qemu-kvm.c

   1
   2 #include "config.h"
   3 #include "config-host.h"
   4
   5 #ifdef USE_KVM
   6  #define KVM_ALLOWED_DEFAULT 1
   7 #else
   8  #define KVM_ALLOWED_DEFAULT 0
   9 #endif
  10
  11 int kvm_allowed = KVM_ALLOWED_DEFAULT;
  12 int kvm_irqchip = 1;
  13
  14 #ifdef USE_KVM
  15
  16 #include <string.h>
  17 #include "hw/hw.h"
  18 #include "sysemu.h"
  19
  20 #include "qemu-kvm.h"
  21 #include <libkvm.h>
  22 #include <pthread.h>
  23 #include <sys/utsname.h>
  24
  25 extern void perror(const char *s);
  26
  27 kvm_context_t kvm_context;
  28
  29 extern int smp_cpus;
  30
  31 pthread_mutex_t qemu_mutex = PTHREAD_MUTEX_INITIALIZER;
  32 __thread CPUState *vcpu_env;
  33
  34 static sigset_t io_sigset, io_negsigset;
  35
  36 static int wait_hack;
  37
  38 #define SIG_IPI (SIGRTMIN+4)
  39
  40 struct vcpu_info {
  41     int sipi_needed;
  42     int init;
  43     pthread_t thread;
  44     int signalled;
  45     int stop;
  46     int stopped;
  47 } vcpu_info[4];
  48
  49 static void sig_ipi_handler(int n)
  50 {
  51 }
  52
  53 void kvm_update_interrupt_request(CPUState *env)
  54 {
  55     if (env && env != vcpu_env) {
  56         if (vcpu_info[env->cpu_index].signalled)
  57             return;
  58         vcpu_info[env->cpu_index].signalled = 1;
  59         if (vcpu_info[env->cpu_index].thread)
  60             pthread_kill(vcpu_info[env->cpu_index].thread, SIG_IPI);
  61     }
  62 }
  63
  64 void kvm_update_after_sipi(CPUState *env)
  65 {
  66     vcpu_info[env->cpu_index].sipi_needed = 1;
  67     kvm_update_interrupt_request(env);
  68
  69     /*
  70      * the qemu bios waits using a busy loop that's much too short for
  71      * kvm.  add a wait after the first sipi.
  72      */
  73     {
  74         static int first_sipi = 1;
  75
  76         if (first_sipi) {
  77             wait_hack = 1;
  78             first_sipi = 0;
  79         }
  80     }
  81 }
  82
  83 void kvm_apic_init(CPUState *env)
  84 {
  85     if (env->cpu_index != 0)
  86         vcpu_info[env->cpu_index].init = 1;
  87     kvm_update_interrupt_request(env);
  88 }
  89
  90 #include <signal.h>
  91
  92 static int try_push_interrupts(void *opaque)
  93 {
  94     return kvm_arch_try_push_interrupts(opaque);
  95 }
  96
  97 static void post_kvm_run(void *opaque, int vcpu)
  98 {
  99
 100     pthread_mutex_lock(&qemu_mutex);
 101     kvm_arch_post_kvm_run(opaque, vcpu);
 102 }
 103
 104 static int pre_kvm_run(void *opaque, int vcpu)
 105 {
 106     CPUState *env = cpu_single_env;
 107
 108     if (env->cpu_index == 0 && wait_hack) {
 109         int i;
 110
 111         wait_hack = 0;
 112
 113         pthread_mutex_unlock(&qemu_mutex);
 114         for (i = 0; i < 10; ++i)
 115             usleep(1000);
 116         pthread_mutex_lock(&qemu_mutex);
 117     }
 118
 119     kvm_arch_pre_kvm_run(opaque, vcpu);
 120
 121     if (env->interrupt_request & CPU_INTERRUPT_EXIT)
 122         return 1;
 123     pthread_mutex_unlock(&qemu_mutex);
 124     return 0;
 125 }
 126
 127 void kvm_load_registers(CPUState *env)
 128 {
 129     if (kvm_allowed)
 130         kvm_arch_load_regs(env);
 131 }
 132
 133 void kvm_save_registers(CPUState *env)
 134 {
 135     if (kvm_allowed)
 136         kvm_arch_save_regs(env);
 137 }
 138
 139 int kvm_cpu_exec(CPUState *env)
 140 {
 141     int r;
 142
 143     r = kvm_run(kvm_context, env->cpu_index);
 144     if (r < 0) {
 145         printf("kvm_run returned %d\n", r);
 146         exit(1);
 147     }
 148
 149     return 0;
 150 }
 151
 152 extern int vm_running;
 153
 154 static int has_work(CPUState *env)
 155 {
 156     if (!vm_running)
 157         return 0;
 158     if (!(env->hflags & HF_HALTED_MASK))
 159         return 1;
 160     return kvm_arch_has_work(env);
 161 }
 162
 163 static int kvm_eat_signal(CPUState *env, int timeout)
 164 {
 165     struct timespec ts;
 166     int r, e, ret = 0;
 167     siginfo_t siginfo;
 168     struct sigaction sa;
 169
 170     ts.tv_sec = timeout / 1000;
 171     ts.tv_nsec = (timeout % 1000) * 1000000;
 172     r = sigtimedwait(&io_sigset, &siginfo, &ts);
 173     if (r == -1 && (errno == EAGAIN || errno == EINTR) && !timeout)
 174         return 0;
 175     e = errno;
 176     pthread_mutex_lock(&qemu_mutex);
 177     cpu_single_env = vcpu_env;
 178     if (r == -1 && !(errno == EAGAIN || errno == EINTR)) {
 179         printf("sigtimedwait: %s\n", strerror(e));
 180         exit(1);
 181     }
 182     if (r != -1) {
 183         sigaction(siginfo.si_signo, NULL, &sa);
 184         sa.sa_handler(siginfo.si_signo);
 185         ret = 1;
 186     }
 187     pthread_mutex_unlock(&qemu_mutex);
 188
 189     return ret;
 190 }
 191
 192
 193 static void kvm_eat_signals(CPUState *env, int timeout)
 194 {
 195     int r = 0;
 196
 197     while (kvm_eat_signal(env, 0))
 198         r = 1;
 199     if (!r && timeout) {
 200         r = kvm_eat_signal(env, timeout);
 201         if (r)
 202             while (kvm_eat_signal(env, 0))
 203                 ;
 204     }
 205     /*
 206      * we call select() even if no signal was received, to account for
 207      * for which there is no signal handler installed.
 208      */
 209     pthread_mutex_lock(&qemu_mutex);
 210     cpu_single_env = vcpu_env;
 211     main_loop_wait(0);
 212     pthread_mutex_unlock(&qemu_mutex);
 213 }
 214
 215 static void kvm_main_loop_wait(CPUState *env, int timeout)
 216 {
 217     pthread_mutex_unlock(&qemu_mutex);
 218     if (env->cpu_index == 0)
 219         kvm_eat_signals(env, timeout);
 220     else {
 221         if (!kvm_irqchip_in_kernel(kvm_context) &&
 222             (timeout || vcpu_info[env->cpu_index].stopped)) {
 223             sigset_t set;
 224             int n;
 225
 226         paused:
 227             sigemptyset(&set);
 228             sigaddset(&set, SIG_IPI);
 229             sigwait(&set, &n);
 230         } else {
 231             struct timespec ts;
 232             siginfo_t siginfo;
 233             sigset_t set;
 234
 235             ts.tv_sec = 0;
 236             ts.tv_nsec = 0;
 237             sigemptyset(&set);
 238             sigaddset(&set, SIG_IPI);
 239             sigtimedwait(&set, &siginfo, &ts);
 240         }
 241         if (vcpu_info[env->cpu_index].stop) {
 242             vcpu_info[env->cpu_index].stop = 0;
 243             vcpu_info[env->cpu_index].stopped = 1;
 244             pthread_kill(vcpu_info[0].thread, SIG_IPI);
 245             goto paused;
 246         }
 247     }
 248     pthread_mutex_lock(&qemu_mutex);
 249     cpu_single_env = env;
 250     vcpu_info[env->cpu_index].signalled = 0;
 251 }
 252
 253 static int all_threads_paused(void)
 254 {
 255     int i;
 256
 257     for (i = 1; i < smp_cpus; ++i)
 258         if (vcpu_info[i].stopped)
 259             return 0;
 260     return 1;
 261 }
 262
 263 static void pause_other_threads(void)
 264 {
 265     int i;
 266
 267     for (i = 1; i < smp_cpus; ++i) {
 268         vcpu_info[i].stop = 1;
 269         pthread_kill(vcpu_info[i].thread, SIG_IPI);
 270     }
 271     while (!all_threads_paused())
 272         kvm_eat_signals(vcpu_env, 0);
 273 }
 274
 275 static void resume_other_threads(void)
 276 {
 277     int i;
 278
 279     for (i = 1; i < smp_cpus; ++i) {
 280         vcpu_info[i].stop = 0;
 281         vcpu_info[i].stopped = 0;
 282         pthread_kill(vcpu_info[i].thread, SIG_IPI);
 283     }
 284 }
 285
 286 static void kvm_vm_state_change_handler(void *context, int running)
 287 {
 288     if (running)
 289         resume_other_threads();
 290     else
 291         pause_other_threads();
 292 }
 293
 294 static void update_regs_for_sipi(CPUState *env)
 295 {
 296     kvm_arch_update_regs_for_sipi(env);
 297     vcpu_info[env->cpu_index].sipi_needed = 0;
 298     vcpu_info[env->cpu_index].init = 0;
 299 }
 300
 301 static void update_regs_for_init(CPUState *env)
 302 {
 303     cpu_reset(env);
 304     kvm_arch_load_regs(env);
 305 }
 306
 307 static void setup_kernel_sigmask(CPUState *env)
 308 {
 309     sigset_t set;
 310
 311     sigprocmask(SIG_BLOCK, NULL, &set);
 312     sigdelset(&set, SIG_IPI);
 313     if (env->cpu_index == 0)
 314         sigandset(&set, &set, &io_negsigset);
 315
 316     kvm_set_signal_mask(kvm_context, env->cpu_index, &set);
 317 }
 318
 319 static int kvm_main_loop_cpu(CPUState *env)
 320 {
 321     struct vcpu_info *info = &vcpu_info[env->cpu_index];
 322
 323     setup_kernel_sigmask(env);
 324     pthread_mutex_lock(&qemu_mutex);
 325
 326     kvm_qemu_init_env(env);
 327     env->ready_for_interrupt_injection = 1;
 328
 329     cpu_single_env = env;
 330 #ifdef TARGET_I386
 331     kvm_tpr_opt_setup(env);
 332 #endif
 333     while (1) {
 334         while (!has_work(env))
 335             kvm_main_loop_wait(env, 10);
 336         if (env->interrupt_request & CPU_INTERRUPT_HARD)
 337             env->hflags &= ~HF_HALTED_MASK;
 338         if (!kvm_irqchip_in_kernel(kvm_context) && info->sipi_needed)
 339             update_regs_for_sipi(env);
 340         if (!kvm_irqchip_in_kernel(kvm_context) && info->init)
 341             update_regs_for_init(env);
 342         if (!(env->hflags & HF_HALTED_MASK) && !info->init)
 343             kvm_cpu_exec(env);
 344         env->interrupt_request &= ~CPU_INTERRUPT_EXIT;
 345         kvm_main_loop_wait(env, 0);
 346         if (qemu_shutdown_requested())
 347             break;
 348         else if (qemu_powerdown_requested())
 349             qemu_system_powerdown();
 350         else if (qemu_reset_requested()) {
 351             env->interrupt_request = 0;
 352             qemu_system_reset();
 353             kvm_arch_load_regs(env);
 354         }
 355     }
 356     pthread_mutex_unlock(&qemu_mutex);
 357     return 0;
 358 }
 359
 360 static void *ap_main_loop(void *_env)
 361 {
 362     CPUState *env = _env;
 363     sigset_t signals;
 364
 365     vcpu_env = env;
 366     sigfillset(&signals);
 367     //sigdelset(&signals, SIG_IPI);
 368     sigprocmask(SIG_BLOCK, &signals, NULL);
 369     kvm_create_vcpu(kvm_context, env->cpu_index);
 370     kvm_qemu_init_env(env);
 371     if (kvm_irqchip_in_kernel(kvm_context))
 372         env->hflags &= ~HF_HALTED_MASK;
 373     kvm_main_loop_cpu(env);
 374     return NULL;
 375 }
 376
 377 static void kvm_add_signal(int signum)
 378 {
 379     sigaddset(&io_sigset, signum);
 380     sigdelset(&io_negsigset, signum);
 381     sigprocmask(SIG_BLOCK,  &io_sigset, NULL);
 382 }
 383
 384 int kvm_init_ap(void)
 385 {
 386     CPUState *env = first_cpu->next_cpu;
 387     int i;
 388
 389     qemu_add_vm_change_state_handler(kvm_vm_state_change_handler, NULL);
 390     sigemptyset(&io_sigset);
 391     sigfillset(&io_negsigset);
 392     kvm_add_signal(SIGIO);
 393     kvm_add_signal(SIGALRM);
 394     kvm_add_signal(SIGUSR2);
 395     if (!kvm_irqchip_in_kernel(kvm_context))
 396         kvm_add_signal(SIG_IPI);
 397
 398     vcpu_env = first_cpu;
 399     signal(SIG_IPI, sig_ipi_handler);
 400     for (i = 1; i < smp_cpus; ++i) {
 401         pthread_create(&vcpu_info[i].thread, NULL, ap_main_loop, env);
 402         env = env->next_cpu;
 403     }
 404     return 0;
 405 }
 406
 407 int kvm_main_loop(void)
 408 {
 409     vcpu_info[0].thread = pthread_self();
 410     return kvm_main_loop_cpu(first_cpu);
 411 }
 412
 413 static int kvm_debug(void *opaque, int vcpu)
 414 {
 415     CPUState *env = cpu_single_env;
 416
 417     env->exception_index = EXCP_DEBUG;
 418     return 1;
 419 }
 420
 421 static int kvm_inb(void *opaque, uint16_t addr, uint8_t *data)
 422 {
 423     *data = cpu_inb(0, addr);
 424     return 0;
 425 }
 426
 427 static int kvm_inw(void *opaque, uint16_t addr, uint16_t *data)
 428 {
 429     *data = cpu_inw(0, addr);
 430     return 0;
 431 }
 432
 433 static int kvm_inl(void *opaque, uint16_t addr, uint32_t *data)
 434 {
 435     *data = cpu_inl(0, addr);
 436     return 0;
 437 }
 438
 439 #define PM_IO_BASE 0xb000
 440
 441 static int kvm_outb(void *opaque, uint16_t addr, uint8_t data)
 442 {
 443     if (addr == 0xb2) {
 444         switch (data) {
 445         case 0: {
 446             cpu_outb(0, 0xb3, 0);
 447             break;
 448         }
 449         case 0xf0: {
 450             unsigned x;
 451
 452             /* enable acpi */
 453             x = cpu_inw(0, PM_IO_BASE + 4);
 454             x &= ~1;
 455             cpu_outw(0, PM_IO_BASE + 4, x);
 456             break;
 457         }
 458         case 0xf1: {
 459             unsigned x;
 460
 461             /* enable acpi */
 462             x = cpu_inw(0, PM_IO_BASE + 4);
 463             x |= 1;
 464             cpu_outw(0, PM_IO_BASE + 4, x);
 465             break;
 466         }
 467         default:
 468             break;
 469         }
 470         return 0;
 471     }
 472     cpu_outb(0, addr, data);
 473     return 0;
 474 }
 475
 476 static int kvm_outw(void *opaque, uint16_t addr, uint16_t data)
 477 {
 478     cpu_outw(0, addr, data);
 479     return 0;
 480 }
 481
 482 static int kvm_outl(void *opaque, uint16_t addr, uint32_t data)
 483 {
 484     cpu_outl(0, addr, data);
 485     return 0;
 486 }
 487
 488 static int kvm_mmio_read(void *opaque, uint64_t addr, uint8_t *data, int len)
 489 {
 490         cpu_physical_memory_rw(addr, data, len, 0);
 491         return 0;
 492 }
 493
 494 static int kvm_mmio_write(void *opaque, uint64_t addr, uint8_t *data, int len)
 495 {
 496         cpu_physical_memory_rw(addr, data, len, 1);
 497         return 0;
 498 }
 499
 500 static int kvm_io_window(void *opaque)
 501 {
 502     return 1;
 503 }
 504
 505
 506 static int kvm_halt(void *opaque, int vcpu)
 507 {
 508     return kvm_arch_halt(opaque, vcpu);
 509 }
 510
 511 static int kvm_shutdown(void *opaque, int vcpu)
 512 {
 513     qemu_system_reset_request();
 514     return 1;
 515 }
 516
 517 static struct kvm_callbacks qemu_kvm_ops = {
 518     .debug = kvm_debug,
 519     .inb   = kvm_inb,
 520     .inw   = kvm_inw,
 521     .inl   = kvm_inl,
 522     .outb  = kvm_outb,
 523     .outw  = kvm_outw,
 524     .outl  = kvm_outl,
 525     .mmio_read = kvm_mmio_read,
 526     .mmio_write = kvm_mmio_write,
 527     .halt  = kvm_halt,
 528     .shutdown = kvm_shutdown,
 529     .io_window = kvm_io_window,
 530     .try_push_interrupts = try_push_interrupts,
 531     .post_kvm_run = post_kvm_run,
 532     .pre_kvm_run = pre_kvm_run,
 533 #ifdef TARGET_I386
 534     .tpr_access = handle_tpr_access,
 535 #endif
 536 };
 537
 538 int kvm_qemu_init()
 539 {
 540     /* Try to initialize kvm */
 541     kvm_context = kvm_init(&qemu_kvm_ops, cpu_single_env);
 542     if (!kvm_context) {
 543         return -1;
 544     }
 545
 546     return 0;
 547 }
 548
 549 int kvm_qemu_create_context(void)
 550 {
 551     int r;
 552     if (!kvm_irqchip) {
 553         kvm_disable_irqchip_creation(kvm_context);
 554     }
 555     if (kvm_create(kvm_context, phys_ram_size, (void**)&phys_ram_base) < 0) {
 556         kvm_qemu_destroy();
 557         return -1;
 558     }
 559     r = kvm_arch_qemu_create_context();
 560     if(r <0)
 561         kvm_qemu_destroy();
 562     return 0;
 563 }
 564
 565 void kvm_qemu_destroy(void)
 566 {
 567     kvm_finalize(kvm_context);
 568 }
 569
 570 void kvm_cpu_register_physical_memory(target_phys_addr_t start_addr,
 571                                       unsigned long size,
 572                                       unsigned long phys_offset)
 573 {
 574 #ifdef KVM_CAP_USER_MEMORY
 575     int r = 0;
 576
 577     r = kvm_check_extension(kvm_context, KVM_CAP_USER_MEMORY);
 578     if (r) {
 579         if (!(phys_offset & ~TARGET_PAGE_MASK)) {
 580                 r = kvm_is_allocated_mem(kvm_context, start_addr, size);
 581             if (r)
 582                 return;
 583             r = kvm_is_intersecting_mem(kvm_context, start_addr);
 584             if (r)
 585                 kvm_create_mem_hole(kvm_context, start_addr, size);
 586             r = kvm_register_userspace_phys_mem(kvm_context, start_addr,
 587                                                 phys_ram_base + phys_offset,
 588                                                 size, 0);
 589         }
 590         if (phys_offset & IO_MEM_ROM) {
 591             phys_offset &= ~IO_MEM_ROM;
 592             r = kvm_is_intersecting_mem(kvm_context, start_addr);
 593             if (r)
 594                 kvm_create_mem_hole(kvm_context, start_addr, size);
 595             r = kvm_register_userspace_phys_mem(kvm_context, start_addr,
 596                                                 phys_ram_base + phys_offset,
 597                                                 size, 0);
 598         }
 599         if (r < 0) {
 600             printf("kvm_cpu_register_physical_memory: failed\n");
 601             exit(1);
 602         }
 603         return;
 604     }
 605 #endif
 606     if (phys_offset & IO_MEM_ROM) {
 607         phys_offset &= ~IO_MEM_ROM;
 608         memcpy(phys_ram_base + start_addr, phys_ram_base + phys_offset, size);
 609     }
 610 }
 611
 612 int kvm_qemu_check_extension(int ext)
 613 {
 614     return kvm_check_extension(kvm_context, ext);
 615 }
 616
 617 int kvm_qemu_init_env(CPUState *cenv)
 618 {
 619     return kvm_arch_qemu_init_env(cenv);
 620 }
 621
 622 int kvm_update_debugger(CPUState *env)
 623 {
 624     struct kvm_debug_guest dbg;
 625     int i;
 626
 627     dbg.enabled = 0;
 628     if (env->nb_breakpoints || env->singlestep_enabled) {
 629         dbg.enabled = 1;
 630         for (i = 0; i < 4 && i < env->nb_breakpoints; ++i) {
 631             dbg.breakpoints[i].enabled = 1;
 632             dbg.breakpoints[i].address = env->breakpoints[i];
 633         }
 634         dbg.singlestep = env->singlestep_enabled;
 635     }
 636     return kvm_guest_debug(kvm_context, env->cpu_index, &dbg);
 637 }
 638
 639
 640 /*
 641  * dirty pages logging
 642  */
 643 /* FIXME: use unsigned long pointer instead of unsigned char */
 644 unsigned char *kvm_dirty_bitmap = NULL;
 645 int kvm_physical_memory_set_dirty_tracking(int enable)
 646 {
 647     int r = 0;
 648
 649     if (!kvm_allowed)
 650         return 0;
 651
 652     if (enable) {
 653         if (!kvm_dirty_bitmap) {
 654             unsigned bitmap_size = BITMAP_SIZE(phys_ram_size);
 655             kvm_dirty_bitmap = qemu_malloc(bitmap_size);
 656             if (kvm_dirty_bitmap == NULL) {
 657                 perror("Failed to allocate dirty pages bitmap");
 658                 r=-1;
 659             }
 660             else {
 661                 r = kvm_dirty_pages_log_enable_all(kvm_context);
 662             }
 663         }
 664     }
 665     else {
 666         if (kvm_dirty_bitmap) {
 667             r = kvm_dirty_pages_log_reset(kvm_context);
 668             qemu_free(kvm_dirty_bitmap);
 669             kvm_dirty_bitmap = NULL;
 670         }
 671     }
 672     return r;
 673 }
 674
 675 /* get kvm's dirty pages bitmap and update qemu's */
 676 int kvm_get_dirty_pages_log_range(unsigned long start_addr,
 677                                   unsigned char *bitmap,
 678                                   unsigned int offset,
 679                                   unsigned long mem_size)
 680 {
 681     unsigned int i, j, n=0;
 682     unsigned char c;
 683     unsigned page_number, addr, addr1;
 684     unsigned int len = ((mem_size/TARGET_PAGE_SIZE) + 7) / 8;
 685
 686     /*
 687      * bitmap-traveling is faster than memory-traveling (for addr...)
 688      * especially when most of the memory is not dirty.
 689      */
 690     for (i=0; i<len; i++) {
 691         c = bitmap[i];
 692         while (c>0) {
 693             j = ffsl(c) - 1;
 694             c &= ~(1u<<j);
 695             page_number = i * 8 + j;
 696             addr1 = page_number * TARGET_PAGE_SIZE;
 697             addr  = offset + addr1;
 698             cpu_physical_memory_set_dirty(addr);
 699             n++;
 700         }
 701     }
 702     return 0;
 703 }
 704 int kvm_get_dirty_bitmap_cb(unsigned long start, unsigned long len,
 705                             void *bitmap, void *opaque)
 706 {
 707     return kvm_get_dirty_pages_log_range(start, bitmap, start, len);
 708 }
 709
 710 /*
 711  * get kvm's dirty pages bitmap and update qemu's
 712  * we only care about physical ram, which resides in slots 0 and 3
 713  */
 714 int kvm_update_dirty_pages_log(void)
 715 {
 716     int r = 0;
 717
 718
 719     r = kvm_get_dirty_pages_range(kvm_context, 0, phys_ram_size,
 720                                   kvm_dirty_bitmap, NULL,
 721                                   kvm_get_dirty_bitmap_cb);
 722     return r;
 723 }
 724
 725 int kvm_get_phys_ram_page_bitmap(unsigned char *bitmap)
 726 {
 727     unsigned int bsize  = BITMAP_SIZE(phys_ram_size);
 728     unsigned int brsize = BITMAP_SIZE(ram_size);
 729     unsigned int extra_pages = (phys_ram_size - ram_size) / TARGET_PAGE_SIZE;
 730     unsigned int extra_bytes = (extra_pages +7)/8;
 731     unsigned int hole_start = BITMAP_SIZE(0xa0000);
 732     unsigned int hole_end   = BITMAP_SIZE(0xc0000);
 733
 734     memset(bitmap, 0xFF, brsize + extra_bytes);
 735     memset(bitmap + hole_start, 0, hole_end - hole_start);
 736     memset(bitmap + brsize + extra_bytes, 0, bsize - brsize - extra_bytes);
 737
 738     return 0;
 739 }
 740
 741 #ifdef KVM_CAP_IRQCHIP
 742
 743 int kvm_set_irq(int irq, int level)
 744 {
 745     return kvm_set_irq_level(kvm_context, irq, level);
 746 }
 747
 748 #endif
 749
 750 #endif