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