xref: /freebsd-11-stable/sys/amd64/vmm/io/vlapic.c (revision 07cfaa37f8849d40a14a122448064fbc5597aaa0)
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
vlapic_get_id(struct vlapic * vlapic)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
x2apic_ldr(struct vlapic * vlapic)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
vlapic_dfr_write_handler(struct vlapic * vlapic)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
vlapic_ldr_write_handler(struct vlapic * vlapic)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
vlapic_id_write_handler(struct vlapic * vlapic)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
vlapic_timer_divisor(uint32_t dcr)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
vlapic_get_ccr(struct vlapic * vlapic)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
vlapic_dcr_write_handler(struct vlapic * vlapic)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
vlapic_esr_write_handler(struct vlapic * vlapic)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
vlapic_set_intr_ready(struct vlapic * vlapic,int vector,bool level)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 *
vlapic_get_lvtptr(struct vlapic * vlapic,uint32_t offset)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
lvt_off_to_idx(uint32_t offset)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
vlapic_get_lvt(struct vlapic * vlapic,uint32_t offset)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
vlapic_lvt_write_handler(struct vlapic * vlapic,uint32_t offset)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
vlapic_mask_lvts(struct vlapic * vlapic)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
vlapic_fire_lvt(struct vlapic * vlapic,uint32_t lvt)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
dump_isrvec_stk(struct vlapic * vlapic)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
vlapic_update_ppr(struct vlapic * vlapic)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 void
vlapic_sync_tpr(struct vlapic * vlapic)551 vlapic_sync_tpr(struct vlapic *vlapic)
552 {
553 	vlapic_update_ppr(vlapic);
554 }
555 
556 static VMM_STAT(VLAPIC_GRATUITOUS_EOI, "EOI without any in-service interrupt");
557 
558 static void
vlapic_process_eoi(struct vlapic * vlapic)559 vlapic_process_eoi(struct vlapic *vlapic)
560 {
561 	struct LAPIC	*lapic = vlapic->apic_page;
562 	uint32_t	*isrptr, *tmrptr;
563 	int		i, idx, bitpos, vector;
564 
565 	isrptr = &lapic->isr0;
566 	tmrptr = &lapic->tmr0;
567 
568 	for (i = 7; i >= 0; i--) {
569 		idx = i * 4;
570 		bitpos = fls(isrptr[idx]);
571 		if (bitpos-- != 0) {
572 			if (vlapic->isrvec_stk_top <= 0) {
573 				panic("invalid vlapic isrvec_stk_top %d",
574 				      vlapic->isrvec_stk_top);
575 			}
576 			isrptr[idx] &= ~(1 << bitpos);
577 			vector = i * 32 + bitpos;
578 			VCPU_CTR1(vlapic->vm, vlapic->vcpuid, "EOI vector %d",
579 			    vector);
580 			VLAPIC_CTR_ISR(vlapic, "vlapic_process_eoi");
581 			vlapic->isrvec_stk_top--;
582 			vlapic_update_ppr(vlapic);
583 			if ((tmrptr[idx] & (1 << bitpos)) != 0) {
584 				vioapic_process_eoi(vlapic->vm, vlapic->vcpuid,
585 				    vector);
586 			}
587 			return;
588 		}
589 	}
590 	VCPU_CTR0(vlapic->vm, vlapic->vcpuid, "Gratuitous EOI");
591 	vmm_stat_incr(vlapic->vm, vlapic->vcpuid, VLAPIC_GRATUITOUS_EOI, 1);
592 }
593 
594 static __inline int
vlapic_get_lvt_field(uint32_t lvt,uint32_t mask)595 vlapic_get_lvt_field(uint32_t lvt, uint32_t mask)
596 {
597 
598 	return (lvt & mask);
599 }
600 
601 static __inline int
vlapic_periodic_timer(struct vlapic * vlapic)602 vlapic_periodic_timer(struct vlapic *vlapic)
603 {
604 	uint32_t lvt;
605 
606 	lvt = vlapic_get_lvt(vlapic, APIC_OFFSET_TIMER_LVT);
607 
608 	return (vlapic_get_lvt_field(lvt, APIC_LVTT_TM_PERIODIC));
609 }
610 
611 static VMM_STAT(VLAPIC_INTR_ERROR, "error interrupts generated by vlapic");
612 
613 void
vlapic_set_error(struct vlapic * vlapic,uint32_t mask)614 vlapic_set_error(struct vlapic *vlapic, uint32_t mask)
615 {
616 	uint32_t lvt;
617 
618 	vlapic->esr_pending |= mask;
619 	if (vlapic->esr_firing)
620 		return;
621 	vlapic->esr_firing = 1;
622 
623 	// The error LVT always uses the fixed delivery mode.
624 	lvt = vlapic_get_lvt(vlapic, APIC_OFFSET_ERROR_LVT);
625 	if (vlapic_fire_lvt(vlapic, lvt | APIC_LVT_DM_FIXED)) {
626 		vmm_stat_incr(vlapic->vm, vlapic->vcpuid, VLAPIC_INTR_ERROR, 1);
627 	}
628 	vlapic->esr_firing = 0;
629 }
630 
631 static VMM_STAT(VLAPIC_INTR_TIMER, "timer interrupts generated by vlapic");
632 
633 static void
vlapic_fire_timer(struct vlapic * vlapic)634 vlapic_fire_timer(struct vlapic *vlapic)
635 {
636 	uint32_t lvt;
637 
638 	KASSERT(VLAPIC_TIMER_LOCKED(vlapic), ("vlapic_fire_timer not locked"));
639 
640 	// The timer LVT always uses the fixed delivery mode.
641 	lvt = vlapic_get_lvt(vlapic, APIC_OFFSET_TIMER_LVT);
642 	if (vlapic_fire_lvt(vlapic, lvt | APIC_LVT_DM_FIXED)) {
643 		VLAPIC_CTR0(vlapic, "vlapic timer fired");
644 		vmm_stat_incr(vlapic->vm, vlapic->vcpuid, VLAPIC_INTR_TIMER, 1);
645 	}
646 }
647 
648 static VMM_STAT(VLAPIC_INTR_CMC,
649     "corrected machine check interrupts generated by vlapic");
650 
651 void
vlapic_fire_cmci(struct vlapic * vlapic)652 vlapic_fire_cmci(struct vlapic *vlapic)
653 {
654 	uint32_t lvt;
655 
656 	lvt = vlapic_get_lvt(vlapic, APIC_OFFSET_CMCI_LVT);
657 	if (vlapic_fire_lvt(vlapic, lvt)) {
658 		vmm_stat_incr(vlapic->vm, vlapic->vcpuid, VLAPIC_INTR_CMC, 1);
659 	}
660 }
661 
662 static VMM_STAT_ARRAY(LVTS_TRIGGERRED, VLAPIC_MAXLVT_INDEX + 1,
663     "lvts triggered");
664 
665 int
vlapic_trigger_lvt(struct vlapic * vlapic,int vector)666 vlapic_trigger_lvt(struct vlapic *vlapic, int vector)
667 {
668 	uint32_t lvt;
669 
670 	if (vlapic_enabled(vlapic) == false) {
671 		/*
672 		 * When the local APIC is global/hardware disabled,
673 		 * LINT[1:0] pins are configured as INTR and NMI pins,
674 		 * respectively.
675 		*/
676 		switch (vector) {
677 			case APIC_LVT_LINT0:
678 				vm_inject_extint(vlapic->vm, vlapic->vcpuid);
679 				break;
680 			case APIC_LVT_LINT1:
681 				vm_inject_nmi(vlapic->vm, vlapic->vcpuid);
682 				break;
683 			default:
684 				break;
685 		}
686 		return (0);
687 	}
688 
689 	switch (vector) {
690 	case APIC_LVT_LINT0:
691 		lvt = vlapic_get_lvt(vlapic, APIC_OFFSET_LINT0_LVT);
692 		break;
693 	case APIC_LVT_LINT1:
694 		lvt = vlapic_get_lvt(vlapic, APIC_OFFSET_LINT1_LVT);
695 		break;
696 	case APIC_LVT_TIMER:
697 		lvt = vlapic_get_lvt(vlapic, APIC_OFFSET_TIMER_LVT);
698 		lvt |= APIC_LVT_DM_FIXED;
699 		break;
700 	case APIC_LVT_ERROR:
701 		lvt = vlapic_get_lvt(vlapic, APIC_OFFSET_ERROR_LVT);
702 		lvt |= APIC_LVT_DM_FIXED;
703 		break;
704 	case APIC_LVT_PMC:
705 		lvt = vlapic_get_lvt(vlapic, APIC_OFFSET_PERF_LVT);
706 		break;
707 	case APIC_LVT_THERMAL:
708 		lvt = vlapic_get_lvt(vlapic, APIC_OFFSET_THERM_LVT);
709 		break;
710 	case APIC_LVT_CMCI:
711 		lvt = vlapic_get_lvt(vlapic, APIC_OFFSET_CMCI_LVT);
712 		break;
713 	default:
714 		return (EINVAL);
715 	}
716 	if (vlapic_fire_lvt(vlapic, lvt)) {
717 		vmm_stat_array_incr(vlapic->vm, vlapic->vcpuid,
718 		    LVTS_TRIGGERRED, vector, 1);
719 	}
720 	return (0);
721 }
722 
723 static void
vlapic_callout_handler(void * arg)724 vlapic_callout_handler(void *arg)
725 {
726 	struct vlapic *vlapic;
727 	struct bintime bt, btnow;
728 	sbintime_t rem_sbt;
729 
730 	vlapic = arg;
731 
732 	VLAPIC_TIMER_LOCK(vlapic);
733 	if (callout_pending(&vlapic->callout))	/* callout was reset */
734 		goto done;
735 
736 	if (!callout_active(&vlapic->callout))	/* callout was stopped */
737 		goto done;
738 
739 	callout_deactivate(&vlapic->callout);
740 
741 	vlapic_fire_timer(vlapic);
742 
743 	if (vlapic_periodic_timer(vlapic)) {
744 		binuptime(&btnow);
745 		KASSERT(bintime_cmp(&btnow, &vlapic->timer_fire_bt, >=),
746 		    ("vlapic callout at %#lx.%#lx, expected at %#lx.#%lx",
747 		    btnow.sec, btnow.frac, vlapic->timer_fire_bt.sec,
748 		    vlapic->timer_fire_bt.frac));
749 
750 		/*
751 		 * Compute the delta between when the timer was supposed to
752 		 * fire and the present time.
753 		 */
754 		bt = btnow;
755 		bintime_sub(&bt, &vlapic->timer_fire_bt);
756 
757 		rem_sbt = bttosbt(vlapic->timer_period_bt);
758 		if (bintime_cmp(&bt, &vlapic->timer_period_bt, <)) {
759 			/*
760 			 * Adjust the time until the next countdown downward
761 			 * to account for the lost time.
762 			 */
763 			rem_sbt -= bttosbt(bt);
764 		} else {
765 			/*
766 			 * If the delta is greater than the timer period then
767 			 * just reset our time base instead of trying to catch
768 			 * up.
769 			 */
770 			vlapic->timer_fire_bt = btnow;
771 			VLAPIC_CTR2(vlapic, "vlapic timer lagging by %lu "
772 			    "usecs, period is %lu usecs - resetting time base",
773 			    bttosbt(bt) / SBT_1US,
774 			    bttosbt(vlapic->timer_period_bt) / SBT_1US);
775 		}
776 
777 		bintime_add(&vlapic->timer_fire_bt, &vlapic->timer_period_bt);
778 		callout_reset_sbt(&vlapic->callout, rem_sbt, 0,
779 		    vlapic_callout_handler, vlapic, 0);
780 	}
781 done:
782 	VLAPIC_TIMER_UNLOCK(vlapic);
783 }
784 
785 void
vlapic_icrtmr_write_handler(struct vlapic * vlapic)786 vlapic_icrtmr_write_handler(struct vlapic *vlapic)
787 {
788 	struct LAPIC *lapic;
789 	sbintime_t sbt;
790 	uint32_t icr_timer;
791 
792 	VLAPIC_TIMER_LOCK(vlapic);
793 
794 	lapic = vlapic->apic_page;
795 	icr_timer = lapic->icr_timer;
796 
797 	vlapic->timer_period_bt = vlapic->timer_freq_bt;
798 	bintime_mul(&vlapic->timer_period_bt, icr_timer);
799 
800 	if (icr_timer != 0) {
801 		binuptime(&vlapic->timer_fire_bt);
802 		bintime_add(&vlapic->timer_fire_bt, &vlapic->timer_period_bt);
803 
804 		sbt = bttosbt(vlapic->timer_period_bt);
805 		callout_reset_sbt(&vlapic->callout, sbt, 0,
806 		    vlapic_callout_handler, vlapic, 0);
807 	} else
808 		callout_stop(&vlapic->callout);
809 
810 	VLAPIC_TIMER_UNLOCK(vlapic);
811 }
812 
813 /*
814  * This function populates 'dmask' with the set of vcpus that match the
815  * addressing specified by the (dest, phys, lowprio) tuple.
816  *
817  * 'x2apic_dest' specifies whether 'dest' is interpreted as x2APIC (32-bit)
818  * or xAPIC (8-bit) destination field.
819  */
820 static void
vlapic_calcdest(struct vm * vm,cpuset_t * dmask,uint32_t dest,bool phys,bool lowprio,bool x2apic_dest)821 vlapic_calcdest(struct vm *vm, cpuset_t *dmask, uint32_t dest, bool phys,
822     bool lowprio, bool x2apic_dest)
823 {
824 	struct vlapic *vlapic;
825 	uint32_t dfr, ldr, ldest, cluster;
826 	uint32_t mda_flat_ldest, mda_cluster_ldest, mda_ldest, mda_cluster_id;
827 	cpuset_t amask;
828 	int vcpuid;
829 
830 	if ((x2apic_dest && dest == 0xffffffff) ||
831 	    (!x2apic_dest && dest == 0xff)) {
832 		/*
833 		 * Broadcast in both logical and physical modes.
834 		 */
835 		*dmask = vm_active_cpus(vm);
836 		return;
837 	}
838 
839 	if (phys) {
840 		/*
841 		 * Physical mode: destination is APIC ID.
842 		 */
843 		CPU_ZERO(dmask);
844 		vcpuid = vm_apicid2vcpuid(vm, dest);
845 		amask = vm_active_cpus(vm);
846 		if (vcpuid < vm_get_maxcpus(vm) && CPU_ISSET(vcpuid, &amask))
847 			CPU_SET(vcpuid, dmask);
848 	} else {
849 		/*
850 		 * In the "Flat Model" the MDA is interpreted as an 8-bit wide
851 		 * bitmask. This model is only available in the xAPIC mode.
852 		 */
853 		mda_flat_ldest = dest & 0xff;
854 
855 		/*
856 		 * In the "Cluster Model" the MDA is used to identify a
857 		 * specific cluster and a set of APICs in that cluster.
858 		 */
859 		if (x2apic_dest) {
860 			mda_cluster_id = dest >> 16;
861 			mda_cluster_ldest = dest & 0xffff;
862 		} else {
863 			mda_cluster_id = (dest >> 4) & 0xf;
864 			mda_cluster_ldest = dest & 0xf;
865 		}
866 
867 		/*
868 		 * Logical mode: match each APIC that has a bit set
869 		 * in it's LDR that matches a bit in the ldest.
870 		 */
871 		CPU_ZERO(dmask);
872 		amask = vm_active_cpus(vm);
873 		while ((vcpuid = CPU_FFS(&amask)) != 0) {
874 			vcpuid--;
875 			CPU_CLR(vcpuid, &amask);
876 
877 			vlapic = vm_lapic(vm, vcpuid);
878 			dfr = vlapic->apic_page->dfr;
879 			ldr = vlapic->apic_page->ldr;
880 
881 			if ((dfr & APIC_DFR_MODEL_MASK) ==
882 			    APIC_DFR_MODEL_FLAT) {
883 				ldest = ldr >> 24;
884 				mda_ldest = mda_flat_ldest;
885 			} else if ((dfr & APIC_DFR_MODEL_MASK) ==
886 			    APIC_DFR_MODEL_CLUSTER) {
887 				if (x2apic(vlapic)) {
888 					cluster = ldr >> 16;
889 					ldest = ldr & 0xffff;
890 				} else {
891 					cluster = ldr >> 28;
892 					ldest = (ldr >> 24) & 0xf;
893 				}
894 				if (cluster != mda_cluster_id)
895 					continue;
896 				mda_ldest = mda_cluster_ldest;
897 			} else {
898 				/*
899 				 * Guest has configured a bad logical
900 				 * model for this vcpu - skip it.
901 				 */
902 				VLAPIC_CTR1(vlapic, "vlapic has bad logical "
903 				    "model %x - cannot deliver interrupt", dfr);
904 				continue;
905 			}
906 
907 			if ((mda_ldest & ldest) != 0) {
908 				CPU_SET(vcpuid, dmask);
909 				if (lowprio)
910 					break;
911 			}
912 		}
913 	}
914 }
915 
916 static VMM_STAT_ARRAY(IPIS_SENT, VM_MAXCPU, "ipis sent to vcpu");
917 
918 static void
vlapic_set_tpr(struct vlapic * vlapic,uint8_t val)919 vlapic_set_tpr(struct vlapic *vlapic, uint8_t val)
920 {
921 	struct LAPIC *lapic = vlapic->apic_page;
922 
923 	if (lapic->tpr != val) {
924 		VCPU_CTR2(vlapic->vm, vlapic->vcpuid, "vlapic TPR changed "
925 		    "from %#x to %#x", lapic->tpr, val);
926 		lapic->tpr = val;
927 		vlapic_update_ppr(vlapic);
928 	}
929 }
930 
931 static uint8_t
vlapic_get_tpr(struct vlapic * vlapic)932 vlapic_get_tpr(struct vlapic *vlapic)
933 {
934 	struct LAPIC *lapic = vlapic->apic_page;
935 
936 	return (lapic->tpr);
937 }
938 
939 void
vlapic_set_cr8(struct vlapic * vlapic,uint64_t val)940 vlapic_set_cr8(struct vlapic *vlapic, uint64_t val)
941 {
942 	uint8_t tpr;
943 
944 	if (val & ~0xf) {
945 		vm_inject_gp(vlapic->vm, vlapic->vcpuid);
946 		return;
947 	}
948 
949 	tpr = val << 4;
950 	vlapic_set_tpr(vlapic, tpr);
951 }
952 
953 uint64_t
vlapic_get_cr8(struct vlapic * vlapic)954 vlapic_get_cr8(struct vlapic *vlapic)
955 {
956 	uint8_t tpr;
957 
958 	tpr = vlapic_get_tpr(vlapic);
959 	return (tpr >> 4);
960 }
961 
962 int
vlapic_icrlo_write_handler(struct vlapic * vlapic,bool * retu)963 vlapic_icrlo_write_handler(struct vlapic *vlapic, bool *retu)
964 {
965 	int i;
966 	bool phys;
967 	cpuset_t dmask;
968 	uint64_t icrval;
969 	uint32_t dest, vec, mode;
970 	struct vlapic *vlapic2;
971 	struct vm_exit *vmexit;
972 	struct LAPIC *lapic;
973 	uint16_t maxcpus;
974 
975 	lapic = vlapic->apic_page;
976 	lapic->icr_lo &= ~APIC_DELSTAT_PEND;
977 	icrval = ((uint64_t)lapic->icr_hi << 32) | lapic->icr_lo;
978 
979 	if (x2apic(vlapic))
980 		dest = icrval >> 32;
981 	else
982 		dest = icrval >> (32 + 24);
983 	vec = icrval & APIC_VECTOR_MASK;
984 	mode = icrval & APIC_DELMODE_MASK;
985 
986 	if (mode == APIC_DELMODE_FIXED && vec < 16) {
987 		vlapic_set_error(vlapic, APIC_ESR_SEND_ILLEGAL_VECTOR);
988 		VLAPIC_CTR1(vlapic, "Ignoring invalid IPI %d", vec);
989 		return (0);
990 	}
991 
992 	VLAPIC_CTR2(vlapic, "icrlo 0x%016lx triggered ipi %d", icrval, vec);
993 
994 	if (mode == APIC_DELMODE_FIXED || mode == APIC_DELMODE_NMI) {
995 		switch (icrval & APIC_DEST_MASK) {
996 		case APIC_DEST_DESTFLD:
997 			phys = ((icrval & APIC_DESTMODE_LOG) == 0);
998 			vlapic_calcdest(vlapic->vm, &dmask, dest, phys, false,
999 			    x2apic(vlapic));
1000 			break;
1001 		case APIC_DEST_SELF:
1002 			CPU_SETOF(vlapic->vcpuid, &dmask);
1003 			break;
1004 		case APIC_DEST_ALLISELF:
1005 			dmask = vm_active_cpus(vlapic->vm);
1006 			break;
1007 		case APIC_DEST_ALLESELF:
1008 			dmask = vm_active_cpus(vlapic->vm);
1009 			CPU_CLR(vlapic->vcpuid, &dmask);
1010 			break;
1011 		default:
1012 			CPU_ZERO(&dmask);	/* satisfy gcc */
1013 			break;
1014 		}
1015 
1016 		while ((i = CPU_FFS(&dmask)) != 0) {
1017 			i--;
1018 			CPU_CLR(i, &dmask);
1019 			if (mode == APIC_DELMODE_FIXED) {
1020 				lapic_intr_edge(vlapic->vm, i, vec);
1021 				vmm_stat_array_incr(vlapic->vm, vlapic->vcpuid,
1022 						    IPIS_SENT, i, 1);
1023 				VLAPIC_CTR2(vlapic, "vlapic sending ipi %d "
1024 				    "to vcpuid %d", vec, i);
1025 			} else {
1026 				vm_inject_nmi(vlapic->vm, i);
1027 				VLAPIC_CTR1(vlapic, "vlapic sending ipi nmi "
1028 				    "to vcpuid %d", i);
1029 			}
1030 		}
1031 
1032 		return (0);	/* handled completely in the kernel */
1033 	}
1034 
1035 	maxcpus = vm_get_maxcpus(vlapic->vm);
1036 	if (mode == APIC_DELMODE_INIT) {
1037 		if ((icrval & APIC_LEVEL_MASK) == APIC_LEVEL_DEASSERT)
1038 			return (0);
1039 
1040 		if (vlapic->vcpuid == 0 && dest != 0 && dest < maxcpus) {
1041 			vlapic2 = vm_lapic(vlapic->vm, dest);
1042 
1043 			/* move from INIT to waiting-for-SIPI state */
1044 			if (vlapic2->boot_state == BS_INIT) {
1045 				vlapic2->boot_state = BS_SIPI;
1046 			}
1047 
1048 			return (0);
1049 		}
1050 	}
1051 
1052 	if (mode == APIC_DELMODE_STARTUP) {
1053 		if (vlapic->vcpuid == 0 && dest != 0 && dest < maxcpus) {
1054 			vlapic2 = vm_lapic(vlapic->vm, dest);
1055 
1056 			/*
1057 			 * Ignore SIPIs in any state other than wait-for-SIPI
1058 			 */
1059 			if (vlapic2->boot_state != BS_SIPI)
1060 				return (0);
1061 
1062 			vlapic2->boot_state = BS_RUNNING;
1063 
1064 			*retu = true;
1065 			vmexit = vm_exitinfo(vlapic->vm, vlapic->vcpuid);
1066 			vmexit->exitcode = VM_EXITCODE_SPINUP_AP;
1067 			vmexit->u.spinup_ap.vcpu = dest;
1068 			vmexit->u.spinup_ap.rip = vec << PAGE_SHIFT;
1069 
1070 			return (0);
1071 		}
1072 	}
1073 
1074 	/*
1075 	 * This will cause a return to userland.
1076 	 */
1077 	return (1);
1078 }
1079 
1080 void
vlapic_self_ipi_handler(struct vlapic * vlapic,uint64_t val)1081 vlapic_self_ipi_handler(struct vlapic *vlapic, uint64_t val)
1082 {
1083 	int vec;
1084 
1085 	KASSERT(x2apic(vlapic), ("SELF_IPI does not exist in xAPIC mode"));
1086 
1087 	vec = val & 0xff;
1088 	lapic_intr_edge(vlapic->vm, vlapic->vcpuid, vec);
1089 	vmm_stat_array_incr(vlapic->vm, vlapic->vcpuid, IPIS_SENT,
1090 	    vlapic->vcpuid, 1);
1091 	VLAPIC_CTR1(vlapic, "vlapic self-ipi %d", vec);
1092 }
1093 
1094 int
vlapic_pending_intr(struct vlapic * vlapic,int * vecptr)1095 vlapic_pending_intr(struct vlapic *vlapic, int *vecptr)
1096 {
1097 	struct LAPIC	*lapic = vlapic->apic_page;
1098 	int	  	 idx, i, bitpos, vector;
1099 	uint32_t	*irrptr, val;
1100 
1101 	vlapic_update_ppr(vlapic);
1102 
1103 	if (vlapic->ops.pending_intr)
1104 		return ((*vlapic->ops.pending_intr)(vlapic, vecptr));
1105 
1106 	irrptr = &lapic->irr0;
1107 
1108 	for (i = 7; i >= 0; i--) {
1109 		idx = i * 4;
1110 		val = atomic_load_acq_int(&irrptr[idx]);
1111 		bitpos = fls(val);
1112 		if (bitpos != 0) {
1113 			vector = i * 32 + (bitpos - 1);
1114 			if (PRIO(vector) > PRIO(lapic->ppr)) {
1115 				VLAPIC_CTR1(vlapic, "pending intr %d", vector);
1116 				if (vecptr != NULL)
1117 					*vecptr = vector;
1118 				return (1);
1119 			} else
1120 				break;
1121 		}
1122 	}
1123 	return (0);
1124 }
1125 
1126 void
vlapic_intr_accepted(struct vlapic * vlapic,int vector)1127 vlapic_intr_accepted(struct vlapic *vlapic, int vector)
1128 {
1129 	struct LAPIC	*lapic = vlapic->apic_page;
1130 	uint32_t	*irrptr, *isrptr;
1131 	int		idx, stk_top;
1132 
1133 	if (vlapic->ops.intr_accepted)
1134 		return ((*vlapic->ops.intr_accepted)(vlapic, vector));
1135 
1136 	/*
1137 	 * clear the ready bit for vector being accepted in irr
1138 	 * and set the vector as in service in isr.
1139 	 */
1140 	idx = (vector / 32) * 4;
1141 
1142 	irrptr = &lapic->irr0;
1143 	atomic_clear_int(&irrptr[idx], 1 << (vector % 32));
1144 	VLAPIC_CTR_IRR(vlapic, "vlapic_intr_accepted");
1145 
1146 	isrptr = &lapic->isr0;
1147 	isrptr[idx] |= 1 << (vector % 32);
1148 	VLAPIC_CTR_ISR(vlapic, "vlapic_intr_accepted");
1149 
1150 	/*
1151 	 * Update the PPR
1152 	 */
1153 	vlapic->isrvec_stk_top++;
1154 
1155 	stk_top = vlapic->isrvec_stk_top;
1156 	if (stk_top >= ISRVEC_STK_SIZE)
1157 		panic("isrvec_stk_top overflow %d", stk_top);
1158 
1159 	vlapic->isrvec_stk[stk_top] = vector;
1160 }
1161 
1162 void
vlapic_svr_write_handler(struct vlapic * vlapic)1163 vlapic_svr_write_handler(struct vlapic *vlapic)
1164 {
1165 	struct LAPIC *lapic;
1166 	uint32_t old, new, changed;
1167 
1168 	lapic = vlapic->apic_page;
1169 
1170 	new = lapic->svr;
1171 	old = vlapic->svr_last;
1172 	vlapic->svr_last = new;
1173 
1174 	changed = old ^ new;
1175 	if ((changed & APIC_SVR_ENABLE) != 0) {
1176 		if ((new & APIC_SVR_ENABLE) == 0) {
1177 			/*
1178 			 * The apic is now disabled so stop the apic timer
1179 			 * and mask all the LVT entries.
1180 			 */
1181 			VLAPIC_CTR0(vlapic, "vlapic is software-disabled");
1182 			VLAPIC_TIMER_LOCK(vlapic);
1183 			callout_stop(&vlapic->callout);
1184 			VLAPIC_TIMER_UNLOCK(vlapic);
1185 			vlapic_mask_lvts(vlapic);
1186 		} else {
1187 			/*
1188 			 * The apic is now enabled so restart the apic timer
1189 			 * if it is configured in periodic mode.
1190 			 */
1191 			VLAPIC_CTR0(vlapic, "vlapic is software-enabled");
1192 			if (vlapic_periodic_timer(vlapic))
1193 				vlapic_icrtmr_write_handler(vlapic);
1194 		}
1195 	}
1196 }
1197 
1198 int
vlapic_read(struct vlapic * vlapic,int mmio_access,uint64_t offset,uint64_t * data,bool * retu)1199 vlapic_read(struct vlapic *vlapic, int mmio_access, uint64_t offset,
1200     uint64_t *data, bool *retu)
1201 {
1202 	struct LAPIC	*lapic = vlapic->apic_page;
1203 	uint32_t	*reg;
1204 	int		 i;
1205 
1206 	/* Ignore MMIO accesses in x2APIC mode */
1207 	if (x2apic(vlapic) && mmio_access) {
1208 		VLAPIC_CTR1(vlapic, "MMIO read from offset %#lx in x2APIC mode",
1209 		    offset);
1210 		*data = 0;
1211 		goto done;
1212 	}
1213 
1214 	if (!x2apic(vlapic) && !mmio_access) {
1215 		/*
1216 		 * XXX Generate GP fault for MSR accesses in xAPIC mode
1217 		 */
1218 		VLAPIC_CTR1(vlapic, "x2APIC MSR read from offset %#lx in "
1219 		    "xAPIC mode", offset);
1220 		*data = 0;
1221 		goto done;
1222 	}
1223 
1224 	if (offset > sizeof(*lapic)) {
1225 		*data = 0;
1226 		goto done;
1227 	}
1228 
1229 	offset &= ~3;
1230 	switch(offset)
1231 	{
1232 		case APIC_OFFSET_ID:
1233 			*data = lapic->id;
1234 			break;
1235 		case APIC_OFFSET_VER:
1236 			*data = lapic->version;
1237 			break;
1238 		case APIC_OFFSET_TPR:
1239 			*data = vlapic_get_tpr(vlapic);
1240 			break;
1241 		case APIC_OFFSET_APR:
1242 			*data = lapic->apr;
1243 			break;
1244 		case APIC_OFFSET_PPR:
1245 			*data = lapic->ppr;
1246 			break;
1247 		case APIC_OFFSET_EOI:
1248 			*data = lapic->eoi;
1249 			break;
1250 		case APIC_OFFSET_LDR:
1251 			*data = lapic->ldr;
1252 			break;
1253 		case APIC_OFFSET_DFR:
1254 			*data = lapic->dfr;
1255 			break;
1256 		case APIC_OFFSET_SVR:
1257 			*data = lapic->svr;
1258 			break;
1259 		case APIC_OFFSET_ISR0 ... APIC_OFFSET_ISR7:
1260 			i = (offset - APIC_OFFSET_ISR0) >> 2;
1261 			reg = &lapic->isr0;
1262 			*data = *(reg + i);
1263 			break;
1264 		case APIC_OFFSET_TMR0 ... APIC_OFFSET_TMR7:
1265 			i = (offset - APIC_OFFSET_TMR0) >> 2;
1266 			reg = &lapic->tmr0;
1267 			*data = *(reg + i);
1268 			break;
1269 		case APIC_OFFSET_IRR0 ... APIC_OFFSET_IRR7:
1270 			i = (offset - APIC_OFFSET_IRR0) >> 2;
1271 			reg = &lapic->irr0;
1272 			*data = atomic_load_acq_int(reg + i);
1273 			break;
1274 		case APIC_OFFSET_ESR:
1275 			*data = lapic->esr;
1276 			break;
1277 		case APIC_OFFSET_ICR_LOW:
1278 			*data = lapic->icr_lo;
1279 			if (x2apic(vlapic))
1280 				*data |= (uint64_t)lapic->icr_hi << 32;
1281 			break;
1282 		case APIC_OFFSET_ICR_HI:
1283 			*data = lapic->icr_hi;
1284 			break;
1285 		case APIC_OFFSET_CMCI_LVT:
1286 		case APIC_OFFSET_TIMER_LVT ... APIC_OFFSET_ERROR_LVT:
1287 			*data = vlapic_get_lvt(vlapic, offset);
1288 #ifdef INVARIANTS
1289 			reg = vlapic_get_lvtptr(vlapic, offset);
1290 			KASSERT(*data == *reg, ("inconsistent lvt value at "
1291 			    "offset %#lx: %#lx/%#x", offset, *data, *reg));
1292 #endif
1293 			break;
1294 		case APIC_OFFSET_TIMER_ICR:
1295 			*data = lapic->icr_timer;
1296 			break;
1297 		case APIC_OFFSET_TIMER_CCR:
1298 			*data = vlapic_get_ccr(vlapic);
1299 			break;
1300 		case APIC_OFFSET_TIMER_DCR:
1301 			*data = lapic->dcr_timer;
1302 			break;
1303 		case APIC_OFFSET_SELF_IPI:
1304 			/*
1305 			 * XXX generate a GP fault if vlapic is in x2apic mode
1306 			 */
1307 			*data = 0;
1308 			break;
1309 		case APIC_OFFSET_RRR:
1310 		default:
1311 			*data = 0;
1312 			break;
1313 	}
1314 done:
1315 	VLAPIC_CTR2(vlapic, "vlapic read offset %#x, data %#lx", offset, *data);
1316 	return 0;
1317 }
1318 
1319 int
vlapic_write(struct vlapic * vlapic,int mmio_access,uint64_t offset,uint64_t data,bool * retu)1320 vlapic_write(struct vlapic *vlapic, int mmio_access, uint64_t offset,
1321     uint64_t data, bool *retu)
1322 {
1323 	struct LAPIC	*lapic = vlapic->apic_page;
1324 	uint32_t	*regptr;
1325 	int		retval;
1326 
1327 	KASSERT((offset & 0xf) == 0 && offset < PAGE_SIZE,
1328 	    ("vlapic_write: invalid offset %#lx", offset));
1329 
1330 	VLAPIC_CTR2(vlapic, "vlapic write offset %#lx, data %#lx",
1331 	    offset, data);
1332 
1333 	if (offset > sizeof(*lapic))
1334 		return (0);
1335 
1336 	/* Ignore MMIO accesses in x2APIC mode */
1337 	if (x2apic(vlapic) && mmio_access) {
1338 		VLAPIC_CTR2(vlapic, "MMIO write of %#lx to offset %#lx "
1339 		    "in x2APIC mode", data, offset);
1340 		return (0);
1341 	}
1342 
1343 	/*
1344 	 * XXX Generate GP fault for MSR accesses in xAPIC mode
1345 	 */
1346 	if (!x2apic(vlapic) && !mmio_access) {
1347 		VLAPIC_CTR2(vlapic, "x2APIC MSR write of %#lx to offset %#lx "
1348 		    "in xAPIC mode", data, offset);
1349 		return (0);
1350 	}
1351 
1352 	retval = 0;
1353 	switch(offset)
1354 	{
1355 		case APIC_OFFSET_ID:
1356 			lapic->id = data;
1357 			vlapic_id_write_handler(vlapic);
1358 			break;
1359 		case APIC_OFFSET_TPR:
1360 			vlapic_set_tpr(vlapic, data & 0xff);
1361 			break;
1362 		case APIC_OFFSET_EOI:
1363 			vlapic_process_eoi(vlapic);
1364 			break;
1365 		case APIC_OFFSET_LDR:
1366 			lapic->ldr = data;
1367 			vlapic_ldr_write_handler(vlapic);
1368 			break;
1369 		case APIC_OFFSET_DFR:
1370 			lapic->dfr = data;
1371 			vlapic_dfr_write_handler(vlapic);
1372 			break;
1373 		case APIC_OFFSET_SVR:
1374 			lapic->svr = data;
1375 			vlapic_svr_write_handler(vlapic);
1376 			break;
1377 		case APIC_OFFSET_ICR_LOW:
1378 			lapic->icr_lo = data;
1379 			if (x2apic(vlapic))
1380 				lapic->icr_hi = data >> 32;
1381 			retval = vlapic_icrlo_write_handler(vlapic, retu);
1382 			break;
1383 		case APIC_OFFSET_ICR_HI:
1384 			lapic->icr_hi = data;
1385 			break;
1386 		case APIC_OFFSET_CMCI_LVT:
1387 		case APIC_OFFSET_TIMER_LVT ... APIC_OFFSET_ERROR_LVT:
1388 			regptr = vlapic_get_lvtptr(vlapic, offset);
1389 			*regptr = data;
1390 			vlapic_lvt_write_handler(vlapic, offset);
1391 			break;
1392 		case APIC_OFFSET_TIMER_ICR:
1393 			lapic->icr_timer = data;
1394 			vlapic_icrtmr_write_handler(vlapic);
1395 			break;
1396 
1397 		case APIC_OFFSET_TIMER_DCR:
1398 			lapic->dcr_timer = data;
1399 			vlapic_dcr_write_handler(vlapic);
1400 			break;
1401 
1402 		case APIC_OFFSET_ESR:
1403 			vlapic_esr_write_handler(vlapic);
1404 			break;
1405 
1406 		case APIC_OFFSET_SELF_IPI:
1407 			if (x2apic(vlapic))
1408 				vlapic_self_ipi_handler(vlapic, data);
1409 			break;
1410 
1411 		case APIC_OFFSET_VER:
1412 		case APIC_OFFSET_APR:
1413 		case APIC_OFFSET_PPR:
1414 		case APIC_OFFSET_RRR:
1415 		case APIC_OFFSET_ISR0 ... APIC_OFFSET_ISR7:
1416 		case APIC_OFFSET_TMR0 ... APIC_OFFSET_TMR7:
1417 		case APIC_OFFSET_IRR0 ... APIC_OFFSET_IRR7:
1418 		case APIC_OFFSET_TIMER_CCR:
1419 		default:
1420 			// Read only.
1421 			break;
1422 	}
1423 
1424 	return (retval);
1425 }
1426 
1427 static void
vlapic_reset(struct vlapic * vlapic)1428 vlapic_reset(struct vlapic *vlapic)
1429 {
1430 	struct LAPIC *lapic;
1431 
1432 	lapic = vlapic->apic_page;
1433 	bzero(lapic, sizeof(struct LAPIC));
1434 
1435 	lapic->id = vlapic_get_id(vlapic);
1436 	lapic->version = VLAPIC_VERSION;
1437 	lapic->version |= (VLAPIC_MAXLVT_INDEX << MAXLVTSHIFT);
1438 	lapic->dfr = 0xffffffff;
1439 	lapic->svr = APIC_SVR_VECTOR;
1440 	vlapic_mask_lvts(vlapic);
1441 	vlapic_reset_tmr(vlapic);
1442 
1443 	lapic->dcr_timer = 0;
1444 	vlapic_dcr_write_handler(vlapic);
1445 
1446 	if (vlapic->vcpuid == 0)
1447 		vlapic->boot_state = BS_RUNNING;	/* BSP */
1448 	else
1449 		vlapic->boot_state = BS_INIT;		/* AP */
1450 
1451 	vlapic->svr_last = lapic->svr;
1452 }
1453 
1454 void
vlapic_init(struct vlapic * vlapic)1455 vlapic_init(struct vlapic *vlapic)
1456 {
1457 	KASSERT(vlapic->vm != NULL, ("vlapic_init: vm is not initialized"));
1458 	KASSERT(vlapic->vcpuid >= 0 &&
1459 	    vlapic->vcpuid < vm_get_maxcpus(vlapic->vm),
1460 	    ("vlapic_init: vcpuid is not initialized"));
1461 	KASSERT(vlapic->apic_page != NULL, ("vlapic_init: apic_page is not "
1462 	    "initialized"));
1463 
1464 	/*
1465 	 * If the vlapic is configured in x2apic mode then it will be
1466 	 * accessed in the critical section via the MSR emulation code.
1467 	 *
1468 	 * Therefore the timer mutex must be a spinlock because blockable
1469 	 * mutexes cannot be acquired in a critical section.
1470 	 */
1471 	mtx_init(&vlapic->timer_mtx, "vlapic timer mtx", NULL, MTX_SPIN);
1472 	callout_init(&vlapic->callout, 1);
1473 
1474 	vlapic->msr_apicbase = DEFAULT_APIC_BASE | APICBASE_ENABLED;
1475 
1476 	if (vlapic->vcpuid == 0)
1477 		vlapic->msr_apicbase |= APICBASE_BSP;
1478 
1479 	vlapic_reset(vlapic);
1480 }
1481 
1482 void
vlapic_cleanup(struct vlapic * vlapic)1483 vlapic_cleanup(struct vlapic *vlapic)
1484 {
1485 
1486 	callout_drain(&vlapic->callout);
1487 }
1488 
1489 uint64_t
vlapic_get_apicbase(struct vlapic * vlapic)1490 vlapic_get_apicbase(struct vlapic *vlapic)
1491 {
1492 
1493 	return (vlapic->msr_apicbase);
1494 }
1495 
1496 int
vlapic_set_apicbase(struct vlapic * vlapic,uint64_t new)1497 vlapic_set_apicbase(struct vlapic *vlapic, uint64_t new)
1498 {
1499 
1500 	if (vlapic->msr_apicbase != new) {
1501 		VLAPIC_CTR2(vlapic, "Changing APIC_BASE MSR from %#lx to %#lx "
1502 		    "not supported", vlapic->msr_apicbase, new);
1503 		return (-1);
1504 	}
1505 
1506 	return (0);
1507 }
1508 
1509 void
vlapic_set_x2apic_state(struct vm * vm,int vcpuid,enum x2apic_state state)1510 vlapic_set_x2apic_state(struct vm *vm, int vcpuid, enum x2apic_state state)
1511 {
1512 	struct vlapic *vlapic;
1513 	struct LAPIC *lapic;
1514 
1515 	vlapic = vm_lapic(vm, vcpuid);
1516 
1517 	if (state == X2APIC_DISABLED)
1518 		vlapic->msr_apicbase &= ~APICBASE_X2APIC;
1519 	else
1520 		vlapic->msr_apicbase |= APICBASE_X2APIC;
1521 
1522 	/*
1523 	 * Reset the local APIC registers whose values are mode-dependent.
1524 	 *
1525 	 * XXX this works because the APIC mode can be changed only at vcpu
1526 	 * initialization time.
1527 	 */
1528 	lapic = vlapic->apic_page;
1529 	lapic->id = vlapic_get_id(vlapic);
1530 	if (x2apic(vlapic)) {
1531 		lapic->ldr = x2apic_ldr(vlapic);
1532 		lapic->dfr = 0;
1533 	} else {
1534 		lapic->ldr = 0;
1535 		lapic->dfr = 0xffffffff;
1536 	}
1537 
1538 	if (state == X2APIC_ENABLED) {
1539 		if (vlapic->ops.enable_x2apic_mode)
1540 			(*vlapic->ops.enable_x2apic_mode)(vlapic);
1541 	}
1542 }
1543 
1544 void
vlapic_deliver_intr(struct vm * vm,bool level,uint32_t dest,bool phys,int delmode,int vec)1545 vlapic_deliver_intr(struct vm *vm, bool level, uint32_t dest, bool phys,
1546     int delmode, int vec)
1547 {
1548 	bool lowprio;
1549 	int vcpuid;
1550 	cpuset_t dmask;
1551 
1552 	if (delmode != IOART_DELFIXED &&
1553 	    delmode != IOART_DELLOPRI &&
1554 	    delmode != IOART_DELEXINT) {
1555 		VM_CTR1(vm, "vlapic intr invalid delmode %#x", delmode);
1556 		return;
1557 	}
1558 	lowprio = (delmode == IOART_DELLOPRI);
1559 
1560 	/*
1561 	 * We don't provide any virtual interrupt redirection hardware so
1562 	 * all interrupts originating from the ioapic or MSI specify the
1563 	 * 'dest' in the legacy xAPIC format.
1564 	 */
1565 	vlapic_calcdest(vm, &dmask, dest, phys, lowprio, false);
1566 
1567 	while ((vcpuid = CPU_FFS(&dmask)) != 0) {
1568 		vcpuid--;
1569 		CPU_CLR(vcpuid, &dmask);
1570 		if (delmode == IOART_DELEXINT) {
1571 			vm_inject_extint(vm, vcpuid);
1572 		} else {
1573 			lapic_set_intr(vm, vcpuid, vec, level);
1574 		}
1575 	}
1576 }
1577 
1578 void
vlapic_post_intr(struct vlapic * vlapic,int hostcpu,int ipinum)1579 vlapic_post_intr(struct vlapic *vlapic, int hostcpu, int ipinum)
1580 {
1581 	/*
1582 	 * Post an interrupt to the vcpu currently running on 'hostcpu'.
1583 	 *
1584 	 * This is done by leveraging features like Posted Interrupts (Intel)
1585 	 * Doorbell MSR (AMD AVIC) that avoid a VM exit.
1586 	 *
1587 	 * If neither of these features are available then fallback to
1588 	 * sending an IPI to 'hostcpu'.
1589 	 */
1590 	if (vlapic->ops.post_intr)
1591 		(*vlapic->ops.post_intr)(vlapic, hostcpu);
1592 	else
1593 		ipi_cpu(hostcpu, ipinum);
1594 }
1595 
1596 bool
vlapic_enabled(struct vlapic * vlapic)1597 vlapic_enabled(struct vlapic *vlapic)
1598 {
1599 	struct LAPIC *lapic = vlapic->apic_page;
1600 
1601 	if ((vlapic->msr_apicbase & APICBASE_ENABLED) != 0 &&
1602 	    (lapic->svr & APIC_SVR_ENABLE) != 0)
1603 		return (true);
1604 	else
1605 		return (false);
1606 }
1607 
1608 static void
vlapic_set_tmr(struct vlapic * vlapic,int vector,bool level)1609 vlapic_set_tmr(struct vlapic *vlapic, int vector, bool level)
1610 {
1611 	struct LAPIC *lapic;
1612 	uint32_t *tmrptr, mask;
1613 	int idx;
1614 
1615 	lapic = vlapic->apic_page;
1616 	tmrptr = &lapic->tmr0;
1617 	idx = (vector / 32) * 4;
1618 	mask = 1 << (vector % 32);
1619 	if (level)
1620 		tmrptr[idx] |= mask;
1621 	else
1622 		tmrptr[idx] &= ~mask;
1623 
1624 	if (vlapic->ops.set_tmr != NULL)
1625 		(*vlapic->ops.set_tmr)(vlapic, vector, level);
1626 }
1627 
1628 void
vlapic_reset_tmr(struct vlapic * vlapic)1629 vlapic_reset_tmr(struct vlapic *vlapic)
1630 {
1631 	int vector;
1632 
1633 	VLAPIC_CTR0(vlapic, "vlapic resetting all vectors to edge-triggered");
1634 
1635 	for (vector = 0; vector <= 255; vector++)
1636 		vlapic_set_tmr(vlapic, vector, false);
1637 }
1638 
1639 void
vlapic_set_tmr_level(struct vlapic * vlapic,uint32_t dest,bool phys,int delmode,int vector)1640 vlapic_set_tmr_level(struct vlapic *vlapic, uint32_t dest, bool phys,
1641     int delmode, int vector)
1642 {
1643 	cpuset_t dmask;
1644 	bool lowprio;
1645 
1646 	KASSERT(vector >= 0 && vector <= 255, ("invalid vector %d", vector));
1647 
1648 	/*
1649 	 * A level trigger is valid only for fixed and lowprio delivery modes.
1650 	 */
1651 	if (delmode != APIC_DELMODE_FIXED && delmode != APIC_DELMODE_LOWPRIO) {
1652 		VLAPIC_CTR1(vlapic, "Ignoring level trigger-mode for "
1653 		    "delivery-mode %d", delmode);
1654 		return;
1655 	}
1656 
1657 	lowprio = (delmode == APIC_DELMODE_LOWPRIO);
1658 	vlapic_calcdest(vlapic->vm, &dmask, dest, phys, lowprio, false);
1659 
1660 	if (!CPU_ISSET(vlapic->vcpuid, &dmask))
1661 		return;
1662 
1663 	VLAPIC_CTR1(vlapic, "vector %d set to level-triggered", vector);
1664 	vlapic_set_tmr(vlapic, vector, true);
1665 }
1666