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)
 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_io_device *this, gpa_t addr, int len,
 497                             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_io_device *this, gpa_t addr, int len,
 540                              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 }