src/automount.c

   1 /*-*- Mode: C; c-basic-offset: 8 -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2010 Lennart Poettering
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU General Public License as published by
  10   the Free Software Foundation; either version 2 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   General Public License for more details.
  17
  18   You should have received a copy of the GNU General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <errno.h>
  23 #include <limits.h>
  24 #include <sys/mount.h>
  25 #include <unistd.h>
  26 #include <fcntl.h>
  27 #include <sys/epoll.h>
  28 #include <sys/stat.h>
  29 #include <linux/auto_fs4.h>
  30 #include <linux/auto_dev-ioctl.h>
  31
  32 #include "unit.h"
  33 #include "automount.h"
  34 #include "load-fragment.h"
  35 #include "load-dropin.h"
  36 #include "unit-name.h"
  37 #include "dbus-automount.h"
  38 #include "bus-errors.h"
  39 #include "special.h"
  40
  41 static const UnitActiveState state_translation_table[_AUTOMOUNT_STATE_MAX] = {
  42         [AUTOMOUNT_DEAD] = UNIT_INACTIVE,
  43         [AUTOMOUNT_WAITING] = UNIT_ACTIVE,
  44         [AUTOMOUNT_RUNNING] = UNIT_ACTIVE,
  45         [AUTOMOUNT_MAINTENANCE] = UNIT_MAINTENANCE
  46 };
  47
  48 static int open_dev_autofs(Manager *m);
  49
  50 static void automount_init(Unit *u) {
  51         Automount *a = AUTOMOUNT(u);
  52
  53         assert(u);
  54         assert(u->meta.load_state == UNIT_STUB);
  55
  56         a->pipe_watch.fd = a->pipe_fd = -1;
  57         a->pipe_watch.type = WATCH_INVALID;
  58
  59         a->directory_mode = 0755;
  60 }
  61
  62 static void repeat_unmout(const char *path) {
  63         assert(path);
  64
  65         for (;;) {
  66                 /* If there are multiple mounts on a mount point, this
  67                  * removes them all */
  68
  69                 if (umount2(path, MNT_DETACH) >= 0)
  70                         continue;
  71
  72                 if (errno != EINVAL)
  73                         log_error("Failed to unmount: %m");
  74
  75                 break;
  76         }
  77 }
  78
  79 static void unmount_autofs(Automount *a) {
  80         assert(a);
  81
  82         if (a->pipe_fd < 0)
  83                 return;
  84
  85         automount_send_ready(a, -EHOSTDOWN);
  86
  87         unit_unwatch_fd(UNIT(a), &a->pipe_watch);
  88         close_nointr_nofail(a->pipe_fd);
  89         a->pipe_fd = -1;
  90
  91         /* If we reload/reexecute things we keep the mount point
  92          * around */
  93         if (a->where &&
  94             (a->meta.manager->exit_code != MANAGER_RELOAD &&
  95              a->meta.manager->exit_code != MANAGER_REEXECUTE))
  96                 repeat_unmout(a->where);
  97 }
  98
  99 static void automount_done(Unit *u) {
 100         Automount *a = AUTOMOUNT(u);
 101
 102         assert(a);
 103
 104         unmount_autofs(a);
 105         a->mount = NULL;
 106
 107         free(a->where);
 108         a->where = NULL;
 109
 110         set_free(a->tokens);
 111         a->tokens = NULL;
 112 }
 113
 114 int automount_add_one_mount_link(Automount *a, Mount *m) {
 115         int r;
 116
 117         assert(a);
 118         assert(m);
 119
 120         if (a->meta.load_state != UNIT_LOADED ||
 121             m->meta.load_state != UNIT_LOADED)
 122                 return 0;
 123
 124         if (!path_startswith(a->where, m->where))
 125                 return 0;
 126
 127         if (path_equal(a->where, m->where))
 128                 return 0;
 129
 130         if ((r = unit_add_two_dependencies(UNIT(a), UNIT_AFTER, UNIT_REQUIRES, UNIT(m), true)) < 0)
 131                 return r;
 132
 133         return 0;
 134 }
 135
 136 static int automount_add_mount_links(Automount *a) {
 137         Meta *other;
 138         int r;
 139
 140         assert(a);
 141
 142         LIST_FOREACH(units_per_type, other, a->meta.manager->units_per_type[UNIT_MOUNT])
 143                 if ((r = automount_add_one_mount_link(a, (Mount*) other)) < 0)
 144                         return r;
 145
 146         return 0;
 147 }
 148
 149 static int automount_add_default_dependencies(Automount *a) {
 150         int r;
 151
 152         assert(a);
 153
 154         if (a->meta.manager->running_as == MANAGER_SYSTEM) {
 155
 156                 if ((r = unit_add_dependency_by_name(UNIT(a), UNIT_AFTER, SPECIAL_FSCK_TARGET, NULL, true)) < 0)
 157                         return r;
 158
 159                 if ((r = unit_add_two_dependencies_by_name(UNIT(a), UNIT_BEFORE, UNIT_CONFLICTED_BY, SPECIAL_UMOUNT_TARGET, NULL, true)) < 0)
 160                         return r;
 161         }
 162
 163         return 0;
 164 }
 165
 166 static int automount_verify(Automount *a) {
 167         bool b;
 168         char *e;
 169         assert(a);
 170
 171         if (a->meta.load_state != UNIT_LOADED)
 172                 return 0;
 173
 174         if (path_equal(a->where, "/")) {
 175                 log_error("Cannot have an automount unit for the root directory. Refusing.");
 176                 return -EINVAL;
 177         }
 178
 179         if (!(e = unit_name_from_path(a->where, ".automount")))
 180                 return -ENOMEM;
 181
 182         b = unit_has_name(UNIT(a), e);
 183         free(e);
 184
 185         if (!b) {
 186                 log_error("%s's Where setting doesn't match unit name. Refusing.", a->meta.id);
 187                 return -EINVAL;
 188         }
 189
 190         return 0;
 191 }
 192
 193 static int automount_load(Unit *u) {
 194         int r;
 195         Automount *a = AUTOMOUNT(u);
 196
 197         assert(u);
 198         assert(u->meta.load_state == UNIT_STUB);
 199
 200         /* Load a .automount file */
 201         if ((r = unit_load_fragment_and_dropin_optional(u)) < 0)
 202                 return r;
 203
 204         if (u->meta.load_state == UNIT_LOADED) {
 205
 206                 if (!a->where)
 207                         if (!(a->where = unit_name_to_path(u->meta.id)))
 208                                 return -ENOMEM;
 209
 210                 path_kill_slashes(a->where);
 211
 212                 if ((r = automount_add_mount_links(a)) < 0)
 213                         return r;
 214
 215                 if ((r = unit_load_related_unit(u, ".mount", (Unit**) &a->mount)) < 0)
 216                         return r;
 217
 218                 if ((r = unit_add_dependency(u, UNIT_BEFORE, UNIT(a->mount), true)) < 0)
 219                         return r;
 220
 221                 if (a->meta.default_dependencies)
 222                         if ((r = automount_add_default_dependencies(a)) < 0)
 223                                 return r;
 224         }
 225
 226         return automount_verify(a);
 227 }
 228
 229 static void automount_set_state(Automount *a, AutomountState state) {
 230         AutomountState old_state;
 231         assert(a);
 232
 233         old_state = a->state;
 234         a->state = state;
 235
 236         if (state != AUTOMOUNT_WAITING &&
 237             state != AUTOMOUNT_RUNNING)
 238                 unmount_autofs(a);
 239
 240         if (state != old_state)
 241                 log_debug("%s changed %s -> %s",
 242                           a->meta.id,
 243                           automount_state_to_string(old_state),
 244                           automount_state_to_string(state));
 245
 246         unit_notify(UNIT(a), state_translation_table[old_state], state_translation_table[state]);
 247 }
 248
 249 static int automount_coldplug(Unit *u) {
 250         Automount *a = AUTOMOUNT(u);
 251         int r;
 252
 253         assert(a);
 254         assert(a->state == AUTOMOUNT_DEAD);
 255
 256         if (a->deserialized_state != a->state) {
 257
 258                 if ((r = open_dev_autofs(u->meta.manager)) < 0)
 259                         return r;
 260
 261                 if (a->deserialized_state == AUTOMOUNT_WAITING ||
 262                     a->deserialized_state == AUTOMOUNT_RUNNING) {
 263
 264                         assert(a->pipe_fd >= 0);
 265
 266                         if ((r = unit_watch_fd(UNIT(a), a->pipe_fd, EPOLLIN, &a->pipe_watch)) < 0)
 267                                 return r;
 268                 }
 269
 270                 automount_set_state(a, a->deserialized_state);
 271         }
 272
 273         return 0;
 274 }
 275
 276 static void automount_dump(Unit *u, FILE *f, const char *prefix) {
 277         Automount *a = AUTOMOUNT(u);
 278
 279         assert(a);
 280
 281         fprintf(f,
 282                 "%sAutomount State: %s\n"
 283                 "%sWhere: %s\n"
 284                 "%sDirectoryMode: %04o\n",
 285                 prefix, automount_state_to_string(a->state),
 286                 prefix, a->where,
 287                 prefix, a->directory_mode);
 288 }
 289
 290 static void automount_enter_dead(Automount *a, bool success) {
 291         assert(a);
 292
 293         if (!success)
 294                 a->failure = true;
 295
 296         automount_set_state(a, a->failure ? AUTOMOUNT_MAINTENANCE : AUTOMOUNT_DEAD);
 297 }
 298
 299 static int open_dev_autofs(Manager *m) {
 300         struct autofs_dev_ioctl param;
 301
 302         assert(m);
 303
 304         if (m->dev_autofs_fd >= 0)
 305                 return m->dev_autofs_fd;
 306
 307         label_fix("/dev/autofs");
 308
 309         if ((m->dev_autofs_fd = open("/dev/autofs", O_CLOEXEC|O_RDONLY)) < 0) {
 310                 log_error("Failed to open /dev/autofs: %s", strerror(errno));
 311                 return -errno;
 312         }
 313
 314         init_autofs_dev_ioctl(&param);
 315         if (ioctl(m->dev_autofs_fd, AUTOFS_DEV_IOCTL_VERSION, &param) < 0) {
 316                 close_nointr_nofail(m->dev_autofs_fd);
 317                 m->dev_autofs_fd = -1;
 318                 return -errno;
 319         }
 320
 321         log_debug("Autofs kernel version %i.%i", param.ver_major, param.ver_minor);
 322
 323         return m->dev_autofs_fd;
 324 }
 325
 326 static int open_ioctl_fd(int dev_autofs_fd, const char *where, dev_t devid) {
 327         struct autofs_dev_ioctl *param;
 328         size_t l;
 329         int r;
 330
 331         assert(dev_autofs_fd >= 0);
 332         assert(where);
 333
 334         l = sizeof(struct autofs_dev_ioctl) + strlen(where) + 1;
 335
 336         if (!(param = malloc(l)))
 337                 return -ENOMEM;
 338
 339         init_autofs_dev_ioctl(param);
 340         param->size = l;
 341         param->ioctlfd = -1;
 342         param->openmount.devid = devid;
 343         strcpy(param->path, where);
 344
 345         if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_OPENMOUNT, param) < 0) {
 346                 r = -errno;
 347                 goto finish;
 348         }
 349
 350         if (param->ioctlfd < 0) {
 351                 r = -EIO;
 352                 goto finish;
 353         }
 354
 355         fd_cloexec(param->ioctlfd, true);
 356         r = param->ioctlfd;
 357
 358 finish:
 359         free(param);
 360         return r;
 361 }
 362
 363 static int autofs_protocol(int dev_autofs_fd, int ioctl_fd) {
 364         uint32_t major, minor;
 365         struct autofs_dev_ioctl param;
 366
 367         assert(dev_autofs_fd >= 0);
 368         assert(ioctl_fd >= 0);
 369
 370         init_autofs_dev_ioctl(&param);
 371         param.ioctlfd = ioctl_fd;
 372
 373         if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_PROTOVER, &param) < 0)
 374                 return -errno;
 375
 376         major = param.protover.version;
 377
 378         init_autofs_dev_ioctl(&param);
 379         param.ioctlfd = ioctl_fd;
 380
 381         if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_PROTOSUBVER, &param) < 0)
 382                 return -errno;
 383
 384         minor = param.protosubver.sub_version;
 385
 386         log_debug("Autofs protocol version %i.%i", major, minor);
 387         return 0;
 388 }
 389
 390 static int autofs_set_timeout(int dev_autofs_fd, int ioctl_fd, time_t sec) {
 391         struct autofs_dev_ioctl param;
 392
 393         assert(dev_autofs_fd >= 0);
 394         assert(ioctl_fd >= 0);
 395
 396         init_autofs_dev_ioctl(&param);
 397         param.ioctlfd = ioctl_fd;
 398         param.timeout.timeout = sec;
 399
 400         if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_TIMEOUT, &param) < 0)
 401                 return -errno;
 402
 403         return 0;
 404 }
 405
 406 static int autofs_send_ready(int dev_autofs_fd, int ioctl_fd, uint32_t token, int status) {
 407         struct autofs_dev_ioctl param;
 408
 409         assert(dev_autofs_fd >= 0);
 410         assert(ioctl_fd >= 0);
 411
 412         init_autofs_dev_ioctl(&param);
 413         param.ioctlfd = ioctl_fd;
 414
 415         if (status) {
 416                 param.fail.token = token;
 417                 param.fail.status = status;
 418         } else
 419                 param.ready.token = token;
 420
 421         if (ioctl(dev_autofs_fd, status ? AUTOFS_DEV_IOCTL_FAIL : AUTOFS_DEV_IOCTL_READY, &param) < 0)
 422                 return -errno;
 423
 424         return 0;
 425 }
 426
 427 int automount_send_ready(Automount *a, int status) {
 428         int ioctl_fd, r;
 429         unsigned token;
 430
 431         assert(a);
 432         assert(status <= 0);
 433
 434         if (set_isempty(a->tokens))
 435                 return 0;
 436
 437         if ((ioctl_fd = open_ioctl_fd(a->meta.manager->dev_autofs_fd, a->where, a->dev_id)) < 0) {
 438                 r = ioctl_fd;
 439                 goto fail;
 440         }
 441
 442         if (status)
 443                 log_debug("Sending failure: %s", strerror(-status));
 444         else
 445                 log_debug("Sending success.");
 446
 447         r = 0;
 448
 449         /* Autofs thankfully does not hand out 0 as a token */
 450         while ((token = PTR_TO_UINT(set_steal_first(a->tokens)))) {
 451                 int k;
 452
 453                 /* Autofs fun fact II:
 454                  *
 455                  * if you pass a positive status code here, the kernel will
 456                  * freeze! Yay! */
 457
 458                 if ((k = autofs_send_ready(a->meta.manager->dev_autofs_fd,
 459                                            ioctl_fd,
 460                                            token,
 461                                            status)) < 0)
 462                         r = k;
 463         }
 464
 465 fail:
 466         if (ioctl_fd >= 0)
 467                 close_nointr_nofail(ioctl_fd);
 468
 469         return r;
 470 }
 471
 472 static void automount_enter_waiting(Automount *a) {
 473         int p[2] = { -1, -1 };
 474         char name[32], options[128];
 475         bool mounted = false;
 476         int r, ioctl_fd = -1, dev_autofs_fd;
 477         struct stat st;
 478
 479         assert(a);
 480         assert(a->pipe_fd < 0);
 481         assert(a->where);
 482
 483         if (a->tokens)
 484                 set_clear(a->tokens);
 485
 486         if ((dev_autofs_fd = open_dev_autofs(a->meta.manager)) < 0) {
 487                 r = dev_autofs_fd;
 488                 goto fail;
 489         }
 490
 491         /* We knowingly ignore the results of this call */
 492         mkdir_p(a->where, 0555);
 493
 494         if (pipe2(p, O_NONBLOCK|O_CLOEXEC) < 0) {
 495                 r = -errno;
 496                 goto fail;
 497         }
 498
 499         snprintf(options, sizeof(options), "fd=%i,pgrp=%u,minproto=5,maxproto=5,direct", p[1], (unsigned) getpgrp());
 500         char_array_0(options);
 501
 502         snprintf(name, sizeof(name), "systemd-%u", (unsigned) getpid());
 503         char_array_0(name);
 504
 505         if (mount(name, a->where, "autofs", 0, options) < 0) {
 506                 r = -errno;
 507                 goto fail;
 508         }
 509
 510         mounted = true;
 511
 512         close_nointr_nofail(p[1]);
 513         p[1] = -1;
 514
 515         if (stat(a->where, &st) < 0) {
 516                 r = -errno;
 517                 goto fail;
 518         }
 519
 520         if ((ioctl_fd = open_ioctl_fd(dev_autofs_fd, a->where, st.st_dev)) < 0) {
 521                 r = ioctl_fd;
 522                 goto fail;
 523         }
 524
 525         if ((r = autofs_protocol(dev_autofs_fd, ioctl_fd)) < 0)
 526                 goto fail;
 527
 528         if ((r = autofs_set_timeout(dev_autofs_fd, ioctl_fd, 300)) < 0)
 529                 goto fail;
 530
 531         /* Autofs fun fact:
 532          *
 533          * Unless we close the ioctl fd here, for some weird reason
 534          * the direct mount will not receive events from the
 535          * kernel. */
 536
 537         close_nointr_nofail(ioctl_fd);
 538         ioctl_fd = -1;
 539
 540         if ((r = unit_watch_fd(UNIT(a), p[0], EPOLLIN, &a->pipe_watch)) < 0)
 541                 goto fail;
 542
 543         a->pipe_fd = p[0];
 544         a->dev_id = st.st_dev;
 545
 546         automount_set_state(a, AUTOMOUNT_WAITING);
 547
 548         return;
 549
 550 fail:
 551         assert_se(close_pipe(p) == 0);
 552
 553         if (ioctl_fd >= 0)
 554                 close_nointr_nofail(ioctl_fd);
 555
 556         if (mounted)
 557                 repeat_unmout(a->where);
 558
 559         log_error("Failed to initialize automounter: %s", strerror(-r));
 560         automount_enter_dead(a, false);
 561 }
 562
 563 static void automount_enter_runnning(Automount *a) {
 564         int r;
 565         struct stat st;
 566         DBusError error;
 567
 568         assert(a);
 569         assert(a->mount);
 570
 571         dbus_error_init(&error);
 572
 573         /* We don't take mount requests anymore if we are supposed to
 574          * shut down anyway */
 575         if (a->meta.job && a->meta.job->type == JOB_STOP) {
 576                 automount_send_ready(a, -EHOSTDOWN);
 577                 return;
 578         }
 579
 580         mkdir_p(a->where, a->directory_mode);
 581
 582         /* Before we do anything, let's see if somebody is playing games with us? */
 583         if (lstat(a->where, &st) < 0) {
 584                 log_warning("%s failed stat automount point: %m", a->meta.id);
 585                 goto fail;
 586         }
 587
 588         if (!S_ISDIR(st.st_mode) || st.st_dev != a->dev_id)
 589                 log_info("%s's automount point already active?", a->meta.id);
 590         else if ((r = manager_add_job(a->meta.manager, JOB_START, UNIT(a->mount), JOB_REPLACE, true, &error, NULL)) < 0) {
 591                 log_warning("%s failed to queue mount startup job: %s", a->meta.id, bus_error(&error, r));
 592                 goto fail;
 593         }
 594
 595         automount_set_state(a, AUTOMOUNT_RUNNING);
 596         return;
 597
 598 fail:
 599         automount_enter_dead(a, false);
 600         dbus_error_free(&error);
 601 }
 602
 603 static int automount_start(Unit *u) {
 604         Automount *a = AUTOMOUNT(u);
 605
 606         assert(a);
 607
 608         assert(a->state == AUTOMOUNT_DEAD || a->state == AUTOMOUNT_MAINTENANCE);
 609
 610         if (path_is_mount_point(a->where)) {
 611                 log_error("Path %s is already a mount point, refusing start for %s", a->where, u->meta.id);
 612                 return -EEXIST;
 613         }
 614
 615         if (a->mount->meta.load_state != UNIT_LOADED)
 616                 return -ENOENT;
 617
 618         a->failure = false;
 619         automount_enter_waiting(a);
 620         return 0;
 621 }
 622
 623 static int automount_stop(Unit *u) {
 624         Automount *a = AUTOMOUNT(u);
 625
 626         assert(a);
 627
 628         assert(a->state == AUTOMOUNT_WAITING || a->state == AUTOMOUNT_RUNNING);
 629
 630         automount_enter_dead(a, true);
 631         return 0;
 632 }
 633
 634 static int automount_serialize(Unit *u, FILE *f, FDSet *fds) {
 635         Automount *a = AUTOMOUNT(u);
 636         void *p;
 637         Iterator i;
 638
 639         assert(a);
 640         assert(f);
 641         assert(fds);
 642
 643         unit_serialize_item(u, f, "state", automount_state_to_string(a->state));
 644         unit_serialize_item(u, f, "failure", yes_no(a->failure));
 645         unit_serialize_item_format(u, f, "dev-id", "%u", (unsigned) a->dev_id);
 646
 647         SET_FOREACH(p, a->tokens, i)
 648                 unit_serialize_item_format(u, f, "token", "%u", PTR_TO_UINT(p));
 649
 650         if (a->pipe_fd >= 0) {
 651                 int copy;
 652
 653                 if ((copy = fdset_put_dup(fds, a->pipe_fd)) < 0)
 654                         return copy;
 655
 656                 unit_serialize_item_format(u, f, "pipe-fd", "%i", copy);
 657         }
 658
 659         return 0;
 660 }
 661
 662 static int automount_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) {
 663         Automount *a = AUTOMOUNT(u);
 664         int r;
 665
 666         assert(a);
 667         assert(fds);
 668
 669         if (streq(key, "state")) {
 670                 AutomountState state;
 671
 672                 if ((state = automount_state_from_string(value)) < 0)
 673                         log_debug("Failed to parse state value %s", value);
 674                 else
 675                         a->deserialized_state = state;
 676         } else if (streq(key, "failure")) {
 677                 int b;
 678
 679                 if ((b = parse_boolean(value)) < 0)
 680                         log_debug("Failed to parse failure value %s", value);
 681                 else
 682                         a->failure = b || a->failure;
 683         } else if (streq(key, "dev-id")) {
 684                 unsigned d;
 685
 686                 if (safe_atou(value, &d) < 0)
 687                         log_debug("Failed to parse dev-id value %s", value);
 688                 else
 689                         a->dev_id = (unsigned) d;
 690         } else if (streq(key, "token")) {
 691                 unsigned token;
 692
 693                 if (safe_atou(value, &token) < 0)
 694                         log_debug("Failed to parse token value %s", value);
 695                 else {
 696                         if (!a->tokens)
 697                                 if (!(a->tokens = set_new(trivial_hash_func, trivial_compare_func)))
 698                                         return -ENOMEM;
 699
 700                         if ((r = set_put(a->tokens, UINT_TO_PTR(token))) < 0)
 701                                 return r;
 702                 }
 703         } else if (streq(key, "pipe-fd")) {
 704                 int fd;
 705
 706                 if (safe_atoi(value, &fd) < 0 || fd < 0 || !fdset_contains(fds, fd))
 707                         log_debug("Failed to parse pipe-fd value %s", value);
 708                 else {
 709                         if (a->pipe_fd >= 0)
 710                                 close_nointr_nofail(a->pipe_fd);
 711
 712                         a->pipe_fd = fdset_remove(fds, fd);
 713                 }
 714         } else
 715                 log_debug("Unknown serialization key '%s'", key);
 716
 717         return 0;
 718 }
 719
 720 static UnitActiveState automount_active_state(Unit *u) {
 721         assert(u);
 722
 723         return state_translation_table[AUTOMOUNT(u)->state];
 724 }
 725
 726 static const char *automount_sub_state_to_string(Unit *u) {
 727         assert(u);
 728
 729         return automount_state_to_string(AUTOMOUNT(u)->state);
 730 }
 731
 732 static bool automount_check_gc(Unit *u) {
 733         Automount *a = AUTOMOUNT(u);
 734
 735         assert(a);
 736
 737         return UNIT_VTABLE(UNIT(a->mount))->check_gc(UNIT(a->mount));
 738 }
 739
 740 static void automount_fd_event(Unit *u, int fd, uint32_t events, Watch *w) {
 741         Automount *a = AUTOMOUNT(u);
 742         union autofs_v5_packet_union packet;
 743         ssize_t l;
 744         int r;
 745
 746         assert(a);
 747         assert(fd == a->pipe_fd);
 748
 749         if (events != EPOLLIN) {
 750                 log_error("Got invalid poll event on pipe.");
 751                 goto fail;
 752         }
 753
 754         if ((l = loop_read(a->pipe_fd, &packet, sizeof(packet), true)) != sizeof(packet)) {
 755                 log_error("Invalid read from pipe: %s", l < 0 ? strerror(-l) : "short read");
 756                 goto fail;
 757         }
 758
 759         switch (packet.hdr.type) {
 760
 761         case autofs_ptype_missing_direct:
 762                 log_debug("Got direct mount request for %s", packet.v5_packet.name);
 763
 764                 if (!a->tokens)
 765                         if (!(a->tokens = set_new(trivial_hash_func, trivial_compare_func))) {
 766                                 log_error("Failed to allocate token set.");
 767                                 goto fail;
 768                         }
 769
 770                 if ((r = set_put(a->tokens, UINT_TO_PTR(packet.v5_packet.wait_queue_token))) < 0) {
 771                         log_error("Failed to remember token: %s", strerror(-r));
 772                         goto fail;
 773                 }
 774
 775                 automount_enter_runnning(a);
 776                 break;
 777
 778         default:
 779                 log_error("Received unknown automount request %i", packet.hdr.type);
 780                 break;
 781         }
 782
 783         return;
 784
 785 fail:
 786         automount_enter_dead(a, false);
 787 }
 788
 789 static void automount_shutdown(Manager *m) {
 790         assert(m);
 791
 792         if (m->dev_autofs_fd >= 0)
 793                 close_nointr_nofail(m->dev_autofs_fd);
 794 }
 795
 796 static void automount_reset_maintenance(Unit *u) {
 797         Automount *a = AUTOMOUNT(u);
 798
 799         assert(a);
 800
 801         if (a->state == AUTOMOUNT_MAINTENANCE)
 802                 automount_set_state(a, AUTOMOUNT_DEAD);
 803
 804         a->failure = false;
 805 }
 806
 807 static const char* const automount_state_table[_AUTOMOUNT_STATE_MAX] = {
 808         [AUTOMOUNT_DEAD] = "dead",
 809         [AUTOMOUNT_WAITING] = "waiting",
 810         [AUTOMOUNT_RUNNING] = "running",
 811         [AUTOMOUNT_MAINTENANCE] = "maintenance"
 812 };
 813
 814 DEFINE_STRING_TABLE_LOOKUP(automount_state, AutomountState);
 815
 816 const UnitVTable automount_vtable = {
 817         .suffix = ".automount",
 818
 819         .no_alias = true,
 820         .no_instances = true,
 821
 822         .init = automount_init,
 823         .load = automount_load,
 824         .done = automount_done,
 825
 826         .coldplug = automount_coldplug,
 827
 828         .dump = automount_dump,
 829
 830         .start = automount_start,
 831         .stop = automount_stop,
 832
 833         .serialize = automount_serialize,
 834         .deserialize_item = automount_deserialize_item,
 835
 836         .active_state = automount_active_state,
 837         .sub_state_to_string = automount_sub_state_to_string,
 838
 839         .check_gc = automount_check_gc,
 840
 841         .fd_event = automount_fd_event,
 842
 843         .reset_maintenance = automount_reset_maintenance,
 844
 845         .bus_message_handler = bus_automount_message_handler,
 846
 847         .shutdown = automount_shutdown
 848 };