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