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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
30
31#include <linux/kvm_host.h>
32#include <linux/kvm.h>
33#include <linux/mm.h>
34#include <linux/highmem.h>
35#include <linux/smp.h>
36#include <linux/hrtimer.h>
37#include <linux/io.h>
38#include <linux/slab.h>
39#include <linux/export.h>
40#include <linux/nospec.h>
41#include <asm/processor.h>
42#include <asm/page.h>
43#include <asm/current.h>
44#include <trace/events/kvm.h>
45
46#include "ioapic.h"
47#include "lapic.h"
48#include "irq.h"
49
50static int ioapic_service(struct kvm_ioapic *vioapic, int irq,
51 bool line_status);
52
53static void kvm_ioapic_update_eoi_one(struct kvm_vcpu *vcpu,
54 struct kvm_ioapic *ioapic,
55 int trigger_mode,
56 int pin);
57
58static unsigned long ioapic_read_indirect(struct kvm_ioapic *ioapic)
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 = ~0ULL;
77
78 if (redir_index < IOAPIC_NUM_PINS) {
79 u32 index = array_index_nospec(
80 redir_index, IOAPIC_NUM_PINS);
81
82 redir_content = ioapic->redirtbl[index].bits;
83 }
84
85 result = (ioapic->ioregsel & 0x1) ?
86 (redir_content >> 32) & 0xffffffff :
87 redir_content & 0xffffffff;
88 break;
89 }
90 }
91
92 return result;
93}
94
95static void rtc_irq_eoi_tracking_reset(struct kvm_ioapic *ioapic)
96{
97 ioapic->rtc_status.pending_eoi = 0;
98 bitmap_zero(dst: ioapic->rtc_status.dest_map.map, KVM_MAX_VCPU_IDS);
99}
100
101static void kvm_rtc_eoi_tracking_restore_all(struct kvm_ioapic *ioapic);
102
103static void rtc_status_pending_eoi_check_valid(struct kvm_ioapic *ioapic)
104{
105 if (WARN_ON(ioapic->rtc_status.pending_eoi < 0))
106 kvm_rtc_eoi_tracking_restore_all(ioapic);
107}
108
109static void __rtc_irq_eoi_tracking_restore_one(struct kvm_vcpu *vcpu)
110{
111 bool new_val, old_val;
112 struct kvm_ioapic *ioapic = vcpu->kvm->arch.vioapic;
113 struct dest_map *dest_map = &ioapic->rtc_status.dest_map;
114 union kvm_ioapic_redirect_entry *e;
115
116 e = &ioapic->redirtbl[RTC_GSI];
117 if (!kvm_apic_match_dest(vcpu, NULL, APIC_DEST_NOSHORT,
118 dest: e->fields.dest_id,
119 dest_mode: kvm_lapic_irq_dest_mode(dest_mode_logical: !!e->fields.dest_mode)))
120 return;
121
122 new_val = kvm_apic_pending_eoi(vcpu, vector: e->fields.vector);
123 old_val = test_bit(vcpu->vcpu_id, dest_map->map);
124
125 if (new_val == old_val)
126 return;
127
128 if (new_val) {
129 __set_bit(vcpu->vcpu_id, dest_map->map);
130 dest_map->vectors[vcpu->vcpu_id] = e->fields.vector;
131 ioapic->rtc_status.pending_eoi++;
132 } else {
133 __clear_bit(vcpu->vcpu_id, dest_map->map);
134 ioapic->rtc_status.pending_eoi--;
135 rtc_status_pending_eoi_check_valid(ioapic);
136 }
137}
138
139void kvm_rtc_eoi_tracking_restore_one(struct kvm_vcpu *vcpu)
140{
141 struct kvm_ioapic *ioapic = vcpu->kvm->arch.vioapic;
142
143 spin_lock(lock: &ioapic->lock);
144 __rtc_irq_eoi_tracking_restore_one(vcpu);
145 spin_unlock(lock: &ioapic->lock);
146}
147
148static void kvm_rtc_eoi_tracking_restore_all(struct kvm_ioapic *ioapic)
149{
150 struct kvm_vcpu *vcpu;
151 unsigned long i;
152
153 if (RTC_GSI >= IOAPIC_NUM_PINS)
154 return;
155
156 rtc_irq_eoi_tracking_reset(ioapic);
157 kvm_for_each_vcpu(i, vcpu, ioapic->kvm)
158 __rtc_irq_eoi_tracking_restore_one(vcpu);
159}
160
161static void rtc_irq_eoi(struct kvm_ioapic *ioapic, struct kvm_vcpu *vcpu,
162 int vector)
163{
164 struct dest_map *dest_map = &ioapic->rtc_status.dest_map;
165
166 /* RTC special handling */
167 if (test_bit(vcpu->vcpu_id, dest_map->map) &&
168 (vector == dest_map->vectors[vcpu->vcpu_id]) &&
169 (test_and_clear_bit(nr: vcpu->vcpu_id,
170 addr: ioapic->rtc_status.dest_map.map))) {
171 --ioapic->rtc_status.pending_eoi;
172 rtc_status_pending_eoi_check_valid(ioapic);
173 }
174}
175
176static bool rtc_irq_check_coalesced(struct kvm_ioapic *ioapic)
177{
178 if (ioapic->rtc_status.pending_eoi > 0)
179 return true; /* coalesced */
180
181 return false;
182}
183
184static void ioapic_lazy_update_eoi(struct kvm_ioapic *ioapic, int irq)
185{
186 unsigned long i;
187 struct kvm_vcpu *vcpu;
188 union kvm_ioapic_redirect_entry *entry = &ioapic->redirtbl[irq];
189
190 kvm_for_each_vcpu(i, vcpu, ioapic->kvm) {
191 if (!kvm_apic_match_dest(vcpu, NULL, APIC_DEST_NOSHORT,
192 dest: entry->fields.dest_id,
193 dest_mode: entry->fields.dest_mode) ||
194 kvm_apic_pending_eoi(vcpu, vector: entry->fields.vector))
195 continue;
196
197 /*
198 * If no longer has pending EOI in LAPICs, update
199 * EOI for this vector.
200 */
201 rtc_irq_eoi(ioapic, vcpu, vector: entry->fields.vector);
202 break;
203 }
204}
205
206static int ioapic_set_irq(struct kvm_ioapic *ioapic, unsigned int irq,
207 int irq_level, bool line_status)
208{
209 union kvm_ioapic_redirect_entry entry;
210 u32 mask = 1 << irq;
211 u32 old_irr;
212 int edge, ret;
213
214 entry = ioapic->redirtbl[irq];
215 edge = (entry.fields.trig_mode == IOAPIC_EDGE_TRIG);
216
217 if (!irq_level) {
218 ioapic->irr &= ~mask;
219 ret = 1;
220 goto out;
221 }
222
223 /*
224 * AMD SVM AVIC accelerate EOI write iff the interrupt is edge
225 * triggered, in which case the in-kernel IOAPIC will not be able
226 * to receive the EOI. In this case, we do a lazy update of the
227 * pending EOI when trying to set IOAPIC irq.
228 */
229 if (edge && kvm_apicv_activated(kvm: ioapic->kvm))
230 ioapic_lazy_update_eoi(ioapic, irq);
231
232 /*
233 * Return 0 for coalesced interrupts; for edge-triggered interrupts,
234 * this only happens if a previous edge has not been delivered due
235 * to masking. For level interrupts, the remote_irr field tells
236 * us if the interrupt is waiting for an EOI.
237 *
238 * RTC is special: it is edge-triggered, but userspace likes to know
239 * if it has been already ack-ed via EOI because coalesced RTC
240 * interrupts lead to time drift in Windows guests. So we track
241 * EOI manually for the RTC interrupt.
242 */
243 if (irq == RTC_GSI && line_status &&
244 rtc_irq_check_coalesced(ioapic)) {
245 ret = 0;
246 goto out;
247 }
248
249 old_irr = ioapic->irr;
250 ioapic->irr |= mask;
251 if (edge) {
252 ioapic->irr_delivered &= ~mask;
253 if (old_irr == ioapic->irr) {
254 ret = 0;
255 goto out;
256 }
257 }
258
259 ret = ioapic_service(vioapic: ioapic, irq, line_status);
260
261out:
262 trace_kvm_ioapic_set_irq(e: entry.bits, pin: irq, coalesced: ret == 0);
263 return ret;
264}
265
266static void kvm_ioapic_inject_all(struct kvm_ioapic *ioapic, unsigned long irr)
267{
268 u32 idx;
269
270 rtc_irq_eoi_tracking_reset(ioapic);
271 for_each_set_bit(idx, &irr, IOAPIC_NUM_PINS)
272 ioapic_set_irq(ioapic, irq: idx, irq_level: 1, line_status: true);
273
274 kvm_rtc_eoi_tracking_restore_all(ioapic);
275}
276
277
278void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, ulong *ioapic_handled_vectors)
279{
280 struct kvm_ioapic *ioapic = vcpu->kvm->arch.vioapic;
281 struct dest_map *dest_map = &ioapic->rtc_status.dest_map;
282 union kvm_ioapic_redirect_entry *e;
283 int index;
284
285 spin_lock(lock: &ioapic->lock);
286
287 /* Make sure we see any missing RTC EOI */
288 if (test_bit(vcpu->vcpu_id, dest_map->map))
289 __set_bit(dest_map->vectors[vcpu->vcpu_id],
290 ioapic_handled_vectors);
291
292 for (index = 0; index < IOAPIC_NUM_PINS; index++) {
293 e = &ioapic->redirtbl[index];
294 if (e->fields.trig_mode == IOAPIC_LEVEL_TRIG ||
295 kvm_irq_has_notifier(kvm: ioapic->kvm, KVM_IRQCHIP_IOAPIC, pin: index) ||
296 index == RTC_GSI) {
297 u16 dm = kvm_lapic_irq_dest_mode(dest_mode_logical: !!e->fields.dest_mode);
298
299 if (kvm_apic_match_dest(vcpu, NULL, APIC_DEST_NOSHORT,
300 dest: e->fields.dest_id, dest_mode: dm) ||
301 kvm_apic_pending_eoi(vcpu, vector: e->fields.vector))
302 __set_bit(e->fields.vector,
303 ioapic_handled_vectors);
304 }
305 }
306 spin_unlock(lock: &ioapic->lock);
307}
308
309void kvm_arch_post_irq_ack_notifier_list_update(struct kvm *kvm)
310{
311 if (!ioapic_in_kernel(kvm))
312 return;
313 kvm_make_scan_ioapic_request(kvm);
314}
315
316static void ioapic_write_indirect(struct kvm_ioapic *ioapic, u32 val)
317{
318 unsigned index;
319 bool mask_before, mask_after;
320 union kvm_ioapic_redirect_entry *e;
321 int old_remote_irr, old_delivery_status, old_dest_id, old_dest_mode;
322 DECLARE_BITMAP(vcpu_bitmap, KVM_MAX_VCPUS);
323
324 switch (ioapic->ioregsel) {
325 case IOAPIC_REG_VERSION:
326 /* Writes are ignored. */
327 break;
328
329 case IOAPIC_REG_APIC_ID:
330 ioapic->id = (val >> 24) & 0xf;
331 break;
332
333 case IOAPIC_REG_ARB_ID:
334 break;
335
336 default:
337 index = (ioapic->ioregsel - 0x10) >> 1;
338
339 if (index >= IOAPIC_NUM_PINS)
340 return;
341 index = array_index_nospec(index, IOAPIC_NUM_PINS);
342 e = &ioapic->redirtbl[index];
343 mask_before = e->fields.mask;
344 /* Preserve read-only fields */
345 old_remote_irr = e->fields.remote_irr;
346 old_delivery_status = e->fields.delivery_status;
347 old_dest_id = e->fields.dest_id;
348 old_dest_mode = e->fields.dest_mode;
349 if (ioapic->ioregsel & 1) {
350 e->bits &= 0xffffffff;
351 e->bits |= (u64) val << 32;
352 } else {
353 e->bits &= ~0xffffffffULL;
354 e->bits |= (u32) val;
355 }
356 e->fields.remote_irr = old_remote_irr;
357 e->fields.delivery_status = old_delivery_status;
358
359 /*
360 * Some OSes (Linux, Xen) assume that Remote IRR bit will
361 * be cleared by IOAPIC hardware when the entry is configured
362 * as edge-triggered. This behavior is used to simulate an
363 * explicit EOI on IOAPICs that don't have the EOI register.
364 */
365 if (e->fields.trig_mode == IOAPIC_EDGE_TRIG)
366 e->fields.remote_irr = 0;
367
368 mask_after = e->fields.mask;
369 if (mask_before != mask_after)
370 kvm_fire_mask_notifiers(kvm: ioapic->kvm, KVM_IRQCHIP_IOAPIC, pin: index, mask: mask_after);
371 if (e->fields.trig_mode == IOAPIC_LEVEL_TRIG &&
372 ioapic->irr & (1 << index) && !e->fields.mask && !e->fields.remote_irr) {
373 /*
374 * Pending status in irr may be outdated: the IRQ line may have
375 * already been deasserted by a device while the IRQ was masked.
376 * This occurs, for instance, if the interrupt is handled in a
377 * Linux guest as a oneshot interrupt (IRQF_ONESHOT). In this
378 * case the guest acknowledges the interrupt to the device in
379 * its threaded irq handler, i.e. after the EOI but before
380 * unmasking, so at the time of unmasking the IRQ line is
381 * already down but our pending irr bit is still set. In such
382 * cases, injecting this pending interrupt to the guest is
383 * buggy: the guest will receive an extra unwanted interrupt.
384 *
385 * So we need to check here if the IRQ is actually still pending.
386 * As we are generally not able to probe the IRQ line status
387 * directly, we do it through irqfd resampler. Namely, we clear
388 * the pending status and notify the resampler that this interrupt
389 * is done, without actually injecting it into the guest. If the
390 * IRQ line is actually already deasserted, we are done. If it is
391 * still asserted, a new interrupt will be shortly triggered
392 * through irqfd and injected into the guest.
393 *
394 * If, however, it's not possible to resample (no irqfd resampler
395 * registered for this irq), then unconditionally inject this
396 * pending interrupt into the guest, so the guest will not miss
397 * an interrupt, although may get an extra unwanted interrupt.
398 */
399 if (kvm_notify_irqfd_resampler(kvm: ioapic->kvm, KVM_IRQCHIP_IOAPIC, pin: index))
400 ioapic->irr &= ~(1 << index);
401 else
402 ioapic_service(vioapic: ioapic, irq: index, line_status: false);
403 }
404 if (e->fields.delivery_mode == APIC_DM_FIXED) {
405 struct kvm_lapic_irq irq;
406
407 irq.vector = e->fields.vector;
408 irq.delivery_mode = e->fields.delivery_mode << 8;
409 irq.dest_mode =
410 kvm_lapic_irq_dest_mode(dest_mode_logical: !!e->fields.dest_mode);
411 irq.level = false;
412 irq.trig_mode = e->fields.trig_mode;
413 irq.shorthand = APIC_DEST_NOSHORT;
414 irq.dest_id = e->fields.dest_id;
415 irq.msi_redir_hint = false;
416 bitmap_zero(dst: vcpu_bitmap, KVM_MAX_VCPUS);
417 kvm_bitmap_or_dest_vcpus(kvm: ioapic->kvm, irq: &irq,
418 vcpu_bitmap);
419 if (old_dest_mode != e->fields.dest_mode ||
420 old_dest_id != e->fields.dest_id) {
421 /*
422 * Update vcpu_bitmap with vcpus specified in
423 * the previous request as well. This is done to
424 * keep ioapic_handled_vectors synchronized.
425 */
426 irq.dest_id = old_dest_id;
427 irq.dest_mode =
428 kvm_lapic_irq_dest_mode(
429 dest_mode_logical: !!e->fields.dest_mode);
430 kvm_bitmap_or_dest_vcpus(kvm: ioapic->kvm, irq: &irq,
431 vcpu_bitmap);
432 }
433 kvm_make_scan_ioapic_request_mask(kvm: ioapic->kvm,
434 vcpu_bitmap);
435 } else {
436 kvm_make_scan_ioapic_request(kvm: ioapic->kvm);
437 }
438 break;
439 }
440}
441
442static int ioapic_service(struct kvm_ioapic *ioapic, int irq, bool line_status)
443{
444 union kvm_ioapic_redirect_entry *entry = &ioapic->redirtbl[irq];
445 struct kvm_lapic_irq irqe;
446 int ret;
447
448 if (entry->fields.mask ||
449 (entry->fields.trig_mode == IOAPIC_LEVEL_TRIG &&
450 entry->fields.remote_irr))
451 return -1;
452
453 irqe.dest_id = entry->fields.dest_id;
454 irqe.vector = entry->fields.vector;
455 irqe.dest_mode = kvm_lapic_irq_dest_mode(dest_mode_logical: !!entry->fields.dest_mode);
456 irqe.trig_mode = entry->fields.trig_mode;
457 irqe.delivery_mode = entry->fields.delivery_mode << 8;
458 irqe.level = 1;
459 irqe.shorthand = APIC_DEST_NOSHORT;
460 irqe.msi_redir_hint = false;
461
462 if (irqe.trig_mode == IOAPIC_EDGE_TRIG)
463 ioapic->irr_delivered |= 1 << irq;
464
465 if (irq == RTC_GSI && line_status) {
466 /*
467 * pending_eoi cannot ever become negative (see
468 * rtc_status_pending_eoi_check_valid) and the caller
469 * ensures that it is only called if it is >= zero, namely
470 * if rtc_irq_check_coalesced returns false).
471 */
472 BUG_ON(ioapic->rtc_status.pending_eoi != 0);
473 ret = kvm_irq_delivery_to_apic(kvm: ioapic->kvm, NULL, irq: &irqe,
474 dest_map: &ioapic->rtc_status.dest_map);
475 ioapic->rtc_status.pending_eoi = (ret < 0 ? 0 : ret);
476 } else
477 ret = kvm_irq_delivery_to_apic(kvm: ioapic->kvm, NULL, irq: &irqe, NULL);
478
479 if (ret && irqe.trig_mode == IOAPIC_LEVEL_TRIG)
480 entry->fields.remote_irr = 1;
481
482 return ret;
483}
484
485int kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int irq_source_id,
486 int level, bool line_status)
487{
488 int ret, irq_level;
489
490 BUG_ON(irq < 0 || irq >= IOAPIC_NUM_PINS);
491
492 spin_lock(lock: &ioapic->lock);
493 irq_level = __kvm_irq_line_state(irq_state: &ioapic->irq_states[irq],
494 irq_source_id, level);
495 ret = ioapic_set_irq(ioapic, irq, irq_level, line_status);
496
497 spin_unlock(lock: &ioapic->lock);
498
499 return ret;
500}
501
502void kvm_ioapic_clear_all(struct kvm_ioapic *ioapic, int irq_source_id)
503{
504 int i;
505
506 spin_lock(lock: &ioapic->lock);
507 for (i = 0; i < KVM_IOAPIC_NUM_PINS; i++)
508 __clear_bit(irq_source_id, &ioapic->irq_states[i]);
509 spin_unlock(lock: &ioapic->lock);
510}
511
512static void kvm_ioapic_eoi_inject_work(struct work_struct *work)
513{
514 int i;
515 struct kvm_ioapic *ioapic = container_of(work, struct kvm_ioapic,
516 eoi_inject.work);
517 spin_lock(lock: &ioapic->lock);
518 for (i = 0; i < IOAPIC_NUM_PINS; i++) {
519 union kvm_ioapic_redirect_entry *ent = &ioapic->redirtbl[i];
520
521 if (ent->fields.trig_mode != IOAPIC_LEVEL_TRIG)
522 continue;
523
524 if (ioapic->irr & (1 << i) && !ent->fields.remote_irr)
525 ioapic_service(ioapic, irq: i, line_status: false);
526 }
527 spin_unlock(lock: &ioapic->lock);
528}
529
530#define IOAPIC_SUCCESSIVE_IRQ_MAX_COUNT 10000
531static void kvm_ioapic_update_eoi_one(struct kvm_vcpu *vcpu,
532 struct kvm_ioapic *ioapic,
533 int trigger_mode,
534 int pin)
535{
536 struct kvm_lapic *apic = vcpu->arch.apic;
537 union kvm_ioapic_redirect_entry *ent = &ioapic->redirtbl[pin];
538
539 /*
540 * We are dropping lock while calling ack notifiers because ack
541 * notifier callbacks for assigned devices call into IOAPIC
542 * recursively. Since remote_irr is cleared only after call
543 * to notifiers if the same vector will be delivered while lock
544 * is dropped it will be put into irr and will be delivered
545 * after ack notifier returns.
546 */
547 spin_unlock(lock: &ioapic->lock);
548 kvm_notify_acked_irq(kvm: ioapic->kvm, KVM_IRQCHIP_IOAPIC, pin);
549 spin_lock(lock: &ioapic->lock);
550
551 if (trigger_mode != IOAPIC_LEVEL_TRIG ||
552 kvm_lapic_get_reg(apic, APIC_SPIV) & APIC_SPIV_DIRECTED_EOI)
553 return;
554
555 ASSERT(ent->fields.trig_mode == IOAPIC_LEVEL_TRIG);
556 ent->fields.remote_irr = 0;
557 if (!ent->fields.mask && (ioapic->irr & (1 << pin))) {
558 ++ioapic->irq_eoi[pin];
559 if (ioapic->irq_eoi[pin] == IOAPIC_SUCCESSIVE_IRQ_MAX_COUNT) {
560 /*
561 * Real hardware does not deliver the interrupt
562 * immediately during eoi broadcast, and this
563 * lets a buggy guest make slow progress
564 * even if it does not correctly handle a
565 * level-triggered interrupt. Emulate this
566 * behavior if we detect an interrupt storm.
567 */
568 schedule_delayed_work(dwork: &ioapic->eoi_inject, HZ / 100);
569 ioapic->irq_eoi[pin] = 0;
570 trace_kvm_ioapic_delayed_eoi_inj(e: ent->bits);
571 } else {
572 ioapic_service(ioapic, irq: pin, line_status: false);
573 }
574 } else {
575 ioapic->irq_eoi[pin] = 0;
576 }
577}
578
579void kvm_ioapic_update_eoi(struct kvm_vcpu *vcpu, int vector, int trigger_mode)
580{
581 int i;
582 struct kvm_ioapic *ioapic = vcpu->kvm->arch.vioapic;
583
584 spin_lock(lock: &ioapic->lock);
585 rtc_irq_eoi(ioapic, vcpu, vector);
586 for (i = 0; i < IOAPIC_NUM_PINS; i++) {
587 union kvm_ioapic_redirect_entry *ent = &ioapic->redirtbl[i];
588
589 if (ent->fields.vector != vector)
590 continue;
591 kvm_ioapic_update_eoi_one(vcpu, ioapic, trigger_mode, pin: i);
592 }
593 spin_unlock(lock: &ioapic->lock);
594}
595
596static inline struct kvm_ioapic *to_ioapic(struct kvm_io_device *dev)
597{
598 return container_of(dev, struct kvm_ioapic, dev);
599}
600
601static inline int ioapic_in_range(struct kvm_ioapic *ioapic, gpa_t addr)
602{
603 return ((addr >= ioapic->base_address &&
604 (addr < ioapic->base_address + IOAPIC_MEM_LENGTH)));
605}
606
607static int ioapic_mmio_read(struct kvm_vcpu *vcpu, struct kvm_io_device *this,
608 gpa_t addr, int len, void *val)
609{
610 struct kvm_ioapic *ioapic = to_ioapic(dev: this);
611 u32 result;
612 if (!ioapic_in_range(ioapic, addr))
613 return -EOPNOTSUPP;
614
615 ASSERT(!(addr & 0xf)); /* check alignment */
616
617 addr &= 0xff;
618 spin_lock(lock: &ioapic->lock);
619 switch (addr) {
620 case IOAPIC_REG_SELECT:
621 result = ioapic->ioregsel;
622 break;
623
624 case IOAPIC_REG_WINDOW:
625 result = ioapic_read_indirect(ioapic);
626 break;
627
628 default:
629 result = 0;
630 break;
631 }
632 spin_unlock(lock: &ioapic->lock);
633
634 switch (len) {
635 case 8:
636 *(u64 *) val = result;
637 break;
638 case 1:
639 case 2:
640 case 4:
641 memcpy(val, (char *)&result, len);
642 break;
643 default:
644 printk(KERN_WARNING "ioapic: wrong length %d\n", len);
645 }
646 return 0;
647}
648
649static int ioapic_mmio_write(struct kvm_vcpu *vcpu, struct kvm_io_device *this,
650 gpa_t addr, int len, const void *val)
651{
652 struct kvm_ioapic *ioapic = to_ioapic(dev: this);
653 u32 data;
654 if (!ioapic_in_range(ioapic, addr))
655 return -EOPNOTSUPP;
656
657 ASSERT(!(addr & 0xf)); /* check alignment */
658
659 switch (len) {
660 case 8:
661 case 4:
662 data = *(u32 *) val;
663 break;
664 case 2:
665 data = *(u16 *) val;
666 break;
667 case 1:
668 data = *(u8 *) val;
669 break;
670 default:
671 printk(KERN_WARNING "ioapic: Unsupported size %d\n", len);
672 return 0;
673 }
674
675 addr &= 0xff;
676 spin_lock(lock: &ioapic->lock);
677 switch (addr) {
678 case IOAPIC_REG_SELECT:
679 ioapic->ioregsel = data & 0xFF; /* 8-bit register */
680 break;
681
682 case IOAPIC_REG_WINDOW:
683 ioapic_write_indirect(ioapic, val: data);
684 break;
685
686 default:
687 break;
688 }
689 spin_unlock(lock: &ioapic->lock);
690 return 0;
691}
692
693static void kvm_ioapic_reset(struct kvm_ioapic *ioapic)
694{
695 int i;
696
697 cancel_delayed_work_sync(dwork: &ioapic->eoi_inject);
698 for (i = 0; i < IOAPIC_NUM_PINS; i++)
699 ioapic->redirtbl[i].fields.mask = 1;
700 ioapic->base_address = IOAPIC_DEFAULT_BASE_ADDRESS;
701 ioapic->ioregsel = 0;
702 ioapic->irr = 0;
703 ioapic->irr_delivered = 0;
704 ioapic->id = 0;
705 memset(ioapic->irq_eoi, 0x00, sizeof(ioapic->irq_eoi));
706 rtc_irq_eoi_tracking_reset(ioapic);
707}
708
709static const struct kvm_io_device_ops ioapic_mmio_ops = {
710 .read = ioapic_mmio_read,
711 .write = ioapic_mmio_write,
712};
713
714int kvm_ioapic_init(struct kvm *kvm)
715{
716 struct kvm_ioapic *ioapic;
717 int ret;
718
719 ioapic = kzalloc(size: sizeof(struct kvm_ioapic), GFP_KERNEL_ACCOUNT);
720 if (!ioapic)
721 return -ENOMEM;
722 spin_lock_init(&ioapic->lock);
723 INIT_DELAYED_WORK(&ioapic->eoi_inject, kvm_ioapic_eoi_inject_work);
724 kvm->arch.vioapic = ioapic;
725 kvm_ioapic_reset(ioapic);
726 kvm_iodevice_init(dev: &ioapic->dev, ops: &ioapic_mmio_ops);
727 ioapic->kvm = kvm;
728 mutex_lock(&kvm->slots_lock);
729 ret = kvm_io_bus_register_dev(kvm, bus_idx: KVM_MMIO_BUS, addr: ioapic->base_address,
730 IOAPIC_MEM_LENGTH, dev: &ioapic->dev);
731 mutex_unlock(lock: &kvm->slots_lock);
732 if (ret < 0) {
733 kvm->arch.vioapic = NULL;
734 kfree(objp: ioapic);
735 }
736
737 return ret;
738}
739
740void kvm_ioapic_destroy(struct kvm *kvm)
741{
742 struct kvm_ioapic *ioapic = kvm->arch.vioapic;
743
744 if (!ioapic)
745 return;
746
747 cancel_delayed_work_sync(dwork: &ioapic->eoi_inject);
748 mutex_lock(&kvm->slots_lock);
749 kvm_io_bus_unregister_dev(kvm, bus_idx: KVM_MMIO_BUS, dev: &ioapic->dev);
750 mutex_unlock(lock: &kvm->slots_lock);
751 kvm->arch.vioapic = NULL;
752 kfree(objp: ioapic);
753}
754
755void kvm_get_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state)
756{
757 struct kvm_ioapic *ioapic = kvm->arch.vioapic;
758
759 spin_lock(lock: &ioapic->lock);
760 memcpy(state, ioapic, sizeof(struct kvm_ioapic_state));
761 state->irr &= ~ioapic->irr_delivered;
762 spin_unlock(lock: &ioapic->lock);
763}
764
765void kvm_set_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state)
766{
767 struct kvm_ioapic *ioapic = kvm->arch.vioapic;
768
769 spin_lock(lock: &ioapic->lock);
770 memcpy(ioapic, state, sizeof(struct kvm_ioapic_state));
771 ioapic->irr = 0;
772 ioapic->irr_delivered = 0;
773 kvm_make_scan_ioapic_request(kvm);
774 kvm_ioapic_inject_all(ioapic, irr: state->irr);
775 spin_unlock(lock: &ioapic->lock);
776}
777

source code of linux/arch/x86/kvm/ioapic.c