xref: /openbmc/linux/arch/x86/kvm/ioapic.c (revision bf0fb67c)
1 /*
2  *  Copyright (C) 2001  MandrakeSoft S.A.
3  *  Copyright 2010 Red Hat, Inc. and/or its affiliates.
4  *
5  *    MandrakeSoft S.A.
6  *    43, rue d'Aboukir
7  *    75002 Paris - France
8  *    http://www.linux-mandrake.com/
9  *    http://www.mandrakesoft.com/
10  *
11  *  This library is free software; you can redistribute it and/or
12  *  modify it under the terms of the GNU Lesser General Public
13  *  License as published by the Free Software Foundation; either
14  *  version 2 of the License, or (at your option) any later version.
15  *
16  *  This library is distributed in the hope that it will be useful,
17  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
18  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
19  *  Lesser General Public License for more details.
20  *
21  *  You should have received a copy of the GNU Lesser General Public
22  *  License along with this library; if not, write to the Free Software
23  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
24  *
25  *  Yunhong Jiang <yunhong.jiang@intel.com>
26  *  Yaozu (Eddie) Dong <eddie.dong@intel.com>
27  *  Based on Xen 3.1 code.
28  */
29 
30 #include <linux/kvm_host.h>
31 #include <linux/kvm.h>
32 #include <linux/mm.h>
33 #include <linux/highmem.h>
34 #include <linux/smp.h>
35 #include <linux/hrtimer.h>
36 #include <linux/io.h>
37 #include <linux/slab.h>
38 #include <linux/export.h>
39 #include <asm/processor.h>
40 #include <asm/page.h>
41 #include <asm/current.h>
42 #include <trace/events/kvm.h>
43 
44 #include "ioapic.h"
45 #include "lapic.h"
46 #include "irq.h"
47 
48 #if 0
49 #define ioapic_debug(fmt,arg...) printk(KERN_WARNING fmt,##arg)
50 #else
51 #define ioapic_debug(fmt, arg...)
52 #endif
53 static int ioapic_service(struct kvm_ioapic *vioapic, int irq,
54 		bool line_status);
55 
56 static unsigned long ioapic_read_indirect(struct kvm_ioapic *ioapic,
57 					  unsigned long addr,
58 					  unsigned long length)
59 {
60 	unsigned long result = 0;
61 
62 	switch (ioapic->ioregsel) {
63 	case IOAPIC_REG_VERSION:
64 		result = ((((IOAPIC_NUM_PINS - 1) & 0xff) << 16)
65 			  | (IOAPIC_VERSION_ID & 0xff));
66 		break;
67 
68 	case IOAPIC_REG_APIC_ID:
69 	case IOAPIC_REG_ARB_ID:
70 		result = ((ioapic->id & 0xf) << 24);
71 		break;
72 
73 	default:
74 		{
75 			u32 redir_index = (ioapic->ioregsel - 0x10) >> 1;
76 			u64 redir_content;
77 
78 			if (redir_index < IOAPIC_NUM_PINS)
79 				redir_content =
80 					ioapic->redirtbl[redir_index].bits;
81 			else
82 				redir_content = ~0ULL;
83 
84 			result = (ioapic->ioregsel & 0x1) ?
85 			    (redir_content >> 32) & 0xffffffff :
86 			    redir_content & 0xffffffff;
87 			break;
88 		}
89 	}
90 
91 	return result;
92 }
93 
94 static void rtc_irq_eoi_tracking_reset(struct kvm_ioapic *ioapic)
95 {
96 	ioapic->rtc_status.pending_eoi = 0;
97 	bitmap_zero(ioapic->rtc_status.dest_map, KVM_MAX_VCPUS);
98 }
99 
100 static void kvm_rtc_eoi_tracking_restore_all(struct kvm_ioapic *ioapic);
101 
102 static void rtc_status_pending_eoi_check_valid(struct kvm_ioapic *ioapic)
103 {
104 	if (WARN_ON(ioapic->rtc_status.pending_eoi < 0))
105 		kvm_rtc_eoi_tracking_restore_all(ioapic);
106 }
107 
108 static void __rtc_irq_eoi_tracking_restore_one(struct kvm_vcpu *vcpu)
109 {
110 	bool new_val, old_val;
111 	struct kvm_ioapic *ioapic = vcpu->kvm->arch.vioapic;
112 	union kvm_ioapic_redirect_entry *e;
113 
114 	e = &ioapic->redirtbl[RTC_GSI];
115 	if (!kvm_apic_match_dest(vcpu, NULL, 0,	e->fields.dest_id,
116 				e->fields.dest_mode))
117 		return;
118 
119 	new_val = kvm_apic_pending_eoi(vcpu, e->fields.vector);
120 	old_val = test_bit(vcpu->vcpu_id, ioapic->rtc_status.dest_map);
121 
122 	if (new_val == old_val)
123 		return;
124 
125 	if (new_val) {
126 		__set_bit(vcpu->vcpu_id, ioapic->rtc_status.dest_map);
127 		ioapic->rtc_status.pending_eoi++;
128 	} else {
129 		__clear_bit(vcpu->vcpu_id, ioapic->rtc_status.dest_map);
130 		ioapic->rtc_status.pending_eoi--;
131 		rtc_status_pending_eoi_check_valid(ioapic);
132 	}
133 }
134 
135 void kvm_rtc_eoi_tracking_restore_one(struct kvm_vcpu *vcpu)
136 {
137 	struct kvm_ioapic *ioapic = vcpu->kvm->arch.vioapic;
138 
139 	spin_lock(&ioapic->lock);
140 	__rtc_irq_eoi_tracking_restore_one(vcpu);
141 	spin_unlock(&ioapic->lock);
142 }
143 
144 static void kvm_rtc_eoi_tracking_restore_all(struct kvm_ioapic *ioapic)
145 {
146 	struct kvm_vcpu *vcpu;
147 	int i;
148 
149 	if (RTC_GSI >= IOAPIC_NUM_PINS)
150 		return;
151 
152 	rtc_irq_eoi_tracking_reset(ioapic);
153 	kvm_for_each_vcpu(i, vcpu, ioapic->kvm)
154 	    __rtc_irq_eoi_tracking_restore_one(vcpu);
155 }
156 
157 static void rtc_irq_eoi(struct kvm_ioapic *ioapic, struct kvm_vcpu *vcpu)
158 {
159 	if (test_and_clear_bit(vcpu->vcpu_id, ioapic->rtc_status.dest_map)) {
160 		--ioapic->rtc_status.pending_eoi;
161 		rtc_status_pending_eoi_check_valid(ioapic);
162 	}
163 }
164 
165 static bool rtc_irq_check_coalesced(struct kvm_ioapic *ioapic)
166 {
167 	if (ioapic->rtc_status.pending_eoi > 0)
168 		return true; /* coalesced */
169 
170 	return false;
171 }
172 
173 static int ioapic_set_irq(struct kvm_ioapic *ioapic, unsigned int irq,
174 		int irq_level, bool line_status)
175 {
176 	union kvm_ioapic_redirect_entry entry;
177 	u32 mask = 1 << irq;
178 	u32 old_irr;
179 	int edge, ret;
180 
181 	entry = ioapic->redirtbl[irq];
182 	edge = (entry.fields.trig_mode == IOAPIC_EDGE_TRIG);
183 
184 	if (!irq_level) {
185 		ioapic->irr &= ~mask;
186 		ret = 1;
187 		goto out;
188 	}
189 
190 	/*
191 	 * Return 0 for coalesced interrupts; for edge-triggered interrupts,
192 	 * this only happens if a previous edge has not been delivered due
193 	 * do masking.  For level interrupts, the remote_irr field tells
194 	 * us if the interrupt is waiting for an EOI.
195 	 *
196 	 * RTC is special: it is edge-triggered, but userspace likes to know
197 	 * if it has been already ack-ed via EOI because coalesced RTC
198 	 * interrupts lead to time drift in Windows guests.  So we track
199 	 * EOI manually for the RTC interrupt.
200 	 */
201 	if (irq == RTC_GSI && line_status &&
202 		rtc_irq_check_coalesced(ioapic)) {
203 		ret = 0;
204 		goto out;
205 	}
206 
207 	old_irr = ioapic->irr;
208 	ioapic->irr |= mask;
209 	if (edge)
210 		ioapic->irr_delivered &= ~mask;
211 	if ((edge && old_irr == ioapic->irr) ||
212 	    (!edge && entry.fields.remote_irr)) {
213 		ret = 0;
214 		goto out;
215 	}
216 
217 	ret = ioapic_service(ioapic, irq, line_status);
218 
219 out:
220 	trace_kvm_ioapic_set_irq(entry.bits, irq, ret == 0);
221 	return ret;
222 }
223 
224 static void kvm_ioapic_inject_all(struct kvm_ioapic *ioapic, unsigned long irr)
225 {
226 	u32 idx;
227 
228 	rtc_irq_eoi_tracking_reset(ioapic);
229 	for_each_set_bit(idx, &irr, IOAPIC_NUM_PINS)
230 		ioapic_set_irq(ioapic, idx, 1, true);
231 
232 	kvm_rtc_eoi_tracking_restore_all(ioapic);
233 }
234 
235 
236 static void update_handled_vectors(struct kvm_ioapic *ioapic)
237 {
238 	DECLARE_BITMAP(handled_vectors, 256);
239 	int i;
240 
241 	memset(handled_vectors, 0, sizeof(handled_vectors));
242 	for (i = 0; i < IOAPIC_NUM_PINS; ++i)
243 		__set_bit(ioapic->redirtbl[i].fields.vector, handled_vectors);
244 	memcpy(ioapic->handled_vectors, handled_vectors,
245 	       sizeof(handled_vectors));
246 	smp_wmb();
247 }
248 
249 void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap,
250 			u32 *tmr)
251 {
252 	struct kvm_ioapic *ioapic = vcpu->kvm->arch.vioapic;
253 	union kvm_ioapic_redirect_entry *e;
254 	int index;
255 
256 	spin_lock(&ioapic->lock);
257 	for (index = 0; index < IOAPIC_NUM_PINS; index++) {
258 		e = &ioapic->redirtbl[index];
259 		if (e->fields.trig_mode == IOAPIC_LEVEL_TRIG ||
260 		    kvm_irq_has_notifier(ioapic->kvm, KVM_IRQCHIP_IOAPIC, index) ||
261 		    index == RTC_GSI) {
262 			if (kvm_apic_match_dest(vcpu, NULL, 0,
263 				e->fields.dest_id, e->fields.dest_mode)) {
264 				__set_bit(e->fields.vector,
265 					(unsigned long *)eoi_exit_bitmap);
266 				if (e->fields.trig_mode == IOAPIC_LEVEL_TRIG)
267 					__set_bit(e->fields.vector,
268 						(unsigned long *)tmr);
269 			}
270 		}
271 	}
272 	spin_unlock(&ioapic->lock);
273 }
274 
275 void kvm_vcpu_request_scan_ioapic(struct kvm *kvm)
276 {
277 	struct kvm_ioapic *ioapic = kvm->arch.vioapic;
278 
279 	if (!ioapic)
280 		return;
281 	kvm_make_scan_ioapic_request(kvm);
282 }
283 
284 static void ioapic_write_indirect(struct kvm_ioapic *ioapic, u32 val)
285 {
286 	unsigned index;
287 	bool mask_before, mask_after;
288 	union kvm_ioapic_redirect_entry *e;
289 
290 	switch (ioapic->ioregsel) {
291 	case IOAPIC_REG_VERSION:
292 		/* Writes are ignored. */
293 		break;
294 
295 	case IOAPIC_REG_APIC_ID:
296 		ioapic->id = (val >> 24) & 0xf;
297 		break;
298 
299 	case IOAPIC_REG_ARB_ID:
300 		break;
301 
302 	default:
303 		index = (ioapic->ioregsel - 0x10) >> 1;
304 
305 		ioapic_debug("change redir index %x val %x\n", index, val);
306 		if (index >= IOAPIC_NUM_PINS)
307 			return;
308 		e = &ioapic->redirtbl[index];
309 		mask_before = e->fields.mask;
310 		if (ioapic->ioregsel & 1) {
311 			e->bits &= 0xffffffff;
312 			e->bits |= (u64) val << 32;
313 		} else {
314 			e->bits &= ~0xffffffffULL;
315 			e->bits |= (u32) val;
316 			e->fields.remote_irr = 0;
317 		}
318 		update_handled_vectors(ioapic);
319 		mask_after = e->fields.mask;
320 		if (mask_before != mask_after)
321 			kvm_fire_mask_notifiers(ioapic->kvm, KVM_IRQCHIP_IOAPIC, index, mask_after);
322 		if (e->fields.trig_mode == IOAPIC_LEVEL_TRIG
323 		    && ioapic->irr & (1 << index))
324 			ioapic_service(ioapic, index, false);
325 		kvm_vcpu_request_scan_ioapic(ioapic->kvm);
326 		break;
327 	}
328 }
329 
330 static int ioapic_service(struct kvm_ioapic *ioapic, int irq, bool line_status)
331 {
332 	union kvm_ioapic_redirect_entry *entry = &ioapic->redirtbl[irq];
333 	struct kvm_lapic_irq irqe;
334 	int ret;
335 
336 	if (entry->fields.mask)
337 		return -1;
338 
339 	ioapic_debug("dest=%x dest_mode=%x delivery_mode=%x "
340 		     "vector=%x trig_mode=%x\n",
341 		     entry->fields.dest_id, entry->fields.dest_mode,
342 		     entry->fields.delivery_mode, entry->fields.vector,
343 		     entry->fields.trig_mode);
344 
345 	irqe.dest_id = entry->fields.dest_id;
346 	irqe.vector = entry->fields.vector;
347 	irqe.dest_mode = entry->fields.dest_mode;
348 	irqe.trig_mode = entry->fields.trig_mode;
349 	irqe.delivery_mode = entry->fields.delivery_mode << 8;
350 	irqe.level = 1;
351 	irqe.shorthand = 0;
352 
353 	if (irqe.trig_mode == IOAPIC_EDGE_TRIG)
354 		ioapic->irr_delivered |= 1 << irq;
355 
356 	if (irq == RTC_GSI && line_status) {
357 		/*
358 		 * pending_eoi cannot ever become negative (see
359 		 * rtc_status_pending_eoi_check_valid) and the caller
360 		 * ensures that it is only called if it is >= zero, namely
361 		 * if rtc_irq_check_coalesced returns false).
362 		 */
363 		BUG_ON(ioapic->rtc_status.pending_eoi != 0);
364 		ret = kvm_irq_delivery_to_apic(ioapic->kvm, NULL, &irqe,
365 				ioapic->rtc_status.dest_map);
366 		ioapic->rtc_status.pending_eoi = (ret < 0 ? 0 : ret);
367 	} else
368 		ret = kvm_irq_delivery_to_apic(ioapic->kvm, NULL, &irqe, NULL);
369 
370 	if (ret && irqe.trig_mode == IOAPIC_LEVEL_TRIG)
371 		entry->fields.remote_irr = 1;
372 
373 	return ret;
374 }
375 
376 int kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int irq_source_id,
377 		       int level, bool line_status)
378 {
379 	int ret, irq_level;
380 
381 	BUG_ON(irq < 0 || irq >= IOAPIC_NUM_PINS);
382 
383 	spin_lock(&ioapic->lock);
384 	irq_level = __kvm_irq_line_state(&ioapic->irq_states[irq],
385 					 irq_source_id, level);
386 	ret = ioapic_set_irq(ioapic, irq, irq_level, line_status);
387 
388 	spin_unlock(&ioapic->lock);
389 
390 	return ret;
391 }
392 
393 void kvm_ioapic_clear_all(struct kvm_ioapic *ioapic, int irq_source_id)
394 {
395 	int i;
396 
397 	spin_lock(&ioapic->lock);
398 	for (i = 0; i < KVM_IOAPIC_NUM_PINS; i++)
399 		__clear_bit(irq_source_id, &ioapic->irq_states[i]);
400 	spin_unlock(&ioapic->lock);
401 }
402 
403 static void kvm_ioapic_eoi_inject_work(struct work_struct *work)
404 {
405 	int i;
406 	struct kvm_ioapic *ioapic = container_of(work, struct kvm_ioapic,
407 						 eoi_inject.work);
408 	spin_lock(&ioapic->lock);
409 	for (i = 0; i < IOAPIC_NUM_PINS; i++) {
410 		union kvm_ioapic_redirect_entry *ent = &ioapic->redirtbl[i];
411 
412 		if (ent->fields.trig_mode != IOAPIC_LEVEL_TRIG)
413 			continue;
414 
415 		if (ioapic->irr & (1 << i) && !ent->fields.remote_irr)
416 			ioapic_service(ioapic, i, false);
417 	}
418 	spin_unlock(&ioapic->lock);
419 }
420 
421 #define IOAPIC_SUCCESSIVE_IRQ_MAX_COUNT 10000
422 
423 static void __kvm_ioapic_update_eoi(struct kvm_vcpu *vcpu,
424 			struct kvm_ioapic *ioapic, int vector, int trigger_mode)
425 {
426 	int i;
427 
428 	for (i = 0; i < IOAPIC_NUM_PINS; i++) {
429 		union kvm_ioapic_redirect_entry *ent = &ioapic->redirtbl[i];
430 
431 		if (ent->fields.vector != vector)
432 			continue;
433 
434 		if (i == RTC_GSI)
435 			rtc_irq_eoi(ioapic, vcpu);
436 		/*
437 		 * We are dropping lock while calling ack notifiers because ack
438 		 * notifier callbacks for assigned devices call into IOAPIC
439 		 * recursively. Since remote_irr is cleared only after call
440 		 * to notifiers if the same vector will be delivered while lock
441 		 * is dropped it will be put into irr and will be delivered
442 		 * after ack notifier returns.
443 		 */
444 		spin_unlock(&ioapic->lock);
445 		kvm_notify_acked_irq(ioapic->kvm, KVM_IRQCHIP_IOAPIC, i);
446 		spin_lock(&ioapic->lock);
447 
448 		if (trigger_mode != IOAPIC_LEVEL_TRIG)
449 			continue;
450 
451 		ASSERT(ent->fields.trig_mode == IOAPIC_LEVEL_TRIG);
452 		ent->fields.remote_irr = 0;
453 		if (!ent->fields.mask && (ioapic->irr & (1 << i))) {
454 			++ioapic->irq_eoi[i];
455 			if (ioapic->irq_eoi[i] == IOAPIC_SUCCESSIVE_IRQ_MAX_COUNT) {
456 				/*
457 				 * Real hardware does not deliver the interrupt
458 				 * immediately during eoi broadcast, and this
459 				 * lets a buggy guest make slow progress
460 				 * even if it does not correctly handle a
461 				 * level-triggered interrupt.  Emulate this
462 				 * behavior if we detect an interrupt storm.
463 				 */
464 				schedule_delayed_work(&ioapic->eoi_inject, HZ / 100);
465 				ioapic->irq_eoi[i] = 0;
466 				trace_kvm_ioapic_delayed_eoi_inj(ent->bits);
467 			} else {
468 				ioapic_service(ioapic, i, false);
469 			}
470 		} else {
471 			ioapic->irq_eoi[i] = 0;
472 		}
473 	}
474 }
475 
476 void kvm_ioapic_update_eoi(struct kvm_vcpu *vcpu, int vector, int trigger_mode)
477 {
478 	struct kvm_ioapic *ioapic = vcpu->kvm->arch.vioapic;
479 
480 	spin_lock(&ioapic->lock);
481 	__kvm_ioapic_update_eoi(vcpu, ioapic, vector, trigger_mode);
482 	spin_unlock(&ioapic->lock);
483 }
484 
485 static inline struct kvm_ioapic *to_ioapic(struct kvm_io_device *dev)
486 {
487 	return container_of(dev, struct kvm_ioapic, dev);
488 }
489 
490 static inline int ioapic_in_range(struct kvm_ioapic *ioapic, gpa_t addr)
491 {
492 	return ((addr >= ioapic->base_address &&
493 		 (addr < ioapic->base_address + IOAPIC_MEM_LENGTH)));
494 }
495 
496 static int ioapic_mmio_read(struct kvm_vcpu *vcpu, struct kvm_io_device *this,
497 				gpa_t addr, int len, void *val)
498 {
499 	struct kvm_ioapic *ioapic = to_ioapic(this);
500 	u32 result;
501 	if (!ioapic_in_range(ioapic, addr))
502 		return -EOPNOTSUPP;
503 
504 	ioapic_debug("addr %lx\n", (unsigned long)addr);
505 	ASSERT(!(addr & 0xf));	/* check alignment */
506 
507 	addr &= 0xff;
508 	spin_lock(&ioapic->lock);
509 	switch (addr) {
510 	case IOAPIC_REG_SELECT:
511 		result = ioapic->ioregsel;
512 		break;
513 
514 	case IOAPIC_REG_WINDOW:
515 		result = ioapic_read_indirect(ioapic, addr, len);
516 		break;
517 
518 	default:
519 		result = 0;
520 		break;
521 	}
522 	spin_unlock(&ioapic->lock);
523 
524 	switch (len) {
525 	case 8:
526 		*(u64 *) val = result;
527 		break;
528 	case 1:
529 	case 2:
530 	case 4:
531 		memcpy(val, (char *)&result, len);
532 		break;
533 	default:
534 		printk(KERN_WARNING "ioapic: wrong length %d\n", len);
535 	}
536 	return 0;
537 }
538 
539 static int ioapic_mmio_write(struct kvm_vcpu *vcpu, struct kvm_io_device *this,
540 				 gpa_t addr, int len, const void *val)
541 {
542 	struct kvm_ioapic *ioapic = to_ioapic(this);
543 	u32 data;
544 	if (!ioapic_in_range(ioapic, addr))
545 		return -EOPNOTSUPP;
546 
547 	ioapic_debug("ioapic_mmio_write addr=%p len=%d val=%p\n",
548 		     (void*)addr, len, val);
549 	ASSERT(!(addr & 0xf));	/* check alignment */
550 
551 	switch (len) {
552 	case 8:
553 	case 4:
554 		data = *(u32 *) val;
555 		break;
556 	case 2:
557 		data = *(u16 *) val;
558 		break;
559 	case 1:
560 		data = *(u8  *) val;
561 		break;
562 	default:
563 		printk(KERN_WARNING "ioapic: Unsupported size %d\n", len);
564 		return 0;
565 	}
566 
567 	addr &= 0xff;
568 	spin_lock(&ioapic->lock);
569 	switch (addr) {
570 	case IOAPIC_REG_SELECT:
571 		ioapic->ioregsel = data & 0xFF; /* 8-bit register */
572 		break;
573 
574 	case IOAPIC_REG_WINDOW:
575 		ioapic_write_indirect(ioapic, data);
576 		break;
577 
578 	default:
579 		break;
580 	}
581 	spin_unlock(&ioapic->lock);
582 	return 0;
583 }
584 
585 static void kvm_ioapic_reset(struct kvm_ioapic *ioapic)
586 {
587 	int i;
588 
589 	cancel_delayed_work_sync(&ioapic->eoi_inject);
590 	for (i = 0; i < IOAPIC_NUM_PINS; i++)
591 		ioapic->redirtbl[i].fields.mask = 1;
592 	ioapic->base_address = IOAPIC_DEFAULT_BASE_ADDRESS;
593 	ioapic->ioregsel = 0;
594 	ioapic->irr = 0;
595 	ioapic->irr_delivered = 0;
596 	ioapic->id = 0;
597 	memset(ioapic->irq_eoi, 0x00, IOAPIC_NUM_PINS);
598 	rtc_irq_eoi_tracking_reset(ioapic);
599 	update_handled_vectors(ioapic);
600 }
601 
602 static const struct kvm_io_device_ops ioapic_mmio_ops = {
603 	.read     = ioapic_mmio_read,
604 	.write    = ioapic_mmio_write,
605 };
606 
607 int kvm_ioapic_init(struct kvm *kvm)
608 {
609 	struct kvm_ioapic *ioapic;
610 	int ret;
611 
612 	ioapic = kzalloc(sizeof(struct kvm_ioapic), GFP_KERNEL);
613 	if (!ioapic)
614 		return -ENOMEM;
615 	spin_lock_init(&ioapic->lock);
616 	INIT_DELAYED_WORK(&ioapic->eoi_inject, kvm_ioapic_eoi_inject_work);
617 	kvm->arch.vioapic = ioapic;
618 	kvm_ioapic_reset(ioapic);
619 	kvm_iodevice_init(&ioapic->dev, &ioapic_mmio_ops);
620 	ioapic->kvm = kvm;
621 	mutex_lock(&kvm->slots_lock);
622 	ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, ioapic->base_address,
623 				      IOAPIC_MEM_LENGTH, &ioapic->dev);
624 	mutex_unlock(&kvm->slots_lock);
625 	if (ret < 0) {
626 		kvm->arch.vioapic = NULL;
627 		kfree(ioapic);
628 	}
629 
630 	return ret;
631 }
632 
633 void kvm_ioapic_destroy(struct kvm *kvm)
634 {
635 	struct kvm_ioapic *ioapic = kvm->arch.vioapic;
636 
637 	cancel_delayed_work_sync(&ioapic->eoi_inject);
638 	if (ioapic) {
639 		kvm_io_bus_unregister_dev(kvm, KVM_MMIO_BUS, &ioapic->dev);
640 		kvm->arch.vioapic = NULL;
641 		kfree(ioapic);
642 	}
643 }
644 
645 int kvm_get_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state)
646 {
647 	struct kvm_ioapic *ioapic = ioapic_irqchip(kvm);
648 	if (!ioapic)
649 		return -EINVAL;
650 
651 	spin_lock(&ioapic->lock);
652 	memcpy(state, ioapic, sizeof(struct kvm_ioapic_state));
653 	state->irr &= ~ioapic->irr_delivered;
654 	spin_unlock(&ioapic->lock);
655 	return 0;
656 }
657 
658 int kvm_set_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state)
659 {
660 	struct kvm_ioapic *ioapic = ioapic_irqchip(kvm);
661 	if (!ioapic)
662 		return -EINVAL;
663 
664 	spin_lock(&ioapic->lock);
665 	memcpy(ioapic, state, sizeof(struct kvm_ioapic_state));
666 	ioapic->irr = 0;
667 	ioapic->irr_delivered = 0;
668 	update_handled_vectors(ioapic);
669 	kvm_vcpu_request_scan_ioapic(kvm);
670 	kvm_ioapic_inject_all(ioapic, state->irr);
671 	spin_unlock(&ioapic->lock);
672 	return 0;
673 }
674