qemu/kvm-all.c

   1 /*
   2  * QEMU KVM support
   3  *
   4  * Copyright IBM, Corp. 2008
   5  *           Red Hat, Inc. 2008
   6  *
   7  * Authors:
   8  *  Anthony Liguori   <aliguori@us.ibm.com>
   9  *  Glauber Costa     <gcosta@redhat.com>
  10  *
  11  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  12  * See the COPYING file in the top-level directory.
  13  *
  14  */
  15
  16 #include <sys/types.h>
  17 #include <sys/ioctl.h>
  18 #include <sys/mman.h>
  19 #include <stdarg.h>
  20
  21 #include <linux/kvm.h>
  22
  23 #include "qemu-common.h"
  24 #include "sysemu.h"
  25 #include "gdbstub.h"
  26 #include "kvm.h"
  27
  28 /* KVM uses PAGE_SIZE in it's definition of COALESCED_MMIO_MAX */
  29 #define PAGE_SIZE TARGET_PAGE_SIZE
  30
  31 //#define DEBUG_KVM
  32
  33 #ifdef DEBUG_KVM
  34 #define dprintf(fmt, ...) \
  35     do { fprintf(stderr, fmt, ## __VA_ARGS__); } while (0)
  36 #else
  37 #define dprintf(fmt, ...) \
  38     do { } while (0)
  39 #endif
  40
  41 typedef struct KVMSlot
  42 {
  43     target_phys_addr_t start_addr;
  44     ram_addr_t memory_size;
  45     ram_addr_t phys_offset;
  46     int slot;
  47     int flags;
  48 } KVMSlot;
  49
  50 typedef struct kvm_dirty_log KVMDirtyLog;
  51
  52 int kvm_allowed = 0;
  53
  54 struct KVMState
  55 {
  56     KVMSlot slots[32];
  57     int fd;
  58     int vmfd;
  59     int coalesced_mmio;
  60 #ifdef KVM_CAP_SET_GUEST_DEBUG
  61     struct kvm_sw_breakpoint_head kvm_sw_breakpoints;
  62 #endif
  63 };
  64
  65 static KVMState *kvm_state;
  66
  67 static KVMSlot *kvm_alloc_slot(KVMState *s)
  68 {
  69     int i;
  70
  71     for (i = 0; i < ARRAY_SIZE(s->slots); i++) {
  72         /* KVM private memory slots */
  73         if (i >= 8 && i < 12)
  74             continue;
  75         if (s->slots[i].memory_size == 0)
  76             return &s->slots[i];
  77     }
  78
  79     return NULL;
  80 }
  81
  82 static KVMSlot *kvm_lookup_slot(KVMState *s, target_phys_addr_t start_addr)
  83 {
  84     int i;
  85
  86     for (i = 0; i < ARRAY_SIZE(s->slots); i++) {
  87         KVMSlot *mem = &s->slots[i];
  88
  89         if (start_addr >= mem->start_addr &&
  90             start_addr < (mem->start_addr + mem->memory_size))
  91             return mem;
  92     }
  93
  94     return NULL;
  95 }
  96
  97 static int kvm_set_user_memory_region(KVMState *s, KVMSlot *slot)
  98 {
  99     struct kvm_userspace_memory_region mem;
 100
 101     mem.slot = slot->slot;
 102     mem.guest_phys_addr = slot->start_addr;
 103     mem.memory_size = slot->memory_size;
 104     mem.userspace_addr = (unsigned long)phys_ram_base + slot->phys_offset;
 105     mem.flags = slot->flags;
 106
 107     return kvm_vm_ioctl(s, KVM_SET_USER_MEMORY_REGION, &mem);
 108 }
 109
 110
 111 int kvm_init_vcpu(CPUState *env)
 112 {
 113     KVMState *s = kvm_state;
 114     long mmap_size;
 115     int ret;
 116
 117     dprintf("kvm_init_vcpu\n");
 118
 119     ret = kvm_vm_ioctl(s, KVM_CREATE_VCPU, env->cpu_index);
 120     if (ret < 0) {
 121         dprintf("kvm_create_vcpu failed\n");
 122         goto err;
 123     }
 124
 125     env->kvm_fd = ret;
 126     env->kvm_state = s;
 127
 128     mmap_size = kvm_ioctl(s, KVM_GET_VCPU_MMAP_SIZE, 0);
 129     if (mmap_size < 0) {
 130         dprintf("KVM_GET_VCPU_MMAP_SIZE failed\n");
 131         goto err;
 132     }
 133
 134     env->kvm_run = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED,
 135                         env->kvm_fd, 0);
 136     if (env->kvm_run == MAP_FAILED) {
 137         ret = -errno;
 138         dprintf("mmap'ing vcpu state failed\n");
 139         goto err;
 140     }
 141
 142     ret = kvm_arch_init_vcpu(env);
 143
 144 err:
 145     return ret;
 146 }
 147
 148 int kvm_sync_vcpus(void)
 149 {
 150     CPUState *env;
 151
 152     for (env = first_cpu; env != NULL; env = env->next_cpu) {
 153         int ret;
 154
 155         ret = kvm_arch_put_registers(env);
 156         if (ret)
 157             return ret;
 158     }
 159
 160     return 0;
 161 }
 162
 163 /*
 164  * dirty pages logging control
 165  */
 166 static int kvm_dirty_pages_log_change(target_phys_addr_t phys_addr, target_phys_addr_t end_addr,
 167                                       unsigned flags,
 168                                       unsigned mask)
 169 {
 170     KVMState *s = kvm_state;
 171     KVMSlot *mem = kvm_lookup_slot(s, phys_addr);
 172     if (mem == NULL)  {
 173             dprintf("invalid parameters %llx-%llx\n", phys_addr, end_addr);
 174             return -EINVAL;
 175     }
 176
 177     flags = (mem->flags & ~mask) | flags;
 178     /* Nothing changed, no need to issue ioctl */
 179     if (flags == mem->flags)
 180             return 0;
 181
 182     mem->flags = flags;
 183
 184     return kvm_set_user_memory_region(s, mem);
 185 }
 186
 187 int kvm_log_start(target_phys_addr_t phys_addr, target_phys_addr_t end_addr)
 188 {
 189         return kvm_dirty_pages_log_change(phys_addr, end_addr,
 190                                           KVM_MEM_LOG_DIRTY_PAGES,
 191                                           KVM_MEM_LOG_DIRTY_PAGES);
 192 }
 193
 194 int kvm_log_stop(target_phys_addr_t phys_addr, target_phys_addr_t end_addr)
 195 {
 196         return kvm_dirty_pages_log_change(phys_addr, end_addr,
 197                                           0,
 198                                           KVM_MEM_LOG_DIRTY_PAGES);
 199 }
 200
 201 /**
 202  * kvm_physical_sync_dirty_bitmap - Grab dirty bitmap from kernel space
 203  * This function updates qemu's dirty bitmap using cpu_physical_memory_set_dirty().
 204  * This means all bits are set to dirty.
 205  *
 206  * @start_add: start of logged region. This is what we use to search the memslot
 207  * @end_addr: end of logged region.
 208  */
 209 void kvm_physical_sync_dirty_bitmap(target_phys_addr_t start_addr, target_phys_addr_t end_addr)
 210 {
 211     KVMState *s = kvm_state;
 212     KVMDirtyLog d;
 213     KVMSlot *mem = kvm_lookup_slot(s, start_addr);
 214     unsigned long alloc_size;
 215     ram_addr_t addr;
 216     target_phys_addr_t phys_addr = start_addr;
 217
 218     dprintf("sync addr: %llx into %lx\n", start_addr, mem->phys_offset);
 219     if (mem == NULL) {
 220             fprintf(stderr, "BUG: %s: invalid parameters\n", __func__);
 221             return;
 222     }
 223
 224     alloc_size = mem->memory_size >> TARGET_PAGE_BITS / sizeof(d.dirty_bitmap);
 225     d.dirty_bitmap = qemu_mallocz(alloc_size);
 226
 227     d.slot = mem->slot;
 228     dprintf("slot %d, phys_addr %llx, uaddr: %llx\n",
 229             d.slot, mem->start_addr, mem->phys_offset);
 230
 231     if (kvm_vm_ioctl(s, KVM_GET_DIRTY_LOG, &d) == -1) {
 232         dprintf("ioctl failed %d\n", errno);
 233         goto out;
 234     }
 235
 236     phys_addr = start_addr;
 237     for (addr = mem->phys_offset; phys_addr < end_addr; phys_addr+= TARGET_PAGE_SIZE, addr += TARGET_PAGE_SIZE) {
 238         unsigned long *bitmap = (unsigned long *)d.dirty_bitmap;
 239         unsigned nr = (phys_addr - start_addr) >> TARGET_PAGE_BITS;
 240         unsigned word = nr / (sizeof(*bitmap) * 8);
 241         unsigned bit = nr % (sizeof(*bitmap) * 8);
 242         if ((bitmap[word] >> bit) & 1)
 243             cpu_physical_memory_set_dirty(addr);
 244     }
 245 out:
 246     qemu_free(d.dirty_bitmap);
 247 }
 248
 249 int kvm_coalesce_mmio_region(target_phys_addr_t start, ram_addr_t size)
 250 {
 251     int ret = -ENOSYS;
 252 #ifdef KVM_CAP_COALESCED_MMIO
 253     KVMState *s = kvm_state;
 254
 255     if (s->coalesced_mmio) {
 256         struct kvm_coalesced_mmio_zone zone;
 257
 258         zone.addr = start;
 259         zone.size = size;
 260
 261         ret = kvm_vm_ioctl(s, KVM_REGISTER_COALESCED_MMIO, &zone);
 262     }
 263 #endif
 264
 265     return ret;
 266 }
 267
 268 int kvm_uncoalesce_mmio_region(target_phys_addr_t start, ram_addr_t size)
 269 {
 270     int ret = -ENOSYS;
 271 #ifdef KVM_CAP_COALESCED_MMIO
 272     KVMState *s = kvm_state;
 273
 274     if (s->coalesced_mmio) {
 275         struct kvm_coalesced_mmio_zone zone;
 276
 277         zone.addr = start;
 278         zone.size = size;
 279
 280         ret = kvm_vm_ioctl(s, KVM_UNREGISTER_COALESCED_MMIO, &zone);
 281     }
 282 #endif
 283
 284     return ret;
 285 }
 286
 287 int kvm_init(int smp_cpus)
 288 {
 289     KVMState *s;
 290     int ret;
 291     int i;
 292
 293     if (smp_cpus > 1)
 294         return -EINVAL;
 295
 296     s = qemu_mallocz(sizeof(KVMState));
 297
 298 #ifdef KVM_CAP_SET_GUEST_DEBUG
 299     TAILQ_INIT(&s->kvm_sw_breakpoints);
 300 #endif
 301     for (i = 0; i < ARRAY_SIZE(s->slots); i++)
 302         s->slots[i].slot = i;
 303
 304     s->vmfd = -1;
 305     s->fd = open("/dev/kvm", O_RDWR);
 306     if (s->fd == -1) {
 307         fprintf(stderr, "Could not access KVM kernel module: %m\n");
 308         ret = -errno;
 309         goto err;
 310     }
 311
 312     ret = kvm_ioctl(s, KVM_GET_API_VERSION, 0);
 313     if (ret < KVM_API_VERSION) {
 314         if (ret > 0)
 315             ret = -EINVAL;
 316         fprintf(stderr, "kvm version too old\n");
 317         goto err;
 318     }
 319
 320     if (ret > KVM_API_VERSION) {
 321         ret = -EINVAL;
 322         fprintf(stderr, "kvm version not supported\n");
 323         goto err;
 324     }
 325
 326     s->vmfd = kvm_ioctl(s, KVM_CREATE_VM, 0);
 327     if (s->vmfd < 0)
 328         goto err;
 329
 330     /* initially, KVM allocated its own memory and we had to jump through
 331      * hooks to make phys_ram_base point to this.  Modern versions of KVM
 332      * just use a user allocated buffer so we can use phys_ram_base
 333      * unmodified.  Make sure we have a sufficiently modern version of KVM.
 334      */
 335     ret = kvm_ioctl(s, KVM_CHECK_EXTENSION, KVM_CAP_USER_MEMORY);
 336     if (ret <= 0) {
 337         if (ret == 0)
 338             ret = -EINVAL;
 339         fprintf(stderr, "kvm does not support KVM_CAP_USER_MEMORY\n");
 340         goto err;
 341     }
 342
 343     /* There was a nasty bug in < kvm-80 that prevents memory slots from being
 344      * destroyed properly.  Since we rely on this capability, refuse to work
 345      * with any kernel without this capability. */
 346     ret = kvm_ioctl(s, KVM_CHECK_EXTENSION,
 347                     KVM_CAP_DESTROY_MEMORY_REGION_WORKS);
 348     if (ret <= 0) {
 349         if (ret == 0)
 350             ret = -EINVAL;
 351
 352         fprintf(stderr,
 353                 "KVM kernel module broken (DESTROY_MEMORY_REGION)\n"
 354                 "Please upgrade to at least kvm-81.\n");
 355         goto err;
 356     }
 357
 358     s->coalesced_mmio = 0;
 359 #ifdef KVM_CAP_COALESCED_MMIO
 360     ret = kvm_ioctl(s, KVM_CHECK_EXTENSION, KVM_CAP_COALESCED_MMIO);
 361     if (ret > 0)
 362         s->coalesced_mmio = ret;
 363 #endif
 364
 365     ret = kvm_arch_init(s, smp_cpus);
 366     if (ret < 0)
 367         goto err;
 368
 369     kvm_state = s;
 370
 371     return 0;
 372
 373 err:
 374     if (s) {
 375         if (s->vmfd != -1)
 376             close(s->vmfd);
 377         if (s->fd != -1)
 378             close(s->fd);
 379     }
 380     qemu_free(s);
 381
 382     return ret;
 383 }
 384
 385 static int kvm_handle_io(CPUState *env, uint16_t port, void *data,
 386                          int direction, int size, uint32_t count)
 387 {
 388     int i;
 389     uint8_t *ptr = data;
 390
 391     for (i = 0; i < count; i++) {
 392         if (direction == KVM_EXIT_IO_IN) {
 393             switch (size) {
 394             case 1:
 395                 stb_p(ptr, cpu_inb(env, port));
 396                 break;
 397             case 2:
 398                 stw_p(ptr, cpu_inw(env, port));
 399                 break;
 400             case 4:
 401                 stl_p(ptr, cpu_inl(env, port));
 402                 break;
 403             }
 404         } else {
 405             switch (size) {
 406             case 1:
 407                 cpu_outb(env, port, ldub_p(ptr));
 408                 break;
 409             case 2:
 410                 cpu_outw(env, port, lduw_p(ptr));
 411                 break;
 412             case 4:
 413                 cpu_outl(env, port, ldl_p(ptr));
 414                 break;
 415             }
 416         }
 417
 418         ptr += size;
 419     }
 420
 421     return 1;
 422 }
 423
 424 static void kvm_run_coalesced_mmio(CPUState *env, struct kvm_run *run)
 425 {
 426 #ifdef KVM_CAP_COALESCED_MMIO
 427     KVMState *s = kvm_state;
 428     if (s->coalesced_mmio) {
 429         struct kvm_coalesced_mmio_ring *ring;
 430
 431         ring = (void *)run + (s->coalesced_mmio * TARGET_PAGE_SIZE);
 432         while (ring->first != ring->last) {
 433             struct kvm_coalesced_mmio *ent;
 434
 435             ent = &ring->coalesced_mmio[ring->first];
 436
 437             cpu_physical_memory_write(ent->phys_addr, ent->data, ent->len);
 438             /* FIXME smp_wmb() */
 439             ring->first = (ring->first + 1) % KVM_COALESCED_MMIO_MAX;
 440         }
 441     }
 442 #endif
 443 }
 444
 445 int kvm_cpu_exec(CPUState *env)
 446 {
 447     struct kvm_run *run = env->kvm_run;
 448     int ret;
 449
 450     dprintf("kvm_cpu_exec()\n");
 451
 452     do {
 453         kvm_arch_pre_run(env, run);
 454
 455         if (env->exit_request) {
 456             dprintf("interrupt exit requested\n");
 457             ret = 0;
 458             break;
 459         }
 460
 461         ret = kvm_vcpu_ioctl(env, KVM_RUN, 0);
 462         kvm_arch_post_run(env, run);
 463
 464         if (ret == -EINTR || ret == -EAGAIN) {
 465             dprintf("io window exit\n");
 466             ret = 0;
 467             break;
 468         }
 469
 470         if (ret < 0) {
 471             dprintf("kvm run failed %s\n", strerror(-ret));
 472             abort();
 473         }
 474
 475         kvm_run_coalesced_mmio(env, run);
 476
 477         ret = 0; /* exit loop */
 478         switch (run->exit_reason) {
 479         case KVM_EXIT_IO:
 480             dprintf("handle_io\n");
 481             ret = kvm_handle_io(env, run->io.port,
 482                                 (uint8_t *)run + run->io.data_offset,
 483                                 run->io.direction,
 484                                 run->io.size,
 485                                 run->io.count);
 486             break;
 487         case KVM_EXIT_MMIO:
 488             dprintf("handle_mmio\n");
 489             cpu_physical_memory_rw(run->mmio.phys_addr,
 490                                    run->mmio.data,
 491                                    run->mmio.len,
 492                                    run->mmio.is_write);
 493             ret = 1;
 494             break;
 495         case KVM_EXIT_IRQ_WINDOW_OPEN:
 496             dprintf("irq_window_open\n");
 497             break;
 498         case KVM_EXIT_SHUTDOWN:
 499             dprintf("shutdown\n");
 500             qemu_system_reset_request();
 501             ret = 1;
 502             break;
 503         case KVM_EXIT_UNKNOWN:
 504             dprintf("kvm_exit_unknown\n");
 505             break;
 506         case KVM_EXIT_FAIL_ENTRY:
 507             dprintf("kvm_exit_fail_entry\n");
 508             break;
 509         case KVM_EXIT_EXCEPTION:
 510             dprintf("kvm_exit_exception\n");
 511             break;
 512         case KVM_EXIT_DEBUG:
 513             dprintf("kvm_exit_debug\n");
 514 #ifdef KVM_CAP_SET_GUEST_DEBUG
 515             if (kvm_arch_debug(&run->debug.arch)) {
 516                 gdb_set_stop_cpu(env);
 517                 vm_stop(EXCP_DEBUG);
 518                 env->exception_index = EXCP_DEBUG;
 519                 return 0;
 520             }
 521             /* re-enter, this exception was guest-internal */
 522             ret = 1;
 523 #endif /* KVM_CAP_SET_GUEST_DEBUG */
 524             break;
 525         default:
 526             dprintf("kvm_arch_handle_exit\n");
 527             ret = kvm_arch_handle_exit(env, run);
 528             break;
 529         }
 530     } while (ret > 0);
 531
 532     if (env->exit_request) {
 533         env->exit_request = 0;
 534         env->exception_index = EXCP_INTERRUPT;
 535     }
 536
 537     return ret;
 538 }
 539
 540 void kvm_set_phys_mem(target_phys_addr_t start_addr,
 541                       ram_addr_t size,
 542                       ram_addr_t phys_offset)
 543 {
 544     KVMState *s = kvm_state;
 545     ram_addr_t flags = phys_offset & ~TARGET_PAGE_MASK;
 546     KVMSlot *mem;
 547
 548     /* KVM does not support read-only slots */
 549     phys_offset &= ~IO_MEM_ROM;
 550
 551     mem = kvm_lookup_slot(s, start_addr);
 552     if (mem) {
 553         if ((flags == IO_MEM_UNASSIGNED) || (flags >= TLB_MMIO)) {
 554             mem->memory_size = 0;
 555             mem->start_addr = start_addr;
 556             mem->phys_offset = 0;
 557             mem->flags = 0;
 558
 559             kvm_set_user_memory_region(s, mem);
 560         } else if (start_addr >= mem->start_addr &&
 561                    (start_addr + size) <= (mem->start_addr +
 562                                            mem->memory_size)) {
 563             KVMSlot slot;
 564             target_phys_addr_t mem_start;
 565             ram_addr_t mem_size, mem_offset;
 566
 567             /* Not splitting */
 568             if ((phys_offset - (start_addr - mem->start_addr)) ==
 569                 mem->phys_offset)
 570                 return;
 571
 572             /* unregister whole slot */
 573             memcpy(&slot, mem, sizeof(slot));
 574             mem->memory_size = 0;
 575             kvm_set_user_memory_region(s, mem);
 576
 577             /* register prefix slot */
 578             mem_start = slot.start_addr;
 579             mem_size = start_addr - slot.start_addr;
 580             mem_offset = slot.phys_offset;
 581             if (mem_size)
 582                 kvm_set_phys_mem(mem_start, mem_size, mem_offset);
 583
 584             /* register new slot */
 585             kvm_set_phys_mem(start_addr, size, phys_offset);
 586
 587             /* register suffix slot */
 588             mem_start = start_addr + size;
 589             mem_offset += mem_size + size;
 590             mem_size = slot.memory_size - mem_size - size;
 591             if (mem_size)
 592                 kvm_set_phys_mem(mem_start, mem_size, mem_offset);
 593
 594             return;
 595         } else {
 596             printf("Registering overlapping slot\n");
 597             abort();
 598         }
 599     }
 600     /* KVM does not need to know about this memory */
 601     if (flags >= IO_MEM_UNASSIGNED)
 602         return;
 603
 604     mem = kvm_alloc_slot(s);
 605     mem->memory_size = size;
 606     mem->start_addr = start_addr;
 607     mem->phys_offset = phys_offset;
 608     mem->flags = 0;
 609
 610     kvm_set_user_memory_region(s, mem);
 611     /* FIXME deal with errors */
 612 }
 613
 614 int kvm_ioctl(KVMState *s, int type, ...)
 615 {
 616     int ret;
 617     void *arg;
 618     va_list ap;
 619
 620     va_start(ap, type);
 621     arg = va_arg(ap, void *);
 622     va_end(ap);
 623
 624     ret = ioctl(s->fd, type, arg);
 625     if (ret == -1)
 626         ret = -errno;
 627
 628     return ret;
 629 }
 630
 631 int kvm_vm_ioctl(KVMState *s, int type, ...)
 632 {
 633     int ret;
 634     void *arg;
 635     va_list ap;
 636
 637     va_start(ap, type);
 638     arg = va_arg(ap, void *);
 639     va_end(ap);
 640
 641     ret = ioctl(s->vmfd, type, arg);
 642     if (ret == -1)
 643         ret = -errno;
 644
 645     return ret;
 646 }
 647
 648 int kvm_vcpu_ioctl(CPUState *env, int type, ...)
 649 {
 650     int ret;
 651     void *arg;
 652     va_list ap;
 653
 654     va_start(ap, type);
 655     arg = va_arg(ap, void *);
 656     va_end(ap);
 657
 658     ret = ioctl(env->kvm_fd, type, arg);
 659     if (ret == -1)
 660         ret = -errno;
 661
 662     return ret;
 663 }
 664
 665 int kvm_has_sync_mmu(void)
 666 {
 667 #ifdef KVM_CAP_SYNC_MMU
 668     KVMState *s = kvm_state;
 669
 670     if (kvm_ioctl(s, KVM_CHECK_EXTENSION, KVM_CAP_SYNC_MMU) > 0)
 671         return 1;
 672 #endif
 673
 674     return 0;
 675 }
 676
 677 #ifdef KVM_CAP_SET_GUEST_DEBUG
 678 struct kvm_sw_breakpoint *kvm_find_sw_breakpoint(CPUState *env,
 679                                                  target_ulong pc)
 680 {
 681     struct kvm_sw_breakpoint *bp;
 682
 683     TAILQ_FOREACH(bp, &env->kvm_state->kvm_sw_breakpoints, entry) {
 684         if (bp->pc == pc)
 685             return bp;
 686     }
 687     return NULL;
 688 }
 689
 690 int kvm_sw_breakpoints_active(CPUState *env)
 691 {
 692     return !TAILQ_EMPTY(&env->kvm_state->kvm_sw_breakpoints);
 693 }
 694
 695 int kvm_update_guest_debug(CPUState *env, unsigned long reinject_trap)
 696 {
 697     struct kvm_guest_debug dbg;
 698
 699     dbg.control = 0;
 700     if (env->singlestep_enabled)
 701         dbg.control = KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_SINGLESTEP;
 702
 703     kvm_arch_update_guest_debug(env, &dbg);
 704     dbg.control |= reinject_trap;
 705
 706     return kvm_vcpu_ioctl(env, KVM_SET_GUEST_DEBUG, &dbg);
 707 }
 708
 709 int kvm_insert_breakpoint(CPUState *current_env, target_ulong addr,
 710                           target_ulong len, int type)
 711 {
 712     struct kvm_sw_breakpoint *bp;
 713     CPUState *env;
 714     int err;
 715
 716     if (type == GDB_BREAKPOINT_SW) {
 717         bp = kvm_find_sw_breakpoint(current_env, addr);
 718         if (bp) {
 719             bp->use_count++;
 720             return 0;
 721         }
 722
 723         bp = qemu_malloc(sizeof(struct kvm_sw_breakpoint));
 724         if (!bp)
 725             return -ENOMEM;
 726
 727         bp->pc = addr;
 728         bp->use_count = 1;
 729         err = kvm_arch_insert_sw_breakpoint(current_env, bp);
 730         if (err) {
 731             free(bp);
 732             return err;
 733         }
 734
 735         TAILQ_INSERT_HEAD(&current_env->kvm_state->kvm_sw_breakpoints,
 736                           bp, entry);
 737     } else {
 738         err = kvm_arch_insert_hw_breakpoint(addr, len, type);
 739         if (err)
 740             return err;
 741     }
 742
 743     for (env = first_cpu; env != NULL; env = env->next_cpu) {
 744         err = kvm_update_guest_debug(env, 0);
 745         if (err)
 746             return err;
 747     }
 748     return 0;
 749 }
 750
 751 int kvm_remove_breakpoint(CPUState *current_env, target_ulong addr,
 752                           target_ulong len, int type)
 753 {
 754     struct kvm_sw_breakpoint *bp;
 755     CPUState *env;
 756     int err;
 757
 758     if (type == GDB_BREAKPOINT_SW) {
 759         bp = kvm_find_sw_breakpoint(current_env, addr);
 760         if (!bp)
 761             return -ENOENT;
 762
 763         if (bp->use_count > 1) {
 764             bp->use_count--;
 765             return 0;
 766         }
 767
 768         err = kvm_arch_remove_sw_breakpoint(current_env, bp);
 769         if (err)
 770             return err;
 771
 772         TAILQ_REMOVE(&current_env->kvm_state->kvm_sw_breakpoints, bp, entry);
 773         qemu_free(bp);
 774     } else {
 775         err = kvm_arch_remove_hw_breakpoint(addr, len, type);
 776         if (err)
 777             return err;
 778     }
 779
 780     for (env = first_cpu; env != NULL; env = env->next_cpu) {
 781         err = kvm_update_guest_debug(env, 0);
 782         if (err)
 783             return err;
 784     }
 785     return 0;
 786 }
 787
 788 void kvm_remove_all_breakpoints(CPUState *current_env)
 789 {
 790     struct kvm_sw_breakpoint *bp, *next;
 791     KVMState *s = current_env->kvm_state;
 792     CPUState *env;
 793
 794     TAILQ_FOREACH_SAFE(bp, &s->kvm_sw_breakpoints, entry, next) {
 795         if (kvm_arch_remove_sw_breakpoint(current_env, bp) != 0) {
 796             /* Try harder to find a CPU that currently sees the breakpoint. */
 797             for (env = first_cpu; env != NULL; env = env->next_cpu) {
 798                 if (kvm_arch_remove_sw_breakpoint(env, bp) == 0)
 799                     break;
 800             }
 801         }
 802     }
 803     kvm_arch_remove_all_hw_breakpoints();
 804
 805     for (env = first_cpu; env != NULL; env = env->next_cpu)
 806         kvm_update_guest_debug(env, 0);
 807 }
 808
 809 #else /* !KVM_CAP_SET_GUEST_DEBUG */
 810
 811 int kvm_update_guest_debug(CPUState *env, unsigned long reinject_trap)
 812 {
 813     return -EINVAL;
 814 }
 815
 816 int kvm_insert_breakpoint(CPUState *current_env, target_ulong addr,
 817                           target_ulong len, int type)
 818 {
 819     return -EINVAL;
 820 }
 821
 822 int kvm_remove_breakpoint(CPUState *current_env, target_ulong addr,
 823                           target_ulong len, int type)
 824 {
 825     return -EINVAL;
 826 }
 827
 828 void kvm_remove_all_breakpoints(CPUState *current_env)
 829 {
 830 }
 831 #endif /* !KVM_CAP_SET_GUEST_DEBUG */