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_SYSINIT_TARGET, NULL, true)) < 0)
 157                         return r;
 158
 159                 if ((r = unit_add_two_dependencies_by_name(UNIT(a), UNIT_BEFORE, UNIT_CONFLICTS, 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         if ((m->dev_autofs_fd = open("/dev/autofs", O_CLOEXEC|O_RDONLY)) < 0) {
 308                 log_error("Failed to open /dev/autofs: %s", strerror(errno));
 309                 return -errno;
 310         }
 311
 312         init_autofs_dev_ioctl(&param);
 313         if (ioctl(m->dev_autofs_fd, AUTOFS_DEV_IOCTL_VERSION, &param) < 0) {
 314                 close_nointr_nofail(m->dev_autofs_fd);
 315                 m->dev_autofs_fd = -1;
 316                 return -errno;
 317         }
 318
 319         log_debug("Autofs kernel version %i.%i", param.ver_major, param.ver_minor);
 320
 321         return m->dev_autofs_fd;
 322 }
 323
 324 static int open_ioctl_fd(int dev_autofs_fd, const char *where, dev_t devid) {
 325         struct autofs_dev_ioctl *param;
 326         size_t l;
 327         int r;
 328
 329         assert(dev_autofs_fd >= 0);
 330         assert(where);
 331
 332         l = sizeof(struct autofs_dev_ioctl) + strlen(where) + 1;
 333
 334         if (!(param = malloc(l)))
 335                 return -ENOMEM;
 336
 337         init_autofs_dev_ioctl(param);
 338         param->size = l;
 339         param->ioctlfd = -1;
 340         param->openmount.devid = devid;
 341         strcpy(param->path, where);
 342
 343         if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_OPENMOUNT, param) < 0) {
 344                 r = -errno;
 345                 goto finish;
 346         }
 347
 348         if (param->ioctlfd < 0) {
 349                 r = -EIO;
 350                 goto finish;
 351         }
 352
 353         fd_cloexec(param->ioctlfd, true);
 354         r = param->ioctlfd;
 355
 356 finish:
 357         free(param);
 358         return r;
 359 }
 360
 361 static int autofs_protocol(int dev_autofs_fd, int ioctl_fd) {
 362         uint32_t major, minor;
 363         struct autofs_dev_ioctl param;
 364
 365         assert(dev_autofs_fd >= 0);
 366         assert(ioctl_fd >= 0);
 367
 368         init_autofs_dev_ioctl(&param);
 369         param.ioctlfd = ioctl_fd;
 370
 371         if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_PROTOVER, &param) < 0)
 372                 return -errno;
 373
 374         major = param.protover.version;
 375
 376         init_autofs_dev_ioctl(&param);
 377         param.ioctlfd = ioctl_fd;
 378
 379         if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_PROTOSUBVER, &param) < 0)
 380                 return -errno;
 381
 382         minor = param.protosubver.sub_version;
 383
 384         log_debug("Autofs protocol version %i.%i", major, minor);
 385         return 0;
 386 }
 387
 388 static int autofs_set_timeout(int dev_autofs_fd, int ioctl_fd, time_t sec) {
 389         struct autofs_dev_ioctl param;
 390
 391         assert(dev_autofs_fd >= 0);
 392         assert(ioctl_fd >= 0);
 393
 394         init_autofs_dev_ioctl(&param);
 395         param.ioctlfd = ioctl_fd;
 396         param.timeout.timeout = sec;
 397
 398         if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_TIMEOUT, &param) < 0)
 399                 return -errno;
 400
 401         return 0;
 402 }
 403
 404 static int autofs_send_ready(int dev_autofs_fd, int ioctl_fd, uint32_t token, int status) {
 405         struct autofs_dev_ioctl param;
 406
 407         assert(dev_autofs_fd >= 0);
 408         assert(ioctl_fd >= 0);
 409
 410         init_autofs_dev_ioctl(&param);
 411         param.ioctlfd = ioctl_fd;
 412
 413         if (status) {
 414                 param.fail.token = token;
 415                 param.fail.status = status;
 416         } else
 417                 param.ready.token = token;
 418
 419         if (ioctl(dev_autofs_fd, status ? AUTOFS_DEV_IOCTL_FAIL : AUTOFS_DEV_IOCTL_READY, &param) < 0)
 420                 return -errno;
 421
 422         return 0;
 423 }
 424
 425 int automount_send_ready(Automount *a, int status) {
 426         int ioctl_fd, r;
 427         unsigned token;
 428
 429         assert(a);
 430         assert(status <= 0);
 431
 432         if (set_isempty(a->tokens))
 433                 return 0;
 434
 435         if ((ioctl_fd = open_ioctl_fd(a->meta.manager->dev_autofs_fd, a->where, a->dev_id)) < 0) {
 436                 r = ioctl_fd;
 437                 goto fail;
 438         }
 439
 440         if (status)
 441                 log_debug("Sending failure: %s", strerror(-status));
 442         else
 443                 log_debug("Sending success.");
 444
 445         /* Autofs thankfully does not hand out 0 as a token */
 446         while ((token = PTR_TO_UINT(set_steal_first(a->tokens)))) {
 447                 int k;
 448
 449                 /* Autofs fun fact II:
 450                  *
 451                  * if you pass a positive status code here, the kernel will
 452                  * freeze! Yay! */
 453
 454                 if ((k = autofs_send_ready(a->meta.manager->dev_autofs_fd,
 455                                            ioctl_fd,
 456                                            token,
 457                                            status)) < 0)
 458                         r = k;
 459         }
 460
 461         r = 0;
 462
 463 fail:
 464         if (ioctl_fd >= 0)
 465                 close_nointr_nofail(ioctl_fd);
 466
 467         return r;
 468 }
 469
 470 static void automount_enter_waiting(Automount *a) {
 471         int p[2] = { -1, -1 };
 472         char name[32], options[128];
 473         bool mounted = false;
 474         int r, ioctl_fd = -1, dev_autofs_fd;
 475         struct stat st;
 476
 477         assert(a);
 478         assert(a->pipe_fd < 0);
 479         assert(a->where);
 480
 481         if (a->tokens)
 482                 set_clear(a->tokens);
 483
 484         if ((dev_autofs_fd = open_dev_autofs(a->meta.manager)) < 0) {
 485                 r = dev_autofs_fd;
 486                 goto fail;
 487         }
 488
 489         /* We knowingly ignore the results of this call */
 490         mkdir_p(a->where, 0555);
 491
 492         if (pipe2(p, O_NONBLOCK|O_CLOEXEC) < 0) {
 493                 r = -errno;
 494                 goto fail;
 495         }
 496
 497         snprintf(options, sizeof(options), "fd=%i,pgrp=%u,minproto=5,maxproto=5,direct", p[1], (unsigned) getpgrp());
 498         char_array_0(options);
 499
 500         snprintf(name, sizeof(name), "systemd-%u", (unsigned) getpid());
 501         char_array_0(name);
 502
 503         if (mount(name, a->where, "autofs", 0, options) < 0) {
 504                 r = -errno;
 505                 goto fail;
 506         }
 507
 508         mounted = true;
 509
 510         close_nointr_nofail(p[1]);
 511         p[1] = -1;
 512
 513         if (stat(a->where, &st) < 0) {
 514                 r = -errno;
 515                 goto fail;
 516         }
 517
 518         if ((ioctl_fd = open_ioctl_fd(dev_autofs_fd, a->where, st.st_dev)) < 0) {
 519                 r = ioctl_fd;
 520                 goto fail;
 521         }
 522
 523         if ((r = autofs_protocol(dev_autofs_fd, ioctl_fd)) < 0)
 524                 goto fail;
 525
 526         if ((r = autofs_set_timeout(dev_autofs_fd, ioctl_fd, 300)) < 0)
 527                 goto fail;
 528
 529         /* Autofs fun fact:
 530          *
 531          * Unless we close the ioctl fd here, for some weird reason
 532          * the direct mount will not receive events from the
 533          * kernel. */
 534
 535         close_nointr_nofail(ioctl_fd);
 536         ioctl_fd = -1;
 537
 538         if ((r = unit_watch_fd(UNIT(a), p[0], EPOLLIN, &a->pipe_watch)) < 0)
 539                 goto fail;
 540
 541         a->pipe_fd = p[0];
 542         a->dev_id = st.st_dev;
 543
 544         automount_set_state(a, AUTOMOUNT_WAITING);
 545
 546         return;
 547
 548 fail:
 549         assert_se(close_pipe(p) == 0);
 550
 551         if (ioctl_fd >= 0)
 552                 close_nointr_nofail(ioctl_fd);
 553
 554         if (mounted)
 555                 repeat_unmout(a->where);
 556
 557         log_error("Failed to initialize automounter: %s", strerror(-r));
 558         automount_enter_dead(a, false);
 559 }
 560
 561 static void automount_enter_runnning(Automount *a) {
 562         int r;
 563         struct stat st;
 564         DBusError error;
 565
 566         assert(a);
 567         assert(a->mount);
 568
 569         dbus_error_init(&error);
 570
 571         /* We don't take mount requests anymore if we are supposed to
 572          * shut down anyway */
 573         if (a->meta.job && a->meta.job->type == JOB_STOP) {
 574                 automount_send_ready(a, -EHOSTDOWN);
 575                 return;
 576         }
 577
 578         mkdir_p(a->where, a->directory_mode);
 579
 580         /* Before we do anything, let's see if somebody is playing games with us? */
 581         if (lstat(a->where, &st) < 0) {
 582                 log_warning("%s failed stat automount point: %m", a->meta.id);
 583                 goto fail;
 584         }
 585
 586         if (!S_ISDIR(st.st_mode) || st.st_dev != a->dev_id)
 587                 log_info("%s's automount point already active?", a->meta.id);
 588         else if ((r = manager_add_job(a->meta.manager, JOB_START, UNIT(a->mount), JOB_REPLACE, true, &error, NULL)) < 0) {
 589                 log_warning("%s failed to queue mount startup job: %s", a->meta.id, bus_error(&error, r));
 590                 goto fail;
 591         }
 592
 593         automount_set_state(a, AUTOMOUNT_RUNNING);
 594         return;
 595
 596 fail:
 597         automount_enter_dead(a, false);
 598         dbus_error_free(&error);
 599 }
 600
 601 static int automount_start(Unit *u) {
 602         Automount *a = AUTOMOUNT(u);
 603
 604         assert(a);
 605
 606         assert(a->state == AUTOMOUNT_DEAD || a->state == AUTOMOUNT_MAINTENANCE);
 607
 608         if (path_is_mount_point(a->where)) {
 609                 log_error("Path %s is already a mount point, refusing start for %s", a->where, u->meta.id);
 610                 return -EEXIST;
 611         }
 612
 613         if (a->mount->meta.load_state != UNIT_LOADED)
 614                 return -ENOENT;
 615
 616         a->failure = false;
 617         automount_enter_waiting(a);
 618         return 0;
 619 }
 620
 621 static int automount_stop(Unit *u) {
 622         Automount *a = AUTOMOUNT(u);
 623
 624         assert(a);
 625
 626         assert(a->state == AUTOMOUNT_WAITING || a->state == AUTOMOUNT_RUNNING);
 627
 628         automount_enter_dead(a, true);
 629         return 0;
 630 }
 631
 632 static int automount_serialize(Unit *u, FILE *f, FDSet *fds) {
 633         Automount *a = AUTOMOUNT(u);
 634         void *p;
 635         Iterator i;
 636
 637         assert(a);
 638         assert(f);
 639         assert(fds);
 640
 641         unit_serialize_item(u, f, "state", automount_state_to_string(a->state));
 642         unit_serialize_item(u, f, "failure", yes_no(a->failure));
 643         unit_serialize_item_format(u, f, "dev-id", "%u", (unsigned) a->dev_id);
 644
 645         SET_FOREACH(p, a->tokens, i)
 646                 unit_serialize_item_format(u, f, "token", "%u", PTR_TO_UINT(p));
 647
 648         if (a->pipe_fd >= 0) {
 649                 int copy;
 650
 651                 if ((copy = fdset_put_dup(fds, a->pipe_fd)) < 0)
 652                         return copy;
 653
 654                 unit_serialize_item_format(u, f, "pipe-fd", "%i", copy);
 655         }
 656
 657         return 0;
 658 }
 659
 660 static int automount_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) {
 661         Automount *a = AUTOMOUNT(u);
 662         int r;
 663
 664         assert(a);
 665         assert(fds);
 666
 667         if (streq(key, "state")) {
 668                 AutomountState state;
 669
 670                 if ((state = automount_state_from_string(value)) < 0)
 671                         log_debug("Failed to parse state value %s", value);
 672                 else
 673                         a->deserialized_state = state;
 674         } else if (streq(key, "failure")) {
 675                 int b;
 676
 677                 if ((b = parse_boolean(value)) < 0)
 678                         log_debug("Failed to parse failure value %s", value);
 679                 else
 680                         a->failure = b || a->failure;
 681         } else if (streq(key, "dev-id")) {
 682                 unsigned d;
 683
 684                 if (safe_atou(value, &d) < 0)
 685                         log_debug("Failed to parse dev-id value %s", value);
 686                 else
 687                         a->dev_id = (unsigned) d;
 688         } else if (streq(key, "token")) {
 689                 unsigned token;
 690
 691                 if (safe_atou(value, &token) < 0)
 692                         log_debug("Failed to parse token value %s", value);
 693                 else {
 694                         if (!a->tokens)
 695                                 if (!(a->tokens = set_new(trivial_hash_func, trivial_compare_func)))
 696                                         return -ENOMEM;
 697
 698                         if ((r = set_put(a->tokens, UINT_TO_PTR(token))) < 0)
 699                                 return r;
 700                 }
 701         } else if (streq(key, "pipe-fd")) {
 702                 int fd;
 703
 704                 if (safe_atoi(value, &fd) < 0 || fd < 0 || !fdset_contains(fds, fd))
 705                         log_debug("Failed to parse pipe-fd value %s", value);
 706                 else {
 707                         if (a->pipe_fd >= 0)
 708                                 close_nointr_nofail(a->pipe_fd);
 709
 710                         a->pipe_fd = fdset_remove(fds, fd);
 711                 }
 712         } else
 713                 log_debug("Unknown serialization key '%s'", key);
 714
 715         return 0;
 716 }
 717
 718 static UnitActiveState automount_active_state(Unit *u) {
 719         assert(u);
 720
 721         return state_translation_table[AUTOMOUNT(u)->state];
 722 }
 723
 724 static const char *automount_sub_state_to_string(Unit *u) {
 725         assert(u);
 726
 727         return automount_state_to_string(AUTOMOUNT(u)->state);
 728 }
 729
 730 static bool automount_check_gc(Unit *u) {
 731         Automount *a = AUTOMOUNT(u);
 732
 733         assert(a);
 734
 735         return UNIT_VTABLE(UNIT(a->mount))->check_gc(UNIT(a->mount));
 736 }
 737
 738 static void automount_fd_event(Unit *u, int fd, uint32_t events, Watch *w) {
 739         Automount *a = AUTOMOUNT(u);
 740         union autofs_v5_packet_union packet;
 741         ssize_t l;
 742         int r;
 743
 744         assert(a);
 745         assert(fd == a->pipe_fd);
 746
 747         if (events != EPOLLIN) {
 748                 log_error("Got invalid poll event on pipe.");
 749                 goto fail;
 750         }
 751
 752         if ((l = loop_read(a->pipe_fd, &packet, sizeof(packet), true)) != sizeof(packet)) {
 753                 log_error("Invalid read from pipe: %s", l < 0 ? strerror(-l) : "short read");
 754                 goto fail;
 755         }
 756
 757         switch (packet.hdr.type) {
 758
 759         case autofs_ptype_missing_direct:
 760                 log_debug("Got direct mount request for %s", packet.v5_packet.name);
 761
 762                 if (!a->tokens)
 763                         if (!(a->tokens = set_new(trivial_hash_func, trivial_compare_func))) {
 764                                 log_error("Failed to allocate token set.");
 765                                 goto fail;
 766                         }
 767
 768                 if ((r = set_put(a->tokens, UINT_TO_PTR(packet.v5_packet.wait_queue_token))) < 0) {
 769                         log_error("Failed to remember token: %s", strerror(-r));
 770                         goto fail;
 771                 }
 772
 773                 automount_enter_runnning(a);
 774                 break;
 775
 776         default:
 777                 log_error("Received unknown automount request %i", packet.hdr.type);
 778                 break;
 779         }
 780
 781         return;
 782
 783 fail:
 784         automount_enter_dead(a, false);
 785 }
 786
 787 static void automount_shutdown(Manager *m) {
 788         assert(m);
 789
 790         if (m->dev_autofs_fd >= 0)
 791                 close_nointr_nofail(m->dev_autofs_fd);
 792 }
 793
 794 static void automount_reset_maintenance(Unit *u) {
 795         Automount *a = AUTOMOUNT(u);
 796
 797         assert(a);
 798
 799         if (a->state == AUTOMOUNT_MAINTENANCE)
 800                 automount_set_state(a, AUTOMOUNT_DEAD);
 801
 802         a->failure = false;
 803 }
 804
 805 static const char* const automount_state_table[_AUTOMOUNT_STATE_MAX] = {
 806         [AUTOMOUNT_DEAD] = "dead",
 807         [AUTOMOUNT_WAITING] = "waiting",
 808         [AUTOMOUNT_RUNNING] = "running",
 809         [AUTOMOUNT_MAINTENANCE] = "maintenance"
 810 };
 811
 812 DEFINE_STRING_TABLE_LOOKUP(automount_state, AutomountState);
 813
 814 const UnitVTable automount_vtable = {
 815         .suffix = ".automount",
 816
 817         .no_alias = true,
 818         .no_instances = true,
 819
 820         .init = automount_init,
 821         .load = automount_load,
 822         .done = automount_done,
 823
 824         .coldplug = automount_coldplug,
 825
 826         .dump = automount_dump,
 827
 828         .start = automount_start,
 829         .stop = automount_stop,
 830
 831         .serialize = automount_serialize,
 832         .deserialize_item = automount_deserialize_item,
 833
 834         .active_state = automount_active_state,
 835         .sub_state_to_string = automount_sub_state_to_string,
 836
 837         .check_gc = automount_check_gc,
 838
 839         .fd_event = automount_fd_event,
 840
 841         .reset_maintenance = automount_reset_maintenance,
 842
 843         .bus_message_handler = bus_automount_message_handler,
 844
 845         .shutdown = automount_shutdown
 846 };