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.h"
  22 #include "msix.h"
  23 #include "kvm.h"
  24 #include "migration.h"
  25 #include "qerror.h"
  26
  27 #include <sys/mman.h>
  28 #include <sys/types.h>
  29
  30 #define IVSHMEM_IOEVENTFD   0
  31 #define IVSHMEM_MSI     1
  32
  33 #define IVSHMEM_PEER    0
  34 #define IVSHMEM_MASTER  1
  35
  36 #define IVSHMEM_REG_BAR_SIZE 0x100
  37
  38 //#define DEBUG_IVSHMEM
  39 #ifdef DEBUG_IVSHMEM
  40 #define IVSHMEM_DPRINTF(fmt, ...)        \
  41     do {printf("IVSHMEM: " fmt, ## __VA_ARGS__); } while (0)
  42 #else
  43 #define IVSHMEM_DPRINTF(fmt, ...)
  44 #endif
  45
  46 typedef struct Peer {
  47     int nb_eventfds;
  48     int *eventfds;
  49 } Peer;
  50
  51 typedef struct EventfdEntry {
  52     PCIDevice *pdev;
  53     int vector;
  54 } EventfdEntry;
  55
  56 typedef struct IVShmemState {
  57     PCIDevice dev;
  58     uint32_t intrmask;
  59     uint32_t intrstatus;
  60     uint32_t doorbell;
  61
  62     CharDriverState **eventfd_chr;
  63     CharDriverState *server_chr;
  64     MemoryRegion ivshmem_mmio;
  65
  66     pcibus_t mmio_addr;
  67     /* We might need to register the BAR before we actually have the memory.
  68      * So prepare a container MemoryRegion for the BAR immediately and
  69      * add a subregion when we have the memory.
  70      */
  71     MemoryRegion bar;
  72     MemoryRegion ivshmem;
  73     MemoryRegion msix_bar;
  74     uint64_t ivshmem_size; /* size of shared memory region */
  75     int shm_fd; /* shared memory file descriptor */
  76
  77     Peer *peers;
  78     int nb_peers; /* how many guests we have space for */
  79     int max_peer; /* maximum numbered peer */
  80
  81     int vm_id;
  82     uint32_t vectors;
  83     uint32_t features;
  84     EventfdEntry *eventfd_table;
  85
  86     Error *migration_blocker;
  87
  88     char * shmobj;
  89     char * sizearg;
  90     char * role;
  91     int role_val;   /* scalar to avoid multiple string comparisons */
  92 } IVShmemState;
  93
  94 /* registers for the Inter-VM shared memory device */
  95 enum ivshmem_registers {
  96     INTRMASK = 0,
  97     INTRSTATUS = 4,
  98     IVPOSITION = 8,
  99     DOORBELL = 12,
 100 };
 101
 102 static inline uint32_t ivshmem_has_feature(IVShmemState *ivs,
 103                                                     unsigned int feature) {
 104     return (ivs->features & (1 << feature));
 105 }
 106
 107 static inline bool is_power_of_two(uint64_t x) {
 108     return (x & (x - 1)) == 0;
 109 }
 110
 111 /* accessing registers - based on rtl8139 */
 112 static void ivshmem_update_irq(IVShmemState *s, int val)
 113 {
 114     int isr;
 115     isr = (s->intrstatus & s->intrmask) & 0xffffffff;
 116
 117     /* don't print ISR resets */
 118     if (isr) {
 119         IVSHMEM_DPRINTF("Set IRQ to %d (%04x %04x)\n",
 120            isr ? 1 : 0, s->intrstatus, s->intrmask);
 121     }
 122
 123     qemu_set_irq(s->dev.irq[0], (isr != 0));
 124 }
 125
 126 static void ivshmem_IntrMask_write(IVShmemState *s, uint32_t val)
 127 {
 128     IVSHMEM_DPRINTF("IntrMask write(w) val = 0x%04x\n", val);
 129
 130     s->intrmask = val;
 131
 132     ivshmem_update_irq(s, val);
 133 }
 134
 135 static uint32_t ivshmem_IntrMask_read(IVShmemState *s)
 136 {
 137     uint32_t ret = s->intrmask;
 138
 139     IVSHMEM_DPRINTF("intrmask read(w) val = 0x%04x\n", ret);
 140
 141     return ret;
 142 }
 143
 144 static void ivshmem_IntrStatus_write(IVShmemState *s, uint32_t val)
 145 {
 146     IVSHMEM_DPRINTF("IntrStatus write(w) val = 0x%04x\n", val);
 147
 148     s->intrstatus = val;
 149
 150     ivshmem_update_irq(s, val);
 151     return;
 152 }
 153
 154 static uint32_t ivshmem_IntrStatus_read(IVShmemState *s)
 155 {
 156     uint32_t ret = s->intrstatus;
 157
 158     /* reading ISR clears all interrupts */
 159     s->intrstatus = 0;
 160
 161     ivshmem_update_irq(s, 0);
 162
 163     return ret;
 164 }
 165
 166 static void ivshmem_io_write(void *opaque, target_phys_addr_t addr,
 167                              uint64_t val, unsigned size)
 168 {
 169     IVShmemState *s = opaque;
 170
 171     uint64_t write_one = 1;
 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("Writing %" PRId64 " to VM %d on vector %d\n",
 198                                                     write_one, dest, vector);
 199                 if (write(s->peers[dest].eventfds[vector],
 200                                                     &(write_one), 8) != 8) {
 201                     IVSHMEM_DPRINTF("error writing to eventfd\n");
 202                 }
 203             }
 204             break;
 205         default:
 206             IVSHMEM_DPRINTF("Invalid VM Doorbell VM %d\n", dest);
 207     }
 208 }
 209
 210 static uint64_t ivshmem_io_read(void *opaque, target_phys_addr_t addr,
 211                                 unsigned size)
 212 {
 213
 214     IVShmemState *s = opaque;
 215     uint32_t ret;
 216
 217     switch (addr)
 218     {
 219         case INTRMASK:
 220             ret = ivshmem_IntrMask_read(s);
 221             break;
 222
 223         case INTRSTATUS:
 224             ret = ivshmem_IntrStatus_read(s);
 225             break;
 226
 227         case IVPOSITION:
 228             /* return my VM ID if the memory is mapped */
 229             if (s->shm_fd > 0) {
 230                 ret = s->vm_id;
 231             } else {
 232                 ret = -1;
 233             }
 234             break;
 235
 236         default:
 237             IVSHMEM_DPRINTF("why are we reading " TARGET_FMT_plx "\n", addr);
 238             ret = 0;
 239     }
 240
 241     return ret;
 242 }
 243
 244 static const MemoryRegionOps ivshmem_mmio_ops = {
 245     .read = ivshmem_io_read,
 246     .write = ivshmem_io_write,
 247     .endianness = DEVICE_NATIVE_ENDIAN,
 248     .impl = {
 249         .min_access_size = 4,
 250         .max_access_size = 4,
 251     },
 252 };
 253
 254 static void ivshmem_receive(void *opaque, const uint8_t *buf, int size)
 255 {
 256     IVShmemState *s = opaque;
 257
 258     ivshmem_IntrStatus_write(s, *buf);
 259
 260     IVSHMEM_DPRINTF("ivshmem_receive 0x%02x\n", *buf);
 261 }
 262
 263 static int ivshmem_can_receive(void * opaque)
 264 {
 265     return 8;
 266 }
 267
 268 static void ivshmem_event(void *opaque, int event)
 269 {
 270     IVSHMEM_DPRINTF("ivshmem_event %d\n", event);
 271 }
 272
 273 static void fake_irqfd(void *opaque, const uint8_t *buf, int size) {
 274
 275     EventfdEntry *entry = opaque;
 276     PCIDevice *pdev = entry->pdev;
 277
 278     IVSHMEM_DPRINTF("interrupt on vector %p %d\n", pdev, entry->vector);
 279     msix_notify(pdev, entry->vector);
 280 }
 281
 282 static CharDriverState* create_eventfd_chr_device(void * opaque, int eventfd,
 283                                                                     int vector)
 284 {
 285     /* create a event character device based on the passed eventfd */
 286     IVShmemState *s = opaque;
 287     CharDriverState * chr;
 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
 296     /* if MSI is supported we need multiple interrupts */
 297     if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
 298         s->eventfd_table[vector].pdev = &s->dev;
 299         s->eventfd_table[vector].vector = vector;
 300
 301         qemu_chr_add_handlers(chr, ivshmem_can_receive, fake_irqfd,
 302                       ivshmem_event, &s->eventfd_table[vector]);
 303     } else {
 304         qemu_chr_add_handlers(chr, ivshmem_can_receive, ivshmem_receive,
 305                       ivshmem_event, s);
 306     }
 307
 308     return chr;
 309
 310 }
 311
 312 static int check_shm_size(IVShmemState *s, int fd) {
 313     /* check that the guest isn't going to try and map more memory than the
 314      * the object has allocated return -1 to indicate error */
 315
 316     struct stat buf;
 317
 318     fstat(fd, &buf);
 319
 320     if (s->ivshmem_size > buf.st_size) {
 321         fprintf(stderr,
 322                 "IVSHMEM ERROR: Requested memory size greater"
 323                 " than shared object size (%" PRIu64 " > %" PRIu64")\n",
 324                 s->ivshmem_size, (uint64_t)buf.st_size);
 325         return -1;
 326     } else {
 327         return 0;
 328     }
 329 }
 330
 331 /* create the shared memory BAR when we are not using the server, so we can
 332  * create the BAR and map the memory immediately */
 333 static void create_shared_memory_BAR(IVShmemState *s, int fd) {
 334
 335     void * ptr;
 336
 337     s->shm_fd = fd;
 338
 339     ptr = mmap(0, s->ivshmem_size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
 340
 341     memory_region_init_ram_ptr(&s->ivshmem, "ivshmem.bar2",
 342                                s->ivshmem_size, ptr);
 343     vmstate_register_ram(&s->ivshmem, &s->dev.qdev);
 344     memory_region_add_subregion(&s->bar, 0, &s->ivshmem);
 345
 346     /* region for shared memory */
 347     pci_register_bar(&s->dev, 2, PCI_BASE_ADDRESS_SPACE_MEMORY, &s->bar);
 348 }
 349
 350 static void close_guest_eventfds(IVShmemState *s, int posn)
 351 {
 352     int i, guest_curr_max;
 353
 354     guest_curr_max = s->peers[posn].nb_eventfds;
 355
 356     for (i = 0; i < guest_curr_max; i++) {
 357         kvm_set_ioeventfd_mmio_long(s->peers[posn].eventfds[i],
 358                     s->mmio_addr + DOORBELL, (posn << 16) | i, 0);
 359         close(s->peers[posn].eventfds[i]);
 360     }
 361
 362     g_free(s->peers[posn].eventfds);
 363     s->peers[posn].nb_eventfds = 0;
 364 }
 365
 366 static void setup_ioeventfds(IVShmemState *s) {
 367
 368     int i, j;
 369
 370     for (i = 0; i <= s->max_peer; i++) {
 371         for (j = 0; j < s->peers[i].nb_eventfds; j++) {
 372             memory_region_add_eventfd(&s->ivshmem_mmio,
 373                                       DOORBELL,
 374                                       4,
 375                                       true,
 376                                       (i << 16) | j,
 377                                       s->peers[i].eventfds[j]);
 378         }
 379     }
 380 }
 381
 382 /* this function increase the dynamic storage need to store data about other
 383  * guests */
 384 static void increase_dynamic_storage(IVShmemState *s, int new_min_size) {
 385
 386     int j, old_nb_alloc;
 387
 388     old_nb_alloc = s->nb_peers;
 389
 390     while (new_min_size >= s->nb_peers)
 391         s->nb_peers = s->nb_peers * 2;
 392
 393     IVSHMEM_DPRINTF("bumping storage to %d guests\n", s->nb_peers);
 394     s->peers = g_realloc(s->peers, s->nb_peers * sizeof(Peer));
 395
 396     /* zero out new pointers */
 397     for (j = old_nb_alloc; j < s->nb_peers; j++) {
 398         s->peers[j].eventfds = NULL;
 399         s->peers[j].nb_eventfds = 0;
 400     }
 401 }
 402
 403 static void ivshmem_read(void *opaque, const uint8_t * buf, int flags)
 404 {
 405     IVShmemState *s = opaque;
 406     int incoming_fd, tmp_fd;
 407     int guest_max_eventfd;
 408     long incoming_posn;
 409
 410     memcpy(&incoming_posn, buf, sizeof(long));
 411     /* pick off s->server_chr->msgfd and store it, posn should accompany msg */
 412     tmp_fd = qemu_chr_fe_get_msgfd(s->server_chr);
 413     IVSHMEM_DPRINTF("posn is %ld, fd is %d\n", incoming_posn, tmp_fd);
 414
 415     /* make sure we have enough space for this guest */
 416     if (incoming_posn >= s->nb_peers) {
 417         increase_dynamic_storage(s, incoming_posn);
 418     }
 419
 420     if (tmp_fd == -1) {
 421         /* if posn is positive and unseen before then this is our posn*/
 422         if ((incoming_posn >= 0) &&
 423                             (s->peers[incoming_posn].eventfds == NULL)) {
 424             /* receive our posn */
 425             s->vm_id = incoming_posn;
 426             return;
 427         } else {
 428             /* otherwise an fd == -1 means an existing guest has gone away */
 429             IVSHMEM_DPRINTF("posn %ld has gone away\n", incoming_posn);
 430             close_guest_eventfds(s, incoming_posn);
 431             return;
 432         }
 433     }
 434
 435     /* because of the implementation of get_msgfd, we need a dup */
 436     incoming_fd = dup(tmp_fd);
 437
 438     if (incoming_fd == -1) {
 439         fprintf(stderr, "could not allocate file descriptor %s\n",
 440                                                             strerror(errno));
 441         return;
 442     }
 443
 444     /* if the position is -1, then it's shared memory region fd */
 445     if (incoming_posn == -1) {
 446
 447         void * map_ptr;
 448
 449         s->max_peer = 0;
 450
 451         if (check_shm_size(s, incoming_fd) == -1) {
 452             exit(-1);
 453         }
 454
 455         /* mmap the region and map into the BAR2 */
 456         map_ptr = mmap(0, s->ivshmem_size, PROT_READ|PROT_WRITE, MAP_SHARED,
 457                                                             incoming_fd, 0);
 458         memory_region_init_ram_ptr(&s->ivshmem,
 459                                    "ivshmem.bar2", s->ivshmem_size, map_ptr);
 460         vmstate_register_ram(&s->ivshmem, &s->dev.qdev);
 461
 462         IVSHMEM_DPRINTF("guest h/w addr = %" PRIu64 ", size = %" PRIu64 "\n",
 463                          s->ivshmem_offset, s->ivshmem_size);
 464
 465         memory_region_add_subregion(&s->bar, 0, &s->ivshmem);
 466
 467         /* only store the fd if it is successfully mapped */
 468         s->shm_fd = incoming_fd;
 469
 470         return;
 471     }
 472
 473     /* each guest has an array of eventfds, and we keep track of how many
 474      * guests for each VM */
 475     guest_max_eventfd = s->peers[incoming_posn].nb_eventfds;
 476
 477     if (guest_max_eventfd == 0) {
 478         /* one eventfd per MSI vector */
 479         s->peers[incoming_posn].eventfds = (int *) g_malloc(s->vectors *
 480                                                                 sizeof(int));
 481     }
 482
 483     /* this is an eventfd for a particular guest VM */
 484     IVSHMEM_DPRINTF("eventfds[%ld][%d] = %d\n", incoming_posn,
 485                                             guest_max_eventfd, incoming_fd);
 486     s->peers[incoming_posn].eventfds[guest_max_eventfd] = incoming_fd;
 487
 488     /* increment count for particular guest */
 489     s->peers[incoming_posn].nb_eventfds++;
 490
 491     /* keep track of the maximum VM ID */
 492     if (incoming_posn > s->max_peer) {
 493         s->max_peer = incoming_posn;
 494     }
 495
 496     if (incoming_posn == s->vm_id) {
 497         s->eventfd_chr[guest_max_eventfd] = create_eventfd_chr_device(s,
 498                    s->peers[s->vm_id].eventfds[guest_max_eventfd],
 499                    guest_max_eventfd);
 500     }
 501
 502     if (ivshmem_has_feature(s, IVSHMEM_IOEVENTFD)) {
 503         if (kvm_set_ioeventfd_mmio_long(incoming_fd, s->mmio_addr + DOORBELL,
 504                         (incoming_posn << 16) | guest_max_eventfd, 1) < 0) {
 505             fprintf(stderr, "ivshmem: ioeventfd not available\n");
 506         }
 507     }
 508
 509     return;
 510 }
 511
 512 static void ivshmem_reset(DeviceState *d)
 513 {
 514     IVShmemState *s = DO_UPCAST(IVShmemState, dev.qdev, d);
 515
 516     s->intrstatus = 0;
 517     return;
 518 }
 519
 520 static uint64_t ivshmem_get_size(IVShmemState * s) {
 521
 522     uint64_t value;
 523     char *ptr;
 524
 525     value = strtoull(s->sizearg, &ptr, 10);
 526     switch (*ptr) {
 527         case 0: case 'M': case 'm':
 528             value <<= 20;
 529             break;
 530         case 'G': case 'g':
 531             value <<= 30;
 532             break;
 533         default:
 534             fprintf(stderr, "qemu: invalid ram size: %s\n", s->sizearg);
 535             exit(1);
 536     }
 537
 538     /* BARs must be a power of 2 */
 539     if (!is_power_of_two(value)) {
 540         fprintf(stderr, "ivshmem: size must be power of 2\n");
 541         exit(1);
 542     }
 543
 544     return value;
 545 }
 546
 547 static void ivshmem_setup_msi(IVShmemState * s) {
 548
 549     int i;
 550
 551     /* allocate the MSI-X vectors */
 552
 553     memory_region_init(&s->msix_bar, "ivshmem-msix", 4096);
 554     if (!msix_init(&s->dev, s->vectors, &s->msix_bar, 1, 0)) {
 555         pci_register_bar(&s->dev, 1, PCI_BASE_ADDRESS_SPACE_MEMORY,
 556                          &s->msix_bar);
 557         IVSHMEM_DPRINTF("msix initialized (%d vectors)\n", s->vectors);
 558     } else {
 559         IVSHMEM_DPRINTF("msix initialization failed\n");
 560         exit(1);
 561     }
 562
 563     /* 'activate' the vectors */
 564     for (i = 0; i < s->vectors; i++) {
 565         msix_vector_use(&s->dev, i);
 566     }
 567
 568     /* allocate Qemu char devices for receiving interrupts */
 569     s->eventfd_table = g_malloc0(s->vectors * sizeof(EventfdEntry));
 570 }
 571
 572 static void ivshmem_save(QEMUFile* f, void *opaque)
 573 {
 574     IVShmemState *proxy = opaque;
 575
 576     IVSHMEM_DPRINTF("ivshmem_save\n");
 577     pci_device_save(&proxy->dev, f);
 578
 579     if (ivshmem_has_feature(proxy, IVSHMEM_MSI)) {
 580         msix_save(&proxy->dev, f);
 581     } else {
 582         qemu_put_be32(f, proxy->intrstatus);
 583         qemu_put_be32(f, proxy->intrmask);
 584     }
 585
 586 }
 587
 588 static int ivshmem_load(QEMUFile* f, void *opaque, int version_id)
 589 {
 590     IVSHMEM_DPRINTF("ivshmem_load\n");
 591
 592     IVShmemState *proxy = opaque;
 593     int ret, i;
 594
 595     if (version_id > 0) {
 596         return -EINVAL;
 597     }
 598
 599     if (proxy->role_val == IVSHMEM_PEER) {
 600         fprintf(stderr, "ivshmem: 'peer' devices are not migratable\n");
 601         return -EINVAL;
 602     }
 603
 604     ret = pci_device_load(&proxy->dev, f);
 605     if (ret) {
 606         return ret;
 607     }
 608
 609     if (ivshmem_has_feature(proxy, IVSHMEM_MSI)) {
 610         msix_load(&proxy->dev, f);
 611         for (i = 0; i < proxy->vectors; i++) {
 612             msix_vector_use(&proxy->dev, i);
 613         }
 614     } else {
 615         proxy->intrstatus = qemu_get_be32(f);
 616         proxy->intrmask = qemu_get_be32(f);
 617     }
 618
 619     return 0;
 620 }
 621
 622 static int pci_ivshmem_init(PCIDevice *dev)
 623 {
 624     IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
 625     uint8_t *pci_conf;
 626
 627     if (s->sizearg == NULL)
 628         s->ivshmem_size = 4 << 20; /* 4 MB default */
 629     else {
 630         s->ivshmem_size = ivshmem_get_size(s);
 631     }
 632
 633     register_savevm(&s->dev.qdev, "ivshmem", 0, 0, ivshmem_save, ivshmem_load,
 634                                                                         dev);
 635
 636     /* IRQFD requires MSI */
 637     if (ivshmem_has_feature(s, IVSHMEM_IOEVENTFD) &&
 638         !ivshmem_has_feature(s, IVSHMEM_MSI)) {
 639         fprintf(stderr, "ivshmem: ioeventfd/irqfd requires MSI\n");
 640         exit(1);
 641     }
 642
 643     /* check that role is reasonable */
 644     if (s->role) {
 645         if (strncmp(s->role, "peer", 5) == 0) {
 646             s->role_val = IVSHMEM_PEER;
 647         } else if (strncmp(s->role, "master", 7) == 0) {
 648             s->role_val = IVSHMEM_MASTER;
 649         } else {
 650             fprintf(stderr, "ivshmem: 'role' must be 'peer' or 'master'\n");
 651             exit(1);
 652         }
 653     } else {
 654         s->role_val = IVSHMEM_MASTER; /* default */
 655     }
 656
 657     if (s->role_val == IVSHMEM_PEER) {
 658         error_set(&s->migration_blocker, QERR_DEVICE_FEATURE_BLOCKS_MIGRATION, "ivshmem", "peer mode");
 659         migrate_add_blocker(s->migration_blocker);
 660     }
 661
 662     pci_conf = s->dev.config;
 663     pci_conf[PCI_COMMAND] = PCI_COMMAND_IO | PCI_COMMAND_MEMORY;
 664
 665     pci_config_set_interrupt_pin(pci_conf, 1);
 666
 667     s->shm_fd = 0;
 668
 669     memory_region_init_io(&s->ivshmem_mmio, &ivshmem_mmio_ops, s,
 670                           "ivshmem-mmio", IVSHMEM_REG_BAR_SIZE);
 671
 672     if (ivshmem_has_feature(s, IVSHMEM_IOEVENTFD)) {
 673         setup_ioeventfds(s);
 674     }
 675
 676     /* region for registers*/
 677     pci_register_bar(&s->dev, 0, PCI_BASE_ADDRESS_SPACE_MEMORY,
 678                      &s->ivshmem_mmio);
 679
 680     memory_region_init(&s->bar, "ivshmem-bar2-container", s->ivshmem_size);
 681
 682     if ((s->server_chr != NULL) &&
 683                         (strncmp(s->server_chr->filename, "unix:", 5) == 0)) {
 684         /* if we get a UNIX socket as the parameter we will talk
 685          * to the ivshmem server to receive the memory region */
 686
 687         if (s->shmobj != NULL) {
 688             fprintf(stderr, "WARNING: do not specify both 'chardev' "
 689                                                 "and 'shm' with ivshmem\n");
 690         }
 691
 692         IVSHMEM_DPRINTF("using shared memory server (socket = %s)\n",
 693                                                     s->server_chr->filename);
 694
 695         if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
 696             ivshmem_setup_msi(s);
 697         }
 698
 699         /* we allocate enough space for 16 guests and grow as needed */
 700         s->nb_peers = 16;
 701         s->vm_id = -1;
 702
 703         /* allocate/initialize space for interrupt handling */
 704         s->peers = g_malloc0(s->nb_peers * sizeof(Peer));
 705
 706         pci_register_bar(&s->dev, 2,
 707                          PCI_BASE_ADDRESS_SPACE_MEMORY, &s->bar);
 708
 709         s->eventfd_chr = g_malloc0(s->vectors * sizeof(CharDriverState *));
 710
 711         qemu_chr_add_handlers(s->server_chr, ivshmem_can_receive, ivshmem_read,
 712                      ivshmem_event, s);
 713     } else {
 714         /* just map the file immediately, we're not using a server */
 715         int fd;
 716
 717         if (s->shmobj == NULL) {
 718             fprintf(stderr, "Must specify 'chardev' or 'shm' to ivshmem\n");
 719         }
 720
 721         IVSHMEM_DPRINTF("using shm_open (shm object = %s)\n", s->shmobj);
 722
 723         /* try opening with O_EXCL and if it succeeds zero the memory
 724          * by truncating to 0 */
 725         if ((fd = shm_open(s->shmobj, O_CREAT|O_RDWR|O_EXCL,
 726                         S_IRWXU|S_IRWXG|S_IRWXO)) > 0) {
 727            /* truncate file to length PCI device's memory */
 728             if (ftruncate(fd, s->ivshmem_size) != 0) {
 729                 fprintf(stderr, "ivshmem: could not truncate shared file\n");
 730             }
 731
 732         } else if ((fd = shm_open(s->shmobj, O_CREAT|O_RDWR,
 733                         S_IRWXU|S_IRWXG|S_IRWXO)) < 0) {
 734             fprintf(stderr, "ivshmem: could not open shared file\n");
 735             exit(-1);
 736
 737         }
 738
 739         if (check_shm_size(s, fd) == -1) {
 740             exit(-1);
 741         }
 742
 743         create_shared_memory_BAR(s, fd);
 744
 745     }
 746
 747     return 0;
 748 }
 749
 750 static int pci_ivshmem_uninit(PCIDevice *dev)
 751 {
 752     IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
 753
 754     if (s->migration_blocker) {
 755         migrate_del_blocker(s->migration_blocker);
 756         error_free(s->migration_blocker);
 757     }
 758
 759     memory_region_destroy(&s->ivshmem_mmio);
 760     memory_region_del_subregion(&s->bar, &s->ivshmem);
 761     vmstate_unregister_ram(&s->ivshmem, &s->dev.qdev);
 762     memory_region_destroy(&s->ivshmem);
 763     memory_region_destroy(&s->bar);
 764     unregister_savevm(&dev->qdev, "ivshmem", s);
 765
 766     return 0;
 767 }
 768
 769 static Property ivshmem_properties[] = {
 770     DEFINE_PROP_CHR("chardev", IVShmemState, server_chr),
 771     DEFINE_PROP_STRING("size", IVShmemState, sizearg),
 772     DEFINE_PROP_UINT32("vectors", IVShmemState, vectors, 1),
 773     DEFINE_PROP_BIT("ioeventfd", IVShmemState, features, IVSHMEM_IOEVENTFD, false),
 774     DEFINE_PROP_BIT("msi", IVShmemState, features, IVSHMEM_MSI, true),
 775     DEFINE_PROP_STRING("shm", IVShmemState, shmobj),
 776     DEFINE_PROP_STRING("role", IVShmemState, role),
 777     DEFINE_PROP_END_OF_LIST(),
 778 };
 779
 780 static void ivshmem_class_init(ObjectClass *klass, void *data)
 781 {
 782     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
 783
 784     k->init = pci_ivshmem_init;
 785     k->exit = pci_ivshmem_uninit;
 786     k->vendor_id = PCI_VENDOR_ID_REDHAT_QUMRANET;
 787     k->device_id = 0x1110;
 788     k->class_id = PCI_CLASS_MEMORY_RAM;
 789 }
 790
 791 static DeviceInfo ivshmem_info = {
 792     .name = "ivshmem",
 793     .size = sizeof(IVShmemState),
 794     .reset = ivshmem_reset,
 795     .props = ivshmem_properties,
 796     .class_init = ivshmem_class_init,
 797 };
 798
 799 static void ivshmem_register_devices(void)
 800 {
 801     pci_qdev_register(&ivshmem_info);
 802 }
 803
 804 device_init(ivshmem_register_devices)