hw/xen/xen-legacy-backend.c

   1 /*
   2  *  xen backend driver infrastructure
   3  *  (c) 2008 Gerd Hoffmann <kraxel@redhat.com>
   4  *
   5  *  This program is free software; you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation; under version 2 of the License.
   8  *
   9  *  This program is distributed in the hope that it will be useful,
  10  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  *  GNU General Public License for more details.
  13  *
  14  *  You should have received a copy of the GNU General Public License along
  15  *  with this program; if not, see <http://www.gnu.org/licenses/>.
  16  *
  17  *  Contributions after 2012-01-13 are licensed under the terms of the
  18  *  GNU GPL, version 2 or (at your option) any later version.
  19  */
  20
  21 /*
  22  * TODO: add some xenbus / xenstore concepts overview here.
  23  */
  24
  25 #include "qemu/osdep.h"
  26
  27 #include "hw/sysbus.h"
  28 #include "hw/boards.h"
  29 #include "hw/qdev-properties.h"
  30 #include "qemu/log.h"
  31 #include "qemu/main-loop.h"
  32 #include "qapi/error.h"
  33 #include "hw/xen/xen-legacy-backend.h"
  34 #include "hw/xen/xen_pvdev.h"
  35 #include "monitor/qdev.h"
  36
  37 DeviceState *xen_sysdev;
  38 BusState *xen_sysbus;
  39
  40 /* ------------------------------------------------------------- */
  41
  42 /* public */
  43 struct xs_handle *xenstore;
  44 const char *xen_protocol;
  45
  46 /* private */
  47 static bool xen_feature_grant_copy;
  48 static int debug;
  49
  50 int xenstore_write_be_str(struct XenLegacyDevice *xendev, const char *node,
  51                           const char *val)
  52 {
  53     return xenstore_write_str(xendev->be, node, val);
  54 }
  55
  56 int xenstore_write_be_int(struct XenLegacyDevice *xendev, const char *node,
  57                           int ival)
  58 {
  59     return xenstore_write_int(xendev->be, node, ival);
  60 }
  61
  62 int xenstore_write_be_int64(struct XenLegacyDevice *xendev, const char *node,
  63                             int64_t ival)
  64 {
  65     return xenstore_write_int64(xendev->be, node, ival);
  66 }
  67
  68 char *xenstore_read_be_str(struct XenLegacyDevice *xendev, const char *node)
  69 {
  70     return xenstore_read_str(xendev->be, node);
  71 }
  72
  73 int xenstore_read_be_int(struct XenLegacyDevice *xendev, const char *node,
  74                          int *ival)
  75 {
  76     return xenstore_read_int(xendev->be, node, ival);
  77 }
  78
  79 char *xenstore_read_fe_str(struct XenLegacyDevice *xendev, const char *node)
  80 {
  81     return xenstore_read_str(xendev->fe, node);
  82 }
  83
  84 int xenstore_read_fe_int(struct XenLegacyDevice *xendev, const char *node,
  85                          int *ival)
  86 {
  87     return xenstore_read_int(xendev->fe, node, ival);
  88 }
  89
  90 int xenstore_read_fe_uint64(struct XenLegacyDevice *xendev, const char *node,
  91                             uint64_t *uval)
  92 {
  93     return xenstore_read_uint64(xendev->fe, node, uval);
  94 }
  95
  96 /* ------------------------------------------------------------- */
  97
  98 int xen_be_set_state(struct XenLegacyDevice *xendev, enum xenbus_state state)
  99 {
 100     int rc;
 101
 102     rc = xenstore_write_be_int(xendev, "state", state);
 103     if (rc < 0) {
 104         return rc;
 105     }
 106     xen_pv_printf(xendev, 1, "backend state: %s -> %s\n",
 107                   xenbus_strstate(xendev->be_state), xenbus_strstate(state));
 108     xendev->be_state = state;
 109     return 0;
 110 }
 111
 112 void xen_be_set_max_grant_refs(struct XenLegacyDevice *xendev,
 113                                unsigned int nr_refs)
 114 {
 115     assert(xendev->ops->flags & DEVOPS_FLAG_NEED_GNTDEV);
 116
 117     if (xengnttab_set_max_grants(xendev->gnttabdev, nr_refs)) {
 118         xen_pv_printf(xendev, 0, "xengnttab_set_max_grants failed: %s\n",
 119                       strerror(errno));
 120     }
 121 }
 122
 123 void *xen_be_map_grant_refs(struct XenLegacyDevice *xendev, uint32_t *refs,
 124                             unsigned int nr_refs, int prot)
 125 {
 126     void *ptr;
 127
 128     assert(xendev->ops->flags & DEVOPS_FLAG_NEED_GNTDEV);
 129
 130     ptr = xengnttab_map_domain_grant_refs(xendev->gnttabdev, nr_refs,
 131                                           xen_domid, refs, prot);
 132     if (!ptr) {
 133         xen_pv_printf(xendev, 0,
 134                       "xengnttab_map_domain_grant_refs failed: %s\n",
 135                       strerror(errno));
 136     }
 137
 138     return ptr;
 139 }
 140
 141 void xen_be_unmap_grant_refs(struct XenLegacyDevice *xendev, void *ptr,
 142                              unsigned int nr_refs)
 143 {
 144     assert(xendev->ops->flags & DEVOPS_FLAG_NEED_GNTDEV);
 145
 146     if (xengnttab_unmap(xendev->gnttabdev, ptr, nr_refs)) {
 147         xen_pv_printf(xendev, 0, "xengnttab_unmap failed: %s\n",
 148                       strerror(errno));
 149     }
 150 }
 151
 152 static int compat_copy_grant_refs(struct XenLegacyDevice *xendev,
 153                                   bool to_domain,
 154                                   XenGrantCopySegment segs[],
 155                                   unsigned int nr_segs)
 156 {
 157     uint32_t *refs = g_new(uint32_t, nr_segs);
 158     int prot = to_domain ? PROT_WRITE : PROT_READ;
 159     void *pages;
 160     unsigned int i;
 161
 162     for (i = 0; i < nr_segs; i++) {
 163         XenGrantCopySegment *seg = &segs[i];
 164
 165         refs[i] = to_domain ?
 166             seg->dest.foreign.ref : seg->source.foreign.ref;
 167     }
 168
 169     pages = xengnttab_map_domain_grant_refs(xendev->gnttabdev, nr_segs,
 170                                             xen_domid, refs, prot);
 171     if (!pages) {
 172         xen_pv_printf(xendev, 0,
 173                       "xengnttab_map_domain_grant_refs failed: %s\n",
 174                       strerror(errno));
 175         g_free(refs);
 176         return -1;
 177     }
 178
 179     for (i = 0; i < nr_segs; i++) {
 180         XenGrantCopySegment *seg = &segs[i];
 181         void *page = pages + (i * XC_PAGE_SIZE);
 182
 183         if (to_domain) {
 184             memcpy(page + seg->dest.foreign.offset, seg->source.virt,
 185                    seg->len);
 186         } else {
 187             memcpy(seg->dest.virt, page + seg->source.foreign.offset,
 188                    seg->len);
 189         }
 190     }
 191
 192     if (xengnttab_unmap(xendev->gnttabdev, pages, nr_segs)) {
 193         xen_pv_printf(xendev, 0, "xengnttab_unmap failed: %s\n",
 194                       strerror(errno));
 195     }
 196
 197     g_free(refs);
 198     return 0;
 199 }
 200
 201 int xen_be_copy_grant_refs(struct XenLegacyDevice *xendev,
 202                            bool to_domain,
 203                            XenGrantCopySegment segs[],
 204                            unsigned int nr_segs)
 205 {
 206     xengnttab_grant_copy_segment_t *xengnttab_segs;
 207     unsigned int i;
 208     int rc;
 209
 210     assert(xendev->ops->flags & DEVOPS_FLAG_NEED_GNTDEV);
 211
 212     if (!xen_feature_grant_copy) {
 213         return compat_copy_grant_refs(xendev, to_domain, segs, nr_segs);
 214     }
 215
 216     xengnttab_segs = g_new0(xengnttab_grant_copy_segment_t, nr_segs);
 217
 218     for (i = 0; i < nr_segs; i++) {
 219         XenGrantCopySegment *seg = &segs[i];
 220         xengnttab_grant_copy_segment_t *xengnttab_seg = &xengnttab_segs[i];
 221
 222         if (to_domain) {
 223             xengnttab_seg->flags = GNTCOPY_dest_gref;
 224             xengnttab_seg->dest.foreign.domid = xen_domid;
 225             xengnttab_seg->dest.foreign.ref = seg->dest.foreign.ref;
 226             xengnttab_seg->dest.foreign.offset = seg->dest.foreign.offset;
 227             xengnttab_seg->source.virt = seg->source.virt;
 228         } else {
 229             xengnttab_seg->flags = GNTCOPY_source_gref;
 230             xengnttab_seg->source.foreign.domid = xen_domid;
 231             xengnttab_seg->source.foreign.ref = seg->source.foreign.ref;
 232             xengnttab_seg->source.foreign.offset =
 233                 seg->source.foreign.offset;
 234             xengnttab_seg->dest.virt = seg->dest.virt;
 235         }
 236
 237         xengnttab_seg->len = seg->len;
 238     }
 239
 240     rc = xengnttab_grant_copy(xendev->gnttabdev, nr_segs, xengnttab_segs);
 241
 242     if (rc) {
 243         xen_pv_printf(xendev, 0, "xengnttab_copy failed: %s\n",
 244                       strerror(errno));
 245     }
 246
 247     for (i = 0; i < nr_segs; i++) {
 248         xengnttab_grant_copy_segment_t *xengnttab_seg =
 249             &xengnttab_segs[i];
 250
 251         if (xengnttab_seg->status != GNTST_okay) {
 252             xen_pv_printf(xendev, 0, "segment[%u] status: %d\n", i,
 253                           xengnttab_seg->status);
 254             rc = -1;
 255         }
 256     }
 257
 258     g_free(xengnttab_segs);
 259     return rc;
 260 }
 261
 262 /*
 263  * get xen backend device, allocate a new one if it doesn't exist.
 264  */
 265 static struct XenLegacyDevice *xen_be_get_xendev(const char *type, int dom,
 266                                                  int dev,
 267                                                  struct XenDevOps *ops)
 268 {
 269     struct XenLegacyDevice *xendev;
 270
 271     xendev = xen_pv_find_xendev(type, dom, dev);
 272     if (xendev) {
 273         return xendev;
 274     }
 275
 276     /* init new xendev */
 277     xendev = g_malloc0(ops->size);
 278     object_initialize(&xendev->qdev, ops->size, TYPE_XENBACKEND);
 279     OBJECT(xendev)->free = g_free;
 280     qdev_set_id(DEVICE(xendev), g_strdup_printf("xen-%s-%d", type, dev));
 281     qdev_realize(DEVICE(xendev), xen_sysbus, &error_fatal);
 282     object_unref(OBJECT(xendev));
 283
 284     xendev->type  = type;
 285     xendev->dom   = dom;
 286     xendev->dev   = dev;
 287     xendev->ops   = ops;
 288
 289     snprintf(xendev->be, sizeof(xendev->be), "backend/%s/%d/%d",
 290              xendev->type, xendev->dom, xendev->dev);
 291     snprintf(xendev->name, sizeof(xendev->name), "%s-%d",
 292              xendev->type, xendev->dev);
 293
 294     xendev->debug      = debug;
 295     xendev->local_port = -1;
 296
 297     xendev->evtchndev = xenevtchn_open(NULL, 0);
 298     if (xendev->evtchndev == NULL) {
 299         xen_pv_printf(NULL, 0, "can't open evtchn device\n");
 300         qdev_unplug(DEVICE(xendev), NULL);
 301         return NULL;
 302     }
 303     qemu_set_cloexec(xenevtchn_fd(xendev->evtchndev));
 304
 305     xen_pv_insert_xendev(xendev);
 306
 307     if (xendev->ops->alloc) {
 308         xendev->ops->alloc(xendev);
 309     }
 310
 311     return xendev;
 312 }
 313
 314
 315 /*
 316  * Sync internal data structures on xenstore updates.
 317  * Node specifies the changed field.  node = NULL means
 318  * update all fields (used for initialization).
 319  */
 320 static void xen_be_backend_changed(struct XenLegacyDevice *xendev,
 321                                    const char *node)
 322 {
 323     if (node == NULL  ||  strcmp(node, "online") == 0) {
 324         if (xenstore_read_be_int(xendev, "online", &xendev->online) == -1) {
 325             xendev->online = 0;
 326         }
 327     }
 328
 329     if (node) {
 330         xen_pv_printf(xendev, 2, "backend update: %s\n", node);
 331         if (xendev->ops->backend_changed) {
 332             xendev->ops->backend_changed(xendev, node);
 333         }
 334     }
 335 }
 336
 337 static void xen_be_frontend_changed(struct XenLegacyDevice *xendev,
 338                                     const char *node)
 339 {
 340     int fe_state;
 341
 342     if (node == NULL  ||  strcmp(node, "state") == 0) {
 343         if (xenstore_read_fe_int(xendev, "state", &fe_state) == -1) {
 344             fe_state = XenbusStateUnknown;
 345         }
 346         if (xendev->fe_state != fe_state) {
 347             xen_pv_printf(xendev, 1, "frontend state: %s -> %s\n",
 348                           xenbus_strstate(xendev->fe_state),
 349                           xenbus_strstate(fe_state));
 350         }
 351         xendev->fe_state = fe_state;
 352     }
 353     if (node == NULL  ||  strcmp(node, "protocol") == 0) {
 354         g_free(xendev->protocol);
 355         xendev->protocol = xenstore_read_fe_str(xendev, "protocol");
 356         if (xendev->protocol) {
 357             xen_pv_printf(xendev, 1, "frontend protocol: %s\n",
 358                           xendev->protocol);
 359         }
 360     }
 361
 362     if (node) {
 363         xen_pv_printf(xendev, 2, "frontend update: %s\n", node);
 364         if (xendev->ops->frontend_changed) {
 365             xendev->ops->frontend_changed(xendev, node);
 366         }
 367     }
 368 }
 369
 370 /* ------------------------------------------------------------- */
 371 /* Check for possible state transitions and perform them.        */
 372
 373 /*
 374  * Initial xendev setup.  Read frontend path, register watch for it.
 375  * Should succeed once xend finished setting up the backend device.
 376  *
 377  * Also sets initial state (-> Initializing) when done.  Which
 378  * only affects the xendev->be_state variable as xenbus should
 379  * already be put into that state by xend.
 380  */
 381 static int xen_be_try_setup(struct XenLegacyDevice *xendev)
 382 {
 383     char token[XEN_BUFSIZE];
 384     int be_state;
 385
 386     if (xenstore_read_be_int(xendev, "state", &be_state) == -1) {
 387         xen_pv_printf(xendev, 0, "reading backend state failed\n");
 388         return -1;
 389     }
 390
 391     if (be_state != XenbusStateInitialising) {
 392         xen_pv_printf(xendev, 0, "initial backend state is wrong (%s)\n",
 393                       xenbus_strstate(be_state));
 394         return -1;
 395     }
 396
 397     xendev->fe = xenstore_read_be_str(xendev, "frontend");
 398     if (xendev->fe == NULL) {
 399         xen_pv_printf(xendev, 0, "reading frontend path failed\n");
 400         return -1;
 401     }
 402
 403     /* setup frontend watch */
 404     snprintf(token, sizeof(token), "fe:%p", xendev);
 405     if (!xs_watch(xenstore, xendev->fe, token)) {
 406         xen_pv_printf(xendev, 0, "watching frontend path (%s) failed\n",
 407                       xendev->fe);
 408         return -1;
 409     }
 410     xen_be_set_state(xendev, XenbusStateInitialising);
 411
 412     xen_be_backend_changed(xendev, NULL);
 413     xen_be_frontend_changed(xendev, NULL);
 414     return 0;
 415 }
 416
 417 /*
 418  * Try initialize xendev.  Prepare everything the backend can do
 419  * without synchronizing with the frontend.  Fakes hotplug-status.  No
 420  * hotplug involved here because this is about userspace drivers, thus
 421  * there are kernel backend devices which could invoke hotplug.
 422  *
 423  * Goes to InitWait on success.
 424  */
 425 static int xen_be_try_init(struct XenLegacyDevice *xendev)
 426 {
 427     int rc = 0;
 428
 429     if (!xendev->online) {
 430         xen_pv_printf(xendev, 1, "not online\n");
 431         return -1;
 432     }
 433
 434     if (xendev->ops->init) {
 435         rc = xendev->ops->init(xendev);
 436     }
 437     if (rc != 0) {
 438         xen_pv_printf(xendev, 1, "init() failed\n");
 439         return rc;
 440     }
 441
 442     xenstore_write_be_str(xendev, "hotplug-status", "connected");
 443     xen_be_set_state(xendev, XenbusStateInitWait);
 444     return 0;
 445 }
 446
 447 /*
 448  * Try to initialise xendev.  Depends on the frontend being ready
 449  * for it (shared ring and evtchn info in xenstore, state being
 450  * Initialised or Connected).
 451  *
 452  * Goes to Connected on success.
 453  */
 454 static int xen_be_try_initialise(struct XenLegacyDevice *xendev)
 455 {
 456     int rc = 0;
 457
 458     if (xendev->fe_state != XenbusStateInitialised  &&
 459         xendev->fe_state != XenbusStateConnected) {
 460         if (xendev->ops->flags & DEVOPS_FLAG_IGNORE_STATE) {
 461             xen_pv_printf(xendev, 2, "frontend not ready, ignoring\n");
 462         } else {
 463             xen_pv_printf(xendev, 2, "frontend not ready (yet)\n");
 464             return -1;
 465         }
 466     }
 467
 468     if (xendev->ops->flags & DEVOPS_FLAG_NEED_GNTDEV) {
 469         xendev->gnttabdev = xengnttab_open(NULL, 0);
 470         if (xendev->gnttabdev == NULL) {
 471             xen_pv_printf(NULL, 0, "can't open gnttab device\n");
 472             return -1;
 473         }
 474     } else {
 475         xendev->gnttabdev = NULL;
 476     }
 477
 478     if (xendev->ops->initialise) {
 479         rc = xendev->ops->initialise(xendev);
 480     }
 481     if (rc != 0) {
 482         xen_pv_printf(xendev, 0, "initialise() failed\n");
 483         return rc;
 484     }
 485
 486     xen_be_set_state(xendev, XenbusStateConnected);
 487     return 0;
 488 }
 489
 490 /*
 491  * Try to let xendev know that it is connected.  Depends on the
 492  * frontend being Connected.  Note that this may be called more
 493  * than once since the backend state is not modified.
 494  */
 495 static void xen_be_try_connected(struct XenLegacyDevice *xendev)
 496 {
 497     if (!xendev->ops->connected) {
 498         return;
 499     }
 500
 501     if (xendev->fe_state != XenbusStateConnected) {
 502         if (xendev->ops->flags & DEVOPS_FLAG_IGNORE_STATE) {
 503             xen_pv_printf(xendev, 2, "frontend not ready, ignoring\n");
 504         } else {
 505             xen_pv_printf(xendev, 2, "frontend not ready (yet)\n");
 506             return;
 507         }
 508     }
 509
 510     xendev->ops->connected(xendev);
 511 }
 512
 513 /*
 514  * Teardown connection.
 515  *
 516  * Goes to Closed when done.
 517  */
 518 static void xen_be_disconnect(struct XenLegacyDevice *xendev,
 519                               enum xenbus_state state)
 520 {
 521     if (xendev->be_state != XenbusStateClosing &&
 522         xendev->be_state != XenbusStateClosed  &&
 523         xendev->ops->disconnect) {
 524         xendev->ops->disconnect(xendev);
 525     }
 526     if (xendev->gnttabdev) {
 527         xengnttab_close(xendev->gnttabdev);
 528         xendev->gnttabdev = NULL;
 529     }
 530     if (xendev->be_state != state) {
 531         xen_be_set_state(xendev, state);
 532     }
 533 }
 534
 535 /*
 536  * Try to reset xendev, for reconnection by another frontend instance.
 537  */
 538 static int xen_be_try_reset(struct XenLegacyDevice *xendev)
 539 {
 540     if (xendev->fe_state != XenbusStateInitialising) {
 541         return -1;
 542     }
 543
 544     xen_pv_printf(xendev, 1, "device reset (for re-connect)\n");
 545     xen_be_set_state(xendev, XenbusStateInitialising);
 546     return 0;
 547 }
 548
 549 /*
 550  * state change dispatcher function
 551  */
 552 void xen_be_check_state(struct XenLegacyDevice *xendev)
 553 {
 554     int rc = 0;
 555
 556     /* frontend may request shutdown from almost anywhere */
 557     if (xendev->fe_state == XenbusStateClosing ||
 558         xendev->fe_state == XenbusStateClosed) {
 559         xen_be_disconnect(xendev, xendev->fe_state);
 560         return;
 561     }
 562
 563     /* check for possible backend state transitions */
 564     for (;;) {
 565         switch (xendev->be_state) {
 566         case XenbusStateUnknown:
 567             rc = xen_be_try_setup(xendev);
 568             break;
 569         case XenbusStateInitialising:
 570             rc = xen_be_try_init(xendev);
 571             break;
 572         case XenbusStateInitWait:
 573             rc = xen_be_try_initialise(xendev);
 574             break;
 575         case XenbusStateConnected:
 576             /* xendev->be_state doesn't change */
 577             xen_be_try_connected(xendev);
 578             rc = -1;
 579             break;
 580         case XenbusStateClosed:
 581             rc = xen_be_try_reset(xendev);
 582             break;
 583         default:
 584             rc = -1;
 585         }
 586         if (rc != 0) {
 587             break;
 588         }
 589     }
 590 }
 591
 592 /* ------------------------------------------------------------- */
 593
 594 static int xenstore_scan(const char *type, int dom, struct XenDevOps *ops)
 595 {
 596     struct XenLegacyDevice *xendev;
 597     char path[XEN_BUFSIZE], token[XEN_BUFSIZE];
 598     char **dev = NULL;
 599     unsigned int cdev, j;
 600
 601     /* setup watch */
 602     snprintf(token, sizeof(token), "be:%p:%d:%p", type, dom, ops);
 603     snprintf(path, sizeof(path), "backend/%s/%d", type, dom);
 604     if (!xs_watch(xenstore, path, token)) {
 605         xen_pv_printf(NULL, 0, "xen be: watching backend path (%s) failed\n",
 606                       path);
 607         return -1;
 608     }
 609
 610     /* look for backends */
 611     dev = xs_directory(xenstore, 0, path, &cdev);
 612     if (!dev) {
 613         return 0;
 614     }
 615     for (j = 0; j < cdev; j++) {
 616         xendev = xen_be_get_xendev(type, dom, atoi(dev[j]), ops);
 617         if (xendev == NULL) {
 618             continue;
 619         }
 620         xen_be_check_state(xendev);
 621     }
 622     free(dev);
 623     return 0;
 624 }
 625
 626 void xenstore_update_be(char *watch, char *type, int dom,
 627                         struct XenDevOps *ops)
 628 {
 629     struct XenLegacyDevice *xendev;
 630     char path[XEN_BUFSIZE], *bepath;
 631     unsigned int len, dev;
 632
 633     len = snprintf(path, sizeof(path), "backend/%s/%d", type, dom);
 634     if (strncmp(path, watch, len) != 0) {
 635         return;
 636     }
 637     if (sscanf(watch + len, "/%u/%255s", &dev, path) != 2) {
 638         strcpy(path, "");
 639         if (sscanf(watch + len, "/%u", &dev) != 1) {
 640             dev = -1;
 641         }
 642     }
 643     if (dev == -1) {
 644         return;
 645     }
 646
 647     xendev = xen_be_get_xendev(type, dom, dev, ops);
 648     if (xendev != NULL) {
 649         bepath = xs_read(xenstore, 0, xendev->be, &len);
 650         if (bepath == NULL) {
 651             xen_pv_del_xendev(xendev);
 652         } else {
 653             free(bepath);
 654             xen_be_backend_changed(xendev, path);
 655             xen_be_check_state(xendev);
 656         }
 657     }
 658 }
 659
 660 void xenstore_update_fe(char *watch, struct XenLegacyDevice *xendev)
 661 {
 662     char *node;
 663     unsigned int len;
 664
 665     len = strlen(xendev->fe);
 666     if (strncmp(xendev->fe, watch, len) != 0) {
 667         return;
 668     }
 669     if (watch[len] != '/') {
 670         return;
 671     }
 672     node = watch + len + 1;
 673
 674     xen_be_frontend_changed(xendev, node);
 675     xen_be_check_state(xendev);
 676 }
 677 /* -------------------------------------------------------------------- */
 678
 679 int xen_be_init(void)
 680 {
 681     xengnttab_handle *gnttabdev;
 682
 683     xenstore = xs_daemon_open();
 684     if (!xenstore) {
 685         xen_pv_printf(NULL, 0, "can't connect to xenstored\n");
 686         return -1;
 687     }
 688
 689     qemu_set_fd_handler(xs_fileno(xenstore), xenstore_update, NULL, NULL);
 690
 691     if (xen_xc == NULL || xen_fmem == NULL) {
 692         /* Check if xen_init() have been called */
 693         goto err;
 694     }
 695
 696     gnttabdev = xengnttab_open(NULL, 0);
 697     if (gnttabdev != NULL) {
 698         if (xengnttab_grant_copy(gnttabdev, 0, NULL) == 0) {
 699             xen_feature_grant_copy = true;
 700         }
 701         xengnttab_close(gnttabdev);
 702     }
 703
 704     xen_sysdev = qdev_new(TYPE_XENSYSDEV);
 705     sysbus_realize_and_unref(SYS_BUS_DEVICE(xen_sysdev), &error_fatal);
 706     xen_sysbus = qbus_create(TYPE_XENSYSBUS, xen_sysdev, "xen-sysbus");
 707     qbus_set_bus_hotplug_handler(xen_sysbus);
 708
 709     return 0;
 710
 711 err:
 712     qemu_set_fd_handler(xs_fileno(xenstore), NULL, NULL, NULL);
 713     xs_daemon_close(xenstore);
 714     xenstore = NULL;
 715
 716     return -1;
 717 }
 718
 719 static void xen_set_dynamic_sysbus(void)
 720 {
 721     Object *machine = qdev_get_machine();
 722     ObjectClass *oc = object_get_class(machine);
 723     MachineClass *mc = MACHINE_CLASS(oc);
 724
 725     machine_class_allow_dynamic_sysbus_dev(mc, TYPE_XENSYSDEV);
 726 }
 727
 728 int xen_be_register(const char *type, struct XenDevOps *ops)
 729 {
 730     char path[50];
 731     int rc;
 732
 733     if (ops->backend_register) {
 734         rc = ops->backend_register();
 735         if (rc) {
 736             return rc;
 737         }
 738     }
 739
 740     snprintf(path, sizeof(path), "device-model/%u/backends/%s", xen_domid,
 741              type);
 742     xenstore_mkdir(path, XS_PERM_NONE);
 743
 744     return xenstore_scan(type, xen_domid, ops);
 745 }
 746
 747 void xen_be_register_common(void)
 748 {
 749     xen_set_dynamic_sysbus();
 750
 751     xen_be_register("console", &xen_console_ops);
 752     xen_be_register("vkbd", &xen_kbdmouse_ops);
 753 #ifdef CONFIG_VIRTFS
 754     xen_be_register("9pfs", &xen_9pfs_ops);
 755 #endif
 756 #ifdef CONFIG_USB_LIBUSB
 757     xen_be_register("qusb", &xen_usb_ops);
 758 #endif
 759 }
 760
 761 int xen_be_bind_evtchn(struct XenLegacyDevice *xendev)
 762 {
 763     if (xendev->local_port != -1) {
 764         return 0;
 765     }
 766     xendev->local_port = xenevtchn_bind_interdomain
 767         (xendev->evtchndev, xendev->dom, xendev->remote_port);
 768     if (xendev->local_port == -1) {
 769         xen_pv_printf(xendev, 0, "xenevtchn_bind_interdomain failed\n");
 770         return -1;
 771     }
 772     xen_pv_printf(xendev, 2, "bind evtchn port %d\n", xendev->local_port);
 773     qemu_set_fd_handler(xenevtchn_fd(xendev->evtchndev),
 774                         xen_pv_evtchn_event, NULL, xendev);
 775     return 0;
 776 }
 777
 778
 779 static Property xendev_properties[] = {
 780     DEFINE_PROP_END_OF_LIST(),
 781 };
 782
 783 static void xendev_class_init(ObjectClass *klass, void *data)
 784 {
 785     DeviceClass *dc = DEVICE_CLASS(klass);
 786
 787     device_class_set_props(dc, xendev_properties);
 788     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
 789     /* xen-backend devices can be plugged/unplugged dynamically */
 790     dc->user_creatable = true;
 791     dc->bus_type = TYPE_XENSYSBUS;
 792 }
 793
 794 static const TypeInfo xendev_type_info = {
 795     .name          = TYPE_XENBACKEND,
 796     .parent        = TYPE_DEVICE,
 797     .class_init    = xendev_class_init,
 798     .instance_size = sizeof(struct XenLegacyDevice),
 799 };
 800
 801 static void xen_sysbus_class_init(ObjectClass *klass, void *data)
 802 {
 803     HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass);
 804
 805     hc->unplug = qdev_simple_device_unplug_cb;
 806 }
 807
 808 static const TypeInfo xensysbus_info = {
 809     .name       = TYPE_XENSYSBUS,
 810     .parent     = TYPE_BUS,
 811     .class_init = xen_sysbus_class_init,
 812     .interfaces = (InterfaceInfo[]) {
 813         { TYPE_HOTPLUG_HANDLER },
 814         { }
 815     }
 816 };
 817
 818 static Property xen_sysdev_properties[] = {
 819     {/* end of property list */},
 820 };
 821
 822 static void xen_sysdev_class_init(ObjectClass *klass, void *data)
 823 {
 824     DeviceClass *dc = DEVICE_CLASS(klass);
 825
 826     device_class_set_props(dc, xen_sysdev_properties);
 827 }
 828
 829 static const TypeInfo xensysdev_info = {
 830     .name          = TYPE_XENSYSDEV,
 831     .parent        = TYPE_SYS_BUS_DEVICE,
 832     .instance_size = sizeof(SysBusDevice),
 833     .class_init    = xen_sysdev_class_init,
 834 };
 835
 836 static void xenbe_register_types(void)
 837 {
 838     type_register_static(&xensysbus_info);
 839     type_register_static(&xensysdev_info);
 840     type_register_static(&xendev_type_info);
 841 }
 842
 843 type_init(xenbe_register_types)