI) {
987 		switch (icrval & APIC_DEST_MASK) {
988 		case APIC_DEST_DESTFLD:
989 			phys = ((icrval & APIC_DESTMODE_LOG) == 0);
990 			vlapic_calcdest(vlapic->vm, &dmask, dest, phys, false,
991 			    x2apic(vlapic));
992 			break;
993 		case APIC_DEST_SELF:
994 			CPU_SETOF(vlapic->vcpuid, &dmask);
995 			break;
996 		case APIC_DEST_ALLISELF:
997 			dmask = vm_active_cpus(vlapic->vm);
998 			break;
999 		case APIC_DEST_ALLESELF:
1000 			dmask = vm_active_cpus(vlapic->vm);
1001 			CPU_CLR(vlapic->vcpuid, &dmask);
1002 			break;
1003 		default:
1004 			CPU_ZERO(&dmask);	/* satisfy gcc */
1005 			break;
1006 		}
1007 
1008 		while ((i = CPU_FFS(&dmask)) != 0) {
1009 			i--;
1010 			CPU_CLR(i, &dmask);
1011 			if (mode == APIC_DELMODE_FIXED) {
1012 				lapic_intr_edge(vlapic->vm, i, vec);
1013 				vmm_stat_array_incr(vlapic->vm, vlapic->vcpuid,
1014 						    IPIS_SENT, i, 1);
1015 				VLAPIC_CTR2(vlapic, "vlapic sending ipi %d "
1016 				    "to vcpuid %d", vec, i);
1017 			} else {
1018 				vm_inject_nmi(vlapic->vm, i);
1019 				VLAPIC_CTR1(vlapic, "vlapic sending ipi nmi "
1020 				    "to vcpuid %d", i);
1021 			}
1022 		}
1023 
1024 		return (0);	/* handled completely in the kernel */
1025 	}
1026 
1027 	if (mode == APIC_DELMODE_INIT) {
1028 		if ((icrval & APIC_LEVEL_MASK) == APIC_LEVEL_DEASSERT)
1029 			return (0);
1030 
1031 		if (vlapic->vcpuid == 0 && dest != 0 && dest < VM_MAXCPU) {
1032 			vlapic2 = vm_lapic(vlapic->vm, dest);
1033 
1034 			/* move from INIT to waiting-for-SIPI state */
1035 			if (vlapic2->boot_state == BS_INIT) {
1036 				vlapic2->boot_state = BS_SIPI;
1037 			}
1038 
1039 			return (0);
1040 		}
1041 	}
1042 
1043 	if (mode == APIC_DELMODE_STARTUP) {
1044 		if (vlapic->vcpuid == 0 && dest != 0 && dest < VM_MAXCPU) {
1045 			vlapic2 = vm_lapic(vlapic->vm, dest);
1046 
1047 			/*
1048 			 * Ignore SIPIs in any state other than wait-for-SIPI
1049 			 */
1050 			if (vlapic2->boot_state != BS_SIPI)
1051 				return (0);
1052 
1053 			vlapic2->boot_state = BS_RUNNING;
1054 
1055 			*retu = true;
1056 			vmexit = vm_exitinfo(vlapic->vm, vlapic->vcpuid);
1057 			vmexit->exitcode = VM_EXITCODE_SPINUP_AP;
1058 			vmexit->u.spinup_ap.vcpu = dest;
1059 			vmexit->u.spinup_ap.rip = vec << PAGE_SHIFT;
1060 
1061 			return (0);
1062 		}
1063 	}
1064 
1065 	/*
1066 	 * This will cause a return to userland.
1067 	 */
1068 	return (1);
1069 }
1070 
1071 void
1072 vlapic_self_ipi_handler(struct vlapic *vlapic, uint64_t val)
1073 {
1074 	int vec;
1075 
1076 	KASSERT(x2apic(vlapic), ("SELF_IPI does not exist in xAPIC mode"));
1077 
1078 	vec = val & 0xff;
1079 	lapic_intr_edge(vlapic->vm, vlapic->vcpuid, vec);
1080 	vmm_stat_array_incr(vlapic->vm, vlapic->vcpuid, IPIS_SENT,
1081 	    vlapic->vcpuid, 1);
1082 	VLAPIC_CTR1(vlapic, "vlapic self-ipi %d", vec);
1083 }
1084 
1085 int
1086 vlapic_pending_intr(struct vlapic *vlapic, int *vecptr)
1087 {
1088 	struct LAPIC	*lapic = vlapic->apic_page;
1089 	int	  	 idx, i, bitpos, vector;
1090 	uint32_t	*irrptr, val;
1091 
1092 	if (vlapic->ops.pending_intr)
1093 		return ((*vlapic->ops.pending_intr)(vlapic, vecptr));
1094 
1095 	irrptr = &lapic->irr0;
1096 
1097 	for (i = 7; i >= 0; i--) {
1098 		idx = i * 4;
1099 		val = atomic_load_acq_int(&irrptr[idx]);
1100 		bitpos = fls(val);
1101 		if (bitpos != 0) {
1102 			vector = i * 32 + (bitpos - 1);
1103 			if (PRIO(vector) > PRIO(lapic->ppr)) {
1104 				VLAPIC_CTR1(vlapic, "pending intr %d", vector);
1105 				if (vecptr != NULL)
1106 					*vecptr = vector;
1107 				return (1);
1108 			} else
1109 				break;
1110 		}
1111 	}
1112 	return (0);
1113 }
1114 
1115 void
1116 vlapic_intr_accepted(struct vlapic *vlapic, int vector)
1117 {
1118 	struct LAPIC	*lapic = vlapic->apic_page;
1119 	uint32_t	*irrptr, *isrptr;
1120 	int		idx, stk_top;
1121 
1122 	if (vlapic->ops.intr_accepted)
1123 		return ((*vlapic->ops.intr_accepted)(vlapic, vector));
1124 
1125 	/*
1126 	 * clear the ready bit for vector being accepted in irr
1127 	 * and set the vector as in service in isr.
1128 	 */
1129 	idx = (vector / 32) * 4;
1130 
1131 	irrptr = &lapic->irr0;
1132 	atomic_clear_int(&irrptr[idx], 1 << (vector % 32));
1133 	VLAPIC_CTR_IRR(vlapic, "vlapic_intr_accepted");
1134 
1135 	isrptr = &lapic->isr0;
1136 	isrptr[idx] |= 1 << (vector % 32);
1137 	VLAPIC_CTR_ISR(vlapic, "vlapic_intr_accepted");
1138 
1139 	/*
1140 	 * Update the PPR
1141 	 */
1142 	vlapic->isrvec_stk_top++;
1143 
1144 	stk_top = vlapic->isrvec_stk_top;
1145 	if (stk_top >= ISRVEC_STK_SIZE)
1146 		panic("isrvec_stk_top overflow %d", stk_top);
1147 
1148 	vlapic->isrvec_stk[stk_top] = vector;
1149 	vlapic_update_ppr(vlapic);
1150 }
1151 
1152 void
1153 vlapic_svr_write_handler(struct vlapic *vlapic)
1154 {
1155 	struct LAPIC *lapic;
1156 	uint32_t old, new, changed;
1157 
1158 	lapic = vlapic->apic_page;
1159 
1160 	new = lapic->svr;
1161 	old = vlapic->svr_last;
1162 	vlapic->svr_last = new;
1163 
1164 	changed = old ^ new;
1165 	if ((changed & APIC_SVR_ENABLE) != 0) {
1166 		if ((new & APIC_SVR_ENABLE) == 0) {
1167 			/*
1168 			 * The apic is now disabled so stop the apic timer
1169 			 * and mask all the LVT entries.
1170 			 */
1171 			VLAPIC_CTR0(vlapic, "vlapic is software-disabled");
1172 			VLAPIC_TIMER_LOCK(vlapic);
1173 			callout_stop(&vlapic->callout);
1174 			VLAPIC_TIMER_UNLOCK(vlapic);
1175 			vlapic_mask_lvts(vlapic);
1176 		} else {
1177 			/*
1178 			 * The apic is now enabled so restart the apic timer
1179 			 * if it is configured in periodic mode.
1180 			 */
1181 			VLAPIC_CTR0(vlapic, "vlapic is software-enabled");
1182 			if (vlapic_periodic_timer(vlapic))
1183 				vlapic_icrtmr_write_handler(vlapic);
1184 		}
1185 	}
1186 }
1187 
1188 int
1189 vlapic_read(struct vlapic *vlapic, int mmio_access, uint64_t offset,
1190     uint64_t *data, bool *retu)
1191 {
1192 	struct LAPIC	*lapic = vlapic->apic_page;
1193 	uint32_t	*reg;
1194 	int		 i;
1195 
1196 	/* Ignore MMIO accesses in x2APIC mode */
1197 	if (x2apic(vlapic) && mmio_access) {
1198 		VLAPIC_CTR1(vlapic, "MMIO read from offset %#lx in x2APIC mode",
1199 		    offset);
1200 		*data = 0;
1201 		goto done;
1202 	}
1203 
1204 	if (!x2apic(vlapic) && !mmio_access) {
1205 		/*
1206 		 * XXX Generate GP fault for MSR accesses in xAPIC mode
1207 		 */
1208 		VLAPIC_CTR1(vlapic, "x2APIC MSR read from offset %#lx in "
1209 		    "xAPIC mode", offset);
1210 		*data = 0;
1211 		goto done;
1212 	}
1213 
1214 	if (offset > sizeof(*lapic)) {
1215 		*data = 0;
1216 		goto done;
1217 	}
1218 
1219 	offset &= ~3;
1220 	switch(offset)
1221 	{
1222 		case APIC_OFFSET_ID:
1223 			*data = lapic->id;
1224 			break;
1225 		case APIC_OFFSET_VER:
1226 			*data = lapic->version;
1227 			break;
1228 		case APIC_OFFSET_TPR:
1229 			*data = vlapic_get_tpr(vlapic);
1230 			break;
1231 		case APIC_OFFSET_APR:
1232 			*data = lapic->apr;
1233 			break;
1234 		case APIC_OFFSET_PPR:
1235 			*data = lapic->ppr;
1236 			break;
1237 		case APIC_OFFSET_EOI:
1238 			*data = lapic->eoi;
1239 			break;
1240 		case APIC_OFFSET_LDR:
1241 			*data = lapic->ldr;
1242 			break;
1243 		case APIC_OFFSET_DFR:
1244 			*data = lapic->dfr;
1245 			break;
1246 		case APIC_OFFSET_SVR:
1247 			*data = lapic->svr;
1248 			break;
1249 		case APIC_OFFSET_ISR0 ... APIC_OFFSET_ISR7:
1250 			i = (offset - APIC_OFFSET_ISR0) >> 2;
1251 			reg = &lapic->isr0;
1252 			*data = *(reg + i);
1253 			break;
1254 		case APIC_OFFSET_TMR0 ... APIC_OFFSET_TMR7:
1255 			i = (offset - APIC_OFFSET_TMR0) >> 2;
1256 			reg = &lapic->tmr0;
1257 			*data = *(reg + i);
1258 			break;
1259 		case APIC_OFFSET_IRR0 ... APIC_OFFSET_IRR7:
1260 			i = (offset - APIC_OFFSET_IRR0) >> 2;
1261 			reg = &lapic->irr0;
1262 			*data = atomic_load_acq_int(reg + i);
1263 			break;
1264 		case APIC_OFFSET_ESR:
1265 			*data = lapic->esr;
1266 			break;
1267 		case APIC_OFFSET_ICR_LOW:
1268 			*data = lapic->icr_lo;
1269 			if (x2apic(vlapic))
1270 				*data |= (uint64_t)lapic->icr_hi << 32;
1271 			break;
1272 		case APIC_OFFSET_ICR_HI:
1273 			*data = lapic->icr_hi;
1274 			break;
1275 		case APIC_OFFSET_CMCI_LVT:
1276 		case APIC_OFFSET_TIMER_LVT ... APIC_OFFSET_ERROR_LVT:
1277 			*data = vlapic_get_lvt(vlapic, offset);
1278 #ifdef INVARIANTS
1279 			reg = vlapic_get_lvtptr(vlapic, offset);
1280 			KASSERT(*data == *reg, ("inconsistent lvt value at "
1281 			    "offset %#lx: %#lx/%#x", offset, *data, *reg));
1282 #endif
1283 			break;
1284 		case APIC_OFFSET_TIMER_ICR:
1285 			*data = lapic->icr_timer;
1286 			break;
1287 		case APIC_OFFSET_TIMER_CCR:
1288 			*data = vlapic_get_ccr(vlapic);
1289 			break;
1290 		case APIC_OFFSET_TIMER_DCR:
1291 			*data = lapic->dcr_timer;
1292 			break;
1293 		case APIC_OFFSET_SELF_IPI:
1294 			/*
1295 			 * XXX generate a GP fault if vlapic is in x2apic mode
1296 			 */
1297 			*data = 0;
1298 			break;
1299 		case APIC_OFFSET_RRR:
1300 		default:
1301 			*data = 0;
1302 			break;
1303 	}
1304 done:
1305 	VLAPIC_CTR2(vlapic, "vlapic read offset %#x, data %#lx", offset, *data);
1306 	return 0;
1307 }
1308 
1309 int
1310 vlapic_write(struct vlapic *vlapic, int mmio_access, uint64_t offset,
1311     uint64_t data, bool *retu)
1312 {
1313 	struct LAPIC	*lapic = vlapic->apic_page;
1314 	uint32_t	*regptr;
1315 	int		retval;
1316 
1317 	KASSERT((offset & 0xf) == 0 && offset < PAGE_SIZE,
1318 	    ("vlapic_write: invalid offset %#lx", offset));
1319 
1320 	VLAPIC_CTR2(vlapic, "vlapic write offset %#lx, data %#lx",
1321 	    offset, data);
1322 
1323 	if (offset > sizeof(*lapic))
1324 		return (0);
1325 
1326 	/* Ignore MMIO accesses in x2APIC mode */
1327 	if (x2apic(vlapic) && mmio_access) {
1328 		VLAPIC_CTR2(vlapic, "MMIO write of %#lx to offset %#lx "
1329 		    "in x2APIC mode", data, offset);
1330 		return (0);
1331 	}
1332 
1333 	/*
1334 	 * XXX Generate GP fault for MSR accesses in xAPIC mode
1335 	 */
1336 	if (!x2apic(vlapic) && !mmio_access) {
1337 		VLAPIC_CTR2(vlapic, "x2APIC MSR write of %#lx to offset %#lx "
1338 		    "in xAPIC mode", data, offset);
1339 		return (0);
1340 	}
1341 
1342 	retval = 0;
1343 	switch(offset)
1344 	{
1345 		case APIC_OFFSET_ID:
1346 			lapic->id = data;
1347 			vlapic_id_write_handler(vlapic);
1348 			break;
1349 		case APIC_OFFSET_TPR:
1350 			vlapic_set_tpr(vlapic, data & 0xff);
1351 			break;
1352 		case APIC_OFFSET_EOI:
1353 			vlapic_process_eoi(vlapic);
1354 			break;
1355 		case APIC_OFFSET_LDR:
1356 			lapic->ldr = data;
1357 			vlapic_ldr_write_handler(vlapic);
1358 			break;
1359 		case APIC_OFFSET_DFR:
1360 			lapic->dfr = data;
1361 			vlapic_dfr_write_handler(vlapic);
1362 			break;
1363 		case APIC_OFFSET_SVR:
1364 			lapic->svr = data;
1365 			vlapic_svr_write_handler(vlapic);
1366 			break;
1367 		case APIC_OFFSET_ICR_LOW:
1368 			lapic->icr_lo = data;
1369 			if (x2apic(vlapic))
1370 				lapic->icr_hi = data >> 32;
1371 			retval = vlapic_icrlo_write_handler(vlapic, retu);
1372 			break;
1373 		case APIC_OFFSET_ICR_HI:
1374 			lapic->icr_hi = data;
1375 			break;
1376 		case APIC_OFFSET_CMCI_LVT:
1377 		case APIC_OFFSET_TIMER_LVT ... APIC_OFFSET_ERROR_LVT:
1378 			regptr = vlapic_get_lvtptr(vlapic, offset);
1379 			*regptr = data;
1380 			vlapic_lvt_write_handler(vlapic, offset);
1381 			break;
1382 		case APIC_OFFSET_TIMER_ICR:
1383 			lapic->icr_timer = data;
1384 			vlapic_icrtmr_write_handler(vlapic);
1385 			break;
1386 
1387 		case APIC_OFFSET_TIMER_DCR:
1388 			lapic->dcr_timer = data;
1389 			vlapic_dcr_write_handler(vlapic);
1390 			break;
1391 
1392 		case APIC_OFFSET_ESR:
1393 			vlapic_esr_write_handler(vlapic);
1394 			break;
1395 
1396 		case APIC_OFFSET_SELF_IPI:
1397 			if (x2apic(vlapic))
1398 				vlapic_self_ipi_handler(vlapic, data);
1399 			break;
1400 
1401 		case APIC_OFFSET_VER:
1402 		case APIC_OFFSET_APR:
1403 		case APIC_OFFSET_PPR:
1404 		case APIC_OFFSET_RRR:
1405 		case APIC_OFFSET_ISR0 ... APIC_OFFSET_ISR7:
1406 		case APIC_OFFSET_TMR0 ... APIC_OFFSET_TMR7:
1407 		case APIC_OFFSET_IRR0 ... APIC_OFFSET_IRR7:
1408 		case APIC_OFFSET_TIMER_CCR:
1409 		default:
1410 			// Read only.
1411 			break;
1412 	}
1413 
1414 	return (retval);
1415 }
1416 
1417 static void
1418 vlapic_reset(struct vlapic *vlapic)
1419 {
1420 	struct LAPIC *lapic;
1421 
1422 	lapic = vlapic->apic_page;
1423 	bzero(lapic, sizeof(struct LAPIC));
1424 
1425 	lapic->id = vlapic_get_id(vlapic);
1426 	lapic->version = VLAPIC_VERSION;
1427 	lapic->version |= (VLAPIC_MAXLVT_INDEX << MAXLVTSHIFT);
1428 	lapic->dfr = 0xffffffff;
1429 	lapic->svr = APIC_SVR_VECTOR;
1430 	vlapic_mask_lvts(vlapic);
1431 	vlapic_reset_tmr(vlapic);
1432 
1433 	lapic->dcr_timer = 0;
1434 	vlapic_dcr_write_handler(vlapic);
1435 
1436 	if (vlapic->vcpuid == 0)
1437 		vlapic->boot_state = BS_RUNNING;	/* BSP */
1438 	else
1439 		vlapic->boot_state = BS_INIT;		/* AP */
1440 
1441 	vlapic->svr_last = lapic->svr;
1442 }
1443 
1444 void
1445 vlapic_init(struct vlapic *vlapic)
1446 {
1447 	KASSERT(vlapic->vm != NULL, ("vlapic_init: vm is not initialized"));
1448 	KASSERT(vlapic->vcpuid >= 0 && vlapic->vcpuid < VM_MAXCPU,
1449 	    ("vlapic_init: vcpuid is not initialized"));
1450 	KASSERT(vlapic->apic_page != NULL, ("vlapic_init: apic_page is not "
1451 	    "initialized"));
1452 
1453 	/*
1454 	 * If the vlapic is configured in x2apic mode then it will be
1455 	 * accessed in the critical section via the MSR emulation code.
1456 	 *
1457 	 * Therefore the timer mutex must be a spinlock because blockable
1458 	 * mutexes cannot be acquired in a critical section.
1459 	 */
1460 	mtx_init(&vlapic->timer_mtx, "vlapic timer mtx", NULL, MTX_SPIN);
1461 	callout_init(&vlapic->callout, 1);
1462 
1463 	vlapic->msr_apicbase = DEFAULT_APIC_BASE | APICBASE_ENABLED;
1464 
1465 	if (vlapic->vcpuid == 0)
1466 		vlapic->msr_apicbase |= APICBASE_BSP;
1467 
1468 	vlapic_reset(vlapic);
1469 }
1470 
1471 void
1472 vlapic_cleanup(struct vlapic *vlapic)
1473 {
1474 
1475 	callout_drain(&vlapic->callout);
1476 }
1477 
1478 uint64_t
1479 vlapic_get_apicbase(struct vlapic *vlapic)
1480 {
1481 
1482 	return (vlapic->msr_apicbase);
1483 }
1484 
1485 int
1486 vlapic_set_apicbase(struct vlapic *vlapic, uint64_t new)
1487 {
1488 
1489 	if (vlapic->msr_apicbase != new) {
1490 		VLAPIC_CTR2(vlapic, "Changing APIC_BASE MSR from %#lx to %#lx "
1491 		    "not supported", vlapic->msr_apicbase, new);
1492 		return (-1);
1493 	}
1494 
1495 	return (0);
1496 }
1497 
1498 void
1499 vlapic_set_x2apic_state(struct vm *vm, int vcpuid, enum x2apic_state state)
1500 {
1501 	struct vlapic *vlapic;
1502 	struct LAPIC *lapic;
1503 
1504 	vlapic = vm_lapic(vm, vcpuid);
1505 
1506 	if (state == X2APIC_DISABLED)
1507 		vlapic->msr_apicbase &= ~APICBASE_X2APIC;
1508 	else
1509 		vlapic->msr_apicbase |= APICBASE_X2APIC;
1510 
1511 	/*
1512 	 * Reset the local APIC registers whose values are mode-dependent.
1513 	 *
1514 	 * XXX this works because the APIC mode can be changed only at vcpu
1515 	 * initialization time.
1516 	 */
1517 	lapic = vlapic->apic_page;
1518 	lapic->id = vlapic_get_id(vlapic);
1519 	if (x2apic(vlapic)) {
1520 		lapic->ldr = x2apic_ldr(vlapic);
1521 		lapic->dfr = 0;
1522 	} else {
1523 		lapic->ldr = 0;
1524 		lapic->dfr = 0xffffffff;
1525 	}
1526 
1527 	if (state == X2APIC_ENABLED) {
1528 		if (vlapic->ops.enable_x2apic_mode)
1529 			(*vlapic->ops.enable_x2apic_mode)(vlapic);
1530 	}
1531 }
1532 
1533 void
1534 vlapic_deliver_intr(struct vm *vm, bool level, uint32_t dest, bool phys,
1535     int delmode, int vec)
1536 {
1537 	bool lowprio;
1538 	int vcpuid;
1539 	cpuset_t dmask;
1540 
1541 	if (delmode != IOART_DELFIXED &&
1542 	    delmode != IOART_DELLOPRI &&
1543 	    delmode != IOART_DELEXINT) {
1544 		VM_CTR1(vm, "vlapic intr invalid delmode %#x", delmode);
1545 		return;
1546 	}
1547 	lowprio = (delmode == IOART_DELLOPRI);
1548 
1549 	/*
1550 	 * We don't provide any virtual interrupt redirection hardware so
1551 	 * all interrupts originating from the ioapic or MSI specify the
1552 	 * 'dest' in the legacy xAPIC format.
1553 	 */
1554 	vlapic_calcdest(vm, &dmask, dest, phys, lowprio, false);
1555 
1556 	while ((vcpuid = CPU_FFS(&dmask)) != 0) {
1557 		vcpuid--;
1558 		CPU_CLR(vcpuid, &dmask);
1559 		if (delmode == IOART_DELEXINT) {
1560 			vm_inject_extint(vm, vcpuid);
1561 		} else {
1562 			lapic_set_intr(vm, vcpuid, vec, level);
1563 		}
1564 	}
1565 }
1566 
1567 void
1568 vlapic_post_intr(struct vlapic *vlapic, int hostcpu, int ipinum)
1569 {
1570 	/*
1571 	 * Post an interrupt to the vcpu currently running on 'hostcpu'.
1572 	 *
1573 	 * This is done by leveraging features like Posted Interrupts (Intel)
1574 	 * Doorbell MSR (AMD AVIC) that avoid a VM exit.
1575 	 *
1576 	 * If neither of these features are available then fallback to
1577 	 * sending an IPI to 'hostcpu'.
1578 	 */
1579 	if (vlapic->ops.post_intr)
1580 		(*vlapic->ops.post_intr)(vlapic, hostcpu);
1581 	else
1582 		ipi_cpu(hostcpu, ipinum);
1583 }
1584 
1585 bool
1586 vlapic_enabled(struct vlapic *vlapic)
1587 {
1588 	struct LAPIC *lapic = vlapic->apic_page;
1589 
1590 	if ((vlapic->msr_apicbase & APICBASE_ENABLED) != 0 &&
1591 	    (lapic->svr & APIC_SVR_ENABLE) != 0)
1592 		return (true);
1593 	else
1594 		return (false);
1595 }
1596 
1597 static void
1598 vlapic_set_tmr(struct vlapic *vlapic, int vector, bool level)
1599 {
1600 	struct LAPIC *lapic;
1601 	uint32_t *tmrptr, mask;
1602 	int idx;
1603 
1604 	lapic = vlapic->apic_page;
1605 	tmrptr = &lapic->tmr0;
1606 	idx = (vector / 32) * 4;
1607 	mask = 1 << (vector % 32);
1608 	if (level)
1609 		tmrptr[idx] |= mask;
1610 	else
1611 		tmrptr[idx] &= ~mask;
1612 
1613 	if (vlapic->ops.set_tmr != NULL)
1614 		(*vlapic->ops.set_tmr)(vlapic, vector, level);
1615 }
1616 
1617 void
1618 vlapic_reset_tmr(struct vlapic *vlapic)
1619 {
1620 	int vector;
1621 
1622 	VLAPIC_CTR0(vlapic, "vlapic resetting all vectors to edge-triggered");
1623 
1624 	for (vector = 0; vector <= 255; vector++)
1625 		vlapic_set_tmr(vlapic, vector, false);
1626 }
1627 
1628 void
1629 vlapic_set_tmr_level(struct vlapic *vlapic, uint32_t dest, bool phys,
1630     int delmode, int vector)
1631 {
1632 	cpuset_t dmask;
1633 	bool lowprio;
1634 
1635 	KASSERT(vector >= 0 && vector <= 255, ("invalid vector %d", vector));
1636 
1637 	/*
1638 	 * A level trigger is valid only for fixed and lowprio delivery modes.
1639 	 */
1640 	if (delmode != APIC_DELMODE_FIXED && delmode != APIC_DELMODE_LOWPRIO) {
1641 		VLAPIC_CTR1(vlapic, "Ignoring level trigger-mode for "
1642 		    "delivery-mode %d", delmode);
1643 		return;
1644 	}
1645 
1646 	lowprio = (delmode == APIC_DELMODE_LOWPRIO);
1647 	vlapic_calcdest(vlapic->vm, &dmask, dest, phys, lowprio, false);
1648 
1649 	if (!CPU_ISSET(vlapic->vcpuid, &dmask))
1650 		return;
1651 
1652 	VLAPIC_CTR1(vlapic, "vector %d set to level-triggered", vector);
1653 	vlapic_set_tmr(vlapic, vector, true);
1654 }
1655