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_parent_bus(DEVICE(xendev), xen_sysbus);
 282     qdev_set_id(DEVICE(xendev), g_strdup_printf("xen-%s-%d", type, dev));
 283     qdev_init_nofail(DEVICE(xendev));
 284     object_unref(OBJECT(xendev));
 285
 286     xendev->type  = type;
 287     xendev->dom   = dom;
 288     xendev->dev   = dev;
 289     xendev->ops   = ops;
 290
 291     snprintf(xendev->be, sizeof(xendev->be), "backend/%s/%d/%d",
 292              xendev->type, xendev->dom, xendev->dev);
 293     snprintf(xendev->name, sizeof(xendev->name), "%s-%d",
 294              xendev->type, xendev->dev);
 295
 296     xendev->debug      = debug;
 297     xendev->local_port = -1;
 298
 299     xendev->evtchndev = xenevtchn_open(NULL, 0);
 300     if (xendev->evtchndev == NULL) {
 301         xen_pv_printf(NULL, 0, "can't open evtchn device\n");
 302         qdev_unplug(DEVICE(xendev), NULL);
 303         return NULL;
 304     }
 305     qemu_set_cloexec(xenevtchn_fd(xendev->evtchndev));
 306
 307     xen_pv_insert_xendev(xendev);
 308
 309     if (xendev->ops->alloc) {
 310         xendev->ops->alloc(xendev);
 311     }
 312
 313     return xendev;
 314 }
 315
 316
 317 /*
 318  * Sync internal data structures on xenstore updates.
 319  * Node specifies the changed field.  node = NULL means
 320  * update all fields (used for initialization).
 321  */
 322 static void xen_be_backend_changed(struct XenLegacyDevice *xendev,
 323                                    const char *node)
 324 {
 325     if (node == NULL  ||  strcmp(node, "online") == 0) {
 326         if (xenstore_read_be_int(xendev, "online", &xendev->online) == -1) {
 327             xendev->online = 0;
 328         }
 329     }
 330
 331     if (node) {
 332         xen_pv_printf(xendev, 2, "backend update: %s\n", node);
 333         if (xendev->ops->backend_changed) {
 334             xendev->ops->backend_changed(xendev, node);
 335         }
 336     }
 337 }
 338
 339 static void xen_be_frontend_changed(struct XenLegacyDevice *xendev,
 340                                     const char *node)
 341 {
 342     int fe_state;
 343
 344     if (node == NULL  ||  strcmp(node, "state") == 0) {
 345         if (xenstore_read_fe_int(xendev, "state", &fe_state) == -1) {
 346             fe_state = XenbusStateUnknown;
 347         }
 348         if (xendev->fe_state != fe_state) {
 349             xen_pv_printf(xendev, 1, "frontend state: %s -> %s\n",
 350                           xenbus_strstate(xendev->fe_state),
 351                           xenbus_strstate(fe_state));
 352         }
 353         xendev->fe_state = fe_state;
 354     }
 355     if (node == NULL  ||  strcmp(node, "protocol") == 0) {
 356         g_free(xendev->protocol);
 357         xendev->protocol = xenstore_read_fe_str(xendev, "protocol");
 358         if (xendev->protocol) {
 359             xen_pv_printf(xendev, 1, "frontend protocol: %s\n",
 360                           xendev->protocol);
 361         }
 362     }
 363
 364     if (node) {
 365         xen_pv_printf(xendev, 2, "frontend update: %s\n", node);
 366         if (xendev->ops->frontend_changed) {
 367             xendev->ops->frontend_changed(xendev, node);
 368         }
 369     }
 370 }
 371
 372 /* ------------------------------------------------------------- */
 373 /* Check for possible state transitions and perform them.        */
 374
 375 /*
 376  * Initial xendev setup.  Read frontend path, register watch for it.
 377  * Should succeed once xend finished setting up the backend device.
 378  *
 379  * Also sets initial state (-> Initializing) when done.  Which
 380  * only affects the xendev->be_state variable as xenbus should
 381  * already be put into that state by xend.
 382  */
 383 static int xen_be_try_setup(struct XenLegacyDevice *xendev)
 384 {
 385     char token[XEN_BUFSIZE];
 386     int be_state;
 387
 388     if (xenstore_read_be_int(xendev, "state", &be_state) == -1) {
 389         xen_pv_printf(xendev, 0, "reading backend state failed\n");
 390         return -1;
 391     }
 392
 393     if (be_state != XenbusStateInitialising) {
 394         xen_pv_printf(xendev, 0, "initial backend state is wrong (%s)\n",
 395                       xenbus_strstate(be_state));
 396         return -1;
 397     }
 398
 399     xendev->fe = xenstore_read_be_str(xendev, "frontend");
 400     if (xendev->fe == NULL) {
 401         xen_pv_printf(xendev, 0, "reading frontend path failed\n");
 402         return -1;
 403     }
 404
 405     /* setup frontend watch */
 406     snprintf(token, sizeof(token), "fe:%p", xendev);
 407     if (!xs_watch(xenstore, xendev->fe, token)) {
 408         xen_pv_printf(xendev, 0, "watching frontend path (%s) failed\n",
 409                       xendev->fe);
 410         return -1;
 411     }
 412     xen_be_set_state(xendev, XenbusStateInitialising);
 413
 414     xen_be_backend_changed(xendev, NULL);
 415     xen_be_frontend_changed(xendev, NULL);
 416     return 0;
 417 }
 418
 419 /*
 420  * Try initialize xendev.  Prepare everything the backend can do
 421  * without synchronizing with the frontend.  Fakes hotplug-status.  No
 422  * hotplug involved here because this is about userspace drivers, thus
 423  * there are kernel backend devices which could invoke hotplug.
 424  *
 425  * Goes to InitWait on success.
 426  */
 427 static int xen_be_try_init(struct XenLegacyDevice *xendev)
 428 {
 429     int rc = 0;
 430
 431     if (!xendev->online) {
 432         xen_pv_printf(xendev, 1, "not online\n");
 433         return -1;
 434     }
 435
 436     if (xendev->ops->init) {
 437         rc = xendev->ops->init(xendev);
 438     }
 439     if (rc != 0) {
 440         xen_pv_printf(xendev, 1, "init() failed\n");
 441         return rc;
 442     }
 443
 444     xenstore_write_be_str(xendev, "hotplug-status", "connected");
 445     xen_be_set_state(xendev, XenbusStateInitWait);
 446     return 0;
 447 }
 448
 449 /*
 450  * Try to initialise xendev.  Depends on the frontend being ready
 451  * for it (shared ring and evtchn info in xenstore, state being
 452  * Initialised or Connected).
 453  *
 454  * Goes to Connected on success.
 455  */
 456 static int xen_be_try_initialise(struct XenLegacyDevice *xendev)
 457 {
 458     int rc = 0;
 459
 460     if (xendev->fe_state != XenbusStateInitialised  &&
 461         xendev->fe_state != XenbusStateConnected) {
 462         if (xendev->ops->flags & DEVOPS_FLAG_IGNORE_STATE) {
 463             xen_pv_printf(xendev, 2, "frontend not ready, ignoring\n");
 464         } else {
 465             xen_pv_printf(xendev, 2, "frontend not ready (yet)\n");
 466             return -1;
 467         }
 468     }
 469
 470     if (xendev->ops->flags & DEVOPS_FLAG_NEED_GNTDEV) {
 471         xendev->gnttabdev = xengnttab_open(NULL, 0);
 472         if (xendev->gnttabdev == NULL) {
 473             xen_pv_printf(NULL, 0, "can't open gnttab device\n");
 474             return -1;
 475         }
 476     } else {
 477         xendev->gnttabdev = NULL;
 478     }
 479
 480     if (xendev->ops->initialise) {
 481         rc = xendev->ops->initialise(xendev);
 482     }
 483     if (rc != 0) {
 484         xen_pv_printf(xendev, 0, "initialise() failed\n");
 485         return rc;
 486     }
 487
 488     xen_be_set_state(xendev, XenbusStateConnected);
 489     return 0;
 490 }
 491
 492 /*
 493  * Try to let xendev know that it is connected.  Depends on the
 494  * frontend being Connected.  Note that this may be called more
 495  * than once since the backend state is not modified.
 496  */
 497 static void xen_be_try_connected(struct XenLegacyDevice *xendev)
 498 {
 499     if (!xendev->ops->connected) {
 500         return;
 501     }
 502
 503     if (xendev->fe_state != XenbusStateConnected) {
 504         if (xendev->ops->flags & DEVOPS_FLAG_IGNORE_STATE) {
 505             xen_pv_printf(xendev, 2, "frontend not ready, ignoring\n");
 506         } else {
 507             xen_pv_printf(xendev, 2, "frontend not ready (yet)\n");
 508             return;
 509         }
 510     }
 511
 512     xendev->ops->connected(xendev);
 513 }
 514
 515 /*
 516  * Teardown connection.
 517  *
 518  * Goes to Closed when done.
 519  */
 520 static void xen_be_disconnect(struct XenLegacyDevice *xendev,
 521                               enum xenbus_state state)
 522 {
 523     if (xendev->be_state != XenbusStateClosing &&
 524         xendev->be_state != XenbusStateClosed  &&
 525         xendev->ops->disconnect) {
 526         xendev->ops->disconnect(xendev);
 527     }
 528     if (xendev->gnttabdev) {
 529         xengnttab_close(xendev->gnttabdev);
 530         xendev->gnttabdev = NULL;
 531     }
 532     if (xendev->be_state != state) {
 533         xen_be_set_state(xendev, state);
 534     }
 535 }
 536
 537 /*
 538  * Try to reset xendev, for reconnection by another frontend instance.
 539  */
 540 static int xen_be_try_reset(struct XenLegacyDevice *xendev)
 541 {
 542     if (xendev->fe_state != XenbusStateInitialising) {
 543         return -1;
 544     }
 545
 546     xen_pv_printf(xendev, 1, "device reset (for re-connect)\n");
 547     xen_be_set_state(xendev, XenbusStateInitialising);
 548     return 0;
 549 }
 550
 551 /*
 552  * state change dispatcher function
 553  */
 554 void xen_be_check_state(struct XenLegacyDevice *xendev)
 555 {
 556     int rc = 0;
 557
 558     /* frontend may request shutdown from almost anywhere */
 559     if (xendev->fe_state == XenbusStateClosing ||
 560         xendev->fe_state == XenbusStateClosed) {
 561         xen_be_disconnect(xendev, xendev->fe_state);
 562         return;
 563     }
 564
 565     /* check for possible backend state transitions */
 566     for (;;) {
 567         switch (xendev->be_state) {
 568         case XenbusStateUnknown:
 569             rc = xen_be_try_setup(xendev);
 570             break;
 571         case XenbusStateInitialising:
 572             rc = xen_be_try_init(xendev);
 573             break;
 574         case XenbusStateInitWait:
 575             rc = xen_be_try_initialise(xendev);
 576             break;
 577         case XenbusStateConnected:
 578             /* xendev->be_state doesn't change */
 579             xen_be_try_connected(xendev);
 580             rc = -1;
 581             break;
 582         case XenbusStateClosed:
 583             rc = xen_be_try_reset(xendev);
 584             break;
 585         default:
 586             rc = -1;
 587         }
 588         if (rc != 0) {
 589             break;
 590         }
 591     }
 592 }
 593
 594 /* ------------------------------------------------------------- */
 595
 596 static int xenstore_scan(const char *type, int dom, struct XenDevOps *ops)
 597 {
 598     struct XenLegacyDevice *xendev;
 599     char path[XEN_BUFSIZE], token[XEN_BUFSIZE];
 600     char **dev = NULL;
 601     unsigned int cdev, j;
 602
 603     /* setup watch */
 604     snprintf(token, sizeof(token), "be:%p:%d:%p", type, dom, ops);
 605     snprintf(path, sizeof(path), "backend/%s/%d", type, dom);
 606     if (!xs_watch(xenstore, path, token)) {
 607         xen_pv_printf(NULL, 0, "xen be: watching backend path (%s) failed\n",
 608                       path);
 609         return -1;
 610     }
 611
 612     /* look for backends */
 613     dev = xs_directory(xenstore, 0, path, &cdev);
 614     if (!dev) {
 615         return 0;
 616     }
 617     for (j = 0; j < cdev; j++) {
 618         xendev = xen_be_get_xendev(type, dom, atoi(dev[j]), ops);
 619         if (xendev == NULL) {
 620             continue;
 621         }
 622         xen_be_check_state(xendev);
 623     }
 624     free(dev);
 625     return 0;
 626 }
 627
 628 void xenstore_update_be(char *watch, char *type, int dom,
 629                         struct XenDevOps *ops)
 630 {
 631     struct XenLegacyDevice *xendev;
 632     char path[XEN_BUFSIZE], *bepath;
 633     unsigned int len, dev;
 634
 635     len = snprintf(path, sizeof(path), "backend/%s/%d", type, dom);
 636     if (strncmp(path, watch, len) != 0) {
 637         return;
 638     }
 639     if (sscanf(watch + len, "/%u/%255s", &dev, path) != 2) {
 640         strcpy(path, "");
 641         if (sscanf(watch + len, "/%u", &dev) != 1) {
 642             dev = -1;
 643         }
 644     }
 645     if (dev == -1) {
 646         return;
 647     }
 648
 649     xendev = xen_be_get_xendev(type, dom, dev, ops);
 650     if (xendev != NULL) {
 651         bepath = xs_read(xenstore, 0, xendev->be, &len);
 652         if (bepath == NULL) {
 653             xen_pv_del_xendev(xendev);
 654         } else {
 655             free(bepath);
 656             xen_be_backend_changed(xendev, path);
 657             xen_be_check_state(xendev);
 658         }
 659     }
 660 }
 661
 662 void xenstore_update_fe(char *watch, struct XenLegacyDevice *xendev)
 663 {
 664     char *node;
 665     unsigned int len;
 666
 667     len = strlen(xendev->fe);
 668     if (strncmp(xendev->fe, watch, len) != 0) {
 669         return;
 670     }
 671     if (watch[len] != '/') {
 672         return;
 673     }
 674     node = watch + len + 1;
 675
 676     xen_be_frontend_changed(xendev, node);
 677     xen_be_check_state(xendev);
 678 }
 679 /* -------------------------------------------------------------------- */
 680
 681 int xen_be_init(void)
 682 {
 683     xengnttab_handle *gnttabdev;
 684
 685     xenstore = xs_daemon_open();
 686     if (!xenstore) {
 687         xen_pv_printf(NULL, 0, "can't connect to xenstored\n");
 688         return -1;
 689     }
 690
 691     qemu_set_fd_handler(xs_fileno(xenstore), xenstore_update, NULL, NULL);
 692
 693     if (xen_xc == NULL || xen_fmem == NULL) {
 694         /* Check if xen_init() have been called */
 695         goto err;
 696     }
 697
 698     gnttabdev = xengnttab_open(NULL, 0);
 699     if (gnttabdev != NULL) {
 700         if (xengnttab_grant_copy(gnttabdev, 0, NULL) == 0) {
 701             xen_feature_grant_copy = true;
 702         }
 703         xengnttab_close(gnttabdev);
 704     }
 705
 706     xen_sysdev = qdev_create(NULL, TYPE_XENSYSDEV);
 707     qdev_init_nofail(xen_sysdev);
 708     xen_sysbus = qbus_create(TYPE_XENSYSBUS, DEVICE(xen_sysdev), "xen-sysbus");
 709     qbus_set_bus_hotplug_handler(xen_sysbus, &error_abort);
 710
 711     return 0;
 712
 713 err:
 714     qemu_set_fd_handler(xs_fileno(xenstore), NULL, NULL, NULL);
 715     xs_daemon_close(xenstore);
 716     xenstore = NULL;
 717
 718     return -1;
 719 }
 720
 721 static void xen_set_dynamic_sysbus(void)
 722 {
 723     Object *machine = qdev_get_machine();
 724     ObjectClass *oc = object_get_class(machine);
 725     MachineClass *mc = MACHINE_CLASS(oc);
 726
 727     machine_class_allow_dynamic_sysbus_dev(mc, TYPE_XENSYSDEV);
 728 }
 729
 730 int xen_be_register(const char *type, struct XenDevOps *ops)
 731 {
 732     char path[50];
 733     int rc;
 734
 735     if (ops->backend_register) {
 736         rc = ops->backend_register();
 737         if (rc) {
 738             return rc;
 739         }
 740     }
 741
 742     snprintf(path, sizeof(path), "device-model/%u/backends/%s", xen_domid,
 743              type);
 744     xenstore_mkdir(path, XS_PERM_NONE);
 745
 746     return xenstore_scan(type, xen_domid, ops);
 747 }
 748
 749 void xen_be_register_common(void)
 750 {
 751     xen_set_dynamic_sysbus();
 752
 753     xen_be_register("console", &xen_console_ops);
 754     xen_be_register("vkbd", &xen_kbdmouse_ops);
 755 #ifdef CONFIG_VIRTFS
 756     xen_be_register("9pfs", &xen_9pfs_ops);
 757 #endif
 758 #ifdef CONFIG_USB_LIBUSB
 759     xen_be_register("qusb", &xen_usb_ops);
 760 #endif
 761 }
 762
 763 int xen_be_bind_evtchn(struct XenLegacyDevice *xendev)
 764 {
 765     if (xendev->local_port != -1) {
 766         return 0;
 767     }
 768     xendev->local_port = xenevtchn_bind_interdomain
 769         (xendev->evtchndev, xendev->dom, xendev->remote_port);
 770     if (xendev->local_port == -1) {
 771         xen_pv_printf(xendev, 0, "xenevtchn_bind_interdomain failed\n");
 772         return -1;
 773     }
 774     xen_pv_printf(xendev, 2, "bind evtchn port %d\n", xendev->local_port);
 775     qemu_set_fd_handler(xenevtchn_fd(xendev->evtchndev),
 776                         xen_pv_evtchn_event, NULL, xendev);
 777     return 0;
 778 }
 779
 780
 781 static Property xendev_properties[] = {
 782     DEFINE_PROP_END_OF_LIST(),
 783 };
 784
 785 static void xendev_class_init(ObjectClass *klass, void *data)
 786 {
 787     DeviceClass *dc = DEVICE_CLASS(klass);
 788
 789     dc->props = xendev_properties;
 790     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
 791     /* xen-backend devices can be plugged/unplugged dynamically */
 792     dc->user_creatable = true;
 793 }
 794
 795 static const TypeInfo xendev_type_info = {
 796     .name          = TYPE_XENBACKEND,
 797     .parent        = TYPE_XENSYSDEV,
 798     .class_init    = xendev_class_init,
 799     .instance_size = sizeof(struct XenLegacyDevice),
 800 };
 801
 802 static void xen_sysbus_class_init(ObjectClass *klass, void *data)
 803 {
 804     HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass);
 805
 806     hc->unplug = qdev_simple_device_unplug_cb;
 807 }
 808
 809 static const TypeInfo xensysbus_info = {
 810     .name       = TYPE_XENSYSBUS,
 811     .parent     = TYPE_BUS,
 812     .class_init = xen_sysbus_class_init,
 813     .interfaces = (InterfaceInfo[]) {
 814         { TYPE_HOTPLUG_HANDLER },
 815         { }
 816     }
 817 };
 818
 819 static Property xen_sysdev_properties[] = {
 820     {/* end of property list */},
 821 };
 822
 823 static void xen_sysdev_class_init(ObjectClass *klass, void *data)
 824 {
 825     DeviceClass *dc = DEVICE_CLASS(klass);
 826
 827     dc->props = xen_sysdev_properties;
 828     dc->bus_type = TYPE_XENSYSBUS;
 829 }
 830
 831 static const TypeInfo xensysdev_info = {
 832     .name          = TYPE_XENSYSDEV,
 833     .parent        = TYPE_SYS_BUS_DEVICE,
 834     .instance_size = sizeof(SysBusDevice),
 835     .class_init    = xen_sysdev_class_init,
 836 };
 837
 838 static void xenbe_register_types(void)
 839 {
 840     type_register_static(&xensysbus_info);
 841     type_register_static(&xensysdev_info);
 842     type_register_static(&xendev_type_info);
 843 }
 844
 845 type_init(xenbe_register_types)