src/automount.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   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 #include "label.h"
  41
  42 static const UnitActiveState state_translation_table[_AUTOMOUNT_STATE_MAX] = {
  43         [AUTOMOUNT_DEAD] = UNIT_INACTIVE,
  44         [AUTOMOUNT_WAITING] = UNIT_ACTIVE,
  45         [AUTOMOUNT_RUNNING] = UNIT_ACTIVE,
  46         [AUTOMOUNT_FAILED] = UNIT_FAILED
  47 };
  48
  49 static int open_dev_autofs(Manager *m);
  50
  51 static void automount_init(Unit *u) {
  52         Automount *a = AUTOMOUNT(u);
  53
  54         assert(u);
  55         assert(u->meta.load_state == UNIT_STUB);
  56
  57         a->pipe_watch.fd = a->pipe_fd = -1;
  58         a->pipe_watch.type = WATCH_INVALID;
  59
  60         a->directory_mode = 0755;
  61
  62         a->meta.ignore_on_isolate = true;
  63 }
  64
  65 static void repeat_unmout(const char *path) {
  66         assert(path);
  67
  68         for (;;) {
  69                 /* If there are multiple mounts on a mount point, this
  70                  * removes them all */
  71
  72                 if (umount2(path, MNT_DETACH) >= 0)
  73                         continue;
  74
  75                 if (errno != EINVAL)
  76                         log_error("Failed to unmount: %m");
  77
  78                 break;
  79         }
  80 }
  81
  82 static void unmount_autofs(Automount *a) {
  83         assert(a);
  84
  85         if (a->pipe_fd < 0)
  86                 return;
  87
  88         automount_send_ready(a, -EHOSTDOWN);
  89
  90         unit_unwatch_fd(UNIT(a), &a->pipe_watch);
  91         close_nointr_nofail(a->pipe_fd);
  92         a->pipe_fd = -1;
  93
  94         /* If we reload/reexecute things we keep the mount point
  95          * around */
  96         if (a->where &&
  97             (a->meta.manager->exit_code != MANAGER_RELOAD &&
  98              a->meta.manager->exit_code != MANAGER_REEXECUTE))
  99                 repeat_unmout(a->where);
 100 }
 101
 102 static void automount_done(Unit *u) {
 103         Automount *a = AUTOMOUNT(u);
 104
 105         assert(a);
 106
 107         unmount_autofs(a);
 108         unit_ref_unset(&a->mount);
 109
 110         free(a->where);
 111         a->where = NULL;
 112
 113         set_free(a->tokens);
 114         a->tokens = NULL;
 115 }
 116
 117 int automount_add_one_mount_link(Automount *a, Mount *m) {
 118         int r;
 119
 120         assert(a);
 121         assert(m);
 122
 123         if (a->meta.load_state != UNIT_LOADED ||
 124             m->meta.load_state != UNIT_LOADED)
 125                 return 0;
 126
 127         if (!path_startswith(a->where, m->where))
 128                 return 0;
 129
 130         if (path_equal(a->where, m->where))
 131                 return 0;
 132
 133         if ((r = unit_add_two_dependencies(UNIT(a), UNIT_AFTER, UNIT_REQUIRES, UNIT(m), true)) < 0)
 134                 return r;
 135
 136         return 0;
 137 }
 138
 139 static int automount_add_mount_links(Automount *a) {
 140         Meta *other;
 141         int r;
 142
 143         assert(a);
 144
 145         LIST_FOREACH(units_by_type, other, a->meta.manager->units_by_type[UNIT_MOUNT])
 146                 if ((r = automount_add_one_mount_link(a, (Mount*) other)) < 0)
 147                         return r;
 148
 149         return 0;
 150 }
 151
 152 static int automount_add_default_dependencies(Automount *a) {
 153         int r;
 154
 155         assert(a);
 156
 157         if (a->meta.manager->running_as == MANAGER_SYSTEM) {
 158
 159                 if ((r = unit_add_dependency_by_name(UNIT(a), UNIT_BEFORE, SPECIAL_BASIC_TARGET, NULL, true)) < 0)
 160                         return r;
 161
 162                 if ((r = unit_add_two_dependencies_by_name(UNIT(a), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_UMOUNT_TARGET, NULL, true)) < 0)
 163                         return r;
 164         }
 165
 166         return 0;
 167 }
 168
 169 static int automount_verify(Automount *a) {
 170         bool b;
 171         char *e;
 172         assert(a);
 173
 174         if (a->meta.load_state != UNIT_LOADED)
 175                 return 0;
 176
 177         if (path_equal(a->where, "/")) {
 178                 log_error("Cannot have an automount unit for the root directory. Refusing.");
 179                 return -EINVAL;
 180         }
 181
 182         if (!(e = unit_name_from_path(a->where, ".automount")))
 183                 return -ENOMEM;
 184
 185         b = unit_has_name(UNIT(a), e);
 186         free(e);
 187
 188         if (!b) {
 189                 log_error("%s's Where setting doesn't match unit name. Refusing.", a->meta.id);
 190                 return -EINVAL;
 191         }
 192
 193         return 0;
 194 }
 195
 196 static int automount_load(Unit *u) {
 197         int r;
 198         Automount *a = AUTOMOUNT(u);
 199
 200         assert(u);
 201         assert(u->meta.load_state == UNIT_STUB);
 202
 203         /* Load a .automount file */
 204         if ((r = unit_load_fragment_and_dropin_optional(u)) < 0)
 205                 return r;
 206
 207         if (u->meta.load_state == UNIT_LOADED) {
 208                 Unit *x;
 209
 210                 if (!a->where)
 211                         if (!(a->where = unit_name_to_path(u->meta.id)))
 212                                 return -ENOMEM;
 213
 214                 path_kill_slashes(a->where);
 215
 216                 if ((r = automount_add_mount_links(a)) < 0)
 217                         return r;
 218
 219                 r = unit_load_related_unit(u, ".mount", &x);
 220                 if (r < 0)
 221                         return r;
 222
 223                 unit_ref_set(&a->mount, x);
 224
 225                 r = unit_add_two_dependencies(u, UNIT_BEFORE, UNIT_TRIGGERS, UNIT_DEREF(a->mount), true);
 226                 if (r < 0)
 227                         return r;
 228
 229                 if (a->meta.default_dependencies)
 230                         if ((r = automount_add_default_dependencies(a)) < 0)
 231                                 return r;
 232         }
 233
 234         return automount_verify(a);
 235 }
 236
 237 static void automount_set_state(Automount *a, AutomountState state) {
 238         AutomountState old_state;
 239         assert(a);
 240
 241         old_state = a->state;
 242         a->state = state;
 243
 244         if (state != AUTOMOUNT_WAITING &&
 245             state != AUTOMOUNT_RUNNING)
 246                 unmount_autofs(a);
 247
 248         if (state != old_state)
 249                 log_debug("%s changed %s -> %s",
 250                           a->meta.id,
 251                           automount_state_to_string(old_state),
 252                           automount_state_to_string(state));
 253
 254         unit_notify(UNIT(a), state_translation_table[old_state], state_translation_table[state], true);
 255 }
 256
 257 static int automount_coldplug(Unit *u) {
 258         Automount *a = AUTOMOUNT(u);
 259         int r;
 260
 261         assert(a);
 262         assert(a->state == AUTOMOUNT_DEAD);
 263
 264         if (a->deserialized_state != a->state) {
 265
 266                 if ((r = open_dev_autofs(u->meta.manager)) < 0)
 267                         return r;
 268
 269                 if (a->deserialized_state == AUTOMOUNT_WAITING ||
 270                     a->deserialized_state == AUTOMOUNT_RUNNING) {
 271
 272                         assert(a->pipe_fd >= 0);
 273
 274                         if ((r = unit_watch_fd(UNIT(a), a->pipe_fd, EPOLLIN, &a->pipe_watch)) < 0)
 275                                 return r;
 276                 }
 277
 278                 automount_set_state(a, a->deserialized_state);
 279         }
 280
 281         return 0;
 282 }
 283
 284 static void automount_dump(Unit *u, FILE *f, const char *prefix) {
 285         Automount *a = AUTOMOUNT(u);
 286
 287         assert(a);
 288
 289         fprintf(f,
 290                 "%sAutomount State: %s\n"
 291                 "%sWhere: %s\n"
 292                 "%sDirectoryMode: %04o\n",
 293                 prefix, automount_state_to_string(a->state),
 294                 prefix, a->where,
 295                 prefix, a->directory_mode);
 296 }
 297
 298 static void automount_enter_dead(Automount *a, bool success) {
 299         assert(a);
 300
 301         if (!success)
 302                 a->failure = true;
 303
 304         automount_set_state(a, a->failure ? AUTOMOUNT_FAILED : AUTOMOUNT_DEAD);
 305 }
 306
 307 static int open_dev_autofs(Manager *m) {
 308         struct autofs_dev_ioctl param;
 309
 310         assert(m);
 311
 312         if (m->dev_autofs_fd >= 0)
 313                 return m->dev_autofs_fd;
 314
 315         label_fix("/dev/autofs", false);
 316
 317         if ((m->dev_autofs_fd = open("/dev/autofs", O_CLOEXEC|O_RDONLY)) < 0) {
 318                 log_error("Failed to open /dev/autofs: %s", strerror(errno));
 319                 return -errno;
 320         }
 321
 322         init_autofs_dev_ioctl(&param);
 323         if (ioctl(m->dev_autofs_fd, AUTOFS_DEV_IOCTL_VERSION, &param) < 0) {
 324                 close_nointr_nofail(m->dev_autofs_fd);
 325                 m->dev_autofs_fd = -1;
 326                 return -errno;
 327         }
 328
 329         log_debug("Autofs kernel version %i.%i", param.ver_major, param.ver_minor);
 330
 331         return m->dev_autofs_fd;
 332 }
 333
 334 static int open_ioctl_fd(int dev_autofs_fd, const char *where, dev_t devid) {
 335         struct autofs_dev_ioctl *param;
 336         size_t l;
 337         int r;
 338
 339         assert(dev_autofs_fd >= 0);
 340         assert(where);
 341
 342         l = sizeof(struct autofs_dev_ioctl) + strlen(where) + 1;
 343
 344         if (!(param = malloc(l)))
 345                 return -ENOMEM;
 346
 347         init_autofs_dev_ioctl(param);
 348         param->size = l;
 349         param->ioctlfd = -1;
 350         param->openmount.devid = devid;
 351         strcpy(param->path, where);
 352
 353         if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_OPENMOUNT, param) < 0) {
 354                 r = -errno;
 355                 goto finish;
 356         }
 357
 358         if (param->ioctlfd < 0) {
 359                 r = -EIO;
 360                 goto finish;
 361         }
 362
 363         fd_cloexec(param->ioctlfd, true);
 364         r = param->ioctlfd;
 365
 366 finish:
 367         free(param);
 368         return r;
 369 }
 370
 371 static int autofs_protocol(int dev_autofs_fd, int ioctl_fd) {
 372         uint32_t major, minor;
 373         struct autofs_dev_ioctl param;
 374
 375         assert(dev_autofs_fd >= 0);
 376         assert(ioctl_fd >= 0);
 377
 378         init_autofs_dev_ioctl(&param);
 379         param.ioctlfd = ioctl_fd;
 380
 381         if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_PROTOVER, &param) < 0)
 382                 return -errno;
 383
 384         major = param.protover.version;
 385
 386         init_autofs_dev_ioctl(&param);
 387         param.ioctlfd = ioctl_fd;
 388
 389         if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_PROTOSUBVER, &param) < 0)
 390                 return -errno;
 391
 392         minor = param.protosubver.sub_version;
 393
 394         log_debug("Autofs protocol version %i.%i", major, minor);
 395         return 0;
 396 }
 397
 398 static int autofs_set_timeout(int dev_autofs_fd, int ioctl_fd, time_t sec) {
 399         struct autofs_dev_ioctl param;
 400
 401         assert(dev_autofs_fd >= 0);
 402         assert(ioctl_fd >= 0);
 403
 404         init_autofs_dev_ioctl(&param);
 405         param.ioctlfd = ioctl_fd;
 406         param.timeout.timeout = sec;
 407
 408         if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_TIMEOUT, &param) < 0)
 409                 return -errno;
 410
 411         return 0;
 412 }
 413
 414 static int autofs_send_ready(int dev_autofs_fd, int ioctl_fd, uint32_t token, int status) {
 415         struct autofs_dev_ioctl param;
 416
 417         assert(dev_autofs_fd >= 0);
 418         assert(ioctl_fd >= 0);
 419
 420         init_autofs_dev_ioctl(&param);
 421         param.ioctlfd = ioctl_fd;
 422
 423         if (status) {
 424                 param.fail.token = token;
 425                 param.fail.status = status;
 426         } else
 427                 param.ready.token = token;
 428
 429         if (ioctl(dev_autofs_fd, status ? AUTOFS_DEV_IOCTL_FAIL : AUTOFS_DEV_IOCTL_READY, &param) < 0)
 430                 return -errno;
 431
 432         return 0;
 433 }
 434
 435 int automount_send_ready(Automount *a, int status) {
 436         int ioctl_fd, r;
 437         unsigned token;
 438
 439         assert(a);
 440         assert(status <= 0);
 441
 442         if (set_isempty(a->tokens))
 443                 return 0;
 444
 445         if ((ioctl_fd = open_ioctl_fd(a->meta.manager->dev_autofs_fd, a->where, a->dev_id)) < 0) {
 446                 r = ioctl_fd;
 447                 goto fail;
 448         }
 449
 450         if (status)
 451                 log_debug("Sending failure: %s", strerror(-status));
 452         else
 453                 log_debug("Sending success.");
 454
 455         r = 0;
 456
 457         /* Autofs thankfully does not hand out 0 as a token */
 458         while ((token = PTR_TO_UINT(set_steal_first(a->tokens)))) {
 459                 int k;
 460
 461                 /* Autofs fun fact II:
 462                  *
 463                  * if you pass a positive status code here, the kernel will
 464                  * freeze! Yay! */
 465
 466                 if ((k = autofs_send_ready(a->meta.manager->dev_autofs_fd,
 467                                            ioctl_fd,
 468                                            token,
 469                                            status)) < 0)
 470                         r = k;
 471         }
 472
 473 fail:
 474         if (ioctl_fd >= 0)
 475                 close_nointr_nofail(ioctl_fd);
 476
 477         return r;
 478 }
 479
 480 static void automount_enter_waiting(Automount *a) {
 481         int p[2] = { -1, -1 };
 482         char name[32], options[128];
 483         bool mounted = false;
 484         int r, ioctl_fd = -1, dev_autofs_fd;
 485         struct stat st;
 486
 487         assert(a);
 488         assert(a->pipe_fd < 0);
 489         assert(a->where);
 490
 491         if (a->tokens)
 492                 set_clear(a->tokens);
 493
 494         if ((dev_autofs_fd = open_dev_autofs(a->meta.manager)) < 0) {
 495                 r = dev_autofs_fd;
 496                 goto fail;
 497         }
 498
 499         /* We knowingly ignore the results of this call */
 500         mkdir_p(a->where, 0555);
 501
 502         if (pipe2(p, O_NONBLOCK|O_CLOEXEC) < 0) {
 503                 r = -errno;
 504                 goto fail;
 505         }
 506
 507         snprintf(options, sizeof(options), "fd=%i,pgrp=%u,minproto=5,maxproto=5,direct", p[1], (unsigned) getpgrp());
 508         char_array_0(options);
 509
 510         snprintf(name, sizeof(name), "systemd-%u", (unsigned) getpid());
 511         char_array_0(name);
 512
 513         if (mount(name, a->where, "autofs", 0, options) < 0) {
 514                 r = -errno;
 515                 goto fail;
 516         }
 517
 518         mounted = true;
 519
 520         close_nointr_nofail(p[1]);
 521         p[1] = -1;
 522
 523         if (stat(a->where, &st) < 0) {
 524                 r = -errno;
 525                 goto fail;
 526         }
 527
 528         if ((ioctl_fd = open_ioctl_fd(dev_autofs_fd, a->where, st.st_dev)) < 0) {
 529                 r = ioctl_fd;
 530                 goto fail;
 531         }
 532
 533         if ((r = autofs_protocol(dev_autofs_fd, ioctl_fd)) < 0)
 534                 goto fail;
 535
 536         if ((r = autofs_set_timeout(dev_autofs_fd, ioctl_fd, 300)) < 0)
 537                 goto fail;
 538
 539         /* Autofs fun fact:
 540          *
 541          * Unless we close the ioctl fd here, for some weird reason
 542          * the direct mount will not receive events from the
 543          * kernel. */
 544
 545         close_nointr_nofail(ioctl_fd);
 546         ioctl_fd = -1;
 547
 548         if ((r = unit_watch_fd(UNIT(a), p[0], EPOLLIN, &a->pipe_watch)) < 0)
 549                 goto fail;
 550
 551         a->pipe_fd = p[0];
 552         a->dev_id = st.st_dev;
 553
 554         automount_set_state(a, AUTOMOUNT_WAITING);
 555
 556         return;
 557
 558 fail:
 559         assert_se(close_pipe(p) == 0);
 560
 561         if (ioctl_fd >= 0)
 562                 close_nointr_nofail(ioctl_fd);
 563
 564         if (mounted)
 565                 repeat_unmout(a->where);
 566
 567         log_error("Failed to initialize automounter: %s", strerror(-r));
 568         automount_enter_dead(a, false);
 569 }
 570
 571 static void automount_enter_runnning(Automount *a) {
 572         int r;
 573         struct stat st;
 574         DBusError error;
 575
 576         assert(a);
 577         assert(UNIT_DEREF(a->mount));
 578
 579         dbus_error_init(&error);
 580
 581         /* We don't take mount requests anymore if we are supposed to
 582          * shut down anyway */
 583         if (unit_pending_inactive(UNIT(a))) {
 584                 log_debug("Suppressing automount request on %s since unit stop is scheduled.", a->meta.id);
 585                 automount_send_ready(a, -EHOSTDOWN);
 586                 return;
 587         }
 588
 589         mkdir_p(a->where, a->directory_mode);
 590
 591         /* Before we do anything, let's see if somebody is playing games with us? */
 592         if (lstat(a->where, &st) < 0) {
 593                 log_warning("%s failed to stat automount point: %m", a->meta.id);
 594                 goto fail;
 595         }
 596
 597         if (!S_ISDIR(st.st_mode) || st.st_dev != a->dev_id)
 598                 log_info("%s's automount point already active?", a->meta.id);
 599         else if ((r = manager_add_job(a->meta.manager, JOB_START, UNIT_DEREF(a->mount), JOB_REPLACE, true, &error, NULL)) < 0) {
 600                 log_warning("%s failed to queue mount startup job: %s", a->meta.id, bus_error(&error, r));
 601                 goto fail;
 602         }
 603
 604         automount_set_state(a, AUTOMOUNT_RUNNING);
 605         return;
 606
 607 fail:
 608         automount_enter_dead(a, false);
 609         dbus_error_free(&error);
 610 }
 611
 612 static int automount_start(Unit *u) {
 613         Automount *a = AUTOMOUNT(u);
 614
 615         assert(a);
 616
 617         assert(a->state == AUTOMOUNT_DEAD || a->state == AUTOMOUNT_FAILED);
 618
 619         if (path_is_mount_point(a->where, false)) {
 620                 log_error("Path %s is already a mount point, refusing start for %s", a->where, u->meta.id);
 621                 return -EEXIST;
 622         }
 623
 624         if (UNIT_DEREF(a->mount)->meta.load_state != UNIT_LOADED)
 625                 return -ENOENT;
 626
 627         a->failure = false;
 628         automount_enter_waiting(a);
 629         return 0;
 630 }
 631
 632 static int automount_stop(Unit *u) {
 633         Automount *a = AUTOMOUNT(u);
 634
 635         assert(a);
 636
 637         assert(a->state == AUTOMOUNT_WAITING || a->state == AUTOMOUNT_RUNNING);
 638
 639         automount_enter_dead(a, true);
 640         return 0;
 641 }
 642
 643 static int automount_serialize(Unit *u, FILE *f, FDSet *fds) {
 644         Automount *a = AUTOMOUNT(u);
 645         void *p;
 646         Iterator i;
 647
 648         assert(a);
 649         assert(f);
 650         assert(fds);
 651
 652         unit_serialize_item(u, f, "state", automount_state_to_string(a->state));
 653         unit_serialize_item(u, f, "failure", yes_no(a->failure));
 654         unit_serialize_item_format(u, f, "dev-id", "%u", (unsigned) a->dev_id);
 655
 656         SET_FOREACH(p, a->tokens, i)
 657                 unit_serialize_item_format(u, f, "token", "%u", PTR_TO_UINT(p));
 658
 659         if (a->pipe_fd >= 0) {
 660                 int copy;
 661
 662                 if ((copy = fdset_put_dup(fds, a->pipe_fd)) < 0)
 663                         return copy;
 664
 665                 unit_serialize_item_format(u, f, "pipe-fd", "%i", copy);
 666         }
 667
 668         return 0;
 669 }
 670
 671 static int automount_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) {
 672         Automount *a = AUTOMOUNT(u);
 673         int r;
 674
 675         assert(a);
 676         assert(fds);
 677
 678         if (streq(key, "state")) {
 679                 AutomountState state;
 680
 681                 if ((state = automount_state_from_string(value)) < 0)
 682                         log_debug("Failed to parse state value %s", value);
 683                 else
 684                         a->deserialized_state = state;
 685         } else if (streq(key, "failure")) {
 686                 int b;
 687
 688                 if ((b = parse_boolean(value)) < 0)
 689                         log_debug("Failed to parse failure value %s", value);
 690                 else
 691                         a->failure = b || a->failure;
 692         } else if (streq(key, "dev-id")) {
 693                 unsigned d;
 694
 695                 if (safe_atou(value, &d) < 0)
 696                         log_debug("Failed to parse dev-id value %s", value);
 697                 else
 698                         a->dev_id = (unsigned) d;
 699         } else if (streq(key, "token")) {
 700                 unsigned token;
 701
 702                 if (safe_atou(value, &token) < 0)
 703                         log_debug("Failed to parse token value %s", value);
 704                 else {
 705                         if (!a->tokens)
 706                                 if (!(a->tokens = set_new(trivial_hash_func, trivial_compare_func)))
 707                                         return -ENOMEM;
 708
 709                         if ((r = set_put(a->tokens, UINT_TO_PTR(token))) < 0)
 710                                 return r;
 711                 }
 712         } else if (streq(key, "pipe-fd")) {
 713                 int fd;
 714
 715                 if (safe_atoi(value, &fd) < 0 || fd < 0 || !fdset_contains(fds, fd))
 716                         log_debug("Failed to parse pipe-fd value %s", value);
 717                 else {
 718                         if (a->pipe_fd >= 0)
 719                                 close_nointr_nofail(a->pipe_fd);
 720
 721                         a->pipe_fd = fdset_remove(fds, fd);
 722                 }
 723         } else
 724                 log_debug("Unknown serialization key '%s'", key);
 725
 726         return 0;
 727 }
 728
 729 static UnitActiveState automount_active_state(Unit *u) {
 730         assert(u);
 731
 732         return state_translation_table[AUTOMOUNT(u)->state];
 733 }
 734
 735 static const char *automount_sub_state_to_string(Unit *u) {
 736         assert(u);
 737
 738         return automount_state_to_string(AUTOMOUNT(u)->state);
 739 }
 740
 741 static bool automount_check_gc(Unit *u) {
 742         Automount *a = AUTOMOUNT(u);
 743
 744         assert(a);
 745
 746         if (!UNIT_DEREF(a->mount))
 747                 return false;
 748
 749         return UNIT_VTABLE(UNIT_DEREF(a->mount))->check_gc(UNIT_DEREF(a->mount));
 750 }
 751
 752 static void automount_fd_event(Unit *u, int fd, uint32_t events, Watch *w) {
 753         Automount *a = AUTOMOUNT(u);
 754         union autofs_v5_packet_union packet;
 755         ssize_t l;
 756         int r;
 757
 758         assert(a);
 759         assert(fd == a->pipe_fd);
 760
 761         if (events != EPOLLIN) {
 762                 log_error("Got invalid poll event on pipe.");
 763                 goto fail;
 764         }
 765
 766         if ((l = loop_read(a->pipe_fd, &packet, sizeof(packet), true)) != sizeof(packet)) {
 767                 log_error("Invalid read from pipe: %s", l < 0 ? strerror(-l) : "short read");
 768                 goto fail;
 769         }
 770
 771         switch (packet.hdr.type) {
 772
 773         case autofs_ptype_missing_direct:
 774
 775                 if (packet.v5_packet.pid > 0) {
 776                         char *p = NULL;
 777
 778                         get_process_comm(packet.v5_packet.pid, &p);
 779                         log_debug("Got direct mount request for %s, triggered by %lu (%s)", packet.v5_packet.name, (unsigned long) packet.v5_packet.pid, strna(p));
 780                         free(p);
 781
 782                 } else
 783                         log_debug("Got direct mount request for %s", packet.v5_packet.name);
 784
 785                 if (!a->tokens)
 786                         if (!(a->tokens = set_new(trivial_hash_func, trivial_compare_func))) {
 787                                 log_error("Failed to allocate token set.");
 788                                 goto fail;
 789                         }
 790
 791                 if ((r = set_put(a->tokens, UINT_TO_PTR(packet.v5_packet.wait_queue_token))) < 0) {
 792                         log_error("Failed to remember token: %s", strerror(-r));
 793                         goto fail;
 794                 }
 795
 796                 automount_enter_runnning(a);
 797                 break;
 798
 799         default:
 800                 log_error("Received unknown automount request %i", packet.hdr.type);
 801                 break;
 802         }
 803
 804         return;
 805
 806 fail:
 807         automount_enter_dead(a, false);
 808 }
 809
 810 static void automount_shutdown(Manager *m) {
 811         assert(m);
 812
 813         if (m->dev_autofs_fd >= 0)
 814                 close_nointr_nofail(m->dev_autofs_fd);
 815 }
 816
 817 static void automount_reset_failed(Unit *u) {
 818         Automount *a = AUTOMOUNT(u);
 819
 820         assert(a);
 821
 822         if (a->state == AUTOMOUNT_FAILED)
 823                 automount_set_state(a, AUTOMOUNT_DEAD);
 824
 825         a->failure = false;
 826 }
 827
 828 static const char* const automount_state_table[_AUTOMOUNT_STATE_MAX] = {
 829         [AUTOMOUNT_DEAD] = "dead",
 830         [AUTOMOUNT_WAITING] = "waiting",
 831         [AUTOMOUNT_RUNNING] = "running",
 832         [AUTOMOUNT_FAILED] = "failed"
 833 };
 834
 835 DEFINE_STRING_TABLE_LOOKUP(automount_state, AutomountState);
 836
 837 const UnitVTable automount_vtable = {
 838         .suffix = ".automount",
 839         .object_size = sizeof(Automount),
 840         .sections =
 841                 "Unit\0"
 842                 "Automount\0"
 843                 "Install\0",
 844
 845         .no_alias = true,
 846         .no_instances = true,
 847
 848         .init = automount_init,
 849         .load = automount_load,
 850         .done = automount_done,
 851
 852         .coldplug = automount_coldplug,
 853
 854         .dump = automount_dump,
 855
 856         .start = automount_start,
 857         .stop = automount_stop,
 858
 859         .serialize = automount_serialize,
 860         .deserialize_item = automount_deserialize_item,
 861
 862         .active_state = automount_active_state,
 863         .sub_state_to_string = automount_sub_state_to_string,
 864
 865         .check_gc = automount_check_gc,
 866
 867         .fd_event = automount_fd_event,
 868
 869         .reset_failed = automount_reset_failed,
 870
 871         .bus_interface = "org.freedesktop.systemd1.Automount",
 872         .bus_message_handler = bus_automount_message_handler,
 873
 874         .shutdown = automount_shutdown
 875 };