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     uint64_t ivshmem_size; /* size of shared memory region */
  74     int shm_fd; /* shared memory file descriptor */
  75
  76     Peer *peers;
  77     int nb_peers; /* how many guests we have space for */
  78     int max_peer; /* maximum numbered peer */
  79
  80     int vm_id;
  81     uint32_t vectors;
  82     uint32_t features;
  83     EventfdEntry *eventfd_table;
  84
  85     Error *migration_blocker;
  86
  87     char * shmobj;
  88     char * sizearg;
  89     char * role;
  90     int role_val;   /* scalar to avoid multiple string comparisons */
  91 } IVShmemState;
  92
  93 /* registers for the Inter-VM shared memory device */
  94 enum ivshmem_registers {
  95     INTRMASK = 0,
  96     INTRSTATUS = 4,
  97     IVPOSITION = 8,
  98     DOORBELL = 12,
  99 };
 100
 101 static inline uint32_t ivshmem_has_feature(IVShmemState *ivs,
 102                                                     unsigned int feature) {
 103     return (ivs->features & (1 << feature));
 104 }
 105
 106 static inline bool is_power_of_two(uint64_t x) {
 107     return (x & (x - 1)) == 0;
 108 }
 109
 110 /* accessing registers - based on rtl8139 */
 111 static void ivshmem_update_irq(IVShmemState *s, int val)
 112 {
 113     int isr;
 114     isr = (s->intrstatus & s->intrmask) & 0xffffffff;
 115
 116     /* don't print ISR resets */
 117     if (isr) {
 118         IVSHMEM_DPRINTF("Set IRQ to %d (%04x %04x)\n",
 119            isr ? 1 : 0, s->intrstatus, s->intrmask);
 120     }
 121
 122     qemu_set_irq(s->dev.irq[0], (isr != 0));
 123 }
 124
 125 static void ivshmem_IntrMask_write(IVShmemState *s, uint32_t val)
 126 {
 127     IVSHMEM_DPRINTF("IntrMask write(w) val = 0x%04x\n", val);
 128
 129     s->intrmask = val;
 130
 131     ivshmem_update_irq(s, val);
 132 }
 133
 134 static uint32_t ivshmem_IntrMask_read(IVShmemState *s)
 135 {
 136     uint32_t ret = s->intrmask;
 137
 138     IVSHMEM_DPRINTF("intrmask read(w) val = 0x%04x\n", ret);
 139
 140     return ret;
 141 }
 142
 143 static void ivshmem_IntrStatus_write(IVShmemState *s, uint32_t val)
 144 {
 145     IVSHMEM_DPRINTF("IntrStatus write(w) val = 0x%04x\n", val);
 146
 147     s->intrstatus = val;
 148
 149     ivshmem_update_irq(s, val);
 150     return;
 151 }
 152
 153 static uint32_t ivshmem_IntrStatus_read(IVShmemState *s)
 154 {
 155     uint32_t ret = s->intrstatus;
 156
 157     /* reading ISR clears all interrupts */
 158     s->intrstatus = 0;
 159
 160     ivshmem_update_irq(s, 0);
 161
 162     return ret;
 163 }
 164
 165 static void ivshmem_io_write(void *opaque, target_phys_addr_t addr,
 166                              uint64_t val, unsigned size)
 167 {
 168     IVShmemState *s = opaque;
 169
 170     uint64_t write_one = 1;
 171     uint16_t dest = val >> 16;
 172     uint16_t vector = val & 0xff;
 173
 174     addr &= 0xfc;
 175
 176     IVSHMEM_DPRINTF("writing to addr " TARGET_FMT_plx "\n", addr);
 177     switch (addr)
 178     {
 179         case INTRMASK:
 180             ivshmem_IntrMask_write(s, val);
 181             break;
 182
 183         case INTRSTATUS:
 184             ivshmem_IntrStatus_write(s, val);
 185             break;
 186
 187         case DOORBELL:
 188             /* check that dest VM ID is reasonable */
 189             if (dest > s->max_peer) {
 190                 IVSHMEM_DPRINTF("Invalid destination VM ID (%d)\n", dest);
 191                 break;
 192             }
 193
 194             /* check doorbell range */
 195             if (vector < s->peers[dest].nb_eventfds) {
 196                 IVSHMEM_DPRINTF("Writing %" PRId64 " to VM %d on vector %d\n",
 197                                                     write_one, dest, vector);
 198                 if (write(s->peers[dest].eventfds[vector],
 199                                                     &(write_one), 8) != 8) {
 200                     IVSHMEM_DPRINTF("error writing to eventfd\n");
 201                 }
 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, target_phys_addr_t 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, int eventfd,
 282                                                                     int vector)
 283 {
 284     /* create a event character device based on the passed eventfd */
 285     IVShmemState *s = opaque;
 286     CharDriverState * chr;
 287
 288     chr = qemu_chr_open_eventfd(eventfd);
 289
 290     if (chr == NULL) {
 291         fprintf(stderr, "creating eventfd for eventfd %d failed\n", eventfd);
 292         exit(-1);
 293     }
 294
 295     /* if MSI is supported we need multiple interrupts */
 296     if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
 297         s->eventfd_table[vector].pdev = &s->dev;
 298         s->eventfd_table[vector].vector = vector;
 299
 300         qemu_chr_add_handlers(chr, ivshmem_can_receive, fake_irqfd,
 301                       ivshmem_event, &s->eventfd_table[vector]);
 302     } else {
 303         qemu_chr_add_handlers(chr, ivshmem_can_receive, ivshmem_receive,
 304                       ivshmem_event, s);
 305     }
 306
 307     return chr;
 308
 309 }
 310
 311 static int check_shm_size(IVShmemState *s, int fd) {
 312     /* check that the guest isn't going to try and map more memory than the
 313      * the object has allocated return -1 to indicate error */
 314
 315     struct stat buf;
 316
 317     fstat(fd, &buf);
 318
 319     if (s->ivshmem_size > buf.st_size) {
 320         fprintf(stderr,
 321                 "IVSHMEM ERROR: Requested memory size greater"
 322                 " than shared object size (%" PRIu64 " > %" PRIu64")\n",
 323                 s->ivshmem_size, (uint64_t)buf.st_size);
 324         return -1;
 325     } else {
 326         return 0;
 327     }
 328 }
 329
 330 /* create the shared memory BAR when we are not using the server, so we can
 331  * create the BAR and map the memory immediately */
 332 static void create_shared_memory_BAR(IVShmemState *s, int fd) {
 333
 334     void * ptr;
 335
 336     s->shm_fd = fd;
 337
 338     ptr = mmap(0, s->ivshmem_size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
 339
 340     memory_region_init_ram_ptr(&s->ivshmem, "ivshmem.bar2",
 341                                s->ivshmem_size, ptr);
 342     vmstate_register_ram(&s->ivshmem, &s->dev.qdev);
 343     memory_region_add_subregion(&s->bar, 0, &s->ivshmem);
 344
 345     /* region for shared memory */
 346     pci_register_bar(&s->dev, 2, PCI_BASE_ADDRESS_SPACE_MEMORY, &s->bar);
 347 }
 348
 349 static void close_guest_eventfds(IVShmemState *s, int posn)
 350 {
 351     int i, guest_curr_max;
 352
 353     guest_curr_max = s->peers[posn].nb_eventfds;
 354
 355     for (i = 0; i < guest_curr_max; i++) {
 356         kvm_set_ioeventfd_mmio(s->peers[posn].eventfds[i],
 357                     s->mmio_addr + DOORBELL, (posn << 16) | i, 0, 4);
 358         close(s->peers[posn].eventfds[i]);
 359     }
 360
 361     g_free(s->peers[posn].eventfds);
 362     s->peers[posn].nb_eventfds = 0;
 363 }
 364
 365 static void setup_ioeventfds(IVShmemState *s) {
 366
 367     int i, j;
 368
 369     for (i = 0; i <= s->max_peer; i++) {
 370         for (j = 0; j < s->peers[i].nb_eventfds; j++) {
 371             memory_region_add_eventfd(&s->ivshmem_mmio,
 372                                       DOORBELL,
 373                                       4,
 374                                       true,
 375                                       (i << 16) | j,
 376                                       s->peers[i].eventfds[j]);
 377         }
 378     }
 379 }
 380
 381 /* this function increase the dynamic storage need to store data about other
 382  * guests */
 383 static void increase_dynamic_storage(IVShmemState *s, int new_min_size) {
 384
 385     int j, old_nb_alloc;
 386
 387     old_nb_alloc = s->nb_peers;
 388
 389     while (new_min_size >= s->nb_peers)
 390         s->nb_peers = s->nb_peers * 2;
 391
 392     IVSHMEM_DPRINTF("bumping storage to %d guests\n", s->nb_peers);
 393     s->peers = g_realloc(s->peers, s->nb_peers * sizeof(Peer));
 394
 395     /* zero out new pointers */
 396     for (j = old_nb_alloc; j < s->nb_peers; j++) {
 397         s->peers[j].eventfds = NULL;
 398         s->peers[j].nb_eventfds = 0;
 399     }
 400 }
 401
 402 static void ivshmem_read(void *opaque, const uint8_t * buf, int flags)
 403 {
 404     IVShmemState *s = opaque;
 405     int incoming_fd, tmp_fd;
 406     int guest_max_eventfd;
 407     long incoming_posn;
 408
 409     memcpy(&incoming_posn, buf, sizeof(long));
 410     /* pick off s->server_chr->msgfd and store it, posn should accompany msg */
 411     tmp_fd = qemu_chr_fe_get_msgfd(s->server_chr);
 412     IVSHMEM_DPRINTF("posn is %ld, fd is %d\n", incoming_posn, tmp_fd);
 413
 414     /* make sure we have enough space for this guest */
 415     if (incoming_posn >= s->nb_peers) {
 416         increase_dynamic_storage(s, incoming_posn);
 417     }
 418
 419     if (tmp_fd == -1) {
 420         /* if posn is positive and unseen before then this is our posn*/
 421         if ((incoming_posn >= 0) &&
 422                             (s->peers[incoming_posn].eventfds == NULL)) {
 423             /* receive our posn */
 424             s->vm_id = incoming_posn;
 425             return;
 426         } else {
 427             /* otherwise an fd == -1 means an existing guest has gone away */
 428             IVSHMEM_DPRINTF("posn %ld has gone away\n", incoming_posn);
 429             close_guest_eventfds(s, incoming_posn);
 430             return;
 431         }
 432     }
 433
 434     /* because of the implementation of get_msgfd, we need a dup */
 435     incoming_fd = dup(tmp_fd);
 436
 437     if (incoming_fd == -1) {
 438         fprintf(stderr, "could not allocate file descriptor %s\n",
 439                                                             strerror(errno));
 440         return;
 441     }
 442
 443     /* if the position is -1, then it's shared memory region fd */
 444     if (incoming_posn == -1) {
 445
 446         void * map_ptr;
 447
 448         s->max_peer = 0;
 449
 450         if (check_shm_size(s, incoming_fd) == -1) {
 451             exit(-1);
 452         }
 453
 454         /* mmap the region and map into the BAR2 */
 455         map_ptr = mmap(0, s->ivshmem_size, PROT_READ|PROT_WRITE, MAP_SHARED,
 456                                                             incoming_fd, 0);
 457         memory_region_init_ram_ptr(&s->ivshmem,
 458                                    "ivshmem.bar2", s->ivshmem_size, map_ptr);
 459         vmstate_register_ram(&s->ivshmem, &s->dev.qdev);
 460
 461         IVSHMEM_DPRINTF("guest h/w addr = %" PRIu64 ", size = %" PRIu64 "\n",
 462                          s->ivshmem_offset, s->ivshmem_size);
 463
 464         memory_region_add_subregion(&s->bar, 0, &s->ivshmem);
 465
 466         /* only store the fd if it is successfully mapped */
 467         s->shm_fd = incoming_fd;
 468
 469         return;
 470     }
 471
 472     /* each guest has an array of eventfds, and we keep track of how many
 473      * guests for each VM */
 474     guest_max_eventfd = s->peers[incoming_posn].nb_eventfds;
 475
 476     if (guest_max_eventfd == 0) {
 477         /* one eventfd per MSI vector */
 478         s->peers[incoming_posn].eventfds = (int *) g_malloc(s->vectors *
 479                                                                 sizeof(int));
 480     }
 481
 482     /* this is an eventfd for a particular guest VM */
 483     IVSHMEM_DPRINTF("eventfds[%ld][%d] = %d\n", incoming_posn,
 484                                             guest_max_eventfd, incoming_fd);
 485     s->peers[incoming_posn].eventfds[guest_max_eventfd] = incoming_fd;
 486
 487     /* increment count for particular guest */
 488     s->peers[incoming_posn].nb_eventfds++;
 489
 490     /* keep track of the maximum VM ID */
 491     if (incoming_posn > s->max_peer) {
 492         s->max_peer = incoming_posn;
 493     }
 494
 495     if (incoming_posn == s->vm_id) {
 496         s->eventfd_chr[guest_max_eventfd] = create_eventfd_chr_device(s,
 497                    s->peers[s->vm_id].eventfds[guest_max_eventfd],
 498                    guest_max_eventfd);
 499     }
 500
 501     if (ivshmem_has_feature(s, IVSHMEM_IOEVENTFD)) {
 502         if (kvm_set_ioeventfd_mmio(incoming_fd, s->mmio_addr + DOORBELL,
 503                         (incoming_posn << 16) | guest_max_eventfd, 1, 4) < 0) {
 504             fprintf(stderr, "ivshmem: ioeventfd not available\n");
 505         }
 506     }
 507
 508     return;
 509 }
 510
 511 /* Select the MSI-X vectors used by device.
 512  * ivshmem maps events to vectors statically, so
 513  * we just enable all vectors on init and after reset. */
 514 static void ivshmem_use_msix(IVShmemState * s)
 515 {
 516     int i;
 517
 518     if (!msix_present(&s->dev)) {
 519         return;
 520     }
 521
 522     for (i = 0; i < s->vectors; i++) {
 523         msix_vector_use(&s->dev, i);
 524     }
 525 }
 526
 527 static void ivshmem_reset(DeviceState *d)
 528 {
 529     IVShmemState *s = DO_UPCAST(IVShmemState, dev.qdev, d);
 530
 531     s->intrstatus = 0;
 532     ivshmem_use_msix(s);
 533     return;
 534 }
 535
 536 static uint64_t ivshmem_get_size(IVShmemState * s) {
 537
 538     uint64_t value;
 539     char *ptr;
 540
 541     value = strtoull(s->sizearg, &ptr, 10);
 542     switch (*ptr) {
 543         case 0: case 'M': case 'm':
 544             value <<= 20;
 545             break;
 546         case 'G': case 'g':
 547             value <<= 30;
 548             break;
 549         default:
 550             fprintf(stderr, "qemu: invalid ram size: %s\n", s->sizearg);
 551             exit(1);
 552     }
 553
 554     /* BARs must be a power of 2 */
 555     if (!is_power_of_two(value)) {
 556         fprintf(stderr, "ivshmem: size must be power of 2\n");
 557         exit(1);
 558     }
 559
 560     return value;
 561 }
 562
 563 static void ivshmem_setup_msi(IVShmemState * s)
 564 {
 565     if (msix_init_exclusive_bar(&s->dev, s->vectors, 1)) {
 566         IVSHMEM_DPRINTF("msix initialization failed\n");
 567         exit(1);
 568     }
 569
 570     IVSHMEM_DPRINTF("msix initialized (%d vectors)\n", s->vectors);
 571
 572     /* allocate QEMU char devices for receiving interrupts */
 573     s->eventfd_table = g_malloc0(s->vectors * sizeof(EventfdEntry));
 574
 575     ivshmem_use_msix(s);
 576 }
 577
 578 static void ivshmem_save(QEMUFile* f, void *opaque)
 579 {
 580     IVShmemState *proxy = opaque;
 581
 582     IVSHMEM_DPRINTF("ivshmem_save\n");
 583     pci_device_save(&proxy->dev, f);
 584
 585     if (ivshmem_has_feature(proxy, IVSHMEM_MSI)) {
 586         msix_save(&proxy->dev, f);
 587     } else {
 588         qemu_put_be32(f, proxy->intrstatus);
 589         qemu_put_be32(f, proxy->intrmask);
 590     }
 591
 592 }
 593
 594 static int ivshmem_load(QEMUFile* f, void *opaque, int version_id)
 595 {
 596     IVSHMEM_DPRINTF("ivshmem_load\n");
 597
 598     IVShmemState *proxy = opaque;
 599     int ret;
 600
 601     if (version_id > 0) {
 602         return -EINVAL;
 603     }
 604
 605     if (proxy->role_val == IVSHMEM_PEER) {
 606         fprintf(stderr, "ivshmem: 'peer' devices are not migratable\n");
 607         return -EINVAL;
 608     }
 609
 610     ret = pci_device_load(&proxy->dev, f);
 611     if (ret) {
 612         return ret;
 613     }
 614
 615     if (ivshmem_has_feature(proxy, IVSHMEM_MSI)) {
 616         msix_load(&proxy->dev, f);
 617         ivshmem_use_msix(proxy);
 618     } else {
 619         proxy->intrstatus = qemu_get_be32(f);
 620         proxy->intrmask = qemu_get_be32(f);
 621     }
 622
 623     return 0;
 624 }
 625
 626 static void ivshmem_write_config(PCIDevice *pci_dev, uint32_t address,
 627                                  uint32_t val, int len)
 628 {
 629     pci_default_write_config(pci_dev, address, val, len);
 630     msix_write_config(pci_dev, address, val, len);
 631 }
 632
 633 static int pci_ivshmem_init(PCIDevice *dev)
 634 {
 635     IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
 636     uint8_t *pci_conf;
 637
 638     if (s->sizearg == NULL)
 639         s->ivshmem_size = 4 << 20; /* 4 MB default */
 640     else {
 641         s->ivshmem_size = ivshmem_get_size(s);
 642     }
 643
 644     register_savevm(&s->dev.qdev, "ivshmem", 0, 0, ivshmem_save, ivshmem_load,
 645                                                                         dev);
 646
 647     /* IRQFD requires MSI */
 648     if (ivshmem_has_feature(s, IVSHMEM_IOEVENTFD) &&
 649         !ivshmem_has_feature(s, IVSHMEM_MSI)) {
 650         fprintf(stderr, "ivshmem: ioeventfd/irqfd requires MSI\n");
 651         exit(1);
 652     }
 653
 654     /* check that role is reasonable */
 655     if (s->role) {
 656         if (strncmp(s->role, "peer", 5) == 0) {
 657             s->role_val = IVSHMEM_PEER;
 658         } else if (strncmp(s->role, "master", 7) == 0) {
 659             s->role_val = IVSHMEM_MASTER;
 660         } else {
 661             fprintf(stderr, "ivshmem: 'role' must be 'peer' or 'master'\n");
 662             exit(1);
 663         }
 664     } else {
 665         s->role_val = IVSHMEM_MASTER; /* default */
 666     }
 667
 668     if (s->role_val == IVSHMEM_PEER) {
 669         error_set(&s->migration_blocker, QERR_DEVICE_FEATURE_BLOCKS_MIGRATION, "ivshmem", "peer mode");
 670         migrate_add_blocker(s->migration_blocker);
 671     }
 672
 673     pci_conf = s->dev.config;
 674     pci_conf[PCI_COMMAND] = PCI_COMMAND_IO | PCI_COMMAND_MEMORY;
 675
 676     pci_config_set_interrupt_pin(pci_conf, 1);
 677
 678     s->shm_fd = 0;
 679
 680     memory_region_init_io(&s->ivshmem_mmio, &ivshmem_mmio_ops, s,
 681                           "ivshmem-mmio", IVSHMEM_REG_BAR_SIZE);
 682
 683     if (ivshmem_has_feature(s, IVSHMEM_IOEVENTFD)) {
 684         setup_ioeventfds(s);
 685     }
 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
 693     if ((s->server_chr != NULL) &&
 694                         (strncmp(s->server_chr->filename, "unix:", 5) == 0)) {
 695         /* if we get a UNIX socket as the parameter we will talk
 696          * to the ivshmem server to receive the memory region */
 697
 698         if (s->shmobj != NULL) {
 699             fprintf(stderr, "WARNING: do not specify both 'chardev' "
 700                                                 "and 'shm' with ivshmem\n");
 701         }
 702
 703         IVSHMEM_DPRINTF("using shared memory server (socket = %s)\n",
 704                                                     s->server_chr->filename);
 705
 706         if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
 707             ivshmem_setup_msi(s);
 708         }
 709
 710         /* we allocate enough space for 16 guests and grow as needed */
 711         s->nb_peers = 16;
 712         s->vm_id = -1;
 713
 714         /* allocate/initialize space for interrupt handling */
 715         s->peers = g_malloc0(s->nb_peers * sizeof(Peer));
 716
 717         pci_register_bar(&s->dev, 2,
 718                          PCI_BASE_ADDRESS_SPACE_MEMORY, &s->bar);
 719
 720         s->eventfd_chr = g_malloc0(s->vectors * sizeof(CharDriverState *));
 721
 722         qemu_chr_add_handlers(s->server_chr, ivshmem_can_receive, ivshmem_read,
 723                      ivshmem_event, s);
 724     } else {
 725         /* just map the file immediately, we're not using a server */
 726         int fd;
 727
 728         if (s->shmobj == NULL) {
 729             fprintf(stderr, "Must specify 'chardev' or 'shm' to ivshmem\n");
 730         }
 731
 732         IVSHMEM_DPRINTF("using shm_open (shm object = %s)\n", s->shmobj);
 733
 734         /* try opening with O_EXCL and if it succeeds zero the memory
 735          * by truncating to 0 */
 736         if ((fd = shm_open(s->shmobj, O_CREAT|O_RDWR|O_EXCL,
 737                         S_IRWXU|S_IRWXG|S_IRWXO)) > 0) {
 738            /* truncate file to length PCI device's memory */
 739             if (ftruncate(fd, s->ivshmem_size) != 0) {
 740                 fprintf(stderr, "ivshmem: could not truncate shared file\n");
 741             }
 742
 743         } else if ((fd = shm_open(s->shmobj, O_CREAT|O_RDWR,
 744                         S_IRWXU|S_IRWXG|S_IRWXO)) < 0) {
 745             fprintf(stderr, "ivshmem: could not open shared file\n");
 746             exit(-1);
 747
 748         }
 749
 750         if (check_shm_size(s, fd) == -1) {
 751             exit(-1);
 752         }
 753
 754         create_shared_memory_BAR(s, fd);
 755
 756     }
 757
 758     s->dev.config_write = ivshmem_write_config;
 759
 760     return 0;
 761 }
 762
 763 static int pci_ivshmem_uninit(PCIDevice *dev)
 764 {
 765     IVShmemState *s = DO_UPCAST(IVShmemState, dev, dev);
 766
 767     if (s->migration_blocker) {
 768         migrate_del_blocker(s->migration_blocker);
 769         error_free(s->migration_blocker);
 770     }
 771
 772     memory_region_destroy(&s->ivshmem_mmio);
 773     memory_region_del_subregion(&s->bar, &s->ivshmem);
 774     vmstate_unregister_ram(&s->ivshmem, &s->dev.qdev);
 775     memory_region_destroy(&s->ivshmem);
 776     memory_region_destroy(&s->bar);
 777     unregister_savevm(&dev->qdev, "ivshmem", s);
 778
 779     return 0;
 780 }
 781
 782 static Property ivshmem_properties[] = {
 783     DEFINE_PROP_CHR("chardev", IVShmemState, server_chr),
 784     DEFINE_PROP_STRING("size", IVShmemState, sizearg),
 785     DEFINE_PROP_UINT32("vectors", IVShmemState, vectors, 1),
 786     DEFINE_PROP_BIT("ioeventfd", IVShmemState, features, IVSHMEM_IOEVENTFD, false),
 787     DEFINE_PROP_BIT("msi", IVShmemState, features, IVSHMEM_MSI, true),
 788     DEFINE_PROP_STRING("shm", IVShmemState, shmobj),
 789     DEFINE_PROP_STRING("role", IVShmemState, role),
 790     DEFINE_PROP_END_OF_LIST(),
 791 };
 792
 793 static void ivshmem_class_init(ObjectClass *klass, void *data)
 794 {
 795     DeviceClass *dc = DEVICE_CLASS(klass);
 796     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
 797
 798     k->init = pci_ivshmem_init;
 799     k->exit = pci_ivshmem_uninit;
 800     k->vendor_id = PCI_VENDOR_ID_REDHAT_QUMRANET;
 801     k->device_id = 0x1110;
 802     k->class_id = PCI_CLASS_MEMORY_RAM;
 803     dc->reset = ivshmem_reset;
 804     dc->props = ivshmem_properties;
 805 }
 806
 807 static TypeInfo ivshmem_info = {
 808     .name          = "ivshmem",
 809     .parent        = TYPE_PCI_DEVICE,
 810     .instance_size = sizeof(IVShmemState),
 811     .class_init    = ivshmem_class_init,
 812 };
 813
 814 static void ivshmem_register_types(void)
 815 {
 816     type_register_static(&ivshmem_info);
 817 }
 818
 819 type_init(ivshmem_register_types)