hw/misc/ivshmem.c

   1 /*
   2  * Inter-VM Shared Memory PCI device.
   3  *
   4  * Author:
   5  *      Cam Macdonell <cam@cs.ualberta.ca>
   6  *
   7  * Based On: cirrus_vga.c
   8  *          Copyright (c) 2004 Fabrice Bellard
   9  *          Copyright (c) 2004 Makoto Suzuki (suzu)
  10  *
  11  *      and rtl8139.c
  12  *          Copyright (c) 2006 Igor Kovalenko
  13  *
  14  * This code is licensed under the GNU GPL v2.
  15  *
  16  * Contributions after 2012-01-13 are licensed under the terms of the
  17  * GNU GPL, version 2 or (at your option) any later version.
  18  */
  19 #include "hw/hw.h"
  20 #include "hw/i386/pc.h"
  21 #include "hw/pci/pci.h"
  22 #include "hw/pci/msix.h"
  23 #include "sysemu/kvm.h"
  24 #include "migration/migration.h"
  25 #include "qapi/qmp/qerror.h"
  26 #include "qemu/event_notifier.h"
  27 #include "sysemu/char.h"
  28
  29 #include <sys/mman.h>
  30 #include <sys/types.h>
  31
  32 #define PCI_VENDOR_ID_IVSHMEM   PCI_VENDOR_ID_REDHAT_QUMRANET
  33 #define PCI_DEVICE_ID_IVSHMEM   0x1110
  34
  35 #define IVSHMEM_IOEVENTFD   0
  36 #define IVSHMEM_MSI     1
  37
  38 #define IVSHMEM_PEER    0
  39 #define IVSHMEM_MASTER  1
  40
  41 #define IVSHMEM_REG_BAR_SIZE 0x100
  42
  43 //#define DEBUG_IVSHMEM
  44 #ifdef DEBUG_IVSHMEM
  45 #define IVSHMEM_DPRINTF(fmt, ...)        \
  46     do {printf("IVSHMEM: " fmt, ## __VA_ARGS__); } while (0)
  47 #else
  48 #define IVSHMEM_DPRINTF(fmt, ...)
  49 #endif
  50
  51 typedef struct Peer {
  52     int nb_eventfds;
  53     EventNotifier *eventfds;
  54 } Peer;
  55
  56 typedef struct EventfdEntry {
  57     PCIDevice *pdev;
  58     int vector;
  59 } EventfdEntry;
  60
  61 typedef struct IVShmemState {
  62     PCIDevice dev;
  63     uint32_t intrmask;
  64     uint32_t intrstatus;
  65     uint32_t doorbell;
  66
  67     CharDriverState **eventfd_chr;
  68     CharDriverState *server_chr;
  69     MemoryRegion ivshmem_mmio;
  70
  71     /* We might need to register the BAR before we actually have the memory.
  72      * So prepare a container MemoryRegion for the BAR immediately and
  73      * add a subregion when we have the memory.
  74      */
  75     MemoryRegion bar;
  76     MemoryRegion ivshmem;
  77     uint64_t ivshmem_size; /* size of shared memory region */
  78     uint32_t ivshmem_attr;
  79     uint32_t ivshmem_64bit;
  80     int shm_fd; /* shared memory file descriptor */
  81
  82     Peer *peers;
  83     int nb_peers; /* how many guests we have space for */
  84     int max_peer; /* maximum numbered peer */
  85
  86     int vm_id;
  87     uint32_t vectors;
  88     uint32_t features;
  89     EventfdEntry *eventfd_table;
  90
  91     Error *migration_blocker;
  92
  93     char * shmobj;
  94     char * sizearg;
  95     char * role;
  96     int role_val;   /* scalar to avoid multiple string comparisons */
  97 } IVShmemState;
  98
  99 /* registers for the Inter-VM shared memory device */
 100 enum ivshmem_registers {
 101     INTRMASK = 0,
 102     INTRSTATUS = 4,
 103     IVPOSITION = 8,
 104     DOORBELL = 12,
 105 };
 106
 107 static inline uint32_t ivshmem_has_feature(IVShmemState *ivs,
 108                                                     unsigned int feature) {
 109     return (ivs->features & (1 << feature));
 110 }
 111
 112 static inline bool is_power_of_two(uint64_t x) {
 113     return (x & (x - 1)) == 0;
 114 }
 115
 116 /* accessing registers - based on rtl8139 */
 117 static void ivshmem_update_irq(IVShmemState *s, int val)
 118 {
 119     int isr;
 120     isr = (s->intrstatus & s->intrmask) & 0xffffffff;
 121
 122     /* don't print ISR resets */
 123     if (isr) {
 124         IVSHMEM_DPRINTF("Set IRQ to %d (%04x %04x)\n",
 125            isr ? 1 : 0, s->intrstatus, s->intrmask);
 126     }
 127
 128     qemu_set_irq(s->dev.irq[0], (isr != 0));
 129 }
 130
 131 static void ivshmem_IntrMask_write(IVShmemState *s, uint32_t val)
 132 {
 133     IVSHMEM_DPRINTF("IntrMask write(w) val = 0x%04x\n", val);
 134
 135     s->intrmask = val;
 136
 137     ivshmem_update_irq(s, val);
 138 }
 139
 140 static uint32_t ivshmem_IntrMask_read(IVShmemState *s)
 141 {
 142     uint32_t ret = s->intrmask;
 143
 144     IVSHMEM_DPRINTF("intrmask read(w) val = 0x%04x\n", ret);
 145
 146     return ret;
 147 }
 148
 149 static void ivshmem_IntrStatus_write(IVShmemState *s, uint32_t val)
 150 {
 151     IVSHMEM_DPRINTF("IntrStatus write(w) val = 0x%04x\n", val);
 152
 153     s->intrstatus = val;
 154
 155     ivshmem_update_irq(s, val);
 156 }
 157
 158 static uint32_t ivshmem_IntrStatus_read(IVShmemState *s)
 159 {
 160     uint32_t ret = s->intrstatus;
 161
 162     /* reading ISR clears all interrupts */
 163     s->intrstatus = 0;
 164
 165     ivshmem_update_irq(s, 0);
 166
 167     return ret;
 168 }
 169
 170 static void ivshmem_io_write(void *opaque, hwaddr addr,
 171                              uint64_t val, unsigned size)
 172 {
 173     IVShmemState *s = opaque;
 174
 175     uint16_t dest = val >> 16;
 176     uint16_t vector = val & 0xff;
 177
 178     addr &= 0xfc;
 179
 180     IVSHMEM_DPRINTF("writing to addr " TARGET_FMT_plx "\n", addr);
 181     switch (addr)
 182     {
 183         case INTRMASK:
 184             ivshmem_IntrMask_write(s, val);
 185             break;
 186
 187         case INTRSTATUS:
 188             ivshmem_IntrStatus_write(s, val);
 189             break;
 190
 191         case DOORBELL:
 192             /* check that dest VM ID is reasonable */
 193             if (dest > s->max_peer) {
 194                 IVSHMEM_DPRINTF("Invalid destination VM ID (%d)\n", dest);
 195                 break;
 196             }
 197
 198             /* check doorbell range */
 199             if (vector < s->peers[dest].nb_eventfds) {
 200                 IVSHMEM_DPRINTF("Notifying VM %d on vector %d\n", dest, vector);
 201                 event_notifier_set(&s->peers[dest].eventfds[vector]);
 202             }
 203             break;
 204         default:
 205             IVSHMEM_DPRINTF("Invalid VM Doorbell VM %d\n", dest);
 206     }
 207 }
 208
 209 static uint64_t ivshmem_io_read(void *opaque, hwaddr addr,
 210                                 unsigned size)
 211 {
 212
 213     IVShmemState *s = opaque;
 214     uint32_t ret;
 215
 216     switch (addr)
 217     {
 218         case INTRMASK:
 219             ret = ivshmem_IntrMask_read(s);
 220             break;
 221
 222         case INTRSTATUS:
 223             ret = ivshmem_IntrStatus_read(s);
 224             break;
 225
 226         case IVPOSITION:
 227             /* return my VM ID if the memory is mapped */
 228             if (s->shm_fd > 0) {
 229                 ret = s->vm_id;
 230             } else {
 231                 ret = -1;
 232             }
 233             break;
 234
 235         default:
 236             IVSHMEM_DPRINTF("why are we reading " TARGET_FMT_plx "\n", addr);
 237             ret = 0;
 238     }
 239
 240     return ret;
 241 }
 242
 243 static const MemoryRegionOps ivshmem_mmio_ops = {
 244     .read = ivshmem_io_read,
 245     .write = ivshmem_io_write,
 246     .endianness = DEVICE_NATIVE_ENDIAN,
 247     .impl = {
 248         .min_access_size = 4,
 249         .max_access_size = 4,
 250     },
 251 };
 252
 253 static void ivshmem_receive(void *opaque, const uint8_t *buf, int size)
 254 {
 255     IVShmemState *s = opaque;
 256
 257     ivshmem_IntrStatus_write(s, *buf);
 258
 259     IVSHMEM_DPRINTF("ivshmem_receive 0x%02x\n", *buf);
 260 }
 261
 262 static int ivshmem_can_receive(void * opaque)
 263 {
 264     return 8;
 265 }
 266
 267 static void ivshmem_event(void *opaque, int event)
 268 {
 269     IVSHMEM_DPRINTF("ivshmem_event %d\n", event);
 270 }
 271
 272 static void fake_irqfd(void *opaque, const uint8_t *buf, int size) {
 273
 274     EventfdEntry *entry = opaque;
 275     PCIDevice *pdev = entry->pdev;
 276
 277     IVSHMEM_DPRINTF("interrupt on vector %p %d\n", pdev, entry->vector);
 278     msix_notify(pdev, entry->vector);
 279 }
 280
 281 static CharDriverState* create_eventfd_chr_device(void * opaque, EventNotifier *n,
 282                                                   int vector)
 283 {
 284     /* create a event character device based on the passed eventfd */
 285     IVShmemState *s = opaque;
 286     CharDriverState * chr;
 287     int eventfd = event_notifier_get_fd(n);
 288
 289     chr = qemu_chr_open_eventfd(eventfd);
 290
 291     if (chr == NULL) {
 292         fprintf(stderr, "creating eventfd for eventfd %d failed\n", eventfd);
 293         exit(-1);
 294     }
 295     qemu_chr_fe_claim_no_fail(chr);
 296
 297     /* if MSI is supported we need multiple interrupts */
 298     if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
 299         s->eventfd_table[vector].pdev = &s->dev;
 300         s->eventfd_table[vector].vector = vector;
 301
 302         qemu_chr_add_handlers(chr, ivshmem_can_receive, fake_irqfd,
 303                       ivshmem_event, &s->eventfd_table[vector]);
 304     } else {
 305         qemu_chr_add_handlers(chr, ivshmem_can_receive, ivshmem_receive,
 306                       ivshmem_event, s);
 307     }
 308
 309     return chr;
 310
 311 }
 312
 313 static int check_shm_size(IVShmemState *s, int fd) {
 314     /* check that the guest isn't going to try and map more memory than the
 315      * the object has allocated return -1 to indicate error */
 316
 317     struct stat buf;
 318
 319     fstat(fd, &buf);
 320
 321     if (s->ivshmem_size > buf.st_size) {
 322         fprintf(stderr,
 323                 "IVSHMEM ERROR: Requested memory size greater"
 324                 " than shared object size (%" PRIu64 " > %" PRIu64")\n",
 325                 s->ivshmem_size, (uint64_t)buf.st_size);
 326         return -1;
 327     } else {
 328         return 0;
 329     }
 330 }
 331
 332 /* create the shared memory BAR when we are not using the server, so we can
 333  * create the BAR and map the memory immediately */
 334 static void create_shared_memory_BAR(IVShmemState *s, int fd) {
 335
 336     void * ptr;
 337
 338     s->shm_fd = fd;
 339
 340     ptr = mmap(0, s->ivshmem_size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
 341
 342     memory_region_init_ram_ptr(&s->ivshmem, OBJECT(s), "ivshmem.bar2",
 343                                s->ivshmem_size, ptr);
 344     vmstate_register_ram(&s->ivshmem, &s->dev.qdev);
 345     memory_region_add_subregion(&s->bar, 0, &s->ivshmem);
 346
 347     /* region for shared memory */
 348     pci_register_bar(&s->dev, 2, s->ivshmem_attr, &s->bar);
 349 }
 350
 351 static void ivshmem_add_eventfd(IVShmemState *s, int posn, int i)
 352 {
 353     memory_region_add_eventfd(&s->ivshmem_mmio,
 354                               DOORBELL,
 355                               4,
 356                               true,
 357                               (posn << 16) | i,
 358                               &s->peers[posn].eventfds[i]);
 359 }
 360
 361 static void ivshmem_del_eventfd(IVShmemState *s, int posn, int i)
 362 {
 363     memory_region_del_eventfd(&s->ivshmem_mmio,
 364                               DOORBELL,
 365                               4,
 366                               true,
 367                               (posn << 16) | i,
 368                               &s->peers[posn].eventfds[i]);
 369 }
 370
 371 static void close_guest_eventfds(IVShmemState *s, int posn)
 372 {
 373     int i, guest_curr_max;
 374
 375     if (!ivshmem_has_feature(s, IVSHMEM_IOEVENTFD)) {
 376         return;
 377     }
 378
 379     guest_curr_max = s->peers[posn].nb_eventfds;
 380
 381     memory_region_transaction_begin();
 382     for (i = 0; i < guest_curr_max; i++) {
 383         ivshmem_del_eventfd(s, posn, i);
 384     }
 385     memory_region_transaction_commit();
 386     for (i = 0; i < guest_curr_max; i++) {
 387         event_notifier_cleanup(&s->peers[posn].eventfds[i]);
 388     }
 389
 390     g_free(s->peers[posn].eventfds);
 391     s->peers[posn].nb_eventfds = 0;
 392 }
 393
 394 /* this function increase the dynamic storage need to store data about other
 395  * guests */
 396 static void increase_dynamic_storage(IVShmemState *s, int new_min_size) {
 397
 398     int j, old_nb_alloc;
 399
 400     old_nb_alloc = s->nb_peers;
 401
 402     while (new_min_size >= s->nb_peers)
 403         s->nb_peers = s->nb_peers * 2;
 404
 405     IVSHMEM_DPRINTF("bumping storage to %d guests\n", s->nb_peers);
 406     s->peers = g_realloc(s->peers, s->nb_peers * sizeof(Peer));
 407
 408     /* zero out new pointers */
 409     for (j = old_nb_alloc; j < s->nb_peers; j++) {
 410         s->peers[j].eventfds = NULL;
 411         s->peers[j].nb_eventfds = 0;
 412     }
 413 }
 414
 415 static void ivshmem_read(void *opaque, const uint8_t * buf, int flags)
 416 {
 417     IVShmemState *s = opaque;
 418     int incoming_fd, tmp_fd;
 419     int guest_max_eventfd;
 420     long incoming_posn;
 421
 422     memcpy(&incoming_posn, buf, sizeof(long));
 423     /* pick off s->server_chr->msgfd and store it, posn should accompany msg */
 424     tmp_fd = qemu_chr_fe_get_msgfd(s->server_chr);
 425     IVSHMEM_DPRINTF("posn is %ld, fd is %d\n", incoming_posn, tmp_fd);
 426
 427     /* make sure we have enough space for this guest */
 428     if (incoming_posn >= s->nb_peers) {
 429         increase_dynamic_storage(s, incoming_posn);
 430     }
 431
 432     if (tmp_fd == -1) {
 433         /* if posn is positive and unseen before then this is our posn*/
 434         if ((incoming_posn >= 0) &&
 435                             (s->peers[incoming_posn].eventfds == NULL)) {
 436             /* receive our posn */
 437             s->vm_id = incoming_posn;
 438             return;
 439         } else {
 440             /* otherwise an fd == -1 means an existing guest has gone away */
 441             IVSHMEM_DPRINTF("posn %ld has gone away\n", incoming_posn);
 442             close_guest_eventfds(s, incoming_posn);
 443             return;
 444         }
 445     }
 446
 447     /* because of the implementation of get_msgfd, we need a dup */
 448     incoming_fd = dup(tmp_fd);
 449
 450     if (incoming_fd == -1) {
 451         fprintf(stderr, "could not allocate file descriptor %s\n",
 452                                                             strerror(errno));
 453         return;
 454     }
 455
 456     /* if the position is -1, then it's shared memory region fd */
 457     if (incoming_posn == -1) {
 458
 459         void * map_ptr;
 460
 461         s->max_peer = 0;
 462
 463         if (check_shm_size(s, incoming_fd) == -1) {
 464             exit(-1);
 465         }
 466
 467         /* mmap the region and map into the BAR2 */
 468         map_ptr = mmap(0, s->ivshmem_size, PROT_READ|PROT_WRITE, MAP_SHARED,
 469                                                             incoming_fd, 0);
 470         memory_region_init_ram_ptr(&s->ivshmem, OBJECT(s),
 471                                    "ivshmem.bar2", s->ivshmem_size, map_ptr);
 472         vmstate_register_ram(&s->ivshmem, &s->dev.qdev);
 473
 474         IVSHMEM_DPRINTF("guest h/w addr = %" PRIu64 ", size = %" PRIu64 "\n",
 475                          s->ivshmem_offset, s->ivshmem_size);
 476
 477         memory_region_add_subregion(&s->bar, 0, &s->ivshmem);
 478
 479         /* only store the fd if it is successfully mapped */
 480         s->shm_fd = incoming_fd;
 481
 482         return;
 483     }
 484
 485     /* each guest has an array of eventfds, and we keep track of how many
 486      * guests for each VM */
 487     guest_max_eventfd = s->peers[incoming_posn].nb_eventfds;
 488
 489     if (guest_max_eventfd == 0) {
 490         /* one eventfd per MSI vector */
 491         s->peers[incoming_posn].eventfds = g_new(EventNotifier, s->vectors);
 492     }
 493
 494     /* this is an eventfd for a particular guest VM */
 495     IVSHMEM_DPRINTF("eventfds[%ld][%d] = %d\n", incoming_posn,
 496                                             guest_max_eventfd, incoming_fd);
 497     event_notifier_init_fd(&s->peers[incoming_posn].eventfds[guest_max_eventfd],
 498                            incoming_fd);
 499
 500     /* increment count for particular guest */
 501     s->peers[incoming_posn].nb_eventfds++;
 502
 503     /* keep track of the maximum VM ID */
 504     if (incoming_posn > s->max_peer) {
 505         s->max_peer = incoming_posn;
 506     }
 507
 508     if (incoming_posn == s->vm_id) {
 509         s->eventfd_chr[guest_max_eventfd] = create_eventfd_chr_device(s,
 510                    &s->peers[s->vm_id].eventfds[guest_max_eventfd],
 511                    guest_max_eventfd);
 512     }
 513
 514     if (ivshmem_has_feature(s, IVSHMEM_IOEVENTFD)) {
 515         ivshmem_add_eventfd(s, incoming_posn, guest_max_eventfd);
 516     }
 517 }
 518
 519 /* Select the MSI-X vectors used by device.
 520  * ivshmem maps events to vectors statically, so
 521  * we just enable all vectors on init and after reset. */
 522 static void ivshmem_use_msix(IVShmemState * s)
 523 {
 524     int i;
 525
 526     if (!msix_present(&s->dev)) {
 527         return;
 528     }
 529
 530     for (i = 0; i < s->vectors; i++) {
 531         msix_vector_use(&s->dev, i);
 532     }
 533 }
 534
 535 static void ivshmem_reset(DeviceState *d)
 536 {
 537     IVShmemState *s = DO_UPCAST(IVShmemState, dev.qdev, d);
 538
 539     s->intrstatus = 0;
 540     ivshmem_use_msix(s);
 541 }
 542
 543 static uint64_t ivshmem_get_size(IVShmemState * s) {
 544
 545     uint64_t value;
 546     char *ptr;
 547
 548     value = strtoull(s->sizearg, &ptr, 10);
 549     switch (*ptr) {
 550         case 0: case 'M': case 'm':
 551             value <<= 20;
 552             break;
 553         case 'G': case 'g':
 554             value <<= 30;
 555             break;
 556         default:
 557             fprintf(stderr, "qemu: invalid ram size: %s\n", s->sizearg);
 558             exit(1);
 559     }
 560
 561     /* BARs must be a power of 2 */
 562     if (!is_power_of_two(value)) {
 563         fprintf(stderr, "ivshmem: size must be power of 2\n");
 564         exit(1);
 565     }
 566
 567     return value;
 568 }
 569
 570 static void ivshmem_setup_msi(IVShmemState * s)
 571 {
 572     if (msix_init_exclusive_bar(&s->dev, s->vectors, 1)) {
 573         IVSHMEM_DPRINTF("msix initialization failed\n");
 574         exit(1);
 575     }
 576
 577     IVSHMEM_DPRINTF("msix initialized (%d vectors)\n", s->vectors);
 578
 579     /* allocate QEMU char devices for receiving interrupts */
 580     s->eventfd_table = g_malloc0(s->vectors * sizeof(EventfdEntry));
 581
 582     ivshmem_use_msix(s);
 583 }
 584
 585 static void ivshmem_save(QEMUFile* f, void *opaque)
 586 {
 587     IVShmemState *proxy = opaque;
 588
 589     IVSHMEM_DPRINTF("ivshmem_save\n");
 590     pci_device_save(&proxy->dev, f);
 591
 592     if (ivshmem_has_feature(proxy, IVSHMEM_MSI)) {
 593         msix_save(&proxy->dev, f);
 594     } else {
 595         qemu_put_be32(f, proxy->intrstatus);
 596         qemu_put_be32(f, proxy->intrmask);
 597     }
 598
 599 }
 600
 601 static int ivshmem_load(QEMUFile* f, void *opaque, int version_id)
 602 {
 603     IVSHMEM_DPRINTF("ivshmem_load\n");
 604
 605     IVShmemState *proxy = opaque;
 606     int ret;
 607
 608     if (version_id > 0) {
 609         return -EINVAL;
 610     }
 611
 612     if (proxy->role_val == IVSHMEM_PEER) {
 613         fprintf(stderr, "ivshmem: 'peer' devices are not migratable\n");
 614         return -EINVAL;
 615     }
 616
 617     ret = pci_device_load(&proxy->dev, f);
 618     if (ret) {
 619         return ret;
 620     }
 621
 622     if (ivshmem_has_feature(proxy, IVSHMEM_MSI)) {
 623         msix_load(&proxy->dev, f);
 624         ivshmem_use_msix(proxy);
 625     } else {
 626         proxy->intrstatus = qemu_get_be32(f);
 627         proxy->intrmask = qemu_get_be32(f);
 628     }
 629
 630     return 0;
 631 }
 632
 633 static void ivshmem_write_config(PCIDevice *pci_dev, uint32_t address,
 634                                  uint32_t val, int len)
 635 {
 636     pci_default_write_config(pci_dev, address, val, len);
 637     msix_write_config(pci_dev, address, val, len);
 638 }
 639
 640 static int pci_ivshmem_init(PCIDevice *dev)
 641 {
 642     IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
 643     uint8_t *pci_conf;
 644
 645     if (s->sizearg == NULL)
 646         s->ivshmem_size = 4 << 20; /* 4 MB default */
 647     else {
 648         s->ivshmem_size = ivshmem_get_size(s);
 649     }
 650
 651     register_savevm(&s->dev.qdev, "ivshmem", 0, 0, ivshmem_save, ivshmem_load,
 652                                                                         dev);
 653
 654     /* IRQFD requires MSI */
 655     if (ivshmem_has_feature(s, IVSHMEM_IOEVENTFD) &&
 656         !ivshmem_has_feature(s, IVSHMEM_MSI)) {
 657         fprintf(stderr, "ivshmem: ioeventfd/irqfd requires MSI\n");
 658         exit(1);
 659     }
 660
 661     /* check that role is reasonable */
 662     if (s->role) {
 663         if (strncmp(s->role, "peer", 5) == 0) {
 664             s->role_val = IVSHMEM_PEER;
 665         } else if (strncmp(s->role, "master", 7) == 0) {
 666             s->role_val = IVSHMEM_MASTER;
 667         } else {
 668             fprintf(stderr, "ivshmem: 'role' must be 'peer' or 'master'\n");
 669             exit(1);
 670         }
 671     } else {
 672         s->role_val = IVSHMEM_MASTER; /* default */
 673     }
 674
 675     if (s->role_val == IVSHMEM_PEER) {
 676         error_set(&s->migration_blocker, QERR_DEVICE_FEATURE_BLOCKS_MIGRATION,
 677                   "peer mode", "ivshmem");
 678         migrate_add_blocker(s->migration_blocker);
 679     }
 680
 681     pci_conf = s->dev.config;
 682     pci_conf[PCI_COMMAND] = PCI_COMMAND_IO | PCI_COMMAND_MEMORY;
 683
 684     pci_config_set_interrupt_pin(pci_conf, 1);
 685
 686     s->shm_fd = 0;
 687
 688     memory_region_init_io(&s->ivshmem_mmio, OBJECT(s), &ivshmem_mmio_ops, s,
 689                           "ivshmem-mmio", IVSHMEM_REG_BAR_SIZE);
 690
 691     /* region for registers*/
 692     pci_register_bar(&s->dev, 0, PCI_BASE_ADDRESS_SPACE_MEMORY,
 693                      &s->ivshmem_mmio);
 694
 695     memory_region_init(&s->bar, OBJECT(s), "ivshmem-bar2-container", s->ivshmem_size);
 696     s->ivshmem_attr = PCI_BASE_ADDRESS_SPACE_MEMORY |
 697         PCI_BASE_ADDRESS_MEM_PREFETCH;
 698     if (s->ivshmem_64bit) {
 699         s->ivshmem_attr |= PCI_BASE_ADDRESS_MEM_TYPE_64;
 700     }
 701
 702     if ((s->server_chr != NULL) &&
 703                         (strncmp(s->server_chr->filename, "unix:", 5) == 0)) {
 704         /* if we get a UNIX socket as the parameter we will talk
 705          * to the ivshmem server to receive the memory region */
 706
 707         if (s->shmobj != NULL) {
 708             fprintf(stderr, "WARNING: do not specify both 'chardev' "
 709                                                 "and 'shm' with ivshmem\n");
 710         }
 711
 712         IVSHMEM_DPRINTF("using shared memory server (socket = %s)\n",
 713                                                     s->server_chr->filename);
 714
 715         if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
 716             ivshmem_setup_msi(s);
 717         }
 718
 719         /* we allocate enough space for 16 guests and grow as needed */
 720         s->nb_peers = 16;
 721         s->vm_id = -1;
 722
 723         /* allocate/initialize space for interrupt handling */
 724         s->peers = g_malloc0(s->nb_peers * sizeof(Peer));
 725
 726         pci_register_bar(&s->dev, 2, s->ivshmem_attr, &s->bar);
 727
 728         s->eventfd_chr = g_malloc0(s->vectors * sizeof(CharDriverState *));
 729
 730         qemu_chr_add_handlers(s->server_chr, ivshmem_can_receive, ivshmem_read,
 731                      ivshmem_event, s);
 732     } else {
 733         /* just map the file immediately, we're not using a server */
 734         int fd;
 735
 736         if (s->shmobj == NULL) {
 737             fprintf(stderr, "Must specify 'chardev' or 'shm' to ivshmem\n");
 738             exit(1);
 739         }
 740
 741         IVSHMEM_DPRINTF("using shm_open (shm object = %s)\n", s->shmobj);
 742
 743         /* try opening with O_EXCL and if it succeeds zero the memory
 744          * by truncating to 0 */
 745         if ((fd = shm_open(s->shmobj, O_CREAT|O_RDWR|O_EXCL,
 746                         S_IRWXU|S_IRWXG|S_IRWXO)) > 0) {
 747            /* truncate file to length PCI device's memory */
 748             if (ftruncate(fd, s->ivshmem_size) != 0) {
 749                 fprintf(stderr, "ivshmem: could not truncate shared file\n");
 750             }
 751
 752         } else if ((fd = shm_open(s->shmobj, O_CREAT|O_RDWR,
 753                         S_IRWXU|S_IRWXG|S_IRWXO)) < 0) {
 754             fprintf(stderr, "ivshmem: could not open shared file\n");
 755             exit(-1);
 756
 757         }
 758
 759         if (check_shm_size(s, fd) == -1) {
 760             exit(-1);
 761         }
 762
 763         create_shared_memory_BAR(s, fd);
 764
 765     }
 766
 767     s->dev.config_write = ivshmem_write_config;
 768
 769     return 0;
 770 }
 771
 772 static void pci_ivshmem_uninit(PCIDevice *dev)
 773 {
 774     IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
 775
 776     if (s->migration_blocker) {
 777         migrate_del_blocker(s->migration_blocker);
 778         error_free(s->migration_blocker);
 779     }
 780
 781     memory_region_destroy(&s->ivshmem_mmio);
 782     memory_region_del_subregion(&s->bar, &s->ivshmem);
 783     vmstate_unregister_ram(&s->ivshmem, &s->dev.qdev);
 784     memory_region_destroy(&s->ivshmem);
 785     memory_region_destroy(&s->bar);
 786     unregister_savevm(&dev->qdev, "ivshmem", s);
 787 }
 788
 789 static Property ivshmem_properties[] = {
 790     DEFINE_PROP_CHR("chardev", IVShmemState, server_chr),
 791     DEFINE_PROP_STRING("size", IVShmemState, sizearg),
 792     DEFINE_PROP_UINT32("vectors", IVShmemState, vectors, 1),
 793     DEFINE_PROP_BIT("ioeventfd", IVShmemState, features, IVSHMEM_IOEVENTFD, false),
 794     DEFINE_PROP_BIT("msi", IVShmemState, features, IVSHMEM_MSI, true),
 795     DEFINE_PROP_STRING("shm", IVShmemState, shmobj),
 796     DEFINE_PROP_STRING("role", IVShmemState, role),
 797     DEFINE_PROP_UINT32("use64", IVShmemState, ivshmem_64bit, 1),
 798     DEFINE_PROP_END_OF_LIST(),
 799 };
 800
 801 static void ivshmem_class_init(ObjectClass *klass, void *data)
 802 {
 803     DeviceClass *dc = DEVICE_CLASS(klass);
 804     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
 805
 806     k->init = pci_ivshmem_init;
 807     k->exit = pci_ivshmem_uninit;
 808     k->vendor_id = PCI_VENDOR_ID_IVSHMEM;
 809     k->device_id = PCI_DEVICE_ID_IVSHMEM;
 810     k->class_id = PCI_CLASS_MEMORY_RAM;
 811     dc->reset = ivshmem_reset;
 812     dc->props = ivshmem_properties;
 813 }
 814
 815 static const TypeInfo ivshmem_info = {
 816     .name          = "ivshmem",
 817     .parent        = TYPE_PCI_DEVICE,
 818     .instance_size = sizeof(IVShmemState),
 819     .class_init    = ivshmem_class_init,
 820 };
 821
 822 static void ivshmem_register_types(void)
 823 {
 824     type_register_static(&ivshmem_info);
 825 }
 826
 827 type_init(ivshmem_register_types)