arch/x86/kvm/ioapic.c

   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 && old_irr == ioapic->irr) ||
 210             (!edge && entry.fields.remote_irr)) {
 211                 ret = 0;
 212                 goto out;
 213         }
 214
 215         ret = ioapic_service(ioapic, irq, line_status);
 216
 217 out:
 218         trace_kvm_ioapic_set_irq(entry.bits, irq, ret == 0);
 219         return ret;
 220 }
 221
 222 static void kvm_ioapic_inject_all(struct kvm_ioapic *ioapic, unsigned long irr)
 223 {
 224         u32 idx;
 225
 226         rtc_irq_eoi_tracking_reset(ioapic);
 227         for_each_set_bit(idx, &irr, IOAPIC_NUM_PINS)
 228                 ioapic_set_irq(ioapic, idx, 1, true);
 229
 230         kvm_rtc_eoi_tracking_restore_all(ioapic);
 231 }
 232
 233
 234 static void update_handled_vectors(struct kvm_ioapic *ioapic)
 235 {
 236         DECLARE_BITMAP(handled_vectors, 256);
 237         int i;
 238
 239         memset(handled_vectors, 0, sizeof(handled_vectors));
 240         for (i = 0; i < IOAPIC_NUM_PINS; ++i)
 241                 __set_bit(ioapic->redirtbl[i].fields.vector, handled_vectors);
 242         memcpy(ioapic->handled_vectors, handled_vectors,
 243                sizeof(handled_vectors));
 244         smp_wmb();
 245 }
 246
 247 void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap,
 248                         u32 *tmr)
 249 {
 250         struct kvm_ioapic *ioapic = vcpu->kvm->arch.vioapic;
 251         union kvm_ioapic_redirect_entry *e;
 252         int index;
 253
 254         spin_lock(&ioapic->lock);
 255         for (index = 0; index < IOAPIC_NUM_PINS; index++) {
 256                 e = &ioapic->redirtbl[index];
 257                 if (e->fields.trig_mode == IOAPIC_LEVEL_TRIG ||
 258                     kvm_irq_has_notifier(ioapic->kvm, KVM_IRQCHIP_IOAPIC, index) ||
 259                     index == RTC_GSI) {
 260                         if (kvm_apic_match_dest(vcpu, NULL, 0,
 261                                 e->fields.dest_id, e->fields.dest_mode)) {
 262                                 __set_bit(e->fields.vector,
 263                                         (unsigned long *)eoi_exit_bitmap);
 264                                 if (e->fields.trig_mode == IOAPIC_LEVEL_TRIG)
 265                                         __set_bit(e->fields.vector,
 266                                                 (unsigned long *)tmr);
 267                         }
 268                 }
 269         }
 270         spin_unlock(&ioapic->lock);
 271 }
 272
 273 void kvm_vcpu_request_scan_ioapic(struct kvm *kvm)
 274 {
 275         struct kvm_ioapic *ioapic = kvm->arch.vioapic;
 276
 277         if (!ioapic)
 278                 return;
 279         kvm_make_scan_ioapic_request(kvm);
 280 }
 281
 282 static void ioapic_write_indirect(struct kvm_ioapic *ioapic, u32 val)
 283 {
 284         unsigned index;
 285         bool mask_before, mask_after;
 286         union kvm_ioapic_redirect_entry *e;
 287
 288         switch (ioapic->ioregsel) {
 289         case IOAPIC_REG_VERSION:
 290                 /* Writes are ignored. */
 291                 break;
 292
 293         case IOAPIC_REG_APIC_ID:
 294                 ioapic->id = (val >> 24) & 0xf;
 295                 break;
 296
 297         case IOAPIC_REG_ARB_ID:
 298                 break;
 299
 300         default:
 301                 index = (ioapic->ioregsel - 0x10) >> 1;
 302
 303                 ioapic_debug("change redir index %x val %x\n", index, val);
 304                 if (index >= IOAPIC_NUM_PINS)
 305                         return;
 306                 e = &ioapic->redirtbl[index];
 307                 mask_before = e->fields.mask;
 308                 if (ioapic->ioregsel & 1) {
 309                         e->bits &= 0xffffffff;
 310                         e->bits |= (u64) val << 32;
 311                 } else {
 312                         e->bits &= ~0xffffffffULL;
 313                         e->bits |= (u32) val;
 314                         e->fields.remote_irr = 0;
 315                 }
 316                 update_handled_vectors(ioapic);
 317                 mask_after = e->fields.mask;
 318                 if (mask_before != mask_after)
 319                         kvm_fire_mask_notifiers(ioapic->kvm, KVM_IRQCHIP_IOAPIC, index, mask_after);
 320                 if (e->fields.trig_mode == IOAPIC_LEVEL_TRIG
 321                     && ioapic->irr & (1 << index))
 322                         ioapic_service(ioapic, index, false);
 323                 kvm_vcpu_request_scan_ioapic(ioapic->kvm);
 324                 break;
 325         }
 326 }
 327
 328 static int ioapic_service(struct kvm_ioapic *ioapic, int irq, bool line_status)
 329 {
 330         union kvm_ioapic_redirect_entry *entry = &ioapic->redirtbl[irq];
 331         struct kvm_lapic_irq irqe;
 332         int ret;
 333
 334         if (entry->fields.mask)
 335                 return -1;
 336
 337         ioapic_debug("dest=%x dest_mode=%x delivery_mode=%x "
 338                      "vector=%x trig_mode=%x\n",
 339                      entry->fields.dest_id, entry->fields.dest_mode,
 340                      entry->fields.delivery_mode, entry->fields.vector,
 341                      entry->fields.trig_mode);
 342
 343         irqe.dest_id = entry->fields.dest_id;
 344         irqe.vector = entry->fields.vector;
 345         irqe.dest_mode = entry->fields.dest_mode;
 346         irqe.trig_mode = entry->fields.trig_mode;
 347         irqe.delivery_mode = entry->fields.delivery_mode << 8;
 348         irqe.level = 1;
 349         irqe.shorthand = 0;
 350
 351         if (irqe.trig_mode == IOAPIC_EDGE_TRIG)
 352                 ioapic->irr &= ~(1 << irq);
 353
 354         if (irq == RTC_GSI && line_status) {
 355                 /*
 356                  * pending_eoi cannot ever become negative (see
 357                  * rtc_status_pending_eoi_check_valid) and the caller
 358                  * ensures that it is only called if it is >= zero, namely
 359                  * if rtc_irq_check_coalesced returns false).
 360                  */
 361                 BUG_ON(ioapic->rtc_status.pending_eoi != 0);
 362                 ret = kvm_irq_delivery_to_apic(ioapic->kvm, NULL, &irqe,
 363                                 ioapic->rtc_status.dest_map);
 364                 ioapic->rtc_status.pending_eoi = (ret < 0 ? 0 : ret);
 365         } else
 366                 ret = kvm_irq_delivery_to_apic(ioapic->kvm, NULL, &irqe, NULL);
 367
 368         if (ret && irqe.trig_mode == IOAPIC_LEVEL_TRIG)
 369                 entry->fields.remote_irr = 1;
 370
 371         return ret;
 372 }
 373
 374 int kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int irq_source_id,
 375                        int level, bool line_status)
 376 {
 377         int ret, irq_level;
 378
 379         BUG_ON(irq < 0 || irq >= IOAPIC_NUM_PINS);
 380
 381         spin_lock(&ioapic->lock);
 382         irq_level = __kvm_irq_line_state(&ioapic->irq_states[irq],
 383                                          irq_source_id, level);
 384         ret = ioapic_set_irq(ioapic, irq, irq_level, line_status);
 385
 386         spin_unlock(&ioapic->lock);
 387
 388         return ret;
 389 }
 390
 391 void kvm_ioapic_clear_all(struct kvm_ioapic *ioapic, int irq_source_id)
 392 {
 393         int i;
 394
 395         spin_lock(&ioapic->lock);
 396         for (i = 0; i < KVM_IOAPIC_NUM_PINS; i++)
 397                 __clear_bit(irq_source_id, &ioapic->irq_states[i]);
 398         spin_unlock(&ioapic->lock);
 399 }
 400
 401 static void kvm_ioapic_eoi_inject_work(struct work_struct *work)
 402 {
 403         int i;
 404         struct kvm_ioapic *ioapic = container_of(work, struct kvm_ioapic,
 405                                                  eoi_inject.work);
 406         spin_lock(&ioapic->lock);
 407         for (i = 0; i < IOAPIC_NUM_PINS; i++) {
 408                 union kvm_ioapic_redirect_entry *ent = &ioapic->redirtbl[i];
 409
 410                 if (ent->fields.trig_mode != IOAPIC_LEVEL_TRIG)
 411                         continue;
 412
 413                 if (ioapic->irr & (1 << i) && !ent->fields.remote_irr)
 414                         ioapic_service(ioapic, i, false);
 415         }
 416         spin_unlock(&ioapic->lock);
 417 }
 418
 419 #define IOAPIC_SUCCESSIVE_IRQ_MAX_COUNT 10000
 420
 421 static void __kvm_ioapic_update_eoi(struct kvm_vcpu *vcpu,
 422                         struct kvm_ioapic *ioapic, int vector, int trigger_mode)
 423 {
 424         int i;
 425
 426         for (i = 0; i < IOAPIC_NUM_PINS; i++) {
 427                 union kvm_ioapic_redirect_entry *ent = &ioapic->redirtbl[i];
 428
 429                 if (ent->fields.vector != vector)
 430                         continue;
 431
 432                 if (i == RTC_GSI)
 433                         rtc_irq_eoi(ioapic, vcpu);
 434                 /*
 435                  * We are dropping lock while calling ack notifiers because ack
 436                  * notifier callbacks for assigned devices call into IOAPIC
 437                  * recursively. Since remote_irr is cleared only after call
 438                  * to notifiers if the same vector will be delivered while lock
 439                  * is dropped it will be put into irr and will be delivered
 440                  * after ack notifier returns.
 441                  */
 442                 spin_unlock(&ioapic->lock);
 443                 kvm_notify_acked_irq(ioapic->kvm, KVM_IRQCHIP_IOAPIC, i);
 444                 spin_lock(&ioapic->lock);
 445
 446                 if (trigger_mode != IOAPIC_LEVEL_TRIG)
 447                         continue;
 448
 449                 ASSERT(ent->fields.trig_mode == IOAPIC_LEVEL_TRIG);
 450                 ent->fields.remote_irr = 0;
 451                 if (!ent->fields.mask && (ioapic->irr & (1 << i))) {
 452                         ++ioapic->irq_eoi[i];
 453                         if (ioapic->irq_eoi[i] == IOAPIC_SUCCESSIVE_IRQ_MAX_COUNT) {
 454                                 /*
 455                                  * Real hardware does not deliver the interrupt
 456                                  * immediately during eoi broadcast, and this
 457                                  * lets a buggy guest make slow progress
 458                                  * even if it does not correctly handle a
 459                                  * level-triggered interrupt.  Emulate this
 460                                  * behavior if we detect an interrupt storm.
 461                                  */
 462                                 schedule_delayed_work(&ioapic->eoi_inject, HZ / 100);
 463                                 ioapic->irq_eoi[i] = 0;
 464                                 trace_kvm_ioapic_delayed_eoi_inj(ent->bits);
 465                         } else {
 466                                 ioapic_service(ioapic, i, false);
 467                         }
 468                 } else {
 469                         ioapic->irq_eoi[i] = 0;
 470                 }
 471         }
 472 }
 473
 474 bool kvm_ioapic_handles_vector(struct kvm *kvm, int vector)
 475 {
 476         struct kvm_ioapic *ioapic = kvm->arch.vioapic;
 477         smp_rmb();
 478         return test_bit(vector, ioapic->handled_vectors);
 479 }
 480
 481 void kvm_ioapic_update_eoi(struct kvm_vcpu *vcpu, int vector, int trigger_mode)
 482 {
 483         struct kvm_ioapic *ioapic = vcpu->kvm->arch.vioapic;
 484
 485         spin_lock(&ioapic->lock);
 486         __kvm_ioapic_update_eoi(vcpu, ioapic, vector, trigger_mode);
 487         spin_unlock(&ioapic->lock);
 488 }
 489
 490 static inline struct kvm_ioapic *to_ioapic(struct kvm_io_device *dev)
 491 {
 492         return container_of(dev, struct kvm_ioapic, dev);
 493 }
 494
 495 static inline int ioapic_in_range(struct kvm_ioapic *ioapic, gpa_t addr)
 496 {
 497         return ((addr >= ioapic->base_address &&
 498                  (addr < ioapic->base_address + IOAPIC_MEM_LENGTH)));
 499 }
 500
 501 static int ioapic_mmio_read(struct kvm_io_device *this, gpa_t addr, int len,
 502                             void *val)
 503 {
 504         struct kvm_ioapic *ioapic = to_ioapic(this);
 505         u32 result;
 506         if (!ioapic_in_range(ioapic, addr))
 507                 return -EOPNOTSUPP;
 508
 509         ioapic_debug("addr %lx\n", (unsigned long)addr);
 510         ASSERT(!(addr & 0xf));  /* check alignment */
 511
 512         addr &= 0xff;
 513         spin_lock(&ioapic->lock);
 514         switch (addr) {
 515         case IOAPIC_REG_SELECT:
 516                 result = ioapic->ioregsel;
 517                 break;
 518
 519         case IOAPIC_REG_WINDOW:
 520                 result = ioapic_read_indirect(ioapic, addr, len);
 521                 break;
 522
 523         default:
 524                 result = 0;
 525                 break;
 526         }
 527         spin_unlock(&ioapic->lock);
 528
 529         switch (len) {
 530         case 8:
 531                 *(u64 *) val = result;
 532                 break;
 533         case 1:
 534         case 2:
 535         case 4:
 536                 memcpy(val, (char *)&result, len);
 537                 break;
 538         default:
 539                 printk(KERN_WARNING "ioapic: wrong length %d\n", len);
 540         }
 541         return 0;
 542 }
 543
 544 static int ioapic_mmio_write(struct kvm_io_device *this, gpa_t addr, int len,
 545                              const void *val)
 546 {
 547         struct kvm_ioapic *ioapic = to_ioapic(this);
 548         u32 data;
 549         if (!ioapic_in_range(ioapic, addr))
 550                 return -EOPNOTSUPP;
 551
 552         ioapic_debug("ioapic_mmio_write addr=%p len=%d val=%p\n",
 553                      (void*)addr, len, val);
 554         ASSERT(!(addr & 0xf));  /* check alignment */
 555
 556         switch (len) {
 557         case 8:
 558         case 4:
 559                 data = *(u32 *) val;
 560                 break;
 561         case 2:
 562                 data = *(u16 *) val;
 563                 break;
 564         case 1:
 565                 data = *(u8  *) val;
 566                 break;
 567         default:
 568                 printk(KERN_WARNING "ioapic: Unsupported size %d\n", len);
 569                 return 0;
 570         }
 571
 572         addr &= 0xff;
 573         spin_lock(&ioapic->lock);
 574         switch (addr) {
 575         case IOAPIC_REG_SELECT:
 576                 ioapic->ioregsel = data & 0xFF; /* 8-bit register */
 577                 break;
 578
 579         case IOAPIC_REG_WINDOW:
 580                 ioapic_write_indirect(ioapic, data);
 581                 break;
 582
 583         default:
 584                 break;
 585         }
 586         spin_unlock(&ioapic->lock);
 587         return 0;
 588 }
 589
 590 static void kvm_ioapic_reset(struct kvm_ioapic *ioapic)
 591 {
 592         int i;
 593
 594         cancel_delayed_work_sync(&ioapic->eoi_inject);
 595         for (i = 0; i < IOAPIC_NUM_PINS; i++)
 596                 ioapic->redirtbl[i].fields.mask = 1;
 597         ioapic->base_address = IOAPIC_DEFAULT_BASE_ADDRESS;
 598         ioapic->ioregsel = 0;
 599         ioapic->irr = 0;
 600         ioapic->id = 0;
 601         memset(ioapic->irq_eoi, 0x00, IOAPIC_NUM_PINS);
 602         rtc_irq_eoi_tracking_reset(ioapic);
 603         update_handled_vectors(ioapic);
 604 }
 605
 606 static const struct kvm_io_device_ops ioapic_mmio_ops = {
 607         .read     = ioapic_mmio_read,
 608         .write    = ioapic_mmio_write,
 609 };
 610
 611 int kvm_ioapic_init(struct kvm *kvm)
 612 {
 613         struct kvm_ioapic *ioapic;
 614         int ret;
 615
 616         ioapic = kzalloc(sizeof(struct kvm_ioapic), GFP_KERNEL);
 617         if (!ioapic)
 618                 return -ENOMEM;
 619         spin_lock_init(&ioapic->lock);
 620         INIT_DELAYED_WORK(&ioapic->eoi_inject, kvm_ioapic_eoi_inject_work);
 621         kvm->arch.vioapic = ioapic;
 622         kvm_ioapic_reset(ioapic);
 623         kvm_iodevice_init(&ioapic->dev, &ioapic_mmio_ops);
 624         ioapic->kvm = kvm;
 625         mutex_lock(&kvm->slots_lock);
 626         ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, ioapic->base_address,
 627                                       IOAPIC_MEM_LENGTH, &ioapic->dev);
 628         mutex_unlock(&kvm->slots_lock);
 629         if (ret < 0) {
 630                 kvm->arch.vioapic = NULL;
 631                 kfree(ioapic);
 632         }
 633
 634         return ret;
 635 }
 636
 637 void kvm_ioapic_destroy(struct kvm *kvm)
 638 {
 639         struct kvm_ioapic *ioapic = kvm->arch.vioapic;
 640
 641         cancel_delayed_work_sync(&ioapic->eoi_inject);
 642         if (ioapic) {
 643                 kvm_io_bus_unregister_dev(kvm, KVM_MMIO_BUS, &ioapic->dev);
 644                 kvm->arch.vioapic = NULL;
 645                 kfree(ioapic);
 646         }
 647 }
 648
 649 int kvm_get_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state)
 650 {
 651         struct kvm_ioapic *ioapic = ioapic_irqchip(kvm);
 652         if (!ioapic)
 653                 return -EINVAL;
 654
 655         spin_lock(&ioapic->lock);
 656         memcpy(state, ioapic, sizeof(struct kvm_ioapic_state));
 657         spin_unlock(&ioapic->lock);
 658         return 0;
 659 }
 660
 661 int kvm_set_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state)
 662 {
 663         struct kvm_ioapic *ioapic = ioapic_irqchip(kvm);
 664         if (!ioapic)
 665                 return -EINVAL;
 666
 667         spin_lock(&ioapic->lock);
 668         memcpy(ioapic, state, sizeof(struct kvm_ioapic_state));
 669         ioapic->irr = 0;
 670         update_handled_vectors(ioapic);
 671         kvm_vcpu_request_scan_ioapic(kvm);
 672         kvm_ioapic_inject_all(ioapic, state->irr);
 673         spin_unlock(&ioapic->lock);
 674         return 0;
 675 }