xref: /freebsd/sys/amd64/vmm/io/vlapic.c (revision b3e7694832e81d7a904a10f525f8797b753bf0d3)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2011 NetApp, Inc.
5  * All rights reserved.
6  * Copyright (c) 2019 Joyent, Inc.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 #include "opt_bhyve_snapshot.h"
34 
35 #include <sys/param.h>
36 #include <sys/lock.h>
37 #include <sys/kernel.h>
38 #include <sys/malloc.h>
39 #include <sys/mutex.h>
40 #include <sys/systm.h>
41 #include <sys/smp.h>
42 
43 #include <x86/specialreg.h>
44 #include <x86/apicreg.h>
45 
46 #include <machine/clock.h>
47 #include <machine/smp.h>
48 
49 #include <machine/vmm.h>
50 #include <machine/vmm_snapshot.h>
51 
52 #include "vmm_lapic.h"
53 #include "vmm_ktr.h"
54 #include "vmm_stat.h"
55 
56 #include "vlapic.h"
57 #include "vlapic_priv.h"
58 #include "vioapic.h"
59 
60 #define	PRIO(x)			((x) >> 4)
61 
62 #define VLAPIC_VERSION		(0x14)
63 
64 #define	x2apic(vlapic)	(((vlapic)->msr_apicbase & APICBASE_X2APIC) ? 1 : 0)
65 
66 /*
67  * The 'vlapic->timer_mtx' is used to provide mutual exclusion between the
68  * vlapic_callout_handler() and vcpu accesses to:
69  * - timer_freq_bt, timer_period_bt, timer_fire_bt
70  * - timer LVT register
71  */
72 #define	VLAPIC_TIMER_LOCK(vlapic)	mtx_lock_spin(&((vlapic)->timer_mtx))
73 #define	VLAPIC_TIMER_UNLOCK(vlapic)	mtx_unlock_spin(&((vlapic)->timer_mtx))
74 #define	VLAPIC_TIMER_LOCKED(vlapic)	mtx_owned(&((vlapic)->timer_mtx))
75 
76 /*
77  * APIC timer frequency:
78  * - arbitrary but chosen to be in the ballpark of contemporary hardware.
79  * - power-of-two to avoid loss of precision when converted to a bintime.
80  */
81 #define VLAPIC_BUS_FREQ		(128 * 1024 * 1024)
82 
83 static void vlapic_set_error(struct vlapic *, uint32_t, bool);
84 static void vlapic_callout_handler(void *arg);
85 static void vlapic_reset(struct vlapic *vlapic);
86 
87 static __inline uint32_t
88 vlapic_get_id(struct vlapic *vlapic)
89 {
90 
91 	if (x2apic(vlapic))
92 		return (vlapic->vcpuid);
93 	else
94 		return (vlapic->vcpuid << 24);
95 }
96 
97 static uint32_t
98 x2apic_ldr(struct vlapic *vlapic)
99 {
100 	int apicid;
101 	uint32_t ldr;
102 
103 	apicid = vlapic_get_id(vlapic);
104 	ldr = 1 << (apicid & 0xf);
105 	ldr |= (apicid & 0xffff0) << 12;
106 	return (ldr);
107 }
108 
109 void
110 vlapic_dfr_write_handler(struct vlapic *vlapic)
111 {
112 	struct LAPIC *lapic;
113 
114 	lapic = vlapic->apic_page;
115 	if (x2apic(vlapic)) {
116 		VM_CTR1(vlapic->vm, "ignoring write to DFR in x2apic mode: %#x",
117 		    lapic->dfr);
118 		lapic->dfr = 0;
119 		return;
120 	}
121 
122 	lapic->dfr &= APIC_DFR_MODEL_MASK;
123 	lapic->dfr |= APIC_DFR_RESERVED;
124 
125 	if ((lapic->dfr & APIC_DFR_MODEL_MASK) == APIC_DFR_MODEL_FLAT)
126 		VLAPIC_CTR0(vlapic, "vlapic DFR in Flat Model");
127 	else if ((lapic->dfr & APIC_DFR_MODEL_MASK) == APIC_DFR_MODEL_CLUSTER)
128 		VLAPIC_CTR0(vlapic, "vlapic DFR in Cluster Model");
129 	else
130 		VLAPIC_CTR1(vlapic, "DFR in Unknown Model %#x", lapic->dfr);
131 }
132 
133 void
134 vlapic_ldr_write_handler(struct vlapic *vlapic)
135 {
136 	struct LAPIC *lapic;
137 
138 	lapic = vlapic->apic_page;
139 
140 	/* LDR is read-only in x2apic mode */
141 	if (x2apic(vlapic)) {
142 		VLAPIC_CTR1(vlapic, "ignoring write to LDR in x2apic mode: %#x",
143 		    lapic->ldr);
144 		lapic->ldr = x2apic_ldr(vlapic);
145 	} else {
146 		lapic->ldr &= ~APIC_LDR_RESERVED;
147 		VLAPIC_CTR1(vlapic, "vlapic LDR set to %#x", lapic->ldr);
148 	}
149 }
150 
151 void
152 vlapic_id_write_handler(struct vlapic *vlapic)
153 {
154 	struct LAPIC *lapic;
155 
156 	/*
157 	 * We don't allow the ID register to be modified so reset it back to
158 	 * its default value.
159 	 */
160 	lapic = vlapic->apic_page;
161 	lapic->id = vlapic_get_id(vlapic);
162 }
163 
164 static int
165 vlapic_timer_divisor(uint32_t dcr)
166 {
167 	switch (dcr & 0xB) {
168 	case APIC_TDCR_1:
169 		return (1);
170 	case APIC_TDCR_2:
171 		return (2);
172 	case APIC_TDCR_4:
173 		return (4);
174 	case APIC_TDCR_8:
175 		return (8);
176 	case APIC_TDCR_16:
177 		return (16);
178 	case APIC_TDCR_32:
179 		return (32);
180 	case APIC_TDCR_64:
181 		return (64);
182 	case APIC_TDCR_128:
183 		return (128);
184 	default:
185 		panic("vlapic_timer_divisor: invalid dcr 0x%08x", dcr);
186 	}
187 }
188 
189 #if 0
190 static inline void
191 vlapic_dump_lvt(uint32_t offset, uint32_t *lvt)
192 {
193 	printf("Offset %x: lvt %08x (V:%02x DS:%x M:%x)\n", offset,
194 	    *lvt, *lvt & APIC_LVTT_VECTOR, *lvt & APIC_LVTT_DS,
195 	    *lvt & APIC_LVTT_M);
196 }
197 #endif
198 
199 static uint32_t
200 vlapic_get_ccr(struct vlapic *vlapic)
201 {
202 	struct bintime bt_now, bt_rem;
203 	struct LAPIC *lapic __diagused;
204 	uint32_t ccr;
205 
206 	ccr = 0;
207 	lapic = vlapic->apic_page;
208 
209 	VLAPIC_TIMER_LOCK(vlapic);
210 	if (callout_active(&vlapic->callout)) {
211 		/*
212 		 * If the timer is scheduled to expire in the future then
213 		 * compute the value of 'ccr' based on the remaining time.
214 		 */
215 		binuptime(&bt_now);
216 		if (bintime_cmp(&vlapic->timer_fire_bt, &bt_now, >)) {
217 			bt_rem = vlapic->timer_fire_bt;
218 			bintime_sub(&bt_rem, &bt_now);
219 			ccr += bt_rem.sec * BT2FREQ(&vlapic->timer_freq_bt);
220 			ccr += bt_rem.frac / vlapic->timer_freq_bt.frac;
221 		}
222 	}
223 	KASSERT(ccr <= lapic->icr_timer, ("vlapic_get_ccr: invalid ccr %#x, "
224 	    "icr_timer is %#x", ccr, lapic->icr_timer));
225 	VLAPIC_CTR2(vlapic, "vlapic ccr_timer = %#x, icr_timer = %#x",
226 	    ccr, lapic->icr_timer);
227 	VLAPIC_TIMER_UNLOCK(vlapic);
228 	return (ccr);
229 }
230 
231 void
232 vlapic_dcr_write_handler(struct vlapic *vlapic)
233 {
234 	struct LAPIC *lapic;
235 	int divisor;
236 
237 	lapic = vlapic->apic_page;
238 	VLAPIC_TIMER_LOCK(vlapic);
239 
240 	divisor = vlapic_timer_divisor(lapic->dcr_timer);
241 	VLAPIC_CTR2(vlapic, "vlapic dcr_timer=%#x, divisor=%d",
242 	    lapic->dcr_timer, divisor);
243 
244 	/*
245 	 * Update the timer frequency and the timer period.
246 	 *
247 	 * XXX changes to the frequency divider will not take effect until
248 	 * the timer is reloaded.
249 	 */
250 	FREQ2BT(VLAPIC_BUS_FREQ / divisor, &vlapic->timer_freq_bt);
251 	vlapic->timer_period_bt = vlapic->timer_freq_bt;
252 	bintime_mul(&vlapic->timer_period_bt, lapic->icr_timer);
253 
254 	VLAPIC_TIMER_UNLOCK(vlapic);
255 }
256 
257 void
258 vlapic_esr_write_handler(struct vlapic *vlapic)
259 {
260 	struct LAPIC *lapic;
261 
262 	lapic = vlapic->apic_page;
263 	lapic->esr = vlapic->esr_pending;
264 	vlapic->esr_pending = 0;
265 }
266 
267 int
268 vlapic_set_intr_ready(struct vlapic *vlapic, int vector, bool level)
269 {
270 	struct LAPIC *lapic;
271 	uint32_t *irrptr, *tmrptr, mask;
272 	int idx;
273 
274 	KASSERT(vector >= 0 && vector < 256, ("invalid vector %d", vector));
275 
276 	lapic = vlapic->apic_page;
277 	if (!(lapic->svr & APIC_SVR_ENABLE)) {
278 		VLAPIC_CTR1(vlapic, "vlapic is software disabled, ignoring "
279 		    "interrupt %d", vector);
280 		return (0);
281 	}
282 
283 	if (vector < 16) {
284 		vlapic_set_error(vlapic, APIC_ESR_RECEIVE_ILLEGAL_VECTOR,
285 		    false);
286 		VLAPIC_CTR1(vlapic, "vlapic ignoring interrupt to vector %d",
287 		    vector);
288 		return (1);
289 	}
290 
291 	if (vlapic->ops.set_intr_ready)
292 		return ((*vlapic->ops.set_intr_ready)(vlapic, vector, level));
293 
294 	idx = (vector / 32) * 4;
295 	mask = 1 << (vector % 32);
296 
297 	irrptr = &lapic->irr0;
298 	atomic_set_int(&irrptr[idx], mask);
299 
300 	/*
301 	 * Verify that the trigger-mode of the interrupt matches with
302 	 * the vlapic TMR registers.
303 	 */
304 	tmrptr = &lapic->tmr0;
305 	if ((tmrptr[idx] & mask) != (level ? mask : 0)) {
306 		VLAPIC_CTR3(vlapic, "vlapic TMR[%d] is 0x%08x but "
307 		    "interrupt is %s-triggered", idx / 4, tmrptr[idx],
308 		    level ? "level" : "edge");
309 	}
310 
311 	VLAPIC_CTR_IRR(vlapic, "vlapic_set_intr_ready");
312 	return (1);
313 }
314 
315 static __inline uint32_t *
316 vlapic_get_lvtptr(struct vlapic *vlapic, uint32_t offset)
317 {
318 	struct LAPIC	*lapic = vlapic->apic_page;
319 	int 		 i;
320 
321 	switch (offset) {
322 	case APIC_OFFSET_CMCI_LVT:
323 		return (&lapic->lvt_cmci);
324 	case APIC_OFFSET_TIMER_LVT ... APIC_OFFSET_ERROR_LVT:
325 		i = (offset - APIC_OFFSET_TIMER_LVT) >> 2;
326 		return ((&lapic->lvt_timer) + i);
327 	default:
328 		panic("vlapic_get_lvt: invalid LVT\n");
329 	}
330 }
331 
332 static __inline int
333 lvt_off_to_idx(uint32_t offset)
334 {
335 	int index;
336 
337 	switch (offset) {
338 	case APIC_OFFSET_CMCI_LVT:
339 		index = APIC_LVT_CMCI;
340 		break;
341 	case APIC_OFFSET_TIMER_LVT:
342 		index = APIC_LVT_TIMER;
343 		break;
344 	case APIC_OFFSET_THERM_LVT:
345 		index = APIC_LVT_THERMAL;
346 		break;
347 	case APIC_OFFSET_PERF_LVT:
348 		index = APIC_LVT_PMC;
349 		break;
350 	case APIC_OFFSET_LINT0_LVT:
351 		index = APIC_LVT_LINT0;
352 		break;
353 	case APIC_OFFSET_LINT1_LVT:
354 		index = APIC_LVT_LINT1;
355 		break;
356 	case APIC_OFFSET_ERROR_LVT:
357 		index = APIC_LVT_ERROR;
358 		break;
359 	default:
360 		index = -1;
361 		break;
362 	}
363 	KASSERT(index >= 0 && index <= VLAPIC_MAXLVT_INDEX, ("lvt_off_to_idx: "
364 	    "invalid lvt index %d for offset %#x", index, offset));
365 
366 	return (index);
367 }
368 
369 static __inline uint32_t
370 vlapic_get_lvt(struct vlapic *vlapic, uint32_t offset)
371 {
372 	int idx;
373 	uint32_t val;
374 
375 	idx = lvt_off_to_idx(offset);
376 	val = atomic_load_acq_32(&vlapic->lvt_last[idx]);
377 	return (val);
378 }
379 
380 void
381 vlapic_lvt_write_handler(struct vlapic *vlapic, uint32_t offset)
382 {
383 	uint32_t *lvtptr, mask, val;
384 	struct LAPIC *lapic;
385 	int idx;
386 
387 	lapic = vlapic->apic_page;
388 	lvtptr = vlapic_get_lvtptr(vlapic, offset);
389 	val = *lvtptr;
390 	idx = lvt_off_to_idx(offset);
391 
392 	if (!(lapic->svr & APIC_SVR_ENABLE))
393 		val |= APIC_LVT_M;
394 	mask = APIC_LVT_M | APIC_LVT_DS | APIC_LVT_VECTOR;
395 	switch (offset) {
396 	case APIC_OFFSET_TIMER_LVT:
397 		mask |= APIC_LVTT_TM;
398 		break;
399 	case APIC_OFFSET_ERROR_LVT:
400 		break;
401 	case APIC_OFFSET_LINT0_LVT:
402 	case APIC_OFFSET_LINT1_LVT:
403 		mask |= APIC_LVT_TM | APIC_LVT_RIRR | APIC_LVT_IIPP;
404 		/* FALLTHROUGH */
405 	default:
406 		mask |= APIC_LVT_DM;
407 		break;
408 	}
409 	val &= mask;
410 	*lvtptr = val;
411 	atomic_store_rel_32(&vlapic->lvt_last[idx], val);
412 }
413 
414 static void
415 vlapic_mask_lvts(struct vlapic *vlapic)
416 {
417 	struct LAPIC *lapic = vlapic->apic_page;
418 
419 	lapic->lvt_cmci |= APIC_LVT_M;
420 	vlapic_lvt_write_handler(vlapic, APIC_OFFSET_CMCI_LVT);
421 
422 	lapic->lvt_timer |= APIC_LVT_M;
423 	vlapic_lvt_write_handler(vlapic, APIC_OFFSET_TIMER_LVT);
424 
425 	lapic->lvt_thermal |= APIC_LVT_M;
426 	vlapic_lvt_write_handler(vlapic, APIC_OFFSET_THERM_LVT);
427 
428 	lapic->lvt_pcint |= APIC_LVT_M;
429 	vlapic_lvt_write_handler(vlapic, APIC_OFFSET_PERF_LVT);
430 
431 	lapic->lvt_lint0 |= APIC_LVT_M;
432 	vlapic_lvt_write_handler(vlapic, APIC_OFFSET_LINT0_LVT);
433 
434 	lapic->lvt_lint1 |= APIC_LVT_M;
435 	vlapic_lvt_write_handler(vlapic, APIC_OFFSET_LINT1_LVT);
436 
437 	lapic->lvt_error |= APIC_LVT_M;
438 	vlapic_lvt_write_handler(vlapic, APIC_OFFSET_ERROR_LVT);
439 }
440 
441 static int
442 vlapic_fire_lvt(struct vlapic *vlapic, u_int lvt)
443 {
444 	uint32_t mode, reg, vec;
445 
446 	reg = atomic_load_acq_32(&vlapic->lvt_last[lvt]);
447 
448 	if (reg & APIC_LVT_M)
449 		return (0);
450 	vec = reg & APIC_LVT_VECTOR;
451 	mode = reg & APIC_LVT_DM;
452 
453 	switch (mode) {
454 	case APIC_LVT_DM_FIXED:
455 		if (vec < 16) {
456 			vlapic_set_error(vlapic, APIC_ESR_SEND_ILLEGAL_VECTOR,
457 			    lvt == APIC_LVT_ERROR);
458 			return (0);
459 		}
460 		if (vlapic_set_intr_ready(vlapic, vec, false))
461 			vcpu_notify_event(vlapic->vcpu, true);
462 		break;
463 	case APIC_LVT_DM_NMI:
464 		vm_inject_nmi(vlapic->vcpu);
465 		break;
466 	case APIC_LVT_DM_EXTINT:
467 		vm_inject_extint(vlapic->vcpu);
468 		break;
469 	default:
470 		// Other modes ignored
471 		return (0);
472 	}
473 	return (1);
474 }
475 
476 #if 1
477 static void
478 dump_isrvec_stk(struct vlapic *vlapic)
479 {
480 	int i;
481 	uint32_t *isrptr;
482 
483 	isrptr = &vlapic->apic_page->isr0;
484 	for (i = 0; i < 8; i++)
485 		printf("ISR%d 0x%08x\n", i, isrptr[i * 4]);
486 
487 	for (i = 0; i <= vlapic->isrvec_stk_top; i++)
488 		printf("isrvec_stk[%d] = %d\n", i, vlapic->isrvec_stk[i]);
489 }
490 #endif
491 
492 /*
493  * Algorithm adopted from section "Interrupt, Task and Processor Priority"
494  * in Intel Architecture Manual Vol 3a.
495  */
496 static void
497 vlapic_update_ppr(struct vlapic *vlapic)
498 {
499 	int isrvec, tpr, ppr;
500 
501 	/*
502 	 * Note that the value on the stack at index 0 is always 0.
503 	 *
504 	 * This is a placeholder for the value of ISRV when none of the
505 	 * bits is set in the ISRx registers.
506 	 */
507 	isrvec = vlapic->isrvec_stk[vlapic->isrvec_stk_top];
508 	tpr = vlapic->apic_page->tpr;
509 
510 #if 1
511 	{
512 		int i, lastprio, curprio, vector, idx;
513 		uint32_t *isrptr;
514 
515 		if (vlapic->isrvec_stk_top == 0 && isrvec != 0)
516 			panic("isrvec_stk is corrupted: %d", isrvec);
517 
518 		/*
519 		 * Make sure that the priority of the nested interrupts is
520 		 * always increasing.
521 		 */
522 		lastprio = -1;
523 		for (i = 1; i <= vlapic->isrvec_stk_top; i++) {
524 			curprio = PRIO(vlapic->isrvec_stk[i]);
525 			if (curprio <= lastprio) {
526 				dump_isrvec_stk(vlapic);
527 				panic("isrvec_stk does not satisfy invariant");
528 			}
529 			lastprio = curprio;
530 		}
531 
532 		/*
533 		 * Make sure that each bit set in the ISRx registers has a
534 		 * corresponding entry on the isrvec stack.
535 		 */
536 		i = 1;
537 		isrptr = &vlapic->apic_page->isr0;
538 		for (vector = 0; vector < 256; vector++) {
539 			idx = (vector / 32) * 4;
540 			if (isrptr[idx] & (1 << (vector % 32))) {
541 				if (i > vlapic->isrvec_stk_top ||
542 				    vlapic->isrvec_stk[i] != vector) {
543 					dump_isrvec_stk(vlapic);
544 					panic("ISR and isrvec_stk out of sync");
545 				}
546 				i++;
547 			}
548 		}
549 	}
550 #endif
551 
552 	if (PRIO(tpr) >= PRIO(isrvec))
553 		ppr = tpr;
554 	else
555 		ppr = isrvec & 0xf0;
556 
557 	vlapic->apic_page->ppr = ppr;
558 	VLAPIC_CTR1(vlapic, "vlapic_update_ppr 0x%02x", ppr);
559 }
560 
561 void
562 vlapic_sync_tpr(struct vlapic *vlapic)
563 {
564 	vlapic_update_ppr(vlapic);
565 }
566 
567 static VMM_STAT(VLAPIC_GRATUITOUS_EOI, "EOI without any in-service interrupt");
568 
569 static void
570 vlapic_process_eoi(struct vlapic *vlapic)
571 {
572 	struct LAPIC	*lapic = vlapic->apic_page;
573 	uint32_t	*isrptr, *tmrptr;
574 	int		i, idx, bitpos, vector;
575 
576 	isrptr = &lapic->isr0;
577 	tmrptr = &lapic->tmr0;
578 
579 	for (i = 7; i >= 0; i--) {
580 		idx = i * 4;
581 		bitpos = fls(isrptr[idx]);
582 		if (bitpos-- != 0) {
583 			if (vlapic->isrvec_stk_top <= 0) {
584 				panic("invalid vlapic isrvec_stk_top %d",
585 				      vlapic->isrvec_stk_top);
586 			}
587 			isrptr[idx] &= ~(1 << bitpos);
588 			vector = i * 32 + bitpos;
589 			VLAPIC_CTR1(vlapic, "EOI vector %d", vector);
590 			VLAPIC_CTR_ISR(vlapic, "vlapic_process_eoi");
591 			vlapic->isrvec_stk_top--;
592 			vlapic_update_ppr(vlapic);
593 			if ((tmrptr[idx] & (1 << bitpos)) != 0) {
594 				vioapic_process_eoi(vlapic->vm, vector);
595 			}
596 			return;
597 		}
598 	}
599 	VLAPIC_CTR0(vlapic, "Gratuitous EOI");
600 	vmm_stat_incr(vlapic->vcpu, VLAPIC_GRATUITOUS_EOI, 1);
601 }
602 
603 static __inline int
604 vlapic_get_lvt_field(uint32_t lvt, uint32_t mask)
605 {
606 
607 	return (lvt & mask);
608 }
609 
610 static __inline int
611 vlapic_periodic_timer(struct vlapic *vlapic)
612 {
613 	uint32_t lvt;
614 
615 	lvt = vlapic_get_lvt(vlapic, APIC_OFFSET_TIMER_LVT);
616 
617 	return (vlapic_get_lvt_field(lvt, APIC_LVTT_TM_PERIODIC));
618 }
619 
620 static VMM_STAT(VLAPIC_INTR_ERROR, "error interrupts generated by vlapic");
621 
622 static void
623 vlapic_set_error(struct vlapic *vlapic, uint32_t mask, bool lvt_error)
624 {
625 
626 	vlapic->esr_pending |= mask;
627 
628 	/*
629 	 * Avoid infinite recursion if the error LVT itself is configured with
630 	 * an illegal vector.
631 	 */
632 	if (lvt_error)
633 		return;
634 
635 	if (vlapic_fire_lvt(vlapic, APIC_LVT_ERROR)) {
636 		vmm_stat_incr(vlapic->vcpu, VLAPIC_INTR_ERROR, 1);
637 	}
638 }
639 
640 static VMM_STAT(VLAPIC_INTR_TIMER, "timer interrupts generated by vlapic");
641 
642 static void
643 vlapic_fire_timer(struct vlapic *vlapic)
644 {
645 
646 	KASSERT(VLAPIC_TIMER_LOCKED(vlapic), ("vlapic_fire_timer not locked"));
647 
648 	if (vlapic_fire_lvt(vlapic, APIC_LVT_TIMER)) {
649 		VLAPIC_CTR0(vlapic, "vlapic timer fired");
650 		vmm_stat_incr(vlapic->vcpu, VLAPIC_INTR_TIMER, 1);
651 	}
652 }
653 
654 static VMM_STAT(VLAPIC_INTR_CMC,
655     "corrected machine check interrupts generated by vlapic");
656 
657 void
658 vlapic_fire_cmci(struct vlapic *vlapic)
659 {
660 
661 	if (vlapic_fire_lvt(vlapic, APIC_LVT_CMCI)) {
662 		vmm_stat_incr(vlapic->vcpu, VLAPIC_INTR_CMC, 1);
663 	}
664 }
665 
666 static VMM_STAT_ARRAY(LVTS_TRIGGERRED, VLAPIC_MAXLVT_INDEX + 1,
667     "lvts triggered");
668 
669 int
670 vlapic_trigger_lvt(struct vlapic *vlapic, int vector)
671 {
672 
673 	if (vlapic_enabled(vlapic) == false) {
674 		/*
675 		 * When the local APIC is global/hardware disabled,
676 		 * LINT[1:0] pins are configured as INTR and NMI pins,
677 		 * respectively.
678 		*/
679 		switch (vector) {
680 			case APIC_LVT_LINT0:
681 				vm_inject_extint(vlapic->vcpu);
682 				break;
683 			case APIC_LVT_LINT1:
684 				vm_inject_nmi(vlapic->vcpu);
685 				break;
686 			default:
687 				break;
688 		}
689 		return (0);
690 	}
691 
692 	switch (vector) {
693 	case APIC_LVT_LINT0:
694 	case APIC_LVT_LINT1:
695 	case APIC_LVT_TIMER:
696 	case APIC_LVT_ERROR:
697 	case APIC_LVT_PMC:
698 	case APIC_LVT_THERMAL:
699 	case APIC_LVT_CMCI:
700 		if (vlapic_fire_lvt(vlapic, vector)) {
701 			vmm_stat_array_incr(vlapic->vcpu, LVTS_TRIGGERRED,
702 			    vector, 1);
703 		}
704 		break;
705 	default:
706 		return (EINVAL);
707 	}
708 	return (0);
709 }
710 
711 static void
712 vlapic_callout_reset(struct vlapic *vlapic, sbintime_t t)
713 {
714 	callout_reset_sbt_curcpu(&vlapic->callout, t, 0,
715 	    vlapic_callout_handler, vlapic, 0);
716 }
717 
718 static void
719 vlapic_callout_handler(void *arg)
720 {
721 	struct vlapic *vlapic;
722 	struct bintime bt, btnow;
723 	sbintime_t rem_sbt;
724 
725 	vlapic = arg;
726 
727 	VLAPIC_TIMER_LOCK(vlapic);
728 	if (callout_pending(&vlapic->callout))	/* callout was reset */
729 		goto done;
730 
731 	if (!callout_active(&vlapic->callout))	/* callout was stopped */
732 		goto done;
733 
734 	callout_deactivate(&vlapic->callout);
735 
736 	vlapic_fire_timer(vlapic);
737 
738 	if (vlapic_periodic_timer(vlapic)) {
739 		binuptime(&btnow);
740 		KASSERT(bintime_cmp(&btnow, &vlapic->timer_fire_bt, >=),
741 		    ("vlapic callout at %#lx.%#lx, expected at %#lx.#%lx",
742 		    btnow.sec, btnow.frac, vlapic->timer_fire_bt.sec,
743 		    vlapic->timer_fire_bt.frac));
744 
745 		/*
746 		 * Compute the delta between when the timer was supposed to
747 		 * fire and the present time.
748 		 */
749 		bt = btnow;
750 		bintime_sub(&bt, &vlapic->timer_fire_bt);
751 
752 		rem_sbt = bttosbt(vlapic->timer_period_bt);
753 		if (bintime_cmp(&bt, &vlapic->timer_period_bt, <)) {
754 			/*
755 			 * Adjust the time until the next countdown downward
756 			 * to account for the lost time.
757 			 */
758 			rem_sbt -= bttosbt(bt);
759 		} else {
760 			/*
761 			 * If the delta is greater than the timer period then
762 			 * just reset our time base instead of trying to catch
763 			 * up.
764 			 */
765 			vlapic->timer_fire_bt = btnow;
766 			VLAPIC_CTR2(vlapic, "vlapic timer lagging by %lu "
767 			    "usecs, period is %lu usecs - resetting time base",
768 			    bttosbt(bt) / SBT_1US,
769 			    bttosbt(vlapic->timer_period_bt) / SBT_1US);
770 		}
771 
772 		bintime_add(&vlapic->timer_fire_bt, &vlapic->timer_period_bt);
773 		vlapic_callout_reset(vlapic, rem_sbt);
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 		vlapic_callout_reset(vlapic, sbt);
800 	} else
801 		callout_stop(&vlapic->callout);
802 
803 	VLAPIC_TIMER_UNLOCK(vlapic);
804 }
805 
806 /*
807  * This function populates 'dmask' with the set of vcpus that match the
808  * addressing specified by the (dest, phys, lowprio) tuple.
809  *
810  * 'x2apic_dest' specifies whether 'dest' is interpreted as x2APIC (32-bit)
811  * or xAPIC (8-bit) destination field.
812  */
813 static void
814 vlapic_calcdest(struct vm *vm, cpuset_t *dmask, uint32_t dest, bool phys,
815     bool lowprio, bool x2apic_dest)
816 {
817 	struct vlapic *vlapic;
818 	uint32_t dfr, ldr, ldest, cluster;
819 	uint32_t mda_flat_ldest, mda_cluster_ldest, mda_ldest, mda_cluster_id;
820 	cpuset_t amask;
821 	int vcpuid;
822 
823 	if ((x2apic_dest && dest == 0xffffffff) ||
824 	    (!x2apic_dest && dest == 0xff)) {
825 		/*
826 		 * Broadcast in both logical and physical modes.
827 		 */
828 		*dmask = vm_active_cpus(vm);
829 		return;
830 	}
831 
832 	if (phys) {
833 		/*
834 		 * Physical mode: destination is APIC ID.
835 		 */
836 		CPU_ZERO(dmask);
837 		vcpuid = vm_apicid2vcpuid(vm, dest);
838 		amask = vm_active_cpus(vm);
839 		if (vcpuid < vm_get_maxcpus(vm) && CPU_ISSET(vcpuid, &amask))
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 available 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 its LDR that matches a bit in the ldest.
863 		 */
864 		CPU_ZERO(dmask);
865 		amask = vm_active_cpus(vm);
866 		CPU_FOREACH_ISSET(vcpuid, &amask) {
867 			vlapic = vm_lapic(vm_vcpu(vm, vcpuid));
868 			dfr = vlapic->apic_page->dfr;
869 			ldr = vlapic->apic_page->ldr;
870 
871 			if ((dfr & APIC_DFR_MODEL_MASK) ==
872 			    APIC_DFR_MODEL_FLAT) {
873 				ldest = ldr >> 24;
874 				mda_ldest = mda_flat_ldest;
875 			} else if ((dfr & APIC_DFR_MODEL_MASK) ==
876 			    APIC_DFR_MODEL_CLUSTER) {
877 				if (x2apic(vlapic)) {
878 					cluster = ldr >> 16;
879 					ldest = ldr & 0xffff;
880 				} else {
881 					cluster = ldr >> 28;
882 					ldest = (ldr >> 24) & 0xf;
883 				}
884 				if (cluster != mda_cluster_id)
885 					continue;
886 				mda_ldest = mda_cluster_ldest;
887 			} else {
888 				/*
889 				 * Guest has configured a bad logical
890 				 * model for this vcpu - skip it.
891 				 */
892 				VLAPIC_CTR1(vlapic, "vlapic has bad logical "
893 				    "model %x - cannot deliver interrupt", dfr);
894 				continue;
895 			}
896 
897 			if ((mda_ldest & ldest) != 0) {
898 				CPU_SET(vcpuid, dmask);
899 				if (lowprio)
900 					break;
901 			}
902 		}
903 	}
904 }
905 
906 static VMM_STAT(VLAPIC_IPI_SEND, "ipis sent from vcpu");
907 static VMM_STAT(VLAPIC_IPI_RECV, "ipis received by vcpu");
908 
909 static void
910 vlapic_set_tpr(struct vlapic *vlapic, uint8_t val)
911 {
912 	struct LAPIC *lapic = vlapic->apic_page;
913 
914 	if (lapic->tpr != val) {
915 		VLAPIC_CTR2(vlapic, "vlapic TPR changed from %#x to %#x",
916 		    lapic->tpr, val);
917 		lapic->tpr = val;
918 		vlapic_update_ppr(vlapic);
919 	}
920 }
921 
922 static uint8_t
923 vlapic_get_tpr(struct vlapic *vlapic)
924 {
925 	struct LAPIC *lapic = vlapic->apic_page;
926 
927 	return (lapic->tpr);
928 }
929 
930 void
931 vlapic_set_cr8(struct vlapic *vlapic, uint64_t val)
932 {
933 	uint8_t tpr;
934 
935 	if (val & ~0xf) {
936 		vm_inject_gp(vlapic->vcpu);
937 		return;
938 	}
939 
940 	tpr = val << 4;
941 	vlapic_set_tpr(vlapic, tpr);
942 }
943 
944 uint64_t
945 vlapic_get_cr8(struct vlapic *vlapic)
946 {
947 	uint8_t tpr;
948 
949 	tpr = vlapic_get_tpr(vlapic);
950 	return (tpr >> 4);
951 }
952 
953 static bool
954 vlapic_is_icr_valid(uint64_t icrval)
955 {
956 	uint32_t mode = icrval & APIC_DELMODE_MASK;
957 	uint32_t level = icrval & APIC_LEVEL_MASK;
958 	uint32_t trigger = icrval & APIC_TRIGMOD_MASK;
959 	uint32_t shorthand = icrval & APIC_DEST_MASK;
960 
961 	switch (mode) {
962 	case APIC_DELMODE_FIXED:
963 		if (trigger == APIC_TRIGMOD_EDGE)
964 			return (true);
965 		/*
966 		 * AMD allows a level assert IPI and Intel converts a level
967 		 * assert IPI into an edge IPI.
968 		 */
969 		if (trigger == APIC_TRIGMOD_LEVEL && level == APIC_LEVEL_ASSERT)
970 			return (true);
971 		break;
972 	case APIC_DELMODE_LOWPRIO:
973 	case APIC_DELMODE_SMI:
974 	case APIC_DELMODE_NMI:
975 	case APIC_DELMODE_INIT:
976 		if (trigger == APIC_TRIGMOD_EDGE &&
977 		    (shorthand == APIC_DEST_DESTFLD ||
978 			shorthand == APIC_DEST_ALLESELF))
979 			return (true);
980 		/*
981 		 * AMD allows a level assert IPI and Intel converts a level
982 		 * assert IPI into an edge IPI.
983 		 */
984 		if (trigger == APIC_TRIGMOD_LEVEL &&
985 		    level == APIC_LEVEL_ASSERT &&
986 		    (shorthand == APIC_DEST_DESTFLD ||
987 			shorthand == APIC_DEST_ALLESELF))
988 			return (true);
989 		/*
990 		 * An level triggered deassert INIT is defined in the Intel
991 		 * Multiprocessor Specification and the Intel Software Developer
992 		 * Manual. Due to the MPS it's required to send a level assert
993 		 * INIT to a cpu and then a level deassert INIT. Some operating
994 		 * systems e.g. FreeBSD or Linux use that algorithm. According
995 		 * to the SDM a level deassert INIT is only supported by Pentium
996 		 * and P6 processors. It's always send to all cpus regardless of
997 		 * the destination or shorthand field. It resets the arbitration
998 		 * id register. This register is not software accessible and
999 		 * only required for the APIC bus arbitration. So, the level
1000 		 * deassert INIT doesn't need any emulation and we should ignore
1001 		 * it. The SDM also defines that newer processors don't support
1002 		 * the level deassert INIT and it's not valid any more. As it's
1003 		 * defined for older systems, it can't be invalid per se.
1004 		 * Otherwise, backward compatibility would be broken. However,
1005 		 * when returning false here, it'll be ignored which is the
1006 		 * desired behaviour.
1007 		 */
1008 		if (mode == APIC_DELMODE_INIT &&
1009 		    trigger == APIC_TRIGMOD_LEVEL &&
1010 		    level == APIC_LEVEL_DEASSERT)
1011 			return (false);
1012 		break;
1013 	case APIC_DELMODE_STARTUP:
1014 		if (shorthand == APIC_DEST_DESTFLD ||
1015 		    shorthand == APIC_DEST_ALLESELF)
1016 			return (true);
1017 		break;
1018 	case APIC_DELMODE_RR:
1019 		/* Only available on AMD! */
1020 		if (trigger == APIC_TRIGMOD_EDGE &&
1021 		    shorthand == APIC_DEST_DESTFLD)
1022 			return (true);
1023 		break;
1024 	case APIC_DELMODE_RESV:
1025 		return (false);
1026 	default:
1027 		__assert_unreachable();
1028 	}
1029 
1030 	return (false);
1031 }
1032 
1033 int
1034 vlapic_icrlo_write_handler(struct vlapic *vlapic, bool *retu)
1035 {
1036 	int i;
1037 	bool phys;
1038 	cpuset_t dmask, ipimask;
1039 	uint64_t icrval;
1040 	uint32_t dest, vec, mode, shorthand;
1041 	struct vcpu *vcpu;
1042 	struct vm_exit *vmexit;
1043 	struct LAPIC *lapic;
1044 
1045 	lapic = vlapic->apic_page;
1046 	lapic->icr_lo &= ~APIC_DELSTAT_PEND;
1047 	icrval = ((uint64_t)lapic->icr_hi << 32) | lapic->icr_lo;
1048 
1049 	if (x2apic(vlapic))
1050 		dest = icrval >> 32;
1051 	else
1052 		dest = icrval >> (32 + 24);
1053 	vec = icrval & APIC_VECTOR_MASK;
1054 	mode = icrval & APIC_DELMODE_MASK;
1055 	phys = (icrval & APIC_DESTMODE_LOG) == 0;
1056 	shorthand = icrval & APIC_DEST_MASK;
1057 
1058 	VLAPIC_CTR2(vlapic, "icrlo 0x%016lx triggered ipi %d", icrval, vec);
1059 
1060 	switch (shorthand) {
1061 	case APIC_DEST_DESTFLD:
1062 		vlapic_calcdest(vlapic->vm, &dmask, dest, phys, false, x2apic(vlapic));
1063 		break;
1064 	case APIC_DEST_SELF:
1065 		CPU_SETOF(vlapic->vcpuid, &dmask);
1066 		break;
1067 	case APIC_DEST_ALLISELF:
1068 		dmask = vm_active_cpus(vlapic->vm);
1069 		break;
1070 	case APIC_DEST_ALLESELF:
1071 		dmask = vm_active_cpus(vlapic->vm);
1072 		CPU_CLR(vlapic->vcpuid, &dmask);
1073 		break;
1074 	default:
1075 		__assert_unreachable();
1076 	}
1077 
1078 	/*
1079 	 * Ignore invalid combinations of the icr.
1080 	 */
1081 	if (!vlapic_is_icr_valid(icrval)) {
1082 		VLAPIC_CTR1(vlapic, "Ignoring invalid ICR %016lx", icrval);
1083 		return (0);
1084 	}
1085 
1086 	/*
1087 	 * ipimask is a set of vCPUs needing userland handling of the current
1088 	 * IPI.
1089 	 */
1090 	CPU_ZERO(&ipimask);
1091 
1092 	switch (mode) {
1093 	case APIC_DELMODE_FIXED:
1094 		if (vec < 16) {
1095 			vlapic_set_error(vlapic, APIC_ESR_SEND_ILLEGAL_VECTOR,
1096 			    false);
1097 			VLAPIC_CTR1(vlapic, "Ignoring invalid IPI %d", vec);
1098 			return (0);
1099 		}
1100 
1101 		CPU_FOREACH_ISSET(i, &dmask) {
1102 			vcpu = vm_vcpu(vlapic->vm, i);
1103 			lapic_intr_edge(vcpu, vec);
1104 			vmm_stat_incr(vlapic->vcpu, VLAPIC_IPI_SEND, 1);
1105 			vmm_stat_incr(vcpu, VLAPIC_IPI_RECV, 1);
1106 			VLAPIC_CTR2(vlapic,
1107 			    "vlapic sending ipi %d to vcpuid %d", vec, i);
1108 		}
1109 
1110 		break;
1111 	case APIC_DELMODE_NMI:
1112 		CPU_FOREACH_ISSET(i, &dmask) {
1113 			vcpu = vm_vcpu(vlapic->vm, i);
1114 			vm_inject_nmi(vcpu);
1115 			VLAPIC_CTR1(vlapic,
1116 			    "vlapic sending ipi nmi to vcpuid %d", i);
1117 		}
1118 
1119 		break;
1120 	case APIC_DELMODE_INIT:
1121 	case APIC_DELMODE_STARTUP:
1122 		if (!vlapic->ipi_exit) {
1123 			if (!phys)
1124 				break;
1125 
1126 			i = vm_apicid2vcpuid(vlapic->vm, dest);
1127 			if (i >= vm_get_maxcpus(vlapic->vm) ||
1128 			    i == vlapic->vcpuid)
1129 				break;
1130 
1131 			CPU_SETOF(i, &ipimask);
1132 
1133 			break;
1134 		}
1135 
1136 		CPU_COPY(&dmask, &ipimask);
1137 		break;
1138 	default:
1139 		return (1);
1140 	}
1141 
1142 	if (!CPU_EMPTY(&ipimask)) {
1143 		vmexit = vm_exitinfo(vlapic->vcpu);
1144 		vmexit->exitcode = VM_EXITCODE_IPI;
1145 		vmexit->u.ipi.mode = mode;
1146 		vmexit->u.ipi.vector = vec;
1147 		*vm_exitinfo_cpuset(vlapic->vcpu) = ipimask;
1148 
1149 		*retu = true;
1150 	}
1151 
1152 	return (0);
1153 }
1154 
1155 static void
1156 vlapic_handle_init(struct vcpu *vcpu, void *arg)
1157 {
1158 	struct vlapic *vlapic = vm_lapic(vcpu);
1159 
1160 	vlapic_reset(vlapic);
1161 }
1162 
1163 int
1164 vm_handle_ipi(struct vcpu *vcpu, struct vm_exit *vme, bool *retu)
1165 {
1166 	struct vlapic *vlapic = vm_lapic(vcpu);
1167 	cpuset_t *dmask = vm_exitinfo_cpuset(vcpu);
1168 	uint8_t vec = vme->u.ipi.vector;
1169 
1170 	*retu = true;
1171 	switch (vme->u.ipi.mode) {
1172 	case APIC_DELMODE_INIT: {
1173 		cpuset_t active, reinit;
1174 
1175 		active = vm_active_cpus(vcpu_vm(vcpu));
1176 		CPU_AND(&reinit, &active, dmask);
1177 		if (!CPU_EMPTY(&reinit)) {
1178 			vm_smp_rendezvous(vcpu, reinit, vlapic_handle_init,
1179 			    NULL);
1180 		}
1181 		vm_await_start(vcpu_vm(vcpu), dmask);
1182 
1183 		if (!vlapic->ipi_exit)
1184 			*retu = false;
1185 
1186 		break;
1187 	}
1188 	case APIC_DELMODE_STARTUP:
1189 		/*
1190 		 * Ignore SIPIs in any state other than wait-for-SIPI
1191 		 */
1192 		*dmask = vm_start_cpus(vcpu_vm(vcpu), dmask);
1193 
1194 		if (CPU_EMPTY(dmask)) {
1195 			*retu = false;
1196 			break;
1197 		}
1198 
1199 		/*
1200 		 * Old bhyve versions don't support the IPI
1201 		 * exit. Translate it into the old style.
1202 		 */
1203 		if (!vlapic->ipi_exit) {
1204 			vme->exitcode = VM_EXITCODE_SPINUP_AP;
1205 			vme->u.spinup_ap.vcpu = CPU_FFS(dmask) - 1;
1206 			vme->u.spinup_ap.rip = vec << PAGE_SHIFT;
1207 		}
1208 
1209 		break;
1210 	default:
1211 		__assert_unreachable();
1212 	}
1213 
1214 	return (0);
1215 }
1216 
1217 void
1218 vlapic_self_ipi_handler(struct vlapic *vlapic, uint64_t val)
1219 {
1220 	int vec;
1221 
1222 	KASSERT(x2apic(vlapic), ("SELF_IPI does not exist in xAPIC mode"));
1223 
1224 	vec = val & 0xff;
1225 	lapic_intr_edge(vlapic->vcpu, vec);
1226 	vmm_stat_incr(vlapic->vcpu, VLAPIC_IPI_SEND, 1);
1227 	vmm_stat_incr(vlapic->vcpu, VLAPIC_IPI_RECV, 1);
1228 	VLAPIC_CTR1(vlapic, "vlapic self-ipi %d", vec);
1229 }
1230 
1231 int
1232 vlapic_pending_intr(struct vlapic *vlapic, int *vecptr)
1233 {
1234 	struct LAPIC	*lapic = vlapic->apic_page;
1235 	int	  	 idx, i, bitpos, vector;
1236 	uint32_t	*irrptr, val;
1237 
1238 	vlapic_update_ppr(vlapic);
1239 
1240 	if (vlapic->ops.pending_intr)
1241 		return ((*vlapic->ops.pending_intr)(vlapic, vecptr));
1242 
1243 	irrptr = &lapic->irr0;
1244 
1245 	for (i = 7; i >= 0; i--) {
1246 		idx = i * 4;
1247 		val = atomic_load_acq_int(&irrptr[idx]);
1248 		bitpos = fls(val);
1249 		if (bitpos != 0) {
1250 			vector = i * 32 + (bitpos - 1);
1251 			if (PRIO(vector) > PRIO(lapic->ppr)) {
1252 				VLAPIC_CTR1(vlapic, "pending intr %d", vector);
1253 				if (vecptr != NULL)
1254 					*vecptr = vector;
1255 				return (1);
1256 			} else
1257 				break;
1258 		}
1259 	}
1260 	return (0);
1261 }
1262 
1263 void
1264 vlapic_intr_accepted(struct vlapic *vlapic, int vector)
1265 {
1266 	struct LAPIC	*lapic = vlapic->apic_page;
1267 	uint32_t	*irrptr, *isrptr;
1268 	int		idx, stk_top;
1269 
1270 	if (vlapic->ops.intr_accepted)
1271 		return ((*vlapic->ops.intr_accepted)(vlapic, vector));
1272 
1273 	/*
1274 	 * clear the ready bit for vector being accepted in irr
1275 	 * and set the vector as in service in isr.
1276 	 */
1277 	idx = (vector / 32) * 4;
1278 
1279 	irrptr = &lapic->irr0;
1280 	atomic_clear_int(&irrptr[idx], 1 << (vector % 32));
1281 	VLAPIC_CTR_IRR(vlapic, "vlapic_intr_accepted");
1282 
1283 	isrptr = &lapic->isr0;
1284 	isrptr[idx] |= 1 << (vector % 32);
1285 	VLAPIC_CTR_ISR(vlapic, "vlapic_intr_accepted");
1286 
1287 	/*
1288 	 * Update the PPR
1289 	 */
1290 	vlapic->isrvec_stk_top++;
1291 
1292 	stk_top = vlapic->isrvec_stk_top;
1293 	if (stk_top >= ISRVEC_STK_SIZE)
1294 		panic("isrvec_stk_top overflow %d", stk_top);
1295 
1296 	vlapic->isrvec_stk[stk_top] = vector;
1297 }
1298 
1299 void
1300 vlapic_svr_write_handler(struct vlapic *vlapic)
1301 {
1302 	struct LAPIC *lapic;
1303 	uint32_t old, new, changed;
1304 
1305 	lapic = vlapic->apic_page;
1306 
1307 	new = lapic->svr;
1308 	old = vlapic->svr_last;
1309 	vlapic->svr_last = new;
1310 
1311 	changed = old ^ new;
1312 	if ((changed & APIC_SVR_ENABLE) != 0) {
1313 		if ((new & APIC_SVR_ENABLE) == 0) {
1314 			/*
1315 			 * The apic is now disabled so stop the apic timer
1316 			 * and mask all the LVT entries.
1317 			 */
1318 			VLAPIC_CTR0(vlapic, "vlapic is software-disabled");
1319 			VLAPIC_TIMER_LOCK(vlapic);
1320 			callout_stop(&vlapic->callout);
1321 			VLAPIC_TIMER_UNLOCK(vlapic);
1322 			vlapic_mask_lvts(vlapic);
1323 		} else {
1324 			/*
1325 			 * The apic is now enabled so restart the apic timer
1326 			 * if it is configured in periodic mode.
1327 			 */
1328 			VLAPIC_CTR0(vlapic, "vlapic is software-enabled");
1329 			if (vlapic_periodic_timer(vlapic))
1330 				vlapic_icrtmr_write_handler(vlapic);
1331 		}
1332 	}
1333 }
1334 
1335 int
1336 vlapic_read(struct vlapic *vlapic, int mmio_access, uint64_t offset,
1337     uint64_t *data, bool *retu)
1338 {
1339 	struct LAPIC	*lapic = vlapic->apic_page;
1340 	uint32_t	*reg;
1341 	int		 i;
1342 
1343 	/* Ignore MMIO accesses in x2APIC mode */
1344 	if (x2apic(vlapic) && mmio_access) {
1345 		VLAPIC_CTR1(vlapic, "MMIO read from offset %#lx in x2APIC mode",
1346 		    offset);
1347 		*data = 0;
1348 		goto done;
1349 	}
1350 
1351 	if (!x2apic(vlapic) && !mmio_access) {
1352 		/*
1353 		 * XXX Generate GP fault for MSR accesses in xAPIC mode
1354 		 */
1355 		VLAPIC_CTR1(vlapic, "x2APIC MSR read from offset %#lx in "
1356 		    "xAPIC mode", offset);
1357 		*data = 0;
1358 		goto done;
1359 	}
1360 
1361 	if (offset > sizeof(*lapic)) {
1362 		*data = 0;
1363 		goto done;
1364 	}
1365 
1366 	offset &= ~3;
1367 	switch(offset)
1368 	{
1369 		case APIC_OFFSET_ID:
1370 			*data = lapic->id;
1371 			break;
1372 		case APIC_OFFSET_VER:
1373 			*data = lapic->version;
1374 			break;
1375 		case APIC_OFFSET_TPR:
1376 			*data = vlapic_get_tpr(vlapic);
1377 			break;
1378 		case APIC_OFFSET_APR:
1379 			*data = lapic->apr;
1380 			break;
1381 		case APIC_OFFSET_PPR:
1382 			*data = lapic->ppr;
1383 			break;
1384 		case APIC_OFFSET_EOI:
1385 			*data = lapic->eoi;
1386 			break;
1387 		case APIC_OFFSET_LDR:
1388 			*data = lapic->ldr;
1389 			break;
1390 		case APIC_OFFSET_DFR:
1391 			*data = lapic->dfr;
1392 			break;
1393 		case APIC_OFFSET_SVR:
1394 			*data = lapic->svr;
1395 			break;
1396 		case APIC_OFFSET_ISR0 ... APIC_OFFSET_ISR7:
1397 			i = (offset - APIC_OFFSET_ISR0) >> 2;
1398 			reg = &lapic->isr0;
1399 			*data = *(reg + i);
1400 			break;
1401 		case APIC_OFFSET_TMR0 ... APIC_OFFSET_TMR7:
1402 			i = (offset - APIC_OFFSET_TMR0) >> 2;
1403 			reg = &lapic->tmr0;
1404 			*data = *(reg + i);
1405 			break;
1406 		case APIC_OFFSET_IRR0 ... APIC_OFFSET_IRR7:
1407 			i = (offset - APIC_OFFSET_IRR0) >> 2;
1408 			reg = &lapic->irr0;
1409 			*data = atomic_load_acq_int(reg + i);
1410 			break;
1411 		case APIC_OFFSET_ESR:
1412 			*data = lapic->esr;
1413 			break;
1414 		case APIC_OFFSET_ICR_LOW:
1415 			*data = lapic->icr_lo;
1416 			if (x2apic(vlapic))
1417 				*data |= (uint64_t)lapic->icr_hi << 32;
1418 			break;
1419 		case APIC_OFFSET_ICR_HI:
1420 			*data = lapic->icr_hi;
1421 			break;
1422 		case APIC_OFFSET_CMCI_LVT:
1423 		case APIC_OFFSET_TIMER_LVT ... APIC_OFFSET_ERROR_LVT:
1424 			*data = vlapic_get_lvt(vlapic, offset);
1425 #ifdef INVARIANTS
1426 			reg = vlapic_get_lvtptr(vlapic, offset);
1427 			KASSERT(*data == *reg, ("inconsistent lvt value at "
1428 			    "offset %#lx: %#lx/%#x", offset, *data, *reg));
1429 #endif
1430 			break;
1431 		case APIC_OFFSET_TIMER_ICR:
1432 			*data = lapic->icr_timer;
1433 			break;
1434 		case APIC_OFFSET_TIMER_CCR:
1435 			*data = vlapic_get_ccr(vlapic);
1436 			break;
1437 		case APIC_OFFSET_TIMER_DCR:
1438 			*data = lapic->dcr_timer;
1439 			break;
1440 		case APIC_OFFSET_SELF_IPI:
1441 			/*
1442 			 * XXX generate a GP fault if vlapic is in x2apic mode
1443 			 */
1444 			*data = 0;
1445 			break;
1446 		case APIC_OFFSET_RRR:
1447 		default:
1448 			*data = 0;
1449 			break;
1450 	}
1451 done:
1452 	VLAPIC_CTR2(vlapic, "vlapic read offset %#x, data %#lx", offset, *data);
1453 	return 0;
1454 }
1455 
1456 int
1457 vlapic_write(struct vlapic *vlapic, int mmio_access, uint64_t offset,
1458     uint64_t data, bool *retu)
1459 {
1460 	struct LAPIC	*lapic = vlapic->apic_page;
1461 	uint32_t	*regptr;
1462 	int		retval;
1463 
1464 	KASSERT((offset & 0xf) == 0 && offset < PAGE_SIZE,
1465 	    ("vlapic_write: invalid offset %#lx", offset));
1466 
1467 	VLAPIC_CTR2(vlapic, "vlapic write offset %#lx, data %#lx",
1468 	    offset, data);
1469 
1470 	if (offset > sizeof(*lapic))
1471 		return (0);
1472 
1473 	/* Ignore MMIO accesses in x2APIC mode */
1474 	if (x2apic(vlapic) && mmio_access) {
1475 		VLAPIC_CTR2(vlapic, "MMIO write of %#lx to offset %#lx "
1476 		    "in x2APIC mode", data, offset);
1477 		return (0);
1478 	}
1479 
1480 	/*
1481 	 * XXX Generate GP fault for MSR accesses in xAPIC mode
1482 	 */
1483 	if (!x2apic(vlapic) && !mmio_access) {
1484 		VLAPIC_CTR2(vlapic, "x2APIC MSR write of %#lx to offset %#lx "
1485 		    "in xAPIC mode", data, offset);
1486 		return (0);
1487 	}
1488 
1489 	retval = 0;
1490 	switch(offset)
1491 	{
1492 		case APIC_OFFSET_ID:
1493 			lapic->id = data;
1494 			vlapic_id_write_handler(vlapic);
1495 			break;
1496 		case APIC_OFFSET_TPR:
1497 			vlapic_set_tpr(vlapic, data & 0xff);
1498 			break;
1499 		case APIC_OFFSET_EOI:
1500 			vlapic_process_eoi(vlapic);
1501 			break;
1502 		case APIC_OFFSET_LDR:
1503 			lapic->ldr = data;
1504 			vlapic_ldr_write_handler(vlapic);
1505 			break;
1506 		case APIC_OFFSET_DFR:
1507 			lapic->dfr = data;
1508 			vlapic_dfr_write_handler(vlapic);
1509 			break;
1510 		case APIC_OFFSET_SVR:
1511 			lapic->svr = data;
1512 			vlapic_svr_write_handler(vlapic);
1513 			break;
1514 		case APIC_OFFSET_ICR_LOW:
1515 			lapic->icr_lo = data;
1516 			if (x2apic(vlapic))
1517 				lapic->icr_hi = data >> 32;
1518 			retval = vlapic_icrlo_write_handler(vlapic, retu);
1519 			break;
1520 		case APIC_OFFSET_ICR_HI:
1521 			lapic->icr_hi = data;
1522 			break;
1523 		case APIC_OFFSET_CMCI_LVT:
1524 		case APIC_OFFSET_TIMER_LVT ... APIC_OFFSET_ERROR_LVT:
1525 			regptr = vlapic_get_lvtptr(vlapic, offset);
1526 			*regptr = data;
1527 			vlapic_lvt_write_handler(vlapic, offset);
1528 			break;
1529 		case APIC_OFFSET_TIMER_ICR:
1530 			lapic->icr_timer = data;
1531 			vlapic_icrtmr_write_handler(vlapic);
1532 			break;
1533 
1534 		case APIC_OFFSET_TIMER_DCR:
1535 			lapic->dcr_timer = data;
1536 			vlapic_dcr_write_handler(vlapic);
1537 			break;
1538 
1539 		case APIC_OFFSET_ESR:
1540 			vlapic_esr_write_handler(vlapic);
1541 			break;
1542 
1543 		case APIC_OFFSET_SELF_IPI:
1544 			if (x2apic(vlapic))
1545 				vlapic_self_ipi_handler(vlapic, data);
1546 			break;
1547 
1548 		case APIC_OFFSET_VER:
1549 		case APIC_OFFSET_APR:
1550 		case APIC_OFFSET_PPR:
1551 		case APIC_OFFSET_RRR:
1552 		case APIC_OFFSET_ISR0 ... APIC_OFFSET_ISR7:
1553 		case APIC_OFFSET_TMR0 ... APIC_OFFSET_TMR7:
1554 		case APIC_OFFSET_IRR0 ... APIC_OFFSET_IRR7:
1555 		case APIC_OFFSET_TIMER_CCR:
1556 		default:
1557 			// Read only.
1558 			break;
1559 	}
1560 
1561 	return (retval);
1562 }
1563 
1564 static void
1565 vlapic_reset(struct vlapic *vlapic)
1566 {
1567 	struct LAPIC *lapic;
1568 
1569 	lapic = vlapic->apic_page;
1570 	bzero(lapic, sizeof(struct LAPIC));
1571 
1572 	lapic->id = vlapic_get_id(vlapic);
1573 	lapic->version = VLAPIC_VERSION;
1574 	lapic->version |= (VLAPIC_MAXLVT_INDEX << MAXLVTSHIFT);
1575 	lapic->dfr = 0xffffffff;
1576 	lapic->svr = APIC_SVR_VECTOR;
1577 	vlapic_mask_lvts(vlapic);
1578 	vlapic_reset_tmr(vlapic);
1579 
1580 	lapic->dcr_timer = 0;
1581 	vlapic_dcr_write_handler(vlapic);
1582 
1583 	vlapic->svr_last = lapic->svr;
1584 }
1585 
1586 void
1587 vlapic_init(struct vlapic *vlapic)
1588 {
1589 	KASSERT(vlapic->vm != NULL, ("vlapic_init: vm is not initialized"));
1590 	KASSERT(vlapic->vcpuid >= 0 &&
1591 	    vlapic->vcpuid < vm_get_maxcpus(vlapic->vm),
1592 	    ("vlapic_init: vcpuid is not initialized"));
1593 	KASSERT(vlapic->apic_page != NULL, ("vlapic_init: apic_page is not "
1594 	    "initialized"));
1595 
1596 	/*
1597 	 * If the vlapic is configured in x2apic mode then it will be
1598 	 * accessed in the critical section via the MSR emulation code.
1599 	 *
1600 	 * Therefore the timer mutex must be a spinlock because blockable
1601 	 * mutexes cannot be acquired in a critical section.
1602 	 */
1603 	mtx_init(&vlapic->timer_mtx, "vlapic timer mtx", NULL, MTX_SPIN);
1604 	callout_init(&vlapic->callout, 1);
1605 
1606 	vlapic->msr_apicbase = DEFAULT_APIC_BASE | APICBASE_ENABLED;
1607 
1608 	if (vlapic->vcpuid == 0)
1609 		vlapic->msr_apicbase |= APICBASE_BSP;
1610 
1611 	vlapic->ipi_exit = false;
1612 
1613 	vlapic_reset(vlapic);
1614 }
1615 
1616 void
1617 vlapic_cleanup(struct vlapic *vlapic)
1618 {
1619 
1620 	callout_drain(&vlapic->callout);
1621 	mtx_destroy(&vlapic->timer_mtx);
1622 }
1623 
1624 uint64_t
1625 vlapic_get_apicbase(struct vlapic *vlapic)
1626 {
1627 
1628 	return (vlapic->msr_apicbase);
1629 }
1630 
1631 int
1632 vlapic_set_apicbase(struct vlapic *vlapic, uint64_t new)
1633 {
1634 
1635 	if (vlapic->msr_apicbase != new) {
1636 		VLAPIC_CTR2(vlapic, "Changing APIC_BASE MSR from %#lx to %#lx "
1637 		    "not supported", vlapic->msr_apicbase, new);
1638 		return (-1);
1639 	}
1640 
1641 	return (0);
1642 }
1643 
1644 void
1645 vlapic_set_x2apic_state(struct vcpu *vcpu, enum x2apic_state state)
1646 {
1647 	struct vlapic *vlapic;
1648 	struct LAPIC *lapic;
1649 
1650 	vlapic = vm_lapic(vcpu);
1651 
1652 	if (state == X2APIC_DISABLED)
1653 		vlapic->msr_apicbase &= ~APICBASE_X2APIC;
1654 	else
1655 		vlapic->msr_apicbase |= APICBASE_X2APIC;
1656 
1657 	/*
1658 	 * Reset the local APIC registers whose values are mode-dependent.
1659 	 *
1660 	 * XXX this works because the APIC mode can be changed only at vcpu
1661 	 * initialization time.
1662 	 */
1663 	lapic = vlapic->apic_page;
1664 	lapic->id = vlapic_get_id(vlapic);
1665 	if (x2apic(vlapic)) {
1666 		lapic->ldr = x2apic_ldr(vlapic);
1667 		lapic->dfr = 0;
1668 	} else {
1669 		lapic->ldr = 0;
1670 		lapic->dfr = 0xffffffff;
1671 	}
1672 
1673 	if (state == X2APIC_ENABLED) {
1674 		if (vlapic->ops.enable_x2apic_mode)
1675 			(*vlapic->ops.enable_x2apic_mode)(vlapic);
1676 	}
1677 }
1678 
1679 void
1680 vlapic_deliver_intr(struct vm *vm, bool level, uint32_t dest, bool phys,
1681     int delmode, int vec)
1682 {
1683 	struct vcpu *vcpu;
1684 	bool lowprio;
1685 	int vcpuid;
1686 	cpuset_t dmask;
1687 
1688 	if (delmode != IOART_DELFIXED &&
1689 	    delmode != IOART_DELLOPRI &&
1690 	    delmode != IOART_DELEXINT) {
1691 		VM_CTR1(vm, "vlapic intr invalid delmode %#x", delmode);
1692 		return;
1693 	}
1694 	lowprio = (delmode == IOART_DELLOPRI);
1695 
1696 	/*
1697 	 * We don't provide any virtual interrupt redirection hardware so
1698 	 * all interrupts originating from the ioapic or MSI specify the
1699 	 * 'dest' in the legacy xAPIC format.
1700 	 */
1701 	vlapic_calcdest(vm, &dmask, dest, phys, lowprio, false);
1702 
1703 	CPU_FOREACH_ISSET(vcpuid, &dmask) {
1704 		vcpu = vm_vcpu(vm, vcpuid);
1705 		if (delmode == IOART_DELEXINT) {
1706 			vm_inject_extint(vcpu);
1707 		} else {
1708 			lapic_set_intr(vcpu, vec, level);
1709 		}
1710 	}
1711 }
1712 
1713 void
1714 vlapic_post_intr(struct vlapic *vlapic, int hostcpu, int ipinum)
1715 {
1716 	/*
1717 	 * Post an interrupt to the vcpu currently running on 'hostcpu'.
1718 	 *
1719 	 * This is done by leveraging features like Posted Interrupts (Intel)
1720 	 * Doorbell MSR (AMD AVIC) that avoid a VM exit.
1721 	 *
1722 	 * If neither of these features are available then fallback to
1723 	 * sending an IPI to 'hostcpu'.
1724 	 */
1725 	if (vlapic->ops.post_intr)
1726 		(*vlapic->ops.post_intr)(vlapic, hostcpu);
1727 	else
1728 		ipi_cpu(hostcpu, ipinum);
1729 }
1730 
1731 bool
1732 vlapic_enabled(struct vlapic *vlapic)
1733 {
1734 	struct LAPIC *lapic = vlapic->apic_page;
1735 
1736 	if ((vlapic->msr_apicbase & APICBASE_ENABLED) != 0 &&
1737 	    (lapic->svr & APIC_SVR_ENABLE) != 0)
1738 		return (true);
1739 	else
1740 		return (false);
1741 }
1742 
1743 static void
1744 vlapic_set_tmr(struct vlapic *vlapic, int vector, bool level)
1745 {
1746 	struct LAPIC *lapic;
1747 	uint32_t *tmrptr, mask;
1748 	int idx;
1749 
1750 	lapic = vlapic->apic_page;
1751 	tmrptr = &lapic->tmr0;
1752 	idx = (vector / 32) * 4;
1753 	mask = 1 << (vector % 32);
1754 	if (level)
1755 		tmrptr[idx] |= mask;
1756 	else
1757 		tmrptr[idx] &= ~mask;
1758 
1759 	if (vlapic->ops.set_tmr != NULL)
1760 		(*vlapic->ops.set_tmr)(vlapic, vector, level);
1761 }
1762 
1763 void
1764 vlapic_reset_tmr(struct vlapic *vlapic)
1765 {
1766 	int vector;
1767 
1768 	VLAPIC_CTR0(vlapic, "vlapic resetting all vectors to edge-triggered");
1769 
1770 	for (vector = 0; vector <= 255; vector++)
1771 		vlapic_set_tmr(vlapic, vector, false);
1772 }
1773 
1774 void
1775 vlapic_set_tmr_level(struct vlapic *vlapic, uint32_t dest, bool phys,
1776     int delmode, int vector)
1777 {
1778 	cpuset_t dmask;
1779 	bool lowprio;
1780 
1781 	KASSERT(vector >= 0 && vector <= 255, ("invalid vector %d", vector));
1782 
1783 	/*
1784 	 * A level trigger is valid only for fixed and lowprio delivery modes.
1785 	 */
1786 	if (delmode != APIC_DELMODE_FIXED && delmode != APIC_DELMODE_LOWPRIO) {
1787 		VLAPIC_CTR1(vlapic, "Ignoring level trigger-mode for "
1788 		    "delivery-mode %d", delmode);
1789 		return;
1790 	}
1791 
1792 	lowprio = (delmode == APIC_DELMODE_LOWPRIO);
1793 	vlapic_calcdest(vlapic->vm, &dmask, dest, phys, lowprio, false);
1794 
1795 	if (!CPU_ISSET(vlapic->vcpuid, &dmask))
1796 		return;
1797 
1798 	VLAPIC_CTR1(vlapic, "vector %d set to level-triggered", vector);
1799 	vlapic_set_tmr(vlapic, vector, true);
1800 }
1801 
1802 #ifdef BHYVE_SNAPSHOT
1803 static void
1804 vlapic_reset_callout(struct vlapic *vlapic, uint32_t ccr)
1805 {
1806 	/* The implementation is similar to the one in the
1807 	 * `vlapic_icrtmr_write_handler` function
1808 	 */
1809 	sbintime_t sbt;
1810 	struct bintime bt;
1811 
1812 	VLAPIC_TIMER_LOCK(vlapic);
1813 
1814 	bt = vlapic->timer_freq_bt;
1815 	bintime_mul(&bt, ccr);
1816 
1817 	if (ccr != 0) {
1818 		binuptime(&vlapic->timer_fire_bt);
1819 		bintime_add(&vlapic->timer_fire_bt, &bt);
1820 
1821 		sbt = bttosbt(bt);
1822 		vlapic_callout_reset(vlapic, sbt);
1823 	} else {
1824 		/* even if the CCR was 0, periodic timers should be reset */
1825 		if (vlapic_periodic_timer(vlapic)) {
1826 			binuptime(&vlapic->timer_fire_bt);
1827 			bintime_add(&vlapic->timer_fire_bt,
1828 				    &vlapic->timer_period_bt);
1829 			sbt = bttosbt(vlapic->timer_period_bt);
1830 
1831 			callout_stop(&vlapic->callout);
1832 			vlapic_callout_reset(vlapic, sbt);
1833 		}
1834 	}
1835 
1836 	VLAPIC_TIMER_UNLOCK(vlapic);
1837 }
1838 
1839 int
1840 vlapic_snapshot(struct vm *vm, struct vm_snapshot_meta *meta)
1841 {
1842 	int ret;
1843 	struct vcpu *vcpu;
1844 	struct vlapic *vlapic;
1845 	struct LAPIC *lapic;
1846 	uint32_t ccr;
1847 	uint16_t i, maxcpus;
1848 
1849 	KASSERT(vm != NULL, ("%s: arg was NULL", __func__));
1850 
1851 	ret = 0;
1852 
1853 	maxcpus = vm_get_maxcpus(vm);
1854 	for (i = 0; i < maxcpus; i++) {
1855 		vcpu = vm_vcpu(vm, i);
1856 		if (vcpu == NULL)
1857 			continue;
1858 		vlapic = vm_lapic(vcpu);
1859 
1860 		/* snapshot the page first; timer period depends on icr_timer */
1861 		lapic = vlapic->apic_page;
1862 		SNAPSHOT_BUF_OR_LEAVE(lapic, PAGE_SIZE, meta, ret, done);
1863 
1864 		SNAPSHOT_VAR_OR_LEAVE(vlapic->esr_pending, meta, ret, done);
1865 
1866 		SNAPSHOT_VAR_OR_LEAVE(vlapic->timer_freq_bt.sec,
1867 				      meta, ret, done);
1868 		SNAPSHOT_VAR_OR_LEAVE(vlapic->timer_freq_bt.frac,
1869 				      meta, ret, done);
1870 
1871 		/*
1872 		 * Timer period is equal to 'icr_timer' ticks at a frequency of
1873 		 * 'timer_freq_bt'.
1874 		 */
1875 		if (meta->op == VM_SNAPSHOT_RESTORE) {
1876 			vlapic->timer_period_bt = vlapic->timer_freq_bt;
1877 			bintime_mul(&vlapic->timer_period_bt, lapic->icr_timer);
1878 		}
1879 
1880 		SNAPSHOT_BUF_OR_LEAVE(vlapic->isrvec_stk,
1881 				      sizeof(vlapic->isrvec_stk),
1882 				      meta, ret, done);
1883 		SNAPSHOT_VAR_OR_LEAVE(vlapic->isrvec_stk_top, meta, ret, done);
1884 
1885 		SNAPSHOT_BUF_OR_LEAVE(vlapic->lvt_last,
1886 				      sizeof(vlapic->lvt_last),
1887 				      meta, ret, done);
1888 
1889 		if (meta->op == VM_SNAPSHOT_SAVE)
1890 			ccr = vlapic_get_ccr(vlapic);
1891 
1892 		SNAPSHOT_VAR_OR_LEAVE(ccr, meta, ret, done);
1893 
1894 		if (meta->op == VM_SNAPSHOT_RESTORE &&
1895 		    vlapic_enabled(vlapic) && lapic->icr_timer != 0) {
1896 			/* Reset the value of the 'timer_fire_bt' and the vlapic
1897 			 * callout based on the value of the current count
1898 			 * register saved when the VM snapshot was created.
1899 			 * If initial count register is 0, timer is not used.
1900 			 * Look at "10.5.4 APIC Timer" in Software Developer Manual.
1901 			 */
1902 			vlapic_reset_callout(vlapic, ccr);
1903 		}
1904 	}
1905 
1906 done:
1907 	return (ret);
1908 }
1909 #endif
1910